903 files changed, 48589 insertions, 42444 deletions

diff --git a/.gitignore b/.gitignore
index 7bc051278c..011463cbc9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -29,6 +29,7 @@ autom4te.cache
 # Do not use too creative wildcards.
 # Those might ignore files that should not be ignored.
 
+armv7l-unknown-linux-gnueabihf
 i686-pc-linux-gnu
 x86_64-unknown-linux-gnu
 i386-apple-darwin[0-9]*.[0-9]*.[0-9]*
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index ca9674d103..c89301d0eb 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -1,5 +1,38 @@
 # Contributing to Erlang/OTP
 
+## License
+
+By making a contribution to this project, I certify that:
+(a) The contribution was created in whole or in part by me and I
+    have the right to submit it under the open source license
+    indicated in the file; or
+
+(b) The contribution is based upon previous work that, to the 
+    best of my knowledge, is covered under an appropriate open 
+    source license and I have the right under that license to   
+    submit that work with modifications, whether created in whole
+    or in part by me, under the same open source license (unless
+    I am permitted to submit under a different license), as 
+    Indicated in the file; or
+
+(c) The contribution was provided directly to me by some other
+    person who certified (a), (b) or (c) and I have not modified
+    it.
+
+(d) I understand and agree that this project and the contribution
+    are public and that a record of the contribution (including 
+    all personal information I submit with it, including my
+    sign-off) is maintained indefinitely and may be redistributed
+    consistent with this project or the open source license(s)
+    involved.
+
+Erlang/otp is licensed under the
+Apache License 2.0
+
+As stated in: LICENSE.txt 
+
+http://developercertificate.org/
+
 ## Reporting a bug
 
 Report bugs at https://bugs.erlang.org. See [Bug reports](https://github.com/erlang/otp/wiki/Bug-reports)
diff --git a/HOWTO/DTRACE.md b/HOWTO/DTRACE.md
index 90f4addefd..0c08b6cc3d 100644
--- a/HOWTO/DTRACE.md
+++ b/HOWTO/DTRACE.md
@@ -46,346 +46,11 @@ although it's considered experimental. The main development of the dtrace code
 still happens outside of Ericsson, but there is no need to fetch a patched 
 version of the OTP source to get the basic funtionality.
 
-Implementation summary
-----------------------
+DTrace probe specifications
+---------------------------
 
-So far, most effort has been focused on the `efile_drv.c` code,
-which implements most file I/O on behalf of the Erlang virtual
-machine.  This driver also presents a big challenge: its use of an I/O
-worker pool (enabled by using the `erl +A 8` flag, for example) makes
-it much more difficult to trace I/O activity because each of the
-following may be executed in a different Pthread:
-
-* I/O initiation (Erlang code)
-* I/O proxy process handling, e.g. read/write when file is not opened
-  in `raw` mode, operations executed by the code & file server processes.
-  (Erlang code)
-* `efile_drv` command setup (C code)
-* `efile_drv` command execution (C code)
-* `efile_drv` status return (C code)
-
-Example output from `lib/runtime_tools/examples/efile_drv.d` while executing
-`file:rename("old-name", "new-name")`:
-
-    efile_drv enter tag={3,84} user tag some-user-tag | RENAME (12) | args: old-name new-name ,\
-          0 0 (port #Port<0.59>)
-    async I/O worker tag={3,83} | RENAME (12) | efile_drv-int_entry
-    async I/O worker tag={3,83} | RENAME (12) | efile_drv-int_return
-    efile_drv return tag={3,83} user tag  | RENAME (12) | errno 2
-
-... where the following key can help decipher the output:
-
-* `{3,83}` is the Erlang scheduler thread number (3) and operation
-  counter number (83) assigned to this I/O operation.  Together,
-  these two numbers form a unique ID for the I/O operation.
-* `12` is the command number for the rename operation.  See the
-  definition for `FILE_RENAME` in the source code file `efile_drv.c`
-  or the `BEGIN` section of the D script `lib/runtime_tools/examples/efile_drv.d`.
-* `old-name` and `new-name` are the two string arguments for the
-  source and destination of the `rename(2)` system call.
-  The two integer arguments are unused; the simple formatting code
-  prints the arguments anyway, 0 and 0.
-* The worker pool code was called on behalf of Erlang port `#Port<0.59>`.
-* The system call failed with a POSIX errno value of 2: `ENOENT`,
-  because the path `old-name` does not exist.
-* The `efile_drv-int_entry` and `efile_drv_int_return` probes are
-  provided in case the user is
-  interested in measuring only the latency of code executed by
-  `efile_drv` asynchronous functions by I/O worker pool threads
-  and the OS system call that they encapsulate.
-
-So, where does the `some-user-tag` string come from?
-
-At the moment, the user tag comes from code like the following:
-
-    dyntrace:put_tag("some-user-tag"),
-    file:rename("old-name", "new-name"),
-
-This method of tagging I/O at the Erlang level is subject to change.
-
-Example DTrace probe specification
-----------------------------------
-
-    /**
-     * Fired when a message is sent from one local process to another.
-     *
-     * NOTE: The 'size' parameter is in machine-dependent words and
-     *       that the actual size of any binary terms in the message
-     *       are not included.
-     *
-     * @param sender the PID (string form) of the sender
-     * @param receiver the PID (string form) of the receiver
-     * @param size the size of the message being delivered (words)
-     * @param token_label for the sender's sequential trace token
-     * @param token_previous count for the sender's sequential trace token
-     * @param token_current count for the sender's sequential trace token
-     */
-    probe message__send(char *sender, char *receiver, uint32_t size,
-                        int token_label, int token_previous, int token_current);
-
-    /**
-     * Fired when a message is sent from a local process to a remote process.
-     *
-     * NOTE: The 'size' parameter is in machine-dependent words and
-     *       that the actual size of any binary terms in the message
-     *       are not included.
-     *
-     * @param sender the PID (string form) of the sender
-     * @param node_name the Erlang node name (string form) of the receiver
-     * @param receiver the PID/name (string form) of the receiver
-     * @param size the size of the message being delivered (words)
-     * @param token_label for the sender's sequential trace token
-     * @param token_previous count for the sender's sequential trace token
-     * @param token_current count for the sender's sequential trace token
-     */
-    probe message__send__remote(char *sender, char *node_name, char *receiver,
-                                uint32_t size,
-                        int token_label, int token_previous, int token_current);
-
-    /**
-     * Fired when a message is queued to a local process.  This probe
-     * will not fire if the sender's pid == receiver's pid.
-     *
-     * NOTE: The 'size' parameter is in machine-dependent words and
-     *       that the actual size of any binary terms in the message
-     *       are not included.
-     *
-     * @param receiver the PID (string form) of the receiver
-     * @param size the size of the message being delivered (words)
-     * @param queue_len length of the queue of the receiving process
-     * @param token_label for the sender's sequential trace token
-     * @param token_previous count for the sender's sequential trace token
-     * @param token_current count for the sender's sequential trace token
-     */
-    probe message__queued(char *receiver, uint32_t size, uint32_t queue_len,
-                        int token_label, int token_previous, int token_current);
-
-    /**
-     * Fired when a message is 'receive'd by a local process and removed
-     * from its mailbox.
-     *
-     * NOTE: The 'size' parameter is in machine-dependent words and
-     *       that the actual size of any binary terms in the message
-     *       are not included.
-     *
-     * @param receiver the PID (string form) of the receiver
-     * @param size the size of the message being delivered (words)
-     * @param queue_len length of the queue of the receiving process
-     * @param token_label for the sender's sequential trace token
-     * @param token_previous count for the sender's sequential trace token
-     * @param token_current count for the sender's sequential trace token
-     */
-    probe message__receive(char *receiver, uint32_t size, uint32_t queue_len,
-                        int token_label, int token_previous, int token_current);
-
-    /* ... */
-
-    /* Async driver pool */
-
-    /**
-     * Show the post-add length of the async driver thread pool member's queue.
-     *
-     * NOTE: The port name is not available: additional lock(s) must
-     *       be acquired in order to get the port name safely in an SMP
-     *       environment.  The same is true for the aio__pool_get probe.
-     *
-     * @param port the Port (string form)
-     * @param new queue length
-     */
-    probe aio_pool__add(char *, int);
-
-    /**
-     * Show the post-get length of the async driver thread pool member's queue.
-     *
-     * @param port the Port (string form)
-     * @param new queue length
-     */
-    probe aio_pool__get(char *, int);
-
-    /* Probes for efile_drv.c */
-
-    /**
-     * Entry into the efile_drv.c file I/O driver
-     *
-     * For a list of command numbers used by this driver, see the section
-     * "Guide to probe arguments" in ../../../README.md.  That section
-     * also contains explanation of the various integer and string
-     * arguments that may be present when any particular probe fires.
-     *
-     * TODO: Adding the port string, args[10], is a pain.  Making that
-     *       port string available to all the other efile_drv.c probes
-     *       will be more pain.  Is the pain worth it?  If yes, then
-     *       add them everywhere else and grit our teeth.  If no, then
-     *       rip it out.
-     *
-     * @param thread-id number of the scheduler Pthread                   arg0
-     * @param tag number: {thread-id, tag} uniquely names a driver operation
-     * @param user-tag string                                             arg2
-     * @param command number                                              arg3
-     * @param string argument 1                                           arg4
-     * @param string argument 2                                           arg5
-     * @param integer argument 1                                          arg6
-     * @param integer argument 2                                          arg7
-     * @param integer argument 3                                          arg8
-     * @param integer argument 4                                          arg9
-     * @param port the port ID of the busy port                       args[10]
-     */
-    probe efile_drv__entry(int, int, char *, int, char *, char *,
-                           int64_t, int64_t, int64_t, int64_t, char *);
-
-    /**
-     * Entry into the driver's internal work function.  Computation here
-     * is performed by a async worker pool Pthread.
-     *
-     * @param thread-id number
-     * @param tag number
-     * @param command number
-     */
-    probe efile_drv__int_entry(int, int, int);
-
-    /**
-     * Return from the driver's internal work function.
-     *
-     * @param thread-id number
-     * @param tag number
-     * @param command number
-     */
-    probe efile_drv__int_return(int, int, int);
-
-    /**
-     * Return from the efile_drv.c file I/O driver
-     *
-     * @param thread-id number                                            arg0
-     * @param tag number                                                  arg1
-     * @param user-tag string                                             arg2
-     * @param command number                                              arg3
-     * @param Success? 1 is success, 0 is failure                         arg4
-     * @param If failure, the errno of the error.                         arg5
-     */
-    probe efile_drv__return(int, int, char *, int, int, int);
-
-Guide to efile_drv.c probe arguments
-------------------------------------
-
-    /* Driver op code: used by efile_drv-entry      arg3 */
-    /*                 used by efile_drv-int_entry  arg3 */
-    /*                 used by efile_drv-int_return arg3 */
-    /*                 used by efile_drv-return     arg3 */
-
-    #define FILE_OPEN            1                 (probe arg3)
-            probe arg6 = C driver dt_i1 = flags;
-            probe arg4 = C driver dt_s1 = path;
-
-    #define FILE_READ            2                 (probe arg3)
-            probe arg6 = C driver dt_i1 = fd;
-            probe arg7 = C driver dt_i2 = flags;
-            probe arg8 = C driver dt_i3 = size;
-
-    #define FILE_LSEEK           3                 (probe arg3)
-            probe arg6 = C driver dt_i1 = fd;
-            probe arg7 = C driver dt_i2 = offset;
-            probe arg8 = C driver dt_i3 = origin;
-
-    #define FILE_WRITE           4                 (probe arg3)
-            probe arg6 = C driver dt_i1 = fd;
-            probe arg7 = C driver dt_i2 = flags;
-            probe arg8 = C driver dt_i3 = size;
-
-    #define FILE_FSTAT           5                 (probe arg3)
-            probe arg6 = C driver dt_i1 = fd;
-
-    #define FILE_PWD             6                 (probe arg3)
-            none
-
-    #define FILE_READDIR         7                 (probe arg3)
-            probe arg4 = C driver dt_s1 = path;
-
-    #define FILE_CHDIR           8                 (probe arg3)
-            probe arg4 = C driver dt_s1 = path;
-
-    #define FILE_FSYNC           9                 (probe arg3)
-                probe arg6 = C driver dt_i1 = fd;
-
-    #define FILE_MKDIR          10                 (probe arg3)
-            probe arg4 = C driver dt_s1 = path;
-
-    #define FILE_DELETE         11                 (probe arg3)
-            probe arg4 = C driver dt_s1 = path;
-
-    #define FILE_RENAME         12                 (probe arg3)
-            probe arg4 = C driver dt_s1 = old_name;
-            probe arg5 = C driver dt_s2 = new_name;
-
-    #define FILE_RMDIR          13                 (probe arg3)
-            probe arg4 = C driver dt_s1 = path;
-
-    #define FILE_TRUNCATE       14                 (probe arg3)
-            probe arg6 = C driver dt_i1 = fd;
-            probe arg7 = C driver dt_i2 = flags;
-
-    #define FILE_READ_FILE      15                 (probe arg3)
-            probe arg4 = C driver dt_s1 = path;
-
-    #define FILE_WRITE_INFO     16                 (probe arg3)
-            probe arg6 = C driver dt_i1 = mode;
-            probe arg7 = C driver dt_i2 = uid;
-            probe arg8 = C driver dt_i3 = gid;
-
-    #define FILE_LSTAT          19                 (probe arg3)
-            probe arg4 = C driver dt_s1 = path;
-
-    #define FILE_READLINK       20                 (probe arg3)
-            probe arg4 = C driver dt_s1 = path;
-
-    #define FILE_LINK           21                 (probe arg3)
-            probe arg4 = C driver dt_s1 = existing_path;
-            probe arg5 = C driver dt_s2 = new_path;
-
-    #define FILE_SYMLINK        22                 (probe arg3)
-            probe arg4 = C driver dt_s1 = existing_path;
-            probe arg5 = C driver dt_s2 = new_path;
-
-    #define FILE_CLOSE          23                 (probe arg3)
-            probe arg6 = C driver dt_i1 = fd;
-            probe arg7 = C driver dt_i2 = flags;
-
-    #define FILE_PWRITEV        24                 (probe arg3)
-            probe arg6 = C driver dt_i1 = fd;
-            probe arg7 = C driver dt_i2 = flags;
-            probe arg8 = C driver dt_i3 = size;
-
-    #define FILE_PREADV         25                 (probe arg3)
-            probe arg6 = C driver dt_i1 = fd;
-            probe arg7 = C driver dt_i2 = flags;
-            probe arg8 = C driver dt_i3 = size;
-
-    #define FILE_SETOPT         26                 (probe arg3)
-            probe arg6 = C driver dt_i1 = opt_name;
-            probe arg7 = C driver dt_i2 = opt_specific_value;
-
-    #define FILE_IPREAD         27                 (probe arg3)
-            probe arg6 = C driver dt_i1 = fd;
-            probe arg7 = C driver dt_i2 = flags;
-            probe arg8 = C driver dt_i3 = offsets[0];
-            probe arg9 = C driver dt_i4 = size;
-
-    #define FILE_ALTNAME        28                 (probe arg3)
-            probe arg4 = C driver dt_s1 = path;
-
-    #define FILE_READ_LINE      29                 (probe arg3)
-            probe arg6 = C driver dt_i1 = fd;
-            probe arg7 = C driver dt_i2 = flags;
-            probe arg8 = C driver dt_i3 = read_offset;
-            probe arg9 = C driver dt_i4 = read_ahead;
-
-    #define FILE_FDATASYNC      30                 (probe arg3)
-            probe arg6 = C driver dt_i1 = fd;
-
-    #define FILE_FADVISE        31                 (probe arg3)
-            probe arg6 = C driver dt_i1 = fd;
-            probe arg7 = C driver dt_i2 = offset;
-            probe arg8 = C driver dt_i3 = length;
-            probe arg9 = C driver dt_i4 = advise_type;
+Probe specifications can be found in `erts/emulator/beam/erlang_dtrace.d`, and
+a few example scripts can be found under `lib/runtime_tools/examples/`.
 
    [1]: http://www.erlang.org/euc/08/
    [$ERL_TOP/HOWTO/SYSTEMTAP.md]: SYSTEMTAP.md
diff --git a/HOWTO/INSTALL.md b/HOWTO/INSTALL.md
index 53f2dd26e2..f7de69166a 100644
--- a/HOWTO/INSTALL.md
+++ b/HOWTO/INSTALL.md
@@ -340,12 +340,6 @@ use the `--prefix` argument like this: `./configure --prefix=<Dir>`.
 Some of the available `configure` options are:
 
 *   `--prefix=PATH` - Specify installation prefix.
-*   `--enable-plain-emulator` - Build a threaded emulator that only
-    uses one scheduler. This emulator type is deprecated and will be
-    removed in a future release.
-*   `--disable-threads` - Build a non-threaded emulator. This emulator type
-    is deprecated and will be
-    removed in a future release.
 *   `--{enable,disable}-kernel-poll` - Kernel poll support (enabled by
     default if possible)
 *   `--{enable,disable}-hipe` - HiPE support (enabled by default on supported
@@ -423,11 +417,6 @@ Some of the available `configure` options are:
     and scalability compared to the default clock sources chosen.
 *   `--disable-saved-compile-time` - Disable saving of compile date and time
     in the emulator binary.
-*   `--enable-dirty-schedulers` - Enable the **experimental** dirty schedulers
-    functionality. Note that the dirty schedulers functionality is experimental,
-    and **not supported**. This functionality **will** be subject to backward
-    incompatible changes. Note that you should **not** enable the dirty scheduler
-    functionality on production systems. It is only provided for testing.
 
 If you or your system has special requirements please read the `Makefile` for
 additional configuration information.
@@ -586,16 +575,12 @@ as before, but the build process will take a much longer time.
 
 After completing all the normal building steps described above a debug
 enabled runtime system can be built. To do this you have to change
-directory to `$ERL_TOP/erts/emulator`.
+directory to `$ERL_TOP/erts/emulator` and execute:
 
-In this directory execute:
+    $ (cd $ERL_TOP/erts/emulator && make debug)
 
-    $ make debug FLAVOR=$FLAVOR
-
-where `$FLAVOR` is either `plain` or `smp`. The flavor options will
-produce a beam.debug and beam.smp.debug executable respectively. The
-files are installed along side with the normal (opt) versions `beam.smp`
-and `beam`.
+This will produce a  beam.smp.debug executable. The
+file are installed along side with the normal (opt) version `beam.smp`.
 
 To start the debug enabled runtime system execute:
 
@@ -609,7 +594,7 @@ using appropriate configure options.
 There are other types of runtime systems that can be built as well
 using the similar steps just described.
 
-    $ make $TYPE FLAVOR=$FLAVOR
+    $ (cd $ERL_TOP/erts/emulator && make $TYPE)
 
 where `$TYPE` is `opt`, `gcov`, `gprof`, `debug`, `valgrind`, or `lcnt`.
 These different beam types are useful for debugging and profiling
diff --git a/Makefile.in b/Makefile.in
index 3dce72ba78..3289f1d86b 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -316,6 +316,7 @@ endif
 # The steps to build a working system are:
 #   * build an emulator
 #   * setup the erl and erlc program in bootstrap/bin
+#   * optionally run pgo and build optimized emulator
 #   * build additional compilers and copy them into bootstrap/lib
 #   * use the bootstrap erl and erlc to build all the libs
 #
@@ -396,7 +397,7 @@ else
 endif
 	cd $(ERL_TOP)/erts && \
 	  ERL_TOP=$(ERL_TOP) PATH=$(INST_PATH_PREFIX)"$${PATH}" \
-	    $(MAKE) BUILD_ALL=1 TESTROOT="$(RELEASE_ROOT)" release
+	    $(MAKE) BUILD_ALL=1 PROFILE=$(PROFILE) TESTROOT="$(RELEASE_ROOT)" release
 ifeq ($(RELEASE_ROOT),)
 	$(INSTALL_DATA) "$(ERL_TOP)/OTP_VERSION" "$(OTP_DEFAULT_RELEASE_PATH)/releases/@OTP_REL@"
 else
@@ -450,10 +451,24 @@ BOOT_BINDIR=$(BOOTSTRAP_ROOT)/bootstrap/erts/bin
 BEAM_EVM=$(ERL_TOP)/bin/$(TARGET)/beam_evm
 BOOTSTRAP_COMPILER  =  $(BOOTSTRAP_TOP)/primary_compiler
 
+# otp.mk is only used to figure out if we are doing PGO or not
+include $(ERL_TOP)/make/$(TARGET)/otp.mk
+
 .PHONY: emulator libs kernel stdlib compiler hipe syntax_tools preloaded
 
-emulator:
-	$(make_verbose)cd erts && ERL_TOP=$(ERL_TOP) $(MAKE) NO_START_SCRIPTS=true $(TYPE) FLAVOR=$(FLAVOR)
+ifeq ($(USE_PGO), true)
+PROFILE=use
+PROFILE_EMU_DEPS=emulator_profile_generate bootstrap_setup
+emulator_profile_generate:
+	$(make_verbose)cd erts && ERL_TOP=$(ERL_TOP) $(MAKE) NO_START_SCRIPTS=true $(TYPE) FLAVOR=$(FLAVOR) PROFILE=generate
+else
+PROFILE=
+PROFILE_EMU_DEPS=
+endif
+
+emulator: $(PROFILE_EMU_DEPS)
+	$(make_verbose)cd erts && ERL_TOP=$(ERL_TOP) PATH=$(BOOT_PREFIX)"$${PATH}" \
+	  $(MAKE) NO_START_SCRIPTS=true $(TYPE) FLAVOR=$(FLAVOR) PROFILE=$(PROFILE)
 
 libs:
 ifeq ($(OTP_SMALL_BUILD),true)
@@ -1019,7 +1034,7 @@ install-docs:
 install.emulator:
 	cd erts && \
 	  ERL_TOP=$(ERL_TOP) PATH=$(INST_PATH_PREFIX)"$${PATH}" \
-	  $(MAKE) TESTROOT="$(ERLANG_LIBDIR)" release
+	  $(MAKE) PROFILE=$(PROFILE) TESTROOT="$(ERLANG_LIBDIR)" release
 
 install.libs:
 ifeq ($(OTP_SMALL_BUILD),true)
diff --git a/OTP_VERSION b/OTP_VERSION
index 5e83434edb..06d4ac2bfd 100644
--- a/OTP_VERSION
+++ b/OTP_VERSION
@@ -1 +1 @@
-20.2.2
+21.0-rc0
diff --git a/bootstrap/bin/no_dot_erlang.boot b/bootstrap/bin/no_dot_erlang.boot
new file mode 100644
index 0000000000..2b909efb58
--- /dev/null
+++ b/bootstrap/bin/no_dot_erlang.boot
diff --git a/bootstrap/bin/start.boot b/bootstrap/bin/start.boot
index c5fa075a18..2b909efb58 100644
--- a/bootstrap/bin/start.boot
+++ b/bootstrap/bin/start.boot
diff --git a/bootstrap/bin/start_clean.boot b/bootstrap/bin/start_clean.boot
index c5fa075a18..2b909efb58 100644
--- a/bootstrap/bin/start_clean.boot
+++ b/bootstrap/bin/start_clean.boot
diff --git a/bootstrap/lib/compiler/ebin/beam_a.beam b/bootstrap/lib/compiler/ebin/beam_a.beam
index 1c8753b2d1..47376e1964 100644
--- a/bootstrap/lib/compiler/ebin/beam_a.beam
+++ b/bootstrap/lib/compiler/ebin/beam_a.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_asm.beam b/bootstrap/lib/compiler/ebin/beam_asm.beam
index 936e6886a6..7ce46af61c 100644
--- a/bootstrap/lib/compiler/ebin/beam_asm.beam
+++ b/bootstrap/lib/compiler/ebin/beam_asm.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_block.beam b/bootstrap/lib/compiler/ebin/beam_block.beam
index 84e6e64efc..98d5ec2e59 100644
--- a/bootstrap/lib/compiler/ebin/beam_block.beam
+++ b/bootstrap/lib/compiler/ebin/beam_block.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_bs.beam b/bootstrap/lib/compiler/ebin/beam_bs.beam
index e9be7763ad..edbc6fd015 100644
--- a/bootstrap/lib/compiler/ebin/beam_bs.beam
+++ b/bootstrap/lib/compiler/ebin/beam_bs.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_bsm.beam b/bootstrap/lib/compiler/ebin/beam_bsm.beam
index 24992e9b90..087e0dcf84 100644
--- a/bootstrap/lib/compiler/ebin/beam_bsm.beam
+++ b/bootstrap/lib/compiler/ebin/beam_bsm.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_clean.beam b/bootstrap/lib/compiler/ebin/beam_clean.beam
index b6c47725c6..c856c87a45 100644
--- a/bootstrap/lib/compiler/ebin/beam_clean.beam
+++ b/bootstrap/lib/compiler/ebin/beam_clean.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_dead.beam b/bootstrap/lib/compiler/ebin/beam_dead.beam
index 088898eea3..bb72855294 100644
--- a/bootstrap/lib/compiler/ebin/beam_dead.beam
+++ b/bootstrap/lib/compiler/ebin/beam_dead.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_dict.beam b/bootstrap/lib/compiler/ebin/beam_dict.beam
index 5b4ba12152..913c0ec1fe 100644
--- a/bootstrap/lib/compiler/ebin/beam_dict.beam
+++ b/bootstrap/lib/compiler/ebin/beam_dict.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_disasm.beam b/bootstrap/lib/compiler/ebin/beam_disasm.beam
index 3b9b0bba18..1e6d90af35 100644
--- a/bootstrap/lib/compiler/ebin/beam_disasm.beam
+++ b/bootstrap/lib/compiler/ebin/beam_disasm.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_except.beam b/bootstrap/lib/compiler/ebin/beam_except.beam
index 8c94b74d8c..b5f059596f 100644
--- a/bootstrap/lib/compiler/ebin/beam_except.beam
+++ b/bootstrap/lib/compiler/ebin/beam_except.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_flatten.beam b/bootstrap/lib/compiler/ebin/beam_flatten.beam
index 50e2ce7ab4..ebd383c76c 100644
--- a/bootstrap/lib/compiler/ebin/beam_flatten.beam
+++ b/bootstrap/lib/compiler/ebin/beam_flatten.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_jump.beam b/bootstrap/lib/compiler/ebin/beam_jump.beam
index 7b66277f10..278f03351c 100644
--- a/bootstrap/lib/compiler/ebin/beam_jump.beam
+++ b/bootstrap/lib/compiler/ebin/beam_jump.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_listing.beam b/bootstrap/lib/compiler/ebin/beam_listing.beam
index 74695349ba..87a8791bc4 100644
--- a/bootstrap/lib/compiler/ebin/beam_listing.beam
+++ b/bootstrap/lib/compiler/ebin/beam_listing.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_opcodes.beam b/bootstrap/lib/compiler/ebin/beam_opcodes.beam
index b8b04bbe8b..04305d7896 100644
--- a/bootstrap/lib/compiler/ebin/beam_opcodes.beam
+++ b/bootstrap/lib/compiler/ebin/beam_opcodes.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_peep.beam b/bootstrap/lib/compiler/ebin/beam_peep.beam
index a26cb84590..5e1235dca5 100644
--- a/bootstrap/lib/compiler/ebin/beam_peep.beam
+++ b/bootstrap/lib/compiler/ebin/beam_peep.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_receive.beam b/bootstrap/lib/compiler/ebin/beam_receive.beam
index 6e864e4837..e19d878513 100644
--- a/bootstrap/lib/compiler/ebin/beam_receive.beam
+++ b/bootstrap/lib/compiler/ebin/beam_receive.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_record.beam b/bootstrap/lib/compiler/ebin/beam_record.beam
index 7b855184fb..542bd13d20 100644
--- a/bootstrap/lib/compiler/ebin/beam_record.beam
+++ b/bootstrap/lib/compiler/ebin/beam_record.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_reorder.beam b/bootstrap/lib/compiler/ebin/beam_reorder.beam
index 4b1c7f6d15..9f1668c97f 100644
--- a/bootstrap/lib/compiler/ebin/beam_reorder.beam
+++ b/bootstrap/lib/compiler/ebin/beam_reorder.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_split.beam b/bootstrap/lib/compiler/ebin/beam_split.beam
index 4202961791..d53a8a8b97 100644
--- a/bootstrap/lib/compiler/ebin/beam_split.beam
+++ b/bootstrap/lib/compiler/ebin/beam_split.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_trim.beam b/bootstrap/lib/compiler/ebin/beam_trim.beam
index 1aa648532b..9025e3ca1a 100644
--- a/bootstrap/lib/compiler/ebin/beam_trim.beam
+++ b/bootstrap/lib/compiler/ebin/beam_trim.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_type.beam b/bootstrap/lib/compiler/ebin/beam_type.beam
index 1a4bdd5c5e..ecebbdef66 100644
--- a/bootstrap/lib/compiler/ebin/beam_type.beam
+++ b/bootstrap/lib/compiler/ebin/beam_type.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_utils.beam b/bootstrap/lib/compiler/ebin/beam_utils.beam
index 5a14b35026..adb835d20a 100644
--- a/bootstrap/lib/compiler/ebin/beam_utils.beam
+++ b/bootstrap/lib/compiler/ebin/beam_utils.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_validator.beam b/bootstrap/lib/compiler/ebin/beam_validator.beam
index c9455c28e7..6597bc7ad6 100644
--- a/bootstrap/lib/compiler/ebin/beam_validator.beam
+++ b/bootstrap/lib/compiler/ebin/beam_validator.beam
diff --git a/bootstrap/lib/compiler/ebin/beam_z.beam b/bootstrap/lib/compiler/ebin/beam_z.beam
index 991226cc18..a95d070cff 100644
--- a/bootstrap/lib/compiler/ebin/beam_z.beam
+++ b/bootstrap/lib/compiler/ebin/beam_z.beam
diff --git a/bootstrap/lib/compiler/ebin/cerl.beam b/bootstrap/lib/compiler/ebin/cerl.beam
index 2af5f13b49..7315ab8100 100644
--- a/bootstrap/lib/compiler/ebin/cerl.beam
+++ b/bootstrap/lib/compiler/ebin/cerl.beam
diff --git a/bootstrap/lib/compiler/ebin/cerl_clauses.beam b/bootstrap/lib/compiler/ebin/cerl_clauses.beam
index 3e7a816876..fe1a83018e 100644
--- a/bootstrap/lib/compiler/ebin/cerl_clauses.beam
+++ b/bootstrap/lib/compiler/ebin/cerl_clauses.beam
diff --git a/bootstrap/lib/compiler/ebin/cerl_inline.beam b/bootstrap/lib/compiler/ebin/cerl_inline.beam
index 61edb6b3df..4036eaf5a6 100644
--- a/bootstrap/lib/compiler/ebin/cerl_inline.beam
+++ b/bootstrap/lib/compiler/ebin/cerl_inline.beam
diff --git a/bootstrap/lib/compiler/ebin/cerl_trees.beam b/bootstrap/lib/compiler/ebin/cerl_trees.beam
index 6d64dd7da0..fc525300df 100644
--- a/bootstrap/lib/compiler/ebin/cerl_trees.beam
+++ b/bootstrap/lib/compiler/ebin/cerl_trees.beam
diff --git a/bootstrap/lib/compiler/ebin/compile.beam b/bootstrap/lib/compiler/ebin/compile.beam
index c50f648238..1cfe725032 100644
--- a/bootstrap/lib/compiler/ebin/compile.beam
+++ b/bootstrap/lib/compiler/ebin/compile.beam
diff --git a/bootstrap/lib/compiler/ebin/compiler.app b/bootstrap/lib/compiler/ebin/compiler.app
index 7de02551fe..01e2c478d4 100644
--- a/bootstrap/lib/compiler/ebin/compiler.app
+++ b/bootstrap/lib/compiler/ebin/compiler.app
@@ -19,7 +19,7 @@
 
 {application, compiler,
  [{description, "ERTS  CXC 138 10"},
-  {vsn, "7.1.1"},
+  {vsn, "7.1.3"},
   {modules, [
 	     beam_a,
 	     beam_asm,
@@ -58,6 +58,7 @@
 	     core_lib,
 	     erl_bifs,
 	     rec_env,
+	     sys_core_alias,
 	     sys_core_bsm,
 	     sys_core_dsetel,
 	     sys_core_fold,
@@ -67,8 +68,7 @@
 	     v3_codegen,
 	     v3_core,
 	     v3_kernel,
-	     v3_kernel_pp,
-	     v3_life
+	     v3_kernel_pp
 	    ]},
   {registered, []},
   {applications, [kernel, stdlib]},
diff --git a/bootstrap/lib/compiler/ebin/compiler.appup b/bootstrap/lib/compiler/ebin/compiler.appup
index bfea67c6dd..2973178217 100644
--- a/bootstrap/lib/compiler/ebin/compiler.appup
+++ b/bootstrap/lib/compiler/ebin/compiler.appup
@@ -16,7 +16,7 @@
 %% limitations under the License.
 %%
 %% %CopyrightEnd%
-{"7.0.4",
+{"7.1.3",
  [{<<".*">>,[{restart_application, compiler}]}],
  [{<<".*">>,[{restart_application, compiler}]}]
 }.
diff --git a/bootstrap/lib/compiler/ebin/core_lib.beam b/bootstrap/lib/compiler/ebin/core_lib.beam
index b8b5f2d2b0..f3737ecc26 100644
--- a/bootstrap/lib/compiler/ebin/core_lib.beam
+++ b/bootstrap/lib/compiler/ebin/core_lib.beam
diff --git a/bootstrap/lib/compiler/ebin/core_lint.beam b/bootstrap/lib/compiler/ebin/core_lint.beam
index f7fb759eb0..023a804f36 100644
--- a/bootstrap/lib/compiler/ebin/core_lint.beam
+++ b/bootstrap/lib/compiler/ebin/core_lint.beam
diff --git a/bootstrap/lib/compiler/ebin/core_parse.beam b/bootstrap/lib/compiler/ebin/core_parse.beam
index dda2d59d7c..b04a7b4496 100644
--- a/bootstrap/lib/compiler/ebin/core_parse.beam
+++ b/bootstrap/lib/compiler/ebin/core_parse.beam
diff --git a/bootstrap/lib/compiler/ebin/core_pp.beam b/bootstrap/lib/compiler/ebin/core_pp.beam
index 8f4137db70..45cacc510c 100644
--- a/bootstrap/lib/compiler/ebin/core_pp.beam
+++ b/bootstrap/lib/compiler/ebin/core_pp.beam
diff --git a/bootstrap/lib/compiler/ebin/core_scan.beam b/bootstrap/lib/compiler/ebin/core_scan.beam
index bec935bc5b..cd266e0f99 100644
--- a/bootstrap/lib/compiler/ebin/core_scan.beam
+++ b/bootstrap/lib/compiler/ebin/core_scan.beam
diff --git a/bootstrap/lib/compiler/ebin/erl_bifs.beam b/bootstrap/lib/compiler/ebin/erl_bifs.beam
index 6e3aad89df..060c6571af 100644
--- a/bootstrap/lib/compiler/ebin/erl_bifs.beam
+++ b/bootstrap/lib/compiler/ebin/erl_bifs.beam
diff --git a/bootstrap/lib/compiler/ebin/rec_env.beam b/bootstrap/lib/compiler/ebin/rec_env.beam
index 792fdeafc5..60e1f0401c 100644
--- a/bootstrap/lib/compiler/ebin/rec_env.beam
+++ b/bootstrap/lib/compiler/ebin/rec_env.beam
diff --git a/bootstrap/lib/compiler/ebin/sys_core_alias.beam b/bootstrap/lib/compiler/ebin/sys_core_alias.beam
new file mode 100644
index 0000000000..5794eeda81
--- /dev/null
+++ b/bootstrap/lib/compiler/ebin/sys_core_alias.beam
diff --git a/bootstrap/lib/compiler/ebin/sys_core_bsm.beam b/bootstrap/lib/compiler/ebin/sys_core_bsm.beam
index f343655448..2d2373a0ff 100644
--- a/bootstrap/lib/compiler/ebin/sys_core_bsm.beam
+++ b/bootstrap/lib/compiler/ebin/sys_core_bsm.beam
diff --git a/bootstrap/lib/compiler/ebin/sys_core_dsetel.beam b/bootstrap/lib/compiler/ebin/sys_core_dsetel.beam
index 121f2ebdd5..4a0c518337 100644
--- a/bootstrap/lib/compiler/ebin/sys_core_dsetel.beam
+++ b/bootstrap/lib/compiler/ebin/sys_core_dsetel.beam
diff --git a/bootstrap/lib/compiler/ebin/sys_core_fold.beam b/bootstrap/lib/compiler/ebin/sys_core_fold.beam
index 38ed7f6fa0..e4a69a7dc8 100644
--- a/bootstrap/lib/compiler/ebin/sys_core_fold.beam
+++ b/bootstrap/lib/compiler/ebin/sys_core_fold.beam
diff --git a/bootstrap/lib/compiler/ebin/sys_core_fold_lists.beam b/bootstrap/lib/compiler/ebin/sys_core_fold_lists.beam
index 3f72043a3f..50bd3e5096 100644
--- a/bootstrap/lib/compiler/ebin/sys_core_fold_lists.beam
+++ b/bootstrap/lib/compiler/ebin/sys_core_fold_lists.beam
diff --git a/bootstrap/lib/compiler/ebin/sys_core_inline.beam b/bootstrap/lib/compiler/ebin/sys_core_inline.beam
index f9abd6c887..a52196c764 100644
--- a/bootstrap/lib/compiler/ebin/sys_core_inline.beam
+++ b/bootstrap/lib/compiler/ebin/sys_core_inline.beam
diff --git a/bootstrap/lib/compiler/ebin/sys_pre_attributes.beam b/bootstrap/lib/compiler/ebin/sys_pre_attributes.beam
index b854db12c4..0752765115 100644
--- a/bootstrap/lib/compiler/ebin/sys_pre_attributes.beam
+++ b/bootstrap/lib/compiler/ebin/sys_pre_attributes.beam
diff --git a/bootstrap/lib/compiler/ebin/v3_codegen.beam b/bootstrap/lib/compiler/ebin/v3_codegen.beam
index b2e91c3907..17cedb8eb1 100644
--- a/bootstrap/lib/compiler/ebin/v3_codegen.beam
+++ b/bootstrap/lib/compiler/ebin/v3_codegen.beam
diff --git a/bootstrap/lib/compiler/ebin/v3_core.beam b/bootstrap/lib/compiler/ebin/v3_core.beam
index 539f5f2e61..0bd3b5b8f1 100644
--- a/bootstrap/lib/compiler/ebin/v3_core.beam
+++ b/bootstrap/lib/compiler/ebin/v3_core.beam
diff --git a/bootstrap/lib/compiler/ebin/v3_kernel.beam b/bootstrap/lib/compiler/ebin/v3_kernel.beam
index a5e95c8ecc..654dd30b41 100644
--- a/bootstrap/lib/compiler/ebin/v3_kernel.beam
+++ b/bootstrap/lib/compiler/ebin/v3_kernel.beam
diff --git a/bootstrap/lib/compiler/ebin/v3_kernel_pp.beam b/bootstrap/lib/compiler/ebin/v3_kernel_pp.beam
index 6b127e86d0..f90f26392c 100644
--- a/bootstrap/lib/compiler/ebin/v3_kernel_pp.beam
+++ b/bootstrap/lib/compiler/ebin/v3_kernel_pp.beam
diff --git a/bootstrap/lib/compiler/ebin/v3_life.beam b/bootstrap/lib/compiler/ebin/v3_life.beam
deleted file mode 100644
index c20070cf34..0000000000
--- a/bootstrap/lib/compiler/ebin/v3_life.beam
+++ /dev/null
diff --git a/bootstrap/lib/kernel/ebin/application.beam b/bootstrap/lib/kernel/ebin/application.beam
index 31c8cdb84c..58f1681fba 100644
--- a/bootstrap/lib/kernel/ebin/application.beam
+++ b/bootstrap/lib/kernel/ebin/application.beam
diff --git a/bootstrap/lib/kernel/ebin/application_controller.beam b/bootstrap/lib/kernel/ebin/application_controller.beam
index c82ed7443d..46be5c8f54 100644
--- a/bootstrap/lib/kernel/ebin/application_controller.beam
+++ b/bootstrap/lib/kernel/ebin/application_controller.beam
diff --git a/bootstrap/lib/kernel/ebin/application_master.beam b/bootstrap/lib/kernel/ebin/application_master.beam
index b76b4e4877..892d58a8b1 100644
--- a/bootstrap/lib/kernel/ebin/application_master.beam
+++ b/bootstrap/lib/kernel/ebin/application_master.beam
diff --git a/bootstrap/lib/kernel/ebin/application_starter.beam b/bootstrap/lib/kernel/ebin/application_starter.beam
index 32a6ad752d..354b96eae5 100644
--- a/bootstrap/lib/kernel/ebin/application_starter.beam
+++ b/bootstrap/lib/kernel/ebin/application_starter.beam
diff --git a/bootstrap/lib/kernel/ebin/auth.beam b/bootstrap/lib/kernel/ebin/auth.beam
index 612c23a653..cb1b5fe5b2 100644
--- a/bootstrap/lib/kernel/ebin/auth.beam
+++ b/bootstrap/lib/kernel/ebin/auth.beam
diff --git a/bootstrap/lib/kernel/ebin/code.beam b/bootstrap/lib/kernel/ebin/code.beam
index 412d341d9e..c823be3cc9 100644
--- a/bootstrap/lib/kernel/ebin/code.beam
+++ b/bootstrap/lib/kernel/ebin/code.beam
diff --git a/bootstrap/lib/kernel/ebin/code_server.beam b/bootstrap/lib/kernel/ebin/code_server.beam
index f76e90cefb..08a234da78 100644
--- a/bootstrap/lib/kernel/ebin/code_server.beam
+++ b/bootstrap/lib/kernel/ebin/code_server.beam
diff --git a/bootstrap/lib/kernel/ebin/disk_log.beam b/bootstrap/lib/kernel/ebin/disk_log.beam
index 7d4aee71ce..966a3c342f 100644
--- a/bootstrap/lib/kernel/ebin/disk_log.beam
+++ b/bootstrap/lib/kernel/ebin/disk_log.beam
diff --git a/bootstrap/lib/kernel/ebin/disk_log_1.beam b/bootstrap/lib/kernel/ebin/disk_log_1.beam
index 4b5ad17e71..984df219a4 100644
--- a/bootstrap/lib/kernel/ebin/disk_log_1.beam
+++ b/bootstrap/lib/kernel/ebin/disk_log_1.beam
diff --git a/bootstrap/lib/kernel/ebin/disk_log_server.beam b/bootstrap/lib/kernel/ebin/disk_log_server.beam
index 68d1be71a7..cc9057b149 100644
--- a/bootstrap/lib/kernel/ebin/disk_log_server.beam
+++ b/bootstrap/lib/kernel/ebin/disk_log_server.beam
diff --git a/bootstrap/lib/kernel/ebin/dist_ac.beam b/bootstrap/lib/kernel/ebin/dist_ac.beam
index ee99f41a29..6fa25d71e9 100644
--- a/bootstrap/lib/kernel/ebin/dist_ac.beam
+++ b/bootstrap/lib/kernel/ebin/dist_ac.beam
diff --git a/bootstrap/lib/kernel/ebin/dist_util.beam b/bootstrap/lib/kernel/ebin/dist_util.beam
index 6376d791cf..518b43c3df 100644
--- a/bootstrap/lib/kernel/ebin/dist_util.beam
+++ b/bootstrap/lib/kernel/ebin/dist_util.beam
diff --git a/bootstrap/lib/kernel/ebin/erl_boot_server.beam b/bootstrap/lib/kernel/ebin/erl_boot_server.beam
index ef3fe6fdea..f63e1a94f2 100644
--- a/bootstrap/lib/kernel/ebin/erl_boot_server.beam
+++ b/bootstrap/lib/kernel/ebin/erl_boot_server.beam
diff --git a/bootstrap/lib/kernel/ebin/erl_ddll.beam b/bootstrap/lib/kernel/ebin/erl_ddll.beam
index 6137ab9dd7..b672c39f5d 100644
--- a/bootstrap/lib/kernel/ebin/erl_ddll.beam
+++ b/bootstrap/lib/kernel/ebin/erl_ddll.beam
diff --git a/bootstrap/lib/kernel/ebin/erl_distribution.beam b/bootstrap/lib/kernel/ebin/erl_distribution.beam
index fcf8d7fef0..79fbb0bd49 100644
--- a/bootstrap/lib/kernel/ebin/erl_distribution.beam
+++ b/bootstrap/lib/kernel/ebin/erl_distribution.beam
diff --git a/bootstrap/lib/kernel/ebin/erl_epmd.beam b/bootstrap/lib/kernel/ebin/erl_epmd.beam
index 22725cc590..97c2d27abc 100644
--- a/bootstrap/lib/kernel/ebin/erl_epmd.beam
+++ b/bootstrap/lib/kernel/ebin/erl_epmd.beam
diff --git a/bootstrap/lib/kernel/ebin/erl_reply.beam b/bootstrap/lib/kernel/ebin/erl_reply.beam
index 6266aaa37c..25b4b6c55e 100644
--- a/bootstrap/lib/kernel/ebin/erl_reply.beam
+++ b/bootstrap/lib/kernel/ebin/erl_reply.beam
diff --git a/bootstrap/lib/kernel/ebin/erl_signal_handler.beam b/bootstrap/lib/kernel/ebin/erl_signal_handler.beam
index b2498def7f..bbb5e7fcb4 100644
--- a/bootstrap/lib/kernel/ebin/erl_signal_handler.beam
+++ b/bootstrap/lib/kernel/ebin/erl_signal_handler.beam
diff --git a/bootstrap/lib/kernel/ebin/error_logger.beam b/bootstrap/lib/kernel/ebin/error_logger.beam
index 2881ba0e9f..8293d3c354 100644
--- a/bootstrap/lib/kernel/ebin/error_logger.beam
+++ b/bootstrap/lib/kernel/ebin/error_logger.beam
diff --git a/bootstrap/lib/kernel/ebin/erts_debug.beam b/bootstrap/lib/kernel/ebin/erts_debug.beam
index a47aec4a2e..ccc39d20a5 100644
--- a/bootstrap/lib/kernel/ebin/erts_debug.beam
+++ b/bootstrap/lib/kernel/ebin/erts_debug.beam
diff --git a/bootstrap/lib/kernel/ebin/file.beam b/bootstrap/lib/kernel/ebin/file.beam
index e75200dbe3..65be0c61ae 100644
--- a/bootstrap/lib/kernel/ebin/file.beam
+++ b/bootstrap/lib/kernel/ebin/file.beam
diff --git a/bootstrap/lib/kernel/ebin/file_io_server.beam b/bootstrap/lib/kernel/ebin/file_io_server.beam
index 8d34178122..6dc1cd3e64 100644
--- a/bootstrap/lib/kernel/ebin/file_io_server.beam
+++ b/bootstrap/lib/kernel/ebin/file_io_server.beam
diff --git a/bootstrap/lib/kernel/ebin/file_server.beam b/bootstrap/lib/kernel/ebin/file_server.beam
index 5a12e2544f..f17b888898 100644
--- a/bootstrap/lib/kernel/ebin/file_server.beam
+++ b/bootstrap/lib/kernel/ebin/file_server.beam
diff --git a/bootstrap/lib/kernel/ebin/gen_sctp.beam b/bootstrap/lib/kernel/ebin/gen_sctp.beam
index e56d7fd978..dcd81b1c6f 100644
--- a/bootstrap/lib/kernel/ebin/gen_sctp.beam
+++ b/bootstrap/lib/kernel/ebin/gen_sctp.beam
diff --git a/bootstrap/lib/kernel/ebin/gen_tcp.beam b/bootstrap/lib/kernel/ebin/gen_tcp.beam
index 99ae2b0e6a..0e492978d5 100644
--- a/bootstrap/lib/kernel/ebin/gen_tcp.beam
+++ b/bootstrap/lib/kernel/ebin/gen_tcp.beam
diff --git a/bootstrap/lib/kernel/ebin/gen_udp.beam b/bootstrap/lib/kernel/ebin/gen_udp.beam
index b181c70e6a..323b6cd4bb 100644
--- a/bootstrap/lib/kernel/ebin/gen_udp.beam
+++ b/bootstrap/lib/kernel/ebin/gen_udp.beam
diff --git a/bootstrap/lib/kernel/ebin/global.beam b/bootstrap/lib/kernel/ebin/global.beam
index 9f2c77e693..7b5218d5c0 100644
--- a/bootstrap/lib/kernel/ebin/global.beam
+++ b/bootstrap/lib/kernel/ebin/global.beam
diff --git a/bootstrap/lib/kernel/ebin/global_group.beam b/bootstrap/lib/kernel/ebin/global_group.beam
index b98a472cac..f6e1cde0aa 100644
--- a/bootstrap/lib/kernel/ebin/global_group.beam
+++ b/bootstrap/lib/kernel/ebin/global_group.beam
diff --git a/bootstrap/lib/kernel/ebin/global_search.beam b/bootstrap/lib/kernel/ebin/global_search.beam
index 255886f9fe..653d2a8699 100644
--- a/bootstrap/lib/kernel/ebin/global_search.beam
+++ b/bootstrap/lib/kernel/ebin/global_search.beam
diff --git a/bootstrap/lib/kernel/ebin/group.beam b/bootstrap/lib/kernel/ebin/group.beam
index 99101fecfc..dd44980372 100644
--- a/bootstrap/lib/kernel/ebin/group.beam
+++ b/bootstrap/lib/kernel/ebin/group.beam
diff --git a/bootstrap/lib/kernel/ebin/group_history.beam b/bootstrap/lib/kernel/ebin/group_history.beam
index 1def2a5d42..9d2b59b416 100644
--- a/bootstrap/lib/kernel/ebin/group_history.beam
+++ b/bootstrap/lib/kernel/ebin/group_history.beam
diff --git a/bootstrap/lib/kernel/ebin/heart.beam b/bootstrap/lib/kernel/ebin/heart.beam
index be58924715..e015f73351 100644
--- a/bootstrap/lib/kernel/ebin/heart.beam
+++ b/bootstrap/lib/kernel/ebin/heart.beam
diff --git a/bootstrap/lib/kernel/ebin/hipe_unified_loader.beam b/bootstrap/lib/kernel/ebin/hipe_unified_loader.beam
index 06998f8dd5..5382210217 100644
--- a/bootstrap/lib/kernel/ebin/hipe_unified_loader.beam
+++ b/bootstrap/lib/kernel/ebin/hipe_unified_loader.beam
diff --git a/bootstrap/lib/kernel/ebin/inet.beam b/bootstrap/lib/kernel/ebin/inet.beam
index c4cfa54be3..2d92d7c17f 100644
--- a/bootstrap/lib/kernel/ebin/inet.beam
+++ b/bootstrap/lib/kernel/ebin/inet.beam
diff --git a/bootstrap/lib/kernel/ebin/inet6_tcp.beam b/bootstrap/lib/kernel/ebin/inet6_tcp.beam
index 2aada7f95b..300d4f3ad6 100644
--- a/bootstrap/lib/kernel/ebin/inet6_tcp.beam
+++ b/bootstrap/lib/kernel/ebin/inet6_tcp.beam
diff --git a/bootstrap/lib/kernel/ebin/inet_config.beam b/bootstrap/lib/kernel/ebin/inet_config.beam
index ab06763c7d..1da234c245 100644
--- a/bootstrap/lib/kernel/ebin/inet_config.beam
+++ b/bootstrap/lib/kernel/ebin/inet_config.beam
diff --git a/bootstrap/lib/kernel/ebin/inet_db.beam b/bootstrap/lib/kernel/ebin/inet_db.beam
index a6843431fb..b6c52bff8c 100644
--- a/bootstrap/lib/kernel/ebin/inet_db.beam
+++ b/bootstrap/lib/kernel/ebin/inet_db.beam
diff --git a/bootstrap/lib/kernel/ebin/inet_dns.beam b/bootstrap/lib/kernel/ebin/inet_dns.beam
index 4cd63fb349..f90d24dbdf 100644
--- a/bootstrap/lib/kernel/ebin/inet_dns.beam
+++ b/bootstrap/lib/kernel/ebin/inet_dns.beam
diff --git a/bootstrap/lib/kernel/ebin/inet_gethost_native.beam b/bootstrap/lib/kernel/ebin/inet_gethost_native.beam
index 177603b397..d20c0ccc8d 100644
--- a/bootstrap/lib/kernel/ebin/inet_gethost_native.beam
+++ b/bootstrap/lib/kernel/ebin/inet_gethost_native.beam
diff --git a/bootstrap/lib/kernel/ebin/inet_hosts.beam b/bootstrap/lib/kernel/ebin/inet_hosts.beam
index 6a66d00d1e..209d86690d 100644
--- a/bootstrap/lib/kernel/ebin/inet_hosts.beam
+++ b/bootstrap/lib/kernel/ebin/inet_hosts.beam
diff --git a/bootstrap/lib/kernel/ebin/inet_parse.beam b/bootstrap/lib/kernel/ebin/inet_parse.beam
index e6b9d07494..218a51d862 100644
--- a/bootstrap/lib/kernel/ebin/inet_parse.beam
+++ b/bootstrap/lib/kernel/ebin/inet_parse.beam
diff --git a/bootstrap/lib/kernel/ebin/inet_res.beam b/bootstrap/lib/kernel/ebin/inet_res.beam
index 826b5c4030..a2cacc3e07 100644
--- a/bootstrap/lib/kernel/ebin/inet_res.beam
+++ b/bootstrap/lib/kernel/ebin/inet_res.beam
diff --git a/bootstrap/lib/kernel/ebin/inet_sctp.beam b/bootstrap/lib/kernel/ebin/inet_sctp.beam
index a12c138257..c844e2ee34 100644
--- a/bootstrap/lib/kernel/ebin/inet_sctp.beam
+++ b/bootstrap/lib/kernel/ebin/inet_sctp.beam
diff --git a/bootstrap/lib/kernel/ebin/inet_tcp.beam b/bootstrap/lib/kernel/ebin/inet_tcp.beam
index 6199354874..55b65ada4e 100644
--- a/bootstrap/lib/kernel/ebin/inet_tcp.beam
+++ b/bootstrap/lib/kernel/ebin/inet_tcp.beam
diff --git a/bootstrap/lib/kernel/ebin/inet_tcp_dist.beam b/bootstrap/lib/kernel/ebin/inet_tcp_dist.beam
index f8a95de32c..603f26de67 100644
--- a/bootstrap/lib/kernel/ebin/inet_tcp_dist.beam
+++ b/bootstrap/lib/kernel/ebin/inet_tcp_dist.beam
diff --git a/bootstrap/lib/kernel/ebin/inet_udp.beam b/bootstrap/lib/kernel/ebin/inet_udp.beam
index 17fef57714..46ce14c110 100644
--- a/bootstrap/lib/kernel/ebin/inet_udp.beam
+++ b/bootstrap/lib/kernel/ebin/inet_udp.beam
diff --git a/bootstrap/lib/kernel/ebin/kernel.app b/bootstrap/lib/kernel/ebin/kernel.app
index b888d914e8..55445f83c6 100644
--- a/bootstrap/lib/kernel/ebin/kernel.app
+++ b/bootstrap/lib/kernel/ebin/kernel.app
@@ -22,7 +22,7 @@
 {application, kernel,
  [
   {description, "ERTS  CXC 138 10"},
-  {vsn, "5.3.1"},
+  {vsn, "5.4"},
   {modules, [application,
 	     application_controller,
 	     application_master,
@@ -88,6 +88,13 @@
              inet_udp,
 	     inet_sctp,
              pg2,
+             raw_file_io,
+             raw_file_io_compressed,
+             raw_file_io_deflate,
+             raw_file_io_delayed,
+             raw_file_io_inflate,
+             raw_file_io_list,
+             raw_file_io_raw,
 	     seq_trace,
 	     standard_error,
 	     wrap_log_reader]},
@@ -120,6 +127,6 @@
   {applications, []},
   {env, [{error_logger, tty}]},
   {mod, {kernel, []}},
-  {runtime_dependencies, ["erts-9.1", "stdlib-3.0", "sasl-3.0"]}
+  {runtime_dependencies, ["erts-10.0", "stdlib-3.5", "sasl-3.0"]}
  ]
 }.
diff --git a/bootstrap/lib/kernel/ebin/kernel.appup b/bootstrap/lib/kernel/ebin/kernel.appup
index d822674939..7ddb592671 100644
--- a/bootstrap/lib/kernel/ebin/kernel.appup
+++ b/bootstrap/lib/kernel/ebin/kernel.appup
@@ -16,9 +16,9 @@
 %% limitations under the License.
 %%
 %% %CopyrightEnd%
-{"5.3.1",
+{"5.4",
  %% Up from - max one major revision back
- [{<<"5\\.[0-3](\\.[0-9]+)*">>,[restart_new_emulator]}], % OTP-19.*, OTP-20.0
+ [{<<"5\\.3(\\.[0-9]+)*">>,[restart_new_emulator]}], % OTP-20.*
  %% Down to - max one major revision back
- [{<<"5\\.[0-3](\\.[0-9]+)*">>,[restart_new_emulator]}]  % OTP-19.*, OTP-20.0
+ [{<<"5\\.3(\\.[0-9]+)*">>,[restart_new_emulator]}]  % OTP-20.*
 }.
diff --git a/bootstrap/lib/kernel/ebin/kernel.beam b/bootstrap/lib/kernel/ebin/kernel.beam
index 4000653c44..0a997bddd4 100644
--- a/bootstrap/lib/kernel/ebin/kernel.beam
+++ b/bootstrap/lib/kernel/ebin/kernel.beam
diff --git a/bootstrap/lib/kernel/ebin/kernel_config.beam b/bootstrap/lib/kernel/ebin/kernel_config.beam
index d669a101a0..ffb06f2aef 100644
--- a/bootstrap/lib/kernel/ebin/kernel_config.beam
+++ b/bootstrap/lib/kernel/ebin/kernel_config.beam
diff --git a/bootstrap/lib/kernel/ebin/local_tcp.beam b/bootstrap/lib/kernel/ebin/local_tcp.beam
index 151ec3cd4e..02c5848f11 100644
--- a/bootstrap/lib/kernel/ebin/local_tcp.beam
+++ b/bootstrap/lib/kernel/ebin/local_tcp.beam
diff --git a/bootstrap/lib/kernel/ebin/net_adm.beam b/bootstrap/lib/kernel/ebin/net_adm.beam
index 0597590966..f2eac80afe 100644
--- a/bootstrap/lib/kernel/ebin/net_adm.beam
+++ b/bootstrap/lib/kernel/ebin/net_adm.beam
diff --git a/bootstrap/lib/kernel/ebin/net_kernel.beam b/bootstrap/lib/kernel/ebin/net_kernel.beam
index b3c5f4ba29..f352e2c064 100644
--- a/bootstrap/lib/kernel/ebin/net_kernel.beam
+++ b/bootstrap/lib/kernel/ebin/net_kernel.beam
diff --git a/bootstrap/lib/kernel/ebin/os.beam b/bootstrap/lib/kernel/ebin/os.beam
index 0bc6403871..98c44e8fba 100644
--- a/bootstrap/lib/kernel/ebin/os.beam
+++ b/bootstrap/lib/kernel/ebin/os.beam
diff --git a/bootstrap/lib/kernel/ebin/pg2.beam b/bootstrap/lib/kernel/ebin/pg2.beam
index b99d8ba810..4d1a79a94c 100644
--- a/bootstrap/lib/kernel/ebin/pg2.beam
+++ b/bootstrap/lib/kernel/ebin/pg2.beam
diff --git a/bootstrap/lib/kernel/ebin/ram_file.beam b/bootstrap/lib/kernel/ebin/ram_file.beam
index c867e48002..ca476c5f7d 100644
--- a/bootstrap/lib/kernel/ebin/ram_file.beam
+++ b/bootstrap/lib/kernel/ebin/ram_file.beam
diff --git a/bootstrap/lib/kernel/ebin/raw_file_io.beam b/bootstrap/lib/kernel/ebin/raw_file_io.beam
new file mode 100644
index 0000000000..734a051882
--- /dev/null
+++ b/bootstrap/lib/kernel/ebin/raw_file_io.beam
diff --git a/bootstrap/lib/kernel/ebin/raw_file_io_compressed.beam b/bootstrap/lib/kernel/ebin/raw_file_io_compressed.beam
new file mode 100644
index 0000000000..caa3d9ac6b
--- /dev/null
+++ b/bootstrap/lib/kernel/ebin/raw_file_io_compressed.beam
diff --git a/bootstrap/lib/kernel/ebin/raw_file_io_deflate.beam b/bootstrap/lib/kernel/ebin/raw_file_io_deflate.beam
new file mode 100644
index 0000000000..62c28195a3
--- /dev/null
+++ b/bootstrap/lib/kernel/ebin/raw_file_io_deflate.beam
diff --git a/bootstrap/lib/kernel/ebin/raw_file_io_delayed.beam b/bootstrap/lib/kernel/ebin/raw_file_io_delayed.beam
new file mode 100644
index 0000000000..3090c454bf
--- /dev/null
+++ b/bootstrap/lib/kernel/ebin/raw_file_io_delayed.beam
diff --git a/bootstrap/lib/kernel/ebin/raw_file_io_inflate.beam b/bootstrap/lib/kernel/ebin/raw_file_io_inflate.beam
new file mode 100644
index 0000000000..1ed3abc73d
--- /dev/null
+++ b/bootstrap/lib/kernel/ebin/raw_file_io_inflate.beam
diff --git a/bootstrap/lib/kernel/ebin/raw_file_io_list.beam b/bootstrap/lib/kernel/ebin/raw_file_io_list.beam
new file mode 100644
index 0000000000..283f3b892d
--- /dev/null
+++ b/bootstrap/lib/kernel/ebin/raw_file_io_list.beam
diff --git a/bootstrap/lib/kernel/ebin/raw_file_io_raw.beam b/bootstrap/lib/kernel/ebin/raw_file_io_raw.beam
new file mode 100644
index 0000000000..b47a67055d
--- /dev/null
+++ b/bootstrap/lib/kernel/ebin/raw_file_io_raw.beam
diff --git a/bootstrap/lib/kernel/ebin/rpc.beam b/bootstrap/lib/kernel/ebin/rpc.beam
index 909cf49410..abaec4bbd8 100644
--- a/bootstrap/lib/kernel/ebin/rpc.beam
+++ b/bootstrap/lib/kernel/ebin/rpc.beam
diff --git a/bootstrap/lib/kernel/ebin/seq_trace.beam b/bootstrap/lib/kernel/ebin/seq_trace.beam
index 3de0a5d940..1d1e277bf3 100644
--- a/bootstrap/lib/kernel/ebin/seq_trace.beam
+++ b/bootstrap/lib/kernel/ebin/seq_trace.beam
diff --git a/bootstrap/lib/kernel/ebin/standard_error.beam b/bootstrap/lib/kernel/ebin/standard_error.beam
index 015f2c19cb..b35659983e 100644
--- a/bootstrap/lib/kernel/ebin/standard_error.beam
+++ b/bootstrap/lib/kernel/ebin/standard_error.beam
diff --git a/bootstrap/lib/kernel/ebin/user.beam b/bootstrap/lib/kernel/ebin/user.beam
index cf4e55254c..006fd607c0 100644
--- a/bootstrap/lib/kernel/ebin/user.beam
+++ b/bootstrap/lib/kernel/ebin/user.beam
diff --git a/bootstrap/lib/kernel/ebin/user_drv.beam b/bootstrap/lib/kernel/ebin/user_drv.beam
index b204dced59..d6bb443081 100644
--- a/bootstrap/lib/kernel/ebin/user_drv.beam
+++ b/bootstrap/lib/kernel/ebin/user_drv.beam
diff --git a/bootstrap/lib/kernel/ebin/user_sup.beam b/bootstrap/lib/kernel/ebin/user_sup.beam
index f5e0d1112a..df6a0be44b 100644
--- a/bootstrap/lib/kernel/ebin/user_sup.beam
+++ b/bootstrap/lib/kernel/ebin/user_sup.beam
diff --git a/bootstrap/lib/kernel/ebin/wrap_log_reader.beam b/bootstrap/lib/kernel/ebin/wrap_log_reader.beam
index 57038df042..40f3ecdfc7 100644
--- a/bootstrap/lib/kernel/ebin/wrap_log_reader.beam
+++ b/bootstrap/lib/kernel/ebin/wrap_log_reader.beam
diff --git a/bootstrap/lib/kernel/include/dist.hrl b/bootstrap/lib/kernel/include/dist.hrl
index d6bccdf474..db4a5eaebc 100644
--- a/bootstrap/lib/kernel/include/dist.hrl
+++ b/bootstrap/lib/kernel/include/dist.hrl
@@ -40,3 +40,33 @@
 -define(DFLAG_UTF8_ATOMS, 16#10000).
 -define(DFLAG_MAP_TAG, 16#20000).
 -define(DFLAG_BIG_CREATION, 16#40000).
+-define(DFLAG_SEND_SENDER, 16#80000).
+
+%% DFLAGs that require strict ordering or:ed together...
+-define(DFLAGS_STRICT_ORDER_DELIVERY,
+        ?DFLAG_DIST_HDR_ATOM_CACHE).
+
+
+%% Also update dflag2str() in ../src/dist_util.erl
+%% when adding flags...
+
+-define(DFLAGS_ALL,
+        (?DFLAG_PUBLISHED
+             bor ?DFLAG_ATOM_CACHE
+             bor ?DFLAG_EXTENDED_REFERENCES
+             bor ?DFLAG_DIST_MONITOR
+             bor ?DFLAG_FUN_TAGS
+             bor ?DFLAG_DIST_MONITOR_NAME
+             bor ?DFLAG_HIDDEN_ATOM_CACHE
+             bor ?DFLAG_NEW_FUN_TAGS
+             bor ?DFLAG_EXTENDED_PIDS_PORTS
+             bor ?DFLAG_EXPORT_PTR_TAG
+             bor ?DFLAG_BIT_BINARIES
+             bor ?DFLAG_NEW_FLOATS
+             bor ?DFLAG_UNICODE_IO
+             bor ?DFLAG_DIST_HDR_ATOM_CACHE
+             bor ?DFLAG_SMALL_ATOM_TAGS
+             bor ?DFLAG_UTF8_ATOMS
+             bor ?DFLAG_MAP_TAG
+             bor ?DFLAG_BIG_CREATION
+             bor ?DFLAG_SEND_SENDER)).
diff --git a/bootstrap/lib/kernel/include/dist_util.hrl b/bootstrap/lib/kernel/include/dist_util.hrl
index e3d2fe0eb6..eeb0f8dd43 100644
--- a/bootstrap/lib/kernel/include/dist_util.hrl
+++ b/bootstrap/lib/kernel/include/dist_util.hrl
@@ -29,9 +29,9 @@
 -endif.
 
 -ifdef(dist_trace).
--define(trace(Fmt,Args), io:format("~p ~p:~s",[erlang:timestamp(),node(),lists:flatten(io_lib:format(Fmt, Args))])).
+-define(trace(Fmt,Args), io:format("~p ~p:~s",[erlang:convert_time_unit(erlang:monotonic_time()-erlang:system_info(start_time), native, microsecond),node(),lists:flatten(io_lib:format(Fmt, Args))])).
 % Use the one below for config-file (early boot) connection tracing
-%-define(trace(Fmt,Args), erlang:display([erlang:now(),node(),lists:flatten(io_lib:format(Fmt, Args))])).
+%-define(trace(Fmt,Args), erlang:display([erlang:convert_time_unit(erlang:monotonic_time()-erlang:system_info(start_time), native, microsecond),node(),lists:flatten(io_lib:format(Fmt, Args))])).
 -define(trace_factor,8).
 -else.
 -define(trace(Fmt,Args), ok).
@@ -78,7 +78,13 @@
 
 	  %% New in kernel-5.1 (OTP 19.1):
 	  mf_setopts,        %% netkernel:setopts on active connection
-	  mf_getopts         %% netkernel:getopts on active connection
+	  mf_getopts,         %% netkernel:getopts on active connection
+
+          %% New in kernel-6.0 (OTP 21.0)
+          f_handshake_complete, %% Notify handshake complete
+          add_flags,         %% dflags to add
+          reject_flags,      %% dflags not to use (not all can be rejected)
+          require_flags     %% dflags that are required
 }).
 	  
 
diff --git a/bootstrap/lib/stdlib/ebin/array.beam b/bootstrap/lib/stdlib/ebin/array.beam
index ce8145374e..904513df6b 100644
--- a/bootstrap/lib/stdlib/ebin/array.beam
+++ b/bootstrap/lib/stdlib/ebin/array.beam
diff --git a/bootstrap/lib/stdlib/ebin/base64.beam b/bootstrap/lib/stdlib/ebin/base64.beam
index 00c908062a..8670e9cf7f 100644
--- a/bootstrap/lib/stdlib/ebin/base64.beam
+++ b/bootstrap/lib/stdlib/ebin/base64.beam
diff --git a/bootstrap/lib/stdlib/ebin/beam_lib.beam b/bootstrap/lib/stdlib/ebin/beam_lib.beam
index 3625f9349e..9282e46c90 100644
--- a/bootstrap/lib/stdlib/ebin/beam_lib.beam
+++ b/bootstrap/lib/stdlib/ebin/beam_lib.beam
diff --git a/bootstrap/lib/stdlib/ebin/binary.beam b/bootstrap/lib/stdlib/ebin/binary.beam
index 64c0538908..85fc484c32 100644
--- a/bootstrap/lib/stdlib/ebin/binary.beam
+++ b/bootstrap/lib/stdlib/ebin/binary.beam
diff --git a/bootstrap/lib/stdlib/ebin/c.beam b/bootstrap/lib/stdlib/ebin/c.beam
index 0af4164bf5..b9be0ec3c8 100644
--- a/bootstrap/lib/stdlib/ebin/c.beam
+++ b/bootstrap/lib/stdlib/ebin/c.beam
diff --git a/bootstrap/lib/stdlib/ebin/calendar.beam b/bootstrap/lib/stdlib/ebin/calendar.beam
index 62e51ef137..ec7237faeb 100644
--- a/bootstrap/lib/stdlib/ebin/calendar.beam
+++ b/bootstrap/lib/stdlib/ebin/calendar.beam
diff --git a/bootstrap/lib/stdlib/ebin/dets.beam b/bootstrap/lib/stdlib/ebin/dets.beam
index ee5786ea39..e104c135f3 100644
--- a/bootstrap/lib/stdlib/ebin/dets.beam
+++ b/bootstrap/lib/stdlib/ebin/dets.beam
diff --git a/bootstrap/lib/stdlib/ebin/dets_server.beam b/bootstrap/lib/stdlib/ebin/dets_server.beam
index a447af9bc4..389140d14f 100644
--- a/bootstrap/lib/stdlib/ebin/dets_server.beam
+++ b/bootstrap/lib/stdlib/ebin/dets_server.beam
diff --git a/bootstrap/lib/stdlib/ebin/dets_utils.beam b/bootstrap/lib/stdlib/ebin/dets_utils.beam
index ab06a2b8b2..458a7a964f 100644
--- a/bootstrap/lib/stdlib/ebin/dets_utils.beam
+++ b/bootstrap/lib/stdlib/ebin/dets_utils.beam
diff --git a/bootstrap/lib/stdlib/ebin/dets_v9.beam b/bootstrap/lib/stdlib/ebin/dets_v9.beam
index 6eb576ec50..59ff4675bb 100644
--- a/bootstrap/lib/stdlib/ebin/dets_v9.beam
+++ b/bootstrap/lib/stdlib/ebin/dets_v9.beam
diff --git a/bootstrap/lib/stdlib/ebin/dict.beam b/bootstrap/lib/stdlib/ebin/dict.beam
index 08fd0f07a7..72fd947f5e 100644
--- a/bootstrap/lib/stdlib/ebin/dict.beam
+++ b/bootstrap/lib/stdlib/ebin/dict.beam
diff --git a/bootstrap/lib/stdlib/ebin/digraph.beam b/bootstrap/lib/stdlib/ebin/digraph.beam
index 0a2e8f20b4..62b7c6d2e6 100644
--- a/bootstrap/lib/stdlib/ebin/digraph.beam
+++ b/bootstrap/lib/stdlib/ebin/digraph.beam
diff --git a/bootstrap/lib/stdlib/ebin/digraph_utils.beam b/bootstrap/lib/stdlib/ebin/digraph_utils.beam
index 11ec1d3b7c..6b0158ce48 100644
--- a/bootstrap/lib/stdlib/ebin/digraph_utils.beam
+++ b/bootstrap/lib/stdlib/ebin/digraph_utils.beam
diff --git a/bootstrap/lib/stdlib/ebin/edlin.beam b/bootstrap/lib/stdlib/ebin/edlin.beam
index d6a9bd1814..6dd4f50887 100644
--- a/bootstrap/lib/stdlib/ebin/edlin.beam
+++ b/bootstrap/lib/stdlib/ebin/edlin.beam
diff --git a/bootstrap/lib/stdlib/ebin/edlin_expand.beam b/bootstrap/lib/stdlib/ebin/edlin_expand.beam
index 8579266b8f..db7a6780ca 100644
--- a/bootstrap/lib/stdlib/ebin/edlin_expand.beam
+++ b/bootstrap/lib/stdlib/ebin/edlin_expand.beam
diff --git a/bootstrap/lib/stdlib/ebin/epp.beam b/bootstrap/lib/stdlib/ebin/epp.beam
index b5c98392d5..117acec27f 100644
--- a/bootstrap/lib/stdlib/ebin/epp.beam
+++ b/bootstrap/lib/stdlib/ebin/epp.beam
diff --git a/bootstrap/lib/stdlib/ebin/erl_abstract_code.beam b/bootstrap/lib/stdlib/ebin/erl_abstract_code.beam
index 7db89cb79e..8999166466 100644
--- a/bootstrap/lib/stdlib/ebin/erl_abstract_code.beam
+++ b/bootstrap/lib/stdlib/ebin/erl_abstract_code.beam
diff --git a/bootstrap/lib/stdlib/ebin/erl_anno.beam b/bootstrap/lib/stdlib/ebin/erl_anno.beam
index 716a2b63df..122f562563 100644
--- a/bootstrap/lib/stdlib/ebin/erl_anno.beam
+++ b/bootstrap/lib/stdlib/ebin/erl_anno.beam
diff --git a/bootstrap/lib/stdlib/ebin/erl_bits.beam b/bootstrap/lib/stdlib/ebin/erl_bits.beam
index 944b7e3d0f..11ab24851e 100644
--- a/bootstrap/lib/stdlib/ebin/erl_bits.beam
+++ b/bootstrap/lib/stdlib/ebin/erl_bits.beam
diff --git a/bootstrap/lib/stdlib/ebin/erl_compile.beam b/bootstrap/lib/stdlib/ebin/erl_compile.beam
index d39b5a29b0..ed41f0347f 100644
--- a/bootstrap/lib/stdlib/ebin/erl_compile.beam
+++ b/bootstrap/lib/stdlib/ebin/erl_compile.beam
diff --git a/bootstrap/lib/stdlib/ebin/erl_eval.beam b/bootstrap/lib/stdlib/ebin/erl_eval.beam
index 37832662df..72c9d51cf9 100644
--- a/bootstrap/lib/stdlib/ebin/erl_eval.beam
+++ b/bootstrap/lib/stdlib/ebin/erl_eval.beam
diff --git a/bootstrap/lib/stdlib/ebin/erl_expand_records.beam b/bootstrap/lib/stdlib/ebin/erl_expand_records.beam
index 902a5d545a..a22c1eac2f 100644
--- a/bootstrap/lib/stdlib/ebin/erl_expand_records.beam
+++ b/bootstrap/lib/stdlib/ebin/erl_expand_records.beam
diff --git a/bootstrap/lib/stdlib/ebin/erl_internal.beam b/bootstrap/lib/stdlib/ebin/erl_internal.beam
index f58974b75f..fd21c22f81 100644
--- a/bootstrap/lib/stdlib/ebin/erl_internal.beam
+++ b/bootstrap/lib/stdlib/ebin/erl_internal.beam
diff --git a/bootstrap/lib/stdlib/ebin/erl_lint.beam b/bootstrap/lib/stdlib/ebin/erl_lint.beam
index f79c57877c..c194bda041 100644
--- a/bootstrap/lib/stdlib/ebin/erl_lint.beam
+++ b/bootstrap/lib/stdlib/ebin/erl_lint.beam
diff --git a/bootstrap/lib/stdlib/ebin/erl_parse.beam b/bootstrap/lib/stdlib/ebin/erl_parse.beam
index d419485285..7f0e173b3d 100644
--- a/bootstrap/lib/stdlib/ebin/erl_parse.beam
+++ b/bootstrap/lib/stdlib/ebin/erl_parse.beam
diff --git a/bootstrap/lib/stdlib/ebin/erl_pp.beam b/bootstrap/lib/stdlib/ebin/erl_pp.beam
index 50514737fc..b2104c97df 100644
--- a/bootstrap/lib/stdlib/ebin/erl_pp.beam
+++ b/bootstrap/lib/stdlib/ebin/erl_pp.beam
diff --git a/bootstrap/lib/stdlib/ebin/erl_scan.beam b/bootstrap/lib/stdlib/ebin/erl_scan.beam
index 38d6c42ba2..982f377630 100644
--- a/bootstrap/lib/stdlib/ebin/erl_scan.beam
+++ b/bootstrap/lib/stdlib/ebin/erl_scan.beam
diff --git a/bootstrap/lib/stdlib/ebin/erl_tar.beam b/bootstrap/lib/stdlib/ebin/erl_tar.beam
index b48a01a7b7..5ccd9e3bc5 100644
--- a/bootstrap/lib/stdlib/ebin/erl_tar.beam
+++ b/bootstrap/lib/stdlib/ebin/erl_tar.beam
diff --git a/bootstrap/lib/stdlib/ebin/error_logger_file_h.beam b/bootstrap/lib/stdlib/ebin/error_logger_file_h.beam
index f9df6de595..04d3fe7952 100644
--- a/bootstrap/lib/stdlib/ebin/error_logger_file_h.beam
+++ b/bootstrap/lib/stdlib/ebin/error_logger_file_h.beam
diff --git a/bootstrap/lib/stdlib/ebin/error_logger_tty_h.beam b/bootstrap/lib/stdlib/ebin/error_logger_tty_h.beam
index 7c9a264e4e..94368ffd53 100644
--- a/bootstrap/lib/stdlib/ebin/error_logger_tty_h.beam
+++ b/bootstrap/lib/stdlib/ebin/error_logger_tty_h.beam
diff --git a/bootstrap/lib/stdlib/ebin/escript.beam b/bootstrap/lib/stdlib/ebin/escript.beam
index a80e141a9a..213393794d 100644
--- a/bootstrap/lib/stdlib/ebin/escript.beam
+++ b/bootstrap/lib/stdlib/ebin/escript.beam
diff --git a/bootstrap/lib/stdlib/ebin/ets.beam b/bootstrap/lib/stdlib/ebin/ets.beam
index 6345b6b2da..d82ec7d3c0 100644
--- a/bootstrap/lib/stdlib/ebin/ets.beam
+++ b/bootstrap/lib/stdlib/ebin/ets.beam
diff --git a/bootstrap/lib/stdlib/ebin/eval_bits.beam b/bootstrap/lib/stdlib/ebin/eval_bits.beam
index 472990bbbb..fb695d86fe 100644
--- a/bootstrap/lib/stdlib/ebin/eval_bits.beam
+++ b/bootstrap/lib/stdlib/ebin/eval_bits.beam
diff --git a/bootstrap/lib/stdlib/ebin/file_sorter.beam b/bootstrap/lib/stdlib/ebin/file_sorter.beam
index 84fee9944c..e16f904d3c 100644
--- a/bootstrap/lib/stdlib/ebin/file_sorter.beam
+++ b/bootstrap/lib/stdlib/ebin/file_sorter.beam
diff --git a/bootstrap/lib/stdlib/ebin/filelib.beam b/bootstrap/lib/stdlib/ebin/filelib.beam
index 32496b6ceb..87810111b6 100644
--- a/bootstrap/lib/stdlib/ebin/filelib.beam
+++ b/bootstrap/lib/stdlib/ebin/filelib.beam
diff --git a/bootstrap/lib/stdlib/ebin/filename.beam b/bootstrap/lib/stdlib/ebin/filename.beam
index 76e1755ba4..03de7c6152 100644
--- a/bootstrap/lib/stdlib/ebin/filename.beam
+++ b/bootstrap/lib/stdlib/ebin/filename.beam
diff --git a/bootstrap/lib/stdlib/ebin/gb_sets.beam b/bootstrap/lib/stdlib/ebin/gb_sets.beam
index 4dec91bb83..97405caca0 100644
--- a/bootstrap/lib/stdlib/ebin/gb_sets.beam
+++ b/bootstrap/lib/stdlib/ebin/gb_sets.beam
diff --git a/bootstrap/lib/stdlib/ebin/gb_trees.beam b/bootstrap/lib/stdlib/ebin/gb_trees.beam
index dd3a7076bc..e62ee69cec 100644
--- a/bootstrap/lib/stdlib/ebin/gb_trees.beam
+++ b/bootstrap/lib/stdlib/ebin/gb_trees.beam
diff --git a/bootstrap/lib/stdlib/ebin/gen.beam b/bootstrap/lib/stdlib/ebin/gen.beam
index 7da423e0c6..de761e2ccb 100644
--- a/bootstrap/lib/stdlib/ebin/gen.beam
+++ b/bootstrap/lib/stdlib/ebin/gen.beam
diff --git a/bootstrap/lib/stdlib/ebin/gen_event.beam b/bootstrap/lib/stdlib/ebin/gen_event.beam
index ec537eb4fb..dd24351d71 100644
--- a/bootstrap/lib/stdlib/ebin/gen_event.beam
+++ b/bootstrap/lib/stdlib/ebin/gen_event.beam
diff --git a/bootstrap/lib/stdlib/ebin/gen_fsm.beam b/bootstrap/lib/stdlib/ebin/gen_fsm.beam
index fc315592aa..132b948434 100644
--- a/bootstrap/lib/stdlib/ebin/gen_fsm.beam
+++ b/bootstrap/lib/stdlib/ebin/gen_fsm.beam
diff --git a/bootstrap/lib/stdlib/ebin/gen_server.beam b/bootstrap/lib/stdlib/ebin/gen_server.beam
index d84e351fe3..68f678ff03 100644
--- a/bootstrap/lib/stdlib/ebin/gen_server.beam
+++ b/bootstrap/lib/stdlib/ebin/gen_server.beam
diff --git a/bootstrap/lib/stdlib/ebin/gen_statem.beam b/bootstrap/lib/stdlib/ebin/gen_statem.beam
index 56cf9402f4..05932db2f2 100644
--- a/bootstrap/lib/stdlib/ebin/gen_statem.beam
+++ b/bootstrap/lib/stdlib/ebin/gen_statem.beam
diff --git a/bootstrap/lib/stdlib/ebin/io.beam b/bootstrap/lib/stdlib/ebin/io.beam
index f582fa67e9..40109e2a13 100644
--- a/bootstrap/lib/stdlib/ebin/io.beam
+++ b/bootstrap/lib/stdlib/ebin/io.beam
diff --git a/bootstrap/lib/stdlib/ebin/io_lib.beam b/bootstrap/lib/stdlib/ebin/io_lib.beam
index 7e16c0503d..bb018a3dbb 100644
--- a/bootstrap/lib/stdlib/ebin/io_lib.beam
+++ b/bootstrap/lib/stdlib/ebin/io_lib.beam
diff --git a/bootstrap/lib/stdlib/ebin/io_lib_format.beam b/bootstrap/lib/stdlib/ebin/io_lib_format.beam
index 9cffe25cc3..a24adeab6d 100644
--- a/bootstrap/lib/stdlib/ebin/io_lib_format.beam
+++ b/bootstrap/lib/stdlib/ebin/io_lib_format.beam
diff --git a/bootstrap/lib/stdlib/ebin/io_lib_fread.beam b/bootstrap/lib/stdlib/ebin/io_lib_fread.beam
index 162bec0220..2eebe1c85d 100644
--- a/bootstrap/lib/stdlib/ebin/io_lib_fread.beam
+++ b/bootstrap/lib/stdlib/ebin/io_lib_fread.beam
diff --git a/bootstrap/lib/stdlib/ebin/io_lib_pretty.beam b/bootstrap/lib/stdlib/ebin/io_lib_pretty.beam
index 63290e5490..a51f7c896e 100644
--- a/bootstrap/lib/stdlib/ebin/io_lib_pretty.beam
+++ b/bootstrap/lib/stdlib/ebin/io_lib_pretty.beam
diff --git a/bootstrap/lib/stdlib/ebin/lib.beam b/bootstrap/lib/stdlib/ebin/lib.beam
index 2e050a2ab5..dc99df9c5f 100644
--- a/bootstrap/lib/stdlib/ebin/lib.beam
+++ b/bootstrap/lib/stdlib/ebin/lib.beam
diff --git a/bootstrap/lib/stdlib/ebin/lists.beam b/bootstrap/lib/stdlib/ebin/lists.beam
index 9e47a6b1eb..c95243debf 100644
--- a/bootstrap/lib/stdlib/ebin/lists.beam
+++ b/bootstrap/lib/stdlib/ebin/lists.beam
diff --git a/bootstrap/lib/stdlib/ebin/log_mf_h.beam b/bootstrap/lib/stdlib/ebin/log_mf_h.beam
index 85feb97748..985a9502f5 100644
--- a/bootstrap/lib/stdlib/ebin/log_mf_h.beam
+++ b/bootstrap/lib/stdlib/ebin/log_mf_h.beam
diff --git a/bootstrap/lib/stdlib/ebin/maps.beam b/bootstrap/lib/stdlib/ebin/maps.beam
index 70715a5dd2..85e997bb1c 100644
--- a/bootstrap/lib/stdlib/ebin/maps.beam
+++ b/bootstrap/lib/stdlib/ebin/maps.beam
diff --git a/bootstrap/lib/stdlib/ebin/ms_transform.beam b/bootstrap/lib/stdlib/ebin/ms_transform.beam
index cdc1c8d23f..d924a50d82 100644
--- a/bootstrap/lib/stdlib/ebin/ms_transform.beam
+++ b/bootstrap/lib/stdlib/ebin/ms_transform.beam
diff --git a/bootstrap/lib/stdlib/ebin/orddict.beam b/bootstrap/lib/stdlib/ebin/orddict.beam
index a97f19b2cd..57a23fbe98 100644
--- a/bootstrap/lib/stdlib/ebin/orddict.beam
+++ b/bootstrap/lib/stdlib/ebin/orddict.beam
diff --git a/bootstrap/lib/stdlib/ebin/ordsets.beam b/bootstrap/lib/stdlib/ebin/ordsets.beam
index 487a232b15..b966590d8d 100644
--- a/bootstrap/lib/stdlib/ebin/ordsets.beam
+++ b/bootstrap/lib/stdlib/ebin/ordsets.beam
diff --git a/bootstrap/lib/stdlib/ebin/otp_internal.beam b/bootstrap/lib/stdlib/ebin/otp_internal.beam
index 620f2ea8f8..166574e0f6 100644
--- a/bootstrap/lib/stdlib/ebin/otp_internal.beam
+++ b/bootstrap/lib/stdlib/ebin/otp_internal.beam
diff --git a/bootstrap/lib/stdlib/ebin/pool.beam b/bootstrap/lib/stdlib/ebin/pool.beam
index e43f0d4265..c6b6e8314d 100644
--- a/bootstrap/lib/stdlib/ebin/pool.beam
+++ b/bootstrap/lib/stdlib/ebin/pool.beam
diff --git a/bootstrap/lib/stdlib/ebin/proc_lib.beam b/bootstrap/lib/stdlib/ebin/proc_lib.beam
index 7c9cfad78e..90659c9df9 100644
--- a/bootstrap/lib/stdlib/ebin/proc_lib.beam
+++ b/bootstrap/lib/stdlib/ebin/proc_lib.beam
diff --git a/bootstrap/lib/stdlib/ebin/proplists.beam b/bootstrap/lib/stdlib/ebin/proplists.beam
index f3a49e1a90..b00ac13e9d 100644
--- a/bootstrap/lib/stdlib/ebin/proplists.beam
+++ b/bootstrap/lib/stdlib/ebin/proplists.beam
diff --git a/bootstrap/lib/stdlib/ebin/qlc.beam b/bootstrap/lib/stdlib/ebin/qlc.beam
index ea0d5265b8..9f3daf5dc7 100644
--- a/bootstrap/lib/stdlib/ebin/qlc.beam
+++ b/bootstrap/lib/stdlib/ebin/qlc.beam
diff --git a/bootstrap/lib/stdlib/ebin/qlc_pt.beam b/bootstrap/lib/stdlib/ebin/qlc_pt.beam
index 64b750856e..e287e2002f 100644
--- a/bootstrap/lib/stdlib/ebin/qlc_pt.beam
+++ b/bootstrap/lib/stdlib/ebin/qlc_pt.beam
diff --git a/bootstrap/lib/stdlib/ebin/queue.beam b/bootstrap/lib/stdlib/ebin/queue.beam
index ab31525e31..ca0c6794ca 100644
--- a/bootstrap/lib/stdlib/ebin/queue.beam
+++ b/bootstrap/lib/stdlib/ebin/queue.beam
diff --git a/bootstrap/lib/stdlib/ebin/rand.beam b/bootstrap/lib/stdlib/ebin/rand.beam
index 9141567b43..7921ac2497 100644
--- a/bootstrap/lib/stdlib/ebin/rand.beam
+++ b/bootstrap/lib/stdlib/ebin/rand.beam
diff --git a/bootstrap/lib/stdlib/ebin/re.beam b/bootstrap/lib/stdlib/ebin/re.beam
index ad5c7ac20f..415ff7bb43 100644
--- a/bootstrap/lib/stdlib/ebin/re.beam
+++ b/bootstrap/lib/stdlib/ebin/re.beam
diff --git a/bootstrap/lib/stdlib/ebin/sets.beam b/bootstrap/lib/stdlib/ebin/sets.beam
index 48165b7598..b4a15dc9db 100644
--- a/bootstrap/lib/stdlib/ebin/sets.beam
+++ b/bootstrap/lib/stdlib/ebin/sets.beam
diff --git a/bootstrap/lib/stdlib/ebin/shell.beam b/bootstrap/lib/stdlib/ebin/shell.beam
index 31437e38e1..4df0c4f888 100644
--- a/bootstrap/lib/stdlib/ebin/shell.beam
+++ b/bootstrap/lib/stdlib/ebin/shell.beam
diff --git a/bootstrap/lib/stdlib/ebin/slave.beam b/bootstrap/lib/stdlib/ebin/slave.beam
index c5c7d79bbc..0cbd0067c0 100644
--- a/bootstrap/lib/stdlib/ebin/slave.beam
+++ b/bootstrap/lib/stdlib/ebin/slave.beam
diff --git a/bootstrap/lib/stdlib/ebin/sofs.beam b/bootstrap/lib/stdlib/ebin/sofs.beam
index 4045afa010..9f909e608b 100644
--- a/bootstrap/lib/stdlib/ebin/sofs.beam
+++ b/bootstrap/lib/stdlib/ebin/sofs.beam
diff --git a/bootstrap/lib/stdlib/ebin/stdlib.app b/bootstrap/lib/stdlib/ebin/stdlib.app
index 4f3f8e759f..a8abad00ea 100644
--- a/bootstrap/lib/stdlib/ebin/stdlib.app
+++ b/bootstrap/lib/stdlib/ebin/stdlib.app
@@ -20,7 +20,7 @@
 %%
 {application, stdlib,
  [{description, "ERTS  CXC 138 10"},
-  {vsn, "3.4.1"},
+  {vsn, "3.4.2"},
   {modules, [array,
 	     base64,
 	     beam_lib,
@@ -101,13 +101,14 @@
 	     timer,
 	     unicode,
              unicode_util,
+	     uri_string,
 	     win32reg,
 	     zip]},
   {registered,[timer_server,rsh_starter,take_over_monitor,pool_master,
                dets]},
   {applications, [kernel]},
   {env, []},
-  {runtime_dependencies, ["sasl-3.0","kernel-5.0","erts-9.0","crypto-3.3",
+  {runtime_dependencies, ["sasl-3.0","kernel-6.0","erts-10.0","crypto-3.3",
 			  "compiler-5.0"]}
 ]}.
 
diff --git a/bootstrap/lib/stdlib/ebin/stdlib.appup b/bootstrap/lib/stdlib/ebin/stdlib.appup
index 63b5f82103..9996bfae81 100644
--- a/bootstrap/lib/stdlib/ebin/stdlib.appup
+++ b/bootstrap/lib/stdlib/ebin/stdlib.appup
@@ -16,9 +16,9 @@
 %% limitations under the License.
 %%
 %% %CopyrightEnd%
-{"3.4.1",
+{"3.4.2",
  %% Up from - max one major revision back
- [{<<"3\\.[0-3](\\.[0-9]+)*">>,[restart_new_emulator]}], % OTP-19.*
+ [{<<"3\\.4(\\.[0-9]+)*">>,[restart_new_emulator]}], % OTP-20.*
  %% Down to - max one major revision back
- [{<<"3\\.[0-3](\\.[0-9]+)*">>,[restart_new_emulator]}]  % OTP-19.*
+ [{<<"3\\.4(\\.[0-9]+)*">>,[restart_new_emulator]}]  % OTP-20.*
 }.
diff --git a/bootstrap/lib/stdlib/ebin/string.beam b/bootstrap/lib/stdlib/ebin/string.beam
index 0292c1dee0..ff5fab297d 100644
--- a/bootstrap/lib/stdlib/ebin/string.beam
+++ b/bootstrap/lib/stdlib/ebin/string.beam
diff --git a/bootstrap/lib/stdlib/ebin/supervisor.beam b/bootstrap/lib/stdlib/ebin/supervisor.beam
index cb8ad2a6b2..66d9248765 100644
--- a/bootstrap/lib/stdlib/ebin/supervisor.beam
+++ b/bootstrap/lib/stdlib/ebin/supervisor.beam
diff --git a/bootstrap/lib/stdlib/ebin/supervisor_bridge.beam b/bootstrap/lib/stdlib/ebin/supervisor_bridge.beam
index 4d913ca680..599e490e4c 100644
--- a/bootstrap/lib/stdlib/ebin/supervisor_bridge.beam
+++ b/bootstrap/lib/stdlib/ebin/supervisor_bridge.beam
diff --git a/bootstrap/lib/stdlib/ebin/sys.beam b/bootstrap/lib/stdlib/ebin/sys.beam
index ce0895e903..9781a563a7 100644
--- a/bootstrap/lib/stdlib/ebin/sys.beam
+++ b/bootstrap/lib/stdlib/ebin/sys.beam
diff --git a/bootstrap/lib/stdlib/ebin/timer.beam b/bootstrap/lib/stdlib/ebin/timer.beam
index 4c570cbee6..7397379a29 100644
--- a/bootstrap/lib/stdlib/ebin/timer.beam
+++ b/bootstrap/lib/stdlib/ebin/timer.beam
diff --git a/bootstrap/lib/stdlib/ebin/unicode.beam b/bootstrap/lib/stdlib/ebin/unicode.beam
index 23fe5d9c46..a59453c666 100644
--- a/bootstrap/lib/stdlib/ebin/unicode.beam
+++ b/bootstrap/lib/stdlib/ebin/unicode.beam
diff --git a/bootstrap/lib/stdlib/ebin/unicode_util.beam b/bootstrap/lib/stdlib/ebin/unicode_util.beam
index 05cc455f9b..511b8aae79 100644
--- a/bootstrap/lib/stdlib/ebin/unicode_util.beam
+++ b/bootstrap/lib/stdlib/ebin/unicode_util.beam
diff --git a/bootstrap/lib/stdlib/ebin/uri_string.beam b/bootstrap/lib/stdlib/ebin/uri_string.beam
new file mode 100644
index 0000000000..fe4033a513
--- /dev/null
+++ b/bootstrap/lib/stdlib/ebin/uri_string.beam
diff --git a/bootstrap/lib/stdlib/ebin/win32reg.beam b/bootstrap/lib/stdlib/ebin/win32reg.beam
index 85a84529e4..416ed15bfd 100644
--- a/bootstrap/lib/stdlib/ebin/win32reg.beam
+++ b/bootstrap/lib/stdlib/ebin/win32reg.beam
diff --git a/bootstrap/lib/stdlib/ebin/zip.beam b/bootstrap/lib/stdlib/ebin/zip.beam
index 7e21ed9f14..ea54e17a17 100644
--- a/bootstrap/lib/stdlib/ebin/zip.beam
+++ b/bootstrap/lib/stdlib/ebin/zip.beam
diff --git a/erts/Makefile b/erts/Makefile
index ffada839a7..60c70b6a2c 100644
--- a/erts/Makefile
+++ b/erts/Makefile
@@ -34,7 +34,7 @@ ERTSDIRS += start_scripts
 endif
 
 .PHONY: all
-all: $(FLAVORS)
+all: smp
 
 .PHONY: docs
 docs:
@@ -44,20 +44,15 @@ docs:
 debug opt lcnt clean:
 	$(V_at)for d in emulator $(ERTSDIRS); do \
 		if test -d $$d; then \
-			( cd $$d && $(MAKE) $@ FLAVOR=$(FLAVOR) ) || exit $$? ; \
+			( cd $$d && $(MAKE) $@ ) || exit $$?; \
 		fi ; \
 	done
 	(cd preloaded/src && $(MAKE) ../ebin/erts.app)
 
-# ----------------------------------------------------------------------
-# These are "convenience targets", provided as shortcuts for developers
-# - don't use them in scripts or assume they will always stay like this!
-#
-
-.PHONY: $(FLAVORS)
-$(FLAVORS):
+.PHONY: smp
+smp:
 	$(V_at)for type in $(TYPES); do \
-		( $(MAKE) $$type FLAVOR=$@ ); \
+		( $(MAKE) $$type ) || exit $$?; \
 	done
 
 # Make erl script and erlc in $(ERL_TOP)/bin which runs the compiled version
@@ -112,6 +107,11 @@ local_setup:
 		$(ERL_TOP)/bin/start_clean.script \
 		$(ERL_TOP)/bin/no_dot_erlang.script
 
+# ----------------------------------------------------------------------
+# These are "convenience targets", provided as shortcuts for developers
+# - don't use them in scripts or assume they will always stay like this!
+#
+
 # Run the configure script
 .PHONY: configure
 configure:
@@ -129,10 +129,8 @@ makefiles:
 
 .PHONY: release
 release:
-	$(V_at)for f in $(FLAVORS); do \
-		for t in $(TYPES); do \
-		  ( cd emulator && $(MAKE) release FLAVOR=$$f TYPE=$$t ) \
-		done \
+	for t in $(TYPES); do \
+	  ( cd emulator && $(MAKE) release TYPE=$$t ) || exit $$?; \
 	done
 	$(V_at)for d in $(ERTSDIRS) $(XINSTDIRS); do \
 		if test -d $$d; then \
diff --git a/erts/aclocal.m4 b/erts/aclocal.m4
index 80bf236188..887babc13f 100644
--- a/erts/aclocal.m4
+++ b/erts/aclocal.m4
@@ -2726,6 +2726,21 @@ AC_DEFUN([LM_TRY_ENABLE_CFLAG], [
     fi
 ])
 
+AC_DEFUN([LM_CHECK_ENABLE_CFLAG], [
+    AC_MSG_CHECKING([whether $CC accepts $1...])
+    saved_CFLAGS=$CFLAGS;
+    CFLAGS="$1 $CFLAGS";
+    AC_TRY_COMPILE([],[return 0;],can_enable_flag=true,can_enable_flag=false)
+    CFLAGS=$saved_CFLAGS;
+    if test "X$can_enable_flag" = "Xtrue"; then
+        AS_VAR_SET($2, true)
+        AC_MSG_RESULT([yes])
+    else
+        AS_VAR_SET($2, false)
+        AC_MSG_RESULT([no])
+    fi
+])
+
 dnl ERL_TRY_LINK_JAVA(CLASSES, FUNCTION-BODY
 dnl                   [ACTION_IF_FOUND [, ACTION-IF-NOT-FOUND]])
 dnl Freely inspired by AC_TRY_LINK. (Maybe better to create a 
diff --git a/erts/configure.in b/erts/configure.in
index 913315e402..2f6043ee85 100644
--- a/erts/configure.in
+++ b/erts/configure.in
@@ -113,32 +113,14 @@ AS_HELP_STRING([--enable-bootstrap-only],
 	# Disable stuff not necessary in a bootstrap only system in order
 	# to speed up things by reducing the amount of stuff needing to be
 	# built...
-	enable_threads=no
-	enable_smp_support=no
 	with_termcap=no
 	with_ssl=no
 	with_ssl_zlib=no
 	enable_hipe=no
 	enable_sctp=no
-        enable_dirty_schedulers=no
-  fi	
+  fi
 ])
 
-AC_ARG_ENABLE(threads,
-AS_HELP_STRING([--enable-threads], [enable async thread support])
-AS_HELP_STRING([--disable-threads], [disable async thread support]),
-[ case "$enableval" in
-    no) enable_threads=no ;;
-    *)  enable_threads=yes ;;
-  esac ], enable_threads=unknown)
-
-AC_ARG_ENABLE(dirty-schedulers,
-AS_HELP_STRING([--enable-dirty-schedulers], [enable dirty scheduler support]),
-[ case "$enableval" in
-    no) enable_dirty_schedulers=no ;;
-    *)  enable_dirty_schedulers=yes ;;
-  esac ], enable_dirty_schedulers=default)
-
 AC_ARG_ENABLE(dirty-schedulers-test,
 AS_HELP_STRING([--enable-dirty-schedulers-test], [enable dirty scheduler test (for debugging purposes)]),
 [ case "$enableval" in
@@ -146,22 +128,6 @@ AS_HELP_STRING([--enable-dirty-schedulers-test], [enable dirty scheduler test (f
     *) enable_dirty_schedulers_test=no ;;
   esac ], enable_dirty_schedulers_test=no)
 
-AC_ARG_ENABLE(smp-support,
-AS_HELP_STRING([--enable-smp-support], [enable smp support])
-AS_HELP_STRING([--disable-smp-support], [disable smp support]),
-[ case "$enableval" in
-    no) enable_smp_support=no ;;
-    *)  enable_smp_support=yes ;;
-  esac ], enable_smp_support=unknown)
-
-AC_ARG_ENABLE(plain-emulator,
-AS_HELP_STRING([--enable-plain-emulator], [enable plain emulator])
-AS_HELP_STRING([--disable-plain-emulator], [disable plain emulator]),
-[ case "$enableval" in
-    no) enable_plain_emulator=no ;;
-    *)  enable_plain_emulator=yes ;;
-  esac ], enable_plain_emulator=unknown)
-
 AC_ARG_ENABLE(smp-require-native-atomics,
 	      AS_HELP_STRING([--disable-smp-require-native-atomics],
                              [disable the SMP requirement of a native atomic implementation]),
@@ -580,6 +546,90 @@ AC_SUBST(WFLAGS)
 AC_SUBST(WERRORFLAGS)
 AC_SUBST(CFLAG_RUNTIME_LIBRARY_PATH)
 
+## Check if we can do profile guided optimization of beam_emu
+LM_CHECK_ENABLE_CFLAG([-fprofile-generate -Werror],[PROFILE_GENERATE])
+LM_CHECK_ENABLE_CFLAG([-fprofile-use -Werror],[PROFILE_USE])
+
+## Check if this is clang
+LM_CHECK_ENABLE_CFLAG([-fprofile-instr-generate -Werror],[PROFILE_INSTR_GENERATE])
+if test "X$PROFILE_INSTR_GENERATE" = "Xtrue"; then
+   # It was clang, now we also have to check if we have llvm-profdata and that
+   # we can link programs with -fprofile-instr-use
+   saved_CFLAGS=$CFLAGS;
+   CFLAGS="-fprofile-instr-generate -Werror $saved_CFLAGS"
+   AC_RUN_IFELSE([AC_LANG_PROGRAM([],[])],
+     [AC_CHECK_PROGS([LLVM_PROFDATA], [llvm-profdata])
+      AC_CHECK_PROGS([XCRUN], [xcrun])
+      if test "X$XCRUN" != "X" -a "X$LLVM_PROFDATA" = "X"; then
+        AC_MSG_CHECKING([for $XCRUN llvm-profdata])
+        if $XCRUN llvm-profdata --help 2>& AS_MESSAGE_LOG_FD >& AS_MESSAGE_LOG_FD; then
+          LLVM_PROFDATA="$XCRUN llvm-profdata"
+          AC_MSG_RESULT([yes])
+        else
+          AC_MSG_RESULT([no])
+        fi
+      fi
+      AC_SUBST(LLVM_PROFDATA)
+      if test "X$LLVM_PROFDATA" != "X"; then
+        CFLAGS="-fprofile-instr-use=default.profdata -Werror $saved_CFLAGS";
+        $LLVM_PROFDATA merge -output=default.profdata *.profraw;
+        AC_MSG_CHECKING([whether gcc accepts -fprofile-instr-use=default.profdata -Werror])
+        AC_COMPILE_IFELSE([],
+          [AC_MSG_RESULT([yes])
+           PROFILE_INSTR_USE=true],
+          [AC_MSG_RESULT([no])
+           PROFILE_INSTR_USE=false])
+        rm -f default.profdata
+      fi],
+     [])
+   rm -f *.profraw
+   CFLAGS=$saved_CFLAGS;
+fi
+
+AC_ARG_ENABLE(pgo,
+AS_HELP_STRING([--enable-pgo],
+               [build erts using PGO (profile guided optimization)]),
+[ case "$enableval" in
+    no) enable_pgo=no ;;
+    *)	enable_pgo=yes ;;
+  esac
+],enable_pgo=default)
+
+LM_CHECK_ENABLE_CFLAG([-fprofile-use -fprofile-correction -Werror],[PROFILE_CORRECTION])
+
+USE_PGO=false
+AC_MSG_CHECKING([whether to do PGO of erts])
+if test $enable_pgo = no; then
+  AC_MSG_RESULT([no, disabled by user])
+elif test $CROSS_COMPILING = yes; then
+  if $enable_pgo = yes; then
+    AC_MSG_ERROR(cannot use PGO when cross-compiling)
+  else
+    AC_MSG_RESULT([no, cross compiling])
+  fi
+elif test "X$host" = "Xwin32"; then
+  AC_MSG_RESULT([no, not supported in windows])
+elif test "X$PROFILE_GENERATE" = "Xtrue" -a "X$PROFILE_USE" = "Xtrue" -a "X$PROFILE_CORRECTION" = "Xtrue"; then
+  ## We need -fprofile-generate and -fprofile-correction support to use PGO with
+  ## gcc as multiple threads run within the executed object files
+  USE_PGO=true
+  PROFILE_COMPILER=gcc
+  AC_MSG_RESULT([yes, using -fprofile-generate -fprofile-correction])
+elif test "X$PROFILE_INSTR_GENERATE" = "Xtrue" -a "X$PROFILE_INSTR_USE" = "Xtrue"; then
+  USE_PGO=true
+  PROFILE_COMPILER=clang
+  AC_MSG_RESULT([yes, using -fprofile-instr-generate])
+else
+  if $enable_pgo = yes; then
+    AC_MSG_ERROR(cannot use PGO with this compiler)
+  else
+    AC_MSG_RESULT([no])
+  fi
+fi
+
+AC_SUBST(USE_PGO)
+AC_SUBST(PROFILE_COMPILER)
+
 AC_CHECK_SIZEOF(void *) # Needed for ARCH and smp checks below
 if test "x$ac_cv_sizeof_void_p" = x8; then
   AC_SUBST(EXTERNAL_WORD_SIZE, 64)
@@ -640,6 +690,7 @@ case $chk_arch_ in
     armv7l)	ARCH=arm;;
     armv7hl)	ARCH=arm;;
     tile)	ARCH=tile;;
+    e2k)       ARCH=e2k;;
     *)	 	ARCH=noarch;;
 esac
 
@@ -996,81 +1047,12 @@ dnl are set by ERL_FIND_ETHR_LIB
 ERL_FIND_ETHR_LIB
 
 if test "X$ETHR_LIB_NAME" = "X"; then
-    found_threads=no
-else
-    found_threads=yes
+   AC_MSG_ERROR([cannot build emulator since no thread library was found])
 fi
 
-FLAVORS=
 TYPES=opt
-ERTS_BUILD_SMP_EMU=$enable_smp_support
-AC_MSG_CHECKING(whether an emulator with smp support should be built)
-case $ERTS_BUILD_SMP_EMU in
-    yes)
-	AC_MSG_RESULT(yes; enabled by user)
-	;;
-    no)
-	AC_MSG_RESULT(no; disabled by user)
-	;;
-    unknown)
-	AC_TRY_COMPILE([],[
-			#if __GNUC__ >= 3 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95)
-			;
-			#else
-			#error old or no gcc
-			#endif
-			],
-			gcc_smp=okgcc,
-			gcc_smp=oldornogcc)
-	ERTS_BUILD_SMP_EMU=yes
-	case "$enable_threads-$gcc_smp-$found_threads-$host_os" in
-
-	    no-*)
-		AC_MSG_RESULT(no; threads disabled by user)
-		ERTS_BUILD_SMP_EMU=no
-		;;
-
-	    *-okgcc-yes-*)
-		AC_MSG_RESULT(yes)
-		ERTS_BUILD_SMP_EMU=yes
-		;;
-
-	    *-win32)
-		AC_MSG_RESULT(yes)
-		ERTS_BUILD_SMP_EMU=yes
-		;;
-
-	    *-oldornogcc-*)
-		AC_MSG_RESULT(no; old gcc or no gcc found)
-		ERTS_BUILD_SMP_EMU=no
-		;;
-
-	    *)
-		AC_MSG_RESULT(no)
-		ERTS_BUILD_SMP_EMU=no
-		;;
-	esac
-	;;
-esac
-
-AC_MSG_CHECKING(whether dirty schedulers should be enabled)
-case $ERTS_BUILD_SMP_EMU-$enable_dirty_schedulers in
-     yes-yes)
-	DIRTY_SCHEDULER_SUPPORT=yes;;
-     yes-default)
-	DIRTY_SCHEDULER_SUPPORT=yes;;
-     no-default)
-	DIRTY_SCHEDULER_SUPPORT=no;;
-     no-yes)
-	AC_MSG_ERROR([No smp emulator will be built, but dirty schedulers requested]);;
-     *)
-	DIRTY_SCHEDULER_SUPPORT=no;;
-esac
-AC_MSG_RESULT($DIRTY_SCHEDULER_SUPPORT)
-AC_SUBST(DIRTY_SCHEDULER_SUPPORT)
 
 DIRTY_SCHEDULER_TEST=$enable_dirty_schedulers_test
-test $DIRTY_SCHEDULER_SUPPORT = yes || DIRTY_SCHEDULER_TEST=no
 AC_SUBST(DIRTY_SCHEDULER_TEST)
 test $DIRTY_SCHEDULER_TEST != yes || {
     test -f "$ERL_TOP/erts/CONF_INFO" || echo "" > "$ERL_TOP/erts/CONF_INFO"
@@ -1085,26 +1067,15 @@ test $DIRTY_SCHEDULER_TEST != yes || {
 EOF
 }
 
-if test $ERTS_BUILD_SMP_EMU = yes; then
+test "X$smp_require_native_atomics" = "Xyes" &&
+     AC_DEFINE(ETHR_SMP_REQUIRE_NATIVE_IMPLS, 1, [Define if you want to enable check for native ethread implementations])
 
-        DEFAULT_FLAVOR=smp
-        FLAVORS="$FLAVORS smp"
-
-	if test $found_threads = no; then
-	    AC_MSG_ERROR([cannot build smp enabled emulator since no thread library was found])
-	fi
-
-	AC_DEFINE(ERTS_HAVE_SMP_EMU, 1, [Define if the smp emulator is built])
-
-	test "X$smp_require_native_atomics" = "Xyes" &&
-	     AC_DEFINE(ETHR_SMP_REQUIRE_NATIVE_IMPLS, 1, [Define if you want to enable check for native ethread implementations])
-
-	case "$ethr_have_native_atomics-$smp_require_native_atomics-$ethr_have_native_spinlock" in
-	  yes-*)
-		if test "$ethr_native_atomic_implementation" = "gcc_sync"; then
-		    test -f "$ERL_TOP/erts/CONF_INFO" ||
-			echo "" > "$ERL_TOP/erts/CONF_INFO"
-		    cat >> $ERL_TOP/erts/CONF_INFO <<EOF
+case "$ethr_have_native_atomics-$smp_require_native_atomics-$ethr_have_native_spinlock" in
+  yes-*)
+	if test "$ethr_native_atomic_implementation" = "gcc_sync"; then
+	    test -f "$ERL_TOP/erts/CONF_INFO" ||
+		echo "" > "$ERL_TOP/erts/CONF_INFO"
+	    cat >> $ERL_TOP/erts/CONF_INFO <<EOF
 
                  WARNING:
                    Only gcc's __sync_* builtins available for
@@ -1121,18 +1092,18 @@ if test $ERTS_BUILD_SMP_EMU = yes; then
                    more information.
 
 EOF
-		fi
-		;;
+	fi
+	;;
 
-	  no-yes-*)
-		AC_MSG_ERROR([No native atomic implementation found. See the \"Atomic Memory Operations and the VM\" chapter of \$ERL_TOP/HOWTO/INSTALL.md for more information.])
-		;;
+  no-yes-*)
+	AC_MSG_ERROR([No native atomic implementation found. See the \"Atomic Memory Operations and the VM\" chapter of \$ERL_TOP/HOWTO/INSTALL.md for more information.])
+	;;
 
-	  no-no-yes)
+  no-no-yes)
 
-		test -f "$ERL_TOP/erts/CONF_INFO" ||
-		    echo "" > "$ERL_TOP/erts/CONF_INFO"
-		cat >> $ERL_TOP/erts/CONF_INFO <<EOF
+	test -f "$ERL_TOP/erts/CONF_INFO" ||
+	    echo "" > "$ERL_TOP/erts/CONF_INFO"
+	cat >> $ERL_TOP/erts/CONF_INFO <<EOF
 
                  No native atomic implementation available.
                  Fallbacks implemented using spinlocks will be
@@ -1141,13 +1112,12 @@ EOF
 		 this.
 
 EOF
-		;;
-
-	  no-no-no)
+	;;
 
-		test -f "$ERL_TOP/erts/CONF_INFO" ||
-		    echo "" > "$ERL_TOP/erts/CONF_INFO"
-		cat >> "$ERL_TOP/erts/CONF_INFO" <<EOF
+  no-no-no)
+	test -f "$ERL_TOP/erts/CONF_INFO" ||
+	    echo "" > "$ERL_TOP/erts/CONF_INFO"
+	cat >> "$ERL_TOP/erts/CONF_INFO" <<EOF
 
                  No native atomic implementation, nor no native
                  spinlock implementation available. Fallbacks
@@ -1156,76 +1126,11 @@ EOF
                  will suffer immensely due to this.
 
 EOF
-		;;
-
-	esac
-
-	enable_threads=force
-fi
-
-AC_SUBST(ERTS_BUILD_SMP_EMU)
-
-ERTS_BUILD_PLAIN_EMU=$enable_plain_emulator
-AC_MSG_CHECKING(whether an emulator without smp support should be built)
-case $ERTS_BUILD_PLAIN_EMU in
-    yes)
-	AC_MSG_RESULT(yes; enabled by user)
-	;;
-    no)
-	AC_MSG_RESULT(no; disabled by user)
 	;;
-    unknown)
-        case "$enable_threads-$ERTS_BUILD_SMP_EMU" in
-            no-*)
-                ERTS_BUILD_PLAIN_EMU=yes
-                AC_MSG_RESULT(yes)
-                ;;
-            *-no)
-                ERTS_BUILD_PLAIN_EMU=yes
-                AC_MSG_RESULT(yes; enabled as smp emulator was disabled)
-                ;;
-            *)
-                ERTS_BUILD_PLAIN_EMU=no
-                AC_MSG_RESULT(no)
-                ;;
-        esac
-        ;;
-esac
-
-case $ERTS_BUILD_PLAIN_EMU in
-     yes)
-     	AC_DEFINE(ERTS_HAVE_PLAIN_EMU, 1, [Define if the non-smp emulator is built])
-        FLAVORS="$FLAVORS plain"
-        test -f "$ERL_TOP/erts/CONF_INFO" || echo "" > "$ERL_TOP/erts/CONF_INFO"
-        cat >> $ERL_TOP/erts/CONF_INFO <<EOF
 
-            The PLAIN aka NON-SMP emulator has been enabled.
-            This is a DEPRECATED feature scheduled for removal
-            in a future major release.
-
-EOF
-        ;;
-     no)
-        ;;
 esac
-
-AC_SUBST(ERTS_BUILD_PLAIN_EMU)
-AC_SUBST(FLAVORS)
 AC_SUBST(TYPES)
 
-case "$ERTS_BUILD_PLAIN_EMU-$ERTS_BUILD_SMP_EMU" in
-     no-no)
-          AC_MSG_ERROR([both smp and non-smp emulators have been disabled, one of them has to be enabled])
-          ;;
-     *-no)
-          DEFAULT_FLAVOR=plain
-          ;;
-        *)
-          ;;
-esac
-
-AC_SUBST(DEFAULT_FLAVOR)
-
 AC_CHECK_FUNCS([posix_fadvise closefrom])
 AC_CHECK_HEADERS([linux/falloc.h])
 dnl * Old glibcs have broken fallocate64(). Make sure not to use it.
@@ -1285,121 +1190,65 @@ if test $i_cv_posix_fallocate_works = yes; then
 fi
 
 #
-# Figure out if the emulator should use threads. The default is set above
-# in the enable_threads variable. It can have the following values:
-#
-#   no      single-threaded emulator requested
-#   yes     multi-threaded emulator requested
-#   force   multi-threaded emulator required
-#
 # EMU_THR_LIB_NAME, EMU_THR_LIBS, EMU_THR_X_LIBS, and EMU_THR_DEFS is
 # used by the emulator, and can (but should not) be used by applications
 # that only require thread support when the emulator has thread support.
 # Other applications should use ETHR_LIB_NAME, ETHR_LIBS, ETHR_X_LIBS,
 # and ETHR_DEFS.
 #
-AC_MSG_CHECKING(whether the emulator should use threads)
 
 EMU_THR_LIB_NAME=
 EMU_THR_X_LIBS=
 EMU_THR_LIBS=
 EMU_THR_DEFS=
-emu_threads=no
-
-case "$enable_threads"-"$host_os" in
-	*-win32)
-		# The windows erlang emulator can never run without threads.
-		# It has to be enabled or the emulator will crash. Until that
-		# is fixed we force threads on win32.
-		enable_threads=force ;;
-	yes-osf*)
-		# The emulator hang when threads are enabled on osf
-		AC_MSG_ERROR(unresolved problems exist with threads on this platform) ;;
-	*) ;;
-esac
 
-case "$enable_threads"-"$found_threads" in
-    force-yes)
-	emu_threads=yes
-	AC_MSG_RESULT(yes; thread support required and therefore forced) ;;
-    yes-yes)
-	emu_threads=yes
-	AC_MSG_RESULT(yes; enabled by user) ;;
-    unknown-yes)
-	case $host_os in
-	    solaris*|linux*|darwin*|win32)
-		emu_threads=yes
-		AC_MSG_RESULT(yes; default on this platform)
-		;;
-	    *)
-		AC_MSG_RESULT(no; default on this platform)
-		;;
-	esac
-	;;
-    no-yes)
-	AC_MSG_RESULT(no; thread support found but disabled by user) ;;
-    unknown-no|no-no)
-	AC_MSG_RESULT(no) ;;
-    force-no)
-	AC_MSG_ERROR(thread support required but not found) ;;
-    yes-no)
-	AC_MSG_ERROR(thread support enabled by user but not found) ;;
-    *)
-	AC_MSG_ERROR(internal error) ;;
-esac
+# Threads enabled for emulator
+EMU_THR_LIB_NAME=$ETHR_LIB_NAME
+EMU_THR_X_LIBS=$ETHR_X_LIBS
+EMU_THR_LIBS=$ETHR_LIBS
+EMU_THR_DEFS=$ETHR_DEFS
+ENABLE_ALLOC_TYPE_VARS="$ENABLE_ALLOC_TYPE_VARS threads"
+AC_MSG_CHECKING(whether lock checking should be enabled)
+AC_MSG_RESULT($enable_lock_check)
+if test "x$enable_lock_check" != "xno"; then
+    EMU_THR_DEFS="$EMU_THR_DEFS -DERTS_ENABLE_LOCK_CHECK"
+fi
 
-if test $emu_threads != yes; then
-	enable_lock_check=no
-	enable_lock_count=no
-else
-	# Threads enabled for emulator
-	EMU_THR_LIB_NAME=$ETHR_LIB_NAME
-	EMU_THR_X_LIBS=$ETHR_X_LIBS
-	EMU_THR_LIBS=$ETHR_LIBS
-	EMU_THR_DEFS=$ETHR_DEFS
-	ENABLE_ALLOC_TYPE_VARS="$ENABLE_ALLOC_TYPE_VARS threads"
-	AC_MSG_CHECKING(whether lock checking should be enabled)
-	AC_MSG_RESULT($enable_lock_check)
-	if test "x$enable_lock_check" != "xno"; then
-	    EMU_THR_DEFS="$EMU_THR_DEFS -DERTS_ENABLE_LOCK_CHECK"
-	fi
+AC_MSG_CHECKING(whether lock counters should be enabled)
+AC_MSG_RESULT($enable_lock_count)
+if test "x$enable_lock_count" != "xno"; then
+    TYPES="$TYPES lcnt"
+fi
 
-	AC_MSG_CHECKING(whether lock counters should be enabled)
-	AC_MSG_RESULT($enable_lock_count)
-	if test "x$enable_lock_count" != "xno"; then
-	    TYPES="$TYPES lcnt"
+case $host_os in
+    linux*)
+	AC_MSG_CHECKING([whether dlopen() needs to be called before first call to dlerror()])
+	if test "x$ETHR_THR_LIB_BASE_TYPE" != "xposix_nptl"; then
+	    AC_DEFINE(ERTS_NEED_DLOPEN_BEFORE_DLERROR,[1],
+		[Define if dlopen() needs to be called before first call to dlerror()])
+		AC_MSG_RESULT(yes)
+	else
+		AC_MSG_RESULT(no)
 	fi
+	;;
+    *)
+	;;
+esac
 
-	case $host_os in
-	    linux*)
-		AC_MSG_CHECKING([whether dlopen() needs to be called before first call to dlerror()])
-		if test "x$ETHR_THR_LIB_BASE_TYPE" != "xposix_nptl"; then
-		    AC_DEFINE(ERTS_NEED_DLOPEN_BEFORE_DLERROR,[1],
-			[Define if dlopen() needs to be called before first call to dlerror()])
-			AC_MSG_RESULT(yes)
-		else
-			AC_MSG_RESULT(no)
-		fi
-		;;
-	    *)
-		;;
-	esac
-
-	# Remove -D_WIN32_WINNT*, -DWINVER* and -D_GNU_SOURCE from EMU_THR_DEFS
-	# (defined in CFLAGS). Note that we want to keep these flags
-	# in ETHR_DEFS, but not in EMU_THR_DEFS.
-	new_emu_thr_defs=
-	for thr_def in $EMU_THR_DEFS; do
-	    case $thr_def in
-		-D_GNU_SOURCE*|-D_WIN32_WINNT*|-DWINVER*)
-		    ;;
-		*)
-		    new_emu_thr_defs="$new_emu_thr_defs $thr_def"
-		    ;;
-	    esac
-	done
-	EMU_THR_DEFS=$new_emu_thr_defs
-fi
+# Remove -D_WIN32_WINNT*, -DWINVER* and -D_GNU_SOURCE from EMU_THR_DEFS
+# (defined in CFLAGS). Note that we want to keep these flags
+# in ETHR_DEFS, but not in EMU_THR_DEFS.
+new_emu_thr_defs=
+for thr_def in $EMU_THR_DEFS; do
+    case $thr_def in
+	-D_GNU_SOURCE*|-D_WIN32_WINNT*|-DWINVER*)
+	    ;;
+	*)
+	    new_emu_thr_defs="$new_emu_thr_defs $thr_def"
+	    ;;
+    esac
+done
+EMU_THR_DEFS=$new_emu_thr_defs
 
 AC_SUBST(EMU_THR_LIB_NAME)
 AC_SUBST(EMU_THR_X_LIBS)
@@ -2451,9 +2300,6 @@ extern char end;
 #elif defined(HAVE__END_SYMBOL)
 extern char _end;
 #endif
-#ifndef USE_THREADS
-#undef ETHR_PTHREADS
-#endif
 
 #ifdef ETHR_PTHREADS
 #  ifdef ETHR_HAVE_PTHREAD_H
@@ -2687,10 +2533,6 @@ extern char _end;
 #  error no 'end' nor '_end'
 #endif
 
-#ifndef USE_THREADS
-#undef ETHR_PTHREADS
-#endif
-
 #ifdef ETHR_PTHREADS
 #  ifdef ETHR_HAVE_PTHREAD_H
 #    include <pthread.h>
@@ -2920,6 +2762,20 @@ if test X${enable_hipe} = Xyes && test X$ARCH = Xamd64; then
 			     LDFLAGS=$saved_LDFLAGS])])])
 fi
 
+if test X${enable_hipe} = Xyes; then
+   case $OPSYS in
+	linux)
+		ppcBEAMLDFLAGS="-Wl,-m,elf32ppc"
+		ppc64BEAMLDFLAGS="-Wl,-m,elf64ppc,-T,hipe/elf64ppc.x"
+		;;
+	darwin)
+		amd64BEAMLDFLAGS="-pagezero_size 0x10000000"
+		;;
+   esac
+   archVarName="${ARCH}BEAMLDFLAGS"
+   eval HIPEBEAMLDFLAGS=\$$archVarName
+fi
+AC_SUBST(HIPEBEAMLDFLAGS)
 
 if test X${enable_fp_exceptions} = Xauto ; then
    case $host_os in
@@ -3483,10 +3339,7 @@ esac
     fi
 fi	
 
-	
-	 
-		
-
+AC_SUBST(FPE)
 
 
 dnl
@@ -3620,62 +3473,24 @@ case $poll_works-$host_os in
 esac
 
 #
-# If kqueue() found, check that it can be selected or polled on...
+# If kqueue() found
 #
 if test $have_kernel_poll = kqueue; then
-	if test $poll_works = yes; then
-		kqueue_with=poll
-	else
-		kqueue_with=select
-	fi
-	AC_MSG_CHECKING([whether kqueue() fd can be ${kqueue_with}()ed on])
-	AC_TRY_RUN([
-#include <stdlib.h>
-#include <sys/types.h>
-#include <sys/event.h>
-#include <sys/time.h>
-#ifdef ERTS_USE_POLL
-#include <poll.h>
-#else
-#include <unistd.h>
-#endif
-int main(void) {
-    int kq = kqueue();
-    if (kq < 0) return 2;
-    {
-#ifdef ERTS_USE_POLL
-	struct pollfd pfds = {kq, POLLIN, 0};
-	if (poll(&pfds, 1, 0) < 0) return 1;
-#else
-	struct timeval tv = {0, 0};
-	fd_set set; FD_ZERO(&set); FD_SET(kq, &set);
-	if (select(kq+1, &set, NULL, NULL, &tv) < 0) return 1;
-#endif
-    }
-    return 0;
-}
-	],
-	ok_kqueue=yes,
-	ok_kqueue=no,
-	[
-	case X$erl_xcomp_kqueue in
-	    X) ok_kqueue=cross;;
-	    Xyes|Xno) ok_kqueue=$erl_xcomp_kqueue;;
-	    *) AC_MSG_ERROR([Bad erl_xcomp_kqueue value: $erl_xcomp_kqueue]);;
-	esac
-	])
-	AC_MSG_RESULT($ok_kqueue);
-	case $ok_kqueue in
-	    yes)
-		;;
-	    cross)
-		have_kernel_poll=no
-		AC_MSG_WARN([result no guessed because of cross compilation]);;
-	    *)
-		have_kernel_poll=no;;
-	esac
+## Some OS X kernel version seems to have bugs in them with regards to kqueue
+## Disable kernel poll on those versions
+   AC_MSG_CHECKING([whether host os has known kqueue bugs])
+   case $host_os in
+     # Any OS X version < 16 has known problems with using kqueue
+     # so we don't use it there. See erl_poll.c for details.
+     darwin[[0-9]].*|darwin1[[0-5]].*)
+        AC_MSG_RESULT([yes, disabling kernel poll])
+        have_kernel_poll=no
+        ;;
+     *)
+        AC_MSG_RESULT([no])
+        ;;
+   esac
 fi
-
 #
 # If epoll() found, check that it is level triggered.
 #
@@ -3702,6 +3517,7 @@ fi
 #
 AC_MSG_CHECKING(whether kernel poll support should be enabled)
 ERTS_ENABLE_KERNEL_POLL=no
+ERTS_BUILD_FALLBACK_POLL=no
 case $enable_kernel_poll-$have_kernel_poll in
     no-*)
 	AC_MSG_RESULT(no; disabled by user);;
@@ -3712,11 +3528,16 @@ case $enable_kernel_poll-$have_kernel_poll in
     *)
 	case $have_kernel_poll in
 	    epoll)
-		AC_DEFINE(HAVE_SYS_EPOLL_H, 1, [Define if you have the <sys/epoll.h> header file.]);;
+		AC_DEFINE(HAVE_SYS_EPOLL_H, 1, [Define if you have the <sys/epoll.h> header file.])
+                ERTS_BUILD_FALLBACK_POLL=yes
+                ;;
 	    /dev/poll)
-		AC_DEFINE(HAVE_SYS_DEVPOLL_H, 1, [Define if you have <sys/devpoll.h> header file.]);;
+		AC_DEFINE(HAVE_SYS_DEVPOLL_H, 1, [Define if you have <sys/devpoll.h> header file.])
+                ;;
 	    kqueue)
-		AC_DEFINE(HAVE_SYS_EVENT_H, 1, [Define if you have <sys/event.h> header file.]);;
+		AC_DEFINE(HAVE_SYS_EVENT_H, 1, [Define if you have <sys/event.h> header file.])
+                ERTS_BUILD_FALLBACK_POLL=yes
+                ;;
 	    *)
 		AC_MSG_ERROR(configure.in need to be updated);;
 	esac
@@ -3724,7 +3545,7 @@ case $enable_kernel_poll-$have_kernel_poll in
 	AC_DEFINE(ERTS_ENABLE_KERNEL_POLL, 1, [Define if you have kernel poll and want to use it])
 	AC_MSG_RESULT([yes; $have_kernel_poll]);;
 esac
-AC_SUBST(ERTS_ENABLE_KERNEL_POLL)
+AC_SUBST(ERTS_BUILD_FALLBACK_POLL)
 
 AC_MSG_CHECKING([whether putenv() stores a copy of the key-value pair])
 AC_TRY_RUN([
@@ -3949,6 +3770,39 @@ dnl
 LM_FIND_EMU_CC
 
 dnl
+dnl Test whether code pointers are always short (32 bits).
+dnl
+
+AC_MSG_CHECKING([whether the code model is small])
+saved_LDFLAGS="$LDFLAGS"
+LDFLAGS="$LDFLAGS $HIPEBEAMLDFLAGS"
+AC_TRY_RUN([
+   #include <stdlib.h>
+   int main() {
+    if ((unsigned long long)&main < (1ull << 32)) {
+       exit(0);
+    }
+    exit(1);
+   }
+],
+erl_code_model_small=yes,
+erl_code_model_small=no,
+erl_code_model_small=no)
+AC_MSG_RESULT([$erl_code_model_small])
+LDFLAGS="$saved_LDFLAGS"
+case $erl_code_model_small in
+     yes)
+        AC_DEFINE(CODE_MODEL_SMALL,[1],
+	[Define if the code model is small (code fits below 2Gb)])
+	CODE_MODEL=small
+	;;
+     no)
+	CODE_MODEL=unknown
+        ;;
+esac
+AC_SUBST(CODE_MODEL)
+
+dnl
 dnl DTrace & LTTNG
 dnl
 case $DYNAMIC_TRACE_FRAMEWORK in
@@ -4982,7 +4836,7 @@ AH_BOTTOM([
 # endif
 #endif
 
-#if defined(DEBUG) && defined(USE_THREADS) && !defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(DEBUG) && !defined(ERTS_ENABLE_LOCK_CHECK)
 #define ERTS_ENABLE_LOCK_CHECK 1
 #endif
 ])
diff --git a/erts/doc/src/Makefile b/erts/doc/src/Makefile
index 18c5490d7b..c4f1baf89e 100644
--- a/erts/doc/src/Makefile
+++ b/erts/doc/src/Makefile
@@ -171,6 +171,8 @@ release_docs_spec: docs
 		"$(RELSYSDIR)/doc/html"
 	$(INSTALL_DATA) $(ERL_TOP)/erts/example/time_compat.erl \
 		"$(RELSYSDIR)/doc/html"
+	$(INSTALL_DATA) $(ERL_TOP)/lib/kernel/examples/gen_tcp_dist/src/gen_tcp_dist.erl \
+		"$(RELSYSDIR)/doc/html"
 	$(INSTALL_DATA) $(INFO_FILE) "$(RELSYSDIR)"
 	$(INSTALL_DIR) "$(RELEASE_PATH)/man/man3"
 	$(INSTALL_DATA) $(MAN3DIR)/* "$(RELEASE_PATH)/man/man3"
diff --git a/erts/doc/src/alt_dist.xml b/erts/doc/src/alt_dist.xml
index be969a8267..d3731a5391 100644
--- a/erts/doc/src/alt_dist.xml
+++ b/erts/doc/src/alt_dist.xml
@@ -47,23 +47,30 @@
     runs on. The reason the C code is not made portable, is simply
     readability.</p>
 
-  <note>
-    <p>This section was written a long time ago. Most of it is still
-      valid, but some things have changed since then.
-      Most notably is the driver interface. Some updates have been made
-      to the documentation of the driver presented here,
-      but more can be done and is planned for the future.
-      The reader is encouraged to read the
-      <seealso marker="erl_driver"><c>erl_driver</c></seealso> and
-      <seealso marker="driver_entry"><c>driver_entry</c></seealso>
-      documentation also.</p>
-  </note>
-
   <section>
     <title>Introduction</title>
     <p>To implement a new carrier for the Erlang distribution, the main
       steps are as follows.</p>
 
+      <note><p>
+	As of ERTS version 10.0 support for distribution controller
+	processes has been introduced. That is, the traffic over a
+	distribution channel can be managed by a process instead of
+	only by a port. This makes it possible to implement large
+	parts of the logic in Erlang code, and you perhaps do not
+	even need a new driver for the protocol. One example could
+	be Erlang distribution over UDP using <c>gen_udp</c> (your
+	Erlang code will of course have to take care of retranspissions,
+	etc in this example). That is, depending on what you want
+	to do you perhaps do not need to implement a driver at all
+	and can then skip the driver related sections below.
+	The <c>gen_tcp_dist</c> example described in the
+	<seealso marker="#distribution_module">Distribution
+	Module</seealso> section utilize distribution controller
+	processes and can be worth having a look at if you want to
+	use distribution controller processes.
+      </p></note>
+
     <section>
       <title>Writing an Erlang Driver</title>
       <p>First, the protocol must be available to the Erlang machine, which
@@ -152,7 +159,712 @@
   </section>
 
   <section>
+    <marker id="distribution_module"/>
+    <title>Distribution Module</title>
+    <p>
+      The distribution module expose an API that <c>net_kernel</c> call
+      in order to manage connections to other nodes. The module name
+      should have the suffix <c>_dist</c>.
+    </p>
+    <p>
+      The module needs to create some kind of listening entity (process
+      or port) and an acceptor process that accepts incoming connections
+      using the listening entity. For each connection, the module at least
+      needs to create one connection supervisor process, which also is
+      responsible for the handshake when setting up the connection, and
+      a distribution controller (process or port) responsible for
+      transport of data over the connection. The distribution controller
+      and the connection supervisor process should be linked together
+      so both of them are cleaned up when the connection is taken down.
+    </p>
+    <p>
+      Note that there need to be exactly one distribution controller
+      per connection. A process or port can only be distribution
+      controller for one connection. The registration as distribution
+      controller cannot be undone. It will stick until the distribution
+      controller terminates. The distribution controller should not
+      ignore exit signals. It is allowed to trap exits, but it should
+      then voluntarily terminate when an exit signal is received.
+    </p>
+    <p>
+      An example implementation of a distribution module can be found
+      in
+      <url href="gen_tcp_dist.erl">$ERL_TOP/lib/kernel/examples/gen_tcp_dist/src/gen_tcp_dist.erl</url>.
+      It implements the distribution over TCP/IP using the <c>gen_tcp</c>
+      API with distribution controllers implemented by processes. This
+      instead of using port distribution controllers as the ordinary TCP/IP
+      distribution uses.
+    </p>
+
+    <section>
+      <marker id="distribution_module_exported_callback_functions"/>
+      <title>Exported Callback Functions</title>
+
+      <p>
+	The following functions are mandatory:
+      </p>
+      <taglist>
+	<tag><marker id="listen"/><c>listen(Name) -></c><br/>&nbsp;&nbsp;<c>{ok, {Listen, Address, Creation}} | {error, Error} </c></tag>
+	<item>
+	  <p>
+	    <c>listen/1</c> is called once in order to listen for incoming
+	    connection requests. The call is made when the distribution is brought
+	    up. The argument <c>Name</c> is the part of the node name before
+	    the <c>@</c> sign in the full node name. It can be either an atom or a
+	    string.
+	  </p>
+	  <p>
+	    The return value consists of a <c>Listen</c> handle (which is
+	    later passed to the <seealso marker="#accept"><c>accept/1</c></seealso>
+	    callback), <c>Address</c> which is a <c>#net_address{}</c> record
+	    with information about the address for the node (the
+	    <c>#net_address{}</c> record is defined in
+	    <c>kernel/include/net_address.hrl</c>), and <c>Creation</c> which
+	    (currently) is an integer <c>1</c>, <c>2</c>, or <c>3</c>.
+	  </p>
+	  <p>
+	    If <seealso marker="erts:epmd"><c>epmd</c></seealso> is to be used 
+	    for node discovery, you typically want to use the (unfortunately
+	    undocumented) <c>erl_epmd</c> module (part of the <c>kernel</c>
+	    application) in order to register the listen port with <c>epmd</c>
+	    and retrieve <c>Creation</c> to use.
+	  </p>
+	</item>
+
+	<tag><marker id="accept"/><c>accept(Listen) -></c><br/>&nbsp;&nbsp;<c>AcceptorPid</c></tag>
+	<item>
+	  <p>
+	    <c>accept/1</c> should spawn a process that accepts connections. This
+	    process should preferably execute on <c>max</c> priority. The process
+	    identifier of this process should be returned.
+	  </p>
+	  <p>
+	    The <c>Listen</c> argument will be the same as the <c>Listen</c> handle
+	    part of the return value of the
+	    <seealso marker="#listen"><c>listen/1</c></seealso> callback above.
+	    <c>accept/1</c> is called only once when the distribution protocol is
+	    started.
+	  </p>
+	  <p>
+	    The caller of this function is a representative for <c>net_kernel</c>
+	    (this may or may not be the process registered as <c>net_kernel</c>)
+	    and is in this document identified as <c>Kernel</c>.
+	    When a connection has been accepted by the acceptor process, it needs
+	    to inform <c>Kernel</c> about the accepted connection. This is done by
+	    passing a message on the form:
+	  </p>
+	  <code type="none"><![CDATA[Kernel ! {accept, AcceptorPid, DistController, Family, Proto}]]></code>
+	  <p>
+	    <c>DistController</c> is either the process or port identifier
+	    of the distribution controller for the connection. The
+	    distribution controller should be created by the acceptor
+	    processes when a new connection is accepted. Its job is to
+	    dispatch traffic on the connection.
+	  </p>
+	  <c>Kernel</c> responds with one of the following messages:
+	  <taglist>
+	    <tag><c>{Kernel, controller, SupervisorPid}</c></tag>
+	    <item>
+	      <p>
+		The request was accepted and <c>SupervisorPid</c> is the
+		process identifier of the connection supervisor process
+		(which is created in the
+		<seealso marker="#accept_connection"><c>accept_connection/5</c></seealso>
+		callback).
+	      </p>
+	    </item>
+	    <tag><c>{Kernel, unsupported_protocol}</c></tag>
+	    <item>
+	      <p>
+		The request was rejected. This is a fatal error. The acceptor
+		process should terminate.
+	      </p>
+	    </item>
+	  </taglist>
+	  <p>
+	    When an accept sequence has been completed the acceptor process
+	    is expected to continue accepting further requests.
+	  </p>
+	</item>
+
+	<tag><marker id="accept_connection"/><c>accept_connection(AcceptorPid, DistCtrl, MyNode, Allowed, SetupTime) -></c><br/>&nbsp;&nbsp;<c>ConnectionSupervisorPid</c></tag>
+	<item>
+	  <p>
+	    <c>accept_connection/5</c> should spawn a process that will
+	    perform the Erlang distribution handshake for the connection.
+	    If the handshake successfully completes it should continue to
+	    function as a connection supervisor. This process
+	    should preferably execute on <c>max</c> priority.
+	  </p>
+	  <p>The arguments:</p>
+	  <taglist>
+	    <tag><c>AcceptorPid</c></tag>
+	    <item>
+	      <p>
+		Process identifier of the process created by the
+		<seealso marker="#accept"><c>accept/1</c></seealso>
+		callback.
+	      </p>
+	    </item>
+	    <tag><c>DistCtrl</c></tag>
+	    <item>
+	      <p>The identifier of the distribution controller identifier
+	      created by the acceptor process. To be passed along to
+	      <c>dist_util:handshake_other_started(HsData)</c>.
+	      </p>
+	    </item>
+	    <tag><c>MyNode</c></tag>
+	    <item>
+	      <p>
+		Node name of this node. To be passed along to
+	      <c>dist_util:handshake_other_started(HsData)</c>.
+	      </p>
+	    </item>
+	    <tag><c>Allowed</c></tag>
+	    <item>
+	      <p>
+		To be passed along to
+		<c>dist_util:handshake_other_started(HsData)</c>.
+	      </p>
+	    </item>
+	    <tag><c>SetupTime</c></tag>
+	    <item>
+	      <p>
+		Time used for creating a setup timer by a
+		call to <c>dist_util:start_timer(SetupTime)</c>.
+		The timer should be passed along to
+		<c>dist_util:handshake_other_started(HsData)</c>.
+	      </p>
+	    </item>
+	  </taglist>
+	  <p>
+	    The created process should provide callbacks and other
+	    information needed for the handshake in a
+	    <seealso marker="#hs_data_record"><c>#hs_data{}</c></seealso>
+	    record and call <c>dist_util:handshake_other_started(HsData)</c>
+	    with this record.
+	  </p>
+	  <p>
+	    <c>dist_util:handshake_other_started(HsData)</c> will perform
+	    the handshake and if the handshake successfully completes this
+	    process will then continue in a connection supervisor loop
+	    as long as the connection is up.
+	  </p>
+	</item>
+	
+	<tag><marker id="setup"/><c>setup(Node, Type, MyNode, LongOrShortNames, SetupTime) -></c><br/>&nbsp;&nbsp;<c>ConnectionSupervisorPid</c></tag>
+	<item>
+	  <p>
+	    <c>setup/5</c> should spawn a process that connects to
+	    <c>Node</c>. When connection has been established it should
+	    perform the Erlang distribution handshake for the connection.
+	    If the handshake successfully completes it should continue to
+	    function as a connection supervisor. This process
+	    should preferably execute on <c>max</c> priority.
+	  </p>
+	  <p>The arguments:</p>
+	  <taglist>
+	    <tag><c>Node</c></tag>
+	    <item>
+	      <p>
+		Node name of remote node. To be passed along to
+		<c>dist_util:handshake_we_started(HsData)</c>.
+	      </p>
+	    </item>
+	    <tag><c>Type</c></tag>
+	    <item>
+	      <p>
+		Connection type. To be passed along to
+		<c>dist_util:handshake_we_started(HsData)</c>.
+	      </p>
+	    </item>
+	    <tag><c>MyNode</c></tag>
+	    <item>
+	      <p>
+		Node name of this node. To be passed along to
+		<c>dist_util:handshake_we_started(HsData)</c>.
+	      </p>
+	    </item>
+	    <tag><c>LongOrShortNames</c></tag>
+	    <item>
+	      <p>
+		Either the atom <c>longnames</c> or
+		the atom <c>shortnames</c> indicating
+		whether long or short names is used.
+	      </p>
+	    </item>
+	    <tag><c>SetupTime</c></tag>
+	    <item>
+	      <p>
+		Time used for creating a setup timer by a
+		call to <c>dist_util:start_timer(SetupTime)</c>.
+		The timer should be passed along to
+		<c>dist_util:handshake_we_started(HsData)</c>.
+	      </p>
+	    </item>
+	  </taglist>
+	  <p>
+	    The caller of this function is a representative for <c>net_kernel</c>
+	    (this may or may not be the process registered as <c>net_kernel</c>)
+	    and is in this document identified as <c>Kernel</c>. 
+	  </p>
+	  <p>
+	    This function should, besides spawning the connection supervisor,
+	    also create a distribution controller. The distribution
+	    controller is either a process or a port which is responsible
+	    for dispatching traffic.
+	  </p>
+	  <p>
+	    The created process should provide callbacks and other
+	    information needed for the handshake in a
+	    <seealso marker="#hs_data_record"><c>#hs_data{}</c></seealso>
+	    record and call <c>dist_util:handshake_we_started(HsData)</c>
+	    with this record.
+	  </p>
+	  <p>
+	    <c>dist_util:handshake_we_started(HsData)</c> will perform
+	    the handshake and the handshake successfully completes this
+	    process will then continue in a connection supervisor loop
+	    as long as the connection is up.
+	  </p>
+	</item>
+	
+	<tag><marker id="close"/><c>close(Listen) -></c><br/>&nbsp;&nbsp;<c>void()</c></tag>
+	
+	<item><p>
+	  Called in order to close the <c>Listen</c> handle
+	  that originally was passed from the
+	  <seealso marker="#listen"><c>listen/1</c></seealso> callback.
+	</p></item>
+	
+	<tag><marker id="select"/><c>select(NodeName) -></c><br/>&nbsp;&nbsp;<c>boolean()</c></tag>
+	<item>
+	  <p>Return <c>true</c> if the host name part
+	  of the <c>NodeName</c> is valid for use
+	  with this protocol; otherwise, <c>false</c>.
+	  </p>
+	</item>
+	
+      </taglist>
+
+      <p>
+	There are also two optional functions that may be
+	exported:
+      </p>
+      <taglist>
+	<tag><marker id="select"/><c>setopts(Listen, Opts) -></c><br/>&nbsp;&nbsp;<c>ok | {error, Error}</c></tag>
+	<item>
+	  <p>
+	    The argument <c>Listen</c> is the handle originally passed
+	    from the
+	    <seealso marker="#listen"><c>listen/1</c></seealso> callback.
+	    The argument <c>Opts</c> is a list of options to set on future
+	    connections.
+	  </p>
+	</item>
+
+	<tag><marker id="select"/><c>getopts(Listen, Opts) -></c><br/>&nbsp;&nbsp;<c>{ok, OptionValues} | {error, Error}</c></tag>
+	<item>
+	  <p>
+	    The argument <c>Listen</c> is the handle originally passed
+	    from the
+	    <seealso marker="#listen"><c>listen/1</c></seealso> callback.
+	    The argument <c>Opts</c> is a list of options to read for future
+	    connections.
+	  </p>
+	</item>
+      </taglist>
+      
+    </section>
+    <section>
+      <marker id="hs_data_record"/>
+      <title>The #hs_data{} Record</title>
+      <p>
+	The <c>dist_util:handshake_we_started/1</c> and
+	<c>dist_util:handshake_other_started/1</c> functions
+	takes a <c>#hs_data{}</c> record as argument. There
+	are quite a lot of fields in this record that you
+	need to set. The record is defined in
+	<c>kernel/include/dist_util.hrl</c>. Not documented
+	fields should not be set, i.e., should be left as
+	<c>undefined</c>.
+      </p>
+      <p>
+	The following <c>#hs_data{}</c> record fields need
+	to be set unless otherwise stated:</p>
+      <taglist>
+	<tag><marker id="hs_data_kernel_pid"/><c>kernel_pid</c></tag>
+	<item>
+	  <p>
+	    Process identifier of the <c>Kernel</c> process. That is,
+	    the process that called either
+	    <seealso marker="#setup"><c>setup/5</c></seealso> or
+	    <seealso marker="#accept_connection"><c>accept_connection/5</c></seealso>.
+	  </p>
+	</item>
+
+	<tag><marker id="hs_data_other_node"/><c>other_node</c></tag>
+	<item>
+	  <p>Name of the other node. This field is only
+	  mandatory when this node initiates the connection.
+	  That is, when connection is set up via
+	  <seealso marker="#setup"><c>setup/5</c></seealso>.
+	  </p>
+	</item>
+
+	<tag><marker id="hs_data_this_node"/><c>this_node</c></tag>
+	<item>
+	  <p>
+	    The node name of this node.
+	  </p>
+	</item>
+
+	<tag><marker id="hs_data_socket"/><c>socket</c></tag>
+	<item>
+	  <p>
+	    The identifier of the distribution controller.
+	  </p>
+	</item>
+	
+	<tag><marker id="hs_data_timer"/><c>timer</c></tag>
+	<item>
+	  <p>
+	    The timer created using <c>dist_util:start_timer/1</c>.
+	  </p>
+	</item>
+
+	<tag><marker id="hs_data_allowed"/><c>allowed</c></tag>
+	<item>
+	  <p>Information passed as <c>Allowed</c> to
+	  <c>accept_connection/5</c>. This field is only
+	  mandatory when the remote node initiated the
+	  connection. That is, when the connection is set
+	  up via
+	  <seealso marker="#accept_connection"><c>accept_connection/5</c></seealso>.
+	  </p>
+	</item>
+      
+	<tag><marker id="hs_data_f_send"/><c>f_send</c></tag>
+	<item>
+	  <p>
+	    A fun with the following signature:
+	  </p>
+	  <code type="none"><![CDATA[fun (DistCtrlr, Data) -> ok | {error, Error}]]></code>
+	  <p>
+	    where <c>DistCtrlr</c> is the identifier of
+	    the distribution controller and <c>Data</c>
+	    is io data to pass to the other side.
+	  </p>
+	  <p>Only used during handshake phase.</p>
+	</item>
+	
+	<tag><marker id="hs_data_f_recv"/><c>f_recv</c></tag>
+	<item>
+	  <p>
+	    A fun with the following signature:
+	  </p>
+	  <code type="none"><![CDATA[fun (DistCtrlr, Length) -> {ok, Packet} | {error, Reason}]]></code>
+	  <p>
+	    where <c>DistCtrlr</c> is the identifier of the distribution
+	    controller.
+	    If <c>Length</c> is <c>0</c>, all available bytes should be
+	    returned. If <c>Length > 0</c>, exactly <c>Length</c> bytes
+	    should be returned, or an error; possibly discarding less
+	    than <c>Length</c> bytes of data when the connection is
+	    closed from the other side.
+	    It is used for passive receive of data from the
+	    other end.
+	  </p>
+	  <p>Only used during handshake phase.</p>
+	</item>
+
+	<tag><marker id="hs_data_f_setopts_pre_nodeup"/><c>f_setopts_pre_nodeup</c></tag>
+	<item>
+	  <p>
+	    A fun with the following signature:
+	  </p>
+	  <code type="none"><![CDATA[fun (DistCtrlr) -> ok | {error, Error}]]></code>
+	  <p>
+	    where <c>DistCtrlr</c> is the identifier of
+	    the distribution controller. Called just
+	    before the distribution channel is taken up
+	    for normal traffic.
+	  </p>
+	  <p>Only used during handshake phase.</p>
+	</item>
+
+	<tag><marker id="hs_data_f_setopts_post_nodeup"/><c>f_setopts_post_nodeup</c></tag>
+	<item>
+	  <p>
+	    A fun with the following signature:
+	  </p>
+	  <code type="none"><![CDATA[fun (DistCtrlr) -> ok | {error, Error}]]></code>
+	  <p>
+	    where <c>DistCtrlr</c> is the identifier of
+	    the distribution controller. Called just
+	    after distribution channel has been taken
+	    up for normal traffic.
+	  </p>
+	  <p>Only used during handshake phase.</p>
+	</item>
+
+	<tag><marker id="hs_data_f_getll"/><c>f_getll</c></tag>
+	<item>
+	  <p>
+	    A fun with the following signature:
+	  </p>
+	  <code type="none"><![CDATA[fun (DistCtrlr) -> ID]]></code>
+	  <p>
+	    where <c>DistCtrlr</c> is the identifier of
+	    the distribution controller and <c>ID</c> is
+	    the identifier of the low level entity that
+	    handles the connection (often <c>DistCtrlr</c>
+	    itself).
+	  </p>
+	  <p>Only used during handshake phase.</p>
+	</item>
+
+	<tag><marker id="hs_data_f_address"/><c>f_address</c></tag>
+	<item>
+	  <p>
+	    A fun with the following signature:
+	  </p>
+	  <code type="none"><![CDATA[fun (DistCtrlr, Node) -> NetAddress]]></code>
+	  <p>
+	    where <c>DistCtrlr</c> is the identifier of
+	    the distribution controller, <c>Node</c>
+	    is the node name of the node on the other end,
+	    and <c>NetAddress</c> is a <c>#net_address{}</c>
+	    record with information about the address
+	    for the <c>Node</c> on the other end of the
+	    connection. The <c>#net_address{}</c> record
+	    is defined in
+	    <c>kernel/include/net_address.hrl</c>.
+	  </p>
+	  <p>Only used during handshake phase.</p>
+	</item>
+
+	<tag><marker id="hs_data_mf_tick"/><c>mf_tick</c></tag>
+	<item>
+	  <p>
+	    A fun with the following signature:
+	  </p>
+	  <code type="none"><![CDATA[fun (DistCtrlr) -> void()]]></code>
+	  <p>
+	    where <c>DistCtrlr</c> is the identifier
+	    of the distribution controller. This
+	    function should send information over
+	    the connection that is not interpreted
+	    by the other end while increasing the
+	    statistics of received packets on the
+	    other end. This is usually implemented by
+	    sending an empty packet.
+	  </p>
+	  <note><p>
+	    It is of vital importance that this operation
+	    does not block the caller for a long time.
+	    This since it is called from the connection
+	    supervisor.
+	  </p></note>
+	  <p>Used when connection is up.</p>
+	</item>
+
+	<tag><marker id="hs_data_mf_getstat"/><c>mf_getstat</c></tag>
+	<item>
+	  <p>
+	    A fun with the following signature:
+	  </p>
+	  <code type="none"><![CDATA[fun (DistCtrlr) -> {ok, Received, Sent, PendSend}]]></code>
+	  <p>
+	    where <c>DistCtrlr</c> is the identifier
+	    of the distribution controller, <c>Received</c>
+	    is received packets, <c>Sent</c> is
+	    sent packets, and <c>PendSend</c> is
+	    amount of packets in queue to be sent
+	    or a <c>boolean()</c> indicating whether
+	    there are packets in queue to be sent.
+	  </p>
+	  <note><p>
+	    It is of vital importance that this operation
+	    does not block the caller for a long time.
+	    This since it is called from the connection
+	    supervisor.
+	  </p></note>
+	  <p>Used when connection is up.</p>
+	</item>
+
+	<tag><marker id="hs_data_request_type"/><c>request_type</c></tag>
+	<item>
+	  <p>
+	    The request <c>Type</c> as passed to
+	    <seealso marker="#setup"><c>setup/5</c></seealso>.
+	    This is only mandatory when the connection has
+	    been initiated by this node. That is, the connection
+	    is set up via <c>setup/5</c>.
+	  </p>
+	</item>
+
+	<tag><marker id="hs_data_mf_setopts"/><c>mf_setopts</c></tag>
+	<item>
+	  <p>
+	    A fun with the following signature:
+	  </p>
+	  <code type="none"><![CDATA[fun (DistCtrl, Opts) -> ok | {error, Error}]]></code>
+	  <p>
+	    where <c>DistCtrlr</c> is the identifier
+	    of the distribution controller and <c>Opts</c>
+	    is a list of options to set on the connection.
+	  </p>
+	  <p>This function is optional. Used when connection is up.</p>
+	</item>
+	
+	<tag><marker id="hs_data_mf_getopts"/><c>mf_getopts</c></tag>
+	<item>
+	  <p>
+	    A fun with the following signature:
+	  </p>
+	  <code type="none"><![CDATA[fun (DistCtrl, Opts) -> {ok, OptionValues} | {error, Error}]]></code>
+	  <p>
+	    where <c>DistCtrlr</c> is the identifier
+	    of the distribution controller and <c>Opts</c>
+	    is a list of options to read for the connection.
+	  </p>
+	  <p>This function is optional. Used when connection is up.</p>
+	</item>
+
+	<tag><marker id="hs_data_f_handshake_complete"/><c>f_handshake_complete</c></tag>
+	<item>
+	  <p>
+	    A fun with the following signature:
+	  </p>
+	  <code type="none"><![CDATA[fun (DistCtrlr, Node, DHandle) -> void()]]></code>
+	  <p>
+	    where <c>DistCtrlr</c> is the identifier
+	    of the distribution controller, <c>Node</c> is
+	    the node name of the node connected at the other
+	    end, and <c>DHandle</c> is a distribution handle
+	    needed by a distribution controller process when
+	    calling the following BIFs:
+	  </p>
+	  <list>
+	    <item><p><seealso marker="erts:erlang#dist_ctrl_get_data/1"><c>erlang:dist_ctrl_get_data/1</c></seealso></p></item>
+	    <item><p><seealso marker="erts:erlang#dist_ctrl_get_data_notification/1"><c>erlang:dist_ctrl_get_data_notification/1</c></seealso></p></item>
+	    <item><p><seealso marker="erts:erlang#dist_ctrl_input_handler/2"><c>erlang:dist_ctrl_input_handler/2</c></seealso></p></item>
+	    <item><p><seealso marker="erts:erlang#dist_ctrl_put_data/2"><c>erlang:dist_ctrl_put_data/2</c></seealso></p></item>
+	  </list>
+	  <p>
+	    This function is called when the handshake has
+	    completed and the distribution channel is up.
+	    The distribution controller can begin dispatching
+	    traffic over the channel. This function is optional.
+	  </p>
+	  <p>Only used during handshake phase.</p>
+	</item>
+	
+	<tag><marker id="hs_data_add_flags"/><c>add_flags</c></tag>
+	<item>
+	  <p>
+	    <seealso marker="erl_dist_protocol#dflags">Distribution flags</seealso>
+	    to add to the connection. Currently all (non obsolete) flags will
+	    automatically be enabled.
+	  </p>
+	  <p>
+	    This flag field is optional.
+	  </p>
+	</item>
+
+	<tag><marker id="hs_data_reject_flags"/><c>reject_flags</c></tag>
+	<item>
+	  <p>
+	    <seealso marker="erl_dist_protocol#dflags">Distribution flags</seealso>
+	    to reject. Currently the following distribution flags can be rejected:
+	  </p>
+	  <taglist>
+	    <tag><c>DFLAG_DIST_HDR_ATOM_CACHE</c></tag>
+	    <item>Do not use atom cache over this connection.</item>
+	    <tag><c>DFLAGS_STRICT_ORDER_DELIVERY</c></tag>
+	    <item>Do not use any features that require strict
+	    order delivery.</item>
+	  </taglist>
+	  <p>
+	    This flag field is optional.
+	  </p>
+	</item>
+
+	<tag><marker id="hs_data_require_flags"/><c>require_flags</c></tag>
+	<item>
+	  <p>
+	    Require these <seealso marker="erl_dist_protocol#dflags">distribution
+	    flags</seealso> to be used. The connection will be aborted during the
+	    handshake if the other end does not use them.
+	  </p>
+	  <p>
+	    This flag field is optional.
+	  </p>
+	</item>
+
+      </taglist>
+    </section>
+
+    <section>
+      <marker id="distribution_data_delivery"/>
+      <title>Distribution Data Delivery</title>
+      <p>
+	When using the default configuration, the data to pass
+	over a connection needs to be delivered as is
+	to the node on the receiving end in the <em>exact same
+	order</em>, with no loss of data what so ever, as sent
+	from the sending node.
+      </p>
+      <p>
+	The data delivery order can be relaxed by disabling
+	features that require strict ordering. This is done by
+	passing the <c>?DFLAGS_STRICT_ORDER_DELIVERY</c>
+	<seealso marker="erl_dist_protocol#dflags">distribution
+	flags</seealso> in the
+	<seealso marker="alt_dist#hs_data_reject_flags"><c>reject_flags</c></seealso>
+	field of the <seealso marker="#hs_data_record"><c>#hs_data{}</c></seealso>
+	record used when setting up the connection. When relaxed
+	ordering is used, only the order of signals with the same
+	sender/receiver pair has to be preserved.
+	However, note that disabling the features that require
+	strict ordering may have a negative impact on performance,
+	throughput, and/or latency. 
+      </p>
+    </section>
+
+    <section>
+      <marker id="enable_your_distribution_module"/>
+      <title>Enable Your Distribution Module</title>
+
+      <p>For <c>net_kernel</c> to find out which distribution module to use,
+      the <c>erl</c> command-line argument <c>-proto_dist</c> is used. It
+      is followed by one or more distribution module names, with suffix
+      "_dist" removed. That is, <c>gen_tcp_dist</c> as a distribution module
+      is specified as <c>-proto_dist gen_tcp</c>.</p>
+
+      <p>If no <c>epmd</c> (TCP port mapper daemon) is used, also command-line
+      option <c>-no_epmd</c> is to be specified, which makes
+      Erlang skip the <c>epmd</c> startup, both as an OS process and as an
+      Erlang ditto.</p>
+    </section>
+
+  </section>
+
+  <section>
     <title>The Driver</title>
+
+    <note>
+      <p>This section was written a long time ago. Most of it is still
+      valid, but some things have changed since then. Some updates have
+      been made to the documentation of the driver presented here,
+      but more can be done and is planned for the future.
+      The reader is encouraged to read the
+      <seealso marker="erl_driver"><c>erl_driver</c></seealso> and
+      <seealso marker="driver_entry"><c>driver_entry</c></seealso>
+      documentation also.</p>
+    </note>
+
     <p>Although Erlang drivers in general can be beyond the scope of this
       section, a brief introduction seems to be in place.</p>
 
diff --git a/erts/doc/src/driver_entry.xml b/erts/doc/src/driver_entry.xml
index 2421e0a8d9..e8c7e26457 100644
--- a/erts/doc/src/driver_entry.xml
+++ b/erts/doc/src/driver_entry.xml
@@ -196,10 +196,7 @@ typedef struct erl_drv_entry {
 			 char **rbuf, ErlDrvSizeT rlen, unsigned int *flags);
                                 /* Works mostly like 'control', a synchronous
                                    call into the driver */
-    void (*event)(ErlDrvData drv_data, ErlDrvEvent event,
-                  ErlDrvEventData event_data);
-                                /* Called when an event selected by
-                                   driver_event() has occurred */
+    void* unused_event_callback;
     int extended_marker;        /* ERL_DRV_EXTENDED_MARKER */
     int major_version;          /* ERL_DRV_EXTENDED_MAJOR_VERSION */
     int minor_version;          /* ERL_DRV_EXTENDED_MINOR_VERSION */
diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml
index 638e88ca31..bd824b3405 100644
--- a/erts/doc/src/erl.xml
+++ b/erts/doc/src/erl.xml
@@ -538,20 +538,6 @@
         <p>Note that a distributed node will fail to start if epmd is
           not running.</p>
       </item>
-      <tag><marker id="smp"/><c><![CDATA[-smp [enable|auto|disable]]]></c></tag>
-      <item>
-        <p><c>-smp enable</c> and <c>-smp</c> start the Erlang runtime
-	  system with SMP support enabled. This can fail if no runtime
-	  system with SMP support is available. <c>-smp auto</c> starts
-	  the Erlang runtime system with SMP support enabled if it is
-	  available and more than one logical processor is detected.
-	  <c>-smp disable</c> starts a runtime system without SMP support.
-           The runtime system without SMP support is deprecated and will
-           be removed in a future major release.</p>
-        <note>
-          <p>See also flag<seealso marker="#+S"><c>+S</c></seealso>.</p>
-        </note>
-      </item>
       <tag><c><![CDATA[-version]]></c> (emulator flag)</tag>
       <item>
         <p>Makes the emulator print its version number. The same
@@ -776,13 +762,40 @@
           <seealso marker="erlang#process_flag_message_queue_data">
           <c>process_flag(message_queue_data, MQD)</c></seealso>.</p>
       </item>
-      <tag><c><![CDATA[+K true | false]]></c></tag>
+      <tag><marker id="+IOp"/><c>+IOp PollSets</c></tag>
       <item>
-        <p>Enables or disables the kernel poll functionality if supported by
-          the emulator. Defaults to <c><![CDATA[false]]></c> (disabled).
-          If the emulator does not support kernel poll, and flag
-          <c><![CDATA[+K]]></c> is passed to the emulator, a warning is
-          issued at startup.</p>
+        <p>Sets the number of IO pollsets to use when polling for I/O.
+          This option is only used on platforms that support concurrent
+          updates of a pollset, otherwise the same number of pollsets
+          are used as IO poll threads.
+          The default is 1.
+        </p>
+      </item>
+      <tag><marker id="+IOt"/><c>+IOt PollThreads</c></tag>
+      <item>
+        <p>Sets the number of IO poll threads to use when polling for I/O.
+          The maximum number of poll threads allowed is 1024. The default is 1.
+        </p>
+        <p>A good way to check if more IO poll threads are needed is to use
+          <seealso marker="runtime_tools:msacc">microstate accounting</seealso>
+          and see what the load of the IO poll thread is. If it is high it could
+          be a good idea to add more threads.</p>
+      </item>
+      <tag><marker id="+IOPp"/><c>+IOPp PollSetsPercentage</c></tag>
+      <item>
+        <p>Similar to <seealso marker="#+IOp"><c>+IOp</c></seealso> but uses
+          percentages to set the number of IO pollsets to create, based on the
+          number of poll threads configured. If both <c>+IOPp</c> and <c>+IOp</c>
+          are used, <c>+IOPp</c> is ignored.
+        </p>
+      </item>
+      <tag><marker id="+IOPt"/><c>+IOPt PollThreadsPercentage</c></tag>
+      <item>
+        <p>Similar to <seealso marker="#+IOt"><c>+IOt</c></seealso> but uses
+          percentages to set the number of IO poll threads to create, based on
+          the number of schedulers configured. If both <c>+IOPt</c> and
+          <c>+IOt</c> are used, <c>+IOPt</c> is ignored.
+        </p>
       </item>
       <tag><c><![CDATA[+l]]></c></tag>
       <item>
@@ -902,7 +915,7 @@
         <c><![CDATA[+S Schedulers:SchedulerOnline]]></c></tag>
       <item>
         <p>Sets the number of scheduler threads to create and scheduler threads
-          to set online when SMP support has been enabled. The maximum for both
+          to set online. The maximum for both
           values is 1024. If the Erlang runtime system is able to determine the
           number of logical processors configured and logical processors
           available, <c>Schedulers</c> defaults to logical processors
@@ -920,8 +933,6 @@
         <p>Specifying value <c>0</c> for <c>Schedulers</c> or
           <c>SchedulersOnline</c> resets the number of scheduler threads or
           scheduler threads online, respectively, to its default value.</p>
-        <p>This option is ignored if the emulator does not have SMP support
-          enabled (see flag <seealso marker="#smp"><c>-smp</c></seealso>).</p>
       </item>
       <tag><marker id="+SP"/><c><![CDATA[+SP
         SchedulersPercentage:SchedulersOnlinePercentage]]></c></tag>
@@ -929,8 +940,8 @@
         <p>Similar to <seealso marker="#+S"><c>+S</c></seealso> but uses
           percentages to set the number of scheduler threads to create, based
           on logical processors configured, and scheduler threads to set online,
-          based on logical processors available, when SMP support has been
-          enabled. Specified values must be &gt; 0. For example,
+          based on logical processors available.
+          Specified values must be &gt; 0. For example,
           <c>+SP 50:25</c> sets the number of scheduler threads to 50% of the
           logical processors configured, and the number of scheduler threads
           online to 25% of the logical processors available.
@@ -945,15 +956,13 @@
           and 8 logical cores available, the combination of the options
           <c>+S 4:4 +SP 50:25</c> (in either order) results in 2 scheduler
           threads (50% of 4) and 1 scheduler thread online (25% of 4).</p>
-        <p>This option is ignored if the emulator does not have SMP support
-          enabled (see flag <seealso marker="#smp"><c>-smp</c></seealso>).</p>
       </item>
       <tag><marker id="+SDcpu"/><c><![CDATA[+SDcpu
         DirtyCPUSchedulers:DirtyCPUSchedulersOnline]]></c></tag>
       <item>
         <p>Sets the number of dirty CPU scheduler threads to create and dirty
-          CPU scheduler threads to set online when threading support has been
-          enabled. The maximum for both values is 1024, and each value is
+          CPU scheduler threads to set online.
+          The maximum for both values is 1024, and each value is
           further limited by the settings for normal schedulers:</p>
         <list type="bulleted">
           <item>The number of dirty CPU scheduler threads created cannot exceed
@@ -977,16 +986,14 @@
 	  executing on ordinary schedulers. If the amount of dirty CPU
 	  schedulers was allowed to be unlimited, dirty CPU bound jobs would
 	  potentially starve normal jobs.</p>
-        <p>This option is ignored if the emulator does not have threading
-          support enabled.</p>
       </item>
       <tag><marker id="+SDPcpu"/><c><![CDATA[+SDPcpu
         DirtyCPUSchedulersPercentage:DirtyCPUSchedulersOnlinePercentage]]></c></tag>
       <item>
         <p>Similar to <seealso marker="#+SDcpu"><c>+SDcpu</c></seealso> but
           uses percentages to set the number of dirty CPU scheduler threads to
-          create and the number of dirty CPU scheduler threads to set online
-          when threading support has been enabled. Specified values must be
+          create and the number of dirty CPU scheduler threads to set online.
+          Specified values must be
           &gt; 0. For example, <c>+SDPcpu 50:25</c> sets the number of dirty
           CPU scheduler threads to 50% of the logical processors configured
           and the number of dirty CPU scheduler threads online to 25% of the
@@ -1003,13 +1010,11 @@
           the combination of the options <c>+SDcpu 4:4 +SDPcpu 50:25</c> (in
           either order) results in 2 dirty CPU scheduler threads (50% of 4) and
           1 dirty CPU scheduler thread online (25% of 4).</p>
-        <p>This option is ignored if the emulator does not have threading
-          support enabled.</p>
       </item>
       <tag><marker id="+SDio"/><c><![CDATA[+SDio DirtyIOSchedulers]]></c></tag>
       <item>
-        <p>Sets the number of dirty I/O scheduler threads to create when
-          threading support has been enabled. Valid range is 0-1024. By
+        <p>Sets the number of dirty I/O scheduler threads to create.
+          Valid range is 0-1024. By
           default, the number of dirty I/O scheduler threads created is 10,
           same as the default number of threads in the <seealso
           marker="#async_thread_pool_size">async thread pool</seealso>.</p>
@@ -1019,8 +1024,6 @@
 	  expected to execute on dirty I/O schedulers. If the user should schedule CPU
 	  bound jobs on dirty I/O schedulers, these jobs might starve ordinary
 	  jobs executing on ordinary schedulers.</p>
-        <p>This option is ignored if the emulator does not have threading
-          support enabled.</p>
       </item>
       <tag><c><![CDATA[+sFlag Value]]></c></tag>
       <item>
@@ -1297,25 +1300,6 @@
               <seealso marker="erlang#system_info_cpu_topology">
               <c>erlang:system_info(cpu_topology)</c></seealso>.</p>
           </item>
-          <tag><marker id="+secio"/><c>+secio true|false</c></tag>
-          <item>
-            <p>Enables or disables eager check I/O scheduling. Defaults
-              to <c>true</c>. The default was changed from <c>false</c>
-              as from ERTS 7.0. The behavior before this
-              flag was introduced corresponds to <c>+secio false</c>.</p>
-            <p>The flag effects when schedulers will check for I/O
-              operations possible to execute, and when such I/O operations
-              will execute. As the parameter name implies,
-              schedulers are more eager to check for I/O when
-              <c>true</c> is passed. This, however, also implies that
-              execution of outstanding I/O operation is not
-              prioritized to the same extent as when <c>false</c> is
-              passed.</p>
-            <p><seealso marker="erlang#system_info_eager_check_io">
-              <c>erlang:system_info(eager_check_io)</c></seealso>
-              returns the value of this parameter used when starting
-              the virtual machine.</p>
-          </item>
           <tag><marker id="+sfwi"/><c>+sfwi Interval</c></tag>
           <item>
             <p>Sets scheduler-forced wakeup interval. All run queues are
@@ -1657,9 +1641,7 @@
       <tag>The <c>.erlang</c> startup file</tag>
       <item>
         <p>When Erlang/OTP is started, the system searches for a file named
-          <c>.erlang</c> in the directory where Erlang/OTP is started. If not
-          found, the user's home directory is searched for an <c>.erlang</c>
-          file.</p>
+        <c>.erlang</c> in the user's home directory.</p>
         <p>If an <c>.erlang</c> file is found, it is assumed to contain valid
           Erlang expressions. These expressions are evaluated as if they were
           input to the shell.</p>
diff --git a/erts/doc/src/erl_dist_protocol.xml b/erts/doc/src/erl_dist_protocol.xml
index 610351db6c..a78b13aaa4 100644
--- a/erts/doc/src/erl_dist_protocol.xml
+++ b/erts/doc/src/erl_dist_protocol.xml
@@ -829,7 +829,31 @@ DiB == gen_digest(ChA, ICA)?
         <item>
           <p>The node understand UTF-8 encoded atoms.</p>
         </item>
+        <tag><c>-define(DFLAG_MAP_TAG, 16#20000).</c></tag>
+        <item>
+          <p>The node understand the map tag.</p>
+        </item>
+        <tag><c>-define(DFLAG_BIG_CREATION, 16#40000).</c></tag>
+        <item>
+          <p>The node understand big node creation.</p>
+        </item>
+        <tag><c>-define(DFLAG_SEND_SENDER, 16#80000).</c></tag>
+        <item>
+          <p>
+	    Use the <c>SEND_SENDER</c>
+	    <seealso marker="#control_message">control message</seealso>
+	    instead of the <c>SEND</c> control message and use the
+	    <c>SEND_SENDER_TT</c> control message instead
+	    of the <c>SEND_TT</c> control message.
+	  </p>
+        </item>
       </taglist>
+      <p>
+	There are also a collection of <c>DFLAG</c>s bitwise or:ed
+	together in the <c>DFLAGS_STRICT_ORDER_DELIVERY</c> macro.
+	These flags corresponds to features that require strict
+	ordering of data over distribution channels.
+      </p>
     </section>
   </section>
 
@@ -922,6 +946,7 @@ DiB == gen_digest(ChA, ICA)?
       </item>
     </taglist>
 
+    <marker id="control_message"/>
     <p>The <c>ControlMessage</c> is a tuple, where the first element indicates
       which distributed operation it encodes:</p>
 
@@ -1028,4 +1053,49 @@ DiB == gen_digest(ChA, ICA)?
       </item>
     </taglist>
   </section>
+
+  <section>
+    <title>New Ctrlmessages for Erlang/OTP 21</title>
+    <taglist>
+      <tag><c>SEND_SENDER</c></tag>
+      <item>
+        <p><c>{22, FromPid, ToPid}</c></p>
+        <p>Followed by <c>Message</c>.</p>
+	<p>
+	  This control messages replace the <c>SEND</c> control
+	  message and will be sent when the distribution flag
+	  <seealso marker="erl_dist_protocol#dflags"><c>DFLAG_SEND_SENDER</c></seealso>
+	  has been negotiated in the connection setup handshake.
+	</p>
+	<note><p>
+	  Messages encoded before the connection has
+	  been set up may still use the <c>SEND</c> control
+	  message. However, once a <c>SEND_SENDER</c> or <c>SEND_SENDER_TT</c>
+	  control message has been sent, no more <c>SEND</c>
+	  control messages will be sent in the same direction
+	  on the connection.
+	</p></note>
+      </item>
+      <tag><c>SEND_SENDER_TT</c></tag>
+      <item>
+        <p><c>{23, FromPid, ToPid, TraceToken}</c></p>
+        <p>Followed by <c>Message</c>.</p>
+	<p>
+	  This control messages replace the <c>SEND_TT</c> control
+	  message and will be sent when the distribution flag
+	  <seealso marker="erl_dist_protocol#dflags"><c>DFLAG_SEND_SENDER</c></seealso>
+	  has been negotiated in the connection setup handshake.
+	</p>
+	<note><p>
+	  Messages encoded before the connection has
+	  been set up may still use the <c>SEND_TT</c> control
+	  message. However, once a <c>SEND_SENDER</c> or <c>SEND_SENDER_TT</c>
+	  control message has been sent, no more <c>SEND_TT</c>
+	  control messages will be sent in the same direction
+	  on the connection.
+	</p></note>
+      </item>
+    </taglist>
+  </section>
+
 </chapter>
diff --git a/erts/doc/src/erl_driver.xml b/erts/doc/src/erl_driver.xml
index 5705100ab2..ca9d458e1e 100644
--- a/erts/doc/src/erl_driver.xml
+++ b/erts/doc/src/erl_driver.xml
@@ -157,7 +157,7 @@
     </note>
 
     <p>Most functions in this API are <em>not</em> thread-safe, that is,
-      they <em>cannot</em> be called from any thread. Functions
+      they <em>cannot</em> be called from arbitrary threads. Functions
       that are not documented as thread-safe can only be called from
       driver callbacks or function calls descending from a driver
       callback call. Notice that driver callbacks can be called from
diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml
index ef3cdb89e9..23f0c66429 100644
--- a/erts/doc/src/erl_nif.xml
+++ b/erts/doc/src/erl_nif.xml
@@ -367,6 +367,8 @@ return term;</code>
             <c>enif_ioq_deq()</c></seealso></item>
             <item><seealso marker="#enif_ioq_peek">
             <c>enif_ioq_peek()</c></seealso></item>
+            <item><seealso marker="#enif_ioq_peek_head">
+            <c>enif_ioq_peek_head()</c></seealso></item>
             <item><seealso marker="#enif_inspect_iovec">
             <c>enif_inspect_iovec()</c></seealso></item>
             <item><seealso marker="#enif_free_iovec">
@@ -1683,8 +1685,7 @@ enif_inspect_iovec(env, max_elements, term, &amp;tail, &amp;iovec);
       <fsummary>Peek inside the IO Queue</fsummary>
       <desc>
         <p>Get the I/O queue as a pointer to an array of <c>SysIOVec</c>s.
-          It also returns the number of elements in <c>iovlen</c>.
-          This is the only way to get data out of the queue.</p>
+           It also returns the number of elements in <c>iovlen</c>.</p>
         <p>Nothing is removed from the queue by this function, that must be done
           with <seealso marker="#enif_ioq_deq"><c>enif_ioq_deq</c></seealso>.</p>
          <p>The returned array is suitable to use with the Unix system
@@ -1693,6 +1694,21 @@ enif_inspect_iovec(env, max_elements, term, &amp;tail, &amp;iovec);
     </func>
 
     <func>
+      <name><ret>int</ret>
+      <nametext>enif_ioq_peek_head(ErlNifEnv *env, ErlNifIOQueue *q, size_t *size, ERL_NIF_TERM *bin_term)</nametext></name>
+      <fsummary>Peek the head of the IO Queue.</fsummary>
+      <desc>
+        <p>Get the head of the IO Queue as a binary term.</p>
+        <p>If <c>size</c> is not <c>NULL</c>, the size of the head is placed
+           there.</p>
+        <p>Nothing is removed from the queue by this function, that must be done
+           with <seealso marker="#enif_ioq_deq"><c>enif_ioq_deq</c></seealso>.</p>
+        <p>Returns <c>true</c> on success, or <c>false</c> if the queue is
+           empty.</p>
+      </desc>
+    </func>
+
+    <func>
       <name><ret>size_t</ret>
       <nametext>enif_ioq_size(ErlNifIOQueue *q)</nametext></name>
       <fsummary>Get the current size of the IO Queue</fsummary>
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index b04f2b008e..d7404fa3ce 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -189,6 +189,14 @@
 	</taglist>
       </desc>
     </datatype>
+
+    <datatype>
+      <name name="dist_handle"></name>
+      <desc>
+        <p>An opaque handle identifing a distribution channel.</p>
+      </desc>
+    </datatype>
+
   </datatypes>
 
   <funcs>
@@ -549,9 +557,7 @@ hello
       <name name="binary_to_term" arity="2"/>
       <fsummary>Decode an Erlang external term format binary.</fsummary>
       <desc>
-        <p>As <c>binary_to_term/1</c>, but takes options that affect decoding
-          of the binary.</p>
-        <p>Option:</p>
+        <p>As <c>binary_to_term/1</c>, but takes these options:</p>
         <taglist>
           <tag><c>safe</c></tag>
           <item>
@@ -567,18 +573,31 @@ hello
               creation of new external function references.
               None of those resources are garbage collected, so unchecked
               creation of them can exhaust available memory.</p>
-          </item>
-        </taglist>
-        <p>Failure: <c>badarg</c> if <c>safe</c> is specified and unsafe
-          data is decoded.</p>
         <pre>
-> <input>binary_to_term(&lt;&lt;131,100,0,5,104,101,108,108,111>>, [safe]).</input>
+> <input>binary_to_term(&lt;&lt;131,100,0,5,"hello">>, [safe]).</input>
 ** exception error: bad argument
 > <input>hello.</input>
 hello
-> <input>binary_to_term(&lt;&lt;131,100,0,5,104,101,108,108,111>>, [safe]).</input>
+> <input>binary_to_term(&lt;&lt;131,100,0,5,"hello">>, [safe]).</input>
 hello
 </pre>
+          </item>
+          <tag><c>used</c></tag>
+          <item>
+	    <p>Changes the return value to <c>{Term, Used}</c> where <c>Used</c>
+	    is the number of bytes actually read from <c>Binary</c>.</p>
+        <pre>
+> <input>Input = &lt;&lt;131,100,0,5,"hello","world">>.</input>
+&lt;&lt;131,100,0,5,104,101,108,108,111,119,111,114,108,100>>
+> <input>{Term, Used} = binary_to_term(Input, [used]).</input>
+{hello, 9}
+> <input>split_binary(Input, Used).</input>
+{&lt;&lt;131,100,0,5,104,101,108,108,111>>, &lt;&lt;"world">>}
+</pre>
+          </item>
+        </taglist>
+        <p>Failure: <c>badarg</c> if <c>safe</c> is specified and unsafe
+          data is decoded.</p>
         <p>See also
           <seealso marker="#term_to_binary/1"><c>term_to_binary/1</c></seealso>,
           <seealso marker="#binary_to_term/1">
@@ -1233,6 +1252,141 @@ end</code>
     </func>
 
     <func>
+      <name name="dist_ctrl_get_data" arity="1"/>
+      <fsummary>Get distribution channel data to pass to another node.</fsummary>
+      <desc>
+        <p>
+	  Get distribution channel data from the local node that is
+	  to be passed to the remote node. The distribution channel
+	  is identified by <c><anno>DHandle</anno></c>. If no data
+	  is available, the atom <c>none</c> is returned. One
+	  can request to be informed by a message when more
+	  data is available by calling
+	  <seealso marker="erlang#dist_ctrl_get_data_notification/1"><c>erlang:dist_ctrl_get_data_notification(DHandle)</c></seealso>.
+	</p>
+	<note><p>
+	  Only the process registered as distribution
+	  controller for the distribution channel identified by
+	  <c><anno>DHandle</anno></c> is allowed to call this
+	  function.
+	</p></note>
+	<p>
+	  This function is used when implementing an alternative
+	  distribution carrier using processes as distribution
+	  controllers. <c><anno>DHandle</anno></c> is retrived
+	  via the callback
+	  <seealso marker="erts:alt_dist#hs_data_f_handshake_complete"><c>f_handshake_complete</c></seealso>.
+	  More information can be found in the documentation of
+	  <seealso marker="erts:alt_dist#distribution_module">ERTS
+	  User's Guide ➜ How to implement an Alternative Carrier
+	  for the Erlang Distribution ➜ Distribution Module</seealso>.
+	</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="dist_ctrl_get_data_notification" arity="1"/>
+      <fsummary>Request notification about available outgoing distribution channel data.</fsummary>
+      <desc>
+        <p>
+	  Request notification when more data is available to
+	  fetch using
+	  <seealso marker="erlang#dist_ctrl_get_data/1"><c>erlang:dist_ctrl_get_data(DHandle)</c></seealso>
+	  for the distribution channel identified by
+	  <c><anno>DHandle</anno></c>. When more data is present,
+	  the caller will be sent the message <c>dist_data</c>.
+	  Once a <c>dist_data</c> messages has been sent, no
+	  more <c>dist_data</c> messages will be sent until
+	  the <c>dist_ctrl_get_data_notification/1</c> function has been called
+	  again.
+	</p>
+	<note><p>
+	  Only the process registered as distribution
+	  controller for the distribution channel identified by
+	  <c><anno>DHandle</anno></c> is allowed to call this
+	  function.
+	</p></note>
+	<p>
+	  This function is used when implementing an alternative
+	  distribution carrier using processes as distribution
+	  controllers. <c><anno>DHandle</anno></c> is retrived
+	  via the callback
+	  <seealso marker="erts:alt_dist#hs_data_f_handshake_complete"><c>f_handshake_complete</c></seealso>.
+	  More information can be found in the documentation of
+	  <seealso marker="erts:alt_dist#distribution_module">ERTS
+	  User's Guide ➜ How to implement an Alternative Carrier
+	  for the Erlang Distribution ➜ Distribution Module</seealso>.
+	</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="dist_ctrl_input_handler" arity="2"/>
+      <fsummary>Register distribution channel input handler process.</fsummary>
+      <desc>
+        <p>
+	  Register an alternate input handler process for the
+	  distribution channel identified by <c><anno>DHandle</anno></c>.
+	  Once this function has been called, <c><anno>InputHandler</anno></c>
+	  is the only process allowed to call
+	  <seealso marker="erlang#dist_ctrl_put_data/2"><c>erlang:dist_ctrl_put_data(DHandle, Data)</c></seealso>
+	  with the <c><anno>DHandle</anno></c> identifing this distribution
+	  channel.
+	</p>
+	<note><p>
+	  Only the process registered as distribution
+	  controller for the distribution channel identified by
+	  <c><anno>DHandle</anno></c> is allowed to call this
+	  function.
+	</p></note>
+	<p>
+	  This function is used when implementing an alternative
+	  distribution carrier using processes as distribution
+	  controllers. <c><anno>DHandle</anno></c> is retrived
+	  via the callback
+	  <seealso marker="erts:alt_dist#hs_data_f_handshake_complete"><c>f_handshake_complete</c></seealso>.
+	  More information can be found in the documentation of
+	  <seealso marker="erts:alt_dist#distribution_module">ERTS
+	  User's Guide ➜ How to implement an Alternative Carrier
+	  for the Erlang Distribution ➜ Distribution Module</seealso>.
+	</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="dist_ctrl_put_data" arity="2"/>
+      <fsummary>Pass data into the VM from a distribution channel.</fsummary>
+      <desc>
+        <p>
+	  Deliver distribution channel data from a remote node to the
+	  local node.
+	</p>
+	<note><p>
+	  Only the process registered as distribution
+	  controller for the distribution channel identified by
+	  <c><anno>DHandle</anno></c> is allowed to call this
+	  function unless an alternate input handler process
+	  has been registered using
+	  <seealso marker="erlang#dist_ctrl_input_handler/2"><c>erlang:dist_ctrl_input_handler(DHandle, InputHandler)</c></seealso>.
+	  If an alternate input handler has been registered, only
+	  the registered input handler process is allowed to call
+	  this function.
+	</p></note>
+	<p>
+	  This function is used when implementing an alternative
+	  distribution carrier using processes as distribution
+	  controllers. <c><anno>DHandle</anno></c> is retrived
+	  via the callback
+	  <seealso marker="erts:alt_dist#hs_data_f_handshake_complete"><c>f_handshake_complete</c></seealso>.
+	  More information can be found in the documentation of
+	  <seealso marker="erts:alt_dist#distribution_module">ERTS
+	  User's Guide ➜ How to implement an Alternative Carrier
+	  for the Erlang Distribution ➜ Distribution Module</seealso>.
+	</p>
+      </desc>
+    </func>
+
+    <func>
       <name name="element" arity="2"/>
       <fsummary>Return the Nth element of a tuple.</fsummary>
       <type_desc variable="N">1..tuple_size(<anno>Tuple</anno>)</type_desc>
@@ -1831,39 +1985,26 @@ true</pre>
       <fsummary>Get the call stack back-trace of the last exception.</fsummary>
       <type name="stack_item"/>
       <desc>
-        <p>Gets the call stack back-trace (<em>stacktrace</em>) for an
-          exception that has just been caught
-	  in the calling process as a list of
-          <c>{<anno>Module</anno>,<anno>Function</anno>,<anno>Arity</anno>,<anno>Location</anno>}</c>
-          tuples. Field <c><anno>Arity</anno></c> in the first tuple can be the
-          argument list of that function call instead of an arity integer,
-          depending on the exception.</p>
-        <p>If there has not been any exceptions in a process, the
-          stacktrace is <c>[]</c>. After a code change for the process,
-          the stacktrace can also be reset to <c>[]</c>.</p>
-	<p><c>erlang:get_stacktrace/0</c> is only guaranteed to return
-	a stacktrace if called (directly or indirectly) from within the
-	scope of a <c>try</c> expression. That is, the following call works:</p>
+	<warning><p><c>erlang:get_stacktrace/0</c> is deprecated and will stop working
+	in a future release.</p></warning>
+      <p>Instead of using <c>erlang:get_stacktrace/0</c> to retrieve
+      the call stack back-trace, use the following syntax:</p>
 <pre>
 try Expr
 catch
-  C:R ->
-   {C,R,erlang:get_stacktrace()}
+  Class:Reason:Stacktrace ->
+   {Class,Reason,Stacktrace}
 end</pre>
-	<p>As does this call:</p>
-<pre>
-try Expr
-catch
-  C:R ->
-   {C,R,helper()}
-end
-
-helper() ->
-  erlang:get_stacktrace().</pre>
-
-        <warning><p>In a future release,
-        <c>erlang:get_stacktrace/0</c> will return <c>[]</c> if called
-        from outside a <c>try</c> expression.</p></warning>
+        <p><c>erlang:get_stacktrace/0</c> retrieves the call stack back-trace
+        (<em>stacktrace</em>) for an exception that has just been
+        caught in the calling process as a list of
+        <c>{<anno>Module</anno>,<anno>Function</anno>,<anno>Arity</anno>,<anno>Location</anno>}</c>
+        tuples. Field <c><anno>Arity</anno></c> in the first tuple can
+        be the argument list of that function call instead of an arity
+        integer, depending on the exception.</p>
+        <p>If there has not been any exceptions in a process, the
+          stacktrace is <c>[]</c>. After a code change for the process,
+          the stacktrace can also be reset to <c>[]</c>.</p>
         <p>The stacktrace is the same data as operator <c>catch</c>
           returns, for example:</p>
         <pre>
@@ -1886,6 +2027,18 @@ helper() ->
             where the exception occurred or the function was called.
           </item>
         </taglist>
+        <warning><p>Developers should rely on stacktrace entries only for
+          debugging purposes.</p>
+          <p>The VM performs tail call optimization, which
+          does not add new entries to the stacktrace, and also limits stacktraces
+          to a certain depth. Furthermore, compiler options, optimizations and
+          future changes may add or remove stacktrace entries, causing any code
+          that expects the stacktrace to be in a certain order or contain specific
+          items to fail.</p>
+          <p>The only exception to this rule is <c>error:undef</c> which
+          guarantees to include the <anno>Module</anno>, <anno>Function</anno> and <anno>Arity</anno>
+          of the attempted function as the first stacktrace entry.</p>
+        </warning>	
         <p>See also
           <seealso marker="#error/1"><c>error/1</c></seealso> and
           <seealso marker="#error/2"><c>error/2</c></seealso>.</p>
@@ -3195,25 +3348,6 @@ RealSystem = system + MissedSystem</code>
               monitored process resides). </p></item>
         </taglist>
 
-        <p>If an attempt is made to monitor a process on an older node
-          (where remote process monitoring is not implemented or
-          where remote process monitoring by registered name is not
-          implemented), the call fails with <c>badarg</c>.</p>
-        <note>
-          <p>The format of the <c>'DOWN'</c> message changed in ERTS
-            5.2 (Erlang/OTP R9B) for monitoring
-            <em>by registered name</em>. Element <c>Object</c> of
-            the <c>'DOWN'</c> message could in earlier versions
-            sometimes be the process identifier of the monitored process and sometimes
-            be the registered name. Now element <c>Object</c> is
-            always a tuple consisting of the registered name and
-            the node name. Processes on new nodes (ERTS 5.2
-            or higher versions) always get <c>'DOWN'</c> messages on
-            the new format even if they are monitoring processes on old
-            nodes. Processes on old nodes always get <c>'DOWN'</c>
-            messages on the old format.</p>
-        </note>
-
         <taglist>
         <tag>Monitoring a <marker id="monitor_process"/><c>process</c></tag>
         <item>
@@ -3221,7 +3355,19 @@ RealSystem = system + MissedSystem</code>
             process identified by <c><anno>Item</anno></c>, which can be a
             <c>pid()</c> (local or remote), an atom <c>RegisteredName</c> or
             a tuple <c>{RegisteredName, Node}</c> for a registered process,
-            located elsewhere.</p>
+          located elsewhere.</p>
+
+        <note><p>Before ERTS 10.0 (OTP 21.0), monitoring a process could fail with
+	  <c>badarg</c> if the monitored process resided on a primitive node
+	  (such as erl_interface or jinterface), where remote process monitoring
+	  is not implemented.</p>
+	  <p>Now, such a call to <c>monitor</c> will instead succeed and a
+	  monitor is created. But the monitor will only supervise the
+	  connection. That is, a <c>{'DOWN', _, process, _, noconnection}</c> is
+	  the only message that may be received, as the primitive node have no
+	  way of reporting the status of the monitored process.</p>
+	</note>
+
         </item>
 
         <tag>Monitoring a <marker id="monitor_port"/><c>port</c></tag>
@@ -3686,6 +3832,12 @@ RealSystem = system + MissedSystem</code>
           </item>
           <tag><c>{env, <anno>Env</anno>}</c></tag>
           <item>
+	    <p>
+	      Types:<br/>
+	      &nbsp;&nbsp;<c><anno>Name</anno> = </c><seealso marker="kernel:os#type-env_var_name"><c>os:env_var_name()</c></seealso><br/>
+	      &nbsp;&nbsp;<c><anno>Val</anno> = </c><seealso marker="kernel:os#type-env_var_value"><c>os:env_var_value()</c></seealso><c> | false</c><br/>
+	      &nbsp;&nbsp;<c>Env = [{<anno>Name</anno>, <anno>Val</anno>}]</c>
+	    </p>
             <p>Only valid for <c>{spawn, <anno>Command</anno>}</c>, and
               <c>{spawn_executable, <anno>FileName</anno>}</c>.
               The environment of the started process is extended using
@@ -3700,7 +3852,13 @@ RealSystem = system + MissedSystem</code>
               exception is <c><anno>Val</anno></c> being the atom
               <c>false</c> (in analogy with
               <seealso marker="kernel:os#getenv/1"><c>os:getenv/1</c></seealso>,
-              which removes the environment variable.</p>
+              which removes the environment variable.
+	    </p>
+	    <p>
+	      For information about encoding requirements, see documentation
+	      of the types for <c><anno>Name</anno></c> and
+	      <c><anno>Val</anno></c>.
+	    </p>
           </item>
           <tag><c>{args, [ string() | binary() ]}</c></tag>
           <item>
@@ -4326,7 +4484,6 @@ RealSystem = system + MissedSystem</code>
       <desc>
         <p><c><anno>Locking</anno></c> is one of the following:</p>
         <list type="bulleted">
-          <item><c>false</c> (emulator without SMP support)</item>
           <item><c>port_level</c> (port-specific locking)</item>
           <item><c>driver_level</c> (driver-specific locking)</item>
         </list>
@@ -4567,11 +4724,11 @@ RealSystem = system + MissedSystem</code>
     </func>
 
     <func>
-      <name name="process_flag" arity="2" clause_i="3"/>
+      <name name="process_flag" arity="2" clause_i="3"
+	    anchor="process_flag_min_heap_size"/>
       <fsummary>Set process flag min_heap_size for the calling process.
       </fsummary>
       <desc>
-        <marker id="process_flag_min_heap_size"/>
         <p>Changes the minimum heap size for the calling process.</p>
         <p>Returns the old value of the flag.</p>
       </desc>
@@ -4589,12 +4746,12 @@ RealSystem = system + MissedSystem</code>
     </func>
 
     <func>
-      <name name="process_flag" arity="2" clause_i="5"/>
+      <name name="process_flag" arity="2" clause_i="5"
+	    anchor="process_flag_max_heap_size"/>
       <fsummary>Set process flag max_heap_size for the calling process.
       </fsummary>
       <type name="max_heap_size"/>
       <desc>
-        <marker id="process_flag_max_heap_size"/>
         <p>This flag sets the maximum heap size for the calling process.
           If <c><anno>MaxHeapSize</anno></c> is an integer, the system default
           values for <c>kill</c> and <c>error_logger</c> are used.
@@ -4663,12 +4820,12 @@ RealSystem = system + MissedSystem</code>
     </func>
 
     <func>
-      <name name="process_flag" arity="2" clause_i="6"/>
+      <name name="process_flag" arity="2" clause_i="6"
+	    anchor="process_flag_message_queue_data"/>
       <fsummary>Set process flag message_queue_data for the calling process.
       </fsummary>
       <type name="message_queue_data"/>
       <desc>
-        <marker id="process_flag_message_queue_data"/>
         <p>This flag determines how messages in the message queue
           are stored, as follows:</p>
         <taglist>
@@ -4705,11 +4862,12 @@ RealSystem = system + MissedSystem</code>
     </func>
 
     <func>
-      <name name="process_flag" arity="2" clause_i="7"/>
+      <name name="process_flag" arity="2" clause_i="7"
+	    anchor="process_flag_priority"/>
       <fsummary>Set process flag priority for the calling process.</fsummary>
       <type name="priority_level"/>
       <desc>
-        <p><marker id="process_flag_priority"></marker>
+        <p>
           Sets the process priority. <c><anno>Level</anno></c> is an atom.
           Four priority levels exist: <c>low</c>,
           <c>normal</c>, <c>high</c>, and <c>max</c>. Default
@@ -4730,8 +4888,8 @@ RealSystem = system + MissedSystem</code>
           selected for execution. Notice however that this does
           <em>not</em> mean that no processes on priority <c>low</c>
           or <c>normal</c> can run when processes
-          are running on priority <c>high</c>. On the runtime
-          system with SMP support, more processes can be running
+          are running on priority <c>high</c>. When using multiple
+          schedulers, more processes can be running
           in parallel than processes on priority <c>high</c>. That is,
           a <c>low</c> and a <c>high</c> priority process can
           execute at the same time.</p>
@@ -4746,10 +4904,8 @@ RealSystem = system + MissedSystem</code>
           execution.</p>
         <note>
           <p>Do not depend on the scheduling
-          to remain exactly as it is today. Scheduling, at least on
-          the runtime system with SMP support, is likely to be
-          changed in a future release to use available
-          processor cores better.</p>
+          to remain exactly as it is today. Scheduling is likely to be
+          changed in a future release to use available processor cores better.</p>
         </note>
         <p>There is <em>no</em> automatic mechanism for
           avoiding priority inversion, such as priority inheritance
@@ -6190,10 +6346,10 @@ true</pre>
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="1"/>
+      <name name="statistics" arity="1" clause_i="1"
+	    anchor="statistics_active_tasks"/>
       <fsummary>Information about active processes and ports.</fsummary>
       <desc>
-        <marker id="statistics_active_tasks"></marker>
         <p>Returns the same as
 	<seealso marker="#statistics_active_tasks_all">
         <c>statistics(active_tasks_all)</c></seealso>
@@ -6205,10 +6361,10 @@ true</pre>
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="2"/>
+      <name name="statistics" arity="1" clause_i="2"
+	    anchor="statistics_active_tasks_all"/>
       <fsummary>Information about active processes and ports.</fsummary>
       <desc>
-        <marker id="statistics_active_tasks_all"></marker>
         <p>Returns a list where each element represents the amount
           of active processes and ports on each run queue and its
           associated schedulers. That is, the number of processes and
@@ -6256,17 +6412,16 @@ true</pre>
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="4"/>
+      <name name="statistics" arity="1" clause_i="4"
+	    anchor="statistics_exact_reductions"/>
       <fsummary>Information about exact reductions.</fsummary>
       <desc>
-        <marker id="statistics_exact_reductions"></marker>
         <p>Returns the number of exact reductions.</p>
         <note>
           <p><c>statistics(exact_reductions)</c> is
             a more expensive operation than
             <seealso marker="#statistics_reductions">
-            statistics(reductions)</seealso>,
-            especially on an Erlang machine with SMP support.</p>
+            statistics(reductions)</seealso>.</p>
         </note>
       </desc>
     </func>
@@ -6295,10 +6450,10 @@ true</pre>
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="7"/>
+      <name name="statistics" arity="1" clause_i="7"
+	    anchor="statistics_microstate_accounting"/>
       <fsummary>Information about microstate accounting.</fsummary>
       <desc>
-        <marker id="statistics_microstate_accounting"></marker>
         <p>Microstate accounting can be used to measure how much time the Erlang
           runtime system spends doing various tasks. It is designed to be as
           lightweight as possible, but some overhead exists when this
@@ -6343,17 +6498,24 @@ lists:map(
         <p><c><anno>MSAcc_Thread_Type</anno></c>s:</p>
         <taglist>
           <tag><c>scheduler</c></tag>
-          <item>The main execution threads that do most of the work.</item>
+          <item>The main execution threads that do most of the work. See
+            <seealso marker="erts:erl#+S">erl +S</seealso> for more details.</item>
           <tag><c>dirty_cpu_scheduler</c></tag>
-          <item>The threads for long running cpu intensive work.</item>
+          <item>The threads for long running cpu intensive work. See
+            <seealso marker="erts:erl#+SDcpu">erl +SDcpu</seealso> for more details.</item>
           <tag><c>dirty_io_scheduler</c></tag>
-          <item>The threads for long running I/O work.</item>
+          <item>The threads for long running I/O work. See
+            <seealso marker="erts:erl#+SDio">erl +SDio</seealso> for more details.</item>
           <tag><c>async</c></tag>
           <item>Async threads are used by various linked-in drivers (mainly the
-            file drivers) do offload non-CPU intensive work.</item>
+            file drivers) do offload non-CPU intensive work. See
+            <seealso marker="erts:erl#+async_thread_pool_size">erl +A</seealso> for more details.</item>
           <tag><c>aux</c></tag>
           <item>Takes care of any work that is not
             specifically assigned to a scheduler.</item>
+          <tag><c>poll</c></tag>
+          <item>Does the IO polling for the emulator. See
+            <seealso marker="erts:erl#+IOt">erl +IOt</seealso> for more details.</item>
         </taglist>
         <p>The following <c><anno>MSAcc_Thread_State</anno></c>s are available.
           All states are exclusive, meaning that a thread cannot be in two
@@ -6431,10 +6593,10 @@ lists:map(
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="8"/>
+      <name name="statistics" arity="1" clause_i="8"
+	    anchor="statistics_reductions"/>
       <fsummary>Information about reductions.</fsummary>
       <desc>
-        <marker id="statistics_reductions"></marker>
         <p>Returns information about reductions, for example:</p>
         <pre>
 > <input>statistics(reductions).</input>
@@ -6450,9 +6612,10 @@ lists:map(
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="9"/>
+      <name name="statistics" arity="1" clause_i="9"
+	    anchor="statistics_run_queue"/>
       <fsummary>Information about the run-queues.</fsummary>
-      <desc><marker id="statistics_run_queue"></marker>
+      <desc>
         <p>Returns the total length of all normal run-queues. That is, the number
           of processes and ports that are ready to run on all available
           normal run-queues. Dirty run queues are not part of the
@@ -6466,9 +6629,10 @@ lists:map(
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="10"/>
+      <name name="statistics" arity="1" clause_i="10"
+	    anchor="statistics_run_queue_lengths"/>
       <fsummary>Information about the run-queue lengths.</fsummary>
-      <desc><marker id="statistics_run_queue_lengths"></marker>
+      <desc>
         <p>Returns the same as
 	<seealso marker="#statistics_run_queue_lengths_all">
         <c>statistics(run_queue_lengths_all)</c></seealso>
@@ -6480,9 +6644,10 @@ lists:map(
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="11"/>
+      <name name="statistics" arity="1" clause_i="11"
+	    anchor="statistics_run_queue_lengths_all"/>
       <fsummary>Information about the run-queue lengths.</fsummary>
-      <desc><marker id="statistics_run_queue_lengths_all"></marker>
+      <desc>
         <p>Returns a list where each element represents the amount
           of processes and ports ready to run for each run queue.
 	  Values for normal run queues are located first in the
@@ -6540,10 +6705,10 @@ lists:map(
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="13"/>
+      <name name="statistics" arity="1" clause_i="13"
+	    anchor="statistics_scheduler_wall_time"/>
       <fsummary>Information about each schedulers work time.</fsummary>
       <desc>
-        <marker id="statistics_scheduler_wall_time"></marker>
         <p>Returns a list of tuples with
           <c>{<anno>SchedulerId</anno>, <anno>ActiveTime</anno>,
           <anno>TotalTime</anno>}</c>, where
@@ -6650,8 +6815,8 @@ ok
 	than available logical processors, this value may
 	be greater than <c>1.0</c>.</p>
 	<p>As of ERTS version 9.0, the Erlang runtime system
-	with SMP support will as default have more schedulers
-	than logical processors. This due to the dirty schedulers.</p>
+        will as default have more schedulers than logical processors.
+        This due to the dirty schedulers.</p>
         <note>
           <p><c>scheduler_wall_time</c> is by default disabled. To
             enable it, use
@@ -6661,10 +6826,10 @@ ok
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="14"/>
+      <name name="statistics" arity="1" clause_i="14"
+	    anchor="statistics_scheduler_wall_time_all"/>
       <fsummary>Information about each schedulers work time.</fsummary>
       <desc>
-        <marker id="statistics_scheduler_wall_time_all"></marker>
 	<p>The same as
 	<seealso marker="#statistics_scheduler_wall_time"><c>statistics(scheduler_wall_time)</c></seealso>,
 	except that it also include information about all dirty I/O
@@ -6686,9 +6851,10 @@ ok
       </desc>
     </func>
     <func>
-      <name name="statistics" arity="1" clause_i="15"/>
+      <name name="statistics" arity="1" clause_i="15"
+	    anchor="statistics_total_active_tasks"/>
       <fsummary>Information about active processes and ports.</fsummary>
-      <desc><marker id="statistics_total_active_tasks"></marker>
+      <desc>
         <p>The same as calling
 	<c>lists:sum(</c><seealso marker="#statistics_active_tasks"><c>statistics(active_tasks)</c></seealso><c>)</c>,
 	but more efficient.</p>
@@ -6696,9 +6862,10 @@ ok
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="16"/>
+      <name name="statistics" arity="1" clause_i="16"
+	    anchor="statistics_total_active_tasks_all"/>
       <fsummary>Information about active processes and ports.</fsummary>
-      <desc><marker id="statistics_total_active_tasks_all"></marker>
+      <desc>
         <p>The same as calling
 	<c>lists:sum(</c><seealso marker="#statistics_active_tasks_all"><c>statistics(active_tasks_all)</c></seealso><c>)</c>,
 	but more efficient.</p>
@@ -6706,9 +6873,10 @@ ok
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="17"/>
+      <name name="statistics" arity="1" clause_i="17"
+	    anchor="statistics_total_run_queue_lengths"/>
       <fsummary>Information about the run-queue lengths.</fsummary>
-      <desc><marker id="statistics_total_run_queue_lengths"></marker>
+      <desc>
         <p>The same as calling
 	<c>lists:sum(</c><seealso marker="#statistics_run_queue_lengths"><c>statistics(run_queue_lengths)</c></seealso><c>)</c>,
 	but more efficient.</p>
@@ -6716,9 +6884,10 @@ ok
     </func>
 
     <func>
-      <name name="statistics" arity="1" clause_i="18"/>
+      <name name="statistics" arity="1" clause_i="18"
+	    anchor="statistics_total_run_queue_lengths_all"/>
       <fsummary>Information about the run-queue lengths.</fsummary>
-      <desc><marker id="statistics_total_run_queue_lengths_all"></marker>
+      <desc>
         <p>The same as calling
 	<c>lists:sum(</c><seealso marker="#statistics_run_queue_lengths_all"><c>statistics(run_queue_lengths_all)</c></seealso><c>)</c>,
 	but more efficient.</p>
@@ -6866,7 +7035,8 @@ ok
     </func>
 
     <func>
-      <name name="system_flag" arity="2" clause_i="2"/>
+      <name name="system_flag" arity="2" clause_i="2"
+	    anchor="system_flag_cpu_topology"/>
       <fsummary>Set system flag <c>cpu_topology</c>.</fsummary>
       <type name="cpu_topology"/>
       <type name="level_entry"/>
@@ -6875,7 +7045,7 @@ ok
       <type name="info_list"/>
       <desc>
         <warning>
-          <p><marker id="system_flag_cpu_topology"></marker>
+          <p>
             <em>This argument is deprecated.</em>
             Instead of using this argument, use command-line argument
             <seealso marker="erts:erl#+sct"><c>+sct</c></seealso> in
@@ -6913,10 +7083,11 @@ ok
     </func>
 
     <func>
-      <name name="system_flag" arity="2" clause_i="3"/>
+      <name name="system_flag" arity="2" clause_i="3"
+	    anchor="system_flag_dirty_cpu_schedulers_online"/>
       <fsummary>Set system_flag_dirty_cpu_schedulers_online.</fsummary>
       <desc>
-        <p><marker id="system_flag_dirty_cpu_schedulers_online"></marker>
+        <p>
           Sets the number of dirty CPU schedulers online. Range is
           <c><![CDATA[1 <= DirtyCPUSchedulersOnline <= N]]></c>, where <c>N</c>
           is the smallest of the return values of
@@ -6960,10 +7131,11 @@ ok
     </func>
 
     <func>
-      <name name="system_flag" arity="2" clause_i="5"/>
+      <name name="system_flag" arity="2" clause_i="5"
+	    anchor="system_flag_microstate_accounting"/>
       <fsummary>Set system flag microstate_accounting.</fsummary>
       <desc>
-        <p><marker id="system_flag_microstate_accounting"></marker>
+        <p>
           Turns on/off microstate accounting measurements. When passing reset,
           all counters are reset to 0.</p>
         <p>For more information see
@@ -7005,28 +7177,29 @@ ok
     </func>
 
     <func>
-      <name name="system_flag" arity="2" clause_i="8"/>
+      <name name="system_flag" arity="2" clause_i="8"
+	    anchor="system_flag_max_heap_size"/>
       <fsummary>Set system flag max_heap_size.</fsummary>
       <type name="max_heap_size"/>
       <desc>
-        <marker id="system_flag_max_heap_size"></marker>
         <p>
           Sets the default maximum heap size settings for processes.
           The size is specified in words. The new <c>max_heap_size</c>
           effects only processes spawned efter the change has been made.
           <c>max_heap_size</c> can be set for individual processes using
           <seealso marker="#spawn_opt/4"><c>spawn_opt/2,3,4</c></seealso> or
-          <seealso marker="#process_flag_message_queue_data">
+          <seealso marker="#process_flag_max_heap_size">
           <c>process_flag/2</c></seealso>.</p>
         <p>Returns the old value of the flag.</p>
       </desc>
     </func>
 
     <func>
-      <name name="system_flag" arity="2" clause_i="9"/>
+      <name name="system_flag" arity="2" clause_i="9"
+	    anchor="system_flag_multi_scheduling"/>
       <fsummary>Set system flag multi_scheduling.</fsummary>
       <desc>
-        <p><marker id="system_flag_multi_scheduling"></marker>
+        <p>
           If multi-scheduling is enabled, more than one scheduler
           thread is used by the emulator. Multi-scheduling can be
           blocked in two different ways. Either all schedulers but
@@ -7078,12 +7251,13 @@ ok
     </func>
 
     <func>
-      <name name="system_flag" arity="2" clause_i="10"/>
+      <name name="system_flag" arity="2" clause_i="10"
+	    anchor="system_flag_scheduler_bind_type"/>
       <fsummary>Set system flag scheduler_bind_type.</fsummary>
       <type name="scheduler_bind_type"/>
       <desc>
         <warning>
-          <p><marker id="system_flag_scheduler_bind_type"></marker>
+          <p>
             <em>This argument is deprecated.</em>
             Instead of using this argument, use command-line argument
             <seealso marker="erts:erl#+sbt"><c>+sbt</c></seealso> in
@@ -7204,10 +7378,11 @@ ok
     </func>
 
     <func>
-      <name name="system_flag" arity="2" clause_i="11"/>
+      <name name="system_flag" arity="2" clause_i="11"
+	    anchor="system_flag_scheduler_wall_time"/>
       <fsummary>Set system flag scheduler_wall_time.</fsummary>
       <desc>
-        <p><marker id="system_flag_scheduler_wall_time"></marker>
+        <p>
           Turns on or off scheduler wall time measurements.</p>
         <p>For more information, see
           <seealso marker="#statistics_scheduler_wall_time">
@@ -7216,10 +7391,11 @@ ok
     </func>
 
     <func>
-      <name name="system_flag" arity="2" clause_i="12"/>
+      <name name="system_flag" arity="2" clause_i="12"
+	    anchor="system_flag_schedulers_online"/>
       <fsummary>Set system flag schedulers_online.</fsummary>
       <desc>
-        <p><marker id="system_flag_schedulers_online"></marker>
+        <p>
           Sets the number of schedulers online. Range is
           <c><![CDATA[1 <= SchedulersOnline <=
           erlang:system_info(schedulers)]]></c>.</p>
@@ -7258,10 +7434,11 @@ ok
     </func>
 
     <func>
-      <name name="system_flag" arity="2" clause_i="14"/>
+      <name name="system_flag" arity="2" clause_i="14"
+	    anchor="system_flag_time_offset"/>
       <fsummary>Finalize the time offset.</fsummary>
       <desc>
-        <p><marker id="system_flag_time_offset"></marker>
+        <p>
           Finalizes the <seealso marker="#time_offset/0">time offset</seealso>
           when <seealso marker="time_correction#Single_Time_Warp_Mode">single
           time warp mode</seealso> is used. If another time warp mode
@@ -7434,7 +7611,8 @@ ok
     </func>
 
     <func>
-      <name name="system_info" arity="1" clause_i="12"/>
+      <name name="system_info" arity="1" clause_i="12"
+	    anchor="system_info_cpu_topology"/>
       <name name="system_info" arity="1" clause_i="13"/>
       <fsummary>Information about the CPU topology of the system.</fsummary>
       <type name="cpu_topology"/>
@@ -7462,7 +7640,6 @@ ok
       </type_desc>
       <desc>
         <marker id="system_info_cpu_topology_tags"></marker>
-        <marker id="system_info_cpu_topology"></marker>
         <p>Returns various information about the CPU topology of
           the current system (emulator) as specified by
           <c><anno>Item</anno></c>:</p>
@@ -7910,15 +8087,6 @@ ok
               The return value will always be <c>false</c>, as the
               <c>elib_malloc</c> allocator has been removed.</p>
           </item>
-          <tag><marker id="system_info_eager_check_io"/>
-            <c>eager_check_io</c></tag>
-          <item>
-            <p>Returns the value of command-line flag
-              <seealso marker="erl#+secio"><c>+secio</c></seealso> in
-              <c>erl(1)</c>, which is either <c>true</c> or <c>false</c>.
-              For information about the different values, see the
-              documentation of the command-line flag.</p>
-          </item>
           <tag><c>ets_limit</c></tag>
           <item>
             <p>Returns the maximum number of ETS tables allowed. This
@@ -8021,9 +8189,7 @@ ok
             <taglist>
               <tag><c>disabled</c></tag>
               <item>
-                <p>The emulator has only one scheduler thread. The
-                  emulator does not have SMP support, or have been
-                  started with only one scheduler thread.</p>
+                <p>The emulator has been started with only one scheduler thread.</p>
               </item>
               <tag><c>blocked</c></tag>
               <item>
@@ -8386,8 +8552,7 @@ ok
           </item>
           <tag><c>smp_support</c></tag>
           <item>
-            <p>Returns <c>true</c> if the emulator has been compiled
-              with SMP support, otherwise <c>false</c> is returned.</p>
+            <p>Returns <c>true</c>.</p>
           </item>
           <tag><marker id="system_info_start_time"/><c>start_time</c></tag>
           <item>
@@ -8410,8 +8575,7 @@ ok
           </item>
           <tag><c>threads</c></tag>
           <item>
-            <p>Returns <c>true</c> if the emulator has been compiled
-              with thread support, otherwise <c>false</c> is returned.</p>
+            <p>Returns <c>true</c>.</p>
           </item>
           <tag><c>thread_pool_size</c></tag>
           <item>
@@ -10534,9 +10698,9 @@ true</pre>
           <c>receive after 1 -> ok end</c>, except that <c>yield()</c>
           is faster.</p>
         <warning>
-          <p>There is seldom or never any need to use this BIF,
-            especially in the SMP emulator, as other processes have a
-            chance to run in another scheduler thread anyway.
+          <p>There is seldom or never any need to use this BIF
+            as other processes have a chance to run in another scheduler
+            thread anyway.
             Using this BIF without a thorough grasp of how the scheduler
             works can cause performance degradation.</p>
         </warning>
diff --git a/erts/doc/src/erlc.xml b/erts/doc/src/erlc.xml
index 7355be488b..2214b76a51 100644
--- a/erts/doc/src/erlc.xml
+++ b/erts/doc/src/erlc.xml
@@ -143,6 +143,14 @@
         <p>Produces a Makefile rule to track header dependencies. The
           rule is sent to <c>stdout</c>. No object file is produced.</p>
       </item>
+
+      <tag><c>-MMD</c></tag>
+      <item>
+        <p>Generate dependencies as a side-effect. The object file
+	will be produced as normal. This option overrides the
+	option <c><![CDATA[-M]]></c>.</p>
+      </item>
+
       <tag><c>-MF &lt;Makefile&gt;</c></tag>
       <item>
         <p>As option <c><![CDATA[-M]]></c>, except that the
diff --git a/erts/doc/src/erts_alloc.xml b/erts/doc/src/erts_alloc.xml
index d3f725ef99..580780e73b 100644
--- a/erts/doc/src/erts_alloc.xml
+++ b/erts/doc/src/erts_alloc.xml
@@ -87,9 +87,9 @@
         the number of system calls made.</item>
     </taglist>
 
-    <p><c>sys_alloc</c> and <c>literal_alloc</c> are always enabled and
-      cannot be disabled. <c>exec_alloc</c> is only available if it is needed
-      and cannot be disabled. <c>mseg_alloc</c> is always enabled if it is
+    <p><c>sys_alloc</c>, <c>literal_alloc</c> and <c>temp_alloc</c> are always
+      enabled and cannot be disabled. <c>exec_alloc</c> is only available if it
+      is needed and cannot be disabled. <c>mseg_alloc</c> is always enabled if it is
       available and an allocator that uses it is enabled. All other
       allocators can be <seealso marker="#M_e">enabled or disabled</seealso>.
       By default all allocators are enabled.
diff --git a/erts/doc/src/notes.xml b/erts/doc/src/notes.xml
index 39dd90b8a0..e91e56e581 100644
--- a/erts/doc/src/notes.xml
+++ b/erts/doc/src/notes.xml
@@ -4147,8 +4147,7 @@
 	    <p>The previously introduced "eager check I/O" feature is
 	    now enabled by default.</p>
 	    <p>Eager check I/O can be disabled using the <c>erl</c>
-	    command line argument: <seealso
-	    marker="erl#+secio"><c>+secio false</c></seealso></p>
+	    command line argument: <c>+secio false</c></p>
 	    <p>Characteristics impact compared to previous
 	    default:</p> <list> <item>Lower latency and smoother
 	    management of externally triggered I/O operations.</item>
@@ -4929,8 +4928,7 @@
 	    prioritized to the same extent as when eager check I/O is
 	    disabled.</p>
 	    <p>Eager check I/O can be enabled using the <c>erl</c>
-	    command line argument: <seealso
-	    marker="erl#+secio"><c>+secio true</c></seealso></p>
+	    command line argument: <c>+secio true</c></p>
 	    <p>Characteristics impact when enabled:</p> <list>
 	    <item>Lower latency and smoother management of externally
 	    triggered I/O operations.</item> <item>A slightly reduced
diff --git a/erts/emulator/Makefile.in b/erts/emulator/Makefile.in
index 1916b97a89..15b65f1c71 100644
--- a/erts/emulator/Makefile.in
+++ b/erts/emulator/Makefile.in
@@ -28,10 +28,22 @@ HIPE_ENABLED=@HIPE_ENABLED@
 DTRACE_ENABLED=@DTRACE_ENABLED@
 DTRACE_ENABLED_2STEP=@DTRACE_ENABLED_2STEP@
 USE_VM_PROBES=@USE_VM_PROBES@
+FPE=@FPE@
 LIBS = @LIBS@
 Z_LIB=@Z_LIB@
 NO_INLINE_FUNCTIONS=false
-OPCODE_TABLES = $(ERL_TOP)/lib/compiler/src/genop.tab beam/ops.tab
+OPCODE_TABLES = $(ERL_TOP)/lib/compiler/src/genop.tab \
+beam/ops.tab \
+beam/macros.tab \
+beam/instrs.tab \
+beam/arith_instrs.tab \
+beam/bif_instrs.tab \
+beam/bs_instrs.tab \
+beam/float_instrs.tab \
+beam/map_instrs.tab \
+beam/msg_instrs.tab \
+beam/select_instrs.tab \
+beam/trace_instrs.tab
 
 DEBUG_CFLAGS = @DEBUG_CFLAGS@
 CONFIGURE_CFLAGS = @CFLAGS@
@@ -51,7 +63,27 @@ ARFLAGS=rc
 OMIT_OMIT_FP=no
 TYPE_LIBS=
 
-DIRTY_SCHEDULER_SUPPORT=@DIRTY_SCHEDULER_SUPPORT@
+PROFILE_COMPILER=@PROFILE_COMPILER@
+PROFILE_MARKER=
+ifeq ($(PROFILE),generate)
+PROFILE_MARKER=_pg
+else
+ifeq ($(PROFILE),use)
+PROFILE_MARKER=_pu
+endif
+endif
+
+ifeq ($(PROFILE_COMPILER), gcc)
+PROFILE_GENERATE=-fprofile-generate
+PROFILE_USE=-fprofile-use -fprofile-correction
+PROFILE_USE_DEPS=$(OBJDIR)/%_pu.gcda
+endif
+ifeq ($(PROFILE_COMPILER), clang)
+PROFILE_GENERATE=-fprofile-instr-generate
+PROFILE_USE=-fprofile-instr-use=$(OBJDIR)/default.profdata
+PROFILE_USE_DEPS=$(OBJDIR)/default.profdata
+endif
+
 DIRTY_SCHEDULER_TEST=@DIRTY_SCHEDULER_TEST@
 
 ifeq ($(TYPE),debug)
@@ -178,31 +210,10 @@ endif
 # NOTE: When adding a new type update ERL_BUILD_TYPE_MARKER in sys/unix/sys.c
 #
 
-FLAVOR=$(DEFAULT_FLAVOR)
-
-ifeq ($(FLAVOR),plain)
-
-DS_SUPPORT=no
-DS_TEST=no
-
-FLAVOR_MARKER=
-FLAVOR_FLAGS=
-ENABLE_ALLOC_TYPE_VARS += nofrag
-M4FLAGS +=
-
-else # FLAVOR
-
-# If flavor isn't one of the above, it *is* smp flavor...
 override FLAVOR=smp
 
 FLAVOR_MARKER=.smp
-FLAVOR_FLAGS=-DERTS_SMP
-ENABLE_ALLOC_TYPE_VARS += smp nofrag
-M4FLAGS += -DERTS_SMP=1
-ifeq ($(DIRTY_SCHEDULER_SUPPORT),yes)
-THR_DEFS += -DERTS_DIRTY_SCHEDULERS
-DS_SUPPORT=yes
-
+ENABLE_ALLOC_TYPE_VARS += nofrag
 ifeq ($(DIRTY_SCHEDULER_TEST),yes)
 DS_TEST=yes
 THR_DEFS += -DERTS_DIRTY_SCHEDULERS_TEST
@@ -210,13 +221,6 @@ else # DIRTY_SCHEDULER_TEST
 DS_TEST=no
 endif # DIRTY_SCHEDULER_TEST
 
-else # DIRTY_SCHEDULER_SUPPORT
-DS_SUPPORT=no
-DS_TEST=no
-endif # DIRTY_SCHEDULER_SUPPORT
-
-endif # FLAVOR
-
 TF_MARKER=$(TYPEMARKER)$(FLAVOR_MARKER)
 
 ifeq ($(TYPE)-@HAVE_VALGRIND@,valgrind-no)
@@ -235,18 +239,9 @@ ARCH=@ARCH@
 ultrasparcCFLAGS=-Wa,-xarch=v8plusa
 ARCHCFLAGS=$($(ARCH)CFLAGS)
 
-ifdef HIPE_ENABLED
-ifeq ($(OPSYS),linux)
-ppcBEAMLDFLAGS=-Wl,-m,elf32ppc
-ppc64BEAMLDFLAGS=-Wl,-m,elf64ppc,-T,hipe/elf64ppc.x
-endif
-ifeq ($(OPSYS),darwin)
-amd64BEAMLDFLAGS=-pagezero_size 0x10000000
-endif
-HIPEBEAMLDFLAGS=$($(ARCH)BEAMLDFLAGS)
-endif
+HIPEBEAMLDFLAGS=@HIPEBEAMLDFLAGS@
 
-ERTS_ENABLE_KERNEL_POLL=@ERTS_ENABLE_KERNEL_POLL@
+ERTS_BUILD_FALLBACK_POLL=@ERTS_BUILD_FALLBACK_POLL@
 
 #
 #
@@ -425,9 +420,20 @@ ifeq ($(TARGET), win32)
 EMULATOR_EXECUTABLE = beam$(TF_MARKER).dll
 else
 EMULATOR_EXECUTABLE = beam$(TF_MARKER)
+PROFILE_EXECUTABLE = beam.prof$(TF_MARKER)
 endif
 CS_EXECUTABLE = erl_child_setup$(TYPEMARKER)
 
+ifeq ($(PROFILE), generate)
+EMULATOR_EXECUTABLE = $(PROFILE_EXECUTABLE)
+ifeq ($(PROFILE_COMPILER), gcc)
+PROFILE_LDFLAGS = -fprofile-generate
+endif
+ifeq ($(PROFILE_COMPILER), clang)
+PROFILE_LDFLAGS = -fprofile-instr-generate
+endif
+endif
+
 # ----------------------------------------------------------------------
 
 ifeq ($(ERLANG_OSTYPE), unix)
@@ -483,7 +489,6 @@ ifeq ($(TARGET),win32)
 RELEASE_INCLUDES += sys/$(ERLANG_OSTYPE)/erl_win_dyn_driver.h
 endif
 
-
 .PHONY: release_spec
 ifdef VOID_EMULATOR
 release_spec:
@@ -548,10 +553,11 @@ DTRACE_HEADERS =
 endif
 
 ifdef HIPE_ENABLED
-OPCODE_TABLES += hipe/hipe_ops.tab
+OPCODE_TABLES += hipe/hipe_ops.tab hipe/hipe_instrs.tab
 endif
 
 $(TTF_DIR)/beam_cold.h \
+$(TTF_DIR)/beam_warm.h \
 $(TTF_DIR)/beam_hot.h \
 $(TTF_DIR)/beam_opcodes.c \
 $(TTF_DIR)/beam_opcodes.h \
@@ -561,8 +567,10 @@ $(TTF_DIR)/beam_tr_funcs.h \
 $(TTF_DIR)/OPCODES-GENERATED: $(OPCODE_TABLES) utils/beam_makeops
 	$(gen_verbose)LANG=C $(PERL) utils/beam_makeops \
 		-wordsize @EXTERNAL_WORD_SIZE@ \
+		-code-model @CODE_MODEL@ \
 		-outdir $(TTF_DIR) \
 		-DUSE_VM_PROBES=$(if $(USE_VM_PROBES),1,0) \
+		-DNO_FPE_SIGNALS=$(if $filter(unreliable,$(FPE)),1,0) \
 		-emulator $(OPCODE_TABLES) && echo $? >$(TTF_DIR)/OPCODES-GENERATED
 GENERATE += $(TTF_DIR)/OPCODES-GENERATED
 
@@ -599,7 +607,7 @@ $(HIPE_NBIF_FILES) \
 	: $(TTF_DIR)/TABLES-GENERATED
 $(TTF_DIR)/TABLES-GENERATED: $(ATOMS) $(DIRTY_BIFS) $(BIFS) utils/make_tables
 	$(gen_verbose)LANG=C $(PERL) utils/make_tables -src $(TTF_DIR) -include $(TTF_DIR)\
-		-ds $(DS_SUPPORT) -dst $(DS_TEST) -hipe $(HIPE) $(ATOMS) $(DIRTY_BIFS) $(BIFS) && echo $? >$(TTF_DIR)/TABLES-GENERATED
+		-dst $(DS_TEST) -hipe $(HIPE) $(ATOMS) $(DIRTY_BIFS) $(BIFS) && echo $? >$(TTF_DIR)/TABLES-GENERATED
 GENERATE += $(TTF_DIR)/TABLES-GENERATED
 
 $(TTF_DIR)/erl_alloc_types.h: beam/erl_alloc.types utils/make_alloc_types
@@ -626,6 +634,7 @@ GENERATE += $(TTF_DIR)/driver_tab.c
 PRELOAD_BEAM =		$(ERL_TOP)/erts/preloaded/ebin/otp_ring0.beam \
 			$(ERL_TOP)/erts/preloaded/ebin/erts_code_purger.beam \
 			$(ERL_TOP)/erts/preloaded/ebin/init.beam \
+			$(ERL_TOP)/erts/preloaded/ebin/prim_buffer.beam \
 			$(ERL_TOP)/erts/preloaded/ebin/prim_eval.beam \
 			$(ERL_TOP)/erts/preloaded/ebin/prim_inet.beam \
 			$(ERL_TOP)/erts/preloaded/ebin/prim_file.beam \
@@ -693,17 +702,66 @@ $(OBJDIR)/beams.$(RES_EXT): $(TARGET)/beams.rc
 
 endif
 
-ifneq ($(filter tile-%,$(TARGET)),)
-$(OBJDIR)/beam_emu.o: beam/beam_emu.c
-	$(V_CC) $(subst -O2, $(GEN_OPT_FLGS), $(CFLAGS)) \
-         $(INCLUDES) -c $< -o $@
-else
+# We disable the implicit rule of .S -> .o so that the verbose asm
+# generate is not used for compiling erts. This is only a problem on
+# old solaris make
+%.o : %.S
+
 # Usually the same as the default rule, but certain platforms (e.g. win32) mix
 # different compilers
 $(OBJDIR)/beam_emu.o: beam/beam_emu.c
 	$(V_EMU_CC) $(subst -O2, $(GEN_OPT_FLGS), $(CFLAGS)) $(INCLUDES) -c $< -o $@
+
+$(OBJDIR)/beam_emu.S: beam/beam_emu.c
+	$(V_EMU_CC) -S -fverbose-asm $(subst -O2, $(GEN_OPT_FLGS), $(CFLAGS)) $(INCLUDES) -c $< -o $@
+
+$(OBJDIR)/%_pg.o: beam/%.c
+	$(V_CC) $(PROFILE_GENERATE) $(subst -O2, $(GEN_OPT_FLGS), $(CFLAGS)) $(INCLUDES) -c $< -o $@
+$(OBJDIR)/%_pu.o: beam/%.c $(PROFILE_USE_DEPS)
+	$(V_CC) $(PROFILE_USE) $(subst -O2, $(GEN_OPT_FLGS), $(CFLAGS)) $(INCLUDES) -c $< -o $@
+
+$(OBJDIR)/%_pu.S: beam/%.c $(PROFILE_USE_DEPS)
+	$(V_CC) -S -fverbose-asm $(PROFILE_USE) $(subst -O2, $(GEN_OPT_FLGS), $(CFLAGS)) $(INCLUDES) -c $< -o $@
+
+$(OBJDIR)/PROFILE: $(BINDIR)/$(PROFILE_EXECUTABLE)
+	$(V_at)echo " PROFILE ${PROFILE_EXECUTABLE}"
+	$(V_at)rm -f $(OBJDIR)/erl*.profraw
+	$(V_at)set -e; LLVM_PROFILE_FILE="$(OBJDIR)/erlc-%m.profraw" \
+          ERL_FLAGS="-emu_type prof${TYPEMARKER} +S 1" $(ERLC) -DPGO \
+	  -o $(OBJDIR) test/estone_SUITE.erl > $(OBJDIR)/PROFILE_LOG
+	$(V_at)set -e; LLVM_PROFILE_FILE="$(OBJDIR)/erl-%m.profraw" \
+	  ERL_FLAGS="-emu_type prof${TYPEMARKER} +S 1" $(ERL) -pa $(OBJDIR) \
+	  -noshell -s estone_SUITE pgo -s init stop >> $(OBJDIR)/PROFILE_LOG
+	$(V_at)touch $@
+
+.SECONDARY: $(patsubst %.o,%_pu.gcda,$(PROFILE_OBJS))
+
+$(OBJDIR)/%_pu.gcda: $(OBJDIR)/PROFILE
+	$(V_at)mv $(OBJDIR)/$*_pg.gcda $@
+	$(V_at)touch $@
+
+$(OBJDIR)/default.profdata: $(OBJDIR)/PROFILE
+	$(V_LLVM_PROFDATA) merge -output $@ $(OBJDIR)/*.profraw
+
+ifeq ($(ERTS_BUILD_FALLBACK_POLL),yes)
+# Have to treat erl_poll differently as the same .c file is used
+# twice for kernel poll builds.
+$(OBJDIR)/erl_poll.o: sys/common/erl_poll.c
+	$(V_CC) -DERTS_KERNEL_POLL_VERSION $(subst -O2, $(GEN_OPT_FLGS), $(CFLAGS)) $(INCLUDES) -c $< -o $@
+
+# Do a copy in order to make debuggers less confused
+$(TTF_DIR)/erl_poll.flbk.c: sys/common/erl_poll.c
+	$(V_at) cp $< $@
+	@touch $@
+
+$(OBJDIR)/erl_poll.flbk.o: $(TTF_DIR)/erl_poll.flbk.c
+	$(V_CC) -DERTS_NO_KERNEL_POLL_VERSION $(subst -O2, $(GEN_OPT_FLGS), $(CFLAGS)) $(INCLUDES) -c $< -o $@
 endif
 
+
+# ----------------------------------------------------------------------
+# General targets
+#
 $(OBJDIR)/%.o: beam/%.c
 	$(V_CC) $(subst -O2, $(GEN_OPT_FLGS), $(CFLAGS)) $(INCLUDES) -c $< -o $@
 
@@ -728,6 +786,9 @@ $(OBJDIR)/%.o: drivers/$(ERLANG_OSTYPE)/%.c
 $(OBJDIR)/%.o: nifs/common/%.c
 	$(V_CC) $(CFLAGS) -DLIBSCTP=$(LIBSCTP) $(INCLUDES) -Inifs/common -Inifs/$(ERLANG_OSTYPE) -c $< -o $@
 
+$(OBJDIR)/%.o: nifs/$(ERLANG_OSTYPE)/%.c
+	$(V_CC) $(CFLAGS) $(INCLUDES) -Inifs/common -Inifs/$(ERLANG_OSTYPE) -I../etc/$(ERLANG_OSTYPE) -c $< -o $@
+
 # ----------------------------------------------------------------------
 # Specials
 #
@@ -737,12 +798,6 @@ $(BINDIR)/$(CS_EXECUTABLE): $(TTF_DIR)/GENERATED $(PRELOAD_SRC) $(CS_OBJ) $(ERTS
 	$(ld_verbose)$(CS_PURIFY) $(LD) $(CS_LDFLAGS) -o $(BINDIR)/$(CS_EXECUTABLE) \
                $(CS_CFLAGS) $(COMMON_INCLUDES) $(CS_OBJ) $(CS_LIBS)
 
-$(OBJDIR)/%.kp.o: sys/common/%.c
-	$(V_CC) -DERTS_KERNEL_POLL_VERSION $(subst -O2, $(GEN_OPT_FLGS), $(CFLAGS)) $(INCLUDES) -c $< -o $@
-
-$(OBJDIR)/%.nkp.o: sys/common/%.c
-	$(V_CC) -DERTS_NO_KERNEL_POLL_VERSION $(subst -O2, $(GEN_OPT_FLGS), $(CFLAGS)) $(INCLUDES) -c $< -o $@
-
 ifeq ($(GCC),yes)
 
 $(OBJDIR)/erl_goodfit_alloc.o: beam/erl_goodfit_alloc.c
@@ -764,15 +819,16 @@ $(ERL_TOP)/lib/%.beam:
 
 INIT_OBJS = $(OBJDIR)/erl_main.o	$(PRELOAD_OBJ)
 
+PROFILE_OBJS = $(OBJDIR)/beam_emu.o	$(OBJDIR)/erl_process.o
+
 EMU_OBJS = \
-	$(OBJDIR)/beam_emu.o		$(OBJDIR)/beam_opcodes.o \
+	$(OBJDIR)/beam_opcodes.o \
 	$(OBJDIR)/beam_load.o		$(OBJDIR)/beam_bif_load.o \
 	$(OBJDIR)/beam_debug.o		$(OBJDIR)/beam_bp.o \
-	$(OBJDIR)/beam_catches.o \
-	$(OBJDIR)/code_ix.o \
+	$(OBJDIR)/beam_catches.o 	$(OBJDIR)/code_ix.o \
 	$(OBJDIR)/beam_ranges.o
 
-RUN_OBJS = \
+RUN_OBJS += \
 	$(OBJDIR)/erl_alloc.o		$(OBJDIR)/erl_mtrace.o \
 	$(OBJDIR)/erl_alloc_util.o	$(OBJDIR)/erl_goodfit_alloc.o \
 	$(OBJDIR)/erl_bestfit_alloc.o	$(OBJDIR)/erl_afit_alloc.o \
@@ -788,7 +844,7 @@ RUN_OBJS = \
 	$(OBJDIR)/utils.o		$(OBJDIR)/bif.o \
 	$(OBJDIR)/io.o 			$(OBJDIR)/erl_printf_term.o\
 	$(OBJDIR)/erl_debug.o		$(OBJDIR)/erl_md5.o \
-	$(OBJDIR)/erl_message.o		$(OBJDIR)/erl_process.o \
+	$(OBJDIR)/erl_message.o		 \
 	$(OBJDIR)/erl_process_dict.o	$(OBJDIR)/erl_process_lock.o \
 	$(OBJDIR)/erl_port_task.o	$(OBJDIR)/erl_arith.o \
 	$(OBJDIR)/time.o		$(OBJDIR)/erl_time_sup.o  \
@@ -821,17 +877,17 @@ RUN_OBJS = \
 LTTNG_OBJS = $(OBJDIR)/erlang_lttng.o
 NIF_OBJS = \
 	   $(OBJDIR)/erl_tracer_nif.o \
+	   $(OBJDIR)/prim_buffer_nif.o \
+	   $(OBJDIR)/prim_file_nif.o \
 	   $(OBJDIR)/zlib_nif.o
 
 ifeq ($(TARGET),win32)
 DRV_OBJS = \
 	$(OBJDIR)/registry_drv.o \
-	$(OBJDIR)/efile_drv.o \
 	$(OBJDIR)/inet_drv.o \
 	$(OBJDIR)/ram_file_drv.o \
 	$(OBJDIR)/ttsl_drv.o
 OS_OBJS = \
-	$(OBJDIR)/win_efile.o \
 	$(OBJDIR)/win_con.o \
 	$(OBJDIR)/dll_sys.o \
 	$(OBJDIR)/driver_tab.o \
@@ -840,7 +896,8 @@ OS_OBJS = \
 	$(OBJDIR)/sys_time.o \
 	$(OBJDIR)/sys_interrupt.o \
 	$(OBJDIR)/sys_env.o \
-	$(OBJDIR)/dosmap.o
+	$(OBJDIR)/dosmap.o \
+	$(OBJDIR)/win_prim_file.o
 
 else
 OS_OBJS = \
@@ -848,14 +905,13 @@ OS_OBJS = \
 	$(OBJDIR)/sys_drivers.o \
 	$(OBJDIR)/sys_uds.o \
 	$(OBJDIR)/driver_tab.o \
-	$(OBJDIR)/unix_efile.o \
+	$(OBJDIR)/elib_memmove.o \
 	$(OBJDIR)/gzio.o \
-	$(OBJDIR)/elib_memmove.o
+	$(OBJDIR)/unix_prim_file.o
 
 	OS_OBJS += $(OBJDIR)/sys_float.o \
                    $(OBJDIR)/sys_time.o
 DRV_OBJS = \
-	$(OBJDIR)/efile_drv.o \
 	$(OBJDIR)/inet_drv.o \
 	$(OBJDIR)/ram_file_drv.o \
 	$(OBJDIR)/ttsl_drv.o
@@ -885,23 +941,19 @@ $(STATIC_NIF_LIBS) $(STATIC_DRIVER_LIBS):
 	echo "=== Leaving lib after making static libs"
 endif
 
-ifeq ($(ERTS_ENABLE_KERNEL_POLL),yes)
-OS_OBJS += 	$(OBJDIR)/erl_poll.kp.o \
-		$(OBJDIR)/erl_check_io.kp.o \
-		$(OBJDIR)/erl_poll.nkp.o \
-		$(OBJDIR)/erl_check_io.nkp.o
-else
 OS_OBJS +=	$(OBJDIR)/erl_poll.o \
-		$(OBJDIR)/erl_check_io.o
-endif
-
-OS_OBJS +=	$(OBJDIR)/erl_mseg.o \
+		$(OBJDIR)/erl_check_io.o \
+		$(OBJDIR)/erl_mseg.o \
 		$(OBJDIR)/erl_mmap.o \
 		$(OBJDIR)/erl_$(ERLANG_OSTYPE)_sys_ddll.o \
 		$(OBJDIR)/erl_mtrace_sys_wrap.o \
 		$(OBJDIR)/erl_sys_common_misc.o \
 		$(OBJDIR)/erl_os_monotonic_time_extender.o
 
+ifeq ($(ERTS_BUILD_FALLBACK_POLL),yes)
+OS_OBJS += 	$(OBJDIR)/erl_poll.flbk.o
+endif
+
 HIPE_ARCH64_OBJS=$(OBJDIR)/hipe_bif64.o
 
 HIPE_x86_OS_OBJS=$(HIPE_x86_$(OPSYS)_OBJS)
@@ -930,21 +982,23 @@ ifdef HIPE_ENABLED
 EXTRA_BASE_OBJS += $(HIPE_OBJS)
 endif
 
-BASE_OBJS = $(EMU_OBJS) $(RUN_OBJS) $(OS_OBJS) $(EXTRA_BASE_OBJS) $(LTTNG_OBJS)
+BASE_OBJS = $(EMU_OBJS) $(RUN_OBJS) $(OS_OBJS) $(EXTRA_BASE_OBJS) \
+	$(LTTNG_OBJS) $(DRV_OBJS) $(NIF_OBJS)
+
+PROF_OBJS = $(patsubst %.o,%$(PROFILE_MARKER).o,$(PROFILE_OBJS)) $(BASE_OBJS)
 
-before_DTrace_OBJS =	$(BASE_OBJS) $(DRV_OBJS) $(NIF_OBJS)
+OBJS = $(PROF_OBJS)
 
-DTRACE_OBJS =
 ifdef DTRACE_ENABLED_2STEP
-DTRACE_OBJS = $(OBJDIR)/erlang_dtrace.o
-$(OBJDIR)/erlang_dtrace.o: $(before_DTrace_OBJS) $(TARGET)/erlang_dtrace.h
+# The $(PROFILE_MARKER) is placed in the object file name in order to
+# make sure we re-compile with the new object files for the profiled emulator
+OBJS += $(OBJDIR)/erlang$(PROFILE_MARKER)_dtrace.o
+$(OBJDIR)/erlang$(PROFILE_MARKER)_dtrace.o: $(PROF_OBJS) $(TARGET)/erlang_dtrace.h
 	dtrace -G -C -Ibeam \
 	  -s beam/erlang_dtrace.d \
-	  -o $@ $(before_DTrace_OBJS)
+	  -o $@ $(PROF_OBJS)
 endif
 
-OBJS = $(before_DTrace_OBJS) $(DTRACE_OBJS)
-
 $(INIT_OBJS): $(TTF_DIR)/GENERATED
 $(OBJS): $(TTF_DIR)/GENERATED
 
@@ -1036,8 +1090,8 @@ $(BINDIR)/$(EMULATOR_EXECUTABLE): $(INIT_OBJS) $(OBJS) $(DEPLIBS)
 
 else
 $(BINDIR)/$(EMULATOR_EXECUTABLE): $(INIT_OBJS) $(OBJS) $(DEPLIBS)
-	$(ld_verbose)$(PURIFY) $(LD) -o $(BINDIR)/$(EMULATOR_EXECUTABLE) \
-	$(HIPEBEAMLDFLAGS) $(LDFLAGS) $(DEXPORT) $(INIT_OBJS) $(OBJS) \
+	$(ld_verbose)$(PURIFY) $(LD) -o $@ \
+	$(HIPEBEAMLDFLAGS) $(PROFILE_LDFLAGS) $(LDFLAGS) $(DEXPORT) $(INIT_OBJS) $(OBJS) \
 	$(STATIC_NIF_LIBS) $(STATIC_DRIVER_LIBS) $(LIBS)
 
 endif
@@ -1056,8 +1110,7 @@ SED_REPL_O=s|^\([^:]*:\)|$$(OBJDIR)/\1|g
 SED_REPL_O_ZLIB=s|^\([^:]*:\)|$$(ZLIB_OBJDIR)/\1|g
 SED_REPL_TTF_DIR=s|$(TTF_DIR)/|$$(TTF_DIR)/|g
 SED_REPL_ERL_TOP=s|\([ 	]\)$(ERL_TOP)/|\1$$(ERL_TOP)/|g;s|^$(ERL_TOP)/|$$(ERL_TOP)/|g
-SED_REPL_POLL=s|$$(OBJDIR)/erl_poll.o|$$(OBJDIR)/erl_poll.kp.o $$(OBJDIR)/erl_poll.nkp.o|g
-SED_REPL_CHK_IO=s|$$(OBJDIR)/erl_check_io.o|$$(OBJDIR)/erl_check_io.kp.o $$(OBJDIR)/erl_check_io.nkp.o|g
+SED_REPL_POLL=s|$$(OBJDIR)/erl_poll.o|$$(OBJDIR)/erl_poll.o $$(OBJDIR)/erl_poll.flbk.o|g
 SED_REPL_TTF_COMP_FLAGS=s|\([^/]\)erl_compile_flags\.h|\1$$(TTF_DIR)/erl_compile_flags\.h|g
 
 ifeq ($(TARGET),win32)
@@ -1067,8 +1120,8 @@ else
 SED_PREFIX=
 endif
 
-ifeq ($(ERTS_ENABLE_KERNEL_POLL),yes)
-SED_SUFFIX=;$(SED_REPL_POLL);$(SED_REPL_CHK_IO)
+ifeq ($(ERTS_BUILD_FALLBACK_POLL),yes)
+SED_SUFFIX=;$(SED_REPL_POLL)
 else
 SED_SUFFIX=
 endif
@@ -1086,6 +1139,7 @@ BEAM_SRC=$(wildcard beam/*.c)
 DRV_COMMON_SRC=$(wildcard drivers/common/*.c)
 DRV_OSTYPE_SRC=$(wildcard drivers/$(ERLANG_OSTYPE)/*.c)
 NIF_COMMON_SRC=$(wildcard nifs/common/*.c)
+NIF_OSTYPE_SRC=$(wildcard nifs/$(ERLANG_OSTYPE)/*.c)
 ALL_SYS_SRC=$(wildcard sys/$(ERLANG_OSTYPE)/*.c) $(wildcard sys/common/*.c)
 # We use $(shell ls) here instead of wildcard as $(wildcard ) resolved at
 # loadtime of the makefile and at that time these files are not generated yet.
@@ -1098,7 +1152,10 @@ ifeq ($(TARGET),win32)
 
 #DEP_CC=$(EMU_CC)
 DEP_CC=$(CC)
-DEP_FLAGS=-MM  $(subst -O2,,$(CFLAGS)) $(INCLUDES) -I../etc/win32 -Idrivers/common -Idrivers/$(ERLANG_OSTYPE)
+DEP_FLAGS=-MM  $(subst -O2,,$(CFLAGS)) $(INCLUDES) -I../etc/win32 \
+	-Idrivers/common -Idrivers/$(ERLANG_OSTYPE) \
+	-Inifs/common -Inifs/$(ERLANG_OSTYPE)
+
 # ifeq (@MIXED_CYGWIN_VC@,yes)
 # VC++ used for compiling. If __GNUC__ is defined we will include
 # other headers then when compiling which will result in faulty
@@ -1118,10 +1175,16 @@ MG_FLAG=-MG
 endif
 
 DEP_CC=$(CC)
-DEP_FLAGS=-MM $(MG_FLAG) $(CFLAGS) $(INCLUDES) -Inifs/common -Idrivers/common -Idrivers/$(ERLANG_OSTYPE)
+DEP_FLAGS=-MM $(MG_FLAG) $(CFLAGS) $(INCLUDES) \
+	-Idrivers/common -Idrivers/$(ERLANG_OSTYPE) \
+	-Inifs/common -Inifs/$(ERLANG_OSTYPE)
 SYS_SRC=$(ALL_SYS_SRC)
 endif
 
+.PHONY: check_emu_registers
+check_emu_registers: $(OBJDIR)/beam_emu$(PROFILE_MARKER).S
+	utils/beam_emu_vars -vars 'c_p E HTOP FCALLS I reg' $^
+
 .PHONY: $(TARGET)/gen_git_version.mk
 $(TARGET)/gen_git_version.mk:
 # We touch beam/erl_bif.info.c if we regenerated the git version to force a
@@ -1145,6 +1208,8 @@ $(TTF_DIR)/depend.mk: $(TTF_DIR)/GENERATED $(PRELOAD_SRC)
 		| $(SED_DEPEND) >> $(TTF_DIR)/depend.mk
 	$(V_at)$(DEP_CC) $(DEP_FLAGS) $(NIF_COMMON_SRC) \
 		| $(SED_DEPEND) >> $(TTF_DIR)/depend.mk
+	$(V_at)$(DEP_CC) $(DEP_FLAGS) -I../etc/$(ERLANG_OSTYPE) $(NIF_OSTYPE_SRC) \
+		| $(SED_DEPEND) >> $(TTF_DIR)/depend.mk
 	$(V_at)$(DEP_CC) $(DEP_FLAGS) $(SYS_SRC) \
 		| $(SED_DEPEND) >> $(TTF_DIR)/depend.mk
 	$(V_at)$(DEP_CC) $(DEP_FLAGS) $(TARGET_SRC) \
diff --git a/erts/emulator/beam/arith_instrs.tab b/erts/emulator/beam/arith_instrs.tab
new file mode 100644
index 0000000000..b828e86788
--- /dev/null
+++ b/erts/emulator/beam/arith_instrs.tab
@@ -0,0 +1,396 @@
+// -*- c -*-
+//
+// %CopyrightBegin%
+//
+// Copyright Ericsson AB 2017. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// %CopyrightEnd%
+//
+
+OUTLINED_ARITH_2(Fail, Live, Name, BIF, Op1, Op2, Dst) {
+    Eterm result;
+    Uint live = $Live;
+    HEAVY_SWAPOUT;
+    reg[live] = $Op1;
+    reg[live+1] = $Op2;
+    result = erts_gc_$Name (c_p, reg, live);
+    HEAVY_SWAPIN;
+    ERTS_HOLE_CHECK(c_p);
+    if (ERTS_LIKELY(is_value(result))) {
+        $REFRESH_GEN_DEST();
+        $Dst = result;
+        $NEXT0();
+    }
+    $BIF_ERROR_ARITY_2($Fail, $BIF, reg[live], reg[live+1]);
+}
+
+
+i_plus := plus.fetch.execute;
+
+plus.head() {
+    Eterm PlusOp1, PlusOp2;
+}
+
+plus.fetch(Op1, Op2) {
+    PlusOp1 = $Op1;
+    PlusOp2 = $Op2;
+}
+
+plus.execute(Fail, Live, Dst) {
+    if (ERTS_LIKELY(is_both_small(PlusOp1, PlusOp2))) {
+        Sint i = signed_val(PlusOp1) + signed_val(PlusOp2);
+        if (ERTS_LIKELY(IS_SSMALL(i))) {
+            $Dst = make_small(i);
+            $NEXT0();
+        }
+    }
+    $OUTLINED_ARITH_2($Fail, $Live, mixed_plus, BIF_splus_2, PlusOp1, PlusOp2, $Dst);
+}
+
+i_minus := minus.fetch.execute;
+
+minus.head() {
+    Eterm MinusOp1, MinusOp2;
+}
+
+minus.fetch(Op1, Op2) {
+    MinusOp1 = $Op1;
+    MinusOp2 = $Op2;
+}
+
+minus.execute(Fail, Live, Dst) {
+    if (ERTS_LIKELY(is_both_small(MinusOp1, MinusOp2))) {
+        Sint i = signed_val(MinusOp1) - signed_val(MinusOp2);
+        if (ERTS_LIKELY(IS_SSMALL(i))) {
+            $Dst = make_small(i);
+            $NEXT0();
+        }
+    }
+    $OUTLINED_ARITH_2($Fail, $Live, mixed_minus, BIF_sminus_2, MinusOp1, MinusOp2, $Dst);
+}
+
+i_increment := increment.fetch.execute;
+
+increment.head() {
+    Eterm increment_reg_val;
+}
+
+increment.fetch(Src) {
+    increment_reg_val = $Src;
+}
+
+increment.execute(IncrementVal, Live, Dst) {
+    Eterm increment_val = $IncrementVal;
+    Uint live;
+    Eterm result;
+
+    if (ERTS_LIKELY(is_small(increment_reg_val))) {
+        Sint i = signed_val(increment_reg_val) + increment_val;
+        if (ERTS_LIKELY(IS_SSMALL(i))) {
+            $Dst = make_small(i);
+            $NEXT0();
+        }
+    }
+    live = $Live;
+    HEAVY_SWAPOUT;
+    reg[live] = increment_reg_val;
+    reg[live+1] = make_small(increment_val);
+    result = erts_gc_mixed_plus(c_p, reg, live);
+    HEAVY_SWAPIN;
+    ERTS_HOLE_CHECK(c_p);
+    if (ERTS_LIKELY(is_value(result))) {
+        $REFRESH_GEN_DEST();
+        $Dst = result;
+        $NEXT0();
+    }
+    ASSERT(c_p->freason != BADMATCH || is_value(c_p->fvalue));
+    goto find_func_info;
+}
+
+i_times(Fail, Live, Op1, Op2, Dst) {
+    Eterm op1 = $Op1;
+    Eterm op2 = $Op2;
+    $OUTLINED_ARITH_2($Fail, $Live, mixed_times, BIF_stimes_2, op1, op2, $Dst);
+}
+
+i_m_div(Fail, Live, Op1, Op2, Dst) {
+    Eterm op1 = $Op1;
+    Eterm op2 = $Op2;
+    $OUTLINED_ARITH_2($Fail, $Live, mixed_div, BIF_div_2, op1, op2, $Dst);
+}
+
+i_int_div(Fail, Live, Op1, Op2, Dst) {
+    Eterm op1 = $Op1;
+    Eterm op2 = $Op2;
+    if (ERTS_UNLIKELY(op2 == SMALL_ZERO)) {
+        c_p->freason = BADARITH;
+        $BIF_ERROR_ARITY_2($Fail, BIF_intdiv_2, op1, op2);
+    } else if (ERTS_LIKELY(is_both_small(op1, op2))) {
+        Sint ires = signed_val(op1) / signed_val(op2);
+        if (ERTS_LIKELY(IS_SSMALL(ires))) {
+            $Dst = make_small(ires);
+            $NEXT0();
+        }
+    }
+    $OUTLINED_ARITH_2($Fail, $Live, int_div, BIF_intdiv_2, op1, op2, $Dst);
+}
+
+i_rem := rem.fetch.execute;
+
+rem.head() {
+     Eterm RemOp1, RemOp2;
+}
+
+rem.fetch(Src1, Src2) {
+    RemOp1 = $Src1;
+    RemOp2 = $Src2;
+}
+
+rem.execute(Fail, Live, Dst) {
+    if (ERTS_UNLIKELY(RemOp2 == SMALL_ZERO)) {
+        c_p->freason = BADARITH;
+        $BIF_ERROR_ARITY_2($Fail, BIF_rem_2, RemOp1, RemOp2);
+    } else if (ERTS_LIKELY(is_both_small(RemOp1, RemOp2))) {
+        $Dst = make_small(signed_val(RemOp1) % signed_val(RemOp2));
+        $NEXT0();
+    } else {
+        $OUTLINED_ARITH_2($Fail, $Live, int_rem, BIF_rem_2, RemOp1, RemOp2, $Dst);
+    }
+}
+
+i_band := band.fetch.execute;
+
+band.head() {
+    Eterm BandOp1, BandOp2;
+}
+
+band.fetch(Src1, Src2) {
+    BandOp1 = $Src1;
+    BandOp2 = $Src2;
+}
+
+band.execute(Fail, Live, Dst) {
+    if (ERTS_LIKELY(is_both_small(BandOp1, BandOp2))) {
+        /*
+         * No need to untag -- TAG & TAG == TAG.
+         */
+        $Dst = BandOp1 & BandOp2;
+        $NEXT0();
+    }
+    $OUTLINED_ARITH_2($Fail, $Live, band, BIF_band_2, BandOp1, BandOp2, $Dst);
+}
+
+i_bor(Fail, Live, Src1, Src2, Dst) {
+    if (ERTS_LIKELY(is_both_small($Src1, $Src2))) {
+        /*
+         * No need to untag -- TAG | TAG == TAG.
+         */
+        $Dst = $Src1 | $Src2;
+        $NEXT0();
+    }
+    $OUTLINED_ARITH_2($Fail, $Live, bor, BIF_bor_2, $Src1, $Src2, $Dst);
+}
+
+i_bxor(Fail, Live, Src1, Src2, Dst) {
+    if (ERTS_LIKELY(is_both_small($Src1, $Src2))) {
+        /*
+         * TAG ^ TAG == 0.
+         *
+         * Therefore, we perform the XOR operation on the tagged values,
+         * and OR in the tag bits.
+         */
+        $Dst = ($Src1 ^ $Src2) | make_small(0);
+        $NEXT0();
+    }
+    $OUTLINED_ARITH_2($Fail, $Live, bxor, BIF_bxor_2, $Src1, $Src2, $Dst);
+}
+
+i_bsl := shift.setup_bsl.execute;
+i_bsr := shift.setup_bsr.execute;
+
+shift.head() {
+    Eterm Op1, Op2;
+    Sint shift_left_count;
+}
+
+shift.setup_bsr(Src1, Src2) {
+    Op1 = $Src1;
+    Op2 = $Src2;
+    shift_left_count = 0;
+    if (ERTS_LIKELY(is_small(Op2))) {
+        shift_left_count = -signed_val(Op2);
+    } else if (is_big(Op2)) {
+        /*
+         * N bsr NegativeBigNum == N bsl MAX_SMALL
+         * N bsr PositiveBigNum == N bsl MIN_SMALL
+         */
+        shift_left_count = make_small(bignum_header_is_neg(*big_val(Op2)) ?
+                                      MAX_SMALL : MIN_SMALL);
+    }
+}
+
+shift.setup_bsl(Src1, Src2) {
+    Op1 = $Src1;
+    Op2 = $Src2;
+    shift_left_count = 0;
+    if (ERTS_LIKELY(is_small(Op2))) {
+        shift_left_count = signed_val(Op2);
+    } else if (is_big(Op2)) {
+        if (bignum_header_is_neg(*big_val(Op2))) {
+            /*
+             * N bsl NegativeBigNum is either 0 or -1, depending on
+             * the sign of N. Since we don't believe this case
+             * is common, do the calculation with the minimum
+             * amount of code.
+             */
+            shift_left_count = MIN_SMALL;
+        } else if (is_integer(Op1)) {
+            /*
+             * N bsl PositiveBigNum is too large to represent.
+             */
+            shift_left_count = MAX_SMALL;
+        }
+    }
+}
+
+shift.execute(Fail, Live, Dst) {
+    Uint big_words_needed;
+
+    if (ERTS_LIKELY(is_small(Op1))) {
+        Sint int_res = signed_val(Op1);
+        if (ERTS_UNLIKELY(shift_left_count == 0 || int_res == 0)) {
+            if (ERTS_UNLIKELY(is_not_integer(Op2))) {
+                goto shift_error;
+            }
+            if (int_res == 0) {
+                $Dst = Op1;
+                $NEXT0();
+            }
+        } else if (shift_left_count < 0)  { /* Right shift */
+            Eterm bsr_res;
+            shift_left_count = -shift_left_count;
+            if (shift_left_count >= SMALL_BITS-1) {
+                bsr_res = (int_res < 0) ? SMALL_MINUS_ONE : SMALL_ZERO;
+            } else {
+                bsr_res = make_small(int_res >> shift_left_count);
+            }
+            $Dst = bsr_res;
+            $NEXT0();
+        } else if (shift_left_count < SMALL_BITS-1) { /* Left shift */
+            if ((int_res > 0 &&
+                 ((~(Uint)0 << ((SMALL_BITS-1)-shift_left_count)) & int_res) == 0) ||
+                ((~(Uint)0 << ((SMALL_BITS-1)-shift_left_count)) & ~int_res) == 0) {
+                $Dst = make_small(int_res << shift_left_count);
+                $NEXT0();
+            }
+        }
+        big_words_needed = 1;   /* big_size(small_to_big(Op1)) */
+        goto big_shift;
+    } else if (is_big(Op1)) {
+        if (shift_left_count == 0) {
+            if (is_not_integer(Op2)) {
+                goto shift_error;
+            }
+            $Dst = Op1;
+            $NEXT0();
+        }
+        big_words_needed = big_size(Op1);
+
+    big_shift:
+        if (shift_left_count > 0) {	/* Left shift. */
+            big_words_needed += (shift_left_count / D_EXP);
+        } else {	/* Right shift. */
+            if (big_words_needed <= (-shift_left_count / D_EXP)) {
+                big_words_needed = 3;       /* ??? */
+            } else {
+                big_words_needed -= (-shift_left_count / D_EXP);
+            }
+        }
+        {
+            Eterm tmp_big[2];
+            Sint big_need_size = BIG_NEED_SIZE(big_words_needed+1);
+
+            /*
+             * Slightly conservative check the size to avoid
+             * allocating huge amounts of memory for bignums that
+             * clearly would overflow the arity in the header
+             * word.
+             */
+            if (big_need_size-8 > BIG_ARITY_MAX) {
+                $SYSTEM_LIMIT($Fail);
+            }
+            $GC_TEST_PRESERVE(big_need_size+1, $Live, Op1);
+            if (is_small(Op1)) {
+                Op1 = small_to_big(signed_val(Op1), tmp_big);
+            }
+            Op1 = big_lshift(Op1, shift_left_count, HTOP);
+            if (is_big(Op1)) {
+                HTOP += bignum_header_arity(*HTOP) + 1;
+            }
+            HEAP_SPACE_VERIFIED(0);
+            if (ERTS_UNLIKELY(is_nil(Op1))) {
+                /*
+                 * This result must have been only slighty larger
+                 * than allowed since it wasn't caught by the
+                 * previous test.
+                 */
+                $SYSTEM_LIMIT($Fail);
+            }
+            ERTS_HOLE_CHECK(c_p);
+            $REFRESH_GEN_DEST();
+            $Dst = Op1;
+            $NEXT0();
+        }
+    }
+
+    /*
+     * One or more non-integer arguments.
+     */
+ shift_error:
+    c_p->freason = BADARITH;
+    if ($Fail) {
+        $FAIL($Fail);
+    } else {
+        reg[0] = Op1;
+        reg[1] = Op2;
+        SWAPOUT;
+        if (IsOpCode(I[0], i_bsl_ssjtd)) {
+            I = handle_error(c_p, I, reg, &bif_export[BIF_bsl_2]->info.mfa);
+        } else {
+            ASSERT(IsOpCode(I[0], i_bsr_ssjtd));
+            I = handle_error(c_p, I, reg, &bif_export[BIF_bsr_2]->info.mfa);
+        }
+        goto post_error_handling;
+    }
+}
+
+i_int_bnot(Fail, Src, Live, Dst) {
+    Eterm bnot_val = $Src;
+    if (ERTS_LIKELY(is_small(bnot_val))) {
+        bnot_val = make_small(~signed_val(bnot_val));
+    } else {
+        Uint live = $Live;
+        HEAVY_SWAPOUT;
+        reg[live] = bnot_val;
+        bnot_val = erts_gc_bnot(c_p, reg, live);
+        HEAVY_SWAPIN;
+        ERTS_HOLE_CHECK(c_p);
+        if (ERTS_UNLIKELY(is_nil(bnot_val))) {
+            $BIF_ERROR_ARITY_1($Fail, BIF_bnot_1, reg[live]);
+        }
+        $REFRESH_GEN_DEST();
+    }
+    $Dst = bnot_val;
+}
diff --git a/erts/emulator/beam/atom.c b/erts/emulator/beam/atom.c
index 38e02c386f..bbe1cb3e11 100644
--- a/erts/emulator/beam/atom.c
+++ b/erts/emulator/beam/atom.c
@@ -34,20 +34,18 @@
 
 IndexTable erts_atom_table;	/* The index table */
 
-#include "erl_smp.h"
+static erts_rwmtx_t atom_table_lock;
 
-static erts_smp_rwmtx_t atom_table_lock;
-
-#define atom_read_lock()	erts_smp_rwmtx_rlock(&atom_table_lock)
-#define atom_read_unlock()	erts_smp_rwmtx_runlock(&atom_table_lock)
-#define atom_write_lock()	erts_smp_rwmtx_rwlock(&atom_table_lock)
-#define atom_write_unlock()	erts_smp_rwmtx_rwunlock(&atom_table_lock)
+#define atom_read_lock()	erts_rwmtx_rlock(&atom_table_lock)
+#define atom_read_unlock()	erts_rwmtx_runlock(&atom_table_lock)
+#define atom_write_lock()	erts_rwmtx_rwlock(&atom_table_lock)
+#define atom_write_unlock()	erts_rwmtx_rwunlock(&atom_table_lock)
 
 #if 0
 #define ERTS_ATOM_PUT_OPS_STAT
 #endif
 #ifdef ERTS_ATOM_PUT_OPS_STAT
-static erts_smp_atomic_t atom_put_ops;
+static erts_atomic_t atom_put_ops;
 #endif
 
 /* Functions for allocating space for the ext of atoms. We do not
@@ -76,7 +74,7 @@ void atom_info(fmtfn_t to, void *to_arg)
     index_info(to, to_arg, &erts_atom_table);
 #ifdef ERTS_ATOM_PUT_OPS_STAT
     erts_print(to, to_arg, "atom_put_ops: %ld\n",
-	       erts_smp_atomic_read_nob(&atom_put_ops));
+	       erts_atomic_read_nob(&atom_put_ops));
 #endif
 
     if (lock)
@@ -246,7 +244,7 @@ erts_atom_put_index(const byte *name, int len, ErtsAtomEncoding enc, int trunc)
     int aix;
 
 #ifdef ERTS_ATOM_PUT_OPS_STAT
-    erts_smp_atomic_inc_nob(&atom_put_ops);
+    erts_atomic_inc_nob(&atom_put_ops);
 #endif
 
     if (tlen < 0) {
@@ -359,32 +357,24 @@ am_atom_put(const char* name, int len)
 int atom_table_size(void)
 {
     int ret;
-#ifdef ERTS_SMP
     int lock = !ERTS_IS_CRASH_DUMPING;
     if (lock)
 	atom_read_lock();
-#endif
     ret = erts_atom_table.entries;
-#ifdef ERTS_SMP
     if (lock)
 	atom_read_unlock();
-#endif
     return ret;
 }
 
 int atom_table_sz(void)
 {
     int ret;
-#ifdef ERTS_SMP
     int lock = !ERTS_IS_CRASH_DUMPING;
     if (lock)
 	atom_read_lock();
-#endif
     ret = index_table_sz(&erts_atom_table);
-#ifdef ERTS_SMP
     if (lock)
 	atom_read_unlock();
-#endif
     return ret;
 }
 
@@ -412,19 +402,15 @@ erts_atom_get(const char *name, int len, Eterm* ap, ErtsAtomEncoding enc)
 void
 erts_atom_get_text_space_sizes(Uint *reserved, Uint *used)
 {
-#ifdef ERTS_SMP
     int lock = !ERTS_IS_CRASH_DUMPING;
     if (lock)
 	atom_read_lock();
-#endif
     if (reserved)
 	*reserved = reserved_atom_space;
     if (used)
 	*used = atom_space;
-#ifdef ERTS_SMP
     if (lock)
 	atom_read_unlock();
-#endif
 }
 
 void
@@ -433,16 +419,16 @@ init_atom_table(void)
     HashFunctions f;
     int i;
     Atom a;
-    erts_smp_rwmtx_opt_t rwmtx_opt = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
+    erts_rwmtx_opt_t rwmtx_opt = ERTS_RWMTX_OPT_DEFAULT_INITER;
 
-    rwmtx_opt.type = ERTS_SMP_RWMTX_TYPE_FREQUENT_READ;
-    rwmtx_opt.lived = ERTS_SMP_RWMTX_LONG_LIVED;
+    rwmtx_opt.type = ERTS_RWMTX_TYPE_FREQUENT_READ;
+    rwmtx_opt.lived = ERTS_RWMTX_LONG_LIVED;
 
 #ifdef ERTS_ATOM_PUT_OPS_STAT
-    erts_smp_atomic_init_nob(&atom_put_ops, 0);
+    erts_atomic_init_nob(&atom_put_ops, 0);
 #endif
 
-    erts_smp_rwmtx_init_opt(&atom_table_lock, &rwmtx_opt, "atom_tab", NIL,
+    erts_rwmtx_init_opt(&atom_table_lock, &rwmtx_opt, "atom_tab", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
 
     f.hash = (H_FUN) atom_hash;
@@ -505,4 +491,4 @@ Uint
 erts_get_atom_limit(void)
 {
     return erts_atom_table.limit;
-}
\ No newline at end of file
+}
diff --git a/erts/emulator/beam/atom.names b/erts/emulator/beam/atom.names
index a44d23b181..cb4fab51f1 100644
--- a/erts/emulator/beam/atom.names
+++ b/erts/emulator/beam/atom.names
@@ -108,6 +108,7 @@ atom asynchronous
 atom atom
 atom atom_used
 atom attributes
+atom auto_connect
 atom await_microstate_accounting_modifications
 atom await_port_send_result
 atom await_proc_exit
@@ -198,9 +199,7 @@ atom debug_flags
 atom decimals
 atom default
 atom delay_trap
-atom dexit
 atom depth
-atom dgroup_leader
 atom dictionary
 atom dirty_bif_exception
 atom dirty_bif_result
@@ -217,9 +216,10 @@ atom discard
 atom display_items
 atom dist
 atom dist_cmd
+atom dist_ctrl_put_data
+atom dist_data
 atom Div='/'
 atom div
-atom dlink
 atom dmonitor_node
 atom dmonitor_p
 atom DollarDollar='$$'
@@ -228,9 +228,7 @@ atom dollar_endonly
 atom dotall
 atom driver
 atom driver_options
-atom dsend
 atom dsend_continue_trap
-atom dunlink
 atom duplicate_bag
 atom duplicated
 atom dupnames
@@ -350,6 +348,7 @@ atom instruction_counts
 atom invalid
 atom is_constant
 atom is_seq_trace
+atom iterator
 atom io
 atom keypos
 atom kill
@@ -642,6 +641,7 @@ atom suspending
 atom sys_misc
 atom system
 atom system_error
+atom system_flag_scheduler_wall_time
 atom system_limit
 atom system_version
 atom system_architecture
diff --git a/erts/emulator/beam/beam_bif_load.c b/erts/emulator/beam/beam_bif_load.c
index 023ee3ef4b..87367b44ab 100644
--- a/erts/emulator/beam/beam_bif_load.c
+++ b/erts/emulator/beam/beam_bif_load.c
@@ -50,7 +50,7 @@
 
 static struct {
     Eterm module;
-    erts_smp_mtx_t mtx;
+    erts_mtx_t mtx;
     Export *pending_purge_lambda;
     Eterm *sprocs;
     Eterm def_sprocs[10];
@@ -65,12 +65,10 @@ static struct {
 
 Process *erts_code_purger = NULL;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 Process *erts_dirty_process_code_checker;
-#endif
-erts_smp_atomic_t erts_copy_literal_area__;
+erts_atomic_t erts_copy_literal_area__;
 #define ERTS_SET_COPY_LITERAL_AREA(LA)			\
-    erts_smp_atomic_set_nob(&erts_copy_literal_area__,	\
+    erts_atomic_set_nob(&erts_copy_literal_area__,	\
 			    (erts_aint_t) (LA))
 Process *erts_literal_area_collector = NULL;
 
@@ -81,7 +79,7 @@ struct ErtsLiteralAreaRef_ {
 };
 
 struct {
-    erts_smp_mtx_t mtx;
+    erts_mtx_t mtx;
     ErtsLiteralAreaRef *first;
     ErtsLiteralAreaRef *last;
 } release_literal_areas;
@@ -97,7 +95,7 @@ init_purge_state(void)
 {
     purge_state.module = THE_NON_VALUE;
 
-    erts_smp_mtx_init(&purge_state.mtx, "purge_state", NIL,
+    erts_mtx_init(&purge_state.mtx, "purge_state", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
 
     purge_state.pending_purge_lambda =
@@ -119,12 +117,12 @@ init_purge_state(void)
 void
 erts_beam_bif_load_init(void)
 {
-    erts_smp_mtx_init(&release_literal_areas.mtx, "release_literal_areas", NIL,
+    erts_mtx_init(&release_literal_areas.mtx, "release_literal_areas", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
 
     release_literal_areas.first = NULL;
     release_literal_areas.last = NULL;
-    erts_smp_atomic_init_nob(&erts_copy_literal_area__,
+    erts_atomic_init_nob(&erts_copy_literal_area__,
 			     (erts_aint_t) NULL);
 
     init_purge_state();
@@ -172,8 +170,8 @@ BIF_RETTYPE code_make_stub_module_3(BIF_ALIST_3)
 			BIF_P, BIF_ARG_1, BIF_ARG_2, BIF_ARG_3);
     }
 
-    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-    erts_smp_thr_progress_block();
+    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    erts_thr_progress_block();
 
     modp = erts_get_module(mod, erts_active_code_ix());
 
@@ -197,8 +195,8 @@ BIF_RETTYPE code_make_stub_module_3(BIF_ALIST_3)
     else {
 	erts_abort_staging_code_ix();
     }
-    erts_smp_thr_progress_unblock();
-    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    erts_thr_progress_unblock();
+    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
     erts_release_code_write_permission();
     return res;
 #endif
@@ -265,7 +263,6 @@ struct m {
 };
 
 static Eterm staging_epilogue(Process* c_p, int, Eterm res, int, struct m*, int, int);
-#ifdef ERTS_SMP
 static void smp_code_ix_commiter(void*);
 
 static struct /* Protected by code_write_permission */
@@ -273,7 +270,6 @@ static struct /* Protected by code_write_permission */
     Process* stager;
     ErtsThrPrgrLaterOp lop;
 } committer_state;
-#endif
 
 static Eterm
 exception_list(Process* p, Eterm tag, struct m* mp, Sint exceptions)
@@ -401,8 +397,8 @@ finish_loading_1(BIF_ALIST_1)
 	    erts_is_default_trace_enabled() ||
 	    IF_HIPE(hipe_need_blocking(p[i].modp))) {
 	    /* tracing or hipe need thread blocking */
-	    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-	    erts_smp_thr_progress_block();
+	    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	    erts_thr_progress_block();
 	    is_blocking = 1;
 	    break;
 	}
@@ -465,9 +461,7 @@ static Eterm
 staging_epilogue(Process* c_p, int commit, Eterm res, int is_blocking,
 		 struct m* mods, int nmods, int free_mods)
 {    
-#ifdef ERTS_SMP
     if (is_blocking || !commit)
-#endif
     {
 	if (commit) {
 	    int i;
@@ -491,13 +485,12 @@ staging_epilogue(Process* c_p, int commit, Eterm res, int is_blocking,
 	    erts_free(ERTS_ALC_T_LOADER_TMP, mods);
 	}
 	if (is_blocking) {
-	    erts_smp_thr_progress_unblock();
-	    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+	    erts_thr_progress_unblock();
+	    erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
 	}
 	erts_release_code_write_permission();
 	return res;
     }
-#ifdef ERTS_SMP
     else {
 	ASSERT(is_value(res));
 
@@ -522,11 +515,9 @@ staging_epilogue(Process* c_p, int commit, Eterm res, int is_blocking,
 	 */
 	ERTS_BIF_YIELD_RETURN(c_p, res);
     }
-#endif
 }
 
 
-#ifdef ERTS_SMP
 static void smp_code_ix_commiter(void* null)
 {
     Process* p = committer_state.stager;
@@ -536,14 +527,13 @@ static void smp_code_ix_commiter(void* null)
     committer_state.stager = NULL;
 #endif
     erts_release_code_write_permission();
-    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
     if (!ERTS_PROC_IS_EXITING(p)) {
 	erts_resume(p, ERTS_PROC_LOCK_STATUS);
     }
-    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
     erts_proc_dec_refc(p);
 }
-#endif /* ERTS_SMP */
 
 
 
@@ -613,9 +603,6 @@ badarg:
 
 BIF_RETTYPE erts_internal_check_dirty_process_code_2(BIF_ALIST_2)
 {
-#if !defined(ERTS_DIRTY_SCHEDULERS)
-    BIF_ERROR(BIF_P, EXC_NOTSUP);
-#else
     Process *rp;
     int reds = 0;
     Eterm res;
@@ -640,12 +627,11 @@ BIF_RETTYPE erts_internal_check_dirty_process_code_2(BIF_ALIST_2)
     res = erts_check_process_code(rp, BIF_ARG_2, &reds, BIF_P->fcalls);
 
     if (BIF_P != rp)
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_MAIN);
 
     ASSERT(is_value(res));
 
     BIF_RET2(res, reds);
-#endif
 }
 
 BIF_RETTYPE delete_module_1(BIF_ALIST_1)
@@ -683,8 +669,8 @@ BIF_RETTYPE delete_module_1(BIF_ALIST_1)
 		modp->curr.num_traced_exports > 0 ||
 		IF_HIPE(hipe_need_blocking(modp))) {
 		/* tracing or hipe need to go single threaded */
-		erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-		erts_smp_thr_progress_block();
+		erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+		erts_thr_progress_block();
 		is_blocking = 1;
 		if (modp->curr.num_breakpoints) {
 		    erts_clear_module_break(modp);
@@ -782,36 +768,45 @@ BIF_RETTYPE finish_after_on_load_2(BIF_ALIST_2)
     ErtsCodeIndex code_ix;
     Module* modp;
 
+    if (BIF_ARG_2 != am_false && BIF_ARG_2 != am_true) {
+	BIF_ERROR(BIF_P, BADARG);
+    }
+
     if (!erts_try_seize_code_write_permission(BIF_P)) {
 	ERTS_BIF_YIELD2(bif_export[BIF_finish_after_on_load_2],
 			BIF_P, BIF_ARG_1, BIF_ARG_2);
     }
 
-    /* ToDo: Use code_ix staging instead of thread blocking */
-
-    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-    erts_smp_thr_progress_block();
-
     code_ix = erts_active_code_ix();
     modp = erts_get_module(BIF_ARG_1, code_ix);
 
-    if (!modp || !modp->on_load || !modp->on_load->code_hdr) {
-    error:
-	erts_smp_thr_progress_unblock();
-        erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    if (!modp || !modp->on_load || !modp->on_load->code_hdr
+	|| !modp->on_load->code_hdr->on_load_function_ptr) {
+
 	erts_release_code_write_permission();
 	BIF_ERROR(BIF_P, BADARG);
     }
-    if (modp->on_load->code_hdr->on_load_function_ptr == NULL) {
-	goto error;
-    }
-    if (BIF_ARG_2 != am_false && BIF_ARG_2 != am_true) {
-	goto error;
-    }
 
     if (BIF_ARG_2 == am_true) {
+	struct m mods[1];
+	int is_blocking = 0;
 	int i, num_exps;
 
+	erts_start_staging_code_ix(0);
+	code_ix = erts_staging_code_ix();
+	modp = erts_get_module(BIF_ARG_1, code_ix);
+
+	ASSERT(modp && modp->on_load && modp->on_load->code_hdr
+	       && modp->on_load->code_hdr->on_load_function_ptr);
+
+        if (erts_is_default_trace_enabled()
+	    || IF_HIPE(hipe_need_blocking(modp))) {
+
+            erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+            erts_thr_progress_block();
+            is_blocking = 1;
+	}
+
 	/*
 	 * Make the code with the on_load function current.
 	 */
@@ -837,19 +832,21 @@ BIF_RETTYPE finish_after_on_load_2(BIF_ALIST_2)
 		ep->beam[1] = 0;
 	    } else {
 		if (ep->addressv[code_ix] == ep->beam &&
-		    ep->beam[0] == (BeamInstr) em_apply_bif) {
+		    BeamIsOpCode(ep->beam[0], op_apply_bif)) {
 		    continue;
 		}
-		ep->addressv[code_ix] = ep->beam;
-		ep->beam[0] = (BeamInstr) em_call_error_handler;
+                ep->addressv[code_ix] = ep->beam;
+                ep->beam[0] = BeamOpCodeAddr(op_call_error_handler);
 	    }
 	}
 	modp->curr.code_hdr->on_load_function_ptr = NULL;
-	set_default_trace_pattern(BIF_ARG_1);
-      #ifdef HIPE
-        hipe_redirect_to_module(modp);
-      #endif
-    } else if (BIF_ARG_2 == am_false) {
+
+	mods[0].modp = modp;
+	mods[0].module = BIF_ARG_1;
+        mods[0].exception = THE_NON_VALUE;
+	return staging_epilogue(BIF_P, 1, am_true, is_blocking, mods, 1, 0);
+    }
+    else if (BIF_ARG_2 == am_false) {
 	int i, num_exps;
 
 	/*
@@ -863,14 +860,12 @@ BIF_RETTYPE finish_after_on_load_2(BIF_ALIST_2)
 	    if (ep == NULL || ep->info.mfa.module != BIF_ARG_1) {
 		continue;
 	    }
-	    if (ep->beam[0] == (BeamInstr) em_apply_bif) {
+	    if (BeamIsOpCode(ep->beam[0], op_apply_bif)) {
 		continue;
 	    }
 	    ep->beam[1] = 0;
 	}
     }
-    erts_smp_thr_progress_unblock();
-    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
     erts_release_code_write_permission();
     BIF_RET(am_true);
 }
@@ -931,9 +926,9 @@ erts_proc_copy_literal_area(Process *c_p, int *redsp, int fcalls, int gc_allowed
      * any other heap than the message it self.
      */
 
-    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ);
-    ERTS_SMP_MSGQ_MV_INQ2PRIVQ(c_p);
-    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ);
+    erts_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ);
+    ERTS_MSGQ_MV_INQ2PRIVQ(c_p);
+    erts_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ);
 
     for (msgp = c_p->msg.first; msgp; msgp = msgp->next) {
 	ErlHeapFragment *hf;
@@ -1063,10 +1058,8 @@ erts_proc_copy_literal_area(Process *c_p, int *redsp, int fcalls, int gc_allowed
 
 return_ok:
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (ERTS_SCHEDULER_IS_DIRTY(erts_proc_sched_data(c_p)))
 	c_p->flags &= ~F_DIRTY_CLA;
-#endif
 
     return am_ok;
 
@@ -1081,10 +1074,8 @@ literal_gc:
     *redsp += erts_garbage_collect_literals(c_p, (Eterm *) literals, lit_bsize,
 					    oh, fcalls);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (c_p->flags & F_DIRTY_CLA)
 	return THE_NON_VALUE;
-#endif
 
     return am_ok;
 }
@@ -1314,7 +1305,6 @@ hfrag_literal_copy(Eterm **hpp, ErlOffHeap *ohp,
     }
 }
 
-#ifdef ERTS_SMP
 
 ErtsThrPrgrLaterOp later_literal_area_switch;
 
@@ -1336,13 +1326,12 @@ static void
 complete_literal_area_switch(void *literal_area)
 {
     Process *p = erts_literal_area_collector;
-    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
     erts_resume(p, ERTS_PROC_LOCK_STATUS);
-    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
     if (literal_area)
 	erts_release_literal_area((ErtsLiteralArea *) literal_area);
 }
-#endif
 
 BIF_RETTYPE erts_internal_release_literal_area_switch_0(BIF_ALIST_0)
 {
@@ -1352,7 +1341,7 @@ BIF_RETTYPE erts_internal_release_literal_area_switch_0(BIF_ALIST_0)
     if (BIF_P != erts_literal_area_collector)
 	BIF_ERROR(BIF_P, EXC_NOTSUP);
 
-    erts_smp_mtx_lock(&release_literal_areas.mtx);
+    erts_mtx_lock(&release_literal_areas.mtx);
 
     la_ref = release_literal_areas.first;
     if (la_ref) {
@@ -1361,14 +1350,13 @@ BIF_RETTYPE erts_internal_release_literal_area_switch_0(BIF_ALIST_0)
 	    release_literal_areas.last = NULL;
     }
 
-    erts_smp_mtx_unlock(&release_literal_areas.mtx);
+    erts_mtx_unlock(&release_literal_areas.mtx);
 
     unused_la = ERTS_COPY_LITERAL_AREA();
 
     if (!la_ref) {
 	ERTS_SET_COPY_LITERAL_AREA(NULL);
 	if (unused_la) {
-#ifdef ERTS_SMP
 	    ErtsLaterReleasLiteralArea *lrlap;
 	    lrlap = erts_alloc(ERTS_ALC_T_RELEASE_LAREA,
 			       sizeof(ErtsLaterReleasLiteralArea));
@@ -1382,9 +1370,6 @@ BIF_RETTYPE erts_internal_release_literal_area_switch_0(BIF_ALIST_0)
 		 + ((unused_la->end
 		     - &unused_la->start[0])
 		    - 1)*(sizeof(Eterm))));
-#else
-	    erts_release_literal_area(unused_la);
-#endif
 	}
 	BIF_RET(am_false);
     }
@@ -1393,16 +1378,11 @@ BIF_RETTYPE erts_internal_release_literal_area_switch_0(BIF_ALIST_0)
 
     erts_free(ERTS_ALC_T_LITERAL_REF, la_ref);
 
-#ifdef ERTS_SMP
     erts_schedule_thr_prgr_later_op(complete_literal_area_switch,
 				    unused_la,
 				    &later_literal_area_switch);
     erts_suspend(BIF_P, ERTS_PROC_LOCK_MAIN, NULL);
     ERTS_BIF_YIELD_RETURN(BIF_P, am_true);
-#else
-    erts_release_literal_area(unused_la);
-    BIF_RET(am_true);
-#endif
 
 }
 
@@ -1428,7 +1408,7 @@ erts_purge_state_add_fun(ErlFunEntry *fe)
 Export *
 erts_suspend_process_on_pending_purge_lambda(Process *c_p, ErlFunEntry* fe)
 {
-    erts_smp_mtx_lock(&purge_state.mtx);
+    erts_mtx_lock(&purge_state.mtx);
     if (purge_state.module == fe->module) {
 	/*
 	 * The process c_p is about to call a fun in the code
@@ -1454,7 +1434,7 @@ erts_suspend_process_on_pending_purge_lambda(Process *c_p, ErlFunEntry* fe)
 	erts_suspend(c_p, ERTS_PROC_LOCK_MAIN, NULL);
 	ERTS_VBUMP_ALL_REDS(c_p);
     }
-    erts_smp_mtx_unlock(&purge_state.mtx);
+    erts_mtx_unlock(&purge_state.mtx);
     return purge_state.pending_purge_lambda;
 }
 
@@ -1464,9 +1444,9 @@ finalize_purge_operation(Process *c_p, int succeded)
     Uint ix;
 
     if (c_p)
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
 
-    erts_smp_mtx_lock(&purge_state.mtx);
+    erts_mtx_lock(&purge_state.mtx);
 
     ASSERT(purge_state.module != THE_NON_VALUE);
 
@@ -1482,14 +1462,14 @@ finalize_purge_operation(Process *c_p, int succeded)
 				    ERTS_PROC_LOCK_STATUS);
 	if (rp) {
 	    erts_resume(rp, ERTS_PROC_LOCK_STATUS);
-	    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
 	}
     }
 
-    erts_smp_mtx_unlock(&purge_state.mtx);
+    erts_mtx_unlock(&purge_state.mtx);
 
     if (c_p)
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+	erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
 
     if (purge_state.sprocs != &purge_state.def_sprocs[0]) {
 	erts_free(ERTS_ALC_T_PURGE_DATA, purge_state.sprocs);
@@ -1508,7 +1488,6 @@ finalize_purge_operation(Process *c_p, int succeded)
     purge_state.fe_ix = 0;
 }
 
-#ifdef ERTS_SMP
 
 static ErtsThrPrgrLaterOp purger_lop_data;
 
@@ -1516,9 +1495,9 @@ static void
 resume_purger(void *unused)
 {
     Process *p = erts_code_purger;
-    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
     erts_resume(p, ERTS_PROC_LOCK_STATUS);
-    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
 }
 
 static void
@@ -1531,7 +1510,6 @@ finalize_purge_abort(void *unused)
     resume_purger(NULL);
 }
 
-#endif /* ERTS_SMP */
 
 BIF_RETTYPE erts_internal_purge_module_2(BIF_ALIST_2)
 {
@@ -1590,9 +1568,9 @@ BIF_RETTYPE erts_internal_purge_module_2(BIF_ALIST_2)
 	    else {
 		BeamInstr* code;
 		BeamInstr* end;
-		erts_smp_mtx_lock(&purge_state.mtx);
+		erts_mtx_lock(&purge_state.mtx);
 		purge_state.module = BIF_ARG_1;
-		erts_smp_mtx_unlock(&purge_state.mtx);
+		erts_mtx_unlock(&purge_state.mtx);
 		res = am_true;
 		code = (BeamInstr*) modp->old.code_hdr;
 		end = (BeamInstr *)((char *)code + modp->old.code_length);
@@ -1606,9 +1584,6 @@ BIF_RETTYPE erts_internal_purge_module_2(BIF_ALIST_2)
 	    }
 	}
 	
-#ifndef ERTS_SMP
-	BIF_RET(res);
-#else
 	if (res != am_true)
 	    BIF_RET(res);
 	else {
@@ -1627,7 +1602,6 @@ BIF_RETTYPE erts_internal_purge_module_2(BIF_ALIST_2)
 	    erts_suspend(BIF_P, ERTS_PROC_LOCK_MAIN, NULL);
 	    ERTS_BIF_YIELD_RETURN(BIF_P, am_true);
 	}
-#endif
     }
 
     case am_abort: {
@@ -1641,11 +1615,6 @@ BIF_RETTYPE erts_internal_purge_module_2(BIF_ALIST_2)
 
 	erts_fun_purge_abort_prepare(purge_state.funs, purge_state.fe_ix);
 
-#ifndef ERTS_SMP
-	erts_fun_purge_abort_finalize(purge_state.funs, purge_state.fe_ix);
-	finalize_purge_operation(BIF_P, 0);
-	BIF_RET(am_false);
-#else
 	/*
 	 * We need to restore the code addresses of the funs in
 	 * two stages in order to ensure that we do not get any
@@ -1661,7 +1630,6 @@ BIF_RETTYPE erts_internal_purge_module_2(BIF_ALIST_2)
 					&purger_lop_data);
 	erts_suspend(BIF_P, ERTS_PROC_LOCK_MAIN, NULL);
 	ERTS_BIF_YIELD_RETURN(BIF_P, am_false);
-#endif
     }
 
     case am_complete: {
@@ -1713,8 +1681,8 @@ BIF_RETTYPE erts_internal_purge_module_2(BIF_ALIST_2)
 		    || IF_HIPE(hipe_purge_need_blocking(modp))) {
 		    /* ToDo: Do unload nif without blocking */
 		    erts_rwunlock_old_code(code_ix);
-		    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-		    erts_smp_thr_progress_block();
+		    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+		    erts_thr_progress_block();
 		    is_blocking = 1;
 		    erts_rwlock_old_code(code_ix);
 		    if (modp->old.nif) {
@@ -1752,8 +1720,8 @@ BIF_RETTYPE erts_internal_purge_module_2(BIF_ALIST_2)
 	    erts_rwunlock_old_code(code_ix);
 	}
 	if (is_blocking) {
-	    erts_smp_thr_progress_unblock();
-	    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	    erts_thr_progress_unblock();
+	    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 	}
 
 	erts_release_code_write_permission();
@@ -1766,7 +1734,7 @@ BIF_RETTYPE erts_internal_purge_module_2(BIF_ALIST_2)
 			     sizeof(ErtsLiteralAreaRef));
 	    ref->literal_area = literals;
 	    ref->next = NULL;
-	    erts_smp_mtx_lock(&release_literal_areas.mtx);
+	    erts_mtx_lock(&release_literal_areas.mtx);
 	    if (release_literal_areas.last) {
 		release_literal_areas.last->next = ref;
 		release_literal_areas.last = ref;
@@ -1775,7 +1743,7 @@ BIF_RETTYPE erts_internal_purge_module_2(BIF_ALIST_2)
 		release_literal_areas.first = ref;
 		release_literal_areas.last = ref;
 	    }
-	    erts_smp_mtx_unlock(&release_literal_areas.mtx);
+	    erts_mtx_unlock(&release_literal_areas.mtx);
 	    erts_queue_message(erts_literal_area_collector,
 			       0,
 			       erts_alloc_message(0, NULL),
@@ -1807,22 +1775,23 @@ delete_code(Module* modp)
 	Export *ep = export_list(i, code_ix);
         if (ep != NULL && (ep->info.mfa.module == module)) {
 	    if (ep->addressv[code_ix] == ep->beam) {
-		if (ep->beam[0] == (BeamInstr) em_apply_bif) {
+		if (BeamIsOpCode(ep->beam[0], op_apply_bif)) {
 		    continue;
 		}
-		else if (ep->beam[0] ==
-			 (BeamInstr) BeamOp(op_i_generic_breakpoint)) {
-		    ERTS_SMP_LC_ASSERT(erts_smp_thr_progress_is_blocking());
+		else if (BeamIsOpCode(ep->beam[0], op_i_generic_breakpoint)) {
+		    ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
 		    ASSERT(modp->curr.num_traced_exports > 0);
 		    DBG_TRACE_MFA_P(&ep->info.mfa,
 				  "export trace cleared, code_ix=%d", code_ix);
 		    erts_clear_export_break(modp, &ep->info);
 		}
-		else ASSERT(ep->beam[0] == (BeamInstr) em_call_error_handler
-			    || !erts_initialized);
-	    }
+		else {
+                    ASSERT(BeamIsOpCode(ep->beam[0], op_call_error_handler) ||
+                           !erts_initialized);
+                }
+            }
 	    ep->addressv[code_ix] = ep->beam;
-	    ep->beam[0] = (BeamInstr) em_call_error_handler;
+	    ep->beam[0] = BeamOpCodeAddr(op_call_error_handler);
 	    ep->beam[1] = 0;
 	    DBG_TRACE_MFA_P(&ep->info.mfa,
 			    "export invalidation, code_ix=%d", code_ix);
diff --git a/erts/emulator/beam/beam_bp.c b/erts/emulator/beam/beam_bp.c
index 069e7391fd..0832b3f374 100644
--- a/erts/emulator/beam/beam_bp.c
+++ b/erts/emulator/beam/beam_bp.c
@@ -46,15 +46,15 @@
 #define ReAlloc(P, SIZ)		erts_realloc(ERTS_ALC_T_BPD, (P), (SZ))
 #define Free(P)			erts_free(ERTS_ALC_T_BPD, (P))
 
-#if defined(ERTS_ENABLE_LOCK_CHECK) && defined(ERTS_SMP)
-#  define ERTS_SMP_REQ_PROC_MAIN_LOCK(P) \
+#if defined(ERTS_ENABLE_LOCK_CHECK)
+#  define ERTS_REQ_PROC_MAIN_LOCK(P) \
       if ((P)) erts_proc_lc_require_lock((P), ERTS_PROC_LOCK_MAIN,\
 					 __FILE__, __LINE__)
-#  define ERTS_SMP_UNREQ_PROC_MAIN_LOCK(P) \
+#  define ERTS_UNREQ_PROC_MAIN_LOCK(P) \
       if ((P)) erts_proc_lc_unrequire_lock((P), ERTS_PROC_LOCK_MAIN)
 #else
-#  define ERTS_SMP_REQ_PROC_MAIN_LOCK(P)
-#  define ERTS_SMP_UNREQ_PROC_MAIN_LOCK(P)
+#  define ERTS_REQ_PROC_MAIN_LOCK(P)
+#  define ERTS_UNREQ_PROC_MAIN_LOCK(P)
 #endif
 
 #define ERTS_BPF_LOCAL_TRACE       0x01
@@ -73,11 +73,9 @@ extern BeamInstr beam_return_trace[1];      /* OpCode(i_return_trace) */
 extern BeamInstr beam_exception_trace[1];   /* OpCode(i_exception_trace) */
 extern BeamInstr beam_return_time_trace[1]; /* OpCode(i_return_time_trace) */
 
-erts_smp_atomic32_t erts_active_bp_index;
-erts_smp_atomic32_t erts_staging_bp_index;
-#ifdef ERTS_DIRTY_SCHEDULERS
-erts_smp_mtx_t erts_dirty_bp_ix_mtx;
-#endif
+erts_atomic32_t erts_active_bp_index;
+erts_atomic32_t erts_staging_bp_index;
+erts_mtx_t erts_dirty_bp_ix_mtx;
 
 /*
  * Inlined helpers
@@ -94,22 +92,18 @@ acquire_bp_sched_ix(Process *c_p)
 {
     ErtsSchedulerData *esdp = erts_proc_sched_data(c_p);
     ASSERT(esdp);
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (ERTS_SCHEDULER_IS_DIRTY(esdp)) {
-	erts_smp_mtx_lock(&erts_dirty_bp_ix_mtx);
+	erts_mtx_lock(&erts_dirty_bp_ix_mtx);
         return (Uint32) erts_no_schedulers;
     }
-#endif
     return (Uint32) esdp->no - 1;
 }
 
 static ERTS_INLINE void
 release_bp_sched_ix(Uint32 ix)
 {
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (ix == (Uint32) erts_no_schedulers)
-        erts_smp_mtx_unlock(&erts_dirty_bp_ix_mtx);
-#endif
+        erts_mtx_unlock(&erts_dirty_bp_ix_mtx);
 }
 
 
@@ -162,12 +156,10 @@ static void bp_hash_delete(bp_time_hash_t *hash);
 
 void 
 erts_bp_init(void) {
-    erts_smp_atomic32_init_nob(&erts_active_bp_index, 0);
-    erts_smp_atomic32_init_nob(&erts_staging_bp_index, 1);
-#ifdef ERTS_DIRTY_SCHEDULERS
-    erts_smp_mtx_init(&erts_dirty_bp_ix_mtx, "dirty_break_point_index", NIL,
+    erts_atomic32_init_nob(&erts_active_bp_index, 0);
+    erts_atomic32_init_nob(&erts_staging_bp_index, 1);
+    erts_mtx_init(&erts_dirty_bp_ix_mtx, "dirty_break_point_index", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_DEBUG);
-#endif
 }
 
 
@@ -211,7 +203,7 @@ erts_bp_match_functions(BpFunctions* f, ErtsCodeMFA *mfa, int specified)
 	for (fi = 0; fi < num_functions; fi++) {
 
 	    ci = code_hdr->functions[fi];
-	    ASSERT(ci->op == (BeamInstr) BeamOp(op_i_func_info_IaaI));
+	    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
 	    if (erts_is_function_native(ci)) {
 		continue;
 	    }
@@ -273,11 +265,11 @@ erts_bp_match_export(BpFunctions* f, ErtsCodeMFA *mfa, int specified)
 
 	pc = ep->beam;
 	if (ep->addressv[code_ix] == pc) {
-	    if ((*pc == (BeamInstr) em_apply_bif ||
-		 *pc == (BeamInstr) em_call_error_handler)) {
-		continue;
+	    if (BeamIsOpCode(*pc, op_apply_bif) ||
+                BeamIsOpCode(*pc, op_call_error_handler)) {
+                continue;
 	    }
-	    ASSERT(*pc == (BeamInstr) BeamOp(op_i_generic_breakpoint));
+	    ASSERT(BeamIsOpCode(*pc, op_i_generic_breakpoint));
 	} else if (erts_is_function_native(erts_code_to_codeinfo(ep->addressv[code_ix]))) {
 	    continue;
 	}
@@ -306,7 +298,7 @@ erts_consolidate_bp_data(BpFunctions* f, int local)
     Uint i;
     Uint n = f->matched;
 
-    ERTS_SMP_LC_ASSERT(erts_has_code_write_permission());
+    ERTS_LC_ASSERT(erts_has_code_write_permission());
 
     for (i = 0; i < n; i++) {
 	consolidate_bp_data(fs[i].mod, fs[i].ci, local);
@@ -318,7 +310,7 @@ erts_consolidate_bif_bp_data(void)
 {
     int i;
 
-    ERTS_SMP_LC_ASSERT(erts_has_code_write_permission());
+    ERTS_LC_ASSERT(erts_has_code_write_permission());
     for (i = 0; i < BIF_SIZE; i++) {
 	Export *ep = bif_export[i];
 	consolidate_bp_data(0, &ep->info, 0);
@@ -374,8 +366,8 @@ consolidate_bp_data(Module* modp, ErtsCodeInfo *ci, int local)
 	    }
 	    ASSERT(modp->curr.num_breakpoints >= 0);
 	    ASSERT(modp->curr.num_traced_exports >= 0);
-	    ASSERT(*erts_codeinfo_to_code(ci) !=
-                   (BeamInstr) BeamOp(op_i_generic_breakpoint));
+	    ASSERT(! BeamIsOpCode(*erts_codeinfo_to_code(ci),
+                                  op_i_generic_breakpoint));
 	}
 	ci->u.gen_bp = NULL;
 	Free(g);
@@ -393,17 +385,17 @@ consolidate_bp_data(Module* modp, ErtsCodeInfo *ci, int local)
     }
     if (flags & ERTS_BPF_META_TRACE) {
 	dst->meta_tracer = src->meta_tracer;
-	erts_smp_refc_inc(&dst->meta_tracer->refc, 1);
+	erts_refc_inc(&dst->meta_tracer->refc, 1);
 	dst->meta_ms = src->meta_ms;
 	MatchSetRef(dst->meta_ms);
     }
     if (flags & ERTS_BPF_COUNT) {
 	dst->count = src->count;
-	erts_smp_refc_inc(&dst->count->refc, 1);
+	erts_refc_inc(&dst->count->refc, 1);
     }
     if (flags & ERTS_BPF_TIME_TRACE) {
 	dst->time = src->time;
-	erts_smp_refc_inc(&dst->time->refc, 1);
+	erts_refc_inc(&dst->time->refc, 1);
 	ASSERT(dst->time->hash);
     }
 }
@@ -414,8 +406,8 @@ erts_commit_staged_bp(void)
     ErtsBpIndex staging = erts_staging_bp_ix();
     ErtsBpIndex active = erts_active_bp_ix();
 
-    erts_smp_atomic32_set_nob(&erts_active_bp_index, staging);
-    erts_smp_atomic32_set_nob(&erts_staging_bp_index, active);
+    erts_atomic32_set_nob(&erts_active_bp_index, staging);
+    erts_atomic32_set_nob(&erts_staging_bp_index, active);
 }
 
 void
@@ -423,13 +415,15 @@ erts_install_breakpoints(BpFunctions* f)
 {
     Uint i;
     Uint n = f->matched;
-    BeamInstr br = (BeamInstr) BeamOp(op_i_generic_breakpoint);
+    BeamInstr br = BeamOpCodeAddr(op_i_generic_breakpoint);
 
     for (i = 0; i < n; i++) {
 	ErtsCodeInfo* ci = f->matching[i].ci;
-        BeamInstr *pc = erts_codeinfo_to_code(ci);
 	GenericBp* g = ci->u.gen_bp;
-	if (*pc != br && g) {
+        BeamInstr volatile *pc = erts_codeinfo_to_code(ci);
+        BeamInstr instr = *pc;
+
+	if (!BeamIsOpCode(instr, op_i_generic_breakpoint) && g) {
 	    Module* modp = f->matching[i].mod;
 
 	    /*
@@ -443,11 +437,16 @@ erts_install_breakpoints(BpFunctions* f)
 	    /*
 	     * The following write is not protected by any lock. We
 	     * assume that the hardware guarantees that a write of an
-	     * aligned word-size (or half-word) writes is atomic
-	     * (i.e. that other processes executing this code will not
-	     * see a half pointer).
+	     * aligned word-size writes is atomic (i.e. that other
+	     * processes executing this code will not see a half
+	     * pointer).
+             *
+             * The contents of *pc is marked 'volatile' to ensure that
+             * the compiler will do a single full-word write, and not
+             * try any fancy optimizations to write a half word.
 	     */
-	    *pc = br;
+            instr = BeamSetCodeAddr(instr, br);
+            *pc = instr;
 	    modp->curr.num_breakpoints++;
 	}
     }
@@ -468,7 +467,7 @@ static void
 uninstall_breakpoint(ErtsCodeInfo *ci)
 {
     BeamInstr *pc = erts_codeinfo_to_code(ci);
-    if (*pc == (BeamInstr) BeamOp(op_i_generic_breakpoint)) {
+    if (BeamIsOpCode(*pc, op_i_generic_breakpoint)) {
 	GenericBp* g = ci->u.gen_bp;
 	if (g->data[erts_active_bp_ix()].flags == 0) {
 	    /*
@@ -575,7 +574,7 @@ erts_clear_mtrace_bif(ErtsCodeInfo *ci)
 void
 erts_clear_debug_break(BpFunctions* f)
 {
-    ERTS_SMP_LC_ASSERT(erts_smp_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
     clear_break(f, ERTS_BPF_DEBUG);
 }
 
@@ -603,7 +602,7 @@ erts_clear_module_break(Module *modp) {
     Uint n;
     Uint i;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
     ASSERT(modp);
     code_hdr = modp->curr.code_hdr;
     if (!code_hdr) {
@@ -633,7 +632,7 @@ erts_clear_module_break(Module *modp) {
 void
 erts_clear_export_break(Module* modp, ErtsCodeInfo *ci)
 {
-    ERTS_SMP_LC_ASSERT(erts_smp_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
 
     clear_function_break(ci, ERTS_BPF_ALL);
     erts_commit_staged_bp();
@@ -656,12 +655,12 @@ static void fixup_cp_before_trace(Process *c_p, int *return_to_trace)
 {
     Eterm *cpp, *E = c_p->stop;
     BeamInstr w = *c_p->cp;
-    if (w == (BeamInstr) BeamOp(op_return_trace)) {
+    if (BeamIsOpCode(w, op_return_trace)) {
         cpp = &E[2];
-    } else if (w == (BeamInstr) BeamOp(op_i_return_to_trace)) {
+    } else if (BeamIsOpCode(w, op_i_return_to_trace)) {
         *return_to_trace = 1;
         cpp = &E[0];
-    } else if (w == (BeamInstr) BeamOp(op_i_return_time_trace)) {
+    } else if (BeamIsOpCode(w, op_i_return_time_trace)) {
         cpp = &E[0];
     } else {
         cpp = NULL;
@@ -669,12 +668,12 @@ static void fixup_cp_before_trace(Process *c_p, int *return_to_trace)
     if (cpp) {
         for (;;) {
             BeamInstr w = *cp_val(*cpp);
-            if (w == (BeamInstr) BeamOp(op_return_trace)) {
+            if (BeamIsOpCode(w, op_return_trace)) {
                 cpp += 3;
-            } else if (w == (BeamInstr) BeamOp(op_i_return_to_trace)) {
+            } else if (BeamIsOpCode(w, op_i_return_to_trace)) {
                 *return_to_trace = 1;
                 cpp += 1;
-            } else if (w == (BeamInstr) BeamOp(op_i_return_time_trace)) {
+            } else if (BeamIsOpCode(w, op_i_return_time_trace)) {
                 cpp += 2;
             } else {
                 break;
@@ -693,7 +692,7 @@ erts_generic_breakpoint(Process* c_p, ErtsCodeInfo *info, Eterm* reg)
     Uint bp_flags;
     ErtsBpIndex ix = erts_active_bp_ix();
 
-    ASSERT(info->op == (BeamInstr) BeamOp(op_i_func_info_IaaI));
+    ASSERT(BeamIsOpCode(info->op, op_i_func_info_IaaI));
 
     g = info->u.gen_bp;
     bp = &g->data[ix];
@@ -722,12 +721,12 @@ erts_generic_breakpoint(Process* c_p, ErtsCodeInfo *info, Eterm* reg)
     if (bp_flags & ERTS_BPF_META_TRACE) {
 	ErtsTracer old_tracer, new_tracer;
 
-	old_tracer = erts_smp_atomic_read_nob(&bp->meta_tracer->tracer);
+	old_tracer = erts_atomic_read_nob(&bp->meta_tracer->tracer);
 
 	new_tracer = do_call_trace(c_p, info, reg, 1, bp->meta_ms, old_tracer);
 
 	if (!ERTS_TRACER_COMPARE(new_tracer, old_tracer)) {
-            if (old_tracer == erts_smp_atomic_cmpxchg_acqb(
+            if (old_tracer == erts_atomic_cmpxchg_acqb(
                     &bp->meta_tracer->tracer,
                     (erts_aint_t)new_tracer,
                     (erts_aint_t)old_tracer)) {
@@ -739,16 +738,16 @@ erts_generic_breakpoint(Process* c_p, ErtsCodeInfo *info, Eterm* reg)
     }
 
     if (bp_flags & ERTS_BPF_COUNT_ACTIVE) {
-	erts_smp_atomic_inc_nob(&bp->count->acount);
+	erts_atomic_inc_nob(&bp->count->acount);
     }
 
     if (bp_flags & ERTS_BPF_TIME_TRACE_ACTIVE) {
 	Eterm w;
 	erts_trace_time_call(c_p, info, bp->time);
 	w = (BeamInstr) *c_p->cp;
-	if (! (w == (BeamInstr) BeamOp(op_i_return_time_trace) ||
-	       w == (BeamInstr) BeamOp(op_return_trace) ||
-	       w == (BeamInstr) BeamOp(op_i_return_to_trace)) ) {
+	if (! (BeamIsOpCode(w, op_i_return_time_trace) ||
+	       BeamIsOpCode(w, op_return_trace) ||
+               BeamIsOpCode(w, op_i_return_to_trace)) ) {
 	    Eterm* E = c_p->stop;
 	    ASSERT(c_p->htop <= E && E <= c_p->hend);
 	    if (E - 2 < c_p->htop) {
@@ -768,7 +767,7 @@ erts_generic_breakpoint(Process* c_p, ErtsCodeInfo *info, Eterm* reg)
     }
 
     if (bp_flags & ERTS_BPF_DEBUG) {
-	return (BeamInstr) BeamOp(op_i_debug_breakpoint);
+	return BeamOpCodeAddr(op_i_debug_breakpoint);
     } else {
 	return g->orig_instr;
     }
@@ -797,7 +796,7 @@ erts_bif_trace(int bif_index, Process* p, Eterm* args, BeamInstr* I)
     Uint bp_flags = 0;
     int return_to_trace = 0;
 
-    ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
+    ERTS_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
 
     g = ep->info.u.gen_bp;
     if (g) {
@@ -823,7 +822,7 @@ erts_bif_trace(int bif_index, Process* p, Eterm* args, BeamInstr* I)
     if (bp_flags & ERTS_BPF_META_TRACE) {
 	ErtsTracer old_tracer;
 
-        meta_tracer = erts_smp_atomic_read_nob(&bp->meta_tracer->tracer);
+        meta_tracer = erts_atomic_read_nob(&bp->meta_tracer->tracer);
         old_tracer = meta_tracer;
 	flags_meta = erts_call_trace(p, &ep->info, bp->meta_ms, args,
 				     0, &meta_tracer);
@@ -831,7 +830,7 @@ erts_bif_trace(int bif_index, Process* p, Eterm* args, BeamInstr* I)
 	if (!ERTS_TRACER_COMPARE(old_tracer, meta_tracer)) {
             ErtsTracer new_tracer = erts_tracer_nil;
             erts_tracer_update(&new_tracer, meta_tracer);
-	    if (old_tracer == erts_smp_atomic_cmpxchg_acqb(
+	    if (old_tracer == erts_atomic_cmpxchg_acqb(
                     &bp->meta_tracer->tracer,
                     (erts_aint_t)new_tracer,
                     (erts_aint_t)old_tracer)) {
@@ -958,9 +957,9 @@ erts_bif_trace_epilogue(Process *p, Eterm result, int applying,
 		}
 	    }
 	    if ((flags_meta|flags) & MATCH_SET_EXCEPTION_TRACE) {
-		erts_smp_proc_lock(p, ERTS_PROC_LOCKS_ALL_MINOR);
+		erts_proc_lock(p, ERTS_PROC_LOCKS_ALL_MINOR);
 		ERTS_TRACE_FLAGS(p) |= F_EXCEPTION_TRACE;
-		erts_smp_proc_unlock(p, ERTS_PROC_LOCKS_ALL_MINOR);
+		erts_proc_unlock(p, ERTS_PROC_LOCKS_ALL_MINOR);
 	    }
 	}
     } else {
@@ -983,7 +982,7 @@ erts_bif_trace_epilogue(Process *p, Eterm result, int applying,
 	    }
 	}
     }
-    ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
+    ERTS_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
     return result;
 }
 
@@ -999,9 +998,9 @@ do_call_trace(Process* c_p, ErtsCodeInfo* info, Eterm* reg,
 
     fixup_cp_before_trace(c_p, &return_to_trace);
 
-    ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
+    ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
     flags = erts_call_trace(c_p, info, ms, reg, local, &tracer);
-    ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
+    ERTS_REQ_PROC_MAIN_LOCK(c_p);
 
     /* restore cp after potential fixup */
     c_p->cp = cp_save;
@@ -1041,9 +1040,9 @@ do_call_trace(Process* c_p, ErtsCodeInfo* info, Eterm* reg,
 				  the funcinfo is above i. */
 	c_p->cp = (flags & MATCH_SET_EXCEPTION_TRACE) ?
 	    beam_exception_trace : beam_return_trace;
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+	erts_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 	ERTS_TRACE_FLAGS(c_p) |= F_EXCEPTION_TRACE;
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
     } else
         c_p->stop = E;
     return tracer;
@@ -1060,7 +1059,7 @@ erts_trace_time_call(Process* c_p, ErtsCodeInfo *info, BpDataTime* bdt)
     Uint32 six = acquire_bp_sched_ix(c_p);
 
     ASSERT(c_p);
-    ASSERT(erts_smp_atomic32_read_acqb(&c_p->state) & (ERTS_PSFLG_RUNNING
+    ASSERT(erts_atomic32_read_acqb(&c_p->state) & (ERTS_PSFLG_RUNNING
 						       | ERTS_PSFLG_DIRTY_RUNNING));
 
     /* get previous timestamp and breakpoint
@@ -1141,7 +1140,7 @@ erts_trace_time_return(Process *p, ErtsCodeInfo *ci)
     Uint32 six = acquire_bp_sched_ix(p);
 
     ASSERT(p);
-    ASSERT(erts_smp_atomic32_read_acqb(&p->state) & (ERTS_PSFLG_RUNNING
+    ASSERT(erts_atomic32_read_acqb(&p->state) & (ERTS_PSFLG_RUNNING
 						     | ERTS_PSFLG_DIRTY_RUNNING));
 
     /* get previous timestamp and breakpoint
@@ -1223,7 +1222,7 @@ erts_is_mtrace_break(ErtsCodeInfo *ci, Binary **match_spec_ret,
 	    *match_spec_ret = bp->meta_ms;
 	}
 	if (tracer_ret) {
-            *tracer_ret = erts_smp_atomic_read_nob(&bp->meta_tracer->tracer);
+            *tracer_ret = erts_atomic_read_nob(&bp->meta_tracer->tracer);
 	}
 	return 1;
     }
@@ -1237,7 +1236,7 @@ erts_is_count_break(ErtsCodeInfo *ci, Uint *count_ret)
     
     if (bp) {
 	if (count_ret) {
-	    *count_ret = (Uint) erts_smp_atomic_read_nob(&bp->count->acount);
+	    *count_ret = (Uint) erts_atomic_read_nob(&bp->count->acount);
 	}
 	return 1;
     }
@@ -1318,7 +1317,7 @@ erts_find_local_func(ErtsCodeMFA *mfa) {
     n = (BeamInstr) code_hdr->num_functions;
     for (i = 0; i < n; ++i) {
 	ci = code_hdr->functions[i];
-	ASSERT(((BeamInstr) BeamOp(op_i_func_info_IaaI)) == ci->op);
+	ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
 	ASSERT(mfa->module == ci->mfa.module || is_nil(ci->mfa.module));
 	if (mfa->function == ci->mfa.function &&
 	    mfa->arity == ci->mfa.arity) {
@@ -1517,7 +1516,7 @@ set_function_break(ErtsCodeInfo *ci, Binary *match_spec, Uint break_flags,
     Uint common;
     ErtsBpIndex ix = erts_staging_bp_ix();
 
-    ERTS_SMP_LC_ASSERT(erts_has_code_write_permission());
+    ERTS_LC_ASSERT(erts_has_code_write_permission());
     g = ci->u.gen_bp;
     if (g == 0) {
 	int i;
@@ -1549,7 +1548,7 @@ set_function_break(ErtsCodeInfo *ci, Binary *match_spec, Uint break_flags,
 	    bp->flags &= ~ERTS_BPF_COUNT_ACTIVE;
 	} else {
 	    bp->flags |= ERTS_BPF_COUNT_ACTIVE;
-	    erts_smp_atomic_set_nob(&bp->count->acount, 0);
+	    erts_atomic_set_nob(&bp->count->acount, 0);
 	}
 	ASSERT((bp->flags & ~ERTS_BPF_ALL) == 0);
 	return;
@@ -1583,17 +1582,17 @@ set_function_break(ErtsCodeInfo *ci, Binary *match_spec, Uint break_flags,
 	MatchSetRef(match_spec);
 	bp->meta_ms = match_spec;
 	bmt = Alloc(sizeof(BpMetaTracer));
-	erts_smp_refc_init(&bmt->refc, 1);
+	erts_refc_init(&bmt->refc, 1);
         erts_tracer_update(&meta_tracer, tracer); /* copy tracer */
-	erts_smp_atomic_init_nob(&bmt->tracer, (erts_aint_t)meta_tracer);
+	erts_atomic_init_nob(&bmt->tracer, (erts_aint_t)meta_tracer);
 	bp->meta_tracer = bmt;
     } else if (break_flags & ERTS_BPF_COUNT) {
 	BpCount* bcp;
 
 	ASSERT((bp->flags & ERTS_BPF_COUNT) == 0);
 	bcp = Alloc(sizeof(BpCount));
-	erts_smp_refc_init(&bcp->refc, 1);
-	erts_smp_atomic_init_nob(&bcp->acount, 0);
+	erts_refc_init(&bcp->refc, 1);
+	erts_atomic_init_nob(&bcp->acount, 0);
 	bp->count = bcp;
     } else if (break_flags & ERTS_BPF_TIME_TRACE) {
 	BpDataTime* bdt;
@@ -1601,12 +1600,8 @@ set_function_break(ErtsCodeInfo *ci, Binary *match_spec, Uint break_flags,
 
 	ASSERT((bp->flags & ERTS_BPF_TIME_TRACE) == 0);
 	bdt = Alloc(sizeof(BpDataTime));
-	erts_smp_refc_init(&bdt->refc, 1);
-#ifdef ERTS_DIRTY_SCHEDULERS
+	erts_refc_init(&bdt->refc, 1);
 	bdt->n = erts_no_schedulers + 1;
-#else
-	bdt->n = erts_no_schedulers;
-#endif
 	bdt->hash = Alloc(sizeof(bp_time_hash_t)*(bdt->n));
 	for (i = 0; i < bdt->n; i++) {
 	    bp_hash_init(&(bdt->hash[i]), 32);
@@ -1638,7 +1633,7 @@ clear_function_break(ErtsCodeInfo *ci, Uint break_flags)
     Uint common;
     ErtsBpIndex ix = erts_staging_bp_ix();
 
-    ERTS_SMP_LC_ASSERT(erts_has_code_write_permission());
+    ERTS_LC_ASSERT(erts_has_code_write_permission());
 
     if ((g = ci->u.gen_bp) == NULL) {
 	return 1;
@@ -1671,8 +1666,8 @@ clear_function_break(ErtsCodeInfo *ci, Uint break_flags)
 static void
 bp_meta_unref(BpMetaTracer* bmt)
 {
-    if (erts_smp_refc_dectest(&bmt->refc, 0) <= 0) {
-        ErtsTracer trc = erts_smp_atomic_read_nob(&bmt->tracer);
+    if (erts_refc_dectest(&bmt->refc, 0) <= 0) {
+        ErtsTracer trc = erts_atomic_read_nob(&bmt->tracer);
         ERTS_TRACER_CLEAR(&trc);
 	Free(bmt);
     }
@@ -1681,7 +1676,7 @@ bp_meta_unref(BpMetaTracer* bmt)
 static void
 bp_count_unref(BpCount* bcp)
 {
-    if (erts_smp_refc_dectest(&bcp->refc, 0) <= 0) {
+    if (erts_refc_dectest(&bcp->refc, 0) <= 0) {
 	Free(bcp);
     }
 }
@@ -1689,7 +1684,7 @@ bp_count_unref(BpCount* bcp)
 static void
 bp_time_unref(BpDataTime* bdt)
 {
-    if (erts_smp_refc_dectest(&bdt->refc, 0) <= 0) {
+    if (erts_refc_dectest(&bdt->refc, 0) <= 0) {
 	Uint i = 0;
 	Uint j = 0;
 	Process *h_p = NULL;
@@ -1713,7 +1708,7 @@ bp_time_unref(BpDataTime* bdt)
 			    if (pbt) {
 				Free(pbt);
 			    }
-			    erts_smp_proc_unlock(h_p, ERTS_PROC_LOCK_MAIN);
+			    erts_proc_unlock(h_p, ERTS_PROC_LOCK_MAIN);
 			}
 		    }
 		}
@@ -1737,7 +1732,7 @@ check_break(ErtsCodeInfo *ci, Uint break_flags)
 {
     GenericBp* g = ci->u.gen_bp;
 
-    ASSERT(ci->op == (BeamInstr) BeamOp(op_i_func_info_IaaI));
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
     if (erts_is_function_native(ci)) {
 	return 0;
     }
diff --git a/erts/emulator/beam/beam_bp.h b/erts/emulator/beam/beam_bp.h
index 56fa82b912..a64765822b 100644
--- a/erts/emulator/beam/beam_bp.h
+++ b/erts/emulator/beam/beam_bp.h
@@ -41,7 +41,7 @@ typedef struct {
 typedef struct bp_data_time {     /* Call time */
     Uint n;
     bp_time_hash_t *hash;
-    erts_smp_refc_t refc;
+    erts_refc_t refc;
 } BpDataTime;
 
 typedef struct {
@@ -50,13 +50,13 @@ typedef struct {
 } process_breakpoint_time_t; /* used within psd */
 
 typedef struct {
-    erts_smp_atomic_t acount;
-    erts_smp_refc_t refc;
+    erts_atomic_t acount;
+    erts_refc_t refc;
 } BpCount;
 
 typedef struct {
-    erts_smp_atomic_t tracer;
-    erts_smp_refc_t refc;
+    erts_atomic_t tracer;
+    erts_refc_t refc;
 } BpMetaTracer;
 
 typedef struct generic_bp_data {
@@ -79,9 +79,7 @@ typedef struct generic_bp {
 #define ERTS_BP_CALL_TIME_SCHEDULE_OUT     (1)
 #define ERTS_BP_CALL_TIME_SCHEDULE_EXITING (2)
 
-#ifdef ERTS_DIRTY_SCHEDULERS
-extern erts_smp_mtx_t erts_dirty_bp_ix_mtx;
-#endif
+extern erts_mtx_t erts_dirty_bp_ix_mtx;
 
 enum erts_break_op{
     ERTS_BREAK_NOP   =  0, /* Must be false */
@@ -173,17 +171,17 @@ ErtsCodeInfo *erts_find_local_func(ErtsCodeMFA *mfa);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
-extern erts_smp_atomic32_t erts_active_bp_index;
-extern erts_smp_atomic32_t erts_staging_bp_index;
+extern erts_atomic32_t erts_active_bp_index;
+extern erts_atomic32_t erts_staging_bp_index;
 
 ERTS_GLB_INLINE ErtsBpIndex erts_active_bp_ix(void)
 {
-    return erts_smp_atomic32_read_nob(&erts_active_bp_index);
+    return erts_atomic32_read_nob(&erts_active_bp_index);
 }
 
 ERTS_GLB_INLINE ErtsBpIndex erts_staging_bp_ix(void)
 {
-    return erts_smp_atomic32_read_nob(&erts_staging_bp_index);
+    return erts_atomic32_read_nob(&erts_staging_bp_index);
 }
 #endif
 
diff --git a/erts/emulator/beam/beam_debug.c b/erts/emulator/beam/beam_debug.c
index a2060c80de..509aa2a84f 100644
--- a/erts/emulator/beam/beam_debug.c
+++ b/erts/emulator/beam/beam_debug.c
@@ -53,6 +53,8 @@ void dbg_where(BeamInstr* addr, Eterm x0, Eterm* reg);
 
 static int print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr);
 static void print_bif_name(fmtfn_t to, void* to_arg, BifFunction bif);
+static BeamInstr* f_to_addr(BeamInstr* base, int op, BeamInstr* ap);
+static BeamInstr* f_to_addr_packed(BeamInstr* base, int op, Sint32* ap);
 
 BIF_RETTYPE
 erts_debug_same_2(BIF_ALIST_2)
@@ -157,8 +159,8 @@ erts_debug_breakpoint_2(BIF_ALIST_2)
 	ERTS_BIF_YIELD2(bif_export[BIF_erts_debug_breakpoint_2],
 			BIF_P, BIF_ARG_1, BIF_ARG_2);
     }
-    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
-    erts_smp_thr_progress_block();
+    erts_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
+    erts_thr_progress_block();
 
     erts_bp_match_functions(&f, &mfa, specified);
     if (boolean == am_true) {
@@ -174,8 +176,8 @@ erts_debug_breakpoint_2(BIF_ALIST_2)
     res = make_small(f.matched);
     erts_bp_free_matched_functions(&f);
 
-    erts_smp_thr_progress_unblock();
-    erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
+    erts_thr_progress_unblock();
+    erts_proc_lock(p, ERTS_PROC_LOCK_MAIN);
     erts_release_code_write_permission();
     return res;
 
@@ -197,9 +199,9 @@ void debug_dump_code(BeamInstr *I, int num)
 	erts_print(ERTS_PRINT_DSBUF, (void *) dsbufp, HEXF ": ", code_ptr);
 	instr = (BeamInstr) code_ptr[0];
 	for (i = 0; i < NUM_SPECIFIC_OPS; i++) {
-	    if (instr == (BeamInstr) BeamOp(i) && opc[i].name[0] != '\0') {
+	    if (BeamIsOpCode(instr, i) && opc[i].name[0] != '\0') {
 		code_ptr += print_op(ERTS_PRINT_DSBUF, (void *) dsbufp,
-				     i, opc[i].sz-1, code_ptr+1) + 1;
+				     i, opc[i].sz-1, code_ptr) + 1;
 		break;
 	    }
 	}
@@ -317,9 +319,9 @@ erts_debug_disassemble_1(BIF_ALIST_1)
     erts_print(ERTS_PRINT_DSBUF, (void *) dsbufp, HEXF ": ", code_ptr);
     instr = (BeamInstr) code_ptr[0];
     for (i = 0; i < NUM_SPECIFIC_OPS; i++) {
-	if (instr == (BeamInstr) BeamOp(i) && opc[i].name[0] != '\0') {
+	if (BeamIsOpCode(instr, i) && opc[i].name[0] != '\0') {
 	    code_ptr += print_op(ERTS_PRINT_DSBUF, (void *) dsbufp,
-				 i, opc[i].sz-1, code_ptr+1) + 1;
+				 i, opc[i].sz-1, code_ptr) + 1;
 	    break;
 	}
     }
@@ -403,8 +405,14 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
 	 * Avoid copying because instructions containing bignum operands
 	 * are bigger than actually declared.
 	 */
-	ap = (BeamInstr *) addr;
+        addr++;
+        ap = addr;
     } else {
+#if defined(ARCH_64) && defined(CODE_MODEL_SMALL)
+        BeamInstr instr_word = addr[0];
+#endif
+        addr++;
+
 	/*
 	 * Copy all arguments to a local buffer for the unpacking.
 	 */
@@ -424,26 +432,27 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
 	while (start_prog < prog) {
 	    prog--;
 	    switch (*prog) {
+	    case 'f':
 	    case 'g':
+	    case 'q':
 		*ap++ = *--sp;
 		break;
-	    case 'i':		/* Initialize packing accumulator. */
-		*ap++ = packed;
-		break;
-	    case 's':
-		*ap++ = packed & 0x3ff;
-		packed >>= 10;
+#ifdef ARCH_64
+	    case '1':		/* Tightest shift */
+		*ap++ = (packed & BEAM_TIGHTEST_MASK) << 3;
+		packed >>= BEAM_TIGHTEST_SHIFT;
 		break;
-	    case '0':		/* Tight shift */
+#endif
+	    case '2':		/* Tight shift */
 		*ap++ = packed & BEAM_TIGHT_MASK;
 		packed >>= BEAM_TIGHT_SHIFT;
 		break;
-	    case '6':		/* Shift 16 steps */
+	    case '3':		/* Loose shift */
 		*ap++ = packed & BEAM_LOOSE_MASK;
 		packed >>= BEAM_LOOSE_SHIFT;
 		break;
 #ifdef ARCH_64
-	    case 'w':		/* Shift 32 steps */
+	    case '4':		/* Shift 32 steps */
 		*ap++ = packed & BEAM_WIDE_MASK;
 		packed >>= BEAM_WIDE_SHIFT;
 		break;
@@ -454,8 +463,18 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
 	    case 'P':
 		packed = *--sp;
 		break;
+#if defined(ARCH_64) && defined(CODE_MODEL_SMALL)
+            case '#':       /* -1 */
+            case '$':       /* -2 */
+            case '%':       /* -3 */
+            case '&':       /* -4 */
+            case '\'':      /* -5 */
+            case '(':       /* -6 */
+                packed = (packed << BEAM_WIDE_SHIFT) | BeamExtraData(instr_word);
+		break;
+#endif
 	    default:
-		ASSERT(0);
+                erts_exit(ERTS_ERROR_EXIT, "beam_debug: invalid packing op: %c\n", *prog);
 	    }
 	}
 	ap = args;
@@ -489,6 +508,14 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
 	case 'n':		/* Nil */
 	    erts_print(to, to_arg, "[]");
 	    break;
+        case 'S':               /* Register */
+            {
+                Uint reg_type = (*ap & 1) ? 'y' : 'x';
+                Uint n = ap[0] / sizeof(Eterm);
+                erts_print(to, to_arg, "%c(%d)", reg_type, n);
+		ap++;
+                break;
+            }
 	case 's':		/* Any source (tagged constant or register) */
 	    tag = loader_tag(*ap);
 	    if (tag == LOADER_X_REG) {
@@ -522,12 +549,13 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
 	    }
 	    ap++;
 	    break;
-	case 'I':		/* Untagged integer. */
-	case 't':
+	case 't':               /* Untagged integers */
+	case 'I':
+        case 'W':
 	    switch (op) {
-	    case op_i_gc_bif1_jIsId:
-	    case op_i_gc_bif2_jIIssd:
-	    case op_i_gc_bif3_jIIssd:
+	    case op_i_gc_bif1_jWstd:
+	    case op_i_gc_bif2_jWtssd:
+	    case op_i_gc_bif3_jWtssd:
 		{
 		    const ErtsGcBif* p;
 		    BifFunction gcf = (BifFunction) *ap;
@@ -549,9 +577,10 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
 	    break;
 	case 'f':		/* Destination label */
 	    {
-		ErtsCodeMFA* cmfa = find_function_from_pc((BeamInstr *)*ap);
-		if (!cmfa || erts_codemfa_to_code(cmfa) != (BeamInstr *) *ap) {
-		    erts_print(to, to_arg, "f(" HEXF ")", *ap);
+                BeamInstr* target = f_to_addr(addr, op, ap);
+		ErtsCodeMFA* cmfa = find_function_from_pc(target);
+		if (!cmfa || erts_codemfa_to_code(cmfa) != target) {
+		    erts_print(to, to_arg, "f(" HEXF ")", target);
 		} else {
 		    erts_print(to, to_arg, "%T:%T/%bpu", cmfa->module,
                                cmfa->function, cmfa->arity);
@@ -561,18 +590,18 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
 	    break;
 	case 'p':		/* Pointer (to label) */
 	    {
-		ErtsCodeMFA* cmfa = find_function_from_pc((BeamInstr *)*ap);
-		if (!cmfa || erts_codemfa_to_code(cmfa) != (BeamInstr *) *ap) {
-		    erts_print(to, to_arg, "p(" HEXF ")", *ap);
-		} else {
-		    erts_print(to, to_arg, "%T:%T/%bpu", cmfa->module,
-                               cmfa->function, cmfa->arity);
-		}
+                BeamInstr* target = f_to_addr(addr, op, ap);
+                erts_print(to, to_arg, "p(" HEXF ")", target);
 		ap++;
 	    }
 	    break;
 	case 'j':		/* Pointer (to label) */
-	    erts_print(to, to_arg, "j(" HEXF ")", *ap);
+            if (*ap == 0) {
+                erts_print(to, to_arg, "j(0)");
+            } else {
+                BeamInstr* target = f_to_addr(addr, op, ap);
+                erts_print(to, to_arg, "j(" HEXF ")", target);
+            }
 	    ap++;
 	    break;
 	case 'e':		/* Export entry */
@@ -615,12 +644,22 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
 
     unpacked = ap;
     ap = addr + size;
+
+    /*
+     * In the code below, never use ap[-1], ap[-2], ...
+     * (will not work if the arguments have been packed).
+     *
+     * Instead use unpacked[-1], unpacked[-2], ...
+     */
     switch (op) {
     case op_i_select_val_lins_xfI:
     case op_i_select_val_lins_yfI:
+    case op_i_select_val_bins_xfI:
+    case op_i_select_val_bins_yfI:
 	{
-	    int n = ap[-1];
+	    int n = unpacked[-1];
 	    int ix = n;
+            Sint32* jump_tab = (Sint32 *)(ap + n);
 
 	    while (ix--) {
 		erts_print(to, to_arg, "%T ", (Eterm) ap[0]);
@@ -629,30 +668,19 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
 	    }
 	    ix = n;
 	    while (ix--) {
-		erts_print(to, to_arg, "f(" HEXF ") ", (Eterm) ap[0]);
-		ap++;
-		size++;
-	    }
-	}
-	break;
-    case op_i_select_val_bins_xfI:
-    case op_i_select_val_bins_yfI:
-	{
-	    int n = ap[-1];
-
-	    while (n > 0) {
-		erts_print(to, to_arg, "%T f(" HEXF ") ", (Eterm) ap[0], ap[1]);
-		ap += 2;
-		size += 2;
-		n--;
+                BeamInstr* target = f_to_addr_packed(addr, op, jump_tab);
+		erts_print(to, to_arg, "f(" HEXF ") ", target);
+                jump_tab++;
 	    }
+            size += (n+1) / 2;
 	}
 	break;
     case op_i_select_tuple_arity_xfI:
     case op_i_select_tuple_arity_yfI:
         {
-            int n = ap[-1];
+            int n = unpacked[-1];
             int ix = n - 1; /* without sentinel */
+            Sint32* jump_tab = (Sint32 *)(ap + n);
 
             while (ix--) {
                 Uint arity = arityval(ap[0]);
@@ -666,39 +694,62 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
             size++;
             ix = n;
             while (ix--) {
-                erts_print(to, to_arg, "f(" HEXF ") ", ap[0]);
-                ap++;
-                size++;
+                BeamInstr* target = f_to_addr_packed(addr, op, jump_tab);
+                erts_print(to, to_arg, "f(" HEXF ") ", target);
+                jump_tab++;
             }
+            size += (n+1) / 2;
         }
         break;
-    case op_i_jump_on_val_xfII:
-    case op_i_jump_on_val_yfII:
+    case op_i_select_val2_xfcc:
+    case op_i_select_val2_yfcc:
+    case op_i_select_tuple_arity2_xfAA:
+    case op_i_select_tuple_arity2_yfAA:
+        {
+            Sint32* jump_tab = (Sint32 *) ap;
+            BeamInstr* target;
+            int i;
+
+            for (i = 0; i < 2; i++) {
+                target = f_to_addr_packed(addr, op, jump_tab++);
+                erts_print(to, to_arg, "f(" HEXF ") ", target);
+            }
+            size += 1;
+        }
+        break;
+    case op_i_jump_on_val_xfIW:
+    case op_i_jump_on_val_yfIW:
 	{
-	    int n;
-	    for (n = ap[-2]; n > 0; n--) {
-		erts_print(to, to_arg, "f(" HEXF ") ", ap[0]);
-		ap++;
-		size++;
+	    int n = unpacked[-2];
+            Sint32* jump_tab = (Sint32 *) ap;
+
+            size += (n+1) / 2;
+            while (n-- > 0) {
+                BeamInstr* target = f_to_addr_packed(addr, op, jump_tab);
+		erts_print(to, to_arg, "f(" HEXF ") ", target);
+                jump_tab++;
 	    }
 	}
 	break;
     case op_i_jump_on_val_zero_xfI:
     case op_i_jump_on_val_zero_yfI:
 	{
-	    int n;
-	    for (n = ap[-1]; n > 0; n--) {
-		erts_print(to, to_arg, "f(" HEXF ") ", ap[0]);
-		ap++;
-		size++;
+	    int n = unpacked[-1];
+            Sint32* jump_tab = (Sint32 *) ap;
+
+            size += (n+1) / 2;
+            while (n-- > 0) {
+                BeamInstr* target = f_to_addr_packed(addr, op, jump_tab);
+		erts_print(to, to_arg, "f(" HEXF ") ", target);
+                jump_tab++;
 	    }
 	}
 	break;
     case op_i_put_tuple_xI:
     case op_i_put_tuple_yI:
-    case op_new_map_dII:
-    case op_update_map_assoc_jsdII:
-    case op_update_map_exact_jsdII:
+    case op_new_map_dtI:
+    case op_update_map_assoc_sdtI:
+    case op_update_map_exact_jsdtI:
 	{
 	    int n = unpacked[-1];
 
@@ -708,7 +759,7 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
 		    erts_print(to, to_arg, " x(%d)", loader_x_reg_index(ap[0]));
 		    break;
 		case LOADER_Y_REG:
-		    erts_print(to, to_arg, " x(%d)", loader_y_reg_index(ap[0]));
+		    erts_print(to, to_arg, " y(%d)", loader_y_reg_index(ap[0]) - CP_SIZE);
 		    break;
 		default:
 		    erts_print(to, to_arg, " %T", (Eterm) ap[0]);
@@ -718,6 +769,27 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
 	    }
 	}
 	break;
+    case op_i_new_small_map_lit_dtq:
+        {
+            Eterm *tp = tuple_val(unpacked[-1]);
+            int n = arityval(*tp);
+
+            while (n > 0) {
+                switch (loader_tag(ap[0])) {
+                case LOADER_X_REG:
+                    erts_print(to, to_arg, " x(%d)", loader_x_reg_index(ap[0]));
+                    break;
+                case LOADER_Y_REG:
+		    erts_print(to, to_arg, " y(%d)", loader_y_reg_index(ap[0]) - CP_SIZE);
+		    break;
+                default:
+		    erts_print(to, to_arg, " %T", (Eterm) ap[0]);
+		    break;
+                }
+                ap++, size++, n--;
+            }
+        }
+        break;
     case op_i_get_map_elements_fsI:
 	{
 	    int n = unpacked[-1];
@@ -731,7 +803,7 @@ print_op(fmtfn_t to, void *to_arg, int op, int size, BeamInstr* addr)
 			erts_print(to, to_arg, " x(%d)", loader_x_reg_index(ap[0]));
 			break;
 		    case LOADER_Y_REG:
-			erts_print(to, to_arg, " y(%d)", loader_y_reg_index(ap[0]));
+			erts_print(to, to_arg, " y(%d)", loader_y_reg_index(ap[0]) - CP_SIZE);
 			break;
 		    default:
 			erts_print(to, to_arg, " %T", (Eterm) ap[0]);
@@ -766,6 +838,17 @@ static void print_bif_name(fmtfn_t to, void* to_arg, BifFunction bif)
     }
 }
 
+static BeamInstr* f_to_addr(BeamInstr* base, int op, BeamInstr* ap)
+{
+    return base - 1 + opc[op].adjust + (Sint32) *ap;
+}
+
+static BeamInstr* f_to_addr_packed(BeamInstr* base, int op, Sint32* ap)
+{
+    return base - 1 + opc[op].adjust + *ap;
+}
+
+
 /*
  * Dirty BIF testing.
  *
@@ -774,10 +857,8 @@ static void print_bif_name(fmtfn_t to, void* to_arg, BifFunction bif)
  * test suite.
  */
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 static int ms_wait(Process *c_p, Eterm etimeout, int busy);
 static int dirty_send_message(Process *c_p, Eterm to, Eterm tag);
-#endif
 static BIF_RETTYPE dirty_test(Process *c_p, Eterm type, Eterm arg1, Eterm arg2, UWord *I);
 
 /*
@@ -806,7 +887,6 @@ erts_debug_dirty_io_2(BIF_ALIST_2)
 BIF_RETTYPE
 erts_debug_dirty_3(BIF_ALIST_3)
 {
-#ifdef ERTS_DIRTY_SCHEDULERS
     Eterm argv[2];
     switch (BIF_ARG_1) {
     case am_normal:
@@ -836,9 +916,6 @@ erts_debug_dirty_3(BIF_ALIST_3)
     default:
 	BIF_ERROR(BIF_P, EXC_BADARG);
     }
-#else
-	BIF_ERROR(BIF_P, EXC_UNDEF);
-#endif
 }
 
 
@@ -846,7 +923,6 @@ static BIF_RETTYPE
 dirty_test(Process *c_p, Eterm type, Eterm arg1, Eterm arg2, UWord *I)
 {
     BIF_RETTYPE ret;
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (am_scheduler == arg1) {
 	ErtsSchedulerData *esdp;
 	if (arg2 != am_type) 
@@ -1032,13 +1108,9 @@ dirty_test(Process *c_p, Eterm type, Eterm arg1, Eterm arg2, UWord *I)
     badarg:
 	ERTS_BIF_PREP_ERROR(ret, c_p, BADARG);
     }
-#else
-    ERTS_BIF_PREP_ERROR(ret, c_p, EXC_UNDEF);
-#endif
     return ret;
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 static int
 dirty_send_message(Process *c_p, Eterm to, Eterm tag)
@@ -1075,7 +1147,7 @@ dirty_send_message(Process *c_p, Eterm to, Eterm tag)
     if (rp == real_c_p)
 	rp_locks &= ~c_p_locks;
     if (rp_locks)
-	erts_smp_proc_unlock(rp, rp_locks);
+	erts_proc_unlock(rp, rp_locks);
 
     erts_proc_dec_refc(rp);
 
@@ -1125,13 +1197,8 @@ ms_wait(Process *c_p, Eterm etimeout, int busy)
     return 1;
 }
 
-#endif /* ERTS_DIRTY_SCHEDULERS */
 
-#ifdef ERTS_SMP
 #  define ERTS_STACK_LIMIT ((char *) ethr_get_stacklimit())
-#else
-#  define ERTS_STACK_LIMIT ((char *) erts_scheduler_stack_limit)
-#endif
 
 /*
  * The below functions is for testing of the stack
diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c
index b4e6c35579..ef9abcde08 100644
--- a/erts/emulator/beam/beam_emu.c
+++ b/erts/emulator/beam/beam_emu.c
@@ -50,45 +50,40 @@
 #if defined(NO_JUMP_TABLE)
 #  define OpCase(OpCode)    case op_##OpCode
 #  define CountCase(OpCode) case op_count_##OpCode
-#  define OpCode(OpCode)    ((Uint*)op_##OpCode)
-#  define Goto(Rel) {Go = (int)(UWord)(Rel); goto emulator_loop;}
-#  define LabelAddr(Addr) &&##Addr
+#  define IsOpCode(InstrWord, OpCode)  (BeamCodeAddr(InstrWord) == (BeamInstr)op_##OpCode)
+#  define Goto(Rel)         {Go = BeamCodeAddr(Rel); goto emulator_loop;}
+#  define GotoPF(Rel)       Goto(Rel)
 #else
 #  define OpCase(OpCode)    lb_##OpCode
 #  define CountCase(OpCode) lb_count_##OpCode
-#  define Goto(Rel) goto *((void *)Rel)
-#  define LabelAddr(Label) &&Label
-#  define OpCode(OpCode)  (&&lb_##OpCode)
+#  define IsOpCode(InstrWord, OpCode)  (BeamCodeAddr(InstrWord) == (BeamInstr)&&lb_##OpCode)
+#  define Goto(Rel)         goto *((void *)BeamCodeAddr(Rel))
+#  define GotoPF(Rel)       goto *((void *)Rel)
+#  define LabelAddr(Label)  &&Label
 #endif
 
 #ifdef ERTS_ENABLE_LOCK_CHECK
-#  ifdef ERTS_SMP
-#    define PROCESS_MAIN_CHK_LOCKS(P)					\
-do {									\
-    if ((P))								\
-	erts_proc_lc_chk_only_proc_main((P));				\
-    ERTS_SMP_LC_ASSERT(!erts_thr_progress_is_blocking());		\
+#    define PROCESS_MAIN_CHK_LOCKS(P)                   \
+do {                                                    \
+    if ((P))                                            \
+	erts_proc_lc_chk_only_proc_main((P));           \
+    ERTS_LC_ASSERT(!erts_thr_progress_is_blocking());   \
 } while (0)
-#    define ERTS_SMP_REQ_PROC_MAIN_LOCK(P)				\
-do {									\
-    if ((P))								\
-	erts_proc_lc_require_lock((P), ERTS_PROC_LOCK_MAIN,		\
-				  __FILE__, __LINE__);			\
+#    define ERTS_REQ_PROC_MAIN_LOCK(P)				\
+do {                                                            \
+    if ((P))                                                    \
+	erts_proc_lc_require_lock((P), ERTS_PROC_LOCK_MAIN,     \
+				  __FILE__, __LINE__);          \
 } while (0)
-#    define ERTS_SMP_UNREQ_PROC_MAIN_LOCK(P)				\
+#    define ERTS_UNREQ_PROC_MAIN_LOCK(P)				\
 do {									\
     if ((P))								\
 	erts_proc_lc_unrequire_lock((P), ERTS_PROC_LOCK_MAIN);		\
 } while (0)
-#  else
-#    define ERTS_SMP_REQ_PROC_MAIN_LOCK(P)
-#    define ERTS_SMP_UNREQ_PROC_MAIN_LOCK(P)
-#    define PROCESS_MAIN_CHK_LOCKS(P) erts_lc_check_exact(NULL, 0)
-#  endif
 #else
 #  define PROCESS_MAIN_CHK_LOCKS(P)
-#  define ERTS_SMP_REQ_PROC_MAIN_LOCK(P)
-#  define ERTS_SMP_UNREQ_PROC_MAIN_LOCK(P)
+#  define ERTS_REQ_PROC_MAIN_LOCK(P)
+#  define ERTS_UNREQ_PROC_MAIN_LOCK(P)
 #endif
 
 /*
@@ -113,6 +108,8 @@ do {                                     \
 #  define CHECK_ARGS(T)
 #endif
 
+#define CHECK_ALIGNED(Dst) ASSERT((((Uint)&Dst) & (sizeof(Uint)-1)) == 0)
+
 #define GET_BIF_MODULE(p)  (p->info.mfa.module)
 #define GET_BIF_FUNCTION(p)  (p->info.mfa.function)
 #define GET_BIF_ARITY(p)  (p->info.mfa.arity)
@@ -136,11 +133,11 @@ do {                                     \
 
 /* We don't check the range if an ordinary switch is used */
 #ifdef NO_JUMP_TABLE
-#define VALID_INSTR(IP) ((UWord)(IP) < (NUMBER_OF_OPCODES*2+10))
+#  define VALID_INSTR(IP) (BeamCodeAddr(IP) < (NUMBER_OF_OPCODES*2+10))
 #else
-#define VALID_INSTR(IP) \
-   ((SWord)LabelAddr(emulator_loop) <= (SWord)(IP) && \
-    (SWord)(IP) < (SWord)LabelAddr(end_emulator_loop))
+#  define VALID_INSTR(IP) \
+    ((BeamInstr)LabelAddr(emulator_loop) <= BeamCodeAddr(IP) && \
+     BeamCodeAddr(IP) < (BeamInstr)LabelAddr(end_emulator_loop))
 #endif /* NO_JUMP_TABLE */
 
 #define SET_CP(p, ip)           \
@@ -155,50 +152,7 @@ do {                                     \
  * Register target (X or Y register).
  */
 
-#define REG_TARGET_PTR(Target) (((Target) & 1) ? &yb(Target-1) : &xb(Target))
-#define REG_TARGET(Target) (*REG_TARGET_PTR(Target))
-
-/*
- * Store a result into a register given a destination descriptor.
- */
-
-#define StoreResult(Result, DestDesc)		\
-  do {						\
-    Eterm stb_reg;				\
-    stb_reg = (DestDesc);			\
-    CHECK_TERM(Result);				\
-    REG_TARGET(stb_reg) = (Result);		\
-  } while (0)
-
-/*
- * Store a result into a register and execute the next instruction.
- * Dst points to the word with a destination descriptor, which MUST
- * be just before the next instruction.
- */
- 
-#define StoreBifResult(Dst, Result)		\
-  do {						\
-    BeamInstr* stb_next;			\
-    Eterm stb_reg;				\
-    stb_reg = Arg(Dst);				\
-    I += (Dst) + 2;				\
-    stb_next = (BeamInstr *) *I;		\
-    CHECK_TERM(Result);				\
-    REG_TARGET(stb_reg) = (Result);		\
-    Goto(stb_next);				\
-  } while (0)
-
-#define ClauseFail() goto jump_f
-
-#define SAVE_CP(X)				\
-   do {						\
-      *(X) = make_cp(c_p->cp);			\
-      c_p->cp = 0;				\
-   } while(0)
-
-#define RESTORE_CP(X)		SET_CP(c_p, (BeamInstr *) cp_val(*(X)))
-
-#define ISCATCHEND(instr) ((Eterm *) *(instr) == OpCode(catch_end_y))
+#define REG_TARGET_PTR(Target) (((Target) & 1) ? &yb((Target)-1) : &xb(Target))
 
 /*
  * Special Beam instructions.
@@ -208,11 +162,6 @@ BeamInstr beam_apply[2];
 BeamInstr beam_exit[1];
 BeamInstr beam_continue_exit[1];
 
-BeamInstr* em_call_error_handler;
-BeamInstr* em_apply_bif;
-BeamInstr* em_call_nif;
-BeamInstr* em_call_bif_e;
-
 
 /* NOTE These should be the only variables containing trace instructions.
 **      Sometimes tests are form the instruction value, and sometimes
@@ -281,163 +230,24 @@ void** beam_ops;
      HEAP_TOP((P)) = HTOP;  						\
      (P)->stop = E;  							\
      PROCESS_MAIN_CHK_LOCKS((P));					\
-     ERTS_SMP_UNREQ_PROC_MAIN_LOCK((P))
+     ERTS_UNREQ_PROC_MAIN_LOCK((P))
 
 #define db(N) (N)
+#define fb(N) ((Sint)(Sint32)(N))
+#define jb(N) ((Sint)(Sint32)(N))
 #define tb(N) (N)
-#define xb(N) (*(Eterm *) (((unsigned char *)reg) + (N)))
-#define yb(N) (*(Eterm *) (((unsigned char *)E) + (N)))
-#define fb(N) (*(double *) (((unsigned char *)&(freg[0].fd)) + (N)))
+#define xb(N) (*ADD_BYTE_OFFSET(reg, N))
+#define yb(N) (*ADD_BYTE_OFFSET(E, N))
+#define Sb(N) (*REG_TARGET_PTR(N))
+#define lb(N) (*(double *) (((unsigned char *)&(freg[0].fd)) + (N)))
 #define Qb(N) (N)
 #define Ib(N) (N)
+
 #define x(N) reg[N]
 #define y(N) E[N]
 #define r(N) x(N)
-
-/*
- * Makes sure that there are StackNeed + HeapNeed + 1 words available
- * on the combined heap/stack segment, then allocates StackNeed + 1
- * words on the stack and saves CP.
- *
- * M is number of live registers to preserve during garbage collection
- */
-
-#define AH(StackNeed, HeapNeed, M) \
-  do { \
-     int needed; \
-     needed = (StackNeed) + 1; \
-     if (E - HTOP < (needed + (HeapNeed))) { \
-           SWAPOUT; \
-           PROCESS_MAIN_CHK_LOCKS(c_p); \
-           FCALLS -= erts_garbage_collect_nobump(c_p, needed + (HeapNeed), \
-						 reg, (M), FCALLS);	\
-           ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p); \
-           PROCESS_MAIN_CHK_LOCKS(c_p); \
-           SWAPIN; \
-     } \
-     E -= needed; \
-     SAVE_CP(E); \
-  } while (0)
-
-#define Allocate(Ns, Live) AH(Ns, 0, Live)
-
-#define AllocateZero(Ns, Live)             \
- do { Eterm* ptr;                          \
-      int i = (Ns);                        \
-      AH(i, 0, Live);                      \
-      for (ptr = E + i; ptr > E; ptr--) {  \
-	 make_blank(*ptr);                 \
-     }                                     \
-  } while (0)
-
-#define AllocateHeap(Ns, Nh, Live) AH(Ns, Nh, Live)
-
-#define AllocateHeapZero(Ns, Nh, Live)     \
- do { Eterm* ptr;                          \
-      int i = (Ns);                        \
-      AH(i, Nh, Live);                     \
-      for (ptr = E + i; ptr > E; ptr--) {  \
-	 make_blank(*ptr);                 \
-     }                                     \
-  } while (0)
-
-#define AllocateInit(Ns, Live, Y) \
-  do { AH(Ns, 0, Live); make_blank(Y); } while (0)
-
-/*
- * Like the AH macro, but allocates no additional heap space.
- */
-
-#define A(StackNeed, M) AH(StackNeed, 0, M)
-
-#define D(N)             \
-     RESTORE_CP(E);      \
-     E += (N) + 1;
-
-
-
-#define TestBinVHeap(VNh, Nh, Live)                             		\
-  do {                                                          		\
-    unsigned need = (Nh);                                       		\
-    if ((E - HTOP < need) || (MSO(c_p).overhead + (VNh) >= BIN_VHEAP_SZ(c_p))) {\
-       SWAPOUT;                                                 		\
-       PROCESS_MAIN_CHK_LOCKS(c_p);                             		\
-       FCALLS -= erts_garbage_collect_nobump(c_p, need, reg, (Live), FCALLS);	\
-       ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);					\
-       PROCESS_MAIN_CHK_LOCKS(c_p);                             		\
-       SWAPIN;                                                  		\
-    }                                                           		\
-    HEAP_SPACE_VERIFIED(need);                                                  \
-  } while (0)
-
-
-
-/*
- * Check if Nh words of heap are available; if not, do a garbage collection.
- * Live is number of active argument registers to be preserved.
- */
-
-#define TestHeap(Nh, Live)                                      \
-  do {                                                          \
-    unsigned need = (Nh);                                       \
-    if (E - HTOP < need) {                                      \
-       SWAPOUT;                                                 \
-       PROCESS_MAIN_CHK_LOCKS(c_p);                             \
-       FCALLS -= erts_garbage_collect_nobump(c_p, need, reg, (Live), FCALLS); \
-       ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);			\
-       PROCESS_MAIN_CHK_LOCKS(c_p);                             \
-       SWAPIN;                                                  \
-    }                                                           \
-    HEAP_SPACE_VERIFIED(need);                             \
-  } while (0)
-
-/*
- * Check if Nh words of heap are available; if not, do a garbage collection.
- * Live is number of active argument registers to be preserved.
- * Takes special care to preserve Extra if a garbage collection occurs.
- */
-
-#define TestHeapPreserve(Nh, Live, Extra)				\
-  do {									\
-    unsigned need = (Nh);						\
-    if (E - HTOP < need) {						\
-       SWAPOUT;								\
-       reg[Live] = Extra;						\
-       PROCESS_MAIN_CHK_LOCKS(c_p);					\
-       FCALLS -= erts_garbage_collect_nobump(c_p, need, reg, (Live)+1, FCALLS); \
-       ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);				\
-       PROCESS_MAIN_CHK_LOCKS(c_p);					\
-       Extra = reg[Live];						\
-       SWAPIN;								\
-    }									\
-    HEAP_SPACE_VERIFIED(need);                                      \
-  } while (0)
-
-#define TestHeapPutList(Need, Reg)		\
-  do {						\
-     TestHeap((Need), 1);			\
-     PutList(Reg, r(0), r(0));                  \
-     CHECK_TERM(r(0));				\
-  } while (0)
-
-#define Init(N) make_blank(yb(N))
-
-#define Init2(Y1, Y2) do { make_blank(Y1); make_blank(Y2); } while (0)
-#define Init3(Y1, Y2, Y3) \
-   do { make_blank(Y1); make_blank(Y2); make_blank(Y3); } while (0)
-
-#define MakeFun(FunP, NumFree)					\
-  do {								\
-     HEAVY_SWAPOUT;						\
-     r(0) = new_fun(c_p, reg, (ErlFunEntry *) FunP, NumFree);	\
-     HEAVY_SWAPIN;						\
-  } while (0)
-
-#define PutTuple(Dst, Arity)			\
- do {						\
-   Dst = make_tuple(HTOP);			\
-   pt_arity = (Arity);				\
- } while (0)
+#define Q(N) (N*sizeof(Eterm *))
+#define l(N) (freg[N].fd)
 
 /*
  * Check that we haven't used the reductions and jump to function pointed to by
@@ -446,8 +256,8 @@ void** beam_ops;
 
 #define DispatchMacro()				\
   do {						\
-     BeamInstr* dis_next;				\
-     dis_next = (BeamInstr *) *I;			\
+     BeamInstr dis_next;                        \
+     dis_next = *I;                             \
      CHECK_ARGS(I);				\
      if (FCALLS > 0 || FCALLS > neg_o_reds) {	\
         FCALLS--;				\
@@ -455,12 +265,12 @@ void** beam_ops;
      } else {					\
 	goto context_switch;			\
      }						\
- } while (0)
+ } while (0)                                    \
 
 #define DispatchMacroFun()			\
   do {						\
-     BeamInstr* dis_next;				\
-     dis_next = (BeamInstr *) *I;			\
+     BeamInstr dis_next;                        \
+     dis_next = *I;                             \
      CHECK_ARGS(I);				\
      if (FCALLS > 0 || FCALLS > neg_o_reds) {	\
         FCALLS--;				\
@@ -470,23 +280,23 @@ void** beam_ops;
      }						\
  } while (0)
 
-#define DispatchMacrox()					\
-  do {								\
-     if (FCALLS > 0) {						\
-        Eterm* dis_next;					\
-        SET_I(((Export *) Arg(0))->addressv[erts_active_code_ix()]); \
-        dis_next = (Eterm *) *I;				\
-        FCALLS--;						\
-        CHECK_ARGS(I);						\
-        Goto(dis_next);						\
-     } else if (ERTS_PROC_GET_SAVED_CALLS_BUF(c_p)		\
-		&& FCALLS > neg_o_reds) {			\
-        goto save_calls1;					\
-     } else {							\
-        SET_I(((Export *) Arg(0))->addressv[erts_active_code_ix()]); \
-        CHECK_ARGS(I);						\
-	goto context_switch;					\
-     }								\
+#define DispatchMacrox()                                                \
+  do {                                                                  \
+     if (FCALLS > 0) {                                                  \
+        BeamInstr dis_next;                                             \
+        SET_I(((Export *) Arg(0))->addressv[erts_active_code_ix()]);    \
+        dis_next = *I;                                                  \
+        FCALLS--;                                                       \
+        CHECK_ARGS(I);                                                  \
+        Goto(dis_next);                                                 \
+     } else if (ERTS_PROC_GET_SAVED_CALLS_BUF(c_p)                      \
+		&& FCALLS > neg_o_reds) {                               \
+        goto save_calls1;                                               \
+     } else {                                                           \
+        SET_I(((Export *) Arg(0))->addressv[erts_active_code_ix()]);    \
+        CHECK_ARGS(I);                                                  \
+	goto context_switch;                                            \
+     }                                                                  \
  } while (0)
 
 #ifdef DEBUG
@@ -505,20 +315,7 @@ void** beam_ops;
 #  define Dispatchfun() DispatchMacroFun()
 #endif
 
-#define Self(R) R = c_p->common.id
-#define Node(R) R = erts_this_node->sysname
-
 #define Arg(N)       I[(N)+1]
-#define Next(N)                \
-    I += (N) + 1;              \
-    ASSERT(VALID_INSTR(*I));   \
-    Goto(*I)
-
-#define PreFetch(N, Dst) do { Dst = (BeamInstr *) *(I + N + 1); } while (0)
-#define NextPF(N, Dst)         \
-    I += N + 1;                \
-    ASSERT(VALID_INSTR(Dst));  \
-    Goto(Dst)
 
 #define GetR(pos, tr)				\
    do {						\
@@ -535,97 +332,20 @@ void** beam_ops;
      CHECK_TERM(tr);				\
    } while (0)
 
-#define GetArg1(N, Dst) GetR((N), Dst)
-
-#define GetArg2(N, Dst1, Dst2)     \
-   do {                            \
-     GetR(N, Dst1);                \
-     GetR((N)+1, Dst2);            \
-   } while (0)
-
-#define PutList(H, T, Dst)                      \
-  do {                                          \
-   HTOP[0] = (H); HTOP[1] = (T);                \
-   Dst = make_list(HTOP);                       \
-   HTOP += 2;                                   \
-  } while (0)
-
-#define Swap(R1, R2)				\
-  do {						\
-    Eterm V = R1;				\
-    R1 = R2;					\
-    R2 = V;					\
-  } while (0)
-
-#define SwapTemp(R1, R2, Tmp)			\
-  do {						\
-    Eterm V = R1;				\
-    R1 = R2;					\
-    R2 = Tmp = V;				\
-  } while (0)
-
-#define Move(Src, Dst) Dst = (Src)
-
-#define Move2Par(S1, D1, S2, D2)		\
-  do {						\
-      Eterm V1, V2;				\
-      V1 = (S1); V2 = (S2); D1 = V1; D2 = V2;	\
-  } while (0)
-
-#define MoveShift(Src, SD, D)			\
-  do {						\
-    Eterm V;					\
-    V = Src; D = SD; SD = V;			\
-  } while (0)
-
-#define MoveDup(Src, D1, D2)			\
-  do {						\
-    D1 = D2 = (Src);				\
-  } while (0)
-
-#define Move3(S1, D1, S2, D2, S3, D3) D1 = (S1); D2 = (S2); D3 = (S3)
-
-#define MoveWindow3(S1, S2, S3, D)		\
-  do {						\
-      Eterm xt0, xt1, xt2;			\
-      Eterm *y = &D;				\
-      xt0  = S1;				\
-      xt1  = S2;				\
-      xt2  = S3;				\
-      y[0] = xt0;				\
-      y[1] = xt1;				\
-      y[2] = xt2;				\
- } while (0)
-
-#define MoveWindow4(S1, S2, S3, S4, D)		\
-  do {						\
-      Eterm xt0, xt1, xt2, xt3;			\
-      Eterm *y = &D;				\
-      xt0  = S1;				\
-      xt1  = S2;				\
-      xt2  = S3;				\
-      xt3  = S4;				\
-      y[0] = xt0;				\
-      y[1] = xt1;				\
-      y[2] = xt2;				\
-      y[3] = xt3;				\
- } while (0)
-
-#define MoveWindow5(S1, S2, S3, S4, S5, D)	\
-  do {						\
-      Eterm xt0, xt1, xt2, xt3, xt4;		\
-      Eterm *y = &D;				\
-      xt0  = S1;				\
-      xt1  = S2;				\
-      xt2  = S3;				\
-      xt3  = S4;				\
-      xt4  = S5;				\
-      y[0] = xt0;				\
-      y[1] = xt1;				\
-      y[2] = xt2;				\
-      y[3] = xt3;				\
-      y[4] = xt4;				\
- } while (0)
+#define PUT_TERM_REG(term, desc)		\
+do {						\
+    switch (loader_tag(desc)) {			\
+    case LOADER_X_REG:				\
+	x(loader_x_reg_index(desc)) = (term);	\
+	break;					\
+    case LOADER_Y_REG:				\
+	y(loader_y_reg_index(desc)) = (term);	\
+	break;					\
+    default:					\
+	ASSERT(0);				\
+	break;					\
+    }						\
+} while(0)
 
 #define DispatchReturn                          \
 do {                                            \
@@ -640,409 +360,14 @@ do {                                            \
     }						\
 } while (0)
 
-#define MoveReturn(Src)				\
-    x(0) = (Src);				\
-    I = c_p->cp;				\
-    ASSERT(VALID_INSTR(*c_p->cp));		\
-    c_p->cp = 0;				\
-    CHECK_TERM(r(0));				\
-    DispatchReturn
-
-#define DeallocateReturn(Deallocate)       \
-  do {                                     \
-    int words_to_pop = (Deallocate);       \
-    SET_I((BeamInstr *) cp_val(*E));       \
-    E = ADD_BYTE_OFFSET(E, words_to_pop);  \
-    CHECK_TERM(r(0));                      \
-    DispatchReturn;                        \
-  } while (0)
-
-#define MoveDeallocateReturn(Src, Deallocate)	\
-    x(0) = (Src);				\
-    DeallocateReturn(Deallocate)
-
-#define MoveCall(Src, CallDest, Size)		\
-    x(0) = (Src);				\
-    SET_CP(c_p, I+Size+1);			\
-    SET_I((BeamInstr *) CallDest);		\
-    Dispatch();
-
-#define MoveCallLast(Src, CallDest, Deallocate)	\
-    x(0) = (Src);				\
-    RESTORE_CP(E);				\
-    E = ADD_BYTE_OFFSET(E, (Deallocate));	\
-    SET_I((BeamInstr *) CallDest);		\
-    Dispatch();
-
-#define MoveCallOnly(Src, CallDest)		\
-    x(0) = (Src);				\
-    SET_I((BeamInstr *) CallDest);		\
-    Dispatch();
-
-#define MoveJump(Src)				\
-     r(0) = (Src);				\
-     SET_I((BeamInstr *) Arg(0));		\
-     Goto(*I);
-
-#define GetList(Src, H, T)			\
-  do {						\
-    Eterm* tmp_ptr = list_val(Src);		\
-    Eterm hd, tl;				\
-    hd = CAR(tmp_ptr);				\
-    tl = CDR(tmp_ptr);				\
-    H = hd; T = tl;				\
-  } while (0)
-
-#define GetTupleElement(Src, Element, Dest)		\
-  do {							\
-    Eterm* src;						\
-    src = ADD_BYTE_OFFSET(tuple_val(Src), (Element));	\
-    (Dest) = *src;					\
-  } while (0)
-
-#define GetTupleElement2(Src, Element, Dest)		\
-  do {							\
-    Eterm* src;						\
-    Eterm* dst;						\
-    Eterm E1, E2;					\
-    src = ADD_BYTE_OFFSET(tuple_val(Src), (Element));	\
-    dst = &(Dest);					\
-    E1 = src[0];					\
-    E2 = src[1];					\
-    dst[0] = E1;					\
-    dst[1] = E2;					\
-  } while (0)
-
-#define GetTupleElement2Y(Src, Element, D1, D2)		\
-  do {							\
-    Eterm* src;						\
-    Eterm E1, E2;					\
-    src = ADD_BYTE_OFFSET(tuple_val(Src), (Element));	\
-    E1 = src[0];					\
-    E2 = src[1];					\
-    D1 = E1;						\
-    D2 = E2;						\
-  } while (0)
-
-#define GetTupleElement3(Src, Element, Dest)		\
-  do {							\
-    Eterm* src;						\
-    Eterm* dst;						\
-    Eterm E1, E2, E3;					\
-    src = ADD_BYTE_OFFSET(tuple_val(Src), (Element));	\
-    dst = &(Dest);					\
-    E1 = src[0];					\
-    E2 = src[1];					\
-    E3 = src[2];					\
-    dst[0] = E1;					\
-    dst[1] = E2;					\
-    dst[2] = E3;					\
-  } while (0)
-
-#define EqualImmed(X, Y, Action) if (X != Y) { Action; }
-#define NotEqualImmed(X, Y, Action) if (X == Y) { Action; }
-#define EqualExact(X, Y, Action) if (!EQ(X,Y)) { Action; }
-#define NotEqualExact(X, Y, Action) if (EQ(X,Y)) { Action; }
-#define Equal(X, Y, Action) CMP_EQ_ACTION(X,Y,Action)
-#define NotEqual(X, Y, Action) CMP_NE_ACTION(X,Y,Action)
-#define IsLessThan(X, Y, Action) CMP_LT_ACTION(X,Y,Action)
-#define IsGreaterEqual(X, Y, Action) CMP_GE_ACTION(X,Y,Action)
-
-#define IsFloat(Src, Fail) if (is_not_float(Src)) { Fail; }
-
-#define IsInteger(Src, Fail) if (is_not_integer(Src)) { Fail; }
-
-#define IsNumber(X, Fail) if (is_not_integer(X) && is_not_float(X)) { Fail; }
-
-#define IsAtom(Src, Fail) if (is_not_atom(Src)) { Fail; }
-
-#define IsIntegerAllocate(Src, Need, Alive, Fail)  \
-    if (is_not_integer(Src)) { Fail; }             \
-    A(Need, Alive)
-
-#define IsNil(Src, Fail) if (is_not_nil(Src)) { Fail; }
-
-#define IsList(Src, Fail) if (is_not_list(Src) && is_not_nil(Src)) { Fail; }
-
-#define IsNonemptyList(Src, Fail) if (is_not_list(Src)) { Fail; }
-
-#define IsNonemptyListAllocate(Src, Need, Alive, Fail)  \
-    if (is_not_list(Src)) { Fail; }                     \
-    A(Need, Alive)
-
-#define IsNonemptyListTestHeap(Need, Alive, Fail)  \
-    if (is_not_list(x(0))) { Fail; }			\
-    TestHeap(Need, Alive)
-
-#define IsNonemptyListGetList(Src, H, T, Fail)	\
-    if (is_not_list(Src)) {			\
-         Fail;					\
-    } else {					\
-       Eterm* tmp_ptr = list_val(Src);		\
-       Eterm hd, tl;				\
-       hd = CAR(tmp_ptr);			\
-       tl = CDR(tmp_ptr);			\
-       H = hd; T = tl;				\
-    }
-
-#define IsTuple(X, Action) if (is_not_tuple(X)) Action
-
-#define IsArity(Pointer, Arity, Fail)		\
-    if (*tuple_val(Pointer) != (Arity)) {	\
-        Fail;					\
-    }
-
-#define IsMap(Src, Fail) if (!is_map(Src)) { Fail; }
-
-#define GetMapElement(Src, Key, Dst, Fail)	\
-  do {						\
-     Eterm _res = get_map_element(Src, Key);	\
-     if (is_non_value(_res)) {			\
-        Fail;					\
-     }						\
-     Dst = _res;				\
-  } while (0)
-
-#define GetMapElementHash(Src, Key, Hx, Dst, Fail)	\
-  do {							\
-     Eterm _res = get_map_element_hash(Src, Key, Hx);	\
-     if (is_non_value(_res)) {				\
-        Fail;						\
-     }							\
-     Dst = _res;					\
-  } while (0)
-
-#define IsFunction(X, Action)			\
-  do {						\
-     if ( !(is_any_fun(X)) ) {			\
-          Action;				\
-     }						\
-  } while (0)
-
-#define IsFunction2(F, A, Action)			\
-  do {							\
-     if (erl_is_function(c_p, F, A) != am_true ) {	\
-          Action;					\
-     }							\
-  } while (0)
-
 #ifdef DEBUG
-#define IsTupleOfArity(Src, Arityval, Fail)			\
-  do {								\
-    if (!(is_tuple(Src) && *tuple_val(Src) == Arityval)) {	\
-        Fail;							\
-    }								\
-  } while (0)
-#else
-#define IsTupleOfArity(Src, Arityval, Fail)			\
-  do {								\
-    if (!(is_boxed(Src) && *tuple_val(Src) == Arityval)) {	\
-        Fail;							\
-    }								\
-  } while (0)
-#endif
-
-#define IsTaggedTuple(Src,Arityval,Tag,Fail) \
-  do {                                       \
-    if (!(is_tuple(Src) &&                   \
-         (tuple_val(Src))[0] == Arityval &&  \
-         (tuple_val(Src))[1] == Tag)) {      \
-        Fail;                                \
-    }                                        \
-  } while (0)
-
-#define IsBoolean(X, Fail) if ((X) != am_true && (X) != am_false) { Fail; }
-
-#define IsBinary(Src, Fail) \
- if (is_not_binary(Src) || binary_bitsize(Src) != 0) { Fail; }
-
-#define IsBitstring(Src, Fail) \
-  if (is_not_binary(Src)) { Fail; }
-
-#if defined(ARCH_64)
-#define BsSafeMul(A, B, Fail, Target)		\
-   do { Uint64 _res = (A) * (B);		\
-      if (_res / B != A) { Fail; }		\
-      Target = _res;				\
-   } while (0)
+/* Better static type testing by the C compiler */
+#  define BEAM_IS_TUPLE(Src) is_tuple(Src)
 #else
-#define BsSafeMul(A, B, Fail, Target)			\
-   do { Uint64 _res = (Uint64)(A) * (Uint64)(B);	\
-      if ((_res >> (8*sizeof(Uint))) != 0) { Fail; }	\
-      Target = _res;					\
-   } while (0)
+/* Better performance */
+# define BEAM_IS_TUPLE(Src) is_boxed(Src)
 #endif
 
-#define BsGetFieldSize(Bits, Unit, Fail, Target)	\
-   do {							\
-      Sint _signed_size; Uint _uint_size;		\
-      Uint temp_bits;					\
-      if (is_small(Bits)) {				\
-        _signed_size = signed_val(Bits);		\
-         if (_signed_size < 0) { Fail; }		\
-         _uint_size = (Uint) _signed_size;		\
-      } else {						\
-         if (!term_to_Uint(Bits, &temp_bits)) { Fail; }	\
-         _uint_size = temp_bits;			\
-      }							\
-      BsSafeMul(_uint_size, Unit, Fail, Target);	\
-   } while (0)
-
-#define BsGetUncheckedFieldSize(Bits, Unit, Fail, Target)	\
-   do {								\
-      Sint _signed_size; Uint _uint_size;			\
-      Uint temp_bits;						\
-      if (is_small(Bits)) {					\
-        _signed_size = signed_val(Bits);			\
-         if (_signed_size < 0) { Fail; }			\
-         _uint_size = (Uint) _signed_size;			\
-      } else {							\
-         if (!term_to_Uint(Bits, &temp_bits)) { Fail; }		\
-         _uint_size = (Uint) temp_bits;				\
-      }								\
-      Target = _uint_size * Unit;				\
-   } while (0)
-
-#define BsGetFloat2(Ms, Live, Sz, Flags, Dst, Fail)                     \
- do {									\
-   ErlBinMatchBuffer *_mb;						\
-   Eterm _result; Sint _size;						\
-   if (!is_small(Sz) || (_size = unsigned_val(Sz)) > 64) { Fail; }	\
-   _size *= ((Flags) >> 3);						\
-   TestHeap(FLOAT_SIZE_OBJECT, Live);					\
-   _mb = ms_matchbuffer(Ms);						\
-   LIGHT_SWAPOUT;							\
-   _result = erts_bs_get_float_2(c_p, _size, (Flags), _mb);		\
-   LIGHT_SWAPIN;							\
-   HEAP_SPACE_VERIFIED(0);                                              \
-   if (is_non_value(_result)) { Fail; }					\
-   else { Dst = _result; }                                              \
- } while (0)
-
-#define BsGetBinaryImm_2(Ms, Live, Sz, Flags, Dst, Fail)	\
-  do {								\
-    ErlBinMatchBuffer *_mb;					\
-    Eterm _result;						\
-    TestHeap(heap_bin_size(ERL_ONHEAP_BIN_LIMIT), Live);	\
-    _mb = ms_matchbuffer(Ms);					\
-    LIGHT_SWAPOUT;						\
-    _result = erts_bs_get_binary_2(c_p, (Sz), (Flags), _mb);	\
-    LIGHT_SWAPIN;						\
-    HEAP_SPACE_VERIFIED(0);                                     \
-    if (is_non_value(_result)) { Fail; }			\
-    else { Dst = _result; }                                     \
-  } while (0)
-
-#define BsGetBinary_2(Ms, Live, Sz, Flags, Dst, Fail)           \
-  do {								\
-    ErlBinMatchBuffer *_mb;					\
-    Eterm _result; Uint _size;					\
-    BsGetFieldSize(Sz, ((Flags) >> 3), Fail, _size);		\
-    TestHeap(ERL_SUB_BIN_SIZE, Live);				\
-    _mb = ms_matchbuffer(Ms);					\
-    LIGHT_SWAPOUT;						\
-    _result = erts_bs_get_binary_2(c_p, _size, (Flags), _mb);	\
-    LIGHT_SWAPIN;						\
-    HEAP_SPACE_VERIFIED(0);                                     \
-    if (is_non_value(_result)) { Fail; }			\
-    else { Dst = _result; }                                     \
-  } while (0)
-
-#define BsGetBinaryAll_2(Ms, Live, Unit, Dst, Fail)	\
-  do {                                                  \
-    ErlBinMatchBuffer *_mb;                             \
-    Eterm _result;                                      \
-    TestHeap(ERL_SUB_BIN_SIZE, Live);                   \
-    _mb = ms_matchbuffer(Ms);                           \
-    if (((_mb->size - _mb->offset) % Unit) == 0) {      \
-      LIGHT_SWAPOUT;                                    \
-      _result = erts_bs_get_binary_all_2(c_p, _mb);     \
-      LIGHT_SWAPIN;                                     \
-      HEAP_SPACE_VERIFIED(0);                           \
-      ASSERT(is_value(_result));                        \
-      Dst = _result;					\
-    } else {                                            \
-	HEAP_SPACE_VERIFIED(0);                         \
-	Fail; }                                         \
- } while (0)
-
-#define BsSkipBits2(Ms, Bits, Unit, Fail)			\
- do {								\
-   ErlBinMatchBuffer *_mb;					\
-   size_t new_offset;						\
-   Uint _size;							\
-    _mb = ms_matchbuffer(Ms);					\
-   BsGetFieldSize(Bits, Unit, Fail, _size);			\
-   new_offset = _mb->offset + _size;				\
-   if (new_offset <= _mb->size) { _mb->offset = new_offset; }	\
-   else { Fail; }						\
- } while (0)
-
-#define BsSkipBitsAll2(Ms, Unit, Fail)		\
- do {						\
-    ErlBinMatchBuffer *_mb;			\
-   _mb = ms_matchbuffer(Ms);			\
-   if (((_mb->size - _mb->offset) % Unit) == 0) {_mb->offset = _mb->size; } \
-   else { Fail; }					\
- } while (0)
-
-#define BsSkipBitsImm2(Ms, Bits, Fail)				\
- do {								\
-   ErlBinMatchBuffer *_mb;					\
-   size_t new_offset;						\
-   _mb = ms_matchbuffer(Ms);					\
-   new_offset = _mb->offset + (Bits);				\
-   if (new_offset <= _mb->size) { _mb->offset = new_offset; }	\
-   else { Fail; }						\
- } while (0)
-
-#define NewBsPutIntegerImm(Sz, Flags, Src)					\
- do {									\
-    if (!erts_new_bs_put_integer(ERL_BITS_ARGS_3((Src), (Sz), (Flags)))) { goto badarg; }	\
- } while (0)
-
-#define NewBsPutInteger(Sz, Flags, Src)						\
- do {										\
-    Sint _size;									\
-    BsGetUncheckedFieldSize(Sz, ((Flags) >> 3), goto badarg, _size);		\
-    if (!erts_new_bs_put_integer(ERL_BITS_ARGS_3((Src), _size, (Flags))))	\
-       { goto badarg; }								\
- } while (0)
-
-#define NewBsPutFloatImm(Sz, Flags, Src)					\
- do {									\
-    if (!erts_new_bs_put_float(c_p, (Src), (Sz), (Flags))) { goto badarg; }	\
- } while (0)
-
-#define NewBsPutFloat(Sz, Flags, Src)						\
- do {										\
-    Sint _size;									\
-    BsGetUncheckedFieldSize(Sz, ((Flags) >> 3), goto badarg, _size);		\
-    if (!erts_new_bs_put_float(c_p, (Src), _size, (Flags))) { goto badarg; }	\
- } while (0)
-
-#define NewBsPutBinary(Sz, Flags, Src)							\
- do {											\
-    Sint _size;										\
-    BsGetUncheckedFieldSize(Sz, ((Flags) >> 3), goto badarg, _size);			\
-    if (!erts_new_bs_put_binary(ERL_BITS_ARGS_2((Src), _size))) { goto badarg; }	\
- } while (0)
-
-#define NewBsPutBinaryImm(Sz, Src)				        \
- do {							        \
-    if (!erts_new_bs_put_binary(ERL_BITS_ARGS_2((Src), (Sz)))) { goto badarg; }	\
- } while (0)
-
-#define NewBsPutBinaryAll(Src, Unit)							\
- do {											\
-    if (!erts_new_bs_put_binary_all(ERL_BITS_ARGS_2((Src), (Unit)))) { goto badarg; }	\
- } while (0)
-
-
-#define IsPort(Src, Fail) if (is_not_port(Src)) { Fail; }
-#define IsPid(Src, Fail) if (is_not_pid(Src)) { Fail; }
-#define IsRef(Src, Fail) if (is_not_ref(Src)) { Fail; }
-
 /*
  * process_main() is already huge, so we want to avoid inlining
  * into it. Especially functions that are seldom used.
@@ -1058,6 +383,7 @@ do {                                            \
  * The following functions are called directly by process_main().
  * Don't inline them.
  */
+static void init_emulator_finish(void) NOINLINE;
 static ErtsCodeMFA *ubif2mfa(void* uf) NOINLINE;
 static ErtsCodeMFA *gcbif2mfa(void* gcf) NOINLINE;
 static BeamInstr* handle_error(Process* c_p, BeamInstr* pc,
@@ -1066,20 +392,22 @@ static BeamInstr* call_error_handler(Process* p, ErtsCodeMFA* mfa,
 				     Eterm* reg, Eterm func) NOINLINE;
 static BeamInstr* fixed_apply(Process* p, Eterm* reg, Uint arity,
 			      BeamInstr *I, Uint offs) NOINLINE;
-static BeamInstr* apply(Process* p, Eterm module, Eterm function,
-			Eterm args, Eterm* reg,
-			BeamInstr *I, Uint offs) NOINLINE;
+static BeamInstr* apply(Process* p, Eterm* reg,
+                        BeamInstr *I, Uint offs) NOINLINE;
 static BeamInstr* call_fun(Process* p, int arity,
 			   Eterm* reg, Eterm args) NOINLINE;
 static BeamInstr* apply_fun(Process* p, Eterm fun,
 			    Eterm args, Eterm* reg) NOINLINE;
 static Eterm new_fun(Process* p, Eterm* reg,
 		     ErlFunEntry* fe, int num_free) NOINLINE;
-static Eterm new_map(Process* p, Eterm* reg, BeamInstr* I) NOINLINE;
-static Eterm update_map_assoc(Process* p, Eterm* reg,
-			      Eterm map, BeamInstr* I) NOINLINE;
-static Eterm update_map_exact(Process* p, Eterm* reg,
-			      Eterm map, BeamInstr* I) NOINLINE;
+static Eterm erts_gc_new_map(Process* p, Eterm* reg, Uint live,
+                             Uint n, BeamInstr* ptr) NOINLINE;
+static Eterm erts_gc_new_small_map_lit(Process* p, Eterm* reg, Eterm keys_literal,
+                               Uint live, BeamInstr* ptr) NOINLINE;
+static Eterm erts_gc_update_map_assoc(Process* p, Eterm* reg, Uint live,
+                              Uint n, BeamInstr* new_p) NOINLINE;
+static Eterm erts_gc_update_map_exact(Process* p, Eterm* reg, Uint live,
+                              Uint n, Eterm* new_p) NOINLINE;
 static Eterm get_map_element(Eterm map, Eterm key);
 static Eterm get_map_element_hash(Eterm map, Eterm key, Uint32 hx);
 
@@ -1111,6 +439,12 @@ init_emulator(void)
 #  define REG_stop asm("%l3")
 #  define REG_I asm("%l4")
 #  define REG_fcalls asm("%l5")
+#elif defined(__GNUC__) && defined(__amd64__) && !defined(DEBUG)
+#  define REG_xregs asm("%r12")
+#  define REG_htop
+#  define REG_stop asm("%r13")
+#  define REG_I asm("%rbx")
+#  define REG_fcalls asm("%r14")
 #else
 #  define REG_xregs
 #  define REG_htop
@@ -1230,6 +564,13 @@ init_emulator(void)
 #define ERTS_DBG_CHK_REDS(P, FC)
 #endif
 
+#ifdef NO_FPE_SIGNALS
+#  define ERTS_NO_FPE_CHECK_INIT ERTS_FP_CHECK_INIT
+#  define ERTS_NO_FPE_ERROR ERTS_FP_ERROR
+#else
+#  define ERTS_NO_FPE_CHECK_INIT(p)
+#  define ERTS_NO_FPE_ERROR(p, a, b)
+#endif
 
 /*
  * process_main() is called twice:
@@ -1289,12 +630,10 @@ void process_main(Eterm * x_reg_array, FloatDef* f_reg_array)
 #ifndef NO_JUMP_TABLE
     static void* opcodes[] = { DEFINE_OPCODES };
 #else
-    int Go;
+    register BeamInstr Go;
 #endif
 #endif
 
-    Eterm pt_arity;		/* Used by do_put_tuple */
-
     Uint64 start_time = 0;          /* Monitor long schedule */
     BeamInstr* start_time_i = NULL;
 
@@ -1311,7 +650,7 @@ void process_main(Eterm * x_reg_array, FloatDef* f_reg_array)
      * Note: c_p->arity must be set to reflect the number of useful terms in
      * c_p->arg_reg before calling the scheduler.
      */
-    if (!init_done) {
+    if (ERTS_UNLIKELY(!init_done)) {
        /* This should only be reached during the init phase when only the main
         * process is running. I.e. there is no race for init_done.
         */
@@ -1344,16 +683,16 @@ void process_main(Eterm * x_reg_array, FloatDef* f_reg_array)
     }
 
     PROCESS_MAIN_CHK_LOCKS(c_p);
-    ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
+    ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
     ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
     c_p = erts_schedule(NULL, c_p, reds_used);
     ASSERT(!(c_p->flags & F_HIPE_MODE));
     ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
     start_time = 0;
 #ifdef DEBUG
-    pid = c_p->common.id; /* Save for debugging purpouses */
+    pid = c_p->common.id; /* Save for debugging purposes */
 #endif
-    ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
+    ERTS_REQ_PROC_MAIN_LOCK(c_p);
     PROCESS_MAIN_CHK_LOCKS(c_p);
 
     ERTS_MSACC_UPDATE_CACHE_X();
@@ -1367,7 +706,7 @@ void process_main(Eterm * x_reg_array, FloatDef* f_reg_array)
     {
 	int reds;
 	Eterm* argp;
-	BeamInstr *next;
+	BeamInstr next;
 	int i;
 
 	argp = c_p->arg_reg;
@@ -1399,7 +738,7 @@ void process_main(Eterm * x_reg_array, FloatDef* f_reg_array)
 
 	ERTS_DBG_CHK_REDS(c_p, FCALLS);
 
-	next = (BeamInstr *) *I;
+	next = *I;
 	SWAPIN;
 	ASSERT(VALID_INSTR(next));
 
@@ -1435,1923 +774,8 @@ void process_main(Eterm * x_reg_array, FloatDef* f_reg_array)
 #ifdef NO_JUMP_TABLE
     switch (Go) {
 #endif
-#include "beam_hot.h"
-
-	{
-	    Eterm increment_reg_val;
-	    Eterm increment_val;
-	    Uint live;
-	    Eterm result;
-
-	OpCase(i_increment_rIId):
-	    increment_reg_val = x(0);
-	    I--;
-	    goto do_increment;
-
-	OpCase(i_increment_xIId):
-	    increment_reg_val = xb(Arg(0));
-	    goto do_increment;
-
-	OpCase(i_increment_yIId):
-	    increment_reg_val = yb(Arg(0));
-	    goto do_increment;
-
-	do_increment:
-	    increment_val = Arg(1);
-	    if (is_small(increment_reg_val)) {
-		Sint i = signed_val(increment_reg_val) + increment_val;
-		ASSERT(MY_IS_SSMALL(i) == IS_SSMALL(i));
-		if (MY_IS_SSMALL(i)) {
-		    result = make_small(i);
-		    StoreBifResult(3, result);
-		}
-	    }
-
-	    live = Arg(2);
-	    HEAVY_SWAPOUT;
-	    reg[live] = increment_reg_val;
-	    reg[live+1] = make_small(increment_val);
-	    result = erts_gc_mixed_plus(c_p, reg, live);
-	    HEAVY_SWAPIN;
-	    ERTS_HOLE_CHECK(c_p);
-	    if (is_value(result)) {
-		StoreBifResult(3, result);
-	    }
-	    ASSERT(c_p->freason != BADMATCH || is_value(c_p->fvalue));
-	    goto find_func_info;
-	}
-
-#define DO_OUTLINED_ARITH_2(name, Op1, Op2)	\
- do {						\
-     Eterm result;				\
-     Uint live = Arg(1);			\
-						\
-     HEAVY_SWAPOUT;				\
-     reg[live] = Op1;				\
-     reg[live+1] = Op2;				\
-     result = erts_gc_##name(c_p, reg, live);	\
-     HEAVY_SWAPIN;				\
-     ERTS_HOLE_CHECK(c_p);			\
-     if (is_value(result)) {			\
-	 StoreBifResult(4, result);		\
-     }						\
-     goto lb_Cl_error;				\
- } while (0)
-
- {
-     Eterm PlusOp1, PlusOp2;
-     Eterm result;
-
- OpCase(i_plus_jIxxd):
-     PlusOp1 = xb(Arg(2));
-     PlusOp2 = xb(Arg(3));
-     goto do_plus;
-
- OpCase(i_plus_jIxyd):
-     PlusOp1 = xb(Arg(2));
-     PlusOp2 = yb(Arg(3));
-     goto do_plus;
-
- OpCase(i_plus_jIssd):
-     GetArg2(2, PlusOp1, PlusOp2);
-     goto do_plus;
-
- do_plus:
-     if (is_both_small(PlusOp1, PlusOp2)) {
-	 Sint i = signed_val(PlusOp1) + signed_val(PlusOp2);
-	 ASSERT(MY_IS_SSMALL(i) == IS_SSMALL(i));
-	 if (MY_IS_SSMALL(i)) {
-	     result = make_small(i);
-             StoreBifResult(4, result);
-	 }
-     }
-     DO_OUTLINED_ARITH_2(mixed_plus, PlusOp1, PlusOp2);
- }
-
- {
-     Eterm MinusOp1, MinusOp2;
-     Eterm result;
-
- OpCase(i_minus_jIxxd):
-     MinusOp1 = xb(Arg(2));
-     MinusOp2 = xb(Arg(3));
-     goto do_minus;
-
- OpCase(i_minus_jIssd):
-     GetArg2(2, MinusOp1, MinusOp2);
-     goto do_minus;
-
- do_minus:
-     if (is_both_small(MinusOp1, MinusOp2)) {
-	 Sint i = signed_val(MinusOp1) - signed_val(MinusOp2);
-	 ASSERT(MY_IS_SSMALL(i) == IS_SSMALL(i));
-	 if (MY_IS_SSMALL(i)) {
-	     result = make_small(i);
-             StoreBifResult(4, result);
-	 }
-     }
-     DO_OUTLINED_ARITH_2(mixed_minus, MinusOp1, MinusOp2);
- }
-
-    {
-	Eterm is_eq_exact_lit_val;
-
-    OpCase(i_is_eq_exact_literal_fxc):
-	is_eq_exact_lit_val = xb(Arg(1));
-	goto do_is_eq_exact_literal;
-
-    OpCase(i_is_eq_exact_literal_fyc):
-	is_eq_exact_lit_val = yb(Arg(1));
-	goto do_is_eq_exact_literal;
-
-    do_is_eq_exact_literal:
-	if (!eq(Arg(2), is_eq_exact_lit_val)) {
-	    ClauseFail();
-	}
-	Next(3);
-    }
-
-    {
-	Eterm is_ne_exact_lit_val;
-
-    OpCase(i_is_ne_exact_literal_fxc):
-	is_ne_exact_lit_val = xb(Arg(1));
-	goto do_is_ne_exact_literal;
-
-    OpCase(i_is_ne_exact_literal_fyc):
-	is_ne_exact_lit_val = yb(Arg(1));
-	goto do_is_ne_exact_literal;
-
-    do_is_ne_exact_literal:
-	if (eq(Arg(2), is_ne_exact_lit_val)) {
-	    ClauseFail();
-	}
-	Next(3);
-    }
-
- OpCase(i_move_call_only_fc): {
-     r(0) = Arg(1);
- }
- /* FALL THROUGH */
- OpCase(i_call_only_f): {
-     SET_I((BeamInstr *) Arg(0));
-     DTRACE_LOCAL_CALL(c_p, erts_code_to_codemfa(I));
-     Dispatch();
- }
-
- OpCase(i_move_call_last_fPc): {
-     r(0) = Arg(2);
- }
- /* FALL THROUGH */
- OpCase(i_call_last_fP): {
-     RESTORE_CP(E);
-     E = ADD_BYTE_OFFSET(E, Arg(1));
-     SET_I((BeamInstr *) Arg(0));
-     DTRACE_LOCAL_CALL(c_p, erts_code_to_codemfa(I));
-     Dispatch();
- }
-
- OpCase(i_move_call_cf): {
-     r(0) = Arg(0);
-     I++;
- }
- /* FALL THROUGH */
- OpCase(i_call_f): {
-     SET_CP(c_p, I+2);
-     SET_I((BeamInstr *) Arg(0));
-     DTRACE_LOCAL_CALL(c_p, erts_code_to_codemfa(I));
-     Dispatch();
- }
-
- OpCase(i_move_call_ext_last_ePc): {
-     r(0) = Arg(2);
- }
- /* FALL THROUGH */
- OpCase(i_call_ext_last_eP):
-    RESTORE_CP(E);
-    E = ADD_BYTE_OFFSET(E, Arg(1));
-
-    /*
-     * Note: The pointer to the export entry is never NULL; if the module
-     * is not loaded, it points to code which will invoke the error handler
-     * (see lb_call_error_handler below).
-     */
-    DTRACE_GLOBAL_CALL_FROM_EXPORT(c_p, Arg(0));
-    Dispatchx();
-
- OpCase(i_move_call_ext_ce): {
-     r(0) = Arg(0);
-     I++;
- }
- /* FALL THROUGH */
- OpCase(i_call_ext_e):
-    SET_CP(c_p, I+2);
-    DTRACE_GLOBAL_CALL_FROM_EXPORT(c_p, Arg(0));
-    Dispatchx();
-
- OpCase(i_move_call_ext_only_ec): {
-     r(0) = Arg(1);
- }
- /* FALL THROUGH */
- OpCase(i_call_ext_only_e):
-    DTRACE_GLOBAL_CALL_FROM_EXPORT(c_p, Arg(0));
-    Dispatchx();
-
- OpCase(init_y): {
-     BeamInstr *next;
-
-     PreFetch(1, next);
-     make_blank(yb(Arg(0)));
-     NextPF(1, next);
- }
-
- OpCase(i_trim_I): {
-     BeamInstr *next;
-     Uint words;
-     Uint cp;
-
-     words = Arg(0);
-     cp = E[0];
-     PreFetch(1, next);
-     E += words;
-     E[0] = cp;
-     NextPF(1, next);
- }
-
- OpCase(move_x1_c): {
-	x(1) = Arg(0);
-	Next(1);
-    }
-
- OpCase(move_x2_c): {
-	x(2) = Arg(0);
-	Next(1);
-    }
-
- OpCase(return): {
-    SET_I(c_p->cp);
-    DTRACE_RETURN_FROM_PC(c_p);
-    /*
-     * We must clear the CP to make sure that a stale value do not
-     * create a false module dependcy preventing code upgrading.
-     * It also means that we can use the CP in stack backtraces.
-     */
-    c_p->cp = 0;
-    CHECK_TERM(r(0));
-    HEAP_SPACE_VERIFIED(0);
-    DispatchReturn;
- }
-
-    /*
-     * Send is almost a standard call-BIF with two arguments, except for:
-     *    1) It cannot be traced.
-     *	  2) There is no pointer to the send_2 function stored in
-     *       the instruction.
-     */
-
- OpCase(send): {
-     BeamInstr *next;
-     Eterm result;
-
-     if (!(FCALLS > 0 || FCALLS > neg_o_reds)) {
-         /* If we have run out of reductions, we do a context
-            switch before calling the bif */
-         c_p->arity = 2;
-         c_p->current = NULL;
-         goto context_switch3;
-     }
-
-     PRE_BIF_SWAPOUT(c_p);
-     c_p->fcalls = FCALLS - 1;
-     result = erl_send(c_p, r(0), x(1));
-     PreFetch(0, next);
-     ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-     ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
-     PROCESS_MAIN_CHK_LOCKS(c_p);
-     HTOP = HEAP_TOP(c_p);
-     FCALLS = c_p->fcalls;
-     if (is_value(result)) {
-	 r(0) = result;
-	 CHECK_TERM(r(0));
-	 NextPF(0, next);
-     } else if (c_p->freason == TRAP) {
-	 SET_CP(c_p, I+1);
-	 SET_I(c_p->i);
-	 SWAPIN;
-	 Dispatch();
-     }
-     goto find_func_info;
- }
-
-    {
-	Eterm element_index;
-	Eterm element_tuple;
-
-    OpCase(i_element_jxsd):
-	element_tuple = xb(Arg(1));
-	goto do_element;
-
-    OpCase(i_element_jysd):
-	element_tuple = yb(Arg(1));
-	goto do_element;
-
-    do_element:
-	GetArg1(2, element_index);
-	if (is_small(element_index) && is_tuple(element_tuple)) {
-	    Eterm* tp = tuple_val(element_tuple);
-
-	    if ((signed_val(element_index) >= 1) &&
-		(signed_val(element_index) <= arityval(*tp))) {
-		Eterm result = tp[signed_val(element_index)];
-		StoreBifResult(3, result);
-	    }
-	}
-    }
- /* Fall through */
-
- OpCase(badarg_j):
- badarg:
-    c_p->freason = BADARG;
-    goto lb_Cl_error;
-
-    {
-	Eterm fast_element_tuple;
-
-    OpCase(i_fast_element_jxId):
-     fast_element_tuple = xb(Arg(1));
-     goto do_fast_element;
-
-    OpCase(i_fast_element_jyId):
-     fast_element_tuple = yb(Arg(1));
-     goto do_fast_element;
-
-    do_fast_element:
-	if (is_tuple(fast_element_tuple)) {
-	    Eterm* tp = tuple_val(fast_element_tuple);
-	    Eterm pos = Arg(2);	/* Untagged integer >= 1 */
-	    if (pos <= arityval(*tp)) {
-		Eterm result = tp[pos];
-		StoreBifResult(3, result);
-	    }
-	}
-     goto badarg;
- }
-
- OpCase(catch_yf):
-     c_p->catches++;
-     yb(Arg(0)) = Arg(1);
-     Next(2);
-
- OpCase(catch_end_y): {
-     c_p->catches--;
-     make_blank(yb(Arg(0)));
-     if (is_non_value(r(0))) {
-         c_p->fvalue = NIL;
-	 if (x(1) == am_throw) {
-	     r(0) = x(2);
-	 } else {
-	     if (x(1) == am_error) {
-	         SWAPOUT;
-		 x(2) = add_stacktrace(c_p, x(2), x(3));
-		 SWAPIN;
-	     }
-	     /* only x(2) is included in the rootset here */
-	     if (E - HTOP < 3) {
-		 SWAPOUT;
-		 PROCESS_MAIN_CHK_LOCKS(c_p);
-		 FCALLS -= erts_garbage_collect_nobump(c_p, 3, reg+2, 1, FCALLS);
-		 ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-		 PROCESS_MAIN_CHK_LOCKS(c_p);
-		 SWAPIN;
-	     }
-	     r(0) = TUPLE2(HTOP, am_EXIT, x(2));
-	     HTOP += 3;
-	 }
-     }
-     CHECK_TERM(r(0));
-     Next(1);
- }
-
- OpCase(try_end_y): {
-     c_p->catches--;
-     make_blank(yb(Arg(0)));
-     if (is_non_value(r(0))) {
-         c_p->fvalue = NIL;
-	 r(0) = x(1);
-	 x(1) = x(2);
-	 x(2) = x(3);
-     }
-     Next(1);
- }
-
- /*
-  * Skeleton for receive statement:
-  *
-  *             recv_mark L1                     Optional
-  *             call make_ref/monitor            Optional
-  *             ...
-  *             recv_set L1                      Optional
-  *      L1:          <-------------------+
-  *                   <-----------+       |
-  *     	     	       	  |   	  |
-  *             loop_rec L2 ------+---+   |
-  *             ...               |   |   |
-  *             remove_message 	  |   |	  |
-  *             jump L3           |   |   |
-  *		...	          |   |   |
-  *		loop_rec_end L1 --+   |   |
-  *      L2:          <---------------+   |
-  *	   	wait L1  -----------------+      or wait_timeout
-  *		timeout
-  *
-  *	 L3:    Code after receive...
-  *
-  *
-  */
-
- OpCase(recv_mark_f): {
-     /*
-      * Save the current position in message buffer and the
-      * the label for the loop_rec/2 instruction for the
-      * the receive statement.
-      */
-     c_p->msg.mark = (BeamInstr *) Arg(0);
-     c_p->msg.saved_last = c_p->msg.last;
-     Next(1);
- }
-
- OpCase(i_recv_set): {
-     /*
-      * If the mark is valid (points to the loop_rec/2
-      * instruction that follows), we know that the saved
-      * position points to the first message that could
-      * possibly be matched out.
-      *
-      * If the mark is invalid, we do nothing, meaning that
-      * we will look through all messages in the message queue.
-      */
-     if (c_p->msg.mark == (BeamInstr *) (I+1)) {
-	 c_p->msg.save = c_p->msg.saved_last;
-     }
-     I++;
-     /* Fall through to the loop_rec/2 instruction */
- }
-
-    /*
-     * Pick up the next message and place it in x(0).
-     * If no message, jump to a wait or wait_timeout instruction.
-     */
- OpCase(i_loop_rec_f):
- {
-     BeamInstr *next;
-     ErtsMessage* msgp;
-
-     /*
-      * We need to disable GC while matching messages
-      * in the queue. This since messages with data outside
-      * the heap will be corrupted by a GC.
-      */
-     ASSERT(!(c_p->flags & F_DELAY_GC));
-     c_p->flags |= F_DELAY_GC;
-
- loop_rec__:
-
-     PROCESS_MAIN_CHK_LOCKS(c_p);
-
-     msgp = PEEK_MESSAGE(c_p);
-
-     if (!msgp) {
-#ifdef ERTS_SMP
-	 erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
-	 /* Make sure messages wont pass exit signals... */
-	 if (ERTS_PROC_PENDING_EXIT(c_p)) {
-	     erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
-	     SWAPOUT;
-	     c_p->flags &= ~F_DELAY_GC;
-             c_p->arity = 0;
-	     goto do_schedule; /* Will be rescheduled for exit */
-	 }
-	 ERTS_SMP_MSGQ_MV_INQ2PRIVQ(c_p);
-	 msgp = PEEK_MESSAGE(c_p);
-	 if (msgp)
-	     erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
-	 else
-#endif
-	 {
-	     c_p->flags &= ~F_DELAY_GC;
-	     SET_I((BeamInstr *) Arg(0));
-	     Goto(*I);		/* Jump to a wait or wait_timeout instruction */
-	 }
-     }
-     if (is_non_value(ERL_MESSAGE_TERM(msgp))) {
-	 SWAPOUT; /* erts_decode_dist_message() may write to heap... */
-	 if (!erts_decode_dist_message(c_p, ERTS_PROC_LOCK_MAIN, msgp, 0)) {
-	     /*
-	      * A corrupt distribution message that we weren't able to decode;
-	      * remove it...
-	      */
-	     /* No swapin should be needed */
-	     ASSERT(HTOP == c_p->htop && E == c_p->stop);
-	     /* TODO: Add DTrace probe for this bad message situation? */
-	     UNLINK_MESSAGE(c_p, msgp);
-	     msgp->next = NULL;
-	     erts_cleanup_messages(msgp);
-	     goto loop_rec__;
-	 }
-	 SWAPIN;
-     }
-     PreFetch(1, next);
-     r(0) = ERL_MESSAGE_TERM(msgp);
-     NextPF(1, next);
- }
-
- /*
-  * Remove a (matched) message from the message queue.
-  */
- OpCase(remove_message): {
-     BeamInstr *next;
-     ErtsMessage* msgp;
-     PROCESS_MAIN_CHK_LOCKS(c_p);
-
-     ERTS_CHK_MBUF_SZ(c_p);
-
-     PreFetch(0, next);
-     msgp = PEEK_MESSAGE(c_p);
-
-     if (ERTS_PROC_GET_SAVED_CALLS_BUF(c_p)) {
-	 save_calls(c_p, &exp_receive);
-     }
-     if (ERL_MESSAGE_TOKEN(msgp) == NIL) {
-#ifdef USE_VM_PROBES
-	 if (DT_UTAG(c_p) != NIL) {
-	     if (DT_UTAG_FLAGS(c_p) & DT_UTAG_PERMANENT) {
-		 SEQ_TRACE_TOKEN(c_p) = am_have_dt_utag;
-	     } else {
-		 DT_UTAG(c_p) = NIL;
-		 SEQ_TRACE_TOKEN(c_p) = NIL;
-	     }
-	 } else {
-#endif
-	     SEQ_TRACE_TOKEN(c_p) = NIL;
-#ifdef USE_VM_PROBES
-	 }
-	 DT_UTAG_FLAGS(c_p) &= ~DT_UTAG_SPREADING;
-#endif
-     } else if (ERL_MESSAGE_TOKEN(msgp) != am_undefined) {
-	 Eterm msg;
-	 SEQ_TRACE_TOKEN(c_p) = ERL_MESSAGE_TOKEN(msgp);
-#ifdef USE_VM_PROBES
-	 if (ERL_MESSAGE_TOKEN(msgp) == am_have_dt_utag) {
-	     if (DT_UTAG(c_p) == NIL) {
-		 DT_UTAG(c_p) = ERL_MESSAGE_DT_UTAG(msgp);
-	     }
-	     DT_UTAG_FLAGS(c_p) |= DT_UTAG_SPREADING;
-	 } else {
-#endif
-	     ASSERT(is_tuple(SEQ_TRACE_TOKEN(c_p)));
-	     ASSERT(SEQ_TRACE_TOKEN_ARITY(c_p) == 5);
-	     ASSERT(is_small(SEQ_TRACE_TOKEN_SERIAL(c_p)));
-	     ASSERT(is_small(SEQ_TRACE_TOKEN_LASTCNT(c_p)));
-	     ASSERT(is_small(SEQ_TRACE_TOKEN_FLAGS(c_p)));
-	     ASSERT(is_pid(SEQ_TRACE_TOKEN_SENDER(c_p)));
-	     c_p->seq_trace_lastcnt = unsigned_val(SEQ_TRACE_TOKEN_SERIAL(c_p));
-	     if (c_p->seq_trace_clock < unsigned_val(SEQ_TRACE_TOKEN_SERIAL(c_p))) {
-		 c_p->seq_trace_clock = unsigned_val(SEQ_TRACE_TOKEN_SERIAL(c_p));
-	     }
-	     msg = ERL_MESSAGE_TERM(msgp);
-	     seq_trace_output(SEQ_TRACE_TOKEN(c_p), msg, SEQ_TRACE_RECEIVE, 
-			      c_p->common.id, c_p);
-#ifdef USE_VM_PROBES
-	 }
-#endif
-     }
-#ifdef USE_VM_PROBES
-     if (DTRACE_ENABLED(message_receive)) {
-         Eterm token2 = NIL;
-         DTRACE_CHARBUF(receiver_name, DTRACE_TERM_BUF_SIZE);
-         Sint tok_label = 0;
-         Sint tok_lastcnt = 0;
-         Sint tok_serial = 0;
-
-         dtrace_proc_str(c_p, receiver_name);
-         token2 = SEQ_TRACE_TOKEN(c_p);
-         if (have_seqtrace(token2)) {
-             tok_label = signed_val(SEQ_TRACE_T_LABEL(token2));
-             tok_lastcnt = signed_val(SEQ_TRACE_T_LASTCNT(token2));
-             tok_serial = signed_val(SEQ_TRACE_T_SERIAL(token2));
-         }
-         DTRACE6(message_receive,
-                 receiver_name, size_object(ERL_MESSAGE_TERM(msgp)),
-                 c_p->msg.len - 1, tok_label, tok_lastcnt, tok_serial);
-     }
-#endif
-     UNLINK_MESSAGE(c_p, msgp);
-     JOIN_MESSAGE(c_p);
-     CANCEL_TIMER(c_p);
-
-     erts_save_message_in_proc(c_p, msgp);
-     c_p->flags &= ~F_DELAY_GC;
-
-     if (ERTS_IS_GC_DESIRED_INTERNAL(c_p, HTOP, E)) {
-	 /*
-	  * We want to GC soon but we leave a few
-	  * reductions giving the message some time
-	  * to turn into garbage.
-	  */
-	 ERTS_VBUMP_LEAVE_REDS_INTERNAL(c_p, 5, FCALLS);
-     }
-
-     ERTS_DBG_CHK_REDS(c_p, FCALLS);
-     ERTS_CHK_MBUF_SZ(c_p);
-
-     ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-     PROCESS_MAIN_CHK_LOCKS(c_p);
-     NextPF(0, next);
- }
-
-    /*
-     * Advance the save pointer to the next message (the current
-     * message didn't match), then jump to the loop_rec instruction.
-     */
- OpCase(loop_rec_end_f): {
-
-     ASSERT(c_p->flags & F_DELAY_GC);
-
-     SET_I((BeamInstr *) Arg(0));
-     SAVE_MESSAGE(c_p);
-     if (FCALLS > 0 || FCALLS > neg_o_reds) {
-	 FCALLS--;
-	 goto loop_rec__;
-     }
-
-     c_p->flags &= ~F_DELAY_GC;
-     c_p->i = I;
-     SWAPOUT;
-     c_p->arity = 0;
-     c_p->current = NULL;
-     goto do_schedule;
- }
-    /*
-     * Prepare to wait for a message or a timeout, whichever occurs first.
-     *
-     * Note: In order to keep the compatibility between 32 and 64 bits
-     * emulators, only timeout values that can be represented in 32 bits
-     * (unsigned) or less are allowed.
-     */
-
-
- OpCase(i_wait_timeout_fs): {
-     erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
-
-     /* Fall through */
- }
- OpCase(i_wait_timeout_locked_fs): {
-     Eterm timeout_value;
-
-     /*
-      * If we have already set the timer, we must NOT set it again.  Therefore,
-      * we must test the F_INSLPQUEUE flag as well as the F_TIMO flag.
-      */
-     if (c_p->flags & (F_INSLPQUEUE | F_TIMO)) {
-	 goto wait2;
-     }
-     GetArg1(1, timeout_value);
-     if (timeout_value != make_small(0)) {
-
-	 if (timeout_value == am_infinity)
-	     c_p->flags |= F_TIMO;
-	 else {
-	     int tres = erts_set_proc_timer_term(c_p, timeout_value);
-	     if (tres == 0) {
-		 /*
-		  * The timer routiner will set c_p->i to the value in
-		  * c_p->def_arg_reg[0].  Note that it is safe to use this
-		  * location because there are no living x registers in
-		  * a receive statement.
-		  */
-		 BeamInstr** pi = (BeamInstr**) c_p->def_arg_reg;
-		 *pi = I+3;
-	     }
-	     else { /* Wrong time */
-	     OpCase(i_wait_error_locked): {
-		     erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
-		     /* Fall through */
-		 }
-	     OpCase(i_wait_error): {
-		     c_p->freason = EXC_TIMEOUT_VALUE;
-		     goto find_func_info;
-		 }
-	     }
-	 }
-
-	 /*
-	  * Prepare to wait indefinitely for a new message to arrive
-	  * (or the time set above if falling through from above).
-	  *
-	  * When a new message arrives, control will be transferred
-	  * the loop_rec instruction (at label L1).  In case of
-	  * of timeout, control will be transferred to the timeout
-	  * instruction following the wait_timeout instruction.
-	  */
-
-	 OpCase(wait_locked_f):
-	 OpCase(wait_f):
-
-	 wait2: {
-#ifndef ERTS_SMP
-	     if (ERTS_PROC_IS_EXITING(c_p)) {
-		 /*
-		  * I non smp case:
-		  *
-		  * Currently executing process might be sent an exit
-		  * signal if it is traced by a port that it also is
-		  * linked to, and the port terminates during the
-		  * trace. In this case we do *not* want to clear
-		  * the active flag, which will make the process hang
-		  * in limbo forever.
-		  */
-		 SWAPOUT;
-                 c_p->arity = 0;
-		 goto do_schedule;
-	     }
-#endif
-	     c_p->i = (BeamInstr *) Arg(0); /* L1 */
-	     SWAPOUT;
-	     c_p->arity = 0;
-
-	     if (!ERTS_PTMR_IS_TIMED_OUT(c_p))
-		 erts_smp_atomic32_read_band_relb(&c_p->state,
-						  ~ERTS_PSFLG_ACTIVE);
-	     ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	     erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
-	     c_p->current = NULL;
-	     goto do_schedule;
-	 }
-	 OpCase(wait_unlocked_f): {
-	     erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
-	     goto wait2;
-	 }
-     }
-     erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
-     Next(2);
- }
-
- OpCase(i_wait_timeout_fI): {
-     erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
- }
-
- OpCase(i_wait_timeout_locked_fI):
- {
-     /*
-      * If we have already set the timer, we must NOT set it again.  Therefore,
-      * we must test the F_INSLPQUEUE flag as well as the F_TIMO flag.
-      */
-     if ((c_p->flags & (F_INSLPQUEUE | F_TIMO)) == 0) {
-	 BeamInstr** p = (BeamInstr **) c_p->def_arg_reg;
-	 *p = I+3;
-	 erts_set_proc_timer_uword(c_p, Arg(1));
-     }
-     goto wait2;
- }
-
-    /*
-     * A timeout has occurred.  Reset the save pointer so that the next
-     * receive statement will examine the first message first.
-     */
- OpCase(timeout_locked): {
-     erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
- }
-
- OpCase(timeout): {
-     BeamInstr *next;
-
-     PreFetch(0, next);
-     if (IS_TRACED_FL(c_p, F_TRACE_RECEIVE)) {
-	 trace_receive(c_p, am_clock_service, am_timeout, NULL);
-     }
-     if (ERTS_PROC_GET_SAVED_CALLS_BUF(c_p)) {
-	 save_calls(c_p, &exp_timeout);
-     }
-     c_p->flags &= ~F_TIMO;
-     JOIN_MESSAGE(c_p);
-     NextPF(0, next);
- }
-
- {
-     Eterm select_val2;
-
- OpCase(i_select_tuple_arity2_yfAAff):
-     select_val2 = yb(Arg(0));
-     goto do_select_tuple_arity2;
-
- OpCase(i_select_tuple_arity2_xfAAff):
-     select_val2 = xb(Arg(0));
-     goto do_select_tuple_arity2;
-
- do_select_tuple_arity2:
-     if (is_not_tuple(select_val2)) {
-	 goto select_val2_fail;
-     }
-     select_val2 = *tuple_val(select_val2);
-     goto do_select_val2;
-
- OpCase(i_select_val2_yfccff):
-     select_val2 = yb(Arg(0));
-     goto do_select_val2;
-
- OpCase(i_select_val2_xfccff):
-     select_val2 = xb(Arg(0));
-     goto do_select_val2;
-
- do_select_val2:
-     if (select_val2 == Arg(2)) {
-	 I += 3;
-     } else if (select_val2 == Arg(3)) {
-	 I += 4;
-     }
-
- select_val2_fail:
-     SET_I((BeamInstr *) Arg(1));
-     Goto(*I);
- }
-
- {
-     Eterm select_val;
-
- OpCase(i_select_tuple_arity_xfI):
-     select_val = xb(Arg(0));
-     goto do_select_tuple_arity;
-
- OpCase(i_select_tuple_arity_yfI):
-     select_val = yb(Arg(0));
-     goto do_select_tuple_arity;
-
- do_select_tuple_arity:
-     if (is_tuple(select_val)) {
-	 select_val = *tuple_val(select_val);
-	 goto do_linear_search;
-     }
-     SET_I((BeamInstr *) Arg(1));
-     Goto(*I);
-
- OpCase(i_select_val_lins_xfI):
-     select_val = xb(Arg(0));
-     goto do_linear_search;
-
- OpCase(i_select_val_lins_yfI):
-     select_val = yb(Arg(0));
-     goto do_linear_search;
-
- do_linear_search: {
-     BeamInstr *vs = &Arg(3);
-     int ix = 0;
-
-     for(;;) {
-	 if (vs[ix+0] >= select_val) { ix += 0; break; }
-	 if (vs[ix+1] >= select_val) { ix += 1; break; }
-	 ix += 2;
-     }
-
-     if (vs[ix] == select_val) {
-	 I += ix + Arg(2) + 2;
-     }
-
-     SET_I((BeamInstr *) Arg(1));
-     Goto(*I);
-   }
-
- OpCase(i_select_val_bins_xfI):
-     select_val = xb(Arg(0));
-     goto do_binary_search;
-
- OpCase(i_select_val_bins_yfI):
-     select_val = yb(Arg(0));
-     goto do_binary_search;
-     
- do_binary_search:
- {
-     struct Pairs {
-	 BeamInstr val;
-	 BeamInstr* addr;
-     };
-     struct Pairs* low;
-     struct Pairs* high;
-     struct Pairs* mid;
-     int bdiff; /* int not long because the arrays aren't that large */
-
-     low = (struct Pairs *) &Arg(3);
-     high = low + Arg(2);
-
-     /* The pointer subtraction (high-low) below must produce
-      * a signed result, because high could be < low. That
-      * requires the compiler to insert quite a bit of code.
-      *
-      * However, high will be > low so the result will be
-      * positive. We can use that knowledge to optimise the
-      * entire sequence, from the initial comparison to the
-      * computation of mid.
-      *
-      * -- Mikael Pettersson, Acumem AB
-      *
-      * Original loop control code:
-      *
-      * while (low < high) {
-      *    mid = low + (high-low) / 2;
-      *
-      */
-     while ((bdiff = (int)((char*)high - (char*)low)) > 0) {
-	 unsigned int boffset = ((unsigned int)bdiff >> 1) & ~(sizeof(struct Pairs)-1);
-
-	 mid = (struct Pairs*)((char*)low + boffset);
-	 if (select_val < mid->val) {
-	     high = mid;
-	 } else if (select_val > mid->val) {
-	     low = mid + 1;
-	 } else {
-	     SET_I(mid->addr);
-	     Goto(*I);
-	 }
-     }
-     SET_I((BeamInstr *) Arg(1));
-     Goto(*I);
- }
- }
-
- {
-     Eterm jump_on_val_zero_index;
-     
- OpCase(i_jump_on_val_zero_yfI):
-     jump_on_val_zero_index = yb(Arg(0));
-     goto do_jump_on_val_zero_index;
-
- OpCase(i_jump_on_val_zero_xfI):
-     jump_on_val_zero_index = xb(Arg(0));
-     goto do_jump_on_val_zero_index;
-
- do_jump_on_val_zero_index:
-     if (is_small(jump_on_val_zero_index)) {
-	 jump_on_val_zero_index = signed_val(jump_on_val_zero_index);
-	 if (jump_on_val_zero_index < Arg(2)) {
-	     SET_I((BeamInstr *) (&Arg(3))[jump_on_val_zero_index]);
-	     Goto(*I);
-	 }
-     }
-     SET_I((BeamInstr *) Arg(1));
-     Goto(*I);
- }
-
- {
-     Eterm jump_on_val_index;
-
- 
- OpCase(i_jump_on_val_yfII):
-     jump_on_val_index = yb(Arg(0));
-     goto do_jump_on_val_index;
-
- OpCase(i_jump_on_val_xfII):
-     jump_on_val_index = xb(Arg(0));
-     goto do_jump_on_val_index;
-
- do_jump_on_val_index:
-     if (is_small(jump_on_val_index)) {
-	 jump_on_val_index = (Uint) (signed_val(jump_on_val_index) - Arg(3));
-	 if (jump_on_val_index < Arg(2)) {
-	     SET_I((BeamInstr *) (&Arg(4))[jump_on_val_index]);
-	     Goto(*I);
-	 }
-     }
-     SET_I((BeamInstr *) Arg(1));
-     Goto(*I);
- }
-
- do_put_tuple: {
-     Eterm* hp = HTOP;
-
-     *hp++ = make_arityval(pt_arity);
-
-     do {
-	 Eterm term = *I++;
-	 switch (loader_tag(term)) {
-	 case LOADER_X_REG:
-	     *hp++ = x(loader_x_reg_index(term));
-	     break;
-	 case LOADER_Y_REG:
-	     *hp++ = y(loader_y_reg_index(term));
-	     break;
-	 default:
-	     *hp++ = term;
-	     break;
-	 }
-     } while (--pt_arity != 0);
-     HTOP = hp;
-     Goto(*I);
- }
-
- OpCase(new_map_dII): {
-     Eterm res;
-
-     HEAVY_SWAPOUT;
-     res = new_map(c_p, reg, I-1);
-     HEAVY_SWAPIN;
-     StoreResult(res, Arg(0));
-     Next(3+Arg(2));
- }
-
-#define PUT_TERM_REG(term, desc)		\
-do {						\
-    switch (loader_tag(desc)) {			\
-    case LOADER_X_REG:				\
-	x(loader_x_reg_index(desc)) = (term);	\
-	break;					\
-    case LOADER_Y_REG:				\
-	y(loader_y_reg_index(desc)) = (term);	\
-	break;					\
-    default:					\
-	ASSERT(0);				\
-	break;					\
-    }						\
-} while(0)
-
- OpCase(i_get_map_elements_fsI): {
-    Eterm map;
-    BeamInstr *fs;
-    Uint sz, n;
-
-    GetArg1(1, map);
-
-    /* this instruction assumes Arg1 is a map,
-     * i.e. that it follows a test is_map if needed.
-     */
-
-    n  = (Uint)Arg(2) / 3;
-    fs = &Arg(3); /* pattern fields and target registers */
-
-    if (is_flatmap(map)) {
-	flatmap_t *mp;
-	Eterm *ks;
-	Eterm *vs;
-
-	mp = (flatmap_t *)flatmap_val(map);
-	sz = flatmap_get_size(mp);
-
-	if (sz == 0) {
-	    ClauseFail();
-	}
-
-	ks = flatmap_get_keys(mp);
-	vs = flatmap_get_values(mp);
-
-	while(sz) {
-	    if (EQ((Eterm) fs[0], *ks)) {
-		PUT_TERM_REG(*vs, fs[1]);
-		n--;
-		fs += 3;
-		/* no more values to fetch, we are done */
-		if (n == 0) {
-		    I = fs;
-		    Next(-1);
-		}
-	    }
-	    ks++, sz--, vs++;
-	}
-
-	ClauseFail();
-    } else {
-	const Eterm *v;
-	Uint32 hx;
-	ASSERT(is_hashmap(map));
-	while(n--) {
-	    hx = fs[2];
-	    ASSERT(hx == hashmap_make_hash((Eterm)fs[0]));
-	    if ((v = erts_hashmap_get(hx, (Eterm)fs[0], map)) == NULL) {
-		ClauseFail();
-	    }
-	    PUT_TERM_REG(*v, fs[1]);
-	    fs += 3;
-	}
-	I = fs;
-	Next(-1);
-    }
- }
-#undef PUT_TERM_REG
-
- OpCase(update_map_assoc_jsdII): {
-     Eterm res;
-     Eterm map;
-
-     GetArg1(1, map);
-     HEAVY_SWAPOUT;
-     res = update_map_assoc(c_p, reg, map, I);
-     HEAVY_SWAPIN;
-     if (is_value(res)) {
-	 StoreResult(res, Arg(2));
-	 Next(5+Arg(4));
-     } else {
-	 /*
-	  * This can only happen if the code was compiled
-	  * with the compiler in OTP 17.
-	  */
-	 c_p->freason = BADMAP;
-	 c_p->fvalue = map;
-	 goto lb_Cl_error;
-     }
- }
-
- OpCase(update_map_exact_jsdII): {
-     Eterm res;
-     Eterm map;
-
-     GetArg1(1, map);
-     HEAVY_SWAPOUT;
-     res = update_map_exact(c_p, reg, map, I);
-     HEAVY_SWAPIN;
-     if (is_value(res)) {
-	 StoreResult(res, Arg(2));
-	 Next(5+Arg(4));
-     } else {
-	 goto lb_Cl_error;
-     }
- }
-
-
-    /*
-     * All guards with zero arguments have special instructions:
-     * 	self/0
-     * 	node/0
-     *
-     * All other guard BIFs take one or two arguments.
-     */
-
-    /*
-     * Guard BIF in head.  On failure, ignore the error and jump
-     * to the code for the next clause.  We don't support tracing
-     * of guard BIFs.
-     */
-
- OpCase(bif1_fbsd):
-    {
-	ErtsBifFunc bf;
-	Eterm tmp_reg[1];
-	Eterm result;
-
-	GetArg1(2, tmp_reg[0]);
-	bf = (BifFunction) Arg(1);
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	c_p->fcalls = FCALLS;
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	ERTS_CHK_MBUF_SZ(c_p);
-	result = (*bf)(c_p, tmp_reg, I);
-	ERTS_CHK_MBUF_SZ(c_p);
-	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
-	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ERTS_HOLE_CHECK(c_p);
-	FCALLS = c_p->fcalls;
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	if (is_value(result)) {
-	    StoreBifResult(3, result);
-	}
-	SET_I((BeamInstr *) Arg(0));
-	Goto(*I);
-    }
-
-    /*
-     * Guard BIF in body.  It can fail like any BIF.  No trace support.
-     */
-
- OpCase(bif1_body_bsd):
-    {
-	ErtsBifFunc bf;
-
-	Eterm tmp_reg[1];
-	Eterm result;
-
-	GetArg1(1, tmp_reg[0]);
-	bf = (ErtsBifFunc) Arg(0);
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	c_p->fcalls = FCALLS;
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	ERTS_CHK_MBUF_SZ(c_p);
-	result = (*bf)(c_p, tmp_reg, I);
-	ERTS_CHK_MBUF_SZ(c_p);
-	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
-	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ERTS_HOLE_CHECK(c_p);
-	FCALLS = c_p->fcalls;
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	if (is_value(result)) {
-	    StoreBifResult(2, result);
-	}
-	reg[0] = tmp_reg[0];
-	SWAPOUT;
-	I = handle_error(c_p, I, reg, ubif2mfa((void *) bf));
-	goto post_error_handling;
-    }
-
- OpCase(i_gc_bif1_jIsId):
-    {
-	typedef Eterm (*GcBifFunction)(Process*, Eterm*, Uint);
-	GcBifFunction bf;
-	Eterm result;
-	Uint live = (Uint) Arg(3);
-
-	GetArg1(2, x(live));
-	bf = (GcBifFunction) Arg(1);
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	c_p->fcalls = FCALLS;
-	SWAPOUT;
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
-	ERTS_CHK_MBUF_SZ(c_p);
-	result = (*bf)(c_p, reg, live);
-	ERTS_CHK_MBUF_SZ(c_p);
-	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	SWAPIN;
-	ERTS_HOLE_CHECK(c_p);
-	FCALLS = c_p->fcalls;
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	if (is_value(result)) {
-	    StoreBifResult(4, result);
-	}
-	if (Arg(0) != 0) {
-	    SET_I((BeamInstr *) Arg(0));
-	    Goto(*I);
-	}
-	x(0) = x(live);
-	I = handle_error(c_p, I, reg, gcbif2mfa((void *) bf));
-	goto post_error_handling;
-    }
-
- OpCase(i_gc_bif2_jIIssd): /* Note, one less parameter than the i_gc_bif1
-			    and i_gc_bif3 */
-    {
-	typedef Eterm (*GcBifFunction)(Process*, Eterm*, Uint);
-	GcBifFunction bf;
-	Eterm result;
-	Uint live = (Uint) Arg(2);
-
-	GetArg2(3, x(live), x(live+1));
-	/*
-	 * XXX This calling convention does not make sense. 'live'
-	 * should point out the first argument, not the second
-	 * (i.e. 'live' should not be incremented below).
-	 */
-	live++;
-	bf = (GcBifFunction) Arg(1);
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	c_p->fcalls = FCALLS;
-	SWAPOUT;
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
-	ERTS_CHK_MBUF_SZ(c_p);
-	result = (*bf)(c_p, reg, live);
-	ERTS_CHK_MBUF_SZ(c_p);
-	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	SWAPIN;
-	ERTS_HOLE_CHECK(c_p);
-	FCALLS = c_p->fcalls;
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	if (is_value(result)) {
-	    StoreBifResult(5, result);
-	}
-	if (Arg(0) != 0) {
-	    SET_I((BeamInstr *) Arg(0));
-	    Goto(*I);
-	}
-	live--;
-	x(0) = x(live);
-	x(1) = x(live+1);
-	I = handle_error(c_p, I, reg, gcbif2mfa((void *) bf));
-	goto post_error_handling;
-    }
-
- OpCase(i_gc_bif3_jIIssd):
-    {
-	typedef Eterm (*GcBifFunction)(Process*, Eterm*, Uint);
-	GcBifFunction bf;
-	Eterm result;
-	Uint live = (Uint) Arg(2);
-
-	x(live) = x(SCRATCH_X_REG);
-	GetArg2(3, x(live+1), x(live+2));
-	/*
-	 * XXX This calling convention does not make sense. 'live'
-	 * should point out the first argument, not the third
-	 * (i.e. 'live' should not be incremented below).
-	 */
-	live += 2;
-	bf = (GcBifFunction) Arg(1);
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	c_p->fcalls = FCALLS;
-	SWAPOUT;
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
-	ERTS_CHK_MBUF_SZ(c_p);
-	result = (*bf)(c_p, reg, live);
-	ERTS_CHK_MBUF_SZ(c_p);
-	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	SWAPIN;
-	ERTS_HOLE_CHECK(c_p);
-	FCALLS = c_p->fcalls;
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	if (is_value(result)) {
-	    StoreBifResult(5, result);
-	}
-	if (Arg(0) != 0) {
-	    SET_I((BeamInstr *) Arg(0));
-	    Goto(*I);
-	}
-	live -= 2;
-	x(0) = x(live);
-	x(1) = x(live+1);
-	x(2) = x(live+2);
-	I = handle_error(c_p, I, reg, gcbif2mfa((void *) bf));
-	goto post_error_handling;
-    }
-
- /*
-  * Guards bifs and, or, xor in guards.
-  */
- OpCase(i_bif2_fbssd):
-    {
-	Eterm tmp_reg[2];
-	ErtsBifFunc bf;
-	Eterm result;
-
-	GetArg2(2, tmp_reg[0], tmp_reg[1]);
-	bf = (ErtsBifFunc) Arg(1);
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	c_p->fcalls = FCALLS;
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	ERTS_CHK_MBUF_SZ(c_p);
-	result = (*bf)(c_p, tmp_reg, I);
-	ERTS_CHK_MBUF_SZ(c_p);
-	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
-	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ERTS_HOLE_CHECK(c_p);
-	FCALLS = c_p->fcalls;
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	if (is_value(result)) {
-	    StoreBifResult(4, result);
-	}
-	SET_I((BeamInstr *) Arg(0));
-	Goto(*I);
-    }
-
- /*
-  * Guards bifs and, or, xor, relational operators in body.
-  */
- OpCase(i_bif2_body_bssd):
-    {
-	Eterm tmp_reg[2];
-	ErtsBifFunc bf;
-	Eterm result;
-
-	GetArg2(1, tmp_reg[0], tmp_reg[1]);
-	bf = (ErtsBifFunc) Arg(0);
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	ERTS_CHK_MBUF_SZ(c_p);
-	result = (*bf)(c_p, tmp_reg, I);
-	ERTS_CHK_MBUF_SZ(c_p);
-	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
-	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ERTS_HOLE_CHECK(c_p);
-	if (is_value(result)) {
-	    ASSERT(!is_CP(result));
-	    StoreBifResult(3, result);
-	}
-	reg[0] = tmp_reg[0];
-	reg[1] = tmp_reg[1];
-	SWAPOUT;
-	I = handle_error(c_p, I, reg, ubif2mfa((void *) bf));
-	goto post_error_handling;
-    }
-
-    /*
-     * The most general BIF call.  The BIF may build any amount of data
-     * on the heap.  The result is always returned in r(0).
-     */
- OpCase(call_bif_e):
-    {
-	ErtsBifFunc bf;
-	Eterm result;
-	BeamInstr *next;
-	ErlHeapFragment *live_hf_end;
-        Export *export = (Export*)Arg(0);
-
-
-        if (!((FCALLS - 1) > 0 || (FCALLS-1) > neg_o_reds)) {
-            /* If we have run out of reductions, we do a context
-               switch before calling the bif */
-            c_p->arity = GET_BIF_ARITY(export);
-            c_p->current = &export->info.mfa;
-            goto context_switch3;
-        }
-
-        ERTS_MSACC_SET_BIF_STATE_CACHED_X(
-            GET_BIF_MODULE(export), GET_BIF_ADDRESS(export));
-
-	bf = GET_BIF_ADDRESS(export);
-
-	PRE_BIF_SWAPOUT(c_p);
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	c_p->fcalls = FCALLS - 1;
-	if (FCALLS <= 0) {
-	   save_calls(c_p, export);
-	}
-	PreFetch(1, next);
-	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	live_hf_end = c_p->mbuf;
-	ERTS_CHK_MBUF_SZ(c_p);
-	result = (*bf)(c_p, reg, I);
-	ERTS_CHK_MBUF_SZ(c_p);
-	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
-	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	ERTS_HOLE_CHECK(c_p);
-	ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
-	if (ERTS_IS_GC_DESIRED(c_p)) {
-	    Uint arity = GET_BIF_ARITY(export);
-	    result = erts_gc_after_bif_call_lhf(c_p, live_hf_end, result, reg, arity);
-	    E = c_p->stop;
-	}
-	PROCESS_MAIN_CHK_LOCKS(c_p);
-	HTOP = HEAP_TOP(c_p);
-	FCALLS = c_p->fcalls;
-	ERTS_DBG_CHK_REDS(c_p, FCALLS);
-        /* We have to update the cache if we are enabled in order
-           to make sure no book keeping is done after we disabled
-           msacc. We don't always do this as it is quite expensive. */
-        if (ERTS_MSACC_IS_ENABLED_CACHED_X())
-            ERTS_MSACC_UPDATE_CACHE_X();
-	ERTS_MSACC_SET_STATE_CACHED_M_X(ERTS_MSACC_STATE_EMULATOR);
-	if (is_value(result)) {
-	    r(0) = result;
-	    CHECK_TERM(r(0));
-	    NextPF(1, next);
-	} else if (c_p->freason == TRAP) {
-	    SET_CP(c_p, I+2);
-	    SET_I(c_p->i);
-	    SWAPIN;
-	    Dispatch();
-	}
-
-	/*
-	 * Error handling.  SWAPOUT is not needed because it was done above.
-	 */
-	ASSERT(c_p->stop == E);
-	I = handle_error(c_p, I, reg, &export->info.mfa);
-	goto post_error_handling;
-    }
-
- /*
-  * Arithmetic operations.
-  */
-
- OpCase(i_times_jIssd):
- {
-     Eterm Op1, Op2;
-     GetArg2(2, Op1, Op2);
-     DO_OUTLINED_ARITH_2(mixed_times, Op1, Op2);
- }
-
- OpCase(i_m_div_jIssd):
- {
-     Eterm Op1, Op2;
-     GetArg2(2, Op1, Op2);
-     DO_OUTLINED_ARITH_2(mixed_div, Op1, Op2);
- }
-
- OpCase(i_int_div_jIssd):
- {
-     Eterm Op1, Op2;
-
-     GetArg2(2, Op1, Op2);
-     if (Op2 == SMALL_ZERO) {
-	 goto badarith;
-     } else if (is_both_small(Op1, Op2)) {
-	 Sint ires = signed_val(Op1) / signed_val(Op2);
-	 if (MY_IS_SSMALL(ires)) {
-	     Eterm result = make_small(ires);
-	     StoreBifResult(4, result);
-	 }
-     }
-     DO_OUTLINED_ARITH_2(int_div, Op1, Op2);
- }
-
- {
-     Eterm RemOp1, RemOp2;
-
- OpCase(i_rem_jIxxd):
-     RemOp1 = xb(Arg(2));
-     RemOp2 = xb(Arg(3));
-     goto do_rem;
-
- OpCase(i_rem_jIssd):
-     GetArg2(2, RemOp1, RemOp2);
-     goto do_rem;
-
- do_rem:
-     if (RemOp2 == SMALL_ZERO) {
-         goto badarith;
-     } else if (is_both_small(RemOp1, RemOp2)) {
-         Eterm result = make_small(signed_val(RemOp1) % signed_val(RemOp2));
-         StoreBifResult(4, result);
-     } else {
-	 DO_OUTLINED_ARITH_2(int_rem, RemOp1, RemOp2);
-     }
- }
-
- {
-     Eterm BandOp1, BandOp2;
-
- OpCase(i_band_jIxcd):
-     BandOp1 = xb(Arg(2));
-     BandOp2 = Arg(3);
-     goto do_band;
-
- OpCase(i_band_jIssd):
-     GetArg2(2, BandOp1, BandOp2);
-     goto do_band;
-
- do_band:
-     if (is_both_small(BandOp1, BandOp2)) {
-         /*
-          * No need to untag -- TAG & TAG == TAG.
-          */
-         Eterm result = BandOp1 & BandOp2;
-         StoreBifResult(4, result);
-     }
-     DO_OUTLINED_ARITH_2(band, BandOp1, BandOp2);
- }
-
- /*
-  * An error occurred in an arithmetic operation or test that could
-  * appear either in a head or in a body.
-  * In a head, execution should continue at failure address in Arg(0).
-  * In a body, Arg(0) == 0 and an exception should be raised.
-  */
- lb_Cl_error: {
-     if (Arg(0) != 0) {
-	 OpCase(jump_f): {
-	 jump_f:
-	     SET_I((BeamInstr *) Arg(0));
-	     Goto(*I);
-	 }
-     }
-     ASSERT(c_p->freason != BADMATCH || is_value(c_p->fvalue));
-     goto find_func_info;
- }
-
- OpCase(i_bor_jIssd):
- {
-     Eterm Op1, Op2;
-
-     GetArg2(2, Op1, Op2);
-     if (is_both_small(Op1, Op2)) {
-	 /*
-	  * No need to untag -- TAG | TAG == TAG.
-	  */
-	 Eterm result = Op1 | Op2;
-	 StoreBifResult(4, result);
-     }
-     DO_OUTLINED_ARITH_2(bor, Op1, Op2);
- }
-
- OpCase(i_bxor_jIssd):
- {
-     Eterm Op1, Op2;
-
-     GetArg2(2, Op1, Op2);
-     if (is_both_small(Op1, Op2)) {
-	 /*
-          * TAG ^ TAG == 0.
-          *
-          * Therefore, we perform the XOR operation on the tagged values,
-          * and OR in the tag bits.
-	  */
-	 Eterm result = (Op1 ^ Op2) | make_small(0);
-	 StoreBifResult(4, result);
-     }
-     DO_OUTLINED_ARITH_2(bxor, Op1, Op2);
- }
-
- {
-     Eterm Op1, Op2;
-     Sint i;
-     Sint ires;
-     Eterm* bigp;
-     Eterm tmp_big[2];
-
-     OpCase(i_bsr_jIssd):
-         GetArg2(2, Op1, Op2);
-	 if (is_small(Op2)) {
-	     i = -signed_val(Op2);
-	     if (is_small(Op1)) {
-		 goto small_shift;
-	     } else if (is_big(Op1)) {
-		 if (i == 0) {
-		     StoreBifResult(4, Op1);
-		 }
-		 ires = big_size(Op1);
-		 goto big_shift;
-	     }
-	 } else if (is_big(Op2)) {
-	     /*
-	      * N bsr NegativeBigNum == N bsl MAX_SMALL
-	      * N bsr PositiveBigNum == N bsl MIN_SMALL
-	      */
-	     Op2 = make_small(bignum_header_is_neg(*big_val(Op2)) ?
-				   MAX_SMALL : MIN_SMALL);
-	     goto do_bsl;
-	}
-     goto badarith;
-     
-     OpCase(i_bsl_jIssd):
-         GetArg2(2, Op1, Op2);
- do_bsl:
-	 if (is_small(Op2)) {
-	     i = signed_val(Op2);
-
-	     if (is_small(Op1)) {
-	     small_shift:
-		 ires = signed_val(Op1);
-	     
-		 if (i == 0 || ires == 0) {
-		     StoreBifResult(4, Op1);
-		 } else if (i < 0)  { /* Right shift */
-		     i = -i;
-		     if (i >= SMALL_BITS-1) {
-			 Op1 = (ires < 0) ? SMALL_MINUS_ONE : SMALL_ZERO;
-		     } else {
-			 Op1 = make_small(ires >> i);
-		     }
-		     StoreBifResult(4, Op1);
-		 } else if (i < SMALL_BITS-1) { /* Left shift */
-		     if ((ires > 0 && ((~(Uint)0 << ((SMALL_BITS-1)-i)) & ires) == 0) ||
-			 ((~(Uint)0 << ((SMALL_BITS-1)-i)) & ~ires) == 0) {
-			 Op1 = make_small(ires << i);
-			 StoreBifResult(4, Op1);
-		     }
-		 }
-		 ires = 1; /* big_size(small_to_big(Op1)) */
-
-	     big_shift:
-		 if (i > 0) {	/* Left shift. */
-		     ires += (i / D_EXP);
-		 } else {	/* Right shift. */
-		     if (ires <= (-i / D_EXP))
-			 ires = 3; /* ??? */
-		     else
-			 ires -= (-i / D_EXP);
-		 }
-		 {
-		     ires = BIG_NEED_SIZE(ires+1);
-		     /*
-		      * Slightly conservative check the size to avoid
-		      * allocating huge amounts of memory for bignums that 
-		      * clearly would overflow the arity in the header
-		      * word.
-		      */
-		     if (ires-8 > BIG_ARITY_MAX) {
-			 c_p->freason = SYSTEM_LIMIT;
-			 goto lb_Cl_error;
-		     }
-		     TestHeapPreserve(ires+1, Arg(1), Op1);
-		     if (is_small(Op1)) {
-			 Op1 = small_to_big(signed_val(Op1), tmp_big);
-		     }
-		     bigp = HTOP;
-		     Op1 = big_lshift(Op1, i, bigp);
-		     if (is_big(Op1)) {
-			 HTOP += bignum_header_arity(*HTOP) + 1;
-		     }
-		     HEAP_SPACE_VERIFIED(0);
-		     if (is_nil(Op1)) {
-			 /*
-			  * This result must have been only slight larger
-			  * than allowed since it wasn't caught by the
-			  * previous test.
-			  */
-			 c_p->freason = SYSTEM_LIMIT;
-			 goto lb_Cl_error;
-		     }
-		     ERTS_HOLE_CHECK(c_p);
-		     StoreBifResult(4, Op1);
-		 }
-	     } else if (is_big(Op1)) {
-		 if (i == 0) {
-		     StoreBifResult(4, Op1);
-		 }
-		 ires = big_size(Op1);
-		 goto big_shift;
-	     }
-	 } else if (is_big(Op2)) {
-	     if (bignum_header_is_neg(*big_val(Op2))) {
-		 /*
-		  * N bsl NegativeBigNum is either 0 or -1, depending on
-		  * the sign of N. Since we don't believe this case
-		  * is common, do the calculation with the minimum
-		  * amount of code.
-		  */
-		 Op2 = make_small(MIN_SMALL);
-		 goto do_bsl;
-	     } else if (is_small(Op1) || is_big(Op1)) {
-		 /*
-		  * N bsl PositiveBigNum is too large to represent.
-		  */
-		 c_p->freason = SYSTEM_LIMIT;
-		 goto lb_Cl_error;
-	     }
-	     /* Fall through if the left argument is not an integer. */
-	 }
-     /*
-      * One or more non-integer arguments.
-      */
-     goto badarith;
- }
-
- OpCase(i_int_bnot_jsId):
- {
-     Eterm bnot_val;
-
-     GetArg1(1, bnot_val);
-     if (is_small(bnot_val)) {
-	 bnot_val = make_small(~signed_val(bnot_val));
-     } else {
-	 Uint live = Arg(2);
-	 HEAVY_SWAPOUT;
-	 reg[live] = bnot_val;
-	 bnot_val = erts_gc_bnot(c_p, reg, live);
-	 HEAVY_SWAPIN;
-	 ERTS_HOLE_CHECK(c_p);
-	 if (is_nil(bnot_val)) {
-	     goto lb_Cl_error;
-	 }
-     }
-     StoreBifResult(3, bnot_val);
- }
-
- badarith:
-    c_p->freason = BADARITH;
-    goto lb_Cl_error;
-
- OpCase(i_apply): {
-     BeamInstr *next;
-     HEAVY_SWAPOUT;
-     next = apply(c_p, r(0), x(1), x(2), reg, NULL, 0);
-     HEAVY_SWAPIN;
-     if (next != NULL) {
-	 SET_CP(c_p, I+1);
-	 SET_I(next);
-	 Dispatch();
-     }
-     I = handle_error(c_p, I, reg, &bif_export[BIF_apply_3]->info.mfa);
-     goto post_error_handling;
- }
-
- OpCase(i_apply_last_P): {
-     BeamInstr *next;
-     HEAVY_SWAPOUT;
-     next = apply(c_p, r(0), x(1), x(2), reg, I, Arg(0));
-     HEAVY_SWAPIN;
-     if (next != NULL) {
-	 SET_CP(c_p, (BeamInstr *) E[0]);
-	 E = ADD_BYTE_OFFSET(E, Arg(0));
-	 SET_I(next);
-	 Dispatch();
-     }
-     I = handle_error(c_p, I, reg, &bif_export[BIF_apply_3]->info.mfa);
-     goto post_error_handling;
- }
-
- OpCase(i_apply_only): {
-     BeamInstr *next;
-     HEAVY_SWAPOUT;
-     next = apply(c_p, r(0), x(1), x(2), reg, I, 0);
-     HEAVY_SWAPIN;
-     if (next != NULL) {
-	 SET_I(next);
-	 Dispatch();
-     }
-     I = handle_error(c_p, I, reg, &bif_export[BIF_apply_3]->info.mfa);
-     goto post_error_handling;
- }
 
- OpCase(apply_I): {
-     BeamInstr *next;
-
-     HEAVY_SWAPOUT;
-     next = fixed_apply(c_p, reg, Arg(0), NULL, 0);
-     HEAVY_SWAPIN;
-     if (next != NULL) {
-	 SET_CP(c_p, I+2);
-	 SET_I(next);
-	 Dispatch();
-     }
-     I = handle_error(c_p, I, reg, &bif_export[BIF_apply_3]->info.mfa);
-     goto post_error_handling;
- }
-
- OpCase(apply_last_IP): {
-     BeamInstr *next;
-
-     HEAVY_SWAPOUT;
-     next = fixed_apply(c_p, reg, Arg(0), I, Arg(1));
-     HEAVY_SWAPIN;
-     if (next != NULL) {
-	 SET_CP(c_p, (BeamInstr *) E[0]);
-	 E = ADD_BYTE_OFFSET(E, Arg(1));
-	 SET_I(next);
-	 Dispatch();
-     }
-     I = handle_error(c_p, I, reg, &bif_export[BIF_apply_3]->info.mfa);
-     goto post_error_handling;
- }
-
- OpCase(i_apply_fun): {
-     BeamInstr *next;
-
-     HEAVY_SWAPOUT;
-     next = apply_fun(c_p, r(0), x(1), reg);
-     HEAVY_SWAPIN;
-     if (next != NULL) {
-	 SET_CP(c_p, I+1);
-	 SET_I(next);
-	 Dispatchfun();
-     }
-     goto find_func_info;
- }
-
- OpCase(i_apply_fun_last_P): {
-     BeamInstr *next;
-
-     HEAVY_SWAPOUT;
-     next = apply_fun(c_p, r(0), x(1), reg);
-     HEAVY_SWAPIN;
-     if (next != NULL) {
-	 SET_CP(c_p, (BeamInstr *) E[0]);
-	 E = ADD_BYTE_OFFSET(E, Arg(0));
-	 SET_I(next);
-	 Dispatchfun();
-     }
-     goto find_func_info;
- }
-
- OpCase(i_apply_fun_only): {
-     BeamInstr *next;
-
-     HEAVY_SWAPOUT;
-     next = apply_fun(c_p, r(0), x(1), reg);
-     HEAVY_SWAPIN;
-     if (next != NULL) {
-	 SET_I(next);
-	 Dispatchfun();
-     }
-     goto find_func_info;
- }
-
- OpCase(i_call_fun_I): {
-     BeamInstr *next;
-
-     HEAVY_SWAPOUT;
-     next = call_fun(c_p, Arg(0), reg, THE_NON_VALUE);
-     HEAVY_SWAPIN;
-     if (next != NULL) {
-	 SET_CP(c_p, I+2);
-	 SET_I(next);
-	 Dispatchfun();
-     }
-     goto find_func_info;
- }
-
- OpCase(i_call_fun_last_IP): {
-     BeamInstr *next;
-
-     HEAVY_SWAPOUT;
-     next = call_fun(c_p, Arg(0), reg, THE_NON_VALUE);
-     HEAVY_SWAPIN;
-     if (next != NULL) {
-	SET_CP(c_p, (BeamInstr *) E[0]);
-	E = ADD_BYTE_OFFSET(E, Arg(1));
-	SET_I(next);
-	Dispatchfun();
-     }
-     goto find_func_info;
- }
+#include "beam_hot.h"
 
 #ifdef DEBUG
     /*
@@ -3395,7 +819,7 @@ do {						\
      Eterm* argp;
      int i;
 
-     if (erts_smp_atomic32_read_nob(&c_p->state) & ERTS_PSFLG_EXITING) {
+     if (erts_atomic32_read_nob(&c_p->state) & ERTS_PSFLG_EXITING) {
          c_p->i = beam_exit;
          c_p->arity = 0;
          c_p->current = NULL;
@@ -3452,64 +876,25 @@ do {						\
      goto do_schedule1;
  }
 
- OpCase(set_tuple_element_sdP): {
-     Eterm element;
-     Eterm tuple;
-     BeamInstr *next;
-     Eterm* p;
-     
-     PreFetch(3, next);
-     GetArg1(0, element);
-     tuple = REG_TARGET(Arg(1));
-     ASSERT(is_tuple(tuple));
-     p = (Eterm *) ((unsigned char *) tuple_val(tuple) + Arg(2));
-     *p = element;
-     NextPF(3, next);
- }
+#include "beam_warm.h"
 
  OpCase(normal_exit): {
      SWAPOUT;
      c_p->freason = EXC_NORMAL;
-     c_p->arity = 0;		/* In case this process will never be garbed again. */
-     ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
+     c_p->arity = 0; /* In case this process will ever be garbed again. */
+     ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
      erts_do_exit_process(c_p, am_normal);
-     ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
+     ERTS_REQ_PROC_MAIN_LOCK(c_p);
      goto do_schedule;
  }
 
  OpCase(continue_exit): {
-     ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
+     ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
      erts_continue_exit_process(c_p);
-     ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
+     ERTS_REQ_PROC_MAIN_LOCK(c_p);
      goto do_schedule;
  }
 
- OpCase(i_raise): {
-     Eterm raise_trace = x(2);
-     Eterm raise_value = x(1);
-     struct StackTrace *s;
-
-     c_p->fvalue = raise_value;
-     c_p->ftrace = raise_trace;
-     s = get_trace_from_exc(raise_trace);
-     if (s == NULL) {
-	 c_p->freason = EXC_ERROR;
-     } else {
-	 c_p->freason = PRIMARY_EXCEPTION(s->freason);
-     }
-     goto find_func_info;
- }
-
-    {
-	Eterm badmatch_val;
-
-    OpCase(badmatch_x):
-	badmatch_val = xb(Arg(0));
-	c_p->fvalue = badmatch_val;
-	c_p->freason = BADMATCH;
-    }
- /* Fall through here */
-
  find_func_info: {
      SWAPOUT;
      I = handle_error(c_p, I, reg, NULL);
@@ -3550,194 +935,6 @@ do {						\
      }
  }
 
-    {
-	Eterm nif_bif_result;
-	Eterm bif_nif_arity;
-
-    OpCase(call_nif):
-	{
-	    /*
-	     * call_nif is always first instruction in function:
-	     *
-	     * I[-3]: Module
-	     * I[-2]: Function
-	     * I[-1]: Arity
-	     * I[0]: &&call_nif
-	     * I[1]: Function pointer to NIF function
-	     * I[2]: Pointer to erl_module_nif
-	     * I[3]: Function pointer to dirty NIF
-             *
-             * This layout is determined by the NifExport struct
-	     */
-	    BifFunction vbf;
-	    ErlHeapFragment *live_hf_end;
-            ErtsCodeMFA *codemfa;
-
-	    ERTS_MSACC_SET_STATE_CACHED_M_X(ERTS_MSACC_STATE_NIF);
-
-	    codemfa = erts_code_to_codemfa(I);
-
-            c_p->current = codemfa; /* current and vbf set to please handle_error */
-
-	    DTRACE_NIF_ENTRY(c_p, codemfa);
-
-	    HEAVY_SWAPOUT;
-
-	    PROCESS_MAIN_CHK_LOCKS(c_p);
-	    bif_nif_arity = codemfa->arity;
-	    ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
-
-	    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	    {
-		typedef Eterm NifF(struct enif_environment_t*, int argc, Eterm argv[]);
-		NifF* fp = vbf = (NifF*) I[1];
-		struct enif_environment_t env;
-#ifdef ERTS_SMP
-		ASSERT(c_p->scheduler_data);
-#endif
-		live_hf_end = c_p->mbuf;
-		ERTS_CHK_MBUF_SZ(c_p);
-		erts_pre_nif(&env, c_p, (struct erl_module_nif*)I[2], NULL);
-		nif_bif_result = (*fp)(&env, bif_nif_arity, reg);
-		if (env.exception_thrown)
-		    nif_bif_result = THE_NON_VALUE;
-		erts_post_nif(&env);
-		ERTS_CHK_MBUF_SZ(c_p);
-
-		PROCESS_MAIN_CHK_LOCKS(c_p);
-		ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-		ERTS_MSACC_SET_STATE_CACHED_M_X(ERTS_MSACC_STATE_EMULATOR);
-		ASSERT(!env.exiting);
-		ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	    }
-
-	    DTRACE_NIF_RETURN(c_p, codemfa);
-	    goto apply_bif_or_nif_epilogue;
-	 
-	OpCase(apply_bif):
-	    /*
-	     * At this point, I points to the code[0] in the export entry for
-	     * the BIF:
-	     *
-	     * code[-3]: Module
-	     * code[-2]: Function
-	     * code[-1]: Arity
-	     * code[0]: &&apply_bif
-	     * code[1]: Function pointer to BIF function
-	     */
-
-            if (!((FCALLS - 1) > 0 || (FCALLS - 1) > neg_o_reds)) {
-                /* If we have run out of reductions, we do a context
-                   switch before calling the bif */
-                goto context_switch;
-            }
-
-	    codemfa = erts_code_to_codemfa(I);
-
-            ERTS_MSACC_SET_BIF_STATE_CACHED_X(codemfa->module, (BifFunction)Arg(0));
-
-
-            /* In case we apply process_info/1,2 or load_nif/1 */
-	    c_p->current = codemfa;
-	    c_p->i = I;		/* In case we apply check_process_code/2. */
-	    c_p->arity = 0;		/* To allow garbage collection on ourselves
-					 * (check_process_code/2).
-					 */
-	    DTRACE_BIF_ENTRY(c_p, codemfa);
-
-	    SWAPOUT;
-	    ERTS_DBG_CHK_REDS(c_p, FCALLS - 1);
-	    c_p->fcalls = FCALLS - 1;
-	    vbf = (BifFunction) Arg(0);
-	    PROCESS_MAIN_CHK_LOCKS(c_p);
-	    bif_nif_arity = codemfa->arity;
-            ASSERT(bif_nif_arity <= 4);
-	    ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
-	    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	    {
-		ErtsBifFunc bf = vbf;
-		ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-		live_hf_end = c_p->mbuf;
-		ERTS_CHK_MBUF_SZ(c_p);
-		nif_bif_result = (*bf)(c_p, reg, I);
-		ERTS_CHK_MBUF_SZ(c_p);
-		ASSERT(!ERTS_PROC_IS_EXITING(c_p) ||
-		       is_non_value(nif_bif_result));
-		ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-		PROCESS_MAIN_CHK_LOCKS(c_p);
-	    }
-            /* We have to update the cache if we are enabled in order
-               to make sure no book keeping is done after we disabled
-               msacc. We don't always do this as it is quite expensive. */
-            if (ERTS_MSACC_IS_ENABLED_CACHED_X())
-                ERTS_MSACC_UPDATE_CACHE_X();
-	    ERTS_MSACC_SET_STATE_CACHED_M_X(ERTS_MSACC_STATE_EMULATOR);
-	    DTRACE_BIF_RETURN(c_p, codemfa);
-
-	apply_bif_or_nif_epilogue:
-	    ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
-	    ERTS_HOLE_CHECK(c_p);
-	    if (ERTS_IS_GC_DESIRED(c_p)) {
-		nif_bif_result = erts_gc_after_bif_call_lhf(c_p, live_hf_end,
-							    nif_bif_result,
-							    reg, bif_nif_arity);
-	    }
-	    SWAPIN;  /* There might have been a garbage collection. */
-	    FCALLS = c_p->fcalls;
-	    ERTS_DBG_CHK_REDS(c_p, FCALLS);
-	    if (is_value(nif_bif_result)) {
-		r(0) = nif_bif_result;
-		CHECK_TERM(r(0));
-		SET_I(c_p->cp);
-		c_p->cp = 0;
-		Goto(*I);
-	    } else if (c_p->freason == TRAP) {
-		SET_I(c_p->i);
-		if (c_p->flags & F_HIBERNATE_SCHED) {
-		    c_p->flags &= ~F_HIBERNATE_SCHED;
-		    goto do_schedule;
-		}
-		Dispatch();
-	    }
-	    I = handle_error(c_p, c_p->cp, reg, c_p->current);
-	    goto post_error_handling;
-	}
-    }
-
- OpCase(i_get_sd):
-    {
-	Eterm arg;
-	Eterm result;
-
-	GetArg1(0, arg);
-	result = erts_pd_hash_get(c_p, arg);
-	StoreBifResult(1, result);
-    }
-
- OpCase(i_get_hash_cId):
-    {
-	Eterm arg;
-	Eterm result;
-
-	GetArg1(0, arg);
-	result = erts_pd_hash_get_with_hx(c_p, Arg(1), arg);
-	StoreBifResult(2, result);
-    }
-
-    {
-	Eterm case_end_val;
-
-    OpCase(case_end_x):
-	case_end_val = xb(Arg(0));
-	c_p->fvalue = case_end_val;
-	c_p->freason = EXC_CASE_CLAUSE;
-	goto find_func_info;
-    }
-
- OpCase(if_end):
-    c_p->freason = EXC_IF_CLAUSE;
-    goto find_func_info;
-
  OpCase(i_func_info_IaaI): {
      ErtsCodeInfo *ci = (ErtsCodeInfo*)I;
      c_p->freason = EXC_FUNCTION_CLAUSE;
@@ -3745,1367 +942,8 @@ do {						\
      goto handle_error;
  }
 
- OpCase(try_case_end_s):
-    {
-	Eterm try_case_end_val;
-	GetArg1(0, try_case_end_val);
-	c_p->fvalue = try_case_end_val;
-	c_p->freason = EXC_TRY_CLAUSE;
-	goto find_func_info;
-    }
-
- /*
-  * Construction of binaries using new instructions.
-  */
- {
-     Eterm new_binary;
-     Eterm num_bits_term;
-     Uint num_bits;
-     Uint alloc;
-     Uint num_bytes;
-
-     OpCase(i_bs_init_bits_heap_IIId): {
-	 num_bits = Arg(0);
-	 alloc = Arg(1);
-	 I++;
-	 goto do_bs_init_bits_known;
-     }
-     
-     OpCase(i_bs_init_bits_IId): {
-	 num_bits = Arg(0);
-	 alloc = 0;
-	 goto do_bs_init_bits_known;
-     }
-
-     OpCase(i_bs_init_bits_fail_heap_sIjId): {
-	 GetArg1(0, num_bits_term);
-	 alloc = Arg(1);
-	 I += 2;
-	 goto do_bs_init_bits;
-     }
-
-     OpCase(i_bs_init_bits_fail_yjId): {
-	 num_bits_term = yb(Arg(0));
-	 I++;
-	 alloc = 0;
-	 goto do_bs_init_bits;
-     }
-     OpCase(i_bs_init_bits_fail_xjId): {
-	 num_bits_term = xb(Arg(0));
-	 I++;
-	 alloc = 0;
-     /* FALL THROUGH */
-     }
-
-     /* num_bits_term = Term for number of bits to build (small/big)
-      * alloc = Number of words to allocate on heap
-      * Operands: Fail Live Dst
-      */
-
- do_bs_init_bits:
-     if (is_small(num_bits_term)) {
-	 Sint size = signed_val(num_bits_term);
-	 if (size < 0) {
-	     goto badarg;
-	 }
-	 num_bits = (Uint) size;
-     } else {
-	 Uint bits;
-
-	 if (!term_to_Uint(num_bits_term, &bits)) {
-	     c_p->freason = bits;
-	     goto lb_Cl_error;
-
-	 }
-	 num_bits = (Eterm) bits;
-     }
-
-     /* num_bits = Number of bits to build
-      * alloc = Number of extra words to allocate on heap
-      * Operands: NotUsed Live Dst
-      */
- do_bs_init_bits_known:
-     num_bytes = ((Uint64)num_bits+(Uint64)7) >> 3;
-     if (num_bits & 7) {
-	 alloc += ERL_SUB_BIN_SIZE;
-     }
-     if (num_bytes <= ERL_ONHEAP_BIN_LIMIT) {
-	 alloc += heap_bin_size(num_bytes);
-     } else {
-	 alloc += PROC_BIN_SIZE;
-     }
-     TestHeap(alloc, Arg(1));
-
-     /* num_bits = Number of bits to build
-      * num_bytes = Number of bytes to allocate in the binary
-      * alloc = Total number of words to allocate on heap
-      * Operands: NotUsed NotUsed Dst
-      */
-     if (num_bytes <= ERL_ONHEAP_BIN_LIMIT) {
-	 ErlHeapBin* hb;
-
-	 erts_bin_offset = 0;
-	 erts_writable_bin = 0;
-	 hb = (ErlHeapBin *) HTOP;
-	 HTOP += heap_bin_size(num_bytes);
-	 hb->thing_word = header_heap_bin(num_bytes);
-	 hb->size = num_bytes;
-	 erts_current_bin = (byte *) hb->data;
-	 new_binary = make_binary(hb);
-
-     do_bits_sub_bin:
-	 if (num_bits & 7) {
-	     ErlSubBin* sb;
-
-	     sb = (ErlSubBin *) HTOP;
-	     HTOP += ERL_SUB_BIN_SIZE;
-	     sb->thing_word = HEADER_SUB_BIN;
-	     sb->size = num_bytes - 1;
-	     sb->bitsize = num_bits & 7;
-	     sb->offs = 0;
-	     sb->bitoffs = 0;
-	     sb->is_writable = 0;
-	     sb->orig = new_binary;
-	     new_binary = make_binary(sb);
-	 }
-	 HEAP_SPACE_VERIFIED(0);
-	 StoreBifResult(2, new_binary);
-     } else {
-	 Binary* bptr;
-	 ProcBin* pb;
-
-	 erts_bin_offset = 0;
-	 erts_writable_bin = 0;
-
-	 /*
-	  * Allocate the binary struct itself.
-	  */
-	 bptr = erts_bin_nrml_alloc(num_bytes);
-	 erts_current_bin = (byte *) bptr->orig_bytes;
-
-	 /*
-	  * Now allocate the ProcBin on the heap.
-	  */
-	 pb = (ProcBin *) HTOP;
-	 HTOP += PROC_BIN_SIZE;
-	 pb->thing_word = HEADER_PROC_BIN;
-	 pb->size = num_bytes;
-	 pb->next = MSO(c_p).first;
-	 MSO(c_p).first = (struct erl_off_heap_header*) pb;
-	 pb->val = bptr;
-	 pb->bytes = (byte*) bptr->orig_bytes;
-	 pb->flags = 0;
-	 OH_OVERHEAD(&(MSO(c_p)), pb->size / sizeof(Eterm));
-	 new_binary = make_binary(pb);
-	 goto do_bits_sub_bin;
-     }
- }
-
- {
-     Eterm BsOp1, BsOp2;
-
-     OpCase(i_bs_init_fail_heap_sIjId): {
-	 GetArg1(0, BsOp1);
-	 BsOp2 = Arg(1);
-	 I += 2;
-	 goto do_bs_init;
-     }
-
-     OpCase(i_bs_init_fail_yjId): {
-	 BsOp1 = yb(Arg(0));
-	 BsOp2 = 0;
-	 I++;
-	 goto do_bs_init;
-     }
-
-     OpCase(i_bs_init_fail_xjId): {
-	 BsOp1 = xb(Arg(0));
-	 BsOp2 = 0;
-	 I++;
-     }
-	 /* FALL THROUGH */
-     do_bs_init:
-         if (is_small(BsOp1)) {
-	     Sint size = signed_val(BsOp1);
-	     if (size < 0) {
-		 goto badarg;
-	     }
-	     BsOp1 = (Eterm) size;
-	 } else {
-	     Uint bytes;
-
-	     if (!term_to_Uint(BsOp1, &bytes)) {
-		 c_p->freason = bytes;
-		 goto lb_Cl_error;
-	     }
-	     if ((bytes >> (8*sizeof(Uint)-3)) != 0) {
-		 goto system_limit;
-	     }
-	     BsOp1 = (Eterm) bytes;
-	 }
-	 if (BsOp1 <= ERL_ONHEAP_BIN_LIMIT) {
-	     goto do_heap_bin_alloc;
-	 } else {
-	     goto do_proc_bin_alloc;
-	 }
-
-
-     OpCase(i_bs_init_heap_IIId): {
-	 BsOp1 = Arg(0);
-	 BsOp2 = Arg(1);
-	 I++;
-	 goto do_proc_bin_alloc;
-     }
-
-     OpCase(i_bs_init_IId): {
-	 BsOp1 = Arg(0);
-	 BsOp2 = 0;
-     }
-     /* FALL THROUGH */
-     do_proc_bin_alloc: {
-	 Binary* bptr;
-	 ProcBin* pb;
-
-	 erts_bin_offset = 0;
-	 erts_writable_bin = 0;
-	 TestBinVHeap(BsOp1 / sizeof(Eterm),
-		      BsOp2 + PROC_BIN_SIZE + ERL_SUB_BIN_SIZE, Arg(1));
-
-	 /*
-	  * Allocate the binary struct itself.
-	  */
-	 bptr = erts_bin_nrml_alloc(BsOp1);
-	 erts_current_bin = (byte *) bptr->orig_bytes;
-
-	 /*
-	  * Now allocate the ProcBin on the heap.
-	  */
-	 pb = (ProcBin *) HTOP;
-	 HTOP += PROC_BIN_SIZE;
-	 pb->thing_word = HEADER_PROC_BIN;
-	 pb->size = BsOp1;
-	 pb->next = MSO(c_p).first;
-	 MSO(c_p).first = (struct erl_off_heap_header*) pb;
-	 pb->val = bptr;
-	 pb->bytes = (byte*) bptr->orig_bytes;
-	 pb->flags = 0;
-	 
-	 OH_OVERHEAD(&(MSO(c_p)), BsOp1 / sizeof(Eterm));
-
-	 StoreBifResult(2, make_binary(pb));
-     }
-
-     OpCase(i_bs_init_heap_bin_heap_IIId): {
-	 BsOp1 = Arg(0);
-	 BsOp2 = Arg(1);
-	 I++;
-	 goto do_heap_bin_alloc;
-     }
-
-     OpCase(i_bs_init_heap_bin_IId): {
-	 BsOp1 = Arg(0);
-	 BsOp2 = 0;
-     }
-     /* Fall through */
-     do_heap_bin_alloc:
-	 {
-	     ErlHeapBin* hb;
-	     Uint bin_need;
-
-	     bin_need = heap_bin_size(BsOp1);
-	     erts_bin_offset = 0;
-	     erts_writable_bin = 0;
-	     TestHeap(bin_need+BsOp2+ERL_SUB_BIN_SIZE, Arg(1));
-	     hb = (ErlHeapBin *) HTOP;
-	     HTOP += bin_need;
-	     hb->thing_word = header_heap_bin(BsOp1);
-	     hb->size = BsOp1;
-	     erts_current_bin = (byte *) hb->data;
-	     BsOp1 = make_binary(hb);
-	     StoreBifResult(2, BsOp1);
-	 }
- }
-
- OpCase(bs_add_jssId): {
-     Eterm Op1, Op2;
-     Uint Unit = Arg(3);
-
-     GetArg2(1, Op1, Op2);
-     if (is_both_small(Op1, Op2)) {
-	 Sint Arg1 = signed_val(Op1);
-	 Sint Arg2 = signed_val(Op2);
-
-	 if (Arg1 >= 0 && Arg2 >= 0) {
-	     BsSafeMul(Arg2, Unit, goto system_limit, Op1);
-	     Op1 += Arg1;
-
-	 store_bs_add_result:
-	     if (Op1 <= MAX_SMALL) {
-		 Op1 = make_small(Op1);
-	     } else {
-		 /*
-		  * May generate a heap fragment, but in this
-		  * particular case it is OK, since the value will be
-		  * stored into an x register (the GC will scan x
-		  * registers for references to heap fragments) and
-		  * there is no risk that value can be stored into a
-		  * location that is not scanned for heap-fragment
-		  * references (such as the heap).
-		  */
-		 SWAPOUT;
-		 Op1 = erts_make_integer(Op1, c_p);
-		 HTOP = HEAP_TOP(c_p);
-	     }
-	     StoreBifResult(4, Op1);
-	 }
-	 goto badarg;
-     } else {
-	 Uint a;
-	 Uint b;
-	 Uint c;
-
-	 /*
-	  * Now we know that one of the arguments is
-	  * not a small. We must convert both arguments
-	  * to Uints and check for errors at the same time.
-	  *
-	  * Error checking is tricky.
-	  *
-	  * If one of the arguments is not numeric or
-	  * not positive, the error reason is BADARG.
-	  *
-	  * Otherwise if both arguments are numeric,
-	  * but at least one argument does not fit in
-	  * an Uint, the reason is SYSTEM_LIMIT.
-	  */
-
-	 if (!term_to_Uint(Op1, &a)) {
-	     if (a == BADARG) {
-		 goto badarg;
-	     }
-	     if (!term_to_Uint(Op2, &b)) {
-		 c_p->freason = b;
-		 goto lb_Cl_error;
-	     }
-	     goto system_limit;
-	 } else if (!term_to_Uint(Op2, &b)) {
-	     c_p->freason = b;
-	     goto lb_Cl_error;
-	 }
-
-	 /*
-	  * The arguments are now correct and stored in a and b.
-	  */
-	 
-	 BsSafeMul(b, Unit, goto system_limit, c);
-	 Op1 = a + c;
-	 if (Op1 < a) {
-	     /*
-	      * If the result is less than one of the
-	      * arguments, there must have been an overflow.
-	      */
-	     goto system_limit;
-	 }
-	 goto store_bs_add_result;
-     }
-     /* No fallthrough */
-     ASSERT(0);
- }
-
- OpCase(bs_put_string_II):
-    {
-	BeamInstr *next;
-	PreFetch(2, next);
-	erts_new_bs_put_string(ERL_BITS_ARGS_2((byte *) Arg(1), Arg(0)));
-	NextPF(2, next);
-    }
-
- /*
-  * x(SCRATCH_X_REG);
-  * Operands: Fail ExtraHeap Live Unit Size Dst
-  */
-
- OpCase(i_bs_append_jIIIsd): {
-     Uint live = Arg(2);
-     Uint res;
-     Eterm Size;
-
-     GetArg1(4, Size);
-     HEAVY_SWAPOUT;
-     reg[live] = x(SCRATCH_X_REG);
-     res = erts_bs_append(c_p, reg, live, Size, Arg(1), Arg(3));
-     HEAVY_SWAPIN;
-     if (is_non_value(res)) {
-	 /* c_p->freason is already set (may be either BADARG or SYSTEM_LIMIT). */
-	 goto lb_Cl_error;
-     }
-     StoreBifResult(5, res);
- }
-
- /*
-  * Operands: Fail Size Src Unit Dst
-  */
- OpCase(i_bs_private_append_jIssd): {
-     Eterm res;
-     Eterm Size, Src;
-
-     GetArg2(2, Size, Src);
-     res = erts_bs_private_append(c_p, Src, Size, Arg(1));
-     if (is_non_value(res)) {
-	 /* c_p->freason is already set (may be either BADARG or SYSTEM_LIMIT). */
-	 goto lb_Cl_error;
-     }
-     StoreBifResult(4, res);
- }
-
- OpCase(bs_init_writable): {
-     HEAVY_SWAPOUT;
-     r(0) = erts_bs_init_writable(c_p, r(0));
-     HEAVY_SWAPIN;
-     Next(0);
- }
-
- /*
-  * Calculate the number of bytes needed to encode the source
-  * operarand to UTF-8. If the source operand is invalid (e.g. wrong
-  * type or range) we return a nonsense integer result (0 or 4). We
-  * can get away with that because we KNOW that bs_put_utf8 will do
-  * full error checking.
-  */
- OpCase(i_bs_utf8_size_sd): {
-     Eterm arg;
-     Eterm result;
-
-     GetArg1(0, arg);
-     if (arg < make_small(0x80UL)) {
-	 result = make_small(1);
-     } else if (arg < make_small(0x800UL)) {
-	 result = make_small(2);
-     } else if (arg < make_small(0x10000UL)) {
-	 result = make_small(3);
-     } else {
-	 result = make_small(4);
-     }
-     StoreBifResult(1, result);
- }
-
- OpCase(i_bs_put_utf8_js): {
-     Eterm arg;
-
-     GetArg1(1, arg);
-     if (!erts_bs_put_utf8(ERL_BITS_ARGS_1(arg))) {
-	 goto badarg;
-     }
-     Next(2);
- }
-
- /*
-  * Calculate the number of bytes needed to encode the source
-  * operarand to UTF-8. If the source operand is invalid (e.g. wrong
-  * type or range) we return a nonsense integer result (2 or 4). We
-  * can get away with that because we KNOW that bs_put_utf16 will do
-  * full error checking.
-  */
-
- OpCase(i_bs_utf16_size_sd): {
-     Eterm arg;
-     Eterm result = make_small(2);
-
-     GetArg1(0, arg);
-     if (arg >= make_small(0x10000UL)) {
-	 result = make_small(4);
-     }
-     StoreBifResult(1, result);
- }
-
- OpCase(bs_put_utf16_jIs): {
-     Eterm arg;
-
-     GetArg1(2, arg);
-     if (!erts_bs_put_utf16(ERL_BITS_ARGS_2(arg, Arg(1)))) {
-	 goto badarg;
-     }
-     Next(3);
- }
-
- /*
-  * Only used for validating a value about to be stored in a binary.
-  */
- OpCase(i_bs_validate_unicode_js): {
-     Eterm val;
-
-     GetArg1(1, val);
-
-     /*
-      * There is no need to untag the integer, but it IS necessary
-      * to make sure it is small (if the term is a bignum, it could
-      * slip through the test, and there is no further test that
-      * would catch it, since bit syntax construction silently masks
-      * too big numbers).
-      */
-     if (is_not_small(val) || val > make_small(0x10FFFFUL) ||
-	 (make_small(0xD800UL) <= val && val <= make_small(0xDFFFUL))) {
-	 goto badarg;
-     }
-     Next(2);
- }
-
- /*
-  * Only used for validating a value matched out. 
-  */
- OpCase(i_bs_validate_unicode_retract_jss): {
-	Eterm i; 		/* Integer to validate */
-
-	/*
-	 * There is no need to untag the integer, but it IS necessary
-	 * to make sure it is small (a bignum pointer could fall in
-	 * the valid range).
-	 */
-
-	GetArg1(1, i);
-	if (is_not_small(i) || i > make_small(0x10FFFFUL) ||
-	    (make_small(0xD800UL) <= i && i <= make_small(0xDFFFUL))) {
-	    Eterm ms;		/* Match context */
-	    ErlBinMatchBuffer* mb;
-
-	    GetArg1(2, ms);
-	    mb = ms_matchbuffer(ms);
-	    mb->offset -= 32;
-	    goto badarg;
-	}
-	Next(3);
-    }
-
- /*
-  * Matching of binaries.
-  */
-
- {
-     Eterm header;
-     BeamInstr *next;
-     Uint slots;
-     Eterm context;
-
-     do_start_match:
-	 slots = Arg(2);
-	 if (!is_boxed(context)) {
-	     ClauseFail();
-	 }
-	 PreFetch(4, next);
-	 header = *boxed_val(context);
-	 if (header_is_bin_matchstate(header)) {
-	     ErlBinMatchState* ms = (ErlBinMatchState *) boxed_val(context);
-	     Uint actual_slots = HEADER_NUM_SLOTS(header);
-	     ms->save_offset[0] = ms->mb.offset;
-	     if (actual_slots < slots) {
-		 ErlBinMatchState* dst;
-		 Uint live = Arg(1);
-		 Uint wordsneeded = ERL_BIN_MATCHSTATE_SIZE(slots);
-
-		 TestHeapPreserve(wordsneeded, live, context);
-		 ms = (ErlBinMatchState *) boxed_val(context);
-		 dst = (ErlBinMatchState *) HTOP;
-		 *dst = *ms;
-		 *HTOP = HEADER_BIN_MATCHSTATE(slots);
-		 HTOP += wordsneeded;
-		 HEAP_SPACE_VERIFIED(0);
-		 StoreResult(make_matchstate(dst), Arg(3));
-	     }
-	 } else if (is_binary_header(header)) {
-	     Eterm result;
-	     Uint live = Arg(1);
-	     Uint wordsneeded = ERL_BIN_MATCHSTATE_SIZE(slots);
-	     TestHeapPreserve(wordsneeded, live, context);
-	     HEAP_TOP(c_p) = HTOP;
-#ifdef DEBUG
-	     c_p->stop = E;	/* Needed for checking in HeapOnlyAlloc(). */
-#endif
-	     result = erts_bs_start_match_2(c_p, context, slots);
-	     HTOP = HEAP_TOP(c_p);
-	     HEAP_SPACE_VERIFIED(0);
-	     if (is_non_value(result)) {
-		 ClauseFail();
-	     } else {
-		 StoreResult(result, Arg(3));
-	     }
-	 } else {
-	     ClauseFail();
-	 }
-	 NextPF(4, next);
-
-     OpCase(i_bs_start_match2_xfIId): {
-	 context = xb(Arg(0));
-	 I++;
-	 goto do_start_match;
-     }
-     OpCase(i_bs_start_match2_yfIId): {
-	 context = yb(Arg(0));
-	 I++;
-	 goto do_start_match;
-     }
- }
-
- OpCase(bs_test_zero_tail2_fx): {
-     BeamInstr *next;
-     ErlBinMatchBuffer *_mb;
-     
-     PreFetch(2, next);
-     _mb = (ErlBinMatchBuffer*) ms_matchbuffer(xb(Arg(1)));
-     if (_mb->size != _mb->offset) {
-	 ClauseFail();
-     }
-     NextPF(2, next);
- }
-
- OpCase(bs_test_tail_imm2_fxI): {
-     BeamInstr *next;
-     ErlBinMatchBuffer *_mb;
-     PreFetch(3, next);
-     _mb = ms_matchbuffer(xb(Arg(1)));
-     if (_mb->size - _mb->offset != Arg(2)) {
-	 ClauseFail();
-     }
-     NextPF(3, next);
- }
-
- OpCase(bs_test_unit_fxI): {
-     BeamInstr *next;
-     ErlBinMatchBuffer *_mb;
-     PreFetch(3, next);
-     _mb = ms_matchbuffer(xb(Arg(1)));
-     if ((_mb->size - _mb->offset) % Arg(2)) {
-	 ClauseFail();
-     }
-     NextPF(3, next);
- }
-
- OpCase(bs_test_unit8_fx): {
-     BeamInstr *next;
-     ErlBinMatchBuffer *_mb;
-     PreFetch(2, next);
-     _mb = ms_matchbuffer(xb(Arg(1)));
-     if ((_mb->size - _mb->offset) & 7) {
-	 ClauseFail();
-     }
-     NextPF(2, next);
- }
-
- {
-     Eterm bs_get_integer8_context;
-
- OpCase(i_bs_get_integer_8_xfd): {
-	 ErlBinMatchBuffer *_mb;
-	 Eterm _result;
-	 bs_get_integer8_context = xb(Arg(0));
-	 I++;
-	 _mb = ms_matchbuffer(bs_get_integer8_context);
-	 if (_mb->size - _mb->offset < 8) {
-	     ClauseFail();
-	 }
-	 if (BIT_OFFSET(_mb->offset) != 0) {
-	     _result = erts_bs_get_integer_2(c_p, 8, 0, _mb);
-	 } else {
-	     _result = make_small(_mb->base[BYTE_OFFSET(_mb->offset)]);
-	     _mb->offset += 8;
-	 }
-	 StoreBifResult(1, _result);
-     }
- }
-
- {
-     Eterm bs_get_integer_16_context;
-
- OpCase(i_bs_get_integer_16_xfd):
-     bs_get_integer_16_context = xb(Arg(0));
-     I++;
-
-     {
-	 ErlBinMatchBuffer *_mb;
-	 Eterm _result;
-	 _mb = ms_matchbuffer(bs_get_integer_16_context);
-	 if (_mb->size - _mb->offset < 16) {
-	     ClauseFail(); 
-	 }
-	 if (BIT_OFFSET(_mb->offset) != 0) {
-	     _result = erts_bs_get_integer_2(c_p, 16, 0, _mb);
-	 } else {
-	     _result = make_small(get_int16(_mb->base+BYTE_OFFSET(_mb->offset)));
-	     _mb->offset += 16;
-	 }
-	 StoreBifResult(1, _result);
-     }
- }
-
- {
-     Eterm bs_get_integer_32_context;
-
- OpCase(i_bs_get_integer_32_xfId):
-     bs_get_integer_32_context = xb(Arg(0));
-     I++;
-
-     {
-	 ErlBinMatchBuffer *_mb;
-	 Uint32 _integer;
-	 Eterm _result;
-	 _mb = ms_matchbuffer(bs_get_integer_32_context);
-	 if (_mb->size - _mb->offset < 32) { ClauseFail(); }
-	 if (BIT_OFFSET(_mb->offset) != 0) {
-	     _integer = erts_bs_get_unaligned_uint32(_mb);
-	 } else {
-	     _integer = get_int32(_mb->base + _mb->offset/8);
-	 }
-	 _mb->offset += 32;
-#if !defined(ARCH_64)
-	 if (IS_USMALL(0, _integer)) {
-#endif
-	     _result = make_small(_integer);
-#if !defined(ARCH_64)
-	 } else {
-	     TestHeap(BIG_UINT_HEAP_SIZE, Arg(1));
-	     _result = uint_to_big((Uint) _integer, HTOP);
-	     HTOP += BIG_UINT_HEAP_SIZE;
-	     HEAP_SPACE_VERIFIED(0);
-	 }
-#endif
-	 StoreBifResult(2, _result);
-     }
- }
-
- {
-     Eterm Ms, Sz;
-
-     /* Operands: x(Reg) Size Live Fail Flags Dst */
- OpCase(i_bs_get_integer_imm_xIIfId): {
-	 Uint wordsneeded;
-	 Ms = xb(Arg(0));
-	 Sz = Arg(1);
-	 wordsneeded = 1+WSIZE(NBYTES(Sz));
-	 TestHeapPreserve(wordsneeded, Arg(2), Ms);
-	 I += 3;
-	 /* Operands: Fail Flags Dst */
-	 goto do_bs_get_integer_imm;
-     }
-
-     /* Operands: x(Reg) Size Fail Flags Dst */
- OpCase(i_bs_get_integer_small_imm_xIfId): {
-	 Ms = xb(Arg(0));
-	 Sz = Arg(1);
-	 I += 2;
-	 /* Operands: Fail Flags Dst */
-	 goto do_bs_get_integer_imm;
-     }
- 
-     /*
-      * Ms = match context
-      * Sz = size of field
-      * Operands: Fail Flags Dst
-      */
- do_bs_get_integer_imm: {
-	 ErlBinMatchBuffer* mb;
-	 Eterm result;
-
-	 mb = ms_matchbuffer(Ms);
-	 LIGHT_SWAPOUT;
-	 result = erts_bs_get_integer_2(c_p, Sz, Arg(1), mb);
-	 LIGHT_SWAPIN;
-	 HEAP_SPACE_VERIFIED(0);
-	 if (is_non_value(result)) {
-	     ClauseFail();
-	 }
-	 StoreBifResult(2, result);
-     }
- }
-
- /*
-  * Operands: Fail Live FlagsAndUnit Ms Sz Dst
-  */
- OpCase(i_bs_get_integer_fIIssd): {
-     Uint flags;
-     Uint size;
-     Eterm Ms;
-     Eterm Sz;
-     ErlBinMatchBuffer* mb;
-     Eterm result;
-
-     flags = Arg(2);
-     GetArg2(3, Ms, Sz);
-     BsGetFieldSize(Sz, (flags >> 3), ClauseFail(), size);
-     if (size >= SMALL_BITS) {
-	 Uint wordsneeded;
-	 /* Check bits size before potential gc.
-	  * We do not want a gc and then realize we don't need
-	  * the allocated space (i.e. if the op fails).
-	  *
-	  * Remember to re-acquire the matchbuffer after gc.
-	  */
-
-	 mb = ms_matchbuffer(Ms);
-	 if (mb->size - mb->offset < size) {
-	     ClauseFail();
-	 }
-	 wordsneeded = 1+WSIZE(NBYTES((Uint) size));
-	 TestHeapPreserve(wordsneeded, Arg(1), Ms);
-     }
-     mb = ms_matchbuffer(Ms);
-     LIGHT_SWAPOUT;
-     result = erts_bs_get_integer_2(c_p, size, flags, mb);
-     LIGHT_SWAPIN;
-     HEAP_SPACE_VERIFIED(0);
-     if (is_non_value(result)) {
-	 ClauseFail();
-     }
-     StoreBifResult(5, result);
- }
-
- {
-     Eterm get_utf8_context;
-
-     /* Operands: MatchContext Fail Dst */
- OpCase(i_bs_get_utf8_xfd): {
-	 get_utf8_context = xb(Arg(0));
-	 I++;
-     }
-
-     /*
-      * get_utf8_context = match_context
-      * Operands: Fail Dst
-      */
-
-     {
-	 Eterm result = erts_bs_get_utf8(ms_matchbuffer(get_utf8_context));
-	 if (is_non_value(result)) {
-	     ClauseFail();
-	 }
-	 StoreBifResult(1, result);
-     }
- }
-
- {
-     Eterm get_utf16_context;
-
-     /* Operands: MatchContext Fail Flags Dst */
-     OpCase(i_bs_get_utf16_xfId): {
-	 get_utf16_context = xb(Arg(0));
-	 I++;
-     }
-
-     /*
-      * get_utf16_context = match_context
-      * Operands: Fail Flags Dst
-      */
-     {
-	 Eterm result = erts_bs_get_utf16(ms_matchbuffer(get_utf16_context),
-					  Arg(1));
-	 if (is_non_value(result)) {
-	     ClauseFail();
-	 }
-	 StoreBifResult(2, result);
-     }
- }
-
- {
-     Eterm context_to_binary_context;
-     ErlBinMatchBuffer* mb;
-     ErlSubBin* sb;
-     Uint size;
-     Uint offs;
-     Uint orig;
-     Uint hole_size;
-
-     OpCase(bs_context_to_binary_x):
-	 context_to_binary_context = xb(Arg(0));
-	 I--;
-
-     if (is_boxed(context_to_binary_context) &&
-	 header_is_bin_matchstate(*boxed_val(context_to_binary_context))) {
-	 ErlBinMatchState* ms;
-	 ms = (ErlBinMatchState *) boxed_val(context_to_binary_context);
-	 mb = &ms->mb;
-	 offs = ms->save_offset[0];
-	 size = mb->size - offs;
-	 goto do_bs_get_binary_all_reuse_common;
-     }
-     Next(2);
-
-     OpCase(i_bs_get_binary_all_reuse_xfI): {
-	 context_to_binary_context = xb(Arg(0));
-	 I++;
-     }
-
-     mb = ms_matchbuffer(context_to_binary_context);
-     size = mb->size - mb->offset;
-     if (size % Arg(1) != 0) {
-	 ClauseFail();
-     }
-     offs = mb->offset;
-
- do_bs_get_binary_all_reuse_common:
-     orig = mb->orig;
-     sb = (ErlSubBin *) boxed_val(context_to_binary_context);
-     hole_size = 1 + header_arity(sb->thing_word) - ERL_SUB_BIN_SIZE;
-     sb->thing_word = HEADER_SUB_BIN;
-     sb->size = BYTE_OFFSET(size);
-     sb->bitsize = BIT_OFFSET(size);
-     sb->offs = BYTE_OFFSET(offs);
-     sb->bitoffs = BIT_OFFSET(offs);
-     sb->is_writable = 0;
-     sb->orig = orig;
-     if (hole_size) {
-	 sb[1].thing_word = make_pos_bignum_header(hole_size-1);
-     }
-     Next(2);
- }
-
- {
-     Eterm match_string_context;
-
-     OpCase(i_bs_match_string_xfII): {
-	 match_string_context = xb(Arg(0));
-	 I++;
-     }
-
-     {
-	 BeamInstr *next;
-	 byte* bytes;
-	 Uint bits;
-	 ErlBinMatchBuffer* mb;
-	 Uint offs;
-
-	 PreFetch(3, next);
-	 bits = Arg(1);
-	 bytes = (byte *) Arg(2);
-	 mb = ms_matchbuffer(match_string_context);
-	 if (mb->size - mb->offset < bits) {
-	     ClauseFail();
-	 }
-	 offs = mb->offset & 7;
-	 if (offs == 0 && (bits & 7) == 0) {
-	     if (sys_memcmp(bytes, mb->base+(mb->offset>>3), bits>>3)) {
-		 ClauseFail();
-	     }
-	 } else if (erts_cmp_bits(bytes, 0, mb->base+(mb->offset>>3), mb->offset & 7, bits)) {
-	     ClauseFail();
-	 }
-	 mb->offset += bits;
-	 NextPF(3, next);
-     }
- }
-
- OpCase(i_bs_save2_xI): {
-     BeamInstr *next;
-     ErlBinMatchState *_ms;
-     PreFetch(2, next);
-     _ms = (ErlBinMatchState*) boxed_val((Eterm) xb(Arg(0)));
-     _ms->save_offset[Arg(1)] = _ms->mb.offset;
-     NextPF(2, next);
- }
-
- OpCase(i_bs_restore2_xI): {
-     BeamInstr *next;
-     ErlBinMatchState *_ms;
-     PreFetch(2, next);
-     _ms = (ErlBinMatchState*) boxed_val((Eterm) xb(Arg(0)));
-     _ms->mb.offset = _ms->save_offset[Arg(1)];
-     NextPF(2, next);
- }
-
 #include "beam_cold.h"
 
-
- /*
-  * This instruction is probably never used (because it is combined with a
-  * a return). However, a future compiler might for some reason emit a
-  * deallocate not followed by a return, and that should work.
-  */
- OpCase(deallocate_I): {
-     BeamInstr *next;
-
-     PreFetch(1, next);
-     D(Arg(0));
-     NextPF(1, next);
- }
-
-    /*
-     * Trace and debugging support.
-     */
-
- OpCase(return_trace): {
-     ErtsCodeMFA* mfa = (ErtsCodeMFA *)(E[0]);
-     
-     SWAPOUT;		/* Needed for shared heap */
-     ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
-     erts_trace_return(c_p, mfa, r(0), ERTS_TRACER_FROM_ETERM(E+1)/* tracer */);
-     ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
-     SWAPIN;
-     c_p->cp = NULL;
-     SET_I((BeamInstr *) cp_val(E[2]));
-     E += 3;
-     Goto(*I);
- }
-
- OpCase(i_generic_breakpoint): {
-     BeamInstr real_I;
-     HEAVY_SWAPOUT;
-     real_I = erts_generic_breakpoint(c_p, erts_code_to_codeinfo(I), reg);
-     HEAVY_SWAPIN;
-     ASSERT(VALID_INSTR(real_I));
-     Goto(real_I);
- }
-
- OpCase(i_return_time_trace): {
-     BeamInstr *pc = (BeamInstr *) (UWord) E[0];
-     SWAPOUT;
-     erts_trace_time_return(c_p, erts_code_to_codeinfo(pc));
-     SWAPIN;
-     c_p->cp = NULL;
-     SET_I((BeamInstr *) cp_val(E[1]));
-     E += 2;
-     Goto(*I);
- }
-
- OpCase(i_return_to_trace): {
-     if (IS_TRACED_FL(c_p, F_TRACE_RETURN_TO)) {
-	 Uint *cpp = (Uint*) E;
-	 for(;;) {
-	     ASSERT(is_CP(*cpp));
-	     if (*cp_val(*cpp) == (BeamInstr) OpCode(return_trace)) {
-		 do ++cpp; while(is_not_CP(*cpp));
-		 cpp += 2;
-	     } else if (*cp_val(*cpp) == (BeamInstr) OpCode(i_return_to_trace)) {
-		 do ++cpp; while(is_not_CP(*cpp));
-	     } else break;
-	 }
-	 SWAPOUT;		/* Needed for shared heap */
-	 ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
-	 erts_trace_return_to(c_p, cp_val(*cpp));
-	 ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
-	 SWAPIN;
-     }
-     c_p->cp = NULL;
-     SET_I((BeamInstr *) cp_val(E[0]));
-     E += 1;
-     Goto(*I);
- }
-
- /*
-  * New floating point instructions.
-  */
-
- OpCase(fmove_ql): {
-     Eterm fr = Arg(1);
-     BeamInstr *next;
-
-     PreFetch(2, next);
-     GET_DOUBLE(Arg(0), *(FloatDef*)ADD_BYTE_OFFSET(freg, fr));
-     NextPF(2, next);
- }
-
- OpCase(fmove_dl): {
-     Eterm targ1;
-     Eterm fr = Arg(1);
-     BeamInstr *next;
-
-     PreFetch(2, next);
-     targ1 = REG_TARGET(Arg(0));
-     /* Arg(0) == HEADER_FLONUM */
-     GET_DOUBLE(targ1, *(FloatDef*)ADD_BYTE_OFFSET(freg, fr));
-     NextPF(2, next);
- }
-
- OpCase(fmove_ld): {
-     Eterm fr = Arg(0);
-     Eterm dest = make_float(HTOP);
-
-     PUT_DOUBLE(*(FloatDef*)ADD_BYTE_OFFSET(freg, fr), HTOP);
-     HTOP += FLOAT_SIZE_OBJECT;
-     StoreBifResult(1, dest);
- }
-
- OpCase(fconv_dl): {
-     Eterm targ1;
-     Eterm fr = Arg(1);
-     BeamInstr *next;
-
-     targ1 = REG_TARGET(Arg(0));
-     PreFetch(2, next);
-     if (is_small(targ1)) {
-	 fb(fr) = (double) signed_val(targ1);
-     } else if (is_big(targ1)) {
-	 if (big_to_double(targ1, &fb(fr)) < 0) {
-	     goto fbadarith;
-	 }
-     } else if (is_float(targ1)) {
-	 GET_DOUBLE(targ1, *(FloatDef*)ADD_BYTE_OFFSET(freg, fr));
-     } else {
-	 goto fbadarith;
-     }
-     NextPF(2, next);
- }
-
-#ifdef NO_FPE_SIGNALS
-     OpCase(fclearerror):
-     OpCase(i_fcheckerror):
-	 erts_exit(ERTS_ERROR_EXIT, "fclearerror/i_fcheckerror without fpe signals (beam_emu)");
-#  define ERTS_NO_FPE_CHECK_INIT ERTS_FP_CHECK_INIT
-#  define ERTS_NO_FPE_ERROR ERTS_FP_ERROR
-#else
-#  define ERTS_NO_FPE_CHECK_INIT(p)
-#  define ERTS_NO_FPE_ERROR(p, a, b)
-
-     OpCase(fclearerror): {
-	 BeamInstr *next;
-
-	 PreFetch(0, next);
-	 ERTS_FP_CHECK_INIT(c_p);
-	 NextPF(0, next);
-     }
-
-     OpCase(i_fcheckerror): {
-	 BeamInstr *next;
-
-	 PreFetch(0, next);
-	 ERTS_FP_ERROR(c_p, freg[0].fd, goto fbadarith);
-	 NextPF(0, next);
-     }
-#endif
-
-
- OpCase(i_fadd_lll): {
-     BeamInstr *next;
-
-     PreFetch(3, next);
-     ERTS_NO_FPE_CHECK_INIT(c_p);
-     fb(Arg(2)) = fb(Arg(0)) + fb(Arg(1));
-     ERTS_NO_FPE_ERROR(c_p, fb(Arg(2)), goto fbadarith);
-     NextPF(3, next);
- }
- OpCase(i_fsub_lll): {
-     BeamInstr *next;
-
-     PreFetch(3, next);
-     ERTS_NO_FPE_CHECK_INIT(c_p);
-     fb(Arg(2)) = fb(Arg(0)) - fb(Arg(1));
-     ERTS_NO_FPE_ERROR(c_p, fb(Arg(2)), goto fbadarith);
-     NextPF(3, next);
- }
- OpCase(i_fmul_lll): {
-     BeamInstr *next;
-
-     PreFetch(3, next);
-     ERTS_NO_FPE_CHECK_INIT(c_p);
-     fb(Arg(2)) = fb(Arg(0)) * fb(Arg(1));
-     ERTS_NO_FPE_ERROR(c_p, fb(Arg(2)), goto fbadarith);
-     NextPF(3, next);
- }
- OpCase(i_fdiv_lll): {
-     BeamInstr *next;
-
-     PreFetch(3, next);
-     ERTS_NO_FPE_CHECK_INIT(c_p);
-     fb(Arg(2)) = fb(Arg(0)) / fb(Arg(1));
-     ERTS_NO_FPE_ERROR(c_p, fb(Arg(2)), goto fbadarith);
-     NextPF(3, next);
- }
- OpCase(i_fnegate_ll): {
-     BeamInstr *next;
-
-     PreFetch(2, next);
-     ERTS_NO_FPE_CHECK_INIT(c_p);
-     fb(Arg(1)) = -fb(Arg(0));
-     ERTS_NO_FPE_ERROR(c_p, fb(Arg(1)), goto fbadarith);
-     NextPF(2, next);
-
- fbadarith:
-     c_p->freason = BADARITH;
-     goto find_func_info;
- }
-
-#ifdef HIPE
- {
-#define HIPE_MODE_SWITCH(Cmd)			\
-     SWAPOUT;					\
-     ERTS_DBG_CHK_REDS(c_p, FCALLS);		\
-     c_p->fcalls = FCALLS;			\
-     c_p->def_arg_reg[4] = -neg_o_reds;		\
-     c_p = hipe_mode_switch(c_p, Cmd, reg);     \
-     goto L_post_hipe_mode_switch
-
-     OpCase(hipe_trap_call): {
-	 /*
-	  * I[-5]: &&lb_i_func_info_IaaI
-	  * I[-4]: Native code callee (inserted by HiPE)
-	  * I[-3]: Module (tagged atom)
-	  * I[-2]: Function (tagged atom)
-	  * I[-1]: Arity (untagged integer)
-	  * I[ 0]: &&lb_hipe_trap_call
-	  * ... remainder of original BEAM code
-	  */
-         ErtsCodeInfo *ci = erts_code_to_codeinfo(I);
-	 ASSERT(ci->op == (Uint) OpCode(i_func_info_IaaI));
-	 c_p->hipe.u.ncallee = ci->u.ncallee;
-	 ++hipe_trap_count;
-	 HIPE_MODE_SWITCH(HIPE_MODE_SWITCH_CMD_CALL | (ci->mfa.arity << 8));
-     }
-     OpCase(hipe_trap_call_closure): {
-       ErtsCodeInfo *ci = erts_code_to_codeinfo(I);
-       ASSERT(ci->op == (Uint) OpCode(i_func_info_IaaI));
-       c_p->hipe.u.ncallee = ci->u.ncallee;
-       ++hipe_trap_count;
-       HIPE_MODE_SWITCH(HIPE_MODE_SWITCH_CMD_CALL_CLOSURE | (ci->mfa.arity << 8));
-     }
-     OpCase(hipe_trap_return): {
-	 HIPE_MODE_SWITCH(HIPE_MODE_SWITCH_CMD_RETURN);
-     }
-     OpCase(hipe_trap_throw): {
-	 HIPE_MODE_SWITCH(HIPE_MODE_SWITCH_CMD_THROW);
-     }
-     OpCase(hipe_trap_resume): {
-	 HIPE_MODE_SWITCH(HIPE_MODE_SWITCH_CMD_RESUME);
-     }
-#undef HIPE_MODE_SWITCH
-
- L_post_hipe_mode_switch:
-#ifdef DEBUG
-     pid = c_p->common.id; /* may have switched process... */
-#endif
-     reg = erts_proc_sched_data(c_p)->x_reg_array;
-     freg = erts_proc_sched_data(c_p)->f_reg_array;
-     ERL_BITS_RELOAD_STATEP(c_p);
-     /* XXX: this abuse of def_arg_reg[] is horrid! */
-     neg_o_reds = -c_p->def_arg_reg[4];
-     FCALLS = c_p->fcalls;
-     SWAPIN;
-     ERTS_DBG_CHK_REDS(c_p, FCALLS);
-     switch( c_p->def_arg_reg[3] ) {
-       case HIPE_MODE_SWITCH_RES_RETURN:
-	 ASSERT(is_value(reg[0]));
-	 SET_I(c_p->cp);
-	 c_p->cp = 0;
-	 Goto(*I);
-       case HIPE_MODE_SWITCH_RES_CALL_EXPORTED:
-	 c_p->i = c_p->hipe.u.callee_exp->addressv[erts_active_code_ix()];
-	 /*fall through*/
-       case HIPE_MODE_SWITCH_RES_CALL_BEAM:
-	 SET_I(c_p->i);
-	 Dispatch();
-       case HIPE_MODE_SWITCH_RES_CALL_CLOSURE:
-	 /* This can be used to call any function value, but currently it's
-	    only used to call closures referring to unloaded modules. */
-	 {
-	     BeamInstr *next;
-
-	     next = call_fun(c_p, c_p->arity - 1, reg, THE_NON_VALUE);
-	     HEAVY_SWAPIN;
-	     if (next != NULL) {
-		 SET_I(next);
-		 Dispatchfun();
-	     }
-	     goto find_func_info;
-	 }
-       case HIPE_MODE_SWITCH_RES_THROW:
-	 c_p->cp = NULL;
-	 I = handle_error(c_p, I, reg, NULL);
-	 goto post_error_handling;
-       default:
-	 erts_exit(ERTS_ERROR_EXIT, "hipe_mode_switch: result %u\n", c_p->def_arg_reg[3]);
-     }
- }
- OpCase(hipe_call_count): {
-     /*
-      * I[-5]: &&lb_i_func_info_IaaI
-      * I[-4]: pointer to struct hipe_call_count (inserted by HiPE)
-      * I[-3]: Module (tagged atom)
-      * I[-2]: Function (tagged atom)
-      * I[-1]: Arity (untagged integer)
-      * I[ 0]: &&lb_hipe_call_count
-      * ... remainder of original BEAM code
-      */
-     ErtsCodeInfo *ci = erts_code_to_codeinfo(I);
-     struct hipe_call_count *hcc = ci->u.hcc;
-     ASSERT(ci->op == (Uint) OpCode(i_func_info_IaaI));
-     ASSERT(hcc != NULL);
-     ASSERT(VALID_INSTR(hcc->opcode));
-     ++(hcc->count);
-     Goto(hcc->opcode);
- }
-#endif /* HIPE */
-
- OpCase(i_yield):
- {
-     /* This is safe as long as REDS_IN(c_p) is never stored 
-      * in c_p->arg_reg[0]. It is currently stored in c_p->def_arg_reg[5],
-      * which may be c_p->arg_reg[5], which is close, but no banana.
-      */
-     c_p->arg_reg[0] = am_true;
-     c_p->arity = 1; /* One living register (the 'true' return value) */
-     SWAPOUT;
-     c_p->i = I + 1; /* Next instruction */
-     c_p->current = NULL;
-     goto do_schedule;
- }
-
- OpCase(i_hibernate): {
-     HEAVY_SWAPOUT;
-     if (erts_hibernate(c_p, r(0), x(1), x(2), reg)) {
-	 FCALLS = c_p->fcalls;
-	 c_p->flags &= ~F_HIBERNATE_SCHED;
-	 goto do_schedule;
-     } else {
-	 HEAVY_SWAPIN;
-	 I = handle_error(c_p, I, reg, &bif_export[BIF_hibernate_3]->info.mfa);
-	 goto post_error_handling;
-     }
- }
-
- /* This is optimised as an instruction because
-    it has to be very very fast */
- OpCase(i_perf_counter): {
-    BeamInstr* next;
-    ErtsSysPerfCounter ts;
-    PreFetch(0, next);
-
-    ts = erts_sys_perf_counter();
-
-    if (IS_SSMALL(ts)) {
-        r(0) = make_small((Sint)ts);
-    } else {
-        TestHeap(ERTS_SINT64_HEAP_SIZE(ts),0);
-        r(0) = make_big(HTOP);
-#if defined(ARCH_32)
-        if (ts >= (((Uint64) 1) << 32)) {
-            *HTOP = make_pos_bignum_header(2);
-            BIG_DIGIT(HTOP, 0) = (Uint) (ts & ((Uint) 0xffffffff));
-            BIG_DIGIT(HTOP, 1) = (Uint) ((ts >> 32) & ((Uint) 0xffffffff));
-            HTOP += 3;
-        }
-        else
-#endif
-        {
-                *HTOP = make_pos_bignum_header(1);
-                BIG_DIGIT(HTOP, 0) = (Uint) ts;
-                HTOP += 2;
-        }
-    }
-    NextPF(0, next);
- }
-
- OpCase(i_debug_breakpoint): {
-     HEAVY_SWAPOUT;
-     I = call_error_handler(c_p, erts_code_to_codemfa(I), reg, am_breakpoint);
-     HEAVY_SWAPIN;
-     if (I) {
-	 Goto(*I);
-     }
-     goto handle_error;
- }
-
-
- OpCase(system_limit_j):
- system_limit:
-    c_p->freason = SYSTEM_LIMIT;
-    goto lb_Cl_error;
-
-
 #ifdef ERTS_OPCODE_COUNTER_SUPPORT
     DEFINE_COUNTING_LABELS;
 #endif
@@ -5128,9 +966,6 @@ do {						\
 
  init_emulator:
  {
-     int i;
-     Export* ep;
-
 #ifndef NO_JUMP_TABLE
 #ifdef ERTS_OPCODE_COUNTER_SUPPORT
 #ifdef DEBUG
@@ -5142,35 +977,8 @@ do {						\
      beam_ops = opcodes;
 #endif /* ERTS_OPCODE_COUNTER_SUPPORT */
 #endif /* NO_JUMP_TABLE */
-     
-     em_call_error_handler = OpCode(call_error_handler);
-     em_apply_bif = OpCode(apply_bif);
-     em_call_nif = OpCode(call_nif);
-     em_call_bif_e = OpCode(call_bif_e);
-
-     beam_apply[0]             = (BeamInstr) OpCode(i_apply);
-     beam_apply[1]             = (BeamInstr) OpCode(normal_exit);
-     beam_exit[0]              = (BeamInstr) OpCode(error_action_code);
-     beam_continue_exit[0]     = (BeamInstr) OpCode(continue_exit);
-     beam_return_to_trace[0]   = (BeamInstr) OpCode(i_return_to_trace);
-     beam_return_trace[0]      = (BeamInstr) OpCode(return_trace);
-     beam_exception_trace[0]   = (BeamInstr) OpCode(return_trace); /* UGLY */
-     beam_return_time_trace[0] = (BeamInstr) OpCode(i_return_time_trace);
-
-     /*
-      * Enter all BIFs into the export table.
-      */
-     for (i = 0; i < BIF_SIZE; i++) {
-	 ep = erts_export_put(bif_table[i].module,
-			      bif_table[i].name,
-			      bif_table[i].arity);
-	 bif_export[i] = ep;
-	 ep->beam[0] = (BeamInstr) OpCode(apply_bif);
-	 ep->beam[1] = (BeamInstr) bif_table[i].f;
-	 /* XXX: set func info for bifs */
-	 ep->info.op = (BeamInstr) BeamOp(op_i_func_info_IaaI);
-     }
 
+     init_emulator_finish();
      return;
  }
 #ifdef NO_JUMP_TABLE
@@ -5182,26 +990,71 @@ do {						\
 
   save_calls1:
     {
-	Eterm* dis_next;
+	BeamInstr dis_next;
 
 	save_calls(c_p, (Export *) Arg(0));
 
 	SET_I(((Export *) Arg(0))->addressv[erts_active_code_ix()]);
 
-	dis_next = (Eterm *) *I;
+	dis_next = *I;
 	FCALLS--;
 	Goto(dis_next);
     }
 }
 
 /*
+ * One-time initialization of emulator. Does not need to be
+ * in process_main().
+ */
+static void
+init_emulator_finish(void)
+{
+     int i;
+     Export* ep;
+
+#if defined(ARCH_64) && defined(CODE_MODEL_SMALL)
+     for (i = 0; i < NUMBER_OF_OPCODES; i++) {
+         BeamInstr instr = BeamOpCodeAddr(i);
+         if (instr >= (1ull << 32)) {
+             erts_exit(ERTS_ERROR_EXIT,
+                       "This run-time was supposed be compiled with all code below 2Gb,\n"
+                       "but the instruction '%s' is located at %016lx.\n",
+                       opc[i].name, instr);
+         }
+     }
+#endif
+
+     beam_apply[0]             = BeamOpCodeAddr(op_i_apply);
+     beam_apply[1]             = BeamOpCodeAddr(op_normal_exit);
+     beam_exit[0]              = BeamOpCodeAddr(op_error_action_code);
+     beam_continue_exit[0]     = BeamOpCodeAddr(op_continue_exit);
+     beam_return_to_trace[0]   = BeamOpCodeAddr(op_i_return_to_trace);
+     beam_return_trace[0]      = BeamOpCodeAddr(op_return_trace);
+     beam_exception_trace[0]   = BeamOpCodeAddr(op_return_trace); /* UGLY */
+     beam_return_time_trace[0] = BeamOpCodeAddr(op_i_return_time_trace);
+
+     /*
+      * Enter all BIFs into the export table.
+      */
+     for (i = 0; i < BIF_SIZE; i++) {
+	 ep = erts_export_put(bif_table[i].module,
+			      bif_table[i].name,
+			      bif_table[i].arity);
+	 bif_export[i] = ep;
+	 ep->beam[0] = BeamOpCodeAddr(op_apply_bif);
+	 ep->beam[1] = (BeamInstr) bif_table[i].f;
+	 /* XXX: set func info for bifs */
+	 ep->info.op = BeamOpCodeAddr(op_i_func_info_IaaI);
+     }
+}
+
+/*
  * erts_dirty_process_main() is what dirty schedulers execute. Since they handle
  * only NIF calls they do not need to be able to execute all BEAM
  * instructions.
  */
 void erts_dirty_process_main(ErtsSchedulerData *esdp)
 {
-#ifdef ERTS_DIRTY_SCHEDULERS
     Process* c_p = NULL;
     ErtsMonotonicTime start_time;
 #ifdef DEBUG
@@ -5313,7 +1166,7 @@ void erts_dirty_process_main(ErtsSchedulerData *esdp)
 	}
 
 	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
+	ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
 	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
 	c_p = erts_schedule(esdp, c_p, reds_used);
 
@@ -5327,7 +1180,7 @@ void erts_dirty_process_main(ErtsSchedulerData *esdp)
 #ifdef DEBUG
     pid = c_p->common.id; /* Save for debugging purposes */
 #endif
-    ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
+    ERTS_REQ_PROC_MAIN_LOCK(c_p);
     PROCESS_MAIN_CHK_LOCKS(c_p);
 
     ASSERT(!(c_p->flags & F_HIPE_MODE));
@@ -5342,7 +1195,7 @@ void erts_dirty_process_main(ErtsSchedulerData *esdp)
     else
 	c_p->fcalls = CONTEXT_REDS;
 
-    if (erts_smp_atomic32_read_nob(&c_p->state) & ERTS_PSFLG_DIRTY_RUNNING_SYS) {
+    if (erts_atomic32_read_nob(&c_p->state) & ERTS_PSFLG_DIRTY_RUNNING_SYS) {
 	erts_execute_dirty_system_task(c_p);
 	goto do_dirty_schedule;
     }
@@ -5413,21 +1266,21 @@ void erts_dirty_process_main(ErtsSchedulerData *esdp)
 	c_p->current = codemfa;
 	SWAPOUT;
 	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
+	ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
 
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	if (em_apply_bif == (BeamInstr *) *I) {
+	if (BeamIsOpCode(*I, op_apply_bif)) {
 	    exiting = erts_call_dirty_bif(esdp, c_p, I, reg);
 	}
 	else {
-	    ASSERT(em_call_nif == (BeamInstr *) *I);
-	    exiting = erts_call_dirty_nif(esdp, c_p, I, reg);
+	    ASSERT(BeamIsOpCode(*I, op_call_nif));
+            exiting = erts_call_dirty_nif(esdp, c_p, I, reg);
 	}
 
 	ASSERT(!(c_p->flags & F_HIBERNATE_SCHED));
 
 	PROCESS_MAIN_CHK_LOCKS(c_p);
-	ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
+	ERTS_REQ_PROC_MAIN_LOCK(c_p);
 	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
 	ERTS_MSACC_SET_STATE_CACHED_M_X(ERTS_MSACC_STATE_EMULATOR);
 	if (exiting)
@@ -5440,7 +1293,6 @@ void erts_dirty_process_main(ErtsSchedulerData *esdp)
 	I = c_p->i;
 	goto context_switch;
     }
-#endif /* ERTS_DIRTY_SCHEDULERS */
 }
 
 static ErtsCodeMFA *
@@ -5602,13 +1454,14 @@ handle_error(Process* c_p, BeamInstr* pc, Eterm* reg, ErtsCodeMFA *bif_mfa)
 	reg[3] = c_p->ftrace;
         if ((new_pc = next_catch(c_p, reg))) {
 	    c_p->cp = 0;	/* To avoid keeping stale references. */
+            c_p->msg.saved_last = 0;  /* No longer safe to use this position */
 	    return new_pc;
 	}
 	if (c_p->catches > 0) erts_exit(ERTS_ERROR_EXIT, "Catch not found");
     }
-    ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
+    ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
     terminate_proc(c_p, Value);
-    ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
+    ERTS_REQ_PROC_MAIN_LOCK(c_p);
     return NULL;
 }
 
@@ -6257,8 +2110,8 @@ apply_bif_error_adjustment(Process *p, Export *ep,
      * and apply_last_IP.
      */
     if (I
-	&& ep->beam[0] == (BeamInstr) em_apply_bif
-	&& (ep == bif_export[BIF_error_1]
+	&& BeamIsOpCode(ep->beam[0], op_apply_bif)
+        && (ep == bif_export[BIF_error_1]
 	    || ep == bif_export[BIF_error_2]
 	    || ep == bif_export[BIF_exit_1]
 	    || ep == bif_export[BIF_throw_1])) {
@@ -6344,13 +2197,14 @@ apply_bif_error_adjustment(Process *p, Export *ep,
 }
 
 static BeamInstr*
-apply(
-Process* p, Eterm module, Eterm function, Eterm args, Eterm* reg,
-BeamInstr *I, Uint stack_offset)
+apply(Process* p, Eterm* reg, BeamInstr *I, Uint stack_offset)
 {
     int arity;
     Export* ep;
-    Eterm tmp, this;
+    Eterm tmp;
+    Eterm module = reg[0];
+    Eterm function = reg[1];
+    Eterm args = reg[2];
 
     /*
      * Check the arguments which should be of the form apply(Module,
@@ -6373,20 +2227,8 @@ BeamInstr *I, Uint stack_offset)
 
     while (1) {
 	Eterm m, f, a;
-	/* The module argument may be either an atom or an abstract module
-	 * (currently implemented using tuples, but this might change).
-	 */
-	this = THE_NON_VALUE;
-	if (is_not_atom(module)) {
-	    Eterm* tp;
-
-	    if (is_not_tuple(module)) goto error;
-	    tp = tuple_val(module);
-	    if (arityval(tp[0]) < 1) goto error;
-	    this = module;
-	    module = tp[1];
-	    if (is_not_atom(module)) goto error;
-	}
+
+	if (is_not_atom(module)) goto error;
 
 	if (module != am_erlang || function != am_apply)
 	    break;
@@ -6421,9 +2263,7 @@ BeamInstr *I, Uint stack_offset)
     }
     /*
      * Walk down the 3rd parameter of apply (the argument list) and copy
-     * the parameters to the x registers (reg[]). If the module argument
-     * was an abstract module, add 1 to the function arity and put the
-     * module argument in the n+1st x register as a THIS reference.
+     * the parameters to the x registers (reg[]).
      */
 
     tmp = args;
@@ -6440,9 +2280,6 @@ BeamInstr *I, Uint stack_offset)
     if (is_not_nil(tmp)) {	/* Must be well-formed list */
 	goto error;
     }
-    if (this != THE_NON_VALUE) {
-        reg[arity++] = this;
-    }
 
     /*
      * Get the index into the export table, or failing that the export
@@ -6481,22 +2318,12 @@ fixed_apply(Process* p, Eterm* reg, Uint arity,
 	return 0;
     }
 
-    /* The module argument may be either an atom or an abstract module
-     * (currently implemented using tuples, but this might change).
-     */
-    if (is_not_atom(module)) {
-	Eterm* tp;
-        if (is_not_tuple(module)) goto error;
-        tp = tuple_val(module);
-        if (arityval(tp[0]) < 1) goto error;
-        module = tp[1];
-        if (is_not_atom(module)) goto error;
-        ++arity;
-    }
+    if (is_not_atom(module)) goto error;
 
     /* Handle apply of apply/3... */
-    if (module == am_erlang && function == am_apply && arity == 3)
-	return apply(p, reg[0], reg[1], reg[2], reg, I, stack_offset);
+    if (module == am_erlang && function == am_apply && arity == 3) {
+	return apply(p, reg, I, stack_offset);
+    }
     
     /*
      * Get the index into the export table, or failing that the export
@@ -6517,27 +2344,13 @@ fixed_apply(Process* p, Eterm* reg, Uint arity,
 }
 
 int
-erts_hibernate(Process* c_p, Eterm module, Eterm function, Eterm args, Eterm* reg)
+erts_hibernate(Process* c_p, Eterm* reg)
 {
     int arity;
     Eterm tmp;
-
-#ifndef ERTS_SMP
-    if (ERTS_PROC_IS_EXITING(c_p)) {
-	/*
-	 * I non smp case:
-	 *
-	 * Currently executing process might be sent an exit
-	 * signal if it is traced by a port that it also is
-	 * linked to, and the port terminates during the
-	 * trace. In this case we do *not* want to clear
-	 * the active flag, which will make the process hang
-	 * in limbo forever. Get out of here and terminate
-	 * the process...
-	 */
-	return -1;
-    }
-#endif
+    Eterm module = reg[0];
+    Eterm function = reg[1];
+    Eterm args = reg[2];
 
     if (is_not_atom(module) || is_not_atom(function)) {
 	/*
@@ -6605,33 +2418,22 @@ erts_hibernate(Process* c_p, Eterm module, Eterm function, Eterm args, Eterm* re
      * If there are no waiting messages, garbage collect and
      * shrink the heap. 
      */
-    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
-    ERTS_SMP_MSGQ_MV_INQ2PRIVQ(c_p);
+    erts_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
+    ERTS_MSGQ_MV_INQ2PRIVQ(c_p);
     if (!c_p->msg.len) {
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
 	c_p->fvalue = NIL;
 	PROCESS_MAIN_CHK_LOCKS(c_p);
 	erts_garbage_collect_hibernate(c_p);
 	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
 	PROCESS_MAIN_CHK_LOCKS(c_p);
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
-#ifndef ERTS_SMP
-	if (ERTS_PROC_IS_EXITING(c_p)) {
-	    /*
-	     * See comment in the beginning of the function...
-	     *
-	     * This second test is needed since gc might be traced.
-	     */
-	    return -1;
-	}
-#else /* ERTS_SMP */
-        ERTS_SMP_MSGQ_MV_INQ2PRIVQ(c_p);
+	erts_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
+        ERTS_MSGQ_MV_INQ2PRIVQ(c_p);
 	if (!c_p->msg.len)
-#endif
-	    erts_smp_atomic32_read_band_relb(&c_p->state, ~ERTS_PSFLG_ACTIVE);
+	    erts_atomic32_read_band_relb(&c_p->state, ~ERTS_PSFLG_ACTIVE);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
     }
-    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
+    erts_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
     c_p->current = &bif_export[BIF_hibernate_3]->info.mfa;
     c_p->flags |= F_HIBERNATE_SCHED; /* Needed also when woken! */
     return 1;
@@ -6721,7 +2523,7 @@ call_fun(Process* p,		/* Current process. */
 
 		module = fe->module;
 
-		ERTS_SMP_READ_MEMORY_BARRIER;
+		ERTS_THR_READ_MEMORY_BARRIER;
 		if (fe->pend_purge_address) {
 		    /*
 		     * The system is currently trying to purge the
@@ -6852,7 +2654,7 @@ new_fun(Process* p, Eterm* reg, ErlFunEntry* fe, int num_free)
     p->htop = hp + needed;
     funp = (ErlFunThing *) hp;
     hp = funp->env;
-    erts_smp_refc_inc(&fe->refc, 2);
+    erts_refc_inc(&fe->refc, 2);
     funp->thing_word = HEADER_FUN;
     funp->next = MSO(p).first;
     MSO(p).first = (struct erl_off_heap_header*) funp;
@@ -6955,24 +2757,20 @@ do {						\
 
 
 static Eterm
-new_map(Process* p, Eterm* reg, BeamInstr* I)
+erts_gc_new_map(Process* p, Eterm* reg, Uint live, Uint n, BeamInstr* ptr)
 {
-    Uint n = Arg(3);
     Uint i;
     Uint need = n + 1 /* hdr */ + 1 /*size*/ + 1 /* ptr */ + 1 /* arity */;
     Eterm keys;
     Eterm *mhp,*thp;
     Eterm *E;
-    BeamInstr *ptr;
     flatmap_t *mp;
     ErtsHeapFactory factory;
 
-    ptr = &Arg(4);
-
     if (n > 2*MAP_SMALL_MAP_LIMIT) {
         Eterm res;
 	if (HeapWordsLeft(p) < n) {
-	    erts_garbage_collect(p, n, reg, Arg(2));
+	    erts_garbage_collect(p, n, reg, live);
 	}
 
 	mhp = p->htop;
@@ -6993,7 +2791,7 @@ new_map(Process* p, Eterm* reg, BeamInstr* I)
     }
 
     if (HeapWordsLeft(p) < need) {
-	erts_garbage_collect(p, need, reg, Arg(2));
+	erts_garbage_collect(p, need, reg, live);
     }
 
     thp    = p->htop;
@@ -7016,9 +2814,44 @@ new_map(Process* p, Eterm* reg, BeamInstr* I)
 }
 
 static Eterm
-update_map_assoc(Process* p, Eterm* reg, Eterm map, BeamInstr* I)
+erts_gc_new_small_map_lit(Process* p, Eterm* reg, Eterm keys_literal,
+                          Uint live, BeamInstr* ptr)
+{
+    Eterm* keys = tuple_val(keys_literal);
+    Uint n = arityval(*keys);
+    Uint need = n + 1 /* hdr */ + 1 /*size*/ + 1 /* ptr */ + 1 /* arity */;
+    Uint i;
+    flatmap_t *mp;
+    Eterm *mhp;
+    Eterm *E;
+
+    ASSERT(n <= MAP_SMALL_MAP_LIMIT);
+
+    if (HeapWordsLeft(p) < need) {
+        erts_garbage_collect(p, need, reg, live);
+    }
+
+    mhp = p->htop;
+    E   = p->stop;
+
+    mp = (flatmap_t *)mhp; mhp += MAP_HEADER_FLATMAP_SZ;
+    mp->thing_word = MAP_HEADER_FLATMAP;
+    mp->size = n;
+    mp->keys = keys_literal;
+
+    for (i = 0; i < n; i++) {
+        GET_TERM(*ptr++, *mhp++);
+    }
+
+    p->htop = mhp;
+
+    return make_flatmap(mp);
+}
+
+static Eterm
+erts_gc_update_map_assoc(Process* p, Eterm* reg, Uint live,
+                         Uint n, BeamInstr* new_p)
 {
-    Uint n;
     Uint num_old;
     Uint num_updates;
     Uint need;
@@ -7028,23 +2861,18 @@ update_map_assoc(Process* p, Eterm* reg, Eterm map, BeamInstr* I)
     Eterm* E;
     Eterm* old_keys;
     Eterm* old_vals;
-    BeamInstr* new_p;
     Eterm new_key;
     Eterm* kp;
+    Eterm map;
 
-    new_p = &Arg(5);
-    num_updates = Arg(4) / 2;
+    num_updates = n / 2;
+    map = reg[live];
 
     if (is_not_flatmap(map)) {
 	Uint32 hx;
 	Eterm val;
 
-	/* apparently the compiler does not emit is_map instructions,
-	 * bad compiler */
-
-	if (is_not_hashmap(map))
-	    return THE_NON_VALUE;
-
+	ASSERT(is_hashmap(map));
 	res = map;
 	E = p->stop;
 	while(num_updates--) {
@@ -7068,7 +2896,7 @@ update_map_assoc(Process* p, Eterm* reg, Eterm map, BeamInstr* I)
      */
 
     if (num_old == 0) {
-	return new_map(p, reg, I+1);
+	return erts_gc_new_map(p, reg, live, n, new_p);
     }
 
     /*
@@ -7078,8 +2906,6 @@ update_map_assoc(Process* p, Eterm* reg, Eterm map, BeamInstr* I)
 
     need = 2*(num_old+num_updates) + 1 + MAP_HEADER_FLATMAP_SZ;
     if (HeapWordsLeft(p) < need) {
-	Uint live = Arg(3);
-	reg[live] = map;
 	erts_garbage_collect(p, need, reg, live+1);
 	map      = reg[live];
 	old_mp   = (flatmap_t *)flatmap_val(map);
@@ -7226,9 +3052,8 @@ update_map_assoc(Process* p, Eterm* reg, Eterm map, BeamInstr* I)
  */
 
 static Eterm
-update_map_exact(Process* p, Eterm* reg, Eterm map, BeamInstr* I)
+erts_gc_update_map_exact(Process* p, Eterm* reg, Uint live, Uint n, Eterm* new_p)
 {
-    Uint n;
     Uint i;
     Uint num_old;
     Uint need;
@@ -7238,12 +3063,12 @@ update_map_exact(Process* p, Eterm* reg, Eterm map, BeamInstr* I)
     Eterm* E;
     Eterm* old_keys;
     Eterm* old_vals;
-    BeamInstr* new_p;
     Eterm new_key;
+    Eterm map;
 
-    new_p = &Arg(5);
-    n = Arg(4) / 2;		/* Number of values to be updated */
+    n /= 2;		/* Number of values to be updated */
     ASSERT(n > 0);
+    map = reg[live];
 
     if (is_not_flatmap(map)) {
 	Uint32 hx;
@@ -7297,8 +3122,6 @@ update_map_exact(Process* p, Eterm* reg, Eterm map, BeamInstr* I)
 
     need = num_old + MAP_HEADER_FLATMAP_SZ;
     if (HeapWordsLeft(p) < need) {
-	Uint live = Arg(3);
-	reg[live] = map;
 	erts_garbage_collect(p, need, reg, live+1);
 	map      = reg[live];
 	old_mp   = (flatmap_t *)flatmap_val(map);
@@ -7380,13 +3203,16 @@ erts_is_builtin(Eterm Mod, Eterm Name, int arity)
     Export e;
     Export* ep;
 
-    if (Mod == am_erlang && Name == am_apply && arity == 3) {
-	/*
-	 * Special case. apply/3 is built-in (implemented in C),
-	 * but implemented in a different way than all other
-	 * BIFs.
-	 */
-	return 1;
+    if (Mod == am_erlang) {
+        /*
+         * Special case for built-in functions that are implemented
+         * as instructions as opposed to SNIFs.
+         */
+        if (Name == am_apply && (arity == 2 || arity == 3)) {
+            return 1;
+        } else if (Name == am_yield && arity == 0) {
+            return 1;
+        }
     }
 
     e.info.mfa.module = Mod;
@@ -7396,8 +3222,8 @@ erts_is_builtin(Eterm Mod, Eterm Name, int arity)
     if ((ep = export_get(&e)) == NULL) {
 	return 0;
     }
-    return ep->addressv[erts_active_code_ix()] == ep->beam
-	&& (ep->beam[0] == (BeamInstr) em_apply_bif);
+    return ep->addressv[erts_active_code_ix()] == ep->beam &&
+	BeamIsOpCode(ep->beam[0], op_apply_bif);
 }
 
 
diff --git a/erts/emulator/beam/beam_load.c b/erts/emulator/beam/beam_load.c
index adf8779f11..e43f7fda2c 100644
--- a/erts/emulator/beam/beam_load.c
+++ b/erts/emulator/beam/beam_load.c
@@ -55,12 +55,6 @@ ErlDrvBinary* erts_gzinflate_buffer(char*, int);
 #define DEFINED   1
 #define EXPORTED  2
 
-#ifdef NO_JUMP_TABLE
-#  define BeamOpCode(Op) ((BeamInstr)(Op))
-#else
-#  define BeamOpCode(Op) ((BeamInstr)beam_ops[Op])
-#endif
-
 #if defined(WORDS_BIGENDIAN)
 # define NATIVE_ENDIAN(F)			\
   if ((F).val & BSF_NATIVE) {			\
@@ -81,16 +75,28 @@ ErlDrvBinary* erts_gzinflate_buffer(char*, int);
 #define TE_FAIL (-1)
 #define TE_SHORT_WINDOW (-2)
 
+/*
+ * Type for a reference to a label that must be patched.
+ */
+
 typedef struct {
-    Uint value;			/* Value of label (NULL if not known yet). */
-    Sint patches;		/* Index (into code buffer) to first location
-				 * which must be patched with the value of this label.
-				 */
-#ifdef ERTS_SMP
+    Uint pos;                   /* Position of label reference to patch. */
+    Uint offset;                /* Offset from patch location.  */
+    int packed;                 /* 0 (not packed), 1 (lsw), 2 (msw) */
+} LabelPatch;
+
+/*
+ * Type for a label.
+ */
+
+typedef struct {
+    Uint value;			/* Value of label (0 if not known yet). */
     Uint looprec_targeted;	/* Non-zero if this label is the target of a loop_rec
 				 * instruction.
 				 */
-#endif
+    LabelPatch* patches;       /* Array of label patches. */
+    Uint num_patches;           /* Number of patches in array. */
+    Uint num_allocated;         /* Number of allocated patches. */
 } Label;
 
 /*
@@ -227,7 +233,7 @@ typedef struct {
 
 typedef struct literal_patch LiteralPatch;
 struct literal_patch {
-    int pos;			/* Position in code */
+    Uint pos;			/* Position in code */
     LiteralPatch* next;
 };
 
@@ -307,6 +313,7 @@ typedef struct LoaderState {
     int on_load;		/* Index in the code for the on_load function
 				 * (or 0 if there is no on_load function)
 				 */
+    int otp_20_or_higher;       /* Compiled with OTP 20 or higher */
 
     /*
      * Atom table.
@@ -507,6 +514,7 @@ static int read_lambda_table(LoaderState* stp);
 static int read_literal_table(LoaderState* stp);
 static int read_line_table(LoaderState* stp);
 static int read_code_header(LoaderState* stp);
+static void init_label(Label* lp);
 static int load_code(LoaderState* stp);
 static GenOp* gen_element(LoaderState* stp, GenOpArg Fail, GenOpArg Index,
 			  GenOpArg Tuple, GenOpArg Dst);
@@ -537,6 +545,7 @@ static int get_tag_and_value(LoaderState* stp, Uint len_code,
 static int new_label(LoaderState* stp);
 static void new_literal_patch(LoaderState* stp, int pos);
 static void new_string_patch(LoaderState* stp, int pos);
+static int find_literal(LoaderState* stp, Eterm needle, Uint *idx);
 static Uint new_literal(LoaderState* stp, Eterm** hpp, Uint heap_size);
 static int genopargcompare(GenOpArg* a, GenOpArg* b);
 static Eterm get_module_info(Process* p, ErtsCodeIndex code_ix,
@@ -740,6 +749,13 @@ erts_prepare_loading(Binary* magic, Process *c_p, Eterm group_leader,
     }
 
     /*
+     * Find out whether the code was compiled with OTP 20
+     * or higher.
+     */
+
+    stp->otp_20_or_higher = stp->chunks[UTF8_ATOM_CHUNK].size > 0;
+
+    /*
      * Load the code chunk.
      */
 
@@ -790,13 +806,8 @@ erts_finish_loading(Binary* magic, Process* c_p,
     struct erl_module_instance* inst_p;
     Uint size;
 
-    /*
-     * No other process may run since we will update the export
-     * table which is not protected by any locks.
-     */
-
-    ERTS_SMP_LC_ASSERT(erts_initialized == 0 || erts_has_code_write_permission() ||
-		       erts_smp_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(erts_initialized == 0 || erts_has_code_write_permission() ||
+		       erts_thr_progress_is_blocking());
     /*
      * Make current code for the module old and insert the new code
      * as current.  This will fail if there already exists old code
@@ -827,11 +838,10 @@ erts_finish_loading(Binary* magic, Process* c_p,
 		continue;
 	    }
 	    if (ep->addressv[code_ix] == ep->beam) {
-		if (ep->beam[0] == (BeamInstr) em_apply_bif) {
+		if (BeamIsOpCode(ep->beam[0], op_apply_bif)) {
 		    continue;
-		} else if (ep->beam[0] ==
-			   (BeamInstr) BeamOp(op_i_generic_breakpoint)) {
-		    ERTS_SMP_LC_ASSERT(erts_smp_thr_progress_is_blocking());
+		} else if (BeamIsOpCode(ep->beam[0], op_i_generic_breakpoint)) {
+		    ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
 		    ASSERT(mod_tab_p->curr.num_traced_exports > 0);
 		    erts_clear_export_break(mod_tab_p, &ep->info);
 		    ep->addressv[code_ix] = (BeamInstr *) ep->beam[1];
@@ -1043,6 +1053,10 @@ loader_state_dtor(Binary* magic)
         stp->codev = 0;
     }
     if (stp->labels != 0) {
+        Uint num;
+        for (num = 0; num < stp->num_labels; num++) {
+            erts_free(ERTS_ALC_T_PREPARED_CODE, (void *) stp->labels[num].patches);
+        }
 	erts_free(ERTS_ALC_T_PREPARED_CODE, (void *) stp->labels);
 	stp->labels = 0;
     }
@@ -1456,7 +1470,7 @@ load_import_table(LoaderState* stp)
 	 * the BIF function.
 	 */
 	if ((e = erts_active_export_entry(mod, func, arity)) != NULL) {
-	    if (e->beam[0] == (BeamInstr) em_apply_bif) {
+	    if (BeamIsOpCode(e->beam[0], op_apply_bif)) {
 		stp->import[i].bf = (BifFunction) e->beam[1];
 		if (func == am_load_nif && mod == am_erlang && arity == 2) {
 		    stp->may_load_nif = 1;
@@ -1526,7 +1540,7 @@ read_export_table(LoaderState* stp)
 	 * any other functions that walk through all local functions.
 	 */
 
-	if (stp->labels[n].patches >= 0) {
+	if (stp->labels[n].num_patches > 0) {
 	    LoadError3(stp, "there are local calls to the stub for "
 		       "the BIF %T:%T/%d",
 		       stp->module, func, arity);
@@ -1550,7 +1564,7 @@ is_bif(Eterm mod, Eterm func, unsigned arity)
     if (e == NULL) {
 	return 0;
     }
-    if (e->beam[0] != (BeamInstr) em_apply_bif) {
+    if (! BeamIsOpCode(e->beam[0], op_apply_bif)) {
 	return 0;
     }
     if (mod == am_erlang && func == am_apply && arity == 3) {
@@ -1872,11 +1886,7 @@ read_code_header(LoaderState* stp)
     stp->labels = (Label *) erts_alloc(ERTS_ALC_T_PREPARED_CODE,
 				       stp->num_labels * sizeof(Label));
     for (i = 0; i < stp->num_labels; i++) {
-	stp->labels[i].value = 0;
-	stp->labels[i].patches = -1;
-#ifdef ERTS_SMP
-	stp->labels[i].looprec_targeted = 0;
-#endif
+        init_label(&stp->labels[i]);
     }
 
     stp->catches = 0;
@@ -1905,12 +1915,43 @@ read_code_header(LoaderState* stp)
     
 #define TermWords(t) (((t) / (sizeof(BeamInstr)/sizeof(Eterm))) + !!((t) % (sizeof(BeamInstr)/sizeof(Eterm))))
 
+static void init_label(Label* lp)
+{
+    lp->value = 0;
+    lp->looprec_targeted = 0;
+    lp->num_patches = 0;
+    lp->num_allocated = 4;
+    lp->patches = erts_alloc(ERTS_ALC_T_PREPARED_CODE,
+                             lp->num_allocated * sizeof(LabelPatch));
+}
+
+static void
+register_label_patch(LoaderState* stp, Uint label, Uint ci, Uint offset)
+{
+    Label* lp;
+
+    ASSERT(label < stp->num_labels);
+    lp = &stp->labels[label];
+    if (lp->num_allocated <= lp->num_patches) {
+        lp->num_allocated *= 2;
+        lp->patches = erts_realloc(ERTS_ALC_T_PREPARED_CODE,
+                                   (void *) lp->patches,
+                                   lp->num_allocated * sizeof(LabelPatch));
+    }
+    lp->patches[lp->num_patches].pos = ci;
+    lp->patches[lp->num_patches].offset = offset;
+    lp->patches[lp->num_patches].packed = 0;
+    lp->num_patches++;
+    stp->codev[ci] = label;
+}
+
 static int
 load_code(LoaderState* stp)
 {
     int i;
-    int ci;
-    int last_func_start = 0;	/* Needed by nif loading and line instructions */
+    Uint ci;
+    Uint last_instr_start;       /* Needed for relative jumps */
+    Uint last_func_start = 0;	/* Needed by nif loading and line instructions */
     char* sign;
     int arg;			/* Number of current argument. */
     int num_specific;		/* Number of specific ops for current. */
@@ -1923,6 +1964,9 @@ load_code(LoaderState* stp)
     GenOp** last_op_next = NULL;
     int arity;
     int retval = 1;
+#if defined(BEAM_WIDE_SHIFT)
+    int num_trailing_f;     /* Number of extra 'f' arguments in a list */
+#endif
 
     /*
      * The size of the loaded func_info instruction is needed
@@ -2028,30 +2072,10 @@ load_code(LoaderState* stp)
 		    case 0:
 			/* Floating point number.
 			 * Not generated by the compiler in R16B and later.
+                         * (The literal pool is used instead.)
 			 */
-			{
-			    Eterm* hp;
-#if !defined(ARCH_64)
-			    Uint high, low;
-# endif
-			    last_op->a[arg].val = new_literal(stp, &hp,
-							      FLOAT_SIZE_OBJECT);
-			    hp[0] = HEADER_FLONUM;
-			    last_op->a[arg].type = TAG_q;
-#if defined(ARCH_64)
-			    GetInt(stp, 8, hp[1]);
-# else
-			    GetInt(stp, 4, high);
-			    GetInt(stp, 4, low);
-			    if (must_swap_floats) {
-				Uint t = high;
-				high = low;
-				low = t;
-			    }
-			    hp[1] = high;
-			    hp[2] = low;
-# endif
-			}
+                        LoadError0(stp, "please re-compile this module with an "
+                                   ERLANG_OTP_RELEASE " compiler");
 			break;
 		    case 1:	/* List. */
 			if (arg+1 != arity) {
@@ -2286,7 +2310,8 @@ load_code(LoaderState* stp)
 
 	    stp->specific_op = specific;
 	    CodeNeed(opc[stp->specific_op].sz+16); /* Extra margin for packing */
-	    code[ci++] = BeamOpCode(stp->specific_op);
+            last_instr_start = ci + opc[stp->specific_op].adjust;
+	    code[ci++] = BeamOpCodeAddr(stp->specific_op);
 	}
 	
 	/*
@@ -2359,8 +2384,18 @@ load_code(LoaderState* stp)
 		    code[ci++] = NIL;
 		    break;
 		case TAG_q:
-		    new_literal_patch(stp, ci);
-		    code[ci++] = tmp_op->a[arg].val;
+                    {
+                        BeamInstr val = tmp_op->a[arg].val;
+                        Eterm term = stp->literals[val].term;
+                        new_literal_patch(stp, ci);
+                        code[ci++] = val;
+                        switch (loader_tag(term)) {
+                        case LOADER_X_REG:
+                        case LOADER_Y_REG:
+                            LoadError1(stp, "the term '%T' would be confused "
+                                       "with a register", term);
+                        }
+                    }
 		    break;
 		default:
 		    LoadError1(stp, "bad tag %d for general source",
@@ -2368,7 +2403,8 @@ load_code(LoaderState* stp)
 		    break;
 		}
 		break;
-	    case 'd':	/* Destination (x(0), x(N), y(N) */
+	    case 'd':	/* Destination (x(N), y(N) */
+            case 'S':   /* Source (x(N), y(N)) */
 		switch (tag) {
 		case TAG_x:
 		    code[ci++] = tmp_op->a[arg].val * sizeof(Eterm);
@@ -2382,11 +2418,29 @@ load_code(LoaderState* stp)
 		    break;
 		}
 		break;
-	    case 'I':	/* Untagged integer (or pointer). */
-		VerifyTag(stp, tag, TAG_u);
-		code[ci++] = tmp_op->a[arg].val;
-		break;
-	    case 't':	/* Small untagged integer -- can be packed. */
+	    case 't':	/* Small untagged integer (16 bits) -- can be packed. */
+	    case 'I':	/* Untagged integer (32 bits) -- can be packed.  */
+	    case 'W':	/* Untagged integer or pointer (machine word). */
+#ifdef DEBUG
+                switch (*sign) {
+                case 't':
+                    if (tmp_op->a[arg].val >> 16 != 0) {
+                        load_printf(__LINE__, stp, "value %lu of type 't' does not fit in 16 bits",
+                                    tmp_op->a[arg].val);
+                        ASSERT(0);
+                    }
+                    break;
+#ifdef ARCH_64
+                case 'I':
+                    if (tmp_op->a[arg].val >> 32 != 0) {
+                        load_printf(__LINE__, stp, "value %lu of type 'I' does not fit in 32 bits",
+                                    tmp_op->a[arg].val);
+                        ASSERT(0);
+                    }
+                    break;
+#endif
+                }
+#endif
 		VerifyTag(stp, tag, TAG_u);
 		code[ci++] = tmp_op->a[arg].val;
 		break;
@@ -2396,16 +2450,14 @@ load_code(LoaderState* stp)
 		break;
 	    case 'f':		/* Destination label */
 		VerifyTag(stp, tag_to_letter[tag], *sign);
-		code[ci] = stp->labels[tmp_op->a[arg].val].patches;
-		stp->labels[tmp_op->a[arg].val].patches = ci;
+                register_label_patch(stp, tmp_op->a[arg].val, ci, -last_instr_start);
 		ci++;
 		break;
 	    case 'j':		/* 'f' or 'p' */
 		if (tag == TAG_p) {
 		    code[ci] = 0;
 		} else if (tag == TAG_f) {
-		    code[ci] = stp->labels[tmp_op->a[arg].val].patches;
-		    stp->labels[tmp_op->a[arg].val].patches = ci;
+                    register_label_patch(stp, tmp_op->a[arg].val, ci, -last_instr_start);
 		} else {
 		    LoadError3(stp, "bad tag %d; expected %d or %d",
 			       tag, TAG_f, TAG_p);
@@ -2425,7 +2477,6 @@ load_code(LoaderState* stp)
 		    LoadError1(stp, "label %d defined more than once", last_label);
 		}
 		stp->labels[last_label].value = ci;
-		ASSERT(stp->labels[last_label].patches < ci);
 		break;
 	    case 'e':		/* Export entry */
 		VerifyTag(stp, tag, TAG_u);
@@ -2471,39 +2522,168 @@ load_code(LoaderState* stp)
 	 * The packing engine.
 	 */
 	if (opc[stp->specific_op].pack[0]) {
-	    char* prog;		/* Program for packing engine. */
-	    BeamInstr stack[8];	/* Stack. */
-	    BeamInstr* sp = stack;	/* Points to next free position. */
-	    BeamInstr packed = 0;	/* Accumulator for packed operations. */
+	    char* prog;            /* Program for packing engine. */
+	    struct pack_stack {
+                BeamInstr instr;
+                Uint* patch_pos;
+            } stack[8];            /* Stack. */
+	    struct pack_stack* sp = stack; /* Points to next free position. */
+	    BeamInstr packed = 0; /* Accumulator for packed operations. */
+            LabelPatch* packed_label = 0;
 
 	    for (prog = opc[stp->specific_op].pack; *prog; prog++) {
 		switch (*prog) {
-		case 'g':	/* Get instruction; push on stack. */
-		    *sp++ = code[--ci];
-		    break;
-		case 'i':	/* Initialize packing accumulator. */
-		    packed = code[--ci];
+		case 'g':	/* Get operand and push on stack. */
+                    ci--;
+                    sp->instr = code[ci];
+                    sp->patch_pos = 0;
+                    sp++;
+                    break;
+		case 'f':	/* Get possible 'f' operand and push on stack. */
+                    {
+                        Uint w = code[--ci];
+                        sp->instr = w;
+                        sp->patch_pos = 0;
+
+                        if (w != 0) {
+                            LabelPatch* lbl_p;
+                            int num_patches;
+                            int patch;
+
+                            ASSERT(w < stp->num_labels);
+                            lbl_p = stp->labels[w].patches;
+                            num_patches = stp->labels[w].num_patches;
+                            for (patch = num_patches - 1; patch >= 0; patch--) {
+                                if (lbl_p[patch].pos == ci) {
+                                    sp->patch_pos = &lbl_p[patch].pos;
+                                    break;
+                                }
+                            }
+                            ASSERT(sp->patch_pos);
+                        }
+                        sp++;
+                    }
+                    break;
+		case 'q':	/* Get possible 'q' operand and push on stack. */
+                    {
+                        LiteralPatch* lp;
+
+                        ci--;
+                        sp->instr = code[ci];
+                        sp->patch_pos = 0;
+
+                        for (lp = stp->literal_patches;
+                             lp && lp->pos > ci-MAX_OPARGS;
+                             lp = lp->next) {
+                            if (lp->pos == ci) {
+                                sp->patch_pos = &lp->pos;
+                                break;
+                            }
+                        }
+                        sp++;
+                    }
+                    break;
+#ifdef ARCH_64
+		case '1':	/* Tightest shift (always 10 bits) */
+                    ci--;
+                    ASSERT((code[ci] & ~0x1FF8ull) == 0); /* Fits in 10 bits */
+                    packed = (packed << BEAM_TIGHTEST_SHIFT);
+                    packed |= code[ci] >> 3;
+                    if (packed_label) {
+                        packed_label->packed++;
+                    }
 		    break;
-		case '0':	/* Tight shift */
+#endif
+		case '2':	/* Tight shift (10 or 16 bits) */
 		    packed = (packed << BEAM_TIGHT_SHIFT) | code[--ci];
+                    if (packed_label) {
+                        packed_label->packed++;
+                    }
 		    break;
-		case '6':	/* Shift 16 steps */
+		case '3':	/* Loose shift (16 bits) */
 		    packed = (packed << BEAM_LOOSE_SHIFT) | code[--ci];
+                    if (packed_label) {
+                        packed_label->packed++;
+                    }
 		    break;
 #ifdef ARCH_64
-		case 'w':	/* Shift 32 steps */
-		    packed = (packed << BEAM_WIDE_SHIFT) | code[--ci];
-		    break;
+		case '4':	/* Wide shift (32 bits) */
+                    {
+                        Uint w = code[--ci];
+
+                        if (packed_label) {
+                            packed_label->packed++;
+                        }
+
+                        /*
+                         * 'w' can handle both labels ('f' and 'j'), as well
+                         * as 'I'. Test whether this is a label.
+                         */
+
+                        if (w < stp->num_labels) {
+                            /*
+                             * Probably a label. Look for patch pointing to this
+                             * position.
+                             */
+                            LabelPatch* lp = stp->labels[w].patches;
+                            int num_patches = stp->labels[w].num_patches;
+                            int patch;
+                            for (patch = num_patches - 1; patch >= 0; patch--) {
+                                if (lp[patch].pos == ci) {
+                                    lp[patch].packed = 1;
+                                    packed_label = &lp[patch];
+                                    break;
+                                }
+                            }
+                        }
+                        packed = (packed << BEAM_WIDE_SHIFT) |
+                            (code[ci] & BEAM_WIDE_MASK);
+                    }
+                    break;
 #endif
 		case 'p':	/* Put instruction (from stack). */
-		    code[ci++] = *--sp;
+                    --sp;
+                    code[ci] = sp->instr;
+                    if (sp->patch_pos) {
+                        *sp->patch_pos = ci;
+                    }
+                    ci++;
 		    break;
-		case 'P':	/* Put packed operands. */
-		    *sp++ = packed;
+		case 'P':	/* Put packed operands (on the stack). */
+                    sp->instr = packed;
+                    sp->patch_pos = 0;
+                    if (packed_label) {
+                        sp->patch_pos = &packed_label->pos;
+                        packed_label = 0;
+                    }
+                    sp++;
 		    packed = 0;
 		    break;
+#if defined(ARCH_64) && defined(CODE_MODEL_SMALL)
+                case '#':       /* -1 */
+                case '$':       /* -2 */
+                case '%':       /* -3 */
+                case '&':       /* -4 */
+                case '\'':      /* -5 */
+                case '(':       /* -6 */
+                    /* Pack accumulator contents into instruction word. */
+                    {
+                        Sint pos = ci - (*prog - '#' + 1);
+                        /* Are the high 32 bits of the instruction word zero? */
+                        ASSERT((code[pos] & ~((1ull << BEAM_WIDE_SHIFT)-1)) == 0);
+                        code[pos] |= packed << BEAM_WIDE_SHIFT;
+                        if (packed_label) {
+                            ASSERT(packed_label->packed == 1);
+                            packed_label->pos = pos;
+                            packed_label->packed = 2;
+                            packed_label = 0;
+                        }
+                        packed >>= BEAM_WIDE_SHIFT;
+                    }
+		    break;
+#endif
 		default:
-		    ASSERT(0);
+                    erts_exit(ERTS_ERROR_EXIT, "beam_load: invalid packing op: %c\n", *prog);
 		}
 	    }
 	    ASSERT(sp == stack); /* Incorrect program? */
@@ -2513,7 +2693,17 @@ load_code(LoaderState* stp)
 	 * Load any list arguments using the primitive tags.
 	 */
 
+#if defined(BEAM_WIDE_SHIFT)
+        num_trailing_f = 0;
+#endif
 	for ( ; arg < tmp_op->arity; arg++) {
+#if defined(BEAM_WIDE_SHIFT)
+	    if (tmp_op->a[arg].type == TAG_f) {
+                num_trailing_f++;
+            } else {
+                num_trailing_f = 0;
+            }
+#endif
 	    switch (tmp_op->a[arg].type) {
 	    case TAG_i:
 		CodeNeed(1);
@@ -2527,8 +2717,7 @@ load_code(LoaderState* stp)
 		break;
 	    case TAG_f:
 		CodeNeed(1);
-		code[ci] = stp->labels[tmp_op->a[arg].val].patches;
-		stp->labels[tmp_op->a[arg].val].patches = ci;
+                register_label_patch(stp, tmp_op->a[arg].val, ci, -last_instr_start);
 		ci++;
 		break;
 	    case TAG_x:
@@ -2554,6 +2743,61 @@ load_code(LoaderState* stp)
 	    }
 	}
 
+        /*
+         * If all the extra arguments were 'f' operands,
+         * and the wordsize is 64 bits, pack two 'f' operands
+         * into each word.
+         */
+
+#if defined(BEAM_WIDE_SHIFT)
+        if (num_trailing_f >= 1) {
+            Uint src_index = ci - num_trailing_f;
+            Uint src_limit = ci;
+            Uint dst_limit = src_index + (num_trailing_f+1)/2;
+
+            ci = src_index;
+            while (ci < dst_limit) {
+                Uint w[2];
+                BeamInstr packed = 0;
+                int wi;
+
+                w[0] = code[src_index];
+                if (src_index+1 < src_limit) {
+                    w[1] = code[src_index+1];
+                } else {
+                    w[1] = 0;
+                }
+                for (wi = 0; wi < 2; wi++) {
+                    Uint lbl = w[wi];
+                    LabelPatch* lp = stp->labels[lbl].patches;
+                    int num_patches = stp->labels[lbl].num_patches;
+
+#if defined(WORDS_BIGENDIAN)
+                    packed <<= BEAM_WIDE_SHIFT;
+                    packed |= lbl & BEAM_WIDE_MASK;
+#else
+                    packed >>= BEAM_WIDE_SHIFT;
+                    packed |= lbl << BEAM_WIDE_SHIFT;
+#endif
+                    while (num_patches-- > 0) {
+                        if (lp->pos == src_index + wi) {
+                            lp->pos = ci;
+#if defined(WORDS_BIGENDIAN)
+                            lp->packed = 2 - wi;
+#else
+                            lp->packed = wi + 1;
+#endif
+                            break;
+                        }
+                        lp++;
+                    }
+                }
+                code[ci++] = packed;
+                src_index += 2;
+            }
+        }
+#endif
+
 	/*
 	 * Handle a few special cases.
 	 */
@@ -2600,17 +2844,16 @@ load_code(LoaderState* stp)
                    the size of the ops.tab i_func_info instruction is not
                    the same as FUNC_INFO_SZ */
 		ASSERT(stp->labels[last_label].value == ci - FUNC_INFO_SZ);
-		stp->hdr->functions[function_number] = (ErtsCodeInfo*) stp->labels[last_label].patches;
 		offset = function_number;
-		stp->labels[last_label].patches = offset;
+                register_label_patch(stp, last_label, offset, 0);
 		function_number++;
 		if (stp->arity > MAX_ARG) {
 		    LoadError1(stp, "too many arguments: %d", stp->arity);
 		}
 #ifdef DEBUG
-		ASSERT(stp->labels[0].patches < 0); /* Should not be referenced. */
+		ASSERT(stp->labels[0].num_patches == 0); /* Should not be referenced. */
 		for (i = 1; i < stp->num_labels; i++) {
-		    ASSERT(stp->labels[i].patches < ci);
+                    ASSERT(stp->labels[i].num_patches <= stp->labels[i].num_allocated);
 		}
 #endif
 	    }
@@ -2621,8 +2864,8 @@ load_code(LoaderState* stp)
 	    /* Remember offset for the on_load function. */
 	    stp->on_load = ci;
 	    break;
-	case op_bs_put_string_II:
-	case op_i_bs_match_string_xfII:
+	case op_bs_put_string_WW:
+	case op_i_bs_match_string_xfWW:
 	    new_string_patch(stp, ci-1);
 	    break;
 
@@ -2733,6 +2976,12 @@ load_code(LoaderState* stp)
 
 #define never(St) 0
 
+static int
+compiled_with_otp_20_or_higher(LoaderState* stp)
+{
+    return stp->otp_20_or_higher;
+}
+
 /*
  * Predicate that tests whether a jump table can be used.
  */
@@ -2872,17 +3121,18 @@ gen_element(LoaderState* stp, GenOpArg Fail, GenOpArg Index,
     op->next = NULL;
 
     if (Index.type == TAG_i && Index.val > 0 &&
+        Index.val <= ERTS_MAX_TUPLE_SIZE &&
 	(Tuple.type == TAG_x || Tuple.type == TAG_y)) {
 	op->op = genop_i_fast_element_4;
-	op->a[0] = Fail;
-	op->a[1] = Tuple;
+	op->a[0] = Tuple;
+	op->a[1] = Fail;
 	op->a[2].type = TAG_u;
 	op->a[2].val = Index.val;
 	op->a[3] = Dst;
     } else {
 	op->op = genop_i_element_4;
-	op->a[0] = Fail;
-	op->a[1] = Tuple;
+	op->a[0] = Tuple;
+	op->a[1] = Fail;
 	op->a[2] = Index;
 	op->a[3] = Dst;
     }
@@ -2962,13 +3212,14 @@ gen_get_integer2(LoaderState* stp, GenOpArg Fail, GenOpArg Ms, GenOpArg Live,
 	    op->a[0] = Ms;
 	    op->a[1] = Fail;
 	    op->a[2] = Dst;
+#ifdef ARCH_64
 	} else if (bits == 32 && (Flags.val & BSF_LITTLE) == 0) {
-	    op->op = genop_i_bs_get_integer_32_4;
-	    op->arity = 4;
+	    op->op = genop_i_bs_get_integer_32_3;
+	    op->arity = 3;
 	    op->a[0] = Ms;
 	    op->a[1] = Fail;
-	    op->a[2] = Live;
-	    op->a[3] = Dst;
+	    op->a[2] = Dst;
+#endif
 	} else {
 	generic:
 	    if (bits < SMALL_BITS) {
@@ -3103,16 +3354,6 @@ gen_get_binary2(LoaderState* stp, GenOpArg Fail, GenOpArg Ms, GenOpArg Live,
 }
 
 /*
- * Predicate to test whether a heap binary should be generated.
- */
-
-static int
-should_gen_heap_bin(LoaderState* stp, GenOpArg Src)
-{
-    return Src.val <= ERL_ONHEAP_BIN_LIMIT;
-}
-
-/*
  * Predicate to test whether a binary construction is too big.
  */
 
@@ -3384,27 +3625,14 @@ negation_is_small(LoaderState* stp, GenOpArg Int)
            IS_SSMALL(-((Sint)Int.val));
 }
 
-
-static int
-smp(LoaderState* stp)
-{
-#ifdef ERTS_SMP
-    return 1;
-#else
-    return 0;
-#endif
-}
-
 /*
  * Mark this label.
  */
 static int
 smp_mark_target_label(LoaderState* stp, GenOpArg L)
 {
-#ifdef ERTS_SMP
     ASSERT(L.type == TAG_f);
     stp->labels[L.val].looprec_targeted = 1;
-#endif
     return 1;
 }
 
@@ -3415,12 +3643,8 @@ smp_mark_target_label(LoaderState* stp, GenOpArg L)
 static int
 smp_already_locked(LoaderState* stp, GenOpArg L)
 {
-#ifdef ERTS_SMP
     ASSERT(L.type == TAG_u);
     return stp->labels[L.val].looprec_targeted;
-#else
-    return 0;
-#endif
 }
 
 /*
@@ -3434,11 +3658,11 @@ gen_literal_timeout(LoaderState* stp, GenOpArg Fail, GenOpArg Time)
     Sint timeout;
 
     NEW_GENOP(stp, op);
-    op->op = genop_i_wait_timeout_2;
+    op->op = genop_wait_timeout_unlocked_int_2;
     op->next = NULL;
     op->arity = 2;
-    op->a[0] = Fail;
-    op->a[1].type = TAG_u;
+    op->a[0].type = TAG_u;
+    op->a[1] = Fail;
     
     if (Time.type == TAG_i && (timeout = Time.val) >= 0 &&
 #if defined(ARCH_64)
@@ -3447,7 +3671,7 @@ gen_literal_timeout(LoaderState* stp, GenOpArg Fail, GenOpArg Time)
 	1
 #endif
 	) {
-	op->a[1].val = timeout;
+	op->a[0].val = timeout;
 #if !defined(ARCH_64)
     } else if (Time.type == TAG_q) {
 	Eterm big;
@@ -3461,7 +3685,7 @@ gen_literal_timeout(LoaderState* stp, GenOpArg Fail, GenOpArg Time)
 	} else {
 	    Uint u;
 	    (void) term_to_Uint(big, &u);
-	    op->a[1].val = (BeamInstr) u;
+	    op->a[0].val = (BeamInstr) u;
 	}
 #endif
     } else {
@@ -3481,12 +3705,12 @@ gen_literal_timeout_locked(LoaderState* stp, GenOpArg Fail, GenOpArg Time)
     Sint timeout;
 
     NEW_GENOP(stp, op);
-    op->op = genop_i_wait_timeout_locked_2;
+    op->op = genop_wait_timeout_locked_int_2;
     op->next = NULL;
     op->arity = 2;
-    op->a[0] = Fail;
-    op->a[1].type = TAG_u;
-    
+    op->a[0].type = TAG_u;
+    op->a[1] = Fail;
+
     if (Time.type == TAG_i && (timeout = Time.val) >= 0 &&
 #if defined(ARCH_64)
 	(timeout >> 32) == 0
@@ -3494,7 +3718,7 @@ gen_literal_timeout_locked(LoaderState* stp, GenOpArg Fail, GenOpArg Time)
 	1
 #endif
 	) {
-	op->a[1].val = timeout;
+	op->a[0].val = timeout;
 #if !defined(ARCH_64)
     } else if (Time.type == TAG_q) {
 	Eterm big;
@@ -3508,7 +3732,7 @@ gen_literal_timeout_locked(LoaderState* stp, GenOpArg Fail, GenOpArg Time)
 	} else {
 	    Uint u;
 	    (void) term_to_Uint(big, &u);
-	    op->a[1].val = (BeamInstr) u;
+	    op->a[0].val = (BeamInstr) u;
 	}
 #endif
     } else {
@@ -3554,7 +3778,7 @@ gen_select_tuple_arity(LoaderState* stp, GenOpArg S, GenOpArg Fail,
     if (size == 2) {
 	NEW_GENOP(stp, op);
 	op->next = NULL;
-	op->op = genop_i_select_tuple_arity2_6;
+	op->op = genop_i_select_tuple_arity2_4;
 	GENOP_ARITY(op, arity - 1);
 	op->a[0] = S;
 	op->a[1] = Fail;
@@ -3844,14 +4068,13 @@ gen_select_val(LoaderState* stp, GenOpArg S, GenOpArg Fail,
     int i, j, align = 0;
 
     if (size == 2) {
-
 	/*
 	 * Use a special-cased instruction if there are only two values.
 	 */
 
 	NEW_GENOP(stp, op);
 	op->next = NULL;
-	op->op = genop_i_select_val2_6;
+	op->op = genop_i_select_val2_4;
 	GENOP_ARITY(op, arity - 1);
 	op->a[0] = S;
 	op->a[1] = Fail;
@@ -3861,47 +4084,19 @@ gen_select_val(LoaderState* stp, GenOpArg S, GenOpArg Fail,
 	op->a[5] = Rest[3];
 
 	return op;
-
-    } else if (size > 10) {
-
-	/* binary search instruction */
-
-	NEW_GENOP(stp, op);
-	op->next = NULL;
-	op->op = genop_i_select_val_bins_3;
-	GENOP_ARITY(op, arity);
-	op->a[0] = S;
-	op->a[1] = Fail;
-	op->a[2].type = TAG_u;
-	op->a[2].val = size;
-	for (i = 3; i < arity; i++) {
-	    op->a[i] = Rest[i-3];
-	}
-
-	/*
-	 * Sort the values to make them useful for a binary search.
-	 */
-
-	qsort(op->a+3, size, 2*sizeof(GenOpArg),
-		(int (*)(const void *, const void *)) genopargcompare);
-#ifdef DEBUG
-	for (i = 3; i < arity-2; i += 2) {
-	    ASSERT(op->a[i].val < op->a[i+2].val);
-	}
-#endif
-	return op;
     }
 
-    /* linear search instruction */
-
-    align = 1;
+    if (size <= 10) {
+        /* Use linear search. Reserve place for a sentinel. */
+        align = 1;
+    }
 
     arity += 2*align;
     size  += align;
 
     NEW_GENOP(stp, op);
     op->next = NULL;
-    op->op = genop_i_select_val_lins_3;
+    op->op = (align == 0) ? genop_i_select_val_bins_3 : genop_i_select_val_lins_3;
     GENOP_ARITY(op, arity);
     op->a[0] = S;
     op->a[1] = Fail;
@@ -3915,7 +4110,7 @@ gen_select_val(LoaderState* stp, GenOpArg S, GenOpArg Fail,
     }
 
     /*
-     * Sort the values to make them useful for a sentinel search
+     * Sort the values to make them useful for a binary or sentinel search.
      */
 
     qsort(tmp, size - align, 2*sizeof(GenOpArg),
@@ -3930,11 +4125,12 @@ gen_select_val(LoaderState* stp, GenOpArg S, GenOpArg Fail,
 
     erts_free(ERTS_ALC_T_LOADER_TMP, (void *) tmp);
 
-    /* add sentinel */
-
-    op->a[j].type = TAG_u;
-    op->a[j].val  = ~((BeamInstr)0);
-    op->a[j+size] = Fail;
+    if (align) {
+        /* Add sentinel for linear search. */
+        op->a[j].type = TAG_u;
+        op->a[j].val  = ~((BeamInstr)0);
+        op->a[j+size] = Fail;
+    }
 
 #ifdef DEBUG
     for (i = 0; i < size - 1; i++) {
@@ -4222,6 +4418,92 @@ literal_is_map(LoaderState* stp, GenOpArg Lit)
 }
 
 /*
+ * Predicate to test whether all of the given new small map keys are literals
+ */
+static int
+is_small_map_literal_keys(LoaderState* stp, GenOpArg Size, GenOpArg* Rest)
+{
+    if (Size.val > MAP_SMALL_MAP_LIMIT) {
+        return 0;
+    }
+
+    /*
+     * Operations with non-literals have always only one key.
+     */
+    if (Size.val != 2) {
+        return 1;
+    }
+
+    switch (Rest[0].type) {
+    case TAG_a:
+    case TAG_i:
+    case TAG_n:
+    case TAG_q:
+        return 1;
+    default:
+        return 0;
+    }
+}
+
+static GenOp*
+gen_new_small_map_lit(LoaderState* stp, GenOpArg Dst, GenOpArg Live,
+                      GenOpArg Size, GenOpArg* Rest)
+{
+    unsigned size = Size.val;
+    Uint lit;
+    unsigned i;
+    GenOp* op;
+    GenOpArg* dst;
+    Eterm* hp;
+    Eterm* tmp;
+    Eterm* thp;
+    Eterm keys;
+
+    NEW_GENOP(stp, op);
+    GENOP_ARITY(op, 3 + size/2);
+    op->next = NULL;
+    op->op = genop_i_new_small_map_lit_3;
+
+    tmp = thp = erts_alloc(ERTS_ALC_T_LOADER_TMP, (1 + size/2) * sizeof(*tmp));
+    keys = make_tuple(thp);
+    *thp++ = make_arityval(size/2);
+
+    dst = op->a+3;
+
+    for (i = 0; i < size; i += 2) {
+        switch (Rest[i].type) {
+        case TAG_a:
+            *thp++ = Rest[i].val;
+            ASSERT(is_atom(Rest[i].val));
+            break;
+        case TAG_i:
+            *thp++ = make_small(Rest[i].val);
+            break;
+        case TAG_n:
+            *thp++ = NIL;
+            break;
+        case TAG_q:
+            *thp++ = stp->literals[Rest[i].val].term;
+            break;
+        }
+        *dst++ = Rest[i + 1];
+    }
+
+    if (!find_literal(stp, keys, &lit)) {
+        lit = new_literal(stp, &hp, 1 + size/2);
+        sys_memcpy(hp, tmp, (1 + size/2) * sizeof(*tmp));
+    }
+    erts_free(ERTS_ALC_T_LOADER_TMP, tmp);
+
+    op->a[0] = Dst;
+    op->a[1] = Live;
+    op->a[2].type = TAG_q;
+    op->a[2].val = lit;
+
+    return op;
+}
+
+/*
  * Predicate to test whether the given literal is an empty map.
  */
 
@@ -4732,21 +5014,57 @@ freeze_code(LoaderState* stp)
      */
 
     for (i = 0; i < stp->num_labels; i++) {
-	Sint this_patch;
-	Sint next_patch;
+	Uint patch;
 	Uint value = stp->labels[i].value;
-	
-	if (value == 0 && stp->labels[i].patches >= 0) {
+
+	if (value == 0 && stp->labels[i].num_patches != 0) {
 	    LoadError1(stp, "label %d not resolved", i);
 	}
 	ASSERT(value < stp->ci);
-	this_patch = stp->labels[i].patches;
-	while (this_patch >= 0) {
-	    ASSERT(this_patch < stp->ci);
-	    next_patch = codev[this_patch];
-	    ASSERT(next_patch < stp->ci);
-	    codev[this_patch] = (BeamInstr) (codev + value);
-	    this_patch = next_patch;
+        for (patch = 0; patch < stp->labels[i].num_patches; patch++) {
+            LabelPatch* lp = &stp->labels[i].patches[patch];
+            Uint pos = lp->pos;
+	    ASSERT(pos < stp->ci);
+            if (pos < stp->num_functions) {
+                /*
+                 * This is the array of pointers to the beginning of
+                 * each function. The pointers must remain absolute.
+                 */
+                codev[pos] = (BeamInstr) (codev + value);
+            } else {
+#if defined(DEBUG) && defined(BEAM_WIDE_MASK)
+                Uint w;
+#endif
+                Sint32 rel = lp->offset + value;
+                switch (lp->packed) {
+                case 0:         /* Not packed */
+                    ASSERT(codev[pos] == i);
+                    codev[pos] = rel;
+                    break;
+#ifdef BEAM_WIDE_MASK
+                case 1:         /* Least significant word. */
+#ifdef DEBUG
+                    w = codev[pos] & BEAM_WIDE_MASK;
+                    /* Correct label in least significant word? */
+                    ASSERT(w == i);
+#endif
+                    codev[pos] = (codev[pos] & ~BEAM_WIDE_MASK) |
+                        (rel & BEAM_WIDE_MASK);
+                    break;
+                case 2:         /* Most significant word */
+#ifdef DEBUG
+                    w = (codev[pos] >> BEAM_WIDE_SHIFT) & BEAM_WIDE_MASK;
+                    /* Correct label in most significant word? */
+                    ASSERT(w == i);
+#endif
+                    codev[pos] = ((Uint)rel << BEAM_WIDE_SHIFT) |
+                        (codev[pos] & BEAM_WIDE_MASK);
+                    break;
+#endif
+                default:
+                    ASSERT(0);
+                }
+            }
 	}
     }
     CHKBLK(ERTS_ALC_T_CODE,code_hdr);
@@ -4789,8 +5107,11 @@ final_touch(LoaderState* stp, struct erl_module_instance* inst_p)
     catches = BEAM_CATCHES_NIL;
     while (index != 0) {
 	BeamInstr next = codev[index];
-	codev[index] = BeamOpCode(op_catch_yf);
-	catches = beam_catches_cons((BeamInstr *)codev[index+2], catches);
+        BeamInstr* abs_addr;
+	codev[index] = BeamOpCodeAddr(op_catch_yf);
+        /* We must make the address of the label absolute again. */
+        abs_addr = (BeamInstr *)codev + index + codev[index+2];
+	catches = beam_catches_cons(abs_addr, catches);
 	codev[index+2] = make_catch(catches);
 	index = next;
     }
@@ -4861,7 +5182,7 @@ final_touch(LoaderState* stp, struct erl_module_instance* inst_p)
 		/*
 		 * We are hiding a pointer into older code.
 		 */
-		erts_smp_refc_dec(&fe->refc, 1);
+		erts_refc_dec(&fe->refc, 1);
 	    }
 	    fe->address = code_ptr;
 #ifdef HIPE
@@ -5257,12 +5578,15 @@ get_tag_and_value(LoaderState* stp, Uint len_code,
 {
     Uint count;
     Sint val;
-    byte default_buf[128];
-    byte* bigbuf = default_buf;
+    byte default_byte_buf[128];
+    byte* byte_buf = default_byte_buf;
+    Eterm default_big_buf[128/sizeof(Eterm)];
+    Eterm* big_buf = default_big_buf;
+    Eterm tmp_big;
     byte* s;
     int i;
     int neg = 0;
-    Uint arity;
+    Uint words_needed;
     Eterm* hp;
 
     /*
@@ -5339,8 +5663,11 @@ get_tag_and_value(LoaderState* stp, Uint len_code,
 	    *result = val;
 	    return TAG_i;
 	} else {
-	    *result = new_literal(stp, &hp, BIG_UINT_HEAP_SIZE);
-	    (void) small_to_big(val, hp);
+            tmp_big = small_to_big(val, big_buf);
+            if (!find_literal(stp, tmp_big, result)) {
+                *result = new_literal(stp, &hp, BIG_UINT_HEAP_SIZE);
+                sys_memcpy(hp, big_buf, BIG_UINT_HEAP_SIZE*sizeof(Eterm));
+            }
 	    return TAG_q;
 	}
     }
@@ -5350,8 +5677,8 @@ get_tag_and_value(LoaderState* stp, Uint len_code,
      * (including margin).
      */
 
-    if (count+8 > sizeof(default_buf)) {
-	bigbuf = erts_alloc(ERTS_ALC_T_LOADER_TMP, count+8);
+    if (count+8 > sizeof(default_byte_buf)) {
+	byte_buf = erts_alloc(ERTS_ALC_T_LOADER_TMP, count+8);
     }
 
     /*
@@ -5360,20 +5687,20 @@ get_tag_and_value(LoaderState* stp, Uint len_code,
 
     GetString(stp, s, count);
     for (i = 0; i < count; i++) {
-	bigbuf[count-i-1] = *s++;
+	byte_buf[count-i-1] = *s++;
     }
 
     /*
      * Check if the number is negative, and negate it if so.
      */
 
-    if ((bigbuf[count-1] & 0x80) != 0) {
+    if ((byte_buf[count-1] & 0x80) != 0) {
 	unsigned carry = 1;
 
 	neg = 1;
 	for (i = 0; i < count; i++) {
-	    bigbuf[i] = ~bigbuf[i] + carry;
-	    carry = (bigbuf[i] == 0 && carry == 1);
+	    byte_buf[i] = ~byte_buf[i] + carry;
+	    carry = (byte_buf[i] == 0 && carry == 1);
 	}
 	ASSERT(carry == 0);
     }
@@ -5382,33 +5709,52 @@ get_tag_and_value(LoaderState* stp, Uint len_code,
      * Align to word boundary.
      */
 
-    if (bigbuf[count-1] == 0) {
+    if (byte_buf[count-1] == 0) {
 	count--;
     }
-    if (bigbuf[count-1] == 0) {
+    if (byte_buf[count-1] == 0) {
 	LoadError0(stp, "bignum not normalized");
     }
     while (count % sizeof(Eterm) != 0) {
-	bigbuf[count++] = 0;
+	byte_buf[count++] = 0;
     }
 
     /*
-     * Allocate heap space for the bignum and copy it.
+     * Convert to a bignum.
      */
 
-    arity = count/sizeof(Eterm);
-    *result = new_literal(stp, &hp, arity+1);
-    if (is_nil(bytes_to_big(bigbuf, count, neg, hp)))
-	goto load_error;
+    words_needed = count/sizeof(Eterm) + 1;
+    if (words_needed*sizeof(Eterm) > sizeof(default_big_buf)) {
+        big_buf = erts_alloc(ERTS_ALC_T_LOADER_TMP, words_needed*sizeof(Eterm));
+    }
+    tmp_big = bytes_to_big(byte_buf, count, neg, big_buf);
+    if (is_nil(tmp_big)) {
+        goto load_error;
+    }
+
+    /*
+     * Create a literal if there is no previous literal with the same value.
+     */
+
+    if (!find_literal(stp, tmp_big, result)) {
+        *result = new_literal(stp, &hp, words_needed);
+        sys_memcpy(hp, big_buf, words_needed*sizeof(Eterm));
+    }
 
-    if (bigbuf != default_buf) {
-	erts_free(ERTS_ALC_T_LOADER_TMP, (void *) bigbuf);
+    if (byte_buf != default_byte_buf) {
+	erts_free(ERTS_ALC_T_LOADER_TMP, (void *) byte_buf);
+    }
+    if (big_buf != default_big_buf) {
+	erts_free(ERTS_ALC_T_LOADER_TMP, (void *) big_buf);
     }
     return TAG_q;
 
  load_error:
-    if (bigbuf != default_buf) {
-	erts_free(ERTS_ALC_T_LOADER_TMP, (void *) bigbuf);
+    if (byte_buf != default_byte_buf) {
+	erts_free(ERTS_ALC_T_LOADER_TMP, (void *) byte_buf);
+    }
+    if (big_buf != default_big_buf) {
+	erts_free(ERTS_ALC_T_LOADER_TMP, (void *) big_buf);
     }
     return -1;
 }
@@ -5453,8 +5799,7 @@ new_label(LoaderState* stp)
     stp->labels = (Label *) erts_realloc(ERTS_ALC_T_PREPARED_CODE,
 					 (void *) stp->labels,
 					 stp->num_labels * sizeof(Label));
-    stp->labels[num].value = 0;
-    stp->labels[num].patches = -1;
+    init_label(&stp->labels[num]);
     return num;
 }
 
@@ -5509,6 +5854,24 @@ new_literal(LoaderState* stp, Eterm** hpp, Uint heap_size)
     return stp->num_literals++;
 }
 
+static int
+find_literal(LoaderState* stp, Eterm needle, Uint *idx)
+{
+    int i;
+
+    /*
+     * The search is done backwards since the most recent literals
+     * allocated by the loader itself will be placed at the end
+     */
+    for (i = stp->num_literals - 1; i >= 0; i--) {
+        if (EQ(needle, stp->literals[i].term)) {
+            *idx = (Uint) i;
+            return 1;
+        }
+    }
+    return 0;
+}
+
 Eterm
 erts_module_info_0(Process* p, Eterm module)
 {
@@ -5677,7 +6040,7 @@ erts_release_literal_area(ErtsLiteralArea* literal_area)
         case FUN_SUBTAG:
             {
                 ErlFunEntry* fe = ((ErlFunThing*)oh)->fe;
-                if (erts_smp_refc_dectest(&fe->refc, 0) == 0) {
+                if (erts_refc_dectest(&fe->refc, 0) == 0) {
                     erts_erase_fun_entry(fe);
                 }
                 break;
@@ -5722,9 +6085,9 @@ int
 erts_is_function_native(ErtsCodeInfo *ci)
 {
 #ifdef HIPE
-    ASSERT(ci->op == (BeamInstr) BeamOp(op_i_func_info_IaaI));
-    return erts_codeinfo_to_code(ci)[0] == (BeamInstr) BeamOp(op_hipe_trap_call)
-	|| erts_codeinfo_to_code(ci)[0] == (BeamInstr) BeamOp(op_hipe_trap_call_closure);
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
+    return BeamIsOpCode(erts_codeinfo_to_code(ci)[0], op_hipe_trap_call) ||
+	BeamIsOpCode(erts_codeinfo_to_code(ci)[0], op_hipe_trap_call_closure);
 #else
     return 0;
 #endif
@@ -5793,7 +6156,7 @@ exported_from_module(Process* p, /* Process whose heap to use. */
 	    Eterm tuple;
 	    
 	    if (ep->addressv[code_ix] == ep->beam &&
-		ep->beam[0] == (BeamInstr) em_call_error_handler) {
+		BeamIsOpCode(ep->beam[0], op_call_error_handler)) {
 		/* There is a call to the function, but it does not exist. */ 
 		continue;
 	    }
@@ -6064,7 +6427,7 @@ make_stub(ErtsCodeInfo* info, Eterm mod, Eterm func, Uint arity, Uint native, Be
 {
     DBG_TRACE_MFA(mod,func,arity,"make beam stub at %p", erts_codeinfo_to_code(info));
     ASSERT(WORDS_PER_FUNCTION == 6);
-    info->op = (BeamInstr) BeamOp(op_i_func_info_IaaI);
+    info->op = BeamOpCodeAddr(op_i_func_info_IaaI);
     info->u.ncallee = (void (*)(void)) native;
     info->mfa.module = mod;
     info->mfa.function = func;
@@ -6169,7 +6532,7 @@ stub_final_touch(LoaderState* stp, ErtsCodeInfo* ci)
     for (i = 0, lp = stp->lambdas; i < n; i++, lp++) {
         ErlFunEntry* fe = stp->lambdas[i].fe;
 	if (lp->function == ci->mfa.function && lp->arity == ci->mfa.arity) {
-	    *erts_codeinfo_to_code(ci) = (Eterm) BeamOpCode(op_hipe_trap_call_closure);
+	    *erts_codeinfo_to_code(ci) = BeamOpCodeAddr(op_hipe_trap_call_closure);
             fe->address = erts_codeinfo_to_code(ci);
 	}
     }
@@ -6299,7 +6662,7 @@ patch_funentries(Eterm Patchlist)
     fe = erts_get_fun_entry(Mod, uniq, index);
     fe->native_address = (Uint *)native_address;
 
-    erts_smp_refc_dec(&fe->refc, 1);
+    erts_refc_dec(&fe->refc, 1);
 
     if (!patch(Addresses, (Uint) fe))
       return 0;
@@ -6493,7 +6856,7 @@ erts_make_stub_module(Process* p, Eterm hipe_magic_bin, Eterm Beam, Eterm Info)
 	 * as the body until we know what kind of trap we should put there.
 	 */
 	code_hdr->functions[i] = (ErtsCodeInfo*)fp;
-	op = (Eterm) BeamOpCode(op_hipe_trap_call); /* Might be changed later. */
+	op = BeamOpCodeAddr(op_hipe_trap_call); /* Might be changed later. */
 	fp = make_stub((ErtsCodeInfo*)fp, hipe_stp->module, func, arity,
                        (Uint)native_address, op);
     }
@@ -6503,7 +6866,7 @@ erts_make_stub_module(Process* p, Eterm hipe_magic_bin, Eterm Beam, Eterm Info)
      */
 
     code_hdr->functions[i] = (ErtsCodeInfo*)fp;
-    *fp++ = (BeamInstr) BeamOp(op_int_code_end);
+    *fp++ = BeamOpCodeAddr(op_int_code_end);
 
     /*
      * Copy attributes and compilation information.
diff --git a/erts/emulator/beam/beam_load.h b/erts/emulator/beam/beam_load.h
index c088bdb751..156c3c45e2 100644
--- a/erts/emulator/beam/beam_load.h
+++ b/erts/emulator/beam/beam_load.h
@@ -37,11 +37,6 @@ typedef struct gen_op_entry {
 
 extern const GenOpEntry gen_opc[];
 
-extern BeamInstr beam_debug_apply[];
-extern BeamInstr* em_call_error_handler;
-extern BeamInstr* em_apply_bif;
-extern BeamInstr* em_call_nif;
-
 struct ErtsLiteralArea_;
 
 /*
@@ -111,11 +106,7 @@ typedef struct beam_code_header {
 
 }BeamCodeHeader;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 #  define BEAM_NIF_MIN_FUNC_SZ 4
-#else
-#  define BEAM_NIF_MIN_FUNC_SZ 3
-#endif
 
 void erts_release_literal_area(struct ErtsLiteralArea_* literal_area);
 int erts_is_module_native(BeamCodeHeader* code);
diff --git a/erts/emulator/beam/beam_ranges.c b/erts/emulator/beam/beam_ranges.c
index fac4289271..01bda7f3c1 100644
--- a/erts/emulator/beam/beam_ranges.c
+++ b/erts/emulator/beam/beam_ranges.c
@@ -29,7 +29,7 @@
 
 typedef struct {
     BeamInstr* start;		/* Pointer to start of module. */
-    erts_smp_atomic_t end; /* (BeamInstr*) Points one word beyond last function in module. */
+    erts_atomic_t end; /* (BeamInstr*) Points one word beyond last function in module. */
 } Range;
 
 /*
@@ -43,7 +43,7 @@ Uint erts_dump_num_lit_areas;
 
 /* Range 'end' needs to be atomic as we purge module
     by setting end=start in active code_ix */
-#define RANGE_END(R) ((BeamInstr*)erts_smp_atomic_read_nob(&(R)->end))
+#define RANGE_END(R) ((BeamInstr*)erts_atomic_read_nob(&(R)->end))
 
 static Range* find_range(BeamInstr* pc);
 static void lookup_loc(FunctionInfo* fi, const BeamInstr* pc,
@@ -58,10 +58,10 @@ struct ranges {
     Range* modules;	       /* Sorted lists of module addresses. */
     Sint n;		       /* Number of range entries. */
     Sint allocated;	       /* Number of allocated entries. */
-    erts_smp_atomic_t mid;     /* Cached search start point */
+    erts_atomic_t mid;     /* Cached search start point */
 };
 static struct ranges r[ERTS_NUM_CODE_IX];
-static erts_smp_atomic_t mem_used;
+static erts_atomic_t mem_used;
 static Range* write_ptr;
 
 #ifdef HARD_DEBUG
@@ -99,12 +99,12 @@ erts_init_ranges(void)
 {
     Sint i;
 
-    erts_smp_atomic_init_nob(&mem_used, 0);
+    erts_atomic_init_nob(&mem_used, 0);
     for (i = 0; i < ERTS_NUM_CODE_IX; i++) {
 	r[i].modules = 0;
 	r[i].n = 0;
 	r[i].allocated = 0;
-	erts_smp_atomic_init_nob(&r[i].mid, 0);
+	erts_atomic_init_nob(&r[i].mid, 0);
     }
 
     erts_dump_num_lit_areas = 8;
@@ -121,12 +121,12 @@ erts_start_staging_ranges(int num_new)
     Sint need;
 
     if (r[dst].modules) {
-	erts_smp_atomic_add_nob(&mem_used, -r[dst].allocated);
+	erts_atomic_add_nob(&mem_used, -r[dst].allocated);
 	erts_free(ERTS_ALC_T_MODULE_REFS, r[dst].modules);
     }
 
     need = r[dst].allocated = r[src].n + num_new;
-    erts_smp_atomic_add_nob(&mem_used, need);
+    erts_atomic_add_nob(&mem_used, need);
     write_ptr = erts_alloc(ERTS_ALC_T_MODULE_REFS,
 			   need * sizeof(Range));
     r[dst].modules = write_ptr;
@@ -149,7 +149,7 @@ erts_end_staging_ranges(int commit)
 	    if (rp->start < RANGE_END(rp)) {
 		/* Only insert a module that has not been purged. */
 		write_ptr->start = rp->start;
-		erts_smp_atomic_init_nob(&write_ptr->end,
+		erts_atomic_init_nob(&write_ptr->end,
 					 (erts_aint_t)(RANGE_END(rp)));
 		write_ptr++;
 	    }
@@ -175,7 +175,7 @@ erts_end_staging_ranges(int commit)
 	}
 	r[dst].modules = mp;
 	CHECK(&r[dst]);
-	erts_smp_atomic_set_nob(&r[dst].mid,
+	erts_atomic_set_nob(&r[dst].mid,
 				(erts_aint_t) (r[dst].modules +
 					       r[dst].n / 2));
 
@@ -204,7 +204,7 @@ erts_update_ranges(BeamInstr* code, Uint size)
 	 */
 	if (r[dst].modules == NULL) {
 	    Sint need = 128;
-	    erts_smp_atomic_add_nob(&mem_used, need);
+	    erts_atomic_add_nob(&mem_used, need);
 	    r[dst].modules = erts_alloc(ERTS_ALC_T_MODULE_REFS,
 					need * sizeof(Range));
 	    r[dst].allocated = need;
@@ -214,7 +214,7 @@ erts_update_ranges(BeamInstr* code, Uint size)
 
     ASSERT(r[dst].modules);
     write_ptr->start = code;
-    erts_smp_atomic_init_nob(&(write_ptr->end),
+    erts_atomic_init_nob(&(write_ptr->end),
 			     (erts_aint_t)(((byte *)code) + size));
     write_ptr++;
 }
@@ -223,13 +223,13 @@ void
 erts_remove_from_ranges(BeamInstr* code)
 {
     Range* rp = find_range(code);
-    erts_smp_atomic_set_nob(&rp->end, (erts_aint_t)rp->start);
+    erts_atomic_set_nob(&rp->end, (erts_aint_t)rp->start);
 }
 
 UWord
 erts_ranges_sz(void)
 {
-    return erts_smp_atomic_read_nob(&mem_used) * sizeof(Range);
+    return erts_atomic_read_nob(&mem_used) * sizeof(Range);
 }
 
 /*
@@ -284,7 +284,7 @@ find_range(BeamInstr* pc)
     ErtsCodeIndex active = erts_active_code_ix();
     Range* low = r[active].modules;
     Range* high = low + r[active].n;
-    Range* mid = (Range *) erts_smp_atomic_read_nob(&r[active].mid);
+    Range* mid = (Range *) erts_atomic_read_nob(&r[active].mid);
 
     CHECK(&r[active]);
     while (low < high) {
@@ -293,7 +293,7 @@ find_range(BeamInstr* pc)
 	} else if (pc >= RANGE_END(mid)) {
 	    low = mid + 1;
 	} else {
-	    erts_smp_atomic_set_nob(&r[active].mid, (erts_aint_t) mid);
+	    erts_atomic_set_nob(&r[active].mid, (erts_aint_t) mid);
 	    return mid;
 	}
 	mid = low + (high-low) / 2;
diff --git a/erts/emulator/beam/bif.c b/erts/emulator/beam/bif.c
index b6595d2a5d..0e5f7bb22b 100644
--- a/erts/emulator/beam/bif.c
+++ b/erts/emulator/beam/bif.c
@@ -57,10 +57,11 @@ static Export dsend_continue_trap_export;
 Export *erts_convert_time_unit_trap = NULL;
 
 static Export *await_msacc_mod_trap = NULL;
-static erts_smp_atomic32_t msacc;
+static erts_atomic32_t msacc;
 
+static Export *system_flag_scheduler_wall_time_trap;
 static Export *await_sched_wall_time_mod_trap;
-static erts_smp_atomic32_t sched_wall_time;
+static erts_atomic32_t sched_wall_time;
 
 #define DECL_AM(S) Eterm AM_ ## S = am_atom_put(#S, sizeof(#S) - 1)
 
@@ -98,14 +99,12 @@ static int insert_internal_link(Process* p, Eterm rpid)
 
     ASSERT(is_internal_pid(rpid));
 
-#ifdef ERTS_SMP
     if (IS_TRACED(p)
 	&& (ERTS_TRACE_FLAGS(p) & (F_TRACE_SOL|F_TRACE_SOL1))) {
 	rp_locks = ERTS_PROC_LOCKS_ALL;
     }
 
-    erts_smp_proc_lock(p, ERTS_PROC_LOCK_LINK);
-#endif
+    erts_proc_lock(p, ERTS_PROC_LOCK_LINK);
 
     /* get a pointer to the process struct of the linked process */
     rp = erts_pid2proc_opt(p, ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_LINK,
@@ -113,7 +112,7 @@ static int insert_internal_link(Process* p, Eterm rpid)
 			   ERTS_P2P_FLG_ALLOW_OTHER_X);
 
     if (!rp) {
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(p, ERTS_PROC_LOCK_LINK);
 	return 0;
     }
 
@@ -139,10 +138,10 @@ static int insert_internal_link(Process* p, Eterm rpid)
                    rp, am_getting_linked, p->common.id);
 
     if (p == rp)
-	erts_smp_proc_unlock(p, rp_locks & ~ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(p, rp_locks & ~ERTS_PROC_LOCK_MAIN);
     else {
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_LINK);
-	erts_smp_proc_unlock(rp, rp_locks);
+	erts_proc_unlock(p, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(rp, rp_locks);
     }
 
     return 1;
@@ -178,13 +177,13 @@ BIF_RETTYPE link_1(BIF_ALIST_1)
 	    goto res_no_proc;
 	}
 
-	erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK);
+	erts_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK);
 	
 	if (erts_add_link(&ERTS_P_LINKS(BIF_P), LINK_PID, BIF_ARG_1) >= 0)
 	    send_link_signal = 1;
 	/* else: already linked */
 
-	erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
 
 	if (send_link_signal) {
 	    Eterm ref;
@@ -212,11 +211,11 @@ BIF_RETTYPE link_1(BIF_ALIST_1)
 
     if (is_external_pid(BIF_ARG_1)) {
 
-	erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK);
+	erts_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK);
 
 	/* We may earn time by checking first that we're not linked already */
 	if (erts_lookup_link(ERTS_P_LINKS(BIF_P), BIF_ARG_1) != NULL) {
-	    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
+	    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
 	    BIF_RET(am_true);
 	}
 	else {
@@ -225,22 +224,43 @@ BIF_RETTYPE link_1(BIF_ALIST_1)
 	    ErtsDSigData dsd;
 	    dep = external_pid_dist_entry(BIF_ARG_1);
 	    if (dep == erts_this_dist_entry) {
-		erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
+		erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
 		goto res_no_proc;
 	    }
 
-	    code = erts_dsig_prepare(&dsd, dep, BIF_P, ERTS_DSP_RLOCK, 0);
+	    code = erts_dsig_prepare(&dsd, dep, BIF_P,
+				     (ERTS_PROC_LOCK_MAIN | ERTS_PROC_LOCK_LINK),
+				     ERTS_DSP_RLOCK, 0, 1);
 	    switch (code) {
 	    case ERTS_DSIG_PREP_NOT_ALIVE:
-		/* Let the dlink trap handle it */
-	    case ERTS_DSIG_PREP_NOT_CONNECTED:
-		erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
-		BIF_TRAP1(dlink_trap, BIF_P, BIF_ARG_1);
-
+	    case ERTS_DSIG_PREP_NOT_CONNECTED: {
+		ErtsProcLocks locks = ERTS_PROC_LOCK_MAIN | ERTS_PROC_LOCK_LINK;
+		erts_aint32_t state;
+		erts_proc_lock(BIF_P, (ERTS_PROC_LOCKS_ALL & ~locks));
+		locks = ERTS_PROC_LOCKS_ALL;
+		erts_send_exit_signal(BIF_P, BIF_ARG_1, BIF_P, &locks,
+				      am_noconnection, NIL, NULL, 0);
+		erts_proc_unlock(BIF_P, locks & ERTS_PROC_LOCKS_ALL_MINOR);
+
+		/*
+		 * Copy-paste from old dist_exit_3, not sure if we really
+		 * need erts_handle_pending_exit when exit_2 does not.
+		 */
+		state = erts_atomic32_read_acqb(&BIF_P->state);
+		if (state & (ERTS_PSFLG_EXITING|ERTS_PSFLG_PENDING_EXIT)) {
+		    if (state & ERTS_PSFLG_PENDING_EXIT)
+			erts_handle_pending_exit(BIF_P, ERTS_PROC_LOCK_MAIN);
+		    ERTS_BIF_EXITED(BIF_P);
+		}
+		BIF_RET(am_true);
+	    }
+            case ERTS_DSIG_PREP_PENDING:
 	    case ERTS_DSIG_PREP_CONNECTED:
-		/* We are connected. Setup link and send link signal */
-
-		erts_smp_de_links_lock(dep);
+                /*
+                 * We have (pending) connection.
+                 * Setup link and enqueue link signal.
+                 */
+		erts_de_links_lock(dep);
 
 		erts_add_link(&ERTS_P_LINKS(BIF_P), LINK_PID, BIF_ARG_1);
 		lnk = erts_add_or_lookup_link(&(dep->nlinks),
@@ -249,17 +269,16 @@ BIF_RETTYPE link_1(BIF_ALIST_1)
 		ASSERT(lnk != NULL);
 		erts_add_link(&ERTS_LINK_ROOT(lnk), LINK_PID, BIF_ARG_1);
 
-		erts_smp_de_links_unlock(dep);
-		erts_smp_de_runlock(dep);
-		erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
+		erts_de_links_unlock(dep);
+		erts_de_runlock(dep);
+		erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
 
 		code = erts_dsig_send_link(&dsd, BIF_P->common.id, BIF_ARG_1);
 		if (code == ERTS_DSIG_SEND_YIELD)
 		    ERTS_BIF_YIELD_RETURN(BIF_P, am_true);
 		BIF_RET(am_true);
 	    default:
-		ASSERT(! "Invalid dsig prepare result");
-		BIF_ERROR(BIF_P, EXC_INTERNAL_ERROR);
+		ERTS_ASSERT(! "Invalid dsig prepare result");
 	    }
 	}
     }
@@ -267,11 +286,11 @@ BIF_RETTYPE link_1(BIF_ALIST_1)
     BIF_ERROR(BIF_P, BADARG);
 
 res_no_proc: {
-	erts_aint32_t state = erts_smp_atomic32_read_nob(&BIF_P->state);
+	erts_aint32_t state = erts_atomic32_read_nob(&BIF_P->state);
 	if (state & ERTS_PSFLG_TRAP_EXIT) {
 	    ErtsProcLocks locks = ERTS_PROC_LOCK_MAIN;
 	    erts_deliver_exit_message(BIF_ARG_1, BIF_P, &locks, am_noproc, NIL);
-	    erts_smp_proc_unlock(BIF_P, ~ERTS_PROC_LOCK_MAIN & locks);
+	    erts_proc_unlock(BIF_P, ~ERTS_PROC_LOCK_MAIN & locks);
 	    BIF_RET(am_true);
 	}
 	else
@@ -290,58 +309,43 @@ remote_demonitor(Process *c_p, DistEntry *dep, Eterm ref, Eterm to)
     ErtsMonitor *mon;
     int code;
     Eterm res = am_false;
-#ifndef ERTS_SMP
-    int stale_mon = 0;
-#endif
 
-    ERTS_SMP_LC_ASSERT((ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_LINK)
+    ERTS_LC_ASSERT((ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_LINK)
 		       == erts_proc_lc_my_proc_locks(c_p));
 
-    code = erts_dsig_prepare(&dsd, dep, c_p, ERTS_DSP_RLOCK, 0);
+    code = erts_dsig_prepare(&dsd, dep, c_p, ERTS_PROC_LOCK_MAIN,
+			     ERTS_DSP_RLOCK, 0, 0);
     switch (code) {
     case ERTS_DSIG_PREP_NOT_ALIVE:
     case ERTS_DSIG_PREP_NOT_CONNECTED:
-#ifndef ERTS_SMP
-	/* XXX Is this possible? Shouldn't this link
-	   previously have been removed if the node
-	   had previously been disconnected. */
-	ASSERT(0);
-	stale_mon = 1;
-#endif
 	/*
 	 * In the smp case this is possible if the node goes
 	 * down just before the call to demonitor.
 	 */
 	if (dep) {
-	    erts_smp_de_links_lock(dep);
+	    erts_de_links_lock(dep);
 	    dmon = erts_remove_monitor(&dep->monitors, ref);
-	    erts_smp_de_links_unlock(dep);
+	    erts_de_links_unlock(dep);
 	    if (dmon)
 		erts_destroy_monitor(dmon);
 	}
 	mon = erts_remove_monitor(&ERTS_P_MONITORS(c_p), ref);
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_LINK);
 
         res = am_true;
 	break;
 
+    case ERTS_DSIG_PREP_PENDING:
     case ERTS_DSIG_PREP_CONNECTED:
 
-	erts_smp_de_links_lock(dep);
+	erts_de_links_lock(dep);
 	mon = erts_remove_monitor(&ERTS_P_MONITORS(c_p), ref);
 	dmon = erts_remove_monitor(&dep->monitors, ref);
-	erts_smp_de_links_unlock(dep);
-	erts_smp_de_runlock(dep);
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_LINK);
+	erts_de_links_unlock(dep);
+	erts_de_runlock(dep);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_LINK);
 
 	if (!dmon) {
-#ifndef ERTS_SMP
-	    /* XXX How is this possible? Shouldn't this link
-	       previously have been removed when the distributed
-	       end was removed. */
-	    ASSERT(0);
-	    stale_mon = 1;
-#endif
 	    /*
 	     * This is possible when smp support is enabled.
 	     * 'DOWN' message just arrived.
@@ -366,22 +370,9 @@ remote_demonitor(Process *c_p, DistEntry *dep, Eterm ref, Eterm to)
 	}
 	break;
     default:
-	ASSERT(! "Invalid dsig prepare result");
-        return am_internal_error;
+	ERTS_ASSERT(! "Invalid dsig prepare result");
     }
 
-#ifndef ERTS_SMP
-    if (stale_mon) {
-	erts_dsprintf_buf_t *dsbufp = erts_create_logger_dsbuf();
-	erts_dsprintf(dsbufp, "Stale process monitor %T to ", ref);
-	if (is_atom(to))
-	    erts_dsprintf(dsbufp, "{%T, %T}", to, dep->sysname);
-	else
-	    erts_dsprintf(dsbufp, "%T", to);
-	erts_dsprintf(dsbufp, " found\n");
-	erts_send_error_to_logger(c_p->group_leader, dsbufp);
-    }
-#endif
 
     /*
      * We aren't allowed to destroy 'mon' until now, since 'to'
@@ -391,7 +382,7 @@ remote_demonitor(Process *c_p, DistEntry *dep, Eterm ref, Eterm to)
 		    lookup and remove */
     erts_destroy_monitor(mon);
 
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(c_p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(c_p));
     return res;
 }
 
@@ -405,13 +396,9 @@ demonitor_local_process(Process *c_p, Eterm ref, Eterm to, Eterm *res)
                            ERTS_P2P_FLG_ALLOW_OTHER_X);
     ErtsMonitor *mon = erts_remove_monitor(&ERTS_P_MONITORS(c_p), ref);
 
-#ifndef ERTS_SMP
-    ASSERT(mon);
-#else
     if (!mon)
         *res = am_false;
     else
-#endif
     {
         *res = am_true;
         erts_destroy_monitor(mon);
@@ -420,12 +407,12 @@ demonitor_local_process(Process *c_p, Eterm ref, Eterm to, Eterm *res)
         ErtsMonitor *rmon;
         rmon = erts_remove_monitor(&ERTS_P_MONITORS(rp), ref);
         if (rp != c_p)
-            erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+            erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
         if (rmon != NULL)
             erts_destroy_monitor(rmon);
     }
     else {
-        ERTS_SMP_ASSERT_IS_NOT_EXITING(c_p);
+        ERTS_ASSERT_IS_NOT_EXITING(c_p);
     }
 }
 
@@ -438,7 +425,7 @@ demonitor_local_port(Process *origin, Eterm ref, Eterm target)
     if (!port) {
         BIF_ERROR(origin, BADARG);
     }
-    erts_smp_proc_unlock(origin, ERTS_PROC_LOCK_LINK);
+    erts_proc_unlock(origin, ERTS_PROC_LOCK_LINK);
 
     if (port) {
         Eterm trap_ref;
@@ -458,7 +445,7 @@ demonitor_local_port(Process *origin, Eterm ref, Eterm target)
         }
     }
     else {
-        ERTS_SMP_ASSERT_IS_NOT_EXITING(origin);
+        ERTS_ASSERT_IS_NOT_EXITING(origin);
     }
     BIF_RET(res);
 }
@@ -472,11 +459,10 @@ BIF_RETTYPE demonitor(Process *c_p, Eterm ref, Eterm *multip)
    ErtsMonitor  *mon = NULL;  /* The monitor entry to delete */
    Eterm        to = NIL;     /* Monitor link traget */
    DistEntry    *dep = NULL;  /* Target's distribution entry */
-   int          deref_de = 0;
    BIF_RETTYPE  res = am_false;
    int          unlock_link = 1;
 
-   erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_LINK);
+   erts_proc_lock(c_p, ERTS_PROC_LOCK_LINK);
 
    if (is_not_internal_ref(ref)) {
        res = am_badarg;
@@ -502,8 +488,6 @@ BIF_RETTYPE demonitor(Process *c_p, Eterm ref, Eterm *multip)
            ASSERT(is_node_name_atom(to));
            dep = erts_sysname_to_connected_dist_entry(to);
            ASSERT(dep != erts_this_dist_entry);
-           if (dep)
-               deref_de = 1;
        } else if (is_port(to)) {
            if (port_dist_entry(to) != erts_this_dist_entry) {
                goto badarg;
@@ -521,11 +505,6 @@ BIF_RETTYPE demonitor(Process *c_p, Eterm ref, Eterm *multip)
            unlock_link = 0;
        }
        else { /* Local monitor */
-           if (deref_de) {
-               deref_de = 0;
-               erts_deref_dist_entry(dep);
-           }
-           dep = NULL;
            demonitor_local_process(c_p, ref, to, &res);
        }
        break;
@@ -538,14 +517,9 @@ badarg:
 done:
 
    if (unlock_link)
-       erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_LINK);
+       erts_proc_unlock(c_p, ERTS_PROC_LOCK_LINK);
 
-   if (deref_de) {
-       ASSERT(dep);
-       erts_deref_dist_entry(dep);
-   }
-
-   ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(c_p));
+   ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(c_p));
    BIF_RET(res);
 }
 
@@ -668,12 +642,12 @@ local_pid_monitor(Process *p, Eterm target, Eterm mon_ref, int boolean)
 	return ret;
     }
 
-    erts_smp_proc_lock(p, ERTS_PROC_LOCK_LINK);
+    erts_proc_lock(p, ERTS_PROC_LOCK_LINK);
     rp = erts_pid2proc_opt(p, p_locks,
 			   target, ERTS_PROC_LOCK_LINK,
 			   ERTS_P2P_FLG_ALLOW_OTHER_X);
     if (!rp) {
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(p, ERTS_PROC_LOCK_LINK);
 	p_locks &= ~ERTS_PROC_LOCK_LINK;
 	if (boolean)
 	    ret = am_false;
@@ -690,10 +664,10 @@ local_pid_monitor(Process *p, Eterm target, Eterm mon_ref, int boolean)
 	erts_add_monitor(&ERTS_P_MONITORS(p), MON_ORIGIN, mon_ref, target, NIL);
 	erts_add_monitor(&ERTS_P_MONITORS(rp), MON_TARGET, mon_ref, p->common.id, NIL);
 
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
     }
 
-    erts_smp_proc_unlock(p, p_locks & ~ERTS_PROC_LOCK_MAIN);
+    erts_proc_unlock(p, p_locks & ~ERTS_PROC_LOCK_MAIN);
 
     return ret;
 }
@@ -727,7 +701,7 @@ res_no_proc:
             break;
         }
     }
-    erts_smp_proc_unlock(origin, p_locks & ~ERTS_PROC_LOCK_MAIN);
+    erts_proc_unlock(origin, p_locks & ~ERTS_PROC_LOCK_MAIN);
     BIF_RET(ref);
 }
 
@@ -742,7 +716,7 @@ local_name_monitor(Process *self, Eterm type, Eterm target_name)
     Process     *proc = NULL;
     Port        *port = NULL;
 
-    erts_smp_proc_lock(self, ERTS_PROC_LOCK_LINK);
+    erts_proc_lock(self, ERTS_PROC_LOCK_LINK);
 
     erts_whereis_name(self, p_locks, target_name,
                       &proc, ERTS_PROC_LOCK_LINK,
@@ -761,7 +735,7 @@ local_name_monitor(Process *self, Eterm type, Eterm target_name)
 	Eterm item;
         UseTmpHeap(3,self);
 
-        erts_smp_proc_unlock(self, ERTS_PROC_LOCK_LINK);
+        erts_proc_unlock(self, ERTS_PROC_LOCK_LINK);
 	p_locks &= ~ERTS_PROC_LOCK_LINK;
 
 	item = TUPLE2(lhp, target_name, erts_this_dist_entry->sysname);
@@ -772,7 +746,7 @@ local_name_monitor(Process *self, Eterm type, Eterm target_name)
         UnUseTmpHeap(3,self);
     }
     else if (port) {
-        erts_smp_proc_unlock(self, p_locks & ~ERTS_PROC_LOCK_MAIN);
+        erts_proc_unlock(self, p_locks & ~ERTS_PROC_LOCK_MAIN);
         p_locks &= ~ERTS_PROC_LOCK_MAIN;
 
         switch (erts_port_monitor(self, port, target_name, &ret)) {
@@ -793,16 +767,16 @@ local_name_monitor(Process *self, Eterm type, Eterm target_name)
                          proc->common.id, target_name);
         erts_add_monitor(&ERTS_P_MONITORS(proc), MON_TARGET, ret,
                          self->common.id, target_name);
-        erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_LINK);
+        erts_proc_unlock(proc, ERTS_PROC_LOCK_LINK);
     }
 
     if (p_locks) {
-        erts_smp_proc_unlock(self, p_locks & ~ERTS_PROC_LOCK_MAIN);
+        erts_proc_unlock(self, p_locks & ~ERTS_PROC_LOCK_MAIN);
     }
     BIF_RET(ret);
 badarg:
     if (p_locks) {
-        erts_smp_proc_unlock(self, p_locks & ~ERTS_PROC_LOCK_MAIN);
+        erts_proc_unlock(self, p_locks & ~ERTS_PROC_LOCK_MAIN);
     }
     BIF_ERROR(self, BADARG);
 }
@@ -815,23 +789,20 @@ remote_monitor(Process *p, Eterm bifarg1, Eterm bifarg2,
     BIF_RETTYPE ret;
     int code;
 
-    erts_smp_proc_lock(p, ERTS_PROC_LOCK_LINK);
-    code = erts_dsig_prepare(&dsd, dep, p, ERTS_DSP_RLOCK, 0);
+    ASSERT(dep);
+    erts_proc_lock(p, ERTS_PROC_LOCK_LINK);
+    code = erts_dsig_prepare(&dsd, dep,
+			     p, (ERTS_PROC_LOCK_MAIN | ERTS_PROC_LOCK_LINK),
+			     ERTS_DSP_RLOCK, 0, 1);
     switch (code) {
     case ERTS_DSIG_PREP_NOT_ALIVE:
-	/* Let the dmonitor_p trap handle it */
     case ERTS_DSIG_PREP_NOT_CONNECTED:
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(p, ERTS_PROC_LOCK_LINK);
 	ERTS_BIF_PREP_TRAP2(ret, dmonitor_p_trap, p, bifarg1, bifarg2);
 	break;
+    case ERTS_DSIG_PREP_PENDING:
     case ERTS_DSIG_PREP_CONNECTED:
-	if (!(dep->flags & DFLAG_DIST_MONITOR)
-	    || (byname && !(dep->flags & DFLAG_DIST_MONITOR_NAME))) {
-	    erts_smp_de_runlock(dep);
-	    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_LINK);
-	    ERTS_BIF_PREP_ERROR(ret, p, BADARG);
-	}
-	else {
+	{
 	    Eterm p_trgt, p_name, d_name, mon_ref;
 
 	    mon_ref = erts_make_ref(p);
@@ -847,16 +818,16 @@ remote_monitor(Process *p, Eterm bifarg1, Eterm bifarg2,
 		d_name = NIL;
 	    }
 
-	    erts_smp_de_links_lock(dep);
+	    erts_de_links_lock(dep);
 
 	    erts_add_monitor(&ERTS_P_MONITORS(p), MON_ORIGIN, mon_ref, p_trgt,
 			     p_name);
 	    erts_add_monitor(&(dep->monitors), MON_TARGET, mon_ref, p->common.id,
 			     d_name);
 
-	    erts_smp_de_links_unlock(dep);
-	    erts_smp_de_runlock(dep);
-	    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_LINK);
+	    erts_de_links_unlock(dep);
+	    erts_de_runlock(dep);
+	    erts_proc_unlock(p, ERTS_PROC_LOCK_LINK);
 
 	    code = erts_dsig_send_monitor(&dsd, p->common.id, target, mon_ref);
 	    if (code == ERTS_DSIG_SEND_YIELD)
@@ -866,9 +837,7 @@ remote_monitor(Process *p, Eterm bifarg1, Eterm bifarg2,
 	}
 	break;
     default:
-	ASSERT(! "Invalid dsig prepare result");
-	ERTS_BIF_PREP_ERROR(ret, p, EXC_INTERNAL_ERROR);
-	break;
+	ERTS_ASSERT(! "Invalid dsig prepare result");
     }
 
     BIF_RET(ret);
@@ -879,7 +848,6 @@ BIF_RETTYPE monitor_2(BIF_ALIST_2)
     Eterm target = BIF_ARG_2;
     BIF_RETTYPE ret;
     DistEntry  *dep = NULL; 
-    int deref_de = 0;
 
     /* Only process monitors are implemented */
     switch (BIF_ARG_1) {
@@ -889,10 +857,10 @@ BIF_RETTYPE monitor_2(BIF_ALIST_2)
             goto badarg;
         }
 	ref = erts_make_ref(BIF_P);
-	erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK);
+	erts_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK);
 	erts_add_monitor(&ERTS_P_MONITORS(BIF_P), MON_TIME_OFFSET,
 			 ref, am_clock_service, NIL);
-	erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
 	erts_monitor_time_offset(BIF_P->common.id, ref);
 	BIF_RET(ref);
     }
@@ -937,24 +905,17 @@ local_port:
 	if (!erts_is_alive && remote_node != am_Noname) {
             goto badarg; /* Remote monitor from (this) undistributed node */
 	}
-	dep = erts_sysname_to_connected_dist_entry(remote_node);
+	dep = erts_find_or_insert_dist_entry(remote_node);
 	if (dep == erts_this_dist_entry) {
-	    deref_de = 1;
             ret = local_name_monitor(BIF_P, BIF_ARG_1, name);
 	} else {
-	    if (dep)
-		deref_de = 1;
 	    ret = remote_monitor(BIF_P, BIF_ARG_1, BIF_ARG_2, dep, name, 1);
 	}
+	erts_deref_dist_entry(dep);
     } else {
 badarg:
 	ERTS_BIF_PREP_ERROR(ret, BIF_P, BADARG);
     }
-    if (deref_de) {
-	deref_de = 0;
-	erts_deref_dist_entry(dep);
-    }
-
     return ret;
 }
 
@@ -1009,7 +970,7 @@ BIF_RETTYPE spawn_opt_1(BIF_ALIST_1)
     so.max_heap_size  = H_MAX_SIZE;
     so.max_heap_flags = H_MAX_FLAGS;
     so.priority       = PRIORITY_NORMAL;
-    so.max_gen_gcs    = (Uint16) erts_smp_atomic32_read_nob(&erts_max_gen_gcs);
+    so.max_gen_gcs    = (Uint16) erts_atomic32_read_nob(&erts_max_gen_gcs);
     so.scheduler      = 0;
 
     /*
@@ -1150,15 +1111,13 @@ BIF_RETTYPE unlink_1(BIF_ALIST_1)
     }
 
     if (is_internal_port(BIF_ARG_1)) {
-	erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
-#ifdef ERTS_SMP
+	erts_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
 	if (ERTS_PROC_PENDING_EXIT(BIF_P))
 	    goto handle_pending_exit;
-#endif
 
 	l = erts_remove_link(&ERTS_P_LINKS(BIF_P), BIF_ARG_1);
 
-	erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
 
 	if (l) {
 	    Port *prt;
@@ -1200,14 +1159,12 @@ BIF_RETTYPE unlink_1(BIF_ALIST_1)
 	/* Blind removal, we might have trapped or anything, this leaves
 	   us in a state where monitors might be inconsistent, but the dist
 	   code should take care of it. */
-	erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
-#ifdef ERTS_SMP
+	erts_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
 	if (ERTS_PROC_PENDING_EXIT(BIF_P))
 	    goto handle_pending_exit;
-#endif
 	l = erts_remove_link(&ERTS_P_LINKS(BIF_P), BIF_ARG_1);
 
-	erts_smp_proc_unlock(BIF_P,
+	erts_proc_unlock(BIF_P,
 			     ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
 
 	if (l)
@@ -1218,21 +1175,14 @@ BIF_RETTYPE unlink_1(BIF_ALIST_1)
 	    BIF_RET(am_true);
 	}
 
-	code = erts_dsig_prepare(&dsd, dep, BIF_P, ERTS_DSP_NO_LOCK, 0);
+	code = erts_dsig_prepare(&dsd, dep, BIF_P, ERTS_PROC_LOCK_MAIN,
+				 ERTS_DSP_NO_LOCK, 0, 0);
 	switch (code) {
 	case ERTS_DSIG_PREP_NOT_ALIVE:
 	case ERTS_DSIG_PREP_NOT_CONNECTED:
-#if 1
 	    BIF_RET(am_true);
-#else
-	    /*
-	     * This is how we used to do it, but the link is obviously not
-	     * active, so I see no point in setting up a connection.
-	     * /Rickard
-	     */
-	    BIF_TRAP1(dunlink_trap, BIF_P, BIF_ARG_1);
-#endif
 
+	case ERTS_DSIG_PREP_PENDING:
 	case ERTS_DSIG_PREP_CONNECTED:
 	    erts_remove_dist_link(&dld, BIF_P->common.id, BIF_ARG_1, dep);
 	    code = erts_dsig_send_unlink(&dsd, BIF_P->common.id, BIF_ARG_1);
@@ -1249,7 +1199,7 @@ BIF_RETTYPE unlink_1(BIF_ALIST_1)
 
     /* Internal pid... */
 
-    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
+    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
 
     cp_locks |= ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS;
 
@@ -1258,13 +1208,11 @@ BIF_RETTYPE unlink_1(BIF_ALIST_1)
 			   BIF_ARG_1, ERTS_PROC_LOCK_LINK,
 			   ERTS_P2P_FLG_ALLOW_OTHER_X);
 
-#ifdef ERTS_SMP
     if (ERTS_PROC_PENDING_EXIT(BIF_P)) {
 	if (rp && rp != BIF_P)
-	    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	    erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 	goto handle_pending_exit;
     }
-#endif
 
     /* unlink and ignore errors */
     l = erts_remove_link(&ERTS_P_LINKS(BIF_P), BIF_ARG_1);
@@ -1272,7 +1220,7 @@ BIF_RETTYPE unlink_1(BIF_ALIST_1)
 	erts_destroy_link(l);
 
     if (!rp) {
-	ERTS_SMP_ASSERT_IS_NOT_EXITING(BIF_P);
+	ERTS_ASSERT_IS_NOT_EXITING(BIF_P);
     }
     else {
 	rl = erts_remove_link(&ERTS_P_LINKS(rp), BIF_P->common.id);
@@ -1280,29 +1228,27 @@ BIF_RETTYPE unlink_1(BIF_ALIST_1)
 	    erts_destroy_link(rl);
 
 	if (IS_TRACED_FL(rp, F_TRACE_PROCS) && rl != NULL) {
-            erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_STATUS);
+            erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_STATUS);
             cp_locks &= ~ERTS_PROC_LOCK_STATUS;
 	    trace_proc(BIF_P, (ERTS_PROC_LOCK_MAIN | ERTS_PROC_LOCK_LINK),
                        rp, am_getting_unlinked, BIF_P->common.id);
 	}
 
 	if (rp != BIF_P)
-	    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	    erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
     }
  
-    erts_smp_proc_unlock(BIF_P, cp_locks & ~ERTS_PROC_LOCK_MAIN);
+    erts_proc_unlock(BIF_P, cp_locks & ~ERTS_PROC_LOCK_MAIN);
 
     BIF_RET(am_true);
 
-#ifdef ERTS_SMP
  handle_pending_exit:
     erts_handle_pending_exit(BIF_P, (ERTS_PROC_LOCK_MAIN
 				     | ERTS_PROC_LOCK_LINK
 				     | ERTS_PROC_LOCK_STATUS));
     ASSERT(ERTS_PROC_IS_EXITING(BIF_P)); 
-    erts_smp_proc_unlock(BIF_P,	ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
+    erts_proc_unlock(BIF_P,	ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
     ERTS_BIF_EXITED(BIF_P);
-#endif
 }
 
 BIF_RETTYPE hibernate_3(BIF_ALIST_3)
@@ -1314,7 +1260,11 @@ BIF_RETTYPE hibernate_3(BIF_ALIST_3)
      */
     Eterm reg[3];
 
-    if (erts_hibernate(BIF_P, BIF_ARG_1, BIF_ARG_2, BIF_ARG_3, reg)) {
+    reg[0] = BIF_ARG_1;
+    reg[1] = BIF_ARG_2;
+    reg[2] = BIF_ARG_3;
+
+    if (erts_hibernate(BIF_P, reg)) {
         /*
          * If hibernate succeeded, TRAP. The process will be wait in a
          * hibernated state if its state is inactive (!ERTS_PSFLG_ACTIVE);
@@ -1605,22 +1555,24 @@ BIF_RETTYPE exit_2(BIF_ALIST_2)
 	 DistEntry *dep;
 
 	 dep = external_pid_dist_entry(BIF_ARG_1);
+	 ERTS_ASSERT(dep);
 	 if(dep == erts_this_dist_entry)
 	     BIF_RET(am_true);
 
-	 code = erts_dsig_prepare(&dsd, dep, BIF_P, ERTS_DSP_NO_LOCK, 0);
+	 code = erts_dsig_prepare(&dsd, dep, BIF_P, ERTS_PROC_LOCK_MAIN,
+				  ERTS_DSP_NO_LOCK, 0, 1);
 	 switch (code) {
 	 case ERTS_DSIG_PREP_NOT_ALIVE:
 	 case ERTS_DSIG_PREP_NOT_CONNECTED:
-	     BIF_TRAP2(dexit_trap, BIF_P, BIF_ARG_1, BIF_ARG_2);
+	     BIF_RET(am_true);
+	 case ERTS_DSIG_PREP_PENDING:
 	 case ERTS_DSIG_PREP_CONNECTED:
 	     code = erts_dsig_send_exit2(&dsd, BIF_P->common.id, BIF_ARG_1, BIF_ARG_2);
 	     if (code == ERTS_DSIG_SEND_YIELD)
 		 ERTS_BIF_YIELD_RETURN(BIF_P, am_true);
 	     BIF_RET(am_true);
 	 default:
-	     ASSERT(! "Invalid dsig prepare result");
-	     BIF_ERROR(BIF_P, EXC_INTERNAL_ERROR);
+	     ERTS_ASSERT(! "Invalid dsig prepare result");
 	 }
      }
      else if (is_not_internal_pid(BIF_ARG_1)) {
@@ -1635,7 +1587,7 @@ BIF_RETTYPE exit_2(BIF_ALIST_2)
 	 if (BIF_ARG_1 == BIF_P->common.id) {
 	     rp_locks = ERTS_PROC_LOCKS_ALL;
 	     rp = BIF_P;
-	     erts_smp_proc_lock(rp, ERTS_PROC_LOCKS_ALL_MINOR);
+	     erts_proc_lock(rp, ERTS_PROC_LOCKS_ALL_MINOR);
 	 }
 	 else {
 	     rp_locks = ERTS_PROC_LOCKS_XSIG_SEND;
@@ -1657,12 +1609,10 @@ BIF_RETTYPE exit_2(BIF_ALIST_2)
 			       NIL,
 			       NULL,
 			       BIF_P == rp ? ERTS_XSIG_FLG_NO_IGN_NORMAL : 0);
-#ifdef ERTS_SMP
 	 if (rp == BIF_P)
 	     rp_locks &= ~ERTS_PROC_LOCK_MAIN;
 	 if (rp_locks)
-	     erts_smp_proc_unlock(rp, rp_locks);
-#endif
+	     erts_proc_unlock(rp, rp_locks);
 	 /*
 	  * We may have exited ourselves and may have to take action.
 	  */
@@ -1774,21 +1724,19 @@ BIF_RETTYPE process_flag_2(BIF_ALIST_2)
 	*       true. For more info, see implementation of
 	*       erts_send_exit_signal().
 	*/
-       erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCKS_XSIG_SEND);
+       erts_proc_lock(BIF_P, ERTS_PROC_LOCKS_XSIG_SEND);
        if (trap_exit)
-	   state = erts_smp_atomic32_read_bor_mb(&BIF_P->state,
+	   state = erts_atomic32_read_bor_mb(&BIF_P->state,
 						 ERTS_PSFLG_TRAP_EXIT);
        else
-	   state = erts_smp_atomic32_read_band_mb(&BIF_P->state,
+	   state = erts_atomic32_read_band_mb(&BIF_P->state,
 						  ~ERTS_PSFLG_TRAP_EXIT);
-       erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCKS_XSIG_SEND);
+       erts_proc_unlock(BIF_P, ERTS_PROC_LOCKS_XSIG_SEND);
 
-#ifdef ERTS_SMP
        if (state & ERTS_PSFLG_PENDING_EXIT) {
 	   erts_handle_pending_exit(BIF_P, ERTS_PROC_LOCK_MAIN);
 	   ERTS_BIF_EXITED(BIF_P);
        }
-#endif
 
        old_value = (state & ERTS_PSFLG_TRAP_EXIT) ? am_true : am_false;
        BIF_RET(old_value);
@@ -1806,15 +1754,13 @@ BIF_RETTYPE process_flag_2(BIF_ALIST_2)
 
        if (sched == 0) {
 	   new = NULL;
-	   state = erts_smp_atomic32_read_band_mb(&BIF_P->state,
+	   state = erts_atomic32_read_band_mb(&BIF_P->state,
 						  ~ERTS_PSFLG_BOUND);
        }
        else {
 	   new = erts_schedid2runq(sched);
-#ifdef ERTS_SMP
 	   erts_atomic_set_nob(&BIF_P->run_queue, (erts_aint_t) new);
-#endif
-	   state = erts_smp_atomic32_read_bor_mb(&BIF_P->state,
+	   state = erts_atomic32_read_bor_mb(&BIF_P->state,
 						 ERTS_PSFLG_BOUND);
        }
 
@@ -1895,7 +1841,7 @@ BIF_RETTYPE process_flag_2(BIF_ALIST_2)
        } else {
 	   goto error;
        }
-       erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCKS_ALL_MINOR);
+       erts_proc_lock(BIF_P, ERTS_PROC_LOCKS_ALL_MINOR);
        old_value = (ERTS_TRACE_FLAGS(BIF_P) & F_SENSITIVE
 		    ? am_true
 		    : am_false);
@@ -1904,7 +1850,7 @@ BIF_RETTYPE process_flag_2(BIF_ALIST_2)
        } else {
 	   ERTS_TRACE_FLAGS(BIF_P) &= ~F_SENSITIVE;
        }
-       erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCKS_ALL_MINOR);
+       erts_proc_unlock(BIF_P, ERTS_PROC_LOCKS_ALL_MINOR);
        /* make sure to bump all reds so that we get
           rescheduled immediately so setting takes effect */
        BIF_RET2(old_value, CONTEXT_REDS);
@@ -1946,15 +1892,11 @@ BIF_RETTYPE process_flag_3(BIF_ALIST_3)
    Process *rp;
    Eterm res;
 
-#ifdef ERTS_SMP
    rp = erts_pid2proc_not_running(BIF_P, ERTS_PROC_LOCK_MAIN,
 				  BIF_ARG_1, ERTS_PROC_LOCK_MAIN);
    if (rp == ERTS_PROC_LOCK_BUSY)
        ERTS_BIF_YIELD3(bif_export[BIF_process_flag_3], BIF_P,
 		       BIF_ARG_1, BIF_ARG_2, BIF_ARG_3);
-#else
-   rp = erts_proc_lookup(BIF_ARG_1);
-#endif
 
    if (!rp)
        BIF_ERROR(BIF_P, BADARG);
@@ -1962,7 +1904,7 @@ BIF_RETTYPE process_flag_3(BIF_ALIST_3)
    res = process_flag_aux(BIF_P, rp, BIF_ARG_2, BIF_ARG_3);
 
    if (rp != BIF_P)
-       erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_MAIN);
+       erts_proc_unlock(rp, ERTS_PROC_LOCK_MAIN);
 
    return res;
 }
@@ -2034,7 +1976,7 @@ ebif_bang_2(BIF_ALIST_2)
  * Send a message to Process, Port or Registered Process.
  * Returns non-negative reduction bump or negative result code.
  */
-#define SEND_TRAP		(-1)
+#define SEND_NOCONNECT		(-1)
 #define SEND_YIELD		(-2)
 #define SEND_YIELD_RETURN	(-3)
 #define SEND_BADARG		(-4)
@@ -2050,19 +1992,22 @@ static Sint remote_send(Process *p, DistEntry *dep,
 {
     Sint res;
     int code;
-
     ASSERT(is_atom(to) || is_external_pid(to));
 
-    code = erts_dsig_prepare(&ctx->dsd, dep, p, ERTS_DSP_NO_LOCK, !ctx->suspend);
+    ctx->dep = dep;
+    code = erts_dsig_prepare(&ctx->dsd, dep, p, ERTS_PROC_LOCK_MAIN,
+			     ERTS_DSP_NO_LOCK,
+			     !ctx->suspend, ctx->connect);
     switch (code) {
     case ERTS_DSIG_PREP_NOT_ALIVE:
     case ERTS_DSIG_PREP_NOT_CONNECTED:
-	res = SEND_TRAP;
+	res = SEND_NOCONNECT;
 	break;
     case ERTS_DSIG_PREP_WOULD_SUSPEND:
 	ASSERT(!ctx->suspend);
 	res = SEND_YIELD;
 	break;
+    case ERTS_DSIG_PREP_PENDING:
     case ERTS_DSIG_PREP_CONNECTED: {
 
 	if (is_atom(to))
@@ -2239,6 +2184,7 @@ do_send(Process *p, Eterm to, Eterm msg, Eterm *refp, ErtsSendContext *ctx)
 	}
 	return ret_val;
     } else if (is_tuple(to)) { /* Remote send */
+        int deref_dep = 0;
 	int ret;
 	tp = tuple_val(to);
 	if (*tp != make_arityval(2))
@@ -2246,15 +2192,13 @@ do_send(Process *p, Eterm to, Eterm msg, Eterm *refp, ErtsSendContext *ctx)
 	if (is_not_atom(tp[1]) || is_not_atom(tp[2]))
 	    return SEND_BADARG;
 	
-	/* sysname_to_connected_dist_entry will return NULL if there
-	   is no dist_entry or the dist_entry has no port,
+	/* erts_find_dist_entry will return NULL if there is no dist_entry
 	   but remote_send() will handle that. */
 
-	dep = erts_sysname_to_connected_dist_entry(tp[2]);
+	dep = erts_find_dist_entry(tp[2]);
 
 	if (dep == erts_this_dist_entry) {
 	    Eterm id;
-	    erts_deref_dist_entry(dep);
 	    if (IS_TRACED_FL(p, F_TRACE_SEND))
 		trace_send(p, to, msg);
 	    if (ERTS_PROC_GET_SAVED_CALLS_BUF(p))
@@ -2275,15 +2219,20 @@ do_send(Process *p, Eterm to, Eterm msg, Eterm *refp, ErtsSendContext *ctx)
 	    }
 	    return 0;
 	}
+        if (dep == NULL) {
+            dep = erts_find_or_insert_dist_entry(tp[2]);
+            ASSERT(dep != erts_this_dist_entry);
+            deref_dep = 1;
+        }
+	ctx->dsd.node = tp[2];
 
 	ret = remote_send(p, dep, tp[1], to, msg, ctx);
-	if (ret != SEND_YIELD_CONTINUE) {
-	    if (dep) {
-		erts_deref_dist_entry(dep);
-	    }
-	} else {
-	    ctx->dep_to_deref = dep;
+	if (ret == SEND_YIELD_CONTINUE) {
+            erts_ref_dist_entry(ctx->dep);
+            ctx->deref_dep = 1;
 	}
+        if (deref_dep)
+            erts_deref_dist_entry(dep);
 	return ret;
     } else {
 	if (IS_TRACED_FL(p, F_TRACE_SEND))
@@ -2296,17 +2245,15 @@ do_send(Process *p, Eterm to, Eterm msg, Eterm *refp, ErtsSendContext *ctx)
  send_message: {
 	ErtsProcLocks rp_locks = 0;
 	Sint res;
-#ifdef ERTS_SMP
 	if (p == rp)
 	    rp_locks |= ERTS_PROC_LOCK_MAIN;
-#endif
 	/* send to local process */
 	res = erts_send_message(p, rp, &rp_locks, msg, 0);
 	if (erts_use_sender_punish)
 	    res *= 4;
 	else
 	    res = 0;
-	erts_smp_proc_unlock(rp,
+	erts_proc_unlock(rp,
 			     p == rp
 			     ? (rp_locks & ~ERTS_PROC_LOCK_MAIN)
 			     : rp_locks);
@@ -2325,7 +2272,6 @@ BIF_RETTYPE send_3(BIF_ALIST_3)
     Eterm msg = BIF_ARG_2;
     Eterm opts = BIF_ARG_3;
 
-    int connect = !0;
     Eterm l = opts;
     Sint result;
 
@@ -2336,14 +2282,15 @@ BIF_RETTYPE send_3(BIF_ALIST_3)
     UseTmpHeap(sizeof(ErtsSendContext)/sizeof(Eterm), BIF_P);
 
     ctx->suspend = !0;
-    ctx->dep_to_deref = NULL;
+    ctx->connect = !0;
+    ctx->deref_dep = 0;
     ctx->return_term = am_ok;
     ctx->dss.reds = (Sint) (ERTS_BIF_REDS_LEFT(p) * TERM_TO_BINARY_LOOP_FACTOR);
     ctx->dss.phase = ERTS_DSIG_SEND_PHASE_INIT;
 
     while (is_list(l)) {
 	if (CAR(list_val(l)) == am_noconnect) {
-	    connect = 0;
+	    ctx->connect = 0;
 	} else if (CAR(list_val(l)) == am_nosuspend) {
 	    ctx->suspend = 0;
 	} else {
@@ -2380,9 +2327,9 @@ BIF_RETTYPE send_3(BIF_ALIST_3)
 	    goto yield_return;
 	ERTS_BIF_PREP_RET(retval, am_ok);
 	break;
-    case SEND_TRAP:
-	if (connect) {
-	    ERTS_BIF_PREP_TRAP3(retval, dsend3_trap, p, to, msg, opts);
+    case SEND_NOCONNECT:
+	if (ctx->connect) {
+	    ERTS_BIF_PREP_RET(retval, am_ok);
 	} else {
 	    ERTS_BIF_PREP_RET(retval, am_noconnect);
 	}
@@ -2486,7 +2433,8 @@ Eterm erl_send(Process *p, Eterm to, Eterm msg)
     ref = NIL;
 #endif
     ctx->suspend = !0;
-    ctx->dep_to_deref = NULL;
+    ctx->connect = !0;
+    ctx->deref_dep = 0;
     ctx->return_term = msg;
     ctx->dss.reds = (Sint) (ERTS_BIF_REDS_LEFT(p) * TERM_TO_BINARY_LOOP_FACTOR);
     ctx->dss.phase = ERTS_DSIG_SEND_PHASE_INIT;
@@ -2510,8 +2458,8 @@ Eterm erl_send(Process *p, Eterm to, Eterm msg)
 	    goto yield_return;
 	ERTS_BIF_PREP_RET(retval, msg);
 	break;
-    case SEND_TRAP:
-	ERTS_BIF_PREP_TRAP2(retval, dsend2_trap, p, to, msg);
+    case SEND_NOCONNECT:
+	ERTS_BIF_PREP_RET(retval, msg);
 	break;
     case SEND_YIELD:
 	ERTS_BIF_PREP_YIELD2(retval, bif_export[BIF_send_2], p, to, msg);
@@ -4010,14 +3958,14 @@ BIF_RETTYPE halt_2(BIF_ALIST_2)
 	    ERTS_BIF_YIELD2(bif_export[BIF_halt_2], BIF_P, am_undefined, am_undefined);
 	}
 	else {
-	    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
             erts_exit(pos_int_code, "");
 	}
     }
     else if (ERTS_IS_ATOM_STR("abort", BIF_ARG_1)) {
 	VERBOSE(DEBUG_SYSTEM,
 		("System halted by BIF halt(%T, %T)\n", BIF_ARG_1, BIF_ARG_2));
-	erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
 	erts_exit(ERTS_ABORT_EXIT, "");
     }
     else if (is_list(BIF_ARG_1) || BIF_ARG_1 == NIL) {
@@ -4033,7 +3981,7 @@ BIF_RETTYPE halt_2(BIF_ALIST_2)
 	halt_msg[written] = '\0';
 	VERBOSE(DEBUG_SYSTEM,
 		("System halted by BIF halt(%T, %T)\n", BIF_ARG_1, BIF_ARG_2));
-	erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
 	erts_exit(ERTS_DUMP_EXIT, "%s\n", halt_msg);
     }
     else
@@ -4219,7 +4167,6 @@ BIF_RETTYPE list_to_pid_1(BIF_ALIST_1)
 	goto bad;
 
     if(dep == erts_this_dist_entry) {
-	erts_deref_dist_entry(dep);
 	BIF_RET(make_internal_pid(make_pid_data(c, b)));
     }
     else {
@@ -4239,13 +4186,10 @@ BIF_RETTYPE list_to_pid_1(BIF_ALIST_1)
       etp->data.ui[0] = make_pid_data(c, b);
 
       MSO(BIF_P).first = (struct erl_off_heap_header*) etp;
-      erts_deref_dist_entry(dep);
       BIF_RET(make_external_pid(etp));
     }
 
  bad:
-    if (dep)
-	erts_deref_dist_entry(dep);
     if (buf)
 	erts_free(ERTS_ALC_T_TMP, (void *) buf);
     BIF_ERROR(BIF_P, BADARG);
@@ -4278,7 +4222,7 @@ BIF_RETTYPE list_to_port_1(BIF_ALIST_1)
 
     cp += 6; /* strlen("#Port<") */
 
-    if (sscanf(cp, "%u.%u>", &n, &p) < 2)
+    if (sscanf(cp, "%u.%u>", (unsigned int*)&n, (unsigned int*)&p) < 2)
         goto bad;
 
     if (p > ERTS_MAX_PORT_NUMBER)
@@ -4290,7 +4234,6 @@ BIF_RETTYPE list_to_port_1(BIF_ALIST_1)
 	goto bad;
 
     if(dep == erts_this_dist_entry) {
-	erts_deref_dist_entry(dep);
 	BIF_RET(make_internal_port(p));
     }
     else {
@@ -4310,13 +4253,10 @@ BIF_RETTYPE list_to_port_1(BIF_ALIST_1)
       etp->data.ui[0] = p;
 
       MSO(BIF_P).first = (struct erl_off_heap_header*) etp;
-      erts_deref_dist_entry(dep);
       BIF_RET(make_external_port(etp));
     }
 
  bad:
-    if (dep)
-	erts_deref_dist_entry(dep);
     BIF_ERROR(BIF_P, BADARG);
 }
 
@@ -4436,12 +4376,9 @@ BIF_RETTYPE list_to_ref_1(BIF_ALIST_1)
       res = make_external_ref(etp);
     }
 
-    erts_deref_dist_entry(dep);
     BIF_RET(res);
 
  bad:
-    if (dep)
-	erts_deref_dist_entry(dep);
     BIF_ERROR(BIF_P, BADARG);
 }
 
@@ -4469,23 +4406,24 @@ BIF_RETTYPE group_leader_2(BIF_ALIST_2)
 	int code;
 	ErtsDSigData dsd;
 	dep = external_pid_dist_entry(BIF_ARG_2);
+	ERTS_ASSERT(dep);
 	if(dep == erts_this_dist_entry)
 	    BIF_ERROR(BIF_P, BADARG);
 
-	code = erts_dsig_prepare(&dsd, dep, BIF_P, ERTS_DSP_NO_LOCK, 0);
+	code = erts_dsig_prepare(&dsd, dep, BIF_P, ERTS_PROC_LOCK_MAIN,
+				 ERTS_DSP_NO_LOCK, 0, 1);
 	switch (code) {
 	case ERTS_DSIG_PREP_NOT_ALIVE:
-	    BIF_RET(am_true);
 	case ERTS_DSIG_PREP_NOT_CONNECTED:
-	    BIF_TRAP2(dgroup_leader_trap, BIF_P, BIF_ARG_1, BIF_ARG_2);
+	    BIF_RET(am_true);
+	case ERTS_DSIG_PREP_PENDING:
 	case ERTS_DSIG_PREP_CONNECTED:
 	    code = erts_dsig_send_group_leader(&dsd, BIF_ARG_1, BIF_ARG_2);
 	    if (code == ERTS_DSIG_SEND_YIELD)
 		ERTS_BIF_YIELD_RETURN(BIF_P, am_true);
 	    BIF_RET(am_true);
 	default:
-	    ASSERT(! "Invalid dsig prepare result");
-	    BIF_ERROR(BIF_P, EXC_INTERNAL_ERROR);
+	    ERTS_ASSERT(! "Invalid dsig prepare result");
 	}
     }
     else if (is_internal_pid(BIF_ARG_2)) {
@@ -4507,9 +4445,9 @@ BIF_RETTYPE group_leader_2(BIF_ALIST_2)
 		new_member->group_leader = BIF_ARG_1;
 	    else {
 		locks &= ~ERTS_PROC_LOCK_STATUS;
-		erts_smp_proc_unlock(new_member, ERTS_PROC_LOCK_STATUS);
+		erts_proc_unlock(new_member, ERTS_PROC_LOCK_STATUS);
 		if (new_member == BIF_P
-		    || !(erts_smp_atomic32_read_nob(&new_member->state)
+		    || !(erts_atomic32_read_nob(&new_member->state)
 			 & ERTS_PSFLG_DIRTY_RUNNING)) {
 		    new_member->group_leader = STORE_NC_IN_PROC(new_member,
 								BIF_ARG_1);
@@ -4538,7 +4476,7 @@ BIF_RETTYPE group_leader_2(BIF_ALIST_2)
 	if (new_member == BIF_P)
 	    locks &= ~ERTS_PROC_LOCK_MAIN;
 	if (locks)
-	    erts_smp_proc_unlock(new_member, locks);
+	    erts_proc_unlock(new_member, locks);
 
 	if (await_x) {
 	    /* Wait for new_member to terminate; then badarg */
@@ -4557,7 +4495,7 @@ BIF_RETTYPE group_leader_2(BIF_ALIST_2)
 	BIF_ERROR(BIF_P, BADARG);
     }
 }
-    
+
 BIF_RETTYPE system_flag_2(BIF_ALIST_2)    
 {
     Sint n;
@@ -4565,9 +4503,6 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
     if (BIF_ARG_1 == am_multi_scheduling) {
 	if (BIF_ARG_2 == am_block || BIF_ARG_2 == am_unblock
 	    || BIF_ARG_2 == am_block_normal || BIF_ARG_2 == am_unblock_normal) {
-#ifndef ERTS_SMP
-	    BIF_RET(am_disabled);
-#else
 	    int block = (BIF_ARG_2 == am_block
 			 || BIF_ARG_2 == am_block_normal);
 	    int normal = (BIF_ARG_2 == am_block_normal
@@ -4603,15 +4538,8 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
                 BIF_ERROR(BIF_P, EXC_INTERNAL_ERROR);
                 break;
             }
-#endif
 	}
     } else if (BIF_ARG_1 == am_schedulers_online) {
-#ifndef ERTS_SMP
-	if (BIF_ARG_2 != make_small(1))
-	    goto error;
-	else
-	    BIF_RET(make_small(1));
-#else
 	Sint old_no;
 	if (!is_small(BIF_ARG_2))
 	    goto error;
@@ -4635,7 +4563,6 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
 	    BIF_ERROR(BIF_P, EXC_INTERNAL_ERROR);
 	    break;
 	}
-#endif
     } else if (BIF_ARG_1 == am_fullsweep_after) {
 	Uint16 nval;
 	Uint oval;
@@ -4643,7 +4570,7 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
 	    goto error;
 	}
 	nval = (n > (Sint) ((Uint16) -1)) ? ((Uint16) -1) : ((Uint16) n);
-	oval = (Uint) erts_smp_atomic32_xchg_nob(&erts_max_gen_gcs,
+	oval = (Uint) erts_atomic32_xchg_nob(&erts_max_gen_gcs,
 						 (erts_aint32_t) nval);
 	BIF_RET(make_small(oval));
     } else if (BIF_ARG_1 == am_min_heap_size) {
@@ -4653,13 +4580,13 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
 	    goto error;
 	}
 
-	erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-	erts_smp_thr_progress_block();
+	erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_block();
 
 	H_MIN_SIZE = erts_next_heap_size(n, 0);
 
-	erts_smp_thr_progress_unblock();
-	erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_unblock();
+	erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 
 	BIF_RET(make_small(oval));
     } else if (BIF_ARG_1 == am_min_bin_vheap_size) {
@@ -4669,13 +4596,13 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
 	    goto error;
 	}
 
-	erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-	erts_smp_thr_progress_block();
+	erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_block();
 
 	BIN_VH_MIN_SIZE = erts_next_heap_size(n, 0);
 
-	erts_smp_thr_progress_unblock();
-	erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_unblock();
+	erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 
 	BIF_RET(make_small(oval));
     } else if (BIF_ARG_1 == am_max_heap_size) {
@@ -4693,14 +4620,14 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
         hp = HAlloc(BIF_P, sz);
         old_value = erts_max_heap_size_map(H_MAX_SIZE, H_MAX_FLAGS, &hp, NULL);
 
-        erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-        erts_smp_thr_progress_block();
+        erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+        erts_thr_progress_block();
 
         H_MAX_SIZE = max_heap_size;
         H_MAX_FLAGS = max_heap_flags;
 
-        erts_smp_thr_progress_unblock();
-        erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+        erts_thr_progress_unblock();
+        erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 
         BIF_RET(old_value);
     } else if (BIF_ARG_1 == am_display_items) {
@@ -4754,8 +4681,8 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
     } else if (BIF_ARG_1 == make_small(1)) {
 	int i, max;
 	ErtsMessage* mp;
-	erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-	erts_smp_thr_progress_block();
+	erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_block();
 
 	max = erts_ptab_max(&erts_proc);
 	for (i = 0; i < max; i++) {
@@ -4768,7 +4695,7 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
 #endif
 		p->seq_trace_clock = 0;
 		p->seq_trace_lastcnt = 0;
-		ERTS_SMP_MSGQ_MV_INQ2PRIVQ(p);
+		ERTS_MSGQ_MV_INQ2PRIVQ(p);
 		mp = p->msg.first;
 		while(mp != NULL) {
 #ifdef USE_VM_PROBES
@@ -4781,23 +4708,14 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
 	    }
 	}
 
-	erts_smp_thr_progress_unblock();
-	erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_unblock();
+	erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 
 	BIF_RET(am_true);
     } else if (BIF_ARG_1 == am_scheduler_wall_time) {
-	if (BIF_ARG_2 == am_true || BIF_ARG_2 == am_false) {
-	    erts_aint32_t new = BIF_ARG_2 == am_true ? 1 : 0;
-	    erts_aint32_t old = erts_smp_atomic32_xchg_nob(&sched_wall_time,
-							   new);
-	    Eterm ref = erts_sched_wall_time_request(BIF_P, 1, new, 0, 0);
-	    ASSERT(is_value(ref));
-	    BIF_TRAP2(await_sched_wall_time_mod_trap,
-		      BIF_P,
-		      ref,
-		      old ? am_true : am_false);
-	}
-#if defined(ERTS_SMP) && defined(ERTS_DIRTY_SCHEDULERS)
+	if (BIF_ARG_2 == am_true || BIF_ARG_2 == am_false)
+            BIF_TRAP1(system_flag_scheduler_wall_time_trap,
+                      BIF_P, BIF_ARG_2);
     } else if (BIF_ARG_1 == am_dirty_cpu_schedulers_online) {
 	Sint old_no;
 	if (!is_small(BIF_ARG_2))
@@ -4823,13 +4741,12 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
 	    BIF_ERROR(BIF_P, EXC_INTERNAL_ERROR);
 	    break;
 	}
-#endif
     } else if (BIF_ARG_1 == am_time_offset
 	       && ERTS_IS_ATOM_STR("finalize", BIF_ARG_2)) {
 	ErtsTimeOffsetState res;
-	erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
 	res = erts_finalize_time_offset();
-        erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+        erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 	switch (res) {
 	case ERTS_TIME_OFFSET_PRELIMINARY: {
 	    DECL_AM(preliminary);
@@ -4851,7 +4768,7 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
       Eterm threads;
       if (BIF_ARG_2 == am_true || BIF_ARG_2 == am_false) {
         erts_aint32_t new = BIF_ARG_2 == am_true ? ERTS_MSACC_ENABLE : ERTS_MSACC_DISABLE;
-	erts_aint32_t old = erts_smp_atomic32_xchg_nob(&msacc, new);
+	erts_aint32_t old = erts_atomic32_xchg_nob(&msacc, new);
 	Eterm ref = erts_msacc_request(BIF_P, new, &threads);
         if (is_non_value(ref))
             BIF_RET(old ? am_true : am_false);
@@ -4862,7 +4779,7 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
 		  threads);
       } else if (BIF_ARG_2 == am_reset) {
 	Eterm ref = erts_msacc_request(BIF_P, ERTS_MSACC_RESET, &threads);
-	erts_aint32_t old = erts_smp_atomic32_read_nob(&msacc);
+	erts_aint32_t old = erts_atomic32_read_nob(&msacc);
 	ASSERT(is_value(ref));
 	BIF_TRAP3(await_msacc_mod_trap,
 		  BIF_P,
@@ -4881,9 +4798,9 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
 	    what = ERTS_SCHED_STAT_MODIFY_CLEAR;
 	else
 	    goto error;
-	erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
 	erts_sched_stat_modify(what);
-	erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 	BIF_RET(am_true);
     } else if (ERTS_IS_ATOM_STR("internal_cpu_topology", BIF_ARG_1)) {
 	Eterm res = erts_set_cpu_topology(BIF_P, BIF_ARG_2);
@@ -4910,6 +4827,17 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
     BIF_ERROR(BIF_P, BADARG);
 }
 
+BIF_RETTYPE erts_internal_scheduler_wall_time_1(BIF_ALIST_1)
+{
+    erts_aint32_t new = BIF_ARG_1 == am_true ? 1 : 0;
+    erts_aint32_t old = erts_atomic32_xchg_nob(&sched_wall_time,
+                                               new);
+    Eterm ref = erts_sched_wall_time_request(BIF_P, 1, new, 0, 0);
+    ASSERT(is_value(ref));
+    BIF_TRAP2(await_sched_wall_time_mod_trap,
+              BIF_P, ref, old ? am_true : am_false);
+}
+
 /**********************************************************************/
 
 BIF_RETTYPE phash_2(BIF_ALIST_2)
@@ -5021,7 +4949,6 @@ static BIF_RETTYPE bif_return_trap(BIF_ALIST_2)
     Eterm res = BIF_ARG_1;
 
     switch (BIF_ARG_2) {
-#ifdef ERTS_SMP
     case am_multi_scheduling: {
 	int msb = erts_is_multi_scheduling_blocked();
 	if (msb > 0)
@@ -5032,7 +4959,6 @@ static BIF_RETTYPE bif_return_trap(BIF_ALIST_2)
 	    ERTS_INTERNAL_ERROR("Unexpected multi scheduling block state");
 	break;
     }
-#endif
     default:
 	break;
     }
@@ -5057,22 +4983,22 @@ static ERTS_INLINE int
 skip_current_msgq(Process *c_p)
 {
     int res;
-#if defined(ERTS_ENABLE_LOCK_CHECK) && defined(ERTS_SMP)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     erts_proc_lc_chk_only_proc_main(c_p);
 #endif
 
-    erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+    erts_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
     if (ERTS_PROC_PENDING_EXIT(c_p)) {
 	KILL_CATCHES(c_p);
 	c_p->freason = EXC_EXIT;
 	res = 0;
     }
     else {
-        ERTS_SMP_MSGQ_MV_INQ2PRIVQ(c_p);
+        ERTS_MSGQ_MV_INQ2PRIVQ(c_p);
 	c_p->msg.save = c_p->msg.last;
 	res = 1;
     }
-    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+    erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
     return res;
 }
 
@@ -5131,7 +5057,7 @@ void erts_init_trap_export(Export* ep, Eterm m, Eterm f, Uint a,
     ep->info.mfa.module = m;
     ep->info.mfa.function = f;
     ep->info.mfa.arity = a;
-    ep->beam[0] = (BeamInstr) em_apply_bif;
+    ep->beam[0] = BeamOpCodeAddr(op_apply_bif);
     ep->beam[1] = (BeamInstr) bif;
 }
 
@@ -5170,13 +5096,15 @@ void erts_init_bif(void)
     await_proc_exit_trap = erts_export_put(am_erlang,am_await_proc_exit,3);
     await_port_send_result_trap
 	= erts_export_put(am_erts_internal, am_await_port_send_result, 3);
+    system_flag_scheduler_wall_time_trap
+        = erts_export_put(am_erts_internal, am_system_flag_scheduler_wall_time, 1);
     await_sched_wall_time_mod_trap
-        = erts_export_put(am_erlang, am_await_sched_wall_time_modifications, 2);
+        = erts_export_put(am_erts_internal, am_await_sched_wall_time_modifications, 2);
     await_msacc_mod_trap
 	= erts_export_put(am_erts_internal, am_await_microstate_accounting_modifications, 3);
 
-    erts_smp_atomic32_init_nob(&sched_wall_time, 0);
-    erts_smp_atomic32_init_nob(&msacc, ERTS_MSACC_IS_ENABLED());
+    erts_atomic32_init_nob(&sched_wall_time, 0);
+    erts_atomic32_init_nob(&msacc, ERTS_MSACC_IS_ENABLED());
 }
 
 /*
@@ -5194,15 +5122,14 @@ schedule(Process *c_p, Process *dirty_shadow_proc,
 	 Eterm module, Eterm function,
 	 int argc, Eterm *argv)
 {
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(c_p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(c_p));
     (void) erts_nif_export_schedule(c_p, dirty_shadow_proc,
-				    mfa, pc, (BeamInstr) em_apply_bif,
+				    mfa, pc, BeamOpCodeAddr(op_apply_bif),
 				    dfunc, ifunc,
 				    module, function,
 				    argc, argv);
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 static BIF_RETTYPE dirty_bif_result(BIF_ALIST_1)
 {
@@ -5245,9 +5172,7 @@ static BIF_RETTYPE dirty_bif_exception(BIF_ALIST_2)
     BIF_ERROR(BIF_P, freason);
 }
 
-#endif /* ERTS_DIRTY_SCHEDULERS */
 
-extern BeamInstr* em_call_bif_e;
 static BIF_RETTYPE call_bif(Process *c_p, Eterm *reg, BeamInstr *I);
 
 BIF_RETTYPE
@@ -5263,15 +5188,13 @@ erts_schedule_bif(Process *proc,
     Process *c_p, *dirty_shadow_proc;
     ErtsCodeMFA *mfa;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (proc->static_flags & ERTS_STC_FLG_SHADOW_PROC) {
 	dirty_shadow_proc = proc;
 	c_p = proc->next;
 	ASSERT(c_p->common.id == dirty_shadow_proc->common.id);
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+	erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
     }
     else
-#endif
     {
 	dirty_shadow_proc = NULL;
 	c_p = proc;
@@ -5287,7 +5210,6 @@ erts_schedule_bif(Process *proc,
 	 * ibif - indirect bif
 	 */
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 	erts_aint32_t set, mask;
 	mask = (ERTS_PSFLG_DIRTY_CPU_PROC
 		| ERTS_PSFLG_DIRTY_IO_PROC);
@@ -5310,11 +5232,7 @@ erts_schedule_bif(Process *proc,
 	    break;
 	}
 
-	(void) erts_smp_atomic32_read_bset_nob(&c_p->state, mask, set);
-#else
-	dbif = call_bif;
-	ibif = bif;
-#endif
+	(void) erts_atomic32_read_bset_nob(&c_p->state, mask, set);
 
 	if (i == NULL) {
 	    ERTS_INTERNAL_ERROR("Missing instruction pointer");
@@ -5327,13 +5245,13 @@ erts_schedule_bif(Process *proc,
 	    mfa = &exp->info.mfa;
 	}
 #endif
-	else if (em_call_bif_e == (BeamInstr *) *i) {
+	else if (BeamIsOpCode(*i, op_call_bif_e)) {
 	    /* Pointer to bif export in i+1 */
 	    exp = (Export *) i[1];
 	    pc = i;
 	    mfa = &exp->info.mfa;
 	}
-	else if (em_apply_bif == (BeamInstr *) *i) {
+	else if (BeamIsOpCode(*i, op_apply_bif)) {
 	    /* Pointer to bif in i+1, and mfa in i-3 */	    
 	    pc = c_p->cp;
 	    mfa = erts_code_to_codemfa(i);
@@ -5355,7 +5273,7 @@ erts_schedule_bif(Process *proc,
     }
 
     if (dirty_shadow_proc)
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
 
     return THE_NON_VALUE;
 }
@@ -5390,7 +5308,6 @@ call_bif(Process *c_p, Eterm *reg, BeamInstr *I)
     return ret;
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 int
 erts_call_dirty_bif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *reg)
@@ -5405,7 +5322,7 @@ erts_call_dirty_bif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
     erts_aint32_t state;
 
     ASSERT(!c_p->scheduler_data);
-    state = erts_smp_atomic32_read_nob(&c_p->state);
+    state = erts_atomic32_read_nob(&c_p->state);
     ASSERT((state & ERTS_PSFLG_DIRTY_RUNNING)
 	   && !(state & (ERTS_PSFLG_RUNNING|ERTS_PSFLG_RUNNING_SYS)));
     ASSERT(esdp);
@@ -5419,7 +5336,7 @@ erts_call_dirty_bif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
 
     bf = (ErtsBifFunc) I[1];
 
-    erts_smp_atomic32_read_band_mb(&c_p->state, ~(ERTS_PSFLG_DIRTY_CPU_PROC
+    erts_atomic32_read_band_mb(&c_p->state, ~(ERTS_PSFLG_DIRTY_CPU_PROC
 						  | ERTS_PSFLG_DIRTY_IO_PROC));
 
     dirty_shadow_proc = erts_make_dirty_shadow_proc(esdp, c_p);
@@ -5434,11 +5351,11 @@ erts_call_dirty_bif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
     c_p_htop = c_p->htop;
 #endif
 
-    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+    erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
 
     result = (*bf)(dirty_shadow_proc, reg, I);
 
-    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+    erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
 
     ASSERT(c_p_htop == c_p->htop);
     ASSERT(dirty_shadow_proc->static_flags & ERTS_STC_FLG_SHADOW_PROC);
@@ -5461,7 +5378,7 @@ erts_call_dirty_bif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
 	}
 	else if (nep->func == ERTS_SCHED_BIF_TRAP_MARKER) {
 	    /* Dirty BIF did an ordinary trap... */
-	    ASSERT(!(erts_smp_atomic32_read_nob(&c_p->state)
+	    ASSERT(!(erts_atomic32_read_nob(&c_p->state)
 		     & (ERTS_PSFLG_DIRTY_CPU_PROC|ERTS_PSFLG_DIRTY_IO_PROC)));
 	    schedule(c_p, dirty_shadow_proc, NULL, NULL,
 		     dirty_bif_trap, (void *) dirty_shadow_proc->i,
@@ -5484,7 +5401,6 @@ erts_call_dirty_bif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
     return exiting;
 }
 
-#endif /* ERTS_DIRTY_SCHEDULERS */
 
 
 #ifdef HARDDEBUG
diff --git a/erts/emulator/beam/bif.h b/erts/emulator/beam/bif.h
index 01cca90a7a..a2bc883dbe 100644
--- a/erts/emulator/beam/bif.h
+++ b/erts/emulator/beam/bif.h
@@ -93,7 +93,7 @@ do {									\
 
 #define BUMP_REDS(p, gc) do {			   \
      ASSERT(p);		 			   \
-     ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(p));\
+     ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(p));\
      (p)->fcalls -= (gc); 			   \
      if ((p)->fcalls < 0) { 			   \
 	if (!ERTS_PROC_GET_SAVED_CALLS_BUF((p)))   \
@@ -498,10 +498,8 @@ erts_bif_prep_await_proc_exit_apply_trap(Process *c_p,
 					 Eterm args[],
 					 int nargs);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 int erts_call_dirty_bif(ErtsSchedulerData *esdp, Process *c_p,
 			BeamInstr *I, Eterm *reg);
-#endif
 
 BIF_RETTYPE
 erts_schedule_bif(Process *proc,
diff --git a/erts/emulator/beam/bif.tab b/erts/emulator/beam/bif.tab
index 10ca0b5066..33f6eef652 100644
--- a/erts/emulator/beam/bif.tab
+++ b/erts/emulator/beam/bif.tab
@@ -153,7 +153,11 @@ bif erlang:whereis/1
 bif erlang:spawn_opt/1
 bif erlang:setnode/2
 bif erlang:setnode/3
-bif erlang:dist_exit/3
+bif erlang:dist_get_stat/1
+bif erlang:dist_ctrl_input_handler/2
+bif erlang:dist_ctrl_put_data/2
+bif erlang:dist_ctrl_get_data/1
+bif erlang:dist_ctrl_get_data_notification/1
 
 # Static native functions in erts_internal
 bif erts_internal:port_info/1
@@ -181,6 +185,8 @@ bif erts_internal:system_check/1
 
 bif erts_internal:release_literal_area_switch/0
 
+bif erts_internal:scheduler_wall_time/1
+
 # inet_db support
 bif erlang:port_set_data/2
 bif erlang:port_get_data/1
@@ -623,7 +629,6 @@ bif re:inspect/2
 
 ubif erlang:is_map/1
 gcbif erlang:map_size/1
-bif maps:to_list/1
 bif maps:find/2
 bif maps:get/2
 bif maps:from_list/1
@@ -678,10 +683,16 @@ bif math:floor/1
 bif math:ceil/1
 bif math:fmod/2
 bif os:set_signal/2
-bif erts_internal:maps_to_list/2
 
 #
 # New in 20.1
 #
-
 bif erlang:iolist_to_iovec/1
+
+#
+# New in 21.0
+#
+
+bif erts_internal:new_connection/1
+bif erts_internal:abort_connection/2
+bif erts_internal:map_next/3
diff --git a/erts/emulator/beam/bif_instrs.tab b/erts/emulator/beam/bif_instrs.tab
new file mode 100644
index 0000000000..0932b8b985
--- /dev/null
+++ b/erts/emulator/beam/bif_instrs.tab
@@ -0,0 +1,539 @@
+// -*- c -*-
+//
+// %CopyrightBegin%
+//
+// Copyright Ericsson AB 2017. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// %CopyrightEnd%
+//
+
+// ================================================================
+// All guards with zero arguments have special instructions,
+// for example:
+//
+// 	self/0
+// 	node/0
+//
+// All other guard BIFs take one or two arguments.
+// ================================================================
+
+CALL_GUARD_BIF(BF, TmpReg, Dst) {
+    Eterm result;
+
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    c_p->fcalls = FCALLS;
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
+    ERTS_CHK_MBUF_SZ(c_p);
+    result = (*$BF)(c_p, $TmpReg, I);
+    ERTS_CHK_MBUF_SZ(c_p);
+    ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
+    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+    ERTS_HOLE_CHECK(c_p);
+    FCALLS = c_p->fcalls;
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    if (ERTS_LIKELY(is_value(result))) {
+        $Dst = result;
+        $NEXT0();
+    }
+}
+
+// Guard BIF in head.  On failure, ignore the error and jump
+// to the code for the next clause.  We don't support tracing
+// of guard BIFs.
+
+bif1(Fail, Bif, Src, Dst) {
+    ErtsBifFunc bf;
+    Eterm tmp_reg[1];
+
+    tmp_reg[0] = $Src;
+    bf = (BifFunction) $Bif;
+    $CALL_GUARD_BIF(bf, tmp_reg, $Dst);
+
+    $FAIL($Fail);
+}
+
+//
+// Guard BIF in body.  It can fail like any BIF.  No trace support.
+//
+
+bif1_body(Bif, Src, Dst) {
+    ErtsBifFunc bf;
+    Eterm tmp_reg[1];
+
+    tmp_reg[0] = $Src;
+    bf = (BifFunction) $Bif;
+    $CALL_GUARD_BIF(bf, tmp_reg, $Dst);
+
+    reg[0] = tmp_reg[0];
+    SWAPOUT;
+    I = handle_error(c_p, I, reg, ubif2mfa((void *) bf));
+    goto post_error_handling;
+}
+
+//
+// Guard bif in guard with two arguments ('and'/2, 'or'/2, 'xor'/2).
+//
+
+i_bif2(Fail, Bif, Src1, Src2, Dst) {
+    Eterm tmp_reg[2];
+    ErtsBifFunc bf;
+
+    tmp_reg[0] = $Src1;
+    tmp_reg[1] = $Src2;
+    bf = (ErtsBifFunc) $Bif;
+    $CALL_GUARD_BIF(bf, tmp_reg, $Dst);
+    $FAIL($Fail);
+}
+
+//
+// Guard bif in body with two arguments ('and'/2, 'or'/2, 'xor'/2).
+//
+
+i_bif2_body(Bif, Src1, Src2, Dst) {
+    Eterm tmp_reg[2];
+    ErtsBifFunc bf;
+
+    tmp_reg[0] = $Src1;
+    tmp_reg[1] = $Src2;
+    bf = (ErtsBifFunc) $Bif;
+    $CALL_GUARD_BIF(bf, tmp_reg, $Dst);
+    reg[0] = tmp_reg[0];
+    reg[1] = tmp_reg[1];
+    SWAPOUT;
+    I = handle_error(c_p, I, reg, ubif2mfa((void *) bf));
+    goto post_error_handling;
+}
+
+//
+// Garbage-collecting BIF with one argument in either guard or body.
+//
+
+i_gc_bif1(Fail, Bif, Src, Live, Dst) {
+    typedef Eterm (*GcBifFunction)(Process*, Eterm*, Uint);
+    GcBifFunction bf;
+    Eterm result;
+    Uint live = (Uint) $Live;
+
+    x(live) = $Src;
+    bf = (GcBifFunction) $Bif;
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    c_p->fcalls = FCALLS;
+    SWAPOUT;
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+    ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
+    ERTS_CHK_MBUF_SZ(c_p);
+    result = (*bf)(c_p, reg, live);
+    ERTS_CHK_MBUF_SZ(c_p);
+    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+    ERTS_REQ_PROC_MAIN_LOCK(c_p);
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+    SWAPIN;
+    ERTS_HOLE_CHECK(c_p);
+    FCALLS = c_p->fcalls;
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    if (ERTS_LIKELY(is_value(result))) {
+        $REFRESH_GEN_DEST();
+        $Dst = result;
+        $NEXT0();
+    }
+    if (ERTS_LIKELY($Fail != 0)) { /* Handle error in guard. */
+        $JUMP($Fail);
+    }
+
+    /* Handle error in body. */
+    x(0) = x(live);
+    I = handle_error(c_p, I, reg, gcbif2mfa((void *) bf));
+    goto post_error_handling;
+}
+
+//
+// Garbage-collecting BIF with two arguments in either guard or body.
+//
+
+i_gc_bif2(Fail, Bif, Live, Src1, Src2, Dst) {
+    typedef Eterm (*GcBifFunction)(Process*, Eterm*, Uint);
+    GcBifFunction bf;
+    Eterm result;
+    Uint live = (Uint) $Live;
+
+    /*
+     * XXX This calling convention does not make sense. 'live'
+     * should point out the first argument, not the second
+     * (i.e. 'live' should not be incremented below).
+     */
+    x(live) = $Src1;
+    x(live+1) = $Src2;
+    live++;
+
+    bf = (GcBifFunction) $Bif;
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    c_p->fcalls = FCALLS;
+    SWAPOUT;
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+    ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
+    ERTS_CHK_MBUF_SZ(c_p);
+    result = (*bf)(c_p, reg, live);
+    ERTS_CHK_MBUF_SZ(c_p);
+    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+    ERTS_REQ_PROC_MAIN_LOCK(c_p);
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+    SWAPIN;
+    ERTS_HOLE_CHECK(c_p);
+    FCALLS = c_p->fcalls;
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    if (ERTS_LIKELY(is_value(result))) {
+        $REFRESH_GEN_DEST();
+        $Dst = result;
+        $NEXT0();
+    }
+
+    if (ERTS_LIKELY($Fail != 0)) { /* Handle error in guard. */
+        $JUMP($Fail);
+    }
+
+    /* Handle error in body. */
+    live--;
+    x(0) = x(live);
+    x(1) = x(live+1);
+    I = handle_error(c_p, I, reg, gcbif2mfa((void *) bf));
+    goto post_error_handling;
+}
+
+//
+// Garbage-collecting BIF with three arguments in either guard or body.
+//
+
+i_gc_bif3(Fail, Bif, Live, Src2, Src3, Dst) {
+    typedef Eterm (*GcBifFunction)(Process*, Eterm*, Uint);
+    GcBifFunction bf;
+    Eterm result;
+    Uint live = (Uint) $Live;
+
+    /*
+     * XXX This calling convention does not make sense. 'live'
+     * should point out the first argument, not the third
+     * (i.e. 'live' should not be incremented below).
+     */
+    x(live) = x(SCRATCH_X_REG);
+    x(live+1) = $Src2;
+    x(live+2) = $Src3;
+    live += 2;
+
+    bf = (GcBifFunction) $Bif;
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    c_p->fcalls = FCALLS;
+    SWAPOUT;
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+    ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
+    ERTS_CHK_MBUF_SZ(c_p);
+    result = (*bf)(c_p, reg, live);
+    ERTS_CHK_MBUF_SZ(c_p);
+    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+    ERTS_REQ_PROC_MAIN_LOCK(c_p);
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+    SWAPIN;
+    ERTS_HOLE_CHECK(c_p);
+    FCALLS = c_p->fcalls;
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    if (ERTS_LIKELY(is_value(result))) {
+        $REFRESH_GEN_DEST();
+        $Dst = result;
+        $NEXT0();
+    }
+
+    /* Handle error in guard. */
+    if (ERTS_LIKELY($Fail != 0)) {
+        $JUMP($Fail);
+    }
+
+    /* Handle error in body. */
+    live -= 2;
+    x(0) = x(live);
+    x(1) = x(live+1);
+    x(2) = x(live+2);
+    I = handle_error(c_p, I, reg, gcbif2mfa((void *) bf));
+    goto post_error_handling;
+}
+
+//
+// The most general BIF call.  The BIF may build any amount of data
+// on the heap.  The result is always returned in r(0).
+//
+call_bif(Exp) {
+    ErtsBifFunc bf;
+    Eterm result;
+    ErlHeapFragment *live_hf_end;
+    Export *export = (Export*) $Exp;
+
+    if (!((FCALLS - 1) > 0 || (FCALLS-1) > neg_o_reds)) {
+        /* If we have run out of reductions, we do a context
+           switch before calling the bif */
+        c_p->arity = GET_BIF_ARITY(export);
+        c_p->current = &export->info.mfa;
+        goto context_switch3;
+    }
+
+    ERTS_MSACC_SET_BIF_STATE_CACHED_X(GET_BIF_MODULE(export),
+                                      GET_BIF_ADDRESS(export));
+
+    bf = GET_BIF_ADDRESS(export);
+
+    PRE_BIF_SWAPOUT(c_p);
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    c_p->fcalls = FCALLS - 1;
+    if (FCALLS <= 0) {
+        save_calls(c_p, export);
+    }
+    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
+    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+    live_hf_end = c_p->mbuf;
+    ERTS_CHK_MBUF_SZ(c_p);
+    result = (*bf)(c_p, reg, I);
+    ERTS_CHK_MBUF_SZ(c_p);
+    ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
+    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+    ERTS_HOLE_CHECK(c_p);
+    ERTS_REQ_PROC_MAIN_LOCK(c_p);
+    if (ERTS_IS_GC_DESIRED(c_p)) {
+        Uint arity = GET_BIF_ARITY(export);
+        result = erts_gc_after_bif_call_lhf(c_p, live_hf_end, result,
+                                            reg, arity);
+        E = c_p->stop;
+    }
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+    HTOP = HEAP_TOP(c_p);
+    FCALLS = c_p->fcalls;
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    /* We have to update the cache if we are enabled in order
+       to make sure no book keeping is done after we disabled
+       msacc. We don't always do this as it is quite expensive. */
+    if (ERTS_MSACC_IS_ENABLED_CACHED_X()) {
+        ERTS_MSACC_UPDATE_CACHE_X();
+    }
+    ERTS_MSACC_SET_STATE_CACHED_M_X(ERTS_MSACC_STATE_EMULATOR);
+    if (ERTS_LIKELY(is_value(result))) {
+        r(0) = result;
+        CHECK_TERM(r(0));
+        $NEXT0();
+    } else if (c_p->freason == TRAP) {
+        SET_CP(c_p, I+2);
+        SET_I(c_p->i);
+        SWAPIN;
+        Dispatch();
+    }
+
+    /*
+     * Error handling.  SWAPOUT is not needed because it was done above.
+     */
+    ASSERT(c_p->stop == E);
+    I = handle_error(c_p, I, reg, &export->info.mfa);
+    goto post_error_handling;
+}
+
+//
+// Send is almost a standard call-BIF with two arguments, except for:
+//   1. It cannot be traced.
+//   2. There is no pointer to the send_2 function stored in
+//      the instruction.
+//
+
+send() {
+    Eterm result;
+
+    if (!(FCALLS > 0 || FCALLS > neg_o_reds)) {
+        /* If we have run out of reductions, we do a context
+           switch before calling the bif */
+        c_p->arity = 2;
+        c_p->current = NULL;
+        goto context_switch3;
+    }
+
+    PRE_BIF_SWAPOUT(c_p);
+    c_p->fcalls = FCALLS - 1;
+    result = erl_send(c_p, r(0), x(1));
+    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+    ERTS_REQ_PROC_MAIN_LOCK(c_p);
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+    HTOP = HEAP_TOP(c_p);
+    FCALLS = c_p->fcalls;
+    if (ERTS_LIKELY(is_value(result))) {
+        r(0) = result;
+        CHECK_TERM(r(0));
+    } else if (c_p->freason == TRAP) {
+        SET_CP(c_p, I+1);
+        SET_I(c_p->i);
+        SWAPIN;
+        Dispatch();
+    } else {
+        goto find_func_info;
+    }
+}
+
+call_nif := nif_bif.call_nif.epilogue;
+apply_bif := nif_bif.apply_bif.epilogue;
+
+nif_bif.head() {
+    Eterm nif_bif_result;
+    Eterm bif_nif_arity;
+    BifFunction vbf;
+    ErlHeapFragment *live_hf_end;
+    ErtsCodeMFA *codemfa;
+}
+
+nif_bif.call_nif() {
+    /*
+     * call_nif is always first instruction in function:
+     *
+     * I[-3]: Module
+     * I[-2]: Function
+     * I[-1]: Arity
+     * I[0]: &&call_nif
+     * I[1]: Function pointer to NIF function
+     * I[2]: Pointer to erl_module_nif
+     * I[3]: Function pointer to dirty NIF
+     *
+     * This layout is determined by the NifExport struct
+     */
+
+    ERTS_MSACC_SET_STATE_CACHED_M_X(ERTS_MSACC_STATE_NIF);
+
+    codemfa = erts_code_to_codemfa(I);
+
+    c_p->current = codemfa; /* current and vbf set to please handle_error */
+
+    DTRACE_NIF_ENTRY(c_p, codemfa);
+
+    HEAVY_SWAPOUT;
+
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+    bif_nif_arity = codemfa->arity;
+    ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
+
+    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
+    {
+        typedef Eterm NifF(struct enif_environment_t*, int argc, Eterm argv[]);
+        NifF* fp = vbf = (NifF*) I[1];
+        struct enif_environment_t env;
+        ASSERT(c_p->scheduler_data);
+        live_hf_end = c_p->mbuf;
+        ERTS_CHK_MBUF_SZ(c_p);
+        erts_pre_nif(&env, c_p, (struct erl_module_nif*)I[2], NULL);
+        nif_bif_result = (*fp)(&env, bif_nif_arity, reg);
+        if (env.exception_thrown)
+            nif_bif_result = THE_NON_VALUE;
+        erts_post_nif(&env);
+        ERTS_CHK_MBUF_SZ(c_p);
+
+        PROCESS_MAIN_CHK_LOCKS(c_p);
+        ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+        ERTS_MSACC_SET_STATE_CACHED_M_X(ERTS_MSACC_STATE_EMULATOR);
+        ASSERT(!env.exiting);
+        ASSERT(!ERTS_PROC_IS_EXITING(c_p));
+    }
+
+    DTRACE_NIF_RETURN(c_p, codemfa);
+}
+
+nif_bif.apply_bif() {
+    /*
+     * At this point, I points to the code[0] in the export entry for
+     * the BIF:
+     *
+     * code[-3]: Module
+     * code[-2]: Function
+     * code[-1]: Arity
+     * code[0]: &&apply_bif
+     * code[1]: Function pointer to BIF function
+     */
+
+    if (!((FCALLS - 1) > 0 || (FCALLS - 1) > neg_o_reds)) {
+        /* If we have run out of reductions, we do a context
+           switch before calling the bif */
+        goto context_switch;
+    }
+
+    codemfa = erts_code_to_codemfa(I);
+
+    ERTS_MSACC_SET_BIF_STATE_CACHED_X(codemfa->module, (BifFunction)Arg(0));
+
+
+    /* In case we apply process_info/1,2 or load_nif/1 */
+    c_p->current = codemfa;
+    $SET_CP_I_ABS(I);     /* In case we apply check_process_code/2. */
+    c_p->arity = 0;       /* To allow garbage collection on ourselves
+                           * (check_process_code/2).
+                           */
+    DTRACE_BIF_ENTRY(c_p, codemfa);
+
+    SWAPOUT;
+    ERTS_DBG_CHK_REDS(c_p, FCALLS - 1);
+    c_p->fcalls = FCALLS - 1;
+    vbf = (BifFunction) Arg(0);
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+    bif_nif_arity = codemfa->arity;
+    ASSERT(bif_nif_arity <= 4);
+    ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
+    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+    {
+        ErtsBifFunc bf = vbf;
+        ASSERT(!ERTS_PROC_IS_EXITING(c_p));
+        live_hf_end = c_p->mbuf;
+        ERTS_CHK_MBUF_SZ(c_p);
+        nif_bif_result = (*bf)(c_p, reg, I);
+        ERTS_CHK_MBUF_SZ(c_p);
+        ASSERT(!ERTS_PROC_IS_EXITING(c_p) ||
+               is_non_value(nif_bif_result));
+        ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+        PROCESS_MAIN_CHK_LOCKS(c_p);
+    }
+    /* We have to update the cache if we are enabled in order
+       to make sure no book keeping is done after we disabled
+       msacc. We don't always do this as it is quite expensive. */
+    if (ERTS_MSACC_IS_ENABLED_CACHED_X())
+        ERTS_MSACC_UPDATE_CACHE_X();
+    ERTS_MSACC_SET_STATE_CACHED_M_X(ERTS_MSACC_STATE_EMULATOR);
+    DTRACE_BIF_RETURN(c_p, codemfa);
+}
+
+nif_bif.epilogue() {
+    ERTS_REQ_PROC_MAIN_LOCK(c_p);
+    ERTS_HOLE_CHECK(c_p);
+    if (ERTS_IS_GC_DESIRED(c_p)) {
+        nif_bif_result = erts_gc_after_bif_call_lhf(c_p, live_hf_end,
+                                                    nif_bif_result,
+                                                    reg, bif_nif_arity);
+    }
+    SWAPIN;  /* There might have been a garbage collection. */
+    FCALLS = c_p->fcalls;
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    if (ERTS_LIKELY(is_value(nif_bif_result))) {
+        r(0) = nif_bif_result;
+        CHECK_TERM(r(0));
+        SET_I(c_p->cp);
+        c_p->cp = 0;
+        Goto(*I);
+    } else if (c_p->freason == TRAP) {
+        SET_I(c_p->i);
+        if (c_p->flags & F_HIBERNATE_SCHED) {
+            c_p->flags &= ~F_HIBERNATE_SCHED;
+            goto do_schedule;
+        }
+        Dispatch();
+    }
+    I = handle_error(c_p, c_p->cp, reg, c_p->current);
+    goto post_error_handling;
+}
diff --git a/erts/emulator/beam/big.h b/erts/emulator/beam/big.h
index 48efce20e7..7556205063 100644
--- a/erts/emulator/beam/big.h
+++ b/erts/emulator/beam/big.h
@@ -70,7 +70,20 @@ typedef Uint  dsize_t;	 /* Vector size type */
 
 /* Check for small */
 #define IS_USMALL(sgn,x)  ((sgn) ? ((x) <= MAX_SMALL+1) : ((x) <= MAX_SMALL))
-#define IS_SSMALL(x)      (((x) >= MIN_SMALL) && ((x) <= MAX_SMALL))
+
+/*
+ * It seems that both clang and gcc will generate sub-optimal code
+ * for the more obvious way to write the range check:
+ *
+ *    #define IS_SSMALL(x)  (((x) >= MIN_SMALL) && ((x) <= MAX_SMALL))
+ *
+ * Note that IS_SSMALL() may be used in the 32-bit emulator with
+ * a Uint64 argument. Therefore, we must test the size of the argument
+ * to ensure that the cast does not discard the high-order 32 bits.
+ */
+#define _IS_SSMALL32(x) (((Uint32) ((((x)) >> (SMALL_BITS-1)) + 1)) < 2)
+#define _IS_SSMALL64(x) (((Uint64) ((((x)) >> (SMALL_BITS-1)) + 1)) < 2)
+#define IS_SSMALL(x) (sizeof(x) == sizeof(Uint32) ? _IS_SSMALL32(x) : _IS_SSMALL64(x))
 
 /* The heap size needed for a bignum */
 #define BIG_NEED_SIZE(x)  ((x) + 1)
diff --git a/erts/emulator/beam/break.c b/erts/emulator/beam/break.c
index e4c2801ea2..2cff05c7f3 100644
--- a/erts/emulator/beam/break.c
+++ b/erts/emulator/beam/break.c
@@ -111,8 +111,8 @@ process_killer(void)
 		    ErtsProcLocks rp_locks = ERTS_PROC_LOCKS_XSIG_SEND;
 		    erts_aint32_t state;
 		    erts_proc_inc_refc(rp);
-		    erts_smp_proc_lock(rp, rp_locks);
-		    state = erts_smp_atomic32_read_acqb(&rp->state);
+		    erts_proc_lock(rp, rp_locks);
+		    state = erts_atomic32_read_acqb(&rp->state);
 		    if (state & (ERTS_PSFLG_FREE
 				 | ERTS_PSFLG_EXITING
 				 | ERTS_PSFLG_ACTIVE
@@ -134,7 +134,7 @@ process_killer(void)
 						     NULL,
 						     0);
 		    }
-		    erts_smp_proc_unlock(rp, rp_locks);
+		    erts_proc_unlock(rp, rp_locks);
 		    erts_proc_dec_refc(rp);
 		}
 		case 'n': br = 1; break;
@@ -221,7 +221,7 @@ print_process_info(fmtfn_t to, void *to_arg, Process *p)
     /* Display the state */
     erts_print(to, to_arg, "State: ");
 
-    state = erts_smp_atomic32_read_acqb(&p->state);
+    state = erts_atomic32_read_acqb(&p->state);
     erts_dump_process_state(to, to_arg, state);
     if (state & ERTS_PSFLG_GC) {
         garbing = 1;
@@ -260,7 +260,7 @@ print_process_info(fmtfn_t to, void *to_arg, Process *p)
     erts_print(to, to_arg, "Spawned by: %T\n", p->parent);
     approx_started = (time_t) p->approx_started;
     erts_print(to, to_arg, "Started: %s", ctime(&approx_started));
-    ERTS_SMP_MSGQ_MV_INQ2PRIVQ(p);
+    ERTS_MSGQ_MV_INQ2PRIVQ(p);
     erts_print(to, to_arg, "Message queue length: %d\n", p->msg.len);
 
     /* display the message queue only if there is anything in it */
@@ -346,9 +346,7 @@ print_process_info(fmtfn_t to, void *to_arg, Process *p)
 	erts_program_counter_info(to, to_arg, p);
     } else {
 	erts_print(to, to_arg, "Stack dump:\n");
-#ifdef ERTS_SMP
 	if (!garbing)
-#endif
 	    erts_stack_dump(to, to_arg, p);
     }
 
@@ -360,11 +358,9 @@ print_process_info(fmtfn_t to, void *to_arg, Process *p)
 static void
 print_garb_info(fmtfn_t to, void *to_arg, Process* p)
 {
-#ifdef ERTS_SMP
-    /* ERTS_SMP: A scheduler is probably concurrently doing gc... */
+    /* A scheduler is probably concurrently doing gc... */
     if (!ERTS_IS_CRASH_DUMPING)
       return;
-#endif
     erts_print(to, to_arg, "New heap start: %bpX\n", p->heap);
     erts_print(to, to_arg, "New heap top: %bpX\n", p->htop);
     erts_print(to, to_arg, "Stack top: %bpX\n", p->stop);
@@ -512,7 +508,7 @@ do_break(void)
     erts_free_read_env(mode);
 #endif /* __WIN32__ */
 
-    ASSERT(erts_smp_thr_progress_is_blocking());
+    ASSERT(erts_thr_progress_is_blocking());
 
     erts_printf("\n"
 		"BREAK: (a)bort (c)ontinue (p)roc info (i)nfo (l)oaded\n"
@@ -708,9 +704,7 @@ crash_dump_limited_writer(void* vfdp, char* buf, size_t len)
 void
 erl_crash_dump_v(char *file, int line, char* fmt, va_list args)
 {
-#ifdef ERTS_SMP
     ErtsThrPrgrData tpd_buf; /* in case we aren't a managed thread... */
-#endif
     int fd;
     size_t envsz;
     time_t now;
@@ -730,7 +724,6 @@ erl_crash_dump_v(char *file, int line, char* fmt, va_list args)
     if (ERTS_SOMEONE_IS_CRASH_DUMPING)
 	return;
 
-#ifdef ERTS_SMP
     /* Order all managed threads to block, this has to be done
        first to guarantee that this is the only thread to generate
        crash dump. */
@@ -754,12 +747,9 @@ erl_crash_dump_v(char *file, int line, char* fmt, va_list args)
 #endif
 
     /* Allow us to pass certain places without locking... */
-    erts_smp_atomic32_set_mb(&erts_writing_erl_crash_dump, 1);
-    erts_smp_tsd_set(erts_is_crash_dumping_key, (void *) 1);
+    erts_atomic32_set_mb(&erts_writing_erl_crash_dump, 1);
+    erts_tsd_set(erts_is_crash_dumping_key, (void *) 1);
 
-#else /* !ERTS_SMP */
-    erts_writing_erl_crash_dump = 1;
-#endif /* ERTS_SMP */
 
     envsz = sizeof(env);
     /* ERL_CRASH_DUMP_SECONDS not set
@@ -875,7 +865,6 @@ erl_crash_dump_v(char *file, int line, char* fmt, va_list args)
     erts_print_nif_taints(to, to_arg);
     erts_cbprintf(to, to_arg, "Atoms: %d\n", atom_table_size());
 
-#ifdef USE_THREADS
     /* We want to note which thread it was that called erts_exit */
     if (erts_get_scheduler_data()) {
         erts_cbprintf(to, to_arg, "Calling Thread: scheduler:%d\n",
@@ -886,9 +875,6 @@ erl_crash_dump_v(char *file, int line, char* fmt, va_list args)
         else
             erts_cbprintf(to, to_arg, "Calling Thread: %p\n", erts_thr_self());
     }
-#else
-    erts_cbprintf(to, to_arg, "Calling Thread: scheduler:1\n");
-#endif
 
 #if defined(ERTS_HAVE_TRY_CATCH)
 
@@ -907,7 +893,6 @@ erl_crash_dump_v(char *file, int line, char* fmt, va_list args)
     }
 #endif
 
-#ifdef ERTS_SMP
 
 #ifdef ERTS_SYS_SUSPEND_SIGNAL
 
@@ -929,7 +914,6 @@ erl_crash_dump_v(char *file, int line, char* fmt, va_list args)
      */
     erts_thr_progress_fatal_error_wait(60000);
     /* Either worked or not... */
-#endif
 
 #ifndef ERTS_HAVE_TRY_CATCH
     /* This is safe to call here, as all schedulers are blocked */
diff --git a/erts/emulator/beam/bs_instrs.tab b/erts/emulator/beam/bs_instrs.tab
new file mode 100644
index 0000000000..9f03b19731
--- /dev/null
+++ b/erts/emulator/beam/bs_instrs.tab
@@ -0,0 +1,1021 @@
+// -*- c -*-
+//
+// %CopyrightBegin%
+//
+// Copyright Ericsson AB 2017. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// %CopyrightEnd%
+//
+
+%if ARCH_64
+BS_SAFE_MUL(A, B, Fail, Dst) {
+    Uint64 res = ($A) * ($B);
+    if (res / $B != $A) {
+        $Fail;
+    }
+    $Dst = res;
+}
+%else
+BS_SAFE_MUL(A, B, Fail, Dst) {
+    Uint64 res = (Uint64)($A) * (Uint64)($B);
+    if ((res >> (8*sizeof(Uint))) != 0) {
+        $Fail;
+    }
+    $Dst = res;
+}
+%endif
+
+BS_GET_FIELD_SIZE(Bits, Unit, Fail, Dst) {
+    Sint signed_size;
+    Uint uint_size;
+    Uint temp_bits;
+
+    if (is_small($Bits)) {
+        signed_size = signed_val($Bits);
+        if (signed_size < 0) {
+            $Fail;
+        }
+        uint_size = (Uint) signed_size;
+    } else {
+        if (!term_to_Uint($Bits, &temp_bits)) {
+            $Fail;
+        }
+        uint_size = temp_bits;
+    }
+    $BS_SAFE_MUL(uint_size, $Unit, $Fail, $Dst);
+}
+
+BS_GET_UNCHECKED_FIELD_SIZE(Bits, Unit, Fail, Dst) {
+    Sint signed_size;
+    Uint uint_size;
+    Uint temp_bits;
+
+    if (is_small($Bits)) {
+        signed_size = signed_val($Bits);
+        if (signed_size < 0) {
+            $Fail;
+        }
+        uint_size = (Uint) signed_size;
+    } else {
+        if (!term_to_Uint($Bits, &temp_bits)) {
+            $Fail;
+        }
+        uint_size = temp_bits;
+    }
+    $Dst = uint_size * $Unit;
+}
+
+TEST_BIN_VHEAP(VNh, Nh, Live) {
+    Uint need = $Nh;
+    if (E - HTOP < need || MSO(c_p).overhead + $VNh >= BIN_VHEAP_SZ(c_p)) {
+        SWAPOUT;
+        PROCESS_MAIN_CHK_LOCKS(c_p);
+        FCALLS -= erts_garbage_collect_nobump(c_p, need, reg, $Live, FCALLS);
+        ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+        PROCESS_MAIN_CHK_LOCKS(c_p);
+        SWAPIN;
+    }
+    HEAP_SPACE_VERIFIED(need);
+}
+
+i_bs_get_binary_all2(Fail, Ms, Live, Unit, Dst) {
+    ErlBinMatchBuffer *_mb;
+    Eterm _result;
+
+    $GC_TEST(0, ERL_SUB_BIN_SIZE, $Live);
+    _mb = ms_matchbuffer($Ms);
+    if (((_mb->size - _mb->offset) % $Unit) == 0) {
+        LIGHT_SWAPOUT;
+        _result = erts_bs_get_binary_all_2(c_p, _mb);
+        LIGHT_SWAPIN;
+        HEAP_SPACE_VERIFIED(0);
+        ASSERT(is_value(_result));
+        $Dst = _result;
+    } else {
+	HEAP_SPACE_VERIFIED(0);
+	$FAIL($Fail);
+    }
+}
+
+i_bs_get_binary2(Fail, Ms, Live, Sz, Flags, Dst) {
+    ErlBinMatchBuffer *_mb;
+    Eterm _result;
+    Uint _size;
+    $BS_GET_FIELD_SIZE($Sz, (($Flags) >> 3), $FAIL($Fail), _size);
+    $GC_TEST(0, ERL_SUB_BIN_SIZE, $Live);
+    _mb = ms_matchbuffer($Ms);
+    LIGHT_SWAPOUT;
+    _result = erts_bs_get_binary_2(c_p, _size, $Flags, _mb);
+    LIGHT_SWAPIN;
+    HEAP_SPACE_VERIFIED(0);
+    if (is_non_value(_result)) {
+        $FAIL($Fail);
+    } else {
+        $Dst = _result;
+    }
+}
+
+i_bs_get_binary_imm2(Fail, Ms, Live, Sz, Flags, Dst) {
+    ErlBinMatchBuffer *_mb;
+    Eterm _result;
+    $GC_TEST(0, heap_bin_size(ERL_ONHEAP_BIN_LIMIT), $Live);
+    _mb = ms_matchbuffer($Ms);
+    LIGHT_SWAPOUT;
+    _result = erts_bs_get_binary_2(c_p, $Sz, $Flags, _mb);
+    LIGHT_SWAPIN;
+    HEAP_SPACE_VERIFIED(0);
+    if (is_non_value(_result)) {
+        $FAIL($Fail);
+    } else {
+        $Dst = _result;
+    }
+}
+
+i_bs_get_float2(Fail, Ms, Live, Sz, Flags, Dst) {
+    ErlBinMatchBuffer *_mb;
+    Eterm _result;
+    Sint _size;
+
+    if (!is_small($Sz) || (_size = unsigned_val($Sz)) > 64) {
+        $FAIL($Fail);
+    }
+    _size *= (($Flags) >> 3);
+    $GC_TEST(0, FLOAT_SIZE_OBJECT, $Live);
+    _mb = ms_matchbuffer($Ms);
+    LIGHT_SWAPOUT;
+    _result = erts_bs_get_float_2(c_p, _size, ($Flags), _mb);
+    LIGHT_SWAPIN;
+    HEAP_SPACE_VERIFIED(0);
+    if (is_non_value(_result)) {
+        $FAIL($Fail);
+    } else {
+        $Dst = _result;
+    }
+}
+
+i_bs_skip_bits2(Fail, Ms, Bits, Unit) {
+    ErlBinMatchBuffer *_mb;
+    size_t new_offset;
+    Uint _size;
+
+    _mb = ms_matchbuffer($Ms);
+    $BS_GET_FIELD_SIZE($Bits, $Unit, $FAIL($Fail), _size);
+    new_offset = _mb->offset + _size;
+    if (new_offset <= _mb->size) {
+        _mb->offset = new_offset;
+    } else {
+        $FAIL($Fail);
+    }
+}
+
+i_bs_skip_bits_all2(Fail, Ms, Unit) {
+    ErlBinMatchBuffer *_mb;
+    _mb = ms_matchbuffer($Ms);
+    if (((_mb->size - _mb->offset) % $Unit) == 0) {
+        _mb->offset = _mb->size;
+    } else {
+        $FAIL($Fail);
+    }
+}
+
+i_bs_skip_bits_imm2(Fail, Ms, Bits) {
+    ErlBinMatchBuffer *_mb;
+    size_t new_offset;
+    _mb = ms_matchbuffer($Ms);
+    new_offset = _mb->offset + ($Bits);
+    if (new_offset <= _mb->size) {
+        _mb->offset = new_offset;
+    } else {
+        $FAIL($Fail);
+    }
+}
+
+i_new_bs_put_binary(Fail, Sz, Flags, Src) {
+    Sint _size;
+    $BS_GET_UNCHECKED_FIELD_SIZE($Sz, (($Flags) >> 3), $BADARG($Fail), _size);
+    if (!erts_new_bs_put_binary(ERL_BITS_ARGS_2(($Src), _size))) {
+        $BADARG($Fail);
+    }
+}
+
+i_new_bs_put_binary_all(Fail, Src, Unit) {
+    if (!erts_new_bs_put_binary_all(ERL_BITS_ARGS_2(($Src), ($Unit)))) {
+        $BADARG($Fail);
+    }
+}
+
+i_new_bs_put_binary_imm(Fail, Sz, Src) {
+    if (!erts_new_bs_put_binary(ERL_BITS_ARGS_2(($Src), ($Sz)))) {
+        $BADARG($Fail);
+    }
+}
+
+i_new_bs_put_float(Fail, Sz, Flags, Src) {
+    Sint _size;
+    $BS_GET_UNCHECKED_FIELD_SIZE($Sz, (($Flags) >> 3), $BADARG($Fail), _size);
+    if (!erts_new_bs_put_float(c_p, ($Src), _size, ($Flags))) {
+        $BADARG($Fail);
+    }
+}
+
+i_new_bs_put_float_imm(Fail, Sz, Flags, Src) {
+    if (!erts_new_bs_put_float(c_p, ($Src), ($Sz), ($Flags))) {
+        $BADARG($Fail);
+    }
+}
+
+i_new_bs_put_integer(Fail, Sz, Flags, Src) {
+   Sint _size;
+   $BS_GET_UNCHECKED_FIELD_SIZE($Sz, (($Flags) >> 3), $BADARG($Fail), _size);
+   if (!erts_new_bs_put_integer(ERL_BITS_ARGS_3(($Src), _size, ($Flags)))) {
+       $BADARG($Fail);
+   }
+}
+
+i_new_bs_put_integer_imm(Fail, Sz, Flags, Src) {
+    if (!erts_new_bs_put_integer(ERL_BITS_ARGS_3(($Src), ($Sz), ($Flags)))) {
+        $BADARG($Fail);
+    }
+}
+
+#
+# i_bs_init*
+#
+
+i_bs_init_fail_heap := bs_init.fail_heap.verify.execute;
+i_bs_init_fail := bs_init.fail.verify.execute;
+i_bs_init := bs_init.plain.execute;
+i_bs_init_heap := bs_init.heap.execute;
+
+bs_init.head() {
+    Eterm BsOp1;
+    Eterm BsOp2;
+}
+
+bs_init.fail_heap(Size, HeapAlloc) {
+    BsOp1 = $Size;
+    BsOp2 = $HeapAlloc;
+}
+
+bs_init.fail(Size) {
+    BsOp1 = $Size;
+    BsOp2 = 0;
+}
+
+bs_init.plain(Size) {
+    BsOp1 = $Size;
+    BsOp2 = 0;
+}
+
+bs_init.heap(Size, HeapAlloc) {
+    BsOp1 = $Size;
+    BsOp2 = $HeapAlloc;
+}
+
+bs_init.verify(Fail) {
+    if (is_small(BsOp1)) {
+        Sint size = signed_val(BsOp1);
+        if (size < 0) {
+            $BADARG($Fail);
+        }
+        BsOp1 = (Eterm) size;
+    } else {
+        Uint bytes;
+
+        if (!term_to_Uint(BsOp1, &bytes)) {
+            c_p->freason = bytes;
+            $FAIL_HEAD_OR_BODY($Fail);
+        }
+        if ((bytes >> (8*sizeof(Uint)-3)) != 0) {
+            $SYSTEM_LIMIT($Fail);
+        }
+        BsOp1 = (Eterm) bytes;
+    }
+}
+
+bs_init.execute(Live, Dst) {
+    if (BsOp1 <= ERL_ONHEAP_BIN_LIMIT) {
+        ErlHeapBin* hb;
+        Uint bin_need;
+
+        bin_need = heap_bin_size(BsOp1);
+        erts_bin_offset = 0;
+        erts_writable_bin = 0;
+        $GC_TEST(0, bin_need+BsOp2+ERL_SUB_BIN_SIZE, $Live);
+        hb = (ErlHeapBin *) HTOP;
+        HTOP += bin_need;
+        hb->thing_word = header_heap_bin(BsOp1);
+        hb->size = BsOp1;
+        erts_current_bin = (byte *) hb->data;
+        $Dst = make_binary(hb);
+    } else {
+        Binary* bptr;
+        ProcBin* pb;
+
+        erts_bin_offset = 0;
+        erts_writable_bin = 0;
+        $TEST_BIN_VHEAP(BsOp1 / sizeof(Eterm),
+                        BsOp2 + PROC_BIN_SIZE + ERL_SUB_BIN_SIZE, $Live);
+
+        /*
+         * Allocate the binary struct itself.
+         */
+        bptr = erts_bin_nrml_alloc(BsOp1);
+        erts_current_bin = (byte *) bptr->orig_bytes;
+
+        /*
+         * Now allocate the ProcBin on the heap.
+         */
+        pb = (ProcBin *) HTOP;
+        HTOP += PROC_BIN_SIZE;
+        pb->thing_word = HEADER_PROC_BIN;
+        pb->size = BsOp1;
+        pb->next = MSO(c_p).first;
+        MSO(c_p).first = (struct erl_off_heap_header*) pb;
+        pb->val = bptr;
+        pb->bytes = (byte*) bptr->orig_bytes;
+        pb->flags = 0;
+
+        OH_OVERHEAD(&(MSO(c_p)), BsOp1 / sizeof(Eterm));
+
+        $Dst = make_binary(pb);
+    }
+}
+
+#
+# i_bs_init_bits*
+#
+
+i_bs_init_bits           := bs_init_bits.plain.execute;
+i_bs_init_bits_heap      := bs_init_bits.heap.execute;
+i_bs_init_bits_fail      := bs_init_bits.fail.verify.execute;
+i_bs_init_bits_fail_heap := bs_init_bits.fail_heap.verify.execute;
+
+bs_init_bits.head() {
+    Eterm num_bits_term;
+    Uint num_bits;
+    Uint alloc;
+}
+
+bs_init_bits.plain(NumBits) {
+    num_bits = $NumBits;
+    alloc = 0;
+}
+
+bs_init_bits.heap(NumBits, Alloc) {
+    num_bits = $NumBits;
+    alloc = $Alloc;
+}
+
+bs_init_bits.fail(NumBitsTerm) {
+    num_bits_term = $NumBitsTerm;
+    alloc = 0;
+}
+
+bs_init_bits.fail_heap(NumBitsTerm, Alloc) {
+    num_bits_term = $NumBitsTerm;
+    alloc = $Alloc;
+}
+
+bs_init_bits.verify(Fail) {
+    if (is_small(num_bits_term)) {
+        Sint size = signed_val(num_bits_term);
+        if (size < 0) {
+            $BADARG($Fail);
+        }
+        num_bits = (Uint) size;
+    } else {
+        Uint bits;
+
+        if (!term_to_Uint(num_bits_term, &bits)) {
+            c_p->freason = bits;
+            $FAIL_HEAD_OR_BODY($Fail);
+        }
+        num_bits = (Uint) bits;
+    }
+}
+
+bs_init_bits.execute(Live, Dst) {
+     Eterm new_binary;
+     Uint num_bytes = ((Uint64)num_bits+(Uint64)7) >> 3;
+
+     if (num_bits & 7) {
+	 alloc += ERL_SUB_BIN_SIZE;
+     }
+     if (num_bytes <= ERL_ONHEAP_BIN_LIMIT) {
+	 alloc += heap_bin_size(num_bytes);
+     } else {
+	 alloc += PROC_BIN_SIZE;
+     }
+     $test_heap(alloc, $Live);
+
+     /* num_bits = Number of bits to build
+      * num_bytes = Number of bytes to allocate in the binary
+      * alloc = Total number of words to allocate on heap
+      * Operands: NotUsed NotUsed Dst
+      */
+     if (num_bytes <= ERL_ONHEAP_BIN_LIMIT) {
+	 ErlHeapBin* hb;
+
+	 erts_bin_offset = 0;
+	 erts_writable_bin = 0;
+	 hb = (ErlHeapBin *) HTOP;
+	 HTOP += heap_bin_size(num_bytes);
+	 hb->thing_word = header_heap_bin(num_bytes);
+	 hb->size = num_bytes;
+	 erts_current_bin = (byte *) hb->data;
+	 new_binary = make_binary(hb);
+
+     do_bits_sub_bin:
+	 if (num_bits & 7) {
+	     ErlSubBin* sb;
+
+	     sb = (ErlSubBin *) HTOP;
+	     HTOP += ERL_SUB_BIN_SIZE;
+	     sb->thing_word = HEADER_SUB_BIN;
+	     sb->size = num_bytes - 1;
+	     sb->bitsize = num_bits & 7;
+	     sb->offs = 0;
+	     sb->bitoffs = 0;
+	     sb->is_writable = 0;
+	     sb->orig = new_binary;
+	     new_binary = make_binary(sb);
+	 }
+	 HEAP_SPACE_VERIFIED(0);
+         $Dst = new_binary;
+     } else {
+	 Binary* bptr;
+	 ProcBin* pb;
+
+	 erts_bin_offset = 0;
+	 erts_writable_bin = 0;
+
+	 /*
+	  * Allocate the binary struct itself.
+	  */
+	 bptr = erts_bin_nrml_alloc(num_bytes);
+	 erts_current_bin = (byte *) bptr->orig_bytes;
+
+	 /*
+	  * Now allocate the ProcBin on the heap.
+	  */
+	 pb = (ProcBin *) HTOP;
+	 HTOP += PROC_BIN_SIZE;
+	 pb->thing_word = HEADER_PROC_BIN;
+	 pb->size = num_bytes;
+	 pb->next = MSO(c_p).first;
+	 MSO(c_p).first = (struct erl_off_heap_header*) pb;
+	 pb->val = bptr;
+	 pb->bytes = (byte*) bptr->orig_bytes;
+	 pb->flags = 0;
+	 OH_OVERHEAD(&(MSO(c_p)), pb->size / sizeof(Eterm));
+	 new_binary = make_binary(pb);
+	 goto do_bits_sub_bin;
+     }
+}
+
+bs_add(Fail, Src1, Src2, Unit, Dst) {
+    Eterm Op1 = $Src1;
+    Eterm Op2 = $Src2;
+    Uint unit = $Unit;
+
+    if (is_both_small(Op1, Op2)) {
+        Sint Arg1 = signed_val(Op1);
+        Sint Arg2 = signed_val(Op2);
+
+        if (Arg1 >= 0 && Arg2 >= 0) {
+            $BS_SAFE_MUL(Arg2, unit, $SYSTEM_LIMIT($Fail), Op1);
+            Op1 += Arg1;
+
+        store_bs_add_result:
+            if (Op1 <= MAX_SMALL) {
+                Op1 = make_small(Op1);
+            } else {
+                /*
+                 * May generate a heap fragment, but in this
+                 * particular case it is OK, since the value will be
+                 * stored into an x register (the GC will scan x
+                 * registers for references to heap fragments) and
+                 * there is no risk that value can be stored into a
+                 * location that is not scanned for heap-fragment
+                 * references (such as the heap).
+                 */
+                SWAPOUT;
+                Op1 = erts_make_integer(Op1, c_p);
+                HTOP = HEAP_TOP(c_p);
+            }
+            $Dst = Op1;
+            $NEXT0();
+        }
+        $BADARG($Fail);
+    } else {
+        Uint a;
+        Uint b;
+        Uint c;
+
+        /*
+         * Now we know that one of the arguments is
+         * not a small. We must convert both arguments
+         * to Uints and check for errors at the same time.
+         *
+         * Error checking is tricky.
+         *
+         * If one of the arguments is not numeric or
+         * not positive, the error reason is BADARG.
+         *
+         * Otherwise if both arguments are numeric,
+         * but at least one argument does not fit in
+         * an Uint, the reason is SYSTEM_LIMIT.
+         */
+
+        if (!term_to_Uint(Op1, &a)) {
+            if (a == BADARG) {
+                $BADARG($Fail);
+            }
+            if (!term_to_Uint(Op2, &b)) {
+                c_p->freason = b;
+                $FAIL_HEAD_OR_BODY($Fail);
+            }
+            $SYSTEM_LIMIT($Fail);
+        } else if (!term_to_Uint(Op2, &b)) {
+            c_p->freason = b;
+            $FAIL_HEAD_OR_BODY($Fail);
+        }
+
+        /*
+         * The arguments are now correct and stored in a and b.
+         */
+
+        $BS_SAFE_MUL(b, unit, $SYSTEM_LIMIT($Fail), c);
+        Op1 = a + c;
+        if (Op1 < a) {
+            /*
+             * If the result is less than one of the
+             * arguments, there must have been an overflow.
+             */
+            $SYSTEM_LIMIT($Fail);
+        }
+        goto store_bs_add_result;
+    }
+    /* No fallthrough */
+    ASSERT(0);
+}
+
+bs_put_string(Len, Ptr) {
+    erts_new_bs_put_string(ERL_BITS_ARGS_2((byte *) $Ptr, $Len));
+}
+
+i_bs_append(Fail, ExtraHeap, Live, Unit, Size, Dst) {
+    Uint live = $Live;
+    Uint res;
+
+    HEAVY_SWAPOUT;
+    reg[live] = x(SCRATCH_X_REG);
+    res = erts_bs_append(c_p, reg, live, $Size, $ExtraHeap, $Unit);
+    HEAVY_SWAPIN;
+    if (is_non_value(res)) {
+        /* c_p->freason is already set (to BADARG or SYSTEM_LIMIT). */
+        $FAIL_HEAD_OR_BODY($Fail);
+    }
+    $Dst = res;
+}
+
+i_bs_private_append(Fail, Unit, Size, Src, Dst) {
+    Eterm res;
+
+    res = erts_bs_private_append(c_p, $Src, $Size, $Unit);
+    if (is_non_value(res)) {
+        /* c_p->freason is already set (to BADARG or SYSTEM_LIMIT). */
+        $FAIL_HEAD_OR_BODY($Fail);
+    }
+    $Dst = res;
+}
+
+bs_init_writable() {
+    HEAVY_SWAPOUT;
+    r(0) = erts_bs_init_writable(c_p, r(0));
+    HEAVY_SWAPIN;
+}
+
+i_bs_utf8_size(Src, Dst) {
+    Eterm arg = $Src;
+    Eterm result;
+
+    /*
+     * Calculate the number of bytes needed to encode the source
+     * operand to UTF-8. If the source operand is invalid (e.g. wrong
+     * type or range) we return a nonsense integer result (0 or 4). We
+     * can get away with that because we KNOW that bs_put_utf8 will do
+     * full error checking.
+     */
+
+    if (arg < make_small(0x80UL)) {
+        result = make_small(1);
+    } else if (arg < make_small(0x800UL)) {
+        result = make_small(2);
+    } else if (arg < make_small(0x10000UL)) {
+        result = make_small(3);
+    } else {
+        result = make_small(4);
+    }
+    $Dst = result;
+}
+
+i_bs_put_utf8(Fail, Src) {
+    if (!erts_bs_put_utf8(ERL_BITS_ARGS_1($Src))) {
+        $BADARG($Fail);
+    }
+}
+
+i_bs_utf16_size(Src, Dst) {
+    Eterm arg = $Src;
+    Eterm result = make_small(2);
+
+    /*
+     * Calculate the number of bytes needed to encode the source
+     * operarand to UTF-16. If the source operand is invalid (e.g. wrong
+     * type or range) we return a nonsense integer result (2 or 4). We
+     * can get away with that because we KNOW that bs_put_utf16 will do
+     * full error checking.
+     */
+
+    if (arg >= make_small(0x10000UL)) {
+        result = make_small(4);
+    }
+    $Dst = result;
+}
+
+bs_put_utf16(Fail, Flags, Src) {
+    if (!erts_bs_put_utf16(ERL_BITS_ARGS_2($Src, $Flags))) {
+        $BADARG($Fail);
+    }
+}
+
+// Validate a value about to be stored in a binary.
+i_bs_validate_unicode(Fail, Src) {
+    Eterm val = $Src;
+
+    /*
+     * There is no need to untag the integer, but it IS necessary
+     * to make sure it is small (if the term is a bignum, it could
+     * slip through the test, and there is no further test that
+     * would catch it, since bit syntax construction silently masks
+     * too big numbers).
+     */
+    if (is_not_small(val) || val > make_small(0x10FFFFUL) ||
+        (make_small(0xD800UL) <= val && val <= make_small(0xDFFFUL))) {
+        $BADARG($Fail);
+    }
+}
+
+// Validate a value that has been matched out.
+i_bs_validate_unicode_retract(Fail, Src, Ms) {
+    /*
+     * There is no need to untag the integer, but it IS necessary
+     * to make sure it is small (a bignum pointer could fall in
+     * the valid range).
+     */
+
+    Eterm i = $Src;
+    if (is_not_small(i) || i > make_small(0x10FFFFUL) ||
+        (make_small(0xD800UL) <= i && i <= make_small(0xDFFFUL))) {
+        Eterm ms = $Ms;		/* Match context */
+        ErlBinMatchBuffer* mb;
+
+        /* Invalid value. Retract the position in the binary. */
+        mb = ms_matchbuffer(ms);
+        mb->offset -= 32;
+        $BADARG($Fail);
+    }
+}
+
+
+//
+// Matching of binaries.
+//
+
+i_bs_start_match2 := bs_start_match.fetch.execute;
+
+bs_start_match.head() {
+    Eterm context;
+}
+
+bs_start_match.fetch(Src) {
+    context = $Src;
+}
+
+bs_start_match.execute(Fail, Live, Slots, Dst) {
+    Uint slots;
+    Uint live;
+    Eterm header;
+    if (!is_boxed(context)) {
+        $FAIL($Fail);
+    }
+    header = *boxed_val(context);
+    slots = $Slots;
+    live = $Live;
+    if (header_is_bin_matchstate(header)) {
+        ErlBinMatchState* ms = (ErlBinMatchState *) boxed_val(context);
+        Uint actual_slots = HEADER_NUM_SLOTS(header);
+        ms->save_offset[0] = ms->mb.offset;
+        if (actual_slots < slots) {
+            ErlBinMatchState* dst;
+            Uint live = $Live;
+            Uint wordsneeded = ERL_BIN_MATCHSTATE_SIZE(slots);
+
+            $GC_TEST_PRESERVE(wordsneeded, live, context);
+            ms = (ErlBinMatchState *) boxed_val(context);
+            dst = (ErlBinMatchState *) HTOP;
+            *dst = *ms;
+            *HTOP = HEADER_BIN_MATCHSTATE(slots);
+            HTOP += wordsneeded;
+            HEAP_SPACE_VERIFIED(0);
+            $Dst = make_matchstate(dst);
+        }
+    } else if (is_binary_header(header)) {
+        Eterm result;
+        Uint wordsneeded = ERL_BIN_MATCHSTATE_SIZE(slots);
+        $GC_TEST_PRESERVE(wordsneeded, live, context);
+        HEAP_TOP(c_p) = HTOP;
+#ifdef DEBUG
+        c_p->stop = E;	/* Needed for checking in HeapOnlyAlloc(). */
+#endif
+        result = erts_bs_start_match_2(c_p, context, slots);
+        HTOP = HEAP_TOP(c_p);
+        HEAP_SPACE_VERIFIED(0);
+        if (is_non_value(result)) {
+            $FAIL($Fail);
+        }
+        $Dst = result;
+    } else {
+        $FAIL($Fail);
+    }
+}
+
+bs_test_zero_tail2(Fail, Ctx) {
+    ErlBinMatchBuffer *_mb;
+    _mb = (ErlBinMatchBuffer*) ms_matchbuffer($Ctx);
+    if (_mb->size != _mb->offset) {
+        $FAIL($Fail);
+    }
+}
+
+bs_test_tail_imm2(Fail, Ctx, Offset) {
+    ErlBinMatchBuffer *_mb;
+    _mb = ms_matchbuffer($Ctx);
+    if (_mb->size - _mb->offset != $Offset) {
+        $FAIL($Fail);
+    }
+}
+
+bs_test_unit(Fail, Ctx, Unit) {
+    ErlBinMatchBuffer *_mb;
+    _mb = ms_matchbuffer($Ctx);
+    if ((_mb->size - _mb->offset) % $Unit) {
+        $FAIL($Fail);
+    }
+}
+
+bs_test_unit8(Fail, Ctx) {
+    ErlBinMatchBuffer *_mb;
+    _mb = ms_matchbuffer($Ctx);
+    if ((_mb->size - _mb->offset) & 7) {
+        $FAIL($Fail);
+    }
+}
+
+i_bs_get_integer_8(Ctx, Fail, Dst) {
+    Eterm _result;
+    ErlBinMatchBuffer* _mb = ms_matchbuffer($Ctx);
+
+    if (_mb->size - _mb->offset < 8) {
+        $FAIL($Fail);
+    }
+    if (BIT_OFFSET(_mb->offset) != 0) {
+        _result = erts_bs_get_integer_2(c_p, 8, 0, _mb);
+    } else {
+        _result = make_small(_mb->base[BYTE_OFFSET(_mb->offset)]);
+        _mb->offset += 8;
+    }
+    $Dst = _result;
+}
+
+i_bs_get_integer_16(Ctx, Fail, Dst) {
+    Eterm _result;
+    ErlBinMatchBuffer* _mb = ms_matchbuffer($Ctx);
+
+    if (_mb->size - _mb->offset < 16) {
+        $FAIL($Fail);
+    }
+    if (BIT_OFFSET(_mb->offset) != 0) {
+        _result = erts_bs_get_integer_2(c_p, 16, 0, _mb);
+    } else {
+        _result = make_small(get_int16(_mb->base+BYTE_OFFSET(_mb->offset)));
+        _mb->offset += 16;
+    }
+    $Dst = _result;
+}
+
+%if ARCH_64
+i_bs_get_integer_32(Ctx, Fail, Dst) {
+    Uint32 _integer;
+    ErlBinMatchBuffer* _mb = ms_matchbuffer($Ctx);
+
+    if (_mb->size - _mb->offset < 32) {
+        $FAIL($Fail);
+    }
+    if (BIT_OFFSET(_mb->offset) != 0) {
+        _integer = erts_bs_get_unaligned_uint32(_mb);
+    } else {
+        _integer = get_int32(_mb->base + _mb->offset/8);
+    }
+    _mb->offset += 32;
+    $Dst = make_small(_integer);
+}
+%endif
+
+i_bs_get_integer_imm := bs_get_integer.fetch.execute;
+i_bs_get_integer_small_imm := bs_get_integer.fetch_small.execute;
+
+bs_get_integer.head() {
+    Eterm Ms, Sz;
+}
+
+bs_get_integer.fetch(Ctx, Size, Live) {
+    Uint wordsneeded;
+    Ms = $Ctx;
+    Sz = $Size;
+    wordsneeded = 1+WSIZE(NBYTES(Sz));
+    $GC_TEST_PRESERVE(wordsneeded, $Live, Ms);
+}
+
+bs_get_integer.fetch_small(Ctx, Size) {
+    Ms = $Ctx;
+    Sz = $Size;
+}
+
+bs_get_integer.execute(Fail, Flags, Dst) {
+    ErlBinMatchBuffer* mb;
+    Eterm result;
+
+    mb = ms_matchbuffer(Ms);
+    LIGHT_SWAPOUT;
+    result = erts_bs_get_integer_2(c_p, Sz, $Flags, mb);
+    LIGHT_SWAPIN;
+    HEAP_SPACE_VERIFIED(0);
+    if (is_non_value(result)) {
+        $FAIL($Fail);
+    }
+    $Dst = result;
+}
+
+i_bs_get_integer(Fail, Live, FlagsAndUnit, Ms, Sz, Dst) {
+    Uint flags;
+    Uint size;
+    Eterm ms;
+    ErlBinMatchBuffer* mb;
+    Eterm result;
+
+    flags = $FlagsAndUnit;
+    ms = $Ms;
+    $BS_GET_FIELD_SIZE($Sz, (flags >> 3), $FAIL($Fail), size);
+    if (size >= SMALL_BITS) {
+        Uint wordsneeded;
+        /* Check bits size before potential gc.
+         * We do not want a gc and then realize we don't need
+         * the allocated space (i.e. if the op fails).
+         *
+         * Remember to re-acquire the matchbuffer after gc.
+         */
+
+        mb = ms_matchbuffer(ms);
+        if (mb->size - mb->offset < size) {
+            $FAIL($Fail);
+        }
+        wordsneeded = 1+WSIZE(NBYTES((Uint) size));
+        $GC_TEST_PRESERVE(wordsneeded, $Live, ms);
+    }
+    mb = ms_matchbuffer(ms);
+    LIGHT_SWAPOUT;
+    result = erts_bs_get_integer_2(c_p, size, flags, mb);
+    LIGHT_SWAPIN;
+    HEAP_SPACE_VERIFIED(0);
+    if (is_non_value(result)) {
+        $FAIL($Fail);
+    }
+    $Dst = result;
+}
+
+i_bs_get_utf8(Ctx, Fail, Dst) {
+    ErlBinMatchBuffer* mb = ms_matchbuffer($Ctx);
+    Eterm result = erts_bs_get_utf8(mb);
+
+    if (is_non_value(result)) {
+        $FAIL($Fail);
+    }
+    $Dst = result;
+}
+
+i_bs_get_utf16(Ctx, Fail, Flags, Dst) {
+    ErlBinMatchBuffer* mb = ms_matchbuffer($Ctx);
+    Eterm result = erts_bs_get_utf16(mb, $Flags);
+
+    if (is_non_value(result)) {
+        $FAIL($Fail);
+    }
+    $Dst = result;
+}
+
+bs_context_to_binary := ctx_to_bin.fetch.execute;
+i_bs_get_binary_all_reuse := ctx_to_bin.fetch_bin.execute;
+
+ctx_to_bin.head() {
+    Eterm context;
+    ErlBinMatchBuffer* mb;
+    Uint size;
+    Uint offs;
+}
+
+ctx_to_bin.fetch(Src) {
+    context = $Src;
+    if (is_boxed(context) &&
+        header_is_bin_matchstate(*boxed_val(context))) {
+        ErlBinMatchState* ms;
+        ms = (ErlBinMatchState *) boxed_val(context);
+        mb = &ms->mb;
+        offs = ms->save_offset[0];
+        size = mb->size - offs;
+    } else {
+        $NEXT0();
+    }
+}
+
+ctx_to_bin.fetch_bin(Src, Fail, Unit) {
+    context = $Src;
+    mb = ms_matchbuffer(context);
+    size = mb->size - mb->offset;
+    if (size % $Unit != 0) {
+        $FAIL($Fail);
+    }
+    offs = mb->offset;
+}
+
+ctx_to_bin.execute() {
+    Uint hole_size;
+    Uint orig = mb->orig;
+    ErlSubBin* sb = (ErlSubBin *) boxed_val(context);
+    hole_size = 1 + header_arity(sb->thing_word) - ERL_SUB_BIN_SIZE;
+    sb->thing_word = HEADER_SUB_BIN;
+    sb->size = BYTE_OFFSET(size);
+    sb->bitsize = BIT_OFFSET(size);
+    sb->offs = BYTE_OFFSET(offs);
+    sb->bitoffs = BIT_OFFSET(offs);
+    sb->is_writable = 0;
+    sb->orig = orig;
+    if (hole_size) {
+        sb[1].thing_word = make_pos_bignum_header(hole_size-1);
+    }
+}
+
+i_bs_match_string(Ctx, Fail, Bits, Ptr) {
+    byte* bytes = (byte *) $Ptr;
+    Uint bits = $Bits;
+    ErlBinMatchBuffer* mb;
+    Uint offs;
+
+    mb = ms_matchbuffer($Ctx);
+    if (mb->size - mb->offset < bits) {
+        $FAIL($Fail);
+    }
+    offs = mb->offset & 7;
+    if (offs == 0 && (bits & 7) == 0) {
+        if (sys_memcmp(bytes, mb->base+(mb->offset>>3), bits>>3)) {
+            $FAIL($Fail);
+        }
+    } else if (erts_cmp_bits(bytes, 0, mb->base+(mb->offset>>3), mb->offset & 7, bits)) {
+        $FAIL($Fail);
+    }
+    mb->offset += bits;
+}
+
+i_bs_save2(Src, Slot) {
+    ErlBinMatchState* _ms = (ErlBinMatchState*) boxed_val((Eterm) $Src);
+    _ms->save_offset[$Slot] = _ms->mb.offset;
+}
+
+i_bs_restore2(Src, Slot) {
+    ErlBinMatchState* _ms = (ErlBinMatchState*) boxed_val((Eterm) $Src);
+    _ms->mb.offset = _ms->save_offset[$Slot];
+}
diff --git a/erts/emulator/beam/code_ix.c b/erts/emulator/beam/code_ix.c
index 8a3d1b20b4..34e46f5f33 100644
--- a/erts/emulator/beam/code_ix.c
+++ b/erts/emulator/beam/code_ix.c
@@ -34,8 +34,8 @@
 # define CIX_TRACE(text)
 #endif
 
-erts_smp_atomic32_t the_active_code_index;
-erts_smp_atomic32_t the_staging_code_index;
+erts_atomic32_t the_active_code_index;
+erts_atomic32_t the_staging_code_index;
 
 static Process* code_writing_process = NULL;
 struct code_write_queue_item {
@@ -43,7 +43,7 @@ struct code_write_queue_item {
     struct code_write_queue_item* next;
 };
 static struct code_write_queue_item* code_write_queue = NULL;
-static erts_smp_mtx_t code_write_permission_mtx;
+static erts_mtx_t code_write_permission_mtx;
 
 #ifdef ERTS_ENABLE_LOCK_CHECK
 static erts_tsd_key_t has_code_write_permission;
@@ -55,9 +55,9 @@ void erts_code_ix_init(void)
      * single threaded with active and staging set both to zero.
      * Preloading is finished by a commit that will set things straight.
      */
-    erts_smp_atomic32_init_nob(&the_active_code_index, 0);
-    erts_smp_atomic32_init_nob(&the_staging_code_index, 0);
-    erts_smp_mtx_init(&code_write_permission_mtx, "code_write_permission", NIL,
+    erts_atomic32_init_nob(&the_active_code_index, 0);
+    erts_atomic32_init_nob(&the_staging_code_index, 0);
+    erts_mtx_init(&code_write_permission_mtx, "code_write_permission", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
 #ifdef ERTS_ENABLE_LOCK_CHECK
     erts_tsd_key_create(&has_code_write_permission,
@@ -91,9 +91,9 @@ void erts_commit_staging_code_ix(void)
     /* We need to this lock as we are now making the staging export table active */
     export_staging_lock();
     ix = erts_staging_code_ix();
-    erts_smp_atomic32_set_nob(&the_active_code_index, ix);
+    erts_atomic32_set_nob(&the_active_code_index, ix);
     ix = (ix + 1) % ERTS_NUM_CODE_IX;
-    erts_smp_atomic32_set_nob(&the_staging_code_index, ix);
+    erts_atomic32_set_nob(&the_staging_code_index, ix);
     export_staging_unlock();
     erts_tracer_nif_clear();
     CIX_TRACE("activate");
@@ -115,12 +115,10 @@ void erts_abort_staging_code_ix(void)
 int erts_try_seize_code_write_permission(Process* c_p)
 {
     int success;
-#ifdef ERTS_SMP
-    ASSERT(!erts_smp_thr_progress_is_blocking()); /* to avoid deadlock */
-#endif
+    ASSERT(!erts_thr_progress_is_blocking()); /* to avoid deadlock */
     ASSERT(c_p != NULL);
 
-    erts_smp_mtx_lock(&code_write_permission_mtx);
+    erts_mtx_lock(&code_write_permission_mtx);
     success = (code_writing_process == NULL);
     if (success) {
 	code_writing_process = c_p;
@@ -138,21 +136,21 @@ int erts_try_seize_code_write_permission(Process* c_p)
 	code_write_queue = qitem;
 	erts_suspend(c_p, ERTS_PROC_LOCK_MAIN, NULL);
     }
-   erts_smp_mtx_unlock(&code_write_permission_mtx);
+   erts_mtx_unlock(&code_write_permission_mtx);
    return success;
 }
 
 void erts_release_code_write_permission(void)
 {
-    erts_smp_mtx_lock(&code_write_permission_mtx);
-    ERTS_SMP_LC_ASSERT(erts_has_code_write_permission());
+    erts_mtx_lock(&code_write_permission_mtx);
+    ERTS_LC_ASSERT(erts_has_code_write_permission());
     while (code_write_queue != NULL) { /* unleash the entire herd */
 	struct code_write_queue_item* qitem = code_write_queue;
-	erts_smp_proc_lock(qitem->p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_lock(qitem->p, ERTS_PROC_LOCK_STATUS);
 	if (!ERTS_PROC_IS_EXITING(qitem->p)) {
 	    erts_resume(qitem->p, ERTS_PROC_LOCK_STATUS);
 	}
-	erts_smp_proc_unlock(qitem->p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(qitem->p, ERTS_PROC_LOCK_STATUS);
 	code_write_queue = qitem->next;
 	erts_proc_dec_refc(qitem->p);
 	erts_free(ERTS_ALC_T_CODE_IX_LOCK_Q, qitem);
@@ -161,7 +159,7 @@ void erts_release_code_write_permission(void)
 #ifdef ERTS_ENABLE_LOCK_CHECK
     erts_tsd_set(has_code_write_permission, (void *) 0);
 #endif
-    erts_smp_mtx_unlock(&code_write_permission_mtx);
+    erts_mtx_unlock(&code_write_permission_mtx);
 }
 
 #ifdef ERTS_ENABLE_LOCK_CHECK
diff --git a/erts/emulator/beam/code_ix.h b/erts/emulator/beam/code_ix.h
index a28b0cd36e..42976d2301 100644
--- a/erts/emulator/beam/code_ix.h
+++ b/erts/emulator/beam/code_ix.h
@@ -176,7 +176,7 @@ int erts_has_code_write_permission(void);
 ERTS_GLB_INLINE
 BeamInstr *erts_codeinfo_to_code(ErtsCodeInfo *ci)
 {
-    ASSERT(ci->op == (BeamInstr) BeamOp(op_i_func_info_IaaI) || !ci->op);
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI) || !ci->op);
     ASSERT_MFA(&ci->mfa);
     return (BeamInstr*)(ci + 1);
 }
@@ -185,7 +185,7 @@ ERTS_GLB_INLINE
 ErtsCodeInfo *erts_code_to_codeinfo(BeamInstr *I)
 {
     ErtsCodeInfo *ci = ((ErtsCodeInfo *)(((char *)(I)) - sizeof(ErtsCodeInfo)));
-    ASSERT(ci->op == (BeamInstr) BeamOp(op_i_func_info_IaaI) || !ci->op);
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI) || !ci->op);
     ASSERT_MFA(&ci->mfa);
     return ci;
 }
@@ -205,16 +205,16 @@ ErtsCodeMFA *erts_code_to_codemfa(BeamInstr *I)
     return mfa;
 }
 
-extern erts_smp_atomic32_t the_active_code_index;
-extern erts_smp_atomic32_t the_staging_code_index;
+extern erts_atomic32_t the_active_code_index;
+extern erts_atomic32_t the_staging_code_index;
 
 ERTS_GLB_INLINE ErtsCodeIndex erts_active_code_ix(void)
 {
-    return erts_smp_atomic32_read_nob(&the_active_code_index);
+    return erts_atomic32_read_nob(&the_active_code_index);
 }
 ERTS_GLB_INLINE ErtsCodeIndex erts_staging_code_ix(void)
 {
-    return erts_smp_atomic32_read_nob(&the_staging_code_index);
+    return erts_atomic32_read_nob(&the_staging_code_index);
 }
 
 #endif /* ERTS_GLB_INLINE_INCL_FUNC_DEF */
diff --git a/erts/emulator/beam/copy.c b/erts/emulator/beam/copy.c
index fefde256d7..10bf197405 100644
--- a/erts/emulator/beam/copy.c
+++ b/erts/emulator/beam/copy.c
@@ -845,7 +845,7 @@ Eterm copy_struct_x(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap, Uint
 		    funp = (ErlFunThing *) tp;
 		    funp->next = off_heap->first;
 		    off_heap->first = (struct erl_off_heap_header*) funp;
-		    erts_smp_refc_inc(&funp->fe->refc, 2);
+		    erts_refc_inc(&funp->fe->refc, 2);
 		    *argp = make_fun(tp);
 		}
 		break;
@@ -854,7 +854,7 @@ Eterm copy_struct_x(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap, Uint
 	    case EXTERNAL_REF_SUBTAG:
 		{
 		  ExternalThing *etp = (ExternalThing *) objp;
-		  erts_smp_refc_inc(&etp->node->refc, 2);
+		  erts_refc_inc(&etp->node->refc, 2);
 		}
 	    L_off_heap_node_container_common:
 		{
@@ -1531,7 +1531,7 @@ Uint copy_shared_perform(Eterm obj, Uint size, erts_shcopy_t *info,
 		}
 		funp->next = off_heap->first;
 		off_heap->first = (struct erl_off_heap_header*) funp;
-		erts_smp_refc_inc(&funp->fe->refc, 2);
+		erts_refc_inc(&funp->fe->refc, 2);
 		goto cleanup_next;
 	    }
 	    case MAP_SUBTAG:
@@ -1658,7 +1658,7 @@ Uint copy_shared_perform(Eterm obj, Uint size, erts_shcopy_t *info,
 	    case EXTERNAL_REF_SUBTAG:
 	    {
 		ExternalThing *etp = (ExternalThing *) ptr;
-		erts_smp_refc_inc(&etp->node->refc, 2);
+		erts_refc_inc(&etp->node->refc, 2);
 	    }
 	  off_heap_node_container_common:
 	    {
@@ -1855,7 +1855,7 @@ Eterm copy_shallow(Eterm* ptr, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 	    case FUN_SUBTAG:
 		{
 		    ErlFunThing* funp = (ErlFunThing *) (tp-1);
-		    erts_smp_refc_inc(&funp->fe->refc, 2);
+		    erts_refc_inc(&funp->fe->refc, 2);
 		}
 		goto off_heap_common;
 	    case EXTERNAL_PID_SUBTAG:
@@ -1863,7 +1863,7 @@ Eterm copy_shallow(Eterm* ptr, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 	    case EXTERNAL_REF_SUBTAG:
 		{
 		    ExternalThing* etp = (ExternalThing *) (tp-1);
-		    erts_smp_refc_inc(&etp->node->refc, 2);
+		    erts_refc_inc(&etp->node->refc, 2);
 		}
 	    off_heap_common:
 		{
diff --git a/erts/emulator/beam/dist.c b/erts/emulator/beam/dist.c
index 9fddac8980..7ff7462bf6 100644
--- a/erts/emulator/beam/dist.c
+++ b/erts/emulator/beam/dist.c
@@ -103,25 +103,16 @@ dist_msg_dbg(ErtsDistExternal *edep, char *what, byte *buf, int sz)
 
 
 
-#define PASS_THROUGH 'p'        /* This code should go */
-
 int erts_is_alive; /* System must be blocked on change */
 int erts_dist_buf_busy_limit;
 
 
 /* distribution trap functions */
-Export* dsend2_trap = NULL;
-Export* dsend3_trap = NULL;
-/*Export* dsend_nosuspend_trap = NULL;*/
-Export* dlink_trap = NULL;
-Export* dunlink_trap = NULL;
 Export* dmonitor_node_trap = NULL;
-Export* dgroup_leader_trap = NULL;
-Export* dexit_trap = NULL;
 Export* dmonitor_p_trap = NULL;
 
 /* local variables */
-
+static Export *dist_ctrl_put_data_trap;
 
 /* forward declarations */
 
@@ -129,9 +120,10 @@ static void clear_dist_entry(DistEntry*);
 static int dsig_send_ctl(ErtsDSigData* dsdp, Eterm ctl, int force_busy);
 static void send_nodes_mon_msgs(Process *, Eterm, Eterm, Eterm, Eterm);
 static void init_nodes_monitors(void);
+static Sint abort_connection(DistEntry* dep, Uint32 conn_id);
 
-static erts_smp_atomic_t no_caches;
-static erts_smp_atomic_t no_nodes;
+static erts_atomic_t no_caches;
+static erts_atomic_t no_nodes;
 
 struct {
     Eterm reason;
@@ -144,8 +136,8 @@ delete_cache(ErtsAtomCache *cache)
 {
     if (cache) {
 	erts_free(ERTS_ALC_T_DCACHE, (void *) cache);
-	ASSERT(erts_smp_atomic_read_nob(&no_caches) > 0);
-	erts_smp_atomic_dec_nob(&no_caches);
+	ASSERT(erts_atomic_read_nob(&no_caches) > 0);
+	erts_atomic_dec_nob(&no_caches);
     }
 }
 
@@ -156,14 +148,12 @@ create_cache(DistEntry *dep)
     int i;
     ErtsAtomCache *cp;
 
-    ERTS_SMP_LC_ASSERT(
-	is_internal_port(dep->cid)
-	&& erts_lc_is_port_locked(erts_port_lookup_raw(dep->cid)));
+    ERTS_LC_ASSERT(is_nil(dep->cid));
     ASSERT(!dep->cache);
 
     dep->cache = cp = (ErtsAtomCache*) erts_alloc(ERTS_ALC_T_DCACHE,
 						  sizeof(ErtsAtomCache));
-    erts_smp_atomic_inc_nob(&no_caches);
+    erts_atomic_inc_nob(&no_caches);
     for (i = 0; i < sizeof(cp->in_arr)/sizeof(cp->in_arr[0]); i++) {
 	cp->in_arr[i] = THE_NON_VALUE;
 	cp->out_arr[i] = THE_NON_VALUE;
@@ -172,15 +162,17 @@ create_cache(DistEntry *dep)
 
 Uint erts_dist_cache_size(void)
 {
-    return (Uint) erts_smp_atomic_read_mb(&no_caches)*sizeof(ErtsAtomCache);
+    return (Uint) erts_atomic_read_mb(&no_caches)*sizeof(ErtsAtomCache);
 }
 
 static ErtsProcList *
-get_suspended_on_de(DistEntry *dep, Uint32 unset_qflgs)
+get_suspended_on_de(DistEntry *dep, erts_aint32_t unset_qflgs)
 {
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_mtx_is_locked(&dep->qlock));
-    dep->qflgs &= ~unset_qflgs;
-    if (dep->qflgs & ERTS_DE_QFLG_EXIT) {
+    erts_aint32_t qflgs;
+    ERTS_LC_ASSERT(erts_lc_mtx_is_locked(&dep->qlock));
+    qflgs = erts_atomic32_read_band_acqb(&dep->qflgs, ~unset_qflgs);
+    qflgs &= ~unset_qflgs;
+    if (qflgs & ERTS_DE_QFLG_EXIT) {
 	/* No resume when exit has been scheduled */
 	return NULL;
     }
@@ -283,17 +275,15 @@ static void doit_monitor_net_exits(ErtsMonitor *mon, void *vnecp)
 	    watched = (is_atom(rmon->name)
 		       ? TUPLE2(lhp, rmon->name, dep->sysname)
 		       : rmon->u.pid);
-#ifdef ERTS_SMP
 	    rp_locks |= ERTS_PROC_LOCKS_MSG_SEND;
-	    erts_smp_proc_lock(rp, ERTS_PROC_LOCKS_MSG_SEND);
-#endif
+	    erts_proc_lock(rp, ERTS_PROC_LOCKS_MSG_SEND);
 	    erts_queue_monitor_message(rp, &rp_locks, mon->ref, am_process, 
 				       watched, am_noconnection);
 	    erts_destroy_monitor(rmon);
 	}
 	UnUseTmpHeapNoproc(3);
     }
-    erts_smp_proc_unlock(rp, rp_locks);
+    erts_proc_unlock(rp, rp_locks);
  done:
     erts_destroy_monitor(mon);
 }
@@ -342,7 +332,7 @@ static void doit_link_net_exits_sub(ErtsLink *sublnk, void *vlnecp)
 		trace_proc(NULL, 0, rp, am_getting_unlinked, sublnk->pid);
 	    }
 	}
-	erts_smp_proc_unlock(rp, rp_locks);
+	erts_proc_unlock(rp, rp_locks);
     }
  done:
     erts_destroy_link(sublnk);
@@ -384,7 +374,7 @@ static void doit_node_link_net_exits(ErtsLink *lnk, void *vnecp)
 	rp = erts_proc_lookup(lnk->pid);
 	if (!rp)
 	    goto done;
-	erts_smp_proc_lock(rp, rp_locks);
+	erts_proc_lock(rp, rp_locks);
         if (!ERTS_PROC_IS_EXITING(rp)) {
             rlnk = erts_remove_link(&ERTS_P_LINKS(rp), name);
             if (rlnk != NULL) {
@@ -403,7 +393,7 @@ static void doit_node_link_net_exits(ErtsLink *lnk, void *vnecp)
                 erts_queue_message(rp, rp_locks, msgp, tup, am_system);
             }
         }
-	erts_smp_proc_unlock(rp, rp_locks);
+	erts_proc_unlock(rp, rp_locks);
     }
  done:
     erts_destroy_link(lnk);
@@ -415,16 +405,16 @@ set_node_not_alive(void *unused)
     ErlHeapFragment *bp;
     Eterm nodename = erts_this_dist_entry->sysname;
 
-    ASSERT(erts_smp_atomic_read_nob(&no_nodes) == 0);
+    ASSERT(erts_atomic_read_nob(&no_nodes) == 0);
 
-    erts_smp_thr_progress_block();
+    erts_thr_progress_block();
     erts_set_this_node(am_Noname, 0);
     erts_is_alive = 0;
     send_nodes_mon_msgs(NULL, am_nodedown, nodename, am_visible, nodedown.reason);
     nodedown.reason = NIL;
     bp = nodedown.bp;
     nodedown.bp = NULL;
-    erts_smp_thr_progress_unblock();
+    erts_thr_progress_unblock();
     if (bp)
 	free_message_buffer(bp);
 }
@@ -432,7 +422,7 @@ set_node_not_alive(void *unused)
 static ERTS_INLINE void
 dec_no_nodes(void)
 {
-    erts_aint_t no = erts_smp_atomic_dec_read_mb(&no_nodes);
+    erts_aint_t no = erts_atomic_dec_read_mb(&no_nodes);
     ASSERT(no >= 0);
     ASSERT(erts_get_scheduler_id()); /* Need to be a scheduler */
     if (no == 0)
@@ -445,12 +435,40 @@ static ERTS_INLINE void
 inc_no_nodes(void)
 {
 #ifdef DEBUG
-    erts_aint_t no = erts_smp_atomic_read_nob(&no_nodes);
+    erts_aint_t no = erts_atomic_read_nob(&no_nodes);
     ASSERT(erts_is_alive ? no > 0 : no == 0);
 #endif
-    erts_smp_atomic_inc_mb(&no_nodes);
+    erts_atomic_inc_mb(&no_nodes);
 }
-	
+
+static void
+kill_dist_ctrl_proc(void *vpid)
+{
+    Eterm pid = (Eterm) vpid;
+    ErtsProcLocks rp_locks = ERTS_PROC_LOCKS_XSIG_SEND;
+    Process *rp = erts_pid2proc(NULL, 0, pid, rp_locks);
+    if (rp) {
+        erts_send_exit_signal(NULL, rp->common.id, rp, &rp_locks,
+                              am_kill, NIL, NULL, 0);
+        if (rp_locks)
+            erts_proc_unlock(rp, rp_locks);
+    }
+}
+
+static void
+schedule_kill_dist_ctrl_proc(Eterm pid)
+{
+    ErtsSchedulerData *esdp = erts_get_scheduler_data();
+    int sched_id = 1;
+    if (!esdp || ERTS_SCHEDULER_IS_DIRTY(esdp))
+        sched_id = 1;
+    else
+        sched_id = (int) esdp->no;
+    erts_schedule_misc_aux_work(sched_id,
+                                kill_dist_ctrl_proc,
+                                (void *) (UWord) pid);
+}
+
 /*
  * proc is currently running or exiting process.
  */
@@ -460,58 +478,83 @@ int erts_do_net_exits(DistEntry *dep, Eterm reason)
 
     if (dep == erts_this_dist_entry) {  /* Net kernel has died (clean up!!) */
 	DistEntry *tdep;
-	int no_dist_port = 0;
+	int no_dist_ctrl;
+        int no_pending;
 	Eterm nd_reason = (reason == am_no_network
 			   ? am_no_network
 			   : am_net_kernel_terminated);
-	erts_smp_rwmtx_rlock(&erts_dist_table_rwmtx);
+        int i = 0;
+        Eterm *dist_ctrl;
+        DistEntry** pending;
+
+        ERTS_UNDEF(dist_ctrl, NULL);
+        ERTS_UNDEF(pending, NULL);
+
+	erts_rwmtx_rlock(&erts_dist_table_rwmtx);
 
-	for (tdep = erts_hidden_dist_entries; tdep; tdep = tdep->next)
-	    no_dist_port++;
-	for (tdep = erts_visible_dist_entries; tdep; tdep = tdep->next)
-	    no_dist_port++;
+        no_dist_ctrl = (erts_no_of_hidden_dist_entries +
+                        erts_no_of_visible_dist_entries);
+        no_pending = erts_no_of_pending_dist_entries;
 
 	/* KILL all port controllers */
-	if (no_dist_port == 0)
-	    erts_smp_rwmtx_runlock(&erts_dist_table_rwmtx);
-	else {
-	    Eterm def_buf[128];
-	    int i = 0;
-	    Eterm *dist_port;
-
-	    if (no_dist_port <= sizeof(def_buf)/sizeof(def_buf[0]))
-		dist_port = &def_buf[0];
-	    else
-		dist_port = erts_alloc(ERTS_ALC_T_TMP,
-				       sizeof(Eterm)*no_dist_port);
+	if (no_dist_ctrl) {
+            dist_ctrl = erts_alloc(ERTS_ALC_T_TMP,
+                                   sizeof(Eterm)*no_dist_ctrl);
 	    for (tdep = erts_hidden_dist_entries; tdep; tdep = tdep->next) {
-		ASSERT(is_internal_port(tdep->cid));
-		dist_port[i++] = tdep->cid;
+		ASSERT(is_internal_port(tdep->cid) || is_internal_pid(tdep->cid));
+                ASSERT(i < no_dist_ctrl);
+		dist_ctrl[i++] = tdep->cid;
 	    }
 	    for (tdep = erts_visible_dist_entries; tdep; tdep = tdep->next) {
-		ASSERT(is_internal_port(tdep->cid));
-		dist_port[i++] = tdep->cid;
+		ASSERT(is_internal_port(tdep->cid) || is_internal_pid(tdep->cid));
+                ASSERT(i < no_dist_ctrl);
+		dist_ctrl[i++] = tdep->cid;
 	    }
-	    erts_smp_rwmtx_runlock(&erts_dist_table_rwmtx);
-
-	    for (i = 0; i < no_dist_port; i++) {
-		Port *prt = erts_port_lookup(dist_port[i],
-					     ERTS_PORT_SFLGS_INVALID_LOOKUP);
-		if (!prt)
-		    continue;
-		ASSERT(erts_atomic32_read_nob(&prt->state)
-		       & ERTS_PORT_SFLG_DISTRIBUTION);
+            ASSERT(i == no_dist_ctrl);
+        }
+        if (no_pending) {
+            pending = erts_alloc(ERTS_ALC_T_TMP, sizeof(DistEntry*)*no_pending);
+            i = 0;
+            for (tdep = erts_pending_dist_entries; tdep; tdep = tdep->next) {
+                ASSERT(is_nil(tdep->cid));
+                ASSERT(i < no_pending);
+                pending[i++] = tdep;
+                erts_ref_dist_entry(tdep);
+            }
+            ASSERT(i == no_pending);
+        }
+        erts_rwmtx_runlock(&erts_dist_table_rwmtx);
+
+        if (no_dist_ctrl) {
+            for (i = 0; i < no_dist_ctrl; i++) {
+                if (is_internal_pid(dist_ctrl[i]))
+                    schedule_kill_dist_ctrl_proc(dist_ctrl[i]);
+                else {
+                    Port *prt = erts_port_lookup(dist_ctrl[i],
+                                                 ERTS_PORT_SFLGS_INVALID_LOOKUP);
+                    if (prt) {
+                        ASSERT(erts_atomic32_read_nob(&prt->state)
+                               & ERTS_PORT_SFLG_DISTRIBUTION);
+
+                        erts_port_exit(NULL, ERTS_PORT_SIG_FLG_FORCE_SCHED,
+                                       prt, dist_ctrl[i], nd_reason, NULL);
+                    }
+                }
+            }
+            erts_free(ERTS_ALC_T_TMP, dist_ctrl);
+        }
 
-		erts_port_exit(NULL, ERTS_PORT_SIG_FLG_FORCE_SCHED,
-			       prt, dist_port[i], nd_reason, NULL);
-	    }
+        if (no_pending) {
+            for (i = 0; i < no_pending; i++) {
+                abort_connection(pending[i], pending[i]->connection_id);
+                erts_deref_dist_entry(pending[i]);
+            }
+            erts_free(ERTS_ALC_T_TMP, pending);
+        }
 
-	    if (dist_port != &def_buf[0])
-		erts_free(ERTS_ALC_T_TMP, dist_port);
-	}
 
 	/*
-	 * When last dist port exits, node will be taken
+	 * When last dist ctrl exits, node will be taken
 	 * from alive to not alive.
 	 */
 	ASSERT(is_nil(nodedown.reason) && !nodedown.bp);
@@ -528,52 +571,51 @@ int erts_do_net_exits(DistEntry *dep, Eterm reason)
 					  &nodedown.bp->off_heap);
 	}
     }
-    else { /* Call from distribution port */
+    else { /* Call from distribution controller (port/process) */
 	NetExitsContext nec = {dep};
 	ErtsLink *nlinks;
 	ErtsLink *node_links;
 	ErtsMonitor *monitors;
 	Uint32 flags;
 
-	erts_smp_atomic_set_mb(&dep->dist_cmd_scheduled, 1);
-	erts_smp_de_rwlock(dep);
+	erts_atomic_set_mb(&dep->dist_cmd_scheduled, 1);
+	erts_de_rwlock(dep);
 
-	ERTS_SMP_LC_ASSERT(is_internal_port(dep->cid)
-			   && erts_lc_is_port_locked(erts_port_lookup_raw(dep->cid)));
+        if (is_internal_port(dep->cid)) {
+            ERTS_LC_ASSERT(erts_lc_is_port_locked(erts_port_lookup_raw(dep->cid)));
 
-	if (erts_port_task_is_scheduled(&dep->dist_cmd))
-	    erts_port_task_abort(&dep->dist_cmd);
+            if (erts_port_task_is_scheduled(&dep->dist_cmd))
+                erts_port_task_abort(&dep->dist_cmd);
+        }
 
 	if (dep->status & ERTS_DE_SFLG_EXITING) {
 #ifdef DEBUG
-	    erts_smp_mtx_lock(&dep->qlock);
-	    ASSERT(dep->qflgs & ERTS_DE_QFLG_EXIT);
-	    erts_smp_mtx_unlock(&dep->qlock);
+	    ASSERT(erts_atomic32_read_nob(&dep->qflgs) & ERTS_DE_QFLG_EXIT);
 #endif
 	}
 	else {
 	    dep->status |= ERTS_DE_SFLG_EXITING;
-	    erts_smp_mtx_lock(&dep->qlock);
-	    ASSERT(!(dep->qflgs & ERTS_DE_QFLG_EXIT));
-	    dep->qflgs |= ERTS_DE_QFLG_EXIT;
-	    erts_smp_mtx_unlock(&dep->qlock);
+	    erts_mtx_lock(&dep->qlock);
+	    ASSERT(!(erts_atomic32_read_nob(&dep->qflgs) & ERTS_DE_QFLG_EXIT));
+	    erts_atomic32_read_bor_relb(&dep->qflgs, ERTS_DE_QFLG_EXIT);
+	    erts_mtx_unlock(&dep->qlock);
 	}
 
-	erts_smp_de_links_lock(dep);
+	erts_de_links_lock(dep);
 	monitors	= dep->monitors;
         nlinks		= dep->nlinks;
 	node_links	= dep->node_links;
 	dep->monitors	= NULL;
         dep->nlinks	= NULL;
 	dep->node_links	= NULL;
-	erts_smp_de_links_unlock(dep);
+	erts_de_links_unlock(dep);
 
 	nodename = dep->sysname;
 	flags = dep->flags;
 
 	erts_set_dist_entry_not_connected(dep);
 
-	erts_smp_de_rwunlock(dep);
+	erts_de_rwunlock(dep);
 
 	erts_sweep_monitors(monitors, &doit_monitor_net_exits, (void *) &nec);
 	erts_sweep_links(nlinks, &doit_link_net_exits, (void *) &nec);
@@ -586,7 +628,6 @@ int erts_do_net_exits(DistEntry *dep, Eterm reason)
 			    reason == am_normal ? am_connection_closed : reason);
 
 	clear_dist_entry(dep);
-
     }
 
     dec_no_nodes();
@@ -607,19 +648,15 @@ void init_dist(void)
     nodedown.reason = NIL;
     nodedown.bp = NULL;
 
-    erts_smp_atomic_init_nob(&no_nodes, 0);
-    erts_smp_atomic_init_nob(&no_caches, 0);
+    erts_atomic_init_nob(&no_nodes, 0);
+    erts_atomic_init_nob(&no_caches, 0);
 
     /* Lookup/Install all references to trap functions */
-    dsend2_trap = trap_function(am_dsend,2);
-    dsend3_trap = trap_function(am_dsend,3);
-    /*    dsend_nosuspend_trap = trap_function(am_dsend_nosuspend,2);*/
-    dlink_trap = trap_function(am_dlink,1);
-    dunlink_trap = trap_function(am_dunlink,1);
     dmonitor_node_trap = trap_function(am_dmonitor_node,3);
-    dgroup_leader_trap = trap_function(am_dgroup_leader,2);
-    dexit_trap = trap_function(am_dexit, 2);
     dmonitor_p_trap = trap_function(am_dmonitor_p, 2);
+    dist_ctrl_put_data_trap = erts_export_put(am_erts_internal,
+                                              am_dist_ctrl_put_data,
+                                              2);
 }
 
 #define ErtsDistOutputBuf2Binary(OB) \
@@ -634,6 +671,7 @@ alloc_dist_obuf(Uint size)
     obuf = (ErtsDistOutputBuf *) &bin->orig_bytes[0];
 #ifdef DEBUG
     obuf->dbg_pattern = ERTS_DIST_OUTPUT_BUF_DBG_PATTERN;
+    obuf->alloc_endp = obuf->data + size;
     ASSERT(bin == ErtsDistOutputBuf2Binary(obuf));
 #endif
     return obuf;
@@ -654,26 +692,11 @@ size_obuf(ErtsDistOutputBuf *obuf)
     return bin->orig_size;
 }
 
-static void clear_dist_entry(DistEntry *dep)
+static ErtsDistOutputBuf* clear_de_out_queues(DistEntry* dep)
 {
-    Sint obufsize = 0;
-    ErtsAtomCache *cache;
-    ErtsProcList *suspendees;
     ErtsDistOutputBuf *obuf;
 
-    erts_smp_de_rwlock(dep);
-    cache = dep->cache;
-    dep->cache = NULL;
-
-#ifdef DEBUG
-    erts_smp_de_links_lock(dep);
-    ASSERT(!dep->nlinks);
-    ASSERT(!dep->node_links);
-    ASSERT(!dep->monitors);
-    erts_smp_de_links_unlock(dep);
-#endif
-
-    erts_smp_mtx_lock(&dep->qlock);
+    ERTS_LC_ASSERT(erts_lc_mtx_is_locked(&dep->qlock));
 
     if (!dep->out_queue.last)
 	obuf = dep->finalized_out_queue.first;
@@ -682,21 +705,24 @@ static void clear_dist_entry(DistEntry *dep)
 	obuf = dep->out_queue.first;
     }
 
+    if (dep->tmp_out_queue.first) {
+        dep->tmp_out_queue.last->next = obuf;
+        obuf = dep->tmp_out_queue.first;
+    }
+
     dep->out_queue.first = NULL;
     dep->out_queue.last = NULL;
+    dep->tmp_out_queue.first = NULL;
+    dep->tmp_out_queue.last = NULL;
     dep->finalized_out_queue.first = NULL;
     dep->finalized_out_queue.last = NULL;
-    dep->status = 0;
-    suspendees = get_suspended_on_de(dep, ERTS_DE_QFLGS_ALL);
-
-    erts_smp_mtx_unlock(&dep->qlock);
-    erts_smp_atomic_set_nob(&dep->dist_cmd_scheduled, 0);
-    dep->send = NULL;
-    erts_smp_de_rwunlock(dep);
 
-    erts_resume_processes(suspendees);
+    return obuf;
+}
 
-    delete_cache(cache);
+static void free_de_out_queues(DistEntry* dep, ErtsDistOutputBuf *obuf)
+{
+    Sint obufsize = 0;
 
     while (obuf) {
 	ErtsDistOutputBuf *fobuf;
@@ -707,13 +733,57 @@ static void clear_dist_entry(DistEntry *dep)
     }
 
     if (obufsize) {
-	erts_smp_mtx_lock(&dep->qlock);
-	ASSERT(dep->qsize >= obufsize);
-	dep->qsize -= obufsize;
-	erts_smp_mtx_unlock(&dep->qlock);
+	erts_mtx_lock(&dep->qlock);
+        ASSERT(erts_atomic_read_nob(&dep->qsize) >= obufsize);
+        erts_atomic_add_nob(&dep->qsize,
+                            (erts_aint_t) -obufsize);
+	erts_mtx_unlock(&dep->qlock);
     }
 }
 
+static void clear_dist_entry(DistEntry *dep)
+{
+    ErtsAtomCache *cache;
+    ErtsProcList *suspendees;
+    ErtsDistOutputBuf *obuf;
+
+    erts_de_rwlock(dep);
+    erts_atomic_set_nob(&dep->input_handler,
+                        (erts_aint_t) NIL);
+    cache = dep->cache;
+    dep->cache = NULL;
+
+#ifdef DEBUG
+    erts_de_links_lock(dep);
+    ASSERT(!dep->nlinks);
+    ASSERT(!dep->node_links);
+    ASSERT(!dep->monitors);
+    erts_de_links_unlock(dep);
+#endif
+
+    erts_mtx_lock(&dep->qlock);
+
+    erts_atomic64_set_nob(&dep->in, 0);
+    erts_atomic64_set_nob(&dep->out, 0);
+
+    obuf = clear_de_out_queues(dep);
+    dep->status = 0;
+    suspendees = get_suspended_on_de(dep, ERTS_DE_QFLGS_ALL);
+
+    erts_mtx_unlock(&dep->qlock);
+    erts_atomic_set_nob(&dep->dist_cmd_scheduled, 0);
+    dep->send = NULL;
+    erts_de_rwunlock(dep);
+
+    erts_resume_processes(suspendees);
+
+    delete_cache(cache);
+
+    free_de_out_queues(dep, obuf);
+    if (dep->transcode_ctx)
+        transcode_free_ctx(dep);
+}
+
 int erts_dsend_context_dtor(Binary* ctx_bin)
 {
     ErtsSendContext* ctx = ERTS_MAGIC_BIN_DATA(ctx_bin);
@@ -729,8 +799,8 @@ int erts_dsend_context_dtor(Binary* ctx_bin)
     if (ctx->dss.phase >= ERTS_DSIG_SEND_PHASE_ALLOC && ctx->dss.obuf) {
 	free_dist_obuf(ctx->dss.obuf);
     }
-    if (ctx->dep_to_deref)
-	erts_deref_dist_entry(ctx->dep_to_deref);
+    if (ctx->deref_dep)
+	erts_deref_dist_entry(ctx->dep);
 
     return 1;
 }
@@ -809,15 +879,22 @@ erts_dsig_send_m_exit(ErtsDSigData *dsdp, Eterm watcher, Eterm watched,
     DeclareTmpHeapNoproc(ctl_heap,6);
     int res;
 
+    if (~dsdp->dep->flags & (DFLAG_DIST_MONITOR | DFLAG_DIST_MONITOR_NAME)) {
+        /*
+         * Receiver does not support DOP_MONITOR_P_EXIT (see dsig_send_monitor)
+         */
+        return ERTS_DSIG_SEND_OK;
+    }
+
     UseTmpHeapNoproc(6);
 
     ctl = TUPLE5(&ctl_heap[0], make_small(DOP_MONITOR_P_EXIT),
 		 watched, watcher, ref, reason);
 
 #ifdef DEBUG
-    erts_smp_de_links_lock(dsdp->dep);
+    erts_de_links_lock(dsdp->dep);
     ASSERT(!erts_lookup_monitor(dsdp->dep->monitors, ref));
-    erts_smp_de_links_unlock(dsdp->dep);
+    erts_de_links_unlock(dsdp->dep);
 #endif
 
     res = dsig_send_ctl(dsdp, ctl, 1);
@@ -836,6 +913,16 @@ erts_dsig_send_monitor(ErtsDSigData *dsdp, Eterm watcher, Eterm watched,
     DeclareTmpHeapNoproc(ctl_heap,5);
     int res;
 
+    if (~dsdp->dep->flags & (DFLAG_DIST_MONITOR | DFLAG_DIST_MONITOR_NAME)) {
+        /*
+         * Receiver does not support DOP_MONITOR_P.
+         * Just avoid sending it and by doing that reduce this monitor
+         * to only supervise the connection. This will work for simple c-nodes
+         * with a 1-to-1 relation between "Erlang process" and OS-process.
+         */
+        return ERTS_DSIG_SEND_OK;
+    }
+
     UseTmpHeapNoproc(5);
     ctl = TUPLE4(&ctl_heap[0],
 		 make_small(DOP_MONITOR_P),
@@ -858,6 +945,13 @@ erts_dsig_send_demonitor(ErtsDSigData *dsdp, Eterm watcher,
     DeclareTmpHeapNoproc(ctl_heap,5);
     int res;
 
+    if (~dsdp->dep->flags & (DFLAG_DIST_MONITOR | DFLAG_DIST_MONITOR_NAME)) {
+        /*
+         * Receiver does not support DOP_DEMONITOR_P (see dsig_send_monitor)
+         */
+        return ERTS_DSIG_SEND_OK;
+    }
+
     UseTmpHeapNoproc(5);
     ctl = TUPLE4(&ctl_heap[0],
 		 make_small(DOP_DEMONITOR_P),
@@ -908,11 +1002,30 @@ erts_dsig_send_msg(Eterm remote, Eterm message, ErtsSendContext* ctx)
     }
 #endif
 
-    if (token != NIL)
-	ctl = TUPLE4(&ctx->ctl_heap[0],
-		     make_small(DOP_SEND_TT), am_Empty, remote, token);
-    else
-	ctl = TUPLE3(&ctx->ctl_heap[0], make_small(DOP_SEND), am_Empty, remote);
+    if (token != NIL) {
+        Eterm el1, el2;
+        if (ctx->dep->flags & DFLAG_SEND_SENDER) {
+            el1 = make_small(DOP_SEND_SENDER_TT);
+            el2 = sender->common.id;
+        }
+        else {
+            el1 = make_small(DOP_SEND_TT);
+            el2 = am_Empty;
+        }
+	ctl = TUPLE4(&ctx->ctl_heap[0], el1, el2, remote, token);
+    }
+    else {
+        Eterm el1, el2;
+        if (ctx->dep->flags & DFLAG_SEND_SENDER) {
+            el1 = make_small(DOP_SEND_SENDER);
+            el2 = sender->common.id;
+        }
+        else {
+            el1 = make_small(DOP_SEND);
+            el2 = am_Empty;
+        }
+	ctl = TUPLE3(&ctx->ctl_heap[0], el1, el2, remote);
+    }
     DTRACE6(message_send, sender_name, receiver_name,
             msize, tok_label, tok_lastcnt, tok_serial);
     DTRACE7(message_send_remote, sender_name, node_name, receiver_name,
@@ -1149,22 +1262,25 @@ int erts_net_message(Port *prt,
     ErtsLink *lnk;
     Uint tuple_arity;
     int res;
+    Uint32 connection_id;
 #ifdef ERTS_DIST_MSG_DBG
     ErlDrvSizeT orig_len = len;
 #endif
 
     UseTmpHeapNoproc(DIST_CTL_DEFAULT_SIZE);
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(!prt || erts_lc_is_port_locked(prt));
 
     if (!erts_is_alive) {
 	UnUseTmpHeapNoproc(DIST_CTL_DEFAULT_SIZE);
 	return 0;
     }
-    if (hlen != 0)
-	goto data_error;
+
+
+    ASSERT(hlen == 0);
+
     if (len == 0) {  /* HANDLE TICK !!! */
 	UnUseTmpHeapNoproc(DIST_CTL_DEFAULT_SIZE);
 	return 0;
@@ -1183,30 +1299,31 @@ int erts_net_message(Port *prt,
 	len--;
     }
 
-    if (len == 0) {
-	PURIFY_MSG("data error");
-	goto data_error;
-    }
+    res = erts_prepare_dist_ext(&ede, t, len, dep, dep->cache, &connection_id);
 
-    res = erts_prepare_dist_ext(&ede, t, len, dep, dep->cache);
-
-    if (res >= 0)
-	res = ctl_len = erts_decode_dist_ext_size(&ede);
-    else {
+    switch (res) {
+    case ERTS_PREP_DIST_EXT_CLOSED:
+        return 0; /* Connection not alive; ignore signal... */
+    case ERTS_PREP_DIST_EXT_FAILED:
 #ifdef ERTS_DIST_MSG_DBG
 	erts_fprintf(stderr, "DIST MSG DEBUG: erts_prepare_dist_ext() failed:\n");
 	bw(buf, orig_len);
 #endif
-	ctl_len = 0;
-    }
-
-    if (res < 0) {
+        goto data_error;
+    case ERTS_PREP_DIST_EXT_SUCCESS:
+	ctl_len = erts_decode_dist_ext_size(&ede);
+        if (ctl_len < 0) {
 #ifdef ERTS_DIST_MSG_DBG
-	erts_fprintf(stderr, "DIST MSG DEBUG: erts_decode_dist_ext_size(CTL) failed:\n");
-	bw(buf, orig_len);
+            erts_fprintf(stderr, "DIST MSG DEBUG: erts_decode_dist_ext_size(CTL) failed:\n");
+            bw(buf, orig_len);
 #endif
-	PURIFY_MSG("data error");
-	goto data_error;
+            PURIFY_MSG("data error");
+            goto data_error;
+        }
+        break;
+    default:
+        ERTS_INTERNAL_ERROR("Unexpected result from erts_prepare_dist_ext()");
+        break;
     }
 
     if (ctl_len > DIST_CTL_DEFAULT_SIZE) {
@@ -1237,6 +1354,7 @@ int erts_net_message(Port *prt,
     }
 
     token_size = 0;
+    token = NIL;
 
     switch (type = unsigned_val(tuple[1])) {
     case DOP_LINK:
@@ -1257,7 +1375,7 @@ int erts_net_message(Port *prt,
 	    /* This is tricky (we MUST force a distributed send) */
 	    ErtsDSigData dsd;
 	    int code;
-	    code = erts_dsig_prepare(&dsd, dep, NULL, ERTS_DSP_NO_LOCK, 0);
+	    code = erts_dsig_prepare(&dsd, dep, NULL, 0, ERTS_DSP_NO_LOCK, 0, 0);
 	    if (code == ERTS_DSIG_PREP_CONNECTED) {
 		code = erts_dsig_send_exit(&dsd, to, from, am_noproc);
 		ASSERT(code == ERTS_DSIG_SEND_OK);
@@ -1265,23 +1383,23 @@ int erts_net_message(Port *prt,
 	    break;
 	}
 
-	erts_smp_de_links_lock(dep);
+	erts_de_links_lock(dep);
 	res = erts_add_link(&ERTS_P_LINKS(rp), LINK_PID, from);
 
 	if (res < 0) {
 	    /* It was already there! Lets skip the rest... */
-	    erts_smp_de_links_unlock(dep);
-	    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	    erts_de_links_unlock(dep);
+	    erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 	    break;
 	}
 	lnk = erts_add_or_lookup_link(&(dep->nlinks), LINK_PID, rp->common.id);
 	erts_add_link(&(ERTS_LINK_ROOT(lnk)), LINK_PID, from);
-	erts_smp_de_links_unlock(dep);
+	erts_de_links_unlock(dep);
 
 	if (IS_TRACED_FL(rp, F_TRACE_PROCS))
 	    trace_proc(NULL, 0, rp, am_getting_linked, from);
 
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 	break;
 
     case DOP_UNLINK: {
@@ -1307,7 +1425,7 @@ int erts_net_message(Port *prt,
 	    trace_proc(NULL, 0, rp, am_getting_unlinked, from);
 	}
 
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 
 	erts_remove_dist_link(&dld, to, from, dep);
 	erts_destroy_dist_link(&dld);
@@ -1349,7 +1467,7 @@ int erts_net_message(Port *prt,
 	if (!rp) {
 	    ErtsDSigData dsd;
 	    int code;
-	    code = erts_dsig_prepare(&dsd, dep, NULL, ERTS_DSP_NO_LOCK, 0);
+	    code = erts_dsig_prepare(&dsd, dep, NULL, 0, ERTS_DSP_NO_LOCK, 0, 0);
 	    if (code == ERTS_DSIG_PREP_CONNECTED) {
 		code = erts_dsig_send_m_exit(&dsd, watcher, watched, ref,
 					     am_noproc);
@@ -1359,11 +1477,11 @@ int erts_net_message(Port *prt,
 	else {
 	    if (is_atom(watched))
 		watched = rp->common.id;
-	    erts_smp_de_links_lock(dep);
+	    erts_de_links_lock(dep);
 	    erts_add_monitor(&(dep->monitors), MON_ORIGIN, ref, watched, name);
 	    erts_add_monitor(&ERTS_P_MONITORS(rp), MON_TARGET, ref, watcher, name);
-	    erts_smp_de_links_unlock(dep);
-	    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	    erts_de_links_unlock(dep);
+	    erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 	}
 
 	break;
@@ -1385,9 +1503,9 @@ int erts_net_message(Port *prt,
 	    goto invalid_message;
 	}
 
-	erts_smp_de_links_lock(dep);
+	erts_de_links_lock(dep);
 	mon = erts_remove_monitor(&(dep->monitors),ref);
-	erts_smp_de_links_unlock(dep);
+	erts_de_links_unlock(dep);
 	/* ASSERT(mon != NULL); can happen in case of broken dist message */
 	if (mon == NULL) {
 	    break;
@@ -1401,7 +1519,7 @@ int erts_net_message(Port *prt,
 	    break;
 	}
 	mon = erts_remove_monitor(&ERTS_P_MONITORS(rp), ref);
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 	ASSERT(mon != NULL);
 	if (mon == NULL) {
 	    break;
@@ -1462,42 +1580,56 @@ int erts_net_message(Port *prt,
 
 	    erts_queue_dist_message(rp, locks, ede_copy, token, from);
 	    if (locks)
-		erts_smp_proc_unlock(rp, locks);
+		erts_proc_unlock(rp, locks);
 	}
 	break;
 
+    case DOP_SEND_SENDER_TT: {
+        Uint xsize;
     case DOP_SEND_TT:
+
 	if (tuple_arity != 4) {
 	    goto invalid_message;
 	}
-	
-	token_size = size_object(tuple[4]);
-	/* Fall through ... */
+
+	token = tuple[4];
+	token_size = size_object(token);
+        xsize = ERTS_HEAP_FRAG_SIZE(token_size);
+        goto send_common;
+
+    case DOP_SEND_SENDER:
     case DOP_SEND:
+
+        token = NIL;
+        xsize = 0;
+	if (tuple_arity != 3)
+	    goto invalid_message;
+
+    send_common:
+
 	/*
-	 * There is intentionally no testing of the cookie (it is always '')
-	 * from R9B and onwards.
+         * If DOP_SEND_SENDER or DOP_SEND_SENDER_TT element 2 contains
+         * the sender pid (i.e. DFLAG_SEND_SENDER is set); otherwise,
+         * the atom '' (empty cookie).
 	 */
+        ASSERT((type == DOP_SEND_SENDER || type == DOP_SEND_SENDER_TT)
+               ? (is_pid(tuple[2]) && (dep->flags & DFLAG_SEND_SENDER))
+               : tuple[2] == am_Empty);
+
 #ifdef ERTS_DIST_MSG_DBG
 	dist_msg_dbg(&ede, "MSG", buf, orig_len);
 #endif
-	if (type != DOP_SEND_TT && tuple_arity != 3) {
-	    goto invalid_message;
-	}
 	to = tuple[3];
 	if (is_not_pid(to)) {
 	    goto invalid_message;
 	}
 	rp = erts_proc_lookup(to);
 	if (rp) {
-	    Uint xsize = type == DOP_SEND ? 0 : ERTS_HEAP_FRAG_SIZE(token_size);
 	    ErtsProcLocks locks = 0;
 	    ErtsDistExternal *ede_copy;
 
 	    ede_copy = erts_make_dist_ext_copy(&ede, xsize);
-	    if (type == DOP_SEND) {
-		token = NIL;
-	    } else {
+	    if (is_not_nil(token)) {
 		ErlHeapFragment *heap_frag;
 		ErlOffHeap *ohp;
 		ASSERT(xsize);
@@ -1505,15 +1637,15 @@ int erts_net_message(Port *prt,
 		ERTS_INIT_HEAP_FRAG(heap_frag, token_size, token_size);
 		hp = heap_frag->mem;
 		ohp = &heap_frag->off_heap;
-		token = tuple[4];
 		token = copy_struct(token, token_size, &hp, ohp);
 	    }
 
-	    erts_queue_dist_message(rp, locks, ede_copy, token, tuple[2]);
+	    erts_queue_dist_message(rp, locks, ede_copy, token, am_Empty);
 	    if (locks)
-		erts_smp_proc_unlock(rp, locks);
+		erts_proc_unlock(rp, locks);
 	}
 	break;
+    }
 
     case DOP_MONITOR_P_EXIT: {
 	/* We are monitoring a process on the remote node which dies, we get
@@ -1537,7 +1669,7 @@ int erts_net_message(Port *prt,
 	    goto invalid_message;
 	}
 
-	erts_smp_de_links_lock(dep);
+	erts_de_links_lock(dep);
 	sysname = dep->sysname;
 	mon = erts_remove_monitor(&(dep->monitors), ref);
 	/*
@@ -1546,7 +1678,7 @@ int erts_net_message(Port *prt,
 	 * removed info about monitor. In this case, do nothing
 	 * and everything will be as it should.
 	 */
-	erts_smp_de_links_unlock(dep);
+	erts_de_links_unlock(dep);
 	if (mon == NULL) {
 	    break;
 	}
@@ -1560,7 +1692,7 @@ int erts_net_message(Port *prt,
 	mon = erts_remove_monitor(&ERTS_P_MONITORS(rp), ref);
 
 	if (mon == NULL) {
-	    erts_smp_proc_unlock(rp, rp_locks);
+	    erts_proc_unlock(rp, rp_locks);
 	    break;
 	}
 	UseTmpHeapNoproc(3);
@@ -1571,7 +1703,7 @@ int erts_net_message(Port *prt,
 	
 	erts_queue_monitor_message(rp, &rp_locks,
 				   ref, am_process, watched, reason);
-	erts_smp_proc_unlock(rp, rp_locks);
+	erts_proc_unlock(rp, rp_locks);
 	erts_destroy_monitor(mon);
 	UnUseTmpHeapNoproc(3);
 	break;
@@ -1633,13 +1765,13 @@ int erts_net_message(Port *prt,
 		if (xres >= 0 && IS_TRACED_FL(rp, F_TRACE_PROCS)) {
 		    /* We didn't exit the process and it is traced */
                     if (rp_locks & ERTS_PROC_LOCKS_XSIG_SEND) {
-                        erts_smp_proc_unlock(rp, ERTS_PROC_LOCKS_XSIG_SEND);
+                        erts_proc_unlock(rp, ERTS_PROC_LOCKS_XSIG_SEND);
                         rp_locks &= ~ERTS_PROC_LOCKS_XSIG_SEND;
                     }
 		    trace_proc(NULL, 0, rp, am_getting_unlinked, from);
 		}
 	    }
-	    erts_smp_proc_unlock(rp, rp_locks);
+	    erts_proc_unlock(rp, rp_locks);
 	}
 	erts_remove_dist_link(&dld, to, from, dep);
 	if (lnk)
@@ -1681,7 +1813,7 @@ int erts_net_message(Port *prt,
 					 token,
 					 NULL,
 					 0);
-	    erts_smp_proc_unlock(rp, rp_locks);
+	    erts_proc_unlock(rp, rp_locks);
 	}
 	break;
     }
@@ -1699,7 +1831,7 @@ int erts_net_message(Port *prt,
 	if (!rp)
 	    break;
 	rp->group_leader = STORE_NC_IN_PROC(rp, from);
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_MAIN);
 	break;
 
     default: 
@@ -1711,7 +1843,7 @@ int erts_net_message(Port *prt,
 	erts_free(ERTS_ALC_T_DCTRL_BUF, (void *) ctl);
     }
     UnUseTmpHeapNoproc(DIST_CTL_DEFAULT_SIZE);
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     return 0;
  invalid_message:
     {
@@ -1727,8 +1859,8 @@ decode_error:
     }
 data_error:
     UnUseTmpHeapNoproc(DIST_CTL_DEFAULT_SIZE);
-    erts_deliver_port_exit(prt, dep->cid, am_killed, 0, 1);
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    erts_kill_dist_connection(dep, connection_id);
+    ERTS_CHK_NO_PROC_LOCKS;
     return -1;
 }
 
@@ -1748,6 +1880,31 @@ static int dsig_send_ctl(ErtsDSigData* dsdp, Eterm ctl, int force_busy)
     return ret;
 }
 
+static ERTS_INLINE void
+notify_dist_data(Process *c_p, Eterm pid)
+{
+    Process *rp;
+    ErtsProcLocks rp_locks;
+
+    ASSERT(erts_get_scheduler_data()
+           && !ERTS_SCHEDULER_IS_DIRTY(erts_get_scheduler_data()));
+    ASSERT(is_internal_pid(pid));
+
+    if (c_p && c_p->common.id == pid) {
+        rp = c_p;
+        rp_locks = ERTS_PROC_LOCK_MAIN;
+    }
+    else {
+        rp = erts_proc_lookup(pid);
+        rp_locks = 0;
+    }
+
+    if (rp) {
+        ErtsMessage *mp = erts_alloc_message(0, NULL);
+        erts_queue_message(rp, rp_locks, mp, am_dist_data, am_system);
+    }
+}
+
 int
 erts_dsig_send(ErtsDSigData *dsdp, struct erts_dsig_send_context* ctx)
 {
@@ -1764,7 +1921,7 @@ erts_dsig_send(ErtsDSigData *dsdp, struct erts_dsig_send_context* ctx)
 	    if (!ctx->c_p || dsdp->no_suspend)
 		ctx->force_busy = 1;
 
-	    ERTS_SMP_LC_ASSERT(!ctx->c_p
+	    ERTS_LC_ASSERT(!ctx->c_p
 			       || (ERTS_PROC_LOCK_MAIN
 				   == erts_proc_lc_my_proc_locks(ctx->c_p)));
 
@@ -1773,33 +1930,32 @@ erts_dsig_send(ErtsDSigData *dsdp, struct erts_dsig_send_context* ctx)
 
 	    if (ctx->flags & DFLAG_DIST_HDR_ATOM_CACHE) {
 		ctx->acmp = erts_get_atom_cache_map(ctx->c_p);
-		ctx->pass_through_size = 0;
+		ctx->max_finalize_prepend = 0;
 	    }
 	    else {
 		ctx->acmp = NULL;
-		ctx->pass_through_size = 1;
+		ctx->max_finalize_prepend = 3;
 	    }
 
     #ifdef ERTS_DIST_MSG_DBG
-	    erts_fprintf(stderr, ">>%s CTL: %T\n", ctx->pass_through_size ? "P" : " ", ctx->ctl);
-        if (is_value(ctx->msg))
-            erts_fprintf(stderr, "    MSG: %T\n", ctx->msg);
+            erts_fprintf(stderr, ">> CTL: %T\n", ctx->ctl);
+            if (is_value(ctx->msg))
+                erts_fprintf(stderr, "    MSG: %T\n", ctx->msg);
     #endif
 
-	    ctx->data_size = ctx->pass_through_size;
+	    ctx->data_size = ctx->max_finalize_prepend;
 	    erts_reset_atom_cache_map(ctx->acmp);
 	    erts_encode_dist_ext_size(ctx->ctl, ctx->flags, ctx->acmp, &ctx->data_size);
 
-	    if (is_value(ctx->msg)) {
-		ctx->u.sc.wstack.wstart = NULL;
-		ctx->u.sc.flags = ctx->flags;
-		ctx->u.sc.level = 0;
-		ctx->phase = ERTS_DSIG_SEND_PHASE_MSG_SIZE;
-	    } else {
-		ctx->phase = ERTS_DSIG_SEND_PHASE_ALLOC;
-	    }
-	    break;
+	    if (is_non_value(ctx->msg)) {
+                ctx->phase = ERTS_DSIG_SEND_PHASE_ALLOC;
+                break;
+            }
+            ctx->u.sc.wstack.wstart = NULL;
+            ctx->u.sc.flags = ctx->flags;
+            ctx->u.sc.level = 0;
 
+            ctx->phase = ERTS_DSIG_SEND_PHASE_MSG_SIZE;
 	case ERTS_DSIG_SEND_PHASE_MSG_SIZE:
 	    if (erts_encode_dist_ext_size_int(ctx->msg, ctx, &ctx->data_size)) {
 		retval = ERTS_DSIG_SEND_CONTINUE;
@@ -1814,23 +1970,24 @@ erts_dsig_send(ErtsDSigData *dsdp, struct erts_dsig_send_context* ctx)
 	    ctx->data_size += ctx->dhdr_ext_size;
 
 	    ctx->obuf = alloc_dist_obuf(ctx->data_size);
-	    ctx->obuf->ext_endp = &ctx->obuf->data[0] + ctx->pass_through_size + ctx->dhdr_ext_size;
+	    ctx->obuf->ext_endp = &ctx->obuf->data[0] + ctx->max_finalize_prepend + ctx->dhdr_ext_size;
 
 	    /* Encode internal version of dist header */
 	    ctx->obuf->extp = erts_encode_ext_dist_header_setup(ctx->obuf->ext_endp, ctx->acmp);
 	    /* Encode control message */
 	    erts_encode_dist_ext(ctx->ctl, &ctx->obuf->ext_endp, ctx->flags, ctx->acmp, NULL, NULL);
-	    if (is_value(ctx->msg)) {
-		ctx->u.ec.flags = ctx->flags;
-		ctx->u.ec.level = 0;
-		ctx->u.ec.wstack.wstart = NULL;
-		ctx->phase = ERTS_DSIG_SEND_PHASE_MSG_ENCODE;
-	    } else {
-		ctx->phase = ERTS_DSIG_SEND_PHASE_FIN;
-	    }
-	    break;
+	    if (is_non_value(ctx->msg)) {
+                ctx->obuf->msg_start = NULL;
+                ctx->phase = ERTS_DSIG_SEND_PHASE_FIN;
+                break;
+            }
+            ctx->u.ec.flags = ctx->flags;
+            ctx->u.ec.level = 0;
+            ctx->u.ec.wstack.wstart = NULL;
+            ctx->obuf->msg_start = ctx->obuf->ext_endp;
 
-	case ERTS_DSIG_SEND_PHASE_MSG_ENCODE:
+            ctx->phase = ERTS_DSIG_SEND_PHASE_MSG_ENCODE;
+        case ERTS_DSIG_SEND_PHASE_MSG_ENCODE:
 	    if (erts_encode_dist_ext(ctx->msg, &ctx->obuf->ext_endp, ctx->flags, ctx->acmp, &ctx->u.ec, &ctx->reds)) {
 		retval = ERTS_DSIG_SEND_CONTINUE;
 		goto done;
@@ -1843,7 +2000,7 @@ erts_dsig_send(ErtsDSigData *dsdp, struct erts_dsig_send_context* ctx)
 	    int resume = 0;
 
 	    ASSERT(ctx->obuf->extp < ctx->obuf->ext_endp);
-	    ASSERT(&ctx->obuf->data[0] <= ctx->obuf->extp - ctx->pass_through_size);
+	    ASSERT(&ctx->obuf->data[0] <= ctx->obuf->extp - ctx->max_finalize_prepend);
 	    ASSERT(ctx->obuf->ext_endp <= &ctx->obuf->data[0] + ctx->data_size);
 
 	    ctx->data_size = ctx->obuf->ext_endp - ctx->obuf->extp;
@@ -1853,28 +2010,48 @@ erts_dsig_send(ErtsDSigData *dsdp, struct erts_dsig_send_context* ctx)
 	     * and if so enqueue the signal and schedule it for send.
 	     */
 	    ctx->obuf->next = NULL;
-	    erts_smp_de_rlock(dep);
+	    erts_de_rlock(dep);
 	    cid = dep->cid;
-	    if (cid != dsdp->cid
-		|| dep->connection_id != dsdp->connection_id
-		|| dep->status & ERTS_DE_SFLG_EXITING) {
+	    if (!(dep->status & (ERTS_DE_SFLG_PENDING | ERTS_DE_SFLG_CONNECTED))
+                || dep->status & ERTS_DE_SFLG_EXITING
+                || dep->connection_id != dsdp->connection_id) {
 		/* Not the same connection as when we started; drop message... */
-		erts_smp_de_runlock(dep);
+		erts_de_runlock(dep);
 		free_dist_obuf(ctx->obuf);
 	    }
 	    else {
+                Sint qsize;
+                erts_aint32_t qflgs;
 		ErtsProcList *plp = NULL;
-		erts_smp_mtx_lock(&dep->qlock);
-		dep->qsize += size_obuf(ctx->obuf);
-		if (dep->qsize >= erts_dist_buf_busy_limit)
-		    dep->qflgs |= ERTS_DE_QFLG_BUSY;
-		if (!ctx->force_busy && (dep->qflgs & ERTS_DE_QFLG_BUSY)) {
-		    erts_smp_mtx_unlock(&dep->qlock);
+                Eterm notify_proc = NIL;
+                Sint obsz = size_obuf(ctx->obuf);
+
+		erts_mtx_lock(&dep->qlock);
+		qsize = erts_atomic_add_read_nob(&dep->qsize, (erts_aint_t) obsz);
+                ASSERT(qsize >= obsz);
+                qflgs = erts_atomic32_read_nob(&dep->qflgs);
+		if (!(qflgs & ERTS_DE_QFLG_BUSY) && qsize >= erts_dist_buf_busy_limit) {
+		    erts_atomic32_read_bor_relb(&dep->qflgs, ERTS_DE_QFLG_BUSY);
+                    qflgs |= ERTS_DE_QFLG_BUSY;
+                }
+                if (qsize == obsz && (qflgs & ERTS_DE_QFLG_REQ_INFO)) {
+                    /* Previously empty queue and info requested... */
+                    qflgs = erts_atomic32_read_band_mb(&dep->qflgs,
+                                                       ~ERTS_DE_QFLG_REQ_INFO);
+                    if (qflgs & ERTS_DE_QFLG_REQ_INFO) {
+                        notify_proc = dep->cid;
+                        ASSERT(is_internal_pid(notify_proc));
+                    }
+                    /* else: requester will send itself the message... */
+                    qflgs &= ~ERTS_DE_QFLG_REQ_INFO;
+                }
+		if (!ctx->force_busy && (qflgs & ERTS_DE_QFLG_BUSY)) {
+		    erts_mtx_unlock(&dep->qlock);
 
 		    plp = erts_proclist_create(ctx->c_p);
 		    erts_suspend(ctx->c_p, ERTS_PROC_LOCK_MAIN, NULL);
 		    suspended = 1;
-		    erts_smp_mtx_lock(&dep->qlock);
+		    erts_mtx_lock(&dep->qlock);
 		}
 
 		/* Enqueue obuf on dist entry */
@@ -1885,7 +2062,8 @@ erts_dsig_send(ErtsDSigData *dsdp, struct erts_dsig_send_context* ctx)
 		dep->out_queue.last = ctx->obuf;
 
 		if (!ctx->force_busy) {
-		    if (!(dep->qflgs & ERTS_DE_QFLG_BUSY)) {
+                    qflgs = erts_atomic32_read_nob(&dep->qflgs);
+		    if (!(qflgs & ERTS_DE_QFLG_BUSY)) {
 			if (suspended)
 			    resume = 1; /* was busy when we started, but isn't now */
     #ifdef USE_VM_PROBES
@@ -1909,9 +2087,17 @@ erts_dsig_send(ErtsDSigData *dsdp, struct erts_dsig_send_context* ctx)
 		    }
 		}
 
-		erts_smp_mtx_unlock(&dep->qlock);
-		erts_schedule_dist_command(NULL, dep);
-		erts_smp_de_runlock(dep);
+		erts_mtx_unlock(&dep->qlock);
+		if (!(dep->status & ERTS_DE_SFLG_PENDING)) {
+                    if (is_internal_port(dep->cid))
+                        erts_schedule_dist_command(NULL, dep);
+                }
+                else {
+                    notify_proc = NIL;
+                }
+		erts_de_runlock(dep);
+                if (is_internal_pid(notify_proc))
+                    notify_dist_data(ctx->c_p, notify_proc);
 
 		if (resume) {
 		    erts_resume(ctx->c_p, ERTS_PROC_LOCK_MAIN);
@@ -1965,16 +2151,20 @@ static Uint
 dist_port_command(Port *prt, ErtsDistOutputBuf *obuf)
 {
     int fpe_was_unmasked;
-    Uint size = obuf->ext_endp - obuf->extp;
+    ErlDrvSizeT size;
+    char *bufp;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_CHK_NO_PROC_LOCKS;
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
-    if (size > (Uint) INT_MAX)
-	erts_exit(ERTS_DUMP_EXIT,
-		 "Absurdly large distribution output data buffer "
-		 "(%beu bytes) passed.\n",
-		 size);
+    if (!obuf) {
+        size = 0;
+        bufp = NULL;
+    }
+    else {
+        size = obuf->ext_endp - obuf->extp;
+        bufp = (char*) obuf->extp;
+    }
 
 #ifdef USE_VM_PROBES
     if (DTRACE_ENABLED(dist_output)) {
@@ -1989,11 +2179,10 @@ dist_port_command(Port *prt, ErtsDistOutputBuf *obuf)
                 remote_str, size);
     }
 #endif
+
     prt->caller = NIL;
     fpe_was_unmasked = erts_block_fpe();
-    (*prt->drv_ptr->output)((ErlDrvData) prt->drv_data,
-			    (char*) obuf->extp,
-			    (int) size);
+    (*prt->drv_ptr->output)((ErlDrvData) prt->drv_data, bufp, size);
     erts_unblock_fpe(fpe_was_unmasked);
     return size;
 }
@@ -2002,33 +2191,41 @@ static Uint
 dist_port_commandv(Port *prt, ErtsDistOutputBuf *obuf)
 {
     int fpe_was_unmasked;
-    Uint size = obuf->ext_endp - obuf->extp;
+    ErlDrvSizeT size;
     SysIOVec iov[2];
     ErlDrvBinary* bv[2];
     ErlIOVec eiov;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
-
-    if (size > (Uint) INT_MAX)
-	erts_exit(ERTS_DUMP_EXIT,
-		 "Absurdly large distribution output data buffer "
-		 "(%beu bytes) passed.\n",
-		 size);
+    ERTS_CHK_NO_PROC_LOCKS;
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
     iov[0].iov_base = NULL;
     iov[0].iov_len = 0;
     bv[0] = NULL;
 
-    iov[1].iov_base = obuf->extp;
-    iov[1].iov_len = size;
-    bv[1] = Binary2ErlDrvBinary(ErtsDistOutputBuf2Binary(obuf));
+    if (!obuf) {
+        size = 0;
+        eiov.vsize = 1;
+    }
+    else {
+        size = obuf->ext_endp - obuf->extp;
+        eiov.vsize = 2;
+
+        iov[1].iov_base = obuf->extp;
+        iov[1].iov_len = size;
+        bv[1] = Binary2ErlDrvBinary(ErtsDistOutputBuf2Binary(obuf));
+    }
 
-    eiov.vsize = 2;
     eiov.size = size;
     eiov.iov = iov;
     eiov.binv = bv;
 
+    if (size > (Uint) INT_MAX)
+	erts_exit(ERTS_DUMP_EXIT,
+		 "Absurdly large distribution output data buffer "
+		 "(%beu bytes) passed.\n",
+		 size);
+
     ASSERT(prt->drv_ptr->outputv);
 
 #ifdef USE_VM_PROBES
@@ -2062,7 +2259,6 @@ dist_port_commandv(Port *prt, ErtsDistOutputBuf *obuf)
 #endif
 
 #define ERTS_PORT_REDS_DIST_CMD_START 5
-#define ERTS_PORT_REDS_DIST_CMD_FINALIZE 3
 #define ERTS_PORT_REDS_DIST_CMD_EXIT 200
 #define ERTS_PORT_REDS_DIST_CMD_RESUMED 5
 #define ERTS_PORT_REDS_DIST_CMD_DATA(SZ) \
@@ -2071,37 +2267,36 @@ dist_port_commandv(Port *prt, ErtsDistOutputBuf *obuf)
    : ((((Sint) (SZ)) >> 10) & ((Sint) ERTS_PORT_REDS_MASK__)))
 
 int
-erts_dist_command(Port *prt, int reds_limit)
+erts_dist_command(Port *prt, int initial_reds)
 {
-    Sint reds = ERTS_PORT_REDS_DIST_CMD_START;
+    Sint reds = initial_reds - ERTS_PORT_REDS_DIST_CMD_START;
     Uint32 status;
     Uint32 flags;
-    Sint obufsize = 0;
+    Sint qsize, obufsize = 0;
     ErtsDistOutputQueue oq, foq;
     DistEntry *dep = prt->dist_entry;
     Uint (*send)(Port *prt, ErtsDistOutputBuf *obuf);
     erts_aint32_t sched_flags;
     ErtsSchedulerData *esdp = erts_get_scheduler_data();
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
-
-    erts_smp_refc_inc(&dep->refc, 1); /* Otherwise dist_entry might be
-				     removed if port command fails */
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
-    erts_smp_atomic_set_mb(&dep->dist_cmd_scheduled, 0);
+    erts_atomic_set_mb(&dep->dist_cmd_scheduled, 0);
 
-    erts_smp_de_rlock(dep);
+    erts_de_rlock(dep);
     flags = dep->flags;
     status = dep->status;
     send = dep->send;
-    erts_smp_de_runlock(dep);
+    erts_de_runlock(dep);
 
     if (status & ERTS_DE_SFLG_EXITING) {
 	erts_deliver_port_exit(prt, prt->common.id, am_killed, 0, 1);
-	erts_deref_dist_entry(dep);
-	return reds + ERTS_PORT_REDS_DIST_CMD_EXIT;
+        reds -= ERTS_PORT_REDS_DIST_CMD_EXIT;
+	return initial_reds - reds;
     }
 
+    ASSERT(!(status & ERTS_DE_SFLG_PENDING));
+
     ASSERT(send);
 
     /*
@@ -2112,42 +2307,42 @@ erts_dist_command(Port *prt, int reds_limit)
      * a mess.
      */
 
-    erts_smp_mtx_lock(&dep->qlock);
+    erts_mtx_lock(&dep->qlock);
     oq.first = dep->out_queue.first;
     oq.last = dep->out_queue.last;
     dep->out_queue.first = NULL;
     dep->out_queue.last = NULL;
-    erts_smp_mtx_unlock(&dep->qlock);
+    erts_mtx_unlock(&dep->qlock);
 
     foq.first = dep->finalized_out_queue.first;
     foq.last = dep->finalized_out_queue.last;
     dep->finalized_out_queue.first = NULL;
     dep->finalized_out_queue.last = NULL;
 
-    sched_flags = erts_smp_atomic32_read_nob(&prt->sched.flags);
+    sched_flags = erts_atomic32_read_nob(&prt->sched.flags);
 
-    if (reds > reds_limit)
+    if (reds < 0)
 	goto preempted;
 
     if (!(sched_flags & ERTS_PTS_FLG_BUSY_PORT) && foq.first) {
 	int preempt = 0;
 	do {
-	    Uint size;
-	    ErtsDistOutputBuf *fob;
-
-	    size = (*send)(prt, foq.first);
-	    esdp->io.out += (Uint64) size;
+            Uint size;
+            ErtsDistOutputBuf *fob;
+            size = (*send)(prt, foq.first);
+            erts_atomic64_inc_nob(&dep->out);
+            esdp->io.out += (Uint64) size;
 #ifdef ERTS_RAW_DIST_MSG_DBG
-	    erts_fprintf(stderr, ">> ");
-	    bw(foq.first->extp, size);
+            erts_fprintf(stderr, ">> ");
+            bw(foq.first->extp, size);
 #endif
-	    reds += ERTS_PORT_REDS_DIST_CMD_DATA(size);
+	    reds -= ERTS_PORT_REDS_DIST_CMD_DATA(size);
 	    fob = foq.first;
 	    obufsize += size_obuf(fob);
 	    foq.first = foq.first->next;
 	    free_dist_obuf(fob);
-	    sched_flags = erts_smp_atomic32_read_nob(&prt->sched.flags);
-	    preempt = reds > reds_limit || (sched_flags & ERTS_PTS_FLG_EXIT);
+	    sched_flags = erts_atomic32_read_nob(&prt->sched.flags);
+	    preempt = reds < 0 || (sched_flags & ERTS_PTS_FLG_EXIT);
 	    if (sched_flags & ERTS_PTS_FLG_BUSY_PORT)
 		break;
 	} while (foq.first && !preempt);
@@ -2160,79 +2355,71 @@ erts_dist_command(Port *prt, int reds_limit)
     if (sched_flags & ERTS_PTS_FLG_BUSY_PORT) {
 	if (oq.first) {
 	    ErtsDistOutputBuf *ob;
-	    int preempt;
+            ErtsDistOutputBuf *last_finalized = NULL;
 	finalize_only:
-	    preempt = 0;
 	    ob = oq.first;
 	    ASSERT(ob);
 	    do {
-		ob->extp = erts_encode_ext_dist_header_finalize(ob->extp,
-								dep->cache,
-								flags);
-		if (!(flags & DFLAG_DIST_HDR_ATOM_CACHE))
-		    *--ob->extp = PASS_THROUGH; /* Old node; 'pass through'
-						   needed */
-		ASSERT(&ob->data[0] <= ob->extp && ob->extp < ob->ext_endp);
-		reds += ERTS_PORT_REDS_DIST_CMD_FINALIZE;
-		preempt = reds > reds_limit;
-		if (preempt)
-		    break;
-		ob = ob->next;
+		reds = erts_encode_ext_dist_header_finalize(ob, dep, flags, reds);
+                if (reds < 0)
+                    break;
+                last_finalized  = ob;
+                ob = ob->next;
 	    } while (ob);
-	    /*
-	     * At least one buffer was finalized; if we got preempted,
-	     * ob points to the last buffer that we finalized.
-	     */
-	    if (foq.last)
-		foq.last->next = oq.first;
-	    else
-		foq.first = oq.first;
-	    if (!preempt) {
-		/* All buffers finalized */
-		foq.last = oq.last;
-		oq.first = oq.last = NULL;
-	    }
-	    else {
-		/* Not all buffers finalized; split oq. */
-		foq.last = ob;
-		oq.first = ob->next;
-		if (oq.first)
-		    ob->next = NULL;
-		else
-		    oq.last = NULL;
-	    }
-	    if (preempt)
-		goto preempted;
+            if (last_finalized) {
+                /*
+                 * At least one buffer was finalized; if we got preempted,
+                 * ob points to the next buffer to continue finalize.
+                 */
+                if (foq.last)
+                    foq.last->next = oq.first;
+                else
+                    foq.first = oq.first;
+                foq.last = last_finalized;
+                if (!ob) {
+                    /* All buffers finalized */
+                    ASSERT(foq.last == oq.last);
+                    ASSERT(foq.last->next == NULL);
+                    oq.first = oq.last = NULL;
+                }
+                else {
+                    /* Not all buffers finalized; split oq. */
+                    ASSERT(foq.last->next == ob);
+                    foq.last->next = NULL;
+                    oq.first = ob;
+                }
+            }
+            if (reds <= 0)
+                goto preempted;
 	}
     }
     else {
+        int de_busy;
 	int preempt = 0;
 	while (oq.first && !preempt) {
 	    ErtsDistOutputBuf *fob;
 	    Uint size;
-	    oq.first->extp
-		= erts_encode_ext_dist_header_finalize(oq.first->extp,
-						       dep->cache,
-						       flags);
-	    reds += ERTS_PORT_REDS_DIST_CMD_FINALIZE;
-	    if (!(flags & DFLAG_DIST_HDR_ATOM_CACHE))
-		*--oq.first->extp = PASS_THROUGH; /* Old node; 'pass through'
-						     needed */
+            reds = erts_encode_ext_dist_header_finalize(oq.first, dep, flags, reds);
+            if (reds < 0) {
+                preempt = 1;
+                break;
+            }
 	    ASSERT(&oq.first->data[0] <= oq.first->extp
-		   && oq.first->extp < oq.first->ext_endp);
+		   && oq.first->extp <= oq.first->ext_endp);
 	    size = (*send)(prt, oq.first);
+            erts_atomic64_inc_nob(&dep->out);
 	    esdp->io.out += (Uint64) size;
 #ifdef ERTS_RAW_DIST_MSG_DBG
-	    erts_fprintf(stderr, ">> ");
-	    bw(oq.first->extp, size);
+            erts_fprintf(stderr, ">> ");
+            bw(oq.first->extp, size);
 #endif
-	    reds += ERTS_PORT_REDS_DIST_CMD_DATA(size);
+	    reds -= ERTS_PORT_REDS_DIST_CMD_DATA(size);
 	    fob = oq.first;
 	    obufsize += size_obuf(fob);
 	    oq.first = oq.first->next;
 	    free_dist_obuf(fob);
-	    sched_flags = erts_smp_atomic32_read_nob(&prt->sched.flags);
-	    preempt = reds > reds_limit || (sched_flags & ERTS_PTS_FLG_EXIT);
+	    sched_flags = erts_atomic32_read_nob(&prt->sched.flags);
+	    preempt = reds <= 0 || (sched_flags & ERTS_PTS_FLG_EXIT);
 	    if ((sched_flags & ERTS_PTS_FLG_BUSY_PORT) && oq.first && !preempt)
 		goto finalize_only;
 	}
@@ -2258,23 +2445,24 @@ erts_dist_command(Port *prt, int reds_limit)
 	 * dist entry in a non-busy state and resume suspended
 	 * processes.
 	 */
-	erts_smp_mtx_lock(&dep->qlock);
-	ASSERT(dep->qsize >= obufsize);
-	dep->qsize -= obufsize;
+	erts_mtx_lock(&dep->qlock);
+        de_busy = !!(erts_atomic32_read_nob(&dep->qflgs) & ERTS_DE_QFLG_BUSY);
+        qsize = (Sint) erts_atomic_add_read_nob(&dep->qsize,
+                                                (erts_aint_t) -obufsize);
+	ASSERT(qsize >= 0);
 	obufsize = 0;
 	if (!(sched_flags & ERTS_PTS_FLG_BUSY_PORT)
-	    && (dep->qflgs & ERTS_DE_QFLG_BUSY)
-	    && dep->qsize < erts_dist_buf_busy_limit) {
+	    && de_busy && qsize < erts_dist_buf_busy_limit) {
 	    ErtsProcList *suspendees;
 	    int resumed;
 	    suspendees = get_suspended_on_de(dep, ERTS_DE_QFLG_BUSY);
-	    erts_smp_mtx_unlock(&dep->qlock);
+	    erts_mtx_unlock(&dep->qlock);
 
 	    resumed = erts_resume_processes(suspendees);
-	    reds += resumed*ERTS_PORT_REDS_DIST_CMD_RESUMED;
+	    reds -= resumed*ERTS_PORT_REDS_DIST_CMD_RESUMED;
 	}
 	else
-	    erts_smp_mtx_unlock(&dep->qlock);
+	    erts_mtx_unlock(&dep->qlock);
     }
 
     ASSERT(!oq.first && !oq.last);
@@ -2283,14 +2471,18 @@ erts_dist_command(Port *prt, int reds_limit)
 
     if (obufsize != 0) {
 	ASSERT(obufsize > 0);
-	erts_smp_mtx_lock(&dep->qlock);
-	ASSERT(dep->qsize >= obufsize);
-	dep->qsize -= obufsize;
-	erts_smp_mtx_unlock(&dep->qlock);
+	erts_mtx_lock(&dep->qlock);
+#ifdef DEBUG
+        qsize = (Sint) erts_atomic_add_read_nob(&dep->qsize,
+                                                (erts_aint_t) -obufsize);
+	ASSERT(qsize >= 0);
+#else
+        erts_atomic_add_nob(&dep->qsize, (erts_aint_t) -obufsize);
+#endif
+	erts_mtx_unlock(&dep->qlock);
     }
 
-    ASSERT(foq.first || !foq.last);
-    ASSERT(!foq.first || foq.last);
+    ASSERT(!!foq.first == !!foq.last);
     ASSERT(!dep->finalized_out_queue.first);
     ASSERT(!dep->finalized_out_queue.last);
 
@@ -2300,12 +2492,10 @@ erts_dist_command(Port *prt, int reds_limit)
     }
 
      /* Avoid wrapping reduction counter... */
-    if (reds > INT_MAX/2)
-	reds = INT_MAX/2;
-
-    erts_deref_dist_entry(dep);
+    if (reds < INT_MIN/2)
+	reds = INT_MIN/2;
 
-    return reds;
+    return initial_reds - reds;
 
  preempted:
     /*
@@ -2313,8 +2503,7 @@ erts_dist_command(Port *prt, int reds_limit)
      * since last call to driver.
      */
 
-    ASSERT(oq.first || !oq.last);
-    ASSERT(!oq.first || oq.last);
+    ASSERT(!!oq.first == !!oq.last);
 
     if (sched_flags & ERTS_PTS_FLG_EXIT) {
 	/*
@@ -2338,12 +2527,6 @@ erts_dist_command(Port *prt, int reds_limit)
 
 	foq.first = NULL;
 	foq.last = NULL;
-
-#ifdef DEBUG
-	erts_smp_mtx_lock(&dep->qlock);
-	ASSERT(dep->qsize == obufsize);
-	erts_smp_mtx_unlock(&dep->qlock);
-#endif
     }
     else {
 	if (oq.first) {
@@ -2351,14 +2534,14 @@ erts_dist_command(Port *prt, int reds_limit)
 	     * Unhandle buffers need to be put back first
 	     * in out_queue.
 	     */
-	    erts_smp_mtx_lock(&dep->qlock);
-	    dep->qsize -= obufsize;
+	    erts_mtx_lock(&dep->qlock);
+	    erts_atomic_add_nob(&dep->qsize, -obufsize);
 	    obufsize = 0;
 	    oq.last->next = dep->out_queue.first;
 	    dep->out_queue.first = oq.first;
 	    if (!dep->out_queue.last)
 		dep->out_queue.last = oq.last;
-	    erts_smp_mtx_unlock(&dep->qlock);
+	    erts_mtx_unlock(&dep->qlock);
 	}
 
 	erts_schedule_dist_command(prt, NULL);
@@ -2366,6 +2549,369 @@ erts_dist_command(Port *prt, int reds_limit)
     goto done;
 }
 
+#if 0
+
+int
+dist_data_finalize(Process *c_p, int reds_limit)
+{
+    int reds = 5;
+    DistEntry *dep = ;
+    ErtsDistOutputQueue oq, foq;
+    ErtsDistOutputBuf *ob;
+    int preempt;
+
+
+    erts_mtx_lock(&dep->qlock);
+    flags = dep->flags;
+    oq.first = dep->out_queue.first;
+    oq.last = dep->out_queue.last;
+    dep->out_queue.first = NULL;
+    dep->out_queue.last = NULL;
+    erts_mtx_unlock(&dep->qlock);
+
+    if (!oq.first) {
+        ASSERT(!oq.last);
+        oq.first = dep->tmp_out_queue.first;
+        oq.last = dep->tmp_out_queue.last;
+    }
+    else {
+        ErtsDistOutputBuf *f, *l;
+        ASSERT(oq.last);
+        if (dep->tmp_out_queue.last) {
+            dep->tmp_out_queue.last->next = oq.first;
+            oq.first = dep->tmp_out_queue.first;
+        }
+    }
+
+    if (!oq.first) {
+        /* Nothing to do... */
+        ASSERT(!oq.last);
+        return reds;
+    }
+
+    foq.first = dep->finalized_out_queue.first;
+    foq.last = dep->finalized_out_queue.last;
+
+    preempt = 0;
+    ob = oq.first;
+    ASSERT(ob);
+
+    do {
+        ob->extp = erts_encode_ext_dist_header_finalize(ob->extp,
+                                                        dep->cache,
+                                                        flags);
+        if (!(flags & DFLAG_DIST_HDR_ATOM_CACHE))
+            *--ob->extp = PASS_THROUGH; /* Old node; 'pass through'
+                                           needed */
+        ASSERT(&ob->data[0] <= ob->extp && ob->extp < ob->ext_endp);
+        reds += ERTS_PORT_REDS_DIST_CMD_FINALIZE;
+        preempt = reds > reds_limit;
+        if (preempt)
+            break;
+        ob = ob->next;
+    } while (ob);
+    /*
+     * At least one buffer was finalized; if we got preempted,
+     * ob points to the last buffer that we finalized.
+     */
+    if (foq.last)
+        foq.last->next = oq.first;
+    else
+        foq.first = oq.first;
+    if (!preempt) {
+        /* All buffers finalized */
+        foq.last = oq.last;
+        oq.first = oq.last = NULL;
+    }
+    else {
+        /* Not all buffers finalized; split oq. */
+        foq.last = ob;
+        oq.first = ob->next;
+        if (oq.first)
+            ob->next = NULL;
+        else
+            oq.last = NULL;
+    }
+
+    dep->finalized_out_queue.first = foq.first;
+    dep->finalized_out_queue.last = foq.last;
+    dep->tmp_out_queue.first = oq.first;
+    dep->tmp_out_queue.last = oq.last;
+
+    return reds;
+}
+
+#endif
+
+BIF_RETTYPE
+dist_ctrl_get_data_notification_1(BIF_ALIST_1)
+{
+    DistEntry *dep = ERTS_PROC_GET_DIST_ENTRY(BIF_P);
+    erts_aint32_t qflgs;
+    erts_aint_t qsize;
+    Eterm receiver = NIL;
+
+    if (!dep)
+        BIF_ERROR(BIF_P, EXC_NOTSUP);
+
+    if (erts_dhandle_to_dist_entry(BIF_ARG_1) != dep)
+        BIF_ERROR(BIF_P, BADARG);
+
+    /*
+     * Caller is the only one that can consume from this queue
+     * and the only one that can set the req-info flag...
+     */
+
+    erts_de_rlock(dep);
+
+    ASSERT(dep->cid == BIF_P->common.id);
+
+    qflgs = erts_atomic32_read_acqb(&dep->qflgs);
+
+    if (!(qflgs & ERTS_DE_QFLG_REQ_INFO)) {
+        qsize = erts_atomic_read_acqb(&dep->qsize);
+        ASSERT(qsize >= 0);
+        if (qsize > 0)
+            receiver = BIF_P->common.id; /* Notify ourselves... */
+        else { /* Empty queue; set req-info flag... */
+            qflgs = erts_atomic32_read_bor_mb(&dep->qflgs,
+                                                  ERTS_DE_QFLG_REQ_INFO);
+            qsize = erts_atomic_read_acqb(&dep->qsize);
+            ASSERT(qsize >= 0);
+            if (qsize > 0) {
+                qflgs = erts_atomic32_read_band_mb(&dep->qflgs,
+                                                       ~ERTS_DE_QFLG_REQ_INFO);
+                if (qflgs & ERTS_DE_QFLG_REQ_INFO)
+                    receiver = BIF_P->common.id; /* Notify ourselves... */
+                /* else: someone else will notify us... */
+            }
+            /* else: still empty queue... */
+        }
+    }
+    /* else: Already requested... */
+
+    erts_de_runlock(dep);
+
+    if (is_internal_pid(receiver))
+        notify_dist_data(BIF_P, receiver);
+
+    BIF_RET(am_ok);
+}
+
+BIF_RETTYPE
+dist_ctrl_put_data_2(BIF_ALIST_2)
+{
+    DistEntry *dep;
+    ErlDrvSizeT size;
+    Eterm input_handler;
+
+    if (is_binary(BIF_ARG_2))
+        size = binary_size(BIF_ARG_2);
+    else if (is_nil(BIF_ARG_2))
+        size = 0;
+    else if (is_list(BIF_ARG_2))
+        BIF_TRAP2(dist_ctrl_put_data_trap,
+                  BIF_P, BIF_ARG_1, BIF_ARG_2);
+    else
+        BIF_ERROR(BIF_P, BADARG);
+
+    dep = erts_dhandle_to_dist_entry(BIF_ARG_1);
+    if (!dep)
+        BIF_ERROR(BIF_P, BADARG);
+
+    input_handler = (Eterm) erts_atomic_read_nob(&dep->input_handler);
+
+    if (input_handler != BIF_P->common.id)
+        BIF_ERROR(BIF_P, EXC_NOTSUP);
+
+    erts_atomic64_inc_nob(&dep->in);
+
+    if (size != 0) {
+        byte *data, *temp_alloc = NULL;
+
+        data = (byte *) erts_get_aligned_binary_bytes(BIF_ARG_2, &temp_alloc);
+        if (!data)
+            BIF_ERROR(BIF_P, BADARG);
+
+        erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+
+        (void) erts_net_message(NULL, dep, NULL, 0, data, size);
+        /*
+         * We ignore any decode failures. On fatal failures the
+         * connection will be taken down by killing the
+         * distribution channel controller...
+         */
+
+        erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+
+        BUMP_REDS(BIF_P, 5);
+
+        erts_free_aligned_binary_bytes(temp_alloc);
+
+    }
+
+    BIF_RET(am_ok);
+}
+
+BIF_RETTYPE
+dist_get_stat_1(BIF_ALIST_1)
+{
+    Sint64 read, write, pend;
+    Eterm res, *hp, **hpp;
+    Uint sz, *szp;
+    DistEntry *dep = erts_dhandle_to_dist_entry(BIF_ARG_1);
+
+    if (!dep)
+        BIF_ERROR(BIF_P, BADARG);
+
+    erts_de_rlock(dep);
+
+    read = (Sint64) erts_atomic64_read_nob(&dep->in);
+    write = (Sint64) erts_atomic64_read_nob(&dep->out);
+    pend = (Sint64) erts_atomic_read_nob(&dep->qsize);
+
+    erts_de_runlock(dep);
+
+    sz = 0;
+    szp = &sz;
+    hpp = NULL;
+
+    while (1) {
+        res = erts_bld_tuple(hpp, szp, 4,
+                             am_ok,
+                             erts_bld_sint64(hpp, szp, read),
+                             erts_bld_sint64(hpp, szp, write),
+                             pend ? am_true : am_false);
+        if (hpp)
+            break;
+        hp = HAlloc(BIF_P, sz);
+        hpp = &hp;
+        szp = NULL;
+    }
+
+    BIF_RET(res);
+}
+
+BIF_RETTYPE
+dist_ctrl_input_handler_2(BIF_ALIST_2)
+{
+    DistEntry *dep = ERTS_PROC_GET_DIST_ENTRY(BIF_P);
+
+    if (!dep)
+        BIF_ERROR(BIF_P, EXC_NOTSUP);
+
+    if (erts_dhandle_to_dist_entry(BIF_ARG_1) != dep)
+        BIF_ERROR(BIF_P, BADARG);
+
+    if (is_not_internal_pid(BIF_ARG_2))
+        BIF_ERROR(BIF_P, BADARG);
+
+    erts_atomic_set_nob(&dep->input_handler,
+                        (erts_aint_t) BIF_ARG_2);
+
+    BIF_RET(am_ok);
+}
+
+BIF_RETTYPE
+dist_ctrl_get_data_1(BIF_ALIST_1)
+{
+    DistEntry *dep = ERTS_PROC_GET_DIST_ENTRY(BIF_P);
+    const Sint initial_reds = ERTS_BIF_REDS_LEFT(BIF_P);
+    Sint reds = initial_reds;
+    ErtsDistOutputBuf *obuf;
+    Eterm *hp;
+    ProcBin *pb;
+    erts_aint_t qsize;
+
+    if (!dep)
+        BIF_ERROR(BIF_P, EXC_NOTSUP);
+
+    if (erts_dhandle_to_dist_entry(BIF_ARG_1) != dep)
+        BIF_ERROR(BIF_P, BADARG);
+
+    erts_de_rlock(dep);
+
+    if (dep->status & ERTS_DE_SFLG_EXITING)
+        goto return_none;
+
+    ASSERT(dep->cid == BIF_P->common.id);
+
+#if 0
+    if (dep->finalized_out_queue.first) {
+        obuf = dep->finalized_out_queue.first;
+        dep->finalized_out_queue.first = obuf->next;
+        if (!obuf->next)
+            dep->finalized_out_queue.last = NULL;
+    }
+    else
+#endif
+    {
+        if (!dep->tmp_out_queue.first) {
+            ASSERT(!dep->tmp_out_queue.last);
+            ASSERT(!dep->transcode_ctx);
+            qsize = erts_atomic_read_acqb(&dep->qsize);
+            if (qsize > 0) {
+                erts_mtx_lock(&dep->qlock);
+                dep->tmp_out_queue.first = dep->out_queue.first;
+                dep->tmp_out_queue.last = dep->out_queue.last;
+                dep->out_queue.first = NULL;
+                dep->out_queue.last = NULL;
+                erts_mtx_unlock(&dep->qlock);
+            }
+        }
+
+        if (!dep->tmp_out_queue.first) {
+            ASSERT(!dep->tmp_out_queue.last);
+        return_none:
+            erts_de_runlock(dep);
+            BIF_RET(am_none);
+        }
+
+        obuf = dep->tmp_out_queue.first;
+        reds = erts_encode_ext_dist_header_finalize(obuf, dep, dep->flags, reds);
+        if (reds < 0) {
+            erts_de_runlock(dep);
+            ERTS_BIF_YIELD1(bif_export[BIF_dist_ctrl_get_data_1],
+                            BIF_P, BIF_ARG_1);
+        }
+
+        dep->tmp_out_queue.first = obuf->next;
+        if (!obuf->next)
+            dep->tmp_out_queue.last = NULL;
+    }
+
+    erts_atomic64_inc_nob(&dep->out);
+
+    erts_de_runlock(dep);
+
+    hp =  HAlloc(BIF_P, PROC_BIN_SIZE);
+    pb = (ProcBin *) (char *) hp;
+    pb->thing_word = HEADER_PROC_BIN;
+    pb->size = obuf->ext_endp - obuf->extp;
+    pb->next = MSO(BIF_P).first;
+    MSO(BIF_P).first = (struct erl_off_heap_header*) pb;
+    pb->val = ErtsDistOutputBuf2Binary(obuf);
+    pb->bytes = (byte*) obuf->extp;
+    pb->flags = 0;
+
+    qsize = erts_atomic_add_read_nob(&dep->qsize, -size_obuf(obuf));
+    ASSERT(qsize >= 0);
+
+    if (qsize < erts_dist_buf_busy_limit/2
+        && (erts_atomic32_read_acqb(&dep->qflgs) & ERTS_DE_QFLG_BUSY)) {
+        ErtsProcList *resume_procs = NULL;
+        erts_mtx_lock(&dep->qlock);
+        resume_procs = get_suspended_on_de(dep, ERTS_DE_QFLG_BUSY);
+        erts_mtx_unlock(&dep->qlock);
+        if (resume_procs) {
+            int resumed = erts_resume_processes(resume_procs);
+            reds -= resumed*ERTS_PORT_REDS_DIST_CMD_RESUMED;
+        }
+    }
+
+    BIF_RET2(make_binary(pb), (initial_reds - reds));
+}
+
 void
 erts_dist_port_not_busy(Port *prt)
 {
@@ -2385,24 +2931,33 @@ erts_dist_port_not_busy(Port *prt)
     erts_schedule_dist_command(prt, NULL);
 }
 
+static void kill_connection(DistEntry *dep)
+{
+    ERTS_LC_ASSERT(erts_lc_is_de_rwlocked(dep));
+    ASSERT(dep->status == ERTS_DE_SFLG_CONNECTED);
+
+    dep->status |= ERTS_DE_SFLG_EXITING;
+    erts_mtx_lock(&dep->qlock);
+    ASSERT(!(erts_atomic32_read_nob(&dep->qflgs) & ERTS_DE_QFLG_EXIT));
+    erts_atomic32_read_bor_nob(&dep->qflgs, ERTS_DE_QFLG_EXIT);
+    erts_mtx_unlock(&dep->qlock);
+
+    if (is_internal_port(dep->cid))
+        erts_schedule_dist_command(NULL, dep);
+    else if (is_internal_pid(dep->cid))
+        schedule_kill_dist_ctrl_proc(dep->cid);
+}
+
 void
 erts_kill_dist_connection(DistEntry *dep, Uint32 connection_id)
 {
-    erts_smp_de_rwlock(dep);
-    if (is_internal_port(dep->cid)
-	&& connection_id == dep->connection_id
-	&& !(dep->status & ERTS_DE_SFLG_EXITING)) {
-
-	dep->status |= ERTS_DE_SFLG_EXITING;
+    erts_de_rwlock(dep);
+    if (connection_id == dep->connection_id
+        && dep->status == ERTS_DE_SFLG_CONNECTED) {
 
-	erts_smp_mtx_lock(&dep->qlock);
-	ASSERT(!(dep->qflgs & ERTS_DE_QFLG_EXIT));
-	dep->qflgs |= ERTS_DE_QFLG_EXIT;
-	erts_smp_mtx_unlock(&dep->qlock);
-
-	erts_schedule_dist_command(NULL, dep);
+        kill_connection(dep);
     }
-    erts_smp_de_rwunlock(dep);
+    erts_de_rwunlock(dep);
 }
 
 struct print_to_data {
@@ -2517,9 +3072,6 @@ info_dist_entry(fmtfn_t to, void *arg, DistEntry *dep, int visible, int connecte
   }
 
   erts_print(to, arg, "Name: %T", dep->sysname);
-#ifdef DEBUG
-  erts_print(to, arg, " (refc=%d)", erts_smp_refc_read(&dep->refc, 0));
-#endif
   erts_print(to, arg, "\n");
   if (!connected && is_nil(dep->cid)) {
     if (dep->nlinks) {
@@ -2563,6 +3115,10 @@ int distribution_info(fmtfn_t to, void *arg)	/* Called by break handler */
       info_dist_entry(to, arg, dep, 0, 1);
     }
 
+    for (dep = erts_pending_dist_entries; dep; dep = dep->next) {
+        info_dist_entry(to, arg, dep, 0, 0);
+    }
+
     for (dep = erts_not_connected_dist_entries; dep; dep = dep->next) {
         if (dep != erts_this_dist_entry) {
             info_dist_entry(to, arg, dep, 0, 0);
@@ -2585,7 +3141,6 @@ int distribution_info(fmtfn_t to, void *arg)	/* Called by break handler */
 	    monitor_node  -- turn on/off node monitoring
 
             node controller only:
-            dist_exit/3       -- send exit signals from remote to local process
             dist_link/2       -- link a remote process to a local
             dist_unlink/2     -- unlink a remote from a local
 ****************************************************************************/
@@ -2595,15 +3150,6 @@ int distribution_info(fmtfn_t to, void *arg)	/* Called by break handler */
 /**********************************************************************
  ** Set the node name of current node fail if node already is set.
  ** setnode(name@host, Creation)
- ** loads functions pointer to trap_functions from module erlang.
- **    erlang:dsend/2
- **    erlang:dlink/1
- **    erlang:dunlink/1
- **    erlang:dmonitor_node/3
- **    erlang:dgroup_leader/2
- **    erlang:dexit/2
- **  -- are these needed ?
- **    dexit/1
  ***********************************************************************/
 
 BIF_RETTYPE setnode_2(BIF_ALIST_2)
@@ -2627,44 +3173,51 @@ BIF_RETTYPE setnode_2(BIF_ALIST_2)
 	goto error;
 
     /* Check that all trap functions are defined !! */
-    if (dsend2_trap->addressv[0] == NULL ||
-	dsend3_trap->addressv[0] == NULL ||
-	/*	dsend_nosuspend_trap->address == NULL ||*/
-	dlink_trap->addressv[0] == NULL ||
-	dunlink_trap->addressv[0] == NULL ||
-	dmonitor_node_trap->addressv[0] == NULL ||
-	dgroup_leader_trap->addressv[0] == NULL ||
-	dmonitor_p_trap->addressv[0] == NULL ||
-	dexit_trap->addressv[0] == NULL) {
+    if (dmonitor_node_trap->addressv[0] == NULL ||
+	dmonitor_p_trap->addressv[0] == NULL) {
 	goto error;
     }
 
-    net_kernel = erts_whereis_process(BIF_P, ERTS_PROC_LOCK_MAIN,
-				      am_net_kernel, ERTS_PROC_LOCK_MAIN, 0);
-    if (!net_kernel)
+    net_kernel = erts_whereis_process(BIF_P,
+                                      ERTS_PROC_LOCK_MAIN,
+				      am_net_kernel,
+                                      ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_STATUS,
+                                      0);
+    if (!net_kernel || ERTS_PROC_GET_DIST_ENTRY(net_kernel))
 	goto error;
 
     /* By setting F_DISTRIBUTION on net_kernel,
-     * do_net_exist will be called when net_kernel is terminated !! */
+     * erts_do_net_exits will be called when net_kernel is terminated !! */
     net_kernel->flags |= F_DISTRIBUTION;
 
-    if (net_kernel != BIF_P)
-	erts_smp_proc_unlock(net_kernel, ERTS_PROC_LOCK_MAIN);
+    erts_proc_unlock(net_kernel,
+                     (ERTS_PROC_LOCK_STATUS
+                      | ((net_kernel != BIF_P)
+                         ? ERTS_PROC_LOCK_MAIN
+                         : 0)));
 
 #ifdef DEBUG
-    erts_smp_rwmtx_rlock(&erts_dist_table_rwmtx);
+    erts_rwmtx_rlock(&erts_dist_table_rwmtx);
     ASSERT(!erts_visible_dist_entries && !erts_hidden_dist_entries);
-    erts_smp_rwmtx_runlock(&erts_dist_table_rwmtx);
+    erts_rwmtx_runlock(&erts_dist_table_rwmtx);
 #endif
 
-    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-    erts_smp_thr_progress_block();
+    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    erts_thr_progress_block();
     inc_no_nodes();
     erts_set_this_node(BIF_ARG_1, (Uint32) creation);
     erts_is_alive = 1;
     send_nodes_mon_msgs(NULL, am_nodeup, BIF_ARG_1, am_visible, NIL);
-    erts_smp_thr_progress_unblock();
-    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    erts_thr_progress_unblock();
+    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+
+    /*
+     * Note erts_this_dist_entry is changed by erts_set_this_node(),
+     * so we *need* to use the new one after erts_set_this_node()
+     * is called.
+     */
+    erts_ref_dist_entry(erts_this_dist_entry);
+    ERTS_PROC_SET_DIST_ENTRY(net_kernel, erts_this_dist_entry);
 
     BIF_RET(am_true);
 
@@ -2695,18 +3248,20 @@ BIF_RETTYPE setnode_3(BIF_ALIST_3)
     Eterm ic, oc;
     Eterm *tp;
     DistEntry *dep = NULL;
+    ErtsProcLocks proc_unlock = 0;
+    Process *proc;
     Port *pp = NULL;
-
-    /* Prepare for success */
-    ERTS_BIF_PREP_RET(ret, am_true);
+    Eterm notify_proc;
+    erts_aint32_t qflgs;
 
     /*
      * Check and pick out arguments
      */
 
     if (!is_node_name_atom(BIF_ARG_1) ||
-	is_not_internal_port(BIF_ARG_2) ||
-	(erts_this_node->sysname == am_Noname)) {
+	!(is_internal_port(BIF_ARG_2)
+          || is_internal_pid(BIF_ARG_2))
+	|| (erts_this_node->sysname == am_Noname)) {
 	goto badarg;
     }
 
@@ -2725,21 +3280,25 @@ BIF_RETTYPE setnode_3(BIF_ALIST_3)
     if (!is_atom(ic) || !is_atom(oc))
 	goto badarg;
 
-    /* DFLAG_EXTENDED_REFERENCES is compulsory from R9 and forward */
-    if (!(DFLAG_EXTENDED_REFERENCES & flags)) {
+    if (~flags & DFLAG_DIST_MANDATORY) {
 	erts_dsprintf_buf_t *dsbufp = erts_create_logger_dsbuf();
 	erts_dsprintf(dsbufp, "%T", BIF_P->common.id);
 	if (BIF_P->common.u.alive.reg)
 	    erts_dsprintf(dsbufp, " (%T)", BIF_P->common.u.alive.reg->name);
 	erts_dsprintf(dsbufp,
 		      " attempted to enable connection to node %T "
-		      "which is not able to handle extended references.\n",
+		      "which does not support all mandatory capabilities.\n",
 		      BIF_ARG_1);
 	erts_send_error_to_logger(BIF_P->group_leader, dsbufp);
 	goto badarg;
     }
 
     /*
+     * ToDo: Should we not pass connection_id as well
+     *       to make sure it's the right connection we commit.
+     */
+
+    /*
      * Arguments seem to be in order.
      */
 
@@ -2750,77 +3309,165 @@ BIF_RETTYPE setnode_3(BIF_ALIST_3)
     else if (!dep)
 	goto system_limit; /* Should never happen!!! */
 
-    pp = erts_id2port_sflgs(BIF_ARG_2,
-			    BIF_P,
-			    ERTS_PROC_LOCK_MAIN,
-			    ERTS_PORT_SFLGS_INVALID_LOOKUP);
-    erts_smp_de_rwlock(dep);
+    if (is_internal_pid(BIF_ARG_2)) {
+        if (BIF_P->common.id == BIF_ARG_2) {
+            proc_unlock = 0;
+            proc = BIF_P;
+        }
+        else {
+            proc_unlock = ERTS_PROC_LOCK_MAIN;
+            proc = erts_pid2proc_not_running(BIF_P, ERTS_PROC_LOCK_MAIN,
+                                             BIF_ARG_2, proc_unlock);
+        }
+        erts_de_rwlock(dep);
 
-    if (!pp || (erts_atomic32_read_nob(&pp->state)
-		& ERTS_PORT_SFLG_EXITING))
-	goto badarg;
+        if (!proc)
+            goto badarg;
+        else if (proc == ERTS_PROC_LOCK_BUSY) {
+            proc_unlock = 0;
+            goto yield;
+        }
 
-    if ((pp->drv_ptr->flags & ERL_DRV_FLAG_SOFT_BUSY) == 0)
-	goto badarg;
+        erts_proc_lock(proc, ERTS_PROC_LOCK_STATUS);
+        proc_unlock |= ERTS_PROC_LOCK_STATUS;
 
-    if (dep->cid == BIF_ARG_2 && pp->dist_entry == dep)
-	goto done; /* Already set */
+        if (ERTS_PROC_GET_DIST_ENTRY(proc)) {
+            if (dep == ERTS_PROC_GET_DIST_ENTRY(proc)
+                && (proc->flags & F_DISTRIBUTION)
+                && dep->cid == BIF_ARG_2) {
+                ERTS_BIF_PREP_RET(ret, erts_make_dhandle(BIF_P, dep));
+                goto done;
+            }
+            goto badarg;
+        }
 
-    if (dep->status & ERTS_DE_SFLG_EXITING) {
-	/* Suspend on dist entry waiting for the exit to finish */
-	ErtsProcList *plp = erts_proclist_create(BIF_P);
-	plp->next = NULL;
-	erts_suspend(BIF_P, ERTS_PROC_LOCK_MAIN, NULL);
-	erts_smp_mtx_lock(&dep->qlock);
-	erts_proclist_store_last(&dep->suspended, plp);
-	erts_smp_mtx_unlock(&dep->qlock);
-	goto yield;
-    }
+        if (dep->status & ERTS_DE_SFLG_EXITING) {
+            /* Suspend on dist entry waiting for the exit to finish */
+            ErtsProcList *plp = erts_proclist_create(BIF_P);
+            plp->next = NULL;
+            erts_suspend(BIF_P, ERTS_PROC_LOCK_MAIN, NULL);
+            erts_mtx_lock(&dep->qlock);
+            erts_proclist_store_last(&dep->suspended, plp);
+            erts_mtx_unlock(&dep->qlock);
+            goto yield;
+        }
+        if (dep->status != ERTS_DE_SFLG_PENDING) {
+            if (dep->status == 0)
+                erts_set_dist_entry_pending(dep);
+            else
+                goto badarg;
+        }
 
-    ASSERT(!(dep->status & ERTS_DE_SFLG_EXITING));
+        if (is_not_nil(dep->cid))
+            goto badarg;
 
-    if (pp->dist_entry || is_not_nil(dep->cid))
-	goto badarg;
+        proc->flags |= F_DISTRIBUTION;
+        ERTS_PROC_SET_DIST_ENTRY(proc, dep);
 
-    erts_atomic32_read_bor_nob(&pp->state, ERTS_PORT_SFLG_DISTRIBUTION);
+        proc_unlock &= ~ERTS_PROC_LOCK_STATUS;
+        erts_proc_unlock(proc, ERTS_PROC_LOCK_STATUS);
+
+        dep->send = NULL; /* Only for distr ports... */
 
-    /*
-     * Dist-ports do not use the "busy port message queue" functionality, but
-     * instead use "busy dist entry" functionality.
-     */
-    {
-	ErlDrvSizeT disable = ERL_DRV_BUSY_MSGQ_DISABLED;
-	erl_drv_busy_msgq_limits(ERTS_Port2ErlDrvPort(pp), &disable, NULL);
     }
+    else {
 
-    pp->dist_entry = dep;
+        pp = erts_id2port_sflgs(BIF_ARG_2,
+                                BIF_P,
+                                ERTS_PROC_LOCK_MAIN,
+                                ERTS_PORT_SFLGS_INVALID_LOOKUP);
+        erts_de_rwlock(dep);
 
-    dep->version = version;
-    dep->creation = 0;
+        if (!pp || (erts_atomic32_read_nob(&pp->state)
+                    & ERTS_PORT_SFLG_EXITING))
+            goto badarg;
 
-    ASSERT(pp->drv_ptr->outputv || pp->drv_ptr->output);
+        if ((pp->drv_ptr->flags & ERL_DRV_FLAG_SOFT_BUSY) == 0)
+            goto badarg;
 
-#if 1
-    dep->send = (pp->drv_ptr->outputv
-		 ? dist_port_commandv
-		 : dist_port_command);
-#else
-    dep->send = dist_port_command;
-#endif
-    ASSERT(dep->send);
+        if (dep->cid == BIF_ARG_2 && pp->dist_entry == dep) {
+            ERTS_BIF_PREP_RET(ret, erts_make_dhandle(BIF_P, dep));
+            goto done; /* Already set */
+        }
+
+        if (dep->status & ERTS_DE_SFLG_EXITING) {
+            /* Suspend on dist entry waiting for the exit to finish */
+            ErtsProcList *plp = erts_proclist_create(BIF_P);
+            plp->next = NULL;
+            erts_suspend(BIF_P, ERTS_PROC_LOCK_MAIN, NULL);
+            erts_mtx_lock(&dep->qlock);
+            erts_proclist_store_last(&dep->suspended, plp);
+            erts_mtx_unlock(&dep->qlock);
+            goto yield;
+        }
+        if (dep->status != ERTS_DE_SFLG_PENDING) {
+            if (dep->status == 0)
+                erts_set_dist_entry_pending(dep);
+            else
+                goto badarg;
+        }
+
+        if (pp->dist_entry || is_not_nil(dep->cid))
+            goto badarg;
+
+        erts_atomic32_read_bor_nob(&pp->state, ERTS_PORT_SFLG_DISTRIBUTION);
+
+        pp->dist_entry = dep;
+
+        ASSERT(pp->drv_ptr->outputv || pp->drv_ptr->output);
+
+        dep->send = (pp->drv_ptr->outputv
+                     ? dist_port_commandv
+                     : dist_port_command);
+        ASSERT(dep->send);
+
+        /*
+         * Dist-ports do not use the "busy port message queue" functionality, but
+         * instead use "busy dist entry" functionality.
+         */
+        {
+            ErlDrvSizeT disable = ERL_DRV_BUSY_MSGQ_DISABLED;
+            erl_drv_busy_msgq_limits(ERTS_Port2ErlDrvPort(pp), &disable, NULL);
+        }
+
+    }
+
+    dep->version = version;
+    dep->creation = 0;
 
 #ifdef DEBUG
-    erts_smp_mtx_lock(&dep->qlock);
-    ASSERT(dep->qsize == 0);
-    erts_smp_mtx_unlock(&dep->qlock);
+    ASSERT(erts_atomic_read_nob(&dep->qsize) == 0 
+           || (dep->status & ERTS_DE_SFLG_PENDING));
 #endif
 
-    erts_set_dist_entry_connected(dep, BIF_ARG_2, flags);
-
     if (flags & DFLAG_DIST_HDR_ATOM_CACHE)
 	create_cache(dep);
 
-    erts_smp_de_rwunlock(dep);
+    erts_set_dist_entry_connected(dep, BIF_ARG_2, flags);
+
+    notify_proc = NIL;
+    if (erts_atomic_read_nob(&dep->qsize)) {
+        if (is_internal_port(dep->cid)) {
+            erts_schedule_dist_command(NULL, dep);
+        }
+        else {
+            qflgs = erts_atomic32_read_nob(&dep->qflgs);
+            if (qflgs & ERTS_DE_QFLG_REQ_INFO) {
+                qflgs = erts_atomic32_read_band_mb(&dep->qflgs,
+                                                   ~ERTS_DE_QFLG_REQ_INFO);
+                if (qflgs & ERTS_DE_QFLG_REQ_INFO) {
+                    notify_proc = dep->cid;
+                    ASSERT(is_internal_pid(notify_proc));
+                }
+            }
+        }
+    }
+    erts_de_rwunlock(dep);
+    if (is_internal_pid(notify_proc))
+        notify_dist_data(BIF_P, notify_proc);
+
+    ERTS_BIF_PREP_RET(ret, erts_make_dhandle(BIF_P, dep));
+
     dep = NULL; /* inc of refc transferred to port (dist_entry field) */
 
     inc_no_nodes();
@@ -2833,13 +3480,16 @@ BIF_RETTYPE setnode_3(BIF_ALIST_3)
  done:
 
     if (dep && dep != erts_this_dist_entry) {
-	erts_smp_de_rwunlock(dep);
+	erts_de_rwunlock(dep);
 	erts_deref_dist_entry(dep);
     }
 
     if (pp)
 	erts_port_release(pp);
 
+    if (proc_unlock)
+        erts_proc_unlock(proc, proc_unlock);
+
     return ret;
 
  yield:
@@ -2856,83 +3506,168 @@ BIF_RETTYPE setnode_3(BIF_ALIST_3)
     goto done;
 }
 
+BIF_RETTYPE erts_internal_new_connection_1(BIF_ALIST_1)
+{
+    DistEntry* dep;
+    Uint32 conn_id;
+    Eterm* hp;
+    Eterm dhandle;
 
-/**********************************************************************/
-/* dist_exit(Local, Term, Remote) -> Bool */
+    if (is_not_atom(BIF_ARG_1)) {
+	BIF_ERROR(BIF_P, BADARG);
+    }
+    dep = erts_find_or_insert_dist_entry(BIF_ARG_1);
+
+    if (dep == erts_this_dist_entry) {
+        erts_deref_dist_entry(dep);
+        BIF_ERROR(BIF_P, BADARG);
+    }
 
-BIF_RETTYPE dist_exit_3(BIF_ALIST_3)
+    erts_de_rwlock(dep);
+
+    if (ERTS_DE_IS_CONNECTED(dep) || dep->status & ERTS_DE_SFLG_PENDING)
+	conn_id = dep->connection_id;
+    else if (dep->status == 0) {
+        erts_set_dist_entry_pending(dep);
+	conn_id = dep->connection_id;
+    }
+    else {
+        ASSERT(dep->status & ERTS_DE_SFLG_EXITING);
+        conn_id = (dep->connection_id + 1) & ERTS_DIST_CON_ID_MASK;
+    }
+    erts_de_rwunlock(dep);
+    hp = HAlloc(BIF_P, 3 + ERTS_MAGIC_REF_THING_SIZE);
+    dhandle = erts_build_dhandle(&hp, &BIF_P->off_heap, dep);
+    erts_deref_dist_entry(dep);
+    BIF_RET(TUPLE2(hp, make_small(conn_id), dhandle));
+}
+
+static Sint abort_connection(DistEntry* dep, Uint32 conn_id)
 {
-    Eterm local;
-    Eterm remote;
-    DistEntry *rdep;
+    erts_de_rwlock(dep);
 
-    local = BIF_ARG_1;
-    remote = BIF_ARG_3;
+    if (dep->connection_id != conn_id)
+        ;
+    else if (dep->status == ERTS_DE_SFLG_CONNECTED) {
+        kill_connection(dep);
+    }
+    else if (dep->status == ERTS_DE_SFLG_PENDING) {
+        NetExitsContext nec = {dep};
+        ErtsLink *nlinks;
+        ErtsLink *node_links;
+        ErtsMonitor *monitors;
+        ErtsAtomCache *cache;
+        ErtsDistOutputBuf *obuf;
+        ErtsProcList *resume_procs;
+        Sint reds = 0;
+
+	ASSERT(is_nil(dep->cid));
+
+	erts_de_links_lock(dep);
+	monitors	= dep->monitors;
+	nlinks		= dep->nlinks;
+	node_links	= dep->node_links;
+	dep->monitors	= NULL;
+	dep->nlinks	= NULL;
+	dep->node_links	= NULL;
+	erts_de_links_unlock(dep);
+
+	cache = dep->cache;
+	dep->cache = NULL;
+	erts_mtx_lock(&dep->qlock);
+        obuf = dep->out_queue.first;
+        dep->out_queue.first = NULL;
+        dep->out_queue.last = NULL;
+        ASSERT(!dep->tmp_out_queue.first);
+        ASSERT(!dep->finalized_out_queue.first);
+        resume_procs = get_suspended_on_de(dep, ERTS_DE_QFLGS_ALL);
+	erts_mtx_unlock(&dep->qlock);
+	erts_atomic_set_nob(&dep->dist_cmd_scheduled, 0);
+	dep->send = NULL;
+
+        erts_set_dist_entry_not_connected(dep);
+
+	erts_de_rwunlock(dep);
+
+	erts_sweep_monitors(monitors, &doit_monitor_net_exits, &nec);
+	erts_sweep_links(nlinks, &doit_link_net_exits, &nec);
+	erts_sweep_links(node_links, &doit_node_link_net_exits, &nec);
+
+        if (resume_procs) {
+            int resumed = erts_resume_processes(resume_procs);
+            reds += resumed*ERTS_PORT_REDS_DIST_CMD_RESUMED;
+        }
 
-    /* Check that remote is a remote process */
-    if (is_not_external_pid(remote))
-	goto error;
+	delete_cache(cache);
+	free_de_out_queues(dep, obuf);
+        return reds;
+    }
+    erts_de_rwunlock(dep);
+    return 0;
+}
 
-    rdep = external_dist_entry(remote);
-    
-    if(rdep == erts_this_dist_entry)
-	goto error;
+BIF_RETTYPE erts_internal_abort_connection_2(BIF_ALIST_2)
+{
+    DistEntry* dep;
+    Eterm* tp;
 
-    /* Check that local is local */
-    if (is_internal_pid(local)) {
-	Process *lp;
-	ErtsProcLocks lp_locks;
-	if (BIF_P->common.id == local) {
-	    lp_locks = ERTS_PROC_LOCKS_ALL;
-	    lp = BIF_P;
-	    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCKS_ALL_MINOR);
-	}
-	else {
-	    lp_locks = ERTS_PROC_LOCKS_XSIG_SEND;
-	    lp = erts_pid2proc(BIF_P, ERTS_PROC_LOCK_MAIN,
-			       local, lp_locks);
-	    if (!lp) {
-		BIF_RET(am_true); /* ignore */
-	    }
-	}
-	
-	(void) erts_send_exit_signal(BIF_P,
-				     remote,
-				     lp,
-				     &lp_locks,
-				     BIF_ARG_2,
-				     NIL,
-				     NULL,
-				     0);
-#ifdef ERTS_SMP
-	if (lp == BIF_P)
-	    lp_locks &= ~ERTS_PROC_LOCK_MAIN;
-#endif
-	erts_smp_proc_unlock(lp, lp_locks);
-	if (lp == BIF_P) {
-	    erts_aint32_t state = erts_smp_atomic32_read_acqb(&BIF_P->state);
-	    /*
-	     * We may have exited current process and may have to take action.
-	     */
-	    if (state & (ERTS_PSFLG_EXITING|ERTS_PSFLG_PENDING_EXIT)) {
-#ifdef ERTS_SMP
-		if (state & ERTS_PSFLG_PENDING_EXIT)
-		    erts_handle_pending_exit(BIF_P, ERTS_PROC_LOCK_MAIN);
-#endif
-		ERTS_BIF_EXITED(BIF_P);
-	    }
-	}
+    if (is_not_atom(BIF_ARG_1) || is_not_tuple_arity(BIF_ARG_2, 2)) {
+	BIF_ERROR(BIF_P, BADARG);
     }
-    else if (is_external_pid(local)
-	     && external_dist_entry(local) == erts_this_dist_entry) {
-	BIF_RET(am_true); /* ignore */
+    tp = tuple_val(BIF_ARG_2);
+    dep = erts_dhandle_to_dist_entry(tp[2]);
+    if (is_not_small(tp[1]) || dep != erts_find_dist_entry(BIF_ARG_1)
+        || dep == erts_this_dist_entry) {
+        BIF_ERROR(BIF_P, BADARG);
+    }
+
+    if (dep) {
+        Sint reds = abort_connection(dep, unsigned_val(tp[1]));
+        BUMP_REDS(BIF_P, reds);
     }
-    else
-	goto error;
     BIF_RET(am_true);
+}
 
- error:
-    BIF_ERROR(BIF_P, BADARG);
+int erts_auto_connect(DistEntry* dep, Process *proc, ErtsProcLocks proc_locks)
+{
+    erts_de_rwlock(dep);
+    if (dep->status != 0) {
+        erts_de_rwunlock(dep);
+    }
+    else {
+        Process* net_kernel;
+        ErtsProcLocks nk_locks = ERTS_PROC_LOCK_MSGQ;
+        Eterm *hp;
+        ErlOffHeap *ohp;
+        ErtsMessage *mp;
+        Eterm msg, dhandle;
+        Uint32 conn_id;
+
+        erts_set_dist_entry_pending(dep);
+        conn_id = dep->connection_id;
+        erts_de_rwunlock(dep);
+
+        net_kernel = erts_whereis_process(proc, proc_locks,
+                                          am_net_kernel, nk_locks, 0);
+        if (!net_kernel) {
+            abort_connection(dep, conn_id);
+            return 0;
+        }
+
+        /*
+         * Send {auto_connect, Node, ConnId, DHandle} to net_kernel
+         */
+        mp = erts_alloc_message_heap(net_kernel, &nk_locks,
+                                     5 + ERTS_MAGIC_REF_THING_SIZE,
+                                     &hp, &ohp);
+        dhandle = erts_build_dhandle(&hp, ohp, dep);
+        msg = TUPLE4(hp, am_auto_connect, dep->sysname, make_small(conn_id),
+                     dhandle);
+        erts_queue_message(net_kernel, nk_locks, mp, msg, proc->common.id);
+        erts_proc_unlock(net_kernel, nk_locks);
+    }
+
+    return 1;
 }
 
 /**********************************************************************/
@@ -3004,13 +3739,15 @@ BIF_RETTYPE nodes_1(BIF_ALIST_1)
 
     length = 0;
 
-    erts_smp_rwmtx_rlock(&erts_dist_table_rwmtx);
+    erts_rwmtx_rlock(&erts_dist_table_rwmtx);
 
     ASSERT(erts_no_of_not_connected_dist_entries > 0);
     ASSERT(erts_no_of_hidden_dist_entries >= 0);
+    ASSERT(erts_no_of_pending_dist_entries >= 0);
     ASSERT(erts_no_of_visible_dist_entries >= 0);
     if(not_connected)
-      length += (erts_no_of_not_connected_dist_entries - 1);
+      length += ((erts_no_of_not_connected_dist_entries - 1)
+                 + erts_no_of_pending_dist_entries);
     if(hidden)
       length += erts_no_of_hidden_dist_entries;
     if(visible)
@@ -3021,7 +3758,7 @@ BIF_RETTYPE nodes_1(BIF_ALIST_1)
     result = NIL;
 
     if (length == 0) {
-	erts_smp_rwmtx_runlock(&erts_dist_table_rwmtx);
+	erts_rwmtx_runlock(&erts_dist_table_rwmtx);
 	goto done;
     }
 
@@ -3030,13 +3767,18 @@ BIF_RETTYPE nodes_1(BIF_ALIST_1)
 #ifdef DEBUG
     endp = hp + length*2;
 #endif
-    if(not_connected)
+    if(not_connected) {
       for(dep = erts_not_connected_dist_entries; dep; dep = dep->next) {
           if (dep != erts_this_dist_entry) {
             result = CONS(hp, dep->sysname, result);
             hp += 2;
           }
+        }
+      for(dep = erts_pending_dist_entries; dep; dep = dep->next) {
+          result = CONS(hp, dep->sysname, result);
+          hp += 2;
       }
+    }
     if(hidden)
       for(dep = erts_hidden_dist_entries; dep; dep = dep->next) {
 	result = CONS(hp, dep->sysname, result);
@@ -3052,7 +3794,7 @@ BIF_RETTYPE nodes_1(BIF_ALIST_1)
 	hp += 2;
     }
     ASSERT(endp == hp);
-    erts_smp_rwmtx_runlock(&erts_dist_table_rwmtx);
+    erts_rwmtx_runlock(&erts_dist_table_rwmtx);
 
 done:
     UnUseTmpHeap(2,BIF_P);
@@ -3081,11 +3823,17 @@ monitor_node(Process* p, Eterm Node, Eterm Bool, Eterm Options)
     DistEntry *dep;
     ErtsLink *lnk;
     Eterm l;
+    int async_connect = 1;
 
     for (l = Options; l != NIL && is_list(l); l = CDR(list_val(l))) {
 	Eterm t = CAR(list_val(l));
-	/* allow_passive_connect the only available option right now */
-	if (t != am_allow_passive_connect) {
+	if (t == am_allow_passive_connect) {
+	    /*
+	     * Handle this horrible feature by falling back on old synchronous
+	     * auto-connect (if needed)
+	     */
+	    async_connect = 0;
+	} else {
 	    BIF_ERROR(p, BADARG);
 	}
     }
@@ -3099,54 +3847,93 @@ monitor_node(Process* p, Eterm Node, Eterm Bool, Eterm Options)
 	 && (Node != erts_this_node->sysname))) {
 	BIF_ERROR(p, BADARG);
     }
-    dep = erts_sysname_to_connected_dist_entry(Node);
-    if (!dep) {
-    do_trap:
-	BIF_TRAP3(dmonitor_node_trap, p, Node, Bool, Options);
-    }
-    if (dep == erts_this_dist_entry)
-	goto done;
-
-    erts_smp_proc_lock(p, ERTS_PROC_LOCK_LINK);
-    erts_smp_de_rlock(dep);
-    if (ERTS_DE_IS_NOT_CONNECTED(dep)) {
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_LINK);
-	erts_smp_de_runlock(dep);
-	goto do_trap;
-    }
-    erts_smp_de_links_lock(dep);
-    erts_smp_de_runlock(dep);
 
     if (Bool == am_true) {
-	ASSERT(dep->cid != NIL);
-	lnk = erts_add_or_lookup_link(&(dep->node_links), LINK_NODE, 
-				      p->common.id);
-	++ERTS_LINK_REFC(lnk);
-	lnk = erts_add_or_lookup_link(&ERTS_P_LINKS(p), LINK_NODE, Node);
-	++ERTS_LINK_REFC(lnk);
-    }
-    else  {
-	lnk = erts_lookup_link(dep->node_links, p->common.id);
-	if (lnk != NULL) {
-	    if ((--ERTS_LINK_REFC(lnk)) == 0) {
-		erts_destroy_link(erts_remove_link(&(dep->node_links), 
-						   p->common.id));
-	    }
-	}
-	lnk = erts_lookup_link(ERTS_P_LINKS(p), Node);
-	if (lnk != NULL) {
-	    if ((--ERTS_LINK_REFC(lnk)) == 0) {
-		erts_destroy_link(erts_remove_link(&ERTS_P_LINKS(p),
-						   Node));
+        ErtsDSigData dsd;
+        dsd.node = Node;
+        dep = erts_find_or_insert_dist_entry(Node);
+        if (dep == erts_this_dist_entry)
+            goto done;
+
+        erts_proc_lock(p, ERTS_PROC_LOCK_LINK);
+
+        switch (erts_dsig_prepare(&dsd, dep, p,
+                                  (ERTS_PROC_LOCK_MAIN | ERTS_PROC_LOCK_LINK),
+                                  ERTS_DSP_RLOCK, 0, async_connect)) {
+        case ERTS_DSIG_PREP_NOT_ALIVE:
+	case ERTS_DSIG_PREP_NOT_CONNECTED:
+	    /* Trap to either send 'nodedown' or do passive connection attempt */
+	trap:
+            erts_proc_unlock(p, ERTS_PROC_LOCK_LINK);
+	    erts_deref_dist_entry(dep);
+            BIF_TRAP3(dmonitor_node_trap, p, Node, Bool, Options);
+	case ERTS_DSIG_PREP_PENDING:
+	    if (!async_connect) {
+		/*
+		 * Pending connection may fail, so we must trap
+		 * to ensure passive connection attempt
+		 */
+		erts_de_runlock(dep);
+		goto trap;
 	    }
-	}
+	    /*fall through*/
+        case ERTS_DSIG_PREP_CONNECTED:
+            erts_de_links_lock(dep);
+            erts_de_runlock(dep);
+            lnk = erts_add_or_lookup_link(&(dep->node_links), LINK_NODE,
+                                          p->common.id);
+            ++ERTS_LINK_REFC(lnk);
+            lnk = erts_add_or_lookup_link(&ERTS_P_LINKS(p), LINK_NODE, Node);
+            ++ERTS_LINK_REFC(lnk);
+            erts_de_links_unlock(dep);
+            break;
+        default:
+            ERTS_ASSERT(! "Invalid dsig prepare result");
+        }
+        erts_deref_dist_entry(dep);
+    }
+    else { /* Bool == false */
+        dep = erts_sysname_to_connected_dist_entry(Node);
+        if (!dep) {
+	    /*
+	     * Before OTP-21 this case triggered auto-connect
+	     * and a 'nodedown' message if that failed.
+	     * Now it's a simple no-op which feels more reasonable.
+	     */
+            BIF_RET(am_true);
+        }
+        if (dep == erts_this_dist_entry)
+            goto done;
+
+        erts_proc_lock(p, ERTS_PROC_LOCK_LINK);
+        erts_de_rlock(dep);
+        if (!(dep->status & (ERTS_DE_SFLG_PENDING | ERTS_DE_SFLG_CONNECTED))) {
+            erts_proc_unlock(p, ERTS_PROC_LOCK_LINK);
+            erts_de_runlock(dep);
+            goto done;
+        }
+        erts_de_links_lock(dep);
+        erts_de_runlock(dep);
+        lnk = erts_lookup_link(dep->node_links, p->common.id);
+        if (lnk != NULL) {
+            if ((--ERTS_LINK_REFC(lnk)) == 0) {
+                erts_destroy_link(erts_remove_link(&(dep->node_links),
+                                                   p->common.id));
+            }
+        }
+        lnk = erts_lookup_link(ERTS_P_LINKS(p), Node);
+        if (lnk != NULL) {
+            if ((--ERTS_LINK_REFC(lnk)) == 0) {
+                erts_destroy_link(erts_remove_link(&ERTS_P_LINKS(p),
+                                                   Node));
+            }
+        }
+        erts_de_links_unlock(dep);
     }
 
-    erts_smp_de_links_unlock(dep);
-    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_LINK);
+    erts_proc_unlock(p, ERTS_PROC_LOCK_LINK);
 
  done:
-    erts_deref_dist_entry(dep);
     BIF_RET(am_true);
 }
 
@@ -3175,9 +3962,9 @@ BIF_RETTYPE net_kernel_dflag_unicode_io_1(BIF_ALIST_1)
     if (de == erts_this_dist_entry) {
 	BIF_RET(am_true);
     }
-    erts_smp_de_rlock(de);
+    erts_de_rlock(de);
     f = de->flags;
-    erts_smp_de_runlock(de);
+    erts_de_runlock(de);
     BIF_RET(((f & DFLAG_UNICODE_IO) ? am_true : am_false));
 }
     
@@ -3207,7 +3994,7 @@ struct ErtsNodesMonitor_ {
     Uint16 no;
 };
 
-static erts_smp_mtx_t nodes_monitors_mtx;
+static erts_mtx_t nodes_monitors_mtx;
 static ErtsNodesMonitor *nodes_monitors;
 static ErtsNodesMonitor *nodes_monitors_end;
 
@@ -3225,7 +4012,7 @@ static ErtsNodesMonitor *nodes_monitors_end;
 static void
 init_nodes_monitors(void)
 {
-    erts_smp_mtx_init(&nodes_monitors_mtx, "nodes_monitors", NIL,
+    erts_mtx_init(&nodes_monitors_mtx, "nodes_monitors", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_DISTRIBUTION);
     nodes_monitors = NULL;
     nodes_monitors_end = NULL;
@@ -3351,10 +4138,10 @@ send_nodes_mon_msgs(Process *c_p, Eterm what, Eterm node, Eterm type, Eterm reas
     }
 #endif
 
-    ERTS_SMP_LC_ASSERT(!c_p
+    ERTS_LC_ASSERT(!c_p
 		       || (erts_proc_lc_my_proc_locks(c_p)
 			   == ERTS_PROC_LOCK_MAIN));
-    erts_smp_mtx_lock(&nodes_monitors_mtx);
+    erts_mtx_lock(&nodes_monitors_mtx);
 
     for (nmp = nodes_monitors; nmp; nmp = nmp->next) {
 	int i;
@@ -3387,7 +4174,7 @@ send_nodes_mon_msgs(Process *c_p, Eterm what, Eterm node, Eterm type, Eterm reas
 	    if (rp) {
 		if (rp == c_p)
 		    rp_locks &= ~ERTS_PROC_LOCK_MAIN;
-		erts_smp_proc_unlock(rp, rp_locks);
+		erts_proc_unlock(rp, rp_locks);
 	    }
 
 	    rp = nmp->proc;
@@ -3414,10 +4201,10 @@ send_nodes_mon_msgs(Process *c_p, Eterm what, Eterm node, Eterm type, Eterm reas
     if (rp) {
 	if (rp == c_p)
 	    rp_locks &= ~ERTS_PROC_LOCK_MAIN;
-	erts_smp_proc_unlock(rp, rp_locks);
+	erts_proc_unlock(rp, rp_locks);
     }
 
-    erts_smp_mtx_unlock(&nodes_monitors_mtx);
+    erts_mtx_unlock(&nodes_monitors_mtx);
 }
 
 static Eterm
@@ -3427,8 +4214,8 @@ insert_nodes_monitor(Process *c_p, Uint32 opts)
     Eterm res = am_false;
     ErtsNodesMonitor *xnmp, *nmp;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_mtx_is_locked(&nodes_monitors_mtx));
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) & ERTS_PROC_LOCK_MAIN);
+    ERTS_LC_ASSERT(erts_lc_mtx_is_locked(&nodes_monitors_mtx));
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) & ERTS_PROC_LOCK_MAIN);
 
     xnmp = c_p->nodes_monitors;
     if (xnmp) {
@@ -3512,8 +4299,8 @@ remove_nodes_monitors(Process *c_p, Uint32 opts, int all)
     Eterm res = am_false;
     ErtsNodesMonitor *nmp;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_mtx_is_locked(&nodes_monitors_mtx));
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) & ERTS_PROC_LOCK_MAIN);
+    ERTS_LC_ASSERT(erts_lc_mtx_is_locked(&nodes_monitors_mtx));
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) & ERTS_PROC_LOCK_MAIN);
 
     nmp = c_p->nodes_monitors;
     ASSERT(!nmp || !nmp->prev || nmp->prev->proc != c_p);
@@ -3555,23 +4342,23 @@ remove_nodes_monitors(Process *c_p, Uint32 opts, int all)
 void
 erts_delete_nodes_monitors(Process *c_p, ErtsProcLocks locks)
 {
-#if defined(ERTS_ENABLE_LOCK_CHECK) && defined(ERTS_SMP)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     if (c_p) {
 	ErtsProcLocks might_unlock = locks & ~ERTS_PROC_LOCK_MAIN;
 	if (might_unlock)
 	    erts_proc_lc_might_unlock(c_p, might_unlock);
     }
 #endif
-    if (erts_smp_mtx_trylock(&nodes_monitors_mtx) == EBUSY) {
+    if (erts_mtx_trylock(&nodes_monitors_mtx) == EBUSY) {
 	ErtsProcLocks unlock_locks = locks & ~ERTS_PROC_LOCK_MAIN;
 	if (c_p && unlock_locks)
-	    erts_smp_proc_unlock(c_p, unlock_locks);
-	erts_smp_mtx_lock(&nodes_monitors_mtx);
+	    erts_proc_unlock(c_p, unlock_locks);
+	erts_mtx_lock(&nodes_monitors_mtx);
 	if (c_p && unlock_locks)
-	    erts_smp_proc_lock(c_p, unlock_locks);
+	    erts_proc_lock(c_p, unlock_locks);
     }
     remove_nodes_monitors(c_p, 0, 1);
-    erts_smp_mtx_unlock(&nodes_monitors_mtx);
+    erts_mtx_unlock(&nodes_monitors_mtx);
 }
 
 Eterm
@@ -3582,7 +4369,7 @@ erts_monitor_nodes(Process *c_p, Eterm on, Eterm olist)
     Uint16 opts = (Uint16) 0;
 
     ASSERT(c_p);
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == ERTS_PROC_LOCK_MAIN);
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == ERTS_PROC_LOCK_MAIN);
 
     if (on != am_true && on != am_false)
 	return THE_NON_VALUE;
@@ -3638,14 +4425,14 @@ erts_monitor_nodes(Process *c_p, Eterm on, Eterm olist)
 	    return THE_NON_VALUE;
     }
 
-    erts_smp_mtx_lock(&nodes_monitors_mtx);
+    erts_mtx_lock(&nodes_monitors_mtx);
 
     if (on == am_true)
 	res = insert_nodes_monitor(c_p, opts);
     else
 	res = remove_nodes_monitors(c_p, opts, 0);
 
-    erts_smp_mtx_unlock(&nodes_monitors_mtx);
+    erts_mtx_unlock(&nodes_monitors_mtx);
 
     return res;
 }
@@ -3668,8 +4455,8 @@ erts_processes_monitoring_nodes(Process *c_p)
 #endif
 
     ASSERT(c_p);
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == ERTS_PROC_LOCK_MAIN);
-    erts_smp_mtx_lock(&nodes_monitors_mtx);
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == ERTS_PROC_LOCK_MAIN);
+    erts_mtx_lock(&nodes_monitors_mtx);
 
     sz = 0;
     szp = &sz;
@@ -3718,7 +4505,7 @@ erts_processes_monitoring_nodes(Process *c_p)
 
     ASSERT(hp == hend);
 
-    erts_smp_mtx_unlock(&nodes_monitors_mtx);
+    erts_mtx_unlock(&nodes_monitors_mtx);
 
     return res;
 }
diff --git a/erts/emulator/beam/dist.h b/erts/emulator/beam/dist.h
index 3e17645997..ea4697815f 100644
--- a/erts/emulator/beam/dist.h
+++ b/erts/emulator/beam/dist.h
@@ -44,6 +44,21 @@
 #define DFLAG_UTF8_ATOMS          0x10000
 #define DFLAG_MAP_TAG             0x20000
 #define DFLAG_BIG_CREATION        0x40000
+#define DFLAG_SEND_SENDER         0x80000
+#define DFLAG_NO_MAGIC            0x100000
+
+/* Mandatory flags for distribution (sync with dist_util.erl) */
+#define DFLAG_DIST_MANDATORY (DFLAG_EXTENDED_REFERENCES         \
+                              | DFLAG_EXTENDED_PIDS_PORTS       \
+			      | DFLAG_UTF8_ATOMS                \
+			      | DFLAG_NEW_FUN_TAGS)
+
+/* Additional optimistic flags when encoding toward pending connection */
+#define DFLAG_DIST_HOPEFULLY (DFLAG_NO_MAGIC                    \
+                              | DFLAG_EXPORT_PTR_TAG            \
+                              | DFLAG_BIT_BINARIES              \
+                              | DFLAG_DIST_MONITOR              \
+                              | DFLAG_DIST_MONITOR_NAME)
 
 /* All flags that should be enabled when term_to_binary/1 is used. */
 #define TERM_TO_BINARY_DFLAGS (DFLAG_EXTENDED_REFERENCES	\
@@ -74,33 +89,30 @@
 #define DOP_DEMONITOR_P		20
 #define DOP_MONITOR_P_EXIT	21
 
+#define DOP_SEND_SENDER         22
+#define DOP_SEND_SENDER_TT      23
+
 /* distribution trap functions */
-extern Export* dsend2_trap;
-extern Export* dsend3_trap;
-extern Export* dlink_trap;
-extern Export* dunlink_trap;
 extern Export* dmonitor_node_trap;
-extern Export* dgroup_leader_trap;
-extern Export* dexit_trap;
 extern Export* dmonitor_p_trap;
 
 typedef enum {
     ERTS_DSP_NO_LOCK,
-    ERTS_DSP_RLOCK,
-    ERTS_DSP_RWLOCK
+    ERTS_DSP_RLOCK
 } ErtsDSigPrepLock;
 
 
 typedef struct {
     Process *proc;
     DistEntry *dep;
+    Eterm node;   /* used if dep == NULL */
     Eterm cid;
     Eterm connection_id;
     int no_suspend;
 } ErtsDSigData;
 
 #define ERTS_DE_IS_NOT_CONNECTED(DEP) \
-  (ERTS_SMP_LC_ASSERT(erts_lc_rwmtx_is_rlocked(&(DEP)->rwmtx) \
+  (ERTS_LC_ASSERT(erts_lc_rwmtx_is_rlocked(&(DEP)->rwmtx) \
 		      || erts_lc_rwmtx_is_rwlocked(&(DEP)->rwmtx)), \
    (is_nil((DEP)->cid) || ((DEP)->status & ERTS_DE_SFLG_EXITING)))
 
@@ -113,14 +125,10 @@ extern int erts_is_alive;
 
 /*
  * erts_dsig_prepare() prepares a send of a distributed signal.
- * One of the values defined below are returned. If the returned
- * value is another than ERTS_DSIG_PREP_CONNECTED, the
- * distributed signal cannot be sent before appropriate actions
- * have been taken. Appropriate actions would typically be setting
- * up the connection.
+ * One of the values defined below are returned.
  */
 
-/* Connected; signal can be sent. */
+/* Connected; signals can be enqueued and sent. */
 #define ERTS_DSIG_PREP_CONNECTED	0
 /* Not connected; connection needs to be set up. */
 #define ERTS_DSIG_PREP_NOT_CONNECTED	1
@@ -128,46 +136,80 @@ extern int erts_is_alive;
 #define ERTS_DSIG_PREP_WOULD_SUSPEND	2
 /* System not alive (distributed) */
 #define ERTS_DSIG_PREP_NOT_ALIVE	3
+/* Pending connection; signals can be enqueued */
+#define ERTS_DSIG_PREP_PENDING	        4
 
 ERTS_GLB_INLINE int erts_dsig_prepare(ErtsDSigData *,
-				      DistEntry *,
+				      DistEntry*,
 				      Process *,
+                                      ErtsProcLocks,
 				      ErtsDSigPrepLock,
+				      int,
 				      int);
 
 ERTS_GLB_INLINE
 void erts_schedule_dist_command(Port *, DistEntry *);
 
+int erts_auto_connect(DistEntry* dep, Process *proc, ErtsProcLocks proc_locks);
+
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
 ERTS_GLB_INLINE int 
 erts_dsig_prepare(ErtsDSigData *dsdp,
 		  DistEntry *dep,
 		  Process *proc,
+                  ErtsProcLocks proc_locks,
 		  ErtsDSigPrepLock dspl,
-		  int no_suspend)
+		  int no_suspend,
+		  int connect)
 {
-    int failure;
+    int res;
+
     if (!erts_is_alive)
 	return ERTS_DSIG_PREP_NOT_ALIVE;
-    if (!dep)
-	return ERTS_DSIG_PREP_NOT_CONNECTED;
-    if (dspl == ERTS_DSP_RWLOCK)
-	erts_smp_de_rwlock(dep);
-    else
-	erts_smp_de_rlock(dep);
-    if (ERTS_DE_IS_NOT_CONNECTED(dep)) {
-	failure = ERTS_DSIG_PREP_NOT_CONNECTED;
+    if (!dep) {
+        ASSERT(!connect);
+        return ERTS_DSIG_PREP_NOT_CONNECTED;
+    }
+
+#ifdef ERTS_ENABLE_LOCK_CHECK
+    if (connect) {
+        erts_proc_lc_might_unlock(proc, proc_locks);
+    }
+#endif
+
+retry:
+    erts_de_rlock(dep);
+
+    if (ERTS_DE_IS_CONNECTED(dep)) {
+	res = ERTS_DSIG_PREP_CONNECTED;
+    }
+    else if (dep->status & ERTS_DE_SFLG_PENDING) {
+	res = ERTS_DSIG_PREP_PENDING;
+    }
+    else if (dep->status & ERTS_DE_SFLG_EXITING) {
+	res = ERTS_DSIG_PREP_NOT_CONNECTED;
 	goto fail;
     }
+    else if (connect) {
+        ASSERT(dep->status == 0);
+        erts_de_runlock(dep);
+        if (!erts_auto_connect(dep, proc, proc_locks)) {
+            return ERTS_DSIG_PREP_NOT_ALIVE;
+        }
+	goto retry;
+    }
+    else {
+        ASSERT(dep->status == 0);
+	res = ERTS_DSIG_PREP_NOT_CONNECTED;
+	goto fail;
+    }
+
     if (no_suspend) {
-	failure = ERTS_DSIG_PREP_CONNECTED;
-	erts_smp_mtx_lock(&dep->qlock);
-	if (dep->qflgs & ERTS_DE_QFLG_BUSY)
-	    failure = ERTS_DSIG_PREP_WOULD_SUSPEND;
-	erts_smp_mtx_unlock(&dep->qlock);
-	if (failure == ERTS_DSIG_PREP_WOULD_SUSPEND)
+	if (erts_atomic32_read_acqb(&dep->qflgs) & ERTS_DE_QFLG_BUSY) {
+	    res = ERTS_DSIG_PREP_WOULD_SUSPEND;
 	    goto fail;
+	}
     }
     dsdp->proc = proc;
     dsdp->dep = dep;
@@ -175,16 +217,12 @@ erts_dsig_prepare(ErtsDSigData *dsdp,
     dsdp->connection_id = dep->connection_id;
     dsdp->no_suspend = no_suspend;
     if (dspl == ERTS_DSP_NO_LOCK)
-	erts_smp_de_runlock(dep);
-    return ERTS_DSIG_PREP_CONNECTED;
+	erts_de_runlock(dep);
+    return res;
 
  fail:
-    if (dspl == ERTS_DSP_RWLOCK)
-	erts_smp_de_rwunlock(dep);
-    else
-	erts_smp_de_runlock(dep);
-    return failure;
-
+    erts_de_runlock(dep);
+    return res;
 }
 
 ERTS_GLB_INLINE
@@ -194,7 +232,7 @@ void erts_schedule_dist_command(Port *prt, DistEntry *dist_entry)
     Eterm id;
 
     if (prt) {
-	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+	ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 	ASSERT((erts_atomic32_read_nob(&prt->state)
 		& ERTS_PORT_SFLGS_DEAD) == 0);
 	ASSERT(prt->dist_entry);
@@ -204,7 +242,7 @@ void erts_schedule_dist_command(Port *prt, DistEntry *dist_entry)
     }
     else {
 	ASSERT(dist_entry);
-	ERTS_SMP_LC_ASSERT(erts_lc_rwmtx_is_rlocked(&dist_entry->rwmtx)
+	ERTS_LC_ASSERT(erts_lc_rwmtx_is_rlocked(&dist_entry->rwmtx)
 			   || erts_lc_rwmtx_is_rwlocked(&dist_entry->rwmtx));
 	ASSERT(is_internal_port(dist_entry->cid));
 
@@ -212,7 +250,7 @@ void erts_schedule_dist_command(Port *prt, DistEntry *dist_entry)
 	id = dep->cid;
     }
 
-    if (!erts_smp_atomic_xchg_mb(&dep->dist_cmd_scheduled, 1))
+    if (!erts_atomic_xchg_mb(&dep->dist_cmd_scheduled, 1))
 	erts_port_task_schedule(id, &dep->dist_cmd, ERTS_PORT_TASK_DIST_CMD);
 }
 
@@ -238,7 +276,7 @@ erts_remove_dist_link(ErtsDistLinkData *dldp,
 		      Eterm rid,
 		      DistEntry *dep)
 {
-    erts_smp_de_links_lock(dep);
+    erts_de_links_lock(dep);
     dldp->d_lnk = erts_lookup_link(dep->nlinks, lid);
     if (!dldp->d_lnk)
 	dldp->d_sub_lnk = NULL;
@@ -248,7 +286,7 @@ erts_remove_dist_link(ErtsDistLinkData *dldp,
 		       ? NULL
 		       : erts_remove_link(&dep->nlinks, lid));
     }
-    erts_smp_de_links_unlock(dep);
+    erts_de_links_unlock(dep);
 }
 
 ERTS_GLB_INLINE int
@@ -331,7 +369,7 @@ struct erts_dsig_send_context {
     Eterm ctl;
     Eterm msg;
     int force_busy;
-    Uint32 pass_through_size;
+    Uint32 max_finalize_prepend;
     Uint data_size, dhdr_ext_size;
     ErtsAtomCacheMap *acmp;
     ErtsDistOutputBuf *obuf;
@@ -345,10 +383,12 @@ struct erts_dsig_send_context {
 
 typedef struct {
     int suspend;
+    int connect;
 
     Eterm ctl_heap[6];
     ErtsDSigData dsd;
-    DistEntry* dep_to_deref;
+    DistEntry *dep;
+    int deref_dep;
     struct erts_dsig_send_context dss;
 
     Eterm return_term;
diff --git a/erts/emulator/beam/erl_alloc.c b/erts/emulator/beam/erl_alloc.c
index c7ab444c96..88285d8be6 100644
--- a/erts/emulator/beam/erl_alloc.c
+++ b/erts/emulator/beam/erl_alloc.c
@@ -83,14 +83,6 @@
 #define ERTS_ALC_DEFAULT_ACUL_EHEAP_ALLOC ERTS_ALC_DEFAULT_ENABLED_ACUL_EHEAP_ALLOC
 #define ERTS_ALC_DEFAULT_ACUL_LL_ALLOC ERTS_ALC_DEFAULT_ENABLED_ACUL_LL_ALLOC
 
-#ifndef ERTS_SMP
-#  undef ERTS_ALC_DEFAULT_ACUL
-#  define ERTS_ALC_DEFAULT_ACUL 0
-#  undef ERTS_ALC_DEFAULT_ACUL_EHEAP_ALLOC
-#  define ERTS_ALC_DEFAULT_ACUL_EHEAP_ALLOC 0
-#  undef ERTS_ALC_DEFAULT_ACUL_LL_ALLOC
-#  define ERTS_ALC_DEFAULT_ACUL_LL_ALLOC 0
-#endif
 
 #ifdef DEBUG
 static Uint install_debug_functions(void);
@@ -148,7 +140,7 @@ enum {
 };
 
 typedef struct {
-    erts_smp_atomic32_t refc;
+    erts_atomic32_t refc;
     int only_sz;
     int internal;
     Uint req_sched;
@@ -393,6 +385,7 @@ set_default_temp_alloc_opts(struct au_init *ip)
     SET_DEFAULT_ALLOC_OPTS(ip);
     ip->enable			= AU_ALLOC_DEFAULT_ENABLE(1);
     ip->thr_spec		= 1;
+    ip->disable_allowed         = 0;
     ip->carrier_migration_allowed = 0;
     ip->atype			= AFIT;
     ip->init.util.name_prefix	= "temp_";
@@ -528,7 +521,6 @@ set_default_test_alloc_opts(struct au_init *ip)
 }
 
 
-#ifdef ERTS_SMP
 
 static void
 adjust_tpref(struct au_init *ip, int no_sched)
@@ -551,7 +543,6 @@ adjust_tpref(struct au_init *ip, int no_sched)
     }
 }
 
-#endif
 
 static void handle_args(int *, char **, erts_alc_hndl_args_init_t *);
 
@@ -580,7 +571,6 @@ static void adjust_fix_alloc_sizes(UWord extra_block_size)
     if (extra_block_size && erts_allctrs_info[ERTS_ALC_A_FIXED_SIZE].enabled) {
 	int j;
 
-#ifdef ERTS_SMP
 	if (erts_allctrs_info[ERTS_ALC_A_FIXED_SIZE].thr_spec) {
 	    int i;
 	    ErtsAllocatorThrSpec_t* tspec;
@@ -596,7 +586,6 @@ static void adjust_fix_alloc_sizes(UWord extra_block_size)
 	    }
 	}
 	else
-#endif
 	{
 	    Allctr_t* allctr = erts_allctrs_info[ERTS_ALC_A_FIXED_SIZE].extra;
 	    for (j=0; j < ERTS_ALC_NO_FIXED_SIZES; ++j) {
@@ -619,7 +608,6 @@ strategy_support_carrier_migration(struct au_init *auip)
 static ERTS_INLINE void
 adjust_carrier_migration_support(struct au_init *auip)
 {
-#ifdef ERTS_SMP
     if (auip->init.util.acul) {
 	auip->thr_spec = -1; /* Need thread preferred */
 
@@ -633,9 +621,6 @@ adjust_carrier_migration_support(struct au_init *auip)
 	    auip->init.aoff.flavor = AOFF_BF;
 	}
     }
-#else
-    auip->init.util.acul = 0;
-#endif
 }
 
 void
@@ -660,18 +645,14 @@ erts_alloc_init(int *argc, char **argv, ErtsAllocInitOpts *eaiop)
 	= ERTS_MONITOR_SH_SIZE * sizeof(Uint);
     fix_type_sizes[ERTS_ALC_FIX_TYPE_IX(ERTS_ALC_T_NLINK_SH)]
 	= ERTS_LINK_SH_SIZE * sizeof(Uint);
-    fix_type_sizes[ERTS_ALC_FIX_TYPE_IX(ERTS_ALC_T_DRV_EV_D_STATE)]
-	= sizeof(ErtsDrvEventDataState);
     fix_type_sizes[ERTS_ALC_FIX_TYPE_IX(ERTS_ALC_T_DRV_SEL_D_STATE)]
 	= sizeof(ErtsDrvSelectDataState);
     fix_type_sizes[ERTS_ALC_FIX_TYPE_IX(ERTS_ALC_T_NIF_SEL_D_STATE)]
         = sizeof(ErtsNifSelectDataState);
     fix_type_sizes[ERTS_ALC_FIX_TYPE_IX(ERTS_ALC_T_MSG_REF)]
 	= sizeof(ErtsMessageRef);
-#ifdef ERTS_SMP
     fix_type_sizes[ERTS_ALC_FIX_TYPE_IX(ERTS_ALC_T_THR_Q_EL_SL)]
 	= sizeof(ErtsThrQElement_t);
-#endif
     fix_type_sizes[ERTS_ALC_FIX_TYPE_IX(ERTS_ALC_T_LL_PTIMER)]
 	= erts_timer_type_size(ERTS_ALC_T_LL_PTIMER);
     fix_type_sizes[ERTS_ALC_FIX_TYPE_IX(ERTS_ALC_T_HL_PTIMER)]
@@ -734,20 +715,6 @@ erts_alloc_init(int *argc, char **argv, ErtsAllocInitOpts *eaiop)
 #endif
     }
 
-#ifndef ERTS_SMP
-    init.sl_alloc.thr_spec = 0;
-    init.std_alloc.thr_spec = 0;
-    init.ll_alloc.thr_spec = 0;
-    init.eheap_alloc.thr_spec = 0;
-    init.binary_alloc.thr_spec = 0;
-    init.ets_alloc.thr_spec = 0;
-    init.driver_alloc.thr_spec = 0;
-    init.fix_alloc.thr_spec = 0;
-    init.literal_alloc.thr_spec = 0;
-#ifdef ERTS_ALC_A_EXEC
-    init.exec_alloc.thr_spec = 0;
-#endif
-#endif
 
     /* Make adjustments for carrier migration support */
     init.temp_alloc.init.util.acul = 0;
@@ -798,7 +765,6 @@ erts_alloc_init(int *argc, char **argv, ErtsAllocInitOpts *eaiop)
 #endif
     }
 
-#ifdef ERTS_SMP
     /* Only temp_alloc can use thread specific interface */
     if (init.temp_alloc.thr_spec)
 	init.temp_alloc.thr_spec = erts_no_schedulers;
@@ -817,10 +783,6 @@ erts_alloc_init(int *argc, char **argv, ErtsAllocInitOpts *eaiop)
     adjust_tpref(&init.exec_alloc, erts_no_schedulers);
 #endif
 
-#else
-    /* No thread specific if not smp */
-    init.temp_alloc.thr_spec = 0;
-#endif
 
     /*
      * The following allocators cannot be run with afit strategy.
@@ -839,10 +801,8 @@ erts_alloc_init(int *argc, char **argv, ErtsAllocInitOpts *eaiop)
     refuse_af_strategy(&init.exec_alloc);
 #endif
 
-#ifdef ERTS_SMP 
     if (!init.temp_alloc.thr_spec)
 	refuse_af_strategy(&init.temp_alloc);
-#endif
 
     erts_mtrace_pre_init();
 #if HAVE_ERTS_MSEG
@@ -1006,8 +966,6 @@ set_au_allocator(ErtsAlcType_t alctr_n, struct au_init *init, int ncpu)
 	return;
     }
 
-#ifdef USE_THREADS
-#ifdef ERTS_SMP
     if (init->thr_spec) {
 	if (init->thr_spec > 0) {
 	    af->alloc = erts_alcu_alloc_thr_spec;
@@ -1037,7 +995,6 @@ set_au_allocator(ErtsAlcType_t alctr_n, struct au_init *init, int ncpu)
 	ai->thr_spec	= tspec->size;
     }
     else
-#endif
 	if (init->init.util.ts) {
 	af->alloc = erts_alcu_alloc_ts;
 	if (init->init.util.fix_type_size)
@@ -1049,21 +1006,9 @@ set_au_allocator(ErtsAlcType_t alctr_n, struct au_init *init, int ncpu)
 	af->free = erts_alcu_free_ts;
     }
     else
-#endif
     {
-#ifdef ERTS_SMP
         erts_exit(ERTS_ABORT_EXIT, "%salloc is not thread safe\n",
                  init->init.util.name_prefix);
-#else
-	af->alloc = erts_alcu_alloc;
-	if (init->init.util.fix_type_size)
-	    af->realloc = erts_realloc_fixed_size;
-	else if (init->init.util.ramv)
-	    af->realloc = erts_alcu_realloc_mv;
-	else
-	    af->realloc = erts_alcu_realloc;
-	af->free = erts_alcu_free;
-#endif
     }
     af->extra	= NULL;
     ai->alloc_util	= 1;
@@ -1548,8 +1493,7 @@ handle_args(int *argc, char **argv, erts_alc_hndl_args_init_t *init)
 	&init->ll_alloc,
 	&init->driver_alloc,
 	&init->fix_alloc,
-	&init->sl_alloc,
-	&init->temp_alloc
+	&init->sl_alloc
 	/* test_alloc not affected by +Mea??? or +Mu???  */
     };
     int aui_sz = (int) sizeof(aui)/sizeof(aui[0]);
@@ -1895,9 +1839,7 @@ erts_alloc_register_scheduler(void *vesdp)
     int ix = (int) esdp->no;
     int aix;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     ASSERT(!ERTS_SCHEDULER_IS_DIRTY(esdp));
-#endif
     for (aix = ERTS_ALC_A_MIN; aix <= ERTS_ALC_A_MAX; aix++) {
 	ErtsAllocatorThrSpec_t *tspec = &erts_allctr_thr_spec[aix];
 	esdp->alloc_data.deallctr[aix] = NULL;
@@ -1915,7 +1857,6 @@ erts_alloc_register_scheduler(void *vesdp)
     }
 }
 
-#ifdef ERTS_SMP
 void
 erts_alloc_scheduler_handle_delayed_dealloc(void *vesdp,
 					    int *need_thr_progress,
@@ -1944,12 +1885,10 @@ erts_alloc_scheduler_handle_delayed_dealloc(void *vesdp,
 	}
     }
 }
-#endif
 
 erts_aint32_t
 erts_alloc_fix_alloc_shrink(int ix, erts_aint32_t flgs)
 {
-#ifdef ERTS_SMP
     ErtsAllocatorThrSpec_t *tspec;
     tspec = &erts_allctr_thr_spec[ERTS_ALC_A_FIXED_SIZE];
     if (erts_allctrs_info[ERTS_ALC_A_FIXED_SIZE].thr_spec && tspec->enabled)
@@ -1957,11 +1896,6 @@ erts_alloc_fix_alloc_shrink(int ix, erts_aint32_t flgs)
     if (ix == 0 && erts_allctrs_info[ERTS_ALC_A_FIXED_SIZE].extra)
 	return erts_alcu_fix_alloc_shrink(
 	    erts_allctrs_info[ERTS_ALC_A_FIXED_SIZE].extra, flgs);
-#else
-    if (ix == 1 && erts_allctrs_info[ERTS_ALC_A_FIXED_SIZE].extra)
-	return erts_alcu_fix_alloc_shrink(
-	    erts_allctrs_info[ERTS_ALC_A_FIXED_SIZE].extra, flgs);
-#endif
     return 0;
 }
 
@@ -2165,7 +2099,7 @@ erts_memory(fmtfn_t *print_to_p, void *print_to_arg, void *proc, Eterm earg)
     int only_one_value = 0;
     ErtsAlcUFixInfo_t fi[ERTS_ALC_NO_FIXED_SIZES] = {{0,0}};
 
-    ERTS_SMP_LC_ASSERT(erts_smp_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
 
     /* Figure out whats wanted... */
 
@@ -2338,10 +2272,10 @@ erts_memory(fmtfn_t *print_to_p, void *print_to_arg, void *proc, Eterm earg)
 
 
     if (proc) {
-	ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN
+	ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN
 			   == erts_proc_lc_my_proc_locks(proc));
 	/* We'll need locks early in the lock order */
-	erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
     }
 
     /* Calculate values needed... */
@@ -2499,7 +2433,7 @@ erts_memory(fmtfn_t *print_to_p, void *print_to_arg, void *proc, Eterm earg)
 	Uint *hp;
 	Uint hsz;
 
-	erts_smp_proc_lock(proc, ERTS_PROC_LOCK_MAIN);
+	erts_proc_lock(proc, ERTS_PROC_LOCK_MAIN);
 
 	if (only_one_value) {
 	    ASSERT(length == 1);
@@ -2548,11 +2482,11 @@ erts_allocated_areas(fmtfn_t *print_to_p, void *print_to_arg, void *proc)
     Uint reserved_atom_space, atom_space;
 
     if (proc) {
-	ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN
+	ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN
 			   == erts_proc_lc_my_proc_locks(proc));
 
 	/* We'll need locks early in the lock order */
-	erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
     }
 
     i = 0;
@@ -2704,7 +2638,7 @@ erts_allocated_areas(fmtfn_t *print_to_p, void *print_to_arg, void *proc)
 	Uint hsz;
 	Uint *hszp;
 
-	erts_smp_proc_lock(proc, ERTS_PROC_LOCK_MAIN);
+	erts_proc_lock(proc, ERTS_PROC_LOCK_MAIN);
 
 	hpp = NULL;
 	hsz = 0;
@@ -2792,7 +2726,7 @@ erts_allocator_info(fmtfn_t to, void *arg)
 {
     ErtsAlcType_t a;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
 
     for (a = ERTS_ALC_A_MIN; a <= ERTS_ALC_A_MAX; a++) {
 	int ai;
@@ -2845,11 +2779,7 @@ erts_allocator_info(fmtfn_t to, void *arg)
 #if HAVE_ERTS_MSEG
     {
 	struct erts_mmap_info_struct emis;
-#ifdef ERTS_SMP
 	int max = (int) erts_no_schedulers;
-#else
-	int max = 0;
-#endif
 	int i;
 	for (i = 0; i <= max; i++) {
 	    erts_print(to, arg, "=allocator:mseg_alloc[%d]\n", i);
@@ -3310,7 +3240,7 @@ reply_alloc_info(void *vair)
 	    case ERTS_ALC_INFO_A_DISABLED_EXEC:
 		break;
 	    case ERTS_ALC_INFO_A_MSEG_ALLOC:
-#if HAVE_ERTS_MSEG && defined(ERTS_SMP)
+#if HAVE_ERTS_MSEG
 		alloc_atom = erts_bld_atom(hpp, szp, "mseg_alloc");
 		ainfo = erts_mseg_info(sched_id, NULL, NULL,
                                        hpp != NULL, air->only_sz, hpp, szp);
@@ -3364,10 +3294,10 @@ reply_alloc_info(void *vair)
     if (air->req_sched == sched_id)
 	rp_locks &= ~ERTS_PROC_LOCK_MAIN;
  
-    erts_smp_proc_unlock(rp, rp_locks);
+    erts_proc_unlock(rp, rp_locks);
     erts_proc_dec_refc(rp);
 
-    if (erts_smp_atomic32_dec_read_nob(&air->refc) == 0) {
+    if (erts_atomic32_dec_read_nob(&air->refc) == 0) {
         erts_iref_storage_clean(&air->iref);
 	aireq_free(air);
     }
@@ -3446,18 +3376,16 @@ erts_request_alloc_info(struct process *c_p,
 
     air->allocs[airix] = ERTS_ALC_A_INVALID;
 
-    erts_smp_atomic32_init_nob(&air->refc,
+    erts_atomic32_init_nob(&air->refc,
 			       (erts_aint32_t) erts_no_schedulers);
 
     erts_proc_add_refc(c_p, (Sint) erts_no_schedulers);
 
-#ifdef ERTS_SMP
     if (erts_no_schedulers > 1)
 	erts_schedule_multi_misc_aux_work(1,
 					  erts_no_schedulers,
 					  reply_alloc_info,
 					  (void *) air);
-#endif
 
     reply_alloc_info((void *) air);
 
@@ -3532,35 +3460,29 @@ UWord erts_alc_test(UWord op, UWord a1, UWord a2, UWord a3)
     case 0xf:
 	switch (op) {
 	case 0xf00:
-#ifdef USE_THREADS
 	    if (((Allctr_t *) a1)->thread_safe)
 		return (UWord) erts_alcu_alloc_ts(ERTS_ALC_T_UNDEF,
 							  (void *) a1,
 							  (Uint) a2);
 	    else
-#endif
 		return (UWord) erts_alcu_alloc(ERTS_ALC_T_UNDEF,
 						       (void *) a1,
 						       (Uint) a2);
 	case 0xf01:
-#ifdef USE_THREADS
 	    if (((Allctr_t *) a1)->thread_safe)
 		return (UWord) erts_alcu_realloc_ts(ERTS_ALC_T_UNDEF,
 							    (void *) a1,
 							    (void *) a2,
 							    (Uint) a3);
 	    else
-#endif
 		return (UWord) erts_alcu_realloc(ERTS_ALC_T_UNDEF,
 							 (void *) a1,
 							 (void *) a2,
 							 (Uint) a3);
 	case 0xf02:
-#ifdef USE_THREADS
 	    if (((Allctr_t *) a1)->thread_safe)
 		erts_alcu_free_ts(ERTS_ALC_T_UNDEF, (void *) a1, (void *) a2);
 	    else
-#endif
 		erts_alcu_free(ERTS_ALC_T_UNDEF, (void *) a1, (void *) a2);
 	    return 0;
 	case 0xf03: {
@@ -3571,11 +3493,7 @@ UWord erts_alc_test(UWord op, UWord a1, UWord a2, UWord a3)
 	    init.enable = 1;
 	    init.atype = GOODFIT;
 	    init.init.util.name_prefix = (char *) a1;
-#ifdef ERTS_SMP
 	    init.init.util.ts = 1;
-#else
-            init.init.util.ts = a2 ? 1 : 0;
-#endif
 	    if ((char **) a3) {
 		char **argv = (char **) a3;
 		int i = 0;
@@ -3630,7 +3548,6 @@ UWord erts_alc_test(UWord op, UWord a1, UWord a2, UWord a3)
 	    erts_alcu_stop((Allctr_t *) a1);
 	    erts_free(ERTS_ALC_T_UNDEF, (void *) a1);
 	    break;
-#ifdef USE_THREADS
 	case 0xf05: return (UWord) 1;
 	case 0xf06: return (UWord) ((Allctr_t *) a1)->thread_safe;
 #ifdef ETHR_NO_FORKSAFETY
@@ -3700,12 +3617,7 @@ UWord erts_alc_test(UWord op, UWord a1, UWord a2, UWord a3)
 	    ethr_thr_exit((void *) a1);
 	    ERTS_ALC_TEST_ABORT;
 	    break;
-#endif /* #ifdef USE_THREADS */
-#ifdef ERTS_SMP
 	case 0xf13: return (UWord) 1;
-#else
-	case 0xf13: return (UWord) 0;
-#endif
 	case 0xf14: return (UWord) erts_alloc(ERTS_ALC_T_TEST, (Uint)a1);
 
 	case 0xf15: erts_free(ERTS_ALC_T_TEST, (void*)a1); return 0;
@@ -3909,10 +3821,8 @@ void check_allocators(void)
 	    ErtsAllocatorFunctions_t *real_af = (ErtsAllocatorFunctions_t *) erts_allctrs[i].extra;
 	    Allctr_t *allctr = real_af->extra;
 	    Carrier_t *ct;
-#ifdef USE_THREADS
 	if (allctr->thread_safe)
 	    erts_mtx_lock(&allctr->mutex);
-#endif
 
 	    if (allctr->check_mbc) {
 		for (ct = allctr->mbc_list.first; ct; ct = ct->next) {
@@ -3920,10 +3830,8 @@ void check_allocators(void)
 		    allctr->check_mbc(allctr,ct);
 		}
 	    }
-#ifdef USE_THREADS
 	if (allctr->thread_safe)
 	    erts_mtx_unlock(&allctr->mutex);
-#endif
 	}
     }
 }
diff --git a/erts/emulator/beam/erl_alloc.h b/erts/emulator/beam/erl_alloc.h
index 97a1cf1308..117f96a4ad 100644
--- a/erts/emulator/beam/erl_alloc.h
+++ b/erts/emulator/beam/erl_alloc.h
@@ -27,9 +27,7 @@
 #include "erl_thr_progress.h"
 #undef ERL_THR_PROGRESS_TSD_TYPE_ONLY
 #include "erl_alloc_util.h"
-#ifdef USE_THREADS
 #include "erl_threads.h"
-#endif
 #include "erl_mmap.h"
 
 #ifdef DEBUG
@@ -154,12 +152,10 @@ void erts_allctr_wrapper_pre_lock(void);
 void erts_allctr_wrapper_pre_unlock(void);
 
 void erts_alloc_register_scheduler(void *vesdp);
-#ifdef ERTS_SMP
 void erts_alloc_scheduler_handle_delayed_dealloc(void *vesdp,
 						 int *need_thr_progress,
 						 ErtsThrPrgrVal *thr_prgr_p,
 						 int *more_work);
-#endif
 erts_aint32_t erts_alloc_fix_alloc_shrink(int ix, erts_aint32_t flgs);
 
 __decl_noreturn void erts_alloc_enomem(ErtsAlcType_t,Uint)		
@@ -338,37 +334,10 @@ erts_alloc_get_verify_unused_temp_alloc(Allctr_t **allctr);
   (((((SZ) - 1) / ERTS_CACHE_LINE_SIZE) + 1) * ERTS_CACHE_LINE_SIZE)
 
 #define ERTS_QUALLOC_IMPL(NAME, TYPE, PASZ, ALCT)			\
-ERTS_QUICK_ALLOC_IMPL(NAME, TYPE, PASZ, ALCT,				\
-		      (void) 0, (void) 0, (void) 0)
-
-#define ERTS_SMP_QUALLOC_IMPL(NAME, TYPE, PASZ, ALCT)			\
-static erts_smp_spinlock_t NAME##_lck;					\
-ERTS_QUICK_ALLOC_IMPL(NAME, TYPE, PASZ, ALCT,				\
-		      erts_smp_spinlock_init(&NAME##_lck, #NAME "_alloc_lock", NIL, \
-		          ERTS_LOCK_FLAGS_CATEGORY_ALLOCATOR),\
-		      erts_smp_spin_lock(&NAME##_lck),			\
-		      erts_smp_spin_unlock(&NAME##_lck))
-
-#ifdef ERTS_SMP
+    ERTS_QUICK_ALLOC_IMPL(NAME, TYPE, PASZ, ALCT, (void) 0, (void) 0, (void) 0)
 
 #define ERTS_TS_QUALLOC_IMPL(NAME, TYPE, PASZ, ALCT)			\
-ERTS_SMP_QUALLOC_IMPL(NAME, TYPE, PASZ, ALCT)
-
-#else /* !ERTS_SMP */
-
-#define ERTS_TS_QUALLOC_IMPL(NAME, TYPE, PASZ, ALCT)			\
-static erts_mtx_t NAME##_lck;						\
-ERTS_QUICK_ALLOC_IMPL(NAME, TYPE, PASZ, ALCT,				\
-		      erts_mtx_init(NAME##_lck, #NAME "_alloc_lock", NIL, \
-		          ERTS_LOCK_FLAGS_CATEGORY_ALLOCATOR),\
-		      erts_mtx_lock(&NAME##_lck),			\
-		      erts_mtx_unlock(&NAME##_lck))
-
-
-#endif
-
-#define ERTS_PALLOC_IMPL(NAME, TYPE, PASZ)				\
-ERTS_PRE_ALLOC_IMPL(NAME, TYPE, PASZ, (void) 0, (void) 0, (void) 0)
+ERTS_QUALLOC_IMPL(NAME, TYPE, PASZ, ALCT)
 
 #define ERTS_TS_PALLOC_IMPL(NAME, TYPE, PASZ)				\
 static erts_spinlock_t NAME##_lck;					\
@@ -378,17 +347,10 @@ ERTS_PRE_ALLOC_IMPL(NAME, TYPE, PASZ,					\
 		    erts_spin_lock(&NAME##_lck),			\
 		    erts_spin_unlock(&NAME##_lck))
 
-#ifdef ERTS_SMP
 
-#define ERTS_SMP_PALLOC_IMPL(NAME, TYPE, PASZ)				\
+#define ERTS_PALLOC_IMPL(NAME, TYPE, PASZ)				\
   ERTS_TS_PALLOC_IMPL(NAME, TYPE, PASZ)
 
-#else /* !ERTS_SMP */
-
-#define ERTS_SMP_PALLOC_IMPL(NAME, TYPE, PASZ)				\
-  ERTS_PALLOC_IMPL(NAME, TYPE, PASZ)
-
-#endif
 
 #define ERTS_QUICK_ALLOC_IMPL(NAME, TYPE, PASZ, ALCT, ILCK, LCK, ULCK)	\
 ERTS_PRE_ALLOC_IMPL(NAME##_pre, TYPE, PASZ, ILCK, LCK, ULCK)		\
@@ -412,21 +374,11 @@ NAME##_free(TYPE *p)							\
 	erts_free(ALCT, (void *) p);					\
 }
 
-#ifdef ERTS_SMP
 #define ERTS_SCHED_PREF_PALLOC_IMPL(NAME, TYPE, PASZ)			\
   ERTS_SCHED_PREF_PRE_ALLOC_IMPL(NAME, TYPE, PASZ)
-#else
-#define ERTS_SCHED_PREF_PALLOC_IMPL(NAME, TYPE, PASZ)			\
-  ERTS_PRE_ALLOC_IMPL(NAME, TYPE, PASZ, (void) 0, (void) 0, (void) 0)
-#endif
 
-#ifdef ERTS_SMP
 #define ERTS_SCHED_PREF_AUX(NAME, TYPE, PASZ)				\
 ERTS_SCHED_PREF_PRE_ALLOC_IMPL(NAME##_pre, TYPE, PASZ)
-#else
-#define ERTS_SCHED_PREF_AUX(NAME, TYPE, PASZ)				\
-ERTS_PRE_ALLOC_IMPL(NAME##_pre, TYPE, PASZ, (void) 0, (void) 0, (void) 0)
-#endif
 
 #define ERTS_SCHED_PREF_QUICK_ALLOC_IMPL(NAME, TYPE, PASZ, ALCT)	\
 ERTS_SCHED_PREF_AUX(NAME, TYPE, PASZ)					\
@@ -450,6 +402,32 @@ NAME##_free(TYPE *p)							\
 	erts_free(ALCT, (void *) p);					\
 }
 
+#define ERTS_THR_PREF_AUX(NAME, TYPE, PASZ)				\
+ERTS_THR_PREF_PRE_ALLOC_IMPL(NAME##_pre, TYPE, PASZ)
+
+#define ERTS_THR_PREF_QUICK_ALLOC_IMPL(NAME, TYPE, PASZ, ALCT)	        \
+ERTS_THR_PREF_AUX(NAME, TYPE, PASZ)					\
+static void								\
+init_##NAME##_alloc(int nthreads)					\
+{									\
+    init_##NAME##_pre_alloc(nthreads);			                \
+}									\
+static ERTS_INLINE TYPE *						\
+NAME##_alloc(void)							\
+{									\
+    TYPE *res = NAME##_pre_alloc();					\
+    if (!res)								\
+	res = erts_alloc(ALCT, sizeof(TYPE));				\
+    return res;								\
+}									\
+static ERTS_INLINE void							\
+NAME##_free(TYPE *p)							\
+{									\
+    if (!NAME##_pre_free(p))						\
+	erts_free(ALCT, (void *) p);					\
+}
+
+
 #ifdef DEBUG
 #define ERTS_PRE_ALLOC_SIZE(SZ) ((SZ) < 1000 ? (SZ)/10 + 10 : 100)
 #define ERTS_PRE_ALLOC_CLOBBER(P, T) memset((void *) (P), 0xfd, sizeof(T))
@@ -530,7 +508,8 @@ init_##NAME##_alloc(void)						\
 {									\
     sspa_data_##NAME##__ =						\
 	erts_sspa_create(sizeof(union erts_sspa_##NAME##__),		\
-			 ERTS_PRE_ALLOC_SIZE((PASZ)));			\
+			 ERTS_PRE_ALLOC_SIZE((PASZ)), 			\
+                         0, NULL);                                      \
 }									\
 									\
 static TYPE *								\
@@ -552,6 +531,57 @@ NAME##_free(TYPE *p)							\
 			  (char *) p);					\
 }
 
+
+#define ERTS_THR_PREF_PRE_ALLOC_IMPL(NAME, TYPE, PASZ)		        \
+union erts_sspa_##NAME##__ {						\
+    erts_sspa_blk_t next;						\
+    TYPE type;								\
+};									\
+									\
+static erts_sspa_data_t *sspa_data_##NAME##__;				\
+									\
+static void								\
+init_##NAME##_alloc(int nthreads)					\
+{									\
+    sspa_data_##NAME##__ =						\
+	erts_sspa_create(sizeof(union erts_sspa_##NAME##__),		\
+			 ERTS_PRE_ALLOC_SIZE((PASZ)),			\
+                         nthreads,                                      \
+                         #NAME);                                        \
+}									\
+                                                                        \
+void								        \
+erts_##NAME##_alloc_init_thread(void)				        \
+{									\
+    int id = erts_atomic_inc_read_nob(&sspa_data_##NAME##__->id_generator);\
+    if (id > sspa_data_##NAME##__->nthreads) {                          \
+        erts_exit(ERTS_ABORT_EXIT,                                      \
+                  "%s:%d:%s(): Too many threads for '" #NAME "'\n",     \
+                  __FILE__, __LINE__, __func__);                        \
+    }                                                                   \
+    erts_tsd_set(sspa_data_##NAME##__->tsd_key, (void*)(SWord)id);      \
+}									\
+									\
+static TYPE *								\
+NAME##_alloc(void)							\
+{									\
+    int id = (int)(SWord)erts_tsd_get(sspa_data_##NAME##__->tsd_key);   \
+    if (id == 0)                                                        \
+        return NULL;                                                    \
+    return (TYPE *) erts_sspa_alloc(sspa_data_##NAME##__,		\
+                                    id-1);		                \
+}									\
+									\
+static int								\
+NAME##_free(TYPE *p)							\
+{									\
+    int id = (int)(SWord)erts_tsd_get(sspa_data_##NAME##__->tsd_key);   \
+    return erts_sspa_free(sspa_data_##NAME##__,				\
+			  id - 1,		                        \
+			  (char *) p);					\
+}
+
+
 #ifdef DEBUG
 #define ERTS_ALC_DBG_BLK_SZ(PTR) (*(((UWord *) (PTR)) - 2))
 #endif /* #ifdef DEBUG */
diff --git a/erts/emulator/beam/erl_alloc.types b/erts/emulator/beam/erl_alloc.types
index 252bf1cc7e..c6cc5c78b3 100644
--- a/erts/emulator/beam/erl_alloc.types
+++ b/erts/emulator/beam/erl_alloc.types
@@ -53,15 +53,6 @@
 #
 # IMPORTANT! Only use 7-bit ascii text in this file!
 
-+if smp
-+disable threads_no_smp
-+else
-+if threads
-+enable threads_no_smp
-+else
-+disable threads_no_smp
-+endif
-+endif
 
 # --- Allocator declarations -------------------------------------------------
 #
@@ -77,8 +68,6 @@
 
 allocator	SYSTEM		true		sys_alloc
 
-+if smp
-
 allocator	TEMPORARY	true		temp_alloc
 allocator	SHORT_LIVED	true		sl_alloc
 allocator	STANDARD	true		std_alloc
@@ -91,22 +80,6 @@ allocator	LITERAL 	true		literal_alloc
 allocator	EXEC     	true	        exec_alloc
 +endif
 
-+else # Non smp build
-
-allocator	TEMPORARY	false		temp_alloc
-allocator	SHORT_LIVED	false		sl_alloc
-allocator	STANDARD	false		std_alloc
-allocator	LONG_LIVED	false		ll_alloc
-allocator	EHEAP		false		eheap_alloc
-allocator	ETS		false		ets_alloc
-allocator	FIXED_SIZE	false		fix_alloc
-allocator	LITERAL 	false		literal_alloc
-+if exec_alloc
-allocator	EXEC     	false	        exec_alloc
-+endif
-
-+endif
-
 allocator	BINARY		true		binary_alloc
 allocator	DRIVER		true		driver_alloc
 
@@ -285,33 +258,21 @@ type    MREF_ENT	STANDARD	SYSTEM		magic_ref_entry
 type	MREF_TAB_BKTS	STANDARD	SYSTEM		magic_ref_table_buckets
 type	MREF_TAB	LONG_LIVED	SYSTEM		magic_ref_table
 type	MINDIRECTION	FIXED_SIZE	SYSTEM		magic_indirection
+type	BINARY_FIND	SHORT_LIVED	PROCESSES	binary_find
+type  	OPEN_PORT_ENV 	TEMPORARY	SYSTEM		open_port_env
 type	CRASH_DUMP	STANDARD	SYSTEM		crash_dump
+type	DIST_TRANSCODE  SHORT_LIVED	SYSTEM		dist_transcode_context
 
-+if threads_no_smp
-# Need thread safe allocs, but std_alloc and fix_alloc are not;
-# use driver_alloc which is...
-type	THR_Q_EL	DRIVER 	   	SYSTEM		thr_q_element
-type	THR_Q_EL_SL	DRIVER		SYSTEM		sl_thr_q_element
-type	MISC_AUX_WORK	DRIVER		SYSTEM		misc_aux_work
-+else
 type	THR_Q_EL	STANDARD   	SYSTEM		thr_q_element
 type	THR_Q_EL_SL	FIXED_SIZE	SYSTEM		sl_thr_q_element
 type	MISC_AUX_WORK	SHORT_LIVED	SYSTEM		misc_aux_work
-+endif
 type	THR_Q		STANDARD	SYSTEM		thr_queue
 type	THR_Q_SL	SHORT_LIVED	SYSTEM		short_lived_thr_queue
 type	THR_Q_LL	LONG_LIVED	SYSTEM		long_lived_thr_queue
 
-+if smp
 type	ASYNC		SHORT_LIVED	SYSTEM		async
 type	ZLIB		STANDARD	SYSTEM		zlib
-+else
-# sl/std_alloc is not thread safe in non smp build; therefore, we use driver_alloc
-type	ZLIB		DRIVER   	SYSTEM		zlib
-type	ASYNC		DRIVER		SYSTEM		async
-+endif
 
-+if smp
 type	PORT_LOCK	STANDARD	SYSTEM		port_lock
 type	DRIVER_LOCK	STANDARD	SYSTEM		driver_lock
 type	XPORTS_LIST	SHORT_LIVED	SYSTEM		extra_port_list
@@ -321,33 +282,19 @@ type	THR_PRGR_IDATA	LONG_LIVED	SYSTEM		thr_prgr_internal_data
 type	THR_PRGR_DATA	LONG_LIVED	SYSTEM		thr_prgr_data
 type	T_THR_PRGR_DATA	SHORT_LIVED	SYSTEM		temp_thr_prgr_data
 type	RELEASE_LAREA	SHORT_LIVED	SYSTEM		release_literal_area
-+endif
 
 #
 # Types used for special emulators
 #
 
-+if threads
-
 type	ETHR_STD	STANDARD	SYSTEM		ethread_standard
 type	ETHR_SL		SHORT_LIVED	SYSTEM		ethread_short_lived
 type	ETHR_LL		LONG_LIVED	SYSTEM		ethread_long_lived
 
-+endif
-
-+if shared_heap
-
-type	STACK		STANDARD	PROCESSES	stack
-type	ACTIVE_PROCS	STANDARD	PROCESSES	active_procs
-
-+endif
-
-+if smp
 type	SYS_MSG_Q	SHORT_LIVED	PROCESSES	system_messages_queue
 type	FP_EXCEPTION	LONG_LIVED	SYSTEM		fp_exception
 type	LL_MPATHS	LONG_LIVED	SYSTEM		ll_migration_paths
 type	SL_MPATHS	SHORT_LIVED	SYSTEM		sl_migration_paths
-+endif
 
 +if hipe
 
@@ -361,8 +308,6 @@ type	HIPE_EXEC	EXEC            CODE		hipe_code
 
 +endif
 
-
-
 +if heap_frag_elim_test
 
 type	SSB		SHORT_LIVED	PROCESSES	ssb
@@ -409,11 +354,9 @@ type	SYS_CHECK_REQ	SHORT_LIVED	SYSTEM		system_check_request
 type  	TEMP_TERM 	TEMPORARY	SYSTEM		temp_term
 type	DRV_TAB		LONG_LIVED	SYSTEM		drv_tab
 type	DRV_EV_STATE	LONG_LIVED	SYSTEM		driver_event_state
-type	DRV_EV_D_STATE	FIXED_SIZE	SYSTEM		driver_event_data_state
 type	DRV_SEL_D_STATE	FIXED_SIZE	SYSTEM		driver_select_data_state
 type	NIF_SEL_D_STATE	FIXED_SIZE	SYSTEM		enif_select_data_state
 type	FD_LIST		SHORT_LIVED	SYSTEM		fd_list
-type	ACTIVE_FD_ARR	SHORT_LIVED	SYSTEM		active_fd_array
 type	POLLSET		LONG_LIVED	SYSTEM		pollset
 type	POLLSET_UPDREQ	SHORT_LIVED	SYSTEM		pollset_update_req
 type	POLL_FDS	LONG_LIVED	SYSTEM		poll_fds
@@ -432,11 +375,7 @@ type	PUTENV_STR	SYSTEM		SYSTEM		putenv_string
 type	PRT_REP_EXIT	STANDARD	SYSTEM		port_report_exit
 type	SYS_BLOCKING	STANDARD	SYSTEM		sys_blocking
 
-+if smp
 type	SYS_WRITE_BUF	TEMPORARY	SYSTEM		sys_write_buf
-+else
-type	SYS_WRITE_BUF	BINARY		SYSTEM		sys_write_buf
-+endif
 
 +endif
 
diff --git a/erts/emulator/beam/erl_alloc_util.c b/erts/emulator/beam/erl_alloc_util.c
index af86ad0548..4d4bddb93f 100644
--- a/erts/emulator/beam/erl_alloc_util.c
+++ b/erts/emulator/beam/erl_alloc_util.c
@@ -305,9 +305,6 @@ MBC after deallocating first block:
 #  define ERTS_ALC_CPOOL_DEBUG
 #endif
 
-#ifndef ERTS_SMP
-#  undef ERTS_ALC_CPOOL_DEBUG
-#endif
 
 #ifdef ERTS_ALC_CPOOL_DEBUG
 #  define ERTS_ALC_CPOOL_ASSERT(A)				\
@@ -322,13 +319,8 @@ MBC after deallocating first block:
 #  define ERTS_ALC_CPOOL_ASSERT(A) ((void) 1)
 #endif
 
-#ifdef ERTS_SMP
 #define ERTS_ALC_IS_CPOOL_ENABLED(A)	((A)->cpool.util_limit)
-#else
-#define ERTS_ALC_IS_CPOOL_ENABLED(A)	(0)
-#endif
 
-#ifdef ERTS_SMP
 
 #define ERTS_ALC_CPOOL_MAX_DISABLE_ABANDON		1000
 #define ERTS_ALC_CPOOL_ALLOC_OP_INC			8
@@ -367,28 +359,16 @@ do {										\
     }										\
 } while (0)
 
-#else
-#define ERTS_ALC_CPOOL_ALLOC_OP(A)
-#define ERTS_ALC_CPOOL_REALLOC_OP(A)
-#define ERTS_ALC_CPOOL_FREE_OP(A)
-#endif
 
 #define ERTS_CRR_ALCTR_FLG_IN_POOL	(((erts_aint_t) 1) << 0)
 #define ERTS_CRR_ALCTR_FLG_BUSY		(((erts_aint_t) 1) << 1)
 #define ERTS_CRR_ALCTR_FLG_MASK (ERTS_CRR_ALCTR_FLG_IN_POOL | \
                                  ERTS_CRR_ALCTR_FLG_BUSY)
 
-#ifdef ERTS_SMP
 #define SBC_HEADER_SIZE	   						\
     (UNIT_CEILING(offsetof(Carrier_t, cpool)                            \
 	          + ABLK_HDR_SZ)	                                \
      - ABLK_HDR_SZ)
-#else
-#define SBC_HEADER_SIZE	   						\
-    (UNIT_CEILING(sizeof(Carrier_t)					\
-		  + ABLK_HDR_SZ)					\
-     - ABLK_HDR_SZ)
-#endif
 #define MBC_HEADER_SIZE(AP) ((AP)->mbc_header_size)
 
 
@@ -402,7 +382,7 @@ do {										\
 
 #define SET_CARRIER_HDR(C, Sz, F, AP) \
   (ASSERT(((Sz) & FLG_MASK) == 0), (C)->chdr = ((Sz) | (F)), \
-   erts_smp_atomic_init_nob(&(C)->allctr, (erts_aint_t) (AP)))
+   erts_atomic_init_nob(&(C)->allctr, (erts_aint_t) (AP)))
 
 #define BLK_TO_SBC(B) \
   ((Carrier_t *) (((char *) (B)) - SBC_HEADER_SIZE))
@@ -598,15 +578,11 @@ do {									\
     (AP)->mbcs.blocks.curr.size -= (CRR)->cpool.blocks_size;		\
 } while (0)
 
-#ifdef ERTS_SMP
 #define STAT_MBC_BLK_ALLOC_CRR(CRR, BSZ)				\
 do {									\
     (CRR)->cpool.blocks++;						\
     (CRR)->cpool.blocks_size += (BSZ);					\
 } while (0)
-#else
-#define STAT_MBC_BLK_ALLOC_CRR(CRR, BSZ) ((void) (CRR)) /* Get rid of warning */
-#endif
 
 #define STAT_MBC_BLK_ALLOC(AP, CRR, BSZ, FLGS)	       			\
 do {									\
@@ -626,7 +602,6 @@ stat_cpool_mbc_blk_free(Allctr_t *allctr,
 			Carrier_t **busy_pcrr_pp,
 			UWord blksz)
 {
-#ifdef ERTS_SMP
 
     ERTS_ALC_CPOOL_ASSERT(crr->cpool.blocks > 0);
     crr->cpool.blocks--;
@@ -651,9 +626,6 @@ stat_cpool_mbc_blk_free(Allctr_t *allctr,
 #endif
 
     return 1;
-#else
-    return 0;
-#endif
 }
 
 #define STAT_MBC_BLK_FREE(AP, CRR, BPCRRPP, BSZ, FLGS)			\
@@ -689,12 +661,7 @@ do {									\
 #endif
 
 #ifdef DEBUG
-#ifdef USE_THREADS
-# ifdef ERTS_SMP
 #  define IS_ACTUALLY_BLOCKING (erts_thr_progress_is_blocking())
-# else
-#  define IS_ACTUALLY_BLOCKING 0
-# endif
 #define ERTS_ALCU_DBG_CHK_THR_ACCESS(A)					\
 do {									\
     if (!(A)->thread_safe && !IS_ACTUALLY_BLOCKING) {                   \
@@ -703,7 +670,7 @@ do {									\
 	    (A)->debug.saved_tid = 1;					\
 	}								\
 	else {								\
-	    ERTS_SMP_LC_ASSERT(						\
+	    ERTS_LC_ASSERT(						\
 		ethr_equal_tids((A)->debug.tid, erts_thr_self()));	\
 	}								\
     }									\
@@ -711,9 +678,6 @@ do {									\
 #else
 #define ERTS_ALCU_DBG_CHK_THR_ACCESS(A)
 #endif
-#else
-#define ERTS_ALCU_DBG_CHK_THR_ACCESS(A)
-#endif
 
 static void make_name_atoms(Allctr_t *allctr);
 
@@ -862,7 +826,7 @@ erts_alcu_literal_32_mseg_alloc(Allctr_t *allctr, Uint *size_p, Uint flags)
     Uint sz = ERTS_SUPERALIGNED_CEILING(*size_p);
     ERTS_LC_ASSERT(allctr->alloc_no == ERTS_ALC_A_LITERAL &&
                    allctr->t == 0);
-    ERTS_SMP_LC_ASSERT(allctr->thread_safe);
+    ERTS_LC_ASSERT(allctr->thread_safe);
 
     res = erts_alcu_mseg_alloc(allctr, &sz, flags);
     if (res) {
@@ -880,7 +844,7 @@ erts_alcu_literal_32_mseg_realloc(Allctr_t *allctr, void *seg,
     Uint new_sz = ERTS_SUPERALIGNED_CEILING(*new_size_p);
     ERTS_LC_ASSERT(allctr->alloc_no == ERTS_ALC_A_LITERAL &&
                    allctr->t == 0);
-    ERTS_SMP_LC_ASSERT(allctr->thread_safe);
+    ERTS_LC_ASSERT(allctr->thread_safe);
 
     if (seg && old_size)
         clear_literal_range(seg, old_size);
@@ -898,7 +862,7 @@ erts_alcu_literal_32_mseg_dealloc(Allctr_t *allctr, void *seg, Uint size,
 {
     ERTS_LC_ASSERT(allctr->alloc_no == ERTS_ALC_A_LITERAL &&
                    allctr->t == 0);
-    ERTS_SMP_LC_ASSERT(allctr->thread_safe);
+    ERTS_LC_ASSERT(allctr->thread_safe);
 
     erts_alcu_mseg_dealloc(allctr, seg, size, flags);
 
@@ -1058,7 +1022,7 @@ erts_alcu_literal_32_sys_alloc(Allctr_t *allctr, Uint* size_p, int superalign)
     Uint size = ERTS_SUPERALIGNED_CEILING(*size_p);
     ERTS_LC_ASSERT(allctr->alloc_no == ERTS_ALC_A_LITERAL &&
                    allctr->t == 0);
-    ERTS_SMP_LC_ASSERT(allctr->thread_safe);
+    ERTS_LC_ASSERT(allctr->thread_safe);
 
     res = erts_alcu_sys_alloc(allctr, &size, 1);
     if (res) {
@@ -1076,7 +1040,7 @@ erts_alcu_literal_32_sys_realloc(Allctr_t *allctr, void *ptr, Uint* size_p, Uint
 
     ERTS_LC_ASSERT(allctr->alloc_no == ERTS_ALC_A_LITERAL &&
                    allctr->t == 0);
-    ERTS_SMP_LC_ASSERT(allctr->thread_safe);
+    ERTS_LC_ASSERT(allctr->thread_safe);
 
     if (ptr && old_size)
         clear_literal_range(ptr, old_size);
@@ -1093,7 +1057,7 @@ erts_alcu_literal_32_sys_dealloc(Allctr_t *allctr, void *ptr, Uint size, int sup
 {
     ERTS_LC_ASSERT(allctr->alloc_no == ERTS_ALC_A_LITERAL &&
                    allctr->t == 0);
-    ERTS_SMP_LC_ASSERT(allctr->thread_safe);
+    ERTS_LC_ASSERT(allctr->thread_safe);
 
     erts_alcu_sys_dealloc(allctr, ptr, size, 1);
 
@@ -1191,7 +1155,6 @@ unlink_carrier(CarrierList_t *cl, Carrier_t *crr)
     }
 }
 
-#ifdef ERTS_SMP
 
 #ifdef DEBUG
 static int is_in_list(ErtsDoubleLink_t* sentinel, ErtsDoubleLink_t* node)
@@ -1292,16 +1255,15 @@ clear_busy_pool_carrier(Allctr_t *allctr, Carrier_t *crr)
 	    erts_aint_t old_val = new_val|ERTS_CRR_ALCTR_FLG_BUSY;
 
 	    ERTS_ALC_CPOOL_ASSERT(old_val
-				  == erts_smp_atomic_xchg_relb(&crr->allctr,
+				  == erts_atomic_xchg_relb(&crr->allctr,
 							       new_val));
 	}
 #else
-	erts_smp_atomic_set_relb(&crr->allctr, new_val);
+	erts_atomic_set_relb(&crr->allctr, new_val);
 #endif
     }
 }
 
-#endif /* ERTS_SMP */
 
 #if 0
 #define ERTS_DBG_CHK_FIX_LIST(A, FIX, IX, B)			\
@@ -1325,12 +1287,10 @@ chk_fix_list(Allctr_t *allctr, ErtsAlcFixList_t *fix, int ix, int before)
 
 static void *mbc_alloc(Allctr_t *allctr, Uint size);
 
-#ifdef ERTS_SMP
 typedef struct {
     ErtsAllctrDDBlock_t ddblock__; /* must be first */
     ErtsAlcType_t fix_type;
 } ErtsAllctrFixDDBlock_t;
-#endif
 
 #define ERTS_ALC_FIX_NO_UNUSE (((ErtsAlcType_t) 1) << ERTS_ALC_N_BITS)
 
@@ -1341,11 +1301,9 @@ dealloc_fix_block(Allctr_t *allctr,
 		  ErtsAlcFixList_t *fix,
 		  int dec_cc_on_redirect)
 {
-#ifdef ERTS_SMP
     /* May be redirected... */
     ASSERT((type & ERTS_ALC_FIX_NO_UNUSE) == 0);
     ((ErtsAllctrFixDDBlock_t *) ptr)->fix_type = type | ERTS_ALC_FIX_NO_UNUSE;
-#endif
     dealloc_block(allctr, ptr, fix, dec_cc_on_redirect);
 }
 
@@ -1379,12 +1337,10 @@ fix_cpool_check_shrink(Allctr_t *allctr,
 	    fix->u.cpool.shrink_list = 0;
 	else {
 	    void *p;
-#ifdef ERTS_SMP
 	    if (busy_pcrr_pp) {
 		clear_busy_pool_carrier(allctr, *busy_pcrr_pp);
 		*busy_pcrr_pp = NULL;
 	    }
-#endif
 	    fix->u.cpool.shrink_list--;
 	    p = fix->list;
 	    fix->list = *((void **) p);
@@ -1477,10 +1433,8 @@ fix_cpool_alloc_shrink(Allctr_t *allctr, erts_aint32_t flgs)
     int ix, o;
     int flush = flgs == 0;
 
-#ifdef USE_THREADS
     if (allctr->thread_safe)
 	erts_mtx_lock(&allctr->mutex);
-#endif
 
     for (ix = 0; ix < ERTS_ALC_NO_FIXED_SIZES; ix++) {
 	ErtsAlcFixList_t *fix = &allctr->fix[ix];
@@ -1520,10 +1474,8 @@ fix_cpool_alloc_shrink(Allctr_t *allctr, erts_aint32_t flgs)
     if (all_empty)
 	sched_fix_shrink(allctr, 0);
 
-#ifdef USE_THREADS
     if (allctr->thread_safe)
 	erts_mtx_unlock(&allctr->mutex);
-#endif
 
     return res;
 }
@@ -1635,10 +1587,8 @@ fix_nocpool_alloc_shrink(Allctr_t *allctr, erts_aint32_t flgs)
     int ix, o;
     int flush = flgs == 0;
 
-#ifdef USE_THREADS
     if (allctr->thread_safe)
 	erts_mtx_lock(&allctr->mutex);
-#endif
 
     for (ix = 0; ix < ERTS_ALC_NO_FIXED_SIZES; ix++) {
 	ErtsAlcFixList_t *fix = &allctr->fix[ix];
@@ -1680,10 +1630,8 @@ fix_nocpool_alloc_shrink(Allctr_t *allctr, erts_aint32_t flgs)
     if (all_empty)
 	sched_fix_shrink(allctr, 0);
 
-#ifdef USE_THREADS
     if (allctr->thread_safe)
 	erts_mtx_unlock(&allctr->mutex);
-#endif
 
     return res;
 }
@@ -1709,7 +1657,6 @@ dealloc_mbc(Allctr_t *allctr, Carrier_t *crr)
     dealloc_carrier(allctr, crr, 1);
 }
 
-#ifdef ERTS_SMP
 
 static ERTS_INLINE Allctr_t*
 get_pref_allctr(void *extra)
@@ -1750,7 +1697,7 @@ get_used_allctr(Allctr_t *pref_allctr, int pref_lock, void *p, UWord *sizep,
 	crr = BLK_TO_SBC(blk);
 	if (sizep)
 	    *sizep = SBC_BLK_SZ(blk) - ABLK_HDR_SZ;  
-	iallctr = erts_smp_atomic_read_dirty(&crr->allctr);
+	iallctr = erts_atomic_read_dirty(&crr->allctr);
     }
     else {
 	crr = ABLK_TO_MBC(blk);
@@ -1758,10 +1705,10 @@ get_used_allctr(Allctr_t *pref_allctr, int pref_lock, void *p, UWord *sizep,
 	if (sizep)
 	    *sizep = MBC_ABLK_SZ(blk) - ABLK_HDR_SZ;
 	if (!ERTS_ALC_IS_CPOOL_ENABLED(pref_allctr))
-	    iallctr = erts_smp_atomic_read_dirty(&crr->allctr);
+	    iallctr = erts_atomic_read_dirty(&crr->allctr);
 	else {
 	    int locked_pref_allctr = 0;
-	    iallctr = erts_smp_atomic_read_ddrb(&crr->allctr);
+	    iallctr = erts_atomic_read_ddrb(&crr->allctr);
 
 	    if (ERTS_ALC_TS_PREF_LOCK_IF_USED == pref_lock
 		&& pref_allctr->thread_safe) {
@@ -1777,7 +1724,7 @@ get_used_allctr(Allctr_t *pref_allctr, int pref_lock, void *p, UWord *sizep,
 		erts_aint_t act;
 
 		ERTS_ALC_CPOOL_ASSERT(!(iallctr & ERTS_CRR_ALCTR_FLG_BUSY));
-		act = erts_smp_atomic_cmpxchg_ddrb(&crr->allctr,
+		act = erts_atomic_cmpxchg_ddrb(&crr->allctr,
 						   iallctr|ERTS_CRR_ALCTR_FLG_BUSY,
 						   iallctr);
 		if (act == iallctr) {
@@ -2152,10 +2099,10 @@ handle_delayed_dealloc(Allctr_t *allctr,
 	    ERTS_ALC_CPOOL_ASSERT(ERTS_ALC_IS_CPOOL_ENABLED(allctr));
 	    ERTS_ALC_CPOOL_ASSERT(allctr == crr->cpool.orig_allctr);
 	    ERTS_ALC_CPOOL_ASSERT(((erts_aint_t) allctr)
-				  != (erts_smp_atomic_read_nob(&crr->allctr)
+				  != (erts_atomic_read_nob(&crr->allctr)
 				      & ~ERTS_CRR_ALCTR_FLG_MASK));
 
-	    erts_smp_atomic_set_nob(&crr->allctr, ((erts_aint_t) allctr));
+	    erts_atomic_set_nob(&crr->allctr, ((erts_aint_t) allctr));
 
 	    schedule_dealloc_carrier(allctr, crr);
 	}
@@ -2201,9 +2148,7 @@ enqueue_dealloc_other_instance(ErtsAlcType_t type,
 	erts_alloc_notify_delayed_dealloc(allctr->ix);
 }
 
-#endif
 
-#ifdef ERTS_SMP
 static void
 set_new_allctr_abandon_limit(Allctr_t *allctr);
 static void
@@ -2265,7 +2210,6 @@ erts_alcu_check_delayed_dealloc(Allctr_t *allctr,
 			   thr_prgr_p,
 			   more_work);
 }
-#endif
 
 #define ERTS_ALCU_HANDLE_DD_IN_OP(Allctr, Locked)			\
     handle_delayed_dealloc((Allctr), (Locked), 1, 			\
@@ -2276,24 +2220,18 @@ dealloc_block(Allctr_t *allctr, void *ptr, ErtsAlcFixList_t *fix, int dec_cc_on_
 {
     Block_t *blk = UMEM2BLK(ptr);
 
-    ERTS_SMP_LC_ASSERT(!allctr->thread_safe
+    ERTS_LC_ASSERT(!allctr->thread_safe
 		       || erts_lc_mtx_is_locked(&allctr->mutex));
 
     if (IS_SBC_BLK(blk)) {
 	destroy_carrier(allctr, blk, NULL);
-#ifdef ERTS_SMP
 	if (fix && ERTS_ALC_IS_CPOOL_ENABLED(allctr)) {
 	    ErtsAlcType_t type = ((ErtsAllctrFixDDBlock_t *) ptr)->fix_type;
 	    if (!(type & ERTS_ALC_FIX_NO_UNUSE))
 		fix->u.cpool.used--;
 	    fix->u.cpool.allocated--;
 	}
-#endif
     }
-#ifndef ERTS_SMP
-    else
-	mbc_free(allctr, ptr, NULL);
-#else
     else if (!ERTS_ALC_IS_CPOOL_ENABLED(allctr))
 	mbc_free(allctr, ptr, NULL);
     else {
@@ -2323,7 +2261,6 @@ dealloc_block(Allctr_t *allctr, void *ptr, ErtsAlcFixList_t *fix, int dec_cc_on_
 		erts_alloc_notify_delayed_dealloc(used_allctr->ix);
 	}
     }
-#endif
 }
 
 /* Multi block carrier alloc/realloc/free ... */
@@ -2571,9 +2508,7 @@ mbc_free(Allctr_t *allctr, void *p, Carrier_t **busy_pcrr_pp)
     else {
 	(*allctr->link_free_block)(allctr, blk);
 	HARD_CHECK_BLK_CARRIER(allctr, blk);
-#ifdef ERTS_SMP
 	check_abandon_carrier(allctr, blk, busy_pcrr_pp);
-#endif
     }
 }
 
@@ -2607,10 +2542,8 @@ mbc_realloc(Allctr_t *allctr, void *p, Uint size, Uint32 alcu_flgs,
 	return NULL;
 #else /* !MBC_REALLOC_ALWAYS_MOVES */
 
-#ifdef ERTS_SMP
     if (busy_pcrr_pp && *busy_pcrr_pp)
 	goto realloc_move; /* Don't want to use carrier in pool */
-#endif
 
     get_blk_sz = blk_sz = UMEMSZ2BLKSZ(allctr, size);
 
@@ -2731,9 +2664,7 @@ mbc_realloc(Allctr_t *allctr, void *p, Uint size, Uint32 alcu_flgs,
 		    
 	HARD_CHECK_BLK_CARRIER(allctr, blk);
 
-#ifdef ERTS_SMP
 	check_abandon_carrier(allctr, nxt_blk, NULL);
-#endif
 
 	return p;
     }
@@ -2845,9 +2776,7 @@ mbc_realloc(Allctr_t *allctr, void *p, Uint size, Uint32 alcu_flgs,
 
     if (cand_blk_sz < get_blk_sz) {
 	/* We wont fit in cand_blk get a new one */
-#ifdef ERTS_SMP
     realloc_move:
-#endif
 #endif /* !MBC_REALLOC_ALWAYS_MOVES */
 
 	new_p = mbc_alloc(allctr, size);
@@ -2949,7 +2878,6 @@ mbc_realloc(Allctr_t *allctr, void *p, Uint size, Uint32 alcu_flgs,
 #endif /* !MBC_REALLOC_ALWAYS_MOVES */
 }
 
-#ifdef ERTS_SMP
 
 #define ERTS_ALC_MAX_DEALLOC_CARRIER		10
 #define ERTS_ALC_CPOOL_MAX_FETCH_INSPECT	20
@@ -3120,7 +3048,7 @@ cpool_insert(Allctr_t *allctr, Carrier_t *crr)
 
     ERTS_ALC_CPOOL_ASSERT(allctr->alloc_no == ERTS_ALC_A_INVALID /* testcase */
 			  || erts_thr_progress_is_managed_thread());
-    ERTS_ALC_CPOOL_ASSERT(erts_smp_atomic_read_nob(&crr->allctr)
+    ERTS_ALC_CPOOL_ASSERT(erts_atomic_read_nob(&crr->allctr)
 			  == (erts_aint_t) allctr);
 
     erts_atomic_add_nob(&allctr->cpool.stat.blocks_size,
@@ -3190,7 +3118,7 @@ cpool_insert(Allctr_t *allctr, Carrier_t *crr)
 			 (erts_aint_t) &crr->cpool,
 			 (erts_aint_t) cpd1p);
 
-    erts_smp_atomic_set_wb(&crr->allctr,
+    erts_atomic_set_wb(&crr->allctr,
 			   ((erts_aint_t) allctr)|ERTS_CRR_ALCTR_FLG_IN_POOL);
     LTTNG3(carrier_pool_put, ERTS_ALC_A2AD(allctr->alloc_no), allctr->ix, CARRIER_SZ(crr));
 }
@@ -3322,11 +3250,11 @@ cpool_fetch(Allctr_t *allctr, UWord size)
 	ASSERT(!is_in_list(&allctr->cpool.traitor_list, dl));
 	ASSERT(crr->cpool.orig_allctr == allctr);
 	dl = dl->next;
-	exp = erts_smp_atomic_read_rb(&crr->allctr);
+	exp = erts_atomic_read_rb(&crr->allctr);
 	if ((exp & ERTS_CRR_ALCTR_FLG_MASK) == ERTS_CRR_ALCTR_FLG_IN_POOL
 	    && erts_atomic_read_nob(&crr->cpool.max_size) >= size) {
 	    /* Try to fetch it... */
-	    act = erts_smp_atomic_cmpxchg_mb(&crr->allctr,
+	    act = erts_atomic_cmpxchg_mb(&crr->allctr,
 					     (erts_aint_t) allctr,
 					     exp);
 	    if (act == exp) {
@@ -3368,12 +3296,12 @@ cpool_fetch(Allctr_t *allctr, UWord size)
 	ASSERT(dl != &allctr->cpool.pooled_list);
 	ASSERT(crr->cpool.orig_allctr == allctr);
 	dl = dl->next;
-	exp = erts_smp_atomic_read_rb(&crr->allctr);
+	exp = erts_atomic_read_rb(&crr->allctr);
 	if (exp & ERTS_CRR_ALCTR_FLG_IN_POOL) {
 	    if (!(exp & ERTS_CRR_ALCTR_FLG_BUSY)
 		&& erts_atomic_read_nob(&crr->cpool.max_size) >= size) {
 		/* Try to fetch it... */
-		act = erts_smp_atomic_cmpxchg_mb(&crr->allctr,
+		act = erts_atomic_cmpxchg_mb(&crr->allctr,
 						 (erts_aint_t) allctr,
 						 exp);
 		if (act == exp) {
@@ -3449,12 +3377,12 @@ cpool_fetch(Allctr_t *allctr, UWord size)
 	    has_passed_sentinel = 1;
 	}
 	crr = (Carrier_t *)(((char *)cpdp) - offsetof(Carrier_t, cpool));
-	exp = erts_smp_atomic_read_rb(&crr->allctr);
+	exp = erts_atomic_read_rb(&crr->allctr);
 	if (((exp & (ERTS_CRR_ALCTR_FLG_MASK)) == ERTS_CRR_ALCTR_FLG_IN_POOL)
 	    && (erts_atomic_read_nob(&cpdp->max_size) >= size)) {
 	    erts_aint_t act;
 	    /* Try to fetch it... */
-	    act = erts_smp_atomic_cmpxchg_mb(&crr->allctr,
+	    act = erts_atomic_cmpxchg_mb(&crr->allctr,
 					     (erts_aint_t) allctr,
 					     exp);
 	    if (act == exp) {
@@ -3477,11 +3405,11 @@ check_dc_list:
 	    Block_t* blk;
 	    unlink_carrier(&allctr->cpool.dc_list, crr);
 #ifdef ERTS_ALC_CPOOL_DEBUG
-	    ERTS_ALC_CPOOL_ASSERT(erts_smp_atomic_xchg_nob(&crr->allctr,
+	    ERTS_ALC_CPOOL_ASSERT(erts_atomic_xchg_nob(&crr->allctr,
 							   ((erts_aint_t) allctr))
 				  == (((erts_aint_t) allctr) & ~ERTS_CRR_ALCTR_FLG_MASK));
 #else
-	    erts_smp_atomic_set_nob(&crr->allctr, ((erts_aint_t) allctr));
+	    erts_atomic_set_nob(&crr->allctr, ((erts_aint_t) allctr));
 #endif
 	    blk = MBC_TO_FIRST_BLK(allctr, crr);
 	    ASSERT(FBLK_TO_MBC(blk) == crr);
@@ -3584,7 +3512,7 @@ schedule_dealloc_carrier(Allctr_t *allctr, Carrier_t *crr)
 	ERTS_ALC_CPOOL_ASSERT(crr == FBLK_TO_MBC(blk));
 	ERTS_ALC_CPOOL_ASSERT(crr == FIRST_BLK_TO_MBC(allctr, blk));
 	ERTS_ALC_CPOOL_ASSERT(((erts_aint_t) allctr)
-			      == (erts_smp_atomic_read_nob(&crr->allctr)
+			      == (erts_atomic_read_nob(&crr->allctr)
 				  & ~ERTS_CRR_ALCTR_FLG_MASK));
 
 	if (ddq_enqueue(&orig_allctr->dd.q, BLK2UMEM(blk), cinit))
@@ -3735,7 +3663,6 @@ cpool_read_stat(Allctr_t *allctr, UWord *nocp, UWord *cszp, UWord *nobp, UWord *
 }
 
 
-#endif /* ERTS_SMP */
 
 #ifdef DEBUG
 
@@ -3836,7 +3763,6 @@ create_carrier(Allctr_t *allctr, Uint umem_sz, UWord flags)
         blk_sz = UMEMSZ2BLKSZ(allctr, umem_sz);
     }
 
-#ifdef ERTS_SMP
     allctr->cpool.disable_abandon = ERTS_ALC_CPOOL_MAX_DISABLE_ABANDON;
 
     if ((flags & (CFLG_MBC|CFLG_NO_CPOOL)) == CFLG_MBC
@@ -3852,7 +3778,6 @@ create_carrier(Allctr_t *allctr, Uint umem_sz, UWord flags)
 	    return blk;
 	}
     }
-#endif
 
 #if HAVE_ERTS_MSEG
 
@@ -3982,9 +3907,7 @@ create_carrier(Allctr_t *allctr, Uint umem_sz, UWord flags)
 	    allctr->main_carrier = crr;
 	}
 
-#ifdef ERTS_SMP
 	cpool_init_carrier_data(allctr, crr);
-#endif
 
 	link_carrier(&allctr->mbc_list, crr);
 
@@ -4204,19 +4127,17 @@ destroy_carrier(Allctr_t *allctr, Block_t *blk, Carrier_t **busy_pcrr_pp)
 	}
 #endif
 
-#ifdef ERTS_SMP
 	if (busy_pcrr_pp && *busy_pcrr_pp) {
 	    ERTS_ALC_CPOOL_ASSERT(*busy_pcrr_pp == crr);
 	    *busy_pcrr_pp = NULL;
-	    ERTS_ALC_CPOOL_ASSERT(erts_smp_atomic_read_nob(&crr->allctr)
+	    ERTS_ALC_CPOOL_ASSERT(erts_atomic_read_nob(&crr->allctr)
 				  == (((erts_aint_t) allctr)
 				      | ERTS_CRR_ALCTR_FLG_IN_POOL
 				      | ERTS_CRR_ALCTR_FLG_BUSY));
-	    erts_smp_atomic_set_nob(&crr->allctr, ((erts_aint_t) allctr));
+	    erts_atomic_set_nob(&crr->allctr, ((erts_aint_t) allctr));
 	    cpool_delete(allctr, allctr, crr);
 	}
 	else
-#endif
 	{
 	    unlink_carrier(&allctr->mbc_list, crr);
 #if HAVE_ERTS_MSEG
@@ -4247,11 +4168,7 @@ destroy_carrier(Allctr_t *allctr, Block_t *blk, Carrier_t **busy_pcrr_pp)
         }
 #endif
 
-#ifdef ERTS_SMP
 	schedule_dealloc_carrier(allctr, crr);
-#else
-	dealloc_mbc(allctr, crr);
-#endif
     }
 }
 
@@ -4294,9 +4211,7 @@ static struct {
     Eterm fix_types;
 
     Eterm mbcs;
-#ifdef ERTS_SMP
     Eterm mbcs_pool;
-#endif
     Eterm sbcs;
 
     Eterm sys_alloc_carriers_size;
@@ -4384,9 +4299,7 @@ init_atoms(Allctr_t *allctr)
 	AM_INIT(fix_types);
 
 	AM_INIT(mbcs);
-#ifdef ERTS_SMP
 	AM_INIT(mbcs_pool);
-#endif
 	AM_INIT(sbcs);
 
 	AM_INIT(sys_alloc_carriers_size);
@@ -4636,7 +4549,6 @@ sz_info_carriers(Allctr_t *allctr,
     return res;
 }
 
-#ifdef ERTS_SMP
 
 static Eterm
 info_cpool(Allctr_t *allctr,
@@ -4690,7 +4602,6 @@ info_cpool(Allctr_t *allctr,
     return res;
 }
 
-#endif /* ERTS_SMP */
 
 static Eterm
 info_carriers(Allctr_t *allctr,
@@ -4945,11 +4856,7 @@ info_options(Allctr_t *allctr,
 	return res;
     }
 
-#ifdef ERTS_SMP
     acul = allctr->cpool.util_limit;
-#else
-    acul = 0;
-#endif
 
     if (print_to_p) {
 	char topt[21]; /* Enough for any 64-bit integer */
@@ -5132,19 +5039,15 @@ erts_alcu_info_options(Allctr_t *allctr,
     if (hpp || szp)
 	ensure_atoms_initialized(allctr);
 
-#ifdef USE_THREADS
     if (allctr->thread_safe) {
 	erts_allctr_wrapper_pre_lock();
 	erts_mtx_lock(&allctr->mutex);
     }
-#endif
     res = info_options(allctr, print_to_p, print_to_arg, hpp, szp);
-#ifdef USE_THREADS
     if (allctr->thread_safe) { 
 	erts_mtx_unlock(&allctr->mutex);
 	erts_allctr_wrapper_pre_unlock();
     }
-#endif
     return res;
 }
 
@@ -5160,9 +5063,7 @@ erts_alcu_sz_info(Allctr_t *allctr,
 		  Uint *szp)
 {
     Eterm res, mbcs, sbcs, fix = THE_NON_VALUE;
-#ifdef ERTS_SMP
     Eterm mbcs_pool;
-#endif
 
     res  = THE_NON_VALUE;
 
@@ -5177,12 +5078,10 @@ erts_alcu_sz_info(Allctr_t *allctr,
     if (hpp || szp)
 	ensure_atoms_initialized(allctr);
 
-#ifdef USE_THREADS
     if (allctr->thread_safe) {
 	erts_allctr_wrapper_pre_lock();
 	erts_mtx_lock(&allctr->mutex);
     }
-#endif
 
     ERTS_ALCU_DBG_CHK_THR_ACCESS(allctr);
 
@@ -5198,23 +5097,19 @@ erts_alcu_sz_info(Allctr_t *allctr,
 	fix = sz_info_fix(allctr, internal, print_to_p, print_to_arg, hpp, szp);
     mbcs = sz_info_carriers(allctr, &allctr->mbcs, "mbcs ", print_to_p,
 			    print_to_arg, hpp, szp);
-#ifdef ERTS_SMP
     if (ERTS_ALC_IS_CPOOL_ENABLED(allctr))
 	mbcs_pool = info_cpool(allctr, 1, "mbcs_pool ", print_to_p,
 			       print_to_arg, hpp, szp);
     else
 	mbcs_pool = THE_NON_VALUE; /* shut up annoying warning... */
-#endif
     sbcs = sz_info_carriers(allctr, &allctr->sbcs, "sbcs ", print_to_p,
 			    print_to_arg, hpp, szp);
 
     if (hpp || szp) {
 	res = NIL;
 	add_2tup(hpp, szp, &res, am.sbcs, sbcs);
-#ifdef ERTS_SMP
 	if (ERTS_ALC_IS_CPOOL_ENABLED(allctr))
 	    add_2tup(hpp, szp, &res, am.mbcs_pool, mbcs_pool);
-#endif
 	add_2tup(hpp, szp, &res, am.mbcs, mbcs);
 	add_fix_types(allctr, internal, hpp, szp, &res, fix);
     }
@@ -5225,12 +5120,10 @@ erts_alcu_sz_info(Allctr_t *allctr,
     }
 
 
-#ifdef USE_THREADS
     if (allctr->thread_safe) {
 	erts_mtx_unlock(&allctr->mutex);
 	erts_allctr_wrapper_pre_unlock();
     }
-#endif
 
     return res;
 }
@@ -5246,9 +5139,7 @@ erts_alcu_info(Allctr_t *allctr,
 	       Uint *szp)
 {
     Eterm res, sett, mbcs, sbcs, calls, fix = THE_NON_VALUE;
-#ifdef ERTS_SMP
     Eterm mbcs_pool;
-#endif
 
     res  = THE_NON_VALUE;
 
@@ -5263,12 +5154,10 @@ erts_alcu_info(Allctr_t *allctr,
     if (hpp || szp)
 	ensure_atoms_initialized(allctr);
 
-#ifdef USE_THREADS
     if (allctr->thread_safe) {
 	erts_allctr_wrapper_pre_lock();
 	erts_mtx_lock(&allctr->mutex);
     }
-#endif
 
     ERTS_ALCU_DBG_CHK_THR_ACCESS(allctr);
 
@@ -5293,13 +5182,11 @@ erts_alcu_info(Allctr_t *allctr,
 	fix = sz_info_fix(allctr, internal, print_to_p, print_to_arg, hpp, szp);
     mbcs = info_carriers(allctr, &allctr->mbcs, "mbcs ", print_to_p,
 			 print_to_arg, hpp, szp);
-#ifdef ERTS_SMP
     if (ERTS_ALC_IS_CPOOL_ENABLED(allctr))
 	mbcs_pool = info_cpool(allctr, 0, "mbcs_pool ", print_to_p,
 			       print_to_arg, hpp, szp);
     else
 	mbcs_pool = THE_NON_VALUE; /* shut up annoying warning... */
-#endif
     sbcs = info_carriers(allctr, &allctr->sbcs, "sbcs ", print_to_p,
 			 print_to_arg, hpp, szp);
     calls = info_calls(allctr, print_to_p, print_to_arg, hpp, szp);
@@ -5309,10 +5196,8 @@ erts_alcu_info(Allctr_t *allctr,
 
 	add_2tup(hpp, szp, &res, am.calls, calls);
 	add_2tup(hpp, szp, &res, am.sbcs, sbcs);
-#ifdef ERTS_SMP
 	if (ERTS_ALC_IS_CPOOL_ENABLED(allctr))
 	    add_2tup(hpp, szp, &res, am.mbcs_pool, mbcs_pool);
-#endif
 	add_2tup(hpp, szp, &res, am.mbcs, mbcs);
 	add_fix_types(allctr, internal, hpp, szp, &res, fix);
 	add_2tup(hpp, szp, &res, am.options, sett);
@@ -5328,12 +5213,10 @@ erts_alcu_info(Allctr_t *allctr,
     }
 
 
-#ifdef USE_THREADS
     if (allctr->thread_safe) {
 	erts_mtx_unlock(&allctr->mutex);
 	erts_allctr_wrapper_pre_unlock();
     }
-#endif
 
     return res;
 }
@@ -5343,10 +5226,8 @@ void
 erts_alcu_current_size(Allctr_t *allctr, AllctrSize_t *size, ErtsAlcUFixInfo_t *fi, int fisz)
 {
 
-#ifdef USE_THREADS
     if (allctr->thread_safe)
 	erts_mtx_lock(&allctr->mutex);
-#endif
 
     size->carriers = allctr->mbcs.curr.norm.mseg.size;
     size->carriers += allctr->mbcs.curr.norm.sys_alloc.size;
@@ -5356,14 +5237,12 @@ erts_alcu_current_size(Allctr_t *allctr, AllctrSize_t *size, ErtsAlcUFixInfo_t *
     size->blocks = allctr->mbcs.blocks.curr.size;
     size->blocks += allctr->sbcs.blocks.curr.size;
 
-#ifdef ERTS_SMP
     if (ERTS_ALC_IS_CPOOL_ENABLED(allctr)) {
 	UWord csz, bsz;
 	cpool_read_stat(allctr, NULL, &csz, NULL, &bsz);
 	size->blocks += bsz;
 	size->carriers += csz;
     }
-#endif
 
     if (fi) {
 	int ix;
@@ -5385,10 +5264,8 @@ erts_alcu_current_size(Allctr_t *allctr, AllctrSize_t *size, ErtsAlcUFixInfo_t *
 	}
     }
 
-#ifdef USE_THREADS
     if (allctr->thread_safe)
 	erts_mtx_unlock(&allctr->mutex);
-#endif
 }
 
 /* ----------------------------------------------------------------------- */
@@ -5403,7 +5280,7 @@ do_erts_alcu_alloc(ErtsAlcType_t type, void *extra, Uint size)
 
     ASSERT(allctr);
 
-    ERTS_SMP_LC_ASSERT(!allctr->thread_safe
+    ERTS_LC_ASSERT(!allctr->thread_safe
 		       || erts_lc_mtx_is_locked(&allctr->mutex));
 
     ERTS_ALCU_DBG_CHK_THR_ACCESS(allctr);
@@ -5436,18 +5313,13 @@ do_erts_alcu_alloc(ErtsAlcType_t type, void *extra, Uint size)
 void *erts_alcu_alloc(ErtsAlcType_t type, void *extra, Uint size)
 {
     void *res;
-#ifdef ERTS_SMP
     ASSERT(!"This is not thread safe");
-#elif defined(USE_THREADS)
-    ASSERT(erts_equal_tids(erts_main_thread, erts_thr_self()));
-#endif
     res = do_erts_alcu_alloc(type, extra, size);
     DEBUG_CHECK_ALIGNMENT(res);
     return res;
 }
 
 
-#ifdef USE_THREADS
 
 void *
 erts_alcu_alloc_ts(ErtsAlcType_t type, void *extra, Uint size)
@@ -5463,7 +5335,6 @@ erts_alcu_alloc_ts(ErtsAlcType_t type, void *extra, Uint size)
     return res;
 }
 
-#ifdef ERTS_SMP
 
 void *
 erts_alcu_alloc_thr_spec(ErtsAlcType_t type, void *extra, Uint size)
@@ -5503,21 +5374,17 @@ erts_alcu_alloc_thr_pref(ErtsAlcType_t type, void *extra, Uint size)
     if (pref_allctr->thread_safe)
 	erts_mtx_lock(&pref_allctr->mutex);
 
-#ifdef ERTS_SMP
     ASSERT(pref_allctr->dd.use);
     ERTS_ALCU_HANDLE_DD_IN_OP(pref_allctr, 1);
-#endif
 
     ERTS_ALCU_DBG_CHK_THR_ACCESS(pref_allctr);
 
     res = do_erts_alcu_alloc(type, pref_allctr, size);
 
-#ifdef ERTS_SMP
     if (!res && ERTS_ALCU_HANDLE_DD_IN_OP(pref_allctr, 1)) {
 	/* Cleaned up a bit more; try one more time... */
 	res = do_erts_alcu_alloc(type, pref_allctr, size);
     }
-#endif
 
     if (pref_allctr->thread_safe)
 	erts_mtx_unlock(&pref_allctr->mutex);
@@ -5528,9 +5395,7 @@ erts_alcu_alloc_thr_pref(ErtsAlcType_t type, void *extra, Uint size)
     return res;
 }
 
-#endif
 
-#endif
 
 /* ------------------------------------------------------------------------- */
 
@@ -5543,7 +5408,7 @@ do_erts_alcu_free(ErtsAlcType_t type, void *extra, void *p,
 
     ASSERT(allctr);
 
-    ERTS_SMP_LC_ASSERT(!allctr->thread_safe
+    ERTS_LC_ASSERT(!allctr->thread_safe
 		       || erts_lc_mtx_is_locked(&allctr->mutex));
 
     ERTS_ALCU_DBG_CHK_THR_ACCESS(allctr);
@@ -5573,7 +5438,6 @@ void erts_alcu_free(ErtsAlcType_t type, void *extra, void *p)
     do_erts_alcu_free(type, extra, p, NULL);
 }
 
-#ifdef USE_THREADS
 
 void
 erts_alcu_free_ts(ErtsAlcType_t type, void *extra, void *p)
@@ -5584,7 +5448,6 @@ erts_alcu_free_ts(ErtsAlcType_t type, void *extra, void *p)
     erts_mtx_unlock(&allctr->mutex);
 }
 
-#ifdef ERTS_SMP
 
 void
 erts_alcu_free_thr_spec(ErtsAlcType_t type, void *extra, void *p)
@@ -5634,9 +5497,7 @@ erts_alcu_free_thr_pref(ErtsAlcType_t type, void *extra, void *p)
     }
 }
 
-#endif
 
-#endif
 
 /* ------------------------------------------------------------------------- */
 
@@ -5656,7 +5517,7 @@ do_erts_alcu_realloc(ErtsAlcType_t type,
 
     ASSERT(allctr);
 
-    ERTS_SMP_LC_ASSERT(!allctr->thread_safe
+    ERTS_LC_ASSERT(!allctr->thread_safe
 		       || erts_lc_mtx_is_locked(&allctr->mutex));
 
     ERTS_ALCU_DBG_CHK_THR_ACCESS(allctr);
@@ -5785,7 +5646,6 @@ erts_alcu_realloc_mv(ErtsAlcType_t type, void *extra, void *p, Uint size)
 }
 
 
-#ifdef USE_THREADS
 
 void *
 erts_alcu_realloc_ts(ErtsAlcType_t type, void *extra, void *ptr, Uint size)
@@ -5824,7 +5684,6 @@ erts_alcu_realloc_mv_ts(ErtsAlcType_t type, void *extra, void *p, Uint size)
     return res;
 }
 
-#ifdef ERTS_SMP
 
 void *
 erts_alcu_realloc_thr_spec(ErtsAlcType_t type, void *extra,
@@ -5905,9 +5764,7 @@ realloc_thr_pref(ErtsAlcType_t type, void *extra, void *p, Uint size,
     Allctr_t *pref_allctr, *used_allctr;
     UWord old_user_size;
     Carrier_t *busy_pcrr_p;
-#ifdef ERTS_SMP
     int retried;
-#endif
 
     if (!p)
 	return erts_alcu_alloc_thr_pref(type, extra, size);
@@ -5917,12 +5774,10 @@ realloc_thr_pref(ErtsAlcType_t type, void *extra, void *p, Uint size,
     if (pref_allctr->thread_safe)
 	erts_mtx_lock(&pref_allctr->mutex);
 
-#ifdef ERTS_SMP
     ASSERT(pref_allctr->dd.use);
     ERTS_ALCU_HANDLE_DD_IN_OP(pref_allctr, 1);
     retried = 0;
 restart:
-#endif
 
     used_allctr = get_used_allctr(pref_allctr, ERTS_ALC_TS_PREF_LOCK_NO,
 				  p, &old_user_size, &busy_pcrr_p);
@@ -5938,13 +5793,11 @@ restart:
 				   0,
 				   &busy_pcrr_p);
 	clear_busy_pool_carrier(used_allctr, busy_pcrr_p);
-#ifdef ERTS_SMP
 	if (!res && !retried && ERTS_ALCU_HANDLE_DD_IN_OP(pref_allctr, 1)) {
 	    /* Cleaned up a bit more; try one more time... */
 	    retried = 1;
 	    goto restart;
 	}
-#endif	    
 	if (pref_allctr->thread_safe)
 	    erts_mtx_unlock(&pref_allctr->mutex);
     }
@@ -5999,9 +5852,7 @@ erts_alcu_realloc_mv_thr_pref(ErtsAlcType_t type, void *extra,
     return realloc_thr_pref(type, extra, p, size, 1);
 }
 
-#endif
 
-#endif
 
 /* ------------------------------------------------------------------------- */
 
@@ -6022,10 +5873,8 @@ erts_alcu_start(Allctr_t *allctr, AllctrInit_t *init)
     sys_memcpy((void *) &allctr->mseg_opt,
 	       (void *) &erts_mseg_default_opt,
 	       sizeof(ErtsMsegOpt_t));
-#ifdef ERTS_SMP
     if (init->tspec || init->tpref)
 	allctr->mseg_opt.sched_spec = 1;
-#endif /* ERTS_SMP */
 #endif /* HAVE_ERTS_MSEG */
 
     allctr->name_prefix			= init->name_prefix;
@@ -6083,7 +5932,6 @@ erts_alcu_start(Allctr_t *allctr, AllctrInit_t *init)
 	goto error;
     allctr->min_block_size		= UNIT_CEILING(allctr->min_block_size
 						       + sizeof(FreeBlkFtr_t));
-#ifdef ERTS_SMP
     if (init->tpref) {
 	Uint sz = ABLK_HDR_SZ;
 	sz += (init->fix ? 
@@ -6107,7 +5955,6 @@ erts_alcu_start(Allctr_t *allctr, AllctrInit_t *init)
     erts_atomic_init_nob(&allctr->cpool.stat.no_carriers, 0);
     allctr->cpool.check_limit_count = ERTS_ALC_CPOOL_CHECK_LIMIT_COUNT;
     allctr->cpool.util_limit = init->ts ? 0 : init->acul;
-#endif
 
     allctr->sbc_threshold		= init->sbct;
 #ifndef ARCH_64
@@ -6131,7 +5978,6 @@ erts_alcu_start(Allctr_t *allctr, AllctrInit_t *init)
 	allctr->mseg_opt.abs_shrink_th = ~((UWord) 0) / 100;
 #endif
 
-#ifdef USE_THREADS
     if (init->ts) {
 	allctr->thread_safe = 1;
 
@@ -6142,7 +5988,6 @@ erts_alcu_start(Allctr_t *allctr, AllctrInit_t *init)
 	allctr->debug.saved_tid = 0;
 #endif
     }
-#endif
 
     if(!allctr->get_free_block
        || !allctr->link_free_block
@@ -6155,14 +6000,12 @@ erts_alcu_start(Allctr_t *allctr, AllctrInit_t *init)
 
     if (allctr->mbc_header_size < sizeof(Carrier_t))
 	goto error;
-#ifdef ERTS_SMP
     allctr->dd.use = 0;
     if (init->tpref) {
 	allctr->dd.use = 1;
 	init_dd_queue(&allctr->dd.q);
 	allctr->dd.ix = init->ix;
     }
-#endif
     allctr->mbc_header_size = (UNIT_CEILING(allctr->mbc_header_size
 					    + ABLK_HDR_SZ)
 			       - ABLK_HDR_SZ);
@@ -6216,10 +6059,8 @@ erts_alcu_start(Allctr_t *allctr, AllctrInit_t *init)
 			     | CFLG_NO_CPOOL
 			     | CFLG_MAIN_CARRIER);
 	if (!blk) {
-#ifdef USE_THREADS
 	  if (allctr->thread_safe)
 	    erts_mtx_destroy(&allctr->mutex);
-#endif
 	  erts_exit(ERTS_ABORT_EXIT,
 	    "Failed to create main carrier for %salloc\n",
 	    init->name_prefix);
@@ -6239,9 +6080,7 @@ erts_alcu_start(Allctr_t *allctr, AllctrInit_t *init)
 	    allctr->fix[i].type_size = init->fix_type_size[i];
 	    allctr->fix[i].list_size = 0;
 	    allctr->fix[i].list = NULL;
-#ifdef ERTS_SMP
 	    ASSERT(allctr->fix[i].type_size >= sizeof(ErtsAllctrFixDDBlock_t));
-#endif
 	    if (ERTS_ALC_IS_CPOOL_ENABLED(allctr)) {
 		allctr->fix[i].u.cpool.min_list_size = 0;
 		allctr->fix[i].u.cpool.shrink_list = 0;
@@ -6261,10 +6100,8 @@ erts_alcu_start(Allctr_t *allctr, AllctrInit_t *init)
 
  error:
 
-#ifdef USE_THREADS
     if (allctr->thread_safe)
 	erts_mtx_destroy(&allctr->mutex);
-#endif
 
     return 0;
 
@@ -6282,10 +6119,8 @@ erts_alcu_stop(Allctr_t *allctr)
     while (allctr->mbc_list.first)
 	destroy_carrier(allctr, MBC_TO_FIRST_BLK(allctr, allctr->mbc_list.first), NULL);
 
-#ifdef USE_THREADS
     if (allctr->thread_safe)
 	erts_mtx_destroy(&allctr->mutex);
-#endif
 
 }
 
@@ -6294,14 +6129,12 @@ erts_alcu_stop(Allctr_t *allctr)
 void
 erts_alcu_init(AlcUInit_t *init)
 {
-#ifdef ERTS_SMP
     int i;
     for (i = 0; i <= ERTS_ALC_A_MAX; i++) {
 	ErtsAlcCPoolData_t *sentinel = &carrier_pool[i].sentinel;
 	erts_atomic_init_nob(&sentinel->next, (erts_aint_t) sentinel);
 	erts_atomic_init_nob(&sentinel->prev, (erts_aint_t) sentinel);
     }
-#endif
     ERTS_CT_ASSERT(SBC_BLK_SZ_MASK == MBC_FBLK_SZ_MASK); /* see BLK_SZ */
 #if HAVE_ERTS_MSEG
     ASSERT(erts_mseg_unit_size() == ERTS_SACRR_UNIT_SZ);
@@ -6369,7 +6202,6 @@ erts_alcu_test(UWord op, UWord a1, UWord a2)
     case 0x01c: return (UWord) BLK_TO_MBC((Block_t*) a1);
     case 0x01d: ((Allctr_t*) a1)->add_mbc((Allctr_t*)a1, (Carrier_t*)a2); break;
     case 0x01e: ((Allctr_t*) a1)->remove_mbc((Allctr_t*)a1, (Carrier_t*)a2); break;
-#ifdef ERTS_SMP
     case 0x01f: return (UWord) sizeof(ErtsAlcCrrPool_t);
     case 0x020:
 	SET_CARRIER_HDR((Carrier_t *) a2, 0, SCH_SYS_ALLOC|SCH_MBC, (Allctr_t *) a1);
@@ -6383,14 +6215,6 @@ erts_alcu_test(UWord op, UWord a1, UWord a2)
 	return (UWord) a2;
     case 0x023: return (UWord) cpool_is_empty((Allctr_t *) a1);
     case 0x024: return (UWord) cpool_dbg_is_in_pool((Allctr_t *) a1, (Carrier_t *) a2);
-#else
-    case 0x01f: return (UWord) 0;
-    case 0x020: return (UWord) 0;
-    case 0x021: return (UWord) 0;
-    case 0x022: return (UWord) 0;
-    case 0x023: return (UWord) 0;
-    case 0x024: return (UWord) 0;
-#endif
     case 0x025: /* UMEM2BLK_TEST*/
 #ifdef DEBUG
 # ifdef HARD_DEBUG
@@ -6448,13 +6272,9 @@ erts_alcu_verify_unused(Allctr_t *allctr)
 void
 erts_alcu_verify_unused_ts(Allctr_t *allctr)
 {
-#ifdef USE_THREADS
     erts_mtx_lock(&allctr->mutex);
-#endif
     erts_alcu_verify_unused(allctr);
-#ifdef USE_THREADS
     erts_mtx_unlock(&allctr->mutex);
-#endif
 }
 
 #ifdef DEBUG
diff --git a/erts/emulator/beam/erl_alloc_util.h b/erts/emulator/beam/erl_alloc_util.h
index aa13cda9fb..faeb5ef368 100644
--- a/erts/emulator/beam/erl_alloc_util.h
+++ b/erts/emulator/beam/erl_alloc_util.h
@@ -24,10 +24,8 @@
 #define ERTS_ALCU_VSN_STR "3.0"
 
 #include "erl_alloc_types.h"
-#ifdef USE_THREADS
 #define ERL_THREADS_EMU_INTERNAL__
 #include "erl_threads.h"
-#endif
 
 #include "erl_mseg.h"
 #include "lttng-wrapper.h"
@@ -162,12 +160,10 @@ void *	erts_alcu_alloc(ErtsAlcType_t, void *, Uint);
 void *	erts_alcu_realloc(ErtsAlcType_t, void *, void *, Uint);
 void *	erts_alcu_realloc_mv(ErtsAlcType_t, void *, void *, Uint);
 void	erts_alcu_free(ErtsAlcType_t, void *, void *);
-#ifdef USE_THREADS
 void *	erts_alcu_alloc_ts(ErtsAlcType_t, void *, Uint);
 void *	erts_alcu_realloc_ts(ErtsAlcType_t, void *, void *, Uint);
 void *	erts_alcu_realloc_mv_ts(ErtsAlcType_t, void *, void *, Uint);
 void	erts_alcu_free_ts(ErtsAlcType_t, void *, void *);
-#ifdef ERTS_SMP
 void *	erts_alcu_alloc_thr_spec(ErtsAlcType_t, void *, Uint);
 void *	erts_alcu_realloc_thr_spec(ErtsAlcType_t, void *, void *, Uint);
 void *	erts_alcu_realloc_mv_thr_spec(ErtsAlcType_t, void *, void *, Uint);
@@ -176,8 +172,6 @@ void *	erts_alcu_alloc_thr_pref(ErtsAlcType_t, void *, Uint);
 void *	erts_alcu_realloc_thr_pref(ErtsAlcType_t, void *, void *, Uint);
 void *	erts_alcu_realloc_mv_thr_pref(ErtsAlcType_t, void *, void *, Uint);
 void	erts_alcu_free_thr_pref(ErtsAlcType_t, void *, void *);
-#endif
-#endif
 Eterm	erts_alcu_au_info_options(fmtfn_t *, void *, Uint **, Uint *);
 Eterm	erts_alcu_info_options(Allctr_t *, fmtfn_t *, void *, Uint **, Uint *);
 Eterm	erts_alcu_sz_info(Allctr_t *, int, int, fmtfn_t *, void *, Uint **, Uint *);
@@ -185,9 +179,7 @@ Eterm	erts_alcu_info(Allctr_t *, int, int, fmtfn_t *, void *, Uint **, Uint *);
 void	erts_alcu_init(AlcUInit_t *);
 void    erts_alcu_current_size(Allctr_t *, AllctrSize_t *,
 			       ErtsAlcUFixInfo_t *, int);
-#ifdef ERTS_SMP
 void    erts_alcu_check_delayed_dealloc(Allctr_t *, int, int *, ErtsThrPrgrVal *, int *);
-#endif
 erts_aint32_t erts_alcu_fix_alloc_shrink(Allctr_t *, erts_aint32_t);
 
 #ifdef ARCH_32
@@ -304,7 +296,6 @@ void erts_lcnt_update_allocator_locks(int enable);
 
 typedef union {char c[ERTS_ALLOC_ALIGN_BYTES]; long l; double d;} Unit_t;
 
-#ifdef ERTS_SMP
 
 typedef struct ErtsDoubleLink_t_ {
     struct ErtsDoubleLink_t_ *next;
@@ -323,21 +314,18 @@ typedef struct {
     ErtsDoubleLink_t abandoned; /* node in pooled_list or traitor_list */
 } ErtsAlcCPoolData_t;
 
-#endif
 
 typedef struct Carrier_t_ Carrier_t;
 struct Carrier_t_ {
     UWord chdr;
     Carrier_t *next;
     Carrier_t *prev;
-    erts_smp_atomic_t allctr;
-#ifdef ERTS_SMP
+    erts_atomic_t allctr;
     ErtsAlcCPoolData_t cpool; /* Overwritten by block if sbc */
-#endif
 };
 
 #define ERTS_ALC_CARRIER_TO_ALLCTR(C) \
-  ((Allctr_t *) (erts_smp_atomic_read_nob(&(C)->allctr) & ~FLG_MASK))
+  ((Allctr_t *) (erts_atomic_read_nob(&(C)->allctr) & ~FLG_MASK))
 
 typedef struct {
     Carrier_t *first;
@@ -430,7 +418,6 @@ typedef struct {
     } while (0)
 #endif
 
-#ifdef ERTS_SMP
 
 typedef union ErtsAllctrDDBlock_t_ ErtsAllctrDDBlock_t;
 
@@ -473,7 +460,6 @@ typedef struct {
     } head;
 } ErtsAllctrDDQueue_t;
 
-#endif
 
 typedef struct {
     size_t type_size;
@@ -496,7 +482,6 @@ typedef struct {
 } ErtsAlcFixList_t;
 
 struct Allctr_t_ {
-#ifdef ERTS_SMP
     struct {
 	/*
 	 * We want the queue at the beginning of
@@ -507,7 +492,6 @@ struct Allctr_t_ {
 	int		use;
 	int		ix;
     } dd;
-#endif
 
     /* Allocator name prefix */
     char *		name_prefix;
@@ -556,7 +540,6 @@ struct Allctr_t_ {
     /* Carriers */
     CarrierList_t	mbc_list;
     CarrierList_t	sbc_list;
-#ifdef ERTS_SMP
     struct {
 	/* pooled_list, traitor list and dc_list contain only
            carriers _created_ by this allocator */
@@ -575,7 +558,6 @@ struct Allctr_t_ {
 	    erts_atomic_t	no_carriers;
 	} stat;
     } cpool;
-#endif
 
     /* Main carrier (if there is one) */
     Carrier_t *		main_carrier;
@@ -618,7 +600,6 @@ struct Allctr_t_ {
     int			fix_shrink_scheduled;
     ErtsAlcFixList_t	*fix;
 
-#ifdef USE_THREADS
     /* Mutex for this allocator */
     erts_mtx_t		mutex;
     int			thread_safe;
@@ -627,7 +608,6 @@ struct Allctr_t_ {
 	Allctr_t	*next;
     } ts_list;
 
-#endif
 
     int			atoms_initialized;
 
@@ -650,13 +630,11 @@ struct Allctr_t_ {
     CarriersStats_t	mbcs;
     
 #ifdef DEBUG
-#ifdef USE_THREADS
     struct {
 	int saved_tid;
 	erts_tid_t tid;
     } debug;
 #endif
-#endif
 };
 
 int	erts_alcu_start(Allctr_t *, AllctrInit_t *);
diff --git a/erts/emulator/beam/erl_arith.c b/erts/emulator/beam/erl_arith.c
index 861532f241..b6625db0d3 100644
--- a/erts/emulator/beam/erl_arith.c
+++ b/erts/emulator/beam/erl_arith.c
@@ -114,7 +114,7 @@ BIF_RETTYPE intdiv_2(BIF_ALIST_2)
     }
     if (is_both_small(BIF_ARG_1,BIF_ARG_2)){
 	Sint ires = signed_val(BIF_ARG_1) / signed_val(BIF_ARG_2);
-	if (MY_IS_SSMALL(ires))
+	if (IS_SSMALL(ires))
 	    BIF_RET(make_small(ires));
     } 
     BIF_RET(erts_int_div(BIF_P, BIF_ARG_1, BIF_ARG_2));
@@ -276,8 +276,12 @@ shift(Process* p, Eterm arg1, Eterm arg2, int right)
 		goto do_bsl;
 	    } else if (is_small(arg1) || is_big(arg1)) {
 		/*
-		 * N bsl PositiveBigNum is too large to represent.
+		 * N bsl PositiveBigNum is too large to represent,
+                 * unless N is 0.
 		 */
+                if (arg1 == make_small(0)) {
+                    BIF_RET(arg1);
+                }
 		BIF_ERROR(p, SYSTEM_LIMIT);
 	    }
 	     /* Fall through if the left argument is not an integer. */
@@ -336,8 +340,7 @@ erts_mixed_plus(Process* p, Eterm arg1, Eterm arg2)
 		switch ((arg2 & _TAG_IMMED1_MASK) >> _TAG_PRIMARY_SIZE) {
 		case (_TAG_IMMED1_SMALL >> _TAG_PRIMARY_SIZE):
 		    ires = signed_val(arg1) + signed_val(arg2);
-		    ASSERT(MY_IS_SSMALL(ires) == IS_SSMALL(ires));
-		    if (MY_IS_SSMALL(ires)) {
+		    if (IS_SSMALL(ires)) {
 			return make_small(ires);
 		    } else {
 			hp = HAlloc(p, 2);
@@ -482,8 +485,7 @@ erts_mixed_minus(Process* p, Eterm arg1, Eterm arg2)
 		switch ((arg2 & _TAG_IMMED1_MASK) >> _TAG_PRIMARY_SIZE) {
 		case (_TAG_IMMED1_SMALL >> _TAG_PRIMARY_SIZE):
 		    ires = signed_val(arg1) - signed_val(arg2);
-		    ASSERT(MY_IS_SSMALL(ires) == IS_SSMALL(ires));
-		    if (MY_IS_SSMALL(ires)) {
+		    if (IS_SSMALL(ires)) {
 			return make_small(ires);
 		    } else {
 			hp = HAlloc(p, 2);
@@ -1177,8 +1179,7 @@ erts_gc_mixed_plus(Process* p, Eterm* reg, Uint live)
 		switch ((arg2 & _TAG_IMMED1_MASK) >> _TAG_PRIMARY_SIZE) {
 		case (_TAG_IMMED1_SMALL >> _TAG_PRIMARY_SIZE):
 		    ires = signed_val(arg1) + signed_val(arg2);
-		    ASSERT(MY_IS_SSMALL(ires) == IS_SSMALL(ires));
-		    if (MY_IS_SSMALL(ires)) {
+		    if (IS_SSMALL(ires)) {
 			return make_small(ires);
 		    } else {
 			if (ERTS_NEED_GC(p, 2)) {
@@ -1345,8 +1346,7 @@ erts_gc_mixed_minus(Process* p, Eterm* reg, Uint live)
 		switch ((arg2 & _TAG_IMMED1_MASK) >> _TAG_PRIMARY_SIZE) {
 		case (_TAG_IMMED1_SMALL >> _TAG_PRIMARY_SIZE):
 		    ires = signed_val(arg1) - signed_val(arg2);
-		    ASSERT(MY_IS_SSMALL(ires) == IS_SSMALL(ires));
-		    if (MY_IS_SSMALL(ires)) {
+		    if (IS_SSMALL(ires)) {
 			return make_small(ires);
 		    } else {
 			if (ERTS_NEED_GC(p, 2)) {
diff --git a/erts/emulator/beam/erl_async.c b/erts/emulator/beam/erl_async.c
index 9a93034fcb..3ceb2fd368 100644
--- a/erts/emulator/beam/erl_async.c
+++ b/erts/emulator/beam/erl_async.c
@@ -34,9 +34,6 @@
 
 #define ERTS_ASYNC_PRINT_JOB 0
 
-#if !defined(ERTS_SMP) && defined(USE_THREADS) && !ERTS_USE_ASYNC_READY_Q
-#  error "Need async ready queue in non-smp case"
-#endif
 
 typedef struct _erl_async {
     DE_Handle*         hndl;   /* The DE_Handle is needed when port is gone */
@@ -46,16 +43,13 @@ typedef struct _erl_async {
     ErlDrvPDL          pdl;
     void (*async_invoke)(void*);
     void (*async_free)(void*);
-#if ERTS_USE_ASYNC_READY_Q
     Uint               sched_id;
     union {
 	ErtsThrQPrepEnQ_t *prep_enq;
 	ErtsThrQFinDeQ_t   fin_deq;
     } q;
-#endif
 } ErtsAsync;
 
-#if ERTS_USE_ASYNC_READY_Q
 
 /*
  * We can do without the enqueue mutex since it isn't needed for
@@ -94,7 +88,6 @@ typedef union {
     char align__[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(ErtsAsyncReadyQ))];
 } ErtsAlgndAsyncReadyQ;
 
-#endif /* ERTS_USE_ASYNC_READY_Q */
 
 typedef struct {
     ErtsThrQ_t thr_q;
@@ -119,12 +112,10 @@ typedef struct {
 	char align__[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(ErtsAsyncInit))];
     } init;
     ErtsAlgndAsyncQ *queue;
-#if ERTS_USE_ASYNC_READY_Q
     ErtsAlgndAsyncReadyQ *ready_queue;
-#endif
 } ErtsAsyncData;
 
-#if defined(USE_THREADS) && defined(USE_VM_PROBES)
+#if defined(USE_VM_PROBES)
 
 /*
  * Some compilers, e.g. GCC 4.2.1 and -O3, will optimize away DTrace
@@ -140,15 +131,6 @@ int erts_async_thread_suggested_stack_size; /* Initialized by erl_init.c */
 
 static ErtsAsyncData *async;
 
-#ifndef USE_THREADS
-
-void
-erts_init_async(void)
-{
-
-}
-
-#else
 
 static void *async_main(void *);
 
@@ -158,7 +140,6 @@ async_q(int i)
     return &async->queue[i].aq;
 }
 
-#if ERTS_USE_ASYNC_READY_Q
 
 static ERTS_INLINE ErtsAsyncReadyQ *
 async_ready_q(Uint sched_id)
@@ -166,16 +147,13 @@ async_ready_q(Uint sched_id)
     return &async->ready_queue[((int)sched_id)-1].arq;
 }
 
-#endif
 
 void
 erts_init_async(void)
 {
     async = NULL;
     if (erts_async_max_threads > 0) {
-#if ERTS_USE_ASYNC_READY_Q
 	ErtsThrQInit_t qinit = ERTS_THR_Q_INIT_DEFAULT;
-#endif
 	erts_thr_opts_t thr_opts = ERTS_THR_OPTS_DEFAULT_INITER;
 	char *ptr, thr_name[16];
 	size_t tot_size = 0;
@@ -183,9 +161,7 @@ erts_init_async(void)
 
 	tot_size += ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(ErtsAsyncData));
 	tot_size += sizeof(ErtsAlgndAsyncQ)*erts_async_max_threads;
-#if ERTS_USE_ASYNC_READY_Q
 	tot_size += sizeof(ErtsAlgndAsyncReadyQ)*erts_no_schedulers;
-#endif
 
 	ptr = erts_alloc_permanent_cache_aligned(ERTS_ALC_T_ASYNC_DATA,
 						 tot_size);
@@ -202,7 +178,6 @@ erts_init_async(void)
 	async->queue = (ErtsAlgndAsyncQ *) ptr;
 	ptr += sizeof(ErtsAlgndAsyncQ)*erts_async_max_threads;
 
-#if ERTS_USE_ASYNC_READY_Q
 
 	qinit.live.queue = ERTS_THR_Q_LIVE_LONG;
 	qinit.live.objects = ERTS_THR_Q_LIVE_SHORT;
@@ -222,7 +197,6 @@ erts_init_async(void)
 	    erts_thr_q_initialize(&arq->thr_q, &qinit);
 	}
 
-#endif
 
 	/* Create async threads... */
 
@@ -253,7 +227,6 @@ erts_init_async(void)
     }
 }
 
-#if ERTS_USE_ASYNC_READY_Q
 
 void *
 erts_get_async_ready_queue(Uint sched_id)
@@ -261,7 +234,6 @@ erts_get_async_ready_queue(Uint sched_id)
     return (void *) async ? async_ready_q(sched_id) : NULL;
 }
 
-#endif
 
 static ERTS_INLINE void async_add(ErtsAsync *a, ErtsAsyncQ* q)
 {
@@ -270,10 +242,8 @@ static ERTS_INLINE void async_add(ErtsAsync *a, ErtsAsyncQ* q)
 #endif
 
     if (is_internal_port(a->port)) {
-#if ERTS_USE_ASYNC_READY_Q
 	ErtsAsyncReadyQ *arq = async_ready_q(a->sched_id);
 	a->q.prep_enq = erts_thr_q_prepare_enqueue(&arq->thr_q);
-#endif
 	/* make sure the driver will stay around */
 	if (a->hndl)
 	    erts_ddll_reference_referenced_driver(a->hndl);
@@ -309,10 +279,8 @@ static ERTS_INLINE ErtsAsync *async_get(ErtsThrQ_t *q,
 					erts_tse_t *tse,
 					ErtsThrQPrepEnQ_t **prep_enq)
 {
-#if ERTS_USE_ASYNC_READY_Q
     int saved_fin_deq = 0;
     ErtsThrQFinDeQ_t fin_deq;
-#endif
 #ifdef USE_VM_PROBES
     int len;
 #endif
@@ -321,12 +289,10 @@ static ERTS_INLINE ErtsAsync *async_get(ErtsThrQ_t *q,
 	ErtsAsync *a = (ErtsAsync *) erts_thr_q_dequeue(q);
 	if (a) {
 
-#if ERTS_USE_ASYNC_READY_Q
 	    *prep_enq = a->q.prep_enq;
 	    erts_thr_q_get_finalize_dequeue_data(q, &a->q.fin_deq);
 	    if (saved_fin_deq)
 		erts_thr_q_append_finalize_dequeue_data(&a->q.fin_deq, &fin_deq);
-#endif
 #ifdef USE_LTTNG_VM_TRACEPOINTS
             if (LTTNG_ENABLED(aio_pool_get)) {
                 lttng_decl_portbuf(port_str);
@@ -354,7 +320,6 @@ static ERTS_INLINE ErtsAsync *async_get(ErtsThrQ_t *q,
 
 	    erts_tse_reset(tse);
 
-#if ERTS_USE_ASYNC_READY_Q
 	chk_fin_deq:
 	    if (erts_thr_q_get_finalize_dequeue_data(q, &tmp_fin_deq)) {
 		if (!saved_fin_deq) {
@@ -364,13 +329,11 @@ static ERTS_INLINE ErtsAsync *async_get(ErtsThrQ_t *q,
 		erts_thr_q_append_finalize_dequeue_data(&fin_deq,
 							&tmp_fin_deq);
 	    }
-#endif
 
 	    switch (erts_thr_q_inspect(q, 1)) {
 	    case ERTS_THR_Q_DIRTY:
 		break;
 	    case ERTS_THR_Q_NEED_THR_PRGR:
-#ifdef ERTS_SMP
 	    {
 		ErtsThrPrgrVal prgr = erts_thr_q_need_thr_progress(q);
 		erts_thr_progress_wakeup(NULL, prgr);
@@ -382,17 +345,14 @@ static ERTS_INLINE ErtsAsync *async_get(ErtsThrQ_t *q,
 		erts_tse_wait(tse);
 		break;
 	    }
-#endif
 	    case ERTS_THR_Q_CLEAN:
 
-#if ERTS_USE_ASYNC_READY_Q
 		if (saved_fin_deq) {
 		    if (erts_thr_q_finalize_dequeue(&fin_deq))
 			goto chk_fin_deq;
 		    else
 			saved_fin_deq = 0;
 		}
-#endif
 
 		erts_tse_wait(tse);
 		break;
@@ -408,15 +368,10 @@ static ERTS_INLINE ErtsAsync *async_get(ErtsThrQ_t *q,
 
 static ERTS_INLINE void call_async_ready(ErtsAsync *a)
 {
-#if ERTS_USE_ASYNC_READY_Q
     Port *p = erts_id2port_sflgs(a->port,
 				 NULL,
 				 0,
 				 ERTS_PORT_SFLGS_INVALID_DRIVER_LOOKUP);
-#else
-    Port *p = erts_thr_id2port_sflgs(a->port,
-				     ERTS_PORT_SFLGS_INVALID_DRIVER_LOOKUP);
-#endif
     if (!p) {
 	if (a->async_free) {
             ERTS_MSACC_PUSH_AND_SET_STATE(ERTS_MSACC_STATE_PORT);
@@ -432,11 +387,7 @@ static ERTS_INLINE void call_async_ready(ErtsAsync *a)
                 ERTS_MSACC_POP_STATE();
             }
 	}
-#if ERTS_USE_ASYNC_READY_Q
 	erts_port_release(p);
-#else
-	erts_thr_port_release(p);
-#endif
     }
     if (a->pdl)
 	driver_pdl_dec_refc(a->pdl);
@@ -446,7 +397,6 @@ static ERTS_INLINE void call_async_ready(ErtsAsync *a)
 
 static ERTS_INLINE void async_reply(ErtsAsync *a, ErtsThrQPrepEnQ_t *prep_enq)
 {
-#if ERTS_USE_ASYNC_READY_Q
     ErtsAsyncReadyQ *arq;
 
 #if ERTS_ASYNC_PRINT_JOB
@@ -465,12 +415,6 @@ static ERTS_INLINE void async_reply(ErtsAsync *a, ErtsThrQPrepEnQ_t *prep_enq)
 	erts_mtx_unlock(&arq->x.data.enq_mtx);
 #endif
 
-#else /* ERTS_USE_ASYNC_READY_Q */
-
-	call_async_ready(a);
-	erts_free(ERTS_ALC_T_ASYNC, (void *) a);
-
-#endif /* ERTS_USE_ASYNC_READY_Q */
 }
 
 
@@ -486,7 +430,6 @@ static erts_tse_t *async_thread_init(ErtsAsyncQ *aq)
     erts_tse_t *tse = erts_tse_fetch();
     ERTS_DECLARE_DUMMY(Uint no);
 
-#ifdef ERTS_SMP
     ErtsThrPrgrCallbacks callbacks;
 
     callbacks.arg = (void *) tse;
@@ -495,15 +438,12 @@ static erts_tse_t *async_thread_init(ErtsAsyncQ *aq)
     callbacks.wait = NULL;
 
     erts_thr_progress_register_unmanaged_thread(&callbacks);
-#endif
 
     qinit.live.queue = ERTS_THR_Q_LIVE_LONG;
     qinit.live.objects = ERTS_THR_Q_LIVE_SHORT;
     qinit.arg = (void *) tse;
     qinit.notify = async_wakeup;
-#if ERTS_USE_ASYNC_READY_Q
     qinit.auto_finalize_dequeue = 0;
-#endif
 
     erts_thr_q_initialize(&aq->thr_q, &qinit);
 
@@ -545,12 +485,10 @@ static void *async_main(void* arg)
     return NULL;
 }
 
-#endif /* USE_THREADS */
 
 void
 erts_exit_flush_async(void)
 {
-#ifdef USE_THREADS
     int i;
     ErtsAsync a;
     a.port = NIL;
@@ -564,11 +502,8 @@ erts_exit_flush_async(void)
 	async_add(&a, async_q(i));
     for (i = 0; i < erts_async_max_threads; i++)
 	erts_thr_join(async->queue[i].aq.thr_id, NULL);
-#endif
 }
 
-#if defined(USE_THREADS) && ERTS_USE_ASYNC_READY_Q
-
 int erts_check_async_ready(void *varq)
 {
     ErtsAsyncReadyQ *arq = (ErtsAsyncReadyQ *) varq;
@@ -609,18 +544,15 @@ int erts_async_ready_clean(void *varq, void *val)
     case ERTS_THR_Q_DIRTY:
 	return ERTS_ASYNC_READY_DIRTY;
     case ERTS_THR_Q_NEED_THR_PRGR:
-#ifdef ERTS_SMP
 	*((ErtsThrPrgrVal *) val)
 	    = erts_thr_q_need_thr_progress(&arq->thr_q);
 	return ERTS_ASYNC_READY_NEED_THR_PRGR;
-#endif
     case ERTS_THR_Q_CLEAN:
 	break;
     }
     return ERTS_ASYNC_READY_CLEAN;
 }
 
-#endif
 
 /*
 ** Generate a fair async key prom an ErlDrvPort
@@ -658,28 +590,22 @@ long driver_async(ErlDrvPort ix, unsigned int* key,
     Port* prt;
     long id;
     unsigned int qix;
-#if ERTS_USE_ASYNC_READY_Q
     Uint sched_id;
     ERTS_MSACC_PUSH_STATE();
 
     sched_id = erts_get_scheduler_id();
     if (!sched_id)
 	sched_id = 1;
-#else
-    ERTS_MSACC_PUSH_STATE();
-#endif
 
     prt = erts_drvport2port(ix);
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return -1;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
     a = (ErtsAsync*) erts_alloc(ERTS_ALC_T_ASYNC, sizeof(ErtsAsync));
 
-#if ERTS_USE_ASYNC_READY_Q
     a->sched_id = sched_id;
-#endif
     a->hndl = (DE_Handle*)prt->drv_ptr->handle;
     a->port = prt->common.id;
     a->pdl = NULL;
@@ -709,7 +635,6 @@ long driver_async(ErlDrvPort ix, unsigned int* key,
 	    (*key % erts_async_max_threads) : 0;
 	*key = qix;
     }
-#ifdef USE_THREADS
     if (erts_async_max_threads > 0) {
 	if (prt->port_data_lock) {
 	    driver_pdl_inc_refc(prt->port_data_lock);
@@ -718,7 +643,6 @@ long driver_async(ErlDrvPort ix, unsigned int* key,
 	async_add(a, async_q(qix));
 	return id;
     }
-#endif
     
     ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_PORT);
     (*a->async_invoke)(a->async_data);
diff --git a/erts/emulator/beam/erl_async.h b/erts/emulator/beam/erl_async.h
index 4b470e7679..70ef247e0a 100644
--- a/erts/emulator/beam/erl_async.h
+++ b/erts/emulator/beam/erl_async.h
@@ -27,39 +27,12 @@ extern int erts_async_max_threads;
 #define ERTS_ASYNC_THREAD_MAX_STACK_SIZE 8192	/* Kilo words */
 extern int erts_async_thread_suggested_stack_size;
 
-
-#ifdef ERTS_SMP
-/*
- * With smp support we can choose to have, or not to
- * have an async ready queue.
- */
-#define ERTS_USE_ASYNC_READY_Q 1
-#endif
-
-#ifndef ERTS_SMP
-/* In non-smp case we *need* the async ready queue */
-#  undef ERTS_USE_ASYNC_READY_Q
-#  define ERTS_USE_ASYNC_READY_Q 1
-#endif
-
-#ifndef ERTS_USE_ASYNC_READY_Q
-#  define ERTS_USE_ASYNC_READY_Q 0
-#endif
-
-#ifndef USE_THREADS
-#  undef ERTS_USE_ASYNC_READY_Q
-#  define ERTS_USE_ASYNC_READY_Q 0
-#endif /* !USE_THREADS */
-#if ERTS_USE_ASYNC_READY_Q
 int erts_check_async_ready(void *);
 int erts_async_ready_clean(void *, void *);
 void *erts_get_async_ready_queue(Uint sched_id);
 #define ERTS_ASYNC_READY_CLEAN 0
 #define ERTS_ASYNC_READY_DIRTY 1
-#ifdef ERTS_SMP
 #define ERTS_ASYNC_READY_NEED_THR_PRGR 2
-#endif
-#endif /* ERTS_USE_ASYNC_READY_Q */
 
 void erts_init_async(void);
 void erts_exit_flush_async(void);
diff --git a/erts/emulator/beam/erl_bif_binary.c b/erts/emulator/beam/erl_bif_binary.c
index dcffde5777..4cafa499a9 100644
--- a/erts/emulator/beam/erl_bif_binary.c
+++ b/erts/emulator/beam/erl_bif_binary.c
@@ -171,6 +171,16 @@ static void *my_alloc(MyAllocator *my, Uint size)
 
 #define ALPHABET_SIZE 256
 
+typedef struct _findall_data {
+    Uint pos;
+    Uint len;
+#ifdef HARDDEBUG
+    Uint id;
+#endif
+    Eterm epos;
+    Eterm elen;
+} FindallData;
+
 typedef struct _ac_node {
 #ifdef HARDDEBUG
     Uint32 id;                        /* To identify h pointer targets when
@@ -208,6 +218,103 @@ typedef struct _bm_data {
     Sint badshift[ALPHABET_SIZE];
 } BMData;
 
+typedef struct _ac_find_all_state {
+    ACNode *q;
+    Uint pos;
+    Uint len;
+    Uint m;
+    Uint allocated;
+    FindallData *out;
+} ACFindAllState;
+
+typedef struct _ac_find_first_state {
+    ACNode *q;
+    Uint pos;
+    Uint len;
+    ACNode *candidate;
+    Uint candidate_start;
+} ACFindFirstState;
+
+typedef struct _bm_find_all_state {
+    Sint pos;
+    Sint len;
+    Uint m;
+    Uint allocated;
+    FindallData *out;
+} BMFindAllState;
+
+typedef struct _bm_find_first_state {
+    Sint pos;
+    Sint len;
+} BMFindFirstState;
+
+typedef enum _bf_return {
+    BF_RESTART = -3,
+    BF_NOT_FOUND,
+    BF_BADARG,
+    BF_OK
+} BFReturn;
+
+typedef struct _binary_find_all_context {
+    ErtsHeapFactory factory;
+    Eterm term;
+    Sint head;
+    Sint tail;
+    Uint end_pos;
+    Uint size;
+    FindallData *data;
+    union {
+	ACFindAllState ac;
+	BMFindAllState bm;
+    } d;
+} BinaryFindAllContext;
+
+typedef struct _binary_find_first_context {
+    Uint pos;
+    Uint len;
+    union {
+	ACFindFirstState ac;
+	BMFindFirstState bm;
+    } d;
+} BinaryFindFirstContext;
+
+typedef struct _binary_find_context BinaryFindContext;
+
+typedef struct _binary_find_search {
+    void (*init) (BinaryFindContext *);
+    BFReturn (*find) (BinaryFindContext *, byte *);
+    void (*done) (BinaryFindContext *);
+} BinaryFindSearch;
+
+typedef Eterm (*BinaryFindResult)(Process *, Eterm, BinaryFindContext **);
+
+typedef enum _binary_find_state {
+    BFSearch,
+    BFResult,
+    BFDone
+} BinaryFindState;
+
+struct _binary_find_context {
+    Eterm pat_type;
+    Eterm pat_term;
+    Binary *pat_bin;
+    Uint flags;
+    Uint hsstart;
+    Uint hsend;
+    int loop_factor;
+    int exported;
+    Uint reds;
+    BinaryFindState state;
+    Eterm trap_term;
+    BinaryFindSearch *search;
+    BinaryFindResult not_found;
+    BinaryFindResult found;
+    union {
+	BinaryFindAllContext fa;
+	BinaryFindFirstContext ff;
+    } u;
+};
+
 #ifdef HARDDEBUG
 static void dump_bm_data(BMData *bm);
 static void dump_ac_trie(ACTrie *act);
@@ -414,32 +521,25 @@ static void ac_compute_failure_functions(ACTrie *act, ACNode **qbuff)
  * Basic AC finds the first end before the first start...
  *
  */
-typedef struct {
-    ACNode *q;
-    Uint pos;
-    Uint len;
-    ACNode *candidate;
-    Uint candidate_start;
-} ACFindFirstState;
-
-
-static void ac_init_find_first_match(ACFindFirstState *state, ACTrie *act, Sint startpos, Uint len)
+static void ac_init_find_first_match(BinaryFindContext *ctx)
 {
+    ACFindFirstState *state = &(ctx->u.ff.d.ac);
+    ACTrie *act = ERTS_MAGIC_BIN_DATA(ctx->pat_bin);
     state->q = act->root;
-    state->pos = startpos;
-    state->len = len;
+    state->pos = ctx->hsstart;
+    state->len = ctx->hsend;
     state->candidate = NULL;
     state->candidate_start = 0;
 }
-#define AC_OK 0
-#define AC_NOT_FOUND -1
-#define AC_RESTART -2
 
 #define AC_LOOP_FACTOR 10
 
-static int ac_find_first_match(ACFindFirstState *state, byte *haystack,
-				Uint *mpos, Uint *mlen, Uint *reductions)
+static BFReturn ac_find_first_match(BinaryFindContext *ctx, byte *haystack)
 {
+    ACFindFirstState *state = &(ctx->u.ff.d.ac);
+    Uint *mpos = &(ctx->u.ff.pos);
+    Uint *mlen = &(ctx->u.ff.len);
+    Uint *reductions = &(ctx->reds);
     ACNode *q = state->q;
     Uint i = state->pos;
     ACNode *candidate = state->candidate, *r;
@@ -455,7 +555,7 @@ static int ac_find_first_match(ACFindFirstState *state, byte *haystack,
 	    state->len = len;
 	    state->candidate = candidate;
 	    state->candidate_start = candidate_start;
-	    return AC_RESTART;
+	    return BF_RESTART;
 	}
 
 	while (q->g[haystack[i]] == NULL && q->h != q) {
@@ -485,68 +585,33 @@ static int ac_find_first_match(ACFindFirstState *state, byte *haystack,
     }
     *reductions = reds;
     if (!candidate) {
-	return AC_NOT_FOUND;
+	return BF_NOT_FOUND;
     }
 #ifdef HARDDEBUG
     dump_ac_node(candidate,0,'?');
 #endif
     *mpos = candidate_start;
     *mlen = candidate->d;
-    return AC_OK;
+    return BF_OK;
 }
 
-typedef struct _findall_data {
-    Uint pos;
-    Uint len;
-#ifdef HARDDEBUG
-    Uint id;
-#endif
-    Eterm epos;
-    Eterm elen;
-} FindallData;
-
-typedef struct {
-    ACNode *q;
-    Uint pos;
-    Uint len;
-    Uint m;
-    Uint allocated;
-    FindallData *out;
-} ACFindAllState;
-
-static void ac_init_find_all(ACFindAllState *state, ACTrie *act, Sint startpos, Uint len)
+static void ac_init_find_all(BinaryFindContext *ctx)
 {
+    ACFindAllState *state = &(ctx->u.fa.d.ac);
+    ACTrie *act = ERTS_MAGIC_BIN_DATA(ctx->pat_bin);
     state->q = act->root;
-    state->pos = startpos;
-    state->len = len;
+    state->pos = ctx->hsstart;
+    state->len = ctx->hsend;
     state->m = 0;
     state->allocated = 0;
     state->out = NULL;
 }
 
-static void ac_restore_find_all(ACFindAllState *state,
-                                const ACFindAllState *src)
-{
-    memcpy(state, src, sizeof(ACFindAllState));
-    if (state->allocated > 0) {
-	state->out = erts_alloc(ERTS_ALC_T_TMP, sizeof(FindallData) * (state->allocated));
-	memcpy(state->out, src+1, sizeof(FindallData)*state->m);
-    } else {
-	state->out = NULL;
-    }
-}
-
-static void ac_serialize_find_all(const ACFindAllState *state,
-                                  ACFindAllState *dst)
-{
-    memcpy(dst, state, sizeof(ACFindAllState));
-    memcpy(dst+1, state->out, sizeof(FindallData)*state->m);
-}
-
-static void ac_clean_find_all(ACFindAllState *state)
+static void ac_clean_find_all(BinaryFindContext *ctx)
 {
+    ACFindAllState *state = &(ctx->u.fa.d.ac);
     if (state->out != NULL) {
-	erts_free(ERTS_ALC_T_TMP, state->out);
+	erts_free(ERTS_ALC_T_BINARY_FIND, state->out);
     }
 #ifdef HARDDEBUG
     state->out = NULL;
@@ -558,9 +623,10 @@ static void ac_clean_find_all(ACFindAllState *state)
  * Differs to the find_first function in that it stores all matches and the values
  * arte returned only in the state.
  */
-static int ac_find_all_non_overlapping(ACFindAllState *state, byte *haystack,
-				       Uint *reductions)
+static BFReturn ac_find_all_non_overlapping(BinaryFindContext *ctx, byte *haystack)
 {
+    ACFindAllState *state = &(ctx->u.fa.d.ac);
+    Uint *reductions = &(ctx->reds);
     ACNode *q = state->q;
     Uint i = state->pos;
     Uint rstart;
@@ -571,7 +637,6 @@ static int ac_find_all_non_overlapping(ACFindAllState *state, byte *haystack,
     FindallData *out = state->out;
     register Uint reds = *reductions;
 
-
     while (i < len) {
 	if (--reds == 0) {
 	    state->q = q;
@@ -580,7 +645,7 @@ static int ac_find_all_non_overlapping(ACFindAllState *state, byte *haystack,
 	    state->m = m;
 	    state->allocated = allocated;
 	    state->out = out;
-	    return AC_RESTART;
+	    return BF_RESTART;
 	}
 	while (q->g[haystack[i]] == NULL && q->h != q) {
 	    q = q->h;
@@ -618,11 +683,11 @@ static int ac_find_all_non_overlapping(ACFindAllState *state, byte *haystack,
 		    if (m >= allocated) {
 			if (!allocated) {
 			    allocated = 10;
-			    out = erts_alloc(ERTS_ALC_T_TMP,
+			    out = erts_alloc(ERTS_ALC_T_BINARY_FIND,
 					     sizeof(FindallData) * allocated);
 			} else {
 			    allocated *= 2;
-			    out = erts_realloc(ERTS_ALC_T_TMP, out,
+			    out = erts_realloc(ERTS_ALC_T_BINARY_FIND, out,
 					       sizeof(FindallData) *
 					       allocated);
 			}
@@ -649,7 +714,7 @@ static int ac_find_all_non_overlapping(ACFindAllState *state, byte *haystack,
     *reductions = reds;
     state->m = m;
     state->out = out;
-    return (m == 0) ? AC_NOT_FOUND : AC_OK;
+    return (m == 0) ? BF_NOT_FOUND : BF_OK;
 }
 
 /*
@@ -736,27 +801,22 @@ static void compute_goodshifts(BMData *bmd)
     erts_free(ERTS_ALC_T_TMP, suffixes);
 }
 
-typedef struct {
-    Sint pos;
-    Sint len;
-} BMFindFirstState;
-
-#define BM_OK 0 /* used only for find_all */
-#define BM_NOT_FOUND -1
-#define BM_RESTART -2
 #define BM_LOOP_FACTOR 10 /* Should we have a higher value? */
 
-static void bm_init_find_first_match(BMFindFirstState *state, Sint startpos,
-				     Uint len)
+static void bm_init_find_first_match(BinaryFindContext *ctx)
 {
-    state->pos = startpos;
-    state->len = (Sint) len;
+    BMFindFirstState *state = &(ctx->u.ff.d.bm);
+    state->pos = ctx->hsstart;
+    state->len = ctx->hsend;
 }
 
-
-static Sint bm_find_first_match(BMFindFirstState *state, BMData *bmd,
-				byte *haystack, Uint *reductions)
+static BFReturn bm_find_first_match(BinaryFindContext *ctx, byte *haystack)
 {
+    BMFindFirstState *state = &(ctx->u.ff.d.bm);
+    BMData *bmd = ERTS_MAGIC_BIN_DATA(ctx->pat_bin);
+    Uint *mpos = &(ctx->u.ff.pos);
+    Uint *mlen = &(ctx->u.ff.len);
+    Uint *reductions = &(ctx->reds);
     Sint blen = bmd->len;
     Sint len = state->len;
     Sint *gs = bmd->goodshift;
@@ -769,61 +829,37 @@ static Sint bm_find_first_match(BMFindFirstState *state, BMData *bmd,
     while (j <= len - blen) {
 	if (--reds == 0) {
 	    state->pos = j;
-	    return BM_RESTART;
+	    return BF_RESTART;
 	}
 	for (i = blen - 1; i >= 0 && needle[i] == haystack[i + j]; --i)
 	    ;
 	if (i < 0) { /* found */
 	    *reductions = reds;
-	    return j;
+	    *mpos = (Uint) j;
+	    *mlen = (Uint) blen;
+	    return BF_OK;
 	}
 	j += MAX(gs[i],bs[haystack[i+j]] - blen + 1 + i);
     }
     *reductions = reds;
-    return BM_NOT_FOUND;
+    return BF_NOT_FOUND;
 }
 
-typedef struct {
-    Sint pos;
-    Sint len;
-    Uint m;
-    Uint allocated;
-    FindallData *out;
-} BMFindAllState;
-
-static void bm_init_find_all(BMFindAllState *state, Sint startpos, Uint len)
+static void bm_init_find_all(BinaryFindContext *ctx)
 {
-    state->pos = startpos;
-    state->len = (Sint) len;
+    BMFindAllState *state = &(ctx->u.fa.d.bm);
+    state->pos = ctx->hsstart;
+    state->len = ctx->hsend;
     state->m = 0;
     state->allocated = 0;
     state->out = NULL;
 }
 
-static void bm_restore_find_all(BMFindAllState *state,
-                                const BMFindAllState *src)
-{
-    memcpy(state, src, sizeof(BMFindAllState));
-    if (state->allocated > 0) {
-	state->out = erts_alloc(ERTS_ALC_T_TMP, sizeof(FindallData) *
-				(state->allocated));
-	memcpy(state->out, src+1, sizeof(FindallData)*state->m);
-    } else {
-	state->out = NULL;
-    }
-}
-
-static void bm_serialize_find_all(const BMFindAllState *state,
-                                  BMFindAllState *dst)
-{
-    memcpy(dst, state, sizeof(BMFindAllState));
-    memcpy(dst+1, state->out, sizeof(FindallData)*state->m);
-}
-
-static void bm_clean_find_all(BMFindAllState *state)
+static void bm_clean_find_all(BinaryFindContext *ctx)
 {
+    BMFindAllState *state = &(ctx->u.fa.d.bm);
     if (state->out != NULL) {
-	erts_free(ERTS_ALC_T_TMP, state->out);
+	erts_free(ERTS_ALC_T_BINARY_FIND, state->out);
     }
 #ifdef HARDDEBUG
     state->out = NULL;
@@ -835,10 +871,11 @@ static void bm_clean_find_all(BMFindAllState *state)
  * Differs to the find_first function in that it stores all matches and the
  * values are returned only in the state.
  */
-static Sint bm_find_all_non_overlapping(BMFindAllState *state,
-					BMData *bmd, byte *haystack,
-					Uint *reductions)
+static BFReturn bm_find_all_non_overlapping(BinaryFindContext *ctx, byte *haystack)
 {
+    BMFindAllState *state = &(ctx->u.fa.d.bm);
+    BMData *bmd = ERTS_MAGIC_BIN_DATA(ctx->pat_bin);
+    Uint *reductions = &(ctx->reds);
     Sint blen = bmd->len;
     Sint len = state->len;
     Sint *gs = bmd->goodshift;
@@ -857,7 +894,7 @@ static Sint bm_find_all_non_overlapping(BMFindAllState *state,
 	    state->m = m;
 	    state->allocated = allocated;
 	    state->out = out;
-	    return BM_RESTART;
+	    return BF_RESTART;
 	}
 	for (i = blen - 1; i >= 0 && needle[i] == haystack[i + j]; --i)
 	    ;
@@ -865,10 +902,11 @@ static Sint bm_find_all_non_overlapping(BMFindAllState *state,
 	    if (m >= allocated) {
 		if (!allocated) {
 		    allocated = 10;
-		    out = erts_alloc(ERTS_ALC_T_TMP, sizeof(FindallData) * allocated);
+		    out = erts_alloc(ERTS_ALC_T_BINARY_FIND,
+				     sizeof(FindallData) * allocated);
 		} else {
 		    allocated *= 2;
-		    out = erts_realloc(ERTS_ALC_T_TMP, out,
+		    out = erts_realloc(ERTS_ALC_T_BINARY_FIND, out,
 				       sizeof(FindallData) * allocated);
 		}
 	    }
@@ -883,7 +921,7 @@ static Sint bm_find_all_non_overlapping(BMFindAllState *state,
     state->m = m;
     state->out = out;
     *reductions = reds;
-    return (m == 0) ? BM_NOT_FOUND : BM_OK;
+    return (m == 0) ? BF_NOT_FOUND : BF_OK;
 }
 
 /*
@@ -1009,51 +1047,160 @@ BIF_RETTYPE binary_compile_pattern_1(BIF_ALIST_1)
     BIF_RET(ret);
 }
 
-#define DO_BIN_MATCH_OK 0
-#define DO_BIN_MATCH_BADARG -1
-#define DO_BIN_MATCH_RESTART -2
+#define BF_FLAG_GLOBAL		0x01
+#define BF_FLAG_SPLIT_TRIM	0x02
+#define BF_FLAG_SPLIT_TRIM_ALL	0x04
 
-#define BINARY_FIND_ALL		0x01
-#define BINARY_SPLIT_TRIM	0x02
-#define BINARY_SPLIT_TRIM_ALL	0x04
+static void bf_context_init(BinaryFindContext *ctx, BinaryFindResult not_found,
+			    BinaryFindResult single, BinaryFindResult global,
+			    Binary *pat_bin);
+static BinaryFindContext *bf_context_export(Process *p, BinaryFindContext *src);
+static int bf_context_destructor(Binary *ctx_bin);
+#ifdef HARDDEBUG
+static void bf_context_dump(BinaryFindContext *ctx);
+#endif
 
-typedef struct BinaryFindState {
-    Eterm type;
-    Uint  flags;
-    Uint  hsstart;
-    Uint  hsend;
-    Eterm (*not_found_result) (Process *, Eterm, struct BinaryFindState *);
-    Eterm (*single_result)    (Process *, Eterm, struct BinaryFindState *, Sint, Sint);
-    Eterm (*global_result)    (Process *, Eterm, struct BinaryFindState *, FindallData *, Uint);
-} BinaryFindState;
+static BinaryFindSearch bf_search_ac_global = {
+    ac_init_find_all,
+    ac_find_all_non_overlapping,
+    ac_clean_find_all
+};
+
+static BinaryFindSearch bf_search_ac_single = {
+    ac_init_find_first_match,
+    ac_find_first_match,
+    NULL
+};
+
+static BinaryFindSearch bf_search_bm_global = {
+    bm_init_find_all,
+    bm_find_all_non_overlapping,
+    bm_clean_find_all
+};
+
+static BinaryFindSearch bf_search_bm_single = {
+    bm_init_find_first_match,
+    bm_find_first_match,
+    NULL
+};
+
+static void bf_context_init(BinaryFindContext *ctx, BinaryFindResult not_found,
+			    BinaryFindResult single, BinaryFindResult global,
+			    Binary *pat_bin)
+{
+    ctx->exported = 0;
+    ctx->state = BFSearch;
+    ctx->not_found = not_found;
+    if (ctx->flags & BF_FLAG_GLOBAL) {
+	ctx->found = global;
+	if (ctx->pat_type == am_bm) {
+	    ctx->search = &bf_search_bm_global;
+	    ctx->loop_factor = BM_LOOP_FACTOR;
+	} else if (ctx->pat_type == am_ac) {
+	    ctx->search = &bf_search_ac_global;
+	    ctx->loop_factor = AC_LOOP_FACTOR;
+	}
+    } else {
+	ctx->found = single;
+	if (ctx->pat_type == am_bm) {
+	    ctx->search = &bf_search_bm_single;
+	    ctx->loop_factor = BM_LOOP_FACTOR;
+	} else if (ctx->pat_type == am_ac) {
+	    ctx->search = &bf_search_ac_single;
+	    ctx->loop_factor = AC_LOOP_FACTOR;
+	}
+    }
+    ctx->trap_term = THE_NON_VALUE;
+    ctx->pat_bin = pat_bin;
+    ctx->search->init(ctx);
+}
 
-typedef struct BinaryFindState_bignum {
-    Eterm           bignum_hdr;
-    BinaryFindState bfs;
-    union {
-	BMFindFirstState bmffs;
-	BMFindAllState   bmfas;
-	ACFindFirstState acffs;
-	ACFindAllState   acfas;
-    } data;
-} BinaryFindState_bignum;
-
-#define SIZEOF_BINARY_FIND_STATE(S) \
-	  (sizeof(BinaryFindState)+sizeof(S))
-
-#define SIZEOF_BINARY_FIND_ALL_STATE(S) \
-	  (sizeof(BinaryFindState)+sizeof(S)+(sizeof(FindallData)*(S).m))
-
-static Eterm do_match_not_found_result(Process *p, Eterm subject, BinaryFindState *bfs);
-static Eterm do_match_single_result(Process *p, Eterm subject, BinaryFindState *bfs,
-				    Sint pos, Sint len);
-static Eterm do_match_global_result(Process *p, Eterm subject, BinaryFindState *bfs,
-				    FindallData *fad, Uint fad_sz);
-static Eterm do_split_not_found_result(Process *p, Eterm subject, BinaryFindState *bfs);
-static Eterm do_split_single_result(Process *p, Eterm subject, BinaryFindState *bfs,
-				    Sint pos, Sint len);
-static Eterm do_split_global_result(Process *p, Eterm subject, BinaryFindState *bfs,
-				    FindallData *fad, Uint fad_sz);
+static BinaryFindContext *bf_context_export(Process *p, BinaryFindContext *src)
+{
+    Binary *ctx_bin;
+    BinaryFindContext *ctx;
+    Eterm *hp;
+
+    ASSERT(src->exported == 0);
+    ctx_bin = erts_create_magic_binary(sizeof(BinaryFindContext),
+				       bf_context_destructor);
+    ctx = ERTS_MAGIC_BIN_DATA(ctx_bin);
+    sys_memcpy(ctx, src, sizeof(BinaryFindContext));
+    if (ctx->pat_bin != NULL && ctx->pat_term == THE_NON_VALUE) {
+	hp = HAlloc(p, ERTS_MAGIC_REF_THING_SIZE * 2);
+	ctx->pat_term = erts_mk_magic_ref(&hp, &MSO(p), ctx->pat_bin);
+    } else {
+	hp = HAlloc(p, ERTS_MAGIC_REF_THING_SIZE);
+    }
+    ctx->trap_term = erts_mk_magic_ref(&hp, &MSO(p), ctx_bin);
+    ctx->exported = 1;
+    return ctx;
+}
+
+static int bf_context_destructor(Binary *ctx_bin)
+{
+    BinaryFindContext *ctx;
+
+    ctx = ERTS_MAGIC_BIN_DATA(ctx_bin);
+    if (ctx->state != BFDone) {
+	if (ctx->search->done != NULL) {
+	    ctx->search->done(ctx);
+	}
+	ctx->state = BFDone;
+    }
+    return 1;
+}
+
+#ifdef HARDDEBUG
+static void bf_context_dump(BinaryFindContext *ctx)
+{
+    if (ctx->pat_type == am_bm) {
+	BMData *bm;
+	bm = ERTS_MAGIC_BIN_DATA(ctx->pat_bin);
+	dump_bm_data(bm);
+    } else {
+	ACTrie *act;
+	act = ERTS_MAGIC_BIN_DATA(ctx->pat_bin);
+	dump_ac_trie(act);
+    }
+}
+#endif
+
+static Eterm do_match_not_found_result(Process *p, Eterm subject, BinaryFindContext **ctxp);
+static Eterm do_match_single_result(Process *p, Eterm subject, BinaryFindContext **ctxp);
+static Eterm do_match_global_result(Process *p, Eterm subject, BinaryFindContext **ctxp);
+static Eterm do_split_not_found_result(Process *p, Eterm subject, BinaryFindContext **ctxp);
+static Eterm do_split_single_result(Process *p, Eterm subject, BinaryFindContext **ctxp);
+static Eterm do_split_global_result(Process *p, Eterm subject, BinaryFindContext **ctxp);
+
+static BFReturn maybe_binary_match_compile(BinaryFindContext *ctx, Eterm arg, Binary **pat_bin)
+{
+    Eterm *tp;
+    ctx->pat_term = THE_NON_VALUE;
+    if (is_tuple(arg)) {
+	tp = tuple_val(arg);
+	if (arityval(*tp) != 2 || is_not_atom(tp[1])) {
+	    return BF_BADARG;
+	}
+	if (((tp[1] != am_bm) && (tp[1] != am_ac)) ||
+	    !is_internal_magic_ref(tp[2])) {
+	    return BF_BADARG;
+	}
+	*pat_bin = erts_magic_ref2bin(tp[2]);
+	if ((tp[1] == am_bm &&
+	     ERTS_MAGIC_BIN_DESTRUCTOR(*pat_bin) != cleanup_my_data_bm) ||
+	    (tp[1] == am_ac &&
+	     ERTS_MAGIC_BIN_DESTRUCTOR(*pat_bin) != cleanup_my_data_ac)) {
+	    *pat_bin = NULL;
+	    return BF_BADARG;
+	}
+	ctx->pat_type = tp[1];
+	ctx->pat_term = tp[2];
+    } else if (do_binary_match_compile(arg, &(ctx->pat_type), pat_bin) != 0) {
+	return BF_BADARG;
+    }
+    return BF_OK;
+}
 
 static int parse_match_opts_list(Eterm l, Eterm bin, Uint *posp, Uint *endp)
 {
@@ -1134,17 +1281,17 @@ static int parse_split_opts_list(Eterm l, Eterm bin, Uint *posp, Uint *endp, Uin
 	    Uint orig_size;
 	    if (is_atom(t)) {
 		if (t == am_global) {
-		    *optp |= BINARY_FIND_ALL;
+		    *optp |= BF_FLAG_GLOBAL;
 		    l = CDR(list_val(l));
 		    continue;
 		}
 		if (t == am_trim) {
-		    *optp |= BINARY_SPLIT_TRIM;
+		    *optp |= BF_FLAG_SPLIT_TRIM;
 		    l = CDR(list_val(l));
 		    continue;
 		}
 		if (t == am_trim_all) {
-		    *optp |= BINARY_SPLIT_TRIM_ALL;
+		    *optp |= BF_FLAG_SPLIT_TRIM_ALL;
 		    l = CDR(list_val(l));
 		    continue;
 		}
@@ -1197,266 +1344,160 @@ static int parse_split_opts_list(Eterm l, Eterm bin, Uint *posp, Uint *endp, Uin
     }
 }
 
-static int do_binary_find(Process *p, Eterm subject, BinaryFindState *bfs, Binary *bin,
-			  Eterm state_term, Eterm *res_term)
+static BFReturn do_binary_find(Process *p, Eterm subject, BinaryFindContext **ctxp,
+			       Binary *pat_bin, Binary *ctx_bin, Eterm *res_term)
 {
-    byte *bytes;
-    Uint bitoffs, bitsize;
-    byte *temp_alloc = NULL;
-    BinaryFindState_bignum *state_ptr = NULL;
+    BinaryFindContext *ctx;
+    int is_first_call;
+    Uint initial_reds;
+    BFReturn runres;
 
-    ERTS_GET_BINARY_BYTES(subject, bytes, bitoffs, bitsize);
-    if (bitsize != 0) {
-	goto badarg;
-    }
-    if (bitoffs != 0) {
-	bytes = erts_get_aligned_binary_bytes(subject, &temp_alloc);
-    }
-    if (state_term != NIL) {
-	state_ptr = (BinaryFindState_bignum *)(big_val(state_term));
-	bfs = &(state_ptr->bfs);
+    if (ctx_bin == NULL) {
+	is_first_call = 1;
+	ctx = *ctxp;
+    } else {
+	is_first_call = 0;
+	ctx = ERTS_MAGIC_BIN_DATA(ctx_bin);
+	ctx->pat_bin = pat_bin;
+	*ctxp = ctx;
     }
 
-    if (bfs->flags & BINARY_FIND_ALL) {
-	if (bfs->type == am_bm) {
-	    BMData *bm;
-	    Sint pos;
-	    BMFindAllState state;
-	    Uint reds = get_reds(p, BM_LOOP_FACTOR);
-	    Uint save_reds = reds;
+    initial_reds = ctx->reds = get_reds(p, ctx->loop_factor);
 
-	    bm = (BMData *) ERTS_MAGIC_BIN_DATA(bin);
-#ifdef HARDDEBUG
-	    dump_bm_data(bm);
-#endif
-	    if (state_term == NIL) {
-		bm_init_find_all(&state, bfs->hsstart, bfs->hsend);
-	    } else {
-		bm_restore_find_all(&state, &(state_ptr->data.bmfas));
-	    }
+    switch (ctx->state) {
+    case BFSearch: {
+	byte *bytes;
+	Uint bitoffs, bitsize;
+	byte *temp_alloc = NULL;
 
-	    pos = bm_find_all_non_overlapping(&state, bm, bytes, &reds);
-	    if (pos == BM_NOT_FOUND) {
-		*res_term = bfs->not_found_result(p, subject, bfs);
-	    } else if (pos == BM_RESTART) {
-		int x =
-		    (SIZEOF_BINARY_FIND_ALL_STATE(state) / sizeof(Eterm)) +
-		    !!(SIZEOF_BINARY_FIND_ALL_STATE(state) % sizeof(Eterm));
-#ifdef HARDDEBUG
-		erts_printf("Trap bm!\n");
-#endif
-		state_ptr = (BinaryFindState_bignum*) HAlloc(p, x+1);
-		state_ptr->bignum_hdr = make_pos_bignum_header(x);
-		memcpy(&state_ptr->bfs, bfs, sizeof(BinaryFindState));
-		bm_serialize_find_all(&state, &state_ptr->data.bmfas);
-		*res_term = make_big(&state_ptr->bignum_hdr);
-		erts_free_aligned_binary_bytes(temp_alloc);
-		bm_clean_find_all(&state);
-		return DO_BIN_MATCH_RESTART;
-	    } else {
-		*res_term = bfs->global_result(p, subject, bfs, state.out, state.m);
-	    }
-	    erts_free_aligned_binary_bytes(temp_alloc);
-	    bm_clean_find_all(&state);
-	    BUMP_REDS(p, (save_reds - reds) / BM_LOOP_FACTOR);
-	    return DO_BIN_MATCH_OK;
-	} else if (bfs->type == am_ac) {
-	    ACTrie *act;
-	    int acr;
-	    ACFindAllState state;
-	    Uint reds = get_reds(p, AC_LOOP_FACTOR);
-	    Uint save_reds = reds;
-
-	    act = (ACTrie *) ERTS_MAGIC_BIN_DATA(bin);
+	ERTS_GET_BINARY_BYTES(subject, bytes, bitoffs, bitsize);
+	if (bitsize != 0) {
+	    goto badarg;
+	}
+	if (bitoffs != 0) {
+	    bytes = erts_get_aligned_binary_bytes(subject, &temp_alloc);
+	}
 #ifdef HARDDEBUG
-	    dump_ac_trie(act);
+	bf_context_dump(ctx);
 #endif
-	    if (state_term == NIL) {
-		ac_init_find_all(&state, act, bfs->hsstart, bfs->hsend);
-	    } else {
-		ac_restore_find_all(&state, &(state_ptr->data.acfas));
-	    }
-	    acr = ac_find_all_non_overlapping(&state, bytes, &reds);
-	    if (acr == AC_NOT_FOUND) {
-		*res_term = bfs->not_found_result(p, subject, bfs);
-	    } else if (acr == AC_RESTART) {
-		int x =
-		    (SIZEOF_BINARY_FIND_ALL_STATE(state) / sizeof(Eterm)) +
-		    !!(SIZEOF_BINARY_FIND_ALL_STATE(state) % sizeof(Eterm));
+	runres = ctx->search->find(ctx, bytes);
+	if (runres == BF_NOT_FOUND) {
+	    *res_term = ctx->not_found(p, subject, &ctx);
+	    *ctxp = ctx;
+	} else if (runres == BF_RESTART) {
 #ifdef HARDDEBUG
+	    if (ctx->pat_type == am_ac) {
 		erts_printf("Trap ac!\n");
-#endif
-                state_ptr = (BinaryFindState_bignum*) HAlloc(p, x+1);
-		state_ptr->bignum_hdr = make_pos_bignum_header(x);
-		memcpy(&state_ptr->bfs, bfs, sizeof(BinaryFindState));
-		ac_serialize_find_all(&state, &state_ptr->data.acfas);
-		*res_term = make_big(&state_ptr->bignum_hdr);
-		erts_free_aligned_binary_bytes(temp_alloc);
-		ac_clean_find_all(&state);
-		return DO_BIN_MATCH_RESTART;
-	    } else {
-		*res_term = bfs->global_result(p, subject, bfs, state.out, state.m);
-	    }
-	    erts_free_aligned_binary_bytes(temp_alloc);
-	    ac_clean_find_all(&state);
-	    BUMP_REDS(p, (save_reds - reds) / AC_LOOP_FACTOR);
-	    return DO_BIN_MATCH_OK;
-	}
-    } else {
-	if (bfs->type == am_bm) {
-	    BMData *bm;
-	    Sint pos;
-	    BMFindFirstState state;
-	    Uint reds = get_reds(p, BM_LOOP_FACTOR);
-	    Uint save_reds = reds;
-
-	    bm = (BMData *) ERTS_MAGIC_BIN_DATA(bin);
-#ifdef HARDDEBUG
-	    dump_bm_data(bm);
-#endif
-	    if (state_term == NIL) {
-		bm_init_find_first_match(&state, bfs->hsstart, bfs->hsend);
 	    } else {
-		memcpy(&state, &state_ptr->data.bmffs, sizeof(BMFindFirstState));
-	    }
-
-#ifdef HARDDEBUG
-	    erts_printf("(bm) state->pos = %ld, state->len = %lu\n",state.pos,
-			state.len);
-#endif
-	    pos = bm_find_first_match(&state, bm, bytes, &reds);
-	    if (pos == BM_NOT_FOUND) {
-		*res_term = bfs->not_found_result(p, subject, bfs);
-	    } else if (pos == BM_RESTART) {
-		int x =
-		    (SIZEOF_BINARY_FIND_STATE(state) / sizeof(Eterm)) +
-		    !!(SIZEOF_BINARY_FIND_STATE(state) % sizeof(Eterm));
-#ifdef HARDDEBUG
 		erts_printf("Trap bm!\n");
+	    }
 #endif
-                state_ptr = (BinaryFindState_bignum*) HAlloc(p, x+1);
-                state_ptr->bignum_hdr = make_pos_bignum_header(x);
-		memcpy(&state_ptr->bfs, bfs, sizeof(BinaryFindState));
-		memcpy(&state_ptr->data.acffs, &state, sizeof(BMFindFirstState));
-		*res_term = make_big(&state_ptr->bignum_hdr);
-		erts_free_aligned_binary_bytes(temp_alloc);
-		return DO_BIN_MATCH_RESTART;
-	    } else {
-		*res_term = bfs->single_result(p, subject, bfs, pos, bm->len);
+	    if (is_first_call) {
+		ctx = bf_context_export(p, ctx);
+		*ctxp = ctx;
+		erts_set_gc_state(p, 0);
 	    }
 	    erts_free_aligned_binary_bytes(temp_alloc);
-	    BUMP_REDS(p, (save_reds - reds) / BM_LOOP_FACTOR);
-	    return DO_BIN_MATCH_OK;
-	} else if (bfs->type == am_ac) {
-	    ACTrie *act;
-	    Uint pos, rlen;
-	    int acr;
-	    ACFindFirstState state;
-	    Uint reds = get_reds(p, AC_LOOP_FACTOR);
-	    Uint save_reds = reds;
-
-	    act = (ACTrie *) ERTS_MAGIC_BIN_DATA(bin);
-#ifdef HARDDEBUG
-	    dump_ac_trie(act);
-#endif
-	    if (state_term == NIL) {
-		ac_init_find_first_match(&state, act, bfs->hsstart, bfs->hsend);
-	    } else {
-		memcpy(&state, &state_ptr->data.acffs, sizeof(ACFindFirstState));
+	    *res_term = THE_NON_VALUE;
+	    BUMP_ALL_REDS(p);
+	    return BF_RESTART;
+	} else {
+	    *res_term = ctx->found(p, subject, &ctx);
+	    *ctxp = ctx;
+	}
+	erts_free_aligned_binary_bytes(temp_alloc);
+	if (*res_term == THE_NON_VALUE) {
+	    if (is_first_call) {
+		erts_set_gc_state(p, 0);
 	    }
-	    acr = ac_find_first_match(&state, bytes, &pos, &rlen, &reds);
-	    if (acr == AC_NOT_FOUND) {
-		*res_term = bfs->not_found_result(p, subject, bfs);
-	    } else if (acr == AC_RESTART) {
-		int x =
-		    (SIZEOF_BINARY_FIND_STATE(state) / sizeof(Eterm)) +
-		    !!(SIZEOF_BINARY_FIND_STATE(state) % sizeof(Eterm));
-#ifdef HARDDEBUG
-		erts_printf("Trap ac!\n");
-#endif
-		state_ptr = (BinaryFindState_bignum*) HAlloc(p, x+1);
-		state_ptr->bignum_hdr = make_pos_bignum_header(x);
-		memcpy(&state_ptr->bfs, bfs, sizeof(BinaryFindState));
-		memcpy(&state_ptr->data.acffs, &state, sizeof(ACFindFirstState));
-		*res_term = make_big(&state_ptr->bignum_hdr);
-		erts_free_aligned_binary_bytes(temp_alloc);
-		return DO_BIN_MATCH_RESTART;
-	    } else {
-		*res_term = bfs->single_result(p, subject, bfs, pos, rlen);
+	    BUMP_ALL_REDS(p);
+	    return BF_RESTART;
+	}
+	if (ctx->search->done != NULL) {
+	    ctx->search->done(ctx);
+	}
+	ctx->state = BFDone;
+	if (!is_first_call) {
+	    erts_set_gc_state(p, 1);
+	}
+	BUMP_REDS(p, (initial_reds - ctx->reds) / ctx->loop_factor);
+	return BF_OK;
+    }
+    case BFResult: {
+	*res_term = ctx->found(p, subject, &ctx);
+	*ctxp = ctx;
+	if (*res_term == THE_NON_VALUE) {
+	    if (is_first_call) {
+		erts_set_gc_state(p, 0);
 	    }
-	    erts_free_aligned_binary_bytes(temp_alloc);
-	    BUMP_REDS(p, (save_reds - reds) / AC_LOOP_FACTOR);
-	    return DO_BIN_MATCH_OK;
+	    BUMP_ALL_REDS(p);
+	    return BF_RESTART;
+	}
+	if (ctx->search->done != NULL) {
+	    ctx->search->done(ctx);
 	}
+	ctx->state = BFDone;
+	if (!is_first_call) {
+	    erts_set_gc_state(p, 1);
+	}
+	BUMP_REDS(p, (initial_reds - ctx->reds) / ctx->loop_factor);
+	return BF_OK;
     }
- badarg:
-    return DO_BIN_MATCH_BADARG;
+    default:
+	ASSERT(!"Unknown state in do_binary_find");
+    }
+
+badarg:
+    if (!is_first_call) {
+	if (ctx->search->done != NULL) {
+	    ctx->search->done(ctx);
+	}
+	ctx->state = BFDone;
+	erts_set_gc_state(p, 1);
+    }
+    return BF_BADARG;
 }
 
 static BIF_RETTYPE
 binary_match(Process *p, Eterm arg1, Eterm arg2, Eterm arg3, Uint flags)
 {
-    BinaryFindState bfs;
-    Eterm *tp;
-    Binary *bin;
-    Eterm bin_term = NIL;
+    BinaryFindContext c_buff;
+    BinaryFindContext *ctx = &c_buff;
+    Binary *pat_bin;
     int runres;
     Eterm result;
 
-    if (is_not_binary(arg1)) {
+    if (is_not_binary(arg1) || binary_bitsize(arg1) != 0) {
 	goto badarg;
     }
-    bfs.flags = flags;
-    if (parse_match_opts_list(arg3, arg1, &(bfs.hsstart), &(bfs.hsend))) {
+    ctx->flags = flags;
+    if (parse_match_opts_list(arg3, arg1, &(ctx->hsstart), &(ctx->hsend))) {
 	goto badarg;
     }
-    if (bfs.hsend == 0) {
-	BIF_RET(do_match_not_found_result(p, arg1, &bfs));
+    if (ctx->hsend == 0) {
+	result = do_match_not_found_result(p, arg1, &ctx);
+	BIF_RET(result);
     }
-    if (is_tuple(arg2)) {
-	tp = tuple_val(arg2);
-	if (arityval(*tp) != 2 || is_not_atom(tp[1])) {
-	    goto badarg;
-	}
-	if (((tp[1] != am_bm) && (tp[1] != am_ac)) ||
-	    !is_internal_magic_ref(tp[2])) {
-	    goto badarg;
-	}
-	bfs.type = tp[1];
-	bin = erts_magic_ref2bin(tp[2]);
-	if (bfs.type == am_bm &&
-	    ERTS_MAGIC_BIN_DESTRUCTOR(bin) != cleanup_my_data_bm) {
-	    goto badarg;
-	}
-	if (bfs.type == am_ac &&
-	    ERTS_MAGIC_BIN_DESTRUCTOR(bin) != cleanup_my_data_ac) {
-	    goto badarg;
-	}
-	bin_term = tp[2];
-    } else if (do_binary_match_compile(arg2, &(bfs.type), &bin)) {
+    if (maybe_binary_match_compile(ctx, arg2, &pat_bin) != BF_OK) {
 	goto badarg;
     }
-    bfs.not_found_result = &do_match_not_found_result;
-    bfs.single_result = &do_match_single_result;
-    bfs.global_result = &do_match_global_result;
-    runres = do_binary_find(p, arg1, &bfs, bin, NIL, &result);
-    if (runres == DO_BIN_MATCH_RESTART && bin_term == NIL) {
-	Eterm *hp = HAlloc(p, ERTS_MAGIC_REF_THING_SIZE);
-	bin_term = erts_mk_magic_ref(&hp, &MSO(p), bin);
-    } else if (bin_term == NIL) {
-	erts_bin_free(bin);
+    bf_context_init(ctx, do_match_not_found_result, do_match_single_result,
+		    do_match_global_result, pat_bin);
+    runres = do_binary_find(p, arg1, &ctx, pat_bin, NULL, &result);
+    if (runres == BF_OK && ctx->pat_term == THE_NON_VALUE) {
+	erts_bin_free(pat_bin);
     }
     switch (runres) {
-    case DO_BIN_MATCH_OK:
+    case BF_OK:
 	BIF_RET(result);
-    case DO_BIN_MATCH_RESTART:
-	BUMP_ALL_REDS(p);
-	BIF_TRAP3(&binary_find_trap_export, p, arg1, result, bin_term);
+    case BF_RESTART:
+	ASSERT(result == THE_NON_VALUE && ctx->trap_term != result && ctx->pat_term != result);
+	BIF_TRAP3(&binary_find_trap_export, p, arg1, ctx->trap_term, ctx->pat_term);
     default:
 	goto badarg;
     }
- badarg:
-    BIF_ERROR(p,BADARG);
+badarg:
+    BIF_ERROR(p, BADARG);
 }
 
 BIF_RETTYPE binary_match_2(BIF_ALIST_2)
@@ -1471,76 +1512,52 @@ BIF_RETTYPE binary_match_3(BIF_ALIST_3)
 
 BIF_RETTYPE binary_matches_2(BIF_ALIST_2)
 {
-    return binary_match(BIF_P, BIF_ARG_1, BIF_ARG_2, THE_NON_VALUE, BINARY_FIND_ALL);
+    return binary_match(BIF_P, BIF_ARG_1, BIF_ARG_2, THE_NON_VALUE, BF_FLAG_GLOBAL);
 }
 
 BIF_RETTYPE binary_matches_3(BIF_ALIST_3)
 {
-    return binary_match(BIF_P, BIF_ARG_1, BIF_ARG_2, BIF_ARG_3, BINARY_FIND_ALL);
+    return binary_match(BIF_P, BIF_ARG_1, BIF_ARG_2, BIF_ARG_3, BF_FLAG_GLOBAL);
 }
 
 static BIF_RETTYPE
 binary_split(Process *p, Eterm arg1, Eterm arg2, Eterm arg3)
 {
-    BinaryFindState bfs;
-    Eterm *tp;
-    Binary *bin;
-    Eterm bin_term = NIL;
+    BinaryFindContext c_buff;
+    BinaryFindContext *ctx = &c_buff;
+    Binary *pat_bin;
     int runres;
     Eterm result;
 
-    if (is_not_binary(arg1)) {
+    if (is_not_binary(arg1) || binary_bitsize(arg1) != 0) {
 	goto badarg;
     }
-    if (parse_split_opts_list(arg3, arg1, &(bfs.hsstart), &(bfs.hsend), &(bfs.flags))) {
+    if (parse_split_opts_list(arg3, arg1, &(ctx->hsstart), &(ctx->hsend), &(ctx->flags))) {
 	goto badarg;
     }
-    if (bfs.hsend == 0) {
-	result = do_split_not_found_result(p, arg1, &bfs);
+    if (ctx->hsend == 0) {
+	result = do_split_not_found_result(p, arg1, &ctx);
 	BIF_RET(result);
     }
-    if (is_tuple(arg2)) {
-	tp = tuple_val(arg2);
-	if (arityval(*tp) != 2 || is_not_atom(tp[1])) {
-	    goto badarg;
-	}
-	if (((tp[1] != am_bm) && (tp[1] != am_ac)) ||
-	    !is_internal_magic_ref(tp[2])) {
-	    goto badarg;
-	}
-	bfs.type = tp[1];
-	bin = erts_magic_ref2bin(tp[2]);
-	if (bfs.type == am_bm &&
-	    ERTS_MAGIC_BIN_DESTRUCTOR(bin) != cleanup_my_data_bm) {
-	    goto badarg;
-	}
-	if (bfs.type == am_ac &&
-	    ERTS_MAGIC_BIN_DESTRUCTOR(bin) != cleanup_my_data_ac) {
-	    goto badarg;
-	}
-	bin_term = tp[2];
-    } else if (do_binary_match_compile(arg2, &(bfs.type), &bin)) {
+    if (maybe_binary_match_compile(ctx, arg2, &pat_bin) != BF_OK) {
 	goto badarg;
     }
-    bfs.not_found_result = &do_split_not_found_result;
-    bfs.single_result = &do_split_single_result;
-    bfs.global_result = &do_split_global_result;
-    runres = do_binary_find(p, arg1, &bfs, bin, NIL, &result);
-    if (runres == DO_BIN_MATCH_RESTART && bin_term == NIL) {
-	Eterm *hp = HAlloc(p, ERTS_MAGIC_REF_THING_SIZE);
-	bin_term = erts_mk_magic_ref(&hp, &MSO(p), bin);
-    } else if (bin_term == NIL) {
-	erts_bin_free(bin);
-    }
-    switch(runres) {
-    case DO_BIN_MATCH_OK:
+    bf_context_init(ctx, do_split_not_found_result, do_split_single_result,
+		    do_split_global_result, pat_bin);
+    runres = do_binary_find(p, arg1, &ctx, pat_bin, NULL, &result);
+    if (runres == BF_OK && ctx->pat_term == THE_NON_VALUE) {
+	erts_bin_free(pat_bin);
+    }
+    switch (runres) {
+    case BF_OK:
 	BIF_RET(result);
-    case DO_BIN_MATCH_RESTART:
-	BIF_TRAP3(&binary_find_trap_export, p, arg1, result, bin_term);
+    case BF_RESTART:
+	ASSERT(result == THE_NON_VALUE && ctx->trap_term != result && ctx->pat_term != result);
+	BIF_TRAP3(&binary_find_trap_export, p, arg1, ctx->trap_term, ctx->pat_term);
     default:
 	goto badarg;
     }
- badarg:
+badarg:
     BIF_ERROR(p, BADARG);
 }
 
@@ -1554,72 +1571,117 @@ BIF_RETTYPE binary_split_3(BIF_ALIST_3)
     return binary_split(BIF_P, BIF_ARG_1, BIF_ARG_2, BIF_ARG_3);
 }
 
-static Eterm do_match_not_found_result(Process *p, Eterm subject, BinaryFindState *bfs)
+static Eterm do_match_not_found_result(Process *p, Eterm subject, BinaryFindContext **ctxp)
 {
-    if (bfs->flags & BINARY_FIND_ALL) {
+    if ((*ctxp)->flags & BF_FLAG_GLOBAL) {
 	return NIL;
     } else {
 	return am_nomatch;
     }
 }
 
-static Eterm do_match_single_result(Process *p, Eterm subject, BinaryFindState *bfs,
-				    Sint pos, Sint len)
+static Eterm do_match_single_result(Process *p, Eterm subject, BinaryFindContext **ctxp)
 {
+    BinaryFindContext *ctx = (*ctxp);
+    BinaryFindFirstContext *ff = &(ctx->u.ff);
     Eterm erlen;
     Eterm *hp;
     Eterm ret;
 
-    erlen = erts_make_integer((Uint)(len), p);
-    ret = erts_make_integer(pos, p);
+    erlen = erts_make_integer((Uint)(ff->len), p);
+    ret = erts_make_integer(ff->pos, p);
     hp = HAlloc(p, 3);
     ret = TUPLE2(hp, ret, erlen);
 
     return ret;
 }
 
-static Eterm do_match_global_result(Process *p, Eterm subject, BinaryFindState *bfs,
-				    FindallData *fad, Uint fad_sz)
+static Eterm do_match_global_result(Process *p, Eterm subject, BinaryFindContext **ctxp)
 {
-    Sint i;
+    BinaryFindContext *ctx = (*ctxp);
+    BinaryFindAllContext *fa = &(ctx->u.fa);
+    FindallData *fad;
     Eterm tpl;
-    Eterm *hp;
-    Eterm ret;
+    Sint i;
+    register Uint reds = ctx->reds;
 
-    for (i = 0; i < fad_sz; ++i) {
-	fad[i].epos = erts_make_integer(fad[i].pos, p);
-	fad[i].elen = erts_make_integer(fad[i].len, p);
+    if (ctx->state == BFSearch) {
+	if (ctx->pat_type == am_ac) {
+	    fa->data = fa->d.ac.out;
+	    fa->size = fa->d.ac.m;
+	} else {
+	    fa->data = fa->d.bm.out;
+	    fa->size = fa->d.bm.m;
+	}
+	fa->tail = fa->size - 1;
+	fa->head = 0;
+	fa->end_pos = 0;
+	fa->term = NIL;
+	if (ctx->exported == 0 && ((fa->size * 2) >= reds)) {
+	    ctx = bf_context_export(p, ctx);
+	    *ctxp = ctx;
+	    fa = &(ctx->u.fa);
+	}
+	erts_factory_proc_prealloc_init(&(fa->factory), p, fa->size * (3 + 2));
+	ctx->state = BFResult;
+    }
+
+    fad = fa->data;
+
+    if (fa->end_pos == 0) {
+	for (i = fa->head; i < fa->size; ++i) {
+	    if (--reds == 0) {
+		ASSERT(ctx->exported == 1);
+		fa->head = i;
+		ctx->reds = reds;
+		return THE_NON_VALUE;
+	    }
+	    fad[i].epos = erts_make_integer(fad[i].pos, p);
+	    fad[i].elen = erts_make_integer(fad[i].len, p);
+	}
+	fa->end_pos = 1;
+	fa->head = fa->tail;
     }
-    hp = HAlloc(p, fad_sz * (3 + 2));
-    ret = NIL;
-    for (i = fad_sz - 1; i >= 0; --i) {
-	tpl = TUPLE2(hp, fad[i].epos, fad[i].elen);
-	hp += 3;
-	ret = CONS(hp, tpl, ret);
-	hp += 2;
+
+    for (i = fa->head; i >= 0; --i) {
+	if (--reds == 0) {
+	    ASSERT(ctx->exported == 1);
+	    fa->head = i;
+	    ctx->reds = reds;
+	    return THE_NON_VALUE;
+	}
+	tpl = TUPLE2(fa->factory.hp, fad[i].epos, fad[i].elen);
+	fa->factory.hp += 3;
+	fa->term = CONS(fa->factory.hp, tpl, fa->term);
+	fa->factory.hp += 2;
     }
+    ctx->reds = reds;
+    erts_factory_close(&(fa->factory));
 
-    return ret;
+    return fa->term;
 }
 
-static Eterm do_split_not_found_result(Process *p, Eterm subject, BinaryFindState *bfs)
+static Eterm do_split_not_found_result(Process *p, Eterm subject, BinaryFindContext **ctxp)
 {
+    BinaryFindContext *ctx = (*ctxp);
     Eterm *hp;
     Eterm ret;
 
-    if (bfs->flags & (BINARY_SPLIT_TRIM | BINARY_SPLIT_TRIM_ALL)
+    if (ctx->flags & (BF_FLAG_SPLIT_TRIM | BF_FLAG_SPLIT_TRIM_ALL)
         && binary_size(subject) == 0) {
-        return NIL;
+	return NIL;
     }
     hp = HAlloc(p, 2);
     ret = CONS(hp, subject, NIL);
-
     return ret;
 }
 
-static Eterm do_split_single_result(Process *p, Eterm subject, BinaryFindState *bfs,
-				    Sint pos, Sint len)
+static Eterm do_split_single_result(Process *p, Eterm subject, BinaryFindContext **ctxp)
 {
+    BinaryFindContext *ctx = (*ctxp);
+    BinaryFindFirstContext *ff = &(ctx->u.ff);
+    Sint pos;
+    Sint len;
     size_t orig_size;
     Eterm orig;
     Uint offset;
@@ -1630,9 +1692,12 @@ static Eterm do_split_single_result(Process *p, Eterm subject, BinaryFindState *
     Eterm *hp;
     Eterm ret;
 
+    pos = ff->pos;
+    len = ff->len;
+
     orig_size = binary_size(subject);
 
-    if ((bfs->flags & (BINARY_SPLIT_TRIM | BINARY_SPLIT_TRIM_ALL)) &&
+    if ((ctx->flags & (BF_FLAG_SPLIT_TRIM | BF_FLAG_SPLIT_TRIM_ALL)) &&
 	(orig_size - pos - len) == 0) {
 	if (pos == 0) {
 	    ret = NIL;
@@ -1653,7 +1718,7 @@ static Eterm do_split_single_result(Process *p, Eterm subject, BinaryFindState *
 	    hp += 2;
 	}
     } else {
-	if ((bfs->flags & BINARY_SPLIT_TRIM_ALL) && (pos == 0)) {
+	if ((ctx->flags & BF_FLAG_SPLIT_TRIM_ALL) && (pos == 0)) {
 	    hp = HAlloc(p, 1 * (ERL_SUB_BIN_SIZE + 2));
 	    ERTS_GET_REAL_BIN(subject, orig, offset, bit_offset, bit_size);
 	    sb1 = NULL;
@@ -1691,39 +1756,60 @@ static Eterm do_split_single_result(Process *p, Eterm subject, BinaryFindState *
     return ret;
 }
 
-static Eterm do_split_global_result(Process *p, Eterm subject, BinaryFindState *bfs,
-				    FindallData *fad, Uint fad_sz)
+static Eterm do_split_global_result(Process *p, Eterm subject, BinaryFindContext **ctxp)
 {
-    size_t orig_size;
+    BinaryFindContext *ctx = (*ctxp);
+    BinaryFindAllContext *fa = &(ctx->u.fa);
+    FindallData *fad;
     Eterm orig;
+    size_t orig_size;
     Uint offset;
     Uint bit_offset;
     Uint bit_size;
     ErlSubBin *sb;
+    Uint do_trim;
     Sint i;
-    Sint tail;
-    Uint list_size;
-    Uint end_pos;
-    Uint do_trim = bfs->flags & (BINARY_SPLIT_TRIM | BINARY_SPLIT_TRIM_ALL);
-    Eterm *hp;
-    Eterm *hendp;
-    Eterm ret;
+    register Uint reds = ctx->reds;
 
-    tail = fad_sz - 1;
-    list_size = fad_sz + 1;
-    orig_size = binary_size(subject);
-    end_pos = (Uint)(orig_size);
+    if (ctx->state == BFSearch) {
+	if (ctx->pat_type == am_ac) {
+	    fa->data = fa->d.ac.out;
+	    fa->size = fa->d.ac.m;
+	} else {
+	    fa->data = fa->d.bm.out;
+	    fa->size = fa->d.bm.m;
+	}
+	fa->tail = fa->size - 1;
+	fa->head = fa->tail;
+	orig_size = binary_size(subject);
+	fa->end_pos = (Uint)(orig_size);
+	fa->term = NIL;
+	if (ctx->exported == 0 && ((fa->head + 1) >= reds)) {
+	    ctx = bf_context_export(p, ctx);
+	    *ctxp = ctx;
+	    fa = &(ctx->u.fa);
+	}
+	erts_factory_proc_prealloc_init(&(fa->factory), p, (fa->size + 1) * (ERL_SUB_BIN_SIZE + 2));
+	ctx->state = BFResult;
+    }
 
-    hp = HAlloc(p, list_size * (ERL_SUB_BIN_SIZE + 2));
-    hendp = hp + list_size * (ERL_SUB_BIN_SIZE + 2);
     ERTS_GET_REAL_BIN(subject, orig, offset, bit_offset, bit_size);
     ASSERT(bit_size == 0);
+    fad = fa->data;
+    do_trim = ctx->flags & (BF_FLAG_SPLIT_TRIM | BF_FLAG_SPLIT_TRIM_ALL);
 
-    ret = NIL;
-
-    for (i = tail; i >= 0; --i) {
-	sb = (ErlSubBin *)(hp);
-	sb->size = end_pos - (fad[i].pos + fad[i].len);
+    for (i = fa->head; i >= 0; --i) {
+	if (--reds == 0) {
+	    ASSERT(ctx->exported == 1);
+	    fa->head = i;
+	    ctx->reds = reds;
+	    if (!do_trim && (ctx->flags & BF_FLAG_SPLIT_TRIM)) {
+		ctx->flags &= ~BF_FLAG_SPLIT_TRIM;
+	    }
+	    return THE_NON_VALUE;
+	}
+	sb = (ErlSubBin *)(fa->factory.hp);
+	sb->size = fa->end_pos - (fad[i].pos + fad[i].len);
 	if (!(sb->size == 0 && do_trim)) {
 	    sb->thing_word = HEADER_SUB_BIN;
 	    sb->offs = offset + fad[i].pos + fad[i].len;
@@ -1731,15 +1817,18 @@ static Eterm do_split_global_result(Process *p, Eterm subject, BinaryFindState *
 	    sb->bitoffs = bit_offset;
 	    sb->bitsize = 0;
 	    sb->is_writable = 0;
-	    hp += ERL_SUB_BIN_SIZE;
-	    ret = CONS(hp, make_binary(sb), ret);
-	    hp += 2;
-	    do_trim &= ~BINARY_SPLIT_TRIM;
+	    fa->factory.hp += ERL_SUB_BIN_SIZE;
+	    fa->term = CONS(fa->factory.hp, make_binary(sb), fa->term);
+	    fa->factory.hp += 2;
+	    do_trim &= ~BF_FLAG_SPLIT_TRIM;
 	}
-	end_pos = fad[i].pos;
+	fa->end_pos = fad[i].pos;
     }
 
-    sb = (ErlSubBin *)(hp);
+    fa->head = i;
+    ctx->reds = reds;
+
+    sb = (ErlSubBin *)(fa->factory.hp);
     sb->size = fad[0].pos;
     if (!(sb->size == 0 && do_trim)) {
 	sb->thing_word = HEADER_SUB_BIN;
@@ -1748,26 +1837,31 @@ static Eterm do_split_global_result(Process *p, Eterm subject, BinaryFindState *
 	sb->bitoffs = bit_offset;
 	sb->bitsize = 0;
 	sb->is_writable = 0;
-	hp += ERL_SUB_BIN_SIZE;
-	ret = CONS(hp, make_binary(sb), ret);
-	hp += 2;
+	fa->factory.hp += ERL_SUB_BIN_SIZE;
+	fa->term = CONS(fa->factory.hp, make_binary(sb), fa->term);
+	fa->factory.hp += 2;
     }
-    HRelease(p, hendp, hp);
-    return ret;
+    erts_factory_close(&(fa->factory));
+
+    return fa->term;
 }
 
 static BIF_RETTYPE binary_find_trap(BIF_ALIST_3)
 {
     int runres;
     Eterm result;
-    Binary *bin = erts_magic_ref2bin(BIF_ARG_3);
-
-    runres = do_binary_find(BIF_P, BIF_ARG_1, NULL, bin, BIF_ARG_2, &result);
-    if (runres == DO_BIN_MATCH_OK) {
+    Binary *ctx_bin = erts_magic_ref2bin(BIF_ARG_2);
+    Binary *pat_bin = erts_magic_ref2bin(BIF_ARG_3);
+    BinaryFindContext *ctx = NULL;
+
+    ASSERT(ERTS_MAGIC_BIN_DESTRUCTOR(ctx_bin) == bf_context_destructor);
+    runres = do_binary_find(BIF_P, BIF_ARG_1, &ctx, pat_bin, ctx_bin, &result);
+    if (runres == BF_OK) {
+	ASSERT(result != THE_NON_VALUE);
 	BIF_RET(result);
     } else {
-	BUMP_ALL_REDS(BIF_P);
-	BIF_TRAP3(&binary_find_trap_export, BIF_P, BIF_ARG_1, result, BIF_ARG_3);
+	ASSERT(result == THE_NON_VALUE && ctx->trap_term != result && ctx->pat_term != result);
+	BIF_TRAP3(&binary_find_trap_export, BIF_P, BIF_ARG_1, BIF_ARG_2, BIF_ARG_3);
     }
 }
 
diff --git a/erts/emulator/beam/erl_bif_ddll.c b/erts/emulator/beam/erl_bif_ddll.c
index e9bfb39035..f673ef3194 100644
--- a/erts/emulator/beam/erl_bif_ddll.c
+++ b/erts/emulator/beam/erl_bif_ddll.c
@@ -50,13 +50,6 @@
 #include "dtrace-wrapper.h"
 #include "lttng-wrapper.h"
 
-#ifdef ERTS_SMP
-#define DDLL_SMP 1
-#else
-#define DDLL_SMP 0
-#endif
-
-
 /*
  * Local types
  */
@@ -107,18 +100,18 @@ static void dereference_all_processes(DE_Handle *dh);
 static void restore_process_references(DE_Handle *dh);
 static void ddll_no_more_references(void *vdh);
 
-#define lock_drv_list() erts_smp_rwmtx_rwlock(&erts_driver_list_lock)
-#define unlock_drv_list() erts_smp_rwmtx_rwunlock(&erts_driver_list_lock)
+#define lock_drv_list() erts_rwmtx_rwlock(&erts_driver_list_lock)
+#define unlock_drv_list() erts_rwmtx_rwunlock(&erts_driver_list_lock)
 #define assert_drv_list_locked() \
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_rwmtx_is_rwlocked(&erts_driver_list_lock) \
-		       || erts_smp_lc_rwmtx_is_rlocked(&erts_driver_list_lock))
+    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(&erts_driver_list_lock) \
+		       || erts_lc_rwmtx_is_rlocked(&erts_driver_list_lock))
 #define assert_drv_list_rwlocked() \
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_rwmtx_is_rwlocked(&erts_driver_list_lock))
+    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(&erts_driver_list_lock))
 #define assert_drv_list_rlocked() \
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_rwmtx_is_rlocked(&erts_driver_list_lock))
+    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rlocked(&erts_driver_list_lock))
 #define assert_drv_list_not_locked() \
-    ERTS_SMP_LC_ASSERT(!erts_smp_lc_rwmtx_is_rwlocked(&erts_driver_list_lock) \
-		       && !erts_smp_lc_rwmtx_is_rlocked(&erts_driver_list_lock))
+    ERTS_LC_ASSERT(!erts_lc_rwmtx_is_rwlocked(&erts_driver_list_lock) \
+		       && !erts_lc_rwmtx_is_rlocked(&erts_driver_list_lock))
 
 
 #define FREE_PORT_FLAGS (ERTS_PORT_SFLGS_DEAD & (~ERTS_PORT_SFLG_INITIALIZING))
@@ -134,13 +127,13 @@ kill_ports_driver_unloaded(DE_Handle *dh)
 	if (!prt)
 	    continue;
 
-	ERTS_SMP_DATA_DEPENDENCY_READ_MEMORY_BARRIER;
+	ERTS_THR_DATA_DEPENDENCY_READ_MEMORY_BARRIER;
 
 	state = erts_atomic32_read_nob(&prt->state);
 	if (state & FREE_PORT_FLAGS)
 	    continue;
 
-	erts_smp_port_lock(prt);
+	erts_port_lock(prt);
 
 	state = erts_atomic32_read_nob(&prt->state);
 	if (!(state & ERTS_PORT_SFLGS_DEAD) && prt->drv_ptr->handle == dh)
@@ -280,10 +273,8 @@ BIF_RETTYPE erl_ddll_try_load_3(BIF_ALIST_3)
     path[path_len++] = '/';
     sys_strcpy(path+path_len,name);
 
-#if DDLL_SMP
-    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
     lock_drv_list();
-#endif
     if ((drv = lookup_driver(name)) != NULL) {
 	if (drv->handle == NULL) {
 	    /* static_driver */
@@ -404,24 +395,18 @@ BIF_RETTYPE erl_ddll_try_load_3(BIF_ALIST_3)
 	erts_ddll_reference_driver(dh);
 	ASSERT(dh->status == ERL_DE_RELOAD);
 	dh->status = ERL_DE_FORCE_RELOAD;
-#if DDLL_SMP
 	unlock_drv_list();
-#endif
 	kill_ports_driver_unloaded(dh);
 	/* Dereference, eventually causing driver destruction */
-#if DDLL_SMP
 	lock_drv_list(); 
-#endif
 	erts_ddll_dereference_driver(dh);
     } 
 
-#if DDLL_SMP
     erts_ddll_reference_driver(dh);
     unlock_drv_list();
-    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
     lock_drv_list();
     erts_ddll_dereference_driver(dh);
-#endif
 
     BIF_P->flags |= F_USING_DDLL;
     if (monitor) {
@@ -432,18 +417,14 @@ BIF_RETTYPE erl_ddll_try_load_3(BIF_ALIST_3)
 	hp = HAlloc(BIF_P, 3);
 	t = TUPLE2(hp, am_ok, ok_term);
     }
-#if DDLL_SMP
     unlock_drv_list();
-#endif
     erts_free(ERTS_ALC_T_DDLL_TMP_BUF, (void *) path);
     erts_free(ERTS_ALC_T_DDLL_TMP_BUF, (void *) name);
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(BIF_P));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(BIF_P));
     BIF_RET(t);
  soft_error:
-#if DDLL_SMP
     unlock_drv_list();
-    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
-#endif
+    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
     if (do_build_load_error) {
 	soft_error_term = build_load_error(BIF_P, build_this_load_error);
     }
@@ -452,11 +433,11 @@ BIF_RETTYPE erl_ddll_try_load_3(BIF_ALIST_3)
     t = TUPLE2(hp, am_error, soft_error_term);
     erts_free(ERTS_ALC_T_DDLL_TMP_BUF, (void *) path);
     erts_free(ERTS_ALC_T_DDLL_TMP_BUF, (void *) name);
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(BIF_P));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(BIF_P));
     BIF_RET(t);
  error:
     assert_drv_list_not_locked();
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(BIF_P));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(BIF_P));
     if (path != NULL) {
 	erts_free(ERTS_ALC_T_DDLL_TMP_BUF, (void *) path);
     }
@@ -518,7 +499,7 @@ Eterm erl_ddll_try_unload_2(BIF_ALIST_2)
     Eterm l;
     int kill_ports = 0;
 
-    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
 
     for(l = options; is_list(l); l =  CDR(list_val(l))) {
 	Eterm opt = CAR(list_val(l));
@@ -551,9 +532,7 @@ Eterm erl_ddll_try_unload_2(BIF_ALIST_2)
 	goto error;
     }
 
-#if DDLL_SMP
     lock_drv_list();
-#endif
 
     if ((drv = lookup_driver(name)) == NULL) {
 	soft_error_term = am_not_loaded;
@@ -597,7 +576,7 @@ Eterm erl_ddll_try_unload_2(BIF_ALIST_2)
 	dh->reload_full_path = dh->reload_driver_name = NULL; 
 	dh->reload_flags = 0;
     } 
-    if (erts_smp_atomic32_read_nob(&dh->port_count) > 0) {
+    if (erts_atomic32_read_nob(&dh->port_count) > 0) {
 	++kill_ports;
     }
     dh->status = ERL_DE_UNLOAD;
@@ -608,23 +587,17 @@ done:
 	/* Avoid closing the driver by referencing it */
 	erts_ddll_reference_driver(dh);
 	dh->status = ERL_DE_FORCE_UNLOAD;
-#if DDLL_SMP
 	unlock_drv_list();
-#endif
 	kill_ports_driver_unloaded(dh);
-#if DDLL_SMP
 	lock_drv_list(); 
-#endif
 	erts_ddll_dereference_driver(dh);
     } 
 
-#if DDLL_SMP
     erts_ddll_reference_driver(dh);
     unlock_drv_list();
-    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
     lock_drv_list();
     erts_ddll_dereference_driver(dh);
-#endif
     erts_free(ERTS_ALC_T_DDLL_TMP_BUF, (void *) name);
     BIF_P->flags |= F_USING_DDLL;
     if (monitor > 0) {
@@ -638,17 +611,13 @@ done:
     if (kill_ports > 1) {
 	ERTS_BIF_CHK_EXITED(BIF_P); /* May be exited by port killing */
     }
-#if DDLL_SMP
     unlock_drv_list();
-#endif
     BIF_RET(t);
  
 soft_error:
-#if DDLL_SMP
     unlock_drv_list();
-#endif
     erts_free(ERTS_ALC_T_DDLL_TMP_BUF, (void *) name);
-    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
     hp = HAlloc(BIF_P, 3);
     t = TUPLE2(hp, am_error, soft_error_term);
     BIF_RET(t);
@@ -658,7 +627,7 @@ soft_error:
     if (name != NULL) {
 	erts_free(ERTS_ALC_T_DDLL_TMP_BUF, (void *) name);
     }
-    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
     BIF_ERROR(BIF_P, BADARG);
 }
 
@@ -697,9 +666,7 @@ BIF_RETTYPE erl_ddll_loaded_drivers_0(BIF_ALIST_0)
     int need = 3;
     Eterm res = NIL;
     erts_driver_t *drv;
-#if DDLL_SMP
     lock_drv_list();
-#endif
     for (drv = driver_list; drv; drv = drv->next) {
 	need += sys_strlen(drv->name)*2+2;
     }
@@ -712,9 +679,7 @@ BIF_RETTYPE erl_ddll_loaded_drivers_0(BIF_ALIST_0)
     }
     res = TUPLE2(hp,am_ok,res);
     /* hp += 3 */
-#if DDLL_SMP
     unlock_drv_list();
-#endif
     BIF_RET(res);
 }
 
@@ -736,9 +701,7 @@ BIF_RETTYPE erl_ddll_info_2(BIF_ALIST_2)
     Eterm *hp;
     int i;
     Uint filter;
-#if DDLL_SMP
     int have_lock = 0;
-#endif
 
     if ((name = pick_list_or_atom(name_term)) == NULL) {
 	goto error;
@@ -748,10 +711,8 @@ BIF_RETTYPE erl_ddll_info_2(BIF_ALIST_2)
 	goto error;
     }
 
-#if DDLL_SMP 
     lock_drv_list();
     have_lock = 1;
-#endif
     if ((drv = lookup_driver(name)) == NULL) {
 	goto error;
     }
@@ -781,7 +742,7 @@ BIF_RETTYPE erl_ddll_info_2(BIF_ALIST_2)
 	} else if (drv->handle->status == ERL_DE_PERMANENT) {
 	    res = am_permanent;
 	} else {
-	    res = make_small(erts_smp_atomic32_read_nob(&drv->handle->port_count));
+	    res = make_small(erts_atomic32_read_nob(&drv->handle->port_count));
 	}
 	goto done;
     case am_linked_in_driver:
@@ -827,9 +788,7 @@ BIF_RETTYPE erl_ddll_info_2(BIF_ALIST_2)
 	hp += 2;
     }    
  done:    
-#if DDLL_SMP
     unlock_drv_list();
-#endif
     if (pei)
 	erts_free(ERTS_ALC_T_DDLL_TMP_BUF, pei);
     erts_free(ERTS_ALC_T_DDLL_TMP_BUF, (void *) name);
@@ -838,11 +797,9 @@ BIF_RETTYPE erl_ddll_info_2(BIF_ALIST_2)
     if (name != NULL) {
 	erts_free(ERTS_ALC_T_DDLL_TMP_BUF, (void *) name);
     }
-#if DDLL_SMP
     if (have_lock) {
 	unlock_drv_list();
     }
-#endif
     BIF_ERROR(p,BADARG);
 }
 
@@ -899,13 +856,9 @@ BIF_RETTYPE erl_ddll_format_error_int_1(BIF_ALIST_1)
 	if (errdesc_to_code(code_term,&errint) != 0) {
 	    goto error;
 	}
-#if DDLL_SMP 
 	lock_drv_list();
-#endif
 	errstring = erts_ddll_error(errint);
-#if DDLL_SMP
 	unlock_drv_list();
-#endif
 	break;
     }
     if (errstring == NULL) {
@@ -968,7 +921,7 @@ Eterm erts_ddll_monitor_driver(Process *p,
 void erts_ddll_remove_monitor(Process *p, Eterm ref, ErtsProcLocks plocks)
 { 
     erts_driver_t *drv;
-    erts_smp_proc_unlock(p, plocks);
+    erts_proc_unlock(p, plocks);
     lock_drv_list();
     drv = driver_list;
     while (drv != NULL) {
@@ -993,7 +946,7 @@ void erts_ddll_remove_monitor(Process *p, Eterm ref, ErtsProcLocks plocks)
     }
  done:
     unlock_drv_list();
-    erts_smp_proc_lock(p, plocks);
+    erts_proc_lock(p, plocks);
 }
 
 /* 
@@ -1002,7 +955,7 @@ void erts_ddll_remove_monitor(Process *p, Eterm ref, ErtsProcLocks plocks)
 void erts_ddll_proc_dead(Process *p, ErtsProcLocks plocks) 
 {
     erts_driver_t *drv;
-    erts_smp_proc_unlock(p, plocks);
+    erts_proc_unlock(p, plocks);
     lock_drv_list();
     drv = driver_list;
     while (drv != NULL) {
@@ -1040,18 +993,14 @@ void erts_ddll_proc_dead(Process *p, ErtsProcLocks plocks)
 		dh->status = ERL_DE_UNLOAD;
 	    }
 	    if (!left
-		&& erts_smp_atomic32_read_nob(&drv->handle->port_count) > 0) {
+		&& erts_atomic32_read_nob(&drv->handle->port_count) > 0) {
 		if (kill_ports) {
 		    DE_Handle *dh = drv->handle;
 		    erts_ddll_reference_driver(dh);
 		    dh->status = ERL_DE_FORCE_UNLOAD;
-#if DDLL_SMP
 		    unlock_drv_list();
-#endif
 		    kill_ports_driver_unloaded(dh);
-#if DDLL_SMP
 		    lock_drv_list(); /* Needed for future list operations */
-#endif
 		    drv = drv->next; /* before allowing destruction */
 		    erts_ddll_dereference_driver(dh);
 		} else {
@@ -1065,7 +1014,7 @@ void erts_ddll_proc_dead(Process *p, ErtsProcLocks plocks)
 	}
     }
     unlock_drv_list();
-    erts_smp_proc_lock(p, plocks);
+    erts_proc_lock(p, plocks);
 }
 void erts_ddll_lock_driver(DE_Handle *dh, char *name)
 {
@@ -1093,41 +1042,41 @@ void erts_ddll_lock_driver(DE_Handle *dh, char *name)
 void erts_ddll_increment_port_count(DE_Handle *dh) 
 {
     assert_drv_list_locked();
-    erts_smp_atomic32_inc_nob(&dh->port_count);
+    erts_atomic32_inc_nob(&dh->port_count);
 }
 
 void erts_ddll_decrement_port_count(DE_Handle *dh)
 {
     assert_drv_list_locked();
 #ifdef DEBUG
-    ASSERT(erts_smp_atomic32_dec_read_nob(&dh->port_count) >= 0);
+    ASSERT(erts_atomic32_dec_read_nob(&dh->port_count) >= 0);
 #else
-    erts_smp_atomic32_dec_nob(&dh->port_count);
+    erts_atomic32_dec_nob(&dh->port_count);
 #endif
 }
 
 static void first_ddll_reference(DE_Handle *dh) 
 {
     assert_drv_list_rwlocked();
-    erts_smp_refc_init(&(dh->refc),1);
+    erts_refc_init(&(dh->refc),1);
 }
 
 void erts_ddll_reference_driver(DE_Handle *dh)
 {
     assert_drv_list_locked();
-    if (erts_smp_refc_inctest(&(dh->refc),1) == 1) {
-	erts_smp_refc_inc(&(dh->refc),2); /* add a reference for the scheduled operation */
+    if (erts_refc_inctest(&(dh->refc),1) == 1) {
+	erts_refc_inc(&(dh->refc),2); /* add a reference for the scheduled operation */
     }
 }
 
 void erts_ddll_reference_referenced_driver(DE_Handle *dh)
 {
-    erts_smp_refc_inc(&(dh->refc),2);
+    erts_refc_inc(&(dh->refc),2);
 }
 
 void erts_ddll_dereference_driver(DE_Handle *dh)
 {
-    if (erts_smp_refc_dectest(&(dh->refc),0) == 0) {
+    if (erts_refc_dectest(&(dh->refc),0) == 0) {
 	/* No lock here, but if the driver is referenced again,
 	   the scheduled deletion is added as a reference too, see above */
 	erts_schedule_misc_op(ddll_no_more_references, (void *) dh);
@@ -1150,11 +1099,11 @@ static void restore_process_references(DE_Handle *dh)
 {
     DE_ProcEntry *p;
     assert_drv_list_rwlocked();
-    ASSERT(erts_smp_refc_read(&(dh->refc),0) == 0);
+    ASSERT(erts_refc_read(&(dh->refc),0) == 0);
     for(p  = dh->procs;p != NULL; p = p->next) {
 	if (p->awaiting_status == ERL_DE_PROC_LOADED) {
 	    ASSERT(p->flags & ERL_DE_FL_DEREFERENCED);
-	    erts_smp_refc_inc(&(dh->refc),1);
+	    erts_refc_inc(&(dh->refc),1);
 	    p->flags &= ~ERL_DE_FL_DEREFERENCED;
 	}
     }
@@ -1176,9 +1125,9 @@ static void ddll_no_more_references(void *vdh)
 
     lock_drv_list();
 
-    x = erts_smp_refc_read(&(dh->refc),0);
+    x = erts_refc_read(&(dh->refc),0);
     if (x > 0) {
-	x = erts_smp_refc_dectest(&(dh->refc),0); /* delete the reference added for me */
+	x = erts_refc_dectest(&(dh->refc),0); /* delete the reference added for me */
     }
 
 
@@ -1281,10 +1230,8 @@ static Eterm notify_when_loaded(Process *p, Eterm name_term, char *name, ErtsPro
     Eterm immediate_type = NIL;
     erts_driver_t *drv;
 
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & plocks);
-#if DDLL_SMP 
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & plocks);
     lock_drv_list();
-#endif
     if ((drv = lookup_driver(name)) == NULL) {
 	immediate_tag = am_unloaded;
 	immediate_type = am_DOWN;
@@ -1314,20 +1261,14 @@ static Eterm notify_when_loaded(Process *p, Eterm name_term, char *name, ErtsPro
     }
     p->flags |= F_USING_DDLL;
     r = add_monitor(p, drv->handle, ERL_DE_PROC_AWAIT_LOAD);
-#if DDLL_SMP
     unlock_drv_list();
-#endif
     BIF_RET(r);
  immediate:
     r =  erts_make_ref(p);
-#if DDLL_SMP 
-    erts_smp_proc_unlock(p, plocks);
-#endif
+    erts_proc_unlock(p, plocks);
     notify_proc(p, r, name_term, immediate_type, immediate_tag, 0);
-#if DDLL_SMP
     unlock_drv_list();
-    erts_smp_proc_lock(p, plocks);
-#endif
+    erts_proc_lock(p, plocks);
     BIF_RET(r);
 }
 
@@ -1338,10 +1279,8 @@ static Eterm notify_when_unloaded(Process *p, Eterm name_term, char *name, ErtsP
     Eterm immediate_type = NIL;
     erts_driver_t *drv;
 
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & plocks);
-#if DDLL_SMP 
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & plocks);
     lock_drv_list();
-#endif
     if ((drv = lookup_driver(name)) == NULL) {
 	immediate_tag = am_unloaded;
 	immediate_type = am_DOWN;
@@ -1355,20 +1294,14 @@ static Eterm notify_when_unloaded(Process *p, Eterm name_term, char *name, ErtsP
 
     p->flags |= F_USING_DDLL;
     r = add_monitor(p, drv->handle, flag);
-#if DDLL_SMP
     unlock_drv_list();
-#endif
     BIF_RET(r);
  immediate:
     r =  erts_make_ref(p);
-#if DDLL_SMP 
-    erts_smp_proc_unlock(p, plocks);
-#endif
+    erts_proc_unlock(p, plocks);
     notify_proc(p, r, name_term, immediate_type, immediate_tag, 0);
-#if DDLL_SMP
     unlock_drv_list();
-    erts_smp_proc_lock(p, plocks);
-#endif
+    erts_proc_lock(p, plocks);
     BIF_RET(r);
 }
 
@@ -1572,8 +1505,8 @@ static int do_load_driver_entry(DE_Handle *dh, char *path, char *name)
 	res = ERL_DE_LOAD_ERROR_BAD_NAME;
 	goto error;
     }
-    erts_smp_atomic_init_nob(&(dh->refc), (erts_aint_t) 0);
-    erts_smp_atomic32_init_nob(&dh->port_count, 0);
+    erts_atomic_init_nob(&(dh->refc), (erts_aint_t) 0);
+    erts_atomic32_init_nob(&dh->port_count, 0);
     dh->full_path = erts_alloc(ERTS_ALC_T_DDLL_HANDLE, sys_strlen(path) + 1);
     sys_strcpy(dh->full_path, path);
     dh->flags = 0;
@@ -1644,8 +1577,8 @@ static int load_driver_entry(DE_Handle **dhp, char *path, char *name)
 
     dh->handle = NULL;
     dh->procs = NULL;
-    erts_smp_atomic32_init_nob(&dh->port_count, 0);
-    erts_smp_refc_init(&(dh->refc), (erts_aint_t) 0);
+    erts_atomic32_init_nob(&dh->port_count, 0);
+    erts_refc_init(&(dh->refc), (erts_aint_t) 0);
     dh->status = -1;
     dh->reload_full_path = NULL;
     dh->reload_driver_name = NULL;
@@ -1683,7 +1616,7 @@ static int reload_driver_entry(DE_Handle *dh)
     dh->reload_full_path = NULL;
     dh->reload_driver_name = NULL;
 
-    ASSERT(erts_smp_refc_read(&(dh->refc),0) == 0);
+    ASSERT(erts_refc_read(&(dh->refc),0) == 0);
     ASSERT(dh->full_path != NULL);
     erts_free(ERTS_ALC_T_DDLL_HANDLE, (void *) dh->full_path);
     dh->full_path = NULL;
@@ -1714,7 +1647,7 @@ static void notify_proc(Process *proc, Eterm ref, Eterm driver_name, Eterm type,
     ErtsMessage *mp;
     ErtsProcLocks rp_locks = 0;
     ErlOffHeap *ohp;
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     assert_drv_list_rwlocked();
     if (errcode != 0) {
@@ -1740,8 +1673,8 @@ static void notify_proc(Process *proc, Eterm ref, Eterm driver_name, Eterm type,
 	mess = TUPLE5(hp,type,r,am_driver,driver_name,tag);
     }
     erts_queue_message(proc, rp_locks, mp, mess, am_system);
-    erts_smp_proc_unlock(proc, rp_locks);
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    erts_proc_unlock(proc, rp_locks);
+    ERTS_CHK_NO_PROC_LOCKS;
 }
 
 static void notify_all(DE_Handle *dh, char *name, Uint awaiting, Eterm type, Eterm tag)
@@ -1813,7 +1746,7 @@ static Eterm build_load_error(Process *p, int code)
 {
     int need = load_error_need(code);
     Eterm *hp = NULL;
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(p));
     if (need) {
 	hp = HAlloc(p,need);
     }
diff --git a/erts/emulator/beam/erl_bif_info.c b/erts/emulator/beam/erl_bif_info.c
index 80adca0072..2f6f2c6e0a 100644
--- a/erts/emulator/beam/erl_bif_info.c
+++ b/erts/emulator/beam/erl_bif_info.c
@@ -46,6 +46,7 @@
 #include "erl_thr_progress.h"
 #include "erl_bif_unique.h"
 #include "erl_map.h"
+#include "erl_check_io.h"
 #define ERTS_PTAB_WANT_DEBUG_FUNCS__
 #include "erl_ptab.h"
 #include "erl_time.h"
@@ -88,24 +89,15 @@ static char erts_system_version[] = ("Erlang/OTP " ERLANG_OTP_RELEASE
 #ifdef ARCH_64
 				     " [64-bit]"
 #endif
-#ifdef ERTS_SMP
 				     " [smp:%beu:%beu]"
-#endif
-#ifdef USE_THREADS
-#if defined(ERTS_DIRTY_SCHEDULERS) && defined(ERTS_SMP)
 				     " [ds:%beu:%beu:%beu]"
-#endif
 #if defined(ERTS_DIRTY_SCHEDULERS_TEST)
 				     " [dirty-schedulers-TEST]"
 #endif
 				     " [async-threads:%d]"
-#endif
 #ifdef HIPE
 				     " [hipe]"
 #endif	
-#ifdef ERTS_ENABLE_KERNEL_POLL
-				     " [kernel-poll:%s]"
-#endif	
 #ifdef ET_DEBUG
 #if ET_DEBUG
 				     " [type-assertions]"
@@ -354,14 +346,12 @@ erts_print_system_version(fmtfn_t to, void *arg, Process *c_p)
     char *rc_str = "";
     char rc_buf[100];
     char *ov = otp_version;
-#ifdef ERTS_SMP
     Uint total, online, active;
     Uint dirty_cpu, dirty_cpu_onln, dirty_io;
 
     erts_schedulers_state(&total, &online, &active,
 			  &dirty_cpu, &dirty_cpu_onln, NULL,
 			  &dirty_io, NULL);
-#endif
     for (i = 0; i < sizeof(otp_version)-4; i++) {
 	if (ov[i] == '-' && ov[i+1] == 'r' && ov[i+2] == 'c')
 	    rc = atoi(&ov[i+3]);
@@ -376,18 +366,9 @@ erts_print_system_version(fmtfn_t to, void *arg, Process *c_p)
     }
     return erts_print(to, arg, erts_system_version,
 		      rc_str
-#ifdef ERTS_SMP
 		      , total, online
-#ifdef ERTS_DIRTY_SCHEDULERS
 		      , dirty_cpu, dirty_cpu_onln, dirty_io
-#endif
-#endif
-#ifdef USE_THREADS
 		      , erts_async_max_threads
-#endif
-#ifdef ERTS_ENABLE_KERNEL_POLL
-		      , erts_use_kernel_poll ? "true" : "false"
-#endif
 	);
 }
 
@@ -764,7 +745,6 @@ process_info_init(void)
 static ERTS_INLINE Process *
 pi_pid2proc(Process *c_p, Eterm pid, ErtsProcLocks info_locks)
 {
-#ifdef ERTS_SMP
     /*
      * If the main lock is needed, we use erts_pid2proc_not_running()
      * instead of erts_pid2proc() for two reasons:
@@ -782,7 +762,6 @@ pi_pid2proc(Process *c_p, Eterm pid, ErtsProcLocks info_locks)
 	return erts_pid2proc_not_running(c_p, ERTS_PROC_LOCK_MAIN,
 					 pid, info_locks);
     else
-#endif
 	return erts_pid2proc(c_p, ERTS_PROC_LOCK_MAIN,
 			     pid, info_locks);
 }
@@ -900,13 +879,13 @@ process_info_list(Process *c_p, Eterm pid, Eterm list, int always_wrap,
 	     * is being inspected...
 	     */
 	    ASSERT(locks & ERTS_PROC_LOCK_MAIN);
-	    ERTS_SMP_MSGQ_MV_INQ2PRIVQ(rp);
+	    ERTS_MSGQ_MV_INQ2PRIVQ(rp);
 	    locks &= ~ERTS_PROC_LOCK_MSGQ;
 	    unlock_locks |= ERTS_PROC_LOCK_MSGQ;
 	}
 
 	if (unlock_locks)
-	    erts_smp_proc_unlock(rp, unlock_locks);
+	    erts_proc_unlock(rp, unlock_locks);
 
     }
 
@@ -964,7 +943,7 @@ process_info_list(Process *c_p, Eterm pid, Eterm list, int always_wrap,
     if (c_p == rp)
 	locks &= ~ERTS_PROC_LOCK_MAIN;
     if (locks && rp)
-	erts_smp_proc_unlock(rp, locks);
+	erts_proc_unlock(rp, locks);
 
     if (res_elem_ix != &def_res_elem_ix_buf[0])
 	erts_free(ERTS_ALC_T_TMP, res_elem_ix);
@@ -1055,7 +1034,7 @@ BIF_RETTYPE process_info_2(BIF_ALIST_2)
 	ERTS_BIF_YIELD2(bif_export[BIF_process_info_2], BIF_P,
 			BIF_ARG_1, BIF_ARG_2);
     else if (rp != BIF_P && ERTS_PROC_PENDING_EXIT(rp)) {
-	erts_smp_proc_unlock(rp, info_locks|ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(rp, info_locks|ERTS_PROC_LOCK_STATUS);
 	ERTS_BIF_AWAIT_X_DATA_TRAP(BIF_P, BIF_ARG_1, am_undefined);
     }
     else {
@@ -1075,24 +1054,22 @@ BIF_RETTYPE process_info_2(BIF_ALIST_2)
 	     * is being inspected...
 	     */
 	    ASSERT(info_locks & ERTS_PROC_LOCK_MAIN);
-	    ERTS_SMP_MSGQ_MV_INQ2PRIVQ(rp);
+	    ERTS_MSGQ_MV_INQ2PRIVQ(rp);
 	    info_locks &= ~ERTS_PROC_LOCK_MSGQ;
 	    unlock_locks |= ERTS_PROC_LOCK_MSGQ;
 	}
 
 	if (unlock_locks)
-	    erts_smp_proc_unlock(rp, unlock_locks);
+	    erts_proc_unlock(rp, unlock_locks);
 
 	res = process_info_aux(BIF_P, rp, info_locks, pid, BIF_ARG_2, 0);
     }
     ASSERT(is_value(res));
 
-#ifdef ERTS_SMP
     if (BIF_P == rp)
 	info_locks &= ~ERTS_PROC_LOCK_MAIN;
     if (rp && info_locks)
-	erts_smp_proc_unlock(rp, info_locks);
-#endif
+	erts_proc_unlock(rp, info_locks);
 
     ASSERT(!(BIF_P->flags & F_P2PNR_RESCHED));
     BIF_RET(res);
@@ -1379,7 +1356,7 @@ process_info_aux(Process *BIF_P,
 	break;
 
     case am_trap_exit: {
-	erts_aint32_t state = erts_smp_atomic32_read_nob(&rp->state);
+	erts_aint32_t state = erts_atomic32_read_nob(&rp->state);
 	hp = HAlloc(BIF_P, 3);
 	if (state & ERTS_PSFLG_TRAP_EXIT)
 	    res = am_true;
@@ -2145,14 +2122,6 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	ASSERT(erts_compat_rel > 0);
 	BIF_RET(make_small(erts_compat_rel));
     } else if (BIF_ARG_1 == am_multi_scheduling) {
-#ifndef ERTS_SMP
-	BIF_RET(am_disabled);
-#else
-#ifndef ERTS_DIRTY_SCHEDULERS
-	if (erts_no_schedulers == 1)
-	    BIF_RET(am_disabled);
-	else
-#endif
 	{
 	    int msb = erts_is_multi_scheduling_blocked();
 	    BIF_RET(!msb
@@ -2161,7 +2130,6 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 		       ? am_blocked
 		       : am_blocked_normal));
 	}
-#endif
     } else if (BIF_ARG_1 == am_build_type) {
 #if defined(DEBUG)
 	ERTS_DECL_AM(debug);
@@ -2271,7 +2239,7 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	res = TUPLE2(hp, am_sequential_tracer, val);
 	BIF_RET(res);
     } else if (BIF_ARG_1 == am_garbage_collection){
-	Uint val = (Uint) erts_smp_atomic32_read_nob(&erts_max_gen_gcs);
+	Uint val = (Uint) erts_atomic32_read_nob(&erts_max_gen_gcs);
 	Eterm tup;
 	hp = HAlloc(BIF_P, 3+2 + 3+2 + 3+2 + 3+2);
 
@@ -2289,7 +2257,7 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 
 	BIF_RET(res);
     } else if (BIF_ARG_1 == am_fullsweep_after){
-	Uint val = (Uint) erts_smp_atomic32_read_nob(&erts_max_gen_gcs);
+	Uint val = (Uint) erts_atomic32_read_nob(&erts_max_gen_gcs);
 	hp = HAlloc(BIF_P, 3);
 	res = TUPLE2(hp, am_fullsweep_after, make_small(val));
 	BIF_RET(res);
@@ -2322,8 +2290,8 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	erts_dsprintf_buf_t *dsbufp = erts_create_info_dsbuf(0);
 
 	/* Need to be the only thread running... */
-	erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-	erts_smp_thr_progress_block();
+	erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_block();
 
 	if (BIF_ARG_1 == am_info)
 	    info(ERTS_PRINT_DSBUF, (void *) dsbufp);
@@ -2334,8 +2302,8 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	else
 	    distribution_info(ERTS_PRINT_DSBUF, (void *) dsbufp);
 
-	erts_smp_thr_progress_unblock();
-	erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_unblock();
+	erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 
 	ASSERT(dsbufp && dsbufp->str);
 	res = new_binary(BIF_P, (byte *) dsbufp->str, dsbufp->str_len);
@@ -2344,7 +2312,7 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
     } else if (ERTS_IS_ATOM_STR("dist_ctrl", BIF_ARG_1)) {
 	DistEntry *dep;
 	i = 0;
-        erts_smp_rwmtx_rlock(&erts_dist_table_rwmtx);
+        erts_rwmtx_rlock(&erts_dist_table_rwmtx);
 	for (dep = erts_visible_dist_entries; dep; dep = dep->next) 
 	    ++i;
 	for (dep = erts_hidden_dist_entries; dep; dep = dep->next)
@@ -2367,7 +2335,7 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	    res = CONS(hp, tpl, res);
 	    hp += 2;
 	}
-        erts_smp_rwmtx_runlock(&erts_dist_table_rwmtx);
+        erts_rwmtx_runlock(&erts_dist_table_rwmtx);
 	BIF_RET(res);
     } else if (BIF_ARG_1 == am_system_version) {
 	erts_dsprintf_buf_t *dsbufp = erts_create_tmp_dsbuf(0);
@@ -2393,16 +2361,10 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	BIF_RET(erts_allocator_options((void *) BIF_P));
     }
     else if (BIF_ARG_1 == am_thread_pool_size) {
-#ifdef USE_THREADS
 	extern int erts_async_max_threads;
-#endif
 	int n;
 	
-#ifdef USE_THREADS
 	n = erts_async_max_threads;
-#else
-	n = 0;
-#endif
 	BIF_RET(make_small(n));
     }
     else if (BIF_ARG_1 == am_alloc_util_allocators) {
@@ -2470,7 +2432,7 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 #endif
 
 	BIF_RET(res);
-#endif /* #ifndef ERTS_SMP */
+#endif /* #ifndef ERTS_OPCODE_COUNTER_SUPPORT */
     } else if (BIF_ARG_1 == am_wordsize) {
 	return make_small(sizeof(Eterm));
     } else if (BIF_ARG_1 == am_endian) {
@@ -2550,11 +2512,7 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	BIF_RET(res);
 #endif
     } else if (BIF_ARG_1 == am_threads) {
-#ifdef USE_THREADS
 	return am_true;
-#else
-	return am_false;
-#endif
     } else if (BIF_ARG_1 == am_creation) {
 	return make_small(erts_this_node->creation);
     } else if (BIF_ARG_1 == am_break_ignored) {
@@ -2613,11 +2571,7 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	hp = HAlloc(BIF_P, 2*n);
 	BIF_RET(buf_to_intlist(&hp, buf, n, NIL));
     } else if (ERTS_IS_ATOM_STR("smp_support", BIF_ARG_1)) {
-#ifdef ERTS_SMP
 	BIF_RET(am_true);
-#else
-	BIF_RET(am_false);
-#endif
     } else if (ERTS_IS_ATOM_STR("scheduler_bind_type", BIF_ARG_1)) {
 	BIF_RET(erts_bound_schedulers_term(BIF_P));
     } else if (ERTS_IS_ATOM_STR("scheduler_bindings", BIF_ARG_1)) {
@@ -2629,11 +2583,6 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	res = make_small(erts_no_schedulers);
 	BIF_RET(res);
     } else if (ERTS_IS_ATOM_STR("schedulers_state", BIF_ARG_1)) {
-#ifndef ERTS_SMP
-	Eterm *hp = HAlloc(BIF_P, 4);
-	res = TUPLE3(hp, make_small(1), make_small(1), make_small(1));
-	BIF_RET(res);
-#else
 	Eterm *hp;
 	Uint total, online, active;
 	erts_schedulers_state(&total, &online, &active,
@@ -2644,13 +2593,7 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 		     make_small(online),
 		     make_small(active));
 	BIF_RET(res);
-#endif
     } else if (ERTS_IS_ATOM_STR("schedulers_state", BIF_ARG_1)) {
-#ifndef ERTS_SMP
-	Eterm *hp = HAlloc(BIF_P, 4);
-	res = TUPLE3(hp, make_small(1), make_small(1), make_small(1));
-	BIF_RET(res);
-#else
 	Eterm *hp;
 	Uint total, online, active;
 	erts_schedulers_state(&total, &online, &active,
@@ -2661,19 +2604,7 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 		     make_small(online),
 		     make_small(active));
 	BIF_RET(res);
-#endif
     } else if (ERTS_IS_ATOM_STR("all_schedulers_state", BIF_ARG_1)) {
-#ifndef ERTS_SMP
-	Eterm *hp = HAlloc(BIF_P, 2+5);
-	res = CONS(hp+5,
-		   TUPLE4(hp,
-			  am_normal,
-			  make_small(1),
-			  make_small(1),
-			  make_small(1)),
-		   NIL);
-	BIF_RET(res);
-#else
 	Eterm *hp, tpl;
 	Uint sz, total, online, active,
 	    dirty_cpu_total, dirty_cpu_online, dirty_cpu_active,
@@ -2719,46 +2650,25 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	hp += 5;
 	res = CONS(hp, tpl, res);
 	BIF_RET(res);
-#endif
     } else if (ERTS_IS_ATOM_STR("schedulers_online", BIF_ARG_1)) {
-#ifndef ERTS_SMP
-	BIF_RET(make_small(1));
-#else
 	Uint online;
 	erts_schedulers_state(NULL, &online, NULL, NULL, NULL, NULL, NULL, NULL);
 	BIF_RET(make_small(online));
-#endif
     } else if (ERTS_IS_ATOM_STR("schedulers_active", BIF_ARG_1)) {
-#ifndef ERTS_SMP
-	BIF_RET(make_small(1));
-#else
 	Uint active;
 	erts_schedulers_state(NULL, NULL, &active, NULL, NULL, NULL, NULL, NULL);
 	BIF_RET(make_small(active));
-#endif
     } else if (ERTS_IS_ATOM_STR("dirty_cpu_schedulers", BIF_ARG_1)) {
 	Uint dirty_cpu;
-#ifdef ERTS_DIRTY_SCHEDULERS
 	erts_schedulers_state(NULL, NULL, NULL, &dirty_cpu, NULL, NULL, NULL, NULL);
-#else
-        dirty_cpu = 0;
-#endif
 	BIF_RET(make_small(dirty_cpu));
     } else if (ERTS_IS_ATOM_STR("dirty_cpu_schedulers_online", BIF_ARG_1)) {
 	Uint dirty_cpu_onln;
-#ifdef ERTS_DIRTY_SCHEDULERS
 	erts_schedulers_state(NULL, NULL, NULL, NULL, &dirty_cpu_onln, NULL, NULL, NULL);
-#else
-        dirty_cpu_onln = 0;
-#endif
 	BIF_RET(make_small(dirty_cpu_onln));
     } else if (ERTS_IS_ATOM_STR("dirty_io_schedulers", BIF_ARG_1)) {
 	Uint dirty_io;
-#ifdef ERTS_DIRTY_SCHEDULERS
 	erts_schedulers_state(NULL, NULL, NULL, NULL, NULL, NULL, &dirty_io, NULL);
-#else
-        dirty_io = 0;
-#endif
 	BIF_RET(make_small(dirty_io));
     } else if (ERTS_IS_ATOM_STR("run_queues", BIF_ARG_1)) {
 	res = make_small(erts_no_run_queues);
@@ -2780,7 +2690,7 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	BIF_RET(make_small(CONTEXT_REDS));
     } else if (ERTS_IS_ATOM_STR("kernel_poll", BIF_ARG_1)) {
 #ifdef ERTS_ENABLE_KERNEL_POLL
-	BIF_RET(erts_use_kernel_poll ? am_true : am_false);
+	BIF_RET(am_true);
 #else
 	BIF_RET(am_false);
 #endif    
@@ -2805,23 +2715,15 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
     } else if (ERTS_IS_ATOM_STR("check_io", BIF_ARG_1)) {
 	BIF_RET(erts_check_io_info(BIF_P));
     } else if (ERTS_IS_ATOM_STR("multi_scheduling_blockers", BIF_ARG_1)) {
-#ifndef ERTS_SMP
-	BIF_RET(NIL);
-#else
 	if (erts_no_schedulers == 1)
 	    BIF_RET(NIL);
 	else
 	    BIF_RET(erts_multi_scheduling_blockers(BIF_P, 0));
-#endif
     } else if (ERTS_IS_ATOM_STR("normal_multi_scheduling_blockers", BIF_ARG_1)) {
-#ifndef ERTS_SMP
-	BIF_RET(NIL);
-#else
 	if (erts_no_schedulers == 1)
 	    BIF_RET(NIL);
 	else
 	    BIF_RET(erts_multi_scheduling_blockers(BIF_P, 1));
-#endif
     } else if (ERTS_IS_ATOM_STR("modified_timing_level", BIF_ARG_1)) {
 	BIF_RET(ERTS_USE_MODIFIED_TIMING()
 		? make_small(erts_modified_timing_level)
@@ -2884,12 +2786,10 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	BIF_RET(am_false);
 #endif	
     }
-#ifdef ERTS_SMP
     else if (ERTS_IS_ATOM_STR("thread_progress", BIF_ARG_1)) {
 	erts_thr_progress_dbg_print_state();
 	BIF_RET(am_true);
     }
-#endif
     else if (BIF_ARG_1 == am_message_queue_data) {
 	switch (erts_default_spo_flags & (SPO_ON_HEAP_MSGQ|SPO_OFF_HEAP_MSGQ)) {
 	case SPO_OFF_HEAP_MSGQ:
@@ -2943,7 +2843,7 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	BIF_RET(am_disabled);
     }
     else if (ERTS_IS_ATOM_STR("eager_check_io",BIF_ARG_1)) {
-	BIF_RET(erts_eager_check_io ? am_true : am_false);
+	BIF_RET(am_true);
     }
     else if (ERTS_IS_ATOM_STR("literal_test",BIF_ARG_1)) {
 #ifdef ERTS_HAVE_IS_IN_LITERAL_RANGE
@@ -2981,7 +2881,7 @@ erts_bld_port_info(Eterm **hpp, ErlOffHeap *ohp, Uint *szp, Port *prt,
 {
     Eterm res = THE_NON_VALUE;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
     if (item == am_id) {
 	if (hpp)
@@ -3172,9 +3072,6 @@ erts_bld_port_info(Eterm **hpp, ErlOffHeap *ohp, Uint *szp, Port *prt,
     }
     else if (ERTS_IS_ATOM_STR("locking", item)) {
 	if (hpp) {
-#ifndef ERTS_SMP
-	    res = am_false;
-#else
 	    if (erts_atomic32_read_nob(&prt->state)
 		& ERTS_PORT_SFLG_PORT_SPECIFIC_LOCK) {
 		DECL_AM(port_level);
@@ -3188,7 +3085,6 @@ erts_bld_port_info(Eterm **hpp, ErlOffHeap *ohp, Uint *szp, Port *prt,
 			 & ERL_DRV_FLAG_USE_PORT_LOCKING));
 		res = AM_driver_level;
 	    }
-#endif
 	}
 	if (szp) {
 	    res = am_true;
@@ -3201,7 +3097,7 @@ erts_bld_port_info(Eterm **hpp, ErlOffHeap *ohp, Uint *szp, Port *prt,
 	    goto done;
 	}
 	res = ((ERTS_PTS_FLG_PARALLELISM &
-		erts_smp_atomic32_read_nob(&prt->sched.flags))
+		erts_atomic32_read_nob(&prt->sched.flags))
 	       ? am_true
 	       : am_false);
     }
@@ -3277,7 +3173,7 @@ fun_info_2(BIF_ALIST_2)
 	    }
 	    break;
 	case am_refc:
-	    val = erts_make_integer(erts_smp_atomic_read_nob(&funp->fe->refc), p);
+	    val = erts_make_integer(erts_atomic_read_nob(&funp->fe->refc), p);
 	    hp = HAlloc(p, 3);
 	    break;
 	case am_arity:
@@ -3382,7 +3278,7 @@ BIF_RETTYPE is_process_alive_1(BIF_ALIST_1)
 	   BIF_RET(am_false);
        }
        else {
-	   if (erts_smp_atomic32_read_acqb(&rp->state)
+	   if (erts_atomic32_read_acqb(&rp->state)
 		 & (ERTS_PSFLG_PENDING_EXIT|ERTS_PSFLG_EXITING))
 	       ERTS_BIF_AWAIT_X_DATA_TRAP(BIF_P, BIF_ARG_1, am_false);
 	   else
@@ -3417,7 +3313,7 @@ BIF_RETTYPE process_display_2(BIF_ALIST_2)
 		       BIF_ARG_1, BIF_ARG_2);
    if (rp != BIF_P && ERTS_PROC_PENDING_EXIT(rp)) {
        Eterm args[2] = {BIF_ARG_1, BIF_ARG_2};
-       erts_smp_proc_unlock(rp, ERTS_PROC_LOCKS_ALL);
+       erts_proc_unlock(rp, ERTS_PROC_LOCKS_ALL);
        ERTS_BIF_AWAIT_X_APPLY_TRAP(BIF_P,
 				   BIF_ARG_1,
 				   am_erlang,
@@ -3426,11 +3322,9 @@ BIF_RETTYPE process_display_2(BIF_ALIST_2)
 				   2);
    }
    erts_stack_dump(ERTS_PRINT_STDERR, NULL, rp);
-#ifdef ERTS_SMP
-   erts_smp_proc_unlock(rp, (BIF_P == rp
+   erts_proc_unlock(rp, (BIF_P == rp
 			     ? ERTS_PROC_LOCKS_ALL_MINOR
 			     : ERTS_PROC_LOCKS_ALL));
-#endif
    BIF_RET(am_true);
 }
 
@@ -3608,7 +3502,7 @@ BIF_RETTYPE error_logger_warning_map_0(BIF_ALIST_0)
     BIF_RET(erts_error_logger_warnings);
 }
 
-static erts_smp_atomic_t available_internal_state;
+static erts_atomic_t available_internal_state;
 
 static int empty_magic_ref_destructor(Binary *bin)
 {
@@ -3621,7 +3515,7 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
      * NOTE: Only supposed to be used for testing, and debugging.
      */
 
-    if (!erts_smp_atomic_read_nob(&available_internal_state)) {
+    if (!erts_atomic_read_nob(&available_internal_state)) {
 	BIF_ERROR(BIF_P, EXC_UNDEF);
     }
 
@@ -3664,9 +3558,9 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
 	    int no_errors;
 	    ErtsCheckIoDebugInfo ciodi = {0};
 #ifdef HAVE_ERTS_CHECK_IO_DEBUG
-	    erts_smp_proc_unlock(BIF_P,ERTS_PROC_LOCK_MAIN);
+	    erts_proc_unlock(BIF_P,ERTS_PROC_LOCK_MAIN);
 	    no_errors = erts_check_io_debug(&ciodi);
-	    erts_smp_proc_lock(BIF_P,ERTS_PROC_LOCK_MAIN);
+	    erts_proc_lock(BIF_P,ERTS_PROC_LOCK_MAIN);
 #else
 	    no_errors = 0;
 #endif
@@ -3681,8 +3575,8 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
 						   (Uint) ciodi.no_used_fds),
 				     erts_bld_uint(hpp, szp,
 						   (Uint) ciodi.no_driver_select_structs),
-				     erts_bld_uint(hpp, szp,
-						   (Uint) ciodi.no_driver_event_structs));
+                                     erts_bld_uint(hpp, szp,
+                                                   (Uint) ciodi.no_enif_select_structs));
 		if (hpp)
 		    break;
 		hp = HAlloc(BIF_P, sz);
@@ -3716,9 +3610,9 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
 	}
 	else if (ERTS_IS_ATOM_STR("nbalance", BIF_ARG_1)) {
 	    Uint n;
-	    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
 	    n = erts_debug_nbalance();
-	    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 	    BIF_RET(erts_make_integer(n, BIF_P));
 	}
 	else if (ERTS_IS_ATOM_STR("available_internal_state", BIF_ARG_1)) {
@@ -3733,11 +3627,11 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
 	}
 	else if (ERTS_IS_ATOM_STR("memory", BIF_ARG_1)) {
 	    Eterm res;
-	    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-	    erts_smp_thr_progress_block();
-	    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	    erts_thr_progress_block();
+	    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 	    res = erts_memory(NULL, NULL, BIF_P, THE_NON_VALUE);
-	    erts_smp_thr_progress_unblock();
+	    erts_thr_progress_unblock();
 	    BIF_RET(res);
 	}
         else if (ERTS_IS_ATOM_STR("mmap", BIF_ARG_1)) {
@@ -3780,6 +3674,12 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
 		Eterm *hp = HAlloc(BIF_P, hsz);
 		BIF_RET(uword_to_big(size, hp));
 	    }
+        } else if (ERTS_IS_ATOM_STR("scheduler_dump", BIF_ARG_1)) {
+#if defined(ERTS_HAVE_TRY_CATCH) && defined(ERTS_SYS_SUSPEND_SIGNAL)
+            BIF_RET(am_true);
+#else
+            BIF_RET(am_false);
+#endif
         }
     }
     else if (is_tuple(BIF_ARG_1)) {
@@ -3804,11 +3704,11 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
 				      tp[2],
 				      ERTS_PROC_LOCK_LINK);
 		    if (!p) {
-			ERTS_SMP_ASSERT_IS_NOT_EXITING(BIF_P);
+			ERTS_ASSERT_IS_NOT_EXITING(BIF_P);
 			BIF_RET(am_undefined);
 		    }
 		    res = make_link_list(BIF_P, ERTS_P_LINKS(p), NIL);
-		    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_LINK);
+		    erts_proc_unlock(p, ERTS_PROC_LOCK_LINK);
 		    BIF_RET(res);
 		}
 		else if(is_internal_port(tp[2])) {
@@ -3827,11 +3727,10 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
 		    DistEntry *dep = erts_find_dist_entry(tp[2]);
 		    if(dep) {
 			Eterm subres;
-			erts_smp_de_links_lock(dep);
+			erts_de_links_lock(dep);
 			subres = make_link_list(BIF_P, dep->nlinks, NIL);
 			subres = make_link_list(BIF_P, dep->node_links, subres);
-			erts_smp_de_links_unlock(dep);
-			erts_deref_dist_entry(dep);
+			erts_de_links_unlock(dep);
 			BIF_RET(subres);
 		    } else {
 			BIF_RET(am_undefined);
@@ -3849,20 +3748,19 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
 				      tp[2],
 				      ERTS_PROC_LOCK_LINK);
 		    if (!p) {
-			ERTS_SMP_ASSERT_IS_NOT_EXITING(BIF_P);
+			ERTS_ASSERT_IS_NOT_EXITING(BIF_P);
 			BIF_RET(am_undefined);
 		    }
 		    res = make_monitor_list(BIF_P, ERTS_P_MONITORS(p));
-		    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_LINK);
+		    erts_proc_unlock(p, ERTS_PROC_LOCK_LINK);
 		    BIF_RET(res);
 		} else if(is_node_name_atom(tp[2])) {
 		    DistEntry *dep = erts_find_dist_entry(tp[2]);
 		    if(dep) {
 			Eterm ml;
-			erts_smp_de_links_lock(dep);
+			erts_de_links_lock(dep);
 			ml = make_monitor_list(BIF_P, dep->monitors);
-			erts_smp_de_links_unlock(dep);
-			erts_deref_dist_entry(dep);
+			erts_de_links_unlock(dep);
 			BIF_RET(ml);
 		    } else {
 			BIF_RET(am_undefined);
@@ -3877,7 +3775,6 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
 		else {
 		    Uint cno = dist_entry_channel_no(dep);
 		    res = make_small(cno);
-		    erts_deref_dist_entry(dep);
 		}
 		BIF_RET(res);
 	    }
@@ -3889,7 +3786,7 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
 		}
 		else {
 		    Eterm res = ERTS_PROC_PENDING_EXIT(rp) ? am_true : am_false;
-		    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
+		    erts_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
 		    BIF_RET(res);
 		}
 	    }
@@ -3933,21 +3830,20 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
 		    BIF_RET(res);
 		}
 	    }
-	    else if (ERTS_IS_ATOM_STR("term_to_binary_no_funs", tp[1])) {
-		Uint dflags = (DFLAG_EXTENDED_REFERENCES |
-			       DFLAG_EXTENDED_PIDS_PORTS |
-			       DFLAG_BIT_BINARIES);
+	    else if (ERTS_IS_ATOM_STR("term_to_binary_tuple_fallbacks", tp[1])) {
+		Uint dflags = (TERM_TO_BINARY_DFLAGS
+                               & ~DFLAG_EXPORT_PTR_TAG
+                               & ~DFLAG_BIT_BINARIES);
 		BIF_RET(erts_term_to_binary(BIF_P, tp[2], 0, dflags));
 	    }
-	    else if (ERTS_IS_ATOM_STR("dist_port", tp[1])) {
+	    else if (ERTS_IS_ATOM_STR("dist_ctrl", tp[1])) {
 		Eterm res = am_undefined;
 		DistEntry *dep = erts_sysname_to_connected_dist_entry(tp[2]);
 		if (dep) {
-		    erts_smp_de_rlock(dep);
-		    if (is_internal_port(dep->cid))
+		    erts_de_rlock(dep);
+		    if (is_internal_port(dep->cid) || is_internal_pid(dep->cid))
 			res = dep->cid;
-		    erts_smp_de_runlock(dep);
-		    erts_deref_dist_entry(dep);
+		    erts_de_runlock(dep);
 		}
 		BIF_RET(res);
 	    }
@@ -4091,7 +3987,7 @@ BIF_RETTYPE erts_internal_system_check_1(BIF_ALIST_1)
     BIF_ERROR(BIF_P, BADARG);
 }
 
-static erts_smp_atomic_t hipe_test_reschedule_flag;
+static erts_atomic_t hipe_test_reschedule_flag;
 
 #if defined(VALGRIND) && defined(__GNUC__)
 /* Force noinline for valgrind suppression */
@@ -4115,7 +4011,7 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
     if (ERTS_IS_ATOM_STR("available_internal_state", BIF_ARG_1)
 	&& (BIF_ARG_2 == am_true || BIF_ARG_2 == am_false)) {
 	erts_aint_t on = (erts_aint_t) (BIF_ARG_2 == am_true);
-	erts_aint_t prev_on = erts_smp_atomic_xchg_nob(&available_internal_state, on);
+	erts_aint_t prev_on = erts_atomic_xchg_nob(&available_internal_state, on);
 	if (on) {
 	    erts_dsprintf_buf_t *dsbufp = erts_create_logger_dsbuf();
 	    erts_dsprintf(dsbufp, "Process %T ", BIF_P->common.id);
@@ -4131,7 +4027,7 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
 	BIF_RET(prev_on ? am_true : am_false);
     }
 
-    if (!erts_smp_atomic_read_nob(&available_internal_state)) {
+    if (!erts_atomic_read_nob(&available_internal_state)) {
 	BIF_ERROR(BIF_P, EXC_UNDEF);
     }
 
@@ -4155,13 +4051,13 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
 	    Sint ms;
 	    if (term_to_Sint(BIF_ARG_2, &ms) != 0) {
 		if (ms > 0) {
-		    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+		    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
 		    if (block)
-			erts_smp_thr_progress_block();
+			erts_thr_progress_block();
 		    while (erts_milli_sleep((long) ms) != 0);
 		    if (block)
-			erts_smp_thr_progress_unblock();
-		    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+			erts_thr_progress_unblock();
+		    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 		}
 		BIF_RET(am_true);
 	    }
@@ -4170,9 +4066,9 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
 	    Sint ms;
 	    if (term_to_Sint(BIF_ARG_2, &ms) != 0) {
 		if (ms > 0) {
-		    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+		    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
 		    while (erts_milli_sleep((long) ms) != 0);
-		    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+		    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 		}
 		BIF_RET(am_true);
 	    }
@@ -4240,10 +4136,8 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
 			BIF_RET(AM_dead);
 		    }
 
-#ifdef ERTS_SMP
 		    if (BIF_P == rp)
 			rp_locks |= ERTS_PROC_LOCK_MAIN;
-#endif
 		    xres = erts_send_exit_signal(NULL, /* NULL in order to
 							  force a pending exit
 							  when we send to our
@@ -4255,11 +4149,9 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
 						 NIL,
 						 NULL,
 						 0);
-#ifdef ERTS_SMP
 		    if (BIF_P == rp)
 			rp_locks &= ~ERTS_PROC_LOCK_MAIN;
-#endif
-		    erts_smp_proc_unlock(rp, rp_locks);
+		    erts_proc_unlock(rp, rp_locks);
 		    if (xres > 1) {
 			DECL_AM(message);
 			BIF_RET(AM_message);
@@ -4321,14 +4213,14 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
 	}
 	else if (ERTS_IS_ATOM_STR("hipe_test_reschedule_suspend", BIF_ARG_1)) {
 	    /* Used by hipe test suites */
-	    erts_aint_t flag = erts_smp_atomic_read_nob(&hipe_test_reschedule_flag);
+	    erts_aint_t flag = erts_atomic_read_nob(&hipe_test_reschedule_flag);
 	    if (!flag && BIF_ARG_2 != am_false) {
-		erts_smp_atomic_set_nob(&hipe_test_reschedule_flag, 1);
+		erts_atomic_set_nob(&hipe_test_reschedule_flag, 1);
 		erts_suspend(BIF_P, ERTS_PROC_LOCK_MAIN, NULL);
 		ERTS_BIF_YIELD2(bif_export[BIF_erts_debug_set_internal_state_2],
 				BIF_P, BIF_ARG_1, BIF_ARG_2);
 	    }
-	    erts_smp_atomic_set_nob(&hipe_test_reschedule_flag, !flag);
+	    erts_atomic_set_nob(&hipe_test_reschedule_flag, !flag);
 	    BIF_RET(NIL);
 	}
 	else if (ERTS_IS_ATOM_STR("hipe_test_reschedule_resume", BIF_ARG_1)) {
@@ -4339,7 +4231,7 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
 	    if (rp) {
 		erts_resume(rp, ERTS_PROC_LOCK_STATUS);
 		res = am_true;
-		erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
+		erts_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
 	    }
 	    BIF_RET(res);
 	}
@@ -4356,16 +4248,14 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
 		BIF_RET(am_false);
 	    else {
 		Uint32 con_id;
-		erts_smp_de_rlock(dep);
+		erts_de_rlock(dep);
 		con_id = dep->connection_id;
-		erts_smp_de_runlock(dep);
+		erts_de_runlock(dep);
 		erts_kill_dist_connection(dep, con_id);
-		erts_deref_dist_entry(dep);
 		BIF_RET(am_true);
 	    }
 	}
 	else if (ERTS_IS_ATOM_STR("not_running_optimization", BIF_ARG_1)) {
-#ifdef ERTS_SMP
 	    int old_use_opt, use_opt;
 	    switch (BIF_ARG_2) {
 	    case am_true:
@@ -4378,16 +4268,13 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
 		BIF_ERROR(BIF_P, BADARG);
 	    }
 
-	    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-	    erts_smp_thr_progress_block();
+	    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	    erts_thr_progress_block();
 	    old_use_opt = !erts_disable_proc_not_running_opt;
 	    erts_disable_proc_not_running_opt = !use_opt;
-	    erts_smp_thr_progress_unblock();
-	    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+	    erts_thr_progress_unblock();
+	    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 	    BIF_RET(old_use_opt ? am_true : am_false);
-#else
-	    BIF_ERROR(BIF_P,  EXC_NOTSUP);
-#endif
 	}
 	else if (ERTS_IS_ATOM_STR("wait", BIF_ARG_1)) {
 	    if (ERTS_IS_ATOM_STR("deallocations", BIF_ARG_2)) {
@@ -4415,9 +4302,9 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
 	    Sint64 msecs;
 	    if (term_to_Sint64(BIF_ARG_2, &msecs)) {
 		/* Negative value restore original value... */
-		erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+		erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
 		erts_debug_test_node_tab_delayed_delete(msecs);
-		erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+		erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 		BIF_RET(am_ok);
 	    }
 	}
@@ -4865,13 +4752,13 @@ static void os_info_init(void)
 void
 erts_bif_info_init(void)
 {
-    erts_smp_atomic_init_nob(&available_internal_state, 0);
-    erts_smp_atomic_init_nob(&hipe_test_reschedule_flag, 0);
+    erts_atomic_init_nob(&available_internal_state, 0);
+    erts_atomic_init_nob(&hipe_test_reschedule_flag, 0);
 
     alloc_info_trap = erts_export_put(am_erlang, am_alloc_info, 1);
     alloc_sizes_trap = erts_export_put(am_erlang, am_alloc_sizes, 1);
     gather_sched_wall_time_res_trap
-	= erts_export_put(am_erlang, am_gather_sched_wall_time_result, 1);
+	= erts_export_put(am_erts_internal, am_gather_sched_wall_time_result, 1);
     gather_gc_info_res_trap
 	= erts_export_put(am_erlang, am_gather_gc_info_result, 1);
     gather_io_bytes_trap
diff --git a/erts/emulator/beam/erl_bif_os.c b/erts/emulator/beam/erl_bif_os.c
index 5cd172c26f..910325a2f4 100644
--- a/erts/emulator/beam/erl_bif_os.c
+++ b/erts/emulator/beam/erl_bif_os.c
@@ -37,6 +37,8 @@
 #include "dist.h"
 #include "erl_version.h"
 
+static int check_env_name(char *name);
+
 /*
  * Return the pid for the Erlang process in the host OS.
  */
@@ -101,8 +103,10 @@ BIF_RETTYPE os_getenv_1(BIF_ALIST_1)
     key_str = erts_convert_filename_to_native(BIF_ARG_1,buf,STATIC_BUF_SIZE,
 					      ERTS_ALC_T_TMP,1,0,&len);
 
-    if (!key_str) {
-	BIF_ERROR(p, BADARG);
+    if (!check_env_name(key_str)) {
+        if (key_str && key_str != &buf[0])
+            erts_free(ERTS_ALC_T_TMP, key_str);
+        BIF_ERROR(p, BADARG);
     }
 
     if (key_str != &buf[0])
@@ -143,25 +147,20 @@ BIF_RETTYPE os_putenv_2(BIF_ALIST_2)
 {
     char def_buf_key[STATIC_BUF_SIZE];
     char def_buf_value[STATIC_BUF_SIZE];
-    char *key_buf, *value_buf;
+    char *key_buf = NULL, *value_buf = NULL;
 
     key_buf = erts_convert_filename_to_native(BIF_ARG_1,def_buf_key,
 					      STATIC_BUF_SIZE,
 					      ERTS_ALC_T_TMP,0,0,NULL);
-    if (!key_buf) {
-	BIF_ERROR(BIF_P, BADARG);
-    }
+    if (!check_env_name(key_buf))
+        goto badarg;
+
     value_buf = erts_convert_filename_to_native(BIF_ARG_2,def_buf_value,
 						STATIC_BUF_SIZE,
 						ERTS_ALC_T_TMP,1,0,
 						NULL);
-    if (!value_buf) {
-	if (key_buf != def_buf_key) {
-	    erts_free(ERTS_ALC_T_TMP, key_buf);
-	}
-	BIF_ERROR(BIF_P, BADARG);
-    }
-	    
+    if (!value_buf)
+        goto badarg;
 
     if (erts_sys_putenv(key_buf, value_buf)) {
 	if (key_buf != def_buf_key) {
@@ -179,6 +178,13 @@ BIF_RETTYPE os_putenv_2(BIF_ALIST_2)
 	erts_free(ERTS_ALC_T_TMP, value_buf);
     }
     BIF_RET(am_true);
+
+badarg:
+    if (key_buf && key_buf != def_buf_key)
+	erts_free(ERTS_ALC_T_TMP, key_buf);
+    if (value_buf && value_buf != def_buf_value)
+	erts_free(ERTS_ALC_T_TMP, value_buf);
+    BIF_ERROR(BIF_P, BADARG);
 }
 
 BIF_RETTYPE os_unsetenv_1(BIF_ALIST_1)
@@ -188,20 +194,21 @@ BIF_RETTYPE os_unsetenv_1(BIF_ALIST_1)
 
     key_buf = erts_convert_filename_to_native(BIF_ARG_1,buf,STATIC_BUF_SIZE,
 					      ERTS_ALC_T_TMP,0,0,NULL);
-    if (!key_buf) {
-	BIF_ERROR(BIF_P, BADARG);
-    }
+    if (!check_env_name(key_buf))
+        goto badarg;
+
+    if (erts_sys_unsetenv(key_buf))
+        goto badarg;
 
-    if (erts_sys_unsetenv(key_buf)) {
-	if (key_buf != buf) {
-	    erts_free(ERTS_ALC_T_TMP, key_buf);
-	}
-	BIF_ERROR(BIF_P, BADARG);
-    }
     if (key_buf != buf) {
 	erts_free(ERTS_ALC_T_TMP, key_buf);
     }
     BIF_RET(am_true);
+
+badarg:
+    if (key_buf && key_buf != buf)
+        erts_free(ERTS_ALC_T_TMP, key_buf);
+    BIF_ERROR(BIF_P, BADARG);    
 }
 
 BIF_RETTYPE os_set_signal_2(BIF_ALIST_2) {
@@ -217,3 +224,27 @@ BIF_RETTYPE os_set_signal_2(BIF_ALIST_2) {
 error:
     BIF_ERROR(BIF_P, BADARG);
 }
+
+static int
+check_env_name(char *raw_name)
+{
+    byte *c = (byte *) raw_name;
+    int encoding;
+
+    if (!c)
+        return 0;
+    
+    encoding = erts_get_native_filename_encoding();
+
+    if (erts_raw_env_char_is_7bit_ascii_char('\0', c, encoding))
+        return 0; /* Do not allow empty name... */
+
+    /* Verify no '=' characters in variable name... */
+    do {
+        if (erts_raw_env_char_is_7bit_ascii_char('=', c, encoding))
+            return 0;
+        c = erts_raw_env_next_char(c, encoding);
+    } while (!erts_raw_env_char_is_7bit_ascii_char('\0', c, encoding));
+
+    return 1; /* Seems ok... */
+}
diff --git a/erts/emulator/beam/erl_bif_port.c b/erts/emulator/beam/erl_bif_port.c
index ff03151619..c4a4dd5863 100644
--- a/erts/emulator/beam/erl_bif_port.c
+++ b/erts/emulator/beam/erl_bif_port.c
@@ -45,7 +45,7 @@
 #include "dtrace-wrapper.h"
 
 static Port *open_port(Process* p, Eterm name, Eterm settings, int *err_typep, int *err_nump);
-static byte* convert_environment(Process* p, Eterm env);
+static char* convert_environment(Eterm env);
 static char **convert_args(Eterm);
 static void free_args(char **);
 
@@ -86,25 +86,25 @@ BIF_RETTYPE erts_internal_open_port_2(BIF_ALIST_2)
         erts_make_ref_in_array(port->async_open_port->ref);
         port->async_open_port->to = BIF_P->common.id;
 
-        erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCKS_MSG_RECEIVE | ERTS_PROC_LOCK_LINK);
+        erts_proc_lock(BIF_P, ERTS_PROC_LOCKS_MSG_RECEIVE | ERTS_PROC_LOCK_LINK);
         if (ERTS_PROC_PENDING_EXIT(BIF_P)) {
 	    /* need to exit caller instead */
-	    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCKS_MSG_RECEIVE | ERTS_PROC_LOCK_LINK);
+	    erts_proc_unlock(BIF_P, ERTS_PROC_LOCKS_MSG_RECEIVE | ERTS_PROC_LOCK_LINK);
 	    KILL_CATCHES(BIF_P);
 	    BIF_P->freason = EXC_EXIT;
             erts_port_release(port);
             BIF_RET(am_badarg);
 	}
 
-	ERTS_SMP_MSGQ_MV_INQ2PRIVQ(BIF_P);
+	ERTS_MSGQ_MV_INQ2PRIVQ(BIF_P);
 	BIF_P->msg.save = BIF_P->msg.last;
 
-	erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	erts_proc_unlock(BIF_P, ERTS_PROC_LOCKS_MSG_RECEIVE);
 
         res = erts_proc_store_ref(BIF_P, port->async_open_port->ref);
     } else {
         res = port->common.id;
-        erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK);
+        erts_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK);
     }
 
     erts_add_link(&ERTS_P_LINKS(port), LINK_PID, BIF_P->common.id);
@@ -114,7 +114,7 @@ BIF_RETTYPE erts_internal_open_port_2(BIF_ALIST_2)
         trace_proc(BIF_P, ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_LINK, BIF_P,
                    am_link, port->common.id);
 
-    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
+    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
 
     erts_port_release(port);
 
@@ -271,12 +271,10 @@ BIF_RETTYPE erts_internal_port_call_3(BIF_ALIST_3)
 	break;
     }
 
-    state = erts_smp_atomic32_read_acqb(&BIF_P->state);
+    state = erts_atomic32_read_acqb(&BIF_P->state);
     if (state & (ERTS_PSFLG_EXITING|ERTS_PSFLG_PENDING_EXIT)) {
-#ifdef ERTS_SMP
 	if (state & ERTS_PSFLG_PENDING_EXIT)
 	    erts_handle_pending_exit(BIF_P, ERTS_PROC_LOCK_MAIN);
-#endif
 	ERTS_BIF_EXITED(BIF_P);
     }
 
@@ -321,12 +319,10 @@ BIF_RETTYPE erts_internal_port_control_3(BIF_ALIST_3)
 	break;
     }
 
-    state = erts_smp_atomic32_read_acqb(&BIF_P->state);
+    state = erts_atomic32_read_acqb(&BIF_P->state);
     if (state & (ERTS_PSFLG_EXITING|ERTS_PSFLG_PENDING_EXIT)) {
-#ifdef ERTS_SMP
 	if (state & ERTS_PSFLG_PENDING_EXIT)
 	    erts_handle_pending_exit(BIF_P, ERTS_PROC_LOCK_MAIN);
-#endif
 	ERTS_BIF_EXITED(BIF_P);
     }
 
@@ -511,39 +507,35 @@ cleanup_old_port_data(erts_aint_t data)
 	ASSERT(is_immed((Eterm) data));
     }
     else {
-#ifdef ERTS_SMP
 	ErtsPortDataHeap *pdhp = (ErtsPortDataHeap *) data;
 	size_t size;
-	ERTS_SMP_DATA_DEPENDENCY_READ_MEMORY_BARRIER;
+	ERTS_THR_DATA_DEPENDENCY_READ_MEMORY_BARRIER;
 	size = sizeof(ErtsPortDataHeap) + (pdhp->hsize-1)*sizeof(Eterm);
 	erts_schedule_thr_prgr_later_cleanup_op(free_port_data_heap,
 						(void *) pdhp,
 						&pdhp->later_op,
 						size);
-#else
-	free_port_data_heap((void *) data);
-#endif
     }
 }
 
 void
 erts_init_port_data(Port *prt)
 {
-    erts_smp_atomic_init_nob(&prt->data, (erts_aint_t) am_undefined);
+    erts_atomic_init_nob(&prt->data, (erts_aint_t) am_undefined);
 }
 
 void
 erts_cleanup_port_data(Port *prt)
 {
     ASSERT(erts_atomic32_read_nob(&prt->state) & ERTS_PORT_SFLGS_INVALID_LOOKUP);
-    cleanup_old_port_data(erts_smp_atomic_xchg_nob(&prt->data,
+    cleanup_old_port_data(erts_atomic_xchg_nob(&prt->data,
 						   (erts_aint_t) NULL));
 }
 
 Uint
 erts_port_data_size(Port *prt)
 {
-    erts_aint_t data = erts_smp_atomic_read_ddrb(&prt->data);
+    erts_aint_t data = erts_atomic_read_ddrb(&prt->data);
 
     if ((data & 0x3) != 0) {
 	ASSERT(is_immed((Eterm) (UWord) data));
@@ -558,7 +550,7 @@ erts_port_data_size(Port *prt)
 ErlOffHeap *
 erts_port_data_offheap(Port *prt)
 {
-    erts_aint_t data = erts_smp_atomic_read_ddrb(&prt->data);
+    erts_aint_t data = erts_atomic_read_ddrb(&prt->data);
 
     if ((data & 0x3) != 0) {
 	ASSERT(is_immed((Eterm) (UWord) data));
@@ -603,11 +595,11 @@ BIF_RETTYPE port_set_data_2(BIF_ALIST_2)
 	ASSERT((data & 0x3) == 0);
     }
 
-    data = erts_smp_atomic_xchg_wb(&prt->data, data);
+    data = erts_atomic_xchg_wb(&prt->data, data);
 
     if (data == (erts_aint_t)NULL) {
 	/* Port terminated by racing thread */
-	data = erts_smp_atomic_xchg_wb(&prt->data, data);
+	data = erts_atomic_xchg_wb(&prt->data, data);
 	ASSERT(data != (erts_aint_t)NULL);
 	cleanup_old_port_data(data);
 	BIF_ERROR(BIF_P, BADARG);
@@ -630,7 +622,7 @@ BIF_RETTYPE port_get_data_1(BIF_ALIST_1)
     if (!prt)
         BIF_ERROR(BIF_P, BADARG);
 
-    data = erts_smp_atomic_read_ddrb(&prt->data);
+    data = erts_atomic_read_ddrb(&prt->data);
     if (data == (erts_aint_t)NULL)
         BIF_ERROR(BIF_P, BADARG);  /* Port terminated by racing thread */
 
@@ -726,11 +718,11 @@ open_port(Process* p, Eterm name, Eterm settings, int *err_typep, int *err_nump)
 			goto badarg;
 		    }
 		} else if (option == am_env) {
-		    byte* bytes;
-		    if ((bytes = convert_environment(p, *tp)) == NULL) {
+                    if (opts.envir) /* ignore previous env option... */
+                        erts_free(ERTS_ALC_T_OPEN_PORT_ENV, opts.envir);
+                    opts.envir = convert_environment(*tp);
+                    if (!opts.envir)
 			goto badarg;
-		    }
-		    opts.envir = (char *) bytes;
 		} else if (option == am_args) {
 		    char **av;
 		    char **oav = opts.argv;
@@ -925,7 +917,7 @@ open_port(Process* p, Eterm name, Eterm settings, int *err_typep, int *err_nump)
     }
     
 
-    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
+    erts_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
 
     port = erts_open_driver(driver, p->common.id, name_buf, &opts, err_typep, err_nump);
 #ifdef USE_VM_PROBES
@@ -942,7 +934,7 @@ open_port(Process* p, Eterm name, Eterm settings, int *err_typep, int *err_nump)
     if (port && IS_TRACED_FL(port, F_TRACE_PORTS))
         trace_port(port, am_getting_linked, p->common.id);
 
-    erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
+    erts_proc_lock(p, ERTS_PROC_LOCK_MAIN);
 
     if (IS_TRACED_FL(p, F_TRACE_SCHED_PROCS)) {
         trace_sched(p, ERTS_PROC_LOCK_MAIN, am_in);
@@ -964,6 +956,8 @@ open_port(Process* p, Eterm name, Eterm settings, int *err_typep, int *err_nump)
 	erts_atomic32_read_bor_relb(&port->state, sflgs);
  
  do_return:
+    if (opts.envir)
+        erts_free(ERTS_ALC_T_OPEN_PORT_ENV, opts.envir);
     if (name_buf)
 	erts_free(ERTS_ALC_T_TMP, (void *) name_buf);
     if (opts.argv) {
@@ -1029,74 +1023,129 @@ static void free_args(char **av)
     }
     erts_free(ERTS_ALC_T_TMP, av);
 }
-    
 
-static byte* convert_environment(Process* p, Eterm env)
+#ifdef DEBUG
+#define ERTS_CONV_ENV_BUF_EXTRA 2
+#else
+#define ERTS_CONV_ENV_BUF_EXTRA 1024
+#endif
+
+static char* convert_environment(Eterm env)
 {
-    Eterm all;
-    Eterm* temp_heap;
-    Eterm* hp;
-    Uint heap_size;
-    Sint n;
-    Sint size;
+    /*
+     * Returns environment buffer in memory allocated
+     * as ERTS_ALC_T_OPEN_PORT_ENV. Caller *needs*
+     * to deallocate...
+     */
+
+    Sint size, alloc_size;
     byte* bytes;
     int encoding = erts_get_native_filename_encoding();
 
-    if ((n = erts_list_length(env)) < 0) {
-	return NULL;
-    }
-    heap_size = 2*(5*n+1);
-    temp_heap = hp = (Eterm *) erts_alloc(ERTS_ALC_T_TMP, heap_size*sizeof(Eterm));
-    bytes = NULL;		/* Indicating error */
+    alloc_size = ERTS_CONV_ENV_BUF_EXTRA;
+    bytes = erts_alloc(ERTS_ALC_T_OPEN_PORT_ENV,
+                       alloc_size);
+    size = 0;
 
-    /*
-     * All errors below are handled by jumping to 'done', to ensure that the memory
-     * gets deallocated. Do NOT return directly from this function.
-     */
+    /* ERTS_CONV_ENV_BUF_EXTRA >= for end delimiter... */
+    ERTS_CT_ASSERT(ERTS_CONV_ENV_BUF_EXTRA >= 2);
 
-    all = CONS(hp, make_small(0), NIL);
-    hp += 2;
+    while (is_list(env)) {
+        Sint var_sz, val_sz, need;
+        byte *str, *limit;
+	Eterm tmp, *tp, *consp;
 
-    while(is_list(env)) {
-	Eterm tmp;
-	Eterm* tp;
+        consp = list_val(env);
+	tmp = CAR(consp);
+	if (is_not_tuple_arity(tmp, 2))
+	    goto error;
 
-	tmp = CAR(list_val(env));
-	if (is_not_tuple_arity(tmp, 2)) {
-	    goto done;
-	}
 	tp = tuple_val(tmp);
-	tmp = CONS(hp, make_small(0), NIL);
-	hp += 2;
-	if (tp[2] != am_false) {
-	    tmp = CONS(hp, tp[2], tmp);
-	    hp += 2;
-	}
-	tmp = CONS(hp, make_small('='), tmp);
-	hp += 2;
-	tmp = CONS(hp, tp[1], tmp);
-	hp += 2;
-	all = CONS(hp, tmp, all);
-	hp += 2;
-	env = CDR(list_val(env));
-    }
-    if (is_not_nil(env)) {
-	goto done;
-    }
 
-    if ((size = erts_native_filename_need(all,encoding)) < 0) {
-	goto done;
+        /* Check encoding of env variable... */
+        if (is_not_list(tp[1]))
+            goto error;
+        var_sz = erts_native_filename_need(tp[1], encoding);
+        if (var_sz <= 0)
+            goto error;
+        /* Check encoding of value... */
+        if (tp[2] == am_false || is_nil(tp[2]))
+            val_sz = 0;
+        else if (is_not_list(tp[2]))
+            goto error;
+        else {
+            val_sz = erts_native_filename_need(tp[2], encoding);
+            if (val_sz < 0)
+                goto error;
+        }
+
+        /* Ensure enough memory... */
+        need = size;
+        need += var_sz + val_sz;
+        /* '=' and '\0' */
+        need += 2 * erts_raw_env_7bit_ascii_char_need(encoding);
+        if (need > alloc_size) {
+            alloc_size = (need - alloc_size) + alloc_size;
+            alloc_size += ERTS_CONV_ENV_BUF_EXTRA;
+            bytes = erts_realloc(ERTS_ALC_T_OPEN_PORT_ENV,
+                                 bytes, alloc_size);
+        }
+
+        /* Write environment variable name... */
+        str = bytes + size;
+        erts_native_filename_put(tp[1], encoding, str);
+        /* empty variable name is not allowed... */
+        if (erts_raw_env_char_is_7bit_ascii_char('\0', str, encoding))
+            goto error;
+
+        /*
+         * Drop null characters at the end and verify that we do
+         * not have any '=' characters in the name...
+         */
+        limit = str + var_sz;
+        while (str < limit) {
+            if (erts_raw_env_char_is_7bit_ascii_char('\0', str, encoding))
+                break;
+            if (erts_raw_env_char_is_7bit_ascii_char('=', str, encoding))
+                goto error;
+            str = erts_raw_env_next_char(str, encoding);
+        }
+
+        /* Write the equals sign... */
+        str = erts_raw_env_7bit_ascii_char_put('=', str, encoding);
+
+        /* Write the value... */
+        if (val_sz > 0) {
+            limit = str + val_sz;
+            erts_native_filename_put(tp[2], encoding, str);
+            while (str < limit) {
+                if (erts_raw_env_char_is_7bit_ascii_char('\0', str, encoding))
+                    break;
+                str = erts_raw_env_next_char(str, encoding);
+            }
+        }
+
+        /* Delimit... */
+        str = erts_raw_env_7bit_ascii_char_put('\0', str, encoding);
+
+        size = str - bytes;
+        ASSERT(size <= alloc_size);
+
+        env = CDR(consp);
     }
 
-    /*
-     * Put the result in a binary (no risk for a memory leak that way).
-     */
-    (void) erts_new_heap_binary(p, NULL, size, &bytes);
-    erts_native_filename_put(all,encoding,bytes);
+    /* End delimit... */
+    (void) erts_raw_env_7bit_ascii_char_put('\0', &bytes[size], encoding);
+
+    if (is_nil(env))
+        return (char *) bytes;
+
+error:
+
+    if (bytes)
+        erts_free(ERTS_ALC_T_OPEN_PORT_ENV, bytes);
 
- done:
-    erts_free(ERTS_ALC_T_TMP, temp_heap);
-    return bytes;
+    return (char *) NULL; /* error... */
 }
 
 /* ------------ decode_packet() and friends: */
diff --git a/erts/emulator/beam/erl_bif_re.c b/erts/emulator/beam/erl_bif_re.c
index ad124fd979..bc819505e7 100644
--- a/erts/emulator/beam/erl_bif_re.c
+++ b/erts/emulator/beam/erl_bif_re.c
@@ -66,11 +66,7 @@ static void erts_erts_pcre_stack_free(void *ptr) {
 
 #define ERTS_PCRE_STACK_MARGIN (10*1024)
 
-#ifdef ERTS_SMP
 #  define ERTS_STACK_LIMIT ((char *) ethr_get_stacklimit())
-#else
-#  define ERTS_STACK_LIMIT ((char *) erts_scheduler_stack_limit)
-#endif
 
 static int
 stack_guard_downwards(void)
diff --git a/erts/emulator/beam/erl_bif_trace.c b/erts/emulator/beam/erl_bif_trace.c
index 45159c4392..22942b40c4 100644
--- a/erts/emulator/beam/erl_bif_trace.c
+++ b/erts/emulator/beam/erl_bif_trace.c
@@ -60,10 +60,8 @@ static struct {			/* Protected by code write permission */
     int local;
     BpFunctions f;		/* Local functions */
     BpFunctions e;		/* Export entries */
-#ifdef ERTS_SMP
     Process* stager;
     ErtsThrPrgrLaterOp lop;
-#endif
 } finish_bp;
 
 static Eterm
@@ -71,9 +69,7 @@ trace_pattern(Process* p, Eterm MFA, Eterm Pattern, Eterm flaglist);
 static int
 erts_set_tracing_event_pattern(Eterm event, Binary*, int on);
 
-#ifdef ERTS_SMP
 static void smp_bp_finisher(void* arg);
-#endif
 static BIF_RETTYPE
 system_monitor(Process *p, Eterm monitor_pid, Eterm list);
 
@@ -345,7 +341,6 @@ trace_pattern(Process* p, Eterm MFA, Eterm Pattern, Eterm flaglist)
 
     ERTS_TRACER_CLEAR(&meta_tracer);
 
-#ifdef ERTS_SMP
     if (finish_bp.current >= 0) {
 	ASSERT(matches >= 0);
 	ASSERT(finish_bp.stager == NULL);
@@ -355,7 +350,6 @@ trace_pattern(Process* p, Eterm MFA, Eterm Pattern, Eterm flaglist)
 	erts_suspend(p, ERTS_PROC_LOCK_MAIN, NULL);
 	ERTS_BIF_YIELD_RETURN(p, make_small(matches));
     }
-#endif
 
     erts_release_code_write_permission();
 
@@ -367,7 +361,6 @@ trace_pattern(Process* p, Eterm MFA, Eterm Pattern, Eterm flaglist)
     }
 }
 
-#ifdef ERTS_SMP
 static void smp_bp_finisher(void* null)
 {
     if (erts_finish_breakpointing()) { /* Not done */
@@ -380,15 +373,14 @@ static void smp_bp_finisher(void* null)
 	finish_bp.stager = NULL;
 #endif
 	erts_release_code_write_permission();
-	erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
 	if (!ERTS_PROC_IS_EXITING(p)) {
 	    erts_resume(p, ERTS_PROC_LOCK_STATUS);
 	}
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
 	erts_proc_dec_refc(p);
     }
 }
-#endif /* ERTS_SMP */
 
 void
 erts_get_default_trace_pattern(int *trace_pattern_is_on,
@@ -397,8 +389,8 @@ erts_get_default_trace_pattern(int *trace_pattern_is_on,
 			       struct trace_pattern_flags *trace_pattern_flags,
 			       ErtsTracer *meta_tracer)
 {
-    ERTS_SMP_LC_ASSERT(erts_has_code_write_permission() ||
-		       erts_smp_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(erts_has_code_write_permission() ||
+		       erts_thr_progress_is_blocking());
     if (trace_pattern_is_on)
 	*trace_pattern_is_on = erts_default_trace_pattern_is_on;
     if (match_spec)
@@ -413,8 +405,8 @@ erts_get_default_trace_pattern(int *trace_pattern_is_on,
 
 int erts_is_default_trace_enabled(void)
 {
-    ERTS_SMP_LC_ASSERT(erts_has_code_write_permission() ||
-		       erts_smp_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(erts_has_code_write_permission() ||
+		       erts_thr_progress_is_blocking());
     return erts_default_trace_pattern_is_on;
 }
 
@@ -543,9 +535,7 @@ Eterm erts_internal_trace_3(BIF_ALIST_3)
     int matches = 0;
     Uint mask = 0;
     int cpu_ts = 0;
-#ifdef ERTS_SMP
     int system_blocked = 0;
-#endif
 
     if (! erts_trace_flags(list, &mask, &tracer, &cpu_ts)) {
 	BIF_ERROR(p, BADARG);
@@ -620,13 +610,13 @@ Eterm erts_internal_trace_3(BIF_ALIST_3)
 	    goto error;
 
         if (start_trace(tracee_p, tracer, &tracee_p->common, on, mask)) {
-	    erts_smp_proc_unlock(tracee_p,
+	    erts_proc_unlock(tracee_p,
 				 (tracee_p == p
 				  ? ERTS_PROC_LOCKS_ALL_MINOR
 				  : ERTS_PROC_LOCKS_ALL));
 	    goto already_traced;
         }
-        erts_smp_proc_unlock(tracee_p,
+        erts_proc_unlock(tracee_p,
 			     (tracee_p == p
 			      ? ERTS_PROC_LOCKS_ALL_MINOR
 			      : ERTS_PROC_LOCKS_ALL));
@@ -699,11 +689,9 @@ Eterm erts_internal_trace_3(BIF_ALIST_3)
                     mods = 1;
             }
 
-#ifdef ERTS_SMP
-	    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
-	    erts_smp_thr_progress_block();
+	    erts_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
+	    erts_thr_progress_block();
 	    system_blocked = 1;
-#endif
 
 	    ok = 1;
 	    if (procs || mods) {
@@ -766,12 +754,10 @@ Eterm erts_internal_trace_3(BIF_ALIST_3)
 	    goto error;
     }
 
-#ifdef ERTS_SMP
     if (system_blocked) {
-	erts_smp_thr_progress_unblock();
-	erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_unblock();
+	erts_proc_lock(p, ERTS_PROC_LOCK_MAIN);
     }
-#endif
     erts_release_code_write_permission();
     ERTS_TRACER_CLEAR(&tracer);
 
@@ -785,12 +771,10 @@ Eterm erts_internal_trace_3(BIF_ALIST_3)
 
     ERTS_TRACER_CLEAR(&tracer);
 
-#ifdef ERTS_SMP
     if (system_blocked) {
-	erts_smp_thr_progress_unblock();
-	erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_unblock();
+	erts_proc_lock(p, ERTS_PROC_LOCK_MAIN);
     }
-#endif
     erts_release_code_write_permission();
 
     BIF_ERROR(p, BADARG);
@@ -878,7 +862,7 @@ trace_info_pid(Process* p, Eterm pid_spec, Eterm key)
         trace_flags = ERTS_TRACE_FLAGS(tracee);
 
 	if (tracee != p)
-	    erts_smp_proc_unlock(tracee, ERTS_PROC_LOCK_MAIN);
+	    erts_proc_unlock(tracee, ERTS_PROC_LOCK_MAIN);
     } else if (is_external_pid(pid_spec)
 	       && external_pid_dist_entry(pid_spec) == erts_this_dist_entry) {
 	    return am_undefined;
@@ -982,12 +966,12 @@ static int function_is_traced(Process *p,
     if ((ep = export_get(&e)) != NULL) {
 	pc = ep->beam;
 	if (ep->addressv[erts_active_code_ix()] == pc &&
-	    *pc != (BeamInstr) em_call_error_handler) {
+	    ! BeamIsOpCode(*pc, op_call_error_handler)) {
 
 	    int r = 0;
 
-	    ASSERT(*pc == (BeamInstr) em_apply_bif ||
-		   *pc == (BeamInstr) BeamOp(op_i_generic_breakpoint));
+	    ASSERT(BeamIsOpCode(*pc, op_apply_bif) ||
+		   BeamIsOpCode(*pc, op_i_generic_breakpoint));
 
 	    if (erts_is_trace_break(&ep->info, ms, 0)) {
 		return FUNC_TRACE_GLOBAL_TRACE;
@@ -1055,28 +1039,20 @@ trace_info_func(Process* p, Eterm func_spec, Eterm key)
     mfa[1] = tp[2];
     mfa[2] = signed_val(tp[3]);
 
-#ifdef ERTS_SMP
     if ( (key == am_call_time) || (key == am_all)) {
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
-	erts_smp_thr_progress_block();
+	erts_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_block();
     }
-#endif
-#ifdef ERTS_DIRTY_SCHEDULERS
-    erts_smp_mtx_lock(&erts_dirty_bp_ix_mtx);
-#endif
+    erts_mtx_lock(&erts_dirty_bp_ix_mtx);
 
 
     r = function_is_traced(p, mfa, &ms, &ms_meta, &meta, &count, &call_time);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
-    erts_smp_mtx_unlock(&erts_dirty_bp_ix_mtx);
-#endif
-#ifdef ERTS_SMP
+    erts_mtx_unlock(&erts_dirty_bp_ix_mtx);
     if ( (key == am_call_time) || (key == am_all)) {
-	erts_smp_thr_progress_unblock();
-	erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_unblock();
+	erts_proc_lock(p, ERTS_PROC_LOCK_MAIN);
     }
-#endif
 
     switch (r) {
     case FUNC_TRACE_NOEXIST:
@@ -1385,14 +1361,14 @@ erts_set_trace_pattern(Process*p, ErtsCodeMFA *mfa, int specified,
 	    if (ep->addressv[code_ix] != pc) {
 		fp[i].mod->curr.num_traced_exports++;
 #ifdef DEBUG
-		ep->info.op = (BeamInstr) BeamOp(op_i_func_info_IaaI);
+		ep->info.op = BeamOpCodeAddr(op_i_func_info_IaaI);
 #endif
-                ep->beam[0] = (BeamInstr) BeamOp(op_jump_f);
+                ep->beam[0] = BeamOpCodeAddr(op_trace_jump_W);
 		ep->beam[1] = (BeamInstr) ep->addressv[code_ix];
 	    }
 	    erts_set_call_trace_bif(ci, match_prog_set, 0);
 	    if (ep->addressv[code_ix] != pc) {
-		ep->beam[0] = (BeamInstr) BeamOp(op_i_generic_breakpoint);
+		ep->beam[0] = BeamOpCodeAddr(op_i_generic_breakpoint);
 	    }
 	} else if (!on && flags.breakpoint) {
 	    /* Turn off breakpoint tracing -- nothing to do here. */
@@ -1402,8 +1378,8 @@ erts_set_trace_pattern(Process*p, ErtsCodeMFA *mfa, int specified,
 	     * before turning on breakpoint tracing.
 	     */
 	    erts_clear_call_trace_bif(ci, 0);
-	    if (ep->beam[0] == (BeamInstr) BeamOp(op_i_generic_breakpoint)) {
-		ep->beam[0] = (BeamInstr) BeamOp(op_jump_f);
+	    if (BeamIsOpCode(ep->beam[0], op_i_generic_breakpoint)) {
+		ep->beam[0] = BeamOpCodeAddr(op_trace_jump_W);
 	    }
 	}
     }
@@ -1526,17 +1502,13 @@ erts_set_trace_pattern(Process*p, ErtsCodeMFA *mfa, int specified,
     finish_bp.install = on;
     finish_bp.local = flags.breakpoint;
 
-#ifdef ERTS_SMP
     if (is_blocking) {
-	ERTS_SMP_LC_ASSERT(erts_smp_thr_progress_is_blocking());
-#endif
+	ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
 	while (erts_finish_breakpointing()) {
 	    /* Empty loop body */
 	}
-#ifdef ERTS_SMP
 	finish_bp.current = -1;
     }
-#endif
 
     if (flags.breakpoint) {
 	matches += finish_bp.f.matched;
@@ -1571,11 +1543,6 @@ erts_set_tracing_event_pattern(Eterm event, Binary* match_spec, int on)
     finish_bp.f.matched = 0;
     finish_bp.f.matching = NULL;
 
-#ifndef ERTS_SMP
-    while (erts_finish_breakpointing()) {
-        /* Empty loop body */
-    }
-#endif
     return 1;
 }
 
@@ -1594,7 +1561,7 @@ consolidate_event_tracing(ErtsTracingEvent te[])
 int
 erts_finish_breakpointing(void)
 {
-    ERTS_SMP_LC_ASSERT(erts_has_code_write_permission());
+    ERTS_LC_ASSERT(erts_has_code_write_permission());
 
     /*
      * Memory barriers will be issued for all schedulers *before*
@@ -1704,7 +1671,7 @@ uninstall_exp_breakpoints(BpFunctions* f)
 	if (ep->addressv[code_ix] != ep->beam) {
 	    continue;
 	}
-	ASSERT(ep->beam[0] == (BeamInstr) BeamOp(op_jump_f));
+	ASSERT(BeamIsOpCode(ep->beam[0], op_trace_jump_W));
 	ep->addressv[code_ix] = (BeamInstr *) ep->beam[1];
     }
 }
@@ -1723,7 +1690,7 @@ clean_export_entries(BpFunctions* f)
 	if (ep->addressv[code_ix] == ep->beam) {
 	    continue;
 	}
-	if (ep->beam[0] == (BeamInstr) BeamOp(op_jump_f)) {
+	if (BeamIsOpCode(ep->beam[0], op_trace_jump_W)) {
 	    ep->beam[0] = (BeamInstr) 0;
 	    ep->beam[1] = (BeamInstr) 0;
 	}
@@ -2015,24 +1982,20 @@ BIF_RETTYPE seq_trace_print_2(BIF_ALIST_2)
 }
 
 void erts_system_monitor_clear(Process *c_p) {
-#ifdef ERTS_SMP
     if (c_p) {
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
-	erts_smp_thr_progress_block();
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_block();
     }
-#endif
     erts_set_system_monitor(NIL);
     erts_system_monitor_long_gc = 0;
     erts_system_monitor_long_schedule = 0;
     erts_system_monitor_large_heap = 0;
     erts_system_monitor_flags.busy_port = 0;
     erts_system_monitor_flags.busy_dist_port = 0;
-#ifdef ERTS_SMP
     if (c_p) {
-	erts_smp_thr_progress_unblock();
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_unblock();
+	erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
     }
-#endif
 }
 
 
@@ -2142,8 +2105,8 @@ system_monitor(Process *p, Eterm monitor_pid, Eterm list)
 	int busy_port, busy_dist_port;
 
 	system_blocked = 1;
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
-	erts_smp_thr_progress_block();
+	erts_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_block();
 
 	if (!erts_pid2proc(p, ERTS_PROC_LOCK_MAIN, monitor_pid, 0))
 	    goto error;
@@ -2182,16 +2145,16 @@ system_monitor(Process *p, Eterm monitor_pid, Eterm list)
 	erts_system_monitor_flags.busy_port = !!busy_port;
 	erts_system_monitor_flags.busy_dist_port = !!busy_dist_port;
 
-	erts_smp_thr_progress_unblock();
-	erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_unblock();
+	erts_proc_lock(p, ERTS_PROC_LOCK_MAIN);
 	BIF_RET(prev);
     }
 
  error:
 
     if (system_blocked) {
-	erts_smp_thr_progress_unblock();
-	erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_unblock();
+	erts_proc_lock(p, ERTS_PROC_LOCK_MAIN);
     }
 
     BIF_ERROR(p, BADARG);
@@ -2200,23 +2163,19 @@ system_monitor(Process *p, Eterm monitor_pid, Eterm list)
 /* Begin: Trace for System Profiling */
 
 void erts_system_profile_clear(Process *c_p) {
-#ifdef ERTS_SMP
     if (c_p) {
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
-	erts_smp_thr_progress_block();
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_block();
     }
-#endif
     erts_set_system_profile(NIL);
     erts_system_profile_flags.scheduler = 0;
     erts_system_profile_flags.runnable_procs = 0;
     erts_system_profile_flags.runnable_ports = 0;
     erts_system_profile_flags.exclusive = 0;
-#ifdef ERTS_SMP
     if (c_p) {
-	erts_smp_thr_progress_unblock();
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_unblock();
+	erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
     }
-#endif
 }
 
 static Eterm system_profile_get(Process *p) {
@@ -2278,8 +2237,8 @@ BIF_RETTYPE system_profile_2(BIF_ALIST_2)
 	int scheduler, runnable_procs, runnable_ports, exclusive;
 	system_blocked = 1;
 	
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
-	erts_smp_thr_progress_block();
+	erts_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_block();
 
 	/* Check if valid process, no locks are taken */
 
@@ -2330,8 +2289,8 @@ BIF_RETTYPE system_profile_2(BIF_ALIST_2)
 	erts_system_profile_flags.runnable_procs = !!runnable_procs;
 	erts_system_profile_flags.exclusive = !!exclusive;
 	erts_system_profile_ts_type = ts;
-	erts_smp_thr_progress_unblock();
-	erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
+	erts_thr_progress_unblock();
+	erts_proc_lock(p, ERTS_PROC_LOCK_MAIN);
 	
 	BIF_RET(prev);
 		
@@ -2339,8 +2298,8 @@ BIF_RETTYPE system_profile_2(BIF_ALIST_2)
 
     error:
 	if (system_blocked) {
-	    erts_smp_thr_progress_unblock();
-	    erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
+	    erts_thr_progress_unblock();
+	    erts_proc_lock(p, ERTS_PROC_LOCK_MAIN);
     	}
 
     BIF_ERROR(p, BADARG);
@@ -2365,7 +2324,7 @@ typedef struct {
     Eterm ref;
     Eterm ref_heap[ERTS_REF_THING_SIZE];
     Eterm target;
-    erts_smp_atomic32_t refc;
+    erts_atomic32_t refc;
 } ErtsTraceDeliveredAll;
 
 static void
@@ -2373,31 +2332,20 @@ reply_trace_delivered_all(void *vtdarp)
 {
     ErtsTraceDeliveredAll *tdarp = (ErtsTraceDeliveredAll *) vtdarp;
 
-    if (erts_smp_atomic32_dec_read_nob(&tdarp->refc) == 0) {
+    if (erts_atomic32_dec_read_nob(&tdarp->refc) == 0) {
         Eterm ref_copy, msg;
         Process *rp = tdarp->proc;
         Eterm *hp = NULL;
         ErlOffHeap *ohp;
-#ifdef ERTS_SMP
         ErlHeapFragment *bp;
         bp = new_message_buffer(4 + NC_HEAP_SIZE(tdarp->ref));
         hp = &bp->mem[0];
         ohp = &bp->off_heap;
-#else
-        ErtsProcLocks rp_locks = 0;
-        ErtsMessage *mp;
-        mp = erts_alloc_message_heap(
-            rp, &rp_locks, 4 + NC_HEAP_SIZE(tdarp->ref), &hp, &ohp);
-#endif
 
         ref_copy = STORE_NC(&hp, ohp, tdarp->ref);
         msg = TUPLE3(hp, am_trace_delivered, tdarp->target, ref_copy);
 
-#ifdef ERTS_SMP
         erts_send_sys_msg_proc(rp->common.id, rp->common.id, msg, bp);
-#else
-        erts_queue_message(rp, rp_locks, mp, msg, am_system);
-#endif
 
 	erts_free(ERTS_ALC_T_MISC_AUX_WORK, vtdarp);
         erts_proc_dec_refc(rp);
@@ -2418,7 +2366,7 @@ trace_delivered_1(BIF_ALIST_1)
         hp = &tdarp->ref_heap[0];
         tdarp->ref = STORE_NC(&hp, NULL, ref);
         tdarp->target = BIF_ARG_1;
-        erts_smp_atomic32_init_nob(&tdarp->refc,
+        erts_atomic32_init_nob(&tdarp->refc,
                                    (erts_aint32_t) erts_no_schedulers);
         erts_proc_add_refc(BIF_P, 1);
         erts_schedule_multi_misc_aux_work(0,
diff --git a/erts/emulator/beam/erl_bif_unique.c b/erts/emulator/beam/erl_bif_unique.c
index 2f8adc87d5..19d46537f9 100644
--- a/erts/emulator/beam/erl_bif_unique.c
+++ b/erts/emulator/beam/erl_bif_unique.c
@@ -77,11 +77,9 @@ init_reference(void)
     ref_init_value += (Uint64) tv.tv_usec;
 #ifdef DEBUG
     max_thr_id = (Uint32) erts_no_schedulers;
-#ifdef ERTS_DIRTY_SCHEDULERS
     max_thr_id += (Uint32) erts_no_dirty_cpu_schedulers;
     max_thr_id += (Uint32) erts_no_dirty_io_schedulers;
 #endif
-#endif
     erts_atomic64_init_nob(&global_reference.count,
 			   (erts_aint64_t) ref_init_value);
     init_magic_ref_tables();
@@ -136,7 +134,7 @@ Eterm erts_make_ref(Process *c_p)
     Eterm* hp;
     Uint32 ref[ERTS_REF_NUMBERS];
 
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(c_p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(c_p));
 
     hp = HAlloc(c_p, ERTS_REF_THING_SIZE);
 
@@ -439,10 +437,8 @@ init_unique_integer(void)
 {
     int bits;
     unique_data.r.o.val0_max = (Uint64) erts_no_schedulers;
-#ifdef ERTS_DIRTY_SCHEDULERS
     unique_data.r.o.val0_max += (Uint64) erts_no_dirty_cpu_schedulers;
     unique_data.r.o.val0_max += (Uint64) erts_no_dirty_io_schedulers;
-#endif
     bits = erts_fit_in_bits_int64(unique_data.r.o.val0_max);
     unique_data.r.o.left_shift = bits;
     unique_data.r.o.right_shift = 64 - bits;
@@ -803,7 +799,7 @@ BIF_RETTYPE make_ref_0(BIF_ALIST_0)
     BIF_RETTYPE res;
     Eterm* hp;
 
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(BIF_P));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(BIF_P));
 
     hp = HAlloc(BIF_P, ERTS_REF_THING_SIZE);
 
diff --git a/erts/emulator/beam/erl_binary.h b/erts/emulator/beam/erl_binary.h
index b036b28dbf..46653a8580 100644
--- a/erts/emulator/beam/erl_binary.h
+++ b/erts/emulator/beam/erl_binary.h
@@ -291,7 +291,7 @@ typedef union {
      * atomics are used they might
      * differ in size.
      */
-    erts_smp_atomic_t smp_atomic_word;
+    erts_atomic_t smp_atomic_word;
     erts_atomic_t atomic_word;
 } ErtsMagicIndirectionWord;
 
@@ -326,7 +326,7 @@ ERTS_GLB_INLINE Binary *erts_create_magic_binary_x(Uint size,
 ERTS_GLB_INLINE Binary *erts_create_magic_binary(Uint size,
 						 int (*destructor)(Binary *));
 ERTS_GLB_INLINE Binary *erts_create_magic_indirection(int (*destructor)(Binary *));
-ERTS_GLB_INLINE erts_smp_atomic_t *erts_smp_binary_to_magic_indirection(Binary *bp);
+ERTS_GLB_INLINE erts_atomic_t *erts_binary_to_magic_indirection(Binary *bp);
 ERTS_GLB_INLINE erts_atomic_t *erts_binary_to_magic_indirection(Binary *bp);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
@@ -363,8 +363,6 @@ erts_free_aligned_binary_bytes(byte* buf)
 #  define CHICKEN_PAD (sizeof(void*) - 1)
 #endif
 
-/* Caller must initialize 'refc'
-*/
 ERTS_GLB_INLINE Binary *
 erts_bin_drv_alloc_fnf(Uint size)
 {
@@ -383,8 +381,6 @@ erts_bin_drv_alloc_fnf(Uint size)
     return res;
 }
 
-/* Caller must initialize 'refc'
-*/
 ERTS_GLB_INLINE Binary *
 erts_bin_drv_alloc(Uint size)
 {
@@ -401,9 +397,6 @@ erts_bin_drv_alloc(Uint size)
     return res;
 }
 
-
-/* Caller must initialize 'refc'
-*/
 ERTS_GLB_INLINE Binary *
 erts_bin_nrml_alloc(Uint size)
 {
@@ -519,16 +512,6 @@ erts_create_magic_indirection(int (*destructor)(Binary *))
                                              but word aligned */
 }
 
-ERTS_GLB_INLINE erts_smp_atomic_t *
-erts_smp_binary_to_magic_indirection(Binary *bp)
-{
-    ErtsMagicIndirectionWord *mip;
-    ASSERT(bp->intern.flags & BIN_FLAG_MAGIC);
-    ASSERT(ERTS_MAGIC_BIN_ATYPE(bp) == ERTS_ALC_T_MINDIRECTION);
-    mip = ERTS_MAGIC_BIN_UNALIGNED_DATA(bp);
-    return &mip->smp_atomic_word;
-}
-
 ERTS_GLB_INLINE erts_atomic_t *
 erts_binary_to_magic_indirection(Binary *bp)
 {
@@ -536,7 +519,7 @@ erts_binary_to_magic_indirection(Binary *bp)
     ASSERT(bp->intern.flags & BIN_FLAG_MAGIC);
     ASSERT(ERTS_MAGIC_BIN_ATYPE(bp) == ERTS_ALC_T_MINDIRECTION);
     mip = ERTS_MAGIC_BIN_UNALIGNED_DATA(bp);
-    return &mip->atomic_word;
+    return &mip->smp_atomic_word;
 }
 
 #endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
diff --git a/erts/emulator/beam/erl_bits.c b/erts/emulator/beam/erl_bits.c
index 51d23a8965..3a16913473 100644
--- a/erts/emulator/beam/erl_bits.c
+++ b/erts/emulator/beam/erl_bits.c
@@ -55,30 +55,19 @@
 
 static byte get_bit(byte b, size_t a_offs); 
 
-#if defined(ERTS_SMP)
 /* the state resides in the current process' scheduler data */
-#elif defined(ERL_BITS_REENTRANT)
-/* reentrant API but with a hidden single global state, for testing only */
-struct erl_bits_state ErlBitsState_;
-#else
-/* non-reentrant API with a single global state */
-struct erl_bits_state ErlBitsState;
-#endif
 
 #define byte_buf	(ErlBitsState.byte_buf_)
 #define byte_buf_len	(ErlBitsState.byte_buf_len_)
 
-static erts_smp_atomic_t bits_bufs_size;
+static erts_atomic_t bits_bufs_size;
 
 Uint
 erts_bits_bufs_size(void)
 {
-    return (Uint) erts_smp_atomic_read_nob(&bits_bufs_size);
+    return (Uint) erts_atomic_read_nob(&bits_bufs_size);
 }
 
-#if !defined(ERTS_SMP)
-static
-#endif
 void
 erts_bits_init_state(ERL_BITS_PROTO_0)
 {
@@ -88,13 +77,11 @@ erts_bits_init_state(ERL_BITS_PROTO_0)
     erts_bin_offset = 0;
 }
 
-#if defined(ERTS_SMP)
 void
 erts_bits_destroy_state(ERL_BITS_PROTO_0)
 {
     erts_free(ERTS_ALC_T_BITS_BUF, byte_buf);
 }
-#endif
 
 void
 erts_init_bits(void)
@@ -104,13 +91,8 @@ erts_init_bits(void)
     ERTS_CT_ASSERT(offsetof(ErtsBinary,driver.binary.orig_bytes)
                 == offsetof(Binary,orig_bytes));
 
-    erts_smp_atomic_init_nob(&bits_bufs_size, 0);
-#if defined(ERTS_SMP)
+    erts_atomic_init_nob(&bits_bufs_size, 0);
     /* erl_process.c calls erts_bits_init_state() on all state instances */
-#else
-    ERL_BITS_DECLARE_STATEP;
-    erts_bits_init_state(ERL_BITS_ARGS_0);
-#endif
 }
 
 /*****************************************************************
@@ -744,7 +726,7 @@ static void
 ERTS_INLINE need_byte_buf(ERL_BITS_PROTO_1(int need))
 {
     if (byte_buf_len < need) {
-	erts_smp_atomic_add_nob(&bits_bufs_size, need - byte_buf_len);
+	erts_atomic_add_nob(&bits_bufs_size, need - byte_buf_len);
 	byte_buf_len = need;
 	byte_buf = erts_realloc(ERTS_ALC_T_BITS_BUF, byte_buf, byte_buf_len);
     }
diff --git a/erts/emulator/beam/erl_bits.h b/erts/emulator/beam/erl_bits.h
index 5da2b28a89..b9d141d585 100644
--- a/erts/emulator/beam/erl_bits.h
+++ b/erts/emulator/beam/erl_bits.h
@@ -84,31 +84,14 @@ typedef struct erl_bin_match_struct{
 #define ms_matchbuffer(_Ms) &(((ErlBinMatchState*) boxed_val(_Ms))->mb)
 
 
-#if defined(ERTS_SMP)
-#define ERL_BITS_REENTRANT
-#else
-/* uncomment to test the reentrant API in the non-SMP runtime system */
-/* #define ERL_BITS_REENTRANT */
-#endif
-
-#ifdef ERL_BITS_REENTRANT
-
 /*
  * Reentrant API with the state passed as a parameter.
  * (Except when the current Process* already is a parameter.)
  */
-#ifdef ERTS_SMP
 /* the state resides in the current process' scheduler data */
 #define ERL_BITS_DECLARE_STATEP			struct erl_bits_state *EBS
 #define ERL_BITS_RELOAD_STATEP(P)		do{EBS = &erts_proc_sched_data((P))->erl_bits_state;}while(0)
 #define ERL_BITS_DEFINE_STATEP(P)		struct erl_bits_state *EBS = &erts_proc_sched_data((P))->erl_bits_state
-#else
-/* reentrant API but with a hidden single global state, for testing only */
-extern struct erl_bits_state ErlBitsState_;
-#define ERL_BITS_DECLARE_STATEP			struct erl_bits_state *EBS = &ErlBitsState_
-#define ERL_BITS_RELOAD_STATEP(P)		do{}while(0)
-#define ERL_BITS_DEFINE_STATEP(P)		ERL_BITS_DECLARE_STATEP
-#endif
 #define ErlBitsState				(*EBS)
 
 #define ERL_BITS_PROTO_0			struct erl_bits_state *EBS
@@ -120,26 +103,6 @@ extern struct erl_bits_state ErlBitsState_;
 #define ERL_BITS_ARGS_2(ARG1,ARG2)		EBS, ARG1, ARG2
 #define ERL_BITS_ARGS_3(ARG1,ARG2,ARG3)		EBS, ARG1, ARG2, ARG3
 
-#else	/* ERL_BITS_REENTRANT */
-
-/*
- * Non-reentrant API with a single global state.
- */
-extern struct erl_bits_state ErlBitsState;
-#define ERL_BITS_DECLARE_STATEP			/*empty*/
-#define ERL_BITS_RELOAD_STATEP(P)		do{}while(0)
-#define ERL_BITS_DEFINE_STATEP(P)		/*empty*/
-
-#define ERL_BITS_PROTO_0			void
-#define ERL_BITS_PROTO_1(PARM1)			PARM1
-#define ERL_BITS_PROTO_2(PARM1,PARM2)		PARM1, PARM2
-#define ERL_BITS_PROTO_3(PARM1,PARM2,PARM3)	PARM1, PARM2, PARM3
-#define ERL_BITS_ARGS_0				/*empty*/
-#define ERL_BITS_ARGS_1(ARG1)			ARG1
-#define ERL_BITS_ARGS_2(ARG1,ARG2)		ARG1, ARG2
-#define ERL_BITS_ARGS_3(ARG1,ARG2,ARG3)		ARG1, ARG2, ARG3
-
-#endif	/* ERL_BITS_REENTRANT */
 
 #define erts_bin_offset		(ErlBitsState.erts_bin_offset_)
 #define erts_current_bin	(ErlBitsState.erts_current_bin_)
@@ -158,10 +121,8 @@ extern struct erl_bits_state ErlBitsState;
   }  while (0)
 
 void erts_init_bits(void);	/* Initialization once. */
-#ifdef ERTS_SMP
 void erts_bits_init_state(ERL_BITS_PROTO_0);
 void erts_bits_destroy_state(ERL_BITS_PROTO_0);
-#endif
 
 
 /*
diff --git a/erts/emulator/beam/erl_cpu_topology.c b/erts/emulator/beam/erl_cpu_topology.c
index dfe49ce382..6f8d2f8c35 100644
--- a/erts/emulator/beam/erl_cpu_topology.c
+++ b/erts/emulator/beam/erl_cpu_topology.c
@@ -60,7 +60,7 @@ static int max_main_threads;
 static int reader_groups;
 
 static ErtsCpuBindData *scheduler2cpu_map;
-static erts_smp_rwmtx_t cpuinfo_rwmtx;
+static erts_rwmtx_t cpuinfo_rwmtx;
 
 typedef enum {
     ERTS_CPU_BIND_UNDEFINED,
@@ -131,13 +131,11 @@ static erts_cpu_groups_map_t *reader_groups_map;
 
 #define ERTS_MAX_CPU_TOPOLOGY_ID ((int) 0xffff)
 
-#ifdef ERTS_SMP
 static void cpu_bind_order_sort(erts_cpu_topology_t *cpudata,
 				int size,
 				ErtsCpuBindOrder bind_order,
 				int mk_seq);
 static void write_schedulers_bind_change(erts_cpu_topology_t *cpudata, int size);
-#endif
 
 static void reader_groups_callback(int, ErtsSchedulerData *, int, void *);
 static erts_cpu_groups_map_t *add_cpu_groups(int groups,
@@ -434,7 +432,6 @@ processor_order_cmp(const void *vx, const void *vy)
     return 0;
 }
 
-#ifdef ERTS_SMP
 void
 erts_sched_check_cpu_bind_prep_suspend(ErtsSchedulerData *esdp)
 {
@@ -444,7 +441,7 @@ erts_sched_check_cpu_bind_prep_suspend(ErtsSchedulerData *esdp)
     int cgcc_ix;
 
     /* Unbind from cpu */
-    erts_smp_rwmtx_rwlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rwlock(&cpuinfo_rwmtx);
     if (scheduler2cpu_map[esdp->no].bound_id >= 0
 	&& erts_unbind_from_cpu(cpuinfo) == 0) {
 	esdp->cpu_id = scheduler2cpu_map[esdp->no].bound_id = -1;
@@ -463,7 +460,7 @@ erts_sched_check_cpu_bind_prep_suspend(ErtsSchedulerData *esdp)
 	}
     }
     ASSERT(no_cpu_groups_callbacks == cgcc_ix);
-    erts_smp_rwmtx_rwunlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rwunlock(&cpuinfo_rwmtx);
 
     for (cgcc_ix = 0; cgcc_ix < no_cpu_groups_callbacks; cgcc_ix++)
 	cgcc[cgcc_ix].callback(1,
@@ -481,7 +478,7 @@ erts_sched_check_cpu_bind_prep_suspend(ErtsSchedulerData *esdp)
 void
 erts_sched_check_cpu_bind_post_suspend(ErtsSchedulerData *esdp)
 {
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(esdp->run_queue));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(esdp->run_queue));
 
     if (esdp->no <= max_main_threads)
 	erts_thr_set_main_status(1, (int) esdp->no);
@@ -490,7 +487,6 @@ erts_sched_check_cpu_bind_post_suspend(ErtsSchedulerData *esdp)
     (void) ERTS_RUNQ_FLGS_SET(esdp->run_queue, ERTS_RUNQ_FLG_CHK_CPU_BIND);
 }
 
-#endif
 
 void
 erts_sched_check_cpu_bind(ErtsSchedulerData *esdp)
@@ -499,8 +495,8 @@ erts_sched_check_cpu_bind(ErtsSchedulerData *esdp)
     erts_cpu_groups_map_t *cgm;
     erts_cpu_groups_callback_list_t *cgcl;
     erts_cpu_groups_callback_call_t *cgcc;
-    erts_smp_runq_unlock(esdp->run_queue);
-    erts_smp_rwmtx_rwlock(&cpuinfo_rwmtx);
+    erts_runq_unlock(esdp->run_queue);
+    erts_rwmtx_rwlock(&cpuinfo_rwmtx);
     cpu_id = scheduler2cpu_map[esdp->no].bind_id;
     if (cpu_id >= 0 && cpu_id != scheduler2cpu_map[esdp->no].bound_id) {
 	res = erts_bind_to_cpu(cpuinfo, cpu_id);
@@ -543,7 +539,7 @@ erts_sched_check_cpu_bind(ErtsSchedulerData *esdp)
     }
 
     ASSERT(no_cpu_groups_callbacks == cgcc_ix);
-    erts_smp_rwmtx_rwunlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rwunlock(&cpuinfo_rwmtx);
 
     for (cgcc_ix = 0; cgcc_ix < no_cpu_groups_callbacks; cgcc_ix++)
 	cgcc[cgcc_ix].callback(0,
@@ -553,10 +549,9 @@ erts_sched_check_cpu_bind(ErtsSchedulerData *esdp)
 
     erts_free(ERTS_ALC_T_TMP, cgcc);
 
-    erts_smp_runq_lock(esdp->run_queue);
+    erts_runq_lock(esdp->run_queue);
 }
 
-#ifdef ERTS_SMP
 void
 erts_sched_init_check_cpu_bind(ErtsSchedulerData *esdp)
 {
@@ -565,7 +560,7 @@ erts_sched_init_check_cpu_bind(ErtsSchedulerData *esdp)
     erts_cpu_groups_callback_list_t *cgcl;
     erts_cpu_groups_callback_call_t *cgcc;
 
-    erts_smp_rwmtx_rlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rlock(&cpuinfo_rwmtx);
 
     cgcc = erts_alloc(ERTS_ALC_T_TMP,
 		      (no_cpu_groups_callbacks
@@ -581,7 +576,7 @@ erts_sched_init_check_cpu_bind(ErtsSchedulerData *esdp)
     }
 
     ASSERT(no_cpu_groups_callbacks == cgcc_ix);
-    erts_smp_rwmtx_runlock(&cpuinfo_rwmtx);
+    erts_rwmtx_runlock(&cpuinfo_rwmtx);
 
     for (cgcc_ix = 0; cgcc_ix < no_cpu_groups_callbacks; cgcc_ix++)
 	cgcc[cgcc_ix].callback(0,
@@ -594,7 +589,6 @@ erts_sched_init_check_cpu_bind(ErtsSchedulerData *esdp)
     if (esdp->no <= max_main_threads)
 	erts_thr_set_main_status(1, (int) esdp->no);
 }
-#endif
 
 static void
 write_schedulers_bind_change(erts_cpu_topology_t *cpudata, int size)
@@ -602,7 +596,7 @@ write_schedulers_bind_change(erts_cpu_topology_t *cpudata, int size)
     int s_ix = 1;
     int cpu_ix;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(&cpuinfo_rwmtx));
+    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(&cpuinfo_rwmtx));
 
     if (cpu_bind_order != ERTS_CPU_BIND_NONE && size) {
 
@@ -702,9 +696,9 @@ Eterm
 erts_bound_schedulers_term(Process *c_p)
 {
     ErtsCpuBindOrder order;
-    erts_smp_rwmtx_rlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rlock(&cpuinfo_rwmtx);
     order = cpu_bind_order;
-    erts_smp_rwmtx_runlock(&cpuinfo_rwmtx);
+    erts_rwmtx_runlock(&cpuinfo_rwmtx);
     return bound_schedulers_term(order);
 }
 
@@ -717,7 +711,7 @@ erts_bind_schedulers(Process *c_p, Eterm how)
     int cpudata_size;
     ErtsCpuBindOrder old_cpu_bind_order;
 
-    erts_smp_rwmtx_rwlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rwlock(&cpuinfo_rwmtx);
 
     if (erts_bind_to_cpu(cpuinfo, -1) == -ENOTSUP) {
 	if (cpu_bind_order == ERTS_CPU_BIND_NONE
@@ -773,7 +767,7 @@ erts_bind_schedulers(Process *c_p, Eterm how)
 
  done:
 
-    erts_smp_rwmtx_rwunlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rwunlock(&cpuinfo_rwmtx);
 
     if (notify)
 	erts_sched_notify_check_cpu_bind();
@@ -793,9 +787,9 @@ erts_sched_bind_atthrcreate_child(int unbind)
 {
     int res = 0;
     if (unbind) {
-	erts_smp_rwmtx_rlock(&cpuinfo_rwmtx);
+	erts_rwmtx_rlock(&cpuinfo_rwmtx);
 	res = erts_unbind_from_cpu(cpuinfo);
-	erts_smp_rwmtx_runlock(&cpuinfo_rwmtx);
+	erts_rwmtx_runlock(&cpuinfo_rwmtx);
     }
     return res;
 }
@@ -812,7 +806,7 @@ erts_sched_bind_atfork_prepare(void)
     ErtsSchedulerData *esdp = erts_get_scheduler_data();
     int unbind = esdp != NULL && erts_is_scheduler_bound(esdp);
     if (unbind)
-	erts_smp_rwmtx_rlock(&cpuinfo_rwmtx);
+	erts_rwmtx_rlock(&cpuinfo_rwmtx);
     return unbind;
 }
 
@@ -820,7 +814,7 @@ int
 erts_sched_bind_atfork_child(int unbind)
 {
     if (unbind) {
-	ERTS_SMP_LC_ASSERT(erts_lc_rwmtx_is_rlocked(&cpuinfo_rwmtx)
+	ERTS_LC_ASSERT(erts_lc_rwmtx_is_rlocked(&cpuinfo_rwmtx)
 			   || erts_lc_rwmtx_is_rwlocked(&cpuinfo_rwmtx));
 	return erts_unbind_from_cpu(cpuinfo);
     }
@@ -831,7 +825,7 @@ void
 erts_sched_bind_atfork_parent(int unbind)
 {
     if (unbind)
-	erts_smp_rwmtx_runlock(&cpuinfo_rwmtx);
+	erts_rwmtx_runlock(&cpuinfo_rwmtx);
 }
 
 Eterm
@@ -865,9 +859,9 @@ erts_fake_scheduler_bindings(Process *p, Eterm how)
 	return res;
     }
 
-    erts_smp_rwmtx_rlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rlock(&cpuinfo_rwmtx);
     create_tmp_cpu_topology_copy(&cpudata, &cpudata_size);
-    erts_smp_rwmtx_runlock(&cpuinfo_rwmtx);
+    erts_rwmtx_runlock(&cpuinfo_rwmtx);
 
     if (!cpudata || fake_cpu_bind_order == ERTS_CPU_BIND_NONE)
 	ERTS_BIF_PREP_RET(res, am_false);
@@ -930,12 +924,12 @@ erts_get_schedulers_binds(Process *c_p)
     Eterm res = make_tuple(hp);
 
     *(hp++) = make_arityval(erts_no_schedulers);
-    erts_smp_rwmtx_rlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rlock(&cpuinfo_rwmtx);
     for (ix = 1; ix <= erts_no_schedulers; ix++)
 	*(hp++) = (scheduler2cpu_map[ix].bound_id >= 0
 		   ? make_small(scheduler2cpu_map[ix].bound_id)
 		   : AM_unbound);
-    erts_smp_rwmtx_runlock(&cpuinfo_rwmtx);
+    erts_rwmtx_runlock(&cpuinfo_rwmtx);
     return res;
 }
 
@@ -1346,7 +1340,7 @@ erts_set_cpu_topology(Process *c_p, Eterm term)
     int cpudata_size = 0;
     Eterm res;
 
-    erts_smp_rwmtx_rwlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rwlock(&cpuinfo_rwmtx);
     res = get_cpu_topology_term(c_p, ERTS_GET_USED_CPU_TOPOLOGY);
     if (term == am_undefined) {
 	if (user_cpudata)
@@ -1367,7 +1361,7 @@ erts_set_cpu_topology(Process *c_p, Eterm term)
     }
     else if (is_not_list(term)) {
     error:
-	erts_smp_rwmtx_rwunlock(&cpuinfo_rwmtx);
+	erts_rwmtx_rwunlock(&cpuinfo_rwmtx);
 	res = THE_NON_VALUE;
 	goto done;
     }
@@ -1461,7 +1455,7 @@ erts_set_cpu_topology(Process *c_p, Eterm term)
 
     write_schedulers_bind_change(cpudata, cpudata_size);
 
-    erts_smp_rwmtx_rwunlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rwunlock(&cpuinfo_rwmtx);
     erts_sched_notify_check_cpu_bind();
 
  done:
@@ -1615,7 +1609,7 @@ erts_get_cpu_topology_term(Process *c_p, Eterm which)
 {
     Eterm res;
     int type;
-    erts_smp_rwmtx_rlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rlock(&cpuinfo_rwmtx);
     if (ERTS_IS_ATOM_STR("used", which))
 	type = ERTS_GET_USED_CPU_TOPOLOGY;
     else if (ERTS_IS_ATOM_STR("detected", which))
@@ -1628,7 +1622,7 @@ erts_get_cpu_topology_term(Process *c_p, Eterm which)
 	res = THE_NON_VALUE;
     else
 	res = get_cpu_topology_term(c_p, type);
-    erts_smp_rwmtx_runlock(&cpuinfo_rwmtx);
+    erts_rwmtx_runlock(&cpuinfo_rwmtx);
     return res;
 }
 
@@ -1646,9 +1640,9 @@ get_logical_processors(int *conf, int *onln, int *avail)
 void
 erts_get_logical_processors(int *conf, int *onln, int *avail)
 {
-    erts_smp_rwmtx_rlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rlock(&cpuinfo_rwmtx);
     get_logical_processors(conf, onln, avail);
-    erts_smp_rwmtx_runlock(&cpuinfo_rwmtx);
+    erts_rwmtx_runlock(&cpuinfo_rwmtx);
 }
 
 void
@@ -1706,9 +1700,9 @@ erts_init_cpu_topology(void)
 {
     int ix;
 
-    erts_smp_rwmtx_init(&cpuinfo_rwmtx, "cpu_info", NIL,
+    erts_rwmtx_init(&cpuinfo_rwmtx, "cpu_info", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
-    erts_smp_rwmtx_rwlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rwlock(&cpuinfo_rwmtx);
 
     scheduler2cpu_map = erts_alloc(ERTS_ALC_T_CPUDATA,
 				   (sizeof(ErtsCpuBindData)
@@ -1726,13 +1720,13 @@ erts_init_cpu_topology(void)
 				       NULL);
 
     if (cpu_bind_order == ERTS_CPU_BIND_NONE)
-	erts_smp_rwmtx_rwunlock(&cpuinfo_rwmtx);
+	erts_rwmtx_rwunlock(&cpuinfo_rwmtx);
     else {
 	erts_cpu_topology_t *cpudata;
 	int cpudata_size;
 	create_tmp_cpu_topology_copy(&cpudata, &cpudata_size);
 	write_schedulers_bind_change(cpudata, cpudata_size);
-	erts_smp_rwmtx_rwunlock(&cpuinfo_rwmtx);
+	erts_rwmtx_rwunlock(&cpuinfo_rwmtx);
 	erts_sched_notify_check_cpu_bind();
 	destroy_tmp_cpu_topology_copy(cpudata);
     }
@@ -1742,7 +1736,7 @@ int
 erts_update_cpu_info(void)
 {
     int changed;
-    erts_smp_rwmtx_rwlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rwlock(&cpuinfo_rwmtx);
     changed = erts_cpu_info_update(cpuinfo);
     if (changed) {
 	erts_cpu_topology_t *cpudata;
@@ -1775,7 +1769,7 @@ erts_update_cpu_info(void)
 	write_schedulers_bind_change(cpudata, cpudata_size);
 	destroy_tmp_cpu_topology_copy(cpudata);
     }
-    erts_smp_rwmtx_rwunlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rwunlock(&cpuinfo_rwmtx);
     if (changed)
 	erts_sched_notify_check_cpu_bind();
     return changed;
@@ -1792,7 +1786,7 @@ reader_groups_callback(int suspending,
 		       void *unused)
 {
     if (reader_groups && esdp->no <= max_main_threads)
-	erts_smp_rwmtx_set_reader_group(suspending ? 0 : group+1);
+	erts_rwmtx_set_reader_group(suspending ? 0 : group+1);
 }
 
 static Eterm get_cpu_groups_map(Process *c_p,
@@ -1821,9 +1815,9 @@ Eterm
 erts_get_reader_groups_map(Process *c_p)
 {
     Eterm res;
-    erts_smp_rwmtx_rlock(&cpuinfo_rwmtx);
+    erts_rwmtx_rlock(&cpuinfo_rwmtx);
     res = get_cpu_groups_map(c_p, reader_groups_map, 1);
-    erts_smp_rwmtx_runlock(&cpuinfo_rwmtx);
+    erts_rwmtx_runlock(&cpuinfo_rwmtx);
     return res;
 }
 
@@ -2203,7 +2197,7 @@ add_cpu_groups(int groups,
     erts_cpu_groups_callback_list_t *cgcl;
     erts_cpu_groups_map_t *cgm;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(&cpuinfo_rwmtx));
+    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(&cpuinfo_rwmtx));
 
     if (use_groups > max_main_threads)
 	use_groups = max_main_threads;
@@ -2250,7 +2244,7 @@ cpu_groups_lookup(erts_cpu_groups_map_t *map,
 {
     int start, logical, ix;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_rwmtx_is_rlocked(&cpuinfo_rwmtx)
+    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rlocked(&cpuinfo_rwmtx)
 		       || erts_lc_rwmtx_is_rwlocked(&cpuinfo_rwmtx));
 
     if (esdp->cpu_id < 0)
@@ -2278,7 +2272,7 @@ static void
 update_cpu_groups_maps(void)
 {
     erts_cpu_groups_map_t *cgm;
-    ERTS_SMP_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(&cpuinfo_rwmtx));
+    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(&cpuinfo_rwmtx));
 
     for (cgm = cpu_groups_maps; cgm; cgm = cgm->next)
 	make_cpu_groups_map(cgm, 0);
diff --git a/erts/emulator/beam/erl_cpu_topology.h b/erts/emulator/beam/erl_cpu_topology.h
index c922214702..88bcad79ab 100644
--- a/erts/emulator/beam/erl_cpu_topology.h
+++ b/erts/emulator/beam/erl_cpu_topology.h
@@ -60,11 +60,9 @@ int erts_init_scheduler_bind_type_string(char *how);
 int erts_init_cpu_topology_string(char *topology_str);
 
 void erts_sched_check_cpu_bind(ErtsSchedulerData *esdp);
-#ifdef ERTS_SMP
 void erts_sched_init_check_cpu_bind(ErtsSchedulerData *esdp);
 void erts_sched_check_cpu_bind_prep_suspend(ErtsSchedulerData *esdp);
 void erts_sched_check_cpu_bind_post_suspend(ErtsSchedulerData *esdp);
-#endif
 
 int erts_update_cpu_info(void);
 
diff --git a/erts/emulator/beam/erl_db.c b/erts/emulator/beam/erl_db.c
index 6d4a895ef6..3ba0886464 100644
--- a/erts/emulator/beam/erl_db.c
+++ b/erts/emulator/beam/erl_db.c
@@ -44,7 +44,7 @@
 #include "erl_binary.h"
 
 
-erts_smp_atomic_t erts_ets_misc_mem_size;
+erts_atomic_t erts_ets_misc_mem_size;
 
 /*
 ** Utility macros
@@ -61,15 +61,9 @@ enum DbIterSafety {
     ITER_SAFE_LOCKED, /* Safe while table is locked, not between trap calls */
     ITER_SAFE         /* No need to fixate at all */
 };
-#ifdef ERTS_SMP
 #  define ITERATION_SAFETY(Proc,Tab) \
     ((IS_TREE_TABLE((Tab)->common.status) || ONLY_WRITER(Proc,Tab)) ? ITER_SAFE \
      : (((Tab)->common.status & DB_FINE_LOCKED) ? ITER_UNSAFE : ITER_SAFE_LOCKED))
-#else
-#  define ITERATION_SAFETY(Proc,Tab) \
-    ((IS_TREE_TABLE((Tab)->common.status) || ONLY_WRITER(Proc,Tab)) \
-     ? ITER_SAFE : ITER_SAFE_LOCKED)
-#endif
 
 #define DID_TRAP(P,Ret) (!is_value(Ret) && ((P)->freason == TRAP))
 
@@ -195,7 +189,7 @@ static void delete_sched_table(Process *c_p, DbTable *tb);
 
 static void table_dec_refc(DbTable *tb, erts_aint_t min_val)
 {
-    if (erts_smp_refc_dectest(&tb->common.refc, min_val) == 0)
+    if (erts_refc_dectest(&tb->common.refc, min_val) == 0)
 	schedule_free_dbtable(tb);
 }
 
@@ -209,21 +203,21 @@ static ERTS_INLINE void
 make_btid(DbTable *tb)
 {
     Binary *btid = erts_create_magic_indirection(db_table_tid_destructor);
-    erts_smp_atomic_t *tbref = erts_smp_binary_to_magic_indirection(btid);
-    erts_smp_atomic_init_nob(tbref, (erts_aint_t) tb);
+    erts_atomic_t *tbref = erts_binary_to_magic_indirection(btid);
+    erts_atomic_init_nob(tbref, (erts_aint_t) tb);
     tb->common.btid = btid;
     /*
      * Table and magic indirection refer eachother,
      * and table is refered once by being alive...
      */
-    erts_smp_refc_init(&tb->common.refc, 2);
+    erts_refc_init(&tb->common.refc, 2);
     erts_refc_inc(&btid->intern.refc, 1);
 }
 
 static ERTS_INLINE DbTable* btid2tab(Binary* btid)
 {
-    erts_smp_atomic_t *tbref = erts_smp_binary_to_magic_indirection(btid);
-    return (DbTable *) erts_smp_atomic_read_nob(tbref);
+    erts_atomic_t *tbref = erts_binary_to_magic_indirection(btid);
+    return (DbTable *) erts_atomic_read_nob(tbref);
 }
 
 static DbTable *
@@ -231,7 +225,7 @@ tid2tab(Eterm tid)
 {
     DbTable *tb;
     Binary *btid;
-    erts_smp_atomic_t *tbref;
+    erts_atomic_t *tbref;
     if (!is_internal_magic_ref(tid))
         return NULL;
 
@@ -239,8 +233,8 @@ tid2tab(Eterm tid)
     if (ERTS_MAGIC_BIN_DESTRUCTOR(btid) != db_table_tid_destructor)
         return NULL;
 
-    tbref = erts_smp_binary_to_magic_indirection(btid);
-    tb = (DbTable *) erts_smp_atomic_read_nob(tbref);
+    tbref = erts_binary_to_magic_indirection(btid);
+    tb = (DbTable *) erts_atomic_read_nob(tbref);
 
     ASSERT(!tb || tb->common.btid == btid);
 
@@ -250,11 +244,11 @@ tid2tab(Eterm tid)
 static ERTS_INLINE int
 is_table_alive(DbTable *tb)
 {
-    erts_smp_atomic_t *tbref;
+    erts_atomic_t *tbref;
     DbTable *rtb;
 
-    tbref = erts_smp_binary_to_magic_indirection(tb->common.btid);
-    rtb = (DbTable *) erts_smp_atomic_read_nob(tbref);
+    tbref = erts_binary_to_magic_indirection(tb->common.btid);
+    rtb = (DbTable *) erts_atomic_read_nob(tbref);
 
     ASSERT(!rtb || rtb == tb);
 
@@ -264,11 +258,7 @@ is_table_alive(DbTable *tb)
 static ERTS_INLINE int
 is_table_named(DbTable *tb)
 {
-#ifdef ERTS_SMP
     return tb->common.type & DB_NAMED_TABLE;
-#else
-    return tb->common.status & DB_NAMED_TABLE;
-#endif
 }
 
 
@@ -277,8 +267,8 @@ tid_clear(Process *c_p, DbTable *tb)
 {
     DbTable *rtb;
     Binary *btid = tb->common.btid;
-    erts_smp_atomic_t *tbref = erts_smp_binary_to_magic_indirection(btid);
-    rtb = (DbTable *) erts_smp_atomic_xchg_nob(tbref, (erts_aint_t) NULL);
+    erts_atomic_t *tbref = erts_binary_to_magic_indirection(btid);
+    rtb = (DbTable *) erts_atomic_xchg_nob(tbref, (erts_aint_t) NULL);
     ASSERT(!rtb || tb == rtb);
     if (rtb) {
         table_dec_refc(tb, 1);
@@ -297,13 +287,11 @@ make_tid(Process *c_p, DbTable *tb)
 /* 
 ** The meta hash table of all NAMED ets tables
 */
-#ifdef ERTS_SMP
 #  define META_NAME_TAB_LOCK_CNT 16
 union {
-    erts_smp_rwmtx_t lck;
+    erts_rwmtx_t lck;
     byte _cache_line_alignment[64];
 }meta_name_tab_rwlocks[META_NAME_TAB_LOCK_CNT];
-#endif
 static struct meta_name_tab_entry {
     union {
 	Eterm name_atom;
@@ -319,13 +307,11 @@ static unsigned meta_name_tab_mask;
 
 static ERTS_INLINE
 struct meta_name_tab_entry* meta_name_tab_bucket(Eterm name, 
-						 erts_smp_rwmtx_t** lockp)
+						 erts_rwmtx_t** lockp)
 {
     unsigned bix = atom_val(name) & meta_name_tab_mask;
     struct meta_name_tab_entry* bucket = &meta_name_tab[bix];
-#ifdef ERTS_SMP
     *lockp = &meta_name_tab_rwlocks[bix % META_NAME_TAB_LOCK_CNT].lck;
-#endif
     return bucket;
 }    
 
@@ -390,16 +376,14 @@ free_dbtable(void *vtb)
 {
     DbTable *tb = (DbTable *) vtb;
 #ifdef HARDDEBUG
-	if (erts_smp_atomic_read_nob(&tb->common.memory_size) != sizeof(DbTable)) {
+	if (erts_atomic_read_nob(&tb->common.memory_size) != sizeof(DbTable)) {
 	    erts_fprintf(stderr, "ets: free_dbtable memory remain=%ld fix=%x\n",
-			 erts_smp_atomic_read_nob(&tb->common.memory_size)-sizeof(DbTable),
+			 erts_atomic_read_nob(&tb->common.memory_size)-sizeof(DbTable),
 			 tb->common.fixations);
 	}
 #endif
-#ifdef ERTS_SMP
-	erts_smp_rwmtx_destroy(&tb->common.rwlock);
-	erts_smp_mtx_destroy(&tb->common.fixlock);
-#endif
+	erts_rwmtx_destroy(&tb->common.rwlock);
+	erts_mtx_destroy(&tb->common.fixlock);
 	ASSERT(is_immed(tb->common.heir_data));
 
         if (tb->common.btid)
@@ -419,8 +403,8 @@ static void schedule_free_dbtable(DbTable* tb)
      *  	     Caller is *not* allowed to access the specialized part
      *  	     (hash or tree) of *tb after this function has returned.
      */
-    ASSERT(erts_smp_refc_read(&tb->common.refc, 0) == 0);
-    ASSERT(erts_smp_refc_read(&tb->common.fix_count, 0) == 0);
+    ASSERT(erts_refc_read(&tb->common.refc, 0) == 0);
+    ASSERT(erts_refc_read(&tb->common.fix_count, 0) == 0);
     erts_schedule_thr_prgr_later_cleanup_op(free_dbtable,
 					    (void *) tb,
 					    &tb->release.data,
@@ -435,7 +419,7 @@ save_sched_table(Process *c_p, DbTable *tb)
 
     ASSERT(esdp);
     esdp->ets_tables.count++;
-    erts_smp_refc_inc(&tb->common.refc, 1);
+    erts_refc_inc(&tb->common.refc, 1);
 
     first = esdp->ets_tables.clist;
     if (!first) {
@@ -525,11 +509,11 @@ save_owned_table(Process *c_p, DbTable *tb)
 {
     DbTable *first;
 
-    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_lock(c_p, ERTS_PROC_LOCK_STATUS);
 
     first = (DbTable*) erts_psd_get(c_p, ERTS_PSD_ETS_OWNED_TABLES);
 
-    erts_smp_refc_inc(&tb->common.refc, 1);
+    erts_refc_inc(&tb->common.refc, 1);
 
     if (!first) {
         tb->common.owned.next = tb->common.owned.prev = tb;
@@ -541,13 +525,13 @@ save_owned_table(Process *c_p, DbTable *tb)
         tb->common.owned.prev->common.owned.next = tb;
         first->common.owned.prev = tb;
     }
-    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_unlock(c_p, ERTS_PROC_LOCK_STATUS);
 }
 
 static ERTS_INLINE void
 delete_owned_table(Process *p, DbTable *tb)
 {
-    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
     if (tb->common.owned.next == tb) {
         DbTable* old;
         ASSERT(tb->common.owned.prev == tb);
@@ -570,38 +554,33 @@ delete_owned_table(Process *p, DbTable *tb)
         if (tb == first)
             erts_psd_set(p, ERTS_PSD_ETS_OWNED_TABLES, tb->common.owned.next);
     }
-    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
 
     table_dec_refc(tb, 1);
 }
 
 static ERTS_INLINE void db_init_lock(DbTable* tb, int use_frequent_read_lock)
 {
-#ifdef ERTS_SMP
-    erts_smp_rwmtx_opt_t rwmtx_opt = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
+    erts_rwmtx_opt_t rwmtx_opt = ERTS_RWMTX_OPT_DEFAULT_INITER;
     if (use_frequent_read_lock)
-	rwmtx_opt.type = ERTS_SMP_RWMTX_TYPE_FREQUENT_READ;
+	rwmtx_opt.type = ERTS_RWMTX_TYPE_FREQUENT_READ;
     if (erts_ets_rwmtx_spin_count >= 0)
 	rwmtx_opt.main_spincount = erts_ets_rwmtx_spin_count;
-#endif
-#ifdef ERTS_SMP
-    erts_smp_rwmtx_init_opt(&tb->common.rwlock, &rwmtx_opt, "db_tab",
+    erts_rwmtx_init_opt(&tb->common.rwlock, &rwmtx_opt, "db_tab",
         tb->common.the_name, ERTS_LOCK_FLAGS_CATEGORY_DB);
-    erts_smp_mtx_init(&tb->common.fixlock, "db_tab_fix",
+    erts_mtx_init(&tb->common.fixlock, "db_tab_fix",
         tb->common.the_name, ERTS_LOCK_FLAGS_CATEGORY_DB);
     tb->common.is_thread_safe = !(tb->common.status & DB_FINE_LOCKED);
-#endif
 }
 
 static ERTS_INLINE void db_lock(DbTable* tb, db_lock_kind_t kind)
 {
-#ifdef ERTS_SMP
     if (tb->common.type & DB_FINE_LOCKED) {
 	if (kind == LCK_WRITE) {	   
-	    erts_smp_rwmtx_rwlock(&tb->common.rwlock);
+	    erts_rwmtx_rwlock(&tb->common.rwlock);
 	    tb->common.is_thread_safe = 1;
 	} else {	
-	    erts_smp_rwmtx_rlock(&tb->common.rwlock);
+	    erts_rwmtx_rlock(&tb->common.rwlock);
 	    ASSERT(!tb->common.is_thread_safe);
 	}
     }
@@ -610,14 +589,13 @@ static ERTS_INLINE void db_lock(DbTable* tb, db_lock_kind_t kind)
 	switch (kind) {
 	case LCK_WRITE:
 	case LCK_WRITE_REC:
-	    erts_smp_rwmtx_rwlock(&tb->common.rwlock);
+	    erts_rwmtx_rwlock(&tb->common.rwlock);
 	    break;
 	default:
-	    erts_smp_rwmtx_rlock(&tb->common.rwlock);
+	    erts_rwmtx_rlock(&tb->common.rwlock);
 	}
 	ASSERT(tb->common.is_thread_safe);
     }
-#endif
 }
 
 static ERTS_INLINE void db_unlock(DbTable* tb, db_lock_kind_t kind)
@@ -627,16 +605,15 @@ static ERTS_INLINE void db_unlock(DbTable* tb, db_lock_kind_t kind)
      * DbTable structure. That is, ONLY the SMP case is allowed
      * to follow the tb pointer!
      */
-#ifdef ERTS_SMP
     if (tb->common.type & DB_FINE_LOCKED) {
 	if (kind == LCK_WRITE) {
 	    ASSERT(tb->common.is_thread_safe);
 	    tb->common.is_thread_safe = 0;
-	    erts_smp_rwmtx_rwunlock(&tb->common.rwlock);
+	    erts_rwmtx_rwunlock(&tb->common.rwlock);
 	}
 	else {
 	    ASSERT(!tb->common.is_thread_safe);
-	    erts_smp_rwmtx_runlock(&tb->common.rwlock);
+	    erts_rwmtx_runlock(&tb->common.rwlock);
 	}
     }
     else {
@@ -644,13 +621,12 @@ static ERTS_INLINE void db_unlock(DbTable* tb, db_lock_kind_t kind)
 	switch (kind) {
 	case LCK_WRITE:
 	case LCK_WRITE_REC:
-	    erts_smp_rwmtx_rwunlock(&tb->common.rwlock);
+	    erts_rwmtx_rwunlock(&tb->common.rwlock);
 	    break;
 	default:
-	    erts_smp_rwmtx_runlock(&tb->common.rwlock);
+	    erts_rwmtx_runlock(&tb->common.rwlock);
 	}
     }
-#endif
 }
 
 static ERTS_INLINE
@@ -661,7 +637,7 @@ DbTable* db_get_table_aux(Process *p,
 			  int meta_already_locked)
 {
     DbTable *tb;
-    erts_smp_rwmtx_t *mtl = NULL;
+    erts_rwmtx_t *mtl = NULL;
 
     /*
      * IMPORTANT: Only scheduler threads are allowed
@@ -673,9 +649,9 @@ DbTable* db_get_table_aux(Process *p,
     if (is_atom(id)) {
 	struct meta_name_tab_entry* bucket = meta_name_tab_bucket(id,&mtl);
 	if (!meta_already_locked)
-	    erts_smp_rwmtx_rlock(mtl);
+	    erts_rwmtx_rlock(mtl);
 	else{
-	    ERTS_SMP_LC_ASSERT(erts_lc_rwmtx_is_rlocked(mtl)
+	    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rlocked(mtl)
 			       || erts_lc_rwmtx_is_rwlocked(mtl));
 	    mtl = NULL;
 	}
@@ -709,7 +685,7 @@ DbTable* db_get_table_aux(Process *p,
 	}
     }
     if (mtl)
-	erts_smp_rwmtx_runlock(mtl);
+	erts_rwmtx_runlock(mtl);
     return tb;
 }
 
@@ -725,12 +701,12 @@ DbTable* db_get_table(Process *p,
 static int insert_named_tab(Eterm name_atom, DbTable* tb, int have_lock)
 {
     int ret = 0;
-    erts_smp_rwmtx_t* rwlock;
+    erts_rwmtx_t* rwlock;
     struct meta_name_tab_entry* new_entry;
     struct meta_name_tab_entry* bucket = meta_name_tab_bucket(name_atom,
 							      &rwlock);
     if (!have_lock)
-	erts_smp_rwmtx_rwlock(rwlock);
+	erts_rwmtx_rwlock(rwlock);
 
     if (bucket->pu.tb == NULL) { /* empty */
 	new_entry = bucket;
@@ -778,27 +754,25 @@ static int insert_named_tab(Eterm name_atom, DbTable* tb, int have_lock)
 
 done:
     if (!have_lock)
-	erts_smp_rwmtx_rwunlock(rwlock);
+	erts_rwmtx_rwunlock(rwlock);
     return ret;
 }
 
 static int remove_named_tab(DbTable *tb, int have_lock)
 {
     int ret = 0;
-    erts_smp_rwmtx_t* rwlock;
+    erts_rwmtx_t* rwlock;
     Eterm name_atom = tb->common.the_name;
     struct meta_name_tab_entry* bucket = meta_name_tab_bucket(name_atom,
 							      &rwlock);
     ASSERT(is_table_named(tb));
-#ifdef ERTS_SMP
-    if (!have_lock && erts_smp_rwmtx_tryrwlock(rwlock) == EBUSY) {
+    if (!have_lock && erts_rwmtx_tryrwlock(rwlock) == EBUSY) {
 	db_unlock(tb, LCK_WRITE);
-	erts_smp_rwmtx_rwlock(rwlock);
+	erts_rwmtx_rwlock(rwlock);
 	db_lock(tb, LCK_WRITE);
     }
-#endif
 
-    ERTS_SMP_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(rwlock));
+    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(rwlock));
 
     if (bucket->pu.tb == NULL) {
 	goto done;
@@ -851,7 +825,7 @@ static int remove_named_tab(DbTable *tb, int have_lock)
 
 done:
     if (!have_lock)
-	erts_smp_rwmtx_rwunlock(rwlock);
+	erts_rwmtx_rwunlock(rwlock);
     return ret;
 }
 
@@ -860,11 +834,11 @@ done:
 */
 static ERTS_INLINE void local_fix_table(DbTable* tb)
 {
-    erts_smp_refc_inc(&tb->common.fix_count, 1);
+    erts_refc_inc(&tb->common.fix_count, 1);
 }	    
 static ERTS_INLINE void local_unfix_table(DbTable* tb)
 {	
-    if (erts_smp_refc_dectest(&tb->common.fix_count, 0) == 0) {
+    if (erts_refc_dectest(&tb->common.fix_count, 0) == 0) {
 	ASSERT(IS_HASH_TABLE(tb->common.status));
 	db_unfix_table_hash(&(tb->hash));
     }
@@ -1505,7 +1479,7 @@ BIF_RETTYPE ets_rename_2(BIF_ALIST_2)
     DbTable* tb;
     Eterm ret;
     Eterm old_name;
-    erts_smp_rwmtx_t *lck1, *lck2;
+    erts_rwmtx_t *lck1, *lck2;
 
 #ifdef HARDDEBUG
     erts_fprintf(stderr,
@@ -1528,7 +1502,7 @@ BIF_RETTYPE ets_rename_2(BIF_ALIST_2)
 	if (lck1 == lck2)
 	    lck2 = NULL;
 	else if (lck1 > lck2) {
-	    erts_smp_rwmtx_t *tmp = lck1;
+	    erts_rwmtx_t *tmp = lck1;
 	    lck1 = lck2;
 	    lck2 = tmp;
 	}
@@ -1546,9 +1520,9 @@ BIF_RETTYPE ets_rename_2(BIF_ALIST_2)
         }
     }
 
-    erts_smp_rwmtx_rwlock(lck1);
+    erts_rwmtx_rwlock(lck1);
     if (lck2)
-	erts_smp_rwmtx_rwlock(lck2);
+	erts_rwmtx_rwlock(lck2);
 
     tb = db_get_table_aux(BIF_P, BIF_ARG_1, DB_WRITE, LCK_WRITE, 1);
     if (!tb)
@@ -1568,16 +1542,16 @@ BIF_RETTYPE ets_rename_2(BIF_ALIST_2)
     tb->common.the_name = BIF_ARG_2;
 
     db_unlock(tb, LCK_WRITE);
-    erts_smp_rwmtx_rwunlock(lck1);
+    erts_rwmtx_rwunlock(lck1);
     if (lck2)
-	erts_smp_rwmtx_rwunlock(lck2);
+	erts_rwmtx_rwunlock(lck2);
     BIF_RET(ret);
  badarg:
     if (tb)
 	db_unlock(tb, LCK_WRITE);
-    erts_smp_rwmtx_rwunlock(lck1);
+    erts_rwmtx_rwunlock(lck1);
     if (lck2)
-	erts_smp_rwmtx_rwunlock(lck2);
+	erts_rwmtx_rwunlock(lck2);
     BIF_ERROR(BIF_P, BADARG);    
 }
 
@@ -1598,9 +1572,7 @@ BIF_RETTYPE ets_new_2(BIF_ALIST_2)
     Uint32 status;
     Sint keypos;
     int is_named, is_compressed;
-#ifdef ERTS_SMP
     int is_fine_locked, frequent_read;
-#endif
 #ifdef DEBUG
     int cret;
 #endif
@@ -1616,10 +1588,8 @@ BIF_RETTYPE ets_new_2(BIF_ALIST_2)
     status = DB_SET | DB_PROTECTED;
     keypos = 1;
     is_named = 0;
-#ifdef ERTS_SMP
     is_fine_locked = 0;
     frequent_read = 0;
-#endif
     heir = am_none;
     heir_data = (UWord) am_undefined;
     is_compressed = erts_ets_always_compress;
@@ -1647,30 +1617,18 @@ BIF_RETTYPE ets_new_2(BIF_ALIST_2)
 		    keypos = signed_val(tp[2]);
 		}		
 		else if (tp[1] == am_write_concurrency) {
-#ifdef ERTS_SMP
 		    if (tp[2] == am_true) {
 			is_fine_locked = 1;
 		    } else if (tp[2] == am_false) {
 			is_fine_locked = 0;
 		    } else break;
-#else
-		    if ((tp[2] != am_true) &&  (tp[2] != am_false)) {
-			break;
-		    }
-#endif
 		}
 		else if (tp[1] == am_read_concurrency) {
-#ifdef ERTS_SMP
 		    if (tp[2] == am_true) {
 			frequent_read = 1;
 		    } else if (tp[2] == am_false) {
 			frequent_read = 0;
 		    } else break;
-#else
-		    if ((tp[2] != am_true) &&  (tp[2] != am_false)) {
-			break;
-		    }
-#endif
 		    
 		}
 		else if (tp[1] == am_heir && tp[2] == am_none) {
@@ -1712,11 +1670,9 @@ BIF_RETTYPE ets_new_2(BIF_ALIST_2)
     }
     if (IS_HASH_TABLE(status)) {
 	meth = &db_hash;
-#ifdef ERTS_SMP
 	if (is_fine_locked && !(status & DB_PRIVATE)) {
 	    status |= DB_FINE_LOCKED;
 	}
-#endif
     }
     else if (IS_TREE_TABLE(status)) {
 	meth = &db_tree;
@@ -1725,10 +1681,8 @@ BIF_RETTYPE ets_new_2(BIF_ALIST_2)
 	BIF_ERROR(BIF_P, BADARG);
     }
 
-#ifdef ERTS_SMP
     if (frequent_read && !(status & DB_PRIVATE))
 	status |= DB_FREQ_READ;
-#endif
 
     /* we create table outside any table lock
      * and take the unusal cost of destroy table if it
@@ -1737,27 +1691,25 @@ BIF_RETTYPE ets_new_2(BIF_ALIST_2)
     {
         DbTable init_tb;
 
-	erts_smp_atomic_init_nob(&init_tb.common.memory_size, 0);
+	erts_atomic_init_nob(&init_tb.common.memory_size, 0);
 	tb = (DbTable*) erts_db_alloc(ERTS_ALC_T_DB_TABLE,
 				      &init_tb, sizeof(DbTable));
-	erts_smp_atomic_init_nob(&tb->common.memory_size,
-				 erts_smp_atomic_read_nob(&init_tb.common.memory_size));
+	erts_atomic_init_nob(&tb->common.memory_size,
+				 erts_atomic_read_nob(&init_tb.common.memory_size));
     }
 
     tb->common.meth = meth;
     tb->common.the_name = BIF_ARG_1;
     tb->common.status = status;    
-#ifdef ERTS_SMP
     tb->common.type = status & ERTS_ETS_TABLE_TYPES;
     /* Note, 'type' is *read only* from now on... */
-#endif
-    erts_smp_refc_init(&tb->common.fix_count, 0);
+    erts_refc_init(&tb->common.fix_count, 0);
     db_init_lock(tb, status & (DB_FINE_LOCKED|DB_FREQ_READ));
     tb->common.keypos = keypos;
     tb->common.owner = BIF_P->common.id;
     set_heir(BIF_P, tb, heir, heir_data);
 
-    erts_smp_atomic_init_nob(&tb->common.nitems, 0);
+    erts_atomic_init_nob(&tb->common.nitems, 0);
 
     tb->common.fixing_procs = NULL;
     tb->common.compress = is_compressed;
@@ -1940,7 +1892,7 @@ BIF_RETTYPE ets_delete_1(BIF_ALIST_1)
          * Process 'rp' might be exiting, but our table lock prevents it
          * from terminating as it cannot complete erts_db_process_exiting().
          */
-        ASSERT(!(ERTS_PSFLG_FREE & erts_smp_atomic32_read_nob(&rp->state)));
+        ASSERT(!(ERTS_PSFLG_FREE & erts_atomic32_read_nob(&rp->state)));
 
         delete_owned_table(rp, tb);
         BIF_P->flags |= F_USING_DB;
@@ -2015,12 +1967,12 @@ BIF_RETTYPE ets_give_away_3(BIF_ALIST_3)
     db_unlock(tb,LCK_WRITE);
     send_ets_transfer_message(BIF_P, to_proc, &to_locks,
                               tb, BIF_ARG_3);
-    erts_smp_proc_unlock(to_proc, to_locks);
+    erts_proc_unlock(to_proc, to_locks);
     UnUseTmpHeap(5,BIF_P);
     BIF_RET(am_true);
 
 badarg:
-    if (to_proc != NULL && to_proc != BIF_P) erts_smp_proc_unlock(to_proc, to_locks);
+    if (to_proc != NULL && to_proc != BIF_P) erts_proc_unlock(to_proc, to_locks);
     if (tb != NULL) db_unlock(tb, LCK_WRITE);
     BIF_ERROR(BIF_P, BADARG);
 }
@@ -2244,7 +2196,7 @@ BIF_RETTYPE ets_select_delete_2(BIF_ALIST_2)
 	if ((tb = db_get_table(BIF_P, BIF_ARG_1, DB_WRITE, LCK_WRITE)) == NULL) {
 	    BIF_ERROR(BIF_P, BADARG);
 	}
-	nitems = erts_smp_atomic_read_nob(&tb->common.nitems);
+	nitems = erts_atomic_read_nob(&tb->common.nitems);
 	tb->common.meth->db_delete_all_objects(BIF_P, tb);
 	db_unlock(tb, LCK_WRITE);
 	BIF_RET(erts_make_integer(nitems,BIF_P));
@@ -2295,7 +2247,7 @@ BIF_RETTYPE ets_select_delete_2(BIF_ALIST_2)
  */
 
 struct ErtsEtsAllReq_ {
-    erts_smp_atomic32_t refc;
+    erts_atomic32_t refc;
     Process *proc;
     ErtsOIRefStorage ref;
     ErtsEtsAllReqList list[1]; /* one per scheduler */
@@ -2428,7 +2380,7 @@ ets_all_reply(ErtsSchedulerData *esdp, ErtsEtsAllReq **reqpp,
 
     erts_proc_dec_refc(reqp->proc);
 
-    if (erts_smp_atomic32_dec_read_nob(&reqp->refc) == 0)
+    if (erts_atomic32_dec_read_nob(&reqp->refc) == 0)
         erts_free(ERTS_ALC_T_ETS_ALL_REQ, reqp);
 
     *reqpp = NULL;
@@ -2516,19 +2468,17 @@ BIF_RETTYPE ets_internal_request_all_0(BIF_ALIST_0)
     Eterm ref = erts_make_ref(BIF_P);
     ErtsEtsAllReq *req = erts_alloc(ERTS_ALC_T_ETS_ALL_REQ,
                                     ERTS_ETS_ALL_REQ_SIZE);
-    erts_smp_atomic32_init_nob(&req->refc,
+    erts_atomic32_init_nob(&req->refc,
 			       (erts_aint32_t) erts_no_schedulers);
     erts_oiref_storage_save(&req->ref, ref);
     req->proc = BIF_P;
     erts_proc_add_refc(BIF_P, (Sint) erts_no_schedulers);
 
-#ifdef ERTS_SMP
     if (erts_no_schedulers > 1)
 	erts_schedule_multi_misc_aux_work(1,
 					  erts_no_schedulers,
                                           handle_ets_all_request,
 					  (void *) req);
-#endif
 
     handle_ets_all_request((void *) req);
     BIF_RET(ref);
@@ -3212,7 +3162,7 @@ BIF_RETTYPE ets_info_1(BIF_ALIST_1)
 	if ((tb = db_get_table(BIF_P, BIF_ARG_1, DB_INFO, LCK_READ)) == NULL
 	    || tb->common.owner != owner) {
 	    if (BIF_P != rp)
-		erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_MAIN);
+		erts_proc_unlock(rp, ERTS_PROC_LOCK_MAIN);
 	    if (is_atom(BIF_ARG_1) || is_small(BIF_ARG_1)) {
 		BIF_RET(am_undefined);
 	    }
@@ -3226,7 +3176,7 @@ BIF_RETTYPE ets_info_1(BIF_ALIST_1)
     db_unlock(tb, LCK_READ);
 
     /*if (rp != NULL && rp != BIF_P)
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_MAIN);*/
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_MAIN);*/
 
     hp = HAlloc(BIF_P, 5*sizeof(fields)/sizeof(Eterm));
     res = NIL;
@@ -3345,11 +3295,10 @@ void init_db(ErtsDbSpinCount db_spin_count)
     unsigned bits;
     size_t size;
 
-#ifdef ERTS_SMP
     int max_spin_count = (1 << 15) - 1; /* internal limit */
-    erts_smp_rwmtx_opt_t rwmtx_opt = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
-    rwmtx_opt.type = ERTS_SMP_RWMTX_TYPE_FREQUENT_READ;
-    rwmtx_opt.lived = ERTS_SMP_RWMTX_LONG_LIVED;
+    erts_rwmtx_opt_t rwmtx_opt = ERTS_RWMTX_OPT_DEFAULT_INITER;
+    rwmtx_opt.type = ERTS_RWMTX_TYPE_FREQUENT_READ;
+    rwmtx_opt.lived = ERTS_RWMTX_LONG_LIVED;
 
     switch (db_spin_count) {
     case ERTS_DB_SPNCNT_NONE:
@@ -3389,13 +3338,12 @@ void init_db(ErtsDbSpinCount db_spin_count)
 	rwmtx_opt.main_spincount = erts_ets_rwmtx_spin_count;
 
     for (i=0; i<META_NAME_TAB_LOCK_CNT; i++) {
-        erts_smp_rwmtx_init_opt(&meta_name_tab_rwlocks[i].lck, &rwmtx_opt,
+        erts_rwmtx_init_opt(&meta_name_tab_rwlocks[i].lck, &rwmtx_opt,
             "meta_name_tab", make_small(i),
             ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_DB);
     }
-#endif
 
-    erts_smp_atomic_init_nob(&erts_ets_misc_mem_size, 0);
+    erts_atomic_init_nob(&erts_ets_misc_mem_size, 0);
     db_initialize_util();
 
     if (user_requested_db_max_tabs < DB_DEF_MAX_TABS)
@@ -3496,14 +3444,14 @@ retry:
     
 	if (tb->common.owner != p->common.id) {
 	    if (to_proc != NULL ) {
-		erts_smp_proc_unlock(to_proc, to_locks);
+		erts_proc_unlock(to_proc, to_locks);
 	    }
 	    db_unlock(tb,LCK_WRITE);
 	    return !0; /* ok, someone already gave my table away */
 	}
 	if (tb->common.heir != to_pid) {  /* someone changed the heir */ 
 	    if (to_proc != NULL ) {
-		erts_smp_proc_unlock(to_proc, to_locks);
+		erts_proc_unlock(to_proc, to_locks);
 	    }
 	    if (to_pid == p->common.id || to_pid == am_none) {
 		return 0; /* no real heir, table still mine */
@@ -3516,7 +3464,7 @@ retry:
     }
     if (to_proc->common.u.alive.started_interval
 	!= tb->common.heir_started_interval) {
-	erts_smp_proc_unlock(to_proc, to_locks);
+	erts_proc_unlock(to_proc, to_locks);
 	return 0; /* heir dead and pid reused, table still mine */
     }
     
@@ -3533,7 +3481,7 @@ retry:
 	heir_data = tpv[1];
     }
     send_ets_transfer_message(p, to_proc, &to_locks, tb, heir_data);
-    erts_smp_proc_unlock(to_proc, to_locks);
+    erts_proc_unlock(to_proc, to_locks);
     return !0;
 }
 
@@ -3584,21 +3532,17 @@ static SWord proc_cleanup_fixed_table(Process* p, DbFixation* fix)
 	db_lock(tb, LCK_WRITE_REC);
 	if (!(tb->common.status & DB_DELETE)) {
 	    erts_aint_t diff;
-    #ifdef ERTS_SMP
-	    erts_smp_mtx_lock(&tb->common.fixlock);
-    #endif
+	    erts_mtx_lock(&tb->common.fixlock);
 
 	    ASSERT(fixing_procs_rbt_lookup(tb->common.fixing_procs, p));
 
 	    diff = -((erts_aint_t) fix->counter);
-	    erts_smp_refc_add(&tb->common.fix_count,diff,0);
+	    erts_refc_add(&tb->common.fix_count,diff,0);
 	    fix->counter = 0;
 
 	    fixing_procs_rbt_delete(&tb->common.fixing_procs, fix);
 
-    #ifdef ERTS_SMP
-	    erts_smp_mtx_unlock(&tb->common.fixlock);
-    #endif
+	    erts_mtx_unlock(&tb->common.fixlock);
 	    if (!IS_FIXED(tb) && IS_HASH_TABLE(tb->common.status)) {
 		work += db_unfix_table_hash(&(tb->hash));
 	    }
@@ -3655,9 +3599,9 @@ erts_db_process_exiting(Process *c_p, ErtsProcLocks c_p_locks)
 	switch (state->op) {
         case GET_OWNED_TABLE: {
             DbTable* tb;
-            erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_STATUS);
+            erts_proc_lock(c_p, ERTS_PROC_LOCK_STATUS);
             tb = (DbTable*) erts_psd_get(c_p, ERTS_PSD_ETS_OWNED_TABLES);
-            erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_STATUS);
+            erts_proc_unlock(c_p, ERTS_PROC_LOCK_STATUS);
 
             if (!tb) {
                 /* Done with owned tables; now fixations */
@@ -3748,10 +3692,8 @@ static void fix_table_locked(Process* p, DbTable* tb)
 {
     DbFixation *fix;
 
-#ifdef ERTS_SMP
-    erts_smp_mtx_lock(&tb->common.fixlock);
-#endif
-    erts_smp_refc_inc(&tb->common.fix_count,1);
+    erts_mtx_lock(&tb->common.fixlock);
+    erts_refc_inc(&tb->common.fix_count,1);
     fix = tb->common.fixing_procs;
     if (fix == NULL) {
 	tb->common.time.monotonic
@@ -3764,9 +3706,7 @@ static void fix_table_locked(Process* p, DbTable* tb)
 	    ASSERT(fixed_tabs_find(NULL, fix));
 	    ++(fix->counter);
 
-#ifdef ERTS_SMP
-	    erts_smp_mtx_unlock(&tb->common.fixlock);
-#endif
+	    erts_mtx_unlock(&tb->common.fixlock);
 	    return;
 	}
     }
@@ -3779,9 +3719,7 @@ static void fix_table_locked(Process* p, DbTable* tb)
     fix->counter = 1;
     fixing_procs_rbt_insert(&tb->common.fixing_procs, fix);
 
-#ifdef ERTS_SMP
-    erts_smp_mtx_unlock(&tb->common.fixlock);
-#endif
+    erts_mtx_unlock(&tb->common.fixlock);
     p->flags |= F_USING_DB;
 
     fixed_tabs_insert(p, fix);
@@ -3794,20 +3732,16 @@ static void unfix_table_locked(Process* p,  DbTable* tb,
 {
     DbFixation* fix;
 
-#ifdef ERTS_SMP
-    erts_smp_mtx_lock(&tb->common.fixlock);
-#endif
+    erts_mtx_lock(&tb->common.fixlock);
     fix = fixing_procs_rbt_lookup(tb->common.fixing_procs, p);
 
     if (fix) {
-	erts_smp_refc_dec(&tb->common.fix_count,0);
+	erts_refc_dec(&tb->common.fix_count,0);
 	--(fix->counter);
 	ASSERT(fix->counter >= 0);
 	if (fix->counter == 0) {
 	    fixing_procs_rbt_delete(&tb->common.fixing_procs, fix);
-#ifdef ERTS_SMP
-	    erts_smp_mtx_unlock(&tb->common.fixlock);
-#endif
+	    erts_mtx_unlock(&tb->common.fixlock);
 	    fixed_tabs_delete(p, fix);
 
 	    erts_refc_dec(&fix->tabs.btid->intern.refc, 1);
@@ -3818,22 +3752,18 @@ static void unfix_table_locked(Process* p,  DbTable* tb,
 	    goto unlocked;
 	}
     }
-#ifdef ERTS_SMP
-    erts_smp_mtx_unlock(&tb->common.fixlock);
-#endif
+    erts_mtx_unlock(&tb->common.fixlock);
 unlocked:
 
     if (!IS_FIXED(tb) && IS_HASH_TABLE(tb->common.status)
-	&& erts_smp_atomic_read_nob(&tb->hash.fixdel) != (erts_aint_t)NULL) {
-#ifdef ERTS_SMP
+	&& erts_atomic_read_nob(&tb->hash.fixdel) != (erts_aint_t)NULL) {
 	if (*kind_p == LCK_READ && tb->common.is_thread_safe) {
 	    /* Must have write lock while purging pseudo-deleted (OTP-8166) */
-	    erts_smp_rwmtx_runlock(&tb->common.rwlock);
-	    erts_smp_rwmtx_rwlock(&tb->common.rwlock);
+	    erts_rwmtx_runlock(&tb->common.rwlock);
+	    erts_rwmtx_rwlock(&tb->common.rwlock);
 	    *kind_p = LCK_WRITE;
 	    if (tb->common.status & DB_DELETE) return;
 	}
-#endif
 	db_unfix_table_hash(&(tb->hash));
     }
 }
@@ -3855,9 +3785,8 @@ static void free_fixations_op(DbFixation* fix, void* vctx)
     ASSERT(ctx->tb->common.status & DB_DELETE);
 
     diff = -((erts_aint_t) fix->counter);
-    erts_smp_refc_add(&ctx->tb->common.fix_count, diff, 0);
+    erts_refc_add(&ctx->tb->common.fix_count, diff, 0);
 
-#ifdef ERTS_SMP
     if (fix->procs.p != ctx->p) { /* Fixated by other process */
         fix->counter = 0;
 
@@ -3873,7 +3802,6 @@ static void free_fixations_op(DbFixation* fix, void* vctx)
          */
     }
     else
-#endif
     {
         fixed_tabs_delete(fix->procs.p, fix);
 
@@ -3886,7 +3814,6 @@ static void free_fixations_op(DbFixation* fix, void* vctx)
     ctx->cnt++;
 }
 
-#ifdef ERTS_SMP
 int erts_db_execute_free_fixation(Process* p, DbFixation* fix)
 {
     ASSERT(fix->counter == 0);
@@ -3898,13 +3825,12 @@ int erts_db_execute_free_fixation(Process* p, DbFixation* fix)
     ERTS_ETS_MISC_MEM_ADD(-sizeof(DbFixation));
     return 1;
 }
-#endif
 
 static SWord free_fixations_locked(Process* p, DbTable *tb)
 {
     struct free_fixations_ctx ctx;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_rwmtx_is_rwlocked(&tb->common.rwlock));
+    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(&tb->common.rwlock));
 
     ctx.p = p;
     ctx.tb = tb;
@@ -4047,7 +3973,7 @@ static Eterm table_info(Process* p, DbTable* tb, Eterm What)
     int use_monotonic;
 
     if (What == am_size) {
-	ret = make_small(erts_smp_atomic_read_nob(&tb->common.nitems));
+	ret = make_small(erts_atomic_read_nob(&tb->common.nitems));
     } else if (What == am_type) {
 	if (tb->common.status & DB_SET)  {
 	    ret = am_set;
@@ -4060,7 +3986,7 @@ static Eterm table_info(Process* p, DbTable* tb, Eterm What)
 	    ret = am_bag;
 	}
     } else if (What == am_memory) {
-	Uint words = (Uint) ((erts_smp_atomic_read_nob(&tb->common.memory_size)
+	Uint words = (Uint) ((erts_atomic_read_nob(&tb->common.memory_size)
 			      + sizeof(Uint)
 			      - 1)
 			     / sizeof(Uint));
@@ -4106,9 +4032,7 @@ static Eterm table_info(Process* p, DbTable* tb, Eterm What)
 		= ERTS_IS_ATOM_STR("safe_fixed_monotonic_time",
 				   What))
 	       || ERTS_IS_ATOM_STR("safe_fixed", What)) {
-#ifdef ERTS_SMP
-	erts_smp_mtx_lock(&tb->common.fixlock);
-#endif
+	erts_mtx_lock(&tb->common.fixlock);
 	if (IS_FIXED(tb)) {
 	    Uint need;
 	    Eterm *hp;
@@ -4150,9 +4074,7 @@ static Eterm table_info(Process* p, DbTable* tb, Eterm What)
 	} else {
 	    ret = am_false;
 	}
-#ifdef ERTS_SMP
-	erts_smp_mtx_unlock(&tb->common.fixlock);
-#endif
+	erts_mtx_unlock(&tb->common.fixlock);
     } else if (What == am_atom_put("stats",5)) {
 	if (IS_HASH_TABLE(tb->common.status)) {
 	    FloatDef f;
@@ -4176,7 +4098,7 @@ static Eterm table_info(Process* p, DbTable* tb, Eterm What)
 	    std_dev_exp = make_float(hp);
 	    PUT_DOUBLE(f, hp);
 	    hp += FLOAT_SIZE_OBJECT;
-	    ret = TUPLE7(hp, make_small(erts_smp_atomic_read_nob(&tb->hash.nactive)),
+	    ret = TUPLE7(hp, make_small(erts_atomic_read_nob(&tb->hash.nactive)),
 			 avg, std_dev_real, std_dev_exp,
 			 make_small(stats.min_chain_len),
 			 make_small(stats.max_chain_len),
@@ -4208,9 +4130,9 @@ static void print_table(fmtfn_t to, void *to_arg, int show,  DbTable* tb)
 
     tb->common.meth->db_print(to, to_arg, show, tb);
 
-    erts_print(to, to_arg, "Objects: %d\n", (int)erts_smp_atomic_read_nob(&tb->common.nitems));
+    erts_print(to, to_arg, "Objects: %d\n", (int)erts_atomic_read_nob(&tb->common.nitems));
     erts_print(to, to_arg, "Words: %bpu\n",
-	       (Uint) ((erts_smp_atomic_read_nob(&tb->common.memory_size)
+	       (Uint) ((erts_atomic_read_nob(&tb->common.memory_size)
 			+ sizeof(Uint)
 			- 1)
 		       / sizeof(Uint)));
@@ -4250,9 +4172,9 @@ void db_info(fmtfn_t to, void *to_arg, int show)    /* Called by break handler *
 Uint
 erts_get_ets_misc_mem_size(void)
 {
-    ERTS_SMP_MEMORY_BARRIER;
+    ERTS_THR_MEMORY_BARRIER;
     /* Memory not allocated in ets_alloc */
-    return (Uint) erts_smp_atomic_read_nob(&erts_ets_misc_mem_size);
+    return (Uint) erts_atomic_read_nob(&erts_ets_misc_mem_size);
 }
 
 /* SMP Note: May only be used when system is locked */
@@ -4261,7 +4183,7 @@ erts_db_foreach_table(void (*func)(DbTable *, void *), void *arg)
 {
     int ix;
 
-    ASSERT(erts_smp_thr_progress_is_blocking());
+    ASSERT(erts_thr_progress_is_blocking());
 
     for (ix = 0; ix < erts_no_schedulers; ix++) {
         ErtsSchedulerData *esdp = ERTS_SCHEDULER_IX(ix);
@@ -4367,4 +4289,4 @@ void erts_lcnt_update_db_locks(int enable) {
         &lcnt_update_db_locks_per_sched, (void*)(UWord)enable);
 }
 
-#endif /* ERTS_ENABLE_LOCK_COUNT */
\ No newline at end of file
+#endif /* ERTS_ENABLE_LOCK_COUNT */
diff --git a/erts/emulator/beam/erl_db.h b/erts/emulator/beam/erl_db.h
index d83126b3a2..318e90cb28 100644
--- a/erts/emulator/beam/erl_db.h
+++ b/erts/emulator/beam/erl_db.h
@@ -124,7 +124,7 @@ extern Export ets_select_delete_continue_exp;
 extern Export ets_select_count_continue_exp;
 extern Export ets_select_replace_continue_exp;
 extern Export ets_select_continue_exp;
-extern erts_smp_atomic_t erts_ets_misc_mem_size;
+extern erts_atomic_t erts_ets_misc_mem_size;
 
 Eterm erts_ets_colliding_names(Process*, Eterm name, Uint cnt);
 Uint erts_db_get_max_tabs(void);
@@ -151,11 +151,11 @@ do {									\
     erts_aint_t sz__ = (((erts_aint_t) (ALLOC_SZ))			\
 			- ((erts_aint_t) (FREE_SZ)));			\
     ASSERT((TAB));							\
-    erts_smp_atomic_add_nob(&(TAB)->common.memory_size, sz__);		\
+    erts_atomic_add_nob(&(TAB)->common.memory_size, sz__);		\
 } while (0)
 
 #define ERTS_ETS_MISC_MEM_ADD(SZ) \
-  erts_smp_atomic_add_nob(&erts_ets_misc_mem_size, (SZ));
+  erts_atomic_add_nob(&erts_ets_misc_mem_size, (SZ));
 
 ERTS_GLB_INLINE void *erts_db_alloc(ErtsAlcType_t type,
 				    DbTable *tab,
@@ -292,7 +292,7 @@ erts_db_free(ErtsAlcType_t type, DbTable *tab, void *ptr, Uint size)
     ERTS_DB_ALC_MEM_UPDATE_(tab, size, 0);
 
     ASSERT(((void *) tab) != ptr
-	   || erts_smp_atomic_read_nob(&tab->common.memory_size) == 0);
+	   || erts_atomic_read_nob(&tab->common.memory_size) == 0);
 
     erts_free(type, ptr);
 }
diff --git a/erts/emulator/beam/erl_db_hash.c b/erts/emulator/beam/erl_db_hash.c
index cf928a9035..5d49b2ea14 100644
--- a/erts/emulator/beam/erl_db_hash.c
+++ b/erts/emulator/beam/erl_db_hash.c
@@ -109,22 +109,18 @@
 #define NSEG_2   256 /* Size of second segment table */
 #define NSEG_INC 128 /* Number of segments to grow after that */
 
-#ifdef ERTS_SMP
 #  define DB_USING_FINE_LOCKING(TB) (((TB))->common.type & DB_FINE_LOCKED)
-#else
-#  define DB_USING_FINE_LOCKING(TB) 0
-#endif
 
 #ifdef ETHR_ORDERED_READ_DEPEND
-#define SEGTAB(tb) ((struct segment**) erts_smp_atomic_read_nob(&(tb)->segtab))
+#define SEGTAB(tb) ((struct segment**) erts_atomic_read_nob(&(tb)->segtab))
 #else
 #define SEGTAB(tb)							\
     (DB_USING_FINE_LOCKING(tb)						\
-     ? ((struct segment**) erts_smp_atomic_read_ddrb(&(tb)->segtab))	\
-     : ((struct segment**) erts_smp_atomic_read_nob(&(tb)->segtab)))
+     ? ((struct segment**) erts_atomic_read_ddrb(&(tb)->segtab))	\
+     : ((struct segment**) erts_atomic_read_nob(&(tb)->segtab)))
 #endif
-#define NACTIVE(tb) ((int)erts_smp_atomic_read_nob(&(tb)->nactive))
-#define NITEMS(tb) ((int)erts_smp_atomic_read_nob(&(tb)->common.nitems))
+#define NACTIVE(tb) ((int)erts_atomic_read_nob(&(tb)->nactive))
+#define NITEMS(tb) ((int)erts_atomic_read_nob(&(tb)->common.nitems))
 
 #define SLOT_IX_TO_SEG_IX(i) (((i)+(EXT_SEGSZ-FIRST_SEGSZ)) >> EXT_SEGSZ_EXP)
 
@@ -142,12 +138,12 @@
 static ERTS_INLINE Uint hash_to_ix(DbTableHash* tb, HashValue hval)
 {
     Uint mask = (DB_USING_FINE_LOCKING(tb)
-		 ? erts_smp_atomic_read_acqb(&tb->szm)
-		 : erts_smp_atomic_read_nob(&tb->szm));
+		 ? erts_atomic_read_acqb(&tb->szm)
+		 : erts_atomic_read_nob(&tb->szm));
     Uint ix = hval & mask; 
-    if (ix >= erts_smp_atomic_read_nob(&tb->nactive)) {
+    if (ix >= erts_atomic_read_nob(&tb->nactive)) {
 	ix &= mask>>1;
-	ASSERT(ix < erts_smp_atomic_read_nob(&tb->nactive));
+	ASSERT(ix < erts_atomic_read_nob(&tb->nactive));
     }
     return ix;
 }
@@ -166,7 +162,7 @@ static ERTS_INLINE int add_fixed_deletion(DbTableHash* tb, int ix,
 							 sizeof(FixedDeletion));
     ERTS_ETS_MISC_MEM_ADD(sizeof(FixedDeletion));
     fixd->slot = ix;
-    was_next = erts_smp_atomic_read_acqb(&tb->fixdel);
+    was_next = erts_atomic_read_acqb(&tb->fixdel);
     do { /* Lockless atomic insertion in linked list: */
         if (NFIXED(tb) <= fixated_by_me) {
             erts_db_free(ERTS_ALC_T_DB_FIX_DEL, (DbTable*)tb,
@@ -175,7 +171,7 @@ static ERTS_INLINE int add_fixed_deletion(DbTableHash* tb, int ix,
         }
         exp_next = was_next;
 	fixd->next = (FixedDeletion*) exp_next;
-	was_next = erts_smp_atomic_cmpxchg_mb(&tb->fixdel,
+	was_next = erts_atomic_cmpxchg_mb(&tb->fixdel,
                                               (erts_aint_t) fixd,
                                               exp_next);
     }while (was_next != exp_next);
@@ -191,62 +187,55 @@ static ERTS_INLINE int add_fixed_deletion(DbTableHash* tb, int ix,
     ((is_atom(term) ? (atom_tab(atom_val(term))->slot.bucket.hvalue) : \
       make_internal_hash(term, 0)) % MAX_HASH)
 
-#ifdef ERTS_SMP
 #  define DB_HASH_LOCK_MASK (DB_HASH_LOCK_CNT-1)
 #  define GET_LOCK(tb,hval) (&(tb)->locks->lck_vec[(hval) & DB_HASH_LOCK_MASK].lck)
 #  define GET_LOCK_MAYBE(tb,hval) ((tb)->common.is_thread_safe ? NULL : GET_LOCK(tb,hval))
 
 /* Fine grained read lock */
-static ERTS_INLINE erts_smp_rwmtx_t* RLOCK_HASH(DbTableHash* tb, HashValue hval)
+static ERTS_INLINE erts_rwmtx_t* RLOCK_HASH(DbTableHash* tb, HashValue hval)
 {
     if (tb->common.is_thread_safe) {
 	return NULL;
     } else {
-	erts_smp_rwmtx_t* lck = GET_LOCK(tb,hval);
+	erts_rwmtx_t* lck = GET_LOCK(tb,hval);
 	ASSERT(tb->common.type & DB_FINE_LOCKED);
-	erts_smp_rwmtx_rlock(lck);
+	erts_rwmtx_rlock(lck);
 	return lck;
     }
 }
 /* Fine grained write lock */
-static ERTS_INLINE erts_smp_rwmtx_t* WLOCK_HASH(DbTableHash* tb, HashValue hval)
+static ERTS_INLINE erts_rwmtx_t* WLOCK_HASH(DbTableHash* tb, HashValue hval)
 {
     if (tb->common.is_thread_safe) {
 	return NULL;
     } else {
-	erts_smp_rwmtx_t* lck = GET_LOCK(tb,hval);
+	erts_rwmtx_t* lck = GET_LOCK(tb,hval);
 	ASSERT(tb->common.type & DB_FINE_LOCKED);
-	erts_smp_rwmtx_rwlock(lck);
+	erts_rwmtx_rwlock(lck);
 	return lck;
     }
 }
 
-static ERTS_INLINE void RUNLOCK_HASH(erts_smp_rwmtx_t* lck)
+static ERTS_INLINE void RUNLOCK_HASH(erts_rwmtx_t* lck)
 {
     if (lck != NULL) {
-	erts_smp_rwmtx_runlock(lck);
+	erts_rwmtx_runlock(lck);
     }
 }
 
-static ERTS_INLINE void WUNLOCK_HASH(erts_smp_rwmtx_t* lck)
+static ERTS_INLINE void WUNLOCK_HASH(erts_rwmtx_t* lck)
 {
     if (lck != NULL) {
-	erts_smp_rwmtx_rwunlock(lck);
+	erts_rwmtx_rwunlock(lck);
     }
 }
-#else /* ERTS_SMP */
-# define RLOCK_HASH(tb,hval) NULL 
-# define WLOCK_HASH(tb,hval) NULL
-# define RUNLOCK_HASH(lck) ((void)lck) 
-# define WUNLOCK_HASH(lck) ((void)lck)
-#endif /* ERTS_SMP */
 
 
 #ifdef ERTS_ENABLE_LOCK_CHECK
 #  define IFN_EXCL(tb,cmd) (((tb)->common.is_thread_safe) || (cmd))
-#  define IS_HASH_RLOCKED(tb,hval) IFN_EXCL(tb,erts_smp_lc_rwmtx_is_rlocked(GET_LOCK(tb,hval)))
-#  define IS_HASH_WLOCKED(tb,lck) IFN_EXCL(tb,erts_smp_lc_rwmtx_is_rwlocked(lck))
-#  define IS_TAB_WLOCKED(tb) erts_smp_lc_rwmtx_is_rwlocked(&(tb)->common.rwlock)
+#  define IS_HASH_RLOCKED(tb,hval) IFN_EXCL(tb,erts_lc_rwmtx_is_rlocked(GET_LOCK(tb,hval)))
+#  define IS_HASH_WLOCKED(tb,lck) IFN_EXCL(tb,erts_lc_rwmtx_is_rwlocked(lck))
+#  define IS_TAB_WLOCKED(tb) erts_lc_rwmtx_is_rwlocked(&(tb)->common.rwlock)
 #else
 #  define IS_HASH_RLOCKED(tb,hval) (1)
 #  define IS_HASH_WLOCKED(tb,hval) (1)
@@ -259,33 +248,25 @@ static ERTS_INLINE void WUNLOCK_HASH(erts_smp_rwmtx_t* lck)
 ** Slot READ locks updated accordingly, unlocked if EOT.
 */
 static ERTS_INLINE Sint next_slot(DbTableHash* tb, Uint ix,
-				  erts_smp_rwmtx_t** lck_ptr)
+				  erts_rwmtx_t** lck_ptr)
 {
-#ifdef ERTS_SMP
     ix += DB_HASH_LOCK_CNT;
     if (ix < NACTIVE(tb)) return ix;
     RUNLOCK_HASH(*lck_ptr);
     ix = (ix + 1) & DB_HASH_LOCK_MASK;
     if (ix != 0) *lck_ptr = RLOCK_HASH(tb,ix);
     return ix;
-#else
-    return (++ix < NACTIVE(tb)) ? ix : 0;
-#endif
 }
 /* Same as next_slot but with WRITE locking */
 static ERTS_INLINE Sint next_slot_w(DbTableHash* tb, Uint ix,
-				    erts_smp_rwmtx_t** lck_ptr)
+				    erts_rwmtx_t** lck_ptr)
 {
-#ifdef ERTS_SMP
     ix += DB_HASH_LOCK_CNT;
     if (ix < NACTIVE(tb)) return ix;
     WUNLOCK_HASH(*lck_ptr);
     ix = (ix + 1) & DB_HASH_LOCK_MASK;
     if (ix != 0) *lck_ptr = WLOCK_HASH(tb,ix);
     return ix;
-#else
-    return next_slot(tb,ix,lck_ptr);
-#endif
 }
 
 
@@ -331,9 +312,7 @@ struct segment {
 
 /* An extended segment table */
 struct ext_segtab {
-#ifdef ERTS_SMP
     ErtsThrPrgrLaterOp lop;
-#endif
     struct segment** prev_segtab;  /* Used when table is shrinking */
     int prev_nsegs;                /* Size of prev_segtab */
     int nsegs;                     /* Size of this segtab */
@@ -347,9 +326,9 @@ static ERTS_INLINE void SET_SEGTAB(DbTableHash* tb,
 				   struct segment** segtab)
 {
     if (DB_USING_FINE_LOCKING(tb))
-	erts_smp_atomic_set_wb(&tb->segtab, (erts_aint_t) segtab);
+	erts_atomic_set_wb(&tb->segtab, (erts_aint_t) segtab);
     else
-	erts_smp_atomic_set_nob(&tb->segtab, (erts_aint_t) segtab);
+	erts_atomic_set_nob(&tb->segtab, (erts_aint_t) segtab);
 }
 
 /* Used by select_replace on analyze_pattern */
@@ -361,7 +340,7 @@ typedef int (*extra_match_validator_t)(int keypos, Eterm match, Eterm guard, Ete
 static struct ext_segtab* alloc_ext_segtab(DbTableHash* tb, unsigned seg_ix);
 static void alloc_seg(DbTableHash *tb);
 static int free_seg(DbTableHash *tb, int free_records);
-static HashDbTerm* next(DbTableHash *tb, Uint *iptr, erts_smp_rwmtx_t** lck_ptr,
+static HashDbTerm* next(DbTableHash *tb, Uint *iptr, erts_rwmtx_t** lck_ptr,
 			HashDbTerm *list);
 static HashDbTerm* search_list(DbTableHash* tb, Eterm key, 
 			       HashValue hval, HashDbTerm *list);
@@ -559,7 +538,7 @@ static void restore_fixdel(DbTableHash* tb, FixedDeletion* fixdel)
 {
     /*int tries = 0;*/
     DEBUG_WAIT();
-    if (erts_smp_atomic_cmpxchg_relb(&tb->fixdel,
+    if (erts_atomic_cmpxchg_relb(&tb->fixdel,
 				     (erts_aint_t) fixdel,
 				     (erts_aint_t) NULL) != (erts_aint_t) NULL) {
 	/* Oboy, must join lists */    
@@ -568,13 +547,13 @@ static void restore_fixdel(DbTableHash* tb, FixedDeletion* fixdel)
 	erts_aint_t exp_tail;
 
 	while (last->next != NULL) last = last->next;
-	was_tail = erts_smp_atomic_read_acqb(&tb->fixdel);
+	was_tail = erts_atomic_read_acqb(&tb->fixdel);
 	do { /* Lockless atomic list insertion */
 	    exp_tail = was_tail;
 	    last->next = (FixedDeletion*) exp_tail;
 	    /*++tries;*/
 	    DEBUG_WAIT();
-	    was_tail = erts_smp_atomic_cmpxchg_relb(&tb->fixdel,
+	    was_tail = erts_atomic_cmpxchg_relb(&tb->fixdel,
 						    (erts_aint_t) fixdel,
 						    exp_tail);
 	}while (was_tail != exp_tail);
@@ -590,18 +569,18 @@ SWord db_unfix_table_hash(DbTableHash *tb)
     FixedDeletion* fixdel;
     SWord work = 0;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_rwmtx_is_rwlocked(&tb->common.rwlock)
-		       || (erts_smp_lc_rwmtx_is_rlocked(&tb->common.rwlock)
+    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(&tb->common.rwlock)
+		       || (erts_lc_rwmtx_is_rlocked(&tb->common.rwlock)
 			   && !tb->common.is_thread_safe));
 restart:
-    fixdel = (FixedDeletion*) erts_smp_atomic_xchg_mb(&tb->fixdel,
+    fixdel = (FixedDeletion*) erts_atomic_xchg_mb(&tb->fixdel,
                                                       (erts_aint_t) NULL);
     while (fixdel != NULL) {
 	FixedDeletion *fx = fixdel;
 	int ix = fx->slot;
 	HashDbTerm **bp;
 	HashDbTerm *b;
-	erts_smp_rwmtx_t* lck = WLOCK_HASH(tb,ix);
+	erts_rwmtx_t* lck = WLOCK_HASH(tb,ix);
 
 	if (IS_FIXED(tb)) { /* interrupted by fixer */
 	    WUNLOCK_HASH(lck);
@@ -647,10 +626,10 @@ int db_create_hash(Process *p, DbTable *tbl)
 {
     DbTableHash *tb = &tbl->hash;
 
-    erts_smp_atomic_init_nob(&tb->szm, FIRST_SEGSZ_MASK);
-    erts_smp_atomic_init_nob(&tb->nactive, FIRST_SEGSZ);
-    erts_smp_atomic_init_nob(&tb->fixdel, (erts_aint_t)NULL);
-    erts_smp_atomic_init_nob(&tb->segtab, (erts_aint_t)NULL);
+    erts_atomic_init_nob(&tb->szm, FIRST_SEGSZ_MASK);
+    erts_atomic_init_nob(&tb->nactive, FIRST_SEGSZ);
+    erts_atomic_init_nob(&tb->fixdel, (erts_aint_t)NULL);
+    erts_atomic_init_nob(&tb->segtab, (erts_aint_t)NULL);
     SET_SEGTAB(tb, tb->first_segtab);
     tb->nsegs = NSEG_1;
     tb->nslots = FIRST_SEGSZ;
@@ -659,32 +638,30 @@ int db_create_hash(Process *p, DbTable *tbl)
                                                           SIZEOF_SEGMENT(FIRST_SEGSZ));
     sys_memset(tb->first_segtab[0], 0, SIZEOF_SEGMENT(FIRST_SEGSZ));
 
-#ifdef ERTS_SMP
-    erts_smp_atomic_init_nob(&tb->is_resizing, 0);
+    erts_atomic_init_nob(&tb->is_resizing, 0);
     if (tb->common.type & DB_FINE_LOCKED) {
-	erts_smp_rwmtx_opt_t rwmtx_opt = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
+	erts_rwmtx_opt_t rwmtx_opt = ERTS_RWMTX_OPT_DEFAULT_INITER;
 	int i;
 	if (tb->common.type & DB_FREQ_READ)
-	    rwmtx_opt.type = ERTS_SMP_RWMTX_TYPE_FREQUENT_READ;
+	    rwmtx_opt.type = ERTS_RWMTX_TYPE_FREQUENT_READ;
 	if (erts_ets_rwmtx_spin_count >= 0)
 	    rwmtx_opt.main_spincount = erts_ets_rwmtx_spin_count;
 	tb->locks = (DbTableHashFineLocks*) erts_db_alloc_fnf(ERTS_ALC_T_DB_SEG, /* Other type maybe? */ 
 							      (DbTable *) tb,
 							      sizeof(DbTableHashFineLocks));	    	    
 	for (i=0; i<DB_HASH_LOCK_CNT; ++i) {
-            erts_smp_rwmtx_init_opt(&tb->locks->lck_vec[i].lck, &rwmtx_opt,
+            erts_rwmtx_init_opt(&tb->locks->lck_vec[i].lck, &rwmtx_opt,
                 "db_hash_slot", tb->common.the_name, ERTS_LOCK_FLAGS_CATEGORY_DB);
 	}
 	/* This important property is needed to guarantee the two buckets
     	 * involved in a grow/shrink operation it protected by the same lock:
 	 */
-	ASSERT(erts_smp_atomic_read_nob(&tb->nactive) % DB_HASH_LOCK_CNT == 0);
+	ASSERT(erts_atomic_read_nob(&tb->nactive) % DB_HASH_LOCK_CNT == 0);
     }
     else { /* coarse locking */
 	tb->locks = NULL;
     }
     ERTS_THR_MEMORY_BARRIER;
-#endif /* ERST_SMP */
     return DB_ERROR_NONE;
 }
 
@@ -692,7 +669,7 @@ static int db_first_hash(Process *p, DbTable *tbl, Eterm *ret)
 {
     DbTableHash *tb = &tbl->hash;
     Uint ix = 0;
-    erts_smp_rwmtx_t* lck = RLOCK_HASH(tb,ix);
+    erts_rwmtx_t* lck = RLOCK_HASH(tb,ix);
     HashDbTerm* list;
 
     for (;;) {
@@ -725,7 +702,7 @@ static int db_next_hash(Process *p, DbTable *tbl, Eterm key, Eterm *ret)
     HashValue hval;
     Uint ix;
     HashDbTerm* b;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
 
     hval = MAKE_HASH(key);
     lck = RLOCK_HASH(tb,hval);
@@ -772,7 +749,7 @@ int db_put_hash(DbTable *tbl, Eterm obj, int key_clash_fail)
     HashDbTerm** bp;
     HashDbTerm* b;
     HashDbTerm* q;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
     int nitems;
     int ret = DB_ERROR_NONE;
 
@@ -798,7 +775,7 @@ int db_put_hash(DbTable *tbl, Eterm obj, int key_clash_fail)
     if (tb->common.status & DB_SET) {
 	HashDbTerm* bnext = b->next;
 	if (b->hvalue == INVALID_HASH) {
-	    erts_smp_atomic_inc_nob(&tb->common.nitems);
+	    erts_atomic_inc_nob(&tb->common.nitems);
 	}
 	else if (key_clash_fail) {
 	    ret = DB_ERROR_BADKEY;
@@ -826,7 +803,7 @@ int db_put_hash(DbTable *tbl, Eterm obj, int key_clash_fail)
 	do {
 	    if (db_eq(&tb->common,obj,&q->dbterm)) {
 		if (q->hvalue == INVALID_HASH) {
-		    erts_smp_atomic_inc_nob(&tb->common.nitems);
+		    erts_atomic_inc_nob(&tb->common.nitems);
 		    q->hvalue = hval;
 		    if (q != b) { /* must move to preserve key insertion order */
 			*qp = q->next;
@@ -847,7 +824,7 @@ Lnew:
     q->hvalue = hval;
     q->next = b;
     *bp = q;
-    nitems = erts_smp_atomic_inc_read_nob(&tb->common.nitems);
+    nitems = erts_atomic_inc_read_nob(&tb->common.nitems);
     WUNLOCK_HASH(lck);
     {
 	int nactive = NACTIVE(tb);       
@@ -891,7 +868,7 @@ int db_get_hash(Process *p, DbTable *tbl, Eterm key, Eterm *ret)
     HashValue hval;
     int ix;
     HashDbTerm* b;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
 
     hval = MAKE_HASH(key);
     lck = RLOCK_HASH(tb,hval);
@@ -917,7 +894,7 @@ static int db_member_hash(DbTable *tbl, Eterm key, Eterm *ret)
     HashValue hval;
     int ix;
     HashDbTerm* b1;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
 
     hval = MAKE_HASH(key);
     ix = hash_to_ix(tb, hval);
@@ -946,7 +923,7 @@ static int db_get_element_hash(Process *p, DbTable *tbl,
     HashValue hval;
     int ix;
     HashDbTerm* b1;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
     int retval;
     
     hval = MAKE_HASH(key);
@@ -1011,7 +988,7 @@ int db_erase_hash(DbTable *tbl, Eterm key, Eterm *ret)
     int ix;
     HashDbTerm** bp;
     HashDbTerm* b;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
     int nitems_diff = 0;
 
     hval = MAKE_HASH(key);
@@ -1043,7 +1020,7 @@ int db_erase_hash(DbTable *tbl, Eterm key, Eterm *ret)
     }
     WUNLOCK_HASH(lck);
     if (nitems_diff) {
-	erts_smp_atomic_add_nob(&tb->common.nitems, nitems_diff);
+	erts_atomic_add_nob(&tb->common.nitems, nitems_diff);
 	try_shrink(tb);
     }
     *ret = am_true;
@@ -1060,7 +1037,7 @@ static int db_erase_object_hash(DbTable *tbl, Eterm object, Eterm *ret)
     int ix;
     HashDbTerm** bp;
     HashDbTerm* b;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
     int nitems_diff = 0;
     int nkeys = 0;
     Eterm key;
@@ -1101,7 +1078,7 @@ static int db_erase_object_hash(DbTable *tbl, Eterm object, Eterm *ret)
     }
     WUNLOCK_HASH(lck);
     if (nitems_diff) {
-	erts_smp_atomic_add_nob(&tb->common.nitems, nitems_diff);
+	erts_atomic_add_nob(&tb->common.nitems, nitems_diff);
 	try_shrink(tb);
     }
     *ret = am_true;
@@ -1112,7 +1089,7 @@ static int db_erase_object_hash(DbTable *tbl, Eterm object, Eterm *ret)
 static int db_slot_hash(Process *p, DbTable *tbl, Eterm slot_term, Eterm *ret)
 {
     DbTableHash *tb = &tbl->hash;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
     Sint slot;
     int retval;
     int nactive;
@@ -1227,18 +1204,13 @@ static int match_traverse(Process* p, DbTableHash* tb,
     unsigned current_list_pos = 0; /* Prefound buckets list index */
     Eterm match_res;
     Sint got = 0;                  /* Matched terms counter */
-    erts_smp_rwmtx_t* lck;         /* Slot lock */
+    erts_rwmtx_t* lck;         /* Slot lock */
     int ret_value;
-#ifdef ERTS_SMP
-    erts_smp_rwmtx_t* (*lock_hash_function)(DbTableHash*, HashValue)
+    erts_rwmtx_t* (*lock_hash_function)(DbTableHash*, HashValue)
         = (lock_for_write ? WLOCK_HASH : RLOCK_HASH);
-    void (*unlock_hash_function)(erts_smp_rwmtx_t*)
+    void (*unlock_hash_function)(erts_rwmtx_t*)
         = (lock_for_write ? WUNLOCK_HASH : RUNLOCK_HASH);
-#else
-    #define lock_hash_function(tb, hval) NULL
-    #define unlock_hash_function(lck) ((void)lck)
-#endif
-    Sint (*next_slot_function)(DbTableHash*, Uint, erts_smp_rwmtx_t**)
+    Sint (*next_slot_function)(DbTableHash*, Uint, erts_rwmtx_t**)
         = (lock_for_write ? next_slot_w : next_slot);
 
     if ((ret_value = analyze_pattern(tb, pattern, extra_match_validator, &mpi))
@@ -1356,10 +1328,6 @@ done:
     }
     return ret_value;
 
-#ifndef SMP
-#undef lock_hash_function
-#undef unlock_hash_function
-#endif
 }
 
 /*
@@ -1386,18 +1354,13 @@ static int match_traverse_continue(Process* p, DbTableHash* tb,
                                        */
     HashDbTerm* saved_current; /* Helper to avoid double skip on match */
     Eterm match_res;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
     int ret_value;
-#ifdef ERTS_SMP
-    erts_smp_rwmtx_t* (*lock_hash_function)(DbTableHash*, HashValue)
+    erts_rwmtx_t* (*lock_hash_function)(DbTableHash*, HashValue)
         = (lock_for_write ? WLOCK_HASH : RLOCK_HASH);
-    void (*unlock_hash_function)(erts_smp_rwmtx_t*)
+    void (*unlock_hash_function)(erts_rwmtx_t*)
         = (lock_for_write ? WUNLOCK_HASH : RUNLOCK_HASH);
-#else
-    #define lock_hash_function(tb, hval) NULL
-    #define unlock_hash_function(lck) ((void)lck)
-#endif
-    Sint (*next_slot_function)(DbTableHash* tb, Uint ix, erts_smp_rwmtx_t** lck_ptr)
+    Sint (*next_slot_function)(DbTableHash* tb, Uint ix, erts_rwmtx_t** lck_ptr)
         = (lock_for_write ? next_slot_w : next_slot);
 
     if (got < 0) {
@@ -1472,10 +1435,6 @@ done:
      */
     return ret_value;
 
-#ifndef SMP
-#undef lock_hash_function
-#undef unlock_hash_function
-#endif
 }
 
 
@@ -2008,7 +1967,7 @@ static int mtraversal_select_delete_on_match_res(void* context_ptr, Sint slot_ix
         *current_ptr = (*current_ptr)->next; // replace pointer to term using next
         free_term(sd_context_ptr->tb, del);
     }
-    erts_smp_atomic_dec_nob(&sd_context_ptr->tb->common.nitems);
+    erts_atomic_dec_nob(&sd_context_ptr->tb->common.nitems);
 
     return 1;
 }
@@ -2048,11 +2007,7 @@ static int db_select_delete_hash(Process *p, DbTable *tbl, Eterm tid, Eterm patt
     sd_context.tid = tid;
     sd_context.hp = NULL;
     sd_context.prev_continuation_tptr = NULL;
-#ifdef ERTS_SMP
     sd_context.fixated_by_me = sd_context.tb->common.is_thread_safe ? 0 : 1; /* TODO: something nicer */
-#else
-    sd_context.fixated_by_me = 0;
-#endif
     sd_context.last_pseudo_delete = (Uint) -1;
 
     return match_traverse(
@@ -2251,7 +2206,7 @@ static int db_take_hash(Process *p, DbTable *tbl, Eterm key, Eterm *ret)
     DbTableHash *tb = &tbl->hash;
     HashDbTerm **bp, *b;
     HashValue hval = MAKE_HASH(key);
-    erts_smp_rwmtx_t *lck = WLOCK_HASH(tb, hval);
+    erts_rwmtx_t *lck = WLOCK_HASH(tb, hval);
     int ix = hash_to_ix(tb, hval);
     int nitems_diff = 0;
 
@@ -2280,7 +2235,7 @@ static int db_take_hash(Process *p, DbTable *tbl, Eterm key, Eterm *ret)
     }
     WUNLOCK_HASH(lck);
     if (nitems_diff) {
-        erts_smp_atomic_add_nob(&tb->common.nitems, nitems_diff);
+        erts_atomic_add_nob(&tb->common.nitems, nitems_diff);
         try_shrink(tb);
     }
     return DB_ERROR_NONE;
@@ -2302,7 +2257,7 @@ int db_mark_all_deleted_hash(DbTable *tbl)
     HashDbTerm* list;
     int i;
 
-    ERTS_SMP_LC_ASSERT(IS_TAB_WLOCKED(tb));
+    ERTS_LC_ASSERT(IS_TAB_WLOCKED(tb));
 
     for (i = 0; i < NACTIVE(tb); i++) {
 	if ((list = BUCKET(tb,i)) != NULL) {
@@ -2313,7 +2268,7 @@ int db_mark_all_deleted_hash(DbTable *tbl)
 	    }while(list != NULL);
 	}
     }
-    erts_smp_atomic_set_nob(&tb->common.nitems, 0);    
+    erts_atomic_set_nob(&tb->common.nitems, 0);
     return DB_ERROR_NONE;
 }
 
@@ -2327,7 +2282,6 @@ static void db_print_hash(fmtfn_t to, void *to_arg, int show, DbTable *tbl)
 
     erts_print(to, to_arg, "Buckets: %d\n", NACTIVE(tb));
 
-#ifdef ERTS_SMP
     i = tbl->common.is_thread_safe;
     /* If crash dumping we set table to thread safe in order to
        avoid taking any locks */
@@ -2337,9 +2291,6 @@ static void db_print_hash(fmtfn_t to, void *to_arg, int show, DbTable *tbl)
     db_calc_stats_hash(&tbl->hash, &stats);
 
     tbl->common.is_thread_safe = i;
-#else
-    db_calc_stats_hash(&tbl->hash, &stats);
-#endif
 
     erts_print(to, to_arg, "Chain Length Avg: %f\n", stats.avg_chain_len);
     erts_print(to, to_arg, "Chain Length Max: %d\n", stats.max_chain_len);
@@ -2391,8 +2342,8 @@ static int db_free_table_hash(DbTable *tbl)
 static SWord db_free_table_continue_hash(DbTable *tbl, SWord reds)
 {
     DbTableHash *tb = &tbl->hash;
-    FixedDeletion* fixdel = (FixedDeletion*) erts_smp_atomic_read_acqb(&tb->fixdel);
-    ERTS_SMP_LC_ASSERT(IS_TAB_WLOCKED(tb) || (tb->common.status & DB_DELETE));
+    FixedDeletion* fixdel = (FixedDeletion*) erts_atomic_read_acqb(&tb->fixdel);
+    ERTS_LC_ASSERT(IS_TAB_WLOCKED(tb) || (tb->common.status & DB_DELETE));
 
     while (fixdel != NULL) {
 	FixedDeletion *fx = fixdel;
@@ -2404,11 +2355,11 @@ static SWord db_free_table_continue_hash(DbTable *tbl, SWord reds)
 		     sizeof(FixedDeletion));
 	ERTS_ETS_MISC_MEM_ADD(-sizeof(FixedDeletion));
 	if (--reds < 0) {
-	    erts_smp_atomic_set_relb(&tb->fixdel, (erts_aint_t)fixdel);
+	    erts_atomic_set_relb(&tb->fixdel, (erts_aint_t)fixdel);
 	    return reds;		/* Not done */
 	}
     }
-    erts_smp_atomic_set_relb(&tb->fixdel, (erts_aint_t)NULL);
+    erts_atomic_set_relb(&tb->fixdel, (erts_aint_t)NULL);
 
     while(tb->nslots != 0) {
 	reds -= EXT_SEGSZ/64 + free_seg(tb, 1);
@@ -2420,7 +2371,6 @@ static SWord db_free_table_continue_hash(DbTable *tbl, SWord reds)
 	    return reds;	/* Not done */
 	}
     }
-#ifdef ERTS_SMP
     if (tb->locks != NULL) {
 	int i;
 	for (i=0; i<DB_HASH_LOCK_CNT; ++i) {
@@ -2430,8 +2380,7 @@ static SWord db_free_table_continue_hash(DbTable *tbl, SWord reds)
 		     (void*)tb->locks, sizeof(DbTableHashFineLocks));
 	tb->locks = NULL;
     }
-#endif    
-    ASSERT(erts_smp_atomic_read_nob(&tb->common.memory_size) == sizeof(DbTable));
+    ASSERT(erts_atomic_read_nob(&tb->common.memory_size) == sizeof(DbTable));
     return reds;			/* Done */
 }
 
@@ -2530,7 +2479,7 @@ static int analyze_pattern(DbTableHash *tb, Eterm pattern,
 		if (!db_has_variable(key)) {   /* Bound key */
 		    int ix, search_slot;
 		    HashDbTerm** bp;
-		    erts_smp_rwmtx_t* lck;
+		    erts_rwmtx_t* lck;
 		    hval = MAKE_HASH(key);
 		    lck = RLOCK_HASH(tb,hval);
 		    ix = hash_to_ix(tb, hval);
@@ -2634,14 +2583,12 @@ static void alloc_seg(DbTableHash *tb)
     tb->nslots += EXT_SEGSZ;
 }
 
-#ifdef ERTS_SMP
 static void dealloc_ext_segtab(void* lop_data)
 {
     struct ext_segtab* est = (struct ext_segtab*) lop_data;
 
     erts_free(ERTS_ALC_T_DB_SEG, est);
 }
-#endif
 
 /* Shrink table by freeing the top segment
 ** free_records: 1=free any records in segment, 0=assume segment is empty 
@@ -2680,7 +2627,6 @@ static int free_seg(DbTableHash *tb, int free_records)
             SET_SEGTAB(tb, est->prev_segtab);
             tb->nsegs = est->prev_nsegs;
 
-#ifdef ERTS_SMP
             if (!tb->common.is_thread_safe) {
                 /*
                  * Table is doing a graceful shrink operation and we must avoid
@@ -2698,7 +2644,6 @@ static int free_seg(DbTableHash *tb, int free_records)
                                                         sz);
             }
             else
-#endif
                 erts_db_free(ERTS_ALC_T_DB_SEG, (DbTable*)tb, est,
                              SIZEOF_EXT_SEGTAB(est->nsegs));
         }
@@ -2759,22 +2704,18 @@ static Eterm build_term_list(Process* p, HashDbTerm* ptr1, HashDbTerm* ptr2,
 static ERTS_INLINE int
 begin_resizing(DbTableHash* tb)
 {
-#ifdef ERTS_SMP
     if (DB_USING_FINE_LOCKING(tb))
 	return !erts_atomic_xchg_acqb(&tb->is_resizing, 1);
     else
         ERTS_LC_ASSERT(erts_lc_rwmtx_is_rwlocked(&tb->common.rwlock));
-#endif
     return 1;
 }
 
 static ERTS_INLINE void
 done_resizing(DbTableHash* tb)
 {
-#ifdef ERTS_SMP
     if (DB_USING_FINE_LOCKING(tb))
 	erts_atomic_set_relb(&tb->is_resizing, 0);
-#endif
 }
 
 /* Grow table with one or more new buckets.
@@ -2785,7 +2726,7 @@ static void grow(DbTableHash* tb, int nitems)
     HashDbTerm** pnext;
     HashDbTerm** to_pnext;
     HashDbTerm* p;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
     int nactive;
     int from_ix, to_ix;
     int szm;
@@ -2807,7 +2748,7 @@ static void grow(DbTableHash* tb, int nitems)
         }
         ASSERT(nactive < tb->nslots);
 
-        szm = erts_smp_atomic_read_nob(&tb->szm);
+        szm = erts_atomic_read_nob(&tb->szm);
         if (nactive <= szm) {
             from_ix = nactive & (szm >> 1);
         } else {
@@ -2818,7 +2759,7 @@ static void grow(DbTableHash* tb, int nitems)
         to_ix = nactive;
 
         lck = WLOCK_HASH(tb, from_ix);
-        ERTS_SMP_ASSERT(lck == GET_LOCK_MAYBE(tb,to_ix));
+        ERTS_ASSERT(lck == GET_LOCK_MAYBE(tb,to_ix));
         /* Now a final double check (with the from_ix lock held)
          * that we did not get raced by a table fixer.
          */
@@ -2826,12 +2767,12 @@ static void grow(DbTableHash* tb, int nitems)
             WUNLOCK_HASH(lck);
             goto abort;
         }
-        erts_smp_atomic_set_nob(&tb->nactive, ++nactive);
+        erts_atomic_set_nob(&tb->nactive, ++nactive);
         if (from_ix == 0) {
             if (DB_USING_FINE_LOCKING(tb))
-                erts_smp_atomic_set_relb(&tb->szm, szm);
+                erts_atomic_set_relb(&tb->szm, szm);
             else
-                erts_smp_atomic_set_nob(&tb->szm, szm);
+                erts_atomic_set_nob(&tb->szm, szm);
         }
         done_resizing(tb);
 
@@ -2879,7 +2820,7 @@ static void shrink(DbTableHash* tb, int nitems)
     HashDbTerm** src_bp;
     HashDbTerm** dst_bp;
     HashDbTerm** bp;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
     int src_ix, dst_ix, low_szm;
     int nactive;
     int loop_limit = 5;
@@ -2892,13 +2833,13 @@ static void shrink(DbTableHash* tb, int nitems)
             goto abort; /* already done (race) */
         }
         src_ix = nactive - 1;
-        low_szm = erts_smp_atomic_read_nob(&tb->szm) >> 1;
+        low_szm = erts_atomic_read_nob(&tb->szm) >> 1;
         dst_ix = src_ix & low_szm;
 
         ASSERT(dst_ix < src_ix);
         ASSERT(nactive > FIRST_SEGSZ);
         lck = WLOCK_HASH(tb, dst_ix);
-        ERTS_SMP_ASSERT(lck == GET_LOCK_MAYBE(tb,src_ix));
+        ERTS_ASSERT(lck == GET_LOCK_MAYBE(tb,src_ix));
         /* Double check for racing table fixers */
         if (IS_FIXED(tb)) {
             WUNLOCK_HASH(lck);
@@ -2927,9 +2868,9 @@ static void shrink(DbTableHash* tb, int nitems)
         *src_bp = NULL;
 
         nactive = src_ix;
-        erts_smp_atomic_set_nob(&tb->nactive, nactive);
+        erts_atomic_set_nob(&tb->nactive, nactive);
         if (dst_ix == 0) {
-            erts_smp_atomic_set_relb(&tb->szm, low_szm);
+            erts_atomic_set_relb(&tb->szm, low_szm);
         }
         WUNLOCK_HASH(lck);
 
@@ -2964,12 +2905,12 @@ static HashDbTerm* search_list(DbTableHash* tb, Eterm key,
 /* It return the next live object in a table, NULL if no more */
 /* In-bucket: RLOCKED */
 /* Out-bucket: RLOCKED unless NULL */
-static HashDbTerm* next(DbTableHash *tb, Uint *iptr, erts_smp_rwmtx_t** lck_ptr,
+static HashDbTerm* next(DbTableHash *tb, Uint *iptr, erts_rwmtx_t** lck_ptr,
 			HashDbTerm *list)
 {
     int i;
 
-    ERTS_SMP_LC_ASSERT(IS_HASH_RLOCKED(tb,*iptr));
+    ERTS_LC_ASSERT(IS_HASH_RLOCKED(tb,*iptr));
 
     for (list = list->next; list != NULL; list = list->next) {
 	if (list->hvalue != INVALID_HASH)
@@ -2999,7 +2940,7 @@ db_lookup_dbterm_hash(Process *p, DbTable *tbl, Eterm key, Eterm obj,
     DbTableHash *tb = &tbl->hash;
     HashValue hval;
     HashDbTerm **bp, *b;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
     int flags = 0;
 
     ASSERT(tb->common.status & DB_SET);
@@ -3055,7 +2996,7 @@ db_lookup_dbterm_hash(Process *p, DbTable *tbl, Eterm key, Eterm obj,
             q->next = next;
             q->hvalue = hval;
             *bp = b = q;
-            erts_smp_atomic_inc_nob(&tb->common.nitems);
+            erts_atomic_inc_nob(&tb->common.nitems);
         }
 
         HRelease(p, hend, htop);
@@ -3081,10 +3022,10 @@ db_finalize_dbterm_hash(int cret, DbUpdateHandle* handle)
     DbTableHash *tb = &tbl->hash;
     HashDbTerm **bp = (HashDbTerm **) handle->bp;
     HashDbTerm *b = *bp;
-    erts_smp_rwmtx_t* lck = (erts_smp_rwmtx_t*) handle->lck;
+    erts_rwmtx_t* lck = (erts_rwmtx_t*) handle->lck;
     HashDbTerm* free_me = NULL;
 
-    ERTS_SMP_LC_ASSERT(IS_HASH_WLOCKED(tb, lck));  /* locked by db_lookup_dbterm_hash */
+    ERTS_LC_ASSERT(IS_HASH_WLOCKED(tb, lck));  /* locked by db_lookup_dbterm_hash */
 
     ASSERT((&b->dbterm == handle->dbterm) == !(tb->common.compress && handle->flags & DB_MUST_RESIZE));
 
@@ -3098,7 +3039,7 @@ db_finalize_dbterm_hash(int cret, DbUpdateHandle* handle)
         }
 
         WUNLOCK_HASH(lck);
-        erts_smp_atomic_dec_nob(&tb->common.nitems);
+        erts_atomic_dec_nob(&tb->common.nitems);
         try_shrink(tb);
     } else {
         if (handle->flags & DB_MUST_RESIZE) {
@@ -3107,7 +3048,7 @@ db_finalize_dbterm_hash(int cret, DbUpdateHandle* handle)
         }
         if (handle->flags & DB_INC_TRY_GROW) {
             int nactive;
-            int nitems = erts_smp_atomic_inc_read_nob(&tb->common.nitems);
+            int nitems = erts_atomic_inc_read_nob(&tb->common.nitems);
             WUNLOCK_HASH(lck);
             nactive = NACTIVE(tb);
 
@@ -3135,7 +3076,7 @@ static int db_delete_all_objects_hash(Process* p, DbTable* tbl)
     } else {
 	db_free_table_hash(tbl);
 	db_create_hash(p, tbl);
-	erts_smp_atomic_set_nob(&tbl->hash.common.nitems, 0);
+	erts_atomic_set_nob(&tbl->hash.common.nitems, 0);
     }
     return 0;
 }
@@ -3165,7 +3106,7 @@ void db_foreach_offheap_hash(DbTable *tbl,
 void db_calc_stats_hash(DbTableHash* tb, DbHashStats* stats)
 {
     HashDbTerm* b;
-    erts_smp_rwmtx_t* lck;
+    erts_rwmtx_t* lck;
     int sum = 0;
     int sq_sum = 0;
     int kept_items = 0;
diff --git a/erts/emulator/beam/erl_db_hash.h b/erts/emulator/beam/erl_db_hash.h
index 523ed7860e..7d27609825 100644
--- a/erts/emulator/beam/erl_db_hash.h
+++ b/erts/emulator/beam/erl_db_hash.h
@@ -42,8 +42,8 @@ typedef struct hash_db_term {
 
 typedef struct db_table_hash_fine_locks {
     union {
-	erts_smp_rwmtx_t lck;
-	byte _cache_line_alignment[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(erts_smp_rwmtx_t))];
+	erts_rwmtx_t lck;
+	byte _cache_line_alignment[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(erts_rwmtx_t))];
     }lck_vec[DB_HASH_LOCK_CNT];
 } DbTableHashFineLocks;
 
@@ -51,10 +51,10 @@ typedef struct db_table_hash {
     DbTableCommon common;
 
     /* SMP: szm and nactive are write-protected by is_resizing or table write lock */
-    erts_smp_atomic_t szm;     /* current size mask. */
-    erts_smp_atomic_t nactive; /* Number of "active" slots */
+    erts_atomic_t szm;     /* current size mask. */
+    erts_atomic_t nactive; /* Number of "active" slots */
 
-    erts_smp_atomic_t segtab;  /* The segment table (struct segment**) */
+    erts_atomic_t segtab;  /* The segment table (struct segment**) */
     struct segment* first_segtab[1];
 
     /* SMP: nslots and nsegs are protected by is_resizing or table write lock */
@@ -62,11 +62,9 @@ typedef struct db_table_hash {
     int nsegs;        /* Size of segment table */
 
     /* List of slots where elements have been deleted while table was fixed */
-    erts_smp_atomic_t fixdel;  /* (FixedDeletion*) */	
-#ifdef ERTS_SMP
-    erts_smp_atomic_t is_resizing; /* grow/shrink in progress */
+    erts_atomic_t fixdel;  /* (FixedDeletion*) */
+    erts_atomic_t is_resizing; /* grow/shrink in progress */
     DbTableHashFineLocks* locks;
-#endif
 } DbTableHash;
 
 
diff --git a/erts/emulator/beam/erl_db_tree.c b/erts/emulator/beam/erl_db_tree.c
index 7c80e92e50..5a276b9d88 100644
--- a/erts/emulator/beam/erl_db_tree.c
+++ b/erts/emulator/beam/erl_db_tree.c
@@ -50,7 +50,7 @@
 #include "erl_db_tree.h"
 
 #define GETKEY_WITH_POS(Keypos, Tplp) (*((Tplp) + Keypos))
-#define NITEMS(tb) ((int)erts_smp_atomic_read_nob(&(tb)->common.nitems))
+#define NITEMS(tb) ((int)erts_atomic_read_nob(&(tb)->common.nitems))
 
 /*
 ** A stack of this size is enough for an AVL tree with more than
@@ -91,7 +91,7 @@
 */
 static DbTreeStack* get_static_stack(DbTableTree* tb)
 {
-    if (!erts_smp_atomic_xchg_acqb(&tb->is_stack_busy, 1)) {
+    if (!erts_atomic_xchg_acqb(&tb->is_stack_busy, 1)) {
 	return &tb->static_stack;
     }
     return NULL;
@@ -103,7 +103,7 @@ static DbTreeStack* get_static_stack(DbTableTree* tb)
 static DbTreeStack* get_any_stack(DbTableTree* tb)
 {
     DbTreeStack* stack;
-    if (!erts_smp_atomic_xchg_acqb(&tb->is_stack_busy, 1)) {
+    if (!erts_atomic_xchg_acqb(&tb->is_stack_busy, 1)) {
 	return &tb->static_stack;
     }
     stack = erts_db_alloc(ERTS_ALC_T_DB_STK, (DbTable *) tb,
@@ -117,8 +117,8 @@ static DbTreeStack* get_any_stack(DbTableTree* tb)
 static void release_stack(DbTableTree* tb, DbTreeStack* stack)
 {
     if (stack == &tb->static_stack) {
-	ASSERT(erts_smp_atomic_read_nob(&tb->is_stack_busy) == 1);
-	erts_smp_atomic_set_relb(&tb->is_stack_busy, 0);
+	ASSERT(erts_atomic_read_nob(&tb->is_stack_busy) == 1);
+	erts_atomic_set_relb(&tb->is_stack_busy, 0);
     }
     else {
 	erts_db_free(ERTS_ALC_T_DB_STK, (DbTable *) tb,
@@ -514,7 +514,7 @@ int db_create_tree(Process *p, DbTable *tbl)
 					   sizeof(TreeDbTerm *) * STACK_NEED);
     tb->static_stack.pos = 0;
     tb->static_stack.slot = 0;
-    erts_smp_atomic_init_nob(&tb->is_stack_busy, 0);
+    erts_atomic_init_nob(&tb->is_stack_busy, 0);
     tb->deletion = 0;
     return DB_ERROR_NONE;
 }
@@ -643,8 +643,8 @@ static int db_put_tree(DbTable *tbl, Eterm obj, int key_clash_fail)
     for (;;)
 	if (!*this) { /* Found our place */
 	    state = 1;
-	    if (erts_smp_atomic_inc_read_nob(&tb->common.nitems) >= TREE_MAX_ELEMENTS) {
-		erts_smp_atomic_dec_nob(&tb->common.nitems);
+	    if (erts_atomic_inc_read_nob(&tb->common.nitems) >= TREE_MAX_ELEMENTS) {
+		erts_atomic_dec_nob(&tb->common.nitems);
 		return DB_ERROR_SYSRES;
 	    }
 	    *this = new_dbterm(tb, obj);
@@ -1605,7 +1605,7 @@ static int db_select_delete_continue_tree(Process *p,
     sc.max = 1000;
     sc.keypos = tb->common.keypos;
 
-    ASSERT(!erts_smp_atomic_read_nob(&tb->is_stack_busy));
+    ASSERT(!erts_atomic_read_nob(&tb->is_stack_busy));
     traverse_backwards(tb, &tb->static_stack, lastkey, &doit_select_delete, &sc);
 
     BUMP_REDS(p, 1000 - sc.max);
@@ -2017,7 +2017,7 @@ static SWord db_free_table_continue_tree(DbTable *tbl, SWord reds)
 		     (DbTable *) tb,
 		     (void *) tb->static_stack.array,
 		     sizeof(TreeDbTerm *) * STACK_NEED);
-	ASSERT(erts_smp_atomic_read_nob(&tb->common.memory_size)
+	ASSERT(erts_atomic_read_nob(&tb->common.memory_size)
 	       == sizeof(DbTable));
     }
     return reds;
@@ -2027,7 +2027,7 @@ static int db_delete_all_objects_tree(Process* p, DbTable* tbl)
 {
     db_free_table_tree(tbl);
     db_create_tree(p, tbl);
-    erts_smp_atomic_set_nob(&tbl->tree.common.nitems, 0);
+    erts_atomic_set_nob(&tbl->tree.common.nitems, 0);
     return 0;
 }
 
@@ -2107,7 +2107,7 @@ static TreeDbTerm *linkout_tree(DbTableTree *tb, Eterm key) {
 		tstack[tpos++] = this;
 		state = delsub(this);
 	    }
-	    erts_smp_atomic_dec_nob(&tb->common.nitems);
+	    erts_atomic_dec_nob(&tb->common.nitems);
 	    break;
 	}
     }
@@ -2174,7 +2174,7 @@ static TreeDbTerm *linkout_object_tree(DbTableTree *tb,
 		tstack[tpos++] = this;
 		state = delsub(this);
 	    }
-	    erts_smp_atomic_dec_nob(&tb->common.nitems);
+	    erts_atomic_dec_nob(&tb->common.nitems);
 	    break;
 	}
     }
diff --git a/erts/emulator/beam/erl_db_tree.h b/erts/emulator/beam/erl_db_tree.h
index 72749ead1e..dc1b93d410 100644
--- a/erts/emulator/beam/erl_db_tree.h
+++ b/erts/emulator/beam/erl_db_tree.h
@@ -41,7 +41,7 @@ typedef struct db_table_tree {
     /* Tree-specific fields */
     TreeDbTerm *root;         /* The tree root */
     Uint deletion;		/* Being deleted */
-    erts_smp_atomic_t is_stack_busy;
+    erts_atomic_t is_stack_busy;
     DbTreeStack static_stack;
 } DbTableTree;
 
diff --git a/erts/emulator/beam/erl_db_util.c b/erts/emulator/beam/erl_db_util.c
index 13eacaa8a9..e017b9552b 100644
--- a/erts/emulator/beam/erl_db_util.c
+++ b/erts/emulator/beam/erl_db_util.c
@@ -170,7 +170,7 @@ static Eterm
 set_match_trace(Process *tracee_p, Eterm fail_term, ErtsTracer tracer,
 		Uint d_flags, Uint e_flags) {
 
-    ERTS_SMP_LC_ASSERT(
+    ERTS_LC_ASSERT(
         ERTS_PROC_LOCKS_ALL == erts_proc_lc_my_proc_locks(tracee_p)
         || erts_thr_progress_is_blocking());
 
@@ -361,11 +361,7 @@ typedef struct {
 } ErtsMatchPseudoProcess;
 
 
-#ifdef ERTS_SMP
-static erts_smp_tsd_key_t match_pseudo_process_key;
-#else
-static ErtsMatchPseudoProcess *match_pseudo_process;
-#endif
+static erts_tsd_key_t match_pseudo_process_key;
 
 static ERTS_INLINE void
 cleanup_match_pseudo_process(ErtsMatchPseudoProcess *mpsp, int keep_heap)
@@ -414,32 +410,27 @@ static ERTS_INLINE ErtsMatchPseudoProcess *
 get_match_pseudo_process(Process *c_p, Uint heap_size)
 {
     ErtsMatchPseudoProcess *mpsp;
-#ifdef ERTS_SMP
     ErtsSchedulerData *esdp;
 
     esdp = c_p ? c_p->scheduler_data : erts_get_scheduler_data();
 
     mpsp = esdp ? esdp->match_pseudo_process :
-        (ErtsMatchPseudoProcess*) erts_smp_tsd_get(match_pseudo_process_key);
+        (ErtsMatchPseudoProcess*) erts_tsd_get(match_pseudo_process_key);
 
     if (mpsp) {
-        ASSERT(mpsp == erts_smp_tsd_get(match_pseudo_process_key));
+        ASSERT(mpsp == erts_tsd_get(match_pseudo_process_key));
         ASSERT(mpsp->process.scheduler_data == esdp);
 	cleanup_match_pseudo_process(mpsp, 0);
     }
     else {
-	ASSERT(erts_smp_tsd_get(match_pseudo_process_key) == NULL);
+	ASSERT(erts_tsd_get(match_pseudo_process_key) == NULL);
 	mpsp = create_match_pseudo_process();
         if (esdp) {
             esdp->match_pseudo_process = (void *) mpsp;
         }
         mpsp->process.scheduler_data = esdp;
-	erts_smp_tsd_set(match_pseudo_process_key, (void *) mpsp);
+	erts_tsd_set(match_pseudo_process_key, (void *) mpsp);
     }
-#else
-    mpsp = match_pseudo_process;
-    cleanup_match_pseudo_process(mpsp, 0);
-#endif
     if (heap_size > ERTS_DEFAULT_MS_HEAP_SIZE*sizeof(Eterm)) {
 	mpsp->u.heap = (Eterm*) erts_alloc(ERTS_ALC_T_DB_MS_RUN_HEAP, heap_size);
     }
@@ -449,31 +440,25 @@ get_match_pseudo_process(Process *c_p, Uint heap_size)
     return mpsp;
 }
 
-#ifdef ERTS_SMP
 static void
 destroy_match_pseudo_process(void)
 {
     ErtsMatchPseudoProcess *mpsp;
-    mpsp = (ErtsMatchPseudoProcess *)erts_smp_tsd_get(match_pseudo_process_key);
+    mpsp = (ErtsMatchPseudoProcess *)erts_tsd_get(match_pseudo_process_key);
     if (mpsp) {
 	cleanup_match_pseudo_process(mpsp, 0);
 	erts_free(ERTS_ALC_T_DB_MS_PSDO_PROC, (void *) mpsp);
-	erts_smp_tsd_set(match_pseudo_process_key, (void *) NULL);
+	erts_tsd_set(match_pseudo_process_key, (void *) NULL);
     }
 }
-#endif
 
 static
 void
 match_pseudo_process_init(void)
 {
-#ifdef ERTS_SMP
-    erts_smp_tsd_key_create(&match_pseudo_process_key,
+    erts_tsd_key_create(&match_pseudo_process_key,
 			    "erts_match_pseudo_process_key");
-    erts_smp_install_exit_handler(destroy_match_pseudo_process);
-#else
-    match_pseudo_process = create_match_pseudo_process();
-#endif
+    erts_thr_install_exit_handler(destroy_match_pseudo_process);
 }
 
 void
@@ -484,7 +469,7 @@ erts_match_set_release_result(Process* c_p)
 
 /* The trace control word. */
 
-static erts_smp_atomic32_t trace_control_word;
+static erts_atomic32_t trace_control_word;
 
 /* This needs to be here, before the bif table... */
 
@@ -923,7 +908,7 @@ static void db_free_tmp_uncompressed(DbTerm* obj);
 */
 BIF_RETTYPE db_get_trace_control_word(Process *p)
 {
-    Uint32 tcw = (Uint32) erts_smp_atomic32_read_acqb(&trace_control_word);
+    Uint32 tcw = (Uint32) erts_atomic32_read_acqb(&trace_control_word);
     BIF_RET(erts_make_integer((Uint) tcw, p));
 }
 
@@ -941,7 +926,7 @@ BIF_RETTYPE db_set_trace_control_word(Process *p, Eterm new)
     if (val != ((Uint32)val))
 	BIF_ERROR(p, BADARG);
 
-    old_tcw = (Uint32) erts_smp_atomic32_xchg_relb(&trace_control_word,
+    old_tcw = (Uint32) erts_atomic32_xchg_relb(&trace_control_word,
 						   (erts_aint32_t) val);
     BIF_RET(erts_make_integer((Uint) old_tcw, p));
 }
@@ -1466,7 +1451,7 @@ void db_initialize_util(void){
 	  sizeof(DMCGuardBif), 
 	  (int (*)(const void *, const void *)) &cmp_guard_bif);
     match_pseudo_process_init();
-    erts_smp_atomic32_init_nob(&trace_control_word, 0);
+    erts_atomic32_init_nob(&trace_control_word, 0);
 }
 
 
@@ -2528,9 +2513,9 @@ restart:
         case matchEnableTrace:
             ASSERT(c_p == self);
 	    if ( (n = erts_trace_flag2bit(esp[-1]))) {
-                erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+                erts_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 		set_tracee_flags(c_p, ERTS_TRACER(c_p), 0, n);
-                erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+                erts_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 		esp[-1] = am_true;
 	    } else {
 		esp[-1] = FAIL_TERM;
@@ -2545,9 +2530,9 @@ restart:
 		    /* Always take over the tracer of the current process */
 		    set_tracee_flags(tmpp, ERTS_TRACER(c_p), 0, n);
                     if (tmpp == c_p)
-                        erts_smp_proc_unlock(tmpp, ERTS_PROC_LOCKS_ALL_MINOR);
+                        erts_proc_unlock(tmpp, ERTS_PROC_LOCKS_ALL_MINOR);
                     else
-                        erts_smp_proc_unlock(tmpp, ERTS_PROC_LOCKS_ALL);
+                        erts_proc_unlock(tmpp, ERTS_PROC_LOCKS_ALL);
                     esp[-1] = am_true;
 		}
 	    }
@@ -2555,9 +2540,9 @@ restart:
         case matchDisableTrace:
             ASSERT(c_p == self);
 	    if ( (n = erts_trace_flag2bit(esp[-1]))) {
-                erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+                erts_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 		set_tracee_flags(c_p, ERTS_TRACER(c_p), n, 0);
-                erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+                erts_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 		esp[-1] = am_true;
 	    } else {
 		esp[-1] = FAIL_TERM;
@@ -2572,9 +2557,9 @@ restart:
 		    /* Always take over the tracer of the current process */
 		    set_tracee_flags(tmpp, ERTS_TRACER(c_p), n, 0);
                     if (tmpp == c_p)
-                        erts_smp_proc_unlock(tmpp, ERTS_PROC_LOCKS_ALL_MINOR);
+                        erts_proc_unlock(tmpp, ERTS_PROC_LOCKS_ALL_MINOR);
                     else
-                        erts_smp_proc_unlock(tmpp, ERTS_PROC_LOCKS_ALL);
+                        erts_proc_unlock(tmpp, ERTS_PROC_LOCKS_ALL);
                     esp[-1] = am_true;
 		}
 	    }
@@ -2598,14 +2583,14 @@ restart:
 	    if (in_flags & ERTS_PAM_IGNORE_TRACE_SILENT)
 	      break;
 	    if (*esp == am_true) {
-		erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+		erts_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 		ERTS_TRACE_FLAGS(c_p) |= F_TRACE_SILENT;
-		erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+		erts_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 	    }
 	    else if (*esp == am_false) {
-		erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+		erts_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 		ERTS_TRACE_FLAGS(c_p) &= ~F_TRACE_SILENT;
-		erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+		erts_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 	    }
 	    break;
         case matchTrace2:
@@ -2634,10 +2619,10 @@ restart:
                     ERTS_TRACER_CLEAR(&tracer);
 		    break;
 		}
-		erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+		erts_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 		(--esp)[-1] = set_match_trace(c_p, FAIL_TERM, tracer,
 					      d_flags, e_flags);
-		erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+		erts_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
                 ERTS_TRACER_CLEAR(&tracer);
 	    }
 	    break;
@@ -2667,13 +2652,13 @@ restart:
 		if (tmpp == c_p) {
 		    (--esp)[-1] = set_match_trace(c_p, FAIL_TERM, tracer,
 						  d_flags, e_flags);
-		    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+		    erts_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 		} else {
-		    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+		    erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
 		    (--esp)[-1] = set_match_trace(tmpp, FAIL_TERM, tracer,
 						  d_flags, e_flags);
-		    erts_smp_proc_unlock(tmpp, ERTS_PROC_LOCKS_ALL);
-		    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+		    erts_proc_unlock(tmpp, ERTS_PROC_LOCKS_ALL);
+		    erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
 		}
                 ERTS_TRACER_CLEAR(&tracer);
 	    }
@@ -3277,7 +3262,7 @@ void db_cleanup_offheap_comp(DbTerm* obj)
 	    break;
 	case FUN_SUBTAG:
 	    ASSERT(u.pb != &tmp);
-	    if (erts_smp_refc_dectest(&u.fun->fe->refc, 0) == 0) {
+	    if (erts_refc_dectest(&u.fun->fe->refc, 0) == 0) {
 		erts_erase_fun_entry(u.fun->fe);
 	    }
 	    break;
diff --git a/erts/emulator/beam/erl_db_util.h b/erts/emulator/beam/erl_db_util.h
index 7ce104a84c..6b126f35d6 100644
--- a/erts/emulator/beam/erl_db_util.h
+++ b/erts/emulator/beam/erl_db_util.h
@@ -240,16 +240,14 @@ typedef struct {
  */
 
 typedef struct db_table_common {
-    erts_smp_refc_t refc;     /* reference count of table struct */
-    erts_smp_refc_t fix_count;/* fixation counter */
+    erts_refc_t refc;     /* reference count of table struct */
+    erts_refc_t fix_count;/* fixation counter */
     DbTableList all;
     DbTableList owned;
-#ifdef ERTS_SMP
-    erts_smp_rwmtx_t rwlock;  /* rw lock on table */
-    erts_smp_mtx_t fixlock;   /* Protects fixing_procs and time */
+    erts_rwmtx_t rwlock;  /* rw lock on table */
+    erts_mtx_t fixlock;   /* Protects fixing_procs and time */
     int is_thread_safe;       /* No fine locking inside table needed */
     Uint32 type;              /* table type, *read only* after creation */
-#endif
     Eterm owner;              /* Pid of the creator */
     Eterm heir;               /* Pid of the heir */
     UWord heir_data;          /* To send in ETS-TRANSFER (is_immed or (DbTerm*) */
@@ -257,8 +255,8 @@ typedef struct db_table_common {
     Eterm the_name;           /* an atom */
     Binary *btid;
     DbTableMethod* meth;      /* table methods */
-    erts_smp_atomic_t nitems; /* Total number of items in table */
-    erts_smp_atomic_t memory_size;/* Total memory size. NOTE: in bytes! */
+    erts_atomic_t nitems; /* Total number of items in table */
+    erts_atomic_t memory_size;/* Total memory size. NOTE: in bytes! */
     struct {                  /* Last fixation time */
 	ErtsMonotonicTime monotonic;
 	ErtsMonotonicTime offset;
@@ -291,7 +289,7 @@ typedef struct db_table_common {
 				  (DB_BAG | DB_SET | DB_DUPLICATE_BAG)))
 #define IS_TREE_TABLE(Status) (!!((Status) & \
 				  DB_ORDERED_SET))
-#define NFIXED(T) (erts_smp_refc_read(&(T)->common.fix_count,0))
+#define NFIXED(T) (erts_refc_read(&(T)->common.fix_count,0))
 #define IS_FIXED(T) (NFIXED(T) != 0) 
 
 /*
diff --git a/erts/emulator/beam/erl_driver.h b/erts/emulator/beam/erl_driver.h
index 5ad616fec3..d5379a40d5 100644
--- a/erts/emulator/beam/erl_driver.h
+++ b/erts/emulator/beam/erl_driver.h
@@ -148,14 +148,6 @@ typedef struct _erl_drv_event* ErlDrvEvent; /* An event to be selected on. */
 typedef struct _erl_drv_port* ErlDrvPort; /* A port descriptor. */
 typedef struct _erl_drv_port* ErlDrvThreadData; /* Thread data. */
 
-#if !defined(__WIN32__) && !defined(_WIN32) && !defined(_WIN32_) && !defined(USE_SELECT)
-struct erl_drv_event_data {
-    short events;
-    short revents;
-};
-#endif
-typedef struct erl_drv_event_data *ErlDrvEventData; /* Event data */
-
 typedef struct {
     unsigned long megasecs;
     unsigned long secs;
@@ -270,10 +262,7 @@ typedef struct erl_drv_entry {
 			 unsigned int *flags); /* Works mostly like 'control',
 						  a synchronous
 						  call into the driver. */
-    void (*event)(ErlDrvData drv_data, ErlDrvEvent event,
-		  ErlDrvEventData event_data);
-                                /* Called when an event selected by 
-				   driver_event() has occurred */
+    void (*unused_event_callback)(void);
     int extended_marker;	/* ERL_DRV_EXTENDED_MARKER */
     int major_version;		/* ERL_DRV_EXTENDED_MAJOR_VERSION */
     int minor_version;		/* ERL_DRV_EXTENDED_MINOR_VERSION */
@@ -340,8 +329,6 @@ EXTERN void erl_drv_busy_msgq_limits(ErlDrvPort port,
 				     ErlDrvSizeT *high);
 
 EXTERN int driver_select(ErlDrvPort port, ErlDrvEvent event, int mode, int on);
-EXTERN int driver_event(ErlDrvPort port, ErlDrvEvent event, 
-			ErlDrvEventData event_data);
 
 EXTERN int driver_output(ErlDrvPort port, char *buf, ErlDrvSizeT len);
 EXTERN int driver_output2(ErlDrvPort port, char *hbuf, ErlDrvSizeT hlen,
diff --git a/erts/emulator/beam/erl_drv_thread.c b/erts/emulator/beam/erl_drv_thread.c
index 742c428f2a..71d4534ef9 100644
--- a/erts/emulator/beam/erl_drv_thread.c
+++ b/erts/emulator/beam/erl_drv_thread.c
@@ -50,7 +50,6 @@ fatal_error(int err, char *func)
 #define ERL_DRV_TSD_EXTRA 10
 #define ERL_DRV_INVALID_TSD_KEY INT_MAX
 
-#ifdef USE_THREADS
 
 struct ErlDrvMutex_ {
     ethr_mutex mtx;
@@ -85,10 +84,6 @@ struct ErlDrvTid_ {
 
 static ethr_tsd_key tid_key;
 
-#else /* USE_THREADS */
-static Uint tsd_len;
-static void **tsd;
-#endif
 
 static ErlDrvTSDKey next_tsd_key;
 static ErlDrvTSDKey max_used_tsd_key;
@@ -97,7 +92,6 @@ static char **used_tsd_keys;
 static erts_mtx_t tsd_mtx;
 static char *no_name;
 
-#ifdef USE_THREADS
 
 static void
 thread_exit_handler(void)
@@ -122,21 +116,15 @@ erl_drv_thread_wrapper(void *vdtid)
     return (*dtid->func)(dtid->arg);
 }
 
-#endif
 
 void erl_drv_thr_init(void)
 {
     int i;
-#ifdef USE_THREADS
     int res = ethr_tsd_key_create(&tid_key,"erts_tid_key");
     if (res == 0)
 	res = ethr_install_exit_handler(thread_exit_handler);
     if (res != 0)
 	fatal_error(res, "erl_drv_thr_init()");
-#else
-    tsd_len = 0;
-    tsd = NULL;
-#endif
 
     no_name = "unknown";
     next_tsd_key = 0;
@@ -153,13 +141,12 @@ void erl_drv_thr_init(void)
 /*
  * These functions implement the driver thread interface in erl_driver.h.
  * NOTE: Only use this interface from drivers. From within the emulator use
- * either the erl_threads.h, the erl_smp.h or the ethread.h interface.
+ * either the erl_threads.h or the ethread.h interface.
  */
 
 ErlDrvMutex *
 erl_drv_mutex_create(char *name)
 {
-#ifdef USE_THREADS
     ErlDrvMutex *dmtx = erts_alloc_fnf(ERTS_ALC_T_DRV_MTX,
 				       (sizeof(ErlDrvMutex)
 					+ (name ? sys_strlen(name) + 1 : 0)));
@@ -182,15 +169,11 @@ erl_drv_mutex_create(char *name)
 #endif
     }
     return dmtx;
-#else
-    return (ErlDrvMutex *) NULL;
-#endif
 }
 
 void
 erl_drv_mutex_destroy(ErlDrvMutex *dmtx)
 {
-#ifdef USE_THREADS
     int res;
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_uninstall(&dmtx->lcnt);
@@ -199,24 +182,18 @@ erl_drv_mutex_destroy(ErlDrvMutex *dmtx)
     if (res != 0)
 	fatal_error(res, "erl_drv_mutex_destroy()");
     erts_free(ERTS_ALC_T_DRV_MTX, (void *) dmtx);
-#endif
 }
 
 
 char *
 erl_drv_mutex_name(ErlDrvMutex *dmtx)
 {
-#ifdef USE_THREADS
     return dmtx ? dmtx->name : NULL;
-#else
-    return NULL;
-#endif
 }
 
 int
 erl_drv_mutex_trylock(ErlDrvMutex *dmtx)
 {
-#ifdef USE_THREADS
     int res;
     if (!dmtx)
 	fatal_error(EINVAL, "erl_drv_mutex_trylock()");
@@ -225,22 +202,17 @@ erl_drv_mutex_trylock(ErlDrvMutex *dmtx)
     erts_lcnt_trylock(&dmtx->lcnt, res);
 #endif
     return res;
-#else
-    return 0;
-#endif
 }
 
 void
 erl_drv_mutex_lock(ErlDrvMutex *dmtx)
 {
-#ifdef USE_THREADS
     if (!dmtx)
 	fatal_error(EINVAL, "erl_drv_mutex_lock()");
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_lock(&dmtx->lcnt);
 #endif
     ethr_mutex_lock(&dmtx->mtx);
-#endif
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_lock_post(&dmtx->lcnt);
 #endif
@@ -249,20 +221,17 @@ erl_drv_mutex_lock(ErlDrvMutex *dmtx)
 void
 erl_drv_mutex_unlock(ErlDrvMutex *dmtx)
 {
-#ifdef USE_THREADS
     if (!dmtx)
 	fatal_error(EINVAL, "erl_drv_mutex_unlock()");
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_unlock(&dmtx->lcnt);
 #endif
     ethr_mutex_unlock(&dmtx->mtx);
-#endif
 }
 
 ErlDrvCond *
 erl_drv_cond_create(char *name)
 {
-#ifdef USE_THREADS
     ErlDrvCond *dcnd = erts_alloc_fnf(ERTS_ALC_T_DRV_CND,
 				      (sizeof(ErlDrvCond)
 				       + (name ? sys_strlen(name) + 1 : 0)));
@@ -281,57 +250,43 @@ erl_drv_cond_create(char *name)
 	}
     }
     return dcnd;
-#else
-    return (ErlDrvCond *) NULL;
-#endif
 }
 
 void
 erl_drv_cond_destroy(ErlDrvCond *dcnd)
 {
-#ifdef USE_THREADS
     int res = dcnd ? ethr_cond_destroy(&dcnd->cnd) : EINVAL;
     if (res != 0)
 	fatal_error(res, "erl_drv_cond_destroy()");
     erts_free(ERTS_ALC_T_DRV_CND, (void *) dcnd);
-#endif
 }
 
 char *
 erl_drv_cond_name(ErlDrvCond *dcnd)
 {
-#ifdef USE_THREADS
     return dcnd ? dcnd->name : NULL;
-#else
-    return NULL;
-#endif
 }
 
 void
 erl_drv_cond_signal(ErlDrvCond *dcnd)
 {
-#ifdef USE_THREADS
     if (!dcnd)
 	fatal_error(EINVAL, "erl_drv_cond_signal()");
     ethr_cond_signal(&dcnd->cnd);
-#endif
 }
 
 void
 erl_drv_cond_broadcast(ErlDrvCond *dcnd)
 {
-#ifdef USE_THREADS
     if (!dcnd)
 	fatal_error(EINVAL, "erl_drv_cond_broadcast()");
     ethr_cond_broadcast(&dcnd->cnd);
-#endif
 }
 
 
 void
 erl_drv_cond_wait(ErlDrvCond *dcnd, ErlDrvMutex *dmtx)
 {
-#ifdef USE_THREADS
     if (!dcnd || !dmtx) {
 	fatal_error(EINVAL, "erl_drv_cond_wait()");
     }
@@ -348,13 +303,11 @@ erl_drv_cond_wait(ErlDrvCond *dcnd, ErlDrvMutex *dmtx)
 	    break;
         }
     }
-#endif
 }
 
 ErlDrvRWLock *
 erl_drv_rwlock_create(char *name)
 {
-#ifdef USE_THREADS
     ErlDrvRWLock *drwlck = erts_alloc_fnf(ERTS_ALC_T_DRV_RWLCK,
 					  (sizeof(ErlDrvRWLock)
 					   + (name ? sys_strlen(name) + 1 : 0)));
@@ -375,15 +328,11 @@ erl_drv_rwlock_create(char *name)
 #endif
     }
     return drwlck;
-#else
-    return (ErlDrvRWLock *) NULL;
-#endif
 }
 
 void
 erl_drv_rwlock_destroy(ErlDrvRWLock *drwlck)
 {
-#ifdef USE_THREADS
     int res;
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_uninstall(&drwlck->lcnt);
@@ -392,23 +341,17 @@ erl_drv_rwlock_destroy(ErlDrvRWLock *drwlck)
     if (res != 0)
 	fatal_error(res, "erl_drv_rwlock_destroy()");
     erts_free(ERTS_ALC_T_DRV_RWLCK, (void *) drwlck);
-#endif
 }
 
 char *
 erl_drv_rwlock_name(ErlDrvRWLock *drwlck)
 {
-#ifdef USE_THREADS
     return drwlck ? drwlck->name : NULL;
-#else
-    return NULL;
-#endif
 }
 
 int
 erl_drv_rwlock_tryrlock(ErlDrvRWLock *drwlck)
 {
-#ifdef USE_THREADS
     int res;
     if (!drwlck)
 	fatal_error(EINVAL, "erl_drv_rwlock_tryrlock()");
@@ -417,15 +360,11 @@ erl_drv_rwlock_tryrlock(ErlDrvRWLock *drwlck)
     erts_lcnt_trylock_opt(&drwlck->lcnt, res, ERTS_LOCK_OPTIONS_READ);
 #endif
     return res;
-#else
-    return 0;
-#endif
 }
 
 void
 erl_drv_rwlock_rlock(ErlDrvRWLock *drwlck)
 {
-#ifdef USE_THREADS
     if (!drwlck)
 	fatal_error(EINVAL, "erl_drv_rwlock_rlock()");
 #ifdef ERTS_ENABLE_LOCK_COUNT
@@ -435,26 +374,22 @@ erl_drv_rwlock_rlock(ErlDrvRWLock *drwlck)
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_lock_post(&drwlck->lcnt);
 #endif
-#endif
 }
 
 void
 erl_drv_rwlock_runlock(ErlDrvRWLock *drwlck)
 {
-#ifdef USE_THREADS
     if (!drwlck)
 	fatal_error(EINVAL, "erl_drv_rwlock_runlock()");
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_unlock_opt(&drwlck->lcnt, ERTS_LOCK_OPTIONS_READ);
 #endif
     ethr_rwmutex_runlock(&drwlck->rwmtx);
-#endif
 }
 
 int
 erl_drv_rwlock_tryrwlock(ErlDrvRWLock *drwlck)
 {
-#ifdef USE_THREADS
     int res;
     if (!drwlck)
 	fatal_error(EINVAL, "erl_drv_rwlock_tryrwlock()");
@@ -463,15 +398,11 @@ erl_drv_rwlock_tryrwlock(ErlDrvRWLock *drwlck)
     erts_lcnt_trylock_opt(&drwlck->lcnt, res, ERTS_LOCK_OPTIONS_RDWR);
 #endif
     return res;
-#else
-    return 0;
-#endif
 }
 
 void
 erl_drv_rwlock_rwlock(ErlDrvRWLock *drwlck)
 {
-#ifdef USE_THREADS
     if (!drwlck)
 	fatal_error(EINVAL, "erl_drv_rwlock_rwlock()");
 #ifdef ERTS_ENABLE_LOCK_COUNT
@@ -481,20 +412,17 @@ erl_drv_rwlock_rwlock(ErlDrvRWLock *drwlck)
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_lock_post(&drwlck->lcnt);
 #endif
-#endif
 }
 
 void
 erl_drv_rwlock_rwunlock(ErlDrvRWLock *drwlck)
 {
-#ifdef USE_THREADS
     if (!drwlck)
 	fatal_error(EINVAL, "erl_drv_rwlock_rwunlock()");
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_unlock_opt(&drwlck->lcnt, ERTS_LOCK_OPTIONS_RDWR);
 #endif
     ethr_rwmutex_rwunlock(&drwlck->rwmtx);
-#endif
 }
 
 int
@@ -588,20 +516,13 @@ erl_drv_tsd_key_destroy(ErlDrvTSDKey key)
 }
 
 
-#ifdef USE_THREADS
 #define ERL_DRV_TSD__ (dtid->tsd)
 #define ERL_DRV_TSD_LEN__ (dtid->tsd_len)
-#else
-#define ERL_DRV_TSD__ (tsd)
-#define ERL_DRV_TSD_LEN__ (tsd_len)
-#endif
 
 void
 erl_drv_tsd_set(ErlDrvTSDKey key, void *data)
 {
-#ifdef USE_THREADS
     struct ErlDrvTid_ *dtid = (struct ErlDrvTid_ *) erl_drv_thread_self();
-#endif
 
     if (key < 0 || max_used_tsd_key < key || !used_tsd_keys[key])
 	fatal_error(EINVAL, "erl_drv_tsd_set()");
@@ -629,15 +550,11 @@ erl_drv_tsd_set(ErlDrvTSDKey key, void *data)
 void *
 erl_drv_tsd_get(ErlDrvTSDKey key)
 {
-#ifdef USE_THREADS
     struct ErlDrvTid_ *dtid = ethr_tsd_get(tid_key);
-#endif
     if (key < 0 || max_used_tsd_key < key || !used_tsd_keys[key])
 	fatal_error(EINVAL, "erl_drv_tsd_get()");
-#ifdef USE_THREADS
     if (!dtid)
 	return NULL;
-#endif
     if (ERL_DRV_TSD_LEN__ <= key)
 	return NULL;
     return ERL_DRV_TSD__[key];
@@ -672,7 +589,6 @@ erl_drv_thread_create(char *name,
 		      void* arg,
 		      ErlDrvThreadOpts *opts)
 {
-#ifdef USE_THREADS
     int res;
     struct ErlDrvTid_ *dtid;
     ethr_thr_opts ethr_opts = ETHR_THR_OPTS_DEFAULT_INITER;
@@ -714,27 +630,19 @@ erl_drv_thread_create(char *name,
 
     *tid = (ErlDrvTid) dtid;
     return 0;
-#else
-    return ENOTSUP;
-#endif
 }
 
 char *
 erl_drv_thread_name(ErlDrvTid tid)
 {
-#ifdef USE_THREADS
     struct ErlDrvTid_ *dtid = (struct ErlDrvTid_ *) tid;
     return dtid ? dtid->name : NULL;
-#else
-    return NULL;
-#endif
 }
 
 
 ErlDrvTid
 erl_drv_thread_self(void)
 {
-#ifdef USE_THREADS
     struct ErlDrvTid_ *dtid = ethr_tsd_get(tid_key);
     if (!dtid) {
 	int res;
@@ -753,15 +661,11 @@ erl_drv_thread_self(void)
 	    fatal_error(res, "erl_drv_thread_self()");
     }
     return (ErlDrvTid) dtid;
-#else
-    return (ErlDrvTid) NULL;
-#endif
 }
 
 int
 erl_drv_equal_tids(ErlDrvTid tid1, ErlDrvTid tid2)
 {   
-#ifdef USE_THREADS
     int res;
     struct ErlDrvTid_ *dtid1 = (struct ErlDrvTid_ *) tid1;
     struct ErlDrvTid_ *dtid2 = (struct ErlDrvTid_ *) tid2;
@@ -775,28 +679,22 @@ erl_drv_equal_tids(ErlDrvTid tid1, ErlDrvTid tid2)
 	   : !ethr_equal_tids(dtid1->tid, dtid2->tid));
 
     return res;
-#else
-    return 1;
-#endif
 }
 
 void
 erl_drv_thread_exit(void *res)
 {
-#ifdef USE_THREADS
     struct ErlDrvTid_ *dtid = ethr_tsd_get(tid_key);
     if (dtid && dtid->drv_thr) {
 	ethr_thr_exit(res);
 	fatal_error(0, "erl_drv_thread_exit()");
     }
-#endif
     fatal_error(EACCES, "erl_drv_thread_exit()");
 }
 
 int
 erl_drv_thread_join(ErlDrvTid tid, void **respp)
 {
-#ifdef USE_THREADS
     int res;
     struct ErlDrvTid_ *dtid = (struct ErlDrvTid_ *) tid;
 
@@ -809,12 +707,9 @@ erl_drv_thread_join(ErlDrvTid tid, void **respp)
     if (res == 0)
 	erts_free(ERTS_ALC_T_DRV_TID, dtid);
     return res;
-#else
-    return ENOTSUP;
-#endif
 }
 
-#if defined(__DARWIN__) && defined(USE_THREADS) && defined(ERTS_SMP)
+#if defined(__DARWIN__)
 extern int erts_darwin_main_thread_pipe[2];
 extern int erts_darwin_main_thread_result_pipe[2];
 
diff --git a/erts/emulator/beam/erl_fun.c b/erts/emulator/beam/erl_fun.c
index 535f677bb3..9c866250bb 100644
--- a/erts/emulator/beam/erl_fun.c
+++ b/erts/emulator/beam/erl_fun.c
@@ -30,17 +30,16 @@
 
 static Hash erts_fun_table;
 
-#include "erl_smp.h"
 #ifdef HIPE
 # include "hipe_mode_switch.h"
 #endif
 
-static erts_smp_rwmtx_t erts_fun_table_lock;
+static erts_rwmtx_t erts_fun_table_lock;
 
-#define erts_fun_read_lock()	erts_smp_rwmtx_rlock(&erts_fun_table_lock)
-#define erts_fun_read_unlock()	erts_smp_rwmtx_runlock(&erts_fun_table_lock)
-#define erts_fun_write_lock()	erts_smp_rwmtx_rwlock(&erts_fun_table_lock)
-#define erts_fun_write_unlock()	erts_smp_rwmtx_rwunlock(&erts_fun_table_lock)
+#define erts_fun_read_lock()	erts_rwmtx_rlock(&erts_fun_table_lock)
+#define erts_fun_read_unlock()	erts_rwmtx_runlock(&erts_fun_table_lock)
+#define erts_fun_write_lock()	erts_rwmtx_rwlock(&erts_fun_table_lock)
+#define erts_fun_write_unlock()	erts_rwmtx_rwunlock(&erts_fun_table_lock)
 
 static HashValue fun_hash(ErlFunEntry* obj);
 static int fun_cmp(ErlFunEntry* obj1, ErlFunEntry* obj2);
@@ -59,11 +58,11 @@ void
 erts_init_fun_table(void)
 {
     HashFunctions f;
-    erts_smp_rwmtx_opt_t rwmtx_opt = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
-    rwmtx_opt.type = ERTS_SMP_RWMTX_TYPE_FREQUENT_READ;
-    rwmtx_opt.lived = ERTS_SMP_RWMTX_LONG_LIVED;
+    erts_rwmtx_opt_t rwmtx_opt = ERTS_RWMTX_OPT_DEFAULT_INITER;
+    rwmtx_opt.type = ERTS_RWMTX_TYPE_FREQUENT_READ;
+    rwmtx_opt.lived = ERTS_RWMTX_LONG_LIVED;
 
-    erts_smp_rwmtx_init_opt(&erts_fun_table_lock, &rwmtx_opt, "fun_tab", NIL,
+    erts_rwmtx_init_opt(&erts_fun_table_lock, &rwmtx_opt, "fun_tab", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
 
     f.hash = (H_FUN) fun_hash;
@@ -114,9 +113,9 @@ erts_put_fun_entry(Eterm mod, int uniq, int index)
     fe = (ErlFunEntry *) hash_put(&erts_fun_table, (void*) &template);
     sys_memset(fe->uniq, 0, sizeof(fe->uniq));
     fe->index = 0;
-    refc = erts_smp_refc_inctest(&fe->refc, 0);
+    refc = erts_refc_inctest(&fe->refc, 0);
     if (refc < 2) /* New or pending delete */
-	erts_smp_refc_inc(&fe->refc, 1);
+	erts_refc_inc(&fe->refc, 1);
     erts_fun_write_unlock();
     return fe;
 }
@@ -138,9 +137,9 @@ erts_put_fun_entry2(Eterm mod, int old_uniq, int old_index,
     sys_memcpy(fe->uniq, uniq, sizeof(fe->uniq));
     fe->index = index;
     fe->arity = arity;
-    refc = erts_smp_refc_inctest(&fe->refc, 0);
+    refc = erts_refc_inctest(&fe->refc, 0);
     if (refc < 2) /* New or pending delete */
-	erts_smp_refc_inc(&fe->refc, 1);
+	erts_refc_inc(&fe->refc, 1);
     erts_fun_write_unlock();
     return fe;
 }
@@ -165,9 +164,9 @@ erts_get_fun_entry(Eterm mod, int uniq, int index)
     erts_fun_read_lock();
     ret = (ErlFunEntry *) hash_get(&erts_fun_table, (void*) &template);
     if (ret) {
-	erts_aint_t refc = erts_smp_refc_inctest(&ret->refc, 1);
+	erts_aint_t refc = erts_refc_inctest(&ret->refc, 1);
 	if (refc < 2) /* Pending delete */
-	    erts_smp_refc_inc(&ret->refc, 1);
+	    erts_refc_inc(&ret->refc, 1);
     }
     erts_fun_read_unlock();
     return ret;
@@ -183,13 +182,11 @@ void
 erts_erase_fun_entry(ErlFunEntry* fe)
 {
     erts_fun_write_lock();
-#ifdef ERTS_SMP
     /*
      * We have to check refc again since someone might have looked up
      * the fun entry and incremented refc after last check.
      */
-    if (erts_smp_refc_dectest(&fe->refc, -1) <= 0)
-#endif
+    if (erts_refc_dectest(&fe->refc, -1) <= 0)
     {
 	if (fe->address != unloaded_fun)
 	    erts_exit(ERTS_ERROR_EXIT,
@@ -221,7 +218,7 @@ erts_fun_purge_prepare(BeamInstr* start, BeamInstr* end)
 
 	    if (start <= addr && addr < end) {
 		fe->pend_purge_address = addr;
-		ERTS_SMP_WRITE_MEMORY_BARRIER;
+		ERTS_THR_WRITE_MEMORY_BARRIER;
 		fe->address = unloaded_fun;
 #ifdef HIPE
                 fe->pend_purge_native_address = fe->native_address;
@@ -275,10 +272,10 @@ erts_fun_purge_complete(ErlFunEntry **funs, Uint no)
 #ifdef HIPE
         fe->pend_purge_native_address = NULL;
 #endif
-	if (erts_smp_refc_dectest(&fe->refc, 0) == 0)
+	if (erts_refc_dectest(&fe->refc, 0) == 0)
 	    erts_erase_fun_entry(fe);
     }
-    ERTS_SMP_WRITE_MEMORY_BARRIER;
+    ERTS_THR_WRITE_MEMORY_BARRIER;
 }
 
 void
@@ -307,7 +304,7 @@ erts_dump_fun_entries(fmtfn_t to, void *to_arg)
 #ifdef HIPE
 	    erts_print(to, to_arg, "Native_address: %p\n", fe->native_address);
 #endif
-	    erts_print(to, to_arg, "Refc: %ld\n", erts_smp_refc_read(&fe->refc, 1));
+	    erts_print(to, to_arg, "Refc: %ld\n", erts_refc_read(&fe->refc, 1));
 	    b = b->next;
 	}
     }
@@ -338,7 +335,7 @@ fun_alloc(ErlFunEntry* template)
     obj->old_uniq = template->old_uniq;
     obj->old_index = template->old_index;
     obj->module = template->module;
-    erts_smp_refc_init(&obj->refc, -1);
+    erts_refc_init(&obj->refc, -1);
     obj->address = unloaded_fun;
     obj->pend_purge_address = NULL;
 #ifdef HIPE
diff --git a/erts/emulator/beam/erl_fun.h b/erts/emulator/beam/erl_fun.h
index 289d0d0b28..fb2901d866 100644
--- a/erts/emulator/beam/erl_fun.h
+++ b/erts/emulator/beam/erl_fun.h
@@ -21,7 +21,7 @@
 #ifndef __ERLFUNTABLE_H__
 #define __ERLFUNTABLE_H__
 
-#include "erl_smp.h"
+#include "erl_threads.h"
 
 /*
  * Fun entry.
@@ -42,7 +42,7 @@ typedef struct erl_fun_entry {
 
     Uint arity;			/* The arity of the fun. */
     Eterm module;		/* Tagged atom for module. */
-    erts_smp_refc_t refc;		/* Reference count: One for code + one for each
+    erts_refc_t refc;		/* Reference count: One for code + one for each
 				   fun object in each process. */
     BeamInstr *pend_purge_address; /* address stored during a pending purge */
 #ifdef HIPE
diff --git a/erts/emulator/beam/erl_gc.c b/erts/emulator/beam/erl_gc.c
index 6a87136463..0da4468f9c 100644
--- a/erts/emulator/beam/erl_gc.c
+++ b/erts/emulator/beam/erl_gc.c
@@ -180,15 +180,13 @@ typedef struct {
     Eterm ref;
     Eterm ref_heap[ERTS_REF_THING_SIZE];
     Uint req_sched;
-    erts_smp_atomic32_t refc;
+    erts_atomic32_t refc;
 } ErtsGCInfoReq;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 static struct {
     erts_mtx_t mtx;
     ErtsGCInfo info;
 } dirty_gc;
-#endif
 
 static ERTS_INLINE int
 gc_cost(Uint gc_moved_live_words, Uint resize_moved_words)
@@ -273,11 +271,9 @@ erts_init_gc(void)
       init_gc_info(&esdp->gc_info);
     }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
-    erts_smp_mtx_init(&dirty_gc.mtx, "dirty_gc_info", NIL,
+    erts_mtx_init(&dirty_gc.mtx, "dirty_gc_info", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
     init_gc_info(&dirty_gc.info);
-#endif
 
     init_gcireq_alloc();
 }
@@ -341,7 +337,7 @@ erts_heap_sizes(Process* p)
 
     for (i = num_heap_sizes-1; i >= 0; i--) {
 	n += 2;
-	if (!MY_IS_SSMALL(heap_sizes[i])) {
+	if (!IS_SSMALL(heap_sizes[i])) {
 	    big += BIG_UINT_HEAP_SIZE;
 	}
     }
@@ -356,7 +352,7 @@ erts_heap_sizes(Process* p)
 	Eterm num;
 	Sint sz = heap_sizes[i];
 
-	if (MY_IS_SSMALL(sz)) {
+	if (IS_SSMALL(sz)) {
 	    num = make_small(sz);
 	} else {
 	    num = uint_to_big(sz, bigp);
@@ -481,12 +477,10 @@ delay_garbage_collection(Process *p, ErlHeapFragment *live_hf_end, int need, int
     }
 
     if (need == 0) {
-#ifdef ERTS_DIRTY_SCHEDULERS
         if (p->flags & (F_DIRTY_MAJOR_GC|F_DIRTY_MINOR_GC)) {
             ASSERT(!ERTS_SCHEDULER_IS_DIRTY(erts_proc_sched_data(p)));
             goto force_reschedule;
         }
-#endif
 	return 1;
     }
     /*
@@ -541,9 +535,7 @@ delay_garbage_collection(Process *p, ErlHeapFragment *live_hf_end, int need, int
     p->heap_hfrag = hfrag;
 #endif
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 force_reschedule:
-#endif
 
     /* Make sure that we do a proper GC as soon as possible... */
     p->flags |= F_FORCE_GC;
@@ -616,7 +608,6 @@ young_gen_usage(Process *p)
 	}							\
     } while (0)
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 static ERTS_INLINE void
 check_for_possibly_long_gc(Process *p, Uint ygen_usage)
@@ -640,7 +631,6 @@ check_for_possibly_long_gc(Process *p, Uint ygen_usage)
     }
 }
 
-#endif
 
 /*
  * Garbage collect a process.
@@ -672,24 +662,20 @@ garbage_collect(Process* p, ErlHeapFragment *live_hf_end,
 
     ASSERT(CONTEXT_REDS - ERTS_REDS_LEFT(p, fcalls) >= esdp->virtual_reds);
 
-    state = erts_smp_atomic32_read_nob(&p->state);
+    state = erts_atomic32_read_nob(&p->state);
 
     if ((p->flags & (F_DISABLE_GC|F_DELAY_GC)) || state & ERTS_PSFLG_EXITING) {
-#ifdef ERTS_DIRTY_SCHEDULERS
     delay_gc_before_start:
-#endif
 	return delay_garbage_collection(p, live_hf_end, need, fcalls);
     }
 
     ygen_usage = max_young_gen_usage ? max_young_gen_usage : young_gen_usage(p);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
 	check_for_possibly_long_gc(p, ygen_usage);
 	if (p->flags & (F_DIRTY_MAJOR_GC|F_DIRTY_MINOR_GC))
 	    goto delay_gc_before_start;
     }
-#endif
 
     if (p->abandoned_heap)
 	live_hf_end = ERTS_INVALID_HFRAG_PTR;
@@ -698,7 +684,7 @@ garbage_collect(Process* p, ErlHeapFragment *live_hf_end,
 
     ERTS_MSACC_SET_STATE_CACHED_M(ERTS_MSACC_STATE_GC);
 
-    erts_smp_atomic32_read_bor_nob(&p->state, ERTS_PSFLG_GC);
+    erts_atomic32_read_bor_nob(&p->state, ERTS_PSFLG_GC);
     if (erts_system_monitor_long_gc != 0)
 	start_time = erts_get_monotonic_time(esdp);
 
@@ -731,14 +717,12 @@ garbage_collect(Process* p, ErlHeapFragment *live_hf_end,
             if (IS_TRACED_FL(p, F_TRACE_GC)) {
                 trace_gc(p, am_gc_minor_end, reclaimed_now, THE_NON_VALUE);
             }
-#ifdef ERTS_DIRTY_SCHEDULERS
 	    if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
 		p->flags |= F_NEED_FULLSWEEP;
 		check_for_possibly_long_gc(p, ygen_usage);
 		if (p->flags & F_DIRTY_MAJOR_GC)
 		    goto delay_gc_after_start;
 	    }
-#endif
             goto do_major_collection;
         }
         if (ERTS_SCHEDULER_IS_DIRTY(esdp))
@@ -779,17 +763,15 @@ do_major_collection:
         ErtsProcLocks locks = ERTS_PROC_LOCKS_ALL;
         int res;
 
-        erts_smp_proc_lock(p, ERTS_PROC_LOCKS_ALL_MINOR);
+        erts_proc_lock(p, ERTS_PROC_LOCKS_ALL_MINOR);
         erts_send_exit_signal(p, p->common.id, p, &locks,
                               am_kill, NIL, NULL, 0);
-        erts_smp_proc_unlock(p, locks & ERTS_PROC_LOCKS_ALL_MINOR);
+        erts_proc_unlock(p, locks & ERTS_PROC_LOCKS_ALL_MINOR);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     delay_gc_after_start:
-#endif
         /* erts_send_exit_signal looks for ERTS_PSFLG_GC, so
            we have to remove it after the signal is sent */
-        erts_smp_atomic32_read_band_nob(&p->state, ~ERTS_PSFLG_GC);
+        erts_atomic32_read_band_nob(&p->state, ~ERTS_PSFLG_GC);
 
         /* We have to make sure that we have space for need on the heap */
         res = delay_garbage_collection(p, live_hf_end, need, fcalls);
@@ -797,7 +779,7 @@ do_major_collection:
         return res;
     }
 
-    erts_smp_atomic32_read_band_nob(&p->state, ~ERTS_PSFLG_GC);
+    erts_atomic32_read_band_nob(&p->state, ~ERTS_PSFLG_GC);
 
     if (IS_TRACED_FL(p, F_TRACE_GC)) {
         trace_gc(p, gc_trace_end_tag, reclaimed_now, THE_NON_VALUE);
@@ -821,7 +803,6 @@ do_major_collection:
 	    monitor_large_heap(p);
     }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (ERTS_SCHEDULER_IS_DIRTY(esdp)) {
 	erts_mtx_lock(&dirty_gc.mtx);
 	dirty_gc.info.garbage_cols++;
@@ -829,7 +810,6 @@ do_major_collection:
 	erts_mtx_unlock(&dirty_gc.mtx);
     }
     else
-#endif
     {
 	esdp->gc_info.garbage_cols++;
 	esdp->gc_info.reclaimed += reclaimed_now;
@@ -907,7 +887,6 @@ garbage_collect_hibernate(Process* p, int check_long_gc)
     if (p->flags & F_DISABLE_GC)
 	ERTS_INTERNAL_ERROR("GC disabled");
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (ERTS_SCHEDULER_IS_DIRTY(erts_proc_sched_data(p)))
         p->flags &= ~(F_DIRTY_GC_HIBERNATE|F_DIRTY_MAJOR_GC|F_DIRTY_MINOR_GC);
     else if (check_long_gc) {
@@ -920,11 +899,10 @@ garbage_collect_hibernate(Process* p, int check_long_gc)
 	}
 	p->flags = flags;
     }
-#endif
     /*
      * Preliminaries.
      */
-    erts_smp_atomic32_read_bor_nob(&p->state, ERTS_PSFLG_GC);
+    erts_atomic32_read_bor_nob(&p->state, ERTS_PSFLG_GC);
     ErtsGcQuickSanityCheck(p);
     ASSERT(p->stop == p->hend);	/* Stack must be empty. */
 
@@ -1015,7 +993,7 @@ garbage_collect_hibernate(Process* p, int check_long_gc)
 
     p->flags |= F_HIBERNATED;
 
-    erts_smp_atomic32_read_band_nob(&p->state, ~ERTS_PSFLG_GC);
+    erts_atomic32_read_band_nob(&p->state, ~ERTS_PSFLG_GC);
 
     reds = gc_cost(actual_size, actual_size);
     return reds;
@@ -1110,7 +1088,6 @@ erts_garbage_collect_literals(Process* p, Eterm* literals,
 
     p->flags |= F_NEED_FULLSWEEP;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (ERTS_SCHEDULER_IS_DIRTY(erts_proc_sched_data(p)))
 	p->flags &= ~F_DIRTY_CLA;
     else {
@@ -1126,7 +1103,6 @@ erts_garbage_collect_literals(Process* p, Eterm* literals,
 	    return 10;
 	}
     }
-#endif
 
     reds = (Sint64) garbage_collect(p, ERTS_INVALID_HFRAG_PTR, 0,
 				    p->arg_reg, p->arity, fcalls,
@@ -1137,7 +1113,7 @@ erts_garbage_collect_literals(Process* p, Eterm* literals,
     /*
      * Set GC state.
      */
-    erts_smp_atomic32_read_bor_nob(&p->state, ERTS_PSFLG_GC);
+    erts_atomic32_read_bor_nob(&p->state, ERTS_PSFLG_GC);
 
     /*
      * Just did a major collection (which has discarded the old heap),
@@ -1287,7 +1263,7 @@ erts_garbage_collect_literals(Process* p, Eterm* literals,
                     ExternalThing *etp;
                     ASSERT(is_external_header(ptr->thing_word));
                     etp = (ExternalThing *) ptr;
-                    erts_smp_refc_inc(&etp->node->refc, 1);
+                    erts_refc_inc(&etp->node->refc, 1);
                     break;
                 }
             }
@@ -1309,7 +1285,7 @@ erts_garbage_collect_literals(Process* p, Eterm* literals,
     /*
      * Restore status.
      */
-    erts_smp_atomic32_read_band_nob(&p->state, ~ERTS_PSFLG_GC);
+    erts_atomic32_read_band_nob(&p->state, ~ERTS_PSFLG_GC);
 
     reds += (Sint64) gc_cost((p->htop - p->heap) + byte_lit_size/sizeof(Uint), 0);
 
@@ -2939,7 +2915,7 @@ sweep_off_heap(Process *p, int fullsweep)
 	    case FUN_SUBTAG:
 		{
 		    ErlFunEntry* fe = ((ErlFunThing*)ptr)->fe;
-		    if (erts_smp_refc_dectest(&fe->refc, 0) == 0) {
+		    if (erts_refc_dectest(&fe->refc, 0) == 0) {
 			erts_erase_fun_entry(fe);
 		    }
 		    break;
@@ -3255,7 +3231,6 @@ reply_gc_info(void *vgcirp)
 
     reclaimed = esdp->gc_info.reclaimed;
     garbage_cols = esdp->gc_info.garbage_cols;
-#ifdef ERTS_DIRTY_SCHEDULERS
     /*
      * Add dirty schedulers info on requesting
      * schedulers info
@@ -3266,7 +3241,6 @@ reply_gc_info(void *vgcirp)
 	garbage_cols += dirty_gc.info.garbage_cols;
 	erts_mtx_unlock(&dirty_gc.mtx);
     }
-#endif
 
     sz = 0;
     hpp = NULL;
@@ -3299,11 +3273,11 @@ reply_gc_info(void *vgcirp)
 	rp_locks &= ~ERTS_PROC_LOCK_MAIN;
  
     if (rp_locks)
-	erts_smp_proc_unlock(rp, rp_locks);
+	erts_proc_unlock(rp, rp_locks);
 
     erts_proc_dec_refc(rp);
 
-    if (erts_smp_atomic32_dec_read_nob(&gcirp->refc) == 0)
+    if (erts_atomic32_dec_read_nob(&gcirp->refc) == 0)
 	gcireq_free(vgcirp);
 }
 
@@ -3355,18 +3329,16 @@ erts_gc_info_request(Process *c_p)
     gcirp->proc = c_p;
     gcirp->ref = STORE_NC(&hp, NULL, ref);
     gcirp->req_sched = esdp->no;
-    erts_smp_atomic32_init_nob(&gcirp->refc,
+    erts_atomic32_init_nob(&gcirp->refc,
 			       (erts_aint32_t) erts_no_schedulers);
 
     erts_proc_add_refc(c_p, (Sint) erts_no_schedulers);
 
-#ifdef ERTS_SMP
     if (erts_no_schedulers > 1)
 	erts_schedule_multi_misc_aux_work(1,
 					  erts_no_schedulers,
 					  reply_gc_info,
 					  (void *) gcirp);
-#endif
 
     reply_gc_info((void *) gcirp);
 
@@ -3653,12 +3625,12 @@ erts_check_off_heap2(Process *p, Eterm *htop)
 	    refc = erts_refc_read(&u.pb->val->intern.refc, 1);
 	    break;
 	case FUN_SUBTAG:
-	    refc = erts_smp_refc_read(&u.fun->fe->refc, 1);
+	    refc = erts_refc_read(&u.fun->fe->refc, 1);
 	    break;
 	case EXTERNAL_PID_SUBTAG:
 	case EXTERNAL_PORT_SUBTAG:
 	case EXTERNAL_REF_SUBTAG:
-	    refc = erts_smp_refc_read(&u.ext->node->refc, 1);
+	    refc = erts_refc_read(&u.ext->node->refc, 1);
 	    break;
 	case REF_SUBTAG:
 	    ASSERT(is_magic_ref_thing(u.hdr));
diff --git a/erts/emulator/beam/erl_hl_timer.c b/erts/emulator/beam/erl_hl_timer.c
index 6e5cc7b801..bda2c9b94d 100644
--- a/erts/emulator/beam/erl_hl_timer.c
+++ b/erts/emulator/beam/erl_hl_timer.c
@@ -96,13 +96,6 @@ typedef enum {
 
 #define ERTS_BIF_TIMER_SHORT_TIME 5000
 
-#ifdef ERTS_SMP
-#  define ERTS_HLT_SMP_MEMBAR_LoadLoad_LoadStore \
-    ETHR_MEMBAR(ETHR_LoadLoad|ETHR_LoadStore)
-#else
-#  define ERTS_HLT_SMP_MEMBAR_LoadLoad_LoadStore
-#endif
-
 /* Bit 0 to 10 contains scheduler id (see mask below) */
 #define ERTS_TMR_ROFLG_HLT		(((Uint32) 1) << 11)
 #define ERTS_TMR_ROFLG_BIF_TMR		(((Uint32) 1) << 12)
@@ -159,7 +152,7 @@ typedef struct {
 
 typedef struct {
     Uint32 roflgs;
-    erts_smp_atomic32_t refc;
+    erts_atomic32_t refc;
     union {
 	void *arg;
 	erts_atomic_t next;
@@ -200,7 +193,7 @@ struct ErtsBifTimer_ {
         ErtsTWTimer twt;
     } type;
     struct {
-        erts_smp_atomic32_t state;
+        erts_atomic32_t state;
 #ifdef ERTS_MAGIC_REF_BIF_TIMERS
         ErtsMagicBinary *mbin;
         ErtsHLTimerList proc_list;
@@ -269,7 +262,6 @@ typedef struct {
     erts_atomic_t last;
 } ErtsHLTCncldTmrQTail;
 
-#ifdef ERTS_SMP
 
 typedef struct {
     /*
@@ -301,7 +293,6 @@ typedef struct {
     } head;
 } ErtsHLTCncldTmrQ;
 
-#endif /* ERTS_SMP */
 
 typedef struct {
     ErtsHLTimer *root;
@@ -309,9 +300,7 @@ typedef struct {
 } ErtsYieldingTimeoutState;
 
 struct ErtsHLTimerService_ {
-#ifdef ERTS_SMP
     ErtsHLTCncldTmrQ canceled_queue;
-#endif
     ErtsHLTimer *time_tree;
 #ifndef ERTS_MAGIC_REF_BIF_TIMERS
     ErtsBifTimer *btm_tree;
@@ -720,9 +709,7 @@ proc_btm_list_foreach_destroy_yielding(ErtsBifTimer **list,
 
 #endif /* !ERTS_MAGIC_REF_BIF_TIMERS */
 
-#ifdef ERTS_SMP
 static void init_canceled_queue(ErtsHLTCncldTmrQ *cq);
-#endif
 
 void
 erts_hl_timer_init(void)
@@ -747,9 +734,7 @@ erts_create_timer_service(void)
     srv->yield = init_yield;
     erts_twheel_init_timer(&srv->service_timer);
 
-#ifdef ERTS_SMP
     init_canceled_queue(&srv->canceled_queue);
-#endif
 
     return srv;
 }
@@ -791,13 +776,13 @@ get_time_left(ErtsSchedulerData *esdp, ErtsMonotonicTime timeout_pos)
 static ERTS_INLINE int
 proc_timeout_common(Process *proc, void *tmr)
 {
-    if (tmr == (void *) erts_smp_atomic_cmpxchg_mb(&proc->common.timer,
+    if (tmr == (void *) erts_atomic_cmpxchg_mb(&proc->common.timer,
 						   ERTS_PTMR_TIMEDOUT,
 						   (erts_aint_t) tmr)) {
 	erts_aint32_t state;
-	erts_smp_proc_lock(proc, ERTS_PROC_LOCKS_MSG_RECEIVE);
-	state = erts_smp_atomic32_read_acqb(&proc->state);
-	erts_smp_proc_unlock(proc, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	erts_proc_lock(proc, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	state = erts_atomic32_read_acqb(&proc->state);
+	erts_proc_unlock(proc, ERTS_PROC_LOCKS_MSG_RECEIVE);
 	if (!(state & (ERTS_PSFLG_ACTIVE|ERTS_PSFLG_EXITING)))
 	    erts_schedule_process(proc, state, 0);
 	return 1;
@@ -808,7 +793,7 @@ proc_timeout_common(Process *proc, void *tmr)
 static ERTS_INLINE int
 port_timeout_common(Port *port, void *tmr)
 {
-    if (tmr == (void *) erts_smp_atomic_cmpxchg_mb(&port->common.timer,
+    if (tmr == (void *) erts_atomic_cmpxchg_mb(&port->common.timer,
 						   ERTS_PTMR_TIMEDOUT,
 						   (erts_aint_t) tmr)) {
 	erts_port_task_schedule(port->common.id,
@@ -821,24 +806,24 @@ port_timeout_common(Port *port, void *tmr)
 
 #ifdef ERTS_MAGIC_REF_BIF_TIMERS
 
-static erts_smp_atomic_t *
+static erts_atomic_t *
 mbin_to_btmref__(ErtsMagicBinary *mbin)
 {
-    return erts_smp_binary_to_magic_indirection((Binary *) mbin);
+    return erts_binary_to_magic_indirection((Binary *) mbin);
 }
 
 static ERTS_INLINE void
 magic_binary_init(ErtsMagicBinary *mbin, ErtsBifTimer *tmr)
 {
-    erts_smp_atomic_t *aptr = mbin_to_btmref__(mbin);
-    erts_smp_atomic_init_nob(aptr, (erts_aint_t) tmr);
+    erts_atomic_t *aptr = mbin_to_btmref__(mbin);
+    erts_atomic_init_nob(aptr, (erts_aint_t) tmr);
 }
 
 static ERTS_INLINE ErtsBifTimer *
 magic_binary_to_btm(ErtsMagicBinary *mbin)
 {
-    erts_smp_atomic_t *aptr = mbin_to_btmref__(mbin);
-    ErtsBifTimer *tmr = (ErtsBifTimer *) erts_smp_atomic_read_nob(aptr);
+    erts_atomic_t *aptr = mbin_to_btmref__(mbin);
+    ErtsBifTimer *tmr = (ErtsBifTimer *) erts_atomic_read_nob(aptr);
     ERTS_HLT_ASSERT(!tmr || tmr->btm.mbin == mbin);
     return tmr;
 }
@@ -884,7 +869,7 @@ init_btm_specifics(ErtsSchedulerData *esdp,
     btm_rbt_insert(&esdp->timer_service->btm_tree, tmr);
 #endif
 
-    erts_smp_atomic32_init_nob(&tmr->btm.state, ERTS_TMR_STATE_ACTIVE);
+    erts_atomic32_init_nob(&tmr->btm.state, ERTS_TMR_STATE_ACTIVE);
     return refc; /* refc from magic binary... */
 }
 
@@ -917,10 +902,10 @@ timer_pre_dec_refc(ErtsTimer *tmr)
 {
 #ifdef ERTS_HLT_DEBUG
     erts_aint_t refc;
-    refc = erts_smp_atomic32_dec_read_nob(&tmr->head.refc);
+    refc = erts_atomic32_dec_read_nob(&tmr->head.refc);
     ERTS_HLT_ASSERT(refc > 0);
 #else
-    erts_smp_atomic32_dec_nob(&tmr->head.refc);
+    erts_atomic32_dec_nob(&tmr->head.refc);
 #endif
 }
 
@@ -969,8 +954,8 @@ schedule_tw_timer_destroy(ErtsTWTimer *tmr)
 static ERTS_INLINE void
 tw_timer_dec_refc(ErtsTWTimer *tmr)
 {
-    if (erts_smp_atomic32_dec_read_relb(&tmr->head.refc) == 0) {
-	ERTS_HLT_SMP_MEMBAR_LoadLoad_LoadStore;
+    if (erts_atomic32_dec_read_relb(&tmr->head.refc) == 0) {
+        ETHR_MEMBAR(ETHR_LoadLoad|ETHR_LoadStore);
 	schedule_tw_timer_destroy(tmr);
     }
 }
@@ -1114,7 +1099,7 @@ create_tw_timer(ErtsSchedulerData *esdp,
 	return NULL;
     }
 
-    erts_smp_atomic32_init_nob(&tmr->head.refc, refc);
+    erts_atomic32_init_nob(&tmr->head.refc, refc);
 
     erts_twheel_set_timer(esdp->timer_wheel,
 			  &tmr->u.tw_tmr,
@@ -1147,7 +1132,7 @@ schedule_hl_timer_destroy(ErtsHLTimer *tmr, Uint32 roflgs)
      * at once...
      */
 
-    ERTS_HLT_ASSERT(erts_smp_atomic32_read_nob(&tmr->head.refc) == 0);
+    ERTS_HLT_ASSERT(erts_atomic32_read_nob(&tmr->head.refc) == 0);
 
     if (roflgs & ERTS_TMR_ROFLG_REG_NAME) {
 	ERTS_HLT_ASSERT(is_atom(tmr->head.receiver.name));
@@ -1179,14 +1164,13 @@ schedule_hl_timer_destroy(ErtsHLTimer *tmr, Uint32 roflgs)
 static ERTS_INLINE void
 hl_timer_dec_refc(ErtsHLTimer *tmr, Uint32 roflgs)
 {
-    if (erts_smp_atomic32_dec_read_relb(&tmr->head.refc) == 0) {
-	ERTS_HLT_SMP_MEMBAR_LoadLoad_LoadStore;
+    if (erts_atomic32_dec_read_relb(&tmr->head.refc) == 0) {
+        ETHR_MEMBAR(ETHR_LoadLoad|ETHR_LoadStore);
 	schedule_hl_timer_destroy(tmr, roflgs);
     }
 }
 
 static void hlt_service_timeout(void *vesdp);
-#ifdef ERTS_SMP
 static void handle_canceled_queue(ErtsSchedulerData *esdp,
 				  ErtsHLTCncldTmrQ *cq,
 				  int use_limit,
@@ -1194,12 +1178,11 @@ static void handle_canceled_queue(ErtsSchedulerData *esdp,
 				  int *need_thr_progress,
 				  ErtsThrPrgrVal *thr_prgr_p,
 				  int *need_more_work);
-#endif
 
 static ERTS_INLINE void
 check_canceled_queue(ErtsSchedulerData *esdp, ErtsHLTimerService *srv)
 {
-#if defined(ERTS_SMP) && ERTS_TMR_CHECK_CANCEL_ON_CREATE
+#if ERTS_TMR_CHECK_CANCEL_ON_CREATE
     ErtsHLTCncldTmrQ *cq = &srv->canceled_queue;
     if (cq->head.first != cq->head.unref_end)
 	handle_canceled_queue(esdp, cq, 1,
@@ -1219,14 +1202,14 @@ bif_timer_ref_destructor(Binary *unused)
 static ERTS_INLINE void
 btm_clear_magic_binary(ErtsBifTimer *tmr)
 {
-    erts_smp_atomic_t *aptr = mbin_to_btmref__(tmr->btm.mbin);
+    erts_atomic_t *aptr = mbin_to_btmref__(tmr->btm.mbin);
     Uint32 roflgs = tmr->type.head.roflgs;
 #ifdef ERTS_HLT_DEBUG
-    erts_aint_t tval = erts_smp_atomic_xchg_nob(aptr,
+    erts_aint_t tval = erts_atomic_xchg_nob(aptr,
                                                 (erts_aint_t) NULL);
     ERTS_HLT_ASSERT(tval == (erts_aint_t) tmr);
 #else
-    erts_smp_atomic_set_nob(aptr, (erts_aint_t) NULL);
+    erts_atomic_set_nob(aptr, (erts_aint_t) NULL);
 #endif
     if (roflgs & ERTS_TMR_ROFLG_HLT)
         hl_timer_dec_refc(&tmr->type.hlt, roflgs);
@@ -1246,7 +1229,7 @@ bif_timer_timeout(ErtsHLTimerService *srv,
     ERTS_HLT_ASSERT(tmr->type.head.roflgs == roflgs);    
     ERTS_HLT_ASSERT(roflgs & ERTS_TMR_ROFLG_BIF_TMR);
 
-    state = erts_smp_atomic32_cmpxchg_acqb(&tmr->btm.state,
+    state = erts_atomic32_cmpxchg_acqb(&tmr->btm.state,
 					   ERTS_TMR_STATE_TIMED_OUT,
 					   ERTS_TMR_STATE_ACTIVE);
 
@@ -1279,7 +1262,7 @@ bif_timer_timeout(ErtsHLTimerService *srv,
             tmr->btm.bp = NULL;
             erts_queue_message(proc, 0, mp, tmr->btm.message,
                                am_clock_service);
-            erts_smp_proc_lock(proc, ERTS_PROC_LOCK_BTM);
+            erts_proc_lock(proc, ERTS_PROC_LOCK_BTM);
             /* If the process is exiting do not disturb the cleanup... */
             if (!ERTS_PROC_IS_EXITING(proc)) {
 #ifdef ERTS_MAGIC_REF_BIF_TIMERS
@@ -1295,7 +1278,7 @@ bif_timer_timeout(ErtsHLTimerService *srv,
                 }
 #endif
             }
-            erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_BTM);
+            erts_proc_unlock(proc, ERTS_PROC_LOCK_BTM);
             if (dec_refc)
                 timer_pre_dec_refc((ErtsTimer *) tmr);
         }
@@ -1432,7 +1415,7 @@ create_hl_timer(ErtsSchedulerData *esdp,
     }
 
     tmr->head.roflgs = roflgs;
-    erts_smp_atomic32_init_nob(&tmr->head.refc, refc);
+    erts_atomic32_init_nob(&tmr->head.refc, refc);
 
     if (!srv->next_timeout
 	|| tmr->timeout < srv->next_timeout->timeout) {
@@ -1664,7 +1647,6 @@ cleanup_sched_local_canceled_timer(ErtsSchedulerData *esdp,
     }
 }
 
-#ifdef ERTS_SMP
 
 static void
 init_canceled_queue(ErtsHLTCncldTmrQ *cq)
@@ -1794,7 +1776,7 @@ cq_check_incoming(ErtsSchedulerData *esdp, ErtsHLTCncldTmrQ *cq)
 	cq->head.next.thr_progress_reached = 1;
 	/* Move unreferenced end pointer forward... */
 
-	ERTS_HLT_SMP_MEMBAR_LoadLoad_LoadStore;
+        ETHR_MEMBAR(ETHR_LoadLoad|ETHR_LoadStore);
 
 	cq->head.unref_end = cq->head.next.unref_end;
 
@@ -1887,31 +1869,24 @@ erts_handle_canceled_timers(void *vesdp,
 			  need_more_work);
 }
 
-#endif /* ERTS_SMP */
 
 static void
 queue_canceled_timer(ErtsSchedulerData *esdp, int rsched_id, ErtsTimer *tmr)
 {
-#ifdef ERTS_SMP
     ErtsHLTCncldTmrQ *cq;
     cq = &ERTS_SCHEDULER_IX(rsched_id-1)->timer_service->canceled_queue;
     if (cq_enqueue(cq, tmr, rsched_id - (int) esdp->no))
 	erts_notify_canceled_timer(esdp, rsched_id);
-#else
-    ERTS_INTERNAL_ERROR("Unexpected enqueue of canceled timer");
-#endif
 }
 
 static void
 continue_cancel_ptimer(ErtsSchedulerData *esdp, ErtsTimer *tmr)
 {
-#ifdef ERTS_SMP
     Uint32 sid = (tmr->head.roflgs & ERTS_TMR_ROFLG_SID_MASK);
 
     if (esdp->no != sid)
 	queue_canceled_timer(esdp, sid, tmr);
     else
-#endif
 	cleanup_sched_local_canceled_timer(esdp, tmr);
 }
 
@@ -1997,7 +1972,7 @@ setup_bif_timer(Process *c_p, int twheel, ErtsMonotonicTime timeout_pos,
 #else
 	    proc_btm_rbt_insert(&proc->bif_timers, tmr);
 #endif
-	    erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_BTM);
+	    erts_proc_unlock(proc, ERTS_PROC_LOCK_BTM);
             tmr->type.head.receiver.proc = proc;
 	}
     }
@@ -2018,7 +1993,7 @@ cancel_bif_timer(ErtsBifTimer *tmr)
     Uint32 roflgs;
     int res;
 
-    state = erts_smp_atomic32_cmpxchg_acqb(&tmr->btm.state,
+    state = erts_atomic32_cmpxchg_acqb(&tmr->btm.state,
 					   ERTS_TMR_STATE_CANCELED,
 					   ERTS_TMR_STATE_ACTIVE);
     if (state != ERTS_TMR_STATE_ACTIVE)
@@ -2040,7 +2015,7 @@ cancel_bif_timer(ErtsBifTimer *tmr)
         proc = tmr->type.head.receiver.proc;
 	ERTS_HLT_ASSERT(!(tmr->type.head.roflgs & ERTS_TMR_ROFLG_REG_NAME));
 
-	erts_smp_proc_lock(proc, ERTS_PROC_LOCK_BTM);
+	erts_proc_lock(proc, ERTS_PROC_LOCK_BTM);
 	/*
 	 * If process is exiting, let it clean up
 	 * the btm tree by itself (it may be in
@@ -2059,7 +2034,7 @@ cancel_bif_timer(ErtsBifTimer *tmr)
 	    res = 1;
 	}
 #endif
-	erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_BTM);
+	erts_proc_unlock(proc, ERTS_PROC_LOCK_BTM);
     }
 
     return res;
@@ -2082,7 +2057,7 @@ access_btm(ErtsBifTimer *tmr, Uint32 sid, ErtsSchedulerData *esdp, int cancel)
                : erts_tweel_read_timeout(&tmr->type.twt.u.tw_tmr));
 
     if (!cancel) {
-        erts_aint32_t state = erts_smp_atomic32_read_acqb(&tmr->btm.state);
+        erts_aint32_t state = erts_atomic32_read_acqb(&tmr->btm.state);
         if (state == ERTS_TMR_STATE_ACTIVE)
             return get_time_left(esdp, timeout);
         return -1;
@@ -2176,7 +2151,7 @@ send_async_info(Process *proc, ErtsProcLocks initial_locks,
 
     locks &= ~initial_locks;
     if (locks)
-        erts_smp_proc_unlock(proc, locks);
+        erts_proc_unlock(proc, locks);
 
     return am_ok;
 }
@@ -2262,7 +2237,7 @@ send_sync_info(Process *proc, ErtsProcLocks initial_locks,
 
     locks &= ~initial_locks;
     if (locks)
-        erts_smp_proc_unlock(proc, locks);
+        erts_proc_unlock(proc, locks);
 
     return am_ok;
 }
@@ -2376,9 +2351,9 @@ try_access_sched_remote_btm(ErtsSchedulerData *esdp,
      * Check if the timer is aimed at current
      * process...
      */
-    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_BTM);
+    erts_proc_lock(c_p, ERTS_PROC_LOCK_BTM);
     tmr = proc_btm_rbt_lookup(c_p->bif_timers, trefn);
-    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_BTM);
+    erts_proc_unlock(c_p, ERTS_PROC_LOCK_BTM);
     if (!tmr)
 	return 0;
 
@@ -2419,7 +2394,7 @@ no_timer_result(Process *c_p, Eterm tref, int cancel, int async, int info)
     erts_queue_message(c_p, locks, mp, msg, am_clock_service);
     locks &= ~ERTS_PROC_LOCK_MAIN;
     if (locks)
-        erts_smp_proc_unlock(c_p, locks);
+        erts_proc_unlock(c_p, locks);
     return am_ok;
 }
 
@@ -2495,7 +2470,7 @@ access_bif_timer(Process *c_p, Eterm tref, int cancel, int async, int info)
 	    req->rrefn[1] = rrefn[1];
 	    req->rrefn[2] = rrefn[2];
 
-	    erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	    erts_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
 
 	    if (ERTS_PROC_PENDING_EXIT(c_p))
 		ERTS_VBUMP_ALL_REDS(c_p);
@@ -2513,10 +2488,10 @@ access_bif_timer(Process *c_p, Eterm tref, int cancel, int async, int info)
 		 *       otherwise, next receive will *not* work
 		 *       as expected!
 		 */
-		ERTS_SMP_MSGQ_MV_INQ2PRIVQ(c_p);
+		ERTS_MSGQ_MV_INQ2PRIVQ(c_p);
 		c_p->msg.save = c_p->msg.last;
 	    }
-	    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	    erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
 
 	    ERTS_BIF_PREP_TRAP1(ret, erts_await_result, c_p, rref);
 	}
@@ -2606,7 +2581,7 @@ exit_cancel_bif_timer(ErtsBifTimer *tmr, void *vesdp)
     erts_aint_t state;
     int is_hlt;
 
-    state = erts_smp_atomic32_cmpxchg_acqb(&tmr->btm.state,
+    state = erts_atomic32_cmpxchg_acqb(&tmr->btm.state,
 					   ERTS_TMR_STATE_CANCELED,
 					   ERTS_TMR_STATE_ACTIVE);
 
@@ -2992,7 +2967,7 @@ set_proc_timer_common(Process *c_p, ErtsSchedulerData *esdp, Sint64 tmo,
                                     ERTS_TMR_PROC, (void *) c_p,
                                     c_p->common.id, THE_NON_VALUE,
                                     NULL, NULL, NULL);
-	erts_smp_atomic_set_relb(&c_p->common.timer, (erts_aint_t) tmr);
+	erts_atomic_set_relb(&c_p->common.timer, (erts_aint_t) tmr);
     }
 }
 
@@ -3003,7 +2978,7 @@ erts_set_proc_timer_term(Process *c_p, Eterm etmo)
     ErtsMonotonicTime tmo, timeout_pos;
     int short_time, tres;
 
-    ERTS_HLT_ASSERT(erts_smp_atomic_read_nob(&c_p->common.timer)
+    ERTS_HLT_ASSERT(erts_atomic_read_nob(&c_p->common.timer)
 		    == ERTS_PTMR_NONE);
 
     tres = parse_timeout_pos(esdp, etmo, &tmo, 0,
@@ -3023,7 +2998,7 @@ erts_set_proc_timer_uword(Process *c_p, UWord tmo)
 {
     ErtsSchedulerData *esdp = erts_proc_sched_data(c_p);
 
-    ERTS_HLT_ASSERT(erts_smp_atomic_read_nob(&c_p->common.timer)
+    ERTS_HLT_ASSERT(erts_atomic_read_nob(&c_p->common.timer)
 		    == ERTS_PTMR_NONE);
 
 #ifndef ARCH_32
@@ -3046,13 +3021,13 @@ void
 erts_cancel_proc_timer(Process *c_p)
 {
     erts_aint_t tval;
-    tval = erts_smp_atomic_xchg_acqb(&c_p->common.timer,
+    tval = erts_atomic_xchg_acqb(&c_p->common.timer,
 				     ERTS_PTMR_NONE);
     c_p->flags &= ~(F_INSLPQUEUE|F_TIMO);
     if (tval == ERTS_PTMR_NONE)
 	return;
     if (tval == ERTS_PTMR_TIMEDOUT) {
-	erts_smp_atomic_set_nob(&c_p->common.timer, ERTS_PTMR_NONE);
+	erts_atomic_set_nob(&c_p->common.timer, ERTS_PTMR_NONE);
 	return;
     }
     continue_cancel_ptimer(erts_proc_sched_data(c_p),
@@ -3067,7 +3042,7 @@ erts_set_port_timer(Port *c_prt, Sint64 tmo)
     ErtsMonotonicTime timeout_pos;
     ErtsCreateTimerFunc create_timer;
 
-    if (erts_smp_atomic_read_nob(&c_prt->common.timer) != ERTS_PTMR_NONE)
+    if (erts_atomic_read_nob(&c_prt->common.timer) != ERTS_PTMR_NONE)
 	erts_cancel_port_timer(c_prt);
 
     check_canceled_queue(esdp, esdp->timer_service);
@@ -3080,14 +3055,14 @@ erts_set_port_timer(Port *c_prt, Sint64 tmo)
     tmr = (void *) create_timer(esdp, timeout_pos, 0, ERTS_TMR_PORT,
                                 (void *) c_prt, c_prt->common.id,
                                 THE_NON_VALUE, NULL, NULL, NULL);
-    erts_smp_atomic_set_relb(&c_prt->common.timer, (erts_aint_t) tmr);
+    erts_atomic_set_relb(&c_prt->common.timer, (erts_aint_t) tmr);
 }
 
 void
 erts_cancel_port_timer(Port *c_prt)
 {
     erts_aint_t tval;
-    tval = erts_smp_atomic_xchg_acqb(&c_prt->common.timer,
+    tval = erts_atomic_xchg_acqb(&c_prt->common.timer,
 				     ERTS_PTMR_NONE);
     if (tval == ERTS_PTMR_NONE)
 	return;
@@ -3095,7 +3070,7 @@ erts_cancel_port_timer(Port *c_prt)
 	while (!erts_port_task_is_scheduled(&c_prt->timeout_task))
 	    erts_thr_yield();
 	erts_port_task_abort(&c_prt->timeout_task);
-	erts_smp_atomic_set_nob(&c_prt->common.timer, ERTS_PTMR_NONE);
+	erts_atomic_set_nob(&c_prt->common.timer, ERTS_PTMR_NONE);
 	return;
     }
     continue_cancel_ptimer(erts_get_scheduler_data(),
@@ -3109,7 +3084,7 @@ erts_read_port_timer(Port *c_prt)
     erts_aint_t itmr;
     ErtsMonotonicTime timeout_pos;
 
-    itmr = erts_smp_atomic_read_acqb(&c_prt->common.timer);
+    itmr = erts_atomic_read_acqb(&c_prt->common.timer);
     if (itmr == ERTS_PTMR_NONE)
 	return (Sint64) -1;
     if (itmr == ERTS_PTMR_TIMEDOUT)
@@ -3246,7 +3221,7 @@ debug_btm_foreach(ErtsBifTimer *tmr, void *vbtmfd)
     if (!(tmr->type.head.roflgs & ERTS_TMR_ROFLG_BIF_TMR))
         return;
 #endif
-    if (erts_smp_atomic32_read_nob(&tmr->btm.state) == ERTS_TMR_STATE_ACTIVE) {
+    if (erts_atomic32_read_nob(&tmr->btm.state) == ERTS_TMR_STATE_ACTIVE) {
 	ErtsBTMForeachDebug *btmfd = (ErtsBTMForeachDebug *) vbtmfd;
         Eterm id = ((tmr->type.head.roflgs & ERTS_TMR_ROFLG_REG_NAME)
                     ? tmr->type.head.receiver.name
@@ -3284,7 +3259,7 @@ erts_debug_bif_timer_foreach(void (*func)(Eterm,
     btmfd.func = func;
     btmfd.arg = arg;
 
-    if (!erts_smp_thr_progress_is_blocking())
+    if (!erts_thr_progress_is_blocking())
 	ERTS_INTERNAL_ERROR("Not blocking thread progress");
 
     for (six = 0; six < erts_no_schedulers; six++) {
@@ -3375,7 +3350,7 @@ erts_debug_callback_timer_foreach(void (*tclbk)(void *),
     dfct.func = func;
     dfct.arg = arg;
 
-    if (!erts_smp_thr_progress_is_blocking())
+    if (!erts_thr_progress_is_blocking())
 	ERTS_INTERNAL_ERROR("Not blocking thread progress");
 
     for (six = 0; six < erts_no_schedulers; six++) {
diff --git a/erts/emulator/beam/erl_hl_timer.h b/erts/emulator/beam/erl_hl_timer.h
index ff31f04cb9..e6f5e8b67d 100644
--- a/erts/emulator/beam/erl_hl_timer.h
+++ b/erts/emulator/beam/erl_hl_timer.h
@@ -36,16 +36,16 @@ typedef struct ErtsHLTimerService_ ErtsHLTimerService;
 #define ERTS_PTMR_TIMEDOUT (ERTS_PTMR_NONE + ((erts_aint_t) 1))
 
 #define ERTS_PTMR_INIT(P) \
-    erts_smp_atomic_init_nob(&(P)->common.timer, ERTS_PTMR_NONE)
+    erts_atomic_init_nob(&(P)->common.timer, ERTS_PTMR_NONE)
 #define ERTS_PTMR_IS_SET(P) \
-    (ERTS_PTMR_NONE != erts_smp_atomic_read_nob(&(P)->common.timer))
+    (ERTS_PTMR_NONE != erts_atomic_read_nob(&(P)->common.timer))
 #define ERTS_PTMR_IS_TIMED_OUT(P) \
-    (ERTS_PTMR_TIMEDOUT == erts_smp_atomic_read_nob(&(P)->common.timer))
+    (ERTS_PTMR_TIMEDOUT == erts_atomic_read_nob(&(P)->common.timer))
 
 #define ERTS_PTMR_CLEAR(P)					\
     do {							\
 	ASSERT(ERTS_PTMR_IS_TIMED_OUT((P)));			\
-	erts_smp_atomic_set_nob(&(P)->common.timer,		\
+	erts_atomic_set_nob(&(P)->common.timer,		\
 				ERTS_PTMR_NONE);		\
     } while (0)
 
@@ -63,13 +63,11 @@ void erts_hl_timer_init(void);
 void erts_start_timer_callback(ErtsMonotonicTime,
 			       void (*)(void *),
 			       void *);
-#ifdef ERTS_SMP
 void
 erts_handle_canceled_timers(void *vesdp,
 			    int *need_thr_progress,
 			    ErtsThrPrgrVal *thr_prgr_p,
 			    int *need_more_work);
-#endif
 
 Uint erts_bif_timer_memory_size(void);
 void erts_print_bif_timer_info(fmtfn_t to, void *to_arg);
diff --git a/erts/emulator/beam/erl_init.c b/erts/emulator/beam/erl_init.c
index 5206d7564f..6cef9bd0e3 100644
--- a/erts/emulator/beam/erl_init.c
+++ b/erts/emulator/beam/erl_init.c
@@ -49,6 +49,7 @@
 #include "erl_bif_unique.h"
 #define ERTS_WANT_TIMER_WHEEL_API
 #include "erl_time.h"
+#include "erl_check_io.h"
 
 #ifdef HIPE
 #include "hipe_mode_switch.h"	/* for hipe_mode_switch_init() */
@@ -69,23 +70,17 @@
  * The variables below (prefixed with etp_) are for erts/etc/unix/etp-commands
  * only. Do not remove even though they aren't used elsewhere in the emulator!
  */
-#ifdef ERTS_SMP
 const int etp_smp_compiled = 1;
-#else
-const int etp_smp_compiled = 0;
-#endif
-#ifdef USE_THREADS
 const int etp_thread_compiled = 1;
-#else
-const int etp_thread_compiled = 0;
-#endif
 const char etp_erts_version[] = ERLANG_VERSION;
 const char etp_otp_release[] = ERLANG_OTP_RELEASE;
 const char etp_compile_date[] = ERLANG_COMPILE_DATE;
 const char etp_arch[] = ERLANG_ARCHITECTURE;
 #ifdef ERTS_ENABLE_KERNEL_POLL
+const int erts_use_kernel_poll = 1;
 const int etp_kernel_poll_support = 1;
 #else
+const int erts_use_kernel_poll = 0;
 const int etp_kernel_poll_support = 0;
 #endif
 #if defined(ARCH_64)
@@ -156,17 +151,10 @@ static void erl_init(int ncpu,
 
 static erts_atomic_t exiting;
 
-#ifdef ERTS_SMP
-erts_smp_atomic32_t erts_writing_erl_crash_dump;
+erts_atomic32_t erts_writing_erl_crash_dump;
 erts_tsd_key_t erts_is_crash_dumping_key;
-#else
-volatile int erts_writing_erl_crash_dump = 0;
-#endif
 int erts_initialized = 0;
 
-#if defined(USE_THREADS) && !defined(ERTS_SMP)
-erts_tid_t erts_main_thread;
-#endif
 
 int erts_use_sender_punish;
 
@@ -185,7 +173,7 @@ int erts_backtrace_depth;	/* How many functions to show in a backtrace
 				 * in error codes.
 				 */
 
-erts_smp_atomic32_t erts_max_gen_gcs;
+erts_atomic32_t erts_max_gen_gcs;
 
 Eterm erts_error_logger_warnings; /* What to map warning logs to, am_error, 
 				     am_info or am_warning, am_error is 
@@ -195,11 +183,9 @@ int erts_compat_rel;
 
 static int no_schedulers;
 static int no_schedulers_online;
-#ifdef ERTS_DIRTY_SCHEDULERS
 static int no_dirty_cpu_schedulers;
 static int no_dirty_cpu_schedulers_online;
 static int no_dirty_io_schedulers;
-#endif
 
 #ifdef DEBUG
 Uint32 verbose;             /* See erl_debug.h for information about verbose */
@@ -220,16 +206,16 @@ int erts_no_line_info = 0;	/* -L: Don't load line information */
  */
 
 ErtsModifiedTimings erts_modified_timings[] = {
-    /* 0 */	{make_small(0), CONTEXT_REDS, INPUT_REDUCTIONS},
-    /* 1 */	{make_small(0), (3*CONTEXT_REDS)/4, 2*INPUT_REDUCTIONS},
-    /* 2 */	{make_small(0), CONTEXT_REDS/2, INPUT_REDUCTIONS/2},
-    /* 3 */	{make_small(0), (7*CONTEXT_REDS)/8, 3*INPUT_REDUCTIONS},
-    /* 4 */	{make_small(0), CONTEXT_REDS/3, 3*INPUT_REDUCTIONS},
-    /* 5 */	{make_small(0), (10*CONTEXT_REDS)/11, INPUT_REDUCTIONS/2},
-    /* 6 */	{make_small(1), CONTEXT_REDS/4, 2*INPUT_REDUCTIONS},
-    /* 7 */	{make_small(1), (5*CONTEXT_REDS)/7, INPUT_REDUCTIONS/3},
-    /* 8 */	{make_small(10), CONTEXT_REDS/5, 3*INPUT_REDUCTIONS},
-    /* 9 */	{make_small(10), (6*CONTEXT_REDS)/7, INPUT_REDUCTIONS/4}
+    /* 0 */	{make_small(0), CONTEXT_REDS},
+    /* 1 */	{make_small(0), (3*CONTEXT_REDS)/4},
+    /* 2 */	{make_small(0), CONTEXT_REDS/2},
+    /* 3 */	{make_small(0), (7*CONTEXT_REDS)/8},
+    /* 4 */	{make_small(0), CONTEXT_REDS/3},
+    /* 5 */	{make_small(0), (10*CONTEXT_REDS)/11},
+    /* 6 */	{make_small(1), CONTEXT_REDS/4},
+    /* 7 */	{make_small(1), (5*CONTEXT_REDS)/7},
+    /* 8 */	{make_small(10), CONTEXT_REDS/5},
+    /* 9 */	{make_small(10), (6*CONTEXT_REDS)/7}
 };
 
 #define ERTS_MODIFIED_TIMING_LEVELS \
@@ -327,12 +313,11 @@ erl_init(int ncpu,
     erts_init_sys_common_misc();
     erts_init_process(ncpu, proc_tab_sz, legacy_proc_tab);
     erts_init_scheduling(no_schedulers,
-			 no_schedulers_online
-#ifdef ERTS_DIRTY_SCHEDULERS
-			 , no_dirty_cpu_schedulers,
+			 no_schedulers_online,
+                         erts_no_poll_threads,
+			 no_dirty_cpu_schedulers,
 			 no_dirty_cpu_schedulers_online,
 			 no_dirty_io_schedulers
-#endif
 			 );
     erts_late_init_time_sup();
     erts_init_cpu_topology(); /* Must be after init_scheduling */
@@ -410,7 +395,7 @@ erl_first_process_otp(char* modname, void* code, unsigned size, int argc, char**
      */
 
     erts_init_empty_process(&parent);
-    erts_smp_proc_lock(&parent, ERTS_PROC_LOCK_MAIN);
+    erts_proc_lock(&parent, ERTS_PROC_LOCK_MAIN);
     hp = HAlloc(&parent, argc*2 + 4);
     args = NIL;
     for (i = argc-1; i >= 0; i--) {
@@ -425,7 +410,7 @@ erl_first_process_otp(char* modname, void* code, unsigned size, int argc, char**
 
     so.flags = erts_default_spo_flags|SPO_SYSTEM_PROC;
     res = erl_create_process(&parent, start_mod, am_start, args, &so);
-    erts_smp_proc_unlock(&parent, ERTS_PROC_LOCK_MAIN);
+    erts_proc_unlock(&parent, ERTS_PROC_LOCK_MAIN);
     erts_cleanup_empty_process(&parent);
     return res;
 }
@@ -450,7 +435,7 @@ erl_system_process_otp(Eterm parent_pid, char* modname, int off_heap_msgq)
     if (off_heap_msgq)
         so.flags |= SPO_OFF_HEAP_MSGQ;
     res = erl_create_process(parent, start_mod, am_start, NIL, &so);
-    erts_smp_proc_unlock(parent, ERTS_PROC_LOCK_MAIN);
+    erts_proc_unlock(parent, ERTS_PROC_LOCK_MAIN);
     return res;
 }
 
@@ -577,9 +562,19 @@ void erts_usage(void)
     erts_fprintf(stderr, "-hmqd  val     set default message queue data flag for processes,\n");
     erts_fprintf(stderr, "               valid values are: off_heap | on_heap\n");
 
+    erts_fprintf(stderr, "-IOp number    set number of pollsets to be used to poll for I/O,\n");
+    erts_fprintf(stderr, "               This value has to be equal or smaller than the\n");
+    erts_fprintf(stderr, "               number of poll threads. If the current platform\n");
+    erts_fprintf(stderr, "               does not support concurrent update of pollsets\n");
+    erts_fprintf(stderr, "               this value is ignored.\n");
+    erts_fprintf(stderr, "-IOt number    set number of threads to be used to poll for I/O\n");
+    erts_fprintf(stderr, "-IOPp number   set number of pollsets as a percentage of the\n");
+    erts_fprintf(stderr, "               number of poll threads.");
+    erts_fprintf(stderr, "-IOPt number   set number of threads to be used to poll for I/O\n");
+    erts_fprintf(stderr, "               as a percentage of the number of schedulers.");
+
     /*    erts_fprintf(stderr, "-i module  set the boot module (default init)\n"); */
 
-    erts_fprintf(stderr, "-K boolean     enable or disable kernel poll\n");
     erts_fprintf(stderr, "-n[s|a|d]      Control behavior of signals to ports\n");
     erts_fprintf(stderr, "               Note that this flag is deprecated!\n");
     erts_fprintf(stderr, "-M<X> <Y>      memory allocator switches,\n");
@@ -624,7 +619,6 @@ void erts_usage(void)
 		 ERTS_SCHED_THREAD_MIN_STACK_SIZE,
 		 ERTS_SCHED_THREAD_MAX_STACK_SIZE,
                  ERTS_DEFAULT_SCHED_STACK_SIZE);
-#ifdef ERTS_DIRTY_SCHEDULERS
     erts_fprintf(stderr, "-sssdcpu size  suggested stack size in kilo words for dirty CPU scheduler\n");
     erts_fprintf(stderr, "               threads, valid range is [%d-%d] (default %d)\n",
 		 ERTS_SCHED_THREAD_MIN_STACK_SIZE,
@@ -635,7 +629,6 @@ void erts_usage(void)
 		 ERTS_SCHED_THREAD_MIN_STACK_SIZE,
 		 ERTS_SCHED_THREAD_MAX_STACK_SIZE,
                  ERTS_DEFAULT_DIO_SCHED_STACK_SIZE);
-#endif
     erts_fprintf(stderr, "-spp Bool      set port parallelism scheduling hint\n");
     erts_fprintf(stderr, "-S n1:n2       set number of schedulers (n1), and number of\n");
     erts_fprintf(stderr, "               schedulers online (n2), maximum for both\n");
@@ -644,7 +637,6 @@ void erts_usage(void)
     erts_fprintf(stderr, "-SP p1:p2      specify schedulers (p1) and schedulers online (p2)\n");
     erts_fprintf(stderr, "               as percentages of logical processors configured and logical\n");
     erts_fprintf(stderr, "               processors available, respectively\n");
-#ifdef ERTS_DIRTY_SCHEDULERS
     erts_fprintf(stderr, "-SDcpu n1:n2   set number of dirty CPU schedulers (n1), and number of\n");
     erts_fprintf(stderr, "               dirty CPU schedulers online (n2), valid range for both\n");
     erts_fprintf(stderr, "               numbers is [1-%d], and n2 must be less than or equal to n1\n",
@@ -654,7 +646,6 @@ void erts_usage(void)
     erts_fprintf(stderr, "               and logical processors available, respectively\n");
     erts_fprintf(stderr, "-SDio n        set number of dirty I/O schedulers, valid range is [0-%d]\n",
 		 ERTS_MAX_NO_OF_DIRTY_IO_SCHEDULERS);
-#endif
     erts_fprintf(stderr, "-t size        set the maximum number of atoms the emulator can handle\n");
     erts_fprintf(stderr, "               valid range is [%d-%d]\n",
 		 MIN_ATOM_TABLE_SIZE, MAX_ATOM_TABLE_SIZE);
@@ -682,7 +673,6 @@ void erts_usage(void)
     erts_exit(1, "");
 }
 
-#ifdef USE_THREADS
 /*
  * allocators for thread lib
  */
@@ -724,7 +714,6 @@ static void ethr_ll_free(void *ptr)
     erts_free(ERTS_ALC_T_ETHR_LL, ptr);
 }
 
-#endif
 
 static int
 early_init(int *argc, char **argv) /*
@@ -742,22 +731,16 @@ early_init(int *argc, char **argv) /*
     int schdlrs_percentage = 100;
     int schdlrs_onln_percentage = 100;
     int max_main_threads;
-#ifdef ERTS_DIRTY_SCHEDULERS
     int dirty_cpu_scheds;
     int dirty_cpu_scheds_online;
     int dirty_cpu_scheds_pctg = 100;
     int dirty_cpu_scheds_onln_pctg = 100;
     int dirty_io_scheds;
-#endif
     int max_reader_groups;
     int reader_groups;
     char envbuf[21]; /* enough for any 64-bit integer */
     size_t envbufsz;
 
-#if defined(USE_THREADS) && !defined(ERTS_SMP)
-    erts_main_thread = erts_thr_self();
-#endif
-
     erts_save_emu_args(*argc, argv);
 
     erts_sched_compact_load = 1;
@@ -781,11 +764,6 @@ early_init(int *argc, char **argv) /*
 				     &ncpu,
 				     &ncpuonln,
 				     &ncpuavail);
-#ifndef ERTS_SMP
-    ncpu = 1;
-    ncpuonln = 1;
-    ncpuavail = 1;
-#endif
 
     ignore_break = 0;
     replace_intr = 0;
@@ -797,18 +775,12 @@ early_init(int *argc, char **argv) /*
 
     erts_sys_pre_init();
     erts_atomic_init_nob(&exiting, 0);
-#ifdef ERTS_SMP
     erts_thr_progress_pre_init();
-#endif
 
-#ifdef ERTS_SMP
-    erts_smp_atomic32_init_nob(&erts_writing_erl_crash_dump, 0L);
+    erts_atomic32_init_nob(&erts_writing_erl_crash_dump, 0L);
     erts_tsd_key_create(&erts_is_crash_dumping_key,"erts_is_crash_dumping_key");
-#else
-    erts_writing_erl_crash_dump = 0;
-#endif
 
-    erts_smp_atomic32_init_nob(&erts_max_gen_gcs,
+    erts_atomic32_init_nob(&erts_max_gen_gcs,
 			       (erts_aint32_t) ((Uint16) -1));
 
     erts_pre_init_process();
@@ -825,11 +797,9 @@ early_init(int *argc, char **argv) /*
     schdlrs = no_schedulers;
     schdlrs_onln = no_schedulers_online;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     dirty_cpu_scheds = no_schedulers;
     dirty_cpu_scheds_online = no_schedulers_online;
     dirty_io_scheds = 10;
-#endif
 
     envbufsz = sizeof(envbuf);
 
@@ -882,6 +852,7 @@ early_init(int *argc, char **argv) /*
 		    }
 		    break;
 		}
+
 		case 'S' :
 		    if (argv[i][2] == 'P') {
 			int ptot, ponln;
@@ -922,7 +893,6 @@ early_init(int *argc, char **argv) /*
                                 ("using %d:%d scheduler percentages\n",
                                  schdlrs_percentage, schdlrs_onln_percentage));
                     }
-#ifdef ERTS_DIRTY_SCHEDULERS
 		    else if (argv[i][2] == 'D') {
 			char *arg;
 			char *type = argv[i]+3;
@@ -1034,7 +1004,6 @@ early_init(int *argc, char **argv) /*
 			    break;
 			}
 		    }
-#endif
 		    else {
 			int tot, onln;
 			char *arg = get_arg(argv[i]+2, argv[i+1], &i);
@@ -1093,7 +1062,6 @@ early_init(int *argc, char **argv) /*
 	    i++;
 	}
 
-#ifdef ERTS_SMP
 	/* apply any scheduler percentages */
 	if (schdlrs_percentage != 100 || schdlrs_onln_percentage != 100) {
 	    schdlrs = schdlrs * schdlrs_percentage / 100;
@@ -1117,12 +1085,6 @@ early_init(int *argc, char **argv) /*
 		erts_usage();
 	    }
 	}
-#else
-	/* Silence gcc warnings */
-	(void)schdlrs_percentage;
-	(void)schdlrs_onln_percentage;
-#endif
-#ifdef ERTS_DIRTY_SCHEDULERS
 	/* apply any dirty scheduler precentages */
 	if (dirty_cpu_scheds_pctg != 100 || dirty_cpu_scheds_onln_pctg != 100) {
 	    dirty_cpu_scheds = dirty_cpu_scheds * dirty_cpu_scheds_pctg / 100;
@@ -1136,33 +1098,25 @@ early_init(int *argc, char **argv) /*
 	    dirty_cpu_scheds_online = schdlrs_onln;
 	if (dirty_cpu_scheds_online < 1)
 	    dirty_cpu_scheds_online = 1;
-#endif
     }
 
-#ifndef USE_THREADS
-    erts_async_max_threads = 0;
-#endif
 
-#ifdef ERTS_SMP
     no_schedulers = schdlrs;
     no_schedulers_online = schdlrs_onln;
 
     erts_no_schedulers = (Uint) no_schedulers;
-#else
-    erts_no_schedulers = 1;
-#endif
-#ifdef ERTS_DIRTY_SCHEDULERS
     erts_no_dirty_cpu_schedulers = no_dirty_cpu_schedulers = dirty_cpu_scheds;
     no_dirty_cpu_schedulers_online = dirty_cpu_scheds_online;
     erts_no_dirty_io_schedulers = no_dirty_io_schedulers = dirty_io_scheds;
-#endif
     erts_early_init_scheduling(no_schedulers);
 
     alloc_opts.ncpu = ncpu;
     erts_alloc_init(argc, argv, &alloc_opts); /* Handles (and removes)
 						 -M flags. */
     /* Require allocators */
-#ifdef ERTS_SMP
+
+    erts_init_check_io(argc, argv);
+
     /*
      * Thread progress management:
      *
@@ -1170,22 +1124,18 @@ early_init(int *argc, char **argv) /*
      * ** Scheduler threads (see erl_process.c)
      * ** Aux thread (see erl_process.c)
      * ** Sys message dispatcher thread (see erl_trace.c)
+     * ** IO Poll threads (see erl_check_io.c)
      *
      * * Unmanaged threads that need to register:
      * ** Async threads (see erl_async.c)
      * ** Dirty scheduler threads
      */
     erts_thr_progress_init(no_schedulers,
-			   no_schedulers+2,
-#ifndef ERTS_DIRTY_SCHEDULERS
-			   erts_async_max_threads
-#else
+			   no_schedulers+2+erts_no_poll_threads,
 			   erts_async_max_threads +
 			   erts_no_dirty_cpu_schedulers +
 			   erts_no_dirty_io_schedulers
-#endif
 			   );
-#endif
     erts_thr_q_init();
     erts_init_utils();
     erts_early_init_cpu_topology(no_schedulers,
@@ -1193,7 +1143,6 @@ early_init(int *argc, char **argv) /*
 				 max_reader_groups,
 				 &reader_groups);
 
-#ifdef USE_THREADS
     {
 	erts_thr_late_init_data_t elid = ERTS_THR_LATE_INIT_DATA_DEF_INITER;
 	elid.mem.std.alloc = ethr_std_alloc;
@@ -1210,7 +1159,6 @@ early_init(int *argc, char **argv) /*
 
 	erts_thr_late_init(&elid);
     }
-#endif
     erts_msacc_early_init();
 
 #ifdef ERTS_ENABLE_LOCK_CHECK
@@ -1237,40 +1185,6 @@ early_init(int *argc, char **argv) /*
     return ncpu;
 }
 
-#ifndef ERTS_SMP
-
-void *erts_scheduler_stack_limit;
-
-
-static void set_main_stack_size(void)
-{
-    char c;
-    UWord stacksize;
-# if HAVE_DECL_GETRLIMIT && HAVE_DECL_SETRLIMIT && HAVE_DECL_RLIMIT_STACK
-    struct rlimit rl;
-    int bytes;
-    stacksize = erts_sched_thread_suggested_stack_size * sizeof(Uint) * 1024;
-    /* Add some extra pages... neede by some systems... */
-    bytes = (int) stacksize + 3*erts_sys_get_page_size();
-    if (getrlimit(RLIMIT_STACK, &rl) != 0 ||
-        (rl.rlim_cur = bytes, setrlimit(RLIMIT_STACK, &rl) != 0)) {
-        erts_fprintf(stderr, "failed to set stack size for scheduler "
-                     "thread to %d bytes\n", bytes);
-        erts_usage();
-    }
-# else
-    if (modified_sched_thread_suggested_stack_size) {
-	erts_fprintf(stderr, "no OS support for dynamic stack size limit\n");
-	erts_usage();
-    }
-    /* Be conservative and hope it is not more than 64 kWords... */
-    stacksize = 64*1024*sizeof(void *);
-# endif
-
-    erts_scheduler_stack_limit = erts_calc_stacklimit(&c, stacksize);
-}
-
-#endif
 
 void
 erl_start(int argc, char **argv)
@@ -1304,7 +1218,7 @@ erl_start(int argc, char **argv)
     envbufsz = sizeof(envbuf);
     if (erts_sys_getenv_raw("ERL_FULLSWEEP_AFTER", envbuf, &envbufsz) == 0) {
 	Uint16 max_gen_gcs = atoi(envbuf);
-	erts_smp_atomic32_set_nob(&erts_max_gen_gcs,
+	erts_atomic32_set_nob(&erts_max_gen_gcs,
 				  (erts_aint32_t) max_gen_gcs);
     }
 
@@ -1319,10 +1233,8 @@ erl_start(int argc, char **argv)
      * a lot of stack.
      */
     erts_sched_thread_suggested_stack_size = ERTS_DEFAULT_SCHED_STACK_SIZE;
-#ifdef ERTS_DIRTY_SCHEDULERS
     erts_dcpu_sched_thread_suggested_stack_size = ERTS_DEFAULT_DCPU_SCHED_STACK_SIZE;
     erts_dio_sched_thread_suggested_stack_size = ERTS_DEFAULT_DIO_SCHED_STACK_SIZE;
-#endif
 
 #ifdef DEBUG
     verbose = DEBUG_DEFAULT;
@@ -1490,12 +1402,8 @@ erl_start(int argc, char **argv)
 #ifdef DEBUG
 		strcat(tmp, ",DEBUG");
 #endif
-#ifdef ERTS_SMP
 		strcat(tmp, ",SMP");
-#endif
-#ifdef USE_THREADS
 		strcat(tmp, ",ASYNC_THREADS");
-#endif
 #ifdef HIPE
 		strcat(tmp, ",HIPE");
 #endif
@@ -1671,16 +1579,6 @@ erl_start(int argc, char **argv)
 	    have_break_handler = 0;
 	  break;
 
-	case 'K':
-	    /* If kernel poll support is present,
-	       erl_sys_args() will remove the K parameter
-	       and value */
-	    get_arg(argv[i]+2, argv[i+1], &i);
-	    erts_fprintf(stderr,
-		       "kernel-poll not supported; \"K\" parameter ignored\n",
-		       arg);
-	    break;
-
 	case 'n':
 	    arg = get_arg(argv[i]+2, argv[i+1], &i);
 	    switch (arg[0]) {
@@ -1850,22 +1748,9 @@ erl_start(int argc, char **argv)
 		    erts_usage();
 		}
 	    }
-	    else if (has_prefix("ecio", sub_param)) {
-		arg = get_arg(sub_param+4, argv[i+1], &i);
-#ifndef __OSE__
-		if (sys_strcmp("true", arg) == 0)
-		    erts_eager_check_io = 1;
-		else
-#endif
-		if (sys_strcmp("false", arg) == 0)
-		    erts_eager_check_io = 0;
-		else {
-		    erts_fprintf(stderr,
-				 "bad schedule eager check I/O value '%s'\n",
-				 arg);
-		    erts_usage();
-		}
-	    }
+            else if (has_prefix("ecio", sub_param)) {
+                /* ignore argument, eager check io no longer used */
+            }
 	    else if (has_prefix("pp", sub_param)) {
 		arg = get_arg(sub_param+2, argv[i+1], &i);
 		if (sys_strcmp(arg, "true") == 0)
@@ -1941,7 +1826,6 @@ erl_start(int argc, char **argv)
 		VERBOSE(DEBUG_SYSTEM,
 			("scheduler wakeup threshold: %s\n", arg));
 	    }
-#ifdef ERTS_DIRTY_SCHEDULERS
 	    else if (has_prefix("ssdcpu", sub_param)) {
 		/* suggested stack size (Kilo Words) for dirty CPU scheduler threads */
 		arg = get_arg(sub_param+6, argv[i+1], &i);
@@ -1976,7 +1860,6 @@ erl_start(int argc, char **argv)
 			("suggested dirty IO scheduler thread stack size %d kilo words\n",
 			 erts_dio_sched_thread_suggested_stack_size));
 	    }
-#endif
 	    else if (has_prefix("ss", sub_param)) {
 		/* suggested stack size (Kilo Words) for scheduler threads */
 		arg = get_arg(sub_param+2, argv[i+1], &i);
@@ -2007,9 +1890,7 @@ erl_start(int argc, char **argv)
 				 arg);
 		    erts_usage();
 		}
-#ifdef ERTS_SMP
 		erts_runq_supervision_interval = val;
-#endif
 	    }
 	    else {
 		erts_fprintf(stderr, "bad scheduling option %s\n", argv[i]);
@@ -2293,12 +2174,10 @@ erl_start(int argc, char **argv)
 
     if (erts_sched_thread_suggested_stack_size < ERTS_SCHED_THREAD_MIN_STACK_SIZE)
         erts_sched_thread_suggested_stack_size = ERTS_SCHED_THREAD_MIN_STACK_SIZE;
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (erts_dcpu_sched_thread_suggested_stack_size < ERTS_SCHED_THREAD_MIN_STACK_SIZE)
         erts_dcpu_sched_thread_suggested_stack_size = ERTS_SCHED_THREAD_MIN_STACK_SIZE;
     if (erts_dio_sched_thread_suggested_stack_size < ERTS_SCHED_THREAD_MIN_STACK_SIZE)
         erts_dio_sched_thread_suggested_stack_size = ERTS_SCHED_THREAD_MIN_STACK_SIZE;
-#endif
 
     erl_init(ncpu,
 	     proc_tab_sz,
@@ -2343,7 +2222,6 @@ erl_start(int argc, char **argv)
 	       && erts_literal_area_collector->common.id == pid);
 	erts_proc_inc_refc(erts_literal_area_collector);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 	pid = erl_system_process_otp(otp_ring0_pid, "erts_dirty_process_code_checker", !0);
 	erts_dirty_process_code_checker
 	    = (Process *) erts_ptab_pix2intptr_ddrb(&erts_proc,
@@ -2351,11 +2229,9 @@ erl_start(int argc, char **argv)
 	ASSERT(erts_dirty_process_code_checker
 	       && erts_dirty_process_code_checker->common.id == pid);
 	erts_proc_inc_refc(erts_dirty_process_code_checker);
-#endif
 
     }
 
-#ifdef ERTS_SMP
     erts_start_schedulers();
 
 #ifdef ERTS_ENABLE_LOCK_COUNT
@@ -2364,31 +2240,9 @@ erl_start(int argc, char **argv)
 
     /* Let system specific code decide what to do with the main thread... */
     erts_sys_main_thread(); /* May or may not return! */
-#else
-    {
-	ErtsSchedulerData *esdp = erts_get_scheduler_data();
-        erts_msacc_init_thread("scheduler", 1, 1);
-	erts_thr_set_main_status(1, 1);
-#if ERTS_USE_ASYNC_READY_Q
-	esdp->aux_work_data.async_ready.queue
-	    = erts_get_async_ready_queue(1);
-#endif
-	set_main_stack_size();
-	erts_sched_init_time_sup(esdp);
-        erts_ets_sched_spec_data_init(esdp);
-        erts_aux_work_timeout_late_init(esdp);
-
-#ifdef ERTS_ENABLE_LOCK_COUNT
-        erts_lcnt_post_startup();
-#endif
-
-	process_main(esdp->x_reg_array, esdp->f_reg_array);
-    }
-#endif
 }
 
 
-#ifdef USE_THREADS
 
 __decl_noreturn void erts_thr_fatal_error(int err, char *what)
 {
@@ -2402,7 +2256,6 @@ __decl_noreturn void erts_thr_fatal_error(int err, char *what)
     abort();
 }
 
-#endif
 
 static void
 system_cleanup(int flush_async)
@@ -2415,7 +2268,6 @@ system_cleanup(int flush_async)
 	 * Another thread is currently exiting the system;
 	 * wait for it to do its job.
 	 */
-#ifdef ERTS_SMP
 	if (erts_thr_progress_is_managed_thread()) {
 	    /*
 	     * The exiting thread might be waiting for
@@ -2424,7 +2276,6 @@ system_cleanup(int flush_async)
 	    erts_thr_progress_active(NULL, 0);
 	    erts_thr_progress_prepare_wait(NULL);
 	}
-#endif
 	/* Wait forever... */
 	while (1)
 	    erts_milli_sleep(10000000);
@@ -2439,17 +2290,12 @@ system_cleanup(int flush_async)
 
     if (!flush_async
 	|| !erts_initialized
-#if defined(USE_THREADS) && !defined(ERTS_SMP)
-	|| !erts_equal_tids(erts_main_thread, erts_thr_self())
-#endif
 	)
 	return;
 
-#ifdef ERTS_SMP
 #ifdef ERTS_ENABLE_LOCK_CHECK
     erts_lc_check_exact(NULL, 0);
 #endif
-#endif
 
     erts_exit_flush_async();
 }
diff --git a/erts/emulator/beam/erl_io_queue.c b/erts/emulator/beam/erl_io_queue.c
index 190ba6bbb9..40d69ea6b0 100644
--- a/erts/emulator/beam/erl_io_queue.c
+++ b/erts/emulator/beam/erl_io_queue.c
@@ -658,7 +658,7 @@ io_list_vec_count(Eterm obj, Uint *v_size,
 int
 erts_ioq_iolist_vec_len(Eterm obj, int* vsize, Uint* csize,
                         Uint* pvsize, Uint* pcsize,
-                        Uint* total_size, Uint blimit)
+                        size_t* total_size, Uint blimit)
 {
     DECLARE_ESTACK(s);
     Eterm* objp;
@@ -669,7 +669,7 @@ erts_ioq_iolist_vec_len(Eterm obj, int* vsize, Uint* csize,
     Uint p_v_size = 0;
     Uint p_c_size = 0;
     Uint p_in_clist = 0;
-    Uint total;
+    size_t total;
 
     goto L_jump_start;  /* avoid a push */
 
diff --git a/erts/emulator/beam/erl_io_queue.h b/erts/emulator/beam/erl_io_queue.h
index 51abe99510..7d0fe6751c 100644
--- a/erts/emulator/beam/erl_io_queue.h
+++ b/erts/emulator/beam/erl_io_queue.h
@@ -103,7 +103,7 @@ Uint erts_ioq_sizeq(ErtsIOQueue *q);
 
 int erts_ioq_iolist_vec_len(Eterm obj, int* vsize, Uint* csize,
                             Uint* pvsize, Uint* pcsize,
-                            Uint* total_size, Uint blimit);
+                            size_t* total_size, Uint blimit);
 int erts_ioq_iolist_to_vec(Eterm obj, SysIOVec* iov,
                            ErtsIOQBinary** binv, ErtsIOQBinary* cbin,
                            Uint bin_limit, int driver_binary);
@@ -111,7 +111,7 @@ int erts_ioq_iolist_to_vec(Eterm obj, SysIOVec* iov,
 ERTS_GLB_INLINE
 int erts_ioq_iodata_vec_len(Eterm obj, int* vsize, Uint* csize,
                             Uint* pvsize, Uint* pcsize,
-                            Uint* total_size, Uint blimit);
+                            size_t* total_size, Uint blimit);
 ERTS_GLB_INLINE
 int erts_ioq_iodata_to_vec(Eterm obj, SysIOVec* iov,
                            ErtsIOQBinary** binv, ErtsIOQBinary* cbin,
@@ -123,7 +123,7 @@ int erts_ioq_iodata_to_vec(Eterm obj, SysIOVec* iov,
 ERTS_GLB_INLINE
 int erts_ioq_iodata_vec_len(Eterm obj, int* vsize, Uint* csize,
                             Uint* pvsize, Uint* pcsize,
-                            Uint* total_size, Uint blimit) {
+                            size_t* total_size, Uint blimit) {
   if (is_binary(obj)) {
     /* We optimize for when we get a procbin without a bit-offset
      * that fits in one iov slot
diff --git a/erts/emulator/beam/erl_lock_check.c b/erts/emulator/beam/erl_lock_check.c
index 189c88ac4a..64950fc252 100644
--- a/erts/emulator/beam/erl_lock_check.c
+++ b/erts/emulator/beam/erl_lock_check.c
@@ -75,12 +75,9 @@ static erts_lc_lock_order_t erts_lock_order[] = {
      *						 if only one lock use
      *						 the lock name)"
      */
-#ifdef ERTS_SMP
     {	"driver_lock",				"driver_name"		},
     {	"port_lock",				"port_id"		},
-#endif
     {	"port_data_lock",			"address"		},
-#ifdef ERTS_SMP
     {	"bif_timers",				NULL			},
     {	"reg_tab",				NULL			},
     {	"proc_main",				"pid"			},
@@ -89,9 +86,11 @@ static erts_lc_lock_order_t erts_lock_order[] = {
     {	"hipe_mfait_lock",			NULL			},
 #endif
     {	"nodes_monitors",			NULL			},
-#ifdef ERTS_SMP
+    {	"meta_name_tab",	         	"address"		},
+    {	"db_tab",				"address"		},
+    {	"db_tab_fix",				"address"		},
+    {	"db_hash_slot",				"address"		},
     {	"resource_monitors",			"address"	        },
-#endif
     {   "driver_list",                          NULL                    },
     {	"proc_link",				"pid"			},
     {	"proc_msgq",				"pid"			},
@@ -100,12 +99,8 @@ static erts_lc_lock_order_t erts_lock_order[] = {
     {	"dist_entry_links",			"address"		},
     {   "code_write_permission",                NULL                    },
     {	"purge_state",		      		NULL			},
-    {	"meta_name_tab",	         	"address"		},
-    {	"db_tab",				"address"		},
     {	"proc_status",				"pid"			},
     {	"proc_trace",				"pid"			},
-    {	"db_tab_fix",				"address"		},
-    {	"db_hash_slot",				"address"		},
     {	"node_table",				NULL			},
     {	"dist_table",				NULL			},
     {	"sys_tracers",				NULL			},
@@ -114,22 +109,17 @@ static erts_lc_lock_order_t erts_lock_order[] = {
     {	"fun_tab",				NULL			},
     {	"environ",				NULL			},
     {	"release_literal_areas",		NULL			},
-#endif
-    {	"efile_drv",				"address"		},
     {	"drv_ev_state_grow",			NULL,   		},
     {	"drv_ev_state",				"address"		},
     {	"safe_hash",				"address"		},
-    {   "pollset_rm_list",                      NULL                    },
     {   "removed_fd_pre_alloc_lock",            "address"               },
     {   "state_prealloc",                       NULL                    },
     {	"schdlr_sspnd",				NULL			},
     {	"migration_info_update",		NULL			},
     {	"run_queue",				"address"		},
-#ifdef ERTS_DIRTY_SCHEDULERS
     {   "dirty_run_queue_sleep_list",		"address"		},
     {	"dirty_gc_info",			NULL			},
     {	"dirty_break_point_index",		NULL			},
-#endif
     {	"process_table",			NULL			},
     {	"cpu_info",				NULL			},
     {	"pollset",				"address"		},
@@ -144,7 +134,6 @@ static erts_lc_lock_order_t erts_lock_order[] = {
     {	"async_enq_mtx",			NULL			},
     {   "msacc_list_mutex",                     NULL                    },
     {   "msacc_unmanaged_mutex",                NULL                    },
-#ifdef ERTS_SMP
     {	"atom_tab",				NULL			},
     {	"misc_op_list_pre_alloc_lock",		"address"		},
     {	"message_pre_alloc_lock",		"address"		},
@@ -155,17 +144,13 @@ static erts_lc_lock_order_t erts_lock_order[] = {
     {	"sys_msg_q", 				NULL			},
     {	"tracer_mtx", 				NULL			},
     {   "port_table",                           NULL                    },
-#endif
     {	"magic_ref_table",			"address"		},
     {	"mtrace_op",				NULL			},
     {	"instr_x",				NULL			},
     {	"instr",				NULL			},
-#ifdef ERTS_SMP
     {	"pollsets_lock",			NULL			},
-#endif
     {	"alcu_allocator",			"index"			},
     {	"mseg",					NULL			},
-#ifdef ERTS_SMP
     {	"port_task_pre_alloc_lock",		"address"		},
     {	"proclist_pre_alloc_lock",		"address"		},
     {	"xports_list_pre_alloc_lock",		"address"		},
@@ -178,20 +163,14 @@ static erts_lc_lock_order_t erts_lock_order[] = {
     {	"pix_lock",				"address"		},
     {	"run_queues_lists",			NULL			},
     {	"sched_stat",				NULL			},
-#endif
     {	"async_init_mtx",			NULL			},
 #ifdef __WIN32__
 #ifdef DEBUG
     {   "save_ops_lock",                        NULL                    },
 #endif
 #endif
-#ifdef	USE_VM_PROBES
-    {   "efile_drv dtrace mutex",               NULL                    },
-#endif
     {	"mtrace_buf",				NULL			},
-#ifdef ERTS_SMP
     {	"os_monotonic_time",			NULL			},
-#endif
     {	"erts_alloc_hard_debug",		NULL			},
     {	"hard_dbg_mseg",		        NULL	                },
     {	"erts_mmap",				NULL			}
diff --git a/erts/emulator/beam/erl_lock_check.h b/erts/emulator/beam/erl_lock_check.h
index 8c754a8dfa..5c2c38e8f2 100644
--- a/erts/emulator/beam/erl_lock_check.h
+++ b/erts/emulator/beam/erl_lock_check.h
@@ -96,13 +96,7 @@ int erts_lc_is_emu_thr(void);
 
 #define ERTS_LC_ASSERT(A) \
     ((void) (((A) || ERTS_SOMEONE_IS_CRASH_DUMPING) ? 1 : erts_lc_assert_failed(__FILE__, __LINE__, #A)))
-#ifdef ERTS_SMP
-#define ERTS_SMP_LC_ASSERT(A) ERTS_LC_ASSERT(A)
-#else
-#define ERTS_SMP_LC_ASSERT(A) ((void) 1)
-#endif
 #else /* #ifdef ERTS_ENABLE_LOCK_CHECK */
-#define ERTS_SMP_LC_ASSERT(A) ((void) 1)
 #define ERTS_LC_ASSERT(A) ((void) 1)
 #endif /* #ifdef ERTS_ENABLE_LOCK_CHECK */
 
diff --git a/erts/emulator/beam/erl_lock_count.c b/erts/emulator/beam/erl_lock_count.c
index d2e8f47d59..1ae6076b12 100644
--- a/erts/emulator/beam/erl_lock_count.c
+++ b/erts/emulator/beam/erl_lock_count.c
@@ -554,16 +554,6 @@ erts_lock_flags_t erts_lcnt_get_category_mask() {
     return lcnt_category_mask__;
 }
 
-#ifdef ERTS_ENABLE_KERNEL_POLL
-/* erl_poll/erl_check_io only exports one of these variants at a time, and we
- * may need to use either one depending on emulator startup flags. */
-void erts_lcnt_update_pollset_locks_nkp(int);
-void erts_lcnt_update_pollset_locks_kp(int);
-
-void erts_lcnt_update_cio_locks_nkp(int);
-void erts_lcnt_update_cio_locks_kp(int);
-#endif
-
 void erts_lcnt_set_category_mask(erts_lock_flags_t mask) {
     erts_lock_flags_t changed_categories;
 
@@ -590,19 +580,7 @@ void erts_lcnt_set_category_mask(erts_lock_flags_t mask) {
     }
 
     if(changed_categories & ERTS_LOCK_FLAGS_CATEGORY_IO) {
-#ifdef ERTS_ENABLE_KERNEL_POLL
-        if(erts_use_kernel_poll) {
-            erts_lcnt_update_pollset_locks_kp(mask & ERTS_LOCK_FLAGS_CATEGORY_IO);
-            erts_lcnt_update_cio_locks_kp(mask & ERTS_LOCK_FLAGS_CATEGORY_IO);
-        } else {
-            erts_lcnt_update_pollset_locks_nkp(mask & ERTS_LOCK_FLAGS_CATEGORY_IO);
-            erts_lcnt_update_cio_locks_nkp(mask & ERTS_LOCK_FLAGS_CATEGORY_IO);
-        }
-#else
-        erts_lcnt_update_pollset_locks(mask & ERTS_LOCK_FLAGS_CATEGORY_IO);
         erts_lcnt_update_cio_locks(mask & ERTS_LOCK_FLAGS_CATEGORY_IO);
-#endif
-
         erts_lcnt_update_driver_locks(mask & ERTS_LOCK_FLAGS_CATEGORY_IO);
         erts_lcnt_update_port_locks(mask & ERTS_LOCK_FLAGS_CATEGORY_IO);
     }
diff --git a/erts/emulator/beam/erl_map.c b/erts/emulator/beam/erl_map.c
index f0c54e05f7..8047a9567f 100644
--- a/erts/emulator/beam/erl_map.c
+++ b/erts/emulator/beam/erl_map.c
@@ -91,7 +91,6 @@ static BIF_RETTYPE hashmap_merge(Process *p, Eterm nodeA, Eterm nodeB, int swap_
 static Export hashmap_merge_trap_export;
 static BIF_RETTYPE maps_merge_trap_1(BIF_ALIST_1);
 static Uint hashmap_subtree_size(Eterm node);
-static Eterm hashmap_to_list(Process *p, Eterm map, Sint n);
 static Eterm hashmap_keys(Process *p, Eterm map);
 static Eterm hashmap_values(Process *p, Eterm map);
 static Eterm hashmap_delete(Process *p, Uint32 hx, Eterm key, Eterm node, Eterm *value);
@@ -139,80 +138,6 @@ BIF_RETTYPE map_size_1(BIF_ALIST_1) {
     BIF_ERROR(BIF_P, BADMAP);
 }
 
-/* maps:to_list/1 */
-
-BIF_RETTYPE maps_to_list_1(BIF_ALIST_1) {
-    if (is_flatmap(BIF_ARG_1)) {
-	Uint n;
-	Eterm* hp;
-	Eterm *ks,*vs, res, tup;
-	flatmap_t *mp = (flatmap_t*)flatmap_val(BIF_ARG_1);
-
-	ks  = flatmap_get_keys(mp);
-	vs  = flatmap_get_values(mp);
-	n   = flatmap_get_size(mp);
-	hp  = HAlloc(BIF_P, (2 + 3) * n);
-	res = NIL;
-
-	while(n--) {
-	    tup = TUPLE2(hp, ks[n], vs[n]); hp += 3;
-	    res = CONS(hp, tup, res); hp += 2;
-	}
-
-	BIF_RET(res);
-    } else if (is_hashmap(BIF_ARG_1)) {
-	return hashmap_to_list(BIF_P, BIF_ARG_1, -1);
-    }
-
-    BIF_P->fvalue = BIF_ARG_1;
-    BIF_ERROR(BIF_P, BADMAP);
-}
-
-/* erts_internal:maps_to_list/2
- *
- * This function should be removed once iterators are in place.
- * Never document it.
- * Never encourage its usage.
- *
- * A negative value in ARG 2 means the entire map.
- */
-
-BIF_RETTYPE erts_internal_maps_to_list_2(BIF_ALIST_2) {
-    Sint m;
-    if (term_to_Sint(BIF_ARG_2, &m)) {
-        if (is_flatmap(BIF_ARG_1)) {
-            Uint n;
-            Eterm* hp;
-            Eterm *ks,*vs, res, tup;
-            flatmap_t *mp = (flatmap_t*)flatmap_val(BIF_ARG_1);
-
-            ks  = flatmap_get_keys(mp);
-            vs  = flatmap_get_values(mp);
-            n   = flatmap_get_size(mp);
-
-            if (m >= 0) {
-                n = m < n ? m : n;
-            }
-
-            hp  = HAlloc(BIF_P, (2 + 3) * n);
-            res = NIL;
-
-            while(n--) {
-                tup = TUPLE2(hp, ks[n], vs[n]); hp += 3;
-                res = CONS(hp, tup, res); hp += 2;
-            }
-
-            BIF_RET(res);
-        } else if (is_hashmap(BIF_ARG_1)) {
-            return hashmap_to_list(BIF_P, BIF_ARG_1, m);
-        }
-        BIF_P->fvalue = BIF_ARG_1;
-        BIF_ERROR(BIF_P, BADMAP);
-    }
-    BIF_ERROR(BIF_P, BADARG);
-}
-
-
 /* maps:find/2
  * return value if key *matches* a key in the map
  */
@@ -1962,45 +1887,31 @@ BIF_RETTYPE maps_values_1(BIF_ALIST_1) {
     BIF_ERROR(BIF_P, BADMAP);
 }
 
-static Eterm hashmap_to_list(Process *p, Eterm node, Sint m) {
-    DECLARE_WSTACK(stack);
-    Eterm *hp, *kv;
-    Eterm tup, res = NIL;
-    Uint n = hashmap_size(node);
-
-    if (m >= 0) {
-        n = m < n ? m : n;
-    }
-
-    hp  = HAlloc(p, n * (2 + 3));
-    hashmap_iterator_init(&stack, node, 0);
-    while (n--) {
-        kv  = hashmap_iterator_next(&stack);
-        ASSERT(kv != NULL);
-	tup = TUPLE2(hp, CAR(kv), CDR(kv));
-	hp += 3;
-	res = CONS(hp, tup, res);
-	hp += 2;
-    }
-    DESTROY_WSTACK(stack);
-    return res;
-}
-
-void hashmap_iterator_init(ErtsWStack* s, Eterm node, int reverse) {
-    Eterm hdr = *hashmap_val(node);
+static ERTS_INLINE
+Uint hashmap_node_size(Eterm hdr, Eterm **nodep)
+{
     Uint sz;
 
     switch(hdr & _HEADER_MAP_SUBTAG_MASK) {
     case HAMT_SUBTAG_HEAD_ARRAY:
 	sz = 16;
+        if (nodep) ++*nodep;
 	break;
     case HAMT_SUBTAG_HEAD_BITMAP:
+        if (nodep) ++*nodep;
     case HAMT_SUBTAG_NODE_BITMAP:
         sz = hashmap_bitcount(MAP_HEADER_VAL(hdr));
+        ASSERT(sz < 17);
 	break;
     default:
 	erts_exit(ERTS_ABORT_EXIT, "bad header");
     }
+    return sz;
+}
+
+void hashmap_iterator_init(ErtsWStack* s, Eterm node, int reverse) {
+    Eterm hdr = *hashmap_val(node);
+    Uint sz = hashmap_node_size(hdr, NULL);
 
     WSTACK_PUSH3((*s), (UWord)THE_NON_VALUE,  /* end marker */
 		 (UWord)(!reverse ? 0 : sz+1),
@@ -2024,20 +1935,7 @@ Eterm* hashmap_iterator_next(ErtsWStack* s) {
 	    ptr = boxed_val(node);
 	    hdr = *ptr;
 	    ASSERT(is_header(hdr));
-	    switch(hdr & _HEADER_MAP_SUBTAG_MASK) {
-	    case HAMT_SUBTAG_HEAD_ARRAY:
-		ptr++;
-		sz = 16;
-		break;
-	    case HAMT_SUBTAG_HEAD_BITMAP:
-		ptr++;
-	    case HAMT_SUBTAG_NODE_BITMAP:
-		sz = hashmap_bitcount(MAP_HEADER_VAL(hdr));
-		ASSERT(sz < 17);
-		break;
-	    default:
-		erts_exit(ERTS_ABORT_EXIT, "bad header");
-	    }
+            sz = hashmap_node_size(hdr, &ptr);
 
 	    idx++;
 
@@ -2074,20 +1972,7 @@ Eterm* hashmap_iterator_prev(ErtsWStack* s) {
 	    ptr = boxed_val(node);
 	    hdr = *ptr;
 	    ASSERT(is_header(hdr));
-	    switch(hdr & _HEADER_MAP_SUBTAG_MASK) {
-	    case HAMT_SUBTAG_HEAD_ARRAY:
-		ptr++;
-		sz = 16;
-		break;
-	    case HAMT_SUBTAG_HEAD_BITMAP:
-		ptr++;
-	    case HAMT_SUBTAG_NODE_BITMAP:
-		sz = hashmap_bitcount(MAP_HEADER_VAL(hdr));
-		ASSERT(sz < 17);
-		break;
-	    default:
-		erts_exit(ERTS_ERROR_EXIT, "bad header");
-	    }
+            sz = hashmap_node_size(hdr, &ptr);
 
             if (idx > sz)
 		idx = sz;
@@ -3061,6 +2946,363 @@ static Eterm hashmap_bld_tuple_uint(Uint **hpp, Uint *szp, Uint n, Uint nums[])
 }
 
 
+/**
+ * In hashmap the Path is a bit pattern that describes
+ * which slot we should traverse in each hashmap node.
+ * Since each hashmap node can only be up to 16 elements
+ * large we use 4 bits per level in the path.
+ *
+ * So a Path with value 0x110 will first get the 0:th
+ * slot in the head node, and then the 1:st slot in the
+ * resulting node and then finally the 1:st slot in the
+ * node beneath. If that slot is not a leaf, then the path
+ * continues down the 0:th slot until it finds a leaf.
+ *
+ * Once the leaf has been found, the return value is created
+ * by traversing the tree using the the stack that was built
+ * when searching for the first leaf to return.
+ *
+ * The index can become a bignum, which complicates the code
+ * a bit. However it should be very rare that this happens
+ * even on a 32bit system as you would need a tree of depth
+ * 7 or more.
+ *
+ * If the number of elements remaining in the map is greater
+ * than how many we want to return, we build a new Path, using
+ * the stack, that points to the next leaf.
+ *
+ * The third argument to this function controls how the data
+ * is returned.
+ *
+ * iterator: The key-value associations are to be used by
+ *           maps:iterator. The return has this format:
+ *             {K1,V1,{K2,V2,none | [Path | Map]}}
+ *           this makes the maps:next function very simple
+ *           and performant.
+ *
+ * list(): The key-value associations are to be used by
+ *         maps:to_list. The return has this format:
+ *             [Path, Map | [{K1,V1},{K2,V2} | BIF_ARG_3]]
+ *                 or if no more associations remain
+ *             [{K1,V1},{K2,V2} | BIF_ARG_3]
+ */
+
+#define PATH_ELEM_SIZE 4
+#define PATH_ELEM_MASK 0xf
+#define PATH_ELEM(PATH) ((PATH) & PATH_ELEM_MASK)
+#define PATH_ELEMS_PER_DIGIT (sizeof(ErtsDigit) * 8 / PATH_ELEM_SIZE)
+
+BIF_RETTYPE erts_internal_map_next_3(BIF_ALIST_3) {
+
+    Eterm path, map;
+    enum { iterator, list } type;
+
+    path = BIF_ARG_1;
+    map  = BIF_ARG_2;
+
+    if (!is_map(map))
+        BIF_ERROR(BIF_P, BADARG);
+
+    if (BIF_ARG_3 == am_iterator) {
+        type = iterator;
+    } else if (is_nil(BIF_ARG_3) || is_list(BIF_ARG_3)) {
+        type = list;
+    } else {
+        BIF_ERROR(BIF_P, BADARG);
+    }
+
+    if (is_flatmap(map)) {
+        Uint n;
+	Eterm *ks,*vs, res, *hp;
+	flatmap_t *mp = (flatmap_t*)flatmap_val(map);
+
+	ks  = flatmap_get_keys(mp);
+	vs  = flatmap_get_values(mp);
+	n   = flatmap_get_size(mp);
+
+        if (!is_small(BIF_ARG_1) || n < unsigned_val(BIF_ARG_1))
+            BIF_ERROR(BIF_P, BADARG);
+
+        if (type == iterator) {
+            hp  = HAlloc(BIF_P, 4 * n);
+            res = am_none;
+
+            while(n--) {
+                res = TUPLE3(hp, ks[n], vs[n], res); hp += 4;
+            }
+        } else {
+            hp  = HAlloc(BIF_P, (2 + 3) * n);
+            res = BIF_ARG_3;
+
+            while(n--) {
+                Eterm tup = TUPLE2(hp, ks[n], vs[n]); hp += 3;
+                res = CONS(hp, tup, res); hp += 2;
+            }
+        }
+
+	BIF_RET(res);
+    } else {
+        Uint curr_path;
+        Uint path_length = 0;
+        Uint *path_rest = NULL;
+        int i, elems, orig_elems;
+        Eterm node = map, res, *path_ptr = NULL, *hp;
+
+        /* A stack WSTACK is used when traversing the hashmap.
+         * It contains: node, idx, sz, ptr
+         *
+         * `node` is not really needed, but it is very nice to
+         * have when debugging.
+         *
+         * `idx` always points to the next un-explored entry in
+         * a node. If there are no more un-explored entries,
+         * `idx` is equal to `sz`.
+         *
+         * `sz` is the number of elements in the node.
+         *
+         * `ptr` is a pointer to where the elements of the node begins.
+         */
+        DECLARE_WSTACK(stack);
+
+        ASSERT(is_hashmap(node));
+
+/* How many elements we return in one call depends on the number of reductions
+ * that the process has left to run. In debug we return fewer elements to test
+ * the Path implementation better.
+ *
+ * Also, when the path is 0 (i.e. for the first call) we limit the number of
+ * elements to MAP_SMALL_MAP_LIMIT in order to not use a huge amount of heap
+ * when only the first X associations in the hashmap was needed.
+ */
+#if defined(DEBUG)
+#define FCALLS_ELEMS(BIF_P) ((BIF_P->fcalls / 4) & 0xF)
+#else
+#define FCALLS_ELEMS(BIF_P) (BIF_P->fcalls / 4)
+#endif
+
+        if (MAX(FCALLS_ELEMS(BIF_P), 1) < hashmap_size(map))
+            elems = MAX(FCALLS_ELEMS(BIF_P), 1);
+        else
+            elems = hashmap_size(map);
+
+#undef FCALLS_ELEMS
+
+        if (is_small(path)) {
+            curr_path = unsigned_val(path);
+
+            if (curr_path == 0 && elems > MAP_SMALL_MAP_LIMIT) {
+                elems = MAP_SMALL_MAP_LIMIT;
+            }
+        } else if (is_big(path)) {
+            Eterm *big = big_val(path);
+            if (bignum_header_is_neg(*big))
+                BIF_ERROR(BIF_P, BADARG);
+            path_length = BIG_ARITY(big) - 1;
+            curr_path = BIG_DIGIT(big,  0);
+            path_rest = BIG_V(big) + 1;
+        } else {
+            BIF_ERROR(BIF_P, BADARG);
+        }
+
+        if (type == iterator) {
+            /* iterator uses the format {K, V, {K, V, {K, V, [Path | Map]}}},
+             * so each element is 4 words large */
+            hp = HAlloc(BIF_P, 4 * elems);
+            res = am_none;
+        } else {
+            /* list used the format [Path, Map, {K,V}, {K,V} | BIF_ARG_3],
+             * so each element is 2+3 words large */
+            hp = HAlloc(BIF_P, (2 + 3) * elems);
+            res = BIF_ARG_3;
+        }
+
+        orig_elems = elems;
+
+        /* First we look for the leaf to start at using the
+           path given. While doing so, we push each map node
+           and the index onto the stack to use later. */
+        for (i = 1; ; i++) {
+            Eterm *ptr = hashmap_val(node),
+                hdr = *ptr++;
+            Uint sz;
+
+            sz = hashmap_node_size(hdr, &ptr);
+
+            if (PATH_ELEM(curr_path) >= sz)
+                goto badarg;
+
+            WSTACK_PUSH4(stack, node, PATH_ELEM(curr_path)+1, sz, (UWord)ptr);
+
+            /* We have found a leaf, return it and the next X elements */
+            if (is_list(ptr[PATH_ELEM(curr_path)])) {
+                Eterm *lst = list_val(ptr[PATH_ELEM(curr_path)]);
+                if (type == iterator) {
+                    res = TUPLE3(hp, CAR(lst), CDR(lst), res); hp += 4;
+                    /* Note where we should patch the Iterator is needed */
+                    path_ptr = hp-1;
+                } else {
+                    Eterm tup = TUPLE2(hp, CAR(lst), CDR(lst)); hp += 3;
+                    res = CONS(hp, tup, res); hp += 2;
+                }
+                elems--;
+                break;
+            }
+
+            node = ptr[PATH_ELEM(curr_path)];
+
+            curr_path >>= PATH_ELEM_SIZE;
+
+            if (i == PATH_ELEMS_PER_DIGIT) {
+                /* Switch to next bignum word if available,
+                   otherwise just follow 0 path */
+                i = 0;
+                if (path_length) {
+                    curr_path = *path_rest;
+                    path_length--;
+                    path_rest++;
+                } else {
+                    curr_path = 0;
+                }
+            }
+        }
+
+        /* We traverse the hashmap and return at most `elems` elements */
+        while(1) {
+            Eterm *ptr = (Eterm*)WSTACK_POP(stack);
+            Uint sz = (Uint)WSTACK_POP(stack);
+            Uint idx = (Uint)WSTACK_POP(stack);
+            Eterm node = (Eterm)WSTACK_POP(stack);
+
+            while (idx < sz && elems != 0 && is_list(ptr[idx])) {
+                Eterm *lst = list_val(ptr[idx]);
+                if (type == iterator) {
+                    res = TUPLE3(hp, CAR(lst), CDR(lst), res); hp += 4;
+                } else {
+                    Eterm tup = TUPLE2(hp, CAR(lst), CDR(lst)); hp += 3;
+                    res = CONS(hp, tup, res); hp += 2;
+                }
+                elems--;
+                idx++;
+            }
+
+            if (elems == 0) {
+                if (idx < sz) {
+                    /* There are more elements in this node to explore */
+                    WSTACK_PUSH4(stack, node, idx+1, sz, (UWord)ptr);
+                } else {
+                    /* pop stack to find the next value */
+                    while (!WSTACK_ISEMPTY(stack)) {
+                        Eterm *ptr = (Eterm*)WSTACK_POP(stack);
+                        Uint sz = (Uint)WSTACK_POP(stack);
+                        Uint idx = (Uint)WSTACK_POP(stack);
+                        Eterm node = (Eterm)WSTACK_POP(stack);
+                        if (idx < sz) {
+                            WSTACK_PUSH4(stack, node, idx+1, sz, (UWord)ptr);
+                            break;
+                        }
+                    }
+                }
+                break;
+            } else {
+                if (idx < sz) {
+                    Eterm hdr;
+                    /* Push next idx in current node */
+                    WSTACK_PUSH4(stack, node, idx+1, sz, (UWord)ptr);
+
+                    /* Push first idx in child node */
+                    node = ptr[idx];
+                    ptr = hashmap_val(ptr[idx]);
+                    hdr = *ptr++;
+                    sz = hashmap_node_size(hdr, &ptr);
+                    WSTACK_PUSH4(stack, node, 0, sz, (UWord)ptr);
+                }
+            }
+
+            /* There are no more element in the hashmap */
+            if (WSTACK_ISEMPTY(stack)) {
+                break;
+            }
+
+        }
+
+        if (!WSTACK_ISEMPTY(stack)) {
+            Uint depth = WSTACK_COUNT(stack) / 4 + 1;
+            /* +1 because we already have the first element in curr_path */
+            Eterm *path_digits = NULL;
+            Uint curr_path = 0;
+
+            /* If the path cannot fit in a small, we allocate a bignum */
+            if (depth >= PATH_ELEMS_PER_DIGIT) {
+                /* We need multiple ErtsDigit's to represent the path */
+                int big_size = BIG_NEED_FOR_BITS(depth * PATH_ELEM_SIZE);
+                hp = HAlloc(BIF_P, big_size);
+                hp[0] = make_pos_bignum_header(big_size - BIG_NEED_SIZE(0));
+                path_digits = hp + big_size - 1;
+            }
+
+
+            /* Pop the stack to create the complete path to the next leaf */
+            while(!WSTACK_ISEMPTY(stack)) {
+                Uint idx;
+
+                (void)WSTACK_POP(stack);
+                (void)WSTACK_POP(stack);
+                idx = (Uint)WSTACK_POP(stack)-1;
+                /* idx - 1 because idx in the stack is pointing to
+                   the next element to fetch. */
+                (void)WSTACK_POP(stack);
+
+                depth--;
+                if (depth % PATH_ELEMS_PER_DIGIT == 0) {
+                    /* Switch to next bignum element */
+                    path_digits[0] = curr_path;
+                    path_digits--;
+                    curr_path = 0;
+                }
+
+                curr_path <<= PATH_ELEM_SIZE;
+                curr_path |= idx;
+            }
+
+            if (path_digits) {
+                path_digits[0] = curr_path;
+                path = make_big(hp);
+            } else {
+                /* The Uint could be too large for a small */
+                path = erts_make_integer(curr_path, BIF_P);
+            }
+
+            if (type == iterator) {
+                hp = HAlloc(BIF_P, 2);
+                *path_ptr = CONS(hp, path, map); hp += 2;
+            } else {
+                hp = HAlloc(BIF_P, 4);
+                res = CONS(hp, map, res); hp += 2;
+                res = CONS(hp, path, res); hp += 2;
+            }
+        } else {
+            if (type == iterator) {
+                HRelease(BIF_P, hp + 4 * elems, hp);
+            } else {
+                HRelease(BIF_P, hp + (2+3) * elems, hp);
+            }
+        }
+        BIF_P->fcalls -= 4 * (orig_elems - elems);
+        DESTROY_WSTACK(stack);
+        BIF_RET(res);
+
+    badarg:
+        if (type == iterator) {
+            HRelease(BIF_P, hp + 4 * elems, hp);
+        } else {
+            HRelease(BIF_P, hp + (2+3) * elems, hp);
+        }
+        BIF_P->fcalls -= 4 * (orig_elems - elems);
+        DESTROY_WSTACK(stack);
+        BIF_ERROR(BIF_P, BADARG);
+    }
+}
+
 /* implementation of builtin emulations */
 
 #if !ERTS_AT_LEAST_GCC_VSN__(3, 4, 0)
diff --git a/erts/emulator/beam/erl_map.h b/erts/emulator/beam/erl_map.h
index c3ccf80b85..718d400e22 100644
--- a/erts/emulator/beam/erl_map.h
+++ b/erts/emulator/beam/erl_map.h
@@ -64,7 +64,6 @@ typedef struct flatmap_s {
 #define hashmap_shift_hash(Heap,Hx,Lvl,Key) \
     (((++(Lvl)) & 7) ? (Hx) >> 4 : hashmap_make_hash(CONS(Heap, make_small((Lvl)>>3), Key)))
 
-
 /* erl_term.h stuff */
 #define flatmap_get_values(x)        (((Eterm *)(x)) + sizeof(flatmap_t)/sizeof(Eterm))
 #define flatmap_get_keys(x)          (((Eterm *)tuple_val(((flatmap_t *)(x))->keys)) + 1)
diff --git a/erts/emulator/beam/erl_message.c b/erts/emulator/beam/erl_message.c
index b30c4a49d7..abf194cf94 100644
--- a/erts/emulator/beam/erl_message.c
+++ b/erts/emulator/beam/erl_message.c
@@ -170,7 +170,7 @@ erts_cleanup_offheap(ErlOffHeap *offheap)
             erts_bin_release(u.pb->val);
 	    break;
 	case FUN_SUBTAG:
-	    if (erts_smp_refc_dectest(&u.fun->fe->refc, 0) == 0) {
+	    if (erts_refc_dectest(&u.fun->fe->refc, 0) == 0) {
 		erts_erase_fun_entry(u.fun->fe);		    
 	    }
 	    break;
@@ -265,11 +265,9 @@ erts_queue_dist_message(Process *rcvr,
     Sint tok_lastcnt = 0;
     Sint tok_serial = 0;
 #endif
-#ifdef ERTS_SMP
     erts_aint_t state;
-#endif
 
-    ERTS_SMP_LC_ASSERT(rcvr_locks == erts_proc_lc_my_proc_locks(rcvr));
+    ERTS_LC_ASSERT(rcvr_locks == erts_proc_lc_my_proc_locks(rcvr));
 
     mp = erts_alloc_message(0, NULL);
     mp->data.dist_ext = dist_ext;
@@ -283,36 +281,34 @@ erts_queue_dist_message(Process *rcvr,
 #endif
 	ERL_MESSAGE_TOKEN(mp) = token;
 
-#ifdef ERTS_SMP
     if (!(rcvr_locks & ERTS_PROC_LOCK_MSGQ)) {
-	if (erts_smp_proc_trylock(rcvr, ERTS_PROC_LOCK_MSGQ) == EBUSY) {
+	if (erts_proc_trylock(rcvr, ERTS_PROC_LOCK_MSGQ) == EBUSY) {
 	    ErtsProcLocks need_locks = ERTS_PROC_LOCK_MSGQ;
             ErtsProcLocks unlocks =
                 rcvr_locks & ERTS_PROC_LOCKS_HIGHER_THAN(ERTS_PROC_LOCK_MSGQ);
 	    if (unlocks) {
-		erts_smp_proc_unlock(rcvr, unlocks);
+		erts_proc_unlock(rcvr, unlocks);
 		need_locks |= unlocks;
 	    }
-	    erts_smp_proc_lock(rcvr, need_locks);
+	    erts_proc_lock(rcvr, need_locks);
 	}
     }
 
-    state = erts_smp_atomic32_read_acqb(&rcvr->state);
+    state = erts_atomic32_read_acqb(&rcvr->state);
     if (state & (ERTS_PSFLG_PENDING_EXIT|ERTS_PSFLG_EXITING)) {
 	if (!(rcvr_locks & ERTS_PROC_LOCK_MSGQ))
-	    erts_smp_proc_unlock(rcvr, ERTS_PROC_LOCK_MSGQ);
+	    erts_proc_unlock(rcvr, ERTS_PROC_LOCK_MSGQ);
 	/* Drop message if receiver is exiting or has a pending exit ... */
 	erts_cleanup_messages(mp);
     }
     else
-#endif
     if (IS_TRACED_FL(rcvr, F_TRACE_RECEIVE)) {
         if (from == am_Empty)
             from = dist_ext->dep->sysname;
 
 	/* Ahh... need to decode it in order to trace it... */
 	if (!(rcvr_locks & ERTS_PROC_LOCK_MSGQ))
-	    erts_smp_proc_unlock(rcvr, ERTS_PROC_LOCK_MSGQ);
+	    erts_proc_unlock(rcvr, ERTS_PROC_LOCK_MSGQ);
 	if (!erts_decode_dist_message(rcvr, rcvr_locks, mp, 0))
 	    erts_free_message(mp);
 	else {
@@ -361,14 +357,10 @@ erts_queue_dist_message(Process *rcvr,
 	LINK_MESSAGE(rcvr, mp, &mp->next, 1);
 
 	if (!(rcvr_locks & ERTS_PROC_LOCK_MSGQ))
-	    erts_smp_proc_unlock(rcvr, ERTS_PROC_LOCK_MSGQ);
+	    erts_proc_unlock(rcvr, ERTS_PROC_LOCK_MSGQ);
 
 	erts_proc_notify_new_message(rcvr,
-#ifdef ERTS_SMP
 				     rcvr_locks
-#else
-				     0
-#endif
 	    );
     }
 }
@@ -393,50 +385,45 @@ queue_messages(Process* receiver,
            ERL_MESSAGE_TOKEN(first) == NIL ||
            is_tuple(ERL_MESSAGE_TOKEN(first)));
 
-#ifdef ERTS_SMP
 #ifdef ERTS_ENABLE_LOCK_CHECK
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(receiver) < ERTS_PROC_LOCK_MSGQ ||
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(receiver) < ERTS_PROC_LOCK_MSGQ ||
                        receiver_locks == erts_proc_lc_my_proc_locks(receiver));
 #endif
 
     if (!(receiver_locks & ERTS_PROC_LOCK_MSGQ)) {
-	if (erts_smp_proc_trylock(receiver, ERTS_PROC_LOCK_MSGQ) == EBUSY) {
+	if (erts_proc_trylock(receiver, ERTS_PROC_LOCK_MSGQ) == EBUSY) {
             ErtsProcLocks need_locks;
 
 	    if (receiver_state)
 		state = *receiver_state;
 	    else
-		state = erts_smp_atomic32_read_nob(&receiver->state);
+		state = erts_atomic32_read_nob(&receiver->state);
 	    if (state & (ERTS_PSFLG_EXITING|ERTS_PSFLG_PENDING_EXIT))
 		goto exiting;
 
             need_locks = receiver_locks & ERTS_PROC_LOCKS_HIGHER_THAN(ERTS_PROC_LOCK_MSGQ);
 	    if (need_locks) {
-		erts_smp_proc_unlock(receiver, need_locks);
+		erts_proc_unlock(receiver, need_locks);
 	    }
             need_locks |= ERTS_PROC_LOCK_MSGQ;
-	    erts_smp_proc_lock(receiver, need_locks);
+	    erts_proc_lock(receiver, need_locks);
 	}
 	locked_msgq = 1;
     }
 
-#endif
 
-    state = erts_smp_atomic32_read_nob(&receiver->state);
+    state = erts_atomic32_read_nob(&receiver->state);
 
     if (state & (ERTS_PSFLG_PENDING_EXIT|ERTS_PSFLG_EXITING)) {
-#ifdef ERTS_SMP
     exiting:
-#endif
 	/* Drop message if receiver is exiting or has a pending exit... */
 	if (locked_msgq)
-	    erts_smp_proc_unlock(receiver, ERTS_PROC_LOCK_MSGQ);
+	    erts_proc_unlock(receiver, ERTS_PROC_LOCK_MSGQ);
 	erts_cleanup_messages(first);
 	return 0;
     }
 
     res = receiver->msg.len;
-#ifdef ERTS_SMP
     if (receiver_locks & ERTS_PROC_LOCK_MAIN) {
 	/*
 	 * We move 'in queue' to 'private queue' and place
@@ -447,11 +434,10 @@ queue_messages(Process* receiver,
 	 * the root set when garbage collecting.
 	 */
 	res += receiver->msg_inq.len;
-	ERTS_SMP_MSGQ_MV_INQ2PRIVQ(receiver);
+	ERTS_MSGQ_MV_INQ2PRIVQ(receiver);
         LINK_MESSAGE_PRIVQ(receiver, first, last, len);
     }
     else
-#endif
     {
 	LINK_MESSAGE(receiver, first, last, len);
     }
@@ -489,14 +475,10 @@ queue_messages(Process* receiver,
 
     }
     if (locked_msgq) {
-	erts_smp_proc_unlock(receiver, ERTS_PROC_LOCK_MSGQ);
+	erts_proc_unlock(receiver, ERTS_PROC_LOCK_MSGQ);
     }
 
-#ifdef ERTS_SMP
     erts_proc_notify_new_message(receiver, receiver_locks);
-#else
-    erts_proc_notify_new_message(receiver, 0);
-#endif
     return res;
 }
 
@@ -594,9 +576,7 @@ erts_try_alloc_message_on_heap(Process *pp,
 			       ErlOffHeap **ohpp,
 			       int *on_heap_p)
 {
-#ifdef ERTS_SMP
     int locked_main = 0;
-#endif
     ErtsMessage *mp;
 
     ASSERT(!(*psp & ERTS_PSFLG_OFF_HEAP_MSGQ));
@@ -604,15 +584,9 @@ erts_try_alloc_message_on_heap(Process *pp,
     if ((*psp) & ERTS_PSFLGS_VOLATILE_HEAP)
 	goto in_message_fragment;
     else if (
-#if defined(ERTS_SMP)
 	*plp & ERTS_PROC_LOCK_MAIN
-#else
-	pp
-#endif
 	) {
-#ifdef ERTS_SMP
     try_on_heap:
-#endif
 	if (((*psp) & ERTS_PSFLGS_VOLATILE_HEAP)
 	    || (pp->flags & F_DISABLE_GC)
 	    || HEAP_LIMIT(pp) - HEAP_TOP(pp) <= sz) {
@@ -620,12 +594,10 @@ erts_try_alloc_message_on_heap(Process *pp,
 	     * The heap is either potentially in an inconsistent
 	     * state, or not large enough.
 	     */
-#ifdef ERTS_SMP
 	    if (locked_main) {
 		*plp &= ~ERTS_PROC_LOCK_MAIN;
-		erts_smp_proc_unlock(pp, ERTS_PROC_LOCK_MAIN);
+		erts_proc_unlock(pp, ERTS_PROC_LOCK_MAIN);
 	    }
-#endif
 	    goto in_message_fragment;
 	}
 
@@ -636,14 +608,12 @@ erts_try_alloc_message_on_heap(Process *pp,
 	mp->data.attached = NULL;
 	*on_heap_p = !0;
     }
-#ifdef ERTS_SMP
-    else if (pp && erts_smp_proc_trylock(pp, ERTS_PROC_LOCK_MAIN) == 0) {
+    else if (pp && erts_proc_trylock(pp, ERTS_PROC_LOCK_MAIN) == 0) {
 	locked_main = 1;
-	*psp = erts_smp_atomic32_read_nob(&pp->state);
+	*psp = erts_atomic32_read_nob(&pp->state);
 	*plp |= ERTS_PROC_LOCK_MAIN;
 	goto try_on_heap;
     }
-#endif
     else {
     in_message_fragment:
 	if (!((*psp) & ERTS_PSFLG_ON_HEAP_MSGQ)) {
@@ -712,7 +682,7 @@ erts_send_message(Process* sender,
     }
 #endif
 
-    receiver_state = erts_smp_atomic32_read_nob(&receiver->state);
+    receiver_state = erts_atomic32_read_nob(&receiver->state);
 
     if (SEQ_TRACE_TOKEN(sender) != NIL && !(flags & ERTS_SND_FLG_NO_SEQ_TRACE)) {
         Eterm* hp;
@@ -961,7 +931,7 @@ erts_move_messages_off_heap(Process *c_p)
 
     reds += c_p->msg.len / 10;
 
-    ASSERT(erts_smp_atomic32_read_nob(&c_p->state)
+    ASSERT(erts_atomic32_read_nob(&c_p->state)
 	   & ERTS_PSFLG_OFF_HEAP_MSGQ);
     ASSERT(c_p->flags & F_OFF_HEAP_MSGQ_CHNG);
 
@@ -1026,9 +996,9 @@ erts_complete_off_heap_message_queue_change(Process *c_p)
 {
     int reds = 1;
 
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(c_p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(c_p));
     ASSERT(c_p->flags & F_OFF_HEAP_MSGQ_CHNG);
-    ASSERT(erts_smp_atomic32_read_nob(&c_p->state) & ERTS_PSFLG_OFF_HEAP_MSGQ);
+    ASSERT(erts_atomic32_read_nob(&c_p->state) & ERTS_PSFLG_OFF_HEAP_MSGQ);
 
     /*
      * This job was first initiated when the process changed to off heap
@@ -1040,13 +1010,13 @@ erts_complete_off_heap_message_queue_change(Process *c_p)
      */
 
     if (!(c_p->flags & F_OFF_HEAP_MSGQ))
-	erts_smp_atomic32_read_band_nob(&c_p->state,
+	erts_atomic32_read_band_nob(&c_p->state,
 					~ERTS_PSFLG_OFF_HEAP_MSGQ);
     else {
 	reds += 2;
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ);
-	ERTS_SMP_MSGQ_MV_INQ2PRIVQ(c_p);
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ);
+	erts_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ);
+	ERTS_MSGQ_MV_INQ2PRIVQ(c_p);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ);
 	reds += erts_move_messages_off_heap(c_p);
     }
     c_p->flags &= ~F_OFF_HEAP_MSGQ_CHNG;
@@ -1083,16 +1053,16 @@ erts_change_message_queue_management(Process *c_p, Eterm new_state)
 
 #ifdef DEBUG
     if (c_p->flags & F_OFF_HEAP_MSGQ) {
-	ASSERT(erts_smp_atomic32_read_nob(&c_p->state)
+	ASSERT(erts_atomic32_read_nob(&c_p->state)
 	       & ERTS_PSFLG_OFF_HEAP_MSGQ);
     }
     else {
 	if (c_p->flags & F_OFF_HEAP_MSGQ_CHNG) {
-	    ASSERT(erts_smp_atomic32_read_nob(&c_p->state)
+	    ASSERT(erts_atomic32_read_nob(&c_p->state)
 		   & ERTS_PSFLG_OFF_HEAP_MSGQ);
 	}
 	else {
-	    ASSERT(!(erts_smp_atomic32_read_nob(&c_p->state)
+	    ASSERT(!(erts_atomic32_read_nob(&c_p->state)
 		     & ERTS_PSFLG_OFF_HEAP_MSGQ));
 	}
     }
@@ -1109,7 +1079,7 @@ erts_change_message_queue_management(Process *c_p, Eterm new_state)
 	case am_on_heap:
 	    c_p->flags |= F_ON_HEAP_MSGQ;
 	    c_p->flags &= ~F_OFF_HEAP_MSGQ;
-	    erts_smp_atomic32_read_bor_nob(&c_p->state,
+	    erts_atomic32_read_bor_nob(&c_p->state,
 					   ERTS_PSFLG_ON_HEAP_MSGQ);
 	    /*
 	     * We are not allowed to clear ERTS_PSFLG_OFF_HEAP_MSGQ
@@ -1118,7 +1088,7 @@ erts_change_message_queue_management(Process *c_p, Eterm new_state)
 	     */
 	    if (!(c_p->flags & F_OFF_HEAP_MSGQ_CHNG)) {
 		/* Safe to clear ERTS_PSFLG_OFF_HEAP_MSGQ... */
-		erts_smp_atomic32_read_band_nob(&c_p->state,
+		erts_atomic32_read_band_nob(&c_p->state,
 						~ERTS_PSFLG_OFF_HEAP_MSGQ);
 	    }
 	    break;
@@ -1136,7 +1106,7 @@ erts_change_message_queue_management(Process *c_p, Eterm new_state)
 	    break;
 	case am_off_heap:
 	    c_p->flags &= ~F_ON_HEAP_MSGQ;
-	    erts_smp_atomic32_read_band_nob(&c_p->state,
+	    erts_atomic32_read_band_nob(&c_p->state,
 					    ~ERTS_PSFLG_ON_HEAP_MSGQ);
 	    goto change_to_off_heap;
 	default:
@@ -1171,7 +1141,7 @@ change_to_off_heap:
 	 * change has completed, GC does not need to inspect
 	 * the message queue at all.
 	 */
-	erts_smp_atomic32_read_bor_nob(&c_p->state,
+	erts_atomic32_read_bor_nob(&c_p->state,
 				       ERTS_PSFLG_OFF_HEAP_MSGQ);
 	c_p->flags |= F_OFF_HEAP_MSGQ_CHNG;
 	cohmq = erts_alloc(ERTS_ALC_T_MSGQ_CHNG,
@@ -1452,7 +1422,7 @@ erts_factory_message_create(ErtsHeapFactory* factory,
     int on_heap;
     erts_aint32_t state;
 
-    state = proc ? erts_smp_atomic32_read_nob(&proc->state) : 0;
+    state = proc ? erts_atomic32_read_nob(&proc->state) : 0;
 
     if (state & ERTS_PSFLG_OFF_HEAP_MSGQ) {
 	msgp = erts_alloc_message(sz, &hp);
@@ -1467,7 +1437,7 @@ erts_factory_message_create(ErtsHeapFactory* factory,
     }
 
     if (on_heap) {
-	ERTS_SMP_ASSERT(*proc_locksp & ERTS_PROC_LOCK_MAIN);
+	ERTS_ASSERT(*proc_locksp & ERTS_PROC_LOCK_MAIN);
 	ASSERT(ohp == &proc->off_heap);
 	factory->mode = FACTORY_HALLOC;
 	factory->p = proc;
diff --git a/erts/emulator/beam/erl_message.h b/erts/emulator/beam/erl_message.h
index 42ed14e69c..a14f4f51d8 100644
--- a/erts/emulator/beam/erl_message.h
+++ b/erts/emulator/beam/erl_message.h
@@ -167,14 +167,12 @@ typedef struct {
     Sint len;            /* queue length */
 
     /*
-     * The following two fields are used by the recv_mark/1 and
+     * The following field is used by the recv_mark/1 and
      * recv_set/1 instructions.
      */
-    BeamInstr* mark;		/* address to rec_loop/2 instruction */
     ErtsMessage** saved_last;	/* saved last pointer */
 } ErlMessageQueue;
 
-#ifdef ERTS_SMP
 
 typedef struct {
     ErtsMessage* first;
@@ -190,7 +188,6 @@ typedef struct erl_trace_message_queue__ {
     Sint len;            /* queue length */
 } ErlTraceMessageQueue;
 
-#endif
 
 /* Get "current" message */
 #define PEEK_MESSAGE(p)  (*(p)->msg.save)
@@ -207,7 +204,6 @@ typedef struct erl_trace_message_queue__ {
         (p)->where.len += (num_msgs);                                   \
     } while(0)
 
-#ifdef ERTS_SMP
 
 /* Add message last in private message queue */
 #define LINK_MESSAGE_PRIVQ(p, first_msg, last_msg, len)                 \
@@ -219,7 +215,7 @@ typedef struct erl_trace_message_queue__ {
 #define LINK_MESSAGE(p, first_msg, last_msg, len)       \
     LINK_MESSAGE_IMPL(p, first_msg, last_msg, len, msg_inq)
 
-#define ERTS_SMP_MSGQ_MV_INQ2PRIVQ(p)                   \
+#define ERTS_MSGQ_MV_INQ2PRIVQ(p)                   \
     do {                                                \
         if (p->msg_inq.first) {                         \
             *p->msg.last = p->msg_inq.first;            \
@@ -231,17 +227,6 @@ typedef struct erl_trace_message_queue__ {
         }                                               \
     } while (0)
 
-#else
-
-#define ERTS_SMP_MSGQ_MV_INQ2PRIVQ(p)
-
-/* Add message last_msg in message queue */
-#define LINK_MESSAGE(p, first_msg, last_msg, len)                       \
-    do {                                                                \
-        LINK_MESSAGE_IMPL(p, first_msg, last_msg, len, msg);            \
-    } while(0)
-
-#endif
 
 /* Unlink current message */
 #define UNLINK_MESSAGE(p,msgp) do { \
@@ -250,12 +235,17 @@ typedef struct erl_trace_message_queue__ {
      (p)->msg.len--; \
      if (__mp == NULL) \
          (p)->msg.last = (p)->msg.save; \
-     (p)->msg.mark = 0; \
 } while(0)
 
-/* Reset message save point (after receive match) */
-#define JOIN_MESSAGE(p) \
-     (p)->msg.save = &(p)->msg.first
+/*
+ * Reset message save point (after receive match).
+ * Also invalidate the saved position since it may no
+ * longer be safe to use.
+ */
+#define JOIN_MESSAGE(p) do {                    \
+    (p)->msg.save = &(p)->msg.first;            \
+    (p)->msg.saved_last = 0;                    \
+} while(0)
 
 /* Save current message */
 #define SAVE_MESSAGE(p) \
diff --git a/erts/emulator/beam/erl_monitors.c b/erts/emulator/beam/erl_monitors.c
index 3994800ba7..1c840d89f6 100644
--- a/erts/emulator/beam/erl_monitors.c
+++ b/erts/emulator/beam/erl_monitors.c
@@ -54,7 +54,7 @@
 #define DIR_RIGHT 1
 #define DIR_END 2 
 
-static erts_smp_atomic_t tot_link_lh_size;
+static erts_atomic_t tot_link_lh_size;
 
 /* Implements the sort order in monitor trees, which is different from 
    the ordinary term order.
@@ -123,7 +123,7 @@ do {								\
 	    (*((Hp)++)) = boxed_val((From))[i__];		\
 	if (is_external((To))) {				\
 	    external_thing_ptr((To))->next = NULL;		\
-	    erts_smp_refc_inc(&(external_thing_ptr((To))->node->refc), 2);\
+	    erts_refc_inc(&(external_thing_ptr((To))->node->refc), 2);\
 	}							\
     }								\
 } while (0)
@@ -145,7 +145,7 @@ static ErtsMonitor *create_monitor(Uint type, Eterm ref, UWord entity, Eterm nam
      } else {
 	 n = (ErtsMonitor *) erts_alloc(ERTS_ALC_T_MONITOR_LH,
 					mon_size*sizeof(Uint));
-	 erts_smp_atomic_add_nob(&tot_link_lh_size, mon_size*sizeof(Uint));
+	 erts_atomic_add_nob(&tot_link_lh_size, mon_size*sizeof(Uint));
      } 
      hp = n->heap;
 
@@ -179,7 +179,7 @@ static ErtsLink *create_link(Uint type, Eterm pid)
      } else {
 	 n = (ErtsLink *) erts_alloc(ERTS_ALC_T_NLINK_LH,
 				     lnk_size*sizeof(Uint));
-	 erts_smp_atomic_add_nob(&tot_link_lh_size, lnk_size*sizeof(Uint));
+	 erts_atomic_add_nob(&tot_link_lh_size, lnk_size*sizeof(Uint));
      } 
      hp = n->heap;
 
@@ -214,13 +214,13 @@ static ErtsSuspendMonitor *create_suspend_monitor(Eterm pid)
 void
 erts_init_monitors(void)
 {
-    erts_smp_atomic_init_nob(&tot_link_lh_size, 0);
+    erts_atomic_init_nob(&tot_link_lh_size, 0);
 }
 
 Uint
 erts_tot_link_lh_size(void)
 {
-    return (Uint) erts_smp_atomic_read_nob(&tot_link_lh_size);
+    return (Uint) erts_atomic_read_nob(&tot_link_lh_size);
 }
 
 void erts_destroy_monitor(ErtsMonitor *mon)
@@ -245,7 +245,7 @@ void erts_destroy_monitor(ErtsMonitor *mon)
 	erts_free(ERTS_ALC_T_MONITOR_SH, (void *) mon);
     } else {
 	erts_free(ERTS_ALC_T_MONITOR_LH, (void *) mon);
-	erts_smp_atomic_add_nob(&tot_link_lh_size, -1*mon_size*sizeof(Uint));
+	erts_atomic_add_nob(&tot_link_lh_size, -1*mon_size*sizeof(Uint));
     }
 }
     
@@ -267,7 +267,7 @@ void erts_destroy_link(ErtsLink *lnk)
 	erts_free(ERTS_ALC_T_NLINK_SH, (void *) lnk);
     } else {
 	erts_free(ERTS_ALC_T_NLINK_LH, (void *) lnk);
-	erts_smp_atomic_add_nob(&tot_link_lh_size, -1*lnk_size*sizeof(Uint));
+	erts_atomic_add_nob(&tot_link_lh_size, -1*lnk_size*sizeof(Uint));
     }
 }
 
@@ -985,15 +985,14 @@ Eterm erts_debug_dump_monitors_1(BIF_ALIST_1)
     DistEntry *dep;
     rp = erts_pid2proc(p, ERTS_PROC_LOCK_MAIN, pid, ERTS_PROC_LOCK_LINK);
     if (!rp) {
-	ERTS_SMP_ASSERT_IS_NOT_EXITING(p);
+	ERTS_ASSERT_IS_NOT_EXITING(p);
 	if (is_atom(pid) && is_node_name_atom(pid) &&
 	    (dep = erts_find_dist_entry(pid)) != NULL) {
 	    erts_printf("Dumping dist monitors-------------------\n");
-	    erts_smp_de_links_lock(dep);
+	    erts_de_links_lock(dep);
 	    erts_dump_monitors(dep->monitors,0);
-	    erts_smp_de_links_unlock(dep);
+	    erts_de_links_unlock(dep);
 	    erts_printf("Monitors dumped-------------------------\n");
-	    erts_deref_dist_entry(dep);
 	    BIF_RET(am_true);
 	} else {
 	    BIF_ERROR(p,BADARG);
@@ -1002,7 +1001,7 @@ Eterm erts_debug_dump_monitors_1(BIF_ALIST_1)
 	erts_printf("Dumping pid monitors--------------------\n");
 	erts_dump_monitors(ERTS_P_MONITORS(rp),0);
 	erts_printf("Monitors dumped-------------------------\n");
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 	BIF_RET(am_true);
     }
 }
@@ -1030,15 +1029,14 @@ Eterm erts_debug_dump_links_1(BIF_ALIST_1)
     } else {
 	rp = erts_pid2proc(p, ERTS_PROC_LOCK_MAIN, pid, ERTS_PROC_LOCK_LINK);
 	if (!rp) {
-	    ERTS_SMP_ASSERT_IS_NOT_EXITING(p);
+	    ERTS_ASSERT_IS_NOT_EXITING(p);
 	    if (is_atom(pid) && is_node_name_atom(pid) &&
 		(dep = erts_find_dist_entry(pid)) != NULL) {
 		erts_printf("Dumping dist links----------------------\n");
-		erts_smp_de_links_lock(dep);
+		erts_de_links_lock(dep);
 		erts_dump_links(dep->nlinks,0);
-		erts_smp_de_links_unlock(dep);
+		erts_de_links_unlock(dep);
 		erts_printf("Links dumped----------------------------\n");
-		erts_deref_dist_entry(dep);
 		BIF_RET(am_true);
 	    } else {
 		BIF_ERROR(p,BADARG);
@@ -1048,7 +1046,7 @@ Eterm erts_debug_dump_links_1(BIF_ALIST_1)
 	    erts_printf("Dumping pid links-----------------------\n");
 	    erts_dump_links(ERTS_P_LINKS(rp), 0);
 	    erts_printf("Links dumped----------------------------\n");
-	    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	    erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 	    BIF_RET(am_true);
 	}
     }
diff --git a/erts/emulator/beam/erl_msacc.c b/erts/emulator/beam/erl_msacc.c
index 6c477be615..d659842b7e 100644
--- a/erts/emulator/beam/erl_msacc.c
+++ b/erts/emulator/beam/erl_msacc.c
@@ -48,11 +48,7 @@ static Eterm erts_msacc_gather_stats(ErtsMsAcc *msacc, ErtsHeapFactory *factory)
 static void erts_msacc_reset(ErtsMsAcc *msacc);
 static ErtsMsAcc* get_msacc(void);
 
-#ifdef USE_THREADS
 erts_tsd_key_t ERTS_WRITE_UNLIKELY(erts_msacc_key);
-#else
-ErtsMsAcc *ERTS_WRITE_UNLIKELY(erts_msacc) = NULL;
-#endif
 #ifndef ERTS_MSACC_ALWAYS_ON
 int ERTS_WRITE_UNLIKELY(erts_msacc_enabled);
 #endif
@@ -60,10 +56,8 @@ int ERTS_WRITE_UNLIKELY(erts_msacc_enabled);
 static Eterm *erts_msacc_state_atoms = NULL;
 static erts_rwmtx_t msacc_mutex;
 static ErtsMsAcc *msacc_managed = NULL;
-#ifdef USE_THREADS
 static ErtsMsAcc *msacc_unmanaged = NULL;
 static Uint msacc_unmanaged_count = 0;
-#endif
 
 #if ERTS_MSACC_STATE_COUNT < MAP_SMALL_MAP_LIMIT
 #define DEFAULT_MSACC_MSG_SIZE (3 + 1 + ERTS_MSACC_STATE_COUNT * 2 + 3 + ERTS_REF_THING_SIZE)
@@ -78,11 +72,7 @@ void erts_msacc_early_init(void) {
 #endif
     erts_rwmtx_init(&msacc_mutex, "msacc_list_mutex", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_DEBUG);
-#ifdef USE_THREADS
     erts_tsd_key_create(&erts_msacc_key,"erts_msacc_key");
-#else
-    erts_msacc = NULL;
-#endif
 }
 
 void erts_msacc_init(void) {
@@ -107,7 +97,6 @@ void erts_msacc_init_thread(char *type, int id, int managed) {
     msacc->tid = erts_thr_self();
     msacc->perf_counter = 0;
 
-#ifdef USE_THREADS
     erts_rwmtx_rwlock(&msacc_mutex);
     if (!managed) {
         erts_mtx_init(&msacc->mtx, "msacc_unmanaged_mutex", NIL,
@@ -121,9 +110,6 @@ void erts_msacc_init_thread(char *type, int id, int managed) {
         msacc_managed = msacc;
     }
     erts_rwmtx_rwunlock(&msacc_mutex);
-#else
-    msacc_managed = msacc;
-#endif
 
     erts_msacc_reset(msacc);
 
@@ -216,7 +202,7 @@ typedef struct {
     Eterm ref;
     Eterm ref_heap[ERTS_REF_THING_SIZE];
     Uint req_sched;
-    erts_smp_atomic32_t refc;
+    erts_atomic32_t refc;
 } ErtsMSAccReq;
 
 static ErtsMsAcc* get_msacc(void) {
@@ -267,7 +253,7 @@ static void send_reply(ErtsMsAcc *msacc, ErtsMSAccReq *msaccrp) {
 	rp_locks &= ~ERTS_PROC_LOCK_MAIN;
 
     if (rp_locks)
-	erts_smp_proc_unlock(rp, rp_locks);
+	erts_proc_unlock(rp, rp_locks);
 
 }
 
@@ -303,7 +289,7 @@ reply_msacc(void *vmsaccrp)
 
     erts_proc_dec_refc(msaccrp->proc);
 
-    if (erts_smp_atomic32_dec_read_nob(&msaccrp->refc) == 0)
+    if (erts_atomic32_dec_read_nob(&msaccrp->refc) == 0)
       erts_free(ERTS_ALC_T_MSACC, vmsaccrp);
 }
 
@@ -370,14 +356,10 @@ erts_msacc_request(Process *c_p, int action, Eterm *threads)
     msaccrp->ref = STORE_NC(&hp, NULL, ref);
     msaccrp->req_sched = esdp->no;
 
-#ifdef ERTS_SMP
     *threads = erts_no_schedulers;
     *threads += 1; /* aux thread */
-#else
-    *threads = 1;
-#endif
 
-    erts_smp_atomic32_init_nob(&msaccrp->refc,(erts_aint32_t)*threads);
+    erts_atomic32_init_nob(&msaccrp->refc,(erts_aint32_t)*threads);
 
     erts_proc_add_refc(c_p, *threads);
 
@@ -386,12 +368,9 @@ erts_msacc_request(Process *c_p, int action, Eterm *threads)
                                           erts_no_schedulers,
                                           reply_msacc,
                                           (void *) msaccrp);
-#ifdef ERTS_SMP
     /* aux thread */
     erts_schedule_misc_aux_work(0, reply_msacc, (void *) msaccrp);
-#endif
 
-#ifdef USE_THREADS
     /* Manage unmanaged threads */
     switch (action) {
     case ERTS_MSACC_GATHER: {
@@ -468,7 +447,6 @@ erts_msacc_request(Process *c_p, int action, Eterm *threads)
     default: { ASSERT(0); }
     }
 
-#endif
 
     *threads = make_small(*threads);
 
diff --git a/erts/emulator/beam/erl_msacc.h b/erts/emulator/beam/erl_msacc.h
index 3f6273f214..2588dec903 100644
--- a/erts/emulator/beam/erl_msacc.h
+++ b/erts/emulator/beam/erl_msacc.h
@@ -159,11 +159,7 @@ struct erl_msacc_t_ {
 
 #ifdef ERTS_ENABLE_MSACC
 
-#ifdef USE_THREADS
 extern erts_tsd_key_t erts_msacc_key;
-#else
-extern ErtsMsAcc *erts_msacc;
-#endif
 
 #ifdef ERTS_MSACC_ALWAYS_ON
 #define erts_msacc_enabled 1
@@ -171,13 +167,8 @@ extern ErtsMsAcc *erts_msacc;
 extern int erts_msacc_enabled;
 #endif
 
-#ifdef USE_THREADS
 #define ERTS_MSACC_TSD_GET() erts_tsd_get(erts_msacc_key)
 #define ERTS_MSACC_TSD_SET(tsd) erts_tsd_set(erts_msacc_key,tsd)
-#else
-#define ERTS_MSACC_TSD_GET() erts_msacc
-#define ERTS_MSACC_TSD_SET(tsd) erts_msacc = tsd
-#endif
 
 void erts_msacc_early_init(void);
 void erts_msacc_init(void);
@@ -341,8 +332,8 @@ ERTS_GLB_INLINE
 void erts_msacc_set_state_um__(ErtsMsAcc *msacc, Uint new_state, int increment) {
     if (ERTS_UNLIKELY(msacc->unmanaged)) {
         erts_mtx_lock(&msacc->mtx);
-        msacc->state = new_state;
         if (ERTS_LIKELY(!msacc->perf_counter)) {
+            msacc->state = new_state;
             erts_mtx_unlock(&msacc->mtx);
             return;
         }
diff --git a/erts/emulator/beam/erl_nfunc_sched.c b/erts/emulator/beam/erl_nfunc_sched.c
index 1bebc1eda4..f97e86bf95 100644
--- a/erts/emulator/beam/erl_nfunc_sched.c
+++ b/erts/emulator/beam/erl_nfunc_sched.c
@@ -113,7 +113,7 @@ erts_nif_export_schedule(Process *c_p, Process *dirty_shadow_proc,
     NifExport* nep;
     int i;
 
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p)
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p)
 		       & ERTS_PROC_LOCK_MAIN);
 
     if (dirty_shadow_proc) {
diff --git a/erts/emulator/beam/erl_nfunc_sched.h b/erts/emulator/beam/erl_nfunc_sched.h
index 55a3a6dbf6..b8a4e4ebc3 100644
--- a/erts/emulator/beam/erl_nfunc_sched.h
+++ b/erts/emulator/beam/erl_nfunc_sched.h
@@ -144,9 +144,9 @@ ERTS_GLB_INLINE void
 erts_nif_export_restore(Process *c_p, NifExport *ep, Eterm result)
 {
     ASSERT(!ERTS_SCHEDULER_IS_DIRTY(erts_get_scheduler_data()));
-    ERTS_SMP_LC_ASSERT(!(c_p->static_flags
+    ERTS_LC_ASSERT(!(c_p->static_flags
 			 & ERTS_STC_FLG_SHADOW_PROC));
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p)
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p)
 		       & ERTS_PROC_LOCK_MAIN);
 
     c_p->current = ep->current;
@@ -193,7 +193,6 @@ erts_nif_export_check_save_trace(Process *c_p, Eterm result,
 ERTS_GLB_INLINE Process *
 erts_proc_shadow2real(Process *c_p)
 {
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (c_p->static_flags & ERTS_STC_FLG_SHADOW_PROC) {
 	Process *real_c_p = c_p->next;
 	ASSERT(ERTS_SCHEDULER_IS_DIRTY(erts_get_scheduler_data()));
@@ -201,7 +200,6 @@ erts_proc_shadow2real(Process *c_p)
 	return real_c_p;
     }
     ASSERT(!ERTS_SCHEDULER_IS_DIRTY(erts_get_scheduler_data()));
-#endif
     return c_p;
 }
 
@@ -213,11 +211,10 @@ erts_proc_shadow2real(Process *c_p)
 #define ERTS_NFUNC_SCHED_INTERNALS__
 
 #define ERTS_I_BEAM_OP_TO_NIF_EXPORT(I)					\
-    (ASSERT(BeamOp(op_apply_bif) == (BeamInstr *) (*(I))		\
-	    || BeamOp(op_call_nif) == (BeamInstr *) (*(I))),		\
+    (ASSERT(BeamIsOpCode(*(I), op_apply_bif) ||                         \
+            BeamIsOpCode(*(I), op_call_nif)),                           \
      ((NifExport *) (((char *) (I)) - offsetof(NifExport, exp.beam[0]))))
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 #include "erl_message.h"
 #include <stddef.h>
@@ -235,7 +232,7 @@ erts_flush_dirty_shadow_proc(Process *sproc)
     Process *c_p = sproc->next;
 
     ASSERT(sproc->common.id == c_p->common.id);
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p)
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p)
 		       & ERTS_PROC_LOCK_MAIN);
 
     ASSERT(c_p->stop == sproc->stop);
@@ -283,7 +280,7 @@ erts_cache_dirty_shadow_proc(Process *sproc)
     Process *c_p = sproc->next;
     ASSERT(c_p);
     ASSERT(sproc->common.id == c_p->common.id);
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p)
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p)
 		       & ERTS_PROC_LOCK_MAIN);
 
     sproc->htop = c_p->htop;
@@ -311,7 +308,7 @@ erts_make_dirty_shadow_proc(ErtsSchedulerData *esdp, Process *c_p)
     sproc = esdp->dirty_shadow_process;
     ASSERT(sproc);
     ASSERT(sproc->static_flags & ERTS_STC_FLG_SHADOW_PROC);
-    ASSERT(erts_smp_atomic32_read_nob(&sproc->state)
+    ASSERT(erts_atomic32_read_nob(&sproc->state)
 	   == (ERTS_PSFLG_ACTIVE
 	       | ERTS_PSFLG_DIRTY_RUNNING
 	       | ERTS_PSFLG_PROXY));
@@ -326,7 +323,6 @@ erts_make_dirty_shadow_proc(ErtsSchedulerData *esdp, Process *c_p)
 
 #endif /* ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
-#endif /* ERTS_DIRTY_SCHEDULERS */
 
 #endif /* defined(ERTS_WANT_NFUNC_SCHED_INTERNALS__) && !defined(ERTS_NFUNC_SCHED_INTERNALS__) */
 
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index f67b67325d..0a5fe026db 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -138,7 +138,7 @@ execution_state(ErlNifEnv *env, Process **c_pp, int *schedp)
 	    Process *c_p = env->proc;
 
 	    if (!(c_p->static_flags & ERTS_STC_FLG_SHADOW_PROC)) {
-		ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p)
+		ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p)
 				   & ERTS_PROC_LOCK_MAIN);
 	    }
 	    else {
@@ -220,7 +220,7 @@ void erts_pre_nif(ErlNifEnv* env, Process* p, struct erl_module_nif* mod_nif,
 	ASSERT(esdp);
 
 	if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
-	    erts_aint32_t state = erts_smp_atomic32_read_nob(&p->state);
+	    erts_aint32_t state = erts_atomic32_read_nob(&p->state);
 
 	    ASSERT(p->scheduler_data == esdp);
 	    ASSERT((state & (ERTS_PSFLG_RUNNING
@@ -287,12 +287,12 @@ schedule(ErlNifEnv* env, NativeFunPtr direct_fp, NativeFunPtr indirect_fp,
     else
 	dirty_shadow_proc = env->proc;
 
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(c_p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(c_p));
 
     ep = erts_nif_export_schedule(c_p, dirty_shadow_proc,
 				  c_p->current,
 				  c_p->cp,
-				  (BeamInstr) em_call_nif,
+				  BeamOpCodeAddr(op_call_nif),
 				  direct_fp, indirect_fp,
 				  mod, func_name,
 				  argc, (const Eterm *) argv);
@@ -304,7 +304,6 @@ schedule(ErlNifEnv* env, NativeFunPtr direct_fp, NativeFunPtr indirect_fp,
     return (ERL_NIF_TERM) THE_NON_VALUE;
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 static ERL_NIF_TERM dirty_nif_finalizer(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]);
 static ERL_NIF_TERM dirty_nif_exception(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]);
@@ -320,7 +319,7 @@ erts_call_dirty_nif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
     ErlNifEnv env;
     ERL_NIF_TERM result;
 #ifdef DEBUG
-    erts_aint32_t state = erts_smp_atomic32_read_nob(&c_p->state);
+    erts_aint32_t state = erts_atomic32_read_nob(&c_p->state);
 
     ASSERT(nep == ERTS_PROC_GET_NIF_TRAP_EXPORT(c_p));
 
@@ -343,14 +342,14 @@ erts_call_dirty_nif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
 
     ASSERT(ERTS_SCHEDULER_IS_DIRTY(erts_proc_sched_data(c_p)));
 
-    erts_smp_atomic32_read_band_mb(&c_p->state, ~(ERTS_PSFLG_DIRTY_CPU_PROC
+    erts_atomic32_read_band_mb(&c_p->state, ~(ERTS_PSFLG_DIRTY_CPU_PROC
 						   | ERTS_PSFLG_DIRTY_IO_PROC));
 
-    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+    erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
 
     result = (*dirty_nif)(&env, codemfa->arity, argv); /* Call dirty NIF */
 
-    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+    erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
 
     ASSERT(env.proc->static_flags & ERTS_STC_FLG_SHADOW_PROC);
     ASSERT(env.proc->next == c_p);
@@ -394,24 +393,19 @@ erts_call_dirty_nif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
     return exiting;
 }
 
-#endif
 
 static void full_flush_env(ErlNifEnv* env)
 {
     flush_env(env);
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (env->proc->static_flags & ERTS_STC_FLG_SHADOW_PROC)
 	/* Dirty nif call using shadow process struct */
 	erts_flush_dirty_shadow_proc(env->proc);
-#endif
 }
 
 static void full_cache_env(ErlNifEnv* env)
 {    
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (env->proc->static_flags & ERTS_STC_FLG_SHADOW_PROC)
 	erts_cache_dirty_shadow_proc(env->proc);
-#endif
     cache_env(env);
 }
 
@@ -566,10 +560,9 @@ void enif_clear_env(ErlNifEnv* env)
     ASSERT(!is_offheap(&MSO(p)));
 }
 
-#ifdef ERTS_SMP
 #ifdef DEBUG
 static int enif_send_delay = 0;
-#define ERTS_FORCE_ENIF_SEND_DELAY() (enif_send_delay++ % 2 == 0)
+#define ERTS_FORCE_ENIF_SEND_DELAY() (enif_send_delay++ % 32 == 0)
 #else
 #ifdef ERTS_PROC_LOCK_OWN_IMPL
 #define ERTS_FORCE_ENIF_SEND_DELAY() 0
@@ -592,9 +585,9 @@ int erts_flush_trace_messages(Process *c_p, ErtsProcLocks c_p_locks)
 
     /* Only one thread at a time is allowed to flush trace messages,
        so we require the main lock to be held when doing the flush */
-    ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(c_p);
+    ERTS_CHK_HAVE_ONLY_MAIN_PROC_LOCK(c_p);
 
-    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_TRACE);
+    erts_proc_lock(c_p, ERTS_PROC_LOCK_TRACE);
 
     msgq = c_p->trace_msg_q;
 
@@ -613,7 +606,7 @@ int erts_flush_trace_messages(Process *c_p, ErtsProcLocks c_p_locks)
         msgq->first = NULL;
         msgq->last = &msgq->first;
         msgq->len = 0;
-        erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_TRACE);
+        erts_proc_unlock(c_p, ERTS_PROC_LOCK_TRACE);
 
         ASSERT(len != 0);
 
@@ -626,13 +619,13 @@ int erts_flush_trace_messages(Process *c_p, ErtsProcLocks c_p_locks)
             if (rp->common.id == c_p->common.id)
                 rp_locks &= ~c_p_locks;
             if (rp_locks)
-                erts_smp_proc_unlock(rp, rp_locks);
+                erts_proc_unlock(rp, rp_locks);
             reds += len;
         } else {
             erts_cleanup_messages(first);
         }
         reds += 1;
-        erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_TRACE);
+        erts_proc_lock(c_p, ERTS_PROC_LOCK_TRACE);
         msgq = msgq->next;
     } while (msgq);
 
@@ -649,21 +642,18 @@ int erts_flush_trace_messages(Process *c_p, ErtsProcLocks c_p_locks)
     }
 
 error:
-    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_TRACE);
+    erts_proc_unlock(c_p, ERTS_PROC_LOCK_TRACE);
 
     return reds;
 }
 
-#endif
 
 int enif_send(ErlNifEnv* env, const ErlNifPid* to_pid,
 	      ErlNifEnv* msg_env, ERL_NIF_TERM msg)
 {
     struct enif_msg_environment_t* menv = (struct enif_msg_environment_t*)msg_env;
     ErtsProcLocks rp_locks = 0;
-#ifdef ERTS_SMP
     ErtsProcLocks lc_locks = 0;
-#endif
     Process* rp;
     Process* c_p;
     ErtsMessage *mp;
@@ -672,13 +662,6 @@ int enif_send(ErlNifEnv* env, const ErlNifPid* to_pid,
 
     execution_state(env, &c_p, &scheduler);
 
-#ifndef ERTS_SMP
-    if (!scheduler) {
-	erts_exit(ERTS_ABORT_EXIT,
-		  "enif_send: called from non-scheduler thread on non-SMP VM");
-	return 0;
-   }
-#endif
 
     if (scheduler > 0) { /* Normal scheduler */
 	rp = erts_proc_lookup(receiver);
@@ -692,7 +675,7 @@ int enif_send(ErlNifEnv* env, const ErlNifPid* to_pid,
 		return 0;
 
 	    if (env->proc->static_flags & ERTS_STC_FLG_SHADOW_PROC) {
-		erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+		erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
 	    }
 	}
 
@@ -701,7 +684,7 @@ int enif_send(ErlNifEnv* env, const ErlNifPid* to_pid,
 			       ERTS_P2P_FLG_INC_REFC);
 	if (!rp) {
 	    if (c_p && (env->proc->static_flags & ERTS_STC_FLG_SHADOW_PROC))
-		erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+		erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
 	    return 0;
 	}
     }
@@ -736,7 +719,7 @@ int enif_send(ErlNifEnv* env, const ErlNifPid* to_pid,
 	    full_cache_env(env);
 	}
 	else {
-	    erts_aint_t state = erts_smp_atomic32_read_nob(&rp->state);
+	    erts_aint_t state = erts_atomic32_read_nob(&rp->state);
 	    if (state & ERTS_PSFLG_OFF_HEAP_MSGQ) {
 		mp = erts_alloc_message(sz, &hp);
 		ohp = sz == 0 ? NULL : &mp->hfrag.off_heap;
@@ -762,7 +745,6 @@ int enif_send(ErlNifEnv* env, const ErlNifPid* to_pid,
 	    full_cache_env(env);
 	}
     }
-#ifdef ERTS_SMP
     else {
         /* This clause is taken when the nif is called in the context
            of a traced process. We do not know which locks we have
@@ -773,7 +755,7 @@ int enif_send(ErlNifEnv* env, const ErlNifPid* to_pid,
         Process *t_p = env->tracee;
 
 
-        erts_smp_proc_lock(t_p, ERTS_PROC_LOCK_TRACE);
+        erts_proc_lock(t_p, ERTS_PROC_LOCK_TRACE);
 
         msgq = t_p->trace_msg_q;
 
@@ -790,7 +772,7 @@ int enif_send(ErlNifEnv* env, const ErlNifPid* to_pid,
 #endif
         if (ERTS_FORCE_ENIF_SEND_DELAY() || msgq ||
             rp_locks & ERTS_PROC_LOCK_MSGQ ||
-            erts_smp_proc_trylock(rp, ERTS_PROC_LOCK_MSGQ) == EBUSY) {
+            erts_proc_trylock(rp, ERTS_PROC_LOCK_MSGQ) == EBUSY) {
 
             if (!msgq) {
                 msgq = erts_alloc(ERTS_ALC_T_TRACE_MSG_QUEUE,
@@ -804,36 +786,33 @@ int enif_send(ErlNifEnv* env, const ErlNifPid* to_pid,
                 msgq->next = t_p->trace_msg_q;
                 t_p->trace_msg_q = msgq;
 
-                erts_smp_proc_unlock(t_p, ERTS_PROC_LOCK_TRACE);
+                erts_proc_unlock(t_p, ERTS_PROC_LOCK_TRACE);
 
 		erts_schedule_flush_trace_messages(t_p, 0);
             } else {
                 msgq->len++;
                 *msgq->last = mp;
                 msgq->last = &mp->next;
-                erts_smp_proc_unlock(t_p, ERTS_PROC_LOCK_TRACE);
+                erts_proc_unlock(t_p, ERTS_PROC_LOCK_TRACE);
             }
             goto done;
         } else {
-            erts_smp_proc_unlock(t_p, ERTS_PROC_LOCK_TRACE);
+            erts_proc_unlock(t_p, ERTS_PROC_LOCK_TRACE);
             rp_locks &= ~ERTS_PROC_LOCK_TRACE;
             rp_locks |= ERTS_PROC_LOCK_MSGQ;
         }
     }
-#endif /* ERTS_SMP */
 
     erts_queue_message(rp, rp_locks, mp, msg,
                        c_p ? c_p->common.id : am_undefined);
 
-#ifdef ERTS_SMP
 done:
     if (c_p == rp)
 	rp_locks &= ~ERTS_PROC_LOCK_MAIN;
     if (rp_locks & ~lc_locks)
-	erts_smp_proc_unlock(rp, rp_locks & ~lc_locks);
+	erts_proc_unlock(rp, rp_locks & ~lc_locks);
     if (c_p && (env->proc->static_flags & ERTS_STC_FLG_SHADOW_PROC))
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
-#endif
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
     if (scheduler <= 0)
 	erts_proc_dec_refc(rp);
 
@@ -863,15 +842,9 @@ enif_port_command(ErlNifEnv *env, const ErlNifPort* to_port,
     if (scheduler > 0)
 	prt = erts_port_lookup(to_port->port_id, iflags);
     else {
-#ifdef ERTS_SMP
 	if (ERTS_PROC_IS_EXITING(c_p))
 	    return 0;
 	prt = erts_thr_port_lookup(to_port->port_id, iflags);
-#else
-        erts_exit(ERTS_ABORT_EXIT,
-		  "enif_port_command: called from non-scheduler "
-                  "thread on non-SMP VM");
-#endif
     }
 
     if (!prt)
@@ -1230,11 +1203,12 @@ size_t enif_binary_to_term(ErlNifEnv *dst_env,
     Sint size;
     ErtsHeapFactory factory;
     byte *bp = (byte*) data;
+    Uint32 flags = 0;
 
-    ERTS_CT_ASSERT(ERL_NIF_BIN2TERM_SAFE == ERTS_DIST_EXT_BTT_SAFE);
-
-    if (opts & ~ERL_NIF_BIN2TERM_SAFE) {
-        return 0;
+    switch ((Uint32)opts) {
+    case 0: break;
+    case ERL_NIF_BIN2TERM_SAFE: flags = ERTS_DIST_EXT_BTT_SAFE; break;
+    default: return 0;
     }
     if ((size = erts_decode_ext_size(bp, data_sz)) < 0)
         return 0;
@@ -1246,7 +1220,7 @@ size_t enif_binary_to_term(ErlNifEnv *dst_env,
         erts_factory_dummy_init(&factory);
     }
 
-    *term = erts_decode_ext(&factory, &bp, (Uint32)opts);
+    *term = erts_decode_ext(&factory, &bp, flags);
 
     if (is_non_value(*term)) {
         return 0;
@@ -1854,18 +1828,11 @@ int enif_is_process_alive(ErlNifEnv* env, ErlNifPid *proc)
     if (scheduler > 0)
 	return !!erts_proc_lookup(proc->pid);
     else {
-#ifdef ERTS_SMP
 	Process* rp = erts_pid2proc_opt(NULL, 0, proc->pid, 0,
 					ERTS_P2P_FLG_INC_REFC);
 	if (rp)
 	    erts_proc_dec_refc(rp);
 	return !!rp;
-#else
-	erts_exit(ERTS_ABORT_EXIT, "enif_is_process_alive: "
-		  "called from non-scheduler thread "
-                  "in non-smp emulator");
-	return 0;
-#endif
     }
 }
 
@@ -1881,17 +1848,10 @@ int enif_is_port_alive(ErlNifEnv *env, ErlNifPort *port)
     if (scheduler > 0)
 	return !!erts_port_lookup(port->port_id, iflags);
     else {
-#ifdef ERTS_SMP
 	Port *prt = erts_thr_port_lookup(port->port_id, iflags);
 	if (prt)
 	    erts_port_dec_refc(prt);
 	return !!prt;
-#else
-	erts_exit(ERTS_ABORT_EXIT, "enif_is_port_alive: "
-		  "called from non-scheduler thread "
-                  "in non-smp emulator");
-	return 0;
-#endif
     }
 }
 
@@ -2099,7 +2059,7 @@ ErlNifResourceType* open_resource_type(ErlNifEnv* env,
     ErlNifResourceFlags op = flags;
     Eterm module_am, name_am;
 
-    ASSERT(erts_smp_thr_progress_is_blocking());
+    ASSERT(erts_thr_progress_is_blocking());
     module_am = make_atom(env->mod_nif->mod->module);
     name_am = enif_make_atom(env, name_str);
 
@@ -2238,19 +2198,14 @@ static void destroy_one_monitor(ErtsMonitor* mon, void* context)
         rp = erts_proc_lookup(mon->u.pid);
     }
     else {
-#ifdef ERTS_SMP
         rp = erts_proc_lookup_inc_refc(mon->u.pid);
-#else
-        ASSERT(!"nif monitor destruction in non-scheduler thread");
-        rp = NULL;
-#endif
     }
 
     if (!rp) {
         is_exiting = 1;
     }
     if (rp) {
-        erts_smp_proc_lock(rp, ERTS_PROC_LOCK_LINK);
+        erts_proc_lock(rp, ERTS_PROC_LOCK_LINK);
         if (ERTS_PROC_IS_EXITING(rp)) {
             is_exiting = 1;
         } else {
@@ -2258,11 +2213,9 @@ static void destroy_one_monitor(ErtsMonitor* mon, void* context)
             ASSERT(rmon);
             is_exiting = 0;
         }
-        erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
-#ifdef ERTS_SMP
+        erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
         if (ctx->scheduler <= 0)
             erts_proc_dec_refc(rp);
-#endif
     }
     if (is_exiting) {
         ctx->resource->monitors->pending_failed_fire++;
@@ -2288,34 +2241,7 @@ static void destroy_all_monitors(ErtsMonitor* monitors, ErtsResource* resource)
 }
 
 
-#ifdef ERTS_SMP
 #  define NIF_RESOURCE_DTOR &nif_resource_dtor
-#else
-#  define NIF_RESOURCE_DTOR &nosmp_nif_resource_dtor_prologue
-
-/*
- * NO-SMP: Always run resource destructor on scheduler thread 
- *         as we may have to remove process monitors.
- */
-static int nif_resource_dtor(Binary*);
-
-static void nosmp_nif_resource_dtor_scheduled(void* vbin)
-{
-    erts_bin_free((Binary*)vbin);
-}
-
-static int nosmp_nif_resource_dtor_prologue(Binary* bin)
-{
-    if (is_scheduler()) {
-        return nif_resource_dtor(bin);
-    }
-    else {
-        erts_schedule_misc_aux_work(1, nosmp_nif_resource_dtor_scheduled, bin);
-        return 0; /* do not free */
-    }
-}
-
-#endif /* !ERTS_SMP */
 
 static int nif_resource_dtor(Binary* bin)
 {
@@ -2327,7 +2253,7 @@ static int nif_resource_dtor(Binary* bin)
         ErtsResourceMonitors* rm = resource->monitors;
 
         ASSERT(type->down);
-        erts_smp_mtx_lock(&rm->lock);
+        erts_mtx_lock(&rm->lock);
         ASSERT(erts_refc_read(&bin->intern.refc, 0) == 0);
         if (rm->root) {
             ASSERT(!rm->is_dying);
@@ -2349,11 +2275,11 @@ static int nif_resource_dtor(Binary* bin)
              */
             ASSERT(!rm->is_dying);
             rm->is_dying = 1;
-            erts_smp_mtx_unlock(&rm->lock);
+            erts_mtx_unlock(&rm->lock);
             return 0;
         }
-        erts_smp_mtx_unlock(&rm->lock);
-        erts_smp_mtx_destroy(&rm->lock);
+        erts_mtx_unlock(&rm->lock);
+        erts_mtx_destroy(&rm->lock);
     }
 
     if (type->dtor != NULL) {
@@ -2394,12 +2320,12 @@ void erts_fire_nif_monitor(ErtsResource* resource, Eterm pid, Eterm ref)
     ASSERT(rmp);
     ASSERT(resource->type->down);
 
-    erts_smp_mtx_lock(&rmp->lock);
+    erts_mtx_lock(&rmp->lock);
     rmon = erts_remove_monitor(&rmp->root, ref);
     if (!rmon) {
         int free_me = (--rmp->pending_failed_fire == 0) && rmp->is_dying;
         ASSERT(rmp->pending_failed_fire >= 0);
-        erts_smp_mtx_unlock(&rmp->lock);
+        erts_mtx_unlock(&rmp->lock);
 
         if (free_me) {
             ASSERT(erts_refc_read(&bin->binary.intern.refc, 0) == 0);
@@ -2415,10 +2341,10 @@ void erts_fire_nif_monitor(ErtsResource* resource, Eterm pid, Eterm ref)
          * we avoid calling 'down' and just silently remove the monitor.
          * This can happen even for non smp as destructor calls may be scheduled.
          */
-        erts_smp_mtx_unlock(&rmp->lock);
+        erts_mtx_unlock(&rmp->lock);
     }
     else {
-        erts_smp_mtx_unlock(&rmp->lock);
+        erts_mtx_unlock(&rmp->lock);
 
         ASSERT(rmon->u.pid == pid);
         erts_ref_to_driver_monitor(ref, &nif_monitor);
@@ -2463,7 +2389,7 @@ void* enif_alloc_resource(ErlNifResourceType* type, size_t data_sz)
     erts_refc_inc(&resource->type->refc, 2);
     if (type->down) {
         resource->monitors = (ErtsResourceMonitors*) (resource->data + monitors_offs);
-        erts_smp_mtx_init(&resource->monitors->lock, "resource_monitors", NIL,
+        erts_mtx_init(&resource->monitors->lock, "resource_monitors", NIL,
             ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
         resource->monitors->root = NULL;
         resource->monitors->pending_failed_fire = 0;
@@ -2662,7 +2588,6 @@ nif_export_restore(Process *c_p, NifExport *ep, Eterm res)
 }
 
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 /*
  * Finalize a dirty NIF call. This function is scheduled to cause the VM to
@@ -2732,7 +2657,7 @@ schedule_dirty_nif(ErlNifEnv* env, int flags, NativeFunPtr fp,
 
     execution_state(env, &proc, NULL);
 
-    (void) erts_smp_atomic32_read_bset_nob(&proc->state,
+    (void) erts_atomic32_read_bset_nob(&proc->state,
 					   (ERTS_PSFLG_DIRTY_CPU_PROC
 					    | ERTS_PSFLG_DIRTY_IO_PROC),
 					   (flags == ERL_NIF_DIRTY_JOB_CPU_BOUND
@@ -2770,7 +2695,7 @@ static_schedule_dirty_nif(ErlNifEnv* env, erts_aint32_t dirty_psflg,
     ASSERT(is_atom(mod) && is_atom(func));
     ASSERT(fp);
 
-    (void) erts_smp_atomic32_read_bset_nob(&proc->state,
+    (void) erts_atomic32_read_bset_nob(&proc->state,
 					   (ERTS_PSFLG_DIRTY_CPU_PROC
 					    | ERTS_PSFLG_DIRTY_IO_PROC),
 					   dirty_psflg);
@@ -2790,7 +2715,6 @@ static_schedule_dirty_cpu_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[
     return static_schedule_dirty_nif(env, ERTS_PSFLG_DIRTY_CPU_PROC, argc, argv);
 }
 
-#endif /* ERTS_DIRTY_SCHEDULERS */
 
 /*
  * NIF execution wrapper used by enif_schedule_nif() for regular NIFs. It
@@ -2864,24 +2788,20 @@ enif_schedule_nif(ErlNifEnv* env, const char* fun_name, int flags,
     if (scheduler <= 0) {
 	if (scheduler == 0)
 	    enif_make_badarg(env);
-	erts_smp_proc_lock(proc, ERTS_PROC_LOCK_MAIN);
+	erts_proc_lock(proc, ERTS_PROC_LOCK_MAIN);
     }
 
     if (flags == 0)
 	result = schedule(env, execute_nif, fp, proc->current->module,
 			  fun_name_atom, argc, argv);
     else if (!(flags & ~(ERL_NIF_DIRTY_JOB_IO_BOUND|ERL_NIF_DIRTY_JOB_CPU_BOUND))) {
-#ifdef ERTS_DIRTY_SCHEDULERS
 	result = schedule_dirty_nif(env, flags, fp, fun_name_atom, argc, argv);
-#else
-        result = enif_raise_exception(env, am_notsup);
-#endif
     }
     else
 	result = enif_make_badarg(env);
 
     if (scheduler < 0)
-	erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
 
     return result;
 }
@@ -2897,12 +2817,10 @@ enif_thread_type(void)
     switch (esdp->type) {
     case ERTS_SCHED_NORMAL:
 	return ERL_NIF_THR_NORMAL_SCHEDULER;
-#ifdef ERTS_DIRTY_SCHEDULERS
     case ERTS_SCHED_DIRTY_CPU:
 	return ERL_NIF_THR_DIRTY_CPU_SCHEDULER;
     case ERTS_SCHED_DIRTY_IO:
         return ERL_NIF_THR_DIRTY_IO_SCHEDULER;
-#endif
     default:
         ERTS_INTERNAL_ERROR("Invalid scheduler type");
 	return -1;
@@ -3223,27 +3141,19 @@ int enif_monitor_process(ErlNifEnv* env, void* obj, const ErlNifPid* target_pid,
 
     execution_state(env, NULL, &scheduler);
 
-#ifdef ERTS_SMP
     if (scheduler > 0) /* Normal scheduler */
         rp = erts_proc_lookup_raw(target_pid->pid);
     else
         rp = erts_proc_lookup_raw_inc_refc(target_pid->pid);
-#else
-    if (scheduler <= 0) {
-        erts_exit(ERTS_ABORT_EXIT, "enif_monitor_process: called from "
-                  "non-scheduler thread on non-SMP VM");
-    }
-    rp = erts_proc_lookup(target_pid->pid);
-#endif
 
     if (!rp)
         return 1;
 
     ref = erts_make_ref_in_buffer(tmp);
 
-    erts_smp_mtx_lock(&rsrc->monitors->lock);
-    erts_smp_proc_lock(rp, ERTS_PROC_LOCK_LINK);
-    if (ERTS_PSFLG_FREE & erts_smp_atomic32_read_nob(&rp->state)) {
+    erts_mtx_lock(&rsrc->monitors->lock);
+    erts_proc_lock(rp, ERTS_PROC_LOCK_LINK);
+    if (ERTS_PSFLG_FREE & erts_atomic32_read_nob(&rp->state)) {
         retval = 1;
     }
     else {
@@ -3251,13 +3161,11 @@ int enif_monitor_process(ErlNifEnv* env, void* obj, const ErlNifPid* target_pid,
         erts_add_monitor(&ERTS_P_MONITORS(rp), MON_NIF_TARGET, ref, (UWord)rsrc, NIL);
         retval = 0;
     }
-    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
-    erts_smp_mtx_unlock(&rsrc->monitors->lock);
+    erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+    erts_mtx_unlock(&rsrc->monitors->lock);
 
-#ifdef ERTS_SMP
     if (scheduler <= 0)
         erts_proc_dec_refc(rp);
-#endif
     if (monitor)
         erts_ref_to_driver_monitor(ref,monitor);
 
@@ -3285,35 +3193,27 @@ int enif_demonitor_process(ErlNifEnv* env, void* obj, const ErlNifMonitor* monit
 
     ref = erts_driver_monitor_to_ref(ref_heap, monitor);
 
-    erts_smp_mtx_lock(&rsrc->monitors->lock);
+    erts_mtx_lock(&rsrc->monitors->lock);
     mon = erts_remove_monitor(&rsrc->monitors->root, ref);
 
     if (mon == NULL) {
-        erts_smp_mtx_unlock(&rsrc->monitors->lock);
+        erts_mtx_unlock(&rsrc->monitors->lock);
         return 1;
     }
 
     ASSERT(mon->type == MON_ORIGIN);
     ASSERT(is_internal_pid(mon->u.pid));
 
-#ifdef ERTS_SMP
     if (scheduler > 0) /* Normal scheduler */
         rp = erts_proc_lookup(mon->u.pid);
     else
         rp = erts_proc_lookup_inc_refc(mon->u.pid);
-#else
-    if (scheduler <= 0) {
-        erts_exit(ERTS_ABORT_EXIT, "enif_demonitor_process: called from "
-                  "non-scheduler thread on non-SMP VM");
-    }
-    rp = erts_proc_lookup(mon->u.pid);
-#endif
 
     if (!rp) {
         is_exiting = 1;
     }
     else {
-        erts_smp_proc_lock(rp, ERTS_PROC_LOCK_LINK);
+        erts_proc_lock(rp, ERTS_PROC_LOCK_LINK);
         if (ERTS_PROC_IS_EXITING(rp)) {
             is_exiting = 1;
         } else {
@@ -3321,17 +3221,15 @@ int enif_demonitor_process(ErlNifEnv* env, void* obj, const ErlNifMonitor* monit
             ASSERT(rmon);
             is_exiting = 0;
         }
-        erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+        erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 
-#ifdef ERTS_SMP
         if (scheduler <= 0)
             erts_proc_dec_refc(rp);
-#endif
     }
     if (is_exiting) {
         rsrc->monitors->pending_failed_fire++;
     }
-    erts_smp_mtx_unlock(&rsrc->monitors->lock);
+    erts_mtx_unlock(&rsrc->monitors->lock);
 
     if (rmon) {
         ASSERT(rmon->type == MON_NIF_TARGET);
@@ -3707,6 +3605,55 @@ int enif_ioq_deq(ErlNifIOQueue *q, size_t elems, size_t *size)
     return 1;
 }
 
+int enif_ioq_peek_head(ErlNifEnv *env, ErlNifIOQueue *q, size_t *size, ERL_NIF_TERM *bin_term) {
+    SysIOVec *iov_entry;
+    Binary *ref_bin;
+
+    if (q->size == 0) {
+        return 0;
+    }
+
+    ASSERT(q->b_head != q->b_tail && q->v_head != q->v_tail);
+
+    ref_bin = &q->b_head[0]->nif;
+    iov_entry = &q->v_head[0];
+
+    if (size != NULL) {
+        *size = iov_entry->iov_len;
+    }
+
+    if (iov_entry->iov_len > ERL_ONHEAP_BIN_LIMIT) {
+        ProcBin *pb = (ProcBin*)alloc_heap(env, PROC_BIN_SIZE);
+
+        pb->thing_word = HEADER_PROC_BIN;
+        pb->next = MSO(env->proc).first;
+        pb->val = ref_bin;
+        pb->flags = 0;
+
+        ASSERT((byte*)iov_entry->iov_base >= (byte*)ref_bin->orig_bytes);
+        ASSERT(iov_entry->iov_len <= ref_bin->orig_size);
+
+        pb->bytes = (byte*)iov_entry->iov_base;
+        pb->size = iov_entry->iov_len;
+
+        MSO(env->proc).first = (struct erl_off_heap_header*) pb;
+        OH_OVERHEAD(&(MSO(env->proc)), pb->size / sizeof(Eterm));
+
+        erts_refc_inc(&ref_bin->intern.refc, 2);
+        *bin_term = make_binary(pb);
+    } else {
+        ErlHeapBin* hb = (ErlHeapBin*)alloc_heap(env, heap_bin_size(iov_entry->iov_len));
+
+        hb->thing_word = header_heap_bin(iov_entry->iov_len);
+        hb->size = iov_entry->iov_len;
+
+        sys_memcpy(hb->data, iov_entry->iov_base, iov_entry->iov_len);
+        *bin_term = make_binary(hb);
+    }
+
+    return 1;
+}
+
 SysIOVec *enif_ioq_peek(ErlNifIOQueue *q, int *iovlen)
 {
     return erts_ioq_peekq(q, iovlen);
@@ -3723,7 +3670,7 @@ static ErtsCodeInfo** get_func_pp(BeamCodeHeader* mod_code, Eterm f_atom, unsign
     int j;
     for (j = 0; j < n; ++j) {
 	ErtsCodeInfo* ci = mod_code->functions[j];
-	ASSERT(ci->op == (BeamInstr) BeamOp(op_i_func_info_IaaI));
+	ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
 	if (f_atom == ci->mfa.function
 	    && arity == ci->mfa.arity) {
 	    return mod_code->functions+j;
@@ -3919,8 +3866,8 @@ BIF_RETTYPE load_nif_2(BIF_ALIST_2)
     }
 
     /* Block system (is this the right place to do it?) */
-    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-    erts_smp_thr_progress_block();
+    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    erts_thr_progress_block();
 
     /* Find calling module */
     ASSERT(BIF_P->current != NULL);
@@ -4025,14 +3972,9 @@ BIF_RETTYPE load_nif_2(BIF_ALIST_2)
 		 * dirty scheduler support, treat a non-zero flags field as
 		 * a load error.
 		 */
-#ifdef ERTS_DIRTY_SCHEDULERS
 		if (f->flags != ERL_NIF_DIRTY_JOB_IO_BOUND && f->flags != ERL_NIF_DIRTY_JOB_CPU_BOUND)
 		    ret = load_nif_error(BIF_P, bad_lib, "Illegal flags field value %d for NIF %T:%s/%u",
 					 f->flags, mod_atom, f->name, f->arity);
-#else
-		ret = load_nif_error(BIF_P, bad_lib, "NIF %T:%s/%u requires a runtime with dirty scheduler support.",
-				     mod_atom, f->name, f->arity);
-#endif
 	    }
 	    else if (erts_codeinfo_to_code(ci_pp[1]) - erts_codeinfo_to_code(ci_pp[0])
                      < BEAM_NIF_MIN_FUNC_SZ)
@@ -4097,15 +4039,13 @@ BIF_RETTYPE load_nif_2(BIF_ALIST_2)
             code_ptr = erts_codeinfo_to_code(ci);
 
 	    if (ci->u.gen_bp == NULL) {
-		code_ptr[0] = (BeamInstr) BeamOp(op_call_nif);
+		code_ptr[0] = BeamOpCodeAddr(op_call_nif);
 	    }
 	    else { /* Function traced, patch the original instruction word */
 		GenericBp* g = ci->u.gen_bp;
-		ASSERT(code_ptr[0] ==
-		       (BeamInstr) BeamOp(op_i_generic_breakpoint));
-		g->orig_instr = (BeamInstr) BeamOp(op_call_nif);
+		ASSERT(BeamIsOpCode(code_ptr[0], op_i_generic_breakpoint));
+		g->orig_instr = BeamOpCodeAddr(op_call_nif);
 	    }
-#ifdef ERTS_DIRTY_SCHEDULERS
 	    if (f->flags) {
 		code_ptr[3] = (BeamInstr) f->fptr;
 		code_ptr[1] = (f->flags == ERL_NIF_DIRTY_JOB_IO_BOUND) ?
@@ -4113,7 +4053,6 @@ BIF_RETTYPE load_nif_2(BIF_ALIST_2)
 		    (BeamInstr) static_schedule_dirty_cpu_nif;
 	    }
 	    else
-#endif
 		code_ptr[1] = (BeamInstr) f->fptr;
 	    code_ptr[2] = (BeamInstr) lib;
 	}
@@ -4131,8 +4070,8 @@ BIF_RETTYPE load_nif_2(BIF_ALIST_2)
 	erts_sys_ddll_free_error(&errdesc);
     }
 
-    erts_smp_thr_progress_unblock();
-    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+    erts_thr_progress_unblock();
+    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
     erts_release_code_write_permission();
     erts_free(ERTS_ALC_T_TMP, lib_name);
 
@@ -4145,7 +4084,7 @@ erts_unload_nif(struct erl_module_nif* lib)
 {
     ErlNifResourceType* rt;
     ErlNifResourceType* next;
-    ASSERT(erts_smp_thr_progress_is_blocking());
+    ASSERT(erts_thr_progress_is_blocking());
     ASSERT(lib != NULL);
     ASSERT(lib->mod != NULL);
 
@@ -4217,8 +4156,8 @@ Eterm erts_nif_call_function(Process *p, Process *tracee,
             break;
     ASSERT(i < mod->entry.num_of_funcs);
     if (p)
-        ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(p) & ERTS_PROC_LOCK_MAIN
-                           || erts_smp_thr_progress_is_blocking());
+        ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(p) & ERTS_PROC_LOCK_MAIN
+                           || erts_thr_progress_is_blocking());
 #endif
     if (p) {
         /* This is almost a normal nif call like in beam_emu,
diff --git a/erts/emulator/beam/erl_nif.h b/erts/emulator/beam/erl_nif.h
index 7fb447e4a8..053f7673c4 100644
--- a/erts/emulator/beam/erl_nif.h
+++ b/erts/emulator/beam/erl_nif.h
@@ -52,9 +52,10 @@
 ** 2.11: 19.0 enif_snprintf 
 ** 2.12: 20.0 add enif_select, enif_open_resource_type_x
 ** 2.13: 20.1 add enif_ioq
+** 2.14: 21.0 add enif_ioq_peek_head
 */
 #define ERL_NIF_MAJOR_VERSION 2
-#define ERL_NIF_MINOR_VERSION 13
+#define ERL_NIF_MINOR_VERSION 14
 
 /*
  * The emulator will refuse to load a nif-lib with a major version
diff --git a/erts/emulator/beam/erl_nif_api_funcs.h b/erts/emulator/beam/erl_nif_api_funcs.h
index 9e573307d8..3750fd9b68 100644
--- a/erts/emulator/beam/erl_nif_api_funcs.h
+++ b/erts/emulator/beam/erl_nif_api_funcs.h
@@ -198,6 +198,7 @@ ERL_NIF_API_FUNC_DECL(SysIOVec*,enif_ioq_peek,(ErlNifIOQueue *q, int *iovlen));
 ERL_NIF_API_FUNC_DECL(int,enif_inspect_iovec,(ErlNifEnv *env, size_t max_length, ERL_NIF_TERM iovec_term, ERL_NIF_TERM *tail, ErlNifIOVec **iovec));
 ERL_NIF_API_FUNC_DECL(void,enif_free_iovec,(ErlNifIOVec *iov));
 
+ERL_NIF_API_FUNC_DECL(int,enif_ioq_peek_head,(ErlNifEnv *env, ErlNifIOQueue *q, size_t *size, ERL_NIF_TERM *head));
 
 /*
 ** ADD NEW ENTRIES HERE (before this comment) !!!
@@ -373,6 +374,7 @@ ERL_NIF_API_FUNC_DECL(void,enif_free_iovec,(ErlNifIOVec *iov));
 #  define enif_ioq_peek ERL_NIF_API_FUNC_MACRO(enif_ioq_peek)
 #  define enif_inspect_iovec ERL_NIF_API_FUNC_MACRO(enif_inspect_iovec)
 #  define enif_free_iovec ERL_NIF_API_FUNC_MACRO(enif_free_iovec)
+#  define enif_ioq_peek_head ERL_NIF_API_FUNC_MACRO(enif_ioq_peek_head)
 
 /*
 ** ADD NEW ENTRIES HERE (before this comment)
diff --git a/erts/emulator/beam/erl_node_tables.c b/erts/emulator/beam/erl_node_tables.c
index deadf435e9..eaf133f5c0 100644
--- a/erts/emulator/beam/erl_node_tables.c
+++ b/erts/emulator/beam/erl_node_tables.c
@@ -29,17 +29,21 @@
 #include "error.h"
 #include "erl_thr_progress.h"
 #include "dtrace-wrapper.h"
+#include "erl_binary.h"
+#include "erl_bif_unique.h"
 
 Hash erts_dist_table;
 Hash erts_node_table;
-erts_smp_rwmtx_t erts_dist_table_rwmtx;
-erts_smp_rwmtx_t erts_node_table_rwmtx;
+erts_rwmtx_t erts_dist_table_rwmtx;
+erts_rwmtx_t erts_node_table_rwmtx;
 
 DistEntry *erts_hidden_dist_entries;
 DistEntry *erts_visible_dist_entries;
+DistEntry *erts_pending_dist_entries;
 DistEntry *erts_not_connected_dist_entries; /* including erts_this_dist_entry */
 Sint erts_no_of_hidden_dist_entries;
 Sint erts_no_of_visible_dist_entries;
+Sint erts_no_of_pending_dist_entries;
 Sint erts_no_of_not_connected_dist_entries; /* including erts_this_dist_entry */
 
 DistEntry *erts_this_dist_entry;
@@ -57,6 +61,60 @@ static ErtsMonotonicTime node_tab_delete_delay;
 
 /* -- The distribution table ---------------------------------------------- */
 
+#define ErtsBin2DistEntry(B) \
+    ((DistEntry *) ERTS_MAGIC_BIN_DATA((B)))
+#define ErtsDistEntry2Bin(DEP) \
+    ((Binary *) ERTS_MAGIC_BIN_FROM_DATA((DEP)))
+
+static ERTS_INLINE erts_aint_t
+de_refc_read(DistEntry *dep, erts_aint_t min)
+{
+    return erts_refc_read(&ErtsDistEntry2Bin(dep)->intern.refc, min);
+}
+
+static ERTS_INLINE erts_aint_t
+de_refc_inc_read(DistEntry *dep, erts_aint_t min)
+{
+    return erts_refc_inctest(&ErtsDistEntry2Bin(dep)->intern.refc, min);
+}
+
+static ERTS_INLINE void
+de_refc_inc(DistEntry *dep, erts_aint_t min)
+{
+    erts_refc_inc(&ErtsDistEntry2Bin(dep)->intern.refc, min);
+}
+
+static ERTS_INLINE void
+de_refc_dec(DistEntry *dep, erts_aint_t min)
+{
+#ifdef DEBUG
+    (void) erts_refc_read(&ErtsDistEntry2Bin(dep)->intern.refc, min+1);
+#endif
+    erts_bin_release(ErtsDistEntry2Bin(dep));
+}
+
+static ERTS_INLINE erts_aint_t
+de_refc_dec_read(DistEntry *dep, erts_aint_t min)
+{
+    return erts_refc_dectest(&ErtsDistEntry2Bin(dep)->intern.refc, min);
+}
+
+void
+erts_ref_dist_entry(DistEntry *dep)
+{
+    ASSERT(dep);
+    if (de_refc_inc_read(dep, 1) == 1) {
+        de_refc_inc(dep, 2);  /* Pending delete */
+    }
+}
+
+void
+erts_deref_dist_entry(DistEntry *dep)
+{
+    ASSERT(dep);
+    de_refc_dec(dep, 0);
+}
+
 #ifdef DEBUG
 static int
 is_in_de_list(DistEntry *dep, DistEntry *dep_list)
@@ -85,48 +143,63 @@ dist_table_cmp(void *dep1, void *dep2)
 static void*
 dist_table_alloc(void *dep_tmpl)
 {
+    erts_aint_t refc;
     Eterm sysname;
+    Binary *bin;
     DistEntry *dep;
-    erts_smp_rwmtx_opt_t rwmtx_opt = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
-    rwmtx_opt.type = ERTS_SMP_RWMTX_TYPE_FREQUENT_READ;
+    erts_rwmtx_opt_t rwmtx_opt = ERTS_RWMTX_OPT_DEFAULT_INITER;
+    rwmtx_opt.type = ERTS_RWMTX_TYPE_FREQUENT_READ;
 
     sysname = ((DistEntry *) dep_tmpl)->sysname;
-    dep = (DistEntry *) erts_alloc(ERTS_ALC_T_DIST_ENTRY, sizeof(DistEntry));
+
+    bin = erts_create_magic_binary_x(sizeof(DistEntry),
+                                     erts_dist_entry_destructor,
+                                     ERTS_ALC_T_DIST_ENTRY,
+                                     0);
+    dep = ErtsBin2DistEntry(bin);
 
     dist_entries++;
 
+    refc = de_refc_dec_read(dep, -1);
+    ASSERT(refc == -1); (void)refc;
+
     dep->prev				= NULL;
-    erts_smp_refc_init(&dep->refc, -1);
-    erts_smp_rwmtx_init_opt(&dep->rwmtx, &rwmtx_opt, "dist_entry", sysname,
+    erts_rwmtx_init_opt(&dep->rwmtx, &rwmtx_opt, "dist_entry", sysname,
         ERTS_LOCK_FLAGS_CATEGORY_DISTRIBUTION);
     dep->sysname			= sysname;
     dep->cid				= NIL;
+    erts_atomic_init_nob(&dep->input_handler, (erts_aint_t) NIL);
     dep->connection_id			= 0;
     dep->status				= 0;
     dep->flags				= 0;
     dep->version			= 0;
 
-    erts_smp_mtx_init(&dep->lnk_mtx, "dist_entry_links", sysname,
+    erts_mtx_init(&dep->lnk_mtx, "dist_entry_links", sysname,
         ERTS_LOCK_FLAGS_CATEGORY_DISTRIBUTION);
     dep->node_links			= NULL;
     dep->nlinks				= NULL;
     dep->monitors			= NULL;
 
-    erts_smp_mtx_init(&dep->qlock, "dist_entry_out_queue", sysname,
+    erts_mtx_init(&dep->qlock, "dist_entry_out_queue", sysname,
         ERTS_LOCK_FLAGS_CATEGORY_DISTRIBUTION);
-    dep->qflgs				= 0;
-    dep->qsize				= 0;
+    erts_atomic32_init_nob(&dep->qflgs, 0);
+    erts_atomic_init_nob(&dep->qsize, 0);
+    erts_atomic64_init_nob(&dep->in, 0);
+    erts_atomic64_init_nob(&dep->out, 0);
     dep->out_queue.first		= NULL;
     dep->out_queue.last			= NULL;
     dep->suspended			= NULL;
 
+    dep->tmp_out_queue.first    	= NULL;
+    dep->tmp_out_queue.last     	= NULL;
     dep->finalized_out_queue.first	= NULL;
     dep->finalized_out_queue.last	= NULL;
 
-    erts_smp_atomic_init_nob(&dep->dist_cmd_scheduled, 0);
+    erts_atomic_init_nob(&dep->dist_cmd_scheduled, 0);
     erts_port_task_handle_init(&dep->dist_cmd);
     dep->send				= NULL;
     dep->cache				= NULL;
+    dep->transcode_ctx                  = NULL;
 
     /* Link in */
 
@@ -149,6 +222,8 @@ dist_table_free(void *vdep)
 {
     DistEntry *dep = (DistEntry *) vdep;
 
+    ASSERT(de_refc_read(dep, -1) == -1);
+    ASSERT(dep->status == 0);
     ASSERT(is_nil(dep->cid));
     ASSERT(dep->nlinks == NULL);
     ASSERT(dep->node_links == NULL);
@@ -174,14 +249,14 @@ dist_table_free(void *vdep)
     erts_no_of_not_connected_dist_entries--;
 
     ASSERT(!dep->cache);
-    erts_smp_rwmtx_destroy(&dep->rwmtx);
-    erts_smp_mtx_destroy(&dep->lnk_mtx);
-    erts_smp_mtx_destroy(&dep->qlock);
+    erts_rwmtx_destroy(&dep->rwmtx);
+    erts_mtx_destroy(&dep->lnk_mtx);
+    erts_mtx_destroy(&dep->qlock);
 
 #ifdef DEBUG
     sys_memset(vdep, 0x77, sizeof(DistEntry));
 #endif
-    erts_free(ERTS_ALC_T_DIST_ENTRY, (void *) dep);
+    erts_bin_free(ErtsDistEntry2Bin(dep));
 
     ASSERT(dist_entries > 0);
     dist_entries--;
@@ -193,25 +268,58 @@ erts_dist_table_info(fmtfn_t to, void *to_arg)
 {
     int lock = !ERTS_IS_CRASH_DUMPING;
     if (lock)
-	erts_smp_rwmtx_rlock(&erts_dist_table_rwmtx);
+	erts_rwmtx_rlock(&erts_dist_table_rwmtx);
     hash_info(to, to_arg, &erts_dist_table);
     if (lock)
-	erts_smp_rwmtx_runlock(&erts_dist_table_rwmtx);
+	erts_rwmtx_runlock(&erts_dist_table_rwmtx);
+}
+
+static ERTS_INLINE DistEntry *find_dist_entry(Eterm sysname,
+                                              int inc_refc,
+                                              int connected_only)
+{
+    DistEntry *res;
+    DistEntry de;
+    de.sysname = sysname;
+    erts_rwmtx_rlock(&erts_dist_table_rwmtx);
+    res = hash_get(&erts_dist_table, (void *) &de);
+    if (res) {
+        if (connected_only && is_nil(res->cid))
+            res = NULL;
+        else {
+            int pend_delete;
+            erts_aint_t refc;
+            if (inc_refc) {
+                refc = de_refc_inc_read(res, 1);
+                pend_delete = refc < 2;
+            }
+            else {
+                refc = de_refc_read(res, 0);
+                pend_delete = refc < 1;
+            }
+            if (pend_delete) /* Pending delete */
+                de_refc_inc(res, 1);
+        }
+    }
+    erts_rwmtx_runlock(&erts_dist_table_rwmtx);
+    return res;
 }
 
 DistEntry *
 erts_channel_no_to_dist_entry(Uint cno)
 {
+    /*
+     * Does NOT increase reference count!
+     */
+
 /*
  * For this node (and previous incarnations of this node),
  * ERST_INTERNAL_CHANNEL_NO (will always be 0 I guess) is used as
  * channel no. For other nodes, the atom index of the atom corresponding
  * to the node name is used as channel no.
  */
-    if(cno == ERST_INTERNAL_CHANNEL_NO) {
-	erts_smp_refc_inc(&erts_this_dist_entry->refc, 2);
+    if (cno == ERST_INTERNAL_CHANNEL_NO)
 	return erts_this_dist_entry;
-    }
 
     if((cno > MAX_ATOM_INDEX)
        || (cno >= atom_table_size())
@@ -220,118 +328,174 @@ erts_channel_no_to_dist_entry(Uint cno)
         
     /* cno is a valid atom index; find corresponding dist entry (if there
        is one) */
-    return erts_find_dist_entry(make_atom(cno));
+    return find_dist_entry(make_atom(cno), 0, 0);
 }
 
-
 DistEntry *
 erts_sysname_to_connected_dist_entry(Eterm sysname)
 {
-    DistEntry de;
-    DistEntry *res_dep;
-    de.sysname = sysname;
-  
-    if(erts_this_dist_entry->sysname == sysname) {
-	erts_smp_refc_inc(&erts_this_dist_entry->refc, 2);
+    /*
+     * Does NOT increase reference count!
+     */
+    if(erts_this_dist_entry->sysname == sysname)
 	return erts_this_dist_entry;
-    }
-
-    erts_smp_rwmtx_rlock(&erts_dist_table_rwmtx);
-    res_dep = (DistEntry *) hash_get(&erts_dist_table, (void *) &de);
-    if (res_dep) {
-	erts_aint_t refc = erts_smp_refc_inctest(&res_dep->refc, 1);
-	if (refc < 2) /* Pending delete */
-	    erts_smp_refc_inc(&res_dep->refc, 1);
-    }
-    erts_smp_rwmtx_runlock(&erts_dist_table_rwmtx);
-    if (res_dep) {
-	int deref;
-	erts_smp_rwmtx_rlock(&res_dep->rwmtx);
-	deref = is_nil(res_dep->cid);
-	erts_smp_rwmtx_runlock(&res_dep->rwmtx);
-	if (deref) {
-	    erts_deref_dist_entry(res_dep);
-	    res_dep = NULL;
-	}
-    }
-    return res_dep;
+    return find_dist_entry(sysname, 0, 1);
 }
 
 DistEntry *erts_find_or_insert_dist_entry(Eterm sysname)
 {
+    /*
+     * This function DOES increase reference count!
+     */
     DistEntry *res;
     DistEntry de;
     erts_aint_t refc;
-    res = erts_find_dist_entry(sysname);
+    res = find_dist_entry(sysname, 1, 0);
     if (res)
 	return res;
     de.sysname = sysname;
-    erts_smp_rwmtx_rwlock(&erts_dist_table_rwmtx);
+    erts_rwmtx_rwlock(&erts_dist_table_rwmtx);
     res = hash_put(&erts_dist_table, (void *) &de);
-    refc = erts_smp_refc_inctest(&res->refc, 0);
+    refc = de_refc_inc_read(res, 0);
     if (refc < 2) /* New or pending delete */
-	erts_smp_refc_inc(&res->refc, 1);
-    erts_smp_rwmtx_rwunlock(&erts_dist_table_rwmtx);
+        de_refc_inc(res, 1);
+    erts_rwmtx_rwunlock(&erts_dist_table_rwmtx);
     return res;
 }
 
 DistEntry *erts_find_dist_entry(Eterm sysname)
 {
-    DistEntry *res;
-    DistEntry de;
-    de.sysname = sysname;
-    erts_smp_rwmtx_rlock(&erts_dist_table_rwmtx);
-    res = hash_get(&erts_dist_table, (void *) &de);
-    if (res) {
-	erts_aint_t refc = erts_smp_refc_inctest(&res->refc, 1);
-	if (refc < 2) /* Pending delete */
-	    erts_smp_refc_inc(&res->refc, 1);
+    /*
+     * Does NOT increase reference count!
+     */
+    return find_dist_entry(sysname, 0, 0);
+}
+
+DistEntry *
+erts_dhandle_to_dist_entry(Eterm dhandle)
+{
+    Binary *bin;
+    if (!is_internal_magic_ref(dhandle))
+        return NULL;
+    bin = erts_magic_ref2bin(dhandle);
+    if (ERTS_MAGIC_BIN_DESTRUCTOR(bin) != erts_dist_entry_destructor)
+        return NULL;
+    return ErtsBin2DistEntry(bin);
+}
+
+Eterm
+erts_build_dhandle(Eterm **hpp, ErlOffHeap* ohp, DistEntry *dep)
+{
+    Binary *bin = ErtsDistEntry2Bin(dep);
+    ASSERT(bin);
+    ASSERT(ERTS_MAGIC_BIN_DESTRUCTOR(bin) == erts_dist_entry_destructor);
+    return erts_mk_magic_ref(hpp, ohp, bin);
+}
+
+Eterm
+erts_make_dhandle(Process *c_p, DistEntry *dep)
+{
+    Eterm *hp = HAlloc(c_p, ERTS_MAGIC_REF_THING_SIZE);
+    return erts_build_dhandle(&hp, &c_p->off_heap, dep);
+}
+
+static void start_timer_delete_dist_entry(void *vdep);
+static void prepare_try_delete_dist_entry(void *vdep);
+static void try_delete_dist_entry(DistEntry*);
+
+static void schedule_delete_dist_entry(DistEntry* dep)
+{
+    /*
+     * Here we need thread progress to wait for other threads, that may have
+     * done lookup without refc++, to do either refc++ or drop their refs.
+     *
+     * Note that timeouts do not guarantee thread progress.
+     */
+    erts_schedule_thr_prgr_later_op(start_timer_delete_dist_entry,
+                                    dep, &dep->later_op);
+}
+
+static void
+start_timer_delete_dist_entry(void *vdep)
+{
+    if (node_tab_delete_delay == 0) {
+        prepare_try_delete_dist_entry(vdep);
+    }
+    else {
+        ASSERT(node_tab_delete_delay > 0);
+        erts_start_timer_callback(node_tab_delete_delay,
+                                  prepare_try_delete_dist_entry,
+                                  vdep);
     }
-    erts_smp_rwmtx_runlock(&erts_dist_table_rwmtx);
-    return res;
 }
 
-static void try_delete_dist_entry(void *vdep)
+static void
+prepare_try_delete_dist_entry(void *vdep)
+{
+    DistEntry *dep = vdep;
+    erts_aint_t refc;
+
+    /*
+     * Time has passed since we decremented refc to zero and DistEntry may
+     * have been revived. Do a fast check without table lock first.
+     */
+    refc = de_refc_read(dep, 0);
+    if (refc == 0) {
+        try_delete_dist_entry(dep);
+    }
+    else {
+        /*
+         * Someone has done lookup and done refc++ for us.
+         */
+        refc = de_refc_dec_read(dep, 0);
+        if (refc == 0)
+            schedule_delete_dist_entry(dep);
+    }
+}
+
+static void try_delete_dist_entry(DistEntry* dep)
 {
-    DistEntry *dep = (DistEntry *) vdep;
     erts_aint_t refc;
 
-    erts_smp_rwmtx_rwlock(&erts_dist_table_rwmtx);
+    erts_rwmtx_rwlock(&erts_dist_table_rwmtx);
     /*
      * Another thread might have looked up this dist entry after
      * we decided to delete it (refc became zero). If so, the other
-     * thread incremented refc twice. Once for the new reference
-     * and once for this thread.
+     * thread incremented refc one extra step for this thread.
      *
-     * If refc reach -1, no one has used the entry since we
-     * set up the timer. Delete the entry.
+     * If refc reach -1, no one has done lookup and no one can do lookup
+     * as we have table lock. Delete the entry.
      *
-     * If refc reach 0, the entry is currently not in use
-     * but has been used since we set up the timer. Set up a
-     * new timer.
+     * If refc reach 0, someone raced us and either
+     *  (1) did lookup with own refc++ and already released it again
+     *  (2) did lookup without own refc++
+     * Schedule new delete operation.
      *
      * If refc > 0, the entry is in use. Keep the entry.
      */
-    refc = erts_smp_refc_dectest(&dep->refc, -1);
+    refc = de_refc_dec_read(dep, -1);
     if (refc == -1)
 	(void) hash_erase(&erts_dist_table, (void *) dep);
-    erts_smp_rwmtx_rwunlock(&erts_dist_table_rwmtx);
+    erts_rwmtx_rwunlock(&erts_dist_table_rwmtx);
 
-    if (refc == 0)
-	erts_schedule_delete_dist_entry(dep);
+    if (refc == 0) {
+        schedule_delete_dist_entry(dep);
+    }
 }
 
-void erts_schedule_delete_dist_entry(DistEntry *dep)
+int erts_dist_entry_destructor(Binary *bin)
 {
-    ASSERT(dep != erts_this_dist_entry);
-    if (dep != erts_this_dist_entry) {
-	if (node_tab_delete_delay == 0)
-	    try_delete_dist_entry((void *) dep);
-	else if (node_tab_delete_delay > 0)
-	    erts_start_timer_callback(node_tab_delete_delay,
-				      try_delete_dist_entry,
-				      (void *) dep);
-    }
+    DistEntry *dep = ErtsBin2DistEntry(bin);
+    erts_aint_t refc;
+
+    refc = de_refc_read(dep, -1);
+
+    if (refc == -1)
+        return 1; /* Allow deallocation of structure... */
+
+    schedule_delete_dist_entry(dep);
+
+    return 0;
 }
 
 Uint
@@ -346,7 +510,7 @@ erts_dist_table_size(void)
     int lock = !ERTS_IS_CRASH_DUMPING;
 
     if (lock)
-	erts_smp_rwmtx_rlock(&erts_dist_table_rwmtx);
+	erts_rwmtx_rlock(&erts_dist_table_rwmtx);
 #ifdef DEBUG
     hash_get_info(&hi, &erts_dist_table);
     ASSERT(dist_entries == hi.objs);
@@ -360,12 +524,17 @@ erts_dist_table_size(void)
 	i++;
     ASSERT(i == erts_no_of_hidden_dist_entries);
     i = 0;
+    for(dep = erts_pending_dist_entries; dep; dep = dep->next)
+        i++;
+    ASSERT(i == erts_no_of_pending_dist_entries);
+    i = 0;
     for(dep = erts_not_connected_dist_entries; dep; dep = dep->next)
 	i++;
     ASSERT(i == erts_no_of_not_connected_dist_entries);
 
     ASSERT(dist_entries == (erts_no_of_visible_dist_entries
 			    + erts_no_of_hidden_dist_entries
+                            + erts_no_of_pending_dist_entries
 			    + erts_no_of_not_connected_dist_entries));
 #endif
 
@@ -373,50 +542,53 @@ erts_dist_table_size(void)
 	   + dist_entries*sizeof(DistEntry)
 	   + erts_dist_cache_size());
     if (lock)
-	erts_smp_rwmtx_runlock(&erts_dist_table_rwmtx);
+	erts_rwmtx_runlock(&erts_dist_table_rwmtx);
     return res;
 }
 
 void
 erts_set_dist_entry_not_connected(DistEntry *dep)
 {
-    ERTS_SMP_LC_ASSERT(erts_lc_is_de_rwlocked(dep));
-    erts_smp_rwmtx_rwlock(&erts_dist_table_rwmtx);
+    DistEntry** head;
 
-    ASSERT(dep != erts_this_dist_entry);
-    ASSERT(is_internal_port(dep->cid));
+    ERTS_LC_ASSERT(erts_lc_is_de_rwlocked(dep));
+    erts_rwmtx_rwlock(&erts_dist_table_rwmtx);
 
-    if(dep->flags & DFLAG_PUBLISHED) {
-	if(dep->prev) {
-	    ASSERT(is_in_de_list(dep, erts_visible_dist_entries));
-	    dep->prev->next = dep->next;
-	}
-	else {
-	    ASSERT(erts_visible_dist_entries == dep);
-	    erts_visible_dist_entries = dep->next;
-	}
+    ASSERT(dep != erts_this_dist_entry);
 
-	ASSERT(erts_no_of_visible_dist_entries > 0);
-	erts_no_of_visible_dist_entries--;
+    if (dep->status & ERTS_DE_SFLG_PENDING) {
+        ASSERT(is_nil(dep->cid));
+        ASSERT(erts_no_of_pending_dist_entries > 0);
+        erts_no_of_pending_dist_entries--;
+        head = &erts_pending_dist_entries;
     }
     else {
-	if(dep->prev) {
-	    ASSERT(is_in_de_list(dep, erts_hidden_dist_entries));
-	    dep->prev->next = dep->next;
-	}
-	else {
-	    ASSERT(erts_hidden_dist_entries == dep);
-	    erts_hidden_dist_entries = dep->next;
-	}
-
-	ASSERT(erts_no_of_hidden_dist_entries > 0);
-	erts_no_of_hidden_dist_entries--;
+        ASSERT(dep->status != 0);
+        ASSERT(is_internal_port(dep->cid) || is_internal_pid(dep->cid));
+        if (dep->flags & DFLAG_PUBLISHED) {
+            ASSERT(erts_no_of_visible_dist_entries > 0);
+            erts_no_of_visible_dist_entries--;
+            head = &erts_visible_dist_entries;
+        }
+        else {
+            ASSERT(erts_no_of_hidden_dist_entries > 0);
+            erts_no_of_hidden_dist_entries--;
+            head = &erts_hidden_dist_entries;
+        }
     }
 
+    if(dep->prev) {
+        ASSERT(is_in_de_list(dep, *head));
+        dep->prev->next = dep->next;
+    }
+    else {
+        ASSERT(*head == dep);
+        *head = dep->next;
+    }
     if(dep->next)
 	dep->next->prev = dep->prev;
 
-    dep->status &= ~ERTS_DE_SFLG_CONNECTED;
+    dep->status &= ~(ERTS_DE_SFLG_PENDING | ERTS_DE_SFLG_CONNECTED);
     dep->flags = 0;
     dep->prev = NULL;
     dep->cid = NIL;
@@ -428,41 +600,91 @@ erts_set_dist_entry_not_connected(DistEntry *dep)
     }
     erts_not_connected_dist_entries = dep;
     erts_no_of_not_connected_dist_entries++;
-    erts_smp_rwmtx_rwunlock(&erts_dist_table_rwmtx);
+    erts_rwmtx_rwunlock(&erts_dist_table_rwmtx);
+}
+
+void
+erts_set_dist_entry_pending(DistEntry *dep)
+{
+    ERTS_LC_ASSERT(erts_lc_is_de_rwlocked(dep));
+    erts_rwmtx_rwlock(&erts_dist_table_rwmtx);
+
+    ASSERT(dep != erts_this_dist_entry);
+    ASSERT(dep->status == 0);
+    ASSERT(is_nil(dep->cid));
+
+    if(dep->prev) {
+        ASSERT(is_in_de_list(dep, erts_not_connected_dist_entries));
+        dep->prev->next = dep->next;
+    }
+    else {
+        ASSERT(dep == erts_not_connected_dist_entries);
+        erts_not_connected_dist_entries = dep->next;
+    }
+
+    if(dep->next)
+	dep->next->prev = dep->prev;
+
+    erts_no_of_not_connected_dist_entries--;
+
+    dep->status = ERTS_DE_SFLG_PENDING;
+    dep->flags = (DFLAG_DIST_MANDATORY | DFLAG_DIST_HOPEFULLY);
+    dep->connection_id = (dep->connection_id + 1) & ERTS_DIST_CON_ID_MASK;
+
+    dep->prev = NULL;
+    dep->next = erts_pending_dist_entries;
+    if(erts_pending_dist_entries) {
+	ASSERT(erts_pending_dist_entries->prev == NULL);
+	erts_pending_dist_entries->prev = dep;
+    }
+    erts_pending_dist_entries = dep;
+    erts_no_of_pending_dist_entries++;
+    erts_rwmtx_rwunlock(&erts_dist_table_rwmtx);
 }
 
 void
 erts_set_dist_entry_connected(DistEntry *dep, Eterm cid, Uint flags)
 {
-    ERTS_SMP_LC_ASSERT(erts_lc_is_de_rwlocked(dep));
-    erts_smp_rwmtx_rwlock(&erts_dist_table_rwmtx);
+    erts_aint32_t set_qflgs;
+
+    ERTS_LC_ASSERT(erts_lc_is_de_rwlocked(dep));
+    erts_rwmtx_rwlock(&erts_dist_table_rwmtx);
 
     ASSERT(dep != erts_this_dist_entry);
     ASSERT(is_nil(dep->cid));
-    ASSERT(is_internal_port(cid));
+    ASSERT(dep->status & ERTS_DE_SFLG_PENDING);
+    ASSERT(is_internal_port(cid) || is_internal_pid(cid));
 
     if(dep->prev) {
-	ASSERT(is_in_de_list(dep, erts_not_connected_dist_entries));
+	ASSERT(is_in_de_list(dep, erts_pending_dist_entries));
 	dep->prev->next = dep->next;
     }
     else {
-	ASSERT(erts_not_connected_dist_entries == dep);
-	erts_not_connected_dist_entries = dep->next;
+	ASSERT(erts_pending_dist_entries == dep);
+	erts_pending_dist_entries = dep->next;
     }
 
     if(dep->next)
 	dep->next->prev = dep->prev;
 
-    ASSERT(erts_no_of_not_connected_dist_entries > 0);
-    erts_no_of_not_connected_dist_entries--;
+    ASSERT(erts_no_of_pending_dist_entries > 0);
+    erts_no_of_pending_dist_entries--;
 
+    dep->status &= ~ERTS_DE_SFLG_PENDING;
     dep->status |= ERTS_DE_SFLG_CONNECTED;
-    dep->flags = flags;
+    dep->flags = flags & ~DFLAG_NO_MAGIC;
     dep->cid = cid;
-    dep->connection_id++;
-    dep->connection_id &= ERTS_DIST_EXT_CON_ID_MASK;
+    erts_atomic_set_nob(&dep->input_handler,
+                            (erts_aint_t) cid);
+
     dep->prev = NULL;
 
+    erts_atomic64_set_nob(&dep->in, 0);
+    erts_atomic64_set_nob(&dep->out, 0);
+    set_qflgs = (is_internal_port(cid) ?
+                 ERTS_DE_QFLG_PORT_CTRL : ERTS_DE_QFLG_PROC_CTRL);
+    erts_atomic32_read_bor_nob(&dep->qflgs, set_qflgs);
+
     if(flags & DFLAG_PUBLISHED) {
 	dep->next = erts_visible_dist_entries;
 	if(erts_visible_dist_entries) {
@@ -481,7 +703,7 @@ erts_set_dist_entry_connected(DistEntry *dep, Eterm cid, Uint flags)
 	erts_hidden_dist_entries = dep;
 	erts_no_of_hidden_dist_entries++;
     }
-    erts_smp_rwmtx_rwunlock(&erts_dist_table_rwmtx);
+    erts_rwmtx_rwunlock(&erts_dist_table_rwmtx);
 }
 
 /* -- Node table --------------------------------------------------------- */
@@ -519,7 +741,7 @@ node_table_alloc(void *venp_tmpl)
 
     node_entries++;
 
-    erts_smp_refc_init(&enp->refc, -1);
+    erts_refc_init(&enp->refc, -1);
     enp->creation = ((ErlNode *) venp_tmpl)->creation;
     enp->sysname = ((ErlNode *) venp_tmpl)->sysname;
     enp->dist_entry = erts_find_or_insert_dist_entry(((ErlNode *) venp_tmpl)->sysname);
@@ -532,7 +754,7 @@ node_table_free(void *venp)
 {
     ErlNode *enp = (ErlNode *) venp;
 
-    ERTS_SMP_LC_ASSERT(enp != erts_this_node || erts_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(enp != erts_this_node || erts_thr_progress_is_blocking());
 
     erts_deref_dist_entry(enp->dist_entry);
 #ifdef DEBUG
@@ -553,14 +775,14 @@ erts_node_table_size(void)
 #endif
     int lock = !ERTS_IS_CRASH_DUMPING;
     if (lock)
-	erts_smp_rwmtx_rlock(&erts_node_table_rwmtx);
+	erts_rwmtx_rlock(&erts_node_table_rwmtx);
 #ifdef DEBUG
     hash_get_info(&hi, &erts_node_table);
     ASSERT(node_entries == hi.objs);
 #endif
     res = hash_table_sz(&erts_node_table) + node_entries*sizeof(ErlNode);
     if (lock)
-	erts_smp_rwmtx_runlock(&erts_node_table_rwmtx);
+	erts_rwmtx_runlock(&erts_node_table_rwmtx);
     return res;
 }
 
@@ -569,10 +791,10 @@ erts_node_table_info(fmtfn_t to, void *to_arg)
 {
     int lock = !ERTS_IS_CRASH_DUMPING;
     if (lock)
-	erts_smp_rwmtx_rlock(&erts_node_table_rwmtx);
+	erts_rwmtx_rlock(&erts_node_table_rwmtx);
     hash_info(to, to_arg, &erts_node_table);
     if (lock)
-	erts_smp_rwmtx_runlock(&erts_node_table_rwmtx);
+	erts_rwmtx_runlock(&erts_node_table_rwmtx);
 }
 
 
@@ -583,26 +805,26 @@ ErlNode *erts_find_or_insert_node(Eterm sysname, Uint32 creation)
     ne.sysname = sysname;
     ne.creation = creation;
 
-    erts_smp_rwmtx_rlock(&erts_node_table_rwmtx);
+    erts_rwmtx_rlock(&erts_node_table_rwmtx);
     res = hash_get(&erts_node_table, (void *) &ne);
     if (res && res != erts_this_node) {
-	erts_aint_t refc = erts_smp_refc_inctest(&res->refc, 0);
+	erts_aint_t refc = erts_refc_inctest(&res->refc, 0);
 	if (refc < 2) /* New or pending delete */
-	    erts_smp_refc_inc(&res->refc, 1);
+	    erts_refc_inc(&res->refc, 1);
     }
-    erts_smp_rwmtx_runlock(&erts_node_table_rwmtx);
+    erts_rwmtx_runlock(&erts_node_table_rwmtx);
     if (res)
 	return res;
 
-    erts_smp_rwmtx_rwlock(&erts_node_table_rwmtx);
+    erts_rwmtx_rwlock(&erts_node_table_rwmtx);
     res = hash_put(&erts_node_table, (void *) &ne);
     ASSERT(res);
     if (res != erts_this_node) {
-	erts_aint_t refc = erts_smp_refc_inctest(&res->refc, 0);
+	erts_aint_t refc = erts_refc_inctest(&res->refc, 0);
 	if (refc < 2) /* New or pending delete */
-	    erts_smp_refc_inc(&res->refc, 1);
+	    erts_refc_inc(&res->refc, 1);
     }
-    erts_smp_rwmtx_rwunlock(&erts_node_table_rwmtx);
+    erts_rwmtx_rwunlock(&erts_node_table_rwmtx);
     return res;
 }
 
@@ -611,7 +833,7 @@ static void try_delete_node(void *venp)
     ErlNode *enp = (ErlNode *) venp;
     erts_aint_t refc;
 
-    erts_smp_rwmtx_rwlock(&erts_node_table_rwmtx);
+    erts_rwmtx_rwlock(&erts_node_table_rwmtx);
     /*
      * Another thread might have looked up this node after we
      * decided to delete it (refc became zero). If so, the other
@@ -627,10 +849,10 @@ static void try_delete_node(void *venp)
      *
      * If refc > 0, the entry is in use. Keep the entry.
      */
-    refc = erts_smp_refc_dectest(&enp->refc, -1);
+    refc = erts_refc_dectest(&enp->refc, -1);
     if (refc == -1)
 	(void) hash_erase(&erts_node_table, (void *) enp);
-    erts_smp_rwmtx_rwunlock(&erts_node_table_rwmtx);
+    erts_rwmtx_rwunlock(&erts_node_table_rwmtx);
 
     if (refc == 0)
 	erts_schedule_delete_node(enp);
@@ -673,7 +895,7 @@ static void print_node(void *venp, void *vpndp)
 	erts_print(pndp->to, pndp->to_arg, " %d", enp->creation);
 #ifdef DEBUG
 	erts_print(pndp->to, pndp->to_arg, " (refc=%ld)",
-		   erts_smp_refc_read(&enp->refc, 0));
+		   erts_refc_read(&enp->refc, 0));
 #endif
 	pndp->no_sysname++;
     }
@@ -696,13 +918,13 @@ void erts_print_node_info(fmtfn_t to,
     pnd.no_total = 0;
 
     if (lock)
-	erts_smp_rwmtx_rlock(&erts_node_table_rwmtx);
+	erts_rwmtx_rlock(&erts_node_table_rwmtx);
     hash_foreach(&erts_node_table, print_node, (void *) &pnd);
     if (pnd.no_sysname != 0) {
 	erts_print(to, to_arg, "\n");
     }
     if (lock)
-	erts_smp_rwmtx_runlock(&erts_node_table_rwmtx);
+	erts_rwmtx_runlock(&erts_node_table_rwmtx);
 
     if(no_sysname)
 	*no_sysname = pnd.no_sysname;
@@ -715,20 +937,19 @@ void erts_print_node_info(fmtfn_t to,
 void
 erts_set_this_node(Eterm sysname, Uint creation)
 {
-    ERTS_SMP_LC_ASSERT(erts_thr_progress_is_blocking());
-    ASSERT(erts_smp_refc_read(&erts_this_dist_entry->refc, 2));
+    ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
+    ASSERT(2 <= de_refc_read(erts_this_dist_entry, 2));
 
-    if (erts_smp_refc_dectest(&erts_this_node->refc, 0) == 0)
+    if (erts_refc_dectest(&erts_this_node->refc, 0) == 0)
         try_delete_node(erts_this_node);
 
-    if (erts_smp_refc_dectest(&erts_this_dist_entry->refc, 0) == 0)
-        try_delete_dist_entry(erts_this_dist_entry);
+    erts_deref_dist_entry(erts_this_dist_entry);
 
     erts_this_node = NULL; /* to make sure refc is bumped for this node */
     erts_this_node = erts_find_or_insert_node(sysname, creation);
     erts_this_dist_entry = erts_this_node->dist_entry;
 
-    erts_smp_refc_inc(&erts_this_dist_entry->refc, 2);
+    erts_ref_dist_entry(erts_this_dist_entry);
 
     erts_this_node_sysname = erts_this_node_sysname_BUFFER;
     erts_snprintf(erts_this_node_sysname, sizeof(erts_this_node_sysname_BUFFER),
@@ -747,7 +968,7 @@ erts_delayed_node_table_gc(void)
 
 void erts_init_node_tables(int dd_sec)
 {
-    erts_smp_rwmtx_opt_t rwmtx_opt = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
+    erts_rwmtx_opt_t rwmtx_opt = ERTS_RWMTX_OPT_DEFAULT_INITER;
     HashFunctions f;
     ErlNode node_tmpl;
 
@@ -758,12 +979,12 @@ void erts_init_node_tables(int dd_sec)
 
     orig_node_tab_delete_delay = node_tab_delete_delay;
 
-    rwmtx_opt.type = ERTS_SMP_RWMTX_TYPE_FREQUENT_READ;
-    rwmtx_opt.lived = ERTS_SMP_RWMTX_LONG_LIVED;
+    rwmtx_opt.type = ERTS_RWMTX_TYPE_FREQUENT_READ;
+    rwmtx_opt.lived = ERTS_RWMTX_LONG_LIVED;
 
-    erts_smp_rwmtx_init_opt(&erts_node_table_rwmtx, &rwmtx_opt, "node_table", NIL,
+    erts_rwmtx_init_opt(&erts_node_table_rwmtx, &rwmtx_opt, "node_table", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_DISTRIBUTION);
-    erts_smp_rwmtx_init_opt(&erts_dist_table_rwmtx, &rwmtx_opt, "dist_table", NIL,
+    erts_rwmtx_init_opt(&erts_dist_table_rwmtx, &rwmtx_opt, "dist_table", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_DISTRIBUTION);
 
     f.hash       = (H_FUN)		dist_table_hash;
@@ -783,23 +1004,25 @@ void erts_init_node_tables(int dd_sec)
 
     erts_hidden_dist_entries				= NULL;
     erts_visible_dist_entries				= NULL;
+    erts_pending_dist_entries			        = NULL;
     erts_not_connected_dist_entries			= NULL;
     erts_no_of_hidden_dist_entries			= 0;
     erts_no_of_visible_dist_entries			= 0;
+    erts_no_of_pending_dist_entries			= 0;
     erts_no_of_not_connected_dist_entries		= 0;
 
     node_tmpl.sysname = am_Noname;
     node_tmpl.creation = 0;
     erts_this_node = hash_put(&erts_node_table, &node_tmpl);
      /* +1 for erts_this_node */
-    erts_smp_refc_init(&erts_this_node->refc, 1);
+    erts_refc_init(&erts_this_node->refc, 1);
 
     ASSERT(erts_this_node->dist_entry != NULL);
     erts_this_dist_entry = erts_this_node->dist_entry;
     /* +1 for erts_this_dist_entry */
-    /* +1 for erts_this_node->dist_entry */
-    erts_smp_refc_init(&erts_this_dist_entry->refc, 2);
+    erts_ref_dist_entry(erts_this_dist_entry);
 
+    ASSERT(2 == de_refc_read(erts_this_dist_entry, 2));
 
     erts_this_node_sysname = erts_this_node_sysname_BUFFER;
     erts_snprintf(erts_this_node_sysname, sizeof(erts_this_node_sysname_BUFFER),
@@ -808,18 +1031,16 @@ void erts_init_node_tables(int dd_sec)
     references_atoms_need_init = 1;
 }
 
-#ifdef ERTS_SMP
 #ifdef ERTS_ENABLE_LOCK_CHECK
 int erts_lc_is_de_rwlocked(DistEntry *dep)
 {
-    return erts_smp_lc_rwmtx_is_rwlocked(&dep->rwmtx);
+    return erts_lc_rwmtx_is_rwlocked(&dep->rwmtx);
 }
 int erts_lc_is_de_rlocked(DistEntry *dep)
 {
-    return erts_smp_lc_rwmtx_is_rlocked(&dep->rwmtx);
+    return erts_lc_rwmtx_is_rlocked(&dep->rwmtx);
 }
 #endif
-#endif
 
 #ifdef ERTS_ENABLE_LOCK_COUNT
 
@@ -841,10 +1062,10 @@ static void erts_lcnt_enable_dist_lock_count(void *dep_raw, void *enable) {
 }
 
 void erts_lcnt_update_distribution_locks(int enable) {
-    erts_smp_rwmtx_rlock(&erts_dist_table_rwmtx);
+    erts_rwmtx_rlock(&erts_dist_table_rwmtx);
     hash_foreach(&erts_dist_table, erts_lcnt_enable_dist_lock_count,
         (void*)(UWord)enable);
-    erts_smp_rwmtx_runlock(&erts_dist_table_rwmtx);
+    erts_rwmtx_runlock(&erts_dist_table_rwmtx);
 }
 #endif
 
@@ -878,6 +1099,7 @@ static Eterm AM_node_references;
 static Eterm AM_system;
 static Eterm AM_timer;
 static Eterm AM_delayed_delete_timer;
+static Eterm AM_thread_progress_delete_timer;
 
 static void setup_reference_table(void);
 static Eterm reference_table_term(Uint **hpp, ErlOffHeap *ohp, Uint *szp);
@@ -912,6 +1134,7 @@ typedef struct {
 typedef struct dist_referrer_ {
     struct dist_referrer_ *next;
     int heap_ref;
+    int ets_ref;
     int node_ref;
     int ctrl_ref;
     int system_ref;
@@ -946,8 +1169,8 @@ erts_get_node_and_dist_references(struct process *proc)
     Uint *endp;
 #endif
 
-    erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
-    erts_smp_thr_progress_block();
+    erts_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
+    erts_thr_progress_block();
     /* No need to lock any thing since we are alone... */
 
     if (references_atoms_need_init) {
@@ -967,6 +1190,7 @@ erts_get_node_and_dist_references(struct process *proc)
 	INIT_AM(timer);
 	INIT_AM(system);
 	INIT_AM(delayed_delete_timer);
+        INIT_AM(thread_progress_delete_timer);
 	references_atoms_need_init = 0;
     }
 
@@ -989,8 +1213,8 @@ erts_get_node_and_dist_references(struct process *proc)
 
     delete_reference_table();
 
-    erts_smp_thr_progress_unblock();
-    erts_smp_proc_lock(proc, ERTS_PROC_LOCK_MAIN);
+    erts_thr_progress_unblock();
+    erts_proc_lock(proc, ERTS_PROC_LOCK_MAIN);
     return res;
 }
 
@@ -1029,10 +1253,11 @@ insert_dist_referrer(ReferredDist *referred_dist,
 	else {
 	    Uint *hp = &drp->id_heap[0];
 	    ASSERT(is_tuple(id));
-	    drp->id = copy_struct(id, size_object(id), &hp, NULL);
+            drp->id = copy_struct(id, size_object(id), &hp, NULL);
 	}
 	drp->creation = creation;
 	drp->heap_ref = 0;
+        drp->ets_ref = 0;
 	drp->node_ref = 0;
 	drp->ctrl_ref = 0;
 	drp->system_ref = 0;
@@ -1042,6 +1267,7 @@ insert_dist_referrer(ReferredDist *referred_dist,
     case NODE_REF:	drp->node_ref++;	break;
     case CTRL_REF:	drp->ctrl_ref++;	break;
     case HEAP_REF:	drp->heap_ref++;	break;
+    case ETS_REF:	drp->ets_ref++;	        break;
     case SYSTEM_REF:	drp->system_ref++;	break;
     default:		ASSERT(0);
     }
@@ -1150,6 +1376,15 @@ insert_offheap2(ErlOffHeap *oh, void *arg)
     insert_offheap(oh, a->type, a->id);
 }
 
+#define ErtsIsDistEntryBinary(Bin)                                      \
+    (((Bin)->intern.flags & BIN_FLAG_MAGIC)                             \
+     && ERTS_MAGIC_BIN_DESTRUCTOR((Bin)) == erts_dist_entry_destructor)
+
+#define IsSendCtxBinary(Bin)                                            \
+    (((Bin)->intern.flags & BIN_FLAG_MAGIC)                             \
+     && ERTS_MAGIC_BIN_DESTRUCTOR((Bin)) == erts_dsend_context_dtor)
+
+
 static void
 insert_offheap(ErlOffHeap *oh, int type, Eterm id)
 {
@@ -1160,7 +1395,10 @@ insert_offheap(ErlOffHeap *oh, int type, Eterm id)
     for (u.hdr = oh->first; u.hdr; u.hdr = u.hdr->next) {
 	switch (thing_subtag(u.hdr->thing_word)) {
 	case REF_SUBTAG:
-	    if(IsMatchProgBinary(u.mref->mb)) {
+            if (ErtsIsDistEntryBinary(u.mref->mb))
+                insert_dist_entry(ErtsBin2DistEntry(u.mref->mb),
+                                  type, id, 0);
+	    else if(IsMatchProgBinary(u.mref->mb)) {
 		InsertedBin *ib;
 		int insert_bin = 1;
 		for (ib = inserted_bins; ib; ib = ib->next)
@@ -1183,7 +1421,12 @@ insert_offheap(ErlOffHeap *oh, int type, Eterm id)
 		    inserted_bins = nib;
 		    UnUseTmpHeapNoproc(BIG_UINT_HEAP_SIZE);
 		}
-	    }		
+	    }
+            else if (IsSendCtxBinary(u.mref->mb)) {
+                ErtsSendContext* ctx = ERTS_MAGIC_BIN_DATA(u.mref->mb);
+                if (ctx->deref_dep)
+                    insert_dist_entry(ctx->dep, type, id, 0);
+            }
 	    break;
 	case REFC_BINARY_SUBTAG:
 	case FUN_SUBTAG:
@@ -1292,25 +1535,32 @@ init_referred_dist(void *dist, void *unused)
     no_referred_dists++;
 }
 
-#ifdef ERTS_SMP
 static void
 insert_sys_msg(Eterm from, Eterm to, Eterm msg, ErlHeapFragment *bp)
 {
     insert_offheap(&bp->off_heap, HEAP_REF, to);
 }
-#endif
 
 static void
 insert_delayed_delete_node(void *state,
 			   ErtsMonotonicTime timeout_pos,
 			   void *vnp)
 {
-    DeclareTmpHeapNoproc(heap,3);
-    UseTmpHeapNoproc(3);
+    Eterm heap[3];
     insert_node((ErlNode *) vnp,
 		SYSTEM_REF,
 		TUPLE2(&heap[0], AM_system, AM_delayed_delete_timer));
-    UnUseTmpHeapNoproc(3);
+}
+
+static void
+insert_thr_prgr_delete_dist_entry(void *arg, ErtsThrPrgrVal thr_prgr, void *vdep)
+{
+    DistEntry *dep = vdep;
+    Eterm heap[3];
+    insert_dist_entry(dep,
+		      SYSTEM_REF,
+		      TUPLE2(&heap[0], AM_system, AM_thread_progress_delete_timer),
+		      0);
 }
 
 static void
@@ -1318,13 +1568,12 @@ insert_delayed_delete_dist_entry(void *state,
 				 ErtsMonotonicTime timeout_pos,
 				 void *vdep)
 {
-    DeclareTmpHeapNoproc(heap,3);
-    UseTmpHeapNoproc(3);
-    insert_dist_entry((DistEntry *) vdep,
+    DistEntry *dep = vdep;
+    Eterm heap[3];
+    insert_dist_entry(dep,
 		      SYSTEM_REF,
 		      TUPLE2(&heap[0], AM_system, AM_delayed_delete_timer),
 		      0);
-    UnUseTmpHeapNoproc(3);
 }
 
 static void
@@ -1358,9 +1607,12 @@ setup_reference_table(void)
     erts_debug_callback_timer_foreach(try_delete_node,
 				      insert_delayed_delete_node,
 				      NULL);
-    erts_debug_callback_timer_foreach(try_delete_dist_entry,
+    erts_debug_callback_timer_foreach(prepare_try_delete_dist_entry,
 				      insert_delayed_delete_dist_entry,
 				      NULL);
+    erts_debug_later_op_foreach(start_timer_delete_dist_entry,
+                                insert_thr_prgr_delete_dist_entry,
+                                NULL);
 
     UseTmpHeapNoproc(3);
     insert_node(erts_this_node,
@@ -1381,9 +1633,7 @@ setup_reference_table(void)
 	    int mli;
 	    ErtsMessage *msg_list[] = {
 		proc->msg.first,
-#ifdef ERTS_SMP
 		proc->msg_inq.first,
-#endif
 		proc->msg_frag};
 
 	    /* Insert Heap */
@@ -1427,12 +1677,18 @@ setup_reference_table(void)
 		insert_links(ERTS_P_LINKS(proc), proc->common.id);
 	    if (ERTS_P_MONITORS(proc))
 		insert_monitors(ERTS_P_MONITORS(proc), proc->common.id);
+            {
+                DistEntry *dep = ERTS_PROC_GET_DIST_ENTRY(proc);
+                if (dep)
+                    insert_dist_entry(dep,
+                                      CTRL_REF,
+                                      proc->common.id,
+                                      0);
+            }
 	}
     }
     
-#ifdef ERTS_SMP
     erts_foreach_sys_msg_in_q(insert_sys_msg);
-#endif
 
     /* Insert all ports */
     max = erts_ptab_max(&erts_port);
@@ -1520,6 +1776,15 @@ setup_reference_table(void)
 	    insert_monitors(dep->monitors, dep->sysname);
     }
 
+    for(dep = erts_pending_dist_entries; dep; dep = dep->next) {
+        if(dep->nlinks)
+            insert_links2(dep->nlinks, dep->sysname);
+        if(dep->node_links)
+            insert_links(dep->node_links, dep->sysname);
+        if(dep->monitors)
+            insert_monitors(dep->monitors, dep->sysname);
+    }
+
     /* Not connected dist entries should not have any links,
        but inspect them anyway */
     for(dep = erts_not_connected_dist_entries; dep; dep = dep->next) {
@@ -1666,7 +1931,7 @@ reference_table_term(Uint **hpp, ErlOffHeap *ohp, Uint *szp)
 
 	tup = MK_2TUP(referred_nodes[i].node->sysname,
 		      MK_UINT(referred_nodes[i].node->creation));
-	tup = MK_3TUP(tup, MK_UINT(erts_smp_refc_read(&referred_nodes[i].node->refc, 0)), nril);
+	tup = MK_3TUP(tup, MK_UINT(erts_refc_read(&referred_nodes[i].node->refc, 0)), nril);
 	nl = MK_CONS(tup, nl);
     }
 
@@ -1689,6 +1954,10 @@ reference_table_term(Uint **hpp, ErlOffHeap *ohp, Uint *szp)
 		tup = MK_2TUP(AM_heap, MK_UINT(drp->heap_ref));
 		drl = MK_CONS(tup, drl);
 	    }
+            if(drp->ets_ref) {
+                tup = MK_2TUP(AM_ets, MK_UINT(drp->ets_ref));
+                drl = MK_CONS(tup, drl);
+            }
 	    if(drp->system_ref) {
 		tup = MK_2TUP(AM_system, MK_UINT(drp->system_ref));
 		drl = MK_CONS(tup, drl);
@@ -1705,12 +1974,17 @@ reference_table_term(Uint **hpp, ErlOffHeap *ohp, Uint *szp)
 	    else if (is_tuple(drp->id)) {
 		Eterm *t;
 		ASSERT(drp->system_ref && !drp->node_ref
-		       && !drp->ctrl_ref && !drp->heap_ref);
+		       && !drp->ctrl_ref && !drp->heap_ref && !drp->ets_ref);
 		t = tuple_val(drp->id);
 		ASSERT(2 == arityval(t[0]));
 		tup = MK_2TUP(t[1], t[2]);
 	    }
-	    else {
+	    else if (drp->ets_ref) {
+                ASSERT(!drp->heap_ref && !drp->node_ref &&
+                       !drp->ctrl_ref && !drp->system_ref);
+                tup = MK_2TUP(AM_ets, drp->id);
+            }
+            else {
 		ASSERT(!drp->ctrl_ref && drp->node_ref);
 		ASSERT(is_atom(drp->id));
 		tup = MK_2TUP(drp->id, MK_UINT(drp->creation));
@@ -1727,7 +2001,7 @@ reference_table_term(Uint **hpp, ErlOffHeap *ohp, Uint *szp)
 
 	/* DistList = [{Dist, Refc, ReferenceIdList}] */
 	tup = MK_3TUP(referred_dists[i].dist->sysname,
-		      MK_UINT(erts_smp_refc_read(&referred_dists[i].dist->refc, 0)),
+		      MK_UINT(de_refc_read(referred_dists[i].dist, 0)),
 		      dril);
 	dl = MK_CONS(tup, dl);
     }
@@ -1786,12 +2060,12 @@ delete_reference_table(void)
 void
 erts_debug_test_node_tab_delayed_delete(Sint64 millisecs)
 {
-    erts_smp_thr_progress_block();
+    erts_thr_progress_block();
 
     if (millisecs < 0)
 	node_tab_delete_delay = orig_node_tab_delete_delay;
     else
 	node_tab_delete_delay = millisecs;
 
-    erts_smp_thr_progress_unblock();
+    erts_thr_progress_unblock();
 }
diff --git a/erts/emulator/beam/erl_node_tables.h b/erts/emulator/beam/erl_node_tables.h
index 91bcb4fce1..8d29c83e15 100644
--- a/erts/emulator/beam/erl_node_tables.h
+++ b/erts/emulator/beam/erl_node_tables.h
@@ -44,10 +44,12 @@
 #include "erl_alloc.h"
 #include "erl_process.h"
 #include "erl_monitors.h"
-#include "erl_smp.h"
 #define ERTS_PORT_TASK_ONLY_BASIC_TYPES__
 #include "erl_port_task.h"
 #undef ERTS_PORT_TASK_ONLY_BASIC_TYPES__
+#define ERTS_BINARY_TYPES_ONLY__
+#include "erl_binary.h"
+#undef ERTS_BINARY_TYPES_ONLY__
 
 #define ERTS_NODE_TAB_DELAY_GC_DEFAULT (60)
 #define ERTS_NODE_TAB_DELAY_GC_MAX (100*1000*1000)
@@ -55,17 +57,21 @@
  
 #define ERST_INTERNAL_CHANNEL_NO 0
 
-#define ERTS_DE_SFLG_CONNECTED			(((Uint32) 1) <<  0)
-#define ERTS_DE_SFLG_EXITING			(((Uint32) 1) <<  1)
+#define ERTS_DE_SFLG_PENDING			(((Uint32) 1) <<  0)
+#define ERTS_DE_SFLG_CONNECTED			(((Uint32) 1) <<  1)
+#define ERTS_DE_SFLG_EXITING			(((Uint32) 1) <<  2)
 
-#define ERTS_DE_SFLGS_ALL			(ERTS_DE_SFLG_CONNECTED \
-						 | ERTS_DE_SFLG_EXITING)
-
-#define ERTS_DE_QFLG_BUSY			(((Uint32) 1) <<  0)
-#define ERTS_DE_QFLG_EXIT			(((Uint32) 1) <<  1)
+#define ERTS_DE_QFLG_BUSY			(((erts_aint32_t) 1) <<  0)
+#define ERTS_DE_QFLG_EXIT			(((erts_aint32_t) 1) <<  1)
+#define ERTS_DE_QFLG_REQ_INFO			(((erts_aint32_t) 1) <<  2)
+#define ERTS_DE_QFLG_PORT_CTRL                  (((erts_aint32_t) 1) <<  3)
+#define ERTS_DE_QFLG_PROC_CTRL                  (((erts_aint32_t) 1) <<  4)
 
 #define ERTS_DE_QFLGS_ALL			(ERTS_DE_QFLG_BUSY \
-						 | ERTS_DE_QFLG_EXIT)
+						 | ERTS_DE_QFLG_EXIT \
+                                                 | ERTS_DE_QFLG_REQ_INFO \
+                                                 | ERTS_DE_QFLG_PORT_CTRL \
+                                                 | ERTS_DE_QFLG_PROC_CTRL)
 
 #if defined(ARCH_64)
 #define ERTS_DIST_OUTPUT_BUF_DBG_PATTERN ((Uint) 0xf713f713f713f713UL)
@@ -77,10 +83,12 @@ typedef struct ErtsDistOutputBuf_ ErtsDistOutputBuf;
 struct ErtsDistOutputBuf_ {
 #ifdef DEBUG
     Uint dbg_pattern;
+    byte *alloc_endp;
 #endif
     ErtsDistOutputBuf *next;
     byte *extp;
     byte *ext_endp;
+    byte *msg_start;
     byte data[1];
 };
 
@@ -101,18 +109,17 @@ struct ErtsProcList_;
  *   unlock mutexes with higher numbers before mutexes with higher numbers.
  */
 
-struct erl_link;
-
 typedef struct dist_entry_ {
     HashBucket hash_bucket;     /* Hash bucket */
     struct dist_entry_ *next;	/* Next entry in dist_table (not sorted) */
     struct dist_entry_ *prev;	/* Previous entry in dist_table (not sorted) */
-    erts_smp_refc_t refc;		/* Reference count */
 
-    erts_smp_rwmtx_t rwmtx;     /* Protects all fields below until lck_mtx. */
+    erts_rwmtx_t rwmtx;         /* Protects all fields below until lck_mtx. */
     Eterm sysname;		/* name@host atom for efficiency */
     Uint32 creation;		/* creation of connected node */
-    Eterm cid;			/* connection handler (pid or port), NIL == free */
+    erts_atomic_t input_handler; /* Input handler */
+    Eterm cid;			/* connection handler (pid or port),
+                                   NIL == free */
     Uint32 connection_id;	/* Connection id incremented on connect */
     Uint32 status;		/* Slot status, like exiting reserved etc */
     Uint32 flags;		/* Distribution flags, like hidden, 
@@ -120,7 +127,7 @@ typedef struct dist_entry_ {
     unsigned long version;	/* Protocol version */
 
 
-    erts_smp_mtx_t lnk_mtx;     /* Protects node_links, nlinks, and
+    erts_mtx_t lnk_mtx;         /* Protects node_links, nlinks, and
 				   monitors. */
     ErtsLink *node_links;       /* In a dist entry, node links are kept 
 				   in a separate tree, while they are 
@@ -132,24 +139,31 @@ typedef struct dist_entry_ {
     ErtsLink *nlinks;           /* Link tree with subtrees */
     ErtsMonitor *monitors;      /* Monitor tree */
 
-    erts_smp_mtx_t qlock;       /* Protects qflgs and out_queue */
-    Uint32 qflgs;
-    Sint qsize;
+    erts_mtx_t qlock;           /* Protects qflgs and out_queue */
+    erts_atomic32_t qflgs;
+    erts_atomic_t qsize;
+    erts_atomic64_t in;
+    erts_atomic64_t out;
     ErtsDistOutputQueue out_queue;
     struct ErtsProcList_ *suspended;
 
+    ErtsDistOutputQueue tmp_out_queue;
     ErtsDistOutputQueue finalized_out_queue;
-    erts_smp_atomic_t dist_cmd_scheduled;
+    erts_atomic_t dist_cmd_scheduled;
     ErtsPortTaskHandle dist_cmd;
 
     Uint (*send)(Port *prt, ErtsDistOutputBuf *obuf);
 
     struct cache* cache;	/* The atom cache */
+
+    ErtsThrPrgrLaterOp later_op;
+
+    struct transcode_context* transcode_ctx;
 } DistEntry;
 
 typedef struct erl_node_ {
   HashBucket hash_bucket;	/* Hash bucket */
-  erts_smp_refc_t refc;		/* Reference count */
+  erts_refc_t refc;		/* Reference count */
   Eterm	sysname;		/* name@host atom for efficiency */
   Uint32 creation;		/* Creation */
   DistEntry *dist_entry;	/* Corresponding dist entry */
@@ -158,14 +172,16 @@ typedef struct erl_node_ {
 
 extern Hash erts_dist_table;
 extern Hash erts_node_table;
-extern erts_smp_rwmtx_t erts_dist_table_rwmtx;
-extern erts_smp_rwmtx_t erts_node_table_rwmtx;
+extern erts_rwmtx_t erts_dist_table_rwmtx;
+extern erts_rwmtx_t erts_node_table_rwmtx;
 
 extern DistEntry *erts_hidden_dist_entries;
 extern DistEntry *erts_visible_dist_entries;
+extern DistEntry *erts_pending_dist_entries;
 extern DistEntry *erts_not_connected_dist_entries;
 extern Sint erts_no_of_hidden_dist_entries;
 extern Sint erts_no_of_visible_dist_entries;
+extern Sint erts_no_of_pending_dist_entries;
 extern Sint erts_no_of_not_connected_dist_entries;
 
 extern DistEntry *erts_this_dist_entry;
@@ -181,6 +197,7 @@ void erts_schedule_delete_dist_entry(DistEntry *);
 Uint erts_dist_table_size(void);
 void erts_dist_table_info(fmtfn_t, void *);
 void erts_set_dist_entry_not_connected(DistEntry *);
+void erts_set_dist_entry_pending(DistEntry *);
 void erts_set_dist_entry_connected(DistEntry *, Eterm, Uint);
 ErlNode *erts_find_or_insert_node(Eterm, Uint32);
 void erts_schedule_delete_node(ErlNode *);
@@ -190,80 +207,74 @@ void erts_init_node_tables(int);
 void erts_node_table_info(fmtfn_t, void *);
 void erts_print_node_info(fmtfn_t, void *, Eterm, int*, int*);
 Eterm erts_get_node_and_dist_references(struct process *);
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
 int erts_lc_is_de_rwlocked(DistEntry *);
 int erts_lc_is_de_rlocked(DistEntry *);
 #endif
+int erts_dist_entry_destructor(Binary *bin);
+DistEntry *erts_dhandle_to_dist_entry(Eterm dhandle);
+Eterm erts_build_dhandle(Eterm **hpp, ErlOffHeap*, DistEntry*);
+Eterm erts_make_dhandle(Process *c_p, DistEntry *dep);
+void erts_ref_dist_entry(DistEntry *dep);
+void erts_deref_dist_entry(DistEntry *dep);
 
-#ifdef ERTS_ENABLE_LOCK_COUNT
-void erts_lcnt_update_distribution_locks(int enable);
-#endif
-
-ERTS_GLB_INLINE void erts_deref_dist_entry(DistEntry *dep);
 ERTS_GLB_INLINE void erts_deref_node_entry(ErlNode *np);
-ERTS_GLB_INLINE void erts_smp_de_rlock(DistEntry *dep);
-ERTS_GLB_INLINE void erts_smp_de_runlock(DistEntry *dep);
-ERTS_GLB_INLINE void erts_smp_de_rwlock(DistEntry *dep);
-ERTS_GLB_INLINE void erts_smp_de_rwunlock(DistEntry *dep);
-ERTS_GLB_INLINE void erts_smp_de_links_lock(DistEntry *dep);
-ERTS_GLB_INLINE void erts_smp_de_links_unlock(DistEntry *dep);
+ERTS_GLB_INLINE void erts_de_rlock(DistEntry *dep);
+ERTS_GLB_INLINE void erts_de_runlock(DistEntry *dep);
+ERTS_GLB_INLINE void erts_de_rwlock(DistEntry *dep);
+ERTS_GLB_INLINE void erts_de_rwunlock(DistEntry *dep);
+ERTS_GLB_INLINE void erts_de_links_lock(DistEntry *dep);
+ERTS_GLB_INLINE void erts_de_links_unlock(DistEntry *dep);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
 ERTS_GLB_INLINE void
-erts_deref_dist_entry(DistEntry *dep)
-{
-    ASSERT(dep);
-    if (erts_smp_refc_dectest(&dep->refc, 0) == 0)
-	erts_schedule_delete_dist_entry(dep);
-}
-
-ERTS_GLB_INLINE void
 erts_deref_node_entry(ErlNode *np)
 {
     ASSERT(np);
-    if (erts_smp_refc_dectest(&np->refc, 0) == 0)
+    if (erts_refc_dectest(&np->refc, 0) == 0)
 	erts_schedule_delete_node(np);
 }
 
 ERTS_GLB_INLINE void
-erts_smp_de_rlock(DistEntry *dep)
+erts_de_rlock(DistEntry *dep)
 {
-    erts_smp_rwmtx_rlock(&dep->rwmtx);
+    erts_rwmtx_rlock(&dep->rwmtx);
 }
 
 ERTS_GLB_INLINE void
-erts_smp_de_runlock(DistEntry *dep)
+erts_de_runlock(DistEntry *dep)
 {
-    erts_smp_rwmtx_runlock(&dep->rwmtx);
+    erts_rwmtx_runlock(&dep->rwmtx);
 }
 
 ERTS_GLB_INLINE void
-erts_smp_de_rwlock(DistEntry *dep)
+erts_de_rwlock(DistEntry *dep)
 {
-    erts_smp_rwmtx_rwlock(&dep->rwmtx);
+    erts_rwmtx_rwlock(&dep->rwmtx);
 }
 
 ERTS_GLB_INLINE void
-erts_smp_de_rwunlock(DistEntry *dep)
+erts_de_rwunlock(DistEntry *dep)
 {
-    erts_smp_rwmtx_rwunlock(&dep->rwmtx);
+    erts_rwmtx_rwunlock(&dep->rwmtx);
 }
 
 ERTS_GLB_INLINE void
-erts_smp_de_links_lock(DistEntry *dep)
+erts_de_links_lock(DistEntry *dep)
 {
-    erts_smp_mtx_lock(&dep->lnk_mtx);
+    erts_mtx_lock(&dep->lnk_mtx);
 }
 
 ERTS_GLB_INLINE void
-erts_smp_de_links_unlock(DistEntry *dep)
+erts_de_links_unlock(DistEntry *dep)
 {
-    erts_smp_mtx_unlock(&dep->lnk_mtx);
+    erts_mtx_unlock(&dep->lnk_mtx);
 }
 
 #endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
 void erts_debug_test_node_tab_delayed_delete(Sint64 millisecs);
+void erts_lcnt_update_distribution_locks(int enable);
 
 #endif
diff --git a/erts/emulator/beam/erl_port.h b/erts/emulator/beam/erl_port.h
index b64de624dd..9117eb1f72 100644
--- a/erts/emulator/beam/erl_port.h
+++ b/erts/emulator/beam/erl_port.h
@@ -119,9 +119,7 @@ typedef struct {
     void *data[ERTS_PRTSD_SIZE];
 } ErtsPrtSD;
 
-#ifdef ERTS_SMP
 typedef struct ErtsXPortsList_ ErtsXPortsList;
-#endif
 
 /*
  * Port locking:
@@ -146,17 +144,12 @@ struct _erl_drv_port {
 
     ErtsPortTaskSched sched;
     ErtsPortTaskHandle timeout_task;
-#ifdef ERTS_SMP
     erts_mtx_t *lock;
     ErtsXPortsList *xports;
-    erts_smp_atomic_t run_queue;
-#else
-    erts_atomic32_t refc;
-    int cleanup;
-#endif
+    erts_atomic_t run_queue;
     erts_atomic_t connected;	/* A connected process */
     Eterm caller;		/* Current caller. */
-    erts_smp_atomic_t data;	/* Data associated with port. */
+    erts_atomic_t data;	/* Data associated with port. */
     Uint bytes_in;		/* Number of bytes read */
     Uint bytes_out;		/* Number of bytes written */
 
@@ -173,7 +166,7 @@ struct _erl_drv_port {
     int control_flags;		 /* Flags for port_control()  */
     ErlDrvPDL port_data_lock;
 
-    erts_smp_atomic_t psd;	 /* Port specific data */
+    erts_atomic_t psd;	 /* Port specific data */
     int reds; /* Only used while executing driver callbacks */
 
     struct {
@@ -209,24 +202,20 @@ ERTS_GLB_INLINE ErtsRunQueue *erts_port_runq(Port *prt);
 ERTS_GLB_INLINE ErtsRunQueue *
 erts_port_runq(Port *prt)
 {
-#ifdef ERTS_SMP
     ErtsRunQueue *rq1, *rq2;
-    rq1 = (ErtsRunQueue *) erts_smp_atomic_read_nob(&prt->run_queue);
+    rq1 = (ErtsRunQueue *) erts_atomic_read_nob(&prt->run_queue);
     if (!rq1)
 	return NULL;
     while (1) {
-	erts_smp_runq_lock(rq1);
-	rq2 = (ErtsRunQueue *) erts_smp_atomic_read_nob(&prt->run_queue);
+	erts_runq_lock(rq1);
+	rq2 = (ErtsRunQueue *) erts_atomic_read_nob(&prt->run_queue);
 	if (rq1 == rq2)
 	    return rq1;
-	erts_smp_runq_unlock(rq1);
+	erts_runq_unlock(rq1);
 	rq1 = rq2;
 	if (!rq1)
 	    return NULL;
     }
-#else
-    return ERTS_RUNQ_IX(0);
-#endif
 }
 
 #endif
@@ -240,10 +229,10 @@ ERTS_GLB_INLINE void *erts_prtsd_set(Port *p, int ix, void *new);
 ERTS_GLB_INLINE void *
 erts_prtsd_get(Port *prt, int ix)
 {
-    ErtsPrtSD *psd = (ErtsPrtSD *) erts_smp_atomic_read_nob(&prt->psd);
+    ErtsPrtSD *psd = (ErtsPrtSD *) erts_atomic_read_nob(&prt->psd);
     if (!psd)
 	return NULL;
-    ERTS_SMP_DATA_DEPENDENCY_READ_MEMORY_BARRIER;
+    ERTS_THR_DATA_DEPENDENCY_READ_MEMORY_BARRIER;
     return psd->data[ix];
 }
 
@@ -254,16 +243,14 @@ erts_prtsd_set(Port *prt, int ix, void *data)
     void *old;
     int i;
 
-    psd = (ErtsPrtSD *) erts_smp_atomic_read_nob(&prt->psd);
+    psd = (ErtsPrtSD *) erts_atomic_read_nob(&prt->psd);
 
     if (psd) {
-#ifdef ERTS_SMP
 #ifdef ETHR_ORDERED_READ_DEPEND
 	ETHR_MEMBAR(ETHR_LoadStore|ETHR_StoreStore);
 #else
 	ETHR_MEMBAR(ETHR_LoadLoad|ETHR_LoadStore|ETHR_StoreStore);
 #endif
-#endif
 	old = psd->data[ix];
 	psd->data[ix] = data;
 	return old;
@@ -275,7 +262,7 @@ erts_prtsd_set(Port *prt, int ix, void *data)
     new_psd = erts_alloc(ERTS_ALC_T_PRTSD, sizeof(ErtsPrtSD));
     for (i = 0; i < ERTS_PRTSD_SIZE; i++)
 	new_psd->data[i] = NULL;
-    psd = (ErtsPrtSD *) erts_smp_atomic_cmpxchg_mb(&prt->psd,
+    psd = (ErtsPrtSD *) erts_atomic_cmpxchg_mb(&prt->psd,
 						   (erts_aint_t) new_psd,
 						   (erts_aint_t) NULL);
     if (psd)
@@ -359,15 +346,10 @@ Eterm erts_request_io_bytes(Process *c_p);
 
 void print_port_info(Port *, fmtfn_t, void *);
 void erts_port_free(Port *);
-#ifndef ERTS_SMP
-void erts_port_cleanup(Port *);
-#endif
 void erts_fire_port_monitor(Port *prt, Eterm ref);
-#ifdef ERTS_SMP
 int erts_port_handle_xports(Port *);
-#endif
 
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
 int erts_lc_is_port_locked(Port *);
 #endif
 
@@ -376,9 +358,9 @@ ERTS_GLB_INLINE void erts_port_dec_refc(Port *prt);
 ERTS_GLB_INLINE void erts_port_add_refc(Port *prt, Sint32 add_refc);
 ERTS_GLB_INLINE Sint erts_port_read_refc(Port *prt);
 
-ERTS_GLB_INLINE int erts_smp_port_trylock(Port *prt);
-ERTS_GLB_INLINE void erts_smp_port_lock(Port *prt);
-ERTS_GLB_INLINE void erts_smp_port_unlock(Port *prt);
+ERTS_GLB_INLINE int erts_port_trylock(Port *prt);
+ERTS_GLB_INLINE void erts_port_lock(Port *prt);
+ERTS_GLB_INLINE void erts_port_unlock(Port *prt);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
@@ -407,35 +389,27 @@ ERTS_GLB_INLINE Sint erts_port_read_refc(Port *prt)
 }
 
 ERTS_GLB_INLINE int
-erts_smp_port_trylock(Port *prt)
+erts_port_trylock(Port *prt)
 {
-#ifdef ERTS_SMP
     /* *Need* to be a managed thread */
-    ERTS_SMP_LC_ASSERT(erts_thr_progress_is_managed_thread());
+    ERTS_LC_ASSERT(erts_thr_progress_is_managed_thread());
     return erts_mtx_trylock(prt->lock);
-#else
-    return 0;
-#endif
 }
 
 ERTS_GLB_INLINE void
-erts_smp_port_lock(Port *prt)
+erts_port_lock(Port *prt)
 {
-#ifdef ERTS_SMP
     /* *Need* to be a managed thread */
-    ERTS_SMP_LC_ASSERT(erts_thr_progress_is_managed_thread());
+    ERTS_LC_ASSERT(erts_thr_progress_is_managed_thread());
     erts_mtx_lock(prt->lock);
-#endif
 }
 
 ERTS_GLB_INLINE void
-erts_smp_port_unlock(Port *prt)
+erts_port_unlock(Port *prt)
 {
-#ifdef ERTS_SMP
     /* *Need* to be a managed thread */
-    ERTS_SMP_LC_ASSERT(erts_thr_progress_is_managed_thread());
+    ERTS_LC_ASSERT(erts_thr_progress_is_managed_thread());
     erts_mtx_unlock(prt->lock);
-#endif
 }
 
 #endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
@@ -466,9 +440,7 @@ extern const Port erts_invalid_port;
 int erts_is_port_ioq_empty(Port *);
 void erts_terminate_port(Port *);
 
-#ifdef ERTS_SMP
 Port *erts_de2port(DistEntry *, Process *, ErtsProcLocks);
-#endif
 
 ERTS_GLB_INLINE Port *erts_pix2port(int);
 ERTS_GLB_INLINE Port *erts_port_lookup_raw(Eterm);
@@ -476,11 +448,9 @@ ERTS_GLB_INLINE Port *erts_port_lookup(Eterm, Uint32);
 ERTS_GLB_INLINE Port*erts_id2port(Eterm id);
 ERTS_GLB_INLINE Port *erts_id2port_sflgs(Eterm, Process *, ErtsProcLocks, Uint32);
 ERTS_GLB_INLINE void erts_port_release(Port *);
-#ifdef ERTS_SMP
 ERTS_GLB_INLINE Port *erts_thr_port_lookup(Eterm id, Uint32 invalid_sflgs);
 ERTS_GLB_INLINE Port *erts_thr_id2port_sflgs(Eterm id, Uint32 invalid_sflgs);
 ERTS_GLB_INLINE void erts_thr_port_release(Port *prt);
-#endif
 ERTS_GLB_INLINE Port *erts_thr_drvport2port(ErlDrvPort, int);
 ERTS_GLB_INLINE Port *erts_drvport2port_state(ErlDrvPort, erts_aint32_t *);
 ERTS_GLB_INLINE Eterm erts_drvport2id(ErlDrvPort);
@@ -506,7 +476,7 @@ erts_port_lookup_raw(Eterm id)
 {
     Port *prt;
 
-    ERTS_SMP_LC_ASSERT(erts_thr_progress_lc_is_delaying());
+    ERTS_LC_ASSERT(erts_thr_progress_lc_is_delaying());
 
     if (is_not_internal_port(id))
 	return NULL;
@@ -535,7 +505,7 @@ erts_id2port(Eterm id)
     Port *prt;
 
     /* Only allowed to be called from managed threads */
-    ERTS_SMP_LC_ASSERT(erts_thr_progress_is_managed_thread());
+    ERTS_LC_ASSERT(erts_thr_progress_is_managed_thread());
 
     if (is_not_internal_port(id))
 	return NULL;
@@ -546,10 +516,10 @@ erts_id2port(Eterm id)
     if (!prt || prt->common.id != id)
 	return NULL;
 
-    erts_smp_port_lock(prt);
+    erts_port_lock(prt);
     state = erts_atomic32_read_nob(&prt->state);
     if (state & ERTS_PORT_SFLGS_INVALID_LOOKUP) {
-	erts_smp_port_unlock(prt);
+	erts_port_unlock(prt);
 	return NULL;
     }
 
@@ -562,14 +532,12 @@ erts_id2port_sflgs(Eterm id,
 		   Process *c_p, ErtsProcLocks c_p_locks,
 		   Uint32 invalid_sflgs)
 {
-#ifdef ERTS_SMP
     int no_proc_locks = !c_p || !c_p_locks;
-#endif
     erts_aint32_t state;
     Port *prt;
 
     /* Only allowed to be called from managed threads */
-    ERTS_SMP_LC_ASSERT(erts_thr_progress_is_managed_thread());
+    ERTS_LC_ASSERT(erts_thr_progress_is_managed_thread());
 
     if (is_not_internal_port(id))
 	return NULL;
@@ -580,21 +548,17 @@ erts_id2port_sflgs(Eterm id,
     if (!prt || prt->common.id != id)
 	return NULL;
 
-#ifdef ERTS_SMP
     if (no_proc_locks)
-	erts_smp_port_lock(prt);
-    else if (erts_smp_port_trylock(prt) == EBUSY) {
+	erts_port_lock(prt);
+    else if (erts_port_trylock(prt) == EBUSY) {
 	/* Unlock process locks, and acquire locks in lock order... */
-	erts_smp_proc_unlock(c_p, c_p_locks);
-	erts_smp_port_lock(prt);
-	erts_smp_proc_lock(c_p, c_p_locks);
+	erts_proc_unlock(c_p, c_p_locks);
+	erts_port_lock(prt);
+	erts_proc_lock(c_p, c_p_locks);
     }
-#endif
     state = erts_atomic32_read_nob(&prt->state);
     if (state & invalid_sflgs) {
-#ifdef ERTS_SMP
-	erts_smp_port_unlock(prt);
-#endif
+	erts_port_unlock(prt);
 	return NULL;
     }
 
@@ -605,18 +569,10 @@ ERTS_GLB_INLINE void
 erts_port_release(Port *prt)
 {
     /* Only allowed to be called from managed threads */
-    ERTS_SMP_LC_ASSERT(erts_thr_progress_is_managed_thread());
-#ifdef ERTS_SMP
-    erts_smp_port_unlock(prt);
-#else
-    if (prt->cleanup) {
-	prt->cleanup = 0;
-	erts_port_cleanup(prt);
-    }
-#endif
+    ERTS_LC_ASSERT(erts_thr_progress_is_managed_thread());
+    erts_port_unlock(prt);
 }
 
-#ifdef ERTS_SMP
 /*
  * erts_thr_id2port_sflgs() and erts_port_dec_refc(prt) can
  * be used by unmanaged threads in the SMP case.
@@ -702,13 +658,10 @@ ERTS_GLB_INLINE void
 erts_thr_port_release(Port *prt)
 {
     erts_mtx_unlock(prt->lock);
-#ifdef ERTS_SMP
     if (!erts_thr_progress_is_managed_thread())
 	erts_port_dec_refc(prt);
-#endif
 }
 
-#endif
 
 ERTS_GLB_INLINE Port *
 erts_thr_drvport2port(ErlDrvPort drvport, int lock_pdl)
@@ -724,7 +677,7 @@ erts_thr_drvport2port(ErlDrvPort drvport, int lock_pdl)
 #ifdef ERTS_ENABLE_LOCK_CHECK
     if (!ERTS_IS_CRASH_DUMPING) {
 	if (erts_lc_is_emu_thr()) {
-	    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+	    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 	    ERTS_LC_ASSERT(!prt->port_data_lock
 			   || erts_lc_mtx_is_locked(&prt->port_data_lock->mtx));
 	}
@@ -753,7 +706,7 @@ erts_drvport2port_state(ErlDrvPort drvport, erts_aint32_t *statep)
 //    ERTS_LC_ASSERT(erts_lc_is_emu_thr());
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return ERTS_INVALID_ERL_DRV_PORT;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt)
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt)
 		       || ERTS_IS_CRASH_DUMPING);
     /* 
      * This state check is only needed since a driver callback
@@ -810,23 +763,21 @@ erts_port_driver_callback_epilogue(Port *prt, erts_aint32_t *statep)
     int reds = 0;
     erts_aint32_t state;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
     state = erts_atomic32_read_nob(&prt->state);
     if ((state & ERTS_PORT_SFLG_CLOSING) && erts_is_port_ioq_empty(prt)) {
 	reds += ERTS_PORT_REDS_TERMINATE;
 	erts_terminate_port(prt);
 	state = erts_atomic32_read_nob(&prt->state);
-	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+	ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
     }
 
-#ifdef ERTS_SMP
     if (prt->xports) {
 	reds += erts_port_handle_xports(prt);
-	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+	ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 	ASSERT(!prt->xports);
     }
-#endif
 
     if (statep)
 	*statep = state;
diff --git a/erts/emulator/beam/erl_port_task.c b/erts/emulator/beam/erl_port_task.c
index 4d7a86398a..a588477320 100644
--- a/erts/emulator/beam/erl_port_task.c
+++ b/erts/emulator/beam/erl_port_task.c
@@ -36,6 +36,7 @@
 #include "erl_check_io.h"
 #include "dtrace-wrapper.h"
 #include "lttng-wrapper.h"
+#include "erl_check_io.h"
 #include <stdarg.h>
 
 /*
@@ -83,15 +84,13 @@ static void chk_task_queues(Port *pp, ErtsPortTask *execq, int processing_busy_q
 #define LTTNG_DRIVER(TRACEPOINT, PP) do {} while(0)
 #endif
 
-#define ERTS_SMP_LC_VERIFY_RQ(RQ, PP)					\
+#define ERTS_LC_VERIFY_RQ(RQ, PP)					\
     do {								\
-	ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(runq));		\
-	ERTS_SMP_LC_ASSERT((RQ) == ((ErtsRunQueue *)			\
-				    erts_smp_atomic_read_nob(&(PP)->run_queue))); \
+	ERTS_LC_ASSERT(erts_lc_runq_is_locked(runq));		\
+	ERTS_LC_ASSERT((RQ) == ((ErtsRunQueue *)			\
+				    erts_atomic_read_nob(&(PP)->run_queue))); \
     } while (0)
 
-erts_smp_atomic_t erts_port_task_outstanding_io_tasks;
-
 #define ERTS_PT_STATE_SCHEDULED		0
 #define ERTS_PT_STATE_ABORTED		1
 #define ERTS_PT_STATE_EXECUTING		2
@@ -99,7 +98,6 @@ erts_smp_atomic_t erts_port_task_outstanding_io_tasks;
 typedef union {
     struct { /* I/O tasks */
 	ErlDrvEvent event;
-	ErlDrvEventData event_data;
     } io;
     struct {
 	ErtsProc2PortSigCallback callback;
@@ -108,7 +106,7 @@ typedef union {
 } ErtsPortTaskTypeData;
 
 struct ErtsPortTask_ {
-    erts_smp_atomic32_t state;
+    erts_atomic32_t state;
     ErtsPortTaskType type;
     union {
 	struct {
@@ -126,9 +124,7 @@ struct ErtsPortTaskHandleList_ {
     ErtsPortTaskHandle handle;
     union {
 	ErtsPortTaskHandleList *next;
-#ifdef ERTS_SMP
 	ErtsThrPrgrLaterOp release;
-#endif
     } u;
 };
 
@@ -151,35 +147,29 @@ static void begin_port_cleanup(Port *pp,
 			       ErtsPortTask **execq,
 			       int *processing_busy_q_p);
 
-ERTS_SCHED_PREF_QUICK_ALLOC_IMPL(port_task,
-				 ErtsPortTask,
-				 1000,
-				 ERTS_ALC_T_PORT_TASK)
+ERTS_THR_PREF_QUICK_ALLOC_IMPL(port_task,
+                               ErtsPortTask,
+                               1000,
+                               ERTS_ALC_T_PORT_TASK)
 
 ERTS_SCHED_PREF_QUICK_ALLOC_IMPL(busy_caller_table,
 				 ErtsPortTaskBusyCallerTable,
 				 50,
 				 ERTS_ALC_T_BUSY_CALLER_TAB)
 
-#ifdef ERTS_SMP
 static void
 call_port_task_free(void *vptp)
 {
     port_task_free((ErtsPortTask *) vptp);
 }
-#endif
 
 static ERTS_INLINE void
 schedule_port_task_free(ErtsPortTask *ptp)
 {
-#ifdef ERTS_SMP
     erts_schedule_thr_prgr_later_cleanup_op(call_port_task_free,
 					    (void *) ptp,
 					    &ptp->u.release,
 					    sizeof(ErtsPortTask));
-#else
-    port_task_free(ptp);
-#endif
 }
 
 static ERTS_INLINE ErtsPortTask *
@@ -199,7 +189,7 @@ p2p_sig_data_init(ErtsPortTask *ptp)
 
     ptp->type = ERTS_PORT_TASK_PROC_SIG;
     ptp->u.alive.flags = ERTS_PT_FLG_SIG_DEP;
-    erts_smp_atomic32_init_nob(&ptp->state, ERTS_PT_STATE_SCHEDULED);
+    erts_atomic32_init_nob(&ptp->state, ERTS_PT_STATE_SCHEDULED);
 
     ASSERT(ptp == p2p_sig_data_to_task(&ptp->u.alive.td.psig.data));
 
@@ -290,7 +280,7 @@ popped_from_busy_queue(Port *pp, ErtsPortTask *ptp, int last)
 #ifdef DEBUG
 	    erts_aint32_t flags =
 #endif
-		erts_smp_atomic32_read_band_nob(
+		erts_atomic32_read_band_nob(
 		    &pp->sched.flags,
 		    ~ERTS_PTS_FLG_HAVE_BUSY_TASKS);
 	    ASSERT(flags & ERTS_PTS_FLG_HAVE_BUSY_TASKS);
@@ -337,7 +327,7 @@ busy_wait_move_to_busy_queue(Port *pp, ErtsPortTask *ptp)
 #ifdef DEBUG
 	flags = 
 #endif
-	    erts_smp_atomic32_read_bor_nob(&pp->sched.flags,
+	    erts_atomic32_read_bor_nob(&pp->sched.flags,
 					   ERTS_PTS_FLG_HAVE_BUSY_TASKS);
 	ASSERT(!(flags & ERTS_PTS_FLG_HAVE_BUSY_TASKS));
 
@@ -477,7 +467,7 @@ no_sig_dep_move_from_busyq(Port *pp)
 	int bix;
 	erts_aint32_t flags =
 #endif
-	    erts_smp_atomic32_read_band_nob(
+	    erts_atomic32_read_band_nob(
 		&pp->sched.flags,
 		~ERTS_PTS_FLG_HAVE_BUSY_TASKS);
 	ASSERT(flags & ERTS_PTS_FLG_HAVE_BUSY_TASKS);
@@ -510,11 +500,11 @@ chk_task_queues(Port *pp, ErtsPortTask *execq, int processing_busy_queue)
     if (!first) {
 	ASSERT(!tabp);
 	ASSERT(!pp->sched.taskq.local.busy.last);
-	ASSERT(!(erts_smp_atomic32_read_nob(&pp->sched.flags) & ERTS_PTS_FLG_HAVE_BUSY_TASKS));
+	ASSERT(!(erts_atomic32_read_nob(&pp->sched.flags) & ERTS_PTS_FLG_HAVE_BUSY_TASKS));
 	return;
     }
 
-    ASSERT(erts_smp_atomic32_read_nob(&pp->sched.flags) & ERTS_PTS_FLG_HAVE_BUSY_TASKS);
+    ASSERT(erts_atomic32_read_nob(&pp->sched.flags) & ERTS_PTS_FLG_HAVE_BUSY_TASKS);
     ASSERT(tabp);
 
     tot_count = 0;
@@ -570,13 +560,13 @@ chk_task_queues(Port *pp, ErtsPortTask *execq, int processing_busy_queue)
 static ERTS_INLINE void
 reset_port_task_handle(ErtsPortTaskHandle *pthp)
 {
-    erts_smp_atomic_set_relb(pthp, (erts_aint_t) NULL);
+    erts_atomic_set_relb(pthp, (erts_aint_t) NULL);
 }
 
 static ERTS_INLINE ErtsPortTask *
 handle2task(ErtsPortTaskHandle *pthp)
 {
-    return (ErtsPortTask *) erts_smp_atomic_read_acqb(pthp);
+    return (ErtsPortTask *) erts_atomic_read_acqb(pthp);
 }
 
 static ERTS_INLINE void
@@ -593,8 +583,9 @@ reset_executed_io_task_handle(ErtsPortTask *ptp)
 {
     if (ptp->u.alive.handle) {
 	ASSERT(ptp == handle2task(ptp->u.alive.handle));
-	erts_io_notify_port_task_executed(ptp->u.alive.handle);
-	reset_port_task_handle(ptp->u.alive.handle);
+        /* The port task handle is reset inside task_executed */
+	erts_io_notify_port_task_executed(ptp->type, ptp->u.alive.handle,
+                                          reset_port_task_handle);
     }
 }
 
@@ -603,7 +594,7 @@ set_handle(ErtsPortTask *ptp, ErtsPortTaskHandle *pthp)
 {
     ptp->u.alive.handle = pthp;
     if (pthp) {
-	erts_smp_atomic_set_relb(pthp, (erts_aint_t) ptp);
+	erts_atomic_set_relb(pthp, (erts_aint_t) ptp);
 	ASSERT(ptp == handle2task(ptp->u.alive.handle));
     }
 }
@@ -617,7 +608,7 @@ set_tmp_handle(ErtsPortTask *ptp, ErtsPortTaskHandle *pthp)
 	 * IMPORTANT! Task either need to be aborted, or task handle
 	 * need to be detached before thread progress has been made.
 	 */
-	erts_smp_atomic_set_relb(pthp, (erts_aint_t) ptp);
+	erts_atomic_set_relb(pthp, (erts_aint_t) ptp);
     }
 }
 
@@ -635,20 +626,20 @@ check_unset_busy_port_q(Port *pp,
     int resume_procs = 0;
 
     ASSERT(bpq);
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(pp));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(pp));
 
     erts_port_task_sched_lock(&pp->sched);
-    qsize = (ErlDrvSizeT) erts_smp_atomic_read_nob(&bpq->size);
-    low = (ErlDrvSizeT) erts_smp_atomic_read_nob(&bpq->low);
+    qsize = (ErlDrvSizeT) erts_atomic_read_nob(&bpq->size);
+    low = (ErlDrvSizeT) erts_atomic_read_nob(&bpq->low);
     if (qsize < low) {
 	erts_aint32_t mask = ~(ERTS_PTS_FLG_CHK_UNSET_BUSY_PORT_Q
 			       | ERTS_PTS_FLG_BUSY_PORT_Q);
-	flags = erts_smp_atomic32_read_band_relb(&pp->sched.flags, mask);
+	flags = erts_atomic32_read_band_relb(&pp->sched.flags, mask);
 	if ((flags & ERTS_PTS_FLGS_BUSY) == ERTS_PTS_FLG_BUSY_PORT_Q)
 	    resume_procs = 1;
     }
     else if (flags & ERTS_PTS_FLG_CHK_UNSET_BUSY_PORT_Q) {
-	flags = erts_smp_atomic32_read_band_relb(&pp->sched.flags,
+	flags = erts_atomic32_read_band_relb(&pp->sched.flags,
 						 ~ERTS_PTS_FLG_CHK_UNSET_BUSY_PORT_Q);
 	flags &= ~ERTS_PTS_FLG_CHK_UNSET_BUSY_PORT_Q;
     }
@@ -673,16 +664,16 @@ aborted_proc2port_data(Port *pp, ErlDrvSizeT size)
 
     bpq = pp->sched.taskq.bpq;
 
-    qsz = (ErlDrvSizeT) erts_smp_atomic_add_read_acqb(&bpq->size,
+    qsz = (ErlDrvSizeT) erts_atomic_add_read_acqb(&bpq->size,
 						      (erts_aint_t) -size);
     ASSERT(qsz + size > qsz);
-    flags = erts_smp_atomic32_read_nob(&pp->sched.flags);
+    flags = erts_atomic32_read_nob(&pp->sched.flags);
     ASSERT(pp->sched.taskq.bpq);
     if ((flags & (ERTS_PTS_FLG_CHK_UNSET_BUSY_PORT_Q
 		  | ERTS_PTS_FLG_BUSY_PORT_Q)) != ERTS_PTS_FLG_BUSY_PORT_Q)
 	return;
-    if (qsz < (ErlDrvSizeT) erts_smp_atomic_read_nob(&bpq->low))
-	erts_smp_atomic32_read_bor_nob(&pp->sched.flags,
+    if (qsz < (ErlDrvSizeT) erts_atomic_read_nob(&bpq->low))
+	erts_atomic32_read_bor_nob(&pp->sched.flags,
 				       ERTS_PTS_FLG_CHK_UNSET_BUSY_PORT_Q);
 }
 
@@ -700,13 +691,13 @@ dequeued_proc2port_data(Port *pp, ErlDrvSizeT size)
 
     bpq = pp->sched.taskq.bpq;
 
-    qsz = (ErlDrvSizeT) erts_smp_atomic_add_read_acqb(&bpq->size,
+    qsz = (ErlDrvSizeT) erts_atomic_add_read_acqb(&bpq->size,
 						      (erts_aint_t) -size);
     ASSERT(qsz + size > qsz);
-    flags = erts_smp_atomic32_read_nob(&pp->sched.flags);
+    flags = erts_atomic32_read_nob(&pp->sched.flags);
     if (!(flags & ERTS_PTS_FLG_BUSY_PORT_Q))
 	return;
-    if (qsz < (ErlDrvSizeT) erts_smp_atomic_read_acqb(&bpq->low))
+    if (qsz < (ErlDrvSizeT) erts_atomic_read_acqb(&bpq->low))
 	check_unset_busy_port_q(pp, flags, bpq);
 }
 
@@ -719,19 +710,19 @@ enqueue_proc2port_data(Port *pp,
     if (sigdp && bpq) {
 	ErlDrvSizeT size = erts_proc2port_sig_command_data_size(sigdp);
 	if (size) {
-	    erts_aint_t asize = erts_smp_atomic_add_read_acqb(&bpq->size,
+	    erts_aint_t asize = erts_atomic_add_read_acqb(&bpq->size,
 							      (erts_aint_t) size);
 	    ErlDrvSizeT qsz = (ErlDrvSizeT) asize;
 
 	    ASSERT(qsz - size < qsz);
 
 	    if (!(flags & ERTS_PTS_FLG_BUSY_PORT_Q) && qsz > bpq->high) {
-		flags = erts_smp_atomic32_read_bor_acqb(&pp->sched.flags,
+		flags = erts_atomic32_read_bor_acqb(&pp->sched.flags,
 							ERTS_PTS_FLG_BUSY_PORT_Q);
 		flags |= ERTS_PTS_FLG_BUSY_PORT_Q;
-		qsz = (ErlDrvSizeT) erts_smp_atomic_read_acqb(&bpq->size);
-		if (qsz < (ErlDrvSizeT) erts_smp_atomic_read_nob(&bpq->low)) {
-		    flags = (erts_smp_atomic32_read_bor_relb(
+		qsz = (ErlDrvSizeT) erts_atomic_read_acqb(&bpq->size);
+		if (qsz < (ErlDrvSizeT) erts_atomic_read_nob(&bpq->low)) {
+		    flags = (erts_atomic32_read_bor_relb(
 				 &pp->sched.flags,
 				 ERTS_PTS_FLG_CHK_UNSET_BUSY_PORT_Q));
 		    flags |= ERTS_PTS_FLG_CHK_UNSET_BUSY_PORT_Q;
@@ -779,18 +770,18 @@ erl_drv_busy_msgq_limits(ErlDrvPort dport, ErlDrvSizeT *lowp, ErlDrvSizeT *highp
 	erts_aint32_t flags;
 	pp->sched.taskq.bpq = NULL;
 	flags = ~(ERTS_PTS_FLG_BUSY_PORT_Q|ERTS_PTS_FLG_CHK_UNSET_BUSY_PORT_Q);
-	flags = erts_smp_atomic32_read_band_acqb(&pp->sched.flags, flags);
+	flags = erts_atomic32_read_band_acqb(&pp->sched.flags, flags);
 	if ((flags & ERTS_PTS_FLGS_BUSY) == ERTS_PTS_FLG_BUSY_PORT_Q)
 	    resume_procs = 1;
     }
     else {
 
 	if (!low)
-	    low = (ErlDrvSizeT) erts_smp_atomic_read_nob(&bpq->low);
+	    low = (ErlDrvSizeT) erts_atomic_read_nob(&bpq->low);
 	else {
 	    if (bpq->high < low)
 		bpq->high = low;
-	    erts_smp_atomic_set_relb(&bpq->low, (erts_aint_t) low);
+	    erts_atomic_set_relb(&bpq->low, (erts_aint_t) low);
 	    written = 1;
 	}
     
@@ -799,19 +790,19 @@ erl_drv_busy_msgq_limits(ErlDrvPort dport, ErlDrvSizeT *lowp, ErlDrvSizeT *highp
 	else {
 	    if (low > high) {
 		low = high;
-		erts_smp_atomic_set_relb(&bpq->low, (erts_aint_t) low);
+		erts_atomic_set_relb(&bpq->low, (erts_aint_t) low);
 	    }
 	    bpq->high = high;
 	    written = 1;
 	}
 
 	if (written) {
-	    ErlDrvSizeT size = (ErlDrvSizeT) erts_smp_atomic_read_nob(&bpq->size);
+	    ErlDrvSizeT size = (ErlDrvSizeT) erts_atomic_read_nob(&bpq->size);
 	    if (size > high)
-		erts_smp_atomic32_read_bor_relb(&pp->sched.flags,
+		erts_atomic32_read_bor_relb(&pp->sched.flags,
 						ERTS_PTS_FLG_BUSY_PORT_Q);
 	    else if (size < low)
-		erts_smp_atomic32_read_bor_relb(&pp->sched.flags,
+		erts_atomic32_read_bor_relb(&pp->sched.flags,
 						ERTS_PTS_FLG_CHK_UNSET_BUSY_PORT_Q);
 	}
     }
@@ -830,25 +821,19 @@ erl_drv_busy_msgq_limits(ErlDrvPort dport, ErlDrvSizeT *lowp, ErlDrvSizeT *highp
  * No-suspend handles.
  */
 
-#ifdef ERTS_SMP
 static void
 free_port_task_handle_list(void *vpthlp)
 {
     erts_free(ERTS_ALC_T_PT_HNDL_LIST, vpthlp);
 }
-#endif
 
 static void
 schedule_port_task_handle_list_free(ErtsPortTaskHandleList *pthlp)
 {
-#ifdef ERTS_SMP
     erts_schedule_thr_prgr_later_cleanup_op(free_port_task_handle_list,
 					    (void *) pthlp,
 					    &pthlp->u.release,
 					    sizeof(ErtsPortTaskHandleList));
-#else
-    erts_free(ERTS_ALC_T_PT_HNDL_LIST, pthlp);
-#endif
 }
 
 static ERTS_INLINE void
@@ -891,7 +876,7 @@ get_free_nosuspend_handles(Port *pp)
 {
     ErtsPortTaskHandleList *nshp, *last_nshp = NULL;
 
-    ERTS_SMP_LC_ASSERT(erts_port_task_sched_lock_is_locked(&pp->sched));
+    ERTS_LC_ASSERT(erts_port_task_sched_lock_is_locked(&pp->sched));
 
     nshp = pp->sched.taskq.local.busy.nosuspend;
 
@@ -907,7 +892,7 @@ get_free_nosuspend_handles(Port *pp)
 	pp->sched.taskq.local.busy.nosuspend = last_nshp->u.next;
 	last_nshp->u.next = NULL;
 	if (!pp->sched.taskq.local.busy.nosuspend)
-	    erts_smp_atomic32_read_band_nob(&pp->sched.flags,
+	    erts_atomic32_read_band_nob(&pp->sched.flags,
 					    ~ERTS_PTS_FLG_HAVE_NS_TASKS);
     }
     return nshp;
@@ -930,7 +915,7 @@ free_nosuspend_handles(ErtsPortTaskHandleList *free_nshp)
 static ERTS_INLINE void
 enqueue_port(ErtsRunQueue *runq, Port *pp)
 {
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(runq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(runq));
     pp->sched.next = NULL;
     if (runq->ports.end) {
 	ASSERT(runq->ports.start);
@@ -944,19 +929,17 @@ enqueue_port(ErtsRunQueue *runq, Port *pp)
     runq->ports.end = pp;
     ASSERT(runq->ports.start && runq->ports.end);
 
-    erts_smp_inc_runq_len(runq, &runq->ports.info, ERTS_PORT_PRIO_LEVEL);
+    erts_inc_runq_len(runq, &runq->ports.info, ERTS_PORT_PRIO_LEVEL);
 
-#ifdef ERTS_SMP
     if (ERTS_RUNQ_FLGS_GET_NOB(runq) & ERTS_RUNQ_FLG_HALTING)
 	erts_non_empty_runq(runq);
-#endif
 }
 
 static ERTS_INLINE Port *
 pop_port(ErtsRunQueue *runq)
 {
     Port *pp = runq->ports.start;
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(runq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(runq));
     if (!pp) {
 	ASSERT(!runq->ports.end);
     }
@@ -966,7 +949,7 @@ pop_port(ErtsRunQueue *runq)
 	    ASSERT(runq->ports.end == pp);
 	    runq->ports.end = NULL;
 	}
-	erts_smp_dec_runq_len(runq, &runq->ports.info, ERTS_PORT_PRIO_LEVEL);
+	erts_dec_runq_len(runq, &runq->ports.info, ERTS_PORT_PRIO_LEVEL);
     }
 
     ASSERT(runq->ports.start || !runq->ports.end);
@@ -993,7 +976,7 @@ enqueue_task(Port *pp,
     if (ns_pthlp)
 	fail_flags |= ERTS_PTS_FLG_BUSY_PORT;
     erts_port_task_sched_lock(&pp->sched);
-    flags = erts_smp_atomic32_read_nob(&pp->sched.flags);
+    flags = erts_atomic32_read_nob(&pp->sched.flags);
     if (flags & fail_flags)
 	res = 0;
     else {
@@ -1024,7 +1007,7 @@ enqueue_task(Port *pp,
 static ERTS_INLINE void
 prepare_exec(Port *pp, ErtsPortTask **execqp, int *processing_busy_q_p)
 {
-    erts_aint32_t act = erts_smp_atomic32_read_nob(&pp->sched.flags);
+    erts_aint32_t act = erts_atomic32_read_nob(&pp->sched.flags);
 
     if (!pp->sched.taskq.local.busy.first || (act & ERTS_PTS_FLG_BUSY_PORT)) {
 	*execqp = pp->sched.taskq.local.first;
@@ -1045,7 +1028,7 @@ prepare_exec(Port *pp, ErtsPortTask **execqp, int *processing_busy_q_p)
 	new &= ~ERTS_PTS_FLG_IN_RUNQ;
 	new |= ERTS_PTS_FLG_EXEC;
 
-	act = erts_smp_atomic32_cmpxchg_nob(&pp->sched.flags, new, exp);
+	act = erts_atomic32_cmpxchg_nob(&pp->sched.flags, new, exp);
 
 	ASSERT(act & ERTS_PTS_FLG_IN_RUNQ);
 
@@ -1072,7 +1055,7 @@ finalize_exec(Port *pp, ErtsPortTask **execq, int processing_busy_q)
 
     *execq = NULL;
 
-    act = erts_smp_atomic32_read_nob(&pp->sched.flags);
+    act = erts_atomic32_read_nob(&pp->sched.flags);
     if (act & ERTS_PTS_FLG_CHK_UNSET_BUSY_PORT_Q)
 	act = check_unset_busy_port_q(pp, act, pp->sched.taskq.bpq);
 
@@ -1089,7 +1072,7 @@ finalize_exec(Port *pp, ErtsPortTask **execq, int processing_busy_q)
 	if (act & ERTS_PTS_FLG_HAVE_TASKS)
 	    new |= ERTS_PTS_FLG_IN_RUNQ;
 
-	act = erts_smp_atomic32_cmpxchg_relb(&pp->sched.flags, new, exp);
+	act = erts_atomic32_cmpxchg_relb(&pp->sched.flags, new, exp);
 
 	ERTS_LC_ASSERT(!(act & ERTS_PTS_FLG_IN_RUNQ));
 	ERTS_LC_ASSERT(!(act & ERTS_PTS_FLG_EXEC_IMM));
@@ -1115,7 +1098,7 @@ finalize_exec(Port *pp, ErtsPortTask **execq, int processing_busy_q)
 static ERTS_INLINE erts_aint32_t
 select_queue_for_exec(Port *pp, ErtsPortTask **execqp, int *processing_busy_q_p)
 {
-    erts_aint32_t flags = erts_smp_atomic32_read_nob(&pp->sched.flags);
+    erts_aint32_t flags = erts_atomic32_read_nob(&pp->sched.flags);
 
     if (flags & ERTS_PTS_FLG_CHK_UNSET_BUSY_PORT_Q)
 	flags = check_unset_busy_port_q(pp, flags, pp->sched.taskq.bpq);
@@ -1225,7 +1208,7 @@ fetch_in_queue(Port *pp, ErtsPortTask **execqp)
     if (ptp)
 	*execqp = ptp->u.alive.next;
     else
-	erts_smp_atomic32_read_band_nob(&pp->sched.flags,
+	erts_atomic32_read_band_nob(&pp->sched.flags,
 					~ERTS_PTS_FLG_HAVE_TASKS);
 
     
@@ -1288,7 +1271,7 @@ erl_drv_consume_timeslice(ErlDrvPort dprt, int percent)
 void
 erts_port_task_tmp_handle_detach(ErtsPortTaskHandle *pthp)
 {
-    ERTS_SMP_LC_ASSERT(erts_thr_progress_lc_is_delaying());
+    ERTS_LC_ASSERT(erts_thr_progress_lc_is_delaying());
     reset_port_task_handle(pthp);
 }
 
@@ -1301,9 +1284,7 @@ erts_port_task_abort(ErtsPortTaskHandle *pthp)
 {
     int res;
     ErtsPortTask *ptp;
-#ifdef ERTS_SMP
     ErtsThrPrgrDelayHandle dhndl = erts_thr_progress_unmanaged_delay();
-#endif
 
     ptp = handle2task(pthp);
     if (!ptp)
@@ -1313,41 +1294,25 @@ erts_port_task_abort(ErtsPortTaskHandle *pthp)
 
 #ifdef DEBUG
 	ErtsPortTaskHandle *saved_pthp = ptp->u.alive.handle;
-	ERTS_SMP_READ_MEMORY_BARRIER;
-	old_state = erts_smp_atomic32_read_nob(&ptp->state);
+	ERTS_THR_READ_MEMORY_BARRIER;
+	old_state = erts_atomic32_read_nob(&ptp->state);
 	if (old_state == ERTS_PT_STATE_SCHEDULED) {
 	    ASSERT(!saved_pthp || saved_pthp == pthp);
 	}
 #endif
 
-	old_state = erts_smp_atomic32_cmpxchg_nob(&ptp->state,
+	old_state = erts_atomic32_cmpxchg_nob(&ptp->state,
 						  ERTS_PT_STATE_ABORTED,
 						  ERTS_PT_STATE_SCHEDULED);
 	if (old_state != ERTS_PT_STATE_SCHEDULED)
 	    res = - 1; /* Task already aborted, executing, or executed */
 	else {
-
 	    reset_port_task_handle(pthp);
-
-	    switch (ptp->type) {
-	    case ERTS_PORT_TASK_INPUT:
-	    case ERTS_PORT_TASK_OUTPUT:
-	    case ERTS_PORT_TASK_EVENT:
-		ASSERT(erts_smp_atomic_read_nob(
-			   &erts_port_task_outstanding_io_tasks) > 0);
-		erts_smp_atomic_dec_relb(&erts_port_task_outstanding_io_tasks);
-		break;
-	    default:
-		break;
-	    }
-
 	    res = 0;
 	}
     }
 
-#ifdef ERTS_SMP
     erts_thr_progress_unmanaged_continue(dhndl);
-#endif
 
     return res;
 }
@@ -1356,12 +1321,10 @@ void
 erts_port_task_abort_nosuspend_tasks(Port *pp)
 {
     ErtsPortTaskHandleList *abort_list;
-#ifdef ERTS_SMP
     ErtsThrPrgrDelayHandle dhndl = ERTS_THR_PRGR_DHANDLE_INVALID;
-#endif
 
     erts_port_task_sched_lock(&pp->sched);
-    erts_smp_atomic32_read_band_nob(&pp->sched.flags,
+    erts_atomic32_read_band_nob(&pp->sched.flags,
 				    ~ERTS_PTS_FLG_HAVE_NS_TASKS);
     abort_list = pp->sched.taskq.local.busy.nosuspend;
     pp->sched.taskq.local.busy.nosuspend = NULL;
@@ -1381,40 +1344,34 @@ erts_port_task_abort_nosuspend_tasks(Port *pp)
 	pthlp = abort_list;
 	abort_list = pthlp->u.next;
 
-#ifdef ERTS_SMP
 	if (dhndl != ERTS_THR_PRGR_DHANDLE_MANAGED)
 	    dhndl = erts_thr_progress_unmanaged_delay();
-#endif
 
 	pthp = &pthlp->handle;
 	ptp = handle2task(pthp);
 	if (!ptp) {
-#ifdef ERTS_SMP
 	    if (dhndl != ERTS_THR_PRGR_DHANDLE_MANAGED)
 		erts_thr_progress_unmanaged_continue(dhndl);
-#endif
 	    schedule_port_task_handle_list_free(pthlp);
 	    continue;
 	}
 
 #ifdef DEBUG
 	saved_pthp = ptp->u.alive.handle;
-	ERTS_SMP_READ_MEMORY_BARRIER;
-	old_state = erts_smp_atomic32_read_nob(&ptp->state);
+	ERTS_THR_READ_MEMORY_BARRIER;
+	old_state = erts_atomic32_read_nob(&ptp->state);
 	if (old_state == ERTS_PT_STATE_SCHEDULED) {
 	    ASSERT(saved_pthp == pthp);
 	}
 #endif
 
-	old_state = erts_smp_atomic32_cmpxchg_nob(&ptp->state,
+	old_state = erts_atomic32_cmpxchg_nob(&ptp->state,
 						  ERTS_PT_STATE_ABORTED,
 						  ERTS_PT_STATE_SCHEDULED);
 	if (old_state != ERTS_PT_STATE_SCHEDULED) {
 	    /* Task already aborted, executing, or executed */
-#ifdef ERTS_SMP
 	    if (dhndl != ERTS_THR_PRGR_DHANDLE_MANAGED)
 		erts_thr_progress_unmanaged_continue(dhndl);
-#endif
 	    schedule_port_task_handle_list_free(pthlp);
 	    continue;
 	}
@@ -1424,10 +1381,8 @@ erts_port_task_abort_nosuspend_tasks(Port *pp)
 	type = ptp->type;
 	td = ptp->u.alive.td;
 
-#ifdef ERTS_SMP
 	if (dhndl != ERTS_THR_PRGR_DHANDLE_MANAGED)
 	    erts_thr_progress_unmanaged_continue(dhndl);
-#endif
 	schedule_port_task_handle_list_free(pthlp);
 
 	abort_nosuspend_task(pp, type, &td, pp->sched.taskq.bpq != NULL);
@@ -1446,10 +1401,8 @@ erts_port_task_schedule(Eterm id,
 {
     ErtsProc2PortSigData *sigdp = NULL;
     ErtsPortTaskHandleList *ns_pthlp = NULL;
-#ifdef ERTS_SMP
     ErtsRunQueue *xrunq;
     ErtsThrPrgrDelayHandle dhndl;
-#endif
     ErtsRunQueue *runq;
     Port *pp;
     ErtsPortTask *ptp = NULL;
@@ -1460,19 +1413,15 @@ erts_port_task_schedule(Eterm id,
 
     ASSERT(is_internal_port(id));
 
-#ifdef ERTS_SMP
     dhndl = erts_thr_progress_unmanaged_delay();
-#endif
 
     pp = erts_port_lookup_raw(id);
 
-#ifdef ERTS_SMP
     if (dhndl != ERTS_THR_PRGR_DHANDLE_MANAGED) {
 	if (pp)
 	    erts_port_inc_refc(pp);
 	erts_thr_progress_unmanaged_continue(dhndl);
     }
-#endif
 
     if (type != ERTS_PORT_TASK_PROC_SIG) {
         if (!pp)
@@ -1483,7 +1432,7 @@ erts_port_task_schedule(Eterm id,
 	ptp->type = type;
 	ptp->u.alive.flags = 0;
 
-	erts_smp_atomic32_init_nob(&ptp->state, ERTS_PT_STATE_SCHEDULED);
+	erts_atomic32_init_nob(&ptp->state, ERTS_PT_STATE_SCHEDULED);
 
 	set_handle(ptp, pthp);
     }
@@ -1495,16 +1444,6 @@ erts_port_task_schedule(Eterm id,
 	va_start(argp, type);
 	ptp->u.alive.td.io.event = va_arg(argp, ErlDrvEvent);
 	va_end(argp);
-	erts_smp_atomic_inc_relb(&erts_port_task_outstanding_io_tasks);
-	break;
-    }
-    case ERTS_PORT_TASK_EVENT: {
-	va_list argp;
-	va_start(argp, type);
-	ptp->u.alive.td.io.event = va_arg(argp, ErlDrvEvent);
-	ptp->u.alive.td.io.event_data = va_arg(argp, ErlDrvEventData);
-	va_end(argp);
-	erts_smp_atomic_inc_relb(&erts_port_task_outstanding_io_tasks);
 	break;
     }
     case ERTS_PORT_TASK_PROC_SIG: {
@@ -1559,7 +1498,7 @@ erts_port_task_schedule(Eterm id,
 	if (!(act & (ERTS_PTS_FLG_IN_RUNQ|ERTS_PTS_FLG_EXEC)))
 	    new |= ERTS_PTS_FLG_IN_RUNQ;
 
-	act = erts_smp_atomic32_cmpxchg_relb(&pp->sched.flags, new, exp);
+	act = erts_atomic32_cmpxchg_relb(&pp->sched.flags, new, exp);
 
 	if (exp == act) {
 	    if (!(act & (ERTS_PTS_FLG_IN_RUNQ|ERTS_PTS_FLG_EXEC)))
@@ -1584,44 +1523,38 @@ erts_port_task_schedule(Eterm id,
     if (!runq)
 	ERTS_INTERNAL_ERROR("Missing run-queue");
 
-#ifdef ERTS_SMP
     xrunq = erts_check_emigration_need(runq, ERTS_PORT_PRIO_LEVEL);
-    ERTS_SMP_LC_ASSERT(runq != xrunq);
-    ERTS_SMP_LC_VERIFY_RQ(runq, pp);
+    ERTS_LC_ASSERT(runq != xrunq);
+    ERTS_LC_VERIFY_RQ(runq, pp);
     if (xrunq) {
 	/* Emigrate port ... */
-	erts_smp_atomic_set_nob(&pp->run_queue, (erts_aint_t) xrunq);
-	erts_smp_runq_unlock(runq);
+	erts_atomic_set_nob(&pp->run_queue, (erts_aint_t) xrunq);
+	erts_runq_unlock(runq);
 	runq = erts_port_runq(pp);
 	if (!runq)
 	    ERTS_INTERNAL_ERROR("Missing run-queue");
     }
-#endif
 
     enqueue_port(runq, pp);
 
-    erts_smp_runq_unlock(runq);
+    erts_runq_unlock(runq);
 
-    erts_smp_notify_inc_runq(runq);
+    erts_notify_inc_runq(runq);
 
 done:
 
     if (prof_runnable_ports)
 	erts_port_task_sched_unlock(&pp->sched);
 
-#ifdef ERTS_SMP
     if (dhndl != ERTS_THR_PRGR_DHANDLE_MANAGED)
 	erts_port_dec_refc(pp);
-#endif
 
     return 0;
 
 abort_nosuspend:
 
-#ifdef ERTS_SMP
     if (dhndl != ERTS_THR_PRGR_DHANDLE_MANAGED)
 	erts_port_dec_refc(pp);
-#endif
 
     abort_nosuspend_task(pp, ptp->type, &ptp->u.alive.td, 0);
 
@@ -1635,10 +1568,8 @@ abort_nosuspend:
 
 fail:
 
-#ifdef ERTS_SMP
     if (dhndl != ERTS_THR_PRGR_DHANDLE_MANAGED)
 	erts_port_dec_refc(pp);
-#endif
 
     if (ptp) {
         abort_signal_task(pp, ERTS_PROC2PORT_SIG_ABORT,
@@ -1658,14 +1589,14 @@ erts_port_task_free_port(Port *pp)
     erts_aint32_t flags;
     ErtsRunQueue *runq;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(pp));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(pp));
     ASSERT(!(erts_atomic32_read_nob(&pp->state) & ERTS_PORT_SFLGS_DEAD));
 
     runq = erts_port_runq(pp);
     if (!runq)
 	ERTS_INTERNAL_ERROR("Missing run-queue");
     erts_port_task_sched_lock(&pp->sched);
-    flags = erts_smp_atomic32_read_bor_relb(&pp->sched.flags,
+    flags = erts_atomic32_read_bor_relb(&pp->sched.flags,
 					    ERTS_PTS_FLG_EXIT);
     erts_port_task_sched_unlock(&pp->sched);
     erts_atomic32_read_bset_relb(&pp->state,
@@ -1675,7 +1606,7 @@ erts_port_task_free_port(Port *pp)
 				  | ERTS_PORT_SFLG_FREE),
 				 ERTS_PORT_SFLG_FREE);
 
-    erts_smp_runq_unlock(runq);
+    erts_runq_unlock(runq);
 
     if (!(flags & (ERTS_PTS_FLG_IN_RUNQ|ERTS_PTS_FLG_EXEC)))
 	begin_port_cleanup(pp, NULL, NULL);
@@ -1688,13 +1619,12 @@ erts_port_task_free_port(Port *pp)
  * scheduling of processes. Run-queue lock should be held by caller.
  */
 
-int
+void
 erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
 {
     Port *pp;
     ErtsPortTask *execq;
     int processing_busy_q;
-    int res = 0;
     int vreds = 0;
     int reds = 0;
     erts_aint_t io_tasks_executed = 0;
@@ -1705,17 +1635,16 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
     ErtsSchedulerData *esdp = runq->scheduler;
     ERTS_MSACC_PUSH_STATE_M();
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(runq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(runq));
 
     pp = pop_port(runq);
     if (!pp) {
-	res = 0;
 	goto done;
     }
 
-    ERTS_SMP_LC_VERIFY_RQ(runq, pp);
+    ERTS_LC_VERIFY_RQ(runq, pp);
 
-    erts_smp_runq_unlock(runq);
+    erts_runq_unlock(runq);
 
     *curr_port_pp = pp;
     
@@ -1723,19 +1652,19 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
 	Uint old = ERTS_PORT_SCHED_ID(pp, esdp->no);
 	int migrated = old && old != esdp->no;
 
-	erts_smp_spin_lock(&erts_sched_stat.lock);
+	erts_spin_lock(&erts_sched_stat.lock);
 	erts_sched_stat.prio[ERTS_PORT_PRIO_LEVEL].total_executed++;
 	erts_sched_stat.prio[ERTS_PORT_PRIO_LEVEL].executed++;
 	if (migrated) {
 	    erts_sched_stat.prio[ERTS_PORT_PRIO_LEVEL].total_migrated++;
 	    erts_sched_stat.prio[ERTS_PORT_PRIO_LEVEL].migrated++;
 	}
-	erts_smp_spin_unlock(&erts_sched_stat.lock);
+	erts_spin_unlock(&erts_sched_stat.lock);
     }
 
     prepare_exec(pp, &execq, &processing_busy_q);
 
-    erts_smp_port_lock(pp);
+    erts_port_lock(pp);
 
     /* trace port scheduling, in */
     if (IS_TRACED_FL(pp, F_TRACE_SCHED_PORTS)) {
@@ -1757,7 +1686,7 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
 	if (!ptp)
 	    break;
 
-	task_state = erts_smp_atomic32_cmpxchg_nob(&ptp->state,
+	task_state = erts_atomic32_cmpxchg_nob(&ptp->state,
 						   ERTS_PT_STATE_EXECUTING,
 						   ERTS_PT_STATE_SCHEDULED);
 	if (task_state != ERTS_PT_STATE_SCHEDULED) {
@@ -1769,8 +1698,8 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
 	    start_time = erts_timestamp_millis();
 	}
 
-	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(pp));
-	ERTS_SMP_CHK_NO_PROC_LOCKS;
+	ERTS_LC_ASSERT(erts_lc_is_port_locked(pp));
+	ERTS_CHK_NO_PROC_LOCKS;
 	ASSERT(pp->drv_ptr);
 
 	switch (ptp->type) {
@@ -1812,17 +1741,6 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
 	    reset_executed_io_task_handle(ptp);
 	    io_tasks_executed++;
 	    break;
-	case ERTS_PORT_TASK_EVENT:
-	    reds = ERTS_PORT_REDS_EVENT;
-	    ASSERT((state & ERTS_PORT_SFLGS_DEAD) == 0);
-            DTRACE_DRIVER(driver_event, pp);
-            LTTNG_DRIVER(driver_event, pp);
-	    (*pp->drv_ptr->event)((ErlDrvData) pp->drv_data,
-				  ptp->u.alive.td.io.event,
-				  ptp->u.alive.td.io.event_data);
-	    reset_executed_io_task_handle(ptp);
-	    io_tasks_executed++;
-	    break;
 	case ERTS_PORT_TASK_PROC_SIG: {
 	    ErtsProc2PortSigData *sigdp = &ptp->u.alive.td.psig.data;
 	    reset_handle(ptp);
@@ -1887,17 +1805,7 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
     erts_unblock_fpe(fpe_was_unmasked);
     ERTS_MSACC_POP_STATE_M();
 
-
-    if (io_tasks_executed) {
-	ASSERT(erts_smp_atomic_read_nob(&erts_port_task_outstanding_io_tasks)
-	       >= io_tasks_executed);
-	erts_smp_atomic_add_relb(&erts_port_task_outstanding_io_tasks,
-				 -1*io_tasks_executed);
-    }
-
-#ifdef ERTS_SMP
-    ASSERT(runq == (ErtsRunQueue *) erts_smp_atomic_read_nob(&pp->run_queue));
-#endif
+    ASSERT(runq == (ErtsRunQueue *) erts_atomic_read_nob(&pp->run_queue));
 
     active = finalize_exec(pp, &execq, processing_busy_q);
 
@@ -1907,54 +1815,43 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
 
     *curr_port_pp = NULL;
 
-    erts_smp_runq_lock(runq);
+    erts_runq_lock(runq);
  
     if (active) {
-#ifdef ERTS_SMP
 	ErtsRunQueue *xrunq;
-#endif
 
 	ASSERT(!(erts_atomic32_read_nob(&pp->state) & ERTS_PORT_SFLGS_DEAD));
 
-#ifdef ERTS_SMP
 	xrunq = erts_check_emigration_need(runq, ERTS_PORT_PRIO_LEVEL);
-	ERTS_SMP_LC_ASSERT(runq != xrunq);
-	ERTS_SMP_LC_VERIFY_RQ(runq, pp);
+	ERTS_LC_ASSERT(runq != xrunq);
+	ERTS_LC_VERIFY_RQ(runq, pp);
 	if (!xrunq) {
-#endif
 	    enqueue_port(runq, pp);
 	    /* No need to notify ourselves about inc in runq. */
-#ifdef ERTS_SMP
 	}
 	else {
 	    /* Emigrate port... */
-	    erts_smp_atomic_set_nob(&pp->run_queue, (erts_aint_t) xrunq);
-	    erts_smp_runq_unlock(runq);
+	    erts_atomic_set_nob(&pp->run_queue, (erts_aint_t) xrunq);
+	    erts_runq_unlock(runq);
 
 	    xrunq = erts_port_runq(pp);
 	    ASSERT(xrunq);
 	    enqueue_port(xrunq, pp);
-	    erts_smp_runq_unlock(xrunq);
-	    erts_smp_notify_inc_runq(xrunq);
+	    erts_runq_unlock(xrunq);
+	    erts_notify_inc_runq(xrunq);
 
-	    erts_smp_runq_lock(runq);
+	    erts_runq_lock(runq);
 	}
-#endif
     }
 
  done:
-    res = (erts_smp_atomic_read_nob(&erts_port_task_outstanding_io_tasks)
-	   != (erts_aint_t) 0);
 
     runq->scheduler->reductions += reds;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(runq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(runq));
     ERTS_PORT_REDUCTIONS_EXECUTED(esdp, runq, reds);
-
-    return res;
 }
 
-#ifdef ERTS_SMP
 static void
 release_port(void *vport)
 {
@@ -1970,7 +1867,6 @@ schedule_release_port(void *vport) {
 				  &pp->common.u.release);
 }
 
-#endif
 
 static void
 begin_port_cleanup(Port *pp, ErtsPortTask **execqp, int *processing_busy_q_p)
@@ -1981,7 +1877,7 @@ begin_port_cleanup(Port *pp, ErtsPortTask **execqp, int *processing_busy_q_p)
     ErtsPortTaskHandleList *free_nshp = NULL;
     ErtsProcList *plp;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(pp));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(pp));
 
     /*
      * Abort remaining tasks...
@@ -2054,11 +1950,11 @@ begin_port_cleanup(Port *pp, ErtsPortTask **execqp, int *processing_busy_q_p)
 	    qs[i] = ptp->u.alive.next;
 
 	    /* Normal case here is aborted tasks... */
-	    state = erts_smp_atomic32_read_nob(&ptp->state);
+	    state = erts_atomic32_read_nob(&ptp->state);
 	    if (state == ERTS_PT_STATE_ABORTED)
 		goto aborted_port_task;
 
-	    state = erts_smp_atomic32_cmpxchg_nob(&ptp->state,
+	    state = erts_atomic32_cmpxchg_nob(&ptp->state,
 						  ERTS_PT_STATE_EXECUTING,
 						  ERTS_PT_STATE_SCHEDULED);
 	    if (state != ERTS_PT_STATE_SCHEDULED) {
@@ -2085,13 +1981,6 @@ begin_port_cleanup(Port *pp, ErtsPortTask **execqp, int *processing_busy_q_p)
 				      DO_WRITE,
 				      1);
 		break;
-	    case ERTS_PORT_TASK_EVENT:
-		erts_stale_drv_select(pp->common.id,
-				      ERTS_Port2ErlDrvPort(pp),
-				      ptp->u.alive.td.io.event,
-				      0,
-				      1);
-		break;
 	    case ERTS_PORT_TASK_DIST_CMD:
 		break;
 	    case ERTS_PORT_TASK_PROC_SIG: {
@@ -2122,7 +2011,7 @@ begin_port_cleanup(Port *pp, ErtsPortTask **execqp, int *processing_busy_q_p)
 	}
     }
 
-    erts_smp_atomic32_read_band_nob(&pp->sched.flags,
+    erts_atomic32_read_band_nob(&pp->sched.flags,
 				    ~(ERTS_PTS_FLG_HAVE_BUSY_TASKS
 				      |ERTS_PTS_FLG_HAVE_TASKS
 				      |ERTS_PTS_FLGS_BUSY));
@@ -2164,7 +2053,6 @@ begin_port_cleanup(Port *pp, ErtsPortTask **execqp, int *processing_busy_q_p)
     /*
      * Schedule cleanup of port structure...
      */
-#ifdef ERTS_SMP
     /* We might not be a scheduler, eg. traceing to port we are sys_msg_dispatcher */
     if (!erts_get_scheduler_data()) {
       erts_schedule_misc_aux_work(1, schedule_release_port, (void*)pp);
@@ -2174,19 +2062,15 @@ begin_port_cleanup(Port *pp, ErtsPortTask **execqp, int *processing_busy_q_p)
 				      (void *) pp,
 				      &pp->common.u.release);
     }
-#else
-    pp->cleanup = 1;
-#endif
 }
 
-#ifdef ERTS_SMP
 
 void
 erts_enqueue_port(ErtsRunQueue *rq, Port *pp)
 {
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
-    ASSERT(rq == (ErtsRunQueue *) erts_smp_atomic_read_nob(&pp->run_queue));
-    ASSERT(erts_smp_atomic32_read_nob(&pp->sched.flags) & ERTS_PTS_FLG_IN_RUNQ);
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
+    ASSERT(rq == (ErtsRunQueue *) erts_atomic_read_nob(&pp->run_queue));
+    ASSERT(erts_atomic32_read_nob(&pp->sched.flags) & ERTS_PTS_FLG_IN_RUNQ);
     enqueue_port(rq, pp);
 }
 
@@ -2194,16 +2078,15 @@ Port *
 erts_dequeue_port(ErtsRunQueue *rq)
 {
     Port *pp;
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
     pp = pop_port(rq);
     ASSERT(!pp
-	   || rq == (ErtsRunQueue *) erts_smp_atomic_read_nob(&pp->run_queue));
-    ASSERT(!pp || (erts_smp_atomic32_read_nob(&pp->sched.flags)
+	   || rq == (ErtsRunQueue *) erts_atomic_read_nob(&pp->run_queue));
+    ASSERT(!pp || (erts_atomic32_read_nob(&pp->sched.flags)
 		   & ERTS_PTS_FLG_IN_RUNQ));
     return pp;
 }
 
-#endif
 
 /*
  * Initialize the module.
@@ -2211,8 +2094,7 @@ erts_dequeue_port(ErtsRunQueue *rq)
 void
 erts_port_task_init(void)
 {
-    erts_smp_atomic_init_nob(&erts_port_task_outstanding_io_tasks,
-			     (erts_aint_t) 0);
-    init_port_task_alloc();
+    init_port_task_alloc(erts_no_schedulers + erts_no_poll_threads
+                         + 1); /* aux_thread */
     init_busy_caller_table_alloc();
 }
diff --git a/erts/emulator/beam/erl_port_task.h b/erts/emulator/beam/erl_port_task.h
index 39f403b443..ae78a7d8a3 100644
--- a/erts/emulator/beam/erl_port_task.h
+++ b/erts/emulator/beam/erl_port_task.h
@@ -27,11 +27,11 @@
 #ifndef ERTS_PORT_TASK_H_BASIC_TYPES__
 #define ERTS_PORT_TASK_H_BASIC_TYPES__
 #include "erl_sys_driver.h"
-#include "erl_smp.h"
+#include "erl_threads.h"
 #define ERL_PORT_GET_PORT_TYPE_ONLY__
 #include "erl_port.h"
 #undef ERL_PORT_GET_PORT_TYPE_ONLY__
-typedef erts_smp_atomic_t ErtsPortTaskHandle;
+typedef erts_atomic_t ErtsPortTaskHandle;
 #endif
 
 #ifndef ERTS_PORT_TASK_ONLY_BASIC_TYPES__
@@ -56,17 +56,11 @@ typedef erts_smp_atomic_t ErtsPortTaskHandle;
 typedef enum {
     ERTS_PORT_TASK_INPUT,
     ERTS_PORT_TASK_OUTPUT,
-    ERTS_PORT_TASK_EVENT,
     ERTS_PORT_TASK_TIMEOUT,
     ERTS_PORT_TASK_DIST_CMD,
     ERTS_PORT_TASK_PROC_SIG
 } ErtsPortTaskType;
 
-#ifdef ERTS_INCLUDE_SCHEDULER_INTERNALS
-/* NOTE: Do not access any of the exported variables directly */
-extern erts_smp_atomic_t erts_port_task_outstanding_io_tasks;
-#endif
-
 #define ERTS_PTS_FLG_IN_RUNQ			(((erts_aint32_t) 1) <<  0)
 #define ERTS_PTS_FLG_EXEC			(((erts_aint32_t) 1) <<  1)
 #define ERTS_PTS_FLG_HAVE_TASKS			(((erts_aint32_t) 1) <<  2)
@@ -98,8 +92,8 @@ extern erts_smp_atomic_t erts_port_task_outstanding_io_tasks;
 
 typedef struct {
     ErlDrvSizeT high;
-    erts_smp_atomic_t low;
-    erts_smp_atomic_t size;
+    erts_atomic_t low;
+    erts_atomic_t size;
 }  ErtsPortTaskBusyPortQ;
 
 typedef struct ErtsPortTask_ ErtsPortTask;
@@ -124,10 +118,8 @@ typedef struct {
 	} in;
 	ErtsPortTaskBusyPortQ *bpq;
     } taskq;
-    erts_smp_atomic32_t flags;
-#ifdef ERTS_SMP
+    erts_atomic32_t flags;
     erts_mtx_t mtx;
-#endif
 } ErtsPortTaskSched;
 
 ERTS_GLB_INLINE void erts_port_task_handle_init(ErtsPortTaskHandle *pthp);
@@ -142,22 +134,18 @@ ERTS_GLB_INLINE void erts_port_task_sched_unlock(ErtsPortTaskSched *ptsp);
 ERTS_GLB_INLINE int erts_port_task_sched_lock_is_locked(ErtsPortTaskSched *ptsp);
 ERTS_GLB_INLINE void erts_port_task_sched_enter_exiting_state(ErtsPortTaskSched *ptsp);
 
-#ifdef ERTS_INCLUDE_SCHEDULER_INTERNALS
-ERTS_GLB_INLINE int erts_port_task_have_outstanding_io_tasks(void);
-#endif
-
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
 ERTS_GLB_INLINE void
 erts_port_task_handle_init(ErtsPortTaskHandle *pthp)
 {
-    erts_smp_atomic_init_nob(pthp, (erts_aint_t) NULL);
+    erts_atomic_init_nob(pthp, (erts_aint_t) NULL);
 }
 
 ERTS_GLB_INLINE int
 erts_port_task_is_scheduled(ErtsPortTaskHandle *pthp)
 {
-    return ((void *) erts_smp_atomic_read_acqb(pthp)) != NULL;
+    return ((void *) erts_atomic_read_acqb(pthp)) != NULL;
 }
 
 ERTS_GLB_INLINE void erts_port_task_pre_init_sched(ErtsPortTaskSched *ptsp,
@@ -165,9 +153,9 @@ ERTS_GLB_INLINE void erts_port_task_pre_init_sched(ErtsPortTaskSched *ptsp,
 {
     if (bpq) {
 	erts_aint_t low = (erts_aint_t) ERTS_PORT_TASK_DEFAULT_BUSY_PORT_Q_LOW;
-	erts_smp_atomic_init_nob(&bpq->low, low);
+	erts_atomic_init_nob(&bpq->low, low);
  	bpq->high = (ErlDrvSizeT) ERTS_PORT_TASK_DEFAULT_BUSY_PORT_Q_HIGH;
-	erts_smp_atomic_init_nob(&bpq->size, (erts_aint_t) 0);
+	erts_atomic_init_nob(&bpq->size, (erts_aint_t) 0);
     }
     ptsp->taskq.bpq = bpq;
 }
@@ -175,9 +163,7 @@ ERTS_GLB_INLINE void erts_port_task_pre_init_sched(ErtsPortTaskSched *ptsp,
 ERTS_GLB_INLINE void
 erts_port_task_init_sched(ErtsPortTaskSched *ptsp, Eterm instr_id)
 {
-#ifdef ERTS_SMP
     char *lock_str = "port_sched_lock";
-#endif
     ptsp->next = NULL;
     ptsp->taskq.local.busy.first = NULL;
     ptsp->taskq.local.busy.last = NULL;
@@ -186,32 +172,26 @@ erts_port_task_init_sched(ErtsPortTaskSched *ptsp, Eterm instr_id)
     ptsp->taskq.local.first = NULL;
     ptsp->taskq.in.first = NULL;
     ptsp->taskq.in.last = NULL;
-    erts_smp_atomic32_init_nob(&ptsp->flags, 0);
-#ifdef ERTS_SMP
+    erts_atomic32_init_nob(&ptsp->flags, 0);
     erts_mtx_init(&ptsp->mtx, lock_str, instr_id, ERTS_LOCK_FLAGS_CATEGORY_IO);
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_port_task_sched_lock(ErtsPortTaskSched *ptsp)
 {
-#ifdef ERTS_SMP
     erts_mtx_lock(&ptsp->mtx);
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_port_task_sched_unlock(ErtsPortTaskSched *ptsp)
 {
-#ifdef ERTS_SMP
     erts_mtx_unlock(&ptsp->mtx);
-#endif
 }
 
 ERTS_GLB_INLINE int
 erts_port_task_sched_lock_is_locked(ErtsPortTaskSched *ptsp)
 {
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     return erts_lc_mtx_is_locked(&ptsp->mtx);
 #else
     return 0;
@@ -222,35 +202,25 @@ erts_port_task_sched_lock_is_locked(ErtsPortTaskSched *ptsp)
 ERTS_GLB_INLINE void
 erts_port_task_fini_sched(ErtsPortTaskSched *ptsp)
 {
-#ifdef ERTS_SMP
     erts_mtx_destroy(&ptsp->mtx);
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_port_task_sched_enter_exiting_state(ErtsPortTaskSched *ptsp)
 {
-    erts_smp_atomic32_read_bor_nob(&ptsp->flags, ERTS_PTS_FLG_EXITING);
-}
-
-#ifdef ERTS_INCLUDE_SCHEDULER_INTERNALS
-
-ERTS_GLB_INLINE int
-erts_port_task_have_outstanding_io_tasks(void)
-{
-    return (erts_smp_atomic_read_acqb(&erts_port_task_outstanding_io_tasks)
-	    != 0);
+    erts_atomic32_read_bor_nob(&ptsp->flags, ERTS_PTS_FLG_EXITING);
 }
 
-#endif /* ERTS_INCLUDE_SCHEDULER_INTERNALS */
-
 #endif
 
 #ifdef ERTS_INCLUDE_SCHEDULER_INTERNALS
-int erts_port_task_execute(ErtsRunQueue *, Port **);
+void erts_port_task_execute(ErtsRunQueue *, Port **);
 void erts_port_task_init(void);
 #endif
 
+/* generated for 'port_task' quick allocator */
+void erts_port_task_pre_alloc_init_thread(void);
+
 void erts_port_task_tmp_handle_detach(ErtsPortTaskHandle *);
 int erts_port_task_abort(ErtsPortTaskHandle *);
 
@@ -265,10 +235,8 @@ ErtsProc2PortSigData *erts_port_task_alloc_p2p_sig_data(void);
 ErtsProc2PortSigData *erts_port_task_alloc_p2p_sig_data_extra(size_t extra, void **extra_ptr);
 void erts_port_task_free_p2p_sig_data(ErtsProc2PortSigData *sigdp);
 
-#ifdef ERTS_SMP
 void erts_enqueue_port(ErtsRunQueue *rq, Port *pp);
 Port *erts_dequeue_port(ErtsRunQueue *rq);
-#endif
 #undef ERTS_INCLUDE_SCHEDULER_INTERNALS
 #endif /* ERL_PORT_TASK_H__ */
 #endif /* ERTS_PORT_TASK_ONLY_BASIC_TYPES__ */
diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c
index 63e9275ac1..a807d60ec7 100644
--- a/erts/emulator/beam/erl_process.c
+++ b/erts/emulator/beam/erl_process.c
@@ -24,6 +24,8 @@
 #  include "config.h"
 #endif
 
+#define ERTS_WANT_BREAK_HANDLING
+
 #include <stddef.h> /* offsetof() */
 #include "sys.h"
 #include "erl_vm.h"
@@ -49,6 +51,8 @@
 #define ERTS_WANT_TIMER_WHEEL_API
 #include "erl_time.h"
 #include "erl_nfunc_sched.h"
+#include "erl_check_io.h"
+#include "erl_poll.h"
 
 #define ERTS_CHECK_TIME_REDS CONTEXT_REDS
 #define ERTS_DELAYED_WAKEUP_INFINITY (~(Uint64) 0)
@@ -127,18 +131,16 @@ runq_got_work_to_execute_flags(Uint32 flags)
     return !ERTS_IS_RUNQ_EMPTY_FLGS(flags);
 }
 
-#ifdef ERTS_SMP
 static ERTS_INLINE int
 runq_got_work_to_execute(ErtsRunQueue *rq)
 {
     return runq_got_work_to_execute_flags(ERTS_RUNQ_FLGS_GET_NOB(rq));
 }
-#endif
 
 #undef RUNQ_READ_RQ
 #undef RUNQ_SET_RQ
-#define RUNQ_READ_RQ(X) ((ErtsRunQueue *) erts_smp_atomic_read_nob((X)))
-#define RUNQ_SET_RQ(X, RQ) erts_smp_atomic_set_nob((X), (erts_aint_t) (RQ))
+#define RUNQ_READ_RQ(X) ((ErtsRunQueue *) erts_atomic_read_nob((X)))
+#define RUNQ_SET_RQ(X, RQ) erts_atomic_set_nob((X), (erts_aint_t) (RQ))
 
 #ifdef DEBUG
 #  if defined(ARCH_64)
@@ -172,7 +174,6 @@ extern BeamInstr beam_exit[];
 extern BeamInstr beam_continue_exit[];
 
 int ERTS_WRITE_UNLIKELY(erts_default_spo_flags) = SPO_ON_HEAP_MSGQ;
-int ERTS_WRITE_UNLIKELY(erts_eager_check_io) = 1;
 int ERTS_WRITE_UNLIKELY(erts_sched_compact_load);
 int ERTS_WRITE_UNLIKELY(erts_sched_balance_util) = 0;
 Uint ERTS_WRITE_UNLIKELY(erts_no_schedulers);
@@ -194,57 +195,51 @@ static UWord thr_prgr_later_cleanup_op_threshold = ERTS_THR_PRGR_LATER_CLEANUP_O
 ErtsPTab erts_proc erts_align_attribute(ERTS_CACHE_LINE_SIZE);
 
 int erts_sched_thread_suggested_stack_size = -1;
-#ifdef ERTS_DIRTY_SCHEDULERS
 int erts_dcpu_sched_thread_suggested_stack_size = -1;
 int erts_dio_sched_thread_suggested_stack_size = -1;
-#endif
 #ifdef ERTS_ENABLE_LOCK_CHECK
 ErtsLcPSDLocks erts_psd_required_locks[ERTS_PSD_SIZE];
 #endif
 
-static struct {
+static struct ErtsSchedBusyWait_ {
     int aux_work;
     int tse;
     int sys_schedule;
 } sched_busy_wait;
 
-#ifdef ERTS_SMP
 int erts_disable_proc_not_running_opt;
 
 static ErtsAuxWorkData *aux_thread_aux_work_data;
+static ErtsAuxWorkData *poll_thread_aux_work_data;
 
 #define ERTS_SCHDLR_SSPND_CHNG_NMSB		(((erts_aint32_t) 1) << 0)
 #define ERTS_SCHDLR_SSPND_CHNG_MSB		(((erts_aint32_t) 1) << 1)
 #define ERTS_SCHDLR_SSPND_CHNG_ONLN		(((erts_aint32_t) 1) << 2)
 #define ERTS_SCHDLR_SSPND_CHNG_DCPU_ONLN	(((erts_aint32_t) 1) << 3)
 
-typedef struct {
+typedef struct ErtsMultiSchedulingBlock_ {
     int ongoing;
     ErtsProcList *blckrs;
     ErtsProcList *chngq;
 } ErtsMultiSchedulingBlock;
 
-typedef struct {
+typedef struct ErtsSchedTypeCounters_ {
     Uint32 normal;
-#ifdef ERTS_DIRTY_SCHEDULERS
     Uint32 dirty_cpu;
     Uint32 dirty_io;
-#endif
 } ErtsSchedTypeCounters;
 
-static struct {
-    erts_smp_mtx_t mtx;
+static struct ErtsSchedSuspend_ {
+    erts_mtx_t mtx;
     ErtsSchedTypeCounters online;
     ErtsSchedTypeCounters curr_online;
     ErtsSchedTypeCounters active;
-    erts_smp_atomic32_t changing;
+    erts_atomic32_t changing;
     ErtsProcList *chngq;
     Eterm changer;
     ErtsMultiSchedulingBlock nmsb; /* Normal multi Scheduling Block */
     ErtsMultiSchedulingBlock msb; /* Multi Scheduling Block */
-#ifdef ERTS_DIRTY_SCHEDULERS
     ErtsSchedType last_msb_dirty_type;
-#endif
 } schdlr_sspnd;
 
 static void init_scheduler_suspend(void);
@@ -253,10 +248,8 @@ static ERTS_INLINE Uint32
 schdlr_sspnd_eq_nscheds(ErtsSchedTypeCounters *val1p, ErtsSchedTypeCounters *val2p)
 {
     int res = val1p->normal == val2p->normal;
-#ifdef ERTS_DIRTY_SCHEDULERS
     res &= val1p->dirty_cpu == val2p->dirty_cpu;
     res &= val1p->dirty_io == val2p->dirty_io;
-#endif
     return res;
 }
 
@@ -267,16 +260,10 @@ schdlr_sspnd_get_nscheds(ErtsSchedTypeCounters *valp,
     switch (type) {
     case ERTS_SCHED_NORMAL:
         return valp->normal;
-#ifdef ERTS_DIRTY_SCHEDULERS
     case ERTS_SCHED_DIRTY_CPU:
         return valp->dirty_cpu;
     case ERTS_SCHED_DIRTY_IO:
         return valp->dirty_io;
-#else
-    case ERTS_SCHED_DIRTY_CPU:
-    case ERTS_SCHED_DIRTY_IO:
-        return 0;
-#endif
     default:
 	ERTS_INTERNAL_ERROR("Invalid scheduler type");
 	return 0;
@@ -288,10 +275,8 @@ static ERTS_INLINE Uint32
 schdlr_sspnd_get_nscheds_tot(ErtsSchedTypeCounters *valp)
 {
     Uint32 res = valp->normal;
-#ifdef ERTS_DIRTY_SCHEDULERS
     res += valp->dirty_cpu;
     res += valp->dirty_io;
-#endif
     return res;
 }
 #endif
@@ -306,14 +291,12 @@ schdlr_sspnd_dec_nscheds(ErtsSchedTypeCounters *valp,
     case ERTS_SCHED_NORMAL:
         valp->normal--;
 	break;
-#ifdef ERTS_DIRTY_SCHEDULERS
     case ERTS_SCHED_DIRTY_CPU:
         valp->dirty_cpu--;
 	break;
     case ERTS_SCHED_DIRTY_IO:
         valp->dirty_io--;
 	break;
-#endif
     default:
 	ERTS_INTERNAL_ERROR("Invalid scheduler type");
     }
@@ -327,14 +310,12 @@ schdlr_sspnd_inc_nscheds(ErtsSchedTypeCounters *valp,
     case ERTS_SCHED_NORMAL:
         valp->normal++;
 	break;
-#ifdef ERTS_DIRTY_SCHEDULERS
     case ERTS_SCHED_DIRTY_CPU:
         valp->dirty_cpu++;
 	break;
     case ERTS_SCHED_DIRTY_IO:
         valp->dirty_io++;
 	break;
-#endif
     default:
 	ERTS_INTERNAL_ERROR("Invalid scheduler type");
     }
@@ -348,25 +329,23 @@ schdlr_sspnd_set_nscheds(ErtsSchedTypeCounters *valp,
     case ERTS_SCHED_NORMAL:
         valp->normal = no;
 	break;
-#ifdef ERTS_DIRTY_SCHEDULERS
     case ERTS_SCHED_DIRTY_CPU:
         valp->dirty_cpu = no;
 	break;
     case ERTS_SCHED_DIRTY_IO:
         valp->dirty_io = no;
 	break;
-#endif
     default:
 	ERTS_INTERNAL_ERROR("Invalid scheduler type");
     }
 }
 
 static struct {
-    erts_smp_mtx_t update_mtx;
-    erts_smp_atomic32_t no_runqs;
+    erts_mtx_t update_mtx;
+    erts_atomic32_t no_runqs;
     int last_active_runqs;
     int forced_check_balance;
-    erts_smp_atomic32_t checking_balance;
+    erts_atomic32_t checking_balance;
     int halftime;
     int full_reds_history_index;
     struct {
@@ -384,51 +363,38 @@ do {							\
     balance_info.prev_rise.reds = (REDS);		\
 } while (0)
 
-#endif
 
 erts_sched_stat_t erts_sched_stat;
 
-#ifdef USE_THREADS
 static erts_tsd_key_t ERTS_WRITE_UNLIKELY(sched_data_key);
-#endif
 
-static erts_smp_atomic32_t function_calls;
-
-#ifdef ERTS_SMP
-static erts_smp_atomic32_t doing_sys_schedule;
-static erts_smp_atomic32_t no_empty_run_queues;
+static erts_atomic32_t no_empty_run_queues;
 long erts_runq_supervision_interval = 0;
 static ethr_event runq_supervision_event;
 static erts_tid_t runq_supervisor_tid;
 static erts_atomic_t runq_supervisor_sleeping;
-#else /* !ERTS_SMP */
-ErtsSchedulerData *erts_scheduler_data;
-#endif
 
 ErtsAlignedRunQueue * ERTS_WRITE_UNLIKELY(erts_aligned_run_queues);
 Uint ERTS_WRITE_UNLIKELY(erts_no_run_queues);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 struct {
     union {
-        erts_smp_atomic32_t active;
+        erts_atomic32_t active;
         char align__[ERTS_CACHE_LINE_SIZE];
     } cpu;
     union {
-        erts_smp_atomic32_t active;
+        erts_atomic32_t active;
         char align__[ERTS_CACHE_LINE_SIZE];
     } io;
 } dirty_count erts_align_attribute(ERTS_CACHE_LINE_SIZE);
 
-#endif
 
 static ERTS_INLINE void
 dirty_active(ErtsSchedulerData *esdp, erts_aint32_t add)
 {
-#ifdef ERTS_DIRTY_SCHEDULERS
     erts_aint32_t val;
-    erts_smp_atomic32_t *ap;
+    erts_atomic32_t *ap;
     switch (esdp->type) {
     case ERTS_SCHED_DIRTY_CPU:
         ap = &dirty_count.cpu.active;
@@ -446,23 +412,20 @@ dirty_active(ErtsSchedulerData *esdp, erts_aint32_t add)
      * All updates done under run-queue lock, so
      * no inc or dec needed...
      */
-    ERTS_SMP_ASSERT(erts_smp_lc_runq_is_locked(esdp->run_queue));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(esdp->run_queue));
 
-    val = erts_smp_atomic32_read_nob(ap);
+    val = erts_atomic32_read_nob(ap);
     val += add;
-    erts_smp_atomic32_set_nob(ap, val);
-#endif
+    erts_atomic32_set_nob(ap, val);
 }
 
 ErtsAlignedSchedulerData * ERTS_WRITE_UNLIKELY(erts_aligned_scheduler_data);
-#ifdef ERTS_DIRTY_SCHEDULERS
 ErtsAlignedSchedulerData * ERTS_WRITE_UNLIKELY(erts_aligned_dirty_cpu_scheduler_data);
 ErtsAlignedSchedulerData * ERTS_WRITE_UNLIKELY(erts_aligned_dirty_io_scheduler_data);
 typedef union {
     Process dsp;
     char align[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(Process))];
 } ErtsAlignedDirtyShadowProcess;
-#endif
 
 typedef union {
     ErtsSchedulerSleepInfo ssi;
@@ -470,12 +433,9 @@ typedef union {
 } ErtsAlignedSchedulerSleepInfo;
 
 static ErtsAlignedSchedulerSleepInfo *aligned_sched_sleep_info;
-#ifdef ERTS_DIRTY_SCHEDULERS
-#ifdef ERTS_SMP
 static ErtsAlignedSchedulerSleepInfo *aligned_dirty_cpu_sched_sleep_info;
 static ErtsAlignedSchedulerSleepInfo *aligned_dirty_io_sched_sleep_info;
-#endif
-#endif
+static ErtsAlignedSchedulerSleepInfo *aligned_poll_thread_sleep_info;
 
 static Uint last_reductions;
 static Uint last_exact_reductions;
@@ -543,11 +503,14 @@ ERTS_SCHED_PREF_QUICK_ALLOC_IMPL(proclist,
 				 200,
 				 ERTS_ALC_T_PROC_LIST)
 
+#define ERTS_POLL_THREAD_SLEEP_INFO_IX(IX)                              \
+        (ASSERT(0 <= ((int) (IX))                                       \
+                && ((int) (IX)) < ((int) erts_no_poll_threads)),        \
+         &aligned_poll_thread_sleep_info[(IX)].ssi)
 #define ERTS_SCHED_SLEEP_INFO_IX(IX)					\
-    (ASSERT(-1 <= ((int) (IX))					        \
-		 && ((int) (IX)) < ((int) erts_no_schedulers)),		\
+    (ASSERT(((int)-1) <= ((int) (IX))                 \
+            && ((int) (IX)) < ((int) erts_no_schedulers)),		\
      &aligned_sched_sleep_info[(IX)].ssi)
-#ifdef ERTS_DIRTY_SCHEDULERS
 #define ERTS_DIRTY_CPU_SCHED_SLEEP_INFO_IX(IX)				\
     (ASSERT(0 <= ((int) (IX))					        \
 	    && ((int) (IX)) < ((int) erts_no_dirty_cpu_schedulers)),	\
@@ -556,7 +519,6 @@ ERTS_SCHED_PREF_QUICK_ALLOC_IMPL(proclist,
     (ASSERT(0 <= ((int) (IX))					        \
 	    && ((int) (IX)) < ((int) erts_no_dirty_io_schedulers)),	\
      &aligned_dirty_io_sched_sleep_info[(IX)].ssi)
-#endif
 
 #define ERTS_FOREACH_RUNQ(RQVAR, DO)					\
 do {									\
@@ -564,9 +526,9 @@ do {									\
     int ix__;								\
     for (ix__ = 0; ix__ < erts_no_run_queues; ix__++) {			\
 	RQVAR = ERTS_RUNQ_IX(ix__);					\
-	erts_smp_runq_lock(RQVAR);					\
+	erts_runq_lock(RQVAR);					\
 	{ DO; }								\
-	erts_smp_runq_unlock(RQVAR);					\
+	erts_runq_unlock(RQVAR);					\
     }									\
 } while (0)
 
@@ -576,12 +538,12 @@ do {									\
     int ix__;								\
     int online__ = (int) schdlr_sspnd_get_nscheds(&schdlr_sspnd.online,	\
 						  ERTS_SCHED_NORMAL);	\
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_mtx_is_locked(&schdlr_sspnd.mtx));	\
+    ERTS_LC_ASSERT(erts_lc_mtx_is_locked(&schdlr_sspnd.mtx));	\
     for (ix__ = 0; ix__ < online__; ix__++) {				\
 	RQVAR = ERTS_RUNQ_IX(ix__);					\
-	erts_smp_runq_lock(RQVAR);					\
+	erts_runq_lock(RQVAR);					\
 	{ DO; }								\
-	erts_smp_runq_unlock(RQVAR);					\
+	erts_runq_unlock(RQVAR);					\
     }									\
 } while (0)
 
@@ -592,12 +554,12 @@ do {									\
     int ix__;								\
     for (ix__ = 0; ix__ < nrqs; ix__++) {                               \
 	RQVAR = ERTS_RUNQ_IX(ix__);					\
-	erts_smp_runq_lock(RQVAR);					\
+	erts_runq_lock(RQVAR);					\
 	{ DO; }								\
     }									\
     { DOX; }								\
     for (ix__ = 0; ix__ < nrqs; ix__++)                                 \
-	erts_smp_runq_unlock(ERTS_RUNQ_IX(ix__));			\
+	erts_runq_unlock(ERTS_RUNQ_IX(ix__));			\
 } while (0)
 
 #define ERTS_ATOMIC_FOREACH_RUNQ(RQVAR, DO)                             \
@@ -638,11 +600,8 @@ dbg_chk_aux_work_val(erts_aint32_t value)
     valid |= ERTS_SSI_AUX_WORK_MISC;
     valid |= ERTS_SSI_AUX_WORK_FIX_ALLOC_LOWER_LIM;
     valid |= ERTS_SSI_AUX_WORK_FIX_ALLOC_DEALLOC;
-#if ERTS_USE_ASYNC_READY_Q
     valid |= ERTS_SSI_AUX_WORK_ASYNC_READY;
     valid |= ERTS_SSI_AUX_WORK_ASYNC_READY_CLEAN;
-#endif
-#ifdef ERTS_SMP
     valid |= ERTS_SSI_AUX_WORK_DELAYED_AW_WAKEUP;
     valid |= ERTS_SSI_AUX_WORK_MISC_THR_PRGR;
     valid |= ERTS_SSI_AUX_WORK_DD;
@@ -651,7 +610,6 @@ dbg_chk_aux_work_val(erts_aint32_t value)
     valid |= ERTS_SSI_AUX_WORK_CNCLD_TMRS_THR_PRGR;
     valid |= ERTS_SSI_AUX_WORK_THR_PRGR_LATER_OP;
     valid |= ERTS_SSI_AUX_WORK_PENDING_EXITERS;
-#endif
 #if HAVE_ERTS_MSEG
     valid |= ERTS_SSI_AUX_WORK_MSEG_CACHE_CHECK;
 #endif
@@ -673,16 +631,14 @@ dbg_chk_aux_work_val(erts_aint32_t value)
 #define ERTS_DBG_CHK_SSI_AUX_WORK(SSI)
 #endif
 
-#ifdef ERTS_SMP
 static void do_handle_pending_exiters(ErtsProcList *);
 static void wake_scheduler(ErtsRunQueue *rq);
-#endif
 
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
 int
-erts_smp_lc_runq_is_locked(ErtsRunQueue *runq)
+erts_lc_runq_is_locked(ErtsRunQueue *runq)
 {
-    return erts_smp_lc_mtx_is_locked(&runq->mtx);
+    return erts_lc_mtx_is_locked(&runq->mtx);
 }
 #endif
 
@@ -690,13 +646,13 @@ erts_smp_lc_runq_is_locked(ErtsRunQueue *runq)
 static ERTS_INLINE Uint64
 ensure_later_proc_interval(Uint64 interval)
 {
-    return erts_smp_ensure_later_interval_nob(erts_ptab_interval(&erts_proc), interval);
+    return erts_ensure_later_interval_nob(erts_ptab_interval(&erts_proc), interval);
 }
 
 Uint64
 erts_get_proc_interval(void)
 {
-    return erts_smp_current_interval_nob(erts_ptab_interval(&erts_proc));
+    return erts_current_interval_nob(erts_ptab_interval(&erts_proc));
 }
 
 Uint64
@@ -708,15 +664,13 @@ erts_ensure_later_proc_interval(Uint64 interval)
 Uint64
 erts_step_proc_interval(void)
 {
-    return erts_smp_step_interval_nob(erts_ptab_interval(&erts_proc));
+    return erts_step_interval_nob(erts_ptab_interval(&erts_proc));
 }
 
 void
 erts_pre_init_process(void)
 {
-#ifdef USE_THREADS
     erts_tsd_key_create(&sched_data_key, "erts_sched_data_key");
-#endif
 
     erts_aux_work_flag_descr[ERTS_SSI_AUX_WORK_DELAYED_AW_WAKEUP_IX]
 	= "DELAYED_AW_WAKEUP";
@@ -796,6 +750,11 @@ erts_pre_init_process(void)
         = ERTS_PSD_ETS_FIXED_TABLES_GET_LOCKS;
     erts_psd_required_locks[ERTS_PSD_ETS_FIXED_TABLES].set_locks
         = ERTS_PSD_ETS_FIXED_TABLES_SET_LOCKS;
+
+    erts_psd_required_locks[ERTS_PSD_DIST_ENTRY].get_locks
+        = ERTS_PSD_DIST_ENTRY_GET_LOCKS;
+    erts_psd_required_locks[ERTS_PSD_DIST_ENTRY].set_locks
+        = ERTS_PSD_DIST_ENTRY_SET_LOCKS;
 #endif
 }
 
@@ -810,10 +769,8 @@ void
 erts_init_process(int ncpu, int proc_tab_size, int legacy_proc_tab)
 {
 
-#ifdef ERTS_SMP
     erts_disable_proc_not_running_opt = 0;
     erts_init_proc_lock(ncpu);
-#endif
 
     init_proclist_alloc();
 
@@ -825,11 +782,7 @@ erts_init_process(int ncpu, int proc_tab_size, int legacy_proc_tab)
 			 sizeof(Process),
 			 "process_table",
 			 legacy_proc_tab,
-#ifdef ERTS_SMP
 			 1
-#else
-			 0
-#endif
 	);
 
     last_reductions = 0;
@@ -841,7 +794,7 @@ erts_late_init_process(void)
 {
     int ix;
 
-    erts_smp_spinlock_init(&erts_sched_stat.lock, "sched_stat", NIL,
+    erts_spinlock_init(&erts_sched_stat.lock, "sched_stat", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_SCHEDULER);
 
     for (ix = 0; ix < ERTS_NO_PRIO_LEVELS; ix++) {
@@ -883,7 +836,6 @@ erts_late_init_process(void)
 static void
 init_sched_wall_time(ErtsSchedulerData *esdp, Uint64 time_stamp)
 {
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (esdp->type != ERTS_SCHED_NORMAL) {
         erts_atomic32_init_nob(&esdp->sched_wall_time.u.mod, 0);
         esdp->sched_wall_time.enabled = 1;
@@ -892,7 +844,6 @@ init_sched_wall_time(ErtsSchedulerData *esdp, Uint64 time_stamp)
         esdp->sched_wall_time.working.start = ERTS_SCHED_WTIME_IDLE;
     }
     else
-#endif
     {
         esdp->sched_wall_time.u.need = erts_sched_balance_util;
         esdp->sched_wall_time.enabled = 0;
@@ -1041,14 +992,14 @@ erts_get_sched_util(ErtsRunQueue *rq, int initially_locked, int short_interval)
 	if (!locked) {
 	    if (++try >= ERTS_GET_AVG_MAX_UNLOCKED_TRY) {
 		/* Writer will eventually block on runq-lock */
-		erts_smp_runq_lock(rq);
+		erts_runq_lock(rq);
 		locked = 1;
 	    }
 	}
     }
 
     if (!initially_locked && locked)
-	erts_smp_runq_unlock(rq);
+	erts_runq_unlock(rq);
 
     now = sched_wall_time_ts();
     worktime = calc_sched_worktime(is_working, now, last, interval, old_worktime);
@@ -1090,7 +1041,6 @@ init_runq_sched_util(ErtsRunQueueSchedUtil *rqsu, int enabled)
 
 #endif /* ERTS_HAVE_SCHED_UTIL_BALANCING_SUPPORT */
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 typedef struct {
     Uint64 working;
@@ -1143,9 +1093,7 @@ read_dirty_sched_wall_time(ErtsSchedulerData *esdp, ErtsDirtySchedWallTime *info
         info->working = info->total;
 }
 
-#endif
 
-#ifdef ERTS_SMP
 
 static void
 dirty_sched_wall_time_change(ErtsSchedulerData *esdp, int working)
@@ -1193,16 +1141,13 @@ dirty_sched_wall_time_change(ErtsSchedulerData *esdp, int working)
     mod++;
     erts_atomic32_set_nob(&esdp->sched_wall_time.u.mod, mod);
 
-#if 0
     if (!working) {
-        ERTS_MSACC_SET_STATE_M_X(ERTS_MSACC_STATE_BUSY_WAIT);
+        ERTS_MSACC_SET_STATE_X(ERTS_MSACC_STATE_BUSY_WAIT);
     } else {
-        ERTS_MSACC_SET_STATE_M_X(ERTS_MSACC_STATE_OTHER);
+        ERTS_MSACC_SET_STATE_X(ERTS_MSACC_STATE_OTHER);
     }
-#endif
 }
 
-#endif /* ERTS_SMP */
 
 static void
 sched_wall_time_change(ErtsSchedulerData *esdp, int working)
@@ -1247,11 +1192,9 @@ typedef struct {
     Eterm ref;
     Eterm ref_heap[ERTS_REF_THING_SIZE];
     Uint req_sched;
-    erts_smp_atomic32_t refc;
-#ifdef ERTS_DIRTY_SCHEDULERS
+    erts_atomic32_t refc;
     int want_dirty_cpu;
     int want_dirty_io;
-#endif
 } ErtsSchedWallTimeReq;
 
 typedef struct {
@@ -1259,7 +1202,7 @@ typedef struct {
     Eterm ref;
     Eterm ref_heap[ERTS_REF_THING_SIZE];
     Uint req_sched;
-    erts_smp_atomic32_t refc;
+    erts_atomic32_t refc;
 } ErtsSystemCheckReq;
 
 
@@ -1291,10 +1234,8 @@ reply_sched_wall_time(void *vswtrp)
     ErlOffHeap *ohp = NULL;
     ErtsMessage *mp = NULL;
 
-    ASSERT(esdp);
-#ifdef ERTS_DIRTY_SCHEDULERS
-    ASSERT(!ERTS_SCHEDULER_IS_DIRTY(esdp));
-#endif
+    ASSERT(esdp && !ERTS_SCHEDULER_IS_DIRTY(esdp));
+
     if (swtrp->set) {
 	if (!swtrp->enable && esdp->sched_wall_time.enabled) {
 	    esdp->sched_wall_time.u.need = erts_sched_balance_util;
@@ -1324,7 +1265,6 @@ reply_sched_wall_time(void *vswtrp)
     hpp = NULL;
     szp = &sz;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (esdp->sched_wall_time.enabled
         && swtrp->req_sched == esdp->no
         && (swtrp->want_dirty_cpu || swtrp->want_dirty_io)) {
@@ -1406,7 +1346,6 @@ reply_sched_wall_time(void *vswtrp)
         erts_free(ERTS_ALC_T_TMP, dswt);
     }
     else
-#endif
     {
         /* Reply with info about this scheduler only... */
 
@@ -1443,11 +1382,11 @@ reply_sched_wall_time(void *vswtrp)
 	rp_locks &= ~ERTS_PROC_LOCK_MAIN;
  
     if (rp_locks)
-	erts_smp_proc_unlock(rp, rp_locks);
+	erts_proc_unlock(rp, rp_locks);
 
     erts_proc_dec_refc(rp);
 
-    if (erts_smp_atomic32_dec_read_nob(&swtrp->refc) == 0)
+    if (erts_atomic32_dec_read_nob(&swtrp->refc) == 0)
 	swtreq_free(vswtrp);
 }
 
@@ -1460,11 +1399,10 @@ erts_sched_wall_time_request(Process *c_p, int set, int enable,
     ErtsSchedWallTimeReq *swtrp;
     Eterm *hp;
 
+    ASSERT(esdp && !ERTS_SCHEDULER_IS_DIRTY(esdp));
+
     if (!set && !esdp->sched_wall_time.enabled)
 	return THE_NON_VALUE;
-#ifdef ERTS_DIRTY_SCHEDULERS
-    ASSERT(!ERTS_SCHEDULER_IS_DIRTY(esdp));
-#endif
 
     swtrp = swtreq_alloc();
     ref = erts_make_ref(c_p);
@@ -1475,22 +1413,18 @@ erts_sched_wall_time_request(Process *c_p, int set, int enable,
     swtrp->proc = c_p;
     swtrp->ref = STORE_NC(&hp, NULL, ref);
     swtrp->req_sched = esdp->no;
-#ifdef ERTS_DIRTY_SCHEDULERS
     swtrp->want_dirty_cpu = want_dirty_cpu;
     swtrp->want_dirty_io = want_dirty_io;
-#endif
-    erts_smp_atomic32_init_nob(&swtrp->refc,
+    erts_atomic32_init_nob(&swtrp->refc,
 			       (erts_aint32_t) erts_no_schedulers);
 
     erts_proc_add_refc(c_p, (Sint32) erts_no_schedulers);
 
-#ifdef ERTS_SMP
     if (erts_no_schedulers > 1)
 	erts_schedule_multi_misc_aux_work(1,
 					  erts_no_schedulers,
 					  reply_sched_wall_time,
 					  (void *) swtrp);
-#endif
 
     reply_sched_wall_time((void *) swtrp);
 
@@ -1511,10 +1445,7 @@ reply_system_check(void *vscrp)
     ErlOffHeap *ohp = NULL;
     ErtsMessage *mp = NULL;
 
-    ASSERT(esdp);
-#ifdef ERTS_DIRTY_SCHEDULERS
-    ASSERT(!ERTS_SCHEDULER_IS_DIRTY(esdp));
-#endif
+    ASSERT(esdp && !ERTS_SCHEDULER_IS_DIRTY(esdp));
 
     sz = ERTS_REF_THING_SIZE;
     mp = erts_alloc_message_heap(rp, &rp_locks, sz, &hp, &ohp);
@@ -1527,11 +1458,11 @@ reply_system_check(void *vscrp)
 	rp_locks &= ~ERTS_PROC_LOCK_MAIN;
 
     if (rp_locks)
-	erts_smp_proc_unlock(rp, rp_locks);
+	erts_proc_unlock(rp, rp_locks);
 
     erts_proc_dec_refc(rp);
 
-    if (erts_smp_atomic32_dec_read_nob(&scrp->refc) == 0)
+    if (erts_atomic32_dec_read_nob(&scrp->refc) == 0)
 	screq_free(vscrp);
 }
 
@@ -1549,17 +1480,15 @@ Eterm erts_system_check_request(Process *c_p) {
     scrp->proc = c_p;
     scrp->ref = STORE_NC(&hp, NULL, ref);
     scrp->req_sched = esdp->no;
-    erts_smp_atomic32_init_nob(&scrp->refc, (erts_aint32_t) erts_no_schedulers);
+    erts_atomic32_init_nob(&scrp->refc, (erts_aint32_t) erts_no_schedulers);
 
     erts_proc_add_refc(c_p, (Sint) erts_no_schedulers);
 
-#ifdef ERTS_SMP
     if (erts_no_schedulers > 1)
 	erts_schedule_multi_misc_aux_work(1,
 					  erts_no_schedulers,
 					  reply_system_check,
 					  (void *) scrp);
-#endif
 
     reply_system_check((void *) scrp);
 
@@ -1620,7 +1549,7 @@ erts_psd_set_init(Process *p, int ix, void *data)
     for (i = 0; i < ERTS_PSD_SIZE; i++)
 	new_psd->data[i] = NULL;
 
-    psd = (ErtsPSD *) erts_smp_atomic_cmpxchg_mb(&p->psd,
+    psd = (ErtsPSD *) erts_atomic_cmpxchg_mb(&p->psd,
 						 (erts_aint_t) new_psd,
 						 (erts_aint_t) NULL);
     if (psd)
@@ -1632,21 +1561,21 @@ erts_psd_set_init(Process *p, int ix, void *data)
     return old;
 }
 
-#ifdef ERTS_SMP
 
 void
-erts_sched_finish_poke(ErtsSchedulerSleepInfo *ssi, erts_aint32_t flags)
+erts_sched_finish_poke(ErtsSchedulerSleepInfo *ssi,
+                       erts_aint32_t flags)
 {
     switch (flags & ERTS_SSI_FLGS_SLEEP_TYPE) {
     case ERTS_SSI_FLG_POLL_SLEEPING:
-	erts_sys_schedule_interrupt(1);
+	erts_check_io_interrupt(ssi->psi, 1);
 	break;
     case ERTS_SSI_FLG_POLL_SLEEPING|ERTS_SSI_FLG_TSE_SLEEPING:
 	/*
 	 * Thread progress blocking while poll sleeping; need
 	 * to signal on both...
 	 */
-	erts_sys_schedule_interrupt(1);
+	erts_check_io_interrupt(ssi->psi, 1);
 	/* fall through */
     case ERTS_SSI_FLG_TSE_SLEEPING:
 	erts_tse_set(ssi->event);
@@ -1660,7 +1589,6 @@ erts_sched_finish_poke(ErtsSchedulerSleepInfo *ssi, erts_aint32_t flags)
     }
 }
 
-#endif
 
 static ERTS_INLINE void
 set_aux_work_flags_wakeup_nob(ErtsSchedulerSleepInfo *ssi,
@@ -1676,11 +1604,7 @@ set_aux_work_flags_wakeup_nob(ErtsSchedulerSleepInfo *ssi,
 	old_flgs = erts_atomic32_read_bor_nob(&ssi->aux_work, flgs);
 
 	if ((old_flgs & flgs) != flgs) {
-#ifdef ERTS_SMP
 	    erts_sched_poke(ssi);
-#else
-	    erts_sys_schedule_interrupt(1);
-#endif
 	}
     }
 }
@@ -1696,11 +1620,7 @@ set_aux_work_flags_wakeup_relb(ErtsSchedulerSleepInfo *ssi,
     old_flgs = erts_atomic32_read_bor_relb(&ssi->aux_work, flgs);
 
     if ((old_flgs & flgs) != flgs) {
-#ifdef ERTS_SMP
 	erts_sched_poke(ssi);
-#else
-	erts_sys_schedule_interrupt(1);
-#endif
     }
 }
 
@@ -1716,7 +1636,6 @@ unset_aux_work_flags(ErtsSchedulerSleepInfo *ssi, erts_aint32_t flgs)
     return erts_atomic32_read_band_nob(&ssi->aux_work, ~flgs);
 }
 
-#ifdef ERTS_SMP
 
 static ERTS_INLINE void
 haw_chk_later_cleanup_op_wakeup(ErtsAuxWorkData *awdp, ErtsThrPrgrVal val)
@@ -1786,9 +1705,9 @@ static ERTS_INLINE void
 haw_thr_prgr_current_check_progress(ErtsAuxWorkData *awdp)
 {
     ErtsThrPrgrVal current = awdp->current_thr_prgr;
-#ifdef ERTS_DIRTY_SCHEDULERS
+
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#endif
+
     if (current != ERTS_THR_PRGR_INVALID
 	&& !erts_thr_progress_equal(current, erts_thr_progress_current())) {
 	/*
@@ -1805,9 +1724,7 @@ handle_delayed_aux_work_wakeup(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, in
 {
     int jix, max_jix;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#endif
 
     ASSERT(awdp->delayed_wakeup.next != ERTS_DELAYED_WAKEUP_INFINITY);
 
@@ -1865,7 +1782,6 @@ schedule_aux_work_wakeup(ErtsAuxWorkData *awdp,
     }
 }
 
-#endif
 
 typedef struct erts_misc_aux_work_t_ erts_misc_aux_work_t;
 struct erts_misc_aux_work_t_ {
@@ -1906,11 +1822,7 @@ init_misc_aux_work(void)
 					   sizeof(erts_algnd_misc_aux_work_q_t)
 					   * (erts_no_schedulers+1));
 
-#ifdef ERTS_SMP
     ix = 0; /* aux_thread + schedulers */
-#else
-    ix = 1; /* scheduler only */
-#endif
 
     for (; ix <= erts_no_schedulers; ix++) {
 	qinit.arg = (void *) ERTS_SCHED_SLEEP_INFO_IX(ix-1);
@@ -1928,10 +1840,8 @@ misc_aux_work_clean(ErtsThrQ_t *q,
 	set_aux_work_flags(awdp->ssi, ERTS_SSI_AUX_WORK_MISC);
 	return aux_work | ERTS_SSI_AUX_WORK_MISC;
     case ERTS_THR_Q_NEED_THR_PRGR:
-#ifdef ERTS_SMP
 	set_aux_work_flags(awdp->ssi, ERTS_SSI_AUX_WORK_MISC_THR_PRGR);
 	haw_thr_prgr_soft_wakeup(awdp, erts_thr_q_need_thr_progress(q));
-#endif
     case ERTS_THR_Q_CLEAN:
 	break;
     }
@@ -1957,16 +1867,14 @@ handle_misc_aux_work(ErtsAuxWorkData *awdp,
     return misc_aux_work_clean(q, awdp, aux_work & ~ERTS_SSI_AUX_WORK_MISC);
 }
 
-#ifdef ERTS_SMP
 
 static ERTS_INLINE erts_aint32_t
 handle_misc_aux_work_thr_prgr(ErtsAuxWorkData *awdp,
 			      erts_aint32_t aux_work,
 			      int waiting)
 {
-#ifdef ERTS_DIRTY_SCHEDULERS
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#endif
+
     if (!erts_thr_progress_has_reached_this(haw_thr_prgr_current(awdp),
 					    awdp->misc.thr_prgr))
 	return aux_work & ~ERTS_SSI_AUX_WORK_MISC_THR_PRGR;
@@ -1978,7 +1886,6 @@ handle_misc_aux_work_thr_prgr(ErtsAuxWorkData *awdp,
 			       aux_work & ~ERTS_SSI_AUX_WORK_MISC_THR_PRGR);
 }
 
-#endif
 
 static ERTS_INLINE void
 schedule_misc_aux_work(int sched_id,
@@ -1988,11 +1895,7 @@ schedule_misc_aux_work(int sched_id,
     ErtsThrQ_t *q;
     erts_misc_aux_work_t *mawp;
 
-#ifdef ERTS_SMP
     ASSERT(0 <= sched_id && sched_id <= erts_no_schedulers);
-#else
-    ASSERT(sched_id == 1);
-#endif
 
     q = &misc_aux_work_queues[sched_id].q;
     mawp = misc_aux_work_alloc();
@@ -2036,7 +1939,6 @@ erts_schedule_multi_misc_aux_work(int ignore_self,
    }
 }
 
-#if ERTS_USE_ASYNC_READY_Q
 
 void
 erts_notify_check_async_ready_queue(void *vno)
@@ -2052,9 +1954,9 @@ handle_async_ready(ErtsAuxWorkData *awdp,
 		   int waiting)
 {
     ErtsSchedulerSleepInfo *ssi = awdp->ssi;
-#ifdef ERTS_DIRTY_SCHEDULERS
+
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#endif
+
     unset_aux_work_flags(ssi, ERTS_SSI_AUX_WORK_ASYNC_READY);
     if (erts_check_async_ready(awdp->async_ready.queue)) {
 	if (set_aux_work_flags(ssi, ERTS_SSI_AUX_WORK_ASYNC_READY)
@@ -2064,9 +1966,7 @@ handle_async_ready(ErtsAuxWorkData *awdp,
 	}
 	return aux_work;
     }
-#ifdef ERTS_SMP
     awdp->async_ready.need_thr_prgr = 0;
-#endif
     set_aux_work_flags(ssi, ERTS_SSI_AUX_WORK_ASYNC_READY_CLEAN);
     return ((aux_work & ~ERTS_SSI_AUX_WORK_ASYNC_READY)
 	    | ERTS_SSI_AUX_WORK_ASYNC_READY_CLEAN);
@@ -2079,10 +1979,8 @@ handle_async_ready_clean(ErtsAuxWorkData *awdp,
 {
     void *thr_prgr_p;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#endif
-#ifdef ERTS_SMP
+
     if (awdp->async_ready.need_thr_prgr
 	&& !erts_thr_progress_has_reached_this(haw_thr_prgr_current(awdp),
 					       awdp->async_ready.thr_prgr)) {
@@ -2091,26 +1989,20 @@ handle_async_ready_clean(ErtsAuxWorkData *awdp,
 
     awdp->async_ready.need_thr_prgr = 0;
     thr_prgr_p = (void *) &awdp->async_ready.thr_prgr;
-#else
-    thr_prgr_p = NULL;
-#endif
 
     switch (erts_async_ready_clean(awdp->async_ready.queue, thr_prgr_p)) {
     case ERTS_ASYNC_READY_CLEAN:
 	unset_aux_work_flags(awdp->ssi, ERTS_SSI_AUX_WORK_ASYNC_READY_CLEAN);
 	return aux_work & ~ERTS_SSI_AUX_WORK_ASYNC_READY_CLEAN;
-#ifdef ERTS_SMP
     case ERTS_ASYNC_READY_NEED_THR_PRGR:
 	haw_thr_prgr_soft_wakeup(awdp, awdp->async_ready.thr_prgr);
 	awdp->async_ready.need_thr_prgr = 1;
 	return aux_work & ~ERTS_SSI_AUX_WORK_ASYNC_READY_CLEAN;
-#endif
     default:
 	return aux_work;
     }
 }
 
-#endif /* ERTS_USE_ASYNC_READY_Q */
 
 
 static ERTS_INLINE erts_aint32_t
@@ -2119,9 +2011,8 @@ handle_fix_alloc(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int waiting)
     ErtsSchedulerSleepInfo *ssi = awdp->ssi;
     erts_aint32_t res;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#endif
+
     unset_aux_work_flags(ssi, (ERTS_SSI_AUX_WORK_FIX_ALLOC_LOWER_LIM
 			       | ERTS_SSI_AUX_WORK_FIX_ALLOC_DEALLOC));
     aux_work &= ~(ERTS_SSI_AUX_WORK_FIX_ALLOC_LOWER_LIM
@@ -2135,7 +2026,6 @@ handle_fix_alloc(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int waiting)
     return aux_work;
 }
 
-#ifdef ERTS_SMP
 
 void
 erts_alloc_notify_delayed_dealloc(int ix)
@@ -2169,9 +2059,9 @@ handle_delayed_dealloc(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int waitin
     ErtsThrPrgrVal wakeup = ERTS_THR_PRGR_INVALID;
     int more_work = 0;
     ERTS_MSACC_PUSH_STATE_M_X();
-#ifdef ERTS_DIRTY_SCHEDULERS
+
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#endif
+
     unset_aux_work_flags(ssi, ERTS_SSI_AUX_WORK_DD);
     ERTS_MSACC_SET_STATE_CACHED_M_X(ERTS_MSACC_STATE_ALLOC);
     erts_alloc_scheduler_handle_delayed_dealloc((void *) awdp->esdp,
@@ -2208,9 +2098,8 @@ handle_delayed_dealloc_thr_prgr(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, i
     ErtsThrPrgrVal wakeup = ERTS_THR_PRGR_INVALID;
     ErtsThrPrgrVal current = haw_thr_prgr_current(awdp);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#endif
+
     if (!erts_thr_progress_has_reached_this(current, awdp->dd.thr_prgr))
 	return aux_work & ~ERTS_SSI_AUX_WORK_DD_THR_PRGR;
 
@@ -2267,9 +2156,8 @@ handle_canceled_timers(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int waitin
     ErtsThrPrgrVal wakeup = ERTS_THR_PRGR_INVALID;
     int more_work = 0;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#endif
+
     unset_aux_work_flags(ssi, ERTS_SSI_AUX_WORK_CNCLD_TMRS);
     erts_handle_canceled_timers((void *) awdp->esdp,
 				&need_thr_progress,
@@ -2303,9 +2191,8 @@ handle_canceled_timers_thr_prgr(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, i
     ErtsThrPrgrVal wakeup = ERTS_THR_PRGR_INVALID;
     ErtsThrPrgrVal current = haw_thr_prgr_current(awdp);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#endif
+
     if (!erts_thr_progress_has_reached_this(current, awdp->cncld_tmrs.thr_prgr))
 	return aux_work & ~ERTS_SSI_AUX_WORK_CNCLD_TMRS_THR_PRGR;
 
@@ -2348,9 +2235,8 @@ handle_thr_prgr_later_op(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int wait
     int lops;
     ErtsThrPrgrVal current = haw_thr_prgr_current(awdp);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#endif
+
     for (lops = 0; lops < ERTS_MAX_THR_PRGR_LATER_OPS; lops++) {
 	ErtsThrPrgrLaterOp *lop = awdp->later_op.first;
 
@@ -2380,7 +2266,7 @@ enqueue_later_op(ErtsSchedulerData *esdp,
 		 ErtsThrPrgrLaterOp *lop)
 {
     ErtsThrPrgrVal later = erts_thr_progress_later(esdp);
-    ASSERT(esdp);
+    ASSERT(esdp && !ERTS_SCHEDULER_IS_DIRTY(esdp));
 
     lop->func = later_func;
     lop->data = later_data;
@@ -2396,20 +2282,15 @@ enqueue_later_op(ErtsSchedulerData *esdp,
     return later;
 }
 
-#endif /* ERTS_SMP */
 
 void
 erts_schedule_thr_prgr_later_op(void (*later_func)(void *),
 				void *later_data,
 				ErtsThrPrgrLaterOp *lop)
 {
-#ifndef ERTS_SMP
-    later_func(later_data);
-#else
     ErtsSchedulerData *esdp = erts_get_scheduler_data();
     ErtsThrPrgrVal later = enqueue_later_op(esdp, later_func, later_data, lop);
     haw_thr_prgr_wakeup(&esdp->aux_work_data, later);
-#endif
 }
 
 void
@@ -2418,13 +2299,9 @@ erts_schedule_thr_prgr_later_cleanup_op(void (*later_func)(void *),
 					ErtsThrPrgrLaterOp *lop,
 					UWord size)
 {
-#ifndef ERTS_SMP
-    later_func(later_data);
-#else
     ErtsSchedulerData *esdp = erts_get_scheduler_data();
     ErtsThrPrgrVal later = enqueue_later_op(esdp, later_func, later_data, lop);
     haw_thr_prgr_later_cleanup_op_wakeup(&esdp->aux_work_data, later, size);
-#endif
 }
 
 static ERTS_INLINE erts_aint32_t
@@ -2433,9 +2310,7 @@ handle_debug_wait_completed(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int w
     ErtsSchedulerSleepInfo *ssi = awdp->ssi;
     erts_aint32_t saved_aux_work, flags;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#endif
 
     flags = awdp->debug.wait_completed.flags;
 
@@ -2476,11 +2351,7 @@ setup_thr_debug_wait_completed(void *vproc)
     ErtsSchedulerData *esdp = erts_get_scheduler_data();
     ErtsAuxWorkData *awdp;
     erts_aint32_t wait_flags, aux_work_flags;
-#ifdef ERTS_SMP
     awdp = esdp ? &esdp->aux_work_data : aux_thread_aux_work_data;
-#else
-    awdp = &esdp->aux_work_data;
-#endif
 
     wait_flags = 0;
     aux_work_flags = ERTS_SSI_AUX_WORK_DEBUG_WAIT_COMPLETED;
@@ -2489,18 +2360,14 @@ setup_thr_debug_wait_completed(void *vproc)
 	erts_alloc_fix_alloc_shrink(awdp->sched_id, 0);
 	wait_flags |= (ERTS_SSI_AUX_WORK_DD
 		       | ERTS_SSI_AUX_WORK_DD_THR_PRGR);
-#ifdef ERTS_SMP
 	aux_work_flags |= ERTS_SSI_AUX_WORK_DD;
-#endif
     }
 
     if (debug_wait_completed_flags & ERTS_DEBUG_WAIT_COMPLETED_TIMER_CANCELLATIONS) {
 	wait_flags |= (ERTS_SSI_AUX_WORK_CNCLD_TMRS
 		       | ERTS_SSI_AUX_WORK_CNCLD_TMRS_THR_PRGR);
-#ifdef ERTS_SMP
 	if (awdp->esdp && !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp))
 	    aux_work_flags |= ERTS_SSI_AUX_WORK_CNCLD_TMRS;
-#endif
     }
 
     set_aux_work_flags_wakeup_nob(awdp->ssi, aux_work_flags);
@@ -2519,21 +2386,17 @@ static void later_thr_debug_wait_completed(void *vlop)
 {
     struct debug_lop *lop = vlop;
     erts_aint32_t count = (erts_aint32_t) erts_no_schedulers;
-#ifdef ERTS_SMP
     count += 1; /* aux thread */
-#endif
     if (erts_atomic32_dec_read_mb(&debug_wait_completed_count) == count) {
         /* scheduler threads */
         erts_schedule_multi_misc_aux_work(0,
                                           erts_no_schedulers,
                                           setup_thr_debug_wait_completed,
                                           lop->proc);
-#ifdef ERTS_SMP
         /* aux_thread */
         erts_schedule_misc_aux_work(0,
                                     setup_thr_debug_wait_completed,
                                     lop->proc);
-#endif
     }
     erts_free(ERTS_ALC_T_DEBUG, lop);
 }
@@ -2554,9 +2417,7 @@ erts_debug_wait_completed(Process *c_p, int flags)
 {
     /* Only one process at a time can do this */
     erts_aint32_t count = (erts_aint32_t) (2*erts_no_schedulers);
-#ifdef ERTS_SMP
     count += 1; /* aux thread */
-#endif
     if (0 == erts_atomic32_cmpxchg_mb(&debug_wait_completed_count,
 				      count,
 				      0)) {
@@ -2585,7 +2446,7 @@ notify_reap_ports_relb(void)
     }
 }
 
-erts_smp_atomic32_t erts_halt_progress;
+erts_atomic32_t erts_halt_progress;
 int erts_halt_code;
 
 static ERTS_INLINE erts_aint32_t
@@ -2594,9 +2455,9 @@ handle_reap_ports(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int waiting)
     unset_aux_work_flags(awdp->ssi, ERTS_SSI_AUX_WORK_REAP_PORTS);
     ERTS_RUNQ_FLGS_SET(awdp->esdp->run_queue, ERTS_RUNQ_FLG_HALTING);
 
-    if (erts_smp_atomic32_dec_read_acqb(&erts_halt_progress) == 0) {
+    if (erts_atomic32_dec_read_acqb(&erts_halt_progress) == 0) {
 	int i, max = erts_ptab_max(&erts_port);
-	erts_smp_atomic32_set_nob(&erts_halt_progress, 1);
+	erts_atomic32_set_nob(&erts_halt_progress, 1);
 	for (i = 0; i < max; i++) {
 	    erts_aint32_t state;
 	    Port *prt = erts_pix2port(i);
@@ -2609,21 +2470,21 @@ handle_reap_ports(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int waiting)
 
 	    /* We need to set the halt flag - get the port lock */
 
-	    erts_smp_port_lock(prt);
+	    erts_port_lock(prt);
 
 	    state = erts_atomic32_read_nob(&prt->state);
 	    if (!(state & (ERTS_PORT_SFLGS_INVALID_DRIVER_LOOKUP
 			   | ERTS_PORT_SFLG_HALT))) {
 		state = erts_atomic32_read_bor_relb(&prt->state,
 						    ERTS_PORT_SFLG_HALT);
-		erts_smp_atomic32_inc_nob(&erts_halt_progress);
+		erts_atomic32_inc_nob(&erts_halt_progress);
 		if (!(state & (ERTS_PORT_SFLG_EXITING|ERTS_PORT_SFLG_CLOSING)))
 		    erts_deliver_port_exit(prt, prt->common.id, am_killed, 0, 1);
 	    }
 
 	    erts_port_release(prt);
 	}
-	if (erts_smp_atomic32_dec_read_nob(&erts_halt_progress) == 0) {
+	if (erts_atomic32_dec_read_nob(&erts_halt_progress) == 0) {
 	    erts_flush_async_exit(erts_halt_code, "");
 	}
     }
@@ -2684,7 +2545,6 @@ handle_mseg_cache_check(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int waiti
 
 #endif
 
-#ifdef ERTS_SMP
 
 static ERTS_INLINE erts_aint32_t
 handle_pending_exiters(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int waiting)
@@ -2695,10 +2555,10 @@ handle_pending_exiters(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int waitin
     rq = awdp->esdp->run_queue;
     unset_aux_work_flags(awdp->ssi, ERTS_SSI_AUX_WORK_PENDING_EXITERS);
 
-    erts_smp_runq_lock(rq);
+    erts_runq_lock(rq);
     pnd_xtrs = rq->procs.pending_exiters;
     rq->procs.pending_exiters = NULL;
-    erts_smp_runq_unlock(rq);
+    erts_runq_unlock(rq);
 
     if (erts_proclist_fetch(&pnd_xtrs, NULL))
 	do_handle_pending_exiters(pnd_xtrs);
@@ -2706,7 +2566,6 @@ handle_pending_exiters(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int waitin
     return aux_work & ~ERTS_SSI_AUX_WORK_PENDING_EXITERS;
 }
 
-#endif
 
 static ERTS_INLINE erts_aint32_t
 handle_setup_aux_work_timer(ErtsAuxWorkData *awdp, erts_aint32_t aux_work, int waiting)
@@ -2738,9 +2597,7 @@ handle_aux_work(ErtsAuxWorkData *awdp, erts_aint32_t orig_aux_work, int waiting)
     ERTS_MSACC_PUSH_AND_SET_STATE_M(ERTS_MSACC_STATE_AUX);
 
     ASSERT(!awdp->esdp || !ERTS_SCHEDULER_IS_DIRTY(awdp->esdp));
-#ifdef ERTS_SMP
     haw_thr_prgr_current_reset(awdp);
-#endif
 
     ERTS_DBG_CHK_AUX_WORK_VAL(aux_work);
     ASSERT(aux_work);
@@ -2759,7 +2616,6 @@ handle_aux_work(ErtsAuxWorkData *awdp, erts_aint32_t orig_aux_work, int waiting)
      * Keep ERTS_SSI_AUX_WORK flags in expected frequency order relative
      * eachother. Most frequent first.
      */
-#ifdef ERTS_SMP
     HANDLE_AUX_WORK(ERTS_SSI_AUX_WORK_DELAYED_AW_WAKEUP,
 		    handle_delayed_aux_work_wakeup);
     HANDLE_AUX_WORK(ERTS_SSI_AUX_WORK_DD,
@@ -2767,13 +2623,11 @@ handle_aux_work(ErtsAuxWorkData *awdp, erts_aint32_t orig_aux_work, int waiting)
     /* DD must be before DD_THR_PRGR */
     HANDLE_AUX_WORK(ERTS_SSI_AUX_WORK_DD_THR_PRGR,
 		    handle_delayed_dealloc_thr_prgr);
-#endif
 
     HANDLE_AUX_WORK((ERTS_SSI_AUX_WORK_FIX_ALLOC_LOWER_LIM
 		     | ERTS_SSI_AUX_WORK_FIX_ALLOC_DEALLOC),
 		    handle_fix_alloc);
 
-#ifdef ERTS_SMP
     HANDLE_AUX_WORK(ERTS_SSI_AUX_WORK_THR_PRGR_LATER_OP,
 		    handle_thr_prgr_later_op);
     HANDLE_AUX_WORK(ERTS_SSI_AUX_WORK_CNCLD_TMRS,
@@ -2781,28 +2635,21 @@ handle_aux_work(ErtsAuxWorkData *awdp, erts_aint32_t orig_aux_work, int waiting)
     /* CNCLD_TMRS must be before CNCLD_TMRS_THR_PRGR */
     HANDLE_AUX_WORK(ERTS_SSI_AUX_WORK_CNCLD_TMRS_THR_PRGR,
 		    handle_canceled_timers_thr_prgr);
-#endif
 
-#if ERTS_USE_ASYNC_READY_Q
     HANDLE_AUX_WORK(ERTS_SSI_AUX_WORK_ASYNC_READY,
 		    handle_async_ready);
     /* ASYNC_READY must be before ASYNC_READY_CLEAN */
     HANDLE_AUX_WORK(ERTS_SSI_AUX_WORK_ASYNC_READY_CLEAN,
 		    handle_async_ready_clean);
-#endif
 
-#ifdef ERTS_SMP
     HANDLE_AUX_WORK(ERTS_SSI_AUX_WORK_MISC_THR_PRGR,
 		    handle_misc_aux_work_thr_prgr);
-#endif
     /* MISC_THR_PRGR must be before MISC */
     HANDLE_AUX_WORK(ERTS_SSI_AUX_WORK_MISC,
 		    handle_misc_aux_work);
 
-#ifdef ERTS_SMP
     HANDLE_AUX_WORK(ERTS_SSI_AUX_WORK_PENDING_EXITERS,
 		    handle_pending_exiters);
-#endif
 
     HANDLE_AUX_WORK(ERTS_SSI_AUX_WORK_SET_TMO,
 		    handle_setup_aux_work_timer);
@@ -2828,10 +2675,8 @@ handle_aux_work(ErtsAuxWorkData *awdp, erts_aint32_t orig_aux_work, int waiting)
 
     ERTS_DBG_CHK_AUX_WORK_VAL(aux_work);
 
-#ifdef ERTS_SMP
     if (waiting && !aux_work)
 	haw_thr_prgr_current_check_progress(awdp);
-#endif
 
     ERTS_MSACC_UPDATE_CACHE();
     ERTS_MSACC_POP_STATE_M();
@@ -2930,11 +2775,7 @@ aux_work_timeout(void *vesdp)
     ASSERT(esdp == (ErtsSchedulerData *) vesdp);
 #endif
 
-#ifdef ERTS_SMP
     i = 0;
-#else
-    i = 1;
-#endif
 
     for (; i <= erts_no_schedulers; i++) {
 	erts_aint32_t type;
@@ -2968,9 +2809,6 @@ erts_set_aux_work_timeout(int ix, erts_aint32_t type, int enable)
 {
     erts_aint32_t old, refc;
 
-#ifndef ERTS_SMP
-    ix = 1;
-#endif
 
     ERTS_DBG_CHK_AUX_WORK_VAL(type);
     ERTS_DBG_CHK_AUX_WORK_VAL(erts_atomic32_read_nob(&aux_work_tmo->type[ix]));
@@ -2997,36 +2835,6 @@ erts_set_aux_work_timeout(int ix, erts_aint32_t type, int enable)
     return old;
 }
 
-
-
-static ERTS_INLINE void
-sched_waiting_sys(Uint no, ErtsRunQueue *rq)
-{
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
-    ASSERT(rq->waiting >= 0);
-    (void) ERTS_RUNQ_FLGS_SET(rq, (ERTS_RUNQ_FLG_OUT_OF_WORK
-				   | ERTS_RUNQ_FLG_HALFTIME_OUT_OF_WORK));
-    rq->waiting++;
-    rq->waiting *= -1;
-    rq->woken = 0;
-    if (erts_system_profile_flags.scheduler)
-	profile_scheduler(make_small(no), am_inactive);
-}
-
-static ERTS_INLINE void
-sched_active_sys(Uint no, ErtsRunQueue *rq)
-{
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
-#ifdef ERTS_DIRTY_SCHEDULERS
-    ASSERT(!ERTS_RUNQ_IX_IS_DIRTY(rq->ix));
-#endif
-    ASSERT(rq->waiting < 0);
-    rq->waiting *= -1;
-    rq->waiting--;
-    if (erts_system_profile_flags.scheduler)
-	profile_scheduler(make_small(no), am_active);
-}
-
 Uint
 erts_active_schedulers(void)
 {
@@ -3037,64 +2845,10 @@ erts_active_schedulers(void)
     return as;
 }
 
-#ifdef ERTS_SMP
-
-static ERTS_INLINE void
-clear_sys_scheduling(void)
-{
-    erts_smp_atomic32_set_mb(&doing_sys_schedule, 0);
-}
-
-static ERTS_INLINE int
-try_set_sys_scheduling(void)
-{
-    return 0 == erts_smp_atomic32_cmpxchg_acqb(&doing_sys_schedule, 1, 0);
-}
-
-#endif
-
-static ERTS_INLINE int
-prepare_for_sys_schedule(int non_blocking)
-{
-    if (non_blocking && erts_eager_check_io) {
-#ifdef ERTS_SMP
-	return try_set_sys_scheduling();
-#else
-	return 1;
-#endif
-    }
-    else {
-#ifdef ERTS_SMP
-	while (!erts_port_task_have_outstanding_io_tasks()
-	       && try_set_sys_scheduling()) {
-	    if (!erts_port_task_have_outstanding_io_tasks())
-		return 1;
-	    clear_sys_scheduling();
-	}
-	return 0;
-#else
-	return !erts_port_task_have_outstanding_io_tasks();
-#endif
-    }
-}
-
-#ifdef ERTS_SMP
-
-static ERTS_INLINE void
-sched_change_waiting_sys_to_waiting(Uint no, ErtsRunQueue *rq)
-{
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
-#ifdef ERTS_DIRTY_SCHEDULERS
-    ASSERT(!ERTS_RUNQ_IX_IS_DIRTY(rq->ix));
-#endif
-    ASSERT(rq->waiting < 0);
-    rq->waiting *= -1;
-}
-
 static ERTS_INLINE void
 sched_waiting(Uint no, ErtsRunQueue *rq)
 {
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
     (void) ERTS_RUNQ_FLGS_SET(rq, (ERTS_RUNQ_FLG_OUT_OF_WORK
 				   | ERTS_RUNQ_FLG_HALFTIME_OUT_OF_WORK));
     if (rq->waiting < 0)
@@ -3109,7 +2863,7 @@ sched_waiting(Uint no, ErtsRunQueue *rq)
 static ERTS_INLINE void
 sched_active(Uint no, ErtsRunQueue *rq)
 {
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
     if (rq->waiting < 0)
 	rq->waiting++;
     else
@@ -3123,7 +2877,7 @@ empty_runq_aux(ErtsRunQueue *rq, Uint32 old_flags)
 {
     if (!ERTS_RUNQ_IX_IS_DIRTY(rq->ix) && old_flags & ERTS_RUNQ_FLG_NONEMPTY) {
 #ifdef DEBUG
-	erts_aint32_t empty = erts_smp_atomic32_read_nob(&no_empty_run_queues);
+	erts_aint32_t empty = erts_atomic32_read_nob(&no_empty_run_queues);
 	/*
 	 * For a short period of time no_empty_run_queues may have
 	 * been increased twice for a specific run queue.
@@ -3131,9 +2885,9 @@ empty_runq_aux(ErtsRunQueue *rq, Uint32 old_flags)
 	ASSERT(0 <= empty && empty < 2*erts_no_run_queues);
 #endif
 	if (!erts_runq_supervision_interval)
-	    erts_smp_atomic32_inc_relb(&no_empty_run_queues);
+	    erts_atomic32_inc_relb(&no_empty_run_queues);
 	else {
-	    erts_smp_atomic32_inc_mb(&no_empty_run_queues);
+	    erts_atomic32_inc_mb(&no_empty_run_queues);
 	    if (erts_atomic_read_nob(&runq_supervisor_sleeping))
 		ethr_event_set(&runq_supervision_event);
 	}
@@ -3163,7 +2917,7 @@ non_empty_runq(ErtsRunQueue *rq)
     Uint32 old_flags = ERTS_RUNQ_FLGS_SET(rq, ERTS_RUNQ_FLG_NONEMPTY);
     if (!ERTS_RUNQ_IX_IS_DIRTY(rq->ix) && (!(old_flags & ERTS_RUNQ_FLG_NONEMPTY))) {
 #ifdef DEBUG
-	erts_aint32_t empty = erts_smp_atomic32_read_nob(&no_empty_run_queues);
+	erts_aint32_t empty = erts_atomic32_read_nob(&no_empty_run_queues);
 	/*
 	 * For a short period of time no_empty_run_queues may have
 	 * been increased twice for a specific run queue.
@@ -3171,10 +2925,10 @@ non_empty_runq(ErtsRunQueue *rq)
 	ASSERT(0 < empty && empty <= 2*erts_no_run_queues);
 #endif
 	if (!erts_runq_supervision_interval)
-	    erts_smp_atomic32_dec_relb(&no_empty_run_queues);
+	    erts_atomic32_dec_relb(&no_empty_run_queues);
 	else {
 	    erts_aint32_t no;
-	    no = erts_smp_atomic32_dec_read_mb(&no_empty_run_queues);
+	    no = erts_atomic32_dec_read_mb(&no_empty_run_queues);
 	    if (no > 0 && erts_atomic_read_nob(&runq_supervisor_sleeping))
 		ethr_event_set(&runq_supervision_event);
 	}
@@ -3203,7 +2957,7 @@ sched_prep_spin_wait(ErtsSchedulerSleepInfo *ssi)
     do {
         nflgs = (xflgs & ERTS_SSI_FLG_MSB_EXEC);
         nflgs |= ERTS_SSI_FLG_SLEEPING|ERTS_SSI_FLG_WAITING;
-	oflgs = erts_smp_atomic32_cmpxchg_acqb(&ssi->flags, nflgs, xflgs);
+	oflgs = erts_atomic32_cmpxchg_acqb(&ssi->flags, nflgs, xflgs);
 	if (oflgs == xflgs)
 	    return nflgs;
 	xflgs = oflgs;
@@ -3220,7 +2974,7 @@ sched_prep_cont_spin_wait(ErtsSchedulerSleepInfo *ssi)
     erts_aint32_t xflgs = ERTS_SSI_FLG_WAITING;
 
     do {
-	oflgs = erts_smp_atomic32_cmpxchg_acqb(&ssi->flags, nflgs, xflgs);
+	oflgs = erts_atomic32_cmpxchg_acqb(&ssi->flags, nflgs, xflgs);
 	if (oflgs == xflgs)
 	    return nflgs;
 	xflgs = oflgs;
@@ -3237,7 +2991,7 @@ sched_spin_wait(ErtsSchedulerSleepInfo *ssi, int spincount)
     erts_aint32_t flgs;
 
     do {
-	flgs = erts_smp_atomic32_read_acqb(&ssi->flags);
+	flgs = erts_atomic32_read_acqb(&ssi->flags);
 	if ((flgs & (ERTS_SSI_FLG_SLEEPING|ERTS_SSI_FLG_WAITING))
 	    != (ERTS_SSI_FLG_SLEEPING|ERTS_SSI_FLG_WAITING)) {
 	    break;
@@ -3262,11 +3016,11 @@ sched_set_sleeptype(ErtsSchedulerSleepInfo *ssi, erts_aint32_t sleep_type)
 	erts_tse_reset(ssi->event);
     else {
 	ASSERT(sleep_type == ERTS_SSI_FLG_POLL_SLEEPING);
-	erts_sys_schedule_interrupt(0);
+        erts_check_io_interrupt(ssi->psi, 0);
     }
 
     while (1) {
-	oflgs = erts_smp_atomic32_cmpxchg_acqb(&ssi->flags, nflgs, xflgs);
+	oflgs = erts_atomic32_cmpxchg_acqb(&ssi->flags, nflgs, xflgs);
 	if (oflgs == xflgs)
 	    return nflgs;
 	if ((oflgs & (ERTS_SSI_FLG_SLEEPING|ERTS_SSI_FLG_WAITING))
@@ -3293,7 +3047,7 @@ static void
 thr_prgr_prep_wait(void *vssi)
 {
     ErtsSchedulerSleepInfo *ssi = (ErtsSchedulerSleepInfo *) vssi;
-    erts_smp_atomic32_read_bor_acqb(&ssi->flags,
+    erts_atomic32_read_bor_acqb(&ssi->flags,
 				    ERTS_SSI_FLG_SLEEPING);
 }
 
@@ -3308,7 +3062,7 @@ thr_prgr_wait(void *vssi)
     while (1) {
 	erts_aint32_t aflgs, nflgs;
 	nflgs = xflgs | ERTS_SSI_FLG_TSE_SLEEPING;
-	aflgs = erts_smp_atomic32_cmpxchg_acqb(&ssi->flags, nflgs, xflgs);
+	aflgs = erts_atomic32_cmpxchg_acqb(&ssi->flags, nflgs, xflgs);
 	if (aflgs == xflgs) {
 	    erts_tse_wait(ssi->event);
 	    break;
@@ -3323,13 +3077,19 @@ static void
 thr_prgr_fin_wait(void *vssi)
 {
     ErtsSchedulerSleepInfo *ssi = (ErtsSchedulerSleepInfo *) vssi;
-    erts_smp_atomic32_read_band_nob(&ssi->flags,
+    erts_atomic32_read_band_nob(&ssi->flags,
 				    ~(ERTS_SSI_FLG_SLEEPING
 				      | ERTS_SSI_FLG_TSE_SLEEPING));
 }
 
 static void init_aux_work_data(ErtsAuxWorkData *awdp, ErtsSchedulerData *esdp, char *dawwp);
 
+void
+erts_aux_thread_poke()
+{
+    erts_sched_poke(ERTS_SCHED_SLEEP_INFO_IX(-1));
+}
+
 static void *
 aux_thread(void *unused)
 {
@@ -3338,6 +3098,7 @@ aux_thread(void *unused)
     erts_aint32_t aux_work;
     ErtsThrPrgrCallbacks callbacks;
     int thr_prgr_active = 1;
+    ERTS_MSACC_DECLARE_CACHE();
 
 #ifdef ERTS_ENABLE_LOCK_CHECK
     {
@@ -3346,6 +3107,7 @@ aux_thread(void *unused)
     }
 #endif
 
+    erts_port_task_pre_alloc_init_thread();
     ssi->event = erts_tse_fetch();
 
     erts_msacc_init_thread("aux", 1, 1);
@@ -3360,9 +3122,14 @@ aux_thread(void *unused)
     init_aux_work_data(awdp, NULL, NULL);
     awdp->ssi = ssi;
 
+#if ERTS_POLL_USE_FALLBACK
+    ssi->psi = erts_create_pollset_thread(-1);
+#endif
 
     sched_prep_spin_wait(ssi);
 
+    ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_OTHER);
+
     while (1) {
 	erts_aint32_t flgs;
 
@@ -3371,30 +3138,54 @@ aux_thread(void *unused)
 	    if (!thr_prgr_active)
 		erts_thr_progress_active(NULL, thr_prgr_active = 1);
 	    aux_work = handle_aux_work(awdp, aux_work, 1);
+            ERTS_MSACC_UPDATE_CACHE();
 	    if (aux_work && erts_thr_progress_update(NULL))
 		erts_thr_progress_leader_update(NULL);
 	}
 
 	if (!aux_work) {
+
+#ifdef ERTS_BREAK_REQUESTED
+            if (ERTS_BREAK_REQUESTED)
+                erts_do_break_handling();
+#endif
+
 	    if (thr_prgr_active)
 		erts_thr_progress_active(NULL, thr_prgr_active = 0);
-	    erts_thr_progress_prepare_wait(NULL);
+
+#if ERTS_POLL_USE_FALLBACK
 
 	    flgs = sched_spin_wait(ssi, 0);
 
 	    if (flgs & ERTS_SSI_FLG_SLEEPING) {
 		ASSERT(flgs & ERTS_SSI_FLG_WAITING);
+		flgs = sched_set_sleeptype(ssi, ERTS_SSI_FLG_POLL_SLEEPING);
+		if (flgs & ERTS_SSI_FLG_SLEEPING) {
+		    ASSERT(flgs & ERTS_SSI_FLG_POLL_SLEEPING);
+		    ASSERT(flgs & ERTS_SSI_FLG_WAITING);
+                    erts_check_io(ssi->psi);
+		}
+            }
+#else
+            erts_thr_progress_prepare_wait(NULL);
+
+	    flgs = sched_spin_wait(ssi, 0);
+
+	    if (flgs & ERTS_SSI_FLG_SLEEPING) {
 		flgs = sched_set_sleeptype(ssi, ERTS_SSI_FLG_TSE_SLEEPING);
 		if (flgs & ERTS_SSI_FLG_SLEEPING) {
-		    int res;
+                    int res;
 		    ASSERT(flgs & ERTS_SSI_FLG_TSE_SLEEPING);
 		    ASSERT(flgs & ERTS_SSI_FLG_WAITING);
-		    do {
-			res = erts_tse_wait(ssi->event);
-		    } while (res == EINTR);
+                    ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_SLEEP);
+                    do {
+                        res = erts_tse_wait(ssi->event);
+                    } while (res == EINTR);
+                    ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_OTHER);
 		}
-	    }
-	    erts_thr_progress_finalize_wait(NULL);
+            }
+            erts_thr_progress_finalize_wait(NULL);
+#endif
 	}
 
 	flgs = sched_prep_spin_wait(ssi);
@@ -3402,9 +3193,79 @@ aux_thread(void *unused)
     return NULL;
 }
 
-static void suspend_scheduler(ErtsSchedulerData *esdp);
+static void *
+poll_thread(void *arg)
+{
+    int id = (int)(UWord)arg;
+    ErtsAuxWorkData *awdp = poll_thread_aux_work_data+id;
+    ErtsSchedulerSleepInfo *ssi = ERTS_POLL_THREAD_SLEEP_INFO_IX(id);
+    erts_aint32_t aux_work;
+    ErtsThrPrgrCallbacks callbacks;
+    int thr_prgr_active = 1;
+    struct erts_poll_thread *psi = erts_create_pollset_thread(id);
+    ERTS_MSACC_DECLARE_CACHE();
+
+#ifdef ERTS_ENABLE_LOCK_CHECK
+    {
+	char buf[] = "poll_thread";
+	erts_lc_set_thread_name(buf);
+    }
+#endif
+
+    erts_port_task_pre_alloc_init_thread();
+    ssi->event = erts_tse_fetch();
+
+    erts_msacc_init_thread("poll", id, 0);
+
+    callbacks.arg = (void *) ssi;
+    callbacks.wakeup = thr_prgr_wakeup;
+    callbacks.prepare_wait = thr_prgr_prep_wait;
+    callbacks.wait = thr_prgr_wait;
+    callbacks.finalize_wait = thr_prgr_fin_wait;
+
+    erts_thr_progress_register_managed_thread(NULL, &callbacks, 0);
+    init_aux_work_data(awdp, NULL, NULL);
+    awdp->ssi = ssi;
+    ssi->psi = psi;
+
+    sched_prep_spin_wait(ssi);
+
+    ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_OTHER);
+
+    while (1) {
+	erts_aint32_t flgs;
+
+	aux_work = erts_atomic32_read_acqb(&ssi->aux_work);
+	if (aux_work) {
+	    if (!thr_prgr_active)
+		erts_thr_progress_active(NULL, thr_prgr_active = 1);
+	    aux_work = handle_aux_work(awdp, aux_work, 1);
+            ERTS_MSACC_UPDATE_CACHE();
+	    if (aux_work && erts_thr_progress_update(NULL))
+		erts_thr_progress_leader_update(NULL);
+	}
 
-#endif /* ERTS_SMP */
+	if (!aux_work) {
+	    if (thr_prgr_active)
+		erts_thr_progress_active(NULL, thr_prgr_active = 0);
+
+	    flgs = sched_spin_wait(ssi, 0);
+
+	    if (flgs & ERTS_SSI_FLG_SLEEPING) {
+		ASSERT(flgs & ERTS_SSI_FLG_WAITING);
+		flgs = sched_set_sleeptype(ssi, ERTS_SSI_FLG_POLL_SLEEPING);
+		if (flgs & ERTS_SSI_FLG_SLEEPING) {
+		    ASSERT(flgs & ERTS_SSI_FLG_POLL_SLEEPING);
+		    ASSERT(flgs & ERTS_SSI_FLG_WAITING);
+                    erts_check_io(psi);
+		}
+	    }
+	}
+
+	flgs = sched_prep_spin_wait(ssi);
+    }
+    return NULL;
+}
 
 static void
 scheduler_wait(int *fcalls, ErtsSchedulerData *esdp, ErtsRunQueue *rq)
@@ -3413,386 +3274,168 @@ scheduler_wait(int *fcalls, ErtsSchedulerData *esdp, ErtsRunQueue *rq)
     ErtsSchedulerSleepInfo *ssi = esdp->ssi;
     int spincount;
     erts_aint32_t aux_work = 0;
-#ifdef ERTS_SMP
     int thr_prgr_active = 1;
     erts_aint32_t flgs;
-#endif
     ERTS_MSACC_PUSH_STATE();
-#ifdef ERTS_SMP
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (ERTS_RUNQ_IX_IS_DIRTY(rq->ix))
-	erts_smp_spin_lock(&rq->sleepers.lock);
-#endif
+	erts_spin_lock(&rq->sleepers.lock);
     flgs = sched_prep_spin_wait(ssi);
     if (flgs & ERTS_SSI_FLG_SUSPENDED) {
 	/* Go suspend instead... */
-#ifdef ERTS_DIRTY_SCHEDULERS
 	if (ERTS_RUNQ_IX_IS_DIRTY(rq->ix))
-	    erts_smp_spin_unlock(&rq->sleepers.lock);
-#endif
+	    erts_spin_unlock(&rq->sleepers.lock);
 	return;
     }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (ERTS_RUNQ_IX_IS_DIRTY(rq->ix)) {
 	ssi->prev = NULL;
 	ssi->next = rq->sleepers.list;
 	if (rq->sleepers.list)
 	    rq->sleepers.list->prev = ssi;
 	rq->sleepers.list = ssi;
-	erts_smp_spin_unlock(&rq->sleepers.lock);
+	erts_spin_unlock(&rq->sleepers.lock);
         dirty_active(esdp, -1);
     }
-#endif
 
-    /*
-     * If all schedulers are waiting, one of them *should*
-     * be waiting in erl_sys_schedule()
-     */
+    sched_waiting(esdp->no, rq);
 
-    if (ERTS_SCHEDULER_IS_DIRTY(esdp) || !prepare_for_sys_schedule(0)) {
+    erts_runq_unlock(rq);
 
-	sched_waiting(esdp->no, rq);
+    spincount = sched_busy_wait.tse;
 
-	erts_smp_runq_unlock(rq);
-
-	spincount = sched_busy_wait.tse;
-
-    tse_wait:
-
-	if (ERTS_SCHEDULER_IS_DIRTY(esdp))
-	    dirty_sched_wall_time_change(esdp, working = 0);
-        else if (thr_prgr_active != working)
-	    sched_wall_time_change(esdp, working = thr_prgr_active);
-
-	while (1) {
-	    ErtsMonotonicTime current_time = 0;
-
-	    aux_work = erts_atomic32_read_acqb(&ssi->aux_work);
-	    if (aux_work && !ERTS_SCHEDULER_IS_DIRTY(esdp)) {
-		if (!thr_prgr_active) {
-		    erts_thr_progress_active(esdp, thr_prgr_active = 1);
-		    sched_wall_time_change(esdp, 1);
-		}
-		aux_work = handle_aux_work(&esdp->aux_work_data, aux_work, 1);
-                ERTS_MSACC_UPDATE_CACHE();
-		if (aux_work && erts_thr_progress_update(esdp))
-		    erts_thr_progress_leader_update(esdp);
-	    }
-
-	    if (aux_work) {
-		if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
-		    flgs = erts_smp_atomic32_read_acqb(&ssi->flags);
-		    current_time = erts_get_monotonic_time(esdp);
-		    if (current_time >= erts_next_timeout_time(esdp->next_tmo_ref)) {
-			if (!thr_prgr_active) {
-			    erts_thr_progress_active(esdp, thr_prgr_active = 1);
-			    sched_wall_time_change(esdp, 1);
-			}
-			erts_bump_timers(esdp->timer_wheel, current_time);
-		    }
-		}
-	    }
-	    else {
-		ErtsMonotonicTime timeout_time;
-		int do_timeout = 0;
-		if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
-		    timeout_time = erts_check_next_timeout_time(esdp);
-		    current_time = erts_get_monotonic_time(esdp);
-		    do_timeout = (current_time >= timeout_time);
-		} else {
-		    current_time = 0;
-		    timeout_time = ERTS_MONOTONIC_TIME_MAX;
-		}
-		if (do_timeout) {
-		    if (!thr_prgr_active) {
-			erts_thr_progress_active(esdp, thr_prgr_active = 1);
-			sched_wall_time_change(esdp, 1);
-		    }
-		}
-		else {
-		    if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
-			if (thr_prgr_active) {
-			    erts_thr_progress_active(esdp, thr_prgr_active = 0);
-			    sched_wall_time_change(esdp, 0);
-			}
-			erts_thr_progress_prepare_wait(esdp);
-		    }
+    if (ERTS_SCHEDULER_IS_DIRTY(esdp))
+        dirty_sched_wall_time_change(esdp, working = 0);
+    else if (thr_prgr_active != working)
+        sched_wall_time_change(esdp, working = thr_prgr_active);
 
-		    flgs = sched_spin_wait(ssi, spincount);
-		    if (flgs & ERTS_SSI_FLG_SLEEPING) {
-			ASSERT(flgs & ERTS_SSI_FLG_WAITING);
-			flgs = sched_set_sleeptype(ssi, ERTS_SSI_FLG_TSE_SLEEPING);
-			if (flgs & ERTS_SSI_FLG_SLEEPING) {
-			    int res;
-			    ASSERT(flgs & ERTS_SSI_FLG_TSE_SLEEPING);
-			    ASSERT(flgs & ERTS_SSI_FLG_WAITING);
-			    current_time = ERTS_SCHEDULER_IS_DIRTY(esdp) ? 0 :
-				erts_get_monotonic_time(esdp);
-			    do {
-				Sint64 timeout;
-				if (current_time >= timeout_time)
-				    break;
-				if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
-				    timeout = ERTS_MONOTONIC_TO_NSEC(timeout_time
-								     - current_time
-								     - 1) + 1;
-				} else
-				    timeout = -1;
-                                ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_SLEEP);
-				res = erts_tse_twait(ssi->event, timeout);
-                                ERTS_MSACC_POP_STATE();
-				current_time = ERTS_SCHEDULER_IS_DIRTY(esdp) ? 0 :
-				    erts_get_monotonic_time(esdp);
-			    } while (res == EINTR);
-			}
-		    }
-		    if (!ERTS_SCHEDULER_IS_DIRTY(esdp))
-			erts_thr_progress_finalize_wait(esdp);
-		}
-		if (!ERTS_SCHEDULER_IS_DIRTY(esdp) && current_time >= timeout_time)
-		    erts_bump_timers(esdp->timer_wheel, current_time);
-	    }
+    while (1) {
+        ErtsMonotonicTime current_time = 0;
 
-	    if (!(flgs & ERTS_SSI_FLG_WAITING)) {
-		ASSERT(!(flgs & ERTS_SSI_FLG_SLEEPING));
-		break;
-	    }
+        aux_work = erts_atomic32_read_acqb(&ssi->aux_work);
+        if (aux_work && !ERTS_SCHEDULER_IS_DIRTY(esdp)) {
+            if (!thr_prgr_active) {
+                erts_thr_progress_active(esdp, thr_prgr_active = 1);
+                sched_wall_time_change(esdp, 1);
+            }
+            aux_work = handle_aux_work(&esdp->aux_work_data, aux_work, 1);
+            ERTS_MSACC_UPDATE_CACHE();
+            if (aux_work && erts_thr_progress_update(esdp))
+                erts_thr_progress_leader_update(esdp);
+        }
 
-	    flgs = sched_prep_cont_spin_wait(ssi);
-	    spincount = sched_busy_wait.aux_work;
+        if (aux_work) {
+            if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
+                flgs = erts_atomic32_read_acqb(&ssi->flags);
+                current_time = erts_get_monotonic_time(esdp);
+                if (current_time >= erts_next_timeout_time(esdp->next_tmo_ref)) {
+                    if (!thr_prgr_active) {
+                        erts_thr_progress_active(esdp, thr_prgr_active = 1);
+                        sched_wall_time_change(esdp, 1);
+                    }
+                    erts_bump_timers(esdp->timer_wheel, current_time);
+                }
+            }
+        }
+        else {
+            ErtsMonotonicTime timeout_time;
+            int do_timeout = 0;
+            if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
+                timeout_time = erts_check_next_timeout_time(esdp);
+                current_time = erts_get_monotonic_time(esdp);
+                do_timeout = (current_time >= timeout_time);
+            } else {
+                current_time = 0;
+                timeout_time = ERTS_MONOTONIC_TIME_MAX;
+            }
+            if (do_timeout) {
+                if (!thr_prgr_active) {
+                    erts_thr_progress_active(esdp, thr_prgr_active = 1);
+                    sched_wall_time_change(esdp, 1);
+                }
+            }
+            else {
+                if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
+                    if (thr_prgr_active) {
+                        erts_thr_progress_active(esdp, thr_prgr_active = 0);
+                        sched_wall_time_change(esdp, 0);
+                    }
+                    erts_thr_progress_prepare_wait(esdp);
+                }
 
-	    if (!(flgs & ERTS_SSI_FLG_WAITING)) {
-		ASSERT(!(flgs & ERTS_SSI_FLG_SLEEPING));
-		break;
-	    }
+                flgs = sched_spin_wait(ssi, spincount);
+                if (flgs & ERTS_SSI_FLG_SLEEPING) {
+                    ASSERT(flgs & ERTS_SSI_FLG_WAITING);
+                    flgs = sched_set_sleeptype(ssi, ERTS_SSI_FLG_TSE_SLEEPING);
+                    if (flgs & ERTS_SSI_FLG_SLEEPING) {
+                        int res;
+                        ASSERT(flgs & ERTS_SSI_FLG_TSE_SLEEPING);
+                        ASSERT(flgs & ERTS_SSI_FLG_WAITING);
+                        current_time = ERTS_SCHEDULER_IS_DIRTY(esdp) ? 0 :
+                            erts_get_monotonic_time(esdp);
+                        do {
+                            Sint64 timeout;
+                            if (current_time >= timeout_time)
+                                break;
+                            if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
+                                timeout = ERTS_MONOTONIC_TO_NSEC(timeout_time
+                                                                 - current_time
+                                                                 - 1) + 1;
+                            } else
+                                timeout = -1;
+                            ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_SLEEP);
+                            res = erts_tse_twait(ssi->event, timeout);
+                            ERTS_MSACC_POP_STATE();
+                            current_time = ERTS_SCHEDULER_IS_DIRTY(esdp) ? 0 :
+                                erts_get_monotonic_time(esdp);
+                        } while (res == EINTR);
+                    }
+                }
+                if (!ERTS_SCHEDULER_IS_DIRTY(esdp))
+                    erts_thr_progress_finalize_wait(esdp);
+            }
+            if (!ERTS_SCHEDULER_IS_DIRTY(esdp) && current_time >= timeout_time)
+                erts_bump_timers(esdp->timer_wheel, current_time);
+        }
 
-	}
+        if (!(flgs & ERTS_SSI_FLG_WAITING)) {
+            ASSERT(!(flgs & ERTS_SSI_FLG_SLEEPING));
+            break;
+        }
 
-	if (flgs & ~(ERTS_SSI_FLG_SUSPENDED|ERTS_SSI_FLG_MSB_EXEC))
-	    erts_smp_atomic32_read_band_nob(&ssi->flags,
-                                            (ERTS_SSI_FLG_SUSPENDED
-                                             | ERTS_SSI_FLG_MSB_EXEC));
+        flgs = sched_prep_cont_spin_wait(ssi);
+        spincount = sched_busy_wait.aux_work;
 
-	if (ERTS_SCHEDULER_IS_DIRTY(esdp))
-	    dirty_sched_wall_time_change(esdp, working = 1);
-        else if (!thr_prgr_active) {
-	    erts_thr_progress_active(esdp, thr_prgr_active = 1);
-	    sched_wall_time_change(esdp, 1);
+        if (!(flgs & ERTS_SSI_FLG_WAITING)) {
+            ASSERT(!(flgs & ERTS_SSI_FLG_SLEEPING));
+            break;
         }
 
-	erts_smp_runq_lock(rq);
-	sched_active(esdp->no, rq);
-
     }
-    else
-#endif
-    {
-
-	erts_smp_atomic32_set_relb(&function_calls, 0);
-	*fcalls = 0;
-
-#ifdef ERTS_DIRTY_SCHEDULERS
-	ASSERT(!ERTS_SCHEDULER_IS_DIRTY(esdp));
-#endif
-	sched_waiting_sys(esdp->no, rq);
-
-	erts_smp_runq_unlock(rq);
 
-	ASSERT(working);
-	sched_wall_time_change(esdp, working = 0);
+    if (flgs & ~(ERTS_SSI_FLG_SUSPENDED|ERTS_SSI_FLG_MSB_EXEC))
+        erts_atomic32_read_band_nob(&ssi->flags,
+                                        (ERTS_SSI_FLG_SUSPENDED
+                                         | ERTS_SSI_FLG_MSB_EXEC));
 
-	spincount = sched_busy_wait.sys_schedule;
-	if (spincount == 0)
-	    goto sys_aux_work;
-
-	while (spincount-- > 0) {
-	    ErtsMonotonicTime current_time;
-
-	sys_poll_aux_work:
-
-	    if (working)
-		sched_wall_time_change(esdp, working = 0);
-
-	    ERTS_MSACC_SET_STATE_CACHED_M(ERTS_MSACC_STATE_CHECK_IO);
-
-	    ASSERT(!erts_port_task_have_outstanding_io_tasks());
-            LTTNG2(scheduler_poll, esdp->no, 1);
-	    erl_sys_schedule(1); /* Might give us something to do */
-
-	    ERTS_MSACC_POP_STATE_M();
-
-	    if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
-		current_time = erts_get_monotonic_time(esdp);
-		if (current_time >= erts_next_timeout_time(esdp->next_tmo_ref))
-		    erts_bump_timers(esdp->timer_wheel, current_time);
-	    }
-
-	sys_aux_work:
-#ifndef ERTS_SMP
-	    erts_sys_schedule_interrupt(0);
-#endif
-
-	    aux_work = erts_atomic32_read_acqb(&ssi->aux_work);
-	    if (aux_work && !ERTS_SCHEDULER_IS_DIRTY(esdp)) {
-		if (!working)
-		    sched_wall_time_change(esdp, working = 1);
-#ifdef ERTS_SMP
-		if (!thr_prgr_active)
-		    erts_thr_progress_active(esdp, thr_prgr_active = 1);
-#endif
-		aux_work = handle_aux_work(&esdp->aux_work_data, aux_work, 1);
-                ERTS_MSACC_UPDATE_CACHE();
-#ifdef ERTS_SMP
-		if (aux_work && erts_thr_progress_update(esdp))
-		    erts_thr_progress_leader_update(esdp);
-#endif
-	    }
-
-#ifndef ERTS_SMP
-	    if (erts_smp_atomic32_read_dirty(&rq->len) != 0 || rq->misc.start)
-		goto sys_woken;
-#else
-	    flgs = erts_smp_atomic32_read_acqb(&ssi->flags);
-	    if (!(flgs & ERTS_SSI_FLG_WAITING)) {
-		ASSERT(!(flgs & ERTS_SSI_FLG_SLEEPING));
-		goto sys_woken;
-	    }
-
-	    /*
-	     * If we got new I/O tasks we aren't allowed to
-	     * call erl_sys_schedule() until it is handled.
-	     */
-	    if (erts_port_task_have_outstanding_io_tasks()) {
-		clear_sys_scheduling();
-		/*
-		 * Got to check that we still got I/O tasks; otherwise
-		 * we have to continue checking for I/O...
-		 */
-		if (!prepare_for_sys_schedule(0)) {
-		    spincount *= ERTS_SCHED_TSE_SLEEP_SPINCOUNT_FACT;
-		    goto tse_wait;
-		}
-	    }
-#endif
-	}
-
-	erts_smp_runq_lock(rq);
-
-#ifdef ERTS_SMP
-	/*
-	 * If we got new I/O tasks we aren't allowed to
-	 * sleep in erl_sys_schedule().
-	 */
-	if (erts_port_task_have_outstanding_io_tasks()) {
-	    clear_sys_scheduling();
-
-	    /*
-	     * Got to check that we still got I/O tasks; otherwise
-	     * we have to wait in erl_sys_schedule() after all...
-	     */
-	    if (!prepare_for_sys_schedule(0)) {
-		/*
-		 * Not allowed to wait in erl_sys_schedule;
-		 * do tse wait instead...
-		 */
-		sched_change_waiting_sys_to_waiting(esdp->no, rq);
-		erts_smp_runq_unlock(rq);
-		spincount = 0;
-		goto tse_wait;
-	    }
-	}
-#endif
-	if (aux_work) {
-	    erts_smp_runq_unlock(rq);
-	    goto sys_poll_aux_work;
-	}
-#ifdef ERTS_SMP
-	flgs = sched_set_sleeptype(ssi, ERTS_SSI_FLG_POLL_SLEEPING);
-	if (!(flgs & ERTS_SSI_FLG_SLEEPING)) {
-	    if (!(flgs & ERTS_SSI_FLG_WAITING)) {
-		ASSERT(!(flgs & ERTS_SSI_FLG_SLEEPING));
-		goto sys_locked_woken;
-	    }
-	    erts_smp_runq_unlock(rq);
-	    flgs = sched_prep_cont_spin_wait(ssi);
-	    if (!(flgs & ERTS_SSI_FLG_WAITING)) {
-		ASSERT(!(flgs & ERTS_SSI_FLG_SLEEPING));
-		goto sys_woken;
-	    }
-	    ASSERT(!erts_port_task_have_outstanding_io_tasks());
-	    goto sys_poll_aux_work;
-	}
-
-	ASSERT(flgs & ERTS_SSI_FLG_POLL_SLEEPING);
-	ASSERT(flgs & ERTS_SSI_FLG_WAITING);
-#endif
-
-	erts_smp_runq_unlock(rq);
-
-	if (working)
-	    sched_wall_time_change(esdp, working = 0);
-
-#ifdef ERTS_SMP
-	if (thr_prgr_active)
-	    erts_thr_progress_active(esdp, thr_prgr_active = 0);
-#endif
-
-	ASSERT(!erts_port_task_have_outstanding_io_tasks());
-
-	ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_CHECK_IO);
-        LTTNG2(scheduler_poll, esdp->no, 0);
-
-	erl_sys_schedule(0);
-
-	ERTS_MSACC_POP_STATE();
-
-	if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
-	    ErtsMonotonicTime current_time = erts_get_monotonic_time(esdp);
-	    if (current_time >= erts_next_timeout_time(esdp->next_tmo_ref))
-		erts_bump_timers(esdp->timer_wheel, current_time);
-	}
-
-#ifndef ERTS_SMP
-	if (erts_smp_atomic32_read_dirty(&rq->len) == 0 && !rq->misc.start)
-	    goto sys_aux_work;
-    sys_woken:
-#else
-	flgs = sched_prep_cont_spin_wait(ssi);
-	if (flgs & ERTS_SSI_FLG_WAITING)
-	    goto sys_aux_work;
-
-    sys_woken:
-	if (!thr_prgr_active)
-	    erts_thr_progress_active(esdp, thr_prgr_active = 1);
-	erts_smp_runq_lock(rq);
-    sys_locked_woken:
-	if (!thr_prgr_active) {
-	    erts_smp_runq_unlock(rq);
-	    erts_thr_progress_active(esdp, thr_prgr_active = 1);
-	    erts_smp_runq_lock(rq);
-	}
-	clear_sys_scheduling();
-	if (flgs & ~(ERTS_SSI_FLG_SUSPENDED|ERTS_SSI_FLG_MSB_EXEC))
-	    erts_smp_atomic32_read_band_nob(&ssi->flags,
-                                            (ERTS_SSI_FLG_SUSPENDED
-                                             | ERTS_SSI_FLG_MSB_EXEC));
-#endif
-	if (!working)
-	    sched_wall_time_change(esdp, working = 1);
-	sched_active_sys(esdp->no, rq);
+    if (ERTS_SCHEDULER_IS_DIRTY(esdp))
+        dirty_sched_wall_time_change(esdp, working = 1);
+    else if (!thr_prgr_active) {
+        erts_thr_progress_active(esdp, thr_prgr_active = 1);
+        sched_wall_time_change(esdp, 1);
     }
 
+    erts_runq_lock(rq);
+    sched_active(esdp->no, rq);
+
     if (ERTS_SCHEDULER_IS_DIRTY(esdp))
         dirty_active(esdp, 1);
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
 }
 
-#ifdef ERTS_SMP
 
 static ERTS_INLINE erts_aint32_t
 ssi_flags_set_wake(ErtsSchedulerSleepInfo *ssi)
@@ -3802,7 +3445,7 @@ ssi_flags_set_wake(ErtsSchedulerSleepInfo *ssi)
     erts_aint32_t nflgs = 0;
     erts_aint32_t xflgs = ERTS_SSI_FLG_SLEEPING|ERTS_SSI_FLG_WAITING;
     while (1) {
-	oflgs = erts_smp_atomic32_cmpxchg_relb(&ssi->flags, nflgs, xflgs);
+	oflgs = erts_atomic32_cmpxchg_relb(&ssi->flags, nflgs, xflgs);
 	if (oflgs == xflgs)
 	    return oflgs;
 	nflgs = oflgs & (ERTS_SSI_FLG_SUSPENDED|ERTS_SSI_FLG_MSB_EXEC);
@@ -3816,13 +3459,12 @@ ssi_wake(ErtsSchedulerSleepInfo *ssi)
     erts_sched_finish_poke(ssi, ssi_flags_set_wake(ssi));
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 static void
 dcpu_sched_ix_suspend_wake(Uint ix)
 {
     ErtsSchedulerSleepInfo* ssi = ERTS_DIRTY_CPU_SCHED_SLEEP_INFO_IX(ix);
-    erts_smp_atomic32_read_bor_nob(&ssi->flags, ERTS_SSI_FLG_SUSPENDED);
+    erts_atomic32_read_bor_nob(&ssi->flags, ERTS_SSI_FLG_SUSPENDED);
     ssi_wake(ssi);
 }
 
@@ -3830,7 +3472,7 @@ static void
 dio_sched_ix_suspend_wake(Uint ix)
 {
     ErtsSchedulerSleepInfo* ssi = ERTS_DIRTY_IO_SCHED_SLEEP_INFO_IX(ix);
-    erts_smp_atomic32_read_bor_nob(&ssi->flags, ERTS_SSI_FLG_SUSPENDED);
+    erts_atomic32_read_bor_nob(&ssi->flags, ERTS_SSI_FLG_SUSPENDED);
     ssi_wake(ssi);
 }
 
@@ -3848,7 +3490,6 @@ dio_sched_ix_wake(Uint ix)
 }
 #endif
 
-#endif
 
 static void
 wake_scheduler(ErtsRunQueue *rq)
@@ -3861,13 +3502,12 @@ wake_scheduler(ErtsRunQueue *rq)
      * so all code *should* handle this without having
      * the lock on the run queue.
      */
-    ERTS_SMP_LC_ASSERT(!erts_smp_lc_runq_is_locked(rq)
+    ERTS_LC_ASSERT(!erts_lc_runq_is_locked(rq)
 		       || ERTS_RUNQ_IX_IS_DIRTY(rq->ix));
 
     ssi_wake(rq->scheduler->ssi);
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 static void
 wake_dirty_schedulers(ErtsRunQueue *rq, int one)
 {
@@ -3877,10 +3517,10 @@ wake_dirty_schedulers(ErtsRunQueue *rq, int one)
     ASSERT(ERTS_RUNQ_IX_IS_DIRTY(rq->ix));
 
     sl = &rq->sleepers;
-    erts_smp_spin_lock(&sl->lock);
+    erts_spin_lock(&sl->lock);
     ssi = sl->list;
     if (!ssi) {
-	erts_smp_spin_unlock(&sl->lock);
+	erts_spin_unlock(&sl->lock);
 	if (one)
 	    wake_scheduler(rq);
     } else if (one) {
@@ -3894,14 +3534,14 @@ wake_dirty_schedulers(ErtsRunQueue *rq, int one)
 	if (ssi->next)
 	    ssi->next->prev = ssi->prev;
 
-	erts_smp_spin_unlock(&sl->lock);
+	erts_spin_unlock(&sl->lock);
 
 	ERTS_THR_MEMORY_BARRIER;
 	flgs = ssi_flags_set_wake(ssi);
 	erts_sched_finish_poke(ssi, flgs);
     } else {
 	sl->list = NULL;
-	erts_smp_spin_unlock(&sl->lock);
+	erts_spin_unlock(&sl->lock);
 
 	ERTS_THR_MEMORY_BARRIER;
 	do {
@@ -3918,7 +3558,6 @@ wake_dirty_scheduler(ErtsRunQueue *rq)
     wake_dirty_schedulers(rq, 1);
 }
 
-#endif
 
 #define ERTS_NO_USED_RUNQS_SHIFT 16
 #define ERTS_NO_RUNQS_MASK 0xffffU
@@ -3932,13 +3571,13 @@ init_no_runqs(int active, int used)
 {
     erts_aint32_t no_runqs = (erts_aint32_t) (active & ERTS_NO_RUNQS_MASK);
     no_runqs |= (erts_aint32_t) ((used & ERTS_NO_RUNQS_MASK) << ERTS_NO_USED_RUNQS_SHIFT);
-    erts_smp_atomic32_init_nob(&balance_info.no_runqs, no_runqs);
+    erts_atomic32_init_nob(&balance_info.no_runqs, no_runqs);
 }
 
 static ERTS_INLINE void
 get_no_runqs(int *active, int *used)
 {
-    erts_aint32_t no_runqs = erts_smp_atomic32_read_nob(&balance_info.no_runqs);
+    erts_aint32_t no_runqs = erts_atomic32_read_nob(&balance_info.no_runqs);
     if (active)
 	*active = (int) (no_runqs & ERTS_NO_RUNQS_MASK);
     if (used)
@@ -3948,12 +3587,12 @@ get_no_runqs(int *active, int *used)
 static ERTS_INLINE void
 set_no_used_runqs(int used)
 {
-    erts_aint32_t exp = erts_smp_atomic32_read_nob(&balance_info.no_runqs);
+    erts_aint32_t exp = erts_atomic32_read_nob(&balance_info.no_runqs);
     while (1) {
 	erts_aint32_t act, new;
 	new = (used & ERTS_NO_RUNQS_MASK) << ERTS_NO_USED_RUNQS_SHIFT;
 	new |= exp & ERTS_NO_RUNQS_MASK;
-	act = erts_smp_atomic32_cmpxchg_nob(&balance_info.no_runqs, new, exp);
+	act = erts_atomic32_cmpxchg_nob(&balance_info.no_runqs, new, exp);
 	if (act == exp)
 	    break;
 	exp = act;
@@ -3963,14 +3602,14 @@ set_no_used_runqs(int used)
 static ERTS_INLINE void
 set_no_active_runqs(int active)
 {
-    erts_aint32_t exp = erts_smp_atomic32_read_nob(&balance_info.no_runqs);
+    erts_aint32_t exp = erts_atomic32_read_nob(&balance_info.no_runqs);
     while (1) {
 	erts_aint32_t act, new;
 	if ((exp & ERTS_NO_RUNQS_MASK) == active)
 	    break;
 	new = exp & (ERTS_NO_RUNQS_MASK << ERTS_NO_USED_RUNQS_SHIFT);
 	new |= active & ERTS_NO_RUNQS_MASK;
-	act = erts_smp_atomic32_cmpxchg_nob(&balance_info.no_runqs, new, exp);
+	act = erts_atomic32_cmpxchg_nob(&balance_info.no_runqs, new, exp);
 	if (act == exp)
 	    break;
 	exp = act;
@@ -3980,14 +3619,14 @@ set_no_active_runqs(int active)
 static ERTS_INLINE int
 try_inc_no_active_runqs(int active)
 {
-    erts_aint32_t exp = erts_smp_atomic32_read_nob(&balance_info.no_runqs);
+    erts_aint32_t exp = erts_atomic32_read_nob(&balance_info.no_runqs);
     if (((exp >> ERTS_NO_USED_RUNQS_SHIFT) & ERTS_NO_RUNQS_MASK) < active)
 	return 0;
     if ((exp & ERTS_NO_RUNQS_MASK) + 1 == active) {
 	erts_aint32_t new, act;
 	new = exp & (ERTS_NO_RUNQS_MASK << ERTS_NO_USED_RUNQS_SHIFT);
 	new |= active & ERTS_NO_RUNQS_MASK;
-	act = erts_smp_atomic32_cmpxchg_nob(&balance_info.no_runqs, new, exp);
+	act = erts_atomic32_cmpxchg_nob(&balance_info.no_runqs, new, exp);
 	if (act == exp)
 	    return 1;
     }
@@ -4049,25 +3688,20 @@ wake_scheduler_on_empty_runq(ErtsRunQueue *crq)
     }
 }
 
-#endif /* ERTS_SMP */
 
 static ERTS_INLINE void
 smp_notify_inc_runq(ErtsRunQueue *runq)
 {
-#ifdef ERTS_SMP
     if (runq) {
-#ifdef ERTS_DIRTY_SCHEDULERS
 	if (ERTS_RUNQ_IX_IS_DIRTY(runq->ix))
 	    wake_dirty_scheduler(runq);
 	else
-#endif
 	    wake_scheduler(runq);
     }
-#endif
 }
 
 void
-erts_smp_notify_inc_runq(ErtsRunQueue *runq)
+erts_notify_inc_runq(ErtsRunQueue *runq)
 {
     smp_notify_inc_runq(runq);
 }
@@ -4075,16 +3709,12 @@ erts_smp_notify_inc_runq(ErtsRunQueue *runq)
 void
 erts_sched_notify_check_cpu_bind(void)
 {
-#ifdef ERTS_SMP
     int ix;
     for (ix = 0; ix < erts_no_run_queues; ix++) {
 	ErtsRunQueue *rq = ERTS_RUNQ_IX(ix);
 	(void) ERTS_RUNQ_FLGS_SET(rq, ERTS_RUNQ_FLG_CHK_CPU_BIND);
 	wake_scheduler(rq);
     }
-#else
-    erts_sched_check_cpu_bind(erts_get_scheduler_data());
-#endif
 }
 
 
@@ -4093,9 +3723,9 @@ enqueue_process(ErtsRunQueue *runq, int prio, Process *p)
 {
     ErtsRunPrioQueue *rpq;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(runq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(runq));
 
-    erts_smp_inc_runq_len(runq, &runq->procs.prio_info[prio], prio);
+    erts_inc_runq_len(runq, &runq->procs.prio_info[prio], prio);
 
     if (prio == PRIORITY_LOW) {
 	p->schedule_count = RESCHEDULE_LOW;
@@ -4123,7 +3753,7 @@ unqueue_process(ErtsRunQueue *runq,
 		Process *prev_proc,
 		Process *proc)
 {
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(runq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(runq));
 
     if (prev_proc)
 	prev_proc->next = proc->next;
@@ -4135,7 +3765,7 @@ unqueue_process(ErtsRunQueue *runq,
     if (!rpq->first)
 	rpq->last = NULL;
 
-    erts_smp_dec_runq_len(runq, rqi, prio);
+    erts_dec_runq_len(runq, rqi, prio);
 }
 
 
@@ -4148,7 +3778,7 @@ dequeue_process(ErtsRunQueue *runq, int prio_q, erts_aint32_t *statep)
     ErtsRunQueueInfo *rqi;
     Process *p;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(runq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(runq));
 
     ASSERT(PRIORITY_NORMAL == prio_q
 	   || PRIORITY_HIGH == prio_q
@@ -4159,9 +3789,9 @@ dequeue_process(ErtsRunQueue *runq, int prio_q, erts_aint32_t *statep)
     if (!p)
 	return NULL;
 
-    ERTS_SMP_DATA_DEPENDENCY_READ_MEMORY_BARRIER;
+    ERTS_THR_DATA_DEPENDENCY_READ_MEMORY_BARRIER;
 
-    state = erts_smp_atomic32_read_nob(&p->state);
+    state = erts_atomic32_read_nob(&p->state);
     if (statep)
 	*statep = state;
 
@@ -4194,11 +3824,10 @@ check_requeue_process(ErtsRunQueue *rq, int prio_q)
 static ERTS_INLINE void
 free_proxy_proc(Process *proxy)
 {
-    ASSERT(erts_smp_atomic32_read_nob(&proxy->state) & ERTS_PSFLG_PROXY);
+    ASSERT(erts_atomic32_read_nob(&proxy->state) & ERTS_PSFLG_PROXY);
     erts_free(ERTS_ALC_T_PROC, proxy);
 }
 
-#ifdef ERTS_SMP
 
 static ErtsRunQueue *
 check_immigration_need(ErtsRunQueue *c_rq, ErtsMigrationPath *mp, int prio)
@@ -4251,7 +3880,7 @@ static void
 immigrate(ErtsRunQueue *c_rq, ErtsMigrationPath *mp)
 {
     Uint32 iflags, iflag;
-    erts_smp_runq_unlock(c_rq);
+    erts_runq_unlock(c_rq);
 
     ASSERT(erts_thr_progress_is_managed_thread());
 
@@ -4292,13 +3921,13 @@ immigrate(ErtsRunQueue *c_rq, ErtsMigrationPath *mp)
 
 	rq = check_immigration_need(c_rq, mp, prio);
 	if (rq) {
-	    erts_smp_runq_lock(rq);
+	    erts_runq_lock(rq);
 	    if (prio == ERTS_PORT_PRIO_LEVEL) {
 		Port *prt;
 		prt = erts_dequeue_port(rq);
 		if (prt)
 		    RUNQ_SET_RQ(&prt->run_queue, c_rq);
-		erts_smp_runq_unlock(rq);
+		erts_runq_unlock(rq);
 		if (prt) {
 		    /* port might terminate while we have no lock... */
 		    rq = erts_port_runq(prt);
@@ -4310,7 +3939,7 @@ immigrate(ErtsRunQueue *c_rq, ErtsMigrationPath *mp)
 			erts_enqueue_port(c_rq, prt);
 			if (!iflag)
 			    return; /* done */
-			erts_smp_runq_unlock(c_rq);
+			erts_runq_unlock(c_rq);
 		    }
 		}
 	    }
@@ -4324,38 +3953,38 @@ immigrate(ErtsRunQueue *c_rq, ErtsMigrationPath *mp)
 
 		while (proc) {
 		    erts_aint32_t state;
-		    state = erts_smp_atomic32_read_acqb(&proc->state);
+		    state = erts_atomic32_read_acqb(&proc->state);
 		    if (!(ERTS_PSFLG_BOUND & state)
 			&& (prio == (int) ERTS_PSFLGS_GET_PRQ_PRIO(state))) {
 			ErtsRunQueueInfo *rqi = &rq->procs.prio_info[prio];
 			unqueue_process(rq, rpq, rqi, prio, prev_proc, proc);
-			erts_smp_runq_unlock(rq);
+			erts_runq_unlock(rq);
 			RUNQ_SET_RQ(&proc->run_queue, c_rq);
 			rq_locked = 0;
 
-			erts_smp_runq_lock(c_rq);
+			erts_runq_lock(c_rq);
 			enqueue_process(c_rq, prio, proc);
 			if (!iflag)
 			    return; /* done */
-			erts_smp_runq_unlock(c_rq);
+			erts_runq_unlock(c_rq);
 			break;
 		    }
 		    prev_proc = proc;
 		    proc = proc->next;
 		}
 		if (rq_locked)
-		    erts_smp_runq_unlock(rq);
+		    erts_runq_unlock(rq);
 	    }
 	}
     }
 
-    erts_smp_runq_lock(c_rq);
+    erts_runq_lock(c_rq);
 }
 
 static ERTS_INLINE void
 suspend_run_queue(ErtsRunQueue *rq)
 {
-    erts_smp_atomic32_read_bor_nob(&rq->scheduler->ssi->flags,
+    erts_atomic32_read_bor_nob(&rq->scheduler->ssi->flags,
 				   ERTS_SSI_FLG_SUSPENDED);
     (void) ERTS_RUNQ_FLGS_SET(rq, ERTS_RUNQ_FLG_SUSPENDED);
 
@@ -4372,7 +4001,7 @@ resume_run_queue(ErtsRunQueue *rq)
 
     ASSERT(!ERTS_RUNQ_IX_IS_DIRTY(rq->ix));
 
-    erts_smp_runq_lock(rq);
+    erts_runq_lock(rq);
 
     oflgs = ERTS_RUNQ_FLGS_READ_BSET(rq,
 				     (ERTS_RUNQ_FLG_OUT_OF_WORK
@@ -4387,19 +4016,19 @@ resume_run_queue(ErtsRunQueue *rq)
 
 	rq->check_balance_reds = ERTS_RUNQ_CALL_CHECK_BALANCE_REDS;
 	for (pix = 0; pix < ERTS_NO_PROC_PRIO_LEVELS; pix++) {
-	    len = erts_smp_atomic32_read_dirty(&rq->procs.prio_info[pix].len);
+	    len = erts_atomic32_read_dirty(&rq->procs.prio_info[pix].len);
 	    rq->procs.prio_info[pix].max_len = len;
 	    rq->procs.prio_info[pix].reds = 0;
 	}
-	len = erts_smp_atomic32_read_dirty(&rq->ports.info.len);
+	len = erts_atomic32_read_dirty(&rq->ports.info.len);
 	rq->ports.info.max_len = len;
 	rq->ports.info.reds = 0;
-	len = erts_smp_atomic32_read_dirty(&rq->len);
+	len = erts_atomic32_read_dirty(&rq->len);
 	rq->max_len = len;
 
     }
 
-    erts_smp_runq_unlock(rq);
+    erts_runq_unlock(rq);
 
     nrml_sched_ix_resume_wake(rq->ix);
 }
@@ -4414,18 +4043,17 @@ schedule_bound_processes(ErtsRunQueue *rq,
 			 ErtsStuckBoundProcesses *sbpp)
 {
     Process *proc, *next;
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
 
     proc = sbpp->first;
     while (proc) {
-	erts_aint32_t state = erts_smp_atomic32_read_acqb(&proc->state);
+	erts_aint32_t state = erts_atomic32_read_acqb(&proc->state);
 	next = proc->next;
 	enqueue_process(rq, (int) ERTS_PSFLGS_GET_PRQ_PRIO(state), proc);
 	proc = next;
     }
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 static ERTS_INLINE void
 clear_proc_dirty_queue_bit(Process *p, ErtsRunQueue *rq, int prio_bit)
@@ -4445,11 +4073,10 @@ clear_proc_dirty_queue_bit(Process *p, ErtsRunQueue *rq, int prio_bit)
 #else
 	(void)
 #endif
-	erts_smp_atomic32_read_band_mb(&p->dirty_state, ~qb);
+	erts_atomic32_read_band_mb(&p->dirty_state, ~qb);
     ASSERT(old & qb);
 }
 
-#endif /* ERTS_DIRTY_SCHEDULERS */
 
 
 static void
@@ -4461,7 +4088,7 @@ evacuate_run_queue(ErtsRunQueue *rq,
     ErtsMigrationPaths *mps;
     ErtsMigrationPath *mp;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
 
     (void) ERTS_RUNQ_FLGS_UNSET(rq, ERTS_RUNQ_FLG_PROTECTED);
 
@@ -4484,9 +4111,9 @@ evacuate_run_queue(ErtsRunQueue *rq,
 	rq->misc.start = NULL;
 	rq->misc.end = NULL;
         ERTS_RUNQ_FLGS_UNSET_NOB(rq, ERTS_RUNQ_FLG_MISC_OP);
-	erts_smp_runq_unlock(rq);
+	erts_runq_unlock(rq);
 
-	erts_smp_runq_lock(to_rq);
+	erts_runq_lock(to_rq);
 	if (to_rq->misc.end)
 	    to_rq->misc.end->next = start;
 	else
@@ -4496,9 +4123,9 @@ evacuate_run_queue(ErtsRunQueue *rq,
 
 	non_empty_runq(to_rq);
 
-	erts_smp_runq_unlock(to_rq);
+	erts_runq_unlock(to_rq);
 	smp_notify_inc_runq(to_rq);
-	erts_smp_runq_lock(to_rq);
+	erts_runq_lock(to_rq);
     }
 
     if (rq->ports.start) {
@@ -4514,7 +4141,7 @@ evacuate_run_queue(ErtsRunQueue *rq,
 	    ErtsRunQueue *prt_rq;
 	    prt = erts_dequeue_port(rq);
 	    RUNQ_SET_RQ(&prt->run_queue, to_rq);
-	    erts_smp_runq_unlock(rq);
+	    erts_runq_unlock(rq);
 	    /*
 	     * The port might terminate while
 	     * we have no lock on it...
@@ -4526,9 +4153,9 @@ evacuate_run_queue(ErtsRunQueue *rq,
 			     "%s:%d:%s() internal error\n",
 			     __FILE__, __LINE__, __func__);
 		erts_enqueue_port(to_rq, prt);
-		erts_smp_runq_unlock(to_rq);
+		erts_runq_unlock(to_rq);
 	    }
-	    erts_smp_runq_lock(rq);
+	    erts_runq_lock(rq);
 	    prt = rq->ports.start;
 	}
 	smp_notify_inc_runq(to_rq);
@@ -4565,7 +4192,7 @@ evacuate_run_queue(ErtsRunQueue *rq,
 		    free_proxy_proc(proc);
 		    goto handle_next_proc;
 		}
-		real_state =  erts_smp_atomic32_read_acqb(&real_proc->state);
+		real_state =  erts_atomic32_read_acqb(&real_proc->state);
 	    }
 
 	    max_qbit = (state >> ERTS_PSFLGS_IN_PRQ_MASK_OFFSET);
@@ -4591,7 +4218,7 @@ evacuate_run_queue(ErtsRunQueue *rq,
 #else
 			(void)
 #endif
-			erts_smp_atomic32_read_band_mb(&proc->state,
+			erts_atomic32_read_band_mb(&proc->state,
 						       ~clr_bits);
 			ASSERT((old & clr_bits) == clr_bits);
 
@@ -4611,17 +4238,17 @@ evacuate_run_queue(ErtsRunQueue *rq,
 	    }
 	    else {
 		int prio = (int) ERTS_PSFLGS_GET_PRQ_PRIO(state);
-		erts_smp_runq_unlock(rq);
+		erts_runq_unlock(rq);
 
                 to_rq = mp->prio[prio].runq;
 		RUNQ_SET_RQ(&proc->run_queue, to_rq);
 
-		erts_smp_runq_lock(to_rq);
+		erts_runq_lock(to_rq);
 		enqueue_process(to_rq, prio, proc);
-		erts_smp_runq_unlock(to_rq);
+		erts_runq_unlock(to_rq);
 		notify = 1;
 
-		erts_smp_runq_lock(rq);
+		erts_runq_lock(rq);
 	    }
 
 	handle_next_proc:
@@ -4640,13 +4267,13 @@ try_steal_task_from_victim(ErtsRunQueue *rq, int *rq_lockedp, ErtsRunQueue *vrq,
     ErtsRunPrioQueue *rpq;
 
     if (*rq_lockedp) {
-	erts_smp_runq_unlock(rq);
+	erts_runq_unlock(rq);
 	*rq_lockedp = 0;
     }
 
-    ERTS_SMP_LC_ASSERT(!erts_smp_lc_runq_is_locked(rq));
+    ERTS_LC_ASSERT(!erts_lc_runq_is_locked(rq));
 
-    erts_smp_runq_lock(vrq);
+    erts_runq_lock(vrq);
 
     if (ERTS_RUNQ_FLGS_GET_NOB(rq) & ERTS_RUNQ_FLG_HALTING)
 	goto no_procs;
@@ -4682,16 +4309,16 @@ try_steal_task_from_victim(ErtsRunQueue *rq, int *rq_lockedp, ErtsRunQueue *vrq,
 	proc = rpq->first;
 
 	while (proc) {
-	    erts_aint32_t state = erts_smp_atomic32_read_acqb(&proc->state);
+	    erts_aint32_t state = erts_atomic32_read_acqb(&proc->state);
 	    if (!(ERTS_PSFLG_BOUND & state)) {
 		/* Steal process */
 		int prio = (int) ERTS_PSFLGS_GET_PRQ_PRIO(state);
 		ErtsRunQueueInfo *rqi = &vrq->procs.prio_info[prio];
 		unqueue_process(vrq, rpq, rqi, prio, prev_proc, proc);
-		erts_smp_runq_unlock(vrq);
+		erts_runq_unlock(vrq);
 		RUNQ_SET_RQ(&proc->run_queue, rq);
 
-		erts_smp_runq_lock(rq);
+		erts_runq_lock(rq);
 		*rq_lockedp = 1;
 		enqueue_process(rq, prio, proc);
 		return !0;
@@ -4705,7 +4332,7 @@ try_steal_task_from_victim(ErtsRunQueue *rq, int *rq_lockedp, ErtsRunQueue *vrq,
 
 no_procs:
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(vrq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(vrq));
 
     /*
      * Check for a runnable port to steal...
@@ -4715,7 +4342,7 @@ no_procs:
 	ErtsRunQueue *prt_rq;
 	Port *prt = erts_dequeue_port(vrq);
 	RUNQ_SET_RQ(&prt->run_queue, rq);
-	erts_smp_runq_unlock(vrq);
+	erts_runq_unlock(vrq);
 
 	/*
 	 * The port might terminate while
@@ -4736,7 +4363,7 @@ no_procs:
 	}
     }
 
-    erts_smp_runq_unlock(vrq);
+    erts_runq_unlock(vrq);
 
     return 0;
 }
@@ -4768,7 +4395,7 @@ try_steal_task(ErtsRunQueue *rq)
     res = 0;
     rq_locked = 1;
 
-    ERTS_SMP_LC_CHK_RUNQ_LOCK(rq, rq_locked);
+    ERTS_LC_CHK_RUNQ_LOCK(rq, rq_locked);
 
     get_no_runqs(&active_rqs, &blnc_rqs);
 
@@ -4781,7 +4408,7 @@ try_steal_task(ErtsRunQueue *rq)
 	if (active_rqs < blnc_rqs) {
 	    int no = blnc_rqs - active_rqs;
 	    int stop_ix = vix = active_rqs + rq->ix % no;
-	    while (erts_smp_atomic32_read_acqb(&no_empty_run_queues) < blnc_rqs) {
+	    while (erts_atomic32_read_acqb(&no_empty_run_queues) < blnc_rqs) {
 		res = check_possible_steal_victim(rq, &rq_locked, vix);
 		if (res)
 		    goto done;
@@ -4796,7 +4423,7 @@ try_steal_task(ErtsRunQueue *rq)
 	vix = rq->ix;
 
 	/* ... then try to steal a job from another active queue... */
-	while (erts_smp_atomic32_read_acqb(&no_empty_run_queues) < blnc_rqs) {
+	while (erts_atomic32_read_acqb(&no_empty_run_queues) < blnc_rqs) {
 	    vix++;
 	    if (vix >= active_rqs)
 		vix = 0;
@@ -4813,7 +4440,7 @@ try_steal_task(ErtsRunQueue *rq)
  done:
 
     if (!rq_locked)
-	erts_smp_runq_lock(rq);
+	erts_runq_lock(rq);
 
     if (res)
         return res;
@@ -4939,7 +4566,7 @@ alloc_mpaths(void)
 {
     void *block;
     ErtsMigrationPaths *res;
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_mtx_is_locked(&balance_info.update_mtx));
+    ERTS_LC_ASSERT(erts_lc_mtx_is_locked(&balance_info.update_mtx));
 
     res = mpaths.freelist;
     if (res) {
@@ -4962,7 +4589,7 @@ retire_mpaths(ErtsMigrationPaths *mps)
 {
     ErtsThrPrgrVal current;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_mtx_is_locked(&balance_info.update_mtx));
+    ERTS_LC_ASSERT(erts_lc_mtx_is_locked(&balance_info.update_mtx));
 
     current = erts_thr_progress_current();
 
@@ -5008,7 +4635,7 @@ check_balance(ErtsRunQueue *c_rq)
     int sched_util_balancing;
 #endif
 
-    if (erts_smp_atomic32_xchg_nob(&balance_info.checking_balance, 1)) {
+    if (erts_atomic32_xchg_nob(&balance_info.checking_balance, 1)) {
 	c_rq->check_balance_reds = INT_MAX;
 	return;
     }
@@ -5016,15 +4643,15 @@ check_balance(ErtsRunQueue *c_rq)
     get_no_runqs(NULL, &blnc_no_rqs);
     if (blnc_no_rqs == 1) {
 	c_rq->check_balance_reds = INT_MAX;
-	erts_smp_atomic32_set_nob(&balance_info.checking_balance, 0);
+	erts_atomic32_set_nob(&balance_info.checking_balance, 0);
 	return;
     }
 
-    erts_smp_runq_unlock(c_rq);
+    erts_runq_unlock(c_rq);
 
     if (balance_info.halftime) {	
 	balance_info.halftime = 0;
-	erts_smp_atomic32_set_nob(&balance_info.checking_balance, 0);
+	erts_atomic32_set_nob(&balance_info.checking_balance, 0);
 	ERTS_FOREACH_RUNQ(rq,
 	{
 	    if (rq->waiting)
@@ -5034,7 +4661,7 @@ check_balance(ErtsRunQueue *c_rq)
 	    rq->check_balance_reds = ERTS_RUNQ_CALL_CHECK_BALANCE_REDS;
 	});
 
-	erts_smp_runq_lock(c_rq);
+	erts_runq_lock(c_rq);
 	return;
     }
 
@@ -5047,7 +4674,7 @@ check_balance(ErtsRunQueue *c_rq)
      * is manipulated. Such updates of the migration information
      * might clash with balancing.
      */
-    erts_smp_mtx_lock(&balance_info.update_mtx);
+    erts_mtx_lock(&balance_info.update_mtx);
 
     forced = balance_info.forced_check_balance;
     balance_info.forced_check_balance = 0;
@@ -5055,10 +4682,10 @@ check_balance(ErtsRunQueue *c_rq)
     get_no_runqs(&current_active, &blnc_no_rqs);
 
     if (blnc_no_rqs == 1) {
-	erts_smp_mtx_unlock(&balance_info.update_mtx);
-	erts_smp_runq_lock(c_rq);
+	erts_mtx_unlock(&balance_info.update_mtx);
+	erts_runq_lock(c_rq);
 	c_rq->check_balance_reds = INT_MAX;
-	erts_smp_atomic32_set_nob(&balance_info.checking_balance, 0);
+	erts_atomic32_set_nob(&balance_info.checking_balance, 0);
 	return;
     }
 
@@ -5074,7 +4701,7 @@ check_balance(ErtsRunQueue *c_rq)
     /* Read balance information for all run queues */
     for (qix = 0; qix < blnc_no_rqs; qix++) {
 	ErtsRunQueue *rq = ERTS_RUNQ_IX(qix);
-	erts_smp_runq_lock(rq);
+	erts_runq_lock(rq);
 
 	run_queue_info[qix].flags = ERTS_RUNQ_FLGS_GET_NOB(rq);
 	for (pix = 0; pix < ERTS_NO_PROC_PRIO_LEVELS; pix++) {
@@ -5102,7 +4729,7 @@ check_balance(ErtsRunQueue *c_rq)
 	    run_queue_info[qix].sched_util = erts_get_sched_util(rq, 1, 0);
 #endif
 
-	erts_smp_runq_unlock(rq);
+	erts_runq_unlock(rq);
     }
 
     full_scheds = 0;
@@ -5541,7 +5168,7 @@ erts_fprintf(stderr, "--------------------------------\n");
 	Uint32 flags = run_queue_info[qix].flags;
 	ErtsRunQueue *rq = ERTS_RUNQ_IX(qix);
 
-	erts_smp_runq_lock(rq);
+	erts_runq_lock(rq);
 	ASSERT(!(flags & ERTS_RUNQ_FLG_OUT_OF_WORK));
 	if (rq->waiting)
 	    flags |= ERTS_RUNQ_FLG_OUT_OF_WORK;
@@ -5556,27 +5183,27 @@ erts_fprintf(stderr, "--------------------------------\n");
 	rq->out_of_work_count = 0;
 	(void) ERTS_RUNQ_FLGS_READ_BSET(rq, ERTS_RUNQ_FLGS_MIGRATION_INFO, flags);
 
-	rq->max_len = erts_smp_atomic32_read_dirty(&rq->len);
+	rq->max_len = erts_atomic32_read_dirty(&rq->len);
 	for (pix = 0; pix < ERTS_NO_PRIO_LEVELS; pix++) {
 	    ErtsRunQueueInfo *rqi;
 	    rqi = (pix == ERTS_PORT_PRIO_LEVEL
 		   ? &rq->ports.info
 		   : &rq->procs.prio_info[pix]);
-	    erts_smp_reset_max_len(rq, rqi);
+	    erts_reset_max_len(rq, rqi);
 	    rqi->reds = 0;
 	}
 
 	rq->check_balance_reds = ERTS_RUNQ_CALL_CHECK_BALANCE_REDS;
-	erts_smp_runq_unlock(rq);
+	erts_runq_unlock(rq);
     }
 
-    erts_smp_atomic32_set_nob(&balance_info.checking_balance, 0);
+    erts_atomic32_set_nob(&balance_info.checking_balance, 0);
 
     balance_info.n++;
     retire_mpaths(old_mpaths);
-    erts_smp_mtx_unlock(&balance_info.update_mtx);
+    erts_mtx_unlock(&balance_info.update_mtx);
 
-    erts_smp_runq_lock(c_rq);
+    erts_runq_lock(c_rq);
 }
 
 static void
@@ -5584,7 +5211,7 @@ change_no_used_runqs(int used)
 {
     ErtsMigrationPaths *new_mpaths, *old_mpaths;
     int qix;
-    erts_smp_mtx_lock(&balance_info.update_mtx);
+    erts_mtx_lock(&balance_info.update_mtx);
     set_no_used_runqs(used);
 
     old_mpaths = erts_get_migration_paths_managed();
@@ -5631,28 +5258,23 @@ change_no_used_runqs(int used)
     /* Make sure that we balance soon... */
     balance_info.forced_check_balance = 1;
 
-    erts_smp_mtx_unlock(&balance_info.update_mtx);
+    erts_mtx_unlock(&balance_info.update_mtx);
 
-    erts_smp_runq_lock(ERTS_RUNQ_IX(0));
+    erts_runq_lock(ERTS_RUNQ_IX(0));
     ERTS_RUNQ_IX(0)->check_balance_reds = 0;
-    erts_smp_runq_unlock(ERTS_RUNQ_IX(0));
+    erts_runq_unlock(ERTS_RUNQ_IX(0));
 }
 
 
-#endif /* #ifdef ERTS_SMP */
 
 Uint
 erts_debug_nbalance(void)
 {
-#ifdef ERTS_SMP
     Uint n;
-    erts_smp_mtx_lock(&balance_info.update_mtx);
+    erts_mtx_lock(&balance_info.update_mtx);
     n = balance_info.n;
-    erts_smp_mtx_unlock(&balance_info.update_mtx);
+    erts_mtx_unlock(&balance_info.update_mtx);
     return n;
-#else
-    return 0;
-#endif
 }
 
 /* Wakeup other schedulers */
@@ -5698,7 +5320,6 @@ typedef enum {
 #define ERTS_WAKEUP_OTHER_DEC_LEGACY 10
 #define ERTS_WAKEUP_OTHER_FIXED_INC_LEGACY (CONTEXT_REDS/10)
 
-#ifdef ERTS_SMP
 
 static struct {
     ErtsSchedWakeupOtherThreshold threshold;
@@ -5714,7 +5335,7 @@ wakeup_other_check(ErtsRunQueue *rq, Uint32 flags)
 {
     int wo_reds = rq->wakeup_other_reds;
     if (wo_reds) {
-	int left_len = erts_smp_atomic32_read_dirty(&rq->len) - 1;
+	int left_len = erts_atomic32_read_dirty(&rq->len) - 1;
 	if (left_len < 1) {
 	    int wo_reduce = wo_reds << wakeup_other.dec_shift;
 	    wo_reduce &= wakeup_other.dec_mask;
@@ -5726,16 +5347,14 @@ wakeup_other_check(ErtsRunQueue *rq, Uint32 flags)
 	    rq->wakeup_other += (left_len*wo_reds
 				 + ERTS_WAKEUP_OTHER_FIXED_INC);
 	    if (rq->wakeup_other > wakeup_other.limit) {
-#ifdef ERTS_DIRTY_SCHEDULERS
 		if (ERTS_RUNQ_IX_IS_DIRTY(rq->ix)) {
 		    if (rq->waiting) {
 			wake_dirty_scheduler(rq);
 		    }
 		} else
-#endif
 		{
 		    int empty_rqs =
-			erts_smp_atomic32_read_acqb(&no_empty_run_queues);
+			erts_atomic32_read_acqb(&no_empty_run_queues);
 		    if (flags & ERTS_RUNQ_FLG_PROTECTED)
 			(void) ERTS_RUNQ_FLGS_UNSET(rq, ERTS_RUNQ_FLG_PROTECTED);
 		    if (empty_rqs != 0)
@@ -5787,7 +5406,7 @@ wakeup_other_check_legacy(ErtsRunQueue *rq, Uint32 flags)
 {
     int wo_reds = rq->wakeup_other_reds;
     if (wo_reds) {
-	erts_aint32_t len = erts_smp_atomic32_read_dirty(&rq->len);
+	erts_aint32_t len = erts_atomic32_read_dirty(&rq->len);
 	if (len < 2) {
 	    rq->wakeup_other -= ERTS_WAKEUP_OTHER_DEC_LEGACY*wo_reds;
 	    if (rq->wakeup_other < 0)
@@ -5798,7 +5417,7 @@ wakeup_other_check_legacy(ErtsRunQueue *rq, Uint32 flags)
 	else {
 	    if (flags & ERTS_RUNQ_FLG_PROTECTED)
 		(void) ERTS_RUNQ_FLGS_UNSET(rq, ERTS_RUNQ_FLG_PROTECTED);
-	    if (erts_smp_atomic32_read_acqb(&no_empty_run_queues) != 0) {
+	    if (erts_atomic32_read_acqb(&no_empty_run_queues) != 0) {
 		wake_scheduler_on_empty_runq(rq);
 		rq->wakeup_other = 0;
 	    }
@@ -5849,7 +5468,7 @@ static int
 no_runqs_to_supervise(void)
 {
     int used;
-    erts_aint32_t nerq = erts_smp_atomic32_read_acqb(&no_empty_run_queues);
+    erts_aint32_t nerq = erts_atomic32_read_acqb(&no_empty_run_queues);
     if (nerq <= 0)
 	return 0;
     get_no_runqs(NULL, &used);
@@ -5882,26 +5501,23 @@ runq_supervisor(void *unused)
 	for (ix = 0; ix < no_rqs; ix++) {
 	    ErtsRunQueue *rq = ERTS_RUNQ_IX(ix);
 	    if (ERTS_RUNQ_FLGS_GET(rq) & ERTS_RUNQ_FLG_NONEMPTY) {
-		erts_smp_runq_lock(rq);
-		if (erts_smp_atomic32_read_dirty(&rq->len) != 0)
+		erts_runq_lock(rq);
+		if (erts_atomic32_read_dirty(&rq->len) != 0)
 		    wake_scheduler_on_empty_runq(rq); /* forced wakeup... */
-		erts_smp_runq_unlock(rq);
+		erts_runq_unlock(rq);
 	    }
 	}
     }
     return NULL;
 }
 
-#endif
 
 void
 erts_early_init_scheduling(int no_schedulers)
 {
     aux_work_timeout_early_init(no_schedulers);
-#ifdef ERTS_SMP
     wakeup_other.threshold = ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_MEDIUM;
     wakeup_other.type = ERTS_SCHED_WAKEUP_OTHER_TYPE_DEFAULT;
-#endif
     sched_busy_wait.sys_schedule = ERTS_SCHED_SYS_SLEEP_SPINCOUNT_MEDIUM;
     sched_busy_wait.tse = (ERTS_SCHED_SYS_SLEEP_SPINCOUNT_MEDIUM
 			   * ERTS_SCHED_TSE_SLEEP_SPINCOUNT_FACT);
@@ -5912,7 +5528,6 @@ erts_early_init_scheduling(int no_schedulers)
 int
 erts_sched_set_wakeup_other_thresold(char *str)
 {
-#ifdef ERTS_SMP
     ErtsSchedWakeupOtherThreshold threshold;
     if (sys_strcmp(str, "very_high") == 0)
 	threshold = ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_VERY_HIGH;
@@ -5929,20 +5544,11 @@ erts_sched_set_wakeup_other_thresold(char *str)
     wakeup_other.threshold = threshold;
     set_wakeup_other_data();
     return 0;
-#else
-    if (sys_strcmp(str, "very_high") == 0 || sys_strcmp(str, "high") == 0 ||
-	sys_strcmp(str, "medium") == 0 || sys_strcmp(str, "low") == 0 ||
-	sys_strcmp(str, "very_low") == 0) {
-	return 0;
-    } 
-    return EINVAL;
-#endif
 }
 
 int
 erts_sched_set_wakeup_other_type(char *str)
 {
-#ifdef ERTS_SMP
     ErtsSchedWakeupOtherType type;
     if (sys_strcmp(str, "default") == 0)
 	type = ERTS_SCHED_WAKEUP_OTHER_TYPE_DEFAULT;
@@ -5952,12 +5558,6 @@ erts_sched_set_wakeup_other_type(char *str)
 	return EINVAL;
     wakeup_other.type = type;
     return 0;
-#else
-    if (sys_strcmp(str, "default") == 0 || sys_strcmp(str, "legacy") == 0) {
-	return 0;
-    } 
-    return EINVAL;
-#endif
 }
 
 int
@@ -6028,7 +5628,6 @@ init_aux_work_data(ErtsAuxWorkData *awdp, ErtsSchedulerData *esdp, char *dawwp)
         case ERTS_SCHED_NORMAL:
             id = (int) esdp->no;
             break;
-#ifdef ERTS_DIRTY_SCHEDULERS
         case ERTS_SCHED_DIRTY_CPU:
             id = (int) erts_no_schedulers;
             id += (int) esdp->dirty_no;
@@ -6038,7 +5637,6 @@ init_aux_work_data(ErtsAuxWorkData *awdp, ErtsSchedulerData *esdp, char *dawwp)
             id += (int) erts_no_dirty_cpu_schedulers;
             id += (int) esdp->dirty_no;
             break;
-#endif
         default:
             ERTS_INTERNAL_ERROR("Invalid scheduler type");
             break;
@@ -6048,7 +5646,6 @@ init_aux_work_data(ErtsAuxWorkData *awdp, ErtsSchedulerData *esdp, char *dawwp)
     awdp->sched_id = id;
     awdp->esdp = esdp;
     awdp->ssi = esdp ? esdp->ssi : NULL;
-#ifdef ERTS_SMP
     awdp->latest_wakeup = ERTS_THR_PRGR_VAL_FIRST;
     awdp->misc.thr_prgr = ERTS_THR_PRGR_VAL_WAITING;
     awdp->dd.thr_prgr = ERTS_THR_PRGR_VAL_WAITING;
@@ -6057,15 +5654,9 @@ init_aux_work_data(ErtsAuxWorkData *awdp, ErtsSchedulerData *esdp, char *dawwp)
     awdp->later_op.size = 0;
     awdp->later_op.first = NULL;
     awdp->later_op.last = NULL;
-#endif
-#ifdef ERTS_USE_ASYNC_READY_Q
-#ifdef ERTS_SMP
     awdp->async_ready.need_thr_prgr = 0;
     awdp->async_ready.thr_prgr = ERTS_THR_PRGR_VAL_WAITING;
-#endif
     awdp->async_ready.queue = NULL;
-#endif
-#ifdef ERTS_SMP
     awdp->delayed_wakeup.next = ERTS_DELAYED_WAKEUP_INFINITY;
     if (!dawwp) {
 	awdp->delayed_wakeup.job = NULL;
@@ -6081,7 +5672,6 @@ init_aux_work_data(ErtsAuxWorkData *awdp, ErtsSchedulerData *esdp, char *dawwp)
 	for (i = 0; i <= erts_no_schedulers; i++)
 	    awdp->delayed_wakeup.sched2jix[i] = -1;
     }
-#endif
     awdp->debug.wait_completed.flags = 0;
     awdp->debug.wait_completed.callback = NULL;
     awdp->debug.wait_completed.arg = NULL;
@@ -6096,11 +5686,9 @@ init_scheduler_data(ErtsSchedulerData* esdp, int num,
                     Uint64 time_stamp)
 {
     esdp->timer_wheel = NULL;
-#ifdef ERTS_SMP
     erts_bits_init_state(&esdp->erl_bits_state);
     esdp->match_pseudo_process = NULL;
     esdp->free_process = NULL;
-#endif
     esdp->x_reg_array =
 	erts_alloc_permanent_cache_aligned(ERTS_ALC_T_BEAM_REGISTER,
 					   ERTS_X_REGS_ALLOCATED *
@@ -6108,7 +5696,6 @@ init_scheduler_data(ErtsSchedulerData* esdp, int num,
     esdp->f_reg_array =
 	erts_alloc_permanent_cache_aligned(ERTS_ALC_T_BEAM_REGISTER,
 					   MAX_REG * sizeof(FloatDef));
-#ifdef ERTS_DIRTY_SCHEDULERS
     esdp->run_queue = runq;
     if (ERTS_RUNQ_IX_IS_DIRTY(runq->ix)) {
 	esdp->no = 0;
@@ -6136,19 +5723,14 @@ init_scheduler_data(ErtsSchedulerData* esdp, int num,
     esdp->dirty_shadow_process = shadow_proc;
     if (shadow_proc) {
 	erts_init_empty_process(shadow_proc);
-	erts_smp_atomic32_init_nob(&shadow_proc->state,
+	erts_atomic32_init_nob(&shadow_proc->state,
 				   (ERTS_PSFLG_ACTIVE
 				    | ERTS_PSFLG_DIRTY_RUNNING
 				    | ERTS_PSFLG_PROXY));
 	shadow_proc->static_flags = ERTS_STC_FLG_SHADOW_PROC;
     }
-#else
-    runq->scheduler = esdp;
-    esdp->run_queue = runq;
-    esdp->no = (Uint) num;
-    esdp->type = ERTS_SCHED_NORMAL;
-#endif
 
+    ssi->esdp = esdp;
     esdp->ssi = ssi;
     esdp->current_process = NULL;
     esdp->current_port = NULL;
@@ -6169,9 +5751,7 @@ init_scheduler_data(ErtsSchedulerData* esdp, int num,
 
     if (daww_ptr) {
 	init_aux_work_data(&esdp->aux_work_data, esdp, *daww_ptr);
-#ifdef ERTS_SMP
 	*daww_ptr += daww_sz;
-#endif
     }
 
     esdp->reductions = 0;
@@ -6181,27 +5761,21 @@ init_scheduler_data(ErtsSchedulerData* esdp, int num,
 }
 
 void
-erts_init_scheduling(int no_schedulers, int no_schedulers_online
-#ifdef ERTS_DIRTY_SCHEDULERS
-		     , int no_dirty_cpu_schedulers, int no_dirty_cpu_schedulers_online,
+erts_init_scheduling(int no_schedulers, int no_schedulers_online, int no_poll_threads,
+		     int no_dirty_cpu_schedulers, int no_dirty_cpu_schedulers_online,
 		     int no_dirty_io_schedulers
-#endif
 		     )
 {
     int ix, n, no_ssi, tot_rqs;
     char *daww_ptr;
     size_t daww_sz;
     size_t size_runqs;
-#ifdef ERTS_SMP
     erts_aint32_t set_schdlr_sspnd_change_flags;
-#endif
 
     init_misc_op_list_alloc();
     init_proc_sys_task_queues_alloc();
 
-#ifdef ERTS_SMP
     set_wakeup_other_data();
-#endif
 
 #if ERTS_HAVE_SCHED_UTIL_BALANCING_SUPPORT
     if (erts_sched_balance_util)
@@ -6211,12 +5785,11 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
     ASSERT(no_schedulers_online <= no_schedulers);
     ASSERT(no_schedulers_online >= 1);
     ASSERT(no_schedulers >= 1);
-#ifdef ERTS_DIRTY_SCHEDULERS
     ASSERT(no_dirty_cpu_schedulers <= no_schedulers);
     ASSERT(no_dirty_cpu_schedulers >= 1);
     ASSERT(no_dirty_cpu_schedulers_online <= no_schedulers_online);
     ASSERT(no_dirty_cpu_schedulers_online >= 1);
-#endif
+    ASSERT(erts_no_poll_threads == no_poll_threads);
 
     /* Create and initialize run queues */
 
@@ -6225,9 +5798,7 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
     size_runqs = sizeof(ErtsAlignedRunQueue) * tot_rqs;
     erts_aligned_run_queues =
 	erts_alloc_permanent_cache_aligned(ERTS_ALC_T_RUNQS, size_runqs);
-#ifdef ERTS_SMP
-    erts_smp_atomic32_init_nob(&no_empty_run_queues, 0);
-#endif
+    erts_atomic32_init_nob(&no_empty_run_queues, 0);
 
     erts_no_run_queues = n;
 
@@ -6241,20 +5812,16 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
 	 * id if the esdp->no <-> ix+1 mapping change.
 	 */
 
-	erts_smp_mtx_init(&rq->mtx, "run_queue", make_small(ix + 1),
+	erts_mtx_init(&rq->mtx, "run_queue", make_small(ix + 1),
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_SCHEDULER);
-	erts_smp_cnd_init(&rq->cnd);
+	erts_cnd_init(&rq->cnd);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
-#ifdef ERTS_SMP
         if (ERTS_RUNQ_IX_IS_DIRTY(ix)) {
-            erts_smp_spinlock_init(&rq->sleepers.lock, "dirty_run_queue_sleep_list",
+            erts_spinlock_init(&rq->sleepers.lock, "dirty_run_queue_sleep_list",
                 make_small(ix + 1),
                 ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_SCHEDULER);
         }
 	rq->sleepers.list = NULL;
-#endif
-#endif
 
 	rq->waiting = 0;
 	rq->woken = 0;
@@ -6267,7 +5834,7 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
 	}
 	rq->out_of_work_count = 0;
 	rq->max_len = 0;
-	erts_smp_atomic32_set_nob(&rq->len, 0);
+	erts_atomic32_set_nob(&rq->len, 0);
 	rq->wakeup_other = 0;
 	rq->wakeup_other_reds = 0;
 
@@ -6276,7 +5843,7 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
 	rq->procs.reductions = 0;
 
 	for (pix = 0; pix < ERTS_NO_PROC_PRIO_LEVELS; pix++) {
-	    erts_smp_atomic32_init_nob(&rq->procs.prio_info[pix].len, 0);
+	    erts_atomic32_init_nob(&rq->procs.prio_info[pix].len, 0);
 	    rq->procs.prio_info[pix].max_len = 0;
 	    rq->procs.prio_info[pix].reds = 0;
 	    if (pix < ERTS_NO_PROC_PRIO_LEVELS - 1) {
@@ -6288,7 +5855,7 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
 	rq->misc.start = NULL;
 	rq->misc.end = NULL;
 
-	erts_smp_atomic32_init_nob(&rq->ports.info.len, 0);
+	erts_atomic32_init_nob(&rq->ports.info.len, 0);
 	rq->ports.info.max_len = 0;
 	rq->ports.info.reds = 0;
 	rq->ports.start = NULL;
@@ -6300,7 +5867,6 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
 
     }
 
-#ifdef ERTS_SMP
 
     if (erts_no_run_queues != 1) {
 	run_queue_info = erts_alloc(ERTS_ALC_T_RUNQ_BLNS,
@@ -6311,52 +5877,42 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
 					* erts_no_run_queues));
     }
 
-#endif
 
     n = (int) no_schedulers;
     erts_no_schedulers = n;
     erts_no_total_schedulers = n;
-#ifdef ERTS_DIRTY_SCHEDULERS
     erts_no_dirty_cpu_schedulers = no_dirty_cpu_schedulers;
     erts_no_total_schedulers += no_dirty_cpu_schedulers;
     erts_no_dirty_io_schedulers = no_dirty_io_schedulers;
     erts_no_total_schedulers += no_dirty_io_schedulers;
-#endif
 
     /* Create and initialize scheduler sleep info */
-#ifdef ERTS_SMP
-    no_ssi = n+1;
-#else
-    no_ssi = 1;
-#endif
+    no_ssi = n + 1 /* aux thread */;
     aligned_sched_sleep_info =
 	erts_alloc_permanent_cache_aligned(
 	    ERTS_ALC_T_SCHDLR_SLP_INFO,
 	    no_ssi*sizeof(ErtsAlignedSchedulerSleepInfo));
     for (ix = 0; ix < no_ssi; ix++) {
 	ErtsSchedulerSleepInfo *ssi = &aligned_sched_sleep_info[ix].ssi;
-#ifdef ERTS_SMP
 #if 0 /* no need to initialize these... */
 	ssi->next = NULL;
 	ssi->prev = NULL;
 #endif
-	erts_smp_atomic32_init_nob(&ssi->flags, 0);
+        ssi->esdp = NULL;
+	erts_atomic32_init_nob(&ssi->flags, 0);
 	ssi->event = NULL; /* initialized in sched_thread_func */
-#endif
 	erts_atomic32_init_nob(&ssi->aux_work, 0);
     }
 
-#ifdef ERTS_SMP
-    aligned_sched_sleep_info++;
+    aligned_sched_sleep_info += 1 /* aux thread */;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     aligned_dirty_cpu_sched_sleep_info =
 	erts_alloc_permanent_cache_aligned(
 	    ERTS_ALC_T_SCHDLR_SLP_INFO,
 	    no_dirty_cpu_schedulers*sizeof(ErtsAlignedSchedulerSleepInfo));
     for (ix = 0; ix < no_dirty_cpu_schedulers; ix++) {
 	ErtsSchedulerSleepInfo *ssi = &aligned_dirty_cpu_sched_sleep_info[ix].ssi;
-	erts_smp_atomic32_init_nob(&ssi->flags, 0);
+	erts_atomic32_init_nob(&ssi->flags, 0);
 	ssi->event = NULL; /* initialized in sched_dirty_cpu_thread_func */
 	erts_atomic32_init_nob(&ssi->aux_work, 0);
     }
@@ -6366,24 +5922,29 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
 	    no_dirty_io_schedulers*sizeof(ErtsAlignedSchedulerSleepInfo));
     for (ix = 0; ix < no_dirty_io_schedulers; ix++) {
 	ErtsSchedulerSleepInfo *ssi = &aligned_dirty_io_sched_sleep_info[ix].ssi;
-	erts_smp_atomic32_init_nob(&ssi->flags, 0);
+	erts_atomic32_init_nob(&ssi->flags, 0);
 	ssi->event = NULL; /* initialized in sched_dirty_io_thread_func */
 	erts_atomic32_init_nob(&ssi->aux_work, 0);
     }
-#endif
-#endif
+
+    aligned_poll_thread_sleep_info =
+        erts_alloc_permanent_cache_aligned(
+	    ERTS_ALC_T_SCHDLR_SLP_INFO,
+	    no_poll_threads*sizeof(ErtsAlignedSchedulerSleepInfo));
+    for (ix = 0; ix < no_poll_threads; ix++) {
+        ErtsSchedulerSleepInfo *ssi = &aligned_poll_thread_sleep_info[ix].ssi;
+        ssi->esdp = NULL;
+	erts_atomic32_init_nob(&ssi->flags, 0);
+	ssi->event = NULL; /* initialized in poll_thread */
+	erts_atomic32_init_nob(&ssi->aux_work, 0);
+    }
 
     /* Create and initialize scheduler specific data */
 
-#ifdef ERTS_SMP
     daww_sz = ERTS_ALC_CACHE_LINE_ALIGN_SIZE((sizeof(ErtsDelayedAuxWorkWakeupJob)
 					      + sizeof(int))*(n+1));
     daww_ptr = erts_alloc_permanent_cache_aligned(ERTS_ALC_T_SCHDLR_DATA,
 						  daww_sz*n);
-#else
-    daww_sz = 0;
-    daww_ptr = NULL;
-#endif
 
     erts_aligned_scheduler_data = 
 	erts_alloc_permanent_cache_aligned(ERTS_ALC_T_SCHDLR_DATA,
@@ -6396,7 +5957,6 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
 			    NULL, 0);
     }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     {
         Uint64 ts = sched_wall_time_ts();
 	int dirty_scheds = no_dirty_cpu_schedulers + no_dirty_io_schedulers;
@@ -6427,7 +5987,6 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
 				&adsp[adspix++].dsp, ts);
 	}
     }
-#endif
 
     init_misc_aux_work();
     init_swtreq_alloc();
@@ -6436,20 +5995,22 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
     erts_atomic32_init_nob(&debug_wait_completed_count, 0); /* debug only */
     debug_wait_completed_flags = 0;
 
-#ifdef ERTS_SMP
-
     aux_thread_aux_work_data =
 	erts_alloc_permanent_cache_aligned(ERTS_ALC_T_SCHDLR_DATA,
 					   sizeof(ErtsAuxWorkData));
 
+    poll_thread_aux_work_data =
+	erts_alloc_permanent_cache_aligned(ERTS_ALC_T_SCHDLR_DATA,
+					   no_poll_threads * sizeof(ErtsAuxWorkData));
+
     init_no_runqs(no_schedulers_online, no_schedulers_online);
     balance_info.last_active_runqs = no_schedulers;
-    erts_smp_mtx_init(&balance_info.update_mtx, "migration_info_update", NIL,
+    erts_mtx_init(&balance_info.update_mtx, "migration_info_update", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_SCHEDULER);
     balance_info.forced_check_balance = 0;
     balance_info.halftime = 1;
     balance_info.full_reds_history_index = 0;
-    erts_smp_atomic32_init_nob(&balance_info.checking_balance, 0);
+    erts_atomic32_init_nob(&balance_info.checking_balance, 0);
     balance_info.prev_rise.active_runqs = 0;
     balance_info.prev_rise.max_len = 0;
     balance_info.prev_rise.reds = 0;
@@ -6480,7 +6041,6 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
 	    suspend_run_queue(ERTS_RUNQ_IX(ix));
     }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
     schdlr_sspnd_set_nscheds(&schdlr_sspnd.online,
 			     ERTS_SCHED_DIRTY_CPU,
@@ -6497,7 +6057,7 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
 	set_schdlr_sspnd_change_flags |= ERTS_SCHDLR_SSPND_CHNG_DCPU_ONLN;
 	for (ix = no_dirty_cpu_schedulers_online; ix < no_dirty_cpu_schedulers; ix++) {
 	    ErtsSchedulerData* esdp = ERTS_DIRTY_CPU_SCHEDULER_IX(ix);
-	    erts_smp_atomic32_read_bor_nob(&esdp->ssi->flags, ERTS_SSI_FLG_SUSPENDED);
+	    erts_atomic32_read_bor_nob(&esdp->ssi->flags, ERTS_SSI_FLG_SUSPENDED);
 	}
     }
 
@@ -6511,54 +6071,26 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online
 			     ERTS_SCHED_DIRTY_IO,
 			     no_dirty_io_schedulers);
 
-    erts_smp_atomic32_init_nob(&dirty_count.cpu.active,
+    erts_atomic32_init_nob(&dirty_count.cpu.active,
                                (erts_aint32_t) no_dirty_cpu_schedulers);
-    erts_smp_atomic32_init_nob(&dirty_count.io.active,
+    erts_atomic32_init_nob(&dirty_count.io.active,
                                (erts_aint32_t) no_dirty_io_schedulers);
 
-#endif
 
     if (set_schdlr_sspnd_change_flags)
-	erts_smp_atomic32_set_nob(&schdlr_sspnd.changing,
+	erts_atomic32_set_nob(&schdlr_sspnd.changing,
 				  set_schdlr_sspnd_change_flags);
 
-    erts_smp_atomic32_init_nob(&doing_sys_schedule, 0);
-
     init_misc_aux_work();
 
-#else /* !ERTS_SMP */
-    {
-	ErtsSchedulerData *esdp;
-	esdp = ERTS_SCHEDULER_IX(0);
-	erts_scheduler_data = esdp;
-#ifdef USE_THREADS
-	erts_tsd_set(sched_data_key, (void *) esdp);
-#endif
-    }
-    erts_no_dirty_cpu_schedulers = 0;
-    erts_no_dirty_io_schedulers = 0;
-#endif
-
-    erts_smp_atomic32_init_nob(&function_calls, 0);
 
     /* init port tasks */
     erts_port_task_init();
 
-#ifndef ERTS_SMP
-#ifdef ERTS_DO_VERIFY_UNUSED_TEMP_ALLOC
-    erts_scheduler_data->verify_unused_temp_alloc
-	= erts_alloc_get_verify_unused_temp_alloc(
-	    &erts_scheduler_data->verify_unused_temp_alloc_data);
-    ERTS_VERIFY_UNUSED_TEMP_ALLOC(NULL);
-#endif
-#endif
 
-    erts_smp_atomic32_init_relb(&erts_halt_progress, -1);
+    erts_atomic32_init_relb(&erts_halt_progress, -1);
     erts_halt_code = 0;
 
-#if !defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
-    erts_lc_set_thread_name("scheduler 1");
-#endif
 
 }
 
@@ -6571,7 +6103,6 @@ erts_schedid2runq(Uint id)
     return ERTS_RUNQ_IX(ix);
 }
 
-#ifdef USE_THREADS
 
 ErtsSchedulerData *
 erts_get_scheduler_data(void)
@@ -6579,16 +6110,13 @@ erts_get_scheduler_data(void)
     return (ErtsSchedulerData *) erts_tsd_get(sched_data_key);
 }
 
-#endif
 
 static Process *
 make_proxy_proc(Process *prev_proxy, Process *proc, erts_aint32_t prio)
 {
     erts_aint32_t state;
     Process *proxy;
-#ifdef ERTS_SMP
     ErtsRunQueue *rq = RUNQ_READ_RQ(&proc->run_queue);
-#endif
 
     state = (ERTS_PSFLG_PROXY
 	     | ERTS_PSFLG_IN_RUNQ
@@ -6599,11 +6127,9 @@ make_proxy_proc(Process *prev_proxy, Process *proc, erts_aint32_t prio)
 
     if (prev_proxy) {
 	proxy = prev_proxy;
-	ASSERT(erts_smp_atomic32_read_nob(&proxy->state) & ERTS_PSFLG_PROXY);
-	erts_smp_atomic32_set_nob(&proxy->state, state);
-#ifdef ERTS_SMP
+	ASSERT(erts_atomic32_read_nob(&proxy->state) & ERTS_PSFLG_PROXY);
+	erts_atomic32_set_nob(&proxy->state, state);
 	RUNQ_SET_RQ(&proc->run_queue, rq);
-#endif
     }
     else {
 	proxy = erts_alloc(ERTS_ALC_T_PROC, sizeof(Process));
@@ -6615,11 +6141,9 @@ make_proxy_proc(Process *prev_proxy, Process *proc, erts_aint32_t prio)
 		ui32[i] = (Uint32) 0xdeadbeef;
 	}
 #endif
-	erts_smp_atomic32_init_nob(&proxy->state, state);
-#ifdef ERTS_SMP
-	erts_smp_atomic_init_nob(&proxy->run_queue,
-				 erts_smp_atomic_read_nob(&proc->run_queue));
-#endif
+	erts_atomic32_init_nob(&proxy->state, state);
+	erts_atomic_init_nob(&proxy->run_queue,
+				 erts_atomic_read_nob(&proc->run_queue));
     }
 
     proxy->common.id = proc->common.id;
@@ -6632,7 +6156,6 @@ make_proxy_proc(Process *prev_proxy, Process *proc, erts_aint32_t prio)
 #define ERTS_ENQUEUE_DIRTY_CPU_QUEUE 2
 #define ERTS_ENQUEUE_DIRTY_IO_QUEUE 3
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 static int
 check_dirty_enqueue_in_prio_queue(Process *c_p,
@@ -6663,7 +6186,7 @@ check_dirty_enqueue_in_prio_queue(Process *c_p,
     if ((*newp) & ERTS_PSFLG_ACTIVE_SYS)
 	return ERTS_ENQUEUE_NORMAL_QUEUE;
 
-    dact = erts_smp_atomic32_read_mb(&c_p->dirty_state);
+    dact = erts_atomic32_read_mb(&c_p->dirty_state);
     if (actual & (ERTS_PSFLG_DIRTY_ACTIVE_SYS
 		  | ERTS_PSFLG_DIRTY_CPU_PROC)) {
 	max_qbit = ((dact >> ERTS_PDSFLGS_IN_CPU_PRQ_MASK_OFFSET)
@@ -6708,7 +6231,7 @@ fin_dirty_enq_s_change(Process *p,
     erts_aint32_t qbit = 1 << enq_prio;
     qbit <<= qmask_offset;
 
-    if (qbit & erts_smp_atomic32_read_bor_mb(&p->dirty_state, qbit)) {
+    if (qbit & erts_atomic32_read_bor_mb(&p->dirty_state, qbit)) {
 	/* Already enqueue by someone else... */
 	if (pstruct_reserved) {
 	    /* We reserved process struct for enqueue; clear it... */
@@ -6717,7 +6240,7 @@ fin_dirty_enq_s_change(Process *p,
 #else
 		(void)
 #endif
-		erts_smp_atomic32_read_band_nob(&p->state, ~ERTS_PSFLG_IN_RUNQ);
+		erts_atomic32_read_band_nob(&p->state, ~ERTS_PSFLG_IN_RUNQ);
 	    ASSERT(old & ERTS_PSFLG_IN_RUNQ);
 	}
 	return 0;
@@ -6726,7 +6249,6 @@ fin_dirty_enq_s_change(Process *p,
     return !0;
 }
 
-#endif /* ERTS_DIRTY_SCHEDULERS */
 
 static ERTS_INLINE int
 check_enqueue_in_prio_queue(Process *c_p,
@@ -6741,14 +6263,12 @@ check_enqueue_in_prio_queue(Process *c_p,
 
     *prq_prio_p = aprio;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (actual & ERTS_PSFLGS_DIRTY_WORK) {
 	int res = check_dirty_enqueue_in_prio_queue(c_p, newp, actual,
 						    aprio, qbit);
 	if (res != ERTS_ENQUEUE_NORMAL_QUEUE)
 	    return res;
     }
-#endif
 
     max_qbit = (actual >> ERTS_PSFLGS_IN_PRQ_MASK_OFFSET) & ERTS_PSFLGS_QMASK;
     max_qbit |= 1 << ERTS_PSFLGS_QMASK_BITS;
@@ -6791,7 +6311,6 @@ select_enqueue_run_queue(int enqueue, int enq_prio, Process *p, erts_aint32_t st
 
 	return NULL;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
     case ERTS_ENQUEUE_DIRTY_CPU_QUEUE:
     case -ERTS_ENQUEUE_DIRTY_CPU_QUEUE:
@@ -6812,7 +6331,6 @@ select_enqueue_run_queue(int enqueue, int enq_prio, Process *p, erts_aint32_t st
 
 	return NULL;
 
-#endif
 
     default: {
 	ErtsRunQueue* runq;
@@ -6822,7 +6340,6 @@ select_enqueue_run_queue(int enqueue, int enq_prio, Process *p, erts_aint32_t st
 
 	runq = erts_get_runq_proc(p);
 
-#ifdef ERTS_SMP
 	if (!(ERTS_PSFLG_BOUND & state)) {
 	    ErtsRunQueue *new_runq = erts_check_emigration_need(runq, enq_prio);
 	    if (new_runq) {
@@ -6830,7 +6347,6 @@ select_enqueue_run_queue(int enqueue, int enq_prio, Process *p, erts_aint32_t st
 		runq = new_runq;
 	    }
 	}
-#endif
 
 	ASSERT(runq);
 
@@ -6858,7 +6374,6 @@ schedule_out_process(ErtsRunQueue *c_rq, erts_aint32_t state, Process *p,
 	running_flgs = ERTS_PSFLG_DIRTY_RUNNING|ERTS_PSFLG_DIRTY_RUNNING_SYS;
     else {
 	running_flgs = ERTS_PSFLG_RUNNING|ERTS_PSFLG_RUNNING_SYS;
-#ifdef ERTS_DIRTY_SCHEDULERS
         if (state & ERTS_PSFLG_DIRTY_ACTIVE_SYS
             && (p->flags & (F_DELAY_GC|F_DISABLE_GC))) {
             /*
@@ -6872,11 +6387,10 @@ schedule_out_process(ErtsRunQueue *c_rq, erts_aint32_t state, Process *p,
              */
             ASSERT(!(p->flags & (F_DIRTY_CLA | F_DIRTY_GC_HIBERNATE)));
 
-            state = erts_smp_atomic32_read_band_nob(&p->state,
+            state = erts_atomic32_read_band_nob(&p->state,
                                                     ~ERTS_PSFLG_DIRTY_ACTIVE_SYS);
             state &= ~ERTS_PSFLG_DIRTY_ACTIVE_SYS;
         }
-#endif
     }
 
     a = state;
@@ -6893,7 +6407,7 @@ schedule_out_process(ErtsRunQueue *c_rq, erts_aint32_t state, Process *p,
 	    || (a & (ERTS_PSFLG_ACTIVE|ERTS_PSFLG_SUSPENDED)) == ERTS_PSFLG_ACTIVE) {
 	    enqueue = check_enqueue_in_prio_queue(p, &enq_prio, &n, a);
 	}
-	a = erts_smp_atomic32_cmpxchg_mb(&p->state, n, e);
+	a = erts_atomic32_cmpxchg_mb(&p->state, n, e);
 	if (a == e)
 	    break;
     }
@@ -6905,7 +6419,7 @@ schedule_out_process(ErtsRunQueue *c_rq, erts_aint32_t state, Process *p,
 	if (erts_system_profile_flags.runnable_procs) {
 
 	    /* Status lock prevents out of order "runnable proc" trace msgs */
-	    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p));
+	    ERTS_LC_ASSERT(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p));
 
 	    if (!(a & (ERTS_PSFLG_ACTIVE_SYS|ERTS_PSFLG_DIRTY_ACTIVE_SYS))
 		&& (!(a & ERTS_PSFLG_ACTIVE) || (a & ERTS_PSFLG_SUSPENDED))) {
@@ -6917,15 +6431,10 @@ schedule_out_process(ErtsRunQueue *c_rq, erts_aint32_t state, Process *p,
 	if (proxy)
 	    free_proxy_proc(proxy);
 
-	erts_smp_runq_lock(c_rq);
+	erts_runq_lock(c_rq);
 
-#if !defined(ERTS_SMP)
-        /* Decrement refc if process struct is free... */
-        return !!(n & ERTS_PSFLG_FREE);
-#else
         /* Decrement refc if scheduled out from dirty scheduler... */
 	return !is_normal_sched;
-#endif
     }
     else {
 	Process* sched_p;
@@ -6944,7 +6453,7 @@ schedule_out_process(ErtsRunQueue *c_rq, erts_aint32_t state, Process *p,
 
 	ASSERT(runq);
 
-	erts_smp_runq_lock(runq);
+	erts_runq_lock(runq);
 
         if (is_normal_sched && sched_p == p && ERTS_RUNQ_IX_IS_DIRTY(runq->ix))
             erts_proc_inc_refc(p); /* Needs to be done before enqueue_process() */
@@ -6955,11 +6464,11 @@ schedule_out_process(ErtsRunQueue *c_rq, erts_aint32_t state, Process *p,
 	if (runq == c_rq)
 	    return 0;
 
-	erts_smp_runq_unlock(runq);
+	erts_runq_unlock(runq);
 
 	smp_notify_inc_runq(runq);
 
-	erts_smp_runq_lock(c_rq);
+	erts_runq_lock(c_rq);
 
         /*
          * Decrement refc if process is scheduled out by a
@@ -7007,12 +6516,12 @@ add2runq(int enqueue, erts_aint32_t prio,
 	    sched_p = make_proxy_proc(pxy, proc, prio);
 	}
 
-	erts_smp_runq_lock(runq);
+	erts_runq_lock(runq);
 
 	/* Enqueue the process */
 	enqueue_process(runq, (int) prio, sched_p);
 
-	erts_smp_runq_unlock(runq);
+	erts_runq_unlock(runq);
 	smp_notify_inc_runq(runq);
     }
 }
@@ -7037,7 +6546,7 @@ change_proc_schedule_state(Process *p,
     unsigned int lock_status = (prof_runnable_procs
 				&& !(locks & ERTS_PROC_LOCK_STATUS));
 
-    ERTS_SMP_LC_ASSERT(locks == erts_proc_lc_my_proc_locks(p));
+    ERTS_LC_ASSERT(locks == erts_proc_lc_my_proc_locks(p));
 
     ASSERT(!(a & ERTS_PSFLG_PROXY));
     ASSERT((clear_state_flags & (ERTS_PSFLG_RUNNING
@@ -7052,7 +6561,7 @@ change_proc_schedule_state(Process *p,
 			       | ERTS_PSFLG_ACTIVE_SYS)) == 0);
 
     if (lock_status)
-	erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
 
     while (1) {
 	erts_aint32_t e;
@@ -7076,11 +6585,9 @@ change_proc_schedule_state(Process *p,
 		  | ERTS_PSFLG_DIRTY_RUNNING_SYS
 		  | ERTS_PSFLG_IN_RUNQ
 		  | ERTS_PSFLG_ACTIVE)) == ERTS_PSFLG_ACTIVE
-#ifdef ERTS_DIRTY_SCHEDULERS
 	    || (n & (ERTS_PSFLG_RUNNING
 		     | ERTS_PSFLG_RUNNING_SYS
 		     | ERTS_PSFLG_EXITING)) == ERTS_PSFLG_EXITING
-#endif
 	    ) {
 	    /*
 	     * Active and seemingly need to be enqueued, but
@@ -7090,7 +6597,7 @@ change_proc_schedule_state(Process *p,
 	    enqueue = check_enqueue_in_prio_queue(p, enq_prio_p, &n, a);
 	}
 
-	a = erts_smp_atomic32_cmpxchg_mb(&p->state, n, e);
+	a = erts_atomic32_cmpxchg_mb(&p->state, n, e);
 	if (a == e)
 	    break;
 	if (enqueue == ERTS_ENQUEUE_NOT && n == a)
@@ -7115,7 +6622,7 @@ change_proc_schedule_state(Process *p,
 	}
 
 	if (lock_status)
-	    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
     }
 
 
@@ -7159,7 +6666,7 @@ schedule_process_sys_task(Process *p, erts_aint32_t prio, ErtsProcSysTask *st,
 
     res = 1; /* prepare for success */
     st->next = st->prev = st; /* Prep for empty prio queue */
-    state = erts_smp_atomic32_read_nob(&p->state);
+    state = erts_atomic32_read_nob(&p->state);
     prof_runnable_procs = erts_system_profile_flags.runnable_procs;
     locked = 0;
     free_stqs = NULL;
@@ -7179,9 +6686,9 @@ schedule_process_sys_task(Process *p, erts_aint32_t prio, ErtsProcSysTask *st,
 
     if (!locked) {
 	locked = 1;
-	erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
 
-	state = erts_smp_atomic32_read_nob(&p->state);
+	state = erts_atomic32_read_nob(&p->state);
 	if (state & fail_state) {
 	    *fail_state_p = (state & fail_state);
 	    free_stqs = stqs;
@@ -7225,7 +6732,7 @@ schedule_process_sys_task(Process *p, erts_aint32_t prio, ErtsProcSysTask *st,
 	    n = e = a;
 	    n &= ~ERTS_PSFLGS_ACT_PRIO_MASK;
 	    n |= (prio << ERTS_PSFLGS_ACT_PRIO_OFFSET);
-	    a = erts_smp_atomic32_cmpxchg_nob(&p->state, n, e);    
+	    a = erts_atomic32_cmpxchg_nob(&p->state, n, e);
 	} while (a != e);
 	state = n;
     }
@@ -7235,10 +6742,10 @@ schedule_process_sys_task(Process *p, erts_aint32_t prio, ErtsProcSysTask *st,
     enq_prio = -1;
 
     /* Status lock prevents out of order "runnable proc" trace msgs */
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p));
 
     if (!prof_runnable_procs) {
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
 	locked = 0;
     }
 
@@ -7258,7 +6765,7 @@ schedule_process_sys_task(Process *p, erts_aint32_t prio, ErtsProcSysTask *st,
 		   | ERTS_PSFLG_DIRTY_RUNNING
 		   | ERTS_PSFLG_DIRTY_RUNNING_SYS)))
 	    enqueue = check_enqueue_in_prio_queue(p, &enq_prio, &n, a);
-	a = erts_smp_atomic32_cmpxchg_mb(&p->state, n, e);
+	a = erts_atomic32_cmpxchg_mb(&p->state, n, e);
 	if (a == e)
 	    break;
 	if (a == n && enqueue == ERTS_ENQUEUE_NOT)
@@ -7277,7 +6784,7 @@ schedule_process_sys_task(Process *p, erts_aint32_t prio, ErtsProcSysTask *st,
 	    profile_runnable_proc(p, am_active);
 	}
 
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
 	locked = 0;
     }
 
@@ -7286,12 +6793,12 @@ schedule_process_sys_task(Process *p, erts_aint32_t prio, ErtsProcSysTask *st,
 cleanup:
 
     if (locked)
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
 
     if (free_stqs)
 	proc_sys_task_queues_free(free_stqs);
 
-    ERTS_SMP_LC_ASSERT(!(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p)));
+    ERTS_LC_ASSERT(!(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p)));
 
     return res;
 }
@@ -7301,15 +6808,15 @@ suspend_process(Process *c_p, Process *p)
 {
     erts_aint32_t state;
     int suspended = 0;
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p));
 
-    state = erts_smp_atomic32_read_acqb(&p->state);
+    state = erts_atomic32_read_acqb(&p->state);
 
     if ((state & ERTS_PSFLG_SUSPENDED))
 	suspended = -1;
     else {
 	if (c_p == p) {
-	    state = erts_smp_atomic32_read_bor_relb(&p->state,
+	    state = erts_atomic32_read_bor_relb(&p->state,
 						    ERTS_PSFLG_SUSPENDED);
 	    ASSERT(state & (ERTS_PSFLG_RUNNING
 			    | ERTS_PSFLG_RUNNING_SYS
@@ -7325,7 +6832,7 @@ suspend_process(Process *c_p, Process *p)
 
 		n = e = state;
 		n |= ERTS_PSFLG_SUSPENDED;
-		state = erts_smp_atomic32_cmpxchg_relb(&p->state, n, e);
+		state = erts_atomic32_cmpxchg_relb(&p->state, n, e);
 		if (state == e) {
 		    suspended = 1;
 		    break;
@@ -7370,14 +6877,14 @@ resume_process(Process *p, ErtsProcLocks locks)
     erts_aint32_t state, enq_prio = -1;
     int enqueue;
 
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p));
 
     ASSERT(p->rcount > 0);
 
     if (--p->rcount > 0)  /* multiple suspend */
 	return;
 
-    state = erts_smp_atomic32_read_nob(&p->state);
+    state = erts_atomic32_read_nob(&p->state);
     enqueue = change_proc_schedule_state(p,
 					 ERTS_PSFLG_SUSPENDED,
 					 0,
@@ -7387,7 +6894,6 @@ resume_process(Process *p, ErtsProcLocks locks)
     add2runq(enqueue, enq_prio, p, state, NULL);
 }
 
-#ifdef ERTS_SMP
 
 static ERTS_INLINE void
 sched_resume_wake__(ErtsSchedulerSleepInfo *ssi)
@@ -7398,7 +6904,7 @@ sched_resume_wake__(ErtsSchedulerSleepInfo *ssi)
 			   | ERTS_SSI_FLG_SUSPENDED);
     erts_aint32_t oflgs;
     do {
-	oflgs = erts_smp_atomic32_cmpxchg_relb(&ssi->flags, 0, xflgs);
+	oflgs = erts_atomic32_cmpxchg_relb(&ssi->flags, 0, xflgs);
 	if (oflgs == xflgs) {
 	    erts_sched_finish_poke(ssi, oflgs);
 	    break;
@@ -7413,7 +6919,6 @@ nrml_sched_ix_resume_wake(Uint ix)
     sched_resume_wake__(ERTS_SCHED_SLEEP_INFO_IX(ix));
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 static void
 dcpu_sched_ix_resume_wake(Uint ix)
@@ -7427,7 +6932,6 @@ dio_sched_ix_resume_wake(Uint ix)
     sched_resume_wake__(ERTS_DIRTY_IO_SCHED_SLEEP_INFO_IX(ix));
 }
 
-#endif
 
 static erts_aint32_t
 sched_prep_spin_suspended(ErtsSchedulerSleepInfo *ssi, erts_aint32_t xpct)
@@ -7439,7 +6943,7 @@ sched_prep_spin_suspended(ErtsSchedulerSleepInfo *ssi, erts_aint32_t xpct)
     erts_aint32_t xflgs = xpct;
 
     do {
-	oflgs = erts_smp_atomic32_cmpxchg_acqb(&ssi->flags, nflgs, xflgs);
+	oflgs = erts_atomic32_cmpxchg_acqb(&ssi->flags, nflgs, xflgs);
 	if (oflgs == xflgs)
 	    return nflgs;
 	xflgs = oflgs;
@@ -7456,7 +6960,7 @@ sched_spin_suspended(ErtsSchedulerSleepInfo *ssi, int spincount)
     erts_aint32_t flgs;
 
     do {
-	flgs = erts_smp_atomic32_read_acqb(&ssi->flags);
+	flgs = erts_atomic32_read_acqb(&ssi->flags);
 	if ((flgs & (ERTS_SSI_FLG_SLEEPING
 		     | ERTS_SSI_FLG_WAITING
 		     | ERTS_SSI_FLG_SUSPENDED))
@@ -7475,21 +6979,23 @@ sched_spin_suspended(ErtsSchedulerSleepInfo *ssi, int spincount)
 }
 
 static erts_aint32_t
-sched_set_suspended_sleeptype(ErtsSchedulerSleepInfo *ssi)
+sched_set_suspended_sleeptype(ErtsSchedulerSleepInfo *ssi,
+                              erts_aint32_t sleep_type)
 {
     erts_aint32_t oflgs;
-    erts_aint32_t nflgs = (ERTS_SSI_FLG_SLEEPING
-			   | ERTS_SSI_FLG_TSE_SLEEPING
-			   | ERTS_SSI_FLG_WAITING
-			   | ERTS_SSI_FLG_SUSPENDED);
+    erts_aint32_t nflgs = ((ERTS_SSI_FLG_SLEEPING
+                            | ERTS_SSI_FLG_WAITING
+                            | ERTS_SSI_FLG_SUSPENDED)
+                           | sleep_type);
     erts_aint32_t xflgs = (ERTS_SSI_FLG_SLEEPING
 			   | ERTS_SSI_FLG_WAITING
 			   | ERTS_SSI_FLG_SUSPENDED);
 
+    ASSERT(sleep_type == ERTS_SSI_FLG_TSE_SLEEPING);
     erts_tse_reset(ssi->event);
 
     while (1) {
-	oflgs = erts_smp_atomic32_cmpxchg_acqb(&ssi->flags, nflgs, xflgs);
+	oflgs = erts_atomic32_cmpxchg_acqb(&ssi->flags, nflgs, xflgs);
 	if (oflgs == xflgs)
 	    return nflgs;
 	if ((oflgs & (ERTS_SSI_FLG_SLEEPING
@@ -7507,12 +7013,11 @@ sched_set_suspended_sleeptype(ErtsSchedulerSleepInfo *ssi)
 static void
 init_scheduler_suspend(void)
 {
-    erts_smp_mtx_init(&schdlr_sspnd.mtx, "schdlr_sspnd", NIL,
+    erts_mtx_init(&schdlr_sspnd.mtx, "schdlr_sspnd", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_SCHEDULER);
     schdlr_sspnd.online.normal = 1;
     schdlr_sspnd.curr_online.normal = 1;
     schdlr_sspnd.active.normal = 1;
-#ifdef ERTS_DIRTY_SCHEDULERS
     schdlr_sspnd.online.dirty_cpu = 0;
     schdlr_sspnd.curr_online.dirty_cpu = 0;
     schdlr_sspnd.active.dirty_cpu = 0;
@@ -7520,8 +7025,7 @@ init_scheduler_suspend(void)
     schdlr_sspnd.curr_online.dirty_io = 0;
     schdlr_sspnd.active.dirty_io = 0;
     schdlr_sspnd.last_msb_dirty_type = ERTS_SCHED_DIRTY_IO;
-#endif
-    erts_smp_atomic32_init_nob(&schdlr_sspnd.changing, 0);
+    erts_atomic32_init_nob(&schdlr_sspnd.changing, 0);
     schdlr_sspnd.chngq = NULL;
     schdlr_sspnd.changer = am_false;
     schdlr_sspnd.nmsb.ongoing = 0;
@@ -7552,7 +7056,7 @@ schdlr_sspnd_resume_proc(ErtsSchedType sched_type, Eterm pid)
                            : 0));
     if (p) {
 	resume_process(p, ERTS_PROC_LOCK_STATUS);
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
         if (sched_type != ERTS_SCHED_NORMAL)
             erts_proc_dec_refc(p);
     }
@@ -7581,7 +7085,6 @@ schdlr_sspnd_resume_procs(ErtsSchedType sched_type,
     }
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 static ERTS_INLINE int
 have_dirty_work(void)
@@ -7741,17 +7244,6 @@ msb_scheduler_type_switch(ErtsSchedType sched_type,
     if (exec_type != ERTS_SCHED_NORMAL)
         schdlr_sspnd.last_msb_dirty_type = exec_type;
     else {
-        erts_aint32_t calls;
-        /*
-         * Going back to normal scheduler after
-         * dirty execution; make sure it will check
-         * for I/O...
-         */
-        if (ERTS_USE_MODIFIED_TIMING())
-            calls = ERTS_MODIFIED_TIMING_INPUT_REDS + 1;
-        else
-            calls = INPUT_REDUCTIONS + 1;
-        erts_smp_atomic32_set_nob(&function_calls, calls);
 
         if ((nrml_prio == ERTS_MSB_NONE_PRIO_BIT)
             & ((dcpu_prio != ERTS_MSB_NONE_PRIO_BIT)
@@ -7786,7 +7278,7 @@ msb_scheduler_type_switch(ErtsSchedType sched_type,
 #else
     (void)
 #endif
-        erts_smp_atomic32_read_bset_mb(&esdp->ssi->flags,
+        erts_atomic32_read_bset_mb(&esdp->ssi->flags,
                                        (ERTS_SSI_FLG_SUSPENDED
                                         | ERTS_SSI_FLG_MSB_EXEC),
                                        ERTS_SSI_FLG_SUSPENDED);
@@ -7813,7 +7305,7 @@ msb_scheduler_type_switch(ErtsSchedType sched_type,
 #else
     (void)
 #endif
-        erts_smp_atomic32_read_bset_mb(&exec_rq->scheduler->ssi->flags,
+        erts_atomic32_read_bset_mb(&exec_rq->scheduler->ssi->flags,
                                        (ERTS_SSI_FLG_SUSPENDED
                                         | ERTS_SSI_FLG_MSB_EXEC),
                                        ERTS_SSI_FLG_MSB_EXEC);
@@ -7825,7 +7317,34 @@ msb_scheduler_type_switch(ErtsSchedType sched_type,
 
 }
 
-#endif
+static ERTS_INLINE void
+suspend_normal_scheduler_sleep(ErtsSchedulerData *esdp)
+{
+    ErtsSchedulerSleepInfo *ssi = esdp->ssi;
+    erts_aint32_t flgs = sched_spin_suspended(ssi,
+                                              ERTS_SCHED_SUSPEND_SLEEP_SPINCOUNT);
+    if (flgs == (ERTS_SSI_FLG_SLEEPING
+                 | ERTS_SSI_FLG_WAITING
+                 | ERTS_SSI_FLG_SUSPENDED)) {
+        flgs = sched_set_suspended_sleeptype(ssi, ERTS_SSI_FLG_TSE_SLEEPING);
+        if (flgs == (ERTS_SSI_FLG_SLEEPING
+                     | ERTS_SSI_FLG_TSE_SLEEPING
+                     | ERTS_SSI_FLG_WAITING
+                     | ERTS_SSI_FLG_SUSPENDED)) {
+            int res;
+
+            do {
+                res = erts_tse_wait(ssi->event);
+            } while (res == EINTR);
+        }
+    }
+}
+
+static ERTS_INLINE void
+suspend_dirty_scheduler_sleep(ErtsSchedulerData *esdp)
+{
+    suspend_normal_scheduler_sleep(esdp);
+}
 
 static void
 suspend_scheduler(ErtsSchedulerData *esdp)
@@ -7853,14 +7372,6 @@ suspend_scheduler(ErtsSchedulerData *esdp)
      */
 
 
-#if !defined(ERTS_DIRTY_SCHEDULERS)
-
-    sched_type = ERTS_SCHED_NORMAL;
-    online_flag = ERTS_SCHDLR_SSPND_CHNG_ONLN;
-    no = esdp->no;
-    ASSERT(no != 1);
-
-#else
 
     sched_type = esdp->type;
     switch (sched_type) {
@@ -7881,25 +7392,24 @@ suspend_scheduler(ErtsSchedulerData *esdp)
         return;
     }
 
-    if (erts_smp_atomic32_read_nob(&ssi->flags) & ERTS_SSI_FLG_MSB_EXEC) {
+    if (erts_atomic32_read_nob(&ssi->flags) & ERTS_SSI_FLG_MSB_EXEC) {
         ASSERT(no == 1);
         if (!msb_scheduler_type_switch(sched_type, esdp, no))
             return;
         /* Suspend and let scheduler 1 of another type execute... */
     }
 
-#endif
 
     if (sched_type != ERTS_SCHED_NORMAL) {
         dirty_active(esdp, -1);
-	erts_smp_runq_unlock(esdp->run_queue);
+	erts_runq_unlock(esdp->run_queue);
         dirty_sched_wall_time_change(esdp, 0);
     }
     else {
         if (no != 1)
             evacuate_run_queue(esdp->run_queue, &sbp);
 
-	erts_smp_runq_unlock(esdp->run_queue);
+	erts_runq_unlock(esdp->run_queue);
 
 	erts_sched_check_cpu_bind_prep_suspend(esdp);
 
@@ -7907,14 +7417,14 @@ suspend_scheduler(ErtsSchedulerData *esdp)
 	    profile_scheduler(make_small(esdp->no), am_inactive);
     }
 
-    erts_smp_mtx_lock(&schdlr_sspnd.mtx);
+    erts_mtx_lock(&schdlr_sspnd.mtx);
 
     flgs = sched_prep_spin_suspended(ssi, ERTS_SSI_FLG_SUSPENDED);
     if (flgs & ERTS_SSI_FLG_SUSPENDED) {
 
 	schdlr_sspnd_dec_nscheds(&schdlr_sspnd.active, sched_type);
 
-	changing = erts_smp_atomic32_read_nob(&schdlr_sspnd.changing);
+	changing = erts_atomic32_read_nob(&schdlr_sspnd.changing);
 
 	while (1) {
 
@@ -7946,7 +7456,7 @@ suspend_scheduler(ErtsSchedulerData *esdp)
 
 		    if (clr_flg) {
 			ErtsProcList *plp, *end_plp;
-			changing = erts_smp_atomic32_read_band_nob(&schdlr_sspnd.changing,
+			changing = erts_atomic32_read_band_nob(&schdlr_sspnd.changing,
 								   ~clr_flg);
 			changing &= ~clr_flg;
 			(void) erts_proclist_fetch(&msb[i]->chngq, &end_plp);
@@ -7992,7 +7502,7 @@ suspend_scheduler(ErtsSchedulerData *esdp)
 			== schdlr_sspnd_get_nscheds(&schdlr_sspnd.curr_online,
 						    sched_type))) {
 		    ErtsProcList *plp;
-		    changing = erts_smp_atomic32_read_band_nob(&schdlr_sspnd.changing,
+		    changing = erts_atomic32_read_band_nob(&schdlr_sspnd.changing,
 							       ~online_flag);
 		    changing &= ~online_flag;
 		    if (sched_type == ERTS_SCHED_NORMAL) {
@@ -8014,23 +7524,24 @@ suspend_scheduler(ErtsSchedulerData *esdp)
 	    }
 
 	    if (curr_online) {
-		flgs = erts_smp_atomic32_read_acqb(&ssi->flags);
+		flgs = erts_atomic32_read_acqb(&ssi->flags);
 		if (!(flgs & ERTS_SSI_FLG_SUSPENDED))
 		    break;
 	    }
-	    erts_smp_mtx_unlock(&schdlr_sspnd.mtx);
+	    erts_mtx_unlock(&schdlr_sspnd.mtx);
 
 	    schdlr_sspnd_resume_procs(sched_type, &resume);
 
 	    while (1) {
-		ErtsMonotonicTime current_time;
-		erts_aint32_t flgs;
-
 		if (sched_type != ERTS_SCHED_NORMAL)
-		    aux_work = 0;
-		else {
+                    suspend_dirty_scheduler_sleep(esdp);
+		else
+                {
+                    ErtsMonotonicTime current_time, timeout_time;
                     int evacuate = no == 1 ? 0 : !ERTS_EMPTY_RUNQ(esdp->run_queue);
 
+		    ASSERT(sched_type == ERTS_SCHED_NORMAL);
+
 		    aux_work = erts_atomic32_read_acqb(&ssi->aux_work);
 
 		    if (aux_work|evacuate) {
@@ -8046,123 +7557,62 @@ suspend_scheduler(ErtsSchedulerData *esdp)
 			if (aux_work && erts_thr_progress_update(esdp))
 			    erts_thr_progress_leader_update(esdp);
 			if (evacuate) {
-			    erts_smp_runq_lock(esdp->run_queue);
+			    erts_runq_lock(esdp->run_queue);
 			    evacuate_run_queue(esdp->run_queue, &sbp);
-			    erts_smp_runq_unlock(esdp->run_queue);
+			    erts_runq_unlock(esdp->run_queue);
 			}
 		    }
 
-		}
 
-		if (aux_work) {
-		    ASSERT(sched_type == ERTS_SCHED_NORMAL);
-		    current_time = erts_get_monotonic_time(esdp);
-		    if (current_time >= erts_next_timeout_time(esdp->next_tmo_ref)) {
-			if (!thr_prgr_active) {
-			    erts_thr_progress_active(esdp, thr_prgr_active = 1);
-			    sched_wall_time_change(esdp, 1);
-			}
-			erts_bump_timers(esdp->timer_wheel, current_time);
-		    }
-		}
-		else {
-		    ErtsMonotonicTime timeout_time;
-		    int do_timeout;
+                    if (aux_work)
+                        timeout_time = erts_next_timeout_time(esdp->next_tmo_ref);
+                    else
+                        timeout_time = erts_check_next_timeout_time(esdp);
 
-		    if (sched_type == ERTS_SCHED_NORMAL) {
-			timeout_time = erts_check_next_timeout_time(esdp);
-			current_time = erts_get_monotonic_time(esdp);
-			do_timeout = (current_time >= timeout_time);
-		    }
-		    else {
-			timeout_time = ERTS_MONOTONIC_TIME_MAX;
-			current_time = 0;
-			do_timeout = 0;
-		    }
+                    current_time = erts_get_monotonic_time(esdp);
 
-		    if (do_timeout) {
-			ASSERT(sched_type == ERTS_SCHED_NORMAL);
-			if (!thr_prgr_active) {
-			    erts_thr_progress_active(esdp, thr_prgr_active = 1);
-			    sched_wall_time_change(esdp, 1);
-			}
-		    }
-		    else {
-			if (sched_type == ERTS_SCHED_NORMAL) {
-			    if (thr_prgr_active) {
-				erts_thr_progress_active(esdp, thr_prgr_active = 0);
-				sched_wall_time_change(esdp, 0);
-			    }
-			    erts_thr_progress_prepare_wait(esdp);
-			}
-			flgs = sched_spin_suspended(ssi,
-						    ERTS_SCHED_SUSPEND_SLEEP_SPINCOUNT);
-			if (flgs == (ERTS_SSI_FLG_SLEEPING
-				     | ERTS_SSI_FLG_WAITING
-				     | ERTS_SSI_FLG_SUSPENDED)) {
-			    flgs = sched_set_suspended_sleeptype(ssi);
-			    if (flgs == (ERTS_SSI_FLG_SLEEPING
-					 | ERTS_SSI_FLG_TSE_SLEEPING
-					 | ERTS_SSI_FLG_WAITING
-					 | ERTS_SSI_FLG_SUSPENDED)) {
-				int res;
-
-				if (sched_type == ERTS_SCHED_NORMAL)
-				    current_time = erts_get_monotonic_time(esdp);
-				else
-				    current_time = 0;
-
-				do {
-				    Sint64 timeout;
-				    if (current_time >= timeout_time)
-					break;
-				    if (sched_type != ERTS_SCHED_NORMAL)
-					timeout = -1;
-				    else
-					timeout = ERTS_MONOTONIC_TO_NSEC(timeout_time
-									 - current_time
-									 - 1) + 1;
-				    res = erts_tse_twait(ssi->event, timeout);
-
-				    if (sched_type == ERTS_SCHED_NORMAL)
-					current_time = erts_get_monotonic_time(esdp);
-				    else
-					current_time = 0;
-
-				} while (res == EINTR);
-			    }
-			}
-			if (sched_type == ERTS_SCHED_NORMAL)
-			    erts_thr_progress_finalize_wait(esdp);
-		    }
+                    if (!aux_work && current_time < timeout_time) {
+                        /* go to sleep... */
+                        if (thr_prgr_active) {
+                            erts_thr_progress_active(esdp, thr_prgr_active = 0);
+                            sched_wall_time_change(esdp, 0);
+                        }
+                        erts_thr_progress_prepare_wait(NULL);
+                        suspend_normal_scheduler_sleep(esdp);
+                        erts_thr_progress_finalize_wait(NULL);
+                        current_time = erts_get_monotonic_time(esdp);
+                    }
 
-		    if (current_time >= timeout_time) {
-			ASSERT(sched_type == ERTS_SCHED_NORMAL);
-			erts_bump_timers(esdp->timer_wheel, current_time);
-		    }
-		}
+                    if (current_time >= timeout_time) {
+                        if (!thr_prgr_active) {
+                            erts_thr_progress_active(esdp, thr_prgr_active = 1);
+                            sched_wall_time_change(esdp, 1);
+                        }
+                        erts_bump_timers(esdp->timer_wheel, current_time);
+                    }
+                }
 
 		flgs = sched_prep_spin_suspended(ssi, (ERTS_SSI_FLG_WAITING
 						       | ERTS_SSI_FLG_SUSPENDED));
 		if (!(flgs & ERTS_SSI_FLG_SUSPENDED))
 		    break;
-		changing = erts_smp_atomic32_read_nob(&schdlr_sspnd.changing);
+		changing = erts_atomic32_read_nob(&schdlr_sspnd.changing);
 		if (changing)
 		    break;
 	    }
 
-	    erts_smp_mtx_lock(&schdlr_sspnd.mtx);
-	    changing = erts_smp_atomic32_read_nob(&schdlr_sspnd.changing);
+	    erts_mtx_lock(&schdlr_sspnd.mtx);
+	    changing = erts_atomic32_read_nob(&schdlr_sspnd.changing);
 	}
 
 	schdlr_sspnd_inc_nscheds(&schdlr_sspnd.active, sched_type);
-	changing = erts_smp_atomic32_read_nob(&schdlr_sspnd.changing);
+	changing = erts_atomic32_read_nob(&schdlr_sspnd.changing);
         if (changing) {
             if ((changing & ERTS_SCHDLR_SSPND_CHNG_MSB)
                 && !schdlr_sspnd.msb.ongoing
                 && schdlr_sspnd_eq_nscheds(&schdlr_sspnd.online,
                                            &schdlr_sspnd.active)) {
-                erts_smp_atomic32_read_band_nob(&schdlr_sspnd.changing,
+                erts_atomic32_read_band_nob(&schdlr_sspnd.changing,
                                                 ~ERTS_SCHDLR_SSPND_CHNG_MSB);
             }
             if ((changing & ERTS_SCHDLR_SSPND_CHNG_NMSB)
@@ -8171,14 +7621,14 @@ suspend_scheduler(ErtsSchedulerData *esdp)
                                              ERTS_SCHED_NORMAL)
                     == schdlr_sspnd_get_nscheds(&schdlr_sspnd.active,
                                                 ERTS_SCHED_NORMAL))) {
-                erts_smp_atomic32_read_band_nob(&schdlr_sspnd.changing,
+                erts_atomic32_read_band_nob(&schdlr_sspnd.changing,
                                                 ~ERTS_SCHDLR_SSPND_CHNG_NMSB);
             }
         }
 	ASSERT(no <= schdlr_sspnd_get_nscheds(&schdlr_sspnd.online, sched_type));
     }
 
-    erts_smp_mtx_unlock(&schdlr_sspnd.mtx);
+    erts_mtx_unlock(&schdlr_sspnd.mtx);
 
     schdlr_sspnd_resume_procs(sched_type, &resume);
 
@@ -8197,7 +7647,7 @@ suspend_scheduler(ErtsSchedulerData *esdp)
         }
     }
 
-    erts_smp_runq_lock(esdp->run_queue);
+    erts_runq_lock(esdp->run_queue);
     non_empty_runq(esdp->run_queue);
 
     if (sched_type != ERTS_SCHED_NORMAL)
@@ -8221,7 +7671,7 @@ erts_schedulers_state(Uint *total,
 {
     if (active || online || dirty_cpu_online
 	|| dirty_cpu_active || dirty_io_active) {
-	erts_smp_mtx_lock(&schdlr_sspnd.mtx);
+	erts_mtx_lock(&schdlr_sspnd.mtx);
 	if (active)
 	    *active = schdlr_sspnd_get_nscheds(&schdlr_sspnd.active,
 					       ERTS_SCHED_NORMAL);
@@ -8237,7 +7687,7 @@ erts_schedulers_state(Uint *total,
 	if (dirty_io_active)
 	    *dirty_io_active = schdlr_sspnd_get_nscheds(&schdlr_sspnd.active,
 							ERTS_SCHED_DIRTY_IO);
-	erts_smp_mtx_unlock(&schdlr_sspnd.mtx);
+	erts_mtx_unlock(&schdlr_sspnd.mtx);
     }
 
     if (total)
@@ -8253,7 +7703,7 @@ abort_sched_onln_chng_waitq(Process *p)
 {
     Eterm resume = NIL;
 
-    erts_smp_mtx_lock(&schdlr_sspnd.mtx);
+    erts_mtx_lock(&schdlr_sspnd.mtx);
 
 #ifdef DEBUG
     {
@@ -8303,7 +7753,7 @@ abort_sched_onln_chng_waitq(Process *p)
 	}
     }
 
-    erts_smp_mtx_unlock(&schdlr_sspnd.mtx);
+    erts_mtx_unlock(&schdlr_sspnd.mtx);
 
     if (is_internal_pid(resume))
 	schdlr_sspnd_resume_proc(ERTS_SCHED_NORMAL, resume);
@@ -8320,11 +7770,7 @@ erts_set_schedulers_online(Process *p,
     erts_aint32_t changing = 0, change_flags;
     int online, increase;
     ErtsProcList *plp;
-#ifdef ERTS_DIRTY_SCHEDULERS
     int dirty_no, change_dirty, dirty_online;
-#else
-    ASSERT(!dirty_only);
-#endif
 
     if (new_no < 1)
 	return ERTS_SCHDLR_SSPND_EINVAL;
@@ -8333,11 +7779,9 @@ erts_set_schedulers_online(Process *p,
     else if (erts_no_schedulers < new_no)
 	return ERTS_SCHDLR_SSPND_EINVAL;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (dirty_only)
 	resume_proc = 0;
     else
-#endif
     {
 	resume_proc = 1;
 	/*
@@ -8346,23 +7790,21 @@ erts_set_schedulers_online(Process *p,
 	 * race...
 	 */
 	if (!(plocks & ERTS_PROC_LOCK_STATUS))
-	    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
 	suspend_process(p, p);
 	if (!(plocks & ERTS_PROC_LOCK_STATUS))
-	    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
     }
 
-    erts_smp_mtx_lock(&schdlr_sspnd.mtx);
+    erts_mtx_lock(&schdlr_sspnd.mtx);
 
     change_flags = 0;
     have_unlocked_plocks = 0;
     no = (int) new_no;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (!dirty_only)
-#endif
     {
-	changing = erts_smp_atomic32_read_nob(&schdlr_sspnd.changing);
+	changing = erts_atomic32_read_nob(&schdlr_sspnd.changing);
 	if (changing & ERTS_SCHDLR_SSPND_CHNG_ONLN) {
 	enqueue_wait:
 	    p->flags |= F_SCHDLR_ONLN_WAITQ;
@@ -8388,12 +7830,6 @@ erts_set_schedulers_online(Process *p,
 
     *old_no = online = schdlr_sspnd_get_nscheds(&schdlr_sspnd.online,
 						ERTS_SCHED_NORMAL);
-#ifndef ERTS_DIRTY_SCHEDULERS
-    if (no == online) {
-	res = ERTS_SCHDLR_SSPND_DONE;
-	goto done;
-    }
-#else /* ERTS_DIRTY_SCHEDULERS */
     dirty_online = schdlr_sspnd_get_nscheds(&schdlr_sspnd.online,
 					    ERTS_SCHED_DIRTY_CPU);
     if (dirty_only)
@@ -8445,7 +7881,6 @@ erts_set_schedulers_online(Process *p,
     if (dirty_only)
 	increase = (dirty_no > dirty_online);
     else
-#endif /* ERTS_DIRTY_SCHEDULERS */
     {
 	change_flags |= ERTS_SCHDLR_SSPND_CHNG_ONLN;
 	schdlr_sspnd_set_nscheds(&schdlr_sspnd.online,
@@ -8454,12 +7889,11 @@ erts_set_schedulers_online(Process *p,
 	increase = (no > online);
     }
 
-    erts_smp_atomic32_read_bor_nob(&schdlr_sspnd.changing, change_flags);
+    erts_atomic32_read_bor_nob(&schdlr_sspnd.changing, change_flags);
 
     res = ERTS_SCHDLR_SSPND_DONE;
     if (increase) {
 	int ix;
-#ifdef ERTS_DIRTY_SCHEDULERS
 	if (change_dirty) {
 	    ErtsSchedulerSleepInfo* ssi;
 	    if (schdlr_sspnd.msb.ongoing) {
@@ -8473,7 +7907,6 @@ erts_set_schedulers_online(Process *p,
 	    }
 	}
 	if (!dirty_only)
-#endif
 	{
 	    if (schdlr_sspnd.msb.ongoing|schdlr_sspnd.nmsb.ongoing) {
 		for (ix = online; ix < no; ix++)
@@ -8482,7 +7915,7 @@ erts_set_schedulers_online(Process *p,
 	    else {
 		if (plocks) {
 		    have_unlocked_plocks = 1;
-		    erts_smp_proc_unlock(p, plocks);
+		    erts_proc_unlock(p, plocks);
 		}
 		change_no_used_runqs(no);
 
@@ -8495,7 +7928,6 @@ erts_set_schedulers_online(Process *p,
 	}
     }
     else /* if decrease */ {
-#ifdef ERTS_DIRTY_SCHEDULERS
 	if (change_dirty) {
 	    if (schdlr_sspnd.msb.ongoing) {
 		for (ix = dirty_no; ix < dirty_online; ix++)
@@ -8513,7 +7945,6 @@ erts_set_schedulers_online(Process *p,
 	    }
 	}
 	if (!dirty_only)
-#endif
 	{
 	    if (schdlr_sspnd.msb.ongoing|schdlr_sspnd.nmsb.ongoing) {
 		for (ix = no; ix < online; ix++)
@@ -8522,7 +7953,7 @@ erts_set_schedulers_online(Process *p,
 	    else {
 		if (plocks) {
 		    have_unlocked_plocks = 1;
-		    erts_smp_proc_unlock(p, plocks);
+		    erts_proc_unlock(p, plocks);
 		}
 
 		change_no_used_runqs(no);
@@ -8551,17 +7982,17 @@ done:
 	   <= schdlr_sspnd_get_nscheds(&schdlr_sspnd.online,
 				       ERTS_SCHED_NORMAL));
 
-    erts_smp_mtx_unlock(&schdlr_sspnd.mtx);
+    erts_mtx_unlock(&schdlr_sspnd.mtx);
 
     if (have_unlocked_plocks)
-	erts_smp_proc_lock(p, plocks);
+	erts_proc_lock(p, plocks);
 
     if (resume_proc) {
 	if (!(plocks & ERTS_PROC_LOCK_STATUS))
-	    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
 	resume_process(p, plocks|ERTS_PROC_LOCK_STATUS);
 	if (!(plocks & ERTS_PROC_LOCK_STATUS))
-	    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
     }
 
     return res;
@@ -8599,13 +8030,13 @@ erts_block_multi_scheduling(Process *p, ErtsProcLocks plocks, int on, int normal
     else {
 	resume_proc = 1;
 	if (!(plocks & ERTS_PROC_LOCK_STATUS))
-	    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
 	suspend_process(p, p);
 	if (!(plocks & ERTS_PROC_LOCK_STATUS))
-	    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
     }
 
-    erts_smp_mtx_lock(&schdlr_sspnd.mtx);
+    erts_mtx_lock(&schdlr_sspnd.mtx);
     if (on) { /* ------ BLOCK ------ */
 	if (msbp->chngq) {
 	    ASSERT(msbp->ongoing);
@@ -8635,12 +8066,12 @@ erts_block_multi_scheduling(Process *p, ErtsProcLocks plocks, int on, int normal
 	    p->flags |= have_blckd_flg;
 	    if (plocks) {
 		have_unlocked_plocks = 1;
-		erts_smp_proc_unlock(p, plocks);
+		erts_proc_unlock(p, plocks);
 	    }
 	    ASSERT(!msbp->ongoing);
 	    msbp->ongoing = 1;
 
-            erts_smp_atomic32_read_bor_nob(&schdlr_sspnd.changing,
+            erts_atomic32_read_bor_nob(&schdlr_sspnd.changing,
                                            chng_flg);
             change_no_used_runqs(1);
             for (ix = 1; ix < erts_no_run_queues; ix++)
@@ -8651,21 +8082,19 @@ erts_block_multi_scheduling(Process *p, ErtsProcLocks plocks, int on, int normal
                 wake_scheduler(rq);
             }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
             if (!normal) {
                 ERTS_RUNQ_FLGS_SET_NOB(ERTS_RUNQ_IX(0), ERTS_RUNQ_FLG_MSB_EXEC);
-                erts_smp_atomic32_read_bor_nob(&ERTS_RUNQ_IX(0)->scheduler->ssi->flags,
+                erts_atomic32_read_bor_nob(&ERTS_RUNQ_IX(0)->scheduler->ssi->flags,
                                                ERTS_SSI_FLG_MSB_EXEC);
                 for (ix = 0; ix < erts_no_dirty_cpu_schedulers; ix++)
                     dcpu_sched_ix_suspend_wake(ix);
                 for (ix = 0; ix < erts_no_dirty_io_schedulers; ix++)
                     dio_sched_ix_suspend_wake(ix);
             }
-#endif
 
         wait_until_msb:
 
-            ASSERT(chng_flg & erts_smp_atomic32_read_nob(&schdlr_sspnd.changing));
+            ASSERT(chng_flg & erts_atomic32_read_nob(&schdlr_sspnd.changing));
 
             plp = proclist_create(p);
             erts_proclist_store_last(&msbp->chngq, plp);
@@ -8706,14 +8135,14 @@ erts_block_multi_scheduling(Process *p, ErtsProcLocks plocks, int on, int normal
 	}
 	if (!msbp->blckrs && !msbp->chngq) {
 	    int online;
-	    erts_smp_atomic32_read_bor_nob(&schdlr_sspnd.changing,
+	    erts_atomic32_read_bor_nob(&schdlr_sspnd.changing,
 					   chng_flg);
 	    p->flags &= ~have_blckd_flg;
 	    msbp->ongoing = 0;
             if (!(schdlr_sspnd.msb.ongoing|schdlr_sspnd.nmsb.ongoing)) {
                 if (plocks) {
 		    have_unlocked_plocks = 1;
-		    erts_smp_proc_unlock(p, plocks);
+		    erts_proc_unlock(p, plocks);
 		}
 
                 online = (int) schdlr_sspnd_get_nscheds(&schdlr_sspnd.online,
@@ -8727,7 +8156,6 @@ erts_block_multi_scheduling(Process *p, ErtsProcLocks plocks, int on, int normal
 		for (ix = online; ix < erts_no_run_queues; ix++)
 		    suspend_run_queue(ERTS_RUNQ_IX(ix));
 	    }
-#ifdef ERTS_DIRTY_SCHEDULERS
             if (!schdlr_sspnd.msb.ongoing) {
                 /* Get rid of msb-exec flag in run-queue of scheduler 1 */
                 resume_run_queue(ERTS_RUNQ_IX(0));
@@ -8738,7 +8166,6 @@ erts_block_multi_scheduling(Process *p, ErtsProcLocks plocks, int on, int normal
 		for (ix = 0; ix < erts_no_dirty_io_schedulers; ix++)
 		    dio_sched_ix_resume_wake(ix);
 	    }
-#endif
 	}
 
     unblock_res:
@@ -8750,17 +8177,17 @@ erts_block_multi_scheduling(Process *p, ErtsProcLocks plocks, int on, int normal
 	    res = ERTS_SCHDLR_SSPND_DONE;
     }
 
-    erts_smp_mtx_unlock(&schdlr_sspnd.mtx);
+    erts_mtx_unlock(&schdlr_sspnd.mtx);
 
     if (have_unlocked_plocks)
-	erts_smp_proc_lock(p, plocks);
+	erts_proc_lock(p, plocks);
 
     if (resume_proc) {
 	if (!(plocks & ERTS_PROC_LOCK_STATUS))
-	    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
 	resume_process(p, plocks|ERTS_PROC_LOCK_STATUS);
 	if (!(plocks & ERTS_PROC_LOCK_STATUS))
-	    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
     }
 
     return res;
@@ -8770,14 +8197,14 @@ int
 erts_is_multi_scheduling_blocked(void)
 {
     int res;
-    erts_smp_mtx_lock(&schdlr_sspnd.mtx);
+    erts_mtx_lock(&schdlr_sspnd.mtx);
     if (schdlr_sspnd.msb.blckrs)
 	res = 1;
     else if (schdlr_sspnd.nmsb.blckrs)
 	res = -1;
     else
 	res = 0;
-    erts_smp_mtx_unlock(&schdlr_sspnd.mtx);
+    erts_mtx_unlock(&schdlr_sspnd.mtx);
     return res;
 }
 
@@ -8789,7 +8216,7 @@ erts_multi_scheduling_blockers(Process *p, int normal)
 
     msbp = normal ? &schdlr_sspnd.nmsb : &schdlr_sspnd.msb;
 
-    erts_smp_mtx_lock(&schdlr_sspnd.mtx);
+    erts_mtx_lock(&schdlr_sspnd.mtx);
     if (!erts_proclist_is_empty(msbp->blckrs)) {
 	Eterm *hp, *hp_end;
 	ErtsProcList *plp1, *plp2;
@@ -8817,7 +8244,7 @@ erts_multi_scheduling_blockers(Process *p, int normal)
 	}
 	HRelease(p, hp_end, hp);
     }
-    erts_smp_mtx_unlock(&schdlr_sspnd.mtx);
+    erts_mtx_unlock(&schdlr_sspnd.mtx);
     return res;
 }
 
@@ -8827,10 +8254,9 @@ sched_thread_func(void *vesdp)
     ErtsThrPrgrCallbacks callbacks;
     ErtsSchedulerData *esdp = vesdp;
     Uint no = esdp->no;
-#ifdef ERTS_SMP
     erts_tse_t *tse;
-#endif
 
+    erts_port_task_pre_alloc_init_thread();
     erts_sched_init_time_sup(esdp);
 
     if (no == 1)
@@ -8839,7 +8265,6 @@ sched_thread_func(void *vesdp)
     (void) ERTS_RUNQ_FLGS_SET_NOB(esdp->run_queue,
 				  ERTS_RUNQ_FLG_EXEC);
 
-#ifdef ERTS_SMP
     tse = erts_tse_fetch();
     erts_tse_prepare_timed(tse);
     ERTS_SCHED_SLEEP_INFO_IX(no - 1)->event = tse;
@@ -8853,7 +8278,6 @@ sched_thread_func(void *vesdp)
 
     erts_thr_progress_register_managed_thread(esdp, &callbacks, 0);
     erts_alloc_register_scheduler(vesdp);
-#endif
 #ifdef ERTS_ENABLE_LOCK_CHECK
     {
 	char buf[31];
@@ -8862,18 +8286,14 @@ sched_thread_func(void *vesdp)
     }
 #endif
     erts_tsd_set(sched_data_key, vesdp);
-#ifdef ERTS_SMP
 #if HAVE_ERTS_MSEG
     erts_mseg_late_init();
 #endif
-#if ERTS_USE_ASYNC_READY_Q
     esdp->aux_work_data.async_ready.queue = erts_get_async_ready_queue(no);
-#endif
 
     erts_sched_init_check_cpu_bind(esdp);
 
     erts_proc_lock_prepare_proc_lock_waiter();
-#endif
 
 #ifdef HIPE
     hipe_thread_signal_init();
@@ -8898,8 +8318,6 @@ sched_thread_func(void *vesdp)
     return NULL;
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
-#ifdef ERTS_SMP
 static void*
 sched_dirty_cpu_thread_func(void *vesdp)
 {
@@ -8929,9 +8347,7 @@ sched_dirty_cpu_thread_func(void *vesdp)
     }
 #endif
     erts_tsd_set(sched_data_key, vesdp);
-#if ERTS_USE_ASYNC_READY_Q
     esdp->aux_work_data.async_ready.queue = NULL;
-#endif
 
     erts_proc_lock_prepare_proc_lock_waiter();
 
@@ -8977,9 +8393,7 @@ sched_dirty_io_thread_func(void *vesdp)
     }
 #endif
     erts_tsd_set(sched_data_key, vesdp);
-#if ERTS_USE_ASYNC_READY_Q
     esdp->aux_work_data.async_ready.queue = NULL;
-#endif
 
     erts_proc_lock_prepare_proc_lock_waiter();
 
@@ -8995,40 +8409,38 @@ sched_dirty_io_thread_func(void *vesdp)
 	     no);
     return NULL;
 }
-#endif
-#endif
-
-static ethr_tid aux_tid;
 
 void
 erts_start_schedulers(void)
 {
+    ethr_tid tid;
     int res = 0;
     Uint actual;
     Uint wanted = erts_no_schedulers;
     Uint wanted_no_schedulers = erts_no_schedulers;
     char name[16];
     ethr_thr_opts opts = ETHR_THR_OPTS_DEFAULT_INITER;
+    int ix;
 
     opts.detached = 1;
 
     opts.name = name;
 
-#ifdef ERTS_SMP
     if (erts_runq_supervision_interval) {
 	opts.suggested_stack_size = 16;
         erts_snprintf(opts.name, 16, "runq_supervisor");
 	erts_atomic_init_nob(&runq_supervisor_sleeping, 0);
 	if (0 != ethr_event_init(&runq_supervision_event))
 	    erts_exit(ERTS_ERROR_EXIT, "Failed to create run-queue supervision event\n");
-	if (0 != ethr_thr_create(&runq_supervisor_tid,
-				 runq_supervisor,
-				 NULL,
-				 &opts))
-	    erts_exit(ERTS_ERROR_EXIT, "Failed to create run-queue supervision thread\n");
+        res = ethr_thr_create(&runq_supervisor_tid,
+                              runq_supervisor,
+                              NULL,
+                              &opts);
+	if (0 != res)
+	    erts_exit(ERTS_ERROR_EXIT, "Failed to create run-queue supervision thread, "
+                      "error = %d\n", res);
 
     }
-#endif
 
     opts.suggested_stack_size = erts_sched_thread_suggested_stack_size;
 
@@ -9054,17 +8466,14 @@ erts_start_schedulers(void)
     }
     erts_no_schedulers = actual;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
-#ifdef ERTS_SMP
     {
-	int ix;
 	for (ix = 0; ix < erts_no_dirty_cpu_schedulers; ix++) {
 	    ErtsSchedulerData *esdp = ERTS_DIRTY_CPU_SCHEDULER_IX(ix);
 	    erts_snprintf(opts.name, 16, "%d_dirty_cpu_scheduler", ix + 1);
             opts.suggested_stack_size = erts_dcpu_sched_thread_suggested_stack_size;
 	    res = ethr_thr_create(&esdp->tid,sched_dirty_cpu_thread_func,(void*)esdp,&opts);
 	    if (res != 0)
-		erts_exit(ERTS_ERROR_EXIT, "Failed to create dirty cpu scheduler thread %d\n", ix);
+		erts_exit(ERTS_ERROR_EXIT, "Failed to create dirty cpu scheduler thread %d, error = %d\n", ix, res);
 	}
 	for (ix = 0; ix < erts_no_dirty_io_schedulers; ix++) {
 	    ErtsSchedulerData *esdp = ERTS_DIRTY_IO_SCHEDULER_IX(ix);
@@ -9072,19 +8481,25 @@ erts_start_schedulers(void)
             opts.suggested_stack_size = erts_dio_sched_thread_suggested_stack_size;
 	    res = ethr_thr_create(&esdp->tid,sched_dirty_io_thread_func,(void*)esdp,&opts);
 	    if (res != 0)
-		erts_exit(ERTS_ERROR_EXIT, "Failed to create dirty io scheduler thread %d\n", ix);
+		erts_exit(ERTS_ERROR_EXIT, "Failed to create dirty io scheduler thread %d, error = %d\n", ix, res);
 	}
     }
-#endif
-#endif
 
     ERTS_THR_MEMORY_BARRIER;
 
     erts_snprintf(opts.name, 16, "aux");
 
-    res = ethr_thr_create(&aux_tid, aux_thread, NULL, &opts);
+    res = ethr_thr_create(&tid, aux_thread, NULL, &opts);
     if (res != 0)
-	erts_exit(ERTS_ERROR_EXIT, "Failed to create aux thread\n");
+	erts_exit(ERTS_ERROR_EXIT, "Failed to create aux thread, error = %d\n", res);
+
+    for (ix = 0; ix < erts_no_poll_threads; ix++) {
+        erts_snprintf(opts.name, 16, "%d_poller", ix);
+
+        res = ethr_thr_create(&tid, poll_thread, (void*)(UWord)ix, &opts);
+        if (res != 0)
+            erts_exit(ERTS_ERROR_EXIT, "Failed to create poll thread\n");
+    }
 
     if (actual < 1)
 	erts_exit(ERTS_ERROR_EXIT,
@@ -9103,9 +8518,7 @@ erts_start_schedulers(void)
     }
 }
 
-#endif /* ERTS_SMP */
 
-#ifdef ERTS_SMP
 
 static void
 add_pend_suspend(Process *suspendee,
@@ -9141,7 +8554,7 @@ handle_pending_suspend(Process *p, ErtsProcLocks p_locks)
     ErtsPendingSuspend *psp;
     int is_alive = !ERTS_PROC_IS_EXITING(p);
 
-    ERTS_SMP_LC_ASSERT(p_locks & ERTS_PROC_LOCK_STATUS);
+    ERTS_LC_ASSERT(p_locks & ERTS_PROC_LOCK_STATUS);
 
     /*
      * New pending suspenders might appear while we are processing
@@ -9167,15 +8580,15 @@ cancel_suspend_of_suspendee(Process *p, ErtsProcLocks p_locks)
     if (is_not_nil(p->suspendee)) {
 	Process *rp;
 	if (!(p_locks & ERTS_PROC_LOCK_STATUS))
-	    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
 	rp = erts_pid2proc(p, p_locks|ERTS_PROC_LOCK_STATUS,
 			   p->suspendee, ERTS_PROC_LOCK_STATUS);
 	if (rp) {
 	    erts_resume(rp, ERTS_PROC_LOCK_STATUS);
-	    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
 	}
 	if (!(p_locks & ERTS_PROC_LOCK_STATUS))
-	    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
 	p->suspendee = NIL;
     }
 }
@@ -9188,7 +8601,7 @@ handle_pend_sync_suspend(Process *suspendee,
 {
     Process *suspender;
 
-    ERTS_SMP_LC_ASSERT(suspendee_locks & ERTS_PROC_LOCK_STATUS);
+    ERTS_LC_ASSERT(suspendee_locks & ERTS_PROC_LOCK_STATUS);
 
     suspender = erts_pid2proc(suspendee,
 			      suspendee_locks,
@@ -9204,7 +8617,7 @@ handle_pend_sync_suspend(Process *suspendee,
 	   resume suspender */
 	ASSERT(suspendee != suspender);
 	resume_process(suspender, ERTS_PROC_LOCK_STATUS);
-	erts_smp_proc_unlock(suspender, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(suspender, ERTS_PROC_LOCK_STATUS);
     }
 }
 
@@ -9215,10 +8628,10 @@ pid2proc_not_running(Process *c_p, ErtsProcLocks c_p_locks,
     Process *rp;
     int unlock_c_p_status;
 
-    ERTS_SMP_LC_ASSERT(c_p_locks == erts_proc_lc_my_proc_locks(c_p));
+    ERTS_LC_ASSERT(c_p_locks == erts_proc_lc_my_proc_locks(c_p));
 
-    ERTS_SMP_LC_ASSERT(c_p_locks & ERTS_PROC_LOCK_MAIN);
-    ERTS_SMP_LC_ASSERT(pid_locks & (ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_STATUS));
+    ERTS_LC_ASSERT(c_p_locks & ERTS_PROC_LOCK_MAIN);
+    ERTS_LC_ASSERT(pid_locks & (ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_STATUS));
 
     if (c_p->common.id == pid)
 	return erts_pid2proc(c_p, c_p_locks, pid, pid_locks);
@@ -9227,7 +8640,7 @@ pid2proc_not_running(Process *c_p, ErtsProcLocks c_p_locks,
 	unlock_c_p_status = 0;
     else {
 	unlock_c_p_status = 1;
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_lock(c_p, ERTS_PROC_LOCK_STATUS);
     }
 
     if (c_p->suspendee == pid) {
@@ -9266,21 +8679,19 @@ pid2proc_not_running(Process *c_p, ErtsProcLocks c_p_locks,
 	    /* Other process running */
 
 	    ASSERT((ERTS_PSFLG_RUNNING | ERTS_PSFLG_DIRTY_RUNNING)
-		   & erts_smp_atomic32_read_nob(&rp->state));
+		   & erts_atomic32_read_nob(&rp->state));
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 	    if (!suspend
-		&& (erts_smp_atomic32_read_nob(&rp->state)
+		&& (erts_atomic32_read_nob(&rp->state)
 		    & ERTS_PSFLG_DIRTY_RUNNING)) {
 		ErtsProcLocks need_locks = pid_locks & ~ERTS_PROC_LOCK_STATUS;
-		if (need_locks && erts_smp_proc_trylock(rp, need_locks) == EBUSY) {
-		    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
+		if (need_locks && erts_proc_trylock(rp, need_locks) == EBUSY) {
+		    erts_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
 		    rp = erts_pid2proc(c_p, c_p_locks|ERTS_PROC_LOCK_STATUS,
 				       pid, pid_locks|ERTS_PROC_LOCK_STATUS);
 		}
 		goto done;
 	    }
-#endif
 
 	running:
 
@@ -9300,19 +8711,19 @@ pid2proc_not_running(Process *c_p, ErtsProcLocks c_p_locks,
 		c_p->flags |= F_P2PNR_RESCHED;
 	    }
 	    /* Yield (caller is assumed to yield immediately in bif). */
-	    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
 	    rp = ERTS_PROC_LOCK_BUSY;
 	}
 	else {
 	    ErtsProcLocks need_locks = pid_locks & ~ERTS_PROC_LOCK_STATUS;
-	    if (need_locks && erts_smp_proc_trylock(rp, need_locks) == EBUSY) {
+	    if (need_locks && erts_proc_trylock(rp, need_locks) == EBUSY) {
 		if ((ERTS_PSFLG_RUNNING_SYS|ERTS_PSFLG_DIRTY_RUNNING_SYS)
-		    & erts_smp_atomic32_read_nob(&rp->state)) {
+		    & erts_atomic32_read_nob(&rp->state)) {
 		    /* Executing system task... */
 		    resume_process(rp, ERTS_PROC_LOCK_STATUS);
 		    goto running;
 		}
-		erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
+		erts_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
 		/*
 		 * If we are unlucky, the process just got selected for
 		 * execution of a system task. In this case we may be
@@ -9336,7 +8747,7 @@ pid2proc_not_running(Process *c_p, ErtsProcLocks c_p_locks,
 #ifdef DEBUG
 	    {
 		erts_aint32_t state;
-		state = erts_smp_atomic32_read_nob(&rp->state);
+		state = erts_atomic32_read_nob(&rp->state);
 		ASSERT((state & ERTS_PSFLG_PENDING_EXIT)
 		       || !(state & ERTS_PSFLG_RUNNING));
 	    }
@@ -9350,9 +8761,9 @@ pid2proc_not_running(Process *c_p, ErtsProcLocks c_p_locks,
  done:
 	
     if (rp && rp != ERTS_PROC_LOCK_BUSY && !(pid_locks & ERTS_PROC_LOCK_STATUS))
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_STATUS);
     if (unlock_c_p_status)
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_STATUS);
     return rp;
 }
 
@@ -9398,7 +8809,7 @@ do_bif_suspend_process(Process *c_p,
 {
     ASSERT(suspendee);
     ASSERT(!ERTS_PROC_IS_EXITING(suspendee));
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_STATUS
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_STATUS
 		       & erts_proc_lc_my_proc_locks(suspendee));
     if (smon) {
 	if (!smon->active) {
@@ -9421,7 +8832,7 @@ handle_pend_bif_sync_suspend(Process *suspendee,
 {
     Process *suspender;
 
-    ERTS_SMP_LC_ASSERT(suspendee_locks & ERTS_PROC_LOCK_STATUS);
+    ERTS_LC_ASSERT(suspendee_locks & ERTS_PROC_LOCK_STATUS);
 
     suspender = erts_pid2proc(suspendee,
 			      suspendee_locks,
@@ -9450,7 +8861,7 @@ handle_pend_bif_sync_suspend(Process *suspendee,
 	   resume suspender */
 	ASSERT(suspender != suspendee);
 	resume_process(suspender, ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
-	erts_smp_proc_unlock(suspender,
+	erts_proc_unlock(suspender,
 			     ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS);
     }
 }
@@ -9464,7 +8875,7 @@ handle_pend_bif_async_suspend(Process *suspendee,
 
     Process *suspender;
 
-    ERTS_SMP_LC_ASSERT(suspendee_locks & ERTS_PROC_LOCK_STATUS);
+    ERTS_LC_ASSERT(suspendee_locks & ERTS_PROC_LOCK_STATUS);
 
     suspender = erts_pid2proc(suspendee,
 			      suspendee_locks,
@@ -9488,11 +8899,10 @@ handle_pend_bif_async_suspend(Process *suspendee,
 	    do_bif_suspend_process(suspendee, smon, suspendee);
 	    ASSERT(!smon || res != 0);
 	}
-	erts_smp_proc_unlock(suspender, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(suspender, ERTS_PROC_LOCK_LINK);
     }
 }
 
-#endif /* ERTS_SMP */
 
 /*
  * The erlang:suspend_process/2 BIF
@@ -9541,7 +8951,7 @@ suspend_process_2(BIF_ALIST_2)
 				    ? (ErtsProcLocks) 0
 				    : ERTS_PROC_LOCK_STATUS);
 
-    erts_smp_proc_lock(BIF_P, xlocks);
+    erts_proc_lock(BIF_P, xlocks);
 
     suspendee = erts_pid2proc(BIF_P,
 			      ERTS_PROC_LOCK_MAIN|xlocks,
@@ -9552,34 +8962,15 @@ suspend_process_2(BIF_ALIST_2)
 
     smon = erts_add_or_lookup_suspend_monitor(&BIF_P->suspend_monitors,
 					      BIF_ARG_1);
-#ifndef ERTS_SMP /* no ERTS_SMP */
-
-    /* This is really a piece of cake without SMP support... */
-    if (!smon->active) {
-	erts_smp_atomic32_read_bor_nob(&suspendee->state, ERTS_PSFLG_SUSPENDED);
-	suspend_process(BIF_P, suspendee);
-	smon->active++;
-	res = am_true;
-    }
-    else if (unless_suspending)
-	res = am_false;
-    else if (smon->active == INT_MAX)
-	goto system_limit;
-    else {
-	smon->active++;
-	res = am_true;
-    }
-
-#else /* ERTS_SMP */
 
     /* ... but a little trickier with SMP support ... */
 
     if (asynchronous) {
 	/* --- Asynchronous suspend begin ---------------------------------- */
 
-	ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_LINK
+	ERTS_LC_ASSERT(ERTS_PROC_LOCK_LINK
 			   & erts_proc_lc_my_proc_locks(BIF_P));
-	ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_STATUS
+	ERTS_LC_ASSERT(ERTS_PROC_LOCK_STATUS
 			   == erts_proc_lc_my_proc_locks(suspendee));
 
 	if (smon->active) {
@@ -9619,10 +9010,10 @@ suspend_process_2(BIF_ALIST_2)
     else /* if (!asynchronous) */ {
 	/* --- Synchronous suspend begin ----------------------------------- */
 
-	ERTS_SMP_LC_ASSERT(((ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS)
+	ERTS_LC_ASSERT(((ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS)
 			    & erts_proc_lc_my_proc_locks(BIF_P))
 			   == (ERTS_PROC_LOCK_LINK|ERTS_PROC_LOCK_STATUS));
-	ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_STATUS
+	ERTS_LC_ASSERT(ERTS_PROC_LOCK_STATUS
 			   == erts_proc_lc_my_proc_locks(suspendee));
 
 	if (BIF_P->suspendee == BIF_ARG_1) {
@@ -9688,10 +9079,9 @@ suspend_process_2(BIF_ALIST_2)
 	/* --- Synchronous suspend end ------------------------------------- */
     }
 
-#endif /* ERTS_SMP */
 #ifdef DEBUG
     {
-	erts_aint32_t state = erts_smp_atomic32_read_acqb(&suspendee->state);
+	erts_aint32_t state = erts_atomic32_read_acqb(&suspendee->state);
 	ASSERT((state & ERTS_PSFLG_SUSPENDED)
 	       || (asynchronous && smon->pending));
 	ASSERT((state & ERTS_PSFLG_SUSPENDED)
@@ -9699,8 +9089,8 @@ suspend_process_2(BIF_ALIST_2)
     }
 #endif
 
-    erts_smp_proc_unlock(suspendee, ERTS_PROC_LOCK_STATUS);
-    erts_smp_proc_unlock(BIF_P, xlocks);
+    erts_proc_unlock(suspendee, ERTS_PROC_LOCK_STATUS);
+    erts_proc_unlock(BIF_P, xlocks);
     BIF_RET(res);
 
  system_limit:
@@ -9708,26 +9098,22 @@ suspend_process_2(BIF_ALIST_2)
     goto do_return;
 
  no_suspendee:
-#ifdef ERTS_SMP
     BIF_P->suspendee = NIL;
-#endif
     erts_delete_suspend_monitor(&BIF_P->suspend_monitors, BIF_ARG_1);
 
  badarg:
     ERTS_BIF_PREP_ERROR(res, BIF_P, BADARG);
-#ifdef ERTS_SMP
     goto do_return;
 
  yield:
     ERTS_BIF_PREP_YIELD2(res, bif_export[BIF_suspend_process_2],
 			 BIF_P, BIF_ARG_1, BIF_ARG_2);
-#endif
 
  do_return:
     if (suspendee)
-	erts_smp_proc_unlock(suspendee, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(suspendee, ERTS_PROC_LOCK_STATUS);
     if (xlocks)
-	erts_smp_proc_unlock(BIF_P, xlocks);
+	erts_proc_unlock(BIF_P, xlocks);
     return res;
 
 }
@@ -9747,7 +9133,7 @@ resume_process_1(BIF_ALIST_1)
     if (BIF_P->common.id == BIF_ARG_1)
 	BIF_ERROR(BIF_P, BADARG);
 
-    erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK);
+    erts_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK);
     smon = erts_lookup_suspend_monitor(BIF_P->suspend_monitors, BIF_ARG_1);
 
     if (!smon) {
@@ -9793,17 +9179,17 @@ resume_process_1(BIF_ALIST_1)
 	    goto no_suspendee;
 
 	ASSERT(ERTS_PSFLG_SUSPENDED
-	       & erts_smp_atomic32_read_nob(&suspendee->state));
+	       & erts_atomic32_read_nob(&suspendee->state));
 	ASSERT(BIF_P != suspendee);
 	resume_process(suspendee, ERTS_PROC_LOCK_STATUS);
 
-	erts_smp_proc_unlock(suspendee, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(suspendee, ERTS_PROC_LOCK_STATUS);
     }
 
     if (!smon->active && !smon->pending)
 	erts_delete_suspend_monitor(&BIF_P->suspend_monitors, BIF_ARG_1);
 
-    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
+    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
 
     BIF_RET(am_true);
 
@@ -9812,7 +9198,7 @@ resume_process_1(BIF_ALIST_1)
     erts_delete_suspend_monitor(&BIF_P->suspend_monitors, BIF_ARG_1);
 
  error:
-    erts_smp_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
+    erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_LINK);
     BIF_ERROR(BIF_P, BADARG);
 }
 
@@ -9821,18 +9207,16 @@ erts_internal_is_process_executing_dirty_1(BIF_ALIST_1)
 {
     if (is_not_internal_pid(BIF_ARG_1))
 	BIF_ERROR(BIF_P, BADARG);
-#ifdef ERTS_DIRTY_SCHEDULERS
     else {
 	Process *rp = erts_proc_lookup(BIF_ARG_1);
 	if (rp) {
-	    erts_aint32_t state = erts_smp_atomic32_read_nob(&rp->state);
+	    erts_aint32_t state = erts_atomic32_read_nob(&rp->state);
 	    if (state & (ERTS_PSFLG_DIRTY_RUNNING
 			 |ERTS_PSFLG_DIRTY_RUNNING_SYS)) {
 		BIF_RET(am_true);
 	    }
 	}
     }
-#endif
     BIF_RET(am_false);
 }
 
@@ -9842,28 +9226,26 @@ run_queues_len_aux(ErtsRunQueue *rq, Uint *tot_len, Uint *qlen, int *ip, int inc
     Sint rq_len;
 
     if (locked)
-        rq_len = (Sint) erts_smp_atomic32_read_dirty(&rq->len);
+        rq_len = (Sint) erts_atomic32_read_dirty(&rq->len);
     else
-        rq_len = (Sint) erts_smp_atomic32_read_nob(&rq->len);
+        rq_len = (Sint) erts_atomic32_read_nob(&rq->len);
     ASSERT(rq_len >= 0);
 
     if (incl_active_sched) {
-#ifdef ERTS_DIRTY_SCHEDULERS
         if (ERTS_RUNQ_IX_IS_DIRTY(rq->ix)) {
             erts_aint32_t dcnt;
             if (ERTS_RUNQ_IS_DIRTY_CPU_RUNQ(rq)) {
-                dcnt = erts_smp_atomic32_read_nob(&dirty_count.cpu.active);
+                dcnt = erts_atomic32_read_nob(&dirty_count.cpu.active);
                 ASSERT(0 <= dcnt && dcnt <= erts_no_dirty_cpu_schedulers);
             }
             else {
                 ASSERT(ERTS_RUNQ_IS_DIRTY_IO_RUNQ(rq));
-                dcnt = erts_smp_atomic32_read_nob(&dirty_count.io.active);
+                dcnt = erts_atomic32_read_nob(&dirty_count.io.active);
                 ASSERT(0 <= dcnt && dcnt <= erts_no_dirty_io_schedulers);
             }
             rq_len += (Sint) dcnt;
         }
         else
-#endif
         {
             if (ERTS_RUNQ_FLGS_GET_NOB(rq) & ERTS_RUNQ_FLG_EXEC)
                 rq_len++;
@@ -9882,12 +9264,10 @@ erts_run_queues_len(Uint *qlen, int atomic_queues_read, int incl_active_sched,
     Uint len = 0;
     int no_rqs = erts_no_run_queues;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (incl_dirty_io)
         no_rqs += ERTS_NUM_DIRTY_RUNQS;
     else
         no_rqs += ERTS_NUM_DIRTY_CPU_RUNQS;
-#endif
 
     if (atomic_queues_read) {
         ERTS_ATOMIC_FOREACH_RUNQ_X(rq, no_rqs,
@@ -9941,27 +9321,25 @@ erts_process_status(Process *rp, Eterm rpid)
     Process *p = rp ? rp : erts_proc_lookup_raw(rpid);
 
     if (p) {
-	erts_aint32_t state = erts_smp_atomic32_read_acqb(&p->state);
+	erts_aint32_t state = erts_atomic32_read_acqb(&p->state);
 	res = erts_process_state2status(state);
     }
-#ifdef ERTS_SMP
     else {
 	int i;
 	ErtsSchedulerData *esdp;
 
 	for (i = 0; i < erts_no_schedulers; i++) {
 	    esdp = ERTS_SCHEDULER_IX(i);
-	    erts_smp_runq_lock(esdp->run_queue);
+	    erts_runq_lock(esdp->run_queue);
 	    if (esdp->free_process
 		&& esdp->free_process->common.id == rpid) {
 		res = am_free;
-		erts_smp_runq_unlock(esdp->run_queue);
+		erts_runq_unlock(esdp->run_queue);
 		break;
 	    }
-	    erts_smp_runq_unlock(esdp->run_queue);
+	    erts_runq_unlock(esdp->run_queue);
 	}
     }
-#endif
     return res;
 }
 
@@ -9977,9 +9355,9 @@ erts_suspend(Process* c_p, ErtsProcLocks c_p_locks, Port *busy_port)
     int suspend;
 
     ASSERT(c_p == erts_get_current_process());
-    ERTS_SMP_LC_ASSERT(c_p_locks == erts_proc_lc_my_proc_locks(c_p));
+    ERTS_LC_ASSERT(c_p_locks == erts_proc_lc_my_proc_locks(c_p));
     if (!(c_p_locks & ERTS_PROC_LOCK_STATUS))
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_lock(c_p, ERTS_PROC_LOCK_STATUS);
 
     if (busy_port)
 	suspend = erts_save_suspend_process_on_port(busy_port, c_p);
@@ -9995,7 +9373,7 @@ erts_suspend(Process* c_p, ErtsProcLocks c_p_locks, Port *busy_port)
     }
 
     if (!(c_p_locks & ERTS_PROC_LOCK_STATUS))
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_STATUS);
 
     if (suspend && busy_port && erts_system_monitor_flags.busy_port)
 	monitor_generic(c_p, am_busy_port, busy_port->common.id);
@@ -10004,12 +9382,12 @@ erts_suspend(Process* c_p, ErtsProcLocks c_p_locks, Port *busy_port)
 void
 erts_resume(Process* process, ErtsProcLocks process_locks)
 {
-    ERTS_SMP_LC_ASSERT(process_locks == erts_proc_lc_my_proc_locks(process));
+    ERTS_LC_ASSERT(process_locks == erts_proc_lc_my_proc_locks(process));
     if (!(process_locks & ERTS_PROC_LOCK_STATUS))
-	erts_smp_proc_lock(process, ERTS_PROC_LOCK_STATUS);
+	erts_proc_lock(process, ERTS_PROC_LOCK_STATUS);
     resume_process(process, process_locks|ERTS_PROC_LOCK_STATUS);
     if (!(process_locks & ERTS_PROC_LOCK_STATUS))
-	erts_smp_proc_unlock(process, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(process, ERTS_PROC_LOCK_STATUS);
 }
 
 int
@@ -10029,7 +9407,7 @@ erts_resume_processes(ErtsProcList *list)
 		resume_process(proc, ERTS_PROC_LOCK_STATUS);
 		nresumed++;
 	    }
-	    erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_unlock(proc, ERTS_PROC_LOCK_STATUS);
 	}
 	fplp = plp;
 	plp = plp->next;
@@ -10041,7 +9419,7 @@ erts_resume_processes(ErtsProcList *list)
 Eterm
 erts_get_process_priority(Process *p)
 {
-    erts_aint32_t state = erts_smp_atomic32_read_nob(&p->state);
+    erts_aint32_t state = erts_atomic32_read_nob(&p->state);
     switch (ERTS_PSFLGS_GET_USR_PRIO(state)) {
     case PRIORITY_MAX:		return am_max;
     case PRIORITY_HIGH:		return am_high;
@@ -10064,7 +9442,7 @@ erts_set_process_priority(Process *p, Eterm value)
     default:		return THE_NON_VALUE;				break;
     }
 
-    a = erts_smp_atomic32_read_nob(&p->state);
+    a = erts_atomic32_read_nob(&p->state);
     if (nprio == ERTS_PSFLGS_GET_USR_PRIO(a))
 	oprio = nprio;
     else {
@@ -10072,7 +9450,7 @@ erts_set_process_priority(Process *p, Eterm value)
 	erts_aint32_t e, n, aprio;
 
 	if (a & ERTS_PSFLG_ACTIVE_SYS) {
-	    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+	    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
 	    slocked = 1;
 	}
 
@@ -10086,7 +9464,7 @@ erts_set_process_priority(Process *p, Eterm value)
 		int max_qbit;
 
 		if (!slocked) {
-		    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+		    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
 		    slocked = 1;
 		}
 
@@ -10127,11 +9505,11 @@ erts_set_process_priority(Process *p, Eterm value)
 	    n |= ((nprio << ERTS_PSFLGS_USR_PRIO_OFFSET)
 		  | (aprio << ERTS_PSFLGS_ACT_PRIO_OFFSET));
 
-	    a = erts_smp_atomic32_cmpxchg_mb(&p->state, n, e);
+	    a = erts_atomic32_cmpxchg_mb(&p->state, n, e);
 	} while (a != e);
 
         if (slocked)
-            erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+            erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
 
     }
 
@@ -10189,7 +9567,6 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
     ErtsRunQueue *rq;
     int context_reds;
     int fcalls;
-    int input_reductions;
     int actual_reds;
     int reds;
     Uint32 flags;
@@ -10209,21 +9586,18 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 
     if (ERTS_USE_MODIFIED_TIMING()) {
 	context_reds = ERTS_MODIFIED_TIMING_CONTEXT_REDS;
-	input_reductions = ERTS_MODIFIED_TIMING_INPUT_REDS;
     }
     else {
 	context_reds = CONTEXT_REDS;
-	input_reductions = INPUT_REDUCTIONS;
     }
 
-    ERTS_SMP_LC_ASSERT(ERTS_SCHEDULER_IS_DIRTY(erts_get_scheduler_data())
+    ERTS_LC_ASSERT(ERTS_SCHEDULER_IS_DIRTY(erts_get_scheduler_data())
 		       || !erts_thr_progress_is_blocking());
 
     /*
      * Clean up after the process being scheduled out.
      */
     if (!p) {	/* NULL in the very first schedule() call */
-#ifdef ERTS_DIRTY_SCHEDULERS
 	is_normal_sched = !esdp;
 	if (is_normal_sched) {
 	    esdp = erts_get_scheduler_data();
@@ -10232,18 +9606,11 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 	else {
 	    ASSERT(ERTS_SCHEDULER_IS_DIRTY(esdp));
 	}
-#else
-	esdp = erts_get_scheduler_data();
-	is_normal_sched = 1;
-#endif
 	rq = erts_get_runq_current(esdp);
 	ASSERT(esdp);
-	fcalls = (int) erts_smp_atomic32_read_acqb(&function_calls);
 	actual_reds = reds = 0;
-	erts_smp_runq_lock(rq);
+	erts_runq_lock(rq);
     } else {
-#ifdef ERTS_SMP
-#ifdef ERTS_DIRTY_SCHEDULERS
 	is_normal_sched = !esdp;
 	if (is_normal_sched) {
 	    esdp = p->scheduler_data;
@@ -10252,21 +9619,12 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 	else {
 	    ASSERT(ERTS_SCHEDULER_IS_DIRTY(esdp));
 	}
-#else
-	esdp = p->scheduler_data;
-	is_normal_sched = 1;
-#endif
 	ASSERT(esdp->current_process == p
 	       || esdp->free_process == p);
-#else
-	esdp = erts_scheduler_data;
-	ASSERT(esdp->current_process == p);
-	is_normal_sched = 1;
-#endif
 
     sched_out_proc:
 
-	ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
+	ERTS_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
 
 	reds = actual_reds = calls - esdp->virtual_reds;
 
@@ -10275,14 +9633,13 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 	    reds = ERTS_PROC_MIN_CONTEXT_SWITCH_REDS_COST;
 	esdp->virtual_reds = 0;
 
-	fcalls = (int) erts_smp_atomic32_add_read_acqb(&function_calls, reds);
 	ASSERT(esdp && esdp == erts_get_scheduler_data());
 
 	rq = erts_get_runq_current(esdp);
 
 	p->reds += actual_reds;
 
-	state = erts_smp_atomic32_read_nob(&p->state);
+	state = erts_atomic32_read_nob(&p->state);
 
 	if (IS_TRACED(p)) {
 	    if (IS_TRACED_FL(p, F_TRACE_CALLS) && !(state & ERTS_PSFLG_FREE))
@@ -10301,20 +9658,17 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 	    }
 	}
 
-	erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
+	erts_proc_lock(p, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
 
-#ifdef ERTS_SMP
         if (p->trace_msg_q) {
-	    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
+	    erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
             erts_schedule_flush_trace_messages(p, 1);
-	    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
+	    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
 	}
-#endif
 
         /* have to re-read state after taking lock */
-        state = erts_smp_atomic32_read_nob(&p->state);
+        state = erts_atomic32_read_nob(&p->state);
 
-#ifdef ERTS_SMP
 	if (is_normal_sched && (state & ERTS_PSFLG_PENDING_EXIT))
 	    erts_handle_pending_exit(p, (ERTS_PROC_LOCK_MAIN
 					 | ERTS_PROC_LOCK_TRACE
@@ -10323,7 +9677,6 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 	    handle_pending_suspend(p, (ERTS_PROC_LOCK_MAIN
 				       | ERTS_PROC_LOCK_TRACE
 				       | ERTS_PROC_LOCK_STATUS));
-#endif
 
 	esdp->reductions += reds;
 
@@ -10341,18 +9694,15 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
                                           actual_reds);
 
             esdp->current_process = NULL;
-#ifdef ERTS_SMP
             if (is_normal_sched)
                 p->scheduler_data = NULL;
-#endif
 
-            erts_smp_proc_unlock(p, (ERTS_PROC_LOCK_MAIN
+            erts_proc_unlock(p, (ERTS_PROC_LOCK_MAIN
                                      | ERTS_PROC_LOCK_STATUS
                                      | ERTS_PROC_LOCK_TRACE));
 
             ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_OTHER);
 
-#ifdef ERTS_SMP
             if (state & ERTS_PSFLG_FREE) {
                 if (!is_normal_sched) {
                     ASSERT(p->flags & F_DELAYED_DEL_PROC);
@@ -10362,44 +9712,40 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
                     esdp->free_process = NULL;
                 }
             }
-#endif
 
             if (dec_refc)
                 erts_proc_dec_refc(p);
         }
 
-#ifdef ERTS_SMP
 	ASSERT(!esdp->free_process);
-#endif
 	ASSERT(!esdp->current_process);
 
-	ERTS_SMP_CHK_NO_PROC_LOCKS;
+	ERTS_CHK_NO_PROC_LOCKS;
 
-	if (is_normal_sched) {
-	    if (esdp->check_time_reds >= ERTS_CHECK_TIME_REDS)
-		(void) erts_get_monotonic_time(esdp);
-
-	    if (esdp->last_monotonic_time >= erts_next_timeout_time(esdp->next_tmo_ref)) {
-		erts_smp_runq_unlock(rq);
-		erts_bump_timers(esdp->timer_wheel, esdp->last_monotonic_time);
-		erts_smp_runq_lock(rq);
-	    }
-	}
     }
 
-    ERTS_SMP_LC_ASSERT(!is_normal_sched || !erts_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(!is_normal_sched || !erts_thr_progress_is_blocking());
 
  check_activities_to_run: {
 	erts_aint32_t psflg_running, psflg_running_sys;
-#ifdef ERTS_SMP
 	ErtsMigrationPaths *mps;
 	ErtsMigrationPath *mp;
 
 	if (is_normal_sched) {
+
+	    if (esdp->check_time_reds >= ERTS_CHECK_TIME_REDS)
+		(void) erts_get_monotonic_time(esdp);
+
+	    if (esdp->last_monotonic_time >= erts_next_timeout_time(esdp->next_tmo_ref)) {
+		erts_runq_unlock(rq);
+		erts_bump_timers(esdp->timer_wheel, esdp->last_monotonic_time);
+		erts_runq_lock(rq);
+	    }
+
 	    if (rq->check_balance_reds <= 0)
 		check_balance(rq);
 
-	    ERTS_SMP_LC_ASSERT(!erts_thr_progress_is_blocking());
+	    ERTS_LC_ASSERT(!erts_thr_progress_is_blocking());
 
 	    mps = erts_get_migration_paths_managed();
 	    mp = &mps->mpath[rq->ix];
@@ -10408,14 +9754,14 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 		immigrate(rq, mp);
 	}
 
-	ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+	ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
     continue_check_activities_to_run:
 	flags = ERTS_RUNQ_FLGS_GET_NOB(rq);
     continue_check_activities_to_run_known_flags:
 	ASSERT(!is_normal_sched || (flags & ERTS_RUNQ_FLG_NONEMPTY));
 
 	if (!is_normal_sched) {
-	    if (erts_smp_atomic32_read_acqb(&esdp->ssi->flags)
+	    if (erts_atomic32_read_acqb(&esdp->ssi->flags)
 		& (ERTS_SSI_FLG_SUSPENDED|ERTS_SSI_FLG_MSB_EXEC)) {
 		suspend_scheduler(esdp);
 	    }
@@ -10445,26 +9791,18 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 	    leader_update = erts_thr_progress_update(esdp);
 	    aux_work = erts_atomic32_read_acqb(&esdp->ssi->aux_work);
 	    if (aux_work | leader_update) {
-		erts_smp_runq_unlock(rq);
+		erts_runq_unlock(rq);
 		if (leader_update)
 		    erts_thr_progress_leader_update(esdp);
 		if (aux_work)
 		    handle_aux_work(&esdp->aux_work_data, aux_work, 0);
-		erts_smp_runq_lock(rq);
+		erts_runq_lock(rq);
 	    }
 
-	    ERTS_SMP_LC_ASSERT(!erts_thr_progress_is_blocking());
+	    ERTS_LC_ASSERT(!erts_thr_progress_is_blocking());
 	}
-	ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+	ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
 
-#else /* ERTS_SMP */
-	{
-	    erts_aint32_t aux_work;
-	    aux_work = erts_atomic32_read_acqb(&esdp->ssi->aux_work);
-	    if (aux_work)
-		handle_aux_work(&esdp->aux_work_data, aux_work, 0);
-	}
-#endif /* ERTS_SMP */
 
 	flags = ERTS_RUNQ_FLGS_GET_NOB(rq);
 
@@ -10475,8 +9813,7 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 	}
 	else if (!runq_got_work_to_execute_flags(flags)) {
 	    /* Prepare for scheduler wait */
-#ifdef ERTS_SMP
-	    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+	    ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
 
 	    rq->wakeup_other = 0;
 	    rq->wakeup_other_reds = 0;
@@ -10490,7 +9827,7 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
                 ASSERT(!runq_got_work_to_execute(rq));
 		if (!is_normal_sched) {
                     /* Dirty scheduler */
-                    if (erts_smp_atomic32_read_acqb(&esdp->ssi->flags)
+                    if (erts_atomic32_read_acqb(&esdp->ssi->flags)
                         & (ERTS_SSI_FLG_SUSPENDED|ERTS_SSI_FLG_MSB_EXEC)) {
                         /* Go suspend... */
                         goto continue_check_activities_to_run_known_flags;
@@ -10506,7 +9843,6 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
                      */
                     flags = ERTS_RUNQ_FLGS_GET_NOB(rq);
                     if ((flags & ERTS_RUNQ_FLG_SUSPENDED)
-#ifdef ERTS_DIRTY_SCHEDULERS
                         /* If multi scheduling block and we have
                          * dirty work, suspend and let dirty
                          * scheduler handle work... */
@@ -10514,7 +9850,6 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
                                        | ERTS_RUNQ_FLG_MSB_EXEC))
                               == ERTS_RUNQ_FLG_MSB_EXEC))
                             && have_dirty_work())
-#endif
                         ) {
                         non_empty_runq(rq);
                         flags |= ERTS_RUNQ_FLG_NONEMPTY;
@@ -10526,62 +9861,21 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 		}
 		empty_runq(rq);
 	    }
-#endif
 
 	    (void) ERTS_RUNQ_FLGS_UNSET(rq, ERTS_RUNQ_FLG_EXEC);
 	    scheduler_wait(&fcalls, esdp, rq);
 	    flags = ERTS_RUNQ_FLGS_SET_NOB(rq, ERTS_RUNQ_FLG_EXEC);
 	    flags |= ERTS_RUNQ_FLG_EXEC;
             ERTS_MSACC_UPDATE_CACHE();
-#ifdef ERTS_SMP
 	    non_empty_runq(rq);
-#endif
-
-	    goto check_activities_to_run;
-	}
-	else if (is_normal_sched
-		 && (fcalls > input_reductions
-		     && prepare_for_sys_schedule(!0))) {
-	    ErtsMonotonicTime current_time;
-	    /*
-	     * Schedule system-level activities.
-	     */
-
-	    ERTS_MSACC_PUSH_STATE_CACHED_M();
-
-	    erts_smp_atomic32_set_relb(&function_calls, 0);
-	    fcalls = 0;
-
-#if 0 /* Not needed since we wont wait in sys schedule */
-	    erts_sys_schedule_interrupt(0);
-#endif
-	    erts_smp_runq_unlock(rq);
-
-            ERTS_MSACC_SET_STATE_CACHED_M(ERTS_MSACC_STATE_CHECK_IO);
-            LTTNG2(scheduler_poll, esdp->no, 1);
-
-	    erl_sys_schedule(1);
-	    ERTS_MSACC_POP_STATE_M();
 
-	    current_time = erts_get_monotonic_time(esdp);
-	    if (current_time >= erts_next_timeout_time(esdp->next_tmo_ref))
-		erts_bump_timers(esdp->timer_wheel, current_time);
-
-#ifdef ERTS_SMP
-	    erts_smp_runq_lock(rq);
-	    clear_sys_scheduling();
-	    goto continue_check_activities_to_run;
-#else
 	    goto check_activities_to_run;
-#endif
 	}
 
         if (flags & ERTS_RUNQ_FLG_MISC_OP)
 	    exec_misc_ops(rq);
 
-#ifdef ERTS_SMP
 	wakeup_other.check(rq, flags);
-#endif
 
 	/*
 	 * Find a new port to run.
@@ -10590,29 +9884,9 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
         flags = ERTS_RUNQ_FLGS_GET_NOB(rq);
 
 	if (flags & PORT_BIT) {
-	    int have_outstanding_io;
-	    have_outstanding_io = erts_port_task_execute(rq, &esdp->current_port);
-	    if ((!erts_eager_check_io
-		 && have_outstanding_io
-		 && fcalls > 2*input_reductions)
-		|| (flags & ERTS_RUNQ_FLG_HALTING)) {
-		/*
-		 * If we have performed more than 2*INPUT_REDUCTIONS since
-		 * last call to erl_sys_schedule() and we still haven't
-		 * handled all I/O tasks we stop running processes and
-		 * focus completely on ports.
-		 *
-		 * One could argue that this is a strange behavior. The
-		 * reason for doing it this way is that it is similar
-		 * to the behavior before port tasks were introduced.
-		 * We don't want to change the behavior too much, at
-		 * least not at the time of writing. This behavior
-		 * might change in the future.
-		 *
-		 * /rickard
-		 */
-		goto check_activities_to_run;
-	    }
+	    erts_port_task_execute(rq, &esdp->current_port);
+            if (flags & ERTS_RUNQ_FLG_HALTING)
+                goto check_activities_to_run;
 	}
 
 	/*
@@ -10679,13 +9953,11 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 		    proxy_p = NULL;
 		    goto pick_next_process;
 		}
-		state = erts_smp_atomic32_read_nob(&p->state);
+		state = erts_atomic32_read_nob(&p->state);
 	    }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 	    if (!is_normal_sched)
 		clear_proc_dirty_queue_bit(p, rq, qbit);
-#endif
 
 	    while (1) {
 		erts_aint32_t exp, new;
@@ -10703,7 +9975,6 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 					    | ERTS_PSFLG_DIRTY_RUNNING
 					    | ERTS_PSFLG_DIRTY_RUNNING_SYS
 					    | ERTS_PSFLG_FREE)))
-#ifdef ERTS_DIRTY_SCHEDULERS
 				| (((state & (ERTS_PSFLG_RUNNING
 
 					      | ERTS_PSFLG_FREE
@@ -10712,7 +9983,6 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 					      | ERTS_PSFLG_EXITING))
 				    == ERTS_PSFLG_EXITING)
 				   & (!!is_normal_sched))
-#endif
 				   )
 			       & ((state & (ERTS_PSFLG_SUSPENDED
 					    | ERTS_PSFLG_EXITING
@@ -10721,11 +9991,9 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 					    | ERTS_PSFLG_ACTIVE_SYS
 					    | ERTS_PSFLG_DIRTY_ACTIVE_SYS))
 				  != ERTS_PSFLG_SUSPENDED)
-#ifdef ERTS_DIRTY_SCHEDULERS
                                & (!(state & (ERTS_PSFLG_EXITING
                                              | ERTS_PSFLG_PENDING_EXIT))
                                   | (!!is_normal_sched))
-#endif
                     );
 
 		if (run_process) {
@@ -10735,7 +10003,7 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 		    else
 			new |= psflg_running;
 		}
-		state = erts_smp_atomic32_cmpxchg_relb(&p->state, new, exp);
+		state = erts_atomic32_cmpxchg_relb(&p->state, new, exp);
 		if (state == exp) {
 		    if (!run_process) {
 			if (proxy_p) {
@@ -10762,22 +10030,21 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 	    calls = 0;
 	    reds = context_reds;
 
-	    erts_smp_runq_unlock(rq);
+	    erts_runq_unlock(rq);
 
 	}
 
         ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_EMULATOR);
 
-#ifdef ERTS_SMP
 
 	if (flags & ERTS_RUNQ_FLG_PROTECTED)
 	    (void) ERTS_RUNQ_FLGS_UNSET(rq, ERTS_RUNQ_FLG_PROTECTED);
 
-	ERTS_SMP_CHK_NO_PROC_LOCKS;
+	ERTS_CHK_NO_PROC_LOCKS;
 
-	erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_STATUS);
+	erts_proc_lock(p, ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_STATUS);
 
-	state = erts_smp_atomic32_read_nob(&p->state);
+	state = erts_atomic32_read_nob(&p->state);
 
 	if (erts_sched_stat.enabled) {
 	    int prio;
@@ -10788,28 +10055,24 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 
 	    prio = (int) ERTS_PSFLGS_GET_USR_PRIO(state);
 
-	    erts_smp_spin_lock(&erts_sched_stat.lock);
+	    erts_spin_lock(&erts_sched_stat.lock);
 	    erts_sched_stat.prio[prio].total_executed++;
 	    erts_sched_stat.prio[prio].executed++;
 	    if (migrated) {
 		erts_sched_stat.prio[prio].total_migrated++;
 		erts_sched_stat.prio[prio].migrated++;
 	    }
-	    erts_smp_spin_unlock(&erts_sched_stat.lock);
+	    erts_spin_unlock(&erts_sched_stat.lock);
 	}
 
-	state = erts_smp_atomic32_read_nob(&p->state);
+	state = erts_atomic32_read_nob(&p->state);
 
-#ifndef ERTS_DIRTY_SCHEDULERS
-	ASSERT(!p->scheduler_data);
-	p->scheduler_data = esdp;
-#else /* ERTS_DIRTY_SCHEDULERS */
 	if (is_normal_sched) {
 	    if ((!!(state & ERTS_PSFLGS_DIRTY_WORK))
 		& (!(state & ERTS_PSFLG_ACTIVE_SYS))) {
 		/* Migrate to dirty scheduler... */
 	    sunlock_sched_out_proc:
-		erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+		erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
 		goto sched_out_proc;
 	    }
 	    ASSERT(!p->scheduler_data);
@@ -10839,17 +10102,15 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 		   : (rq == ERTS_DIRTY_IO_RUNQ
 		      && (state & ERTS_PSFLG_DIRTY_IO_PROC)));	    
 	}
-#endif
 
 	if (state & ERTS_PSFLG_PENDING_EXIT) {
 	    erts_handle_pending_exit(p,
 				     ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_STATUS);
-	    state = erts_smp_atomic32_read_nob(&p->state);
+	    state = erts_atomic32_read_nob(&p->state);
 	}
 
-#endif /* ERTS_SMP */
 
-	erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
 
         /* Clear tracer if it has been removed */
 	if (IS_TRACED(p) && erts_is_tracer_proc_enabled(
@@ -10885,10 +10146,8 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
                     reds -= cost;
                     if (reds <= 0)
                         goto sched_out_proc;
-#ifdef ERTS_DIRTY_SCHEDULERS
                     if (state & ERTS_PSFLGS_DIRTY_WORK)
                         goto sched_out_proc;
-#endif
                 }
 
                 ASSERT(state & psflg_running_sys);
@@ -10907,7 +10166,7 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
                     n &= ~psflg_running_sys;
                     n |= psflg_running;
 
-                    state = erts_smp_atomic32_cmpxchg_mb(&p->state, n, e);
+                    state = erts_atomic32_cmpxchg_mb(&p->state, n, e);
                     if (state == e) {
                         state = n;
                         break;
@@ -10926,10 +10185,8 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
                     reds -= cost;
                     if (reds <= 0)
                         goto sched_out_proc;
-#ifdef ERTS_DIRTY_SCHEDULERS
                     if (p->flags & (F_DIRTY_MAJOR_GC|F_DIRTY_MINOR_GC))
                         goto sched_out_proc;
-#endif
                 }
             }
         }
@@ -10941,12 +10198,12 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 
 	p->fcalls = reds;
 	    
-	ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
+	ERTS_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
 
 	/* Never run a suspended process */
 #ifdef DEBUG
         {
-            erts_aint32_t dstate = erts_smp_atomic32_read_nob(&p->state);
+            erts_aint32_t dstate = erts_atomic32_read_nob(&p->state);
             ASSERT(!(ERTS_PSFLG_SUSPENDED & dstate)
                    || (ERTS_PSFLG_DIRTY_RUNNING_SYS & dstate));
         }
@@ -10956,9 +10213,7 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls)
 
 	if (!(state & ERTS_PSFLG_EXITING) && ERTS_PTMR_IS_TIMED_OUT(p)) {
 	    BeamInstr** pi;
-#ifdef ERTS_SMP
 	    ETHR_MEMBAR(ETHR_LoadLoad|ETHR_LoadStore);
-#endif
 	    pi = (BeamInstr **) p->def_arg_reg;
 	    p->i = *pi;
 	    p->flags &= ~F_INSLPQUEUE;
@@ -10975,13 +10230,11 @@ notify_sys_task_executed(Process *c_p, ErtsProcSysTask *st,
 			 Eterm st_result, int normal_sched)
 {
     Process *rp;
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (!normal_sched)
 	rp = erts_pid2proc_opt(c_p, ERTS_PROC_LOCK_MAIN,
 			       st->requester, 0,
 			       ERTS_P2P_FLG_INC_REFC);
     else
-#endif
 	rp = erts_proc_lookup(st->requester);
     if (rp) {
 	ErtsProcLocks rp_locks;
@@ -11029,12 +10282,10 @@ notify_sys_task_executed(Process *c_p, ErtsProcSysTask *st,
 	    rp_locks &= ~ERTS_PROC_LOCK_MAIN;
 
 	if (rp_locks)
-	    erts_smp_proc_unlock(rp, rp_locks);
+	    erts_proc_unlock(rp, rp_locks);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 	if (!normal_sched)
 	    erts_proc_dec_refc(rp);
-#endif
     }
 
     erts_cleanup_offheap(&st->off_heap);
@@ -11053,7 +10304,7 @@ fetch_sys_task(Process *c_p, erts_aint32_t state, int *qmaskp, int *priop)
 
     *priop = -1; /* Shut up annoying erroneous warning */
 
-    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_lock(c_p, ERTS_PROC_LOCK_STATUS);
 
     if (!c_p->sys_task_qs) {
 	qmask = 0;
@@ -11173,13 +10424,13 @@ fetch_sys_task(Process *c_p, erts_aint32_t state, int *qmaskp, int *priop)
 
 	    if (a == n)
 		break;
-	    a = erts_smp_atomic32_cmpxchg_nob(&c_p->state, n, e);
+	    a = erts_atomic32_cmpxchg_nob(&c_p->state, n, e);
 	} while (a != e);
     }
 
 done:
 
-    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_unlock(c_p, ERTS_PROC_LOCK_STATUS);
 
     if (unused_qs)
 	proc_sys_task_queues_free(unused_qs);
@@ -11190,9 +10441,7 @@ done:
 }
 
 static void save_gc_task(Process *c_p, ErtsProcSysTask *st, int prio);
-#ifdef ERTS_DIRTY_SCHEDULERS
 static void save_dirty_task(Process *c_p, ErtsProcSysTask *st);
-#endif
 
 static int
 execute_sys_tasks(Process *c_p, erts_aint32_t *statep, int in_reds)
@@ -11203,7 +10452,7 @@ execute_sys_tasks(Process *c_p, erts_aint32_t *statep, int in_reds)
     int qmask = 0;
 
     ASSERT(!ERTS_SCHEDULER_IS_DIRTY(erts_proc_sched_data(c_p)));
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == ERTS_PROC_LOCK_MAIN);
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == ERTS_PROC_LOCK_MAIN);
 
     do {
 	ErtsProcSysTaskType type;
@@ -11212,10 +10461,8 @@ execute_sys_tasks(Process *c_p, erts_aint32_t *statep, int in_reds)
 	Eterm st_res;
 
 	if (state & (ERTS_PSFLG_EXITING|ERTS_PSFLG_PENDING_EXIT)) {
-#ifdef ERTS_SMP
 	    if (state & ERTS_PSFLG_PENDING_EXIT)
 		erts_handle_pending_exit(c_p, ERTS_PROC_LOCK_MAIN);
-#endif
 	    ASSERT(ERTS_PROC_IS_EXITING(c_p));
 	    break;
 	}
@@ -11242,13 +10489,11 @@ execute_sys_tasks(Process *c_p, erts_aint32_t *statep, int in_reds)
                         FLAGS(c_p) |= F_NEED_FULLSWEEP;
                     }
 		    reds -= scheduler_gc_proc(c_p, reds);
-#ifdef ERTS_DIRTY_SCHEDULERS
 		    if (c_p->flags & (F_DIRTY_MAJOR_GC|F_DIRTY_MINOR_GC)) {
 			save_dirty_task(c_p, st);
 			st = NULL;
 			break;
 		    }
-#endif
 		    if (type == ERTS_PSTT_GC_MAJOR)
 			minor_gc = major_gc = 1;
 		    else
@@ -11290,13 +10535,11 @@ execute_sys_tasks(Process *c_p, erts_aint32_t *statep, int in_reds)
 						 fcalls, do_gc);
             reds -= cla_reds;
 	    if (is_non_value(st_res)) {
-#ifdef ERTS_DIRTY_SCHEDULERS
 		if (c_p->flags & F_DIRTY_CLA) {
 		    save_dirty_task(c_p, st);
 		    st = NULL;
 		    break;
 		}
-#endif
 		/* Needed gc, but gc was disabled */
 		save_gc_task(c_p, st, st_prio);
 		st = NULL;
@@ -11310,18 +10553,14 @@ execute_sys_tasks(Process *c_p, erts_aint32_t *statep, int in_reds)
 	    reds -= erts_complete_off_heap_message_queue_change(c_p);
 	    st_res = am_true;
 	    break;
-#ifdef ERTS_SMP
         case ERTS_PSTT_FTMQ:
 	    reds -= erts_flush_trace_messages(c_p, ERTS_PROC_LOCK_MAIN);
 	    st_res = am_true;
 	    break;
-#endif
-#ifdef ERTS_SMP
         case ERTS_PSTT_ETS_FREE_FIXATION:
 	    reds -= erts_db_execute_free_fixation(c_p, (DbFixation*)st->arg[0]);
 	    st_res = am_true;
 	    break;
-#endif
 	default:
 	    ERTS_INTERNAL_ERROR("Invalid process sys task type");
 	    st_res = am_false;
@@ -11330,7 +10569,7 @@ execute_sys_tasks(Process *c_p, erts_aint32_t *statep, int in_reds)
 	if (st)
 	    reds += notify_sys_task_executed(c_p, st, st_res, 1);
 
-	state = erts_smp_atomic32_read_acqb(&c_p->state);
+	state = erts_atomic32_read_acqb(&c_p->state);
     } while (qmask && reds > 0);
 
     *statep = state;
@@ -11351,20 +10590,18 @@ cleanup_sys_tasks(Process *c_p, erts_aint32_t in_state, int in_reds)
                              * are dirty tasks.
                              */
 
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == ERTS_PROC_LOCK_MAIN);
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == ERTS_PROC_LOCK_MAIN);
 
     do {
 	ErtsProcSysTask *st;
 	Eterm st_res;
 	int st_prio;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 	if (c_p->dirty_sys_tasks) {
 	    st = c_p->dirty_sys_tasks;
 	    c_p->dirty_sys_tasks = st->next;
 	}
 	else
-#endif
 	{
 	    st = fetch_sys_task(c_p, state, &qmask, &st_prio);
 	    if (!st)
@@ -11382,12 +10619,10 @@ cleanup_sys_tasks(Process *c_p, erts_aint32_t in_state, int in_reds)
 	case ERTS_PSTT_CLA:
 	    st_res = am_ok;
 	    break;
-#ifdef ERTS_SMP
         case ERTS_PSTT_FTMQ:
 	    reds -= erts_flush_trace_messages(c_p, ERTS_PROC_LOCK_MAIN);
 	    st_res = am_true;
 	    break;
-#endif
 	default:
 	    ERTS_INTERNAL_ERROR("Invalid process sys task type");
 	    st_res = am_false;
@@ -11396,13 +10631,12 @@ cleanup_sys_tasks(Process *c_p, erts_aint32_t in_state, int in_reds)
 
 	reds += notify_sys_task_executed(c_p, st, st_res, 1);
 
-	state = erts_smp_atomic32_read_acqb(&c_p->state);
+	state = erts_atomic32_read_acqb(&c_p->state);
     } while (qmask && reds < max_reds);
 
     return reds;
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 void
 erts_execute_dirty_system_task(Process *c_p)
@@ -11431,19 +10665,19 @@ erts_execute_dirty_system_task(Process *c_p)
     }
 
     if (c_p->flags & F_DIRTY_GC_HIBERNATE) {
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
-	ERTS_SMP_MSGQ_MV_INQ2PRIVQ(c_p);
+	erts_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
+	ERTS_MSGQ_MV_INQ2PRIVQ(c_p);
 	if (c_p->msg.len)
             c_p->flags &= ~F_DIRTY_GC_HIBERNATE; /* operation aborted... */
         else {
-	    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
+	    erts_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
 	    c_p->fvalue = NIL;
 	    erts_garbage_collect_hibernate(c_p);
 	    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
+	    erts_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
 	    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
 	}
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
     }
 
     if (c_p->flags & (F_DIRTY_MAJOR_GC|F_DIRTY_MINOR_GC)) {
@@ -11487,7 +10721,7 @@ erts_execute_dirty_system_task(Process *c_p)
 
     }
 
-    erts_smp_atomic32_read_band_relb(&c_p->state, ~ERTS_PSFLG_DIRTY_ACTIVE_SYS);
+    erts_atomic32_read_band_relb(&c_p->state, ~ERTS_PSFLG_DIRTY_ACTIVE_SYS);
 }
 
 static BIF_RETTYPE
@@ -11540,12 +10774,11 @@ dispatch_system_task(Process *c_p, erts_aint_t fail_state,
     erts_queue_message(rp, rp_locks, mp, msg, st->requester);
 
     if (rp_locks)
-	erts_smp_proc_unlock(rp, rp_locks);
+	erts_proc_unlock(rp, rp_locks);
 
     return ret;
 }
 
-#endif
 
 static BIF_RETTYPE
 request_system_task(Process *c_p, Eterm requester, Eterm target,
@@ -11650,7 +10883,6 @@ request_system_task(Process *c_p, Eterm requester, Eterm target,
 	st->type = ERTS_PSTT_CPC;
 	if (!rp)
 	    goto noproc;
-#ifdef ERTS_DIRTY_SCHEDULERS
 	/*
 	 * If the process should start executing dirty
 	 * code it is important that this task is
@@ -11658,7 +10890,6 @@ request_system_task(Process *c_p, Eterm requester, Eterm target,
 	 */
 	fail_state |= (ERTS_PSFLG_DIRTY_RUNNING
 		       | ERTS_PSFLG_DIRTY_RUNNING_SYS);
-#endif
 	break;
 
     case am_copy_literals:
@@ -11680,14 +10911,12 @@ request_system_task(Process *c_p, Eterm requester, Eterm target,
 	noproc:
 	    failure = noproc_res;
 	}
-#ifdef ERTS_DIRTY_SCHEDULERS
 	else if (fail_state & (ERTS_PSFLG_DIRTY_RUNNING
 			       | ERTS_PSFLG_DIRTY_RUNNING_SYS)) {
 	    ret = dispatch_system_task(c_p, fail_state, st,
 				       target, priority, operation);
 	    goto cleanup_return;
 	}
-#endif
 	else {
 	    ERTS_INTERNAL_ERROR("Unknown failure schedule_process_sys_task()");
 	    failure = am_internal_error;
@@ -11703,9 +10932,7 @@ badarg:
 
     ERTS_BIF_PREP_ERROR(ret, c_p, BADARG);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 cleanup_return:
-#endif
 
     if (st) {
 	erts_cleanup_offheap(&st->off_heap);
@@ -11746,7 +10973,7 @@ erts_schedule_generic_sys_task(Eterm pid, ErtsProcSysTaskType type, void* arg)
 	st->req_id_sz = 0;
         st->arg[0] = (Eterm)arg;
 	ERTS_INIT_OFF_HEAP(&st->off_heap);
-	state = erts_smp_atomic32_read_nob(&rp->state);
+	state = erts_atomic32_read_nob(&rp->state);
 
 	fail_state = ERTS_PSFLG_EXITING;
 
@@ -11769,7 +10996,6 @@ erts_schedule_ets_free_fixation(Eterm pid, DbFixation* fix)
     erts_schedule_generic_sys_task(pid, ERTS_PSTT_ETS_FREE_FIXATION, fix);
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 static void
 flush_dirty_trace_messages(void *vpid)
@@ -11786,45 +11012,35 @@ flush_dirty_trace_messages(void *vpid)
     proc = erts_pid2proc_opt(NULL, 0, pid, ERTS_PROC_LOCK_MAIN, 0);
     if (proc) {
 	(void) erts_flush_trace_messages(proc, ERTS_PROC_LOCK_MAIN);
-        erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
+        erts_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
     }
 }
 
-#endif /* ERTS_DIRTY_SCHEDULERS */
 
 void
 erts_schedule_flush_trace_messages(Process *proc, int force_on_proc)
 {
-#ifdef ERTS_SMP
     ErtsThrPrgrDelayHandle dhndl;
-#endif
     Eterm pid = proc->common.id;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     erts_aint32_t state;
 
     if (!force_on_proc) {
-	state = erts_smp_atomic32_read_nob(&proc->state);
+	state = erts_atomic32_read_nob(&proc->state);
 	if (state & (ERTS_PSFLG_DIRTY_RUNNING
 		     | ERTS_PSFLG_DIRTY_RUNNING_SYS)) {
 	    goto sched_flush_dirty;
 	}
     }
-#endif
 
-#ifdef ERTS_SMP
     dhndl = erts_thr_progress_unmanaged_delay();
-#endif
 
     erts_schedule_generic_sys_task(pid, ERTS_PSTT_FTMQ, NULL);
 
-#ifdef ERTS_SMP
     erts_thr_progress_unmanaged_continue(dhndl);
-#endif
 
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (!force_on_proc) {
-	state = erts_smp_atomic32_read_mb(&proc->state);
+	state = erts_atomic32_read_mb(&proc->state);
 	if (state & (ERTS_PSFLG_DIRTY_RUNNING
 		     | ERTS_PSFLG_DIRTY_RUNNING_SYS)) {
 	    void *vargp;
@@ -11852,7 +11068,6 @@ erts_schedule_flush_trace_messages(Process *proc, int force_on_proc)
 	    erts_schedule_misc_aux_work(1, flush_dirty_trace_messages, vargp);
 	}
     }
-#endif
 }
 
 static void
@@ -11861,7 +11076,7 @@ save_gc_task(Process *c_p, ErtsProcSysTask *st, int prio)
     erts_aint32_t state;
     ErtsProcSysTaskQs *qs;
 
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(c_p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(c_p));
 
     qs = ERTS_PROC_GET_DELAYED_GC_TASK_QS(c_p);
     if (!qs) {
@@ -11891,7 +11106,7 @@ save_gc_task(Process *c_p, ErtsProcSysTask *st, int prio)
 	}
     }
 
-    state = erts_smp_atomic32_read_nob(&c_p->state);
+    state = erts_atomic32_read_nob(&c_p->state);
     ASSERT((ERTS_PSFLG_RUNNING
 	    | ERTS_PSFLG_RUNNING_SYS
 	    | ERTS_PSFLG_DIRTY_RUNNING
@@ -11907,20 +11122,18 @@ save_gc_task(Process *c_p, ErtsProcSysTask *st, int prio)
 	    n &= ~ERTS_PSFLGS_ACT_PRIO_MASK;
 	    n |= prio << ERTS_PSFLGS_ACT_PRIO_OFFSET;
 	}
-	state = erts_smp_atomic32_cmpxchg_relb(&c_p->state, n, e);
+	state = erts_atomic32_cmpxchg_relb(&c_p->state, n, e);
 	if (state == e)
 	    break;
     }
 }
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 static void
 save_dirty_task(Process *c_p, ErtsProcSysTask *st)
 {
     st->next = c_p->dirty_sys_tasks;
     c_p->dirty_sys_tasks = st;
 }
-#endif
 
 int
 erts_set_gc_state(Process *c_p, int enable)
@@ -11928,8 +11141,8 @@ erts_set_gc_state(Process *c_p, int enable)
     ErtsProcSysTaskQs *dgc_tsk_qs;
     ASSERT(c_p == erts_get_current_process());
     ASSERT((ERTS_PSFLG_RUNNING|ERTS_PSFLG_RUNNING_SYS)
-	   & erts_smp_atomic32_read_nob(&c_p->state));
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(c_p));
+	   & erts_atomic32_read_nob(&c_p->state));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(c_p));
 
     if (!enable) {
 	c_p->flags |= F_DISABLE_GC;
@@ -11944,7 +11157,7 @@ erts_set_gc_state(Process *c_p, int enable)
 
     /* Move delayed gc tasks into sys tasks queues. */
 
-    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_lock(c_p, ERTS_PROC_LOCK_STATUS);
 
     if (!c_p->sys_task_qs) {
 	c_p->sys_task_qs = dgc_tsk_qs;
@@ -12017,7 +11230,7 @@ erts_set_gc_state(Process *c_p, int enable)
 	erts_aint32_t aprio, state =
 #endif
 
-	    erts_smp_atomic32_read_bset_nob(&c_p->state,
+	    erts_atomic32_read_bset_nob(&c_p->state,
 					    (ERTS_PSFLG_DELAYED_SYS
 					     | ERTS_PSFLG_ACTIVE_SYS),
 					    ERTS_PSFLG_ACTIVE_SYS);
@@ -12031,7 +11244,7 @@ erts_set_gc_state(Process *c_p, int enable)
     }
 #endif
 
-    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_unlock(c_p, ERTS_PROC_LOCK_STATUS);
 
     (void) ERTS_PROC_SET_DELAYED_GC_TASK_QS(c_p, NULL);
 
@@ -12047,24 +11260,24 @@ erts_sched_stat_modify(int what)
     int ix;
     switch (what) {
     case ERTS_SCHED_STAT_MODIFY_ENABLE:
-	erts_smp_thr_progress_block();
+	erts_thr_progress_block();
 	erts_sched_stat.enabled = 1;
-	erts_smp_thr_progress_unblock();
+	erts_thr_progress_unblock();
 	break;
     case ERTS_SCHED_STAT_MODIFY_DISABLE:
-	erts_smp_thr_progress_block();
+	erts_thr_progress_block();
 	erts_sched_stat.enabled = 0;
-	erts_smp_thr_progress_unblock();
+	erts_thr_progress_unblock();
 	break;
     case ERTS_SCHED_STAT_MODIFY_CLEAR:
-	erts_smp_spin_lock(&erts_sched_stat.lock);
+	erts_spin_lock(&erts_sched_stat.lock);
 	for (ix = 0; ix < ERTS_NO_PRIO_LEVELS; ix++) {
 	    erts_sched_stat.prio[ix].total_executed = 0;
 	    erts_sched_stat.prio[ix].executed = 0;
 	    erts_sched_stat.prio[ix].total_migrated = 0;
 	    erts_sched_stat.prio[ix].migrated = 0;
 	}
-	erts_smp_spin_unlock(&erts_sched_stat.lock);
+	erts_spin_unlock(&erts_sched_stat.lock);
 	break;
     }
 }
@@ -12078,7 +11291,7 @@ erts_sched_stat_term(Process *p, int total)
     Uint executed[ERTS_NO_PRIO_LEVELS];
     Uint migrated[ERTS_NO_PRIO_LEVELS];
 
-    erts_smp_spin_lock(&erts_sched_stat.lock);
+    erts_spin_lock(&erts_sched_stat.lock);
     if (total) {
 	int i;
 	for (i = 0; i < ERTS_NO_PRIO_LEVELS; i++) {
@@ -12097,7 +11310,7 @@ erts_sched_stat_term(Process *p, int total)
 	    erts_sched_stat.prio[i].migrated = 0;
 	}
     }
-    erts_smp_spin_unlock(&erts_sched_stat.lock);
+    erts_spin_unlock(&erts_sched_stat.lock);
 
     sz = 0;
     (void) erts_bld_atom_2uint_3tup_list(NULL, &sz, ERTS_NO_PRIO_LEVELS,
@@ -12117,7 +11330,6 @@ erts_schedule_misc_op(void (*func)(void *), void *arg)
     ErtsSchedulerData *esdp = erts_get_scheduler_data();
     ErtsRunQueue *rq = esdp ? esdp->run_queue : ERTS_RUNQ_IX(0);
     ErtsMiscOpList *molp = misc_op_list_alloc();
-#ifdef ERTS_SMP
     ErtsMigrationPaths *mpaths = erts_get_migration_paths();
 
     if (!mpaths)
@@ -12127,9 +11339,8 @@ erts_schedule_misc_op(void (*func)(void *), void *arg)
 	if (erq)
 	    rq = erq;
     }
-#endif
 
-    erts_smp_runq_lock(rq);
+    erts_runq_lock(rq);
 
     molp->next = NULL;
     molp->func = func;
@@ -12140,13 +11351,11 @@ erts_schedule_misc_op(void (*func)(void *), void *arg)
 	rq->misc.start = molp;
     rq->misc.end = molp;
 
-#ifdef ERTS_SMP
     non_empty_runq(rq);
-#endif
 
     ERTS_RUNQ_FLGS_SET_NOB(rq, ERTS_RUNQ_FLG_MISC_OP);
 
-    erts_smp_runq_unlock(rq);
+    erts_runq_unlock(rq);
 
     smp_notify_inc_runq(rq);
 }
@@ -12179,7 +11388,7 @@ exec_misc_ops(ErtsRunQueue *rq)
     if (!rq->misc.start)
         ERTS_RUNQ_FLGS_UNSET_NOB(rq, ERTS_RUNQ_FLG_MISC_OP);
 
-    erts_smp_runq_unlock(rq);
+    erts_runq_unlock(rq);
 
     while (molp) {
 	tmp_molp = molp;
@@ -12188,7 +11397,7 @@ exec_misc_ops(ErtsRunQueue *rq)
 	misc_op_list_free(tmp_molp);
     }
 
-    erts_smp_runq_lock(rq);
+    erts_runq_lock(rq);
 }
 
 Uint
@@ -12219,12 +11428,12 @@ erts_get_exact_total_reductions(Process *c_p, Uint *redsp, Uint *diffp)
 {
     Uint reds = erts_current_reductions(c_p, c_p);
     int ix;
-    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+    erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
     /*
      * Wait for other schedulers to schedule out their processes
      * and update 'reductions'.
      */
-    erts_smp_thr_progress_block();
+    erts_thr_progress_block();
     for (reds = 0, ix = 0; ix < erts_no_run_queues; ix++)
 	reds += ERTS_RUNQ_IX(ix)->procs.reductions;
     if (redsp)
@@ -12232,8 +11441,8 @@ erts_get_exact_total_reductions(Process *c_p, Uint *redsp, Uint *diffp)
     if (diffp)
 	*diffp = reds - last_exact_reductions;
     last_exact_reductions = reds;
-    erts_smp_thr_progress_unblock();
-    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+    erts_thr_progress_unblock();
+    erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
 }
 
 static void delete_process(Process* p);
@@ -12241,10 +11450,8 @@ static void delete_process(Process* p);
 void
 erts_free_proc(Process *p)
 {
-#ifdef ERTS_SMP
     erts_proc_lock_fin(p);
-#endif
-    ASSERT(erts_smp_atomic32_read_nob(&p->state) & ERTS_PSFLG_FREE);
+    ASSERT(erts_atomic32_read_nob(&p->state) & ERTS_PSFLG_FREE);
     ASSERT(0 == erts_proc_read_refc(p));
     if (p->flags & F_DELAYED_DEL_PROC)
 	delete_process(p);
@@ -12263,17 +11470,13 @@ static void early_init_process_struct(void *varg, Eterm data)
     Process *proc = arg->proc;
 
     proc->common.id = make_internal_pid(data);
-#ifdef ERTS_DIRTY_SCHEDULERS
-    erts_smp_atomic32_init_nob(&proc->dirty_state, 0);
+    erts_atomic32_init_nob(&proc->dirty_state, 0);
     proc->dirty_sys_tasks = NULL;
-#endif
-    erts_smp_atomic32_init_relb(&proc->state, arg->state);
+    erts_atomic32_init_relb(&proc->state, arg->state);
 
-#ifdef ERTS_SMP
     RUNQ_SET_RQ(&proc->run_queue, arg->run_queue);
 
     erts_proc_lock_init(proc); /* All locks locked */
-#endif
 
 }
 
@@ -12346,7 +11549,7 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
     INITIALIZE_LITERAL_PURGE_AREA(litarea);
 #endif
 
-    erts_smp_proc_lock(parent, ERTS_PROC_LOCKS_ALL_MINOR);
+    erts_proc_lock(parent, ERTS_PROC_LOCKS_ALL_MINOR);
 
     /*
      * Check for errors.
@@ -12394,9 +11597,9 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
 	goto error;
     }
 
-    ASSERT((erts_smp_atomic32_read_nob(&p->state)
+    ASSERT((erts_atomic32_read_nob(&p->state)
 	    & ERTS_PSFLG_ON_HEAP_MSGQ)
-	   || (erts_smp_atomic32_read_nob(&p->state)
+	   || (erts_atomic32_read_nob(&p->state)
 	       & ERTS_PSFLG_OFF_HEAP_MSGQ));
 
 #ifdef SHCOPY_SPAWN
@@ -12422,7 +11625,7 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
 	p->min_vheap_size = BIN_VH_MIN_SIZE;
         MAX_HEAP_SIZE_SET(p, H_MAX_SIZE);
         MAX_HEAP_SIZE_FLAGS_SET(p, H_MAX_FLAGS);
-	p->max_gen_gcs    = (Uint16) erts_smp_atomic32_read_nob(&erts_max_gen_gcs);
+	p->max_gen_gcs    = (Uint16) erts_atomic32_read_nob(&erts_max_gen_gcs);
     }
     p->schedule_count = 0;
     ASSERT(p->min_heap_size == erts_next_heap_size(p->min_heap_size, 0));
@@ -12448,10 +11651,8 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
 
 #ifdef HIPE
     hipe_init_process(&p->hipe);
-#ifdef ERTS_SMP
     hipe_init_process_smp(&p->hipe_smp);
 #endif
-#endif
     p->heap = (Eterm *) ERTS_HEAP_ALLOC(ERTS_ALC_T_HEAP, sizeof(Eterm)*sz);
     p->old_hend = p->old_htop = p->old_heap = NULL;
     p->high_water = p->heap;
@@ -12520,16 +11721,14 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
     p->msg.save = &p->msg.first;
     p->msg.saved_last = &p->msg.first;
     p->msg.len = 0;
-#ifdef ERTS_SMP
     p->msg_inq.first = NULL;
     p->msg_inq.last = &p->msg_inq.first;
     p->msg_inq.len = 0;
-#endif
     p->bif_timers = NULL;
     p->mbuf = NULL;
     p->msg_frag = NULL;
     p->mbuf_sz = 0;
-    erts_smp_atomic_init_nob(&p->psd, (erts_aint_t) NULL);
+    erts_atomic_init_nob(&p->psd, (erts_aint_t) NULL);
     p->dictionary = NULL;
     p->seq_trace_lastcnt = 0;
     p->seq_trace_clock = 0;
@@ -12547,14 +11746,12 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
     p->last_old_htop = NULL;
 #endif
 
-#ifdef ERTS_SMP
     p->trace_msg_q = NULL;
     p->scheduler_data = NULL;
     p->suspendee = NIL;
     p->pending_suspenders = NULL;
     p->pending_exit.reason = THE_NON_VALUE;
     p->pending_exit.bp = NULL;
-#endif
 
 #if !defined(NO_FPE_SIGNALS) || defined(HIPE)
     p->fp_exception = 0;
@@ -12582,8 +11779,8 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
         }
         if (ARE_TRACE_FLAGS_ON(parent, F_TRACE_PROCS)) {
             locks &= ~(ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
-            erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
-            erts_smp_proc_unlock(parent, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
+            erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
+            erts_proc_unlock(parent, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
             trace_proc_spawn(parent, am_spawn, p->common.id, mod, func, args);
             if (so->flags & SPO_LINK)
                 trace_proc(parent, locks, parent, am_link, p->common.id);
@@ -12595,8 +11792,8 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
               == (ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE)) {
             /* This happens when parent was not traced, but child is */
             locks &= ~(ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
-            erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
-            erts_smp_proc_unlock(parent, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
+            erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
+            erts_proc_unlock(parent, ERTS_PROC_LOCK_STATUS|ERTS_PROC_LOCK_TRACE);
         }
         trace_proc_spawn(p, am_spawned, parent->common.id, mod, func, args);
         if (so->flags & SPO_LINK)
@@ -12635,7 +11832,7 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
 	so->mref = mref;
     }
 
-    erts_smp_proc_unlock(p, locks);
+    erts_proc_unlock(p, locks);
 
     res = p->common.id;
 
@@ -12643,7 +11840,7 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
      * Schedule process for execution.
      */
 
-    erts_smp_proc_unlock(parent, locks & ERTS_PROC_LOCKS_ALL_MINOR);
+    erts_proc_unlock(parent, locks & ERTS_PROC_LOCKS_ALL_MINOR);
 
     schedule_process(p, state, 0);
 
@@ -12663,7 +11860,7 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
 
  error:
 
-    erts_smp_proc_unlock(parent, locks & ERTS_PROC_LOCKS_ALL_MINOR);
+    erts_proc_unlock(parent, locks & ERTS_PROC_LOCKS_ALL_MINOR);
 
     return res;
 }
@@ -12714,7 +11911,7 @@ void erts_init_empty_process(Process *p)
     p->mbuf = NULL;
     p->msg_frag = NULL;
     p->mbuf_sz = 0;
-    erts_smp_atomic_init_nob(&p->psd, (erts_aint_t) NULL);
+    erts_atomic_init_nob(&p->psd, (erts_aint_t) NULL);
     ERTS_P_MONITORS(p) = NULL;
     ERTS_P_LINKS(p) = NULL;         /* List of links */
     p->nodes_monitors = NULL;
@@ -12757,23 +11954,18 @@ void erts_init_empty_process(Process *p)
 
 #ifdef HIPE
     hipe_init_process(&p->hipe);
-#ifdef ERTS_SMP
     hipe_init_process_smp(&p->hipe_smp);
 #endif
-#endif
 
     INIT_HOLE_CHECK(p);
 #ifdef DEBUG
     p->last_old_htop = NULL;
 #endif
 
-#ifdef ERTS_DIRTY_SCHEDULERS
-    erts_smp_atomic32_init_nob(&p->dirty_state, 0);
+    erts_atomic32_init_nob(&p->dirty_state, 0);
     p->dirty_sys_tasks = NULL;
-#endif
-    erts_smp_atomic32_init_nob(&p->state, (erts_aint32_t) PRIORITY_NORMAL);
+    erts_atomic32_init_nob(&p->state, (erts_aint32_t) PRIORITY_NORMAL);
 
-#ifdef ERTS_SMP
     p->scheduler_data = NULL;
     p->msg_inq.first = NULL;
     p->msg_inq.last = &p->msg_inq.first;
@@ -12783,9 +11975,8 @@ void erts_init_empty_process(Process *p)
     p->pending_exit.reason = THE_NON_VALUE;
     p->pending_exit.bp = NULL;
     erts_proc_lock_init(p);
-    erts_smp_proc_unlock(p, ERTS_PROC_LOCKS_ALL);
+    erts_proc_unlock(p, ERTS_PROC_LOCKS_ALL);
     RUNQ_SET_RQ(&p->run_queue, ERTS_RUNQ_IX(0));
-#endif
 
 #if !defined(NO_FPE_SIGNALS) || defined(HIPE)
     p->fp_exception = 0;
@@ -12832,14 +12023,12 @@ erts_debug_verify_clean_empty_process(Process* p)
 
     ASSERT(p->parent == NIL);
 
-#ifdef ERTS_SMP
     ASSERT(p->msg_inq.first == NULL);
     ASSERT(p->msg_inq.len == 0);
     ASSERT(p->suspendee == NIL);
     ASSERT(p->pending_suspenders == NULL);
     ASSERT(p->pending_exit.reason == THE_NON_VALUE);
     ASSERT(p->pending_exit.bp == NULL);
-#endif
 
     /* Thing that erts_cleanup_empty_process() cleans up */
 
@@ -12864,9 +12053,7 @@ erts_cleanup_empty_process(Process* p)
 	free_message_buffer(p->mbuf);
 	p->mbuf = NULL;
     }
-#ifdef ERTS_SMP
     erts_proc_lock_fin(p);
-#endif
 #ifdef DEBUG
     erts_debug_verify_clean_empty_process(p);
 #endif
@@ -12898,10 +12085,10 @@ delete_process(Process* p)
 
     /* Cleanup psd */
 
-    psd = (ErtsPSD *) erts_smp_atomic_read_nob(&p->psd);
+    psd = (ErtsPSD *) erts_atomic_read_nob(&p->psd);
 
     if (psd) {
-	erts_smp_atomic_set_nob(&p->psd, (erts_aint_t) NULL); /* Reduction counting depends on this... */
+	erts_atomic_set_nob(&p->psd, (erts_aint_t) NULL); /* Reduction counting depends on this... */
 	erts_free(ERTS_ALC_T_PSD, psd);
     }
 
@@ -12959,7 +12146,7 @@ set_proc_exiting(Process *p,
 {
     erts_aint32_t state = in_state, enq_prio = -1;
     int enqueue;
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(p) == ERTS_PROC_LOCKS_ALL);
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(p) == ERTS_PROC_LOCKS_ALL);
 
     enqueue = change_proc_schedule_state(p,
 					 (ERTS_PSFLG_SUSPENDED
@@ -12982,22 +12169,6 @@ set_proc_exiting(Process *p,
     KILL_CATCHES(p);
     p->i = (BeamInstr *) beam_exit;
 
-#ifndef ERTS_SMP
-    if (state & (ERTS_PSFLG_RUNNING|ERTS_PSFLG_RUNNING_SYS)
-        && !(state & ERTS_PSFLG_GC)) {
-	/*
-	 * I non smp case:
-	 *
-	 * Currently executing process might be sent an exit
-	 * signal if it is traced by a port that it also is
-	 * linked to, and the port terminates during the
-	 * trace. In this case we want schedule out the
-	 * process as quickly as possible in order to detect
-	 * the event as fast as possible.
-	 */
-	ERTS_VBUMP_ALL_REDS(p);
-    }
-#endif
 
     add2runq(enqueue, enq_prio, p, state, NULL);
 }
@@ -13010,9 +12181,9 @@ set_proc_self_exiting(Process *c_p)
 #endif
     erts_aint32_t state, enq_prio = -1;
 
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == ERTS_PROC_LOCKS_ALL);
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == ERTS_PROC_LOCKS_ALL);
 
-    state = erts_smp_atomic32_read_nob(&c_p->state);
+    state = erts_atomic32_read_nob(&c_p->state);
     ASSERT(state & (ERTS_PSFLG_RUNNING
 		    |ERTS_PSFLG_RUNNING_SYS
 		    | ERTS_PSFLG_DIRTY_RUNNING
@@ -13032,38 +12203,37 @@ set_proc_self_exiting(Process *c_p)
     return state;
 }
 
-#ifdef ERTS_SMP
 
 void
 erts_handle_pending_exit(Process *c_p, ErtsProcLocks locks)
 {
     ErtsProcLocks xlocks;
     ASSERT(is_value(c_p->pending_exit.reason));
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == locks);
-    ERTS_SMP_LC_ASSERT(locks & ERTS_PROC_LOCK_MAIN);
-    ERTS_SMP_LC_ASSERT(!((ERTS_PSFLG_EXITING|ERTS_PSFLG_FREE)
-			 & erts_smp_atomic32_read_nob(&c_p->state)));
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == locks);
+    ERTS_LC_ASSERT(locks & ERTS_PROC_LOCK_MAIN);
+    ERTS_LC_ASSERT(!((ERTS_PSFLG_EXITING|ERTS_PSFLG_FREE)
+			 & erts_atomic32_read_nob(&c_p->state)));
 
     /* Ensure that all locks on c_p are locked before proceeding... */
     if (locks == ERTS_PROC_LOCKS_ALL)
 	xlocks = 0;
     else {
 	xlocks = ~locks & ERTS_PROC_LOCKS_ALL;
-	if (erts_smp_proc_trylock(c_p, xlocks) == EBUSY) {
-	    erts_smp_proc_unlock(c_p, locks & ~ERTS_PROC_LOCK_MAIN);
-	    erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+	if (erts_proc_trylock(c_p, xlocks) == EBUSY) {
+	    erts_proc_unlock(c_p, locks & ~ERTS_PROC_LOCK_MAIN);
+	    erts_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 	}
     }
 
     set_proc_exiting(c_p,
-		     erts_smp_atomic32_read_acqb(&c_p->state),
+		     erts_atomic32_read_acqb(&c_p->state),
 		     c_p->pending_exit.reason,
 		     c_p->pending_exit.bp);
     c_p->pending_exit.reason = THE_NON_VALUE;
     c_p->pending_exit.bp = NULL;
 
     if (xlocks)
-	erts_smp_proc_unlock(c_p, xlocks);
+	erts_proc_unlock(c_p, xlocks);
 }
 
 static void save_pending_exiter(Process *p, ErtsProcList *plp);
@@ -13084,9 +12254,9 @@ do_handle_pending_exiters(ErtsProcList *pnd_xtrs)
 	     * pending exit will soon be detected and handled by the
 	     * scheduler running the process (at schedule in/out).
 	     */
-	    if (erts_smp_proc_trylock(p, ERTS_PROC_LOCKS_ALL) != EBUSY) {
+	    if (erts_proc_trylock(p, ERTS_PROC_LOCKS_ALL) != EBUSY) {
 		if (erts_proclist_same(plp, p)) {
-		    state = erts_smp_atomic32_read_acqb(&p->state);
+		    state = erts_atomic32_read_acqb(&p->state);
 		    if (!(state & (ERTS_PSFLG_RUNNING
 				   | ERTS_PSFLG_RUNNING_SYS
 				   | ERTS_PSFLG_EXITING))) {
@@ -13094,12 +12264,12 @@ do_handle_pending_exiters(ErtsProcList *pnd_xtrs)
 			erts_handle_pending_exit(p, ERTS_PROC_LOCKS_ALL);
 		    }
 		}
-		erts_smp_proc_unlock(p, ERTS_PROC_LOCKS_ALL);
+		erts_proc_unlock(p, ERTS_PROC_LOCKS_ALL);
 	    }
 	    else {
-		erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+		erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
 		if (erts_proclist_same(plp, p)) {
-		    state = erts_smp_atomic32_read_acqb(&p->state);
+		    state = erts_atomic32_read_acqb(&p->state);
 		    if (!(state & (ERTS_PSFLG_RUNNING
 				   | ERTS_PSFLG_RUNNING_SYS
 				   | ERTS_PSFLG_EXITING))) {
@@ -13111,7 +12281,7 @@ do_handle_pending_exiters(ErtsProcList *pnd_xtrs)
 			plp = NULL;
 		    }
 		}
-		erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+		erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
 	    }
 	}
 	if (plp)
@@ -13126,7 +12296,7 @@ save_pending_exiter(Process *p, ErtsProcList *plp)
     ErtsSchedulerSleepInfo *ssi;
     ErtsRunQueue *rq;
 
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p));
 
     rq = RUNQ_READ_RQ(&p->run_queue);
     ASSERT(rq && !ERTS_RUNQ_IX_IS_DIRTY(rq->ix));
@@ -13134,7 +12304,7 @@ save_pending_exiter(Process *p, ErtsProcList *plp)
     if (!plp)
 	plp = proclist_create(p);
 
-    erts_smp_runq_lock(rq);
+    erts_runq_lock(rq);
 
     erts_proclist_store_last(&rq->procs.pending_exiters, plp);
 
@@ -13142,12 +12312,11 @@ save_pending_exiter(Process *p, ErtsProcList *plp)
 
     ssi = rq->scheduler->ssi;
 
-    erts_smp_runq_unlock(rq);
+    erts_runq_unlock(rq);
 
     set_aux_work_flags_wakeup_nob(ssi, ERTS_SSI_AUX_WORK_PENDING_EXITERS);
 }
 
-#endif
 
 /*
  * This function delivers an EXIT message to a process
@@ -13283,11 +12452,11 @@ send_exit_signal(Process *c_p,		/* current process if and only
 		 Uint32 flags		/* flags */
     )		
 {
-    erts_aint32_t state = erts_smp_atomic32_read_nob(&rp->state);
+    erts_aint32_t state = erts_atomic32_read_nob(&rp->state);
     Eterm rsn = reason == am_kill ? am_killed : reason;
 
-    ERTS_SMP_LC_ASSERT(*rp_locks == erts_proc_lc_my_proc_locks(rp));
-    ERTS_SMP_LC_ASSERT((*rp_locks & ERTS_PROC_LOCKS_XSIG_SEND)
+    ERTS_LC_ASSERT(*rp_locks == erts_proc_lc_my_proc_locks(rp));
+    ERTS_LC_ASSERT((*rp_locks & ERTS_PROC_LOCKS_XSIG_SEND)
 		       == ERTS_PROC_LOCKS_XSIG_SEND);
 
     ASSERT(reason != THE_NON_VALUE);
@@ -13308,7 +12477,7 @@ send_exit_signal(Process *c_p,		/* current process if and only
     if ((state & ERTS_PSFLG_TRAP_EXIT)
 	&& (reason != am_kill || (flags & ERTS_XSIG_FLG_IGN_KILL))) {
         /* have to release the status and trace lock in order to send the exit message */
-        erts_smp_proc_unlock(rp, *rp_locks & (ERTS_PROC_LOCKS_XSIG_SEND|ERTS_PROC_LOCK_TRACE));
+        erts_proc_unlock(rp, *rp_locks & (ERTS_PROC_LOCKS_XSIG_SEND|ERTS_PROC_LOCK_TRACE));
         *rp_locks &= ~(ERTS_PROC_LOCKS_XSIG_SEND|ERTS_PROC_LOCK_TRACE);
         if (have_seqtrace(token) && token_update)
 	    seq_trace_update_send(token_update);
@@ -13319,7 +12488,6 @@ send_exit_signal(Process *c_p,		/* current process if and only
 	return 1; /* Receiver will get a message */
     }
     else if (reason != am_normal || (flags & ERTS_XSIG_FLG_NO_IGN_NORMAL)) {
-#ifdef ERTS_SMP
 	if (!(state & (ERTS_PSFLG_EXITING|ERTS_PSFLG_PENDING_EXIT))) {
 	    ASSERT(!rp->pending_exit.bp);
 
@@ -13329,10 +12497,10 @@ send_exit_signal(Process *c_p,		/* current process if and only
 		if (*rp_locks != ERTS_PROC_LOCKS_ALL) {
 		    ErtsProcLocks need_locks = (~(*rp_locks)
 						& ERTS_PROC_LOCKS_ALL);
-		    if (erts_smp_proc_trylock(c_p, need_locks) == EBUSY) {
-			erts_smp_proc_unlock(c_p,
+		    if (erts_proc_trylock(c_p, need_locks) == EBUSY) {
+			erts_proc_unlock(c_p,
 					     *rp_locks & ~ERTS_PROC_LOCK_MAIN);
-			erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+			erts_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
 		    }
 		    *rp_locks = ERTS_PROC_LOCKS_ALL;
 		}
@@ -13346,7 +12514,7 @@ send_exit_signal(Process *c_p,		/* current process if and only
 		ErlHeapFragment *bp = NULL;
 		Eterm rsn_cpy;
 		if (need_locks
-		    && erts_smp_proc_trylock(rp, need_locks) == EBUSY) {
+		    && erts_proc_trylock(rp, need_locks) == EBUSY) {
 		    /* ... but we havn't got all locks on it ... */
 		    save_pending_exiter(rp, NULL); 
 		    /*
@@ -13358,7 +12526,7 @@ send_exit_signal(Process *c_p,		/* current process if and only
                 /* ...and we have all locks on it... */
                 *rp_locks = ERTS_PROC_LOCKS_ALL;
 
-		state = erts_smp_atomic32_read_nob(&rp->state);
+		state = erts_atomic32_read_nob(&rp->state);
 
 		if (is_immed(rsn))
 		    rsn_cpy = rsn;
@@ -13366,14 +12534,12 @@ send_exit_signal(Process *c_p,		/* current process if and only
 		    Eterm *hp;
 		    ErlOffHeap *ohp;
 		    Uint rsn_sz = size_object(rsn);
-#ifdef ERTS_DIRTY_SCHEDULERS
 		    if (state & ERTS_PSFLG_DIRTY_RUNNING) {
 			bp = new_message_buffer(rsn_sz);
 			ohp = &bp->off_heap;
 			hp = &bp->mem[0];
 		    }
 		    else
-#endif
 		    {
 			hp = HAlloc(rp, rsn_sz);
 			ohp = &rp->off_heap;
@@ -13413,12 +12579,8 @@ send_exit_signal(Process *c_p,		/* current process if and only
                  * has been scheduled, we may need to add it to a normal run
                  * queue...
 		 */
-#ifndef ERTS_DIRTY_SCHEDULERS
-                (void) erts_smp_atomic32_read_bor_relb(&rp->state,
-                                                       ERTS_PSFLG_PENDING_EXIT);
-#else
                 {
-                    erts_aint32_t a = erts_smp_atomic32_read_nob(&rp->state);
+                    erts_aint32_t a = erts_atomic32_read_nob(&rp->state);
                     while (1) {
                         erts_aint32_t n, e;
                         int dwork;
@@ -13426,7 +12588,7 @@ send_exit_signal(Process *c_p,		/* current process if and only
                         n |= ERTS_PSFLG_PENDING_EXIT;
                         dwork = !!(n & ERTS_PSFLGS_DIRTY_WORK);
                         n &= ~ERTS_PSFLGS_DIRTY_WORK;
-                        a = erts_smp_atomic32_cmpxchg_mb(&rp->state, n, e);
+                        a = erts_atomic32_cmpxchg_mb(&rp->state, n, e);
                         if (a == e) {
                             if (dwork)
                                 erts_schedule_process(rp, n, *rp_locks);
@@ -13434,7 +12596,6 @@ send_exit_signal(Process *c_p,		/* current process if and only
                         }
                     }
                 }
-#endif
 	    }
 	}
 	/* else:
@@ -13446,17 +12607,6 @@ send_exit_signal(Process *c_p,		/* current process if and only
 	 *          that the receiver *will* exit; either on the pending
 	 *          exit or by itself before seeing the pending exit.
 	 */
-#else /* !ERTS_SMP */
-	erts_aint32_t state = erts_smp_atomic32_read_nob(&rp->state);
-	if (!(state & ERTS_PSFLG_EXITING)) {
-	    set_proc_exiting(rp,
-			     state,
-			     (is_immed(rsn) || c_p == rp
-			      ? rsn
-			      : copy_object(rsn, rp)),
-			     NULL);
-	}
-#endif
 	return -1; /* Receiver will exit */
     }
 
@@ -13504,14 +12654,16 @@ static void doit_exit_monitor(ErtsMonitor *mon, void *vpcontext)
 	    ASSERT(is_node_name_atom(mon->u.pid));
 	    dep = erts_sysname_to_connected_dist_entry(mon->u.pid);
 	    if (dep) {
-		erts_smp_de_links_lock(dep);
+		erts_de_links_lock(dep);
 		rmon = erts_remove_monitor(&(dep->monitors), mon->ref);
-		erts_smp_de_links_unlock(dep);
+		erts_de_links_unlock(dep);
 		if (rmon) {
 		    ErtsDSigData dsd;
-		    int code = erts_dsig_prepare(&dsd, dep, NULL,
-						 ERTS_DSP_NO_LOCK, 0);
-		    if (code == ERTS_DSIG_PREP_CONNECTED) {
+		    int code = erts_dsig_prepare(&dsd, dep, NULL, 0,
+						 ERTS_DSP_NO_LOCK, 0, 0);
+		    if (code == ERTS_DSIG_PREP_CONNECTED ||
+                        code == ERTS_DSIG_PREP_PENDING) {
+
 			code = erts_dsig_send_demonitor(&dsd,
 							rmon->u.pid,
 							mon->name,
@@ -13521,7 +12673,6 @@ static void doit_exit_monitor(ErtsMonitor *mon, void *vpcontext)
 		    }
 		    erts_destroy_monitor(rmon);
 		}
-		erts_deref_dist_entry(dep);
 	    }
 	} else {
             ASSERT(is_pid(mon->u.pid) || is_port(mon->u.pid));
@@ -13532,7 +12683,7 @@ static void doit_exit_monitor(ErtsMonitor *mon, void *vpcontext)
 		    goto done;
 		}
 		rmon = erts_remove_monitor(&ERTS_P_MONITORS(rp), mon->ref);
-		erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+		erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 		if (rmon == NULL) {
 		    goto done;
 		}
@@ -13551,14 +12702,16 @@ static void doit_exit_monitor(ErtsMonitor *mon, void *vpcontext)
 		dep = external_pid_dist_entry(mon->u.pid);
 		ASSERT(dep != NULL);
 		if (dep) {
-		    erts_smp_de_links_lock(dep);
+		    erts_de_links_lock(dep);
 		    rmon = erts_remove_monitor(&(dep->monitors), mon->ref);
-		    erts_smp_de_links_unlock(dep);
+		    erts_de_links_unlock(dep);
 		    if (rmon) {
 			ErtsDSigData dsd;
-			int code = erts_dsig_prepare(&dsd, dep, NULL,
-						     ERTS_DSP_NO_LOCK, 0);
-			if (code == ERTS_DSIG_PREP_CONNECTED) {
+			int code = erts_dsig_prepare(&dsd, dep, NULL, 0,
+						     ERTS_DSP_NO_LOCK, 0, 0);
+			if (code == ERTS_DSIG_PREP_CONNECTED ||
+                            code == ERTS_DSIG_PREP_PENDING) {
+
 			    code = erts_dsig_send_demonitor(&dsd,
 							    rmon->u.pid,
 							    mon->u.pid,
@@ -13604,19 +12757,19 @@ static void doit_exit_monitor(ErtsMonitor *mon, void *vpcontext)
 	    }
 	    UnUseTmpHeapNoproc(3);
 	    /* else: demonitor while we exited, i.e. do nothing... */
-	    erts_smp_proc_unlock(rp, rp_locks);
+	    erts_proc_unlock(rp, rp_locks);
 	} else { /* external by pid or name */
 	    ASSERT(is_external_pid(mon->u.pid));    
 	    dep = external_pid_dist_entry(mon->u.pid);
 	    ASSERT(dep != NULL);
 	    if (dep) {
-		erts_smp_de_links_lock(dep);
+		erts_de_links_lock(dep);
 		rmon = erts_remove_monitor(&(dep->monitors), mon->ref);
-		erts_smp_de_links_unlock(dep);
+		erts_de_links_unlock(dep);
 		if (rmon) {
 		    ErtsDSigData dsd;
-		    int code = erts_dsig_prepare(&dsd, dep, NULL,
-						 ERTS_DSP_NO_LOCK, 0);
+		    int code = erts_dsig_prepare(&dsd, dep, NULL, 0,
+						 ERTS_DSP_NO_LOCK, 0, 0);
 		    if (code == ERTS_DSIG_PREP_CONNECTED) {
 			code = erts_dsig_send_m_exit(&dsd,
 						     mon->u.pid,
@@ -13720,7 +12873,7 @@ static void doit_exit_link(ErtsLink *lnk, void *vpcontext)
 			/* We didn't exit the process and it is traced */
 			if (IS_TRACED_FL(rp, F_TRACE_PROCS)) {
                             if (rp_locks & ERTS_PROC_LOCKS_XSIG_SEND) {
-                                erts_smp_proc_unlock(rp, ERTS_PROC_LOCKS_XSIG_SEND);
+                                erts_proc_unlock(rp, ERTS_PROC_LOCKS_XSIG_SEND);
                                 rp_locks &= ~ERTS_PROC_LOCKS_XSIG_SEND;
                             }
 			    trace_proc(NULL, 0, rp, am_getting_unlinked, p->common.id);
@@ -13728,7 +12881,7 @@ static void doit_exit_link(ErtsLink *lnk, void *vpcontext)
 		    }
 		}
 		ASSERT(rp != p);
-		erts_smp_proc_unlock(rp, rp_locks);
+		erts_proc_unlock(rp, rp_locks);
 	    }
 	}
 	else if (is_external_pid(item)) {
@@ -13738,14 +12891,18 @@ static void doit_exit_link(ErtsLink *lnk, void *vpcontext)
 		int code;
 		ErtsDistLinkData dld;
 		erts_remove_dist_link(&dld, p->common.id, item, dep);
-		erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
-		code = erts_dsig_prepare(&dsd, dep, p, ERTS_DSP_NO_LOCK, 0);
-		if (code == ERTS_DSIG_PREP_CONNECTED) {
-		    code = erts_dsig_send_exit_tt(&dsd, p->common.id, item,
-						  reason, SEQ_TRACE_TOKEN(p));
-		    ASSERT(code == ERTS_DSIG_SEND_OK);
-		}
-		erts_smp_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
+                if (dld.d_lnk) {
+                    erts_proc_lock(p, ERTS_PROC_LOCK_MAIN);
+                    code = erts_dsig_prepare(&dsd, dep, p, 0, ERTS_DSP_NO_LOCK, 0, 0);
+                    if (code == ERTS_DSIG_PREP_CONNECTED ||
+                        code == ERTS_DSIG_PREP_PENDING) {
+
+                        code = erts_dsig_send_exit_tt(&dsd, p->common.id, item,
+                                                      reason, SEQ_TRACE_TOKEN(p));
+                        ASSERT(code == ERTS_DSIG_SEND_OK);
+                    }
+                    erts_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
+                }
 		erts_destroy_dist_link(&dld);
 	    }
 	}
@@ -13756,12 +12913,11 @@ static void doit_exit_link(ErtsLink *lnk, void *vpcontext)
 	if(dep) {
 	    /* dist entries have node links in a separate structure to 
 	       avoid confusion */
-	    erts_smp_de_links_lock(dep);
+	    erts_de_links_lock(dep);
 	    rlnk = erts_remove_link(&(dep->node_links), p->common.id);
-	    erts_smp_de_links_unlock(dep);
+	    erts_de_links_unlock(dep);
 	    if (rlnk)
 		erts_destroy_link(rlnk);
-	    erts_deref_dist_entry(dep);
 	}
 	break;
 	
@@ -13781,7 +12937,7 @@ resume_suspend_monitor(ErtsSuspendMonitor *smon, void *vc_p)
 	ASSERT(suspendee != vc_p);
 	if (smon->active)
 	    resume_process(suspendee, ERTS_PROC_LOCK_STATUS);
-	erts_smp_proc_unlock(suspendee, ERTS_PROC_LOCK_STATUS);
+	erts_proc_unlock(suspendee, ERTS_PROC_LOCK_STATUS);
     }
     erts_destroy_suspend_monitor(smon);
 }
@@ -13810,18 +12966,13 @@ erts_do_exit_process(Process* p, Eterm reason)
 	erts_exit(ERTS_DUMP_EXIT, "System process %T terminated: %T\n",
                  p->common.id, reason);
 
-#ifdef ERTS_SMP
-    ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
+    ERTS_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
     /* By locking all locks (main lock is already locked) when going
        to exiting state (ERTS_PSFLG_EXITING), it is enough to take any lock when
        looking up a process (erts_pid2proc()) to prevent the looked up
        process from exiting until the lock has been released. */
-    erts_smp_proc_lock(p, ERTS_PROC_LOCKS_ALL_MINOR);
-#endif
+    erts_proc_lock(p, ERTS_PROC_LOCKS_ALL_MINOR);
 
-#ifndef ERTS_SMP
-    set_proc_self_exiting(p);
-#else
     if (ERTS_PSFLG_PENDING_EXIT & set_proc_self_exiting(p)) {
 	/* Process exited before pending exit was received... */
 	p->pending_exit.reason = THE_NON_VALUE;
@@ -13833,8 +12984,7 @@ erts_do_exit_process(Process* p, Eterm reason)
 
     cancel_suspend_of_suspendee(p, ERTS_PROC_LOCKS_ALL); 
 
-    ERTS_SMP_MSGQ_MV_INQ2PRIVQ(p);
-#endif
+    ERTS_MSGQ_MV_INQ2PRIVQ(p);
 
     if (IS_TRACED(p)) {
 	if (IS_TRACED_FL(p, F_TRACE_CALLS))
@@ -13853,7 +13003,7 @@ erts_do_exit_process(Process* p, Eterm reason)
 	ASSERT(erts_proc_read_refc(p) > 0);
     }
 
-    erts_smp_proc_unlock(p, ERTS_PROC_LOCKS_ALL_MINOR);
+    erts_proc_unlock(p, ERTS_PROC_LOCKS_ALL_MINOR);
 
     if (IS_TRACED_FL(p,F_TRACE_PROCS))
         trace_proc(p, ERTS_PROC_LOCK_MAIN, p, am_exit, reason);
@@ -13875,7 +13025,7 @@ erts_continue_exit_process(Process *p)
     ErtsMonitor *mon;
     ErtsProcLocks curr_locks = ERTS_PROC_LOCK_MAIN;
     Eterm reason = p->fvalue;
-    DistEntry *dep;
+    DistEntry *dep = NULL;
     erts_aint32_t state;
     int delay_del_proc = 0;
 
@@ -13883,7 +13033,7 @@ erts_continue_exit_process(Process *p)
     int yield_allowed = 1;
 #endif
 
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(p));
 
     ASSERT(ERTS_PROC_IS_EXITING(p));
 
@@ -13897,7 +13047,6 @@ erts_continue_exit_process(Process *p)
 	p->bif_timers = NULL;
     }
 
-#ifdef ERTS_SMP
     if (p->flags & F_SCHDLR_ONLN_WAITQ)
 	abort_sched_onln_chng_waitq(p);
 
@@ -13941,7 +13090,6 @@ erts_continue_exit_process(Process *p)
 		     __FILE__, __LINE__, (int) ssr);
 	}
     }
-#endif
 
     if (p->flags & F_USING_DB) {
 	if (erts_db_process_exiting(p, ERTS_PROC_LOCK_MAIN))
@@ -13950,24 +13098,20 @@ erts_continue_exit_process(Process *p)
     }
 
     erts_set_gc_state(p, 1);
-    state = erts_smp_atomic32_read_acqb(&p->state);
+    state = erts_atomic32_read_acqb(&p->state);
     if (state & ERTS_PSFLG_ACTIVE_SYS
-#ifdef ERTS_DIRTY_SCHEDULERS
         || p->dirty_sys_tasks
-#endif
         ) {
 	if (cleanup_sys_tasks(p, state, CONTEXT_REDS) >= CONTEXT_REDS/2)
 	    goto yield;
     }
 
 #ifdef DEBUG
-    erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
     ASSERT(p->sys_task_qs == NULL);
     ASSERT(ERTS_PROC_GET_DELAYED_GC_TASK_QS(p) == NULL);
-#ifdef ERTS_DIRTY_SCHEDULERS
     ASSERT(p->dirty_sys_tasks == NULL);
-#endif
-    erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+    erts_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
 #endif
 
     if (p->flags & F_USING_DDLL) {
@@ -14000,7 +13144,7 @@ erts_continue_exit_process(Process *p)
     if (IS_TRACED_FL(p, F_TRACE_SCHED_EXIT))
         trace_sched(p, curr_locks, am_out_exited);
 
-    erts_smp_proc_lock(p, ERTS_PROC_LOCKS_ALL_MINOR);
+    erts_proc_lock(p, ERTS_PROC_LOCKS_ALL_MINOR);
     curr_locks = ERTS_PROC_LOCKS_ALL;
 
     /*
@@ -14023,23 +13167,19 @@ erts_continue_exit_process(Process *p)
 	ErtsRunQueue *rq;
 	rq = erts_get_runq_current(erts_proc_sched_data(p));
 
-	erts_smp_runq_lock(rq);
+	erts_runq_lock(rq);
 
-#ifdef ERTS_SMP
 	ASSERT(p->scheduler_data);
 	ASSERT(p->scheduler_data->current_process == p);
 	ASSERT(p->scheduler_data->free_process == NULL);
 
 	p->scheduler_data->current_process = NULL;
 	p->scheduler_data->free_process = p;
-#else
-	erts_proc_inc_refc(p); /* Decremented in schedule() */
-#endif
 
 	/* Time of death! */
 	erts_ptab_delete_element(&erts_proc, &p->common);
 
-	erts_smp_runq_unlock(rq);
+	erts_runq_unlock(rq);
     }
 
     /*
@@ -14051,7 +13191,7 @@ erts_continue_exit_process(Process *p)
 
     {
 	/* Inactivate and notify free */
-	erts_aint32_t n, e, a = erts_smp_atomic32_read_nob(&p->state);
+	erts_aint32_t n, e, a = erts_atomic32_read_nob(&p->state);
 	int refc_inced = 0;
 	while (1) {
 	    n = e = a;
@@ -14062,12 +13202,11 @@ erts_continue_exit_process(Process *p)
 		erts_proc_inc_refc(p);
 		refc_inced = 1;
 	    }
-	    a = erts_smp_atomic32_cmpxchg_mb(&p->state, n, e);
+	    a = erts_atomic32_cmpxchg_mb(&p->state, n, e);
 	    if (a == e)
 		break;
 	}
 
-#ifdef ERTS_DIRTY_SCHEDULERS
         if (a & (ERTS_PSFLG_DIRTY_RUNNING
                  | ERTS_PSFLG_DIRTY_RUNNING_SYS)) {
 	    p->flags |= F_DELAYED_DEL_PROC;
@@ -14077,18 +13216,20 @@ erts_continue_exit_process(Process *p)
              * when done with the process...
 	     */
 	}
-#endif
 
 	if (refc_inced && !(n & ERTS_PSFLG_IN_RUNQ))
 	    erts_proc_dec_refc(p);
     }
-    
-    dep = (p->flags & F_DISTRIBUTION) ? erts_this_dist_entry : NULL;
 
-    erts_smp_proc_unlock(p, ERTS_PROC_LOCKS_ALL);
+    dep = ((p->flags & F_DISTRIBUTION)
+           ? ERTS_PROC_SET_DIST_ENTRY(p, NULL)
+           : NULL);
+
+    erts_proc_unlock(p, ERTS_PROC_LOCKS_ALL);
 
     if (dep) {
-	erts_do_net_exits(dep, reason);
+        erts_do_net_exits(dep, (reason == am_kill) ? am_killed : reason);
+        erts_deref_dist_entry(dep);
     }
 
     /*
@@ -14120,12 +13261,10 @@ erts_continue_exit_process(Process *p)
 								 have none here */
     }
 
-    erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
-    ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
+    erts_proc_lock(p, ERTS_PROC_LOCK_MAIN);
+    ERTS_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
 
-#ifdef ERTS_SMP
     erts_flush_trace_messages(p, ERTS_PROC_LOCK_MAIN);
-#endif
 
     ERTS_TRACER_CLEAR(&ERTS_TRACER(p));
 
@@ -14140,20 +13279,20 @@ erts_continue_exit_process(Process *p)
     ASSERT(yield_allowed);
 #endif
 
-    ERTS_SMP_LC_ASSERT(curr_locks == erts_proc_lc_my_proc_locks(p));
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & curr_locks);
+    ERTS_LC_ASSERT(curr_locks == erts_proc_lc_my_proc_locks(p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & curr_locks);
 
     p->i = (BeamInstr *) beam_continue_exit;
 
     if (!(curr_locks & ERTS_PROC_LOCK_STATUS)) {
-	erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+	erts_proc_lock(p, ERTS_PROC_LOCK_STATUS);
 	curr_locks |= ERTS_PROC_LOCK_STATUS;
     }
 
     if (curr_locks != ERTS_PROC_LOCK_MAIN)
-	erts_smp_proc_unlock(p, ~ERTS_PROC_LOCK_MAIN & curr_locks);
+	erts_proc_unlock(p, ~ERTS_PROC_LOCK_MAIN & curr_locks);
 
-    ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(p));
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(p));
 
     BUMP_ALL_REDS(p);
 }
@@ -14189,7 +13328,7 @@ erts_program_counter_info(fmtfn_t to, void *to_arg, Process *p)
     erts_print(to, to_arg, "CP: %p (", p->cp);
     print_function_from_pc(to, to_arg, p->cp);
     erts_print(to, to_arg, ")\n");
-    state = erts_smp_atomic32_read_acqb(&p->state);
+    state = erts_atomic32_read_acqb(&p->state);
     if (!(state & (ERTS_PSFLG_RUNNING
 		   | ERTS_PSFLG_RUNNING_SYS
 		   | ERTS_PSFLG_GC))) {
@@ -14270,8 +13409,7 @@ erts_print_scheduler_info(fmtfn_t to, void *to_arg, ErtsSchedulerData *esdp) {
 
     erts_print(to, to_arg, "=scheduler:%u\n", esdp->no);
 
-#ifdef ERTS_SMP
-    flg = erts_smp_atomic32_read_dirty(&esdp->ssi->flags);
+    flg = erts_atomic32_read_dirty(&esdp->ssi->flags);
     erts_print(to, to_arg, "Scheduler Sleep Info Flags: ");
     for (i = 0; i < ERTS_SSI_FLGS_MAX && flg; i++) {
         erts_aint32_t chk = (1 << i);
@@ -14298,7 +13436,6 @@ erts_print_scheduler_info(fmtfn_t to, void *to_arg, ErtsSchedulerData *esdp) {
         }
     }
     erts_print(to, to_arg, "\n");
-#endif
 
     flg = erts_atomic32_read_dirty(&esdp->ssi->aux_work);
     erts_print(to, to_arg, "Scheduler Sleep Info Aux Work: ");
@@ -14341,12 +13478,12 @@ erts_print_scheduler_info(fmtfn_t to, void *to_arg, ErtsSchedulerData *esdp) {
             break;
         }
         erts_print(to, to_arg, "Length: %d\n",
-                   erts_smp_atomic32_read_dirty(&esdp->run_queue->procs.prio_info[i].len));
+                   erts_atomic32_read_dirty(&esdp->run_queue->procs.prio_info[i].len));
     }
     erts_print(to, to_arg, "Run Queue Port Length: %d\n",
-               erts_smp_atomic32_read_dirty(&esdp->run_queue->ports.info.len));
+               erts_atomic32_read_dirty(&esdp->run_queue->ports.info.len));
 
-    flg = erts_smp_atomic32_read_dirty(&esdp->run_queue->flags);
+    flg = erts_atomic32_read_dirty(&esdp->run_queue->flags);
     erts_print(to, to_arg, "Run Queue Flags: ");
     for (i = 0; i < ERTS_RUNQ_FLG_MAX && flg; i++) {
         erts_aint32_t chk = (1 << i);
@@ -14418,7 +13555,7 @@ erts_print_scheduler_info(fmtfn_t to, void *to_arg, ErtsSchedulerData *esdp) {
     p = esdp->current_process;
     erts_print(to, to_arg, "Current Process: ");
     if (esdp->current_process && !(ERTS_TRACE_FLAGS(p) & F_SENSITIVE)) {
-	flg = erts_smp_atomic32_read_dirty(&p->state);
+	flg = erts_atomic32_read_dirty(&p->state);
 	erts_print(to, to_arg, "%T\n", p->common.id);
 
 	erts_print(to, to_arg, "Current Process State: ");
@@ -14468,19 +13605,17 @@ erts_print_scheduler_info(fmtfn_t to, void *to_arg, ErtsSchedulerData *esdp) {
  */
 void erts_halt(int code)
 {
-    if (-1 == erts_smp_atomic32_cmpxchg_acqb(&erts_halt_progress,
+    if (-1 == erts_atomic32_cmpxchg_acqb(&erts_halt_progress,
 					     erts_no_schedulers,
 					     -1)) {
-#ifdef ERTS_DIRTY_SCHEDULERS
         ERTS_RUNQ_FLGS_SET(ERTS_DIRTY_CPU_RUNQ, ERTS_RUNQ_FLG_HALTING);
         ERTS_RUNQ_FLGS_SET(ERTS_DIRTY_IO_RUNQ, ERTS_RUNQ_FLG_HALTING);
-#endif
 	erts_halt_code = code;
 	notify_reap_ports_relb();
     }
 }
 
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
 int
 erts_dbg_check_halloc_lock(Process *p)
 {
@@ -14500,3 +13635,24 @@ erts_dbg_check_halloc_lock(Process *p)
     return 0;
 }
 #endif
+
+void
+erts_debug_later_op_foreach(void (*callback)(void*),
+                            void (*func)(void *, ErtsThrPrgrVal, void *),
+                            void *arg)
+{
+    int six;
+    if (!erts_thr_progress_is_blocking())
+	ERTS_INTERNAL_ERROR("Not blocking thread progress");
+
+    for (six = 0; six < erts_no_schedulers; six++) {
+        ErtsSchedulerData *esdp = &erts_aligned_scheduler_data[six].esd;
+	ErtsThrPrgrLaterOp *lop = esdp->aux_work_data.later_op.first;
+
+        while (lop) {
+            if (lop->func == callback)
+                func(arg, lop->later, lop->data);
+            lop = lop->next;
+        }
+    }
+}
diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h
index 639818c20c..66d7848f89 100644
--- a/erts/emulator/beam/erl_process.h
+++ b/erts/emulator/beam/erl_process.h
@@ -47,7 +47,6 @@ typedef struct process Process;
 #include "erl_port.h"
 #undef ERL_PORT_GET_PORT_TYPE_ONLY__
 #include "erl_vm.h"
-#include "erl_smp.h"
 #include "erl_message.h"
 #include "erl_process_dict.h"
 #include "erl_node_container_utils.h"
@@ -106,27 +105,20 @@ struct saved_calls {
 };
 
 extern Export exp_send, exp_receive, exp_timeout;
-extern int erts_eager_check_io;
 extern int erts_sched_compact_load;
 extern int erts_sched_balance_util;
 extern Uint erts_no_schedulers;
 extern Uint erts_no_total_schedulers;
-#ifdef ERTS_DIRTY_SCHEDULERS
 extern Uint erts_no_dirty_cpu_schedulers;
 extern Uint erts_no_dirty_io_schedulers;
-#endif
 extern Uint erts_no_run_queues;
 extern int erts_sched_thread_suggested_stack_size;
-#ifdef ERTS_DIRTY_SCHEDULERS
 extern int erts_dcpu_sched_thread_suggested_stack_size;
 extern int erts_dio_sched_thread_suggested_stack_size;
-#endif
 #define ERTS_SCHED_THREAD_MIN_STACK_SIZE 20	/* Kilo words */
 #define ERTS_SCHED_THREAD_MAX_STACK_SIZE 8192	/* Kilo words */
 
-#ifdef ERTS_SMP
 #include "erl_bits.h"
-#endif
 
 /* process priorities */
 #define PRIORITY_MAX          0
@@ -224,31 +216,31 @@ extern int erts_dio_sched_thread_suggested_stack_size;
   ((FLGS) &= ~ERTS_RUNQ_FLG_EVACUATE((PRIO)))
 
 #define ERTS_RUNQ_FLGS_INIT(RQ, INIT)					\
-    erts_smp_atomic32_init_nob(&(RQ)->flags, (erts_aint32_t) (INIT))
+    erts_atomic32_init_nob(&(RQ)->flags, (erts_aint32_t) (INIT))
 #define ERTS_RUNQ_FLGS_SET(RQ, FLGS)					\
-    ((Uint32) erts_smp_atomic32_read_bor_relb(&(RQ)->flags,		\
+    ((Uint32) erts_atomic32_read_bor_relb(&(RQ)->flags,		\
 					      (erts_aint32_t) (FLGS)))
 #define ERTS_RUNQ_FLGS_SET_NOB(RQ, FLGS)				\
-    ((Uint32) erts_smp_atomic32_read_bor_nob(&(RQ)->flags,		\
+    ((Uint32) erts_atomic32_read_bor_nob(&(RQ)->flags,		\
 					     (erts_aint32_t) (FLGS)))
 #define ERTS_RUNQ_FLGS_BSET(RQ, MSK, FLGS)				\
-    ((Uint32) erts_smp_atomic32_read_bset_relb(&(RQ)->flags,		\
+    ((Uint32) erts_atomic32_read_bset_relb(&(RQ)->flags,		\
 					       (erts_aint32_t) (MSK),	\
 					       (erts_aint32_t) (FLGS)))
 #define ERTS_RUNQ_FLGS_UNSET(RQ, FLGS)					\
-    ((Uint32) erts_smp_atomic32_read_band_relb(&(RQ)->flags,		\
+    ((Uint32) erts_atomic32_read_band_relb(&(RQ)->flags,		\
 					       (erts_aint32_t) ~(FLGS)))
 #define ERTS_RUNQ_FLGS_UNSET_NOB(RQ, FLGS)					\
-    ((Uint32) erts_smp_atomic32_read_band_nob(&(RQ)->flags,		\
+    ((Uint32) erts_atomic32_read_band_nob(&(RQ)->flags,		\
 					      (erts_aint32_t) ~(FLGS)))
 #define ERTS_RUNQ_FLGS_GET(RQ)						\
-    ((Uint32) erts_smp_atomic32_read_acqb(&(RQ)->flags))
+    ((Uint32) erts_atomic32_read_acqb(&(RQ)->flags))
 #define ERTS_RUNQ_FLGS_GET_NOB(RQ)					\
-    ((Uint32) erts_smp_atomic32_read_nob(&(RQ)->flags))
+    ((Uint32) erts_atomic32_read_nob(&(RQ)->flags))
 #define ERTS_RUNQ_FLGS_GET_MB(RQ)					\
-    ((Uint32) erts_smp_atomic32_read_mb(&(RQ)->flags))
+    ((Uint32) erts_atomic32_read_mb(&(RQ)->flags))
 #define ERTS_RUNQ_FLGS_READ_BSET(RQ, MSK, FLGS)		  		\
-    ((Uint32) erts_smp_atomic32_read_bset_relb(&(RQ)->flags, 		\
+    ((Uint32) erts_atomic32_read_bset_relb(&(RQ)->flags, 		\
 					       (erts_aint32_t) (MSK),	\
 					       (erts_aint32_t) (FLGS)))
 
@@ -365,20 +357,18 @@ typedef enum {
 
 typedef struct ErtsSchedulerSleepInfo_ ErtsSchedulerSleepInfo;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 typedef struct {
-    erts_smp_spinlock_t lock;
+    erts_spinlock_t lock;
     ErtsSchedulerSleepInfo *list;
 } ErtsSchedulerSleepList;
-#endif
 
 struct ErtsSchedulerSleepInfo_ {
-#ifdef ERTS_SMP
+    struct ErtsSchedulerData_ *esdp;
     ErtsSchedulerSleepInfo *next;
     ErtsSchedulerSleepInfo *prev;
-    erts_smp_atomic32_t flags;
+    erts_atomic32_t flags;
     erts_tse_t *event;
-#endif
+    struct erts_poll_thread *psi;
     erts_atomic32_t aux_work;
 };
 
@@ -422,7 +412,7 @@ typedef struct ErtsSchedulerData_ ErtsSchedulerData;
 typedef struct ErtsRunQueue_ ErtsRunQueue;
 
 typedef struct {
-    erts_smp_atomic32_t len;
+    erts_atomic32_t len;
     erts_aint32_t max_len;
     int reds;
 } ErtsRunQueueInfo;
@@ -433,7 +423,6 @@ typedef struct {
 #  define ERTS_HAVE_SCHED_UTIL_BALANCING_SUPPORT_OPT 1
 #endif
 
-#ifdef ERTS_SMP
 
 #undef ERTS_HAVE_SCHED_UTIL_BALANCING_SUPPORT
 #define ERTS_HAVE_SCHED_UTIL_BALANCING_SUPPORT ERTS_HAVE_SCHED_UTIL_BALANCING_SUPPORT_OPT
@@ -476,30 +465,25 @@ struct ErtsMigrationPaths_ {
     ErtsMigrationPath mpath[1];
 };
 
-#endif /* ERTS_SMP */
 
 struct ErtsRunQueue_ {
     int ix;
 
-    erts_smp_mtx_t mtx;
-    erts_smp_cnd_t cnd;
+    erts_mtx_t mtx;
+    erts_cnd_t cnd;
 
-#ifdef ERTS_DIRTY_SCHEDULERS
-#ifdef ERTS_SMP
     ErtsSchedulerSleepList sleepers;
-#endif
-#endif
 
     ErtsSchedulerData *scheduler;
     int waiting; /* < 0 in sys schedule; > 0 on cnd variable */
     int woken;
-    erts_smp_atomic32_t flags;
+    erts_atomic32_t flags;
     int check_balance_reds;
     int full_reds_history_sum;
     int full_reds_history[ERTS_FULL_REDS_HISTORY_SIZE];
     int out_of_work_count;
     erts_aint32_t max_len;
-    erts_smp_atomic32_t len;
+    erts_atomic32_t len;
     int wakeup_other;
     int wakeup_other_reds;
 
@@ -518,7 +502,7 @@ struct ErtsRunQueue_ {
     struct {
 	ErtsMiscOpList *start;
 	ErtsMiscOpList *end;
-	erts_smp_atomic_t evac_runq;
+	erts_atomic_t evac_runq;
     } misc;
 
     struct {
@@ -531,9 +515,7 @@ struct ErtsRunQueue_ {
 #endif
 };
 
-#ifdef ERTS_SMP
 extern long erts_runq_supervision_interval;
-#endif
 
 typedef union {
     ErtsRunQueue runq;
@@ -581,17 +563,12 @@ typedef struct {
     int sched_id;
     ErtsSchedulerData *esdp;
     ErtsSchedulerSleepInfo *ssi;
-#ifdef ERTS_SMP
     ErtsThrPrgrVal current_thr_prgr;
     ErtsThrPrgrVal latest_wakeup;
-#endif
     struct {
 	int ix;
-#ifdef ERTS_SMP
 	ErtsThrPrgrVal thr_prgr;
-#endif
     } misc;
-#ifdef ERTS_SMP
     struct {
 	ErtsThrPrgrVal thr_prgr;
     } dd;
@@ -604,24 +581,17 @@ typedef struct {
 	ErtsThrPrgrLaterOp *first;
 	ErtsThrPrgrLaterOp *last;
     } later_op;
-#endif
-#ifdef ERTS_USE_ASYNC_READY_Q
     struct {
-#ifdef ERTS_SMP
 	int need_thr_prgr;
 	ErtsThrPrgrVal thr_prgr;
-#endif
 	void *queue;
     } async_ready;
-#endif
-#ifdef ERTS_SMP
     struct {
 	Uint64 next;
 	int *sched2jix;
 	int jix;
 	ErtsDelayedAuxWorkWakeupJob *job;
     } delayed_wakeup;
-#endif
     struct {
         ErtsEtsAllYieldData ets_all;
         /* Other yielding operations... */
@@ -639,13 +609,11 @@ typedef struct {
     (&(ESDP)->aux_work_data.yield.NAME)
 void erts_notify_new_aux_yield_work(ErtsSchedulerData *esdp);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 typedef enum {
     ERTS_DIRTY_CPU_SCHEDULER,
     ERTS_DIRTY_IO_SCHEDULER
 } ErtsDirtySchedulerType;
 
-#endif
 
 struct ErtsSchedulerData_ {
     /*
@@ -659,21 +627,17 @@ struct ErtsSchedulerData_ {
     ErtsTimerWheel *timer_wheel;
     ErtsNextTimeoutRef next_tmo_ref;
     ErtsHLTimerService *timer_service;
-#ifdef ERTS_SMP
     ethr_tid tid;		/* Thread id */
     struct erl_bits_state erl_bits_state; /* erl_bits.c state */
     void *match_pseudo_process; /* erl_db_util.c:db_prog_match() */
     Process *free_process;
     ErtsThrPrgrData thr_progress_data;
-#endif
     ErtsSchedulerSleepInfo *ssi;
     Process *current_process;
     ErtsSchedType type;
     Uint no;			/* Scheduler number for normal schedulers */
-#ifdef ERTS_DIRTY_SCHEDULERS
     Uint dirty_no;  /* Scheduler number for dirty schedulers */
     Process *dirty_shadow_process;
-#endif
     Port *current_port;
     ErtsRunQueue *run_queue;
     int virtual_reds;
@@ -712,25 +676,23 @@ typedef union {
 } ErtsAlignedSchedulerData;
 
 extern ErtsAlignedSchedulerData *erts_aligned_scheduler_data;
-#ifdef ERTS_DIRTY_SCHEDULERS
 extern ErtsAlignedSchedulerData *erts_aligned_dirty_cpu_scheduler_data;
 extern ErtsAlignedSchedulerData *erts_aligned_dirty_io_scheduler_data;
-#endif
 
-#ifndef ERTS_SMP
-extern ErtsSchedulerData *erts_scheduler_data;
-#endif
 
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
-int erts_smp_lc_runq_is_locked(ErtsRunQueue *);
+#if defined(ERTS_ENABLE_LOCK_CHECK)
+int erts_lc_runq_is_locked(ErtsRunQueue *);
 #endif
 
+void
+erts_debug_later_op_foreach(void (*callback)(void*),
+                            void (*func)(void *, ErtsThrPrgrVal, void *),
+                            void *arg);
+
 #ifdef ERTS_INCLUDE_SCHEDULER_INTERNALS
 
-#ifdef ERTS_SMP
 void erts_empty_runq(ErtsRunQueue *rq);
 void erts_non_empty_runq(ErtsRunQueue *rq);
-#endif
 
 
 /*
@@ -738,86 +700,84 @@ void erts_non_empty_runq(ErtsRunQueue *rq);
  * other threads peek at values without run queue lock.
  */
 
-ERTS_GLB_INLINE void erts_smp_inc_runq_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi, int prio);
-ERTS_GLB_INLINE void erts_smp_dec_runq_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi, int prio);
-ERTS_GLB_INLINE void erts_smp_reset_max_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi);
+ERTS_GLB_INLINE void erts_inc_runq_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi, int prio);
+ERTS_GLB_INLINE void erts_dec_runq_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi, int prio);
+ERTS_GLB_INLINE void erts_reset_max_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
 ERTS_GLB_INLINE void
-erts_smp_inc_runq_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi, int prio)
+erts_inc_runq_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi, int prio)
 {
     erts_aint32_t len;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
 
-    len = erts_smp_atomic32_read_dirty(&rq->len);
+    len = erts_atomic32_read_dirty(&rq->len);
 
-#ifdef ERTS_SMP
     if (len == 0)
 	erts_non_empty_runq(rq);
-#endif
     len++;
     if (rq->max_len < len)
 	rq->max_len = len;
     ASSERT(len > 0);
-    erts_smp_atomic32_set_nob(&rq->len, len);
+    erts_atomic32_set_nob(&rq->len, len);
 
-    len = erts_smp_atomic32_read_dirty(&rqi->len);
+    len = erts_atomic32_read_dirty(&rqi->len);
     ASSERT(len >= 0);
     if (len == 0) {
-	ASSERT((erts_smp_atomic32_read_nob(&rq->flags)
+	ASSERT((erts_atomic32_read_nob(&rq->flags)
 		& ((erts_aint32_t) (1 << prio))) == 0);
-	erts_smp_atomic32_read_bor_nob(&rq->flags,
+	erts_atomic32_read_bor_nob(&rq->flags,
 				       (erts_aint32_t) (1 << prio));
     }
     len++;
     if (rqi->max_len < len)
 	rqi->max_len = len;
 
-    erts_smp_atomic32_set_relb(&rqi->len, len);
+    erts_atomic32_set_relb(&rqi->len, len);
 }
 
 ERTS_GLB_INLINE void
-erts_smp_dec_runq_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi, int prio)
+erts_dec_runq_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi, int prio)
 {
     erts_aint32_t len;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
 
-    len = erts_smp_atomic32_read_dirty(&rq->len);
+    len = erts_atomic32_read_dirty(&rq->len);
     len--;
     ASSERT(len >= 0);
-    erts_smp_atomic32_set_nob(&rq->len, len);
+    erts_atomic32_set_nob(&rq->len, len);
 
-    len = erts_smp_atomic32_read_dirty(&rqi->len);
+    len = erts_atomic32_read_dirty(&rqi->len);
     len--;
     ASSERT(len >= 0);
     if (len == 0) {
-	ASSERT((erts_smp_atomic32_read_nob(&rq->flags)
+	ASSERT((erts_atomic32_read_nob(&rq->flags)
 		& ((erts_aint32_t) (1 << prio))));
-	erts_smp_atomic32_read_band_nob(&rq->flags,
+	erts_atomic32_read_band_nob(&rq->flags,
 					~((erts_aint32_t) (1 << prio)));
     }
-    erts_smp_atomic32_set_relb(&rqi->len, len);
+    erts_atomic32_set_relb(&rqi->len, len);
 
 }
 
 ERTS_GLB_INLINE void
-erts_smp_reset_max_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi)
+erts_reset_max_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi)
 {
     erts_aint32_t len;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(rq));
+    ERTS_LC_ASSERT(erts_lc_runq_is_locked(rq));
 
-    len = erts_smp_atomic32_read_dirty(&rqi->len);
+    len = erts_atomic32_read_dirty(&rqi->len);
     ASSERT(rqi->max_len >= len);
     rqi->max_len = len;
 }
 
 #endif /* ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
-#define RUNQ_READ_LEN(X) erts_smp_atomic32_read_nob((X))
+#define RUNQ_READ_LEN(X) erts_atomic32_read_nob((X))
 
 #endif /* ERTS_INCLUDE_SCHEDULER_INTERNALS */
 
@@ -835,14 +795,15 @@ erts_smp_reset_max_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi)
 #define ERTS_PSD_NIF_TRAP_EXPORT		5
 #define ERTS_PSD_ETS_OWNED_TABLES               6
 #define ERTS_PSD_ETS_FIXED_TABLES               7
-#define ERTS_PSD_SUSPENDED_SAVED_CALLS_BUF	8
+#define ERTS_PSD_DIST_ENTRY	                8
+#define ERTS_PSD_SUSPENDED_SAVED_CALLS_BUF	9 /* keep last... */
 
-#define ERTS_PSD_SIZE				9
+#define ERTS_PSD_SIZE				10
 
 #if !defined(HIPE)
 #  undef ERTS_PSD_SUSPENDED_SAVED_CALLS_BUF
 #  undef ERTS_PSD_SIZE
-#  define ERTS_PSD_SIZE 8
+#  define ERTS_PSD_SIZE 9
 #endif
 
 typedef struct {
@@ -876,6 +837,9 @@ typedef struct {
 #define ERTS_PSD_ETS_FIXED_TABLES_GET_LOCKS ERTS_PROC_LOCK_MAIN
 #define ERTS_PSD_ETS_FIXED_TABLES_SET_LOCKS ERTS_PROC_LOCK_MAIN
 
+#define ERTS_PSD_DIST_ENTRY_GET_LOCKS ERTS_PROC_LOCK_MAIN
+#define ERTS_PSD_DIST_ENTRY_SET_LOCKS ERTS_PROC_LOCK_MAIN
+
 typedef struct {
     ErtsProcLocks get_locks;
     ErtsProcLocks set_locks;
@@ -890,7 +854,7 @@ extern ErtsLcPSDLocks erts_psd_required_locks[ERTS_PSD_SIZE];
 #define ERTS_SCHED_STAT_MODIFY_CLEAR		3
 
 typedef struct {
-    erts_smp_spinlock_t lock;
+    erts_spinlock_t lock;
     int enabled;
     struct {
 	Eterm name;
@@ -911,7 +875,6 @@ typedef struct {
 typedef struct ErtsProcSysTask_ ErtsProcSysTask;
 typedef struct ErtsProcSysTaskQs_ ErtsProcSysTaskQs;
 
-#ifdef ERTS_SMP
 
 typedef struct ErtsPendingSuspend_ ErtsPendingSuspend;
 struct ErtsPendingSuspend_ {
@@ -924,7 +887,6 @@ struct ErtsPendingSuspend_ {
 			Eterm pid);
 };
 
-#endif
 
 
 /* Defines to ease the change of memory architecture */
@@ -1076,23 +1038,18 @@ struct process {
     ErlHeapFragment* live_hf_end;
     ErtsMessage *msg_frag;	/* Pointer to message fragment list */
     Uint mbuf_sz;		/* Total size of heap fragments and message fragments */
-    erts_smp_atomic_t psd;		/* Rarely used process specific data */
+    erts_atomic_t psd;		/* Rarely used process specific data */
 
     Uint64 bin_vheap_sz;	/* Virtual heap block size for binaries */
     Uint64 bin_old_vheap_sz;	/* Virtual old heap block size for binaries */
     Uint64 bin_old_vheap;	/* Virtual old heap size for binaries */
 
     ErtsProcSysTaskQs *sys_task_qs;
-#ifdef ERTS_DIRTY_SCHEDULERS
     ErtsProcSysTask *dirty_sys_tasks;
-#endif
 
-    erts_smp_atomic32_t state;  /* Process state flags (see ERTS_PSFLG_*) */
-#ifdef ERTS_DIRTY_SCHEDULERS
-    erts_smp_atomic32_t dirty_state; /* Process dirty state flags (see ERTS_PDSFLG_*) */
-#endif
+    erts_atomic32_t state;  /* Process state flags (see ERTS_PSFLG_*) */
+    erts_atomic32_t dirty_state; /* Process dirty state flags (see ERTS_PDSFLG_*) */
 
-#ifdef ERTS_SMP
     ErlMessageInQueue msg_inq;
     ErlTraceMessageQueue *trace_msg_q;
     ErtsPendExit pending_exit;
@@ -1100,11 +1057,10 @@ struct process {
     ErtsSchedulerData *scheduler_data;
     Eterm suspendee;
     ErtsPendingSuspend *pending_suspenders;
-    erts_smp_atomic_t run_queue;
+    erts_atomic_t run_queue;
 #ifdef HIPE
     struct hipe_process_state_smp hipe_smp;
 #endif
-#endif
 
 #ifdef CHECK_FOR_HOLES
     Eterm* last_htop;		/* No need to scan the heap below this point. */
@@ -1249,7 +1205,6 @@ void erts_check_for_holes(Process* p);
 #define ERTS_PSFLGS_GET_PRQ_PRIO(PSFLGS) \
     (((PSFLGS) >> ERTS_PSFLGS_PRQ_PRIO_OFFSET) & ERTS_PSFLGS_PRIO_MASK)
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 
 /*
  * Flags in the dirty_state field.
@@ -1276,7 +1231,6 @@ void erts_check_for_holes(Process* p);
 					 | ERTS_PDSFLG_IN_CPU_PRQ_HIGH	\
 					 | ERTS_PDSFLG_IN_CPU_PRQ_NORMAL\
 					 | ERTS_PDSFLG_IN_CPU_PRQ_LOW)
-#endif
 
 
 /*
@@ -1367,7 +1321,7 @@ Eterm* erts_heap_alloc(Process* p, Uint need, Uint xtra);
 Eterm* erts_set_hole_marker(Eterm* ptr, Uint sz);
 #endif
 
-extern erts_smp_rwmtx_t erts_cpu_bind_rwmtx;
+extern erts_rwmtx_t erts_cpu_bind_rwmtx;
 /* If any of the erts_system_monitor_* variables are set (enabled),
 ** erts_system_monitor must be != NIL, to allow testing on just
 ** the erts_system_monitor_* variables.
@@ -1541,20 +1495,14 @@ extern int erts_system_profile_ts_type;
 	}						\
     } while (0)
 
-#if defined(ERTS_DIRTY_SCHEDULERS) && defined(ERTS_SMP)
 #define ERTS_NUM_DIRTY_CPU_RUNQS 1
 #define ERTS_NUM_DIRTY_IO_RUNQS 1
-#else
-#define ERTS_NUM_DIRTY_CPU_RUNQS 0
-#define ERTS_NUM_DIRTY_IO_RUNQS 0
-#endif
 
 #define ERTS_NUM_DIRTY_RUNQS (ERTS_NUM_DIRTY_CPU_RUNQS+ERTS_NUM_DIRTY_IO_RUNQS)
 
 #define ERTS_RUNQ_IX(IX)						\
   (ASSERT(0 <= (IX) && (IX) < erts_no_run_queues+ERTS_NUM_DIRTY_RUNQS), \
    &erts_aligned_run_queues[(IX)].runq)
-#ifdef ERTS_DIRTY_SCHEDULERS
 #define ERTS_RUNQ_IX_IS_DIRTY(IX)					\
   (ASSERT(0 <= (IX) && (IX) < erts_no_run_queues+ERTS_NUM_DIRTY_RUNQS), \
    (erts_no_run_queues <= (IX)))
@@ -1565,13 +1513,9 @@ extern int erts_system_profile_ts_type;
 #define ERTS_DIRTY_IO_RUNQ  (&erts_aligned_run_queues[erts_no_run_queues+1].runq)
 #define ERTS_RUNQ_IS_DIRTY_CPU_RUNQ(RQ) ((RQ) == ERTS_DIRTY_CPU_RUNQ)
 #define ERTS_RUNQ_IS_DIRTY_IO_RUNQ(RQ) ((RQ) == ERTS_DIRTY_IO_RUNQ)
-#else
-#define ERTS_RUNQ_IX_IS_DIRTY(IX) 0
-#endif
 #define ERTS_SCHEDULER_IX(IX)						\
   (ASSERT(0 <= (IX) && (IX) < erts_no_schedulers),			\
    &erts_aligned_scheduler_data[(IX)].esd)
-#ifdef ERTS_DIRTY_SCHEDULERS
 #define ERTS_DIRTY_CPU_SCHEDULER_IX(IX)					\
   (ASSERT(0 <= (IX) && (IX) < erts_no_dirty_cpu_schedulers),		\
    &erts_aligned_dirty_cpu_scheduler_data[(IX)].esd)
@@ -1584,24 +1528,12 @@ extern int erts_system_profile_ts_type;
     ((ESDP)->type == ERTS_SCHED_DIRTY_CPU)
 #define ERTS_SCHEDULER_IS_DIRTY_IO(ESDP)				\
     ((ESDP)->type == ERTS_SCHED_DIRTY_IO)
-#else /* !ERTS_DIRTY_SCHEDULERS */
-#define ERTS_RUNQ_IX_IS_DIRTY(IX) 0
-#define ERTS_SCHEDULER_IS_DIRTY(ESDP) 0
-#define ERTS_SCHEDULER_IS_DIRTY_CPU(ESDP) 0
-#define ERTS_SCHEDULER_IS_DIRTY_IO(ESDP) 0
-#endif
 
 void erts_pre_init_process(void);
 void erts_late_init_process(void);
 void erts_early_init_scheduling(int);
-void erts_init_scheduling(int, int
-#ifdef ERTS_DIRTY_SCHEDULERS
-			  , int, int, int
-#endif
-			  );
-#ifdef ERTS_DIRTY_SCHEDULERS
+void erts_init_scheduling(int, int, int, int, int, int);
 void erts_execute_dirty_system_task(Process *c_p);
-#endif
 int erts_set_gc_state(Process *c_p, int enable);
 Eterm erts_sched_wall_time_request(Process *c_p, int set, int enable,
                                    int dirty_cpu, int want_dirty_io);
@@ -1799,14 +1731,11 @@ void erts_schedule_ets_free_fixation(Eterm pid, struct db_fixation*);
 void erts_schedule_flush_trace_messages(Process *proc, int force_on_proc);
 int erts_flush_trace_messages(Process *c_p, ErtsProcLocks locks);
 
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
 int erts_dbg_check_halloc_lock(Process *p);
 #endif
-#if defined(ERTS_SMP) || defined(ERTS_DIRTY_SCHEDULERS)
 void
 erts_schedulers_state(Uint *, Uint *, Uint *, Uint *, Uint *, Uint *, Uint *, Uint *);
-#endif
-#ifdef ERTS_SMP
 ErtsSchedSuspendResult
 erts_set_schedulers_online(Process *p,
 			   ErtsProcLocks plocks,
@@ -1821,14 +1750,9 @@ void erts_start_schedulers(void);
 void erts_alloc_notify_delayed_dealloc(int);
 void erts_alloc_ensure_handle_delayed_dealloc_call(int);
 void erts_notify_canceled_timer(ErtsSchedulerData *, int);
-#endif
-#if ERTS_USE_ASYNC_READY_Q
 void erts_notify_check_async_ready_queue(void *);
-#endif
-#ifdef ERTS_SMP
 void erts_notify_code_ix_activation(Process* p, ErtsThrPrgrVal later);
 void erts_notify_finish_breakpointing(Process* p);
-#endif
 void erts_schedule_misc_aux_work(int sched_id,
 				 void (*func)(void *),
 				 void *arg);
@@ -1897,13 +1821,9 @@ int erts_send_exit_signal(Process *,
 			  Eterm,
 			  Process *,
 			  Uint32);
-#ifdef ERTS_SMP
 void erts_handle_pending_exit(Process *, ErtsProcLocks);
 #define ERTS_PROC_PENDING_EXIT(P) \
-    (ERTS_PSFLG_PENDING_EXIT & erts_smp_atomic32_read_acqb(&(P)->state))
-#else
-#define ERTS_PROC_PENDING_EXIT(P) 0
-#endif
+    (ERTS_PSFLG_PENDING_EXIT & erts_atomic32_read_acqb(&(P)->state))
 
 void erts_deep_process_dump(fmtfn_t, void *);
 
@@ -1933,19 +1853,7 @@ do {										\
 #  define ERTS_VERIFY_UNUSED_TEMP_ALLOC(ESDP)
 #endif
 
-#if defined(ERTS_SMP) || defined(USE_THREADS)
 ErtsSchedulerData *erts_get_scheduler_data(void);
-#else
-ERTS_GLB_INLINE ErtsSchedulerData *erts_get_scheduler_data(void);
-#if ERTS_GLB_INLINE_INCL_FUNC_DEF
-
-ERTS_GLB_INLINE
-ErtsSchedulerData *erts_get_scheduler_data(void)
-{
-    return erts_scheduler_data;
-}
-#endif
-#endif
 
 void erts_schedule_process(Process *, erts_aint32_t, ErtsProcLocks);
 
@@ -1957,7 +1865,7 @@ ERTS_GLB_INLINE void
 erts_proc_notify_new_message(Process *p, ErtsProcLocks locks)
 {
     /* No barrier needed, due to msg lock */
-    erts_aint32_t state = erts_smp_atomic32_read_nob(&p->state);
+    erts_aint32_t state = erts_atomic32_read_nob(&p->state);
     if (!(state & ERTS_PSFLG_ACTIVE))
 	erts_schedule_process(p, state, locks);
 }
@@ -1967,7 +1875,7 @@ erts_schedule_dirty_sys_execution(Process *c_p)
 {
     erts_aint32_t a, n, e;
 
-    a = erts_smp_atomic32_read_nob(&c_p->state);
+    a = erts_atomic32_read_nob(&c_p->state);
 
     /*
      * Only a currently executing process schedules
@@ -1983,7 +1891,7 @@ erts_schedule_dirty_sys_execution(Process *c_p)
                   | ERTS_PSFLG_PENDING_EXIT))) {
         e = a;
         n = a | ERTS_PSFLG_DIRTY_ACTIVE_SYS;
-        a = erts_smp_atomic32_cmpxchg_mb(&c_p->state, n, e);
+        a = erts_atomic32_cmpxchg_mb(&c_p->state, n, e);
         if (a == e)
             break; /* dirty-active-sys set */
     }
@@ -1991,21 +1899,21 @@ erts_schedule_dirty_sys_execution(Process *c_p)
 
 #endif
 
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
 
 #define ERTS_PROCESS_LOCK_ONLY_LOCK_CHECK_PROTO__
 #include "erl_process_lock.h"
 #undef ERTS_PROCESS_LOCK_ONLY_LOCK_CHECK_PROTO__
 
-#define ERTS_SMP_LC_CHK_RUNQ_LOCK(RQ, L)				\
+#define ERTS_LC_CHK_RUNQ_LOCK(RQ, L)				\
 do {									\
     if ((L))								\
-	ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked((RQ)));		\
+	ERTS_LC_ASSERT(erts_lc_runq_is_locked((RQ)));		\
     else								\
-	ERTS_SMP_LC_ASSERT(!erts_smp_lc_runq_is_locked((RQ)));		\
+	ERTS_LC_ASSERT(!erts_lc_runq_is_locked((RQ)));		\
 } while (0)
 #else
-#define ERTS_SMP_LC_CHK_RUNQ_LOCK(RQ, L)
+#define ERTS_LC_CHK_RUNQ_LOCK(RQ, L)
 #endif
 
 void *erts_psd_set_init(Process *p, int ix, void *data);
@@ -2021,22 +1929,22 @@ ERTS_GLB_INLINE void *
 erts_psd_get(Process *p, int ix)
 {
     ErtsPSD *psd;
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     ErtsProcLocks locks = erts_proc_lc_my_proc_locks(p);
     if (ERTS_LC_PSD_ANY_LOCK == erts_psd_required_locks[ix].get_locks)
-	ERTS_SMP_LC_ASSERT(locks || erts_thr_progress_is_blocking());
+	ERTS_LC_ASSERT(locks || erts_thr_progress_is_blocking());
     else {
 	locks &= erts_psd_required_locks[ix].get_locks;
-	ERTS_SMP_LC_ASSERT(erts_psd_required_locks[ix].get_locks == locks
+	ERTS_LC_ASSERT(erts_psd_required_locks[ix].get_locks == locks
 			   || erts_thr_progress_is_blocking());
     }
 #endif
 
-    psd = (ErtsPSD *) erts_smp_atomic_read_nob(&p->psd);
+    psd = (ErtsPSD *) erts_atomic_read_nob(&p->psd);
     ASSERT(0 <= ix && ix < ERTS_PSD_SIZE);
     if (!psd)
 	return NULL;
-    ERTS_SMP_DATA_DEPENDENCY_READ_MEMORY_BARRIER;
+    ERTS_THR_DATA_DEPENDENCY_READ_MEMORY_BARRIER;
     return psd->data[ix];
 }
 
@@ -2044,30 +1952,28 @@ ERTS_GLB_INLINE void *
 erts_psd_set(Process *p, int ix, void *data)
 {
     ErtsPSD *psd;
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     ErtsProcLocks locks = erts_proc_lc_my_proc_locks(p);
-    erts_aint32_t state = state = erts_smp_atomic32_read_nob(&p->state);
+    erts_aint32_t state = state = erts_atomic32_read_nob(&p->state);
     if (!(state & ERTS_PSFLG_FREE)) {
 	if (ERTS_LC_PSD_ANY_LOCK == erts_psd_required_locks[ix].set_locks)
-	    ERTS_SMP_LC_ASSERT(locks || erts_thr_progress_is_blocking());
+	    ERTS_LC_ASSERT(locks || erts_thr_progress_is_blocking());
 	else {
 	    locks &= erts_psd_required_locks[ix].set_locks;
-	    ERTS_SMP_LC_ASSERT(erts_psd_required_locks[ix].set_locks == locks
+	    ERTS_LC_ASSERT(erts_psd_required_locks[ix].set_locks == locks
 			       || erts_thr_progress_is_blocking());
 	}
     }
 #endif
-    psd = (ErtsPSD *) erts_smp_atomic_read_nob(&p->psd);
+    psd = (ErtsPSD *) erts_atomic_read_nob(&p->psd);
     ASSERT(0 <= ix && ix < ERTS_PSD_SIZE);
     if (psd) {
 	void *old;
-#ifdef ERTS_SMP
 #ifdef ETHR_ORDERED_READ_DEPEND
 	ETHR_MEMBAR(ETHR_LoadStore|ETHR_StoreStore);
 #else
 	ETHR_MEMBAR(ETHR_LoadLoad|ETHR_LoadStore|ETHR_StoreStore);
 #endif
-#endif
 	old = psd->data[ix];
 	psd->data[ix] = data;
 	return old;
@@ -2104,6 +2010,11 @@ erts_psd_set(Process *p, int ix, void *data)
 #define ERTS_PROC_SET_NIF_TRAP_EXPORT(P, NTE) \
     erts_psd_set((P), ERTS_PSD_NIF_TRAP_EXPORT, (void *) (NTE))
 
+#define ERTS_PROC_GET_DIST_ENTRY(P) \
+    ((DistEntry *) erts_psd_get((P), ERTS_PSD_DIST_ENTRY))
+#define ERTS_PROC_SET_DIST_ENTRY(P, DE) \
+    ((DistEntry *) erts_psd_set((P), ERTS_PSD_DIST_ENTRY, (void *) (DE)))
+
 #ifdef HIPE
 #define ERTS_PROC_GET_SUSPENDED_SAVED_CALLS_BUF(P) \
   ((struct saved_calls *) erts_psd_get((P), ERTS_PSD_SUSPENDED_SAVED_CALLS_BUF))
@@ -2147,7 +2058,6 @@ erts_proc_set_error_handler(Process *p, Eterm handler)
 
 #ifdef ERTS_INCLUDE_SCHEDULER_INTERNALS
 
-#ifdef ERTS_SMP
 
 #include "erl_thr_progress.h"
 
@@ -2249,7 +2159,6 @@ erts_check_emigration_need(ErtsRunQueue *c_rq, int prio)
 
 #endif
 
-#endif
 
 #endif
 
@@ -2260,13 +2169,13 @@ ERTS_GLB_INLINE Eterm erts_get_current_pid(void);
 ERTS_GLB_INLINE Uint erts_get_scheduler_id(void);
 ERTS_GLB_INLINE ErtsRunQueue *erts_get_runq_proc(Process *p);
 ERTS_GLB_INLINE ErtsRunQueue *erts_get_runq_current(ErtsSchedulerData *esdp);
-ERTS_GLB_INLINE void erts_smp_runq_lock(ErtsRunQueue *rq);
-ERTS_GLB_INLINE int erts_smp_runq_trylock(ErtsRunQueue *rq);
-ERTS_GLB_INLINE void erts_smp_runq_unlock(ErtsRunQueue *rq);
-ERTS_GLB_INLINE void erts_smp_xrunq_lock(ErtsRunQueue *rq, ErtsRunQueue *xrq);
-ERTS_GLB_INLINE void erts_smp_xrunq_unlock(ErtsRunQueue *rq, ErtsRunQueue *xrq);
-ERTS_GLB_INLINE void erts_smp_runqs_lock(ErtsRunQueue *rq1, ErtsRunQueue *rq2);
-ERTS_GLB_INLINE void erts_smp_runqs_unlock(ErtsRunQueue *rq1, ErtsRunQueue *rq2);
+ERTS_GLB_INLINE void erts_runq_lock(ErtsRunQueue *rq);
+ERTS_GLB_INLINE int erts_runq_trylock(ErtsRunQueue *rq);
+ERTS_GLB_INLINE void erts_runq_unlock(ErtsRunQueue *rq);
+ERTS_GLB_INLINE void erts_xrunq_lock(ErtsRunQueue *rq, ErtsRunQueue *xrq);
+ERTS_GLB_INLINE void erts_xrunq_unlock(ErtsRunQueue *rq, ErtsRunQueue *xrq);
+ERTS_GLB_INLINE void erts_runqs_lock(ErtsRunQueue *rq1, ErtsRunQueue *rq2);
+ERTS_GLB_INLINE void erts_runqs_unlock(ErtsRunQueue *rq1, ErtsRunQueue *rq2);
 
 ERTS_GLB_INLINE ErtsMessage *erts_alloc_message_heap_state(Process *pp,
 							   erts_aint32_t *psp,
@@ -2291,11 +2200,7 @@ ErtsSchedulerData *erts_proc_sched_data(Process *c_p)
 {
     ErtsSchedulerData *esdp;
     ASSERT(c_p);
-#if !defined(ERTS_SMP)
-    esdp = erts_get_scheduler_data();
-#else
     esdp = c_p->scheduler_data;
-#  if defined(ERTS_DIRTY_SCHEDULERS)
     if (esdp) {
 	ASSERT(esdp == erts_get_scheduler_data());
 	ASSERT(!ERTS_SCHEDULER_IS_DIRTY(esdp));
@@ -2305,8 +2210,6 @@ ErtsSchedulerData *erts_proc_sched_data(Process *c_p)
 	ASSERT(esdp);
 	ASSERT(ERTS_SCHEDULER_IS_DIRTY(esdp));
     }
-#  endif
-#endif
     ASSERT(esdp);
     return esdp;
 }
@@ -2337,124 +2240,94 @@ Eterm erts_get_current_pid(void)
 ERTS_GLB_INLINE
 Uint erts_get_scheduler_id(void)
 {
-#ifdef ERTS_SMP
     ErtsSchedulerData *esdp = erts_get_scheduler_data();
-#ifdef ERTS_DIRTY_SCHEDULERS
     if (esdp && ERTS_SCHEDULER_IS_DIRTY(esdp))
 	return 0;
     else
-#endif
 	return esdp ? esdp->no : (Uint) 0;
-#else
-    return erts_get_scheduler_data() ? (Uint) 1 : (Uint) 0;
-#endif
 }
 
 ERTS_GLB_INLINE ErtsRunQueue *
 erts_get_runq_proc(Process *p)
 {
-#ifdef ERTS_SMP
     ASSERT(ERTS_AINT_NULL != erts_atomic_read_nob(&p->run_queue));
     return (ErtsRunQueue *) erts_atomic_read_nob(&p->run_queue);
-#else
-    return ERTS_RUNQ_IX(0);
-#endif
 }
 
 ERTS_GLB_INLINE ErtsRunQueue *
 erts_get_runq_current(ErtsSchedulerData *esdp)
 {
     ASSERT(!esdp || esdp == erts_get_scheduler_data());
-#ifdef ERTS_SMP
     if (!esdp)
 	esdp = erts_get_scheduler_data();
     return esdp->run_queue;
-#else
-    return ERTS_RUNQ_IX(0);
-#endif
 }
 
 ERTS_GLB_INLINE void
-erts_smp_runq_lock(ErtsRunQueue *rq)
+erts_runq_lock(ErtsRunQueue *rq)
 {
-#ifdef ERTS_SMP
-    erts_smp_mtx_lock(&rq->mtx);
-#endif
+    erts_mtx_lock(&rq->mtx);
 }
 
 ERTS_GLB_INLINE int
-erts_smp_runq_trylock(ErtsRunQueue *rq)
+erts_runq_trylock(ErtsRunQueue *rq)
 {
-#ifdef ERTS_SMP
-    return erts_smp_mtx_trylock(&rq->mtx);
-#else
-    return 0;
-#endif
+    return erts_mtx_trylock(&rq->mtx);
 }
 
 ERTS_GLB_INLINE void
-erts_smp_runq_unlock(ErtsRunQueue *rq)
+erts_runq_unlock(ErtsRunQueue *rq)
 {
-#ifdef ERTS_SMP
-    erts_smp_mtx_unlock(&rq->mtx);
-#endif
+    erts_mtx_unlock(&rq->mtx);
 }
 
 ERTS_GLB_INLINE void
-erts_smp_xrunq_lock(ErtsRunQueue *rq, ErtsRunQueue *xrq)
+erts_xrunq_lock(ErtsRunQueue *rq, ErtsRunQueue *xrq)
 {
-#ifdef ERTS_SMP
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_mtx_is_locked(&rq->mtx));
+    ERTS_LC_ASSERT(erts_lc_mtx_is_locked(&rq->mtx));
     if (xrq != rq) {
-	if (erts_smp_mtx_trylock(&xrq->mtx) == EBUSY) {
+	if (erts_mtx_trylock(&xrq->mtx) == EBUSY) {
 	    if (rq < xrq)
-		erts_smp_mtx_lock(&xrq->mtx);
+		erts_mtx_lock(&xrq->mtx);
 	    else {
-		erts_smp_mtx_unlock(&rq->mtx);
-		erts_smp_mtx_lock(&xrq->mtx);
-		erts_smp_mtx_lock(&rq->mtx);
+		erts_mtx_unlock(&rq->mtx);
+		erts_mtx_lock(&xrq->mtx);
+		erts_mtx_lock(&rq->mtx);
 	    }
 	}
     }
-#endif
 }
 
 ERTS_GLB_INLINE void
-erts_smp_xrunq_unlock(ErtsRunQueue *rq, ErtsRunQueue *xrq)
+erts_xrunq_unlock(ErtsRunQueue *rq, ErtsRunQueue *xrq)
 {
-#ifdef ERTS_SMP
     if (xrq != rq)
-	erts_smp_mtx_unlock(&xrq->mtx);
-#endif
+	erts_mtx_unlock(&xrq->mtx);
 }
 
 ERTS_GLB_INLINE void
-erts_smp_runqs_lock(ErtsRunQueue *rq1, ErtsRunQueue *rq2)
+erts_runqs_lock(ErtsRunQueue *rq1, ErtsRunQueue *rq2)
 {
-#ifdef ERTS_SMP
     ASSERT(rq1 && rq2);
     if (rq1 == rq2)
-	erts_smp_mtx_lock(&rq1->mtx);
+	erts_mtx_lock(&rq1->mtx);
     else if (rq1 < rq2) {
-	erts_smp_mtx_lock(&rq1->mtx);
-	erts_smp_mtx_lock(&rq2->mtx);	
+	erts_mtx_lock(&rq1->mtx);
+	erts_mtx_lock(&rq2->mtx);
     }
     else {
-	erts_smp_mtx_lock(&rq2->mtx);
-	erts_smp_mtx_lock(&rq1->mtx);	
+	erts_mtx_lock(&rq2->mtx);
+	erts_mtx_lock(&rq1->mtx);
     }
-#endif
 }
 
 ERTS_GLB_INLINE void
-erts_smp_runqs_unlock(ErtsRunQueue *rq1, ErtsRunQueue *rq2)
+erts_runqs_unlock(ErtsRunQueue *rq1, ErtsRunQueue *rq2)
 {
-#ifdef ERTS_SMP
     ASSERT(rq1 && rq2);
-    erts_smp_mtx_unlock(&rq1->mtx);
+    erts_mtx_unlock(&rq1->mtx);
     if (rq1 != rq2)
-	erts_smp_mtx_unlock(&rq2->mtx);
-#endif
+	erts_mtx_unlock(&rq2->mtx);
 }
 
 ERTS_GLB_INLINE ErtsMessage *
@@ -2486,7 +2359,7 @@ erts_alloc_message_heap(Process *pp,
 			Eterm **hpp,
 			ErlOffHeap **ohpp)
 {
-    erts_aint32_t state = pp ? erts_smp_atomic32_read_nob(&pp->state) : 0;
+    erts_aint32_t state = pp ? erts_atomic32_read_nob(&pp->state) : 0;
     return erts_alloc_message_heap_state(pp, &state, plp, sz, hpp, ohpp);
 }
 
@@ -2500,7 +2373,7 @@ erts_shrink_message_heap(ErtsMessage **msgpp, Process *pp,
 	*msgpp = erts_shrink_message(*msgpp, used_hp - start_hp,
 				     brefs, brefs_size);
     else if (!(*msgpp)->data.attached) {
-	ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN
+	ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN
 			   & erts_proc_lc_my_proc_locks(pp));
 	HRelease(pp, end_hp, used_hp);
     }
@@ -2562,7 +2435,6 @@ ERTS_TIME2REDS_IMPL__(ErtsMonotonicTime start, ErtsMonotonicTime end)
 }
 #endif
 
-#ifdef ERTS_SMP
 
 Process *erts_pid2proc_not_running(Process *,
 				   ErtsProcLocks,
@@ -2575,37 +2447,29 @@ Process *erts_pid2proc_nropt(Process *c_p,
 extern int erts_disable_proc_not_running_opt;
 
 #ifdef DEBUG
-#define ERTS_SMP_ASSERT_IS_NOT_EXITING(P) \
+#define ERTS_ASSERT_IS_NOT_EXITING(P) \
     do { ASSERT(!ERTS_PROC_IS_EXITING((P))); } while (0)
 #else
-#define ERTS_SMP_ASSERT_IS_NOT_EXITING(P)
+#define ERTS_ASSERT_IS_NOT_EXITING(P)
 #endif
 
-#else /* !ERTS_SMP */
-
-#define ERTS_SMP_ASSERT_IS_NOT_EXITING(P)
-
-#define erts_pid2proc_not_running erts_pid2proc
-#define erts_pid2proc_nropt erts_pid2proc
-
-#endif
 
 #define ERTS_PROC_IS_EXITING(P) \
-    (ERTS_PSFLG_EXITING & erts_smp_atomic32_read_acqb(&(P)->state))
+    (ERTS_PSFLG_EXITING & erts_atomic32_read_acqb(&(P)->state))
 
 
 /* Minimum NUMBER of processes for a small system to start */
 #define ERTS_MIN_PROCESSES		1024
-#if defined(ERTS_SMP) && ERTS_MIN_PROCESSES < ERTS_NO_OF_PIX_LOCKS
+#if ERTS_MIN_PROCESSES < ERTS_NO_OF_PIX_LOCKS
 #undef ERTS_MIN_PROCESSES
 #define ERTS_MIN_PROCESSES		ERTS_NO_OF_PIX_LOCKS
 #endif
 
-void erts_smp_notify_inc_runq(ErtsRunQueue *runq);
+void erts_notify_inc_runq(ErtsRunQueue *runq);
 
-#ifdef ERTS_SMP
 void erts_sched_finish_poke(ErtsSchedulerSleepInfo *, erts_aint32_t);
 ERTS_GLB_INLINE void erts_sched_poke(ErtsSchedulerSleepInfo *ssi);
+void erts_aux_thread_poke(void);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
@@ -2614,9 +2478,9 @@ erts_sched_poke(ErtsSchedulerSleepInfo *ssi)
 {
     erts_aint32_t flags;
     ERTS_THR_MEMORY_BARRIER;
-    flags = erts_smp_atomic32_read_nob(&ssi->flags);
+    flags = erts_atomic32_read_nob(&ssi->flags);
     if (flags & ERTS_SSI_FLG_SLEEPING) {
-	flags = erts_smp_atomic32_read_band_nob(&ssi->flags, ~ERTS_SSI_FLGS_SLEEP);
+	flags = erts_atomic32_read_band_nob(&ssi->flags, ~ERTS_SSI_FLGS_SLEEP);
 	erts_sched_finish_poke(ssi, flags);
     }
 }
@@ -2624,7 +2488,6 @@ erts_sched_poke(ErtsSchedulerSleepInfo *ssi)
 
 #endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
-#endif /* #ifdef ERTS_SMP */
 
 #include "erl_process_lock.h"
 
@@ -2634,5 +2497,5 @@ erts_sched_poke(ErtsSchedulerSleepInfo *ssi)
 
 
 void erts_halt(int code);
-extern erts_smp_atomic32_t erts_halt_progress;
+extern erts_atomic32_t erts_halt_progress;
 extern int erts_halt_code;
diff --git a/erts/emulator/beam/erl_process_dump.c b/erts/emulator/beam/erl_process_dump.c
index e0b795fbf3..f562fc961b 100644
--- a/erts/emulator/beam/erl_process_dump.c
+++ b/erts/emulator/beam/erl_process_dump.c
@@ -77,7 +77,7 @@ erts_deep_process_dump(fmtfn_t to, void *to_arg)
     for (i = 0; i < max; i++) {
 	Process *p = erts_pix2proc(i);
 	if (p && p->i != ENULL) {
-	    erts_aint32_t state = erts_smp_atomic32_read_acqb(&p->state);
+	    erts_aint32_t state = erts_atomic32_read_acqb(&p->state);
 	    if (!(state & (ERTS_PSFLG_EXITING|ERTS_PSFLG_GC)))
 		dump_process_info(to, to_arg, p);
        }
@@ -94,7 +94,7 @@ Uint erts_process_memory(Process *p, int incl_msg_inq) {
   size += sizeof(Process);
 
   if (incl_msg_inq)
-      ERTS_SMP_MSGQ_MV_INQ2PRIVQ(p);
+      ERTS_MSGQ_MV_INQ2PRIVQ(p);
 
   erts_doforall_links(ERTS_P_LINKS(p), &erts_one_link_size, &size);
   erts_doforall_monitors(ERTS_P_MONITORS(p), &erts_one_mon_size, &size);
@@ -115,7 +115,7 @@ Uint erts_process_memory(Process *p, int incl_msg_inq) {
     size += p->arity * sizeof(p->arg_reg[0]);
   }
 
-  if (erts_smp_atomic_read_nob(&p->psd) != (erts_aint_t) NULL)
+  if (erts_atomic_read_nob(&p->psd) != (erts_aint_t) NULL)
     size += sizeof(ErtsPSD);
 
   scb = ERTS_PROC_GET_SAVED_CALLS_BUF(p);
@@ -135,7 +135,7 @@ dump_process_info(fmtfn_t to, void *to_arg, Process *p)
     ErtsMessage* mp;
     int yreg = -1;
 
-    ERTS_SMP_MSGQ_MV_INQ2PRIVQ(p);
+    ERTS_MSGQ_MV_INQ2PRIVQ(p);
 
     if ((ERTS_TRACE_FLAGS(p) & F_SENSITIVE) == 0 && p->msg.first) {
 	erts_print(to, to_arg, "=proc_messages:%T\n", p->common.id);
diff --git a/erts/emulator/beam/erl_process_lock.c b/erts/emulator/beam/erl_process_lock.c
index ff124d5ba7..431867f27e 100644
--- a/erts/emulator/beam/erl_process_lock.c
+++ b/erts/emulator/beam/erl_process_lock.c
@@ -56,9 +56,9 @@
  *     Note that wait flags may be read without the pix lock, but
  *   it is important that wait flags only are modified when the pix
  *   lock is held.
- *     This implementation assumes that erts_smp_atomic_or_retold()
+ *     This implementation assumes that erts_atomic_or_retold()
  *   provides necessary memorybarriers for a lock operation, and that
- *   erts_smp_atomic_and_retold() provides necessary memorybarriers
+ *   erts_atomic_and_retold() provides necessary memorybarriers
  *   for an unlock operation.
  */
 
@@ -69,7 +69,6 @@
 #include "erl_process.h"
 #include "erl_thr_progress.h"
 
-#ifdef ERTS_SMP
 
 #if ERTS_PROC_LOCK_OWN_IMPL
 
@@ -464,7 +463,7 @@ wait_for_locks(Process *p,
 }
 
 /*
- * erts_proc_lock_failed() is called when erts_smp_proc_lock()
+ * erts_proc_lock_failed() is called when erts_proc_lock()
  * wasn't able to lock all locks. We may need to transfer locks
  * to waiters and wait for our turn on locks.
  *
@@ -543,7 +542,7 @@ erts_proc_lock_failed(Process *p,
 }
 
 /*
- * erts_proc_unlock_failed() is called when erts_smp_proc_unlock()
+ * erts_proc_unlock_failed() is called when erts_proc_unlock()
  * wasn't able to unlock all locks. We may need to transfer locks
  * to waiters.
  */
@@ -709,7 +708,7 @@ proc_safelock(int is_managed,
 		refc1 = 1;
 		erts_proc_inc_refc(p1);
 	    }
-	    erts_smp_proc_unlock(p1, unlock_locks);
+	    erts_proc_unlock(p1, unlock_locks);
 	}
 	unlock_locks = unlock_mask & have_locks2;
 	if (unlock_locks) {
@@ -719,7 +718,7 @@ proc_safelock(int is_managed,
 		refc2 = 1;
 		erts_proc_inc_refc(p2);
 	    }
-	    erts_smp_proc_unlock(p2, unlock_locks);
+	    erts_proc_unlock(p2, unlock_locks);
 	}
     }
 
@@ -750,7 +749,7 @@ proc_safelock(int is_managed,
 	    if (need_locks2 & lock)
 		lock_no--;
 	    locks = need_locks1 & lock_mask;
-	    erts_smp_proc_lock(p1, locks);
+	    erts_proc_lock(p1, locks);
 	    have_locks1 |= locks;
 	    need_locks1 &= ~locks;
 	}
@@ -761,7 +760,7 @@ proc_safelock(int is_managed,
 		lock = (1 << ++lock_no);
 	    }
 	    locks = need_locks2 & lock_mask;
-	    erts_smp_proc_lock(p2, locks);
+	    erts_proc_lock(p2, locks);
 	    have_locks2 |= locks;
 	    need_locks2 &= ~locks;
 	}
@@ -898,7 +897,7 @@ erts_pid2proc_opt(Process *c_p,
 #endif /* ERTS_PROC_LOCK_OWN_IMPL */
 	    {
 		/* Try a quick trylock to grab all the locks we need. */
-		busy = (int) erts_smp_proc_raw_trylock__(proc, need_locks);
+		busy = (int) erts_proc_raw_trylock__(proc, need_locks);
 
 #if ERTS_PROC_LOCK_OWN_IMPL && defined(ERTS_ENABLE_LOCK_CHECK)
 		erts_proc_lc_trylock(proc, need_locks, !busy, __FILE__,__LINE__);
@@ -976,7 +975,7 @@ erts_pid2proc_opt(Process *c_p,
 	    : (proc
 	       != (Process *) erts_ptab_pix2intptr_nob(&erts_proc, pix)))) {
 
-	erts_smp_proc_unlock(proc, need_locks);
+	erts_proc_unlock(proc, need_locks);
 
 	if (flags & ERTS_P2P_FLG_INC_REFC)
 	    dec_refc_proc = proc;
@@ -1002,11 +1001,9 @@ static ERTS_INLINE
 Process *proc_lookup_inc_refc(Eterm pid, int allow_exit)
 {
     Process *proc;
-#ifdef ERTS_SMP
     ErtsThrPrgrDelayHandle dhndl;
 
     dhndl = erts_thr_progress_unmanaged_delay();
-#endif
 
     proc = erts_proc_lookup_raw(pid);
     if (proc) {
@@ -1016,9 +1013,7 @@ Process *proc_lookup_inc_refc(Eterm pid, int allow_exit)
             erts_proc_inc_refc(proc);
     }
 
-#ifdef ERTS_SMP
     erts_thr_progress_unmanaged_continue(dhndl);
-#endif
 
     return proc;
 }
@@ -1042,7 +1037,7 @@ erts_proc_lock_init(Process *p)
 #if ERTS_PROC_LOCK_OWN_IMPL
     /* We always start with all locks locked */
 #if ERTS_PROC_LOCK_ATOMIC_IMPL
-    erts_smp_atomic32_init_nob(&p->lock.flags,
+    erts_atomic32_init_nob(&p->lock.flags,
 			       (erts_aint32_t) ERTS_PROC_LOCKS_ALL);
 #else
     p->lock.flags = ERTS_PROC_LOCKS_ALL;
@@ -1093,7 +1088,7 @@ erts_proc_lock_init(Process *p)
 #endif
 #ifdef ERTS_PROC_LOCK_DEBUG
     for (i = 0; i <= ERTS_PROC_LOCK_MAX_BIT; i++)
-	erts_smp_atomic32_init_nob(&p->lock.locked[i], (erts_aint32_t) 1);
+	erts_atomic32_init_nob(&p->lock.locked[i], (erts_aint32_t) 1);
 #endif
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_proc_lock_init(p);
@@ -1113,7 +1108,7 @@ erts_proc_lock_fin(Process *p)
     erts_mtx_destroy(&p->lock.status);
     erts_mtx_destroy(&p->lock.trace);
 #endif
-#if defined(ERTS_ENABLE_LOCK_COUNT) && defined(ERTS_SMP)
+#if defined(ERTS_ENABLE_LOCK_COUNT)
     erts_lcnt_proc_lock_destroy(p);
 #endif
 }
@@ -1785,4 +1780,3 @@ check_queue(erts_proc_lock_t *lck)
 }
 #endif
 
-#endif /* ERTS_SMP */
diff --git a/erts/emulator/beam/erl_process_lock.h b/erts/emulator/beam/erl_process_lock.h
index 023ba4d4ae..9d5691d3c4 100644
--- a/erts/emulator/beam/erl_process_lock.h
+++ b/erts/emulator/beam/erl_process_lock.h
@@ -36,7 +36,7 @@
 #include "erl_lock_count.h"
 #endif
 
-#include "erl_smp.h"
+#include "erl_threads.h"
 
 #if defined(VALGRIND) || defined(ETHR_DISABLE_NATIVE_IMPLS)
 #  define ERTS_PROC_LOCK_OWN_IMPL 0
@@ -73,7 +73,7 @@ typedef erts_aint32_t ErtsProcLocks;
 typedef struct erts_proc_lock_t_ {
 #if ERTS_PROC_LOCK_OWN_IMPL
 #if ERTS_PROC_LOCK_ATOMIC_IMPL
-    erts_smp_atomic32_t flags;
+    erts_atomic32_t flags;
 #else
     ErtsProcLocks flags;
 #endif
@@ -103,7 +103,7 @@ typedef struct erts_proc_lock_t_ {
 #  error "no implementation"
 #endif
 #ifdef ERTS_PROC_LOCK_DEBUG
-    erts_smp_atomic32_t locked[ERTS_PROC_LOCK_MAX_BIT+1];
+    erts_atomic32_t locked[ERTS_PROC_LOCK_MAX_BIT+1];
 #endif
 } erts_proc_lock_t;
 
@@ -243,11 +243,11 @@ typedef struct erts_proc_lock_t_ {
 /* Lock counter implemetation */
 
 #ifdef ERTS_ENABLE_LOCK_POSITION
-#define erts_smp_proc_lock__(P,I,L) erts_smp_proc_lock_x__(P,I,L,__FILE__,__LINE__)
-#define erts_smp_proc_lock(P,L) erts_smp_proc_lock_x(P,L,__FILE__,__LINE__)
+#define erts_proc_lock__(P,I,L) erts_proc_lock_x__(P,I,L,__FILE__,__LINE__)
+#define erts_proc_lock(P,L) erts_proc_lock_x(P,L,__FILE__,__LINE__)
 #endif
 
-#if defined(ERTS_SMP) && defined (ERTS_ENABLE_LOCK_COUNT)
+#if defined (ERTS_ENABLE_LOCK_COUNT)
 
 void erts_lcnt_proc_lock_init(Process *p);
 void erts_lcnt_proc_lock_destroy(Process *p);
@@ -421,10 +421,10 @@ void erts_lcnt_proc_trylock(erts_proc_lock_t *lock, ErtsProcLocks locks, int res
 
 /* --- Process lock checking ----------------------------------------------- */
 
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
-#define ERTS_SMP_CHK_NO_PROC_LOCKS \
+#if defined(ERTS_ENABLE_LOCK_CHECK)
+#define ERTS_CHK_NO_PROC_LOCKS \
   erts_proc_lc_chk_no_proc_locks(__FILE__, __LINE__)
-#define ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(P) \
+#define ERTS_CHK_HAVE_ONLY_MAIN_PROC_LOCK(P) \
   erts_proc_lc_chk_only_proc_main((P))
 void erts_proc_lc_lock(Process *p, ErtsProcLocks locks,
 		       char *file, unsigned int line);
@@ -443,8 +443,8 @@ void erts_proc_lc_require_lock(Process *p, ErtsProcLocks locks,
 			       char* file, unsigned int line);
 void erts_proc_lc_unrequire_lock(Process *p, ErtsProcLocks locks);
 #else
-#define ERTS_SMP_CHK_NO_PROC_LOCKS
-#define ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(P)
+#define ERTS_CHK_NO_PROC_LOCKS
+#define ERTS_CHK_HAVE_ONLY_MAIN_PROC_LOCK(P)
 #endif
 
 #endif /* #ifndef ERTS_PROC_LOCK_LOCK_CHECK__ */
@@ -455,7 +455,6 @@ void erts_proc_lc_unrequire_lock(Process *p, ErtsProcLocks locks);
 #ifndef ERTS_PROCESS_LOCK_H__
 #define ERTS_PROCESS_LOCK_H__
 
-#ifdef ERTS_SMP
 
 typedef struct {
     union {
@@ -472,21 +471,21 @@ typedef struct {
 #if ERTS_PROC_LOCK_ATOMIC_IMPL
 
 #define ERTS_PROC_LOCK_FLGS_BAND_(L, MSK) \
-  ((ErtsProcLocks) erts_smp_atomic32_read_band_nob(&(L)->flags, \
+  ((ErtsProcLocks) erts_atomic32_read_band_nob(&(L)->flags, \
 						   (erts_aint32_t) (MSK)))
 #define ERTS_PROC_LOCK_FLGS_BOR_ACQB_(L, MSK) \
-  ((ErtsProcLocks) erts_smp_atomic32_read_bor_acqb(&(L)->flags, \
+  ((ErtsProcLocks) erts_atomic32_read_bor_acqb(&(L)->flags, \
 						   (erts_aint32_t) (MSK)))
 #define ERTS_PROC_LOCK_FLGS_CMPXCHG_ACQB_(L, NEW, EXPECTED) \
-  ((ErtsProcLocks) erts_smp_atomic32_cmpxchg_acqb(&(L)->flags, \
+  ((ErtsProcLocks) erts_atomic32_cmpxchg_acqb(&(L)->flags, \
 						  (erts_aint32_t) (NEW), \
 						  (erts_aint32_t) (EXPECTED)))
 #define ERTS_PROC_LOCK_FLGS_CMPXCHG_RELB_(L, NEW, EXPECTED) \
-  ((ErtsProcLocks) erts_smp_atomic32_cmpxchg_relb(&(L)->flags, \
+  ((ErtsProcLocks) erts_atomic32_cmpxchg_relb(&(L)->flags, \
 						  (erts_aint32_t) (NEW), \
 						  (erts_aint32_t) (EXPECTED)))
 #define ERTS_PROC_LOCK_FLGS_READ_(L) \
-  ((ErtsProcLocks) erts_smp_atomic32_read_nob(&(L)->flags))
+  ((ErtsProcLocks) erts_atomic32_read_nob(&(L)->flags))
 
 #else /* no opt atomic ops */
 
@@ -557,22 +556,22 @@ ERTS_GLB_INLINE void erts_pix_lock(erts_pix_lock_t *);
 ERTS_GLB_INLINE void erts_pix_unlock(erts_pix_lock_t *);
 ERTS_GLB_INLINE int erts_lc_pix_lock_is_locked(erts_pix_lock_t *);
 
-ERTS_GLB_INLINE ErtsProcLocks erts_smp_proc_raw_trylock__(Process *p,
+ERTS_GLB_INLINE ErtsProcLocks erts_proc_raw_trylock__(Process *p,
 							  ErtsProcLocks locks);
 #ifdef ERTS_ENABLE_LOCK_POSITION
-ERTS_GLB_INLINE void erts_smp_proc_lock_x__(Process *,
+ERTS_GLB_INLINE void erts_proc_lock_x__(Process *,
 					    erts_pix_lock_t *,
 					    ErtsProcLocks,
 					    char *file, unsigned int line);
 #else
-ERTS_GLB_INLINE void erts_smp_proc_lock__(Process *,
+ERTS_GLB_INLINE void erts_proc_lock__(Process *,
 					  erts_pix_lock_t *,
 					  ErtsProcLocks);
 #endif
-ERTS_GLB_INLINE void erts_smp_proc_unlock__(Process *,
+ERTS_GLB_INLINE void erts_proc_unlock__(Process *,
 					    erts_pix_lock_t *,
 					    ErtsProcLocks);
-ERTS_GLB_INLINE int erts_smp_proc_trylock__(Process *,
+ERTS_GLB_INLINE int erts_proc_trylock__(Process *,
 					    erts_pix_lock_t *,
 					    ErtsProcLocks);
 
@@ -600,7 +599,7 @@ ERTS_GLB_INLINE int erts_lc_pix_lock_is_locked(erts_pix_lock_t *pixlck)
 }
 
 /*
- * Helper function for erts_smp_proc_lock__ and erts_smp_proc_trylock__.
+ * Helper function for erts_proc_lock__ and erts_proc_trylock__.
  *
  * Attempts to grab all of 'locks' simultaneously.
  *
@@ -613,7 +612,7 @@ ERTS_GLB_INLINE int erts_lc_pix_lock_is_locked(erts_pix_lock_t *pixlck)
  * Does not release the pix lock.
  */
 ERTS_GLB_INLINE ErtsProcLocks
-erts_smp_proc_raw_trylock__(Process *p, ErtsProcLocks locks)
+erts_proc_raw_trylock__(Process *p, ErtsProcLocks locks)
 {
 #if ERTS_PROC_LOCK_OWN_IMPL
     ErtsProcLocks expct_lflgs = 0;
@@ -682,12 +681,12 @@ busy_main:
 
 ERTS_GLB_INLINE void
 #ifdef ERTS_ENABLE_LOCK_POSITION
-erts_smp_proc_lock_x__(Process *p,
+erts_proc_lock_x__(Process *p,
 		     erts_pix_lock_t *pix_lck,
 		     ErtsProcLocks locks,
 		     char *file, unsigned int line)
 #else
-erts_smp_proc_lock__(Process *p,
+erts_proc_lock__(Process *p,
 		     erts_pix_lock_t *pix_lck,
 		     ErtsProcLocks locks)
 #endif
@@ -709,7 +708,7 @@ erts_smp_proc_lock__(Process *p,
     erts_proc_lc_lock(p, locks, file, line);
 #endif
 
-    old_lflgs = erts_smp_proc_raw_trylock__(p, locks);
+    old_lflgs = erts_proc_raw_trylock__(p, locks);
 
     if (old_lflgs != 0) {
 	/*
@@ -761,7 +760,7 @@ erts_smp_proc_lock__(Process *p,
 }
 
 ERTS_GLB_INLINE void
-erts_smp_proc_unlock__(Process *p,
+erts_proc_unlock__(Process *p,
 		       erts_pix_lock_t *pix_lck,
 		       ErtsProcLocks locks)
 {
@@ -854,7 +853,7 @@ erts_smp_proc_unlock__(Process *p,
 }
 
 ERTS_GLB_INLINE int
-erts_smp_proc_trylock__(Process *p,
+erts_proc_trylock__(Process *p,
 			erts_pix_lock_t *pix_lck,
 			ErtsProcLocks locks)
 {
@@ -875,7 +874,7 @@ erts_smp_proc_trylock__(Process *p,
 	erts_pix_lock(pix_lck);
 #endif
 
-	if (erts_smp_proc_raw_trylock__(p, locks) != 0) {
+	if (erts_proc_raw_trylock__(p, locks) != 0) {
 	    /* Didn't get all locks... */
 	    res = EBUSY;
 
@@ -912,7 +911,7 @@ erts_smp_proc_trylock__(Process *p,
     return res;
 
 #elif ERTS_PROC_LOCK_RAW_MUTEX_IMPL
-    if (erts_smp_proc_raw_trylock__(p, locks) != 0)
+    if (erts_proc_raw_trylock__(p, locks) != 0)
 	return EBUSY;
     else {
 #ifdef ERTS_PROC_LOCK_DEBUG
@@ -933,11 +932,11 @@ erts_proc_lock_op_debug(Process *p, ErtsProcLocks locks, int locked)
 	if (locks & lock) {
 	    erts_aint32_t lock_count;
 	    if (locked) {
-		lock_count = erts_smp_atomic32_inc_read_nob(&p->lock.locked[i]);
+		lock_count = erts_atomic32_inc_read_nob(&p->lock.locked[i]);
 		ERTS_LC_ASSERT(lock_count == 1);
 	    }
 	    else {
-		lock_count = erts_smp_atomic32_dec_read_nob(&p->lock.locked[i]);
+		lock_count = erts_atomic32_dec_read_nob(&p->lock.locked[i]);
 		ERTS_LC_ASSERT(lock_count == 0);
 	    }
 	}
@@ -947,15 +946,14 @@ erts_proc_lock_op_debug(Process *p, ErtsProcLocks locks, int locked)
 
 #endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
-#endif /* ERTS_SMP */
 
 #ifdef ERTS_ENABLE_LOCK_POSITION
-ERTS_GLB_INLINE void erts_smp_proc_lock_x(Process *, ErtsProcLocks, char *file, unsigned int line);
+ERTS_GLB_INLINE void erts_proc_lock_x(Process *, ErtsProcLocks, char *file, unsigned int line);
 #else
-ERTS_GLB_INLINE void erts_smp_proc_lock(Process *, ErtsProcLocks);
+ERTS_GLB_INLINE void erts_proc_lock(Process *, ErtsProcLocks);
 #endif
-ERTS_GLB_INLINE void erts_smp_proc_unlock(Process *, ErtsProcLocks);
-ERTS_GLB_INLINE int erts_smp_proc_trylock(Process *, ErtsProcLocks);
+ERTS_GLB_INLINE void erts_proc_unlock(Process *, ErtsProcLocks);
+ERTS_GLB_INLINE int erts_proc_trylock(Process *, ErtsProcLocks);
 
 ERTS_GLB_INLINE void erts_proc_inc_refc(Process *);
 ERTS_GLB_INLINE void erts_proc_dec_refc(Process *);
@@ -966,79 +964,65 @@ ERTS_GLB_INLINE Sint erts_proc_read_refc(Process *);
 
 ERTS_GLB_INLINE void
 #ifdef ERTS_ENABLE_LOCK_POSITION
-erts_smp_proc_lock_x(Process *p, ErtsProcLocks locks, char *file, unsigned int line)
+erts_proc_lock_x(Process *p, ErtsProcLocks locks, char *file, unsigned int line)
 #else
-erts_smp_proc_lock(Process *p, ErtsProcLocks locks)
+erts_proc_lock(Process *p, ErtsProcLocks locks)
 #endif 
 {
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_POSITION)
-    erts_smp_proc_lock_x__(p,
+#if defined(ERTS_ENABLE_LOCK_POSITION)
+    erts_proc_lock_x__(p,
 #if ERTS_PROC_LOCK_ATOMIC_IMPL
 			 NULL,
 #else
 			 ERTS_PID2PIXLOCK(p->common.id),
 #endif /*ERTS_PROC_LOCK_ATOMIC_IMPL*/
 			 locks, file, line);
-#elif defined(ERTS_SMP)
-    erts_smp_proc_lock__(p,
+#else
+    erts_proc_lock__(p,
 #if ERTS_PROC_LOCK_ATOMIC_IMPL
 			 NULL,
 #else
 			 ERTS_PID2PIXLOCK(p->common.id),
 #endif /*ERTS_PROC_LOCK_ATOMIC_IMPL*/
 			 locks);
-#endif /*ERTS_SMP*/
+#endif /*ERTS_ENABLE_LOCK_POSITION*/
 }
 
 ERTS_GLB_INLINE void
-erts_smp_proc_unlock(Process *p, ErtsProcLocks locks)
+erts_proc_unlock(Process *p, ErtsProcLocks locks)
 {
-#ifdef ERTS_SMP
-    erts_smp_proc_unlock__(p,
+    erts_proc_unlock__(p,
 #if ERTS_PROC_LOCK_ATOMIC_IMPL
 			   NULL,
 #else
 			   ERTS_PID2PIXLOCK(p->common.id),
 #endif
 			   locks);
-#endif
 }
 
 ERTS_GLB_INLINE int
-erts_smp_proc_trylock(Process *p, ErtsProcLocks locks)
+erts_proc_trylock(Process *p, ErtsProcLocks locks)
 {
-#ifndef ERTS_SMP
-    return 0;
-#else
-    return erts_smp_proc_trylock__(p,
+    return erts_proc_trylock__(p,
 #if ERTS_PROC_LOCK_ATOMIC_IMPL
 				   NULL,
 #else
 				   ERTS_PID2PIXLOCK(p->common.id),
 #endif
 				   locks);
-#endif
 }
 
 ERTS_GLB_INLINE void erts_proc_inc_refc(Process *p)
 {
-    ASSERT(!(erts_smp_atomic32_read_nob(&p->state) & ERTS_PSFLG_PROXY));
-#ifdef ERTS_SMP
+    ASSERT(!(erts_atomic32_read_nob(&p->state) & ERTS_PSFLG_PROXY));
     erts_ptab_atmc_inc_refc(&p->common);
-#else
-    erts_ptab_inc_refc(&p->common);
-#endif
 }
 
 ERTS_GLB_INLINE void erts_proc_dec_refc(Process *p)
 {
     Sint referred;
-    ASSERT(!(erts_smp_atomic32_read_nob(&p->state) & ERTS_PSFLG_PROXY));
-#ifdef ERTS_SMP
+    ASSERT(!(erts_atomic32_read_nob(&p->state) & ERTS_PSFLG_PROXY));
     referred = erts_ptab_atmc_dec_test_refc(&p->common);
-#else
-    referred = erts_ptab_dec_test_refc(&p->common);
-#endif
     if (!referred) {
 	ASSERT(ERTS_PROC_IS_EXITING(p));
 	erts_free_proc(p);
@@ -1048,12 +1032,8 @@ ERTS_GLB_INLINE void erts_proc_dec_refc(Process *p)
 ERTS_GLB_INLINE void erts_proc_add_refc(Process *p, Sint add_refc)
 {
     Sint referred;
-    ASSERT(!(erts_smp_atomic32_read_nob(&p->state) & ERTS_PSFLG_PROXY));
-#ifdef ERTS_SMP
+    ASSERT(!(erts_atomic32_read_nob(&p->state) & ERTS_PSFLG_PROXY));
     referred = erts_ptab_atmc_add_test_refc(&p->common, add_refc);
-#else
-    referred = erts_ptab_add_test_refc(&p->common, add_refc);
-#endif
     if (!referred) {
 	ASSERT(ERTS_PROC_IS_EXITING(p));
 	erts_free_proc(p);
@@ -1062,17 +1042,12 @@ ERTS_GLB_INLINE void erts_proc_add_refc(Process *p, Sint add_refc)
 
 ERTS_GLB_INLINE Sint erts_proc_read_refc(Process *p)
 {
-    ASSERT(!(erts_smp_atomic32_read_nob(&p->state) & ERTS_PSFLG_PROXY));
-#ifdef ERTS_SMP
+    ASSERT(!(erts_atomic32_read_nob(&p->state) & ERTS_PSFLG_PROXY));
     return erts_ptab_atmc_read_refc(&p->common);
-#else
-    return erts_ptab_read_refc(&p->common);
-#endif
 }
 
 #endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
-#ifdef ERTS_SMP
 void erts_proc_lock_init(Process *);
 void erts_proc_lock_fin(Process *);
 void erts_proc_safelock(Process *a_proc,
@@ -1081,7 +1056,6 @@ void erts_proc_safelock(Process *a_proc,
 			Process *b_proc,
 			ErtsProcLocks b_have_locks,
 			ErtsProcLocks b_need_locks);
-#endif
 
 /*
  * --- Process table lookup ------------------------------------------------
@@ -1113,9 +1087,6 @@ ERTS_GLB_INLINE Process *erts_pix2proc(int ix);
 ERTS_GLB_INLINE Process *erts_proc_lookup_raw(Eterm pid);
 ERTS_GLB_INLINE Process *erts_proc_lookup(Eterm pid);
 
-#ifndef ERTS_SMP
-ERTS_GLB_INLINE
-#endif
 Process *erts_pid2proc_opt(Process *, ErtsProcLocks, Eterm, ErtsProcLocks, int);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
@@ -1132,7 +1103,7 @@ ERTS_GLB_INLINE Process *erts_proc_lookup_raw(Eterm pid)
 {
     Process *proc;
 
-    ERTS_SMP_LC_ASSERT(erts_thr_progress_lc_is_delaying());
+    ERTS_LC_ASSERT(erts_thr_progress_lc_is_delaying());
 
     if (is_not_internal_pid(pid))
 	return NULL;
@@ -1152,25 +1123,6 @@ ERTS_GLB_INLINE Process *erts_proc_lookup(Eterm pid)
     return proc;
 }
 
-#ifndef ERTS_SMP
-ERTS_GLB_INLINE Process *
-erts_pid2proc_opt(Process *c_p_unused,
-		  ErtsProcLocks c_p_have_locks_unused,
-		  Eterm pid,
-		  ErtsProcLocks pid_need_locks_unused,
-		  int flags)
-{
-    Process *proc = erts_proc_lookup_raw(pid);
-    if (!proc)
-	return NULL;
-    if (!(flags & ERTS_P2P_FLG_ALLOW_OTHER_X)
-	&& ERTS_PROC_IS_EXITING(proc))
-	return NULL;
-    if (flags & ERTS_P2P_FLG_INC_REFC)
-	erts_proc_inc_refc(proc);
-    return proc;
-}
-#endif /* !ERTS_SMP */
 
 #endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
diff --git a/erts/emulator/beam/erl_ptab.c b/erts/emulator/beam/erl_ptab.c
index b3bcb3af3f..38c095fb4a 100644
--- a/erts/emulator/beam/erl_ptab.c
+++ b/erts/emulator/beam/erl_ptab.c
@@ -284,31 +284,31 @@ struct ErtsPTabListBifData_ {
 static ERTS_INLINE void
 last_data_init_nob(ErtsPTab *ptab, Uint64 val)
 {
-    erts_smp_atomic64_init_nob(&ptab->vola.tile.last_data, (erts_aint64_t) val);
+    erts_atomic64_init_nob(&ptab->vola.tile.last_data, (erts_aint64_t) val);
 }
 
 static ERTS_INLINE void
 last_data_set_relb(ErtsPTab *ptab, Uint64 val)
 {
-    erts_smp_atomic64_set_relb(&ptab->vola.tile.last_data, (erts_aint64_t) val);
+    erts_atomic64_set_relb(&ptab->vola.tile.last_data, (erts_aint64_t) val);
 }
 
 static ERTS_INLINE Uint64
 last_data_read_nob(ErtsPTab *ptab)
 {
-    return (Uint64) erts_smp_atomic64_read_nob(&ptab->vola.tile.last_data);
+    return (Uint64) erts_atomic64_read_nob(&ptab->vola.tile.last_data);
 }
 
 static ERTS_INLINE Uint64
 last_data_read_acqb(ErtsPTab *ptab)
 {
-    return (Uint64) erts_smp_atomic64_read_acqb(&ptab->vola.tile.last_data);
+    return (Uint64) erts_atomic64_read_acqb(&ptab->vola.tile.last_data);
 }
 
 static ERTS_INLINE Uint64
 last_data_cmpxchg_relb(ErtsPTab *ptab, Uint64 new, Uint64 exp)
 {
-    return (Uint64) erts_smp_atomic64_cmpxchg_relb(&ptab->vola.tile.last_data,
+    return (Uint64) erts_atomic64_cmpxchg_relb(&ptab->vola.tile.last_data,
 						   (erts_aint64_t) new,
 						   (erts_aint64_t) exp);
 }
@@ -346,9 +346,9 @@ ix_to_free_id_data_ix(ErtsPTab *ptab, Uint32 ix)
 UWord
 erts_ptab_mem_size(ErtsPTab *ptab)
 {
-    UWord size = ptab->r.o.max*sizeof(erts_smp_atomic_t);
+    UWord size = ptab->r.o.max*sizeof(erts_atomic_t);
     if (ptab->r.o.free_id_data)
-	size += ptab->r.o.max*sizeof(erts_smp_atomic32_t);
+	size += ptab->r.o.max*sizeof(erts_atomic32_t);
     return size;
 }
 
@@ -367,14 +367,14 @@ erts_ptab_init_table(ErtsPTab *ptab,
     size_t tab_sz, alloc_sz;
     Uint32 bits, cl, cli, ix, ix_per_cache_line, tab_cache_lines; 
     char *tab_end;
-    erts_smp_atomic_t *tab_entry;
-    erts_smp_rwmtx_opt_t rwmtx_opts = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
-    rwmtx_opts.type = ERTS_SMP_RWMTX_TYPE_EXTREMELY_FREQUENT_READ;
-    rwmtx_opts.lived = ERTS_SMP_RWMTX_LONG_LIVED;
+    erts_atomic_t *tab_entry;
+    erts_rwmtx_opt_t rwmtx_opts = ERTS_RWMTX_OPT_DEFAULT_INITER;
+    rwmtx_opts.type = ERTS_RWMTX_TYPE_EXTREMELY_FREQUENT_READ;
+    rwmtx_opts.lived = ERTS_RWMTX_LONG_LIVED;
 
-    erts_smp_rwmtx_init_opt(&ptab->list.data.rwmtx, &rwmtx_opts, name, NIL,
+    erts_rwmtx_init_opt(&ptab->list.data.rwmtx, &rwmtx_opts, name, NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
-    erts_smp_atomic32_init_nob(&ptab->vola.tile.count, 0);
+    erts_atomic32_init_nob(&ptab->vola.tile.count, 0);
     last_data_init_nob(ptab, ~((Uint64) 0));
 
     /* A size that is a power of 2 is to prefer performance wise */
@@ -388,20 +388,20 @@ erts_ptab_init_table(ErtsPTab *ptab,
     ptab->r.o.element_size = element_size;
     ptab->r.o.max = size;
 
-    tab_sz = ERTS_ALC_CACHE_LINE_ALIGN_SIZE(size*sizeof(erts_smp_atomic_t));
+    tab_sz = ERTS_ALC_CACHE_LINE_ALIGN_SIZE(size*sizeof(erts_atomic_t));
     alloc_sz = tab_sz;
     if (!legacy)
-	alloc_sz += ERTS_ALC_CACHE_LINE_ALIGN_SIZE(size*sizeof(erts_smp_atomic32_t));
+	alloc_sz += ERTS_ALC_CACHE_LINE_ALIGN_SIZE(size*sizeof(erts_atomic32_t));
     ptab->r.o.tab = erts_alloc_permanent_cache_aligned(atype, alloc_sz);
     tab_end = ((char *) ptab->r.o.tab) + tab_sz;
     tab_entry = ptab->r.o.tab;
     while (tab_end > ((char *) tab_entry)) {
-	erts_smp_atomic_init_nob(tab_entry, ERTS_AINT_NULL);
+	erts_atomic_init_nob(tab_entry, ERTS_AINT_NULL);
 	tab_entry++;
     }
 
     tab_cache_lines = tab_sz/ERTS_CACHE_LINE_SIZE;
-    ix_per_cache_line = (ERTS_CACHE_LINE_SIZE/sizeof(erts_smp_atomic_t));
+    ix_per_cache_line = (ERTS_CACHE_LINE_SIZE/sizeof(erts_atomic_t));
     ASSERT((ptab->r.o.max & (ptab->r.o.max - 1)) == 0); /* power of 2 */
     ASSERT((ix_per_cache_line & (ix_per_cache_line - 1)) == 0); /* power of 2 */
     ASSERT((tab_cache_lines & (tab_cache_lines - 1)) == 0); /* power of 2 */
@@ -429,11 +429,11 @@ erts_ptab_init_table(ErtsPTab *ptab,
     }
     else {
 
-	tab_sz = ERTS_ALC_CACHE_LINE_ALIGN_SIZE(size*sizeof(erts_smp_atomic32_t));
-	ptab->r.o.free_id_data = (erts_smp_atomic32_t *) tab_end;
+	tab_sz = ERTS_ALC_CACHE_LINE_ALIGN_SIZE(size*sizeof(erts_atomic32_t));
+	ptab->r.o.free_id_data = (erts_atomic32_t *) tab_end;
 
 	tab_cache_lines = tab_sz/ERTS_CACHE_LINE_SIZE;
-	ix_per_cache_line = (ERTS_CACHE_LINE_SIZE/sizeof(erts_smp_atomic32_t));
+	ix_per_cache_line = (ERTS_CACHE_LINE_SIZE/sizeof(erts_atomic32_t));
 
 	ptab->r.o.dix_cl_mask = tab_cache_lines-1;
 	ptab->r.o.dix_cl_shift = erts_fit_in_bits_int32(ix_per_cache_line-1);
@@ -448,19 +448,19 @@ erts_ptab_init_table(ErtsPTab *ptab,
 	ix = 0;
 	for (cl = 0; cl < tab_cache_lines; cl++) {
 	    for (cli = 0; cli < ix_per_cache_line; cli++) {
-		erts_smp_atomic32_init_nob(&ptab->r.o.free_id_data[ix],
+		erts_atomic32_init_nob(&ptab->r.o.free_id_data[ix],
 					   cli*tab_cache_lines+cl);
-		ASSERT(erts_smp_atomic32_read_nob(&ptab->r.o.free_id_data[ix]) != ptab->r.o.invalid_data);
+		ASSERT(erts_atomic32_read_nob(&ptab->r.o.free_id_data[ix]) != ptab->r.o.invalid_data);
 		ix++;
 	    }
 	}
 
-	erts_smp_atomic32_init_nob(&ptab->vola.tile.aid_ix, -1);
-	erts_smp_atomic32_init_nob(&ptab->vola.tile.fid_ix, -1);
+	erts_atomic32_init_nob(&ptab->vola.tile.aid_ix, -1);
+	erts_atomic32_init_nob(&ptab->vola.tile.fid_ix, -1);
 
     }
 
-    erts_smp_interval_init(&ptab->list.data.interval);
+    erts_interval_init(&ptab->list.data.interval);
     ptab->list.data.deleted.start = NULL;
     ptab->list.data.deleted.end = NULL;
     ptab->list.data.chunks = (((ptab->r.o.max - 1)
@@ -480,9 +480,9 @@ erts_ptab_init_table(ErtsPTab *ptab,
 	 * have ERTS_PTAB_MAX_SIZE-1 valid elements in the table while
 	 * still having a table size of the power of 2.
 	 */
-	erts_smp_atomic32_inc_nob(&ptab->vola.tile.count);
+	erts_atomic32_inc_nob(&ptab->vola.tile.count);
 	pix = erts_ptab_data2pix(ptab, ptab->r.o.invalid_data);
-	erts_smp_atomic_set_relb(&ptab->r.o.tab[pix],
+	erts_atomic_set_relb(&ptab->r.o.tab[pix],
 				 (erts_aint_t) ptab->r.o.invalid_element);
     }
 
@@ -506,12 +506,12 @@ erts_ptab_new_element(ErtsPTab *ptab,
 
     erts_ptab_rlock(ptab);
 
-    count = erts_smp_atomic32_inc_read_acqb(&ptab->vola.tile.count);
+    count = erts_atomic32_inc_read_acqb(&ptab->vola.tile.count);
     if (count > ptab->r.o.max) {
 	while (1) {
 	    erts_aint32_t act_count;
 
-	    act_count = erts_smp_atomic32_cmpxchg_relb(&ptab->vola.tile.count,
+	    act_count = erts_atomic32_cmpxchg_relb(&ptab->vola.tile.count,
 						       count-1,
 						       count);
 	    if (act_count == count) {
@@ -525,14 +525,14 @@ erts_ptab_new_element(ErtsPTab *ptab,
     }
 
     ptab_el->u.alive.started_interval
-	= erts_smp_current_interval_nob(erts_ptab_interval(ptab));
+	= erts_current_interval_nob(erts_ptab_interval(ptab));
 
     if (ptab->r.o.free_id_data) {
 	do {
-	    ix = (Uint32) erts_smp_atomic32_inc_read_acqb(&ptab->vola.tile.aid_ix);
+	    ix = (Uint32) erts_atomic32_inc_read_acqb(&ptab->vola.tile.aid_ix);
 	    ix = ix_to_free_id_data_ix(ptab, ix);
 
-	    data = erts_smp_atomic32_xchg_nob(&ptab->r.o.free_id_data[ix],
+	    data = erts_atomic32_xchg_nob(&ptab->r.o.free_id_data[ix],
 					      (erts_aint32_t)ptab->r.o.invalid_data);
 	}while ((Eterm)data == ptab->r.o.invalid_data);
 
@@ -546,10 +546,10 @@ erts_ptab_new_element(ErtsPTab *ptab,
 	pix = erts_ptab_data2pix(ptab, (Eterm) data);
 
 #ifdef DEBUG
-	ASSERT(ERTS_AINT_NULL == erts_smp_atomic_xchg_relb(&ptab->r.o.tab[pix],
+	ASSERT(ERTS_AINT_NULL == erts_atomic_xchg_relb(&ptab->r.o.tab[pix],
 							   (erts_aint_t) ptab_el));
 #else
-	erts_smp_atomic_set_relb(&ptab->r.o.tab[pix], (erts_aint_t) ptab_el);
+	erts_atomic_set_relb(&ptab->r.o.tab[pix], (erts_aint_t) ptab_el);
 #endif
 
 	erts_ptab_runlock(ptab);
@@ -563,7 +563,7 @@ erts_ptab_new_element(ErtsPTab *ptab,
     restart:
 
 	ptab_el->u.alive.started_interval
-	    = erts_smp_current_interval_nob(erts_ptab_interval(ptab));
+	    = erts_current_interval_nob(erts_ptab_interval(ptab));
 
 	ld = last_data_read_acqb(ptab);
 
@@ -571,10 +571,10 @@ erts_ptab_new_element(ErtsPTab *ptab,
 	while (1) {
 	    ld++;
 	    pix = erts_ptab_data2pix(ptab, ERTS_PTAB_LastData2EtermData(ld));
-	    if (erts_smp_atomic_read_nob(&ptab->r.o.tab[pix])
+	    if (erts_atomic_read_nob(&ptab->r.o.tab[pix])
 		== ERTS_AINT_NULL) {
 		erts_aint_t val;
-		val = erts_smp_atomic_cmpxchg_relb(&ptab->r.o.tab[pix],
+		val = erts_atomic_cmpxchg_relb(&ptab->r.o.tab[pix],
 						   invalid,	
 						   ERTS_AINT_NULL);
 
@@ -621,10 +621,10 @@ erts_ptab_new_element(ErtsPTab *ptab,
 
 	/* Move into slot reserved */
 #ifdef DEBUG
-	ASSERT(invalid == erts_smp_atomic_xchg_relb(&ptab->r.o.tab[pix],
+	ASSERT(invalid == erts_atomic_xchg_relb(&ptab->r.o.tab[pix],
 						(erts_aint_t) ptab_el));
 #else
-	erts_smp_atomic_set_relb(&ptab->r.o.tab[pix], (erts_aint_t) ptab_el);
+	erts_atomic_set_relb(&ptab->r.o.tab[pix], (erts_aint_t) ptab_el);
 #endif
 
 	if (rlocked)
@@ -644,7 +644,7 @@ save_deleted_element(ErtsPTab *ptab, ErtsPTabElementCommon *ptab_el)
 					       sizeof(ErtsPTabDeletedElement));
     ERTS_PTAB_LIST_ASSERT(ptab->list.data.deleted.start
 			  && ptab->list.data.deleted.end);
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_ptab_is_rwlocked(ptab));
+    ERTS_LC_ASSERT(erts_lc_ptab_is_rwlocked(ptab));
 
     ERTS_PTAB_LIST_DBG_CHK_DEL_LIST(ptab);
 
@@ -654,7 +654,7 @@ save_deleted_element(ErtsPTab *ptab, ErtsPTabElementCommon *ptab_el)
     ptdep->u.element.id = ptab_el->id;
     ptdep->u.element.inserted = ptab_el->u.alive.started_interval;
     ptdep->u.element.deleted =
-	erts_smp_current_interval_nob(erts_ptab_interval(ptab));
+	erts_current_interval_nob(erts_ptab_interval(ptab));
 
     ptab->list.data.deleted.end->next = ptdep;
     ptab->list.data.deleted.end = ptdep;
@@ -678,7 +678,7 @@ erts_ptab_delete_element(ErtsPTab *ptab,
     pix = erts_ptab_id2pix(ptab, ptab_el->id);
 
     /* *Need* to be an managed thread */
-    ERTS_SMP_LC_ASSERT(erts_thr_progress_is_managed_thread());
+    ERTS_LC_ASSERT(erts_thr_progress_is_managed_thread());
 
     erts_ptab_rlock(ptab);
     maybe_save = ptab->list.data.deleted.end != NULL;
@@ -687,7 +687,7 @@ erts_ptab_delete_element(ErtsPTab *ptab,
 	erts_ptab_rwlock(ptab);
     }
 
-    erts_smp_atomic_set_relb(&ptab->r.o.tab[pix], ERTS_AINT_NULL);
+    erts_atomic_set_relb(&ptab->r.o.tab[pix], ERTS_AINT_NULL);
 
     if (ptab->r.o.free_id_data) {
 	Uint32 prev_data;
@@ -703,17 +703,17 @@ erts_ptab_delete_element(ErtsPTab *ptab,
 	ASSERT(pix == erts_ptab_data2pix(ptab, data));
 
 	do { 
-	    ix = (Uint32) erts_smp_atomic32_inc_read_relb(&ptab->vola.tile.fid_ix);
+	    ix = (Uint32) erts_atomic32_inc_read_relb(&ptab->vola.tile.fid_ix);
 	    ix = ix_to_free_id_data_ix(ptab, ix);
     
-	    prev_data = erts_smp_atomic32_cmpxchg_nob(&ptab->r.o.free_id_data[ix],
+	    prev_data = erts_atomic32_cmpxchg_nob(&ptab->r.o.free_id_data[ix],
 						      data,
 						      ptab->r.o.invalid_data);
 	}while ((Eterm)prev_data != ptab->r.o.invalid_data);
     }
 
-    ASSERT(erts_smp_atomic32_read_nob(&ptab->vola.tile.count) > 0);
-    erts_smp_atomic32_dec_relb(&ptab->vola.tile.count);
+    ASSERT(erts_atomic32_read_nob(&ptab->vola.tile.count) > 0);
+    erts_atomic32_dec_relb(&ptab->vola.tile.count);
 
     if (!maybe_save)
 	erts_ptab_runlock(ptab);
@@ -927,7 +927,7 @@ ptab_list_bif_engine(Process *c_p, Eterm *res_accp, Binary *mbp)
 				 sizeof(ErtsPTabDeletedElement));
 		ptlbdp->bif_invocation->ix = -1;
 		ptlbdp->bif_invocation->u.bif_invocation.interval
-		    = erts_smp_step_interval_nob(erts_ptab_interval(ptab));
+		    = erts_step_interval_nob(erts_ptab_interval(ptab));
 		ERTS_PTAB_LIST_DBG_CHK_DEL_LIST(ptab);
 
 		ptlbdp->bif_invocation->next = NULL;
@@ -968,12 +968,12 @@ ptab_list_bif_engine(Process *c_p, Eterm *res_accp, Binary *mbp)
 		locked = 1;
 	    }
 
-	    ERTS_SMP_LC_ASSERT(erts_smp_lc_ptab_is_rwlocked(ptab));
+	    ERTS_LC_ASSERT(erts_lc_ptab_is_rwlocked(ptab));
 	    ERTS_PTAB_LIST_DBG_TRACE(p->common.id, insp_table);
 
 	    if (cix != 0)
 		ptlbdp->chunk[cix].interval
-		    = erts_smp_step_interval_nob(erts_ptab_interval(ptab));
+		    = erts_step_interval_nob(erts_ptab_interval(ptab));
 	    else if (ptlbdp->bif_invocation)
 		ptlbdp->chunk[0].interval = *invocation_interval_p;
 	    /* else: interval is irrelevant */
@@ -1331,18 +1331,18 @@ static void assert_ptab_consistency(ErtsPTab *ptab)
 	int null_slots = 0;
 	
 	for (ix=0; ix < ptab->r.o.max; ix++) {
-	    if (erts_smp_atomic32_read_nob(&ptab->r.o.free_id_data[ix]) != ptab->r.o.invalid_data) {
+	    if (erts_atomic32_read_nob(&ptab->r.o.free_id_data[ix]) != ptab->r.o.invalid_data) {
 		++free_pids;
-		data = erts_smp_atomic32_read_nob(&ptab->r.o.free_id_data[ix]);
+		data = erts_atomic32_read_nob(&ptab->r.o.free_id_data[ix]);
 		pix = erts_ptab_data2pix(ptab, (Eterm) data);
 		ASSERT(erts_ptab_pix2intptr_nob(ptab, pix) == ERTS_AINT_NULL);
 	    }
-	    if (erts_smp_atomic_read_nob(&ptab->r.o.tab[ix]) == ERTS_AINT_NULL) {
+	    if (erts_atomic_read_nob(&ptab->r.o.tab[ix]) == ERTS_AINT_NULL) {
 		++null_slots;
 	    }
 	}	
 	ASSERT(free_pids == null_slots);
-	ASSERT(free_pids == ptab->r.o.max - erts_smp_atomic32_read_nob(&ptab->vola.tile.count));
+	ASSERT(free_pids == ptab->r.o.max - erts_atomic32_read_nob(&ptab->vola.tile.count));
     }
 #endif
 }
@@ -1366,7 +1366,7 @@ erts_ptab_test_next_id(ErtsPTab *ptab, int set, Uint next)
 	    Uint32 i, max_ix, num, stop_id_ix;
 	    max_ix = ptab->r.o.max - 1;
 	    num = next;
-	    id_ix = (Uint32) erts_smp_atomic32_read_nob(&ptab->vola.tile.aid_ix);
+	    id_ix = (Uint32) erts_atomic32_read_nob(&ptab->vola.tile.aid_ix);
 
 	    for (i=0; i <= max_ix; ++i) {
 		Uint32 pix;
@@ -1380,26 +1380,26 @@ erts_ptab_test_next_id(ErtsPTab *ptab, int set, Uint next)
 		if (ERTS_AINT_NULL == erts_ptab_pix2intptr_nob(ptab, pix)) {
 		    ++id_ix;
 		    dix = ix_to_free_id_data_ix(ptab, id_ix);
-		    erts_smp_atomic32_set_nob(&ptab->r.o.free_id_data[dix], num);
+		    erts_atomic32_set_nob(&ptab->r.o.free_id_data[dix], num);
 		    ASSERT(pix == erts_ptab_data2pix(ptab, num));
 		}
 	    }
-	    erts_smp_atomic32_set_nob(&ptab->vola.tile.fid_ix, id_ix);
+	    erts_atomic32_set_nob(&ptab->vola.tile.fid_ix, id_ix);
 
 	    /* Write invalid_data in rest of free_id_data[]: */
-	    stop_id_ix = (1 + erts_smp_atomic32_read_nob(&ptab->vola.tile.aid_ix)) & max_ix;
+	    stop_id_ix = (1 + erts_atomic32_read_nob(&ptab->vola.tile.aid_ix)) & max_ix;
 	    while (1) {
 		id_ix = (id_ix+1) & max_ix;
 		if (id_ix == stop_id_ix)
 		    break;
 		dix = ix_to_free_id_data_ix(ptab, id_ix);
-		erts_smp_atomic32_set_nob(&ptab->r.o.free_id_data[dix],
+		erts_atomic32_set_nob(&ptab->r.o.free_id_data[dix],
 					  ptab->r.o.invalid_data);
 	    }
 	}
-	id_ix = (Uint32) erts_smp_atomic32_read_nob(&ptab->vola.tile.aid_ix) + 1;
+	id_ix = (Uint32) erts_atomic32_read_nob(&ptab->vola.tile.aid_ix) + 1;
 	dix = ix_to_free_id_data_ix(ptab, id_ix);
-	res = (Sint) erts_smp_atomic32_read_nob(&ptab->r.o.free_id_data[dix]);
+	res = (Sint) erts_atomic32_read_nob(&ptab->r.o.free_id_data[dix]);
     }
     else {
 	/* Deprecated legacy algorithm... */
@@ -1616,11 +1616,11 @@ debug_ptab_list_verify_all_pids(ErtsPTabListBifData *ptlbdp)
 static void
 debug_ptab_list_check_del_list(ErtsPTab *ptab)
 {
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_ptab_is_rwlocked(ptab));
+    ERTS_LC_ASSERT(erts_lc_ptab_is_rwlocked(ptab));
     if (!ptab->list.data.deleted.start)
 	ERTS_PTAB_LIST_ASSERT(!ptab->list.data.deleted.end);
     else {
-	Uint64 curr_interval = erts_smp_current_interval_nob(erts_ptab_interval(ptab));
+	Uint64 curr_interval = erts_current_interval_nob(erts_ptab_interval(ptab));
 	Uint64 *prev_x_interval_p = NULL;
 	ErtsPTabDeletedElement *ptdep;
 
diff --git a/erts/emulator/beam/erl_ptab.h b/erts/emulator/beam/erl_ptab.h
index fecfd96ab0..4858cc8ab8 100644
--- a/erts/emulator/beam/erl_ptab.h
+++ b/erts/emulator/beam/erl_ptab.h
@@ -60,7 +60,7 @@ typedef struct {
     } refc;
     ErtsTracer tracer;
     Uint trace_flags;
-    erts_smp_atomic_t timer;
+    erts_atomic_t timer;
     union {
 	/* --- While being alive --- */
 	struct {
@@ -78,7 +78,7 @@ typedef struct {
 typedef struct ErtsPTabDeletedElement_ ErtsPTabDeletedElement;
 
 typedef struct {
-    erts_smp_rwmtx_t rwmtx;
+    erts_rwmtx_t rwmtx;
     erts_interval_t interval;
     struct {
 	ErtsPTabDeletedElement *start;
@@ -88,15 +88,15 @@ typedef struct {
 } ErtsPTabListData;
 
 typedef struct {
-    erts_smp_atomic64_t last_data;
-    erts_smp_atomic32_t count;
-    erts_smp_atomic32_t aid_ix;
-    erts_smp_atomic32_t fid_ix;
+    erts_atomic64_t last_data;
+    erts_atomic32_t count;
+    erts_atomic32_t aid_ix;
+    erts_atomic32_t fid_ix;
 } ErtsPTabVolatileData;
 
 typedef struct {
-    erts_smp_atomic_t *tab;
-    erts_smp_atomic32_t *free_id_data;
+    erts_atomic_t *tab;
+    erts_atomic32_t *free_id_data;
     Uint32 max;
     Uint32 pix_mask;
     Uint32 pix_cl_mask;
@@ -223,8 +223,8 @@ ERTS_GLB_INLINE void erts_ptab_runlock(ErtsPTab *ptab);
 ERTS_GLB_INLINE void erts_ptab_rwlock(ErtsPTab *ptab);
 ERTS_GLB_INLINE int erts_ptab_tryrwlock(ErtsPTab *ptab);
 ERTS_GLB_INLINE void erts_ptab_rwunlock(ErtsPTab *ptab);
-ERTS_GLB_INLINE int erts_smp_lc_ptab_is_rlocked(ErtsPTab *ptab);
-ERTS_GLB_INLINE int erts_smp_lc_ptab_is_rwlocked(ErtsPTab *ptab);
+ERTS_GLB_INLINE int erts_lc_ptab_is_rlocked(ErtsPTab *ptab);
+ERTS_GLB_INLINE int erts_lc_ptab_is_rwlocked(ErtsPTab *ptab);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
@@ -245,7 +245,7 @@ ERTS_GLB_INLINE int
 erts_ptab_count(ErtsPTab *ptab)
 {
     int max = ptab->r.o.max;
-    erts_aint32_t res = erts_smp_atomic32_read_nob(&ptab->vola.tile.count);
+    erts_aint32_t res = erts_atomic32_read_nob(&ptab->vola.tile.count);
     if (max == ERTS_PTAB_MAX_SIZE) {
 	max--;
 	res--;
@@ -352,25 +352,25 @@ erts_ptab_id2data(ErtsPTab *ptab, Eterm id)
 ERTS_GLB_INLINE erts_aint_t erts_ptab_pix2intptr_nob(ErtsPTab *ptab, int ix)
 {
     ASSERT(0 <= ix && ix < ptab->r.o.max);
-    return erts_smp_atomic_read_nob(&ptab->r.o.tab[ix]);
+    return erts_atomic_read_nob(&ptab->r.o.tab[ix]);
 }
 
 ERTS_GLB_INLINE erts_aint_t erts_ptab_pix2intptr_ddrb(ErtsPTab *ptab, int ix)
 {
     ASSERT(0 <= ix && ix < ptab->r.o.max);
-    return erts_smp_atomic_read_ddrb(&ptab->r.o.tab[ix]);
+    return erts_atomic_read_ddrb(&ptab->r.o.tab[ix]);
 }
 
 ERTS_GLB_INLINE erts_aint_t erts_ptab_pix2intptr_rb(ErtsPTab *ptab, int ix)
 {
     ASSERT(0 <= ix && ix < ptab->r.o.max);
-    return erts_smp_atomic_read_rb(&ptab->r.o.tab[ix]);
+    return erts_atomic_read_rb(&ptab->r.o.tab[ix]);
 }
 
 ERTS_GLB_INLINE erts_aint_t erts_ptab_pix2intptr_acqb(ErtsPTab *ptab, int ix)
 {
     ASSERT(0 <= ix && ix < ptab->r.o.max);
-    return erts_smp_atomic_read_acqb(&ptab->r.o.tab[ix]);
+    return erts_atomic_read_acqb(&ptab->r.o.tab[ix]);
 }
 
 ERTS_GLB_INLINE void erts_ptab_atmc_inc_refc(ErtsPTabElementCommon *ptab_el)
@@ -386,11 +386,9 @@ ERTS_GLB_INLINE void erts_ptab_atmc_inc_refc(ErtsPTabElementCommon *ptab_el)
 ERTS_GLB_INLINE Sint erts_ptab_atmc_dec_test_refc(ErtsPTabElementCommon *ptab_el)
 {
     erts_aint_t refc = erts_atomic_dec_read_relb(&ptab_el->refc.atmc);
-    ERTS_SMP_LC_ASSERT(refc >= 0);
-#ifdef ERTS_SMP
+    ERTS_LC_ASSERT(refc >= 0);
     if (refc == 0)
 	ETHR_MEMBAR(ETHR_LoadLoad|ETHR_LoadStore);
-#endif
     return (Sint) refc;
 }
 
@@ -399,7 +397,7 @@ ERTS_GLB_INLINE Sint erts_ptab_atmc_add_test_refc(ErtsPTabElementCommon *ptab_el
 {
     erts_aint_t refc = erts_atomic_add_read_mb(&ptab_el->refc.atmc,
 					       (erts_aint_t) add_refc);
-    ERTS_SMP_LC_ASSERT(refc >= 0);
+    ERTS_LC_ASSERT(refc >= 0);
     return (Sint) refc;
 }
 
@@ -417,7 +415,7 @@ ERTS_GLB_INLINE void erts_ptab_inc_refc(ErtsPTabElementCommon *ptab_el)
 ERTS_GLB_INLINE Sint erts_ptab_dec_test_refc(ErtsPTabElementCommon *ptab_el)
 {
     Sint refc = --ptab_el->refc.sint;
-    ERTS_SMP_LC_ASSERT(refc >= 0);
+    ERTS_LC_ASSERT(refc >= 0);
     return refc;
 }
 
@@ -425,7 +423,7 @@ ERTS_GLB_INLINE Sint erts_ptab_add_test_refc(ErtsPTabElementCommon *ptab_el,
 					     Sint add_refc)
 {
     ptab_el->refc.sint += add_refc;
-    ERTS_SMP_LC_ASSERT(ptab_el->refc.sint >= 0);
+    ERTS_LC_ASSERT(ptab_el->refc.sint >= 0);
     return (Sint) ptab_el->refc.sint;
 }
 
@@ -436,42 +434,42 @@ ERTS_GLB_INLINE Sint erts_ptab_read_refc(ErtsPTabElementCommon *ptab_el)
 
 ERTS_GLB_INLINE void erts_ptab_rlock(ErtsPTab *ptab)
 {
-    erts_smp_rwmtx_rlock(&ptab->list.data.rwmtx);
+    erts_rwmtx_rlock(&ptab->list.data.rwmtx);
 }
 
 ERTS_GLB_INLINE int erts_ptab_tryrlock(ErtsPTab *ptab)
 {
-    return erts_smp_rwmtx_tryrlock(&ptab->list.data.rwmtx);
+    return erts_rwmtx_tryrlock(&ptab->list.data.rwmtx);
 }
 
 ERTS_GLB_INLINE void erts_ptab_runlock(ErtsPTab *ptab)
 {
-    erts_smp_rwmtx_runlock(&ptab->list.data.rwmtx);
+    erts_rwmtx_runlock(&ptab->list.data.rwmtx);
 }
 
 ERTS_GLB_INLINE void erts_ptab_rwlock(ErtsPTab *ptab)
 {
-    erts_smp_rwmtx_rwlock(&ptab->list.data.rwmtx);
+    erts_rwmtx_rwlock(&ptab->list.data.rwmtx);
 }
 
 ERTS_GLB_INLINE int erts_ptab_tryrwlock(ErtsPTab *ptab)
 {
-    return erts_smp_rwmtx_tryrwlock(&ptab->list.data.rwmtx);
+    return erts_rwmtx_tryrwlock(&ptab->list.data.rwmtx);
 }
 
 ERTS_GLB_INLINE void erts_ptab_rwunlock(ErtsPTab *ptab)
 {
-    erts_smp_rwmtx_rwunlock(&ptab->list.data.rwmtx);
+    erts_rwmtx_rwunlock(&ptab->list.data.rwmtx);
 }
 
-ERTS_GLB_INLINE int erts_smp_lc_ptab_is_rlocked(ErtsPTab *ptab)
+ERTS_GLB_INLINE int erts_lc_ptab_is_rlocked(ErtsPTab *ptab)
 {
-    return erts_smp_lc_rwmtx_is_rlocked(&ptab->list.data.rwmtx);
+    return erts_lc_rwmtx_is_rlocked(&ptab->list.data.rwmtx);
 }
 
-ERTS_GLB_INLINE int erts_smp_lc_ptab_is_rwlocked(ErtsPTab *ptab)
+ERTS_GLB_INLINE int erts_lc_ptab_is_rwlocked(ErtsPTab *ptab)
 {
-    return erts_smp_lc_rwmtx_is_rwlocked(&ptab->list.data.rwmtx);
+    return erts_lc_rwmtx_is_rwlocked(&ptab->list.data.rwmtx);
 }
 
 #endif
diff --git a/erts/emulator/beam/erl_sched_spec_pre_alloc.c b/erts/emulator/beam/erl_sched_spec_pre_alloc.c
index 96238318c9..ab204303d7 100644
--- a/erts/emulator/beam/erl_sched_spec_pre_alloc.c
+++ b/erts/emulator/beam/erl_sched_spec_pre_alloc.c
@@ -32,13 +32,12 @@
 #  include "config.h"
 #endif
 
-#ifdef ERTS_SMP
 
 #include "erl_process.h"
 #include "erl_thr_progress.h"
 
 erts_sspa_data_t *
-erts_sspa_create(size_t blk_sz, int pa_size)
+erts_sspa_create(size_t blk_sz, int pa_size, int nthreads, const char* name)
 {
     erts_sspa_data_t *data;
     size_t tot_size;
@@ -49,22 +48,30 @@ erts_sspa_create(size_t blk_sz, int pa_size)
     int no_blocks = pa_size;
     int no_blocks_per_chunk;
 
-    if (erts_no_schedulers == 1)
+    if (!name) { /* schedulers only variant */
+        ASSERT(!nthreads);
+        nthreads = erts_no_schedulers;
+    }
+    else {
+        ASSERT(nthreads > 0);
+    }
+
+    if (nthreads == 1)
 	no_blocks_per_chunk = no_blocks;
     else {
 	int extra = (no_blocks - 1)/4 + 1;
 	if (extra == 0)
 	    extra = 1;
 	no_blocks_per_chunk = no_blocks;
-	no_blocks_per_chunk += extra*erts_no_schedulers;
-	no_blocks_per_chunk /= erts_no_schedulers;
+	no_blocks_per_chunk += extra * nthreads;
+	no_blocks_per_chunk /= nthreads;
     }
-    no_blocks = no_blocks_per_chunk * erts_no_schedulers;
+    no_blocks = no_blocks_per_chunk * nthreads;
     chunk_mem_size = ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(erts_sspa_chunk_header_t));
     chunk_mem_size += blk_sz * no_blocks_per_chunk;
     chunk_mem_size = ERTS_ALC_CACHE_LINE_ALIGN_SIZE(chunk_mem_size);
     tot_size = ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(erts_sspa_data_t));
-    tot_size += chunk_mem_size*erts_no_schedulers;
+    tot_size += chunk_mem_size * nthreads;
 
     p = erts_alloc_permanent_cache_aligned(ERTS_ALC_T_PRE_ALLOC_DATA, tot_size);
     data = (erts_sspa_data_t *) p;
@@ -73,10 +80,16 @@ erts_sspa_create(size_t blk_sz, int pa_size)
 
     data->chunks_mem_size = chunk_mem_size;
     data->start = chunk_start;
-    data->end = chunk_start + chunk_mem_size*erts_no_schedulers;
+    data->end = chunk_start + chunk_mem_size * nthreads;
+    data->nthreads = nthreads;
+
+    if (name) { /* thread variant */
+        erts_tsd_key_create(&data->tsd_key, (char*)name);
+        erts_atomic_init_nob(&data->id_generator, 0);
+    }
 
     /* Initialize all chunks */
-    for (cix = 0; cix < erts_no_schedulers; cix++) {
+    for (cix = 0; cix < nthreads; cix++) {
 	erts_sspa_chunk_t *chnk = erts_sspa_cix2chunk(data, cix);
 	erts_sspa_chunk_header_t *chdr = &chnk->aligned.header;
 	erts_sspa_blk_t *blk;
@@ -325,4 +338,3 @@ erts_sspa_process_remote_frees(erts_sspa_chunk_header_t *chdr,
     return res;
 }
 
-#endif /* ERTS_SMP */
diff --git a/erts/emulator/beam/erl_sched_spec_pre_alloc.h b/erts/emulator/beam/erl_sched_spec_pre_alloc.h
index 7808d7d438..d232db0e69 100644
--- a/erts/emulator/beam/erl_sched_spec_pre_alloc.h
+++ b/erts/emulator/beam/erl_sched_spec_pre_alloc.h
@@ -31,7 +31,6 @@
 #ifndef ERTS_SCHED_SPEC_PRE_ALLOC_H__
 #define ERTS_SCHED_SPEC_PRE_ALLOC_H__
 
-#ifdef ERTS_SMP
 
 #undef ERL_THR_PROGRESS_TSD_TYPE_ONLY
 #define ERL_THR_PROGRESS_TSD_TYPE_ONLY
@@ -60,6 +59,11 @@ typedef struct {
     char *start;
     char *end;
     int chunks_mem_size;
+    int nthreads;
+
+    /* Used only by thread variant: */
+    erts_tsd_key_t tsd_key;
+    erts_atomic_t id_generator;
 } erts_sspa_data_t;
 
 typedef union erts_sspa_blk_t_ erts_sspa_blk_t;
@@ -141,7 +145,9 @@ check_local_list(erts_sspa_chunk_header_t *chdr)
 #endif
 
 erts_sspa_data_t *erts_sspa_create(size_t blk_sz,
-				   int pa_size);
+				   int pa_size,
+                                   int nthreads,
+                                   const char* name);
 void erts_sspa_remote_free(erts_sspa_chunk_header_t *chdr,
 			   erts_sspa_blk_t *blk,
 			   int cinit);
@@ -159,7 +165,7 @@ ERTS_GLB_INLINE int erts_sspa_free(erts_sspa_data_t *data, int cix, char *blk);
 ERTS_GLB_INLINE erts_sspa_chunk_t *
 erts_sspa_cix2chunk(erts_sspa_data_t *data, int cix)
 {
-    ASSERT(0 <= cix && cix < erts_no_schedulers);
+    ASSERT(0 <= cix && cix < data->nthreads);
     return (erts_sspa_chunk_t *) (data->start + cix*data->chunks_mem_size);
 }
 
@@ -172,7 +178,7 @@ erts_sspa_ptr2cix(erts_sspa_data_t *data, void *ptr)
 	return -1;
     diff = ((char *) ptr) - data->start;
     cix = (int) diff / data->chunks_mem_size;
-    ASSERT(0 <= cix && cix < erts_no_schedulers);
+    ASSERT(0 <= cix && cix < data->nthreads);
     return cix;
 }
 
@@ -236,6 +242,5 @@ erts_sspa_free(erts_sspa_data_t *data, int cix, char *cblk)
 
 #endif /* ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
-#endif /* ERTS_SMP */
 
 #endif /* ERTS_SCHED_SPEC_PRE_ALLOC_H__ */
diff --git a/erts/emulator/beam/erl_smp.h b/erts/emulator/beam/erl_smp.h
deleted file mode 100644
index 696bdbdaf1..0000000000
--- a/erts/emulator/beam/erl_smp.h
+++ /dev/null
@@ -1,1585 +0,0 @@
-/*
- * %CopyrightBegin%
- *
- * Copyright Ericsson AB 2005-2017. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * %CopyrightEnd%
- */
-/*
- * SMP interface to ethread library.
- * This is essentially "sed s/erts_/erts_smp_/g < erl_threads.h > erl_smp.h",
- * plus changes to NOP operations when ERTS_SMP is disabled.
- * Author: Mikael Pettersson
- */
-#ifndef ERL_SMP_H
-#define ERL_SMP_H
-#include "erl_threads.h"
-
-#ifdef ERTS_ENABLE_LOCK_POSITION
-#define erts_smp_mtx_lock(L) erts_smp_mtx_lock_x(L, __FILE__, __LINE__)
-#define erts_smp_mtx_trylock(L) erts_smp_mtx_trylock_x(L, __FILE__, __LINE__)
-#define erts_smp_spin_lock(L) erts_smp_spin_lock_x(L, __FILE__, __LINE__)
-#define erts_smp_rwmtx_tryrlock(L) erts_smp_rwmtx_tryrlock_x(L, __FILE__, __LINE__)
-#define erts_smp_rwmtx_rlock(L) erts_smp_rwmtx_rlock_x(L, __FILE__, __LINE__)
-#define erts_smp_rwmtx_tryrwlock(L) erts_smp_rwmtx_tryrwlock_x(L, __FILE__, __LINE__)
-#define erts_smp_rwmtx_rwlock(L) erts_smp_rwmtx_rwlock_x(L, __FILE__, __LINE__)
-#define erts_smp_read_lock(L) erts_smp_read_lock_x(L, __FILE__, __LINE__)
-#define erts_smp_write_lock(L) erts_smp_write_lock_x(L, __FILE__, __LINE__)
-#endif
-
-
-#ifdef ERTS_SMP
-#define ERTS_SMP_THR_OPTS_DEFAULT_INITER ERTS_THR_OPTS_DEFAULT_INITER
-typedef erts_thr_opts_t erts_smp_thr_opts_t;
-typedef erts_thr_init_data_t erts_smp_thr_init_data_t;
-typedef erts_tid_t erts_smp_tid_t;
-typedef erts_mtx_t erts_smp_mtx_t;
-typedef erts_cnd_t erts_smp_cnd_t;
-#define ERTS_SMP_RWMTX_OPT_DEFAULT_INITER ERTS_RWMTX_OPT_DEFAULT_INITER
-#define ERTS_SMP_RWMTX_TYPE_NORMAL ERTS_RWMTX_TYPE_NORMAL
-#define ERTS_SMP_RWMTX_TYPE_FREQUENT_READ ERTS_RWMTX_TYPE_FREQUENT_READ
-#define ERTS_SMP_RWMTX_TYPE_EXTREMELY_FREQUENT_READ \
-  ERTS_RWMTX_TYPE_EXTREMELY_FREQUENT_READ
-#define ERTS_SMP_RWMTX_LONG_LIVED ERTS_RWMTX_LONG_LIVED
-#define ERTS_SMP_RWMTX_SHORT_LIVED ERTS_RWMTX_SHORT_LIVED
-#define ERTS_SMP_RWMTX_UNKNOWN_LIVED ERTS_RWMTX_UNKNOWN_LIVED
-typedef erts_rwmtx_opt_t erts_smp_rwmtx_opt_t;
-typedef erts_rwmtx_t erts_smp_rwmtx_t;
-typedef erts_tsd_key_t erts_smp_tsd_key_t;
-#define erts_smp_dw_atomic_t erts_dw_atomic_t
-#define erts_smp_atomic_t erts_atomic_t
-#define erts_smp_atomic32_t erts_atomic32_t
-#define erts_smp_atomic64_t erts_atomic64_t
-typedef erts_spinlock_t erts_smp_spinlock_t;
-typedef erts_rwlock_t erts_smp_rwlock_t;
-void erts_thr_fatal_error(int, char *); /* implemented in erl_init.c */
-
-#define ERTS_SMP_MEMORY_BARRIER ERTS_THR_MEMORY_BARRIER
-#define ERTS_SMP_WRITE_MEMORY_BARRIER ERTS_THR_WRITE_MEMORY_BARRIER
-#define ERTS_SMP_READ_MEMORY_BARRIER ERTS_THR_READ_MEMORY_BARRIER
-#define ERTS_SMP_DATA_DEPENDENCY_READ_MEMORY_BARRIER ERTS_THR_DATA_DEPENDENCY_READ_MEMORY_BARRIER
-
-#else /* #ifdef ERTS_SMP */
-
-#define ERTS_SMP_THR_OPTS_DEFAULT_INITER {0}
-typedef int erts_smp_thr_opts_t;
-typedef int erts_smp_thr_init_data_t;
-typedef int erts_smp_tid_t;
-typedef int erts_smp_mtx_t;
-typedef int erts_smp_cnd_t;
-#define ERTS_SMP_RWMTX_OPT_DEFAULT_INITER {0}
-#define ERTS_SMP_RWMTX_TYPE_NORMAL 0
-#define ERTS_SMP_RWMTX_TYPE_FREQUENT_READ 0
-#define ERTS_SMP_RWMTX_TYPE_EXTREMELY_FREQUENT_READ 0
-#define ERTS_SMP_RWMTX_LONG_LIVED 0
-#define ERTS_SMP_RWMTX_SHORT_LIVED 0
-#define ERTS_SMP_RWMTX_UNKNOWN_LIVED 0
-typedef struct {
-    char type;
-    char lived;
-    int main_spincount;
-    int aux_spincount;
-} erts_smp_rwmtx_opt_t;
-typedef int erts_smp_rwmtx_t;
-typedef int erts_smp_tsd_key_t;
-#define erts_smp_dw_atomic_t erts_no_dw_atomic_t
-#define erts_smp_atomic_t erts_no_atomic_t
-#define erts_smp_atomic32_t erts_no_atomic32_t
-#define erts_smp_atomic64_t erts_no_atomic64_t
-#if __GNUC__ > 2
-typedef struct { } erts_smp_spinlock_t;
-typedef struct { } erts_smp_rwlock_t;
-#else
-typedef struct { int gcc_is_buggy; } erts_smp_spinlock_t;
-typedef struct { int gcc_is_buggy; } erts_smp_rwlock_t;
-#endif
-
-#define ERTS_SMP_MEMORY_BARRIER
-#define ERTS_SMP_WRITE_MEMORY_BARRIER
-#define ERTS_SMP_READ_MEMORY_BARRIER
-#define ERTS_SMP_DATA_DEPENDENCY_READ_MEMORY_BARRIER
-
-#endif /* #ifdef ERTS_SMP */
-
-ERTS_GLB_INLINE void erts_smp_thr_init(erts_smp_thr_init_data_t *id);
-ERTS_GLB_INLINE void erts_smp_thr_create(erts_smp_tid_t *tid,
-					 void * (*func)(void *),
-					 void *arg,
-					 erts_smp_thr_opts_t *opts);
-ERTS_GLB_INLINE void erts_smp_thr_join(erts_smp_tid_t tid, void **thr_res);
-ERTS_GLB_INLINE void erts_smp_thr_detach(erts_smp_tid_t tid);
-ERTS_GLB_INLINE void erts_smp_thr_exit(void *res);
-ERTS_GLB_INLINE void erts_smp_install_exit_handler(void (*exit_handler)(void));
-ERTS_GLB_INLINE erts_smp_tid_t erts_smp_thr_self(void);
-ERTS_GLB_INLINE int erts_smp_equal_tids(erts_smp_tid_t x, erts_smp_tid_t y);
-#ifdef ERTS_HAVE_REC_MTX_INIT
-#define ERTS_SMP_HAVE_REC_MTX_INIT 1
-ERTS_GLB_INLINE void erts_smp_rec_mtx_init(erts_smp_mtx_t *mtx);
-#endif
-ERTS_GLB_INLINE void erts_smp_mtx_init(erts_smp_mtx_t *mtx,
-                                       char *name,
-                                       Eterm extra,
-                                       erts_lock_flags_t flags);
-ERTS_GLB_INLINE void erts_smp_mtx_init_locked(erts_smp_mtx_t *mtx,
-                                               char *name,
-                                               Eterm extra,
-                                               erts_lock_flags_t flags);
-ERTS_GLB_INLINE void erts_smp_mtx_destroy(erts_smp_mtx_t *mtx);
-#ifdef ERTS_ENABLE_LOCK_POSITION
-ERTS_GLB_INLINE int erts_smp_mtx_trylock_x(erts_smp_mtx_t *mtx, char *file, unsigned int line);
-ERTS_GLB_INLINE void erts_smp_mtx_lock_x(erts_smp_mtx_t *mtx, char *file, unsigned int line);
-#else
-ERTS_GLB_INLINE int erts_smp_mtx_trylock(erts_smp_mtx_t *mtx);
-ERTS_GLB_INLINE void erts_smp_mtx_lock(erts_smp_mtx_t *mtx);
-#endif
-ERTS_GLB_INLINE void erts_smp_mtx_unlock(erts_smp_mtx_t *mtx);
-ERTS_GLB_INLINE int erts_smp_lc_mtx_is_locked(erts_smp_mtx_t *mtx);
-ERTS_GLB_INLINE void erts_smp_cnd_init(erts_smp_cnd_t *cnd);
-ERTS_GLB_INLINE void erts_smp_cnd_destroy(erts_smp_cnd_t *cnd);
-ERTS_GLB_INLINE void erts_smp_cnd_wait(erts_smp_cnd_t *cnd,
-					   erts_smp_mtx_t *mtx);
-ERTS_GLB_INLINE void erts_smp_cnd_signal(erts_smp_cnd_t *cnd);
-ERTS_GLB_INLINE void erts_smp_cnd_broadcast(erts_smp_cnd_t *cnd);
-ERTS_GLB_INLINE void erts_smp_rwmtx_set_reader_group(int no);
-ERTS_GLB_INLINE void erts_smp_rwmtx_init_opt(erts_smp_rwmtx_t *rwmtx,
-                                             erts_smp_rwmtx_opt_t *opt,
-                                             char *name,
-                                             Eterm extra,
-                                             erts_lock_flags_t flags);
-ERTS_GLB_INLINE void erts_smp_rwmtx_init(erts_smp_rwmtx_t *rwmtx,
-                                         char *name,
-                                         Eterm extra,
-                                         erts_lock_flags_t flags);
-ERTS_GLB_INLINE void erts_smp_rwmtx_destroy(erts_smp_rwmtx_t *rwmtx);
-#ifdef ERTS_ENABLE_LOCK_POSITION
-ERTS_GLB_INLINE int erts_smp_rwmtx_tryrlock_x(erts_smp_rwmtx_t *rwmtx, char *file, unsigned int line);
-ERTS_GLB_INLINE void erts_smp_rwmtx_rlock_x(erts_smp_rwmtx_t *rwmtx, char *file, unsigned int line);
-ERTS_GLB_INLINE void erts_smp_rwmtx_rwlock_x(erts_smp_rwmtx_t *rwmtx, char *file, unsigned int line);
-ERTS_GLB_INLINE int erts_smp_rwmtx_tryrwlock_x(erts_smp_rwmtx_t *rwmtx, char *file, unsigned int line);
-#else
-ERTS_GLB_INLINE int erts_smp_rwmtx_tryrlock(erts_smp_rwmtx_t *rwmtx);
-ERTS_GLB_INLINE void erts_smp_rwmtx_rlock(erts_smp_rwmtx_t *rwmtx);
-ERTS_GLB_INLINE void erts_smp_rwmtx_rwlock(erts_smp_rwmtx_t *rwmtx);
-ERTS_GLB_INLINE int erts_smp_rwmtx_tryrwlock(erts_smp_rwmtx_t *rwmtx);
-#endif
-ERTS_GLB_INLINE void erts_smp_rwmtx_runlock(erts_smp_rwmtx_t *rwmtx);
-ERTS_GLB_INLINE void erts_smp_rwmtx_rwunlock(erts_smp_rwmtx_t *rwmtx);
-ERTS_GLB_INLINE int erts_smp_lc_rwmtx_is_rlocked(erts_smp_rwmtx_t *mtx);
-ERTS_GLB_INLINE int erts_smp_lc_rwmtx_is_rwlocked(erts_smp_rwmtx_t *mtx);
-ERTS_GLB_INLINE void erts_smp_spinlock_init(erts_smp_spinlock_t *lock,
-                                            char *name,
-                                            Eterm extra,
-                                            erts_lock_flags_t flags);
-ERTS_GLB_INLINE void erts_smp_spinlock_destroy(erts_smp_spinlock_t *lock);
-ERTS_GLB_INLINE void erts_smp_spin_unlock(erts_smp_spinlock_t *lock);
-#ifdef ERTS_ENABLE_LOCK_POSITION
-ERTS_GLB_INLINE void erts_smp_spin_lock_x(erts_smp_spinlock_t *lock, char *file, unsigned int line);
-#else
-ERTS_GLB_INLINE void erts_smp_spin_lock(erts_smp_spinlock_t *lock);
-#endif
-ERTS_GLB_INLINE int erts_smp_lc_spinlock_is_locked(erts_smp_spinlock_t *lock);
-ERTS_GLB_INLINE void erts_smp_rwlock_init(erts_smp_rwlock_t *lock,
-                                          char *name,
-                                          Eterm extra,
-                                          erts_lock_flags_t flags);
-ERTS_GLB_INLINE void erts_smp_rwlock_destroy(erts_smp_rwlock_t *lock);
-ERTS_GLB_INLINE void erts_smp_read_unlock(erts_smp_rwlock_t *lock);
-#ifdef ERTS_ENABLE_LOCK_POSITION
-ERTS_GLB_INLINE void erts_smp_read_lock_x(erts_smp_rwlock_t *lock, char *file, unsigned int line);
-ERTS_GLB_INLINE void erts_smp_write_lock_x(erts_smp_rwlock_t *lock, char *file, unsigned int line);
-#else
-ERTS_GLB_INLINE void erts_smp_read_lock(erts_smp_rwlock_t *lock);
-ERTS_GLB_INLINE void erts_smp_write_lock(erts_smp_rwlock_t *lock);
-#endif
-ERTS_GLB_INLINE void erts_smp_write_unlock(erts_smp_rwlock_t *lock);
-ERTS_GLB_INLINE int erts_smp_lc_rwlock_is_rlocked(erts_smp_rwlock_t *lock);
-ERTS_GLB_INLINE int erts_smp_lc_rwlock_is_rwlocked(erts_smp_rwlock_t *lock);
-ERTS_GLB_INLINE void erts_smp_tsd_key_create(erts_smp_tsd_key_t *keyp,
-					     char *keyname);
-ERTS_GLB_INLINE void erts_smp_tsd_key_delete(erts_smp_tsd_key_t key);
-ERTS_GLB_INLINE void erts_smp_tsd_set(erts_smp_tsd_key_t key, void *value);
-ERTS_GLB_INLINE void * erts_smp_tsd_get(erts_smp_tsd_key_t key);
-
-#ifdef ERTS_THR_HAVE_SIG_FUNCS
-#define ERTS_SMP_THR_HAVE_SIG_FUNCS 1
-ERTS_GLB_INLINE void erts_smp_thr_sigmask(int how,
-					  const sigset_t *set,
-					  sigset_t *oset);
-ERTS_GLB_INLINE void erts_smp_thr_sigwait(const sigset_t *set, int *sig);
-#endif /* #ifdef ERTS_THR_HAVE_SIG_FUNCS */
-
-/*
- * See "Documentation of atomics and memory barriers" at the top
- * of erl_threads.h for info on atomics.
- */
-
-#ifdef ERTS_SMP
-
-/* Double word size atomics */
-
-#define erts_smp_dw_atomic_init_nob erts_dw_atomic_init_nob
-#define erts_smp_dw_atomic_set_nob erts_dw_atomic_set_nob
-#define erts_smp_dw_atomic_read_nob erts_dw_atomic_read_nob
-#define erts_smp_dw_atomic_cmpxchg_nob erts_dw_atomic_cmpxchg_nob
-
-#define erts_smp_dw_atomic_init_mb erts_dw_atomic_init_mb
-#define erts_smp_dw_atomic_set_mb erts_dw_atomic_set_mb
-#define erts_smp_dw_atomic_read_mb erts_dw_atomic_read_mb
-#define erts_smp_dw_atomic_cmpxchg_mb erts_dw_atomic_cmpxchg_mb
-
-#define erts_smp_dw_atomic_init_acqb erts_dw_atomic_init_acqb
-#define erts_smp_dw_atomic_set_acqb erts_dw_atomic_set_acqb
-#define erts_smp_dw_atomic_read_acqb erts_dw_atomic_read_acqb
-#define erts_smp_dw_atomic_cmpxchg_acqb erts_dw_atomic_cmpxchg_acqb
-
-#define erts_smp_dw_atomic_init_relb erts_dw_atomic_init_relb
-#define erts_smp_dw_atomic_set_relb erts_dw_atomic_set_relb
-#define erts_smp_dw_atomic_read_relb erts_dw_atomic_read_relb
-#define erts_smp_dw_atomic_cmpxchg_relb erts_dw_atomic_cmpxchg_relb
-
-#define erts_smp_dw_atomic_init_ddrb erts_dw_atomic_init_ddrb
-#define erts_smp_dw_atomic_set_ddrb erts_dw_atomic_set_ddrb
-#define erts_smp_dw_atomic_read_ddrb erts_dw_atomic_read_ddrb
-#define erts_smp_dw_atomic_cmpxchg_ddrb erts_dw_atomic_cmpxchg_ddrb
-
-#define erts_smp_dw_atomic_init_rb erts_dw_atomic_init_rb
-#define erts_smp_dw_atomic_set_rb erts_dw_atomic_set_rb
-#define erts_smp_dw_atomic_read_rb erts_dw_atomic_read_rb
-#define erts_smp_dw_atomic_cmpxchg_rb erts_dw_atomic_cmpxchg_rb
-
-#define erts_smp_dw_atomic_init_wb erts_dw_atomic_init_wb
-#define erts_smp_dw_atomic_set_wb erts_dw_atomic_set_wb
-#define erts_smp_dw_atomic_read_wb erts_dw_atomic_read_wb
-#define erts_smp_dw_atomic_cmpxchg_wb erts_dw_atomic_cmpxchg_wb
-
-#define erts_smp_dw_atomic_set_dirty erts_dw_atomic_set_dirty
-#define erts_smp_dw_atomic_read_dirty erts_dw_atomic_read_dirty
-
-/* Word size atomics */
-
-#define erts_smp_atomic_init_nob erts_atomic_init_nob
-#define erts_smp_atomic_set_nob erts_atomic_set_nob
-#define erts_smp_atomic_read_nob erts_atomic_read_nob
-#define erts_smp_atomic_inc_read_nob erts_atomic_inc_read_nob
-#define erts_smp_atomic_dec_read_nob erts_atomic_dec_read_nob
-#define erts_smp_atomic_inc_nob erts_atomic_inc_nob
-#define erts_smp_atomic_dec_nob erts_atomic_dec_nob
-#define erts_smp_atomic_add_read_nob erts_atomic_add_read_nob
-#define erts_smp_atomic_add_nob erts_atomic_add_nob
-#define erts_smp_atomic_read_bor_nob erts_atomic_read_bor_nob
-#define erts_smp_atomic_read_band_nob erts_atomic_read_band_nob
-#define erts_smp_atomic_xchg_nob erts_atomic_xchg_nob
-#define erts_smp_atomic_cmpxchg_nob erts_atomic_cmpxchg_nob
-#define erts_smp_atomic_read_bset_nob erts_atomic_read_bset_nob
-
-#define erts_smp_atomic_init_mb erts_atomic_init_mb
-#define erts_smp_atomic_set_mb erts_atomic_set_mb
-#define erts_smp_atomic_read_mb erts_atomic_read_mb
-#define erts_smp_atomic_inc_read_mb erts_atomic_inc_read_mb
-#define erts_smp_atomic_dec_read_mb erts_atomic_dec_read_mb
-#define erts_smp_atomic_inc_mb erts_atomic_inc_mb
-#define erts_smp_atomic_dec_mb erts_atomic_dec_mb
-#define erts_smp_atomic_add_read_mb erts_atomic_add_read_mb
-#define erts_smp_atomic_add_mb erts_atomic_add_mb
-#define erts_smp_atomic_read_bor_mb erts_atomic_read_bor_mb
-#define erts_smp_atomic_read_band_mb erts_atomic_read_band_mb
-#define erts_smp_atomic_xchg_mb erts_atomic_xchg_mb
-#define erts_smp_atomic_cmpxchg_mb erts_atomic_cmpxchg_mb
-#define erts_smp_atomic_read_bset_mb erts_atomic_read_bset_mb
-
-#define erts_smp_atomic_init_acqb erts_atomic_init_acqb
-#define erts_smp_atomic_set_acqb erts_atomic_set_acqb
-#define erts_smp_atomic_read_acqb erts_atomic_read_acqb
-#define erts_smp_atomic_inc_read_acqb erts_atomic_inc_read_acqb
-#define erts_smp_atomic_dec_read_acqb erts_atomic_dec_read_acqb
-#define erts_smp_atomic_inc_acqb erts_atomic_inc_acqb
-#define erts_smp_atomic_dec_acqb erts_atomic_dec_acqb
-#define erts_smp_atomic_add_read_acqb erts_atomic_add_read_acqb
-#define erts_smp_atomic_add_acqb erts_atomic_add_acqb
-#define erts_smp_atomic_read_bor_acqb erts_atomic_read_bor_acqb
-#define erts_smp_atomic_read_band_acqb erts_atomic_read_band_acqb
-#define erts_smp_atomic_xchg_acqb erts_atomic_xchg_acqb
-#define erts_smp_atomic_cmpxchg_acqb erts_atomic_cmpxchg_acqb
-#define erts_smp_atomic_read_bset_acqb erts_atomic_read_bset_acqb
-
-#define erts_smp_atomic_init_relb erts_atomic_init_relb
-#define erts_smp_atomic_set_relb erts_atomic_set_relb
-#define erts_smp_atomic_read_relb erts_atomic_read_relb
-#define erts_smp_atomic_inc_read_relb erts_atomic_inc_read_relb
-#define erts_smp_atomic_dec_read_relb erts_atomic_dec_read_relb
-#define erts_smp_atomic_inc_relb erts_atomic_inc_relb
-#define erts_smp_atomic_dec_relb erts_atomic_dec_relb
-#define erts_smp_atomic_add_read_relb erts_atomic_add_read_relb
-#define erts_smp_atomic_add_relb erts_atomic_add_relb
-#define erts_smp_atomic_read_bor_relb erts_atomic_read_bor_relb
-#define erts_smp_atomic_read_band_relb erts_atomic_read_band_relb
-#define erts_smp_atomic_xchg_relb erts_atomic_xchg_relb
-#define erts_smp_atomic_cmpxchg_relb erts_atomic_cmpxchg_relb
-#define erts_smp_atomic_read_bset_relb erts_atomic_read_bset_relb
-
-#define erts_smp_atomic_init_ddrb erts_atomic_init_ddrb
-#define erts_smp_atomic_set_ddrb erts_atomic_set_ddrb
-#define erts_smp_atomic_read_ddrb erts_atomic_read_ddrb
-#define erts_smp_atomic_inc_read_ddrb erts_atomic_inc_read_ddrb
-#define erts_smp_atomic_dec_read_ddrb erts_atomic_dec_read_ddrb
-#define erts_smp_atomic_inc_ddrb erts_atomic_inc_ddrb
-#define erts_smp_atomic_dec_ddrb erts_atomic_dec_ddrb
-#define erts_smp_atomic_add_read_ddrb erts_atomic_add_read_ddrb
-#define erts_smp_atomic_add_ddrb erts_atomic_add_ddrb
-#define erts_smp_atomic_read_bor_ddrb erts_atomic_read_bor_ddrb
-#define erts_smp_atomic_read_band_ddrb erts_atomic_read_band_ddrb
-#define erts_smp_atomic_xchg_ddrb erts_atomic_xchg_ddrb
-#define erts_smp_atomic_cmpxchg_ddrb erts_atomic_cmpxchg_ddrb
-#define erts_smp_atomic_read_bset_ddrb erts_atomic_read_bset_ddrb
-
-#define erts_smp_atomic_init_rb erts_atomic_init_rb
-#define erts_smp_atomic_set_rb erts_atomic_set_rb
-#define erts_smp_atomic_read_rb erts_atomic_read_rb
-#define erts_smp_atomic_inc_read_rb erts_atomic_inc_read_rb
-#define erts_smp_atomic_dec_read_rb erts_atomic_dec_read_rb
-#define erts_smp_atomic_inc_rb erts_atomic_inc_rb
-#define erts_smp_atomic_dec_rb erts_atomic_dec_rb
-#define erts_smp_atomic_add_read_rb erts_atomic_add_read_rb
-#define erts_smp_atomic_add_rb erts_atomic_add_rb
-#define erts_smp_atomic_read_bor_rb erts_atomic_read_bor_rb
-#define erts_smp_atomic_read_band_rb erts_atomic_read_band_rb
-#define erts_smp_atomic_xchg_rb erts_atomic_xchg_rb
-#define erts_smp_atomic_cmpxchg_rb erts_atomic_cmpxchg_rb
-#define erts_smp_atomic_read_bset_rb erts_atomic_read_bset_rb
-
-#define erts_smp_atomic_init_wb erts_atomic_init_wb
-#define erts_smp_atomic_set_wb erts_atomic_set_wb
-#define erts_smp_atomic_read_wb erts_atomic_read_wb
-#define erts_smp_atomic_inc_read_wb erts_atomic_inc_read_wb
-#define erts_smp_atomic_dec_read_wb erts_atomic_dec_read_wb
-#define erts_smp_atomic_inc_wb erts_atomic_inc_wb
-#define erts_smp_atomic_dec_wb erts_atomic_dec_wb
-#define erts_smp_atomic_add_read_wb erts_atomic_add_read_wb
-#define erts_smp_atomic_add_wb erts_atomic_add_wb
-#define erts_smp_atomic_read_bor_wb erts_atomic_read_bor_wb
-#define erts_smp_atomic_read_band_wb erts_atomic_read_band_wb
-#define erts_smp_atomic_xchg_wb erts_atomic_xchg_wb
-#define erts_smp_atomic_cmpxchg_wb erts_atomic_cmpxchg_wb
-#define erts_smp_atomic_read_bset_wb erts_atomic_read_bset_wb
-
-#define erts_smp_atomic_set_dirty erts_atomic_set_dirty
-#define erts_smp_atomic_read_dirty erts_atomic_read_dirty
-
-/* 32-bit atomics */
-
-#define erts_smp_atomic32_init_nob erts_atomic32_init_nob
-#define erts_smp_atomic32_set_nob erts_atomic32_set_nob
-#define erts_smp_atomic32_read_nob erts_atomic32_read_nob
-#define erts_smp_atomic32_inc_read_nob erts_atomic32_inc_read_nob
-#define erts_smp_atomic32_dec_read_nob erts_atomic32_dec_read_nob
-#define erts_smp_atomic32_inc_nob erts_atomic32_inc_nob
-#define erts_smp_atomic32_dec_nob erts_atomic32_dec_nob
-#define erts_smp_atomic32_add_read_nob erts_atomic32_add_read_nob
-#define erts_smp_atomic32_add_nob erts_atomic32_add_nob
-#define erts_smp_atomic32_read_bor_nob erts_atomic32_read_bor_nob
-#define erts_smp_atomic32_read_band_nob erts_atomic32_read_band_nob
-#define erts_smp_atomic32_xchg_nob erts_atomic32_xchg_nob
-#define erts_smp_atomic32_cmpxchg_nob erts_atomic32_cmpxchg_nob
-#define erts_smp_atomic32_read_bset_nob erts_atomic32_read_bset_nob
-
-#define erts_smp_atomic32_init_mb erts_atomic32_init_mb
-#define erts_smp_atomic32_set_mb erts_atomic32_set_mb
-#define erts_smp_atomic32_read_mb erts_atomic32_read_mb
-#define erts_smp_atomic32_inc_read_mb erts_atomic32_inc_read_mb
-#define erts_smp_atomic32_dec_read_mb erts_atomic32_dec_read_mb
-#define erts_smp_atomic32_inc_mb erts_atomic32_inc_mb
-#define erts_smp_atomic32_dec_mb erts_atomic32_dec_mb
-#define erts_smp_atomic32_add_read_mb erts_atomic32_add_read_mb
-#define erts_smp_atomic32_add_mb erts_atomic32_add_mb
-#define erts_smp_atomic32_read_bor_mb erts_atomic32_read_bor_mb
-#define erts_smp_atomic32_read_band_mb erts_atomic32_read_band_mb
-#define erts_smp_atomic32_xchg_mb erts_atomic32_xchg_mb
-#define erts_smp_atomic32_cmpxchg_mb erts_atomic32_cmpxchg_mb
-#define erts_smp_atomic32_read_bset_mb erts_atomic32_read_bset_mb
-
-#define erts_smp_atomic32_init_acqb erts_atomic32_init_acqb
-#define erts_smp_atomic32_set_acqb erts_atomic32_set_acqb
-#define erts_smp_atomic32_read_acqb erts_atomic32_read_acqb
-#define erts_smp_atomic32_inc_read_acqb erts_atomic32_inc_read_acqb
-#define erts_smp_atomic32_dec_read_acqb erts_atomic32_dec_read_acqb
-#define erts_smp_atomic32_inc_acqb erts_atomic32_inc_acqb
-#define erts_smp_atomic32_dec_acqb erts_atomic32_dec_acqb
-#define erts_smp_atomic32_add_read_acqb erts_atomic32_add_read_acqb
-#define erts_smp_atomic32_add_acqb erts_atomic32_add_acqb
-#define erts_smp_atomic32_read_bor_acqb erts_atomic32_read_bor_acqb
-#define erts_smp_atomic32_read_band_acqb erts_atomic32_read_band_acqb
-#define erts_smp_atomic32_xchg_acqb erts_atomic32_xchg_acqb
-#define erts_smp_atomic32_cmpxchg_acqb erts_atomic32_cmpxchg_acqb
-#define erts_smp_atomic32_read_bset_acqb erts_atomic32_read_bset_acqb
-
-#define erts_smp_atomic32_init_relb erts_atomic32_init_relb
-#define erts_smp_atomic32_set_relb erts_atomic32_set_relb
-#define erts_smp_atomic32_read_relb erts_atomic32_read_relb
-#define erts_smp_atomic32_inc_read_relb erts_atomic32_inc_read_relb
-#define erts_smp_atomic32_dec_read_relb erts_atomic32_dec_read_relb
-#define erts_smp_atomic32_inc_relb erts_atomic32_inc_relb
-#define erts_smp_atomic32_dec_relb erts_atomic32_dec_relb
-#define erts_smp_atomic32_add_read_relb erts_atomic32_add_read_relb
-#define erts_smp_atomic32_add_relb erts_atomic32_add_relb
-#define erts_smp_atomic32_read_bor_relb erts_atomic32_read_bor_relb
-#define erts_smp_atomic32_read_band_relb erts_atomic32_read_band_relb
-#define erts_smp_atomic32_xchg_relb erts_atomic32_xchg_relb
-#define erts_smp_atomic32_cmpxchg_relb erts_atomic32_cmpxchg_relb
-#define erts_smp_atomic32_read_bset_relb erts_atomic32_read_bset_relb
-
-#define erts_smp_atomic32_init_ddrb erts_atomic32_init_ddrb
-#define erts_smp_atomic32_set_ddrb erts_atomic32_set_ddrb
-#define erts_smp_atomic32_read_ddrb erts_atomic32_read_ddrb
-#define erts_smp_atomic32_inc_read_ddrb erts_atomic32_inc_read_ddrb
-#define erts_smp_atomic32_dec_read_ddrb erts_atomic32_dec_read_ddrb
-#define erts_smp_atomic32_inc_ddrb erts_atomic32_inc_ddrb
-#define erts_smp_atomic32_dec_ddrb erts_atomic32_dec_ddrb
-#define erts_smp_atomic32_add_read_ddrb erts_atomic32_add_read_ddrb
-#define erts_smp_atomic32_add_ddrb erts_atomic32_add_ddrb
-#define erts_smp_atomic32_read_bor_ddrb erts_atomic32_read_bor_ddrb
-#define erts_smp_atomic32_read_band_ddrb erts_atomic32_read_band_ddrb
-#define erts_smp_atomic32_xchg_ddrb erts_atomic32_xchg_ddrb
-#define erts_smp_atomic32_cmpxchg_ddrb erts_atomic32_cmpxchg_ddrb
-#define erts_smp_atomic32_read_bset_ddrb erts_atomic32_read_bset_ddrb
-
-#define erts_smp_atomic32_init_rb erts_atomic32_init_rb
-#define erts_smp_atomic32_set_rb erts_atomic32_set_rb
-#define erts_smp_atomic32_read_rb erts_atomic32_read_rb
-#define erts_smp_atomic32_inc_read_rb erts_atomic32_inc_read_rb
-#define erts_smp_atomic32_dec_read_rb erts_atomic32_dec_read_rb
-#define erts_smp_atomic32_inc_rb erts_atomic32_inc_rb
-#define erts_smp_atomic32_dec_rb erts_atomic32_dec_rb
-#define erts_smp_atomic32_add_read_rb erts_atomic32_add_read_rb
-#define erts_smp_atomic32_add_rb erts_atomic32_add_rb
-#define erts_smp_atomic32_read_bor_rb erts_atomic32_read_bor_rb
-#define erts_smp_atomic32_read_band_rb erts_atomic32_read_band_rb
-#define erts_smp_atomic32_xchg_rb erts_atomic32_xchg_rb
-#define erts_smp_atomic32_cmpxchg_rb erts_atomic32_cmpxchg_rb
-#define erts_smp_atomic32_read_bset_rb erts_atomic32_read_bset_rb
-
-#define erts_smp_atomic32_init_wb erts_atomic32_init_wb
-#define erts_smp_atomic32_set_wb erts_atomic32_set_wb
-#define erts_smp_atomic32_read_wb erts_atomic32_read_wb
-#define erts_smp_atomic32_inc_read_wb erts_atomic32_inc_read_wb
-#define erts_smp_atomic32_dec_read_wb erts_atomic32_dec_read_wb
-#define erts_smp_atomic32_inc_wb erts_atomic32_inc_wb
-#define erts_smp_atomic32_dec_wb erts_atomic32_dec_wb
-#define erts_smp_atomic32_add_read_wb erts_atomic32_add_read_wb
-#define erts_smp_atomic32_add_wb erts_atomic32_add_wb
-#define erts_smp_atomic32_read_bor_wb erts_atomic32_read_bor_wb
-#define erts_smp_atomic32_read_band_wb erts_atomic32_read_band_wb
-#define erts_smp_atomic32_xchg_wb erts_atomic32_xchg_wb
-#define erts_smp_atomic32_cmpxchg_wb erts_atomic32_cmpxchg_wb
-#define erts_smp_atomic32_read_bset_wb erts_atomic32_read_bset_wb
-
-#define erts_smp_atomic32_set_dirty erts_atomic32_set_dirty
-#define erts_smp_atomic32_read_dirty erts_atomic32_read_dirty
-
-/* 64-bit atomics */
-
-#define erts_smp_atomic64_init_nob erts_atomic64_init_nob
-#define erts_smp_atomic64_set_nob erts_atomic64_set_nob
-#define erts_smp_atomic64_read_nob erts_atomic64_read_nob
-#define erts_smp_atomic64_inc_read_nob erts_atomic64_inc_read_nob
-#define erts_smp_atomic64_dec_read_nob erts_atomic64_dec_read_nob
-#define erts_smp_atomic64_inc_nob erts_atomic64_inc_nob
-#define erts_smp_atomic64_dec_nob erts_atomic64_dec_nob
-#define erts_smp_atomic64_add_read_nob erts_atomic64_add_read_nob
-#define erts_smp_atomic64_add_nob erts_atomic64_add_nob
-#define erts_smp_atomic64_read_bor_nob erts_atomic64_read_bor_nob
-#define erts_smp_atomic64_read_band_nob erts_atomic64_read_band_nob
-#define erts_smp_atomic64_xchg_nob erts_atomic64_xchg_nob
-#define erts_smp_atomic64_cmpxchg_nob erts_atomic64_cmpxchg_nob
-#define erts_smp_atomic64_read_bset_nob erts_atomic64_read_bset_nob
-
-#define erts_smp_atomic64_init_mb erts_atomic64_init_mb
-#define erts_smp_atomic64_set_mb erts_atomic64_set_mb
-#define erts_smp_atomic64_read_mb erts_atomic64_read_mb
-#define erts_smp_atomic64_inc_read_mb erts_atomic64_inc_read_mb
-#define erts_smp_atomic64_dec_read_mb erts_atomic64_dec_read_mb
-#define erts_smp_atomic64_inc_mb erts_atomic64_inc_mb
-#define erts_smp_atomic64_dec_mb erts_atomic64_dec_mb
-#define erts_smp_atomic64_add_read_mb erts_atomic64_add_read_mb
-#define erts_smp_atomic64_add_mb erts_atomic64_add_mb
-#define erts_smp_atomic64_read_bor_mb erts_atomic64_read_bor_mb
-#define erts_smp_atomic64_read_band_mb erts_atomic64_read_band_mb
-#define erts_smp_atomic64_xchg_mb erts_atomic64_xchg_mb
-#define erts_smp_atomic64_cmpxchg_mb erts_atomic64_cmpxchg_mb
-#define erts_smp_atomic64_read_bset_mb erts_atomic64_read_bset_mb
-
-#define erts_smp_atomic64_init_acqb erts_atomic64_init_acqb
-#define erts_smp_atomic64_set_acqb erts_atomic64_set_acqb
-#define erts_smp_atomic64_read_acqb erts_atomic64_read_acqb
-#define erts_smp_atomic64_inc_read_acqb erts_atomic64_inc_read_acqb
-#define erts_smp_atomic64_dec_read_acqb erts_atomic64_dec_read_acqb
-#define erts_smp_atomic64_inc_acqb erts_atomic64_inc_acqb
-#define erts_smp_atomic64_dec_acqb erts_atomic64_dec_acqb
-#define erts_smp_atomic64_add_read_acqb erts_atomic64_add_read_acqb
-#define erts_smp_atomic64_add_acqb erts_atomic64_add_acqb
-#define erts_smp_atomic64_read_bor_acqb erts_atomic64_read_bor_acqb
-#define erts_smp_atomic64_read_band_acqb erts_atomic64_read_band_acqb
-#define erts_smp_atomic64_xchg_acqb erts_atomic64_xchg_acqb
-#define erts_smp_atomic64_cmpxchg_acqb erts_atomic64_cmpxchg_acqb
-#define erts_smp_atomic64_read_bset_acqb erts_atomic64_read_bset_acqb
-
-#define erts_smp_atomic64_init_relb erts_atomic64_init_relb
-#define erts_smp_atomic64_set_relb erts_atomic64_set_relb
-#define erts_smp_atomic64_read_relb erts_atomic64_read_relb
-#define erts_smp_atomic64_inc_read_relb erts_atomic64_inc_read_relb
-#define erts_smp_atomic64_dec_read_relb erts_atomic64_dec_read_relb
-#define erts_smp_atomic64_inc_relb erts_atomic64_inc_relb
-#define erts_smp_atomic64_dec_relb erts_atomic64_dec_relb
-#define erts_smp_atomic64_add_read_relb erts_atomic64_add_read_relb
-#define erts_smp_atomic64_add_relb erts_atomic64_add_relb
-#define erts_smp_atomic64_read_bor_relb erts_atomic64_read_bor_relb
-#define erts_smp_atomic64_read_band_relb erts_atomic64_read_band_relb
-#define erts_smp_atomic64_xchg_relb erts_atomic64_xchg_relb
-#define erts_smp_atomic64_cmpxchg_relb erts_atomic64_cmpxchg_relb
-#define erts_smp_atomic64_read_bset_relb erts_atomic64_read_bset_relb
-
-#define erts_smp_atomic64_init_ddrb erts_atomic64_init_ddrb
-#define erts_smp_atomic64_set_ddrb erts_atomic64_set_ddrb
-#define erts_smp_atomic64_read_ddrb erts_atomic64_read_ddrb
-#define erts_smp_atomic64_inc_read_ddrb erts_atomic64_inc_read_ddrb
-#define erts_smp_atomic64_dec_read_ddrb erts_atomic64_dec_read_ddrb
-#define erts_smp_atomic64_inc_ddrb erts_atomic64_inc_ddrb
-#define erts_smp_atomic64_dec_ddrb erts_atomic64_dec_ddrb
-#define erts_smp_atomic64_add_read_ddrb erts_atomic64_add_read_ddrb
-#define erts_smp_atomic64_add_ddrb erts_atomic64_add_ddrb
-#define erts_smp_atomic64_read_bor_ddrb erts_atomic64_read_bor_ddrb
-#define erts_smp_atomic64_read_band_ddrb erts_atomic64_read_band_ddrb
-#define erts_smp_atomic64_xchg_ddrb erts_atomic64_xchg_ddrb
-#define erts_smp_atomic64_cmpxchg_ddrb erts_atomic64_cmpxchg_ddrb
-#define erts_smp_atomic64_read_bset_ddrb erts_atomic64_read_bset_ddrb
-
-#define erts_smp_atomic64_init_rb erts_atomic64_init_rb
-#define erts_smp_atomic64_set_rb erts_atomic64_set_rb
-#define erts_smp_atomic64_read_rb erts_atomic64_read_rb
-#define erts_smp_atomic64_inc_read_rb erts_atomic64_inc_read_rb
-#define erts_smp_atomic64_dec_read_rb erts_atomic64_dec_read_rb
-#define erts_smp_atomic64_inc_rb erts_atomic64_inc_rb
-#define erts_smp_atomic64_dec_rb erts_atomic64_dec_rb
-#define erts_smp_atomic64_add_read_rb erts_atomic64_add_read_rb
-#define erts_smp_atomic64_add_rb erts_atomic64_add_rb
-#define erts_smp_atomic64_read_bor_rb erts_atomic64_read_bor_rb
-#define erts_smp_atomic64_read_band_rb erts_atomic64_read_band_rb
-#define erts_smp_atomic64_xchg_rb erts_atomic64_xchg_rb
-#define erts_smp_atomic64_cmpxchg_rb erts_atomic64_cmpxchg_rb
-#define erts_smp_atomic64_read_bset_rb erts_atomic64_read_bset_rb
-
-#define erts_smp_atomic64_init_wb erts_atomic64_init_wb
-#define erts_smp_atomic64_set_wb erts_atomic64_set_wb
-#define erts_smp_atomic64_read_wb erts_atomic64_read_wb
-#define erts_smp_atomic64_inc_read_wb erts_atomic64_inc_read_wb
-#define erts_smp_atomic64_dec_read_wb erts_atomic64_dec_read_wb
-#define erts_smp_atomic64_inc_wb erts_atomic64_inc_wb
-#define erts_smp_atomic64_dec_wb erts_atomic64_dec_wb
-#define erts_smp_atomic64_add_read_wb erts_atomic64_add_read_wb
-#define erts_smp_atomic64_add_wb erts_atomic64_add_wb
-#define erts_smp_atomic64_read_bor_wb erts_atomic64_read_bor_wb
-#define erts_smp_atomic64_read_band_wb erts_atomic64_read_band_wb
-#define erts_smp_atomic64_xchg_wb erts_atomic64_xchg_wb
-#define erts_smp_atomic64_cmpxchg_wb erts_atomic64_cmpxchg_wb
-#define erts_smp_atomic64_read_bset_wb erts_atomic64_read_bset_wb
-
-#define erts_smp_atomic64_set_dirty erts_atomic64_set_dirty
-#define erts_smp_atomic64_read_dirty erts_atomic64_read_dirty
-
-#else /* !ERTS_SMP */
-
-/* Double word size atomics */
-
-#define erts_smp_dw_atomic_init_nob erts_no_dw_atomic_set
-#define erts_smp_dw_atomic_set_nob erts_no_dw_atomic_set
-#define erts_smp_dw_atomic_read_nob erts_no_dw_atomic_read
-#define erts_smp_dw_atomic_cmpxchg_nob erts_no_dw_atomic_cmpxchg
-
-#define erts_smp_dw_atomic_init_mb erts_no_dw_atomic_init
-#define erts_smp_dw_atomic_set_mb erts_no_dw_atomic_set
-#define erts_smp_dw_atomic_read_mb erts_no_dw_atomic_read
-#define erts_smp_dw_atomic_cmpxchg_mb erts_no_dw_atomic_cmpxchg
-
-#define erts_smp_dw_atomic_init_acqb erts_no_dw_atomic_init
-#define erts_smp_dw_atomic_set_acqb erts_no_dw_atomic_set
-#define erts_smp_dw_atomic_read_acqb erts_no_dw_atomic_read
-#define erts_smp_dw_atomic_cmpxchg_acqb erts_no_dw_atomic_cmpxchg
-
-#define erts_smp_dw_atomic_init_relb erts_no_dw_atomic_init
-#define erts_smp_dw_atomic_set_relb erts_no_dw_atomic_set
-#define erts_smp_dw_atomic_read_relb erts_no_dw_atomic_read
-#define erts_smp_dw_atomic_cmpxchg_relb erts_no_dw_atomic_cmpxchg
-
-#define erts_smp_dw_atomic_init_ddrb erts_no_dw_atomic_init
-#define erts_smp_dw_atomic_set_ddrb erts_no_dw_atomic_set
-#define erts_smp_dw_atomic_read_ddrb erts_no_dw_atomic_read
-#define erts_smp_dw_atomic_cmpxchg_ddrb erts_no_dw_atomic_cmpxchg
-
-#define erts_smp_dw_atomic_init_rb erts_no_dw_atomic_init
-#define erts_smp_dw_atomic_set_rb erts_no_dw_atomic_set
-#define erts_smp_dw_atomic_read_rb erts_no_dw_atomic_read
-#define erts_smp_dw_atomic_cmpxchg_rb erts_no_dw_atomic_cmpxchg
-
-#define erts_smp_dw_atomic_init_wb erts_no_dw_atomic_init
-#define erts_smp_dw_atomic_set_wb erts_no_dw_atomic_set
-#define erts_smp_dw_atomic_read_wb erts_no_dw_atomic_read
-#define erts_smp_dw_atomic_cmpxchg_wb erts_no_dw_atomic_cmpxchg
-
-#define erts_smp_dw_atomic_set_dirty erts_no_dw_atomic_set
-#define erts_smp_dw_atomic_read_dirty erts_no_dw_atomic_read
-
-/* Word size atomics */
-
-#define erts_smp_atomic_init_nob erts_no_atomic_set
-#define erts_smp_atomic_set_nob erts_no_atomic_set
-#define erts_smp_atomic_read_nob erts_no_atomic_read
-#define erts_smp_atomic_inc_read_nob erts_no_atomic_inc_read
-#define erts_smp_atomic_dec_read_nob erts_no_atomic_dec_read
-#define erts_smp_atomic_inc_nob erts_no_atomic_inc
-#define erts_smp_atomic_dec_nob erts_no_atomic_dec
-#define erts_smp_atomic_add_read_nob erts_no_atomic_add_read
-#define erts_smp_atomic_add_nob erts_no_atomic_add
-#define erts_smp_atomic_read_bor_nob erts_no_atomic_read_bor
-#define erts_smp_atomic_read_band_nob erts_no_atomic_read_band
-#define erts_smp_atomic_xchg_nob erts_no_atomic_xchg
-#define erts_smp_atomic_cmpxchg_nob erts_no_atomic_cmpxchg
-#define erts_smp_atomic_read_bset_nob erts_no_atomic_read_bset
-
-#define erts_smp_atomic_init_mb erts_no_atomic_set
-#define erts_smp_atomic_set_mb erts_no_atomic_set
-#define erts_smp_atomic_read_mb erts_no_atomic_read
-#define erts_smp_atomic_inc_read_mb erts_no_atomic_inc_read
-#define erts_smp_atomic_dec_read_mb erts_no_atomic_dec_read
-#define erts_smp_atomic_inc_mb erts_no_atomic_inc
-#define erts_smp_atomic_dec_mb erts_no_atomic_dec
-#define erts_smp_atomic_add_read_mb erts_no_atomic_add_read
-#define erts_smp_atomic_add_mb erts_no_atomic_add
-#define erts_smp_atomic_read_bor_mb erts_no_atomic_read_bor
-#define erts_smp_atomic_read_band_mb erts_no_atomic_read_band
-#define erts_smp_atomic_xchg_mb erts_no_atomic_xchg
-#define erts_smp_atomic_cmpxchg_mb erts_no_atomic_cmpxchg
-#define erts_smp_atomic_read_bset_mb erts_no_atomic_read_bset
-
-#define erts_smp_atomic_init_acqb erts_no_atomic_set
-#define erts_smp_atomic_set_acqb erts_no_atomic_set
-#define erts_smp_atomic_read_acqb erts_no_atomic_read
-#define erts_smp_atomic_inc_read_acqb erts_no_atomic_inc_read
-#define erts_smp_atomic_dec_read_acqb erts_no_atomic_dec_read
-#define erts_smp_atomic_inc_acqb erts_no_atomic_inc
-#define erts_smp_atomic_dec_acqb erts_no_atomic_dec
-#define erts_smp_atomic_add_read_acqb erts_no_atomic_add_read
-#define erts_smp_atomic_add_acqb erts_no_atomic_add
-#define erts_smp_atomic_read_bor_acqb erts_no_atomic_read_bor
-#define erts_smp_atomic_read_band_acqb erts_no_atomic_read_band
-#define erts_smp_atomic_xchg_acqb erts_no_atomic_xchg
-#define erts_smp_atomic_cmpxchg_acqb erts_no_atomic_cmpxchg
-#define erts_smp_atomic_read_bset_acqb erts_no_atomic_read_bset
-
-#define erts_smp_atomic_init_relb erts_no_atomic_set
-#define erts_smp_atomic_set_relb erts_no_atomic_set
-#define erts_smp_atomic_read_relb erts_no_atomic_read
-#define erts_smp_atomic_inc_read_relb erts_no_atomic_inc_read
-#define erts_smp_atomic_dec_read_relb erts_no_atomic_dec_read
-#define erts_smp_atomic_inc_relb erts_no_atomic_inc
-#define erts_smp_atomic_dec_relb erts_no_atomic_dec
-#define erts_smp_atomic_add_read_relb erts_no_atomic_add_read
-#define erts_smp_atomic_add_relb erts_no_atomic_add
-#define erts_smp_atomic_read_bor_relb erts_no_atomic_read_bor
-#define erts_smp_atomic_read_band_relb erts_no_atomic_read_band
-#define erts_smp_atomic_xchg_relb erts_no_atomic_xchg
-#define erts_smp_atomic_cmpxchg_relb erts_no_atomic_cmpxchg
-#define erts_smp_atomic_read_bset_relb erts_no_atomic_read_bset
-
-#define erts_smp_atomic_init_ddrb erts_no_atomic_set
-#define erts_smp_atomic_set_ddrb erts_no_atomic_set
-#define erts_smp_atomic_read_ddrb erts_no_atomic_read
-#define erts_smp_atomic_inc_read_ddrb erts_no_atomic_inc_read
-#define erts_smp_atomic_dec_read_ddrb erts_no_atomic_dec_read
-#define erts_smp_atomic_inc_ddrb erts_no_atomic_inc
-#define erts_smp_atomic_dec_ddrb erts_no_atomic_dec
-#define erts_smp_atomic_add_read_ddrb erts_no_atomic_add_read
-#define erts_smp_atomic_add_ddrb erts_no_atomic_add
-#define erts_smp_atomic_read_bor_ddrb erts_no_atomic_read_bor
-#define erts_smp_atomic_read_band_ddrb erts_no_atomic_read_band
-#define erts_smp_atomic_xchg_ddrb erts_no_atomic_xchg
-#define erts_smp_atomic_cmpxchg_ddrb erts_no_atomic_cmpxchg
-#define erts_smp_atomic_read_bset_ddrb erts_no_atomic_read_bset
-
-#define erts_smp_atomic_init_rb erts_no_atomic_set
-#define erts_smp_atomic_set_rb erts_no_atomic_set
-#define erts_smp_atomic_read_rb erts_no_atomic_read
-#define erts_smp_atomic_inc_read_rb erts_no_atomic_inc_read
-#define erts_smp_atomic_dec_read_rb erts_no_atomic_dec_read
-#define erts_smp_atomic_inc_rb erts_no_atomic_inc
-#define erts_smp_atomic_dec_rb erts_no_atomic_dec
-#define erts_smp_atomic_add_read_rb erts_no_atomic_add_read
-#define erts_smp_atomic_add_rb erts_no_atomic_add
-#define erts_smp_atomic_read_bor_rb erts_no_atomic_read_bor
-#define erts_smp_atomic_read_band_rb erts_no_atomic_read_band
-#define erts_smp_atomic_xchg_rb erts_no_atomic_xchg
-#define erts_smp_atomic_cmpxchg_rb erts_no_atomic_cmpxchg
-#define erts_smp_atomic_read_bset_rb erts_no_atomic_read_bset
-
-#define erts_smp_atomic_init_wb erts_no_atomic_set
-#define erts_smp_atomic_set_wb erts_no_atomic_set
-#define erts_smp_atomic_read_wb erts_no_atomic_read
-#define erts_smp_atomic_inc_read_wb erts_no_atomic_inc_read
-#define erts_smp_atomic_dec_read_wb erts_no_atomic_dec_read
-#define erts_smp_atomic_inc_wb erts_no_atomic_inc
-#define erts_smp_atomic_dec_wb erts_no_atomic_dec
-#define erts_smp_atomic_add_read_wb erts_no_atomic_add_read
-#define erts_smp_atomic_add_wb erts_no_atomic_add
-#define erts_smp_atomic_read_bor_wb erts_no_atomic_read_bor
-#define erts_smp_atomic_read_band_wb erts_no_atomic_read_band
-#define erts_smp_atomic_xchg_wb erts_no_atomic_xchg
-#define erts_smp_atomic_cmpxchg_wb erts_no_atomic_cmpxchg
-#define erts_smp_atomic_read_bset_wb erts_no_atomic_read_bset
-
-#define erts_smp_atomic_set_dirty erts_no_atomic_set
-#define erts_smp_atomic_read_dirty erts_no_atomic_read
-
-/* 32-bit atomics */
-
-#define erts_smp_atomic32_init_nob erts_no_atomic32_set
-#define erts_smp_atomic32_set_nob erts_no_atomic32_set
-#define erts_smp_atomic32_read_nob erts_no_atomic32_read
-#define erts_smp_atomic32_inc_read_nob erts_no_atomic32_inc_read
-#define erts_smp_atomic32_dec_read_nob erts_no_atomic32_dec_read
-#define erts_smp_atomic32_inc_nob erts_no_atomic32_inc
-#define erts_smp_atomic32_dec_nob erts_no_atomic32_dec
-#define erts_smp_atomic32_add_read_nob erts_no_atomic32_add_read
-#define erts_smp_atomic32_add_nob erts_no_atomic32_add
-#define erts_smp_atomic32_read_bor_nob erts_no_atomic32_read_bor
-#define erts_smp_atomic32_read_band_nob erts_no_atomic32_read_band
-#define erts_smp_atomic32_xchg_nob erts_no_atomic32_xchg
-#define erts_smp_atomic32_cmpxchg_nob erts_no_atomic32_cmpxchg
-#define erts_smp_atomic32_read_bset_nob erts_no_atomic32_read_bset
-
-#define erts_smp_atomic32_init_mb erts_no_atomic32_set
-#define erts_smp_atomic32_set_mb erts_no_atomic32_set
-#define erts_smp_atomic32_read_mb erts_no_atomic32_read
-#define erts_smp_atomic32_inc_read_mb erts_no_atomic32_inc_read
-#define erts_smp_atomic32_dec_read_mb erts_no_atomic32_dec_read
-#define erts_smp_atomic32_inc_mb erts_no_atomic32_inc
-#define erts_smp_atomic32_dec_mb erts_no_atomic32_dec
-#define erts_smp_atomic32_add_read_mb erts_no_atomic32_add_read
-#define erts_smp_atomic32_add_mb erts_no_atomic32_add
-#define erts_smp_atomic32_read_bor_mb erts_no_atomic32_read_bor
-#define erts_smp_atomic32_read_band_mb erts_no_atomic32_read_band
-#define erts_smp_atomic32_xchg_mb erts_no_atomic32_xchg
-#define erts_smp_atomic32_cmpxchg_mb erts_no_atomic32_cmpxchg
-#define erts_smp_atomic32_read_bset_mb erts_no_atomic32_read_bset
-
-#define erts_smp_atomic32_init_acqb erts_no_atomic32_set
-#define erts_smp_atomic32_set_acqb erts_no_atomic32_set
-#define erts_smp_atomic32_read_acqb erts_no_atomic32_read
-#define erts_smp_atomic32_inc_read_acqb erts_no_atomic32_inc_read
-#define erts_smp_atomic32_dec_read_acqb erts_no_atomic32_dec_read
-#define erts_smp_atomic32_inc_acqb erts_no_atomic32_inc
-#define erts_smp_atomic32_dec_acqb erts_no_atomic32_dec
-#define erts_smp_atomic32_add_read_acqb erts_no_atomic32_add_read
-#define erts_smp_atomic32_add_acqb erts_no_atomic32_add
-#define erts_smp_atomic32_read_bor_acqb erts_no_atomic32_read_bor
-#define erts_smp_atomic32_read_band_acqb erts_no_atomic32_read_band
-#define erts_smp_atomic32_xchg_acqb erts_no_atomic32_xchg
-#define erts_smp_atomic32_cmpxchg_acqb erts_no_atomic32_cmpxchg
-#define erts_smp_atomic32_read_bset_acqb erts_no_atomic32_read_bset
-
-#define erts_smp_atomic32_init_relb erts_no_atomic32_set
-#define erts_smp_atomic32_set_relb erts_no_atomic32_set
-#define erts_smp_atomic32_read_relb erts_no_atomic32_read
-#define erts_smp_atomic32_inc_read_relb erts_no_atomic32_inc_read
-#define erts_smp_atomic32_dec_read_relb erts_no_atomic32_dec_read
-#define erts_smp_atomic32_inc_relb erts_no_atomic32_inc
-#define erts_smp_atomic32_dec_relb erts_no_atomic32_dec
-#define erts_smp_atomic32_add_read_relb erts_no_atomic32_add_read
-#define erts_smp_atomic32_add_relb erts_no_atomic32_add
-#define erts_smp_atomic32_read_bor_relb erts_no_atomic32_read_bor
-#define erts_smp_atomic32_read_band_relb erts_no_atomic32_read_band
-#define erts_smp_atomic32_xchg_relb erts_no_atomic32_xchg
-#define erts_smp_atomic32_cmpxchg_relb erts_no_atomic32_cmpxchg
-#define erts_smp_atomic32_read_bset_relb erts_no_atomic32_read_bset
-
-#define erts_smp_atomic32_init_ddrb erts_no_atomic32_set
-#define erts_smp_atomic32_set_ddrb erts_no_atomic32_set
-#define erts_smp_atomic32_read_ddrb erts_no_atomic32_read
-#define erts_smp_atomic32_inc_read_ddrb erts_no_atomic32_inc_read
-#define erts_smp_atomic32_dec_read_ddrb erts_no_atomic32_dec_read
-#define erts_smp_atomic32_inc_ddrb erts_no_atomic32_inc
-#define erts_smp_atomic32_dec_ddrb erts_no_atomic32_dec
-#define erts_smp_atomic32_add_read_ddrb erts_no_atomic32_add_read
-#define erts_smp_atomic32_add_ddrb erts_no_atomic32_add
-#define erts_smp_atomic32_read_bor_ddrb erts_no_atomic32_read_bor
-#define erts_smp_atomic32_read_band_ddrb erts_no_atomic32_read_band
-#define erts_smp_atomic32_xchg_ddrb erts_no_atomic32_xchg
-#define erts_smp_atomic32_cmpxchg_ddrb erts_no_atomic32_cmpxchg
-#define erts_smp_atomic32_read_bset_ddrb erts_no_atomic32_read_bset
-
-#define erts_smp_atomic32_init_rb erts_no_atomic32_set
-#define erts_smp_atomic32_set_rb erts_no_atomic32_set
-#define erts_smp_atomic32_read_rb erts_no_atomic32_read
-#define erts_smp_atomic32_inc_read_rb erts_no_atomic32_inc_read
-#define erts_smp_atomic32_dec_read_rb erts_no_atomic32_dec_read
-#define erts_smp_atomic32_inc_rb erts_no_atomic32_inc
-#define erts_smp_atomic32_dec_rb erts_no_atomic32_dec
-#define erts_smp_atomic32_add_read_rb erts_no_atomic32_add_read
-#define erts_smp_atomic32_add_rb erts_no_atomic32_add
-#define erts_smp_atomic32_read_bor_rb erts_no_atomic32_read_bor
-#define erts_smp_atomic32_read_band_rb erts_no_atomic32_read_band
-#define erts_smp_atomic32_xchg_rb erts_no_atomic32_xchg
-#define erts_smp_atomic32_cmpxchg_rb erts_no_atomic32_cmpxchg
-#define erts_smp_atomic32_read_bset_rb erts_no_atomic32_read_bset
-
-#define erts_smp_atomic32_init_wb erts_no_atomic32_set
-#define erts_smp_atomic32_set_wb erts_no_atomic32_set
-#define erts_smp_atomic32_read_wb erts_no_atomic32_read
-#define erts_smp_atomic32_inc_read_wb erts_no_atomic32_inc_read
-#define erts_smp_atomic32_dec_read_wb erts_no_atomic32_dec_read
-#define erts_smp_atomic32_inc_wb erts_no_atomic32_inc
-#define erts_smp_atomic32_dec_wb erts_no_atomic32_dec
-#define erts_smp_atomic32_add_read_wb erts_no_atomic32_add_read
-#define erts_smp_atomic32_add_wb erts_no_atomic32_add
-#define erts_smp_atomic32_read_bor_wb erts_no_atomic32_read_bor
-#define erts_smp_atomic32_read_band_wb erts_no_atomic32_read_band
-#define erts_smp_atomic32_xchg_wb erts_no_atomic32_xchg
-#define erts_smp_atomic32_cmpxchg_wb erts_no_atomic32_cmpxchg
-#define erts_smp_atomic32_read_bset_wb erts_no_atomic32_read_bset
-
-#define erts_smp_atomic32_set_dirty erts_no_atomic32_set
-#define erts_smp_atomic32_read_dirty erts_no_atomic32_read
-
-/* 64-bit atomics */
-
-#define erts_smp_atomic64_init_nob erts_no_atomic64_set
-#define erts_smp_atomic64_set_nob erts_no_atomic64_set
-#define erts_smp_atomic64_read_nob erts_no_atomic64_read
-#define erts_smp_atomic64_inc_read_nob erts_no_atomic64_inc_read
-#define erts_smp_atomic64_dec_read_nob erts_no_atomic64_dec_read
-#define erts_smp_atomic64_inc_nob erts_no_atomic64_inc
-#define erts_smp_atomic64_dec_nob erts_no_atomic64_dec
-#define erts_smp_atomic64_add_read_nob erts_no_atomic64_add_read
-#define erts_smp_atomic64_add_nob erts_no_atomic64_add
-#define erts_smp_atomic64_read_bor_nob erts_no_atomic64_read_bor
-#define erts_smp_atomic64_read_band_nob erts_no_atomic64_read_band
-#define erts_smp_atomic64_xchg_nob erts_no_atomic64_xchg
-#define erts_smp_atomic64_cmpxchg_nob erts_no_atomic64_cmpxchg
-#define erts_smp_atomic64_read_bset_nob erts_no_atomic64_read_bset
-
-#define erts_smp_atomic64_init_mb erts_no_atomic64_set
-#define erts_smp_atomic64_set_mb erts_no_atomic64_set
-#define erts_smp_atomic64_read_mb erts_no_atomic64_read
-#define erts_smp_atomic64_inc_read_mb erts_no_atomic64_inc_read
-#define erts_smp_atomic64_dec_read_mb erts_no_atomic64_dec_read
-#define erts_smp_atomic64_inc_mb erts_no_atomic64_inc
-#define erts_smp_atomic64_dec_mb erts_no_atomic64_dec
-#define erts_smp_atomic64_add_read_mb erts_no_atomic64_add_read
-#define erts_smp_atomic64_add_mb erts_no_atomic64_add
-#define erts_smp_atomic64_read_bor_mb erts_no_atomic64_read_bor
-#define erts_smp_atomic64_read_band_mb erts_no_atomic64_read_band
-#define erts_smp_atomic64_xchg_mb erts_no_atomic64_xchg
-#define erts_smp_atomic64_cmpxchg_mb erts_no_atomic64_cmpxchg
-#define erts_smp_atomic64_read_bset_mb erts_no_atomic64_read_bset
-
-#define erts_smp_atomic64_init_acqb erts_no_atomic64_set
-#define erts_smp_atomic64_set_acqb erts_no_atomic64_set
-#define erts_smp_atomic64_read_acqb erts_no_atomic64_read
-#define erts_smp_atomic64_inc_read_acqb erts_no_atomic64_inc_read
-#define erts_smp_atomic64_dec_read_acqb erts_no_atomic64_dec_read
-#define erts_smp_atomic64_inc_acqb erts_no_atomic64_inc
-#define erts_smp_atomic64_dec_acqb erts_no_atomic64_dec
-#define erts_smp_atomic64_add_read_acqb erts_no_atomic64_add_read
-#define erts_smp_atomic64_add_acqb erts_no_atomic64_add
-#define erts_smp_atomic64_read_bor_acqb erts_no_atomic64_read_bor
-#define erts_smp_atomic64_read_band_acqb erts_no_atomic64_read_band
-#define erts_smp_atomic64_xchg_acqb erts_no_atomic64_xchg
-#define erts_smp_atomic64_cmpxchg_acqb erts_no_atomic64_cmpxchg
-#define erts_smp_atomic64_read_bset_acqb erts_no_atomic64_read_bset
-
-#define erts_smp_atomic64_init_relb erts_no_atomic64_set
-#define erts_smp_atomic64_set_relb erts_no_atomic64_set
-#define erts_smp_atomic64_read_relb erts_no_atomic64_read
-#define erts_smp_atomic64_inc_read_relb erts_no_atomic64_inc_read
-#define erts_smp_atomic64_dec_read_relb erts_no_atomic64_dec_read
-#define erts_smp_atomic64_inc_relb erts_no_atomic64_inc
-#define erts_smp_atomic64_dec_relb erts_no_atomic64_dec
-#define erts_smp_atomic64_add_read_relb erts_no_atomic64_add_read
-#define erts_smp_atomic64_add_relb erts_no_atomic64_add
-#define erts_smp_atomic64_read_bor_relb erts_no_atomic64_read_bor
-#define erts_smp_atomic64_read_band_relb erts_no_atomic64_read_band
-#define erts_smp_atomic64_xchg_relb erts_no_atomic64_xchg
-#define erts_smp_atomic64_cmpxchg_relb erts_no_atomic64_cmpxchg
-#define erts_smp_atomic64_read_bset_relb erts_no_atomic64_read_bset
-
-#define erts_smp_atomic64_init_ddrb erts_no_atomic64_set
-#define erts_smp_atomic64_set_ddrb erts_no_atomic64_set
-#define erts_smp_atomic64_read_ddrb erts_no_atomic64_read
-#define erts_smp_atomic64_inc_read_ddrb erts_no_atomic64_inc_read
-#define erts_smp_atomic64_dec_read_ddrb erts_no_atomic64_dec_read
-#define erts_smp_atomic64_inc_ddrb erts_no_atomic64_inc
-#define erts_smp_atomic64_dec_ddrb erts_no_atomic64_dec
-#define erts_smp_atomic64_add_read_ddrb erts_no_atomic64_add_read
-#define erts_smp_atomic64_add_ddrb erts_no_atomic64_add
-#define erts_smp_atomic64_read_bor_ddrb erts_no_atomic64_read_bor
-#define erts_smp_atomic64_read_band_ddrb erts_no_atomic64_read_band
-#define erts_smp_atomic64_xchg_ddrb erts_no_atomic64_xchg
-#define erts_smp_atomic64_cmpxchg_ddrb erts_no_atomic64_cmpxchg
-#define erts_smp_atomic64_read_bset_ddrb erts_no_atomic64_read_bset
-
-#define erts_smp_atomic64_init_rb erts_no_atomic64_set
-#define erts_smp_atomic64_set_rb erts_no_atomic64_set
-#define erts_smp_atomic64_read_rb erts_no_atomic64_read
-#define erts_smp_atomic64_inc_read_rb erts_no_atomic64_inc_read
-#define erts_smp_atomic64_dec_read_rb erts_no_atomic64_dec_read
-#define erts_smp_atomic64_inc_rb erts_no_atomic64_inc
-#define erts_smp_atomic64_dec_rb erts_no_atomic64_dec
-#define erts_smp_atomic64_add_read_rb erts_no_atomic64_add_read
-#define erts_smp_atomic64_add_rb erts_no_atomic64_add
-#define erts_smp_atomic64_read_bor_rb erts_no_atomic64_read_bor
-#define erts_smp_atomic64_read_band_rb erts_no_atomic64_read_band
-#define erts_smp_atomic64_xchg_rb erts_no_atomic64_xchg
-#define erts_smp_atomic64_cmpxchg_rb erts_no_atomic64_cmpxchg
-#define erts_smp_atomic64_read_bset_rb erts_no_atomic64_read_bset
-
-#define erts_smp_atomic64_init_wb erts_no_atomic64_set
-#define erts_smp_atomic64_set_wb erts_no_atomic64_set
-#define erts_smp_atomic64_read_wb erts_no_atomic64_read
-#define erts_smp_atomic64_inc_read_wb erts_no_atomic64_inc_read
-#define erts_smp_atomic64_dec_read_wb erts_no_atomic64_dec_read
-#define erts_smp_atomic64_inc_wb erts_no_atomic64_inc
-#define erts_smp_atomic64_dec_wb erts_no_atomic64_dec
-#define erts_smp_atomic64_add_read_wb erts_no_atomic64_add_read
-#define erts_smp_atomic64_add_wb erts_no_atomic64_add
-#define erts_smp_atomic64_read_bor_wb erts_no_atomic64_read_bor
-#define erts_smp_atomic64_read_band_wb erts_no_atomic64_read_band
-#define erts_smp_atomic64_xchg_wb erts_no_atomic64_xchg
-#define erts_smp_atomic64_cmpxchg_wb erts_no_atomic64_cmpxchg
-#define erts_smp_atomic64_read_bset_wb erts_no_atomic64_read_bset
-
-#define erts_smp_atomic64_set_dirty erts_no_atomic64_set
-#define erts_smp_atomic64_read_dirty erts_no_atomic64_read
-
-#endif /* !ERTS_SMP */
-
-#if ERTS_GLB_INLINE_INCL_FUNC_DEF
-
-ERTS_GLB_INLINE void
-erts_smp_thr_init(erts_smp_thr_init_data_t *id)
-{
-#ifdef ERTS_SMP
-    erts_thr_init(id);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_thr_create(erts_smp_tid_t *tid, void * (*func)(void *), void *arg,
-		    erts_smp_thr_opts_t *opts)
-{
-#ifdef ERTS_SMP
-    erts_thr_create(tid, func, arg, opts);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_thr_join(erts_smp_tid_t tid, void **thr_res)
-{
-#ifdef ERTS_SMP
-    erts_thr_join(tid, thr_res);
-#endif
-}
-
-
-ERTS_GLB_INLINE void
-erts_smp_thr_detach(erts_smp_tid_t tid)
-{
-#ifdef ERTS_SMP
-    erts_thr_detach(tid);
-#endif
-}
-
-
-ERTS_GLB_INLINE void
-erts_smp_thr_exit(void *res)
-{
-#ifdef ERTS_SMP
-    erts_thr_exit(res);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_install_exit_handler(void (*exit_handler)(void))
-{
-#ifdef ERTS_SMP
-    erts_thr_install_exit_handler(exit_handler);
-#endif
-}
-
-ERTS_GLB_INLINE erts_smp_tid_t
-erts_smp_thr_self(void)
-{
-#ifdef ERTS_SMP
-    return erts_thr_self();
-#else
-    return 0;
-#endif
-}
-
-
-ERTS_GLB_INLINE int
-erts_smp_equal_tids(erts_smp_tid_t x, erts_smp_tid_t y)
-{
-#ifdef ERTS_SMP
-    return erts_equal_tids(x, y);
-#else
-    return 1;
-#endif
-}
-
-
-#ifdef ERTS_HAVE_REC_MTX_INIT
-ERTS_GLB_INLINE void
-erts_smp_rec_mtx_init(erts_smp_mtx_t *mtx)
-{
-#ifdef ERTS_SMP
-    erts_rec_mtx_init(mtx);
-#endif
-}
-#endif
-
-ERTS_GLB_INLINE void
-erts_smp_mtx_init(erts_smp_mtx_t *mtx, char *name, Eterm extra, erts_lock_flags_t flags)
-{
-#ifdef ERTS_SMP
-    erts_mtx_init(mtx, name, extra, flags);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_mtx_init_locked(erts_smp_mtx_t *mtx, char *name, Eterm extra, erts_lock_flags_t flags)
-{
-#ifdef ERTS_SMP
-    erts_mtx_init_locked(mtx, name, extra, flags);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_mtx_destroy(erts_smp_mtx_t *mtx)
-{
-#ifdef ERTS_SMP
-    erts_mtx_destroy(mtx);
-#endif
-}
-
-ERTS_GLB_INLINE int
-#ifdef ERTS_ENABLE_LOCK_POSITION
-erts_smp_mtx_trylock_x(erts_smp_mtx_t *mtx, char *file, unsigned int line)
-#else
-erts_smp_mtx_trylock(erts_smp_mtx_t *mtx)
-#endif
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_POSITION)
-    return erts_mtx_trylock_x(mtx,file,line);
-#elif defined(ERTS_SMP)
-    return erts_mtx_trylock(mtx);
-#else
-    return 0;
-#endif
-
-}
-
-
-ERTS_GLB_INLINE void
-#ifdef ERTS_ENABLE_LOCK_POSITION
-erts_smp_mtx_lock_x(erts_smp_mtx_t *mtx, char *file, unsigned int line)
-#else
-erts_smp_mtx_lock(erts_smp_mtx_t *mtx)
-#endif
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_POSITION)
-    erts_mtx_lock_x(mtx, file, line);
-#elif defined(ERTS_SMP)
-    erts_mtx_lock(mtx);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_mtx_unlock(erts_smp_mtx_t *mtx)
-{
-#ifdef ERTS_SMP
-    erts_mtx_unlock(mtx);
-#endif
-}
-
-ERTS_GLB_INLINE int
-erts_smp_lc_mtx_is_locked(erts_smp_mtx_t *mtx)
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
-    return erts_lc_mtx_is_locked(mtx);
-#else
-    return 0;
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_cnd_init(erts_smp_cnd_t *cnd)
-{
-#ifdef ERTS_SMP
-    erts_cnd_init(cnd);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_cnd_destroy(erts_smp_cnd_t *cnd)
-{
-#ifdef ERTS_SMP
-    erts_cnd_destroy(cnd);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_cnd_wait(erts_smp_cnd_t *cnd, erts_smp_mtx_t *mtx)
-{
-#ifdef ERTS_SMP
-    erts_cnd_wait(cnd, mtx);
-#endif
-}
-
-/*
- * IMPORTANT note about erts_smp_cnd_signal() and erts_smp_cnd_broadcast()
- *
- * POSIX allow a call to `pthread_cond_signal' or `pthread_cond_broadcast'
- * even though the associated mutex/mutexes isn't/aren't locked by the
- * caller. Our implementation do not allow that in order to avoid a
- * performance penalty. That is, all associated mutexes *need* to be
- * locked by the caller of erts_smp_cnd_signal()/erts_smp_cnd_broadcast()!
- */
-
-ERTS_GLB_INLINE void
-erts_smp_cnd_signal(erts_smp_cnd_t *cnd)
-{
-#ifdef ERTS_SMP
-    erts_cnd_signal(cnd);
-#endif
-}
-
-
-ERTS_GLB_INLINE void
-erts_smp_cnd_broadcast(erts_smp_cnd_t *cnd)
-{
-#ifdef ERTS_SMP
-    erts_cnd_broadcast(cnd);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_rwmtx_set_reader_group(int no)
-{
-#ifdef ERTS_SMP
-    erts_rwmtx_set_reader_group(no);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_rwmtx_init(erts_smp_rwmtx_t *rwmtx,
-                    char *name,
-                    Eterm extra,
-                    erts_lock_flags_t flags)
-{
-#ifdef ERTS_SMP
-    erts_smp_rwmtx_init_opt(rwmtx, NULL, name, extra, flags);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_rwmtx_init_opt(erts_smp_rwmtx_t *rwmtx,
-                        erts_smp_rwmtx_opt_t *opt,
-                        char *name,
-                        Eterm extra,
-                        erts_lock_flags_t flags)
-{
-#ifdef ERTS_SMP
-    erts_rwmtx_init_opt(rwmtx, opt, name, extra, flags);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_rwmtx_destroy(erts_smp_rwmtx_t *rwmtx)
-{
-#ifdef ERTS_SMP
-    erts_rwmtx_destroy(rwmtx);
-#endif
-}
-
-ERTS_GLB_INLINE int
-#ifdef ERTS_ENABLE_LOCK_POSITION
-erts_smp_rwmtx_tryrlock_x(erts_smp_rwmtx_t *rwmtx, char *file, unsigned int line)
-#else
-erts_smp_rwmtx_tryrlock(erts_smp_rwmtx_t *rwmtx)
-#endif
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_POSITION)
-    return erts_rwmtx_tryrlock_x(rwmtx, file, line);
-#elif defined(ERTS_SMP)
-    return erts_rwmtx_tryrlock(rwmtx);
-#else
-    return 0;
-#endif
-}
-
-ERTS_GLB_INLINE void
-#ifdef ERTS_ENABLE_LOCK_POSITION
-erts_smp_rwmtx_rlock_x(erts_smp_rwmtx_t *rwmtx, char *file, unsigned int line)
-#else
-erts_smp_rwmtx_rlock(erts_smp_rwmtx_t *rwmtx)
-#endif
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_POSITION)
-    erts_rwmtx_rlock_x(rwmtx, file, line);
-#elif defined(ERTS_SMP)
-    erts_rwmtx_rlock(rwmtx);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_rwmtx_runlock(erts_smp_rwmtx_t *rwmtx)
-{
-#ifdef ERTS_SMP
-    erts_rwmtx_runlock(rwmtx);
-#endif
-}
-
-
-ERTS_GLB_INLINE int
-#ifdef ERTS_ENABLE_LOCK_POSITION
-erts_smp_rwmtx_tryrwlock_x(erts_smp_rwmtx_t *rwmtx, char *file, unsigned int line)
-#else
-erts_smp_rwmtx_tryrwlock(erts_smp_rwmtx_t *rwmtx)
-#endif
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_POSITION)
-    return erts_rwmtx_tryrwlock_x(rwmtx, file, line);
-#elif defined(ERTS_SMP)
-    return erts_rwmtx_tryrwlock(rwmtx);
-#else
-    return 0;
-#endif
-}
-
-ERTS_GLB_INLINE void
-#ifdef ERTS_ENABLE_LOCK_POSITION
-erts_smp_rwmtx_rwlock_x(erts_smp_rwmtx_t *rwmtx, char *file, unsigned int line)
-#else
-erts_smp_rwmtx_rwlock(erts_smp_rwmtx_t *rwmtx)
-#endif
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_POSITION)
-    erts_rwmtx_rwlock_x(rwmtx, file, line);
-#elif defined(ERTS_SMP)
-    erts_rwmtx_rwlock(rwmtx);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_rwmtx_rwunlock(erts_smp_rwmtx_t *rwmtx)
-{
-#ifdef ERTS_SMP
-    erts_rwmtx_rwunlock(rwmtx);
-#endif
-}
-
-#if 0 /* The following rwmtx function names are
-	 reserved for potential future use. */ 
-
-/* Try upgrade from r-locked state to rw-locked state */
-ERTS_GLB_INLINE int
-erts_smp_rwmtx_trywlock(erts_smp_rwmtx_t *rwmtx)
-{
-    return 0;
-}
-
-/* Upgrade from r-locked state to rw-locked state */
-ERTS_GLB_INLINE void
-erts_smp_rwmtx_wlock(erts_smp_rwmtx_t *rwmtx)
-{
-
-}
-
-/* Downgrade from rw-locked state to r-locked state */
-ERTS_GLB_INLINE void
-erts_smp_rwmtx_wunlock(erts_smp_rwmtx_t *rwmtx)
-{
-
-}
-
-#endif
-
-ERTS_GLB_INLINE int
-erts_smp_lc_rwmtx_is_rlocked(erts_smp_rwmtx_t *mtx)
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
-    return erts_lc_rwmtx_is_rlocked(mtx);
-#else
-    return 0;
-#endif
-}
-
-ERTS_GLB_INLINE int
-erts_smp_lc_rwmtx_is_rwlocked(erts_smp_rwmtx_t *mtx)
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
-    return erts_lc_rwmtx_is_rwlocked(mtx);
-#else
-    return 0;
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_spinlock_init(erts_smp_spinlock_t *lock, char *name, Eterm extra, erts_lock_flags_t flags)
-{
-#ifdef ERTS_SMP
-    erts_spinlock_init(lock, name, extra, flags);
-#else
-    (void)lock;
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_spinlock_destroy(erts_smp_spinlock_t *lock)
-{
-#ifdef ERTS_SMP
-    erts_spinlock_destroy(lock);
-#else
-    (void)lock;
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_spin_unlock(erts_smp_spinlock_t *lock)
-{
-#ifdef ERTS_SMP
-    erts_spin_unlock(lock);
-#else
-    (void)lock;
-#endif
-}
-
-ERTS_GLB_INLINE void
-#ifdef ERTS_ENABLE_LOCK_POSITION
-erts_smp_spin_lock_x(erts_smp_spinlock_t *lock, char *file, unsigned int line)
-#else
-erts_smp_spin_lock(erts_smp_spinlock_t *lock)
-#endif
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_POSITION)
-    erts_spin_lock_x(lock, file, line);
-#elif defined(ERTS_SMP)
-    erts_spin_lock(lock);
-#else
-    (void)lock;
-#endif
-}
-
-ERTS_GLB_INLINE int
-erts_smp_lc_spinlock_is_locked(erts_smp_spinlock_t *lock)
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
-    return erts_lc_spinlock_is_locked(lock);
-#else
-    return 0;
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_rwlock_init(erts_smp_rwlock_t *lock, char *name, Eterm extra, erts_lock_flags_t flags)
-{
-#ifdef ERTS_SMP
-    erts_rwlock_init(lock, name, extra, flags);
-#else
-    (void)lock;
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_rwlock_destroy(erts_smp_rwlock_t *lock)
-{
-#ifdef ERTS_SMP
-    erts_rwlock_destroy(lock);
-#else
-    (void)lock;
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_read_unlock(erts_smp_rwlock_t *lock)
-{
-#ifdef ERTS_SMP
-    erts_read_unlock(lock);
-#else
-    (void)lock;
-#endif
-}
-
-ERTS_GLB_INLINE void
-#ifdef ERTS_ENABLE_LOCK_POSITION
-erts_smp_read_lock_x(erts_smp_rwlock_t *lock, char *file, unsigned int line)
-#else
-erts_smp_read_lock(erts_smp_rwlock_t *lock)
-#endif 
-{
-#if defined(ERTS_ENABLE_LOCK_POSITION) && defined(ERTS_SMP)
-    erts_read_lock_x(lock, file, line);
-#elif defined(ERTS_SMP)
-    erts_read_lock(lock);
-#else
-    (void)lock;
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_write_unlock(erts_smp_rwlock_t *lock)
-{
-#ifdef ERTS_SMP
-    erts_write_unlock(lock);
-#else
-    (void)lock;
-#endif
-}
-
-ERTS_GLB_INLINE void
-#ifdef ERTS_ENABLE_LOCK_POSITION
-erts_smp_write_lock_x(erts_smp_rwlock_t *lock, char *file, unsigned int line)
-#else
-erts_smp_write_lock(erts_smp_rwlock_t *lock)
-#endif 
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_POSITION)
-    erts_write_lock_x(lock, file, line);
-#elif defined(ERTS_SMP)
-    erts_write_lock(lock);
-#else
-    (void)lock;
-#endif
-}
-
-ERTS_GLB_INLINE int
-erts_smp_lc_rwlock_is_rlocked(erts_smp_rwlock_t *lock)
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
-    return erts_lc_rwlock_is_rlocked(lock);
-#else
-    return 0;
-#endif
-}
-
-ERTS_GLB_INLINE int
-erts_smp_lc_rwlock_is_rwlocked(erts_smp_rwlock_t *lock)
-{
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
-    return erts_lc_rwlock_is_rwlocked(lock);
-#else
-    return 0;
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_tsd_key_create(erts_smp_tsd_key_t *keyp, char* keyname)
-{
-#ifdef ERTS_SMP
-    erts_tsd_key_create(keyp,keyname);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_tsd_key_delete(erts_smp_tsd_key_t key)
-{
-#ifdef ERTS_SMP
-    erts_tsd_key_delete(key);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_tsd_set(erts_smp_tsd_key_t key, void *value)
-{
-#ifdef ERTS_SMP
-    erts_tsd_set(key, value);
-#endif
-}
-
-ERTS_GLB_INLINE void *
-erts_smp_tsd_get(erts_smp_tsd_key_t key)
-{
-#ifdef ERTS_SMP
-    return erts_tsd_get(key);
-#else
-    return NULL;
-#endif
-}
-
-#ifdef ERTS_THR_HAVE_SIG_FUNCS
-#define ERTS_SMP_THR_HAVE_SIG_FUNCS 1
-
-ERTS_GLB_INLINE void
-erts_smp_thr_sigmask(int how, const sigset_t *set, sigset_t *oset)
-{
-#ifdef ERTS_SMP
-    erts_thr_sigmask(how, set, oset);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_thr_sigwait(const sigset_t *set, int *sig)
-{
-#ifdef ERTS_SMP
-    erts_thr_sigwait(set, sig);
-#endif
-}
-
-#endif /* #ifdef ERTS_THR_HAVE_SIG_FUNCS */
-
-#endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
-
-#endif /* ERL_SMP_H */
-
-#ifdef ERTS_UNDEF_DEPRECATED_ATOMICS
-
-/* Deprecated functions to replace */
-
-#undef erts_smp_atomic_init
-#undef erts_smp_atomic_set
-#undef erts_smp_atomic_read
-#undef erts_smp_atomic_inctest
-#undef erts_smp_atomic_dectest
-#undef erts_smp_atomic_inc
-#undef erts_smp_atomic_dec
-#undef erts_smp_atomic_addtest
-#undef erts_smp_atomic_add
-#undef erts_smp_atomic_xchg
-#undef erts_smp_atomic_cmpxchg
-#undef erts_smp_atomic_bor
-#undef erts_smp_atomic_band
-
-#undef erts_smp_atomic32_init
-#undef erts_smp_atomic32_set
-#undef erts_smp_atomic32_read
-#undef erts_smp_atomic32_inctest
-#undef erts_smp_atomic32_dectest
-#undef erts_smp_atomic32_inc
-#undef erts_smp_atomic32_dec
-#undef erts_smp_atomic32_addtest
-#undef erts_smp_atomic32_add
-#undef erts_smp_atomic32_xchg
-#undef erts_smp_atomic32_cmpxchg
-#undef erts_smp_atomic32_bor
-#undef erts_smp_atomic32_band
-
-#endif
diff --git a/erts/emulator/beam/erl_term.h b/erts/emulator/beam/erl_term.h
index 842802f8d9..7d42d1b396 100644
--- a/erts/emulator/beam/erl_term.h
+++ b/erts/emulator/beam/erl_term.h
@@ -55,9 +55,6 @@ struct erl_node_; /* Declared in erl_node_tables.h */
 #if defined(ARCH_64)
 #  define TAG_PTR_MASK__	0x7
 #  if !defined(ERTS_HAVE_OS_PHYSICAL_MEMORY_RESERVATION)
-#    ifdef HIPE
-#      error Hipe on 64-bit needs a real mmap as it does not support the literal tag
-#    endif
 #    define TAG_LITERAL_PTR	0x4
 #  else
 #    undef TAG_LITERAL_PTR
@@ -270,7 +267,6 @@ _ET_DECLARE_CHECKED(Eterm*,list_val,Wterm)
 #define is_byte(x)	(((x) & ((~(Uint)0 << (_TAG_IMMED1_SIZE+8)) + _TAG_IMMED1_MASK)) == _TAG_IMMED1_SMALL)
 #define is_valid_bit_size(x) (((Sint)(x)) >= 0 && ((x) & 0x7F) == _TAG_IMMED1_SMALL)
 #define is_not_valid_bit_size(x) (!is_valid_bit_size((x)))
-#define MY_IS_SSMALL(x) (((Uint) ((((x)) >> (SMALL_BITS-1)) + 1)) < 2)
 #define _unchecked_unsigned_val(x)	((x) >> _TAG_IMMED1_SIZE)
 _ET_DECLARE_CHECKED(Uint,unsigned_val,Eterm)
 #define unsigned_val(x)	_ET_APPLY(unsigned_val,(x))
@@ -863,7 +859,7 @@ do {									\
   ((ErtsMRefThing *) (Hp))->mb = (Binp);				\
   ((ErtsMRefThing *) (Hp))->next = (Ohp)->first;			\
   (Ohp)->first = (struct erl_off_heap_header*) (Hp);			\
-  ASSERT(erts_is_ref_numbers_magic(&(Binp)->refn));			\
+  ASSERT(erts_is_ref_numbers_magic((Binp)->refn));			\
 } while (0)
 
 #endif /* ARCH_32 */
diff --git a/erts/emulator/beam/erl_thr_progress.c b/erts/emulator/beam/erl_thr_progress.c
index 2a9f276e02..96824dc06e 100644
--- a/erts/emulator/beam/erl_thr_progress.c
+++ b/erts/emulator/beam/erl_thr_progress.c
@@ -80,7 +80,6 @@
 #include "erl_thr_progress.h"
 #include "global.h"
 
-#ifdef ERTS_SMP
 
 #define ERTS_THR_PRGR_DBG_CHK_WAKEUP_REQUEST_VALUE 0
 
@@ -1513,4 +1512,3 @@ void erts_thr_progress_dbg_print_state(void)
 
 }
 
-#endif
diff --git a/erts/emulator/beam/erl_thr_progress.h b/erts/emulator/beam/erl_thr_progress.h
index b2894ba1fe..8c029bcf99 100644
--- a/erts/emulator/beam/erl_thr_progress.h
+++ b/erts/emulator/beam/erl_thr_progress.h
@@ -28,23 +28,11 @@
  * Author: 	Rickard Green
  */
 
-#if !defined(ERL_THR_PROGRESS_H__TSD_TYPE__)
+#ifndef ERL_THR_PROGRESS_H__TSD_TYPE__
 #define ERL_THR_PROGRESS_H__TSD_TYPE__
 
 #include "sys.h"
 
-#ifndef ERTS_SMP
-
-#define erts_smp_thr_progress_block() ((void) 0)
-#define erts_smp_thr_progress_unblock() ((void) 0)
-#define erts_smp_thr_progress_is_blocking() 1
-
-#else /* ERTS_SMP */
-
-#define erts_smp_thr_progress_block erts_thr_progress_block
-#define erts_smp_thr_progress_unblock erts_thr_progress_unblock
-#define erts_smp_thr_progress_is_blocking erts_thr_progress_is_blocking
-
 void erts_thr_progress_block(void);
 void erts_thr_progress_unblock(void);
 int erts_thr_progress_is_blocking(void);
@@ -87,13 +75,10 @@ typedef struct {
 int erts_thr_progress_fatal_error_block(ErtsThrPrgrData *tmp_tpd_bufp);
 void erts_thr_progress_fatal_error_wait(SWord timeout);
 
-#endif /* ERTS_SMP */
 
 typedef struct ErtsThrPrgrLaterOp_ ErtsThrPrgrLaterOp;
 struct ErtsThrPrgrLaterOp_ {
-#ifdef ERTS_SMP
     ErtsThrPrgrVal later;
-#endif
     void (*func)(void *);
     void *data;
     ErtsThrPrgrLaterOp *next;
@@ -107,7 +92,6 @@ struct ErtsThrPrgrLaterOp_ {
 #include "erl_threads.h"
 #include "erl_process.h"
 
-#ifdef ERTS_SMP
 
 /* ERTS_THR_PRGR_VAL_FIRST should only be used when initializing... */
 #define ERTS_THR_PRGR_VAL_FIRST ((ErtsThrPrgrVal) 0)
@@ -324,6 +308,5 @@ erts_thr_progress_has_reached(ErtsThrPrgrVal val)
 
 #endif
 
-#endif /* ERTS_SMP */
 
 #endif
diff --git a/erts/emulator/beam/erl_thr_queue.c b/erts/emulator/beam/erl_thr_queue.c
index f56d0828dd..548c2768e5 100644
--- a/erts/emulator/beam/erl_thr_queue.c
+++ b/erts/emulator/beam/erl_thr_queue.c
@@ -87,32 +87,10 @@
 
 #define ERTS_THR_Q_MAX_FINI_DEQ_OPS 50
 
-#ifdef ERTS_SMP
 ERTS_SCHED_PREF_QUICK_ALLOC_IMPL(sl_element,
 				 ErtsThrQElement_t,
 				 1000,
 				 ERTS_ALC_T_THR_Q_EL_SL)
-#else
-
-static void
-init_sl_element_alloc(void)
-{
-}
-
-static ErtsThrQElement_t *
-sl_element_alloc(void)
-{
-    return erts_alloc(ERTS_ALC_T_THR_Q_EL_SL,
-		      sizeof(ErtsThrQElement_t));
-}
-
-static void
-sl_element_free(ErtsThrQElement_t *p)
-{
-    erts_free(ERTS_ALC_T_THR_Q_EL_SL, p);
-}
-
-#endif
 
 #define ErtsThrQDirtyReadEl(A) \
     ((ErtsThrQElement_t *) erts_atomic_read_dirty((A)))
@@ -135,14 +113,6 @@ static void noop_callback(void *arg) { }
 void
 erts_thr_q_initialize(ErtsThrQ_t *q, ErtsThrQInit_t *qi)
 {
-#ifndef USE_THREADS
-    q->init = *qi;
-    if (!q->init.notify)
-	q->init.notify = noop_callback;
-    q->first = NULL;
-    q->last = NULL;
-    q->q.blk = NULL;
-#else
     erts_atomic_init_nob(&q->tail.data.marker.next, ERTS_AINT_NULL);
     q->tail.data.marker.data.ptr = NULL;
     erts_atomic_init_nob(&q->tail.data.last,
@@ -164,10 +134,8 @@ erts_thr_q_initialize(ErtsThrQ_t *q, ErtsThrQInit_t *qi)
     q->head.deq_fini.automatic = qi->auto_finalize_dequeue;
     q->head.deq_fini.start = NULL;
     q->head.deq_fini.end = NULL;
-#ifdef ERTS_SMP
     q->head.next.thr_progress = erts_thr_progress_current();
     q->head.next.thr_progress_reached = 1;
-#endif
     q->head.next.um_refc_ix = 1;
     q->head.next.unref_end = &q->tail.data.marker;
     q->head.used_marker = 1;
@@ -176,15 +144,12 @@ erts_thr_q_initialize(ErtsThrQ_t *q, ErtsThrQInit_t *qi)
     q->q.finalizing = 0;
     q->q.live = qi->live.queue;
     q->q.blk = NULL;
-#endif
 }
 
 ErtsThrQCleanState_t
 erts_thr_q_finalize(ErtsThrQ_t *q)
 {
-#ifdef USE_THREADS
     q->q.finalizing = 1;
-#endif
     while (erts_thr_q_dequeue(q));
     return erts_thr_q_clean(q);
 }
@@ -229,7 +194,6 @@ erts_thr_q_destroy(ErtsThrQ_t *q)
     return erts_thr_q_finalize(q);
 }
 
-#ifdef USE_THREADS
 
 static void
 destroy(ErtsThrQ_t *q)
@@ -249,7 +213,6 @@ destroy(ErtsThrQ_t *q)
     erts_free(atype, q->q.blk);
 }
 
-#endif
 
 static ERTS_INLINE ErtsThrQElement_t *
 element_live_alloc(ErtsThrQLive_t live)
@@ -267,11 +230,7 @@ static ERTS_INLINE ErtsThrQElement_t *
 element_alloc(ErtsThrQ_t *q)
 {
     ErtsThrQLive_t live;
-#ifdef USE_THREADS
     live = q->tail.data.live;
-#else
-    live = q->init.live.objects;
-#endif
     return element_live_alloc(live);
 }
 
@@ -291,15 +250,10 @@ static ERTS_INLINE void
 element_free(ErtsThrQ_t *q, ErtsThrQElement_t *el)
 {
     ErtsThrQLive_t live;
-#ifdef USE_THREADS
     live = q->head.live;
-#else
-    live = q->init.live.objects;
-#endif
     element_live_free(live, el);
 }
 
-#ifdef USE_THREADS
 
 static ERTS_INLINE ErtsThrQElement_t *
 enqueue_managed(ErtsThrQ_t *q, ErtsThrQElement_t *this)
@@ -423,11 +377,9 @@ clean(ErtsThrQ_t *q, int max_ops, int do_notify)
 	return ERTS_THR_Q_CLEAN;
     }
 
-#ifdef ERTS_SMP
     if (q->head.next.thr_progress_reached
 	|| erts_thr_progress_has_reached(q->head.next.thr_progress)) {
 	q->head.next.thr_progress_reached = 1;
-#endif
 	um_refc_ix = q->head.next.um_refc_ix;
 	if (erts_atomic_read_acqb(&q->tail.data.um_refc[um_refc_ix]) == 0) {
 	    /* Move unreferenced end pointer forward... */
@@ -439,23 +391,17 @@ clean(ErtsThrQ_t *q, int max_ops, int do_notify)
 		ilast = (erts_aint_t) enqueue_marker(q, NULL);
 
 	    if (q->head.unref_end == (ErtsThrQElement_t *) ilast)
-		ERTS_SMP_MEMORY_BARRIER;
+		ERTS_THR_MEMORY_BARRIER;
 	    else {
 		q->head.next.unref_end = (ErtsThrQElement_t *) ilast;
-#ifdef ERTS_SMP
 		q->head.next.thr_progress = erts_thr_progress_later(NULL);
-#endif
 		erts_atomic32_set_relb(&q->tail.data.um_refc_ix,
 				       um_refc_ix);
 		q->head.next.um_refc_ix = um_refc_ix == 0 ? 1 : 0;
-#ifdef ERTS_SMP
 		q->head.next.thr_progress_reached = 0;
-#endif
 	    }
 	}
-#ifdef ERTS_SMP
     }
-#endif
 
     head = ErtsThrQDirtyReadEl(&q->head.head);
     if (q->head.first == head) {
@@ -489,9 +435,7 @@ clean(ErtsThrQ_t *q, int max_ops, int do_notify)
 
 check_thr_progress:
 
-#ifdef ERTS_SMP
     if (q->head.next.thr_progress_reached)
-#endif
     {
 	int um_refc_ix = q->head.next.um_refc_ix;
 	if (erts_atomic_read_acqb(&q->tail.data.um_refc[um_refc_ix]) == 0) {
@@ -505,24 +449,16 @@ check_thr_progress:
     return ERTS_THR_Q_NEED_THR_PRGR;
 }
 
-#endif
 
 ErtsThrQCleanState_t
 erts_thr_q_clean(ErtsThrQ_t *q)
 {
-#ifdef USE_THREADS
     return clean(q, ERTS_THR_Q_MAX_SCHED_CLEAN_OPS, 0);
-#else
-    return ERTS_THR_Q_CLEAN;
-#endif
 }
 
 ErtsThrQCleanState_t
 erts_thr_q_inspect(ErtsThrQ_t *q, int ensure_empty)
 {
-#ifndef USE_THREADS
-    return ERTS_THR_Q_CLEAN;
-#else
     ErtsThrQElement_t *head = ErtsThrQDirtyReadEl(&q->head.head);
     if (ensure_empty) {
 	erts_aint_t inext;
@@ -553,39 +489,21 @@ erts_thr_q_inspect(ErtsThrQ_t *q, int ensure_empty)
     if (q->head.first != q->head.unref_end)
 	return ERTS_THR_Q_DIRTY;
 
-#ifdef ERTS_SMP
     if (q->head.next.thr_progress_reached)
-#endif
     {
 	int um_refc_ix = q->head.next.um_refc_ix;
 	if (erts_atomic_read_acqb(&q->tail.data.um_refc[um_refc_ix]) == 0)
 	    return ERTS_THR_Q_DIRTY;
     }
     return ERTS_THR_Q_NEED_THR_PRGR;
-#endif
 }
 
 static void
 enqueue(ErtsThrQ_t *q, void *data, ErtsThrQElement_t *this)
 {
-#ifndef USE_THREADS
-    ASSERT(data);
-
-    this->next = NULL;
-    this->data.ptr = data;
-
-    if (q->last)
-	q->last->next = this;
-    else {
-	q->first = q->last = this;
-	q->init.notify(q->init.arg);
-    }
-#else
     int notify;
     int um_refc_ix = 0;
-#ifdef ERTS_SMP
     int unmanaged_thread;
-#endif
 
 #if ERTS_THR_Q_DBG_CHK_DATA
     if (!data)
@@ -596,10 +514,8 @@ enqueue(ErtsThrQ_t *q, void *data, ErtsThrQElement_t *this)
 
     this->data.ptr = data;
 
-#ifdef ERTS_SMP
     unmanaged_thread = !erts_thr_progress_is_managed_thread();
     if (unmanaged_thread)
-#endif
     {
 	um_refc_ix = erts_atomic32_read_acqb(&q->tail.data.um_refc_ix);
 	while (1) {
@@ -616,9 +532,7 @@ enqueue(ErtsThrQ_t *q, void *data, ErtsThrQElement_t *this)
     notify = this == enqueue_managed(q, this);
 	
 
-#ifdef ERTS_SMP
     if (unmanaged_thread)
-#endif
     {
 	if (notify)
 	    erts_atomic_dec_relb(&q->tail.data.um_refc[um_refc_ix]);
@@ -627,7 +541,6 @@ enqueue(ErtsThrQ_t *q, void *data, ErtsThrQElement_t *this)
     }
     if (notify)
 	q->tail.data.notify(q->tail.data.arg);
-#endif
 }
 
 void
@@ -645,9 +558,6 @@ erts_thr_q_prepare_enqueue(ErtsThrQ_t *q)
 int
 erts_thr_q_get_finalize_dequeue_data(ErtsThrQ_t *q, ErtsThrQFinDeQ_t *fdp)
 {
-#ifndef USE_THREADS
-    return 0;
-#else
 #ifdef DEBUG
     if (!q->head.deq_fini.start) {
 	ASSERT(!q->head.deq_fini.end);
@@ -670,14 +580,12 @@ erts_thr_q_get_finalize_dequeue_data(ErtsThrQ_t *q, ErtsThrQFinDeQ_t *fdp)
     q->head.deq_fini.start = NULL;
     q->head.deq_fini.end = NULL;
     return fdp->start != NULL;
-#endif
 }
 
 void
 erts_thr_q_append_finalize_dequeue_data(ErtsThrQFinDeQ_t *fdp0,
 					ErtsThrQFinDeQ_t *fdp1)
 {
-#ifdef USE_THREADS
     if (fdp1->start) {
 	if (fdp0->end)
 	    ErtsThrQDirtySetEl(&fdp0->end->next, fdp1->start);
@@ -685,13 +593,11 @@ erts_thr_q_append_finalize_dequeue_data(ErtsThrQFinDeQ_t *fdp0,
 	    fdp0->start = fdp1->start;
 	fdp0->end = fdp1->end;
     }
-#endif
 }
 
 
 int erts_thr_q_finalize_dequeue(ErtsThrQFinDeQ_t *state)
 {
-#ifdef USE_THREADS
     ErtsThrQElement_t *start = state->start;
     if (start) {
 	ErtsThrQLive_t live;
@@ -710,17 +616,14 @@ int erts_thr_q_finalize_dequeue(ErtsThrQFinDeQ_t *state)
 	    return 1; /* More to do */
 	state->end = NULL;
     }
-#endif
     return 0;
 }
 
 void
 erts_thr_q_finalize_dequeue_state_init(ErtsThrQFinDeQ_t *state)
 {
-#ifdef USE_THREADS
     state->start = NULL;
     state->end = NULL;
-#endif
 }
 
 
@@ -734,22 +637,6 @@ erts_thr_q_enqueue_prepared(ErtsThrQ_t *q, void *data, ErtsThrQPrepEnQ_t *prep)
 void *
 erts_thr_q_dequeue(ErtsThrQ_t *q)
 {
-#ifndef USE_THREADS
-    void *res;
-    ErtsThrQElement_t *tmp;
-
-    if (!q->first)
-	return NULL;
-    tmp = q->first;
-    res = tmp->data.ptr;
-    q->first = tmp->next;
-    if (!q->first)
-	q->last = NULL;
-
-    element_free(q, tmp);
-
-    return res;
-#else
     ErtsThrQElement_t *head;
     erts_aint_t inext;
     void *res;
@@ -778,7 +665,6 @@ erts_thr_q_dequeue(ErtsThrQ_t *q)
 	   ? ERTS_THR_Q_MAX_DEQUEUE_CLEAN_OPS
 	   : ERTS_THR_Q_MAX_SCHED_CLEAN_OPS), 1);
     return res;
-#endif
 }
 
 #ifdef USE_LTTNG_VM_TRACEPOINTS
@@ -786,14 +672,6 @@ int
 erts_thr_q_length_dirty(ErtsThrQ_t *q)
 {
     int n = 0;
-#ifndef USE_THREADS
-    void *res;
-    ErtsThrQElement_t *tmp;
-
-    for (tmp = q->first; tmp != NULL; tmp = tmp->next) {
-        n++;
-    }
-#else
     ErtsThrQElement_t *e;
     erts_aint_t inext;
 
@@ -808,7 +686,6 @@ erts_thr_q_length_dirty(ErtsThrQ_t *q)
         }
         inext = erts_atomic_read_acqb(&e->next);
     }
-#endif
     return n;
 }
 #endif
diff --git a/erts/emulator/beam/erl_thr_queue.h b/erts/emulator/beam/erl_thr_queue.h
index 705a67af4c..163a25318d 100644
--- a/erts/emulator/beam/erl_thr_queue.h
+++ b/erts/emulator/beam/erl_thr_queue.h
@@ -78,11 +78,7 @@ typedef struct ErtsThrQElement_t_ ErtsThrQElement_t;
 typedef struct ErtsThrQElement_t ErtsThrQPrepEnQ_t;
 
 struct ErtsThrQElement_t_ {
-#ifdef USE_THREADS
     erts_atomic_t next;
-#else
-    ErtsThrQElement_t *next;
-#endif
     union {
 	erts_atomic_t atmc;
 	void *ptr;
@@ -100,7 +96,6 @@ typedef enum {
     ERTS_THR_Q_DIRTY,
 } ErtsThrQCleanState_t;
 
-#ifdef USE_THREADS
 
 typedef struct {
     ErtsThrQElement_t marker;
@@ -108,9 +103,7 @@ typedef struct {
     erts_atomic_t um_refc[2];
     erts_atomic32_t um_refc_ix;
     ErtsThrQLive_t live;
-#ifdef ERTS_SMP
     erts_atomic32_t thr_prgr_clean_scheduled;
-#endif
     void *arg;
     void (*notify)(void *);
 } ErtsThrQTail_t;
@@ -141,10 +134,8 @@ struct ErtsThrQ_t_ {
 	    ErtsThrQElement_t *end;
 	} deq_fini;
 	struct {
-#ifdef ERTS_SMP
 	    ErtsThrPrgrVal thr_progress;
 	    int thr_progress_reached;
-#endif
 	    int um_refc_ix;
 	    ErtsThrQElement_t *unref_end;
 	} next;
@@ -159,18 +150,6 @@ struct ErtsThrQ_t_ {
     } q;
 };
 
-#else /* !USE_THREADS */
-
-struct ErtsThrQ_t_ {
-    ErtsThrQInit_t init;
-    ErtsThrQElement_t *first;
-    ErtsThrQElement_t *last;
-    struct {
-	void *blk;
-    } q;
-};
-
-#endif
 
 void erts_thr_q_init(void);
 void erts_thr_q_initialize(ErtsThrQ_t *, ErtsThrQInit_t *);
@@ -194,19 +173,15 @@ void erts_thr_q_finalize_dequeue_state_init(ErtsThrQFinDeQ_t *);
 int erts_thr_q_length_dirty(ErtsThrQ_t *);
 #endif
 
-#ifdef ERTS_SMP
 ERTS_GLB_INLINE ErtsThrPrgrVal erts_thr_q_need_thr_progress(ErtsThrQ_t *q);
-#endif
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
-#ifdef ERTS_SMP
 ERTS_GLB_INLINE ErtsThrPrgrVal
 erts_thr_q_need_thr_progress(ErtsThrQ_t *q)
 {
     return q->head.next.thr_progress;
 }
-#endif
 
 #endif /* ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
diff --git a/erts/emulator/beam/erl_threads.h b/erts/emulator/beam/erl_threads.h
index 8b5c17d739..aedceb6fc2 100644
--- a/erts/emulator/beam/erl_threads.h
+++ b/erts/emulator/beam/erl_threads.h
@@ -45,11 +45,6 @@
  *      Data dependency read barrier. Orders *only* loads
  *      according to data dependency across the barrier.
  *
- * If thread support has been disabled, these barriers will become no-ops.
- *
- * If the prefix ERTS_THR_ is replaced with ERTS_SMP_, the barriers will
- * be enabled only in the SMP enabled runtime system.
- *
  * --- Atomic operations ---
  *
  * Atomics operations exist for 32-bit, word size, and double word size
@@ -86,20 +81,6 @@
  *          barrier. Load in atomic operation is ordered
  *          before the barrier.
  *
- * If thread support has been disabled, these functions are mapped to
- * functions that performs the same operation, but aren't atomic
- * and don't imply any memory barriers.
- *
- * If the atomic operations are prefixed with erts_smp_ instead of only
- * erts_ the atomic operations will only be atomic in the SMP enabled
- * runtime system, and will be mapped to non-atomic operations without
- * memory barriers in the runtime system without SMP support. Atomic
- * operations with erts_smp_ prefix should use the atomic types
- * erts_smp_atomic32_t, erts_smp_atomic_t, and erts_smp_dw_atomic_t
- * instead of erts_atomic32_t, erts_atomic_t, and erts_dw_atomic_t. The
- * integer data types erts_aint32_t, erts_aint_t, and erts_dw_atomic_t
- * are the same.
- *
  * --- 32-bit atomic operations ---
  *
  * The following 32-bit atomic operations exist. <B> should be
@@ -262,7 +243,6 @@
 #include "erl_lock_flags.h"
 #include "erl_term.h"
 
-#ifdef USE_THREADS
 
 #define ETHR_TRY_INLINE_FUNCS
 #include "ethread.h"
@@ -405,76 +385,6 @@ __decl_noreturn void  __noreturn erts_thr_fatal_error(int, char *);
 #  define ERTS_HAVE_REC_MTX_INIT	ETHR_HAVE_ETHR_REC_MUTEX_INIT
 #endif
 
-#else /* #ifdef USE_THREADS */
-
-#define ERTS_THR_MEMORY_BARRIER
-#define ERTS_THR_WRITE_MEMORY_BARRIER
-#define ERTS_THR_READ_MEMORY_BARRIER
-#define ERTS_THR_DATA_DEPENDENCY_READ_MEMORY_BARRIER
-
-#define ERTS_THR_OPTS_DEFAULT_INITER 0
-typedef int erts_thr_opts_t;
-typedef int erts_thr_init_data_t;
-typedef int erts_thr_late_init_data_t;
-typedef int erts_tid_t;
-typedef int erts_mtx_t;
-typedef int erts_cnd_t;
-#define ERTS_RWMTX_OPT_DEFAULT_INITER {0}
-#define ERTS_RWMTX_TYPE_NORMAL 0
-#define ERTS_RWMTX_TYPE_FREQUENT_READ 0
-#define ERTS_RWMTX_TYPE_EXTREMELY_FREQUENT_READ 0
-#define ERTS_RWMTX_LONG_LIVED 0
-#define ERTS_RWMTX_SHORT_LIVED 0
-#define ERTS_RWMTX_UNKNOWN_LIVED 0
-typedef struct {
-    char type;
-    char lived;
-    int main_spincount;
-    int aux_spincount;
-} erts_rwmtx_opt_t;
-typedef int erts_rwmtx_t;
-typedef int erts_tsd_key_t;
-typedef int erts_tse_t;
-
-typedef struct { SWord sint[2]; } erts_dw_aint_t;
-typedef SWord erts_aint_t;
-typedef Sint32 erts_aint32_t;
-typedef Sint64 erts_aint64_t;
-
-#define erts_dw_atomic_t erts_dw_aint_t
-#define erts_atomic_t erts_aint_t
-#define erts_atomic32_t erts_aint32_t
-#define erts_atomic64_t erts_aint64_t
-
-#if __GNUC__ > 2
-typedef struct { } erts_spinlock_t;
-typedef struct { } erts_rwlock_t;
-#else
-typedef struct { int gcc_is_buggy; } erts_spinlock_t;
-typedef struct { int gcc_is_buggy; } erts_rwlock_t;
-#endif
-
-#ifdef WORDS_BIGENDIAN
-#define ERTS_DW_AINT_LOW_WORD 1
-#define ERTS_DW_AINT_HIGH_WORD 0
-#else
-#define ERTS_DW_AINT_LOW_WORD 0
-#define ERTS_DW_AINT_HIGH_WORD 1
-#endif
-
-#define ERTS_MTX_INITER			0
-#define ERTS_CND_INITER			0
-#define ERTS_THR_INIT_DATA_DEF_INITER	0
-
-#define ERTS_HAVE_REC_MTX_INIT		1
-
-#endif /* #ifdef USE_THREADS */
-
-#define erts_no_dw_atomic_t erts_dw_aint_t
-#define erts_no_atomic_t erts_aint_t
-#define erts_no_atomic32_t erts_aint32_t
-#define erts_no_atomic64_t erts_aint64_t
-
 #define ERTS_AINT_NULL ((erts_aint_t) NULL)
 
 #define ERTS_AINT_T_MAX (~(((erts_aint_t) 1) << (sizeof(erts_aint_t)*8-1)))
@@ -544,79 +454,6 @@ ERTS_GLB_INLINE void erts_rwmtx_runlock(erts_rwmtx_t *rwmtx);
 ERTS_GLB_INLINE void erts_rwmtx_rwunlock(erts_rwmtx_t *rwmtx);
 ERTS_GLB_INLINE int erts_lc_rwmtx_is_rlocked(erts_rwmtx_t *mtx);
 ERTS_GLB_INLINE int erts_lc_rwmtx_is_rwlocked(erts_rwmtx_t *mtx);
-
-ERTS_GLB_INLINE void erts_no_dw_atomic_set(erts_no_dw_atomic_t *var, erts_no_dw_atomic_t *val);
-ERTS_GLB_INLINE void erts_no_dw_atomic_read(erts_no_dw_atomic_t *var, erts_no_dw_atomic_t *val);
-ERTS_GLB_INLINE int erts_no_dw_atomic_cmpxchg(erts_no_dw_atomic_t *var,
-					      erts_no_dw_atomic_t *val,
-					      erts_no_dw_atomic_t *old_val);
-ERTS_GLB_INLINE void erts_no_atomic_set(erts_no_atomic_t *var, erts_aint_t i);
-ERTS_GLB_INLINE erts_aint_t erts_no_atomic_read(erts_no_atomic_t *var);
-ERTS_GLB_INLINE erts_aint_t erts_no_atomic_inc_read(erts_no_atomic_t *incp);
-ERTS_GLB_INLINE erts_aint_t erts_no_atomic_dec_read(erts_no_atomic_t *decp);
-ERTS_GLB_INLINE void erts_no_atomic_inc(erts_no_atomic_t *incp);
-ERTS_GLB_INLINE void erts_no_atomic_dec(erts_no_atomic_t *decp);
-ERTS_GLB_INLINE erts_aint_t erts_no_atomic_add_read(erts_no_atomic_t *addp,
-						    erts_aint_t i);
-ERTS_GLB_INLINE void erts_no_atomic_add(erts_no_atomic_t *addp, erts_aint_t i);
-ERTS_GLB_INLINE erts_aint_t erts_no_atomic_read_bor(erts_no_atomic_t *var,
-						    erts_aint_t mask);
-ERTS_GLB_INLINE erts_aint_t erts_no_atomic_read_band(erts_no_atomic_t *var,
-						     erts_aint_t mask);
-ERTS_GLB_INLINE erts_aint_t erts_no_atomic_xchg(erts_no_atomic_t *xchgp,
-						erts_aint_t new);
-ERTS_GLB_INLINE erts_aint_t erts_no_atomic_cmpxchg(erts_no_atomic_t *xchgp,
-						   erts_aint_t new,
-						   erts_aint_t expected);
-ERTS_GLB_INLINE erts_aint_t erts_no_atomic_read_bset(erts_no_atomic_t *var,
-						     erts_aint_t mask,
-						     erts_aint_t set);
-ERTS_GLB_INLINE void erts_no_atomic32_set(erts_no_atomic32_t *var,
-					  erts_aint32_t i);
-ERTS_GLB_INLINE erts_aint32_t erts_no_atomic32_read(erts_no_atomic32_t *var);
-ERTS_GLB_INLINE erts_aint32_t erts_no_atomic32_inc_read(erts_no_atomic32_t *incp);
-ERTS_GLB_INLINE erts_aint32_t erts_no_atomic32_dec_read(erts_no_atomic32_t *decp);
-ERTS_GLB_INLINE void erts_no_atomic32_inc(erts_no_atomic32_t *incp);
-ERTS_GLB_INLINE void erts_no_atomic32_dec(erts_no_atomic32_t *decp);
-ERTS_GLB_INLINE erts_aint32_t erts_no_atomic32_add_read(erts_no_atomic32_t *addp,
-							erts_aint32_t i);
-ERTS_GLB_INLINE void erts_no_atomic32_add(erts_no_atomic32_t *addp,
-					  erts_aint32_t i);
-ERTS_GLB_INLINE erts_aint32_t erts_no_atomic32_read_bor(erts_no_atomic32_t *var,
-							erts_aint32_t mask);
-ERTS_GLB_INLINE erts_aint32_t erts_no_atomic32_read_band(erts_no_atomic32_t *var,
-							 erts_aint32_t mask);
-ERTS_GLB_INLINE erts_aint32_t erts_no_atomic32_xchg(erts_no_atomic32_t *xchgp,
-						    erts_aint32_t new);
-ERTS_GLB_INLINE erts_aint32_t erts_no_atomic32_cmpxchg(erts_no_atomic32_t *xchgp,
-						       erts_aint32_t new,
-						       erts_aint32_t expected);
-ERTS_GLB_INLINE erts_aint32_t erts_no_atomic32_read_bset(erts_no_atomic32_t *var,
-							 erts_aint32_t mask,
-							 erts_aint32_t set);
-ERTS_GLB_INLINE void erts_no_atomic64_set(erts_no_atomic64_t *var,
-					  erts_aint64_t i);
-ERTS_GLB_INLINE erts_aint64_t erts_no_atomic64_read(erts_no_atomic64_t *var);
-ERTS_GLB_INLINE erts_aint64_t erts_no_atomic64_inc_read(erts_no_atomic64_t *incp);
-ERTS_GLB_INLINE erts_aint64_t erts_no_atomic64_dec_read(erts_no_atomic64_t *decp);
-ERTS_GLB_INLINE void erts_no_atomic64_inc(erts_no_atomic64_t *incp);
-ERTS_GLB_INLINE void erts_no_atomic64_dec(erts_no_atomic64_t *decp);
-ERTS_GLB_INLINE erts_aint64_t erts_no_atomic64_add_read(erts_no_atomic64_t *addp,
-							erts_aint64_t i);
-ERTS_GLB_INLINE void erts_no_atomic64_add(erts_no_atomic64_t *addp,
-					  erts_aint64_t i);
-ERTS_GLB_INLINE erts_aint64_t erts_no_atomic64_read_bor(erts_no_atomic64_t *var,
-							erts_aint64_t mask);
-ERTS_GLB_INLINE erts_aint64_t erts_no_atomic64_read_band(erts_no_atomic64_t *var,
-							 erts_aint64_t mask);
-ERTS_GLB_INLINE erts_aint64_t erts_no_atomic64_xchg(erts_no_atomic64_t *xchgp,
-						    erts_aint64_t new);
-ERTS_GLB_INLINE erts_aint64_t erts_no_atomic64_cmpxchg(erts_no_atomic64_t *xchgp,
-						       erts_aint64_t new,
-						       erts_aint64_t expected);
-ERTS_GLB_INLINE erts_aint64_t erts_no_atomic64_read_bset(erts_no_atomic64_t *var,
-							 erts_aint64_t mask,
-							 erts_aint64_t set);
 ERTS_GLB_INLINE void erts_spinlock_init(erts_spinlock_t *lock,
                                         char *name,
                                         Eterm extra,
@@ -670,13 +507,10 @@ ERTS_GLB_INLINE void erts_thr_sigmask(int how, const sigset_t *set,
 				      sigset_t *oset);
 ERTS_GLB_INLINE void erts_thr_sigwait(const sigset_t *set, int *sig);
 
-#ifdef USE_THREADS
 ERTS_GLB_INLINE void erts_thr_kill(erts_tid_t tid, int sig);
-#endif
 
 #endif /* #ifdef HAVE_ETHR_SIG_FUNCS */
 
-#ifdef USE_THREADS
 
 ERTS_GLB_INLINE erts_aint_t
 erts_atomic_read_bset_nob(erts_atomic_t *var,
@@ -1684,379 +1518,6 @@ erts_atomic64_read_dirty(erts_atomic64_t *var)
 
 #endif /* ARCH_32 */
 
-#else /* !USE_THREADS */
-
-/* Double word size atomics */
-
-#define erts_dw_atomic_init_nob erts_no_dw_atomic_set
-#define erts_dw_atomic_set_nob erts_no_dw_atomic_set
-#define erts_dw_atomic_read_nob erts_no_dw_atomic_read
-#define erts_dw_atomic_cmpxchg_nob erts_no_dw_atomic_cmpxchg
-
-#define erts_dw_atomic_init_mb erts_no_dw_atomic_init
-#define erts_dw_atomic_set_mb erts_no_dw_atomic_set
-#define erts_dw_atomic_read_mb erts_no_dw_atomic_read
-#define erts_dw_atomic_cmpxchg_mb erts_no_dw_atomic_cmpxchg
-
-#define erts_dw_atomic_init_acqb erts_no_dw_atomic_init
-#define erts_dw_atomic_set_acqb erts_no_dw_atomic_set
-#define erts_dw_atomic_read_acqb erts_no_dw_atomic_read
-#define erts_dw_atomic_cmpxchg_acqb erts_no_dw_atomic_cmpxchg
-
-#define erts_dw_atomic_init_relb erts_no_dw_atomic_init
-#define erts_dw_atomic_set_relb erts_no_dw_atomic_set
-#define erts_dw_atomic_read_relb erts_no_dw_atomic_read
-#define erts_dw_atomic_cmpxchg_relb erts_no_dw_atomic_cmpxchg
-
-#define erts_dw_atomic_init_ddrb erts_no_dw_atomic_init
-#define erts_dw_atomic_set_ddrb erts_no_dw_atomic_set
-#define erts_dw_atomic_read_ddrb erts_no_dw_atomic_read
-#define erts_dw_atomic_cmpxchg_ddrb erts_no_dw_atomic_cmpxchg
-
-#define erts_dw_atomic_init_rb erts_no_dw_atomic_init
-#define erts_dw_atomic_set_rb erts_no_dw_atomic_set
-#define erts_dw_atomic_read_rb erts_no_dw_atomic_read
-#define erts_dw_atomic_cmpxchg_rb erts_no_dw_atomic_cmpxchg
-
-#define erts_dw_atomic_init_wb erts_no_dw_atomic_init
-#define erts_dw_atomic_set_wb erts_no_dw_atomic_set
-#define erts_dw_atomic_read_wb erts_no_dw_atomic_read
-#define erts_dw_atomic_cmpxchg_wb erts_no_dw_atomic_cmpxchg
-
-#define erts_dw_atomic_set_dirty erts_no_dw_atomic_set
-#define erts_dw_atomic_read_dirty erts_no_dw_atomic_read
-
-/* Word size atomics */
-
-#define erts_atomic_init_nob erts_no_atomic_set
-#define erts_atomic_set_nob erts_no_atomic_set
-#define erts_atomic_read_nob erts_no_atomic_read
-#define erts_atomic_inc_read_nob erts_no_atomic_inc_read
-#define erts_atomic_dec_read_nob erts_no_atomic_dec_read
-#define erts_atomic_inc_nob erts_no_atomic_inc
-#define erts_atomic_dec_nob erts_no_atomic_dec
-#define erts_atomic_add_read_nob erts_no_atomic_add_read
-#define erts_atomic_add_nob erts_no_atomic_add
-#define erts_atomic_read_bor_nob erts_no_atomic_read_bor
-#define erts_atomic_read_band_nob erts_no_atomic_read_band
-#define erts_atomic_xchg_nob erts_no_atomic_xchg
-#define erts_atomic_cmpxchg_nob erts_no_atomic_cmpxchg
-#define erts_atomic_read_bset_nob erts_no_atomic_read_bset
-
-#define erts_atomic_init_mb erts_no_atomic_set
-#define erts_atomic_set_mb erts_no_atomic_set
-#define erts_atomic_read_mb erts_no_atomic_read
-#define erts_atomic_inc_read_mb erts_no_atomic_inc_read
-#define erts_atomic_dec_read_mb erts_no_atomic_dec_read
-#define erts_atomic_inc_mb erts_no_atomic_inc
-#define erts_atomic_dec_mb erts_no_atomic_dec
-#define erts_atomic_add_read_mb erts_no_atomic_add_read
-#define erts_atomic_add_mb erts_no_atomic_add
-#define erts_atomic_read_bor_mb erts_no_atomic_read_bor
-#define erts_atomic_read_band_mb erts_no_atomic_read_band
-#define erts_atomic_xchg_mb erts_no_atomic_xchg
-#define erts_atomic_cmpxchg_mb erts_no_atomic_cmpxchg
-#define erts_atomic_read_bset_mb erts_no_atomic_read_bset
-
-#define erts_atomic_init_acqb erts_no_atomic_set
-#define erts_atomic_set_acqb erts_no_atomic_set
-#define erts_atomic_read_acqb erts_no_atomic_read
-#define erts_atomic_inc_read_acqb erts_no_atomic_inc_read
-#define erts_atomic_dec_read_acqb erts_no_atomic_dec_read
-#define erts_atomic_inc_acqb erts_no_atomic_inc
-#define erts_atomic_dec_acqb erts_no_atomic_dec
-#define erts_atomic_add_read_acqb erts_no_atomic_add_read
-#define erts_atomic_add_acqb erts_no_atomic_add
-#define erts_atomic_read_bor_acqb erts_no_atomic_read_bor
-#define erts_atomic_read_band_acqb erts_no_atomic_read_band
-#define erts_atomic_xchg_acqb erts_no_atomic_xchg
-#define erts_atomic_cmpxchg_acqb erts_no_atomic_cmpxchg
-#define erts_atomic_read_bset_acqb erts_no_atomic_read_bset
-
-#define erts_atomic_init_relb erts_no_atomic_set
-#define erts_atomic_set_relb erts_no_atomic_set
-#define erts_atomic_read_relb erts_no_atomic_read
-#define erts_atomic_inc_read_relb erts_no_atomic_inc_read
-#define erts_atomic_dec_read_relb erts_no_atomic_dec_read
-#define erts_atomic_inc_relb erts_no_atomic_inc
-#define erts_atomic_dec_relb erts_no_atomic_dec
-#define erts_atomic_add_read_relb erts_no_atomic_add_read
-#define erts_atomic_add_relb erts_no_atomic_add
-#define erts_atomic_read_bor_relb erts_no_atomic_read_bor
-#define erts_atomic_read_band_relb erts_no_atomic_read_band
-#define erts_atomic_xchg_relb erts_no_atomic_xchg
-#define erts_atomic_cmpxchg_relb erts_no_atomic_cmpxchg
-#define erts_atomic_read_bset_relb erts_no_atomic_read_bset
-
-#define erts_atomic_init_ddrb erts_no_atomic_set
-#define erts_atomic_set_ddrb erts_no_atomic_set
-#define erts_atomic_read_ddrb erts_no_atomic_read
-#define erts_atomic_inc_read_ddrb erts_no_atomic_inc_read
-#define erts_atomic_dec_read_ddrb erts_no_atomic_dec_read
-#define erts_atomic_inc_ddrb erts_no_atomic_inc
-#define erts_atomic_dec_ddrb erts_no_atomic_dec
-#define erts_atomic_add_read_ddrb erts_no_atomic_add_read
-#define erts_atomic_add_ddrb erts_no_atomic_add
-#define erts_atomic_read_bor_ddrb erts_no_atomic_read_bor
-#define erts_atomic_read_band_ddrb erts_no_atomic_read_band
-#define erts_atomic_xchg_ddrb erts_no_atomic_xchg
-#define erts_atomic_cmpxchg_ddrb erts_no_atomic_cmpxchg
-#define erts_atomic_read_bset_ddrb erts_no_atomic_read_bset
-
-#define erts_atomic_init_rb erts_no_atomic_set
-#define erts_atomic_set_rb erts_no_atomic_set
-#define erts_atomic_read_rb erts_no_atomic_read
-#define erts_atomic_inc_read_rb erts_no_atomic_inc_read
-#define erts_atomic_dec_read_rb erts_no_atomic_dec_read
-#define erts_atomic_inc_rb erts_no_atomic_inc
-#define erts_atomic_dec_rb erts_no_atomic_dec
-#define erts_atomic_add_read_rb erts_no_atomic_add_read
-#define erts_atomic_add_rb erts_no_atomic_add
-#define erts_atomic_read_bor_rb erts_no_atomic_read_bor
-#define erts_atomic_read_band_rb erts_no_atomic_read_band
-#define erts_atomic_xchg_rb erts_no_atomic_xchg
-#define erts_atomic_cmpxchg_rb erts_no_atomic_cmpxchg
-#define erts_atomic_read_bset_rb erts_no_atomic_read_bset
-
-#define erts_atomic_init_wb erts_no_atomic_set
-#define erts_atomic_set_wb erts_no_atomic_set
-#define erts_atomic_read_wb erts_no_atomic_read
-#define erts_atomic_inc_read_wb erts_no_atomic_inc_read
-#define erts_atomic_dec_read_wb erts_no_atomic_dec_read
-#define erts_atomic_inc_wb erts_no_atomic_inc
-#define erts_atomic_dec_wb erts_no_atomic_dec
-#define erts_atomic_add_read_wb erts_no_atomic_add_read
-#define erts_atomic_add_wb erts_no_atomic_add
-#define erts_atomic_read_bor_wb erts_no_atomic_read_bor
-#define erts_atomic_read_band_wb erts_no_atomic_read_band
-#define erts_atomic_xchg_wb erts_no_atomic_xchg
-#define erts_atomic_cmpxchg_wb erts_no_atomic_cmpxchg
-#define erts_atomic_read_bset_wb erts_no_atomic_read_bset
-
-#define erts_atomic_set_dirty erts_no_atomic_set
-#define erts_atomic_read_dirty erts_no_atomic_read
-
-/* 32-bit atomics */
-
-#define erts_atomic32_init_nob erts_no_atomic32_set
-#define erts_atomic32_set_nob erts_no_atomic32_set
-#define erts_atomic32_read_nob erts_no_atomic32_read
-#define erts_atomic32_inc_read_nob erts_no_atomic32_inc_read
-#define erts_atomic32_dec_read_nob erts_no_atomic32_dec_read
-#define erts_atomic32_inc_nob erts_no_atomic32_inc
-#define erts_atomic32_dec_nob erts_no_atomic32_dec
-#define erts_atomic32_add_read_nob erts_no_atomic32_add_read
-#define erts_atomic32_add_nob erts_no_atomic32_add
-#define erts_atomic32_read_bor_nob erts_no_atomic32_read_bor
-#define erts_atomic32_read_band_nob erts_no_atomic32_read_band
-#define erts_atomic32_xchg_nob erts_no_atomic32_xchg
-#define erts_atomic32_cmpxchg_nob erts_no_atomic32_cmpxchg
-#define erts_atomic32_read_bset_nob erts_no_atomic32_read_bset
-
-#define erts_atomic32_init_mb erts_no_atomic32_set
-#define erts_atomic32_set_mb erts_no_atomic32_set
-#define erts_atomic32_read_mb erts_no_atomic32_read
-#define erts_atomic32_inc_read_mb erts_no_atomic32_inc_read
-#define erts_atomic32_dec_read_mb erts_no_atomic32_dec_read
-#define erts_atomic32_inc_mb erts_no_atomic32_inc
-#define erts_atomic32_dec_mb erts_no_atomic32_dec
-#define erts_atomic32_add_read_mb erts_no_atomic32_add_read
-#define erts_atomic32_add_mb erts_no_atomic32_add
-#define erts_atomic32_read_bor_mb erts_no_atomic32_read_bor
-#define erts_atomic32_read_band_mb erts_no_atomic32_read_band
-#define erts_atomic32_xchg_mb erts_no_atomic32_xchg
-#define erts_atomic32_cmpxchg_mb erts_no_atomic32_cmpxchg
-#define erts_atomic32_read_bset_mb erts_no_atomic32_read_bset
-
-#define erts_atomic32_init_acqb erts_no_atomic32_set
-#define erts_atomic32_set_acqb erts_no_atomic32_set
-#define erts_atomic32_read_acqb erts_no_atomic32_read
-#define erts_atomic32_inc_read_acqb erts_no_atomic32_inc_read
-#define erts_atomic32_dec_read_acqb erts_no_atomic32_dec_read
-#define erts_atomic32_inc_acqb erts_no_atomic32_inc
-#define erts_atomic32_dec_acqb erts_no_atomic32_dec
-#define erts_atomic32_add_read_acqb erts_no_atomic32_add_read
-#define erts_atomic32_add_acqb erts_no_atomic32_add
-#define erts_atomic32_read_bor_acqb erts_no_atomic32_read_bor
-#define erts_atomic32_read_band_acqb erts_no_atomic32_read_band
-#define erts_atomic32_xchg_acqb erts_no_atomic32_xchg
-#define erts_atomic32_cmpxchg_acqb erts_no_atomic32_cmpxchg
-#define erts_atomic32_read_bset_acqb erts_no_atomic32_read_bset
-
-#define erts_atomic32_init_relb erts_no_atomic32_set
-#define erts_atomic32_set_relb erts_no_atomic32_set
-#define erts_atomic32_read_relb erts_no_atomic32_read
-#define erts_atomic32_inc_read_relb erts_no_atomic32_inc_read
-#define erts_atomic32_dec_read_relb erts_no_atomic32_dec_read
-#define erts_atomic32_inc_relb erts_no_atomic32_inc
-#define erts_atomic32_dec_relb erts_no_atomic32_dec
-#define erts_atomic32_add_read_relb erts_no_atomic32_add_read
-#define erts_atomic32_add_relb erts_no_atomic32_add
-#define erts_atomic32_read_bor_relb erts_no_atomic32_read_bor
-#define erts_atomic32_read_band_relb erts_no_atomic32_read_band
-#define erts_atomic32_xchg_relb erts_no_atomic32_xchg
-#define erts_atomic32_cmpxchg_relb erts_no_atomic32_cmpxchg
-#define erts_atomic32_read_bset_relb erts_no_atomic32_read_bset
-
-#define erts_atomic32_init_ddrb erts_no_atomic32_set
-#define erts_atomic32_set_ddrb erts_no_atomic32_set
-#define erts_atomic32_read_ddrb erts_no_atomic32_read
-#define erts_atomic32_inc_read_ddrb erts_no_atomic32_inc_read
-#define erts_atomic32_dec_read_ddrb erts_no_atomic32_dec_read
-#define erts_atomic32_inc_ddrb erts_no_atomic32_inc
-#define erts_atomic32_dec_ddrb erts_no_atomic32_dec
-#define erts_atomic32_add_read_ddrb erts_no_atomic32_add_read
-#define erts_atomic32_add_ddrb erts_no_atomic32_add
-#define erts_atomic32_read_bor_ddrb erts_no_atomic32_read_bor
-#define erts_atomic32_read_band_ddrb erts_no_atomic32_read_band
-#define erts_atomic32_xchg_ddrb erts_no_atomic32_xchg
-#define erts_atomic32_cmpxchg_ddrb erts_no_atomic32_cmpxchg
-#define erts_atomic32_read_bset_ddrb erts_no_atomic32_read_bset
-
-#define erts_atomic32_init_rb erts_no_atomic32_set
-#define erts_atomic32_set_rb erts_no_atomic32_set
-#define erts_atomic32_read_rb erts_no_atomic32_read
-#define erts_atomic32_inc_read_rb erts_no_atomic32_inc_read
-#define erts_atomic32_dec_read_rb erts_no_atomic32_dec_read
-#define erts_atomic32_inc_rb erts_no_atomic32_inc
-#define erts_atomic32_dec_rb erts_no_atomic32_dec
-#define erts_atomic32_add_read_rb erts_no_atomic32_add_read
-#define erts_atomic32_add_rb erts_no_atomic32_add
-#define erts_atomic32_read_bor_rb erts_no_atomic32_read_bor
-#define erts_atomic32_read_band_rb erts_no_atomic32_read_band
-#define erts_atomic32_xchg_rb erts_no_atomic32_xchg
-#define erts_atomic32_cmpxchg_rb erts_no_atomic32_cmpxchg
-#define erts_atomic32_read_bset_rb erts_no_atomic32_read_bset
-
-#define erts_atomic32_init_wb erts_no_atomic32_set
-#define erts_atomic32_set_wb erts_no_atomic32_set
-#define erts_atomic32_read_wb erts_no_atomic32_read
-#define erts_atomic32_inc_read_wb erts_no_atomic32_inc_read
-#define erts_atomic32_dec_read_wb erts_no_atomic32_dec_read
-#define erts_atomic32_inc_wb erts_no_atomic32_inc
-#define erts_atomic32_dec_wb erts_no_atomic32_dec
-#define erts_atomic32_add_read_wb erts_no_atomic32_add_read
-#define erts_atomic32_add_wb erts_no_atomic32_add
-#define erts_atomic32_read_bor_wb erts_no_atomic32_read_bor
-#define erts_atomic32_read_band_wb erts_no_atomic32_read_band
-#define erts_atomic32_xchg_wb erts_no_atomic32_xchg
-#define erts_atomic32_cmpxchg_wb erts_no_atomic32_cmpxchg
-#define erts_atomic32_read_bset_wb erts_no_atomic32_read_bset
-
-#define erts_atomic32_set_dirty erts_no_atomic32_set
-#define erts_atomic32_read_dirty erts_no_atomic32_read
-
-/* 64-bit atomics */
-
-#define erts_atomic64_init_nob erts_no_atomic64_set
-#define erts_atomic64_set_nob erts_no_atomic64_set
-#define erts_atomic64_read_nob erts_no_atomic64_read
-#define erts_atomic64_inc_read_nob erts_no_atomic64_inc_read
-#define erts_atomic64_dec_read_nob erts_no_atomic64_dec_read
-#define erts_atomic64_inc_nob erts_no_atomic64_inc
-#define erts_atomic64_dec_nob erts_no_atomic64_dec
-#define erts_atomic64_add_read_nob erts_no_atomic64_add_read
-#define erts_atomic64_add_nob erts_no_atomic64_add
-#define erts_atomic64_read_bor_nob erts_no_atomic64_read_bor
-#define erts_atomic64_read_band_nob erts_no_atomic64_read_band
-#define erts_atomic64_xchg_nob erts_no_atomic64_xchg
-#define erts_atomic64_cmpxchg_nob erts_no_atomic64_cmpxchg
-#define erts_atomic64_read_bset_nob erts_no_atomic64_read_bset
-
-#define erts_atomic64_init_mb erts_no_atomic64_set
-#define erts_atomic64_set_mb erts_no_atomic64_set
-#define erts_atomic64_read_mb erts_no_atomic64_read
-#define erts_atomic64_inc_read_mb erts_no_atomic64_inc_read
-#define erts_atomic64_dec_read_mb erts_no_atomic64_dec_read
-#define erts_atomic64_inc_mb erts_no_atomic64_inc
-#define erts_atomic64_dec_mb erts_no_atomic64_dec
-#define erts_atomic64_add_read_mb erts_no_atomic64_add_read
-#define erts_atomic64_add_mb erts_no_atomic64_add
-#define erts_atomic64_read_bor_mb erts_no_atomic64_read_bor
-#define erts_atomic64_read_band_mb erts_no_atomic64_read_band
-#define erts_atomic64_xchg_mb erts_no_atomic64_xchg
-#define erts_atomic64_cmpxchg_mb erts_no_atomic64_cmpxchg
-#define erts_atomic64_read_bset_mb erts_no_atomic64_read_bset
-
-#define erts_atomic64_init_acqb erts_no_atomic64_set
-#define erts_atomic64_set_acqb erts_no_atomic64_set
-#define erts_atomic64_read_acqb erts_no_atomic64_read
-#define erts_atomic64_inc_read_acqb erts_no_atomic64_inc_read
-#define erts_atomic64_dec_read_acqb erts_no_atomic64_dec_read
-#define erts_atomic64_inc_acqb erts_no_atomic64_inc
-#define erts_atomic64_dec_acqb erts_no_atomic64_dec
-#define erts_atomic64_add_read_acqb erts_no_atomic64_add_read
-#define erts_atomic64_add_acqb erts_no_atomic64_add
-#define erts_atomic64_read_bor_acqb erts_no_atomic64_read_bor
-#define erts_atomic64_read_band_acqb erts_no_atomic64_read_band
-#define erts_atomic64_xchg_acqb erts_no_atomic64_xchg
-#define erts_atomic64_cmpxchg_acqb erts_no_atomic64_cmpxchg
-#define erts_atomic64_read_bset_acqb erts_no_atomic64_read_bset
-
-#define erts_atomic64_init_relb erts_no_atomic64_set
-#define erts_atomic64_set_relb erts_no_atomic64_set
-#define erts_atomic64_read_relb erts_no_atomic64_read
-#define erts_atomic64_inc_read_relb erts_no_atomic64_inc_read
-#define erts_atomic64_dec_read_relb erts_no_atomic64_dec_read
-#define erts_atomic64_inc_relb erts_no_atomic64_inc
-#define erts_atomic64_dec_relb erts_no_atomic64_dec
-#define erts_atomic64_add_read_relb erts_no_atomic64_add_read
-#define erts_atomic64_add_relb erts_no_atomic64_add
-#define erts_atomic64_read_bor_relb erts_no_atomic64_read_bor
-#define erts_atomic64_read_band_relb erts_no_atomic64_read_band
-#define erts_atomic64_xchg_relb erts_no_atomic64_xchg
-#define erts_atomic64_cmpxchg_relb erts_no_atomic64_cmpxchg
-#define erts_atomic64_read_bset_relb erts_no_atomic64_read_bset
-
-#define erts_atomic64_init_ddrb erts_no_atomic64_set
-#define erts_atomic64_set_ddrb erts_no_atomic64_set
-#define erts_atomic64_read_ddrb erts_no_atomic64_read
-#define erts_atomic64_inc_read_ddrb erts_no_atomic64_inc_read
-#define erts_atomic64_dec_read_ddrb erts_no_atomic64_dec_read
-#define erts_atomic64_inc_ddrb erts_no_atomic64_inc
-#define erts_atomic64_dec_ddrb erts_no_atomic64_dec
-#define erts_atomic64_add_read_ddrb erts_no_atomic64_add_read
-#define erts_atomic64_add_ddrb erts_no_atomic64_add
-#define erts_atomic64_read_bor_ddrb erts_no_atomic64_read_bor
-#define erts_atomic64_read_band_ddrb erts_no_atomic64_read_band
-#define erts_atomic64_xchg_ddrb erts_no_atomic64_xchg
-#define erts_atomic64_cmpxchg_ddrb erts_no_atomic64_cmpxchg
-#define erts_atomic64_read_bset_ddrb erts_no_atomic64_read_bset
-
-#define erts_atomic64_init_rb erts_no_atomic64_set
-#define erts_atomic64_set_rb erts_no_atomic64_set
-#define erts_atomic64_read_rb erts_no_atomic64_read
-#define erts_atomic64_inc_read_rb erts_no_atomic64_inc_read
-#define erts_atomic64_dec_read_rb erts_no_atomic64_dec_read
-#define erts_atomic64_inc_rb erts_no_atomic64_inc
-#define erts_atomic64_dec_rb erts_no_atomic64_dec
-#define erts_atomic64_add_read_rb erts_no_atomic64_add_read
-#define erts_atomic64_add_rb erts_no_atomic64_add
-#define erts_atomic64_read_bor_rb erts_no_atomic64_read_bor
-#define erts_atomic64_read_band_rb erts_no_atomic64_read_band
-#define erts_atomic64_xchg_rb erts_no_atomic64_xchg
-#define erts_atomic64_cmpxchg_rb erts_no_atomic64_cmpxchg
-#define erts_atomic64_read_bset_rb erts_no_atomic64_read_bset
-
-#define erts_atomic64_init_wb erts_no_atomic64_set
-#define erts_atomic64_set_wb erts_no_atomic64_set
-#define erts_atomic64_read_wb erts_no_atomic64_read
-#define erts_atomic64_inc_read_wb erts_no_atomic64_inc_read
-#define erts_atomic64_dec_read_wb erts_no_atomic64_dec_read
-#define erts_atomic64_inc_wb erts_no_atomic64_inc
-#define erts_atomic64_dec_wb erts_no_atomic64_dec
-#define erts_atomic64_add_read_wb erts_no_atomic64_add_read
-#define erts_atomic64_add_wb erts_no_atomic64_add
-#define erts_atomic64_read_bor_wb erts_no_atomic64_read_bor
-#define erts_atomic64_read_band_wb erts_no_atomic64_read_band
-#define erts_atomic64_xchg_wb erts_no_atomic64_xchg
-#define erts_atomic64_cmpxchg_wb erts_no_atomic64_cmpxchg
-#define erts_atomic64_read_bset_wb erts_no_atomic64_read_bset
-
-#define erts_atomic64_set_dirty erts_no_atomic64_set
-#define erts_atomic64_read_dirty erts_no_atomic64_read
-
-#endif /* !USE_THREADS */
 
 #include "erl_msacc.h"
 
@@ -2065,110 +1526,83 @@ erts_atomic64_read_dirty(erts_atomic64_t *var)
 ERTS_GLB_INLINE void
 erts_thr_init(erts_thr_init_data_t *id)
 {
-#ifdef USE_THREADS
     int res = ethr_init(id);
     if (res)
 	erts_thr_fatal_error(res, "initialize thread library");
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_thr_late_init(erts_thr_late_init_data_t *id)
 {
-#ifdef USE_THREADS
     int res = ethr_late_init(id);
     if (res)
 	erts_thr_fatal_error(res, "complete initialization of thread library");
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_thr_create(erts_tid_t *tid, void * (*func)(void *), void *arg,
 		erts_thr_opts_t *opts)
 {
-#ifdef USE_THREADS
     int res = ethr_thr_create(tid, func, arg, opts);
     if (res)
 	erts_thr_fatal_error(res, "create thread");
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_thr_join(erts_tid_t tid, void **thr_res)
 {
-#ifdef USE_THREADS
     int res = ethr_thr_join(tid, thr_res);
     if (res)
 	erts_thr_fatal_error(res, "join thread");
-#endif
 }
 
 
 ERTS_GLB_INLINE void
 erts_thr_detach(erts_tid_t tid)
 {
-#ifdef USE_THREADS
     int res = ethr_thr_detach(tid);
     if (res)
 	erts_thr_fatal_error(res, "detach thread");
-#endif
 }
 
 
 ERTS_GLB_INLINE void
 erts_thr_exit(void *res)
 {
-#ifdef USE_THREADS
     ethr_thr_exit(res);
     erts_thr_fatal_error(0, "terminate thread");
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_thr_install_exit_handler(void (*exit_handler)(void))
 {
-#ifdef USE_THREADS
     int res = ethr_install_exit_handler(exit_handler);
     if (res != 0)
 	erts_thr_fatal_error(res, "install thread exit handler");
-#endif
 }
 
 ERTS_GLB_INLINE erts_tid_t
 erts_thr_self(void)
 {
-#ifdef USE_THREADS
     return ethr_self();
-#else
-    return 0;
-#endif
 }
 
 ERTS_GLB_INLINE int
 erts_thr_getname(erts_tid_t tid, char *buf, size_t len)
 {
-#ifdef USE_THREADS
     return ethr_getname(tid, buf, len);
-#else
-    return -1;
-#endif
 }
 
 
 ERTS_GLB_INLINE int
 erts_equal_tids(erts_tid_t x, erts_tid_t y)
 {
-#ifdef USE_THREADS
     return ethr_equal_tids(x, y);
-#else
-    return 1;
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_mtx_init(erts_mtx_t *mtx, char *name, Eterm extra, erts_lock_flags_t flags)
 {
-#ifdef USE_THREADS
     int res = ethr_mutex_init(&mtx->mtx);
     if (res) {
         erts_thr_fatal_error(res, "initialize mutex");
@@ -2185,13 +1619,11 @@ erts_mtx_init(erts_mtx_t *mtx, char *name, Eterm extra, erts_lock_flags_t flags)
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_init_ref_x(&mtx->lcnt, name, extra, flags);
 #endif
-#endif /* USE_THREADS */
 }
 
 ERTS_GLB_INLINE void
 erts_mtx_init_locked(erts_mtx_t *mtx, char *name, Eterm extra, erts_lock_flags_t flags)
 {
-#ifdef USE_THREADS
     erts_mtx_init(mtx, name, extra, flags);
 
     ethr_mutex_lock(&mtx->mtx);
@@ -2201,13 +1633,11 @@ erts_mtx_init_locked(erts_mtx_t *mtx, char *name, Eterm extra, erts_lock_flags_t
     #ifdef ERTS_ENABLE_LOCK_COUNT
         erts_lcnt_trylock(&mtx->lcnt, 1);
     #endif
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_mtx_destroy(erts_mtx_t *mtx)
 {
-#ifdef USE_THREADS
     int res;
 
     ASSERT(!(mtx->flags & ERTS_LOCK_FLAGS_PROPERTY_STATIC));
@@ -2230,7 +1660,6 @@ erts_mtx_destroy(erts_mtx_t *mtx)
 #endif
 	    erts_thr_fatal_error(res, "destroy mutex");
     }
-#endif
 }
 
 ERTS_GLB_INLINE int
@@ -2240,7 +1669,6 @@ erts_mtx_trylock_x(erts_mtx_t *mtx, char *file, unsigned int line)
 erts_mtx_trylock(erts_mtx_t *mtx)
 #endif
 {
-#ifdef USE_THREADS
     int res;
 
 #ifdef ERTS_ENABLE_LOCK_CHECK
@@ -2262,9 +1690,6 @@ erts_mtx_trylock(erts_mtx_t *mtx)
     erts_lcnt_trylock(&mtx->lcnt, res);
 #endif    
     return res;
-#else
-    return 0;
-#endif
 
 }
 
@@ -2275,7 +1700,6 @@ erts_mtx_lock_x(erts_mtx_t *mtx, char *file, unsigned int line)
 erts_mtx_lock(erts_mtx_t *mtx)
 #endif
 {
-#ifdef USE_THREADS
 #ifdef ERTS_ENABLE_LOCK_CHECK
 #ifdef ERTS_ENABLE_LOCK_POSITION
     erts_lc_lock_x(&mtx->lc, file, line);
@@ -2290,13 +1714,11 @@ erts_mtx_lock(erts_mtx_t *mtx)
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_lock_post_x(&mtx->lcnt, file, line);
 #endif
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_mtx_unlock(erts_mtx_t *mtx)
 {
-#ifdef USE_THREADS
 #ifdef ERTS_ENABLE_LOCK_CHECK
     erts_lc_unlock(&mtx->lc);
 #endif
@@ -2304,13 +1726,12 @@ erts_mtx_unlock(erts_mtx_t *mtx)
     erts_lcnt_unlock(&mtx->lcnt);
 #endif
     ethr_mutex_unlock(&mtx->mtx);
-#endif
 }
 
 ERTS_GLB_INLINE int
 erts_lc_mtx_is_locked(erts_mtx_t *mtx)
 {
-#if defined(USE_THREADS) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     int res;
     erts_lc_lock_t lc = mtx->lc;
     lc.flags = ERTS_LOCK_FLAGS_TYPE_MUTEX;
@@ -2325,17 +1746,14 @@ erts_lc_mtx_is_locked(erts_mtx_t *mtx)
 ERTS_GLB_INLINE void
 erts_cnd_init(erts_cnd_t *cnd)
 {
-#ifdef USE_THREADS
     int res = ethr_cond_init(cnd);
     if (res)
 	erts_thr_fatal_error(res, "initialize condition variable");
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_cnd_destroy(erts_cnd_t *cnd)
 {
-#ifdef USE_THREADS
     int res = ethr_cond_destroy(cnd);
     if (res != 0) {
 #ifdef ERTS_THR_HAVE_BUSY_DESTROY_BUG
@@ -2348,13 +1766,11 @@ erts_cnd_destroy(erts_cnd_t *cnd)
 #endif
 	    erts_thr_fatal_error(res, "destroy condition variable");
     }
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_cnd_wait(erts_cnd_t *cnd, erts_mtx_t *mtx)
 {
-#ifdef USE_THREADS
     int res;
     ERTS_MSACC_PUSH_AND_SET_STATE(ERTS_MSACC_STATE_SLEEP);
 #ifdef ERTS_ENABLE_LOCK_CHECK
@@ -2376,7 +1792,6 @@ erts_cnd_wait(erts_cnd_t *cnd, erts_mtx_t *mtx)
     if (res != 0 && res != EINTR)
 	erts_thr_fatal_error(res, "wait on condition variable");
     ERTS_MSACC_POP_STATE();
-#endif
 }
 
 /*
@@ -2392,18 +1807,14 @@ erts_cnd_wait(erts_cnd_t *cnd, erts_mtx_t *mtx)
 ERTS_GLB_INLINE void
 erts_cnd_signal(erts_cnd_t *cnd)
 {
-#ifdef USE_THREADS
     ethr_cond_signal(cnd);
-#endif
 }
 
 
 ERTS_GLB_INLINE void
 erts_cnd_broadcast(erts_cnd_t *cnd)
 {
-#ifdef USE_THREADS
     ethr_cond_broadcast(cnd);
-#endif
 }
 
 /* rwmutex */
@@ -2411,7 +1822,6 @@ erts_cnd_broadcast(erts_cnd_t *cnd)
 ERTS_GLB_INLINE void
 erts_rwmtx_set_reader_group(int no)
 {
-#ifdef USE_THREADS
     int res;
 #ifdef ERTS_ENABLE_LOCK_CHECK
     erts_lc_check_no_locked_of_type(ERTS_LOCK_TYPE_RWMUTEX);
@@ -2419,13 +1829,11 @@ erts_rwmtx_set_reader_group(int no)
     res = ethr_rwmutex_set_reader_group(no);
     if (res != 0)
 	erts_thr_fatal_error(res, "set reader group");
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_rwmtx_init_opt(erts_rwmtx_t *rwmtx, erts_rwmtx_opt_t *opt,
                     char *name, Eterm extra, erts_lock_flags_t flags) {
-#ifdef USE_THREADS
     int res = ethr_rwmutex_init_opt(&rwmtx->rwmtx, opt);
     if (res != 0) {
         erts_thr_fatal_error(res, "initialize rwmutex");
@@ -2442,7 +1850,6 @@ erts_rwmtx_init_opt(erts_rwmtx_t *rwmtx, erts_rwmtx_opt_t *opt,
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_init_ref_x(&rwmtx->lcnt, name, extra, flags);
 #endif
-#endif /* USE_THREADS */
 }
 
 ERTS_GLB_INLINE void
@@ -2454,7 +1861,6 @@ erts_rwmtx_init(erts_rwmtx_t *rwmtx, char *name, Eterm extra,
 ERTS_GLB_INLINE void
 erts_rwmtx_destroy(erts_rwmtx_t *rwmtx)
 {
-#ifdef USE_THREADS
     int res;
 
     ASSERT(!(rwmtx->flags & ERTS_LOCK_FLAGS_PROPERTY_STATIC));
@@ -2477,7 +1883,6 @@ erts_rwmtx_destroy(erts_rwmtx_t *rwmtx)
 #endif
 	    erts_thr_fatal_error(res, "destroy rwmutex");
     }
-#endif
 }
 
 ERTS_GLB_INLINE int
@@ -2487,7 +1892,6 @@ erts_rwmtx_tryrlock_x(erts_rwmtx_t *rwmtx, char *file, unsigned int line)
 erts_rwmtx_tryrlock(erts_rwmtx_t *rwmtx)
 #endif
 {
-#ifdef USE_THREADS
     int res;
 
 #ifdef ERTS_ENABLE_LOCK_CHECK
@@ -2510,9 +1914,6 @@ erts_rwmtx_tryrlock(erts_rwmtx_t *rwmtx)
 #endif
     
     return res;
-#else
-    return 0;
-#endif
 }
 
 ERTS_GLB_INLINE void
@@ -2522,7 +1923,6 @@ erts_rwmtx_rlock_x(erts_rwmtx_t *rwmtx, char *file, unsigned int line)
 erts_rwmtx_rlock(erts_rwmtx_t *rwmtx)
 #endif
 {
-#ifdef USE_THREADS
 #ifdef ERTS_ENABLE_LOCK_CHECK
 #ifdef ERTS_ENABLE_LOCK_POSITION
     erts_lc_lock_flg_x(&rwmtx->lc, ERTS_LOCK_OPTIONS_READ,file,line);
@@ -2537,13 +1937,11 @@ erts_rwmtx_rlock(erts_rwmtx_t *rwmtx)
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_lock_post_x(&rwmtx->lcnt, file, line);
 #endif
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_rwmtx_runlock(erts_rwmtx_t *rwmtx)
 {
-#ifdef USE_THREADS
 #ifdef ERTS_ENABLE_LOCK_CHECK
     erts_lc_unlock_flg(&rwmtx->lc, ERTS_LOCK_OPTIONS_READ);
 #endif
@@ -2551,7 +1949,6 @@ erts_rwmtx_runlock(erts_rwmtx_t *rwmtx)
     erts_lcnt_unlock_opt(&rwmtx->lcnt, ERTS_LOCK_OPTIONS_READ);
 #endif
     ethr_rwmutex_runlock(&rwmtx->rwmtx);
-#endif
 }
 
 
@@ -2562,7 +1959,6 @@ erts_rwmtx_tryrwlock_x(erts_rwmtx_t *rwmtx, char *file, unsigned int line)
 erts_rwmtx_tryrwlock(erts_rwmtx_t *rwmtx)
 #endif
 {
-#ifdef USE_THREADS
     int res;
 
 #ifdef ERTS_ENABLE_LOCK_CHECK
@@ -2585,9 +1981,6 @@ erts_rwmtx_tryrwlock(erts_rwmtx_t *rwmtx)
 #endif
     
     return res;
-#else
-    return 0;
-#endif
 }
 
 ERTS_GLB_INLINE void
@@ -2597,7 +1990,6 @@ erts_rwmtx_rwlock_x(erts_rwmtx_t *rwmtx, char *file, unsigned int line)
 erts_rwmtx_rwlock(erts_rwmtx_t *rwmtx)
 #endif
 {
-#ifdef USE_THREADS
 #ifdef ERTS_ENABLE_LOCK_CHECK
 #ifdef ERTS_ENABLE_LOCK_POSITION
     erts_lc_lock_flg_x(&rwmtx->lc, ERTS_LOCK_OPTIONS_RDWR,file,line);
@@ -2612,13 +2004,11 @@ erts_rwmtx_rwlock(erts_rwmtx_t *rwmtx)
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_lock_post_x(&rwmtx->lcnt, file, line);
 #endif
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_rwmtx_rwunlock(erts_rwmtx_t *rwmtx)
 {
-#ifdef USE_THREADS
 #ifdef ERTS_ENABLE_LOCK_CHECK
     erts_lc_unlock_flg(&rwmtx->lc, ERTS_LOCK_OPTIONS_RDWR);
 #endif
@@ -2626,7 +2016,6 @@ erts_rwmtx_rwunlock(erts_rwmtx_t *rwmtx)
     erts_lcnt_unlock_opt(&rwmtx->lcnt, ERTS_LOCK_OPTIONS_RDWR);
 #endif
     ethr_rwmutex_rwunlock(&rwmtx->rwmtx);
-#endif
 }
 
 #if 0 /* The following rwmtx function names are
@@ -2658,7 +2047,7 @@ erts_rwmtx_wunlock(erts_rwmtx_t *rwmtx)
 ERTS_GLB_INLINE int
 erts_lc_rwmtx_is_rlocked(erts_rwmtx_t *mtx)
 {
-#if defined(USE_THREADS) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     int res;
     erts_lc_lock_t lc = mtx->lc;
     lc.flags = ERTS_LOCK_TYPE_RWMUTEX;
@@ -2673,7 +2062,7 @@ erts_lc_rwmtx_is_rlocked(erts_rwmtx_t *mtx)
 ERTS_GLB_INLINE int
 erts_lc_rwmtx_is_rwlocked(erts_rwmtx_t *mtx)
 {
-#if defined(USE_THREADS) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     int res;
     erts_lc_lock_t lc = mtx->lc;
     lc.flags = ERTS_LOCK_TYPE_RWMUTEX;
@@ -2685,334 +2074,11 @@ erts_lc_rwmtx_is_rwlocked(erts_rwmtx_t *mtx)
 #endif
 }
 
-/* No atomic ops */
-
-ERTS_GLB_INLINE void
-erts_no_dw_atomic_set(erts_no_dw_atomic_t *var, erts_no_dw_atomic_t *val)
-{
-    var->sint[0] = val->sint[0];
-    var->sint[1] = val->sint[1];
-}
-
-ERTS_GLB_INLINE void
-erts_no_dw_atomic_read(erts_no_dw_atomic_t *var, erts_no_dw_atomic_t *val)
-{
-    val->sint[0] = var->sint[0];
-    val->sint[1] = var->sint[1];
-}
-
-ERTS_GLB_INLINE int erts_no_dw_atomic_cmpxchg(erts_no_dw_atomic_t *var,
-					      erts_no_dw_atomic_t *new_val,
-					      erts_no_dw_atomic_t *old_val)
-{
-    if (var->sint[0] != old_val->sint[0] || var->sint[1] != old_val->sint[1]) {
-	erts_no_dw_atomic_read(var, old_val);
-	return 0;
-    }
-    else {
-	erts_no_dw_atomic_set(var, new_val);
-	return !0;
-    }
-}
-
-ERTS_GLB_INLINE void
-erts_no_atomic_set(erts_no_atomic_t *var, erts_aint_t i)
-{
-    *var = i;
-}
-
-ERTS_GLB_INLINE erts_aint_t
-erts_no_atomic_read(erts_no_atomic_t *var)
-{
-    return *var;
-}
-
-ERTS_GLB_INLINE erts_aint_t
-erts_no_atomic_inc_read(erts_no_atomic_t *incp)
-{
-    return ++(*incp);
-}
-
-ERTS_GLB_INLINE erts_aint_t
-erts_no_atomic_dec_read(erts_no_atomic_t *decp)
-{
-    return --(*decp);
-}
-
-ERTS_GLB_INLINE void
-erts_no_atomic_inc(erts_no_atomic_t *incp)
-{
-    ++(*incp);
-}
-
-ERTS_GLB_INLINE void
-erts_no_atomic_dec(erts_no_atomic_t *decp)
-{
-    --(*decp);
-}
-
-ERTS_GLB_INLINE erts_aint_t
-erts_no_atomic_add_read(erts_no_atomic_t *addp, erts_aint_t i)
-{
-    return *addp += i;
-}
-
-ERTS_GLB_INLINE void
-erts_no_atomic_add(erts_no_atomic_t *addp, erts_aint_t i)
-{
-    *addp += i;
-}
-
-ERTS_GLB_INLINE erts_aint_t
-erts_no_atomic_read_bor(erts_no_atomic_t *var, erts_aint_t mask)
-{
-    erts_aint_t old;
-    old = *var;
-    *var |= mask;
-    return old;
-}
-
-ERTS_GLB_INLINE erts_aint_t
-erts_no_atomic_read_band(erts_no_atomic_t *var, erts_aint_t mask)
-{
-    erts_aint_t old;
-    old = *var;
-    *var &= mask;
-    return old;
-}
-
-ERTS_GLB_INLINE erts_aint_t
-erts_no_atomic_xchg(erts_no_atomic_t *xchgp, erts_aint_t new)
-{
-    erts_aint_t old = *xchgp;
-    *xchgp = new;
-    return old;
-}
-
-ERTS_GLB_INLINE erts_aint_t
-erts_no_atomic_cmpxchg(erts_no_atomic_t *xchgp,
-		       erts_aint_t new,
-		       erts_aint_t expected)
-{
-    erts_aint_t old = *xchgp;
-    if (old == expected)
-        *xchgp = new;
-    return old;
-}
-
-ERTS_GLB_INLINE erts_aint_t
-erts_no_atomic_read_bset(erts_no_atomic_t *var,
-			 erts_aint_t mask,
-			 erts_aint_t set)
-{
-    erts_aint_t old = *var;
-    *var &= ~mask;
-    *var |= (mask & set);
-    return old;
-}
-
-/* atomic32 */
-
-ERTS_GLB_INLINE void
-erts_no_atomic32_set(erts_no_atomic32_t *var, erts_aint32_t i)
-{
-    *var = i;
-}
-
-ERTS_GLB_INLINE erts_aint32_t
-erts_no_atomic32_read(erts_no_atomic32_t *var)
-{
-    return *var;
-}
-
-ERTS_GLB_INLINE erts_aint32_t
-erts_no_atomic32_inc_read(erts_no_atomic32_t *incp)
-{
-    return ++(*incp);
-}
-
-ERTS_GLB_INLINE erts_aint32_t
-erts_no_atomic32_dec_read(erts_no_atomic32_t *decp)
-{
-    return --(*decp);
-}
-
-ERTS_GLB_INLINE void
-erts_no_atomic32_inc(erts_no_atomic32_t *incp)
-{
-    ++(*incp);
-}
-
-ERTS_GLB_INLINE void
-erts_no_atomic32_dec(erts_no_atomic32_t *decp)
-{
-    --(*decp);
-}
-
-ERTS_GLB_INLINE erts_aint32_t
-erts_no_atomic32_add_read(erts_no_atomic32_t *addp, erts_aint32_t i)
-{
-    return *addp += i;
-}
-
-ERTS_GLB_INLINE void
-erts_no_atomic32_add(erts_no_atomic32_t *addp, erts_aint32_t i)
-{
-    *addp += i;
-}
-
-ERTS_GLB_INLINE erts_aint32_t
-erts_no_atomic32_read_bor(erts_no_atomic32_t *var, erts_aint32_t mask)
-{
-    erts_aint32_t old;
-    old = *var;
-    *var |= mask;
-    return old;
-}
-
-ERTS_GLB_INLINE erts_aint32_t
-erts_no_atomic32_read_band(erts_no_atomic32_t *var, erts_aint32_t mask)
-{
-    erts_aint32_t old;
-    old = *var;
-    *var &= mask;
-    return old;
-}
-
-ERTS_GLB_INLINE erts_aint32_t
-erts_no_atomic32_xchg(erts_no_atomic32_t *xchgp, erts_aint32_t new)
-{
-    erts_aint32_t old = *xchgp;
-    *xchgp = new;
-    return old;
-}
-
-ERTS_GLB_INLINE erts_aint32_t
-erts_no_atomic32_cmpxchg(erts_no_atomic32_t *xchgp,
-			 erts_aint32_t new,
-			 erts_aint32_t expected)
-{
-    erts_aint32_t old = *xchgp;
-    if (old == expected)
-        *xchgp = new;
-    return old;
-}
-
-ERTS_GLB_INLINE erts_aint32_t
-erts_no_atomic32_read_bset(erts_no_atomic32_t *var,
-			   erts_aint32_t mask,
-			   erts_aint32_t set)
-{
-    erts_aint32_t old = *var;
-    *var &= ~mask;
-    *var |= (mask & set);
-    return old;
-}
-
-/* atomic64 */
-
-ERTS_GLB_INLINE void
-erts_no_atomic64_set(erts_no_atomic64_t *var, erts_aint64_t i)
-{
-    *var = i;
-}
-
-ERTS_GLB_INLINE erts_aint64_t
-erts_no_atomic64_read(erts_no_atomic64_t *var)
-{
-    return *var;
-}
-
-ERTS_GLB_INLINE erts_aint64_t
-erts_no_atomic64_inc_read(erts_no_atomic64_t *incp)
-{
-    return ++(*incp);
-}
-
-ERTS_GLB_INLINE erts_aint64_t
-erts_no_atomic64_dec_read(erts_no_atomic64_t *decp)
-{
-    return --(*decp);
-}
-
-ERTS_GLB_INLINE void
-erts_no_atomic64_inc(erts_no_atomic64_t *incp)
-{
-    ++(*incp);
-}
-
-ERTS_GLB_INLINE void
-erts_no_atomic64_dec(erts_no_atomic64_t *decp)
-{
-    --(*decp);
-}
-
-ERTS_GLB_INLINE erts_aint64_t
-erts_no_atomic64_add_read(erts_no_atomic64_t *addp, erts_aint64_t i)
-{
-    return *addp += i;
-}
-
-ERTS_GLB_INLINE void
-erts_no_atomic64_add(erts_no_atomic64_t *addp, erts_aint64_t i)
-{
-    *addp += i;
-}
-
-ERTS_GLB_INLINE erts_aint64_t
-erts_no_atomic64_read_bor(erts_no_atomic64_t *var, erts_aint64_t mask)
-{
-    erts_aint64_t old;
-    old = *var;
-    *var |= mask;
-    return old;
-}
-
-ERTS_GLB_INLINE erts_aint64_t
-erts_no_atomic64_read_band(erts_no_atomic64_t *var, erts_aint64_t mask)
-{
-    erts_aint64_t old;
-    old = *var;
-    *var &= mask;
-    return old;
-}
-
-ERTS_GLB_INLINE erts_aint64_t
-erts_no_atomic64_xchg(erts_no_atomic64_t *xchgp, erts_aint64_t new)
-{
-    erts_aint64_t old = *xchgp;
-    *xchgp = new;
-    return old;
-}
-
-ERTS_GLB_INLINE erts_aint64_t
-erts_no_atomic64_cmpxchg(erts_no_atomic64_t *xchgp,
-			 erts_aint64_t new,
-			 erts_aint64_t expected)
-{
-    erts_aint64_t old = *xchgp;
-    if (old == expected)
-        *xchgp = new;
-    return old;
-}
-
-ERTS_GLB_INLINE erts_aint64_t
-erts_no_atomic64_read_bset(erts_no_atomic64_t *var,
-			   erts_aint64_t mask,
-			   erts_aint64_t set)
-{
-    erts_aint64_t old = *var;
-    *var &= ~mask;
-    *var |= (mask & set);
-    return old;
-}
-
 /* spinlock */
 
 ERTS_GLB_INLINE void
 erts_spinlock_init(erts_spinlock_t *lock, char *name, Eterm extra, erts_lock_flags_t flags)
 {
-#ifdef USE_THREADS
     int res = ethr_spinlock_init(&lock->slck);
     if (res) {
         erts_thr_fatal_error(res, "init spinlock");
@@ -3029,13 +2095,11 @@ erts_spinlock_init(erts_spinlock_t *lock, char *name, Eterm extra, erts_lock_fla
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_init_ref_x(&lock->lcnt, name, extra, flags);
 #endif
-#endif /* USE_THREADS */
 }
 
 ERTS_GLB_INLINE void
 erts_spinlock_destroy(erts_spinlock_t *lock)
 {
-#ifdef USE_THREADS
     int res;
 
     ASSERT(!(lock->flags & ERTS_LOCK_FLAGS_PROPERTY_STATIC));
@@ -3058,15 +2122,11 @@ erts_spinlock_destroy(erts_spinlock_t *lock)
 #endif
 	    erts_thr_fatal_error(res, "destroy rwlock");
     }
-#else
-    (void)lock;
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_spin_unlock(erts_spinlock_t *lock)
 {
-#ifdef USE_THREADS
 #ifdef ERTS_ENABLE_LOCK_CHECK
     erts_lc_unlock(&lock->lc);
 #endif
@@ -3074,9 +2134,6 @@ erts_spin_unlock(erts_spinlock_t *lock)
     erts_lcnt_unlock(&lock->lcnt);
 #endif
     ethr_spin_unlock(&lock->slck);
-#else
-    (void)lock;
-#endif
 }
 
 ERTS_GLB_INLINE void
@@ -3086,7 +2143,6 @@ erts_spin_lock_x(erts_spinlock_t *lock, char *file, unsigned int line)
 erts_spin_lock(erts_spinlock_t *lock)
 #endif
 {
-#ifdef USE_THREADS
 #ifdef ERTS_ENABLE_LOCK_CHECK
 #ifdef ERTS_ENABLE_LOCK_POSITION
     erts_lc_lock_x(&lock->lc,file,line);
@@ -3101,15 +2157,12 @@ erts_spin_lock(erts_spinlock_t *lock)
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_lock_post_x(&lock->lcnt, file, line);
 #endif
-#else
-    (void)lock;
-#endif
 }
 
 ERTS_GLB_INLINE int
 erts_lc_spinlock_is_locked(erts_spinlock_t *lock)
 {
-#if defined(USE_THREADS) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     int res;
     erts_lc_lock_t lc = lock->lc;
     lc.flags = ERTS_LOCK_TYPE_SPINLOCK;
@@ -3126,7 +2179,6 @@ erts_lc_spinlock_is_locked(erts_spinlock_t *lock)
 ERTS_GLB_INLINE void
 erts_rwlock_init(erts_rwlock_t *lock, char *name, Eterm extra, erts_lock_flags_t flags)
 {
-#ifdef USE_THREADS
     int res = ethr_rwlock_init(&lock->rwlck);
     if (res) {
         erts_thr_fatal_error(res, "init rwlock");
@@ -3143,13 +2195,11 @@ erts_rwlock_init(erts_rwlock_t *lock, char *name, Eterm extra, erts_lock_flags_t
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_init_ref_x(&lock->lcnt, name, extra, flags);
 #endif
-#endif /* USE_THREADS */
 }
 
 ERTS_GLB_INLINE void
 erts_rwlock_destroy(erts_rwlock_t *lock)
 {
-#ifdef USE_THREADS
     int res;
 
     ASSERT(!(lock->flags & ERTS_LOCK_FLAGS_PROPERTY_STATIC));
@@ -3172,15 +2222,11 @@ erts_rwlock_destroy(erts_rwlock_t *lock)
 #endif
 	    erts_thr_fatal_error(res, "destroy rwlock");
     }
-#else
-    (void)lock;
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_read_unlock(erts_rwlock_t *lock)
 {
-#ifdef USE_THREADS
 #ifdef ERTS_ENABLE_LOCK_CHECK
     erts_lc_unlock_flg(&lock->lc, ERTS_LOCK_OPTIONS_READ);
 #endif
@@ -3188,9 +2234,6 @@ erts_read_unlock(erts_rwlock_t *lock)
     erts_lcnt_unlock_opt(&lock->lcnt, ERTS_LOCK_OPTIONS_READ);
 #endif
     ethr_read_unlock(&lock->rwlck);
-#else
-    (void)lock;
-#endif
 }
 
 ERTS_GLB_INLINE void
@@ -3200,7 +2243,6 @@ erts_read_lock_x(erts_rwlock_t *lock, char *file, unsigned int line)
 erts_read_lock(erts_rwlock_t *lock)
 #endif
 {
-#ifdef USE_THREADS
 #ifdef ERTS_ENABLE_LOCK_CHECK
 #ifdef ERTS_ENABLE_LOCK_POSITION
     erts_lc_lock_flg_x(&lock->lc, ERTS_LOCK_OPTIONS_READ,file,line);
@@ -3215,15 +2257,11 @@ erts_read_lock(erts_rwlock_t *lock)
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_lock_post_x(&lock->lcnt, file, line);
 #endif
-#else
-    (void)lock;
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_write_unlock(erts_rwlock_t *lock)
 {
-#ifdef USE_THREADS
 #ifdef ERTS_ENABLE_LOCK_CHECK
     erts_lc_unlock_flg(&lock->lc, ERTS_LOCK_OPTIONS_RDWR);
 #endif
@@ -3231,9 +2269,6 @@ erts_write_unlock(erts_rwlock_t *lock)
     erts_lcnt_unlock_opt(&lock->lcnt, ERTS_LOCK_OPTIONS_RDWR);
 #endif
     ethr_write_unlock(&lock->rwlck);
-#else
-    (void)lock;
-#endif
 }
 
 ERTS_GLB_INLINE void
@@ -3243,7 +2278,6 @@ erts_write_lock_x(erts_rwlock_t *lock, char *file, unsigned int line)
 erts_write_lock(erts_rwlock_t *lock)
 #endif
 {
-#ifdef USE_THREADS
 #ifdef ERTS_ENABLE_LOCK_CHECK
 #ifdef ERTS_ENABLE_LOCK_POSITION
     erts_lc_lock_flg_x(&lock->lc, ERTS_LOCK_OPTIONS_RDWR,file,line);
@@ -3258,15 +2292,12 @@ erts_write_lock(erts_rwlock_t *lock)
 #ifdef ERTS_ENABLE_LOCK_COUNT
     erts_lcnt_lock_post_x(&lock->lcnt, file, line);
 #endif
-#else
-    (void)lock;
-#endif
 }
 
 ERTS_GLB_INLINE int
 erts_lc_rwlock_is_rlocked(erts_rwlock_t *lock)
 {
-#if defined(USE_THREADS) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     int res;
     erts_lc_lock_t lc = lock->lc;
     lc.flags = ERTS_LOCK_TYPE_RWSPINLOCK;
@@ -3281,7 +2312,7 @@ erts_lc_rwlock_is_rlocked(erts_rwlock_t *lock)
 ERTS_GLB_INLINE int
 erts_lc_rwlock_is_rwlocked(erts_rwlock_t *lock)
 {
-#if defined(USE_THREADS) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     int res;
     erts_lc_lock_t lc = lock->lc;
     lc.flags = ERTS_LOCK_TYPE_RWSPINLOCK;
@@ -3296,125 +2327,90 @@ erts_lc_rwlock_is_rwlocked(erts_rwlock_t *lock)
 ERTS_GLB_INLINE void
 erts_tsd_key_create(erts_tsd_key_t *keyp, char *keyname)
 {
-#ifdef USE_THREADS
     int res = ethr_tsd_key_create(keyp, keyname);
     if (res)
 	erts_thr_fatal_error(res, "create thread specific data key");
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_tsd_key_delete(erts_tsd_key_t key)
 {
-#ifdef USE_THREADS
     int res = ethr_tsd_key_delete(key);
     if (res)
 	erts_thr_fatal_error(res, "delete thread specific data key");
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_tsd_set(erts_tsd_key_t key, void *value)
 {
-#ifdef USE_THREADS
     int res = ethr_tsd_set(key, value);
     if (res)
 	erts_thr_fatal_error(res, "set thread specific data");
-#endif
 }
 
 ERTS_GLB_INLINE void *
 erts_tsd_get(erts_tsd_key_t key)
 {
-#ifdef USE_THREADS
     return ethr_tsd_get(key);
-#else
-    return NULL;
-#endif
 }
 
 ERTS_GLB_INLINE erts_tse_t *erts_tse_fetch(void)
 {
-#ifdef USE_THREADS
     return (erts_tse_t *) ethr_get_ts_event();
-#else
-    return (erts_tse_t *) NULL;
-#endif
 }
 
 ERTS_GLB_INLINE void erts_tse_return(erts_tse_t *ep)
 {
-#ifdef USE_THREADS
     ethr_leave_ts_event(ep);
-#endif
 }
 
 ERTS_GLB_INLINE void erts_tse_prepare_timed(erts_tse_t *ep)
 {
-#ifdef USE_THREADS
     int res = ethr_event_prepare_timed(&((ethr_ts_event *) ep)->event);
     if (res != 0)
 	erts_thr_fatal_error(res, "prepare timed");
-#endif
 }
 
 ERTS_GLB_INLINE void erts_tse_set(erts_tse_t *ep)
 {
-#ifdef USE_THREADS
     ethr_event_set(&((ethr_ts_event *) ep)->event);
-#endif
 }
 
 ERTS_GLB_INLINE void erts_tse_reset(erts_tse_t *ep)
 {
-#ifdef USE_THREADS
     ethr_event_reset(&((ethr_ts_event *) ep)->event);
-#endif
 }
 
 ERTS_GLB_INLINE int erts_tse_wait(erts_tse_t *ep)
 {
-#ifdef USE_THREADS
     int res;
     ERTS_MSACC_PUSH_AND_SET_STATE(ERTS_MSACC_STATE_SLEEP);
     res = ethr_event_wait(&((ethr_ts_event *) ep)->event);
     ERTS_MSACC_POP_STATE();
     return res;
-#else
-    return ENOTSUP;
-#endif
 }
 
 ERTS_GLB_INLINE int erts_tse_swait(erts_tse_t *ep, int spincount)
 {
-#ifdef USE_THREADS
     int res;
     ERTS_MSACC_PUSH_AND_SET_STATE(ERTS_MSACC_STATE_SLEEP);
     res = ethr_event_swait(&((ethr_ts_event *) ep)->event, spincount);
     ERTS_MSACC_POP_STATE();
     return res;
-#else
-    return ENOTSUP;
-#endif
 }
 
 ERTS_GLB_INLINE int erts_tse_twait(erts_tse_t *ep, Sint64 tmo)
 {
-#ifdef USE_THREADS
     int res;
     ERTS_MSACC_PUSH_AND_SET_STATE(ERTS_MSACC_STATE_SLEEP);
     res = ethr_event_twait(&((ethr_ts_event *) ep)->event,
                            (ethr_sint64_t) tmo);
     ERTS_MSACC_POP_STATE();
     return res;
-#else
-    return ENOTSUP;
-#endif
 }
 
 ERTS_GLB_INLINE int erts_tse_stwait(erts_tse_t *ep, int spincount, Sint64 tmo)
 {
-#ifdef USE_THREADS
     int res;
     ERTS_MSACC_PUSH_AND_SET_STATE(ERTS_MSACC_STATE_SLEEP);
     res = ethr_event_stwait(&((ethr_ts_event *) ep)->event,
@@ -3422,49 +2418,34 @@ ERTS_GLB_INLINE int erts_tse_stwait(erts_tse_t *ep, int spincount, Sint64 tmo)
                             (ethr_sint64_t) tmo);
     ERTS_MSACC_POP_STATE();
     return res;
-#else
-    return ENOTSUP;
-#endif
 }
 
 ERTS_GLB_INLINE int erts_tse_is_tmp(erts_tse_t *ep)
 {
-#ifdef USE_THREADS
     return (ep->iflgs & ETHR_TS_EV_TMP) == ETHR_TS_EV_TMP;
-#else
-    return 0;
-#endif
 }
 
 ERTS_GLB_INLINE void erts_thr_set_main_status(int on, int no)
 {
-#ifdef USE_THREADS
     int res = ethr_set_main_thr_status(on, no);
     if (res != 0)
 	erts_thr_fatal_error(res, "set thread main status");
-#endif
 }
 
 ERTS_GLB_INLINE int erts_thr_get_main_status(void)
 {
-#ifdef USE_THREADS
     int main_status;
     int res = ethr_get_main_thr_status(&main_status);
     if (res != 0)
 	erts_thr_fatal_error(res, "get thread main status");
     return main_status;
-#else
-    return 1;
-#endif
 }
 
 ERTS_GLB_INLINE void erts_thr_yield(void)
 {
-#ifdef USE_THREADS
     int res = ETHR_YIELD();
     if (res != 0)
 	erts_thr_fatal_error(res, "yield");
-#endif    
 }
 
 
@@ -3472,34 +2453,28 @@ ERTS_GLB_INLINE void erts_thr_yield(void)
 
 ERTS_GLB_INLINE void
 erts_thr_kill(erts_tid_t tid, int sig) {
-#ifdef USE_THREADS
   int res = ethr_kill((ethr_tid)tid, sig);
   if (res)
     erts_thr_fatal_error(res, "killing thread");
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_thr_sigmask(int how, const sigset_t *set, sigset_t *oset)
 {
-#ifdef USE_THREADS
     int res = ethr_sigmask(how, set, oset);
     if (res)
 	erts_thr_fatal_error(res, "get or set signal mask");
-#endif
 }
 
 ERTS_GLB_INLINE void
 erts_thr_sigwait(const sigset_t *set, int *sig)
 {
-#ifdef USE_THREADS
     int res;
     do {
 	res = ethr_sigwait(set, sig);
     } while (res == EINTR);
     if (res)
 	erts_thr_fatal_error(res, "to wait for signal");
-#endif
 }
 
 #endif /* #ifdef HAVE_ETHR_SIG_FUNCS */
@@ -3507,37 +2482,3 @@ erts_thr_sigwait(const sigset_t *set, int *sig)
 #endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
 #endif /* #ifndef ERL_THREAD_H__ */
-
-#ifdef ERTS_UNDEF_DEPRECATED_ATOMICS
-
-/* Deprecated functions to replace */
-
-#undef erts_atomic_init
-#undef erts_atomic_set
-#undef erts_atomic_read
-#undef erts_atomic_inctest
-#undef erts_atomic_dectest
-#undef erts_atomic_inc
-#undef erts_atomic_dec
-#undef erts_atomic_addtest
-#undef erts_atomic_add
-#undef erts_atomic_xchg
-#undef erts_atomic_cmpxchg
-#undef erts_atomic_bor
-#undef erts_atomic_band
-
-#undef erts_atomic32_init
-#undef erts_atomic32_set
-#undef erts_atomic32_read
-#undef erts_atomic32_inctest
-#undef erts_atomic32_dectest
-#undef erts_atomic32_inc
-#undef erts_atomic32_dec
-#undef erts_atomic32_addtest
-#undef erts_atomic32_add
-#undef erts_atomic32_xchg
-#undef erts_atomic32_cmpxchg
-#undef erts_atomic32_bor
-#undef erts_atomic32_band
-
-#endif
diff --git a/erts/emulator/beam/erl_time_sup.c b/erts/emulator/beam/erl_time_sup.c
index 979c03fd43..f2e0900fec 100644
--- a/erts/emulator/beam/erl_time_sup.c
+++ b/erts/emulator/beam/erl_time_sup.c
@@ -36,11 +36,11 @@
 #include "erl_driver.h"
 #include "erl_nif.h"
  
-static erts_smp_mtx_t erts_get_time_mtx;
+static erts_mtx_t erts_get_time_mtx;
 
  /* used by erts_runtime_elapsed_both */
 typedef struct {
-    erts_smp_mtx_t mtx;
+    erts_mtx_t mtx;
     ErtsMonotonicTime user;
     ErtsMonotonicTime sys;
 } ErtsRunTimePrevData;
@@ -51,13 +51,13 @@ static union {
 } runtime_prev erts_align_attribute(ERTS_CACHE_LINE_SIZE);
 
 static union {
-    erts_smp_atomic64_t time;
-    char align__[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(erts_smp_atomic64_t))];
+    erts_atomic64_t time;
+    char align__[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(erts_atomic64_t))];
 } wall_clock_prev erts_align_attribute(ERTS_CACHE_LINE_SIZE);
 
 static union {
-    erts_smp_atomic64_t time;
-    char align__[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(erts_smp_atomic64_t))];
+    erts_atomic64_t time;
+    char align__[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(erts_atomic64_t))];
 } now_prev erts_align_attribute(ERTS_CACHE_LINE_SIZE);
 
 static ErtsMonitor *time_offset_monitors = NULL;
@@ -157,7 +157,7 @@ typedef struct {
 struct time_sup_infrequently_changed__ {
 #ifdef ERTS_HAVE_OS_MONOTONIC_TIME_SUPPORT
     struct {
-	erts_smp_rwmtx_t rwmtx;
+	erts_rwmtx_t rwmtx;
 	ErtsTWheelTimer timer;
 	ErtsMonotonicCorrectionData cdata;
     } parmon;
@@ -165,9 +165,9 @@ struct time_sup_infrequently_changed__ {
 #endif
     ErtsSystemTime sinit;
     ErtsMonotonicTime not_corrected_moffset;
-    erts_smp_atomic64_t offset;
+    erts_atomic64_t offset;
     ErtsMonotonicTime shadow_offset;
-    erts_smp_atomic32_t preliminary_offset;
+    erts_atomic32_t preliminary_offset;
 };
 
 struct time_sup_frequently_changed__ {
@@ -205,19 +205,19 @@ erts_get_approx_time(void)
 static ERTS_INLINE void
 init_time_offset(ErtsMonotonicTime offset)
 {
-    erts_smp_atomic64_init_nob(&time_sup.inf.c.offset, (erts_aint64_t) offset);
+    erts_atomic64_init_nob(&time_sup.inf.c.offset, (erts_aint64_t) offset);
 }
 
 static ERTS_INLINE void
 set_time_offset(ErtsMonotonicTime offset)
 {
-    erts_smp_atomic64_set_relb(&time_sup.inf.c.offset, (erts_aint64_t) offset);
+    erts_atomic64_set_relb(&time_sup.inf.c.offset, (erts_aint64_t) offset);
 }
 
 static ERTS_INLINE ErtsMonotonicTime
 get_time_offset(void)
 {
-    return (ErtsMonotonicTime) erts_smp_atomic64_read_acqb(&time_sup.inf.c.offset);
+    return (ErtsMonotonicTime) erts_atomic64_read_acqb(&time_sup.inf.c.offset);
 }
 
 static ERTS_INLINE void
@@ -298,7 +298,7 @@ read_corrected_time(int os_drift_corrected)
     ErtsMonotonicTime os_mtime;
     ErtsMonotonicCorrectionInstance ci;
 
-    erts_smp_rwmtx_rlock(&time_sup.inf.c.parmon.rwmtx);
+    erts_rwmtx_rlock(&time_sup.inf.c.parmon.rwmtx);
 
     os_mtime = erts_os_monotonic_time();
 
@@ -311,7 +311,7 @@ read_corrected_time(int os_drift_corrected)
 	ci = time_sup.inf.c.parmon.cdata.insts.prev;
     }
 
-    erts_smp_rwmtx_runlock(&time_sup.inf.c.parmon.rwmtx);
+    erts_rwmtx_runlock(&time_sup.inf.c.parmon.rwmtx);
 
     return calc_corrected_erl_mtime(os_mtime, &ci, NULL,
 				    os_drift_corrected);
@@ -389,13 +389,13 @@ check_time_correction(void *vesdp)
     int os_drift_corrected = time_sup.r.o.os_corrected_monotonic_time;
     int set_new_correction = 0, begin_short_intervals = 0;
 
-    erts_smp_rwmtx_rlock(&time_sup.inf.c.parmon.rwmtx);
+    erts_rwmtx_rlock(&time_sup.inf.c.parmon.rwmtx);
 
     erts_os_times(&os_mtime, &os_stime);
 
     ci = time_sup.inf.c.parmon.cdata.insts.curr;
 
-    erts_smp_rwmtx_runlock(&time_sup.inf.c.parmon.rwmtx);
+    erts_rwmtx_runlock(&time_sup.inf.c.parmon.rwmtx);
 
     if (os_mtime < ci.os_mtime)
 	erts_exit(ERTS_ABORT_EXIT,
@@ -410,7 +410,7 @@ check_time_correction(void *vesdp)
 
     if (time_sup.inf.c.shadow_offset) {
 	ERTS_TIME_ASSERT(time_sup.r.o.warp_mode == ERTS_SINGLE_TIME_WARP_MODE);
-	if (erts_smp_atomic32_read_nob(&time_sup.inf.c.preliminary_offset))
+	if (erts_atomic32_read_nob(&time_sup.inf.c.preliminary_offset))
 	    sdiff += time_sup.inf.c.shadow_offset;
 	else
 	    time_sup.inf.c.shadow_offset = 0;
@@ -433,7 +433,7 @@ check_time_correction(void *vesdp)
 	}
     }
     else if ((time_sup.r.o.warp_mode == ERTS_SINGLE_TIME_WARP_MODE
-	      && erts_smp_atomic32_read_nob(&time_sup.inf.c.preliminary_offset))
+	      && erts_atomic32_read_nob(&time_sup.inf.c.preliminary_offset))
 	     && (sdiff < -2*time_sup.r.o.adj.small_diff
 		 || 2*time_sup.r.o.adj.small_diff < sdiff)) {
 	/*
@@ -658,7 +658,7 @@ check_time_correction(void *vesdp)
 #endif
 
     if (set_new_correction) {
-	erts_smp_rwmtx_rwlock(&time_sup.inf.c.parmon.rwmtx);
+	erts_rwmtx_rwlock(&time_sup.inf.c.parmon.rwmtx);
 
 	os_mtime = erts_os_monotonic_time();
 
@@ -686,7 +686,7 @@ check_time_correction(void *vesdp)
 	time_sup.inf.c.parmon.cdata.insts.curr.os_mtime = os_mtime;
 	time_sup.inf.c.parmon.cdata.insts.curr.correction = new_correction;
 
-	erts_smp_rwmtx_rwunlock(&time_sup.inf.c.parmon.rwmtx);
+	erts_rwmtx_rwunlock(&time_sup.inf.c.parmon.rwmtx);
     }
 
     if (!esdp)
@@ -804,13 +804,13 @@ finalize_corrected_time_offset(ErtsSystemTime *stimep)
     ErtsMonotonicCorrectionInstance ci;
     int os_drift_corrected = time_sup.r.o.os_corrected_monotonic_time;
 
-    erts_smp_rwmtx_rlock(&time_sup.inf.c.parmon.rwmtx);
+    erts_rwmtx_rlock(&time_sup.inf.c.parmon.rwmtx);
 
     erts_os_times(&os_mtime, stimep);
 
     ci = time_sup.inf.c.parmon.cdata.insts.curr;
 
-    erts_smp_rwmtx_runlock(&time_sup.inf.c.parmon.rwmtx);
+    erts_rwmtx_runlock(&time_sup.inf.c.parmon.rwmtx);
 
     if (os_mtime < ci.os_mtime)
 	erts_exit(ERTS_ABORT_EXIT,
@@ -863,7 +863,7 @@ static ErtsMonotonicTime get_not_corrected_time(void)
 {
     ErtsMonotonicTime stime, mtime;
 
-    erts_smp_mtx_lock(&erts_get_time_mtx);
+    erts_mtx_lock(&erts_get_time_mtx);
 
     stime = erts_os_system_time();
 
@@ -889,7 +889,7 @@ static ErtsMonotonicTime get_not_corrected_time(void)
 
     ASSERT(stime == mtime + time_sup.inf.c.not_corrected_moffset);
 
-    erts_smp_mtx_unlock(&erts_get_time_mtx);
+    erts_mtx_unlock(&erts_get_time_mtx);
 
     return mtime;
 }
@@ -971,9 +971,9 @@ erts_init_time_sup(int time_correction, ErtsTimeWarpMode time_warp_mode)
 
     ASSERT(ERTS_MONOTONIC_TIME_MIN < ERTS_MONOTONIC_TIME_MAX);
 
-    erts_smp_mtx_init(&erts_get_time_mtx, "get_time", NIL,
+    erts_mtx_init(&erts_get_time_mtx, "get_time", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
-    erts_smp_mtx_init(&runtime_prev.data.mtx, "runtime", NIL,
+    erts_mtx_init(&runtime_prev.data.mtx, "runtime", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
     runtime_prev.data.user = 0;
     runtime_prev.data.sys = 0;
@@ -982,9 +982,9 @@ erts_init_time_sup(int time_correction, ErtsTimeWarpMode time_warp_mode)
     time_sup.r.o.warp_mode = time_warp_mode;
  
     if (time_warp_mode == ERTS_SINGLE_TIME_WARP_MODE)
-	erts_smp_atomic32_init_nob(&time_sup.inf.c.preliminary_offset, 1);
+	erts_atomic32_init_nob(&time_sup.inf.c.preliminary_offset, 1);
     else
-	erts_smp_atomic32_init_nob(&time_sup.inf.c.preliminary_offset, 0);
+	erts_atomic32_init_nob(&time_sup.inf.c.preliminary_offset, 0);
     time_sup.inf.c.shadow_offset = 0;
 
 #if !ERTS_COMPILE_TIME_MONOTONIC_TIME_UNIT
@@ -1128,7 +1128,7 @@ erts_init_time_sup(int time_correction, ErtsTimeWarpMode time_warp_mode)
 
     if (time_sup.r.o.correction) {
 	ErtsMonotonicCorrectionData *cdatap;
-	erts_smp_rwmtx_opt_t rwmtx_opts = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
+	erts_rwmtx_opt_t rwmtx_opts = ERTS_RWMTX_OPT_DEFAULT_INITER;
 	ErtsMonotonicTime offset;
 	erts_os_times(&time_sup.inf.c.minit,
 		      &time_sup.inf.c.sinit);
@@ -1138,10 +1138,10 @@ erts_init_time_sup(int time_correction, ErtsTimeWarpMode time_warp_mode)
 	offset -= ERTS_MONOTONIC_BEGIN;
 	init_time_offset(offset);
 
-	rwmtx_opts.type = ERTS_SMP_RWMTX_TYPE_EXTREMELY_FREQUENT_READ;
-	rwmtx_opts.lived = ERTS_SMP_RWMTX_LONG_LIVED;
+	rwmtx_opts.type = ERTS_RWMTX_TYPE_EXTREMELY_FREQUENT_READ;
+	rwmtx_opts.lived = ERTS_RWMTX_LONG_LIVED;
 
-        erts_smp_rwmtx_init_opt(&time_sup.inf.c.parmon.rwmtx, &rwmtx_opts,
+        erts_rwmtx_init_opt(&time_sup.inf.c.parmon.rwmtx, &rwmtx_opts,
             "get_corrected_time", NIL,
             ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
 
@@ -1176,10 +1176,10 @@ erts_init_time_sup(int time_correction, ErtsTimeWarpMode time_warp_mode)
 	time_sup.f.c.last_not_corrected_time = 0;
     }
 
-    erts_smp_atomic64_init_nob(&wall_clock_prev.time,
-                               (erts_aint64_t) 0);
+    erts_atomic64_init_nob(&wall_clock_prev.time,
+                           (erts_aint64_t) 0);
 
-    erts_smp_atomic64_init_nob(
+    erts_atomic64_init_nob(
         &now_prev.time,
         (erts_aint64_t) ERTS_MONOTONIC_TO_USEC(get_time_offset()));
 
@@ -1223,7 +1223,7 @@ ErtsTimeOffsetState erts_time_offset_state(void)
     case ERTS_NO_TIME_WARP_MODE:
 	return ERTS_TIME_OFFSET_FINAL;
     case ERTS_SINGLE_TIME_WARP_MODE:
-	if (erts_smp_atomic32_read_nob(&time_sup.inf.c.preliminary_offset))
+	if (erts_atomic32_read_nob(&time_sup.inf.c.preliminary_offset))
 	    return ERTS_TIME_OFFSET_PRELIMINARY;
 	return ERTS_TIME_OFFSET_FINAL;
     case ERTS_MULTI_TIME_WARP_MODE:
@@ -1256,9 +1256,9 @@ erts_finalize_time_offset(void)
     case ERTS_SINGLE_TIME_WARP_MODE: {
 	ErtsTimeOffsetState res = ERTS_TIME_OFFSET_FINAL;
 
-	erts_smp_mtx_lock(&erts_get_time_mtx);
+	erts_mtx_lock(&erts_get_time_mtx);
 
-	if (erts_smp_atomic32_read_nob(&time_sup.inf.c.preliminary_offset)) {
+	if (erts_atomic32_read_nob(&time_sup.inf.c.preliminary_offset)) {
 	    ErtsMonotonicTime mtime, new_offset;
 
 #ifdef ERTS_HAVE_OS_MONOTONIC_TIME_SUPPORT
@@ -1295,11 +1295,11 @@ erts_finalize_time_offset(void)
 	    set_time_offset(new_offset);
 	    schedule_send_time_offset_changed_notifications(new_offset);
 
-	    erts_smp_atomic32_set_nob(&time_sup.inf.c.preliminary_offset, 0);
+	    erts_atomic32_set_nob(&time_sup.inf.c.preliminary_offset, 0);
 	    res = ERTS_TIME_OFFSET_PRELIMINARY;
 	}
 
-	erts_smp_mtx_unlock(&erts_get_time_mtx);
+	erts_mtx_unlock(&erts_get_time_mtx);
 
 	return res;
     }
@@ -1358,14 +1358,14 @@ erts_runtime_elapsed_both(ErtsMonotonicTime *ms_user, ErtsMonotonicTime *ms_sys,
 
     if (ms_user_diff || ms_sys_diff) {
  
-        erts_smp_mtx_lock(&runtime_prev.data.mtx);
+        erts_mtx_lock(&runtime_prev.data.mtx);
 
         prev_user = runtime_prev.data.user;
         prev_sys = runtime_prev.data.sys;
         runtime_prev.data.user = user;
         runtime_prev.data.sys = sys;
 
-        erts_smp_mtx_unlock(&runtime_prev.data.mtx);
+        erts_mtx_unlock(&runtime_prev.data.mtx);
 
         if (ms_user_diff)
             *ms_user_diff = user - prev_user;
@@ -1394,8 +1394,8 @@ erts_wall_clock_elapsed_both(ErtsMonotonicTime *ms_total, ErtsMonotonicTime *ms_
         ErtsMonotonicTime prev;
 
         prev = ((ErtsMonotonicTime)
-                erts_smp_atomic64_xchg_mb(&wall_clock_prev.time,
-                                          (erts_aint64_t) elapsed));
+                erts_atomic64_xchg_mb(&wall_clock_prev.time,
+                                      (erts_aint64_t) elapsed));
 
         *ms_diff = elapsed - prev;
     }
@@ -1784,15 +1784,15 @@ get_now(Uint* megasec, Uint* sec, Uint* microsec)
     now = ERTS_MONOTONIC_TO_USEC(mtime + time_offset);
 
     /* Make sure now time is later than last time */
-    prev = erts_smp_atomic64_read_nob(&now_prev.time);
+    prev = erts_atomic64_read_nob(&now_prev.time);
     while (1) {
         ErtsMonotonicTime act;
         if (now <= prev)
             now = prev + 1;
         act = ((ErtsMonotonicTime)
-               erts_smp_atomic64_cmpxchg_mb(&now_prev.time,
-                                            (erts_aint64_t) now,
-                                            (erts_aint64_t) prev));
+               erts_atomic64_cmpxchg_mb(&now_prev.time,
+                                        (erts_aint64_t) now,
+                                        (erts_aint64_t) prev));
         if (act == prev)
             break;
         prev = act;
@@ -1883,10 +1883,10 @@ void erts_get_now_cpu(Uint* megasec, Uint* sec, Uint* microsec) {
 void
 erts_monitor_time_offset(Eterm id, Eterm ref)
 {
-    erts_smp_mtx_lock(&erts_get_time_mtx);
+    erts_mtx_lock(&erts_get_time_mtx);
     erts_add_monitor(&time_offset_monitors, MON_TIME_OFFSET, ref, id, NIL);
     no_time_offset_monitors++;
-    erts_smp_mtx_unlock(&erts_get_time_mtx);
+    erts_mtx_unlock(&erts_get_time_mtx);
 }
 
 int
@@ -1895,7 +1895,7 @@ erts_demonitor_time_offset(Eterm ref)
     int res;
     ErtsMonitor *mon;
     ASSERT(is_internal_ref(ref));
-    erts_smp_mtx_lock(&erts_get_time_mtx);
+    erts_mtx_lock(&erts_get_time_mtx);
     if (is_internal_ordinary_ref(ref))
         mon = erts_remove_monitor(&time_offset_monitors, ref);
     else
@@ -1907,7 +1907,7 @@ erts_demonitor_time_offset(Eterm ref)
 	no_time_offset_monitors--;
 	res = 1;
     }
-    erts_smp_mtx_unlock(&erts_get_time_mtx);
+    erts_mtx_unlock(&erts_get_time_mtx);
     if (res)
 	erts_destroy_monitor(mon);
     return res;
@@ -1965,7 +1965,7 @@ send_time_offset_changed_notifications(void *new_offsetp)
 #endif
     new_offset -= ERTS_MONOTONIC_OFFSET_NATIVE;
 
-    erts_smp_mtx_lock(&erts_get_time_mtx);
+    erts_mtx_lock(&erts_get_time_mtx);
 
     no_monitors = no_time_offset_monitors;
     if (no_monitors) {
@@ -1990,7 +1990,7 @@ send_time_offset_changed_notifications(void *new_offsetp)
 	ASSERT(cntxt.ix == no_monitors);
     }
 
-    erts_smp_mtx_unlock(&erts_get_time_mtx);
+    erts_mtx_unlock(&erts_get_time_mtx);
 
     if (no_monitors) {
 	Eterm *hp, *patch_refp, new_offset_term, message_template;
@@ -2023,7 +2023,7 @@ send_time_offset_changed_notifications(void *new_offsetp)
 	    if (rp) {
 		Eterm ref = to_mon_info[mix].ref;
 		ErtsProcLocks rp_locks = ERTS_PROC_LOCK_LINK;
-		erts_smp_proc_lock(rp, ERTS_PROC_LOCK_LINK);
+		erts_proc_lock(rp, ERTS_PROC_LOCK_LINK);
 		if (erts_lookup_monitor(ERTS_P_MONITORS(rp), ref)) {
 		    ErtsMessage *mp;
 		    ErlOffHeap *ohp;
@@ -2036,7 +2036,7 @@ send_time_offset_changed_notifications(void *new_offsetp)
 		    message = copy_struct(message_template, hsz, &hp, ohp);
 		    erts_queue_message(rp, rp_locks, mp, message, am_clock_service);
 		}
-		erts_smp_proc_unlock(rp, rp_locks);
+		erts_proc_unlock(rp, rp_locks);
 	    }
 	}
 
diff --git a/erts/emulator/beam/erl_trace.c b/erts/emulator/beam/erl_trace.c
index db7d0ac449..4b996d8fc2 100644
--- a/erts/emulator/beam/erl_trace.c
+++ b/erts/emulator/beam/erl_trace.c
@@ -77,8 +77,8 @@ static Eterm system_profile;
 int erts_cpu_timestamp;
 #endif
 
-static erts_smp_mtx_t smq_mtx;
-static erts_smp_rwmtx_t sys_trace_rwmtx;
+static erts_mtx_t smq_mtx;
+static erts_rwmtx_t sys_trace_rwmtx;
 
 enum ErtsSysMsgType {
     SYS_MSG_TYPE_UNDEFINED,
@@ -237,7 +237,6 @@ write_timestamp(ErtsTraceTimeStamp *tsp, Eterm **hpp)
     }
 }
 
-#ifdef ERTS_SMP
 
 static ERTS_INLINE Uint
 patch_ts_size(int ts_type)
@@ -257,7 +256,6 @@ patch_ts_size(int ts_type)
 	return 0;
     }
 }
-#endif /* ERTS_SMP */
 
 /*
  * Write a timestamp. The timestamp MUST be the last
@@ -298,18 +296,11 @@ write_ts(int ts_type, Eterm *hp, ErlHeapFragment *bp, Process *tracer)
     if (shrink) {
 	if (bp)
 	    bp->used_size -= shrink;
-#ifndef ERTS_SMP
-	else if (tracer) {
-	    Eterm *endp = ts_hp + shrink;
-	    HRelease(tracer, endp, ts_hp);
-	}
-#endif
     }
 
     return res;
 }
 
-#ifdef ERTS_SMP
 static void enqueue_sys_msg_unlocked(enum ErtsSysMsgType type,
 				     Eterm from,
 				     Eterm to,
@@ -321,7 +312,6 @@ static void enqueue_sys_msg(enum ErtsSysMsgType type,
 			    Eterm msg,
 			    ErlHeapFragment *bp);
 static void init_sys_msg_dispatcher(void);
-#endif
 
 static void init_tracer_nif(void);
 static int tracer_cmp_fun(void*, void*);
@@ -332,11 +322,11 @@ static void tracer_free_fun(void*);
 typedef struct ErtsTracerNif_ ErtsTracerNif;
 
 void erts_init_trace(void) {
-    erts_smp_rwmtx_opt_t rwmtx_opts = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
-    rwmtx_opts.type = ERTS_SMP_RWMTX_TYPE_EXTREMELY_FREQUENT_READ;
-    rwmtx_opts.lived = ERTS_SMP_RWMTX_LONG_LIVED;
+    erts_rwmtx_opt_t rwmtx_opts = ERTS_RWMTX_OPT_DEFAULT_INITER;
+    rwmtx_opts.type = ERTS_RWMTX_TYPE_EXTREMELY_FREQUENT_READ;
+    rwmtx_opts.lived = ERTS_RWMTX_LONG_LIVED;
 
-    erts_smp_rwmtx_init_opt(&sys_trace_rwmtx, &rwmtx_opts, "sys_tracers", NIL,
+    erts_rwmtx_init_opt(&sys_trace_rwmtx, &rwmtx_opts, "sys_tracers", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_DEBUG);
 
 #ifdef HAVE_ERTS_NOW_CPU
@@ -350,9 +340,7 @@ void erts_init_trace(void) {
     default_port_trace_flags = F_INITIAL_TRACE_FLAGS;
     default_port_tracer = erts_tracer_nil;
     system_seq_tracer = erts_tracer_nil;
-#ifdef ERTS_SMP
     init_sys_msg_dispatcher();
-#endif
     init_tracer_nif();
 }
 
@@ -412,43 +400,35 @@ static Uint active_sched;
 void
 erts_system_profile_setup_active_schedulers(void)
 {
-    ERTS_SMP_LC_ASSERT(erts_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
     active_sched = erts_active_schedulers();
 }
 
 static void
 exiting_reset(Eterm exiting)
 {
-    erts_smp_rwmtx_rwlock(&sys_trace_rwmtx);
+    erts_rwmtx_rwlock(&sys_trace_rwmtx);
     if (exiting == system_monitor) {
-#ifdef ERTS_SMP
 	system_monitor = NIL;
 	/* Let the trace message dispatcher clear flags, etc */
-#else
-	erts_system_monitor_clear(NULL);
-#endif
     }
     if (exiting == system_profile) {
-#ifdef ERTS_SMP
 	system_profile = NIL;
 	/* Let the trace message dispatcher clear flags, etc */
-#else
-	erts_system_profile_clear(NULL);
-#endif
     }
-    erts_smp_rwmtx_rwunlock(&sys_trace_rwmtx);
+    erts_rwmtx_rwunlock(&sys_trace_rwmtx);
 }
 
 void
 erts_trace_check_exiting(Eterm exiting)
 {
     int reset = 0;
-    erts_smp_rwmtx_rlock(&sys_trace_rwmtx);
+    erts_rwmtx_rlock(&sys_trace_rwmtx);
     if (exiting == system_monitor)
 	reset = 1;
     else if (exiting == system_profile)
 	reset = 1;
-    erts_smp_rwmtx_runlock(&sys_trace_rwmtx);
+    erts_rwmtx_runlock(&sys_trace_rwmtx);
     if (reset)
 	exiting_reset(exiting);
 }
@@ -468,7 +448,7 @@ erts_set_system_seq_tracer(Process *c_p, ErtsProcLocks c_p_locks, ErtsTracer new
         }
     }
 
-    erts_smp_rwmtx_rwlock(&sys_trace_rwmtx);
+    erts_rwmtx_rwlock(&sys_trace_rwmtx);
     old = system_seq_tracer;
     system_seq_tracer = erts_tracer_nil;
     erts_tracer_update(&system_seq_tracer, new);
@@ -476,7 +456,7 @@ erts_set_system_seq_tracer(Process *c_p, ErtsProcLocks c_p_locks, ErtsTracer new
 #ifdef DEBUG_PRINTOUTS
     erts_fprintf(stderr, "set seq tracer new=%T old=%T\n", new, old);
 #endif
-    erts_smp_rwmtx_rwunlock(&sys_trace_rwmtx);
+    erts_rwmtx_rwunlock(&sys_trace_rwmtx);
     return old;
 }
 
@@ -484,12 +464,12 @@ ErtsTracer
 erts_get_system_seq_tracer(void)
 {
     ErtsTracer st;
-    erts_smp_rwmtx_rlock(&sys_trace_rwmtx);
+    erts_rwmtx_rlock(&sys_trace_rwmtx);
     st = system_seq_tracer;
 #ifdef DEBUG_PRINTOUTS
     erts_fprintf(stderr, "get seq tracer %T\n", st);
 #endif
-    erts_smp_rwmtx_runlock(&sys_trace_rwmtx);
+    erts_rwmtx_runlock(&sys_trace_rwmtx);
 
     if (st != erts_tracer_nil &&
         call_enabled_tracer(st, NULL, TRACE_FUN_ENABLED,
@@ -522,8 +502,8 @@ get_default_tracing(Uint *flagsp, ErtsTracer *tracerp,
             ErtsTracer curr_default_tracer = *default_tracer;
             if (tracerp) {
                 /* we only have a rlock, so we have to unlock and then rwlock */
-                erts_smp_rwmtx_runlock(&sys_trace_rwmtx);
-                erts_smp_rwmtx_rwlock(&sys_trace_rwmtx);
+                erts_rwmtx_runlock(&sys_trace_rwmtx);
+                erts_rwmtx_rwlock(&sys_trace_rwmtx);
             }
             /* check if someone else changed default tracer
                while we got the write lock, if so we don't do
@@ -533,8 +513,8 @@ get_default_tracing(Uint *flagsp, ErtsTracer *tracerp,
                 ERTS_TRACER_CLEAR(default_tracer);
             }
             if (tracerp) {
-                erts_smp_rwmtx_rwunlock(&sys_trace_rwmtx);
-                erts_smp_rwmtx_rlock(&sys_trace_rwmtx);
+                erts_rwmtx_rwunlock(&sys_trace_rwmtx);
+                erts_rwmtx_rlock(&sys_trace_rwmtx);
             }
         }
         }
@@ -567,81 +547,81 @@ void
 erts_change_default_proc_tracing(int setflags, Uint flagsp,
                                  const ErtsTracer tracer)
 {
-    erts_smp_rwmtx_rwlock(&sys_trace_rwmtx);
+    erts_rwmtx_rwlock(&sys_trace_rwmtx);
     erts_change_default_tracing(
         setflags, flagsp, tracer,
         &default_proc_trace_flags,
         &default_proc_tracer);
-    erts_smp_rwmtx_rwunlock(&sys_trace_rwmtx);
+    erts_rwmtx_rwunlock(&sys_trace_rwmtx);
 }
 
 void
 erts_change_default_port_tracing(int setflags, Uint flagsp,
                                  const ErtsTracer tracer)
 {
-    erts_smp_rwmtx_rwlock(&sys_trace_rwmtx);
+    erts_rwmtx_rwlock(&sys_trace_rwmtx);
     erts_change_default_tracing(
         setflags, flagsp, tracer,
         &default_port_trace_flags,
         &default_port_tracer);
-    erts_smp_rwmtx_rwunlock(&sys_trace_rwmtx);
+    erts_rwmtx_rwunlock(&sys_trace_rwmtx);
 }
 
 void
 erts_get_default_proc_tracing(Uint *flagsp, ErtsTracer *tracerp)
 {
-    erts_smp_rwmtx_rlock(&sys_trace_rwmtx);
+    erts_rwmtx_rlock(&sys_trace_rwmtx);
     *tracerp = erts_tracer_nil; /* initialize */
     get_default_tracing(
         flagsp, tracerp,
         &default_proc_trace_flags,
         &default_proc_tracer);
-    erts_smp_rwmtx_runlock(&sys_trace_rwmtx);
+    erts_rwmtx_runlock(&sys_trace_rwmtx);
 }
 
 void
 erts_get_default_port_tracing(Uint *flagsp, ErtsTracer *tracerp)
 {
-    erts_smp_rwmtx_rlock(&sys_trace_rwmtx);
+    erts_rwmtx_rlock(&sys_trace_rwmtx);
     *tracerp = erts_tracer_nil; /* initialize */
     get_default_tracing(
         flagsp, tracerp,
         &default_port_trace_flags,
         &default_port_tracer);
-    erts_smp_rwmtx_runlock(&sys_trace_rwmtx);
+    erts_rwmtx_runlock(&sys_trace_rwmtx);
 }
 
 void
 erts_set_system_monitor(Eterm monitor)
 {
-    erts_smp_rwmtx_rwlock(&sys_trace_rwmtx);
+    erts_rwmtx_rwlock(&sys_trace_rwmtx);
     system_monitor = monitor;
-    erts_smp_rwmtx_rwunlock(&sys_trace_rwmtx);
+    erts_rwmtx_rwunlock(&sys_trace_rwmtx);
 }
 
 Eterm
 erts_get_system_monitor(void)
 {
     Eterm monitor;
-    erts_smp_rwmtx_rlock(&sys_trace_rwmtx);
+    erts_rwmtx_rlock(&sys_trace_rwmtx);
     monitor = system_monitor;
-    erts_smp_rwmtx_runlock(&sys_trace_rwmtx);
+    erts_rwmtx_runlock(&sys_trace_rwmtx);
     return monitor;
 }
 
 /* Performance monitoring */
 void erts_set_system_profile(Eterm profile) {
-    erts_smp_rwmtx_rwlock(&sys_trace_rwmtx);
+    erts_rwmtx_rwlock(&sys_trace_rwmtx);
     system_profile = profile;
-    erts_smp_rwmtx_rwunlock(&sys_trace_rwmtx);
+    erts_rwmtx_rwunlock(&sys_trace_rwmtx);
 }
 
 Eterm
 erts_get_system_profile(void) {
     Eterm profile;
-    erts_smp_rwmtx_rlock(&sys_trace_rwmtx);
+    erts_rwmtx_rlock(&sys_trace_rwmtx);
     profile = system_profile;
-    erts_smp_rwmtx_runlock(&sys_trace_rwmtx);
+    erts_rwmtx_runlock(&sys_trace_rwmtx);
     return profile;
 }
 
@@ -679,71 +659,11 @@ write_sys_msg_to_port(Eterm unused_to,
 	erts_exit(ERTS_ERROR_EXIT, "Internal error in do_send_to_port: %d\n", ptr-buffer);
     }
 
-#ifndef ERTS_SMP
-    if (!INVALID_TRACER_PORT(trace_port, trace_port->common.id))
-#endif
 	erts_raw_port_command(trace_port, buffer, ptr-buffer);
 
     erts_free(ERTS_ALC_T_TMP, (void *) buffer);
 }
 
-#ifndef ERTS_SMP
-/* Profile send
- * Checks if profiler is port or process
- * Eterm msg is local, need copying.
- */
-
-static void 
-profile_send(Eterm from, Eterm message) {
-    Uint sz = 0;
-    Uint *hp = NULL;
-    Eterm msg = NIL;
-    Process *profile_p = NULL;
-
-    Eterm profiler = erts_get_system_profile();
-
-    /* do not profile profiler pid */
-    if (from == profiler) return;
-
-    if (is_internal_port(profiler)) {
-    	Port *profiler_port = NULL;
-
-	/* not smp */
-
-	profiler_port = erts_id2port_sflgs(profiler,
-					   NULL,
-					   0,
-					   ERTS_PORT_SFLGS_INVALID_TRACER_LOOKUP);
-	if (profiler_port) {
-	    write_sys_msg_to_port(profiler,
-                                  profiler_port,
-                                  NIL, /* or current process->common.id */
-                                  SYS_MSG_TYPE_SYSPROF,
-                                  message);
-	    erts_port_release(profiler_port);
-	}
-    	
-    } else {
-	ErtsMessage *mp;
-	ASSERT(is_internal_pid(profiler));
-        
-	profile_p = erts_proc_lookup(profiler);
-
-	if (!profile_p)
-	    return;
-
-	sz = size_object(message);
-	mp = erts_alloc_message(sz, &hp);
-	if (sz == 0)
-	    msg = message;
-	else
-	    msg = copy_struct(message, sz, &hp, &mp->hfrag.off_heap);
-
-        erts_queue_message(profile_p, 0, mp, msg, from);
-    }
-}
-
-#endif
 
 static void
 trace_sched_aux(Process *p, ErtsProcLocks locks, Eterm what)
@@ -815,9 +735,7 @@ trace_send(Process *p, Eterm to, Eterm msg)
     ErtsTracerNif *tnif = NULL;
     ErtsTracingEvent* te;
     Eterm pam_result;
-#ifdef ERTS_SMP
     ErtsThrPrgrDelayHandle dhndl;
-#endif
 
     ASSERT(ARE_TRACE_FLAGS_ON(p, F_TRACE_SEND));
 
@@ -842,9 +760,7 @@ trace_send(Process *p, Eterm to, Eterm msg)
     } else
         pam_result = am_true;
 
-#ifdef ERTS_SMP
     dhndl = erts_thr_progress_unmanaged_delay();
-#endif
 
     if (is_internal_pid(to)) {
 	if (!erts_proc_lookup(to))
@@ -862,9 +778,7 @@ trace_send(Process *p, Eterm to, Eterm msg)
                            operation, msg, to, pam_result);
     }
 
-#ifdef ERTS_SMP
     erts_thr_progress_unmanaged_continue(dhndl);
-#endif
 
     erts_match_set_release_result_trace(p, pam_result);
 }
@@ -1179,7 +1093,7 @@ erts_call_trace(Process* p, ErtsCodeInfo *info, Binary *match_spec,
     Eterm transformed_args[MAX_ARG];
     ErtsTracer pre_ms_tracer = erts_tracer_nil;
 
-    ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(p) & ERTS_PROC_LOCK_MAIN);
+    ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(p) & ERTS_PROC_LOCK_MAIN);
 
     ASSERT(tracer);
     if (ERTS_TRACER_COMPARE(*tracer, erts_tracer_true)) {
@@ -1467,21 +1381,11 @@ monitor_long_schedule_proc(Process *p, ErtsCodeMFA *in_fp,
 {
     ErlHeapFragment *bp;
     ErlOffHeap *off_heap;
-#ifndef ERTS_SMP
-    Process *monitor_p;
-#endif
     Uint hsz;
     Eterm *hp, list, in_mfa = am_undefined, out_mfa = am_undefined;
     Eterm in_tpl, out_tpl, tmo_tpl, tmo, msg;
  
 
-#ifndef ERTS_SMP
-    ASSERT(is_internal_pid(system_monitor));
-    monitor_p = erts_proc_lookup(system_monitor);
-    if (!monitor_p || p == monitor_p) {
-	return;
-    }
-#endif
     /* 
      * Size: {monitor, pid, long_schedule, [{timeout, T}, {in, {M,F,A}},{out,{M,F,A}}]} ->
      * 5 (top tuple of 4), (3 (elements) * 2 (cons)) + 3 (timeout tuple of 2) + size of Timeout +
@@ -1517,36 +1421,18 @@ monitor_long_schedule_proc(Process *p, ErtsCodeMFA *in_fp,
     hp += 2;
     msg = TUPLE4(hp, am_monitor, p->common.id, am_long_schedule, list);
     hp += 5;
-#ifdef ERTS_SMP
     enqueue_sys_msg(SYS_MSG_TYPE_SYSMON, p->common.id, NIL, msg, bp);
-#else
-    {
-	ErtsMessage *mp = erts_alloc_message(0, NULL);
-	mp->data.heap_frag = bp;
-	erts_queue_message(monitor_p, 0, mp, msg, am_system);
-    }
-#endif
 }
 void 
 monitor_long_schedule_port(Port *pp, ErtsPortTaskType type, Uint time)
 {
     ErlHeapFragment *bp;
     ErlOffHeap *off_heap;
-#ifndef ERTS_SMP
-    Process *monitor_p;
-#endif
     Uint hsz;
     Eterm *hp, list, op;
     Eterm op_tpl, tmo_tpl, tmo, msg;
  
 
-#ifndef ERTS_SMP
-    ASSERT(is_internal_pid(system_monitor));
-    monitor_p = erts_proc_lookup(system_monitor);
-    if (!monitor_p) {
-	return;
-    }
-#endif
     /* 
      * Size: {monitor, port, long_schedule, [{timeout, T}, {op, Operation}]} ->
      * 5 (top tuple of 4), (2 (elements) * 2 (cons)) + 3 (timeout tuple of 2) 
@@ -1563,7 +1449,6 @@ monitor_long_schedule_port(Port *pp, ErtsPortTaskType type, Uint time)
     case ERTS_PORT_TASK_TIMEOUT: op = am_timeout; break;
     case ERTS_PORT_TASK_INPUT: op = am_input; break;
     case ERTS_PORT_TASK_OUTPUT: op = am_output; break;
-    case ERTS_PORT_TASK_EVENT: op = am_event; break;
     case ERTS_PORT_TASK_DIST_CMD: op = am_dist_cmd; break;
     default: op = am_undefined; break;
     }
@@ -1582,24 +1467,13 @@ monitor_long_schedule_port(Port *pp, ErtsPortTaskType type, Uint time)
     hp += 2;
     msg = TUPLE4(hp, am_monitor, pp->common.id, am_long_schedule, list);
     hp += 5;
-#ifdef ERTS_SMP
     enqueue_sys_msg(SYS_MSG_TYPE_SYSMON, pp->common.id, NIL, msg, bp);
-#else
-    {
-	ErtsMessage *mp = erts_alloc_message(0, NULL);
-	mp->data.heap_frag = bp;
-	erts_queue_message(monitor_p, 0, mp, msg, am_system);
-    }
-#endif
 }
 
 void
 monitor_long_gc(Process *p, Uint time) {
     ErlHeapFragment *bp;
     ErlOffHeap *off_heap;
-#ifndef ERTS_SMP
-    Process *monitor_p;
-#endif
     Uint hsz;
     Eterm *hp, list, msg;
     Eterm tags[] = {
@@ -1624,12 +1498,6 @@ monitor_long_gc(Process *p, Uint time) {
     Eterm *hp_end;
 #endif
 	
-#ifndef ERTS_SMP
-    ASSERT(is_internal_pid(system_monitor));
-    monitor_p = erts_proc_lookup(system_monitor);
-    if (!monitor_p || p == monitor_p)
-	return;
-#endif
 
     hsz = 0;
     (void) erts_bld_atom_uword_2tup_list(NULL,
@@ -1657,24 +1525,13 @@ monitor_long_gc(Process *p, Uint time) {
     ASSERT(hp == hp_end);
 #endif
 
-#ifdef ERTS_SMP
     enqueue_sys_msg(SYS_MSG_TYPE_SYSMON, p->common.id, NIL, msg, bp);
-#else
-    {
-	ErtsMessage *mp = erts_alloc_message(0, NULL);
-	mp->data.heap_frag = bp;
-	erts_queue_message(monitor_p, 0, mp, msg, am_system);
-    }
-#endif
 }
 
 void
 monitor_large_heap(Process *p) {
     ErlHeapFragment *bp;
     ErlOffHeap *off_heap;
-#ifndef ERTS_SMP
-    Process *monitor_p;
-#endif
     Uint hsz;
     Eterm *hp, list, msg;
     Eterm tags[] = {
@@ -1698,13 +1555,6 @@ monitor_large_heap(Process *p) {
 #endif
 
 
-#ifndef ERTS_SMP 
-    ASSERT(is_internal_pid(system_monitor));
-    monitor_p = erts_proc_lookup(system_monitor);
-    if (!monitor_p || p == monitor_p) {
-	return;
-    }
-#endif
 
     hsz = 0;
     (void) erts_bld_atom_uword_2tup_list(NULL,
@@ -1732,47 +1582,22 @@ monitor_large_heap(Process *p) {
     ASSERT(hp == hp_end);
 #endif
 
-#ifdef ERTS_SMP
     enqueue_sys_msg(SYS_MSG_TYPE_SYSMON, p->common.id, NIL, msg, bp);
-#else
-    {
-	ErtsMessage *mp = erts_alloc_message(0, NULL);
-	mp->data.heap_frag = bp;
-	erts_queue_message(monitor_p, 0, mp, msg, am_system);
-    }
-#endif
 }
 
 void
 monitor_generic(Process *p, Eterm type, Eterm spec) {
     ErlHeapFragment *bp;
     ErlOffHeap *off_heap;
-#ifndef ERTS_SMP
-    Process *monitor_p;
-#endif
     Eterm *hp, msg;
 
-#ifndef ERTS_SMP
-    ASSERT(is_internal_pid(system_monitor));
-    monitor_p = erts_proc_lookup(system_monitor);
-    if (!monitor_p || p == monitor_p)
-	return;
-#endif
 
     hp = ERTS_ALLOC_SYSMSG_HEAP(5, &bp, &off_heap, monitor_p);
 
     msg = TUPLE4(hp, am_monitor, p->common.id, type, spec); 
     hp += 5;
 
-#ifdef ERTS_SMP
     enqueue_sys_msg(SYS_MSG_TYPE_SYSMON, p->common.id, NIL, msg, bp);
-#else
-    {
-	ErtsMessage *mp = erts_alloc_message(0, NULL);
-	mp->data.heap_frag = bp;
-	erts_queue_message(monitor_p, 0, mp, msg, am_system);
-    }
-#endif
 
 }
 
@@ -1785,21 +1610,14 @@ profile_scheduler(Eterm scheduler_id, Eterm state) {
     Eterm *hp, msg;
     ErlHeapFragment *bp = NULL;
 
-#ifndef ERTS_SMP
-#define LOCAL_HEAP_SIZE (7 + ERTS_TRACE_PATCH_TS_MAX_SIZE)
-    DeclareTmpHeapNoproc(local_heap,LOCAL_HEAP_SIZE);
-    UseTmpHeapNoproc(LOCAL_HEAP_SIZE);
-    hp = local_heap;
-#else
     Uint hsz;
 
     hsz = 7 + patch_ts_size(erts_system_profile_ts_type)-1;
 	
     bp = new_message_buffer(hsz);
     hp = bp->mem;
-#endif
 
-    erts_smp_mtx_lock(&smq_mtx);
+    erts_mtx_lock(&smq_mtx);
 
     switch (state) {
     case am_active:
@@ -1821,14 +1639,8 @@ profile_scheduler(Eterm scheduler_id, Eterm state) {
     /* Write timestamp in element 6 of the 'msg' tuple */
     hp[-1] = write_ts(erts_system_profile_ts_type, hp, bp, NULL);
 
-#ifndef ERTS_SMP
-    profile_send(NIL, msg);
-    UnUseTmpHeapNoproc(LOCAL_HEAP_SIZE);
-#undef LOCAL_HEAP_SIZE
-#else
     enqueue_sys_msg_unlocked(SYS_MSG_TYPE_SYSPROF, NIL, NIL, msg, bp);
-#endif
-    erts_smp_mtx_unlock(&smq_mtx);
+    erts_mtx_unlock(&smq_mtx);
 
 }
 
@@ -1837,7 +1649,7 @@ profile_scheduler(Eterm scheduler_id, Eterm state) {
 void
 trace_port_open(Port *p, Eterm calling_pid, Eterm drv_name) {
     ErtsTracerNif *tnif = NULL;
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     if (is_tracer_enabled(NULL, 0, &p->common, &tnif, TRACE_FUN_E_PORTS, am_open))
         send_to_tracer_nif(NULL, &p->common, p->common.id, tnif, TRACE_FUN_T_PORTS,
                 am_open, calling_pid, drv_name, am_true);
@@ -1854,9 +1666,9 @@ void
 trace_port(Port *t_p, Eterm what, Eterm data) {
 
     ErtsTracerNif *tnif = NULL;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(t_p)
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(t_p)
 		       || erts_thr_progress_is_blocking());
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     if (is_tracer_enabled(NULL, 0, &t_p->common, &tnif, TRACE_FUN_E_PORTS, what))
         send_to_tracer_nif(NULL, &t_p->common, t_p->common.id, tnif, TRACE_FUN_T_PORTS,
                            what, data, THE_NON_VALUE, am_true);
@@ -1899,9 +1711,9 @@ void
 trace_port_receive(Port *t_p, Eterm caller, Eterm what, ...)
 {
     ErtsTracerNif *tnif = NULL;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(t_p)
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(t_p)
 		       || erts_thr_progress_is_blocking());
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     if (is_tracer_enabled(NULL, 0, &t_p->common, &tnif, TRACE_FUN_E_RECEIVE, am_receive)) {
         /* We can use a stack heap here, as the nif is called in the
            context of a port */
@@ -2016,9 +1828,9 @@ trace_port_send(Port *t_p, Eterm receiver, Eterm msg, int exists)
 {
     ErtsTracerNif *tnif = NULL;
     Eterm op = exists ? am_send : am_send_to_non_existing_process;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(t_p)
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(t_p)
 		       || erts_thr_progress_is_blocking());
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     if (is_tracer_enabled(NULL, 0, &t_p->common, &tnif, TRACE_FUN_E_SEND, op))
         send_to_tracer_nif(NULL, &t_p->common, t_p->common.id, tnif, TRACE_FUN_T_SEND,
                            op, msg, receiver, am_true);
@@ -2027,9 +1839,9 @@ trace_port_send(Port *t_p, Eterm receiver, Eterm msg, int exists)
 void trace_port_send_binary(Port *t_p, Eterm to, Eterm what, char *bin, Sint sz)
 {
     ErtsTracerNif *tnif = NULL;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(t_p)
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(t_p)
 		       || erts_thr_progress_is_blocking());
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     if (is_tracer_enabled(NULL, 0, &t_p->common, &tnif, TRACE_FUN_E_SEND, am_send)) {
         Eterm msg;
         Binary* bptr = NULL;
@@ -2075,9 +1887,9 @@ trace_sched_ports(Port *p, Eterm what) {
 void
 trace_sched_ports_where(Port *t_p, Eterm what, Eterm where) {
     ErtsTracerNif *tnif = NULL;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(t_p)
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(t_p)
 		       || erts_thr_progress_is_blocking());
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     if (is_tracer_enabled(NULL, 0, &t_p->common, &tnif, TRACE_FUN_E_SCHED_PORT, what))
         send_to_tracer_nif(NULL, &t_p->common, t_p->common.id,
                            tnif, TRACE_FUN_T_SCHED_PORT,
@@ -2092,24 +1904,14 @@ profile_runnable_port(Port *p, Eterm status) {
     ErlHeapFragment *bp = NULL;
     Eterm count = make_small(0);
 
-#ifndef ERTS_SMP
-#define LOCAL_HEAP_SIZE (6 + ERTS_TRACE_PATCH_TS_MAX_SIZE)
-
-    DeclareTmpHeapNoproc(local_heap,LOCAL_HEAP_SIZE);
-    UseTmpHeapNoproc(LOCAL_HEAP_SIZE);
-
-    hp = local_heap;
-    
-#else
     Uint hsz;
 
     hsz = 6 + patch_ts_size(erts_system_profile_ts_type)-1;
 
     bp = new_message_buffer(hsz);
     hp = bp->mem;
-#endif
 
-    erts_smp_mtx_lock(&smq_mtx);
+    erts_mtx_lock(&smq_mtx);
 
     msg = TUPLE5(hp, am_profile, p->common.id, status, count,
 		 NIL /* Will be overwritten by timestamp */);
@@ -2118,14 +1920,8 @@ profile_runnable_port(Port *p, Eterm status) {
     /* Write timestamp in element 5 of the 'msg' tuple */
     hp[-1] = write_ts(erts_system_profile_ts_type, hp, bp, NULL);
 
-#ifndef ERTS_SMP
-    profile_send(p->common.id, msg);
-    UnUseTmpHeapNoproc(LOCAL_HEAP_SIZE);
-#undef LOCAL_HEAP_SIZE
-#else
     enqueue_sys_msg_unlocked(SYS_MSG_TYPE_SYSPROF, p->common.id, NIL, msg, bp);
-#endif
-    erts_smp_mtx_unlock(&smq_mtx);
+    erts_mtx_unlock(&smq_mtx);
 }
 
 /* Process profiling */
@@ -2136,23 +1932,13 @@ profile_runnable_proc(Process *p, Eterm status){
     ErlHeapFragment *bp = NULL;
     ErtsCodeMFA *cmfa = NULL;
 
-#ifndef ERTS_SMP
-#define LOCAL_HEAP_SIZE (4 + 6 + ERTS_TRACE_PATCH_TS_MAX_SIZE)
-    DeclareTmpHeapNoproc(local_heap,LOCAL_HEAP_SIZE);
-    UseTmpHeapNoproc(LOCAL_HEAP_SIZE);
-
-    hp = local_heap;
-#else
     ErtsThrPrgrDelayHandle dhndl;
     Uint hsz = 4 + 6 + patch_ts_size(erts_system_profile_ts_type)-1;
-#endif
     /* Assumptions:
      * We possibly don't have the MAIN_LOCK for the process p here.
      * We assume that we can read from p->current and p->i atomically
      */
-#ifdef ERTS_SMP
     dhndl = erts_thr_progress_unmanaged_delay(); /* suspend purge operations */
-#endif
 
     if (!ERTS_PROC_IS_EXITING(p)) {
         if (p->current) {
@@ -2162,14 +1948,12 @@ profile_runnable_proc(Process *p, Eterm status){
         }
     }
 
-#ifdef ERTS_SMP
     if (!cmfa) {
 	hsz -= 4;
     }
 
     bp = new_message_buffer(hsz);
     hp = bp->mem;
-#endif
 
     if (cmfa) {
 	where = TUPLE3(hp, cmfa->module, cmfa->function,
@@ -2179,11 +1963,9 @@ profile_runnable_proc(Process *p, Eterm status){
 	where = make_small(0);
     }
 
-#ifdef ERTS_SMP
     erts_thr_progress_unmanaged_continue(dhndl);
-#endif
 	
-    erts_smp_mtx_lock(&smq_mtx);
+    erts_mtx_lock(&smq_mtx);
 
     msg = TUPLE5(hp, am_profile, p->common.id, status, where,
 		 NIL /* Will be overwritten by timestamp */);
@@ -2192,20 +1974,13 @@ profile_runnable_proc(Process *p, Eterm status){
     /* Write timestamp in element 5 of the 'msg' tuple */
     hp[-1] = write_ts(erts_system_profile_ts_type, hp, bp, NULL);
 
-#ifndef ERTS_SMP
-    profile_send(p->common.id, msg);
-    UnUseTmpHeapNoproc(LOCAL_HEAP_SIZE);
-#undef LOCAL_HEAP_SIZE
-#else
     enqueue_sys_msg_unlocked(SYS_MSG_TYPE_SYSPROF, p->common.id, NIL, msg, bp);
-#endif
-    erts_smp_mtx_unlock(&smq_mtx);
+    erts_mtx_unlock(&smq_mtx);
 }
 /* End system_profile tracing */
 
 
 
-#ifdef ERTS_SMP
 
 typedef struct ErtsSysMsgQ_ ErtsSysMsgQ;
 struct  ErtsSysMsgQ_ {
@@ -2251,7 +2026,7 @@ enqueue_sys_msg_unlocked(enum ErtsSysMsgType type,
 	sys_message_queue = smqp;
     }
     sys_message_queue_end = smqp;
-    erts_smp_cnd_signal(&smq_cnd);
+    erts_cnd_signal(&smq_cnd);
 }
 
 static void
@@ -2261,9 +2036,9 @@ enqueue_sys_msg(enum ErtsSysMsgType type,
 		Eterm msg,
 		ErlHeapFragment *bp)
 {
-    erts_smp_mtx_lock(&smq_mtx);
+    erts_mtx_lock(&smq_mtx);
     enqueue_sys_msg_unlocked(type, from, to, msg, bp);
-    erts_smp_mtx_unlock(&smq_mtx);
+    erts_mtx_unlock(&smq_mtx);
 }
 
 void
@@ -2315,10 +2090,10 @@ sys_msg_disp_failure(ErtsSysMsgQ *smqp, Eterm receiver)
 	    && !erts_system_monitor_flags.busy_port
 	    && !erts_system_monitor_flags.busy_dist_port)
 	    break; /* Everything is disabled */
-	erts_smp_thr_progress_block();
+	erts_thr_progress_block();
 	if (system_monitor == receiver || receiver == NIL)
 	    erts_system_monitor_clear(NULL);
-	erts_smp_thr_progress_unblock();
+	erts_thr_progress_unblock();
 	break;
 	 case SYS_MSG_TYPE_SYSPROF:
 	if (receiver == NIL
@@ -2328,11 +2103,11 @@ sys_msg_disp_failure(ErtsSysMsgQ *smqp, Eterm receiver)
 	    && !erts_system_profile_flags.scheduler)
 		 break;
 	/* Block system to clear flags */
-	erts_smp_thr_progress_block();
+	erts_thr_progress_block();
 	if (system_profile == receiver || receiver == NIL) { 
 		erts_system_profile_clear(NULL);
 	}
-	erts_smp_thr_progress_unblock();
+	erts_thr_progress_unblock();
 	break;
     case SYS_MSG_TYPE_ERRLGR: {
 	char *no_elgger = "(no error logger present)";
@@ -2377,38 +2152,38 @@ static void
 sys_msg_dispatcher_wakeup(void *vwait_p)
 {
     int *wait_p = (int *) vwait_p;
-    erts_smp_mtx_lock(&smq_mtx);
+    erts_mtx_lock(&smq_mtx);
     *wait_p = 0;
-    erts_smp_cnd_signal(&smq_cnd);
-    erts_smp_mtx_unlock(&smq_mtx);
+    erts_cnd_signal(&smq_cnd);
+    erts_mtx_unlock(&smq_mtx);
 }
 
 static void
 sys_msg_dispatcher_prep_wait(void *vwait_p)
 {
     int *wait_p = (int *) vwait_p;
-    erts_smp_mtx_lock(&smq_mtx);
+    erts_mtx_lock(&smq_mtx);
     *wait_p = 1;
-    erts_smp_mtx_unlock(&smq_mtx);
+    erts_mtx_unlock(&smq_mtx);
 }
 
 static void
 sys_msg_dispatcher_fin_wait(void *vwait_p)
 {
     int *wait_p = (int *) vwait_p;
-    erts_smp_mtx_lock(&smq_mtx);
+    erts_mtx_lock(&smq_mtx);
     *wait_p = 0;
-    erts_smp_mtx_unlock(&smq_mtx);
+    erts_mtx_unlock(&smq_mtx);
 }
 
 static void
 sys_msg_dispatcher_wait(void *vwait_p)
 {
     int *wait_p = (int *) vwait_p;
-    erts_smp_mtx_lock(&smq_mtx);
+    erts_mtx_lock(&smq_mtx);
     while (*wait_p)
-	erts_smp_cnd_wait(&smq_cnd, &smq_mtx);
-    erts_smp_mtx_unlock(&smq_mtx);
+	erts_cnd_wait(&smq_cnd, &smq_mtx);
+    erts_mtx_unlock(&smq_mtx);
 }
 
 static void *
@@ -2434,9 +2209,9 @@ sys_msg_dispatcher_func(void *unused)
 	int end_wait = 0;
 	ErtsSysMsgQ *smqp;
 
-	ERTS_SMP_LC_ASSERT(!erts_thr_progress_is_blocking());
+	ERTS_LC_ASSERT(!erts_thr_progress_is_blocking());
 
-	erts_smp_mtx_lock(&smq_mtx);
+	erts_mtx_lock(&smq_mtx);
 
 	/* Free previously used queue ... */
 	while (local_sys_message_queue) {
@@ -2447,21 +2222,21 @@ sys_msg_dispatcher_func(void *unused)
 
 	/* Fetch current trace message queue ... */
 	if (!sys_message_queue) {
-	    erts_smp_mtx_unlock(&smq_mtx);
+	    erts_mtx_unlock(&smq_mtx);
 	    end_wait = 1;
 	    erts_thr_progress_active(NULL, 0);
 	    erts_thr_progress_prepare_wait(NULL);
-	    erts_smp_mtx_lock(&smq_mtx);
+	    erts_mtx_lock(&smq_mtx);
 	}
 
 	while (!sys_message_queue)
-	    erts_smp_cnd_wait(&smq_cnd, &smq_mtx);
+	    erts_cnd_wait(&smq_cnd, &smq_mtx);
 
 	local_sys_message_queue = sys_message_queue;
 	sys_message_queue = NULL;
 	sys_message_queue_end = NULL;
 
-	erts_smp_mtx_unlock(&smq_mtx);
+	erts_mtx_unlock(&smq_mtx);
 
 	if (end_wait) {
 	    erts_thr_progress_finalize_wait(NULL);
@@ -2535,7 +2310,7 @@ sys_msg_dispatcher_func(void *unused)
 #ifdef DEBUG_PRINTOUTS
 		    erts_fprintf(stderr, "delivered\n");
 #endif
-		    erts_smp_proc_unlock(proc, proc_locks);
+		    erts_proc_unlock(proc, proc_locks);
 		}
 	    }
 	    else if (receiver == am_error_logger) {
@@ -2573,7 +2348,7 @@ sys_msg_dispatcher_func(void *unused)
 		sys_msg_disp_failure(smqp, receiver);
 	    drop_sys_msg:
 		if (proc)
-		    erts_smp_proc_unlock(proc, proc_locks);
+		    erts_proc_unlock(proc, proc_locks);
 		if (smqp->bp)
 		    free_message_buffer(smqp->bp);
 #ifdef DEBUG_PRINTOUTS
@@ -2593,7 +2368,7 @@ erts_foreach_sys_msg_in_q(void (*func)(Eterm,
 				       ErlHeapFragment *))
 {
     ErtsSysMsgQ *sm;
-    erts_smp_mtx_lock(&smq_mtx);
+    erts_mtx_lock(&smq_mtx);
     for (sm = sys_message_queue; sm; sm = sm->next) {
 	Eterm to;
 	switch (sm->type) {
@@ -2612,29 +2387,28 @@ erts_foreach_sys_msg_in_q(void (*func)(Eterm,
 	}
 	(*func)(sm->from, to, sm->msg, sm->bp);
     }
-    erts_smp_mtx_unlock(&smq_mtx);
+    erts_mtx_unlock(&smq_mtx);
 }
 
 
 static void
 init_sys_msg_dispatcher(void)
 {
-    erts_smp_thr_opts_t thr_opts = ERTS_SMP_THR_OPTS_DEFAULT_INITER;
+    erts_thr_opts_t thr_opts = ERTS_THR_OPTS_DEFAULT_INITER;
     thr_opts.detached = 1;
     thr_opts.name = "sys_msg_dispatcher";
     init_smq_element_alloc();
     sys_message_queue = NULL;
     sys_message_queue_end = NULL;
-    erts_smp_cnd_init(&smq_cnd);
-    erts_smp_mtx_init(&smq_mtx, "sys_msg_q", NIL,
+    erts_cnd_init(&smq_cnd);
+    erts_mtx_init(&smq_mtx, "sys_msg_q", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_DEBUG);
-    erts_smp_thr_create(&sys_msg_dispatcher_tid,
+    erts_thr_create(&sys_msg_dispatcher_tid,
 			sys_msg_dispatcher_func,
 			NULL,
 			&thr_opts);
 }
 
-#endif
 
 #include "erl_nif.h"
 
@@ -2730,7 +2504,7 @@ static void init_tracer_template(ErtsTracerNif *tnif) {
 }
 
 static Hash *tracer_hash = NULL;
-static erts_smp_rwmtx_t tracer_mtx;
+static erts_rwmtx_t tracer_mtx;
 
 static ErtsTracerNif *
 load_tracer_nif(const ErtsTracer tracer)
@@ -2770,9 +2544,9 @@ load_tracer_nif(const ErtsTracer tracer)
         return NULL;
     }
 
-    erts_smp_rwmtx_rwlock(&tracer_mtx);
+    erts_rwmtx_rwlock(&tracer_mtx);
     tnif = hash_put(tracer_hash, &tnif_tmpl);
-    erts_smp_rwmtx_rwunlock(&tracer_mtx);
+    erts_rwmtx_rwunlock(&tracer_mtx);
 
     return tnif;
 }
@@ -2783,14 +2557,14 @@ lookup_tracer_nif(const ErtsTracer tracer)
     ErtsTracerNif tnif_tmpl;
     ErtsTracerNif *tnif;
     tnif_tmpl.module = ERTS_TRACER_MODULE(tracer);
-    erts_smp_rwmtx_rlock(&tracer_mtx);
+    erts_rwmtx_rlock(&tracer_mtx);
     if ((tnif = hash_get(tracer_hash, &tnif_tmpl)) == NULL) {
-        erts_smp_rwmtx_runlock(&tracer_mtx);
+        erts_rwmtx_runlock(&tracer_mtx);
         tnif = load_tracer_nif(tracer);
         ASSERT(!tnif || tnif->nif_mod);
         return tnif;
     }
-    erts_smp_rwmtx_runlock(&tracer_mtx);
+    erts_rwmtx_runlock(&tracer_mtx);
     ASSERT(tnif->nif_mod);
     return tnif;
 }
@@ -2928,17 +2702,17 @@ send_to_tracer_nif(Process *c_p, ErtsPTabElementCommon *t_p,
                    Eterm t_p_id, ErtsTracerNif *tnif, enum ErtsTracerOpt topt,
                    Eterm tag, Eterm msg, Eterm extra, Eterm pam_result)
 {
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     if (c_p) {
         /* We have to hold the main lock of the currently executing process */
         erts_proc_lc_chk_have_proc_locks(c_p, ERTS_PROC_LOCK_MAIN);
     }
     if (is_internal_pid(t_p->id)) {
         /* We have to have at least one lock */
-        ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks((Process*)t_p) & ERTS_PROC_LOCKS_ALL);
+        ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks((Process*)t_p) & ERTS_PROC_LOCKS_ALL);
     } else {
         ASSERT(is_internal_port(t_p->id));
-        ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked((Port*)t_p));
+        ERTS_LC_ASSERT(erts_lc_is_port_locked((Port*)t_p));
     }
 #endif
 
@@ -2981,17 +2755,17 @@ is_tracer_enabled(Process* c_p, ErtsProcLocks c_p_locks,
                   enum ErtsTracerOpt topt, Eterm tag) {
     Eterm nif_result;
 
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     if (c_p)
-        ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == c_p_locks
+        ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) == c_p_locks
                            || erts_thr_progress_is_blocking());
     if (is_internal_pid(t_p->id)) {
         /* We have to have at least one lock */
-        ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks((Process*)t_p) & ERTS_PROC_LOCKS_ALL
+        ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks((Process*)t_p) & ERTS_PROC_LOCKS_ALL
                            || erts_thr_progress_is_blocking());
     } else {
         ASSERT(is_internal_port(t_p->id));
-        ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked((Port*)t_p)
+        ERTS_LC_ASSERT(erts_lc_is_port_locked((Port*)t_p)
                            || erts_thr_progress_is_blocking());
     }
 #endif
@@ -3013,12 +2787,12 @@ is_tracer_enabled(Process* c_p, ErtsProcLocks c_p_locks,
     if (is_internal_port(t_p->id) || (c_p && c_p->common.id == t_p->id)) {
         ErtsProcLocks c_p_xlocks = 0;
         if (is_internal_pid(t_p->id)) {
-            ERTS_SMP_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) & ERTS_PROC_LOCK_MAIN);
+            ERTS_LC_ASSERT(erts_proc_lc_my_proc_locks(c_p) & ERTS_PROC_LOCK_MAIN);
             if (c_p_locks != ERTS_PROC_LOCKS_ALL) {
                 c_p_xlocks = ~c_p_locks & ERTS_PROC_LOCKS_ALL;
-                if (erts_smp_proc_trylock(c_p, c_p_xlocks) == EBUSY) {
-                    erts_smp_proc_unlock(c_p, c_p_locks & ~ERTS_PROC_LOCK_MAIN);
-                    erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
+                if (erts_proc_trylock(c_p, c_p_xlocks) == EBUSY) {
+                    erts_proc_unlock(c_p, c_p_locks & ~ERTS_PROC_LOCK_MAIN);
+                    erts_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
                 }
             }
         }
@@ -3026,7 +2800,7 @@ is_tracer_enabled(Process* c_p, ErtsProcLocks c_p_locks,
         t_p->trace_flags &= ~TRACEE_FLAGS;
 
         if (c_p_xlocks)
-            erts_smp_proc_unlock(c_p, c_p_xlocks);
+            erts_proc_unlock(c_p, c_p_xlocks);
     }
 
     return 0;
@@ -3066,7 +2840,7 @@ int erts_is_tracer_proc_enabled_send(Process* c_p, ErtsProcLocks c_p_locks,
 
 void erts_tracer_replace(ErtsPTabElementCommon *t_p, const ErtsTracer tracer)
 {
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     if (is_internal_pid(t_p->id) && !erts_thr_progress_is_blocking()) {
         erts_proc_lc_chk_have_proc_locks((Process*)t_p, ERTS_PROC_LOCKS_ALL);
     } else if (is_internal_port(t_p->id)) {
@@ -3184,11 +2958,11 @@ erts_tracer_update(ErtsTracer *tracer, const ErtsTracer new_tracer)
 
 static void init_tracer_nif()
 {
-    erts_smp_rwmtx_opt_t rwmtx_opt = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
-    rwmtx_opt.type = ERTS_SMP_RWMTX_TYPE_EXTREMELY_FREQUENT_READ;
-    rwmtx_opt.lived = ERTS_SMP_RWMTX_LONG_LIVED;
+    erts_rwmtx_opt_t rwmtx_opt = ERTS_RWMTX_OPT_DEFAULT_INITER;
+    rwmtx_opt.type = ERTS_RWMTX_TYPE_EXTREMELY_FREQUENT_READ;
+    rwmtx_opt.lived = ERTS_RWMTX_LONG_LIVED;
 
-    erts_smp_rwmtx_init_opt(&tracer_mtx, &rwmtx_opt, "tracer_mtx", NIL,
+    erts_rwmtx_init_opt(&tracer_mtx, &rwmtx_opt, "tracer_mtx", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_DEBUG);
 
     erts_tracer_nif_clear();
@@ -3198,7 +2972,7 @@ static void init_tracer_nif()
 int erts_tracer_nif_clear()
 {
 
-    erts_smp_rwmtx_rlock(&tracer_mtx);
+    erts_rwmtx_rlock(&tracer_mtx);
     if (!tracer_hash || tracer_hash->nobjs) {
 
         HashFunctions hf;
@@ -3210,19 +2984,19 @@ int erts_tracer_nif_clear()
         hf.meta_free = (HMFREE_FUN) erts_free;
         hf.meta_print = (HMPRINT_FUN) erts_print;
 
-        erts_smp_rwmtx_runlock(&tracer_mtx);
-        erts_smp_rwmtx_rwlock(&tracer_mtx);
+        erts_rwmtx_runlock(&tracer_mtx);
+        erts_rwmtx_rwlock(&tracer_mtx);
 
         if (tracer_hash)
             hash_delete(tracer_hash);
 
         tracer_hash = hash_new(ERTS_ALC_T_TRACER_NIF, "tracer_hash", 10, hf);
 
-        erts_smp_rwmtx_rwunlock(&tracer_mtx);
+        erts_rwmtx_rwunlock(&tracer_mtx);
         return 1;
     }
 
-    erts_smp_rwmtx_runlock(&tracer_mtx);
+    erts_rwmtx_runlock(&tracer_mtx);
     return 0;
 }
 
diff --git a/erts/emulator/beam/erl_trace.h b/erts/emulator/beam/erl_trace.h
index 01fe1e5e23..dbf7ebd2a1 100644
--- a/erts/emulator/beam/erl_trace.h
+++ b/erts/emulator/beam/erl_trace.h
@@ -87,7 +87,6 @@ void erts_set_system_monitor(Eterm monitor);
 Eterm erts_get_system_monitor(void);
 int erts_is_tracer_valid(Process* p);
 
-#ifdef ERTS_SMP
 void erts_check_my_tracer_proc(Process *);
 void erts_block_sys_msg_dispatcher(void);
 void erts_release_sys_msg_dispatcher(void);
@@ -97,7 +96,6 @@ void erts_foreach_sys_msg_in_q(void (*func)(Eterm,
 					    ErlHeapFragment *));
 void erts_queue_error_logger_message(Eterm, Eterm, ErlHeapFragment *);
 void erts_send_sys_msg_proc(Eterm, Eterm, Eterm, ErlHeapFragment *);
-#endif
 
 void trace_send(Process*, Eterm, Eterm);
 void trace_receive(Process*, Eterm, Eterm, ErtsTracingEvent*);
@@ -149,16 +147,12 @@ erts_bif_trace_epilogue(Process *p, Eterm result, int applying,
 			Uint32 flags_meta, BeamInstr* I,
 			ErtsTracer meta_tracer);
 
-#ifdef ERTS_SMP
 void erts_send_pending_trace_msgs(ErtsSchedulerData *esdp);
-#define ERTS_SMP_CHK_PEND_TRACE_MSGS(ESDP)				\
+#define ERTS_CHK_PEND_TRACE_MSGS(ESDP)				\
 do {									\
     if ((ESDP)->pending_trace_msgs)					\
 	erts_send_pending_trace_msgs((ESDP));				\
 } while (0)
-#else
-#define ERTS_SMP_CHK_PEND_TRACE_MSGS(ESDP)
-#endif
 
 #define seq_trace_output(token, msg, type, receiver, process) \
 seq_trace_output_generic((token), (msg), (type), (receiver), (process), NIL)
diff --git a/erts/emulator/beam/erl_unicode.c b/erts/emulator/beam/erl_unicode.c
index 2d1d1443a7..b7a5c45fea 100644
--- a/erts/emulator/beam/erl_unicode.c
+++ b/erts/emulator/beam/erl_unicode.c
@@ -1988,7 +1988,7 @@ char *erts_convert_filename_to_encoding(Eterm name, char *statbuf, size_t statbu
 	is_list(name) || 
 	(allow_empty && is_nil(name))) {
 	Sint need;
-	if ((need = erts_native_filename_need(name,encoding)) < 0) {
+	if ((need = erts_native_filename_need(name, encoding)) < 0) {
 	    return NULL;
 	}
 	if (encoding == ERL_FILENAME_WIN_WCHAR) {
@@ -2152,12 +2152,13 @@ Eterm erts_convert_native_to_filename(Process *p, byte *bytes)
 }
 
 
-Sint erts_native_filename_need(Eterm ioterm, int encoding) 
+Sint erts_native_filename_need(Eterm ioterm, int encoding)
 {
     Eterm *objp;
     Eterm obj;
     DECLARE_ESTACK(stack);
     Sint need = 0;
+    int seen_null = 0;
 
     if (is_atom(ioterm)) {
 	Atom* ap;
@@ -2194,6 +2195,22 @@ Sint erts_native_filename_need(Eterm ioterm, int encoding)
 	default:
 	    need = -1;
 	}
+        /*
+         * Do not allow null in
+         * the middle of filenames
+         */
+        if (need > 0) {
+            byte *name = ap->name;
+            int len = ap->len;
+            for (i = 0; i < len; i++) {
+                if (name[i] == 0)
+                    seen_null = 1;
+                else if (seen_null) {
+                    need = -1;
+                    break;
+                }
+            }
+        }
 	DESTROY_ESTACK(stack);
 	return need;
     }
@@ -2224,6 +2241,16 @@ L_Again:   /* Restart with sublist, old listend was pushed on stack */
 		if (is_small(obj)) { /* Always small */
 		    for(;;) {
 			Uint x = unsigned_val(obj);
+                        /*
+                         * Do not allow null in
+                         * the middle of filenames
+                         */
+                        if (x == 0)
+                            seen_null = 1;
+                        else if (seen_null) {
+                            DESTROY_ESTACK(stack);
+                            return ((Sint) -1);
+                        }
 			switch (encoding) {
 			case ERL_FILENAME_LATIN1:
 			    if (x > 255) {
@@ -2497,6 +2524,38 @@ void erts_copy_utf8_to_utf16_little(byte *target, byte *bytes, int num_chars)
 }
 
 /*
+ * *** Requirements on Raw Filename Format ***
+ *
+ * These requirements are due to the 'filename' module
+ * in stdlib. This since it is documented that it
+ * should be able to operate on raw filenames as well
+ * as ordinary filenames.
+ *
+ * A raw filename *must* be a byte sequence where:
+ * 1. Codepoints 0-127 (7-bit ascii) *must* be encoded
+ *    as a byte with the corresponding value. That is,
+ *    the most significant bit in the byte encoding the
+ *    codepoint is never set.
+ * 2. Codepoints greater than 127 *must* be encoded
+ *    with the most significant bit set in *every* byte
+ *    encoding it.
+ *
+ * Latin1 and UTF-8 meet these requirements while
+ * UTF-16 and UTF-32 don't.
+ *
+ * On Windows filenames are natively stored as malformed
+ * UTF-16LE (lonely surrogates may appear). A more correct
+ * description than UTF-16 would be an array of 16-bit
+ * words... In order to meet the requirements of the
+ * raw file format we convert the malformed UTF-16LE to
+ * malformed UTF-8 which meet the requirements.
+ *
+ * Note that these requirements are today only OTP
+ * internal (erts-stdlib internal) requirements that
+ * could be changed.
+ */
+
+/*
  * This internal bif converts a filename to whatever format is suitable for the file driver
  * It also adds zero termination so that prim_file needn't bother with the character encoding
  * of the file driver 
@@ -2507,6 +2566,12 @@ BIF_RETTYPE prim_file_internal_name2native_1(BIF_ALIST_1)
     Sint need;
     Eterm bin_term;
     byte* bin_p;
+
+    /*
+     * See comment on "Requirements on Raw Filename Format"
+     * above.
+     */
+
     /* Prim file explicitly does not allow atoms, although we could 
        very well cope with it. Instead of letting 'file' handle them,
        it would probably be more efficient to handle them here. Subject to 
@@ -2515,6 +2580,7 @@ BIF_RETTYPE prim_file_internal_name2native_1(BIF_ALIST_1)
 	BIF_ERROR(BIF_P,BADARG);
     }
     if (is_binary(BIF_ARG_1)) {
+        int seen_null = 0;
 	byte *temp_alloc = NULL;
 	byte *bytes;
 	byte *err_pos;
@@ -2524,10 +2590,18 @@ BIF_RETTYPE prim_file_internal_name2native_1(BIF_ALIST_1)
 	size = binary_size(BIF_ARG_1);
 	bytes = erts_get_aligned_binary_bytes(BIF_ARG_1, &temp_alloc);
 	if (encoding != ERL_FILENAME_WIN_WCHAR) {
+            Uint i;
 	    /*Add 0 termination only*/
 	    bin_term = new_binary(BIF_P, NULL, size+1);
 	    bin_p = binary_bytes(bin_term);
-	    memcpy(bin_p,bytes,size);
+            for (i = 0; i < size; i++) {
+                /* Don't allow null in the middle of filenames... */
+                if (bytes[i] == 0)
+                    seen_null = 1;
+                else if (seen_null)
+                    goto bin_name_error;
+                bin_p[i] = bytes[i];
+            }
 	    bin_p[size]=0;
 	    erts_free_aligned_binary_bytes(temp_alloc);
 	    BIF_RET(bin_term);
@@ -2541,6 +2615,11 @@ BIF_RETTYPE prim_file_internal_name2native_1(BIF_ALIST_1)
 	    bin_term = new_binary(BIF_P, 0, (size+1)*2);
 	    bin_p = binary_bytes(bin_term);
 	    while (size--) {
+                /* Don't allow null in the middle of filenames... */
+                if (*bytes == 0)
+                    seen_null = 1;
+                else if (seen_null)
+                    goto bin_name_error;
 		*bin_p++ = *bytes++;
 		*bin_p++ = 0;
 	    }
@@ -2558,11 +2637,14 @@ BIF_RETTYPE prim_file_internal_name2native_1(BIF_ALIST_1)
 	bin_p[num_chars*2+1] = 0;
 	erts_free_aligned_binary_bytes(temp_alloc);
 	BIF_RET(bin_term);
+    bin_name_error:
+        erts_free_aligned_binary_bytes(temp_alloc);
+        BIF_ERROR(BIF_P,BADARG);
     } /* binary */   
 	    
 
-    if ((need = erts_native_filename_need(BIF_ARG_1,encoding)) < 0) {
-	BIF_ERROR(BIF_P,BADARG);
+    if ((need = erts_native_filename_need(BIF_ARG_1, encoding)) < 0) {
+        BIF_ERROR(BIF_P,BADARG);
     }
     if (encoding == ERL_FILENAME_WIN_WCHAR) {
 	need += 2;
@@ -2596,6 +2678,11 @@ BIF_RETTYPE prim_file_internal_native2name_1(BIF_ALIST_1)
     Eterm ret;
     int mac = 0;
 
+    /*
+     * See comment on "Requirements on Raw Filename Format"
+     * above.
+     */
+
     if (is_not_binary(BIF_ARG_1)) {
 	BIF_ERROR(BIF_P,BADARG);
     }
diff --git a/erts/emulator/beam/erl_utils.h b/erts/emulator/beam/erl_utils.h
index 3d28b05752..44d8c85867 100644
--- a/erts/emulator/beam/erl_utils.h
+++ b/erts/emulator/beam/erl_utils.h
@@ -22,15 +22,11 @@
 #define ERL_UTILS_H__
 
 #include "sys.h"
-#include "erl_smp.h"
 #include "erl_printf.h"
 
 struct process;
 
 typedef struct {
-#ifdef DEBUG
-    int smp_api;
-#endif
     union {
 	Uint64 not_atomic;
 	erts_atomic64_t atomic;
@@ -38,70 +34,25 @@ typedef struct {
 } erts_interval_t;
 
 void erts_interval_init(erts_interval_t *);
-void erts_smp_interval_init(erts_interval_t *);
 Uint64 erts_step_interval_nob(erts_interval_t *);
 Uint64 erts_step_interval_relb(erts_interval_t *);
-Uint64 erts_smp_step_interval_nob(erts_interval_t *);
-Uint64 erts_smp_step_interval_relb(erts_interval_t *);
 Uint64 erts_ensure_later_interval_nob(erts_interval_t *, Uint64);
 Uint64 erts_ensure_later_interval_acqb(erts_interval_t *, Uint64);
-Uint64 erts_smp_ensure_later_interval_nob(erts_interval_t *, Uint64);
-Uint64 erts_smp_ensure_later_interval_acqb(erts_interval_t *, Uint64);
-ERTS_GLB_INLINE Uint64 erts_current_interval_nob__(erts_interval_t *);
-ERTS_GLB_INLINE Uint64 erts_current_interval_acqb__(erts_interval_t *);
 ERTS_GLB_INLINE Uint64 erts_current_interval_nob(erts_interval_t *);
 ERTS_GLB_INLINE Uint64 erts_current_interval_acqb(erts_interval_t *);
-ERTS_GLB_INLINE Uint64 erts_smp_current_interval_nob(erts_interval_t *);
-ERTS_GLB_INLINE Uint64 erts_smp_current_interval_acqb(erts_interval_t *);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
 ERTS_GLB_INLINE Uint64
-erts_current_interval_nob__(erts_interval_t *icp)
-{
-    return (Uint64) erts_atomic64_read_nob(&icp->counter.atomic);
-}
-
-ERTS_GLB_INLINE Uint64
-erts_current_interval_acqb__(erts_interval_t *icp)
-{
-    return (Uint64) erts_atomic64_read_acqb(&icp->counter.atomic);
-}
-
-ERTS_GLB_INLINE Uint64
 erts_current_interval_nob(erts_interval_t *icp)
 {
-    ASSERT(!icp->smp_api);
-    return erts_current_interval_nob__(icp);
+    return (Uint64) erts_atomic64_read_nob(&icp->counter.atomic);
 }
 
 ERTS_GLB_INLINE Uint64
 erts_current_interval_acqb(erts_interval_t *icp)
 {
-    ASSERT(!icp->smp_api);
-    return erts_current_interval_acqb__(icp);
-}
-
-ERTS_GLB_INLINE Uint64
-erts_smp_current_interval_nob(erts_interval_t *icp)
-{
-    ASSERT(icp->smp_api);
-#ifdef ERTS_SMP
-    return erts_current_interval_nob__(icp);
-#else
-    return icp->counter.not_atomic;
-#endif
-}
-
-ERTS_GLB_INLINE Uint64
-erts_smp_current_interval_acqb(erts_interval_t *icp)
-{
-    ASSERT(icp->smp_api);
-#ifdef ERTS_SMP
-    return erts_current_interval_acqb__(icp);
-#else
-    return icp->counter.not_atomic;
-#endif
+    return (Uint64) erts_atomic64_read_acqb(&icp->counter.atomic);
 }
 
 #endif /* ERTS_GLB_INLINE_INCL_FUNC_DEF */
diff --git a/erts/emulator/beam/erl_vm.h b/erts/emulator/beam/erl_vm.h
index 0b8d78c469..76980b5871 100644
--- a/erts/emulator/beam/erl_vm.h
+++ b/erts/emulator/beam/erl_vm.h
@@ -46,8 +46,6 @@
  */
 #define ERTS_X_REGS_ALLOCATED (MAX_REG+3)
 
-#define INPUT_REDUCTIONS (2 * CONTEXT_REDS)
-
 #define H_DEFAULT_SIZE  233        /* default (heap + stack) min size */
 #define VH_DEFAULT_SIZE  32768     /* default virtual (bin) heap min size (words) */
 #define H_DEFAULT_MAX_SIZE 0       /* default max heap size is off */
@@ -55,7 +53,7 @@
 #define CP_SIZE 1
 
 #define ErtsHAllocLockCheck(P) \
-  ERTS_SMP_LC_ASSERT(erts_dbg_check_halloc_lock((P)))
+  ERTS_LC_ASSERT(erts_dbg_check_halloc_lock((P)))
 
 
 #ifdef DEBUG
@@ -102,9 +100,11 @@
   if ((ptr) == (endp)) {					\
      ;								\
   } else if (HEAP_START(p) <= (ptr) && (ptr) < HEAP_TOP(p)) {	\
+     ASSERT(HEAP_TOP(p) == (endp));                             \
      HEAP_TOP(p) = (ptr);					\
   } else {							\
-     erts_heap_frag_shrink(p, ptr);					\
+     ASSERT(MBUF(p)->mem + MBUF(p)->used_size == (endp));       \
+     erts_heap_frag_shrink(p, ptr);                             \
   }
 
 #define HeapWordsLeft(p) (HEAP_LIMIT(p) - HEAP_TOP(p))
@@ -157,6 +157,7 @@ typedef struct op_entry {
    Uint32 mask[3];		/* Signature mask. */
    unsigned involves_r;		/* Needs special attention when matching. */
    int sz;			/* Number of loaded words. */
+   int adjust;                  /* Adjustment for start of instruction. */
    char* pack;			/* Instructions for packing engine. */
    char* sign;			/* Signature string. */
 } OpEntry;
@@ -199,11 +200,24 @@ extern int erts_pd_initial_size;/* Initial Process dictionary table size */
 
 #include "erl_term.h"
 
-#ifdef NO_JUMP_TABLE 
-#define BeamOp(Op) (Op)
+#if defined(NO_JUMP_TABLE)
+#  define BeamOpsAreInitialized() (1)
+#  define BeamOpCodeAddr(OpCode) ((BeamInstr)(OpCode))
 #else
 extern void** beam_ops;
-#define BeamOp(Op) beam_ops[(Op)]
+#  define BeamOpsAreInitialized() (beam_ops != 0)
+#  define BeamOpCodeAddr(OpCode) ((BeamInstr)beam_ops[(OpCode)])
 #endif
 
+#if defined(ARCH_64) && defined(CODE_MODEL_SMALL)
+#  define BeamCodeAddr(InstrWord) ((BeamInstr)(Uint32)(InstrWord))
+#  define BeamSetCodeAddr(InstrWord, Addr) (((InstrWord) & ~((1ull << 32)-1)) | (Addr))
+#  define BeamExtraData(InstrWord) ((InstrWord) >> 32)
+#else
+#  define BeamCodeAddr(InstrWord) ((BeamInstr)(InstrWord))
+#  define BeamSetCodeAddr(InstrWord, Addr) (Addr)
+#endif
+
+#define BeamIsOpCode(InstrWord, OpCode) (BeamCodeAddr(InstrWord) == BeamOpCodeAddr(OpCode))
+
 #endif	/* __ERL_VM_H__ */
diff --git a/erts/emulator/beam/erlang_dtrace.d b/erts/emulator/beam/erlang_dtrace.d
index 237889e0f5..d0b10e0306 100644
--- a/erts/emulator/beam/erlang_dtrace.d
+++ b/erts/emulator/beam/erlang_dtrace.d
@@ -634,72 +634,6 @@ provider erlang {
      */
     probe aio_pool__get(char *, int);
 
-    /* Probes for efile_drv.c */
-
-    /**
-     * Entry into the efile_drv.c file I/O driver
-     *
-     * For a list of command numbers used by this driver, see the section
-     * "Guide to efile_drv.c probe arguments" in ../../../HOWTO/DTRACE.md.
-     * That section also contains explanation of the various integer and
-     * string arguments that may be present when any particular probe fires.
-     *
-     * NOTE: Not all Linux platforms (using SystemTap) can support
-     *       arguments beyond arg9.
-     *
-     *
-     * TODO: Adding the port string, args[10], is a pain.  Making that
-     *       port string available to all the other efile_drv.c probes
-     *       will be more pain.  Is the pain worth it?  If yes, then
-     *       add them everywhere else and grit our teeth.  If no, then
-     *       rip it out.
-     *
-     * @param thread-id number of the scheduler Pthread                   arg0
-     * @param tag number: {thread-id, tag} uniquely names a driver operation
-     * @param user-tag string                                             arg2
-     * @param command number                                              arg3
-     * @param string argument 1                                           arg4
-     * @param string argument 2                                           arg5
-     * @param integer argument 1                                          arg6
-     * @param integer argument 2                                          arg7
-     * @param integer argument 3                                          arg8
-     * @param integer argument 4                                          arg9
-     * @param port the port ID of the busy port                       args[10]
-     */
-    probe efile_drv__entry(int, int, char *, int, char *, char *,
-                           int64_t, int64_t, int64_t, int64_t, char *);
-
-    /**
-     * Entry into the driver's internal work function.  Computation here
-     * is performed by a async worker pool Pthread.
-     *
-     * @param thread-id number
-     * @param tag number
-     * @param command number
-     */
-    probe efile_drv__int_entry(int, int, int);
-
-    /**
-     * Return from the driver's internal work function.
-     *
-     * @param thread-id number
-     * @param tag number
-     * @param command number
-     */
-    probe efile_drv__int_return(int, int, int);
-
-    /**
-     * Return from the efile_drv.c file I/O driver
-     *
-     * @param thread-id number                                            arg0
-     * @param tag number                                                  arg1
-     * @param user-tag string                                             arg2
-     * @param command number                                              arg3
-     * @param Success? 1 is success, 0 is failure                         arg4
-     * @param If failure, the errno of the error.                         arg5
-     */
-    probe efile_drv__return(int, int, char *, int, int, int);
-
 
 /*
  * The set of probes called by the erlang tracer nif backend. In order
diff --git a/erts/emulator/beam/erlang_lttng.h b/erts/emulator/beam/erlang_lttng.h
index 4e869671f7..feb05f4f4c 100644
--- a/erts/emulator/beam/erlang_lttng.h
+++ b/erts/emulator/beam/erlang_lttng.h
@@ -159,21 +159,6 @@ TRACEPOINT_EVENT(
 
 TRACEPOINT_EVENT(
     org_erlang_otp,
-    driver_event,
-    TP_ARGS(
-        char*, pid,
-        char*, port,
-        char*, driver
-    ),
-    TP_FIELDS(
-        ctf_string(pid, pid)
-        ctf_string(port, port)
-        ctf_string(driver, driver)
-    )
-)
-
-TRACEPOINT_EVENT(
-    org_erlang_otp,
     driver_timeout,
     TP_ARGS(
         char*, pid,
diff --git a/erts/emulator/beam/export.c b/erts/emulator/beam/export.c
index 828c833ffc..946ffeffb8 100644
--- a/erts/emulator/beam/export.c
+++ b/erts/emulator/beam/export.c
@@ -41,16 +41,13 @@
 
 static IndexTable export_tables[ERTS_NUM_CODE_IX];  /* Active not locked */
 
-static erts_smp_atomic_t total_entries_bytes;
-
-#include "erl_smp.h"
+static erts_atomic_t total_entries_bytes;
 
 /* This lock protects the staging export table from concurrent access
  * AND it protects the staging table from becoming active.
  */
-erts_smp_mtx_t export_staging_lock;
+erts_mtx_t export_staging_lock;
 
-extern BeamInstr* em_call_error_handler;
 extern BeamInstr* em_call_traced_function;
 
 struct export_entry
@@ -85,17 +82,13 @@ static struct export_blob* entry_to_blob(struct export_entry* ee)
 void
 export_info(fmtfn_t to, void *to_arg)
 {
-#ifdef ERTS_SMP
     int lock = !ERTS_IS_CRASH_DUMPING;
     if (lock)
 	export_staging_lock();
-#endif
     index_info(to, to_arg, &export_tables[erts_active_code_ix()]);
     hash_info(to, to_arg, &export_tables[erts_staging_code_ix()].htable);
-#ifdef ERTS_SMP
     if (lock)
 	export_staging_unlock();
-#endif
 }
 
 
@@ -129,14 +122,17 @@ export_alloc(struct export_entry* tmpl_e)
 	Export* obj;
 
 	blob = (struct export_blob*) erts_alloc(ERTS_ALC_T_EXPORT, sizeof(*blob));
-	erts_smp_atomic_add_nob(&total_entries_bytes, sizeof(*blob));
+	erts_atomic_add_nob(&total_entries_bytes, sizeof(*blob));
 	obj = &blob->exp;
 	obj->info.op =  0;
 	obj->info.u.gen_bp = NULL;
 	obj->info.mfa.module = tmpl->info.mfa.module;
 	obj->info.mfa.function = tmpl->info.mfa.function;
 	obj->info.mfa.arity = tmpl->info.mfa.arity;
-	obj->beam[0] = (BeamInstr) em_call_error_handler;
+        obj->beam[0] = 0;
+        if (BeamOpsAreInitialized()) {
+            obj->beam[0] = BeamOpCodeAddr(op_call_error_handler);
+        }
 	obj->beam[1] = 0;
 
 	for (ix=0; ix<ERTS_NUM_CODE_IX; ix++) {
@@ -173,7 +169,7 @@ export_free(struct export_entry* obj)
     }
     DBG_TRACE_MFA_P(&blob->exp.info.mfa, "export blob deallocation at %p", &blob->exp);
     erts_free(ERTS_ALC_T_EXPORT, blob);
-    erts_smp_atomic_add_nob(&total_entries_bytes, -sizeof(*blob));
+    erts_atomic_add_nob(&total_entries_bytes, -sizeof(*blob));
 }
 
 void
@@ -182,9 +178,9 @@ init_export_table(void)
     HashFunctions f;
     int i;
 
-    erts_smp_mtx_init(&export_staging_lock, "export_tab", NIL,
+    erts_mtx_init(&export_staging_lock, "export_tab", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
-    erts_smp_atomic_init_nob(&total_entries_bytes, 0);
+    erts_atomic_init_nob(&total_entries_bytes, 0);
 
     f.hash = (H_FUN) export_hash;
     f.cmp  = (HCMP_FUN) export_cmp;
@@ -273,7 +269,7 @@ erts_find_function(Eterm m, Eterm f, unsigned int a, ErtsCodeIndex code_ix)
     ee = hash_get(&export_tables[code_ix].htable, init_template(&templ, m, f, a));
     if (ee == NULL ||
 	(ee->ep->addressv[code_ix] == ee->ep->beam &&
-	 ee->ep->beam[0] != (BeamInstr) BeamOp(op_i_generic_breakpoint))) {
+	 ! BeamIsOpCode(ee->ep->beam[0], op_i_generic_breakpoint))) {
 	return NULL;
     }
     return ee->ep;
@@ -373,7 +369,7 @@ int export_table_sz(void)
 }
 int export_entries_sz(void)
 {
-    return erts_smp_atomic_read_nob(&total_entries_bytes);
+    return erts_atomic_read_nob(&total_entries_bytes);
 }
 Export *export_get(Export *e)
 {
diff --git a/erts/emulator/beam/export.h b/erts/emulator/beam/export.h
index 7c812b306c..194e514b12 100644
--- a/erts/emulator/beam/export.h
+++ b/erts/emulator/beam/export.h
@@ -66,14 +66,14 @@ Export *export_get(Export*);
 void export_start_staging(void);
 void export_end_staging(int commit);
 
-extern erts_smp_mtx_t export_staging_lock;
-#define export_staging_lock()	erts_smp_mtx_lock(&export_staging_lock)
-#define export_staging_unlock()	erts_smp_mtx_unlock(&export_staging_lock)
+extern erts_mtx_t export_staging_lock;
+#define export_staging_lock()	erts_mtx_lock(&export_staging_lock)
+#define export_staging_unlock()	erts_mtx_unlock(&export_staging_lock)
 
 #include "beam_load.h" /* For em_* extern declarations */ 
 #define ExportIsBuiltIn(EntryPtr) 			\
 (((EntryPtr)->addressv[erts_active_code_ix()] == (EntryPtr)->beam) && \
- ((EntryPtr)->beam[0] == (BeamInstr) em_apply_bif))
+ (BeamIsOpCode((EntryPtr)->beam[0], op_apply_bif)))
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
diff --git a/erts/emulator/beam/external.c b/erts/emulator/beam/external.c
index c0a3838d42..9cc5e71afa 100644
--- a/erts/emulator/beam/external.c
+++ b/erts/emulator/beam/external.c
@@ -122,8 +122,9 @@ static int encode_size_struct_int(struct TTBSizeContext_*, ErtsAtomCacheMap *acm
 
 static Export binary_to_term_trap_export;
 static BIF_RETTYPE binary_to_term_trap_1(BIF_ALIST_1);
-static BIF_RETTYPE binary_to_term_int(Process* p, Uint32 flags, Eterm bin, Binary* context_b,
-				      Export *bif, Eterm arg0, Eterm arg1);
+static Sint transcode_dist_obuf(ErtsDistOutputBuf*, DistEntry*, Uint32 dflags, Sint reds);
+
+
 
 void erts_init_external(void) {
     erts_init_trap_export(&term_to_binary_trap_export,
@@ -222,23 +223,10 @@ erts_destroy_atom_cache_map(ErtsAtomCacheMap *acmp)
 static ERTS_INLINE void
 insert_acache_map(ErtsAtomCacheMap *acmp, Eterm atom, Uint32 dflags)
 {
-    /*
-     * If the receiver do not understand utf8 atoms
-     * and this atom cannot be represented in latin1,
-     * we are not allowed to cache it.
-     *
-     * In this case all atoms are assumed to have
-     * latin1 encoding in the cache. By refusing it
-     * in the cache we will instead encode it using
-     * ATOM_UTF8_EXT/SMALL_ATOM_UTF8_EXT which the
-     * receiver do not recognize and tear down the
-     * connection.
-     */
-    if (acmp && acmp->sz < ERTS_MAX_INTERNAL_ATOM_CACHE_ENTRIES
-	&& ((dflags & DFLAG_UTF8_ATOMS)
-	    || atom_tab(atom_val(atom))->latin1_chars >= 0)) {
+    if (acmp && acmp->sz < ERTS_MAX_INTERNAL_ATOM_CACHE_ENTRIES) {
 	int ix;
 	ASSERT(acmp->hdr_sz < 0);
+        ASSERT(dflags & DFLAG_UTF8_ATOMS);
 	ix = atom2cix(atom);
 	if (acmp->cache[ix].iix < 0) {
 	    acmp->cache[ix].iix = acmp->sz;
@@ -258,9 +246,7 @@ get_iix_acache_map(ErtsAtomCacheMap *acmp, Eterm atom, Uint32 dflags)
 	ASSERT(is_atom(atom));
 	ix = atom2cix(atom);
 	if (acmp->cache[ix].iix < 0) {
-	    ASSERT(acmp->sz == ERTS_MAX_INTERNAL_ATOM_CACHE_ENTRIES
-		   || (!(dflags & DFLAG_UTF8_ATOMS)
-		       && atom_tab(atom_val(atom))->latin1_chars < 0));
+	    ASSERT(acmp->sz == ERTS_MAX_INTERNAL_ATOM_CACHE_ENTRIES);
 	    return -1;
 	}
 	else {
@@ -274,7 +260,6 @@ void
 erts_finalize_atom_cache_map(ErtsAtomCacheMap *acmp, Uint32 dflags)
 {
     if (acmp) {
-	int utf8_atoms = (int) (dflags & DFLAG_UTF8_ATOMS);
 	int long_atoms = 0; /* !0 if one or more atoms are longer than 255. */
 	int i;
 	int sz;
@@ -285,6 +270,7 @@ erts_finalize_atom_cache_map(ErtsAtomCacheMap *acmp, Uint32 dflags)
 	    + 1 /* number of internal cache entries */
 	    ;
 	int min_sz;
+        ASSERT(dflags & DFLAG_UTF8_ATOMS);
 	ASSERT(acmp->hdr_sz < 0);
 	/* Make sure cache update instructions fit */
 	min_sz = fix_sz+(2+4)*acmp->sz;
@@ -296,7 +282,7 @@ erts_finalize_atom_cache_map(ErtsAtomCacheMap *acmp, Uint32 dflags)
 	    atom = acmp->cache[acmp->cix[i]].atom;
 	    ASSERT(is_atom(atom));
 	    a = atom_tab(atom_val(atom));
-	    len = (int) (utf8_atoms ? a->len : a->latin1_chars);
+	    len = (int) a->len;
 	    ASSERT(len >= 0);
 	    if (!long_atoms && len > 255)
 		long_atoms = 1;
@@ -366,18 +352,77 @@ byte *erts_encode_ext_dist_header_setup(byte *ctl_ext, ErtsAtomCacheMap *acmp)
     }
 }
 
-byte *erts_encode_ext_dist_header_finalize(byte *ext, ErtsAtomCache *cache, Uint32 dflags)
+
+#define PASS_THROUGH 'p'
+
+Sint erts_encode_ext_dist_header_finalize(ErtsDistOutputBuf* ob,
+                                          DistEntry* dep,
+                                          Uint32 dflags,
+                                          Sint reds)
 {
     byte *ip;
     byte instr_buf[(2+4)*ERTS_ATOM_CACHE_SIZE];
     int ci, sz;
     byte dist_hdr_flags;
     int long_atoms;
-    int utf8_atoms = (int) (dflags & DFLAG_UTF8_ATOMS);
-    register byte *ep = ext;
-    ASSERT(ep[0] == VERSION_MAGIC);
-    if (ep[1] != DIST_HEADER)
-	return ext;
+    register byte *ep = ob->extp;
+    ASSERT(dflags & DFLAG_UTF8_ATOMS);
+
+    /*
+     * The buffer can have different layouts at this point depending on
+     * what was known when encoded:
+     *
+     * Pending connection: CtrlTerm [, MsgTerm]
+     * With atom cache   : VERSION_MAGIC, DIST_HEADER, ..., CtrlTerm [, MsgTerm]
+     * No atom cache     : VERSION_MAGIC, CtrlTerm [, VERSION_MAGIC, MsgTerm]
+     */
+
+    if (ep[0] != VERSION_MAGIC || dep->transcode_ctx) {
+        /*
+         * Was encoded without atom cache toward pending connection.
+         */
+        ASSERT(ep[0] == SMALL_TUPLE_EXT || ep[0] == LARGE_TUPLE_EXT);
+
+        if (~dflags & (DFLAG_DIST_MONITOR | DFLAG_DIST_MONITOR_NAME)
+            && ep[0] == SMALL_TUPLE_EXT
+            && ep[1] == 4
+            && ep[2] == SMALL_INTEGER_EXT
+            && (ep[3] == DOP_MONITOR_P ||
+                ep[3] == DOP_MONITOR_P_EXIT ||
+                ep[3] == DOP_DEMONITOR_P)) {
+            /*
+             * Receiver does not support process monitoring.
+             * Suppress monitor control msg (see erts_dsig_send_monitor)
+             * by converting it to an empty (tick) packet.
+             */
+            ob->ext_endp = ob->extp;
+            return reds;
+        }
+        if (~dflags & (DFLAG_BIT_BINARIES | DFLAG_EXPORT_PTR_TAG
+                       | DFLAG_DIST_HDR_ATOM_CACHE)) {
+            reds = transcode_dist_obuf(ob, dep, dflags, reds);
+            if (reds < 0)
+                return reds;
+            ep = ob->extp;
+        }
+        if (dflags & DFLAG_DIST_HDR_ATOM_CACHE) {
+            /*
+             * Encoding was done without atom caching but receiver expects
+             * a dist header, so we prepend an empty one.
+             */
+            *--ep = 0; /* NumberOfAtomCacheRefs */
+            *--ep = DIST_HEADER;
+            *--ep = VERSION_MAGIC;
+        }
+        goto done;
+    }
+    else if (ep[1] != DIST_HEADER) {
+        ASSERT(ep[1] == SMALL_TUPLE_EXT || ep[1] == LARGE_TUPLE_EXT);
+        ASSERT(!(dflags & DFLAG_DIST_HDR_ATOM_CACHE));
+        /* Node without atom cache, 'pass through' needed */
+        *--ep = PASS_THROUGH;
+        goto done;
+    }
 
     dist_hdr_flags = ep[2];
     long_atoms = ERTS_DIST_HDR_LONG_ATOMS_FLG & ((int) dist_hdr_flags);
@@ -405,6 +450,7 @@ byte *erts_encode_ext_dist_header_finalize(byte *ext, ErtsAtomCache *cache, Uint
 			 / sizeof(Uint32))+1];
 	register Uint32 flgs;
 	int iix, flgs_bytes, flgs_buf_ix, used_half_bytes;
+        ErtsAtomCache* cache = dep->cache;
 #ifdef DEBUG
 	int tot_used_half_bytes;
 #endif
@@ -447,17 +493,9 @@ byte *erts_encode_ext_dist_header_finalize(byte *ext, ErtsAtomCache *cache, Uint
 		Atom *a;
 		cache->out_arr[cix] = atom;
 		a = atom_tab(atom_val(atom));
-		if (utf8_atoms) {
-		    sz = a->len;
-		    ep -= sz;
-		    sys_memcpy((void *) ep, (void *) a->name, sz);
-		}
-		else {
-		    ASSERT(0 <= a->latin1_chars && a->latin1_chars <= MAX_ATOM_CHARACTERS);
-		    ep -= a->latin1_chars;
-		    sz = erts_utf8_to_latin1(ep, a->name, a->len);
-		    ASSERT(a->latin1_chars == sz);
-		}
+                sz = a->len;
+                ep -= sz;
+                sys_memcpy((void *) ep, (void *) a->name, sz);
 		if (long_atoms) {
 		    ep -= 2;
 		    put_int16(sz, ep);
@@ -504,12 +542,16 @@ byte *erts_encode_ext_dist_header_finalize(byte *ext, ErtsAtomCache *cache, Uint
 		break;
 	    }
 	}
+        reds -= 3; /*was ERTS_PORT_REDS_DIST_CMD_FINALIZE*/
     }
     --ep;
     put_int8(ci, ep);
     *--ep = DIST_HEADER;
     *--ep = VERSION_MAGIC;
-    return ep;
+done:
+    ob->extp = ep;
+    ASSERT(&ob->data[0] <= ob->extp && ob->extp < ob->ext_endp);
+    return reds < 0 ? 0 : reds;
 }
 
 int erts_encode_dist_ext_size(Eterm term, Uint32 flags, ErtsAtomCacheMap *acmp,
@@ -520,7 +562,7 @@ int erts_encode_dist_ext_size(Eterm term, Uint32 flags, ErtsAtomCacheMap *acmp,
 	return -1;
     } else {
 #ifndef ERTS_DEBUG_USE_DIST_SEP
-	if (!(flags & DFLAG_DIST_HDR_ATOM_CACHE))
+	if (!(flags & (DFLAG_DIST_HDR_ATOM_CACHE | DFLAG_NO_MAGIC)))
 #endif
 	    sz++ /* VERSION_MAGIC */;
 
@@ -536,7 +578,7 @@ int erts_encode_dist_ext_size_int(Eterm term, struct erts_dsig_send_context* ctx
 	return -1;
     } else {
 #ifndef ERTS_DEBUG_USE_DIST_SEP
-	if (!(ctx->flags & DFLAG_DIST_HDR_ATOM_CACHE))
+	if (!(ctx->flags & (DFLAG_DIST_HDR_ATOM_CACHE | DFLAG_NO_MAGIC)))
 #endif
 	    sz++ /* VERSION_MAGIC */;
 
@@ -568,7 +610,7 @@ int erts_encode_dist_ext(Eterm term, byte **ext, Uint32 flags, ErtsAtomCacheMap
 {
     if (!ctx || !ctx->wstack.wstart) {
     #ifndef ERTS_DEBUG_USE_DIST_SEP
-	if (!(flags & DFLAG_DIST_HDR_ATOM_CACHE))
+	if (!(flags & (DFLAG_DIST_HDR_ATOM_CACHE | DFLAG_NO_MAGIC)))
     #endif
 	    *(*ext)++ = VERSION_MAGIC;
     }
@@ -616,7 +658,7 @@ erts_make_dist_ext_copy(ErtsDistExternal *edep, Uint xsize)
     sys_memcpy((void *) ep, (void *) edep, dist_ext_sz);
     ep += dist_ext_sz;
     if (new_edep->dep)
-	erts_smp_refc_inc(&new_edep->dep->refc, 1);
+        erts_ref_dist_entry(new_edep->dep);
     new_edep->extp = ep;
     new_edep->ext_endp = ep + ext_sz;
     new_edep->heap_size = -1;
@@ -629,7 +671,8 @@ erts_prepare_dist_ext(ErtsDistExternal *edep,
 		      byte *ext,
 		      Uint size,
 		      DistEntry *dep,
-		      ErtsAtomCache *cache)
+		      ErtsAtomCache *cache,
+                      Uint32 *connection_id)
 {
 #undef ERTS_EXT_FAIL
 #undef ERTS_EXT_HDR_FAIL
@@ -642,7 +685,7 @@ erts_prepare_dist_ext(ErtsDistExternal *edep,
 #endif
 
     register byte *ep = ext;
-    int utf8_atoms = (int) (dep->flags & DFLAG_UTF8_ATOMS);
+    ASSERT(dep->flags & DFLAG_UTF8_ATOMS);
 
     edep->heap_size = -1;
     edep->ext_endp = ext+size;
@@ -650,32 +693,34 @@ erts_prepare_dist_ext(ErtsDistExternal *edep,
     if (size < 2)
 	ERTS_EXT_FAIL;
 
+    if (!dep)
+        ERTS_INTERNAL_ERROR("Invalid use");
+
     if (ep[0] != VERSION_MAGIC) {
 	erts_dsprintf_buf_t *dsbufp = erts_create_logger_dsbuf();
-	if (dep)
-	    erts_dsprintf(dsbufp,
-			  "** Got message from incompatible erlang on "
-			  "channel %d\n",
-			  dist_entry_channel_no(dep));
-	else
-	    erts_dsprintf(dsbufp,
-			  "** Attempt to convert old incompatible "
-			  "binary %d\n",
-			  *ep);
+        erts_dsprintf(dsbufp,
+                      "** Got message from incompatible erlang on "
+                      "channel %d\n",
+                      dist_entry_channel_no(dep));
 	erts_send_error_to_logger_nogl(dsbufp);
 	ERTS_EXT_FAIL;
     }
 
     edep->flags = 0;
     edep->dep = dep;
-    if (dep) {
-	erts_smp_de_rlock(dep);
-	if (dep->flags & DFLAG_DIST_HDR_ATOM_CACHE)
-	    edep->flags |= ERTS_DIST_EXT_DFLAG_HDR;
-	    
-	edep->flags |= (dep->connection_id & ERTS_DIST_EXT_CON_ID_MASK);
-	erts_smp_de_runlock(dep);
+
+    erts_de_rlock(dep);
+
+    if (dep->status != ERTS_DE_SFLG_CONNECTED &&
+	dep->status != ERTS_DE_SFLG_PENDING) {
+        erts_de_runlock(dep);
+        return ERTS_PREP_DIST_EXT_CLOSED;
     }
+    if (dep->flags & DFLAG_DIST_HDR_ATOM_CACHE)
+        edep->flags |= ERTS_DIST_EXT_DFLAG_HDR;
+
+    *connection_id = dep->connection_id;
+    edep->connection_id = dep->connection_id;
 
     if (ep[1] != DIST_HEADER) {
 	if (edep->flags & ERTS_DIST_EXT_DFLAG_HDR)
@@ -802,9 +847,7 @@ erts_prepare_dist_ext(ErtsDistExternal *edep,
 		    CHKSIZE(len);
 		    atom = erts_atom_put((byte *) ep,
 					 len,
-					 (utf8_atoms
-					  ? ERTS_ATOM_ENC_UTF8
-					  : ERTS_ATOM_ENC_LATIN1),
+                                         ERTS_ATOM_ENC_UTF8,
 					 0);
 		    if (is_non_value(atom))
 			ERTS_EXT_HDR_FAIL;
@@ -835,14 +878,15 @@ erts_prepare_dist_ext(ErtsDistExternal *edep,
 	ERTS_EXT_FAIL;
 #endif
 
-    return 0;
+    erts_de_runlock(dep);
+
+    return ERTS_PREP_DIST_EXT_SUCCESS;
 
 #undef CHKSIZE
 #undef ERTS_EXT_FAIL
 #undef ERTS_EXT_HDR_FAIL
 
- bad_hdr:
-    if (dep) {
+ bad_hdr: {
 	erts_dsprintf_buf_t *dsbufp = erts_create_logger_dsbuf();
 	erts_dsprintf(dsbufp,
 		      "%T got a corrupted distribution header from %T "
@@ -855,10 +899,11 @@ erts_prepare_dist_ext(ErtsDistExternal *edep,
 	erts_dsprintf(dsbufp, ">>");
 	erts_send_warning_to_logger_nogl(dsbufp);
     }
- fail:
-    if (dep)
-	erts_kill_dist_connection(dep, dep->connection_id);
-    return -1;
+ fail: {
+	erts_de_runlock(dep);
+	erts_kill_dist_connection(dep, *connection_id);
+    }
+    return ERTS_PREP_DIST_EXT_FAILED;
 }
 
 static void
@@ -889,7 +934,7 @@ bad_dist_ext(ErtsDistExternal *edep)
 		erts_dsprintf(dsbufp, ", %d=%T", i, edep->attab.atom[i]);
 	}
 	erts_send_warning_to_logger_nogl(dsbufp);
-	erts_kill_dist_connection(dep, ERTS_DIST_EXT_CON_ID(edep));
+	erts_kill_dist_connection(dep, edep->connection_id);
     }
 }
 
@@ -1214,7 +1259,8 @@ typedef struct B2TContext_t {
     ErtsBinary2TermState b2ts;
     Uint32 flags;
     SWord reds;
-    Eterm trap_bin;
+    Uint used_bytes; /* In: boolean, Out: bytes */
+    Eterm trap_bin;  /* THE_NON_VALUE if not exported */
     Export *bif;
     Eterm arg[2];
     enum B2TState state;
@@ -1308,6 +1354,11 @@ binary2term_prepare(ErtsBinary2TermState *state, byte *data, Sint data_size,
 
 	    ctx->u.uc.dbytes = state->extp;
 	    ctx->u.uc.dleft = dest_len;
+            if (ctx->used_bytes) {
+                ASSERT(ctx->used_bytes == 1);
+                 /* to be subtracted by stream.avail_in when done */
+                ctx->used_bytes = data_size;
+            }
 	    ctx->state = B2TUncompressChunk;
             *ctxp = ctx;
         }
@@ -1410,13 +1461,15 @@ static int b2t_context_destructor(Binary *context_bin)
     return 1;
 }
 
+static BIF_RETTYPE binary_to_term_int(Process*, Eterm bin, B2TContext*);
+
+
 static BIF_RETTYPE binary_to_term_trap_1(BIF_ALIST_1)
 {
     Binary *context_bin = erts_magic_ref2bin(BIF_ARG_1);
     ASSERT(ERTS_MAGIC_BIN_DESTRUCTOR(context_bin) == b2t_context_destructor);
 
-    return binary_to_term_int(BIF_P, 0, THE_NON_VALUE, context_bin, NULL,
-			      THE_NON_VALUE, THE_NON_VALUE);
+    return binary_to_term_int(BIF_P, THE_NON_VALUE, ERTS_MAGIC_BIN_DATA(context_bin));
 }
 
 
@@ -1442,6 +1495,8 @@ static B2TContext* b2t_export_context(Process* p, B2TContext* src)
                                                  b2t_context_destructor);
     B2TContext* ctx = ERTS_MAGIC_BIN_DATA(context_b);
     Eterm* hp;
+
+    ASSERT(is_non_value(src->trap_bin));
     sys_memcpy(ctx, src, sizeof(B2TContext));
     if (ctx->state >= B2TDecode && ctx->u.dc.next == &src->u.dc.res) {
         ctx->u.dc.next = &ctx->u.dc.res;
@@ -1451,8 +1506,7 @@ static B2TContext* b2t_export_context(Process* p, B2TContext* src)
     return ctx;
 }
 
-static BIF_RETTYPE binary_to_term_int(Process* p, Uint32 flags, Eterm bin, Binary* context_b,
-				      Export *bif_init, Eterm arg0, Eterm arg1)
+static BIF_RETTYPE binary_to_term_int(Process* p, Eterm bin, B2TContext *ctx)
 {
     BIF_RETTYPE ret_val;
 #ifdef EXTREME_B2T_TRAPPING
@@ -1460,25 +1514,17 @@ static BIF_RETTYPE binary_to_term_int(Process* p, Uint32 flags, Eterm bin, Binar
 #else
     SWord initial_reds = (Uint)(ERTS_BIF_REDS_LEFT(p) * B2T_BYTES_PER_REDUCTION);
 #endif
-    B2TContext c_buff;
-    B2TContext *ctx;
     int is_first_call;
 
-    if (context_b == NULL) {
+    if (is_value(bin)) {
 	/* Setup enough to get started */
         is_first_call = 1;
-        ctx = &c_buff;
 	ctx->state = B2TPrepare;
         ctx->aligned_alloc = NULL;
-        ctx->flags = flags;
-	ctx->bif = bif_init;
-	ctx->arg[0] = arg0;
-	ctx->arg[1] = arg1;
-        IF_DEBUG(ctx->trap_bin = THE_NON_VALUE;)
     } else {
-        is_first_call = 0;
-	ctx = ERTS_MAGIC_BIN_DATA(context_b);
+        ASSERT(is_value(ctx->trap_bin));
         ASSERT(ctx->state != B2TPrepare);
+        is_first_call = 0;
     }
     ctx->reds = initial_reds;
 
@@ -1522,6 +1568,10 @@ static BIF_RETTYPE binary_to_term_int(Process* p, Uint32 flags, Eterm bin, Binar
                      && zret == Z_STREAM_END
                      && ctx->u.uc.dleft == 0) {
                 ctx->reds -= chunk;
+                if (ctx->used_bytes) {
+                    ASSERT(ctx->used_bytes > 5 + ctx->u.uc.stream.avail_in);
+                    ctx->used_bytes -= ctx->u.uc.stream.avail_in;
+                }
                 ctx->state = B2TSizeInit;
             }
             else {
@@ -1540,11 +1590,11 @@ static BIF_RETTYPE binary_to_term_int(Process* p, Uint32 flags, Eterm bin, Binar
             break;
 
         case B2TDecodeInit:
-            if (ctx == &c_buff && ctx->b2ts.extsize > ctx->reds) {
+            if (is_non_value(ctx->trap_bin) && ctx->b2ts.extsize > ctx->reds) {
                 /* dec_term will maybe trap, allocate space for magic bin
                    before result term to make it easy to trim with HRelease.
                  */
-                ctx = b2t_export_context(p, &c_buff);
+                ctx = b2t_export_context(p, ctx);
             }
             ctx->u.dc.ep = ctx->b2ts.extp;
             ctx->u.dc.res = (Eterm) (UWord) NULL;
@@ -1587,6 +1637,25 @@ static BIF_RETTYPE binary_to_term_int(Process* p, Uint32 flags, Eterm bin, Binar
 	    return ret_val;
 
         case B2TDone:
+            if (ctx->used_bytes) {
+                Eterm *hp;
+                Eterm used;
+                if (!ctx->b2ts.exttmp) {
+                    ASSERT(ctx->used_bytes == 1);
+                    ctx->used_bytes = (ctx->u.dc.ep - ctx->b2ts.extp
+                                       +1); /* VERSION_MAGIC */
+                }
+                if (IS_USMALL(0, ctx->used_bytes)) {
+                    hp = erts_produce_heap(&ctx->u.dc.factory, 3, 0);
+                    used = make_small(ctx->used_bytes);
+                }
+                else {
+                    hp = erts_produce_heap(&ctx->u.dc.factory, 3+BIG_UINT_HEAP_SIZE, 0);
+                    used = uint_to_big(ctx->used_bytes, hp);
+                    hp += BIG_UINT_HEAP_SIZE;
+                }
+                ctx->u.dc.res = TUPLE2(hp, ctx->u.dc.res, used);
+            }
             b2t_destroy_context(ctx);
 
             if (ctx->u.dc.factory.hp > ctx->u.dc.factory.hp_end) {
@@ -1607,11 +1676,10 @@ static BIF_RETTYPE binary_to_term_int(Process* p, Uint32 flags, Eterm bin, Binar
         }
     }while (ctx->reds > 0 || ctx->state >= B2TDone);
 
-    if (ctx == &c_buff) {
-        ASSERT(ctx->trap_bin == THE_NON_VALUE);
-        ctx = b2t_export_context(p, &c_buff);
+    if (is_non_value(ctx->trap_bin)) {
+        ctx = b2t_export_context(p, ctx);
+        ASSERT(is_value(ctx->trap_bin));
     }
-    ASSERT(ctx->trap_bin != THE_NON_VALUE);
 
     if (is_first_call) {
         erts_set_gc_state(p, 0);
@@ -1628,23 +1696,35 @@ HIPE_WRAPPER_BIF_DISABLE_GC(binary_to_term, 1)
 
 BIF_RETTYPE binary_to_term_1(BIF_ALIST_1)
 {
-    return binary_to_term_int(BIF_P, 0, BIF_ARG_1, NULL, bif_export[BIF_binary_to_term_1],
-			      BIF_ARG_1, THE_NON_VALUE);
+    B2TContext ctx;
+
+    ctx.flags = 0;
+    ctx.used_bytes = 0;
+    ctx.trap_bin = THE_NON_VALUE;
+    ctx.bif = bif_export[BIF_binary_to_term_1];
+    ctx.arg[0] = BIF_ARG_1;
+    ctx.arg[1] = THE_NON_VALUE;
+    return binary_to_term_int(BIF_P, BIF_ARG_1, &ctx);
 }
 
 HIPE_WRAPPER_BIF_DISABLE_GC(binary_to_term, 2)
 
 BIF_RETTYPE binary_to_term_2(BIF_ALIST_2)
 {
+    B2TContext ctx;
     Eterm opts;
     Eterm opt;
-    Uint32 flags = 0;
 
+    ctx.flags = 0;
+    ctx.used_bytes = 0;
     opts = BIF_ARG_2;
     while (is_list(opts)) {
         opt = CAR(list_val(opts));
         if (opt == am_safe) {
-            flags |= ERTS_DIST_EXT_BTT_SAFE;
+            ctx.flags |= ERTS_DIST_EXT_BTT_SAFE;
+        }
+        else if (opt == am_used) {
+            ctx.used_bytes = 1;
         }
 	else {
             goto error;
@@ -1655,8 +1735,11 @@ BIF_RETTYPE binary_to_term_2(BIF_ALIST_2)
     if (is_not_nil(opts))
         goto error;
 
-    return binary_to_term_int(BIF_P, flags, BIF_ARG_1, NULL, bif_export[BIF_binary_to_term_2],
-			      BIF_ARG_1, BIF_ARG_2);
+    ctx.trap_bin = THE_NON_VALUE;
+    ctx.bif = bif_export[BIF_binary_to_term_2];
+    ctx.arg[0] = BIF_ARG_1;
+    ctx.arg[1] = BIF_ARG_2;
+    return binary_to_term_int(BIF_P, BIF_ARG_1, &ctx);
 
 error:
     BIF_ERROR(BIF_P, BADARG);
@@ -2093,7 +2176,7 @@ enc_atom(ErtsAtomCacheMap *acmp, Eterm atom, byte *ep, Uint32 dflags)
 {
     int iix;
     int len;
-    int utf8_atoms = (int) (dflags & DFLAG_UTF8_ATOMS);
+    const int utf8_atoms = (int) (dflags & DFLAG_UTF8_ATOMS);
 
     ASSERT(is_atom(atom));
 
@@ -2488,8 +2571,6 @@ enc_term_int(TTBEncodeContext* ctx, ErtsAtomCacheMap *acmp, Eterm obj, byte* ep,
 	    break;
 	}
 
-    L_jump_start:
-
 	if (ctx && --r <= 0) {
 	    *reds = 0;
 	    ctx->obj = obj;
@@ -2497,6 +2578,8 @@ enc_term_int(TTBEncodeContext* ctx, ErtsAtomCacheMap *acmp, Eterm obj, byte* ep,
 	    WSTACK_SAVE(s, &ctx->wstack);
 	    return -1;
 	}
+
+    L_jump_start:
 	switch(tag_val_def(obj)) {
 	case NIL_DEF:
 	    *ep++ = NIL_EXT;
@@ -2861,62 +2944,27 @@ enc_term_int(TTBEncodeContext* ctx, ErtsAtomCacheMap *acmp, Eterm obj, byte* ep,
 		ErlFunThing* funp = (ErlFunThing *) fun_val(obj);
 		int ei;
 
-		if ((dflags & DFLAG_NEW_FUN_TAGS) != 0) {
-		    *ep++ = NEW_FUN_EXT;
-		    WSTACK_PUSH2(s, ENC_PATCH_FUN_SIZE,
-				 (UWord) ep); /* Position for patching in size */
-		    ep += 4;
-		    *ep = funp->arity;
-		    ep += 1;
-		    sys_memcpy(ep, funp->fe->uniq, 16);
-		    ep += 16;
-		    put_int32(funp->fe->index, ep);
-		    ep += 4;
-		    put_int32(funp->num_free, ep);
-		    ep += 4;
-		    ep = enc_atom(acmp, funp->fe->module, ep, dflags);
-		    ep = enc_term(acmp, make_small(funp->fe->old_index), ep, dflags, off_heap);
-		    ep = enc_term(acmp, make_small(funp->fe->old_uniq), ep, dflags, off_heap);
-		    ep = enc_pid(acmp, funp->creator, ep, dflags);
-		} else {
-		    /*
-		     * Communicating with an obsolete erl_interface or
-		     * jinterface node. Convert the fun to a tuple to
-		     * avoid crasching.
-		     */
-		
-		    /* Tag, arity */
-		    *ep++ = SMALL_TUPLE_EXT;
-		    put_int8(5, ep);
-		    ep += 1;
-		
-		    /* 'fun' */
-		    ep = enc_atom(acmp, am_fun, ep, dflags);
-		
-		    /* Module name */
-		    ep = enc_atom(acmp, funp->fe->module, ep, dflags);
-		
-		    /* Index, Uniq */
-		    *ep++ = INTEGER_EXT;
-		    put_int32(funp->fe->old_index, ep);
-		    ep += 4;
-		    *ep++ = INTEGER_EXT;
-		    put_int32(funp->fe->old_uniq, ep);
-		    ep += 4;
-		
-		    /* Environment sub-tuple arity */
-		    ASSERT(funp->num_free < MAX_ARG);
-		    *ep++ = SMALL_TUPLE_EXT;
-		    put_int8(funp->num_free, ep);
-		    ep += 1;
-		}
-		for (ei = funp->num_free-1; ei > 0; ei--) {
+		ASSERT(dflags & DFLAG_NEW_FUN_TAGS);
+                *ep++ = NEW_FUN_EXT;
+                WSTACK_PUSH2(s, ENC_PATCH_FUN_SIZE,
+                             (UWord) ep); /* Position for patching in size */
+                ep += 4;
+                *ep = funp->arity;
+                ep += 1;
+                sys_memcpy(ep, funp->fe->uniq, 16);
+                ep += 16;
+                put_int32(funp->fe->index, ep);
+                ep += 4;
+                put_int32(funp->num_free, ep);
+                ep += 4;
+                ep = enc_atom(acmp, funp->fe->module, ep, dflags);
+                ep = enc_term(acmp, make_small(funp->fe->old_index), ep, dflags, off_heap);
+                ep = enc_term(acmp, make_small(funp->fe->old_uniq), ep, dflags, off_heap);
+                ep = enc_pid(acmp, funp->creator, ep, dflags);
+
+		for (ei = funp->num_free-1; ei >= 0; ei--) {
 		    WSTACK_PUSH2(s, ENC_TERM, (UWord) funp->env[ei]);
 		}
-		if (funp->num_free != 0) {
-		    obj = funp->env[0];
-		    goto L_jump_start;
-		}
 	    }
 	    break;
 	}
@@ -3109,7 +3157,7 @@ dec_term(ErtsDistExternal *edep,
 #if defined(ARCH_64)
 		*objp = make_small(sn);
 #else
-		if (MY_IS_SSMALL(sn)) {
+		if (IS_SSMALL(sn)) {
 		    *objp = make_small(sn);
 		} else {
 		    *objp = small_to_big(sn, hp);
@@ -3254,6 +3302,7 @@ dec_term_atom_common:
             n--;
 	    if (ctx) {
                 if (reds < n) {
+                    ASSERT(reds > 0);
 		    ctx->state = B2TDecodeList;
 		    ctx->u.dc.remaining_n = n - reds;
 		    n = reds;
@@ -3994,6 +4043,7 @@ dec_term_atom_common:
     if (ctx) {
         ctx->state = B2TDone;
 	ctx->reds = reds;
+        ctx->u.dc.ep = ep;
     }
 
     return ep;
@@ -4263,24 +4313,12 @@ encode_size_struct_int(TTBSizeContext* ctx, ErtsAtomCacheMap *acmp, Eterm obj,
 	    {
 		ErlFunThing* funp = (ErlFunThing *) fun_val(obj);
 		
-		if ((dflags & DFLAG_NEW_FUN_TAGS) != 0) {
-		    result += 20+1+1+4;	/* New ID + Tag */
-		    result += 4; /* Length field (number of free variables */
-		    result += encode_size_struct2(acmp, funp->creator, dflags);
-		    result += encode_size_struct2(acmp, funp->fe->module, dflags);
-		    result += 2 * (1+4);	/* Index, Uniq */
-		} else {
-		    /*
-		     * Size when fun is mapped to a tuple.
-		     */
-		    result += 1 + 1; /* Tuple tag, arity */
-		    result += 1 + 1 + 2 +
-			atom_tab(atom_val(am_fun))->len; /* 'fun' */
-		    result += 1 + 1 + 2 +
-			atom_tab(atom_val(funp->fe->module))->len; /* Module name */
-		    result += 2 * (1 + 4); /* Index + Uniq */
-		    result += 1 + (funp->num_free < 0x100 ? 1 : 4);
-		}
+                ASSERT(dflags & DFLAG_NEW_FUN_TAGS);
+                result += 20+1+1+4;	/* New ID + Tag */
+                result += 4; /* Length field (number of free variables */
+                result += encode_size_struct2(acmp, funp->creator, dflags);
+                result += encode_size_struct2(acmp, funp->fe->module, dflags);
+                result += 2 * (1+4);	/* Index, Uniq */
 		if (funp->num_free > 1) {
 		    WSTACK_PUSH2(s, (UWord) (funp->env + 1),
 				    (UWord) TERM_ARRAY_OP(funp->num_free-1));
@@ -4368,7 +4406,7 @@ decoded_size(byte *ep, byte* endp, int internal_tags, B2TContext* ctx)
         }
     }
     else
-        reds = 0; /* not used but compiler warns anyway */
+        ERTS_UNDEF(reds, 0);
 
     heap_size = 0;
     terms = 1;
@@ -4678,3 +4716,177 @@ error:
 #undef SKIP2
 #undef CHKSIZE
 }
+
+
+struct transcode_context {
+    enum {
+        TRANSCODE_DEC_MSG_SIZE,
+        TRANSCODE_DEC_MSG,
+        TRANSCODE_ENC_CTL,
+        TRANSCODE_ENC_MSG
+    }state;
+    Eterm ctl_term;
+    Eterm* ctl_heap;
+    ErtsHeapFactory ctl_factory;
+    Eterm* msg_heap;
+    B2TContext b2t;
+    TTBEncodeContext ttb;
+#ifdef DEBUG
+    ErtsDistOutputBuf* dbg_ob;
+#endif
+};
+
+void transcode_free_ctx(DistEntry* dep)
+{
+    struct transcode_context* ctx = dep->transcode_ctx;
+
+    erts_factory_close(&ctx->ctl_factory);
+    erts_free(ERTS_ALC_T_DIST_TRANSCODE, ctx->ctl_heap);
+
+    if (ctx->msg_heap) {
+        erts_factory_close(&ctx->b2t.u.dc.factory);
+        erts_free(ERTS_ALC_T_DIST_TRANSCODE, ctx->msg_heap);
+    }
+    erts_free(ERTS_ALC_T_DIST_TRANSCODE, ctx);
+    dep->transcode_ctx = NULL;
+}
+
+Sint transcode_dist_obuf(ErtsDistOutputBuf* ob,
+                         DistEntry* dep,
+                         Uint32 dflags,
+                         Sint reds)
+{
+    Sint hsz;
+    byte* decp;
+    const int have_msg = !!ob->msg_start;
+    int i;
+    struct transcode_context* ctx = dep->transcode_ctx;
+
+    if (!ctx) { /* first call for 'ob' */
+
+        if (~dflags & (DFLAG_BIT_BINARIES | DFLAG_EXPORT_PTR_TAG)) {
+            /*
+             * Receiver does not support bitstrings and/or export funs.
+             * We need to transcode control and message terms to use tuple fallbacks.
+             */
+            ctx = erts_alloc(ERTS_ALC_T_DIST_TRANSCODE, sizeof(struct transcode_context));
+            dep->transcode_ctx = ctx;
+        #ifdef DEBUG
+            ctx->dbg_ob = ob;
+        #endif
+
+            hsz = decoded_size(ob->extp, ob->ext_endp, 0, NULL);
+            ctx->ctl_heap = erts_alloc(ERTS_ALC_T_DIST_TRANSCODE, hsz*sizeof(Eterm));
+            erts_factory_tmp_init(&ctx->ctl_factory, ctx->ctl_heap, hsz, ERTS_ALC_T_DIST_TRANSCODE);
+            ctx->msg_heap = NULL;
+
+            decp = dec_term(NULL, &ctx->ctl_factory, ob->extp, &ctx->ctl_term, NULL);
+            if (have_msg) {
+                ASSERT(decp == ob->msg_start); (void)decp;
+                ctx->b2t.u.sc.ep = NULL;
+                ctx->b2t.state = B2TSize;
+                ctx->b2t.aligned_alloc = NULL;
+                ctx->b2t.b2ts.exttmp = 0;
+                ctx->state = TRANSCODE_DEC_MSG_SIZE;
+            }
+            else {
+                ASSERT(decp == ob->ext_endp);
+                ctx->state = TRANSCODE_ENC_CTL;
+            }
+        }
+        else {
+            /*
+             * No need for full transcoding, but primitive receiver (erl_/jinterface)
+             * expects VERSION_MAGIC before both control and message terms.
+             */
+            if (ob->msg_start) {
+                Sint ctl_bytes = ob->msg_start - ob->extp;
+                ASSERT(ob->extp < ob->msg_start && ob->msg_start < ob->ext_endp);
+                /* Move control term back 1 byte to make room */
+                sys_memmove(ob->extp-1, ob->extp, ctl_bytes);
+                *--(ob->msg_start) = VERSION_MAGIC;
+                --(ob->extp);
+                reds -= ctl_bytes / (B2T_BYTES_PER_REDUCTION * B2T_MEMCPY_FACTOR);
+            }
+            *--(ob->extp) = VERSION_MAGIC;
+            goto done;
+        }
+    }
+    else {
+        ASSERT(ctx->dbg_ob == ob);
+    }
+    ctx->b2t.reds = reds * B2T_BYTES_PER_REDUCTION;
+
+    switch (ctx->state) {
+    case TRANSCODE_DEC_MSG_SIZE:
+        hsz = decoded_size(ob->msg_start, ob->ext_endp, 0, &ctx->b2t);
+        if (ctx->b2t.state == B2TSize) {
+            return -1;
+        }
+        ASSERT(ctx->b2t.state == B2TDecodeInit);
+        ctx->msg_heap = erts_alloc(ERTS_ALC_T_DIST_TRANSCODE, hsz*sizeof(Eterm));
+        ctx->b2t.u.dc.ep = ob->msg_start;
+        ctx->b2t.u.dc.res = (Eterm) NULL;
+        ctx->b2t.u.dc.next = &ctx->b2t.u.dc.res;
+        erts_factory_tmp_init(&ctx->b2t.u.dc.factory,
+                              ctx->msg_heap, hsz, ERTS_ALC_T_DIST_TRANSCODE);
+        ctx->b2t.u.dc.flat_maps.wstart = NULL;
+        ctx->b2t.u.dc.hamt_array.pstart = NULL;
+        ctx->b2t.state = B2TDecode;
+
+        ctx->state = TRANSCODE_DEC_MSG;
+    case TRANSCODE_DEC_MSG:
+        if (ctx->b2t.reds <= 0)
+            ctx->b2t.reds = 1;
+        decp = dec_term(NULL, NULL, NULL, NULL, &ctx->b2t);
+        if (ctx->b2t.state < B2TDone) {
+            return -1;
+        }
+        ASSERT(ctx->b2t.state == B2TDone);
+        ASSERT(decp && decp <= ob->ext_endp);
+        reds = ctx->b2t.reds / B2T_BYTES_PER_REDUCTION;
+        b2t_destroy_context(&ctx->b2t);
+
+        ctx->state = TRANSCODE_ENC_CTL;
+    case TRANSCODE_ENC_CTL:
+        if (!(dflags & DFLAG_DIST_HDR_ATOM_CACHE)) {
+            ASSERT(!(dflags & DFLAG_NO_MAGIC));
+            ob->extp -= 2; /* VERSION_MAGIC x 2 */
+        }
+        ob->ext_endp = ob->extp;
+        i = erts_encode_dist_ext(ctx->ctl_term, &ob->ext_endp, dflags,
+                                 NULL, NULL, NULL);
+        ASSERT(i == 0); (void)i;
+        ASSERT(ob->ext_endp <= ob->alloc_endp);
+
+        if (!have_msg) {
+            break;
+        }
+        ob->msg_start = ob->ext_endp;
+        ctx->ttb.wstack.wstart = NULL;
+        ctx->ttb.flags = dflags;
+        ctx->ttb.level = 0;
+
+        ctx->state = TRANSCODE_ENC_MSG;
+    case TRANSCODE_ENC_MSG:
+        reds *= TERM_TO_BINARY_LOOP_FACTOR;
+        if (erts_encode_dist_ext(ctx->b2t.u.dc.res, &ob->ext_endp, dflags, NULL,
+                                 &ctx->ttb, &reds)) {
+            return -1;
+        }
+        reds /= TERM_TO_BINARY_LOOP_FACTOR;
+
+        ASSERT(ob->ext_endp <= ob->alloc_endp);
+
+    }
+    transcode_free_ctx(dep);
+
+done:
+    if (!(dflags & DFLAG_DIST_HDR_ATOM_CACHE))
+        *--(ob->extp) = PASS_THROUGH;
+
+    if (reds < 0)
+        reds = 0;
+
+    return reds;
+}
diff --git a/erts/emulator/beam/external.h b/erts/emulator/beam/external.h
index f00426cc16..f9f8abcc27 100644
--- a/erts/emulator/beam/external.h
+++ b/erts/emulator/beam/external.h
@@ -109,35 +109,26 @@ typedef struct {
 } ErtsAtomTranslationTable;
 
 /*
- * These flags are tagged onto the high bits of a connection ID and stored in
- * the ErtsDistExternal structure's flags field.  They are used to indicate
- * various bits of state necessary to decode binaries in a variety of
- * scenarios. The mask ERTS_DIST_EXT_CON_ID_MASK is used later to separate the
- * connection ID from the flags. Be careful to ensure that the mask does not
- * overlap any of the bits used for flags, or ERTS will leak flags bits into
- * connection IDs and leak connection ID bits into the flags.
+ * These flags are stored in the ErtsDistExternal structure's flags field.
+ * They are used to indicate various bits of state necessary to decode binaries
+ * in a variety of scenarios.
  */
-#define ERTS_DIST_EXT_DFLAG_HDR      ((Uint32) 0x80000000)
-#define ERTS_DIST_EXT_ATOM_TRANS_TAB ((Uint32) 0x40000000)
-#define ERTS_DIST_EXT_BTT_SAFE       ((Uint32) 0x20000000)
-#define ERTS_DIST_EXT_CON_ID_MASK    ((Uint32) 0x1fffffff)
+#define ERTS_DIST_EXT_DFLAG_HDR      ((Uint32) 0x1)
+#define ERTS_DIST_EXT_ATOM_TRANS_TAB ((Uint32) 0x2)
+#define ERTS_DIST_EXT_BTT_SAFE       ((Uint32) 0x4)
+
+#define ERTS_DIST_CON_ID_MASK ((Uint32) 0x00ffffff) /* also in net_kernel.erl */
 
-#define ERTS_DIST_EXT_CON_ID(DIST_EXTP) \
-  ((DIST_EXTP)->flags & ERTS_DIST_EXT_CON_ID_MASK)
 typedef struct {
     DistEntry *dep;
     byte *extp;
     byte *ext_endp;
     Sint heap_size;
+    Uint32 connection_id;
     Uint32 flags;
     ErtsAtomTranslationTable attab;
 } ErtsDistExternal;
 
-typedef struct {
-    int have_header;
-    int cache_entries;
-} ErtsDistHeaderPeek;
-
 #define ERTS_DIST_EXT_SIZE(EDEP) \
   (sizeof(ErtsDistExternal) \
    - (((EDEP)->flags & ERTS_DIST_EXT_ATOM_TRANS_TAB) \
@@ -163,7 +154,7 @@ void erts_finalize_atom_cache_map(ErtsAtomCacheMap *, Uint32);
 
 Uint erts_encode_ext_dist_header_size(ErtsAtomCacheMap *);
 byte *erts_encode_ext_dist_header_setup(byte *, ErtsAtomCacheMap *);
-byte *erts_encode_ext_dist_header_finalize(byte *, ErtsAtomCache *, Uint32);
+Sint erts_encode_ext_dist_header_finalize(ErtsDistOutputBuf*, DistEntry *, Uint32 dflags, Sint reds);
 struct erts_dsig_send_context;
 int erts_encode_dist_ext_size(Eterm, Uint32, ErtsAtomCacheMap*, Uint* szp);
 int erts_encode_dist_ext_size_int(Eterm term, struct erts_dsig_send_context* ctx, Uint* szp);
@@ -177,16 +168,18 @@ Uint erts_encode_ext_size_ets(Eterm);
 void erts_encode_ext(Eterm, byte **);
 byte* erts_encode_ext_ets(Eterm, byte *, struct erl_off_heap_header** ext_off_heap);
 
-#ifdef ERTS_WANT_EXTERNAL_TAGS
-ERTS_GLB_INLINE void erts_peek_dist_header(ErtsDistHeaderPeek *, byte *, Uint);
-#endif
 ERTS_GLB_INLINE void erts_free_dist_ext_copy(ErtsDistExternal *);
 ERTS_GLB_INLINE void *erts_dist_ext_trailer(ErtsDistExternal *);
 ErtsDistExternal *erts_make_dist_ext_copy(ErtsDistExternal *, Uint);
 void *erts_dist_ext_trailer(ErtsDistExternal *);
 void erts_destroy_dist_ext_copy(ErtsDistExternal *);
+
+#define ERTS_PREP_DIST_EXT_FAILED       (-1)
+#define ERTS_PREP_DIST_EXT_SUCCESS      (0)
+#define ERTS_PREP_DIST_EXT_CLOSED       (1)
+
 int erts_prepare_dist_ext(ErtsDistExternal *, byte *, Uint,
-			  DistEntry *, ErtsAtomCache *);
+			  DistEntry *, ErtsAtomCache *, Uint32 *);
 Sint erts_decode_dist_ext_size(ErtsDistExternal *);
 Eterm erts_decode_dist_ext(ErtsHeapFactory* factory, ErtsDistExternal *);
 
@@ -202,23 +195,9 @@ void erts_binary2term_abort(ErtsBinary2TermState *);
 Eterm erts_binary2term_create(ErtsBinary2TermState *, ErtsHeapFactory*);
 int erts_debug_max_atom_out_cache_index(void);
 int erts_debug_atom_to_out_cache_index(Eterm);
-
+void transcode_free_ctx(DistEntry* dep);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
-#ifdef ERTS_WANT_EXTERNAL_TAGS
-ERTS_GLB_INLINE void
-erts_peek_dist_header(ErtsDistHeaderPeek *dhpp, byte *ext, Uint sz)
-{
-    if (ext[0] == VERSION_MAGIC
-	|| ext[1] != DIST_HEADER
-	|| sz < (1+1+1))
-	dhpp->have_header = 0;
-    else {
-	dhpp->have_header = 1;
-	dhpp->cache_entries = (int) get_int8(&ext[2]);
-    }
-}
-#endif
 
 ERTS_GLB_INLINE void
 erts_free_dist_ext_copy(ErtsDistExternal *edep)
diff --git a/erts/emulator/beam/float_instrs.tab b/erts/emulator/beam/float_instrs.tab
new file mode 100644
index 0000000000..3d4db77892
--- /dev/null
+++ b/erts/emulator/beam/float_instrs.tab
@@ -0,0 +1,88 @@
+// -*- c -*-
+//
+// %CopyrightBegin%
+//
+// Copyright Ericsson AB 2017. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// %CopyrightEnd%
+//
+
+LOAD_DOUBLE(Src, Dst) {
+    GET_DOUBLE($Src, *(FloatDef *) &$Dst);
+}
+
+fload(Reg, Dst) {
+    $LOAD_DOUBLE($Reg, $Dst);
+}
+
+fstore(Float, Dst) {
+    PUT_DOUBLE(*((FloatDef *) &$Float), HTOP);
+    $Dst = make_float(HTOP);
+    HTOP += FLOAT_SIZE_OBJECT;
+}
+
+fconv(Src, Dst) {
+    Eterm src = $Src;
+
+    if (is_small(src)) {
+        $Dst = (double) signed_val(src);
+    } else if (is_big(src)) {
+        if (big_to_double(src, &$Dst) < 0) {
+            $BADARITH0();
+        }
+    } else if (is_float(src)) {
+        $LOAD_DOUBLE(src, $Dst);
+    } else {
+        $BADARITH0();
+    }
+}
+
+FLOAT_OP(Src1, OP, Src2, Dst) {
+    ERTS_NO_FPE_CHECK_INIT(c_p);
+    $Dst = $Src1 $OP $Src2;
+    ERTS_NO_FPE_ERROR(c_p, $Dst, $BADARITH0());
+}
+
+i_fadd(Src1, Src2, Dst) {
+    $FLOAT_OP($Src1, +, $Src2, $Dst);
+}
+
+i_fsub(Src1, Src2, Dst) {
+    $FLOAT_OP($Src1, -, $Src2, $Dst);
+}
+
+i_fmul(Src1, Src2, Dst) {
+    $FLOAT_OP($Src1, *, $Src2, $Dst);
+}
+
+i_fdiv(Src1, Src2, Dst) {
+    $FLOAT_OP($Src1, /, $Src2, $Dst);
+}
+
+i_fnegate(Src, Dst) {
+    ERTS_NO_FPE_CHECK_INIT(c_p);
+    $Dst = -$Src;
+    ERTS_NO_FPE_ERROR(c_p, $Dst, $BADARITH0());
+}
+
+%unless NO_FPE_SIGNALS
+fclearerror() {
+    ERTS_FP_CHECK_INIT(c_p);
+}
+
+i_fcheckerror() {
+    ERTS_FP_ERROR(c_p, freg[0].fd, $BADARITH0());
+}
+%endif
diff --git a/erts/emulator/beam/global.h b/erts/emulator/beam/global.h
index 9505942307..09207364eb 100644
--- a/erts/emulator/beam/global.h
+++ b/erts/emulator/beam/global.h
@@ -85,7 +85,7 @@ struct enif_resource_type_t
 
 typedef struct
 {
-    erts_smp_mtx_t lock;
+    erts_mtx_t lock;
     ErtsMonitor* root;
     int pending_failed_fire;
     int is_dying;
@@ -128,10 +128,8 @@ extern Eterm erts_nif_call_function(Process *p, Process *tracee,
                                     struct enif_func_t *,
                                     int argc, Eterm *argv);
 
-#ifdef ERTS_DIRTY_SCHEDULERS
 int erts_call_dirty_nif(ErtsSchedulerData *esdp, Process *c_p,
 			BeamInstr *I, Eterm *reg);
-#endif /* ERTS_DIRTY_SCHEDULERS */
 
 
 /* Driver handle (wrapper for old plain handle) */
@@ -183,9 +181,9 @@ typedef struct {
     void         *handle;             /* Handle for DLL or SO (for dyn. drivers). */
     DE_ProcEntry *procs;              /* List of pids that have loaded this driver,
 				         or that wait for it to change state */
-    erts_smp_refc_t  refc;                /* Number of ports/processes having
+    erts_refc_t  refc;                /* Number of ports/processes having
 					 references to the driver */
-    erts_smp_atomic32_t port_count;   /* Number of ports using the driver */
+    erts_atomic32_t port_count;   /* Number of ports using the driver */
     Uint         flags;               /* ERL_DE_FL_KILL_PORTS */
     int          status;              /* ERL_DE_xxx */
     char         *full_path;          /* Full path of the driver */
@@ -209,9 +207,7 @@ struct erts_driver_t_ {
     } version;
     int flags;
     DE_Handle *handle;
-#ifdef ERTS_SMP
-    erts_smp_mtx_t *lock;
-#endif
+    erts_mtx_t *lock;
     ErlDrvEntry *entry;
     ErlDrvData (*start)(ErlDrvPort port, char *command, SysDriverOpts* opts);
     void (*stop)(ErlDrvData drv_data);
@@ -226,8 +222,6 @@ struct erts_driver_t_ {
 			 char *buf, ErlDrvSizeT len,
 			 char **rbuf, ErlDrvSizeT rlen, /* Might be NULL */
 			 unsigned int *flags);
-    void (*event)(ErlDrvData drv_data, ErlDrvEvent event,
-		  ErlDrvEventData event_data);
     void (*ready_input)(ErlDrvData drv_data, ErlDrvEvent event); 
     void (*ready_output)(ErlDrvData drv_data, ErlDrvEvent event);  
     void (*timeout)(ErlDrvData drv_data);
@@ -238,7 +232,7 @@ struct erts_driver_t_ {
 };
 
 extern erts_driver_t *driver_list;
-extern erts_smp_rwmtx_t erts_driver_list_lock;
+extern erts_rwmtx_t erts_driver_list_lock;
 
 extern void erts_ddll_init(void);
 extern void erts_ddll_lock_driver(DE_Handle *dh, char *name);
@@ -299,7 +293,7 @@ extern Eterm node_cookie;
 extern Uint display_items;	/* no of items to display in traces etc */
 
 extern int erts_backtrace_depth;
-extern erts_smp_atomic32_t erts_max_gen_gcs;
+extern erts_atomic32_t erts_max_gen_gcs;
 
 extern int bif_reductions;      /* reductions + fcalls (when doing call_bif) */
 extern int stackdump_on_exit;
@@ -909,13 +903,11 @@ typedef struct ErtsLiteralArea_ {
 #define ERTS_LITERAL_AREA_ALLOC_SIZE(N) \
     (sizeof(ErtsLiteralArea) + sizeof(Eterm)*((N) - 1))
 
-extern erts_smp_atomic_t erts_copy_literal_area__;
+extern erts_atomic_t erts_copy_literal_area__;
 #define ERTS_COPY_LITERAL_AREA()					\
-    ((ErtsLiteralArea *) erts_smp_atomic_read_nob(&erts_copy_literal_area__))
+    ((ErtsLiteralArea *) erts_atomic_read_nob(&erts_copy_literal_area__))
 extern Process *erts_literal_area_collector;
-#ifdef ERTS_DIRTY_SCHEDULERS
 extern Process *erts_dirty_process_code_checker;
-#endif
 
 extern Process *erts_code_purger;
 
@@ -1112,7 +1104,6 @@ void erts_save_stacktrace(Process* p, struct StackTrace* s, int depth);
 typedef struct {
     Eterm delay_time;
     int context_reds;
-    int input_reds;
 } ErtsModifiedTimings;
 
 extern Export *erts_delay_trap;
@@ -1130,18 +1121,12 @@ extern ErtsModifiedTimings erts_modified_timings[];
 extern int erts_no_line_info;
 extern Eterm erts_error_logger_warnings;
 extern int erts_initialized;
-#if defined(USE_THREADS) && !defined(ERTS_SMP)
-extern erts_tid_t erts_main_thread;
-#endif
 extern int erts_compat_rel;
 extern int erts_use_sender_punish;
 void erl_start(int, char**);
 void erts_usage(void);
 Eterm erts_preloaded(Process* p);
 
-#ifndef ERTS_SMP
-extern void *erts_scheduler_stack_limit;
-#endif
 
 /* erl_md5.c */
 
@@ -1185,7 +1170,7 @@ void erts_emergency_close_ports(void);
 void erts_ref_to_driver_monitor(Eterm ref, ErlDrvMonitor *mon);
 Eterm erts_driver_monitor_to_ref(Eterm* hp, const ErlDrvMonitor *mon);
 
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_COUNT)
+#if defined(ERTS_ENABLE_LOCK_COUNT)
 void erts_lcnt_update_driver_locks(int enable);
 void erts_lcnt_update_port_locks(int enable);
 #endif
@@ -1397,7 +1382,7 @@ Uint erts_current_reductions(Process* current, Process *p);
 
 int erts_print_system_version(fmtfn_t to, void *arg, Process *c_p);
 
-int erts_hibernate(Process* c_p, Eterm module, Eterm function, Eterm args, Eterm* reg);
+int erts_hibernate(Process* c_p, Eterm* reg);
 
 ERTS_GLB_FORCE_INLINE int erts_is_literal(Eterm tptr, Eterm *ptr);
 
diff --git a/erts/emulator/beam/index.c b/erts/emulator/beam/index.c
index 7bf1a032c1..be1771b037 100644
--- a/erts/emulator/beam/index.c
+++ b/erts/emulator/beam/index.c
@@ -98,7 +98,7 @@ index_put_entry(IndexTable* t, void* tmpl)
      * Do a write barrier here to allow readers to do lock free iteration.
      * erts_index_num_entries() does matching read barrier.
      */
-    ERTS_SMP_WRITE_MEMORY_BARRIER;
+    ERTS_THR_WRITE_MEMORY_BARRIER;
     t->entries++;
 
     return p;
diff --git a/erts/emulator/beam/index.h b/erts/emulator/beam/index.h
index 6c07571df6..30bc6a1121 100644
--- a/erts/emulator/beam/index.h
+++ b/erts/emulator/beam/index.h
@@ -88,7 +88,7 @@ ERTS_GLB_INLINE int erts_index_num_entries(IndexTable* t)
      * on tables where entries are never erased.
      * index_put_entry() does matching write barrier.
      */
-    ERTS_SMP_READ_MEMORY_BARRIER;
+    ERTS_THR_READ_MEMORY_BARRIER;
     return ret;
 }
 
diff --git a/erts/emulator/beam/instrs.tab b/erts/emulator/beam/instrs.tab
new file mode 100644
index 0000000000..b92152238e
--- /dev/null
+++ b/erts/emulator/beam/instrs.tab
@@ -0,0 +1,938 @@
+// -*- c -*-
+//
+// %CopyrightBegin%
+//
+// Copyright Ericsson AB 2017. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// %CopyrightEnd%
+//
+
+// Stack manipulation instructions
+
+allocate(NeedStack, Live) {
+    $AH($NeedStack, 0, $Live);
+}
+
+allocate_heap(NeedStack, NeedHeap, Live) {
+    $AH($NeedStack, $NeedHeap, $Live);
+}
+
+allocate_init(NeedStack, Live, Y) {
+    $AH($NeedStack, 0, $Live);
+    make_blank($Y);
+}
+
+allocate_zero(NeedStack, Live) {
+    Eterm* ptr;
+    int i = $NeedStack;
+    $AH(i, 0, $Live);
+    for (ptr = E + i; ptr > E; ptr--) {
+	 make_blank(*ptr);
+    }
+}
+
+allocate_heap_zero(NeedStack, NeedHeap, Live) {
+    Eterm* ptr;
+    int i = $NeedStack;
+    $AH(i, $NeedHeap, $Live);
+    for (ptr = E + i; ptr > E; ptr--) {
+        make_blank(*ptr);
+    }
+}
+
+// This instruction is probably never used (because it is combined with a
+// a return). However, a future compiler might for some reason emit a
+// deallocate not followed by a return, and that should work.
+
+deallocate(Deallocate) {
+    //| -no_prefetch
+    SET_CP(c_p, (BeamInstr *) cp_val(*E));
+    E = ADD_BYTE_OFFSET(E, $Deallocate);
+}
+
+deallocate_return(Deallocate) {
+    //| -no_next
+    int words_to_pop = $Deallocate;
+    SET_I((BeamInstr *) cp_val(*E));
+    E = ADD_BYTE_OFFSET(E, words_to_pop);
+    CHECK_TERM(x(0));
+    DispatchReturn;
+}
+
+move_deallocate_return(Src, Deallocate) {
+    x(0) = $Src;
+    $deallocate_return($Deallocate);
+}
+
+// Call instructions
+
+DISPATCH_REL(CallDest) {
+    //| -no_next
+    $SET_I_REL($CallDest);
+    DTRACE_LOCAL_CALL(c_p, erts_code_to_codemfa(I));
+    Dispatch();
+}
+
+DISPATCH_ABS(CallDest) {
+    //| -no_next
+    SET_I((BeamInstr *) $CallDest);
+    DTRACE_LOCAL_CALL(c_p, erts_code_to_codemfa(I));
+    Dispatch();
+}
+
+i_call(CallDest) {
+    SET_CP(c_p, $NEXT_INSTRUCTION);
+    $DISPATCH_REL($CallDest);
+}
+
+move_call(Src, CallDest) {
+    x(0) = $Src;
+    SET_CP(c_p, $NEXT_INSTRUCTION);
+    $DISPATCH_REL($CallDest);
+}
+
+i_call_last(CallDest, Deallocate) {
+    $deallocate($Deallocate);
+    $DISPATCH_REL($CallDest);
+}
+
+move_call_last(Src, CallDest, Deallocate) {
+    x(0) = $Src;
+    $i_call_last($CallDest, $Deallocate);
+}
+
+i_call_only(CallDest) {
+    $DISPATCH_REL($CallDest);
+}
+
+move_call_only(Src, CallDest) {
+    x(0) = $Src;
+    $i_call_only($CallDest);
+}
+
+DISPATCHX(Dest) {
+    //| -no_next
+    DTRACE_GLOBAL_CALL_FROM_EXPORT(c_p, $Dest);
+    // Dispatchx assumes the Export* is in Arg(0)
+    I = (&$Dest) - 1;
+    Dispatchx();
+}
+
+i_call_ext(Dest) {
+    SET_CP(c_p, $NEXT_INSTRUCTION);
+    $DISPATCHX($Dest);
+}
+
+i_move_call_ext(Src, Dest) {
+    x(0) = $Src;
+    $i_call_ext($Dest);
+}
+
+i_call_ext_only(Dest) {
+    $DISPATCHX($Dest);
+}
+
+i_move_call_ext_only(Dest, Src) {
+    x(0) = $Src;
+    $i_call_ext_only($Dest);
+}
+
+i_call_ext_last(Dest, Deallocate) {
+    $deallocate($Deallocate);
+    $DISPATCHX($Dest);
+}
+
+i_move_call_ext_last(Dest, StackOffset, Src) {
+    x(0) = $Src;
+    $i_call_ext_last($Dest, $StackOffset);
+}
+
+APPLY(I, Deallocate, Next) {
+    //| -no_next
+    HEAVY_SWAPOUT;
+    $Next = apply(c_p, reg, $I, $Deallocate);
+    HEAVY_SWAPIN;
+}
+
+HANDLE_APPLY_ERROR() {
+    I = handle_error(c_p, I, reg, &bif_export[BIF_apply_3]->info.mfa);
+    goto post_error_handling;
+}
+
+i_apply() {
+    BeamInstr *next;
+    $APPLY(NULL, 0, next);
+    if (ERTS_LIKELY(next != NULL)) {
+        SET_CP(c_p, $NEXT_INSTRUCTION);
+        $DISPATCH_ABS(next);
+    }
+    $HANDLE_APPLY_ERROR();
+}
+
+i_apply_last(Deallocate) {
+    BeamInstr *next;
+    $APPLY(I, $Deallocate, next);
+    if (ERTS_LIKELY(next != NULL)) {
+        $deallocate($Deallocate);
+        $DISPATCH_ABS(next);
+    }
+    $HANDLE_APPLY_ERROR();
+}
+
+i_apply_only() {
+    BeamInstr *next;
+    $APPLY(I, 0, next);
+    if (ERTS_LIKELY(next != NULL)) {
+        $DISPATCH_ABS(next);
+    }
+    $HANDLE_APPLY_ERROR();
+}
+
+FIXED_APPLY(Arity, I, Deallocate, Next) {
+    //| -no_next
+    HEAVY_SWAPOUT;
+    $Next = fixed_apply(c_p, reg, $Arity, $I, $Deallocate);
+    HEAVY_SWAPIN;
+}
+
+apply(Arity) {
+    BeamInstr *next;
+    $FIXED_APPLY($Arity, NULL, 0, next);
+    if (ERTS_LIKELY(next != NULL)) {
+        SET_CP(c_p, $NEXT_INSTRUCTION);
+        $DISPATCH_ABS(next);
+    }
+    $HANDLE_APPLY_ERROR();
+}
+
+apply_last(Arity, Deallocate) {
+    BeamInstr *next;
+    $FIXED_APPLY($Arity, I, $Deallocate, next);
+    if (ERTS_LIKELY(next != NULL)) {
+        $deallocate($Deallocate);
+        $DISPATCH_ABS(next);
+    }
+    $HANDLE_APPLY_ERROR();
+}
+
+APPLY_FUN(Next) {
+    HEAVY_SWAPOUT;
+    $Next = apply_fun(c_p, r(0), x(1), reg);
+    HEAVY_SWAPIN;
+}
+
+HANDLE_APPLY_FUN_ERROR() {
+     goto find_func_info;
+}
+
+DISPATCH_FUN(I) {
+    SET_I($I);
+    Dispatchfun();
+}
+
+i_apply_fun() {
+    BeamInstr *next;
+    $APPLY_FUN(next);
+    if (ERTS_LIKELY(next != NULL)) {
+        SET_CP(c_p, $NEXT_INSTRUCTION);
+        $DISPATCH_FUN(next);
+    }
+    $HANDLE_APPLY_FUN_ERROR();
+}
+
+i_apply_fun_last(Deallocate) {
+    BeamInstr *next;
+    $APPLY_FUN(next);
+    if (ERTS_LIKELY(next != NULL)) {
+        $deallocate($Deallocate);
+        $DISPATCH_FUN(next);
+    }
+    $HANDLE_APPLY_FUN_ERROR();
+}
+
+i_apply_fun_only() {
+    BeamInstr *next;
+    $APPLY_FUN(next);
+    if (ERTS_LIKELY(next != NULL)) {
+        $DISPATCH_FUN(next);
+    }
+    $HANDLE_APPLY_FUN_ERROR();
+}
+
+CALL_FUN(Fun, Next) {
+    //| -no_next
+    HEAVY_SWAPOUT;
+    $Next = call_fun(c_p, $Fun, reg, THE_NON_VALUE);
+    HEAVY_SWAPIN;
+}
+
+i_call_fun(Fun) {
+    BeamInstr *next;
+    $CALL_FUN($Fun, next);
+    if (ERTS_LIKELY(next != NULL)) {
+        SET_CP(c_p, $NEXT_INSTRUCTION);
+        $DISPATCH_FUN(next);
+    }
+    $HANDLE_APPLY_FUN_ERROR();
+}
+
+i_call_fun_last(Fun, Deallocate) {
+    BeamInstr *next;
+    $CALL_FUN($Fun, next);
+    if (ERTS_LIKELY(next != NULL)) {
+        $deallocate($Deallocate);
+        $DISPATCH_FUN(next);
+    }
+    $HANDLE_APPLY_FUN_ERROR();
+}
+
+return() {
+    SET_I(c_p->cp);
+    DTRACE_RETURN_FROM_PC(c_p);
+
+    /*
+     * We must clear the CP to make sure that a stale value do not
+     * create a false module dependcy preventing code upgrading.
+     * It also means that we can use the CP in stack backtraces.
+     */
+    c_p->cp = 0;
+    CHECK_TERM(r(0));
+    HEAP_SPACE_VERIFIED(0);
+    DispatchReturn;
+}
+
+get_list(Src, Hd, Tl) {
+    Eterm* tmp_ptr = list_val($Src);
+    Eterm hd, tl;
+    hd = CAR(tmp_ptr);
+    tl = CDR(tmp_ptr);
+    $Hd = hd;
+    $Tl = tl;
+}
+
+i_get(Src, Dst) {
+    $Dst = erts_pd_hash_get(c_p, $Src);
+}
+
+i_get_hash(Src, Hash, Dst) {
+    $Dst = erts_pd_hash_get_with_hx(c_p, $Hash, $Src);
+}
+
+i_get_tuple_element(Src, Element, Dst) {
+    Eterm* src = ADD_BYTE_OFFSET(tuple_val($Src), $Element);
+    $Dst = *src;
+}
+
+i_get_tuple_element2(Src, Element, Dst) {
+    Eterm* src;
+    Eterm* dst;
+    Eterm E1, E2;
+    src = ADD_BYTE_OFFSET(tuple_val($Src), $Element);
+    dst = &($Dst);
+    E1 = src[0];
+    E2 = src[1];
+    dst[0] = E1;
+    dst[1] = E2;
+}
+
+i_get_tuple_element2y(Src, Element, D1, D2) {
+    Eterm* src;
+    Eterm E1, E2;
+    src = ADD_BYTE_OFFSET(tuple_val($Src), $Element);
+    E1 = src[0];
+    E2 = src[1];
+    $D1 = E1;
+    $D2 = E2;
+}
+
+i_get_tuple_element3(Src, Element, Dst) {
+    Eterm* src;
+    Eterm* dst;
+    Eterm E1, E2, E3;
+    src = ADD_BYTE_OFFSET(tuple_val($Src), $Element);
+    dst = &($Dst);
+    E1 = src[0];
+    E2 = src[1];
+    E3 = src[2];
+    dst[0] = E1;
+    dst[1] = E2;
+    dst[2] = E3;
+}
+
+i_element := element_group.fetch.execute;
+
+
+element_group.head() {
+    Eterm element_tuple;
+}
+
+element_group.fetch(Src) {
+    element_tuple = $Src;
+}
+
+element_group.execute(Fail, Index, Dst) {
+    Eterm element_index = $Index;
+    if (ERTS_LIKELY(is_small(element_index) && is_tuple(element_tuple))) {
+        Eterm* tp = tuple_val(element_tuple);
+
+        if ((signed_val(element_index) >= 1) &&
+            (signed_val(element_index) <= arityval(*tp))) {
+            $Dst = tp[signed_val(element_index)];
+            $NEXT0();
+        }
+    }
+    c_p->freason = BADARG;
+    $BIF_ERROR_ARITY_2($Fail, BIF_element_2, element_index, element_tuple);
+}
+
+i_fast_element := fast_element_group.fetch.execute;
+
+fast_element_group.head() {
+    Eterm fast_element_tuple;
+}
+
+fast_element_group.fetch(Src) {
+    fast_element_tuple = $Src;
+}
+
+fast_element_group.execute(Fail, Index, Dst) {
+    if (ERTS_LIKELY(is_tuple(fast_element_tuple))) {
+        Eterm* tp = tuple_val(fast_element_tuple);
+        Eterm pos = $Index;	/* Untagged integer >= 1 */
+        if (pos <= arityval(*tp)) {
+            $Dst = tp[pos];
+            $NEXT0();
+	}
+    }
+    c_p->freason = BADARG;
+    $BIF_ERROR_ARITY_2($Fail, BIF_element_2, make_small($Index), fast_element_tuple);
+}
+
+init(Y) {
+    make_blank($Y);
+}
+
+init2(Y1, Y2) {
+    make_blank($Y1);
+    make_blank($Y2);
+}
+
+init3(Y1, Y2, Y3) {
+    make_blank($Y1);
+    make_blank($Y2);
+    make_blank($Y3);
+}
+
+i_make_fun(FunP, NumFree) {
+    HEAVY_SWAPOUT;
+    x(0) = new_fun(c_p, reg, (ErlFunEntry *) $FunP, $NumFree);
+    HEAVY_SWAPIN;
+}
+
+i_trim(Words) {
+    Uint cp = E[0];
+    E += $Words;
+    E[0] = cp;
+}
+
+move(Src, Dst) {
+    $Dst = $Src;
+}
+
+move3(S1, D1, S2, D2, S3, D3) {
+    $D1 = $S1;
+    $D2 = $S2;
+    $D3 = $S3;
+}
+
+move_dup(Src, D1, D2) {
+    $D1 = $D2 = $Src;
+}
+
+move2_par(S1, D1, S2, D2) {
+    Eterm V1, V2;
+    V1 = $S1;
+    V2 = $S2;
+    $D1 = V1;
+    $D2 = V2;
+}
+
+move_shift(Src, SD, D) {
+    Eterm V;
+    V = $Src;
+    $D = $SD;
+    $SD = V;
+}
+
+move_window3(S1, S2, S3, D) {
+    Eterm xt0, xt1, xt2;
+    Eterm* y = &$D;
+    xt0  = $S1;
+    xt1  = $S2;
+    xt2  = $S3;
+    y[0] = xt0;
+    y[1] = xt1;
+    y[2] = xt2;
+}
+
+move_window4(S1, S2, S3, S4, D) {
+    Eterm xt0, xt1, xt2, xt3;
+    Eterm* y = &$D;
+    xt0  = $S1;
+    xt1  = $S2;
+    xt2  = $S3;
+    xt3  = $S4;
+    y[0] = xt0;
+    y[1] = xt1;
+    y[2] = xt2;
+    y[3] = xt3;
+}
+
+move_window5(S1, S2, S3, S4, S5, D) {
+    Eterm xt0, xt1, xt2, xt3, xt4;
+    Eterm *y = &$D;
+    xt0  = $S1;
+    xt1  = $S2;
+    xt2  = $S3;
+    xt3  = $S4;
+    xt4  = $S5;
+    y[0] = xt0;
+    y[1] = xt1;
+    y[2] = xt2;
+    y[3] = xt3;
+    y[4] = xt4;
+}
+
+move_return(Src) {
+    //| -no_next
+    x(0) = $Src;
+    SET_I(c_p->cp);
+    c_p->cp = 0;
+    DispatchReturn;
+}
+
+move_x1(Src) {
+    x(1) = $Src;
+}
+
+move_x2(Src) {
+    x(2) = $Src;
+}
+
+node(Dst) {
+    $Dst = erts_this_node->sysname;
+}
+
+put_list(Hd, Tl, Dst) {
+    HTOP[0] = $Hd;
+    HTOP[1] = $Tl;
+    $Dst = make_list(HTOP);
+    HTOP += 2;
+}
+
+update_list(Hd, Dst) {
+    HTOP[0] = $Hd;
+    HTOP[1] = $Dst;
+    $Dst = make_list(HTOP);
+    HTOP += 2;
+}
+
+i_put_tuple := i_put_tuple.make.fill;
+
+i_put_tuple.make(Dst) {
+    $Dst = make_tuple(HTOP);
+}
+
+i_put_tuple.fill(Arity) {
+    Eterm* hp = HTOP;
+    Eterm arity = $Arity;
+
+    //| -no_next
+    *hp++ = make_arityval(arity);
+    I = $NEXT_INSTRUCTION;
+    do {
+        Eterm term = *I++;
+        switch (loader_tag(term)) {
+        case LOADER_X_REG:
+            *hp++ = x(loader_x_reg_index(term));
+            break;
+        case LOADER_Y_REG:
+            *hp++ = y(loader_y_reg_index(term));
+            break;
+        default:
+            *hp++ = term;
+            break;
+        }
+    } while (--arity != 0);
+    HTOP = hp;
+    ASSERT(VALID_INSTR(* (Eterm *)I));
+    Goto(*I);
+}
+
+self(Dst) {
+    $Dst = c_p->common.id;
+}
+
+set_tuple_element(Element, Tuple, Offset) {
+    Eterm* p;
+
+    ASSERT(is_tuple($Tuple));
+    p = (Eterm *) ((unsigned char *) tuple_val($Tuple) + $Offset);
+    *p = $Element;
+}
+
+swap(R1, R2) {
+    Eterm V = $R1;
+    $R1 = $R2;
+    $R2 = V;
+}
+
+swap_temp(R1, R2, Tmp) {
+    Eterm V = $R1;
+    $R1 = $R2;
+    $R2 = $Tmp = V;
+}
+
+test_heap(Nh, Live) {
+    $GC_TEST(0, $Nh, $Live);
+}
+
+test_heap_1_put_list(Nh, Reg) {
+    $test_heap($Nh, 1);
+    $put_list($Reg, x(0), x(0));
+}
+
+is_integer_allocate(Fail, Src, NeedStack, Live) {
+    //| -no_prefetch
+    $is_integer($Fail, $Src);
+    $AH($NeedStack, 0, $Live);
+}
+
+is_nonempty_list(Fail, Src) {
+    //| -no_prefetch
+    if (is_not_list($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_nonempty_list_test_heap(Fail, Need, Live) {
+    //| -no_prefetch
+    $is_nonempty_list($Fail, x(0));
+    $test_heap($Need, $Live);
+}
+
+is_nonempty_list_allocate(Fail, Src, Need, Live) {
+    //| -no_prefetch
+    $is_nonempty_list($Fail, $Src);
+    $AH($Need, 0, $Live);
+}
+
+is_nonempty_list_get_list(Fail, Src, Hd, Tl) {
+    //| -no_prefetch
+    $is_nonempty_list($Fail, $Src);
+    $get_list($Src, $Hd, $Tl);
+}
+
+jump(Fail) {
+    $JUMP($Fail);
+}
+
+move_jump(Fail, Src) {
+    x(0) = $Src;
+    $jump($Fail);
+}
+
+//
+// Test instructions.
+//
+
+is_atom(Fail, Src) {
+    if (is_not_atom($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_boolean(Fail, Src) {
+    if (($Src) != am_true && ($Src) != am_false) {
+        $FAIL($Fail);
+    }
+}
+
+is_binary(Fail, Src) {
+    if (is_not_binary($Src) || binary_bitsize($Src) != 0) {
+        $FAIL($Fail);
+    }
+}
+
+is_bitstring(Fail, Src) {
+  if (is_not_binary($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_float(Fail, Src) {
+    if (is_not_float($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_function(Fail, Src) {
+    if ( !(is_any_fun($Src)) ) {
+        $FAIL($Fail);
+    }
+}
+
+is_function2(Fail, Fun, Arity) {
+    if (erl_is_function(c_p, $Fun, $Arity) != am_true ) {
+        $FAIL($Fail);
+    }
+}
+
+is_integer(Fail, Src) {
+    if (is_not_integer($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_list(Fail, Src) {
+    if (is_not_list($Src) && is_not_nil($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_map(Fail, Src) {
+    if (is_not_map($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_nil(Fail, Src) {
+    if (is_not_nil($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_number(Fail, Src) {
+    if (is_not_integer($Src) && is_not_float($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_pid(Fail, Src) {
+    if (is_not_pid($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_port(Fail, Src) {
+    if (is_not_port($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_reference(Fail, Src) {
+    if (is_not_ref($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_tagged_tuple(Fail, Src, Arityval, Tag) {
+    Eterm term = $Src;
+    if (!(BEAM_IS_TUPLE(term) &&
+          (tuple_val(term))[0] == $Arityval &&
+          (tuple_val(term))[1] == $Tag)) {
+        $FAIL($Fail);
+    }
+}
+
+is_tuple(Fail, Src) {
+    if (is_not_tuple($Src)) {
+        $FAIL($Fail);
+    }
+}
+
+is_tuple_of_arity(Fail, Src, Arityval) {
+    Eterm term = $Src;
+    if (!(BEAM_IS_TUPLE(term) && *tuple_val(term) == $Arityval)) {
+        $FAIL($Fail);
+    }
+}
+
+test_arity(Fail, Pointer, Arity) {
+    if (*tuple_val($Pointer) != $Arity) {
+        $FAIL($Fail);
+    }
+}
+
+i_is_eq_exact_immed(Fail, X, Y) {
+    if ($X != $Y) {
+        $FAIL($Fail);
+    }
+}
+
+i_is_ne_exact_immed(Fail, X, Y) {
+    if ($X == $Y) {
+        $FAIL($Fail);
+    }
+}
+
+is_eq_exact(Fail, X, Y) {
+    if (!EQ($X, $Y)) {
+        $FAIL($Fail);
+    }
+}
+
+i_is_eq_exact_literal(Fail, Src, Literal) {
+    Eterm src = $Src;
+    if (is_immed(src) || !eq(src, $Literal)) {
+        $FAIL($Fail);
+    }
+}
+
+is_ne_exact(Fail, X, Y) {
+    if (EQ($X, $Y)) {
+        $FAIL($Fail);
+    }
+}
+
+i_is_ne_exact_literal(Fail, Src, Literal) {
+    Eterm src = $Src;
+    if (!is_immed(src) && eq(src, $Literal)) {
+        $FAIL($Fail);
+    }
+}
+
+is_eq(Fail, X, Y) {
+    CMP_EQ_ACTION($X, $Y, $FAIL($Fail));
+}
+
+is_ne(Fail, X, Y) {
+    CMP_NE_ACTION($X, $Y, $FAIL($Fail));
+}
+
+is_lt(Fail, X, Y) {
+    CMP_LT_ACTION($X, $Y, $FAIL($Fail));
+}
+
+is_ge(Fail, X, Y) {
+    CMP_GE_ACTION($X, $Y, $FAIL($Fail));
+}
+
+badarg(Fail) {
+    $BADARG($Fail);
+    //| -no_next;
+}
+
+badmatch(Src) {
+    c_p->fvalue = $Src;
+    c_p->freason = BADMATCH;
+    goto find_func_info;
+    //| -no_next;
+}
+
+case_end(Src) {
+    c_p->fvalue = $Src;
+    c_p->freason = EXC_CASE_CLAUSE;
+    goto find_func_info;
+    //| -no_next;
+}
+
+if_end() {
+    c_p->freason = EXC_IF_CLAUSE;
+    goto find_func_info;
+    //| -no_next;
+}
+
+system_limit(Fail) {
+    $SYSTEM_LIMIT($Fail);
+    //| -no_next;
+}
+
+catch(Y, Fail) {
+    c_p->catches++;
+    $Y = $Fail;
+}
+
+catch_end(Y) {
+    $try_end($Y);
+    if (is_non_value(r(0))) {
+        c_p->fvalue = NIL;
+        if (x(1) == am_throw) {
+            r(0) = x(2);
+        } else {
+            if (x(1) == am_error) {
+                SWAPOUT;
+                x(2) = add_stacktrace(c_p, x(2), x(3));
+                SWAPIN;
+            }
+            /* only x(2) is included in the rootset here */
+            if (E - HTOP < 3) {
+                SWAPOUT;
+                PROCESS_MAIN_CHK_LOCKS(c_p);
+                FCALLS -= erts_garbage_collect_nobump(c_p, 3, reg+2, 1, FCALLS);
+                ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+                PROCESS_MAIN_CHK_LOCKS(c_p);
+                SWAPIN;
+            }
+            r(0) = TUPLE2(HTOP, am_EXIT, x(2));
+            HTOP += 3;
+        }
+    }
+    CHECK_TERM(r(0));
+}
+
+try_end(Y) {
+    c_p->catches--;
+    make_blank($Y);
+}
+
+try_case(Y) {
+    $try_end($Y);
+    ASSERT(is_non_value(r(0)));
+    c_p->fvalue = NIL;
+    r(0) = x(1);
+    x(1) = x(2);
+    x(2) = x(3);
+}
+
+try_case_end(Src) {
+    c_p->fvalue = $Src;
+    c_p->freason = EXC_TRY_CLAUSE;
+    goto find_func_info;
+    //| -no_next;
+}
+
+i_raise() {
+    Eterm raise_trace = x(2);
+    Eterm raise_value = x(1);
+    struct StackTrace *s;
+
+    c_p->fvalue = raise_value;
+    c_p->ftrace = raise_trace;
+    s = get_trace_from_exc(raise_trace);
+    if (s == NULL) {
+        c_p->freason = EXC_ERROR;
+    } else {
+        c_p->freason = PRIMARY_EXCEPTION(s->freason);
+    }
+    goto find_func_info;
+    //| -no_next
+}
+
+build_stacktrace() {
+    SWAPOUT;
+    x(0) = build_stacktrace(c_p, x(0));
+    SWAPIN;
+}
diff --git a/erts/emulator/beam/io.c b/erts/emulator/beam/io.c
index 3a5ddde5f4..9933c8dda4 100644
--- a/erts/emulator/beam/io.c
+++ b/erts/emulator/beam/io.c
@@ -63,10 +63,10 @@ extern ErlDrvEntry forker_driver_entry;
 extern ErlDrvEntry *driver_tab[]; /* table of static drivers, only used during initialization */
 
 erts_driver_t *driver_list; /* List of all drivers, static and dynamic. */
-erts_smp_rwmtx_t erts_driver_list_lock; /* Mutex for driver list */
-static erts_smp_tsd_key_t driver_list_lock_status_key; /*stop recursive locks when calling 
+erts_rwmtx_t erts_driver_list_lock; /* Mutex for driver list */
+static erts_tsd_key_t driver_list_lock_status_key; /*stop recursive locks when calling
 							 driver init */
-static erts_smp_tsd_key_t driver_list_last_error_key;  /* Save last DDLL error on a 
+static erts_tsd_key_t driver_list_last_error_key;  /* Save last DDLL error on a
 							  per thread basis (for BC interfaces) */
 
 ErtsPTab erts_port erts_align_attribute(ERTS_CACHE_LINE_SIZE); /* The port table */
@@ -94,17 +94,11 @@ static int init_driver(erts_driver_t *, ErlDrvEntry *, DE_Handle *);
 static void terminate_port(Port *p);
 static void pdl_init(void);
 static int driver_failure_term(ErlDrvPort ix, Eterm term, int eof);
-#ifdef ERTS_SMP
 static void driver_monitor_lock_pdl(Port *p);
 static void driver_monitor_unlock_pdl(Port *p);
 #define DRV_MONITOR_LOOKUP_PORT_LOCK_PDL(Port) erts_thr_drvport2port((Port), 1)
 #define DRV_MONITOR_LOCK_PDL(Port) driver_monitor_lock_pdl(Port)
 #define DRV_MONITOR_UNLOCK_PDL(Port) driver_monitor_unlock_pdl(Port)
-#else
-#define DRV_MONITOR_LOOKUP_PORT_LOCK_PDL(Port) erts_thr_drvport2port((Port), 0)
-#define DRV_MONITOR_LOCK_PDL(Port) /* nothing */
-#define DRV_MONITOR_UNLOCK_PDL(Port) /* nothing */
-#endif
 
 #define ERL_SMALL_IO_BIN_LIMIT (4*ERL_ONHEAP_BIN_LIMIT)
 #define SMALL_WRITE_VEC  16
@@ -122,7 +116,7 @@ static ERTS_INLINE int
 is_port_ioq_empty(Port *pp)
 {
     int res;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(pp));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(pp));
     if (!pp->port_data_lock)
 	res = (erts_ioq_size(&pp->ioq) == 0);
     else {
@@ -144,7 +138,7 @@ Uint
 erts_port_ioq_size(Port *pp)
 {
     ErlDrvSizeT res;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(pp));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(pp));
     if (!pp->port_data_lock)
 	res = erts_ioq_size(&pp->ioq);
     else {
@@ -212,14 +206,13 @@ dtrace_drvport_str(ErlDrvPort drvport, char *port_buf)
 static ERTS_INLINE void
 kill_port(Port *pp)
 {
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(pp));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(pp));
     ERTS_TRACER_CLEAR(&ERTS_TRACER(pp));
     erts_ptab_delete_element(&erts_port, &pp->common); /* Time of death */
     erts_port_task_free_port(pp);
     /* In non-smp case the port structure may have been deallocated now */
 }
 
-#ifdef ERTS_SMP
 
 #ifdef ERTS_ENABLE_LOCK_CHECK
 int
@@ -227,12 +220,11 @@ erts_lc_is_port_locked(Port *prt)
 {
     if (!prt)
 	return 0;
-    ERTS_SMP_LC_ASSERT(prt->lock);
-    return erts_smp_lc_mtx_is_locked(prt->lock);
+    ERTS_LC_ASSERT(prt->lock);
+    return erts_lc_mtx_is_locked(prt->lock);
 }
 #endif
 
-#endif /* #ifdef ERTS_SMP */
 
 static void initq(Port* prt);
 
@@ -256,25 +248,21 @@ static ERTS_INLINE void port_init_instr(Port *prt
      * Stuff that need to be initialized with the port id
      * in the instrumented case, but not in the normal case.
      */
-#ifdef ERTS_SMP
     ASSERT(prt->drv_ptr && prt->lock);
     if (!prt->drv_ptr->lock) {
         erts_mtx_init_locked(prt->lock, "port_lock", id, ERTS_LOCK_FLAGS_CATEGORY_IO);
     }
-#endif
     erts_port_task_init_sched(&prt->sched, id);
 }
 
 #if !ERTS_PORT_INIT_INSTR_NEED_ID
 static ERTS_INLINE void port_init_instr_abort(Port *prt)
 {
-#ifdef ERTS_SMP
     ASSERT(prt->drv_ptr && prt->lock);
     if (!prt->drv_ptr->lock) {
 	erts_mtx_unlock(prt->lock);
 	erts_mtx_destroy(prt->lock);
     }
-#endif
     erts_port_task_fini_sched(&prt->sched);
 }
 #endif
@@ -310,7 +298,6 @@ static Port *create_port(char *name,
     erts_aint32_t state = ERTS_PORT_SFLG_CONNECTED;
     erts_aint32_t x_pts_flgs = 0;
 
-#ifdef ERTS_SMP
     ErtsRunQueue *runq;
     if (!driver_lock) {
 	/* Align size for mutex following port struct */
@@ -318,7 +305,6 @@ static Port *create_port(char *name,
 	size += sizeof(erts_mtx_t);
     }
     else
-#endif
 	port_size = size = ERTS_ALC_DATA_ALIGN_SIZE(sizeof(Port));
 
 #ifdef DEBUG
@@ -352,7 +338,6 @@ static Port *create_port(char *name,
 	p += busy_port_queue_size;
     }
 
-#ifdef ERTS_SMP
     if (driver_lock) {
 	prt->lock = driver_lock;
 	erts_mtx_lock(driver_lock);
@@ -366,13 +351,9 @@ static Port *create_port(char *name,
         runq = erts_get_runq_current(NULL);
     else
         runq = ERTS_RUNQ_IX(0);
-    erts_smp_atomic_set_nob(&prt->run_queue, (erts_aint_t) runq);
+    erts_atomic_set_nob(&prt->run_queue, (erts_aint_t) runq);
 
     prt->xports = NULL;
-#else
-    erts_atomic32_init_nob(&prt->refc, 1);
-    prt->cleanup = 0;
-#endif
     
     erts_port_task_pre_init_sched(&prt->sched, busy_port_queue);
 
@@ -393,7 +374,7 @@ static Port *create_port(char *name,
     prt->common.u.alive.reg = NULL;
     ERTS_PTMR_INIT(prt);
     erts_port_task_handle_init(&prt->timeout_task);
-    erts_smp_atomic_init_nob(&prt->psd, (erts_aint_t) NULL);
+    erts_atomic_init_nob(&prt->psd, (erts_aint_t) NULL);
     prt->async_open_port = NULL;
     prt->drv_data = (SWord) 0;
     prt->os_pid = -1;
@@ -420,10 +401,8 @@ static Port *create_port(char *name,
 #if !ERTS_PORT_INIT_INSTR_NEED_ID
 	port_init_instr_abort(prt);
 #endif
-#ifdef ERTS_SMP
 	if (driver_lock)
 	    erts_mtx_unlock(driver_lock);
-#endif
 	if (enop)
 	    *enop = 0;
 	erts_free(ERTS_ALC_T_PORT, prt);
@@ -436,7 +415,7 @@ static Port *create_port(char *name,
 
     initq(prt);
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
     if (erts_port_schedule_all_ops)
 	x_pts_flgs |= ERTS_PTS_FLG_FORCE_SCHED;
@@ -445,29 +424,17 @@ static Port *create_port(char *name,
 	x_pts_flgs |= ERTS_PTS_FLG_PARALLELISM;
 
     if (x_pts_flgs)
-	erts_smp_atomic32_read_bor_nob(&prt->sched.flags, x_pts_flgs);
+	erts_atomic32_read_bor_nob(&prt->sched.flags, x_pts_flgs);
 
     erts_atomic32_set_relb(&prt->state, state);
     return prt;
 }
 
-#ifndef ERTS_SMP
-void
-erts_port_cleanup(Port *prt)
-{
-    if (prt->drv_ptr && prt->drv_ptr->handle)
-	erts_ddll_dereference_driver(prt->drv_ptr->handle);
-    prt->drv_ptr = NULL;
-    erts_port_dec_refc(prt);
-}
-#endif
 
 void
 erts_port_free(Port *prt)
 {
-#if defined(ERTS_SMP) || defined(DEBUG) || defined(ERTS_ENABLE_LOCK_CHECK)
     erts_aint32_t state = erts_atomic32_read_nob(&prt->state);
-#endif
     ERTS_LC_ASSERT(state & (ERTS_PORT_SFLG_INITIALIZING
 			    | ERTS_PORT_SFLG_FREE));
     ASSERT(state & ERTS_PORT_SFLG_PORT_DEBUG);
@@ -481,7 +448,6 @@ erts_port_free(Port *prt)
         prt->async_open_port = NULL;
     }
 
-#ifdef ERTS_SMP
     ASSERT(prt->lock);
     if (state & ERTS_PORT_SFLG_PORT_SPECIFIC_LOCK)
 	erts_mtx_destroy(prt->lock);
@@ -498,7 +464,6 @@ erts_port_free(Port *prt)
      */
     if (prt->drv_ptr->handle)
 	erts_ddll_dereference_driver(prt->drv_ptr->handle);
-#endif
     erts_free(ERTS_ALC_T_PORT, prt);
 }
 
@@ -533,7 +498,7 @@ erts_save_suspend_process_on_port(Port *prt, Process *process)
     int saved;
     erts_aint32_t flags;
     erts_port_task_sched_lock(&prt->sched);
-    flags = erts_smp_atomic32_read_nob(&prt->sched.flags);
+    flags = erts_atomic32_read_nob(&prt->sched.flags);
     saved = (flags & ERTS_PTS_FLGS_BUSY) && !(flags & ERTS_PTS_FLG_EXIT);
     if (saved)
 	erts_proclist_store_last(&prt->suspended, erts_proclist_create(process));
@@ -577,16 +542,16 @@ erts_open_driver(erts_driver_t* driver,	/* Pointer to driver. */
     erts_mtx_t *driver_lock = NULL;
     int cprt_flgs = 0;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
-    erts_smp_rwmtx_rlock(&erts_driver_list_lock);
+    erts_rwmtx_rlock(&erts_driver_list_lock);
     if (!driver) {
 	for (driver = driver_list; driver; driver = driver->next) {
 	    if (sys_strcmp(driver->name, name) == 0)
 		break;
 	}
 	if (!driver) { 
-	    erts_smp_rwmtx_runlock(&erts_driver_list_lock);
+	    erts_rwmtx_runlock(&erts_driver_list_lock);
 	    ERTS_OPEN_DRIVER_RET(NULL, -3, BADARG);
 	}
     }
@@ -631,19 +596,17 @@ erts_open_driver(erts_driver_t* driver,	/* Pointer to driver. */
     }
 
     if (driver == NULL || (driver != &spawn_driver && opts->exit_status)) {
-	erts_smp_rwmtx_runlock(&erts_driver_list_lock);
+	erts_rwmtx_runlock(&erts_driver_list_lock);
 	ERTS_OPEN_DRIVER_RET(NULL, -3, BADARG);
     }
 
-#ifdef ERTS_SMP
     driver_lock = driver->lock;
-#endif
 
     if (driver->handle != NULL) {
 	erts_ddll_increment_port_count(driver->handle);
 	erts_ddll_reference_driver(driver->handle);
     }
-    erts_smp_rwmtx_runlock(&erts_driver_list_lock);
+    erts_rwmtx_runlock(&erts_driver_list_lock);
 
     /*
      * We'll set up the port before calling the start function,
@@ -656,9 +619,9 @@ erts_open_driver(erts_driver_t* driver,	/* Pointer to driver. */
     port = create_port(name, driver, driver_lock, cprt_flgs, pid, &port_errno);
     if (!port) {
 	if (driver->handle) {
-	    erts_smp_rwmtx_rlock(&erts_driver_list_lock);
+	    erts_rwmtx_rlock(&erts_driver_list_lock);
 	    erts_ddll_decrement_port_count(driver->handle);
-	    erts_smp_rwmtx_runlock(&erts_driver_list_lock);
+	    erts_rwmtx_runlock(&erts_driver_list_lock);
 	    erts_ddll_dereference_driver(driver->handle);
 	}
 	if (port_errno)
@@ -726,11 +689,9 @@ erts_open_driver(erts_driver_t* driver,	/* Pointer to driver. */
 	if (IS_TRACED_FL(port, F_TRACE_SCHED_PORTS)) {
 	    trace_sched_ports_where(port, am_out, am_open);
 	}
-#ifdef ERTS_SMP
 	if (port->xports)
 	    erts_port_handle_xports(port);
 	ASSERT(!port->xports);
-#endif
     }
 
     if (error_type) {
@@ -745,9 +706,9 @@ erts_open_driver(erts_driver_t* driver,	/* Pointer to driver. */
 	    port->linebuf = NULL;
 	}
 	if (driver->handle != NULL) {
-	    erts_smp_rwmtx_rlock(&erts_driver_list_lock);
+	    erts_rwmtx_rlock(&erts_driver_list_lock);
 	    erts_ddll_decrement_port_count(driver->handle);
-	    erts_smp_rwmtx_runlock(&erts_driver_list_lock);
+	    erts_rwmtx_runlock(&erts_driver_list_lock);
 	}
 	kill_port(port);
 	erts_port_release(port);
@@ -759,7 +720,6 @@ erts_open_driver(erts_driver_t* driver,	/* Pointer to driver. */
 #undef ERTS_OPEN_DRIVER_RET
 }
 
-#ifdef ERTS_SMP
 
 struct ErtsXPortsList_ {
     ErtsXPortsList *next;
@@ -768,7 +728,6 @@ struct ErtsXPortsList_ {
 
 ERTS_SCHED_PREF_QUICK_ALLOC_IMPL(xports_list, ErtsXPortsList, 50, ERTS_ALC_T_XPORTS_LIST)
 
-#endif
 
 /*
  * Driver function to create new instances of a driver
@@ -788,7 +747,7 @@ driver_create_port(ErlDrvPort creator_port_ix, /* Creating port */
     Process *rp;
     erts_mtx_t *driver_lock = NULL;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     /* Need to be called from a scheduler thread */
     if (!erts_get_scheduler_id())
@@ -802,12 +761,12 @@ driver_create_port(ErlDrvPort creator_port_ix, /* Creating port */
     if (!rp)
 	return ERTS_INVALID_ERL_DRV_PORT;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(creator_port));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(creator_port));
 
     driver = creator_port->drv_ptr;
-    erts_smp_rwmtx_rlock(&erts_driver_list_lock);
+    erts_rwmtx_rlock(&erts_driver_list_lock);
     if (!erts_ddll_driver_ok(driver->handle)) {
-	erts_smp_rwmtx_runlock(&erts_driver_list_lock);
+	erts_rwmtx_runlock(&erts_driver_list_lock);
 	return ERTS_INVALID_ERL_DRV_PORT;
     }
 
@@ -816,35 +775,33 @@ driver_create_port(ErlDrvPort creator_port_ix, /* Creating port */
 	erts_ddll_reference_referenced_driver(driver->handle);
     }
 
-#ifdef ERTS_SMP
     driver_lock = driver->lock;
-#endif
 
-    erts_smp_rwmtx_runlock(&erts_driver_list_lock);
+    erts_rwmtx_runlock(&erts_driver_list_lock);
 
     /* Inherit parallelism flag from parent */
     if (ERTS_PTS_FLG_PARALLELISM &
-	erts_smp_atomic32_read_nob(&creator_port->sched.flags))
+	erts_atomic32_read_nob(&creator_port->sched.flags))
 	cprt_flgs |= ERTS_CREATE_PORT_FLAG_PARALLELISM;
     port = create_port(name, driver, driver_lock, cprt_flgs, pid, NULL);
     if (!port) {
 	if (driver->handle) {
-	    erts_smp_rwmtx_rlock(&erts_driver_list_lock);
+	    erts_rwmtx_rlock(&erts_driver_list_lock);
 	    erts_ddll_decrement_port_count(driver->handle);
-	    erts_smp_rwmtx_runlock(&erts_driver_list_lock);
+	    erts_rwmtx_runlock(&erts_driver_list_lock);
 	    erts_ddll_dereference_driver(driver->handle);
 	}
 	return ERTS_INVALID_ERL_DRV_PORT;
     }
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(port));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(port));
 
-    erts_smp_proc_lock(rp, ERTS_PROC_LOCK_LINK);
+    erts_proc_lock(rp, ERTS_PROC_LOCK_LINK);
     if (ERTS_PROC_IS_EXITING(rp)) {
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 	if (driver->handle) {
-	    erts_smp_rwmtx_rlock(&erts_driver_list_lock);
+	    erts_rwmtx_rlock(&erts_driver_list_lock);
 	    erts_ddll_decrement_port_count(driver->handle);
-	    erts_smp_rwmtx_runlock(&erts_driver_list_lock);
+	    erts_rwmtx_runlock(&erts_driver_list_lock);
 	}
 	kill_port(port);
 	erts_port_release(port);
@@ -853,23 +810,20 @@ driver_create_port(ErlDrvPort creator_port_ix, /* Creating port */
 
     erts_add_link(&ERTS_P_LINKS(port), LINK_PID, pid);
     erts_add_link(&ERTS_P_LINKS(rp), LINK_PID, port->common.id);
-    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+    erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 
-#ifdef ERTS_SMP
     if (!driver_lock) {
 	ErtsXPortsList *xplp = xports_list_alloc();
 	xplp->port = port;
 	xplp->next = creator_port->xports;
 	creator_port->xports = xplp;
     }
-#endif
 
     port->drv_data = (UWord) drv_data;
 
     return ERTS_Port2ErlDrvPort(port);
 }
 
-#ifdef ERTS_SMP
 int erts_port_handle_xports(Port *prt)
 {
     int reds = 0;
@@ -898,7 +852,6 @@ int erts_port_handle_xports(Port *prt)
     prt->xports = NULL;
     return reds;
 }
-#endif
 
 typedef enum {
     ERTS_TRY_IMM_DRV_CALL_OK,
@@ -945,12 +898,12 @@ try_imm_drv_call(ErtsTryImmDrvCallState *sp)
 	invalid_sched_flags |= ERTS_PTS_FLG_PARALLELISM;
 
     if (sp->pre_chk_sched_flags) {
-	sp->sched_flags = erts_smp_atomic32_read_nob(&prt->sched.flags);
+	sp->sched_flags = erts_atomic32_read_nob(&prt->sched.flags);
 	if (sp->sched_flags & invalid_sched_flags)
 	    return ERTS_TRY_IMM_DRV_CALL_INVALID_SCHED_FLAGS;
     }
 
-    if (erts_smp_port_trylock(prt) == EBUSY)
+    if (erts_port_trylock(prt) == EBUSY)
 	return ERTS_TRY_IMM_DRV_CALL_BUSY_LOCK;
 
     invalid_state = sp->state;
@@ -964,7 +917,7 @@ try_imm_drv_call(ErtsTryImmDrvCallState *sp)
     if (prof_runnable_ports)
 	erts_port_task_sched_lock(&prt->sched);
 
-    act = erts_smp_atomic32_read_nob(&prt->sched.flags);
+    act = erts_atomic32_read_nob(&prt->sched.flags);
 
     do {
 	erts_aint32_t new;
@@ -976,7 +929,7 @@ try_imm_drv_call(ErtsTryImmDrvCallState *sp)
 	}
 	exp = act;
 	new = act | ERTS_PTS_FLG_EXEC_IMM;
-	act = erts_smp_atomic32_cmpxchg_mb(&prt->sched.flags, new, exp);
+	act = erts_atomic32_cmpxchg_mb(&prt->sched.flags, new, exp);
     } while (act != exp);
     
     sp->sched_flags = act;
@@ -998,14 +951,14 @@ try_imm_drv_call(ErtsTryImmDrvCallState *sp)
 	    profile_runnable_proc(c_p, am_inactive);
 
 	reds_left_in = ERTS_BIF_REDS_LEFT(c_p);
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
     }
 
     ASSERT(0 <= reds_left_in && reds_left_in <= CONTEXT_REDS);
     sp->reds_left_in = reds_left_in;
     prt->reds = CONTEXT_REDS - reds_left_in;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     if (prof_runnable_ports | IS_TRACED_FL(prt, F_TRACE_SCHED_PORTS)) {
 	if (prof_runnable_ports && !(act & (ERTS_PTS_FLG_IN_RUNQ|ERTS_PTS_FLG_EXEC)))
@@ -1043,9 +996,9 @@ finalize_imm_drv_call(ErtsTryImmDrvCallState *sp)
     if (prof_runnable_ports)
 	erts_port_task_sched_lock(&prt->sched);
 
-    act = erts_smp_atomic32_read_band_mb(&prt->sched.flags,
+    act = erts_atomic32_read_band_mb(&prt->sched.flags,
 					 ~ERTS_PTS_FLG_EXEC_IMM);
-    ERTS_SMP_LC_ASSERT(act & ERTS_PTS_FLG_EXEC_IMM);
+    ERTS_LC_ASSERT(act & ERTS_PTS_FLG_EXEC_IMM);
 
     if (prof_runnable_ports | IS_TRACED_FL(prt, F_TRACE_SCHED_PORTS)) {
 	if (IS_TRACED_FL(prt, F_TRACE_SCHED_PORTS))
@@ -1060,7 +1013,7 @@ finalize_imm_drv_call(ErtsTryImmDrvCallState *sp)
     erts_port_release(prt);
 
     if (c_p) {
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+	erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
 
 	if (reds != (CONTEXT_REDS - sp->reds_left_in)) {
 	    int bump_reds = reds - (CONTEXT_REDS - sp->reds_left_in);
@@ -1171,7 +1124,7 @@ port_sched_op_reply(Eterm to, Uint32 *ref_num, Eterm msg, Port* prt)
 				  prt);
 
 	if (rp_locks)
-	    erts_smp_proc_unlock(rp, rp_locks);
+	    erts_proc_unlock(rp, rp_locks);
     }
 }
 
@@ -1189,7 +1142,7 @@ erts_schedule_proc2port_signal(Process *c_p,
     int sched_res;
     if (!refp) {
 	if (c_p)
-	    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+	    erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
     }
     else {
 	ASSERT(c_p);
@@ -1210,20 +1163,20 @@ erts_schedule_proc2port_signal(Process *c_p,
 	 *       otherwise, next receive will *not* work
 	 *       as expected!
 	 */
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	erts_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
 
 	if (ERTS_PROC_PENDING_EXIT(c_p)) {
 	    /* need to exit caller instead */
-	    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	    erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
 	    KILL_CATCHES(c_p);
 	    c_p->freason = EXC_EXIT;
 	    return ERTS_PORT_OP_CALLER_EXIT;
 	}
 
-	ERTS_SMP_MSGQ_MV_INQ2PRIVQ(c_p);
+	ERTS_MSGQ_MV_INQ2PRIVQ(c_p);
 	c_p->msg.save = c_p->msg.last;
 
-        erts_smp_proc_unlock(c_p, (ERTS_PROC_LOCKS_MSG_RECEIVE
+        erts_proc_unlock(c_p, (ERTS_PROC_LOCKS_MSG_RECEIVE
                                    | ERTS_PROC_LOCK_MAIN));
     }
 
@@ -1239,7 +1192,7 @@ erts_schedule_proc2port_signal(Process *c_p,
 					task_flags);
 
     if (c_p)
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+	erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
 
     if (sched_res != 0) {
 	if (refp) {
@@ -1250,9 +1203,9 @@ erts_schedule_proc2port_signal(Process *c_p,
 	     * containing the reference created above...
 	     */
 	    ASSERT(c_p);
-	    erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	    erts_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
 	    JOIN_MESSAGE(c_p);
-	    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	    erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
 	    *refp = NIL;
 	}
 	return ERTS_PORT_OP_DROPPED;
@@ -1285,14 +1238,14 @@ send_badsig(Port *prt) {
     ErtsProcLocks rp_locks = ERTS_PROC_LOCKS_XSIG_SEND;
     Process* rp;
     Eterm connected = ERTS_PORT_GET_CONNECTED(prt);
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     ERTS_LC_ASSERT(erts_get_scheduler_id());
 
     ASSERT(is_internal_pid(connected));
 
     rp = erts_proc_lookup_raw(connected);
     if (rp) {
-	erts_smp_proc_lock(rp, rp_locks);
+	erts_proc_lock(rp, rp_locks);
 	if (!ERTS_PROC_IS_EXITING(rp))
 	    (void) erts_send_exit_signal(NULL,
 					 prt->common.id,
@@ -1303,7 +1256,7 @@ send_badsig(Port *prt) {
 					 NULL,
 					 0);
 	if (rp_locks)
-	    erts_smp_proc_unlock(rp, rp_locks);
+	    erts_proc_unlock(rp, rp_locks);
     } /* exit sent */
 } /* send_badsig */
 
@@ -1426,7 +1379,7 @@ call_driver_outputv(int bang_op,
 	ErlDrvSizeT size = evp->size;
 	ERTS_MSACC_PUSH_AND_SET_STATE_M(ERTS_MSACC_STATE_PORT);
 
-	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt)	
+	ERTS_LC_ASSERT(erts_lc_is_port_locked(prt)
 			   || ERTS_IS_CRASH_DUMPING);
 
 
@@ -1483,7 +1436,7 @@ port_sig_outputv(Port *prt, erts_aint32_t state, int op, ErtsProc2PortSigData *s
     case ERTS_PROC2PORT_SIG_EXEC:
 	/* Execution of a scheduled outputv() call */
 
-	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+	ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
 	if (state & ERTS_PORT_SFLGS_INVALID_LOOKUP)
 	    reply = am_badarg;
@@ -1539,7 +1492,7 @@ call_driver_output(int bang_op,
     else {
 	ErtsSchedulerData *esdp = erts_get_scheduler_data();
         ERTS_MSACC_PUSH_AND_SET_STATE_M(ERTS_MSACC_STATE_PORT);
-	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt)	
+	ERTS_LC_ASSERT(erts_lc_is_port_locked(prt)
 			   || ERTS_IS_CRASH_DUMPING);
 
 #ifdef USE_VM_PROBES
@@ -1590,7 +1543,7 @@ port_sig_output(Port *prt, erts_aint32_t state, int op, ErtsProc2PortSigData *si
     case ERTS_PROC2PORT_SIG_EXEC:
 	/* Execution of a scheduled output() call */
 
-	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+	ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
 	if (state & ERTS_PORT_SFLGS_INVALID_LOOKUP)
 	    reply = am_badarg;
@@ -1805,7 +1758,7 @@ erts_port_output(Process *c_p,
      * Assumes caller have checked that port is valid...
      */
 
-    sched_flags = erts_smp_atomic32_read_nob(&prt->sched.flags);
+    sched_flags = erts_atomic32_read_nob(&prt->sched.flags);
     if (sched_flags & (busy_flgs|ERTS_PTS_FLG_EXIT))
 	return ((sched_flags & ERTS_PTS_FLG_EXIT)
 		? ERTS_PORT_OP_DROPPED
@@ -2188,7 +2141,7 @@ erts_port_output(Process *c_p,
     }
 
     if (!(flags & ERTS_PORT_SIG_FLG_FORCE)) {
-	sched_flags = erts_smp_atomic32_read_acqb(&prt->sched.flags);
+	sched_flags = erts_atomic32_read_acqb(&prt->sched.flags);
 	if (!(sched_flags & ERTS_PTS_FLG_BUSY_PORT)) {
 	    if (async_nosuspend)
 		erts_port_task_tmp_handle_detach(ns_pthp);
@@ -2413,9 +2366,9 @@ set_port_connected(int bang_op,
 	Process *rp = erts_proc_lookup_raw(connect);
 	if (!rp)
 	    return ERTS_PORT_OP_DROPPED;
-	erts_smp_proc_lock(rp, ERTS_PROC_LOCK_LINK);
+	erts_proc_lock(rp, ERTS_PROC_LOCK_LINK);
 	if (ERTS_PROC_IS_EXITING(rp)) {
-	    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	    erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 	    return ERTS_PORT_OP_DROPPED;
 	}
 
@@ -2427,7 +2380,7 @@ set_port_connected(int bang_op,
 
 	ERTS_PORT_SET_CONNECTED(prt, connect);
 
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 
         if (IS_TRACED_FL(prt, F_TRACE_PORTS))
             trace_port(prt, am_getting_linked, connect);
@@ -2620,7 +2573,7 @@ port_link_failure(Eterm port_id, Eterm linker)
 		    trace_proc(NULL, 0, rp, am_getting_unlinked, port_id);
 	    }
 	    if (rp_locks)
-		erts_smp_proc_unlock(rp, rp_locks);
+		erts_proc_unlock(rp, rp_locks);
 	}
     }
 }
@@ -2706,7 +2659,7 @@ port_monitor_failure(Eterm port_id, Eterm origin, Eterm ref_DOWN)
      * caller has never seen it yet. */
     erts_queue_monitor_message(origin_p, &p_locks, ref_DOWN,
                                am_port, port_id, am_noproc);
-    erts_smp_proc_unlock(origin_p, p_locks);
+    erts_proc_unlock(origin_p, p_locks);
 }
 
 /* Origin wants to monitor port Prt. State contains possible error, which has
@@ -2734,7 +2687,7 @@ port_monitor(Port *prt, erts_aint32_t state, Eterm origin,
         erts_add_monitor(&ERTS_P_MONITORS(prt), MON_TARGET, ref,
                          origin, name_or_nil);
 
-        erts_smp_proc_unlock(origin_p, p_locks);
+        erts_proc_unlock(origin_p, p_locks);
     } else {
 failure:
         port_monitor_failure(prt->common.id, origin, ref);
@@ -2825,7 +2778,7 @@ port_demonitor_failure(Eterm port_id, Eterm origin, Eterm ref)
         erts_destroy_monitor(mon1);
     }
 
-    erts_smp_proc_unlock(origin_p, rp_locks);
+    erts_proc_unlock(origin_p, rp_locks);
 }
 
 /* Origin wants to demonitor port Prt. State contains possible error, which has
@@ -2855,7 +2808,7 @@ port_demonitor(Port *port, erts_aint32_t state, Eterm origin, Eterm ref)
             }
         }
         if (origin_p) { /* when origin is dying, it won't be found */
-            erts_smp_proc_unlock(origin_p, p_locks);
+            erts_proc_unlock(origin_p, p_locks);
         }
     } else {
         port_demonitor_failure(port->common.id, origin, ref);
@@ -2942,10 +2895,10 @@ init_ack_send_reply(Port *port, Eterm resp)
 
     if (!is_internal_port(resp)) {
         Process *rp = erts_proc_lookup_raw(port->async_open_port->to);
-        erts_smp_proc_lock(rp, ERTS_PROC_LOCK_LINK);
+        erts_proc_lock(rp, ERTS_PROC_LOCK_LINK);
         erts_remove_link(&ERTS_P_LINKS(port), port->async_open_port->to);
         erts_remove_link(&ERTS_P_LINKS(rp), port->common.id);
-        erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+        erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
     }
     port_sched_op_reply(port->async_open_port->to,
                         port->async_open_port->ref,
@@ -3009,9 +2962,9 @@ void erts_init_io(int port_tab_size,
 {
     ErlDrvEntry** dp;
     UWord common_element_size;
-    erts_smp_rwmtx_opt_t drv_list_rwmtx_opts = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
-    drv_list_rwmtx_opts.type = ERTS_SMP_RWMTX_TYPE_EXTREMELY_FREQUENT_READ;
-    drv_list_rwmtx_opts.lived = ERTS_SMP_RWMTX_LONG_LIVED;
+    erts_rwmtx_opt_t drv_list_rwmtx_opts = ERTS_RWMTX_OPT_DEFAULT_INITER;
+    drv_list_rwmtx_opts.type = ERTS_RWMTX_TYPE_EXTREMELY_FREQUENT_READ;
+    drv_list_rwmtx_opts.lived = ERTS_RWMTX_LONG_LIVED;
 
     erts_atomic64_init_nob(&bytes_in, 0);
     erts_atomic64_init_nob(&bytes_out, 0);
@@ -3019,11 +2972,9 @@ void erts_init_io(int port_tab_size,
     common_element_size = ERTS_ALC_DATA_ALIGN_SIZE(sizeof(Port));
     common_element_size += ERTS_ALC_DATA_ALIGN_SIZE(sizeof(ErtsPortTaskBusyPortQ));
     common_element_size += 10; /* name */
-#ifdef ERTS_SMP
     common_element_size += sizeof(erts_mtx_t);
 
     init_xports_list_alloc();
-#endif
 
     pdl_init();
 
@@ -3038,12 +2989,12 @@ void erts_init_io(int port_tab_size,
     else if (port_tab_size < ERTS_MIN_PORTS)
 	port_tab_size = ERTS_MIN_PORTS;
 
-    erts_smp_rwmtx_init_opt(&erts_driver_list_lock, &drv_list_rwmtx_opts, "driver_list", NIL,
+    erts_rwmtx_init_opt(&erts_driver_list_lock, &drv_list_rwmtx_opts, "driver_list", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_IO);
     driver_list = NULL;
-    erts_smp_tsd_key_create(&driver_list_lock_status_key,
+    erts_tsd_key_create(&driver_list_lock_status_key,
 			    "erts_driver_list_lock_status_key");
-    erts_smp_tsd_key_create(&driver_list_last_error_key,
+    erts_tsd_key_create(&driver_list_last_error_key,
 			    "erts_driver_list_last_error_key");
 
     erts_ptab_init_table(&erts_port,
@@ -3058,8 +3009,8 @@ void erts_init_io(int port_tab_size,
 
     sys_init_io();
 
-    erts_smp_tsd_set(driver_list_lock_status_key, (void *) 1);
-    erts_smp_rwmtx_rwlock(&erts_driver_list_lock);
+    erts_tsd_set(driver_list_lock_status_key, (void *) 1);
+    erts_rwmtx_rwlock(&erts_driver_list_lock);
 
     init_driver(&fd_driver, &fd_driver_entry, NULL);
     init_driver(&vanilla_driver, &vanilla_driver_entry, NULL);
@@ -3071,11 +3022,11 @@ void erts_init_io(int port_tab_size,
     for (dp = driver_tab; *dp != NULL; dp++)
 	erts_add_driver_entry(*dp, NULL, 1);
 
-    erts_smp_tsd_set(driver_list_lock_status_key, NULL);
-    erts_smp_rwmtx_rwunlock(&erts_driver_list_lock);
+    erts_tsd_set(driver_list_lock_status_key, NULL);
+    erts_rwmtx_rwunlock(&erts_driver_list_lock);
 }
 
-#if defined(ERTS_ENABLE_LOCK_COUNT) && defined(ERTS_SMP)
+#if defined(ERTS_ENABLE_LOCK_COUNT)
 static void lcnt_enable_driver_lock_count(erts_driver_t *dp, int enable)
 {
     if (dp->lock) {
@@ -3164,7 +3115,8 @@ void erts_lcnt_update_port_locks(int enable) {
     }
 }
 
-#endif /* defined(ERTS_ENABLE_LOCK_COUNT) && defined(ERTS_SMP) */
+#endif /* defined(ERTS_ENABLE_LOCK_COUNT) */
+
 /*
  * Buffering of data when using line oriented I/O on ports
  */
@@ -3343,12 +3295,10 @@ deliver_result(Port *prt, Eterm sender, Eterm pid, Eterm res)
     ErtsProcLocks rp_locks = 0;
     int scheduler = erts_get_scheduler_id() != 0;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     ASSERT(!prt || prt->common.id == sender);
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
-    ASSERT(!prt || erts_lc_is_port_locked(prt));
-#endif
+    ERTS_LC_ASSERT(!prt || erts_lc_is_port_locked(prt));
 
     ASSERT(is_internal_port(sender) && is_internal_pid(pid));
 
@@ -3376,7 +3326,7 @@ deliver_result(Port *prt, Eterm sender, Eterm pid, Eterm res)
 	erts_queue_message(rp, rp_locks, mp, tuple, sender);
 
 	if (rp_locks)
-	    erts_smp_proc_unlock(rp, rp_locks);
+	    erts_proc_unlock(rp, rp_locks);
 	if (!scheduler)
 	    erts_proc_dec_refc(rp);
 
@@ -3407,8 +3357,8 @@ static void deliver_read_message(Port* prt, erts_aint32_t state, Eterm to,
     int scheduler = erts_get_scheduler_id() != 0;
     int trace_send = IS_TRACED_FL(prt, F_TRACE_SEND);
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));    
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_CHK_NO_PROC_LOCKS;
 
     need = 3 + 3 + 2*hlen;
 
@@ -3475,7 +3425,7 @@ static void deliver_read_message(Port* prt, erts_aint32_t state, Eterm to,
     ERL_MESSAGE_TOKEN(mp) = am_undefined;
     erts_queue_message(rp, rp_locks, mp, tuple, prt->common.id);
     if (rp_locks)
-	erts_smp_proc_unlock(rp, rp_locks);
+	erts_proc_unlock(rp, rp_locks);
     if (!scheduler)
 	erts_proc_dec_refc(rp);
 }
@@ -3510,7 +3460,7 @@ static void flush_linebuf_messages(Port *prt, erts_aint32_t state)
     LineBufContext lc;
     int ret;
 
-    ERTS_SMP_LC_ASSERT(!prt || erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(!prt || erts_lc_is_port_locked(prt));
 
     if (!prt)
 	return;
@@ -3554,8 +3504,8 @@ deliver_vec_message(Port* prt,			/* Port */
     erts_aint32_t state;
     int trace_send = IS_TRACED_FL(prt, F_TRACE_SEND);
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_CHK_NO_PROC_LOCKS;
 
     /*
      * Check arguments for validity.
@@ -3646,7 +3596,7 @@ deliver_vec_message(Port* prt,			/* Port */
 
     ERL_MESSAGE_TOKEN(mp) = am_undefined;
     erts_queue_message(rp, rp_locks, mp, tuple, prt->common.id);
-    erts_smp_proc_unlock(rp, rp_locks);
+    erts_proc_unlock(rp, rp_locks);
     if (!scheduler)
 	erts_proc_dec_refc(rp);
 }
@@ -3681,8 +3631,8 @@ static void flush_port(Port *p)
 {
     int fpe_was_unmasked;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(p));
+    ERTS_CHK_NO_PROC_LOCKS;
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(p));
 
     if (p->drv_ptr->flush != NULL) {
         ERTS_MSACC_PUSH_STATE_M();
@@ -3714,11 +3664,9 @@ static void flush_port(Port *p)
         if (IS_TRACED_FL(p, F_TRACE_SCHED_PORTS)) {
 	    trace_sched_ports_where(p, am_out, am_flush);
 	}
-#ifdef ERTS_SMP
 	if (p->xports)
 	    erts_port_handle_xports(p);
 	ASSERT(!p->xports);
-#endif
     }
     if ((erts_atomic32_read_nob(&p->state) & ERTS_PORT_SFLGS_DEAD) == 0
 	&& is_port_ioq_empty(p)) {
@@ -3736,8 +3684,8 @@ terminate_port(Port *prt)
     erts_aint32_t state;
     ErtsPrtSD *psd;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_CHK_NO_PROC_LOCKS;
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
     ASSERT(!ERTS_P_LINKS(prt));
     ASSERT(!ERTS_P_MONITORS(prt));
@@ -3779,11 +3727,9 @@ terminate_port(Port *prt)
 	(*drv->stop)((ErlDrvData)prt->drv_data);
 	erts_unblock_fpe(fpe_was_unmasked);
 	ERTS_MSACC_POP_STATE_M();
-#ifdef ERTS_SMP
 	if (prt->xports)
 	    erts_port_handle_xports(prt);
 	ASSERT(!prt->xports);
-#endif
     }
 
     if (is_internal_port(send_closed_port_id)
@@ -3791,9 +3737,9 @@ terminate_port(Port *prt)
         trace_port_send(prt, connected_id, am_closed, 1);
 
     if(drv->handle != NULL) {
-	erts_smp_rwmtx_rlock(&erts_driver_list_lock);
+	erts_rwmtx_rlock(&erts_driver_list_lock);
 	erts_ddll_decrement_port_count(drv->handle); 
-	erts_smp_rwmtx_runlock(&erts_driver_list_lock);
+	erts_rwmtx_runlock(&erts_driver_list_lock);
     }
     stopq(prt);        /* clear queue memory */
     if(prt->linebuf != NULL){
@@ -3803,7 +3749,7 @@ terminate_port(Port *prt)
 
     erts_cleanup_port_data(prt);
 
-    psd = (ErtsPrtSD *) erts_smp_atomic_read_nob(&prt->psd);
+    psd = (ErtsPrtSD *) erts_atomic_read_nob(&prt->psd);
     if (psd)
 	erts_free(ERTS_ALC_T_PRTSD, psd);
 
@@ -3816,7 +3762,7 @@ terminate_port(Port *prt)
      * port has been removed from the port table (in kill_port()).
      */
     if ((state & ERTS_PORT_SFLG_HALT)
-	&& (erts_smp_atomic32_dec_read_nob(&erts_halt_progress) == 0)) {
+	&& (erts_atomic32_dec_read_nob(&erts_halt_progress) == 0)) {
 	erts_port_release(prt); /* We will exit and never return */
 	erts_flush_async_exit(erts_halt_code, "");
     }
@@ -3844,7 +3790,7 @@ static void sweep_one_monitor(ErtsMonitor *mon, void *vpsc)
             goto done;
         }
         rmon = erts_remove_monitor(&ERTS_P_MONITORS(rp), mon->ref);
-        erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+        erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
         if (rmon == NULL) {
             goto done;
         }
@@ -3883,11 +3829,12 @@ static void sweep_one_link(ErtsLink *lnk, void *vpsc)
 	    ErtsDistLinkData dld;
 	    ErtsDSigData dsd;
 	    int code;
-	    code = erts_dsig_prepare(&dsd, dep, NULL, ERTS_DSP_NO_LOCK, 0);
+	    code = erts_dsig_prepare(&dsd, dep, NULL, 0, ERTS_DSP_NO_LOCK, 0, 0);
 	    switch (code) {
 	    case ERTS_DSIG_PREP_NOT_ALIVE:
 	    case ERTS_DSIG_PREP_NOT_CONNECTED:
 		break;
+	    case ERTS_DSIG_PREP_PENDING:
 	    case ERTS_DSIG_PREP_CONNECTED:
 		erts_remove_dist_link(&dld, port_id, lnk->pid, dep);
 		erts_destroy_dist_link(&dld);
@@ -3918,7 +3865,7 @@ static void sweep_one_link(ErtsLink *lnk, void *vpsc)
 						 0);
 		if (xres >= 0) {
                     if (rp_locks & ERTS_PROC_LOCKS_XSIG_SEND) {
-                        erts_smp_proc_unlock(rp, ERTS_PROC_LOCKS_XSIG_SEND);
+                        erts_proc_unlock(rp, ERTS_PROC_LOCKS_XSIG_SEND);
                         rp_locks &= ~ERTS_PROC_LOCKS_XSIG_SEND;
                     }
 		    /* We didn't exit the process and it is traced */
@@ -3928,7 +3875,7 @@ static void sweep_one_link(ErtsLink *lnk, void *vpsc)
 		erts_destroy_link(rlnk);
 	    }
 
-	    erts_smp_proc_unlock(rp, rp_locks);
+	    erts_proc_unlock(rp, rp_locks);
 	}
     }
     erts_destroy_link(lnk);
@@ -3963,7 +3910,7 @@ port_fire_one_monitor(ErtsMonitor *mon, void *ctx0)
         UnUseTmpHeapNoproc(3);
 
         rmon = erts_remove_monitor(&ERTS_P_MONITORS(origin), mon->ref);
-        erts_smp_proc_unlock(origin, origin_locks);
+        erts_proc_unlock(origin, origin_locks);
 
         if (rmon) {
             erts_destroy_monitor(rmon);
@@ -3989,8 +3936,8 @@ erts_deliver_port_exit(Port *prt, Eterm from, Eterm reason, int send_closed,
    Eterm modified_reason;
    erts_aint32_t state, set_state_flags;
 
-   ERTS_SMP_CHK_NO_PROC_LOCKS;
-   ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+   ERTS_CHK_NO_PROC_LOCKS;
+   ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
    modified_reason = (reason == am_kill) ? am_killed : reason;
 
@@ -4351,7 +4298,7 @@ port_sig_control(Port *prt,
 				      prt);
 
 	    if (rp_locks)
-		erts_smp_proc_unlock(rp, rp_locks);
+		erts_proc_unlock(rp, rp_locks);
 	    goto done;
 	}
     }
@@ -4404,7 +4351,7 @@ erts_port_control(Process* c_p,
     int copy;
     ErtsProc2PortSigData *sigdp;
 
-    sched_flags = erts_smp_atomic32_read_nob(&prt->sched.flags);
+    sched_flags = erts_atomic32_read_nob(&prt->sched.flags);
     if (sched_flags & ERTS_PTS_FLG_EXIT)
 	return ERTS_PORT_OP_BADARG;
 
@@ -4716,11 +4663,11 @@ port_sig_call(Port *prt,
 					      prt);
 
 		    if (rp_locks)
-			erts_smp_proc_unlock(rp, rp_locks);
+			erts_proc_unlock(rp, rp_locks);
 		    goto done;
 		}
 		if (rp_locks)
-		    erts_smp_proc_unlock(rp, rp_locks);
+		    erts_proc_unlock(rp, rp_locks);
 	    }
 	}
     }
@@ -4754,7 +4701,7 @@ erts_port_call(Process* c_p,
     erts_aint32_t sched_flags;
     ErtsProc2PortSigData *sigdp;
 
-    sched_flags = erts_smp_atomic32_read_nob(&prt->sched.flags);
+    sched_flags = erts_atomic32_read_nob(&prt->sched.flags);
     if (sched_flags & ERTS_PTS_FLG_EXIT) {
 	return ERTS_PORT_OP_BADARG;
     }
@@ -4972,7 +4919,7 @@ port_sig_info(Port *prt,
 				      prt);
 	}
 	if (rp_locks)
-	    erts_smp_proc_unlock(rp, rp_locks);
+	    erts_proc_unlock(rp, rp_locks);
     }
     return ERTS_PORT_REDS_INFO;
 }
@@ -5041,7 +4988,7 @@ typedef struct {
     Uint sched_id;
     Eterm pid;
     Uint32 refn[ERTS_REF_NUMBERS];
-    erts_smp_atomic32_t refc;
+    erts_atomic32_t refc;
 } ErtsIOBytesReq;
 
 static void
@@ -5091,10 +5038,10 @@ reply_io_bytes(void *vreq)
 	if (req->sched_id == sched_id)
 	    rp_locks &= ~ERTS_PROC_LOCK_MAIN;
 	if (rp_locks)
-	    erts_smp_proc_unlock(rp, rp_locks);
+	    erts_proc_unlock(rp, rp_locks);
     }
 
-    if (erts_smp_atomic32_dec_read_nob(&req->refc) == 0)
+    if (erts_atomic32_dec_read_nob(&req->refc) == 0)
 	erts_free(ERTS_ALC_T_IOB_REQ, req);
 }
 
@@ -5117,16 +5064,14 @@ erts_request_io_bytes(Process *c_p)
     req->refn[0] = refn[0];
     req->refn[1] = refn[1];
     req->refn[2] = refn[2];
-    erts_smp_atomic32_init_nob(&req->refc,
+    erts_atomic32_init_nob(&req->refc,
 			       (erts_aint32_t) erts_no_schedulers);
 
-#ifdef ERTS_SMP
     if (erts_no_schedulers > 1)
 	erts_schedule_multi_misc_aux_work(1,
 					  erts_no_schedulers,
 					  reply_io_bytes,
 					  (void *) req);
-#endif
 
     reply_io_bytes((void *) req);
 
@@ -5211,14 +5156,14 @@ set_busy_port(ErlDrvPort dprt, int on)
     DTRACE_CHARBUF(port_str, 16);
 #endif
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     prt = erts_drvport2port(dprt);
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return;
 
     if (on) {
-	flags = erts_smp_atomic32_read_bor_acqb(&prt->sched.flags,
+	flags = erts_atomic32_read_bor_acqb(&prt->sched.flags,
 						ERTS_PTS_FLG_BUSY_PORT);
 	if (flags & ERTS_PTS_FLG_BUSY_PORT)
 	    return; /* Already busy */
@@ -5234,7 +5179,7 @@ set_busy_port(ErlDrvPort dprt, int on)
         }
 #endif
     } else {
-	flags = erts_smp_atomic32_read_band_acqb(&prt->sched.flags,
+	flags = erts_atomic32_read_band_acqb(&prt->sched.flags,
 						 ~ERTS_PTS_FLG_BUSY_PORT);
 	if (!(flags & ERTS_PTS_FLG_BUSY_PORT))
 	    return; /* Already non-busy */
@@ -5328,7 +5273,7 @@ int get_port_flags(ErlDrvPort ix)
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return 0;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
     flags = 0;
     if (state & ERTS_PORT_SFLG_BINARY_IO)
@@ -5344,8 +5289,8 @@ void erts_raw_port_command(Port* p, byte* buf, Uint len)
     int fpe_was_unmasked;
     ERTS_MSACC_PUSH_STATE_M();
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(p));
+    ERTS_CHK_NO_PROC_LOCKS;
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(p));
 
     if (len > (Uint) INT_MAX)
 	erts_exit(ERTS_ABORT_EXIT,
@@ -5374,10 +5319,10 @@ int async_ready(Port *p, void* data)
 {
     int need_free = 1;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     if (p) {
-	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(p));
+	ERTS_LC_ASSERT(erts_lc_is_port_locked(p));
 	if (p->drv_ptr->ready_async != NULL) {
 	    ERTS_MSACC_PUSH_AND_SET_STATE_M(ERTS_MSACC_STATE_PORT);
 #ifdef USE_VM_PROBES
@@ -5446,24 +5391,17 @@ erts_stale_drv_select(Eterm port,
     switch (mode) {
     case ERL_DRV_READ | ERL_DRV_WRITE:
 	type = "Input/Output";
-	goto deselect;
     case ERL_DRV_WRITE:
 	type = "Output";
-	goto deselect;
     case ERL_DRV_READ:
 	type = "Input";
-    deselect:
-	if (deselect) {
-	    driver_select(drv_port, hndl,
-			  mode | ERL_DRV_USE_NO_CALLBACK,
-			  0);
-	}
-	break;
     default:
-	type = "Event";
-	if (deselect)
-	    driver_event(drv_port, hndl, NULL);
-	break;
+        type = "";
+    }
+    if (deselect) {
+        driver_select(drv_port, hndl,
+                      mode | ERL_DRV_USE_NO_CALLBACK,
+                      0);
     }
 
     dsbufp = erts_create_logger_dsbuf();
@@ -5562,8 +5500,8 @@ void driver_report_exit(ErlDrvPort ix, int status)
    if (prt == ERTS_INVALID_ERL_DRV_PORT)
        return;
 
-   ERTS_SMP_CHK_NO_PROC_LOCKS;
-   ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+   ERTS_CHK_NO_PROC_LOCKS;
+   ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
    pid = ERTS_PORT_GET_CONNECTED(prt);
    ASSERT(is_internal_pid(pid));
@@ -5586,7 +5524,7 @@ void driver_report_exit(ErlDrvPort ix, int status)
    ERL_MESSAGE_TOKEN(mp) = am_undefined;
    erts_queue_message(rp, rp_locks, mp, tuple, prt->common.id);
 
-   erts_smp_proc_unlock(rp, rp_locks);
+   erts_proc_unlock(rp, rp_locks);
    if (!scheduler)
        erts_proc_dec_refc(rp);
 }
@@ -6226,7 +6164,7 @@ driver_deliver_term(Port *prt, Eterm to, ErlDrvTermData* data, int len)
     }
     if (rp) {
 	if (rp_locks)
-	    erts_smp_proc_unlock(rp, rp_locks);
+	    erts_proc_unlock(rp, rp_locks);
 	if (!scheduler)
 	    erts_proc_dec_refc(rp);
     }
@@ -6241,9 +6179,7 @@ static ERTS_INLINE int
 deliver_term_check_port(ErlDrvTermData port_id, Eterm *connected_p,
                         Port **trace_prt)
 {
-#ifdef ERTS_SMP
     ErtsThrPrgrDelayHandle dhndl = erts_thr_progress_unmanaged_delay();
-#endif
     erts_aint32_t state;
     int res = 1;
     Port *prt = erts_port_lookup_raw((Eterm) port_id);
@@ -6261,24 +6197,20 @@ deliver_term_check_port(ErlDrvTermData port_id, Eterm *connected_p,
 	goto done;
     }
     if (connected_p) {
-#ifdef ERTS_SMP
 	if (dhndl != ERTS_THR_PRGR_DHANDLE_MANAGED)
 	    ETHR_MEMBAR(ETHR_LoadLoad);
-#endif
 	*connected_p = ERTS_PORT_GET_CONNECTED(prt);
     }
 
 done:
 
-#ifdef ERTS_SMP
     if (dhndl != ERTS_THR_PRGR_DHANDLE_MANAGED) {
-	ERTS_SMP_LC_ASSERT(!prt || !erts_lc_is_port_locked(prt));
+	ERTS_LC_ASSERT(!prt || !erts_lc_is_port_locked(prt));
 	erts_thr_progress_unmanaged_continue(dhndl);
 	ETHR_MEMBAR(ETHR_LoadLoad|ETHR_LoadStore);
     } else
-#endif
     if (res == 1) {
-	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+	ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
         *trace_prt = prt;
     }
     return res;
@@ -6306,13 +6238,13 @@ driver_output_term(ErlDrvPort drvport, ErlDrvTermData* data, int len)
     erts_aint32_t state;
     Port* prt;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     /* NOTE! It *not* safe to access 'drvport' from unmanaged threads. */
     prt = erts_drvport2port_state(drvport, &state);
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return -1; /* invalid (dead) */
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_CHK_NO_PROC_LOCKS;
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
     if (state & ERTS_PORT_SFLG_CLOSING)
 	return 0;
 
@@ -6349,16 +6281,14 @@ driver_send_term(ErlDrvPort drvport,
      * internal data representation for ErlDrvPort.
      */
     Port* prt = NULL;
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
-#ifdef ERTS_SMP
+    ERTS_CHK_NO_PROC_LOCKS;
     if (erts_thr_progress_is_managed_thread())
-#endif
     {
 	erts_aint32_t state;
 	prt = erts_drvport2port_state(drvport, &state);
 	if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	    return -1; /* invalid (dead) */
-	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+	ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 	if (state & ERTS_PORT_SFLG_CLOSING)
 	    return 0;
     }
@@ -6378,11 +6308,11 @@ int driver_output_binary(ErlDrvPort ix, char* hbuf, ErlDrvSizeT hlen,
     Port* prt = erts_drvport2port_state(ix, &state);
     ErtsSchedulerData *esdp = erts_get_scheduler_data();
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return -1;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
     if (state & ERTS_PORT_SFLG_CLOSING)
 	return 0;
 
@@ -6392,6 +6322,7 @@ int driver_output_binary(ErlDrvPort ix, char* hbuf, ErlDrvSizeT hlen,
     else
 	erts_atomic64_add_nob(&bytes_in, (erts_aint64_t) (hlen + len));
     if (state & ERTS_PORT_SFLG_DISTRIBUTION) {
+        erts_atomic64_inc_nob(&prt->dist_entry->in);
 	return erts_net_message(prt,
 				prt->dist_entry,
 				(byte*) hbuf, hlen,
@@ -6417,12 +6348,12 @@ int driver_output2(ErlDrvPort ix, char* hbuf, ErlDrvSizeT hlen,
     Port* prt = erts_drvport2port_state(ix, &state);
     ErtsSchedulerData *esdp = erts_get_scheduler_data();
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return -1;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
     if (state & ERTS_PORT_SFLG_CLOSING)
 	return 0;
     
@@ -6432,6 +6363,7 @@ int driver_output2(ErlDrvPort ix, char* hbuf, ErlDrvSizeT hlen,
     else
 	erts_atomic64_add_nob(&bytes_in, (erts_aint64_t) (hlen + len));
     if (state & ERTS_PORT_SFLG_DISTRIBUTION) {
+        erts_atomic64_inc_nob(&prt->dist_entry->in);
 	if (len == 0)
 	    return erts_net_message(prt,
 				    prt->dist_entry,
@@ -6456,7 +6388,7 @@ int driver_output2(ErlDrvPort ix, char* hbuf, ErlDrvSizeT hlen,
 
 int driver_output(ErlDrvPort ix, char* buf, ErlDrvSizeT len)
 {
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     return driver_output2(ix, NULL, 0, buf, len);
 }
 
@@ -6472,7 +6404,7 @@ int driver_outputv(ErlDrvPort ix, char* hbuf, ErlDrvSizeT hlen,
     erts_aint32_t state;
     ErtsSchedulerData *esdp = erts_get_scheduler_data();
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     ASSERT(vec->size >= skip);
     if (vec->size <= skip)
@@ -6483,7 +6415,7 @@ int driver_outputv(ErlDrvPort ix, char* hbuf, ErlDrvSizeT hlen,
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return -1;
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
     if (state & ERTS_PORT_SFLG_CLOSING)
 	return 0;
@@ -6697,7 +6629,6 @@ static ERTS_INLINE void pdl_destroy(ErlDrvPDL pdl)
     erts_free(ERTS_ALC_T_PORT_DATA_LOCK, pdl);
 }
 
-#ifdef ERTS_SMP
 
 static void driver_monitor_lock_pdl(Port *p) {
     if (p->port_data_lock) {
@@ -6706,7 +6637,7 @@ static void driver_monitor_lock_pdl(Port *p) {
     /* Now we either have the port lock or the port_data_lock */
     ERTS_LC_ASSERT(!p->port_data_lock
 		   || erts_lc_mtx_is_locked(&(p->port_data_lock->mtx)));
-    ERTS_SMP_LC_ASSERT(p->port_data_lock
+    ERTS_LC_ASSERT(p->port_data_lock
 		       || erts_lc_is_port_locked(p));
 }
 
@@ -6714,14 +6645,13 @@ static void driver_monitor_unlock_pdl(Port *p) {
     /* We should either have the port lock or the port_data_lock */
     ERTS_LC_ASSERT(!p->port_data_lock
 		   || erts_lc_mtx_is_locked(&(p->port_data_lock->mtx)));
-    ERTS_SMP_LC_ASSERT(p->port_data_lock
+    ERTS_LC_ASSERT(p->port_data_lock
 		       || erts_lc_is_port_locked(p));
     if (p->port_data_lock) {
 	driver_pdl_unlock(p->port_data_lock);
     }
 }
 
-#endif
 
 /*
  * exported driver_pdl_* functions ...
@@ -6924,7 +6854,7 @@ int driver_set_timer(ErlDrvPort ix, unsigned long t)
 {
     Port* prt = erts_drvport2port(ix);
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return -1;
@@ -6941,7 +6871,7 @@ int driver_cancel_timer(ErlDrvPort ix)
     Port* prt = erts_drvport2port(ix);
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return -1;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
     erts_cancel_port_timer(prt);
     return 0;
 }
@@ -6952,11 +6882,11 @@ driver_read_timer(ErlDrvPort ix, unsigned long* t)
     Port* prt = erts_drvport2port(ix);
     Sint64 left;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return -1;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
     left = erts_read_port_timer(prt);
     if (left < 0)
@@ -6971,7 +6901,7 @@ int
 driver_get_now(ErlDrvNowData *now_data)
 {
     Uint mega,secs,micro;
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     if (now_data == NULL) {
 	return -1;
@@ -7045,7 +6975,7 @@ static int do_driver_monitor_process(Port *prt,
     erts_add_monitor(&ERTS_P_MONITORS(prt), MON_ORIGIN, ref, rp->common.id, NIL);
     erts_add_monitor(&ERTS_P_MONITORS(rp), MON_TARGET, ref, prt->common.id, NIL);
 
-    erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+    erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
     erts_ref_to_driver_monitor(ref,monitor);
     return 0;
 }
@@ -7059,7 +6989,7 @@ int driver_monitor_process(ErlDrvPort drvport,
 {
     Port *prt;
     int ret;
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     ErtsSchedulerData *sched = erts_get_scheduler_data();
 #endif
 
@@ -7069,7 +6999,7 @@ int driver_monitor_process(ErlDrvPort drvport,
 
     /* Now (in SMP) we should have either the port lock (if we have a scheduler) or the port data lock
        (if we're a driver thread) */
-    ERTS_SMP_LC_ASSERT((sched != NULL || prt->port_data_lock));
+    ERTS_LC_ASSERT((sched != NULL || prt->port_data_lock));
     ret = do_driver_monitor_process(prt,process,monitor);
     DRV_MONITOR_UNLOCK_PDL(prt);
     return ret;
@@ -7104,7 +7034,7 @@ static int do_driver_demonitor_process(Port *prt, const ErlDrvMonitor *monitor)
     if (rp) {
 	ErtsMonitor *rmon;
 	rmon = erts_remove_monitor(&ERTS_P_MONITORS(rp), ref);
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 	if (rmon != NULL) {
 	    erts_destroy_monitor(rmon);
 	}
@@ -7117,7 +7047,7 @@ int driver_demonitor_process(ErlDrvPort drvport,
 {
     Port *prt;
     int ret;
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     ErtsSchedulerData *sched = erts_get_scheduler_data();
 #endif
 
@@ -7127,7 +7057,7 @@ int driver_demonitor_process(ErlDrvPort drvport,
 
     /* Now we should have either the port lock (if we have a scheduler) or the port data lock
        (if we're a driver thread) */
-    ERTS_SMP_LC_ASSERT((sched != NULL || prt->port_data_lock));
+    ERTS_LC_ASSERT((sched != NULL || prt->port_data_lock));
     ret = do_driver_demonitor_process(prt,monitor);
     DRV_MONITOR_UNLOCK_PDL(prt);
     return ret;
@@ -7158,7 +7088,7 @@ ErlDrvTermData driver_get_monitored_process(ErlDrvPort drvport,
 {
     Port *prt;
     ErlDrvTermData ret;
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     ErtsSchedulerData *sched = erts_get_scheduler_data();
 #endif
 
@@ -7168,7 +7098,7 @@ ErlDrvTermData driver_get_monitored_process(ErlDrvPort drvport,
 
     /* Now we should have either the port lock (if we have a scheduler) or the port data lock
        (if we're a driver thread) */
-    ERTS_SMP_LC_ASSERT((sched != NULL || prt->port_data_lock));
+    ERTS_LC_ASSERT((sched != NULL || prt->port_data_lock));
     ret = do_driver_get_monitored_process(prt,monitor);
     DRV_MONITOR_UNLOCK_PDL(prt);
     return ret;
@@ -7189,7 +7119,7 @@ void erts_fire_port_monitor(Port *prt, Eterm ref)
     int fpe_was_unmasked;
     ERTS_MSACC_PUSH_STATE_M();
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
     ASSERT(prt->drv_ptr != NULL);    
     DRV_MONITOR_LOCK_PDL(prt);
     if (erts_lookup_monitor(ERTS_P_MONITORS(prt), ref) == NULL) {
@@ -7236,11 +7166,11 @@ driver_failure_term(ErlDrvPort ix, Eterm term, int eof)
     erts_aint32_t state;
     Port* prt = erts_drvport2port_state(ix, &state);
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return -1;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
     if (prt->async_open_port)
         init_ack_send_reply(prt, prt->common.id);
@@ -7275,7 +7205,7 @@ int driver_exit(ErlDrvPort ix, int err)
     ErtsLink *lnk, *rlnk = NULL;
     Eterm connected;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
   
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
         return -1;
@@ -7288,10 +7218,8 @@ int driver_exit(ErlDrvPort ix, int err)
 
     lnk = erts_remove_link(&ERTS_P_LINKS(prt), connected);
 
-#ifdef ERTS_SMP
     if (rp)
-	erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
-#endif
+	erts_proc_unlock(rp, ERTS_PROC_LOCK_LINK);
 
     if (rlnk != NULL) {
 	erts_destroy_link(rlnk);
@@ -7345,7 +7273,7 @@ ErlDrvTermData driver_mk_atom(char* string)
 			     sys_strlen(string),
 			     ERTS_ATOM_ENC_LATIN1,
 			     1);
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     return (ErlDrvTermData) am;
 }
 
@@ -7354,27 +7282,27 @@ ErlDrvTermData driver_mk_port(ErlDrvPort ix)
     Port* prt = erts_drvport2port(ix);
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return (ErlDrvTermData) NIL;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
     return (ErlDrvTermData) prt->common.id;
 }
 
 ErlDrvTermData driver_connected(ErlDrvPort ix)
 {
     Port* prt = erts_drvport2port(ix);
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return NIL;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
     return ERTS_PORT_GET_CONNECTED(prt);
 }
 
 ErlDrvTermData driver_caller(ErlDrvPort ix)
 {
     Port* prt = erts_drvport2port(ix);
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return NIL;
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
     return prt->caller;
 }
 
@@ -7383,20 +7311,20 @@ int driver_lock_driver(ErlDrvPort ix)
     Port* prt = erts_drvport2port(ix);
     DE_Handle* dh;
 
-    ERTS_SMP_CHK_NO_PROC_LOCKS;
+    ERTS_CHK_NO_PROC_LOCKS;
 
     if (prt == ERTS_INVALID_ERL_DRV_PORT)
 	return -1;
 
-    erts_smp_rwmtx_rwlock(&erts_driver_list_lock);
+    erts_rwmtx_rwlock(&erts_driver_list_lock);
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
     if ((dh = (DE_Handle*)prt->drv_ptr->handle ) == NULL) {
-	erts_smp_rwmtx_rwunlock(&erts_driver_list_lock);
+	erts_rwmtx_rwunlock(&erts_driver_list_lock);
 	return -1;
     }
     erts_ddll_lock_driver(dh, prt->drv_ptr->name);
-    erts_smp_rwmtx_rwunlock(&erts_driver_list_lock);
+    erts_rwmtx_rwunlock(&erts_driver_list_lock);
     return 0;
 }
 
@@ -7404,9 +7332,9 @@ int driver_lock_driver(ErlDrvPort ix)
 static int maybe_lock_driver_list(void) 
 {
     void *rec_lock;
-    rec_lock = erts_smp_tsd_get(driver_list_lock_status_key);
+    rec_lock = erts_tsd_get(driver_list_lock_status_key);
     if (rec_lock == 0) {
-	erts_smp_rwmtx_rwlock(&erts_driver_list_lock);
+	erts_rwmtx_rwlock(&erts_driver_list_lock);
 	return 1;
     }
     return 0;
@@ -7414,7 +7342,7 @@ static int maybe_lock_driver_list(void)
 static void maybe_unlock_driver_list(int doit)
 {
     if (doit) {
-	erts_smp_rwmtx_rwunlock(&erts_driver_list_lock);
+	erts_rwmtx_rwunlock(&erts_driver_list_lock);
     }
 }
 /* 
@@ -7437,7 +7365,7 @@ void *driver_dl_open(char * path)
 {
     void *ptr;
     int res;
-    int *last_error_p = erts_smp_tsd_get(driver_list_last_error_key);
+    int *last_error_p = erts_tsd_get(driver_list_last_error_key);
     int locked = maybe_lock_driver_list();
     if ((res = erts_sys_ddll_open(path, &ptr, NULL)) == 0) {
 	maybe_unlock_driver_list(locked);
@@ -7445,7 +7373,7 @@ void *driver_dl_open(char * path)
     } else {
 	if (!last_error_p) {
 	    last_error_p = erts_alloc(ERTS_ALC_T_DDLL_ERRCODES, sizeof(int));
-	    erts_smp_tsd_set(driver_list_last_error_key,last_error_p);
+	    erts_tsd_set(driver_list_last_error_key,last_error_p);
 	}
 	*last_error_p = res;
 	maybe_unlock_driver_list(locked);
@@ -7457,7 +7385,7 @@ void *driver_dl_sym(void * handle, char *func_name)
 {
     void *ptr;
     int res;
-    int *last_error_p = erts_smp_tsd_get(driver_list_lock_status_key);
+    int *last_error_p = erts_tsd_get(driver_list_lock_status_key);
     int locked = maybe_lock_driver_list();
     if ((res = erts_sys_ddll_sym(handle, func_name, &ptr)) == 0) {
 	maybe_unlock_driver_list(locked);
@@ -7465,7 +7393,7 @@ void *driver_dl_sym(void * handle, char *func_name)
     } else {
 	if (!last_error_p) {
 	    last_error_p = erts_alloc(ERTS_ALC_T_DDLL_ERRCODES, sizeof(int));
-	    erts_smp_tsd_set(driver_list_lock_status_key,last_error_p);
+	    erts_tsd_set(driver_list_lock_status_key,last_error_p);
 	}
 	*last_error_p = res;
 	maybe_unlock_driver_list(locked);
@@ -7485,7 +7413,7 @@ int driver_dl_close(void *handle)
 char *driver_dl_error(void) 
 {
     char *res;
-    int *last_error_p = erts_smp_tsd_get(driver_list_lock_status_key);
+    int *last_error_p = erts_tsd_get(driver_list_lock_status_key);
     int locked = maybe_lock_driver_list();
     res = erts_ddll_error((last_error_p != NULL) ? (*last_error_p) : ERL_DE_ERROR_UNSPECIFIED); 
     maybe_unlock_driver_list(locked);
@@ -7523,20 +7451,8 @@ driver_system_info(ErlDrvSysInfo *sip, size_t si_size)
 	sip->driver_minor_version = ERL_DRV_EXTENDED_MINOR_VERSION;
 	sip->erts_version = ERLANG_VERSION;
 	sip->otp_release = ERLANG_OTP_RELEASE;
-	sip->thread_support = 
-#ifdef USE_THREADS
-	    1
-#else
-	    0
-#endif
-	    ;
-	sip->smp_support = 
-#ifdef ERTS_SMP
-	    1
-#else
-	    0
-#endif
-	    ;
+	sip->thread_support = 1;
+	sip->smp_support = 1;
 
     }
 
@@ -7562,11 +7478,7 @@ driver_system_info(ErlDrvSysInfo *sip, size_t si_size)
      */
     if (si_size >= ERL_DRV_SYS_INFO_SIZE(dirty_scheduler_support)) {
 	sip->dirty_scheduler_support =
-#ifdef ERTS_DIRTY_SCHEDULERS
 	    1
-#else
-	    0
-#endif
 	    ;
     }
 
@@ -7593,14 +7505,6 @@ no_output_callback(ErlDrvData drv_data, char *buf, ErlDrvSizeT len)
 }
 
 static void
-no_event_callback(ErlDrvData drv_data, ErlDrvEvent event, ErlDrvEventData event_data)
-{
-    Port *prt = get_current_port();
-    report_missing_drv_callback(prt, "Event", "event()");
-    driver_event(ERTS_Port2ErlDrvPort(prt), event, NULL);
-}
-
-static void
 no_ready_input_callback(ErlDrvData drv_data, ErlDrvEvent event)
 {
     Port *prt = get_current_port();
@@ -7646,7 +7550,6 @@ init_driver(erts_driver_t *drv, ErlDrvEntry *de, DE_Handle *handle)
     drv->version.minor = de->minor_version;
     drv->flags = de->driver_flags;
     drv->handle = handle;
-#ifdef ERTS_SMP
     if (drv->flags & ERL_DRV_FLAG_USE_PORT_LOCKING) {
         drv->lock = NULL;
     } else {
@@ -7658,7 +7561,6 @@ init_driver(erts_driver_t *drv, ErlDrvEntry *de, DE_Handle *handle)
 
         erts_mtx_init(drv->lock, "driver_lock", driver_id, ERTS_LOCK_FLAGS_CATEGORY_IO);
     }
-#endif
     drv->entry = de;
 
     drv->start = de->start;
@@ -7669,7 +7571,6 @@ init_driver(erts_driver_t *drv, ErlDrvEntry *de, DE_Handle *handle)
     drv->outputv = de->outputv;
     drv->control = de->control;
     drv->call = de->call;
-    drv->event = de->event ? de->event : no_event_callback;
     drv->ready_input = de->ready_input ? de->ready_input : no_ready_input_callback;
     drv->ready_output = de->ready_output ? de->ready_output : no_ready_output_callback;
     drv->timeout = de->timeout ? de->timeout : no_timeout_callback;
@@ -7701,12 +7602,10 @@ init_driver(erts_driver_t *drv, ErlDrvEntry *de, DE_Handle *handle)
 void
 erts_destroy_driver(erts_driver_t *drv)
 {
-#ifdef ERTS_SMP
     if (drv->lock) {
-	erts_smp_mtx_destroy(drv->lock);
+	erts_mtx_destroy(drv->lock);
 	erts_free(ERTS_ALC_T_DRIVER_LOCK, drv->lock);
     }
-#endif    
     erts_free(ERTS_ALC_T_DRIVER, drv);
 }
 
@@ -7717,7 +7616,7 @@ erts_destroy_driver(erts_driver_t *drv)
 
 void add_driver_entry(ErlDrvEntry *drv){
     void *rec_lock;
-    rec_lock = erts_smp_tsd_get(driver_list_lock_status_key);
+    rec_lock = erts_tsd_get(driver_list_lock_status_key);
     /* 
      * Ignore result of erts_add_driver_entry, the init is not
      * allowed to fail when drivers are added by drivers.
@@ -7731,7 +7630,7 @@ int erts_add_driver_entry(ErlDrvEntry *de, DE_Handle *handle, int driver_list_lo
     int res;
 
     if (!driver_list_locked) {
-	erts_smp_rwmtx_rwlock(&erts_driver_list_lock);
+	erts_rwmtx_rwlock(&erts_driver_list_lock);
     }
 
     dp->next = driver_list;
@@ -7742,7 +7641,7 @@ int erts_add_driver_entry(ErlDrvEntry *de, DE_Handle *handle, int driver_list_lo
     driver_list = dp;
 
     if (!driver_list_locked) {
-	erts_smp_tsd_set(driver_list_lock_status_key, (void *) 1);
+	erts_tsd_set(driver_list_lock_status_key, (void *) 1);
     }
 
     res = init_driver(dp, de, handle);
@@ -7759,8 +7658,8 @@ int erts_add_driver_entry(ErlDrvEntry *de, DE_Handle *handle, int driver_list_lo
     }
 	
     if (!driver_list_locked) {
-	erts_smp_tsd_set(driver_list_lock_status_key, NULL);
-	erts_smp_rwmtx_rwunlock(&erts_driver_list_lock);
+	erts_tsd_set(driver_list_lock_status_key, NULL);
+	erts_rwmtx_rwunlock(&erts_driver_list_lock);
     }
     return res;
 }
@@ -7771,9 +7670,9 @@ int remove_driver_entry(ErlDrvEntry *drv)
     erts_driver_t *dp;
     void *rec_lock;
     
-    rec_lock = erts_smp_tsd_get(driver_list_lock_status_key);
+    rec_lock = erts_tsd_get(driver_list_lock_status_key);
     if (rec_lock == NULL) {
-	erts_smp_rwmtx_rwlock(&erts_driver_list_lock);
+	erts_rwmtx_rwlock(&erts_driver_list_lock);
     }
     dp = driver_list;
     while (dp && dp->entry != drv)
@@ -7781,7 +7680,7 @@ int remove_driver_entry(ErlDrvEntry *drv)
     if (dp) {
 	if (dp->handle) {
 	    if (rec_lock == NULL) {
-		erts_smp_rwmtx_rwunlock(&erts_driver_list_lock);
+		erts_rwmtx_rwunlock(&erts_driver_list_lock);
 	    }
 	    return -1;
 	}
@@ -7795,12 +7694,12 @@ int remove_driver_entry(ErlDrvEntry *drv)
 	}
 	erts_destroy_driver(dp);
 	if (rec_lock == NULL) {
-	    erts_smp_rwmtx_rwunlock(&erts_driver_list_lock);
+	    erts_rwmtx_rwunlock(&erts_driver_list_lock);
 	}
 	return 1;
     }
     if (rec_lock == NULL) {
-	erts_smp_rwmtx_rwunlock(&erts_driver_list_lock);
+	erts_rwmtx_rwunlock(&erts_driver_list_lock);
     }
     return 0;
 }
diff --git a/erts/emulator/beam/macros.tab b/erts/emulator/beam/macros.tab
new file mode 100644
index 0000000000..494fe8961e
--- /dev/null
+++ b/erts/emulator/beam/macros.tab
@@ -0,0 +1,173 @@
+// -*- c -*-
+//
+// %CopyrightBegin%
+//
+// Copyright Ericsson AB 2017. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// %CopyrightEnd%
+//
+
+//
+// Define a regular expression that will match instructions that
+// perform GC.  That will allow beam_makeops to check for instructions
+// that don't use $REFRESH_GEN_DEST() when they should.
+//
+
+GC_REGEXP=erts_garbage_collect|erts_gc|GcBifFunction;
+
+// $Offset is relative to the start of the instruction (not to the
+// location of the failure label reference). Since combined
+// instructions may increment the instruction pointer (e.g. in
+// 'increment') for some of the instructions in the group, we actually
+// use a virtual start position common to all instructions in the
+// group. To calculate the correct virtual position, we will need to
+// add $IP_ADJUSTMENT to the offset. ($IP_ADJUSTMENT will usually be
+// zero, except in a few bit syntax instructions.)
+
+SET_I_REL(Offset) {
+    ASSERT(VALID_INSTR(*(I + ($Offset) + $IP_ADJUSTMENT)));
+    I += $Offset + $IP_ADJUSTMENT;
+}
+
+SET_CP_I_ABS(Target) {
+    c_p->i = $Target;
+    ASSERT(VALID_INSTR(*c_p->i));
+}
+
+SET_REL_I(Dst, Offset) {
+    $Dst = I + ($Offset);
+    ASSERT(VALID_INSTR(*$Dst));
+}
+
+FAIL(Fail) {
+    //| -no_prefetch
+    $SET_I_REL($Fail);
+    Goto(*I);
+}
+
+JUMP(Fail) {
+    //| -no_next
+    $SET_I_REL($Fail);
+    Goto(*I);
+}
+
+GC_TEST(Ns, Nh, Live) {
+    Uint need = $Nh + $Ns;
+    if (ERTS_UNLIKELY(E - HTOP < need)) {
+       SWAPOUT;
+       PROCESS_MAIN_CHK_LOCKS(c_p);
+       FCALLS -= erts_garbage_collect_nobump(c_p, need, reg, $Live, FCALLS);
+       ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+       PROCESS_MAIN_CHK_LOCKS(c_p);
+       SWAPIN;
+    }
+    HEAP_SPACE_VERIFIED($Nh);
+}
+
+GC_TEST_PRESERVE(NeedHeap, Live, PreserveTerm) {
+    Uint need = $NeedHeap;
+    if (ERTS_UNLIKELY(E - HTOP < need)) {
+       SWAPOUT;
+       reg[$Live] = $PreserveTerm;
+       PROCESS_MAIN_CHK_LOCKS(c_p);
+       FCALLS -= erts_garbage_collect_nobump(c_p, need, reg, $Live+1, FCALLS);
+       ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+       PROCESS_MAIN_CHK_LOCKS(c_p);
+       $PreserveTerm = reg[$Live];
+       SWAPIN;
+    }
+    HEAP_SPACE_VERIFIED($NeedHeap);
+}
+
+
+// Make sure that there are NeedStack + NeedHeap + 1 words available
+// on the combined heap/stack segment, then allocates NeedHeap + 1
+// words on the stack and saves CP.
+AH(NeedStack, NeedHeap, Live) {
+    unsigned needed = $NeedStack + 1;
+    $GC_TEST(needed, $NeedHeap, $Live);
+    E -= needed;
+    *E = make_cp(c_p->cp);
+    c_p->cp = 0;
+}
+
+NEXT0() {
+    //| -no_next
+    SET_I((BeamInstr *) $NEXT_INSTRUCTION);
+    Goto(*I);
+}
+
+NEXT(Addr) {
+    //| -no_next
+    SET_I((BeamInstr *) $Addr);
+    Goto(*I);
+}
+
+FAIL_BODY() {
+    //| -no_prefetch
+    goto find_func_info;
+}
+
+FAIL_HEAD_OR_BODY(Fail) {
+    //| -no_prefetch
+
+    /*
+     * In a correctly working program, we expect failures in
+     * guards to be more likely than failures in bodies.
+     */
+
+    if (ERTS_LIKELY($Fail)) {
+        $FAIL($Fail);
+    }
+    goto find_func_info;
+}
+
+BADARG(Fail) {
+    c_p->freason = BADARG;
+    $FAIL_HEAD_OR_BODY($Fail);
+}
+
+BADARITH0() {
+    c_p->freason = BADARITH;
+    goto find_func_info;
+}
+
+SYSTEM_LIMIT(Fail) {
+    c_p->freason = SYSTEM_LIMIT;
+    $FAIL_HEAD_OR_BODY($Fail);
+}
+
+BIF_ERROR_ARITY_1(Fail, BIF, Op1) {
+    //| -no_prefetch
+    if (ERTS_LIKELY($Fail)) {
+        $FAIL($Fail);
+    }
+    reg[0] = $Op1;
+    SWAPOUT;
+    I = handle_error(c_p, I, reg, &bif_export[$BIF]->info.mfa);
+    goto post_error_handling;
+}
+
+BIF_ERROR_ARITY_2(Fail, BIF, Op1, Op2) {
+    //| -no_prefetch
+    if (ERTS_LIKELY($Fail)) {
+        $FAIL($Fail);
+    }
+    reg[0] = $Op1;
+    reg[1] = $Op2;
+    SWAPOUT;
+    I = handle_error(c_p, I, reg, &bif_export[$BIF]->info.mfa);
+    goto post_error_handling;
+}
diff --git a/erts/emulator/beam/map_instrs.tab b/erts/emulator/beam/map_instrs.tab
new file mode 100644
index 0000000000..c594a87298
--- /dev/null
+++ b/erts/emulator/beam/map_instrs.tab
@@ -0,0 +1,159 @@
+// -*- c -*-
+//
+// %CopyrightBegin%
+//
+// Copyright Ericsson AB 2017. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// %CopyrightEnd%
+//
+
+ensure_map(Map) {
+    if (is_not_map($Map)) {
+        c_p->freason = BADMAP;
+        c_p->fvalue = $Map;
+        $FAIL_BODY();
+    }
+}
+
+new_map(Dst, Live, N) {
+    Eterm res;
+
+    HEAVY_SWAPOUT;
+    res = erts_gc_new_map(c_p, reg, $Live, $N, $NEXT_INSTRUCTION);
+    HEAVY_SWAPIN;
+    $REFRESH_GEN_DEST();
+    $Dst = res;
+    $NEXT($NEXT_INSTRUCTION+$N);
+}
+
+i_new_small_map_lit(Dst, Live, Keys) {
+    Eterm res;
+    Uint n;
+    Eterm keys = $Keys;
+
+    HEAVY_SWAPOUT;
+    res = erts_gc_new_small_map_lit(c_p, reg, keys, $Live, $NEXT_INSTRUCTION);
+    HEAVY_SWAPIN;
+    $REFRESH_GEN_DEST();
+    $Dst = res;
+    n = arityval(*tuple_val(keys));
+    $NEXT($NEXT_INSTRUCTION+n);
+}
+
+i_get_map_element(Fail, Src, Key, Dst) {
+    Eterm res = get_map_element($Src, $Key);
+    if (is_non_value(res)) {
+        $FAIL($Fail);
+    }
+    $Dst = res;
+}
+
+i_get_map_element_hash(Fail, Src, Key, Hx, Dst) {
+     Eterm res = get_map_element_hash($Src, $Key, $Hx);
+     if (is_non_value(res)) {
+        $FAIL($Fail);
+     }
+     $Dst = res;
+}
+
+i_get_map_elements(Fail, Src, N) {
+    Eterm map;
+    BeamInstr *fs;
+    Uint sz, n;
+
+    map = $Src;
+
+    /* This instruction assumes Arg1 is a map,
+     * i.e. that it follows a test is_map if needed.
+     */
+
+    n  = (Uint)$N / 3;
+    fs = $NEXT_INSTRUCTION;
+
+    if (is_flatmap(map)) {
+	flatmap_t *mp;
+	Eterm *ks;
+	Eterm *vs;
+
+	mp = (flatmap_t *)flatmap_val(map);
+	sz = flatmap_get_size(mp);
+
+	if (sz == 0) {
+            $FAIL($Fail);
+	}
+
+	ks = flatmap_get_keys(mp);
+	vs = flatmap_get_values(mp);
+
+	while(sz) {
+	    if (EQ((Eterm) fs[0], *ks)) {
+		PUT_TERM_REG(*vs, fs[1]);
+		n--;
+		fs += 3;
+		/* no more values to fetch, we are done */
+		if (n == 0) {
+                    $NEXT(fs);
+		}
+	    }
+	    ks++, sz--, vs++;
+	}
+        $FAIL($Fail);
+    } else {
+	const Eterm *v;
+	Uint32 hx;
+	ASSERT(is_hashmap(map));
+	while(n--) {
+	    hx = fs[2];
+	    ASSERT(hx == hashmap_make_hash((Eterm)fs[0]));
+	    if ((v = erts_hashmap_get(hx, (Eterm)fs[0], map)) == NULL) {
+		$FAIL($Fail);
+	    }
+	    PUT_TERM_REG(*v, fs[1]);
+	    fs += 3;
+	}
+        $NEXT(fs);
+    }
+}
+
+update_map_assoc(Src, Dst, Live, N) {
+    Eterm res;
+    Uint live = $Live;
+
+    reg[live] = $Src;
+    HEAVY_SWAPOUT;
+    res = erts_gc_update_map_assoc(c_p, reg, live, $N, $NEXT_INSTRUCTION);
+    HEAVY_SWAPIN;
+    ASSERT(is_value(res));
+    $REFRESH_GEN_DEST();
+    $Dst = res;
+    $NEXT($NEXT_INSTRUCTION+$N);
+}
+
+update_map_exact(Fail, Src, Dst, Live, N) {
+    Eterm res;
+    Uint live = $Live;
+
+    reg[live] = $Src;
+    HEAVY_SWAPOUT;
+    res = erts_gc_update_map_exact(c_p, reg, live, $N, $NEXT_INSTRUCTION);
+    HEAVY_SWAPIN;
+    if (is_value(res)) {
+        $REFRESH_GEN_DEST();
+        $Dst = res;
+        $NEXT($NEXT_INSTRUCTION+$N);
+    } else {
+        $FAIL_HEAD_OR_BODY($Fail);
+    }
+}
diff --git a/erts/emulator/beam/module.c b/erts/emulator/beam/module.c
index a386407ec2..1712dc803c 100644
--- a/erts/emulator/beam/module.c
+++ b/erts/emulator/beam/module.c
@@ -39,9 +39,9 @@
 
 static IndexTable module_tables[ERTS_NUM_CODE_IX];
 
-erts_smp_rwmtx_t the_old_code_rwlocks[ERTS_NUM_CODE_IX];
+erts_rwmtx_t the_old_code_rwlocks[ERTS_NUM_CODE_IX];
 
-static erts_smp_atomic_t tot_module_bytes;
+static erts_atomic_t tot_module_bytes;
 
 /* SMP note: Active module table lookup and current module instance can be
  *           read without any locks. Old module instances are protected by
@@ -49,8 +49,6 @@ static erts_smp_atomic_t tot_module_bytes;
  *           Staging table is protected by the "code_ix lock". 
  */
 
-#include "erl_smp.h"
-
 void module_info(fmtfn_t to, void *to_arg)
 {
     index_info(to, to_arg, &module_tables[erts_active_code_ix()]);
@@ -84,7 +82,7 @@ void erts_module_instance_init(struct erl_module_instance* modi)
 static Module* module_alloc(Module* tmpl)
 {
     Module* obj = (Module*) erts_alloc(ERTS_ALC_T_MODULE, sizeof(Module));
-    erts_smp_atomic_add_nob(&tot_module_bytes, sizeof(Module));
+    erts_atomic_add_nob(&tot_module_bytes, sizeof(Module));
 
     obj->module = tmpl->module;
     obj->slot.index = -1;
@@ -98,7 +96,7 @@ static Module* module_alloc(Module* tmpl)
 static void module_free(Module* mod)
 {
     erts_free(ERTS_ALC_T_MODULE, mod);
-    erts_smp_atomic_add_nob(&tot_module_bytes, -sizeof(Module));
+    erts_atomic_add_nob(&tot_module_bytes, -sizeof(Module));
 }
 
 void init_module_table(void)
@@ -120,10 +118,10 @@ void init_module_table(void)
     }
 
     for (i=0; i<ERTS_NUM_CODE_IX; i++) {
-        erts_smp_rwmtx_init(&the_old_code_rwlocks[i], "old_code", make_small(i),
+        erts_rwmtx_init(&the_old_code_rwlocks[i], "old_code", make_small(i),
             ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
     }
-    erts_smp_atomic_init_nob(&tot_module_bytes, 0);
+    erts_atomic_init_nob(&tot_module_bytes, 0);
 }
 
 
@@ -159,14 +157,14 @@ static Module* put_module(Eterm mod, IndexTable* mod_tab)
     oldsz = index_table_sz(mod_tab);
     res = (Module*) index_put_entry(mod_tab, (void*) &e);
     newsz = index_table_sz(mod_tab);
-    erts_smp_atomic_add_nob(&tot_module_bytes, (newsz - oldsz));
+    erts_atomic_add_nob(&tot_module_bytes, (newsz - oldsz));
     return res;
 }
 
 Module*
 erts_put_module(Eterm mod)
 {
-    ERTS_SMP_LC_ASSERT(erts_initialized == 0
+    ERTS_LC_ASSERT(erts_initialized == 0
 		       || erts_has_code_write_permission());
 
     return put_module(mod, &module_tables[erts_staging_code_ix()]);
@@ -184,7 +182,7 @@ int module_code_size(ErtsCodeIndex code_ix)
 
 int module_table_sz(void)
 {
-    return erts_smp_atomic_read_nob(&tot_module_bytes);
+    return erts_atomic_read_nob(&tot_module_bytes);
 }
 
 #ifdef DEBUG
@@ -233,7 +231,7 @@ void module_start_staging(void)
         copy_module(dst_mod, src_mod);
     }
     newsz = index_table_sz(dst);
-    erts_smp_atomic_add_nob(&tot_module_bytes, (newsz - oldsz));
+    erts_atomic_add_nob(&tot_module_bytes, (newsz - oldsz));
 
     entries_at_start_staging = dst->entries;
     IF_DEBUG(dbg_load_code_ix = erts_staging_code_ix());
@@ -251,7 +249,7 @@ void module_end_staging(int commit)
 	oldsz = index_table_sz(tab);
 	index_erase_latest_from(tab, entries_at_start_staging);
 	newsz = index_table_sz(tab);
-	erts_smp_atomic_add_nob(&tot_module_bytes, (newsz - oldsz));
+	erts_atomic_add_nob(&tot_module_bytes, (newsz - oldsz));
     }
 
     IF_DEBUG(dbg_load_code_ix = -1);
diff --git a/erts/emulator/beam/module.h b/erts/emulator/beam/module.h
index 9d258d5dbf..a3f1ce1705 100644
--- a/erts/emulator/beam/module.h
+++ b/erts/emulator/beam/module.h
@@ -45,7 +45,7 @@ typedef struct erl_module {
     int seen;			/* Used by finish_loading() */
 
     struct erl_module_instance curr;
-    struct erl_module_instance old; /* protected by "old_code" rwlock */
+    struct erl_module_instance old; /* active protected by "old_code" rwlock */
     struct erl_module_instance* on_load;
 } Module; 
 
@@ -72,29 +72,29 @@ int erts_is_old_code_rlocked(ErtsCodeIndex);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
-extern erts_smp_rwmtx_t the_old_code_rwlocks[ERTS_NUM_CODE_IX];
+extern erts_rwmtx_t the_old_code_rwlocks[ERTS_NUM_CODE_IX];
 
 ERTS_GLB_INLINE void erts_rwlock_old_code(ErtsCodeIndex code_ix)
 {
-    erts_smp_rwmtx_rwlock(&the_old_code_rwlocks[code_ix]);
+    erts_rwmtx_rwlock(&the_old_code_rwlocks[code_ix]);
 }
 ERTS_GLB_INLINE void erts_rwunlock_old_code(ErtsCodeIndex code_ix)
 {
-    erts_smp_rwmtx_rwunlock(&the_old_code_rwlocks[code_ix]);
+    erts_rwmtx_rwunlock(&the_old_code_rwlocks[code_ix]);
 }
 ERTS_GLB_INLINE void erts_rlock_old_code(ErtsCodeIndex code_ix)
 {
-    erts_smp_rwmtx_rlock(&the_old_code_rwlocks[code_ix]);
+    erts_rwmtx_rlock(&the_old_code_rwlocks[code_ix]);
 }
 ERTS_GLB_INLINE void erts_runlock_old_code(ErtsCodeIndex code_ix)
 {
-    erts_smp_rwmtx_runlock(&the_old_code_rwlocks[code_ix]);
+    erts_rwmtx_runlock(&the_old_code_rwlocks[code_ix]);
 }
 
 #ifdef ERTS_ENABLE_LOCK_CHECK
 ERTS_GLB_INLINE int erts_is_old_code_rlocked(ErtsCodeIndex code_ix)
 {
-    return erts_smp_lc_rwmtx_is_rlocked(&the_old_code_rwlocks[code_ix]);
+    return erts_lc_rwmtx_is_rlocked(&the_old_code_rwlocks[code_ix]);
 }
 #endif
 
diff --git a/erts/emulator/beam/msg_instrs.tab b/erts/emulator/beam/msg_instrs.tab
new file mode 100644
index 0000000000..d6d4d2fb49
--- /dev/null
+++ b/erts/emulator/beam/msg_instrs.tab
@@ -0,0 +1,387 @@
+// -*- c -*-
+//
+// %CopyrightBegin%
+//
+// Copyright Ericsson AB 2017. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// %CopyrightEnd%
+//
+
+// /*
+//  * Skeleton for receive statement:
+//  *
+//  *             recv_mark L1                     Optional
+//  *             call make_ref/monitor            Optional
+//  *             ...
+//  *             recv_set L1                      Optional
+//  *      L1:          <-------------------+
+//  *                   <-----------+       |
+//  *                               |       |
+//  *             loop_rec L2 ------+---+   |
+//  *             ...               |   |   |
+//  *             remove_message    |   |   |
+//  *             jump L3           |   |   |
+//  *		...                 |   |   |
+//  *		loop_rec_end L1   --+   |   |
+//  *      L2:          <---------------+   |
+//  *	   	wait L1  -------------------+      or wait_timeout
+//  *		timeout
+//  *
+//  *	 L3:    Code after receive...
+//  *
+//  */
+
+i_recv_mark() {
+    /*
+     * Save the current position in message buffer.
+     */
+    c_p->msg.saved_last = c_p->msg.last;
+}
+
+i_recv_set() {
+    /*
+     * If c_p->msg.saved_last is non-zero, it points to the first
+     * message that could possibly be matched out.
+     *
+     * If c_p->msg.saved_last is zero, it means that it was invalidated
+     * because another receive was executed before this i_recv_set()
+     * instruction was reached.
+     */
+    if (c_p->msg.saved_last) {
+        c_p->msg.save = c_p->msg.saved_last;
+    }
+    SET_I($NEXT_INSTRUCTION);
+    goto loop_rec_top__;
+    //| -no_next
+}
+
+i_loop_rec(Dest) {
+    //| -no_prefetch
+
+    /*
+     * Pick up the next message and place it in x(0).
+     * If no message, jump to a wait or wait_timeout instruction.
+     */
+
+    ErtsMessage* msgp;
+
+    /* Entry point from recv_set */
+ loop_rec_top__:
+    ;
+
+    /*
+     * We need to disable GC while matching messages
+     * in the queue. This since messages with data outside
+     * the heap will be corrupted by a GC.
+     */
+    ASSERT(!(c_p->flags & F_DELAY_GC));
+    c_p->flags |= F_DELAY_GC;
+
+    /* Entry point from loop_rec_end */
+ loop_rec__:
+
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+
+    msgp = PEEK_MESSAGE(c_p);
+
+    if (!msgp) {
+        erts_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+        /* Make sure messages wont pass exit signals... */
+        if (ERTS_PROC_PENDING_EXIT(c_p)) {
+            erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+            SWAPOUT;
+            c_p->flags &= ~F_DELAY_GC;
+            c_p->arity = 0;
+            goto do_schedule; /* Will be rescheduled for exit */
+        }
+        ERTS_MSGQ_MV_INQ2PRIVQ(c_p);
+        msgp = PEEK_MESSAGE(c_p);
+        if (msgp) {
+            erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+        } else {
+            c_p->flags &= ~F_DELAY_GC;
+            $SET_I_REL($Dest);
+            Goto(*I);		/* Jump to a wait or wait_timeout instruction */
+        }
+    }
+    if (is_non_value(ERL_MESSAGE_TERM(msgp))) {
+        SWAPOUT; /* erts_decode_dist_message() may write to heap... */
+        if (!erts_decode_dist_message(c_p, ERTS_PROC_LOCK_MAIN, msgp, 0)) {
+            /*
+             * A corrupt distribution message that we weren't able to decode;
+             * remove it...
+             */
+            /* No swapin should be needed */
+            ASSERT(HTOP == c_p->htop && E == c_p->stop);
+            /* TODO: Add DTrace probe for this bad message situation? */
+            UNLINK_MESSAGE(c_p, msgp);
+            c_p->msg.saved_last = 0; /* Better safe than sorry. */
+            msgp->next = NULL;
+            erts_cleanup_messages(msgp);
+            goto loop_rec__;
+        }
+        SWAPIN;
+    }
+    r(0) = ERL_MESSAGE_TERM(msgp);
+}
+
+remove_message() {
+    //| -no_prefetch
+
+    /*
+     * Remove a (matched) message from the message queue.
+     */
+
+    ErtsMessage* msgp;
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+
+    ERTS_CHK_MBUF_SZ(c_p);
+
+    msgp = PEEK_MESSAGE(c_p);
+
+    if (ERTS_PROC_GET_SAVED_CALLS_BUF(c_p)) {
+        save_calls(c_p, &exp_receive);
+    }
+    if (ERL_MESSAGE_TOKEN(msgp) == NIL) {
+#ifdef USE_VM_PROBES
+        if (DT_UTAG(c_p) != NIL) {
+            if (DT_UTAG_FLAGS(c_p) & DT_UTAG_PERMANENT) {
+                SEQ_TRACE_TOKEN(c_p) = am_have_dt_utag;
+            } else {
+                DT_UTAG(c_p) = NIL;
+                SEQ_TRACE_TOKEN(c_p) = NIL;
+            }
+        } else {
+#endif
+            SEQ_TRACE_TOKEN(c_p) = NIL;
+#ifdef USE_VM_PROBES
+        }
+        DT_UTAG_FLAGS(c_p) &= ~DT_UTAG_SPREADING;
+#endif
+    } else if (ERL_MESSAGE_TOKEN(msgp) != am_undefined) {
+        Eterm msg;
+        SEQ_TRACE_TOKEN(c_p) = ERL_MESSAGE_TOKEN(msgp);
+#ifdef USE_VM_PROBES
+        if (ERL_MESSAGE_TOKEN(msgp) == am_have_dt_utag) {
+            if (DT_UTAG(c_p) == NIL) {
+                DT_UTAG(c_p) = ERL_MESSAGE_DT_UTAG(msgp);
+            }
+            DT_UTAG_FLAGS(c_p) |= DT_UTAG_SPREADING;
+        } else {
+#endif
+            ASSERT(is_tuple(SEQ_TRACE_TOKEN(c_p)));
+            ASSERT(SEQ_TRACE_TOKEN_ARITY(c_p) == 5);
+            ASSERT(is_small(SEQ_TRACE_TOKEN_SERIAL(c_p)));
+            ASSERT(is_small(SEQ_TRACE_TOKEN_LASTCNT(c_p)));
+            ASSERT(is_small(SEQ_TRACE_TOKEN_FLAGS(c_p)));
+            ASSERT(is_pid(SEQ_TRACE_TOKEN_SENDER(c_p)));
+            c_p->seq_trace_lastcnt = unsigned_val(SEQ_TRACE_TOKEN_SERIAL(c_p));
+            if (c_p->seq_trace_clock < unsigned_val(SEQ_TRACE_TOKEN_SERIAL(c_p))) {
+                c_p->seq_trace_clock = unsigned_val(SEQ_TRACE_TOKEN_SERIAL(c_p));
+            }
+            msg = ERL_MESSAGE_TERM(msgp);
+            seq_trace_output(SEQ_TRACE_TOKEN(c_p), msg, SEQ_TRACE_RECEIVE, 
+                             c_p->common.id, c_p);
+#ifdef USE_VM_PROBES
+        }
+#endif
+    }
+#ifdef USE_VM_PROBES
+    if (DTRACE_ENABLED(message_receive)) {
+        Eterm token2 = NIL;
+        DTRACE_CHARBUF(receiver_name, DTRACE_TERM_BUF_SIZE);
+        Sint tok_label = 0;
+        Sint tok_lastcnt = 0;
+        Sint tok_serial = 0;
+
+        dtrace_proc_str(c_p, receiver_name);
+        token2 = SEQ_TRACE_TOKEN(c_p);
+        if (have_seqtrace(token2)) {
+            tok_label = signed_val(SEQ_TRACE_T_LABEL(token2));
+            tok_lastcnt = signed_val(SEQ_TRACE_T_LASTCNT(token2));
+            tok_serial = signed_val(SEQ_TRACE_T_SERIAL(token2));
+        }
+        DTRACE6(message_receive,
+                receiver_name, size_object(ERL_MESSAGE_TERM(msgp)),
+                c_p->msg.len - 1, tok_label, tok_lastcnt, tok_serial);
+    }
+#endif
+    UNLINK_MESSAGE(c_p, msgp);
+    JOIN_MESSAGE(c_p);
+    CANCEL_TIMER(c_p);
+
+    erts_save_message_in_proc(c_p, msgp);
+    c_p->flags &= ~F_DELAY_GC;
+
+    if (ERTS_IS_GC_DESIRED_INTERNAL(c_p, HTOP, E)) {
+        /*
+         * We want to GC soon but we leave a few
+         * reductions giving the message some time
+         * to turn into garbage.
+         */
+        ERTS_VBUMP_LEAVE_REDS_INTERNAL(c_p, 5, FCALLS);
+    }
+
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    ERTS_CHK_MBUF_SZ(c_p);
+
+    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+    PROCESS_MAIN_CHK_LOCKS(c_p);
+}
+
+loop_rec_end(Dest) {
+    //| -no_next
+    /*
+     * Advance the save pointer to the next message (the current
+     * message didn't match), then jump to the loop_rec instruction.
+     */
+
+    ASSERT(c_p->flags & F_DELAY_GC);
+
+    $SET_I_REL($Dest);
+    SAVE_MESSAGE(c_p);
+    if (FCALLS > 0 || FCALLS > neg_o_reds) {
+        FCALLS--;
+        goto loop_rec__;
+    }
+
+    c_p->flags &= ~F_DELAY_GC;
+    $SET_CP_I_ABS(I);
+    SWAPOUT;
+    c_p->arity = 0;
+    c_p->current = NULL;
+    goto do_schedule;
+}
+
+timeout_locked() {
+    /*
+     * A timeout has occurred.  Reset the save pointer so that the next
+     * receive statement will examine the first message first.
+     */
+
+    erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+    $timeout();
+}
+
+timeout() {
+    if (IS_TRACED_FL(c_p, F_TRACE_RECEIVE)) {
+        trace_receive(c_p, am_clock_service, am_timeout, NULL);
+    }
+    if (ERTS_PROC_GET_SAVED_CALLS_BUF(c_p)) {
+        save_calls(c_p, &exp_timeout);
+    }
+    c_p->flags &= ~F_TIMO;
+    JOIN_MESSAGE(c_p);
+}
+
+TIMEOUT_VALUE() {
+    c_p->freason = EXC_TIMEOUT_VALUE;
+    goto find_func_info;
+    //| -no_next
+}
+
+i_wait_error_locked() {
+    erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+    $TIMEOUT_VALUE();
+}
+
+i_wait_error() {
+    $TIMEOUT_VALUE();
+}
+
+wait_timeout_unlocked_int := wait.lock.int.execute;
+wait_timeout_locked_int := wait.int.execute;
+
+wait_timeout_unlocked := wait.lock.src.execute;
+wait_timeout_locked := wait.src.execute;
+
+wait_unlocked := wait.lock.execute;
+wait_locked := wait.unlocked.execute;
+
+wait.lock() {
+    erts_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+}
+
+wait.unlocked() {
+}
+
+wait.int(Int) {
+    /*
+     * If we have already set the timer, we must NOT set it again.  Therefore,
+     * we must test the F_INSLPQUEUE flag as well as the F_TIMO flag.
+     */
+    if ((c_p->flags & (F_INSLPQUEUE | F_TIMO)) == 0) {
+        BeamInstr** pi = (BeamInstr **) c_p->def_arg_reg;
+        *pi = $NEXT_INSTRUCTION;
+        erts_set_proc_timer_uword(c_p, $Int);
+    }
+}
+
+wait.src(Src) {
+    /*
+     * If we have already set the timer, we must NOT set it again.  Therefore,
+     * we must test the F_INSLPQUEUE flag as well as the F_TIMO flag.
+     */
+    if ((c_p->flags & (F_INSLPQUEUE | F_TIMO)) == 0) {
+        Eterm timeout_value = $Src;
+        if (timeout_value == make_small(0)) {
+            erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+            $NEXT0();
+        } else if (timeout_value == am_infinity) {
+            c_p->flags |= F_TIMO;
+        } else {
+            int tres = erts_set_proc_timer_term(c_p, timeout_value);
+            if (tres == 0) {
+                /*
+                 * The timer routiner will set c_p->i to the value in
+                 * c_p->def_arg_reg[0].  Note that it is safe to use this
+                 * location because there are no living x registers in
+                 * a receive statement.
+                 */
+                BeamInstr** pi = (BeamInstr**) c_p->def_arg_reg;
+                *pi = $NEXT_INSTRUCTION;
+            } else { /* Wrong time */
+                erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+                c_p->freason = EXC_TIMEOUT_VALUE;
+                goto find_func_info;
+            }
+        }
+    }
+}
+
+//
+// Prepare to wait indefinitely for a new message to arrive
+// (or the time set above if falling through from above).
+// When a new message arrives, control will be transferred
+// the loop_rec instruction (at label L1).  In case of
+// of timeout, control will be transferred to the timeout
+// instruction following the wait_timeout instruction.
+//
+
+wait.execute(JumpTarget) {
+    $SET_REL_I(c_p->i, $JumpTarget); /* L1 */
+    SWAPOUT;
+    c_p->arity = 0;
+
+    if (!ERTS_PTMR_IS_TIMED_OUT(c_p)) {
+        erts_atomic32_read_band_relb(&c_p->state,
+                                         ~ERTS_PSFLG_ACTIVE);
+    }
+    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
+    erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+    c_p->current = NULL;
+    goto do_schedule;
+    //| -no_next
+}
diff --git a/erts/emulator/beam/ops.tab b/erts/emulator/beam/ops.tab
index 44613c7d85..fd1b3b9c74 100644
--- a/erts/emulator/beam/ops.tab
+++ b/erts/emulator/beam/ops.tab
@@ -59,6 +59,7 @@ put_tuple u==0 d => too_old_compiler
 # All the other instructions.
 #
 
+%cold
 label L
 i_func_info I a a I
 int_code_end
@@ -68,6 +69,8 @@ i_debug_breakpoint
 i_return_time_trace
 i_return_to_trace
 i_yield
+trace_jump W
+%hot
 
 return
 
@@ -96,24 +99,21 @@ line Loc | func_info M F A => func_info M F A | line Loc
 
 line I
 
+allocate t t?
+allocate_heap t I t?
 
-%macro: allocate Allocate -pack
-%macro: allocate_zero AllocateZero -pack
-%macro: allocate_heap AllocateHeap -pack
-%macro: allocate_heap_zero AllocateHeapZero -pack
-%macro: test_heap TestHeap -pack
+%cold
+deallocate Q
+%hot
 
-allocate t t
-allocate_heap t I t
-deallocate I
 init y
-allocate_zero t t
-allocate_heap_zero t I t
+allocate_zero t t?
+allocate_heap_zero t I t?
 
 trim N Remaining => i_trim N
-i_trim I
+i_trim t
 
-test_heap I t
+test_heap I t?
 
 allocate_heap S u==0 R => allocate S R
 allocate_heap_zero S u==0 R => allocate_zero S R
@@ -122,8 +122,6 @@ init2 y y
 init3 y y y
 init Y1 | init Y2 | init Y3 => init3 Y1 Y2 Y3
 init Y1 | init Y2 => init2 Y1 Y2
-%macro: init2 Init2 -pack
-%macro: init3 Init3 -pack
 
 # Selecting values
 
@@ -160,28 +158,20 @@ is_tuple Fail=f S | select_tuple_arity S=d Fail=f Size=u Rest=* => \
 select_tuple_arity S=d Fail=f Size=u Rest=* => \
   gen_select_tuple_arity(S, Fail, Size, Rest)
 
-i_select_val_bins x f I
-i_select_val_bins y f I
+i_select_val_bins xy f? I
 
-i_select_val_lins x f I
-i_select_val_lins y f I
+i_select_val_lins xy f? I
 
-i_select_val2 x f c c f f
-i_select_val2 y f c c f f
+i_select_val2 xy f? c c
 
-i_select_tuple_arity x f I
-i_select_tuple_arity y f I
+i_select_tuple_arity xy f? I
 
-i_select_tuple_arity2 x f A A f f
-i_select_tuple_arity2 y f A A f f
+i_select_tuple_arity2 xy f? A A
 
-i_jump_on_val_zero x f I
-i_jump_on_val_zero y f I
+i_jump_on_val_zero xy f? I
 
-i_jump_on_val x f I I
-i_jump_on_val y f I I
+i_jump_on_val xy f? I W
 
-%macro: get_list GetList -pack
 get_list xy xy xy
 
 # The following get_list instructions using x(0) are frequently used.
@@ -198,44 +188,46 @@ catch_end y
 
 # Try/catch.
 try Y F => catch Y F
-try_case Y => try_end Y
+
+try_case y
 try_end y
 
+%cold
 try_case_end s
+%hot
 
 # Destructive set tuple element
 
-set_tuple_element s d P
+set_tuple_element s S P
 
 # Get tuple element
 
-%macro: i_get_tuple_element GetTupleElement -pack
 i_get_tuple_element xy P x
 
 %cold
 i_get_tuple_element xy P y
 %hot
 
-%macro: i_get_tuple_element2 GetTupleElement2 -pack
 i_get_tuple_element2 x P x
-
-%macro: i_get_tuple_element2y GetTupleElement2Y -pack
 i_get_tuple_element2y x P y y
 
-%macro: i_get_tuple_element3 GetTupleElement3 -pack
 i_get_tuple_element3 x P x
 
-%macro: is_number IsNumber -fail_action
 %cold
-is_number f x
-is_number f y
+is_number f? xy
 %hot
+
 is_number Fail=f i =>
 is_number Fail=f na => jump Fail
 is_number Fail Literal=q => move Literal x | is_number Fail x
 
 jump f
 
+#
+# Expection rasing instructions. Infrequently executed.
+#
+
+%cold
 case_end NotInX=cy => move NotInX x | case_end x
 badmatch NotInX=cy => move NotInX x | badmatch x
 
@@ -257,9 +249,14 @@ i_raise
 badarg j
 system_limit j
 
+%hot
+
+#
+# Move instructions.
+#
+
 move C=cxy x==0 | jump Lbl => move_jump Lbl C
 
-%macro: move_jump MoveJump -nonext
 move_jump f ncxy
 
 # Movement to and from the stack is common
@@ -283,10 +280,6 @@ move_window X1=x X2=x X3=x X4=x Y1=y Y4=y | move X5=x Y5=y | succ(Y4,Y5) => \
 move_window X1=x X2=x X3=x Y1=y Y3=y => move_window3 X1 X2 X3 Y1
 move_window X1=x X2=x X3=x X4=x Y1=y Y4=y => move_window4 X1 X2 X3 X4 Y1
 
-%macro: move_window3 MoveWindow3 -pack
-%macro: move_window4 MoveWindow4 -pack
-%macro: move_window5 MoveWindow5 -pack
-
 move_window3 x x x y
 move_window4 x x x x y
 move_window5 x x x x x y
@@ -311,10 +304,8 @@ swap_temp R1 R2 Tmp | line Loc | call_ext_only Live Addr | \
 swap_temp R1 R2 Tmp | line Loc | call_ext_last Live Addr D | \
   is_killed(Tmp, Live) => swap R1 R2 | line Loc | call_ext_last Live Addr D
 
-%macro: swap_temp SwapTemp -pack
 swap_temp x xy x
 
-%macro: swap Swap -pack
 swap x xy
 
 move Src=x D1=x | move Src=x D2=x => move_dup Src D1 D2
@@ -358,17 +349,13 @@ move C=aiq X=x==2 => move_x2 C
 move_x1 c
 move_x2 c
 
-%macro: move_shift MoveShift -pack
 move_shift x x x
 move_shift y x x
 move_shift x y x
 move_shift x x y
 
-%macro: move_dup MoveDup -pack
 move_dup xy x xy
 
-%macro: move2_par Move2Par -pack
-
 move2_par x y x y
 move2_par y x y x
 move2_par x x x x
@@ -380,7 +367,6 @@ move2_par y x x y
 move2_par x x y x
 move2_par y x x x
 
-%macro: move3 Move3 -pack
 move3 x y x y x y
 move3 y x y x y x
 move3 x x x x x x
@@ -390,7 +376,6 @@ move3 x x x x x x
 move S=n D=y => init D
 move S=c D=y => move S x | move x D
 
-%macro:move Move -pack
 move x x
 move x y
 move y x
@@ -410,13 +395,15 @@ move r y
 
 loop_rec Fail x==0 | smp_mark_target_label(Fail) => i_loop_rec Fail
 
-label L | wait_timeout Fail Src | smp_already_locked(L) => label L | i_wait_timeout_locked Fail Src
-wait_timeout Fail Src => i_wait_timeout Fail Src
-i_wait_timeout Fail Src=aiq => gen_literal_timeout(Fail, Src)
-i_wait_timeout_locked Fail Src=aiq => gen_literal_timeout_locked(Fail, Src)
+label L | wait_timeout Fail Src | smp_already_locked(L) => \
+    label L | wait_timeout_locked Src Fail
+wait_timeout Fail Src => wait_timeout_unlocked Src Fail
+
+wait_timeout_unlocked Src=aiq Fail => gen_literal_timeout(Fail, Src)
+wait_timeout_locked Src=aiq Fail => gen_literal_timeout_locked(Fail, Src)
 
 label L | wait Fail | smp_already_locked(L) => label L | wait_locked Fail
-wait Fail | smp() => wait_unlocked Fail
+wait Fail => wait_unlocked Fail
 
 label L | timeout | smp_already_locked(L) => label L | timeout_locked
 
@@ -425,15 +412,19 @@ timeout
 timeout_locked
 i_loop_rec f
 loop_rec_end f
-wait f
 wait_locked f
 wait_unlocked f
-i_wait_timeout f I
-i_wait_timeout f s
-i_wait_timeout_locked f I
-i_wait_timeout_locked f s
+
+# Note that a timeout value must fit in 32 bits.
+wait_timeout_unlocked_int I f
+wait_timeout_unlocked s f
+wait_timeout_locked_int I f
+wait_timeout_locked s f
+
+%cold
 i_wait_error
 i_wait_error_locked
+%hot
 
 send
 
@@ -441,56 +432,52 @@ send
 # Optimized comparisons with one immediate/literal operand.
 #
 
-is_eq_exact Lbl R=xy C=ian => i_is_eq_exact_immed Lbl R C
+is_eq_exact Lbl S S =>
+is_eq_exact Lbl C1=c C2=c => move C1 x | is_eq_exact Lbl x C2
+is_eq_exact Lbl C=c R=xy => is_eq_exact Lbl R C
+
+is_eq_exact Lbl R=xy n => is_nil Lbl R
+is_eq_exact Lbl R=xy C=ia => i_is_eq_exact_immed Lbl R C
 is_eq_exact Lbl R=xy C=q => i_is_eq_exact_literal Lbl R C
 
+is_ne_exact Lbl S S => jump Lbl
+is_ne_exact Lbl C1=c C2=c => move C1 x | is_ne_exact Lbl x C2
+is_ne_exact Lbl C=c R=xy => is_ne_exact Lbl R C
+
 is_ne_exact Lbl R=xy C=ian => i_is_ne_exact_immed Lbl R C
 is_ne_exact Lbl R=xy C=q => i_is_ne_exact_literal Lbl R C
 
-%macro: i_is_eq_exact_immed EqualImmed -fail_action
-i_is_eq_exact_immed f r c
-i_is_eq_exact_immed f x c
-i_is_eq_exact_immed f y c
+i_is_eq_exact_immed f? rxy c
 
-i_is_eq_exact_literal f x c
-i_is_eq_exact_literal f y c
+i_is_eq_exact_literal f? xy c
 
-%macro: i_is_ne_exact_immed NotEqualImmed -fail_action
-i_is_ne_exact_immed f x c
-i_is_ne_exact_immed f y c
+i_is_ne_exact_immed f? xy c
 
-i_is_ne_exact_literal f x c
-i_is_ne_exact_literal f y c
+i_is_ne_exact_literal f? xy c
 
 is_eq_exact Lbl Y=y X=x => is_eq_exact Lbl X Y
-%macro: is_eq_exact EqualExact -fail_action -pack
-is_eq_exact f x xy
-is_eq_exact f s s
-
-%macro: is_lt IsLessThan -fail_action
-is_lt f x x
-is_lt f x c
-is_lt f c x
+is_eq_exact f? x xy
+is_eq_exact f? y y
+
+is_ne_exact f? S S
+
+is_lt f? x x
+is_lt f? x c
+is_lt f? c x
 %cold
-is_lt f s s
+is_lt f? s s
 %hot
 
-%macro: is_ge IsGreaterEqual -fail_action
-is_ge f x x
-is_ge f x c
-is_ge f c x
+is_ge f? x x
+is_ge f? x c
+is_ge f? c x
 %cold
-is_ge f s s
+is_ge f? s s
 %hot
 
-%macro: is_ne_exact NotEqualExact -fail_action
-is_ne_exact f s s
-
-%macro: is_eq Equal -fail_action
-is_eq f s s
+is_eq f? s s
 
-%macro: is_ne NotEqual -fail_action
-is_ne f s s
+is_ne f? s s
 
 #
 # Putting things.
@@ -507,9 +494,7 @@ i_put_tuple Dst Arity Puts=* | put S => \
 
 i_put_tuple/2
 
-%macro:i_put_tuple PutTuple -pack -goto:do_put_tuple
-i_put_tuple x I
-i_put_tuple y I
+i_put_tuple xy I
 
 #
 # The instruction "put_list Const [] Dst" were generated in rare
@@ -518,7 +503,9 @@ i_put_tuple y I
 #
 put_list Const=c n Dst => move Const x | put_list x n Dst
 
-%macro:put_list PutList -pack
+put_list Src Dst=x Dst => update_list Src Dst
+
+update_list xyc x
 
 put_list x n x
 put_list y n x
@@ -528,8 +515,6 @@ put_list y x x
 put_list y y x
 put_list x y x
 
-put_list y x x
-
 # put_list SrcReg Constant Dst
 
 put_list x c x
@@ -544,8 +529,6 @@ put_list c y x
 
 # The following put_list instructions using x(0) are frequently used.
 
-put_list y r r
-put_list x r r
 put_list r n r
 put_list r n x
 put_list r x x
@@ -556,10 +539,12 @@ put_list x x r
 put_list s s d
 %hot
 
+
 #
 # Some more only used by the emulator
 #
 
+%cold
 normal_exit
 continue_exit
 apply_bif
@@ -567,6 +552,7 @@ call_nif
 call_error_handler
 error_action_code
 return_trace
+%hot
 
 #
 # Instruction transformations & folded instructions.
@@ -577,27 +563,18 @@ return_trace
 
 move S x==0 | return => move_return S
 
-%macro: move_return MoveReturn -nonext
-move_return x
-move_return c
-move_return n
+move_return xcn
 
 move S x==0 | deallocate D | return => move_deallocate_return S D
 
-%macro: move_deallocate_return MoveDeallocateReturn -pack -nonext
-move_deallocate_return x Q
-move_deallocate_return y Q
-move_deallocate_return c Q
-move_deallocate_return n Q
+move_deallocate_return xycn Q
 
 deallocate D | return => deallocate_return D
 
-%macro: deallocate_return DeallocateReturn -nonext
 deallocate_return Q
 
 test_heap Need u==1 | put_list Y=y x==0 x==0 => test_heap_1_put_list Need Y
 
-%macro: test_heap_1_put_list TestHeapPutList -pack
 test_heap_1_put_list I y
 
 #
@@ -608,9 +585,7 @@ is_tagged_tuple Fail Literal=q Arity Atom => \
     move Literal x | is_tagged_tuple Fail x Arity Atom
 is_tagged_tuple Fail=f c Arity Atom  => jump Fail
 
-%macro:is_tagged_tuple IsTaggedTuple -fail_action
-
-is_tagged_tuple f rxy A a
+is_tagged_tuple f? rxy A a
 
 # Test tuple & arity (head)
 
@@ -618,18 +593,14 @@ is_tuple Fail Literal=q => move Literal x | is_tuple Fail x
 is_tuple Fail=f c => jump Fail
 is_tuple Fail=f S=xy | test_arity Fail=f S=xy Arity => is_tuple_of_arity Fail S Arity
 
-%macro:is_tuple_of_arity IsTupleOfArity -fail_action
-
-is_tuple_of_arity f rxy A
+is_tuple_of_arity f? rxy A
 
-%macro: is_tuple IsTuple -fail_action
-is_tuple f rxy
+is_tuple f? rxy
 
 test_arity Fail Literal=q Arity => move Literal x | test_arity Fail x Arity
 test_arity Fail=f c Arity => jump Fail
 
-%macro: test_arity IsArity -fail_action
-test_arity f xy A
+test_arity f? xy A
 
 get_tuple_element Reg=x P1 D1=x | get_tuple_element Reg=x P2 D2=x | \
    get_tuple_element Reg=x P3 D3=x | \
@@ -650,52 +621,40 @@ is_integer Fail Literal=q => move Literal x | is_integer Fail x
 
 is_integer Fail=f S=x | allocate Need Regs => is_integer_allocate Fail S Need Regs
 
-%macro: is_integer_allocate IsIntegerAllocate -fail_action
-is_integer_allocate f x I I
+is_integer_allocate f? x t t
 
-%macro: is_integer IsInteger -fail_action
-is_integer f xy
+is_integer f? xy
 
 is_list Fail=f n =>
 is_list Fail Literal=q => move Literal x | is_list Fail x
 is_list Fail=f c => jump Fail
-%macro: is_list IsList -fail_action
-is_list f x
+is_list f? x
 %cold
-is_list f y
+is_list f? y
 %hot
 
 is_nonempty_list Fail=f S=x | allocate Need Rs => is_nonempty_list_allocate Fail S Need Rs
 
-%macro:is_nonempty_list_allocate IsNonemptyListAllocate -fail_action -pack
-is_nonempty_list_allocate f rx I t
-
-is_nonempty_list F=f x==0 | test_heap I1 I2 => is_non_empty_list_test_heap F I1 I2
-
-%macro: is_non_empty_list_test_heap IsNonemptyListTestHeap -fail_action -pack
-is_non_empty_list_test_heap f I t
+is_nonempty_list F=f x==0 | test_heap I1 I2 => is_nonempty_list_test_heap F I1 I2
 
 is_nonempty_list Fail=f S=x | get_list S D1=x D2=x => \
   is_nonempty_list_get_list Fail S D1 D2
 
-%macro: is_nonempty_list_get_list IsNonemptyListGetList -fail_action -pack
-is_nonempty_list_get_list f rx x x
-
-%macro: is_nonempty_list IsNonemptyList -fail_action
-is_nonempty_list f xy
+is_nonempty_list_allocate f? rx t t
+is_nonempty_list_test_heap f? I t
+is_nonempty_list_get_list f? rx x x
+is_nonempty_list f? xy
 
-%macro: is_atom IsAtom -fail_action
-is_atom f x
+is_atom f? x
 %cold
-is_atom f y
+is_atom f? y
 %hot
 is_atom Fail=f a =>
 is_atom Fail=f niq => jump Fail
 
-%macro: is_float IsFloat -fail_action
-is_float f x
+is_float f? x
 %cold
-is_float f y
+is_float f? y
 %hot
 is_float Fail=f nai => jump Fail
 is_float Fail Literal=q => move Literal x | is_float Fail x
@@ -703,15 +662,13 @@ is_float Fail Literal=q => move Literal x | is_float Fail x
 is_nil Fail=f n =>
 is_nil Fail=f qia => jump Fail
 
-%macro: is_nil IsNil -fail_action
-is_nil f xy
+is_nil f? xy
 
 is_binary Fail Literal=q => move Literal x | is_binary Fail x
 is_binary Fail=f c => jump Fail
-%macro: is_binary IsBinary -fail_action
-is_binary f x
+is_binary f? x
 %cold
-is_binary f y
+is_binary f? y
 %hot
 
 # XXX Deprecated.
@@ -719,31 +676,27 @@ is_bitstr Fail Term => is_bitstring Fail Term
 
 is_bitstring Fail Literal=q => move Literal x | is_bitstring Fail x
 is_bitstring Fail=f c => jump Fail
-%macro: is_bitstring IsBitstring -fail_action
-is_bitstring f x
+is_bitstring f? x
 %cold
-is_bitstring f y
+is_bitstring f? y
 %hot
 
 is_reference Fail=f cq => jump Fail
-%macro: is_reference IsRef -fail_action
-is_reference f x
+is_reference f? x
 %cold
-is_reference f y
+is_reference f? y
 %hot
 
 is_pid Fail=f cq => jump Fail
-%macro: is_pid IsPid -fail_action
-is_pid f x
+is_pid f? x
 %cold
-is_pid f y
+is_pid f? y
 %hot
 
 is_port Fail=f cq => jump Fail
-%macro: is_port IsPort -fail_action
-is_port f x
+is_port f? x
 %cold
-is_port f y
+is_port f? y
 %hot
 
 is_boolean Fail=f a==am_true =>
@@ -751,22 +704,19 @@ is_boolean Fail=f a==am_false =>
 is_boolean Fail=f ac => jump Fail
 
 %cold
-%macro: is_boolean IsBoolean -fail_action
-is_boolean f xy
+is_boolean f? xy
 %hot
 
 is_function2 Fail=f acq Arity => jump Fail
 is_function2 Fail=f Fun a => jump Fail
 
-is_function2 f s s
-%macro: is_function2 IsFunction2 -fail_action
+is_function2 f? S s
 
 # Allocating & initializing.
 allocate Need Regs | init Y => allocate_init Need Regs Y
 init Y1 | init Y2 => init2 Y1 Y2
 
-%macro: allocate_init AllocateInit -pack
-allocate_init t I y
+allocate_init t t? y
 
 #################################################################
 # External function and bif calls.
@@ -1013,16 +963,18 @@ call_ext_last Ar Func D => i_call_ext_last Func D
 call_ext_only Ar Func   => i_call_ext_only Func
 
 i_apply
-i_apply_last P
+i_apply_last Q
 i_apply_only
 
 i_apply_fun
-i_apply_fun_last P
+i_apply_fun_last Q
 i_apply_fun_only
 
+%cold
 i_hibernate
 
 i_perf_counter
+%hot
 
 call_bif e
 
@@ -1045,73 +997,57 @@ bif2 Fail Bif S1 S2 Dst => i_bif2 Fail Bif S1 S2 Dst
 i_get_hash c I d
 i_get s d
 
-%macro: self Self
 self xy
 
-%macro: node Node
 node x
 %cold
 node y
 %hot
 
-i_fast_element j x I d
-i_fast_element j y I d
+# Note: 'I' is sufficient because this instruction will only be used
+# if the arity fits in 24 bits.
+i_fast_element xy j? I d
 
-i_element j xy s d
+i_element xy j? s d
 
-bif1 f b s d
+bif1 f? b s d
 bif1_body b s d
-i_bif2 f b s s d
+i_bif2 f? b s s d
 i_bif2_body b s s d
 
 #
 # Internal calls.
 #
 
-move S=c x==0 | call Ar P=f => i_move_call S P
-move S=s x==0 | call Ar P=f => move_call S P
-
-i_move_call c f
+move S=cxy x==0 | call Ar P=f => move_call S P
 
-%macro:move_call MoveCall -arg_f -size -nonext
 move_call/2
+move_call cxy f
 
-move_call xy f
-
-move S=c x==0 | call_last Ar P=f D => i_move_call_last P D S
 move S x==0 | call_last Ar P=f D => move_call_last S P D
 
-i_move_call_last f P c
-
-%macro:move_call_last MoveCallLast -arg_f -nonext -pack
-
 move_call_last/3
-move_call_last xy f Q
+move_call_last cxy f Q
 
-move S=c x==0 | call_only Ar P=f => i_move_call_only P S
-move S=x x==0 | call_only Ar P=f => move_call_only S P
+move S=cx x==0 | call_only Ar P=f => move_call_only S P
 
-i_move_call_only f c
-
-%macro:move_call_only MoveCallOnly -arg_f -nonext
 move_call_only/2
-
-move_call_only x f
+move_call_only cx f
 
 call Ar Func        => i_call Func
 call_last Ar Func D => i_call_last Func D
 call_only Ar Func   => i_call_only Func
 
 i_call f
-i_call_last f P
+i_call_last f Q
 i_call_only f
 
 i_call_ext e
-i_call_ext_last e P
+i_call_ext_last e Q
 i_call_ext_only e
 
 i_move_call_ext c e
-i_move_call_ext_last e P c
+i_move_call_ext_last e Q c
 i_move_call_ext_only e c
 
 # Fun calls.
@@ -1119,18 +1055,16 @@ i_move_call_ext_only e c
 call_fun Arity | deallocate D | return => i_call_fun_last Arity D
 call_fun Arity => i_call_fun Arity
 
-i_call_fun I
-i_call_fun_last I P
+i_call_fun t
+i_call_fun_last t Q
 
 make_fun2 OldIndex=u => gen_make_fun2(OldIndex)
 
-%macro: i_make_fun MakeFun -pack
 %cold
-i_make_fun I t
+i_make_fun W t
 %hot
 
-%macro: is_function IsFunction -fail_action
-is_function f xy
+is_function f? xy
 is_function Fail=f c => jump Fail
 
 func_info M F A => i_func_info u M F A
@@ -1139,45 +1073,44 @@ func_info M F A => i_func_info u M F A
 # New bit syntax matching (R11B).
 # ================================================================
 
-%cold
+%warm
 bs_start_match2 Fail=f ica X Y D => jump Fail
 bs_start_match2 Fail Bin X Y D => i_bs_start_match2 Bin Fail X Y D
-i_bs_start_match2 xy f I I d
+i_bs_start_match2 xy f t t x
 
 bs_save2 Reg Index => gen_bs_save(Reg, Index)
-i_bs_save2 x I
+i_bs_save2 x t
 
 bs_restore2 Reg Index => gen_bs_restore(Reg, Index)
-i_bs_restore2 x I
+i_bs_restore2 x t
 
 # Matching integers
 bs_match_string Fail Ms Bits Val => i_bs_match_string Ms Fail Bits Val
 
-i_bs_match_string x f I I
+i_bs_match_string x f W W
 
 # Fetching integers from binaries.
 bs_get_integer2 Fail=f Ms=x Live=u Sz=sq Unit=u Flags=u Dst=d => \
 			gen_get_integer2(Fail, Ms, Live, Sz, Unit, Flags, Dst)
 
-i_bs_get_integer_small_imm x I f I d
-i_bs_get_integer_imm x I I f I d
-i_bs_get_integer f I I s s d
-i_bs_get_integer_8 x f d
-i_bs_get_integer_16 x f d
-i_bs_get_integer_32 x f I d
+i_bs_get_integer_small_imm x W f? t x
+i_bs_get_integer_imm x W t f? t x
+i_bs_get_integer f? t t x s x
+i_bs_get_integer_8 x f? x
+i_bs_get_integer_16 x f? x
+
+%if ARCH_64
+i_bs_get_integer_32 x f? x
+%endif
 
 # Fetching binaries from binaries.
 bs_get_binary2 Fail=f Ms=x Live=u Sz=sq Unit=u Flags=u Dst=d => \
 			gen_get_binary2(Fail, Ms, Live, Sz, Unit, Flags, Dst)
 
-%macro: i_bs_get_binary_imm2 BsGetBinaryImm_2 -fail_action
-%macro: i_bs_get_binary2 BsGetBinary_2 -fail_action
-%macro: i_bs_get_binary_all2 BsGetBinaryAll_2 -fail_action
-
-i_bs_get_binary_imm2 f x I I I x
-i_bs_get_binary2 f x I s I x
-i_bs_get_binary_all2 f x I I x
-i_bs_get_binary_all_reuse x f I
+i_bs_get_binary_imm2 f? x t W t x
+i_bs_get_binary2 f x t? s t x
+i_bs_get_binary_all2 f? x t t x
+i_bs_get_binary_all_reuse x f? t
 
 # Fetching float from binaries.
 bs_get_float2 Fail=f Ms=x Live=u Sz=s Unit=u Flags=u Dst=d => \
@@ -1185,35 +1118,32 @@ bs_get_float2 Fail=f Ms=x Live=u Sz=s Unit=u Flags=u Dst=d => \
 
 bs_get_float2 Fail=f Ms=x Live=u Sz=q Unit=u Flags=u Dst=d => jump Fail
 
-%macro: i_bs_get_float2 BsGetFloat2 -fail_action
-i_bs_get_float2 f x I s I x
+i_bs_get_float2 f? x t s t x
 
 # Miscellanous
 
 bs_skip_bits2 Fail=f Ms=x Sz=sq Unit=u Flags=u => \
 			gen_skip_bits2(Fail, Ms, Sz, Unit, Flags)
 
-%macro: i_bs_skip_bits_imm2 BsSkipBitsImm2 -fail_action
-i_bs_skip_bits_imm2 f x I
-
-%macro: i_bs_skip_bits2 BsSkipBits2 -fail_action
-i_bs_skip_bits2 f x xy I
-
-%macro: i_bs_skip_bits_all2 BsSkipBitsAll2 -fail_action
-i_bs_skip_bits_all2 f x I 
+i_bs_skip_bits_imm2 f? x W
+i_bs_skip_bits2 f? x xy t
+i_bs_skip_bits_all2 f? x t
 
 bs_test_tail2 Fail=f Ms=x Bits=u==0 => bs_test_zero_tail2 Fail Ms
 bs_test_tail2 Fail=f Ms=x Bits=u => bs_test_tail_imm2 Fail Ms Bits
-bs_test_zero_tail2 f x
-bs_test_tail_imm2 f x I
+bs_test_zero_tail2 f? x
+bs_test_tail_imm2 f? x W
 
 bs_test_unit F Ms Unit=u==8 => bs_test_unit8 F Ms
-bs_test_unit f x I
-bs_test_unit8 f x
+bs_test_unit f? x t
+bs_test_unit8 f? x
 
 # An y register operand for bs_context_to_binary is rare,
 # but can happen because of inlining.
 
+bs_context_to_binary Y=y | line L | badmatch Y => \
+    move Y x | bs_context_to_binary x | line L | badmatch x
+
 bs_context_to_binary Y=y => move Y x | bs_context_to_binary x
 
 bs_context_to_binary x
@@ -1222,14 +1152,14 @@ bs_context_to_binary x
 # Utf8/utf16/utf32 support. (R12B-5)
 #
 bs_get_utf8 Fail=f Ms=x u u Dst=d => i_bs_get_utf8 Ms Fail Dst
-i_bs_get_utf8 x f d
+i_bs_get_utf8 x f? x
 
 bs_skip_utf8 Fail=f Ms=x u u => i_bs_get_utf8 Ms Fail x
 
 bs_get_utf16 Fail=f Ms=x u Flags=u Dst=d => i_bs_get_utf16 Ms Fail Flags Dst
 bs_skip_utf16 Fail=f Ms=x u Flags=u => i_bs_get_utf16 Ms Fail Flags x
 
-i_bs_get_utf16 x f I d
+i_bs_get_utf16 x f? t x
 
 bs_get_utf32 Fail=f Ms=x Live=u Flags=u Dst=d => \
 	bs_get_integer2 Fail Ms Live i=32 u=1 Flags Dst | \
@@ -1238,22 +1168,18 @@ bs_skip_utf32 Fail=f Ms=x Live=u Flags=u => \
 	bs_get_integer2 Fail Ms Live i=32 u=1 Flags x | \
 	i_bs_validate_unicode_retract Fail x Ms
 
-i_bs_validate_unicode_retract j s s
+i_bs_validate_unicode_retract j s S
 %hot
 
 #
 # Constructing binaries
 #
-%cold
+%warm
 
 bs_init2 Fail Sz Words Regs Flags Dst | binary_too_big(Sz) => system_limit Fail
 
-bs_init2 Fail Sz=u Words=u==0 Regs Flags Dst | should_gen_heap_bin(Sz) => \
-	i_bs_init_heap_bin Sz Regs Dst
 bs_init2 Fail Sz=u Words=u==0 Regs Flags Dst => i_bs_init Sz Regs Dst
 
-bs_init2 Fail Sz=u Words Regs Flags Dst | should_gen_heap_bin(Sz) => \
-	i_bs_init_heap_bin_heap Sz Words Regs Dst
 bs_init2 Fail Sz=u Words Regs Flags Dst => \
    i_bs_init_heap Sz Words Regs Dst
 
@@ -1262,15 +1188,13 @@ bs_init2 Fail Sz Words=u==0 Regs Flags Dst => \
 bs_init2 Fail Sz Words Regs Flags Dst => \
   i_bs_init_fail_heap Sz Words Fail Regs Dst
 
-i_bs_init_fail xy j I d
+i_bs_init_fail xy j? t? x
 
-i_bs_init_fail_heap s I j I d
+i_bs_init_fail_heap s I j? t? x
 
-i_bs_init I I d
-i_bs_init_heap_bin I I d
+i_bs_init W t? x
 
-i_bs_init_heap I I I d
-i_bs_init_heap_bin_heap I I I d
+i_bs_init_heap W I t? x
 
 
 bs_init_bits Fail Sz=o Words Regs Flags Dst => system_limit Fail
@@ -1283,16 +1207,16 @@ bs_init_bits Fail Sz Words=u==0 Regs Flags Dst => \
 bs_init_bits Fail Sz Words Regs Flags Dst => \
   i_bs_init_bits_fail_heap Sz Words Fail Regs Dst
 
-i_bs_init_bits_fail xy j I d
+i_bs_init_bits_fail xy j? t? x
 
-i_bs_init_bits_fail_heap s I j I d
+i_bs_init_bits_fail_heap s I j? t? x
 
-i_bs_init_bits I I d
-i_bs_init_bits_heap I I I d
+i_bs_init_bits W t? x
+i_bs_init_bits_heap W I t? x
 
 bs_add Fail S1=i==0 S2 Unit=u==1 D => move S2 D
 
-bs_add j s s I d
+bs_add j? s s t? x
 
 bs_append Fail Size Extra Live Unit Bin Flags Dst => \
   move Bin x | i_bs_append Fail Extra Live Unit Size Dst
@@ -1302,8 +1226,8 @@ bs_private_append Fail Size Unit Bin Flags Dst => \
 
 bs_init_writable
 
-i_bs_append j I I I s d
-i_bs_private_append j I s s d
+i_bs_append j? I t? t s x
+i_bs_private_append j? t s S x
 
 #
 # Storing integers into binaries.
@@ -1312,11 +1236,8 @@ i_bs_private_append j I s s d
 bs_put_integer Fail=j Sz=sq Unit=u Flags=u Src=s => \
 			gen_put_integer(Fail, Sz, Unit, Flags, Src)
 
-%macro: i_new_bs_put_integer NewBsPutInteger
-%macro: i_new_bs_put_integer_imm NewBsPutIntegerImm
-
-i_new_bs_put_integer j s I s
-i_new_bs_put_integer_imm j I I s
+i_new_bs_put_integer j? s t s
+i_new_bs_put_integer_imm j? W t s
 
 #
 # Utf8/utf16/utf32 support. (R12B-5)
@@ -1324,22 +1245,22 @@ i_new_bs_put_integer_imm j I I s
 
 bs_utf8_size j Src=s Dst=d => i_bs_utf8_size Src Dst
 
-i_bs_utf8_size s d
+i_bs_utf8_size s x
 
 bs_utf16_size j Src=s Dst=d => i_bs_utf16_size Src Dst
 
-i_bs_utf16_size s d
+i_bs_utf16_size s x
 
 bs_put_utf8 Fail u Src=s => i_bs_put_utf8 Fail Src
 
-i_bs_put_utf8 j s
+i_bs_put_utf8 j? s
 
-bs_put_utf16 j I s
+bs_put_utf16 j? t s
 
 bs_put_utf32 Fail=j Flags=u Src=s => \
    i_bs_validate_unicode Fail Src | bs_put_integer Fail i=32 u=1 Flags Src
 
-i_bs_validate_unicode j s
+i_bs_validate_unicode j? s
 
 #
 # Storing floats into binaries.
@@ -1349,11 +1270,8 @@ bs_put_float Fail Sz=q Unit Flags Val => badarg Fail
 bs_put_float Fail=j Sz=s Unit=u Flags=u Src=s => \
 			gen_put_float(Fail, Sz, Unit, Flags, Src)
 
-%macro: i_new_bs_put_float NewBsPutFloat
-%macro: i_new_bs_put_float_imm NewBsPutFloatImm
-
-i_new_bs_put_float j s I s
-i_new_bs_put_float_imm j I I s
+i_new_bs_put_float j? s t s
+i_new_bs_put_float_imm j? W t s
 
 #
 # Storing binaries into binaries.
@@ -1362,14 +1280,9 @@ i_new_bs_put_float_imm j I I s
 bs_put_binary Fail=j Sz=s Unit=u Flags=u Src=s => \
 			gen_put_binary(Fail, Sz, Unit, Flags, Src)
 
-%macro: i_new_bs_put_binary NewBsPutBinary
-i_new_bs_put_binary j s I s
-
-%macro: i_new_bs_put_binary_imm NewBsPutBinaryImm
-i_new_bs_put_binary_imm j I s
-
-%macro: i_new_bs_put_binary_all NewBsPutBinaryAll
-i_new_bs_put_binary_all j s I
+i_new_bs_put_binary j? s t s
+i_new_bs_put_binary_imm j? W s
+i_new_bs_put_binary_all j? s t
 
 #
 # Warning: The i_bs_put_string and i_new_bs_put_string instructions
@@ -1377,9 +1290,7 @@ i_new_bs_put_binary_all j s I
 # Don't change the instruction format unless you change the loader too.
 #
 
-bs_put_string I I
-
-%hot
+bs_put_string W W
 
 #
 # New floating point instructions (R8).
@@ -1393,11 +1304,13 @@ fnegate p FR1 FR2 => i_fnegate FR1 FR2
 
 fconv Arg=iqan Dst=l => move Arg x | fconv x Dst
 
-fmove q l
-fmove d l
-fmove l d
+fmove Arg=l Dst=d => fstore Arg Dst
+fmove Arg=dq Dst=l => fload Arg Dst
+
+fstore l d
+fload Sq l
 
-fconv d l
+fconv S l
 
 i_fadd l l l
 i_fsub l l l
@@ -1407,51 +1320,88 @@ i_fnegate l l
 
 fclearerror | no_fpe_signals() =>
 fcheckerror p | no_fpe_signals() =>
+
+%unless NO_FPE_SIGNALS
 fcheckerror p => i_fcheckerror
 
 i_fcheckerror
 fclearerror
+%endif
+
+%hot
 
 #
 # New apply instructions in R10B.
 #
 
-apply I
-apply_last I P
+apply t
+apply_last t Q
+
+#
+# Handle compatibility with OTP 17 here.
+#
+
+i_put_map_assoc/4
+
+# We KNOW that in OTP 20 (actually OTP 18 and higher), a put_map_assoc instruction
+# is always preceded by an is_map test. That means that put_map_assoc can never
+# fail and does not need any failure label.
+
+put_map_assoc Fail Map Dst Live Size Rest=* | compiled_with_otp_20_or_higher() => \
+	      i_put_map_assoc Map Dst Live Size Rest
+
+# Translate the put_map_assoc instruction if the module was compiled by a compiler
+# before 20. This is only necessary if the OTP 17 compiler was used, but we
+# have no safe and relatively easy way to know whether OTP 18/19 was used.
+
+put_map_assoc Fail=p Map Dst Live Size Rest=* => \
+	      ensure_map Map | i_put_map_assoc Map Dst Live Size Rest
+put_map_assoc Fail=f Map Dst Live Size Rest=* => \
+	      is_map Fail Map | i_put_map_assoc Map Dst Live Size Rest
+
+ensure_map Lit=q | literal_is_map(Lit) =>
+ensure_map Src=cqy => move Src x | ensure_map x
+
+%cold
+ensure_map x
+%hot
 
 #
-# Map instructions in R17.
+# Map instructions. First introduced in R17.
 #
 
-sorted_put_map_assoc/5
-put_map_assoc F Map Dst Live Size Rest=* | map_key_sort(Size, Rest) => \
-  sorted_put_map_assoc F Map Dst Live Size Rest
+sorted_put_map_assoc/4
+i_put_map_assoc Map Dst Live Size Rest=* | map_key_sort(Size, Rest) => \
+  sorted_put_map_assoc Map Dst Live Size Rest
 
 sorted_put_map_exact/5
 put_map_exact F Map Dst Live Size Rest=* | map_key_sort(Size, Rest) => \
   sorted_put_map_exact F Map Dst Live Size Rest
 
-sorted_put_map_assoc j Map Dst Live Size Rest=* | is_empty_map(Map) => \
+sorted_put_map_assoc Map Dst Live Size Rest=* | is_empty_map(Map) => \
    new_map Dst Live Size Rest
-sorted_put_map_assoc F Src=s Dst Live Size Rest=* => \
-	       update_map_assoc F Src Dst Live Size Rest
-sorted_put_map_assoc F Src Dst Live Size Rest=* => \
-	       move Src x | update_map_assoc F x Dst Live Size Rest
+sorted_put_map_assoc Src=s Dst Live Size Rest=* => \
+	       update_map_assoc Src Dst Live Size Rest
+sorted_put_map_assoc Src Dst Live Size Rest=* => \
+	       move Src x | update_map_assoc x Dst Live Size Rest
 
 sorted_put_map_exact F Src=s Dst Live Size Rest=* => \
 	      update_map_exact F Src Dst Live Size Rest
 sorted_put_map_exact F Src Dst Live Size Rest=* => \
 	      move Src x | update_map_exact F x Dst Live Size Rest
 
-new_map d I I
-update_map_assoc j s d I I
-update_map_exact j s d I I
+new_map Dst Live Size Rest=* | is_small_map_literal_keys(Size, Rest) => \
+   gen_new_small_map_lit(Dst, Live, Size, Rest)
+
+new_map d t I
+i_new_small_map_lit d t q
+update_map_assoc s d t I
+update_map_exact j? s d t I
 
 is_map Fail Lit=q | literal_is_map(Lit) =>
 is_map Fail cq => jump Fail
 
-%macro: is_map IsMap -fail_action
-is_map f xy
+is_map f? xy
 
 ## Transform has_map_fields #{ K1 := _, K2 := _ } to has_map_elements
 
@@ -1465,16 +1415,14 @@ get_map_elements Fail Src=xy Size=u==2 Rest=* => \
 get_map_elements Fail Src Size Rest=* | map_key_sort(Size, Rest) => \
    gen_get_map_elements(Fail, Src, Size, Rest)
 
-i_get_map_elements f s I
+i_get_map_elements f? s I
 
 i_get_map_element Fail Src=xy Key=y Dst => \
     move Key x | i_get_map_element Fail Src x Dst
 
-%macro: i_get_map_element_hash GetMapElementHash -fail_action
-i_get_map_element_hash f xy c I xy
+i_get_map_element_hash f? xy c I xy
 
-%macro: i_get_map_element GetMapElement -fail_action
-i_get_map_element f xy x xy
+i_get_map_element f? xy x xy
 
 #
 # Convert the plus operations to a generic plus instruction.
@@ -1509,9 +1457,9 @@ gen_minus p Live Reg=d Int=i Dst | negation_is_small(Int) => \
 # GCing arithmetic instructions.
 #
 
-gen_plus Fail Live S1 S2 Dst => i_plus Fail Live S1 S2 Dst
+gen_plus Fail Live S1 S2 Dst => i_plus S1 S2 Fail Live Dst
 
-gen_minus Fail Live S1 S2 Dst => i_minus Fail Live S1 S2 Dst
+gen_minus Fail Live S1 S2 Dst => i_minus S1 S2 Fail Live Dst
 
 gc_bif2 Fail Live u$bif:erlang:stimes/2 S1 S2 Dst => \
   i_times Fail Live S1 S2 Dst
@@ -1522,15 +1470,15 @@ gc_bif2 Fail Live u$bif:erlang:intdiv/2 S1 S2 Dst => \
   i_int_div Fail Live S1 S2 Dst
 
 gc_bif2 Fail Live u$bif:erlang:rem/2 S1 S2 Dst => \
-  i_rem Fail Live S1 S2 Dst
+  i_rem S1 S2 Fail Live Dst
 
 gc_bif2 Fail Live u$bif:erlang:bsl/2 S1 S2 Dst => \
-  i_bsl Fail Live S1 S2 Dst
+  i_bsl S1 S2 Fail Live Dst
 gc_bif2 Fail Live u$bif:erlang:bsr/2 S1 S2 Dst => \
-  i_bsr Fail Live S1 S2 Dst
+  i_bsr S1 S2 Fail Live Dst
 
 gc_bif2 Fail Live u$bif:erlang:band/2 S1 S2 Dst => \
-  i_band Fail Live S1 S2 Dst
+  i_band S1 S2 Fail Live Dst
 
 gc_bif2 Fail Live u$bif:erlang:bor/2 S1 S2 Dst => \
   i_bor Fail Live S1 S2 Dst
@@ -1540,32 +1488,34 @@ gc_bif2 Fail Live u$bif:erlang:bxor/2 S1 S2 Dst => \
 
 gc_bif1 Fail I u$bif:erlang:bnot/1 Src Dst=d => i_int_bnot Fail Src I Dst
 
-i_increment rxy I I d
+i_increment rxy W t d
+
+i_plus x xy j? t d
+i_plus s s  j? t d
 
-i_plus j I x xy d
-i_plus j I s s d
+i_minus x x j? t d
+i_minus s s j? t d
 
-i_minus j I x x d
-i_minus j I s s d
+i_times j? t s s d
 
-i_times j I s s d
+i_m_div j? t s s d
+i_int_div j? t s s d
 
-i_m_div j I s s d
-i_int_div j I s s d
+i_rem x x j? t d
+i_rem s s j? t d
 
-i_rem j I x x d
-i_rem j I s s d
+i_bsl s s j? t d
+i_bsr s s j? t d
 
-i_bsl j I s s d
-i_bsr j I s s d
+i_band x c j? t d
+i_band s s j? t d
 
-i_band j I x c d
-i_band j I s s d
+i_bor j? I s s d
+i_bxor j? I s s d
 
-i_bor j I s s d
-i_bxor j I s s d
+i_int_bnot Fail Src=c Live Dst => move Src x | i_int_bnot Fail x Live Dst
 
-i_int_bnot j s I d
+i_int_bnot j? S t d
 
 #
 # Old guard BIFs that creates heap fragments are no longer allowed.
@@ -1589,9 +1539,9 @@ gc_bif2 Fail I Bif S1 S2 Dst => \
 gc_bif3 Fail I Bif S1 S2 S3 Dst => \
 	gen_guard_bif3(Fail, I, Bif, S1, S2, S3, Dst)
 
-i_gc_bif1 j I s I d
+i_gc_bif1 j? W s t? d
 
-i_gc_bif2 j I I s s d
+i_gc_bif2 j? W t? s s d
 
 ii_gc_bif3/7
 
@@ -1600,7 +1550,7 @@ ii_gc_bif3/7
 ii_gc_bif3 Fail Bif Live S1 S2 S3 Dst => \
   move S1 x | i_gc_bif3 Fail Bif Live S2 S3 Dst
 
-i_gc_bif3 j I I s s d
+i_gc_bif3 j? W t? s s d
 
 #
 # The following instruction is specially handled in beam_load.c
@@ -1618,8 +1568,19 @@ on_load
 #
 # R14A.
 #
-recv_mark f
+# Modified in OTP 21 because it turns out that we don't need the
+# label after all.
+#
+
+recv_mark f => i_recv_mark
+i_recv_mark
 
 recv_set Fail | label Lbl | loop_rec Lf Reg => \
    i_recv_set | label Lbl | loop_rec Lf Reg
 i_recv_set
+
+#
+# OTP 21.
+#
+
+build_stacktrace
diff --git a/erts/emulator/beam/register.c b/erts/emulator/beam/register.c
index bf3267cff1..92a0854ad3 100644
--- a/erts/emulator/beam/register.c
+++ b/erts/emulator/beam/register.c
@@ -38,16 +38,15 @@ static Hash process_reg;
 
 #define REG_HASH(term) ((HashValue) atom_val(term))
 
-static erts_smp_rwmtx_t regtab_rwmtx;
+static erts_rwmtx_t regtab_rwmtx;
 
-#define reg_try_read_lock()		erts_smp_rwmtx_tryrlock(&regtab_rwmtx)
-#define reg_try_write_lock()		erts_smp_rwmtx_tryrwlock(&regtab_rwmtx)
-#define reg_read_lock()			erts_smp_rwmtx_rlock(&regtab_rwmtx)
-#define reg_write_lock()		erts_smp_rwmtx_rwlock(&regtab_rwmtx)
-#define reg_read_unlock()		erts_smp_rwmtx_runlock(&regtab_rwmtx)
-#define reg_write_unlock()		erts_smp_rwmtx_rwunlock(&regtab_rwmtx)
+#define reg_try_read_lock()		erts_rwmtx_tryrlock(&regtab_rwmtx)
+#define reg_try_write_lock()		erts_rwmtx_tryrwlock(&regtab_rwmtx)
+#define reg_read_lock()			erts_rwmtx_rlock(&regtab_rwmtx)
+#define reg_write_lock()		erts_rwmtx_rwlock(&regtab_rwmtx)
+#define reg_read_unlock()		erts_rwmtx_runlock(&regtab_rwmtx)
+#define reg_write_unlock()		erts_rwmtx_rwunlock(&regtab_rwmtx)
 
-#ifdef ERTS_SMP
 static ERTS_INLINE void
 reg_safe_read_lock(Process *c_p, ErtsProcLocks *c_p_locks)
 {
@@ -64,7 +63,7 @@ reg_safe_read_lock(Process *c_p, ErtsProcLocks *c_p_locks)
 	}
 
 	/* Release process locks in order to avoid deadlock */
-	erts_smp_proc_unlock(c_p, *c_p_locks);
+	erts_proc_unlock(c_p, *c_p_locks);
 	*c_p_locks = 0;
     }
 
@@ -87,14 +86,13 @@ reg_safe_write_lock(Process *c_p, ErtsProcLocks *c_p_locks)
 	}
 
 	/* Release process locks in order to avoid deadlock */
-	erts_smp_proc_unlock(c_p, *c_p_locks);
+	erts_proc_unlock(c_p, *c_p_locks);
 	*c_p_locks = 0;
     }
 
     reg_write_lock();
 }
 
-#endif
 
 static ERTS_INLINE int
 is_proc_alive(Process *p)
@@ -141,11 +139,11 @@ static void reg_free(RegProc *obj)
 void init_register_table(void)
 {
     HashFunctions f;
-    erts_smp_rwmtx_opt_t rwmtx_opt = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
-    rwmtx_opt.type = ERTS_SMP_RWMTX_TYPE_FREQUENT_READ;
-    rwmtx_opt.lived = ERTS_SMP_RWMTX_LONG_LIVED;
+    erts_rwmtx_opt_t rwmtx_opt = ERTS_RWMTX_OPT_DEFAULT_INITER;
+    rwmtx_opt.type = ERTS_RWMTX_TYPE_FREQUENT_READ;
+    rwmtx_opt.lived = ERTS_RWMTX_LONG_LIVED;
 
-    erts_smp_rwmtx_init_opt(&regtab_rwmtx, &rwmtx_opt, "reg_tab", NIL,
+    erts_rwmtx_init_opt(&regtab_rwmtx, &rwmtx_opt, "reg_tab", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
 
     f.hash = (H_FUN) reg_hash;
@@ -175,7 +173,7 @@ int erts_register_name(Process *c_p, Eterm name, Eterm id)
     Process *proc = NULL;
     Port *port = NULL;
     RegProc r, *rp;
-    ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(c_p);
+    ERTS_CHK_HAVE_ONLY_MAIN_PROC_LOCK(c_p);
 
     if (is_not_atom(name) || name == am_undefined)
 	return res;
@@ -185,7 +183,7 @@ int erts_register_name(Process *c_p, Eterm name, Eterm id)
     else {
 	if (is_not_internal_pid(id) && is_not_internal_port(id))
 	    return res;
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
 	if (is_internal_port(id)) {
 	    port = erts_id2port(id);
 	    if (!port)
@@ -193,15 +191,13 @@ int erts_register_name(Process *c_p, Eterm name, Eterm id)
 	}
     }
 
-#ifdef ERTS_SMP
     {
 	ErtsProcLocks proc_locks = proc ? ERTS_PROC_LOCK_MAIN : 0;
 	reg_safe_write_lock(proc, &proc_locks);
 
 	if (proc && !proc_locks)
-	    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+	    erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
     }
-#endif
 
     if (is_internal_pid(id)) {
 	if (!proc)
@@ -215,7 +211,7 @@ int erts_register_name(Process *c_p, Eterm name, Eterm id)
     }
     else {
 	ASSERT(!INVALID_PORT(port, id));
-	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(port));
+	ERTS_LC_ASSERT(erts_lc_is_port_locked(port));
 	r.pt = port;
 	if (r.pt->common.u.alive.reg)
 	    goto done;
@@ -250,8 +246,8 @@ int erts_register_name(Process *c_p, Eterm name, Eterm id)
 	erts_port_release(port);
     if (c_p != proc) {
 	if (proc)
-	    erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+	    erts_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
+	erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
     }
     return res;
 }
@@ -272,17 +268,15 @@ erts_whereis_name_to_id(Process *c_p, Eterm name)
     HashValue hval;
     int ix;
     HashBucket* b;
-#ifdef ERTS_SMP
     ErtsProcLocks c_p_locks = 0;
     if (c_p) {
         c_p_locks = ERTS_PROC_LOCK_MAIN;
-        ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(c_p);
+        ERTS_CHK_HAVE_ONLY_MAIN_PROC_LOCK(c_p);
     }
     reg_safe_read_lock(c_p, &c_p_locks);
 
     if (c_p && !c_p_locks)
-        erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
-#endif
+        erts_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
 
     hval = REG_HASH(name);
     ix = hval % process_reg.size;
@@ -331,7 +325,6 @@ erts_whereis_name(Process *c_p,
     HashValue hval;
     int ix;
     HashBucket* b;
-#ifdef ERTS_SMP
     ErtsProcLocks current_c_p_locks;
     Port *pending_port = NULL;
 
@@ -348,7 +341,6 @@ erts_whereis_name(Process *c_p,
      * - read reg lock
      * - current_c_p_locks (either c_p_locks or 0) on c_p
      */
-#endif
 
     hval = REG_HASH(name);
     ix = hval % process_reg.size;
@@ -370,7 +362,6 @@ erts_whereis_name(Process *c_p,
 	if (!rp)
 	    *proc = NULL;
 	else {
-#ifdef ERTS_SMP
 	    if (!rp->p)
 		*proc = NULL;
 	    else {
@@ -387,17 +378,10 @@ erts_whereis_name(Process *c_p,
 		    *proc = rp->p;
 		else {
 		    if (need_locks)
-			erts_smp_proc_unlock(rp->p, need_locks);
+			erts_proc_unlock(rp->p, need_locks);
 		    *proc = NULL;
 		}
 	    }
-#else
-	    if (rp->p
-		&& ((flags & ERTS_P2P_FLG_ALLOW_OTHER_X) || is_proc_alive(rp->p)))
-		*proc = rp->p;
-	    else
-		*proc = NULL;
-#endif
 	    if (*proc && (flags & ERTS_P2P_FLG_INC_REFC))
 		erts_proc_inc_refc(*proc);
 	}
@@ -407,7 +391,6 @@ erts_whereis_name(Process *c_p,
 	if (!rp || !rp->pt)
 	    *port = NULL;
 	else {
-#ifdef ERTS_SMP
             if (lock_port) {
                 if (pending_port == rp->pt)
                     pending_port = NULL;
@@ -419,11 +402,11 @@ erts_whereis_name(Process *c_p,
                         pending_port = NULL;
                     }
 		    
-                    if (erts_smp_port_trylock(rp->pt) == EBUSY) {
+                    if (erts_port_trylock(rp->pt) == EBUSY) {
                         Eterm id = rp->pt->common.id; /* id read only... */
                         /* Unlock all locks, acquire port lock, and restart... */
                         if (current_c_p_locks) {
-                            erts_smp_proc_unlock(c_p, current_c_p_locks);
+                            erts_proc_unlock(c_p, current_c_p_locks);
                             current_c_p_locks = 0;
                         }
                         reg_read_unlock();
@@ -431,19 +414,16 @@ erts_whereis_name(Process *c_p,
                         goto restart;
                     }
                 }
-                ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(rp->pt));
+                ERTS_LC_ASSERT(erts_lc_is_port_locked(rp->pt));
             }
-#endif
 	    *port = rp->pt;
 	}
     }
 
-#ifdef ERTS_SMP
     if (c_p && !current_c_p_locks)
-	erts_smp_proc_lock(c_p, c_p_locks);
+	erts_proc_lock(c_p, c_p_locks);
     if (pending_port)
 	erts_port_release(pending_port);
-#endif
 
     reg_read_unlock();
 }
@@ -476,7 +456,6 @@ int erts_unregister_name(Process *c_p,
     RegProc r, *rp;
     Port *port = c_prt;
     ErtsProcLocks current_c_p_locks = 0;
-#ifdef ERTS_SMP
 
     /*
      * SMP note: If 'c_prt != NULL' and 'c_prt->reg->name == name',
@@ -492,18 +471,15 @@ int erts_unregister_name(Process *c_p,
  restart:
 
     reg_safe_write_lock(c_p, &current_c_p_locks);
-#endif
 
     r.name = name;
     if (is_non_value(name)) {
 	/* Unregister current process name */
 	ASSERT(c_p);
-#ifdef ERTS_SMP
 	if (current_c_p_locks != c_p_locks) {
-	    erts_smp_proc_lock(c_p, c_p_locks);
+	    erts_proc_lock(c_p, c_p_locks);
 	    current_c_p_locks = c_p_locks;
 	}
-#endif
 	if (c_p->common.u.alive.reg) {
 	    r.name = c_p->common.u.alive.reg->name;
 	} else {
@@ -516,36 +492,34 @@ int erts_unregister_name(Process *c_p,
     if ((rp = (RegProc*) hash_get(&process_reg, (void*) &r)) != NULL) {
 	if (rp->pt) {
 	    if (port != rp->pt) {
-#ifdef ERTS_SMP
 		if (port) {
 		    ASSERT(port != c_prt);
 		    erts_port_release(port);
 		    port = NULL;
 		}
 
-		if (erts_smp_port_trylock(rp->pt) == EBUSY) {
+		if (erts_port_trylock(rp->pt) == EBUSY) {
 		    Eterm id = rp->pt->common.id; /* id read only... */
 		    /* Unlock all locks, acquire port lock, and restart... */
 		    if (current_c_p_locks) {
-			erts_smp_proc_unlock(c_p, current_c_p_locks);
+			erts_proc_unlock(c_p, current_c_p_locks);
 			current_c_p_locks = 0;
 		    }
 		    reg_write_unlock();
 		    port = erts_id2port(id);
 		    goto restart;
 		}
-#endif
 		port = rp->pt;
 	    }
 
 	    ASSERT(rp->pt == port);
-	    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(port));
+	    ERTS_LC_ASSERT(erts_lc_is_port_locked(port));
 
 	    rp->pt->common.u.alive.reg = NULL;
 
 	    if (IS_TRACED_FL(port, F_TRACE_PORTS)) {
                 if (current_c_p_locks) {
-                    erts_smp_proc_unlock(c_p, current_c_p_locks);
+                    erts_proc_unlock(c_p, current_c_p_locks);
                     current_c_p_locks = 0;
                 }
 		trace_port(port, am_unregister, r.name);
@@ -553,7 +527,6 @@ int erts_unregister_name(Process *c_p,
 
 	} else if (rp->p) {
 
-#ifdef ERTS_SMP
 	    erts_proc_safelock(c_p,
 			       current_c_p_locks,
 			       c_p_locks,
@@ -561,17 +534,14 @@ int erts_unregister_name(Process *c_p,
 			       (c_p == rp->p) ?  current_c_p_locks : 0,
 			       ERTS_PROC_LOCK_MAIN);
 	    current_c_p_locks = c_p_locks;
-#endif
 	    rp->p->common.u.alive.reg = NULL;
 	    if (IS_TRACED_FL(rp->p, F_TRACE_PROCS)) {
                 trace_proc(rp->p, (c_p == rp->p) ? c_p_locks : ERTS_PROC_LOCK_MAIN,
                            rp->p, am_unregister, r.name);
 	    }
-#ifdef ERTS_SMP
 	    if (rp->p != c_p) {
-		erts_smp_proc_unlock(rp->p, ERTS_PROC_LOCK_MAIN);
+		erts_proc_unlock(rp->p, ERTS_PROC_LOCK_MAIN);
 	    }
-#endif
 	}
 	hash_erase(&process_reg, (void*) &r);
 	res = 1;
@@ -585,14 +555,12 @@ int erts_unregister_name(Process *c_p,
 	    erts_port_release(port);
 	}
 	if (c_prt) {
-	    erts_smp_port_lock(c_prt);
+	    erts_port_lock(c_prt);
 	}
     }
-#ifdef ERTS_SMP
     if (c_p && !current_c_p_locks) {
-	erts_smp_proc_lock(c_p, c_p_locks);
+	erts_proc_lock(c_p, c_p_locks);
     }
-#endif
     return res;
 }
 
@@ -633,14 +601,12 @@ BIF_RETTYPE registered_0(BIF_ALIST_0)
     Uint need;
     Eterm* hp;
     HashBucket **bucket;
-#ifdef ERTS_SMP
     ErtsProcLocks proc_locks = ERTS_PROC_LOCK_MAIN;
 
-    ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(BIF_P);
+    ERTS_CHK_HAVE_ONLY_MAIN_PROC_LOCK(BIF_P);
     reg_safe_read_lock(BIF_P, &proc_locks);
     if (!proc_locks)
-	erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
-#endif
+	erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 
     bucket = process_reg.bucket;
 
diff --git a/erts/emulator/beam/safe_hash.c b/erts/emulator/beam/safe_hash.c
index 527c9efeca..73306030ae 100644
--- a/erts/emulator/beam/safe_hash.c
+++ b/erts/emulator/beam/safe_hash.c
@@ -62,7 +62,7 @@ static ERTS_INLINE int align_up_pow2(int val)
 */
 static void rehash(SafeHash* h, int grow_limit)
 {
-    if (erts_smp_atomic_xchg_acqb(&h->is_rehashing, 1) != 0) {        
+    if (erts_atomic_xchg_acqb(&h->is_rehashing, 1) != 0) {
 	return; /* already in progress */
     }
     if (h->grow_limit == grow_limit) {
@@ -77,7 +77,7 @@ static void rehash(SafeHash* h, int grow_limit)
 	sys_memzero(new_tab, bytes);
 
 	for (i=0; i<SAFE_HASH_LOCK_CNT; i++) { /* stop all traffic */
-	    erts_smp_mtx_lock(&h->lock_vec[i].mtx);
+	    erts_mtx_lock(&h->lock_vec[i].mtx);
 	}
 
 	h->tab = new_tab;
@@ -95,12 +95,12 @@ static void rehash(SafeHash* h, int grow_limit)
 	}
 
 	for (i=0; i<SAFE_HASH_LOCK_CNT; i++) {
-	    erts_smp_mtx_unlock(&h->lock_vec[i].mtx);
+	    erts_mtx_unlock(&h->lock_vec[i].mtx);
 	}
 	erts_free(h->type, (void *) old_tab);
     }
     /*else already done */
-    erts_smp_atomic_set_relb(&h->is_rehashing, 0);
+    erts_atomic_set_relb(&h->is_rehashing, 0);
 }
 
 
@@ -115,7 +115,7 @@ void safe_hash_get_info(SafeHashInfo *hi, SafeHash *h)
     int objects = 0;
 
     for (lock_ix=0; lock_ix<SAFE_HASH_LOCK_CNT; lock_ix++) {
-	erts_smp_mtx_lock(&h->lock_vec[lock_ix].mtx); 
+	erts_mtx_lock(&h->lock_vec[lock_ix].mtx);
 	size = h->size_mask + 1;
 	for (i = lock_ix; i < size; i += SAFE_HASH_LOCK_CNT) {
 	    int depth = 0;
@@ -128,7 +128,7 @@ void safe_hash_get_info(SafeHashInfo *hi, SafeHash *h)
 	    if (depth > max_depth)
 		max_depth = depth;
 	}
-	erts_smp_mtx_unlock(&h->lock_vec[lock_ix].mtx);	
+	erts_mtx_unlock(&h->lock_vec[lock_ix].mtx);
     }
 
     hi->name  = h->name;
@@ -145,9 +145,9 @@ int safe_hash_table_sz(SafeHash *h)
   int i, size;
   for(i=0; h->name[i]; i++);
   i++;
-  erts_smp_mtx_lock(&h->lock_vec[0].mtx); /* any lock will do to read size */
+  erts_mtx_lock(&h->lock_vec[0].mtx); /* any lock will do to read size */
   size = h->size_mask + 1;
-  erts_smp_mtx_unlock(&h->lock_vec[0].mtx);
+  erts_mtx_unlock(&h->lock_vec[0].mtx);
   return sizeof(SafeHash) + size*sizeof(SafeHashBucket*) + i;
 }
 
@@ -168,10 +168,10 @@ SafeHash* safe_hash_init(ErtsAlcType_t type, SafeHash* h, char* name, erts_lock_
     h->name = name;
     h->fun = fun;
     set_size(h,size);
-    erts_smp_atomic_init_nob(&h->is_rehashing, 0);
-    erts_smp_atomic_init_nob(&h->nitems, 0);
+    erts_atomic_init_nob(&h->is_rehashing, 0);
+    erts_atomic_init_nob(&h->nitems, 0);
     for (i=0; i<SAFE_HASH_LOCK_CNT; i++) {
-        erts_smp_mtx_init(&h->lock_vec[i].mtx, "safe_hash", NIL,
+        erts_mtx_init(&h->lock_vec[i].mtx, "safe_hash", NIL,
             flags);
     }
     return h;
@@ -185,8 +185,8 @@ void* safe_hash_get(SafeHash* h, void* tmpl)
 {
     SafeHashValue hval = h->fun.hash(tmpl);
     SafeHashBucket* b;
-    erts_smp_mtx_t* lock = &h->lock_vec[hval % SAFE_HASH_LOCK_CNT].mtx;
-    erts_smp_mtx_lock(lock);
+    erts_mtx_t* lock = &h->lock_vec[hval % SAFE_HASH_LOCK_CNT].mtx;
+    erts_mtx_lock(lock);
     b = h->tab[hval & h->size_mask];
 	
     while(b != NULL) {
@@ -194,7 +194,7 @@ void* safe_hash_get(SafeHash* h, void* tmpl)
 	    break;
 	b = b->next;
     }
-    erts_smp_mtx_unlock(lock);
+    erts_mtx_unlock(lock);
     return (void*) b;
 }
 
@@ -207,13 +207,13 @@ void* safe_hash_put(SafeHash* h, void* tmpl)
     SafeHashValue hval = h->fun.hash(tmpl);
     SafeHashBucket* b;
     SafeHashBucket** head;
-    erts_smp_mtx_t* lock = &h->lock_vec[hval % SAFE_HASH_LOCK_CNT].mtx;
-    erts_smp_mtx_lock(lock);
+    erts_mtx_t* lock = &h->lock_vec[hval % SAFE_HASH_LOCK_CNT].mtx;
+    erts_mtx_lock(lock);
     head = &h->tab[hval & h->size_mask];
     b = *head;
     while(b != NULL) {
 	if ((b->hvalue == hval) && (h->fun.cmp(tmpl, (void*)b) == 0)) {
-	    erts_smp_mtx_unlock(lock);
+	    erts_mtx_unlock(lock);
 	    return b;
 	}
 	b = b->next;
@@ -224,8 +224,8 @@ void* safe_hash_put(SafeHash* h, void* tmpl)
     b->next = *head;
     *head = b;
     grow_limit = h->grow_limit;
-    erts_smp_mtx_unlock(lock);
-    if (erts_smp_atomic_inc_read_nob(&h->nitems) > grow_limit) {
+    erts_mtx_unlock(lock);
+    if (erts_atomic_inc_read_nob(&h->nitems) > grow_limit) {
 	rehash(h, grow_limit);
     }
     return (void*) b;
@@ -240,36 +240,37 @@ void* safe_hash_erase(SafeHash* h, void* tmpl)
     SafeHashValue hval = h->fun.hash(tmpl);
     SafeHashBucket* b;
     SafeHashBucket** prevp;
-    erts_smp_mtx_t* lock = &h->lock_vec[hval % SAFE_HASH_LOCK_CNT].mtx;
-    erts_smp_mtx_lock(lock);
+    erts_mtx_t* lock = &h->lock_vec[hval % SAFE_HASH_LOCK_CNT].mtx;
+    erts_mtx_lock(lock);
     prevp = &h->tab[hval & h->size_mask];
     b = *prevp;
     while(b != NULL) {
 	if ((b->hvalue == hval) && (h->fun.cmp(tmpl, (void*)b) == 0)) {
 	    *prevp = b->next;
-	    erts_smp_mtx_unlock(lock);
-	    erts_smp_atomic_dec_nob(&h->nitems);
+	    erts_mtx_unlock(lock);
+	    erts_atomic_dec_nob(&h->nitems);
 	    h->fun.free((void*)b);
 	    return tmpl;
 	}
 	prevp = &b->next;
 	b = b->next;
     }
-    erts_smp_mtx_unlock(lock);
+    erts_mtx_unlock(lock);
     return NULL;
 }
 
 /*
-** Call 'func(obj,func_arg2)' for all objects in table. NOT SAFE!!!
+** Call 'func(obj,func_arg2,func_arg3)' for all objects in table. NOT SAFE!!!
 */
-void safe_hash_for_each(SafeHash* h, void (*func)(void *, void *), void *func_arg2)
+void safe_hash_for_each(SafeHash* h, void (*func)(void *, void *, void *),
+                        void *func_arg2, void *func_arg3)
 {
     int i;
 
     for (i = 0; i <= h->size_mask; i++) {
 	SafeHashBucket* b = h->tab[i];
 	while (b != NULL) {
-	    (*func)((void *) b, func_arg2);
+	    (*func)((void *) b, func_arg2, func_arg3);
 	    b = b->next;
 	}
     }
@@ -280,7 +281,7 @@ void erts_lcnt_enable_hash_lock_count(SafeHash *h, erts_lock_flags_t flags, int
     int i;
 
     for(i = 0; i < SAFE_HASH_LOCK_CNT; i++) {
-        erts_smp_mtx_t *lock = &h->lock_vec[i].mtx;
+        erts_mtx_t *lock = &h->lock_vec[i].mtx;
 
         if(enable) {
             erts_lcnt_install_new_lock_info(&lock->lcnt, "safe_hash", NIL,
diff --git a/erts/emulator/beam/safe_hash.h b/erts/emulator/beam/safe_hash.h
index dde48a6de8..af97b4cb4d 100644
--- a/erts/emulator/beam/safe_hash.h
+++ b/erts/emulator/beam/safe_hash.h
@@ -73,11 +73,11 @@ typedef struct
     int size_mask;	      /* (RW) Number of slots - 1 */
     SafeHashBucket** tab;     /* (RW) Vector of bucket pointers (objects) */
     int grow_limit;           /* (RW) Threshold for growing table */
-    erts_smp_atomic_t nitems;       /* (A) Number of items in table */
-    erts_smp_atomic_t is_rehashing; /* (A) Table rehashing in progress */
+    erts_atomic_t nitems;       /* (A) Number of items in table */
+    erts_atomic_t is_rehashing; /* (A) Table rehashing in progress */
 
     union {
-	erts_smp_mtx_t mtx;
+	erts_mtx_t mtx;
 	byte __cache_line__[64];
     }lock_vec[SAFE_HASH_LOCK_CNT];
 
@@ -95,7 +95,7 @@ void* safe_hash_get(SafeHash*, void*);
 void* safe_hash_put(SafeHash*, void*);
 void* safe_hash_erase(SafeHash*, void*);
 
-void  safe_hash_for_each(SafeHash*, void (*func)(void *, void *), void *);
+void  safe_hash_for_each(SafeHash*, void (*func)(void *, void *, void *), void *, void *);
 
 #ifdef ERTS_ENABLE_LOCK_COUNT
 void erts_lcnt_enable_hash_lock_count(SafeHash*, erts_lock_flags_t, int);
diff --git a/erts/emulator/beam/select_instrs.tab b/erts/emulator/beam/select_instrs.tab
new file mode 100644
index 0000000000..2951949d38
--- /dev/null
+++ b/erts/emulator/beam/select_instrs.tab
@@ -0,0 +1,190 @@
+// -*- c -*-
+//
+// %CopyrightBegin%
+//
+// Copyright Ericsson AB 2017. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// %CopyrightEnd%
+//
+
+i_select_val_bins := select_val_bins.fetch.select;
+
+select_val_bins.head() {
+    Eterm select_val;
+}
+
+select_val_bins.fetch(Src) {
+    select_val = $Src;
+}
+
+select_val_bins.select(Fail, NumElements) {
+    struct Singleton {
+        BeamInstr val;
+    };
+    struct Singleton* low;
+    struct Singleton* high;
+    struct Singleton* mid;
+    int bdiff; /* int not long because the arrays aren't that large */
+
+    low = (struct Singleton *) ($NEXT_INSTRUCTION);
+    high = low + $NumElements;
+
+    /* The pointer subtraction (high-low) below must produce
+     * a signed result, because high could be < low. That
+     * requires the compiler to insert quite a bit of code.
+     *
+     * However, high will be > low so the result will be
+     * positive. We can use that knowledge to optimise the
+     * entire sequence, from the initial comparison to the
+     * computation of mid.
+     *
+     * -- Mikael Pettersson, Acumem AB
+     *
+     * Original loop control code:
+     *
+     * while (low < high) {
+     *    mid = low + (high-low) / 2;
+     *
+     */
+    while ((bdiff = (int)((char*)high - (char*)low)) > 0) {
+        unsigned int boffset = ((unsigned int)bdiff >> 1) & ~(sizeof(struct Singleton)-1);
+
+        mid = (struct Singleton*)((char*)low + boffset);
+        if (select_val < mid->val) {
+            high = mid;
+        } else if (select_val > mid->val) {
+            low = mid + 1;
+        } else {
+            Sint32* jump_tab = (Sint32 *) ($NEXT_INSTRUCTION + $NumElements);
+            Sint32 offset = jump_tab[mid - (struct Singleton *)($NEXT_INSTRUCTION)];
+            $JUMP(offset);
+        }
+    }
+    $JUMP($Fail);
+}
+
+i_select_tuple_arity2 := select_val2.src.get_arity.execute;
+i_select_val2 := select_val2.src.execute;
+
+select_val2.head() {
+    Eterm select_val2;
+}
+
+select_val2.src(Src) {
+    select_val2 = $Src;
+}
+
+select_val2.get_arity() {
+    if (ERTS_LIKELY(is_tuple(select_val2))) {
+        select_val2 = *tuple_val(select_val2);
+    } else {
+        select_val2 = NIL;
+    }
+}
+
+select_val2.execute(Fail, T1, T2) {
+    Sint32* jump_tab = (Sint32 *) ($NEXT_INSTRUCTION);
+
+    if (select_val2 == $T1) {
+        $JUMP(jump_tab[0]);
+    } else if (select_val2 == $T2) {
+        $JUMP(jump_tab[1]);
+    } else {
+        $FAIL($Fail);
+    }
+}
+
+i_select_tuple_arity := select_val_lin.fetch.get_arity.execute;
+i_select_val_lins := select_val_lin.fetch.execute;
+
+select_val_lin.head() {
+    Eterm select_val;
+}
+
+select_val_lin.fetch(Src) {
+    select_val = $Src;
+}
+
+select_val_lin.get_arity() {
+    if (ERTS_LIKELY(is_tuple(select_val))) {
+        select_val = *tuple_val(select_val);
+    } else {
+        select_val = NIL;
+    }
+}
+
+select_val_lin.execute(Fail, N) {
+    BeamInstr* vs = $NEXT_INSTRUCTION;
+    int ix = 0;
+
+    for (;;) {
+        if (vs[ix+0] >= select_val) {
+            ix += 0;
+            break;
+        }
+        if (vs[ix+1] >= select_val) {
+            ix += 1;
+            break;
+        }
+        ix += 2;
+    }
+
+    if (vs[ix] == select_val) {
+        Sint32* jump_tab = (Sint32 *) ($NEXT_INSTRUCTION + $N);
+        Eterm offset = jump_tab[ix];
+        $JUMP(offset);
+    } else {
+        $JUMP($Fail);
+    }
+}
+
+JUMP_ON_VAL(Fail, Index, N, Base) {
+    if (is_small($Index)) {
+        $Index = (Uint) (signed_val($Index) - $Base);
+        if ($Index < $N) {
+            Sint32* jump_tab = (Sint32 *) ($NEXT_INSTRUCTION);
+            $JUMP(jump_tab[$Index]);
+        }
+    }
+    $FAIL($Fail);
+}
+
+i_jump_on_val_zero := jump_on_val_zero.fetch.execute;
+
+jump_on_val_zero.head() {
+    Eterm index;
+}
+
+jump_on_val_zero.fetch(Src) {
+    index = $Src;
+}
+
+jump_on_val_zero.execute(Fail, N) {
+    $JUMP_ON_VAL($Fail, index, $N, 0);
+}
+
+i_jump_on_val := jump_on_val.fetch.execute;
+
+jump_on_val.head() {
+    Eterm index;
+}
+
+jump_on_val.fetch(Src) {
+    index = $Src;
+}
+
+jump_on_val.execute(Fail, N, Base) {
+    $JUMP_ON_VAL($Fail, index, $N, $Base);
+}
diff --git a/erts/emulator/beam/sys.h b/erts/emulator/beam/sys.h
index 704d567337..bf7d310568 100644
--- a/erts/emulator/beam/sys.h
+++ b/erts/emulator/beam/sys.h
@@ -21,7 +21,7 @@
 #ifndef __SYS_H__
 #define __SYS_H__
 
-#if !defined(__GNUC__)
+#if !defined(__GNUC__) || defined(__e2k__)
 #  define ERTS_AT_LEAST_GCC_VSN__(MAJ, MIN, PL) 0
 #elif !defined(__GNUC_MINOR__)
 #  define ERTS_AT_LEAST_GCC_VSN__(MAJ, MIN, PL) \
@@ -34,9 +34,6 @@
   (((__GNUC__ << 24) | (__GNUC_MINOR__ << 12) | __GNUC_PATCHLEVEL__) >= (((MAJ) << 24) | ((MIN) << 12) | (PL)))
 #endif
 
-#if defined(ERTS_DIRTY_SCHEDULERS) && !defined(ERTS_SMP)
-# error "Dirty schedulers not supported without smp support"
-#endif
 
 #ifdef ERTS_INLINE
 #  ifndef ERTS_CAN_INLINE
@@ -221,12 +218,6 @@ __decl_noreturn void __noreturn erl_assert_error(const char* expr, const char *f
 #  define ASSERT(e) ((void) 1)
 #endif
 
-#ifdef ERTS_SMP
-#  define ERTS_SMP_ASSERT(e) ASSERT(e)
-#else
-#  define ERTS_SMP_ASSERT(e) ((void)1)
-#endif
-
 /* ERTS_UNDEF can be used to silence false warnings about
  * "variable may be used uninitialized" while keeping the variable
  * marked as undefined by valgrind.
@@ -327,9 +318,9 @@ __decl_noreturn void __noreturn erl_assert_error(const char* expr, const char *f
 #endif
 
 #if SIZEOF_VOID_P == SIZEOF_LONG
-typedef unsigned long Eterm;
-typedef unsigned long Uint;
-typedef long          Sint;
+typedef unsigned long Eterm erts_align_attribute(sizeof(long));
+typedef unsigned long Uint  erts_align_attribute(sizeof(long));
+typedef long          Sint  erts_align_attribute(sizeof(long));
 #define SWORD_CONSTANT(Const) Const##L
 #define UWORD_CONSTANT(Const) Const##UL
 #define ERTS_UWORD_MAX ULONG_MAX
@@ -337,9 +328,9 @@ typedef long          Sint;
 #define ERTS_SIZEOF_ETERM SIZEOF_LONG
 #define ErtsStrToSint strtol
 #elif SIZEOF_VOID_P == SIZEOF_INT
-typedef unsigned int Eterm;
-typedef unsigned int Uint;
-typedef int          Sint;
+typedef unsigned int Eterm erts_align_attribute(sizeof(int));
+typedef unsigned int Uint  erts_align_attribute(sizeof(int));
+typedef int          Sint  erts_align_attribute(sizeof(int));
 #define SWORD_CONSTANT(Const) Const
 #define UWORD_CONSTANT(Const) Const##U
 #define ERTS_UWORD_MAX UINT_MAX
@@ -347,9 +338,9 @@ typedef int          Sint;
 #define ERTS_SIZEOF_ETERM SIZEOF_INT
 #define ErtsStrToSint strtol
 #elif SIZEOF_VOID_P == SIZEOF_LONG_LONG
-typedef unsigned long long Eterm;
-typedef unsigned long long Uint;
-typedef long long          Sint;
+typedef unsigned long long Eterm erts_align_attribute(sizeof(long long));
+typedef unsigned long long Uint  erts_align_attribute(sizeof(long long));
+typedef long long          Sint  erts_align_attribute(sizeof(long long));
 #define SWORD_CONSTANT(Const) Const##LL
 #define UWORD_CONSTANT(Const) Const##ULL
 #define ERTS_UWORD_MAX ULLONG_MAX
@@ -470,41 +461,25 @@ typedef union {
 
 #include "erl_lock_check.h"
 
-/* needed by erl_smp.h */
+/* needed by erl_threads.h */
 int erts_send_warning_to_logger_str_nogl(char *);
 
-#include "erl_smp.h"
+#include "erl_threads.h"
 
 #ifdef ERTS_WANT_BREAK_HANDLING
-#  ifdef ERTS_SMP
-extern erts_smp_atomic32_t erts_break_requested;
+extern erts_atomic32_t erts_break_requested;
 #    define ERTS_BREAK_REQUESTED \
-  ((int) erts_smp_atomic32_read_nob(&erts_break_requested))
-#  else
-extern volatile int erts_break_requested;
-#    define ERTS_BREAK_REQUESTED erts_break_requested
-#  endif
+  ((int) erts_atomic32_read_nob(&erts_break_requested))
 void erts_do_break_handling(void);
 #endif
 
-#if !defined(ERTS_SMP) && !defined(__WIN32__)
-extern volatile Uint erts_signal_state;
-#define ERTS_SIGNAL_STATE erts_signal_state
-void erts_handle_signal_state(void);
-#endif
 
-#ifdef ERTS_SMP
-extern erts_smp_atomic32_t erts_writing_erl_crash_dump;
+extern erts_atomic32_t erts_writing_erl_crash_dump;
 extern erts_tsd_key_t erts_is_crash_dumping_key;
 #define ERTS_SOMEONE_IS_CRASH_DUMPING \
-  ((int) erts_smp_atomic32_read_mb(&erts_writing_erl_crash_dump))
+  ((int) erts_atomic32_read_mb(&erts_writing_erl_crash_dump))
 #define ERTS_IS_CRASH_DUMPING \
   ((int) (SWord) erts_tsd_get(erts_is_crash_dumping_key))
-#else
-extern volatile int erts_writing_erl_crash_dump;
-#define ERTS_SOMEONE_IS_CRASH_DUMPING erts_writing_erl_crash_dump
-#define ERTS_IS_CRASH_DUMPING erts_writing_erl_crash_dump
-#endif
 
 /* Deal with memcpy() vs bcopy() etc. We want to use the mem*() functions,
    but be able to fall back on bcopy() etc on systems that don't have
@@ -600,8 +575,6 @@ __decl_noreturn void __noreturn erts_exit(int n, char*, ...);
     erts_exit(ERTS_ABORT_EXIT, "%s:%d:%s(): Internal error: %s\n", \
 	     __FILE__, __LINE__, __func__, What)
 
-Eterm erts_check_io_info(void *p);
-
 UWord erts_sys_get_page_size(void);
 
 /* Size of misc memory allocated from system dependent code */
@@ -643,7 +616,7 @@ int erts_send_info_to_logger_nogl(erts_dsprintf_buf_t *);
 int erts_send_warning_to_logger_nogl(erts_dsprintf_buf_t *);
 int erts_send_error_to_logger_nogl(erts_dsprintf_buf_t *);
 int erts_send_info_to_logger_str_nogl(char *);
-/* needed by erl_smp.h (declared above)
+/* needed by erl_threads.h (declared above)
    int erts_send_warning_to_logger_str_nogl(char *); */
 int erts_send_error_to_logger_str_nogl(char *);
 
@@ -764,11 +737,7 @@ extern char *erts_sys_ddll_error(int code);
 /*
  * System interfaces for startup.
  */
-void erts_sys_schedule_interrupt(int set);
-#ifdef ERTS_SMP
-void erts_sys_schedule_interrupt_timed(int, ErtsMonotonicTime);
 void erts_sys_main_thread(void);
-#endif
 
 extern int erts_sys_prepare_crash_dump(int secs);
 extern void erts_sys_pre_init(void);
@@ -821,7 +790,7 @@ void fini_getenv_state(GETENV_STATE *);
 typedef struct {
     int no_used_fds;
     int no_driver_select_structs;
-    int no_driver_event_structs;
+    int no_enif_select_structs;
 } ErtsCheckIoDebugInfo;
 int erts_check_io_debug(ErtsCheckIoDebugInfo *ip);
 
@@ -855,13 +824,16 @@ int erts_sys_unsetenv(char *key);
 char *erts_read_env(char *key);
 void erts_free_read_env(void *value);
 
-#if defined(ERTS_SMP)
-#if defined(ERTS_THR_HAVE_SIG_FUNCS) && !defined(ETHR_UNUSABLE_SIGUSRX)
+#if defined(ERTS_THR_HAVE_SIG_FUNCS) &&                         \
+    (!defined(ETHR_UNUSABLE_SIGUSRX) || defined(SIGRTMIN))
 extern void sys_thr_resume(erts_tid_t tid);
 extern void sys_thr_suspend(erts_tid_t tid);
-#define ERTS_SYS_SUSPEND_SIGNAL SIGUSR2
-#endif
-#endif
+#ifdef SIGRTMIN
+#define ERTS_SYS_SUSPEND_SIGNAL (SIGRTMIN+1)
+#else
+#define ERTS_SYS_SUSPEND_SIGNAL (SIGUSR2)
+#endif /* SIGRTMIN */
+#endif /* HAVE_SIG_FUNCS */
 
 /* utils.c */
 
@@ -1025,144 +997,6 @@ erts_refc_read(erts_refc_t *refcp, erts_aint_t min_val)
 
 #endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
-typedef erts_smp_atomic_t erts_smp_refc_t;
-
-ERTS_GLB_INLINE void erts_smp_refc_init(erts_smp_refc_t *refcp, erts_aint_t val);
-ERTS_GLB_INLINE void erts_smp_refc_inc(erts_smp_refc_t *refcp, erts_aint_t min_val);
-ERTS_GLB_INLINE erts_aint_t erts_smp_refc_inc_unless(erts_smp_refc_t *refcp,
-                                                     erts_aint_t unless_val,
-                                                     erts_aint_t min_val);
-ERTS_GLB_INLINE erts_aint_t erts_smp_refc_inctest(erts_smp_refc_t *refcp,
-                                                  erts_aint_t min_val);
-ERTS_GLB_INLINE void erts_smp_refc_dec(erts_smp_refc_t *refcp, erts_aint_t min_val);
-ERTS_GLB_INLINE erts_aint_t erts_smp_refc_dectest(erts_smp_refc_t *refcp,
-                                                  erts_aint_t min_val);
-ERTS_GLB_INLINE void erts_smp_refc_add(erts_smp_refc_t *refcp, erts_aint_t diff,
-                                       erts_aint_t min_val);
-ERTS_GLB_INLINE erts_aint_t erts_smp_refc_read(erts_smp_refc_t *refcp,
-                                               erts_aint_t min_val);
-
-#if ERTS_GLB_INLINE_INCL_FUNC_DEF
-
-ERTS_GLB_INLINE void
-erts_smp_refc_init(erts_smp_refc_t *refcp, erts_aint_t val)
-{
-    erts_smp_atomic_init_nob((erts_smp_atomic_t *) refcp, val);
-}
-
-ERTS_GLB_INLINE void
-erts_smp_refc_inc(erts_smp_refc_t *refcp, erts_aint_t min_val)
-{
-#ifdef ERTS_REFC_DEBUG
-    erts_aint_t val = erts_smp_atomic_inc_read_nob((erts_smp_atomic_t *) refcp);
-    if (val < min_val)
-	erts_exit(ERTS_ABORT_EXIT,
-		 "erts_smp_refc_inc(): Bad refc found (refc=%ld < %ld)!\n",
-		 val, min_val);
-#else
-    erts_smp_atomic_inc_nob((erts_smp_atomic_t *) refcp);
-#endif
-}
-
-ERTS_GLB_INLINE erts_aint_t
-erts_smp_refc_inc_unless(erts_smp_refc_t *refcp,
-                         erts_aint_t unless_val,
-                         erts_aint_t min_val)
-{
-    erts_aint_t val = erts_smp_atomic_read_nob((erts_smp_atomic_t *) refcp);
-    while (1) {
-        erts_aint_t exp, new;
-#ifdef ERTS_REFC_DEBUG
-        if (val < 0)
-            erts_exit(ERTS_ABORT_EXIT,
-                      "erts_smp_refc_inc_unless(): Bad refc found (refc=%ld < %ld)!\n",
-                      val, min_val);
-#endif
-        if (val == unless_val)
-            return val;
-        new = val + 1;
-        exp = val;
-        val = erts_smp_atomic_cmpxchg_nob((erts_smp_atomic_t *) refcp, new, exp);
-        if (val == exp)
-            return new;
-    }
-}
-
-
-ERTS_GLB_INLINE erts_aint_t
-erts_smp_refc_inctest(erts_smp_refc_t *refcp, erts_aint_t min_val)
-{
-    erts_aint_t val = erts_smp_atomic_inc_read_nob((erts_smp_atomic_t *) refcp);
-#ifdef ERTS_REFC_DEBUG
-    if (val < min_val)
-	erts_exit(ERTS_ABORT_EXIT,
-		 "erts_smp_refc_inctest(): Bad refc found (refc=%ld < %ld)!\n",
-		 val, min_val);
-#endif
-    return val;
-}
-
-ERTS_GLB_INLINE void
-erts_smp_refc_dec(erts_smp_refc_t *refcp, erts_aint_t min_val)
-{
-#ifdef ERTS_REFC_DEBUG
-    erts_aint_t val = erts_smp_atomic_dec_read_nob((erts_smp_atomic_t *) refcp);
-    if (val < min_val)
-	erts_exit(ERTS_ABORT_EXIT,
-		 "erts_smp_refc_dec(): Bad refc found (refc=%ld < %ld)!\n",
-		 val, min_val);
-#else
-    erts_smp_atomic_dec_nob((erts_smp_atomic_t *) refcp);
-#endif
-}
-
-ERTS_GLB_INLINE erts_aint_t
-erts_smp_refc_dectest(erts_smp_refc_t *refcp, erts_aint_t min_val)
-{
-    erts_aint_t val = erts_smp_atomic_dec_read_nob((erts_smp_atomic_t *) refcp);
-#ifdef ERTS_REFC_DEBUG
-    if (val < min_val)
-	erts_exit(ERTS_ABORT_EXIT,
-		 "erts_smp_refc_dectest(): Bad refc found (refc=%ld < %ld)!\n",
-		 val, min_val);
-#endif
-    return val;
-}
-
-ERTS_GLB_INLINE void
-erts_smp_refc_add(erts_smp_refc_t *refcp, erts_aint_t diff, erts_aint_t min_val)
-{
-#ifdef ERTS_REFC_DEBUG
-    erts_aint_t val = erts_smp_atomic_add_read_nob((erts_smp_atomic_t *) refcp, diff);
-    if (val < min_val)
-	erts_exit(ERTS_ABORT_EXIT,
-		 "erts_smp_refc_add(%ld): Bad refc found (refc=%ld < %ld)!\n",
-		 diff, val, min_val);
-#else
-    erts_smp_atomic_add_nob((erts_smp_atomic_t *) refcp, diff);
-#endif
-}
-
-ERTS_GLB_INLINE erts_aint_t
-erts_smp_refc_read(erts_smp_refc_t *refcp, erts_aint_t min_val)
-{
-    erts_aint_t val = erts_smp_atomic_read_nob((erts_smp_atomic_t *) refcp);
-#ifdef ERTS_REFC_DEBUG
-    if (val < min_val)
-	erts_exit(ERTS_ABORT_EXIT,
-		 "erts_smp_refc_read(): Bad refc found (refc=%ld < %ld)!\n",
-		 val, min_val);
-#endif
-    return val;
-}
-
-#endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
-
-
-#ifdef ERTS_ENABLE_KERNEL_POLL
-extern int erts_use_kernel_poll;
-#endif
-
 #define sys_memcpy(s1,s2,n)  memcpy(s1,s2,n)
 #define sys_memmove(s1,s2,n) memmove(s1,s2,n)
 #define sys_memcmp(s1,s2,n)  memcmp(s1,s2,n)
@@ -1341,4 +1175,52 @@ int erts_get_printable_characters(void);
 
 void erts_init_sys_common_misc(void);
 
+ERTS_GLB_INLINE Sint erts_raw_env_7bit_ascii_char_need(int encoding);
+ERTS_GLB_INLINE byte *erts_raw_env_7bit_ascii_char_put(byte c, byte *p,
+                                                       int encoding);
+ERTS_GLB_INLINE int  erts_raw_env_char_is_7bit_ascii_char(byte c, byte *p,
+                                                          int encoding);
+ERTS_GLB_INLINE byte *erts_raw_env_next_char(byte *p, int encoding);
+
+#if ERTS_GLB_INLINE_INCL_FUNC_DEF
+
+ERTS_GLB_INLINE Sint
+erts_raw_env_7bit_ascii_char_need(int encoding)
+{
+    return (encoding == ERL_FILENAME_WIN_WCHAR) ? 2 : 1;
+}
+
+ERTS_GLB_INLINE byte *
+erts_raw_env_7bit_ascii_char_put(byte c,
+                                 byte *p,
+                                 int encoding)
+{
+    *(p++) = c;
+    if (encoding == ERL_FILENAME_WIN_WCHAR)
+        *(p++) = 0;
+    return p;
+}
+
+ERTS_GLB_INLINE int
+erts_raw_env_char_is_7bit_ascii_char(byte c,
+                                     byte *p,
+                                     int encoding)
+{
+    if (encoding == ERL_FILENAME_WIN_WCHAR)
+        return (p[0] == c) & (p[1] == 0);
+    else
+        return p[0] == c;
+}
+
+ERTS_GLB_INLINE byte *
+erts_raw_env_next_char(byte *p, int encoding)
+{
+    if (encoding == ERL_FILENAME_WIN_WCHAR)
+        return p + 2;
+    else
+        return p + 1;
+}
+
+#endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
+
 #endif
diff --git a/erts/emulator/beam/trace_instrs.tab b/erts/emulator/beam/trace_instrs.tab
new file mode 100644
index 0000000000..3eee81c053
--- /dev/null
+++ b/erts/emulator/beam/trace_instrs.tab
@@ -0,0 +1,168 @@
+// -*- c -*-
+//
+// %CopyrightBegin%
+//
+// Copyright Ericsson AB 2017. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// %CopyrightEnd%
+//
+
+return_trace() {
+    ErtsCodeMFA* mfa = (ErtsCodeMFA *)(E[0]);
+
+    SWAPOUT;		/* Needed for shared heap */
+    ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
+    erts_trace_return(c_p, mfa, r(0), ERTS_TRACER_FROM_ETERM(E+1)/* tracer */);
+    ERTS_REQ_PROC_MAIN_LOCK(c_p);
+    SWAPIN;
+    c_p->cp = NULL;
+    SET_I((BeamInstr *) cp_val(E[2]));
+    E += 3;
+    Goto(*I);
+    //| -no_next
+}
+
+i_generic_breakpoint() {
+    BeamInstr real_I;
+    HEAVY_SWAPOUT;
+    real_I = erts_generic_breakpoint(c_p, erts_code_to_codeinfo(I), reg);
+    HEAVY_SWAPIN;
+    ASSERT(VALID_INSTR(real_I));
+    Goto(real_I);
+    //| -no_next
+}
+
+i_return_time_trace() {
+    BeamInstr *pc = (BeamInstr *) (UWord) E[0];
+    SWAPOUT;
+    erts_trace_time_return(c_p, erts_code_to_codeinfo(pc));
+    SWAPIN;
+    c_p->cp = NULL;
+    SET_I((BeamInstr *) cp_val(E[1]));
+    E += 2;
+    Goto(*I);
+    //| -no_next
+}
+
+i_return_to_trace() {
+    if (IS_TRACED_FL(c_p, F_TRACE_RETURN_TO)) {
+        Uint *cpp = (Uint*) E;
+        for(;;) {
+            ASSERT(is_CP(*cpp));
+            if (IsOpCode(*cp_val(*cpp), return_trace)) {
+                do
+                    ++cpp;
+                while (is_not_CP(*cpp));
+                cpp += 2;
+            } else if (IsOpCode(*cp_val(*cpp), i_return_to_trace)) {
+                do
+                    ++cpp;
+                while (is_not_CP(*cpp));
+            } else {
+                break;
+            }
+        }
+        SWAPOUT;		/* Needed for shared heap */
+        ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
+        erts_trace_return_to(c_p, cp_val(*cpp));
+        ERTS_REQ_PROC_MAIN_LOCK(c_p);
+        SWAPIN;
+    }
+    c_p->cp = NULL;
+    SET_I((BeamInstr *) cp_val(E[0]));
+    E += 1;
+    Goto(*I);
+    //| -no_next
+}
+
+i_yield() {
+    /* This is safe as long as REDS_IN(c_p) is never stored
+     * in c_p->arg_reg[0]. It is currently stored in c_p->def_arg_reg[5].
+     */
+    c_p->arg_reg[0] = am_true;
+    c_p->arity = 1; /* One living register (the 'true' return value) */
+    SWAPOUT;
+    $SET_CP_I_ABS($NEXT_INSTRUCTION);
+    c_p->current = NULL;
+    goto do_schedule;
+    //| -no_next
+}
+
+i_hibernate() {
+    HEAVY_SWAPOUT;
+    if (erts_hibernate(c_p, reg)) {
+        FCALLS = c_p->fcalls;
+        c_p->flags &= ~F_HIBERNATE_SCHED;
+        goto do_schedule;
+    } else {
+        HEAVY_SWAPIN;
+        I = handle_error(c_p, I, reg, &bif_export[BIF_hibernate_3]->info.mfa);
+        goto post_error_handling;
+    }
+    //| -no_next
+}
+
+// This is optimised as an instruction because
+// it has to be very very fast.
+
+i_perf_counter() {
+    ErtsSysPerfCounter ts;
+
+    ts = erts_sys_perf_counter();
+    if (IS_SSMALL(ts)) {
+        r(0) = make_small((Sint)ts);
+    } else {
+        $GC_TEST(0, ERTS_SINT64_HEAP_SIZE(ts), 0);
+        r(0) = make_big(HTOP);
+#if defined(ARCH_32)
+        if (ts >= (((Uint64) 1) << 32)) {
+            *HTOP = make_pos_bignum_header(2);
+            BIG_DIGIT(HTOP, 0) = (Uint) (ts & ((Uint) 0xffffffff));
+            BIG_DIGIT(HTOP, 1) = (Uint) ((ts >> 32) & ((Uint) 0xffffffff));
+            HTOP += 3;
+        }
+        else
+#endif
+            {
+                *HTOP = make_pos_bignum_header(1);
+                BIG_DIGIT(HTOP, 0) = (Uint) ts;
+                HTOP += 2;
+            }
+    }
+}
+
+i_debug_breakpoint() {
+    HEAVY_SWAPOUT;
+    I = call_error_handler(c_p, erts_code_to_codemfa(I), reg, am_breakpoint);
+    HEAVY_SWAPIN;
+    if (I) {
+        Goto(*I);
+    }
+    goto handle_error;
+    //| -no_next
+}
+
+
+
+//
+// Special jump instruction used for tracing. Takes an absolute
+// failure address.
+//
+
+trace_jump(Fail) {
+    //| -no_next
+    SET_I((BeamInstr *) $Fail);
+    Goto(*I);
+}
diff --git a/erts/emulator/beam/utils.c b/erts/emulator/beam/utils.c
index d7116bd2c3..993585be10 100644
--- a/erts/emulator/beam/utils.c
+++ b/erts/emulator/beam/utils.c
@@ -43,7 +43,6 @@
 #include "erl_printf.h"
 #include "erl_threads.h"
 #include "erl_lock_count.h"
-#include "erl_smp.h"
 #include "erl_time.h"
 #include "erl_thr_progress.h"
 #include "erl_thr_queue.h"
@@ -1932,27 +1931,6 @@ do_allocate_logger_message(Eterm gleader, Eterm **hp, ErlOffHeap **ohp,
     gl_sz = IS_CONST(gleader) ? 0 : size_object(gleader);
     sz = sz + gl_sz;
 
-#ifndef ERTS_SMP
-#ifdef USE_THREADS
-    if (!erts_get_scheduler_data()) /* Must be scheduler thread */
-	*p = NULL;
-    else
-#endif
-    {
-	*p = erts_whereis_process(NULL, 0, am_error_logger, 0, 0);
-	if (*p) {
-	    erts_aint32_t state = erts_smp_atomic32_read_acqb(&(*p)->state);
-	    if (state & (ERTS_PSFLG_RUNNING|ERTS_PSFLG_RUNNING_SYS))
-		*p = NULL;
-	}
-    }
-
-    if (!*p) {
-	return NIL;
-    }
-
-    /* So we have an error logger, lets build the message */
-#endif
     *bp = new_message_buffer(sz);
     *ohp = &(*bp)->off_heap;
     *hp = (*bp)->mem;
@@ -1970,20 +1948,12 @@ static void do_send_logger_message(Eterm *hp, ErlOffHeap *ohp, ErlHeapFragment *
 #ifdef HARDDEBUG
     erts_fprintf(stderr, "%T\n", message);
 #endif
-#ifdef ERTS_SMP
     {
 	Eterm from = erts_get_current_pid();
 	if (is_not_internal_pid(from))
 	    from = NIL;
 	erts_queue_error_logger_message(from, message, bp);
     }
-#else
-    {
-	ErtsMessage *mp = erts_alloc_message(0, NULL);
-	mp->data.heap_frag = bp;
-	erts_queue_message(p, 0, mp, message, am_system);
-    }
-#endif
 }
 
 /* error_logger !
@@ -3557,7 +3527,7 @@ store_external_or_ref_(Uint **hpp, ErlOffHeap* oh, Eterm ns)
     if (is_external_header(*from_hp)) {
 	ExternalThing *etp = (ExternalThing *) from_hp;
 	ASSERT(is_external(ns));
-	erts_smp_refc_inc(&etp->node->refc, 2);
+	erts_refc_inc(&etp->node->refc, 2);
     }
     else if (is_ordinary_ref_thing(from_hp))
 	return make_internal_ref(to_hp);
@@ -4712,22 +4682,6 @@ void
 erts_interval_init(erts_interval_t *icp)
 {
     erts_atomic64_init_nob(&icp->counter.atomic, 0);
-#ifdef DEBUG
-    icp->smp_api = 0;
-#endif
-}
-
-void
-erts_smp_interval_init(erts_interval_t *icp)
-{
-#ifdef ERTS_SMP
-    erts_interval_init(icp);
-#else
-    icp->counter.not_atomic = 0;
-#endif
-#ifdef DEBUG
-    icp->smp_api = 1;
-#endif
 }
 
 static ERTS_INLINE Uint64
@@ -4767,79 +4721,25 @@ ensure_later_interval_acqb(erts_interval_t *icp, Uint64 ic)
 Uint64
 erts_step_interval_nob(erts_interval_t *icp)
 {
-    ASSERT(!icp->smp_api);
     return step_interval_nob(icp);
 }
 
 Uint64
 erts_step_interval_relb(erts_interval_t *icp)
 {
-    ASSERT(!icp->smp_api);
     return step_interval_relb(icp);
 }
 
 Uint64
-erts_smp_step_interval_nob(erts_interval_t *icp)
-{
-    ASSERT(icp->smp_api);
-#ifdef ERTS_SMP
-    return step_interval_nob(icp);
-#else
-    return ++icp->counter.not_atomic;
-#endif
-}
-
-Uint64
-erts_smp_step_interval_relb(erts_interval_t *icp)
-{
-    ASSERT(icp->smp_api);
-#ifdef ERTS_SMP
-    return step_interval_relb(icp);
-#else
-    return ++icp->counter.not_atomic;
-#endif
-}
-
-Uint64
 erts_ensure_later_interval_nob(erts_interval_t *icp, Uint64 ic)
 {
-    ASSERT(!icp->smp_api);
     return ensure_later_interval_nob(icp, ic);
 }
 
 Uint64
 erts_ensure_later_interval_acqb(erts_interval_t *icp, Uint64 ic)
 {
-    ASSERT(!icp->smp_api);
-    return ensure_later_interval_acqb(icp, ic);
-}
-
-Uint64
-erts_smp_ensure_later_interval_nob(erts_interval_t *icp, Uint64 ic)
-{
-    ASSERT(icp->smp_api);
-#ifdef ERTS_SMP
-    return ensure_later_interval_nob(icp, ic);
-#else
-    if (icp->counter.not_atomic > ic)
-	return icp->counter.not_atomic;
-    else
-	return ++icp->counter.not_atomic;
-#endif
-}
-
-Uint64
-erts_smp_ensure_later_interval_acqb(erts_interval_t *icp, Uint64 ic)
-{
-    ASSERT(icp->smp_api);
-#ifdef ERTS_SMP
     return ensure_later_interval_acqb(icp, ic);
-#else
-    if (icp->counter.not_atomic > ic)
-	return icp->counter.not_atomic;
-    else
-	return ++icp->counter.not_atomic;
-#endif
 }
 
 /*
diff --git a/erts/emulator/drivers/common/efile_drv.c b/erts/emulator/drivers/common/efile_drv.c
deleted file mode 100644
index 3a7b3bb50c..0000000000
--- a/erts/emulator/drivers/common/efile_drv.c
+++ /dev/null
@@ -1,4249 +0,0 @@
-/*
- * %CopyrightBegin%
- *
- * Copyright Ericsson AB 1996-2017. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * %CopyrightEnd%
- */
-/*
- * Purpose: Provides file and directory operations.
- *
- * This file is generic, and does the work of decoding the commands
- * and encoding the responses.  System-specific functions are found in
- * the unix_efile.c and win_efile.c files.
- */
-
-/* Operations */
-
-#define FILE_OPEN		 1 /* Essential for startup */
-#define FILE_READ		 2
-#define FILE_LSEEK		 3
-#define FILE_WRITE		 4
-#define FILE_FSTAT		 5 /* Essential for startup */
-#define FILE_PWD                 6 /* Essential for startup */
-#define FILE_READDIR             7 /* Essential for startup */
-#define FILE_CHDIR               8
-#define FILE_FSYNC               9
-#define FILE_MKDIR              10
-#define FILE_DELETE             11
-#define FILE_RENAME             12
-#define FILE_RMDIR              13
-#define FILE_TRUNCATE           14
-#define FILE_READ_FILE          15 /* Essential for startup */
-#define FILE_WRITE_INFO		16
-#define FILE_LSTAT            	19
-#define FILE_READLINK        	20
-#define FILE_LINK             	21
-#define FILE_SYMLINK          	22
-#define FILE_CLOSE		23
-#define FILE_PWRITEV		24
-#define FILE_PREADV		25
-#define FILE_SETOPT		26
-#define FILE_IPREAD             27
-#define FILE_ALTNAME            28
-#define FILE_READ_LINE          29
-#define FILE_FDATASYNC          30
-#define FILE_FADVISE            31
-#define FILE_SENDFILE           32
-#define FILE_FALLOCATE          33
-#define FILE_CLOSE_ON_PORT_EXIT 34
-/* Return codes */
-
-#define FILE_RESP_OK         0
-#define FILE_RESP_ERROR      1
-#define FILE_RESP_DATA       2
-#define FILE_RESP_NUMBER     3
-#define FILE_RESP_INFO       4
-#define FILE_RESP_NUMERR     5
-#define FILE_RESP_LDATA      6
-#define FILE_RESP_N2DATA     7
-#define FILE_RESP_EOF        8
-#define FILE_RESP_FNAME      9
-#define FILE_RESP_ALL_DATA  10
-#define FILE_RESP_LFNAME    11
-
-/* Options */
-
-#define FILE_OPT_DELAYED_WRITE 0
-#define FILE_OPT_READ_AHEAD    1
-
-/* IPREAD variants */
-
-#define IPREAD_S32BU_P32BU 0
-
-/* Limits */
-
-#define FILE_SEGMENT_READ  (256*1024)
-#define FILE_SEGMENT_WRITE (256*1024)
-
-/* Internal */
-
-/* Set to 1 to test having read_ahead implicitly for read_line */ 
-#define ALWAYS_READ_LINE_AHEAD 0
-
-
-/* Must not be possible to get from malloc()! */
-#define FILE_FD_INVALID ((Sint)(-1))
-
-#ifdef HAVE_CONFIG_H
-#  include "config.h"
-#endif
-
-#include <ctype.h>
-#include <sys/types.h>
-#include <stdlib.h>
-
-/* Need (NON)BLOCKING macros for sendfile */
-#ifndef WANT_NONBLOCKING
-#define WANT_NONBLOCKING
-#endif
-
-#include "sys.h"
-
-#include "erl_driver.h"
-#include "erl_efile.h"
-#include "erl_threads.h"
-#include "gzio.h"
-#include "dtrace-wrapper.h" 
-
-
-static ErlDrvSysInfo sys_info;
-
-/* For explanation of this var, see comment for same var in erl_async.c */
-static unsigned gcc_optimizer_hack = 0;
-
-#ifdef  USE_VM_PROBES
-
-#define DTRACE_EFILE_BUFSIZ 128
-
-#define DTRACE_INVOKE_SETUP(op) \
-    do { DTRACE3(efile_drv_int_entry, d->sched_i1, d->sched_i2, op); } while (0)
-#define DTRACE_INVOKE_SETUP_BY_NAME(op) \
-    struct t_data *d = (struct t_data *) data ; \
-    DTRACE_INVOKE_SETUP(op)
-#define DTRACE_INVOKE_RETURN(op) \
-    do { DTRACE3(efile_drv_int_return, d->sched_i1, d->sched_i2, \
-                 op); } while (0) ; gcc_optimizer_hack++ ;
-
-/* Assign human-friendlier id numbers to scheduler & I/O worker threads */
-int             dt_driver_idnum = 0;
-int             dt_driver_io_worker_base = 5000;
-erts_mtx_t      dt_driver_mutex;
-pthread_key_t   dt_driver_key;
-
-typedef struct {
-    int         thread_num;
-    Uint64      tag;
-} dt_private;
-
-dt_private *get_dt_private(int);
-#else  /* USE_VM_PROBES */
-#define DTRACE_INVOKE_SETUP(op)            do {} while (0)
-#define DTRACE_INVOKE_SETUP_BY_NAME(op)    do {} while (0)
-#define DTRACE_INVOKE_RETURN(op)           do {} while (0)
-#endif  /* USE_VM_PROBES */
-
-/* #define TRACE 1 */
-#ifdef TRACE
-#    define TRACE_C(c) do { putchar(c); fflush(stdout); } while (0)
-#    define TRACE_S(s) do { fputs((s), stdout); fflush(stdout); } while (0)
-#    define TRACE_F(args) do { printf args ;fflush(stdout); } while (0)
-#else
-#    define TRACE_C(c) ((void)(0))
-#    define TRACE_S(s) ((void)(0))
-#    define TRACE_F(args) ((void)(0))
-#endif
-
-
-#ifdef USE_THREADS
-#define THRDS_AVAILABLE (sys_info.async_threads > 0)
-#ifdef HARDDEBUG /* HARDDEBUG in io.c is expected too */
-#define TRACE_DRIVER fprintf(stderr, "Efile: ")
-#else
-#define TRACE_DRIVER
-#endif
-#define MUTEX_INIT(m, p) do { IF_THRDS { TRACE_DRIVER; (m = driver_pdl_create(p)); } } while (0)
-#define MUTEX_LOCK(m)    do { IF_THRDS { TRACE_DRIVER; driver_pdl_lock(m);   } } while (0)
-#define MUTEX_UNLOCK(m)  do { IF_THRDS { TRACE_DRIVER; driver_pdl_unlock(m); } } while (0)
-#else
-#define THRDS_AVAILABLE (0)
-#define MUTEX_INIT(m, p)
-#define MUTEX_LOCK(m)
-#define MUTEX_UNLOCK(m)
-#endif
-#define IF_THRDS if (THRDS_AVAILABLE)
-
-
-#define SENDFILE_FLGS_USE_THREADS (1 << 0)
-/**
- * On DARWIN sendfile can deadlock with close if called in
- * different threads. So until Apple fixes so that sendfile
- * is not buggy we disable usage of the async pool for
- * DARWIN. The testcase t_sendfile_crashduring reproduces
- * this error when using +A 10 and enabling SENDFILE_FLGS_USE_THREADS.
- */
-#if defined(__APPLE__) && defined(__MACH__)
-#define USE_THRDS_FOR_SENDFILE(DATA) 0
-#else
-#define USE_THRDS_FOR_SENDFILE(DATA) (DATA->flags & SENDFILE_FLGS_USE_THREADS)
-#endif /* defined(__APPLE__) && defined(__MACH__) */
-
-
-
-#if 0
-/* Experimental, for forcing all file operations to use the same thread. */
-   static unsigned file_fixed_key = 1;
-#  define KEY(desc) (&file_fixed_key)
-#else
-#  define KEY(desc) (&(desc)->key)
-#endif
-
-#ifndef MAX
-#  define MAX(x, y) (((x) > (y)) ? (x) : (y))
-#endif
-
-#ifdef FILENAMES_16BIT
-#ifdef USE_VM_PROBES
-#error 16bit characters in filenames and dtrace in combination is not supported.
-#endif
-#  define FILENAME_BYTELEN(Str) filename_len_16bit(Str)
-#  define FILENAME_COPY(To,From) filename_cpy_16bit((To),(From)) 
-#  define FILENAME_CHARSIZE 2
-
-   static int filename_len_16bit(char *str) 
-   {
-       char *p = str;
-       while(*p != '\0' || p[1] != '\0') {
-	   p += 2;
-       }
-       return (p - str);
-   }
-
-   static void filename_cpy_16bit(char *to, char *from) 
-   {
-       while(*from != '\0' || from[1] != '\0') {
-	   *to++ = *from++;
-	   *to++ = *from++;
-       }
-       *to++ = *from++;
-       *to++ = *from++;
-   }
-
-#else
-#  define FILENAME_BYTELEN(Str) strlen(Str)
-#  define FILENAME_COPY(To,From) strcpy(To,From) 
-#  define FILENAME_CHARSIZE 1
-#endif
-
-#if     (MAXPATHLEN+1)*FILENAME_CHARSIZE+1 > BUFSIZ
-#  define    RESBUFSIZE  ((MAXPATHLEN+1)*FILENAME_CHARSIZE+1)
-#else
-#  define    RESBUFSIZE  BUFSIZ
-#endif
-
-#define READDIR_CHUNKS (5)
-
-
-
-#if ALWAYS_READ_LINE_AHEAD
-#define DEFAULT_LINEBUF_SIZE 2048
-#else
-#define DEFAULT_LINEBUF_SIZE 512 /* Small, it's usually discarded anyway */ 
-#endif
-
-typedef unsigned char uchar;
-
-static ErlDrvData file_start(ErlDrvPort port, char* command);
-static int file_init(void);
-static void file_stop(ErlDrvData);
-static void file_output(ErlDrvData, char* buf, ErlDrvSizeT len);
-static ErlDrvSSizeT file_control(ErlDrvData, unsigned int command,
-				 char* buf, ErlDrvSizeT len,
-				 char **rbuf, ErlDrvSizeT rlen);
-static void file_timeout(ErlDrvData);
-static void file_outputv(ErlDrvData, ErlIOVec*);
-static void file_async_ready(ErlDrvData, ErlDrvThreadData);
-static void file_flush(ErlDrvData);
-
-#ifdef HAVE_SENDFILE
-static void file_ready_output(ErlDrvData data, ErlDrvEvent event);
-static void file_stop_select(ErlDrvEvent event, void* _);
-#endif /* HAVE_SENDFILE */
-
-
-enum e_timer {timer_idle, timer_again, timer_write};
-#ifdef HAVE_SENDFILE
-enum e_sendfile {sending, not_sending};
-#define SENDFILE_USE_THREADS (1 << 0)
-#endif /* HAVE_SENDFILE */
-
-struct t_data;
-
-typedef struct {
-    SWord           fd;
-    ErlDrvPort      port;
-    unsigned int    key;      /* Async queue key */
-    unsigned        flags;    /* Original flags from FILE_OPEN. */
-    void          (*invoke)(void *);
-    struct t_data  *d;
-    void          (*free)(void *);
-    struct t_data  *cq_head;  /* Queue of incoming commands */
-    struct t_data  *cq_tail;  /* -""- */
-    enum e_timer    timer_state;
-#ifdef HAVE_SENDFILE
-    enum e_sendfile sendfile_state;
-#endif /* HAVE_SENDFILE */
-    size_t          read_bufsize;
-    ErlDrvBinary   *read_binp;
-    size_t          read_offset;
-    size_t          read_size;
-    size_t          write_bufsize;
-    unsigned long   write_delay;
-    int             write_error;
-    Efile_error     write_errInfo;
-    ErlDrvPDL       q_mtx;    /* Mutex for the driver queue, known by the emulator. Also used for
-				 mutual exclusion when accessing field(s) below. */
-    size_t          write_buffered;
-#ifdef USE_VM_PROBES
-    int             idnum;      /* Unique ID # for this driver thread/desc */
-    char            port_str[DTRACE_TERM_BUF_SIZE];
-#endif
-} file_descriptor;
-
-
-static int reply_error(file_descriptor*, Efile_error* errInfo);
-
-struct erl_drv_entry efile_driver_entry = {
-    file_init,
-    file_start,
-    file_stop,
-    file_output,
-    NULL,
-#ifdef HAVE_SENDFILE
-    file_ready_output,
-#else
-    NULL,
-#endif /* HAVE_SENDFILE */
-    "efile",
-    NULL,
-    NULL,
-    file_control,
-    file_timeout,
-    file_outputv,
-    file_async_ready,
-    file_flush,
-    NULL,
-    NULL,
-    ERL_DRV_EXTENDED_MARKER,
-    ERL_DRV_EXTENDED_MAJOR_VERSION,
-    ERL_DRV_EXTENDED_MINOR_VERSION,
-    ERL_DRV_FLAG_USE_PORT_LOCKING,
-    NULL,
-    NULL,
-#ifdef HAVE_SENDFILE
-    file_stop_select
-#else
-    NULL
-#endif /* HAVE_SENDFILE */
-};
-
-
-
-static int thread_short_circuit;
-
-#define DRIVER_ASYNC(level, desc, f_invoke, data, f_free) \
-if (thread_short_circuit >= (level)) { \
-    (*(f_invoke))(data); \
-    file_async_ready((ErlDrvData)(desc), (data)); \
-} else { \
-    driver_async((desc)->port, KEY(desc), (f_invoke), (data), (f_free)); \
-}
-
-
-
-struct t_pbuf_spec {
-    Sint64 offset;
-    size_t size;
-};
-
-struct t_pwritev {
-    ErlDrvPort         port;
-    ErlDrvPDL          q_mtx;
-    size_t             size;
-    unsigned           cnt;
-    unsigned           n;
-    struct t_pbuf_spec specs[1];
-};
-
-struct t_preadv {
-    ErlIOVec eiov;
-    unsigned n;
-    unsigned cnt;
-    size_t   size;
-    Sint64   offsets[1];
-};
-
-#define READDIR_BUFSIZE (8*1024)*READDIR_CHUNKS
-#if READDIR_BUFSIZE < (1 + (2 + MAXPATHLEN)*FILENAME_CHARSIZE*READDIR_CHUNKS)
-#  undef READDIR_BUFSIZE
-#  define READDIR_BUFSIZE (1 + (2 + MAXPATHLEN)*FILENAME_CHARSIZE*READDIR_CHUNKS)
-#endif
-
-struct t_readdir_buf {
-     struct t_readdir_buf *next;
-     size_t n;
-     char buf[READDIR_BUFSIZE];
-};
-
-struct t_data
-{
-    struct t_data *next;
-    int            command;
-    int            level;
-    void         (*invoke)(void *);
-    void         (*free)(void *);
-    void           *data_to_free; /* used by FILE_CLOSE_ON_PORT_EXIT only */
-    int            again;
-    int            reply;
-#ifdef  USE_VM_PROBES
-    int               sched_i1;
-    Uint64            sched_i2;
-    char              sched_utag[DTRACE_EFILE_BUFSIZ+1];
-#endif
-    int            result_ok;
-    Efile_error    errInfo;
-    int            flags;
-    SWord          fd;
-    int            is_fd_unused;
-    /**/
-    Efile_info        info;
-    EFILE_DIR_HANDLE  dir_handle; /* Handle to open directory. */
-    ErlDrvBinary     *bin;
-    int               drive;
-    size_t            n;
-    /*off_t             offset;*/
-    /*size_t            bytesRead; Bytes read from the file. */
-    /**/
-    union {
-	struct {
-	    Sint64 offset;
-	    int    origin;
-	    Sint64 location;
-	} lseek;
-	struct {
-	    ErlDrvPort    port;
-	    ErlDrvPDL     q_mtx;
-	    size_t        size;
-	    size_t        reply_size;
-	} writev;
-	struct t_pwritev pwritev;
-	struct t_preadv  preadv;
-	struct {
-	    ErlDrvBinary *binp;
-	    size_t        bin_offset;
-	    size_t        bin_size;
-	    size_t        size;
-	} read;
-	struct {
-	    ErlDrvBinary *binp; /* in - out */
-	    size_t        read_offset; /* in - out */
-	    size_t        read_size; /* in - out */
-	    size_t        nl_pos; /* out */
-	    short         nl_skip; /* out, 0 or 1 */
-#if !ALWAYS_READ_LINE_AHEAD
-	    short         read_ahead; /* in, bool */
-#endif
-	} read_line;
-	struct {
-	    ErlDrvBinary *binp;
-	    int           size;
-	    int           offset;
-	} read_file;
-	struct {
-	    struct t_readdir_buf *first_buf;
-	    struct t_readdir_buf *last_buf;
-	} read_dir;
-	struct {
-	    Sint64 offset;
-	    Sint64 length;
-	    int advise;
-	} fadvise;
-#ifdef HAVE_SENDFILE
-	struct {
-	    ErlDrvPort port;
-	    ErlDrvPDL q_mtx;
-	    int out_fd;
-	    off_t offset;
-	    Uint64 nbytes;
-	    Uint64 written;
-	} sendfile;
-#endif /* HAVE_SENDFILE */
-	struct {
-	    Sint64 offset;
-	    Sint64 length;
-	} fallocate;
-    } c;
-    char b[1];
-};
-
-#define EF_ALLOC(S)		driver_alloc((S))
-#define EF_REALLOC(P, S)	driver_realloc((P), (S))
-#define EF_SAFE_ALLOC(S)	ef_safe_alloc((S))
-#define EF_SAFE_REALLOC(P, S)	ef_safe_realloc((P), (S))
-#define EF_FREE(P)		do { if((P)) driver_free((P)); } while(0)
-
-static void *ef_safe_alloc(Uint s)
-{
-    void *p = EF_ALLOC(s);
-    if (!p) erts_exit(ERTS_ERROR_EXIT, "efile drv: Can't allocate %lu bytes of memory\n", (unsigned long)s);
-    return p;
-}
-
-/*********************************************************************
- * ErlIOVec manipulation functions.
- */
-
-/* char EV_CHAR_P(ErlIOVec *ev, int p, int q) */
-#define EV_CHAR_P(ev, p, q)			\
-    (((char *)(ev)->iov[q].iov_base) + (p))
-
-/* int EV_GET_CHAR(ErlIOVec *ev, char *p, int *pp, int *qp) */
-#define EV_GET_CHAR(ev, p, pp, qp) efile_ev_get_char(ev, p ,pp, qp)
-static int
-efile_ev_get_char(ErlIOVec *ev, char *p, size_t *pp, size_t *qp) {
-    if (*pp + 1 <= ev->iov[*qp].iov_len) {
-	*p = *EV_CHAR_P(ev, *pp, *qp);
-	if (*pp + 1 < ev->iov[*qp].iov_len)
-	    *pp += 1;
-	else {
-	    *qp += 1;
-	    *pp = 0;
-	}
-	return !0;
-    }
-    return 0;
-}
-
-/* Uint32 EV_UINT32(ErlIOVec *ev, int p, int q)*/
-#define EV_UINT32(ev, p, q)						\
-    ((Uint32) ((unsigned char *)(ev)->iov[q].iov_base)[p])
-
-/* int EV_GET_UINT32(ErlIOVec *ev, Uint32 *p, int *pp, int *qp) */
-#define EV_GET_UINT32(ev, p, pp, qp) efile_ev_get_uint32(ev, p, pp, qp)
-static int
-efile_ev_get_uint32(ErlIOVec *ev, Uint32 *p, size_t *pp, size_t *qp) {
-    if (*pp + 4 <= ev->iov[*qp].iov_len) {
-	*p = (EV_UINT32(ev, *pp,   *qp) << 24)
-	    | (EV_UINT32(ev, *pp + 1, *qp) << 16)
-	    | (EV_UINT32(ev, *pp + 2, *qp) << 8)
-	    | (EV_UINT32(ev, *pp + 3, *qp));
-	if (*pp + 4 < ev->iov[*qp].iov_len)
-	    *pp += 4;
-	else {
-	    *qp += 1;
-	    *pp = 0;
-	}
-	return !0;
-    }
-    return 0;
-}
-
-/* Uint64 EV_UINT64(ErlIOVec *ev, int p, int q)*/
-#define EV_UINT64(ev, p, q)						\
-    ((Uint64) ((unsigned char *)(ev)->iov[q].iov_base)[p])
-
-/* int EV_GET_UINT64(ErlIOVec *ev, Uint64 *p, int *pp, int *qp) */
-#define EV_GET_UINT64(ev, p, pp, qp) efile_ev_get_uint64(ev, p, pp, qp)
-static int
-efile_ev_get_uint64(ErlIOVec *ev, Uint64 *p, size_t *pp, size_t *qp) {
-    if (*pp + 8 <= ev->iov[*qp].iov_len) {
-	*p = (EV_UINT64(ev, *pp, *qp) << 56)
-	    | (EV_UINT64(ev, *pp + 1, *qp) << 48)
-	    | (EV_UINT64(ev, *pp + 2, *qp) << 40)
-	    | (EV_UINT64(ev, *pp + 3, *qp) << 32)
-	    | (EV_UINT64(ev, *pp + 4, *qp) << 24)
-	    | (EV_UINT64(ev, *pp + 5, *qp) << 16)
-	    | (EV_UINT64(ev, *pp + 6, *qp) << 8)
-	    | (EV_UINT64(ev, *pp + 7, *qp));
-	if (*pp + 8 < ev->iov[*qp].iov_len)
-	    *pp += 8;
-	else {
-	    *qp += 1;
-	    *pp = 0;
-	}
-	return !0;
-    }
-    return 0;
-}
-
-/* int EV_GET_SINT64(ErlIOVec *ev, Uint64 *p, int *pp, int *qp) */
-#define EV_GET_SINT64(ev, p, pp, qp) efile_ev_get_sint64(ev, p, pp, qp)
-static int
-efile_ev_get_sint64(ErlIOVec *ev, Sint64 *p, size_t *pp, size_t *qp) {
-    Uint64 *tmp = (Uint64*)p;
-    return EV_GET_UINT64(ev, tmp, pp, qp);
-}
-
-#if 0
-
-static void ev_clear(ErlIOVec *ev) {
-    ASSERT(ev);
-    ev->size = 0;
-    ev->vsize = 0;
-    ev->iov = NULL;
-    ev->binv = NULL;
-}
-
-/* Assumes that ->iov and ->binv were allocated with sys_alloc().
- */
-static void ev_free(ErlIOVec *ev) {
-    if (! ev) {
-	return;
-    }
-    if (ev->vsize > 0) {
-	int i;
-	ASSERT(ev->iov);
-	ASSERT(ev->binv);
-	for (i = 0; i < ev->vsize; i++) {
-	    if (ev->binv[i]) {
-		driver_free_binary(ev->binv[i]);
-	    }
-	}
-	EF_FREE(ev->iov);
-	EF_FREE(ev->binv);
-    }
-}
-
-/* Copy the contents from source to dest.
- * Data in binaries is not copied, just the pointers; 
- * and refc is incremented.
- */
-static ErlIOVec *ev_copy(ErlIOVec *dest, ErlIOVec *source) {
-    int *ip;
-    ASSERT(dest);
-    ASSERT(source);
-    if (source->vsize == 0) {
-	/* Empty source */
-	ev_clear(dest);
-	return dest;
-    }
-    /* Allocate ->iov and ->binv */
-    dest->iov = EF_ALLOC(sizeof(*dest->iov) * source->vsize);
-    if (! dest->iov) {
-	return NULL;
-    }
-    dest->binv = EF_ALLOC(sizeof(*dest->binv) * source->vsize);
-    if (! dest->binv) {
-	EF_FREE(dest->iov);
-	return NULL;
-    }
-    dest->size = source->size;
-    /* Copy one vector element at the time. 
-     * Use *ip as an alias for dest->vsize to improve readabiliy.
-     * Keep dest consistent in every iteration by using 
-     * dest->vsize==*ip as loop variable.
-     */
-    for (ip = &dest->vsize, *ip = 0;  *ip < source->vsize;  (*ip)++) {
-	if (source->iov[*ip].iov_len == 0) {
-	    /* Empty vector element */
-	    dest->iov[*ip].iov_len = 0;
-	    dest->iov[*ip].iov_base = NULL;
-	    dest->binv[*ip] = NULL;
-	} else {
-	    /* Non empty vector element */
-	    if (source->binv[*ip]) {
-		/* Contents in binary - copy pointers and increment refc */
-		dest->iov[*ip] = source->iov[*ip];
-		dest->binv[*ip] = source->binv[*ip];
-		driver_binary_inc_refc(source->binv[*ip]);
-	    } else {
-		/* Contents not in binary - allocate new binary and copy data */
-		if (! (dest->binv[*ip] = 
-		       driver_alloc_binary(source->iov[*ip].iov_len))) {
-		    goto failed;
-		}
-		sys_memcpy(dest->binv[*ip]->orig_bytes,
-			   source->iov[*ip].iov_base,
-			   source->iov[*ip].iov_len);
-		dest->iov[*ip].iov_base = dest->binv[*ip]->orig_bytes;
-		dest->iov[*ip].iov_len = source->iov[*ip].iov_len;
-	    }
-	}
-    }
-    return dest;
- failed:
-    ev_free(dest);
-    return NULL;
-}
-
-#endif
-
-
-
-/*********************************************************************
- * Command queue functions
- */
-
-static void cq_enq(file_descriptor *desc, struct t_data *d) {
-    ASSERT(d);
-    if (desc->cq_head) {
-	ASSERT(desc->cq_tail);
-	ASSERT(!desc->cq_tail->next);
-	desc->cq_tail = desc->cq_tail->next = d;
-    } else {
-	ASSERT(desc->cq_tail == NULL);
-	desc->cq_head = desc->cq_tail = d;
-    }
-    d->next = NULL;
-}
-
-static struct t_data *cq_deq(file_descriptor *desc) {
-    struct t_data *d = desc->cq_head;
-    ASSERT(d || (!d && !desc->cq_tail));
-    if (d) {
-	ASSERT(!d->next || (d->next && desc->cq_tail != d));
-	if ((desc->cq_head = d->next) == NULL) {
-	    ASSERT(desc->cq_tail == d);
-	    desc->cq_tail = NULL;
-	}
-    }	
-    return d;
-}
-
-
-/*********************************************************************
- * Driver entry point -> init
- */
-static int 
-file_init(void)
-{
-    char buf[21]; /* enough to hold any 64-bit integer */
-    size_t bufsz = sizeof(buf);
-    thread_short_circuit = (erl_drv_getenv("ERL_EFILE_THREAD_SHORT_CIRCUIT",
-					   buf,
-					   &bufsz) == 0
-			    ? atoi(buf)
-			    : 0);
-    driver_system_info(&sys_info, sizeof(ErlDrvSysInfo));
-
-    /* run initiation of efile_driver if needed */
-    efile_init();
-
-#ifdef  USE_VM_PROBES
-    erts_mtx_init(&dt_driver_mutex, "efile_drv dtrace mutex", NIL,
-        ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_IO);
-    pthread_key_create(&dt_driver_key, NULL);
-#endif  /* USE_VM_PROBES */
-
-    return 0;
-}
-
-
-/*********************************************************************
- * Driver entry point -> start
- */
-static ErlDrvData 
-file_start(ErlDrvPort port, char* command) 
-
-{
-    file_descriptor* desc;
-
-    if ((desc = (file_descriptor*) EF_ALLOC(sizeof(file_descriptor)))
-	== NULL) {
-	errno = ENOMEM;
-	return ERL_DRV_ERROR_ERRNO;
-    }
-    desc->fd = FILE_FD_INVALID;
-    desc->port = port;
-    desc->key = driver_async_port_key(port);
-    desc->flags = 0;
-    desc->invoke = NULL;
-    desc->d = NULL;
-    desc->free = NULL;
-    desc->cq_head = NULL;
-    desc->cq_tail = NULL;
-    desc->timer_state = timer_idle;
-#ifdef HAVE_SENDFILE
-    desc->sendfile_state = not_sending;
-#endif
-    desc->read_bufsize = 0;
-    desc->read_binp = NULL;
-    desc->read_offset = 0;
-    desc->read_size = 0;
-    desc->write_delay = 0L;
-    desc->write_bufsize = 0;
-    desc->write_error = 0;
-    MUTEX_INIT(desc->q_mtx, port); /* Refc is one, referenced by emulator now */
-    desc->write_buffered = 0;
-#ifdef  USE_VM_PROBES
-    dtrace_drvport_str(port, desc->port_str);
-    get_dt_private(0);           /* throw away return value */
-#endif  /* USE_VM_PROBES */
-    return (ErlDrvData) desc;
-}
-
-static void do_close(int flags, SWord fd) {
-    if (flags & EFILE_COMPRESSED) {
-	erts_gzclose((ErtsGzFile)(fd));
-    } else {
-	efile_closefile((int) fd);
-    }
-}
-
-static void invoke_close(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    DTRACE_INVOKE_SETUP(FILE_CLOSE);
-    d->again = 0;
-    do_close(d->flags, d->fd);
-    DTRACE_INVOKE_RETURN(FILE_CLOSE);
-}
-
-static void free_data(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-
-    switch (d->command) {
-    case FILE_OPEN:
-        if (d->is_fd_unused && d->fd != FILE_FD_INVALID) {
-            /* This is OK to do in scheduler thread because there can be no async op
-               ongoing for this fd here, as we exited during async open.
-               Ideally, this close should happen in an async thread too, but that would
-               require a substantial rewrite, as we are here because of a dead port and
-               cannot schedule async jobs for that port any more... */
-            do_close(d->flags, d->fd);
-        }
-        break;
-    case FILE_CLOSE_ON_PORT_EXIT:
-        EF_FREE(d->data_to_free);
-        break;
-    }
-
-    EF_FREE(data);
-}
-
-
-/*
- * Sends back an error reply to Erlang.
- */
-
-static void reply_posix_error(file_descriptor *desc, int posix_errno) {
-    char response[256];		/* Response buffer. */
-    char* s;
-    char* t;
-    
-    /*
-     * Contents of buffer sent back:
-     *
-     * +-----------------------------------------+
-     * | FILE_RESP_ERROR | Posix error id string |
-     * +-----------------------------------------+
-     */
-
-    TRACE_C('E');
-
-    response[0] = FILE_RESP_ERROR;
-    for (s = erl_errno_id(posix_errno), t = response+1; *s; s++, t++)
-	*t = tolower(*s);
-    driver_output2(desc->port, response, t-response, NULL, 0);
-}
-
-static void reply_Uint_posix_error(file_descriptor *desc, Uint num, 
-				   int posix_errno) {
-    char response[256];		/* Response buffer. */
-    char* s;
-    char* t;
-    
-    /*
-     * Contents of buffer sent back:
-     *
-     * +----------------------------------------------------------------------+
-     * | FILE_RESP_NUMERR | 64-bit number (big-endian) | Posix error id string |
-     * +----------------------------------------------------------------------+
-     */
-
-    TRACE_C('N');
-
-    response[0] = FILE_RESP_NUMERR;
-#if SIZEOF_VOID_P == 4
-    put_int32(0, response+1);
-#else
-    put_int32(num>>32, response+1);
-#endif
-    put_int32((Uint32)num, response+1+4);
-    for (s = erl_errno_id(posix_errno), t = response+1+4+4; *s; s++, t++)
-	*t = tolower(*s);
-    driver_output2(desc->port, response, t-response, NULL, 0);
-}
-
-#ifdef HAVE_SENDFILE
-static void reply_string_error(file_descriptor *desc, char* str) {
-    char response[256];		/* Response buffer. */
-    char* s;
-    char* t;
-
-    response[0] = FILE_RESP_ERROR;
-    for (s = str, t = response+1; *s; s++, t++)
-	*t = tolower(*s);
-    driver_output2(desc->port, response, t-response, NULL, 0);
-}
-#endif
-
-static int reply_error(file_descriptor *desc, 
-		       Efile_error *errInfo) /* The error codes. */
-{
-    reply_posix_error(desc, errInfo->posix_errno);
-    return 0;
-}
-
-static int reply_Uint_error(file_descriptor *desc, Uint num, 
-			    Efile_error *errInfo) /* The error codes. */
-{
-    reply_Uint_posix_error(desc, num, errInfo->posix_errno);
-    return 0;
-}
-
-static int reply_ok(file_descriptor *desc) {
-    char c = FILE_RESP_OK;
-
-    driver_output2(desc->port, &c, 1, NULL, 0);
-    return 0;
-}
-
-static int reply(file_descriptor *desc, int ok, Efile_error *errInfo) {
-    if (!ok) {
-	reply_error(desc, errInfo);
-    } else {
-	TRACE_C('K');
-	reply_ok(desc);
-    }
-    return 0;
-}
-
-static int reply_Uint(file_descriptor *desc, Uint result) {
-    char tmp[1+4+4];
-
-    /*
-     * Contents of buffer sent back:
-     *
-     * +-----------------------------------------------+
-     * | FILE_RESP_NUMBER | 64-bit number (big-endian) |
-     * +-----------------------------------------------+
-     */
-
-    TRACE_C('R');
-
-    tmp[0] = FILE_RESP_NUMBER;
-#if SIZEOF_VOID_P == 4
-    put_int32(0, tmp+1);
-#else
-    put_int32(result>>32, tmp+1);
-#endif
-    put_int32((Uint32)result, tmp+1+4);
-    driver_output2(desc->port, tmp, sizeof(tmp), NULL, 0);
-    return 0;
-}
-
-static int reply_Sint64(file_descriptor *desc, Sint64 result) {
-    char tmp[1+4+4];
-
-    /*
-     * Contents of buffer sent back:
-     *
-     * +-----------------------------------------------+
-     * | FILE_RESP_NUMBER | 64-bit number (big-endian) |
-     * +-----------------------------------------------+
-     */
-
-    TRACE_C('R');
-
-    tmp[0] = FILE_RESP_NUMBER;
-    put_int64(result, tmp+1);
-    driver_output2(desc->port, tmp, sizeof(tmp), NULL, 0);
-    return 0;
-}
-
-#if 0
-static void reply_again(file_descriptor *desc) {
-    char tmp[1];
-    tmp[0] = FILE_RESP_AGAIN;
-    driver_output2(desc->port, tmp, sizeof(tmp), NULL, 0);
-}
-#endif
-
-static void reply_ev(file_descriptor *desc, char response, ErlIOVec *ev) {
-    char tmp[1];
-    /* Data arriving at the Erlang process:
-     * [Response, Binary0, Binary1, .... | BinaryN-1]
-     */
-    tmp[0] = response;
-    driver_outputv(desc->port, tmp, sizeof(tmp), ev, 0);
-}
-
-static void reply_data(file_descriptor *desc, 
-		       ErlDrvBinary *binp, size_t offset, size_t len) {
-    char header[1+4+4];
-    /* Data arriving at the Erlang process:
-     * [?FILE_RESP_DATA, 64-bit length (big-endian) | Data]
-     */
-    header[0] = FILE_RESP_DATA;
-#if SIZEOF_SIZE_T == 4
-    put_int32(0, header+1);
-#else
-    put_int32(len>>32, header+1);
-#endif
-    put_int32((Uint32)len, header+1+4);
-    driver_output_binary(desc->port, header, sizeof(header),
-			 binp, offset, len);
-}
-
-static void reply_buf(file_descriptor *desc, char *buf, size_t len) {
-    char header[1+4+4];
-    /* Data arriving at the Erlang process:
-     * [?FILE_RESP_DATA, 64-bit length (big-endian) | Data]
-     */
-    header[0] = FILE_RESP_DATA;
-#if SIZEOF_SIZE_T == 4
-    put_int32(0, header+1);
-#else
-    put_int32(len>>32, header+1);
-#endif
-    put_int32((Uint32)len, header+1+4);
-    driver_output2(desc->port, header, sizeof(header), buf, len);
-}
-
-static int reply_eof(file_descriptor *desc) {
-    char c = FILE_RESP_EOF;
-
-    driver_output2(desc->port, &c, 1, NULL, 0);
-    return 0;
-}
- 
-static void invoke_name(void *data, int (*f)(Efile_error *, char *))
-{
-    struct t_data *d = (struct t_data *) data;
-    char *name = (char *) d->b;
-
-    d->again = 0;
-    d->result_ok = (*f)(&d->errInfo, name);
-}
-
-static void invoke_mkdir(void *data)
-{
-    DTRACE_INVOKE_SETUP_BY_NAME(FILE_MKDIR);
-    invoke_name(data, efile_mkdir);
-    DTRACE_INVOKE_RETURN(FILE_MKDIR);
-}
-
-static void invoke_rmdir(void *data)
-{
-    DTRACE_INVOKE_SETUP_BY_NAME(FILE_RMDIR);
-    invoke_name(data, efile_rmdir);
-    DTRACE_INVOKE_RETURN(FILE_RMDIR);
-}
-
-static void invoke_delete_file(void *data)
-{
-    DTRACE_INVOKE_SETUP_BY_NAME(FILE_DELETE);
-    invoke_name(data, efile_delete_file);
-    DTRACE_INVOKE_RETURN(FILE_DELETE);
-}
-
-static void invoke_chdir(void *data)
-{
-    DTRACE_INVOKE_SETUP_BY_NAME(FILE_CHDIR);
-    invoke_name(data, efile_chdir);
-    DTRACE_INVOKE_RETURN(FILE_CHDIR);
-}
-
-static void invoke_fdatasync(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    int fd = (int) d->fd;
-    DTRACE_INVOKE_SETUP(FILE_FDATASYNC);
-
-    d->again = 0;
-    d->result_ok = efile_fdatasync(&d->errInfo, fd);
-    DTRACE_INVOKE_RETURN(FILE_FDATASYNC);
-}
-
-static void invoke_fsync(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    int fd = (int) d->fd;
-    DTRACE_INVOKE_SETUP(FILE_FSYNC);
-
-    d->again = 0;
-    d->result_ok = efile_fsync(&d->errInfo, fd);
-    DTRACE_INVOKE_RETURN(FILE_FSYNC);
-}
-
-static void invoke_truncate(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    int fd = (int) d->fd;
-    DTRACE_INVOKE_SETUP(FILE_TRUNCATE);
-
-    d->again = 0;
-    d->result_ok = efile_truncate_file(&d->errInfo, &fd, d->flags);
-    DTRACE_INVOKE_RETURN(FILE_TRUNCATE);
-}
-
-static void invoke_read(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    int status, segment;
-    size_t size, read_size;
-    DTRACE_INVOKE_SETUP(FILE_READ);
-
-    segment = d->again && d->c.read.bin_size >= 2*FILE_SEGMENT_READ;
-    if (segment) {
-	size = FILE_SEGMENT_READ;
-    } else {
-	size = d->c.read.bin_size;
-    }
-    read_size = size;
-    if (d->flags & EFILE_COMPRESSED) {
-	read_size = erts_gzread((ErtsGzFile)d->fd,
-				d->c.read.binp->orig_bytes + d->c.read.bin_offset,
-				size);
-	status = (read_size != (size_t) -1);
-	if (!status) {
-	    d->errInfo.posix_errno = EIO;
-	}
-    } else {
-	status = efile_read(&d->errInfo, d->flags, (int) d->fd,
-			    d->c.read.binp->orig_bytes + d->c.read.bin_offset,
-			    size,
-			    &read_size);
-    }
-    if ( (d->result_ok = status)) {
-	ASSERT(read_size <= size);
-	d->c.read.bin_offset += read_size;
-	if (read_size < size || !segment) {
-	    d->c.read.bin_size = 0;
-	    d->again = 0;
-	} else {
-	    d->c.read.bin_size -= read_size;
-	}
-    } else {
-	d->again = 0;
-    }
-    DTRACE_INVOKE_RETURN(FILE_READ);
-}
-
-static void free_read(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-
-    driver_free_binary(d->c.read.binp);
-    EF_FREE(d);
-}
-
-static void invoke_read_line(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    int status;
-    size_t read_size = 0;
-    int local_loop = (d->again == 0);
-    DTRACE_INVOKE_SETUP(FILE_READ_LINE);
-
-    do {
-	size_t size = (d->c.read_line.binp)->orig_size - 
-	    d->c.read_line.read_offset - d->c.read_line.read_size;
-	if (size == 0) {
-	    /* Need more place */
-	    ErlDrvSizeT need = (d->c.read_line.read_size >= DEFAULT_LINEBUF_SIZE) ?
-		d->c.read_line.read_size + DEFAULT_LINEBUF_SIZE : DEFAULT_LINEBUF_SIZE;
-	    ErlDrvBinary   *newbin;
-#if !ALWAYS_READ_LINE_AHEAD
-	    /* Use read_ahead size if need does not exceed it */
-	    if (need < (d->c.read_line.binp)->orig_size && 
-		d->c.read_line.read_ahead)
-	      need = (d->c.read_line.binp)->orig_size;
-#endif
-	    newbin = driver_alloc_binary(need);
-	    if (newbin == NULL) {
-		d->result_ok = 0;
-		d->errInfo.posix_errno = ENOMEM;
-		d->again = 0;
-		break;
-	    }
-	    memcpy(newbin->orig_bytes, (d->c.read_line.binp)->orig_bytes + d->c.read_line.read_offset,  
-		   d->c.read_line.read_size);
-	    driver_free_binary(d->c.read_line.binp);
-	    d->c.read_line.binp = newbin;
-	    d->c.read_line.read_offset = 0;
-	    size = need - d->c.read_line.read_size;
-	}
-	if (d->flags & EFILE_COMPRESSED) {
-	    read_size = erts_gzread((ErtsGzFile)d->fd,
-				    d->c.read_line.binp->orig_bytes + 
-				    d->c.read_line.read_offset + d->c.read_line.read_size,
-				    size);
-	    status = (read_size != (size_t) -1);
-	    if (!status) {
-		d->errInfo.posix_errno = EIO;
-	    }
-	} else {
-	    status = efile_read(&d->errInfo, d->flags, (int) d->fd,
-				d->c.read_line.binp->orig_bytes + 
-				d->c.read_line.read_offset + d->c.read_line.read_size,
-				size,
-				&read_size);
-	}
-	if ( (d->result_ok = status)) {
-	    void *nl_ptr = memchr((d->c.read_line.binp)->orig_bytes + 
-				  d->c.read_line.read_offset + d->c.read_line.read_size,'\n',read_size);
-	    ASSERT(read_size <= size);
-	    d->c.read_line.read_size += read_size;
-	    if (nl_ptr != NULL) {
-		/* If found, we're done */
-		d->c.read_line.nl_pos = ((char *) nl_ptr) - 
-		    ((char *) ((d->c.read_line.binp)->orig_bytes)) + 1;
-		if (d->c.read_line.nl_pos > 1 &&
-		    *(((char *) nl_ptr) - 1) == '\r') {
-		    --d->c.read_line.nl_pos;
-		    *(((char *) nl_ptr) - 1) = '\n';
-		    d->c.read_line.nl_skip = 1;
-		} else {
-		    d->c.read_line.nl_skip = 0;
-		}
-		d->again = 0;
-#if !ALWAYS_READ_LINE_AHEAD
-		if (!(d->c.read_line.read_ahead)) {
-		    /* Ouch! Undo buffering... */
-		    size_t too_much = d->c.read_line.read_size - d->c.read_line.nl_skip - 
-			(d->c.read_line.nl_pos - d->c.read_line.read_offset);
-		    d->c.read_line.read_size -= too_much;
-		    ASSERT(d->c.read_line.read_size >= 0);
-		    if (d->flags & EFILE_COMPRESSED) {
-			Sint64 location = erts_gzseek((ErtsGzFile)d->fd,
-						      -((Sint64) too_much), EFILE_SEEK_CUR);
-			if (location == -1) {
-			    d->result_ok = 0;
-			    d->errInfo.posix_errno = errno;
-			}
-		    } else {
-			Sint64 location;
-			d->result_ok = efile_seek(&d->errInfo, (int) d->fd, 
-						-((Sint64) too_much), EFILE_SEEK_CUR,
-						&location);
-		    }
-		}
-#endif
-		break;
-	    } else if (read_size == 0) {
-		d->c.read_line.nl_pos = 
-		    d->c.read_line.read_offset + d->c.read_line.read_size;
-		d->c.read_line.nl_skip = 0;
-		d->again = 0;
-		break;
-	    }
-	} else {
-	    d->again = 0;
-	    break;
-	}
-    } while (local_loop);
-    DTRACE_INVOKE_RETURN(FILE_READ_LINE);
-}
-
-static void free_read_line(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-
-    driver_free_binary(d->c.read_line.binp);
-    EF_FREE(d);
-}
-
-static void invoke_read_file(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    size_t read_size;
-    int chop;
-    DTRACE_INVOKE_SETUP(FILE_READ_FILE);
-    
-    if (! d->c.read_file.binp) { /* First invocation only */
-	int fd;
-	Sint64 size;
-	
-	if (! (d->result_ok = 
-	       efile_openfile(&d->errInfo, d->b, 
-			      EFILE_MODE_READ, &fd, &size))) {
-	    goto done;
-	}
-	d->fd = fd;
-	d->c.read_file.size = (int) size;
-	if (size < 0 || size != d->c.read_file.size ||
-	    ! (d->c.read_file.binp = 
-	       driver_alloc_binary(d->c.read_file.size))) {
-	    d->result_ok = 0;
-	    d->errInfo.posix_errno = ENOMEM;
-	    goto close;
-	}
-	d->c.read_file.offset = 0;
-    }
-    /* Invariant: d->c.read_file.size >= d->c.read_file.offset */
-    
-    read_size = (size_t) (d->c.read_file.size - d->c.read_file.offset);
-    if (! read_size) goto close;
-    chop = d->again && read_size >= FILE_SEGMENT_READ*2;
-    if (chop) read_size = FILE_SEGMENT_READ;
-    d->result_ok = 
-	efile_read(&d->errInfo, 
-		   EFILE_MODE_READ, 
-		   (int) d->fd, 
-		   d->c.read_file.binp->orig_bytes + d->c.read_file.offset,
-		   read_size, 
-		   &read_size);
-    if (d->result_ok) {
-	d->c.read_file.offset += read_size;
-	if (chop) goto chop_done; /* again */
-    }
- close:
-    efile_closefile((int) d->fd);
- done:
-    d->again = 0;
- chop_done:
-    DTRACE_INVOKE_RETURN(FILE_READ_FILE);
-}
-
-static void free_read_file(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-
-    if (d->c.read_file.binp) driver_free_binary(d->c.read_file.binp);
-    EF_FREE(d);
-}
-
-
-
-static void invoke_preadv(void *data)
-{
-    struct t_data   *d = (struct t_data *) data;
-    struct t_preadv *c = &d->c.preadv;
-    ErlIOVec        *ev = &c->eiov;
-    size_t           bytes_read_so_far = 0;
-    unsigned char   *p = (unsigned char *)ev->iov[0].iov_base + 4+4+8*c->cnt;
-    DTRACE_INVOKE_SETUP(FILE_PREADV);
-
-    while (c->cnt < c->n) {
-	size_t read_size = ev->iov[1 + c->cnt].iov_len - c->size;
-	size_t bytes_read = 0;
-	int chop = d->again 
-	    && bytes_read_so_far + read_size >= 2*FILE_SEGMENT_READ;
-	if (chop) {
-	    ASSERT(bytes_read_so_far < FILE_SEGMENT_READ);
-	    read_size = FILE_SEGMENT_READ + FILE_SEGMENT_READ/2
-		- bytes_read_so_far;
-	}
-	if ( (d->result_ok 
-	      = efile_pread(&d->errInfo, 
-			    (int) d->fd,
-			    c->offsets[c->cnt] + c->size,
-			    ((char *)ev->iov[1 + c->cnt].iov_base) + c->size,
-			    read_size,
-			    &bytes_read))) {
-	    bytes_read_so_far += bytes_read;
-	    if (chop && bytes_read == read_size) {
-		c->size += bytes_read;
-		goto done;
-	    }
-	    ASSERT(bytes_read <= read_size);
-	    ev->iov[1 + c->cnt].iov_len = bytes_read + c->size;
-	    ev->size += bytes_read + c->size;
-	    put_int64(bytes_read + c->size, p); p += 8;
-	    c->size = 0;
-	    c->cnt++;
-	    if (d->again 
-		&& bytes_read_so_far >= FILE_SEGMENT_READ
-		&& c->cnt < c->n) {
-		goto done;
-	    }
-	} else {
-	    /* In case of a read error, ev->size will not be correct,
-	     * which does not matter since no read data is returned
-	     * to Erlang.
-	     */
-	    break;
-	}
-    }					
-    d->again = 0;
- done:
-    DTRACE_INVOKE_RETURN(FILE_PREADV);
-}
-
-static void free_preadv(void *data) {
-    struct t_data *d = data;
-    int            i;
-    ErlIOVec      *ev = &d->c.preadv.eiov;
-    
-    for(i = 0; i < ev->vsize; i++) {
-	driver_free_binary(ev->binv[i]);
-    }
-    EF_FREE(d);
-}
-
-static void invoke_ipread(void *data)
-{
-    struct t_data   *d = data;
-    struct t_preadv *c = &d->c.preadv;
-    ErlIOVec        *ev = &c->eiov;
-    size_t bytes_read = 0;
-    char buf[2*sizeof(Uint32)];
-    Uint32 offset, size;
-    DTRACE_INVOKE_SETUP(FILE_IPREAD);
-    
-    /* Read indirection header */
-    if (! efile_pread(&d->errInfo, (int) d->fd, c->offsets[0], 
-		      buf, sizeof(buf), &bytes_read)) {
-	goto error;
-    }
-    if (bytes_read != sizeof(buf)) goto done; /* eof */
-    size = get_int32(buf);
-    offset = get_int32(buf+4);
-    if (size > c->size) goto done; /* eof */
-    c->n = 1;
-    c->cnt = 0;
-    c->size = 0;
-    c->offsets[0] = offset;
-    if (! (ev->binv[0] = driver_alloc_binary(3*8))) {
-	d->errInfo.posix_errno = ENOMEM;
-	goto error;
-    }
-    ev->vsize = 1;
-    ev->iov[0].iov_len = 3*8;
-    ev->iov[0].iov_base = ev->binv[0]->orig_bytes;
-    ev->size = ev->iov[0].iov_len;
-    put_int64(offset, ev->iov[0].iov_base);
-    put_int64(size, ((char *)ev->iov[0].iov_base) + 2*8);
-    if (size == 0) {
-	put_int64(size, ((char *)ev->iov[0].iov_base) + 8);
-	goto done;
-    }
-    if (! (ev->binv[1] = driver_alloc_binary(size))) {
-	d->errInfo.posix_errno = ENOMEM;
-	goto error;
-    }
-    ev->vsize = 2;
-    ev->iov[1].iov_len = size;
-    ev->iov[1].iov_base = ev->binv[1]->orig_bytes;
-    /* Read data block */
-    d->invoke = invoke_preadv;
-    invoke_preadv(data);
-    DTRACE_INVOKE_RETURN(FILE_IPREAD);
-    return;
- error:
-    d->result_ok = 0;
-    d->again = 0;
-    DTRACE_INVOKE_RETURN(FILE_IPREAD);
-    return;
- done:
-    d->result_ok = !0;
-    d->again = 0;
-    DTRACE_INVOKE_RETURN(FILE_IPREAD);
-}
-
-/* invoke_writev and invoke_pwritev are the only thread functions that
- * access non-thread data i.e the port queue and a mutex in the port
- * structure that is used to lock the port queue.
- *
- * The port will normally not be terminated until the port queue is
- * empty, but if the port is killed, i.e., exit(Port, kill) is called,
- * it will terminate regardless of the port queue state. When the
- * port is invalid driver_peekq() returns NULL and set the size to -1,
- * and driver_sizeq() returns -1.
- */
-
-static void invoke_writev(void *data) {
-    struct t_data *d = (struct t_data *) data;
-    SysIOVec      *iov0;
-    SysIOVec      *iov;
-    int            iovlen;
-    int            iovcnt;
-    size_t         size;
-    size_t         p;
-    int            segment;
-    DTRACE_INVOKE_SETUP(FILE_WRITE);
-
-    segment = d->again && d->c.writev.size >= 2*FILE_SEGMENT_WRITE;
-    if (segment) {
-	size = FILE_SEGMENT_WRITE;
-    } else {
-	size = d->c.writev.size;
-    }
-
-    /* Copy the io vector to avoid locking the port que while writing,
-     * also, both we and efile_writev might/will change the SysIOVec
-     * when segmenting or due to partial write and we do not want to
-     * tamper with the actual queue that we get from driver_peekq
-     */
-    MUTEX_LOCK(d->c.writev.q_mtx); /* Lock before accessing the port queue */
-    iov0 = driver_peekq(d->c.writev.port, &iovlen);
-
-    /* Calculate iovcnt */
-    for (p = 0, iovcnt = 0;
-	 p < size && iovcnt < iovlen;
-	 p += iov0[iovcnt++].iov_len)
-	;
-    iov = EF_SAFE_ALLOC(sizeof(SysIOVec)*iovcnt);
-    memcpy(iov,iov0,iovcnt*sizeof(SysIOVec));
-    MUTEX_UNLOCK(d->c.writev.q_mtx);
-    /* Let go of lock until we deque from original vector */
-
-    if (iovlen > 0) {
-	ASSERT(iov[iovcnt-1].iov_len > p - size);
-	iov[iovcnt-1].iov_len -= p - size;
-	if (d->flags & EFILE_COMPRESSED) {
-	    int i, status = 1;
-	    for (i = 0; i < iovcnt; i++) {
-		if (iov[i].iov_base && iov[i].iov_len > 0) {
-		    /* Just in case, I do not know what gzwrite does
-		     * with errno.
-		     */
-		    errno = EINVAL; 
-		    status = erts_gzwrite((ErtsGzFile)d->fd,
-					  iov[i].iov_base,
-					  iov[i].iov_len) == iov[i].iov_len;
-		    if (! status) {
-			d->errInfo.posix_errno =
-			    d->errInfo.os_errno = errno; /* XXX Correct? */
-			break;
-		    }
-		}
-	    }
-	    d->result_ok = status;
-	} else {
-	    d->result_ok = efile_writev(&d->errInfo, 
-					d->flags, (int) d->fd,
-					iov, iovcnt);
-	}
-    } else if (iovlen == 0) {
-	d->result_ok = 1;
-    }
-    else { /* Port has terminated */
-	d->result_ok = 0;
-	d->errInfo.posix_errno = d->errInfo.os_errno = EINVAL;
-    }
-    EF_FREE(iov);
-
-    if (! d->result_ok) {
-	d->again = 0;
-	MUTEX_LOCK(d->c.writev.q_mtx);
-	driver_deq(d->c.writev.port, d->c.writev.size);
-	MUTEX_UNLOCK(d->c.writev.q_mtx);
-    } else {
-	if (! segment) {
-	    d->again = 0;
-	}
-	d->c.writev.size -= size;
-	TRACE_F(("w%lu", (unsigned long)size));
-	MUTEX_LOCK(d->c.writev.q_mtx);
-	driver_deq(d->c.writev.port, size);
-	MUTEX_UNLOCK(d->c.writev.q_mtx);
-    }
-
-
-    DTRACE_INVOKE_RETURN(FILE_WRITE);
-}
-
-static void invoke_pwd(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    DTRACE_INVOKE_SETUP(FILE_PWD);
-
-    d->again = 0;
-    d->result_ok = efile_getdcwd(&d->errInfo,d->drive, d->b+1,
-				 RESBUFSIZE-1);
-    DTRACE_INVOKE_RETURN(FILE_PWD);
-}
-
-static void invoke_readlink(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    char resbuf[RESBUFSIZE];	/* Result buffer. */
-    DTRACE_INVOKE_SETUP(FILE_READLINK);
-
-    d->again = 0;
-    d->result_ok = efile_readlink(&d->errInfo, d->b, resbuf+1,
-				  RESBUFSIZE-1);
-    if (d->result_ok != 0)
-	FILENAME_COPY((char *) d->b + 1, resbuf+1);
-    DTRACE_INVOKE_RETURN(FILE_READLINK);
-}
-
-static void invoke_altname(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    char resbuf[RESBUFSIZE];	/* Result buffer. */
-    DTRACE_INVOKE_SETUP(FILE_ALTNAME);
-
-    d->again = 0;
-    d->result_ok = efile_altname(&d->errInfo, d->b, resbuf+1,
-				  RESBUFSIZE-1);
-    if (d->result_ok != 0)
-	FILENAME_COPY((char *) d->b + 1, resbuf+1);
-    DTRACE_INVOKE_RETURN(FILE_ALTNAME);
-}
-
-static void invoke_pwritev(void *data) {
-    struct t_data* const d = (struct t_data *) data;
-    struct t_pwritev * const c = &d->c.pwritev;
-    SysIOVec         *iov0;
-    SysIOVec         *iov;
-    int               iovlen;
-    int               iovcnt;
-    size_t            p;
-    int               segment;
-    size_t            size, write_size, written;
-    DTRACE_INVOKE_SETUP(FILE_PWRITEV);
-
-    segment = d->again && c->size >= 2*FILE_SEGMENT_WRITE;
-    if (segment) {
-	size = FILE_SEGMENT_WRITE;
-    } else {
-	size = c->size;
-    }
-    d->result_ok = !0;
-    p = 0;
-    /* Lock the queue just for a while, we don't want it locked during write */
-    MUTEX_LOCK(c->q_mtx);
-    iov0 = driver_peekq(c->port, &iovlen);
-    iov = EF_SAFE_ALLOC(sizeof(SysIOVec)*iovlen);
-    memcpy(iov,iov0,sizeof(SysIOVec)*iovlen);
-    MUTEX_UNLOCK(c->q_mtx);
-
-    if (iovlen < 0)
-	goto error; /* Port terminated */
-    for (iovcnt = 0, written = 0;
-	 c->cnt < c->n && iovcnt < iovlen && written < size;
-	 c->cnt++) {
-	int chop;
-	write_size = c->specs[c->cnt].size;
-	if (iov[iovcnt].iov_len - p < write_size) {
-	    goto error;
-	}
-	chop = segment && written + write_size >= 2*FILE_SEGMENT_WRITE;
-	if (chop) {
-	    ASSERT(written < FILE_SEGMENT_WRITE);
-	    write_size = FILE_SEGMENT_WRITE + FILE_SEGMENT_WRITE/2 
-		- written;
-	}
-	d->result_ok = efile_pwrite(&d->errInfo, (int) d->fd,
-				    (char *)(iov[iovcnt].iov_base) + p,
-				    write_size,
-				    c->specs[c->cnt].offset);
-	if (! d->result_ok) {
-	    d->again = 0;
-	    goto deq_error;
-	}
-	written += write_size; 
-	c->size -= write_size;
-	if (chop) { 
-	    c->specs[c->cnt].offset += write_size;
-	    c->specs[c->cnt].size -= write_size;
-	    /* Schedule out (d->again != 0) */
-	    break;
-	}
-	/* Move forward in buffer */
-	p += write_size;
-	ASSERT(iov[iovcnt].iov_len >= p);
-	if (iov[iovcnt].iov_len == p) {
-	    /* Move to next iov[], we trust that it is not a 
-	     * zero length vector, and thereby depend on that
-	     * such are not queued.
-	     */
-	    iovcnt++; p = 0;
-	}
-    }
-    if (! segment) {
-	if (c->cnt != c->n) {
-	    /* Mismatch between number of 
-	     * pos/size specs vs number of queued buffers .
-	     */
-	error:
-	    d->errInfo.posix_errno = EINVAL;
-	    d->result_ok = 0;
-	    d->again = 0;
-	deq_error:
-	    MUTEX_LOCK(c->q_mtx);
-	    driver_deq(c->port, c->size);
-	    MUTEX_UNLOCK(c->q_mtx);
-
-	    goto done;
-	} else {
-	    ASSERT(written == size);
-	    d->again = 0;
-	}
-    } else {
-      ASSERT(written >= FILE_SEGMENT_WRITE);
-    }
-      
-    MUTEX_LOCK(c->q_mtx);
-    driver_deq(c->port, written);
-    MUTEX_UNLOCK(c->q_mtx);
- done:
-    EF_FREE(iov); /* Free our copy of the vector, nothing to restore */
-    
-    DTRACE_INVOKE_RETURN(FILE_PWRITEV);
-}
-
-static void invoke_flstat(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-
-    DTRACE3(efile_drv_int_entry, d->sched_i1, d->sched_i2,
-            d->command == FILE_LSTAT ? FILE_LSTAT : FILE_FSTAT);
-    d->again = 0;
-    d->result_ok = efile_fileinfo(&d->errInfo, &d->info,
-				  d->b, d->command == FILE_LSTAT);
-    DTRACE3(efile_drv_int_entry, d->sched_i1, d->sched_i2,
-            d->command == FILE_LSTAT ? FILE_LSTAT : FILE_FSTAT);
-    gcc_optimizer_hack++;
-}
-
-static void invoke_link(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    char *name = d->b;
-    char *new_name;
-    DTRACE_INVOKE_SETUP(FILE_LINK);
-
-    d->again = 0;
-    new_name = name+FILENAME_BYTELEN(name)+FILENAME_CHARSIZE;
-    d->result_ok = efile_link(&d->errInfo, name, new_name);
-    DTRACE_INVOKE_RETURN(FILE_LINK);
-}
-
-static void invoke_symlink(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    char *name = d->b;
-    char *new_name;
-    DTRACE_INVOKE_SETUP(FILE_SYMLINK);
-
-    d->again = 0;
-    new_name = name+FILENAME_BYTELEN(name)+FILENAME_CHARSIZE;
-    d->result_ok = efile_symlink(&d->errInfo, name, new_name);
-    DTRACE_INVOKE_RETURN(FILE_SYMLINK);
-}
-
-static void invoke_rename(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    char *name = d->b;
-    char *new_name;
-    DTRACE_INVOKE_SETUP(FILE_RENAME);
-
-    d->again = 0;
-    new_name = name+FILENAME_BYTELEN(name)+FILENAME_CHARSIZE;
-    d->result_ok = efile_rename(&d->errInfo, name, new_name);
-    DTRACE_INVOKE_RETURN(FILE_RENAME);
-}
-
-static void invoke_write_info(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    DTRACE_INVOKE_SETUP(FILE_WRITE_INFO);
-
-    d->again = 0;
-    d->result_ok = efile_write_info(&d->errInfo, &d->info, d->b);
-    DTRACE_INVOKE_RETURN(FILE_WRITE_INFO);
-}
-
-static void invoke_lseek(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    int status;
-    DTRACE_INVOKE_SETUP(FILE_LSEEK);
-
-    d->again = 0;
-    if (d->flags & EFILE_COMPRESSED) {
-	int offset = (int) d->c.lseek.offset;
-	
-	if (offset != d->c.lseek.offset) {
-	    d->errInfo.posix_errno = EINVAL;
-	    status = 0;
-	} else {
-	    d->c.lseek.location = erts_gzseek((ErtsGzFile)d->fd,
-					      offset, d->c.lseek.origin);
-	    if (d->c.lseek.location == -1) {
-		d->errInfo.posix_errno = errno;
-		status = 0;
-	    } else {
-		status = 1;
-	    }
-	}
-    } else {
-	status = efile_seek(&d->errInfo, (int) d->fd, 
-			    d->c.lseek.offset, d->c.lseek.origin,
-			    &d->c.lseek.location);
-    }
-    d->result_ok = status;
-    DTRACE_INVOKE_RETURN(FILE_LSEEK);
-}
-
-static void invoke_readdir(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    char *p = NULL;
-    size_t file_bs;
-    size_t n = 0, total = 0;
-    struct t_readdir_buf *b = NULL;
-    int res = 0;
-    DTRACE_INVOKE_SETUP(FILE_READDIR);
-
-    d->again = 0;
-    d->errInfo.posix_errno = 0;
-
-    do {
-	total   = READDIR_BUFSIZE;
-	n       = 1;
-	b       = EF_SAFE_ALLOC(sizeof(struct t_readdir_buf));
-	b->next = NULL;
-	
-	if (d->c.read_dir.last_buf) {
-	    d->c.read_dir.last_buf->next = b;
-	} else {
-	    d->c.read_dir.first_buf = b;
-	}
-	d->c.read_dir.last_buf = b;
-
-	p       = &b->buf[0];
-	p[0]    = FILE_RESP_LFNAME;
-	file_bs = READDIR_BUFSIZE - n;
-
-	do {
-	    res = efile_readdir(&d->errInfo, d->b, &d->dir_handle, p + n + 2, &file_bs);
-
-	    if (res) {
-		put_int16((Uint16)file_bs, p + n);
-		n += 2 + file_bs;
-		file_bs = READDIR_BUFSIZE - n;
-	    }
-	} while( res && ((total - n - 2) >= MAXPATHLEN*FILENAME_CHARSIZE));
-
-	b->n = n;
-    } while(res);
-
-    d->result_ok = (d->errInfo.posix_errno == 0);
-    DTRACE_INVOKE_RETURN(FILE_READDIR);
-}
-
-static void invoke_open(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    int status = 1;		/* Status of open call. */
-    DTRACE_INVOKE_SETUP(FILE_OPEN);
-
-    d->again = 0;
-    if ((d->flags & EFILE_COMPRESSED) == 0) {
-	int fd;
-	status = efile_openfile(&d->errInfo, d->b, d->flags, &fd, NULL);
-	d->fd = fd;
-    } else {
-	char* mode = NULL;
-
-	if (((d->flags & (EFILE_MODE_READ_WRITE)) == EFILE_MODE_READ_WRITE) ||
-	    (d->flags & EFILE_MODE_APPEND)) {
-	    status = 0;
-	    d->errInfo.posix_errno = EINVAL;
-	} else {
-	    status = efile_may_openfile(&d->errInfo, d->b);
-	    if (status || (d->errInfo.posix_errno != EISDIR)) {
-		mode = (d->flags & EFILE_MODE_READ) ? "rb" : "wb";
-		d->fd = (SWord) erts_gzopen(d->b, mode);
-		if ((ErtsGzFile)d->fd) {
-		    status = 1;
-		} else {
-		    if (errno == 0) {
-			errno = ENOMEM;
-		    }
-		    d->errInfo.posix_errno = errno;
-		    status = 0;
-		}
-	    }
-	}
-    }
-
-    d->result_ok = status;
-    if (!status) {
-        d->fd = FILE_FD_INVALID;
-    }
-    DTRACE_INVOKE_RETURN(FILE_OPEN);
-}
-
-static void invoke_fadvise(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    int fd = (int) d->fd;
-    off_t offset = (off_t) d->c.fadvise.offset;
-    off_t length = (off_t) d->c.fadvise.length;
-    int advise = (int) d->c.fadvise.advise;
-    DTRACE_INVOKE_SETUP(FILE_FADVISE);
-
-    d->again = 0;
-    d->result_ok = efile_fadvise(&d->errInfo, fd, offset, length, advise);
-    DTRACE_INVOKE_RETURN(FILE_FADVISE);
-}
-
-#ifdef HAVE_SENDFILE
-static void invoke_sendfile(void *data)
-{
-    struct t_data *d = (struct t_data *)data;
-    int fd = d->fd;
-    int out_fd = (int)d->c.sendfile.out_fd;
-    Uint64 nbytes = d->c.sendfile.nbytes;
-    int result = 0;
-    d->again = 0;
-
-    result = efile_sendfile(&d->errInfo, fd, out_fd, &d->c.sendfile.offset, &nbytes, NULL);
-
-    d->c.sendfile.written += nbytes;
-
-    if (result == 1 || (result == 0 && USE_THRDS_FOR_SENDFILE(d))) {
-      d->result_ok = 0;
-    } else if (result == 0 && (d->errInfo.posix_errno == EAGAIN
-				 || d->errInfo.posix_errno == EINTR)) {
-      if ((d->c.sendfile.nbytes - nbytes) != 0) {
-	d->result_ok = 1;
-	if (d->c.sendfile.nbytes != 0)
-	  d->c.sendfile.nbytes -= nbytes;
-      } else if (nbytes == 0 && d->c.sendfile.nbytes == 0) {
-	d->result_ok = 1;
-      } else
-	d->result_ok = 0;
-    } else {
-	d->result_ok = -1;
-    }
-}
-
-static void free_sendfile(void *data) {
-    struct t_data *d = (struct t_data *)data;
-    if (USE_THRDS_FOR_SENDFILE(d)) {
-	SET_NONBLOCKING(d->c.sendfile.out_fd);
-    } else {
-	MUTEX_LOCK(d->c.sendfile.q_mtx);
-	driver_deq(d->c.sendfile.port,1);
-	MUTEX_UNLOCK(d->c.sendfile.q_mtx);
-	driver_select(d->c.sendfile.port, (ErlDrvEvent)(long)d->c.sendfile.out_fd,
-                      ERL_DRV_USE_NO_CALLBACK|ERL_DRV_WRITE, 0);
-    }
-    EF_FREE(data);
-}
-
-static void file_ready_output(ErlDrvData data, ErlDrvEvent event)
-{
-    file_descriptor* fd = (file_descriptor*) data;
-
-    switch (fd->d->command) {
-    case FILE_SENDFILE:
-	driver_select(fd->d->c.sendfile.port, event,
-		      (int)ERL_DRV_WRITE,(int) 0);
-	invoke_sendfile((void *)fd->d);
-	file_async_ready(data, (ErlDrvThreadData)fd->d);
-	break;
-    default:
-	break;
-    }
-}
-
-static void file_stop_select(ErlDrvEvent event, void* _)
-{
-
-}
-
-static int flush_sendfile(file_descriptor *desc,void *_) {
-    if (desc->sendfile_state == sending) {
-	desc->d->result_ok = -1;
-	desc->d->errInfo.posix_errno = ECONNABORTED;
-	file_async_ready((ErlDrvData)desc,(ErlDrvThreadData)desc->d);
-    }
-    return 1;
-}
-#endif /* HAVE_SENDFILE */
-
-
-static void invoke_fallocate(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    int fd = (int) d->fd;
-    Sint64 offset = d->c.fallocate.offset;
-    Sint64 length = d->c.fallocate.length;
-
-    d->again = 0;
-    d->result_ok = efile_fallocate(&d->errInfo, fd, offset, length);
-}
-
-static void free_readdir(void *data)
-{
-    struct t_data *d = (struct t_data *) data;
-    struct t_readdir_buf *b1 = d->c.read_dir.first_buf;
-
-    while (b1) {
-	struct t_readdir_buf *b2 = b1;
-	b1 = b1->next;
-	EF_FREE(b2);
-    }
-    EF_FREE(d);
-}
-
-
-
-static void try_free_read_bin(file_descriptor *desc) {
-    if ((desc->read_size == 0)
-	&& (desc->read_offset >= desc->read_binp->orig_size)) {
-	ASSERT(desc->read_offset == desc->read_binp->orig_size);
-	driver_free_binary(desc->read_binp);
-	desc->read_binp = NULL;
-	desc->read_offset = 0;
-	desc->read_size = 0;
-    }
-}
-
-
-
-static int try_again(file_descriptor *desc, struct t_data *d) {
-    if (! d->again)
-	return 0;
-    if (desc->timer_state != timer_idle) {
-	driver_cancel_timer(desc->port);
-    }
-    desc->timer_state = timer_again;
-    desc->invoke = d->invoke;
-    desc->d = d;
-    desc->free = d->free;
-    driver_set_timer(desc->port, 0L);
-    return !0;
-}
-
-
-
-static void cq_execute(file_descriptor *desc) {
-    struct t_data *d;
-    register void *void_ptr; /* Soft cast variable */
-    if (desc->timer_state == timer_again)
-	return;
-#ifdef HAVE_SENDFILE
-    if (desc->sendfile_state == sending)
-	return;
-#endif
-    if (! (d = cq_deq(desc)))
-	return;
-    TRACE_F(("x%i", (int) d->command));
-    d->again = sys_info.async_threads == 0;
-    DRIVER_ASYNC(d->level, desc, d->invoke, void_ptr=d, d->free);
-}
-
-static struct t_data *async_write(file_descriptor *desc, int *errp,
-		       int reply, Uint32 reply_size
-#ifdef USE_VM_PROBES
-		       ,Sint64 *dt_i1, Sint64 *dt_i2, Sint64 *dt_i3
-#endif
-) {
-    struct t_data *d;
-    if (! (d = EF_ALLOC(sizeof(struct t_data) - 1))) {
-	if (errp) *errp = ENOMEM;
-	return NULL;
-    }
-    TRACE_F(("w%lu", (unsigned long)desc->write_buffered));
-    d->command = FILE_WRITE;
-    d->fd = desc->fd;
-    d->flags = desc->flags;
-    d->c.writev.port = desc->port;
-    d->c.writev.q_mtx = desc->q_mtx;
-    d->c.writev.size = desc->write_buffered;
-#ifdef USE_VM_PROBES
-    if (dt_i1 != NULL) {
-        *dt_i1 = d->fd;
-        *dt_i2 = d->flags;
-        *dt_i3 = d->c.writev.size;
-    }
-#endif
-    d->reply = reply;
-    d->c.writev.reply_size = reply_size;
-    d->invoke = invoke_writev;
-    d->free = free_data;
-    d->level = 1;
-    cq_enq(desc, d);
-    desc->write_buffered = 0;
-    return d;
-}
-
-static int flush_write(file_descriptor *desc, int *errp
-#ifdef USE_VM_PROBES
-                       , dt_private *dt_priv, char *dt_utag
-#endif
-) {
-    int    result = 0;
-#ifdef USE_VM_PROBES
-    Sint64 dt_i1 = 0, dt_i2 = 0, dt_i3 = 0;
-#endif
-    struct t_data *d = NULL;
-
-    MUTEX_LOCK(desc->q_mtx);
-    if (desc->write_buffered > 0) {
-	if ((d = async_write(desc, errp, 0, 0
-#ifdef USE_VM_PROBES
-			     ,&dt_i1, &dt_i2, &dt_i3
-#endif
-			     )) == NULL) {
-            result = -1;
-        }
-    }
-    MUTEX_UNLOCK(desc->q_mtx);
-#ifdef USE_VM_PROBES
-    if (d != NULL) {
-        d->sched_i1 = dt_priv->thread_num;
-        d->sched_i2 = dt_priv->tag;
-        d->sched_utag[0] = '\0';
-        if (dt_utag != NULL) {
-            if (dt_utag[0] == '\0') {
-                dt_utag = NULL;
-            } else {
-                strncpy(d->sched_utag, dt_utag, sizeof(d->sched_utag) - 1);
-                d->sched_utag[sizeof(d->sched_utag) - 1] = '\0';
-            }
-        }
-        DTRACE11(efile_drv_entry, dt_priv->thread_num, dt_priv->tag++,
-                 dt_utag, FILE_WRITE,
-                 NULL, NULL, dt_i1, dt_i2, dt_i3, 0, desc->port_str);
-    }
-#endif /* USE_VM_PROBES */
-    return result;
-}
-
-static int check_write_error(file_descriptor *desc, int *errp) {
-    if (desc->write_error) {
-	if (errp) *errp = desc->write_errInfo.posix_errno;
-	desc->write_error = 0;
-	return -1;
-    }
-    return 0;
-}
-
-static int flush_write_check_error(file_descriptor *desc, int *errp
-#ifdef USE_VM_PROBES
-                                   , dt_private *dt_priv, char *dt_utag
-#endif
-				   ) {
-    int r;
-    if ( (r = flush_write(desc, errp
-#ifdef USE_VM_PROBES
-			  , dt_priv, dt_utag
-#endif
-			  )) != 0) {
-	check_write_error(desc, NULL);
-	return r;
-    } else {
-	return check_write_error(desc, errp);
-    }
-}
-
-static struct t_data *async_lseek(file_descriptor *desc, int *errp, int reply,
-				  Sint64 offset, int origin
-#ifdef USE_VM_PROBES
-				  , Sint64 *dt_i1, Sint64 *dt_i2, Sint64 *dt_i3
-#endif
-				  ) {
-    struct t_data *d;
-    if (! (d = EF_ALLOC(sizeof(struct t_data)))) {
-	*errp = ENOMEM;
-	return NULL;
-    }
-    d->flags = desc->flags;
-    d->fd = desc->fd;
-    d->command = FILE_LSEEK;
-    d->reply = reply;
-    d->c.lseek.offset = offset;
-    d->c.lseek.origin = origin;
-#ifdef USE_VM_PROBES
-    if (dt_i1 != NULL) {
-        *dt_i1 = d->fd;
-        *dt_i2 = d->c.lseek.offset;
-        *dt_i3 = d->c.lseek.origin;
-    }
-#endif
-    d->invoke = invoke_lseek;
-    d->free = free_data;
-    d->level = 1;
-    cq_enq(desc, d);
-    return d;
-}
-
-static void flush_read(file_descriptor *desc) {
-    desc->read_offset = 0;
-    desc->read_size = 0;
-    if (desc->read_binp) {
-	driver_free_binary(desc->read_binp);
-	desc->read_binp = NULL;
-    }
-}
-
-static int lseek_flush_read(file_descriptor *desc, int *errp
-#ifdef USE_VM_PROBES
-			    ,dt_private *dt_priv, char *dt_utag
-#endif
-			    ) {
-    int r = 0;
-    size_t read_size = desc->read_size;
-#ifdef USE_VM_PROBES
-    Sint64 dt_i1 = 0, dt_i2 = 0, dt_i3 = 0;
-#endif
-    struct t_data *d;
-
-    flush_read(desc);
-    if (read_size != 0) {
-	if ((d = async_lseek(desc, errp, 0,
-                             -((ssize_t)read_size), EFILE_SEEK_CUR
-#ifdef USE_VM_PROBES
-			     , &dt_i1, &dt_i2, &dt_i3
-#endif
-			     )) == NULL) {
-            r = -1;
-        } else {
-#ifdef USE_VM_PROBES
-            d->sched_i1 = dt_priv->thread_num;
-            d->sched_i2 = dt_priv->tag;
-            d->sched_utag[0] = '\0';
-            if (dt_utag != NULL) {
-                if (dt_utag[0] == '\0') {
-                    dt_utag = NULL;
-                } else {
-                    strncpy(d->sched_utag, dt_utag, sizeof(d->sched_utag) - 1);
-                    d->sched_utag[sizeof(d->sched_utag) - 1] = '\0';
-                }
-            }
-            DTRACE11(efile_drv_entry, dt_priv->thread_num, dt_priv->tag++,
-                     dt_utag, FILE_LSEEK,
-                     NULL, NULL, dt_i1, dt_i2, dt_i3, 0, desc->port_str);
-#endif /* USE_VM_PROBES */
-        }
-    }
-    return r;
-}
-
-
-/*********************************************************************
- * Driver entry point -> stop
- * The close has to be scheduled on async thread, so that currently active
- * async operation does not suddenly have the ground disappearing under their feet...
- */
-static void 
-file_stop(ErlDrvData e)
-{
-    file_descriptor* desc = (file_descriptor*)e;
-
-    TRACE_C('p');
-
-    IF_THRDS {
-	flush_read(desc);
-	if (desc->fd != FILE_FD_INVALID) {
-	    struct t_data *d = EF_SAFE_ALLOC(sizeof(struct t_data));
-	    d->command = FILE_CLOSE_ON_PORT_EXIT;
-	    d->reply = !0;
-	    d->fd = desc->fd;
-	    d->flags = desc->flags;
-	    d->invoke = invoke_close;
-	    d->free = free_data;
-	    d->level = 2;
-	    d->data_to_free = (void *) desc;
-	    cq_enq(desc, d);
-	    desc->fd = FILE_FD_INVALID;
-	    desc->flags = 0;
-	    cq_execute(desc);
-	} else {
-	    EF_FREE(desc);
-	}
-    } else {
-	if (desc->fd != FILE_FD_INVALID) {
-	    do_close(desc->flags, desc->fd);
-	    desc->fd = FILE_FD_INVALID;
-	    desc->flags = 0;
-	}
-	if (desc->read_binp) {
-	    driver_free_binary(desc->read_binp);
-	}
-	EF_FREE(desc);
-    }
-}
-
-/*********************************************************************
- * Driver entry point -> ready_async
- */
-static void 
-file_async_ready(ErlDrvData e, ErlDrvThreadData data)
-{
-    file_descriptor *desc = (file_descriptor*)e;
-    struct t_data *d = (struct t_data *) data;
-    char header[5];		/* result code + count */
-    char resbuf[RESBUFSIZE];	/* Result buffer. */
-#ifdef  USE_VM_PROBES
-    int sched_i1 = d->sched_i1, sched_i2 = d->sched_i2, command = d->command,
-        result_ok = d->result_ok,
-        posix_errno = d->result_ok ? 0 : d->errInfo.posix_errno;
-    DTRACE_CHARBUF(sched_utag, DTRACE_EFILE_BUFSIZ+1);
-
-    sched_utag[0] = '\0';
-    if (DTRACE_ENABLED(efile_drv_return)) {
-        strncpy(sched_utag, d->sched_utag, DTRACE_EFILE_BUFSIZ);
-        sched_utag[DTRACE_EFILE_BUFSIZ] = '\0';
-    }
-#endif  /* USE_VM_PROBES */
-
-    TRACE_C('r');
-
-    if (try_again(desc, d)) {
-        /* DTRACE TODO: what kind of probe makes sense here? */
-	return;
-    }
-
-    switch (d->command)
-    {
-    case FILE_READ:
-	if (!d->result_ok) {
-	    reply_error(desc, &d->errInfo);
-	} else {
-	    size_t available_bytes = 
-		d->c.read.bin_offset + d->c.read.bin_size - desc->read_offset;
-	    if (available_bytes < d->c.read.size) {
-		d->c.read.size = available_bytes;
-	    }
-	    TRACE_C('D');
-	    reply_data(desc, d->c.read.binp, 
-		       desc->read_offset, d->c.read.size);
-	    desc->read_offset += d->c.read.size;
-	    desc->read_size = 
-		d->c.read.bin_offset + d->c.read.bin_size - desc->read_offset;
-	    try_free_read_bin(desc);
-	}
-	free_read(data);
-	break;
-      case FILE_READ_LINE:
-	  /* The read_line structure differs from the read structure.
-	     The data->read_offset and d->c.read_line.read_offset are copies, as are
-	     data->read_size and d->c.read_line.read_size
-             The read_line function does not kniow in advance how large the binary has to be,
-	     why new allocation (but not reallocation of the old binary, for obvious reasons) 
-	     may happen in the worker thread. */
-	if (!d->result_ok) {
-	    reply_error(desc, &d->errInfo);
-	} else {
-	    size_t len = d->c.read_line.nl_pos - d->c.read_line.read_offset;
-	    TRACE_C('L');
-	    reply_data(desc, d->c.read_line.binp, 
-		       d->c.read_line.read_offset, len);
-	    desc->read_offset = d->c.read_line.read_offset + d->c.read_line.nl_skip + len;
-	    desc->read_size = 
-		d->c.read_line.read_size - d->c.read_line.nl_skip - len;
-	    if (desc->read_binp != d->c.read_line.binp) { /* New binary allocated */
-		driver_free_binary(desc->read_binp);
-		desc->read_binp =  d->c.read_line.binp;
-		driver_binary_inc_refc(desc->read_binp);
-	    }
-#if !ALWAYS_READ_LINE_AHEAD
-	    ASSERT(desc->read_bufsize > 0 || desc->read_size == 0);
-	    if (desc->read_bufsize == 0) {
-		desc->read_offset = desc->read_binp->orig_size; /* triggers cleanup */
-	    }
-#endif
-	    try_free_read_bin(desc);
-	}
-	free_read_line(data);
-	break;
-      case FILE_READ_FILE:
-	if (!d->result_ok)
-	    reply_error(desc, &d->errInfo);
-	else {
-	    header[0] = FILE_RESP_ALL_DATA;
-	    TRACE_C('R');
-	    driver_output_binary(desc->port, header, 1,
-				 d->c.read_file.binp,
-				 0, d->c.read_file.offset);
-	}
-	free_read_file(data);
-	break;
-      case FILE_WRITE:
-	  if (d->reply) {
-	      if (! d->result_ok) {
-		  reply_error(desc, &d->errInfo);
-	      } else {
-		  reply_Uint(desc, d->c.writev.reply_size);
-	      }
-	  } else {
-	      if (! d->result_ok) {
-		  desc->write_error = !0;
-		  desc->write_errInfo = d->errInfo;
-	      }
-	  }
-	  free_data(data);
-	  break;
-      case FILE_LSEEK:
-	  if (d->reply) {
-	      if (d->result_ok)
-		  reply_Sint64(desc, d->c.lseek.location);
-	      else
-		  reply_error(desc, &d->errInfo);
-	  }
-	  free_data(data);
-	  break;
-      case FILE_MKDIR:
-      case FILE_RMDIR:
-      case FILE_CHDIR:
-      case FILE_DELETE:
-      case FILE_FDATASYNC:
-      case FILE_FSYNC:
-      case FILE_TRUNCATE:
-      case FILE_LINK:
-      case FILE_SYMLINK:
-      case FILE_RENAME:
-      case FILE_WRITE_INFO:
-      case FILE_FADVISE:
-      case FILE_FALLOCATE:
-	reply(desc, d->result_ok, &d->errInfo);
-	free_data(data);
-	break;
-      case FILE_ALTNAME:
-      case FILE_PWD:
-      case FILE_READLINK:
-        {
-	    int length;
-	    char *resbuf = d->b;
-
-	    if (!d->result_ok)
-		reply_error(desc, &d->errInfo);
-	    else {
-		resbuf[0] = FILE_RESP_FNAME;
-		length = 1+FILENAME_BYTELEN((char*) resbuf+1);
-		TRACE_C('R');
-		driver_output2(desc->port, resbuf, 1, resbuf+1, length-1);
-	    }
-	    free_data(data);
-	    break;
-	}
-      case FILE_OPEN:
-	if (!d->result_ok) {
-	    reply_error(desc, &d->errInfo);
-	} else {
-	    ASSERT(d->is_fd_unused);
-	    desc->fd = d->fd;
-	    desc->flags = d->flags;
-	    d->is_fd_unused = 0;
-	    reply_Uint(desc, d->fd);
-	}
-	free_data(data);
-	break;
-      case FILE_FSTAT:
-      case FILE_LSTAT:
-        {
-	    if (d->result_ok) {
-		resbuf[0] = FILE_RESP_INFO;
-
-		put_int32(d->info.size_high,         &resbuf[1 + ( 0 * 4)]);
-		put_int32(d->info.size_low,          &resbuf[1 + ( 1 * 4)]);
-		put_int32(d->info.type,              &resbuf[1 + ( 2 * 4)]);
-
-		/* Note 64 bit indexing in resbuf here */
-		put_int64(d->info.accessTime,        &resbuf[1 + ( 3 * 4)]);
-		put_int64(d->info.modifyTime,        &resbuf[1 + ( 5 * 4)]);
-		put_int64(d->info.cTime,             &resbuf[1 + ( 7 * 4)]);
-
-		put_int32(d->info.mode,              &resbuf[1 + ( 9 * 4)]);
-		put_int32(d->info.links,             &resbuf[1 + (10 * 4)]);
-		put_int32(d->info.major_device,      &resbuf[1 + (11 * 4)]);
-		put_int32(d->info.minor_device,      &resbuf[1 + (12 * 4)]);
-		put_int32(d->info.inode,             &resbuf[1 + (13 * 4)]);
-		put_int32(d->info.uid,               &resbuf[1 + (14 * 4)]);
-		put_int32(d->info.gid,               &resbuf[1 + (15 * 4)]);
-		put_int32(d->info.access,            &resbuf[1 + (16 * 4)]);
-
-#define RESULT_SIZE (1 + (17 * 4))
-		TRACE_C('R');
-		driver_output2(desc->port, resbuf, RESULT_SIZE, NULL, 0);
-#undef RESULT_SIZE
-	    } else
-		reply_error(desc, &d->errInfo);
-	}
-	free_data(data);
-	break;
-      case FILE_READDIR:
-	if (!d->result_ok) {
-	    reply_error(desc, &d->errInfo);
-	} else {
-	    struct t_readdir_buf *b1 = d->c.read_dir.first_buf;
-	    char   op = FILE_RESP_LFNAME;
-
-	    TRACE_C('R');
-	    ASSERT(b1);
-
-	    while (b1) {
-		struct t_readdir_buf *b2 = b1;
-		char *p = &b1->buf[0];
-		driver_output2(desc->port, p, 1, p + 1, b1->n - 1);
-		b1 = b1->next;
-		EF_FREE(b2);
-	    }
-	    driver_output2(desc->port, &op, 1, NULL, 0);
-    
-	    d->c.read_dir.first_buf = NULL;
-	    d->c.read_dir.last_buf = NULL;
-	}
-	free_readdir(data);
-	break;
-      case FILE_CLOSE:
-	  if (d->reply) {
-	      TRACE_C('K');
-	      reply_ok(desc);
-#ifdef USE_VM_PROBES
-              result_ok = 1;
-#endif
-	  }
-	  free_data(data);
-	  break;
-      case FILE_PWRITEV:
-	  if (!d->result_ok) {
-	      reply_Uint_error(desc, d->c.pwritev.cnt, &d->errInfo);
-	  } else {
-	      reply_Uint(desc, d->c.pwritev.n);
-	  }
-	  free_data(data);
-	  break;
-      case FILE_PREADV:
-	  if (!d->result_ok) {
-	      reply_error(desc, &d->errInfo);
-	  } else {
-	      reply_ev(desc, FILE_RESP_LDATA, &d->c.preadv.eiov);
-	  }
-	  free_preadv(data);
-	  break;
-      case FILE_IPREAD:
-	  if (!d->result_ok) {
-	      reply_error(desc, &d->errInfo);
-	  } else if (!d->c.preadv.eiov.vsize) {
-	      reply_eof(desc);
-	  } else {
-	      reply_ev(desc, FILE_RESP_N2DATA, &d->c.preadv.eiov);
-	  }
-	  free_preadv(data);
-	  break;
-#ifdef HAVE_SENDFILE
-      case FILE_SENDFILE:
-	  if (d->result_ok == -1) {
-	      if (d->errInfo.posix_errno == ECONNRESET ||
-		  d->errInfo.posix_errno == ENOTCONN ||
-		  d->errInfo.posix_errno == EPIPE)
-		  reply_string_error(desc,"closed");
-	      else
-		  reply_error(desc, &d->errInfo);
-	      desc->sendfile_state = not_sending;
-	      free_sendfile(data);
-	  } else if (d->result_ok == 0) {
-	      reply_Sint64(desc, d->c.sendfile.written);
-	      desc->sendfile_state = not_sending;
-	      free_sendfile(data);
-	  } else if (d->result_ok == 1) { /* If we are using select to send the rest of the data */
-	      desc->sendfile_state = sending;
-	      desc->d = d;
-	      driver_select(desc->port, (ErlDrvEvent)(long)d->c.sendfile.out_fd,
-			    ERL_DRV_USE|ERL_DRV_WRITE, 1);
-	  }
-	  break;
-#endif
-      case FILE_CLOSE_ON_PORT_EXIT:
-	  /* See file_stop. However this is never invoked after the port is killed. */
-	  free_data(data);
-	  desc = NULL;
-	  /* This is it for this port, so just send dtrace and return, avoid doing anything to the freed data */
-	  DTRACE6(efile_drv_return, sched_i1, sched_i2, sched_utag,
-		  command, result_ok, posix_errno);
-	  return;
-      default:
-	abort();
-    }
-    DTRACE6(efile_drv_return, sched_i1, sched_i2, sched_utag,
-            command, result_ok, posix_errno);
-    if (desc->write_buffered != 0 && desc->timer_state == timer_idle ) {
-	desc->timer_state = timer_write;
-	driver_set_timer(desc->port, desc->write_delay);
-    }
-    cq_execute(desc);
-
-}
-
-
-/*********************************************************************
- * Driver entry point -> output
- */
-static void 
-file_output(ErlDrvData e, char* buf, ErlDrvSizeT count)
-{
-    file_descriptor* desc = (file_descriptor*)e;
-    Efile_error errInfo;	/* The error codes for the last operation. */
-    Sint fd;			/* The file descriptor for this port, if any,
-				 * -1 if none.
-				 */
-    char* name;			/* Points to the filename in buf. */
-    int command;
-    struct t_data *d = NULL;
-#ifdef  USE_VM_PROBES
-    char *dt_utag = NULL;
-    char *dt_s1 = NULL, *dt_s2 = NULL;
-    Sint64 dt_i1 = 0;
-    Sint64 dt_i2 = 0;
-    Sint64 dt_i3 = 0;
-    Sint64 dt_i4 = 0;
-    dt_private *dt_priv = get_dt_private(0);
-#endif  /* USE_VM_PROBES */
-
-    TRACE_C('o');
-
-    fd  = desc->fd;
-    name = buf+1;
-    command = *(uchar*)buf++;
-
-    switch(command) {
-
-    case FILE_MKDIR:
-    {
-	d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1 + FILENAME_BYTELEN(name) + FILENAME_CHARSIZE);
-	
-	FILENAME_COPY(d->b, name);
-#ifdef USE_VM_PROBES
-	dt_s1 = d->b;
-	dt_utag = name + FILENAME_BYTELEN(name) + FILENAME_CHARSIZE;
-#endif
-	d->command = command;
-	d->invoke = invoke_mkdir;
-	d->free = free_data;
-	d->level = 2;
-	goto done;
-    }
-    case FILE_RMDIR:
-    {
-	d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1 + FILENAME_BYTELEN(name) + FILENAME_CHARSIZE);
-	
-	FILENAME_COPY(d->b, name);
-#ifdef USE_VM_PROBES
-	dt_s1 = d->b;
-	dt_utag = name + FILENAME_BYTELEN(name) + FILENAME_CHARSIZE;
-#endif
-	d->command = command;
-	d->invoke = invoke_rmdir;
-	d->free = free_data;
-	d->level = 2;
-	goto done;
-    }
-    case FILE_DELETE:
-    {
-	d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1 + FILENAME_BYTELEN(name) + FILENAME_CHARSIZE);
-	
-	FILENAME_COPY(d->b, name);
-#ifdef USE_VM_PROBES
-	dt_s1 = d->b;
-	dt_utag = name + FILENAME_BYTELEN(name) + FILENAME_CHARSIZE;
-#endif
-	d->command = command;
-	d->invoke = invoke_delete_file;
-	d->free = free_data;
-	d->level = 2;
-	goto done;
-    }
-    case FILE_RENAME:
-	{
-	    char* new_name;
-	    int namelen = FILENAME_BYTELEN(name)+FILENAME_CHARSIZE;
-	    new_name = name+namelen;
-	    d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1
-			      + namelen
-			      + FILENAME_BYTELEN(new_name) + FILENAME_CHARSIZE);
-	
-	    FILENAME_COPY(d->b, name);
-	    FILENAME_COPY(d->b + namelen, new_name);
-#ifdef USE_VM_PROBES
-	    dt_s1 = d->b;
-	    dt_s2 = d->b + namelen;
-	    dt_utag = buf + namelen + FILENAME_BYTELEN(new_name) + FILENAME_CHARSIZE;
-#endif
-	    d->flags = desc->flags;
-	    d->fd = fd;
-	    d->command = command;
-	    d->invoke = invoke_rename;
-	    d->free = free_data;
-	    d->level = 2;
-	    goto done;
-	}
-    case FILE_CHDIR:
-    {
-	d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1 + FILENAME_BYTELEN(name) + FILENAME_CHARSIZE);
-	
-	FILENAME_COPY(d->b, name);
-#ifdef USE_VM_PROBES
-	dt_s1 = d->b;
-	dt_utag = name + FILENAME_BYTELEN(name) + FILENAME_CHARSIZE;
-#endif
-	d->command = command;
-	d->invoke = invoke_chdir;
-	d->free = free_data;
-	d->level = 2;
-	goto done;
-    }
-    case FILE_PWD:
-        {
-	    d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1 + RESBUFSIZE + 1);
-	
-	    d->drive = *(uchar*)buf;
-#ifdef USE_VM_PROBES
-	    dt_utag = buf + 1;
-#endif
-	    d->command = command;
-	    d->invoke = invoke_pwd;
-	    d->free = free_data;
-	    d->level = 2;
-	    goto done;
-	}
-
-    case FILE_READDIR: 
-#ifdef USE_THREADS
-	if (sys_info.async_threads > 0)
-	{
-	    d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1 + FILENAME_BYTELEN(name) + 
-			      FILENAME_CHARSIZE);
-	
-	    FILENAME_COPY(d->b, name);
-#ifdef USE_VM_PROBES
-	    dt_s1 = d->b;
-	    dt_utag = name + FILENAME_BYTELEN(name) + FILENAME_CHARSIZE;
-#endif
-	    d->dir_handle = NULL;
-	    d->command = command;
-	    d->invoke = invoke_readdir;
-	    d->free = free_readdir;
-	    d->level = 2;
-	    d->c.read_dir.first_buf = NULL;
-	    d->c.read_dir.last_buf = NULL;
-	    goto done;
-	}
-	else   
-#endif
-	{
-	    size_t resbufsize;
-	    size_t n = 0, total = 0;
-	    int res = 0;
-	    char resbuf[READDIR_BUFSIZE];
-
-	    EFILE_DIR_HANDLE dir_handle; /* Handle to open directory. */
-
-	    total               = READDIR_BUFSIZE;
-	    errInfo.posix_errno = 0;
-	    dir_handle          = NULL;
-	    resbuf[0]           = FILE_RESP_LFNAME;
-
-#ifdef USE_VM_PROBES
-	    dt_s1 = name;
-	    dt_utag = name + FILENAME_BYTELEN(name) + FILENAME_CHARSIZE;
-#endif
-	    /* Fill the buffer with multiple directory listings before sending it to the
-	     * receiving process. READDIR_CHUNKS is minimum number of files sent to the
-	     * receiver.
-	     * Format for each driver_output2:
-	     * ------------------------------------
-	     * | Type   | Len     | Filename  | ...
-	     * | 1 byte | 2 bytes | Len bytes | ...
-	     * ------------------------------------
-	     */
-
-	    do {
-		n = 1;
-		resbufsize = READDIR_BUFSIZE - n;
-
-		do {
-		    res = efile_readdir(&errInfo, name, &dir_handle, resbuf + n + 2, &resbufsize);
-
-		    if (res) {
-			put_int16((Uint16)resbufsize, resbuf + n);
-			n += 2 + resbufsize;
-			resbufsize = READDIR_BUFSIZE - n;
-		    }
-		} while( res && ((total - n - 2) >= MAXPATHLEN*FILENAME_CHARSIZE));
-
-		if (n > 1) {
-		    driver_output2(desc->port, resbuf, 1, resbuf + 1, n - 1);
-		}
-	    } while(res);
-
-	    if (errInfo.posix_errno != 0) {
-		reply_error(desc, &errInfo);
-		return;
-	    }
-#ifdef USE_VM_PROBES
-	    if (dt_utag != NULL && dt_utag[0] == '\0') {
-                dt_utag = NULL;
-            } 
-
-	    DTRACE11(efile_drv_entry, dt_priv->thread_num, dt_priv->tag,
-		     dt_utag, command, name, dt_s2,
-		     dt_i1, dt_i2, dt_i3, dt_i4, desc->port_str);
-	    DTRACE6(efile_drv_return, dt_priv->thread_num, dt_priv->tag++, 
-		    dt_utag, command, 1, 0);
-#endif
-	    TRACE_C('R');
-	    driver_output2(desc->port, resbuf, 1, NULL, 0);
-	    return;
-	}
-    case FILE_OPEN:
-	{
-	    d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1 + FILENAME_BYTELEN(buf+4) + 
-			      FILENAME_CHARSIZE);
-	
-	    d->flags = get_int32((uchar*)buf);
-	    name = buf+4;
-	    FILENAME_COPY(d->b, name);
-#ifdef USE_VM_PROBES
-	    dt_i1 = d->flags;
-	    dt_s1 = d->b;
-	    dt_utag = name + FILENAME_BYTELEN(d->b) + FILENAME_CHARSIZE;
-#endif
-	    d->command = command;
-	    d->invoke = invoke_open;
-	    d->free = free_data;
-	    d->level = 2;
-	    d->is_fd_unused = 1;
-	    goto done;
-	}
-
-    case FILE_FDATASYNC:
-	{
-	    d = EF_SAFE_ALLOC(sizeof(struct t_data));
-	    
-	    d->fd = fd;
-#ifdef USE_VM_PROBES
-	    dt_utag = name;
-	    dt_i1 = fd;
-#endif
-	    d->command = command;
-	    d->invoke = invoke_fdatasync;
-	    d->free = free_data;
-	    d->level = 2;
-	    goto done;
-	}
-
-    case FILE_FSYNC:
-	{
-	    d = EF_SAFE_ALLOC(sizeof(struct t_data));
-	    
-	    d->fd = fd;
-#ifdef USE_VM_PROBES
-	    dt_utag = name;
-	    dt_i1 = fd;
-#endif
-	    d->command = command;
-	    d->invoke = invoke_fsync;
-	    d->free = free_data;
-	    d->level = 2;
-	    goto done;
-	}
-
-
-    case FILE_FSTAT: 
-    case FILE_LSTAT:
-	{
-	    d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1 + FILENAME_BYTELEN(name) + 
-			      FILENAME_CHARSIZE);
-	    
-	    FILENAME_COPY(d->b, name);
-	    d->fd = fd;
-#ifdef USE_VM_PROBES
-	    dt_utag = name + FILENAME_BYTELEN(d->b) + FILENAME_CHARSIZE;
-	    if (command == FILE_LSTAT) {
-		dt_s1 = d->b;
-	    } else {
-		dt_i1 = fd;
-	    }
-#endif
-	    d->command = command;
-	    d->invoke = invoke_flstat;
-	    d->free = free_data;
-	    d->level = 2;
-	    goto done;
-	}
-	
-    case FILE_TRUNCATE:
-        {
-	    d = EF_SAFE_ALLOC(sizeof(struct t_data));
-	    
-	    d->flags = desc->flags;
-	    d->fd = fd;
-#ifdef USE_VM_PROBES
-	    dt_utag = name;
-	    dt_i1 = fd;
-	    dt_i2 = d->flags;
-#endif
-	    d->command = command;
-	    d->invoke = invoke_truncate;
-	    d->free = free_data;
-	    d->level = 2;
-	    goto done;
-	}
-
-    case FILE_WRITE_INFO:
-	{
-	    d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1
-			      + FILENAME_BYTELEN(buf + 9*4) + FILENAME_CHARSIZE);
-	    
-	    d->info.mode       = get_int32(buf + 0 * 4);
-	    d->info.uid        = get_int32(buf + 1 * 4);
-	    d->info.gid        = get_int32(buf + 2 * 4);
-	    d->info.accessTime = get_int64(buf + 3 * 4);
-	    d->info.modifyTime = get_int64(buf + 5 * 4);
-	    d->info.cTime      = get_int64(buf + 7 * 4);
-
-	    FILENAME_COPY(d->b, buf + 9*4);
-#ifdef USE_VM_PROBES
-	    dt_i1              = d->info.mode;
-	    dt_i2              = d->info.uid;
-	    dt_i3              = d->info.gid;
-	    dt_s1 = d->b;
-	    dt_utag = buf + 9 * 4 + FILENAME_BYTELEN(d->b) + FILENAME_CHARSIZE;
-#endif
-	    d->command = command;
-	    d->invoke = invoke_write_info;
-	    d->free = free_data;
-	    d->level = 2;
-	    goto done;
-	}
-
-    case FILE_READLINK:
-	{
-	    d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1 + 
-			      MAX(RESBUFSIZE, (FILENAME_BYTELEN(name) +  
-					       FILENAME_CHARSIZE))  + 1);
-	    FILENAME_COPY(d->b, name);
-#ifdef USE_VM_PROBES
-	    dt_s1 = d->b;
-	    dt_utag = name + FILENAME_BYTELEN(d->b) + FILENAME_CHARSIZE;
-#endif
-	    d->command = command;
-	    d->invoke = invoke_readlink;
-	    d->free = free_data;
-	    d->level = 2;
-	    goto done;
-	}
-
-    case FILE_ALTNAME:
-	{
-	     d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1 + 
-			       MAX(RESBUFSIZE, (FILENAME_BYTELEN(name) +  
-						FILENAME_CHARSIZE))  + 1);
-	    FILENAME_COPY(d->b, name);
-#ifdef USE_VM_PROBES
-	    dt_s1 = d->b;
-	    dt_utag = name + FILENAME_BYTELEN(d->b) + FILENAME_CHARSIZE;
-#endif
-	    d->command = command;
-	    d->invoke = invoke_altname;
-	    d->free = free_data;
-	    d->level = 2;
-	    goto done;
-	}
-
-
-    case FILE_LINK:
-	{
-	    char* new_name;
-	    int namelen = FILENAME_BYTELEN(name) + FILENAME_CHARSIZE;
-
-	    new_name = name+namelen;
-	    d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1
-			      + namelen
-			      + FILENAME_BYTELEN(new_name) + FILENAME_CHARSIZE);
-	
-	    FILENAME_COPY(d->b, name);
-	    FILENAME_COPY(d->b + namelen, new_name);
-#ifdef USE_VM_PROBES
-	    dt_s1 = d->b;
-	    dt_s2 = d->b + namelen;
-	    dt_utag = buf + namelen + FILENAME_BYTELEN(dt_s2) + FILENAME_CHARSIZE;
-#endif
-	    d->flags = desc->flags;
-	    d->fd = fd;
-	    d->command = command;
-	    d->invoke = invoke_link;
-	    d->free = free_data;
-	    d->level = 2;
-	    goto done;
-	}
-
-    case FILE_SYMLINK:
-	{
-	    char* new_name;
-	    int namelen = FILENAME_BYTELEN(name) + FILENAME_CHARSIZE;
-
-	    new_name = name+namelen;
-	    d = EF_SAFE_ALLOC(sizeof(struct t_data) - 1
-			      + namelen
-			      + FILENAME_BYTELEN(new_name) + FILENAME_CHARSIZE);
-	
-	    FILENAME_COPY(d->b, name);
-	    FILENAME_COPY(d->b + namelen, new_name);
-#ifdef USE_VM_PROBES
-	    dt_s1 = d->b;
-	    dt_s2 = d->b + namelen;
-	    dt_utag = buf + namelen + FILENAME_BYTELEN(dt_s2) + FILENAME_CHARSIZE;
-#endif
-	    d->flags = desc->flags;
-	    d->fd = fd;
-	    d->command = command;
-	    d->invoke = invoke_symlink;
-	    d->free = free_data;
-	    d->level = 2;
-	    goto done;
-	}
-
-    case FILE_FADVISE:
-    {
-        d = EF_SAFE_ALLOC(sizeof(struct t_data));
-
-        d->fd = fd;
-        d->command = command;
-        d->invoke = invoke_fadvise;
-        d->free = free_data;
-        d->level = 2;
-        d->c.fadvise.offset = get_int64((uchar*) buf);
-        d->c.fadvise.length = get_int64(((uchar*) buf) + sizeof(Sint64));
-        d->c.fadvise.advise = get_int32(((uchar*) buf) + 2 * sizeof(Sint64));
-#ifdef USE_VM_PROBES
-        dt_i1 = d->fd;
-        dt_i2 = d->c.fadvise.offset;
-        dt_i3 = d->c.fadvise.length;
-        dt_i4 = d->c.fadvise.advise;
-        dt_utag = buf + 3 * sizeof(Sint64);
-#endif
-        goto done;
-    }
-
-    case FILE_FALLOCATE:
-    {
-        d = EF_SAFE_ALLOC(sizeof(struct t_data));
-
-        d->fd = fd;
-        d->command = command;
-        d->invoke = invoke_fallocate;
-        d->free = free_data;
-        d->level = 2;
-        d->c.fallocate.offset = get_int64((uchar*) buf);
-        d->c.fallocate.length = get_int64(((uchar*) buf) + sizeof(Sint64));
-        goto done;
-    }
-
-    }
-
-    /*
-     * Ignore anything else -- let the caller hang.
-     */
-     
-    return;
-
- done:
-    if (d) {
-#ifdef USE_VM_PROBES
-	d->sched_i1 = dt_priv->thread_num;
-	d->sched_i2 = dt_priv->tag;
-	d->sched_utag[0] = '\0';
-	if (dt_utag != NULL) {
-	    if (dt_utag[0] == '\0') {
-		dt_utag = NULL;
-	    } else {
-		strncpy(d->sched_utag, dt_utag, sizeof(d->sched_utag) - 1);
-		d->sched_utag[sizeof(d->sched_utag) - 1] = '\0';
-	    }
-	}
-	DTRACE11(efile_drv_entry, dt_priv->thread_num, dt_priv->tag++,
-		 dt_utag, command, dt_s1, dt_s2,
-		 dt_i1, dt_i2, dt_i3, dt_i4, desc->port_str);
-#endif
-	cq_enq(desc, d);
-    }
-}
-
-/*********************************************************************
- * Driver entry point -> flush
- */
-static void 
-file_flush(ErlDrvData e) {
-    file_descriptor *desc = (file_descriptor *)e;
-#ifdef DEBUG
-    int r;
-#endif
-#ifdef  USE_VM_PROBES
-    dt_private *dt_priv = get_dt_private(dt_driver_io_worker_base);
-#endif
-
-    TRACE_C('f');
-
-#ifdef HAVE_SENDFILE
-    flush_sendfile(desc, NULL);
-#endif
-
-#ifdef DEBUG
-    r = 
-#endif
-         flush_write(desc, NULL
-#ifdef USE_VM_PROBES
-		     , dt_priv, (desc->d == NULL) ? NULL : desc->d->sched_utag
-#endif
-		     );
-    /* Only possible reason for bad return value is ENOMEM, and 
-     * there is nobody to tell...
-     */
-#ifdef DEBUG
-    ASSERT(r == 0); 
-#endif
-    cq_execute(desc);
-}
-
-
-
-/*********************************************************************
- * Driver entry point -> control
- * Only debug functionality...
- */
-static ErlDrvSSizeT
-file_control(ErlDrvData e, unsigned int command, 
-	     char* buf, ErlDrvSizeT len, char **rbuf, ErlDrvSizeT rlen) {
-    file_descriptor *desc = (file_descriptor *)e;
-    switch (command) {
-    case 'K' :
-	if (rlen < 4) {
-	    *rbuf = EF_ALLOC(4);
-	}
-	(*rbuf)[0] = ((desc->key) >> 24) & 0xFF;
-	(*rbuf)[1] = ((desc->key) >> 16) & 0xFF;
-	(*rbuf)[2] = ((desc->key) >> 8) & 0xFF;
-	(*rbuf)[3] = (desc->key) & 0xFF;
-	return 4;
-    default:
-	return 0;
-    }
-}
-
-/*********************************************************************
- * Driver entry point -> timeout
- */
-static void 
-file_timeout(ErlDrvData e) {
-    file_descriptor *desc = (file_descriptor *)e;
-    enum e_timer timer_state = desc->timer_state;
-#ifdef  USE_VM_PROBES
-    dt_private *dt_priv = get_dt_private(dt_driver_io_worker_base);
-#endif
-
-    TRACE_C('t');
-
-    desc->timer_state = timer_idle;
-    switch (timer_state) {
-    case timer_idle:
-	ASSERT(0);
-	break;
-    case timer_again:
-	ASSERT(desc->invoke);
-	ASSERT(desc->free);
-	driver_async(desc->port, KEY(desc), desc->invoke, desc->d, desc->free);
-	break;
-    case timer_write: {
-#ifdef DEBUG
-	int r = 
-#endif
-	         flush_write(desc, NULL
-#ifdef USE_VM_PROBES
-			     , dt_priv, (desc->d == NULL) ? NULL : desc->d->sched_utag
-#endif
-			     );
-	/* Only possible reason for bad return value is ENOMEM, and 
-	 * there is nobody to tell...
-	 */
-	ASSERT(r == 0); 
-	cq_execute(desc);
-    } break;
-    } /* case */
-}
-
-
-
-/*********************************************************************
- * Driver entry point -> outputv
- */
-static void 
-file_outputv(ErlDrvData e, ErlIOVec *ev) {
-    file_descriptor* desc = (file_descriptor*)e;
-    char command;
-    size_t p, q;
-    int err;
-    struct t_data *d = NULL;
-#ifdef USE_VM_PROBES
-    Sint64 dt_i1 = 0, dt_i2 = 0, dt_i3 = 0;
-    Sint64 dt_i4 = 0;
-    char *dt_utag = NULL;
-    char *dt_s1 = NULL;
-    dt_private *dt_priv = get_dt_private(dt_driver_io_worker_base);
-#endif
-
-    TRACE_C('v');
-
-    p = 0; q = 1;
-    if (! EV_GET_CHAR(ev, &command, &p, &q)) {
-	/* Empty command */
-	reply_posix_error(desc, EINVAL);
-	goto done;
-    }
-    /* 'command' contains the decoded command number,
-     * 'p' and 'q' point out the next byte in the command:
-     * ((char *)ev->iov[q].iov_base) + p;
-     */
-    
-    TRACE_F(("%i", (int) command));
-
-    switch (command) {
-
-    case FILE_CLOSE: {
-#ifdef USE_VM_PROBES
-	dt_utag = EV_CHAR_P(ev, p, q);
-#endif
-	flush_read(desc);
-	if (flush_write_check_error(desc, &err
-#ifdef USE_VM_PROBES
-				    , dt_priv, dt_utag
-#endif
-				    ) < 0) {
-	    reply_posix_error(desc, err);
-	    goto done;
-	}
-	if (desc->fd != FILE_FD_INVALID) {
-	    if (! (d = EF_ALLOC(sizeof(struct t_data)))) {
-		reply_posix_error(desc, ENOMEM);
-	    } else {
-		d->command = command;
-		d->reply = !0;
-		d->fd = desc->fd;
-		d->flags = desc->flags;
-#ifdef USE_VM_PROBES
-		dt_i1 = d->fd;
-		dt_i2 = d->flags;
-#endif
-		d->invoke = invoke_close;
-		d->free = free_data;
-		d->level = 2;
-		cq_enq(desc, d);
-		desc->fd = FILE_FD_INVALID;
-		desc->flags = 0;
-	    }
-	} else {
-	    reply_posix_error(desc, EBADF);
-	}
-    } goto done;
-
-    case FILE_READ: {
-	Uint32 sizeH, sizeL;
-	size_t size, alloc_size;
-
-	if (!EV_GET_UINT32(ev, &sizeH, &p, &q)
-	    || !EV_GET_UINT32(ev, &sizeL, &p, &q)) {
-	    /* Wrong buffer length to contain the read count */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-#ifdef USE_VM_PROBES
-	dt_utag = EV_CHAR_P(ev, p, q);
-#endif
-	if (flush_write_check_error(desc, &err
-#ifdef USE_VM_PROBES
-				    , dt_priv, dt_utag
-#endif
-				    ) < 0) {
-	    reply_posix_error(desc, err);
-	    goto done;
-	}
-#if ALWAYS_READ_LINE_AHEAD
-	if (desc->read_bufsize == 0 && desc->read_binp != NULL && desc->read_size > 0) {
-	    /* We have allocated a buffer for line mode but should not really have a 
-	       read-ahead buffer... */
-	    if (lseek_flush_read(desc, &err
-#ifdef USE_VM_PROBES
-				 , dt_priv, dt_utag
-#endif
-				 ) < 0) {
-		reply_posix_error(desc, err);
-		goto done;
-	    }
-	}
-#endif
-#if SIZEOF_SIZE_T == 4
-	if (sizeH != 0) {
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-	size = sizeL;
-#else
-	size = ((size_t)sizeH << 32) | sizeL;
-#endif
-	if ((desc->fd == FILE_FD_INVALID)
-	    || (! (desc->flags & EFILE_MODE_READ)) ) {
-	    reply_posix_error(desc, EBADF);
-	    goto done;
-	}
-	if (size == 0) {
-	    reply_buf(desc, &command, 0);
-	    goto done;
-	}
-	if (desc->read_size >= size) {
-	    /* We already have all data */
-	    TRACE_C('D');
-	    reply_data(desc, desc->read_binp, desc->read_offset, size);
-	    desc->read_offset += size;
-	    desc->read_size -= size;
-	    try_free_read_bin(desc);
-	    goto done;
-	}
-	/* We may have some of the data 
-	 */
-	/* Justification for the following strange formula:
-	 * If the read request is for such a large block as more than 
-	 * half the buffer size it may lead to a lot of unnecessary copying, 
-	 * since the tail of the old buffer is copied to the head of the
-	 * new, and if the tail is almost half the buffer it is a lot
-	 * to copy. Therefore allocate the exact amount needed in 
-	 * this case, giving no lingering tail. */
-	alloc_size = 
-	    size > (desc->read_bufsize>>1) ? 
-	    size : desc->read_bufsize;
-	if (! desc->read_binp) {
-	    /* Need to allocate a new binary for the result */
-	    if (! (desc->read_binp = driver_alloc_binary(alloc_size))) {
-		reply_posix_error(desc, ENOMEM);
-		goto done;
-	    }
-	} else {
-	    /* We already have a buffer */
-	    if (desc->read_binp->orig_size - desc->read_offset < size) {
-		/* Need to allocate a new binary for the result */
-		ErlDrvBinary *binp;
-		if (! (binp = driver_alloc_binary(alloc_size))) {
-		    reply_posix_error(desc, ENOMEM);
-		    goto done;
-		}
-		/* Move data we already have to the new binary */
-		sys_memcpy(binp->orig_bytes, 
-			   desc->read_binp->orig_bytes + desc->read_offset,
-			   desc->read_size);
-		driver_free_binary(desc->read_binp);
-		desc->read_offset = 0;
-		desc->read_binp = binp;
-	    }
-	} 
-	if (! (d = EF_ALLOC(sizeof(struct t_data)))) {
-	    reply_posix_error(desc, ENOMEM);
-	    goto done;
-	}
-	d->command = command;
-	d->reply = !0;
-	d->fd = desc->fd;
-	d->flags = desc->flags;
-	d->c.read.binp = desc->read_binp;
-	d->c.read.bin_offset = desc->read_offset + desc->read_size;
-	d->c.read.bin_size = desc->read_binp->orig_size - d->c.read.bin_offset;
-	d->c.read.size = size;
-#ifdef USE_VM_PROBES
-	dt_i1 = d->fd;
-	dt_i2 = d->flags;
-	dt_i3 = d->c.read.size;
-#endif
-	driver_binary_inc_refc(d->c.read.binp);
-	d->invoke = invoke_read;
-	d->free = free_read;
-	d->level = 1;
-	cq_enq(desc, d);
-    } goto done; /* case FILE_READ: */
-
-    case FILE_READ_LINE: {
-	/*
-	 * Icky little creature... We do mostly as ordinary file read, but with a few differences.
-	 * 1) We have to scan for proper newline sequence if there is a buffer already, we cannot know 
-	 *    in advance if the buffer contains a whole line without scanning.
-	 * 2) We do not know how large the buffer needs to be in advance. We give a default buffer,
-	 *    but the worker may need to allocate a new one. Freeing the old and rereferencing a newly 
-	 *    allocated binary + dealing with offsets and lengts are done in file_async ready
-	 *    for this OP.
-	 */
-#ifdef USE_VM_PROBES
-	dt_utag = EV_CHAR_P(ev, p, q);
-#endif
-	if (flush_write_check_error(desc, &err
-#ifdef USE_VM_PROBES
-				    , dt_priv, dt_utag
-#endif
-				    ) < 0) {
-	    reply_posix_error(desc, err);
-	    goto done;
-	}
-	if (ev->size != 1
-#ifdef USE_VM_PROBES
-	    + FILENAME_BYTELEN(dt_utag) + FILENAME_CHARSIZE
-#endif
-	    ) {
-	    /* Wrong command length */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-	if ((desc->fd == FILE_FD_INVALID)
-	    || (! (desc->flags & EFILE_MODE_READ)) ) {
-	    reply_posix_error(desc, EBADF);
-	    goto done;
-	}
-	if (desc->read_size > 0) {
-	    /* look for '\n' in what we'we already got */
-	    void *nl_ptr = memchr(desc->read_binp->orig_bytes + desc->read_offset,'\n',desc->read_size);
-	    if (nl_ptr != NULL) {
-		/* If found, we're done */
-		int skip = 0;
-		size_t size = ((char *) nl_ptr) - 
-		    ((char *) (desc->read_binp->orig_bytes + desc->read_offset)) + 1;
-		if (size > 1 &&
-		    *(((char *) nl_ptr) - 1) == '\r') {
-		    *(((char *) nl_ptr) - 1) = '\n';		    
-		    skip = 1;
-		    --size;
-		} 
-		reply_data(desc, desc->read_binp, desc->read_offset, size);
-		desc->read_offset += (size + skip);
-		desc->read_size -= (size + skip);
-		try_free_read_bin(desc);
-		goto done;
-	    }
-	}
-	/* Now, it's up to the thread to work out the need for more buffers and such, it's
-	   no use doing it in this thread as we do not have the information required anyway. 
-	   Even a NULL buffer could be handled by the thread, but code is simplified by us 
-	   allocating it */
-	if (! desc->read_binp) {
-	    int alloc_size = (desc->read_bufsize > DEFAULT_LINEBUF_SIZE) ? desc->read_bufsize : 
-		DEFAULT_LINEBUF_SIZE;
-	    /* Allocate a new binary for the result */
-	    if (! (desc->read_binp = driver_alloc_binary(alloc_size))) {
-		reply_posix_error(desc, ENOMEM);
-		goto done;
-	    }
-	}	
-	if (! (d = EF_ALLOC(sizeof(struct t_data)))) {
-	    reply_posix_error(desc, ENOMEM);
-	    goto done;
-	}
-
-	d->command = command;
-	d->reply = !0;
-	d->fd = desc->fd;
-	d->flags = desc->flags;
-	d->c.read_line.binp = desc->read_binp;
-	d->c.read_line.read_offset = desc->read_offset;
-	d->c.read_line.read_size = desc->read_size;
-#ifdef USE_VM_PROBES
-	dt_i1 = d->fd;
-	dt_i2 = d->flags;
-	dt_i3 = d->c.read_line.read_offset;
-#endif
-#if !ALWAYS_READ_LINE_AHEAD
-	d->c.read_line.read_ahead = (desc->read_bufsize > 0);
-#ifdef USE_VM_PROBES
-	dt_i4 = d->c.read_line.read_ahead;
-#endif
-#endif 
-	driver_binary_inc_refc(d->c.read.binp);
-	d->invoke = invoke_read_line;
-	d->free = free_read_line;
-	d->level = 1;
-	cq_enq(desc, d);
-    } goto done;
-    case FILE_WRITE: { /* Dtrace: The dtrace user tag is not last in message, 
-			  but follows the message tag directly. 
-			  This is handled specially in prim_file.erl */
-	ErlDrvSizeT skip = 1;
-	ErlDrvSizeT size = ev->size - skip;
-
-#ifdef USE_VM_PROBES
-	dt_utag = EV_CHAR_P(ev, p, q);
-	skip += FILENAME_BYTELEN(dt_utag) + FILENAME_CHARSIZE;
-	size = ev->size - skip;
-#endif
-	if (lseek_flush_read(desc, &err
-#ifdef USE_VM_PROBES
-			     , dt_priv, dt_utag
-#endif
-			     ) < 0) {
-	    reply_posix_error(desc, err);
-	    goto done;
-	}
-	if (! (desc->flags & EFILE_MODE_WRITE)) {
-	    reply_posix_error(desc, EBADF);
-	    goto done;
-	}
-	if (size == 0) {
-	    reply_Uint(desc, size);
-	    goto done;
-	}
-	MUTEX_LOCK(desc->q_mtx);
-	if (driver_enqv(desc->port, ev, skip)) {
-	    MUTEX_UNLOCK(desc->q_mtx);
-	    reply_posix_error(desc, ENOMEM);
-	    goto done;
-	}
-	desc->write_buffered += size;
-	if (desc->write_buffered < desc->write_bufsize) {
-	    MUTEX_UNLOCK(desc->q_mtx);
-	    reply_Uint(desc, size);
-	    if (desc->timer_state == timer_idle) {
-		desc->timer_state = timer_write;
-		driver_set_timer(desc->port, desc->write_delay);
-	    }
-	} else {
-	    if ((d = async_write(desc, &err, !0, size
-#ifdef USE_VM_PROBES
-				 , &dt_i1, &dt_i2, &dt_i3
-#endif
-				 )) == NULL) {
-		MUTEX_UNLOCK(desc->q_mtx);
-		reply_posix_error(desc, err);
-		goto done;
-	    } else {
-		MUTEX_UNLOCK(desc->q_mtx);
-	    }
-	}
-    } goto done; /* case FILE_WRITE */
-
-    case FILE_PWRITEV: { /* Dtrace: The dtrace user tag is not last in message, 
-			   but follows the message tag directly. 
-			   This is handled specially in prim_file.erl */
-	Uint32 i, j, n; 
-	size_t total;
-#ifdef USE_VM_PROBES
-	char dt_tmp;
-	int dt_utag_bytes = 1;
-
-	dt_utag = EV_CHAR_P(ev, p, q);
-	/* This will work for UTF-8, but not for UTF-16 - extra reminder here */
-#ifdef FILENAMES_16BIT 
-#error 16bit characters in filenames and dtrace in combination is not supported.
-#endif
-	while (EV_GET_CHAR(ev, &dt_tmp, &p, &q) && dt_tmp != '\0') {
-	    dt_utag_bytes++;
-	}
-#endif
-	if (ev->size < 1+4
-#ifdef USE_VM_PROBES
-	    + dt_utag_bytes
-#endif
-	    || !EV_GET_UINT32(ev, &n, &p, &q)) {
-	    /* Buffer too short to contain even the number of pos/size specs */
-	    reply_Uint_posix_error(desc, 0, EINVAL);
-	    goto done;
-	}
-	if (lseek_flush_read(desc, &err
-#ifdef USE_VM_PROBES
-			     , dt_priv, dt_utag
-#endif
-			     ) < 0) {
-	    reply_Uint_posix_error(desc, 0, err);
-	    goto done;
-	}
-	if (flush_write_check_error(desc, &err
-#ifdef USE_VM_PROBES
-				    , dt_priv, dt_utag
-#endif
-				    ) < 0) {
-	    reply_Uint_posix_error(desc, 0, err);
-	    goto done;
-	}
-	if (n == 0) {
-	    /* Trivial case - nothing to write */
-	    if (ev->size != 1+4) {
-		reply_posix_error(desc, err);
-	    } else {
-		reply_Uint(desc, 0);
-	    }
-	    goto done;
-	}
-	if (ev->size < 1+4+8*(2*n)
-#ifdef USE_VM_PROBES
-	    + dt_utag_bytes
-#endif
-	    ) {
-	    /* Buffer too short to contain even the pos/size specs */
-	    reply_Uint_posix_error(desc, 0, EINVAL);
-	    goto done;
-	}
-	d = EF_ALLOC(sizeof(struct t_data) 
-		     + (n * sizeof(struct t_pbuf_spec)));
-	if (! d) {
-	    reply_Uint_posix_error(desc, 0, ENOMEM);
-	    goto done;
-	}
-	d->command = command;
-	d->reply = !0;
-	d->fd = desc->fd;
-	d->flags = desc->flags;
-#ifdef USE_VM_PROBES
-	dt_i1 = d->fd;
-	dt_i2 = d->flags;
-#endif
-	d->c.pwritev.port = desc->port;
-	d->c.pwritev.q_mtx = desc->q_mtx;
-	d->c.pwritev.n = n;
-	d->c.pwritev.cnt = 0;
-	total = 0;
-	j = 0;
-	/* Create pos/size specs in the thread data structure
-	 * for all non-zero size binaries. Calculate total size.
-	 */
-	for(i = 0; i < n; i++) {
-	    Uint32 sizeH, sizeL;
-	    size_t size;
-	    if (   !EV_GET_SINT64(ev, &d->c.pwritev.specs[i].offset, &p, &q)
-		|| !EV_GET_UINT32(ev, &sizeH, &p, &q)
-		|| !EV_GET_UINT32(ev, &sizeL, &p, &q)) {
-		/* Misalignment in buffer */
-		reply_Uint_posix_error(desc, 0, EINVAL);
-		EF_FREE(d);
-		goto done;
-	    }
-#if SIZEOF_SIZE_T == 4
-	    if (sizeH != 0) {
-		reply_Uint_posix_error(desc, 0, EINVAL);
-		EF_FREE(d);
-		goto done;
-	    }
-	    size = sizeL;
-#else
-	    size = ((size_t)sizeH<<32) | sizeL;
-#endif
-	    if (size > 0) {
-		total += size;
-		d->c.pwritev.specs[j].size = size;
-		j++;
-	    }
-	}
-	d->c.pwritev.size = total;
-#ifdef USE_VM_PROBES
-	dt_i3 = d->c.pwritev.size;
-#endif
-	if (j == 0) {
-	    /* Trivial case - nothing to write */
-	    EF_FREE(d);
-	    reply_Uint(desc, 0);
-	} else {
-	    ErlDrvSizeT skip = 1 + 4 + 8 * (2*n) 
-#ifdef USE_VM_PROBES
-		+ dt_utag_bytes
-#endif
-		;
-	    if (skip + total != ev->size) {
-		/* Actual amount of data does not match 
-		 * total of all pos/size specs
-		 */
-		EF_FREE(d);
-		reply_Uint_posix_error(desc, 0, EINVAL);
-	    } else {
-		/* Enqueue the data */
-		MUTEX_LOCK(desc->q_mtx);
-		driver_enqv(desc->port, ev, skip);
-		MUTEX_UNLOCK(desc->q_mtx);
-		/* Execute the command */
-		d->invoke = invoke_pwritev;
-		d->free = free_data;
-		d->level = 1;
-		cq_enq(desc, d);
-	    }
-	}
-    } goto done; /* case FILE_PWRITEV: */
-
-    case FILE_PREADV: { /* Dtrace: The dtrace user tag is not last in message, 
-			   but follows the message tag directly. 
-			   This is handled specially in prim_file.erl */
-	register void * void_ptr;
-	Uint32 i, n;
-	ErlIOVec *res_ev;
-#ifdef USE_VM_PROBES
-	char dt_tmp;
-	int dt_utag_bytes = 1;
-	/* This will work for UTF-8, but not for UTF-16 - extra reminder here */
-#ifdef FILENAMES_16BIT 
-#error 16bit characters in filenames and dtrace in combination is not supported.
-#endif
-	dt_utag = EV_CHAR_P(ev, p, q);
-	while (EV_GET_CHAR(ev, &dt_tmp, &p, &q) && dt_tmp != '\0') {
-	    dt_utag_bytes++;
-	}
-#endif
-	if (lseek_flush_read(desc, &err
-#ifdef USE_VM_PROBES
-			     , dt_priv, dt_utag
-#endif
-			     ) < 0) {
-	    reply_posix_error(desc, err);
-	    goto done;
-	}
-	if (flush_write_check_error(desc, &err
-#ifdef USE_VM_PROBES
-				    , dt_priv, dt_utag
-#endif
-				    ) < 0) {
-	    reply_posix_error(desc, err);
-	    goto done;
-	}
-	if (ev->size < 1+8
-#ifdef USE_VM_PROBES
-	    + dt_utag_bytes
-#endif
-	    || !EV_GET_UINT32(ev, &n, &p, &q)
-	    || !EV_GET_UINT32(ev, &n, &p, &q)) {
-	    /* Buffer too short to contain even the number of pos/size specs */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-	if (ev->size < 1+8+8*(2*n)
-#ifdef USE_VM_PROBES
-	    + dt_utag_bytes
-#endif
-	    ) {
-	    /* Buffer wrong length to contain the pos/size specs */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-	/* Create the thread data structure with the contained ErlIOVec 
-	 * and corresponding binaries for the response 
-	 */
-	d = EF_ALLOC(sizeof(*d)
-		     + (n * sizeof(*d->c.preadv.offsets))
-		     + ((1+n) * (sizeof(*res_ev->iov)
-				 + sizeof(*res_ev->binv))));
-	if (! d) {
-	    reply_posix_error(desc, ENOMEM);
-	    goto done;
-	}
-	d->command = command;
-	d->reply = !0;
-	d->fd = desc->fd;
-	d->flags = desc->flags;
-#ifdef USE_VM_PROBES
-	dt_i1 = d->fd;
-	dt_i2 = d->flags;
-#endif
-	d->c.preadv.n = n;
-	d->c.preadv.cnt = 0;
-	d->c.preadv.size = 0;
-	res_ev = &d->c.preadv.eiov;
-	/* XXX possible alignment problems here for weird machines */
-	res_ev->vsize = 1+d->c.preadv.n;
-	res_ev->iov = void_ptr = &d->c.preadv.offsets[d->c.preadv.n];
-	res_ev->binv = void_ptr = &res_ev->iov[res_ev->vsize];
-	/* Read in the pos/size specs and allocate binaries for the results */
-	for (i = 1; i < 1+n; i++) {
-	    Uint32 sizeH, sizeL;
-	    size_t size;
-	    if (   !EV_GET_SINT64(ev, &d->c.preadv.offsets[i-1], &p, &q)
-		|| !EV_GET_UINT32(ev, &sizeH, &p, &q)
-		|| !EV_GET_UINT32(ev, &sizeL, &p, &q)) {
-		reply_posix_error(desc, EINVAL);
-		break;
-	    }
-#if SIZEOF_SIZE_T == 4
-	    if (sizeH != 0) {
-		reply_posix_error(desc, EINVAL);
-		break;
-	    }
-	    size = sizeL;
-#else
-	    size = ((size_t)sizeH<<32) | sizeL;
-#endif
-#ifdef USE_VM_PROBES
-	    dt_i3 += size;
-#endif
-	    if (! (res_ev->binv[i] = driver_alloc_binary(size))) {
-		reply_posix_error(desc, ENOMEM);
-		break;
-	    } else {
-		res_ev->iov[i].iov_len  = size;
-		res_ev->iov[i].iov_base = res_ev->binv[i]->orig_bytes;
-	    }
-	}
-	if (i < 1+n) {
-	    for (i--; i > 0; i--) {
-		driver_free_binary(res_ev->binv[i]);
-	    }
-	    EF_FREE(d);
-	    goto done;
-	}
-	/* Allocate the header binary (index 0) */
-	res_ev->binv[0] = driver_alloc_binary(4+4+8*n);
-	if (! res_ev->binv[0]) {
-	    reply_posix_error(desc, ENOMEM);
-	    for (i = 1; i < 1+n; i++) {
-		driver_free_binary(res_ev->binv[i]);
-	    }
-	    EF_FREE(d);
-	    goto done;
-	}
-	res_ev->iov[0].iov_len = 4+4+8*n;
-	res_ev->iov[0].iov_base = res_ev->binv[0]->orig_bytes;
-	/* Fill in the number of buffers in the header */
-	put_int32(0, res_ev->iov[0].iov_base);
-	put_int32(n, (char *)(res_ev->iov[0].iov_base) + 4);
-	/**/
-	res_ev->size = res_ev->iov[0].iov_len;
-	if (n == 0) {
-	    /* Trivial case - nothing to read */
-	    reply_ev(desc, FILE_RESP_LDATA, res_ev);
-	    free_preadv(d);
-	    goto done;
-	} else {
-	    d->invoke = invoke_preadv;
-	    d->free = free_preadv;
-	    d->level = 1;
-	    cq_enq(desc, d);
-	}
-    } goto done; /* case FILE_PREADV: */
-
-    case FILE_LSEEK: {
-	Sint64 offset;		/* Offset for seek */
-	Uint32 origin;		/* Origin of seek. */
-
-	if (ev->size < 1+8+4
-	    || !EV_GET_SINT64(ev, &offset, &p, &q)
-	    || !EV_GET_UINT32(ev, &origin, &p, &q)) {
-	    /* Wrong length of buffer to contain offset and origin */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-#ifdef USE_VM_PROBES
-	dt_utag = EV_CHAR_P(ev, p, q);
-#endif
-	if (lseek_flush_read(desc, &err
-#ifdef USE_VM_PROBES
-			     , dt_priv, dt_utag
-#endif
-			     ) < 0) {
-	    reply_posix_error(desc, err);
-	    goto done;
-	}
-	if (flush_write_check_error(desc, &err
-#ifdef USE_VM_PROBES
-				    , dt_priv, dt_utag
-#endif
-				    ) < 0) {
-	    reply_posix_error(desc, err);
-	    goto done;
-	}
-	if ((d = async_lseek(desc, &err, !0, offset, origin
-#ifdef USE_VM_PROBES
-			     , &dt_i1, &dt_i2, &dt_i3
-#endif
-			     )) == NULL) {
-	    reply_posix_error(desc, err);
-	    goto done;
-	}
-    } goto done;
-
-    case FILE_READ_FILE: {
-	char *filename;
-	if (ev->size < 1+1) {
-	    /* Buffer contains empty name */
-	    reply_posix_error(desc, ENOENT);
-	    goto done;
-	}
-#ifndef USE_VM_PROBES
-	/* In the dtrace case, the iov has an extra element, the dtrace utag - we will need 
-	   another test to see that
-	   the filename is in a single buffer: */
-	if (ev->size-1 != ev->iov[q].iov_len-p) {
-	    /* Name not in one single buffer */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-#else
-	if (((byte *)ev->iov[q].iov_base)[ev->iov[q].iov_len-1] != '\0') {
-	    /* Name not in one single buffer */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}	
-#endif
-	filename = EV_CHAR_P(ev, p, q);
-	d = EF_ALLOC(sizeof(struct t_data) -1 + FILENAME_BYTELEN(filename) + FILENAME_CHARSIZE);
-	if (! d) {
-	    reply_posix_error(desc, ENOMEM);
-	    goto done;
-	}
-	d->command = command;
-	d->reply = !0;
-	/* Copy name */
-	FILENAME_COPY(d->b, filename);
-#ifdef USE_VM_PROBES
-	{
-	    char dt_tmp;
-
-	    /* This will work for UTF-8, but not for UTF-16 - extra reminder here */
-#ifdef FILENAMES_16BIT 
-#error 16bit characters in filenames and dtrace in combination is not supported.
-#endif
-	    while (EV_GET_CHAR(ev, &dt_tmp, &p, &q) && dt_tmp != '\0') 
-		;
-	    dt_s1 = d->b;
-	    dt_utag = EV_CHAR_P(ev, p, q);
-	}
-#endif
-	d->c.read_file.binp = NULL;
-	d->invoke = invoke_read_file;
-	d->free = free_read_file;
-	d->level = 2;
-	cq_enq(desc, d);
-    } goto done;
-
-    case FILE_IPREAD: {
-	/* This operation cheets by using invoke_preadv() and free_preadv()
-	 * plus its own invoke_ipread. Therefore the result format is 
-	 * a bit awkward - the header binary contains one extra 64 bit
-	 * field that invoke_preadv() fortunately ignores,
-	 * and the first 64 bit field does not contain the number of 
-	 * data binaries which invoke_preadv() also ignores.
-	 */
-	register void * void_ptr;
-	char mode;
-	Sint64 hdr_offset;
-	Uint32 max_size;
-	ErlIOVec *res_ev;
-	int vsize;
-	if (! EV_GET_CHAR(ev, &mode, &p, &q)) {
-	    /* Empty command */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-	if (mode != IPREAD_S32BU_P32BU) {
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-	if (ev->size < 1+1+8+4
-	    || !EV_GET_SINT64(ev, &hdr_offset, &p, &q)
-	    || !EV_GET_UINT32(ev, &max_size, &p, &q)) {
-	    /* Buffer too short to contain 
-	     * the header offset and max size spec */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-#ifdef USE_VM_PROBES
-	dt_utag = EV_CHAR_P(ev, p, q);
-#endif
-	if (lseek_flush_read(desc, &err
-#ifdef USE_VM_PROBES
-			     , dt_priv, dt_utag
-#endif
-			     ) < 0) {
-	    reply_posix_error(desc, err);
-	    goto done;
-	}
-	if (flush_write_check_error(desc, &err
-#ifdef USE_VM_PROBES
-				    , dt_priv, dt_utag
-#endif
-				    ) < 0) {
-	    reply_posix_error(desc, err);
-	    goto done;
-	}
-	/* Create the thread data structure with the contained ErlIOVec 
-	 * and corresponding binaries for the response 
-	 */
-	vsize = 2;
-	d = EF_ALLOC(sizeof(*d) + 
-		     vsize*(sizeof(*res_ev->iov) + sizeof(*res_ev->binv)));
-	if (! d) {
-	    reply_posix_error(desc, ENOMEM);
-	    goto done;
-	}
-	d->command = command;
-	d->reply = !0;
-	d->fd = desc->fd;
-	d->flags = desc->flags;
-	d->c.preadv.offsets[0] = hdr_offset;
-	d->c.preadv.size = max_size;
-#ifdef USE_VM_PROBES
-	dt_i1 = d->fd;
-	dt_i2 = d->flags;
-	dt_i3 = d->c.preadv.offsets[0];
-	dt_i4 = d->c.preadv.size;
-#endif
-	res_ev = &d->c.preadv.eiov;
-	/* XXX possible alignment problems here for weird machines */
-	res_ev->iov = void_ptr = d + 1;
-	res_ev->binv = void_ptr = res_ev->iov + vsize;
-	res_ev->size = 0;
-	res_ev->vsize = 0;
-	d->invoke = invoke_ipread;
-	d->free = free_preadv;
-	d->level = 1;
-	cq_enq(desc, d);
-    } goto done; /* case FILE_IPREAD: */
-
-    case FILE_SETOPT: {
-	char opt;
-
-	if (ev->size < 1+1
-	    || !EV_GET_CHAR(ev, &opt, &p, &q)) {
-	    /* Buffer too short to contain even the option type */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-#ifdef USE_VM_PROBES
-	dt_i1 = opt;
-	dt_utag = EV_CHAR_P(ev, p, q);
-#endif
-	switch (opt) {
-	case FILE_OPT_DELAYED_WRITE: {
-	    Uint32 sizeH, sizeL, delayH, delayL;
-	    if (ev->size != 1+1+4*sizeof(Uint32)
-#ifdef USE_VM_PROBES
-		+ FILENAME_BYTELEN(dt_utag) + FILENAME_CHARSIZE
-#endif
-		|| !EV_GET_UINT32(ev, &sizeH, &p, &q)
-		|| !EV_GET_UINT32(ev, &sizeL, &p, &q)
-		|| !EV_GET_UINT32(ev, &delayH, &p, &q)
-		|| !EV_GET_UINT32(ev, &delayL, &p, &q)) {
-		/* Buffer has wrong length to contain the option values */
-		reply_posix_error(desc, EINVAL);
-		goto done;
-	    }
-#if SIZEOF_SIZE_T == 4
-	    if (sizeH != 0) {
-		reply_posix_error(desc, EINVAL);
-		goto done;
-	    }
-	    desc->write_bufsize = sizeL;
-#else
-	    desc->write_bufsize = ((size_t)sizeH << 32) | sizeL;
-#endif
-#if SIZEOF_LONG == 4
-	    if (delayH != 0) {
-		reply_posix_error(desc, EINVAL);
-		goto done;
-	    }
-	    desc->write_delay = delayL;
-#else
-	    desc->write_delay = ((unsigned long)delayH << 32) | delayL;
-#endif
-#ifdef USE_VM_PROBES
-	    dt_i2 = desc->write_delay;
-#endif
-	    TRACE_C('K');
-	    reply_ok(desc);
-	} goto done;
-	case FILE_OPT_READ_AHEAD: {
-	    Uint32 sizeH, sizeL;
-	    if (ev->size != 1+1+2*sizeof(Uint32)
-#ifdef USE_VM_PROBES
-		+ FILENAME_BYTELEN(dt_utag)+FILENAME_CHARSIZE
-#endif
-		|| !EV_GET_UINT32(ev, &sizeH, &p, &q)
-		|| !EV_GET_UINT32(ev, &sizeL, &p, &q)) {
-		/* Buffer has wrong length to contain the option values */
-		reply_posix_error(desc, EINVAL);
-		goto done;
-	    }
-#if SIZEOF_SIZE_T == 4
-	    if (sizeH != 0) {
-		reply_posix_error(desc, EINVAL);
-		goto done;
-	    }
-	    desc->read_bufsize = sizeL;
-#else
-	    desc->read_bufsize = ((size_t)sizeH << 32) | sizeL;
-#endif
-#ifdef USE_VM_PROBES
-	    dt_i2 = desc->read_bufsize;
-#endif
-	    TRACE_C('K');
-	    reply_ok(desc);
-	} goto done;
-	default:
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	} /* case FILE_OPT_DELAYED_WRITE: */
-    } ASSERT(0); goto done; /* case FILE_SETOPT: */
-
-    case FILE_SENDFILE: {
-
-#ifdef HAVE_SENDFILE
-        struct t_data *d;
-	Uint32 out_fd, offsetH, offsetL, hd_len, tl_len;
-	Uint64 nbytes;
-	char flags;
-
-	if (ev->size < 1 + 7 * sizeof(Uint32) + sizeof(char)
-		|| !EV_GET_UINT32(ev, &out_fd, &p, &q)
-		|| !EV_GET_CHAR(ev, &flags, &p, &q)
-		|| !EV_GET_UINT32(ev, &offsetH, &p, &q)
-		|| !EV_GET_UINT32(ev, &offsetL, &p, &q)
-		|| !EV_GET_UINT64(ev, &nbytes, &p, &q)
-		|| !EV_GET_UINT32(ev, &hd_len, &p, &q)
-		|| !EV_GET_UINT32(ev, &tl_len, &p, &q)) {
-	    /* Buffer has wrong length to contain all the needed values */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-
-	if (hd_len != 0 || tl_len != 0) {
-	    /* We do not allow header, trailers */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-
-	
-	if (flags & SENDFILE_FLGS_USE_THREADS && !THRDS_AVAILABLE) {
-	    /* We do not allow use_threads flag on a system where
-	       no threads are available. */
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-
-	d = EF_SAFE_ALLOC(sizeof(struct t_data));
-	d->fd = desc->fd;
-	d->command = command;
-	d->invoke = invoke_sendfile;
-	d->free = free_sendfile;
-	d->flags = flags;
-	d->level = 2;
-
-	d->c.sendfile.out_fd = (int) out_fd;
-	d->c.sendfile.written = 0;
-	d->c.sendfile.port = desc->port;
-	d->c.sendfile.q_mtx = desc->q_mtx;
-
-    #if SIZEOF_OFF_T == 4
-	if (offsetH != 0) {
-	    reply_posix_error(desc, EINVAL);
-	    goto done;
-	}
-	d->c.sendfile.offset = (off_t) offsetL;
-    #else
-	d->c.sendfile.offset = ((off_t) offsetH << 32) | offsetL;
-    #endif
-
-	d->c.sendfile.nbytes = nbytes;
-
-	if (USE_THRDS_FOR_SENDFILE(d)) {
-	    SET_BLOCKING(d->c.sendfile.out_fd);
-	} else {
-	    /**
-	     * Write a place holder to queue in order to force file_flush
-	     * to be called before the driver is closed.
-	     */
-	    char tmp[1] = "";
-	    MUTEX_LOCK(d->c.sendfile.q_mtx);
-	    if (driver_enq(d->c.sendfile.port, tmp, 1)) {
-	        MUTEX_UNLOCK(d->c.sendfile.q_mtx);
-		reply_posix_error(desc, ENOMEM);
-		goto done;
-	    }
-	    MUTEX_UNLOCK(d->c.sendfile.q_mtx);
-	}
-
-	cq_enq(desc, d);
-#else
-	reply_posix_error(desc, ENOTSUP);
-#endif
-	goto done;
-        } /* case FILE_SENDFILE: */
-
-    } /* switch(command) */
-
-    if (lseek_flush_read(desc, &err
-#ifdef USE_VM_PROBES
-			 , dt_priv, dt_utag
-#endif
-			 ) < 0) {
-	reply_posix_error(desc, err);
-	goto done;
-    }
-    if (flush_write_check_error(desc, &err
-#ifdef USE_VM_PROBES
-				, dt_priv, dt_utag
-#endif
-				) < 0) {
-	reply_posix_error(desc, err);
-	goto done;
-    } else {
-	/* Flatten buffer and send it to file_output(desc, buf, len) */
-	int len = ev->size;
-	char *buf = EF_ALLOC(len);
-	if (! buf) {
-	    reply_posix_error(desc, ENOMEM);
-	    goto done;
-	}
-	driver_vec_to_buf(ev, buf, len);
-	file_output((ErlDrvData) desc, buf, len);
-	EF_FREE(buf);
-	goto done;
-    }
-
- done:
-    if (d != NULL) {
-#ifdef USE_VM_PROBES
-	/*
-	 * If d == NULL, then either:
-	 *    1). There was an error of some sort, or
-	 *    2). The command given to us is actually implemented
-	 *	  by file_output() instead.
-	 *
-	 * Case #1 is probably a TODO item, perhaps?
-	 * Case #2 we definitely don't want to activate a probe.
-	 */
-	d->sched_i1 = dt_priv->thread_num;
-	d->sched_i2 = dt_priv->tag;
-	d->sched_utag[0] = '\0';
-	if (dt_utag != NULL) {
-	    if (dt_utag[0] == '\0') {
-                dt_utag = NULL;
-            } else {
-		strncpy(d->sched_utag, dt_utag, sizeof(d->sched_utag) - 1);
-		d->sched_utag[sizeof(d->sched_utag) - 1] = '\0';
-	    }
-	}
-	DTRACE11(efile_drv_entry, dt_priv->thread_num, dt_priv->tag++,
-		 dt_utag, command, dt_s1, NULL, dt_i1, dt_i2, dt_i3, dt_i4,
-		 desc->port_str);
-#endif
-    }
-    cq_execute(desc);
-}
-
-#ifdef  USE_VM_PROBES
-dt_private *
-get_dt_private(int base)
-{
-    dt_private *dt_priv = (dt_private *) pthread_getspecific(dt_driver_key);
-
-    if (dt_priv == NULL) {
-	dt_priv = EF_SAFE_ALLOC(sizeof(dt_private));
-	erts_mtx_lock(&dt_driver_mutex);
-	dt_priv->thread_num = (base + dt_driver_idnum++);
-	erts_mtx_unlock(&dt_driver_mutex);
-	dt_priv->tag = 0;
-	pthread_setspecific(dt_driver_key, dt_priv);
-    }
-    return dt_priv;
-}
-#endif  /* USE_VM_PROBES */
diff --git a/erts/emulator/drivers/common/erl_efile.h b/erts/emulator/drivers/common/erl_efile.h
deleted file mode 100644
index b7f063b4f2..0000000000
--- a/erts/emulator/drivers/common/erl_efile.h
+++ /dev/null
@@ -1,176 +0,0 @@
-/*
- * %CopyrightBegin%
- *
- * Copyright Ericsson AB 1997-2016. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * %CopyrightEnd%
- */
-/*
- * Defines the interfaces between the generic efile driver and its
- * operating-system dependent helpers.
- */
-
-#include "sys.h"
-#include "erl_driver.h"
-
-/*
- * Open modes for efile_openfile().
- */
-#define EFILE_MODE_READ 1
-#define EFILE_MODE_WRITE 2	/* Implies truncating file when used alone. */
-#define EFILE_MODE_READ_WRITE 	3
-#define EFILE_MODE_APPEND	4
-#define EFILE_COMPRESSED 	8
-#define EFILE_MODE_EXCL        16
-#define EFILE_NO_TRUNCATE      32 /* Special for reopening on VxWorks */
-#define EFILE_MODE_SYNC        64
-
-/*
- * Seek modes for efile_seek().
- */
-#define	EFILE_SEEK_SET	0
-#define	EFILE_SEEK_CUR	1
-#define	EFILE_SEEK_END	2
-
-/*
- * File types returned by efile_fileinfo().
- */
-#define FT_DEVICE 	1
-#define FT_DIRECTORY 	2
-#define FT_REGULAR	3
-#define FT_SYMLINK	4
-#define FT_OTHER	5
-
-/*
- * Access attributes returned by efile_fileinfo() (the bits can be ORed
- * together).
- */
-#define FA_NONE    	0
-#define FA_WRITE 	1
-#define FA_READ		2
-
-/* Some OS'es (i.e. Windows) has filenames in wide charaqcters. That requires special handling */
-/* Note that we do *not* honor alignment in the communication to the OS specific driver, */
-/* which is not a problem on x86, but might be on other platforms. The OS specific efile */
-/* implementation is expected to align if needed */
-#ifdef __WIN32__
-#define FILENAMES_16BIT 1
-#endif
-
-/* We use sendfilev if it exist on solaris */
-#if !defined(HAVE_SENDFILE) && defined(HAVE_SENDFILEV)
-#define HAVE_SENDFILE
-#endif
-
-/*
- * An handle to an open directory.  To be cast to the correct type
- * in the system-dependent directory functions.
- */
-
-typedef struct _Efile_Dir_Handle* EFILE_DIR_HANDLE;
-
-/*
- * Error information from the last call.
- */  
-typedef struct _Efile_error {
-    int posix_errno;		/* Posix error number, as in <errno.h>. */
-    int os_errno;		/* Os-dependent error number (not used). */
-} Efile_error;
-
-/*
- * Describes what is returned by file:file_info/1.
- */
-
-typedef struct _Efile_info {
-    Uint32 size_low;		/* Size of file, lower 32 bits.. */
-    Uint32 size_high;		/* Size of file, higher 32 bits. */
-    Uint32 type;		/* Type of file -- one of FT_*. */
-    Uint32 access;		/* Access to file -- one of FA_*. */
-    Uint32 mode;		/* Access permissions -- bit field. */
-    Uint32 links;		/* Number of links to file. */
-    Uint32 major_device;	/* Major device or file system. */
-    Uint32 minor_device;	/* Minor device (for devices). */
-    Uint32 inode;		/* Inode number. */
-    Uint32 uid;			/* User id of owner. */
-    Uint32 gid;			/* Group id of owner. */
-    Sint64 accessTime;		/* Last time the file was accessed. */
-    Sint64 modifyTime;		/* Last time the file was modified. */
-    Sint64 cTime;		/* Creation time (Windows) or last
-				 * inode change (Unix).
-				 */
-} Efile_info;
-
-
-#ifdef HAVE_SENDFILE
-/*
- * Describes the structure of headers/trailers for sendfile
- */
-struct t_sendfile_hdtl {
-    SysIOVec *headers;
-    int hdr_cnt;
-    SysIOVec *trailers;
-    int trl_cnt;
-};
-#endif /* HAVE_SENDFILE */
-
-/*
- * Functions.
- */
-int efile_init(void);
-int efile_mkdir(Efile_error* errInfo, char* name);
-int efile_rmdir(Efile_error* errInfo, char* name);
-int efile_delete_file(Efile_error* errInfo, char* name);
-int efile_rename(Efile_error* errInfo, char* src, char* dst);
-int efile_chdir(Efile_error* errInfo, char* name);
-int efile_getdcwd(Efile_error* errInfo, int drive,
-		  char* buffer, size_t size);
-int efile_readdir(Efile_error* errInfo, char* name, 
-		  EFILE_DIR_HANDLE* dir_handle,
-		  char* buffer, size_t *size);
-int efile_openfile(Efile_error* errInfo, char* name, int flags,
-		   int* pfd, Sint64* pSize);
-void efile_closefile(int fd);
-int efile_fdatasync(Efile_error* errInfo, int fd);
-int efile_fsync(Efile_error* errInfo, int fd);
-int efile_fileinfo(Efile_error* errInfo, Efile_info* pInfo,
-		   char *name, int info_for_link);
-int efile_write_info(Efile_error* errInfo, Efile_info* pInfo, char *name);
-int efile_write(Efile_error* errInfo, int flags, int fd, 
-		char* buf, size_t count);
-int efile_writev(Efile_error* errInfo, int flags, int fd, 
-		 SysIOVec* iov, int iovcnt);
-int efile_read(Efile_error* errInfo, int flags, int fd, 
-	       char* buf, size_t count, size_t* pBytesRead);
-int efile_seek(Efile_error* errInfo, int fd, 
-	       Sint64 offset, int origin, Sint64* new_location);
-int efile_truncate_file(Efile_error* errInfo, int *fd, int flags);
-int efile_pwrite(Efile_error* errInfo, int fd, 
-		 char* buf, size_t count, Sint64 offset);
-int efile_pread(Efile_error* errInfo, int fd, 
-		Sint64 offset, char* buf, size_t count, size_t* pBytesRead);
-int efile_readlink(Efile_error* errInfo, char *name, 
-		   char* buffer, size_t size);
-int efile_altname(Efile_error* errInfo, char *name, 
-		  char* buffer, size_t size);
-int efile_link(Efile_error* errInfo, char* old, char* new);
-int efile_symlink(Efile_error* errInfo, char* old, char* new);
-int efile_may_openfile(Efile_error* errInfo, char *name);
-int efile_fadvise(Efile_error* errInfo, int fd, Sint64 offset, Sint64 length,
-		  int advise);
-#ifdef HAVE_SENDFILE
-int efile_sendfile(Efile_error* errInfo, int in_fd, int out_fd,
-		      off_t *offset, Uint64 *nbytes, struct t_sendfile_hdtl *hdtl);
-#endif /* HAVE_SENDFILE */
-int efile_fallocate(Efile_error* errInfo, int fd, Sint64 offset, Sint64 length);
diff --git a/erts/emulator/drivers/common/gzio.c b/erts/emulator/drivers/common/gzio.c
index f60c781894..86c3b07cea 100644
--- a/erts/emulator/drivers/common/gzio.c
+++ b/erts/emulator/drivers/common/gzio.c
@@ -19,726 +19,16 @@
 #include <unistd.h>
 #endif
 #include <ctype.h>
+
 #include "erl_driver.h"
-#include "erl_efile.h"
 #include "sys.h"
 
-#ifdef __WIN32__
-#ifndef HAVE_CONFLICTING_FREAD_DECLARATION
-#define HAVE_CONFLICTING_FREAD_DECLARATION
-#endif
-#define FILENAMES_16BIT 1
-#endif
-
-#ifdef STDC
-#  define zstrerror(errnum) strerror(errnum)
-#else
-#  define zstrerror(errnum) ""
-#endif
-
 #include "gzio_zutil.h"
 #include "erl_zlib.h"
 #include "gzio.h"
 
-/********struct internal_state {int dummy;}; / * for buggy compilers */
-
-#define Z_BUFSIZE 4096
-
-#define ALLOC(size) driver_alloc(size)
-#define TRYFREE(p) {if (p) driver_free(p);}
-
 static int gz_magic[2] = {0x1f, 0x8b}; /* gzip magic header */
 
-/* gzip flag byte */
-#define ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
-#define HEAD_CRC     0x02 /* bit 1 set: header CRC present */
-#define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
-#define ORIG_NAME    0x08 /* bit 3 set: original file name present */
-#define COMMENT      0x10 /* bit 4 set: file comment present */
-#define RESERVED     0xE0 /* bits 5..7: reserved */
-
-typedef struct gz_stream {
-    z_stream stream;
-    int      z_err;   /* error code for last stream operation */
-    int      z_eof;   /* set if end of input file */
-#ifdef UNIX
-    int      file;    /* .gz file descriptor */
-#else
-    FILE     *file;   /* .gz file */
-#endif
-    Byte     *inbuf;  /* input buffer */
-    Byte     *outbuf; /* output buffer */
-    uLong    crc;     /* crc32 of uncompressed data */
-    char     *msg;    /* error message */
-    char     *path;   /* path name for debugging only */
-    int      transparent; /* 1 if input file is not a .gz file */
-    char     mode;    /* 'w' or 'r' */
-    int      position; /* Position (for seek) */
-    int (*destroy)(struct gz_stream*); /* Function to destroy
-					    *  this structure. */
-} gz_stream;
-
-local ErtsGzFile gz_open      (const char *path, const char *mode);
-local int    get_byte     (gz_stream *s);
-local void   check_header (gz_stream *s);
-local int    destroy      (gz_stream *s);
-local uLong  getLong      (gz_stream *s);
-
-#ifdef UNIX
-/*
- * In Solaris 8 and earlier, fopen() and its friends cannot handle 
- * file descriptors larger than 255. Therefore, we use read()/write()
- * on all Unix systems.
- */
-# define ERTS_GZWRITE(File, Buf, Count) write((File), (Buf), (Count))
-# define ERTS_GZREAD(File, Buf, Count) read((File), (Buf), (Count))
-#else
-/*
- * On all other operating systems, using fopen(), fread()/fwrite(), since
- * there is not guaranteed to exist any read()/write() (not part of
- * ANSI/ISO-C).
- */
-# define ERTS_GZWRITE(File, Buf, Count) fwrite((Buf), 1, (Count), (File))
-# define ERTS_GZREAD(File, Buf, Count) fread((Buf), 1, (Count), (File))
-#endif
-
-/*
- * Ripped from efile_drv.c
- */
-
-#ifdef FILENAMES_16BIT
-#  define FILENAME_BYTELEN(Str) filename_len_16bit(Str)
-#  define FILENAME_COPY(To,From) filename_cpy_16bit((To),(From)) 
-#  define FILENAME_CHARSIZE 2
-
-   static int filename_len_16bit(const char *str) 
-   {
-       const char *p = str;
-       while(*p != '\0' || p[1] != '\0') {
-	   p += 2;
-       }
-       return (p - str);
-   }
-
-   static void filename_cpy_16bit(char *to, const char *from) 
-   {
-       while(*from != '\0' || from[1] != '\0') {
-	   *to++ = *from++;
-	   *to++ = *from++;
-       }
-       *to++ = *from++;
-       *to++ = *from++;
-   }
-
-#else
-#  define FILENAME_BYTELEN(Str) strlen(Str)
-#  define FILENAME_COPY(To,From) strcpy(To,From) 
-#  define FILENAME_CHARSIZE 1
-#endif
-
-/* ===========================================================================
-     Opens a gzip (.gz) file for reading or writing. The mode parameter
-   is as in fopen ("rb" or "wb"). The file is given either by file descriptor
-   or path name (if fd == -1).
-     gz_open return NULL if the file could not be opened or if there was
-   insufficient memory to allocate the (de)compression state; errno
-   can be checked to distinguish the two cases (if errno is zero, the
-   zlib error is Z_MEM_ERROR).
-*/
-local ErtsGzFile gz_open (path, mode)
-    const char *path;
-    const char *mode;
-{
-    int err;
-    int level = Z_DEFAULT_COMPRESSION; /* compression level */
-    char *p = (char*)mode;
-    gz_stream *s;
-    char fmode[80]; /* copy of mode, without the compression level */
-    char *m = fmode;
-
-    if (!path || !mode) return Z_NULL;
-
-    s = (gz_stream *)ALLOC(sizeof(gz_stream));
-    if (!s) return Z_NULL;
-
-    erl_zlib_alloc_init(&s->stream);
-    s->stream.next_in = s->inbuf = Z_NULL;
-    s->stream.next_out = s->outbuf = Z_NULL;
-    s->stream.avail_in = s->stream.avail_out = 0;
-#ifdef UNIX
-    s->file = -1;
-#else
-    s->file = NULL;
-#endif
-    s->z_err = Z_OK;
-    s->z_eof = 0;
-    s->crc = crc32(0L, Z_NULL, 0);
-    s->msg = NULL;
-    s->transparent = 0;
-    s->position = 0;
-    s->destroy = destroy;
-
-    s->path = (char*)ALLOC(FILENAME_BYTELEN(path)+FILENAME_CHARSIZE);
-    if (s->path == NULL) {
-        return s->destroy(s), (ErtsGzFile)Z_NULL;
-    }
-    FILENAME_COPY(s->path, path); /* do this early for debugging */
-
-    s->mode = '\0';
-    do {
-        if (*p == 'r')
-	    s->mode = 'r';
-	if (*p == 'w' || *p == 'a')
-	    s->mode = 'w';
-	if (isdigit((int)*p)) {
-	    level = *p - '0';
-	} else {
-	    *m++ = *p;		/* Copy the mode */
-	}
-    } while (*p++ && m < fmode + sizeof(fmode) - 1);
-    *m = '\0';
-    if (s->mode == '\0')
-	return s->destroy(s), (ErtsGzFile)Z_NULL;
-    
-    if (s->mode == 'w') {
-        err = deflateInit2(&(s->stream), level,
-                           Z_DEFLATED, MAX_WBITS+16, DEF_MEM_LEVEL, 0);
-        /* windowBits is passed < 0 to suppress zlib header */
-
-        s->stream.next_out = s->outbuf = (Byte*)ALLOC(Z_BUFSIZE);
-
-        if (err != Z_OK || s->outbuf == Z_NULL) {
-            return s->destroy(s), (ErtsGzFile)Z_NULL;
-        }
-    } else {
-	/*
-	 * It is tempting to use the built-in support in zlib
-	 * for handling GZIP headers, but unfortunately it
-	 * cannot handle multiple GZIP headers (which occur when
-	 * several GZIP files have been concatenated).
-	 */
-
-	err = inflateInit2(&(s->stream), -MAX_WBITS);
-        s->stream.next_in  = s->inbuf = (Byte*)ALLOC(Z_BUFSIZE);
-
-        if (err != Z_OK || s->inbuf == Z_NULL) {
-            return s->destroy(s), (ErtsGzFile)Z_NULL;
-        }
-    }
-    s->stream.avail_out = Z_BUFSIZE;
-
-    errno = 0;
-#if defined(FILENAMES_16BIT)
-    {
-	FILE* efile_wfopen(const WCHAR* name, const WCHAR* mode);
-	WCHAR wfmode[80];
-	int i = 0;
-	int j;
-	for(j = 0; fmode[j] != '\0'; ++j) {
-	    wfmode[i++] = (WCHAR) fmode[j];
-	}
-	wfmode[i++] = L'\0';
-	s->file = efile_wfopen((WCHAR *)path, wfmode);
-	if (s->file == NULL) {
-	    return s->destroy(s), (ErtsGzFile)Z_NULL;
-	}
-    }
-#elif defined(UNIX)
-    if (s->mode == 'r') {
-	s->file = open(path, O_RDONLY);
-    } else {
-	s->file = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0666);
-    }
-    if (s->file == -1) {
-        return s->destroy(s), (ErtsGzFile)Z_NULL;
-    }
-#else
-    s->file = fopen(path, fmode);
-    if (s->file == NULL) {
-        return s->destroy(s), (ErtsGzFile)Z_NULL;
-    }
-#endif
-    if (s->mode == 'r') {
-	check_header(s); /* skip the .gz header */
-    }
-    return (ErtsGzFile)s;
-}
-
-/* ===========================================================================
-   Rewind a gzfile back to the beginning.
-*/
-
-local int gz_rewind (gz_stream *s)
-{
-    TRYFREE(s->msg);
-
-#ifdef UNIX
-    lseek(s->file, 0L, SEEK_SET);
-#else
-    fseek(s->file, 0L, SEEK_SET);
-#endif
-    inflateReset(&(s->stream));
-    s->stream.next_in = Z_NULL;
-    s->stream.next_out = Z_NULL;
-    s->stream.avail_in = s->stream.avail_out = 0;
-    s->z_err = Z_OK;
-    s->z_eof = 0;
-    s->crc = crc32(0L, Z_NULL, 0);
-    s->msg = NULL;
-    s->position = 0;
-    s->stream.next_in = s->inbuf;
-
-    s->stream.avail_out = Z_BUFSIZE;
-
-    check_header(s);		/* skip the .gz header */
-    return 1;
-}
-
-/* ===========================================================================
-     Opens a gzip (.gz) file for reading or writing.
-*/
-ErtsGzFile erts_gzopen (path, mode)
-    const char *path;
-    const char *mode;
-{
-    return gz_open (path, mode);
-}
-
-
-/* ===========================================================================
-     Read a byte from a gz_stream; update next_in and avail_in. Return EOF
-   for end of file.
-   IN assertion: the stream s has been successfully opened for reading.
-*/
-local int get_byte(s)
-    gz_stream *s;
-{
-    if (s->z_eof) return EOF;
-    if (s->stream.avail_in == 0) {
-#ifdef UNIX
-	ssize_t res;
-	errno = 0;
-	res = ERTS_GZREAD(s->file, s->inbuf, Z_BUFSIZE);
-	if (res == 0) {
-	    s->stream.avail_in = 0;
-	    s->z_eof = 1;
-	    return EOF;
-	} else if (res < 0) {
-	    s->stream.avail_in = 0;
-	    s->z_eof = 1;
-	    s->z_err = Z_ERRNO;
-	    return EOF;
-	} else {
-	    s->stream.avail_in = (uInt) res;
-	}
-#else
-	errno = 0;
-	s->stream.avail_in = ERTS_GZREAD(s->file, s->inbuf, Z_BUFSIZE);
-	if (s->stream.avail_in == 0) {
-	    s->z_eof = 1;
-	    if (s->file && ferror(s->file))
-		s->z_err = Z_ERRNO;
-	    return EOF;
-	}
-#endif
-	s->stream.next_in = s->inbuf;
-    }
-    s->stream.avail_in--;
-    return *(s->stream.next_in)++;
-}
-
-/* ===========================================================================
-      Check the gzip header of a gz_stream opened for reading. Set the stream
-    mode to transparent if the gzip magic header is not present; set s->err
-    to Z_DATA_ERROR if the magic header is present but the rest of the header
-    is incorrect.
-    IN assertion: the stream s has already been created sucessfully;
-       s->stream.avail_in is zero for the first time, but may be non-zero
-       for concatenated .gz files.
-*/
-local void check_header(s)
-    gz_stream *s;
-{
-    int method; /* method byte */
-    int flags;  /* flags byte */
-    uInt len;
-    int c;
-
-    /* Check the gzip magic header */
-    for (len = 0; len < 2; len++) {
-	c = get_byte(s);
-	if (c != gz_magic[len]) {
-	    if (len != 0) s->stream.avail_in++, s->stream.next_in--;
-	    if (c != EOF) {
-		s->stream.avail_in++, s->stream.next_in--;
-		s->transparent = 1;
-	    }
-	    s->z_err = s->stream.avail_in != 0 ? Z_OK : Z_STREAM_END;
-	    return;
-	}
-    }
-    method = get_byte(s);
-    flags = get_byte(s);
-    if (method != Z_DEFLATED || (flags & RESERVED) != 0) {
-	s->z_err = Z_DATA_ERROR;
-	return;
-    }
-
-    /* Discard time, xflags and OS code: */
-    for (len = 0; len < 6; len++) (void)get_byte(s);
-
-    if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */
-	len  =  (uInt)get_byte(s);
-	len += ((uInt)get_byte(s))<<8;
-	/* len is garbage if EOF but the loop below will quit anyway */
-	while (len-- != 0 && get_byte(s) != EOF) ;
-    }
-    if ((flags & ORIG_NAME) != 0) { /* skip the original file name */
-	while ((c = get_byte(s)) != 0 && c != EOF) ;
-    }
-    if ((flags & COMMENT) != 0) {   /* skip the .gz file comment */
-	while ((c = get_byte(s)) != 0 && c != EOF) ;
-    }
-    if ((flags & HEAD_CRC) != 0) {  /* skip the header crc */
-	for (len = 0; len < 2; len++) (void)get_byte(s);
-    }
-    s->z_err = s->z_eof ? Z_DATA_ERROR : Z_OK;
-}
-
- /* ===========================================================================
- * Cleanup then free the given gz_stream. Return a zlib error code.
-   Try freeing in the reverse order of allocations.
- */
-local int destroy (s)
-    gz_stream *s;
-{
-    int err = Z_OK;
-
-    if (!s) return Z_STREAM_ERROR;
-
-    TRYFREE(s->msg);
-
-    if (s->stream.state != NULL) {
-       if (s->mode == 'w') {
-           err = deflateEnd(&(s->stream));
-       } else if (s->mode == 'r') {
-           err = inflateEnd(&(s->stream));
-       }
-    }
-#ifdef UNIX
-    if (s->file != -1 && close(s->file)) {
-        err = Z_ERRNO;
-    }
-#else
-    if (s->file != NULL && fclose(s->file)) {
-        err = Z_ERRNO;
-    }
-#endif
-    if (s->z_err < 0) err = s->z_err;
-
-    TRYFREE(s->inbuf);
-    TRYFREE(s->outbuf);
-    TRYFREE(s->path);
-    TRYFREE(s);
-    return err;
-}
-
-/* ===========================================================================
-     Reads the given number of uncompressed bytes from the compressed file.
-   gzread returns the number of bytes actually read (0 for end of file).
-*/
-int
-erts_gzread(ErtsGzFile file, voidp buf, unsigned len)
-{
-    gz_stream *s = (gz_stream*)file;
-    Bytef *start = buf; /* starting point for crc computation */
-    Byte  *next_out; /* == stream.next_out but not forced far (for MSDOS) */
-
-    if (s == NULL || s->mode != 'r') return Z_STREAM_ERROR;
-
-    if (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO) return -1;
-    if (s->z_err == Z_STREAM_END) return 0;  /* EOF */
-
-    s->stream.next_out = next_out = buf;
-    s->stream.avail_out = len;
-
-    while (s->stream.avail_out != 0) {
-
-	if (s->transparent) {
-	    /* Copy first the lookahead bytes: */
-	    uInt n = s->stream.avail_in;
-	    if (n > s->stream.avail_out) n = s->stream.avail_out;
-	    if (n > 0) {
-		zmemcpy(s->stream.next_out, s->stream.next_in, n);
-		next_out += n;
-		s->stream.next_out = next_out;
-		s->stream.next_in   += n;
-		s->stream.avail_out -= n;
-		s->stream.avail_in  -= n;
-	    }
-	    if (s->stream.avail_out > 0) {
-		s->stream.avail_out -= ERTS_GZREAD(s->file, next_out,
-						   s->stream.avail_out);
-	    }
-	    len -= s->stream.avail_out;
-	    s->stream.total_in  += (uLong)len;
-	    s->stream.total_out += (uLong)len;
-            if (len == 0) s->z_eof = 1;
-	    s->position += (int)len;
-	    return (int)len;
-	}
-        if (s->stream.avail_in == 0 && !s->z_eof) {
-#ifdef UNIX
-	    ssize_t res;
-	    errno = 0;
-	    res = ERTS_GZREAD(s->file, s->inbuf, Z_BUFSIZE);
-	    if (res == 0) {
-		s->stream.avail_in = 0;
-		s->z_eof = 1;
-		return EOF;
-	    } else if (res < 0) {
-		s->stream.avail_in = 0;
-		s->z_eof = 1;
-		s->z_err = Z_ERRNO;
-		return EOF;
-	    } else {
-		s->stream.avail_in = (uInt) res;
-	    }
-#else
-	    errno = 0;
-            s->stream.avail_in = ERTS_GZREAD(s->file, s->inbuf, Z_BUFSIZE);
-            if (s->stream.avail_in == 0) {
-                s->z_eof = 1;
-		if (s->file && ferror(s->file)) {
-		    s->z_err = Z_ERRNO;
-		    break;
-		}
-            }
-#endif
-            s->stream.next_in = s->inbuf;
-        }
-        s->z_err = inflate(&(s->stream), Z_NO_FLUSH);
-
-	if (s->z_err == Z_STREAM_END) {
-	    /* Check CRC and original size */
-	    s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start));
-	    start = s->stream.next_out;
-
-	    if (getLong(s) != s->crc) {
-		s->z_err = Z_DATA_ERROR;
-	    } else {
-	        (void)getLong(s);
-                /* The uncompressed length returned by above getlong() may
-                 * be different from s->stream.total_out) in case of
-		 * concatenated .gz files. Check for such files:
-		 */
-		check_header(s);
-		if (s->z_err == Z_OK) {
-		    uLong total_in = s->stream.total_in;
-		    uLong total_out = s->stream.total_out;
-
-		    inflateReset(&(s->stream));
-		    s->stream.total_in = total_in;
-		    s->stream.total_out = total_out;
-		    s->crc = crc32(0L, Z_NULL, 0);
-		}
-	    }
-	}
-	if (s->z_err != Z_OK || s->z_eof) break;
-    }
-    s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start));
-
-    s->position += (int)(len - s->stream.avail_out);
-
-    return (int)(len - s->stream.avail_out);
-}
-
-/* ===========================================================================
-     Writes the given number of uncompressed bytes into the compressed file.
-   gzwrite returns the number of bytes actually written (0 in case of error).
-*/
-int
-erts_gzwrite(ErtsGzFile file, voidp buf, unsigned len)
-{
-    gz_stream *s = (gz_stream*)file;
-
-    if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR;
-
-    s->stream.next_in = buf;
-    s->stream.avail_in = len;
-
-    while (s->stream.avail_in != 0) {
-
-        if (s->stream.avail_out == 0) {
-
-            s->stream.next_out = s->outbuf;
-            if (ERTS_GZWRITE(s->file, s->outbuf, Z_BUFSIZE) != Z_BUFSIZE) {
-                s->z_err = Z_ERRNO;
-                break;
-            }
-            s->stream.avail_out = Z_BUFSIZE;
-        }
-        s->z_err = deflate(&(s->stream), Z_NO_FLUSH);
-        if (s->z_err != Z_OK) break;
-    }
-    s->position += (int)(len - s->stream.avail_in);
-    return (int)(len - s->stream.avail_in);
-}
-
-/*
- * For use by Erlang file driver.
- *
- * XXX Limitations:
- *  - SEEK_END is not allowed (length of file is not known).
- *  - When writing, only forward seek is supported.
- */
-
-int
-erts_gzseek(ErtsGzFile file, int offset, int whence)
-{
-    int pos;
-    gz_stream* s = (gz_stream *) file;
-
-    switch (whence) {
-    case EFILE_SEEK_SET: whence = SEEK_SET; break;
-    case EFILE_SEEK_CUR: whence = SEEK_CUR; break;
-    case EFILE_SEEK_END: whence = SEEK_END; break;
-    default:
-	errno = EINVAL;
-	return -1;
-    }
-
-    if (s == NULL) {
-	errno = EINVAL;
-	return -1;
-    }
-    if (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO) {
-	errno = EIO;
-	return -1;
-    }
-
-    switch (whence) {
-    case SEEK_SET: pos = offset; break;
-    case SEEK_CUR: pos = s->position+offset; break;
-    case SEEK_END: 
-    default:
-      errno = EINVAL; return -1;
-    }
-
-    if (pos == s->position) {
-	return pos;
-    }
-
-    if (pos < s->position) {
-	if (s->mode == 'w') {
-	    errno = EINVAL;
-	    return -1;
-	}
-	gz_rewind(s);
-    }
-
-    while (s->position < pos) {
-	char buf[512];
-	int n;
-	int save_pos = s->position;
-
-	n = pos - s->position;
-	if (n > sizeof(buf))
-	    n = sizeof(buf);
-
-	if (s->mode == 'r') {
-	    erts_gzread(file, buf, n);
-	} else {
-	    memset(buf, '\0', n);
-	    erts_gzwrite(file, buf, n);
-	}
-	if (save_pos == s->position) break;
-    }
-
-    return s->position;
-}
-
-/* ===========================================================================
-     Flushes all pending output into the compressed file. The parameter
-   flush is as in the deflate() function.
-     gzflush should be called only when strictly necessary because it can
-   degrade compression.
-*/
-int
-erts_gzflush(ErtsGzFile file, int flush)
-{
-    uInt len;
-    int done = 0;
-    gz_stream *s = (gz_stream*)file;
-
-    if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR;
-
-    s->stream.avail_in = 0; /* should be zero already anyway */
-
-    for (;;) {
-        len = Z_BUFSIZE - s->stream.avail_out;
-
-        if (len != 0) {
-            if ((uInt)ERTS_GZWRITE(s->file, s->outbuf, len) != len) {
-                s->z_err = Z_ERRNO;
-                return Z_ERRNO;
-            }
-            s->stream.next_out = s->outbuf;
-            s->stream.avail_out = Z_BUFSIZE;
-        }
-        if (done) break;
-        s->z_err = deflate(&(s->stream), flush);
-
-        /* deflate has finished flushing only when it hasn't used up
-         * all the available space in the output buffer: 
-         */
-        done = (s->stream.avail_out != 0 || s->z_err == Z_STREAM_END);
- 
-        if (s->z_err != Z_OK && s->z_err != Z_STREAM_END) break;
-    }
-#ifndef UNIX
-    fflush(s->file);
-#endif
-    return  s->z_err == Z_STREAM_END ? Z_OK : s->z_err;
-}
-
-/* ===========================================================================
-   Reads a long in LSB order from the given gz_stream. Sets 
-*/
-local uLong getLong (s)
-    gz_stream *s;
-{
-    uLong x = (uLong)get_byte(s);
-    int c;
-
-    x += ((uLong)get_byte(s))<<8;
-    x += ((uLong)get_byte(s))<<16;
-    c = get_byte(s);
-    if (c == EOF) s->z_err = Z_DATA_ERROR;
-    x += ((uLong)c)<<24;
-    return x;
-}
-
-/* ===========================================================================
-     Flushes all pending output if necessary, closes the compressed file
-   and deallocates all the (de)compression state.
-*/
-int
-erts_gzclose(ErtsGzFile file)
-{
-    int err;
-    gz_stream *s = (gz_stream*)file;
-
-    if (s == NULL) return Z_STREAM_ERROR;
-
-    if (s->mode == 'w') {
-        err = erts_gzflush (file, Z_FINISH);
-        if (err != Z_OK) return s->destroy(s);
-    }
-    return s->destroy(s);
-}
-
-
 /* ===========================================================================
    Uncompresses the buffer given and returns a pointer to a binary.
    If the buffer was not compressed with gzip, the buffer contents
diff --git a/erts/emulator/drivers/common/gzio.h b/erts/emulator/drivers/common/gzio.h
index ee0ebe7bd8..e331b5208b 100644
--- a/erts/emulator/drivers/common/gzio.h
+++ b/erts/emulator/drivers/common/gzio.h
@@ -20,13 +20,5 @@
 
 #include "zlib.h"
 
-typedef struct erts_gzFile* ErtsGzFile;
-
-ErtsGzFile erts_gzopen (const char *path, const char *mode);
-int erts_gzread(ErtsGzFile file, voidp buf, unsigned len);
-int erts_gzwrite(ErtsGzFile file, voidp buf, unsigned len);
-int erts_gzseek(ErtsGzFile, int, int);
-int erts_gzflush(ErtsGzFile file, int flush);
-int erts_gzclose(ErtsGzFile file);
 ErlDrvBinary* erts_gzinflate_buffer(char*, uLong);
 ErlDrvBinary* erts_gzdeflate_buffer(char*, uLong);
diff --git a/erts/emulator/drivers/common/inet_drv.c b/erts/emulator/drivers/common/inet_drv.c
index 554c48059f..4294fb4f46 100644
--- a/erts/emulator/drivers/common/inet_drv.c
+++ b/erts/emulator/drivers/common/inet_drv.c
@@ -63,6 +63,20 @@
 #include <sys/un.h>
 #endif
 
+#ifdef HAVE_SENDFILE
+#if defined(__linux__) || (defined(__sun) && defined(__SVR4))
+    #include <sys/sendfile.h>
+#elif defined(__FreeBSD__) || defined(__DragonFly__)
+    /* Need to define __BSD_VISIBLE in order to expose prototype of sendfile */
+    #define __BSD_VISIBLE 1
+    #include <sys/socket.h>
+#endif
+#endif
+
+#if defined(__APPLE__) && defined(__MACH__) && !defined(__DARWIN__)
+    #define __DARWIN__ 1
+#endif
+
 /* All platforms fail on malloc errors. */
 #define FATAL_MALLOC
 
@@ -701,6 +715,7 @@ static size_t my_strnlen(const char *s, size_t maxlen)
 #define TCP_REQ_RECV           42
 #define TCP_REQ_UNRECV         43
 #define TCP_REQ_SHUTDOWN       44
+#define TCP_REQ_SENDFILE       45
 /* UDP and SCTP requests */
 #define PACKET_REQ_RECV        60 /* Common for UDP and SCTP         */
 /* #define SCTP_REQ_LISTEN       61 MERGED Different from TCP; not for UDP */
@@ -723,6 +738,7 @@ static size_t my_strnlen(const char *s, size_t maxlen)
 #define TCP_ADDF_DELAYED_ECONNRESET 128 /* An ECONNRESET error occurred on send or shutdown */
 #define TCP_ADDF_SHUTDOWN_WR_DONE 256 /* A shutdown(sock, SHUT_WR) or SHUT_RDWR was made */
 #define TCP_ADDF_LINGER_ZERO 	  512 /* Discard driver queue on port close */
+#define TCP_ADDF_SENDFILE         1024 /* Send from an fd instead of the driver queue */
 
 /* *_REQ_* replies */
 #define INET_REP_ERROR       0
@@ -1136,7 +1152,6 @@ static int        packet_inet_init(void);
 static void       packet_inet_stop(ErlDrvData);
 static void       packet_inet_command(ErlDrvData, char*, ErlDrvSizeT);
 static void       packet_inet_drv_input(ErlDrvData data, ErlDrvEvent event);
-static void	  packet_inet_drv_output(ErlDrvData data, ErlDrvEvent event);
 static ErlDrvData udp_inet_start(ErlDrvPort, char* command);
 #ifdef HAVE_SCTP
 static ErlDrvData sctp_inet_start(ErlDrvPort, char* command);
@@ -1161,7 +1176,7 @@ static struct erl_drv_entry udp_inet_driver_entry =
     NULL, 
 #else
     packet_inet_drv_input,
-    packet_inet_drv_output,
+    NULL,
 #endif
     "udp_inet",
     NULL,
@@ -1196,7 +1211,7 @@ static struct erl_drv_entry sctp_inet_driver_entry =
     NULL, 
 #else
     packet_inet_drv_input,
-    packet_inet_drv_output,
+    NULL,
 #endif
     "sctp_inet",
     NULL,
@@ -1236,6 +1251,21 @@ typedef struct {
     inet_async_multi_op *multi_first;/* NULL == no multi-accept-queue, op is in ordinary queue */
     inet_async_multi_op *multi_last;
     MultiTimerData *mtd;        /* Timer structures for multiple accept */
+#ifdef HAVE_SENDFILE
+    struct {
+        ErlDrvSizeT ioq_skip;   /* The number of bytes in the queue at the time
+                                 * sendfile was issued, which must be sent
+                                 * before issuing the sendfile call itself. */
+        int dup_file_fd;        /* The file handle to send from; this is
+                                 * duplicated when sendfile is issued to
+                                 * reduce (but not eliminate) the impact of a
+                                 * nasty race, so we have to remember to close
+                                 * it. */
+        Uint64 bytes_sent;
+        Uint64 offset;
+        Uint64 length;
+    } sendfile;
+#endif
 } tcp_descriptor;
 
 /* send function */
@@ -1246,6 +1276,8 @@ static int tcp_deliver(tcp_descriptor* desc, int len);
 
 static int tcp_shutdown_error(tcp_descriptor* desc, int err);
 
+static int tcp_inet_sendfile(tcp_descriptor* desc);
+
 static int tcp_inet_output(tcp_descriptor* desc, HANDLE event);
 static int tcp_inet_input(tcp_descriptor* desc, HANDLE event);
 
@@ -1262,7 +1294,6 @@ typedef struct {
 
 
 static int packet_inet_input(udp_descriptor* udesc, HANDLE event);
-static int packet_inet_output(udp_descriptor* udesc, HANDLE event);
 #endif
 
 /* convert descriptor pointer to inet_descriptor pointer */
@@ -1331,6 +1362,9 @@ static ErlDrvTermData am_ipv6_v6only;
 static ErlDrvTermData am_netns;
 static ErlDrvTermData am_bind_to_device;
 #endif
+#ifdef HAVE_SENDFILE
+static ErlDrvTermData am_sendfile;
+#endif
 
 static char str_eafnosupport[] = "eafnosupport";
 static char str_einval[] = "einval";
@@ -3877,6 +3911,10 @@ static int inet_init()
     INIT_ATOM(https);
     INIT_ATOM(scheme);
 
+#ifdef HAVE_SENDFILE
+    INIT_ATOM(sendfile);
+#endif
+
     /* add TCP, UDP and SCTP drivers */
     add_driver_entry(&tcp_inet_driver_entry);
 #ifdef HAVE_UDP
@@ -9272,6 +9310,13 @@ static void tcp_inet_stop(ErlDrvData e)
  * will be freed through tcp_inet_stop later on. */
 static void tcp_desc_close(tcp_descriptor* desc)
 {
+#ifdef HAVE_SENDFILE
+    if(desc->tcp_add_flags & TCP_ADDF_SENDFILE) {
+        desc->tcp_add_flags &= ~TCP_ADDF_SENDFILE;
+        close(desc->sendfile.dup_file_fd);
+    }
+#endif
+
     tcp_clear_input(desc);
     tcp_clear_output(desc);
 
@@ -9610,6 +9655,60 @@ static ErlDrvSSizeT tcp_inet_ctl(ErlDrvData e, unsigned int cmd,
 	    return ctl_reply(INET_REP_OK, NULL, 0, rbuf, rsize);
 	}
     }
+
+    case TCP_REQ_SENDFILE: {
+#ifdef HAVE_SENDFILE
+        const ErlDrvSizeT required_len =
+            sizeof(desc->sendfile.dup_file_fd) +
+            sizeof(Uint64) * 2;
+
+        int raw_file_fd;
+
+        DEBUGF(("tcp_inet_ctl(%ld): SENDFILE\r\n", (long)desc->inet.port));
+
+        if (len != required_len) {
+            return ctl_error(EINVAL, rbuf, rsize);
+        } else if (!IS_CONNECTED(INETP(desc))) {
+            return ctl_error(ENOTCONN, rbuf, rsize);
+        }
+
+        sys_memcpy(&raw_file_fd, buf, sizeof(raw_file_fd));
+        buf += sizeof(raw_file_fd);
+
+        desc->sendfile.dup_file_fd = dup(raw_file_fd);
+
+        if(desc->sendfile.dup_file_fd == -1) {
+            return ctl_error(errno, rbuf, rsize);
+        }
+
+        desc->sendfile.offset = get_int64(buf);
+        buf += sizeof(Uint64);
+
+        desc->sendfile.length = get_int64(buf);
+        buf += sizeof(Uint64);
+
+        ASSERT(desc->sendfile.offset >= 0);
+        ASSERT(desc->sendfile.length >= 0);
+
+        desc->sendfile.ioq_skip = driver_sizeq(desc->inet.port);
+        desc->sendfile.bytes_sent = 0;
+
+        desc->inet.caller = driver_caller(desc->inet.port);
+        desc->tcp_add_flags |= TCP_ADDF_SENDFILE;
+
+        /* See if we can finish sending without selecting & rescheduling. */
+        tcp_inet_sendfile(desc);
+
+        if(desc->sendfile.length > 0) {
+            sock_select(INETP(desc), FD_WRITE, 1);
+        }
+
+        return ctl_reply(INET_REP_OK, NULL, 0, rbuf, rsize);
+#else
+        return ctl_error(ENOTSUP, rbuf, rsize);
+#endif
+    }
+
     default:
 	DEBUGF(("tcp_inet_ctl(%ld): %u\r\n", (long)desc->inet.port, cmd)); 
 	return inet_ctl(INETP(desc), cmd, buf, len, rbuf, rsize);
@@ -9749,12 +9848,27 @@ static void tcp_inet_commandv(ErlDrvData e, ErlIOVec* ev)
 static void tcp_inet_flush(ErlDrvData e)
 {
     tcp_descriptor* desc = (tcp_descriptor*)e;
-    if (!(desc->inet.event_mask & FD_WRITE)) {
-	/* Discard send queue to avoid hanging port (OTP-7615) */
-	tcp_clear_output(desc);
+    int discard_output;
+
+    /* Discard send queue to avoid hanging port (OTP-7615) */
+    discard_output = !(desc->inet.event_mask & FD_WRITE);
+
+    discard_output |= desc->tcp_add_flags & TCP_ADDF_LINGER_ZERO;
+
+#ifdef HAVE_SENDFILE
+    /* The old file driver aborted when it was stopped during sendfile, so
+     * we'll clear the flag and discard all output. */
+    if(desc->tcp_add_flags & TCP_ADDF_SENDFILE) {
+        desc->tcp_add_flags &= ~TCP_ADDF_SENDFILE;
+        close(desc->sendfile.dup_file_fd);
+
+        discard_output = 1;
+    }
+#endif
+
+    if (discard_output) {
+        tcp_clear_output(desc);
     }
-    if (desc->tcp_add_flags & TCP_ADDF_LINGER_ZERO)
-	tcp_clear_output(desc);
 }
 
 static void tcp_inet_process_exit(ErlDrvData e, ErlDrvMonitor *monitorp) 
@@ -10649,7 +10763,9 @@ static int tcp_sendv(tcp_descriptor* desc, ErlIOVec* ev)
 	ev->size += h_len;
     }
 
-    if ((sz = driver_sizeq(ix)) > 0) {
+    sz = driver_sizeq(ix);
+
+    if ((desc->tcp_add_flags & TCP_ADDF_SENDFILE) || sz > 0) {
 	driver_enqv(ix, ev, 0);
 	if (sz+ev->size >= desc->high) {
 	    DEBUGF(("tcp_sendv(%ld): s=%d, sender forced busy\r\n",
@@ -10743,8 +10859,9 @@ static int tcp_send(tcp_descriptor* desc, char* ptr, ErlDrvSizeT len)
 
     inet_output_count(INETP(desc), len+h_len);
 
+    sz = driver_sizeq(ix);
 
-    if ((sz = driver_sizeq(ix)) > 0) {
+    if ((desc->tcp_add_flags & TCP_ADDF_SENDFILE) || sz > 0) {
 	if (h_len > 0)
 	    driver_enq(ix, buf, h_len);
 	driver_enq(ix, ptr, len);
@@ -10834,6 +10951,246 @@ static void tcp_inet_drv_input(ErlDrvData data, ErlDrvEvent event)
     (void)tcp_inet_input((tcp_descriptor*)data, (HANDLE)event);
 }
 
+#ifdef HAVE_SENDFILE
+static int tcp_sendfile_completed(tcp_descriptor* desc) {
+    ErlDrvTermData spec[LOAD_PORT_CNT + LOAD_TUPLE_CNT * 2 +
+        LOAD_ATOM_CNT * 2 + LOAD_UINT_CNT * 2];
+    Uint32 sent_low, sent_high;
+    int i;
+
+    desc->tcp_add_flags &= ~TCP_ADDF_SENDFILE;
+    close(desc->sendfile.dup_file_fd);
+
+    /* While we flushed the output queue prior to sending the file, we've
+     * deferred clearing busy status until now as there's no point in doing so
+     * while we still have a file to send.
+     *
+     * The watermark is checked since more data may have been added while we
+     * were sending the file. */
+
+    if (driver_sizeq(desc->inet.port) <= desc->low) {
+        if (IS_BUSY(INETP(desc))) {
+            desc->inet.caller = desc->inet.busy_caller;
+            desc->inet.state &= ~INET_F_BUSY;
+
+            set_busy_port(desc->inet.port, 0);
+
+            /* if we have a timer then cancel and send ok to client */
+            if (desc->busy_on_send) {
+                driver_cancel_timer(desc->inet.port);
+                desc->busy_on_send = 0;
+            }
+
+            inet_reply_ok(INETP(desc));
+        }
+    }
+
+    if (driver_sizeq(desc->inet.port) == 0) {
+        sock_select(INETP(desc), FD_WRITE, 0);
+        send_empty_out_q_msgs(INETP(desc));
+
+        if (desc->tcp_add_flags & TCP_ADDF_PENDING_SHUTDOWN) {
+            tcp_shutdown_async(desc);
+        }
+    }
+
+    sent_low = ((Uint64)desc->sendfile.bytes_sent >> 0) & 0xFFFFFFFF;
+    sent_high = ((Uint64)desc->sendfile.bytes_sent >> 32) & 0xFFFFFFFF;
+
+    i = LOAD_ATOM(spec, 0, am_sendfile);
+    i = LOAD_PORT(spec, i, desc->inet.dport);
+    i = LOAD_ATOM(spec, i, am_ok);
+    i = LOAD_UINT(spec, i, sent_low);
+    i = LOAD_UINT(spec, i, sent_high);
+    i = LOAD_TUPLE(spec, i, 3);
+    i = LOAD_TUPLE(spec, i, 3);
+
+    ASSERT(i == sizeof(spec)/sizeof(*spec));
+
+    return erl_drv_output_term(desc->inet.dport, spec, i);
+}
+
+static int tcp_sendfile_aborted(tcp_descriptor* desc, int socket_error) {
+    ErlDrvTermData spec[LOAD_PORT_CNT + LOAD_TUPLE_CNT * 2 + LOAD_ATOM_CNT * 3];
+    int i;
+
+    /* We don't clean up sendfile state here, as that's done in tcp_desc_close
+     * following normal error handling. All we do here is report the failure. */
+
+    i = LOAD_ATOM(spec, 0, am_sendfile);
+    i = LOAD_PORT(spec, i, desc->inet.dport);
+    i = LOAD_ATOM(spec, i, am_error);
+
+    switch (socket_error) {
+    case ECONNRESET:
+    case ENOTCONN:
+    case EPIPE:
+        i = LOAD_ATOM(spec, i, am_closed);
+        break;
+    default:
+        i = LOAD_ATOM(spec, i, error_atom(socket_error));
+    }
+
+    i = LOAD_TUPLE(spec, i, 2);
+    i = LOAD_TUPLE(spec, i, 3);
+
+    ASSERT(i == sizeof(spec)/sizeof(*spec));
+
+    return erl_drv_output_term(desc->inet.dport, spec, i);
+}
+
+static int tcp_inet_sendfile(tcp_descriptor* desc) {
+    ErlDrvPort ix = desc->inet.port;
+    int result = 0;
+    ssize_t n;
+
+    DEBUGF(("tcp_inet_sendfile(%ld) {s=%d\r\n", (long)ix, desc->inet.s));
+
+    /* If there was any data in the queue by the time sendfile was issued,
+     * we'll need to skip it first. Note that we don't clear busy status until
+     * we're finished sending the file. */
+    while (desc->sendfile.ioq_skip > 0) {
+        ssize_t bytes_to_send;
+        SysIOVec* iov;
+        int vsize;
+
+        ASSERT(driver_sizeq(ix) >= desc->sendfile.ioq_skip);
+
+        if ((iov = driver_peekq(ix, &vsize)) == NULL) {
+            ERTS_INTERNAL_ERROR("ioq empty when sendfile.ioq_skip > 0");
+        }
+
+        bytes_to_send = MIN(desc->sendfile.ioq_skip, iov[0].iov_len);
+        n = sock_send(desc->inet.s, iov[0].iov_base, bytes_to_send, 0);
+
+        if (!IS_SOCKET_ERROR(n)) {
+            desc->sendfile.ioq_skip -= n;
+            driver_deq(ix, n);
+        } else if (sock_errno() == ERRNO_BLOCK) {
+#ifdef __WIN32__
+            desc->inet.send_would_block = 1;
+#endif
+            goto done;
+        } else if (sock_errno() != EINTR) {
+            goto socket_error;
+        }
+    }
+
+    while (desc->sendfile.length > 0) {
+        /* For some reason the maximum ssize_t cannot be used as the max size.
+         * 1GB seems to work on all platforms */
+        const Sint64 SENDFILE_CHUNK_SIZE = ((1UL << 30) - 1);
+
+        ssize_t bytes_to_send = MIN(SENDFILE_CHUNK_SIZE, desc->sendfile.length);
+        off_t offset = desc->sendfile.offset;
+
+#if defined(__linux__)
+        n = sendfile(desc->inet.s, desc->sendfile.dup_file_fd, &offset,
+            bytes_to_send);
+#elif defined(__FreeBSD__) || defined(__DragonFly__) || defined(__DARWIN__)
+        {
+            off_t bytes_sent;
+            int error;
+
+    #if defined(__DARWIN__)
+            bytes_sent = bytes_to_send;
+
+            error = sendfile(desc->sendfile.dup_file_fd, desc->inet.s, offset,
+                &bytes_sent, NULL, 0);
+            n = bytes_sent;
+    #else
+            error = sendfile(desc->sendfile.dup_file_fd, desc->inet.s, offset,
+                bytes_to_send, NULL, &bytes_sent, 0);
+            n = bytes_sent;
+    #endif
+
+            if(error < 0) {
+                /* EAGAIN/EINTR report partial success by setting bytes_sent,
+                 * so we have to skip error handling if nonzero, and skip EOF
+                 * handling if zero, as it's possible that we didn't manage to
+                 * send anything at all before being interrupted by a
+                 * signal. */
+                if((errno != EAGAIN && errno != EINTR) || bytes_sent == 0) {
+                    n = -1;
+                }
+            }
+        }
+#elif defined(__sun) && defined(__SVR4) && defined(HAVE_SENDFILEV)
+        {
+            sendfilevec_t sfvec[1];
+            size_t bytes_sent;
+            ssize_t error;
+
+            sfvec[0].sfv_fd = desc->sendfile.dup_file_fd;
+            sfvec[0].sfv_len = bytes_to_send;
+            sfvec[0].sfv_off = offset;
+            sfvec[0].sfv_flag = 0;
+
+            error = sendfilev(desc->inet.s, sfvec, 1, &bytes_sent);
+            n = bytes_sent;
+
+            if(error < 0) {
+                if(errno == EINVAL) {
+                    /* On some solaris versions (I've seen it on SunOS 5.10),
+                     * using a sfv_len larger than the filesize will result in
+                     * a (-1 && errno == EINVAL). We translate this to a
+                     * successful send of the data.*/
+                } else {
+                    /* EAGAIN/EINTR behavior is identical to *BSD. */
+                    if((errno != EAGAIN && errno != EINTR) || bytes_sent == 0) {
+                        n = -1;
+                    }
+                }
+            }
+        }
+#else
+        #error "Unsupported sendfile syscall; update configure test."
+#endif
+
+        if (n > 0) {
+            desc->sendfile.bytes_sent += n;
+            desc->sendfile.offset += n;
+            desc->sendfile.length -= n;
+        } else if (n == 0) {
+            /* EOF. */
+            desc->sendfile.length = 0;
+            break;
+        } else if (IS_SOCKET_ERROR(n) && sock_errno() != EINTR) {
+            if (sock_errno() != ERRNO_BLOCK) {
+                goto socket_error;
+            }
+
+#ifdef __WIN32__
+            desc->inet.send_would_block = 1;
+#endif
+            break;
+        }
+    }
+
+    if (desc->sendfile.length == 0) {
+        tcp_sendfile_completed(desc);
+    }
+
+    goto done;
+
+socket_error: {
+        int socket_errno = sock_errno();
+
+        DEBUGF(("tcp_inet_sendfile(%ld): send errno = %d (errno %d)\r\n",
+            (long)desc->inet.port, socket_errno, errno));
+
+        result = tcp_send_error(desc, socket_errno);
+        tcp_sendfile_aborted(desc, socket_errno);
+
+        goto done;
+    }
+
+done:
+    DEBUGF(("tcp_inet_sendfile(%ld) }\r\n", (long)desc->inet.port));
+    return result;
+}
+#endif /* HAVE_SENDFILE */
+
 /* socket ready for ouput:
 ** 1. INET_STATE_CONNECTING => non block connect ?
 ** 2. INET_STATE_CONNECTED  => write output
@@ -10894,7 +11251,14 @@ static int tcp_inet_output(tcp_descriptor* desc, HANDLE event)
 	async_ok(INETP(desc));
     }
     else if (IS_CONNECTED(INETP(desc))) {
-	for (;;) {
+
+#ifdef HAVE_SENDFILE
+        if(desc->tcp_add_flags & TCP_ADDF_SENDFILE) {
+            return tcp_inet_sendfile(desc);
+        }
+#endif
+
+        for (;;) {
 	    int vsize;
 	    ssize_t n;
 	    SysIOVec* iov;
@@ -11300,24 +11664,20 @@ static ErlDrvSSizeT packet_inet_ctl(ErlDrvData e, unsigned int cmd, char* buf,
 		 (desc->sfamily, &remote, &buf, &len)) != NULL)
 	        return ctl_xerror(xerror, rbuf, rsize);
 	
-	    sock_select(desc, FD_CONNECT, 1);
 	    code = sock_connect(desc->s, &remote.sa, len);
 
 	    if (IS_SOCKET_ERROR(code) && (sock_errno() == EINPROGRESS)) {
 		/* XXX: Unix only -- WinSock would have a different cond! */
-		desc->state = INET_STATE_CONNECTING;
 		if (timeout != INET_INFINITY)
 		    driver_set_timer(desc->port, timeout);
 		enq_async(desc, tbuf, INET_REQ_CONNECT);
+		async_ok(desc);
 	    }
 	    else if (code == 0) { /* OK we are connected */
-		sock_select(desc, FD_CONNECT, 0);
-		desc->state = INET_STATE_CONNECTED;
 		enq_async(desc, tbuf, INET_REQ_CONNECT);
 		async_ok(desc);
 	    }
 	    else {
-		sock_select(desc, FD_CONNECT, 0);
 		return ctl_error(sock_errno(), rbuf, rsize);
 	    }
 	    return ctl_reply(INET_REP_OK, tbuf, 2, rbuf, rsize);
@@ -11832,77 +12192,6 @@ static int packet_inet_input(udp_descriptor* udesc, HANDLE event)
     return count;
 }
 
-static void packet_inet_drv_output(ErlDrvData e, ErlDrvEvent event)
-{
-    (void)  packet_inet_output((udp_descriptor*)e, (HANDLE)event);
-}
-
-/* UDP/SCTP socket ready for output:
-**	This is a Back-End for Non-Block SCTP Connect (INET_STATE_CONNECTING)
-*/
-static int packet_inet_output(udp_descriptor* udesc, HANDLE event)
-{
-    inet_descriptor* desc = INETP(udesc);
-    int ret = 0;
-    ErlDrvPort ix = desc->port;
-
-    DEBUGF(("packet_inet_output(%ld) {s=%d\r\n", 
-	    (long)desc->port, desc->s));
-
-    if (desc->state == INET_STATE_CONNECTING) {
-	sock_select(desc, FD_CONNECT, 0);
-
-	driver_cancel_timer(ix);  /* posssibly cancel a timer */
-#ifndef __WIN32__
-	/*
-	 * XXX This is strange.  This *should* work on Windows NT too,
-	 * but doesn't.  An bug in Winsock 2.0 for Windows NT?
-	 *
-	 * See "Unix Netwok Programming", W.R.Stevens, p 412 for a
-	 * discussion about Unix portability and non blocking connect.
-	 */
-
-#ifndef SO_ERROR
-	{
-	    int sz = sizeof(desc->remote);
-	    int code = sock_peer(desc->s,
-				 (struct sockaddr*) &desc->remote, &sz);
-
-	    if (IS_SOCKET_ERROR(code)) {
-		desc->state = INET_STATE_OPEN;  /* restore state */
-		ret =  async_error(desc, sock_errno());
-		goto done;
-	    }
-	}
-#else
-	{
-	    int error = 0;	/* Has to be initiated, we check it */
-	    unsigned int sz = sizeof(error);   /* even if we get -1 */
-	    int code = sock_getopt(desc->s, SOL_SOCKET, SO_ERROR, 
-				   (void *)&error, &sz);
-
-	    if ((code < 0) || error) {
-		desc->state = INET_STATE_OPEN;  /* restore state */
-		ret = async_error(desc, error);
-		goto done;
-	    }
-	}
-#endif /* SO_ERROR */
-#endif /* !__WIN32__ */
-
-	desc->state = INET_STATE_CONNECTED;
-	async_ok(desc);
-    }
-    else {
-	sock_select(desc,FD_CONNECT,0);
-
-	DEBUGF(("packet_inet_output(%ld): bad state: %04x\r\n", 
-		(long)desc->port, desc->state));
-    }
- done:
-    DEBUGF(("packet_inet_output(%ld) }\r\n", (long)desc->port));
-    return ret;
-}
 #endif
 
 /*---------------------------------------------------------------------------*/
diff --git a/erts/emulator/drivers/unix/ttsl_drv.c b/erts/emulator/drivers/unix/ttsl_drv.c
index 2a508b02eb..7355df6059 100644
--- a/erts/emulator/drivers/unix/ttsl_drv.c
+++ b/erts/emulator/drivers/unix/ttsl_drv.c
@@ -892,8 +892,8 @@ static void ttysl_from_tty(ErlDrvData ttysl_data, ErlDrvEvent fd)
 		tpos = 0;
 	    }
 	}
-    } else {
-        DEBUGLOG(("ttysl_from_tty: driver failure in read(%d,..) = %d\n", (int)(SWord)fd, i)); 
+    } else if (errno != EAGAIN && errno != EWOULDBLOCK) {
+        DEBUGLOG(("ttysl_from_tty: driver failure in read(%d,..) = %d (errno = %d)\n", (int)(SWord)fd, i, errno));
 	driver_failure(ttysl_port, -1);
     }
 }
diff --git a/erts/emulator/drivers/unix/unix_efile.c b/erts/emulator/drivers/unix/unix_efile.c
deleted file mode 100644
index 33e4d75ef7..0000000000
--- a/erts/emulator/drivers/unix/unix_efile.c
+++ /dev/null
@@ -1,1102 +0,0 @@
-/*
- * %CopyrightBegin%
- *
- * Copyright Ericsson AB 1997-2017. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * %CopyrightEnd%
- */
-/*
- * Purpose: Provides file and directory operations for Unix.
- */
-#ifdef HAVE_CONFIG_H
-#  include "config.h"
-#endif
-#if defined(HAVE_POSIX_FALLOCATE) && !defined(__sun) && !defined(__sun__)
-#define _XOPEN_SOURCE 600
-#endif
-#if !defined(_GNU_SOURCE) && defined(HAVE_LINUX_FALLOC_H)
-#define _GNU_SOURCE
-#endif
-#include "sys.h"
-#include "erl_driver.h"
-#include "erl_efile.h"
-#include <utime.h>
-#ifdef HAVE_UNISTD_H
-#include <unistd.h>
-#endif
-#ifdef HAVE_SYS_UIO_H
-#include <sys/types.h>
-#include <sys/uio.h>
-#if defined(HAVE_SENDFILE) && (defined(__FreeBSD__) || defined(__DragonFly__))
-/* Need to define __BSD_VISIBLE in order to expose prototype of sendfile */
-#define __BSD_VISIBLE 1
-#include <sys/socket.h>
-#endif
-#endif
-#if defined(HAVE_SENDFILE) && (defined(__linux__) || (defined(__sun) && defined(__SVR4)))
-#include <sys/sendfile.h>
-#endif
-
-#if defined(__APPLE__) && defined(__MACH__) && !defined(__DARWIN__)
-#define __DARWIN__ 1
-#endif
-
-#if defined(__DARWIN__) || defined(HAVE_LINUX_FALLOC_H) || defined(HAVE_POSIX_FALLOCATE)
-#include <fcntl.h>
-#endif
-
-#ifdef HAVE_LINUX_FALLOC_H
-#include <linux/falloc.h>
-#endif
-
-#ifdef SUNOS4
-#  define getcwd(buf, size) getwd(buf)
-#endif
-
-/* Find a definition of MAXIOV, that is used in the code later. */
-#if defined IOV_MAX
-#define MAXIOV IOV_MAX
-#elif defined UIO_MAXIOV
-#define MAXIOV UIO_MAXIOV
-#else
-#define MAXIOV 16
-#endif
-
-
-/*
- * Macros for testing file types.
- */
-
-#define ISDIR(st) (S_ISDIR((st).st_mode))
-#define ISREG(st) (S_ISREG((st).st_mode))
-#define ISDEV(st) (S_ISCHR((st).st_mode) || S_ISBLK((st).st_mode))
-#define ISLNK(st) (S_ISLNK((st).st_mode))
-#ifdef NO_UMASK
-#define FILE_MODE 0644
-#define DIR_MODE  0755
-#else
-#define FILE_MODE 0666
-#define DIR_MODE  0777
-#endif
-
-#define IS_DOT_OR_DOTDOT(s) \
-    (s[0] == '.' && (s[1] == '\0' || (s[1] == '.' && s[2] == '\0')))
-
-static int check_error(int result, Efile_error* errInfo);
-
-static int
-check_error(int result, Efile_error *errInfo)
-{
-    if (result < 0) {
-	errInfo->posix_errno = errInfo->os_errno = errno;
-	return 0;
-    }
-    return 1;
-}
-
-int
-efile_init() {
-   return 1;
-}
-
-int
-efile_mkdir(Efile_error* errInfo,	/* Where to return error codes. */
-	    char* name)			/* Name of directory to create. */
-{
-#ifdef NO_MKDIR_MODE
-    return check_error(mkdir(name), errInfo);
-#else
-    return check_error(mkdir(name, DIR_MODE), errInfo);
-#endif
-}
-
-int
-efile_rmdir(Efile_error* errInfo,	/* Where to return error codes. */
-	    char* name)			/* Name of directory to delete. */
-{
-    if (rmdir(name) == 0) {
-	return 1;
-    }
-    if (errno == ENOTEMPTY) {
-	errno = EEXIST;
-    }
-    if (errno == EEXIST) {
-	int saved_errno = errno;
-	struct stat file_stat;
-	struct stat cwd_stat;
-
-	/*
-	 *  The error code might be wrong if this is the current directory.
-	 */
-
-	if (stat(name, &file_stat) == 0 && stat(".", &cwd_stat) == 0 &&
-	    file_stat.st_ino == cwd_stat.st_ino &&
-	    file_stat.st_dev == cwd_stat.st_dev) {
-	    saved_errno = EINVAL;
-	}
-	errno = saved_errno;
-    }
-    return check_error(-1, errInfo);
-}
-
-int
-efile_delete_file(Efile_error* errInfo,	/* Where to return error codes. */
-		  char* name)		/* Name of file to delete. */
-{
-    if (unlink(name) == 0) {
-	return 1;
-    }
-    if (errno == EISDIR) {	/* Linux sets the wrong error code. */
-	errno = EPERM;
-    }
-    return check_error(-1, errInfo);
-}
-
-/*
- *---------------------------------------------------------------------------
- *
- *      Changes the name of an existing file or directory, from src to dst.
- *	If src and dst refer to the same file or directory, does nothing
- *	and returns success.  Otherwise if dst already exists, it will be
- *	deleted and replaced by src subject to the following conditions:
- *	    If src is a directory, dst may be an empty directory.
- *	    If src is a file, dst may be a file.
- *	In any other situation where dst already exists, the rename will
- *	fail.  
- *
- * Results:
- *	If the directory was successfully created, returns 1.
- *	Otherwise the return value is 0 and errno is set to
- *	indicate the error.  Some possible values for errno are:
- *
- *	EACCES:     src or dst parent directory can't be read and/or written.
- *	EEXIST:	    dst is a non-empty directory.
- *	EINVAL:	    src is a root directory or dst is a subdirectory of src.
- *	EISDIR:	    dst is a directory, but src is not.
- *	ENOENT:	    src doesn't exist, or src or dst is "".
- *	ENOTDIR:    src is a directory, but dst is not.  
- *	EXDEV:	    src and dst are on different filesystems.
- *	
- * Side effects:
- *	The implementation of rename may allow cross-filesystem renames,
- *	but the caller should be prepared to emulate it with copy and
- *	delete if errno is EXDEV.
- *
- *---------------------------------------------------------------------------
- */
-
-int
-efile_rename(Efile_error* errInfo,	/* Where to return error codes. */
-	     char* src,		        /* Original name. */
-	     char* dst)			/* New name. */
-{
-    if (rename(src, dst) == 0) {
-	return 1;
-    }
-    if (errno == ENOTEMPTY) {
-	errno = EEXIST;
-    }
-#if defined (sparc)
-    /*
-     * SunOS 4.1.4 reports overwriting a non-empty directory with a
-     * directory as EINVAL instead of EEXIST (first rule out the correct
-     * EINVAL result code for moving a directory into itself).  Must be
-     * conditionally compiled because realpath() is only defined on SunOS.
-     */
-
-    if (errno == EINVAL) {
-	char srcPath[MAXPATHLEN], dstPath[MAXPATHLEN];
-	DIR *dirPtr;
-	struct dirent *dirEntPtr;
-
-#ifdef PURIFY
-	memset(srcPath, '\0', sizeof(srcPath));
-	memset(dstPath, '\0', sizeof(dstPath));
-#endif
-
-	if ((realpath(src, srcPath) != NULL)
-		&& (realpath(dst, dstPath) != NULL)
-		&& (strncmp(srcPath, dstPath, strlen(srcPath)) != 0)) {
-	    dirPtr = opendir(dst);
-	    if (dirPtr != NULL) {
-		while ((dirEntPtr = readdir(dirPtr)) != NULL) {
-		    if ((strcmp(dirEntPtr->d_name, ".") != 0) &&
-			    (strcmp(dirEntPtr->d_name, "..") != 0)) {
-			errno = EEXIST;
-			closedir(dirPtr);
-			return check_error(-1, errInfo);
-		    }
-		}
-		closedir(dirPtr);
-	    }
-	}
-	errno = EINVAL;
-    }
-#endif	/* sparc */
-
-    if (strcmp(src, "/") == 0) {
-	/*
-	 * Alpha reports renaming / as EBUSY and Linux reports it as EACCES,
-	 * instead of EINVAL.
-	 */
-	 
-	errno = EINVAL;
-    }
-
-    /*
-     * DEC Alpha OSF1 V3.0 returns EACCES when attempting to move a
-     * file across filesystems and the parent directory of that file is
-     * not writable.  Most other systems return EXDEV.  Does nothing to
-     * correct this behavior.
-     */
-
-    return check_error(-1, errInfo);
-}
-
-int
-efile_chdir(Efile_error* errInfo,   /* Where to return error codes. */
-	    char* name)		    /* Name of directory to make current. */
-{
-    return check_error(chdir(name), errInfo);
-}
-
-
-int
-efile_getdcwd(Efile_error* errInfo,	/* Where to return error codes. */
-	      int drive,		/* 0 - current, 1 - A, 2 - B etc. */
-	      char* buffer,		/* Where to return the current 
-					   directory. */
-	      size_t size)		/* Size of buffer. */
-{
-    if (drive == 0) {
-	if (getcwd(buffer, size) == NULL)
-	    return check_error(-1, errInfo);
-	
-#ifdef SIMSPARCSOLARIS
-	/* We get "host:" prepended to the dirname - remove!. */
-	{
-	  int i = 0;
-	  int j = 0;
-	  while ((buffer[i] != ':') && (buffer[i] != '\0')) i++;
-	  if (buffer[i] == ':') {
-	    i++;
-	    while ((buffer[j++] = buffer[i++]) != '\0');
-	  }
-	}
-#endif	      
-	return 1;
-    }
-
-    /*
-     * Drives other than 0 is not supported on Unix.
-     */
-
-    errno = ENOTSUP;
-    return check_error(-1, errInfo);
-}
-
-int
-efile_readdir(Efile_error* errInfo,	/* Where to return error codes. */
-	      char* name,		/* Name of directory to open. */
-	      EFILE_DIR_HANDLE* p_dir_handle,	/* Pointer to directory 
-						   handle of
-						   open directory.*/
-	      char* buffer,		/* Pointer to buffer for 
-					   one filename. */
-	      size_t *size)		/* in-out Size of buffer, length
-					   of name. */
-{
-    DIR *dp;			/* Pointer to directory structure. */
-    struct dirent* dirp;	/* Pointer to directory entry. */
-
-    /*
-     * If this is the first call, we must open the directory.
-     */
-
-    if (*p_dir_handle == NULL) {
-	dp = opendir(name);
-	if (dp == NULL)
-	    return check_error(-1, errInfo);
-	*p_dir_handle = (EFILE_DIR_HANDLE) dp;
-    }
-
-    /*
-     * Retrieve the name of the next file using the directory handle.
-     */
-
-    dp = *((DIR **)((void *)p_dir_handle));
-    for (;;) {
-	dirp = readdir(dp);
-	if (dirp == NULL) {
-	    closedir(dp);
-	    return 0;
-	}
-	if (IS_DOT_OR_DOTDOT(dirp->d_name))
-	    continue;
-	buffer[0] = '\0';
-	strncat(buffer, dirp->d_name, (*size)-1);
-	*size = strlen(dirp->d_name);
-	return 1;
-    }
-}
-
-int
-efile_openfile(Efile_error* errInfo,	/* Where to return error codes. */
-	       char* name,		/* Name of directory to open. */
-	       int flags,		/* Flags to user for opening. */
-	       int* pfd,		/* Where to store the file 
-					   descriptor. */
-	       Sint64 *pSize)		/* Where to store the size of the 
-					   file. */
-{
-    struct stat statbuf;
-    int fd;
-    int mode;			/* Open mode. */
-
-    switch (flags & (EFILE_MODE_READ|EFILE_MODE_WRITE)) {
-    case EFILE_MODE_READ:
-	mode = O_RDONLY;
-	break;
-    case EFILE_MODE_WRITE:
-	if (flags & EFILE_NO_TRUNCATE)
-	    mode = O_WRONLY | O_CREAT;
-	else
-	    mode = O_WRONLY | O_CREAT | O_TRUNC;
-	break;
-    case EFILE_MODE_READ_WRITE:
-	mode = O_RDWR | O_CREAT;
-	break;
-    default:
-	errno = EINVAL;
-	return check_error(-1, errInfo);
-    }
-
-    if (flags & EFILE_MODE_APPEND) {
-	mode &= ~O_TRUNC;
-	mode |= O_APPEND;
-    }
-    if (flags & EFILE_MODE_EXCL) {
-	mode |= O_EXCL;
-    }
-    if (flags & EFILE_MODE_SYNC) {
-#ifdef O_SYNC
-	mode |= O_SYNC;
-#else
-	errno = ENOTSUP;
-	return check_error(-1, errInfo);
-#endif
-    }
-
-#ifdef HAVE_FSTAT
-    while (((fd = open(name, mode, FILE_MODE)) < 0) && (errno == EINTR));
-    if (!check_error(fd, errInfo)) return 0;
-#endif
-
-    if (
-#ifdef HAVE_FSTAT
-        fstat(fd, &statbuf) < 0
-#else
-        stat(name, &statbuf) < 0
-#endif
-        ) {
-        /* statbuf is undefined: if the caller depends on it,
-           i.e. invoke_read_file(), fail the call immediately */
-        if (pSize && flags == EFILE_MODE_READ) {
-            check_error(-1, errInfo);
-#ifdef HAVE_FSTAT
-            efile_closefile(fd);
-#endif
-            return 0;
-        }
-    }
-    else if (! ISREG(statbuf)) {
-        struct stat nullstatbuf;
-	/*
-	 * For UNIX only, here is some ugly code to allow
-	 * /dev/null to be opened as a file.
-	 */
-        if ( (stat("/dev/null", &nullstatbuf) < 0)
-             || (statbuf.st_ino != nullstatbuf.st_ino)
-             || (statbuf.st_dev != nullstatbuf.st_dev) ) {
-#ifdef HAVE_FSTAT
-            efile_closefile(fd);
-#endif
-	    errno = EISDIR;
-	    return check_error(-1, errInfo);
-        }
-    }
-
-#ifndef HAVE_FSTAT
-    while (((fd = open(name, mode, FILE_MODE)) < 0) && (errno == EINTR));
-    if (!check_error(fd, errInfo)) return 0;
-#endif
-
-    *pfd = fd;
-    if (pSize) *pSize = statbuf.st_size;
-    return 1;
-}
-
-int 
-efile_may_openfile(Efile_error* errInfo, char *name) {
-    struct stat statbuf;	/* Information about the file */
-    int result;
-    
-    result = stat(name, &statbuf);
-    if (!check_error(result, errInfo))
-	return 0;
-    if (!ISREG(statbuf)) {
-	errno = EISDIR;
-	return check_error(-1, errInfo);
-    }
-    return 1;
-}
-
-void
-efile_closefile(int fd)
-{
-    close(fd);
-}
-
-int
-efile_fdatasync(Efile_error *errInfo, /* Where to return error codes. */
-	    int fd)               /* File descriptor for file to sync data. */
-{
-#if defined(HAVE_FDATASYNC) && !defined(__DARWIN__)
-    return check_error(fdatasync(fd), errInfo);
-#else
-    return efile_fsync(errInfo, fd);
-#endif
-}
-
-int
-efile_fsync(Efile_error *errInfo, /* Where to return error codes. */
-	    int fd)               /* File descriptor for file to sync. */
-{
-#ifdef NO_FSYNC
-  undefined fsync /* XXX: Really? */
-#else
-#if defined(__DARWIN__) && defined(F_FULLFSYNC)
-    return check_error(fcntl(fd, F_FULLFSYNC), errInfo);
-#else
-    return check_error(fsync(fd), errInfo);
-#endif /* __DARWIN__ */
-#endif /* NO_FSYNC */
-}
-
-int
-efile_fileinfo(Efile_error* errInfo, Efile_info* pInfo, 
-	       char* name, int info_for_link)
-{
-    struct stat statbuf;	/* Information about the file */
-    int result;
-
-    if (info_for_link) {
-	result = lstat(name, &statbuf);
-    } else {
-	result = stat(name, &statbuf);
-    }	
-    if (!check_error(result, errInfo)) {
-	return 0;
-    }
-
-#if SIZEOF_OFF_T == 4
-    pInfo->size_high = 0;
-#else
-    pInfo->size_high = (Uint32)(statbuf.st_size >> 32);
-#endif
-    pInfo->size_low = (Uint32)statbuf.st_size;
-
-#ifdef NO_ACCESS
-    /* Just look at read/write access for owner. */
-
-    pInfo->access = ((statbuf.st_mode >> 6) & 07) >> 1;
-
-#else
-    pInfo->access = FA_NONE;
-    if (access(name, R_OK) == 0)
-	pInfo->access |= FA_READ;
-    if (access(name, W_OK) == 0)
-	pInfo->access |= FA_WRITE;
-
-#endif	
-
-    if (ISDEV(statbuf))
-	pInfo->type = FT_DEVICE;
-    else if (ISDIR(statbuf))
-	pInfo->type = FT_DIRECTORY;
-    else if (ISREG(statbuf))
-	pInfo->type = FT_REGULAR;
-    else if (ISLNK(statbuf))
-	pInfo->type = FT_SYMLINK;
-    else
-	pInfo->type = FT_OTHER;
-
-    pInfo->accessTime   = (Sint64)statbuf.st_atime;
-    pInfo->modifyTime   = (Sint64)statbuf.st_mtime;
-    pInfo->cTime        = (Sint64)statbuf.st_ctime;
-
-    pInfo->mode         = statbuf.st_mode;
-    pInfo->links        = statbuf.st_nlink;
-    pInfo->major_device = statbuf.st_dev;
-    pInfo->minor_device = statbuf.st_rdev;
-    pInfo->inode        = statbuf.st_ino;
-    pInfo->uid          = statbuf.st_uid;
-    pInfo->gid          = statbuf.st_gid;
-
-    return 1;
-}
-
-int
-efile_write_info(Efile_error *errInfo, Efile_info *pInfo, char *name)
-{
-    struct utimbuf tval;
-
-    /*
-     * On some systems chown will always fail for a non-root user unless
-     * POSIX_CHOWN_RESTRICTED is not set.  Others will succeed as long as 
-     * you don't try to chown a file to someone besides youself.
-     */
-
-    if (chown(name, pInfo->uid, pInfo->gid) && errno != EPERM) {
-	return check_error(-1, errInfo);
-    }
-
-    if (pInfo->mode != -1) {
-	mode_t newMode = pInfo->mode & (S_ISUID | S_ISGID |
-					S_IRWXU | S_IRWXG | S_IRWXO);
-	if (chmod(name, newMode)) {
-	    newMode &= ~(S_ISUID | S_ISGID);
-	    if (chmod(name, newMode)) {
-		return check_error(-1, errInfo);
-	    }
-	}
-    }
-
-    tval.actime  = (time_t)pInfo->accessTime;
-    tval.modtime = (time_t)pInfo->modifyTime;
-
-    return check_error(utime(name, &tval), errInfo);
-}
-
-
-int
-efile_write(Efile_error* errInfo,	/* Where to return error codes. */
-	    int flags,			/* Flags given when file was 
-					   opened. */
-	    int fd,			/* File descriptor to write to. */
-	    char* buf,			/* Buffer to write. */
-	    size_t count)		/* Number of bytes to write. */
-{
-    ssize_t written;			/* Bytes written in last operation. */
-
-    while (count > 0) {
-	if ((written = write(fd, buf, count)) < 0) {
-	    if (errno != EINTR)
-		return check_error(-1, errInfo);
-	    else
-		written = 0;
-	}
-	ASSERT(written <= count);
-	buf += written;
-	count -= written;
-    }
-    return 1;
-}
-
-int
-efile_writev(Efile_error* errInfo,   /* Where to return error codes */
-	     int flags,              /* Flags given when file was
-				      * opened */
-	     int fd,                 /* File descriptor to write to */
-	     SysIOVec* iov,          /* Vector of buffer structs.
-				      * The structs may be changed i.e.
-				      * due to incomplete writes */
-	     int iovcnt)             /* Number of structs in vector */
-{
-    int cnt = 0;                     /* Buffers so far written */
-
-    ASSERT(iovcnt >= 0);
-    
-    while (cnt < iovcnt) {
-	if ((! iov[cnt].iov_base) || (iov[cnt].iov_len <= 0)) {
-	    /* Empty buffer - skip */
-	    cnt++;
-	} else { /* Non-empty buffer */
-	    ssize_t w;                   /* Bytes written in this call */
-#ifdef HAVE_WRITEV
-	    int b = iovcnt - cnt;        /* Buffers to write */
-	    /* Use as many buffers as MAXIOV allows */
-	    if (b > MAXIOV)
-		b = MAXIOV;
-	    if (b > 1) {
-		do {
-		    w = writev(fd, &iov[cnt], b);
-		} while (w < 0 && errno == EINTR);
-		if (w < 0 && errno == EINVAL) {
-		    goto single_write;
-		}
-	    } else
-	    single_write:
-		/* Degenerated io vector - use regular write */
-#endif
-		{
-		    do {
-			size_t iov_len = iov[cnt].iov_len;
-			size_t limit = 1024*1024*1024; /* 1GB */
-			if (iov_len > limit) {
-			    iov_len = limit;
-			}
-			w = write(fd, iov[cnt].iov_base, iov_len);
-		    } while (w < 0 && errno == EINTR);
-		    ASSERT(w <= iov[cnt].iov_len ||
-			   (w == -1 && errno != EINTR));
-		}
-	    if (w < 0) return check_error(-1, errInfo);
-	    /* Move forward to next buffer to write */
-	    for (; cnt < iovcnt && w > 0; cnt++) {
-		if (iov[cnt].iov_base && iov[cnt].iov_len > 0) {
-		    if (w < iov[cnt].iov_len) {
-			/* Adjust the buffer for next write */
-			iov[cnt].iov_len -= w;
-			iov[cnt].iov_base = ((char *)iov[cnt].iov_base) + w;
-			w = 0;
-			break;
-		    } else {
-			w -= iov[cnt].iov_len;
-		    }
-		}
-	    }
-	    ASSERT(w == 0);
-	} /* else Non-empty buffer */
-    } /* while (cnt< iovcnt) */
-    return 1;
-}
-
-int
-efile_read(Efile_error* errInfo,     /* Where to return error codes. */
-	   int flags,		     /* Flags given when file was opened. */
-	   int fd,		     /* File descriptor to read from. */
-	   char* buf,		     /* Buffer to read into. */
-	   size_t count,	     /* Number of bytes to read. */
-	   size_t *pBytesRead)	     /* Where to return number of 
-					bytes read. */
-{
-    ssize_t n;
-
-    for (;;) {
-	if ((n = read(fd, buf, count)) >= 0)
-	    break;
-	else if (errno != EINTR)
-	    return check_error(-1, errInfo);
-    }
-    *pBytesRead = (size_t) n;
-    return 1;
-}
-
-
-/* pread() and pwrite()                                                   */
-/* Some unix systems, notably Solaris has these syscalls                  */
-/* It is especially nice for i.e. the dets module to have support         */
-/* for this, even if the underlying OS dosn't support it, it is           */
-/* reasonably easy to work around by first calling seek, and then         */
-/* calling read().                                                        */
-/* This later strategy however changes the file pointer, which pread()    */
-/* does not do. We choose to ignore this and say that the location        */
-/* of the file pointer is undefined after a call to any of the p functions*/
-
-
-int
-efile_pread(Efile_error* errInfo,     /* Where to return error codes. */
-	    int fd,		      /* File descriptor to read from. */
-	    Sint64 offset,            /* Offset in bytes from BOF. */
-	    char* buf,		      /* Buffer to read into. */
-	    size_t count,	      /* Number of bytes to read. */
-	    size_t *pBytesRead)	      /* Where to return 
-					 number of bytes read. */
-{
-#if defined(HAVE_PREAD) && defined(HAVE_PWRITE)
-    ssize_t n;
-    off_t off = (off_t) offset;
-    if (off != offset) {
-	errno = EINVAL;
-	return check_error(-1, errInfo);
-    }
-    for (;;) {
-	if ((n = pread(fd, buf, count, offset)) >= 0)
-	    break;
-	else if (errno != EINTR)
-	    return check_error(-1, errInfo);
-    }
-    *pBytesRead = (size_t) n;
-    return 1;
-#else
-    {
-	int res = efile_seek(errInfo, fd, offset, EFILE_SEEK_SET, NULL);
-	if (res) {
-	    return efile_read(errInfo, 0, fd, buf, count, pBytesRead);
-	} else {
-	    return res;
-	}
-    }
-#endif
-}
-
-
-
-int
-efile_pwrite(Efile_error* errInfo,  /* Where to return error codes. */
-	     int fd,		    /* File descriptor to write to. */
-	     char* buf,		    /* Buffer to write. */
-	     size_t count,	    /* Number of bytes to write. */
-	     Sint64 offset)	    /* where to write it */
-{ 
-#if defined(HAVE_PREAD) && defined(HAVE_PWRITE)
-    ssize_t written;		    /* Bytes written in last operation. */
-    off_t off = (off_t) offset;
-    if (off != offset) {
-	errno = EINVAL;
-	return check_error(-1, errInfo);
-    }
-    
-    while (count > 0) {
-	if ((written = pwrite(fd, buf, count, offset)) < 0) {
-	    if (errno != EINTR)
-		return check_error(-1, errInfo);
-	    else
-		written = 0;
-	}
-	ASSERT(written <= count);
-	buf += written;
-	count -= written;
-	offset += written;
-    }
-    return 1;
-#else  /* For unix systems that don't support pread() and pwrite() */    
-    {
-	int res = efile_seek(errInfo, fd, offset, EFILE_SEEK_SET, NULL);
-	
-	if (res) {
-	    return efile_write(errInfo, 0, fd, buf, count);
-	} else {
-	    return res;
-	}
-    }
-#endif
-}
-
-
-int
-efile_seek(Efile_error* errInfo,      /* Where to return error codes. */
-	   int fd,                    /* File descriptor to do the seek on. */
-	   Sint64 offset,             /* Offset in bytes from the given 
-					 origin. */ 
-	   int origin,                /* Origin of seek (SEEK_SET, SEEK_CUR,
-				         SEEK_END). */ 
-	   Sint64 *new_location)      /* Resulting new location in file. */
-{
-    off_t off, result;
-
-    switch (origin) {
-    case EFILE_SEEK_SET: origin = SEEK_SET; break;
-    case EFILE_SEEK_CUR: origin = SEEK_CUR; break;
-    case EFILE_SEEK_END: origin = SEEK_END; break;
-    default:
-	errno = EINVAL;
-	return check_error(-1, errInfo);
-    }
-    off = (off_t) offset;
-    if (off != offset) {
-	errno = EINVAL;
-	return check_error(-1, errInfo);
-    }
-    
-    errno = 0;
-    result = lseek(fd, off, origin);
-
-    /*
-     * Note that the man page for lseek (on SunOs 5) says:
-     * 
-     * "if fildes is a remote file  descriptor  and  offset  is
-     * negative,  lseek()  returns  the  file pointer even if it is
-     * negative."
-     */
-
-    if (result < 0 && errno == 0)
-	errno = EINVAL;
-    if (result < 0)
-	return check_error(-1, errInfo);
-    if (new_location) {
-	*new_location = result;
-    }
-    return 1;
-}
-
-
-int
-efile_truncate_file(Efile_error* errInfo, int *fd, int flags)
-{
-#ifndef NO_FTRUNCATE
-    off_t offset;
-
-    return check_error((offset = lseek(*fd, 0, 1)) >= 0 &&
-		       ftruncate(*fd, offset) == 0 ? 1 : -1,
-		       errInfo);
-#else
-    return 1;
-#endif
-}
-
-int
-efile_readlink(Efile_error* errInfo, char* name, char* buffer, size_t size)
-{
-    int len;
-    ASSERT(size > 0);
-    len = readlink(name, buffer, size-1);
-    if (len == -1) {
-	return check_error(-1, errInfo);
-    }
-    buffer[len] = '\0';
-    return 1;
-}
-
-int
-efile_altname(Efile_error* errInfo, char* name, char* buffer, size_t size)
-{
-    errno = ENOTSUP;
-    return check_error(-1, errInfo);
-}
-
-int
-efile_link(Efile_error* errInfo, char* old, char* new)
-{
-    return check_error(link(old, new), errInfo);
-}
-
-int
-efile_symlink(Efile_error* errInfo, char* old, char* new)
-{
-    return check_error(symlink(old, new), errInfo);
-}
-
-int
-efile_fadvise(Efile_error* errInfo, int fd, Sint64 offset,
-		  Sint64 length, int advise)
-{
-#ifdef HAVE_POSIX_FADVISE
-    return check_error(posix_fadvise(fd, offset, length, advise), errInfo);
-#else
-    return check_error(0, errInfo);
-#endif
-}
-
-#ifdef HAVE_SENDFILE
-/* For some reason the maximum size_t cannot be used as the max size
-   3GB seems to work on all platforms */
-#define SENDFILE_CHUNK_SIZE ((1UL << 30) -1)
-
-/*
- * sendfile: The implementation of the sendfile system call varies
- * a lot on different *nix platforms so to make the api similar in all
- * we have to emulate some things in linux and play with variables on
- * bsd/darwin.
- *
- * All of the calls will split a command which tries to send more than
- * SENDFILE_CHUNK_SIZE of data at once.
- *
- * On platforms where *nbytes of 0 does not mean the entire file, this is
- * simulated.
- *
- * It could be possible to implement header/trailer in sendfile. Though
- * you would have to emulate it in linux and on BSD/Darwin some complex
- * calculations have to be made when using a non blocking socket to figure
- * out how much of the header/file/trailer was sent in each command.
- *
- * The semantics of the API is this:
- * Return value: 1 if all data was sent and the function does not need to
- * be called again. 0 if an error occures OR if there is more data which
- * has to be sent (EAGAIN or EINTR will be set appropriately)
- *
- * The amount of data written in a call is returned through nbytes.
- *
- */
-
-int
-efile_sendfile(Efile_error* errInfo, int in_fd, int out_fd,
-	       off_t *offset, Uint64 *nbytes, struct t_sendfile_hdtl* hdtl)
-{
-    Uint64 written = 0;
-#if defined(__linux__)
-    ssize_t retval;
-    do {
-      /* check if *nbytes is 0 or greater than chunk size */
-      if (*nbytes == 0 || *nbytes > SENDFILE_CHUNK_SIZE)
-	retval = sendfile(out_fd, in_fd, offset, SENDFILE_CHUNK_SIZE);
-      else
-	retval = sendfile(out_fd, in_fd, offset, *nbytes);
-      if (retval > 0) {
-	written += retval;
-	*nbytes -= retval;
-      }
-    } while (retval == SENDFILE_CHUNK_SIZE);
-    if (written != 0) {
-      /* -1 is not returned by the linux API so we have to simulate it */
-      retval = -1;
-      errno = EAGAIN;
-    }
-#elif defined(__sun) && defined(__SVR4) && defined(HAVE_SENDFILEV)
-    ssize_t retval;
-    size_t len;
-    sendfilevec_t fdrec;
-    fdrec.sfv_fd = in_fd;
-    fdrec.sfv_flag = 0;
-    do {
-      fdrec.sfv_off = *offset;
-      len = 0;
-      /* check if *nbytes is 0 or greater than chunk size */
-      if (*nbytes == 0 || *nbytes > SENDFILE_CHUNK_SIZE)
-	fdrec.sfv_len = SENDFILE_CHUNK_SIZE;
-      else
-	fdrec.sfv_len = *nbytes;
-
-      retval = sendfilev(out_fd, &fdrec, 1, &len);
-
-      if (retval == -1 && errno == EINVAL) {
-          /* On some solaris versions (I've seen it on SunOS 5.10),
-             using a sfv_len larger then a filesize will result in
-             a -1 && errno == EINVAL return. We translate this so
-             a successful send of the data.*/
-          retval = len;
-      }
-
-      if (retval != -1 || errno == EAGAIN || errno == EINTR) {
-        *offset += len;
-	*nbytes -= len;
-	written += len;
-      }
-    } while (len == SENDFILE_CHUNK_SIZE);
-#elif defined(__DARWIN__)
-    int retval;
-    off_t len;
-    do {
-      /* check if *nbytes is 0 or greater than chunk size */
-      if(*nbytes > SENDFILE_CHUNK_SIZE)
-	len = SENDFILE_CHUNK_SIZE;
-      else
-	len = *nbytes;
-      retval = sendfile(in_fd, out_fd, *offset, &len, NULL, 0);
-      if (retval != -1 || errno == EAGAIN || errno == EINTR) {
-        *offset += len;
-	*nbytes -= len;
-	written += len;
-      }
-    } while (len == SENDFILE_CHUNK_SIZE);
-#elif defined(__FreeBSD__) || defined(__DragonFly__)
-    off_t len;
-    int retval;
-    do {
-      if (*nbytes > SENDFILE_CHUNK_SIZE)
-	retval = sendfile(in_fd, out_fd, *offset, SENDFILE_CHUNK_SIZE,
-			  NULL, &len, 0);
-      else
-	retval = sendfile(in_fd, out_fd, *offset, *nbytes, NULL, &len, 0);
-      if (retval != -1 || errno == EAGAIN || errno == EINTR) {
-	*offset += len;
-	*nbytes -= len;
-	written += len;
-      }
-    } while(len == SENDFILE_CHUNK_SIZE);
-#endif
-    *nbytes = written;
-    return check_error(retval, errInfo);
-}
-#endif /* HAVE_SENDFILE */
-
-#ifdef HAVE_POSIX_FALLOCATE
-static int
-call_posix_fallocate(int fd, Sint64 offset, Sint64 length)
-{
-    int ret;
-
-    /*
-     * On Linux and Solaris for example, posix_fallocate() returns
-     * a positive error number on error and it does not set errno.
-     * On FreeBSD however (9.0 at least), it returns -1 on error
-     * and it sets errno.
-     */
-    do {
-        ret = posix_fallocate(fd, (off_t) offset, (off_t) length);
-        if (ret > 0) {
-            errno = ret;
-            ret = -1;
-        }
-    } while (ret != 0 && errno == EINTR);
-
-    return ret;
-}
-#endif /* HAVE_POSIX_FALLOCATE */
-
-int
-efile_fallocate(Efile_error* errInfo, int fd, Sint64 offset, Sint64 length)
-{
-#if defined HAVE_FALLOCATE
-    /* Linux specific, more efficient than posix_fallocate. */
-    int ret;
-
-    do {
-        ret = fallocate(fd, FALLOC_FL_KEEP_SIZE, (off_t) offset, (off_t) length);
-    } while (ret != 0 && errno == EINTR);
-
-#if defined HAVE_POSIX_FALLOCATE
-    /* Fallback to posix_fallocate if available. */
-    if (ret != 0) {
-        ret = call_posix_fallocate(fd, offset, length);
-    }
-#endif
-
-    return check_error(ret, errInfo);
-#elif defined F_PREALLOCATE
-    /* Mac OS X specific, equivalent to posix_fallocate. */
-    int ret;
-    fstore_t fs;
-
-    memset(&fs, 0, sizeof(fs));
-    fs.fst_flags = F_ALLOCATECONTIG;
-    fs.fst_posmode = F_VOLPOSMODE;
-    fs.fst_offset = (off_t) offset;
-    fs.fst_length = (off_t) length;
-
-    ret = fcntl(fd, F_PREALLOCATE, &fs);
-
-    if (-1 == ret) {
-        fs.fst_flags = F_ALLOCATEALL;
-        ret = fcntl(fd, F_PREALLOCATE, &fs);
-
-#if defined HAVE_POSIX_FALLOCATE
-        /* Fallback to posix_fallocate if available. */
-        if (-1 == ret) {
-            ret = call_posix_fallocate(fd, offset, length);
-        }
-#endif
-    }
-
-    return check_error(ret, errInfo);
-#elif defined HAVE_POSIX_FALLOCATE
-    /* Other Unixes, use posix_fallocate if available. */
-    return check_error(call_posix_fallocate(fd, offset, length), errInfo);
-#else
-    errno = ENOTSUP;
-    return check_error(-1, errInfo);
-#endif
-}
diff --git a/erts/emulator/drivers/win32/win_efile.c b/erts/emulator/drivers/win32/win_efile.c
deleted file mode 100644
index 2d366b5833..0000000000
--- a/erts/emulator/drivers/win32/win_efile.c
+++ /dev/null
@@ -1,2058 +0,0 @@
-/*
- * %CopyrightBegin%
- *
- * Copyright Ericsson AB 1997-2016. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * %CopyrightEnd%
- */
-/*
- * Purpose: Provides file and directory operations for Windows.
- */
-
-#include <windows.h>
-#ifdef HAVE_CONFIG_H
-#  include "config.h"
-#endif
-#include "sys.h"
-#include <ctype.h>
-#include <wchar.h>
-#include "erl_efile.h"
-
-#define DBG_TRACE_MASK 0
-/* 1 = file name ops
- * 2 = file descr ops
- * 4 = errors
- * 8 = path name conversion
- */
-#if !DBG_TRACE_MASK
-#  define DBG_TRACE(M,S)
-#  define DBG_TRACE1(M,FMT,A)
-#  define DBG_TRACE2(M,FMT,A,B)
-#else
-#  define DBG_TRACE(M,S) do { if ((M)&DBG_TRACE_MASK) fwprintf(stderr, L"DBG_TRACE %d: %s\r\n", __LINE__, (WCHAR*)(S)); }while(0)
-#  define DBG_TRACE1(M,FMT,A) do { if ((M)&DBG_TRACE_MASK) fwprintf(stderr, L"DBG_TRACE %d: " L##FMT L"\r\n", __LINE__, (A)); }while(0)
-#  define DBG_TRACE2(M,FMT,A,B) do { if ((M)&DBG_TRACE_MASK) fwprintf(stderr, L"DBG_TRACE %d: " L##FMT L"\r\n", __LINE__, (A), (B)); }while(0)
-#endif
-
-/*
- * Microsoft-specific function to map a WIN32 error code to a Posix errno.
- */
-
-#define ISSLASH(a)  ((a) == L'\\' || (a) == L'/')
-#define ISDIR(st) (((st).st_mode&S_IFMT) == S_IFDIR)
-#define ISREG(st) (((st).st_mode&S_IFMT) == S_IFREG)
-
-#define IS_DOT_OR_DOTDOT(s) \
-    ((s)[0] == L'.' && ((s)[1] == L'\0' || ((s)[1] == L'.' && (s)[2] == L'\0')))
-
-#define FILE_SHARE_FLAGS (FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE)
-
-#ifndef INVALID_FILE_ATTRIBUTES
-#define INVALID_FILE_ATTRIBUTES ((DWORD) 0xFFFFFFFF)
-#endif
-
-#define TICKS_PER_SECOND (10000000ULL)
-#define EPOCH_DIFFERENCE (11644473600LL)
-
-#define FILETIME_TO_EPOCH(epoch, ft) \
-    do { \
-	ULARGE_INTEGER ull; \
-	ull.LowPart  = (ft).dwLowDateTime; \
-	ull.HighPart = (ft).dwHighDateTime; \
-	(epoch) = ((ull.QuadPart / TICKS_PER_SECOND) - EPOCH_DIFFERENCE); \
-    } while(0)
-
-#define EPOCH_TO_FILETIME(ft, epoch) \
-    do { \
-	ULARGE_INTEGER ull; \
-	ull.QuadPart = (((epoch) + EPOCH_DIFFERENCE) * TICKS_PER_SECOND); \
-	(ft).dwLowDateTime = ull.LowPart; \
-	(ft).dwHighDateTime = ull.HighPart; \
-    } while(0)
-
-
-static int check_error(int result, Efile_error* errInfo);
-static int set_error(Efile_error* errInfo);
-static int set_os_errno(Efile_error* errInfo, DWORD os_errno);
-static int is_root_unc_name(const WCHAR *path);
-static int extract_root(WCHAR *name);
-static unsigned short dos_to_posix_mode(int attr, const WCHAR *name);
-
-
-struct wpath_tmp_buffer {
-    struct wpath_tmp_buffer* next;
-    WCHAR buffer[1];
-};
-
-typedef struct {
-    Efile_error* errInfo;
-    struct wpath_tmp_buffer* buf_list;
-}Efile_call_state;
-
-static void call_state_init(Efile_call_state* state, Efile_error* errInfo)
-{
-    state->errInfo = errInfo;
-    state->buf_list = NULL;
-}
-static WCHAR* wpath_tmp_alloc(Efile_call_state* state, size_t len)
-{
-    size_t sz = offsetof(struct wpath_tmp_buffer, buffer)
-	+ (len+1)*sizeof(WCHAR);
-    struct wpath_tmp_buffer* p = driver_alloc(sz);
-    p->next = state->buf_list;
-    state->buf_list = p;
-    return p->buffer;
-}
-static void call_state_free(Efile_call_state* state)
-{
-    while(state->buf_list) {
-	struct wpath_tmp_buffer* next = state->buf_list->next;
-	driver_free(state->buf_list);
-	state->buf_list = next;
-    }
-}
-static WCHAR* get_cwd_wpath_tmp(Efile_call_state* state)
-{
-    WCHAR dummy;
-    DWORD size = GetCurrentDirectoryW(0, &dummy);
-    WCHAR* ret = NULL;
-
-    if (size) {
-	ret = wpath_tmp_alloc(state, size);
-	if (!GetCurrentDirectoryW(size, ret)) {
-	    ret = NULL;
-	}
-    }
-    return ret;
-}
-static WCHAR* get_full_wpath_tmp(Efile_call_state* state,
-                                 const WCHAR* file,
-				 WCHAR** file_part,
-				 DWORD extra)
-{
-    WCHAR dummy;
-    DWORD size = GetFullPathNameW(file, 0, &dummy, NULL);
-    WCHAR* ret = NULL;
-
-    if (size) {
-	int ok;
-	ret = wpath_tmp_alloc(state, size + extra);
-	if (file_part) {
-	    ok = (GetFullPathNameW(file, size, ret, file_part) != 0);
-	}
-	else {
-	    ok = (_wfullpath(ret, file, size) != NULL);
-	}
-	if (!ok) {
-	    ret = NULL;
-	}
-    }
-    return ret;
-}
-
-static void ensure_wpath_max(Efile_call_state* state, WCHAR** pathp, size_t max);
-static int do_rmdir(Efile_call_state*, char* name);
-static int do_rename(Efile_call_state*, char* src, char* dst);
-static int do_readdir(Efile_call_state*, char* name, EFILE_DIR_HANDLE*, char* buffer, size_t *size);
-static int do_fileinfo(Efile_call_state*, Efile_info*, char* orig_name, int info_for_link);
-static char* do_readlink(Efile_call_state*, char* name, char* buffer, size_t size);
-static int do_altname(Efile_call_state*, char* orig_name, char* buffer, size_t size);
-
-
-static int errno_map(DWORD last_error) {
-
-    switch (last_error) {
-    case ERROR_SUCCESS:
-	return 0;
-    case ERROR_INVALID_FUNCTION:
-    case ERROR_INVALID_DATA:
-    case ERROR_INVALID_PARAMETER:
-    case ERROR_INVALID_TARGET_HANDLE:
-    case ERROR_INVALID_CATEGORY:
-    case ERROR_NEGATIVE_SEEK:
-	return EINVAL;
-    case ERROR_DIR_NOT_EMPTY:
-	return EEXIST;
-    case ERROR_BAD_FORMAT:
-	return ENOEXEC;
-    case ERROR_PATH_NOT_FOUND:
-    case ERROR_FILE_NOT_FOUND:
-    case ERROR_NO_MORE_FILES:
-	return ENOENT;
-    case ERROR_TOO_MANY_OPEN_FILES:
-	return EMFILE;
-    case ERROR_ACCESS_DENIED:
-    case ERROR_INVALID_ACCESS:
-    case ERROR_CURRENT_DIRECTORY:
-    case ERROR_SHARING_VIOLATION:
-    case ERROR_LOCK_VIOLATION:
-    case ERROR_INVALID_PASSWORD:
-    case ERROR_DRIVE_LOCKED:
-	return EACCES;
-    case ERROR_INVALID_HANDLE:
-	return EBADF;
-    case ERROR_NOT_ENOUGH_MEMORY:
-    case ERROR_OUTOFMEMORY:
-    case ERROR_OUT_OF_STRUCTURES:
-	return ENOMEM;
-    case ERROR_INVALID_DRIVE:
-    case ERROR_BAD_UNIT:
-    case ERROR_NOT_READY:
-    case ERROR_REM_NOT_LIST:
-    case ERROR_DUP_NAME:
-    case ERROR_BAD_NETPATH:
-    case ERROR_NETWORK_BUSY:
-    case ERROR_DEV_NOT_EXIST:
-    case ERROR_BAD_NET_NAME:
-	return ENXIO;
-    case ERROR_NOT_SAME_DEVICE:
-	return EXDEV;
-    case ERROR_WRITE_PROTECT:
-	return EROFS;
-    case ERROR_BAD_LENGTH:
-    case ERROR_BUFFER_OVERFLOW:
-	return E2BIG;
-    case ERROR_SEEK:
-    case ERROR_SECTOR_NOT_FOUND:
-	return ESPIPE;
-    case ERROR_NOT_DOS_DISK:
-	return ENODEV;
-    case ERROR_GEN_FAILURE:
-	return ENODEV;
-    case ERROR_SHARING_BUFFER_EXCEEDED:
-    case ERROR_NO_MORE_SEARCH_HANDLES:
-	return EMFILE;
-    case ERROR_HANDLE_EOF:
-    case ERROR_BROKEN_PIPE:
-	return EPIPE;
-    case ERROR_HANDLE_DISK_FULL:
-    case ERROR_DISK_FULL:
-	return ENOSPC;
-    case ERROR_NOT_SUPPORTED:
-	return ENOTSUP;
-    case ERROR_FILE_EXISTS:
-    case ERROR_ALREADY_EXISTS:
-    case ERROR_CANNOT_MAKE:
-	return EEXIST;
-    case ERROR_ALREADY_ASSIGNED:
-	return EBUSY;
-    case ERROR_NO_PROC_SLOTS:
-	return EAGAIN;
-    case ERROR_CANT_RESOLVE_FILENAME:
-	return EMLINK;
-    case ERROR_PRIVILEGE_NOT_HELD:
-	return EPERM;
-    case ERROR_ARENA_TRASHED:
-    case ERROR_INVALID_BLOCK:
-    case ERROR_BAD_ENVIRONMENT:
-    case ERROR_BAD_COMMAND:
-    case ERROR_CRC:
-    case ERROR_OUT_OF_PAPER:
-    case ERROR_READ_FAULT:
-    case ERROR_WRITE_FAULT:
-    case ERROR_WRONG_DISK:
-    case ERROR_NET_WRITE_FAULT:
-	return EIO;
-    default: /* not to do with files I expect. */
-	return EIO;
-    }	
-}
-
-static int
-check_error(int result, Efile_error* errInfo)
-{
-    if (result < 0) {
-	errInfo->posix_errno = errno;
-	errInfo->os_errno = GetLastError();
-	DBG_TRACE2(4, "ERROR os_error=%d errno=%d @@@@@@@@@@@@@@@@@@@@@@@@@@@@",
-	        errInfo->os_errno, errInfo->posix_errno);
-	return 0;
-    }
-    return 1;
-}
-
-static void
-save_last_error(Efile_error* errInfo)
-{
-    errInfo->posix_errno = errno;
-    errInfo->os_errno = GetLastError();
-    DBG_TRACE2(4, "ERROR os_error=%d errno=%d $$$$$$$$$$$$$$$$$$$$$$$$$$$$$",
-	errInfo->os_errno, errInfo->posix_errno);
-}
-
-
-/*
- * Fills the provided error information structure with information
- * with the error code given by GetLastError() and its corresponding
- * Posix error number.
- *
- * Returns 0.
- */
-
-static int
-set_error(Efile_error* errInfo)
-{
-    set_os_errno(errInfo, GetLastError());
-    return 0;
-}
-
-
-static int
-set_os_errno(Efile_error* errInfo, DWORD os_errno)
-{
-    errInfo->os_errno = os_errno;
-    errInfo->posix_errno = errno_map(os_errno);
-    DBG_TRACE2(4, "ERROR os_error=%d errno=%d ############################",
-	    errInfo->os_errno, errInfo->posix_errno);
-    return 0;
-}
-
-int
-efile_init() {
-   return 1;
-}
-
-/*
- * A writev with Unix semantics, but with Windows arguments 
- */
-static int 
-win_writev(Efile_error* errInfo,
-	   HANDLE fd,                  /* handle to file */
-	   FILE_SEGMENT_ELEMENT iov[], /* array of buffer pointers */
-	   DWORD *size)                /* number of bytes to write */
-{
-    OVERLAPPED ov;
-    ov.Offset = 0L;
-    ov.OffsetHigh = 0L;
-    ov.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
-    if (ov.hEvent == NULL)
-	return set_error(errInfo);
-    if (! write_file_gather(fd, iov, *size, NULL, &ov))
-	return set_error(errInfo);
-    if (WaitForSingleObject(ov.hEvent, INFINITE) != WAIT_OBJECT_0)
-	return set_error(errInfo);
-    if (! GetOverlappedResult(fd, &ov, size, FALSE))
-	return set_error(errInfo);
-    return 1;
-}
-
-
-/* Check '*pathp' and convert it if needed to something that windows will accept.
- * Typically use UNC path with \\?\ prefix if absolute path is longer than 260.
- */
-static void ensure_wpath(Efile_call_state* state, WCHAR** pathp)
-{
-    ensure_wpath_max(state, pathp, MAX_PATH);
-}
-
-static void ensure_wpath_max(Efile_call_state* state, WCHAR** pathp, size_t max)
-{
-    WCHAR* path = *pathp;
-    WCHAR* p;
-    size_t len = wcslen(path);
-    int unc_fixup = 0;
-
-    if (path[0] == 0) {
-	DBG_TRACE(8, L"Let empty path pass through");
-	return;
-    }
-
-    DBG_TRACE1(8,"IN: %s", path);
-
-    if (path[1] == L':' && ISSLASH(path[2])) { /* absolute path */
-	if (len >= max) {
-	    WCHAR *src, *dst;
-
-	    *pathp = wpath_tmp_alloc(state, 4+len+1);
-	    dst = *pathp;
-	    wcscpy(dst, L"\\\\?\\");
-	    for (src=path,dst+=4; *src; src++) {
-		if (*src == L'/') {
-		    if (dst[-1] != L'\\') {
-			*dst++ =  L'\\';
-		    }
-		    /*else ignore redundant slashes */
-		}
-		else
-		    *dst++ = *src;
-	    }
-	    *dst = 0;
-	    unc_fixup = 1;
-	}
-    }
-    else if (!(ISSLASH(path[0]) && ISSLASH(path[1]))) { /* relative path */
-	DWORD cwdLen = GetCurrentDirectoryW(0, NULL);
-	DWORD absLen = cwdLen + 1 + len;
-	if (absLen >= max) {
-	    WCHAR *fullPath = wpath_tmp_alloc(state, 4+4+absLen);
-	    DWORD fullLen;
-
-	    fullLen = GetFullPathNameW(path, 4 + absLen, fullPath+4, NULL);
-	    if (fullLen >= 4+absLen) {
-		*pathp = path;
-		DBG_TRACE2(8,"ensure_wpath FAILED absLen=%u %s", (int)absLen, path);
-		return;
-	    }
-	    /* GetFullPathNameW can return paths longer than MAX_PATH without the \\?\ prefix.
-	     * At least seen on Windows 7. Go figure...
-	     */
-	    if (fullLen >= max && wcsncmp(fullPath+4, L"\\\\?\\", 4) != 0) {
-		wcsncpy(fullPath, L"\\\\?\\", 4);
-		*pathp = fullPath;
-	    }
-	    else {
-		*pathp = fullPath + 4;
-	    }
-	}
-    }
-
-    if (unc_fixup) {
-	WCHAR* endp;
-
-	p = *pathp;
-	len = wcslen(p);
-	endp = p + len;
-	if (len > 4) {
-	    p += 4;
-	    while (*p) {
-		if (p[0] == L'\\' && p[1] == L'.') {
-		    if (p[2] == L'\\' || !p[2]) { /* single dot */
-			wmemmove(p, p+2, (&endp[1] - &p[2]));
-			endp -= 2;
-		    }
-		    else if (p[2] == L'.' && (p[3] == L'\\' || !p[3])) { /* double dot */
-			WCHAR* r;
-			for (r=p-1; *r == L'\\'; --r)
-			    /*skip redundant slashes*/;
-			for (; *r != L'\\'; --r)
-			    /*find start of prev directory*/;
-			if (r < *pathp + 6)
-			    break;
-			wmemmove(r, p+3, (&endp[1] - &p[3]));
-			p = r;
-		    }
-		    else p += 3;
-		}
-		else ++p;
-	    }
-	}
-    }
-    DBG_TRACE1(8,"OUT: %s", *pathp);
-}
-
-int
-efile_mkdir(Efile_error* errInfo,	/* Where to return error codes. */
-	    char* name)			/* Name of directory to create. */
-{
-    Efile_call_state state;
-    WCHAR* wname = (WCHAR*)name;
-    int ret;
-
-    DBG_TRACE(1, name);
-    call_state_init(&state, errInfo);
-    ensure_wpath_max(&state, &wname, 248); /* Yes, 248 limit for normal paths */
-
-    ret = (int) CreateDirectoryW(wname, NULL);
-    if (!ret)
-	set_error(errInfo);
-
-    call_state_free(&state);
-    return ret;
-}
-
-int
-efile_rmdir(Efile_error* errInfo,	/* Where to return error codes. */
-	    char* name)			/* Name of directory to delete. */
-{
-    Efile_call_state state;
-    int ret;
-
-    DBG_TRACE(1, name);
-    call_state_init(&state, errInfo);
-    ret = do_rmdir(&state, name);
-    call_state_free(&state);
-    return ret;
-}
-
-static int do_rmdir(Efile_call_state* state, char* name)
-{
-    OSVERSIONINFO os;
-    DWORD attr;
-    WCHAR *wname = (WCHAR *) name;
-    WCHAR *buffer = NULL;
-
-    ensure_wpath(state, &wname);
-
-    if (RemoveDirectoryW(wname) != FALSE) {
-	return 1;
-    }
-    errno = errno_map(GetLastError());
-    if (errno == EACCES) {
-	attr = GetFileAttributesW(wname);
-	if (attr != (DWORD) -1) {
-	    if ((attr & FILE_ATTRIBUTE_DIRECTORY) == 0) {
-		/* 
-		 * Windows 95 reports calling RemoveDirectory on a file as an 
-		 * EACCES, not an ENOTDIR.
-		 */
-		
-		errno = ENOTDIR;
-		goto end;
-	    }
-
-	    /* 
-	     * Windows 95 reports removing a non-empty directory as
-	     * an EACCES, not an EEXIST.  If the directory is not empty,
-	     * change errno so caller knows what's going on.
-	     */
-
-	    os.dwOSVersionInfoSize = sizeof(os);
-	    GetVersionEx(&os);
-	    if (os.dwPlatformId == VER_PLATFORM_WIN32_WINDOWS) {
-		HANDLE handle;
-		WIN32_FIND_DATAW data;
-		int len = wcslen(wname);
-
-		buffer = wpath_tmp_alloc(state, len + 4);
-		wcscpy(buffer, wname);
-		if (buffer[0] && buffer[len-1] != L'\\' && buffer[len-1] != L'/') {
-		    wcscat(buffer, L"\\");
-		}
-		wcscat(buffer, L"*.*");
-		handle = FindFirstFileW(buffer, &data);
-		if (handle != INVALID_HANDLE_VALUE) {
-		    while (1) {
-			if ((wcscmp(data.cFileName, L".") != 0)
-				&& (wcscmp(data.cFileName, L"..") != 0)) {
-			    /*
-			     * Found something in this directory.
-			     */
-
-			    errno = EEXIST;
-			    break;
-			}
-			if (FindNextFileW(handle, &data) == FALSE) {
-			    break;
-			}
-		    }
-		    FindClose(handle);
-		}
-	    }
-	}
-    }
-
-    if (errno == ENOTEMPTY) {
-	/* 
-	 * Posix allows both EEXIST or ENOTEMPTY, but we'll always
-	 * return EEXIST to allow easy matching in Erlang code.
-	 */
-
-	errno = EEXIST;
-    }
-
- end:
-    save_last_error(state->errInfo);
-    return 0;
-}
-
-int
-efile_delete_file(Efile_error* errInfo,		/* Where to return error codes. */
-		  char* name)			/* Name of file to delete. */
-{
-    Efile_call_state state;
-    int ret;
-    DBG_TRACE(1, name);
-    call_state_init(&state, errInfo);
-    ret = do_delete_file(&state, name);
-    call_state_free(&state);
-    return ret;
-}
-
-static int do_delete_file(Efile_call_state* state, char* name)
-{
-    DWORD attr;
-    WCHAR *wname = (WCHAR *) name;
-
-    ensure_wpath(state, &wname);
-
-    if (DeleteFileW(wname) != FALSE) {
-	return 1;
-    }
-
-    errno = errno_map(GetLastError());
-    if (errno == EACCES) {
-        attr = GetFileAttributesW(wname);
-	if (attr != (DWORD) -1) {
-	    if (attr & FILE_ATTRIBUTE_DIRECTORY) {
-		/*
-		 * Windows NT reports removing a directory as EACCES instead
-		 * of EPERM.
-		 */
-
-		errno = EPERM;
-	    }
-	}
-    } else if (errno == ENOENT) {
-        attr = GetFileAttributesW(wname);
-	if (attr != (DWORD) -1) {
-	    if (attr & FILE_ATTRIBUTE_DIRECTORY) {
-	    	/*
-		 * Windows 95 reports removing a directory as ENOENT instead 
-		 * of EPERM.
-		 */
-
-		errno = EPERM;
-	    }
-	}
-    } else if (errno == EINVAL) {
-	/*
-	 * Windows NT reports removing a char device as EINVAL instead of
-	 * EACCES.
-	 */
-	
-	errno = EACCES;
-    }
-
-    return check_error(-1, state->errInfo);
-}
-
-/*
- *---------------------------------------------------------------------------
- *
- *      Changes the name of an existing file or directory, from src to dst.
- *	If src and dst refer to the same file or directory, does nothing
- *	and returns success.  Otherwise if dst already exists, it will be
- *	deleted and replaced by src subject to the following conditions:
- *	    If src is a directory, dst may be an empty directory.
- *	    If src is a file, dst may be a file.
- *	In any other situation where dst already exists, the rename will
- *	fail.  
- *
- *	Some possible error codes:
- *
- *	EACCES:     src or dst parent directory can't be read and/or written.
- *	EEXIST:	    dst is a non-empty directory.
- *	EINVAL:	    src is a root directory or dst is a subdirectory of src.
- *	EISDIR:	    dst is a directory, but src is not.
- *	ENOENT:	    src doesn't exist, or src or dst is "".
- *	ENOTDIR:    src is a directory, but dst is not.  
- *	EXDEV:	    src and dst are on different filesystems.
- *	
- * Side effects:
- *	The implementation of rename may allow cross-filesystem renames,
- *	but the caller should be prepared to emulate it with copy and
- *	delete if errno is EXDEV.
- *
- *---------------------------------------------------------------------------
- */
-
-int
-efile_rename(Efile_error* errInfo, char* src, char* dst)
-{
-    Efile_call_state state;
-    int ret;
-    DBG_TRACE(1, src);
-    call_state_init(&state, errInfo);
-    ret = do_rename(&state, src, dst);
-    call_state_free(&state);
-    return ret;
-}
-
-static int
-do_rename(Efile_call_state* state,
-	  char* src,			/* Original name. */
-	  char* dst)			/* New name. */
-{
-    DWORD srcAttr, dstAttr;
-    WCHAR *wsrc = (WCHAR *) src;
-    WCHAR *wdst = (WCHAR *) dst;
-
-    ensure_wpath(state, &wsrc);
-    ensure_wpath(state, &wdst);
-
-    if (MoveFileW(wsrc, wdst) != FALSE) {
-	return 1;
-    }
-
-    errno = errno_map(GetLastError());
-    srcAttr = GetFileAttributesW(wsrc);
-    dstAttr = GetFileAttributesW(wdst);
-    if (srcAttr == (DWORD) -1) {
-	srcAttr = 0;
-    }
-    if (dstAttr == (DWORD) -1) {
-	dstAttr = 0;
-    }
-
-    if (errno == EBADF) {
-	errno = EACCES;
-	return check_error(-1, state->errInfo);
-    }
-    if (errno == EACCES) {
-	decode:
-	if (srcAttr & FILE_ATTRIBUTE_DIRECTORY) {
-	    WCHAR *srcPath, *dstPath;
-	    WCHAR *srcRest, *dstRest;
-	    int size;
-
-	    srcPath = get_full_wpath_tmp(state, wsrc, &srcRest, 0);
-	    if (!srcPath) {
-		save_last_error(state->errInfo);
-		return 0;
-	    }
-
-	    dstPath = get_full_wpath_tmp(state, wdst, &dstRest, 0);
-	    if (!dstPath) {
-		save_last_error(state->errInfo);
-		return 0;
-	    }
-
-	    if (srcRest == NULL) {
-		srcRest = srcPath + wcslen(srcPath);
-	    }
-	    if (_wcsnicmp(srcPath, dstPath, srcRest - srcPath) == 0) {
-		/*
-		 * Trying to move a directory into itself.
-		 */
-
-		errno = EINVAL;
-	    }
-	    if (extract_root(srcPath)) {
-		/*
-		 * Attempt to move a root directory.  Never allowed.
-		 */
-		errno = EINVAL;
-	    }
-
-	    (void) extract_root(dstPath);
-	    if (dstPath[0] == L'\0') {
-		/*
-		 * The filename was invalid.  (Don't know why,
-		 * but play it safe.)
-		 */
-		errno = EINVAL;
-	    }
-	    if (_wcsicmp(srcPath, dstPath) != 0) {
-		/*
-		 * If src is a directory and dst filesystem != src
-		 * filesystem, errno should be EXDEV.  It is very
-		 * important to get this behavior, so that the caller
-		 * can respond to a cross filesystem rename by
-		 * simulating it with copy and delete.  The MoveFile
-		 * system call already handles the case of moving a
-		 * *file* between filesystems.
-		 */
-
-		errno = EXDEV;
-	    }
-	}
-
-	/*
-	 * Other types of access failure is that dst is a read-only
-	 * filesystem, that an open file referred to src or dest, or that
-	 * src or dest specified the current working directory on the
-	 * current filesystem.  EACCES is returned for those cases.
-	 */
-
-    } else if (errno == EEXIST) {
-	/*
-	 * Reports EEXIST any time the target already exists.  If it makes
-	 * sense, remove the old file and try renaming again.
-	 */
-
-	if (srcAttr & FILE_ATTRIBUTE_DIRECTORY) {
-	    if (dstAttr & FILE_ATTRIBUTE_DIRECTORY) {
-		/*
-		 * Overwrite empty dst directory with src directory.  The
-		 * following call will remove an empty directory.  If it
-		 * fails, it's because it wasn't empty.
-		 */
-
-		if (RemoveDirectoryW(wdst)) {
-		    /*
-		     * Now that that empty directory is gone, we can try
-		     * renaming again.  If that fails, we'll put this empty
-		     * directory back, for completeness.
-		     */
-
-		    if (MoveFileW(wsrc, wdst) != FALSE) {
-			return 1;
-		    }
-
-		    /*
-		     * Some new error has occurred.  Don't know what it
-		     * could be, but report this one.
-		     */
-
-		    errno = errno_map(GetLastError());
-		    CreateDirectoryW(wdst, NULL);
-		    SetFileAttributesW(wdst, dstAttr);
-		    if (errno == EACCES) {
-			/*
-			 * Decode the EACCES to a more meaningful error.
-			 */
-
-			goto decode;
-		    }
-		}
-	    } else {	/* (dstAttr & FILE_ATTRIBUTE_DIRECTORY) == 0 */
-		errno = ENOTDIR;
-	    }
-	} else {    /* (srcAttr & FILE_ATTRIBUTE_DIRECTORY) == 0 */
-	    if (dstAttr & FILE_ATTRIBUTE_DIRECTORY) {
-		errno = EISDIR;
-	    } else {
-		/*
-		 * Overwrite existing file by:
-		 * 
-		 * 1. Rename existing file to temp name.
-		 * 2. Rename old file to new name.
-		 * 3. If success, delete temp file.  If failure,
-		 *    put temp file back to old name.
-		 */
-
-		WCHAR *tempName;
-		int result;
-		WCHAR *rest;
-		
-		tempName = get_full_wpath_tmp(state, wdst, &rest, 14);
-		if (!tempName || !rest) {
-		    save_last_error(state->errInfo);
-		    return 0;
-		}
-
-		*rest = L'\0';
-		result = -1;
-		if (GetTempFileNameW(tempName, L"erlr", 0, tempName) != 0) {
-		    /*
-		     * Strictly speaking, need the following DeleteFile and
-		     * MoveFile to be joined as an atomic operation so no
-		     * other app comes along in the meantime and creates the
-		     * same temp file.
-		     */
-		     
-		    DeleteFileW(tempName);
-		    if (MoveFileW(wdst, tempName) != FALSE) {
-			if (MoveFileW(wsrc, wdst) != FALSE) {
-			    SetFileAttributesW(tempName, FILE_ATTRIBUTE_NORMAL);
-			    DeleteFileW(tempName);
-			    return 1;
-			} else {
-			    DeleteFileW(wdst);
-			    MoveFileW(tempName, wdst);
-			}
-		    } 
-
-		    /*
-		     * Can't backup dst file or move src file.  Return that
-		     * error.  Could happen if an open file refers to dst.
-		     */
-
-		    errno = errno_map(GetLastError());
-		    if (errno == EACCES) {
-			/*
-			 * Decode the EACCES to a more meaningful error.
-			 */
-			goto decode;
-		    }
-		}
-		return result;
-	    }
-	}
-    }
-    return check_error(-1, state->errInfo);
-}
-
-int
-efile_chdir(Efile_error* errInfo,	/* Where to return error codes. */
-	    char* name)			/* Name of directory to make current. */
-{

-    /* We don't even try to handle long paths here

-     * as current working directory is always limited to MAX_PATH

-     * even if we use UNC paths and SetCurrentDirectoryW()

-     */

-    int success = check_error(_wchdir((WCHAR *) name), errInfo);

-    if (!success && errInfo->posix_errno == EINVAL)

-	/* POSIXification of errno */

-	errInfo->posix_errno = ENOENT;
-    return success;
-}
-
-int
-efile_getdcwd(Efile_error* errInfo,		/* Where to return error codes. */
-	      int drive,			/* 0 - current, 1 - A, 2 - B etc. */
-	      char* buffer,			/* Where to return the current directory. */
-	      size_t size)			/* Size of buffer. */
-{
-    WCHAR *wbuffer = (WCHAR *) buffer;
-    size_t wbuffer_size = size / 2; 
-    DBG_TRACE(1, L"#getdcwd#");
-    if (_wgetdcwd(drive, wbuffer, wbuffer_size) == NULL) {
-	return check_error(-1, errInfo);
-    }
-    DBG_TRACE1(8, "getdcwd OS=%s", wbuffer);
-    if (wcsncmp(wbuffer, L"\\\\?\\", 4) == 0) {
-	wmemmove(wbuffer, wbuffer+4, wcslen(wbuffer+4)+1);
-    }
-    for ( ; *wbuffer; wbuffer++) 
-	if (*wbuffer == L'\\')
-	    *wbuffer = L'/';
-    DBG_TRACE1(8, "getdcwd ERLANG=%s", (WCHAR*)buffer);
-    return 1;
-}
-
-int
-efile_readdir(Efile_error* errInfo, char* name, EFILE_DIR_HANDLE* dir_handle,
-	      char* buffer, size_t *size)
-{
-    Efile_call_state state;
-    int ret;
-    DBG_TRACE(dir_handle?2:1, name);
-    call_state_init(&state, errInfo);
-    ret = do_readdir(&state, name, dir_handle, buffer, size);
-    call_state_free(&state);
-    return ret;
-}
-
-static int do_readdir(Efile_call_state* state,
-                      char* name,                   /* Name of directory to list */
-		      EFILE_DIR_HANDLE* dir_handle, /* Handle of opened directory or NULL */
-		      char* buffer,                 /* Buffer to put one filename in */
-		      size_t *size)                 /* in-out size of buffer/size of filename excluding zero
-					               termination in bytes*/
-{
-    HANDLE dir;			/* Handle to directory. */
-    WIN32_FIND_DATAW findData;	/* Data found by FindFirstFile() or FindNext(). */
-    /* Alignment is not honored, this works on x86 because of alignment fixup by processor.
-       Not perfect, but faster than alinging by hand (really) */
-    WCHAR *wbuffer = (WCHAR *) buffer;
-
-    /*
-     * First time we must setup everything.
-     */
-
-    if (*dir_handle == NULL) {
-	WCHAR *wname = (WCHAR *) name;
-	WCHAR* wildcard;
-	int length;
-	WCHAR* s;
-
-	ensure_wpath_max(state, &wname, MAX_PATH-2);
-	length = wcslen(wname);
-
-	wildcard = wpath_tmp_alloc(state, length+3);
-
-	wcscpy(wildcard, wname);
-	s = wildcard+length-1;
-	if (*s != L'/' && *s != L'\\')
-	    *++s = L'\\';
-	*++s = L'*';
-	*++s = L'\0';
-	DEBUGF(("Reading %ws\n", wildcard));
-	dir = FindFirstFileW(wildcard, &findData);
-	if (dir == INVALID_HANDLE_VALUE) {
-	    set_error(state->errInfo);
-	    return 0;
-	}
-	*dir_handle = (EFILE_DIR_HANDLE) dir;
-
-	if (!IS_DOT_OR_DOTDOT(findData.cFileName)) {
-	    wcscpy(wbuffer, findData.cFileName);
-	    *size = wcslen(wbuffer)*2;
-	    return 1;
-	}
-    }
-
-    /*
-     * Retrieve the name of the next file using the directory handle.
-     */
-
-    dir = (HANDLE) *dir_handle;
-
-    for (;;) {
-	if (FindNextFileW(dir, &findData)) {
-	    if (IS_DOT_OR_DOTDOT(findData.cFileName))
-		continue;
-	    wcscpy(wbuffer, findData.cFileName);
-	    *size = wcslen(wbuffer)*2;
-	    return 1;
-	}
-
-	if (GetLastError() == ERROR_NO_MORE_FILES) {
-	    state->errInfo->posix_errno = state->errInfo->os_errno = 0;
-	}
-	else {
-	    set_error(state->errInfo);
-	}
-	FindClose(dir);
-	return 0;
-    }
-}
-
-int
-efile_openfile(Efile_error* errInfo, char* name, int flags, int* pfd, Sint64* pSize)
-{
-    Efile_call_state state;
-    int ret;
-    DBG_TRACE1(1, "openfile(%s)", name);
-    call_state_init(&state, errInfo);
-    ret = do_openfile(&state, name, flags, pfd, pSize);
-    call_state_free(&state);
-    return ret;
-}
-
-static
-int do_openfile(Efile_call_state* state,        /* Where to return error codes. */
-	        char* name,			/* Name of directory to open. */
-	        int flags,			/* Flags to use for opening. */
-	        int* pfd,			/* Where to store the file descriptor. */
-	        Sint64* pSize)			/* Where to store the size of the file. */
-{
-    Efile_error* errInfo = state->errInfo;
-    BY_HANDLE_FILE_INFORMATION fileInfo; /* File information from a handle. */
-    HANDLE fd;			/* Handle to open file. */
-    DWORD access;		/* Access mode: GENERIC_READ, GENERIC_WRITE. */
-    DWORD crFlags;
-    DWORD flagsAndAttrs = FILE_ATTRIBUTE_NORMAL;
-    WCHAR *wname = (WCHAR *) name;
-
-    switch (flags & (EFILE_MODE_READ|EFILE_MODE_WRITE)) {
-    case EFILE_MODE_READ:
-	access = GENERIC_READ;
-	crFlags = OPEN_EXISTING;
-	break;
-    case EFILE_MODE_WRITE:
-	access = GENERIC_WRITE;
-	crFlags = CREATE_ALWAYS;
-	break;
-    case EFILE_MODE_READ_WRITE:
-	access = GENERIC_READ|GENERIC_WRITE;
-	crFlags = OPEN_ALWAYS;
-	break;
-    default:
-	errno = EINVAL;
-	check_error(-1, errInfo);
-	return 0;
-    }
-
-    if (flags & EFILE_MODE_SYNC) {
-        flagsAndAttrs = FILE_FLAG_WRITE_THROUGH;
-    }
-
-    if (flags & EFILE_MODE_APPEND) {
-	crFlags = OPEN_ALWAYS;
-    }
-    if (flags & EFILE_MODE_EXCL) {
-	crFlags = CREATE_NEW;
-    }
-    ensure_wpath(state, &wname);
-    fd = CreateFileW(wname, access,
-		    FILE_SHARE_FLAGS,
-		    NULL, crFlags, flagsAndAttrs, NULL);
-
-    /*
-     * Check for errors.
-     */
-
-    if (fd == INVALID_HANDLE_VALUE) {
-	DWORD attr;
-
-	set_error(errInfo);
-
-	/*
-	 * If the error is EACESS, the reason could be that we tried to
-	 * open a directory.  In that case, we'll change the error code
-	 * to EISDIR.
-	 */
-	if (errInfo->posix_errno && 
-	    (attr = GetFileAttributesW(wname)) != INVALID_FILE_ATTRIBUTES && 
-	    (attr & FILE_ATTRIBUTE_DIRECTORY)) {
-	    errInfo->posix_errno = EISDIR;
-	}
-	return 0;
-    }
-
-    /*
-     * Get and return the length of the open file.
-     */
-       
-    if (!GetFileInformationByHandle(fd, &fileInfo))
-	return set_error(errInfo);
-    *pfd = (int) fd;
-    if (pSize) {
-	*pSize = (Sint64)
-	    (((Uint64)fileInfo.nFileSizeHigh << 32) | 
-	     (Uint64)fileInfo.nFileSizeLow);
-    }
-    return 1;
-}
-
-int 
-efile_may_openfile(Efile_error* errInfo, char *name)
-{
-    Efile_call_state state;
-    WCHAR *wname = (WCHAR *) name;
-    DWORD attr;
-    int ret;
-
-    DBG_TRACE(1, name);
-    call_state_init(&state, errInfo);
-    ensure_wpath(&state, &wname);
-    if ((attr = GetFileAttributesW(wname)) == INVALID_FILE_ATTRIBUTES) {
-	errno = ENOENT;
-	ret = check_error(-1, errInfo);
-    }
-    else if (attr & FILE_ATTRIBUTE_DIRECTORY) {
-	errno = EISDIR;
-	ret = check_error(-1, errInfo);
-    }
-    else ret = 1;
-
-    call_state_free(&state);
-    return ret;
-}
-
-void
-efile_closefile(fd)
-int fd;				/* File descriptor for file to close. */
-{
-    DBG_TRACE(2, L"");
-    CloseHandle((HANDLE) fd);
-}
-
-FILE* efile_wfopen(const WCHAR* name, const WCHAR* mode)
-{
-    Efile_call_state state;
-    Efile_error dummy;
-    FILE* f;
-    call_state_init(&state, &dummy);
-    ensure_wpath(&state, (WCHAR**)&name);
-    f = _wfopen(name, mode);
-    call_state_free(&state);
-    return f;
-}
-
-int
-efile_fdatasync(errInfo, fd)
-Efile_error* errInfo;		/* Where to return error codes. */
-int fd;				/* File descriptor for file to sync. */
-{
-    DBG_TRACE(2, L"");
-    /* Not available in Windows, just call regular fsync */
-    return efile_fsync(errInfo, fd);
-}
-
-int
-efile_fsync(errInfo, fd)
-Efile_error* errInfo;		/* Where to return error codes. */
-int fd;				/* File descriptor for file to sync. */
-{
-    DBG_TRACE(2, L"");
-    if (!FlushFileBuffers((HANDLE) fd)) {
-	return check_error(-1, errInfo);
-    }
-    return 1;
-}
-
-int
-efile_fileinfo(Efile_error* errInfo, Efile_info* pInfo,
-	       char* orig_name, int info_for_link)
-{
-    Efile_call_state state;
-    int ret;
-    DBG_TRACE(1, L"");
-    call_state_init(&state, errInfo);
-    ret = do_fileinfo(&state, pInfo, orig_name, info_for_link);
-    call_state_free(&state);
-    return ret;
-}
-
-static int
-do_fileinfo(Efile_call_state* state, Efile_info* pInfo,
-	    char* orig_name, int info_for_link)
-{
-    Efile_error* errInfo = state->errInfo;
-    HANDLE findhandle;		/* Handle returned by FindFirstFile(). */
-    WIN32_FIND_DATAW findbuf;	/* Data return by FindFirstFile(). */
-    WCHAR* name = NULL;
-    WCHAR* win_path;
-    int name_len;
-    int drive;			/* Drive for filename (1 = A:, 2 = B: etc). */
-    WCHAR *worig_name = (WCHAR *) orig_name;
-
-    ensure_wpath(state, &worig_name);
-    /* Don't allow wildcards to be interpreted by system */
-
-
-    /*
-     * Move the name to a buffer and make sure to remove a trailing
-     * slash, because it causes FindFirstFile() to fail on Win95.
-     */
-
-    name_len = wcslen(worig_name);
-
-    name = wpath_tmp_alloc(state, name_len+1);
-    wcscpy(name, worig_name);
-    if (name_len > 2 && ISSLASH(name[name_len-1]) &&
-	name[name_len-2] != L':') {
-	name[name_len-1] = L'\0';
-    }
-
-    win_path = name;
-    if (wcsncmp(name, L"\\\\?\\", 4) == 0) {
-	win_path += 4;
-    }
-
-    if (wcspbrk(win_path, L"?*")) {
-    enoent:
-	errInfo->posix_errno = ENOENT;
-	errInfo->os_errno = ERROR_FILE_NOT_FOUND;
-        return 0;
-    }
-
-    /* Try to get disk from name.  If none, get current disk.  */
-
-    if (win_path[1] != L':') {
-	WCHAR* cwd_path = get_cwd_wpath_tmp(state);
-        drive = 0;
-	if (cwd_path[1] == L':') {
-	    drive = towlower(cwd_path[0]) - L'a' + 1;
-	}
-    } else if (*win_path && win_path[2] == L'\0') {
-	/*
-	 * X: and nothing more is an error.
-	 */
-	errInfo->posix_errno = ENOENT;
-	errInfo->os_errno = ERROR_FILE_NOT_FOUND;
-	return 0;
-    } else {
-        drive = towlower(*win_path) - L'a' + 1;
-    }
-
-    findhandle = FindFirstFileW(name, &findbuf);
-    if (findhandle == INVALID_HANDLE_VALUE) {
-	WCHAR* path = NULL;
-
-        if (!(wcspbrk(name, L"./\\") &&
-	      (path = get_full_wpath_tmp(state, name, NULL, 0)) &&
-	      /* root dir. ('C:\') or UNC root dir. ('\\server\share\') */
-	      ((wcslen(path) == 3) || is_root_unc_name(path)) &&
-	      (GetDriveTypeW(path) > 1)   ) ) {
-
-	    errInfo->posix_errno = ENOENT;
-	    errInfo->os_errno = ERROR_FILE_NOT_FOUND;
-	    return 0;
-	}
-
-        /*
-         * Root directories (such as C:\ or \\server\share\ are fabricated.
-         */
-	
-        findbuf.dwFileAttributes = FILE_ATTRIBUTE_DIRECTORY;
-        findbuf.nFileSizeHigh = 0;
-        findbuf.nFileSizeLow = 0;
-        findbuf.cFileName[0] = L'\0';
-
-	pInfo->links = 1;
-	pInfo->cTime = pInfo->accessTime = pInfo->modifyTime = 0;
-    } else {
-	SYSTEMTIME SystemTime;
-        FILETIME LocalFTime;
-
-	/*first check if we are a symlink */
-	if (!info_for_link && (findbuf.dwFileAttributes &
-			       FILE_ATTRIBUTE_REPARSE_POINT)){
-	    /*
-	     * given that we know this is a symlink,
-	     we should be able to find its target */
-	    WCHAR* target_name = (WCHAR*) do_readlink(state, (char *) name, NULL, 0);
-	    if (target_name) {
-		FindClose(findhandle);
-		return do_fileinfo(state, pInfo,
-				   (char *) target_name, info_for_link);
-	    }
-	}
-
-	/* number of links: */
-	{
-	    HANDLE handle;	/* Handle returned by CreateFile() */
-	    BY_HANDLE_FILE_INFORMATION fileInfo; /* from  CreateFile() */
-
-            /* We initialise nNumberOfLinks as GetFileInformationByHandle
-               does not always initialise this field */
-            fileInfo.nNumberOfLinks = 1;
-	    if (handle = CreateFileW(name, GENERIC_READ, FILE_SHARE_FLAGS, NULL,
-				    OPEN_EXISTING, 0, NULL)) {
-		GetFileInformationByHandle(handle, &fileInfo);
-		pInfo->links = fileInfo.nNumberOfLinks;
-		CloseHandle(handle);
-	    } else {
-		pInfo->links = 1;
-	    }	
-	}
-
-        FILETIME_TO_EPOCH(pInfo->modifyTime, findbuf.ftLastWriteTime);
-
-        if (findbuf.ftLastAccessTime.dwLowDateTime == 0 &&
-	    findbuf.ftLastAccessTime.dwHighDateTime == 0) {
-	    pInfo->accessTime = pInfo->modifyTime;
-	} else {
-	    FILETIME_TO_EPOCH(pInfo->accessTime, findbuf.ftLastAccessTime);
-	}
-
-        if (findbuf.ftCreationTime.dwLowDateTime == 0 &&
-	    findbuf.ftCreationTime.dwHighDateTime == 0) {
-	    pInfo->cTime = pInfo->modifyTime;
-	} else {
-	    FILETIME_TO_EPOCH(pInfo->cTime ,findbuf.ftCreationTime);
-	}
-        FindClose(findhandle);
-    }
-
-    pInfo->size_low = findbuf.nFileSizeLow;
-    pInfo->size_high = findbuf.nFileSizeHigh;
-	
-    if (info_for_link && (findbuf.dwFileAttributes &
-			  FILE_ATTRIBUTE_REPARSE_POINT))
-	pInfo->type = FT_SYMLINK;
-    else if (findbuf.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
-	pInfo->type = FT_DIRECTORY;
-    else
-	pInfo->type = FT_REGULAR;
-
-    if (findbuf.dwFileAttributes & FILE_ATTRIBUTE_READONLY)
-	pInfo->access = FA_READ;
-    else
-	pInfo->access = FA_READ|FA_WRITE;
-
-    pInfo->mode = dos_to_posix_mode(findbuf.dwFileAttributes, name);
-    pInfo->major_device = drive;
-    pInfo->minor_device = 0;
-    pInfo->inode = 0;
-    pInfo->uid = 0;
-    pInfo->gid = 0;
-    
-    return 1;
-}
-
-int
-efile_write_info(Efile_error* errInfo,
-		 Efile_info* pInfo,
-		 char* name)
-{
-    Efile_call_state state;
-    int ret;
-    call_state_init(&state, errInfo);
-    ret = do_write_info(&state, pInfo, name);
-    call_state_free(&state);
-    return ret;
-}
-
-static int
-do_write_info(Efile_call_state* state,
-              Efile_info* pInfo,
-	      char* name)
-{
-    Efile_error* errInfo = state->errInfo;
-    SYSTEMTIME timebuf;
-    FILETIME ModifyFileTime;
-    FILETIME AccessFileTime;
-    FILETIME CreationFileTime;
-    HANDLE fd;
-    DWORD attr;
-    DWORD tempAttr;
-    WCHAR *wname = (WCHAR *) name;
-
-    DBG_TRACE(1, name);
-
-    ensure_wpath(state, &wname);
-
-    /*
-     * Get the attributes for the file.
-     */
-
-    tempAttr = attr = GetFileAttributesW(wname);
-    if (attr == 0xffffffff) {
-	return set_error(errInfo);
-    }
-    if (pInfo->mode != -1) {
-	if (pInfo->mode & _S_IWRITE) {
-	    /* clear read only bit */
-	    attr &= ~FILE_ATTRIBUTE_READONLY;
-	} else {
-	    /* set read only bit */
-	    attr |= FILE_ATTRIBUTE_READONLY;
-	}
-    }
-
-    /*
-     * Construct all file times.
-     */
-
-    EPOCH_TO_FILETIME(ModifyFileTime,   pInfo->modifyTime);
-    EPOCH_TO_FILETIME(AccessFileTime,   pInfo->accessTime);
-    EPOCH_TO_FILETIME(CreationFileTime, pInfo->cTime);
-
-    /*
-     * If necessary, set the file times.
-     */
-
-    /*
-     * If the has read only access, we must temporarily turn on
-     * write access (this is necessary for native filesystems,
-     * but not for NFS filesystems).
-     */
-
-    if (tempAttr & FILE_ATTRIBUTE_READONLY) {
-	tempAttr &= ~FILE_ATTRIBUTE_READONLY;
-	if (!SetFileAttributesW(wname, tempAttr)) {
-	    return set_error(errInfo);
-	}
-    }
-
-    fd = CreateFileW(wname, GENERIC_READ|GENERIC_WRITE,
-	    FILE_SHARE_FLAGS,
-	    NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
-    if (fd != INVALID_HANDLE_VALUE) {
-	BOOL result = SetFileTime(fd, &CreationFileTime, &AccessFileTime, &ModifyFileTime);
-	if (!result) {
-	    return set_error(errInfo);
-	}
-	CloseHandle(fd);
-    }
-
-    /*
-     * If the file doesn't have the correct attributes, set them now.
-     * (It could have been done before setting the file times, above).
-     */
-
-    if (tempAttr != attr) {
-	if (!SetFileAttributesW(wname, attr)) {
-	    return set_error(errInfo);
-	}
-    }
-    return 1;
-}
-
-
-int
-efile_pwrite(errInfo, fd, buf, count, offset)
-Efile_error* errInfo;		/* Where to return error codes. */
-int fd;				/* File descriptor to write to. */
-char* buf;			/* Buffer to write. */
-size_t count;			/* Number of bytes to write. */
-Sint64 offset;			/* where to write it */
-{
-    int res;
-    DBG_TRACE(2, L"");
-    res = efile_seek(errInfo, fd, offset, EFILE_SEEK_SET, NULL);
-    if (res) {
-	return efile_write(errInfo, EFILE_MODE_WRITE, fd, buf, count);
-    } else {
-	return res;
-    }
-}
-
-/* position and read/write as a single atomic op */
-int
-efile_pread(errInfo, fd, offset, buf, count, pBytesRead)
-Efile_error* errInfo;		/* Where to return error codes. */
-int fd;				/* File descriptor to read from. */
-Sint64 offset;			/* Offset in bytes from BOF. */
-char* buf;			/* Buffer to read into. */
-size_t count;			/* Number of bytes to read. */
-size_t* pBytesRead;		/* Where to return number of bytes read. */
-{
-    int res;
-    DBG_TRACE(2, L"");
-    res = efile_seek(errInfo, fd, offset, EFILE_SEEK_SET, NULL);
-    if (res) {
-	return efile_read(errInfo, EFILE_MODE_READ, fd, buf, count, pBytesRead);
-    } else {
-	return res;
-    }
-}
-
-
-
-int
-efile_write(errInfo, flags, fd, buf, count)
-Efile_error* errInfo;		/* Where to return error codes. */
-int flags;			/* Flags given when file was opened. */
-int fd;				/* File descriptor to write to. */
-char* buf;			/* Buffer to write. */
-size_t count;			/* Number of bytes to write. */
-{
-    DWORD written;		/* Bytes written in last operation. */
-    OVERLAPPED overlapped;
-    OVERLAPPED* pOverlapped = NULL;
-
-    DBG_TRACE(2, L"");
-    if (flags & EFILE_MODE_APPEND) {
-	memset(&overlapped, 0, sizeof(overlapped));
-	overlapped.Offset = 0xffffffff;
-	overlapped.OffsetHigh = 0xffffffff;
-	pOverlapped = &overlapped;
-    }
-    while (count > 0) {
-	if (!WriteFile((HANDLE) fd, buf, count, &written, pOverlapped))
-	    return set_error(errInfo);
-	buf += written;
-	count -= written;
-    }
-    return 1;
-}
-
-int
-efile_writev(Efile_error* errInfo,   /* Where to return error codes */
-	     int flags,              /* Flags given when file was
-				      * opened */
-	     int fd,                 /* File descriptor to write to */
-	     SysIOVec* iov,          /* Vector of buffer structs.
-				      * The structs are unchanged 
-				      * after the call */
-	     int iovcnt)             /* Number of structs in vector */
-{
-    int cnt;                         /* Buffers so far written */
-    OVERLAPPED overlapped;
-    OVERLAPPED* pOverlapped = NULL;
-
-    DBG_TRACE(2, L"");
-    ASSERT(iovcnt >= 0);
-    
-    if (flags & EFILE_MODE_APPEND) {
-	memset(&overlapped, 0, sizeof(overlapped));
-	overlapped.Offset = 0xffffffff;
-	overlapped.OffsetHigh = 0xffffffff;
-	pOverlapped = &overlapped;
-    }
-    for (cnt = 0; cnt < iovcnt; cnt++) {
-	if (iov[cnt].iov_base && iov[cnt].iov_len > 0) {
-	    /* Non-empty buffer */
-	    int p;                   /* Position in buffer */
-	    int w = iov[cnt].iov_len;/* Bytes written in this call */
-	    for (p = 0; p < iov[cnt].iov_len; p += w) {
-		if (!WriteFile((HANDLE) fd, 
-			       iov[cnt].iov_base + p, 
-			       iov[cnt].iov_len - p, 
-			       &w, 
-			       pOverlapped))
-		    return set_error(errInfo);
-	    }
-	}
-    }	
-    return 1;
-}
-
-int
-efile_read(errInfo, flags, fd, buf, count, pBytesRead)
-Efile_error* errInfo;		/* Where to return error codes. */
-int flags;			/* Flags given when file was opened. */
-int fd;				/* File descriptor to read from. */
-char* buf;			/* Buffer to read into. */
-size_t count;			/* Number of bytes to read. */
-size_t* pBytesRead;		/* Where to return number of bytes read. */
-{
-    DWORD nbytes = 0;
-
-    DBG_TRACE(2, L"");
-    if (!ReadFile((HANDLE) fd, buf, count, &nbytes, NULL))
-	return set_error(errInfo);
-
-    *pBytesRead = nbytes;
-    return 1;
-}
-
-int
-efile_seek(errInfo, fd, offset, origin, new_location)
-Efile_error* errInfo;		/* Where to return error codes. */
-int fd;				/* File descriptor to do the seek on. */
-Sint64 offset;			/* Offset in bytes from the given origin. */
-int origin;			/* Origin of seek (SEEK_SET, SEEK_CUR,
-				 * SEEK_END).
-				 */
-Sint64* new_location;		/* Resulting new location in file. */
-{
-    LARGE_INTEGER off, new_loc;
-    
-    DBG_TRACE(2, L"");
-    switch (origin) {
-    case EFILE_SEEK_SET: origin = FILE_BEGIN; break;
-    case EFILE_SEEK_CUR: origin = FILE_CURRENT; break;
-    case EFILE_SEEK_END: origin = FILE_END; break;
-    default:
-	errno = EINVAL;
-	check_error(-1, errInfo);
-	break;
-    }
-    
-    off.QuadPart = offset;
-    if (! SetFilePointerEx((HANDLE) fd, off,
-	new_location ? &new_loc : NULL, origin)) {
-	return set_error(errInfo);
-    }
-    if (new_location) {
-	*new_location = new_loc.QuadPart;
-	DEBUGF(("efile_seek(offset=%ld, origin=%d) -> %ld\n", 
-		(long) offset, origin, (long) *new_location));
-    } else {
-	DEBUGF(("efile_seek(offset=%ld, origin=%d)\n", (long) offset, origin));
-    }
-    return 1;
-}
-
-int
-efile_truncate_file(errInfo, fd, flags)
-Efile_error* errInfo;		/* Where to return error codes. */
-int *fd;				/* File descriptor for file to truncate. */
-int flags;
-{
-    DBG_TRACE(2, L"");
-    if (!SetEndOfFile((HANDLE) (*fd)))
-	return set_error(errInfo);
-    return 1;
-}
-
-
-/*
- * is_root_unc_name - returns TRUE if the argument is a UNC name specifying
- *      a root share.  That is, if it is of the form \\server\share\.
- *      This routine will also return true if the argument is of the
- *      form \\server\share (no trailing slash) but Win32 currently
- *      does not like that form.
- *
- *      Forward slashes ('/') may be used instead of backslashes ('\').
- */
-
-static int
-is_root_unc_name(const WCHAR *path)
-{
-    /*
-     * If a root UNC name, path will start with 2 (but not 3) slashes
-     */
-
-    if ((wcslen(path) >= 5) /* minimum string is "//x/y" */
-	&& ISSLASH(path[0]) && ISSLASH(path[1]))
-    {
-        const WCHAR *p = path + 2;
-
-        /*
-         * find the slash between the server name and share name
-         */
-        while ( * ++ p )
-            if ( ISSLASH(*p) )
-                break ;
-
-        if ( *p && p[1] )
-        {
-            /*
-             * is there a further slash?
-             */
-            while ( * ++ p )
-                if ( ISSLASH(*p) )
-                    break ;
-
-            /*
-             * just final slash (or no final slash)
-             */
-            if ( !*p || !p[1])
-                return 1;
-        }
-    }
-
-    return 0 ;
-}
-
-/*
- * Extracts the root part of an absolute filename (by modifying the string
- * pointed to by the name argument).  The name can start
- * with either a driver letter (for example, C:\), or a UNC name
- * (for example, \\guinness\bjorn).
- *
- * If the name is invalid, the buffer will be modified to point to
- * an empty string.
- *
- * Returns: 1 if the name consists of just the root part, 0 if
- * 	    the name was longer.
- */
-
-static int
-extract_root(WCHAR* name)
-{
-    int len = wcslen(name);
-
-    if (iswalpha(name[0]) && name[1] == L':' && ISSLASH(name[2])) {
-	WCHAR c = name[3];
-	name[3] = L'\0';
-	return c == L'\0';
-    } else if (len < 5 || !ISSLASH(name[0]) || !ISSLASH(name[1])) {
-	goto error;
-    } else {			/* Try to find the end of the UNC name. */
-	WCHAR* p;
-	WCHAR c;
-
-        /*
-         * Find the slash between the server name and share name.
-         */
-
-	for (p = name + 2; *p; p++)
-            if (ISSLASH(*p))
-                break;
-	if (*p == L'\0')
-	    goto error;
-
-	/*
-	 * Find the slash after the share name.
-	 */
-
-	for (p++; *p; p++)
-            if (ISSLASH(*p))
-                break;
-	c = *p;
-	*p = L'\0';
-	return c == L'\0' || p[1] == L'\0';
-    }
-
- error:
-    *name = L'\0';
-    return 1;
-}
-
-static unsigned short
-dos_to_posix_mode(int attr, const WCHAR *name)
-{
-    register unsigned short uxmode;
-    unsigned dosmode;
-    register const WCHAR *p;
-
-    dosmode = attr & 0xff;
-    if ((p = name)[1] == L':')
-	p += 2;
-
-    /* check to see if this is a directory - note we must make a special
-     * check for the root, which DOS thinks is not a directory
-     */
-
-    uxmode = (unsigned short)
-	(((ISSLASH(*p) && !p[1]) || (dosmode & FILE_ATTRIBUTE_DIRECTORY) ||
-	       *p == L'\0') ? _S_IFDIR|_S_IEXEC : _S_IFREG);
-
-    /* If attribute byte does not have read-only bit, it is read-write */
-
-    uxmode |= (dosmode & FILE_ATTRIBUTE_READONLY) ?
-	_S_IREAD : (_S_IREAD|_S_IWRITE);
-
-    /* see if file appears to be executable - check extension of name */
-
-    if (p = wcsrchr(name, L'.')) {
-        if (!_wcsicmp(p, L".exe") ||
-	    !_wcsicmp(p, L".cmd") ||
-	    !_wcsicmp(p, L".bat") ||
-	    !_wcsicmp(p, L".com"))
-            uxmode |= _S_IEXEC;
-    }
-
-    /* propagate user read/write/execute bits to group/other fields */
-
-    uxmode |= (uxmode & 0700) >> 3;
-    uxmode |= (uxmode & 0700) >> 6;
-
-    return uxmode;
-}
-
-
-int
-efile_readlink(Efile_error* errInfo, char* name, char* buffer, size_t size)
-{
-    Efile_call_state state;
-    int ret;
-    DBG_TRACE(1, name);
-    call_state_init(&state, errInfo);
-    ret = !!do_readlink(&state, name, buffer, size);
-    call_state_free(&state);
-    return ret;
-}
-
-/* If buffer==0, return buffer allocated by wpath_tmp_allocate
-*/
-static char*
-do_readlink(Efile_call_state* state, char* name, char* buffer, size_t size)
-{
-    /*
-     * load dll and see if we have CreateSymbolicLink at runtime:
-     * (Vista only)
-     */
-    HINSTANCE hModule = NULL;
-    WCHAR *wname = (WCHAR *) name;
-    WCHAR *wbuffer = (WCHAR *) buffer;
-    DWORD wsize = size / sizeof(WCHAR);
-    char* ret = NULL;
-
-    if ((hModule = LoadLibrary("kernel32.dll")) != NULL) {
-	typedef DWORD (WINAPI * GETFINALPATHNAMEBYHANDLEPTR)(
-							     HANDLE hFile,
-							     LPCWSTR lpFilePath,
-							     DWORD cchFilePath,
-							     DWORD dwFlags);
-
-	GETFINALPATHNAMEBYHANDLEPTR pGetFinalPathNameByHandle =
-	    (GETFINALPATHNAMEBYHANDLEPTR)GetProcAddress(hModule, "GetFinalPathNameByHandleW");
-
-	if (pGetFinalPathNameByHandle != NULL) {
-	    DWORD fileAttributes;
-	    ensure_wpath(state, &wname);
-	    /* first check if file is a symlink; {error, einval} otherwise */
-	    fileAttributes = GetFileAttributesW(wname);
-	    if ((fileAttributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
-		DWORD success = 0;
-		HANDLE h = CreateFileW(wname, GENERIC_READ, FILE_SHARE_FLAGS, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
-		int len;
-		if(h != INVALID_HANDLE_VALUE) {
-		    if (!wbuffer) { /* dynamic allocation */
-			WCHAR dummy;
-			wsize = pGetFinalPathNameByHandle(h, &dummy, 0, 0);
-			if (wsize) {
-			    wbuffer = wpath_tmp_alloc(state, wsize);
-			}
-		    }
-		    if (wbuffer
-			&& (success = pGetFinalPathNameByHandle(h, wbuffer, wsize, 0))
-			&& success < wsize) {
-			WCHAR* wp;
-
-			/* GetFinalPathNameByHandle prepends path with "\\?\": */
-			len = wcslen(wbuffer);
-			wmemmove(wbuffer,wbuffer+4,len-3);
-			if (len - 4 >= 2 && wbuffer[1] == L':' && wbuffer[0] >= L'A' &&
-			    wbuffer[0] <= L'Z') {
-			    wbuffer[0] = wbuffer[0] + L'a' - L'A';
-			}
-			
-			for (wp=wbuffer ; *wp; wp++)
-			    if (*wp == L'\\')
-				*wp = L'/';
-		    }
-		    CloseHandle(h);
-		}
-		if (success) {
-		    ret = (char*) wbuffer;
-		} else {
-		    set_error(state->errInfo);
-		}
-	    } else {
-		errno = EINVAL;
-		save_last_error(state->errInfo);
-	    }
-	    goto done;
-	}
-    }
-    errno = ENOTSUP;
-    save_last_error(state->errInfo);
-
-done:
-    if (hModule)
-	FreeLibrary(hModule);
-    return ret;
-}
-
-
-int
-efile_altname(Efile_error* errInfo, char* orig_name, char* buffer, size_t size)
-{
-    Efile_call_state state;
-    int ret;
-    DBG_TRACE(1, orig_name);
-    call_state_init(&state, errInfo);
-    ret = do_altname(&state, orig_name, buffer, size);
-    call_state_free(&state);
-    return ret;
-}
-
-static int
-do_altname(Efile_call_state* state, char* orig_name, char* buffer, size_t size)
-{
-    WIN32_FIND_DATAW wfd;
-    HANDLE fh;
-    WCHAR* name;
-    int name_len;
-    WCHAR* full_path = NULL;
-    WCHAR *worig_name = (WCHAR *) orig_name;
-    WCHAR *wbuffer = (WCHAR *) buffer;
-    int drive;			/* Drive for filename (1 = A:, 2 = B: etc). */
-
-    /* Don't allow wildcards to be interpreted by system */
-
-    if (wcspbrk(worig_name, L"?*")) {
-    enoent:
-	state->errInfo->posix_errno = ENOENT;
-	state->errInfo->os_errno = ERROR_FILE_NOT_FOUND;
-        return 0;
-    }
-
-    /*
-     * Move the name to a buffer and make sure to remove a trailing
-     * slash, because it causes FindFirstFile() to fail on Win95.
-     */
-    ensure_wpath(state, &worig_name);
-    name_len = wcslen(worig_name);
-
-    name = wpath_tmp_alloc(state, name_len + 1);
-    wcscpy(name, worig_name);
-    if (name_len > 2 && ISSLASH(name[name_len-1]) &&
-	name[name_len-2] != L':') {
-	name[name_len-1] = L'\0';
-    }
-    
-    /* Try to get disk from name.  If none, get current disk.  */
-
-    if (name[1] != L':') {
-	WCHAR* cwd_path = get_cwd_wpath_tmp(state);
-        drive = 0;
-        if (cwd_path[1] == L':') {
-	    drive = towlower(cwd_path[0]) - L'a' + 1;
-	}
-    } else if (*name && name[2] == L'\0') {
-	/*
-	 * X: and nothing more is an error.
-	 */
-	goto enoent;
-    } else {
-        drive = towlower(*name) - L'a' + 1;
-    }
-    fh = FindFirstFileW(name,&wfd);
-    if (fh == INVALID_HANDLE_VALUE) {
-	DWORD fff_error = GetLastError();
-        if (!(wcspbrk(name, L"./\\") &&
-	      (full_path = get_full_wpath_tmp(state, name, NULL, 0)) &&
-	      /* root dir. ('C:\') or UNC root dir. ('\\server\share\') */
-	      ((wcslen(full_path) == 3) || is_root_unc_name(full_path)) &&
-	      (GetDriveTypeW(full_path) > 1)   ) ) {
-
-	    set_os_errno(state->errInfo, fff_error);
-	    return 0;
-	}
-        /*
-         * Root directories (such as C:\ or \\server\share\ are fabricated.
-         */
-	wcscpy(wbuffer,name);
-	return 1;
-    }
-	
-    wcscpy(wbuffer,wfd.cAlternateFileName);
-    if (!*wbuffer) {
-	wcscpy(wbuffer,wfd.cFileName);
-    }
-    FindClose(fh);
-    return 1;
-}
-
-
-int
-efile_link(Efile_error* errInfo, char* old, char* new)
-{
-    Efile_call_state state;
-    WCHAR *wold = (WCHAR *) old;
-    WCHAR *wnew = (WCHAR *) new;
-    int ret;
-    DBG_TRACE(1, old);
-    call_state_init(&state, errInfo);
-    ensure_wpath(&state, &wold);
-    ensure_wpath(&state, &wnew);
-    if(!CreateHardLinkW(wnew, wold, NULL)) {
-	ret = set_error(errInfo);
-    }
-    else ret =1;
-    call_state_free(&state);
-    return ret;
-}
-
-int
-efile_symlink(Efile_error* errInfo, char* old, char* new)
-{
-    Efile_call_state state;
-    int ret;
-    DBG_TRACE2(1, "symlink(%s <- %s)", old, new);
-    call_state_init(&state, errInfo);
-    ret = do_symlink(&state, old, new);
-    call_state_free(&state);
-    return ret;
-}
-
-static int
-do_symlink(Efile_call_state* state, char* old, char* new)
-{
-    /*
-     * Load dll and see if we have CreateSymbolicLink at runtime:
-     * (Vista only)
-     */
-    HINSTANCE hModule = NULL;
-    WCHAR *wold = (WCHAR *) old;
-    WCHAR *wnew = (WCHAR *) new;
-
-    DBG_TRACE(1, old);
-    if ((hModule = LoadLibrary("kernel32.dll")) != NULL) {
-	typedef BOOLEAN (WINAPI  * CREATESYMBOLICLINKFUNCPTR) (
-	     LPCWSTR lpSymlinkFileName,
-	     LPCWSTR lpTargetFileName,
-	     DWORD dwFlags);
-
-	CREATESYMBOLICLINKFUNCPTR pCreateSymbolicLink =
-	    (CREATESYMBOLICLINKFUNCPTR) GetProcAddress(hModule,
-						       "CreateSymbolicLinkW");
-	/* A for MBCS, W for UNICODE... char* above implies 'W'! */
-	if (pCreateSymbolicLink != NULL) {
-	  ensure_wpath(state, &wold);
-	  ensure_wpath(state, &wnew);
-	  {
-	    DWORD attr = GetFileAttributesW(wold);
-	    int flag = (attr != INVALID_FILE_ATTRIBUTES &&
-			attr & FILE_ATTRIBUTE_DIRECTORY) ? 1 : 0;
-	    /*  SYMBOLIC_LINK_FLAG_DIRECTORY = 1 */
-	    BOOLEAN success = pCreateSymbolicLink(wnew, wold, flag);
-	    FreeLibrary(hModule);
-
-	    if (success) {
-		return 1;
-	    } else {
-		return set_error(state->errInfo);
-	    }
-	  }
-	} else
-	    FreeLibrary(hModule);
-    }
-    errno = ENOTSUP;
-    return check_error(-1, state->errInfo);
-}
-
-int
-efile_fadvise(Efile_error* errInfo, int fd, Sint64 offset,
-	    Sint64 length, int advise)
-{
-    DBG_TRACE(2, L"");
-    /* posix_fadvise is not available on Windows, do nothing */
-    errno = ERROR_SUCCESS;
-    return check_error(0, errInfo);
-}
-
-int
-efile_fallocate(Efile_error* errInfo, int fd, Sint64 offset, Sint64 length)
-{
-    DBG_TRACE(2, L"");
-    /* No file preallocation method available in Windows. */
-    errno = errno_map(ERROR_NOT_SUPPORTED);
-    SetLastError(ERROR_NOT_SUPPORTED);
-
-    return check_error(-1, errInfo);
-}
diff --git a/erts/emulator/hipe/hipe_amd64_bifs.m4 b/erts/emulator/hipe/hipe_amd64_bifs.m4
index aff10f1528..cf4c59c9af 100644
--- a/erts/emulator/hipe/hipe_amd64_bifs.m4
+++ b/erts/emulator/hipe/hipe_amd64_bifs.m4
@@ -39,7 +39,7 @@ define(HANDLE_GOT_MBUF,`
 3:	call nbif_$1_gc_after_bif	/* `HANDLE_GOT_MBUF' */
 	jmp 2b')
 
-`#if defined(ERTS_ENABLE_LOCK_CHECK) && defined(ERTS_SMP)
+`#if defined(ERTS_ENABLE_LOCK_CHECK)
 #  define CALL_BIF(F) \
 		movq CSYM(nbif_impl_##F)@GOTPCREL(%rip), %r11; \
 		movq %r11, P_BIF_CALLEE(P); \
@@ -462,42 +462,6 @@ ASYM($1):
 	TYPE_FUNCTION(ASYM($1))
 #endif')
 
-/*
- * nogc_bif_interface_1(nbif_name, cbif_name)
- *
- * Generate native interface for a bif with implicit P
- * The bif can fail but cannot do GC.
- */
-
-define(nogc_bif_interface_1,
-`
-#ifndef HAVE_$1
-#`define' HAVE_$1
-	TEXT
-	.align	4
-	GLOBAL(ASYM($1))
-ASYM($1):
-	/* set up the parameters */
-	movq	P, %rdi
-	NBIF_ARG(%rsi,1,0)
-
-	/* make the call on the C stack */
-	SWITCH_ERLANG_TO_C
-	pushq	%rsi
-	movq	%rsp, %rsi	/* Eterm* BIF__ARGS */
-	sub	$(8), %rsp	/* stack frame 16-byte alignment */
-	CALL_BIF($2)
-	add	$(1*8 + 8), %rsp
-	SWITCH_C_TO_ERLANG
-
-	/* throw exception if failure, otherwise return */
-	TEST_GOT_EXN
-	jz	nbif_1_simple_exception
-	NBIF_RET(1)
-	SET_SIZE(ASYM($1))
-	TYPE_FUNCTION(ASYM($1))
-#endif')
-
 
 /*
  * noproc_primop_interface_0(nbif_name, cbif_name)
diff --git a/erts/emulator/hipe/hipe_arm_bifs.m4 b/erts/emulator/hipe/hipe_arm_bifs.m4
index a9097dabde..554faa2567 100644
--- a/erts/emulator/hipe/hipe_arm_bifs.m4
+++ b/erts/emulator/hipe/hipe_arm_bifs.m4
@@ -29,7 +29,7 @@ include(`hipe/hipe_arm_asm.m4')
 	.p2align 2
 	.arm
 
-`#if defined(ERTS_ENABLE_LOCK_CHECK) && defined(ERTS_SMP)
+`#if defined(ERTS_ENABLE_LOCK_CHECK)
 #  define CALL_BIF(F)	ldr r14, =nbif_impl_##F; str r14, [r0, #P_BIF_CALLEE]; bl hipe_debug_bif_wrapper
 #else
 #  define CALL_BIF(F)	bl	nbif_impl_##F
diff --git a/erts/emulator/hipe/hipe_bif0.c b/erts/emulator/hipe/hipe_bif0.c
index 94bc563fda..380031bf13 100644
--- a/erts/emulator/hipe/hipe_bif0.c
+++ b/erts/emulator/hipe/hipe_bif0.c
@@ -53,8 +53,6 @@
 #include "hipe_literals.h"
 #endif
 
-#define BeamOpCode(Op)	((Uint)BeamOp(Op))
-
 
 int term_to_Sint32(Eterm term, Sint *sp)
 {
@@ -615,7 +613,7 @@ static ErtsCodeInfo* hipe_find_emu_address(Eterm mod, Eterm name, unsigned int a
     n = code_hdr->num_functions;
     for (i = 0; i < n; ++i) {
 	ErtsCodeInfo *ci = code_hdr->functions[i];
-	ASSERT(ci->op == BeamOpCode(op_i_func_info_IaaI));
+	ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
 	if (ci->mfa.function == name && ci->mfa.arity == arity)
 	    return ci;
     }
@@ -1000,7 +998,7 @@ BIF_RETTYPE hipe_bifs_set_native_address_in_fe_2(BIF_ALIST_2)
 	BIF_ERROR(BIF_P, BADARG);
 
     fe->native_address = native_address;
-    if (erts_smp_refc_dectest(&fe->refc, 0) == 0)
+    if (erts_refc_dectest(&fe->refc, 0) == 0)
 	erts_erase_fun_entry(fe);
     BIF_RET(am_true);
 }
@@ -1048,7 +1046,7 @@ static struct {
      * they create a new stub for the mfa, which forces locking.
      * XXX: Redesign apply et al to avoid those updates.
      */
-    erts_smp_rwmtx_t lock;
+    erts_rwmtx_t lock;
 } hipe_mfa_info_table;
 
 Hash mod2mfa_tab; /* map from module atom to list of hipe_mfa_info */
@@ -1129,28 +1127,28 @@ struct hipe_ref {
 
 static inline void hipe_mfa_info_table_init_lock(void)
 {
-    erts_smp_rwmtx_init(&hipe_mfa_info_table.lock, "hipe_mfait_lock", NIL,
+    erts_rwmtx_init(&hipe_mfa_info_table.lock, "hipe_mfait_lock", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
 }
 
 static inline void hipe_mfa_info_table_rlock(void)
 {
-    erts_smp_rwmtx_rlock(&hipe_mfa_info_table.lock);
+    erts_rwmtx_rlock(&hipe_mfa_info_table.lock);
 }
 
 static inline void hipe_mfa_info_table_runlock(void)
 {
-    erts_smp_rwmtx_runlock(&hipe_mfa_info_table.lock);
+    erts_rwmtx_runlock(&hipe_mfa_info_table.lock);
 }
 
 static inline void hipe_mfa_info_table_rwlock(void)
 {
-    erts_smp_rwmtx_rwlock(&hipe_mfa_info_table.lock);
+    erts_rwmtx_rwlock(&hipe_mfa_info_table.lock);
 }
 
 static inline void hipe_mfa_info_table_rwunlock(void)
 {
-    erts_smp_rwmtx_rwunlock(&hipe_mfa_info_table.lock);
+    erts_rwmtx_rwunlock(&hipe_mfa_info_table.lock);
 }
 
 static ERTS_INLINE
@@ -1636,7 +1634,7 @@ void hipe_purge_refs(struct hipe_ref* first_ref, Eterm caller_module,
 {
     struct hipe_ref* ref = first_ref;
 
-    ERTS_SMP_LC_ASSERT(is_blocking == erts_smp_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(is_blocking == erts_thr_progress_is_blocking());
 
     while (ref) {
         struct hipe_ref* free_ref = ref;
@@ -1682,9 +1680,9 @@ void hipe_purge_sdescs(struct hipe_sdesc* first_sdesc, Eterm module,
 {
     struct hipe_sdesc* sdesc = first_sdesc;
 
-    ERTS_SMP_LC_ASSERT(is_blocking == erts_smp_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(is_blocking == erts_thr_progress_is_blocking());
 
-    ERTS_SMP_LC_ASSERT(is_blocking); /*XXX Fix safe sdesc destruction */
+    ERTS_LC_ASSERT(is_blocking); /*XXX Fix safe sdesc destruction */
 
     while (sdesc) {
         struct hipe_sdesc* free_sdesc = sdesc;
@@ -1702,7 +1700,7 @@ void hipe_purge_module(Module* modp, int is_blocking)
 {
     ASSERT(modp);
 
-    ERTS_SMP_LC_ASSERT(is_blocking == erts_smp_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(is_blocking == erts_thr_progress_is_blocking());
 
     DBG_TRACE_MFA(make_atom(modp->module), 0, 0, "hipe_purge_module");
 
@@ -1711,7 +1709,7 @@ void hipe_purge_module(Module* modp, int is_blocking)
          * Remove all hipe_ref's (external calls) from the old module instance
          */
         if (modp->old.hipe_code->first_hipe_ref) {
-            ERTS_SMP_LC_ASSERT(is_blocking);
+            ERTS_LC_ASSERT(is_blocking);
 
             hipe_purge_refs(modp->old.hipe_code->first_hipe_ref,
                             make_atom(modp->module), is_blocking);
@@ -1722,7 +1720,7 @@ void hipe_purge_module(Module* modp, int is_blocking)
          * Remove all hipe_sdesc's for the old module instance
          */
         if (modp->old.hipe_code->first_hipe_sdesc) {
-            ERTS_SMP_LC_ASSERT(is_blocking);
+            ERTS_LC_ASSERT(is_blocking);
 
             hipe_purge_sdescs(modp->old.hipe_code->first_hipe_sdesc,
                              make_atom(modp->module), is_blocking);
@@ -1773,7 +1771,7 @@ void hipe_redirect_to_module(Module* modp)
     struct hipe_mfa_info *p;
     struct hipe_ref_head* refh;
 
-    ERTS_SMP_LC_ASSERT(erts_smp_thr_progress_is_blocking());
+    ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
 
     for (p = mod2mfa_get(modp); p; p = p->next_in_mod) {
         if (p->new_address) {
diff --git a/erts/emulator/hipe/hipe_bif0.tab b/erts/emulator/hipe/hipe_bif0.tab
index 4f73770d24..0380e8c795 100644
--- a/erts/emulator/hipe/hipe_bif0.tab
+++ b/erts/emulator/hipe/hipe_bif0.tab
@@ -135,7 +135,6 @@ atom bs_utf16_size
 atom bs_put_utf16be
 atom bs_put_utf16le
 atom bs_get_utf16
-atom bs_validate_unicode
 atom bs_validate_unicode_retract
 atom emulate_fpe
 atom emasculate_binary
diff --git a/erts/emulator/hipe/hipe_bif1.c b/erts/emulator/hipe/hipe_bif1.c
index 3d3df4fd48..73d07f0ce5 100644
--- a/erts/emulator/hipe/hipe_bif1.c
+++ b/erts/emulator/hipe/hipe_bif1.c
@@ -32,11 +32,10 @@
 #include "big.h"
 #include "error.h"
 #include "beam_load.h"
+#include "erl_vm.h"
 #include "hipe_bif0.h"
 #include "hipe_bif1.h"
 
-#define BeamOpCode(Op)	((Uint)BeamOp(Op))
-
 BIF_RETTYPE hipe_bifs_call_count_on_1(BIF_ALIST_1)
 {
     ErtsCodeInfo *ci;
@@ -46,17 +45,17 @@ BIF_RETTYPE hipe_bifs_call_count_on_1(BIF_ALIST_1)
     ci = hipe_bifs_find_pc_from_mfa(BIF_ARG_1);
     if (!ci)
 	BIF_ERROR(BIF_P, BADARG);
-    ASSERT(ci->op == BeamOpCode(op_i_func_info_IaaI));
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
     pc = erts_codeinfo_to_code(ci);
-    if (pc[0] == BeamOpCode(op_hipe_trap_call))
+    if (BeamIsOpCode(pc[0], op_hipe_trap_call))
 	BIF_ERROR(BIF_P, BADARG);
-    if (pc[0] == BeamOpCode(op_hipe_call_count))
+    if (BeamIsOpCode(pc[0], op_hipe_call_count))
 	BIF_RET(NIL);
     hcc = erts_alloc(ERTS_ALC_T_HIPE_SL, sizeof(*hcc));
     hcc->count = 0;
     hcc->opcode = pc[0];
     ci->u.hcc = hcc;
-    pc[0] = BeamOpCode(op_hipe_call_count);
+    pc[0] = BeamOpCodeAddr(op_hipe_call_count);
     BIF_RET(am_true);
 }
 
@@ -70,9 +69,9 @@ BIF_RETTYPE hipe_bifs_call_count_off_1(BIF_ALIST_1)
     ci = hipe_bifs_find_pc_from_mfa(BIF_ARG_1);
     if (!ci)
 	BIF_ERROR(BIF_P, BADARG);
-    ASSERT(ci->op == BeamOpCode(op_i_func_info_IaaI));
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
     pc = erts_codeinfo_to_code(ci);
-    if (pc[0] != BeamOpCode(op_hipe_call_count))
+    if (! BeamIsOpCode(pc[0], op_hipe_call_count))
 	BIF_RET(am_false);
     hcc = ci->u.hcc;
     count = hcc->count;
@@ -91,9 +90,9 @@ BIF_RETTYPE hipe_bifs_call_count_get_1(BIF_ALIST_1)
     ci = hipe_bifs_find_pc_from_mfa(BIF_ARG_1);
     if (!ci)
 	BIF_ERROR(BIF_P, BADARG);
-    ASSERT(ci->op == BeamOpCode(op_i_func_info_IaaI));
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
     pc = erts_codeinfo_to_code(ci);
-    if (pc[0] != BeamOpCode(op_hipe_call_count))
+    if (! BeamIsOpCode(pc[0], op_hipe_call_count))
 	BIF_RET(am_false);
     hcc = ci->u.hcc;
     BIF_RET(make_small(hcc->count));
@@ -109,9 +108,9 @@ BIF_RETTYPE hipe_bifs_call_count_clear_1(BIF_ALIST_1)
     ci = hipe_bifs_find_pc_from_mfa(BIF_ARG_1);
     if (!ci)
 	BIF_ERROR(BIF_P, BADARG);
-    ASSERT(ci->op == BeamOpCode(op_i_func_info_IaaI));
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
     pc = erts_codeinfo_to_code(ci);
-    if (pc[0] != BeamOpCode(op_hipe_call_count))
+    if (! BeamIsOpCode(pc[0], op_hipe_call_count))
 	BIF_RET(am_false);
     hcc = ci->u.hcc;
     count = hcc->count;
diff --git a/erts/emulator/hipe/hipe_bif2.c b/erts/emulator/hipe/hipe_bif2.c
index e04d3d32d1..df377b2153 100644
--- a/erts/emulator/hipe/hipe_bif2.c
+++ b/erts/emulator/hipe/hipe_bif2.c
@@ -45,7 +45,7 @@ static void proc_unlock(Process* c_p, Process* rp)
 	locks &= ~ERTS_PROC_LOCK_MAIN;
     }
     if (rp && locks) {
-	erts_smp_proc_unlock(rp, locks);
+	erts_proc_unlock(rp, locks);
     }
 }
 
@@ -153,14 +153,14 @@ BIF_RETTYPE hipe_bifs_modeswitch_debug_off_0(BIF_ALIST_0)
     BIF_RET(am_true);
 }
 
-#if defined(ERTS_ENABLE_LOCK_CHECK) && defined(ERTS_SMP)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
 
 BIF_RETTYPE hipe_debug_bif_wrapper(NBIF_ALIST_1);
 
-#    define ERTS_SMP_REQ_PROC_MAIN_LOCK(P) \
+#    define ERTS_REQ_PROC_MAIN_LOCK(P) \
        if ((P)) erts_proc_lc_require_lock((P), ERTS_PROC_LOCK_MAIN,\
 					  __FILE__, __LINE__)
-#    define ERTS_SMP_UNREQ_PROC_MAIN_LOCK(P) \
+#    define ERTS_UNREQ_PROC_MAIN_LOCK(P) \
         if ((P)) erts_proc_lc_unrequire_lock((P), ERTS_PROC_LOCK_MAIN)
 
 BIF_RETTYPE hipe_debug_bif_wrapper(NBIF_ALIST_1)
@@ -168,13 +168,13 @@ BIF_RETTYPE hipe_debug_bif_wrapper(NBIF_ALIST_1)
     typedef BIF_RETTYPE nBif(NBIF_ALIST_1);
     nBif* fp = (nBif*) (BIF_P->hipe.bif_callee);
     BIF_RETTYPE res;
-    ERTS_SMP_UNREQ_PROC_MAIN_LOCK(BIF_P);
+    ERTS_UNREQ_PROC_MAIN_LOCK(BIF_P);
     res = (*fp)(NBIF_CALL_ARGS);
-    ERTS_SMP_REQ_PROC_MAIN_LOCK(BIF_P);
+    ERTS_REQ_PROC_MAIN_LOCK(BIF_P);
     return res;
 }
 
-#endif /* ERTS_ENABLE_LOCK_CHECK && ERTS_SMP */
+#endif /* ERTS_ENABLE_LOCK_CHECK*/
 
 
 BIF_RETTYPE hipe_bifs_debug_native_called_2(BIF_ALIST_2)
@@ -190,3 +190,8 @@ BIF_RETTYPE hipe_bifs_llvm_fix_pinned_regs_0(BIF_ALIST_0)
 {
     BIF_RET(am_ok);
 }
+
+BIF_RETTYPE hipe_bifs_build_stacktrace_1(BIF_ALIST_1)
+{
+    BIF_RET(build_stacktrace(BIF_P, BIF_ARG_1));
+}
diff --git a/erts/emulator/hipe/hipe_bif2.tab b/erts/emulator/hipe/hipe_bif2.tab
index bbcb577be0..c4da44606a 100644
--- a/erts/emulator/hipe/hipe_bif2.tab
+++ b/erts/emulator/hipe/hipe_bif2.tab
@@ -32,3 +32,4 @@ bif hipe_bifs:modeswitch_debug_on/0
 bif hipe_bifs:modeswitch_debug_off/0
 bif hipe_bifs:debug_native_called/2
 bif hipe_bifs:llvm_fix_pinned_regs/0
+bif hipe_bifs:build_stacktrace/1
diff --git a/erts/emulator/hipe/hipe_bif_list.m4 b/erts/emulator/hipe/hipe_bif_list.m4
index b86f2dafdc..4f0a655508 100644
--- a/erts/emulator/hipe/hipe_bif_list.m4
+++ b/erts/emulator/hipe/hipe_bif_list.m4
@@ -186,6 +186,7 @@ gc_bif_interface_1(nbif_erase_1, erase_1)
 gc_bif_interface_1(nbif_erts_internal_garbage_collect_1, erts_internal_garbage_collect_1)
 gc_nofail_primop_interface_1(nbif_gc_1, hipe_gc)
 gc_bif_interface_2(nbif_put_2, put_2)
+gc_bif_interface_2(nbif_hipe_bifs_build_stacktrace, hipe_bifs_build_stacktrace_1)
 
 /*
  * Debug BIFs that need read access to the full state.
@@ -222,7 +223,7 @@ standard_bif_interface_2(nbif_rethrow, hipe_rethrow)
 standard_bif_interface_3(nbif_find_na_or_make_stub, hipe_find_na_or_make_stub)
 standard_bif_interface_2(nbif_nonclosure_address, hipe_nonclosure_address)
 nocons_nofail_primop_interface_0(nbif_fclearerror_error, hipe_fclearerror_error)
-standard_bif_interface_2(nbif_is_divisible, hipe_is_divisible)
+noproc_primop_interface_2(nbif_is_divisible, hipe_is_divisible)
 noproc_primop_interface_1(nbif_is_unicode, hipe_is_unicode)
 
 /*
@@ -248,11 +249,6 @@ nofail_primop_interface_3(nbif_bs_get_float_2, erts_bs_get_float_2)
 standard_bif_interface_3(nbif_bs_put_utf8, hipe_bs_put_utf8)
 standard_bif_interface_3(nbif_bs_put_utf16be, hipe_bs_put_utf16be)
 standard_bif_interface_3(nbif_bs_put_utf16le, hipe_bs_put_utf16le)
-ifdef(`nogc_bif_interface_1',`
-nogc_bif_interface_1(nbif_bs_validate_unicode, hipe_bs_validate_unicode)
-',`
-standard_bif_interface_1(nbif_bs_validate_unicode, hipe_bs_validate_unicode)
-')
 
 /*
  * Bit-syntax primops without any P parameter.
@@ -267,18 +263,12 @@ noproc_primop_interface_2(nbif_bs_get_utf16, erts_bs_get_utf16)
 noproc_primop_interface_2(nbif_bs_validate_unicode_retract, hipe_bs_validate_unicode_retract)
 
 /*
- * Bit-syntax primops. The ERTS_SMP runtime system requires P,
+ * Bit-syntax primops. The runtime system requires P,
  * hence the use of nocons_nofail_primop_interface_N().
- * When ERTS_SMP is disabled, noproc_primop_interface_N()
- * should be used instead.
  */
 nocons_nofail_primop_interface_5(nbif_bs_put_small_float, hipe_bs_put_small_float)
 noproc_primop_interface_5(nbif_bs_put_bits, hipe_bs_put_bits)
-ifelse(ERTS_SMP,1,`
 nocons_nofail_primop_interface_5(nbif_bs_put_big_integer, hipe_bs_put_big_integer)
-',`
-noproc_primop_interface_5(nbif_bs_put_big_integer, hipe_bs_put_big_integer)
-')dnl
 
 nofail_primop_interface_0(nbif_check_get_msg, hipe_check_get_msg)
 
@@ -288,13 +278,8 @@ nocons_nofail_primop_interface_0(nbif_emulate_fpe, hipe_emulate_fpe)
 
 noproc_primop_interface_1(nbif_emasculate_binary, hipe_emasculate_binary)
 
-/*
- * SMP-specific stuff
- */
-ifelse(ERTS_SMP,1,`
 nocons_nofail_primop_interface_0(nbif_clear_timeout, hipe_clear_timeout)
 noproc_primop_interface_1(nbif_atomic_inc, hipe_atomic_inc)
-',)dnl
 
 /*
  * BIFs that disable GC while trapping are called via a wrapper
diff --git a/erts/emulator/hipe/hipe_instrs.tab b/erts/emulator/hipe/hipe_instrs.tab
new file mode 100644
index 0000000000..a01baebddf
--- /dev/null
+++ b/erts/emulator/hipe/hipe_instrs.tab
@@ -0,0 +1,141 @@
+// -*- c -*-
+//
+// %CopyrightBegin%
+//
+// Copyright Ericsson AB 2017. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// %CopyrightEnd%
+//
+
+
+HIPE_MODE_SWITCH(Cmd) {
+    SWAPOUT;
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    c_p->fcalls = FCALLS;
+    c_p->def_arg_reg[4] = -neg_o_reds;
+    c_p = hipe_mode_switch(c_p, $Cmd, reg);
+}
+
+hipe_trap_call := hipe_trap.call.post;
+hipe_trap_call_closure := hipe_trap.call_closure.post;
+hipe_trap_return := hipe_trap.return.post;
+hipe_trap_throw := hipe_trap.throw.post;
+hipe_trap_resume := hipe_trap.resume.post;
+
+hipe_trap.call() {
+    /*
+     * I[-5]: &&lb_i_func_info_IaaI
+     * I[-4]: Native code callee (inserted by HiPE)
+     * I[-3]: Module (tagged atom)
+     * I[-2]: Function (tagged atom)
+     * I[-1]: Arity (untagged integer)
+     * I[ 0]: &&lb_hipe_trap_call
+     * ... remainder of original BEAM code
+     */
+    ErtsCodeInfo *ci = erts_code_to_codeinfo(I);
+    ASSERT(IsOpCode(ci->op, i_func_info_IaaI));
+    c_p->hipe.u.ncallee = ci->u.ncallee;
+    ++hipe_trap_count;
+    $HIPE_MODE_SWITCH(HIPE_MODE_SWITCH_CMD_CALL | (ci->mfa.arity << 8));
+}
+
+hipe_trap.call_closure() {
+    ErtsCodeInfo *ci = erts_code_to_codeinfo(I);
+    ASSERT(IsOpCode(ci->op, i_func_info_IaaI));
+    c_p->hipe.u.ncallee = ci->u.ncallee;
+    ++hipe_trap_count;
+    $HIPE_MODE_SWITCH(HIPE_MODE_SWITCH_CMD_CALL_CLOSURE | (ci->mfa.arity << 8));
+}
+
+hipe_trap.return() {
+    $HIPE_MODE_SWITCH(HIPE_MODE_SWITCH_CMD_RETURN);
+}
+
+hipe_trap.throw() {
+    $HIPE_MODE_SWITCH(HIPE_MODE_SWITCH_CMD_THROW);
+}
+
+hipe_trap.resume() {
+    $HIPE_MODE_SWITCH(HIPE_MODE_SWITCH_CMD_RESUME);
+}
+
+hipe_trap.post() {
+#ifdef DEBUG
+    pid = c_p->common.id; /* may have switched process... */
+#endif
+    reg = erts_proc_sched_data(c_p)->x_reg_array;
+    freg = erts_proc_sched_data(c_p)->f_reg_array;
+    ERL_BITS_RELOAD_STATEP(c_p);
+    /* XXX: this abuse of def_arg_reg[] is horrid! */
+    neg_o_reds = -c_p->def_arg_reg[4];
+    FCALLS = c_p->fcalls;
+    SWAPIN;
+    ERTS_DBG_CHK_REDS(c_p, FCALLS);
+    switch( c_p->def_arg_reg[3] ) {
+    case HIPE_MODE_SWITCH_RES_RETURN:
+        ASSERT(is_value(reg[0]));
+        SET_I(c_p->cp);
+        c_p->cp = 0;
+        Goto(*I);
+    case HIPE_MODE_SWITCH_RES_CALL_EXPORTED:
+        c_p->i = c_p->hipe.u.callee_exp->addressv[erts_active_code_ix()];
+        /*fall through*/
+    case HIPE_MODE_SWITCH_RES_CALL_BEAM:
+        SET_I(c_p->i);
+        Dispatch();
+    case HIPE_MODE_SWITCH_RES_CALL_CLOSURE:
+        /* This can be used to call any function value, but currently
+           it's only used to call closures referring to unloaded
+           modules. */
+        {
+            BeamInstr *next;
+
+            next = call_fun(c_p, c_p->arity - 1, reg, THE_NON_VALUE);
+            HEAVY_SWAPIN;
+            if (next != NULL) {
+                SET_I(next);
+                Dispatchfun();
+            }
+            goto find_func_info;
+        }
+    case HIPE_MODE_SWITCH_RES_THROW:
+        c_p->cp = NULL;
+        I = handle_error(c_p, I, reg, NULL);
+        goto post_error_handling;
+    default:
+        erts_exit(ERTS_ERROR_EXIT, "hipe_mode_switch: result %u\n", c_p->def_arg_reg[3]);
+    }
+    //| -no_next;
+}
+
+hipe_call_count() {
+    /*
+     * I[-5]: &&lb_i_func_info_IaaI
+     * I[-4]: pointer to struct hipe_call_count (inserted by HiPE)
+     * I[-3]: Module (tagged atom)
+     * I[-2]: Function (tagged atom)
+     * I[-1]: Arity (untagged integer)
+     * I[ 0]: &&lb_hipe_call_count
+     * ... remainder of original BEAM code
+     */
+    ErtsCodeInfo *ci = erts_code_to_codeinfo(I);
+    struct hipe_call_count *hcc = ci->u.hcc;
+    ASSERT(IsOpCode(ci->op, i_func_info_IaaI));
+    ASSERT(hcc != NULL);
+    ASSERT(VALID_INSTR(hcc->opcode));
+    ++(hcc->count);
+    Goto(hcc->opcode);
+    //| -no_next;
+}
diff --git a/erts/emulator/hipe/hipe_mkliterals.c b/erts/emulator/hipe/hipe_mkliterals.c
index 4573980e1e..d115dfaeea 100644
--- a/erts/emulator/hipe/hipe_mkliterals.c
+++ b/erts/emulator/hipe/hipe_mkliterals.c
@@ -441,9 +441,7 @@ static const struct rts_param rts_params[] = {
     { 11, "ERL_FUN_SIZE", 1, ERL_FUN_SIZE },
 
     { 12, "P_SCHED_DATA",
-#ifdef ERTS_SMP
       1, offsetof(struct process, scheduler_data)
-#endif
     },
     { 14, "P_FP_EXCEPTION",
 #if !defined(NO_FPE_SIGNALS) || defined(HIPE)
@@ -453,22 +451,26 @@ static const struct rts_param rts_params[] = {
     /* This flag is always defined, but its value is configuration-dependent. */
     { 15, "ERTS_IS_SMP",
       1,
-#if defined(ERTS_SMP)
+      1
+    },
+    /* This flag is always defined, but its value is configuration-dependent. */
+    { 16, "ERTS_NO_FPE_SIGNALS",
+      1,
+#if defined(NO_FPE_SIGNALS)
       1
 #else
       0
 #endif
     },
     /* This flag is always defined, but its value is configuration-dependent. */
-    { 16, "ERTS_NO_FPE_SIGNALS",
+    { 17, "ERTS_USE_LITERAL_TAG",
       1,
-#if defined(NO_FPE_SIGNALS)
+#if defined(TAG_LITERAL_PTR)
       1
 #else
       0
 #endif
     },
-    /* This parameter is always defined, but its value depends on ERTS_SMP. */
     { 19, "MSG_MESSAGE",
       1, offsetof(struct erl_mesg, m[0])
     },
@@ -513,7 +515,7 @@ static const struct rts_param rts_params[] = {
 #endif
     },
     { 48, "P_BIF_CALLEE",
-#if defined(ERTS_ENABLE_LOCK_CHECK) && defined(ERTS_SMP)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
 	1, offsetof(struct process, hipe.bif_callee)
 #endif
     },
@@ -528,6 +530,9 @@ static const struct rts_param rts_params[] = {
       1, offsetof(struct process, hipe.gc_is_unsafe)
 #endif
     },
+
+    { 54, "P_MSG_LAST", 1, offsetof(struct process, msg.last) },
+    { 55, "P_MSG_SAVED_LAST", 1, offsetof(struct process, msg.saved_last) },
 };
 
 #define NR_PARAMS	ARRAY_SIZE(rts_params)
diff --git a/erts/emulator/hipe/hipe_mode_switch.c b/erts/emulator/hipe/hipe_mode_switch.c
index ba7ae1e6a8..8b497c9970 100644
--- a/erts/emulator/hipe/hipe_mode_switch.c
+++ b/erts/emulator/hipe/hipe_mode_switch.c
@@ -36,15 +36,15 @@
 #include "hipe_stack.h"
 #include "hipe_bif0.h"	/* hipe_mfa_info_table_init() */
 
-#if defined(ERTS_ENABLE_LOCK_CHECK) && defined(ERTS_SMP)
-#    define ERTS_SMP_REQ_PROC_MAIN_LOCK(P) \
+#if defined(ERTS_ENABLE_LOCK_CHECK)
+#    define ERTS_REQ_PROC_MAIN_LOCK(P) \
         if ((P)) erts_proc_lc_require_lock((P), ERTS_PROC_LOCK_MAIN,	\
 					   __FILE__, __LINE__)
-#    define ERTS_SMP_UNREQ_PROC_MAIN_LOCK(P) \
+#    define ERTS_UNREQ_PROC_MAIN_LOCK(P) \
         if ((P)) erts_proc_lc_unrequire_lock((P), ERTS_PROC_LOCK_MAIN)
 #else
-#    define ERTS_SMP_REQ_PROC_MAIN_LOCK(P)
-#    define ERTS_SMP_UNREQ_PROC_MAIN_LOCK(P)
+#    define ERTS_REQ_PROC_MAIN_LOCK(P)
+#    define ERTS_UNREQ_PROC_MAIN_LOCK(P)
 #endif
 
 
@@ -155,8 +155,6 @@ void hipe_check_pcb(Process *p, const char *file, unsigned line)
 #include "hipe_arm_glue.h"
 #endif
 
-#define BeamOpCode(Op)		((Uint)BeamOp(Op))
-
 Uint hipe_beam_pc_return[1];	/* needed in hipe_debug.c */
 Uint hipe_beam_pc_throw[1];	/* needed in hipe_debug.c */
 Uint hipe_beam_pc_resume[1];	/* needed by hipe_set_timeout() */
@@ -166,9 +164,9 @@ void hipe_mode_switch_init(void)
 {
     hipe_arch_glue_init();
 
-    hipe_beam_pc_return[0] = BeamOpCode(op_hipe_trap_return);
-    hipe_beam_pc_throw[0] = BeamOpCode(op_hipe_trap_throw);
-    hipe_beam_pc_resume[0] = BeamOpCode(op_hipe_trap_resume);
+    hipe_beam_pc_return[0] = BeamOpCodeAddr(op_hipe_trap_return);
+    hipe_beam_pc_throw[0] = BeamOpCodeAddr(op_hipe_trap_throw);
+    hipe_beam_pc_resume[0] = BeamOpCodeAddr(op_hipe_trap_resume);
 
     hipe_beam_catch_throw =
 	make_catch(beam_catches_cons(hipe_beam_pc_throw, BEAM_CATCHES_NIL));
@@ -182,8 +180,8 @@ void hipe_set_call_trap(ErtsCodeInfo* ci, void *nfun, int is_closure)
     HIPE_ASSERT(ci->op == BeamOpCode(op_i_func_info_IaaI));
     bfun[0] =
 	is_closure
-	? BeamOpCode(op_hipe_trap_call_closure)
-	: BeamOpCode(op_hipe_trap_call);
+	? BeamOpCodeAddr(op_hipe_trap_call_closure)
+	: BeamOpCodeAddr(op_hipe_trap_call);
     ci->u.ncallee = (void (*)(void)) nfun;
 }
 
@@ -394,7 +392,7 @@ Process *hipe_mode_switch(Process *p, unsigned cmd, Eterm reg[])
 	      goto do_schedule;
 	  }
 
-	  if (!(erts_smp_atomic32_read_acqb(&p->state) & ERTS_PSFLG_ACTIVE)) {
+	  if (!(erts_atomic32_read_acqb(&p->state) & ERTS_PSFLG_ACTIVE)) {
 	      for (i = 0; i < p->arity; ++i)
 		  p->arg_reg[i] = reg[i]; 	      
 	      goto do_schedule;
@@ -490,19 +488,17 @@ Process *hipe_mode_switch(Process *p, unsigned cmd, Eterm reg[])
       case HIPE_MODE_SWITCH_RES_WAIT:
       case HIPE_MODE_SWITCH_RES_WAIT_TIMEOUT: {
 	  /* same semantics, different debug trace messages */
-#ifdef ERTS_SMP
 	  /* XXX: BEAM has different entries for the locked and unlocked
 	     cases. HiPE doesn't, so we must check dynamically. */
 	  if (p->hipe_smp.have_receive_locks)
 	      p->hipe_smp.have_receive_locks = 0;
 	  else
-	      erts_smp_proc_lock(p, ERTS_PROC_LOCKS_MSG_RECEIVE);
-#endif
+	      erts_proc_lock(p, ERTS_PROC_LOCKS_MSG_RECEIVE);
 	  p->i = hipe_beam_pc_resume;
 	  p->arity = 0;
-	  erts_smp_atomic32_read_band_relb(&p->state,
+	  erts_atomic32_read_band_relb(&p->state,
 					   ~ERTS_PSFLG_ACTIVE);
-	  erts_smp_proc_unlock(p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	  erts_proc_unlock(p, ERTS_PROC_LOCKS_MSG_RECEIVE);
       do_schedule:
 	  {
 	      struct saved_calls *scb;
@@ -513,21 +509,19 @@ Process *hipe_mode_switch(Process *p, unsigned cmd, Eterm reg[])
 
               /* The process may have died while it was executing,
                  if so we return out from native code to the interpreter */
-              if (erts_smp_atomic32_read_nob(&p->state) & ERTS_PSFLG_EXITING)
+              if (erts_atomic32_read_nob(&p->state) & ERTS_PSFLG_EXITING)
                   p->i = beam_exit;
 #ifdef DEBUG
 	      ASSERT(p->debug_reds_in == reds_in);
 #endif
 	      p->flags &= ~F_HIPE_MODE;
 
-	      ERTS_SMP_UNREQ_PROC_MAIN_LOCK(p);
+	      ERTS_UNREQ_PROC_MAIN_LOCK(p);
 	      p = erts_schedule(NULL, p, reds_in - p->fcalls);
-	      ERTS_SMP_REQ_PROC_MAIN_LOCK(p);
+	      ERTS_REQ_PROC_MAIN_LOCK(p);
 	      ASSERT(!(p->flags & F_HIPE_MODE));
-#ifdef ERTS_SMP
 	      p->hipe_smp.have_receive_locks = 0;
 	      reg = p->scheduler_data->x_reg_array;
-#endif
 	  }
 	  {
 	      Eterm *argp;
@@ -651,10 +645,10 @@ void hipe_inc_nstack(Process *p)
 	p->hipe.nsp = new_nstack + (p->hipe.nsp - old_nstack);
 	p->hipe.nstack = new_nstack;
 	if (p->hipe.nstgraylim)
-	    p->hipe.nstgraylim = 
+	    p->hipe.nstgraylim =
 		new_nstack + (p->hipe.nstgraylim - old_nstack);
 	if (p->hipe.nstblacklim)
-	    p->hipe.nstblacklim = 
+	    p->hipe.nstblacklim =
 		new_nstack + (p->hipe.nstblacklim - old_nstack);
     }
 }
diff --git a/erts/emulator/hipe/hipe_native_bif.c b/erts/emulator/hipe/hipe_native_bif.c
index e1c22701d0..d6358eabf4 100644
--- a/erts/emulator/hipe/hipe_native_bif.c
+++ b/erts/emulator/hipe/hipe_native_bif.c
@@ -143,12 +143,10 @@ BIF_RETTYPE nbif_impl_hipe_set_timeout(NBIF_ALIST_1)
     else {
 	int tres = erts_set_proc_timer_term(p, timeout_value);
 	if (tres != 0) { /* Wrong time */
-#ifdef ERTS_SMP
 	    if (p->hipe_smp.have_receive_locks) {
 		p->hipe_smp.have_receive_locks = 0;
-		erts_smp_proc_unlock(p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+		erts_proc_unlock(p, ERTS_PROC_LOCKS_MSG_RECEIVE);
 	    }
-#endif
 	    BIF_ERROR(p, EXC_TIMEOUT_VALUE);
 	}
     }
@@ -256,6 +254,8 @@ void hipe_handle_exception(Process *c_p)
     /* Synthesized to avoid having to generate code for it. */
     c_p->def_arg_reg[0] = exception_tag[GET_EXC_CLASS(c_p->freason)];
 
+    c_p->msg.saved_last = 0;  /* No longer safe to use this position */
+
     hipe_find_handler(c_p);
 }
 
@@ -335,9 +335,7 @@ Binary *hipe_bs_reallocate(Binary* oldbptr, int newsize)
 }
 
 int hipe_bs_put_big_integer(
-#ifdef ERTS_SMP
     Process *p,
-#endif
     Eterm arg, Uint num_bits, byte* base, unsigned offset, unsigned flags)
 {
     byte *save_bin_buf;
@@ -486,15 +484,6 @@ static int validate_unicode(Eterm arg)
     return 1;
 }
 
-BIF_RETTYPE nbif_impl_hipe_bs_validate_unicode(NBIF_ALIST_1)
-{
-    Process *p = BIF_P;
-    Eterm arg = BIF_ARG_1;
-    if (!validate_unicode(arg))
-	BIF_ERROR(p, BADARG);
-    return NIL;
-}
-
 Uint hipe_is_unicode(Eterm arg)
 {
     return (Uint) validate_unicode(arg);
@@ -510,16 +499,12 @@ int hipe_bs_validate_unicode_retract(ErlBinMatchBuffer* mb, Eterm arg)
     return 1;
 }
 
-/* Called via standard_bif_interface_2 */
-BIF_RETTYPE nbif_impl_hipe_is_divisible(NBIF_ALIST_2)
+Uint hipe_is_divisible(Uint dividend, Uint divisor)
 {
-    /* Arguments are Eterm-sized unsigned integers */
-    Uint dividend = BIF_ARG_1;
-    Uint divisor = BIF_ARG_2;
     if (dividend % divisor) {
-	BIF_ERROR(BIF_P, BADARG);
+        return 0;
     } else {
-	return NIL;
+        return 1;
     }
 }
 
@@ -536,26 +521,22 @@ Eterm hipe_check_get_msg(Process *c_p)
     msgp = PEEK_MESSAGE(c_p);
 
     if (!msgp) {
-#ifdef ERTS_SMP
-	erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	erts_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
 	/* Make sure messages wont pass exit signals... */
 	if (ERTS_PROC_PENDING_EXIT(c_p)) {
-	    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	    erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
 	    return THE_NON_VALUE; /* Will be rescheduled for exit */
 	}
-	ERTS_SMP_MSGQ_MV_INQ2PRIVQ(c_p);
+	ERTS_MSGQ_MV_INQ2PRIVQ(c_p);
 	msgp = PEEK_MESSAGE(c_p);
 	if (msgp)
-	    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	    erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
 	else {
 	    /* XXX: BEAM doesn't need this */
 	    c_p->hipe_smp.have_receive_locks = 1;
-#endif
 	    c_p->flags &= ~F_DELAY_GC;
 	    return THE_NON_VALUE;
-#ifdef ERTS_SMP
 	}
-#endif
     }
 
     if (is_non_value(ERL_MESSAGE_TERM(msgp))
@@ -579,7 +560,6 @@ Eterm hipe_check_get_msg(Process *c_p)
 /*
  * SMP-specific stuff
  */
-#ifdef ERTS_SMP
 
 /*
  * This is like the timeout BEAM instruction.
@@ -590,14 +570,12 @@ void hipe_clear_timeout(Process *c_p)
      * A timeout has occurred.  Reset the save pointer so that the next
      * receive statement will examine the first message first.
      */
-#ifdef ERTS_SMP
     /* XXX: BEAM has different entries for the locked and unlocked
        cases. HiPE doesn't, so we must check dynamically. */
     if (c_p->hipe_smp.have_receive_locks) {
 	c_p->hipe_smp.have_receive_locks = 0;
-	erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
+	erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE);
     }
-#endif
     if (IS_TRACED_FL(c_p, F_TRACE_RECEIVE)) {
 	trace_receive(c_p, am_clock_service, am_timeout, NULL);
     }
@@ -607,7 +585,6 @@ void hipe_clear_timeout(Process *c_p)
 
 void hipe_atomic_inc(int *counter)
 {
-    erts_smp_atomic_inc_nob((erts_smp_atomic_t*)counter);
+    erts_atomic_inc_nob((erts_atomic_t*)counter);
 }
 
-#endif
diff --git a/erts/emulator/hipe/hipe_native_bif.h b/erts/emulator/hipe/hipe_native_bif.h
index 1127d4ac56..6dffec1d8d 100644
--- a/erts/emulator/hipe/hipe_native_bif.h
+++ b/erts/emulator/hipe/hipe_native_bif.h
@@ -66,10 +66,9 @@ AEXTERN(Eterm,nbif_bs_utf16_size,(Eterm));
 AEXTERN(Eterm,nbif_bs_put_utf16be,(Process*,Eterm,byte*,unsigned int));
 AEXTERN(Eterm,nbif_bs_put_utf16le,(Process*,Eterm,byte*,unsigned int));
 AEXTERN(Eterm,nbif_bs_get_utf16,(void));
-AEXTERN(Eterm,nbif_bs_validate_unicode,(Process*,Eterm));
 AEXTERN(Uint,nbif_is_unicode,(Eterm));
 AEXTERN(Eterm,nbif_bs_validate_unicode_retract,(void));
-AEXTERN(void,nbif_is_divisible,(Process*,Uint,Uint));
+AEXTERN(Uint,nbif_is_divisible,(Uint,Uint));
 
 AEXTERN(void,nbif_select_msg,(Process*));
 AEXTERN(Eterm,nbif_cmp_2,(void));
@@ -92,11 +91,10 @@ BIF_RETTYPE nbif_impl_hipe_bs_put_utf8(NBIF_ALIST_3);
 Eterm hipe_bs_utf16_size(Eterm);
 BIF_RETTYPE nbif_impl_hipe_bs_put_utf16be(NBIF_ALIST_3);
 BIF_RETTYPE nbif_impl_hipe_bs_put_utf16le(NBIF_ALIST_3);
-BIF_RETTYPE nbif_impl_hipe_bs_validate_unicode(NBIF_ALIST_1);
 Uint hipe_is_unicode(Eterm);
 struct erl_bin_match_buffer;
 int hipe_bs_validate_unicode_retract(struct erl_bin_match_buffer*, Eterm);
-BIF_RETTYPE nbif_impl_hipe_is_divisible(NBIF_ALIST_2);
+Uint hipe_is_divisible(Uint, Uint);
 
 #ifdef NO_FPE_SIGNALS
 AEXTERN(void,nbif_emulate_fpe,(Process*));
@@ -106,14 +104,13 @@ void hipe_emulate_fpe(Process*);
 AEXTERN(void,nbif_emasculate_binary,(Eterm));
 void hipe_emasculate_binary(Eterm);
 
+AEXTERN(BIF_RETTYPE,nbif_hipe_bifs_build_stacktrace,(Process*,Eterm));
+BIF_RETTYPE hipe_bifs_build_stacktrace_1(BIF_ALIST_1);
+
 /*
  * Stuff that is different in SMP and non-SMP.
  */
-#ifdef ERTS_SMP
 int hipe_bs_put_big_integer(Process*, Eterm, Uint, byte*, unsigned, unsigned);
-#else
-int hipe_bs_put_big_integer(Eterm, Uint, byte*, unsigned, unsigned);
-#endif
 
 AEXTERN(Eterm,nbif_check_get_msg,(Process*));
 Eterm hipe_check_get_msg(Process*);
@@ -124,12 +121,10 @@ BIF_RETTYPE hipe_bifs_debug_native_called_2(BIF_ALIST_2);
 /*
  * SMP-specific stuff
  */
-#ifdef ERTS_SMP
 AEXTERN(void,nbif_atomic_inc,(void));
 AEXTERN(void,nbif_clear_timeout,(Process*));
 void hipe_atomic_inc(int*);
 void hipe_clear_timeout(Process*);
-#endif
 
 #define BIF_LIST(M,F,A,B,C,I)	AEXTERN(Eterm,nbif_##C,(void));
 #include "erl_bif_list.h"
diff --git a/erts/emulator/hipe/hipe_ops.tab b/erts/emulator/hipe/hipe_ops.tab
index 96e4c0da91..19a3820a6a 100644
--- a/erts/emulator/hipe/hipe_ops.tab
+++ b/erts/emulator/hipe/hipe_ops.tab
@@ -23,4 +23,7 @@ hipe_trap_call_closure
 hipe_trap_return
 hipe_trap_throw
 hipe_trap_resume
+
+%cold
 hipe_call_count
+%hot
diff --git a/erts/emulator/hipe/hipe_ppc_bifs.m4 b/erts/emulator/hipe/hipe_ppc_bifs.m4
index 79a8bef77d..283fbbb200 100644
--- a/erts/emulator/hipe/hipe_ppc_bifs.m4
+++ b/erts/emulator/hipe/hipe_ppc_bifs.m4
@@ -25,7 +25,7 @@ include(`hipe/hipe_ppc_asm.m4')
 #`include' "config.h"
 #`include' "hipe_literals.h"
 
-`#if defined(ERTS_ENABLE_LOCK_CHECK) && defined(ERTS_SMP)
+`#if defined(ERTS_ENABLE_LOCK_CHECK)
 #  define CALL_BIF(F)	STORE_IA(CSYM(nbif_impl_##F), P_BIF_CALLEE(P), r29); bl CSYM(hipe_debug_bif_wrapper) 
 #else
 #  define CALL_BIF(F)	bl	CSYM(nbif_impl_##F)
diff --git a/erts/emulator/hipe/hipe_primops.h b/erts/emulator/hipe/hipe_primops.h
index 77f0dfe7e5..d6fd10bdff 100644
--- a/erts/emulator/hipe/hipe_primops.h
+++ b/erts/emulator/hipe/hipe_primops.h
@@ -41,10 +41,8 @@ PRIMOP_LIST(am_bnot, &nbif_bnot_1)
 
 PRIMOP_LIST(am_gc_1, &nbif_gc_1)
 PRIMOP_LIST(am_check_get_msg, &nbif_check_get_msg)
-#ifdef ERTS_SMP
 PRIMOP_LIST(am_atomic_inc, &nbif_atomic_inc)
 PRIMOP_LIST(am_clear_timeout, &nbif_clear_timeout)
-#endif
 PRIMOP_LIST(am_select_msg, &nbif_select_msg)
 PRIMOP_LIST(am_set_timeout, &nbif_set_timeout)
 PRIMOP_LIST(am_rethrow, &nbif_rethrow)
@@ -65,7 +63,6 @@ PRIMOP_LIST(am_bs_utf16_size, &nbif_bs_utf16_size)
 PRIMOP_LIST(am_bs_put_utf16be, &nbif_bs_put_utf16be)
 PRIMOP_LIST(am_bs_put_utf16le, &nbif_bs_put_utf16le)
 PRIMOP_LIST(am_bs_get_utf16, &nbif_bs_get_utf16)
-PRIMOP_LIST(am_bs_validate_unicode, &nbif_bs_validate_unicode)
 PRIMOP_LIST(am_is_unicode, &nbif_is_unicode)
 PRIMOP_LIST(am_bs_validate_unicode_retract, &nbif_bs_validate_unicode_retract)
 
@@ -86,6 +83,7 @@ PRIMOP_LIST(am_emulate_fpe, &nbif_emulate_fpe)
 #endif
 PRIMOP_LIST(am_emasculate_binary, &nbif_emasculate_binary)
 PRIMOP_LIST(am_debug_native_called, &nbif_hipe_bifs_debug_native_called)
+PRIMOP_LIST(am_build_stacktrace, &nbif_hipe_bifs_build_stacktrace)
 
 #if defined(__sparc__)
 #include "hipe_sparc_primops.h"
diff --git a/erts/emulator/hipe/hipe_process.h b/erts/emulator/hipe/hipe_process.h
index cc92bf653c..ef14c75f6c 100644
--- a/erts/emulator/hipe/hipe_process.h
+++ b/erts/emulator/hipe/hipe_process.h
@@ -49,7 +49,7 @@ struct hipe_process_state {
 #ifdef NO_FPE_SIGNALS
     double float_result;        /* to be checked for inf/NaN by hipe_emulate_fpe */ 
 #endif
-#if defined(ERTS_ENABLE_LOCK_CHECK) && defined(ERTS_SMP)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     void (*bif_callee)(void);   /* When calling BIF's via debug wrapper */
 #endif
 #ifdef DEBUG
@@ -82,7 +82,6 @@ static __inline__ void hipe_delete_process(struct hipe_process_state *p)
 	erts_free(ERTS_ALC_T_HIPE_STK, (void*)p->nstack);
 }
 
-#ifdef ERTS_SMP
 struct hipe_process_state_smp {
     int have_receive_locks;
 };
@@ -91,6 +90,5 @@ static __inline__ void hipe_init_process_smp(struct hipe_process_state_smp *p)
 {
     p->have_receive_locks = 0;
 }
-#endif
 
 #endif /* HIPE_PROCESS_H */
diff --git a/erts/emulator/hipe/hipe_signal.h b/erts/emulator/hipe/hipe_signal.h
index 5d8621135b..524def11a4 100644
--- a/erts/emulator/hipe/hipe_signal.h
+++ b/erts/emulator/hipe/hipe_signal.h
@@ -27,13 +27,9 @@
 
 #if defined(__i386__) || defined(__x86_64__)
 extern void hipe_signal_init(void);
-#else
-static __inline__ void hipe_signal_init(void) { }
-#endif
-
-#if defined(ERTS_SMP) && (defined(__i386__) || defined(__x86_64__))
 extern void hipe_thread_signal_init(void);
 #else
+static __inline__ void hipe_signal_init(void) { }
 static __inline__ void hipe_thread_signal_init(void) { }
 #endif
 
diff --git a/erts/emulator/hipe/hipe_sparc_bifs.m4 b/erts/emulator/hipe/hipe_sparc_bifs.m4
index 14330c2f1c..1b49fa57fd 100644
--- a/erts/emulator/hipe/hipe_sparc_bifs.m4
+++ b/erts/emulator/hipe/hipe_sparc_bifs.m4
@@ -28,7 +28,7 @@ include(`hipe/hipe_sparc_asm.m4')
 	.section ".text"
 	.align	4
 
-`#if defined(ERTS_ENABLE_LOCK_CHECK) && defined(ERTS_SMP)
+`#if defined(ERTS_ENABLE_LOCK_CHECK)
 #  define CALL_BIF(F)	set nbif_impl_##F, %o7; st %o7, [%o0+P_BIF_CALLEE]; call hipe_debug_bif_wrapper 
 #else
 #  define CALL_BIF(F)	call	nbif_impl_##F
diff --git a/erts/emulator/hipe/hipe_x86_bifs.m4 b/erts/emulator/hipe/hipe_x86_bifs.m4
index aecf67dc1b..9cb343d067 100644
--- a/erts/emulator/hipe/hipe_x86_bifs.m4
+++ b/erts/emulator/hipe/hipe_x86_bifs.m4
@@ -31,7 +31,7 @@ include(`hipe/hipe_x86_asm.m4')
 #define TEST_GOT_EXN	cmpl	$THE_NON_VALUE,%eax
 #endif'
 
-`#if defined(ERTS_ENABLE_LOCK_CHECK) && defined(ERTS_SMP)
+`#if defined(ERTS_ENABLE_LOCK_CHECK)
 #  define CALL_BIF(F)	movl $CSYM(nbif_impl_##F), P_BIF_CALLEE(P); call CSYM(hipe_debug_bif_wrapper) 
 #else
 #  define CALL_BIF(F)	call	CSYM(nbif_impl_##F)
diff --git a/erts/emulator/hipe/hipe_x86_signal.c b/erts/emulator/hipe/hipe_x86_signal.c
index be68d7d463..d3b6933155 100644
--- a/erts/emulator/hipe/hipe_x86_signal.c
+++ b/erts/emulator/hipe/hipe_x86_signal.c
@@ -45,10 +45,8 @@
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
-#ifdef ERTS_SMP
 #include "sys.h"
 #include "erl_alloc.h"
-#endif
 #include "hipe_signal.h"
 
 #if defined(__GLIBC__) && __GLIBC__ == 2 && (__GLIBC_MINOR__ >= 3)
@@ -259,7 +257,6 @@ static void hipe_sigaltstack(void *ss_sp)
     }
 }
 
-#ifdef ERTS_SMP
 /*
  * Set up alternate signal stack for an Erlang process scheduler thread.
  */
@@ -269,7 +266,6 @@ void hipe_thread_signal_init(void)
        We use it to suppress false leak report from valgrind */
     hipe_sigaltstack(erts_alloc_permanent_cache_aligned(ERTS_ALC_T_HIPE_LL, SIGSTKSZ));
 }
-#endif
 
 /*
  * Set up alternate signal stack for the main thread,
@@ -277,10 +273,6 @@ void hipe_thread_signal_init(void)
  */
 static void hipe_sigaltstack_init(void)
 {
-#if !defined(ERTS_SMP)
-    static unsigned long my_sigstack[SIGSTKSZ/sizeof(long)];
-    hipe_sigaltstack(my_sigstack);
-#endif
 }
 
 /*
diff --git a/erts/emulator/internal_doc/GarbageCollection.md b/erts/emulator/internal_doc/GarbageCollection.md
new file mode 100644
index 0000000000..1d9e3f4160
--- /dev/null
+++ b/erts/emulator/internal_doc/GarbageCollection.md
@@ -0,0 +1,187 @@
+# Erlang Garbage Collector
+
+Erlang manages dynamic memory with a [tracing garbage collector](https://en.wikipedia.org/wiki/Tracing_garbage_collection). More precisely a per process generational semi-space copying collector using [Cheney's](#cheney) copy collection algorithm together with a global large object space.
+
+## Overview
+
+Each Erlang process has its own stack and heap which are allocated in the same memory block and grow towards each other. When the stack and the heap [meet](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/beam_emu.c#L387), the garbage collector is triggered and memory is reclaimed. If not enough memory was reclaimed, the heap will grow.
+
+### Creating Data
+
+Terms are created on the heap by evaluating expressions. There are two major types of terms: [immediate terms](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_term.h#L88-L97) which require no heap space (small integers, atoms, pids, port ids etc) and cons or [boxed terms](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_term.h#L106-L120) (tuple, big num, binaries etc) that do require heap space. Immediate terms do not need any heap space because they are embedded into the containing structure.
+
+Let's look at an example that returns a tuple with the newly created data.
+
+```erlang
+data(Foo) ->
+   Cons = [42|Foo],
+   Literal = {text, "hello world!"},
+   {tag, Cons, Literal}.
+```
+
+In this example we first create a new cons cell with an integer and a tuple with some text. Then a tuple of size three wrapping the other values with an atom tag is created and returned.
+
+On the heap tuples require a word size for each of its elements as well as for the header. Cons cells always require two words. Adding these things together, we get seven words for the tuples and 26 words for the cons cells. The string `"hello world!"` is a list of cons cells and thus requires 24 words. The atom `tag` and the integer `42` do not require any additional heap memory since it is an *immediate*. Adding all the terms together, the heap space required in this example should be 33 words.
+
+Compiling this code to beam assembly (`erlc -S`) shows exactly what is happening.
+
+```erlang
+    ...
+    {test_heap,6,1}.
+    {put_list,{integer,42},{x,0},{x,1}}.
+    {put_tuple,3,{x,0}}.
+    {put,{atom,tag}}.
+    {put,{x,1}}.
+    {put,{literal,{text,"hello world!"}}}.
+    return.
+```
+
+Looking at the assembler code we can see three things; The heap requirement in this function turns out to be only six words, as seen by the `{test_heap,6,1}` instruction. All the allocations are combined to a single instruction. The bulk of the data `{text, "hello world!"}` is a *literal*. Literals, sometimes referred to as constants, are not allocated in the function since they are a part of the module and allocated at load time.
+
+If there is not enough space available on the heap to satisfy the `test_heap` instructions request for memory, then a garbage collection is initiated. It may happen immediately in the `test_heap` instruction, or it can be delayed until a later time depending on what state the process is in. If the garbage collection is delayed, any memory needed will be allocated in heap fragments. Heap fragments are extra memory blocks that are a part of the young heap, but are not allocated in the contigious area where terms normally reside. See [The young heap](#the-young-heap) for more details.
+
+### The collector
+
+Erlang has a copying semi-space garbage collector. This means that when doing a garbage collection, the terms are copied from one distinct area, called the *from space*, to a new clean area, called the *to space*. The collector starts by [scanning the root-set](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L1980) (stack, registers, etc).
+
+![Garbage collection: initial values](figures/gc-start.png)
+
+It follows all the pointers from the root-set to the heap and copies each term word by word to the *to space*.
+
+After the header word has been copied a [*move marker*](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.h#L45-L46) is destructively placed in it pointing to the term in the *to space*. Any other term that points to the already moved term will [see this move marker](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L1125) and copy the referring pointer instead. For example, if the have the following Erlang code:
+
+```erlang
+foo(Arg) ->
+    T = {test, Arg},
+    {wrapper, T, T, T}.
+```
+
+Only one copy of T exists on the heap and during the garbage collection only the first time T is encountered will it be copied.
+
+![Garbage collection: root set scan](figures/gc-rootset-scan.png)
+
+After [all terms](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L1089) referenced by the root-set have been copied, the collector scans the *to space* and copies all terms that these terms reference. When scanning, the collector steps through each term on the *to space* and any term still referencing the *from space* is copied over to the *to space*. Some terms contain non-term data (the payload of a on heap binary for instance). When encountered by the collector, these values are simply skipped.
+
+![Garbage collection: heap scan](figures/gc-heap-scan1.png)
+
+Every term object we can reach is copied to the *to space* and stored on top off the *scan stop* line, and then the scan stop is moved to the end of the last object.
+
+![Garbage collection: heap scan](figures/gc-heap-stop.png)
+
+When *scan stop* marker [catches up](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L1103) to the *scan start* marker, the garbage collection is done. At this point we can [deallocate](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L1206) the entire *from space* and therefore reclaim the entire young heap.
+
+## Generational Garbage Collection
+
+In addition to the collection algorithm described above, the Erlang garbage collector also provides generational garbage collection. An additional heap, called the old heap, is used where the long lived data is stored. The original heap is called the young heap, or sometimes the allocation heap.
+
+With this in mind we can look at the Erlang's garbage collection again. During the copy stage anything that should be copied to the young *to space* is instead copied to the old *to space* *if* it is [below the *high-watermark*](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L1127).
+
+![Garbage collection: heap scan](figures/gc-watermark.png)
+
+The [*high-watermark*](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_process.h#L1021) is placed where the previous garbage collection (described in [Overview](#overview)) ended and we have introduced a new area called the old heap. When doing the normal garbage collection pass, any term that is located below the high-watermark is copied to the old *to space* instead of the young.
+
+![Garbage collection: heap scan](figures/gc-watermark-2.png)
+
+In the next garbage collection, any pointers to the old heap will be ignored and not scanned. This way the garbage collector does not have to scan the long-lived terms.
+
+Generational garbage collection aims to increase performance at the expense of memory. This is achieved because only the young, smaller, heap is considered in most garbage collections.
+
+The generational [hypothesis](#ungar) predicts that most terms tend to die young, and for an immutable language such as Erlang, young terms die even faster than in other languages. So for most usage patterns the data in the new heap will die very soon after it is allocated. This is good because it limits the amount of data copied to the old heap and also because the garbage collection algorithm used is proportional to the amount of live data on the heap.
+
+One critical issue to note here is that any term on the young heap can reference terms on the old heap but *no* term on the old heap may refer to a term on the young heap. This is due to the nature of the copy algorithm. Anything referenced by an old heap term is not included in the reference tree, root-set and its followers, and hence is not copied. If it was, the data would be lost, fire and brimstone would rise to cover the earth. Fortunately, this comes naturally for Erlang because the terms are immutable and thus there can be no pointers modified on the old heap to point to the young heap.
+
+To reclaim data from the old heap, both young and old heaps are included during the collection and copied to a common *to space*. Both the *from space* of the young and old heap are then deallocated and the procedure will start over from the beginning. This type of garbage collection is called a full sweep and is triggered when the size of the area under the high-watermark is larger than the size of the free area of the old heap. It can also be triggered by doing a manual call to [erlang:garbage_collect()](http://erlang.org/doc/man/erlang.html#garbage_collect-0), or by running into the young garbage collection limit set by [spawn_opt(fun(),[{fullsweep_after, N}])](http://erlang.org/doc/man/erlang.html#spawn_opt-4) where N is the number of young garbage collections to do before forcing a garbage collection of both young and old heap.
+
+## The young heap
+
+The young heap, or the allocation heap, consists of the stack and heap as described in the Overview. However, it also includes any heap fragments that are attached to the heap. All of the heap fragments are considered to be above the high-watermark and part of the young generation. Heap fragments contain terms that either did not fit on the heap, or were created by another process and then attached to the heap. For instance if the bif binary_to_term created a term which does not fit on the current heap without doing a garbage collection, it will create a heap-fragment for the term and then schedule a garbage collection for later. Also if a message is sent to the process, the payload may be placed in a heap-fragment and that fragment is added to young heap when the message is matched in a receive clause.
+
+This procedure differs from how it worked prior to Erlang/OTP 19.0. Before 19.0, only a contiguous memory block where the young heap and stack resided was considered to be part of the young heap. Heap fragments and messages were immediately copied into the young heap before they could be inspected by the Erlang program. The behaviour introduced in 19.0 is superior in many ways - most significantly it reduces the number of necessary copy operations and the root set for garbage collection.
+
+## Sizing the heap
+
+As mentioned in the Overview the size of the heap [grows](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L247) to accommodate more data. Heaps grow in two stages, first a [variation of the Fibonacci sequence](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L199-L208) is used starting at 233 words. Then at about 1 mega words the heap only [grows in 20% increments](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L215-L227).
+
+There are two occasions when the young heap grows:
+
+* if the total size of the heap + message and heap fragments exceeds the current heap size.
+* if after a fullsweep, the total amount of live objects is greater than 75%.
+
+There are two occasions when the young heap is shrunk:
+
+* if after a young collection, the total amount of live objects is less than 25% of the heap and the young heap is "big"
+* if after a fullsweep, the total amount of live objects is less than 25% of the heap.
+
+The old heap is always one step ahead in the heap growth stages than the young heap.
+
+## Literals
+
+When garbage collecting a heap (young or old) all literals are left in place and not copied. To figure out if a term should be copied or not when doing a garbage collection the following pseudo code is used:
+
+```c
+if (erts_is_literal(ptr) || (on_old_heap(ptr) && !fullsweep)) {
+  /* literal or non fullsweep - do not copy */
+} else {
+  copy(ptr);
+}
+```
+
+The [`erts_is_literal`](https://github.com/erlang/otp/blob/OTP-19.0/erts/emulator/beam/global.h#L1452-L1465) check works differently on different architectures and operating systems.
+
+On 64 bit systems that allow mapping of unreserved virtual memory areas (most operating systems except Windows), an area of size 1 GB (by default) is mapped and then all literals are placed within that area. Then all that has to be done to determine if something is a literal or not is [two quick pointer checks](https://github.com/erlang/otp/blob/OTP-19.0/erts/emulator/beam/erl_alloc.h#L322-L324). This system relies on the fact that a memory page that has not been touched yet does not take any actual space. So even if 1 GB of virtual memory is mapped, only the memory which is actually needed for literals is allocated in ram. The size of the literal area is configurable through the +MIscs erts_alloc option.
+
+On 32 bit systems, there is not enough virtual memory space to allocate 1 GB for just literals, so instead small 256 KB sized literal regions are created on demand and a card mark bit-array of the entire 32 bit memory space is then used to determine if a term is a literal or not. Since the total memory space is only 32 bits, the card mark bit-array is only 256 words large. On a 64 bit system the same bit-array would have to be 1 tera words large, so this technique is only viable on 32 bit systems. Doing [lookups in the array](https://github.com/erlang/otp/blob/OTP-19.0/erts/emulator/beam/erl_alloc.h#L316-L319) is a little more expensive then just doing the pointer checks that can be done in 64 bit systems, but not extremely so.
+
+On 64 bit windows, on which erts_alloc cannot do unreserved virtual memory mappings, a [special tag](https://github.com/erlang/otp/blob/OTP-19.0/erts/emulator/beam/erl_term.h#L59) within the Erlang term object is used to determine if something [is a literal or not](https://github.com/erlang/otp/blob/OTP-19.0/erts/emulator/beam/erl_term.h#L248-L252). This is very cheap, however, the tag is only available on 64 bit machines, and it is possible to do a great deal of other nice optimizations with this tag in the future (like for instance a more compact list implementation) so it is not used on operating systems where it is not needed.
+
+This behaviour is different from how it worked prior to Erlang/OTP 19.0. Before 19.0 the literal check was done by checking if the pointer pointed to the young or old heap block. If it did not, then it was considered a literal. This lead to considerable overhead and strange memory usage scenarios, so it was removed in 19.0.
+
+## Binary heap
+
+The binary heap works as a large object space for binary terms that are greater than 64 bytes (from now on called off-heap binaries). The binary heap is [reference counted](https://en.wikipedia.org/wiki/Reference_counting) and a pointer to the off-heap binary is stored on the process heap. To keep track of when to decrement the reference counter of the off-heap binary, a linked list (the MSO - mark and sweep object list) containing funs and externals as well as off-heap binaries is woven through the heap. After a garbage collection is done, the [MSO list is swept](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L2299) and any off-heap binary that does not have a [move marker](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L2325) written into the header words has its reference [decremented and is potentially freed](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L2344-L2367).
+
+All items in the MSO list are ordered by the time they were added to the process heap, so when doing a minor garbage collection, the MSO sweeper only has to sweep until it [encounters an off-heap binary that is on the old heap](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_gc.c#L2369).
+
+### Virtual Binary heap
+
+Each process has a virtual binary heap associated with it that has the size of all the current off-heap binaries that the process has references to. The virtual binary heap also has a limit and grows and shrinks depending on how off-heap binaries are used by the process. The same growth and shrink mechanisms are used for the binary heap and for the term heap, so first a Fibonacci like series and then 20% growth.
+
+The virtual binary heap exists in order to [trigger](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/beam_emu.c#L364) garbage collections earlier when potentially there is a very large amount of off-heap binary data that could be reclaimed. This approach does not catch all problems with binary memory not being released soon enough, but it does catch a lot of them.
+
+## Messages
+
+Messages can become a part of the process heap at different times. This depends on how the process is configured.
+We can configure the behaviour of each process using `process_flag(message_queue_data, off_heap | on_heap)` or we can set a default for all processes at start using the option `+hmqd`.
+
+What do these different configurations do and when should we use them?
+Let's start by going through what happens when one Erlang process sends a message to another.
+The sending process needs to do a couple of things:
+
+1. calculate [how large](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_message.c#L1031) the message to be sent is
+2. [allocate enough space](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_message.c#L1033) to fit the entire message
+3. [copy](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_message.c#L1040) the message payload
+4. allocate a message container with some meta data
+5. [insert](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_message.c#L502) the message container in the receiver process' [message queue](https://github.com/erlang/otp/blob/OTP-18.0/erts/emulator/beam/erl_process.h#L1042)
+
+The process flag `message_queue_data`, of the receiver process, controls the message allocating strategy of the sender process in step 2 and also how the message data is treated by the garbage collector.
+
+The procedure above is different from how it worked prior to 19.0. Before 19.0 there was no configuration option, the behaviour was always very similar to how the `on_heap` option is in 19.0.
+
+### Message allocating strategies
+
+If set to `on_heap`, the sending process will first attempt to allocate the space for the message directly on the young heap block of the receiving process.
+This is not always possible as it requires taking the *main lock* of the receiving process. The main lock is also held when the process is executing. The possibility for a lock conflict is thus likely in an intensely collaborating system.
+If the sending process cannot acquire the main lock, a heap fragment is instead created for the message and the message payload is copied onto that.
+With the `off_heap` option the sender process always creates heap fragments for messages sent to that process.
+
+There are a bunch of different tradeoffs that come into play when trying to figure out which of the strategies you want to use.
+
+Using `off_heap` may seem like a nice way to get a more scalable system as you get very little contention on the main locks, however, allocating a heap fragment is more expensive than allocating on the heap of the receiving process. So if it is very unlikely that contention will occur, it is more efficient to try to allocate the message directly on the receiving process' heap.
+
+Using `on_heap` will force all messages to be part of on the young heap which will increase the amount of data that the garbage collector has to move. So if a garbage collection is triggered while processing a large amount of messages, they will be copied to the young heap. This in turn will lead to that the messages will quickly be promoted to the old heap and thus increase its size. This may be good or bad depending on exactly what the process does. A large old heap means that the young heap will also be larger, which in turn means that less garbage collections will be triggered while processing the message queue. This will temporarly increase the throughput of the process at the cost of more memory usage. However, if after all the messages have been consumed the process enters a state where a lot less messages are being received. Then it may be a long time before the next fullsweep garbage collection happens and the messages that are on the old heap will be there until that happens. So while `on_heap` is potentially faster than the other modes, it uses more memory for a longer time. This mode is the legacy mode which is almost how the message queue was handled before Erlang/OTP 19.0.
+
+Which one of these strategies is best depends a lot on what the process is doing and how it interacts with other processes. So, as always, profile the application and see how it behaves with the different options.
+
+   <a name="cheney">[1]</a>: C. J. Cheney. A nonrecursive list compacting algorithm. Commun. ACM, 13(11):677–678, Nov. 1970.
+
+   <a name="ungar">[2]</a>: D. Ungar. Generation scavenging: A non-disruptive high performance storage reclamation algorithm. SIGSOFT Softw. Eng. Notes, 9(3):157–167, Apr. 1984.
diff --git a/erts/emulator/internal_doc/beam_makeops.md b/erts/emulator/internal_doc/beam_makeops.md
new file mode 100644
index 0000000000..1da8d2ab05
--- /dev/null
+++ b/erts/emulator/internal_doc/beam_makeops.md
@@ -0,0 +1,1846 @@
+The beam\_makeops script
+=======================
+
+This document describes the **beam\_makeops** script.
+
+Introduction
+------------
+
+The **beam\_makeops** Perl script is used at build-time by both the
+compiler and runtime system.  Given a number of input files (all with
+the extension `.tab`), it will generate source files used by the
+Erlang compiler and by the runtime system to load and execute BEAM
+instructions.
+
+Essentially those `.tab` files define:
+
+* External generic BEAM instructions.  They are the instructions that
+are known to both the compiler and the runtime system.  Generic
+instructions are stable between releases.  New generic instructions
+with high numbers than previous instructions can be added in major
+releases.  The OTP 20 release has 159 external generic instructions.
+
+* Internal generic instructions.  They are known only to the runtime
+system and can be changed at any time without compatibility issues.
+They are created by transformation rules (described next).
+
+* Rules for transforming one or more generic instructions to other
+generic instructions.  The transformation rules allow combining,
+splitting, and removal of instructions, as well as shuffling operands.
+Because of the transformation rules, the runtime can have many
+internal generic instructions that are only known to runtime system.
+
+* Specific BEAM instructions.  The specific instructions are the
+instructions that are actually executed by the runtime system.  They
+can be changed at any time without causing compatibility issues.
+The loader translates generic instructions to specific instructions.
+In general, for each generic instruction, there exists a family of
+specific instructions.  The OTP 20 release has 389 specific
+instructions.
+
+* The implementation of specific instructions.
+
+Generic instructions have typed operands. Here are a few examples of
+operands for `move/2`:
+
+    {move,{atom,id},{x,5}}.
+    {move,{x,3},{x,0}}.
+    {move,{x,2},{y,1}}.
+
+When those instructions are loaded, the loader rewrites them
+to specific instructions:
+
+    move_cx id 5
+    move_xx 3 0
+    move_xy 2 1
+
+Corresponding to each generic instruction, there is a family of
+specific instructions.  The types that an instance of a specific
+instruction can handle are encoded in the instruction names.  For
+example, `move_xy` takes an X register number as the first operand and
+a Y register number as the second operand.  `move_cx` takes a tagged
+Erlang term as the first operand and an X register number as the
+second operand.
+
+An example: the move instruction
+--------------------------------
+
+Using the `move` instruction as an example, we will give a quick
+tour to show the main features of **beam\_makeops**.
+
+In the `compiler` application, in the file `genop.tab`, there is the
+following line:
+
+    64: move/2
+
+This is a definition of an external generic BEAM instruction. Most
+importantly it specifices that the opcode is 64.  It also defines that
+it has two operands.  The BEAM assembler will use the opcode when
+creating `.beam` files.  The compiler does not really need the arity,
+but it will use it as an internal sanity check when assembling the
+BEAM code.
+
+Let's have a look at `ops.tab` in `erts/emulator/beam`, where the
+specific `move` instructions are defined.  Here are a few of them:
+
+    move x x
+    move x y
+    move c x
+
+Each specific instructions is defined by following the name of the
+instruction with the types for each operand.  An operand type is a
+single letter.  For example, `x` means an X register, `y`
+means a Y register, and `c` is a "constant" (a tagged term such as
+an integer, an atom, or a literal).
+
+Now let's look at the implementation of the `move` instruction.  There
+are multiple files containing implementations of instructions in the
+`erts/emulator/beam` directory.  The `move` instruction is defined in
+`instrs.tab`.  It looks like this:
+
+    move(Src, Dst) {
+        $Dst = $Src;
+    }
+
+The implementation for an instruction largely follows the C syntax,
+except that the variables in the function head don't have any types.
+The `$` before an identifier denotes a macro expansion.  Thus,
+`$Src` will expand to the code to pick up the source operand for
+the instruction and `$Dst` to the code for the destination register.
+
+We will look at the code for each specific instruction in turn.  To
+make the code easier to understand, let's first look at the memory
+layout for the instruction `{move,{atom,id},{x,5}}`:
+
+         +--------------------+--------------------+
+    I -> |                 40 |       &&lb_move_cx |
+         +--------------------+--------------------+
+         |                        Tagged atom 'id' |
+         +--------------------+--------------------+
+
+This example and all other examples in the document assumes a 64-bit
+archictecture, and furthermore that pointers to C code fit in 32 bits.
+
+`I` in the BEAM virtual machine is the instruction pointer.  When BEAM
+executes an instruction, `I` points to the first word of the
+instruction.
+
+`&&lb_move_cx` is the address to C code that implements `move_cx`.  It
+is stored in the lower 32 bits of the word.  In the upper 32 bits is
+the byte offset to the X register; the register number 5 has been
+multiplied by the word size size 8.
+
+In the next word the tagged atom `id` is stored.
+
+With that background, we can look at the generated code for `move_cx`
+in `beam_hot.h`:
+
+    OpCase(move_cx):
+    {
+      BeamInstr next_pf = BeamCodeAddr(I[2]);
+      xb(BeamExtraData(I[0])) = I[1];
+      I += 2;
+      ASSERT(VALID_INSTR(next_pf));
+      GotoPF(next_pf);
+    }
+
+We will go through each line in turn.
+
+* `OpCase(move_cx):` defines a label for the instruction.  The
+`OpCase()` macro is defined in `beam_emu.c`.  It will expand this line
+to `lb_move_cx:`.
+
+* `BeamInstr next_pf = BeamCodeAddr(I[2]);` fetches the pointer to
+code for the next instruction to be executed.  The `BeamCodeAddr()`
+macro extracts the pointer from the lower 32 bits of the instruction
+word.
+
+* `xb(BeamExtraData(I[0])) = I[1];` is the expansion of `$Dst = $Src`.
+`BeamExtraData()` is a macro that will extract the upper 32 bits from
+the instruction word.  In this example, it will return 40 which is the
+byte offset for X register 5.  The `xb()` macro will cast a byte
+pointer to an `Eterm` pointer and dereference it.  The `I[1]` on
+the right side of the `=` fetches an Erlang term (the atom `id` in
+this case).
+
+* `I += 2` advances the instruction pointer to the next
+instruction.
+
+* In a debug-compiled emulator, `ASSERT(VALID_INSTR(next_pf));` makes
+sure that `next_pf` is a valid instruction (that is, that it points
+within the `process_main()` function in `beam_emu.c`).
+
+* `GotoPF(next_pf);` transfers control to the next instruction.
+
+Now let's look at the implementation of `move_xx`:
+
+    OpCase(move_xx):
+    {
+      Eterm tmp_packed1 = BeamExtraData(I[0]);
+      BeamInstr next_pf = BeamCodeAddr(I[1]);
+      xb((tmp_packed1>>BEAM_TIGHT_SHIFT)) = xb(tmp_packed1&BEAM_TIGHT_MASK);
+      I += 1;
+      ASSERT(VALID_INSTR(next_pf));
+      GotoPF(next_pf);
+    }
+
+We will go through the lines that are new or have changed compared to
+`move_cx`.
+
+* `Eterm tmp_packed1 = BeamExtraData(I[0]);` picks up both X register
+numbers packed into the upper 32 bits of the instruction word.
+
+* `BeamInstr next_pf = BeamCodeAddr(I[1]);` pre-fetches the address of
+the next instruction. Note that because both X registers operands fits
+into the instruction word, the next instruction is in the very next
+word.
+
+* `xb((tmp_packed1>>BEAM_TIGHT_SHIFT)) = xb(tmp_packed1&BEAM_TIGHT_MASK);`
+copies the source to the destination.  (For a 64-bit architecture,
+`BEAM_TIGHT_SHIFT` is 16 and `BEAM_TIGHT_MASK` is `0xFFFF`.)
+
+* `I += 1;` advances the instruction pointer to the next instruction.
+
+`move_xy` is almost identical to `move_xx`.  The only difference is
+the use of the `yb()` macro instead of `xb()` to reference the
+destination register:
+
+    OpCase(move_xy):
+    {
+      Eterm tmp_packed1 = BeamExtraData(I[0]);
+      BeamInstr next_pf = BeamCodeAddr(I[1]);
+      yb((tmp_packed1>>BEAM_TIGHT_SHIFT)) = xb(tmp_packed1&BEAM_TIGHT_MASK);
+      I += 1;
+      ASSERT(VALID_INSTR(next_pf));
+      GotoPF(next_pf);
+    }
+
+### Transformation rules ###
+
+Next let's look at how we can do some optimizations using transformation
+rules.  For simple instructions such as `move/2`, the instruction dispatch
+overhead can be substantial.  A simple optimization is to combine common
+instructions sequences to a single instruction.  One such common sequence
+is multiple `move` instructions moving X registers to Y registers.
+
+Using the following rule we can combine two `move` instructions
+to a `move2` instruction:
+
+    move X1=x Y1=y | move X2=x Y2=y => move2 X1 Y1 X2 Y2
+
+The left side of the arrow (`=>`) is a pattern.  If the pattern
+matches, the matching instructions will be replaced by the
+instructions on the right side.  Variables in a pattern must start
+with an uppercase letter just as in Erlang.  A pattern variable may be
+followed `=` and one or more type letters to constrain the match to
+one of those types.  The variables that are bound on the left side can
+be used on the right side.
+
+We will also need to define a specific instruction and an implementation:
+
+    # In ops.tab
+    move2 x y x y
+
+    // In instrs.tab
+    move2(S1, D1, S2, D2) {
+        Eterm V1, V2;
+        V1 = $S1;
+        V2 = $S2;
+        $D1 = V1;
+        $D2 = V2;
+    }
+
+When the loader has found a match and replaced the matched instructions,
+it will match the new instructions against the transformation rules.
+Because of that, we can define the rule for a `move3/6` instruction
+as follows:
+
+    move2 X1=x Y1=y X2=x Y2=y | move X3=x Y3=y => \
+          move3 X1 Y1 X2 Y2 X3 Y3
+
+(A `\` before a newline can be used to break a long line for readability.)
+
+It would also be possible to define it like this:
+
+    move X1=x Y1=y | move X2=x Y2=y | move X3=x Y3=y => \
+         move3 X1 Y1 X2 Y2 X3 Y3
+
+but in that case it must be defined before the rule for `move2/4`
+because the first matching rule will be applied.
+
+One must be careful not to create infinite loops.  For example, if we
+for some reason would want to reverse the operand order for the `move`
+instruction, we must not do like this:
+
+    move Src Dst => move Dst Src
+
+The loader would swap the operands forever.  To avoid the loop, we must
+rename the instruction.  For example:
+
+    move Src Dst => assign Dst Src
+
+This concludes the quick tour of the features of **beam\_makeops**.
+
+Short overview of instruction loading
+-------------------------------------
+
+To give some background to the rest of this document, here follows a
+quick overview of how instructions are loaded.
+
+* The loader reads and decodes one instruction at a time from the BEAM
+code and creates a generic instruction.  Many transformation rules
+must look at multiple instructions, so the loader will
+keep multiple generic instructions in a linked list.
+
+* The loader tries to apply transformation rules against the
+generic instructions in the linked list.  If a rule matches, the
+matched instructions will be removed and replaced with new
+generic instructions constructed from the right side of the
+transformation.
+
+* If a transformation rule matched, the loader applies the
+transformation rules again.
+
+* If no transformation rule match, the loader will begin rewriting
+the first of generic instructions to a specific instruction.
+
+* First the loader will search for a specific operation where the
+types for all operands match the type for the generic instruction.
+The first matching instruction will be selected.  **beam\_makeops**
+has ordered the specific instructions so that instructions with more
+specific operands comes before instructions with less specific
+operands.  For example, `move_nx` is more specific than `move_cx`.  If
+the first operand is `[]` (NIL), `move_nx` will be selected.
+
+* Given the opcode for the selected specific instruction, the loader
+looks up the pointer to the C code for the instruction and stores
+in the code area for the module being loaded.
+
+* The loader translates each operand to a machine word and stores it
+in the code area.  The operand type for the selected specific
+instruction guides the translation.  For example, if the type is `e`,
+the value of the operand is an index into an arry of external
+functions and will be translated to a pointer to the export entry for
+the function to call.  If the type is `x`, the number of the X
+register will be multiplied by the word size to produce a byte offset.
+
+* The loader runs the packing engine to pack multiple operands into a
+single word.  The packing engine is controlled by a small program,
+which is a string where each character is an instruction.  For
+example, the code to pack the operands for `move_xy` is `"22#"` (on a
+64-bit machine).  That program will pack the byte offsets for both
+registers into the same word as the pointer to C code.
+
+Running beam_makeops
+--------------------
+
+**beam\_makeops** is found in `$ERL_TOP/erts/emulator/utils`.  Options
+start with a hyphen (`-`).  The options are followed by the name of
+the input files.  By convention, all input files have the extension
+`.tab`, but is not enforced by **beam\_makeops**.
+
+### The -outdir option ###
+
+The option `-outdir Directory` specifies the output directory for
+the generated files.  Default is the current working directory.
+
+### Running beam_makeops for the compiler ###
+
+Give the option `-compiler` to produce output files for the compiler.
+The following files will be written to the output directory:
+
+* `beam_opcodes.erl` - Used primarily by `beam_asm` and `beam_diasm`.
+
+* `beam_opcode.hrl` - Used by `beam_asm`.  It contains tag definitions
+used for encoding instruction operands.
+
+The input file should only contain the definition of BEAM_FORMAT_NUMBER
+and external generic instructions.  (Everything else would be ignored.)
+
+### Running beam_makeops for the emulator ###
+
+Give the option `-emulator` to produce output files for the emulator.
+The following output files will be generated in the output directory.
+
+* `beam_hot.h`, `beam_warm.h`, `beam_cold.`h - Implementation of
+instructions.  Included inside the `process_main()` function in
+`beam_emu.c`.
+
+* `beam_opcodes.c` - Defines static data used by the loader
+(`beam_load.c`).  Data about generic instructions, specific
+instructions (including how to pack their operands), and
+transformation rules are all part of this file.
+
+* `beam_opcodes.h` - Miscellanous preprocessor definitions, mainly
+used by `beam_load.c` but also by `beam_{hot,warm,cold}.h`.
+
+* `beam_pred_funcs.h` - Included by `beam_load.c`.  Contains defines
+needed to call guard constraints in transformation rules.
+
+* `beam_tr_funcs.h` - Included by `beam_load.c`.  Contains defines
+needed to call a C function to the right of a transformation rule.
+
+The following options can be given:
+
+* `wordsize 32|64` - Defines the word size.  Default is 32.
+
+* `code-model Model` - The code model as given to `-mcmodel` option
+for GCC.  Default is `unknown`.  If the code model is `small` (and
+the word size is 64 bits), **beam\_makeops** will pack operands
+into the upper 32 bits of the instruction word.
+
+* `DSymbol=0|1` - Defines the value for a symbol.  The symbol can be
+used in `%if` and `%unless` directives.
+
+Syntax of .tab files
+--------------------
+
+### Comments ###
+
+Any line starting with `#` is a comment and is ignored.
+
+A line with `//` is also a comment.  It is recommended to only
+use this style of comments in files that define implementations of
+instructions.
+
+A long line can be broken into shorter lines by a placing a`\` before
+the newline.
+
+### Variable definitions ###
+
+A variable definition binds a variable to a Perl variable.  It is only
+meaningful to add a new definition if **beam\_makeops** is updated
+at the same time to use the variable.  A variable definition looks this:
+
+*name*=*value*[;]
+
+where *name* is the name of a Perl variable in **beam\_makeops**,
+and *value* is the value to be given to the variable.  The line
+can optionally end with a `;` (to avoid messing up the
+C indentation mode in Emacs).
+
+Here follows a description of the variables that are defined.
+
+#### BEAM\_FORMAT\_NUMBER ####
+
+`genop.tab` has the following definition:
+
+    BEAM_FORMAT_NUMBER=0
+
+It defines the version of the instruction set (which will be
+included in the code header in the BEAM code).  Theoretically,
+the version could be bumped, and all instructions changed.
+In practice, we would have two support two instruction sets
+in the runtime system for at least two releases, so it will
+probably never happen in practice.
+
+#### GC\_REGEXP ####
+
+In `macros.tab`, there is a definition of `GC_REGEXP`.
+It will be described in [a later section](#the-gc_regexp-definition).
+
+### Directives ###
+
+There are directives to classify specific instructions depending
+on how frequently used they are:
+
+* `%hot` - Implementation will be placed in `beam_hot.h`. Frequently
+executed instructions.
+
+* `%warm` - Implementation will be placed in `beam_warm.h`.  Binary
+syntax instructions.
+
+* `%cold` - Implementation will be placed in `beam_cold.h`. Trace
+instructions and infrequently used instructions.
+
+Default is `%hot`.  The directives will be applied to declarations
+of the specific instruction that follow.  Here is an example:
+
+    %cold
+    is_number f? xy
+    %hot
+
+#### Conditional compilation directives ####
+
+The `%if` directive includes a range of lines if a condition is
+true.  For example:
+
+    %if ARCH_64
+    i_bs_get_integer_32 x f? x
+    %endif
+
+The specific instruction `i_bs_get_integer_32` will only be defined
+on a 64-bit machine.
+
+The condition can be inverted by using `%unless` instead of `%if`:
+
+    %unless NO_FPE_SIGNALS
+    fcheckerror p => i_fcheckerror
+    i_fcheckerror
+    fclearerror
+    %endif
+
+It is also possible to add an `%else` clause:
+
+    %if ARCH_64
+    BS_SAFE_MUL(A, B, Fail, Dst) {
+        Uint64 res = ($A) * ($B);
+        if (res / $B != $A) {
+            $Fail;
+        }
+        $Dst = res;
+    }
+    %else
+    BS_SAFE_MUL(A, B, Fail, Dst) {
+        Uint64 res = (Uint64)($A) * (Uint64)($B);
+        if ((res >> (8*sizeof(Uint))) != 0) {
+            $Fail;
+        }
+        $Dst = res;
+    }
+    %endif
+
+#### Symbols that are defined in directives ####
+
+The following symbols are always defined.
+
+* `ARCH_64` - is 1 for a 64-bit machine, and 0 otherwise.
+* `ARCH_32` - is 1 for 32-bit machine, and 1 otherwise.
+
+The `Makefile` for building the emulator currently defines the
+following symbols by using the `-D` option on the command line for
+**beam\_makeops**.
+
+* `NO_FPE_SIGNALS` - 1 if FPE signals are not enable in runtime system,
+0 otherwise.
+* `USE_VM_PROBES` - 1 if the runtime system is compiled to use VM probes (support for dtrace or systemtap), 0 otherwise.
+
+### Defining external generic instructions ###
+
+External generic BEAM instructions are known to both the compiler and
+the runtime system.  They remain stable between releases.  A new major
+release may add more external generic instructions, but must not change
+the semantics for a previously defined instruction.
+
+The syntax for an external generic instruction is as follows:
+
+*opcode*: [-]*name*/*arity*
+
+*opcode* is an integer greater than or equal to 1.
+
+*name* is an identifier starting with a lowercase letter.  *arity* is
+an integer denoting the number of operands.
+
+*name* can optionally be preceded by `-` to indicate that it has been
+obsoleted.  The compiler is not allowed to generate BEAM files that
+use obsolete instructions and the loader will refuse to load BEAM
+files that use obsolete instructions.
+
+It only makes sense to define external generic instructions in the
+file `genop.tab` in `lib/compiler/src`, because the compiler must
+know about them in order to use them.
+
+New instructions must be added at the end of the file, with higher
+numbers than the previous instructions.
+
+### Defining internal generic instructions ###
+
+Internal generic instructions are known only to the runtime
+system and can be changed at any time without compatibility issues.
+
+There are two ways to define internal generic instructions:
+
+* Implicitly when a specific instruction is defined.  This is by far
+the most common way.  Whenever a specific instruction is created,
+**beam\_makeops** automatically creates an internal generic instruction
+if it does not previously exist.
+
+* Explicitly.  This is necessary only when a generic instruction does
+not have any corresponding specific instruction.
+
+The syntax for an internal generic instruction is as follows:
+
+*name*/*arity*
+
+*name* is an identifier starting with a lowercase letter.  *arity* is
+an integer denoting the number of operands.
+
+### About generic instructions in general ###
+
+Each generic instruction has an opcode.  The opcode is an integer,
+greater than or equal to 1. For an external generic instruction, it
+must be explicitly given `genop.tab`, while internal generic
+instructions are automatically numbered by **beam\_makeops**.
+
+The identity of a generic instruction is its name combined with its
+arity.  That means that it is allowed to define two distinct generic
+instructions having the same name but with different arities.  For
+example:
+
+    move_window/5
+    move_window/6
+
+Each operand of a generic instruction is tagged with its type.  A generic
+instruction can have one of the following types:
+
+* `x` - X register.
+
+* `y` - Y register.
+
+* `l` - Floating point register number.
+
+* `i` - Tagged literal integer.
+
+* `a` - Tagged literal atom.
+
+* `n` - NIL (`[]`, the empty list).
+
+* `q` - Literal that don't fit in a word, that is an object stored on
+the heap such as a list or tuple.  Any heap object type is supported,
+even types that don't have real literals such as external references.
+
+* `f` - Non-zero failure label.
+
+* `p` - Zero failure label.
+
+* `u` - Untagged integer that fits in a machine word.  It is used for many
+different purposes, such as the number of live registers in `test_heap/2`,
+as a reference to the export for `call_ext/2`, and as the flags operand for
+binary syntax instructions.  When the generic instruction is translated to a
+specific instruction, the type for the operand in the specific operation will
+tell the loader how to treat the operand.
+
+* `o` - Overflow.  If the value for an `u` operand does not fit in a machine
+word, the type of the operand will be changed to `o` (with no associated
+value).  Currently only used internally in the loader in the guard constraint
+function `binary_too_big()`.
+
+* `v` - Arity value.  Only used internally in the loader.
+
+
+### Defining specific instructions ###
+
+The specific instructions are known only to the runtime system and
+are the instructions that are actually executed.  They can be changed
+at any time without causing compatibility issues.
+
+A specific instruction can have at most 6 operands.
+
+A specific instruction is defined by first giving its name followed by
+the types for each operand.  For example:
+
+     move x y
+
+Internally, for example in the generated code and in the output from
+the BEAM disassembler, the instruction `move x y` will be called `move_xy`.
+
+The name for a specific instruction is an identifier starting with a
+lowercase letter.  A type is an lowercase or uppercase letter.
+
+All specific instructions with a given name must have the same number
+of operands. That is, the following is **not** allowed:
+
+     move x x
+     move x y x y
+
+Here follows the type letters that more or less directly corresponds
+to the types for generic instructions.
+
+* `x` - X register.  Will be loaded as a byte offset to the X register
+relative to the base of X register array.  (Can be packed with other
+operands.)
+
+* `y` - Y register.  Will be loaded as a byte offset to the Y register
+relative to the stack frame. (Can be packed with other operands.)
+
+* `r` - X register 0.  An implicit operand that will not be stored in
+the loaded code.
+
+* `l` - Floating point register number.  (Can be packed with other
+operands.)
+
+* `i` - Tagged literal integer (a SMALL that will fit in one word).
+
+* `a` - Tagged atom.
+
+* `n` - NIL or the empty list.  (Will not be stored in the loaded code.)
+
+* `q` - Tagged CONS or BOXED pointer.  That is, a term such as a list
+or tuple.  Any heap object type is supported, even types that don't
+have real literals such as external references.
+
+* `f` - Failure label (non-zero).  The target for a branch
+or call instruction.
+
+* `p` - The 0 failure label, meaning that an exception should be raised
+if the instruction fails.  (Will not be stored in the loaded code.)
+
+* `c` - Any literal term; that is, immediate literals such as SMALL,
+and CONS or BOXED pointers to literals.  (Can be used where the
+operand in the generic instruction has one of the types `i`, `a`, `n`,
+or `q`.)
+
+The types that follow do a type test of the operand at runtime; thus,
+they are generally more expensive in terms of runtime than the types
+described earlier.  However, those operand types are needed to avoid a
+combinatorial explosion in the number of specific instructions and
+overall code size of `process_main()`.
+
+* `s` - Tagged source: X register, Y register, or a literal term.  The
+tag will be tested at runtime to retrieve the value from an X
+register, a Y register, or simply use the value as a tagged Erlang
+term.  (Implementation note: An X register is tagged as a pid, and a Y
+register as a port.  Therefore the literal term must not contain a
+port or pid.)
+
+* `S` - Tagged source register (X or Y).  The tag will be tested at
+runtime to retrieve the value from an X register or a Y register.  Slighly
+cheaper than `s`.
+
+* `d` - Tagged destination register (X or Y).  The tag will be tested
+at runtime to set up a pointer to the destination register.  If the
+instrution performs a garbarge collection, it must use the
+`$REFRESH_GEN_DEST()` macro to refresh the pointer before storing to
+it (there are more details about that in a later section).
+
+* `j` - A failure label (combination of `f` and `p`).  If the branch target 0,
+an exception will be raised if instruction fails, otherwise control will be
+transfered to the target address.
+
+The types that follows are all applied to an operand that has the `u`
+type.
+
+* `t` - An untagged integer that will fit in 12 bits (0-4096).  It can be
+packed with other operands in a word.  Most often used as the number
+of live registers in instructions such as `test_heap`.
+
+* `I` - An untagged integer that will fit in 32 bits.  It can be
+packed with other operands in a word on a 64-bit system.
+
+* `W` - Untagged integer or pointer.  Not possible to pack with other
+operands.
+
+* `e` - Pointer to an export entry.  Use by call instructions that call
+other modules, such as `call_ext`.
+
+* `L` - A label.  Only used by the `label/1` instruction.
+
+* `b` - Pointer to BIF.  Used by instructions that BIFs, such as
+`call_bif`.
+
+* `A` - A tagged arityvalue.  Used in instructions that test the arity
+of a tuple.
+
+* `P` - A byte offset into a tuple.
+
+* `Q` - A byte offset into the stack.  Used for updating the frame
+pointer register.  Can be packed with other operands.
+
+When the loader translates a generic instruction a specific
+instruction, it will choose the most specific instruction that will
+fit the types.  Consider the following two instructions:
+
+    move c x
+    move n x
+
+The `c` operand can encode any literal value, including NIL.  The
+`n` operand only works for NIL.  If we have the generic instruction
+`{move,nil,{x,1}}`, the loader will translate it to `move_nx 1`
+because `move n x` is more specific.  `move_nx` could be slightly
+faster or smaller (depending on the architecture), because the `[]`
+is not stored explicitly as an operand.
+
+#### Syntactic sugar for specific instructions ####
+
+It is possible to specify more than one type letter for each operand.
+Here is an example:
+
+    move cxy xy
+
+This is syntactic sugar for:
+
+    move c x
+    move c y
+    move x x
+    move x y
+    move y x
+    move y y
+
+Note the difference between `move c xy` and `move c d`.  Note that `move c xy`
+is equivalent to the following two definitions:
+
+    move c x
+    move c y
+
+On the other hand, `move c d` is a single instruction.  At runtime,
+the `d` operand will be tested to see whether it refers to an X
+register or a Y register, and a pointer to the register will be set
+up.
+
+#### The '?' type modifier ####
+
+The character `?` can be added to the end of an operand to indicate
+that the operand will not be used every time the instruction is executed.
+For example:
+
+    allocate_heap t I t?
+    is_eq_exact f? x xy
+
+In `allocate_heap`, the last operand is the number of live registers.
+It will only be used if there is not enough heap space and a garbage
+collection must be performed.
+
+In `is_eq_exact`, the failure address (the first operand) will only be
+used if the two register operands are not equal.
+
+Knowing that an operand is not always used can improve how packing
+is done for some instructions.
+
+For the `allocate_heap` instruction, without the `?` the packing would
+be done like this:
+
+         +--------------------+--------------------+
+    I -> |       Stack needed | &&lb_allocate_heap +
+         +--------------------+--------------------+
+         |        Heap needed | Live registers     +
+         +--------------------+--------------------+
+
+"Stack needed" and "Heap needed" are always used, but they are in
+different words.  Thus, at runtime the `allocate_heap` instruction
+must read both words from memory even though it will not always use
+"Live registers".
+
+With the `?`, the operands will be packed like this:
+
+         +--------------------+--------------------+
+    I -> |     Live registers | &&lb_allocate_heap +
+         +--------------------+--------------------+
+         |        Heap needed |       Stack needed +
+         +--------------------+--------------------+
+
+Now "Stack needed" and "Heap needed" are in the same word.
+
+### Defining transformation rules ###
+
+Transformation rules are used to rewrite generic instructions to other
+generic instructions.  The transformations rules are applied
+repeatedly until no rule match.  At that point, the first instruction
+in the resulting instruction sequence will be converted to a specific
+instruction and added to the code for the module being loaded.  Then
+the transformation rules for the remaining instructions are run in the
+same way.
+
+A rule is recognized by its right-pointer arrow: `=>`.  To the left of
+the arrow is one or more instruction patterns, separated by `|`.  To
+the right of the arrow is zero or more instructions, separated by `|`.
+If the instructions from the BEAM code matches the instruction
+patterns on the left side, they will be replaced with instructions on
+the right side (or removed if there are no instructions on the right).
+
+#### Defining instruction patterns ####
+
+We will start looking at the patterns on the left side of the arrow.
+
+A pattern for an instruction consists of its name, followed by a pattern
+for each of its operands.  The operand patterns are separated by spaces.
+
+The simplest possible pattern is a variable.  Just like in Erlang,
+a variable must begin with an uppercase letter.  If the same variable is
+used in multiple operands, the pattern will only match if the operands
+are equal.  For example:
+
+    move Same Same =>
+
+This pattern will match if the operands for `move` are the same.  If
+the pattern match, the instruction will be removed.  (That used to be an
+actual rule a long time ago when the compiler would occasionally produce
+instructions such as `{move,{x,2},{x,2}}`.)
+
+Variables that have been bound on the left side can be used on the
+right side.  For example, this rule will rewrite all `move` instructions
+to `assign` instructions with the operands swapped:
+
+    move Src Dst => assign Dst Src
+
+If we only want to match operands of a certain type, we can
+use a type constraint.  A type constraint consists of one or more
+lowercase letters, each specifying a type.  For example:
+
+    is_integer Fail an => jump Fail
+
+The second operand pattern, `an`, will match if the second operand is
+either an atom or NIL (the empty list).  In case of a match, the
+`is_integer/2` instruction will be replaced with a `jump/1`
+instruction.
+
+An operand pattern can bind a variable and constrain the type at the
+same time by following the variable with a `=` and the constraint.
+For example:
+
+    is_eq_exact Fail=f R=xy C=q => i_is_eq_exact_literal Fail R C
+
+Here the `is_eq_exact` instruction is replaced with a specialized instruction
+that only compares literals, but only if the first operand is a register and
+the second operand is a literal.
+
+#### Further constraining patterns ####
+
+In addition to specifying a type letter, the actual value for the type can
+be specified.  For example:
+
+    move C=c x==1 => move_x1 C
+
+Here the second operand of `move` is constrained to be X register 1.
+
+When specifying an atom constraint, the atom is written as it would be
+in the C source code.  That is, it needs an `am_` prefix, and it must
+be listed in `atom.names`.  For example:
+
+    is_boolean Fail=f a==am_true =>
+    is_boolean Fail=f a==am_false =>
+
+There are several constraints available for testing whether a call is to a BIF
+or a function.
+
+The constraint `u$is_bif` will test whether the given operand refers to a BIF.
+For example:
+
+    call_ext u Bif=u$is_bif => call_bif Bif
+    call_ext u Func         => i_call_ext Func
+
+The `call_ext` instruction can be used to call functions written in
+Erlang as well as BIFs (or more properly called SNIFs).  The
+`u$is_bif` constraint will match if the operand refers to a BIF (that
+is, if it is listed in the file `bif.tab`).  Note that `u$is_bif`
+should only be applied to operands that are known to contain an index
+to the import table chunk in the BEAM file (such operands have the
+type `b` or `e` in the corresponding specific instruction).  If
+applied to other `u` operands, it will at best return a nonsense
+result.
+
+The `u$is_not_bif` constraint matches if the operand does not refer to
+a BIF (not listed in `bif.tab`).  For example:
+
+    move S X0=x==0 | line Loc | call_ext_last Ar Func=u$is_not_bif D => \
+         move S X0 | call_ext_last Ar Func D
+
+The `u$bif:Module:Name/Arity` constraint tests whether the given
+operand refers to a specific BIF.  Note that `Module:Name/Arity`
+**must** be an existing BIF defined in `bif.tab`, or there will
+be a compilation error.  It is useful when a call to a specific BIF
+should be replaced with an instruction as in this example:
+
+    gc_bif2 Fail Live u$bif:erlang:splus/2 S1 S2 Dst => \
+         gen_plus Fail Live S1 S2 Dst
+
+Here the call to the GC BIF `'+'/2` will be replaced with the instruction
+`gen_plus/5`.  Note that the same name as used in the C source code must be
+used for the BIF, which in this case is `splus`.  It is defined like this
+in `bit.tab`:
+
+    ubif erlang:'+'/2 splus_2
+
+The `u$func:Module:Name/Arity` will test whether the given operand is a
+a specific function.  Here is an example:
+
+    bif1 Fail u$func:erlang:is_constant/1 Src Dst => too_old_compiler
+
+`is_constant/1` used to be a BIF a long time ago.  The transformation
+replaces the call with the `too_old_compiler` instruction which will produce
+a nicer error message than the default error would be for a missing guard BIF.
+
+#### Type constraints allowed in patterns ####
+
+Here are all type letters that are allowed on the left side of a transformation
+rule.
+
+* `u` - An untagged integer that fits in a machine word.
+
+* `x` - X register.
+
+* `y` - Y register.
+
+* `l` - Floating point register number.
+
+* `i` - Tagged literal integer.
+
+* `a` - Tagged literal atom.
+
+* `n` - NIL (`[]`, the empty list).
+
+* `q` - Literals that don't fit in a word, such as list or tuples.
+
+* `f` - Non-zero failure label.
+
+* `p` - The zero failure label.
+
+* `j` - Any label.  Equivalent to `fp`.
+
+* `c` - Any literal term.  Equivalent to `ainq`.
+
+* `s` - X register, Y register, or any literal term.  Equivalent to `xyc`.
+
+* `d` - X or Y register.  Equivalent to `xy`.  (In a pattern `d` will
+match both source and destination registers.  As an operand in a specific
+instruction, it must only be used for a destination register.)
+
+* `o` - Overflow.  An untagged integer that does not fit in a machine word.
+
+#### Guard constraints ####
+
+If the constraints described so far is not enough, additional
+constraints can be written in C in `beam_load.c` and be called as a
+guard function on the left side of the transformation.  If the guard
+function returns a non-zero value, the matching of the rule will
+continue, otherwise the match will fail.  For example:
+
+    ensure_map Lit=q | literal_is_map(Lit) =>
+
+The guard test `literal_is_map/1` tests whether the given literal is a map.
+If the literal is a map, the instruction is unnecessary and can be removed.
+
+It is outside the scope for this document to describe in detail how such
+guard functions are written, but for the curious here is the implementation
+of `literal_is_map()`:
+
+    static int
+    literal_is_map(LoaderState* stp, GenOpArg Lit)
+    {
+        Eterm term;
+
+        ASSERT(Lit.type == TAG_q);
+        term = stp->literals[Lit.val].term;
+        return is_map(term);
+    }
+
+#### Handling instruction with variable number of operands ####
+
+Some instructions, such as `select_val/3`, essentially has a variable
+number of operands.  Such instructions have a `{list,[...]}` operand
+as their last operand in the BEAM assembly code.  For example:
+
+    {select_val,{x,0},
+                {f,1},
+                {list,[{atom,b},{f,4},{atom,a},{f,5}]}}.
+
+The loader will convert a `{list,[...]}` operand to an `u` operand whose
+value is the number of elements in the list, followed by each element in
+the list.  The instruction above would be translated to the following
+generic instruction:
+
+    {select_val,{x,0},{f,1},{u,4},{atom,b},{f,4},{atom,a},{f,5}}
+
+To match a variable number of arguments we need to use the special
+operand type `*` like this:
+
+    select_val Src=aiq Fail=f Size=u List=* => \
+        i_const_select_val Src Fail Size List
+
+This transformation renames a `select_val/3` instruction
+with a constant source operand to `i_const_select_val/3`.
+
+#### Constructing new instructions on the right side ####
+
+The most common operand on the right side is a variable that was bound while
+matching the left side.  For example:
+
+    trim N Remaining => i_trim N
+
+An operand can also be a type letter to construct an operand of that type.
+Each type has a default value.  For example, the type `x` has the default
+value 1023, which is the highest X register.  That makes `x` on the right
+side a convenient shortcut for a temporary X register.  For example:
+
+    is_number Fail Literal=q => move Literal x | is_number Fail x
+
+If the second operand for `is_number/2` is a literal, it will be moved to
+X register 1023.  Then `is_number/2` will test whether the value stored in
+X register 1023 is a number.
+
+This kind of transformation is useful when it is rare that an operand can
+be anything else but a register.  In the case of `is_number/2`, the second
+operand is always a register unless the compiler optimizations have been
+disabled.
+
+If the default value is not suitable, the type letter can be followed
+by `=` and a value.  Most types take an integer value.  The value for
+an atom is written the same way as in the C source code.  For example,
+the atom `false` is written as `am_false`.  The atom must be listed in
+`atom.names`.
+
+Here is an example showing how values can be specified:
+
+    bs_put_utf32 Fail=j Flags=u Src=s => \
+        i_bs_validate_unicode Fail Src | \
+        bs_put_integer Fail i=32 u=1 Flags Src
+
+#### Type letters on the right side ####
+
+Here follows all types that are allowed to be used in operands for
+instructions being constructed on the right side of a transformation
+rule.
+
+* `u` - Construct an untagged integer.  The default value is 0.
+
+* `x` - X register.  The default value is 1023.  That makes `x` convenient to
+use as a temporary X register.
+
+* `y` - Y register.  The default value is 0.
+
+* `l` - Foating point register number.  The default value is 0.
+
+* `i` - Tagged literal integer.  The default value is 0.
+
+* `a` - Tagged atom.  The default value is the empty atom (`am_Empty`).
+
+* `n` - NIL (`[]`, the empty list).
+
+#### Function call on the right side ####
+
+Transformations that are not possible to describe with the rule
+language as described here can be written as a C function in
+`beam_load.c` and called from the right side of a transformation.  The
+left side of the transformation will perform the match and bind
+operands to variables.  The variables can then be passed to a
+generator function on the right side.  For example:
+
+    bif2 Fail=j u$bif:erlang:element/2 Index=s Tuple=xy Dst=d => \
+        gen_element(Jump, Index, Tuple, Dst)
+
+This transformation rule matches a call to the BIF `element/2`.
+The operands will be captured and the function `gen_element()` will
+be called.
+
+`gen_element()` will produce one of two instructions depending
+on `Index`.  If `Index` is an integer in the range from 1 up to
+the maximum tuple size, the instruction `i_fast_element/2` will
+be produced, otherwise the instruction `i_element/4` will be
+produced.  The corresponding specific instructions are:
+
+    i_fast_element xy j? I d
+    i_element xy j? s d
+
+The `i_fast_element/2` instruction is faster because the tuple is
+already an untagged integer.  It also knows that the index is at least
+1, so it does not have to test for that.  The `i_element/4`
+instruction will have to fetch the index from a register, test that it
+is an integer, and untag the integer.
+
+It is outside the scope of this document to describe in detail how
+generator functions are written, but for the curious, here is the
+implementation of `gen_element()`:
+
+    static GenOp*
+    gen_element(LoaderState* stp, GenOpArg Fail,
+       GenOpArg Index, GenOpArg Tuple, GenOpArg Dst)
+    {
+        GenOp* op;
+
+        NEW_GENOP(stp, op);
+        op->arity = 4;
+        op->next = NULL;
+
+        if (Index.type == TAG_i && Index.val > 0 &&
+           Index.val <= ERTS_MAX_TUPLE_SIZE &&
+           (Tuple.type == TAG_x || Tuple.type == TAG_y)) {
+            op->op = genop_i_fast_element_4;
+            op->a[0] = Tuple;
+            op->a[1] = Fail;
+            op->a[2].type = TAG_u;
+            op->a[2].val = Index.val;
+            op->a[3] = Dst;
+        } else {
+            op->op = genop_i_element_4;
+            op->a[0] = Tuple;
+            op->a[1] = Fail;
+            op->a[2] = Index;
+            op->a[3] = Dst;
+        }
+
+        return op;
+    }
+}
+
+### Defining the implementation ###
+
+The actual implementation of instructions are also defined in `.tab`
+files processed by **beam\_makeops**.  For practical reasons,
+instruction definitions are stored in several files, at the time of
+writing in the following files:
+
+    bif_instrs.tab
+    arith_instrs.tab
+    bs_instrs.tab
+    float_instrs.tab
+    instrs.tab
+    map_instrs.tab
+    msg_instrs.tab
+    select_instrs.tab
+    trace_instrs.tab
+
+There is also a file that only contains macro definitions:
+
+    macros.tab
+
+The syntax of each file is similar to C code.  In fact, most of
+the contents *is* C code, interspersed with macro invocations.
+
+To allow Emacs to auto-indent the code, each file starts with the
+following line:
+
+    // -*- c -*-
+
+To avoid messing up the indentation, all comments are written
+as C++ style comments (`//`) instead of `#`.  Note that a comment
+must start at the beginning of a line.
+
+The meat of an instruction definition file are macro definitions.
+We have seen this macro definition before:
+
+    move(Src, Dst) {
+        $Dst = $Src;
+    }
+
+A macro definitions must start at the beginning of the line (no spaces
+allowed), the opening curly bracket must be on the same line, and the
+finishing curly bracket must be at the beginning of a line.  It is
+recommended that the macro body is properly indented.
+
+As a convention, the macro arguments in the head all start with an
+uppercase letter.  In the body, the macro arguments can be expanded
+by preceding them with `$`.
+
+A macro definition whose name and arity matches a family of
+specific instructions is assumed to be the implementation of that
+instruction.
+
+A macro can also be invoked from within another macro.  For example,
+`move_deallocate_return/2` avoids repeating code by invoking
+`$deallocate_return()` as a macro:
+
+    move_deallocate_return(Src, Deallocate) {
+        x(0) = $Src;
+        $deallocate_return($Deallocate);
+    }
+
+Here is the definition of `deallocate_return/1`:
+
+    deallocate_return(Deallocate) {
+        //| -no_next
+        int words_to_pop = $Deallocate;
+        SET_I((BeamInstr *) cp_val(*E));
+        E = ADD_BYTE_OFFSET(E, words_to_pop);
+        CHECK_TERM(x(0));
+        DispatchReturn;
+    }
+
+The expanded code for `move_deallocate_return` will look this:
+
+    OpCase(move_deallocate_return_cQ):
+    {
+      x(0) = I[1];
+      do {
+        int words_to_pop = Qb(BeamExtraData(I[0]));
+        SET_I((BeamInstr *) cp_val(*E));
+        E = ADD_BYTE_OFFSET(E, words_to_pop);
+        CHECK_TERM(x(0));
+        DispatchReturn;
+      } while (0);
+    }
+
+When expanding macros, **beam\_makeops** wraps the expansion in a
+`do`/`while` wrapper unless **beam\_makeops** can clearly see that no
+wrapper is needed.  In this case, the wrapper is needed.
+
+Note that arguments for macros cannot be complex expressions, because
+the arguments are split on `,`.  For example, the following would
+not work because **beam\_makeops** would split the expression into
+two arguments:
+
+    $deallocate_return(get_deallocation(y, $Deallocate));
+
+#### Code generation directives ####
+
+Within macro definitions, `//` comments are in general not treated
+specially.  They will be copied to the file with the generated code
+along with the rest of code in the body.
+
+However, there is an exception. Within a macro definition, a line that
+starts with whitespace followed by `//|` is treated specially.  The
+rest of the line is assumed to contain directives to control code
+generation.
+
+Currently, two code generation directives are recognized:
+
+* `-no_prefetch`
+* `-no_next`
+
+##### The -no_prefetch directive #####
+
+To see what `-no_prefetch` does, let's first look at the default code
+generation.  Here is the code generated for `move_cx`:
+
+    OpCase(move_cx):
+    {
+      BeamInstr next_pf = BeamCodeAddr(I[2]);
+      xb(BeamExtraData(I[0])) = I[1];
+      I += 2;
+      ASSERT(VALID_INSTR(next_pf));
+      GotoPF(next_pf);
+    }
+
+Note that the very first thing done is to fetch the address to the
+next instruction.  The reason is that it usually improves performance.
+
+Just as a demonstration, we can add a `-no_prefetch` directive to
+the `move/2` instruction:
+
+    move(Src, Dst) {
+        //| -no_prefetch
+        $Dst = $Src;
+    }
+
+We can see that the prefetch is no longer done:
+
+    OpCase(move_cx):
+    {
+      xb(BeamExtraData(I[0])) = I[1];
+      I += 2;
+      ASSERT(VALID_INSTR(*I));
+      Goto(*I);
+    }
+
+When would we want to turn off the prefetch in practice?
+
+In instructions that will not always execute the next instruction.
+For example:
+
+    is_atom(Fail, Src) {
+        if (is_not_atom($Src)) {
+            $FAIL($Fail);
+        }
+    }
+
+    // From macros.tab
+    FAIL(Fail) {
+        //| -no_prefetch
+        $SET_I_REL($Fail);
+        Goto(*I);
+    }
+
+`is_atom/2` may either execute the next instruction (if the second
+operand is an atom) or branch to the failure label.
+
+The generated code looks like this:
+
+    OpCase(is_atom_fx):
+    {
+      if (is_not_atom(xb(I[1]))) {
+        ASSERT(VALID_INSTR(*(I + (fb(BeamExtraData(I[0]))) + 0)));
+        I += fb(BeamExtraData(I[0])) + 0;;
+        Goto(*I);;
+      }
+      I += 2;
+      ASSERT(VALID_INSTR(*I));
+      Goto(*I);
+    }
+
+##### The -no_next directive #####
+
+Next we will look at when the `-no_next` directive can be used.  Here
+is the `jump/1` instruction:
+
+    jump(Fail) {
+        $JUMP($Fail);
+    }
+
+    // From macros.tab
+    JUMP(Fail) {
+        //| -no_next
+        $SET_I_REL($Fail);
+        Goto(*I);
+    }
+
+The generated code looks like this:
+
+    OpCase(jump_f):
+    {
+      ASSERT(VALID_INSTR(*(I + (fb(BeamExtraData(I[0]))) + 0)));
+      I += fb(BeamExtraData(I[0])) + 0;;
+      Goto(*I);;
+    }
+
+If we remove the `-no_next` directive, the code would look like this:
+
+    OpCase(jump_f):
+    {
+      BeamInstr next_pf = BeamCodeAddr(I[1]);
+      ASSERT(VALID_INSTR(*(I + (fb(BeamExtraData(I[0]))) + 0)));
+      I += fb(BeamExtraData(I[0])) + 0;;
+      Goto(*I);;
+      I += 1;
+      ASSERT(VALID_INSTR(next_pf));
+      GotoPF(next_pf);
+    }
+
+In the end, the C compiler will probably optimize this code to the
+same native code as the first version, but the first version is certainly
+much easier to read for human readers.
+
+#### Macros in the macros.tab file ####
+
+The file `macros.tab` contains many useful macros.  When implementing
+new instructions it is good practice to look through `macros.tab` to
+see if any of existing macros can be used rather than re-inventing
+the wheel.
+
+We will describe a few of the most useful macros here.
+
+##### The GC_REGEXP definition #####
+
+The following line defines a regular expression that will recognize
+a call to a function that does a garbage collection:
+
+     GC_REGEXP=erts_garbage_collect|erts_gc|GcBifFunction;
+
+The purpose is that **beam\_makeops** can verify that an instruction
+that does a garbage collection and has an `d` operand uses the
+`$REFRESH_GEN_DEST()` macro.
+
+If you need to define a new function that does garbage collection,
+you should give it the prefix `erts_gc_`.  If that is not possible
+you should update the regular expression so that it will match your
+new function.
+
+##### FAIL(Fail) #####
+
+Branch to `$Fail`.  Will suppress prefetch (`-no_prefetch`).  Typical use:
+
+    is_nonempty_list(Fail, Src) {
+        if (is_not_list($Src)) {
+            $FAIL($Fail);
+        }
+    }
+
+##### JUMP(Fail) #####
+
+Branch to `$Fail`.  Suppresses generation of dispatch of the next
+instruction (`-no_next`).  Typical use:
+
+    jump(Fail) {
+        $JUMP($Fail);
+    }
+
+##### GC_TEST(NeedStack, NeedHeap, Live) #####
+
+`$GC_TEST(NeedStack, NeedHeap, Live)` tests that given amount of
+stack space and heap space is available.  If not it will do a
+garbage collection.  Typical use:
+
+    test_heap(Nh, Live) {
+        $GC_TEST(0, $Nh, $Live);
+    }
+
+##### AH(NeedStack, NeedHeap, Live) #####
+
+`AH(NeedStack, NeedHeap, Live)` allocates a stack frame and
+optionally additional heap space.
+
+#### Pre-defined macros and variables ####
+
+**beam\_makeops** defines several built-in macros and pre-bound variables.
+
+##### The NEXT_INSTRUCTION pre-bound variable #####
+
+The NEXT_INSTRUCTION is a pre-bound variable that is available in
+all instructions.  It expands to the address of the next instruction.
+
+Here is an example:
+
+    i_call(CallDest) {
+        SET_CP(c_p, $NEXT_INSTRUCTION);
+        $DISPATCH_REL($CallDest);
+    }
+
+When calling a function, the return address is first stored in `c_p->cp`
+(using the `SET_CP()` macro defined in `beam_emu.c`), and then control is
+transferred to the callee.  Here is the generated code:
+
+    OpCase(i_call_f):
+    {
+      SET_CP(c_p, I+1);
+      ASSERT(VALID_INSTR(*(I + (fb(BeamExtraData(I[0]))) + 0)));
+      I += fb(BeamExtraData(I[0])) + 0;;
+      DTRACE_LOCAL_CALL(c_p, erts_code_to_codemfa(I));
+      Dispatch();;
+    }
+
+We can see that that `$NEXT_INSTRUCTION` has been expanded to `I+1`.
+That makes sense since the size of the `i_call_f/1` instruction is
+one word.
+
+##### The IP_ADJUSTMENT pre-bound variable #####
+
+`$IP_ADJUSTMENT` is usually 0.  In a few combined instructions
+(described below) it can be non-zero.  It is used like this
+in `macros.tab`:
+
+    SET_I_REL(Offset) {
+        ASSERT(VALID_INSTR(*(I + ($Offset) + $IP_ADJUSTMENT)));
+        I += $Offset + $IP_ADJUSTMENT;
+    }
+
+Avoid using `IP_ADJUSTMENT` directly.  Use `SET_I_REL()` or
+one of the macros that invoke such as `FAIL()` or `JUMP()`
+defined in `macros.tab`.
+
+#### Pre-defined macro functions ####
+
+##### The IF() macro #####
+
+`$IF(Expr, IfTrue, IfFalse)` evaluates `Expr`, which must be a valid
+Perl expression (which for simple numeric expressions have the same
+syntax as C).  If `Expr` evaluates to 0, the entire `IF()` expression will be
+replaced with `IfFalse`, otherwise it will be replaced with `IfTrue`.
+
+See the description of `OPERAND_POSITION()` for an example.
+
+##### The OPERAND\_POSITION() macro #####
+
+`$OPERAND_POSITION(Expr)` returns the position for `Expr`, if
+`Expr` is an operand that is not packed.  The first operand is
+at position 1.
+
+Returns 0 otherwise.
+
+This macro could be used like this in order to share code:
+
+    FAIL(Fail) {
+        //| -no_prefetch
+        $IF($OPERAND_POSITION($Fail) == 1 && $IP_ADJUSTMENT == 0,
+            goto common_jump,
+            $DO_JUMP($Fail));
+    }
+
+    DO_JUMP(Fail) {
+        $SET_I_REL($Fail);
+        Goto(*I));
+    }
+
+    // In beam_emu.c:
+    common_jump:
+       I += I[1];
+       Goto(*I));
+
+
+#### The $REFRESH\_GEN\_DEST() macro ####
+
+When a specific instruction has a `d` operand, early during execution
+of the instruction, a pointer will be initialized to point to the X or
+Y register in question.
+
+If there is a garbage collection before the result is stored,
+the stack will move and if the `d` operand refered to a Y
+register, the pointer will no longer be valid.  (Y registers are
+stored on the stack.)
+
+In those circumstances, `$REFRESH_GEN_DEST()` must be invoked
+to set up the pointer again.  **beam\_makeops** will notice
+if there is a call to a function that does a garbage collection and
+`$REFRESH_GEN_DEST()` is not called.
+
+Here is a complete example.  The `new_map` instruction is defined
+like this:
+
+    new_map d t I
+
+It is implemented like this:
+
+    new_map(Dst, Live, N) {
+        Eterm res;
+
+        HEAVY_SWAPOUT;
+        res = erts_gc_new_map(c_p, reg, $Live, $N, $NEXT_INSTRUCTION);
+        HEAVY_SWAPIN;
+        $REFRESH_GEN_DEST();
+        $Dst = res;
+        $NEXT($NEXT_INSTRUCTION+$N);
+    }
+
+If we have forgotten the `$REFRESH_GEN_DEST()` there would be a message
+similar to this:
+
+    pointer to destination register is invalid after GC -- use $REFRESH_GEN_DEST()
+    ... from the body of new_map at beam/map_instrs.tab(30)
+
+#### Combined instructions ####
+
+**Problem**: For frequently executed instructions we want to use
+"fast" operands types such as `x` and `y`, as opposed to `s` or `S`.
+To avoid an explosion in code size, we want to share most of the
+implementation between the instructions.  Here are the specific
+instructions for `i_increment/5`:
+
+    i_increment r W t d
+    i_increment x W t d
+    i_increment y W t d
+
+The `i_increment` instruction is implemented like this:
+
+    i_increment(Source, IncrementVal, Live, Dst) {
+        Eterm increment_reg_source = $Source;
+        Eterm increment_val = $IncrementVal;
+        Uint live;
+        Eterm result;
+
+        if (ERTS_LIKELY(is_small(increment_reg_val))) {
+            Sint i = signed_val(increment_reg_val) + increment_val;
+            if (ERTS_LIKELY(IS_SSMALL(i))) {
+                $Dst = make_small(i);
+                $NEXT0();
+            }
+        }
+        live = $Live;
+        HEAVY_SWAPOUT;
+        reg[live] = increment_reg_val;
+        reg[live+1] = make_small(increment_val);
+        result = erts_gc_mixed_plus(c_p, reg, live);
+        HEAVY_SWAPIN;
+        ERTS_HOLE_CHECK(c_p);
+        if (ERTS_LIKELY(is_value(result))) {
+            $REFRESH_GEN_DEST();
+            $Dst = result;
+            $NEXT0();
+        }
+        ASSERT(c_p->freason != BADMATCH || is_value(c_p->fvalue));
+        goto find_func_info;
+    }
+
+There will be three almost identical copies of the code.  Given the
+size of the code, that could be too high cost to pay.
+
+To avoid the three copies of the code, we could use only one specific
+instruction:
+
+    i_increment S W t d
+
+(The same implementation as above will work.)
+
+That reduces the code size, but is slower because `S` means that
+there will be extra code to test whether the operand refers to an X
+register or a Y register.
+
+**Solution**: We can use "combined instructions".  Combined
+instructions are combined from instruction fragments.  The
+bulk of the code can be shared.
+
+Here we will show how `i_increment` can be implemented as a combined
+instruction.  We will show each individual fragment first, and then
+show how to connect them together.  First we will need a variable that
+we can store the value fetched from the register in:
+
+    increment.head() {
+        Eterm increment_reg_val;
+    }
+
+The name `increment` is the name of the group that the fragment
+belongs to.  Note that it does not need to have the same
+name as the instruction.  The group name is followed by `.` and
+the name of the fragment.  The name `head` is pre-defined.
+The code in it will be placed at the beginning of a block, so
+that all fragments in the group can access it.
+
+Next we define the fragment that will pick up the value from the
+register from the first operand:
+
+    increment.fetch(Src) {
+        increment_reg_val = $Src;
+    }
+
+We call this fragment `fetch`.  This fragment will be duplicated three
+times, one for each value of the first operand (`r`, `x`, and `y`).
+
+Next we define the main part of the code that do the actual incrementing.
+
+    increment.execute(IncrementVal, Live, Dst) {
+        Eterm increment_val = $IncrementVal;
+        Uint live;
+        Eterm result;
+
+        if (ERTS_LIKELY(is_small(increment_reg_val))) {
+            Sint i = signed_val(increment_reg_val) + increment_val;
+            if (ERTS_LIKELY(IS_SSMALL(i))) {
+                $Dst = make_small(i);
+                $NEXT0();
+            }
+        }
+        live = $Live;
+        HEAVY_SWAPOUT;
+        reg[live] = increment_reg_val;
+        reg[live+1] = make_small(increment_val);
+        result = erts_gc_mixed_plus(c_p, reg, live);
+        HEAVY_SWAPIN;
+        ERTS_HOLE_CHECK(c_p);
+        if (ERTS_LIKELY(is_value(result))) {
+            $REFRESH_GEN_DEST();
+            $Dst = result;
+            $NEXT0();
+        }
+        ASSERT(c_p->freason != BADMATCH || is_value(c_p->fvalue));
+        goto find_func_info;
+    }
+
+We call this fragment `execute`.  It will handle the three remaining
+operands (`W t d`).  There will only be one copy of this fragment.
+
+Now that we have defined the fragments, we need to inform
+**beam\_makeops** how they should be connected:
+
+    i_increment := increment.fetch.execute;
+
+To the left of the `:=` is the name of the specific instruction that
+should be implemented by the fragments, in this case `i_increment`.
+To the right of `:=` is the name of the group with the fragments,
+followed by a `.`.  Then the name of the fragments in the group are
+listed in the order they should be executed.  Note that the `head`
+fragment is not listed.
+
+The line ends in `;` (to avoid messing up the indentation in Emacs).
+
+(Note that in practice the `:=` line is usually placed before the
+fragments.)
+
+The generated code looks like this:
+
+    {
+      Eterm increment_reg_val;
+      OpCase(i_increment_rWtd):
+      {
+        increment_reg_val = r(0);
+      }
+      goto increment__execute;
+
+      OpCase(i_increment_xWtd):
+      {
+        increment_reg_val = xb(BeamExtraData(I[0]));
+      }
+      goto increment__execute;
+
+      OpCase(i_increment_yWtd):
+      {
+        increment_reg_val = yb(BeamExtraData(I[0]));
+      }
+      goto increment__execute;
+
+      increment__execute:
+      {
+        // Here follows the code from increment.execute()
+        .
+        .
+        .
+    }
+
+##### Some notes about combined instructions #####
+
+The operands that are different must be at
+the beginning of the instruction.  All operands in the last
+fragment must have the same operands in all variants of
+the specific instruction.
+
+As an example, the following specific instructions cannot be
+implemented as a combined instruction:
+
+    i_times j? t x x d
+    i_times j? t x y d
+    i_times j? t s s d
+
+We would have to change the order of the operands so that the
+two operands that are different are placed first:
+
+    i_times x x j? t d
+    i_times x y j? t d
+    i_times s s j? t d
+
+We can then define:
+
+    i_times := times.fetch.execute;
+
+    times.head {
+        Eterm op1, op2;
+    }
+
+    times.fetch(Src1, Src2) {
+        op1 = $Src1;
+        op2 = $Src2;
+    }
+
+    times.execute(Fail, Live, Dst) {
+        // Multiply op1 and op2.
+        .
+        .
+        .
+    }
+
+Several instructions can share a group.  As an example, the following
+instructions have different names, but in the end they all create a
+binary.  The last two operands are common for all of them:
+
+    i_bs_init_fail       xy j? t? x
+    i_bs_init_fail_heap s I j? t? x
+    i_bs_init                W t? x
+    i_bs_init_heap         W I t? x
+
+The instructions are defined like this (formatted with extra
+spaces for clarity):
+
+    i_bs_init_fail_heap := bs_init . fail_heap . verify . execute;
+    i_bs_init_fail      := bs_init . fail      . verify . execute;
+    i_bs_init           := bs_init .           .  plain . execute;
+    i_bs_init_heap      := bs_init .               heap . execute;
+
+Note that the first two instruction have three fragments, while the
+other two only have two fragments.  Here are the fragments:
+
+    bs_init_bits.head() {
+        Eterm num_bits_term;
+        Uint num_bits;
+        Uint alloc;
+    }
+
+    bs_init_bits.plain(NumBits) {
+        num_bits = $NumBits;
+        alloc = 0;
+    }
+
+    bs_init_bits.heap(NumBits, Alloc) {
+        num_bits = $NumBits;
+        alloc = $Alloc;
+    }
+
+    bs_init_bits.fail(NumBitsTerm) {
+        num_bits_term = $NumBitsTerm;
+        alloc = 0;
+    }
+
+    bs_init_bits.fail_heap(NumBitsTerm, Alloc) {
+        num_bits_term = $NumBitsTerm;
+        alloc = $Alloc;
+    }
+
+    bs_init_bits.verify(Fail) {
+        // Verify the num_bits_term, fail using $FAIL
+        // if there is a problem.
+	.
+	.
+	.
+    }
+
+    bs_init_bits.execute(Live, Dst) {
+       // Long complicated code to a create a binary.
+       .
+       .
+       .
+    }
+
+The full definitions of those instructions can be found in `bs_instrs.tab`.
+The generated code can be found in `beam_warm.h`.
diff --git a/erts/emulator/internal_doc/figures/.gitignore b/erts/emulator/internal_doc/figures/.gitignore
new file mode 100644
index 0000000000..c2813ac866
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/.gitignore
@@ -0,0 +1 @@
+*.eps
\ No newline at end of file
diff --git a/erts/emulator/internal_doc/figures/Makefile b/erts/emulator/internal_doc/figures/Makefile
new file mode 100644
index 0000000000..111cb393fb
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/Makefile
@@ -0,0 +1,20 @@
+# In order to update the figures you have to have both dia
+# and imagemagick installed.
+
+DIAGRAMS=$(wildcard *.dia)
+EPS_DIAGRAMS=$(patsubst %.dia,%.eps,$(DIAGRAMS))
+PNG_DIAGRAMS=$(patsubst %.dia,%.png,$(DIAGRAMS))
+
+diagrams: $(EPS_DIAGRAMS)
+
+png: $(PNG_DIAGRAMS)
+
+update_png: png
+	git add $(PNG_DIAGRAMS)
+	git commit -m "Update internal docs figures"
+
+%.eps: %.dia
+	dia --export=$@ $<
+
+%.png: %.eps
+	convert $< -resize 65% $@
diff --git a/erts/emulator/internal_doc/figures/gc-heap-scan1.dia b/erts/emulator/internal_doc/figures/gc-heap-scan1.dia
new file mode 100644
index 0000000000..b8a32dc092
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/gc-heap-scan1.dia
diff --git a/erts/emulator/internal_doc/figures/gc-heap-scan1.png b/erts/emulator/internal_doc/figures/gc-heap-scan1.png
new file mode 100644
index 0000000000..9724fc8698
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/gc-heap-scan1.png
diff --git a/erts/emulator/internal_doc/figures/gc-heap-stop.dia b/erts/emulator/internal_doc/figures/gc-heap-stop.dia
new file mode 100644
index 0000000000..af219958c6
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/gc-heap-stop.dia
diff --git a/erts/emulator/internal_doc/figures/gc-heap-stop.png b/erts/emulator/internal_doc/figures/gc-heap-stop.png
new file mode 100644
index 0000000000..ec79790d36
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/gc-heap-stop.png
diff --git a/erts/emulator/internal_doc/figures/gc-rootset-scan.dia b/erts/emulator/internal_doc/figures/gc-rootset-scan.dia
new file mode 100644
index 0000000000..d6147740e5
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/gc-rootset-scan.dia
diff --git a/erts/emulator/internal_doc/figures/gc-rootset-scan.png b/erts/emulator/internal_doc/figures/gc-rootset-scan.png
new file mode 100644
index 0000000000..06509f83c3
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/gc-rootset-scan.png
diff --git a/erts/emulator/internal_doc/figures/gc-start.dia b/erts/emulator/internal_doc/figures/gc-start.dia
new file mode 100644
index 0000000000..41832d29b0
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/gc-start.dia
diff --git a/erts/emulator/internal_doc/figures/gc-start.png b/erts/emulator/internal_doc/figures/gc-start.png
new file mode 100644
index 0000000000..6c29e9adb0
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/gc-start.png
diff --git a/erts/emulator/internal_doc/figures/gc-watermark-2.dia b/erts/emulator/internal_doc/figures/gc-watermark-2.dia
new file mode 100644
index 0000000000..2ea3be3fb2
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/gc-watermark-2.dia
diff --git a/erts/emulator/internal_doc/figures/gc-watermark-2.png b/erts/emulator/internal_doc/figures/gc-watermark-2.png
new file mode 100644
index 0000000000..bca110282d
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/gc-watermark-2.png
diff --git a/erts/emulator/internal_doc/figures/gc-watermark.dia b/erts/emulator/internal_doc/figures/gc-watermark.dia
new file mode 100644
index 0000000000..a5de7565dc
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/gc-watermark.dia
diff --git a/erts/emulator/internal_doc/figures/gc-watermark.png b/erts/emulator/internal_doc/figures/gc-watermark.png
new file mode 100644
index 0000000000..b835c7694e
--- /dev/null
+++ b/erts/emulator/internal_doc/figures/gc-watermark.png
diff --git a/erts/emulator/nifs/common/prim_buffer_nif.c b/erts/emulator/nifs/common/prim_buffer_nif.c
new file mode 100644
index 0000000000..a8ef5fc355
--- /dev/null
+++ b/erts/emulator/nifs/common/prim_buffer_nif.c
@@ -0,0 +1,512 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson 2017. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+#define STATIC_ERLANG_NIF 1
+
+#include "erl_nif.h"
+#include "config.h"
+#include "sys.h"
+
+#ifdef VALGRIND
+#  include <valgrind/memcheck.h>
+#endif
+
+#define ACCUMULATOR_SIZE (2 << 10)
+
+#define FIND_NIF_RESCHEDULE_SIZE (1 << 20)
+
+/* NIF interface declarations */
+static int load(ErlNifEnv *env, void** priv_data, ERL_NIF_TERM load_info);
+static int upgrade(ErlNifEnv *env, void** priv_data, void** old_priv_data, ERL_NIF_TERM load_info);
+static void unload(ErlNifEnv *env, void* priv_data);
+
+static ErlNifResourceType *rtype_buffer;
+
+static ERL_NIF_TERM am_ok;
+static ERL_NIF_TERM am_error;
+
+static ERL_NIF_TERM am_lock_order_violation;
+
+static ERL_NIF_TERM am_acquired;
+static ERL_NIF_TERM am_busy;
+
+static ERL_NIF_TERM am_continue;
+
+static ERL_NIF_TERM am_out_of_memory;
+static ERL_NIF_TERM am_not_found;
+
+typedef struct {
+#ifdef DEBUG
+    erts_atomic32_t concurrent_users;
+#endif
+
+    ErlNifBinary accumulator;
+    size_t accumulated_bytes;
+    int accumulator_present;
+
+    ErlNifIOQueue *queue;
+
+    erts_atomic32_t external_lock;
+} buffer_data_t;
+
+static ERL_NIF_TERM new_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM peek_head_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM skip_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM size_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM write_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM copying_read_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM find_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM trylock_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM unlock_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ErlNifFunc nif_funcs[] = {
+    {"new", 0, new_nif},
+    {"size", 1, size_nif},
+    {"peek_head", 1, peek_head_nif},
+    {"copying_read", 2, copying_read_nif},
+    {"write", 2, write_nif},
+    {"skip", 2, skip_nif},
+    {"find_byte_index", 2, find_nif},
+    {"try_lock", 1, trylock_nif},
+    {"unlock", 1, unlock_nif},
+};
+
+ERL_NIF_INIT(prim_buffer, nif_funcs, load, NULL, upgrade, unload)
+
+static void gc_buffer(ErlNifEnv *env, void* data);
+
+static int load(ErlNifEnv *env, void** priv_data, ERL_NIF_TERM load_info)
+{
+    am_ok = enif_make_atom(env, "ok");
+    am_error = enif_make_atom(env, "error");
+
+    am_lock_order_violation = enif_make_atom(env, "lock_order_violation");
+    am_acquired = enif_make_atom(env, "acquired");
+    am_busy = enif_make_atom(env, "busy");
+
+    am_continue = enif_make_atom(env, "continue");
+
+    am_out_of_memory = enif_make_atom(env, "out_of_memory");
+    am_not_found = enif_make_atom(env, "not_found");
+
+    rtype_buffer = enif_open_resource_type(env, NULL, "gc_buffer", gc_buffer,
+        ERL_NIF_RT_CREATE, NULL);
+
+    *priv_data = NULL;
+
+    return 0;
+}
+
+static void unload(ErlNifEnv *env, void* priv_data)
+{
+
+}
+
+static int upgrade(ErlNifEnv *env, void** priv_data, void** old_priv_data, ERL_NIF_TERM load_info)
+{
+    if(*old_priv_data != NULL) {
+        return -1; /* Don't know how to do that */
+    }
+
+    if(*priv_data != NULL) {
+        return -1; /* Don't know how to do that */
+    }
+
+    if(load(env, priv_data, load_info)) {
+        return -1;
+    }
+
+    return 0;
+}
+
+static void gc_buffer(ErlNifEnv *env, void* data) {
+    buffer_data_t *buffer = (buffer_data_t*)data;
+
+    if(buffer->accumulator_present) {
+        enif_release_binary(&buffer->accumulator);
+    }
+
+    enif_ioq_destroy(buffer->queue);
+}
+
+static int get_buffer_data(ErlNifEnv *env, ERL_NIF_TERM opaque, buffer_data_t **buffer) {
+    return enif_get_resource(env, opaque, rtype_buffer, (void **)buffer);
+}
+
+/* Copies a number of bytes from the head of the iovec, skipping "vec_skip"
+ * vector elements followed by "byte_skip" bytes on the target vector. */
+static void copy_from_iovec(SysIOVec *iovec, int vec_len, int vec_skip,
+        size_t byte_skip, size_t size, char *data) {
+
+    size_t bytes_copied, skip_offset;
+    int vec_index;
+
+    skip_offset = byte_skip;
+    vec_index = vec_skip;
+    bytes_copied = 0;
+
+    while(bytes_copied < size) {
+        size_t block_size, copy_size;
+        char *block_start;
+
+        ASSERT(vec_index < vec_len);
+
+        block_start = (char*)iovec[vec_index].iov_base;
+        block_size = iovec[vec_index].iov_len;
+
+        copy_size = MIN(size - bytes_copied, block_size - skip_offset);
+        sys_memcpy(&data[bytes_copied], &block_start[skip_offset], copy_size);
+
+        bytes_copied += copy_size;
+        skip_offset = 0;
+
+        vec_index++;
+    }
+}
+
+/* Convenience function for copy_from_iovec over queues. */
+static void copy_from_queue(ErlNifIOQueue *queue, int queue_skip,
+    size_t byte_skip, size_t size, char *data) {
+
+    SysIOVec *queued_data;
+    int queue_length;
+
+    queued_data = enif_ioq_peek(queue, &queue_length);
+    ASSERT(queue_skip < queue_length);
+
+    copy_from_iovec(queued_data, queue_length, queue_skip, byte_skip, size, data);
+}
+
+static int enqueue_write_accumulator(buffer_data_t *buffer) {
+    ASSERT(!buffer->accumulator_present ^ (buffer->accumulated_bytes > 0));
+
+    if(buffer->accumulator_present && buffer->accumulated_bytes > 0) {
+        if(!enif_realloc_binary(&buffer->accumulator, buffer->accumulated_bytes)) {
+            return 0;
+        } else if(!enif_ioq_enq_binary(buffer->queue, &buffer->accumulator, 0)) {
+            return 0;
+        }
+
+        /* The queue owns the accumulator now. */
+        buffer->accumulator_present = 0;
+        buffer->accumulated_bytes = 0;
+    }
+
+    return 1;
+}
+
+static int combine_small_writes(buffer_data_t *buffer, ErlNifIOVec *iovec) {
+    ASSERT(!buffer->accumulator_present ^ (buffer->accumulated_bytes > 0));
+
+    if(buffer->accumulated_bytes + iovec->size >= ACCUMULATOR_SIZE) {
+        if(iovec->size >= (ACCUMULATOR_SIZE / 2)) {
+            return 0;
+        }
+
+        if(!enqueue_write_accumulator(buffer)) {
+            return 0;
+        }
+    }
+
+    if(!buffer->accumulator_present) {
+        if(!enif_alloc_binary(ACCUMULATOR_SIZE, &buffer->accumulator)) {
+            return 0;
+        }
+
+        buffer->accumulator_present = 1;
+    }
+
+    copy_from_iovec(iovec->iov, iovec->iovcnt, 0, 0, iovec->size,
+            (char*)&buffer->accumulator.data[buffer->accumulated_bytes]);
+    buffer->accumulated_bytes += iovec->size;
+
+    return 1;
+}
+
+/* *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** */
+
+static ERL_NIF_TERM new_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    buffer_data_t *buffer;
+    ERL_NIF_TERM result;
+
+    buffer = (buffer_data_t*)enif_alloc_resource(rtype_buffer, sizeof(buffer_data_t));
+    buffer->queue = enif_ioq_create(ERL_NIF_IOQ_NORMAL);
+
+    if(buffer->queue != NULL) {
+#ifdef DEBUG
+        erts_atomic32_init_nob(&buffer->concurrent_users, 0);
+#endif
+        erts_atomic32_init_nob(&buffer->external_lock, 0);
+
+        buffer->accumulator_present = 0;
+        buffer->accumulated_bytes = 0;
+
+        result = enif_make_resource(env, buffer);
+    } else {
+        result = enif_raise_exception(env, am_out_of_memory);
+    }
+
+    enif_release_resource(buffer);
+
+    return result;
+}
+
+static ERL_NIF_TERM size_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    buffer_data_t *buffer;
+
+    size_t total_size;
+
+    if(argc != 1 || !get_buffer_data(env, argv[0], &buffer)) {
+        return enif_make_badarg(env);
+    }
+
+    ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1);
+
+    total_size = enif_ioq_size(buffer->queue);
+
+    if(buffer->accumulator_present) {
+        total_size += buffer->accumulated_bytes;
+    } else {
+        ASSERT(buffer->accumulated_bytes == 0);
+    }
+
+    ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+    return enif_make_uint64(env, total_size);
+}
+
+static ERL_NIF_TERM copying_read_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    buffer_data_t *buffer;
+
+    ERL_NIF_TERM result;
+    unsigned char *data;
+    Uint64 block_size;
+
+    if(argc != 2 || !get_buffer_data(env, argv[0], &buffer)
+                 || !enif_get_uint64(env, argv[1], &block_size)) {
+        return enif_make_badarg(env);
+    }
+
+    ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1);
+
+    if(!enqueue_write_accumulator(buffer)) {
+        return enif_raise_exception(env, am_out_of_memory);
+    }
+
+    if(enif_ioq_size(buffer->queue) < block_size) {
+        return enif_make_badarg(env);
+    }
+
+    data = enif_make_new_binary(env, block_size, &result);
+
+    if(block_size > 0) {
+        copy_from_queue(buffer->queue, 0, 0, block_size, (char*)data);
+        enif_ioq_deq(buffer->queue, block_size, NULL);
+    }
+
+    ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+    return result;
+}
+
+static ERL_NIF_TERM write_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    buffer_data_t *buffer;
+
+    ErlNifIOVec vec, *iovec = &vec;
+    ERL_NIF_TERM tail;
+
+    if(argc != 2 || !get_buffer_data(env, argv[0], &buffer)
+                 || !enif_inspect_iovec(env, 64, argv[1], &tail, &iovec)) {
+        return enif_make_badarg(env);
+    }
+
+    ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1);
+
+    if(!combine_small_writes(buffer, iovec)) {
+        if(!enqueue_write_accumulator(buffer) || !enif_ioq_enqv(buffer->queue, iovec, 0)) {
+            return enif_raise_exception(env, am_out_of_memory);
+        }
+    }
+
+    ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+    if(!enif_is_empty_list(env, tail)) {
+        const ERL_NIF_TERM new_argv[2] = {argv[0], tail};
+
+        return enif_schedule_nif(env, "write", 0, &write_nif, argc, new_argv);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM peek_head_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    buffer_data_t *buffer;
+
+    ERL_NIF_TERM result;
+
+    if(argc != 1 || !get_buffer_data(env, argv[0], &buffer)) {
+        return enif_make_badarg(env);
+    }
+
+    ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1);
+
+    if(!enqueue_write_accumulator(buffer)) {
+        return enif_raise_exception(env, am_out_of_memory);
+    }
+
+    if(!enif_ioq_peek_head(env, buffer->queue, NULL, &result)) {
+        return enif_make_badarg(env);
+    }
+
+    ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+    return result;
+}
+
+static ERL_NIF_TERM skip_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    buffer_data_t *buffer;
+
+    Uint64 block_size;
+
+    if(argc != 2 || !get_buffer_data(env, argv[0], &buffer)
+                 || !enif_get_uint64(env, argv[1], &block_size)) {
+        return enif_make_badarg(env);
+    }
+
+    ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1);
+
+    if(!enqueue_write_accumulator(buffer)) {
+        return enif_raise_exception(env, am_out_of_memory);
+    } else if(enif_ioq_size(buffer->queue) < block_size) {
+        return enif_make_badarg(env);
+    }
+
+    enif_ioq_deq(buffer->queue, block_size, NULL);
+
+    ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM find_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    buffer_data_t *buffer;
+
+    int queue_length, queue_index;
+    SysIOVec *queued_data;
+    size_t queue_size;
+
+    size_t search_offset;
+    int needle;
+
+    if(argc != 2 || !get_buffer_data(env, argv[0], &buffer)
+                 || !enif_get_int(env, argv[1], &needle)) {
+        return enif_make_badarg(env);
+    }
+
+    ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1);
+
+    if(!enqueue_write_accumulator(buffer)) {
+        return enif_raise_exception(env, am_out_of_memory);
+    } else if(needle < 0 || needle > 255) {
+        return enif_make_badarg(env);
+    }
+
+    queued_data = enif_ioq_peek(buffer->queue, &queue_length);
+    queue_size = enif_ioq_size(buffer->queue);
+    queue_index = 0;
+
+    search_offset = 0;
+
+    if(queue_size > (FIND_NIF_RESCHEDULE_SIZE / 100)) {
+        if(enif_thread_type() == ERL_NIF_THR_NORMAL_SCHEDULER) {
+            int timeslice_percent;
+
+            if(queue_size >= FIND_NIF_RESCHEDULE_SIZE) {
+                ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+                return enif_schedule_nif(env, "find",
+                    ERL_NIF_DIRTY_JOB_CPU_BOUND, &find_nif, argc, argv);
+            }
+
+            timeslice_percent = (queue_size * 100) / FIND_NIF_RESCHEDULE_SIZE;
+            enif_consume_timeslice(env, timeslice_percent);
+        }
+    }
+
+    while(queue_index < queue_length) {
+        char *needle_address;
+        char *block_start;
+        size_t block_size;
+
+        block_start = queued_data[queue_index].iov_base;
+        block_size = queued_data[queue_index].iov_len;
+
+        needle_address = memchr(block_start, needle, block_size);
+
+        if(needle_address != NULL) {
+            size_t result = search_offset + (needle_address - block_start);
+
+            ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+            return enif_make_tuple2(env, am_ok, enif_make_uint64(env, result));
+        }
+
+        search_offset += block_size;
+        queue_index++;
+    }
+
+    ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+    return am_not_found;
+}
+
+/* */
+
+static ERL_NIF_TERM trylock_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    buffer_data_t *buffer;
+
+    if(argc != 1 || !get_buffer_data(env, argv[0], &buffer)) {
+        return enif_make_badarg(env);
+    }
+
+    if(erts_atomic32_cmpxchg_acqb(&buffer->external_lock, 1, 0) == 0) {
+        return am_acquired;
+    }
+
+    return am_busy;
+}
+
+static ERL_NIF_TERM unlock_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    buffer_data_t *buffer;
+
+    if(argc != 1 || !get_buffer_data(env, argv[0], &buffer)) {
+        return enif_make_badarg(env);
+    }
+
+    if(erts_atomic32_cmpxchg_relb(&buffer->external_lock, 0, 1) == 0) {
+        return enif_raise_exception(env, am_lock_order_violation);
+    }
+
+    return am_ok;
+}
diff --git a/erts/emulator/nifs/common/prim_file_nif.c b/erts/emulator/nifs/common/prim_file_nif.c
new file mode 100644
index 0000000000..6874f41d75
--- /dev/null
+++ b/erts/emulator/nifs/common/prim_file_nif.c
@@ -0,0 +1,1237 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson 2017. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+#define STATIC_ERLANG_NIF 1
+
+#include "erl_nif.h"
+#include "config.h"
+#include "sys.h"
+
+#ifdef VALGRIND
+#  include <valgrind/memcheck.h>
+#endif
+
+#include "erl_driver.h"
+#include "prim_file_nif.h"
+
+/* NIF interface declarations */
+static int load(ErlNifEnv *env, void** priv_data, ERL_NIF_TERM load_info);
+static int upgrade(ErlNifEnv *env, void** priv_data, void** old_priv_data, ERL_NIF_TERM load_info);
+static void unload(ErlNifEnv *env, void* priv_data);
+
+static ErlNifResourceType *efile_resource_type;
+
+static ERL_NIF_TERM am_ok;
+static ERL_NIF_TERM am_error;
+static ERL_NIF_TERM am_continue;
+
+static ERL_NIF_TERM am_file_info;
+
+/* File modes */
+static ERL_NIF_TERM am_read;
+static ERL_NIF_TERM am_write;
+static ERL_NIF_TERM am_exclusive;
+static ERL_NIF_TERM am_append;
+static ERL_NIF_TERM am_sync;
+static ERL_NIF_TERM am_skip_type_check;
+
+/* enum efile_access_t; read and write are defined above.*/
+static ERL_NIF_TERM am_read_write;
+static ERL_NIF_TERM am_none;
+
+/* enum efile_advise_t */
+static ERL_NIF_TERM am_normal;
+static ERL_NIF_TERM am_random;
+static ERL_NIF_TERM am_sequential;
+static ERL_NIF_TERM am_will_need;
+static ERL_NIF_TERM am_dont_need;
+static ERL_NIF_TERM am_no_reuse;
+
+/* enum efile_filetype_t */
+static ERL_NIF_TERM am_device;
+static ERL_NIF_TERM am_directory;
+static ERL_NIF_TERM am_regular;
+static ERL_NIF_TERM am_symlink;
+static ERL_NIF_TERM am_other;
+
+/* enum efile_seek_t, 'eof' marker. */
+static ERL_NIF_TERM am_bof;
+static ERL_NIF_TERM am_cur;
+static ERL_NIF_TERM am_eof;
+
+static ERL_NIF_TERM read_info_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM set_permissions_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM set_owner_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM set_time_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM read_link_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM list_dir_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM make_hard_link_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM make_soft_link_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM rename_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM make_dir_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM del_file_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM del_dir_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM get_device_cwd_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM get_cwd_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM set_cwd_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM read_file_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM get_handle_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM altname_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM open_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+/* All file handle operations are passed through a wrapper that handles state
+ * transitions, marking it as busy during the course of the operation, and
+ * closing on completion if the owner died in the middle of an operation.
+ *
+ * This is pretty ugly but required as there's no way to tell when it's safe to
+ * asynchronously close a file; the event could have fired just before landing
+ * in a system call which will fail with EBADF at best or alias a newly opened
+ * fd at worst.
+ *
+ * The old driver got away with enqueueing the close operation on the same
+ * async queue as all of its other operations, but since dirty schedulers use a
+ * single global queue there's no natural way to schedule an asynchronous close
+ * "behind" other operations.
+ *
+ * The states may transition as follows:
+ *
+ * IDLE ->
+ *      BUSY (file_handle_wrapper) |
+ *      CLOSED (owner_death_callback)
+ *
+ * BUSY ->
+ *      IDLE (file_handle_wrapper)
+ *      CLOSED (close_nif_impl)
+ *      CLOSE_PENDING (owner_death_callback)
+ *
+ * CLOSE_PENDING ->
+ *      CLOSED (file_handle_wrapper)
+ */
+
+typedef ERL_NIF_TERM (*file_op_impl_t)(efile_data_t *d, ErlNifEnv *env,
+    int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM file_handle_wrapper(file_op_impl_t operation, ErlNifEnv *env,
+    int argc, const ERL_NIF_TERM argv[]);
+
+#define WRAP_FILE_HANDLE_EXPORT(name) \
+    static ERL_NIF_TERM name ## _impl (efile_data_t *d, ErlNifEnv *env, \
+        int argc, const ERL_NIF_TERM argv[]);\
+    static ERL_NIF_TERM name(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) { \
+        return file_handle_wrapper( name ## _impl , env, argc, argv); \
+    }
+
+WRAP_FILE_HANDLE_EXPORT(close_nif)
+WRAP_FILE_HANDLE_EXPORT(read_nif)
+WRAP_FILE_HANDLE_EXPORT(write_nif)
+WRAP_FILE_HANDLE_EXPORT(pread_nif)
+WRAP_FILE_HANDLE_EXPORT(pwrite_nif)
+WRAP_FILE_HANDLE_EXPORT(seek_nif)
+WRAP_FILE_HANDLE_EXPORT(sync_nif)
+WRAP_FILE_HANDLE_EXPORT(truncate_nif)
+WRAP_FILE_HANDLE_EXPORT(allocate_nif)
+WRAP_FILE_HANDLE_EXPORT(advise_nif)
+WRAP_FILE_HANDLE_EXPORT(get_handle_nif)
+WRAP_FILE_HANDLE_EXPORT(ipread_s32bu_p32bu_nif)
+
+static ErlNifFunc nif_funcs[] = {
+    /* File handle ops */
+    {"open_nif", 2, open_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"close_nif", 1, close_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"read_nif", 2, read_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"write_nif", 2, write_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"pread_nif", 3, pread_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"pwrite_nif", 3, pwrite_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"seek_nif", 3, seek_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"sync_nif", 2, sync_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"truncate_nif", 1, truncate_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"allocate_nif", 3, allocate_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"advise_nif", 4, advise_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+
+    /* Filesystem ops */
+    {"make_hard_link_nif", 2, make_hard_link_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"make_soft_link_nif", 2, make_soft_link_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"rename_nif", 2, rename_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"read_info_nif", 2, read_info_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"set_permissions_nif", 2, set_permissions_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"set_owner_nif", 3, set_owner_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"set_time_nif", 4, set_time_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"read_link_nif", 1, read_link_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"list_dir_nif", 1, list_dir_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"make_dir_nif", 1, make_dir_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"del_file_nif", 1, del_file_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"del_dir_nif", 1, del_dir_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"get_device_cwd_nif", 1, get_device_cwd_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"set_cwd_nif", 1, set_cwd_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"get_cwd_nif", 0, get_cwd_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+
+    /* These operations are equivalent to chained calls of other operations,
+     * but have been moved down to avoid excessive rescheduling. */
+    {"ipread_s32bu_p32bu_nif", 3, ipread_s32bu_p32bu_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+    {"read_file_nif", 1, read_file_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+
+    /* Internal ops. */
+    {"get_handle_nif", 1, get_handle_nif},
+    {"altname_nif", 1, altname_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+};
+
+ERL_NIF_INIT(prim_file, nif_funcs, load, NULL, upgrade, unload)
+
+static void owner_death_callback(ErlNifEnv* env, void* obj, ErlNifPid* pid, ErlNifMonitor* mon);
+static void gc_callback(ErlNifEnv *env, void* data);
+
+static int load(ErlNifEnv *env, void** priv_data, ERL_NIF_TERM load_info)
+{
+    ErlNifResourceTypeInit callbacks;
+
+    am_ok = enif_make_atom(env, "ok");
+    am_error = enif_make_atom(env, "error");
+    am_continue = enif_make_atom(env, "continue");
+
+    am_read = enif_make_atom(env, "read");
+    am_write = enif_make_atom(env, "write");
+    am_exclusive = enif_make_atom(env, "exclusive");
+    am_append = enif_make_atom(env, "append");
+    am_sync = enif_make_atom(env, "sync");
+    am_skip_type_check = enif_make_atom(env, "skip_type_check");
+
+    am_read_write = enif_make_atom(env, "read_write");
+    am_none = enif_make_atom(env, "none");
+
+    am_normal = enif_make_atom(env, "normal");
+    am_random = enif_make_atom(env, "random");
+    am_sequential = enif_make_atom(env, "sequential");
+    am_will_need = enif_make_atom(env, "will_need");
+    am_dont_need = enif_make_atom(env, "dont_need");
+    am_no_reuse = enif_make_atom(env, "no_reuse");
+
+    am_device = enif_make_atom(env, "device");
+    am_directory = enif_make_atom(env, "directory");
+    am_regular = enif_make_atom(env, "regular");
+    am_symlink = enif_make_atom(env, "symlink");
+    am_other = enif_make_atom(env, "other");
+
+    am_file_info = enif_make_atom(env, "file_info");
+
+    am_bof = enif_make_atom(env, "bof");
+    am_cur = enif_make_atom(env, "cur");
+    am_eof = enif_make_atom(env, "eof");
+
+    callbacks.down = owner_death_callback;
+    callbacks.dtor = gc_callback;
+    callbacks.stop = NULL;
+
+    efile_resource_type = enif_open_resource_type_x(env, "efile", &callbacks,
+        ERL_NIF_RT_CREATE, NULL);
+
+    *priv_data = NULL;
+
+    return 0;
+}
+
+static void unload(ErlNifEnv *env, void* priv_data)
+{
+
+}
+
+static int upgrade(ErlNifEnv *env, void** priv_data, void** old_priv_data, ERL_NIF_TERM load_info)
+{
+    if(*old_priv_data != NULL) {
+        return -1; /* Don't know how to do that */
+    }
+    if(*priv_data != NULL) {
+        return -1; /* Don't know how to do that */
+    }
+    if(load(env, priv_data, load_info)) {
+        return -1;
+    }
+    return 0;
+}
+
+static ERL_NIF_TERM posix_error_to_tuple(ErlNifEnv *env, posix_errno_t posix_errno) {
+    ERL_NIF_TERM error = enif_make_atom(env, erl_errno_id(posix_errno));
+    return enif_make_tuple2(env, am_error, error);
+}
+
+static int get_file_data(ErlNifEnv *env, ERL_NIF_TERM opaque, efile_data_t **d) {
+    return enif_get_resource(env, opaque, efile_resource_type, (void **)d);
+}
+
+static ERL_NIF_TERM file_handle_wrapper(file_op_impl_t operation, ErlNifEnv *env,
+        int argc, const ERL_NIF_TERM argv[]) {
+
+    efile_data_t *d;
+
+    enum efile_state_t previous_state;
+    ERL_NIF_TERM result;
+
+    if(argc < 1 || !get_file_data(env, argv[0], &d)) {
+        return enif_make_badarg(env);
+    }
+
+    previous_state = erts_atomic32_cmpxchg_acqb(&d->state,
+        EFILE_STATE_BUSY, EFILE_STATE_IDLE);
+
+    if(previous_state == EFILE_STATE_IDLE) {
+        result = operation(d, env, argc - 1, &argv[1]);
+
+        previous_state = erts_atomic32_cmpxchg_relb(&d->state,
+            EFILE_STATE_IDLE, EFILE_STATE_BUSY);
+
+        ASSERT(previous_state != EFILE_STATE_IDLE);
+
+        if(previous_state == EFILE_STATE_CLOSE_PENDING) {
+            /* This is the only point where a change from CLOSE_PENDING is
+             * possible, and we're running synchronously, so we can't race with
+             * anything else here. */
+            erts_atomic32_set_acqb(&d->state, EFILE_STATE_CLOSED);
+            efile_close(d);
+        }
+    } else {
+        /* CLOSE_PENDING should be impossible at this point since it requires
+         * a transition from BUSY; the only valid state here is CLOSED. */
+        ASSERT(previous_state == EFILE_STATE_CLOSED);
+
+        result = posix_error_to_tuple(env, EINVAL);
+    }
+
+    return result;
+}
+
+static void owner_death_callback(ErlNifEnv* env, void* obj, ErlNifPid* pid, ErlNifMonitor* mon) {
+    efile_data_t *d = (efile_data_t*)obj;
+
+    (void)env;
+    (void)pid;
+    (void)mon;
+
+    for(;;) {
+        enum efile_state_t previous_state;
+
+        previous_state = erts_atomic32_cmpxchg_acqb(&d->state,
+            EFILE_STATE_CLOSED, EFILE_STATE_IDLE);
+
+        switch(previous_state) {
+        case EFILE_STATE_IDLE:
+            efile_close(d);
+            return;
+        case EFILE_STATE_CLOSE_PENDING:
+        case EFILE_STATE_CLOSED:
+            /* We're either already closed or managed to mark ourselves for
+             * closure in the previous iteration. */
+            return;
+        case EFILE_STATE_BUSY:
+            /* Schedule ourselves to be closed once the current operation
+             * finishes, retrying the [IDLE -> CLOSED] transition in case we
+             * narrowly passed the [BUSY -> IDLE] one. */
+            erts_atomic32_cmpxchg_nob(&d->state,
+                EFILE_STATE_CLOSE_PENDING, EFILE_STATE_BUSY);
+            break;
+        }
+    }
+}
+
+static void gc_callback(ErlNifEnv *env, void* data) {
+    efile_data_t *d = (efile_data_t*)data;
+
+    enum efile_state_t previous_state;
+
+    (void)env;
+
+    previous_state = erts_atomic32_cmpxchg_acqb(&d->state,
+        EFILE_STATE_CLOSED, EFILE_STATE_IDLE);
+
+    ASSERT(previous_state != EFILE_STATE_CLOSE_PENDING &&
+        previous_state != EFILE_STATE_BUSY);
+
+    if(previous_state == EFILE_STATE_IDLE) {
+        efile_close(d);
+    }
+}
+
+static ERL_NIF_TERM efile_filetype_to_atom(enum efile_filetype_t type) {
+    switch(type) {
+        case EFILE_FILETYPE_DEVICE: return am_device;
+        case EFILE_FILETYPE_DIRECTORY: return am_directory;
+        case EFILE_FILETYPE_REGULAR: return am_regular;
+        case EFILE_FILETYPE_SYMLINK: return am_symlink;
+        case EFILE_FILETYPE_OTHER: return am_other;
+    }
+
+    return am_other;
+}
+
+static ERL_NIF_TERM efile_access_to_atom(enum efile_access_t type) {
+    if(type & EFILE_ACCESS_READ && !(type & EFILE_ACCESS_WRITE)) {
+        return am_read;
+    } else if(type & EFILE_ACCESS_WRITE && !(type & EFILE_ACCESS_READ)) {
+        return am_write;
+    } else if(type & EFILE_ACCESS_READ_WRITE) {
+        return am_read_write;
+    }
+
+    return am_none;
+}
+
+static enum efile_modes_t efile_translate_modelist(ErlNifEnv *env, ERL_NIF_TERM list) {
+    enum efile_modes_t modes;
+    ERL_NIF_TERM head, tail;
+
+    modes = 0;
+
+    while(enif_get_list_cell(env, list, &head, &tail)) {
+        if(enif_is_identical(head, am_read)) {
+            modes |= EFILE_MODE_READ;
+        } else if(enif_is_identical(head, am_write)) {
+            modes |= EFILE_MODE_WRITE;
+        } else if(enif_is_identical(head, am_exclusive)) {
+            modes |= EFILE_MODE_EXCLUSIVE;
+        } else if(enif_is_identical(head, am_append)) {
+            modes |= EFILE_MODE_APPEND;
+        } else if(enif_is_identical(head, am_sync)) {
+            modes |= EFILE_MODE_SYNC;
+        } else if(enif_is_identical(head, am_skip_type_check)) {
+            modes |= EFILE_MODE_SKIP_TYPE_CHECK;
+        } else {
+            /* Modes like 'raw', 'ram', 'delayed_writes' etc are handled
+             * further up the chain. */
+        }
+
+        list = tail;
+    }
+
+    if(modes & (EFILE_MODE_APPEND | EFILE_MODE_EXCLUSIVE)) {
+        /* 'append' and 'exclusive' are documented as "open for writing." */
+        modes |= EFILE_MODE_WRITE;
+    } else if(!(modes & EFILE_MODE_READ_WRITE)) {
+        /* Defaulting to read if !(W|R) is undocumented, but specifically
+         * tested against in file_SUITE. */
+        modes |= EFILE_MODE_READ;
+    }
+
+    return modes;
+}
+
+static ERL_NIF_TERM open_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+    efile_data_t *d;
+
+    ErlNifPid controlling_process;
+    enum efile_modes_t modes;
+    ERL_NIF_TERM result;
+    efile_path_t path;
+
+    if(argc != 2 || !enif_is_list(env, argv[1])) {
+        return enif_make_badarg(env);
+    }
+
+    modes = efile_translate_modelist(env, argv[1]);
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_open(&path, modes, efile_resource_type, &d))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    result = enif_make_resource(env, d);
+    enif_release_resource(d);
+
+    enif_self(env, &controlling_process);
+
+    if(enif_monitor_process(env, d, &controlling_process, &d->monitor)) {
+        return posix_error_to_tuple(env, EINVAL);
+    }
+
+    return enif_make_tuple2(env, am_ok, result);
+}
+
+static ERL_NIF_TERM close_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    enum efile_state_t previous_state;
+
+    if(argc != 0) {
+        return enif_make_badarg(env);
+    }
+
+    previous_state = erts_atomic32_cmpxchg_acqb(&d->state,
+        EFILE_STATE_CLOSED, EFILE_STATE_BUSY);
+
+    ASSERT(previous_state == EFILE_STATE_CLOSE_PENDING ||
+        previous_state == EFILE_STATE_BUSY);
+
+    if(previous_state == EFILE_STATE_BUSY) {
+        enif_demonitor_process(env, d, &d->monitor);
+
+        if(!efile_close(d)) {
+            return posix_error_to_tuple(env, d->posix_errno);
+        }
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM read_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    Sint64 bytes_read, block_size;
+    SysIOVec read_vec[1];
+    ErlNifBinary result;
+
+    if(argc != 1 || !enif_is_number(env, argv[0])) {
+        return enif_make_badarg(env);
+    }
+
+    if(!enif_get_int64(env, argv[0], &block_size) || block_size < 0) {
+        return posix_error_to_tuple(env, EINVAL);
+    }
+
+    if(!enif_alloc_binary(block_size, &result)) {
+        return posix_error_to_tuple(env, ENOMEM);
+    }
+
+    read_vec[0].iov_base = result.data;
+    read_vec[0].iov_len = result.size;
+
+    bytes_read = efile_readv(d, read_vec, 1);
+    ASSERT(bytes_read <= block_size);
+
+    if(bytes_read < 0) {
+        return posix_error_to_tuple(env, d->posix_errno);
+    } else if(bytes_read == 0) {
+        enif_release_binary(&result);
+        return am_eof;
+    }
+
+    if(bytes_read < block_size && !enif_realloc_binary(&result, bytes_read)) {
+        ERTS_INTERNAL_ERROR("Failed to shrink read result.");
+    }
+
+    return enif_make_tuple2(env, am_ok, enif_make_binary(env, &result));
+}
+
+static ERL_NIF_TERM write_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    ErlNifIOVec vec, *input = &vec;
+    Sint64 bytes_written;
+    ERL_NIF_TERM tail;
+
+    if(argc != 1 || !enif_inspect_iovec(env, 64, argv[0], &tail, &input)) {
+        return enif_make_badarg(env);
+    }
+
+    bytes_written = efile_writev(d, input->iov, input->iovcnt);
+
+    if(bytes_written < 0) {
+        return posix_error_to_tuple(env, d->posix_errno);
+    }
+
+    if(!enif_is_empty_list(env, tail)) {
+        ASSERT(bytes_written > 0);
+        return enif_make_tuple2(env, am_continue, tail);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM pread_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    Sint64 bytes_read, block_size, offset;
+    SysIOVec read_vec[1];
+    ErlNifBinary result;
+
+    if(argc != 2 || !enif_is_number(env, argv[0])
+                 || !enif_is_number(env, argv[1])) {
+        return enif_make_badarg(env);
+    }
+
+    if(!enif_get_int64(env, argv[0], &offset) ||
+       !enif_get_int64(env, argv[1], &block_size) ||
+       (offset < 0 || block_size < 0)) {
+        return posix_error_to_tuple(env, EINVAL);
+    }
+
+    if(!enif_alloc_binary(block_size, &result)) {
+        return posix_error_to_tuple(env, ENOMEM);
+    }
+
+    read_vec[0].iov_base = result.data;
+    read_vec[0].iov_len = result.size;
+
+    bytes_read = efile_preadv(d, offset, read_vec, 1);
+
+    if(bytes_read < 0) {
+        return posix_error_to_tuple(env, d->posix_errno);
+    } else if(bytes_read == 0) {
+        enif_release_binary(&result);
+        return am_eof;
+    }
+
+    if(bytes_read < block_size && !enif_realloc_binary(&result, bytes_read)) {
+        ERTS_INTERNAL_ERROR("Failed to shrink pread result.");
+    }
+
+    return enif_make_tuple2(env, am_ok, enif_make_binary(env, &result));
+}
+
+static ERL_NIF_TERM pwrite_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    ErlNifIOVec vec, *input = &vec;
+    Sint64 bytes_written, offset;
+    ERL_NIF_TERM tail;
+
+    if(argc != 2 || !enif_is_number(env, argv[0])
+                 || !enif_inspect_iovec(env, 64, argv[1], &tail, &input)) {
+        return enif_make_badarg(env);
+    }
+
+    if(!enif_get_int64(env, argv[0], &offset) || offset < 0) {
+        return posix_error_to_tuple(env, EINVAL);
+    }
+
+    bytes_written = efile_pwritev(d, offset, input->iov, input->iovcnt);
+
+    if(bytes_written < 0) {
+        return posix_error_to_tuple(env, d->posix_errno);
+    }
+
+    if(!enif_is_empty_list(env, tail)) {
+        ASSERT(bytes_written > 0);
+        return enif_make_tuple3(env, am_continue,
+            enif_make_int64(env, bytes_written), tail);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM seek_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    Sint64 new_position, offset;
+    enum efile_seek_t seek;
+
+    if(argc != 2 || !enif_get_int64(env, argv[1], &offset)) {
+        return enif_make_badarg(env);
+    }
+
+    if(enif_is_identical(argv[0], am_bof)) {
+        seek = EFILE_SEEK_BOF;
+    } else if(enif_is_identical(argv[0], am_cur)) {
+        seek = EFILE_SEEK_CUR;
+    } else if(enif_is_identical(argv[0], am_eof)) {
+        seek = EFILE_SEEK_EOF;
+    } else {
+        return enif_make_badarg(env);
+    }
+
+    if(!efile_seek(d, seek, offset, &new_position)) {
+        return posix_error_to_tuple(env, d->posix_errno);
+    }
+
+    return enif_make_tuple2(env, am_ok, enif_make_uint64(env, new_position));
+}
+
+static ERL_NIF_TERM sync_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    int data_only;
+
+    if(argc != 1 || !enif_get_int(env, argv[0], &data_only)) {
+        return enif_make_badarg(env);
+    }
+
+    if(!efile_sync(d, data_only)) {
+        return posix_error_to_tuple(env, d->posix_errno);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM truncate_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    if(argc != 0) {
+        return enif_make_badarg(env);
+    }
+
+    if(!efile_truncate(d)) {
+        return posix_error_to_tuple(env, d->posix_errno);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM allocate_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    Sint64 offset, length;
+
+    if(argc != 2 || !enif_is_number(env, argv[0])
+                 || !enif_is_number(env, argv[1])) {
+        return enif_make_badarg(env);
+    }
+
+    if(!enif_get_int64(env, argv[0], &offset) ||
+       !enif_get_int64(env, argv[1], &length) ||
+       (offset < 0 || length < 0)) {
+        return posix_error_to_tuple(env, EINVAL);
+    }
+
+    if(!efile_allocate(d, offset, length)) {
+        return posix_error_to_tuple(env, d->posix_errno);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM advise_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    enum efile_advise_t advise;
+    Sint64 offset, length;
+
+    if(argc != 3 || !enif_is_number(env, argv[0])
+                 || !enif_is_number(env, argv[1])) {
+        return enif_make_badarg(env);
+    }
+
+    if(!enif_get_int64(env, argv[0], &offset) ||
+       !enif_get_int64(env, argv[1], &length) ||
+       (offset < 0 || length < 0)) {
+        return posix_error_to_tuple(env, EINVAL);
+    }
+
+    if(enif_is_identical(argv[2], am_normal)) {
+        advise = EFILE_ADVISE_NORMAL;
+    } else if(enif_is_identical(argv[2], am_random)) {
+        advise = EFILE_ADVISE_RANDOM;
+    } else if(enif_is_identical(argv[2], am_sequential)) {
+        advise = EFILE_ADVISE_SEQUENTIAL;
+    } else if(enif_is_identical(argv[2], am_will_need)) {
+        advise = EFILE_ADVISE_WILL_NEED;
+    } else if(enif_is_identical(argv[2], am_dont_need)) {
+        advise = EFILE_ADVISE_DONT_NEED;
+    } else if(enif_is_identical(argv[2], am_no_reuse)) {
+        advise = EFILE_ADVISE_NO_REUSE;
+    } else {
+        /* The tests check for EINVAL instead of badarg. Sigh. */
+        return posix_error_to_tuple(env, EINVAL);
+    }
+
+    if(!efile_advise(d, offset, length, advise)) {
+        return posix_error_to_tuple(env, d->posix_errno);
+    }
+
+    return am_ok;
+}
+
+/* This undocumented function reads a pointer and then reads the data block
+ * described by said pointer. It was reverse-engineered from the old
+ * implementation so while all tests pass it may not be entirely correct. Our
+ * current understanding is as follows:
+ *
+ * Pointer layout:
+ *
+ *     <<Size:1/integer-unit:32, Offset:1/integer-unit:32>>
+ *
+ * Where Offset is the -absolute- address to the data block.
+ *
+ * *) If we fail to read the pointer block in its entirety, we return eof.
+ * *) If the provided max_payload_size is larger than Size, we return eof.
+ * *) If we fail to read any data whatsoever at Offset, we return
+ *    {ok, {Size, Offset, eof}}
+ * *) Otherwise, we return {ok, {Size, Offset, Data}}. Note that the size
+ *    of Data may be smaller than Size if we encounter EOF before we could
+ *    read the entire block.
+ *
+ * On errors we'll return {error, posix()} regardless of whether they
+ * happened before or after reading the pointer block. */
+static ERL_NIF_TERM ipread_s32bu_p32bu_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    Sint64 payload_offset, payload_size;
+
+    SysIOVec read_vec[1];
+    Sint64 bytes_read;
+
+    ErlNifBinary payload;
+
+    if(argc != 2 || !enif_is_number(env, argv[0])
+                 || !enif_is_number(env, argv[1])) {
+        return enif_make_badarg(env);
+    }
+
+    {
+        Sint64 max_payload_size, pointer_offset;
+        unsigned char pointer_block[8];
+
+        if(!enif_get_int64(env, argv[0], &pointer_offset) ||
+           !enif_get_int64(env, argv[1], &max_payload_size) ||
+           (pointer_offset < 0 || max_payload_size >= 1u << 31)) {
+            return posix_error_to_tuple(env, EINVAL);
+        }
+
+        read_vec[0].iov_base = pointer_block;
+        read_vec[0].iov_len = sizeof(pointer_block);
+
+        bytes_read = efile_preadv(d, pointer_offset, read_vec, 1);
+
+        if(bytes_read < 0) {
+            return posix_error_to_tuple(env, d->posix_errno);
+        } else if(bytes_read < sizeof(pointer_block)) {
+            return am_eof;
+        }
+
+        payload_size = (Uint32)get_int32(&pointer_block[0]);
+        payload_offset = (Uint32)get_int32(&pointer_block[4]);
+
+        if(payload_size > max_payload_size) {
+            return am_eof;
+        }
+    }
+
+    if(!enif_alloc_binary(payload_size, &payload)) {
+        return posix_error_to_tuple(env, ENOMEM);
+    }
+
+    read_vec[0].iov_base = payload.data;
+    read_vec[0].iov_len = payload.size;
+
+    bytes_read = efile_preadv(d, payload_offset, read_vec, 1);
+
+    if(bytes_read < 0) {
+        return posix_error_to_tuple(env, d->posix_errno);
+    } else if(bytes_read == 0) {
+        enif_release_binary(&payload);
+
+        return enif_make_tuple2(env, am_ok,
+                enif_make_tuple3(env,
+                    enif_make_uint(env, payload_size),
+                    enif_make_uint(env, payload_offset),
+                    am_eof));
+    }
+
+    if(bytes_read < payload.size && !enif_realloc_binary(&payload, bytes_read)) {
+        ERTS_INTERNAL_ERROR("Failed to shrink ipread payload.");
+    }
+
+    return enif_make_tuple2(env, am_ok,
+        enif_make_tuple3(env,
+            enif_make_uint(env, payload_size),
+            enif_make_uint(env, payload_offset),
+            enif_make_binary(env, &payload)));
+}
+
+static ERL_NIF_TERM get_handle_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    if(argc != 0) {
+        return enif_make_badarg(env);
+    }
+
+    return efile_get_handle(env, d);
+}
+
+static ERL_NIF_TERM read_info_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_fileinfo_t info = {0};
+    efile_path_t path;
+    int follow_links;
+
+    if(argc != 2 || !enif_get_int(env, argv[1], &follow_links)) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_read_info(&path, follow_links, &info))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    /* #file_info as declared in file.hrl */
+    return enif_make_tuple(env, 14,
+        am_file_info,
+        enif_make_uint64(env, info.size),
+        efile_filetype_to_atom(info.type),
+        efile_access_to_atom(info.access),
+        enif_make_int64(env, MAX(EFILE_MIN_FILETIME, info.a_time)),
+        enif_make_int64(env, MAX(EFILE_MIN_FILETIME, info.m_time)),
+        enif_make_int64(env, MAX(EFILE_MIN_FILETIME, info.c_time)),
+        enif_make_uint(env, info.mode),
+        enif_make_uint(env, info.links),
+        enif_make_uint(env, info.major_device),
+        enif_make_uint(env, info.minor_device),
+        enif_make_uint(env, info.inode),
+        enif_make_uint(env, info.uid),
+        enif_make_uint(env, info.gid)
+    );
+}
+
+static ERL_NIF_TERM set_permissions_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_path_t path;
+    Uint32 permissions;
+
+    if(argc != 2 || !enif_get_uint(env, argv[1], &permissions)) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_set_permissions(&path, permissions))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM set_owner_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_path_t path;
+    Uint32 uid, gid;
+
+    if(argc != 3 || !enif_get_uint(env, argv[1], &uid)
+                 || !enif_get_uint(env, argv[2], &gid)) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_set_owner(&path, uid, gid))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM set_time_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    Sint64 accessed, modified, created;
+    efile_path_t path;
+
+    if(argc != 4 || !enif_get_int64(env, argv[1], &accessed)
+                 || !enif_get_int64(env, argv[2], &modified)
+                 || !enif_get_int64(env, argv[3], &created)) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_set_time(&path, accessed, modified, created))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM read_link_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_path_t path;
+    ERL_NIF_TERM result;
+
+    if(argc != 1) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_read_link(env, &path, &result))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return enif_make_tuple2(env, am_ok, result);
+}
+
+static ERL_NIF_TERM list_dir_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_path_t path;
+    ERL_NIF_TERM result;
+
+    if(argc != 1) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_list_dir(env, &path, &result))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return enif_make_tuple2(env, am_ok, result);
+}
+
+static ERL_NIF_TERM rename_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_path_t existing_path, new_path;
+
+    if(argc != 2) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &existing_path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_marshal_path(env, argv[1], &new_path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_rename(&existing_path, &new_path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM make_hard_link_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_path_t existing_path, new_path;
+
+    if(argc != 2) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &existing_path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_marshal_path(env, argv[1], &new_path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_make_hard_link(&existing_path, &new_path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM make_soft_link_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_path_t existing_path, new_path;
+
+    if(argc != 2) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &existing_path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_marshal_path(env, argv[1], &new_path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_make_soft_link(&existing_path, &new_path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM make_dir_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_path_t path;
+
+    if(argc != 1) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_make_dir(&path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM del_file_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_path_t path;
+
+    if(argc != 1) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_del_file(&path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM del_dir_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_path_t path;
+
+    if(argc != 1) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_del_dir(&path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return am_ok;
+}
+
+static ERL_NIF_TERM get_device_cwd_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    ERL_NIF_TERM result;
+    int device_index;
+
+    if(argc != 1 || !enif_get_int(env, argv[0], &device_index)) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_get_device_cwd(env, device_index, &result))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return enif_make_tuple2(env, am_ok, result);
+}
+
+static ERL_NIF_TERM get_cwd_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+    ERL_NIF_TERM result;
+
+    if(argc != 0) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_get_cwd(env, &result))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return enif_make_tuple2(env, am_ok, result);
+}
+
+static ERL_NIF_TERM set_cwd_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_path_t path;
+
+    if(argc != 1) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_set_cwd(&path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return am_ok;
+}
+
+/** @brief Reads an entire file into \c result, stopping after \c size bytes or
+ * EOF. It will read until EOF if size is 0. */
+static posix_errno_t read_file(efile_data_t *d, size_t size, ErlNifBinary *result) {
+    size_t initial_buffer_size;
+    ssize_t bytes_read;
+
+    if(size == 0) {
+        initial_buffer_size = 16 << 10;
+    } else {
+        initial_buffer_size = size;
+    }
+
+    if(!enif_alloc_binary(initial_buffer_size, result)) {
+        return ENOMEM;
+    }
+
+    bytes_read = 0;
+
+    for(;;) {
+        ssize_t block_bytes_read;
+        SysIOVec read_vec[1];
+
+        read_vec[0].iov_base = result->data + bytes_read;
+        read_vec[0].iov_len = result->size - bytes_read;
+
+        block_bytes_read = efile_readv(d, read_vec, 1);
+
+        if(block_bytes_read < 0) {
+            enif_release_binary(result);
+            return d->posix_errno;
+        }
+
+        bytes_read += block_bytes_read;
+
+        if(block_bytes_read < (result->size - bytes_read)) {
+            /* EOF */
+            break;
+        } else if(bytes_read == size) {
+            break;
+        }
+
+        if(!enif_realloc_binary(result, bytes_read * 2)) {
+            enif_release_binary(result);
+            return ENOMEM;
+        }
+    }
+
+    /* The file may have shrunk since we queried its size, so we have to do
+     * this even when the size is known. */
+    if(bytes_read < result->size && !enif_realloc_binary(result, bytes_read)) {
+        ERTS_INTERNAL_ERROR("Failed to shrink read_file result.");
+    }
+
+    return 0;
+}
+
+static ERL_NIF_TERM read_file_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_fileinfo_t info = {0};
+    efile_path_t path;
+    efile_data_t *d;
+
+    ErlNifBinary result;
+
+    if(argc != 1) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_read_info(&path, 1, &info))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_open(&path, EFILE_MODE_READ, efile_resource_type, &d))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    posix_errno = read_file(d, info.size, &result);
+    enif_release_resource(d);
+
+    if(posix_errno) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return enif_make_tuple2(env, am_ok, enif_make_binary(env, &result));
+}
+
+static ERL_NIF_TERM altname_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    posix_errno_t posix_errno;
+
+    efile_path_t path;
+    ERL_NIF_TERM result;
+
+    if(argc != 1) {
+        return enif_make_badarg(env);
+    }
+
+    if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+        return posix_error_to_tuple(env, posix_errno);
+    } else if((posix_errno = efile_altname(env, &path, &result))) {
+        return posix_error_to_tuple(env, posix_errno);
+    }
+
+    return enif_make_tuple2(env, am_ok, result);
+}
diff --git a/erts/emulator/nifs/common/prim_file_nif.h b/erts/emulator/nifs/common/prim_file_nif.h
new file mode 100644
index 0000000000..cc9bc8f5c3
--- /dev/null
+++ b/erts/emulator/nifs/common/prim_file_nif.h
@@ -0,0 +1,240 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson 2017. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+typedef int posix_errno_t;
+
+enum efile_modes_t {
+    EFILE_MODE_READ = (1 << 0),
+    EFILE_MODE_WRITE = (1 << 1), /* Implies truncating file when used alone. */
+    EFILE_MODE_APPEND = (1 << 2),
+    EFILE_MODE_EXCLUSIVE = (1 << 3),
+    EFILE_MODE_SYNC = (1 << 4),
+
+    EFILE_MODE_SKIP_TYPE_CHECK = (1 << 5), /* Special for device files on Unix. */
+    EFILE_MODE_NO_TRUNCATE = (1 << 6), /* Special for reopening on VxWorks. */
+
+    EFILE_MODE_READ_WRITE = EFILE_MODE_READ | EFILE_MODE_WRITE
+};
+
+enum efile_access_t {
+    EFILE_ACCESS_NONE = 0,
+    EFILE_ACCESS_READ = 1,
+    EFILE_ACCESS_WRITE = 2,
+    EFILE_ACCESS_READ_WRITE = EFILE_ACCESS_READ | EFILE_ACCESS_WRITE
+};
+
+enum efile_seek_t {
+    EFILE_SEEK_BOF,
+    EFILE_SEEK_CUR,
+    EFILE_SEEK_EOF
+};
+
+enum efile_filetype_t {
+    EFILE_FILETYPE_DEVICE,
+    EFILE_FILETYPE_DIRECTORY,
+    EFILE_FILETYPE_REGULAR,
+    EFILE_FILETYPE_SYMLINK,
+    EFILE_FILETYPE_OTHER
+};
+
+enum efile_advise_t {
+    EFILE_ADVISE_NORMAL,
+    EFILE_ADVISE_RANDOM,
+    EFILE_ADVISE_SEQUENTIAL,
+    EFILE_ADVISE_WILL_NEED,
+    EFILE_ADVISE_DONT_NEED,
+    EFILE_ADVISE_NO_REUSE
+};
+
+enum efile_state_t {
+    EFILE_STATE_IDLE = 0,
+    EFILE_STATE_BUSY = 1,
+    EFILE_STATE_CLOSE_PENDING = 2,
+    EFILE_STATE_CLOSED = 3
+};
+
+typedef struct {
+    Sint64 size;            /* Size of file */
+    Uint32 type;            /* Type of file -- one of EFILE_FILETYPE_*. */
+    Uint32 access;          /* Access to file -- one of EFILE_ACCESS_*. */
+    Uint32 mode;            /* Access permissions -- bit field. */
+    Uint32 links;           /* Number of links to file. */
+    Uint32 major_device;    /* Major device or file system. */
+    Uint32 minor_device;    /* Minor device (for devices). */
+    Uint32 inode;           /* Inode number. */
+    Uint32 uid;             /* User id of owner. */
+    Uint32 gid;             /* Group id of owner. */
+    Sint64 a_time;          /* Last time the file was accessed. */
+    Sint64 m_time;          /* Last time the file was modified. */
+    Sint64 c_time;          /* Windows: creation time, Unix: last inode
+                             * change. */
+} efile_fileinfo_t;
+
+/* The smallest value that can be converted freely between universal, local,
+ * and POSIX time, as required by read_file_info/2. Corresponds to
+ * {{1902,1,1},{0,0,0}} */
+#define EFILE_MIN_FILETIME -2145916800
+
+/* Initializes an efile_data_t; must be used in efile_open on success. */
+#define EFILE_INIT_RESOURCE(__d, __modes) do { \
+        erts_atomic32_init_acqb(&(__d)->state, EFILE_STATE_IDLE); \
+        (__d)->posix_errno = 0; \
+        (__d)->modes = __modes; \
+    } while(0)
+
+typedef struct {
+    erts_atomic32_t state;
+
+    posix_errno_t posix_errno;
+    enum efile_modes_t modes;
+
+    ErlNifMonitor monitor;
+} efile_data_t;
+
+typedef ErlNifBinary efile_path_t;
+
+/* @brief Translates the given "raw name" into the format expected by the APIs
+ * used by the underlying implementation. The result is transient and does not
+ * need to be released.
+ *
+ * This may change the structure of the path and its results should never be
+ * passed on to the user. Refer to the OS-specific implementation for details.
+ *
+ * @param path The term to translate; it must have been encoded with
+ * prim_file:internal_native2name for compatibility reasons. */
+posix_errno_t efile_marshal_path(ErlNifEnv *env, ERL_NIF_TERM path, efile_path_t *result);
+
+/* @brief Returns the underlying handle as an implementation-defined term.
+ *
+ * This is an internal function intended to support tests and tricky
+ * operations like sendfile(2). */
+ERL_NIF_TERM efile_get_handle(ErlNifEnv *env, efile_data_t *d);
+
+/* @brief Read until EOF or the given iovec has been filled.
+ *
+ * @return -1 on failure, or the number of bytes read on success. The return
+ * value will be 0 if no bytes could be read before EOF or the end of the
+ * iovec. */
+Sint64 efile_readv(efile_data_t *d, SysIOVec *iov, int iovlen);
+
+/* @brief Write the entirety of the given iovec.
+ *
+ * @return -1 on failure, or the number of bytes written on success. "Partial"
+ * failures will be reported with -1 and not the number of bytes we managed to
+ * write to disk before the failure. */
+Sint64 efile_writev(efile_data_t *d, SysIOVec *iov, int iovlen);
+
+/* @brief As \c efile_readv, but starting from a file offset. */
+Sint64 efile_preadv(efile_data_t *d, Sint64 offset, SysIOVec *iov, int iovlen);
+
+/* @brief As \c efile_writev, but starting from a file offset. */
+Sint64 efile_pwritev(efile_data_t *d, Sint64 offset, SysIOVec *iov, int iovlen);
+
+int efile_seek(efile_data_t *d, enum efile_seek_t seek, Sint64 offset, Sint64 *new_position);
+
+int efile_sync(efile_data_t *d, int data_only);
+
+int efile_advise(efile_data_t *d, Sint64 offset, Sint64 length, enum efile_advise_t advise);
+int efile_allocate(efile_data_t *d, Sint64 offset, Sint64 length);
+int efile_truncate(efile_data_t *d);
+
+posix_errno_t efile_open(const efile_path_t *path, enum efile_modes_t modes,
+        ErlNifResourceType *nif_type, efile_data_t **d);
+
+/** @brief Closes a file. The file must have entered the CLOSED state prior to
+ * calling this to prevent double close. */
+int efile_close(efile_data_t *d);
+
+/* **** **** **** **** **** **** **** **** **** **** **** **** **** **** **** */
+
+posix_errno_t efile_read_info(const efile_path_t *path, int follow_link, efile_fileinfo_t *result);
+
+/** @brief Sets the file times to the given values. Refer to efile_fileinfo_t
+ * for a description of each. */
+posix_errno_t efile_set_time(const efile_path_t *path, Sint64 a_time, Sint64 m_time, Sint64 c_time);
+
+/** @brief On Unix, this sets the file permissions according to the docs for
+ * file:write_file_info/2. On Windows it uses the "owner write permission" flag
+ * to toggle whether the file is read-only or not. */
+posix_errno_t efile_set_permissions(const efile_path_t *path, Uint32 permissions);
+
+/** @brief On Unix, this will set the owner/group to the given values. It will
+ * do nothing on other platforms. */
+posix_errno_t efile_set_owner(const efile_path_t *path, Uint32 owner, Uint32 group);
+
+/** @brief Resolves the final path of the given link. */
+posix_errno_t efile_read_link(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result);
+
+/** @brief Lists the contents of the given directory.
+ * @param result [out] A list of all the directory/file names contained in the
+ * given directory. */
+posix_errno_t efile_list_dir(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result);
+
+/** @brief Changes the name of an existing file or directory, from old_path
+ * to new_path.
+ *
+ * If old_path and new_path refer to the same file or directory, it does
+ * nothing and returns success. Otherwise if new_path already exists, it will
+ * be deleted and replaced by src subject to the following conditions:
+ *
+ *     If old_path is a directory, new_path may be an empty directory.
+ *     If old_path is a file, new_path may be a file.
+ *
+ * Neither of these are guaranteed to be atomic. In any other situation where
+ * new_path already exists, the rename will fail.
+ *
+ * Some possible error codes:
+ *
+ * - EACCES:     Either paths or one of their parent directories can't be read
+ *               and/or written.
+ * - EEXIST:     new_path is a non-empty directory.
+ * - EINVAL:     old_path is a root directory or new_path is a subdirectory
+ *               of new_path.
+ * - EISDIR:     new_path is a directory, but old_path is not.
+ * - ENOTDIR:    old_path is a directory, but new_path is not.
+ * - ENOENT:     old_path doesn't exist, or either path is "".
+ * - EXDEV:      The paths are on different filesystems.
+ *
+ * The implementation of rename may allow cross-filesystem renames,
+ * but the caller should be prepared to emulate it with copy and
+ * delete if errno is EXDEV. */
+posix_errno_t efile_rename(const efile_path_t *old_path, const efile_path_t *new_path);
+
+posix_errno_t efile_make_hard_link(const efile_path_t *existing_path, const efile_path_t *new_path);
+posix_errno_t efile_make_soft_link(const efile_path_t *existing_path, const efile_path_t *new_path);
+posix_errno_t efile_make_dir(const efile_path_t *path);
+
+posix_errno_t efile_del_file(const efile_path_t *path);
+posix_errno_t efile_del_dir(const efile_path_t *path);
+
+posix_errno_t efile_get_cwd(ErlNifEnv *env, ERL_NIF_TERM *result);
+posix_errno_t efile_set_cwd(const efile_path_t *path);
+
+/** @brief A Windows-specific function for returning the working directory of a
+ * given device.
+ *
+ * @param device_index The drive index; 1 for A, 2 for B, etc.
+ * @param result [out] The working directory of the given device
+ */
+posix_errno_t efile_get_device_cwd(ErlNifEnv *env, int device_index, ERL_NIF_TERM *result);
+
+/** @brief A Windows-specific function for returning the 8.3-name of a given
+ * file or directory. */
+posix_errno_t efile_altname(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result);
diff --git a/erts/emulator/nifs/unix/unix_prim_file.c b/erts/emulator/nifs/unix/unix_prim_file.c
new file mode 100644
index 0000000000..57c8ef62e1
--- /dev/null
+++ b/erts/emulator/nifs/unix/unix_prim_file.c
@@ -0,0 +1,957 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson 2017. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+#include "erl_nif.h"
+#include "config.h"
+#include "sys.h"
+
+#ifdef VALGRIND
+#  include <valgrind/memcheck.h>
+#endif
+
+#include "prim_file_nif.h"
+
+#if defined(__APPLE__) && defined(__MACH__) && !defined(__DARWIN__)
+#define __DARWIN__ 1
+#endif
+
+#if defined(__DARWIN__) || defined(HAVE_LINUX_FALLOC_H) || defined(HAVE_POSIX_FALLOCATE)
+#include <fcntl.h>
+#endif
+
+#ifdef HAVE_LINUX_FALLOC_H
+#include <linux/falloc.h>
+#endif
+
+#include <utime.h>
+
+/* Macros for testing file types. */
+#ifdef NO_UMASK
+#define FILE_MODE 0644
+#define DIR_MODE  0755
+#else
+#define FILE_MODE 0666
+#define DIR_MODE  0777
+#endif
+
+/* Old platforms might not have IOV_MAX defined. */
+#if !defined(IOV_MAX) && defined(UIO_MAXIOV)
+#define IOV_MAX UIO_MAXIOV
+#elif !defined(IOV_MAX)
+#define IOV_MAX 16
+#endif
+
+typedef struct {
+    efile_data_t common;
+    int fd;
+} efile_unix_t;
+
+static int has_invalid_null_termination(const ErlNifBinary *path) {
+    const char *null_pos, *end_pos;
+
+    null_pos = memchr(path->data, '\0', path->size);
+    end_pos = (const char*)&path->data[path->size] - 1;
+
+    if(null_pos == NULL) {
+        return 1;
+    }
+
+    /* prim_file:internal_name2native sometimes feeds us data that is "doubly"
+     * NUL-terminated, so we'll accept any number of trailing NULs so long as
+     * they aren't interrupted by anything else. */
+    while(null_pos < end_pos && (*null_pos) == '\0') {
+        null_pos++;
+    }
+
+    return null_pos != end_pos;
+}
+
+posix_errno_t efile_marshal_path(ErlNifEnv *env, ERL_NIF_TERM path, efile_path_t *result) {
+    if(!enif_inspect_binary(env, path, result)) {
+        return EINVAL;
+    }
+
+    if(has_invalid_null_termination(result)) {
+        return EINVAL;
+    }
+
+    return 0;
+}
+
+ERL_NIF_TERM efile_get_handle(ErlNifEnv *env, efile_data_t *d) {
+    efile_unix_t *u = (efile_unix_t*)d;
+
+    ERL_NIF_TERM result;
+    unsigned char *bits;
+
+    bits = enif_make_new_binary(env, sizeof(u->fd), &result);
+    memcpy(bits, &u->fd, sizeof(u->fd));
+
+    return result;
+}
+
+static int open_file_type_check(const efile_path_t *path, int fd) {
+    struct stat file_info;
+    int error;
+
+#ifndef HAVE_FSTAT
+    error = stat((const char*)path->data, &file_info);
+    (void)fd;
+#else
+    error = fstat(fd, &file_info);
+    (void)path;
+#endif
+
+    if(error < 0) {
+        /* If we failed to stat assume success and let the next call handle the
+         * error. The old driver checked whether the file was to be used
+         * immediately in a read within the call, but the new implementation
+         * never does that. */
+         return 1;
+    } else {
+        /* The old driver tolerated opening /dev/null despite the "no devices"
+         * limitation. It provided no explanation for this but we still need
+         * to match the behavior. We're checking through stat(2) instead of
+         * comparing the name to account for links. */
+        struct stat null_device_info;
+        int is_dev_null;
+
+        is_dev_null = (stat("/dev/null", &null_device_info) == 0);
+        is_dev_null &= (file_info.st_ino == null_device_info.st_ino);
+        is_dev_null &= (file_info.st_dev == null_device_info.st_dev);
+
+        if(is_dev_null) {
+            return 1;
+        }
+    }
+
+    if(!S_ISREG(file_info.st_mode)) {
+        return 0;
+    }
+
+    return 1;
+}
+
+posix_errno_t efile_open(const efile_path_t *path, enum efile_modes_t modes,
+        ErlNifResourceType *nif_type, efile_data_t **d) {
+
+    int flags, fd;
+
+    flags = 0;
+
+    if(modes & EFILE_MODE_READ && !(modes & EFILE_MODE_WRITE)) {
+        flags |= O_RDONLY;
+    } else if(modes & EFILE_MODE_WRITE && !(modes & EFILE_MODE_READ)) {
+        if(!(modes & EFILE_MODE_NO_TRUNCATE)) {
+            flags |= O_TRUNC;
+        }
+
+        flags |= O_WRONLY | O_CREAT;
+    } else if(modes & EFILE_MODE_READ_WRITE) {
+        flags |= O_RDWR | O_CREAT;
+    } else {
+        return EINVAL;
+    }
+
+    if(modes & EFILE_MODE_APPEND) {
+        flags &= ~O_TRUNC;
+        flags |= O_APPEND;
+    }
+
+    if(modes & EFILE_MODE_EXCLUSIVE) {
+        flags |= O_EXCL;
+    }
+
+    if(modes & EFILE_MODE_SYNC) {
+#ifndef O_SYNC
+        return ENOTSUP;
+#else
+        flags |= O_SYNC;
+#endif
+    }
+
+    do {
+        fd = open((const char*)path->data, flags, FILE_MODE);
+    } while(fd == -1 && errno == EINTR);
+
+    if(fd != -1) {
+        efile_unix_t *u;
+
+        if(!(modes & EFILE_MODE_SKIP_TYPE_CHECK) && !open_file_type_check(path, fd)) {
+            close(fd);
+
+            /* This is blatantly incorrect, but we're documented as returning
+             * this for everything that isn't a file. */
+            return EISDIR;
+        }
+
+        u = (efile_unix_t*)enif_alloc_resource(nif_type, sizeof(efile_unix_t));
+        u->fd = fd;
+
+        EFILE_INIT_RESOURCE(&u->common, modes);
+        (*d) = &u->common;
+
+        return 0;
+    }
+
+    (*d) = NULL;
+    return errno;
+}
+
+int efile_close(efile_data_t *d) {
+    efile_unix_t *u = (efile_unix_t*)d;
+    int fd;
+
+    ASSERT(erts_atomic32_read_nob(&d->state) == EFILE_STATE_CLOSED);
+    ASSERT(u->fd != -1);
+
+    fd = u->fd;
+    u->fd = -1;
+
+    /* close(2) either always closes (*BSD, Linux) or leaves the fd in an
+     * undefined state (POSIX 2008, Solaris), so we must not retry on EINTR. */
+
+    if(close(fd) < 0) {
+        u->common.posix_errno = errno;
+        return 0;
+    }
+
+    return 1;
+}
+
+static void shift_iov(SysIOVec **iov, int *iovlen, ssize_t shift) {
+    SysIOVec *head_vec = (*iov);
+
+    ASSERT(shift >= 0);
+
+    while(shift > 0) {
+        ASSERT(head_vec < &(*iov)[*iovlen]);
+
+        if(shift < head_vec->iov_len) {
+            head_vec->iov_base = (char*)head_vec->iov_base + shift;
+            head_vec->iov_len -= shift;
+            break;
+        } else {
+            shift -= head_vec->iov_len;
+            head_vec++;
+        }
+    }
+
+    (*iovlen) -= head_vec - (*iov);
+    (*iov) = head_vec;
+}
+
+Sint64 efile_readv(efile_data_t *d, SysIOVec *iov, int iovlen) {
+    efile_unix_t *u = (efile_unix_t*)d;
+
+    Sint64 bytes_read;
+    ssize_t result;
+
+    bytes_read = 0;
+
+    do {
+        int use_fallback = 0;
+
+        if(iovlen < 1) {
+            result = 0;
+            break;
+        }
+
+        /* writev(2) implies readv(2) */
+#ifdef HAVE_WRITEV
+        result = readv(u->fd, iov, MIN(IOV_MAX, iovlen));
+
+        /* Fall back to using read(2) if readv(2) reports that the combined
+         * size of iov is greater than SSIZE_T_MAX. */
+        use_fallback = (result < 0 && errno == EINVAL);
+#else
+        use_fallback = 1;
+#endif
+
+        if(use_fallback) {
+            result = read(u->fd, iov->iov_base, iov->iov_len);
+        }
+
+        if(result > 0) {
+            shift_iov(&iov, &iovlen, result);
+            bytes_read += result;
+        }
+    } while(result > 0 || (result < 0 && errno == EINTR));
+
+    u->common.posix_errno = errno;
+
+    if(result == 0 && bytes_read > 0) {
+        return bytes_read;
+    }
+
+    return result;
+}
+
+Sint64 efile_writev(efile_data_t *d, SysIOVec *iov, int iovlen) {
+    efile_unix_t *u = (efile_unix_t*)d;
+
+    Sint64 bytes_written;
+    ssize_t result;
+
+    bytes_written = 0;
+
+    do {
+        int use_fallback = 0;
+
+        if(iovlen < 1) {
+            result = 0;
+            break;
+        }
+
+#ifdef HAVE_WRITEV
+        result = writev(u->fd, iov, MIN(IOV_MAX, iovlen));
+
+        /* Fall back to using write(2) if writev(2) reports that the combined
+         * size of iov is greater than SSIZE_T_MAX. */
+        use_fallback = (result < 0 && errno == EINVAL);
+#else
+        use_fallback = 1;
+#endif
+
+        if(use_fallback) {
+            result = write(u->fd, iov->iov_base, iov->iov_len);
+        }
+
+        if(result > 0) {
+            shift_iov(&iov, &iovlen, result);
+            bytes_written += result;
+        }
+    } while(result > 0 || (result < 0 && errno == EINTR));
+
+    u->common.posix_errno = errno;
+
+    if(result == 0 && bytes_written > 0) {
+        return bytes_written;
+    }
+
+    return result;
+}
+
+Sint64 efile_preadv(efile_data_t *d, Sint64 offset, SysIOVec *iov, int iovlen) {
+    efile_unix_t *u = (efile_unix_t*)d;
+
+    Uint64 bytes_read;
+    Sint64 result;
+
+#if !defined(HAVE_PREADV) && !defined(HAVE_PREAD)
+    /* This function is documented as leaving the file position undefined, but
+     * the old driver always reset it so there's probably code in the wild that
+     * relies on this behavior. */
+    off_t original_position = lseek(u->fd, 0, SEEK_CUR);
+
+    if(original_position < 0 || lseek(u->fd, offset, SEEK_SET) < 0) {
+        u->common.posix_errno = errno;
+        return -1;
+    }
+#endif
+
+    bytes_read = 0;
+
+    do {
+        if(iovlen < 1) {
+            result = 0;
+            break;
+        }
+
+#if defined(HAVE_PREADV)
+        result = preadv(u->fd, iov, MIN(IOV_MAX, iovlen), offset);
+#elif defined(HAVE_PREAD)
+        result = pread(u->fd, iov->iov_base, iov->iov_len, offset);
+#else
+        result = read(u->fd, iov->iov_base, iov->iov_len);
+#endif
+
+        if(result > 0) {
+            shift_iov(&iov, &iovlen, result);
+            bytes_read += result;
+            offset += result;
+        }
+    } while(result > 0 || (result < 0 && errno == EINTR));
+
+    u->common.posix_errno = errno;
+
+#if !defined(HAVE_PREADV) && !defined(HAVE_PREAD)
+    if(result >= 0) {
+        if(lseek(u->fd, original_position, SEEK_SET) < 0) {
+            u->common.posix_errno = errno;
+            return -1;
+        }
+    }
+#endif
+
+    if(result == 0 && bytes_read > 0) {
+        return bytes_read;
+    }
+
+    return result;
+}
+
+Sint64 efile_pwritev(efile_data_t *d, Sint64 offset, SysIOVec *iov, int iovlen) {
+    efile_unix_t *u = (efile_unix_t*)d;
+
+    Sint64 bytes_written;
+    ssize_t result;
+
+#if !defined(HAVE_PWRITEV) && !defined(HAVE_PWRITE)
+    off_t original_position = lseek(u->fd, 0, SEEK_CUR);
+
+    if(original_position < 0 || lseek(u->fd, offset, SEEK_SET) < 0) {
+        u->common.posix_errno = errno;
+        return -1;
+    }
+#endif
+
+    bytes_written = 0;
+
+    do {
+        if(iovlen < 1) {
+            result = 0;
+            break;
+        }
+
+#if defined(HAVE_PWRITEV)
+        result = pwritev(u->fd, iov, MIN(IOV_MAX, iovlen), offset);
+#elif defined(HAVE_PWRITE)
+        result = pwrite(u->fd, iov->iov_base, iov->iov_len, offset);
+#else
+        result = write(u->fd, iov->iov_base, iov->iov_len);
+#endif
+
+        if(result > 0) {
+            shift_iov(&iov, &iovlen, result);
+            bytes_written += result;
+            offset += result;
+        }
+    } while(result > 0 || (result < 0 && errno == EINTR));
+
+    u->common.posix_errno = errno;
+
+#if !defined(HAVE_PWRITEV) && !defined(HAVE_PWRITE)
+    if(result >= 0) {
+        if(lseek(u->fd, original_position, SEEK_SET) < 0) {
+            u->common.posix_errno = errno;
+            return -1;
+        }
+    }
+#endif
+
+    if(result == 0 && bytes_written > 0) {
+        return bytes_written;
+    }
+
+    return result;
+}
+
+int efile_seek(efile_data_t *d, enum efile_seek_t seek, Sint64 offset, Sint64 *new_position) {
+    efile_unix_t *u = (efile_unix_t*)d;
+    off_t result;
+    int whence;
+
+    switch(seek) {
+        case EFILE_SEEK_BOF: whence = SEEK_SET; break;
+        case EFILE_SEEK_CUR: whence = SEEK_CUR; break;
+        case EFILE_SEEK_EOF: whence = SEEK_END; break;
+        default: ERTS_INTERNAL_ERROR("Invalid seek parameter");
+    }
+
+    result = lseek(u->fd, offset, whence);
+
+    /*
+     * The man page for lseek (on SunOs 5) says:
+     *
+     * "if fildes is a remote file descriptor and offset is negative, lseek()
+     * returns the file pointer even if it is negative."
+     */
+    if(result < 0 && errno == 0) {
+        errno = EINVAL;
+    }
+
+    if(result < 0) {
+        u->common.posix_errno = errno;
+        return 0;
+    }
+
+    (*new_position) = result;
+
+    return 1;
+}
+
+int efile_sync(efile_data_t *d, int data_only) {
+    efile_unix_t *u = (efile_unix_t*)d;
+
+#if defined(HAVE_FDATASYNC) && !defined(__DARWIN__)
+    if(data_only) {
+        if(fdatasync(u->fd) < 0) {
+            u->common.posix_errno = errno;
+            return 0;
+        }
+
+        return 1;
+    }
+#endif
+
+#if defined(__DARWIN__) && defined(F_FULLFSYNC)
+    if(fcntl(u->fd, F_FULLFSYNC) < 0) {
+#else
+    if(fsync(u->fd) < 0) {
+#endif
+        u->common.posix_errno = errno;
+        return 0;
+    }
+
+    return 1;
+}
+
+int efile_advise(efile_data_t *d, Sint64 offset, Sint64 length, enum efile_advise_t advise) {
+    efile_unix_t *u = (efile_unix_t*)d;
+#ifdef HAVE_POSIX_FADVISE
+    int p_advise;
+
+    switch(advise) {
+        case EFILE_ADVISE_NORMAL: p_advise = POSIX_FADV_NORMAL; break;
+        case EFILE_ADVISE_RANDOM: p_advise = POSIX_FADV_RANDOM; break;
+        case EFILE_ADVISE_SEQUENTIAL: p_advise = POSIX_FADV_SEQUENTIAL; break;
+        case EFILE_ADVISE_WILL_NEED: p_advise = POSIX_FADV_WILLNEED; break;
+        case EFILE_ADVISE_DONT_NEED: p_advise = POSIX_FADV_DONTNEED; break;
+        case EFILE_ADVISE_NO_REUSE: p_advise = POSIX_FADV_NOREUSE; break;
+        default:
+            u->common.posix_errno = EINVAL;
+            return 0;
+    }
+
+    if(posix_fadvise(u->fd, offset, length, p_advise) < 0) {
+        u->common.posix_errno = errno;
+        return 0;
+    }
+
+    return 1;
+#else
+    /* We'll pretend to support this syscall as it's only a recommendation even
+     * on systems that do support it. */
+    return 1;
+#endif
+}
+
+int efile_allocate(efile_data_t *d, Sint64 offset, Sint64 length) {
+    efile_unix_t *u = (efile_unix_t*)d;
+    int ret = -1;
+
+    /* We prefer OS-specific methods, but fall back to posix_fallocate on
+     * failure. It's unclear whether this has any practical benefit on
+     * modern systems, but the old driver did it. */
+
+#if defined(HAVE_FALLOCATE)
+    /* Linux-specific */
+    do {
+        ret = fallocate(u->fd, FALLOC_FL_KEEP_SIZE, offset, length);
+    } while(ret < 0 && errno == EINTR);
+#elif defined(F_PREALLOCATE)
+    /* Mac-specific */
+    fstore_t fs = {};
+
+    fs.fst_flags = F_ALLOCATECONTIG;
+    fs.fst_posmode = F_VOLPOSMODE;
+    fs.fst_offset = offset;
+    fs.fst_length = length;
+
+    ret = fcntl(u->fd, F_PREALLOCATE, &fs);
+    if(ret < 0) {
+        fs.fst_flags = F_ALLOCATEALL;
+        ret = fcntl(u->fd, F_PREALLOCATE, &fs);
+    }
+#elif !defined(HAVE_POSIX_FALLOCATE)
+    u->common.posix_errno = ENOTSUP;
+    return 0;
+#endif
+
+#ifdef HAVE_POSIX_FALLOCATE
+    if(ret < 0) {
+        do {
+            ret = posix_fallocate(u->fd, offset, length);
+
+            /* On Linux and Solaris for example, posix_fallocate() returns a
+             * positive error number on error and it does not set errno. On
+             * FreeBSD however (9.0 at least), it returns -1 on error and it
+             * sets errno. */
+            if (ret > 0) {
+                errno = ret;
+                ret = -1;
+            }
+        } while(ret < 0 && errno == EINTR);
+    }
+#endif
+
+    if(ret < 0) {
+        u->common.posix_errno = errno;
+        return 0;
+    }
+
+    return 1;
+}
+
+int efile_truncate(efile_data_t *d) {
+    efile_unix_t *u = (efile_unix_t*)d;
+    off_t offset;
+
+    offset = lseek(u->fd, 0, SEEK_CUR);
+
+    if(offset < 0) {
+        u->common.posix_errno = errno;
+        return 0;
+    }
+
+    if(ftruncate(u->fd, offset) < 0) {
+        u->common.posix_errno = errno;
+        return 0;
+    }
+
+    return 1;
+}
+
+posix_errno_t efile_read_info(const efile_path_t *path, int follow_links, efile_fileinfo_t *result) {
+    struct stat data;
+
+    if(follow_links) {
+        if(stat((const char*)path->data, &data) < 0) {
+            return errno;
+        }
+    } else {
+        if(lstat((const char*)path->data, &data) < 0) {
+            return errno;
+        }
+    }
+
+    if(S_ISCHR(data.st_mode) || S_ISBLK(data.st_mode)) {
+        result->type = EFILE_FILETYPE_DEVICE;
+    } else if(S_ISDIR(data.st_mode)) {
+        result->type = EFILE_FILETYPE_DIRECTORY;
+    } else if(S_ISREG(data.st_mode)) {
+        result->type = EFILE_FILETYPE_REGULAR;
+    } else if(S_ISLNK(data.st_mode)) {
+        result->type = EFILE_FILETYPE_SYMLINK;
+    } else {
+        result->type = EFILE_FILETYPE_OTHER;
+    }
+
+    result->a_time = (Sint64)data.st_atime;
+    result->m_time = (Sint64)data.st_mtime;
+    result->c_time = (Sint64)data.st_ctime;
+    result->size = data.st_size;
+
+    result->major_device = data.st_dev;
+    result->minor_device = data.st_rdev;
+    result->links = data.st_nlink;
+    result->inode = data.st_ino;
+    result->mode = data.st_mode;
+    result->uid = data.st_uid;
+    result->gid = data.st_gid;
+
+#ifndef NO_ACCESS
+    result->access = EFILE_ACCESS_NONE;
+
+    if(access((const char*)path->data, R_OK) == 0) {
+        result->access |= EFILE_ACCESS_READ;
+    }
+    if(access((const char*)path->data, W_OK) == 0) {
+        result->access |= EFILE_ACCESS_WRITE;
+    }
+#else
+    /* Just look at read/write access for owner. */
+    result->access = ((data.st_mode >> 6) & 07) >> 1;
+#endif
+
+    return 0;
+}
+
+posix_errno_t efile_set_permissions(const efile_path_t *path, Uint32 permissions) {
+    const mode_t MUTABLE_MODES = (S_ISUID | S_ISGID | S_IRWXU | S_IRWXG | S_IRWXO);
+    mode_t new_modes = permissions & MUTABLE_MODES;
+
+    if(chmod((const char*)path->data, new_modes) < 0) {
+        new_modes &= ~(S_ISUID | S_ISGID);
+
+        if (chmod((const char*)path->data, new_modes) < 0) {
+            return errno;
+        }
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_set_owner(const efile_path_t *path, Uint32 owner, Uint32 group) {
+    if(chown((const char*)path->data, owner, group) < 0) {
+        return errno;
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_set_time(const efile_path_t *path, Sint64 a_time, Sint64 m_time, Sint64 c_time) {
+    struct utimbuf tval;
+
+    tval.actime = (time_t)a_time;
+    tval.modtime = (time_t)m_time;
+
+    (void)c_time;
+
+    if(utime((const char*)path->data, &tval) < 0) {
+        return errno;
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_read_link(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result) {
+    ErlNifBinary result_bin;
+
+    if(!enif_alloc_binary(256, &result_bin)) {
+        return ENOMEM;
+    }
+
+    for(;;) {
+        ssize_t bytes_copied;
+
+        bytes_copied = readlink((const char*)path->data, (char*)result_bin.data,
+            result_bin.size);
+
+        if(bytes_copied <= 0) {
+            posix_errno_t saved_errno = errno;
+            enif_release_binary(&result_bin);
+            return saved_errno;
+        } else if(bytes_copied < result_bin.size) {
+            if(!enif_realloc_binary(&result_bin, bytes_copied)) {
+                enif_release_binary(&result_bin);
+                return ENOMEM;
+            }
+
+            (*result) = enif_make_binary(env, &result_bin);
+
+            return 0;
+        }
+
+        /* The result didn't fit into the buffer, so we'll try again with a
+         * larger one. */
+
+        if(!enif_realloc_binary(&result_bin, result_bin.size * 2)) {
+            enif_release_binary(&result_bin);
+            return ENOMEM;
+        }
+    }
+}
+
+static int is_ignored_name(int name_length, const char *name) {
+    if(name_length == 1 && name[0] == '.') {
+        return 1;
+    } else if(name_length == 2 && memcmp(name, "..", 2) == 0) {
+        return 1;
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_list_dir(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result) {
+    ERL_NIF_TERM list_head;
+
+    struct dirent *dir_entry;
+    DIR *dir_stream;
+
+    dir_stream = opendir((const char*)path->data);
+    if(dir_stream == NULL) {
+        posix_errno_t saved_errno = errno;
+        *result = enif_make_list(env, 0);
+        return saved_errno;
+    }
+
+    list_head = enif_make_list(env, 0);
+    dir_entry = readdir(dir_stream);
+
+    while(dir_entry != NULL) {
+        int name_length = strlen(dir_entry->d_name);
+
+        if(!is_ignored_name(name_length, dir_entry->d_name)) {
+            unsigned char *name_bytes;
+            ERL_NIF_TERM name_term;
+
+            name_bytes = enif_make_new_binary(env, name_length, &name_term);
+            sys_memcpy(name_bytes, dir_entry->d_name, name_length);
+
+            list_head = enif_make_list_cell(env, name_term, list_head);
+        }
+
+        dir_entry = readdir(dir_stream);
+    }
+
+    (*result) = list_head;
+    closedir(dir_stream);
+
+    return 0;
+}
+
+posix_errno_t efile_rename(const efile_path_t *old_path, const efile_path_t *new_path) {
+    if(rename((const char*)old_path->data, (const char*)new_path->data) < 0) {
+        if(errno == ENOTEMPTY) {
+            return EEXIST;
+        }
+
+        if(strcmp((const char*)old_path->data, "/") == 0) {
+            /* Alpha reports renaming / as EBUSY and Linux reports it as EACCES
+             * instead of EINVAL.*/
+             return EINVAL;
+        }
+
+        return errno;
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_make_hard_link(const efile_path_t *existing_path, const efile_path_t *new_path) {
+    if(link((const char*)existing_path->data, (const char*)new_path->data) < 0) {
+        return errno;
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_make_soft_link(const efile_path_t *existing_path, const efile_path_t *new_path) {
+    if(symlink((const char*)existing_path->data, (const char*)new_path->data) < 0) {
+        return errno;
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_make_dir(const efile_path_t *path) {
+#ifdef NO_MKDIR_MODE
+    if(mkdir((const char*)path->data) < 0) {
+#else
+    if(mkdir((const char*)path->data, DIR_MODE) < 0) {
+#endif
+        return errno;
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_del_file(const efile_path_t *path) {
+    if(unlink((const char*)path->data) < 0) {
+        /* Linux sets the wrong error code. */
+        if(errno == EISDIR) {
+            return EPERM;
+        }
+
+        return errno;
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_del_dir(const efile_path_t *path) {
+    if(rmdir((const char*)path->data) < 0) {
+        posix_errno_t saved_errno = errno;
+
+        if(saved_errno == ENOTEMPTY) {
+            saved_errno = EEXIST;
+        }
+
+        /* The error code might be wrong if we're trying to delete the current
+         * directory. */
+        if(saved_errno == EEXIST) {
+            struct stat path_stat, cwd_stat;
+            int has_stat;
+
+            has_stat = (stat((const char*)path->data, &path_stat) == 0);
+            has_stat &= (stat(".", &cwd_stat) == 0);
+
+            if(has_stat && path_stat.st_ino == cwd_stat.st_ino) {
+                if(path_stat.st_dev == cwd_stat.st_dev) {
+                    return EINVAL;
+                }
+            }
+        }
+
+        return saved_errno;
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_set_cwd(const efile_path_t *path) {
+    if(chdir((const char*)path->data) < 0) {
+        return errno;
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_get_device_cwd(ErlNifEnv *env, int device_index, ERL_NIF_TERM *result) {
+    (void)device_index;
+    (void)result;
+    (void)env;
+
+    return ENOTSUP;
+}
+
+posix_errno_t efile_get_cwd(ErlNifEnv *env, ERL_NIF_TERM *result) {
+    ErlNifBinary result_bin;
+    size_t bytes_copied;
+
+    if(!enif_alloc_binary(256, &result_bin)) {
+        return ENOMEM;
+    }
+
+    while(getcwd((char*)result_bin.data, result_bin.size) == NULL) {
+        posix_errno_t saved_errno = errno;
+
+        if(saved_errno != ERANGE) {
+            enif_release_binary(&result_bin);
+            return saved_errno;
+        } else {
+            if(!enif_realloc_binary(&result_bin, result_bin.size * 2)) {
+                enif_release_binary(&result_bin);
+                return ENOMEM;
+            }
+        }
+    }
+
+    /* getcwd(2) guarantees null-termination. */
+    bytes_copied = strlen((const char*)result_bin.data);
+
+    if(!enif_realloc_binary(&result_bin, bytes_copied)) {
+        enif_release_binary(&result_bin);
+        return ENOMEM;
+    }
+
+    (*result) = enif_make_binary(env, &result_bin);
+
+    return 0;
+}
+
+posix_errno_t efile_altname(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result) {
+    (void)path;
+    (void)result;
+
+    return ENOTSUP;
+}
diff --git a/erts/emulator/nifs/win32/win_prim_file.c b/erts/emulator/nifs/win32/win_prim_file.c
new file mode 100644
index 0000000000..9b79182f2c
--- /dev/null
+++ b/erts/emulator/nifs/win32/win_prim_file.c
@@ -0,0 +1,1428 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson 2017. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+#include "erl_nif.h"
+#include "config.h"
+#include "sys.h"
+
+#include "prim_file_nif.h"
+
+#include <windows.h>
+#include <strsafe.h>
+#include <wchar.h>
+
+#define IS_SLASH(a)  ((a) == L'\\' || (a) == L'/')
+
+#define FILE_SHARE_FLAGS (FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE)
+
+#define LP_PREFIX L"\\\\?\\"
+#define LP_PREFIX_SIZE (sizeof(LP_PREFIX) - sizeof(WCHAR))
+#define LP_PREFIX_LENGTH (LP_PREFIX_SIZE / sizeof(WCHAR))
+
+#define PATH_LENGTH(path) (path->size / sizeof(WCHAR) - 1)
+
+#define ASSERT_PATH_FORMAT(path) \
+    do { \
+        ASSERT(PATH_LENGTH(path) >= 4 && \
+            !memcmp(path->data, LP_PREFIX, LP_PREFIX_SIZE)); \
+        ASSERT(PATH_LENGTH(path) == wcslen((WCHAR*)path->data)); \
+    } while(0)
+
+#define TICKS_PER_SECOND (10000000ULL)
+#define EPOCH_DIFFERENCE (11644473600LL)
+
+#define FILETIME_TO_EPOCH(epoch, ft) \
+    do { \
+        ULARGE_INTEGER ull; \
+        ull.LowPart  = (ft).dwLowDateTime; \
+        ull.HighPart = (ft).dwHighDateTime; \
+        (epoch) = ((ull.QuadPart / TICKS_PER_SECOND) - EPOCH_DIFFERENCE); \
+    } while(0)
+
+#define EPOCH_TO_FILETIME(ft, epoch) \
+    do { \
+        ULARGE_INTEGER ull; \
+        ull.QuadPart = (((epoch) + EPOCH_DIFFERENCE) * TICKS_PER_SECOND); \
+        (ft).dwLowDateTime = ull.LowPart; \
+        (ft).dwHighDateTime = ull.HighPart; \
+    } while(0)
+
+typedef struct {
+    efile_data_t common;
+    HANDLE handle;
+} efile_win_t;
+
+static int windows_to_posix_errno(DWORD last_error);
+
+static int has_invalid_null_termination(const ErlNifBinary *path) {
+    const WCHAR *null_pos, *end_pos;
+
+    null_pos = wmemchr((const WCHAR*)path->data, L'\0', path->size);
+    end_pos = (const WCHAR*)&path->data[path->size] - 1;
+
+    if(null_pos == NULL) {
+        return 1;
+    }
+
+    /* prim_file:internal_name2native sometimes feeds us data that is "doubly"
+     * NUL-terminated, so we'll accept any number of trailing NULs so long as
+     * they aren't interrupted by anything else. */
+    while(null_pos < end_pos && (*null_pos) == L'\0') {
+        null_pos++;
+    }
+
+    return null_pos != end_pos;
+}
+
+static posix_errno_t get_full_path(ErlNifEnv *env, WCHAR *input, efile_path_t *result) {
+    DWORD maximum_length, actual_length;
+    int add_long_prefix;
+
+    maximum_length = GetFullPathNameW(input, 0, NULL, NULL);
+    add_long_prefix = 0;
+
+    if(maximum_length == 0) {
+        /* POSIX doesn't have the concept of a "path error" in the same way
+         * Windows does, so we'll return ENOENT since that's what most POSIX
+         * APIs would return if they were fed such garbage. */
+        return ENOENT;
+    }
+
+    maximum_length += LP_PREFIX_LENGTH;
+
+    if(!enif_alloc_binary(maximum_length * sizeof(WCHAR), result)) {
+        return ENOMEM;
+    }
+
+    actual_length = GetFullPathNameW(input, maximum_length, (WCHAR*)result->data, NULL);
+
+    if(actual_length < maximum_length) {
+        int has_long_path_prefix;
+        WCHAR *path_start;
+
+        /* Make sure we have a long-path prefix; GetFullPathNameW only adds one
+         * if the path is relative. */
+        has_long_path_prefix = actual_length >= LP_PREFIX_LENGTH &&
+            !sys_memcmp(result->data, LP_PREFIX, LP_PREFIX_SIZE);
+
+        if(!has_long_path_prefix) {
+            sys_memmove(result->data + LP_PREFIX_SIZE, result->data,
+                (actual_length + 1) * sizeof(WCHAR));
+            sys_memcpy(result->data, LP_PREFIX, LP_PREFIX_SIZE);
+            actual_length += LP_PREFIX_LENGTH;
+        }
+
+        path_start = (WCHAR*)result->data;
+
+        /* We're removing trailing slashes since quite a few APIs refuse to
+         * work with them, and none require them. We only check the last
+         * character since GetFullPathNameW folds slashes together. */
+        if(IS_SLASH(path_start[actual_length - 1])) {
+            if(path_start[actual_length - 2] != L':') {
+                path_start[actual_length - 1] = L'\0';
+                actual_length--;
+            }
+        }
+
+        if(!enif_realloc_binary(result, (actual_length + 1) * sizeof(WCHAR))) {
+            enif_release_binary(result);
+            return ENOMEM;
+        }
+
+        enif_make_binary(env, result);
+        return 0;
+    }
+
+    /* We may end up here if the current directory changes to something longer
+     * between/during GetFullPathName. There's nothing sensible we can do about
+     * this. */
+
+    enif_release_binary(result);
+
+    return EINVAL;
+}
+
+posix_errno_t efile_marshal_path(ErlNifEnv *env, ERL_NIF_TERM path, efile_path_t *result) {
+    ErlNifBinary raw_path;
+
+    if(!enif_inspect_binary(env, path, &raw_path)) {
+        return EINVAL;
+    } else if(raw_path.size % sizeof(WCHAR)) {
+        return EINVAL;
+    }
+
+    if(has_invalid_null_termination(&raw_path)) {
+        return EINVAL;
+    }
+
+    return get_full_path(env, (WCHAR*)raw_path.data, result);
+}
+
+ERL_NIF_TERM efile_get_handle(ErlNifEnv *env, efile_data_t *d) {
+    efile_win_t *w = (efile_win_t*)d;
+
+    ERL_NIF_TERM result;
+    unsigned char *bits;
+
+    bits = enif_make_new_binary(env, sizeof(w->handle), &result);
+    memcpy(bits, &w->handle, sizeof(w->handle));
+
+    return result;
+}
+
+/** @brief Converts a native path to the preferred form in "erlang space,"
+ * without path-prefixes, forward-slashes, or NUL terminators. */
+static int normalize_path_result(ErlNifBinary *path) {
+    WCHAR *path_iterator, *path_start, *path_end;
+    int length;
+
+    path_start = (WCHAR*)path->data;
+    length = wcslen(path_start);
+
+    ASSERT(length < path->size / sizeof(WCHAR));
+
+    /* Get rid of the long-path prefix, if present. */
+    if(length >= LP_PREFIX_LENGTH) {
+        if(!sys_memcmp(path_start, LP_PREFIX, LP_PREFIX_SIZE)) {
+            length -= LP_PREFIX_LENGTH;
+
+            sys_memmove(path_start, &path_start[LP_PREFIX_LENGTH],
+                length * sizeof(WCHAR));
+        }
+    }
+
+    path_end = &path_start[length];
+    path_iterator = path_start;
+
+    /* Convert drive letters to lowercase, if present. */
+    if(length >= 2 && path_start[1] == L':') {
+        WCHAR drive_letter = path_start[0];
+
+        if(drive_letter >= L'A' && drive_letter <= L'Z') {
+            path_start[0] = drive_letter - L'A' + L'a';
+        }
+    }
+
+    while(path_iterator < path_end) {
+        if(*path_iterator == L'\\') {
+            *path_iterator = L'/';
+        }
+
+        path_iterator++;
+    }
+
+    /* Truncate the result to its actual length; we don't want to include the
+     * NUL terminator. */
+    return enif_realloc_binary(path, length * sizeof(WCHAR));
+}
+
+/* @brief Checks whether all the given attributes are set on the object at the
+ * given path. Note that it assumes false on errors. */
+static int has_file_attributes(const efile_path_t *path, DWORD mask) {
+    DWORD attributes = GetFileAttributesW((WCHAR*)path->data);
+
+    if(attributes == INVALID_FILE_ATTRIBUTES) {
+        return 0;
+    }
+
+    return !!((attributes & mask) == mask);
+}
+
+static int is_ignored_name(int name_length, const WCHAR *name) {
+    if(name_length == 1 && name[0] == L'.') {
+        return 1;
+    } else if(name_length == 2 && !sys_memcmp(name, L"..", 2 * sizeof(WCHAR))) {
+        return 1;
+    }
+
+    return 0;
+}
+
+static int get_drive_number(const efile_path_t *path) {
+    const WCHAR *path_start;
+    int length;
+
+    ASSERT_PATH_FORMAT(path);
+
+    path_start = (WCHAR*)path->data + LP_PREFIX_LENGTH;
+    length = PATH_LENGTH(path) - LP_PREFIX_LENGTH;
+
+    if(length >= 2 && path_start[1] == L':') {
+        WCHAR drive_letter = path_start[0];
+
+        if(drive_letter >= L'A' && drive_letter <= L'Z') {
+            return drive_letter - L'A' + 1;
+        } else if(drive_letter >= L'a' && drive_letter <= L'z') {
+            return drive_letter - L'a' + 1;
+        }
+    }
+
+    return -1;
+}
+
+/* @brief Checks whether two *paths* are on the same mount point; they don't
+ * have to refer to existing or accessible files/directories. */
+static int has_same_mount_point(const efile_path_t *path_a, const efile_path_t *path_b) {
+    WCHAR *mount_a, *mount_b;
+    int result = 0;
+
+    mount_a = enif_alloc(path_a->size);
+    mount_b = enif_alloc(path_b->size);
+
+    if(mount_a != NULL && mount_b != NULL) {
+        int length_a, length_b;
+
+        length_a = PATH_LENGTH(path_a);
+        length_b = PATH_LENGTH(path_b);
+
+        if(GetVolumePathNameW((WCHAR*)path_a->data, mount_a, length_a)) {
+            ASSERT(wcslen(mount_a) <= length_a);
+
+            if(GetVolumePathNameW((WCHAR*)path_b->data, mount_b, length_b)) {
+                ASSERT(wcslen(mount_b) <= length_b);
+
+                result = !_wcsicmp(mount_a, mount_b);
+            }
+        }
+    }
+
+    if(mount_b != NULL) {
+        enif_free(mount_b);
+    }
+
+    if(mount_a != NULL) {
+        enif_free(mount_a);
+    }
+
+    return result;
+}
+
+/* Mirrors the PathIsRootW function of the shell API, but doesn't choke on
+ * paths longer than MAX_PATH. */
+static int is_path_root(const efile_path_t *path) {
+    const WCHAR *path_start, *path_end;
+    int length;
+
+    ASSERT_PATH_FORMAT(path);
+
+    path_start = (WCHAR*)path->data + LP_PREFIX_LENGTH;
+    length = PATH_LENGTH(path) - LP_PREFIX_LENGTH;
+
+    path_end = &path_start[length];
+
+    if(length == 1) {
+        /* A single \ refers to the root of the current working directory. */
+        return IS_SLASH(path_start[0]);
+    } else if(length == 3 && iswalpha(path_start[0]) && path_start[1] == L':') {
+        /* Drive letter. */
+        return IS_SLASH(path_start[2]);
+    } else if(length >= 4) {
+        /* Check whether we're a UNC root, eg. \\server, \\server\share */
+        const WCHAR *path_iterator;
+
+        if(!IS_SLASH(path_start[0]) || !IS_SLASH(path_start[1])) {
+            return 0;
+        }
+
+        path_iterator = path_start + 2;
+
+        /* Slide to the slash between the server and share names, if present. */
+        while(path_iterator < path_end && !IS_SLASH(*path_iterator)) {
+            path_iterator++;
+        }
+
+        /* Slide past the end of the string, stopping at the first slash we
+         * encounter. */
+        do {
+            path_iterator++;
+        }  while(path_iterator < path_end && !IS_SLASH(*path_iterator));
+
+        /* If we're past the end of the string and it didnt't end with a slash,
+         * then we're a root path. */
+        return path_iterator >= path_end && !IS_SLASH(path_start[length - 1]);
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_open(const efile_path_t *path, enum efile_modes_t modes,
+        ErlNifResourceType *nif_type, efile_data_t **d) {
+
+    DWORD attributes, access_flags, open_mode;
+    HANDLE handle;
+
+    ASSERT_PATH_FORMAT(path);
+
+    access_flags = 0;
+    open_mode = 0;
+
+    if(modes & EFILE_MODE_READ && !(modes & EFILE_MODE_WRITE)) {
+        access_flags = GENERIC_READ;
+        open_mode = OPEN_EXISTING;
+    } else if(modes & EFILE_MODE_WRITE && !(modes & EFILE_MODE_READ)) {
+        access_flags = GENERIC_WRITE;
+        open_mode = CREATE_ALWAYS;
+    } else if(modes & EFILE_MODE_READ_WRITE) {
+        access_flags = GENERIC_READ | GENERIC_WRITE;
+        open_mode = OPEN_ALWAYS;
+    } else {
+        return EINVAL;
+    }
+
+    if(modes & EFILE_MODE_APPEND) {
+        access_flags |= FILE_APPEND_DATA;
+        open_mode = OPEN_ALWAYS;
+    }
+
+    if(modes & EFILE_MODE_EXCLUSIVE) {
+        open_mode = CREATE_NEW;
+    }
+
+    if(modes & EFILE_MODE_SYNC) {
+        attributes = FILE_FLAG_WRITE_THROUGH;
+    } else {
+        attributes = FILE_ATTRIBUTE_NORMAL;
+    }
+
+    handle = CreateFileW((WCHAR*)path->data, access_flags,
+        FILE_SHARE_FLAGS, NULL, open_mode, attributes, NULL);
+
+    if(handle != INVALID_HANDLE_VALUE) {
+        efile_win_t *w;
+
+        w = (efile_win_t*)enif_alloc_resource(nif_type, sizeof(efile_win_t));
+        w->handle = handle;
+
+        EFILE_INIT_RESOURCE(&w->common, modes);
+        (*d) = &w->common;
+
+        return 0;
+    } else {
+        DWORD last_error = GetLastError();
+
+        /* Rewrite all failures on directories to EISDIR to match the old
+         * driver. */
+        if(has_file_attributes(path, FILE_ATTRIBUTE_DIRECTORY)) {
+            return EISDIR;
+        }
+
+        return windows_to_posix_errno(last_error);
+    }
+}
+
+int efile_close(efile_data_t *d) {
+    efile_win_t *w = (efile_win_t*)d;
+    HANDLE handle;
+
+    ASSERT(erts_atomic32_read_nob(&d->state) == EFILE_STATE_CLOSED);
+    ASSERT(w->handle != INVALID_HANDLE_VALUE);
+
+    handle = w->handle;
+    w->handle = INVALID_HANDLE_VALUE;
+
+    if(!CloseHandle(handle)) {
+        w->common.posix_errno = windows_to_posix_errno(GetLastError());
+        return 0;
+    }
+
+    return 1;
+}
+
+static void shift_overlapped(OVERLAPPED *overlapped, DWORD shift) {
+    LARGE_INTEGER offset;
+
+    ASSERT(shift >= 0);
+
+    offset.HighPart = overlapped->OffsetHigh;
+    offset.LowPart = overlapped->Offset;
+
+    /* ~(Uint64)0 is a magic value ("append to end of file") which needs to be
+     * preserved. Other positions resulting in overflow would have errored out
+     * just prior to this point. */
+    if(offset.QuadPart != ERTS_UINT64_MAX) {
+        offset.QuadPart += shift;
+    }
+
+    /* All unused fields must be zeroed for the next call. */
+    sys_memset(overlapped, 0, sizeof(*overlapped));
+    overlapped->OffsetHigh = offset.HighPart;
+    overlapped->Offset = offset.LowPart;
+}
+
+static void shift_iov(SysIOVec **iov, int *iovlen, DWORD shift) {
+    SysIOVec *head_vec = (*iov);
+
+    ASSERT(shift >= 0);
+
+    while(shift > 0) {
+        ASSERT(head_vec < &(*iov)[*iovlen]);
+
+        if(shift < head_vec->iov_len) {
+            head_vec->iov_base = (char*)head_vec->iov_base + shift;
+            head_vec->iov_len -= shift;
+            break;
+        } else {
+            shift -= head_vec->iov_len;
+            head_vec++;
+        }
+    }
+
+    (*iovlen) -= head_vec - (*iov);
+    (*iov) = head_vec;
+}
+
+typedef BOOL (WINAPI *io_op_t)(HANDLE, LPVOID, DWORD, LPDWORD, LPOVERLAPPED);
+
+static Sint64 internal_sync_io(efile_win_t *w, io_op_t operation,
+        SysIOVec *iov, int iovlen, OVERLAPPED *overlapped) {
+
+    Sint64 bytes_processed = 0;
+
+    for(;;) {
+        DWORD block_bytes_processed, last_error;
+        BOOL succeeded;
+
+        if(iovlen < 1) {
+            return bytes_processed;
+        }
+
+        succeeded = operation(w->handle, iov->iov_base, iov->iov_len,
+            &block_bytes_processed, overlapped);
+        last_error = GetLastError();
+
+        if(!succeeded && (last_error != ERROR_HANDLE_EOF)) {
+            w->common.posix_errno = windows_to_posix_errno(last_error);
+            return -1;
+        } else if(block_bytes_processed == 0) {
+            /* EOF */
+            return bytes_processed;
+        }
+
+        if(overlapped != NULL) {
+            shift_overlapped(overlapped, block_bytes_processed);
+        }
+
+        shift_iov(&iov, &iovlen, block_bytes_processed);
+
+        bytes_processed += block_bytes_processed;
+    }
+}
+
+Sint64 efile_readv(efile_data_t *d, SysIOVec *iov, int iovlen) {
+    efile_win_t *w = (efile_win_t*)d;
+
+    return internal_sync_io(w, ReadFile, iov, iovlen, NULL);
+}
+
+Sint64 efile_writev(efile_data_t *d, SysIOVec *iov, int iovlen) {
+    efile_win_t *w = (efile_win_t*)d;
+
+    OVERLAPPED __overlapped, *overlapped;
+    Uint64 bytes_written;
+
+    if(w->common.modes & EFILE_MODE_APPEND) {
+        overlapped = &__overlapped;
+
+        sys_memset(overlapped, 0, sizeof(*overlapped));
+        overlapped->OffsetHigh = 0xFFFFFFFF;
+        overlapped->Offset = 0xFFFFFFFF;
+    } else {
+        overlapped = NULL;
+    }
+
+    return internal_sync_io(w, WriteFile, iov, iovlen, overlapped);
+}
+
+Sint64 efile_preadv(efile_data_t *d, Sint64 offset, SysIOVec *iov, int iovlen) {
+    efile_win_t *w = (efile_win_t*)d;
+
+    OVERLAPPED overlapped;
+
+    sys_memset(&overlapped, 0, sizeof(overlapped));
+    overlapped.OffsetHigh = (offset >> 32) & 0xFFFFFFFF;
+    overlapped.Offset = offset & 0xFFFFFFFF;
+
+    return internal_sync_io(w, ReadFile, iov, iovlen, &overlapped);
+}
+
+Sint64 efile_pwritev(efile_data_t *d, Sint64 offset, SysIOVec *iov, int iovlen) {
+    efile_win_t *w = (efile_win_t*)d;
+
+    OVERLAPPED overlapped;
+
+    sys_memset(&overlapped, 0, sizeof(overlapped));
+    overlapped.OffsetHigh = (offset >> 32) & 0xFFFFFFFF;
+    overlapped.Offset = offset & 0xFFFFFFFF;
+
+    return internal_sync_io(w, WriteFile, iov, iovlen, &overlapped);
+}
+
+int efile_seek(efile_data_t *d, enum efile_seek_t seek, Sint64 offset, Sint64 *new_position) {
+    efile_win_t *w = (efile_win_t*)d;
+
+    LARGE_INTEGER large_offset, large_new_position;
+    DWORD whence;
+
+    switch(seek) {
+        case EFILE_SEEK_BOF: whence = FILE_BEGIN; break;
+        case EFILE_SEEK_CUR: whence = FILE_CURRENT; break;
+        case EFILE_SEEK_EOF: whence = FILE_END; break;
+        default: ERTS_INTERNAL_ERROR("Invalid seek parameter");
+    }
+
+    large_offset.QuadPart = offset;
+
+    if(!SetFilePointerEx(w->handle, large_offset, &large_new_position, whence)) {
+        w->common.posix_errno = windows_to_posix_errno(GetLastError());
+        return 0;
+    }
+
+    (*new_position) = large_new_position.QuadPart;
+
+    return 1;
+}
+
+int efile_sync(efile_data_t *d, int data_only) {
+    efile_win_t *w = (efile_win_t*)d;
+
+    /* Windows doesn't support data-only syncing. */
+    (void)data_only;
+
+    if(!FlushFileBuffers(w->handle)) {
+        w->common.posix_errno = windows_to_posix_errno(GetLastError());
+        return 0;
+    }
+
+    return 1;
+}
+
+int efile_advise(efile_data_t *d, Sint64 offset, Sint64 length, enum efile_advise_t advise) {
+    /* Windows doesn't support this, but we'll pretend it does since the call
+     * is only a recommendation even on systems that do support it. */
+
+    (void)d;
+    (void)offset;
+    (void)length;
+    (void)advise;
+
+    return 1;
+}
+
+int efile_allocate(efile_data_t *d, Sint64 offset, Sint64 length) {
+    efile_win_t *w = (efile_win_t*)d;
+
+    (void)d;
+    (void)offset;
+    (void)length;
+
+    w->common.posix_errno = ENOTSUP;
+
+    return 0;
+}
+
+int efile_truncate(efile_data_t *d) {
+    efile_win_t *w = (efile_win_t*)d;
+
+    if(!SetEndOfFile(w->handle)) {
+        w->common.posix_errno = windows_to_posix_errno(GetLastError());
+        return 0;
+    }
+
+    return 1;
+}
+
+static int is_executable_file(const efile_path_t *path) {
+    /* We're using the file extension in order to be quirks-compliant with the
+     * old driver, which never bothered to check the actual permissions. We
+     * could easily do so now (cf. GetNamedSecurityInfo) but the execute
+     * permission is only relevant for files that are started with the default
+     * loader, and batch files run just fine with read permission alone. */
+
+    int length = PATH_LENGTH(path);
+
+    if(length >= 4) {
+        const WCHAR *last_four = &((WCHAR*)path->data)[length - 4];
+
+        if (!_wcsicmp(last_four, L".exe") ||
+            !_wcsicmp(last_four, L".cmd") ||
+            !_wcsicmp(last_four, L".bat") ||
+            !_wcsicmp(last_four, L".com")) {
+            return 1;
+        }
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_read_info(const efile_path_t *path, int follow_links, efile_fileinfo_t *result) {
+    BY_HANDLE_FILE_INFORMATION native_file_info;
+    DWORD attributes;
+
+    sys_memset(&native_file_info, 0, sizeof(native_file_info));
+
+    attributes = GetFileAttributesW((WCHAR*)path->data);
+
+    if(attributes == INVALID_FILE_ATTRIBUTES) {
+        DWORD last_error = GetLastError();
+
+        /* Querying a network share root fails with ERROR_BAD_NETPATH, so we'll
+         * fake it as a directory just like local roots. */
+        if(!is_path_root(path) || last_error != ERROR_BAD_NETPATH) {
+            return windows_to_posix_errno(last_error);
+        }
+
+        attributes = FILE_ATTRIBUTE_DIRECTORY;
+    } else if(is_path_root(path)) {
+        /* Local (or mounted) roots can be queried with GetFileAttributesW but
+         * lack support for GetFileInformationByHandle, so we'll skip that
+         * part. */
+    } else {
+        HANDLE handle;
+
+        if(follow_links && (attributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
+            posix_errno_t posix_errno;
+            efile_path_t resolved_path;
+
+            posix_errno = internal_read_link(path, &resolved_path);
+
+            if(posix_errno != 0) {
+                return posix_errno;
+            }
+
+            return efile_read_info(&resolved_path, 0, result);
+        }
+
+        handle = CreateFileW((const WCHAR*)path->data, GENERIC_READ,
+            FILE_SHARE_FLAGS, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS,
+            NULL);
+
+        /* The old driver never cared whether this succeeded. */
+        if(handle != INVALID_HANDLE_VALUE) {
+            GetFileInformationByHandle(handle, &native_file_info);
+            CloseHandle(handle);
+        }
+
+        FILETIME_TO_EPOCH(result->m_time, native_file_info.ftLastWriteTime);
+        FILETIME_TO_EPOCH(result->a_time, native_file_info.ftLastAccessTime);
+        FILETIME_TO_EPOCH(result->c_time, native_file_info.ftCreationTime);
+
+        if(result->m_time == -EPOCH_DIFFERENCE) {
+            /* Default to 1970 just like the old driver. */
+            result->m_time = 0;
+        }
+
+        if(result->a_time == -EPOCH_DIFFERENCE) {
+            result->a_time = result->m_time;
+        }
+
+        if(result->c_time == -EPOCH_DIFFERENCE) {
+            result->c_time = result->m_time;
+        }
+    }
+
+    if(attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
+        result->type = EFILE_FILETYPE_SYMLINK;
+        /* This should be _S_IFLNK, but the old driver always set
+         * non-directories to _S_IFREG. */
+        result->mode |= _S_IFREG;
+    } else if(attributes & FILE_ATTRIBUTE_DIRECTORY) {
+        result->type = EFILE_FILETYPE_DIRECTORY;
+        result->mode |= _S_IFDIR | _S_IEXEC;
+    } else {
+        if(is_executable_file(path)) {
+            result->mode |= _S_IEXEC;
+        }
+
+        result->type = EFILE_FILETYPE_REGULAR;
+        result->mode |= _S_IFREG;
+    }
+
+    if(!(attributes & FILE_ATTRIBUTE_READONLY)) {
+        result->access = EFILE_ACCESS_READ | EFILE_ACCESS_WRITE;
+        result->mode |= _S_IREAD | _S_IWRITE;
+    } else {
+        result->access = EFILE_ACCESS_READ;
+        result->mode |= _S_IREAD;
+    }
+
+    /* Propagate user mode-bits to group/other fields */
+    result->mode |= (result->mode & 0700) >> 3;
+    result->mode |= (result->mode & 0700) >> 6;
+
+    result->size =
+        ((Uint64)native_file_info.nFileSizeHigh << 32ull) |
+        (Uint64)native_file_info.nFileSizeLow;
+
+    result->links = MAX(1, native_file_info.nNumberOfLinks);
+
+    result->major_device = get_drive_number(path);
+    result->minor_device = 0;
+    result->inode = 0;
+    result->uid = 0;
+    result->gid = 0;
+
+    return 0;
+}
+
+posix_errno_t efile_set_permissions(const efile_path_t *path, Uint32 permissions) {
+    DWORD attributes = GetFileAttributesW((WCHAR*)path->data);
+
+    if(attributes == INVALID_FILE_ATTRIBUTES) {
+        return windows_to_posix_errno(GetLastError());
+    }
+
+    if(permissions & _S_IWRITE) {
+        attributes &= ~FILE_ATTRIBUTE_READONLY;
+    } else {
+        attributes |= FILE_ATTRIBUTE_READONLY;
+    }
+
+    if(SetFileAttributesW((WCHAR*)path->data, attributes)) {
+        return 0;
+    }
+
+    return windows_to_posix_errno(GetLastError());
+}
+
+posix_errno_t efile_set_owner(const efile_path_t *path, Uint32 owner, Uint32 group) {
+    (void)path;
+    (void)owner;
+    (void)group;
+
+    return 0;
+}
+
+posix_errno_t efile_set_time(const efile_path_t *path, Sint64 a_time, Sint64 m_time, Sint64 c_time) {
+    FILETIME accessed, modified, created;
+    DWORD last_error, attributes;
+    HANDLE handle;
+
+    attributes = GetFileAttributesW((WCHAR*)path->data);
+
+    if(attributes == INVALID_FILE_ATTRIBUTES) {
+        return windows_to_posix_errno(GetLastError());
+    }
+
+    /* If the file is read-only, we have to make it temporarily writable while
+     * setting new metadata. */
+    if(attributes & FILE_ATTRIBUTE_READONLY) {
+        DWORD without_readonly = attributes & ~FILE_ATTRIBUTE_READONLY;
+
+        if(!SetFileAttributesW((WCHAR*)path->data, without_readonly)) {
+            return windows_to_posix_errno(GetLastError());
+        }
+    }
+
+    EPOCH_TO_FILETIME(modified, m_time);
+    EPOCH_TO_FILETIME(accessed, a_time);
+    EPOCH_TO_FILETIME(created, c_time);
+
+    handle = CreateFileW((WCHAR*)path->data, GENERIC_READ | GENERIC_WRITE,
+        FILE_SHARE_FLAGS, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+    last_error = GetLastError();
+
+    if(handle != INVALID_HANDLE_VALUE) {
+        if(SetFileTime(handle, &created, &accessed, &modified)) {
+            last_error = ERROR_SUCCESS;
+        } else {
+            last_error = GetLastError();
+        }
+
+        CloseHandle(handle);
+    }
+
+    if(attributes & FILE_ATTRIBUTE_READONLY) {
+        SetFileAttributesW((WCHAR*)path->data, attributes);
+    }
+
+    return windows_to_posix_errno(last_error);
+}
+
+static posix_errno_t internal_read_link(const efile_path_t *path, efile_path_t *result) {
+    DWORD required_length, actual_length;
+    HANDLE link_handle;
+    DWORD last_error;
+
+    link_handle = CreateFileW((WCHAR*)path->data, GENERIC_READ,
+        FILE_SHARE_FLAGS, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+    last_error = GetLastError();
+
+    if(link_handle == INVALID_HANDLE_VALUE) {
+        return windows_to_posix_errno(last_error);
+    }
+
+    required_length = GetFinalPathNameByHandleW(link_handle, NULL, 0, 0);
+    last_error = GetLastError();
+
+    if(required_length <= 0) {
+        CloseHandle(link_handle);
+        return windows_to_posix_errno(last_error);
+    }
+
+    /* Unlike many other path functions (eg. GetFullPathNameW), this one
+     * includes the NUL terminator in its required length. */
+    if(!enif_alloc_binary(required_length * sizeof(WCHAR), result)) {
+        CloseHandle(link_handle);
+        return ENOMEM;
+    }
+
+    actual_length = GetFinalPathNameByHandleW(link_handle,
+        (WCHAR*)result->data, required_length, 0);
+    last_error = GetLastError();
+
+    CloseHandle(link_handle);
+
+    if(actual_length == 0 || actual_length >= required_length) {
+        enif_release_binary(result);
+        return windows_to_posix_errno(last_error);
+    }
+
+    /* GetFinalPathNameByHandle always prepends with "\\?\" and NUL-terminates,
+     * so we never have to touch-up the resulting path. */
+
+    ASSERT_PATH_FORMAT(result);
+
+    return 0;
+}
+
+posix_errno_t efile_read_link(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result) {
+    posix_errno_t posix_errno;
+    ErlNifBinary result_bin;
+    DWORD attributes;
+
+    ASSERT_PATH_FORMAT(path);
+
+    attributes = GetFileAttributesW((WCHAR*)path->data);
+
+    if(attributes == INVALID_FILE_ATTRIBUTES) {
+        return windows_to_posix_errno(GetLastError());
+    } else if(!(attributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
+        return EINVAL;
+    }
+
+    posix_errno = internal_read_link(path, &result_bin);
+
+    if(posix_errno == 0) {
+        if(!normalize_path_result(&result_bin)) {
+            enif_release_binary(&result_bin);
+            return ENOMEM;
+        }
+
+        (*result) = enif_make_binary(env, &result_bin);
+    }
+
+    return posix_errno;
+}
+
+posix_errno_t efile_list_dir(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result) {
+    ERL_NIF_TERM list_head;
+    WIN32_FIND_DATAW data;
+    HANDLE search_handle;
+    WCHAR *search_path;
+    DWORD last_error;
+
+    ASSERT_PATH_FORMAT(path);
+
+    search_path = enif_alloc(path->size + 2 * sizeof(WCHAR));
+
+    if(search_path == NULL) {
+        return ENOMEM;
+    }
+
+    sys_memcpy(search_path, path->data, path->size);
+    search_path[PATH_LENGTH(path) + 0] = L'\\';
+    search_path[PATH_LENGTH(path) + 1] = L'*';
+    search_path[PATH_LENGTH(path) + 2] = L'\0';
+
+    search_handle = FindFirstFileW(search_path, &data);
+    last_error = GetLastError();
+
+    enif_free(search_path);
+
+    if(search_handle == INVALID_HANDLE_VALUE) {
+        return windows_to_posix_errno(last_error);
+    }
+
+    list_head = enif_make_list(env, 0);
+
+    do {
+        int name_length = wcslen(data.cFileName);
+
+        if(!is_ignored_name(name_length, data.cFileName)) {
+            unsigned char *name_bytes;
+            ERL_NIF_TERM name_term;
+            size_t name_size;
+
+            name_size = name_length * sizeof(WCHAR);
+
+            name_bytes = enif_make_new_binary(env, name_size, &name_term);
+            sys_memcpy(name_bytes, data.cFileName, name_size);
+
+            list_head = enif_make_list_cell(env, name_term, list_head);
+        }
+    } while(FindNextFileW(search_handle, &data));
+
+    FindClose(search_handle);
+    (*result) = list_head;
+
+    return 0;
+}
+
+posix_errno_t efile_rename(const efile_path_t *old_path, const efile_path_t *new_path) {
+    BOOL old_is_directory, new_is_directory;
+    DWORD move_flags, last_error;
+
+    ASSERT_PATH_FORMAT(old_path);
+    ASSERT_PATH_FORMAT(new_path);
+
+    move_flags = MOVEFILE_COPY_ALLOWED | MOVEFILE_WRITE_THROUGH;
+
+    if(MoveFileExW((WCHAR*)old_path->data, (WCHAR*)new_path->data, move_flags)) {
+        return 0;
+    }
+
+    last_error = GetLastError();
+
+    old_is_directory = has_file_attributes(old_path, FILE_ATTRIBUTE_DIRECTORY);
+    new_is_directory = has_file_attributes(new_path, FILE_ATTRIBUTE_DIRECTORY);
+
+    switch(last_error) {
+    case ERROR_SHARING_VIOLATION:
+    case ERROR_ACCESS_DENIED:
+        if(old_is_directory) {
+            BOOL moved_into_itself;
+
+            moved_into_itself = (old_path->size <= new_path->size) &&
+                !_wcsnicmp((WCHAR*)old_path->data, (WCHAR*)new_path->data,
+                    PATH_LENGTH(old_path));
+
+            if(moved_into_itself) {
+                return EINVAL;
+            } else if(is_path_root(old_path)) {
+                return EINVAL;
+            }
+
+            /* Renaming a directory across volumes needs to be rewritten as
+             * EXDEV so that the caller can respond by simulating it with
+             * copy/delete operations.
+             *
+             * Files are handled through MOVEFILE_COPY_ALLOWED. */
+            if(!has_same_mount_point(old_path, new_path)) {
+                return EXDEV;
+            }
+        }
+        break;
+    case ERROR_PATH_NOT_FOUND:
+    case ERROR_FILE_NOT_FOUND:
+        return ENOENT;
+    case ERROR_ALREADY_EXISTS:
+    case ERROR_FILE_EXISTS:
+        if(old_is_directory && !new_is_directory) {
+            return ENOTDIR;
+        } else if(!old_is_directory && new_is_directory) {
+            return EISDIR;
+        } else if(old_is_directory && new_is_directory) {
+            /* This will fail if the destination isn't empty. */
+            if(RemoveDirectoryW((WCHAR*)new_path->data)) {
+                return efile_rename(old_path, new_path);
+            }
+
+            return EEXIST;
+        } else if(!old_is_directory && !new_is_directory) {
+            /* This is pretty iffy; the public documentation says that the
+             * operation may EACCES on some systems when either file is open,
+             * which gives us room to use MOVEFILE_REPLACE_EXISTING and be done
+             * with it, but the old implementation simulated Unix semantics and
+             * there's a lot of code that relies on that.
+             *
+             * The simulation renames the destination to a scratch name to get
+             * around the fact that it's impossible to open (and by extension
+             * rename) a file that's been deleted while open. It has a few
+             * drawbacks though;
+             *
+             * 1) It's not atomic as there's a small window where there's no
+             *    file at all on the destination path.
+             * 2) It will confuse applications that subscribe to folder
+             *    changes.
+             * 3) It will fail if we lack general permission to write in the
+             *    same folder. */
+
+            WCHAR *swap_path = enif_alloc(new_path->size + sizeof(WCHAR) * 64);
+
+            if(swap_path == NULL) {
+                return ENOMEM;
+            } else {
+                static LONGLONG unique_counter = 0;
+                WCHAR *swap_path_end;
+
+                /* We swap in the same folder as the destination to be
+                 * reasonably sure that it's on the same volume. Note that
+                 * we're avoiding GetTempFileNameW as it will fail on long
+                 * paths. */
+
+                sys_memcpy(swap_path, (WCHAR*)new_path->data, new_path->size);
+                swap_path_end = swap_path + PATH_LENGTH(new_path);
+
+                while(!IS_SLASH(*swap_path_end)) {
+                    ASSERT(swap_path_end > swap_path);
+                    swap_path_end--;
+                }
+
+                StringCchPrintfW(&swap_path_end[1], 64, L"erl-%lx-%llx.tmp",
+                    GetCurrentProcessId(), unique_counter);
+                InterlockedIncrement64(&unique_counter);
+            }
+
+            if(MoveFileExW((WCHAR*)new_path->data, swap_path, MOVEFILE_REPLACE_EXISTING)) {
+                if(MoveFileExW((WCHAR*)old_path->data, (WCHAR*)new_path->data, move_flags)) {
+                    last_error = ERROR_SUCCESS;
+                    DeleteFileW(swap_path);
+                } else {
+                    last_error = GetLastError();
+                    MoveFileW(swap_path, (WCHAR*)new_path->data);
+                }
+            } else {
+                last_error = GetLastError();
+                DeleteFileW(swap_path);
+            }
+
+            enif_free(swap_path);
+
+            return windows_to_posix_errno(last_error);
+        }
+
+        return EEXIST;
+    }
+
+    return windows_to_posix_errno(last_error);
+}
+
+posix_errno_t efile_make_hard_link(const efile_path_t *existing_path, const efile_path_t *new_path) {
+    ASSERT_PATH_FORMAT(existing_path);
+    ASSERT_PATH_FORMAT(new_path);
+
+    if(!CreateHardLinkW((WCHAR*)new_path->data, (WCHAR*)existing_path->data, NULL)) {
+        return windows_to_posix_errno(GetLastError());
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_make_soft_link(const efile_path_t *existing_path, const efile_path_t *new_path) {
+    DWORD link_flags;
+
+    ASSERT_PATH_FORMAT(existing_path);
+    ASSERT_PATH_FORMAT(new_path);
+
+    if(has_file_attributes(existing_path, FILE_ATTRIBUTE_DIRECTORY)) {
+        link_flags = SYMBOLIC_LINK_FLAG_DIRECTORY;
+    } else {
+        link_flags = 0;
+    }
+
+    if(!CreateSymbolicLinkW((WCHAR*)new_path->data, (WCHAR*)existing_path->data, link_flags)) {
+        return windows_to_posix_errno(GetLastError());
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_make_dir(const efile_path_t *path) {
+    ASSERT_PATH_FORMAT(path);
+
+    if(!CreateDirectoryW((WCHAR*)path->data, NULL)) {
+        return windows_to_posix_errno(GetLastError());
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_del_file(const efile_path_t *path) {
+    ASSERT_PATH_FORMAT(path);
+
+    if(!DeleteFileW((WCHAR*)path->data)) {
+        DWORD last_error = GetLastError();
+
+        switch(last_error) {
+        case ERROR_INVALID_NAME:
+            /* Attempted to delete a device or similar. */
+            return EACCES;
+        case ERROR_ACCESS_DENIED:
+            /* Windows NT reports removing a directory as EACCES instead of
+             * EPERM. */
+            if(has_file_attributes(path, FILE_ATTRIBUTE_DIRECTORY)) {
+                return EPERM;
+            }
+            break;
+        }
+
+        return windows_to_posix_errno(last_error);
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_del_dir(const efile_path_t *path) {
+    ASSERT_PATH_FORMAT(path);
+
+    if(!RemoveDirectoryW((WCHAR*)path->data)) {
+        DWORD last_error = GetLastError();
+
+        if(last_error == ERROR_DIRECTORY) {
+            return ENOTDIR;
+        }
+
+        return windows_to_posix_errno(last_error);
+    }
+
+    return 0;
+}
+
+posix_errno_t efile_set_cwd(const efile_path_t *path) {
+    const WCHAR *path_start;
+
+    ASSERT_PATH_FORMAT(path);
+
+    /* We have to use _wchdir since that's the only function that updates the
+     * per-drive working directory, but it naively assumes that all paths
+     * starting with \\ are UNC paths, so we have to skip the \\?\-prefix. */
+    path_start = (WCHAR*)path->data + LP_PREFIX_LENGTH;
+
+    if(_wchdir(path_start)) {
+        return windows_to_posix_errno(GetLastError());
+    }
+
+    return 0;
+}
+
+static int is_valid_drive(int device_index) {
+    WCHAR drive_path[4] = {L'?', L':', L'\\', L'\0'};
+
+    if(device_index == 0) {
+        /* Default drive; always valid. */
+        return 1;
+    } else if(device_index > (L'Z' - L'A' + 1)) {
+        return 0;
+    }
+
+    drive_path[0] = device_index + L'A' - 1;
+
+    switch(GetDriveTypeW(drive_path)) {
+    case DRIVE_NO_ROOT_DIR:
+    case DRIVE_UNKNOWN:
+        return 0;
+    }
+
+    return 1;
+}
+
+posix_errno_t efile_get_device_cwd(ErlNifEnv *env, int device_index, ERL_NIF_TERM *result) {
+    ErlNifBinary result_bin;
+
+    /* _wgetdcwd might crash the entire emulator on debug builds since the CRT
+     * invalid parameter handler asserts if passed a non-existent drive (Or
+     * simply one that has been unmounted), so we check it ourselves to avoid
+     * that. */
+    if(!is_valid_drive(device_index)) {
+        return EACCES;
+    }
+
+    if(!enif_alloc_binary(MAX_PATH * sizeof(WCHAR), &result_bin)) {
+        return ENOMEM;
+    }
+
+    if(_wgetdcwd(device_index, (WCHAR*)result_bin.data, MAX_PATH) == NULL) {
+        enif_release_binary(&result_bin);
+        return EACCES;
+    }
+
+    if(!normalize_path_result(&result_bin)) {
+        enif_release_binary(&result_bin);
+        return ENOMEM;
+    }
+
+    (*result) = enif_make_binary(env, &result_bin);
+
+    return 0;
+}
+
+posix_errno_t efile_get_cwd(ErlNifEnv *env, ERL_NIF_TERM *result) {
+    return efile_get_device_cwd(env, 0, result);
+}
+
+posix_errno_t efile_altname(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result) {
+    ErlNifBinary result_bin;
+
+    ASSERT_PATH_FORMAT(path);
+
+    if(is_path_root(path)) {
+        /* Root paths can't be queried so we'll just return them as they are. */
+        if(!enif_alloc_binary(path->size, &result_bin)) {
+            return ENOMEM;
+        }
+
+        sys_memcpy(result_bin.data, path->data, path->size);
+    } else {
+        WIN32_FIND_DATAW data;
+        HANDLE handle;
+
+        WCHAR *name_buffer;
+        int name_length;
+
+        /* Reject path wildcards. */
+        if(wcspbrk(&((const WCHAR*)path->data)[4], L"?*")) {
+            return ENOENT;
+        }
+
+        handle = FindFirstFileW((const WCHAR*)path->data, &data);
+
+        if(handle == INVALID_HANDLE_VALUE) {
+            return windows_to_posix_errno(GetLastError());
+        }
+
+        FindClose(handle);
+
+        name_length = wcslen(data.cAlternateFileName);
+
+        if(name_length > 0) {
+            name_buffer = data.cAlternateFileName;
+        } else {
+            name_length = wcslen(data.cFileName);
+            name_buffer = data.cFileName;
+        }
+
+        /* Include NUL-terminator; it will be removed after normalization. */
+        name_length += 1;
+
+        if(!enif_alloc_binary(name_length * sizeof(WCHAR), &result_bin)) {
+            return ENOMEM;
+        }
+
+        sys_memcpy(result_bin.data, name_buffer, name_length * sizeof(WCHAR));
+    }
+
+    if(!normalize_path_result(&result_bin)) {
+        enif_release_binary(&result_bin);
+        return ENOMEM;
+    }
+
+    (*result) = enif_make_binary(env, &result_bin);
+
+    return 0;
+}
+
+static int windows_to_posix_errno(DWORD last_error) {
+    switch(last_error) {
+    case ERROR_SUCCESS:
+        return 0;
+    case ERROR_INVALID_FUNCTION:
+    case ERROR_INVALID_DATA:
+    case ERROR_INVALID_PARAMETER:
+    case ERROR_INVALID_TARGET_HANDLE:
+    case ERROR_INVALID_CATEGORY:
+    case ERROR_NEGATIVE_SEEK:
+        return EINVAL;
+    case ERROR_DIR_NOT_EMPTY:
+        return EEXIST;
+    case ERROR_BAD_FORMAT:
+        return ENOEXEC;
+    case ERROR_PATH_NOT_FOUND:
+    case ERROR_FILE_NOT_FOUND:
+    case ERROR_NO_MORE_FILES:
+    case ERROR_INVALID_NAME:
+        return ENOENT;
+    case ERROR_TOO_MANY_OPEN_FILES:
+        return EMFILE;
+    case ERROR_ACCESS_DENIED:
+    case ERROR_INVALID_ACCESS:
+    case ERROR_CURRENT_DIRECTORY:
+    case ERROR_SHARING_VIOLATION:
+    case ERROR_LOCK_VIOLATION:
+    case ERROR_INVALID_PASSWORD:
+    case ERROR_DRIVE_LOCKED:
+        return EACCES;
+    case ERROR_INVALID_HANDLE:
+        return EBADF;
+    case ERROR_NOT_ENOUGH_MEMORY:
+    case ERROR_OUTOFMEMORY:
+    case ERROR_OUT_OF_STRUCTURES:
+        return ENOMEM;
+    case ERROR_INVALID_DRIVE:
+    case ERROR_BAD_UNIT:
+    case ERROR_NOT_READY:
+    case ERROR_REM_NOT_LIST:
+    case ERROR_DUP_NAME:
+    case ERROR_BAD_NETPATH:
+    case ERROR_NETWORK_BUSY:
+    case ERROR_DEV_NOT_EXIST:
+    case ERROR_BAD_NET_NAME:
+        return ENXIO;
+    case ERROR_NOT_SAME_DEVICE:
+        return EXDEV;
+    case ERROR_WRITE_PROTECT:
+        return EROFS;
+    case ERROR_BAD_LENGTH:
+    case ERROR_BUFFER_OVERFLOW:
+        return E2BIG;
+    case ERROR_SEEK:
+    case ERROR_SECTOR_NOT_FOUND:
+        return ESPIPE;
+    case ERROR_NOT_DOS_DISK:
+        return ENODEV;
+    case ERROR_GEN_FAILURE:
+        return ENODEV;
+    case ERROR_SHARING_BUFFER_EXCEEDED:
+    case ERROR_NO_MORE_SEARCH_HANDLES:
+        return EMFILE;
+    case ERROR_HANDLE_EOF:
+    case ERROR_BROKEN_PIPE:
+        return EPIPE;
+    case ERROR_HANDLE_DISK_FULL:
+    case ERROR_DISK_FULL:
+        return ENOSPC;
+    case ERROR_NOT_SUPPORTED:
+        return ENOTSUP;
+    case ERROR_FILE_EXISTS:
+    case ERROR_ALREADY_EXISTS:
+    case ERROR_CANNOT_MAKE:
+        return EEXIST;
+    case ERROR_ALREADY_ASSIGNED:
+        return EBUSY;
+    case ERROR_NO_PROC_SLOTS:
+        return EAGAIN;
+    case ERROR_CANT_RESOLVE_FILENAME:
+        return EMLINK;
+    case ERROR_PRIVILEGE_NOT_HELD:
+        return EPERM;
+    case ERROR_ARENA_TRASHED:
+    case ERROR_INVALID_BLOCK:
+    case ERROR_BAD_ENVIRONMENT:
+    case ERROR_BAD_COMMAND:
+    case ERROR_CRC:
+    case ERROR_OUT_OF_PAPER:
+    case ERROR_READ_FAULT:
+    case ERROR_WRITE_FAULT:
+    case ERROR_WRONG_DISK:
+    case ERROR_NET_WRITE_FAULT:
+        return EIO;
+    default: /* not to do with files I expect. */
+        return EIO;
+    }
+}
diff --git a/erts/emulator/pcre/README.pcre_update.md b/erts/emulator/pcre/README.pcre_update.md
index 8caf575d31..599e3d0d12 100644
--- a/erts/emulator/pcre/README.pcre_update.md
+++ b/erts/emulator/pcre/README.pcre_update.md
@@ -2,7 +2,7 @@
 
 ## The basic changes to the PCRE library
 
-To work with the Erlang VM, PCRE has been changed in two important ways:
+To work with the Erlang VM, PCRE has been changed in three important ways:
 
 1. The main execution machine in pcre\_exec has been modified so that
 matching can be interrupted and restarted. This functionality utilizes
diff --git a/erts/emulator/sys/common/erl_check_io.c b/erts/emulator/sys/common/erl_check_io.c
index 799f67fc45..f93d4c1557 100644
--- a/erts/emulator/sys/common/erl_check_io.c
+++ b/erts/emulator/sys/common/erl_check_io.c
@@ -29,7 +29,6 @@
 #endif
 
 #define ERL_CHECK_IO_C__
-#define ERTS_WANT_BREAK_HANDLING
 #ifndef WANT_NONBLOCKING
 #  define WANT_NONBLOCKING
 #endif
@@ -44,76 +43,79 @@
 #define ERTS_WANT_TIMER_WHEEL_API
 #include "erl_time.h"
 
-#ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
-#  include "safe_hash.h"
-#  define DRV_EV_STATE_HTAB_SIZE 1024
+#if 0
+#define DEBUG_PRINT(FMT, ...) erts_printf(FMT "\r\n", ##__VA_ARGS__)
+#define DEBUG_PRINT_FD(FMT, STATE, ...)                                 \
+    DEBUG_PRINT("%d: " FMT " (ev=%s, ac=%s, flg=%d)",                   \
+                (STATE) ? (STATE)->fd : (ErtsSysFdType)-1, ##__VA_ARGS__, \
+                ev2str((STATE) ? (STATE)->events : ERTS_POLL_EV_NONE),  \
+                ev2str((STATE) ? (STATE)->active_events : ERTS_POLL_EV_NONE), \
+                (STATE) ? (STATE)->flags : ERTS_EV_FLAG_CLEAR)
+#define DEBUG_PRINT_MODE
+#else
+#define DEBUG_PRINT(...)
 #endif
 
-typedef char EventStateType;
-#define ERTS_EV_TYPE_NONE     ((EventStateType) 0)
-#define ERTS_EV_TYPE_DRV_SEL  ((EventStateType) 1) /* driver_select */
-#define ERTS_EV_TYPE_DRV_EV   ((EventStateType) 2) /* driver_event */
-#define ERTS_EV_TYPE_STOP_USE ((EventStateType) 3) /* pending stop_select */
-#define ERTS_EV_TYPE_NIF      ((EventStateType) 4) /* enif_select */
-#define ERTS_EV_TYPE_STOP_NIF ((EventStateType) 5) /* pending nif stop */
-
-typedef char EventStateFlags;
-#define ERTS_EV_FLAG_USED         ((EventStateFlags) 1)   /* ERL_DRV_USE has been turned on */
-#define ERTS_EV_FLAG_DEFER_IN_EV  ((EventStateFlags) 2)
-#define ERTS_EV_FLAG_DEFER_OUT_EV ((EventStateFlags) 4)
-
-#ifdef DEBUG
-#  define ERTS_ACTIVE_FD_INC 2
-#else
-#  define ERTS_ACTIVE_FD_INC 128
+#ifndef DEBUG_PRINT_FD
+#define DEBUG_PRINT_FD(...)
 #endif
 
-#define ERTS_CHECK_IO_POLL_RES_LEN 512
+#ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
+#  include "safe_hash.h"
+#  define DRV_EV_STATE_HTAB_SIZE 1024
+#endif
 
-#if defined(ERTS_KERNEL_POLL_VERSION)
-#  define ERTS_CIO_EXPORT(FUNC) FUNC ## _kp
-#elif defined(ERTS_NO_KERNEL_POLL_VERSION)
-#  define ERTS_CIO_EXPORT(FUNC) FUNC ## _nkp
+typedef enum {
+    ERTS_EV_TYPE_NONE     = 0,
+    ERTS_EV_TYPE_DRV_SEL  = 1, /* driver_select */
+    ERTS_EV_TYPE_STOP_USE = 2, /* pending stop_select */
+    ERTS_EV_TYPE_NIF      = 3, /* enif_select */
+    ERTS_EV_TYPE_STOP_NIF = 4  /* pending nif stop */
+} EventStateType;
+
+typedef enum {
+    ERTS_EV_FLAG_CLEAR         = 0,
+    ERTS_EV_FLAG_USED          = 1,   /* ERL_DRV_USE has been turned on */
+#ifdef ERTS_ENABLE_KERNEL_POLL
+    ERTS_EV_FLAG_FALLBACK      = 2,   /* Set when kernel poll rejected fd
+                                         and it was put in the nkp version */
 #else
-#  define ERTS_CIO_EXPORT(FUNC) FUNC
+    ERTS_EV_FLAG_FALLBACK      = ERTS_EV_FLAG_CLEAR,
 #endif
 
-#define ERTS_CIO_HAVE_DRV_EVENT \
-  (ERTS_POLL_USE_POLL && !ERTS_POLL_USE_KERNEL_POLL)
+    /* Combinations */
+    ERTS_EV_FLAG_USED_FALLBACK = ERTS_EV_FLAG_USED | ERTS_EV_FLAG_FALLBACK
+} EventStateFlags;
 
-#define ERTS_CIO_POLL_CTL	ERTS_POLL_EXPORT(erts_poll_control)
-#define ERTS_CIO_POLL_CTLV	ERTS_POLL_EXPORT(erts_poll_controlv)
-#define ERTS_CIO_POLL_WAIT	ERTS_POLL_EXPORT(erts_poll_wait)
-#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
-#define ERTS_CIO_POLL_AS_INTR 	ERTS_POLL_EXPORT(erts_poll_async_sig_interrupt)
-#endif
-#define ERTS_CIO_POLL_INTR 	ERTS_POLL_EXPORT(erts_poll_interrupt)
-#define ERTS_CIO_POLL_INTR_TMD	ERTS_POLL_EXPORT(erts_poll_interrupt_timed)
-#define ERTS_CIO_NEW_POLLSET 	ERTS_POLL_EXPORT(erts_poll_create_pollset)
-#define ERTS_CIO_FREE_POLLSET	ERTS_POLL_EXPORT(erts_poll_destroy_pollset)
-#define ERTS_CIO_POLL_MAX_FDS	ERTS_POLL_EXPORT(erts_poll_max_fds)
-#define ERTS_CIO_POLL_INIT	ERTS_POLL_EXPORT(erts_poll_init)
-#define ERTS_CIO_POLL_INFO	ERTS_POLL_EXPORT(erts_poll_info)
+#define flag2str(flags)                                                 \
+    ((flags) == ERTS_EV_FLAG_CLEAR ? "CLEAR" :                          \
+     ((flags) == ERTS_EV_FLAG_USED ? "USED" :                           \
+      ((flags) == ERTS_EV_FLAG_FALLBACK ? "FLBK" :                      \
+       ((flags) == ERTS_EV_FLAG_USED_FALLBACK ? "USED|FLBK" : "ERROR"))))
 
-#define GET_FD(fd) fd
+/* How many events that can be handled at once by one erts_poll_wait call */
+#define ERTS_CHECK_IO_POLL_RES_LEN 512
 
-static struct pollset_info
+/* Each I/O Poll Thread has one ErtsPollThread each. The ps field
+   can point to either a private ErtsPollSet or a shared one.
+   At the moment only kqueue and epoll pollsets can be
+   shared across threads.
+*/
+typedef struct erts_poll_thread
 {
-    ErtsPollSet ps;
-    erts_smp_atomic_t in_poll_wait;        /* set while doing poll */
-    struct {
-	int six; /* start index */
-	int eix; /* end index */
-	erts_smp_atomic32_t no;
-	int size;
-	ErtsSysFdType *array;
-    } active_fd;
-#ifdef ERTS_SMP
-    struct removed_fd* removed_list;       /* list of deselected fd's*/
-    erts_smp_spinlock_t removed_list_lock;
-#endif
-}pollset;
-#define NUM_OF_POLLSETS 1
+    ErtsPollSet *ps;
+    ErtsPollResFd *pollres;
+    int pollres_len;
+} ErtsPollThread;
+
+/* pollsetv contains pointers to the ErtsPollSets that are in use.
+ * Which pollset to use is determined by hashing the fd.
+ */
+static ErtsPollSet **pollsetv;
+#if ERTS_POLL_USE_FALLBACK
+static ErtsPollSet *flbk_pollset;
+#endif
+static ErtsPollThread *psiv;
 
 typedef struct {
 #ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
@@ -122,98 +124,151 @@ typedef struct {
     ErtsSysFdType fd;
     struct {
 	ErtsDrvSelectDataState *select;   /* ERTS_EV_TYPE_DRV_SEL */
-#if ERTS_CIO_HAVE_DRV_EVENT
-	ErtsDrvEventDataState *event;     /* ERTS_EV_TYPE_DRV_EV */
-#endif
         ErtsNifSelectDataState *nif;      /* ERTS_EV_TYPE_NIF */
         union {
             erts_driver_t*  drv_ptr;    /* ERTS_EV_TYPE_STOP_USE */
             ErtsResource* resource;   /* ERTS_EV_TYPE_STOP_NIF */
-        }stop;
+        } stop;
     } driver;
-    ErtsPollEvents events;
-    unsigned short remove_cnt; /* number of removed_fd's referring to this fd */
+    ErtsPollEvents events; /* The events that have been selected upon */
+    ErtsPollEvents active_events; /* The events currently active in the pollset */
     EventStateType type;
     EventStateFlags flags;
 } ErtsDrvEventState;
 
-#ifdef ERTS_SMP
-struct removed_fd {
-    struct removed_fd *next;
+struct drv_ev_state_shared {
+
+    union {
+        erts_mtx_t lck;
+        byte _cache_line_alignment[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(erts_mtx_t))];
+    } locks[ERTS_CHECK_IO_DRV_EV_STATE_LOCK_CNT];
+
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    ErtsSysFdType fd;
+    int max_fds;
+    erts_atomic_t len;
+    ErtsDrvEventState *v;
+    erts_mtx_t grow_lock; /* prevent lock-hogging of racing growers */
 #else
-    ErtsDrvEventState* state;
-    #ifdef DEBUG
-    ErtsSysFdType fd;
-    #endif
+    SafeHash tab;
+    int num_prealloc;
+    ErtsDrvEventState *prealloc_first;
+    erts_spinlock_t prealloc_lock;
 #endif
-
 };
-#endif
 
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-static int max_fds = -1;
-#endif
-#define DRV_EV_STATE_LOCK_CNT 16
-static union {
-    erts_smp_mtx_t lck;
-    byte _cache_line_alignment[64];
-}drv_ev_state_locks[DRV_EV_STATE_LOCK_CNT];
+int ERTS_WRITE_UNLIKELY(erts_no_pollsets) = 1;
+int ERTS_WRITE_UNLIKELY(erts_no_poll_threads) = 1;
+struct drv_ev_state_shared drv_ev_state;
 
-#ifdef ERTS_SMP
-static ERTS_INLINE erts_smp_mtx_t* fd_mtx(ErtsSysFdType fd)
-{
+static ERTS_INLINE int fd_hash(ErtsSysFdType fd) {
     int hash = (int)fd;
 # ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
     hash ^= (hash >> 9);
 # endif
-    return &drv_ev_state_locks[hash % DRV_EV_STATE_LOCK_CNT].lck;
+    return hash;
+}
+
+static ERTS_INLINE erts_mtx_t* fd_mtx(ErtsSysFdType fd)
+{
+    return &drv_ev_state.locks[fd_hash(fd) % ERTS_CHECK_IO_DRV_EV_STATE_LOCK_CNT].lck;
 }
-#else
-#  define fd_mtx(fd) NULL
-#endif
 
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
 
-static erts_smp_atomic_t drv_ev_state_len;
-static ErtsDrvEventState *drv_ev_state;
-static erts_smp_mtx_t drv_ev_state_grow_lock; /* prevent lock-hogging of racing growers */
+static ERTS_INLINE ErtsDrvEventState *get_drv_ev_state(ErtsSysFdType fd)
+{
+    return &drv_ev_state.v[(int) fd];
+}
+
+#define new_drv_ev_state(State, fd) (State)
+#define erase_drv_ev_state(State)
 
-#else
-static SafeHash drv_ev_state_tab;
-static int num_state_prealloc;
-static ErtsDrvEventState *state_prealloc_first;
-erts_smp_spinlock_t state_prealloc_lock;
+static ERTS_INLINE int grow_drv_ev_state(ErtsSysFdType fd) {
+    int i;
+    int old_len;
+    int new_len;
+
+    if ((unsigned)fd >= (unsigned)erts_atomic_read_nob(&drv_ev_state.len)) {
 
-static ERTS_INLINE ErtsDrvEventState *hash_get_drv_ev_state(ErtsSysFdType fd)
+	if (fd < 0 || fd >= drv_ev_state.max_fds)
+            return 0;
+
+        erts_mtx_lock(&drv_ev_state.grow_lock);
+        old_len = erts_atomic_read_nob(&drv_ev_state.len);
+        if (fd >= old_len) {
+            new_len = erts_poll_new_table_len(old_len, fd + 1);
+            if (new_len > drv_ev_state.max_fds)
+                new_len = drv_ev_state.max_fds;
+
+            for (i=0; i<ERTS_CHECK_IO_DRV_EV_STATE_LOCK_CNT; i++) { /* lock all fd's */
+                erts_mtx_lock(&drv_ev_state.locks[i].lck);
+            }
+            drv_ev_state.v = (drv_ev_state.v
+                              ? erts_realloc(ERTS_ALC_T_DRV_EV_STATE,
+                                             drv_ev_state.v,
+                                             sizeof(ErtsDrvEventState)*new_len)
+                              : erts_alloc(ERTS_ALC_T_DRV_EV_STATE,
+                                           sizeof(ErtsDrvEventState)*new_len));
+            ERTS_CT_ASSERT(ERTS_EV_TYPE_NONE == 0);
+            sys_memzero(drv_ev_state.v+old_len,
+                        sizeof(ErtsDrvEventState) * (new_len - old_len));
+            for (i = old_len; i < new_len; i++) {
+                drv_ev_state.v[i].fd = (ErtsSysFdType) i;
+            }
+            erts_atomic_set_nob(&drv_ev_state.len, new_len);
+            for (i=0; i<ERTS_CHECK_IO_DRV_EV_STATE_LOCK_CNT; i++) {
+                erts_mtx_unlock(&drv_ev_state.locks[i].lck);
+            }
+        }
+        /*else already grown by racing thread */
+
+        erts_mtx_unlock(&drv_ev_state.grow_lock);
+    }
+    return 1;
+}
+
+static int drv_ev_state_len(void)
+{
+    return erts_atomic_read_nob(&drv_ev_state.len);
+}
+
+#else /* !ERTS_SYS_CONTINOUS_FD_NUMBERS */
+
+static ERTS_INLINE ErtsDrvEventState *get_drv_ev_state(ErtsSysFdType fd)
 {
     ErtsDrvEventState tmpl;
     tmpl.fd = fd;
-    return  (ErtsDrvEventState *) safe_hash_get(&drv_ev_state_tab, (void *) &tmpl);
+    return  (ErtsDrvEventState *) safe_hash_get(&drv_ev_state.tab, (void *) &tmpl);
 }
 
-static ERTS_INLINE ErtsDrvEventState* hash_new_drv_ev_state(ErtsSysFdType fd)
+static ERTS_INLINE ErtsDrvEventState* new_drv_ev_state(ErtsDrvEventState *state,
+                                                       ErtsSysFdType fd)
 {
     ErtsDrvEventState tmpl;
+
+    if (state)
+        return state;
+
     tmpl.fd = fd;
     tmpl.driver.select = NULL;
-#if ERTS_CIO_HAVE_DRV_EVENT
-    tmpl.driver.event = NULL;
-#endif
     tmpl.driver.nif = NULL;
     tmpl.driver.stop.drv_ptr = NULL;
     tmpl.events = 0;
-    tmpl.remove_cnt = 0;
+    tmpl.active_events = 0;
     tmpl.type = ERTS_EV_TYPE_NONE;
     tmpl.flags = 0;
-    return  (ErtsDrvEventState *) safe_hash_put(&drv_ev_state_tab, (void *) &tmpl);
+
+    return  (ErtsDrvEventState *) safe_hash_put(&drv_ev_state.tab, (void *) &tmpl);
+}
+
+static ERTS_INLINE void erase_drv_ev_state(ErtsDrvEventState *state)
+{
+    safe_hash_erase(&drv_ev_state.tab, (void *) state);
 }
 
-static ERTS_INLINE void hash_erase_drv_ev_state(ErtsDrvEventState *state)
+static int drv_ev_state_len(void)
 {
-    ASSERT(state->remove_cnt == 0);
-    safe_hash_erase(&drv_ev_state_tab, (void *) state);
+    return erts_atomic_read_nob(&drv_ev_state.tab.nitems);
 }
 
 #endif /* !ERTS_SYS_CONTINOUS_FD_NUMBERS */
@@ -233,52 +288,47 @@ static void print_nif_select_op(erts_dsprintf_buf_t*, ErtsSysFdType,
 static void drv_select_large_fd_error(ErlDrvPort, ErtsSysFdType, int, int);
 static void nif_select_large_fd_error(ErtsSysFdType, int, ErtsResource*,Eterm ref);
 #endif
-#if ERTS_CIO_HAVE_DRV_EVENT
-static void drv_event_steal(ErlDrvPort ix, ErtsDrvEventState *state,
-			ErlDrvEventData event_data);
-static void print_drv_event_op(erts_dsprintf_buf_t *dsbufp,
-                               ErlDrvPort, ErtsSysFdType, ErlDrvEventData);
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-static void event_large_fd_error(ErlDrvPort, ErtsSysFdType, ErlDrvEventData);
-#endif
-#endif
 static void
 steal_pending_stop_use(erts_dsprintf_buf_t*, ErlDrvPort, ErtsDrvEventState*,
                        int mode, int on);
 static void
 steal_pending_stop_nif(erts_dsprintf_buf_t *dsbufp, ErtsResource*,
                        ErtsDrvEventState *state, int mode, int on);
-
-#ifdef ERTS_SMP
-ERTS_SCHED_PREF_QUICK_ALLOC_IMPL(removed_fd, struct removed_fd, 64, ERTS_ALC_T_FD_LIST)
+static ERTS_INLINE void
+check_fd_cleanup(ErtsDrvEventState *state,
+		 ErtsDrvSelectDataState **free_select,
+                 ErtsNifSelectDataState **free_nif);
+static ERTS_INLINE void iready(Eterm id, ErtsDrvEventState *state);
+static ERTS_INLINE void oready(Eterm id, ErtsDrvEventState *state);
+#ifdef DEBUG_PRINT_MODE
+static char *drvmode2str(int mode);
+static char *nifmode2str(enum ErlNifSelectFlags mode);
 #endif
 
 static ERTS_INLINE void
-init_iotask(ErtsIoTask *io_task)
+init_iotask(ErtsIoTask *io_task, ErtsSysFdType fd)
 {
     erts_port_task_handle_init(&io_task->task);
-    erts_smp_atomic_init_nob(&io_task->executed_time, ~((erts_aint_t) 0));
+    io_task->fd = fd;
 }
 
 static ERTS_INLINE int
-is_iotask_active(ErtsIoTask *io_task, erts_aint_t current_cio_time)
-{    
+is_iotask_active(ErtsIoTask *io_task)
+{
     if (erts_port_task_is_scheduled(&io_task->task))
 	return 1;
-    if (erts_smp_atomic_read_nob(&io_task->executed_time) == current_cio_time)
-	return 1;
     return 0;
 }
 
 static ERTS_INLINE ErtsDrvSelectDataState *
-alloc_drv_select_data(void)
+alloc_drv_select_data(ErtsSysFdType fd)
 {
     ErtsDrvSelectDataState *dsp = erts_alloc(ERTS_ALC_T_DRV_SEL_D_STATE,
 					     sizeof(ErtsDrvSelectDataState));
     dsp->inport = NIL;
     dsp->outport = NIL;
-    init_iotask(&dsp->iniotask);
-    init_iotask(&dsp->outiotask);
+    init_iotask(&dsp->iniotask, fd);
+    init_iotask(&dsp->outiotask, fd);
     return dsp;
 }
 
@@ -289,8 +339,6 @@ alloc_nif_select_data(void)
 					     sizeof(ErtsNifSelectDataState));
     dsp->in.pid = NIL;
     dsp->out.pid = NIL;
-    dsp->in.ddeselect_cnt = 0;
-    dsp->out.ddeselect_cnt = 0;
     return dsp;
 }
 
@@ -308,209 +356,136 @@ free_nif_select_data(ErtsNifSelectDataState *dsp)
     erts_free(ERTS_ALC_T_NIF_SEL_D_STATE, dsp);
 }
 
-#if ERTS_CIO_HAVE_DRV_EVENT
-
-static ERTS_INLINE ErtsDrvEventDataState *
-alloc_drv_event_data(void)
+static ERTS_INLINE int
+get_pollset_id(ErtsSysFdType fd)
 {
-    ErtsDrvEventDataState *dep = erts_alloc(ERTS_ALC_T_DRV_EV_D_STATE,
-					    sizeof(ErtsDrvEventDataState));
-    dep->port = NIL;
-    dep->data = NULL;
-    dep->removed_events = 0;
-#if ERTS_CIO_DEFER_ACTIVE_EVENTS
-    dep->deferred_events = 0;
-#endif
-    init_iotask(&dep->iotask);
-    return dep;
+    return fd_hash(fd) % erts_no_pollsets;
 }
 
-static ERTS_INLINE void
-free_drv_event_data(ErtsDrvEventDataState *dep)
+static ERTS_INLINE ErtsPollSet *
+get_pollset(ErtsSysFdType fd)
 {
-    ASSERT(!erts_port_task_is_scheduled(&dep->iotask.task));
-    erts_free(ERTS_ALC_T_DRV_EV_D_STATE, dep);   
+    return pollsetv[get_pollset_id(fd)];
 }
 
-#endif /* ERTS_CIO_HAVE_DRV_EVENT */
-
-static ERTS_INLINE void
-remember_removed(ErtsDrvEventState *state, struct pollset_info* psi)
+#if ERTS_POLL_USE_FALLBACK
+static ERTS_INLINE ErtsPollSet *
+get_fallback(void)
 {
-#ifdef ERTS_SMP
-    struct removed_fd *fdlp;
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_mtx_is_locked(fd_mtx(state->fd)));
-    if (erts_smp_atomic_read_nob(&psi->in_poll_wait)) {
-	state->remove_cnt++;
-	ASSERT(state->remove_cnt > 0);
-	fdlp = removed_fd_alloc();
-    #if defined(ERTS_SYS_CONTINOUS_FD_NUMBERS) || defined(DEBUG)
-    	fdlp->fd = state->fd;
-    #endif
-    #ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
-	fdlp->state = state;
-    #endif
-	erts_smp_spin_lock(&psi->removed_list_lock);
-	fdlp->next = psi->removed_list;
-	psi->removed_list = fdlp;
-	erts_smp_spin_unlock(&psi->removed_list_lock);
-    }
-#endif
+    return flbk_pollset;
 }
+#endif
 
-
-static ERTS_INLINE int
-is_removed(ErtsDrvEventState *state)
+/*
+ * Place a fd within a pollset. This will automatically use
+ * the fallback ps if needed.
+ */
+static ERTS_INLINE ErtsPollEvents
+erts_io_control_wakeup(ErtsDrvEventState *state, ErtsPollOp op,
+                       ErtsPollEvents pe, int *wake_poller)
 {
-#ifdef ERTS_SMP
-    /* Note that there is a possible race here, where an fd is removed
-       (increasing remove_cnt) and then added again just before erts_poll_wait
-       is called by erts_check_io. Any polled event on the re-added fd will then
-       be falsely ignored. But that does not matter, as the event will trigger
-       again next time erl_check_io is called. */
-    return state->remove_cnt > 0;
-#else
-    return 0;
+    ErtsSysFdType fd = state->fd;
+    ErtsPollEvents res = 0;
+    EventStateFlags flags = state->flags;
+
+    ERTS_LC_ASSERT(erts_lc_mtx_is_locked(fd_mtx(state->fd)));
+
+    if (!(flags & ERTS_EV_FLAG_FALLBACK)) {
+        res = erts_poll_control(get_pollset(fd), fd, op, pe, wake_poller);
+
+#if ERTS_POLL_USE_FALLBACK
+        if (op == ERTS_POLL_OP_ADD && res == ERTS_POLL_EV_NVAL) {
+            /* When an add fails with NVAL, the poll/kevent operation could not
+               put that fd in the pollset, so we instead put it into a fallback pollset */
+            state->flags |= ERTS_EV_FLAG_FALLBACK;
+            res = erts_poll_control_flbk(get_fallback(), fd, op, pe, wake_poller);
+        }
+    } else {
+        ASSERT(op != ERTS_POLL_OP_ADD);
+        res = erts_poll_control_flbk(get_fallback(), fd, op, pe, wake_poller);
 #endif
+    }
+
+    return res;
 }
 
-static void
-forget_removed(struct pollset_info* psi)
+static ERTS_INLINE ErtsPollEvents
+erts_io_control(ErtsDrvEventState *state, ErtsPollOp op, ErtsPollEvents pe)
 {
-#ifdef ERTS_SMP
-    struct removed_fd* fdlp;
-    struct removed_fd* tofree;
+    int wake_poller = 0;
+    return erts_io_control_wakeup(state, op, pe, &wake_poller);
+}
 
-    /* Fast track: if (atomic_ptr(removed_list)==NULL) return; */
+/* ToDo: Was inline in erl_check_io.h but now need struct erts_poll_thread */
+void
+erts_io_notify_port_task_executed(ErtsPortTaskType type,
+                                  ErtsPortTaskHandle *pthp,
+                                  void (*reset_handle)(ErtsPortTaskHandle *))
+{
+    ErtsIoTask *itp = ErtsContainerStruct(pthp, ErtsIoTask, task);
+    ErtsSysFdType fd = itp->fd;
+    erts_mtx_t *mtx = fd_mtx(fd);
+    int active_events;
+    ErtsDrvEventState *state;
+    ErtsDrvSelectDataState *free_select = NULL;
+    ErtsNifSelectDataState *free_nif = NULL;
 
-    erts_smp_spin_lock(&psi->removed_list_lock);
-    fdlp = psi->removed_list;
-    psi->removed_list = NULL;
-    erts_smp_spin_unlock(&psi->removed_list_lock);
+    erts_mtx_lock(mtx);
+    state = get_drv_ev_state(fd);
 
-    while (fdlp) {
-        ErtsResource* resource = NULL;
-	erts_driver_t* drv_ptr = NULL;
-	erts_smp_mtx_t* mtx;
-	ErtsSysFdType fd;
-	ErtsDrvEventState *state;
+    active_events = state->active_events;
 
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-	fd = fdlp->fd;
-	mtx = fd_mtx(fd);
-	erts_smp_mtx_lock(mtx);
-	state = &drv_ev_state[(int) fd];
-#else
-	state = fdlp->state;
-	fd = state->fd;
-	ASSERT(fd == fdlp->fd);
-	mtx = fd_mtx(fd);
-	erts_smp_mtx_lock(mtx);
-#endif
-	ASSERT(state->remove_cnt > 0);
-	if (--state->remove_cnt == 0) {
-	    switch (state->type) {
-	    case ERTS_EV_TYPE_STOP_NIF:
-		/* Now we can call stop */
-		resource = state->driver.stop.resource;
-                state->driver.stop.resource = NULL;
-                ASSERT(resource);
-		state->type = ERTS_EV_TYPE_NONE;
-		state->flags &= ~ERTS_EV_FLAG_USED;
-                goto case_ERTS_EV_TYPE_NONE;
-
-	    case ERTS_EV_TYPE_STOP_USE:
-		/* Now we can call stop_select */
-		drv_ptr = state->driver.stop.drv_ptr;
-		ASSERT(drv_ptr);
-		state->type = ERTS_EV_TYPE_NONE;
-		state->flags &= ~ERTS_EV_FLAG_USED;
-		state->driver.stop.drv_ptr = NULL;
-		/* Fall through */
-            case ERTS_EV_TYPE_NONE:
-            case_ERTS_EV_TYPE_NONE:
-#ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
-		hash_erase_drv_ev_state(state);
-#endif
-		break;
-	    case ERTS_EV_TYPE_DRV_SEL:
-	    case ERTS_EV_TYPE_DRV_EV:
-		break;
-	    default:
-		ASSERT(0);
-	    }
-	}
-	erts_smp_mtx_unlock(mtx);
-	if (drv_ptr) {
-	    int was_unmasked = erts_block_fpe();
-	    DTRACE1(driver_stop_select, drv_ptr->name);
-	    LTTNG1(driver_stop_select, drv_ptr->name);
-	    (*drv_ptr->stop_select) ((ErlDrvEvent) fd, NULL);
-	    erts_unblock_fpe(was_unmasked);
-	    if (drv_ptr->handle) {
-		erts_ddll_dereference_driver(drv_ptr->handle);
-	    }
-	}
-        if (resource) {
-            erts_resource_stop(resource, (ErlNifEvent)fd, 0);
-            enif_release_resource(resource->data);
-        }
+    switch (type) {
+    case ERTS_PORT_TASK_INPUT:
+
+        DEBUG_PRINT_FD("executed ready_input", state);
 
-	tofree = fdlp;
-	fdlp = fdlp->next;
-	removed_fd_free(tofree);
+        ASSERT(!(state->active_events & ERTS_POLL_EV_IN));
+        if (state->events & ERTS_POLL_EV_IN)
+            active_events |= ERTS_POLL_EV_IN;
+        break;
+    case ERTS_PORT_TASK_OUTPUT:
+
+        DEBUG_PRINT_FD("executed ready_output", state);
+
+        ASSERT(!(state->active_events & ERTS_POLL_EV_OUT));
+        if (state->events & ERTS_POLL_EV_OUT)
+            active_events |= ERTS_POLL_EV_OUT;
+        break;
+    default:
+        erts_exit(ERTS_ABORT_EXIT, "Invalid IO port task type");
+        break;
     }
-#endif /* ERTS_SMP */
-}
 
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-static void
-grow_drv_ev_state(int min_ix)
-{
-    int i;
-    int old_len;
-    int new_len;
+    reset_handle(pthp);
 
-    erts_smp_mtx_lock(&drv_ev_state_grow_lock);
-    old_len = erts_smp_atomic_read_nob(&drv_ev_state_len);
-    if (min_ix >= old_len) {
-        new_len = erts_poll_new_table_len(old_len, min_ix + 1);
-        if (new_len > max_fds)
-            new_len = max_fds;
+    if (active_events) {
+        /* This is not needed if active_events has not changed */
+        if (state->active_events != active_events) {
+            ErtsPollEvents new_events;
+            state->active_events = active_events;
+            new_events = erts_io_control(state, ERTS_POLL_OP_MOD, active_events);
 
-	for (i=0; i<DRV_EV_STATE_LOCK_CNT; i++) { /* lock all fd's */
-	    erts_smp_mtx_lock(&drv_ev_state_locks[i].lck);
-	}
-	drv_ev_state = (drv_ev_state
-			? erts_realloc(ERTS_ALC_T_DRV_EV_STATE,
-				       drv_ev_state,
-				       sizeof(ErtsDrvEventState)*new_len)
-			: erts_alloc(ERTS_ALC_T_DRV_EV_STATE,
-				     sizeof(ErtsDrvEventState)*new_len));
-	for (i = old_len; i < new_len; i++) {
-	    drv_ev_state[i].fd = (ErtsSysFdType) i;
-	    drv_ev_state[i].driver.select = NULL;
-#if ERTS_CIO_HAVE_DRV_EVENT
-	    drv_ev_state[i].driver.event = NULL;
-#endif
-	    drv_ev_state[i].driver.stop.drv_ptr = NULL;
-            drv_ev_state[i].driver.nif = NULL;
-	    drv_ev_state[i].events = 0;
-	    drv_ev_state[i].remove_cnt = 0;
-	    drv_ev_state[i].type = ERTS_EV_TYPE_NONE;
-	    drv_ev_state[i].flags = 0;
-	}
-	erts_smp_atomic_set_nob(&drv_ev_state_len, new_len);
-	for (i=0; i<DRV_EV_STATE_LOCK_CNT; i++) {
-	    erts_smp_mtx_unlock(&drv_ev_state_locks[i].lck);
-	}
+            /* We were unable to re-insert the fd into the pollset, signal the callback. */
+            if (new_events & (ERTS_POLL_EV_ERR|ERTS_POLL_EV_NVAL)) {
+                if (active_events & ERTS_POLL_EV_IN)
+                    iready(state->driver.select->inport, state);
+                if (active_events & ERTS_POLL_EV_OUT)
+                    oready(state->driver.select->outport, state);
+                state->active_events = 0;
+            }
+        }
+    } else {
+        check_fd_cleanup(state, &free_select, &free_nif);
     }
-    /*else already grown by racing thread */
 
-    erts_smp_mtx_unlock(&drv_ev_state_grow_lock);
-}
-#endif /* ERTS_SYS_CONTINOUS_FD_NUMBERS */
+    erts_mtx_unlock(mtx);
 
+    if (free_select)
+        free_drv_select_data(free_select);
+    if (free_nif)
+        free_nif_select_data(free_nif);
+}
 
 static ERTS_INLINE void
 abort_task(Eterm id, ErtsPortTaskHandle *pthp, EventStateType type)
@@ -527,13 +502,6 @@ abort_tasks(ErtsDrvEventState *state, int mode)
     switch (mode) {
     case 0: check_type:
 	switch (state->type) {
-#if ERTS_CIO_HAVE_DRV_EVENT
-	case ERTS_EV_TYPE_DRV_EV:
-	    abort_task(state->driver.event->port,
-		       &state->driver.event->iotask.task,
-		       ERTS_EV_TYPE_DRV_EV);
-	    return;
-#endif
         case ERTS_EV_TYPE_NIF:
 	case ERTS_EV_TYPE_NONE:
 	    return;
@@ -563,16 +531,14 @@ abort_tasks(ErtsDrvEventState *state, int mode)
 static void
 deselect(ErtsDrvEventState *state, int mode)
 {
-    int do_wake = 0;
     ErtsPollEvents rm_events;
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_mtx_is_locked(fd_mtx(state->fd)));
-    ASSERT(state->events);
+    ERTS_LC_ASSERT(erts_lc_mtx_is_locked(fd_mtx(state->fd)));
 
     abort_tasks(state, mode);
 
-    if (!mode)
+    if (!mode) {
 	rm_events = state->events;
-    else {
+    } else {
 	rm_events = 0;
 	ASSERT(state->type == ERTS_EV_TYPE_DRV_SEL);
 	if (mode & ERL_DRV_READ) {
@@ -585,67 +551,63 @@ deselect(ErtsDrvEventState *state, int mode)
 	}
     }
 
-    state->events = ERTS_CIO_POLL_CTL(pollset.ps, state->fd, rm_events, 0, &do_wake);
+    state->events &= ~rm_events;
+    state->active_events &= ~rm_events;
 
     if (!(state->events)) {
+        erts_io_control(state, ERTS_POLL_OP_DEL, 0);
 	switch (state->type) {
         case ERTS_EV_TYPE_NIF:
             state->driver.nif->in.pid = NIL;
             state->driver.nif->out.pid = NIL;
-            state->driver.nif->in.ddeselect_cnt = 0;
-            state->driver.nif->out.ddeselect_cnt = 0;
-            enif_release_resource(state->driver.stop.resource);
+            enif_release_resource(state->driver.stop.resource->data);
             state->driver.stop.resource = NULL;
             break;
 	case ERTS_EV_TYPE_DRV_SEL:
 	    state->driver.select->inport = NIL;
 	    state->driver.select->outport = NIL;
 	    break;
-#if ERTS_CIO_HAVE_DRV_EVENT
-	case ERTS_EV_TYPE_DRV_EV:
-	    state->driver.event->port = NIL;
-	    state->driver.event->data = NULL;
-	    state->driver.event->removed_events = (ErtsPollEvents) 0;
-	    break;
-#endif
 	case ERTS_EV_TYPE_NONE:
 	    break;
 	default:
 	    ASSERT(0);
 	    break;
 	}
-	    
 	state->type = ERTS_EV_TYPE_NONE;
-	state->flags &= ~ERTS_EV_FLAG_USED;
-	remember_removed(state, &pollset);
+	state->flags = 0;
+    } else {
+        ErtsPollEvents new_events =
+            erts_io_control(state, ERTS_POLL_OP_MOD, state->active_events);
+
+        /* We were unable to re-insert the fd into the pollset, signal the callback. */
+        if (new_events & (ERTS_POLL_EV_ERR|ERTS_POLL_EV_NVAL)) {
+            if (state->active_events & ERTS_POLL_EV_IN)
+                iready(state->driver.select->inport, state);
+            if (state->active_events & ERTS_POLL_EV_OUT)
+                oready(state->driver.select->outport, state);
+            state->active_events = 0;
+        }
     }
 }
 
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-#  define IS_FD_UNKNOWN(state) ((state)->type == ERTS_EV_TYPE_NONE && (state)->remove_cnt == 0)
+#  define IS_FD_UNKNOWN(state) ((state)->type == ERTS_EV_TYPE_NONE)
 #else
 #  define IS_FD_UNKNOWN(state) ((state) == NULL)
 #endif
 
 static ERTS_INLINE void
 check_fd_cleanup(ErtsDrvEventState *state,
-#if ERTS_CIO_HAVE_DRV_EVENT
-		 ErtsDrvEventDataState **free_event,
-#endif
 		 ErtsDrvSelectDataState **free_select,
                  ErtsNifSelectDataState **free_nif)
 {
-    erts_aint_t current_cio_time;
-
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_mtx_is_locked(fd_mtx(state->fd)));
-
-    current_cio_time = erts_smp_atomic_read_acqb(&erts_check_io_time);
+    ERTS_LC_ASSERT(erts_lc_mtx_is_locked(fd_mtx(state->fd)));
     *free_select = NULL;
     if (state->driver.select
 	&& (state->type != ERTS_EV_TYPE_DRV_SEL)
-	&& !is_iotask_active(&state->driver.select->iniotask, current_cio_time)
-	&& !is_iotask_active(&state->driver.select->outiotask, current_cio_time)) {
-	
+	&& !is_iotask_active(&state->driver.select->iniotask)
+	&& !is_iotask_active(&state->driver.select->outiotask)) {
+
 	*free_select = state->driver.select;
 	state->driver.select = NULL;
     }
@@ -656,382 +618,85 @@ check_fd_cleanup(ErtsDrvEventState *state,
         state->driver.nif = NULL;
     }
 
-#if ERTS_CIO_HAVE_DRV_EVENT
-    *free_event = NULL;
-    if (state->driver.event
-	&& (state->type != ERTS_EV_TYPE_DRV_EV)
-	&& !is_iotask_active(&state->driver.event->iotask,  current_cio_time)) {
-	
-	*free_event = state->driver.event;
-	state->driver.event = NULL;
-    }
-#endif
-
-#ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
     if (((state->type != ERTS_EV_TYPE_NONE)
-	 | state->remove_cnt
-#if ERTS_CIO_HAVE_DRV_EVENT
-	 | (state->driver.event != NULL)
-#endif
+         | (state->driver.nif != NULL)
 	 | (state->driver.select != NULL)) == 0) {
 
-	hash_erase_drv_ev_state(state);
-
+	erase_drv_ev_state(state);
     }
-#endif
 }
 
-static ERTS_INLINE int
-check_cleanup_active_fd(ErtsSysFdType fd,
-#if ERTS_CIO_DEFER_ACTIVE_EVENTS
-			ErtsPollControlEntry *pce,
-			int *pce_ix,
-#endif
-			erts_aint_t current_cio_time,
-                        int may_sleep)
-{
-    ErtsDrvEventState *state;
-    int active = 0;
-    erts_smp_mtx_t *mtx = fd_mtx(fd);
-    void *free_select = NULL;
-    void *free_nif = NULL;
-#if ERTS_CIO_HAVE_DRV_EVENT
-    void *free_event = NULL;
-#endif
-#if ERTS_CIO_DEFER_ACTIVE_EVENTS
-    ErtsPollEvents evon = 0, evoff = 0;
-#endif
-
-    erts_smp_mtx_lock(mtx);
-
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    state = &drv_ev_state[(int) fd];
+#ifdef __WIN32__
+# define MUST_DEFER(MAY_SLEEP) 1
 #else
-    state = hash_get_drv_ev_state(fd); /* may be NULL! */
-    if (state)
+# define MUST_DEFER(MAY_SLEEP) (MAY_SLEEP)
 #endif
-    {
-	if (state->driver.select) {
-#if ERTS_CIO_DEFER_ACTIVE_EVENTS
-	    if (is_iotask_active(&state->driver.select->iniotask, current_cio_time)) {
-		active = 1;
-		if ((state->events & ERTS_POLL_EV_IN)
-		    && !(state->flags & ERTS_EV_FLAG_DEFER_IN_EV)) {
-		    evoff |= ERTS_POLL_EV_IN;
-		    state->flags |= ERTS_EV_FLAG_DEFER_IN_EV;
-		}
-	    }
-	    else if (state->flags & ERTS_EV_FLAG_DEFER_IN_EV) {
-		if (state->events & ERTS_POLL_EV_IN)
-		    evon |= ERTS_POLL_EV_IN;
-		state->flags &= ~ERTS_EV_FLAG_DEFER_IN_EV;
-	    }
-	    if (is_iotask_active(&state->driver.select->outiotask, current_cio_time)) {
-		active = 1;
-		if ((state->events & ERTS_POLL_EV_OUT)
-		    && !(state->flags & ERTS_EV_FLAG_DEFER_OUT_EV)) {
-		    evoff |= ERTS_POLL_EV_OUT;
-		    state->flags |= ERTS_EV_FLAG_DEFER_OUT_EV;
-		}
-	    }
-	    else if (state->flags & ERTS_EV_FLAG_DEFER_OUT_EV) {
-		if (state->events & ERTS_POLL_EV_OUT)
-		    evon |= ERTS_POLL_EV_OUT;
-		state->flags &= ~ERTS_EV_FLAG_DEFER_OUT_EV;
-	    }
-	    if (active)
-		(void) 0;
-	    else
-#else
-	    if (is_iotask_active(&state->driver.select->iniotask, current_cio_time)
-		|| is_iotask_active(&state->driver.select->outiotask, current_cio_time))
-		active = 1;
-	    else
-#endif
-		if (state->type != ERTS_EV_TYPE_DRV_SEL) {
-		free_select = state->driver.select;
-		state->driver.select = NULL;
-	    }
-	}
-
-        if (state->driver.nif) {
-            ErtsPollEvents rm_events = 0;
-            if (state->driver.nif->in.ddeselect_cnt) {
-                ASSERT(state->type == ERTS_EV_TYPE_NIF);
-                ASSERT(state->events & ERTS_POLL_EV_IN);
-                ASSERT(is_nil(state->driver.nif->in.pid));
-                if (may_sleep || state->driver.nif->in.ddeselect_cnt == 1) {
-                    rm_events = ERTS_POLL_EV_IN;
-                    state->driver.nif->in.ddeselect_cnt = 0;
-                }
-            }
-            if (state->driver.nif->out.ddeselect_cnt) {
-                ASSERT(state->type == ERTS_EV_TYPE_NIF);
-                ASSERT(state->events & ERTS_POLL_EV_OUT);
-                ASSERT(is_nil(state->driver.nif->out.pid));
-                if (may_sleep || state->driver.nif->out.ddeselect_cnt == 1) {
-                    rm_events |= ERTS_POLL_EV_OUT;
-                    state->driver.nif->out.ddeselect_cnt = 0;
-                }
-            }
-            if (rm_events) {
-                int do_wake = 0;
-                state->events = ERTS_CIO_POLL_CTL(pollset.ps, state->fd,
-                                                  rm_events, 0, &do_wake);
-            }
-            if (state->events)
-                active = 1;
-            else if (state->type != ERTS_EV_TYPE_NIF) {
-                free_nif = state->driver.nif;
-                state->driver.nif = NULL;
-            }
-        }
-
-#if ERTS_CIO_HAVE_DRV_EVENT
-	if (state->driver.event) {
-	    if (is_iotask_active(&state->driver.event->iotask, current_cio_time)) {
-#if ERTS_CIO_DEFER_ACTIVE_EVENTS
-		ErtsPollEvents evs = state->events & ~state->driver.event->deferred_events;
-		if (evs) {
-		    evoff |= evs;
-		    state->driver.event->deferred_events |= evs;
-		}
-#endif
-		active = 1;
-	    }
-	    else if (state->type != ERTS_EV_TYPE_DRV_EV) {
-		free_event = state->driver.event;
-		state->driver.event = NULL;
-	    }
-#if ERTS_CIO_DEFER_ACTIVE_EVENTS
-	    else {
-		ErtsPollEvents evs = state->events & state->driver.event->deferred_events;
-		if (evs) {
-		    evon |= evs;
-		    state->driver.event->deferred_events = 0;
-		}
-	    }
-#endif
-
-	}
-#endif
-
-#ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
-	if (((state->type != ERTS_EV_TYPE_NONE) | state->remove_cnt | active) == 0)
-	    hash_erase_drv_ev_state(state);
-#endif
-
-    }
-
-    erts_smp_mtx_unlock(mtx);
-
-    if (free_select)
-	free_drv_select_data(free_select);
-    if (free_nif)
-        free_nif_select_data(free_nif);
-#if ERTS_CIO_HAVE_DRV_EVENT
-    if (free_event)
-	free_drv_event_data(free_event);
-#endif
-
-#if ERTS_CIO_DEFER_ACTIVE_EVENTS
-    if (evoff) {
-	ErtsPollControlEntry *pcep = &pce[(*pce_ix)++];
-	pcep->fd = fd;
-	pcep->events = evoff;
-	pcep->on = 0;
-    }
-    if (evon) {
-	ErtsPollControlEntry *pcep = &pce[(*pce_ix)++];
-	pcep->fd = fd;
-	pcep->events = evon;
-	pcep->on = 1;
-    }
-#endif
-
-    return active;
-}
-
-static void
-check_cleanup_active_fds(erts_aint_t current_cio_time, int may_sleep)
-{
-    int six = pollset.active_fd.six;
-    int eix = pollset.active_fd.eix;
-    erts_aint32_t no = erts_smp_atomic32_read_dirty(&pollset.active_fd.no);
-    int size = pollset.active_fd.size;
-    int ix = six;
-#if ERTS_CIO_DEFER_ACTIVE_EVENTS
-    /* every fd might add two entries */
-    Uint pce_sz = 2*sizeof(ErtsPollControlEntry)*no;
-    ErtsPollControlEntry *pctrl_entries = (pce_sz
-					   ? erts_alloc(ERTS_ALC_T_TMP, pce_sz)
-					   : NULL);
-    int pctrl_ix = 0;
-#endif
-
-    while (ix != eix) {
-	ErtsSysFdType fd = pollset.active_fd.array[ix];
-	int nix = ix + 1;
-	if (nix >= size)
-	    nix = 0;
-	ASSERT(fd != ERTS_SYS_FD_INVALID);
-	if (!check_cleanup_active_fd(fd,
-#if ERTS_CIO_DEFER_ACTIVE_EVENTS
-				     pctrl_entries,
-				     &pctrl_ix,
-#endif
-				     current_cio_time,
-                                     may_sleep)) {
-	    no--;
-	    if (ix == six) {
-#ifdef DEBUG
-		pollset.active_fd.array[ix] = ERTS_SYS_FD_INVALID;
-#endif
-		six = nix;
-	    }
-	    else {
-		pollset.active_fd.array[ix] = pollset.active_fd.array[six];
-#ifdef DEBUG
-		pollset.active_fd.array[six] = ERTS_SYS_FD_INVALID;
-#endif
-		six++;
-		if (six >= size)
-		    six = 0;
-	    }
-	}
-	ix = nix;
-    }
-
-#if ERTS_CIO_DEFER_ACTIVE_EVENTS
-    ASSERT(pctrl_ix <= pce_sz/sizeof(ErtsPollControlEntry));
-    if (pctrl_ix)
-	ERTS_CIO_POLL_CTLV(pollset.ps, pctrl_entries, pctrl_ix);
-    if (pctrl_entries)
-	erts_free(ERTS_ALC_T_TMP, pctrl_entries);
-#endif
-
-    pollset.active_fd.six = six;
-    pollset.active_fd.eix = eix;
-    erts_smp_atomic32_set_relb(&pollset.active_fd.no, no);
-}
-
-static void grow_active_fds(void)
-{
-    ASSERT(pollset.active_fd.six == pollset.active_fd.eix);
-    pollset.active_fd.six = 0;
-    pollset.active_fd.eix = pollset.active_fd.size;
-    pollset.active_fd.size += ERTS_ACTIVE_FD_INC;
-    pollset.active_fd.array = erts_realloc(ERTS_ALC_T_ACTIVE_FD_ARR,
-                                           pollset.active_fd.array,
-                                           pollset.active_fd.size*sizeof(ErtsSysFdType));
-#ifdef DEBUG
-    {
-        int i;
-        for (i = pollset.active_fd.eix + 1; i < pollset.active_fd.size; i++)
-            pollset.active_fd.array[i] = ERTS_SYS_FD_INVALID;
-    }
-#endif
-}
-
-static ERTS_INLINE void
-add_active_fd(ErtsSysFdType fd)
-{
-    int eix = pollset.active_fd.eix;
-    int size = pollset.active_fd.size;
-    
-    pollset.active_fd.array[eix] = fd;
-
-    erts_smp_atomic32_set_relb(&pollset.active_fd.no,
-			       (erts_smp_atomic32_read_dirty(&pollset.active_fd.no)
-				+ 1));
-
-    eix++;
-    if (eix >= size)
-	eix = 0;
-    pollset.active_fd.eix = eix;
-
-    if (pollset.active_fd.six == eix) {
-        grow_active_fds();
-    }
-}
 
 int
-ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
-			       ErlDrvEvent e,
-			       int mode,
-			       int on)
+driver_select(ErlDrvPort ix, ErlDrvEvent e, int mode, int on)
 {
     void (*stop_select_fn)(ErlDrvEvent, void*) = NULL;
     Port *prt = erts_drvport2port(ix);
     Eterm id = erts_drvport2id(ix);
     ErtsSysFdType fd = (ErtsSysFdType) e;
     ErtsPollEvents ctl_events = (ErtsPollEvents) 0;
-    ErtsPollEvents new_events, old_events;
+    ErtsPollEvents old_events;
+    ErtsPollEvents new_events;
+    ErtsPollOp ctl_op = ERTS_POLL_OP_MOD;
     ErtsDrvEventState *state;
-    int wake_poller;
+    int wake_poller = 0;
     int ret;
-#if ERTS_CIO_HAVE_DRV_EVENT
-    ErtsDrvEventDataState *free_event = NULL;
-#endif
     ErtsDrvSelectDataState *free_select = NULL;
     ErtsNifSelectDataState *free_nif = NULL;
 #ifdef USE_VM_PROBES
     DTRACE_CHARBUF(name, 64);
 #endif
+    ERTS_MSACC_PUSH_AND_SET_STATE(ERTS_MSACC_STATE_CHECK_IO);
 
-    if (prt == ERTS_INVALID_ERL_DRV_PORT)
+    if (prt == ERTS_INVALID_ERL_DRV_PORT) {
+        ERTS_MSACC_POP_STATE();
 	return -1;
+    }
 
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
+    ERTS_LC_ASSERT(erts_lc_is_port_locked(prt));
 
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    if ((unsigned)fd >= (unsigned)erts_smp_atomic_read_nob(&drv_ev_state_len)) {
-	if (fd < 0) {
-	    return -1;    
-	}
-	if (fd >= max_fds) {
-	    drv_select_large_fd_error(ix, fd, mode, on);
-	    return -1;
-	}
-	grow_drv_ev_state(fd);
+    if (!grow_drv_ev_state(fd)) {
+        if (fd > 0) drv_select_large_fd_error(ix, fd, mode, on);
+        ERTS_MSACC_POP_STATE();
+        return -1;
     }
 #endif
 
-    erts_smp_mtx_lock(fd_mtx(fd));
+    erts_mtx_lock(fd_mtx(fd));
 
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    state = &drv_ev_state[(int) fd];
-#else
-    state = hash_get_drv_ev_state(fd); /* may be NULL! */
-#endif
+    state = get_drv_ev_state(fd); /* may be NULL! */
 
-    if (!on && (mode&ERL_DRV_USE_NO_CALLBACK) == ERL_DRV_USE) {
-	if (IS_FD_UNKNOWN(state)) {
-	    /* fast track to stop_select callback */
-	    stop_select_fn = prt->drv_ptr->stop_select;
-#ifdef USE_VM_PROBES
-	    strncpy(name, prt->drv_ptr->name,
-		    sizeof(DTRACE_CHARBUF_NAME(name))-1);
-	    name[sizeof(name)-1] = '\0';
-#endif
-	    ret = 0;
-	    goto done_unknown;
-	}
-	mode |= (ERL_DRV_READ | ERL_DRV_WRITE);
-	wake_poller = 1; /* to eject fd from pollset (if needed) */
-    }
-    else wake_poller = 0;
+    DEBUG_PRINT_FD("driver_select(%T, %p, %s, %d)",
+                   state, id, fd, drvmode2str(mode), on);
 
-#ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    if (state == NULL) {
-	state = hash_new_drv_ev_state(fd);
+    if (!on) {
+        if (IS_FD_UNKNOWN(state)) {
+            if ((mode&ERL_DRV_USE_NO_CALLBACK) == ERL_DRV_USE) {
+                /* fast track to stop_select callback */
+                stop_select_fn = prt->drv_ptr->stop_select;
+        #ifdef USE_VM_PROBES
+                strncpy(name, prt->drv_ptr->name,
+                        sizeof(DTRACE_CHARBUF_NAME(name))-1);
+                name[sizeof(name)-1] = '\0';
+        #endif
+            }
+            ret = 0;
+            goto done_unknown;
+        }
+        else if ((mode&ERL_DRV_USE_NO_CALLBACK) == ERL_DRV_USE) {
+            mode |= (ERL_DRV_READ | ERL_DRV_WRITE);
+        }
     }
-#endif
+
+    state = new_drv_ev_state(state, fd);
 
     switch (state->type) {
-#if ERTS_CIO_HAVE_DRV_EVENT
-    case ERTS_EV_TYPE_DRV_EV:
-#endif
     case ERTS_EV_TYPE_NIF:
         drv_select_steal(ix, state, mode, on);
         break;
@@ -1053,7 +718,9 @@ ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
         ASSERT(state->type == ERTS_EV_TYPE_NONE);
         break;
 
-    }}
+    }
+    default: break;
+    }
 
     if (mode & ERL_DRV_READ) {
 	if (state->type == ERTS_EV_TYPE_DRV_SEL) {
@@ -1061,7 +728,7 @@ ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
 	    if (owner != id && is_not_nil(owner))
 		drv_select_steal(ix, state, mode, on);
 	}
-	ctl_events |= ERTS_POLL_EV_IN;
+        ctl_events = ERTS_POLL_EV_IN;
     }
     if (mode & ERL_DRV_WRITE) {
 	if (state->type == ERTS_EV_TYPE_DRV_SEL) {
@@ -1070,100 +737,105 @@ ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
 		drv_select_steal(ix, state, mode, on);
 	}
 	ctl_events |= ERTS_POLL_EV_OUT;
-    }	
+    }
+
 
     ASSERT((state->type == ERTS_EV_TYPE_DRV_SEL) ||
 	   (state->type == ERTS_EV_TYPE_NONE && !state->events));
 
-    if (!on && !(state->flags & ERTS_EV_FLAG_USED) 
-	&& state->events && !(state->events & ~ctl_events)) {	
-	/* Old driver removing all events. At least wake poller.
-	   It will not make close() 100% safe but it will prevent
-	   actions delayed by poll timeout. */
-	wake_poller = 1;
-    }
+    old_events = state->events;
 
-    new_events = ERTS_CIO_POLL_CTL(pollset.ps, state->fd, ctl_events, on, &wake_poller);
+    if (on) {
+        ctl_events &= ~old_events;
+        state->events |= ctl_events;
+        if (ctl_events & ERTS_POLL_EV_IN && (!state->driver.select || !is_iotask_active(&state->driver.select->iniotask)))
+            state->active_events |= ERTS_POLL_EV_IN;
+        if (ctl_events & ERTS_POLL_EV_OUT && (!state->driver.select || !is_iotask_active(&state->driver.select->outiotask)))
+            state->active_events |= ERTS_POLL_EV_OUT;
+        if (old_events == 0 && !(state->flags & ERTS_EV_FLAG_USED)) {
+            ctl_op = ERTS_POLL_OP_ADD;
+        }
+    }
+    else {
+        ctl_events &= old_events;
+        state->events &= ~ctl_events;
+        state->active_events &= ~ctl_events;
 
-    if (new_events & (ERTS_POLL_EV_ERR|ERTS_POLL_EV_NVAL)) {
-	if (state->type == ERTS_EV_TYPE_DRV_SEL && !state->events) {
-	    state->type = ERTS_EV_TYPE_NONE;
-	    state->flags &= ~ERTS_EV_FLAG_USED;
-	    state->driver.select->inport = NIL;
-	    state->driver.select->outport = NIL;
-	}
-	ret = -1;
-	goto done;
+        if (!state->events) {
+            if (!(state->flags & ERTS_EV_FLAG_USED) || mode & ERL_DRV_USE)
+                ctl_op = ERTS_POLL_OP_DEL;
+        }
     }
 
-    old_events = state->events;
+    if (ctl_events || ctl_op == ERTS_POLL_OP_DEL) {
 
-    ASSERT(on
-	   ? (new_events == (state->events | ctl_events))
-	   : (new_events == (state->events & ~ctl_events)));
+        new_events = erts_io_control_wakeup(state, ctl_op,
+                                            state->active_events,
+                                            &wake_poller);
 
-    ASSERT(state->type == ERTS_EV_TYPE_DRV_SEL
-	   || state->type == ERTS_EV_TYPE_NONE);
+        ASSERT(state->type == ERTS_EV_TYPE_DRV_SEL || state->type == ERTS_EV_TYPE_NONE);
+    }
 
-    state->events = new_events;
-    if (ctl_events) {
-	if (on) {
+    if (on) {
+        if (ctl_events) {
 	    if (!state->driver.select)
-		state->driver.select = alloc_drv_select_data();
+		state->driver.select = alloc_drv_select_data(state->fd);
 	    if (state->type == ERTS_EV_TYPE_NONE)
 		state->type = ERTS_EV_TYPE_DRV_SEL;
 	    ASSERT(state->type == ERTS_EV_TYPE_DRV_SEL);
-	    if (ctl_events & ERTS_POLL_EV_IN)
+	    if (ctl_events & ERTS_POLL_EV_IN) {
 		state->driver.select->inport = id;
-	    if (ctl_events & ERTS_POLL_EV_OUT)
+                if (new_events & (ERTS_POLL_EV_ERR|ERTS_POLL_EV_NVAL))
+                    iready(id, state);
+            }
+	    if (ctl_events & ERTS_POLL_EV_OUT) {
 		state->driver.select->outport = id;
-	    if (mode & ERL_DRV_USE) {
+                if (new_events & (ERTS_POLL_EV_ERR|ERTS_POLL_EV_NVAL))
+                    oready(id, state);
+            }
+	    if (mode & ERL_DRV_USE)
 		state->flags |= ERTS_EV_FLAG_USED;
-	    }
-	}
-	else { /* off */
-	    if (state->type == ERTS_EV_TYPE_DRV_SEL) {
-		if (ctl_events & ERTS_POLL_EV_IN) {
-		    abort_tasks(state, ERL_DRV_READ);
-		    state->driver.select->inport = NIL;
-		}
-		if (ctl_events & ERTS_POLL_EV_OUT) {
-		    abort_tasks(state, ERL_DRV_WRITE);
-		    state->driver.select->outport = NIL;
-		}
-		if (new_events == 0) {
-		    if (old_events != 0) {
-			remember_removed(state, &pollset);
-		    }		    
-		    if ((mode & ERL_DRV_USE) || !(state->flags & ERTS_EV_FLAG_USED)) {
-			state->type = ERTS_EV_TYPE_NONE;
-			state->flags &= ~ERTS_EV_FLAG_USED;
-		    }
-		    /*else keep it, as fd will probably be selected upon again */
-		}
-	    }
-	    if ((mode & ERL_DRV_USE_NO_CALLBACK) == ERL_DRV_USE) {
-		erts_driver_t* drv_ptr = prt->drv_ptr;
-		ASSERT(new_events==0);
-		if (state->remove_cnt == 0 || !wake_poller) {
-		    /* Safe to close fd now as it is not in pollset
-		       or there was no need to eject fd (kernel poll) */
-		    stop_select_fn = drv_ptr->stop_select;
+        }
+    }
+    else { /* off */
+        if (state->type == ERTS_EV_TYPE_DRV_SEL) {
+            if (ctl_events & ERTS_POLL_EV_IN) {
+                abort_tasks(state, ERL_DRV_READ);
+                state->driver.select->inport = NIL;
+            }
+            if (ctl_events & ERTS_POLL_EV_OUT) {
+                abort_tasks(state, ERL_DRV_WRITE);
+                state->driver.select->outport = NIL;
+            }
+            if (state->events == 0) {
+                if ((mode & ERL_DRV_USE) || !(state->flags & ERTS_EV_FLAG_USED)) {
+                    state->type = ERTS_EV_TYPE_NONE;
+                    state->flags = 0;
+                }
+                /*else keep it, as fd will probably be selected upon again */
+            }
+        }
+        if ((mode & ERL_DRV_USE_NO_CALLBACK) == ERL_DRV_USE) {
+            erts_driver_t* drv_ptr = prt->drv_ptr;
+            ASSERT(state->events==0);
+            if (!wake_poller) {
+                /* Safe to close fd now as it is not in pollset
+                   or there was no need to eject fd (kernel poll) */
+                stop_select_fn = drv_ptr->stop_select;
 #ifdef USE_VM_PROBES
-		    strncpy(name, prt->drv_ptr->name, sizeof(name)-1);
-		    name[sizeof(name)-1] = '\0';
+                strncpy(name, prt->drv_ptr->name, sizeof(name)-1);
+                name[sizeof(name)-1] = '\0';
 #endif
-		}
-		else {
-		    /* Not safe to close fd, postpone stop_select callback. */
-		    state->type = ERTS_EV_TYPE_STOP_USE;
-		    state->driver.stop.drv_ptr = drv_ptr;
-		    if (drv_ptr->handle) {
-			erts_ddll_reference_referenced_driver(drv_ptr->handle);
-		    }
-		}
-	    }
-	}
+            }
+            else {
+                /* Not safe to close fd, postpone stop_select callback. */
+                state->type = ERTS_EV_TYPE_STOP_USE;
+                state->driver.stop.drv_ptr = drv_ptr;
+                if (drv_ptr->handle) {
+                    erts_ddll_reference_referenced_driver(drv_ptr->handle);
+                }
+            }
+        }
     }
    
     ret = 0;
@@ -1171,14 +843,11 @@ ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
 done:
 
     check_fd_cleanup(state,
-#if ERTS_CIO_HAVE_DRV_EVENT
-		     &free_event,
-#endif
 		     &free_select,
                      &free_nif);
 
 done_unknown:
-    erts_smp_mtx_unlock(fd_mtx(fd));
+    erts_mtx_unlock(fd_mtx(fd));
     if (stop_select_fn) {
 	int was_unmasked = erts_block_fpe();
 	DTRACE1(driver_stop_select, name);
@@ -1191,61 +860,47 @@ done_unknown:
     if (free_nif)
         free_nif_select_data(free_nif);
 
-#if ERTS_CIO_HAVE_DRV_EVENT
-    if (free_event)
-	free_drv_event_data(free_event);
-#endif
+    ERTS_MSACC_POP_STATE();
+
     return ret;
 }
 
 int
-ERTS_CIO_EXPORT(enif_select)(ErlNifEnv* env,
-                             ErlNifEvent e,
-                             enum ErlNifSelectFlags mode,
-                             void* obj,
-                             const ErlNifPid* pid,
-                             Eterm ref)
+enif_select(ErlNifEnv* env,
+            ErlNifEvent e,
+            enum ErlNifSelectFlags mode,
+            void* obj,
+            const ErlNifPid* pid,
+            Eterm ref)
 {
     int on;
     ErtsResource* resource = DATA_TO_RESOURCE(obj);
     ErtsSysFdType fd = (ErtsSysFdType) e;
     ErtsPollEvents ctl_events = (ErtsPollEvents) 0;
-    ErtsPollEvents new_events, old_events;
+    ErtsPollEvents old_events;
+    ErtsPollOp ctl_op = ERTS_POLL_OP_MOD;
     ErtsDrvEventState *state;
-    int wake_poller;
-    int ret;
+    int ret, wake_poller = 0;
     enum { NO_STOP=0, CALL_STOP, CALL_STOP_AND_RELEASE } call_stop = NO_STOP;
-#if ERTS_CIO_HAVE_DRV_EVENT
-    ErtsDrvEventDataState *free_event = NULL;
-#endif
     ErtsDrvSelectDataState *free_select = NULL;
     ErtsNifSelectDataState *free_nif = NULL;
-#ifdef USE_VM_PROBES
-    DTRACE_CHARBUF(name, 64);
-#endif
 
     ASSERT(!(resource->monitors && resource->monitors->is_dying));
 
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    if ((unsigned)fd >= (unsigned)erts_smp_atomic_read_nob(&drv_ev_state_len)) {
-	if (fd < 0) {
-	    return INT_MIN | ERL_NIF_SELECT_INVALID_EVENT;
-	}
-	if (fd >= max_fds) {
-	    nif_select_large_fd_error(fd, mode, resource, ref);
-            return INT_MIN | ERL_NIF_SELECT_INVALID_EVENT;
-	}
-	grow_drv_ev_state(fd);
+    if (!grow_drv_ev_state(fd)) {
+        if (fd > 0) nif_select_large_fd_error(fd, mode, resource, ref);
+        return INT_MIN | ERL_NIF_SELECT_INVALID_EVENT;
     }
 #endif
 
-    erts_smp_mtx_lock(fd_mtx(fd));
+    erts_mtx_lock(fd_mtx(fd));
 
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    state = &drv_ev_state[(int) fd];
-#else
-    state = hash_get_drv_ev_state(fd); /* may be NULL! */
-#endif
+    state = get_drv_ev_state(fd); /* may be NULL! */
+
+    DEBUG_PRINT_FD("enif_select(%T, %d, %s, %p, %T, %T)",
+                   state, env->proc->common.id, fd, nifmode2str(mode), resource,
+                   pid ? pid->pid : THE_NON_VALUE, ref);
 
     if (mode & ERL_NIF_SELECT_STOP) {
         ASSERT(resource->type->stop);
@@ -1257,13 +912,12 @@ ERTS_CIO_EXPORT(enif_select)(ErlNifEnv* env,
         }
         on = 0;
         mode = ERL_DRV_READ | ERL_DRV_WRITE | ERL_DRV_USE;
-        wake_poller = 1; /* to eject fd from pollset (if needed) */
         ctl_events = ERTS_POLL_EV_IN | ERTS_POLL_EV_OUT;
+        ctl_op = ERTS_POLL_OP_DEL;
     }
     else {
         on = 1;
         ASSERT(mode);
-        wake_poller = 0;
         if (mode & ERL_DRV_READ) {
             ctl_events |= ERTS_POLL_EV_IN;
         }
@@ -1272,11 +926,7 @@ ERTS_CIO_EXPORT(enif_select)(ErlNifEnv* env,
         }
     }
 
-#ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    if (state == NULL) {
-	state = hash_new_drv_ev_state(fd);
-    }
-#endif
+    state = new_drv_ev_state(state,fd);
 
     switch (state->type) {
     case ERTS_EV_TYPE_NIF:
@@ -1287,9 +937,6 @@ ERTS_CIO_EXPORT(enif_select)(ErlNifEnv* env,
         if (state->driver.stop.resource != resource)
             nif_select_steal(state, ERL_DRV_READ | ERL_DRV_WRITE, resource, ref);
         break;
-#if ERTS_CIO_HAVE_DRV_EVENT
-    case ERTS_EV_TYPE_DRV_EV:
-#endif
     case ERTS_EV_TYPE_DRV_SEL:
         nif_select_steal(state, mode, resource, ref);
         break;
@@ -1310,37 +957,52 @@ ERTS_CIO_EXPORT(enif_select)(ErlNifEnv* env,
         }
         ASSERT(state->type == ERTS_EV_TYPE_NONE);
         break;
-    }}
+    }
+    default: break;
+    }
 
     ASSERT((state->type == ERTS_EV_TYPE_NIF) ||
 	   (state->type == ERTS_EV_TYPE_NONE && !state->events));
 
-    new_events = ERTS_CIO_POLL_CTL(pollset.ps, state->fd, ctl_events, on, &wake_poller);
+    old_events = state->events;
 
-    if (new_events & (ERTS_POLL_EV_ERR|ERTS_POLL_EV_NVAL)) {
-	if (state->type == ERTS_EV_TYPE_NIF && !state->events) {
-	    state->type = ERTS_EV_TYPE_NONE;
-	    state->flags &= ~ERTS_EV_FLAG_USED;
-	    state->driver.nif->in.pid = NIL;
-	    state->driver.nif->out.pid = NIL;
-            state->driver.nif->in.ddeselect_cnt = 0;
-            state->driver.nif->out.ddeselect_cnt = 0;
-            state->driver.stop.resource = NULL;
-	}
-	ret = INT_MIN | ERL_NIF_SELECT_FAILED;
-	goto done;
+    if (on) {
+        ctl_events &= ~old_events;
+        state->events |= ctl_events;
+        state->active_events |= ctl_events;
+        if (state->type == ERTS_EV_TYPE_NONE)
+            ctl_op = ERTS_POLL_OP_ADD;
+    }
+    else {
+        ctl_events &= old_events;
+        state->events &= ~ctl_events;
+        state->active_events &= ~ctl_events;
     }
 
-    old_events = state->events;
+    if (ctl_events || ctl_op == ERTS_POLL_OP_DEL) {
+        ErtsPollEvents new_events;
+
+        new_events = erts_io_control_wakeup(state, ctl_op,
+                                            state->active_events,
+                                            &wake_poller);
 
-    ASSERT(on
-	   ? (new_events == (state->events | ctl_events))
-	   : (new_events == (state->events & ~ctl_events)));
+        if (new_events & (ERTS_POLL_EV_ERR|ERTS_POLL_EV_NVAL)) {
+            if (state->type == ERTS_EV_TYPE_NIF && !old_events) {
+                state->type = ERTS_EV_TYPE_NONE;
+                state->flags = 0;
+                state->driver.nif->in.pid = NIL;
+                state->driver.nif->out.pid = NIL;
+                state->driver.stop.resource = NULL;
+            }
+            ret = INT_MIN | ERL_NIF_SELECT_FAILED;
+            goto done;
+        }
+        ASSERT(new_events == state->events);
+    }
 
     ASSERT(state->type == ERTS_EV_TYPE_NIF
 	   || state->type == ERTS_EV_TYPE_NONE);
 
-    state->events = new_events;
     if (on) {
         const Eterm recipient = pid ? pid->pid : env->proc->common.id;
         Uint32* refn;
@@ -1353,7 +1015,7 @@ ERTS_CIO_EXPORT(enif_select)(ErlNifEnv* env,
         }
         ASSERT(state->type == ERTS_EV_TYPE_NIF);
         ASSERT(state->driver.stop.resource == resource);
-        if (ctl_events & ERTS_POLL_EV_IN) {
+        if (mode & ERL_DRV_READ) {
             state->driver.nif->in.pid = recipient;
             if (is_immed(ref)) {
                 state->driver.nif->in.immed = ref;
@@ -1361,13 +1023,11 @@ ERTS_CIO_EXPORT(enif_select)(ErlNifEnv* env,
                 ASSERT(is_internal_ref(ref));
                 refn = internal_ref_numbers(ref);
                 state->driver.nif->in.immed = THE_NON_VALUE;
-                state->driver.nif->in.refn[0] = refn[0];
-                state->driver.nif->in.refn[1] = refn[1];
-                state->driver.nif->in.refn[2] = refn[2];
+                sys_memcpy(state->driver.nif->in.refn, refn,
+                           sizeof(state->driver.nif->in.refn));
             }
-            state->driver.nif->in.ddeselect_cnt = 0;
         }
-        if (ctl_events & ERTS_POLL_EV_OUT) {
+        if (mode & ERL_DRV_WRITE) {
             state->driver.nif->out.pid = recipient;
             if (is_immed(ref)) {
                 state->driver.nif->out.immed = ref;
@@ -1375,11 +1035,9 @@ ERTS_CIO_EXPORT(enif_select)(ErlNifEnv* env,
                 ASSERT(is_internal_ref(ref));
                 refn = internal_ref_numbers(ref);
                 state->driver.nif->out.immed = THE_NON_VALUE;
-                state->driver.nif->out.refn[0] = refn[0];
-                state->driver.nif->out.refn[1] = refn[1];
-                state->driver.nif->out.refn[2] = refn[2];
+                sys_memcpy(state->driver.nif->out.refn, refn,
+                           sizeof(state->driver.nif->out.refn));
             }
-            state->driver.nif->out.ddeselect_cnt = 0;
         }
         ret = 0;
     }
@@ -1387,14 +1045,9 @@ ERTS_CIO_EXPORT(enif_select)(ErlNifEnv* env,
         if (state->type == ERTS_EV_TYPE_NIF) {
             state->driver.nif->in.pid = NIL;
             state->driver.nif->out.pid = NIL;
-            state->driver.nif->in.ddeselect_cnt = 0;
-            state->driver.nif->out.ddeselect_cnt = 0;
-            if (old_events != 0) {
-                remember_removed(state, &pollset);
-            }
         }
-        ASSERT(new_events==0);
-        if (state->remove_cnt == 0 || !wake_poller) {
+        ASSERT(state->events==0);
+        if (!wake_poller) {
             /*
              * Safe to close fd now as it is not in pollset
              * or there was no need to eject fd (kernel poll)
@@ -1426,14 +1079,11 @@ ERTS_CIO_EXPORT(enif_select)(ErlNifEnv* env,
 done:
 
     check_fd_cleanup(state,
-#if ERTS_CIO_HAVE_DRV_EVENT
-		     &free_event,
-#endif
 		     &free_select,
                      &free_nif);
 
 done_unknown:
-    erts_smp_mtx_unlock(fd_mtx(fd));
+    erts_mtx_unlock(fd_mtx(fd));
     if (call_stop) {
         erts_resource_stop(resource, (ErlNifEvent)fd, 1);
         if (call_stop == CALL_STOP_AND_RELEASE) {
@@ -1445,162 +1095,9 @@ done_unknown:
     if (free_nif)
         free_nif_select_data(free_nif);
 
-#if ERTS_CIO_HAVE_DRV_EVENT
-    if (free_event)
-	free_drv_event_data(free_event);
-#endif
     return ret;
 }
 
-
-int
-ERTS_CIO_EXPORT(driver_event)(ErlDrvPort ix,
-			      ErlDrvEvent e,
-			      ErlDrvEventData event_data)
-{
-#if !ERTS_CIO_HAVE_DRV_EVENT
-    return -1;
-#else
-    ErtsSysFdType fd = (ErtsSysFdType) e;
-    ErtsPollEvents events;
-    ErtsPollEvents add_events;
-    ErtsPollEvents remove_events;
-    Eterm id = erts_drvport2id(ix);
-    ErtsDrvEventState *state;
-    int do_wake = 0;
-    int ret;
-#if ERTS_CIO_HAVE_DRV_EVENT
-    ErtsDrvEventDataState *free_event;
-#endif
-    ErtsDrvSelectDataState *free_select;
-    ErtsNifSelectDataState *free_nif;
-    Port *prt = erts_drvport2port(ix);
-
-    if (prt == ERTS_INVALID_ERL_DRV_PORT)
-	return -1;
-
-    ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
-
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    if ((unsigned)fd >= (unsigned)erts_smp_atomic_read_nob(&drv_ev_state_len)) {
-	if (fd < 0)
-	    return -1;    
-	if (fd >= max_fds) {
-	    event_large_fd_error(ix, fd, event_data);
-	    return -1;
-	}
-	grow_drv_ev_state(fd);
-    }
-#endif
-
-    erts_smp_mtx_lock(fd_mtx(fd));
-
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    state = &drv_ev_state[(int) fd];
-#else
-    /* Could use hash_new directly, but want to keep the normal case fast */
-    state = hash_get_drv_ev_state(fd);
-    if (state == NULL) {
-	state = hash_new_drv_ev_state(fd);
-    }
-#endif
-
-    switch (state->type) {
-    case ERTS_EV_TYPE_DRV_EV:
-	if (state->driver.event->port == id) break;
-	/*fall through*/
-    case ERTS_EV_TYPE_DRV_SEL:
-	drv_event_steal(ix, state, event_data);
-	break;
-    case ERTS_EV_TYPE_STOP_USE: {
-	erts_dsprintf_buf_t *dsbufp = erts_create_logger_dsbuf();
-	print_drv_event_op(dsbufp, ix, fd, event_data);
-	steal_pending_stop_use(dsbufp, ix, state, 0, 1);
-	break;
-      }
-    }
-
-    ASSERT(state->type == ERTS_EV_TYPE_DRV_EV
-	   || state->type == ERTS_EV_TYPE_NONE);
-
-    events = state->events;
-
-    if (!event_data) {
-	remove_events = events;
-	add_events = 0;
-    }
-    else {
-	remove_events = ~event_data->events & events;
-	add_events = ~events & event_data->events;
-    }
-
-    if (add_events) {
-	events = ERTS_CIO_POLL_CTL(pollset.ps, state->fd, add_events, 1, &do_wake);
-	if (events & (ERTS_POLL_EV_ERR|ERTS_POLL_EV_NVAL)) {
-	    ret = -1;
-	    goto done;
-	}
-    }
-    if (remove_events) {
-	events = ERTS_CIO_POLL_CTL(pollset.ps, state->fd, remove_events, 0, &do_wake);
-	if (events & (ERTS_POLL_EV_ERR|ERTS_POLL_EV_NVAL)) {
-	    ret = -1;
-	    goto done;
-	}
-    }
-    if (event_data && event_data->events != 0) {
-	if (state->type == ERTS_EV_TYPE_DRV_EV) {
-	    state->driver.event->removed_events &= ~add_events;
-	    state->driver.event->removed_events |= remove_events;
-	}
-	else {
-	    if (!state->driver.event)
-		state->driver.event = alloc_drv_event_data();
-	    state->driver.event->port = id;
-	    state->driver.event->removed_events = (ErtsPollEvents) 0;
-	    state->type = ERTS_EV_TYPE_DRV_EV;
-	}
-	state->driver.event->data = event_data;
-    }
-    else {
-	if (state->type == ERTS_EV_TYPE_DRV_EV) {
-	    abort_tasks(state, 0);
-	    state->driver.event->port = NIL;
-	    state->driver.event->data = NULL;
-	    state->driver.event->removed_events = (ErtsPollEvents) 0;
-	}
-	state->type = ERTS_EV_TYPE_NONE;
-	remember_removed(state, &pollset);
-    }
-    state->events = events;
-    ASSERT(event_data ? events == event_data->events : events == 0); 
-
-    ret = 0;
-
-done:
-
-    check_fd_cleanup(state,
-#if ERTS_CIO_HAVE_DRV_EVENT
-		     &free_event,
-#endif
-		     &free_select,
-                     &free_nif);
-
-    erts_smp_mtx_unlock(fd_mtx(fd));
-
-    if (free_select)
-	free_drv_select_data(free_select);
-    if (free_nif)
-        free_nif_select_data(free_nif);
-#if ERTS_CIO_HAVE_DRV_EVENT
-    if (free_event)
-	free_drv_event_data(free_event);
-#endif
-
-    return ret;
-#endif
-}
-
 static ERTS_INLINE int
 chk_stale(Eterm id, ErtsDrvEventState *state, int mode)
 {
@@ -1632,11 +1129,6 @@ need2steal(ErtsDrvEventState *state, int mode)
         do_steal = 1;
         break;
 
-#if ERTS_CIO_HAVE_DRV_EVENT
-    case ERTS_EV_TYPE_DRV_EV:
-	do_steal |= chk_stale(state->driver.event->port, state, 0);
-	break;
-#endif
     case ERTS_EV_TYPE_STOP_USE:
     case ERTS_EV_TYPE_STOP_NIF:
         ASSERT(0);
@@ -1670,7 +1162,7 @@ print_driver_name(erts_dsprintf_buf_t *dsbufp, Eterm id)
 static void
 steal(erts_dsprintf_buf_t *dsbufp, ErtsDrvEventState *state, int mode)
 {
-    erts_dsprintf(dsbufp, "stealing control of fd=%d from ", (int) GET_FD(state->fd));
+    erts_dsprintf(dsbufp, "stealing control of fd=%d from ", (int) state->fd);
     switch (state->type) {
     case ERTS_EV_TYPE_DRV_SEL: {
 	int deselect_mode = 0;
@@ -1694,7 +1186,7 @@ steal(erts_dsprintf_buf_t *dsbufp, ErtsDrvEventState *state, int mode)
 	if (deselect_mode)
 	    deselect(state, deselect_mode);
 	else {
-	    erts_dsprintf(dsbufp, "no one", (int) GET_FD(state->fd));
+	    erts_dsprintf(dsbufp, "no one", (int) state->fd);
 	    ASSERT(0);
 	}
 	erts_dsprintf(dsbufp, "\n");
@@ -1719,30 +1211,13 @@ steal(erts_dsprintf_buf_t *dsbufp, ErtsDrvEventState *state, int mode)
         erts_dsprintf(dsbufp, "\n");
         break;
     }
-#if ERTS_CIO_HAVE_DRV_EVENT
-    case ERTS_EV_TYPE_DRV_EV: {
-	Eterm eid = state->driver.event->port;
-	if (is_nil(eid)) {
-	    erts_dsprintf(dsbufp, "no one", (int) state->fd);
-	    ASSERT(0);
-	}
-	else {
-	    erts_dsprintf(dsbufp, "event driver ");
-	    print_driver_name(dsbufp, eid);
-	    erts_dsprintf(dsbufp, "%T ", eid);
-	}
-	erts_dsprintf(dsbufp, "\n");
-	deselect(state, 0);
-	break;
-    }
-#endif
     case ERTS_EV_TYPE_STOP_USE:
     case ERTS_EV_TYPE_STOP_NIF: {
 	ASSERT(0);
 	break;
     }
     default:
-	erts_dsprintf(dsbufp, "no one\n", (int) GET_FD(state->fd));
+	erts_dsprintf(dsbufp, "no one\n", (int) state->fd);
 	ASSERT(0);
     }
 }
@@ -1756,7 +1231,7 @@ print_drv_select_op(erts_dsprintf_buf_t *dsbufp,
 		  "driver_select(%p, %d,%s%s%s%s, %d) "
 		  "by ",
 		  ix,
-		  (int) GET_FD(fd),
+		  (int) fd,
 		  mode & ERL_DRV_READ ? " ERL_DRV_READ" : "",
 		  mode & ERL_DRV_WRITE ? " ERL_DRV_WRITE" : "",
 		  mode & ERL_DRV_USE ? " ERL_DRV_USE" : "",
@@ -1773,7 +1248,7 @@ print_nif_select_op(erts_dsprintf_buf_t *dsbufp,
 {
     erts_dsprintf(dsbufp,
 		  "enif_select(_, %d,%s%s%s, %T:%T, %T) ",
-		  (int) GET_FD(fd),
+		  (int) fd,
 		  mode & ERL_NIF_SELECT_READ ? " READ" : "",
 		  mode & ERL_NIF_SELECT_WRITE ? " WRITE" : "",
 		  mode & ERL_NIF_SELECT_STOP ? " STOP" : "",
@@ -1812,7 +1287,7 @@ large_fd_error_common(erts_dsprintf_buf_t *dsbufp, ErtsSysFdType fd)
 {
     erts_dsprintf(dsbufp,
 		  "fd=%d is larger than the largest allowed fd=%d\n",
-		  (int) fd, max_fds - 1);
+		  (int) fd, drv_ev_state.max_fds - 1);
 }
 
 static void
@@ -1868,7 +1343,7 @@ steal_pending_stop_use(erts_dsprintf_buf_t *dsbufp, ErlDrvPort ix,
             erts_ddll_dereference_driver(state->driver.stop.drv_ptr->handle);
         }
         state->type = ERTS_EV_TYPE_NONE;
-        state->flags &= ~ERTS_EV_FLAG_USED;
+        state->flags = 0;
         state->driver.stop.drv_ptr = NULL;
     }
     else {
@@ -1905,9 +1380,9 @@ steal_pending_stop_nif(erts_dsprintf_buf_t *dsbufp, ErtsResource* resource,
         erts_dsprintf(dsbufp, "called before stop was called for NIF resource %T:%T\n",
                       rt->module, rt->name);
 
-        enif_release_resource(state->driver.stop.resource);
+        enif_release_resource(state->driver.stop.resource->data);
         state->type = ERTS_EV_TYPE_NONE;
-        state->flags &= ~ERTS_EV_FLAG_USED;
+        state->flags = 0;
         state->driver.stop.resource = NULL;
     }
     else {
@@ -1917,59 +1392,9 @@ steal_pending_stop_nif(erts_dsprintf_buf_t *dsbufp, ErtsResource* resource,
 
 }
 
-
-#if ERTS_CIO_HAVE_DRV_EVENT
-
-static void
-print_drv_event_op(erts_dsprintf_buf_t *dsbufp,
-                   ErlDrvPort ix, ErtsSysFdType fd, ErlDrvEventData event_data)
-{
-    Port *pp = erts_drvport2port(ix);
-    erts_dsprintf(dsbufp, "driver_event(%p, %d, ", ix, (int) fd);
-    if (!event_data)
-	erts_dsprintf(dsbufp, "NULL");
-    else
-	erts_dsprintf(dsbufp, "{0x%x, 0x%x}",
-		      (unsigned int) event_data->events,
-		      (unsigned int) event_data->revents);
-    erts_dsprintf(dsbufp, ") by ");
-    if (pp != ERTS_INVALID_ERL_DRV_PORT)
-	print_driver_name(dsbufp, pp->common.id);
-    erts_dsprintf(dsbufp, "driver %T ", pp != ERTS_INVALID_ERL_DRV_PORT ? pp->common.id : NIL);
-}
-
-static void
-drv_event_steal(ErlDrvPort ix, ErtsDrvEventState *state, ErlDrvEventData event_data)
-{
-    if (need2steal(state, ERL_DRV_READ|ERL_DRV_WRITE)) {
-	erts_dsprintf_buf_t *dsbufp = erts_create_logger_dsbuf();
-	print_drv_event_op(dsbufp, ix, state->fd, event_data);
-	steal(dsbufp, state, ERL_DRV_READ|ERL_DRV_WRITE);
-	erts_send_error_to_logger_nogl(dsbufp);
-    }
-    else if (state->type == ERTS_EV_TYPE_DRV_SEL) {
-	ASSERT(state->flags & ERTS_EV_FLAG_USED);
-	deselect(state, 0);
-    }
-}
-
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-static void
-event_large_fd_error(ErlDrvPort ix, ErtsSysFdType fd, ErlDrvEventData event_data)
-{
-    erts_dsprintf_buf_t *dsbufp = erts_create_logger_dsbuf();
-    print_drv_event_op(dsbufp, ix, fd, event_data);
-    erts_dsprintf(dsbufp, "failed: ");
-    large_fd_error_common(dsbufp, fd);
-    erts_send_error_to_logger_nogl(dsbufp);
-}
-#endif
-#endif
-
 static ERTS_INLINE int
 io_task_schedule_allowed(ErtsDrvEventState *state,
-			 ErtsPortTaskType type,
-			 erts_aint_t current_cio_time)
+			 ErtsPortTaskType type)
 {
     ErtsIoTask *io_task;
 
@@ -1977,71 +1402,53 @@ io_task_schedule_allowed(ErtsDrvEventState *state,
     case ERTS_PORT_TASK_INPUT:
 	if (!state->driver.select)
 	    return 0;
-#if ERTS_CIO_HAVE_DRV_EVENT
-	if (state->driver.event)
-	    return 0;
-#endif
 	io_task = &state->driver.select->iniotask;
 	break;
     case ERTS_PORT_TASK_OUTPUT:
 	if (!state->driver.select)
 	    return 0;
-#if ERTS_CIO_HAVE_DRV_EVENT
-	if (state->driver.event)
-	    return 0;
-#endif
 	io_task = &state->driver.select->outiotask;
 	break;
-#if ERTS_CIO_HAVE_DRV_EVENT
-    case ERTS_PORT_TASK_EVENT:
-	if (!state->driver.event)
-	    return 0;
-	if (state->driver.select)
-	    return 0;
-	io_task = &state->driver.event->iotask;
-	break;
-#endif
     default:
 	ERTS_INTERNAL_ERROR("Invalid I/O-task type");
 	return 0;
     }
 
-    return !is_iotask_active(io_task, current_cio_time);
+    return !is_iotask_active(io_task);
 }
 
 static ERTS_INLINE void
-iready(Eterm id, ErtsDrvEventState *state, erts_aint_t current_cio_time)
+iready(Eterm id, ErtsDrvEventState *state)
 {
     if (io_task_schedule_allowed(state,
-				 ERTS_PORT_TASK_INPUT,
-				 current_cio_time)) {
+				 ERTS_PORT_TASK_INPUT)) {
 	ErtsIoTask *iotask = &state->driver.select->iniotask;
-	erts_smp_atomic_set_nob(&iotask->executed_time, current_cio_time);
 	if (erts_port_task_schedule(id,
 				    &iotask->task,
 				    ERTS_PORT_TASK_INPUT,
 				    (ErlDrvEvent) state->fd) != 0) {
 	    stale_drv_select(id, state, ERL_DRV_READ);
-	}
-	add_active_fd(state->fd);
+	} else {
+            DEBUG_PRINT_FD("schedule ready_input(%T, %d)",
+                           state, id, state->fd);
+        }
     }
 }
 
 static ERTS_INLINE void
-oready(Eterm id, ErtsDrvEventState *state, erts_aint_t current_cio_time)
+oready(Eterm id, ErtsDrvEventState *state)
 {
     if (io_task_schedule_allowed(state,
-				 ERTS_PORT_TASK_OUTPUT,
-				 current_cio_time)) {
+				 ERTS_PORT_TASK_OUTPUT)) {
 	ErtsIoTask *iotask = &state->driver.select->outiotask;
-	erts_smp_atomic_set_nob(&iotask->executed_time, current_cio_time);
 	if (erts_port_task_schedule(id,
 				    &iotask->task,
 				    ERTS_PORT_TASK_OUTPUT,
 				    (ErlDrvEvent) state->fd) != 0) {
 	    stale_drv_select(id, state, ERL_DRV_WRITE);
-	}
-	add_active_fd(state->fd);
+	} else {
+            DEBUG_PRINT_FD("schedule ready_output(%T, %d)", state, id, state->fd);
+        }
     }
 }
 
@@ -2090,141 +1497,62 @@ send_event_tuple(struct erts_nif_select_event* e, ErtsResource* resource,
     erts_queue_message(rp, rp_locks, mp, tuple, am_system);
 
     if (rp_locks)
-        erts_smp_proc_unlock(rp, rp_locks);
+        erts_proc_unlock(rp, rp_locks);
 }
 
-
-#if ERTS_CIO_HAVE_DRV_EVENT
-static ERTS_INLINE void
-eready(Eterm id, ErtsDrvEventState *state, ErlDrvEventData event_data,
-       erts_aint_t current_cio_time)
-{
-    if (io_task_schedule_allowed(state,
-				 ERTS_PORT_TASK_EVENT,
-				 current_cio_time)) {
-	ErtsIoTask *iotask = &state->driver.event->iotask;
-	erts_smp_atomic_set_nob(&iotask->executed_time, current_cio_time);
-	if (erts_port_task_schedule(id,
-				    &iotask->task,
-				    ERTS_PORT_TASK_EVENT,
-				    (ErlDrvEvent) state->fd,
-				    event_data) != 0) {
-	    stale_drv_select(id, state, 0);
-	}
-	add_active_fd(state->fd);
-    }
-}
-#endif
-
 static void bad_fd_in_pollset(ErtsDrvEventState *, Eterm inport, Eterm outport);
 
-#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
 void
-ERTS_CIO_EXPORT(erts_check_io_async_sig_interrupt)(void)
+erts_check_io_interrupt(ErtsPollThread *psi, int set)
 {
-    ERTS_CIO_POLL_AS_INTR(pollset.ps);
-}
+    if (psi) {
+#if ERTS_POLL_USE_FALLBACK
+        if (psi->ps == get_fallback()) {
+            erts_poll_interrupt_flbk(psi->ps, set);
+            return;
+        }
 #endif
-
-void
-ERTS_CIO_EXPORT(erts_check_io_interrupt)(int set)
-{
-    ERTS_CIO_POLL_INTR(pollset.ps, set);
+        erts_poll_interrupt(psi->ps, set);
+    }
 }
 
-void
-ERTS_CIO_EXPORT(erts_check_io_interrupt_timed)(int set,
-					       ErtsMonotonicTime timeout_time)
-{
-    ERTS_CIO_POLL_INTR_TMD(pollset.ps, set, timeout_time);
+ErtsPollThread *
+erts_create_pollset_thread(int id) {
+    return psiv+id;
 }
 
-#if !ERTS_CIO_DEFER_ACTIVE_EVENTS
-/*
- * Number of ignored events, for a lingering fd added by enif_select(),
- * until we deselect fd-event from pollset.
- */
-# define ERTS_NIF_DELAYED_DESELECT 20
-#else
-/* Disable delayed deselect as pollset cannot handle active events */
-# define ERTS_NIF_DELAYED_DESELECT 1
-#endif
-
 void
-ERTS_CIO_EXPORT(erts_check_io)(int do_wait)
+erts_check_io(ErtsPollThread *psi)
 {
-    ErtsPollResFd *pollres;
     int pollres_len;
-    ErtsMonotonicTime timeout_time;
     int poll_ret, i;
-    erts_aint_t current_cio_time;
-    ErtsSchedulerData *esdp = erts_get_scheduler_data();
-
-    ASSERT(esdp);
+    ERTS_MSACC_PUSH_AND_SET_STATE(ERTS_MSACC_STATE_CHECK_IO);
 
  restart:
 
-#ifdef ERTS_BREAK_REQUESTED
-    if (ERTS_BREAK_REQUESTED)
-	erts_do_break_handling();
-#endif
-
-#ifdef ERTS_SIGNAL_STATE /* ifndef ERTS_SMP */
-    if (ERTS_SIGNAL_STATE) {
-        erts_handle_signal_state();
-    }
-#endif
-
-    /* Figure out timeout value */
-    timeout_time = (do_wait
-		    ? erts_check_next_timeout_time(esdp)
-		    : ERTS_POLL_NO_TIMEOUT /* poll only */);
-
-    /*
-     * No need for an atomic inc op when incrementing
-     * erts_check_io_time, since only one thread can
-     * check io at a time.
-     */
-    current_cio_time = erts_smp_atomic_read_dirty(&erts_check_io_time);
-    current_cio_time++;
-    erts_smp_atomic_set_relb(&erts_check_io_time, current_cio_time);
-
-    check_cleanup_active_fds(current_cio_time,
-                             timeout_time != ERTS_POLL_NO_TIMEOUT);
-
 #ifdef ERTS_ENABLE_LOCK_CHECK
     erts_lc_check_exact(NULL, 0); /* No locks should be locked */
 #endif
 
-    pollres_len = erts_smp_atomic32_read_dirty(&pollset.active_fd.no) + ERTS_CHECK_IO_POLL_RES_LEN;
+    pollres_len = psi->pollres_len;
 
-    pollres = erts_alloc(ERTS_ALC_T_TMP, sizeof(ErtsPollResFd)*pollres_len);
+#if ERTS_POLL_USE_FALLBACK
+    if (psi->ps == get_fallback()) {
 
-    erts_smp_atomic_set_nob(&pollset.in_poll_wait, 1);
+        poll_ret = erts_poll_wait_flbk(psi->ps, psi->pollres, &pollres_len);
 
-    poll_ret = ERTS_CIO_POLL_WAIT(pollset.ps, pollres, &pollres_len, timeout_time);
+    } else
+#endif
+    {
+        poll_ret = erts_poll_wait(psi->ps, psi->pollres, &pollres_len);
+    }
 
 #ifdef ERTS_ENABLE_LOCK_CHECK
     erts_lc_check_exact(NULL, 0); /* No locks should be locked */
 #endif
 
-#ifdef ERTS_BREAK_REQUESTED
-    if (ERTS_BREAK_REQUESTED)
-	erts_do_break_handling();
-#endif
-
-
-#ifdef ERTS_SIGNAL_STATE /* ifndef ERTS_SMP */
-    if (ERTS_SIGNAL_STATE) {
-        erts_handle_signal_state();
-    }
-#endif
-
-
     if (poll_ret != 0) {
-	erts_smp_atomic_set_nob(&pollset.in_poll_wait, 0);
-	forget_removed(&pollset);
-	erts_free(ERTS_ALC_T_TMP, pollres);
+
 	if (poll_ret == EAGAIN) {
 	    goto restart;
 	}
@@ -2240,65 +1568,86 @@ ERTS_CIO_EXPORT(erts_check_io)(int do_wait)
 			  erl_errno_id(poll_ret), poll_ret);
 	    erts_send_error_to_logger_nogl(dsbufp);
 	}
+        ERTS_MSACC_POP_STATE();
 	return;
     }
 
     for (i = 0; i < pollres_len; i++) {
 
-	ErtsSysFdType fd = (ErtsSysFdType) pollres[i].fd;
+        erts_driver_t* drv_ptr = NULL;
+        ErtsResource* resource = NULL;
+        ErtsDrvSelectDataState *free_select = NULL;
+        ErtsNifSelectDataState *free_nif = NULL;
+	ErtsSysFdType fd = (ErtsSysFdType) ERTS_POLL_RES_GET_FD(&psi->pollres[i]);
 	ErtsDrvEventState *state;
+        ErtsPollEvents revents;
 
-	erts_smp_mtx_lock(fd_mtx(fd));
+	erts_mtx_lock(fd_mtx(fd));
+
+	state = get_drv_ev_state(fd);
 
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-	state = &drv_ev_state[ (int) fd];
-#else
-	state = hash_get_drv_ev_state(fd);
 	if (!state) {
-	    goto next_pollres;
+            erts_mtx_unlock(fd_mtx(fd));
+            continue;
 	}
-#endif
 
-	/* Skip this fd if it was removed from pollset */
-	if (is_removed(state)) {
-	    goto next_pollres;
-	}
+        revents = ERTS_POLL_RES_GET_EVTS(&psi->pollres[i]);
+
+        DEBUG_PRINT_FD("triggered %s", state, ev2str(revents));
+
+        if (revents & ERTS_POLL_EV_ERR) {
+            /*
+             * Handle error events by triggering all in/out events
+             * that has been selected on.
+             * We *do not* want to call a callback that corresponds
+             * to an event not selected.
+             */
+            revents = state->active_events;
+            state->active_events = 0;
+        } else {
+
+            /* Disregard any events that are not active at the moment,
+               for instance this could happen if the driver/nif does
+               select/deselect in rapid succession. */
+            revents &= state->active_events | ERTS_POLL_EV_NVAL;
+            state->active_events &= ~revents;
+
+            /* Reactivate the poll op if there are still active events */
+            if (state->active_events) {
+                ErtsPollEvents new_events;
+                DEBUG_PRINT_FD("re-enable %s", state, ev2str(state->active_events));
+
+                new_events = erts_io_control(state, ERTS_POLL_OP_MOD, state->active_events);
+
+                /* Unable to re-enable the fd, signal all callbacks */
+                if (new_events & (ERTS_POLL_EV_ERR|ERTS_POLL_EV_NVAL)) {
+                    revents |= state->active_events;
+                    state->active_events = 0;
+                }
+            }
+        }
 
 	switch (state->type) {
 	case ERTS_EV_TYPE_DRV_SEL: { /* Requested via driver_select()... */
-	    ErtsPollEvents revents = pollres[i].events;
-
-            if (revents & ERTS_POLL_EV_ERR) {
-                /*
-                 * Handle error events by triggering all in/out events
-                 * that the driver has selected.
-                 * We *do not* want to call a callback that corresponds
-		 * to an event not selected.
-                 */
-                revents = state->events;
-            }
-            else {
-                revents &= (state->events | ERTS_POLL_EV_NVAL);
-            }
 
             if (revents & (ERTS_POLL_EV_IN|ERTS_POLL_EV_OUT)) {
 		if (revents & ERTS_POLL_EV_OUT) {
-		    oready(state->driver.select->outport, state, current_cio_time);
+		    oready(state->driver.select->outport, state);
 		}
 		/* Someone might have deselected input since revents
 		   was read (true also on the non-smp emulator since
 		   oready() may have been called); therefore, update
 		   revents... */
-		revents &= state->events;
+                revents &= state->events;
 		if (revents & ERTS_POLL_EV_IN) {
-		    iready(state->driver.select->inport, state, current_cio_time);
+		    iready(state->driver.select->inport, state);
 		}
 	    }
 	    else if (revents & ERTS_POLL_EV_NVAL) {
 		bad_fd_in_pollset(state,
                                   state->driver.select->inport,
                                   state->driver.select->outport);
-		add_active_fd(state->fd);
+                check_fd_cleanup(state, &free_select, &free_nif);
 	    }
 	    break;
 	}
@@ -2307,112 +1656,116 @@ ERTS_CIO_EXPORT(erts_check_io)(int do_wait)
             struct erts_nif_select_event in = {NIL};
             struct erts_nif_select_event out = {NIL};
             ErtsResource* resource = NULL;
-            ErtsPollEvents revents = pollres[i].events;
-
-            if (revents & ERTS_POLL_EV_ERR) {
-                /*
-                 * Handle error events by triggering all in/out events
-                 * that the NIF has selected.
-                 * We *do not* want to send a message that corresponds
-		 * to an event not selected.
-                 */
-                revents = state->events;
-            }
-            else {
-                revents &= (state->events | ERTS_POLL_EV_NVAL);
-            }
 
             if (revents & (ERTS_POLL_EV_IN|ERTS_POLL_EV_OUT)) {
                 if (revents & ERTS_POLL_EV_OUT) {
                     if (is_not_nil(state->driver.nif->out.pid)) {
                         out = state->driver.nif->out;
                         resource = state->driver.stop.resource;
-                        state->driver.nif->out.ddeselect_cnt = ERTS_NIF_DELAYED_DESELECT;
                         state->driver.nif->out.pid = NIL;
-                        add_active_fd(state->fd);
-                    }
-                    else {
-                        ASSERT(state->driver.nif->out.ddeselect_cnt >= 2);
-                        state->driver.nif->out.ddeselect_cnt--;
                     }
                 }
                 if (revents & ERTS_POLL_EV_IN) {
                     if (is_not_nil(state->driver.nif->in.pid)) {
                         in = state->driver.nif->in;
                         resource = state->driver.stop.resource;
-                        state->driver.nif->in.ddeselect_cnt = ERTS_NIF_DELAYED_DESELECT;
                         state->driver.nif->in.pid = NIL;
-                        add_active_fd(state->fd);
-                    }
-                    else {
-                        ASSERT(state->driver.nif->in.ddeselect_cnt >= 2);
-                        state->driver.nif->in.ddeselect_cnt--;
                     }
                 }
+                state->events &= ~revents;
             }
             else if (revents & ERTS_POLL_EV_NVAL) {
                 bad_fd_in_pollset(state, NIL, NIL);
-                add_active_fd(state->fd);
+                check_fd_cleanup(state, &free_select, &free_nif);
             }
 
-#ifdef ERTS_SMP
-            erts_smp_mtx_unlock(fd_mtx(fd));
-#endif
+            erts_mtx_unlock(fd_mtx(fd));
+
             if (is_not_nil(in.pid)) {
                 send_event_tuple(&in, resource, am_ready_input);
             }
             if (is_not_nil(out.pid)) {
                 send_event_tuple(&out, resource, am_ready_output);
             }
-            goto next_pollres_unlocked;
+            continue;
         }
 
-#if ERTS_CIO_HAVE_DRV_EVENT
-	case ERTS_EV_TYPE_DRV_EV: { /* Requested via driver_event()... */
-	    ErlDrvEventData event_data;
-	    ErtsPollEvents revents;
-	    ASSERT(state->driver.event);
-	    ASSERT(state->driver.event->data);
-	    event_data = state->driver.event->data;
-	    revents = pollres[i].events;
-	    revents &= ~state->driver.event->removed_events;
-
-	    if (revents) {
-		event_data->events = state->events;
-		event_data->revents = revents;
-		eready(state->driver.event->port, state, event_data, current_cio_time);
-	    }
-	    break;
-	}
-#endif
+        case ERTS_EV_TYPE_STOP_NIF: {
+            resource = state->driver.stop.resource;
+            state->type = ERTS_EV_TYPE_NONE;
+            goto case_ERTS_EV_TYPE_NONE;
+        }
 
+        case ERTS_EV_TYPE_STOP_USE: {
+#if ERTS_POLL_USE_FALLBACK
+            ASSERT(psi->ps == get_fallback());
+#endif
+            drv_ptr = state->driver.stop.drv_ptr;
+            state->type = ERTS_EV_TYPE_NONE;
+            /* fallthrough */
 	case ERTS_EV_TYPE_NONE: /* Deselected ... */
+        case_ERTS_EV_TYPE_NONE:
+            ASSERT(!state->events && !state->active_events && !state->flags);
+            check_fd_cleanup(state, &free_select, &free_nif);
 	    break;
+        }
 
 	default: { /* Error */
 	    erts_dsprintf_buf_t *dsbufp;
 	    dsbufp = erts_create_logger_dsbuf();
 	    erts_dsprintf(dsbufp,
 			  "Invalid event request type for fd in erts_poll()! "
-			  "fd=%d, event request type=%sd\n", (int) state->fd,
+			  "fd=%d, event request type=%d\n", (int) state->fd,
 			  (int) state->type);
 	    ASSERT(0);
 	    deselect(state, 0);
-	    add_active_fd(state->fd);
 	    break;
 	}
 	}
 
-	next_pollres:;
-#ifdef ERTS_SMP
-	erts_smp_mtx_unlock(fd_mtx(fd));
-#endif
-        next_pollres_unlocked:;
-    }
+	erts_mtx_unlock(fd_mtx(fd));
 
-    erts_smp_atomic_set_nob(&pollset.in_poll_wait, 0);
-    erts_free(ERTS_ALC_T_TMP, pollres);
-    forget_removed(&pollset);
+        if (drv_ptr) {
+            int was_unmasked = erts_block_fpe();
+            DTRACE1(driver_stop_select, drv_ptr->name);
+            LTTNG1(driver_stop_select, drv_ptr->name);
+            (*drv_ptr->stop_select)((ErlDrvEvent) fd, NULL);
+            erts_unblock_fpe(was_unmasked);
+            if (drv_ptr->handle) {
+		erts_ddll_dereference_driver(drv_ptr->handle);
+	    }
+        }
+        if (resource) {
+            erts_resource_stop(resource, (ErlNifEvent)fd, 1);
+            enif_release_resource(resource->data);
+        }
+        if (free_select)
+            free_drv_select_data(free_select);
+        if (free_nif)
+            free_nif_select_data(free_nif);
+    }
+
+    /* The entire pollres array was filled with events,
+     * grow it for the next call. We do this for two reasons:
+     * 1. Pulling out more events in on go will increase throughput
+     * 2. If the polling implementation is not fair, this will make
+     *    sure that we get all fds that we can. i.e. if 12 fds are
+     *    constantly active, but we only have a pollres_len of 10,
+     *    two of the fds may never be triggered depending on what the
+     *    kernel decides to do.
+     **/
+    if (pollres_len == psi->pollres_len) {
+        int ev_state_len = drv_ev_state_len();
+        erts_free(ERTS_ALC_T_POLLSET, psi->pollres);
+        psi->pollres_len *= 2;
+        /* Never grow it larger than the current drv_ev_state.len size */
+        if (psi->pollres_len > ev_state_len)
+            psi->pollres_len = ev_state_len;
+        psi->pollres = erts_alloc(ERTS_ALC_T_POLLSET,
+                                  sizeof(ErtsPollResFd) * psi->pollres_len);
+    }
+
+    ERTS_MSACC_POP_STATE();
 }
 
 static void
@@ -2506,16 +1859,16 @@ static int drv_ev_state_cmp(void *des1, void *des2)
 static void *drv_ev_state_alloc(void *des_tmpl)
 {
     ErtsDrvEventState *evstate;
-    erts_smp_spin_lock(&state_prealloc_lock);
-    if (state_prealloc_first == NULL) {
-	erts_smp_spin_unlock(&state_prealloc_lock);
+    erts_spin_lock(&drv_ev_state.prealloc_lock);
+    if (drv_ev_state.prealloc_first == NULL) {
+	erts_spin_unlock(&drv_ev_state.prealloc_lock);
 	evstate = (ErtsDrvEventState *) 
 	    erts_alloc(ERTS_ALC_T_DRV_EV_STATE, sizeof(ErtsDrvEventState));
     } else {
-	evstate = state_prealloc_first;
-	state_prealloc_first = (ErtsDrvEventState *) evstate->hb.next;
-	--num_state_prealloc;
-	erts_smp_spin_unlock(&state_prealloc_lock);
+	evstate = drv_ev_state.prealloc_first;
+	drv_ev_state.prealloc_first = (ErtsDrvEventState *) evstate->hb.next;
+	--drv_ev_state.num_prealloc;
+	erts_spin_unlock(&drv_ev_state.prealloc_lock);
     }
     /* XXX: Already valid data if prealloced, could ignore template! */
     *evstate = *((ErtsDrvEventState *) des_tmpl);
@@ -2525,60 +1878,200 @@ static void *drv_ev_state_alloc(void *des_tmpl)
 
 static void drv_ev_state_free(void *des)
 {
-    erts_smp_spin_lock(&state_prealloc_lock);
-    ((ErtsDrvEventState *) des)->hb.next = &state_prealloc_first->hb;
-    state_prealloc_first = (ErtsDrvEventState *) des;
-    ++num_state_prealloc;
-    erts_smp_spin_unlock(&state_prealloc_lock);
+    erts_spin_lock(&drv_ev_state.prealloc_lock);
+    ((ErtsDrvEventState *) des)->hb.next = &drv_ev_state.prealloc_first->hb;
+    drv_ev_state.prealloc_first = (ErtsDrvEventState *) des;
+    ++drv_ev_state.num_prealloc;
+    erts_spin_unlock(&drv_ev_state.prealloc_lock);
 }
 #endif
 
+#define ERTS_MAX_NO_OF_POLL_THREADS ERTS_MAX_NO_OF_SCHEDULERS
+
+static char *
+get_arg(char* rest, char** argv, int* ip)
+{
+    int i = *ip;
+    if (*rest == '\0') {
+	if (argv[i+1] == NULL) {
+	    erts_fprintf(stderr, "too few arguments\n");
+	    erts_usage();
+	}
+        argv[i++] = NULL;
+        rest = argv[i];
+    }
+    argv[i] = NULL;
+    *ip = i;
+    return rest;
+}
+
+static void
+parse_args(int *argc, char **argv, int concurrent_waiters)
+{
+    int i = 0, j;
+    int no_pollsets = 0, no_poll_threads = 0,
+        no_pollsets_percentage = 0,
+        no_poll_threads_percentage = 0;
+    ASSERT(argc && argv);
+    while (i < *argc) {
+	if(argv[i][0] == '-') {
+	    switch (argv[i][1]) {
+            case 'I': {
+                if (strncmp(argv[i]+2, "Ot", 2) == 0) {
+                    char *arg = get_arg(argv[i]+4, argv, &i);
+                    if (sscanf(arg, "%d", &no_poll_threads) != 1 ||
+                        no_poll_threads < 1 ||
+                        ERTS_MAX_NO_OF_POLL_THREADS < no_poll_threads) {
+                        erts_fprintf(stderr,"bad I/O poll threads number: %s\n", arg);
+                        erts_usage();
+                    }
+                } else if (strncmp(argv[i]+2, "Op", 3) == 0) {
+                    char *arg = get_arg(argv[i]+4, argv, &i);
+                    if (sscanf(arg, "%d", &no_pollsets) != 1 ||
+                        no_pollsets < 1) {
+                        erts_fprintf(stderr,"bad I/O pollset number: %s\n", arg);
+                        erts_usage();
+                    }
+                } else if (strncmp(argv[i]+2, "OPt", 4) == 0) {
+                    char *arg = get_arg(argv[i]+5, argv, &i);
+                    if (sscanf(arg, "%d", &no_poll_threads_percentage) != 1 ||
+                        no_poll_threads_percentage < 0 ||
+                        no_poll_threads_percentage > 100) {
+                        erts_fprintf(stderr,"bad I/O poll thread percentage number: %s\n", arg);
+                        erts_usage();
+                    }
+                } else if (strncmp(argv[i]+2, "OPp", 4) == 0) {
+                    char *arg = get_arg(argv[i]+5, argv, &i);
+                    if (sscanf(arg, "%d", &no_pollsets_percentage) != 1 ||
+                        no_pollsets_percentage < 0 ||
+                        no_pollsets_percentage > 100) {
+                        erts_fprintf(stderr,"bad I/O pollset percentage number: %s\n", arg);
+                        erts_usage();
+                    }
+                } else {
+                    break;
+                }
+                break;
+            }
+            case 'K':
+                (void)get_arg(argv[i]+2, argv, &i);
+                break;
+            case '-':
+                goto args_parsed;
+            default:
+                break;
+            }
+        }
+        i++;
+    }
+
+args_parsed:
+
+    if (!concurrent_waiters) {
+        no_pollsets = no_poll_threads;
+        no_pollsets_percentage = 100;
+    }
+
+    if (no_poll_threads == 0) {
+        if (no_poll_threads_percentage == 0)
+            no_poll_threads = 1; /* This is the default */
+        else {
+            no_poll_threads = erts_no_schedulers * no_poll_threads_percentage / 100;
+            if (no_poll_threads < 1)
+                no_poll_threads = 1;
+        }
+    }
+
+    if (no_pollsets == 0) {
+        if (no_pollsets_percentage == 0)
+            no_pollsets = 1; /* This is the default */
+        else {
+            no_pollsets = no_poll_threads * no_pollsets_percentage / 100;
+            if (no_pollsets < 1)
+                no_pollsets = 1;
+        }
+    }
+
+    if (no_poll_threads < no_pollsets) {
+        erts_fprintf(stderr,
+                     "number of IO poll threads has to be greater or equal to "
+                     "the number of \nIO pollsets. Current values are set to: \n"
+                     "  -IOt %d -IOp %d\n",
+                     no_poll_threads, no_pollsets);
+        erts_usage();
+    }
+
+    /* Handled arguments have been marked with NULL. Slide arguments
+       not handled towards the beginning of argv. */
+    for (i = 0, j = 0; i < *argc; i++) {
+	if (argv[i])
+	    argv[j++] = argv[i];
+    }
+    *argc = j;
+
+    erts_no_pollsets = no_pollsets;
+    erts_no_poll_threads = no_poll_threads;
+}
+
 void
-ERTS_CIO_EXPORT(erts_init_check_io)(void)
+erts_init_check_io(int *argc, char **argv)
 {
+    int j, concurrent_waiters, no_poll_threads;
     ERTS_CT_ASSERT((INT_MIN & (ERL_NIF_SELECT_STOP_CALLED |
                                ERL_NIF_SELECT_STOP_SCHEDULED |
                                ERL_NIF_SELECT_INVALID_EVENT |
                                ERL_NIF_SELECT_FAILED)) == 0);
-    erts_smp_atomic_init_nob(&erts_check_io_time, 0);
-    erts_smp_atomic_init_nob(&pollset.in_poll_wait, 0);
-
-    ERTS_CIO_POLL_INIT();
-    pollset.ps = ERTS_CIO_NEW_POLLSET();
-
-    pollset.active_fd.six = 0;
-    pollset.active_fd.eix = 0;
-    erts_smp_atomic32_init_nob(&pollset.active_fd.no, 0);
-    pollset.active_fd.size = ERTS_ACTIVE_FD_INC;
-    pollset.active_fd.array = erts_alloc(ERTS_ALC_T_ACTIVE_FD_ARR,
-					 sizeof(ErtsSysFdType)*ERTS_ACTIVE_FD_INC);
-#ifdef DEBUG
-    {
-	int i;
-	for (i = 0; i < ERTS_ACTIVE_FD_INC; i++)
-	    pollset.active_fd.array[i] = ERTS_SYS_FD_INVALID;
-    }
+
+
+    erts_poll_init(&concurrent_waiters);
+#if ERTS_POLL_USE_FALLBACK
+    erts_poll_init_flbk(NULL);
 #endif
 
+    parse_args(argc, argv, concurrent_waiters);
 
-#ifdef ERTS_SMP
-    init_removed_fd_alloc();
-    pollset.removed_list = NULL;
-    erts_smp_spinlock_init(&pollset.removed_list_lock, "pollset_rm_list", NIL,
-        ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_IO);
-    {
-        int i;
-        for (i=0; i<DRV_EV_STATE_LOCK_CNT; i++) {
-            erts_smp_mtx_init(&drv_ev_state_locks[i].lck, "drv_ev_state", make_small(i),
-                ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_IO);
-        }
-    }
+    /* Create the actual pollsets */
+    pollsetv = erts_alloc(ERTS_ALC_T_POLLSET,sizeof(ErtsPollSet *) * erts_no_pollsets);
+
+    for (j=0; j < erts_no_pollsets; j++)
+        pollsetv[j] = erts_poll_create_pollset(j);
+
+#if ERTS_POLL_USE_FALLBACK
+    flbk_pollset = erts_poll_create_pollset_flbk(-1);
+#endif
+
+    no_poll_threads = erts_no_poll_threads;
+#if ERTS_POLL_USE_FALLBACK
+    no_poll_threads++;
+#endif
+
+    psiv = erts_alloc(ERTS_ALC_T_POLLSET, sizeof(ErtsPollThread) * no_poll_threads);
+
+#if ERTS_POLL_USE_FALLBACK
+    psiv[0].pollres_len = ERTS_CHECK_IO_POLL_RES_LEN;
+    psiv[0].pollres = erts_alloc(ERTS_ALC_T_POLLSET,
+        sizeof(ErtsPollResFd) * ERTS_CHECK_IO_POLL_RES_LEN);
+    psiv[0].ps = get_fallback();
+    psiv++;
 #endif
+
+    for (j = 0; j < erts_no_poll_threads; j++) {
+        psiv[j].pollres_len = ERTS_CHECK_IO_POLL_RES_LEN;
+        psiv[j].pollres = erts_alloc(ERTS_ALC_T_POLLSET,
+                                      sizeof(ErtsPollResFd) * ERTS_CHECK_IO_POLL_RES_LEN);
+        psiv[j].ps = pollsetv[j % erts_no_pollsets];
+    }
+
+    for (j=0; j < ERTS_CHECK_IO_DRV_EV_STATE_LOCK_CNT; j++) {
+        erts_mtx_init(&drv_ev_state.locks[j].lck, "drv_ev_state", make_small(j),
+                          ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_IO);
+    }
+
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    max_fds = ERTS_CIO_POLL_MAX_FDS();
-    erts_smp_atomic_init_nob(&drv_ev_state_len, 0);
-    drv_ev_state = NULL;
-    erts_smp_mtx_init(&drv_ev_state_grow_lock, "drv_ev_state_grow", NIL,
+    drv_ev_state.max_fds = erts_poll_max_fds();
+    erts_atomic_init_nob(&drv_ev_state.len, 0);
+    drv_ev_state.v = NULL;
+    erts_mtx_init(&drv_ev_state.grow_lock, "drv_ev_state_grow", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_IO);
 #else
     {
@@ -2587,153 +2080,182 @@ ERTS_CIO_EXPORT(erts_init_check_io)(void)
 	hf.cmp = &drv_ev_state_cmp;
 	hf.alloc = &drv_ev_state_alloc;
 	hf.free = &drv_ev_state_free;
-	num_state_prealloc = 0;
-	state_prealloc_first = NULL;
-	erts_smp_spinlock_init(&state_prealloc_lock,"state_prealloc", NIL,
-        ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_IO);
-
-	safe_hash_init(ERTS_ALC_T_DRV_EV_STATE, &drv_ev_state_tab, "drv_ev_state_tab",
+	drv_ev_state.num_prealloc = 0;
+	drv_ev_state.prealloc_first = NULL;
+	erts_spinlock_init(&drv_ev_state.prealloc_lock, "state_prealloc", NIL,
+                               ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_IO);
+	safe_hash_init(ERTS_ALC_T_DRV_EV_STATE, &drv_ev_state.tab, "drv_ev_state_tab",
             ERTS_LOCK_FLAGS_CATEGORY_IO, DRV_EV_STATE_HTAB_SIZE, hf);
     }
 #endif
 }
 
 int
-ERTS_CIO_EXPORT(erts_check_io_max_files)(void)
+erts_check_io_max_files(void)
 {
 #ifdef  ERTS_SYS_CONTINOUS_FD_NUMBERS
-    return max_fds;
+    return drv_ev_state.max_fds;
 #else
-    return ERTS_POLL_EXPORT(erts_poll_max_fds)();
+    return erts_poll_max_fds();
 #endif
 }
 
 Uint
-ERTS_CIO_EXPORT(erts_check_io_size)(void)
+erts_check_io_size(void)
 {
-    Uint res;
+    Uint res = 0;
     ErtsPollInfo pi;
-    ERTS_CIO_POLL_INFO(pollset.ps, &pi);
-    res = pi.memory_size;
+    int i;
+
+#if ERTS_POLL_USE_FALLBACK
+    erts_poll_info(get_fallback(), &pi);
+    res += pi.memory_size;
+#endif
+
+    for (i = 0; i < erts_no_pollsets; i++) {
+        erts_poll_info(pollsetv[i], &pi);
+        res += pi.memory_size;
+    }
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    res += sizeof(ErtsDrvEventState) * erts_smp_atomic_read_nob(&drv_ev_state_len);
+    res += sizeof(ErtsDrvEventState) * erts_atomic_read_nob(&drv_ev_state.len);
 #else
-    res += safe_hash_table_sz(&drv_ev_state_tab);
+    res += safe_hash_table_sz(&drv_ev_state.tab);
     {
 	SafeHashInfo hi;
-	safe_hash_get_info(&hi, &drv_ev_state_tab);
+	safe_hash_get_info(&hi, &drv_ev_state.tab);
 	res += hi.objs * sizeof(ErtsDrvEventState);
     }
-    erts_smp_spin_lock(&state_prealloc_lock);
-    res += num_state_prealloc * sizeof(ErtsDrvEventState);
-    erts_smp_spin_unlock(&state_prealloc_lock);
+    erts_spin_lock(&drv_ev_state.prealloc_lock);
+    res += drv_ev_state.num_prealloc * sizeof(ErtsDrvEventState);
+    erts_spin_unlock(&drv_ev_state.prealloc_lock);
 #endif
     return res;
 }
 
 Eterm
-ERTS_CIO_EXPORT(erts_check_io_info)(void *proc)
+erts_check_io_info(void *proc)
 {
     Process *p = (Process *) proc;
-    Eterm tags[16], values[16], res;
-    Uint sz, *szp, *hp, **hpp, memory_size;
-    Sint i;
-    ErtsPollInfo pi;
-    erts_aint_t cio_time = erts_smp_atomic_read_acqb(&erts_check_io_time);
-    int active_fds = (int) erts_smp_atomic32_read_acqb(&pollset.active_fd.no);
+    Eterm tags[16], values[16], res, list = NIL;
+    Uint sz, *szp, *hp, **hpp;
+    ErtsPollInfo *piv;
+    Sint i, j = 0, len;
+    int no_pollsets = erts_no_pollsets + ERTS_POLL_USE_FALLBACK;
+    ERTS_CT_ASSERT(ERTS_POLL_USE_FALLBACK == 0 || ERTS_POLL_USE_FALLBACK == 1);
 
-    while (1) {
-	erts_aint_t post_cio_time;
-	int post_active_fds;
+    piv = erts_alloc(ERTS_ALC_T_TMP, sizeof(ErtsPollInfo) * no_pollsets);
 
-	ERTS_CIO_POLL_INFO(pollset.ps, &pi);
+#if ERTS_POLL_USE_FALLBACK
+    erts_poll_info_flbk(get_fallback(), &piv[0]);
+    piv[0].poll_threads = 1;
+    piv[0].active_fds = 0;
+    piv++;
+#endif
 
-	post_cio_time = erts_smp_atomic_read_mb(&erts_check_io_time);
-	post_active_fds = (int) erts_smp_atomic32_read_acqb(&pollset.active_fd.no);
-	if (cio_time == post_cio_time && active_fds == post_active_fds)
-	    break;
-	cio_time = post_cio_time;
-	active_fds = post_active_fds;
+    for (j = 0; j < erts_no_pollsets; j++) {
+        erts_poll_info(pollsetv[j], &piv[j]);
+        piv[j].active_fds = 0;
+        piv[j].poll_threads = erts_no_poll_threads / erts_no_pollsets;
+        if (erts_no_poll_threads % erts_no_pollsets > j)
+            piv[j].poll_threads++;
     }
 
-    memory_size = pi.memory_size;
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    memory_size += sizeof(ErtsDrvEventState) * erts_smp_atomic_read_nob(&drv_ev_state_len);
+    i = 0;
+    erts_mtx_lock(&drv_ev_state.grow_lock);
+    len = erts_atomic_read_nob(&drv_ev_state.len);
+    for (i = 0; i < ERTS_CHECK_IO_DRV_EV_STATE_LOCK_CNT; i++) {
+        erts_mtx_lock(&drv_ev_state.locks[i].lck);
+        for (j = i; j < len; j+=ERTS_CHECK_IO_DRV_EV_STATE_LOCK_CNT) {
+            ErtsDrvEventState *state = get_drv_ev_state(j);
+            int pollsetid = get_pollset_id(j);
+            ASSERT(fd_mtx(j) == &drv_ev_state.locks[i].lck);
+            if (state->flags & ERTS_EV_FLAG_FALLBACK)
+                pollsetid = -1;
+            if (state->driver.select
+                && (state->type == ERTS_EV_TYPE_DRV_SEL)
+                && (is_iotask_active(&state->driver.select->iniotask)
+                    || is_iotask_active(&state->driver.select->outiotask)))
+                piv[pollsetid].active_fds++;
+        }
+        erts_mtx_unlock(&drv_ev_state.locks[i].lck);
+    }
+    erts_mtx_unlock(&drv_ev_state.grow_lock);
+
+    piv[0].memory_size += sizeof(ErtsDrvEventState) * erts_atomic_read_nob(&drv_ev_state.len);
 #else
-    memory_size += safe_hash_table_sz(&drv_ev_state_tab);
+    piv[0].memory_size += safe_hash_table_sz(&drv_ev_state.tab);
     {
-	SafeHashInfo hi;
-	safe_hash_get_info(&hi, &drv_ev_state_tab);
-	memory_size += hi.objs * sizeof(ErtsDrvEventState);
+        SafeHashInfo hi;
+        safe_hash_get_info(&hi, &drv_ev_state.tab);
+        piv[0].memory_size += hi.objs * sizeof(ErtsDrvEventState);
     }
-    erts_smp_spin_lock(&state_prealloc_lock);
-    memory_size += num_state_prealloc * sizeof(ErtsDrvEventState);
-    erts_smp_spin_unlock(&state_prealloc_lock);
+    erts_spin_lock(&drv_ev_state.prealloc_lock);
+    piv[0].memory_size += drv_ev_state.num_prealloc * sizeof(ErtsDrvEventState);
+    erts_spin_unlock(&drv_ev_state.prealloc_lock);
 #endif
 
     hpp = NULL;
     szp = &sz;
     sz = 0;
 
- bld_it:
-    i = 0;
+    piv -= ERTS_POLL_USE_FALLBACK;
 
-    tags[i] = erts_bld_atom(hpp, szp, "name");
-    values[i++] = erts_bld_atom(hpp, szp, "erts_poll");
+ bld_it:
 
-    tags[i] = erts_bld_atom(hpp, szp, "primary");
-    values[i++] = erts_bld_atom(hpp, szp, pi.primary);
+    for (j = no_pollsets-1; j >= 0; j--) {
+        i = 0;
 
-    tags[i] = erts_bld_atom(hpp, szp, "fallback");
-    values[i++] = erts_bld_atom(hpp, szp, pi.fallback ? pi.fallback : "false");
+        tags[i] = erts_bld_atom(hpp, szp, "name");
+        values[i++] = erts_bld_atom(hpp, szp, "erts_poll");
 
-    tags[i] = erts_bld_atom(hpp, szp, "kernel_poll");
-    values[i++] = erts_bld_atom(hpp, szp,
-				pi.kernel_poll ? pi.kernel_poll : "false");
+        tags[i] = erts_bld_atom(hpp, szp, "primary");
+        values[i++] = erts_bld_atom(hpp, szp, piv[j].primary);
 
-    tags[i] = erts_bld_atom(hpp, szp, "memory_size");
-    values[i++] = erts_bld_uint(hpp, szp, memory_size);
+        tags[i] = erts_bld_atom(hpp, szp, "kernel_poll");
+        values[i++] = erts_bld_atom(hpp, szp,
+                                    piv[j].kernel_poll ? piv[j].kernel_poll : "false");
 
-    tags[i] = erts_bld_atom(hpp, szp, "total_poll_set_size");
-    values[i++] = erts_bld_uint(hpp, szp, (Uint) pi.poll_set_size);
+        tags[i] = erts_bld_atom(hpp, szp, "memory_size");
+        values[i++] = erts_bld_uint(hpp, szp, piv[j].memory_size);
 
-    if (pi.fallback) {
-	tags[i] = erts_bld_atom(hpp, szp, "fallback_poll_set_size");
-	values[i++] = erts_bld_uint(hpp, szp, (Uint) pi.fallback_poll_set_size);
-    }
+        tags[i] = erts_bld_atom(hpp, szp, "total_poll_set_size");
+        values[i++] = erts_bld_uint(hpp, szp, piv[j].poll_set_size);
 
-    tags[i] = erts_bld_atom(hpp, szp, "lazy_updates");
-    values[i++] = pi.lazy_updates ? am_true : am_false;
+        tags[i] = erts_bld_atom(hpp, szp, "lazy_updates");
+        values[i++] = piv[j].lazy_updates ? am_true : am_false;
 
-    if (pi.lazy_updates) {
-	tags[i] = erts_bld_atom(hpp, szp, "pending_updates");
-	values[i++] = erts_bld_uint(hpp, szp, (Uint) pi.pending_updates);
-    }
+        tags[i] = erts_bld_atom(hpp, szp, "pending_updates");
+        values[i++] = erts_bld_uint(hpp, szp, piv[j].pending_updates);
 
-    tags[i] = erts_bld_atom(hpp, szp, "batch_updates");
-    values[i++] = pi.batch_updates ? am_true : am_false;
+        tags[i] = erts_bld_atom(hpp, szp, "batch_updates");
+        values[i++] = piv[j].batch_updates ? am_true : am_false;
 
-    tags[i] = erts_bld_atom(hpp, szp, "concurrent_updates");
-    values[i++] = pi.concurrent_updates ? am_true : am_false;
+        tags[i] = erts_bld_atom(hpp, szp, "concurrent_updates");
+        values[i++] = piv[j].concurrent_updates ? am_true : am_false;
 
-    tags[i] = erts_bld_atom(hpp, szp, "max_fds");
-    values[i++] = erts_bld_uint(hpp, szp, (Uint) pi.max_fds);
+        tags[i] = erts_bld_atom(hpp, szp, "fallback");
+        values[i++] = piv[j].is_fallback ? am_true : am_false;
 
-    tags[i] = erts_bld_atom(hpp, szp, "active_fds");
-    values[i++] = erts_bld_uint(hpp, szp, (Uint) active_fds);
+        tags[i] = erts_bld_atom(hpp, szp, "max_fds");
+        values[i++] = erts_bld_uint(hpp, szp, piv[j].max_fds);
 
-#ifdef ERTS_POLL_COUNT_AVOIDED_WAKEUPS
-    tags[i] = erts_bld_atom(hpp, szp, "no_avoided_wakeups");
-    values[i++] = erts_bld_uint(hpp, szp, (Uint) pi.no_avoided_wakeups);
+        tags[i] = erts_bld_atom(hpp, szp, "active_fds");
+        values[i++] = erts_bld_uint(hpp, szp, piv[j].active_fds);
 
-    tags[i] = erts_bld_atom(hpp, szp, "no_avoided_interrupts");
-    values[i++] = erts_bld_uint(hpp, szp, (Uint) pi.no_avoided_interrupts);
+        tags[i] = erts_bld_atom(hpp, szp, "poll_threads");
+        values[i++] = erts_bld_uint(hpp, szp, piv[j].poll_threads);
 
-    tags[i] = erts_bld_atom(hpp, szp, "no_interrupt_timed");
-    values[i++] = erts_bld_uint(hpp, szp, (Uint) pi.no_interrupt_timed);
-#endif
+        res = erts_bld_2tup_list(hpp, szp, i, tags, values);
 
-    res = erts_bld_2tup_list(hpp, szp, i, tags, values);
+        if (!hpp) {
+            *szp += 2;
+        }
+        else {
+            list = CONS(*hpp, res, list);
+            *hpp += 2;
+        }
+    }
 
     if (!hpp) {
 	hp = HAlloc(p, sz);
@@ -2742,386 +2264,442 @@ ERTS_CIO_EXPORT(erts_check_io_info)(void *proc)
 	goto bld_it;
     }
 
-    return res;
+    erts_free(ERTS_ALC_T_TMP, piv);
+
+    return list;
 }
 
 static ERTS_INLINE ErtsPollEvents
-print_events(ErtsPollEvents ev)
+print_events(erts_dsprintf_buf_t *dsbufp, ErtsPollEvents ev)
 {
     int first = 1;
+    if(ev == ERTS_POLL_EV_NONE) {
+        erts_dsprintf(dsbufp, "N/A");
+        return 0;
+    }
     if(ev & ERTS_POLL_EV_IN) {
 	ev &= ~ERTS_POLL_EV_IN;
-	erts_printf("%s%s", first ? "" : "|", "IN");
+	erts_dsprintf(dsbufp, "%s%s", first ? "" : "|", "IN");
 	first = 0;
     }
     if(ev & ERTS_POLL_EV_OUT) {
 	ev &= ~ERTS_POLL_EV_OUT;
-	erts_printf("%s%s", first ? "" : "|", "OUT");
+	erts_dsprintf(dsbufp, "%s%s", first ? "" : "|", "OUT");
 	first = 0;
     }
     /* The following should not appear... */
     if(ev & ERTS_POLL_EV_NVAL) {
-	erts_printf("%s%s", first ? "" : "|", "NVAL");
+	erts_dsprintf(dsbufp, "%s%s", first ? "" : "|", "NVAL");
 	first = 0;
     }
     if(ev & ERTS_POLL_EV_ERR) {
-	erts_printf("%s%s", first ? "" : "|", "ERR");
+	erts_dsprintf(dsbufp, "%s%s", first ? "" : "|", "ERR");
 	first = 0;
     }
     if (ev)
-	erts_printf("%s0x%b32x", first ? "" : "|", (Uint32) ev);
+	erts_dsprintf(dsbufp, "%s0x%b32x", first ? "" : "|", (Uint32) ev);
     return ev;
 }
 
+static ERTS_INLINE void
+print_flags(erts_dsprintf_buf_t *dsbufp, EventStateFlags f)
+{
+    const char* delim = "";
+    if(f & ERTS_EV_FLAG_USED) {
+	erts_dsprintf(dsbufp, "%s","USED");
+	delim = "|";
+    }
+    if(f & ERTS_EV_FLAG_FALLBACK) {
+	erts_dsprintf(dsbufp, "%s%s", delim, "FLBK");
+        delim = "|";
+    }
+}
+
+#ifdef DEBUG_PRINT_MODE
+
+static ERTS_INLINE char *
+drvmode2str(int mode) {
+    switch (mode) {
+    case ERL_DRV_READ|ERL_DRV_USE: return "READ|USE";
+    case ERL_DRV_WRITE|ERL_DRV_USE: return "WRITE|USE";
+    case ERL_DRV_READ|ERL_DRV_WRITE|ERL_DRV_USE: return "READ|WRITE|USE";
+    case ERL_DRV_USE: return "USE";
+    case ERL_DRV_READ: return "READ";
+    case ERL_DRV_WRITE: return "WRITE";
+    case ERL_DRV_READ|ERL_DRV_WRITE: return "READ|WRITE";
+    default: return "UNKNOWN";
+    }
+}
+
+static ERTS_INLINE char *
+nifmode2str(enum ErlNifSelectFlags mode) {
+    switch (mode) {
+    case ERL_NIF_SELECT_READ: return "READ";
+    case ERL_NIF_SELECT_WRITE: return "WRITE";
+    case ERL_NIF_SELECT_STOP: return "STOP";
+    default: return "UNKNOWN";
+    }
+}
+
+#endif
+
 typedef struct {
     int used_fds;
     int num_errors;
     int no_driver_select_structs;
-    int no_driver_event_structs;
+    int no_enif_select_structs;
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
     int internal_fds;
     ErtsPollEvents *epep;
 #endif
 } IterDebugCounters;
 
-static void doit_erts_check_io_debug(void *vstate, void *vcounters)
+static int erts_debug_print_checkio_state(erts_dsprintf_buf_t *dsbufp,
+                                          ErtsDrvEventState *state,
+                                          ErtsPollEvents ep_events,
+                                          int internal)
 {
-    ErtsDrvEventState *state = (ErtsDrvEventState *) vstate;
-    IterDebugCounters *counters = (IterDebugCounters *) vcounters;
-    ErtsPollEvents cio_events = state->events;
-    ErtsSysFdType fd = state->fd;
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    int internal = 0;
-    ErtsPollEvents ep_events = counters->epep[(int) fd];
-#endif
-    int err = 0;
-
 #if defined(HAVE_FSTAT) && !defined(NO_FSTAT_ON_SYS_FD_TYPE)
     struct stat stat_buf;
 #endif
-
-    if (state->driver.select)
-	counters->no_driver_select_structs++;
-#if ERTS_CIO_HAVE_DRV_EVENT
-    if (state->driver.event)
-	counters->no_driver_event_structs++;
-#endif
-
+    ErtsSysFdType fd = state->fd;
+    ErtsPollEvents cio_events = state->events;
+    int err = 0;
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    if (state->events || ep_events) {
-	if (ep_events & ERTS_POLL_EV_NVAL) {
-	    ep_events &= ~ERTS_POLL_EV_NVAL;
-	    internal = 1;
-	    counters->internal_fds++;
-	}
-	else
-	    counters->used_fds++;
-#else
-    if (state->events) {
-	counters->used_fds++;
+    ErtsPollEvents aio_events = state->active_events;
 #endif
-	
-	erts_printf("fd=%d ", (int) fd);
-	
+    erts_dsprintf(dsbufp, "pollset=%d fd=%d ",
+                state->flags & ERTS_EV_FLAG_FALLBACK ? -1 : get_pollset_id(fd), (int) fd);
+
 #if defined(HAVE_FSTAT) && !defined(NO_FSTAT_ON_SYS_FD_TYPE)
-	if (fstat((int) fd, &stat_buf) < 0)
-	    erts_printf("type=unknown ");
-	else {
-	    erts_printf("type=");
+    if (fstat((int) fd, &stat_buf) < 0)
+        erts_dsprintf(dsbufp, "type=unknown ");
+    else {
+        erts_dsprintf(dsbufp, "type=");
 #ifdef S_ISSOCK
-	    if (S_ISSOCK(stat_buf.st_mode))
-		erts_printf("sock ");
-	    else
+        if (S_ISSOCK(stat_buf.st_mode))
+            erts_dsprintf(dsbufp, "sock ");
+        else
 #endif
 #ifdef S_ISFIFO
 	    if (S_ISFIFO(stat_buf.st_mode))
-		erts_printf("fifo ");
+		erts_dsprintf(dsbufp, "fifo ");
 	    else
 #endif
 #ifdef S_ISCHR
-	    if (S_ISCHR(stat_buf.st_mode))
-		erts_printf("chr ");
-	    else
+                if (S_ISCHR(stat_buf.st_mode))
+                    erts_dsprintf(dsbufp, "chr ");
+                else
 #endif
 #ifdef S_ISDIR
-	    if (S_ISDIR(stat_buf.st_mode))
-		erts_printf("dir ");
-	    else
+                    if (S_ISDIR(stat_buf.st_mode))
+                        erts_dsprintf(dsbufp, "dir ");
+                    else
 #endif
 #ifdef S_ISBLK
-	    if (S_ISBLK(stat_buf.st_mode))
-		erts_printf("blk ");
-	    else
+                        if (S_ISBLK(stat_buf.st_mode))
+                            erts_dsprintf(dsbufp, "blk ");
+                        else
 #endif
 #ifdef S_ISREG
-	    if (S_ISREG(stat_buf.st_mode))
-		erts_printf("reg ");
-	    else
+                            if (S_ISREG(stat_buf.st_mode))
+                                erts_dsprintf(dsbufp, "reg ");
+                            else
 #endif
 #ifdef S_ISLNK
-	    if (S_ISLNK(stat_buf.st_mode))
-		erts_printf("lnk ");
-	    else
+                                if (S_ISLNK(stat_buf.st_mode))
+                                    erts_dsprintf(dsbufp, "lnk ");
+                                else
 #endif
 #ifdef S_ISDOOR
-	    if (S_ISDOOR(stat_buf.st_mode))
-		erts_printf("door ");
-	    else
+                                    if (S_ISDOOR(stat_buf.st_mode))
+                                        erts_dsprintf(dsbufp, "door ");
+                                    else
 #endif
 #ifdef S_ISWHT
-	    if (S_ISWHT(stat_buf.st_mode))
-		erts_printf("wht ");
-	    else
+                                        if (S_ISWHT(stat_buf.st_mode))
+                                            erts_dsprintf(dsbufp, "wht ");
+                                        else
 #endif
 #ifdef S_ISXATTR
-	    if (S_ISXATTR(stat_buf.st_mode))
-		erts_printf("xattr ");
-	    else
+                                            if (S_ISXATTR(stat_buf.st_mode))
+                                                erts_dsprintf(dsbufp, "xattr ");
+                                            else
 #endif
-		erts_printf("unknown ");
-	}
+                                                erts_dsprintf(dsbufp, "unknown ");
+    }
 #else
-	erts_printf("type=unknown ");
+    erts_dsprintf(dsbufp, "type=unknown ");
 #endif
 
-	if (state->type == ERTS_EV_TYPE_DRV_SEL) {
-	    erts_printf("driver_select ");
-	    
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-	    if (internal) {
-		erts_printf("internal ");
-		err = 1;		    
-	    }
-	    
-	    if (cio_events == ep_events) {
-		erts_printf("ev=");
-		if (print_events(cio_events) != 0)
-		    err = 1;
-	    }
-	    else {
-		err = 1;
-		erts_printf("cio_ev=");
-		print_events(cio_events);
-		erts_printf(" ep_ev=");
-		print_events(ep_events);
-	    }
-#else
-	    if (print_events(cio_events) != 0)
-		err = 1;
-#endif
-	    erts_printf(" ");
-	    if (cio_events & ERTS_POLL_EV_IN) {
-		Eterm id = state->driver.select->inport;
-		if (is_nil(id)) {
-		    erts_printf("inport=none inname=none indrv=none ");
-		    err = 1;
-		}
-		else {
-		    ErtsPortNames *pnp = erts_get_port_names(id, ERTS_INVALID_ERL_DRV_PORT);
-		    erts_printf(" inport=%T inname=%s indrv=%s ",
-				id,
-				pnp->name ? pnp->name : "unknown",
-				(pnp->driver_name
-				 ? pnp->driver_name
-				 : "unknown"));
-		    erts_free_port_names(pnp);
-		}
-	    }
-	    if (cio_events & ERTS_POLL_EV_OUT) {
-		Eterm id = state->driver.select->outport;
-		if (is_nil(id)) {
-		    erts_printf("outport=none outname=none outdrv=none ");
-		    err = 1;
-		}
-		else {
-		    ErtsPortNames *pnp = erts_get_port_names(id, ERTS_INVALID_ERL_DRV_PORT);
-		    erts_printf(" outport=%T outname=%s outdrv=%s ",
-				id,
-				pnp->name ? pnp->name : "unknown",
-				(pnp->driver_name
-				 ? pnp->driver_name
-				 : "unknown"));
-		    erts_free_port_names(pnp);
-		}
-	    }
-	}
-        else if (state->type == ERTS_EV_TYPE_NIF) {
-            ErtsResource* r;
-            erts_printf("enif_select ");
+    if (state->type == ERTS_EV_TYPE_DRV_SEL) {
+        erts_dsprintf(dsbufp, "driver_select ");
 
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-            if (internal) {
-                erts_printf("internal ");
-                err = 1;
-            }
-
+        if (internal) {
+            erts_dsprintf(dsbufp, "internal ");
+            err = 1;
+        }
+        if (aio_events == cio_events) {
             if (cio_events == ep_events) {
-                erts_printf("ev=");
-                if (print_events(cio_events) != 0)
+                erts_dsprintf(dsbufp, "ev=");
+                if (print_events(dsbufp, cio_events) != 0)
                     err = 1;
             }
             else {
+                ErtsPollEvents ev = cio_events;
+                if (ev != ep_events && ep_events != ERTS_POLL_EV_NONE)
+                    err = 1;
+                erts_dsprintf(dsbufp, "cio_ev=");
+                print_events(dsbufp, cio_events);
+                erts_dsprintf(dsbufp, " ep_ev=");
+                print_events(dsbufp, ep_events);
+            }
+        } else {
+            erts_dsprintf(dsbufp, "cio_ev=");
+            print_events(dsbufp, cio_events);
+            erts_dsprintf(dsbufp, " aio_ev=");
+            print_events(dsbufp, aio_events);
+            if ((aio_events != ep_events && ep_events != ERTS_POLL_EV_NONE) ||
+                (aio_events != 0 && ep_events == ERTS_POLL_EV_NONE)) {
+                erts_dsprintf(dsbufp, " ep_ev=");
+                print_events(dsbufp, ep_events);
                 err = 1;
-                erts_printf("cio_ev=");
-                print_events(cio_events);
-                erts_printf(" ep_ev=");
-                print_events(ep_events);
             }
+        }
 #else
-            if (print_events(cio_events) != 0)
+        if (print_events(dsbufp, cio_events) != 0)
+            err = 1;
+#endif
+        erts_dsprintf(dsbufp, " ");
+        if (cio_events & ERTS_POLL_EV_IN) {
+            Eterm id = state->driver.select->inport;
+            if (is_nil(id)) {
+                erts_dsprintf(dsbufp, "inport=none inname=none indrv=none ");
                 err = 1;
-#endif
-            erts_printf(" inpid=%T dd_cnt=%b32d", state->driver.nif->in.pid,
-                        state->driver.nif->in.ddeselect_cnt);
-            erts_printf(" outpid=%T dd_cnt=%b32d", state->driver.nif->out.pid,
-                        state->driver.nif->out.ddeselect_cnt);
-            r = state->driver.stop.resource;
-            erts_printf(" resource=%p(%T:%T)", r, r->type->module, r->type->name);
+            }
+            else {
+                ErtsPortNames *pnp = erts_get_port_names(id, ERTS_INVALID_ERL_DRV_PORT);
+                erts_dsprintf(dsbufp, " inport=%T inname=%s indrv=%s ",
+                            id,
+                            pnp->name ? pnp->name : "unknown",
+                            (pnp->driver_name
+                             ? pnp->driver_name
+                             : "unknown"));
+                erts_free_port_names(pnp);
+            }
         }
-#if ERTS_CIO_HAVE_DRV_EVENT
-	else if (state->type == ERTS_EV_TYPE_DRV_EV) {
-	    Eterm id;
-	    erts_printf("driver_event ");
+        if (cio_events & ERTS_POLL_EV_OUT) {
+            Eterm id = state->driver.select->outport;
+            if (is_nil(id)) {
+                erts_dsprintf(dsbufp, "outport=none outname=none outdrv=none ");
+                err = 1;
+            }
+            else {
+                ErtsPortNames *pnp = erts_get_port_names(id, ERTS_INVALID_ERL_DRV_PORT);
+                erts_dsprintf(dsbufp, " outport=%T outname=%s outdrv=%s ",
+                            id,
+                            pnp->name ? pnp->name : "unknown",
+                            (pnp->driver_name
+                             ? pnp->driver_name
+                             : "unknown"));
+                erts_free_port_names(pnp);
+            }
+        }
+    }
+    else if (state->type == ERTS_EV_TYPE_NIF) {
+        ErtsResource* r;
+        erts_dsprintf(dsbufp, "enif_select ");
+
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-	    if (internal) {
-		erts_printf("internal ");
-		err = 1;		    
-	    }
-	    if (cio_events == ep_events) {
-		erts_printf("ev=0x%b32x", (Uint32) cio_events);
-	    }
-	    else {
-		err = 1;
-		erts_printf("cio_ev=0x%b32x", (Uint32) cio_events);
-		erts_printf(" ep_ev=0x%b32x", (Uint32) ep_events);
-	    }
+        if (internal) {
+            erts_dsprintf(dsbufp, "internal ");
+            err = 1;
+        }
+
+        if (cio_events == ep_events) {
+            erts_dsprintf(dsbufp, "ev=");
+            if (print_events(dsbufp, cio_events) != 0)
+                err = 1;
+        }
+        else {
+            err = 1;
+            erts_dsprintf(dsbufp, "cio_ev=");
+            print_events(dsbufp, cio_events);
+            erts_dsprintf(dsbufp, " ep_ev=");
+            print_events(dsbufp, ep_events);
+        }
 #else
-	    erts_printf("ev=0x%b32x", (Uint32) cio_events);
+        if (print_events(dsbufp, cio_events) != 0)
+            err = 1;
 #endif
-	    id = state->driver.event->port;
-	    if (is_nil(id)) {
-		erts_printf(" port=none name=none drv=none ");
-		err = 1;
-	    }
-	    else {
-		ErtsPortNames *pnp = erts_get_port_names(id, ERTS_INVALID_ERL_DRV_PORT);
-		erts_printf(" port=%T name=%s drv=%s ",
-			    id,
-			    pnp->name ? pnp->name : "unknown",
-			    (pnp->driver_name
-			     ? pnp->driver_name
-			     : "unknown"));
-		erts_free_port_names(pnp);
-	    }
-	}
+        erts_dsprintf(dsbufp, " inpid=%T", state->driver.nif->in.pid);
+        erts_dsprintf(dsbufp, " outpid=%T", state->driver.nif->out.pid);
+        r = state->driver.stop.resource;
+        erts_dsprintf(dsbufp, " resource=%p(%T:%T)", r, r->type->module, r->type->name);
+    }
+#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
+    else if (internal) {
+        erts_dsprintf(dsbufp, "internal ");
+        if (cio_events) {
+            err = 1;
+            erts_dsprintf(dsbufp, "cio_ev=");
+            print_events(dsbufp, cio_events);
+        }
+        if (ep_events) {
+            erts_dsprintf(dsbufp, "ep_ev=");
+            print_events(dsbufp, ep_events);
+        }
+    }
 #endif
+    else {
+        err = 1;
+        erts_dsprintf(dsbufp, "control_type=%d ", (int)state->type);
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-	else if (internal) {
-	    erts_printf("internal ");
-	    if (cio_events) {
-		err = 1;
-		erts_printf("cio_ev=");
-		print_events(cio_events);
-	    }
-	    if (ep_events) {
-		erts_printf("ep_ev=");
-		print_events(ep_events);
-	    }
-	}
+        if (cio_events == ep_events) {
+            erts_dsprintf(dsbufp, "ev=");
+            print_events(dsbufp, cio_events);
+        }
+        else {
+            erts_dsprintf(dsbufp, "cio_ev="); print_events(dsbufp, cio_events);
+            erts_dsprintf(dsbufp, " ep_ev="); print_events(dsbufp, ep_events);
+        }
+#else
+        erts_dsprintf(dsbufp, "ev=0x%b32x", (Uint32) cio_events);
 #endif
-	else {
-	    err = 1;
-	    erts_printf("control_type=%d ", (int)state->type);
+    }
+
+    erts_dsprintf(dsbufp, " flags="); print_flags(dsbufp, state->flags);
+    if (err) {
+        erts_dsprintf(dsbufp, " ERROR");
+    }
+    erts_dsprintf(dsbufp, "\r\n");
+    return err;
+}
+
+static void doit_erts_check_io_debug(void *vstate, void *vcounters,
+                                     erts_dsprintf_buf_t *dsbufp)
+{
+    ErtsDrvEventState *state = (ErtsDrvEventState *) vstate;
+    IterDebugCounters *counters = (IterDebugCounters *) vcounters;
+    int internal = 0;
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-	    if (cio_events == ep_events) {
-                erts_printf("ev=");
-                print_events(cio_events);
-	    }
-	    else {
-		erts_printf("cio_ev="); print_events(cio_events);
-		erts_printf(" ep_ev="); print_events(ep_events);
-	    }
+    ErtsSysFdType fd = state->fd;
+    ErtsPollEvents ep_events = counters->epep[(int) fd];
 #else
-	    erts_printf("ev=0x%b32x", (Uint32) cio_events);
+    ErtsPollEvents ep_events = ERTS_POLL_EV_NONE;
 #endif
+
+    if (state->driver.select) {
+	counters->no_driver_select_structs++;
+        ASSERT(state->events || (ep_events != 0 && ep_events != ERTS_POLL_EV_NONE));
+    }
+    if (state->driver.nif) {
+        counters->no_enif_select_structs++;
+        ASSERT(state->events || (ep_events != 0 && ep_events != ERTS_POLL_EV_NONE));
+    }
+
+#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
+    if (state->events || (ep_events != 0 && ep_events != ERTS_POLL_EV_NONE)) {
+	if (ep_events & ERTS_POLL_EV_NVAL) {
+	    ep_events &= ~ERTS_POLL_EV_NVAL;
+	    internal = 1;
+	    counters->internal_fds++;
 	}
-	
-	if (err) {
+	else
+	    counters->used_fds++;
+#else
+    if (state->events) {
+	counters->used_fds++;
+#endif
+	if (erts_debug_print_checkio_state(dsbufp, state, ep_events, internal)) {
 	    counters->num_errors++;
-	    erts_printf(" ERROR");
 	}
-	erts_printf("\n");
     }
 }
-    
+
+/* ciodpi can be NULL when called from etp-commands */
 int
-ERTS_CIO_EXPORT(erts_check_io_debug)(ErtsCheckIoDebugInfo *ciodip)
+erts_check_io_debug(ErtsCheckIoDebugInfo *ciodip)
 {
+    erts_dsprintf_buf_t *dsbufp = erts_create_logger_dsbuf();
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    int fd, len;
+    int fd, len, i;
 #endif
-    IterDebugCounters counters;
+    IterDebugCounters counters = {0};
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
     ErtsDrvEventState null_des;
 
     null_des.driver.select = NULL;
-#if ERTS_CIO_HAVE_DRV_EVENT
-    null_des.driver.event = NULL;
-#endif
+    null_des.driver.nif = NULL;
     null_des.driver.stop.drv_ptr = NULL;
     null_des.events = 0;
-    null_des.remove_cnt = 0;
     null_des.type = ERTS_EV_TYPE_NONE;
+    null_des.flags = 0;
+
+    counters.epep = erts_alloc(ERTS_ALC_T_TMP,
+                               sizeof(ErtsPollEvents)*drv_ev_state.max_fds);
 #endif
 
-    erts_printf("--- fds in pollset --------------------------------------\n");
 
-#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
+#if defined(ERTS_ENABLE_LOCK_CHECK)
     erts_lc_check_exact(NULL, 0); /* No locks should be locked */
 #endif
 
-    erts_smp_thr_progress_block(); /* stop the world to avoid messy locking */
+    if (ciodip)
+        erts_thr_progress_block(); /* stop the world to avoid messy locking */
 
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    counters.epep = erts_alloc(ERTS_ALC_T_TMP, sizeof(ErtsPollEvents)*max_fds);
-    ERTS_POLL_EXPORT(erts_poll_get_selected_events)(pollset.ps, counters.epep, max_fds);
-    counters.internal_fds = 0;
-#endif
-    counters.used_fds = 0;
-    counters.num_errors = 0;
-    counters.no_driver_select_structs = 0;
-    counters.no_driver_event_structs = 0;
+    len = erts_atomic_read_nob(&drv_ev_state.len);
 
-#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    len = erts_smp_atomic_read_nob(&drv_ev_state_len);
+#if ERTS_POLL_USE_FALLBACK
+    erts_dsprintf(dsbufp, "--- fds in flbk pollset ---------------------------------\n");
+    erts_poll_get_selected_events_flbk(get_fallback(), counters.epep,
+                                       drv_ev_state.max_fds);
     for (fd = 0; fd < len; fd++) {
-	doit_erts_check_io_debug((void *) &drv_ev_state[fd], (void *) &counters);
+        if (drv_ev_state.v[fd].flags & ERTS_EV_FLAG_FALLBACK)
+            doit_erts_check_io_debug(&drv_ev_state.v[fd], &counters, dsbufp);
+    }
+#endif
+    erts_dsprintf(dsbufp, "--- fds in pollset --------------------------------------\n");
+
+    for (i = 0; i < erts_no_pollsets; i++) {
+        erts_poll_get_selected_events(pollsetv[i],
+                                      counters.epep,
+                                      drv_ev_state.max_fds);
+        for (fd = 0; fd < len; fd++) {
+            if (!(drv_ev_state.v[fd].flags & ERTS_EV_FLAG_FALLBACK)
+                && get_pollset_id(fd) == i)
+                doit_erts_check_io_debug(&drv_ev_state.v[fd], &counters, dsbufp);
+        }
     }
-    for ( ; fd < max_fds; fd++) {
-	null_des.fd = fd;
-	doit_erts_check_io_debug((void *) &null_des, (void *) &counters);
+    for (fd = len ; fd < drv_ev_state.max_fds; fd++) {
+        null_des.fd = fd;
+        doit_erts_check_io_debug(&null_des, &counters, dsbufp);
     }
 #else
-    safe_hash_for_each(&drv_ev_state_tab, &doit_erts_check_io_debug, (void *) &counters);
+    safe_hash_for_each(&drv_ev_state.tab, &doit_erts_check_io_debug,
+                       &counters, dsbufp);
 #endif
 
-    erts_smp_thr_progress_unblock();
+    if (ciodip)
+        erts_thr_progress_unblock();
 
-    ciodip->no_used_fds = counters.used_fds;
-    ciodip->no_driver_select_structs = counters.no_driver_select_structs;
-    ciodip->no_driver_event_structs = counters.no_driver_event_structs;
+    if (ciodip) {
+        ciodip->no_used_fds = counters.used_fds;
+        ciodip->no_driver_select_structs = counters.no_driver_select_structs;
+        ciodip->no_enif_select_structs = counters.no_enif_select_structs;
+    }
 
-    erts_printf("\n");
-    erts_printf("used fds=%d\n", counters.used_fds);
-    erts_printf("Number of driver_select() structures=%d\n", counters.no_driver_select_structs);
-#if ERTS_CIO_HAVE_DRV_EVENT
-    erts_printf("Number of driver_event() structures=%d\n", counters.no_driver_event_structs);
-#endif
+    erts_dsprintf(dsbufp, "\n");
+    erts_dsprintf(dsbufp, "used fds=%d\n", counters.used_fds);
+    erts_dsprintf(dsbufp, "Number of driver_select() structures=%d\n", counters.no_driver_select_structs);
+    erts_dsprintf(dsbufp, "Number of enif_select() structures=%d\n", counters.no_enif_select_structs);
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    erts_printf("internal fds=%d\n", counters.internal_fds);
+    erts_dsprintf(dsbufp, "internal fds=%d\n", counters.internal_fds);
 #endif
-    erts_printf("---------------------------------------------------------\n");
-    fflush(stdout);
+    erts_dsprintf(dsbufp, "---------------------------------------------------------\n");
+    erts_send_error_to_logger_nogl(dsbufp);
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
     erts_free(ERTS_ALC_T_TMP, (void *) counters.epep);
 #endif
@@ -3130,11 +2708,19 @@ ERTS_CIO_EXPORT(erts_check_io_debug)(ErtsCheckIoDebugInfo *ciodip)
 }
 
 #ifdef ERTS_ENABLE_LOCK_COUNT
-void ERTS_CIO_EXPORT(erts_lcnt_update_cio_locks)(int enable) {
+void erts_lcnt_update_cio_locks(int enable) {
+    int i;
 #ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
-    erts_lcnt_enable_hash_lock_count(&drv_ev_state_tab, ERTS_LOCK_FLAGS_CATEGORY_IO, enable);
+    erts_lcnt_enable_hash_lock_count(&drv_ev_state.tab, ERTS_LOCK_FLAGS_CATEGORY_IO, enable);
 #else
     (void)enable;
 #endif
+
+#if ERTS_POLL_USE_FALLBACK
+    erts_lcnt_enable_pollset_lock_count_flbk(get_fallback(), enable);
+#endif
+
+    for (i = 0; i < erts_no_pollsets; i++)
+        erts_lcnt_enable_pollset_lock_count(pollsetv[i], enable);
 }
 #endif /* ERTS_ENABLE_LOCK_COUNT */
diff --git a/erts/emulator/sys/common/erl_check_io.h b/erts/emulator/sys/common/erl_check_io.h
index 2d3bb98afa..443ef1264c 100644
--- a/erts/emulator/sys/common/erl_check_io.h
+++ b/erts/emulator/sys/common/erl_check_io.h
@@ -18,10 +18,11 @@
  * %CopyrightEnd%
  */
 
-/*
- * Description:	Check I/O
+/**
+ * @description Check I/O, a cross platform IO polling framework for ERTS
  *
- * Author: 	Rickard Green
+ * @author Rickard Green
+ * @author Lukas Larsson
  */
 
 #ifndef ERL_CHECK_IO_H__
@@ -30,79 +31,79 @@
 #include "sys.h"
 #include "erl_sys_driver.h"
 
-#ifdef ERTS_ENABLE_KERNEL_POLL
-
-int driver_select_kp(ErlDrvPort, ErlDrvEvent, int, int);
-int driver_select_nkp(ErlDrvPort, ErlDrvEvent, int, int);
-int enif_select_kp(ErlNifEnv*, ErlNifEvent, enum ErlNifSelectFlags, void*, const ErlNifPid*, Eterm);
-int enif_select_nkp(ErlNifEnv*, ErlNifEvent, enum ErlNifSelectFlags, void*, const ErlNifPid*, Eterm);
-int driver_event_kp(ErlDrvPort, ErlDrvEvent, ErlDrvEventData);
-int driver_event_nkp(ErlDrvPort, ErlDrvEvent, ErlDrvEventData);
-Uint erts_check_io_size_kp(void);
-Uint erts_check_io_size_nkp(void);
-Eterm erts_check_io_info_kp(void *);
-Eterm erts_check_io_info_nkp(void *);
-int erts_check_io_max_files_kp(void);
-int erts_check_io_max_files_nkp(void);
-#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
-void erts_check_io_async_sig_interrupt_kp(void);
-void erts_check_io_async_sig_interrupt_nkp(void);
-#endif
-void erts_check_io_interrupt_kp(int);
-void erts_check_io_interrupt_nkp(int);
-void erts_check_io_interrupt_timed_kp(int, ErtsMonotonicTime);
-void erts_check_io_interrupt_timed_nkp(int, ErtsMonotonicTime);
-void erts_check_io_kp(int);
-void erts_check_io_nkp(int);
-void erts_init_check_io_kp(void);
-void erts_init_check_io_nkp(void);
-int erts_check_io_debug_kp(ErtsCheckIoDebugInfo *);
-int erts_check_io_debug_nkp(ErtsCheckIoDebugInfo *);
-
-#ifdef ERTS_ENABLE_LOCK_COUNT
-void erts_lcnt_update_cio_locks_kp(int enable);
-void erts_lcnt_update_cio_locks_nkp(int enable);
-#endif
-
-#else /* !ERTS_ENABLE_KERNEL_POLL */
+/** @brief a structure that is used by each polling thread */
+struct erts_poll_thread;
 
+/**
+ * Get the memory size of the check io framework
+ */
 Uint erts_check_io_size(void);
-Eterm erts_check_io_info(void *);
+/**
+ * Returns an Eterm with information about all the pollsets active at the
+ * moment.
+ *
+ * @param proc the Process* to allocate the result on. It is passed as
+ *  void * because of header include problems.
+ */
+Eterm erts_check_io_info(void *proc);
+/**
+ * Should be called when a port IO task has been executed in order to re-enable
+ * or clear the information about the fd.
+ *
+ * @param type The type of event that has been completed.
+ * @param handle The port task handle of the event.
+ * @param reset A function pointer to be called when the port task handle
+ *  should be reset.
+ */
+void erts_io_notify_port_task_executed(ErtsPortTaskType type,
+                                       ErtsPortTaskHandle *handle,
+                                       void (*reset)(ErtsPortTaskHandle *));
+/**
+ * Returns the maximum number of fds that the check io framework can handle.
+ */
 int erts_check_io_max_files(void);
-#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
-void erts_check_io_async_sig_interrupt(void);
-#endif
-void erts_check_io_interrupt(int);
-void erts_check_io_interrupt_timed(int, ErtsMonotonicTime);
-void erts_check_io(int);
-void erts_init_check_io(void);
-
+/**
+ * Called by any thread that should check for new IO events. This function will
+ * not return unless erts_check_io_interrupt(pt, 1) is called by another thread.
+ *
+ * @param pt the poll thread structure to use.
+ */
+void erts_check_io(struct erts_poll_thread *pt);
+/**
+ * Initialize the check io framework. This function will parse the arguments
+ * and delete any entries that it is interested in.
+ *
+ * @param argc the number of arguments
+ * @param argv an array with the arguments
+ */
+void erts_init_check_io(int *argc, char **argv);
+/**
+ * Interrupt the poll thread so that it can execute other code.
+ *
+ * Should be called with set = 0 by the waiting thread before calling
+ * erts_check_io.
+ *
+ * @param pt the poll thread to wake
+ * @param set whether to set or clear the interrupt flag
+ */
+void erts_check_io_interrupt(struct erts_poll_thread *pt, int set);
+/**
+ * Create a new poll thread structure that is associated with the number no.
+ * It is the callers responsibility that no is unique.
+ */
+struct erts_poll_thread* erts_create_pollset_thread(int no);
 #ifdef ERTS_ENABLE_LOCK_COUNT
+/**
+ * Toggle lock counting on all check io locks
+ */
 void erts_lcnt_update_cio_locks(int enable);
 #endif
 
-#endif
-
-extern erts_smp_atomic_t erts_check_io_time;
-
 typedef struct {
     ErtsPortTaskHandle task;
-    erts_smp_atomic_t executed_time;
+    ErtsSysFdType fd;
 } ErtsIoTask;
 
-ERTS_GLB_INLINE void erts_io_notify_port_task_executed(ErtsPortTaskHandle *pthp);
-
-#if ERTS_GLB_INLINE_INCL_FUNC_DEF
-
-ERTS_GLB_INLINE void
-erts_io_notify_port_task_executed(ErtsPortTaskHandle *pthp)
-{
-    ErtsIoTask *itp = (ErtsIoTask *) (((char *) pthp) - offsetof(ErtsIoTask, task));
-    erts_aint_t ci_time = erts_smp_atomic_read_acqb(&erts_check_io_time);
-    erts_smp_atomic_set_relb(&itp->executed_time, ci_time);
-}
-
-#endif
 
 #endif /*  ERL_CHECK_IO_H__ */
 
@@ -110,6 +111,16 @@ erts_io_notify_port_task_executed(ErtsPortTaskHandle *pthp)
 #define ERL_CHECK_IO_INTERNAL__
 #endif
 
+#define ERTS_CHECK_IO_DRV_EV_STATE_LOCK_CNT 128
+
+/* Controls how many pollsets to allocate. Fd's are hashed into
+   each pollset based on the FD. When doing non-concurrent updates
+   there will be one pollset per thread.
+*/
+extern int erts_no_pollsets;
+extern int erts_no_poll_threads;
+
+
 #ifndef ERL_CHECK_IO_INTERNAL__
 #define ERL_CHECK_IO_INTERNAL__
 #include "erl_poll.h"
@@ -122,24 +133,8 @@ erts_io_notify_port_task_executed(ErtsPortTaskHandle *pthp)
  */
 #  define ERTS_CIO_DEFER_ACTIVE_EVENTS 1
 #else
-#  define ERTS_CIO_DEFER_ACTIVE_EVENTS 0
-#endif
-
-/*
- * ErtsDrvEventDataState is used by driver_event() which is almost never
- * used. We allocate ErtsDrvEventDataState separate since we dont wan't
- * the size of ErtsDrvEventState to increase due to driver_event()
- * information.
- */
-typedef struct {
-    Eterm port;
-    ErlDrvEventData data;
-    ErtsPollEvents removed_events;
-#if ERTS_CIO_DEFER_ACTIVE_EVENTS
-    ErtsPollEvents deferred_events;
+#  define ERTS_CIO_DEFER_ACTIVE_EVENTS 1
 #endif
-    ErtsIoTask iotask;
-} ErtsDrvEventDataState;
 
 typedef struct {
     Eterm inport;
diff --git a/erts/emulator/sys/common/erl_mmap.c b/erts/emulator/sys/common/erl_mmap.c
index 214ed01c82..a9c6e72c5f 100644
--- a/erts/emulator/sys/common/erl_mmap.c
+++ b/erts/emulator/sys/common/erl_mmap.c
@@ -24,7 +24,6 @@
 #define ERTS_WANT_MEM_MAPPERS
 #include "sys.h"
 #include "erl_process.h"
-#include "erl_smp.h"
 #include "atom.h"
 #include "erl_mmap.h"
 #include <stddef.h>
@@ -62,11 +61,11 @@
     (((UWord) (PTR)) - ((UWord) mm->sa.bot)			\
      < ((UWord) mm->sua.top) - ((UWord) mm->sa.bot))
 #define ERTS_MMAP_IN_SUPERALIGNED_AREA(PTR)				\
-    (ERTS_SMP_LC_ASSERT(erts_lc_mtx_is_locked(&mm->mtx)),	\
+    (ERTS_LC_ASSERT(erts_lc_mtx_is_locked(&mm->mtx)),	\
      (((UWord) (PTR)) - ((UWord) mm->sa.bot)			\
       < ((UWord) mm->sa.top) - ((UWord) mm->sa.bot)))
 #define ERTS_MMAP_IN_SUPERUNALIGNED_AREA(PTR)				\
-    (ERTS_SMP_LC_ASSERT(erts_lc_mtx_is_locked(&mm->mtx)),	\
+    (ERTS_LC_ASSERT(erts_lc_mtx_is_locked(&mm->mtx)),	\
      (((UWord) (PTR)) - ((UWord) mm->sua.bot)			\
       < ((UWord) mm->sua.top) - ((UWord) mm->sua.bot)))
 
@@ -199,10 +198,10 @@ static ErtsMMapOp mmap_ops[ERTS_MMAP_OP_RINGBUF_SZ];
 
 #define ERTS_MMAP_OP_LCK(RES, IN_SZ, OUT_SZ)			\
     do {							\
-	erts_smp_mtx_lock(&mm->mtx);			\
+	erts_mtx_lock(&mm->mtx);			\
 	ERTS_MMAP_OP_START((IN_SZ));				\
 	ERTS_MMAP_OP_END((RES), (OUT_SZ));			\
-	erts_smp_mtx_unlock(&mm->mtx);			\
+	erts_mtx_unlock(&mm->mtx);			\
     } while (0)
 
 #define ERTS_MUNMAP_OP(PTR, SZ)					\
@@ -221,9 +220,9 @@ static ErtsMMapOp mmap_ops[ERTS_MMAP_OP_RINGBUF_SZ];
 
 #define ERTS_MUNMAP_OP_LCK(PTR, SZ)				\
     do {							\
-	erts_smp_mtx_lock(&mm->mtx);			\
+	erts_mtx_lock(&mm->mtx);			\
 	ERTS_MUNMAP_OP((PTR), (SZ));				\
-	erts_smp_mtx_unlock(&mm->mtx);			\
+	erts_mtx_unlock(&mm->mtx);			\
     } while (0)
 
 #define ERTS_MREMAP_OP_START(OLD_PTR, OLD_SZ, IN_SZ)		\
@@ -249,10 +248,10 @@ static ErtsMMapOp mmap_ops[ERTS_MMAP_OP_RINGBUF_SZ];
 
 #define ERTS_MREMAP_OP_LCK(RES, OLD_PTR, OLD_SZ, IN_SZ, OUT_SZ)	\
     do {							\
-	erts_smp_mtx_lock(&mm->mtx);			\
+	erts_mtx_lock(&mm->mtx);			\
 	ERTS_MREMAP_OP_START((OLD_PTR), (OLD_SZ), (IN_SZ));	\
 	ERTS_MREMAP_OP_END((RES), (OUT_SZ));			\
-	erts_smp_mtx_unlock(&mm->mtx);			\
+	erts_mtx_unlock(&mm->mtx);			\
     } while (0)
 
 #define ERTS_MMAP_OP_ABORT()					\
@@ -321,7 +320,7 @@ struct ErtsMemMapper_ {
 #if HAVE_MMAP && (!defined(MAP_ANON) && !defined(MAP_ANONYMOUS))
     int mmap_fd;
 #endif
-    erts_smp_mtx_t mtx;
+    erts_mtx_t mtx;
     struct {
 	char *free_list;
 	char *unused_start;
@@ -1536,7 +1535,7 @@ erts_mmap(ErtsMemMapper* mm, Uint32 flags, UWord *sizep)
 	ErtsFreeSegDesc *desc;
 	Uint32 superaligned = (ERTS_MMAPFLG_SUPERALIGNED & flags);
 
-	erts_smp_mtx_lock(&mm->mtx);
+	erts_mtx_lock(&mm->mtx);
 
 	ERTS_MMAP_OP_START(*sizep);
 
@@ -1660,7 +1659,7 @@ erts_mmap(ErtsMemMapper* mm, Uint32 flags, UWord *sizep)
 	}
 
 	ERTS_MMAP_OP_ABORT();
-	erts_smp_mtx_unlock(&mm->mtx);
+	erts_mtx_unlock(&mm->mtx);
     }
 
 #if ERTS_HAVE_OS_MMAP
@@ -1724,13 +1723,13 @@ supercarrier_success:
 #endif
 
     ERTS_MMAP_OP_END(seg, asize);
-    erts_smp_mtx_unlock(&mm->mtx);
+    erts_mtx_unlock(&mm->mtx);
 
     *sizep = asize;
     return (void *) seg;
 
 supercarrier_reserve_failure:
-    erts_smp_mtx_unlock(&mm->mtx);
+    erts_mtx_unlock(&mm->mtx);
     *sizep = 0;
     return NULL;
 }
@@ -1760,7 +1759,7 @@ erts_munmap(ErtsMemMapper* mm, Uint32 flags, void *ptr, UWord size)
 	start = (char *) ptr;
 	end = start + size;
 
-	erts_smp_mtx_lock(&mm->mtx);
+	erts_mtx_lock(&mm->mtx);
 
 	ERTS_MUNMAP_OP(ptr, size);
 
@@ -1829,7 +1828,7 @@ erts_munmap(ErtsMemMapper* mm, Uint32 flags, void *ptr, UWord size)
 	    if (unres_sz)
 		mm->unreserve_physical(((char *) ptr) + ad_sz, unres_sz);
 
-            erts_smp_mtx_unlock(&mm->mtx);
+            erts_mtx_unlock(&mm->mtx);
 	}
     }
 }
@@ -1948,12 +1947,12 @@ erts_mremap(ErtsMemMapper* mm,
 		 ? ERTS_SUPERALIGNED_CEILING(*sizep)
 		 : ERTS_PAGEALIGNED_CEILING(*sizep));
 
-	erts_smp_mtx_lock(&mm->mtx);
+	erts_mtx_lock(&mm->mtx);
 
 	if (ERTS_MMAP_IN_SUPERALIGNED_AREA(ptr)
 	    ? (!superaligned && lookup_free_seg(&mm->sua.map, asize))
 	    : (superaligned && lookup_free_seg(&mm->sa.map, asize))) {
-	    erts_smp_mtx_unlock(&mm->mtx);
+	    erts_mtx_unlock(&mm->mtx);
 	    /*
 	     * Segment currently in wrong area (due to a previous memory
 	     * shortage), move it to the right area.
@@ -2068,7 +2067,7 @@ erts_mremap(ErtsMemMapper* mm,
 	}
 
 	ERTS_MMAP_OP_ABORT();
-	erts_smp_mtx_unlock(&mm->mtx);
+	erts_mtx_unlock(&mm->mtx);
 
 	/* Failed to resize... */
     }
@@ -2090,14 +2089,14 @@ supercarrier_resize_success:
 #endif
 
     ERTS_MREMAP_OP_END(new_ptr, asize);
-    erts_smp_mtx_unlock(&mm->mtx);
+    erts_mtx_unlock(&mm->mtx);
 
     *sizep = asize;
     return new_ptr;
 
 supercarrier_reserve_failure:
     ERTS_MREMAP_OP_END(NULL, old_size);
-    erts_smp_mtx_unlock(&mm->mtx);
+    erts_mtx_unlock(&mm->mtx);
     *sizep = old_size;
     return NULL;
     
@@ -2212,7 +2211,7 @@ erts_mmap_init(ErtsMemMapper* mm, ErtsMMapInit *init, int executable)
 	erts_exit(1, "erts_mmap: Failed to open /dev/zero\n");
 #endif
 
-    erts_smp_mtx_init(&mm->mtx, "erts_mmap", NIL,
+    erts_mtx_init(&mm->mtx, "erts_mmap", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
     if (is_first_call) {
         erts_mtx_init(&am.init_mutex, "mmap_init_atoms", NIL,
@@ -2407,7 +2406,7 @@ Eterm erts_mmap_info(ErtsMemMapper* mm,
     Eterm res = THE_NON_VALUE;
 
     if (!hpp) {
-        erts_smp_mtx_lock(&mm->mtx);
+        erts_mtx_lock(&mm->mtx);
         emis->sizes[0] = mm->size.supercarrier.total;
         emis->sizes[1] = mm->sa.top  - mm->sa.bot;
         emis->sizes[2] = mm->sua.top - mm->sua.bot;
@@ -2423,7 +2422,7 @@ Eterm erts_mmap_info(ErtsMemMapper* mm,
         emis->segs[5] = mm->sua.map.nseg;
 
         emis->os_used = mm->size.os.used;
-        erts_smp_mtx_unlock(&mm->mtx);
+        erts_mtx_unlock(&mm->mtx);
     }
 
     list[lix] = erts_mmap_info_options(mm, "option ", print_to_p, print_to_arg,
@@ -2543,14 +2542,14 @@ Eterm erts_mmap_debug_info(Process* p)
         Eterm *hp, *hp_end;
         Uint may_need;
 
-        erts_smp_mtx_lock(&mm->mtx);
+        erts_mtx_lock(&mm->mtx);
         values[0] = (UWord)mm->sa.bot;
         values[1] = (UWord)mm->sa.top;
         values[2] = (UWord)mm->sua.bot;
         values[3] = (UWord)mm->sua.top;
         sa_list = build_free_seg_list(p, &mm->sa.map);
         sua_list = build_free_seg_list(p, &mm->sua.map);
-        erts_smp_mtx_unlock(&mm->mtx);
+        erts_mtx_unlock(&mm->mtx);
 
         may_need = 4*(2+3+2) + 2*(2+3);
         hp = HAlloc(p, may_need);
diff --git a/erts/emulator/sys/common/erl_mseg.c b/erts/emulator/sys/common/erl_mseg.c
index d69a79dc2a..bf6de9b13a 100644
--- a/erts/emulator/sys/common/erl_mseg.c
+++ b/erts/emulator/sys/common/erl_mseg.c
@@ -188,7 +188,6 @@ typedef union {
 static int no_mseg_allocators;
 static ErtsAlgndMsegAllctr_t *aligned_mseg_allctr;
 
-#ifdef ERTS_SMP
 
 #define ERTS_MSEG_ALLCTR_IX(IX) \
   (&aligned_mseg_allctr[(IX)].mseg_alloc)
@@ -199,18 +198,6 @@ static ErtsAlgndMsegAllctr_t *aligned_mseg_allctr;
 #define ERTS_MSEG_ALLCTR_OPT(OPT) \
   ((OPT)->sched_spec ? ERTS_MSEG_ALLCTR_SS() : ERTS_MSEG_ALLCTR_IX(0))
 
-#else
-
-#define ERTS_MSEG_ALLCTR_IX(IX) \
-  (&aligned_mseg_allctr[0].mseg_alloc)
-
-#define ERTS_MSEG_ALLCTR_SS() \
-  (&aligned_mseg_allctr[0].mseg_alloc)
-
-#define ERTS_MSEG_ALLCTR_OPT(OPT) \
-  (&aligned_mseg_allctr[0].mseg_alloc)
-
-#endif
 
 #define ERTS_MSEG_LOCK(MA)		\
 do {					\
@@ -352,11 +339,11 @@ mseg_recreate(ErtsMsegAllctr_t *ma, Uint flags, void *old_seg, UWord old_size, U
 do {									\
     if ((MA)->is_thread_safe)						\
 	ERTS_LC_ASSERT(erts_lc_mtx_is_locked(&(MA)->mtx)		\
-		       || erts_smp_thr_progress_is_blocking()		\
+		       || erts_thr_progress_is_blocking()		\
 		       || ERTS_IS_CRASH_DUMPING);			\
     else								\
 	ERTS_LC_ASSERT((MA)->ix == (int) erts_get_scheduler_id()	\
-		       || erts_smp_thr_progress_is_blocking()		\
+		       || erts_thr_progress_is_blocking()		\
 		       || ERTS_IS_CRASH_DUMPING);			\
 } while (0)
 #else
@@ -1404,11 +1391,7 @@ erts_mseg_init(ErtsMsegInit_t *init)
     int i;
     UWord x;
 
-#ifdef ERTS_SMP
     no_mseg_allocators = init->nos + 1;
-#else
-    no_mseg_allocators = 1;
-#endif
 
     x = (UWord) malloc(sizeof(ErtsAlgndMsegAllctr_t)
 		       *no_mseg_allocators
diff --git a/erts/emulator/sys/common/erl_os_monotonic_time_extender.c b/erts/emulator/sys/common/erl_os_monotonic_time_extender.c
index d53190fdd5..341845cc2a 100644
--- a/erts/emulator/sys/common/erl_os_monotonic_time_extender.c
+++ b/erts/emulator/sys/common/erl_os_monotonic_time_extender.c
@@ -23,7 +23,6 @@
 #endif
 #include "erl_os_monotonic_time_extender.h"
 
-#ifdef USE_THREADS
 
 static void *os_monotonic_time_extender(void *vstatep)
 {
@@ -49,30 +48,22 @@ static void *os_monotonic_time_extender(void *vstatep)
 }
 
 static erts_tid_t os_monotonic_extender_tid;
-#endif
 
 void
 erts_init_os_monotonic_time_extender(ErtsOsMonotonicTimeExtendState *statep,
 				     Uint32 (*raw_os_monotonic_time)(void),
 				     int check_seconds)
 {
-#ifdef USE_THREADS
     statep->raw_os_monotonic_time = raw_os_monotonic_time;
     erts_atomic32_init_nob(&statep->extend[0], (erts_aint32_t) 0);
     erts_atomic32_init_nob(&statep->extend[1], (erts_aint32_t) 0);
     statep->check_interval = check_seconds;
 
-#else
-    statep->extend[0] = (Uint32) 0;
-    statep->extend[1] = (Uint32) 0;
-    statep->last_msb = (ErtsMonotonicTime) 0;
-#endif
 }
 
 void
 erts_late_init_os_monotonic_time_extender(ErtsOsMonotonicTimeExtendState *statep)
 {
-#ifdef USE_THREADS
     erts_thr_opts_t thr_opts = ERTS_THR_OPTS_DEFAULT_INITER;
     thr_opts.detached = 1;
     thr_opts.suggested_stack_size = 4;
@@ -85,5 +76,4 @@ erts_late_init_os_monotonic_time_extender(ErtsOsMonotonicTimeExtendState *statep
 		    os_monotonic_time_extender,
 		    (void*) statep,
 		    &thr_opts);
-#endif
 }
diff --git a/erts/emulator/sys/common/erl_os_monotonic_time_extender.h b/erts/emulator/sys/common/erl_os_monotonic_time_extender.h
index 8089c9aed9..53c32579d5 100644
--- a/erts/emulator/sys/common/erl_os_monotonic_time_extender.h
+++ b/erts/emulator/sys/common/erl_os_monotonic_time_extender.h
@@ -25,36 +25,16 @@
 #include "erl_threads.h"
 
 typedef struct {
-#ifdef USE_THREADS
     Uint32 (*raw_os_monotonic_time)(void);
     erts_atomic32_t extend[2];
     int check_interval;
-#else
-    Uint32 extend[2];
-    ErtsMonotonicTime last_msb;
-#endif
 } ErtsOsMonotonicTimeExtendState;
 
-#ifdef USE_THREADS
-#  define ERTS_CHK_EXTEND_OS_MONOTONIC_TIME(S, RT) ((void) 1)
 #  define ERTS_EXTEND_OS_MONOTONIC_TIME(S, RT)				\
     ((((ErtsMonotonicTime)						\
        erts_atomic32_read_nob(&((S)->extend[((int) ((RT) >> 31)) & 1]))) \
       << 32)								\
      + (RT))
-#else
-#  define ERTS_CHK_EXTEND_OS_MONOTONIC_TIME(S, RT)			\
-    do {								\
-	Uint32 msb__ = (RT) & (((Uint32) 1) << 31);			\
-	if (msb__ != (S)->last_msb) {					\
-	    int ix__ = ((int) ((S)->last_msb >> 31)) & 1;		\
-	    (S)->extend[ix__]++;					\
-	    (S)->last_msb = msb;					\
-	}								\
-    } while (0)
-#  define ERTS_EXTEND_OS_MONOTONIC_TIME(S, RT)				\
-    ((((ErtsMonotonicTime) (S)->extend[((int) ((RT) >> 31)) & 1]) << 32) + (RT))
-#endif
 
 void
 erts_init_os_monotonic_time_extender(ErtsOsMonotonicTimeExtendState *statep,
diff --git a/erts/emulator/sys/common/erl_poll.c b/erts/emulator/sys/common/erl_poll.c
index 52a8b6a53f..7aa53e8f36 100644
--- a/erts/emulator/sys/common/erl_poll.c
+++ b/erts/emulator/sys/common/erl_poll.c
@@ -18,9 +18,8 @@
  * %CopyrightEnd%
  */
 
-/*
- * Description:	Poll interface suitable for ERTS with or without
- *              SMP support.
+/**
+ * @description Poll interface suitable for ERTS
  *
  *		The interface is currently implemented using:
  *		- select
@@ -29,12 +28,36 @@
  *              - epoll with poll or select as fallback
  *              - kqueue with poll or select as fallback
  *
- *		Some time in the future it will also be
- *		implemented using Solaris ports.
  *
+ * @author Rickard Green
+ * @author Lukas Larsson
+ *
+ * There are two major different implementations off IO polling in this
+ * file. The concurrent and non-concurrent implementations.
+ * When available epoll/kqueue are used to implement the concurrent
+ * versions. poll, select and dev/poll use non-concurrent updates.
+ *
+ * Concurrent version:
+ *   In the concurrent version erts_poll_control directly modifies
+ *   the kernel pollset without waking the thread that is waiting
+ *   on events. Also the ErtsPollResFd type is directly mapped to
+ *   the native event type, so no extra copying is needed. Note that
+ *   as no locking at all is done, fds can be triggered that have been
+ *   removed from the pollset. The check_io layer has to deal with this.
+ *
+ * Non-concurrent version:
+ *   In the non-concurrent version, the pollset has an internal representation
+ *   of the pollset that is updated by erts_poll_control. When an fd is updated,
+ *   its number is placed in the update request queue and then the waiting thread
+ *   is woken in order to see the change. The internal data in the pollset is
+ *   protected by a mutex that has to be taken by both the modifying and waiting
+ *   thread at different times.
  *
+ *   The non-concurrent pollset cannot have fd's closed in it while a thread is
+ *   waiting on that fd. In order to fix this, when an ERTS_POLL_OP_DEL command
+ *   is issued, the fd is marked as closing and the waiting thread is woken. The
+ *   fd is then returned in the waiting threads results as ERTS_POLL_EV_NONE.
  *
- * Author: 	Rickard Green
  */
 
 #ifdef HAVE_CONFIG_H
@@ -62,6 +85,8 @@
 #  ifdef SYS_SELECT_H
 #    include <sys/select.h>
 #  endif
+#elif defined(_DARWIN_UNLIMITED_SELECT)
+#  undef _DARWIN_UNLIMITED_SELECT
 #endif
 #ifdef NO_SYSCONF
 #  if ERTS_POLL_USE_SELECT
@@ -83,23 +108,35 @@
 #error "Missing implementation of erts_poll()"
 #endif
 
-#if defined(ERTS_KERNEL_POLL_VERSION) && !ERTS_POLL_USE_KERNEL_POLL
-#error "Missing kernel poll implementation of erts_poll()"
-#endif
+#if 0
+#define ERTS_POLL_DEBUG_PRINT 1
 
-#if defined(ERTS_NO_KERNEL_POLL_VERSION) && ERTS_POLL_USE_KERNEL_POLL
-#error "Kernel poll used when it shouldn't be used"
-#endif
+#define DEBUG_PRINT(FMT, PS, ...)                                       \
+    do {                                                                \
+        int myerrno = errno;                                            \
+        erts_printf("%d: " FMT "\r\n", (PS)->id, ##__VA_ARGS__);        \
+        errno = myerrno;                                                \
+    } while(0)
 
-#if 0
-#define ERTS_POLL_DEBUG_PRINT
+/* Define to print info about modifications done to each fd */
+#define DEBUG_PRINT_FD(FMT, PS, FD, ...) DEBUG_PRINT("%d: " FMT, PS, FD, ##__VA_ARGS__)
+/* Define to print entry and exit from erts_poll_wait (can be very spammy) */
+//#define DEBUG_PRINT_WAIT(FMT, PS, ...) DEBUG_PRINT(FMT, PS, ##__VA_ARGS__)
+
+#else
+#define ERTS_POLL_DEBUG_PRINT 0
+#define DEBUG_PRINT(...)
 #endif
 
-#if defined(DEBUG) && 0
-#define HARD_DEBUG
+#ifndef DEBUG_PRINT_FD
+#define DEBUG_PRINT_FD(...)
+#endif
+#ifndef DEBUG_PRINT_WAIT
+#define DEBUG_PRINT_WAIT(...)
 #endif
 
-#ifdef _DARWIN_UNLIMITED_SELECT
+
+#if defined(_DARWIN_UNLIMITED_SELECT) && ERTS_POLL_USE_SELECT
 typedef struct {
     size_t sz;
     fd_set* ptr;
@@ -145,74 +182,43 @@ int ERTS_SELECT(int nfds, ERTS_fd_set *readfds, ERTS_fd_set *writefds,
 #  define ERTS_SELECT	select
 #endif
 
-#define ERTS_POLL_USE_BATCH_UPDATE_POLLSET (ERTS_POLL_USE_DEVPOLL \
-					    || ERTS_POLL_USE_KQUEUE)
-#define ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE \
-   (defined(ERTS_SMP) || ERTS_POLL_USE_KERNEL_POLL || ERTS_POLL_USE_POLL)
+#define ERTS_POLL_IS_FALLBACK (ERTS_POLL_USE_POLL || ERTS_POLL_USE_SELECT) && ERTS_ENABLE_KERNEL_POLL
 
-#define ERTS_POLL_USE_CONCURRENT_UPDATE \
-   (defined(ERTS_SMP) && ERTS_POLL_USE_EPOLL)
+#define ERTS_POLL_USE_CONCURRENT_UPDATE (ERTS_POLL_USE_EPOLL || ERTS_POLL_USE_KQUEUE)
 
-#define ERTS_POLL_COALESCE_KP_RES (ERTS_POLL_USE_KQUEUE || ERTS_POLL_USE_EPOLL)
+#define ERTS_POLL_USE_WAKEUP_PIPE (!ERTS_POLL_USE_CONCURRENT_UPDATE)
 
-#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
-#  define ERTS_POLL_ASYNC_INTERRUPT_SUPPORT 1
-#else
-#  define ERTS_POLL_ASYNC_INTERRUPT_SUPPORT 0
-#endif
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
 
-#define ERTS_POLL_USE_WAKEUP_PIPE \
-   (ERTS_POLL_ASYNC_INTERRUPT_SUPPORT || defined(USE_THREADS))
-
-#ifdef ERTS_SMP
+#define ERTS_POLLSET_SET_HAVE_UPDATE_REQUESTS(PS) \
+  erts_atomic32_set_nob(&(PS)->have_update_requests, (erts_aint32_t) 1)
+#define ERTS_POLLSET_UNSET_HAVE_UPDATE_REQUESTS(PS) \
+  erts_atomic32_set_nob(&(PS)->have_update_requests, (erts_aint32_t) 0)
+#define ERTS_POLLSET_HAVE_UPDATE_REQUESTS(PS) \
+  ((int) erts_atomic32_read_nob(&(PS)->have_update_requests))
 
 #define ERTS_POLLSET_LOCK(PS) \
-  erts_smp_mtx_lock(&(PS)->mtx)
+  erts_mtx_lock(&(PS)->mtx)
 #define ERTS_POLLSET_UNLOCK(PS) \
-  erts_smp_mtx_unlock(&(PS)->mtx)
-
-#define ERTS_POLLSET_SET_POLLED_CHK(PS) \
-  ((int) erts_atomic32_xchg_nob(&(PS)->polled, (erts_aint32_t) 1))
-#define ERTS_POLLSET_UNSET_POLLED(PS) \
-  erts_atomic32_set_nob(&(PS)->polled, (erts_aint32_t) 0)
-#define ERTS_POLLSET_IS_POLLED(PS) \
-  ((int) erts_atomic32_read_nob(&(PS)->polled))
+  erts_mtx_unlock(&(PS)->mtx)
 
 #else
 
-#define ERTS_POLLSET_LOCK(PS)
-#define ERTS_POLLSET_UNLOCK(PS)
-#define ERTS_POLLSET_SET_POLLED_CHK(PS) 0
-#define ERTS_POLLSET_UNSET_POLLED(PS)
-#define ERTS_POLLSET_IS_POLLED(PS) 0
-
-#endif
-
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
-#define ERTS_POLLSET_SET_HAVE_UPDATE_REQUESTS(PS) \
-  erts_smp_atomic32_set_nob(&(PS)->have_update_requests, (erts_aint32_t) 1)
-#define ERTS_POLLSET_UNSET_HAVE_UPDATE_REQUESTS(PS) \
-  erts_smp_atomic32_set_nob(&(PS)->have_update_requests, (erts_aint32_t) 0)
-#define ERTS_POLLSET_HAVE_UPDATE_REQUESTS(PS) \
-  ((int) erts_smp_atomic32_read_nob(&(PS)->have_update_requests))
-#else
 #define ERTS_POLLSET_SET_HAVE_UPDATE_REQUESTS(PS)
 #define ERTS_POLLSET_UNSET_HAVE_UPDATE_REQUESTS(PS)
 #define ERTS_POLLSET_HAVE_UPDATE_REQUESTS(PS) 0
-#endif
 
-#if ERTS_POLL_USE_FALLBACK
-#  if ERTS_POLL_USE_POLL
-#    define ERTS_POLL_NEED_FALLBACK(PS) ((PS)->no_poll_fds > 1)
-#  elif ERTS_POLL_USE_SELECT
-#    define ERTS_POLL_NEED_FALLBACK(PS) ((PS)->no_select_fds > 1)
-#  endif
+#define ERTS_POLLSET_LOCK(PS)
+#define ERTS_POLLSET_UNLOCK(PS)
+
 #endif
+
 /*
  * --- Data types ------------------------------------------------------------
  */
 
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
+
 #define ERTS_POLLSET_UPDATE_REQ_BLOCK_SIZE 128
 
 typedef struct ErtsPollSetUpdateRequestsBlock_ ErtsPollSetUpdateRequestsBlock;
@@ -222,206 +228,146 @@ struct ErtsPollSetUpdateRequestsBlock_ {
     int fds[ERTS_POLLSET_UPDATE_REQ_BLOCK_SIZE];
 };
 
-#endif
-
-
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
 #  define ERTS_POLL_FD_FLG_INURQ	(((unsigned short) 1) << 0)
-#endif
-#if ERTS_POLL_USE_FALLBACK
-#  define ERTS_POLL_FD_FLG_INFLBCK	(((unsigned short) 1) << 1)
-#  define ERTS_POLL_FD_FLG_USEFLBCK	(((unsigned short) 1) << 2)
-#endif
-#if ERTS_POLL_USE_KERNEL_POLL || defined(ERTS_SMP)
-#  define ERTS_POLL_FD_FLG_RST		(((unsigned short) 1) << 3)
-#endif
+#  define ERTS_POLL_FD_FLG_RST		(((unsigned short) 1) << 1)
+
 typedef struct {
 #if ERTS_POLL_USE_POLL
     int pix;
 #endif
+
     ErtsPollEvents used_events;
     ErtsPollEvents events;
-#if ERTS_POLL_COALESCE_KP_RES
-    unsigned short res_ev_ix;
-#endif
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE || ERTS_POLL_USE_FALLBACK
     unsigned short flags;
-#endif
 
 } ErtsFdStatus;
 
-
-#if ERTS_POLL_COALESCE_KP_RES
-/* res_ev_ix max value */
-#define ERTS_POLL_MAX_RES ((1 << sizeof(unsigned short)*8) - 1)
-#endif
-
-#if ERTS_POLL_USE_KQUEUE
-
-#define ERTS_POLL_KQ_OP_HANDLED			1
-#define ERTS_POLL_KQ_OP_DEL_R			2
-#define ERTS_POLL_KQ_OP_DEL_W			3
-#define ERTS_POLL_KQ_OP_ADD_R			4
-#define ERTS_POLL_KQ_OP_ADD_W			5
-#define ERTS_POLL_KQ_OP_ADD2_R			6
-#define ERTS_POLL_KQ_OP_ADD2_W			7
-
 #endif
 
-struct ErtsPollSet_ {
-    ErtsPollSet next;
+/*
+ * This struct is not really exported, but it's nice to
+ * get unique names in debugger for kp/nkp
+ */
+struct ERTS_POLL_EXPORT(erts_pollset) {
+    int id;
     int internal_fd_limit;
-    ErtsFdStatus *fds_status;
-    erts_smp_atomic_t no_of_user_fds;
-    int fds_status_len;
+    erts_atomic_t no_of_user_fds;
+
 #if ERTS_POLL_USE_KERNEL_POLL
     int kp_fd;
-    int res_events_len;
-#if ERTS_POLL_USE_EPOLL
-    struct epoll_event *res_events;
-#elif ERTS_POLL_USE_KQUEUE
-    struct kevent *res_events;
-#elif ERTS_POLL_USE_DEVPOLL
-    struct pollfd *res_events;
-#endif
 #endif /* ERTS_POLL_USE_KERNEL_POLL */
+
 #if ERTS_POLL_USE_POLL
     int next_poll_fds_ix;
     int no_poll_fds;
     int poll_fds_len;
-    struct pollfd*poll_fds;
+    struct pollfd *poll_fds;
 #elif ERTS_POLL_USE_SELECT
     int next_sel_fd;
     int max_fd;
-#if ERTS_POLL_USE_FALLBACK
-    int no_select_fds;
-#endif
     ERTS_fd_set input_fds;
     ERTS_fd_set res_input_fds;
     ERTS_fd_set output_fds;
     ERTS_fd_set res_output_fds;
+#elif ERTS_POLL_USE_DEVPOLL
+    struct pollfd *poll_fds;
+    int poll_fds_ix;
 #endif
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
+
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
+    ErtsFdStatus *fds_status;
+    int fds_status_len;
     ErtsPollSetUpdateRequestsBlock update_requests;
     ErtsPollSetUpdateRequestsBlock *curr_upd_req_block;
-    erts_smp_atomic32_t have_update_requests;
-#endif
-#ifdef ERTS_SMP
-    erts_atomic32_t polled;
-    erts_smp_mtx_t mtx;
+    erts_atomic32_t have_update_requests;
+    erts_mtx_t mtx;
+    erts_atomic32_t wakeup_state;
 #endif
+
 #if ERTS_POLL_USE_WAKEUP_PIPE
     int wake_fds[2];
 #endif
-#if ERTS_POLL_USE_TIMERFD
-    int timer_fd;
-#endif
-#if ERTS_POLL_USE_FALLBACK
-    int fallback_used;
-#endif
-#if defined(USE_THREADS) || ERTS_POLL_ASYNC_INTERRUPT_SUPPORT
-    erts_atomic32_t wakeup_state;
-#endif
-    erts_atomic64_t timeout_time;
-#ifdef ERTS_POLL_COUNT_AVOIDED_WAKEUPS
-    erts_smp_atomic_t no_avoided_wakeups;
-    erts_smp_atomic_t no_avoided_interrupts;
-    erts_smp_atomic_t no_interrupt_timed;
-#endif
 };
 
 void erts_silence_warn_unused_result(long unused);
 static void fatal_error(char *format, ...);
-static void fatal_error_async_signal_safe(char *error_str);
 
 static int max_fds = -1;
-static ErtsPollSet pollsets;
-static erts_smp_mtx_t pollsets_lock;
 
 #if ERTS_POLL_USE_POLL
 
+#if !ERTS_POLL_IS_FALLBACK
+static ERTS_INLINE short ev2pollev(ErtsPollEvents ev)
+{
+    return ERTS_POLL_EV_E2N(ev);
+}
+
+static ERTS_INLINE ErtsPollEvents pollev2ev(short ev)
+{
+    return ERTS_POLL_EV_N2E(ev);
+}
+
+#else /* ERTS_POLL_IS_FALLBACK */
+
 static ERTS_INLINE short
 ev2pollev(ErtsPollEvents ev)
 {
-#if !ERTS_POLL_USE_FALLBACK || ERTS_POLL_USE_KQUEUE
-    return ERTS_POLL_EV_E2N(ev);
-#else /* Note, we only map events we are interested in */
     short res_ev = (short) 0;
     if (ev & ERTS_POLL_EV_IN)
-	res_ev |= ERTS_POLL_EV_NKP_IN;
+       res_ev |= ERTS_POLL_EV_NKP_IN;
     if (ev & ERTS_POLL_EV_OUT)
-	res_ev |= ERTS_POLL_EV_NKP_OUT;
+       res_ev |= ERTS_POLL_EV_NKP_OUT;
     return res_ev;
-#endif
 }
 
 static ERTS_INLINE ErtsPollEvents
 pollev2ev(short ev)
 {
-#if !ERTS_POLL_USE_FALLBACK || ERTS_POLL_USE_KQUEUE
-    return ERTS_POLL_EV_N2E(ev);
-#else /* Note, we only map events we are interested in */
     ErtsPollEvents res_ev = (ErtsPollEvents) 0;
     if (ev & ERTS_POLL_EV_NKP_IN)
-	res_ev |= ERTS_POLL_EV_IN;
+       res_ev |= ERTS_POLL_EV_IN;
     if (ev & ERTS_POLL_EV_NKP_OUT)
-	res_ev |= ERTS_POLL_EV_OUT;
+       res_ev |= ERTS_POLL_EV_OUT;
     if (ev & ERTS_POLL_EV_NKP_ERR)
-	res_ev |= ERTS_POLL_EV_ERR;
+       res_ev |= ERTS_POLL_EV_ERR;
     if (ev & ERTS_POLL_EV_NKP_NVAL)
-	res_ev |= ERTS_POLL_EV_NVAL;
-    return res_ev;
-#endif
+       res_ev |= ERTS_POLL_EV_NVAL;
+   return res_ev;
 }
 
-#endif
+#endif /* !ERTS_POLL_IS_FALLBACK */
+
+#endif /* ERTS_POLL_USE_POLL */
+
 
 #ifdef HARD_DEBUG
 static void check_poll_result(ErtsPollResFd pr[], int len);
-#if ERTS_POLL_USE_DEVPOLL
-static void check_poll_status(ErtsPollSet ps);
-#endif /* ERTS_POLL_USE_DEVPOLL */
 #endif /* HARD_DEBUG */
-#ifdef ERTS_POLL_DEBUG_PRINT
+#if ERTS_POLL_USE_DEVPOLL && defined(DEBUG)
+static void check_poll_status(ErtsPollSet *ps);
+#endif /* ERTS_POLL_USE_DEVPOLL && DEBUG */
 static void print_misc_debug_info(void);
+#if ERTS_POLL_USE_EPOLL
+uint32_t epoll_events(int kp_fd, int fd);
 #endif
 
-static ERTS_INLINE void
-init_timeout_time(ErtsPollSet ps)
-{
-    erts_atomic64_init_nob(&ps->timeout_time,
-			   (erts_aint64_t) ERTS_MONOTONIC_TIME_MAX);
-}
-
-static ERTS_INLINE void
-set_timeout_time(ErtsPollSet ps, ErtsMonotonicTime time)
-{
-    erts_atomic64_set_relb(&ps->timeout_time,
-			   (erts_aint64_t) time);
-}
-
-static ERTS_INLINE ErtsMonotonicTime
-get_timeout_time(ErtsPollSet ps)
-{
-    return (ErtsMonotonicTime) erts_atomic64_read_acqb(&ps->timeout_time);
-}
 
 #define ERTS_POLL_NOT_WOKEN	0
 #define ERTS_POLL_WOKEN		-1
 #define ERTS_POLL_WOKEN_INTR	1
 
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
 static ERTS_INLINE void
-reset_wakeup_state(ErtsPollSet ps)
+reset_wakeup_state(ErtsPollSet *ps)
 {
-#if defined(USE_THREADS) || ERTS_POLL_ASYNC_INTERRUPT_SUPPORT
     erts_atomic32_set_mb(&ps->wakeup_state, ERTS_POLL_NOT_WOKEN);
-#endif
 }
+#endif
 
 static ERTS_INLINE int
-is_woken(ErtsPollSet ps)
+is_woken(ErtsPollSet *ps)
 {
-#if defined(USE_THREADS) || ERTS_POLL_ASYNC_INTERRUPT_SUPPORT
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     return erts_atomic32_read_acqb(&ps->wakeup_state) != ERTS_POLL_NOT_WOKEN;
 #else
     return 0;
@@ -429,9 +375,9 @@ is_woken(ErtsPollSet ps)
 }
 
 static ERTS_INLINE int
-is_interrupted_reset(ErtsPollSet ps)
+is_interrupted_reset(ErtsPollSet *ps)
 {
-#if defined(USE_THREADS) || ERTS_POLL_ASYNC_INTERRUPT_SUPPORT
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     return (erts_atomic32_xchg_acqb(&ps->wakeup_state, ERTS_POLL_NOT_WOKEN)
 	    == ERTS_POLL_WOKEN_INTR);
 #else
@@ -440,9 +386,9 @@ is_interrupted_reset(ErtsPollSet ps)
 }
 
 static ERTS_INLINE void
-woke_up(ErtsPollSet ps)
+woke_up(ErtsPollSet *ps)
 {
-#if defined(USE_THREADS) || ERTS_POLL_ASYNC_INTERRUPT_SUPPORT
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     erts_aint32_t wakeup_state = erts_atomic32_read_acqb(&ps->wakeup_state);
     if (wakeup_state == ERTS_POLL_NOT_WOKEN)
 	(void) erts_atomic32_cmpxchg_nob(&ps->wakeup_state,
@@ -459,28 +405,23 @@ woke_up(ErtsPollSet ps)
 #if ERTS_POLL_USE_WAKEUP_PIPE
 
 static ERTS_INLINE void
-wake_poller(ErtsPollSet ps, int interrupted, int async_signal_safe)
+wake_poller(ErtsPollSet *ps, int interrupted)
 {
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     int wake;
-    if (async_signal_safe)
-	wake = 1;
-    else {
-	erts_aint32_t wakeup_state;
-	if (!interrupted)
-	    wakeup_state = erts_atomic32_cmpxchg_relb(&ps->wakeup_state,
-						      ERTS_POLL_WOKEN,
-						      ERTS_POLL_NOT_WOKEN);
-	else
-            wakeup_state = erts_atomic32_xchg_relb(&ps->wakeup_state,
-                                                   ERTS_POLL_WOKEN_INTR);
-	wake = wakeup_state == ERTS_POLL_NOT_WOKEN;
-    }
-    /*
-     * NOTE: This function might be called from signal handlers in the
-     *       non-smp case; therefore, it has to be async-signal safe in
-     *       the non-smp case.
-     */
-    if (wake) {
+    erts_aint32_t wakeup_state;
+    if (!interrupted)
+        wakeup_state = erts_atomic32_cmpxchg_relb(&ps->wakeup_state,
+                                                  ERTS_POLL_WOKEN,
+                                                  ERTS_POLL_NOT_WOKEN);
+    else
+        wakeup_state = erts_atomic32_xchg_relb(&ps->wakeup_state,
+                                               ERTS_POLL_WOKEN_INTR);
+    wake = wakeup_state == ERTS_POLL_NOT_WOKEN;
+
+    if (wake)
+#endif
+    {
 	ssize_t res;
 	if (ps->wake_fds[1] < 0)
 	    return; /* Not initialized yet */
@@ -489,36 +430,27 @@ wake_poller(ErtsPollSet ps, int interrupted, int async_signal_safe)
 	    res = write(ps->wake_fds[1], "!", 1);
 	} while (res < 0 && errno == EINTR);
 	if (res <= 0 && errno != ERRNO_BLOCK) {
-	    if (async_signal_safe)
-		fatal_error_async_signal_safe(__FILE__
-					      ":XXX:wake_poller(): "
-					      "Failed to write on wakeup pipe\n");
-	    else
-		fatal_error("%s:%d:wake_poller(): "
-			    "Failed to write to wakeup pipe fd=%d: "
-			    "%s (%d)\n",
-			    __FILE__, __LINE__,
-			    ps->wake_fds[1],
-			    erl_errno_id(errno), errno);
+            fatal_error("%s:%d:wake_poller(): "
+                        "Failed to write to wakeup pipe fd=%d: "
+                        "%s (%d)\n",
+                        __FILE__, __LINE__,
+                        ps->wake_fds[1],
+                        erl_errno_id(errno), errno);
 	}
     }
 }
 
 static ERTS_INLINE void
-cleanup_wakeup_pipe(ErtsPollSet ps)
+cleanup_wakeup_pipe(ErtsPollSet *ps)
 {
-#if ERTS_POLL_ASYNC_INTERRUPT_SUPPORT
     int intr = 0;
-#endif
     int fd = ps->wake_fds[0];
     int res;
     do {
 	char buf[32];
 	res = read(fd, buf, sizeof(buf));
-#if ERTS_POLL_ASYNC_INTERRUPT_SUPPORT
 	if (res > 0)
 	    intr = 1;
-#endif
     } while (res > 0 || (res < 0 && errno == EINTR));
     if (res < 0 && errno != ERRNO_BLOCK) {
 	fatal_error("%s:%d:cleanup_wakeup_pipe(): "
@@ -528,14 +460,14 @@ cleanup_wakeup_pipe(ErtsPollSet ps)
 		    fd,
 		    erl_errno_id(errno), errno);
     }
-#if ERTS_POLL_ASYNC_INTERRUPT_SUPPORT
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     if (intr)
 	erts_atomic32_set_nob(&ps->wakeup_state, ERTS_POLL_WOKEN_INTR);
 #endif
 }
 
 static void
-create_wakeup_pipe(ErtsPollSet ps)
+create_wakeup_pipe(ErtsPollSet *ps)
 {
     int do_wake = 0;
     int wake_fds[2];
@@ -552,20 +484,13 @@ create_wakeup_pipe(ErtsPollSet ps)
     SET_NONBLOCKING(wake_fds[0]);
     SET_NONBLOCKING(wake_fds[1]);
 
-#ifdef ERTS_POLL_DEBUG_PRINT
-    erts_printf("wakeup fds = {%d, %d}\n", wake_fds[0], wake_fds[1]);
-#endif
+    DEBUG_PRINT("wakeup fds = {%d, %d}", ps, wake_fds[0], wake_fds[1]);
 
     ERTS_POLL_EXPORT(erts_poll_control)(ps,
 					wake_fds[0],
+                                        ERTS_POLL_OP_ADD,
 					ERTS_POLL_EV_IN,
-					1, &do_wake);
-#if ERTS_POLL_USE_FALLBACK
-    /* We depend on the wakeup pipe being handled by kernel poll */
-    if (ps->fds_status[wake_fds[0]].flags & ERTS_POLL_FD_FLG_INFLBCK)
-	fatal_error("%s:%d:create_wakeup_pipe(): Internal error\n",
-		    __FILE__, __LINE__);
-#endif
+                                        &do_wake);
     if (ps->internal_fd_limit <= wake_fds[1])
 	ps->internal_fd_limit = wake_fds[1] + 1;
     if (ps->internal_fd_limit <= wake_fds[0])
@@ -574,84 +499,16 @@ create_wakeup_pipe(ErtsPollSet ps)
     ps->wake_fds[1] = wake_fds[1];
 }
 
-#endif /* ERTS_POLL_USE_WAKEUP_PIPE */
-
-/*
- * --- timer fd -----------------------------------------------------------
- */
-
-#if ERTS_POLL_USE_TIMERFD
-
-/* We use the timerfd when using epoll_wait to get high accuracy
-   timeouts, i.e. we want to sleep with < ms accuracy. */
-
-static void
-create_timerfd(ErtsPollSet ps)
-{
-    int do_wake = 0;
-    int timer_fd;
-    timer_fd = timerfd_create(CLOCK_MONOTONIC,0);
-    ERTS_POLL_EXPORT(erts_poll_control)(ps,
-					timer_fd,
-					ERTS_POLL_EV_IN,
-					1, &do_wake);
-#if ERTS_POLL_USE_FALLBACK
-    /* We depend on the wakeup pipe being handled by kernel poll */
-    if (ps->fds_status[timer_fd].flags & ERTS_POLL_FD_FLG_INFLBCK)
-	fatal_error("%s:%d:create_wakeup_pipe(): Internal error\n",
-		    __FILE__, __LINE__);
-#endif
-    if (ps->internal_fd_limit <= timer_fd)
-	ps->internal_fd_limit = timer_fd + 1;
-    ps->timer_fd = timer_fd;
-}
-
-static ERTS_INLINE void
-timerfd_set(ErtsPollSet ps, struct itimerspec *its)
-{
-#ifdef DEBUG
-    struct itimerspec old_its;
-    int res;
-    res = timerfd_settime(ps->timer_fd, 0, its, &old_its);
-    ASSERT(res == 0);
-    ASSERT(old_its.it_interval.tv_sec == 0 &&
-           old_its.it_interval.tv_nsec == 0 &&
-           old_its.it_value.tv_sec == 0 &&
-           old_its.it_value.tv_nsec == 0);
-
-#else
-    timerfd_settime(ps->timer_fd, 0, its, NULL);
 #endif
-}
-
-static ERTS_INLINE int
-timerfd_clear(ErtsPollSet ps, int res, int max_res) {
-
-    struct itimerspec its;
-    /* we always have to clear the timer */
-    its.it_interval.tv_sec = 0;
-    its.it_interval.tv_nsec = 0;
-    its.it_value.tv_sec = 0;
-    its.it_value.tv_nsec = 0;
-    timerfd_settime(ps->timer_fd, 0, &its, NULL);
-
-    /* only timeout fd triggered */
-    if (res == 1 && ps->res_events[0].data.fd == ps->timer_fd)
-        return 0;
-
-    return res;
-}
-
-#endif /* ERTS_POLL_USE_TIMERFD */
-
 
 /*
  * --- Poll set update requests ----------------------------------------------
  */
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
+
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
 
 static ERTS_INLINE void
-enqueue_update_request(ErtsPollSet ps, int fd)
+enqueue_update_request(ErtsPollSet *ps, int fd)
 {
     ErtsPollSetUpdateRequestsBlock *urqbp;
 
@@ -666,13 +523,11 @@ enqueue_update_request(ErtsPollSet ps, int fd)
     urqbp = ps->curr_upd_req_block;
 
     if (urqbp->len == ERTS_POLLSET_UPDATE_REQ_BLOCK_SIZE) {
-	ASSERT(!urqbp->next);
 	urqbp = erts_alloc(ERTS_ALC_T_POLLSET_UPDREQ,
 			   sizeof(ErtsPollSetUpdateRequestsBlock));
-	ps->curr_upd_req_block->next = urqbp;
-	ps->curr_upd_req_block = urqbp;
-	urqbp->next = NULL;
+	urqbp->next = ps->curr_upd_req_block;
 	urqbp->len = 0;
+	ps->curr_upd_req_block = urqbp;
     }
 
     ps->fds_status[fd].flags |= ERTS_POLL_FD_FLG_INURQ;
@@ -680,29 +535,29 @@ enqueue_update_request(ErtsPollSet ps, int fd)
 }
 
 static ERTS_INLINE void
-free_update_requests_block(ErtsPollSet ps,
+free_update_requests_block(ErtsPollSet *ps,
 			   ErtsPollSetUpdateRequestsBlock *urqbp)
 {
     if (urqbp != &ps->update_requests)
 	erts_free(ERTS_ALC_T_POLLSET_UPDREQ, (void *) urqbp);
     else {
-	urqbp->next = NULL;
 	urqbp->len = 0;
     }
 }
 
-#endif /* ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE */
+#endif /* !ERTS_POLL_USE_CONCURRENT_UPDATE */
 
 /*
  * --- Growing poll set structures -------------------------------------------
  */
 
-#ifndef ERTS_KERNEL_POLL_VERSION   /* only one shared implementation */
+#if !ERTS_NO_KERNEL_POLL_VERSION || !ERTS_ENABLE_KERNEL_POLL
+/* only one shared implementation */
 
 #define ERTS_FD_TABLE_MIN_LENGTH	1024
 #define ERTS_FD_TABLE_EXP_THRESHOLD	(2048*1024)
 
-int erts_poll_new_table_len (int old_len, int need_len)
+int erts_poll_new_table_len(int old_len, int need_len)
 {
     int new_len;
 
@@ -712,7 +567,7 @@ int erts_poll_new_table_len (int old_len, int need_len)
     }
     else {
         new_len = old_len;
-        do {            
+        do {
             if (new_len < ERTS_FD_TABLE_EXP_THRESHOLD)
                 new_len *= 2;
             else
@@ -725,30 +580,9 @@ int erts_poll_new_table_len (int old_len, int need_len)
 }
 #endif
 
-#if ERTS_POLL_USE_KERNEL_POLL
-static void
-grow_res_events(ErtsPollSet ps, int new_len)
-{
-    size_t new_size = sizeof(
-#if ERTS_POLL_USE_EPOLL
-	struct epoll_event
-#elif ERTS_POLL_USE_DEVPOLL
-	struct pollfd
-#elif ERTS_POLL_USE_KQUEUE
-	struct kevent
-#endif
-	) * erts_poll_new_table_len(ps->res_events_len, new_len);
-    /* We do not need to save previously stored data */
-    if (ps->res_events)
-	erts_free(ERTS_ALC_T_POLL_RES_EVS, ps->res_events);
-    ps->res_events = erts_alloc(ERTS_ALC_T_POLL_RES_EVS, new_size);
-    ps->res_events_len = new_len;
-}
-#endif /* ERTS_POLL_USE_KERNEL_POLL */
-
 #if ERTS_POLL_USE_POLL
 static void
-grow_poll_fds(ErtsPollSet ps, int min_ix)
+grow_poll_fds(ErtsPollSet *ps, int min_ix)
 {
     int i;
     int new_len = erts_poll_new_table_len(ps->poll_fds_len, min_ix + 1);
@@ -796,8 +630,9 @@ ensure_select_fds(int fd, ERTS_fd_set* in, ERTS_fd_set* out)
 #  define ensure_select_fds(fd, in, out) do {} while(0)
 #endif /* _DARWIN_UNLIMITED_SELECT */
 
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
 static void
-grow_fds_status(ErtsPollSet ps, int min_fd)
+grow_fds_status(ErtsPollSet *ps, int min_fd)
 {
     int i;
     int new_len = erts_poll_new_table_len(ps->fds_status_len, min_fd + 1);
@@ -816,430 +651,26 @@ grow_fds_status(ErtsPollSet ps, int min_fd)
 #endif
 	ps->fds_status[i].used_events = (ErtsPollEvents) 0;
 	ps->fds_status[i].events = (ErtsPollEvents) 0;
-#if ERTS_POLL_COALESCE_KP_RES
-	ps->fds_status[i].res_ev_ix = (unsigned short) ERTS_POLL_MAX_RES;
-#endif
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE || ERTS_POLL_USE_FALLBACK
 	ps->fds_status[i].flags = (unsigned short) 0;
-#endif
     }
     ps->fds_status_len = new_len;
 }
+#endif
 
 /*
  * --- Selecting fd to poll on -----------------------------------------------
  */
 
-#if ERTS_POLL_USE_FALLBACK
-static int update_fallback_pollset(ErtsPollSet ps, int fd);
-#endif
-
-static ERTS_INLINE int
-need_update(ErtsPollSet ps, int fd)
-{
-#if ERTS_POLL_USE_KERNEL_POLL
-    int reset;
-#endif
-
-    ASSERT(fd < ps->fds_status_len);
-
-#if ERTS_POLL_USE_KERNEL_POLL
-    reset = (int) (ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_RST);
-    if (reset && !ps->fds_status[fd].used_events) {
-	ps->fds_status[fd].flags &= ~ERTS_POLL_FD_FLG_RST;
-	reset = 0;
-    }
-#elif defined(ERTS_SMP)
-    ps->fds_status[fd].flags &= ~ERTS_POLL_FD_FLG_RST;
-#endif
-
-    if (ps->fds_status[fd].used_events != ps->fds_status[fd].events)
-	return 1;
-
-#if ERTS_POLL_USE_KERNEL_POLL
-    return reset;
-#else
-    return 0;
-#endif
-}
-
-#if ERTS_POLL_USE_BATCH_UPDATE_POLLSET
-
-#if ERTS_POLL_USE_KQUEUE
-#define ERTS_POLL_MIN_BATCH_BUF_SIZE 128
-#else
-#define ERTS_POLL_MIN_BATCH_BUF_SIZE 64
-#endif
-
-typedef struct {
-    int len;
-    int size;
-#if ERTS_POLL_USE_DEVPOLL
-    struct pollfd *buf;
-#elif ERTS_POLL_USE_KQUEUE
-    struct kevent *buf;
-    struct kevent *ebuf;
-#endif
-} ErtsPollBatchBuf;
-
-
-static ERTS_INLINE void
-setup_batch_buf(ErtsPollSet ps, ErtsPollBatchBuf *bbp)
-{
-    bbp->len = 0;
-#if ERTS_POLL_USE_DEVPOLL
-    bbp->size = ps->res_events_len;
-    bbp->buf = ps->res_events;
-#elif ERTS_POLL_USE_KQUEUE
-    bbp->size = ps->res_events_len/2;
-    bbp->buf = ps->res_events;
-    bbp->ebuf = bbp->buf + bbp->size;
-#endif
-}
-
-
-#if ERTS_POLL_USE_DEVPOLL
-
-static void
-write_batch_buf(ErtsPollSet ps, ErtsPollBatchBuf *bbp)
-{
-    ssize_t wres;
-    char *buf = (char *) bbp->buf;
-    size_t buf_size = sizeof(struct pollfd)*bbp->len;
-    
-    while (1) {
-	wres = write(ps->kp_fd, (void *) buf, buf_size);
-	if (wres < 0) {
-	    if (errno == EINTR)
-		continue;
-	    fatal_error("%s:%d:write_batch_buf(): "
-			"Failed to write to /dev/poll: "
-			"%s (%d)\n",
-			__FILE__, __LINE__,
-			erl_errno_id(errno), errno);
-	}
-	buf_size -= wres;
-	if (buf_size <= 0)
-	    break;
-	buf += wres;
-    }
-
-    if (buf_size < 0) {
-	fatal_error("%s:%d:write_devpoll_buf(): Internal error\n",
-		    __FILE__, __LINE__);
-    }
-    bbp->len = 0;
-}
-
-#elif ERTS_POLL_USE_KQUEUE
-
-static void
-write_batch_buf(ErtsPollSet ps, ErtsPollBatchBuf *bbp)
-{
-    int res;
-    int len = bbp->len;
-    struct kevent *buf = bbp->buf;
-    struct timespec ts = {0, 0};
-
-    do {
-	res = kevent(ps->kp_fd, buf, len, NULL, 0, &ts);
-    } while (res < 0 && errno == EINTR);
-    if (res < 0) {
-	int i;
-	struct kevent *ebuf = bbp->ebuf;
-	do {
-	    res = kevent(ps->kp_fd, buf, len, ebuf, len, &ts);
-	} while (res < 0 && errno == EINTR);
-	if (res < 0) {
-	    fatal_error("%s:%d: kevent() failed: %s (%d)\n",
-			__FILE__, __LINE__, erl_errno_id(errno), errno);
-	}
-	for (i = 0; i < res; i++) {
-	    if (ebuf[i].flags & EV_ERROR) {
-		short filter;
-		int fd = (int) ebuf[i].ident;
-
-		switch ((int) (long) ebuf[i].udata) {
-
-		    /*
-		     * Since we use a lazy update approach EV_DELETE will
-		     * frequently fail. This since kqueue automatically
-		     * removes a file descriptor that is closed from the
-		     * poll set.
-		     */
-		case ERTS_POLL_KQ_OP_DEL_R:
-		case ERTS_POLL_KQ_OP_DEL_W:
-		case ERTS_POLL_KQ_OP_HANDLED:
-		    break;
-
-		    /*
-		     * According to the kqueue man page EVFILT_READ support
-		     * does not imply EVFILT_WRITE support; therefore,
-		     * if an EV_ADD fail, we may have to remove other
-		     * events on this fd in the kqueue pollset before
-		     * adding fd to the fallback pollset.
-		     */
-		case ERTS_POLL_KQ_OP_ADD_W:
-		    if (ps->fds_status[fd].used_events & ERTS_POLL_EV_IN) {
-			filter = EVFILT_READ;
-			goto rm_add_fb;
-		    }
-		    goto add_fb;
-		case ERTS_POLL_KQ_OP_ADD_R:
-		    if (ps->fds_status[fd].used_events & ERTS_POLL_EV_OUT) {
-			filter = EVFILT_WRITE;
-			goto rm_add_fb;
-		    }
-		    goto add_fb;
-		case ERTS_POLL_KQ_OP_ADD2_W:
-		case ERTS_POLL_KQ_OP_ADD2_R: {
-		    int j;
-		    for (j = i+1; j < res; j++) {
-			if (fd == (int) ebuf[j].ident) {
-			    ebuf[j].udata = (void *) ERTS_POLL_KQ_OP_HANDLED;
-			    if (!(ebuf[j].flags & EV_ERROR)) {
-				switch ((int) (long) ebuf[j].udata) {
-				case ERTS_POLL_KQ_OP_ADD2_W:
-				    filter = EVFILT_WRITE;
-				    goto rm_add_fb;
-				case ERTS_POLL_KQ_OP_ADD2_R:
-				    filter = EVFILT_READ;
-				    goto rm_add_fb;
-				default:
-				    fatal_error("%s:%d:write_batch_buf(): "
-						"Internal error",
-						__FILE__, __LINE__);
-				    break;
-				}
-			    }
-			    goto add_fb;
-			}
-		    }
-		    /* The other add succeded... */
-		    filter = ((((int) (long) ebuf[i].udata)
-			       == ERTS_POLL_KQ_OP_ADD2_W)
-			      ? EVFILT_READ
-			      : EVFILT_WRITE);
-		rm_add_fb:
-		    { 
-			struct kevent kev;
-			struct timespec ts = {0, 0};
-			EV_SET(&kev, fd, filter, EV_DELETE, 0, 0, 0);
-			(void) kevent(ps->kp_fd, &kev, 1, NULL, 0, &ts);
-		    }
-
-		add_fb:
-		    ps->fds_status[fd].flags |= ERTS_POLL_FD_FLG_USEFLBCK;
-		    ASSERT(ps->fds_status[fd].used_events);
-		    ps->fds_status[fd].used_events = 0;
-		    erts_smp_atomic_dec_nob(&ps->no_of_user_fds);
-		    update_fallback_pollset(ps, fd);
-		    ASSERT(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK);
-		    break;
-		}
-		default:
-		    fatal_error("%s:%d:write_batch_buf(): Internal error",
-				__FILE__, __LINE__);
-		    break;
-		}
-	    }
-	}
-    }
-    bbp->len = 0;
-}
-
-#endif /* ERTS_POLL_USE_KQUEUE */
-
-static ERTS_INLINE void
-batch_update_pollset(ErtsPollSet ps, int fd, ErtsPollBatchBuf *bbp)
-{
-    int buf_len;
-#if ERTS_POLL_USE_DEVPOLL
-    short events;
-    struct pollfd *buf;
-#elif ERTS_POLL_USE_KQUEUE
-    struct kevent *buf;
-#endif
-
-#ifdef ERTS_POLL_DEBUG_PRINT
-    erts_printf("Doing lazy update on fd=%d\n", fd);
-#endif
-
-    if (!need_update(ps, fd))
-	return;
-
-    /* Make sure we have room for at least maximum no of entries
-       per fd */
-    if (bbp->size - bbp->len < 2)
-	write_batch_buf(ps, bbp);
-
-    buf_len = bbp->len;
-    buf = bbp->buf;
-
-    ASSERT(fd < ps->fds_status_len);
-
-#if ERTS_POLL_USE_DEVPOLL
-    events = ERTS_POLL_EV_E2N(ps->fds_status[fd].events);
-    if (!events) {
-	buf[buf_len].events = POLLREMOVE;
-	erts_smp_atomic_dec_nob(&ps->no_of_user_fds);
-    }
-    else if (!ps->fds_status[fd].used_events) {
-	buf[buf_len].events = events;
-	erts_smp_atomic_inc_nob(&ps->no_of_user_fds);
-    }
-    else {
-	if ((ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_RST)
-	    || (ps->fds_status[fd].used_events & ~events)) {
-	    /* Reset or removed events... */
-	    buf[buf_len].fd = fd;
-	    buf[buf_len].events = POLLREMOVE;
-	    buf[buf_len++].revents = 0;
-	}
-	buf[buf_len].events = events;
-    }
-    buf[buf_len].fd = fd;
-    buf[buf_len++].revents = 0;
-
-#elif ERTS_POLL_USE_KQUEUE
-
-    if (ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK) {
-	if (ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_USEFLBCK)
-	    update_fallback_pollset(ps, fd);
-	else { /* Remove from fallback and try kqueue */
-	    ErtsPollEvents events = ps->fds_status[fd].events;
-	    ps->fds_status[fd].events = (ErtsPollEvents) 0;
-	    update_fallback_pollset(ps, fd);
-	    ASSERT(!(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK));
-	    if (events) {
-		ps->fds_status[fd].events = events;
-		goto try_kqueue;
-	    }
-	}
-    }
-    else {
-	ErtsPollEvents events, used_events;
-	int mod_w, mod_r;
-    try_kqueue:
-	events = ERTS_POLL_EV_E2N(ps->fds_status[fd].events);
-	used_events = ERTS_POLL_EV_E2N(ps->fds_status[fd].used_events);
-	if (!(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_RST)) {
-	    if (!used_events &&
-		(events & ERTS_POLL_EV_IN) && (events & ERTS_POLL_EV_OUT))
-		goto do_add_rw;
-	    mod_r = ((events & ERTS_POLL_EV_IN)
-		     != (used_events & ERTS_POLL_EV_IN));
-	    mod_w = ((events & ERTS_POLL_EV_OUT)
-		     != (used_events & ERTS_POLL_EV_OUT));
-	    goto do_mod;
-	}
-	else { /* Reset */
-	    if ((events & ERTS_POLL_EV_IN) && (events & ERTS_POLL_EV_OUT)) {
-	    do_add_rw:
-		EV_SET(&buf[buf_len], fd, EVFILT_READ, EV_ADD,
-		       0, 0, (void *) ERTS_POLL_KQ_OP_ADD2_R);
-		buf_len++;
-		EV_SET(&buf[buf_len], fd, EVFILT_WRITE, EV_ADD,
-		       0, 0, (void *) ERTS_POLL_KQ_OP_ADD2_W);
-		buf_len++;
-
-	    }
-	    else {
-		mod_r = 1;
-		mod_w = 1;
-	    do_mod:
-		if (mod_r) {
-		    if (events & ERTS_POLL_EV_IN) {
-			EV_SET(&buf[buf_len], fd, EVFILT_READ, EV_ADD,
-			       0, 0, (void *) ERTS_POLL_KQ_OP_ADD_R);
-			buf_len++;
-		    }
-		    else if (used_events & ERTS_POLL_EV_IN) {
-			EV_SET(&buf[buf_len], fd, EVFILT_READ, EV_DELETE,
-			       0, 0, (void *) ERTS_POLL_KQ_OP_DEL_R);
-			buf_len++;
-		    }
-		}
-		if (mod_w) {
-		    if (events & ERTS_POLL_EV_OUT) {
-			EV_SET(&buf[buf_len], fd, EVFILT_WRITE, EV_ADD,
-			       0, 0, (void *) ERTS_POLL_KQ_OP_ADD_W);
-			buf_len++;
-		    }
-		    else if (used_events & ERTS_POLL_EV_OUT) {
-			EV_SET(&buf[buf_len], fd, EVFILT_WRITE, EV_DELETE,
-			       0, 0, (void *) ERTS_POLL_KQ_OP_DEL_W);
-			buf_len++;
-		    }
-		}
-	    }
-	}
-	if (used_events) {
-	    if (!events) {
-		erts_smp_atomic_dec_nob(&ps->no_of_user_fds);
-	    }
-	}
-	else {
-	    if (events)
-		erts_smp_atomic_inc_nob(&ps->no_of_user_fds);
-	}
-	ASSERT((events & ~(ERTS_POLL_EV_IN|ERTS_POLL_EV_OUT)) == 0);
-	ASSERT((used_events & ~(ERTS_POLL_EV_IN|ERTS_POLL_EV_OUT)) == 0);
-    }	    
-
-#endif
-
-    ps->fds_status[fd].flags &= ~ERTS_POLL_FD_FLG_RST;
-    ps->fds_status[fd].used_events = ps->fds_status[fd].events;
-
-    bbp->len = buf_len;
-}
-
-#else /* !ERTS_POLL_USE_BATCH_UPDATE_POLLSET */
-
 #if ERTS_POLL_USE_EPOLL
 static int
-#if ERTS_POLL_USE_CONCURRENT_UPDATE
-conc_update_pollset(ErtsPollSet ps, int fd, int *update_fallback)
-#else
-update_pollset(ErtsPollSet ps, int fd)
-#endif
+update_pollset(ErtsPollSet *ps, int fd, ErtsPollOp op, ErtsPollEvents events)
 {
     int res;
-    int op;
+    int epoll_op = EPOLL_CTL_MOD;
     struct epoll_event epe_templ;
     struct epoll_event epe;
 
-    ASSERT(fd < ps->fds_status_len);
-
-    if (!need_update(ps, fd))
-	return 0;
-
-#ifdef ERTS_POLL_DEBUG_PRINT
-    erts_printf("Doing update on fd=%d\n", fd);
-#endif
-    if (ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK) {
-#if ERTS_POLL_USE_CONCURRENT_UPDATE
-	if (!*update_fallback) {
-	    *update_fallback = 1;
-	    return 0;
-	}
-#endif
-	if (ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_USEFLBCK) {
-	    return update_fallback_pollset(ps, fd);
-	}
-	else { /* Remove from fallback and try epoll */
-	    ErtsPollEvents events = ps->fds_status[fd].events;
-	    ps->fds_status[fd].events = (ErtsPollEvents) 0;
-	    res = update_fallback_pollset(ps, fd);
-	    ASSERT(!(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK));
-	    if (!events)
-		return res;
-	    ps->fds_status[fd].events = events;
-	}
-    }
-
-    epe_templ.events = ERTS_POLL_EV_E2N(ps->fds_status[fd].events);
+    epe_templ.events = ERTS_POLL_EV_E2N(events) | EPOLLONESHOT;
     epe_templ.data.fd = fd;
 
 #ifdef VALGRIND
@@ -1247,30 +678,24 @@ update_pollset(ErtsPollSet ps, int fd)
     memset((void *) &epe.data, 0, sizeof(epoll_data_t));
 #endif
 
-    if (epe_templ.events && ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_RST) {
-	do {
-	    /* We init 'epe' every time since epoll_ctl() may modify it
-	       (not declared const and not documented as const). */
-	    epe.events = epe_templ.events;
-	    epe.data.fd = epe_templ.data.fd;
-	    res = epoll_ctl(ps->kp_fd, EPOLL_CTL_DEL, fd, &epe);
-	} while (res != 0 && errno == EINTR);
-	erts_smp_atomic_dec_nob(&ps->no_of_user_fds);
-	ps->fds_status[fd].used_events = 0;
-    }
-
-    if (!epe_templ.events) {
+    switch (op) {
+    case ERTS_POLL_OP_DEL:
 	/* A note on EPOLL_CTL_DEL: linux kernel versions before 2.6.9
 	   need a non-NULL event pointer even though it is ignored... */
-	op = EPOLL_CTL_DEL;
-	erts_smp_atomic_dec_nob(&ps->no_of_user_fds);
-    }
-    else if (!ps->fds_status[fd].used_events) {
-	op = EPOLL_CTL_ADD;
-	erts_smp_atomic_inc_nob(&ps->no_of_user_fds);
-    }
-    else {
-	op = EPOLL_CTL_MOD;
+        epoll_op = EPOLL_CTL_DEL;
+        epe_templ.events = 0;
+	erts_atomic_dec_nob(&ps->no_of_user_fds);
+        break;
+    case ERTS_POLL_OP_ADD:
+        epoll_op = EPOLL_CTL_ADD;
+	erts_atomic_inc_nob(&ps->no_of_user_fds);
+        break;
+    case ERTS_POLL_OP_MOD:
+        epoll_op = EPOLL_CTL_MOD;
+        break;
+    default:
+        ASSERT(0);
+        break;
     }
 
     do {
@@ -1278,33 +703,32 @@ update_pollset(ErtsPollSet ps, int fd)
 	   (not declared const and not documented as const). */
 	epe.events = epe_templ.events;
 	epe.data.fd = epe_templ.data.fd;
-	res = epoll_ctl(ps->kp_fd, op, fd, &epe);
+	res = epoll_ctl(ps->kp_fd, epoll_op, fd, &epe);
     } while (res != 0 && errno == EINTR);
 
-#if defined(ERTS_POLL_DEBUG_PRINT) && 1
+#if ERTS_POLL_DEBUG_PRINT
     {
 	int saved_errno = errno;
-	erts_printf("%s = epoll_ctl(%d, %s, %d, {Ox%x, %d})\n",
-		     res == 0 ? "0" : erl_errno_id(errno),
-		     ps->kp_fd,
-		     (op == EPOLL_CTL_ADD
-		      ? "EPOLL_CTL_ADD"
-		      : (op == EPOLL_CTL_MOD
-			 ? "EPOLL_CTL_MOD"
-			 : (op == EPOLL_CTL_DEL
-			    ? "EPOLL_CTL_DEL"
-			    : "UNKNOWN"))),
-		     fd,
-		     epe_templ.events,
-		     fd);
+	DEBUG_PRINT_FD("%s = epoll_ctl(%d, %s, %d, {0x%x, %d})",
+                       ps, fd,
+                       res == 0 ? "0" : erl_errno_id(errno),
+                       ps->kp_fd,
+                       (epoll_op == EPOLL_CTL_ADD
+                        ? "EPOLL_CTL_ADD"
+                        : (epoll_op == EPOLL_CTL_MOD
+                           ? "EPOLL_CTL_MOD"
+                           : (epoll_op == EPOLL_CTL_DEL
+                              ? "EPOLL_CTL_DEL"
+                              : "UNKNOWN"))),
+                       fd,
+                       epe_templ.events,
+                       fd);
 	errno = saved_errno;
     }
 #endif
-    if (res == 0)
-	ps->fds_status[fd].used_events = ps->fds_status[fd].events;
-    else {
+    if (res != 0) {
 	switch (op) {
-	case EPOLL_CTL_MOD:
+	case ERTS_POLL_OP_MOD:
 	    epe.events = 0;
 	    do {
 		/* We init 'epe' every time since epoll_ctl() may modify it
@@ -1313,29 +737,18 @@ update_pollset(ErtsPollSet ps, int fd)
 		epe.data.fd = fd;
 		res = epoll_ctl(ps->kp_fd, EPOLL_CTL_DEL, fd, &epe);
 	    } while (res != 0 && errno == EINTR);
-	    ps->fds_status[fd].used_events = 0;
 	/* Fall through ... */
-	case EPOLL_CTL_ADD: {
-	    ps->fds_status[fd].flags |= ERTS_POLL_FD_FLG_USEFLBCK;
-	    erts_smp_atomic_dec_nob(&ps->no_of_user_fds);
-#if ERTS_POLL_USE_CONCURRENT_UPDATE
-	    if (!*update_fallback) {
-		*update_fallback = 1;
-		return 0;
-	    }
-#endif
-	    ASSERT(!(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK));
-	    res = update_fallback_pollset(ps, fd);
-	    ASSERT(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK);
+	case ERTS_POLL_OP_ADD: {
+	    erts_atomic_dec_nob(&ps->no_of_user_fds);
+            res = ERTS_POLL_EV_NVAL;
 	    break;
 	}
-	case EPOLL_CTL_DEL: {
+	case ERTS_POLL_OP_DEL: {
 	    /*
 	     * Since we use a lazy update approach EPOLL_CTL_DEL will
 	     * frequently fail. This since epoll automatically removes
 	     * a filedescriptor that is closed from the poll set.
 	     */
-	    ps->fds_status[fd].used_events = 0;
 	    res = 0;
 	    break;
 	}
@@ -1344,68 +757,278 @@ update_pollset(ErtsPollSet ps, int fd)
 			__FILE__, __LINE__);
 	    break;
 	}
+    } else {
+        res = events;
     }
-    ps->fds_status[fd].flags &= ~ERTS_POLL_FD_FLG_RST;
     return res;
 }
 
-#if ERTS_POLL_USE_CONCURRENT_UPDATE
+#endif /* ERTS_POLL_USE_EPOLL */
+
+#if ERTS_POLL_USE_KQUEUE
+
+/* Some versions of the EV_SET macro used kevp multiple times,
+   so we define out own version that make sure that it is safe
+   to do kevp++ in the argument list. */
+#define ERTS_EV_SET(kevp, a, b, c, f) do {              \
+        struct kevent *kevp_ = kevp;                    \
+        EV_SET(kevp_, a, b, c, 0, 0, f);                \
+    } while(0)
+
 static int
-update_pollset(ErtsPollSet ps, int fd)
+update_pollset(ErtsPollSet *ps, int fd, ErtsPollOp op, ErtsPollEvents events)
 {
-    int update_fallback = 1;
-    return conc_update_pollset(ps, fd, &update_fallback);
-}
-#endif
-
-#endif /* ERTS_POLL_USE_EPOLL */
+    int res = 0, len = 0;
+    struct kevent evts[2];
+    struct timespec ts = {0, 0};
 
-#endif /* ERTS_POLL_USE_BATCH_UPDATE_POLLSET */
+#ifdef EV_DISPATCH
+    /* If we have EV_DISPATCH we use it. The kevent descriptions for both
+       read and write are added on OP_ADD and removed on OP_DEL. And then
+       after than only EV_ENABLE|EV_DISPATCH are used.
+
+       It could be possible to not modify the pollset when disabling and/or
+       deleting events, but that may cause the poll threads to be awoken
+       a lot more than they should so we take the cost here instead of
+       in the poll thread.
+
+       Note: We need to have EV_DISPATCH both when the event is enabled and
+       disabled, as otherwise the event may be triggered twice on each re-arm.
+       Not sure if this is intended or not (can't find anything about it in the
+       man page), but it seems to be the way it works...
+    */
+
+    if (op == ERTS_POLL_OP_DEL) {
+        erts_atomic_dec_nob(&ps->no_of_user_fds);
+        /* We could probably skip this delete, do we want to? */
+        ERTS_EV_SET(&evts[len++], fd, EVFILT_READ, EV_DELETE, (void *) 0);
+        ERTS_EV_SET(&evts[len++], fd, EVFILT_WRITE, EV_DELETE, (void *) 0);
+    } else if (op == ERTS_POLL_OP_ADD) {
+        uint32_t flags;
+        erts_atomic_inc_nob(&ps->no_of_user_fds);
+
+        flags = EV_ADD|EV_DISPATCH;
+        flags |= ((events & ERTS_POLL_EV_IN) ? 0 : EV_DISABLE);
+        ERTS_EV_SET(&evts[len++], fd, EVFILT_READ, flags, (void *) ERTS_POLL_EV_IN);
+
+        flags = EV_ADD|EV_DISPATCH;
+        flags |= ((events & ERTS_POLL_EV_OUT) ? 0 : EV_DISABLE);
+        ERTS_EV_SET(&evts[len++], fd, EVFILT_WRITE, flags, (void *) ERTS_POLL_EV_OUT);
+    } else {
+        uint32_t flags;
+        ASSERT(op == ERTS_POLL_OP_MOD);
 
-#if ERTS_POLL_USE_POLL || ERTS_POLL_USE_SELECT || ERTS_POLL_USE_FALLBACK
+        flags = EV_DISPATCH;
+        flags |= (events & ERTS_POLL_EV_IN) ? EV_ENABLE : EV_DISABLE;
+        ERTS_EV_SET(&evts[len++], fd, EVFILT_READ, flags, (void *) ERTS_POLL_EV_IN);
 
-#if ERTS_POLL_USE_FALLBACK
-static int update_fallback_pollset(ErtsPollSet ps, int fd)
+        flags = EV_DISPATCH;
+        flags |= (events & ERTS_POLL_EV_OUT) ? EV_ENABLE : EV_DISABLE;
+        ERTS_EV_SET(&evts[len++], fd, EVFILT_WRITE, flags, (void *) ERTS_POLL_EV_OUT);
+    }
 #else
-static int update_pollset(ErtsPollSet ps, int fd)
+    uint32_t flags = EV_ADD|EV_ONESHOT;
+
+    if (op == ERTS_POLL_OP_DEL) {
+        erts_atomic_dec_nob(&ps->no_of_user_fds);
+        /* We don't do anything when a delete is issued. The fds will be removed
+           when they are triggered, or when they are closed. */
+        events = 0;
+    } else if (op == ERTS_POLL_OP_ADD) {
+        erts_atomic_inc_nob(&ps->no_of_user_fds);
+    }
+
+    if (events & ERTS_POLL_EV_IN) {
+        ERTS_EV_SET(&evts[len++], fd, EVFILT_READ, flags, (void *) ERTS_POLL_EV_IN);
+    }
+    if (events & ERTS_POLL_EV_OUT) {
+        ERTS_EV_SET(&evts[len++], fd, EVFILT_WRITE, flags, (void *) ERTS_POLL_EV_OUT);
+    }
+
 #endif
-{
-#ifdef ERTS_POLL_DEBUG_PRINT
-#if ERTS_POLL_USE_FALLBACK
-    erts_printf("Doing fallback update on fd=%d\n", fd);
+    if (len)
+        do {
+            res = kevent(ps->kp_fd, evts, len, NULL, 0, &ts);
+        } while (res < 0 && errno == EINTR);
+#if ERTS_POLL_DEBUG_PRINT
+    {
+        int saved_errno = errno, i;
+        char keventb[255], *keventbp = keventb;
+        if (res < 0)
+            keventbp += sprintf(keventbp,"%s = ",erl_errno_id(saved_errno));
+        else
+            keventbp += sprintf(keventbp,"%d = ",res);
+        keventbp += sprintf(keventbp, "kevent(%d, {",ps->kp_fd);
+        for (i = 0; i < len; i++) {
+            const char *flags = "UNKNOWN";
+            if (evts[i].flags == EV_DELETE) flags = "EV_DELETE";
+            if (evts[i].flags == (EV_ADD|EV_ONESHOT)) flags = "EV_ADD|EV_ONESHOT";
+#ifdef EV_DISPATCH
+            if (evts[i].flags == (EV_ADD|EV_DISPATCH)) flags = "EV_ADD|EV_DISPATCH";
+            if (evts[i].flags == (EV_ADD|EV_DISABLE)) flags = "EV_ADD|EV_DISABLE";
+            if (evts[i].flags == (EV_ENABLE|EV_DISPATCH)) flags = "EV_ENABLE|EV_DISPATCH";
+            if (evts[i].flags == EV_DISABLE) flags = "EV_DISABLE";
+            if (evts[i].flags == (EV_DISABLE|EV_DISPATCH)) flags = "EV_DISABLE|EV_DISABLE";
+#endif
+
+            keventbp += sprintf(keventbp, "%s{%lu, %s, %s}",i > 0 ? ", " : "",
+                                evts[i].ident,
+                                (evts[i].filter == EVFILT_READ
+                                 ? "EVFILT_READ"
+                                 : (evts[i].filter == EVFILT_WRITE
+                                    ? "EVFILT_WRITE"
+                                    : "UNKNOWN")), flags);
+        }
+        keventbp += sprintf(keventbp, "}, %d)", len);
+        DEBUG_PRINT_FD("%s", ps, fd, keventb);
+        errno = saved_errno;
+    }
+#endif
+    if (res < 0) {
+        if (op != ERTS_POLL_OP_DEL) {
+#ifdef EV_RECEIPT
+            struct kevent receipt_evts[2];
+            len = 0;
+            ERTS_EV_SET(&evts[len++], fd, EVFILT_WRITE, EV_DELETE|EV_RECEIPT, (void *) 0);
+            ERTS_EV_SET(&evts[len++], fd, EVFILT_READ, EV_DELETE|EV_RECEIPT, (void *) 0);
+            do {
+                res = kevent(ps->kp_fd, evts, len, receipt_evts, 2, &ts);
+            } while (res < 0 && errno == EINTR);
 #else
-    erts_printf("Doing update on fd=%d\n", fd);
+            ERTS_EV_SET(&evts[0], fd, EVFILT_WRITE, EV_DELETE, (void *) 0);
+            do {
+                res = kevent(ps->kp_fd, evts, 1, NULL, 0, &ts);
+            } while (res < 0 && errno == EINTR);
+            ERTS_EV_SET(&evts[0], fd, EVFILT_READ, EV_DELETE, (void *) 0);
+            do {
+                res = kevent(ps->kp_fd, evts, 1, NULL, 0, &ts);
+            } while (res < 0 && errno == EINTR);
+#endif
+            if (op == ERTS_POLL_OP_ADD)
+                erts_atomic_dec_nob(&ps->no_of_user_fds);
+            events = ERTS_POLL_EV_NVAL;
+        } else
+            events = 0;
+    }
+    return events;
+}
+
+#endif /* ERTS_POLL_USE_KQUEUE */
+
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
+
+static ERTS_INLINE void
+init_batch_update(ErtsPollSet *ps, int len)
+{
+#if ERTS_POLL_USE_DEVPOLL
+    ASSERT(ps->poll_fds == NULL);
+    ps->poll_fds = erts_alloc(ERTS_ALC_T_TMP, sizeof(struct pollfd) * len);
+    ps->poll_fds_ix = 0;
 #endif
+}
+
+static ERTS_INLINE void
+write_batch_update(ErtsPollSet *ps)
+{
+#if ERTS_POLL_USE_DEVPOLL
+    ssize_t wres;
+    char *buf = (char *) ps->poll_fds;
+    size_t buf_size = sizeof(struct pollfd)*ps->poll_fds_ix;
+
+    while (1) {
+	wres = write(ps->kp_fd, (void *) buf, buf_size);
+	if (wres < 0) {
+	    if (errno == EINTR)
+		continue;
+	    fatal_error("%s:%d:write_batch_buf(): "
+			"Failed to write to /dev/poll: "
+			"%s (%d)\n",
+			__FILE__, __LINE__,
+			erl_errno_id(errno), errno);
+	}
+#if ERTS_POLL_DEBUG_PRINT
+        {
+            int saved_errno = errno, i;
+            char devpollb[2048], *devpollbp = devpollb;
+            devpollbp += sprintf(devpollbp, "%d = devpoll(%d, {", wres, ps->kp_fd);
+            for (i = 0; i < wres / sizeof(struct pollfd); i++) {
+                if (devpollbp == devpollb)
+                    devpollbp += sprintf(devpollbp, "%d = devpoll(%d, {", wres, ps->kp_fd);
+                devpollbp += sprintf(devpollbp, "%s{fd = %d, events = %s}",
+                                     i > 0 ? ", " : "",
+                                     ps->poll_fds[i].fd,
+                                     ev2str(ps->poll_fds[i].events));
+                if (devpollbp - devpollb > 512) {
+                    devpollbp += sprintf(devpollbp, "}, %d)", ps->poll_fds_ix);
+                    DEBUG_PRINT("%s", ps, devpollb);
+                    devpollbp = devpollb;
+                }
+            }
+            devpollbp += sprintf(devpollbp, "}, %d)", ps->poll_fds_ix);
+            DEBUG_PRINT("%s", ps, devpollb);
+            errno = saved_errno;
+        }
 #endif
 
-    ASSERT(fd < ps->fds_status_len);
-#if ERTS_POLL_USE_FALLBACK
-    ASSERT(ps->fds_status[fd].used_events
-	   ? (ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK)
-	   : (ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_USEFLBCK));
+	buf_size -= wres;
+	if (buf_size <= 0)
+	    break;
+	buf += wres;
+    }
+
+    if (buf_size < 0) {
+	fatal_error("%s:%d:write_devpoll_buf(): Internal error\n",
+		    __FILE__, __LINE__);
+    }
+    erts_free(ERTS_ALC_T_TMP, ps->poll_fds);
+    ps->poll_fds = NULL;
 #endif
+}
 
-    if (!need_update(ps, fd))
-	return 0;
+static ERTS_INLINE int
+need_update(ErtsPollSet *ps, int fd, int *resetp)
+{
+    int reset;
+    ASSERT(fd < ps->fds_status_len);
 
-#if ERTS_POLL_USE_FALLBACK
+    reset = (int) (ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_RST);
     ps->fds_status[fd].flags &= ~ERTS_POLL_FD_FLG_RST;
-#endif
+
+    *resetp = reset;
+
+    if (reset || ps->fds_status[fd].used_events != ps->fds_status[fd].events)
+	return 1;
+
+    return 0;
+}
+
+static int update_pollset(ErtsPollSet *ps, ErtsPollResFd pr[], int fd)
+{
+    int res = 0, reset = 0;
+    ErtsPollEvents events = ps->fds_status[fd].events;
+    ASSERT(fd < ps->fds_status_len);
+
+    if (!need_update(ps, fd, &reset))
+	return res;
 
 #if ERTS_POLL_USE_POLL	/* --- poll -------------------------------- */
-    if (!ps->fds_status[fd].events) {
+    if (!events) {
 	int pix = ps->fds_status[fd].pix;
 	int last_pix;
+
+        if (reset) {
+            /* When a fd has been reset, we tell the caller of erts_poll_wait
+               this by setting the fd as ERTS_POLL_EV_NONE */
+            ERTS_POLL_RES_SET_FD(&pr[res], fd);
+            ERTS_POLL_RES_SET_EVTS(&pr[res], ERTS_POLL_EV_NONE);
+            DEBUG_PRINT_FD("trig %s (poll)", ps, fd, ev2str(ERTS_POLL_EV_NONE));
+            res++;
+        }
+
 	if (pix < 0) {
-#if ERTS_POLL_USE_FALLBACK
-	    ASSERT(!(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK));
-#endif
-	    return -1;
+	    return res;
 	}
-#if ERTS_POLL_USE_FALLBACK
-	ASSERT(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK);
-#endif
-	erts_smp_atomic_dec_nob(&ps->no_of_user_fds);
+	erts_atomic_dec_nob(&ps->no_of_user_fds);
 	last_pix = --ps->no_poll_fds;
 	if (pix != last_pix) {
 	/* Move last pix to this pix */
@@ -1421,127 +1044,151 @@ static int update_pollset(ErtsPollSet ps, int fd)
 	/* Clear this fd status */
 	ps->fds_status[fd].pix = -1;
 	ps->fds_status[fd].used_events = (ErtsPollEvents) 0;
-#if ERTS_POLL_USE_FALLBACK
-	ps->fds_status[fd].flags &= ~ERTS_POLL_FD_FLG_INFLBCK;
-#endif
+
     }
     else {
 	int pix = ps->fds_status[fd].pix;
 	if (pix < 0) {
-#if ERTS_POLL_USE_FALLBACK
-	    ASSERT(!(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK)
-		    || fd == ps->kp_fd);
-#endif
-	    erts_smp_atomic_inc_nob(&ps->no_of_user_fds);
+	    erts_atomic_inc_nob(&ps->no_of_user_fds);
 	    ps->fds_status[fd].pix = pix = ps->no_poll_fds++;
 	    if (pix >= ps->poll_fds_len)
 		grow_poll_fds(ps, pix);
 	    ps->poll_fds[pix].fd = fd;
 	    ps->fds_status[fd].pix = pix;
-#if ERTS_POLL_USE_FALLBACK
-	    ps->fds_status[fd].flags |= ERTS_POLL_FD_FLG_INFLBCK;
-#endif
 	}
 
-#if ERTS_POLL_USE_FALLBACK
-	ASSERT(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK);
-#endif
-
 	/* Events to be used in next poll */
-	ps->poll_fds[pix].events = ev2pollev(ps->fds_status[fd].events);
+	ps->poll_fds[pix].events = ev2pollev(events);
 	if (ps->poll_fds[pix].revents) {
 	    /* Remove result events that we should not poll for anymore */
 	    ps->poll_fds[pix].revents
 		&= ev2pollev(~(~ps->fds_status[fd].used_events
-			       & ps->fds_status[fd].events));
+			       & events));
 	}
 	/* Save events to be used in next poll */
-	ps->fds_status[fd].used_events = ps->fds_status[fd].events;
+	ps->fds_status[fd].used_events = events;
     }
-    return 0;
+    return res;
 #elif ERTS_POLL_USE_SELECT	/* --- select ------------------------------ */
-    {
-	ErtsPollEvents events = ps->fds_status[fd].events;
+    if (!events) {
+
+        if (reset) {
+            /* When a fd has been reset, we tell the caller of erts_poll_wait
+               this by setting the fd as ERTS_POLL_EV_NONE */
+            ERTS_POLL_RES_SET_FD(&pr[res], fd);
+            ERTS_POLL_RES_SET_EVTS(&pr[res], ERTS_POLL_EV_NONE);
+            DEBUG_PRINT_FD("trig %s (select)", ps, fd, ev2str(ERTS_POLL_EV_NONE));
+            res++;
+        }
+
+        ERTS_FD_CLR(fd, &ps->input_fds);
+        ERTS_FD_CLR(fd, &ps->output_fds);
+
+        if (ps->fds_status[fd].used_events) {
+            erts_atomic_dec_nob(&ps->no_of_user_fds);
+            ps->fds_status[fd].used_events = (ErtsPollEvents) 0;
+        }
+
+        if (fd == ps->max_fd) {
+            int max = ps->max_fd;
+            for (max = ps->max_fd; max >= 0; max--)
+                if (ps->fds_status[max].used_events)
+                    break;
+            ps->max_fd = max;
+        }
+
+    } else {
+
 	ensure_select_fds(fd, &ps->input_fds, &ps->output_fds);
-	if ((ERTS_POLL_EV_IN & events)
-	    != (ERTS_POLL_EV_IN & ps->fds_status[fd].used_events)) {
-	    if (ERTS_POLL_EV_IN & events) {
-		ERTS_FD_SET(fd, &ps->input_fds);
-	    }
-	    else {
-		ERTS_FD_CLR(fd, &ps->input_fds);
-	    }
-	}
-	if ((ERTS_POLL_EV_OUT & events)
-	    != (ERTS_POLL_EV_OUT & ps->fds_status[fd].used_events)) {
-	    if (ERTS_POLL_EV_OUT & events) {
-		ERTS_FD_SET(fd, &ps->output_fds);
-	    }
-	    else {
-		ERTS_FD_CLR(fd, &ps->output_fds);
-	    }
-	}
 
-	if (!ps->fds_status[fd].used_events) {
-	    ASSERT(events);
-	    erts_smp_atomic_inc_nob(&ps->no_of_user_fds);
-#if ERTS_POLL_USE_FALLBACK
-	    ps->no_select_fds++;
-	    ps->fds_status[fd].flags |= ERTS_POLL_FD_FLG_INFLBCK;
-#endif
-	}
-	else if (!events) {
-	    ASSERT(ps->fds_status[fd].used_events);
-	    erts_smp_atomic_dec_nob(&ps->no_of_user_fds);
-	    ps->fds_status[fd].events = events;
-#if ERTS_POLL_USE_FALLBACK
-	    ps->no_select_fds--;
-	    ps->fds_status[fd].flags &= ~ERTS_POLL_FD_FLG_INFLBCK;
-#endif
-	}
+        if (!ps->fds_status[fd].used_events)
+            erts_atomic_inc_nob(&ps->no_of_user_fds);
+
+        if (events & ERTS_POLL_EV_IN)
+            ERTS_FD_SET(fd, &ps->input_fds);
+        else
+            ERTS_FD_CLR(fd, &ps->input_fds);
+
+        if (events & ERTS_POLL_EV_OUT)
+            ERTS_FD_SET(fd, &ps->output_fds);
+        else
+            ERTS_FD_CLR(fd, &ps->output_fds);
 
 	ps->fds_status[fd].used_events = events;
 
-	if (events && fd > ps->max_fd)
-	    ps->max_fd = fd;
-	else if (!events && fd == ps->max_fd) {
-	    int max = ps->max_fd;
-	    for (max = ps->max_fd; max >= 0; max--)
-		if (ps->fds_status[max].used_events)
-		    break;
-	    ps->max_fd = max;
-	}
+        if (fd > ps->max_fd)
+            ps->max_fd = fd;
     }
-    return 0;
-#endif
-}
 
-#endif /* ERTS_POLL_USE_POLL || ERTS_POLL_USE_SELECT || ERTS_POLL_USE_FALLBACK */
+    return res;
+#elif ERTS_POLL_USE_DEVPOLL
 
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
+    if (!events) {
 
-static void
-handle_update_requests(ErtsPollSet ps)
-{
-    ErtsPollSetUpdateRequestsBlock *urqbp = &ps->update_requests;
-#if ERTS_POLL_USE_BATCH_UPDATE_POLLSET
-    ErtsPollBatchBuf bb;
-    setup_batch_buf(ps, &bb);
+        if (reset) {
+            /* When a fd has been reset, we tell the caller of erts_poll_wait
+               this by setting the fd as ERTS_POLL_EV_NONE */
+            ERTS_POLL_RES_SET_FD(&pr[res], fd);
+            ERTS_POLL_RES_SET_EVTS(&pr[res], ERTS_POLL_EV_NONE);
+            DEBUG_PRINT_FD("trig %s (devpoll)", ps, fd, ev2str(ERTS_POLL_EV_NONE));
+            res++;
+        }
+
+        ps->poll_fds[ps->poll_fds_ix].fd = fd;
+        ps->poll_fds[ps->poll_fds_ix].revents = 0;
+        ps->poll_fds[ps->poll_fds_ix++].events = POLLREMOVE;
+
+        if (ps->fds_status[fd].used_events) {
+            erts_atomic_dec_nob(&ps->no_of_user_fds);
+            ps->fds_status[fd].used_events = 0;
+        }
+
+    } else {
+        if (!ps->fds_status[fd].used_events) {
+            erts_atomic_inc_nob(&ps->no_of_user_fds);
+        }
+        ps->poll_fds[ps->poll_fds_ix].fd = fd;
+        ps->poll_fds[ps->poll_fds_ix].revents = 0;
+        ps->poll_fds[ps->poll_fds_ix++].events = ERTS_POLL_EV_E2N(events);
+        ps->fds_status[fd].used_events = ps->fds_status[fd].events;
+    }
+
+    return res;
 #endif
+}
+
+static int
+handle_update_requests(ErtsPollSet *ps, ErtsPollResFd pr[], int no_fds)
+{
+    int res = 0;
+    ErtsPollSetUpdateRequestsBlock *urqbp = ps->curr_upd_req_block;
 
     while (urqbp) {
 	ErtsPollSetUpdateRequestsBlock *free_urqbp = urqbp;
 	int i;
 	int len = urqbp->len;
+
+        init_batch_update(ps, len);
+
 	for (i = 0; i < len; i++) {
 	    int fd = urqbp->fds[i];
 	    ASSERT(fd < ps->fds_status_len);
-	    ps->fds_status[fd].flags &= ~ERTS_POLL_FD_FLG_INURQ;
-#if ERTS_POLL_USE_BATCH_UPDATE_POLLSET
-	    batch_update_pollset(ps, fd, &bb);
-#else
-	    update_pollset(ps, fd);
-#endif
+            ASSERT(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INURQ);
+
+            /* We have run out of PollResFd slots to put results in,
+               so we yield here and return later for more. */
+            if (res == no_fds && pr != NULL) {
+                memmove(urqbp->fds, urqbp->fds+i, sizeof(int) * (len - i));
+                urqbp->len -= i;
+                ps->curr_upd_req_block = urqbp;
+                write_batch_update(ps);
+                return res;
+            }
+
+            if (ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INURQ) {
+                ps->fds_status[fd].flags &= ~ERTS_POLL_FD_FLG_INURQ;
+                res += update_pollset(ps, pr + res, fd);
+            }
 	}
 
 	free_urqbp = urqbp;
@@ -1549,12 +1196,9 @@ handle_update_requests(ErtsPollSet ps)
 
 	free_update_requests_block(ps, free_urqbp);
 
-    }
+        write_batch_update(ps);
 
-#if ERTS_POLL_USE_BATCH_UPDATE_POLLSET
-    if (bb.len)
-	write_batch_buf(ps, &bb);
-#endif
+    }
 
     ps->curr_upd_req_block = &ps->update_requests;
 
@@ -1563,17 +1207,19 @@ handle_update_requests(ErtsPollSet ps)
 #endif
 
     ERTS_POLLSET_UNSET_HAVE_UPDATE_REQUESTS(ps);
+    return res;
 }
 
-#endif /* ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE */
+#endif /* !ERTS_POLL_USE_CONCURRENT_UPDATE */
 
 static ERTS_INLINE ErtsPollEvents
-poll_control(ErtsPollSet ps, int fd, ErtsPollEvents events, int on, int *do_wake)
+poll_control(ErtsPollSet *ps, int fd, ErtsPollOp op,
+             ErtsPollEvents events, int *do_wake)
 {
     ErtsPollEvents new_events;
 
     if (fd < ps->internal_fd_limit || fd >= max_fds) {
-	if (fd < 0) {
+	if (fd < 0 || fd >= max_fds) {
 	    new_events = ERTS_POLL_EV_ERR;
 	    goto done;
 	}
@@ -1589,124 +1235,49 @@ poll_control(ErtsPollSet ps, int fd, ErtsPollEvents events, int on, int *do_wake
 	    goto done;
 	}
 #endif
-#if ERTS_POLL_USE_TIMERFD
-	if (fd == ps->timer_fd) {
-	    new_events = ERTS_POLL_EV_NVAL;
-	    goto done;
-	}
-#endif
     }
 
+#if ERTS_POLL_USE_CONCURRENT_UPDATE
+
+    new_events = update_pollset(ps, fd, op, events);
+
+#else /* !ERTS_POLL_USE_CONCURRENT_UPDATE */
     if (fd >= ps->fds_status_len)
 	grow_fds_status(ps, fd);
 
     ASSERT(fd < ps->fds_status_len);
 
-    new_events = ps->fds_status[fd].events;
-
-    if (events == 0) {
-	*do_wake = 0;
-	goto done;
-    }
-
-    if (on)
-	new_events |= events;
-    else
-	new_events &= ~events;
-
-    if (new_events == (ErtsPollEvents) 0) {
-#if ERTS_POLL_USE_KERNEL_POLL || defined(ERTS_SMP)
-	ps->fds_status[fd].flags |= ERTS_POLL_FD_FLG_RST;
-#endif
-#if ERTS_POLL_USE_FALLBACK
-	ps->fds_status[fd].flags &= ~ERTS_POLL_FD_FLG_USEFLBCK;
-#endif
-    }
-
-    ps->fds_status[fd].events = new_events;
-
-    if (new_events == ps->fds_status[fd].used_events
-#if ERTS_POLL_USE_KERNEL_POLL || defined(ERTS_SMP)
-	&& !(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_RST)
-#endif
-	) {
-	*do_wake = 0;
-	goto done;
-    }
-
-#if !ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
-    if (update_pollset(ps, fd) != 0)
-	new_events = ERTS_POLL_EV_ERR;
-#else /* ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE */
-
-#if ERTS_POLL_USE_CONCURRENT_UPDATE
-    if (ERTS_POLLSET_IS_POLLED(ps)) {
-	int update_fallback = 0;
-	conc_update_pollset(ps, fd, &update_fallback);
-	if (!update_fallback) {
-	    *do_wake = 0; /* no need to wake kernel poller */
-	    goto done;
-	}
+    if (op == ERTS_POLL_OP_DEL) {
+        ps->fds_status[fd].flags |= ERTS_POLL_FD_FLG_RST;
+        ps->fds_status[fd].events = 0;
+        *do_wake = 1;
+    } else if (op == ERTS_POLL_OP_ADD) {
+        ASSERT(ps->fds_status[fd].events == 0);
+        ps->fds_status[fd].events = events;
+        *do_wake = 1;
+    } else {
+        ASSERT(op == ERTS_POLL_OP_MOD);
+        ps->fds_status[fd].events = events;
+        *do_wake = 1;
     }
-#endif
+    new_events = ps->fds_status[fd].events;
 
     enqueue_update_request(ps, fd);
-	
-#ifdef ERTS_SMP
-    /*
-     * If new events have been added, we need to wake up the
-     * polling thread, but if events have been removed we don't.
-     */
-    if ((new_events && (ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_RST))
-	|| (~ps->fds_status[fd].used_events & new_events))
-	*do_wake = 1;
-#endif /* ERTS_SMP */
-
-#endif /* ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE */
+
+#endif /* !ERTS_POLL_USE_CONCURRENT_UPDATE */
 
  done:
-#ifdef ERTS_POLL_DEBUG_PRINT
-     erts_printf("0x%x = poll_control(ps, %d, 0x%x, %s) do_wake=%d\n",
-		 (int) new_events, fd, (int) events, (on ? "on" : "off"), *do_wake);
-#endif
+    DEBUG_PRINT_FD("%s = %s(%p, %d, %s, %s) do_wake=%d",
+                   ps, fd, ev2str(new_events), __FUNCTION__, ps,
+                   fd, op2str(op), ev2str(events), *do_wake);
     return new_events;
 }
 
-void
-ERTS_POLL_EXPORT(erts_poll_controlv)(ErtsPollSet ps,
-				     ErtsPollControlEntry pcev[],
-				     int len)
-{
-    int i;
-    int do_wake;
-    int final_do_wake = 0;
-
-    ERTS_POLLSET_LOCK(ps);
-
-    for (i = 0; i < len; i++) {
-	do_wake = 0;
-	pcev[i].events = poll_control(ps,
-				      pcev[i].fd,
-				      pcev[i].events,
-				      pcev[i].on,
-				      &do_wake);
-	final_do_wake |= do_wake;
-    }
-
-    ERTS_POLLSET_UNLOCK(ps);
-
-#ifdef ERTS_SMP
-    if (final_do_wake)
-	wake_poller(ps, 0, 0);
-#endif /* ERTS_SMP */
-
-}
-
 ErtsPollEvents
-ERTS_POLL_EXPORT(erts_poll_control)(ErtsPollSet ps,
+ERTS_POLL_EXPORT(erts_poll_control)(ErtsPollSet *ps,
 				    ErtsSysFdType fd,
+                                    ErtsPollOp op,
 				    ErtsPollEvents events,
-				    int on,
 				    int* do_wake) /* In: Wake up polling thread */
 				                  /* Out: Poller is woken */
 {
@@ -1714,15 +1285,15 @@ ERTS_POLL_EXPORT(erts_poll_control)(ErtsPollSet ps,
 
     ERTS_POLLSET_LOCK(ps);
 
-    res = poll_control(ps, fd, events, on, do_wake);
+    res = poll_control(ps, fd, op, events, do_wake);
 
     ERTS_POLLSET_UNLOCK(ps);
 
-#ifdef ERTS_SMP
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     if (*do_wake) {
-	wake_poller(ps, 0, 0);
+	wake_poller(ps, 0);
     }
-#endif /* ERTS_SMP */
+#endif
 
     return res;
 }
@@ -1734,188 +1305,64 @@ ERTS_POLL_EXPORT(erts_poll_control)(ErtsPollSet ps,
 #if ERTS_POLL_USE_KERNEL_POLL
 
 static ERTS_INLINE int
-save_kp_result(ErtsPollSet ps, ErtsPollResFd pr[], int max_res, int chk_fds_res)
+ERTS_POLL_EXPORT(save_result)(ErtsPollSet *ps, ErtsPollResFd pr[], int max_res, int chk_fds_res, int ebadf)
 {
-    int res = 0;
-    int i;
-    int n = chk_fds_res < max_res ? chk_fds_res : max_res;
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE || ERTS_POLL_DEBUG_PRINT || ERTS_POLL_USE_WAKEUP_PIPE
+    int n = chk_fds_res < max_res ? chk_fds_res : max_res, i;
+    int res = n;
 #if ERTS_POLL_USE_WAKEUP_PIPE
     int wake_fd = ps->wake_fds[0];
 #endif
-#if ERTS_POLL_USE_TIMERFD
-    int timer_fd = ps->timer_fd;
-#endif
 
     for (i = 0; i < n; i++) {
-
-#if ERTS_POLL_USE_EPOLL		/* --- epoll ------------------------------- */
-
-	if (ps->res_events[i].events) {
-	    int fd = ps->res_events[i].data.fd;
-	    int ix;
-	    ErtsPollEvents revents;
-#if ERTS_POLL_USE_WAKEUP_PIPE
-	    if (fd == wake_fd) {
-		cleanup_wakeup_pipe(ps);
-		continue;
-	    }
-#endif
-#if ERTS_POLL_USE_TIMERFD
-            if (fd == timer_fd) {
-                continue;
-            }
+        int fd = ERTS_POLL_RES_GET_FD(&pr[i]);
+#ifdef DEBUG_PRINT_MODE
+        ErtsPollEvents evts = ERTS_POLL_RES_GET_EVTS(pr+i);
 #endif
-	    ASSERT(!(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK));
-	    /* epoll_wait() can repeat the same fd in result array... */
-	    ix = (int) ps->fds_status[fd].res_ev_ix;
-	    ASSERT(ix >= 0);
-	    if (ix >= res || pr[ix].fd != fd) {
-		ix = res;
-		pr[ix].fd = fd;
-		pr[ix].events = (ErtsPollEvents) 0;
-	    }
-
-	    revents = ERTS_POLL_EV_N2E(ps->res_events[i].events);
-	    pr[ix].events |= revents;
-	    if (revents) {
-		if (res == ix) {
-		    ps->fds_status[fd].res_ev_ix = (unsigned short) ix;
-		    res++;
-		}
-	    }
-	}
-
-#elif ERTS_POLL_USE_KQUEUE	/* --- kqueue ------------------------------ */
 
-	struct kevent *ev;
-	int fd;
-	int ix;
-
-	ev = &ps->res_events[i];
-	fd = (int) ev->ident;
-	ASSERT(fd < ps->fds_status_len);
-	ASSERT(!(ps->fds_status[fd].flags & ERTS_POLL_FD_FLG_INFLBCK));
-	ix = (int) ps->fds_status[fd].res_ev_ix;
-
-	ASSERT(ix >= 0);
-	if (ix >= res || pr[ix].fd != fd) {
-	    ix = res;
-	    pr[ix].fd = (int) ev->ident;
-	    pr[ix].events = (ErtsPollEvents) 0;
-	}
-
-	if (ev->filter == EVFILT_READ) {
-#if ERTS_POLL_USE_WAKEUP_PIPE
-	    if (fd == wake_fd) {
-		cleanup_wakeup_pipe(ps);
-		continue;
-	    }
+        DEBUG_PRINT_FD("trig %s (%s)", ps, fd,
+                       ev2str(evts),
+#if ERTS_POLL_USE_KQUEUE
+                       "kqueue"
+#elif ERTS_POLL_USE_EPOLL
+                       "epoll"
+#else
+                       "/dev/poll"
 #endif
-	    pr[ix].events |= ERTS_POLL_EV_IN;
-	}
-	else if (ev->filter == EVFILT_WRITE)
-	    pr[ix].events |= ERTS_POLL_EV_OUT;
-	if (ev->flags & (EV_ERROR|EV_EOF)) {
-	    if ((ev->flags & EV_ERROR) && (((int) ev->data) == EBADF))
-		pr[ix].events |= ERTS_POLL_EV_NVAL;
-	    else
-		pr[ix].events |= ERTS_POLL_EV_ERR;
-	}
-	if (pr[ix].events) {
-	    if (res == ix) {
-		ps->fds_status[fd].res_ev_ix = (unsigned short) ix;
-		res++;
-	    }
-	}
+            );
 
-#elif ERTS_POLL_USE_DEVPOLL	/* --- devpoll ----------------------------- */
-
-	if (ps->res_events[i].revents) {
-	    int fd = ps->res_events[i].fd;
-	    ErtsPollEvents revents;
 #if ERTS_POLL_USE_WAKEUP_PIPE
-	    if (fd == wake_fd) {
-		cleanup_wakeup_pipe(ps);
-		continue;
-	    }
-#endif
-#if ERTS_POLL_USE_TIMERFD
-	    if (fd == timer_fd) {
-		continue;
-	    }
+        if (fd == wake_fd) {
+            cleanup_wakeup_pipe(ps);
+            ERTS_POLL_RES_SET_EVTS(&pr[i], ERTS_POLL_EV_NONE);
+            if (n == 1)
+                return 0;
+        }
 #endif
-	    revents = ERTS_POLL_EV_N2E(ps->res_events[i].events);
-	    pr[res].fd = fd;
-	    pr[res].events = revents;
-	    res++;
-	}
-
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
+        else {
+            /* Reset the events to emulate ONESHOT semantics */
+            ps->fds_status[fd].events = 0;
+            enqueue_update_request(ps, fd);
+        }
 #endif
-
     }
 
     return res;
-}
-
-#endif /* ERTS_POLL_USE_KERNEL_POLL */
-
-#if ERTS_POLL_USE_FALLBACK
-
-static int
-get_kp_results(ErtsPollSet ps, ErtsPollResFd pr[], int max_res)
-{
-    int res;
-#if ERTS_POLL_USE_KQUEUE
-    struct timespec ts = {0, 0};
-#endif
-
-    if (max_res > ps->res_events_len)
-	grow_res_events(ps, max_res);
-
-    do {
-#if ERTS_POLL_USE_EPOLL
-	res = epoll_wait(ps->kp_fd, ps->res_events, max_res, 0);
-#elif ERTS_POLL_USE_KQUEUE
-	res = kevent(ps->kp_fd, NULL, 0, ps->res_events, max_res, &ts);
-#endif
-    } while (res < 0 && errno == EINTR);
-
-    if (res < 0) {
-	fatal_error("%s:%d: %s() failed: %s (%d)\n",
-		    __FILE__, __LINE__,
-#if ERTS_POLL_USE_EPOLL
-		    "epoll_wait",
-#elif ERTS_POLL_USE_KQUEUE
-		    "kevent",
+#else
+    ASSERT(chk_fds_res <= max_res);
+    return chk_fds_res;
 #endif
-		    erl_errno_id(errno), errno);
-    }
-
-    return save_kp_result(ps, pr, max_res, res);
 }
 
-#endif /* ERTS_POLL_USE_FALLBACK */
-
-
+#else /* !ERTS_POLL_USE_KERNEL_POLL */
 
 static ERTS_INLINE int
-save_poll_result(ErtsPollSet ps, ErtsPollResFd pr[], int max_res,
-		 int chk_fds_res, int ebadf)
+ERTS_POLL_EXPORT(save_result)(ErtsPollSet *ps, ErtsPollResFd pr[], int max_res, int chk_fds_res, int ebadf)
 {
-#if ERTS_POLL_USE_DEVPOLL
-    return save_kp_result(ps, pr, max_res, chk_fds_res);
-#elif ERTS_POLL_USE_FALLBACK
-    if (!ps->fallback_used)
-	return save_kp_result(ps, pr, max_res, chk_fds_res);
-    else
-#endif /* ERTS_POLL_USE_FALLBACK */
-    {
-
 #if ERTS_POLL_USE_POLL	/* --- poll -------------------------------- */
 	int res = 0;
-#if ERTS_POLL_USE_WAKEUP_PIPE && !ERTS_POLL_USE_FALLBACK 
 	int wake_fd = ps->wake_fds[0];
-#endif
 	int i, first_ix, end_ix;
 
 	/*
@@ -1932,23 +1379,30 @@ save_poll_result(ErtsPollSet ps, ErtsPollResFd pr[], int max_res,
 		if (ps->poll_fds[i].revents != (short) 0) {
 		    int fd = ps->poll_fds[i].fd;
 		    ErtsPollEvents revents;
-#if ERTS_POLL_USE_FALLBACK
-		    if (fd == ps->kp_fd) {
-			res += get_kp_results(ps, &pr[res], max_res-res);
-			i++;
-			continue;
-		    }
-#elif ERTS_POLL_USE_WAKEUP_PIPE
 		    if (fd == wake_fd) {
 			cleanup_wakeup_pipe(ps);
 			i++;
 			continue;
 		    }
-#endif
 		    revents = pollev2ev(ps->poll_fds[i].revents);
-		    pr[res].fd = fd;
-		    pr[res].events = revents;
+		    ERTS_POLL_RES_SET_FD(&pr[res], fd);
+		    ERTS_POLL_RES_SET_EVTS(&pr[res], revents);
+
+                    /* If an fd returns as error, we may want to check the
+                       update_requests queue to see if it has been reset
+                       before delivering the result?!?! This should allow
+                       the user to do driver_dselect + close without waiting
+                       for stop_select... */
+
+                    DEBUG_PRINT_FD("trig %s (poll)", ps, ERTS_POLL_RES_GET_FD(&pr[res]),
+                                   ev2str(ERTS_POLL_RES_GET_EVTS(&pr[res])));
+
 		    res++;
+
+                    /* Clear the events for this fd in order to mimic
+                       how epoll ONESHOT works */
+                    ps->fds_status[fd].events = 0;
+                    enqueue_update_request(ps, fd);
 		}
 		i++;
 	    }
@@ -1964,9 +1418,7 @@ save_poll_result(ErtsPollSet ps, ErtsPollResFd pr[], int max_res,
 
 #elif ERTS_POLL_USE_SELECT	/* --- select ------------------------------ */
 	int res = 0;
-#if ERTS_POLL_USE_WAKEUP_PIPE && !ERTS_POLL_USE_FALLBACK 
 	int wake_fd = ps->wake_fds[0];
-#endif
 	int fd, first_fd, end_fd;
 
 	/*
@@ -1979,29 +1431,23 @@ save_poll_result(ErtsPollSet ps, ErtsPollResFd pr[], int max_res,
 	if (!ebadf) {
 	    while (1) {
 		while (fd < end_fd && res < max_res) {
-
-		    pr[res].events = (ErtsPollEvents) 0;
+                    ErtsPollEvents events = 0;
 		    if (ERTS_FD_ISSET(fd, &ps->res_input_fds)) {
-#if ERTS_POLL_USE_FALLBACK
-			if (fd == ps->kp_fd) {
-			    res += get_kp_results(ps, &pr[res], max_res-res);
-			    fd++;
-			    continue;
-			}
-#elif ERTS_POLL_USE_WAKEUP_PIPE
 			if (fd == wake_fd) {
 			    cleanup_wakeup_pipe(ps);
 			    fd++;
 			    continue;
 			}
-#endif
-			pr[res].events |= ERTS_POLL_EV_IN;
+			events |= ERTS_POLL_EV_IN;
 		    }
 		    if (ERTS_FD_ISSET(fd, &ps->res_output_fds))
-			pr[res].events |= ERTS_POLL_EV_OUT;
-		    if (pr[res].events) {
-			pr[res].fd = fd;
+			events |= ERTS_POLL_EV_OUT;
+		    if (events) {
+                        ERTS_POLL_RES_SET_FD(&pr[res], fd);
+                        ERTS_POLL_RES_SET_EVTS(&pr[res], events);
 			res++;
+                        ps->fds_status[fd].events = 0;
+                        enqueue_update_request(ps, fd);
 		    }
 		    fd++;
 		}
@@ -2034,7 +1480,7 @@ save_poll_result(ErtsPollSet ps, ErtsPollResFd pr[], int max_res,
 			if (ps->fds_status[fd].events & ERTS_POLL_EV_OUT) {
 			    oset = &ps->res_output_fds;
 			    ERTS_FD_ZERO(oset);
-			    ERTS_FD_SET(fd, oset);			
+			    ERTS_FD_SET(fd, oset);
 			}
 			do {
 			    /* Initiate 'tv' each time;
@@ -2043,49 +1489,31 @@ save_poll_result(ErtsPollSet ps, ErtsPollResFd pr[], int max_res,
 			    sres = ERTS_SELECT(ps->max_fd+1, iset, oset, NULL, &tv);
 			} while (sres < 0 && errno == EINTR);
 			if (sres < 0) {
-#if ERTS_POLL_USE_FALLBACK
-			    if (fd == ps->kp_fd) {
-				res += get_kp_results(ps,
-						      &pr[res],
-						      max_res-res);
-				fd++;
-				continue;
-			    }
-#elif ERTS_POLL_USE_WAKEUP_PIPE
 			    if (fd == wake_fd) {
 				cleanup_wakeup_pipe(ps);
 				fd++;
 				continue;
 			    }
-#endif
-			    pr[res].fd = fd;
-			    pr[res].events = ERTS_POLL_EV_NVAL;
+                            ERTS_POLL_RES_SET_FD(&pr[res], fd);
+                            ERTS_POLL_RES_SET_EVTS(&pr[res], ERTS_POLL_EV_NVAL);
 			    res++;
 			}
 			else if (sres > 0) {
-			    pr[res].fd = fd;
+                            ErtsPollEvents events = 0;
+                            ERTS_POLL_RES_SET_FD(&pr[res], fd);
 			    if (iset && ERTS_FD_ISSET(fd, iset)) {
-#if ERTS_POLL_USE_FALLBACK
-				if (fd == ps->kp_fd) {
-				    res += get_kp_results(ps,
-							  &pr[res],
-							  max_res-res);
-				    fd++;
-				    continue;
-				}
-#elif ERTS_POLL_USE_WAKEUP_PIPE
 				if (fd == wake_fd) {
 				    cleanup_wakeup_pipe(ps);
 				    fd++;
 				    continue;
 				}
-#endif
-				pr[res].events |= ERTS_POLL_EV_IN;
+				events |= ERTS_POLL_EV_IN;
 			    }
 			    if (oset && ERTS_FD_ISSET(fd, oset)) {
-				pr[res].events |= ERTS_POLL_EV_OUT;
+				events |= ERTS_POLL_EV_OUT;
 			    }
-			    ASSERT(pr[res].events);
+			    ASSERT(events);
+                            ERTS_POLL_RES_SET_EVTS(&pr[res], events);
 			    res++;
 			}
 		    }
@@ -2100,377 +1528,145 @@ save_poll_result(ErtsPollSet ps, ErtsPollResFd pr[], int max_res,
 	}
 	ps->next_sel_fd = fd;
 	return res;
-#endif
-    }
-}
-
-static ERTS_INLINE ErtsMonotonicTime
-get_timeout(ErtsPollSet ps,
-	    int resolution,
-	    ErtsMonotonicTime timeout_time)
-{
-    ErtsMonotonicTime timeout, save_timeout_time;
-
-    if (timeout_time == ERTS_POLL_NO_TIMEOUT) {
-	save_timeout_time = ERTS_MONOTONIC_TIME_MIN;
-	timeout = 0;
-    }
-    else {
-	ErtsMonotonicTime diff_time, current_time;
-	current_time = erts_get_monotonic_time(NULL);
-	diff_time = timeout_time - current_time;
-	if (diff_time <= 0) {
-	    save_timeout_time = ERTS_MONOTONIC_TIME_MIN;
-	    timeout = 0;
-	}
-	else {
-	    save_timeout_time = current_time;
-	    switch (resolution) {
-	    case 1000:
-		/* Round up to nearest even milli second */
-		timeout = ERTS_MONOTONIC_TO_MSEC(diff_time - 1) + 1;
-		if (timeout > (ErtsMonotonicTime) INT_MAX)
-		    timeout = (ErtsMonotonicTime) INT_MAX;
-		save_timeout_time += ERTS_MSEC_TO_MONOTONIC(timeout);
-		timeout -= ERTS_PREMATURE_TIMEOUT(timeout, 1000);
-		break;
-	    case 1000000:
-		/* Round up to nearest even micro second */
-		timeout = ERTS_MONOTONIC_TO_USEC(diff_time - 1) + 1;
-		save_timeout_time += ERTS_USEC_TO_MONOTONIC(timeout);
-		timeout -= ERTS_PREMATURE_TIMEOUT(timeout, 1000*1000);
-		break;
-	    case 1000000000:
-		/* Round up to nearest even nano second */
-		timeout = ERTS_MONOTONIC_TO_NSEC(diff_time - 1) + 1;
-		save_timeout_time += ERTS_NSEC_TO_MONOTONIC(timeout);
-		timeout -= ERTS_PREMATURE_TIMEOUT(timeout, 1000*1000*1000);
-		break;
-	    default:
-		ERTS_INTERNAL_ERROR("Invalid resolution");
-		timeout = 0;
-		save_timeout_time = 0;
-		break;
-	    }
-	}
-    }
-    set_timeout_time(ps, save_timeout_time);
-    return timeout;
-}
-
-#if ERTS_POLL_USE_SELECT
-
-static ERTS_INLINE int
-get_timeout_timeval(ErtsPollSet ps,
-		    SysTimeval *tvp,
-		    ErtsMonotonicTime timeout_time)
-{
-    ErtsMonotonicTime timeout = get_timeout(ps,
-					    1000*1000,
-					    timeout_time);
-
-    if (!timeout) {
-	tvp->tv_sec = 0;
-	tvp->tv_usec = 0;
-
-	return 0;
-    }
-    else {
-	ErtsMonotonicTime sec = timeout/(1000*1000);
-	tvp->tv_sec = sec;
-	tvp->tv_usec = timeout - sec*(1000*1000);
-
-	ASSERT(tvp->tv_sec >= 0);
-	ASSERT(tvp->tv_usec >= 0);
-	ASSERT(tvp->tv_usec < 1000*1000);
-
-	return !0;
-    }
-
-}
-
-#endif
-
-#if ERTS_POLL_USE_KQUEUE || (ERTS_POLL_USE_POLL && defined(HAVE_PPOLL)) || ERTS_POLL_USE_TIMERFD
-
-static ERTS_INLINE int
-get_timeout_timespec(ErtsPollSet ps,
-		     struct timespec *tsp,
-		     ErtsMonotonicTime timeout_time)
-{
-    ErtsMonotonicTime timeout = get_timeout(ps,
-					    1000*1000*1000,
-					    timeout_time);
-
-    if (!timeout) {
-	tsp->tv_sec = 0;
-	tsp->tv_nsec = 0;
-	return 0;
-    }
-    else {
-	ErtsMonotonicTime sec = timeout/(1000*1000*1000);
-	tsp->tv_sec = sec;
-	tsp->tv_nsec = timeout - sec*(1000*1000*1000);
-
-	ASSERT(tsp->tv_sec >= 0);
-	ASSERT(tsp->tv_nsec >= 0);
-	ASSERT(tsp->tv_nsec < 1000*1000*1000);
-
-	return !0;
-    }
+#endif /* ERTS_POLL_USE_SELECT */
 }
 
-#endif
-
-#if ERTS_POLL_USE_TIMERFD
+#endif /* !ERTS_POLL_USE_KERNEL_POLL */
 
 static ERTS_INLINE int
-get_timeout_itimerspec(ErtsPollSet ps,
-                       struct itimerspec *itsp,
-                       ErtsMonotonicTime timeout_time)
-{
-
-    itsp->it_interval.tv_sec = 0;
-    itsp->it_interval.tv_nsec = 0;
-
-    return get_timeout_timespec(ps, &itsp->it_value, timeout_time);
-}
-
-#endif
-
-static ERTS_INLINE int
-check_fd_events(ErtsPollSet ps, ErtsMonotonicTime timeout_time, int max_res)
+check_fd_events(ErtsPollSet *ps, ErtsPollResFd pr[], int do_wait, int max_res)
 {
     int res;
-    ERTS_MSACC_PUSH_STATE_M();
-    if (erts_smp_atomic_read_nob(&ps->no_of_user_fds) == 0
-	&& timeout_time == ERTS_POLL_NO_TIMEOUT) {
-	/* Nothing to poll and zero timeout; done... */
-	return 0;
-    }
-    else {
-	int timeout;
-#if ERTS_POLL_USE_FALLBACK
-	if (!(ps->fallback_used = ERTS_POLL_NEED_FALLBACK(ps))) {
-
-#if ERTS_POLL_USE_EPOLL		/* --- epoll ------------------------------- */
-	    if (max_res > ps->res_events_len)
-		grow_res_events(ps, max_res);
-#if ERTS_POLL_USE_TIMERFD
-            {
-                struct itimerspec its;
-                timeout = get_timeout_itimerspec(ps, &its, timeout_time);
-                if (timeout) {
-#ifdef ERTS_SMP
-                    erts_thr_progress_prepare_wait(NULL);
-#endif
-                    ERTS_MSACC_SET_STATE_CACHED_M(ERTS_MSACC_STATE_SLEEP);
-                    timerfd_set(ps, &its);
-                    res = epoll_wait(ps->kp_fd, ps->res_events, max_res, -1);
-                    res = timerfd_clear(ps, res, max_res);
-                } else {
-                    res = epoll_wait(ps->kp_fd, ps->res_events, max_res, 0);
-                }
-            }
-#else /* !ERTS_POLL_USE_TIMERFD */
-	    timeout = (int) get_timeout(ps, 1000, timeout_time);
-            if (timeout) {
-#ifdef ERTS_SMP
-		erts_thr_progress_prepare_wait(NULL);
-#endif
-                ERTS_MSACC_SET_STATE_CACHED_M(ERTS_MSACC_STATE_SLEEP);
-            }
-	    res = epoll_wait(ps->kp_fd, ps->res_events, max_res, timeout);
-#endif /* !ERTS_POLL_USE_TIMERFD */
-#elif ERTS_POLL_USE_KQUEUE	/* --- kqueue ------------------------------ */
-	    struct timespec ts;
-	    if (max_res > ps->res_events_len)
-		grow_res_events(ps, max_res);
-	    timeout = get_timeout_timespec(ps, &ts, timeout_time);
-            if (timeout) {
-#ifdef ERTS_SMP
-		erts_thr_progress_prepare_wait(NULL);
-#endif
-		ERTS_MSACC_SET_STATE_CACHED_M(ERTS_MSACC_STATE_SLEEP);
-            }
-	    res = kevent(ps->kp_fd, NULL, 0, ps->res_events, max_res, &ts);
-#endif				/* ----------------------------------------- */
-	}
-	else /* use fallback (i.e. poll() or select()) */
-#endif /* ERTS_POLL_USE_FALLBACK */
-	{
+    int timeout = do_wait ? -1 : 0;
+    DEBUG_PRINT_WAIT("Entering check_fd_events(), do_wait=%d", ps, do_wait);
+    {
+#if ERTS_POLL_USE_EPOLL                /* --- epoll ------------------------------- */
+        res = epoll_wait(ps->kp_fd, pr, max_res, timeout);
+
+#elif ERTS_POLL_USE_KQUEUE     /* --- kqueue ------------------------------ */
+        struct timespec ts = {0, 0};
+        struct timespec *tsp = timeout ? NULL : &ts;
+        res = kevent(ps->kp_fd, NULL, 0, pr, max_res, tsp);
+#elif ERTS_POLL_USE_DEVPOLL	/* --- devpoll ----------------------------- */
+        /*
+         * The ioctl() will fail with EINVAL on Solaris 10 if dp_nfds
+         * is set too high. dp_nfds should not be set greater than
+         * the maximum number of file descriptors in the poll set.
+         */
+        struct dvpoll poll_res;
+        int nfds = (int) erts_atomic_read_nob(&ps->no_of_user_fds) + 1 /* wakeup pipe */;
+        poll_res.dp_nfds = nfds < max_res ? nfds : max_res;
+        poll_res.dp_fds = pr;
+        poll_res.dp_timeout = timeout;
+        res = ioctl(ps->kp_fd, DP_POLL, &poll_res);
 
-#if ERTS_POLL_USE_DEVPOLL	/* --- devpoll ----------------------------- */
-	    /*
-	     * The ioctl() will fail with EINVAL on Solaris 10 if dp_nfds
-	     * is set too high. dp_nfds should not be set greater than
-	     * the maximum number of file descriptors in the poll set.
-	     */
-	    struct dvpoll poll_res;
-	    int nfds = (int) erts_smp_atomic_read_nob(&ps->no_of_user_fds);
-#if ERTS_POLL_USE_WAKEUP_PIPE
-	    nfds++; /* Wakeup pipe */
-#endif
-	    timeout = (int) get_timeout(ps, 1000, timeout_time);
-	    poll_res.dp_nfds = nfds < max_res ? nfds : max_res;
-	    if (poll_res.dp_nfds > ps->res_events_len)
-		grow_res_events(ps, poll_res.dp_nfds);
-	    poll_res.dp_fds = ps->res_events;
-	    if (timeout) {
-#ifdef ERTS_SMP
-		erts_thr_progress_prepare_wait(NULL);
-#endif
-                ERTS_MSACC_SET_STATE_CACHED_M(ERTS_MSACC_STATE_SLEEP);
-            }
-	    poll_res.dp_timeout = timeout;
-	    res = ioctl(ps->kp_fd, DP_POLL, &poll_res);
-#elif ERTS_POLL_USE_POLL && defined(HAVE_PPOLL)	/* --- ppoll ---------------- */
-            struct timespec ts;
-	    timeout = get_timeout_timespec(ps, &ts, timeout_time);
-            if (timeout) {
-#ifdef ERTS_SMP
-		erts_thr_progress_prepare_wait(NULL);
-#endif
-		ERTS_MSACC_SET_STATE_CACHED_M(ERTS_MSACC_STATE_SLEEP);
-            }
-            res = ppoll(ps->poll_fds, ps->no_poll_fds, &ts, NULL);
 #elif ERTS_POLL_USE_POLL        /* --- poll --------------------------------- */
-	    timeout = (int) get_timeout(ps, 1000, timeout_time);
 
-	    if (timeout) {
-#ifdef ERTS_SMP
-		erts_thr_progress_prepare_wait(NULL);
-#endif
-		ERTS_MSACC_SET_STATE_CACHED_M(ERTS_MSACC_STATE_SLEEP);
-            }
-	    res = poll(ps->poll_fds, ps->no_poll_fds, timeout);
+        res = poll(ps->poll_fds, ps->no_poll_fds, timeout);
+
 #elif ERTS_POLL_USE_SELECT	/* --- select ------------------------------ */
-	    SysTimeval to;
-	    timeout = get_timeout_timeval(ps, &to, timeout_time);
+        SysTimeval tv = {0, 0};
+        SysTimeval *tvp = timeout ? NULL : &tv;
 
-	    ERTS_FD_COPY(&ps->input_fds, &ps->res_input_fds);
-	    ERTS_FD_COPY(&ps->output_fds, &ps->res_output_fds);
+        ERTS_FD_COPY(&ps->input_fds, &ps->res_input_fds);
+        ERTS_FD_COPY(&ps->output_fds, &ps->res_output_fds);
 
-	    if (timeout) {
-#ifdef ERTS_SMP
-		erts_thr_progress_prepare_wait(NULL);
-#endif
-		ERTS_MSACC_SET_STATE_CACHED_M(ERTS_MSACC_STATE_SLEEP);
-	    }
-	    res = ERTS_SELECT(ps->max_fd + 1,
-			      &ps->res_input_fds,
-			      &ps->res_output_fds,
-			      NULL,
-			      &to);
-#ifdef ERTS_SMP
-	    if (timeout) {
-		erts_thr_progress_finalize_wait(NULL);
-		ERTS_MSACC_POP_STATE_M();
-	    }
-	    if (res < 0
-		&& errno == EBADF
-		&& ERTS_POLLSET_HAVE_UPDATE_REQUESTS(ps)) {
-		/*
-		 * This may have happened because another thread deselected
-		 * a fd in our poll set and then closed it, i.e. the driver
-		 * behaved correctly. We wan't to avoid looking for a bad
-		 * fd, that may even not exist anymore. Therefore, handle
-		 * update requests and try again.
-		 *
-		 * We don't know how much of the timeout is left; therfore,
-		 * we use a zero timeout. If no error occur and no events
-		 * have triggered, we fake an EAGAIN error and let the caller
-		 * restart us.
-		 */
-		to.tv_sec = 0;
-		to.tv_usec = 0;
-		ERTS_POLLSET_LOCK(ps);
-		handle_update_requests(ps);
-		ERTS_POLLSET_UNLOCK(ps);
-		res = ERTS_SELECT(ps->max_fd + 1,
-				  &ps->res_input_fds,
-				  &ps->res_output_fds,
-				  NULL,
-				  &to);
-		if (res == 0) {
-		    errno = EAGAIN;
-		    res = -1;
-		}
-	    }
-#endif /* ERTS_SMP */
-	    return res;
+        res = ERTS_SELECT(ps->max_fd + 1,
+                          &ps->res_input_fds,
+                          &ps->res_output_fds,
+                          NULL,
+                          tvp);
 #endif				/* ----------------------------------------- */
-	}
-	if (timeout) {
-#ifdef ERTS_SMP
-	    erts_thr_progress_finalize_wait(NULL);
-#endif
-	    ERTS_MSACC_POP_STATE_M();
-	}
-	return res;
     }
+    DEBUG_PRINT_WAIT("Leaving check_fd_events(), res=%d", ps, res);
+    return res;
 }
 
 int
-ERTS_POLL_EXPORT(erts_poll_wait)(ErtsPollSet ps,
+ERTS_POLL_EXPORT(erts_poll_wait)(ErtsPollSet *ps,
 				 ErtsPollResFd pr[],
-				 int *len,
-				 ErtsMonotonicTime timeout_time)
+				 int *len)
 {
-    ErtsMonotonicTime to;
-    int res, no_fds;
+    int res, no_fds, used_fds = 0;
     int ebadf = 0;
-#ifdef ERTS_SMP
+    int do_wait;
     int ps_locked = 0;
-#endif
+    ERTS_MSACC_DECLARE_CACHE();
 
     no_fds = *len;
-#ifdef ERTS_POLL_MAX_RES
-    if (no_fds >= ERTS_POLL_MAX_RES)
-	no_fds = ERTS_POLL_MAX_RES;
-#endif
-
     *len = 0;
+    ASSERT(no_fds > 0);
 
-#ifdef ERTS_POLL_DEBUG_PRINT
-    erts_printf("Entering erts_poll_wait(), timeout_time=%bps\n",
-		timeout_time);
-#endif
-
-    if (ERTS_POLLSET_SET_POLLED_CHK(ps)) {
-	res = EINVAL; /* Another thread is in erts_poll_wait()
-			 on this pollset... */
-	goto done;
-    }
-
-    to = (is_woken(ps)
-	  ? ERTS_POLL_NO_TIMEOUT /* Use zero timeout */
-	  : timeout_time);
-
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     if (ERTS_POLLSET_HAVE_UPDATE_REQUESTS(ps)) {
 	ERTS_POLLSET_LOCK(ps);
-	handle_update_requests(ps);
+	used_fds = handle_update_requests(ps, pr, no_fds);
 	ERTS_POLLSET_UNLOCK(ps);
+
+        if (used_fds == no_fds) {
+            *len = used_fds;
+            return 0;
+        }
     }
 #endif
 
+    do_wait = !is_woken(ps) && used_fds == 0;
+
+    DEBUG_PRINT_WAIT("Entering %s(), do_wait=%d", ps, __FUNCTION__, do_wait);
+
+    if (do_wait) {
+        erts_thr_progress_prepare_wait(NULL);
+        ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_SLEEP);
+    }
+
     while (1) {
-	res = check_fd_events(ps, to, no_fds);
+	res = check_fd_events(ps, pr + used_fds, do_wait, no_fds - used_fds);
+
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
+        if (res < 0
+            && errno == EBADF
+            && ERTS_POLLSET_HAVE_UPDATE_REQUESTS(ps)) {
+            /*
+             * This may have happened because another thread deselected
+             * a fd in our poll set and then closed it, i.e. the driver
+             * behaved correctly. We wan't to avoid looking for a bad
+             * fd, that may even not exist anymore. Therefore, handle
+             * update requests and try again. This behaviour should only
+             * happen when using SELECT as the polling mechanism.
+             */
+            ERTS_POLLSET_LOCK(ps);
+            used_fds += handle_update_requests(ps, pr + used_fds, no_fds - used_fds);
+            if (used_fds == no_fds) {
+                *len = used_fds;
+                ERTS_POLLSET_UNLOCK(ps);
+                return 0;
+            }
+            res = check_fd_events(ps, pr + used_fds, 0, no_fds - used_fds);
+            /* Keep the lock over the non-blocking poll in order to not
+               get any nasty races happening. */
+            ERTS_POLLSET_UNLOCK(ps);
+            if (res == 0) {
+                errno = EAGAIN;
+                res = -1;
+            }
+        }
+#endif
+
 	if (res != 0)
 	    break;
-	if (to == ERTS_POLL_NO_TIMEOUT)
-	    break;
-	if (erts_get_monotonic_time(NULL) >= timeout_time)
-	    break;
+        if (!do_wait)
+            break;
+    }
+
+    if (do_wait) {
+        erts_thr_progress_finalize_wait(NULL);
+        ERTS_MSACC_UPDATE_CACHE();
+        ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_CHECK_IO);
     }
 
     woke_up(ps);
 
-    if (res == 0) {
-	res = ETIMEDOUT;
-    }
-    else if (res < 0) {
+    if (res < 0) {
 #if ERTS_POLL_USE_SELECT
 	if (errno == EBADF) {
 	    ebadf = 1;
@@ -2484,33 +1680,24 @@ ERTS_POLL_EXPORT(erts_poll_wait)(ErtsPollSet ps,
     save_results:
 #endif
 
-#ifdef ERTS_SMP
 	ps_locked = 1;
 	ERTS_POLLSET_LOCK(ps);
-#endif
 
-	no_fds = save_poll_result(ps, pr, no_fds, res, ebadf);
+	used_fds += ERTS_POLL_EXPORT(save_result)(ps, pr + used_fds, no_fds - used_fds, res, ebadf);
 
 #ifdef HARD_DEBUG
-	check_poll_result(pr, no_fds);
+	check_poll_result(pr, used_fds);
 #endif
 
-	res = (no_fds == 0 ? (is_interrupted_reset(ps) ? EINTR : EAGAIN) : 0);
-	*len = no_fds;
+	res = (used_fds == 0 ? (is_interrupted_reset(ps) ? EINTR : EAGAIN) : 0);
+	*len = used_fds;
     }
 
-#ifdef ERTS_SMP
     if (ps_locked)
 	ERTS_POLLSET_UNLOCK(ps);
-    ERTS_POLLSET_UNSET_POLLED(ps);
-#endif
 
- done:
-    set_timeout_time(ps, ERTS_MONOTONIC_TIME_MAX);
-#ifdef ERTS_POLL_DEBUG_PRINT
-    erts_printf("Leaving %s = erts_poll_wait()\n",
-		 res == 0 ? "0" : erl_errno_id(res));
-#endif
+    DEBUG_PRINT_WAIT("Leaving %s = %s(len = %d)", ps,
+                     res == 0 ? "0" : erl_errno_id(res), __FUNCTION__, *len);
 
     return res;
 }
@@ -2520,54 +1707,13 @@ ERTS_POLL_EXPORT(erts_poll_wait)(ErtsPollSet ps,
  */
 
 void
-ERTS_POLL_EXPORT(erts_poll_interrupt)(ErtsPollSet ps, int set)
+ERTS_POLL_EXPORT(erts_poll_interrupt)(ErtsPollSet *ps, int set)
 {
-#if defined(USE_THREADS) || ERTS_POLL_ASYNC_INTERRUPT_SUPPORT
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     if (!set)
 	reset_wakeup_state(ps);
     else
-	wake_poller(ps, 1, 0);
-#endif
-}
-
-#if ERTS_POLL_ASYNC_INTERRUPT_SUPPORT
-void
-ERTS_POLL_EXPORT(erts_poll_async_sig_interrupt)(ErtsPollSet ps)
-{
-    /*
-     * NOTE: This function is called from signal handlers, it,
-     *       therefore, it has to be async-signal safe.
-     */
-    wake_poller(ps, 1, 1);
-}
-#endif
-
-/*
- * erts_poll_interrupt_timed():
- *   If 'set' != 0, interrupt thread blocked in erts_poll_wait() if it
- * is not guaranteed that it will timeout before 'msec' milli seconds.
- */
-void
-ERTS_POLL_EXPORT(erts_poll_interrupt_timed)(ErtsPollSet ps,
-					    int set,
-					    ErtsMonotonicTime timeout_time)
-{
-#if ERTS_POLL_ASYNC_INTERRUPT_SUPPORT || defined(ERTS_SMP)
-    if (!set)
-	reset_wakeup_state(ps);
-    else {
-	ErtsMonotonicTime max_wait_time = get_timeout_time(ps);
-	if (max_wait_time > timeout_time)
-	    wake_poller(ps, 1, 0);
-#ifdef ERTS_POLL_COUNT_AVOIDED_WAKEUPS
-	else {
-	    if (ERTS_POLLSET_IS_POLLED(ps))
-		erts_smp_atomic_inc_nob(&ps->no_avoided_wakeups);
-	    erts_smp_atomic_inc_nob(&ps->no_avoided_interrupts);
-	}
-	erts_smp_atomic_inc_nob(&ps->no_interrupt_timed);
-#endif
-    }
+	wake_poller(ps, 1);
 #endif
 }
 
@@ -2581,14 +1727,19 @@ ERTS_POLL_EXPORT(erts_poll_max_fds)(void)
  */
 
 void
-ERTS_POLL_EXPORT(erts_poll_init)(void)
+ERTS_POLL_EXPORT(erts_poll_init)(int *concurrent_updates)
 {
-    erts_smp_mtx_init(&pollsets_lock, "pollsets_lock", NIL,
-        ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_IO);
-    pollsets = NULL;
 
     errno = 0;
 
+    if (concurrent_updates) {
+#if ERTS_POLL_USE_CONCURRENT_UPDATE
+        *concurrent_updates = 1;
+#else
+        *concurrent_updates = 0;
+#endif
+    }
+
 #if !defined(NO_SYSCONF)
     max_fds = sysconf(_SC_OPEN_MAX);
 #elif ERTS_POLL_USE_SELECT
@@ -2607,37 +1758,28 @@ ERTS_POLL_EXPORT(erts_poll_init)(void)
 	fatal_error("erts_poll_init(): Failed to get max number of files: %s\n",
 		    erl_errno_id(errno));
 
-#ifdef ERTS_POLL_DEBUG_PRINT
     print_misc_debug_info();
-#endif
 }
 
-ErtsPollSet
-ERTS_POLL_EXPORT(erts_poll_create_pollset)(void)
+ErtsPollSet *
+ERTS_POLL_EXPORT(erts_poll_create_pollset)(int id)
 {
 #if ERTS_POLL_USE_KERNEL_POLL
     int kp_fd;
 #endif
-    ErtsPollSet ps = erts_alloc(ERTS_ALC_T_POLLSET,
-				sizeof(struct ErtsPollSet_));
+    ErtsPollSet *ps = erts_alloc(ERTS_ALC_T_POLLSET,
+				sizeof(struct ERTS_POLL_EXPORT(erts_pollset)));
+    ps->id = id;
     ps->internal_fd_limit = 0;
-    ps->fds_status = NULL;
-    ps->fds_status_len = 0;
-    erts_smp_atomic_init_nob(&ps->no_of_user_fds, 0);
+    erts_atomic_init_nob(&ps->no_of_user_fds, 0);
 #if ERTS_POLL_USE_KERNEL_POLL
     ps->kp_fd = -1;
 #if ERTS_POLL_USE_EPOLL
     kp_fd = epoll_create(256);
-    ps->res_events_len = 0;
-    ps->res_events = NULL;
 #elif ERTS_POLL_USE_DEVPOLL
     kp_fd = open("/dev/poll", O_RDWR);
-    ps->res_events_len = 0;
-    ps->res_events = NULL;
 #elif ERTS_POLL_USE_KQUEUE
     kp_fd = kqueue();
-    ps->res_events_len = 0;
-    ps->res_events = NULL;
 #endif
     if (kp_fd < 0)
 	fatal_error("erts_poll_create_pollset(): Failed to "
@@ -2651,10 +1793,6 @@ ERTS_POLL_EXPORT(erts_poll_create_pollset)(void)
 		    ": %s (%d)\n",
 		    erl_errno_id(errno), errno);
 #endif /* ERTS_POLL_USE_KERNEL_POLL */
-#if ERTS_POLL_USE_BATCH_UPDATE_POLLSET
-    /* res_events is also used as write buffer */
-    grow_res_events(ps, ERTS_POLL_MIN_BATCH_BUF_SIZE);
-#endif
 #if ERTS_POLL_USE_POLL
     ps->next_poll_fds_ix = 0;
     ps->no_poll_fds = 0;
@@ -2663,9 +1801,6 @@ ERTS_POLL_EXPORT(erts_poll_create_pollset)(void)
 #elif ERTS_POLL_USE_SELECT
     ps->next_sel_fd = 0;
     ps->max_fd = -1;
-#if ERTS_POLL_USE_FALLBACK
-    ps->no_select_fds = 0;
-#endif
 #ifdef _DARWIN_UNLIMITED_SELECT
     ps->input_fds.sz = 0;
     ps->input_fds.ptr = NULL;
@@ -2682,133 +1817,66 @@ ERTS_POLL_EXPORT(erts_poll_create_pollset)(void)
     ERTS_FD_ZERO(&ps->res_output_fds);
 #endif
 #endif
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
+    ps->fds_status = NULL;
+    ps->fds_status_len = 0;
     ps->update_requests.next = NULL;
     ps->update_requests.len = 0;
     ps->curr_upd_req_block = &ps->update_requests;
-    erts_smp_atomic32_init_nob(&ps->have_update_requests, 0);
-#endif
-#ifdef ERTS_SMP
-    erts_atomic32_init_nob(&ps->polled, 0);
-    erts_smp_mtx_init(&ps->mtx, "pollset", NIL, ERTS_LOCK_FLAGS_CATEGORY_IO);
-#endif
-#if defined(USE_THREADS) || ERTS_POLL_ASYNC_INTERRUPT_SUPPORT
-    erts_atomic32_init_nob(&ps->wakeup_state, (erts_aint32_t) 0);
-#endif
-#if ERTS_POLL_USE_WAKEUP_PIPE
-    create_wakeup_pipe(ps);
-#endif
-#if ERTS_POLL_USE_TIMERFD
-    create_timerfd(ps);
-#endif
-#if ERTS_POLL_USE_FALLBACK
-    if (kp_fd >= ps->fds_status_len)
-	grow_fds_status(ps, kp_fd);
-    /* Force kernel poll fd into fallback (poll/select) set */
-    ps->fds_status[kp_fd].flags
-	|= ERTS_POLL_FD_FLG_INFLBCK|ERTS_POLL_FD_FLG_USEFLBCK;
-    {
-	int do_wake = 0;
-	ERTS_POLL_EXPORT(erts_poll_control)(ps, kp_fd, ERTS_POLL_EV_IN, 1,
-					    &do_wake);
-    }    
+    erts_atomic32_init_nob(&ps->have_update_requests, 0);
+    erts_mtx_init(&ps->mtx, "pollset", NIL, ERTS_LOCK_FLAGS_CATEGORY_IO);
 #endif
 #if ERTS_POLL_USE_KERNEL_POLL
     if (ps->internal_fd_limit <= kp_fd)
 	ps->internal_fd_limit = kp_fd + 1;
     ps->kp_fd = kp_fd;
 #endif
-    init_timeout_time(ps);
-#ifdef ERTS_POLL_COUNT_AVOIDED_WAKEUPS
-    erts_smp_atomic_init_nob(&ps->no_avoided_wakeups, 0);
-    erts_smp_atomic_init_nob(&ps->no_avoided_interrupts, 0);
-    erts_smp_atomic_init_nob(&ps->no_interrupt_timed, 0);
-#endif
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
-    handle_update_requests(ps);
-#endif
-#if ERTS_POLL_USE_FALLBACK
-    ps->fallback_used = 0;
-#endif
-    erts_smp_atomic_set_nob(&ps->no_of_user_fds, 0); /* Don't count wakeup pipe and fallback fd */
-
-    erts_smp_mtx_lock(&pollsets_lock);
-    ps->next = pollsets;
-    pollsets = ps;
-    erts_smp_mtx_unlock(&pollsets_lock);
-
-    return ps;
-}
-
-void
-ERTS_POLL_EXPORT(erts_poll_destroy_pollset)(ErtsPollSet ps)
-{
-
-    if (ps->fds_status)
-	erts_free(ERTS_ALC_T_FD_STATUS, (void *) ps->fds_status);
-
-#if ERTS_POLL_USE_EPOLL
-    if (ps->kp_fd >= 0)
-	close(ps->kp_fd);
-    if (ps->res_events)
-	erts_free(ERTS_ALC_T_POLL_RES_EVS, (void *) ps->res_events);
-#elif ERTS_POLL_USE_DEVPOLL
-    if (ps->kp_fd >= 0)
-	close(ps->kp_fd);
-    if (ps->res_events)
-	erts_free(ERTS_ALC_T_POLL_RES_EVS, (void *) ps->res_events);
-#elif ERTS_POLL_USE_POLL
-    if (ps->poll_fds)
-	erts_free(ERTS_ALC_T_POLL_FDS, (void *) ps->poll_fds);
-#elif ERTS_POLL_USE_SELECT
-#ifdef _DARWIN_UNLIMITED_SELECT
-    if (ps->input_fds.ptr)
-	erts_free(ERTS_ALC_T_SELECT_FDS, (void *) ps->input_fds.ptr);
-    if (ps->res_input_fds.ptr)
-	erts_free(ERTS_ALC_T_SELECT_FDS, (void *) ps->res_input_fds.ptr);
-    if (ps->output_fds.ptr)
-	erts_free(ERTS_ALC_T_SELECT_FDS, (void *) ps->output_fds.ptr);
-    if (ps->res_output_fds.ptr)
-	erts_free(ERTS_ALC_T_SELECT_FDS, (void *) ps->res_output_fds.ptr);
-#endif
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
+    erts_atomic32_init_nob(&ps->wakeup_state, (erts_aint32_t) 0);
+    create_wakeup_pipe(ps);
+    handle_update_requests(ps, NULL, 0);
+    cleanup_wakeup_pipe(ps);
 #endif
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
+#if ERTS_POLL_USE_KERNEL_POLL && (defined(__DARWIN__) || defined(__APPLE__) && defined(__MACH__))
     {
-	ErtsPollSetUpdateRequestsBlock *urqbp = ps->update_requests.next;
-	while (urqbp) {
-	    ErtsPollSetUpdateRequestsBlock *free_urqbp = urqbp;
-	    urqbp = urqbp->next;
-	    free_update_requests_block(ps, free_urqbp);
-	}
-    }
-#endif
-#ifdef ERTS_SMP
-    erts_smp_mtx_destroy(&ps->mtx);
-#endif
-#if ERTS_POLL_USE_WAKEUP_PIPE
-    if (ps->wake_fds[0] >= 0)
-	close(ps->wake_fds[0]);
-    if (ps->wake_fds[1] >= 0)
-	close(ps->wake_fds[1]);
-#endif
-#if ERTS_POLL_USE_TIMERFD
-    if (ps->timer_fd >= 0)
-        close(ps->timer_fd);
-#endif
+        /*
+         * Using kqueue on OS X is a mess of brokenness...
+         *
+         * On OS X version older than 15.6 (i.e. OS X El Capitan released in July 2015),
+         * a thread waiting in kevent is not woken if an event is inserted into the kqueue
+         * by another thread and the event becomes ready. However if a new call to kevent
+         * is done by the waiting thread, the new event is found.
+         *
+         * So on effected OS X versions we could trigger the wakeup pipe so that
+         * the waiters will be woken and re-issue the kevent. However...
+         *
+         * On OS X version older then 16 (i.e. OS X Sierra released in September 2016),
+         * running the emulator driver_SUITE smp_select testcase consistently causes a
+         * kernel panic. I don't know why or what events that trigger it. But it seems
+         * like updates of the pollset while another thread is sleeping in it Creates
+         * some kind of race that triggers the kernel panic.
+         *
+         * So to deal with this, the erts configure check what OS X version is run
+         * and only enabled kernel poll on OS X 16 or newer. In addition, if someone
+         * attempts to compile Erlang on OS X 16 and then run it on OS X 15, we do the
+         * run-time check below to disallow this.
+         */
+        int major, minor, build;
+        os_version(&major,&minor,&build);
+        if (major < 16) {
+            erts_fprintf(stderr,"BROKEN KQUEUE!\n"
+                         "Erlang has been compiled with kernel-poll support,\n"
+                         "but this OS X version is known to have kernel bugs\n"
+                         "when using kernel-poll. You have two options:\n"
+                         " 1) update to a newer OS X version (OS X Sierra or newer)\n"
+                         " 2) recompile erlang without kernel-poll support\n");
+            erts_exit(1, "");
+        }
+    }
+#endif
+    erts_atomic_set_nob(&ps->no_of_user_fds, 0); /* Don't count wakeup pipe and fallback fd */
 
-    erts_smp_mtx_lock(&pollsets_lock);
-    if (ps == pollsets)
-	pollsets = pollsets->next;
-    else {
-	ErtsPollSet prev_ps;
-	for (prev_ps = pollsets; ps != prev_ps->next; prev_ps = prev_ps->next)
-            ;
-	ASSERT(ps == prev_ps->next);
-	prev_ps->next = ps->next;
-    }
-    erts_smp_mtx_unlock(&pollsets_lock);
-
-    erts_free(ERTS_ALC_T_POLLSET, (void *) ps);
+    return ps;
 }
 
 /*
@@ -2816,24 +1884,18 @@ ERTS_POLL_EXPORT(erts_poll_destroy_pollset)(ErtsPollSet ps)
  */
 
 void
-ERTS_POLL_EXPORT(erts_poll_info)(ErtsPollSet ps, ErtsPollInfo *pip)
+ERTS_POLL_EXPORT(erts_poll_info)(ErtsPollSet *ps, ErtsPollInfo *pip)
 {
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     int pending_updates;
 #endif
     Uint size = 0;
 
     ERTS_POLLSET_LOCK(ps);
 
-    size += sizeof(struct ErtsPollSet_);
+    size += sizeof(struct ERTS_POLL_EXPORT(erts_pollset));
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     size += ps->fds_status_len*sizeof(ErtsFdStatus);
-
-#if ERTS_POLL_USE_EPOLL
-    size += ps->res_events_len*sizeof(struct epoll_event);
-#elif ERTS_POLL_USE_DEVPOLL
-    size += ps->res_events_len*sizeof(struct pollfd);
-#elif ERTS_POLL_USE_KQUEUE
-    size += ps->res_events_len*sizeof(struct kevent);
 #endif
 
 #if ERTS_POLL_USE_POLL
@@ -2845,7 +1907,7 @@ ERTS_POLL_EXPORT(erts_poll_info)(ErtsPollSet ps, ErtsPollInfo *pip)
 #endif
 #endif
 
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     {
 	ErtsPollSetUpdateRequestsBlock *urqbp = ps->update_requests.next;
 	pending_updates = ps->update_requests.len;
@@ -2857,7 +1919,7 @@ ERTS_POLL_EXPORT(erts_poll_info)(ErtsPollSet ps, ErtsPollInfo *pip)
     }
 #endif
 
-    pip->primary = 
+    pip->primary =
 #if ERTS_POLL_USE_KQUEUE
 	"kqueue"
 #elif ERTS_POLL_USE_EPOLL
@@ -2871,17 +1933,7 @@ ERTS_POLL_EXPORT(erts_poll_info)(ErtsPollSet ps, ErtsPollInfo *pip)
 #endif
 	;
 
-    pip->fallback = 
-#if !ERTS_POLL_USE_FALLBACK
-	NULL
-#elif ERTS_POLL_USE_POLL
-	"poll"
-#elif ERTS_POLL_USE_SELECT
-	"select"
-#endif
-	;
-
-    pip->kernel_poll = 
+    pip->kernel_poll =
 #if !ERTS_POLL_USE_KERNEL_POLL
 	NULL
 #elif ERTS_POLL_USE_KQUEUE
@@ -2895,34 +1947,13 @@ ERTS_POLL_EXPORT(erts_poll_info)(ErtsPollSet ps, ErtsPollInfo *pip)
 
     pip->memory_size = size;
 
-    pip->poll_set_size = (int) erts_smp_atomic_read_nob(&ps->no_of_user_fds);
-#if ERTS_POLL_USE_WAKEUP_PIPE
+    pip->poll_set_size = (int) erts_atomic_read_nob(&ps->no_of_user_fds);
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     pip->poll_set_size++; /* Wakeup pipe */
 #endif
-#if ERTS_POLL_USE_TIMERFD
-    pip->poll_set_size++; /* timerfd */
-#endif
-
-    pip->fallback_poll_set_size =
-#if !ERTS_POLL_USE_FALLBACK
-	0
-#elif ERTS_POLL_USE_POLL
-	ps->no_poll_fds
-#elif ERTS_POLL_USE_SELECT
-	ps->no_select_fds
-#endif
-	;
-
-#if ERTS_POLL_USE_FALLBACK
-    /* If only kp_fd is in fallback poll set we don't use fallback... */
-    if (pip->fallback_poll_set_size == 1)
-	pip->fallback_poll_set_size = 0;
-    else
-	pip->poll_set_size++; /* kp_fd */
-#endif
 
     pip->lazy_updates =
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
 	1
 #else
 	0
@@ -2930,21 +1961,13 @@ ERTS_POLL_EXPORT(erts_poll_info)(ErtsPollSet ps, ErtsPollInfo *pip)
 	;
 
     pip->pending_updates = 
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
 	pending_updates
 #else
 	0
 #endif
 	;
 
-    pip->batch_updates = 
-#if ERTS_POLL_USE_BATCH_UPDATE_POLLSET
-	1
-#else
-	0
-#endif
-	;
-
     pip->concurrent_updates =
 #if ERTS_POLL_USE_CONCURRENT_UPDATE
 	1
@@ -2953,13 +1976,23 @@ ERTS_POLL_EXPORT(erts_poll_info)(ErtsPollSet ps, ErtsPollInfo *pip)
 #endif
 	;
 
-    pip->max_fds = max_fds;
+    pip->is_fallback =
+#if ERTS_POLL_IS_FALLBACK
+        1
+#else
+        0
+#endif
+        ;
 
-#ifdef ERTS_POLL_COUNT_AVOIDED_WAKEUPS
-    pip->no_avoided_wakeups = erts_smp_atomic_read_nob(&ps->no_avoided_wakeups);
-    pip->no_avoided_interrupts = erts_smp_atomic_read_nob(&ps->no_avoided_interrupts);
-    pip->no_interrupt_timed = erts_smp_atomic_read_nob(&ps->no_interrupt_timed);
+    pip->batch_updates =
+#if ERTS_POLL_USE_DEVPOLL
+        1
+#else
+        0
 #endif
+        ;
+
+    pip->max_fds = max_fds;
 
     ERTS_POLLSET_UNLOCK(ps);
 
@@ -2995,35 +2028,61 @@ fatal_error(char *format, ...)
     abort();
 }
 
-static void
-fatal_error_async_signal_safe(char *error_str)
+/*
+ * --- Debug -----------------------------------------------------------------
+ */
+
+#if ERTS_POLL_USE_EPOLL
+uint32_t epoll_events(int kp_fd, int fd)
 {
-    if (ERTS_SOMEONE_IS_CRASH_DUMPING || ERTS_GOT_SIGUSR1) {
-	/* See comment above in fatal_error() */
-	return;
+    /* For epoll we read the information about what is selected upon from the proc fs.*/
+    char fname[30];
+    FILE *f;
+    unsigned int pos, flags, mnt_id;
+    int line = 0;
+    sprintf(fname,"/proc/%d/fdinfo/%d",getpid(), kp_fd);
+    f = fopen(fname,"r");
+    if (!f) {
+        fprintf(stderr,"failed to open file %s, errno = %d\n", fname, errno);
+        ASSERT(0);
+        return 0;
     }
-    if (error_str) {
-	int len = 0;
-	while (error_str[len])
-	    len++;
-	if (len) {
-	    /* async signal safe */
-	    erts_silence_warn_unused_result(write(2, error_str, len));
-	}
+    if (fscanf(f,"pos:\t%x\nflags:\t%x", &pos, &flags) != 2) {
+        fprintf(stderr,"failed to parse file %s, errno = %d\n", fname, errno);
+        ASSERT(0);
+        return 0;
     }
-    abort();
+    if (fscanf(f,"\nmnt_id:\t%x\n", &mnt_id));
+    line += 3;
+    while (!feof(f)) {
+        /* tfd:       10 events: 40000019 data:       180000000a */
+        int ev_fd;
+        uint32_t events;
+        uint64_t data;
+        if (fscanf(f,"tfd:%d events:%x data:%llx\n", &ev_fd, &events,
+                   (unsigned long long*)&data) != 3) {
+            fprintf(stderr,"failed to parse file %s on line %d, errno = %d\n", fname,
+                    line,
+                    errno);
+            return 0;
+        }
+        if (fd == ev_fd) {
+            fclose(f);
+            return events;
+        }
+    }
+    fclose(f);
+    return 0;
 }
- 
-/*
- * --- Debug -----------------------------------------------------------------
- */
+#endif
 
 void
-ERTS_POLL_EXPORT(erts_poll_get_selected_events)(ErtsPollSet ps,
+ERTS_POLL_EXPORT(erts_poll_get_selected_events)(ErtsPollSet *ps,
 						ErtsPollEvents ev[],
 						int len)
 {
     int fd;
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     ERTS_POLLSET_LOCK(ps);
     for (fd = 0; fd < len; fd++) {
 	if (fd >= ps->fds_status_len)
@@ -3031,12 +2090,7 @@ ERTS_POLL_EXPORT(erts_poll_get_selected_events)(ErtsPollSet ps,
 	else {
 	    ev[fd] = ps->fds_status[fd].events;
             if (
-#if ERTS_POLL_USE_WAKEUP_PIPE
                 fd == ps->wake_fds[0] || fd == ps->wake_fds[1] ||
-#endif
-#if ERTS_POLL_USE_TIMERFD
-                fd == ps->timer_fd ||
-#endif
 #if ERTS_POLL_USE_KERNEL_POLL
                 fd == ps->kp_fd ||
 #endif
@@ -3045,7 +2099,51 @@ ERTS_POLL_EXPORT(erts_poll_get_selected_events)(ErtsPollSet ps,
 	}
     }
     ERTS_POLLSET_UNLOCK(ps);
+#elif ERTS_POLL_USE_EPOLL
 
+    /* For epoll we read the information about what is selected upon from the proc fs.*/
+    char fname[30];
+    FILE *f;
+    unsigned int pos, flags, mnt_id;
+    int line = 0;
+    sprintf(fname,"/proc/%d/fdinfo/%d",getpid(), ps->kp_fd);
+    for (fd = 0; fd < len; fd++)
+        ev[fd] = ERTS_POLL_EV_NONE;
+    f = fopen(fname,"r");
+    if (!f) {
+        fprintf(stderr,"failed to open file %s, errno = %d\n", fname, errno);
+        return;
+    }
+    if (fscanf(f,"pos:\t%x\nflags:\t%x", &pos, &flags) != 2) {
+        fprintf(stderr,"failed to parse file %s, errno = %d\n", fname, errno);
+        ASSERT(0);
+        return;
+    }
+    if (fscanf(f,"\nmnt_id:\t%x\n", &mnt_id));
+    line += 3;
+    while (!feof(f)) {
+        /* tfd:       10 events: 40000019 data:       180000000a */
+        int fd;
+        uint32_t events;
+        uint64_t data;
+        if (fscanf(f,"tfd:%d events:%x data:%llx\n", &fd, &events,
+                   (unsigned long long*)&data) != 3) {
+            fprintf(stderr,"failed to parse file %s on line %d, errno = %d\n",
+                    fname, line, errno);
+            ASSERT(0);
+            return;
+        }
+        data &= 0xFFFFFFFF;
+        ASSERT(fd == data);
+        /* Events are the events that are being monitored, which of course include
+           error and hup events, but we are only interested in IN/OUT events */
+        ev[fd] = (ERTS_POLL_EV_IN|ERTS_POLL_EV_OUT) & ERTS_POLL_EV_N2E(events);
+        line++;
+    }
+#else
+    for (fd = 0; fd < len; fd++)
+        ev[fd] = ERTS_POLL_EV_NONE;
+#endif
 }
 
 #ifdef HARD_DEBUG
@@ -3065,10 +2163,10 @@ check_poll_result(ErtsPollResFd pr[], int len)
 }
 
 
-#if ERTS_POLL_USE_DEVPOLL
+#if ERTS_POLL_USE_DEVPOLL && defined(DEBUG)
 
 static void
-check_poll_status(ErtsPollSet ps)
+check_poll_status(ErtsPollSet *ps)
 {
     int i;
     for (i = 0; i < ps->fds_status_len; i++) {
@@ -3100,34 +2198,24 @@ check_poll_status(ErtsPollSet ps)
 #endif /* ERTS_POLL_USE_DEVPOLL */
 #endif /* HARD_DEBUG */
 
-#ifdef ERTS_POLL_DEBUG_PRINT
 static void
 print_misc_debug_info(void)
 {
-    erts_printf("erts_poll using: %s lazy_updates:%s batch_updates:%s\n",
+#if ERTS_POLL_DEBUG_PRINT
+    erts_printf("erts_poll using: %s lazy_updates:%s\n",
 #if ERTS_POLL_USE_KQUEUE
 		"kqueue"
 #elif ERTS_POLL_USE_EPOLL
 		"epoll"
 #elif ERTS_POLL_USE_DEVPOLL
 		"/dev/poll"
-#endif
-#if ERTS_POLL_USE_FALLBACK
-		"-"
-#endif
-#if ERTS_POLL_USE_POLL
+#elif ERTS_POLL_USE_POLL
 		"poll"
 #elif ERTS_POLL_USE_SELECT
 		"select"
 #endif
 		,
-#if ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE
-		"true"
-#else
-		"false"
-#endif
-		,
-#if ERTS_POLL_USE_BATCH_UPDATE_POLLSET
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
 		"true"
 #else
 		"false"
@@ -3146,29 +2234,20 @@ print_misc_debug_info(void)
 #ifdef FD_SETSIZE
     erts_printf("FD_SETSIZE=%d\n", FD_SETSIZE);
 #endif
-}
-    
 #endif
+}
 
 #ifdef ERTS_ENABLE_LOCK_COUNT
-static void erts_lcnt_enable_pollset_lock_count(ErtsPollSet pollset, int enable) {
+void ERTS_POLL_EXPORT(erts_lcnt_enable_pollset_lock_count)(ErtsPollSet *pollset, int enable)
+{
+#if !ERTS_POLL_USE_CONCURRENT_UPDATE
     if(enable) {
         erts_lcnt_install_new_lock_info(&pollset->mtx.lcnt, "pollset_rm", NIL,
             ERTS_LOCK_TYPE_MUTEX | ERTS_LOCK_FLAGS_CATEGORY_IO);
     } else {
         erts_lcnt_uninstall(&pollset->mtx.lcnt);
     }
-}
-
-void ERTS_POLL_EXPORT(erts_lcnt_update_pollset_locks)(int enable) {
-    ErtsPollSet iterator;
-
-    erts_smp_mtx_lock(&pollsets_lock);
-
-    for(iterator = pollsets; iterator != NULL; iterator = iterator->next) {
-        erts_lcnt_enable_pollset_lock_count(iterator, enable);
-    }
-
-    erts_smp_mtx_unlock(&pollsets_lock);
+#endif
+    return;
 }
 #endif
diff --git a/erts/emulator/sys/common/erl_poll.h b/erts/emulator/sys/common/erl_poll.h
index b3b4d79984..e9a667cac1 100644
--- a/erts/emulator/sys/common/erl_poll.h
+++ b/erts/emulator/sys/common/erl_poll.h
@@ -18,11 +18,31 @@
  * %CopyrightEnd%
  */
 
-/*
- * Description:	Poll interface suitable for ERTS with or without
- *              SMP support.
+/**
+ * @description: Poll interface suitable for ERTS with SMP support.
+ *
+ * @author: 	Rickard Green
+ * @author: 	Lukas Larsson
+ *
+ * This header file exports macros and functions that are used to
+ * react to I/O polling events from file descriptors or wait-able
+ * objects. The API exported is the following:
  *
- * Author: 	Rickard Green
+ * defines:
+ *   ERTS_POLL_EV_NONE - No events have been set. This is not the same as 0.
+ *   ERTS_POLL_EV_IN   - Represent an IN event
+ *   ERTS_POLL_EV_OUT  - Represent an OUT event
+ *   ERTS_POLL_EV_ERR  - Represent an error event
+ *   ERTS_POLL_EV_NVAL - Represent an invalid event
+ *
+ * macro functions:
+ *   ErtsSysFdType ERTS_POLL_RES_GET_FD(ErtsPollResFd *evt);
+ *   void ERTS_POLL_RES_SET_FD(ErtsPollResFd *evt, ErtsSysFdType fd);
+ *   ErtsPollEvents ERTS_POLL_RES_GET_EVTS(ErtsPollResFd *evt)
+ *   void ERTS_POLL_RES_SET_EVTS(ErtsPollResFd *evt, ErtsPollEvents fd);
+ *
+ * functions:
+ *   See erl_poll_api.h
  */
 
 #ifndef ERL_POLL_H__
@@ -32,33 +52,27 @@
 
 #define ERTS_POLL_NO_TIMEOUT ERTS_MONOTONIC_TIME_MIN
 
-#if 0
-#define ERTS_POLL_COUNT_AVOIDED_WAKEUPS
-#endif
-
 #ifdef ERTS_ENABLE_KERNEL_POLL
-#  if defined(ERTS_KERNEL_POLL_VERSION)
-#    define ERTS_POLL_EXPORT(FUNC) FUNC ## _kp
+#  undef ERTS_ENABLE_KERNEL_POLL
+#  define ERTS_ENABLE_KERNEL_POLL 1
+#  if defined(ERTS_NO_KERNEL_POLL_VERSION)
+#    define ERTS_POLL_EXPORT(FUNC) FUNC ## _flbk
+#    undef ERTS_NO_KERNEL_POLL_VERSION
+#    define ERTS_NO_KERNEL_POLL_VERSION 1
+#    define ERTS_KERNEL_POLL_VERSION 0
 #  else
-#    define ERTS_POLL_EXPORT(FUNC) FUNC ## _nkp
-#    undef ERTS_POLL_DISABLE_KERNEL_POLL
-#    define ERTS_POLL_DISABLE_KERNEL_POLL
+#    undef ERTS_KERNEL_POLL_VERSION
+#    define ERTS_KERNEL_POLL_VERSION 1
+#    define ERTS_NO_KERNEL_POLL_VERSION 0
+#    define ERTS_POLL_EXPORT(FUNC) FUNC
 #  endif
 #else
 #    define ERTS_POLL_EXPORT(FUNC) FUNC
-#    undef ERTS_POLL_DISABLE_KERNEL_POLL
-#    define ERTS_POLL_DISABLE_KERNEL_POLL
-#endif
-
-#ifdef ERTS_POLL_DISABLE_KERNEL_POLL
-#  undef HAVE_SYS_EPOLL_H
-#  undef HAVE_SYS_EVENT_H
-#  undef HAVE_SYS_DEVPOLL_H
+#    define ERTS_ENABLE_KERNEL_POLL 0
+#    define ERTS_NO_KERNEL_POLL_VERSION 1
+#    define ERTS_KERNEL_POLL_VERSION 0
 #endif
 
-#undef ERTS_POLL_USE_KERNEL_POLL
-#define ERTS_POLL_USE_KERNEL_POLL 0
-
 #undef ERTS_POLL_USE_KQUEUE
 #define ERTS_POLL_USE_KQUEUE 0
 #undef ERTS_POLL_USE_EPOLL
@@ -70,68 +84,96 @@
 #undef ERTS_POLL_USE_SELECT
 #define ERTS_POLL_USE_SELECT 0
 
-#if defined(HAVE_SYS_EVENT_H)
-#  undef ERTS_POLL_USE_KQUEUE
-#  define ERTS_POLL_USE_KQUEUE 1
-#  undef ERTS_POLL_USE_KERNEL_POLL
-#  define ERTS_POLL_USE_KERNEL_POLL 1
-#elif defined(HAVE_SYS_EPOLL_H)
-#  undef ERTS_POLL_USE_EPOLL
-#  define ERTS_POLL_USE_EPOLL 1
-#  undef ERTS_POLL_USE_KERNEL_POLL
-#  define ERTS_POLL_USE_KERNEL_POLL 1
-#elif defined(HAVE_SYS_DEVPOLL_H)
-#  undef ERTS_POLL_USE_DEVPOLL
-#  define ERTS_POLL_USE_DEVPOLL 1
-#  undef ERTS_POLL_USE_KERNEL_POLL
-#  define ERTS_POLL_USE_KERNEL_POLL 1
+/* Defines which structure that erts_poll_wait should use to wait with
+   and how events should be represented */
+#define ERTS_POLL_USE_EPOLL_EVS 0
+#define ERTS_POLL_USE_KQUEUE_EVS 0
+#define ERTS_POLL_USE_DEVPOLL_EVS 0
+#define ERTS_POLL_USE_POLL_EVS 0
+#define ERTS_POLL_USE_SELECT_EVS 0
+
+#define ERTS_POLL_USE_KERNEL_POLL ERTS_KERNEL_POLL_VERSION
+
+#if ERTS_ENABLE_KERNEL_POLL
+#  if defined(HAVE_SYS_EVENT_H)
+#    undef ERTS_POLL_USE_KQUEUE_EVS
+#    define ERTS_POLL_USE_KQUEUE_EVS 1
+#    undef ERTS_POLL_USE_KQUEUE
+#    define ERTS_POLL_USE_KQUEUE ERTS_KERNEL_POLL_VERSION
+#  elif defined(HAVE_SYS_EPOLL_H)
+#    undef ERTS_POLL_USE_EPOLL_EVS
+#    define ERTS_POLL_USE_EPOLL_EVS 1
+#    undef ERTS_POLL_USE_EPOLL
+#    define ERTS_POLL_USE_EPOLL ERTS_KERNEL_POLL_VERSION
+#  elif defined(HAVE_SYS_DEVPOLL_H)
+#    undef ERTS_POLL_USE_DEVPOLL_EVS
+#    define ERTS_POLL_USE_DEVPOLL_EVS 1
+#    undef ERTS_POLL_USE_DEVPOLL
+#    define ERTS_POLL_USE_DEVPOLL ERTS_KERNEL_POLL_VERSION
+#  else
+#    error "Missing kernel poll implementation of erts_poll()"
+#  endif
 #endif
 
-#define ERTS_POLL_USE_FALLBACK (ERTS_POLL_USE_KQUEUE || ERTS_POLL_USE_EPOLL)
-
-#if !ERTS_POLL_USE_KERNEL_POLL || ERTS_POLL_USE_FALLBACK
+#if ERTS_NO_KERNEL_POLL_VERSION
 #  if defined(ERTS_USE_POLL)
+#    undef ERTS_POLL_USE_POLL_EVS
+#    define ERTS_POLL_USE_POLL_EVS 1
 #    undef ERTS_POLL_USE_POLL
 #    define ERTS_POLL_USE_POLL 1
 #  elif !defined(__WIN32__)
+#    undef ERTS_POLL_USE_SELECT_EVS
+#    define ERTS_POLL_USE_SELECT_EVS 1
 #    undef ERTS_POLL_USE_SELECT
 #    define ERTS_POLL_USE_SELECT 1
 #  endif
 #endif
 
-#define ERTS_POLL_USE_TIMERFD 0
+#define ERTS_POLL_USE_FALLBACK (ERTS_POLL_USE_KQUEUE || ERTS_POLL_USE_EPOLL)
 
 typedef Uint32 ErtsPollEvents;
-#undef ERTS_POLL_EV_E2N
+
+typedef enum {
+    ERTS_POLL_OP_ADD = 0,          /* Add the FD to the pollset */
+    ERTS_POLL_OP_MOD = 1,          /* Modify the FD in the pollset */
+    ERTS_POLL_OP_DEL = 2           /* Delete the FD from the pollset */
+} ErtsPollOp;
+
+#define op2str(op) (op == ERTS_POLL_OP_ADD ? "add" :            \
+                    (op == ERTS_POLL_OP_MOD ? "mod" : "del"))
 
 #if defined(__WIN32__)	/* --- win32  --------------------------------------- */
 
-#define ERTS_POLL_EV_IN   1
-#define ERTS_POLL_EV_OUT  2
-#define ERTS_POLL_EV_ERR  4
-#define ERTS_POLL_EV_NVAL 8
+#define ERTS_POLL_EV_IN    1
+#define ERTS_POLL_EV_OUT   2
+#define ERTS_POLL_EV_ERR   4
+#define ERTS_POLL_EV_NVAL  8
 
-#elif ERTS_POLL_USE_EPOLL	/* --- epoll ------------------------------- */
+#define ERTS_POLL_EV_E2N(EV) 		(EV)
+#define ERTS_POLL_EV_N2E(EV) 		(EV)
 
-#include <sys/epoll.h>
+#elif ERTS_POLL_USE_EPOLL_EVS	/* --- epoll ------------------------------- */
 
-#ifdef HAVE_SYS_TIMERFD_H
-#include <sys/timerfd.h>
-#undef ERTS_POLL_USE_TIMERFD
-#define ERTS_POLL_USE_TIMERFD 1
-#endif
+#include <sys/epoll.h>
 
 #define ERTS_POLL_EV_E2N(EV) \
   ((uint32_t) (EV))
 #define ERTS_POLL_EV_N2E(EV) \
-  ((ErtsPollEvents) (EV))
+  ((ErtsPollEvents) (EV) & ~EPOLLONESHOT)
 
 #define ERTS_POLL_EV_IN			ERTS_POLL_EV_N2E(EPOLLIN)
 #define ERTS_POLL_EV_OUT		ERTS_POLL_EV_N2E(EPOLLOUT)
 #define ERTS_POLL_EV_NVAL		ERTS_POLL_EV_N2E(EPOLLET)
 #define ERTS_POLL_EV_ERR		ERTS_POLL_EV_N2E(EPOLLERR|EPOLLHUP)
 
-#elif ERTS_POLL_USE_DEVPOLL	/* --- devpoll ----------------------------- */
+typedef struct epoll_event ErtsPollResFd;
+
+#define ERTS_POLL_RES_GET_FD(evt) ((ErtsSysFdType)((evt)->data.fd))
+#define ERTS_POLL_RES_SET_FD(evt, ident) (evt)->data.fd = ident
+#define ERTS_POLL_RES_GET_EVTS(evt) ERTS_POLL_EV_N2E((evt)->events)
+#define ERTS_POLL_RES_SET_EVTS(evt, evts) (evt)->events = ERTS_POLL_EV_E2N(evts)
+
+#elif ERTS_POLL_USE_DEVPOLL_EVS	/* --- devpoll ----------------------------- */
 
 #include <sys/devpoll.h>
 
@@ -145,12 +187,37 @@ typedef Uint32 ErtsPollEvents;
 #define ERTS_POLL_EV_NVAL		ERTS_POLL_EV_N2E(POLLNVAL)
 #define ERTS_POLL_EV_ERR		ERTS_POLL_EV_N2E(POLLERR|POLLHUP)
 
-#elif ERTS_POLL_USE_KQUEUE	/* --- kqueue ------------------------------ */
+typedef struct pollfd ErtsPollResFd;
+
+#define ERTS_POLL_RES_GET_FD(evt) ((ErtsSysFdType)((evt)->fd))
+#define ERTS_POLL_RES_SET_FD(evt, ident) (evt)->fd = ident
+#define ERTS_POLL_RES_GET_EVTS(evt) ERTS_POLL_EV_N2E((evt)->revents)
+#define ERTS_POLL_RES_SET_EVTS(evt, evts) (evt)->revents = ERTS_POLL_EV_E2N(evts)
+
+#elif ERTS_POLL_USE_KQUEUE_EVS	/* --- kqueue ------------------------------ */
 /* Kqueue use fallback defines (poll() or select()) */
+
+#include <sys/event.h>
+
+#ifdef ERTS_USE_POLL
+#  undef ERTS_POLL_USE_POLL_EVS
+#  define ERTS_POLL_USE_POLL_EVS   1
+#elif !defined(__WIN32__)
+#  undef ERTS_POLL_USE_SELECT_EVS
+#  define ERTS_POLL_USE_SELECT_EVS 1
 #endif
 
-#if ERTS_POLL_USE_POLL	/* --- poll -------------------------------- */
+typedef struct kevent ErtsPollResFd;
+
+#define ERTS_POLL_RES_GET_FD(evt) ((ErtsSysFdType)((evt)->ident))
+#define ERTS_POLL_RES_SET_FD(evt, fd) (evt)->ident = fd
+#define ERTS_POLL_RES_GET_EVTS(evt) ERTS_POLL_EV_N2E((ErtsPollEvents)(evt)->udata)
+#define ERTS_POLL_RES_SET_EVTS(evt, evts) (evt)->udata = (void*)(UWord)(ERTS_POLL_EV_E2N(evts))
+
+#endif
 
+#if ERTS_POLL_USE_POLL_EVS
+				/* --- poll -------------------------------- */
 #include <poll.h>
 
 #define ERTS_POLL_EV_NKP_E2N(EV) \
@@ -169,7 +236,7 @@ typedef Uint32 ErtsPollEvents;
 #define ERTS_POLL_EV_NKP_NVAL		ERTS_POLL_EV_N2E(POLLNVAL)
 #define ERTS_POLL_EV_NKP_ERR		ERTS_POLL_EV_N2E(POLLERR|POLLHUP)
 
-#elif ERTS_POLL_USE_SELECT	/* --- select ------------------------------ */
+#elif ERTS_POLL_USE_SELECT_EVS	/* --- select ------------------------------ */
 
 #define ERTS_POLL_EV_NKP_E2N(EV) (EV)
 #define ERTS_POLL_EV_NKP_N2E(EV) (EV)
@@ -195,73 +262,65 @@ typedef Uint32 ErtsPollEvents;
 
 #endif
 
-typedef struct ErtsPollSet_ *ErtsPollSet;
+#if !ERTS_ENABLE_KERNEL_POLL
 
-typedef struct {
-    ErtsSysFdType fd;
-    ErtsPollEvents events;
-    int on;
-} ErtsPollControlEntry;
-
-typedef struct {
+typedef struct _ErtsPollResFd {
     ErtsSysFdType fd;
     ErtsPollEvents events;
 } ErtsPollResFd;
 
+#define ERTS_POLL_RES_GET_FD(evt) (evt)->fd
+#define ERTS_POLL_RES_SET_FD(evt, ident) (evt)->fd = (ident)
+#define ERTS_POLL_RES_GET_EVTS(evt) ERTS_POLL_EV_N2E((evt)->events)
+#define ERTS_POLL_RES_SET_EVTS(evt, evts) (evt)->events = ERTS_POLL_EV_E2N(evts)
+
+#endif
+
+#define ERTS_POLL_EV_NONE (UINT_MAX & ~(ERTS_POLL_EV_IN|ERTS_POLL_EV_OUT|ERTS_POLL_EV_NVAL|ERTS_POLL_EV_ERR))
+
+#define ev2str(ev)                                                     \
+    (((ev) == 0 || (ev) == ERTS_POLL_EV_NONE) ? "NONE" :               \
+     ((ev) == ERTS_POLL_EV_IN ? "IN" :                                 \
+      ((ev) == ERTS_POLL_EV_OUT ? "OUT" :                              \
+       ((ev) == (ERTS_POLL_EV_IN|ERTS_POLL_EV_OUT) ? "IN|OUT" :        \
+        ((ev) & ERTS_POLL_EV_ERR ? "ERR" :                             \
+         ((ev) & ERTS_POLL_EV_NVAL ? "NVAL" : "OTHER"))))))
+
+
+typedef struct ERTS_POLL_EXPORT(erts_pollset) ErtsPollSet;
+
 typedef struct {
     char *primary;
-    char *fallback;
     char *kernel_poll;
     Uint memory_size;
-    int poll_set_size;
-    int fallback_poll_set_size;
+    Uint poll_set_size;
     int lazy_updates;
-    int pending_updates;
+    Uint pending_updates;
     int batch_updates;
     int concurrent_updates;
-    int max_fds;
-#ifdef ERTS_POLL_COUNT_AVOIDED_WAKEUPS
-    long no_avoided_wakeups;
-    long no_avoided_interrupts;
-    long no_interrupt_timed;
-#endif
+    int is_fallback;
+    Uint max_fds;
+    Uint active_fds;
+    Uint poll_threads;
 } ErtsPollInfo;
 
-#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
-void		ERTS_POLL_EXPORT(erts_poll_async_sig_interrupt)(ErtsPollSet);
+#if defined(ERTS_POLL_USE_FALLBACK) && ERTS_KERNEL_POLL_VERSION
+#  undef ERTS_POLL_EXPORT
+#  define ERTS_POLL_EXPORT(FUNC) FUNC ## _flbk
+#  include "erl_poll_api.h"
+#  undef ERTS_POLL_EXPORT
+#  define ERTS_POLL_EXPORT(FUNC) FUNC
+#elif !defined(ERTS_POLL_USE_FALLBACK)
+#  define ERTS_POLL_USE_FALLBACK 0
 #endif
-void		ERTS_POLL_EXPORT(erts_poll_interrupt)(ErtsPollSet,
-						      int);
-void		ERTS_POLL_EXPORT(erts_poll_interrupt_timed)(ErtsPollSet,
-							    int,
-							    ErtsMonotonicTime);
-ErtsPollEvents	ERTS_POLL_EXPORT(erts_poll_control)(ErtsPollSet,
-						    ErtsSysFdType,
-						    ErtsPollEvents,
-						    int on,
-						    int* wake_poller
-						    );
-void		ERTS_POLL_EXPORT(erts_poll_controlv)(ErtsPollSet,
-						     ErtsPollControlEntry [],
-						     int on);
-int		ERTS_POLL_EXPORT(erts_poll_wait)(ErtsPollSet,
-						 ErtsPollResFd [],
-						 int *,
-						 ErtsMonotonicTime);
-int		ERTS_POLL_EXPORT(erts_poll_max_fds)(void);
-void		ERTS_POLL_EXPORT(erts_poll_info)(ErtsPollSet,
-						 ErtsPollInfo *);
-ErtsPollSet	ERTS_POLL_EXPORT(erts_poll_create_pollset)(void);
-void		ERTS_POLL_EXPORT(erts_poll_destroy_pollset)(ErtsPollSet);
-void		ERTS_POLL_EXPORT(erts_poll_init)(void);
-void		ERTS_POLL_EXPORT(erts_poll_get_selected_events)(ErtsPollSet,
-								ErtsPollEvents [],
-								int);
 
-int erts_poll_new_table_len(int old_len, int need_len);
+#include "erl_poll_api.h"
 
-#ifdef ERTS_ENABLE_LOCK_COUNT
-void ERTS_POLL_EXPORT(erts_lcnt_update_pollset_locks)(int enable);
-#endif
+/**
+ * Get the next size of the array that holds the file descriptors.
+ * This function is used in order for the check io array and the
+ * pollset array to be of the same size.
+ */
+int erts_poll_new_table_len(int old_len, int need_len);
 
 #endif /* #ifndef ERL_POLL_H__ */
diff --git a/erts/emulator/sys/common/erl_poll_api.h b/erts/emulator/sys/common/erl_poll_api.h
new file mode 100644
index 0000000000..04beb37d1c
--- /dev/null
+++ b/erts/emulator/sys/common/erl_poll_api.h
@@ -0,0 +1,122 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 2006-2016. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+/**
+ * @description: Poll interface functions
+ * @author Lukas Larsson
+ *
+ * The functions in the header are used to interact with the poll
+ * implementation. Iff the kernel-poll implementation needs a fallback
+ * pollset, then all functions are exported twice. Once with a _flbk
+ * suffix and once without any suffix. If no fallback is needed, then
+ * only the non-suffix version is exported.
+ */
+
+/**
+ * Initialize the poll implementation. Has to be called before any other function.
+ * @param[out] concurrent_waiters if not NULL, set to 1 if more then one thread
+ * is allowed to wait in the pollsets at the same time.
+ */
+void ERTS_POLL_EXPORT(erts_poll_init)(int *concurrent_waiters);
+/**
+ * @brief Create a new pollset.
+ * @param id The unique debug id of this pollset.
+ */
+ErtsPollSet *ERTS_POLL_EXPORT(erts_poll_create_pollset)(int id);
+
+/**
+ * Modify the contents of a pollset. This function can be called while one
+ * (or possibly more) thread is waiting in the pollset.
+ *
+ * @param ps the pollset to modify
+ * @param fd the file descriptor to modify
+ * @param op the type of operation to do. Normal usage is ADD,MOD...MOD,DEL.
+ * @param evts the events that we are changing interest to. Ignored if op is DEL.
+ * @param[in] wake_poller if set to 1 any thread waiting in the pollset will be woken.
+ *   This parameter is ignored if the pollset supports concurrent waiters.
+ * @param[out] wake_poller set to 1 if the waiting thread was woken.
+ * @return The events set, or ERTS_POLL_EV_NVAL if it was not possible to add the
+ * fd to the pollset.
+ */
+ErtsPollEvents ERTS_POLL_EXPORT(erts_poll_control)(ErtsPollSet *ps,
+                                                   ErtsSysFdType fd,
+                                                   ErtsPollOp op,
+                                                   ErtsPollEvents evts,
+                                                   int *wake_poller);
+
+/**
+ * Wait for events to be ready in the pollset. If the erts_poll_init call
+ * set concurrent_waiters to 1, then multiple threads are allowed to call
+ * this function at the same time.
+ *
+ * When an event has been triggered on a fd, that event is disabled. To
+ * re-enable it the implementation has to call erts_poll_control again.
+ *
+ * @param ps the pollset to wait for events in
+ * @param res an array of fd results that the ready fds are put in.
+ * @param[in] length the length of the res array
+ * @param[out] length the number of ready events returned in res
+ * @return 0 on success, else the ERRNO of the error that happened.
+ */
+int ERTS_POLL_EXPORT(erts_poll_wait)(ErtsPollSet *ps,
+                                     ErtsPollResFd res[],
+                                     int *length);
+/**
+ * Interrupt the thread waiting in the pollset. This function should be called
+ * with set = 0 before any thread calls erts_poll_wait in order to clear any
+ * interrupts that have happened while the thread was awake.
+ *
+ * This function has no effect on pollsets that support concurrent waiters.
+ *
+ * @param ps the pollset to wake
+ * @param set if 1, interrupt the pollset, if 0 clear the interrupt flag.
+ */
+void ERTS_POLL_EXPORT(erts_poll_interrupt)(ErtsPollSet *ps, int set);
+
+/* Debug functions */
+
+/**
+ * Get the maximum number of fds supported by the pollset
+ */
+int ERTS_POLL_EXPORT(erts_poll_max_fds)(void);
+/**
+ * Get information about the given pollset
+ */
+void ERTS_POLL_EXPORT(erts_poll_info)(ErtsPollSet *ps,
+                                      ErtsPollInfo *info);
+/**
+ * Get information about which events are currently selected.
+ *
+ * The unix fd is used to index into the array, so naturally this function does
+ * not work on windows. If the pollset cannot figure out what the selected
+ * events for a given fd is, it is set to ERTS_POLL_EV_NONE.
+ *
+ * @param ps the pollset to get events from
+ * @param evts an array of which events are selected on.
+ */
+void ERTS_POLL_EXPORT(erts_poll_get_selected_events)(ErtsPollSet *ps,
+                                                     ErtsPollEvents evts[],
+                                                     int length);
+
+#ifdef ERTS_ENABLE_LOCK_COUNT
+/**
+ * Enable lock counting of any locks within the pollset.
+ */
+void ERTS_POLL_EXPORT(erts_lcnt_enable_pollset_lock_count)(ErtsPollSet *, int enable);
+#endif
diff --git a/erts/emulator/sys/common/erl_sys_common_misc.c b/erts/emulator/sys/common/erl_sys_common_misc.c
index 79f87eb3a9..420138ff0a 100644
--- a/erts/emulator/sys/common/erl_sys_common_misc.c
+++ b/erts/emulator/sys/common/erl_sys_common_misc.c
@@ -45,14 +45,6 @@
 #endif
 #endif
 
-/*
- * erts_check_io_time is used by the erl_check_io implementation. The
- * global erts_check_io_time variable is declared here since there
- * (often) exist two versions of erl_check_io (kernel-poll and
- * non-kernel-poll), and we dont want two versions of this variable.
- */
-erts_smp_atomic_t erts_check_io_time;
-
 /* Written once and only once */
 
 static int filename_encoding = ERL_FILENAME_UNKNOWN;
diff --git a/erts/emulator/sys/unix/erl_unix_sys.h b/erts/emulator/sys/unix/erl_unix_sys.h
index b83837a7d2..b6f5b319ee 100644
--- a/erts/emulator/sys/unix/erl_unix_sys.h
+++ b/erts/emulator/sys/unix/erl_unix_sys.h
@@ -132,10 +132,6 @@
 /* File descriptors are numbers anc consecutively allocated on Unix */
 #define  ERTS_SYS_CONTINOUS_FD_NUMBERS
 
-#ifndef ERTS_SMP
-#  undef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
-#  define ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
-#endif
 
 typedef void *GETENV_STATE;
 
@@ -358,9 +354,7 @@ extern void erts_sys_unix_later_init(void);
 #ifdef NO_FPE_SIGNALS
 
 #define erts_get_current_fp_exception() NULL
-#ifdef ERTS_SMP
 #define erts_thread_init_fp_exception() do{}while(0)
-#endif
 #  define __ERTS_FP_CHECK_INIT(fpexnp) do {} while (0)
 #  define __ERTS_FP_ERROR(fpexnp, f, Action) if (!isfinite(f)) { Action; } else {}
 #  define __ERTS_FP_ERROR_THOROUGH(fpexnp, f, Action) __ERTS_FP_ERROR(fpexnp, f, Action)
@@ -373,9 +367,7 @@ extern void erts_sys_unix_later_init(void);
 #else /* !NO_FPE_SIGNALS */
 
 extern volatile unsigned long *erts_get_current_fp_exception(void);
-#ifdef ERTS_SMP
 extern void erts_thread_init_fp_exception(void);
-#endif
 #  if (defined(__i386__) || defined(__x86_64__)) && defined(__GNUC__)
 #    define erts_fwait(fpexnp,f) \
 	__asm__ __volatile__("fwait" : "=m"(*(fpexnp)) : "m"(f))
@@ -442,10 +434,8 @@ void erts_sys_unblock_fpe(int);
 
 
 /* Threads */
-#ifdef USE_THREADS
 extern int init_async(int);
 extern int exit_async(void);
-#endif
 
 #define ERTS_EXIT_AFTER_DUMP _exit
 
diff --git a/erts/emulator/sys/unix/sys.c b/erts/emulator/sys/unix/sys.c
index c1fa660cf9..6315135151 100644
--- a/erts/emulator/sys/unix/sys.c
+++ b/erts/emulator/sys/unix/sys.c
@@ -58,14 +58,12 @@
 #define __DARWIN__ 1
 #endif
 
-#ifdef USE_THREADS
 #include "erl_threads.h"
-#endif
 
 #include "erl_mseg.h"
 
 extern char **environ;
-erts_smp_rwmtx_t environ_rwmtx;
+erts_rwmtx_t environ_rwmtx;
 
 #define MAX_VSIZE 16		/* Max number of entries allowed in an I/O
 				 * vector sock_sendv().
@@ -94,19 +92,12 @@ extern void erts_sys_init_float(void);
 static int debug_log = 0;
 #endif
 
-#ifdef ERTS_SMP
-static erts_smp_atomic32_t have_prepared_crash_dump;
-#define ERTS_PREPARED_CRASH_DUMP \
-  ((int) erts_smp_atomic32_xchg_nob(&have_prepared_crash_dump, 1))
-#else
-static volatile int have_prepared_crash_dump;
+static erts_atomic32_t have_prepared_crash_dump;
 #define ERTS_PREPARED_CRASH_DUMP \
-  (have_prepared_crash_dump++)
-#endif
+  ((int) erts_atomic32_xchg_nob(&have_prepared_crash_dump, 1))
 
-erts_smp_atomic_t sys_misc_mem_sz;
+erts_atomic_t sys_misc_mem_sz;
 
-#if defined(ERTS_SMP)
 static void smp_sig_notify(int signum);
 static int sig_notify_fds[2] = {-1, -1};
 
@@ -114,7 +105,6 @@ static int sig_notify_fds[2] = {-1, -1};
 static int sig_suspend_fds[2] = {-1, -1};
 #endif
 
-#endif
 
 jmp_buf erts_sys_sigsegv_jmp;
 
@@ -128,38 +118,12 @@ static int max_files = -1;
 /* 
  * a few variables used by the break handler 
  */
-#ifdef ERTS_SMP
-erts_smp_atomic32_t erts_break_requested;
+erts_atomic32_t erts_break_requested;
 #define ERTS_SET_BREAK_REQUESTED \
-  erts_smp_atomic32_set_nob(&erts_break_requested, (erts_aint32_t) 1)
+  erts_atomic32_set_nob(&erts_break_requested, (erts_aint32_t) 1)
 #define ERTS_UNSET_BREAK_REQUESTED \
-  erts_smp_atomic32_set_nob(&erts_break_requested, (erts_aint32_t) 0)
-#else
-volatile int erts_break_requested = 0;
-#define ERTS_SET_BREAK_REQUESTED (erts_break_requested = 1)
-#define ERTS_UNSET_BREAK_REQUESTED (erts_break_requested = 0)
-#endif
+  erts_atomic32_set_nob(&erts_break_requested, (erts_aint32_t) 0)
 
-#ifndef ERTS_SMP
-static Eterm signalstate_sigterm[] = {
-    am_sigint,   /* 0 */
-    am_sighup,   /* 1 */
-    am_sigquit,  /* 2 */
-    am_sigabrt,  /* 3 */
-    am_sigalrm,  /* 4 */
-    am_sigterm,  /* 5 */
-    am_sigusr1,  /* 6 */
-    am_sigusr2,  /* 7 */
-    am_sigchld,  /* 8 */
-    am_sigstop,  /* 9 */
-    am_sigtstp   /* 10 */
-};
-
-volatile Uint erts_signal_state = 0;
-#define ERTS_SET_SIGNAL_STATE(S) (erts_signal_state |= signum_to_signalstate(S))
-#define ERTS_CLEAR_SIGNAL_STATE (erts_signal_state = 0)
-static ERTS_INLINE Uint signum_to_signalstate(int signum);
-#endif
 
 /* set early so the break handler has access to initial mode */
 static struct termios initial_tty_mode;
@@ -167,137 +131,6 @@ static int replace_intr = 0;
 /* assume yes initially, ttsl_init will clear it */
 int using_oldshell = 1;
 
-#ifdef ERTS_ENABLE_KERNEL_POLL
-
-int erts_use_kernel_poll = 0;
-
-struct {
-    int (*select)(ErlDrvPort, ErlDrvEvent, int, int);
-    int (*enif_select)(ErlNifEnv*, ErlNifEvent, enum ErlNifSelectFlags, void*, const ErlNifPid*, Eterm);
-    int (*event)(ErlDrvPort, ErlDrvEvent, ErlDrvEventData);
-    void (*check_io_as_interrupt)(void);
-    void (*check_io_interrupt)(int);
-    void (*check_io_interrupt_tmd)(int, ErtsMonotonicTime);
-    void (*check_io)(int);
-    Uint (*size)(void);
-    Eterm (*info)(void *);
-    int (*check_io_debug)(ErtsCheckIoDebugInfo *);
-} io_func = {0};
-
-
-int
-driver_select(ErlDrvPort port, ErlDrvEvent event, int mode, int on)
-{
-    return (*io_func.select)(port, event, mode, on);
-}
-
-int
-driver_event(ErlDrvPort port, ErlDrvEvent event, ErlDrvEventData event_data)
-{
-    return (*io_func.event)(port, event, event_data);
-}
-
-int enif_select(ErlNifEnv* env, ErlNifEvent event,
-                enum ErlNifSelectFlags flags, void* obj, const ErlNifPid* pid, Eterm ref)
-{
-    return (*io_func.enif_select)(env, event, flags, obj, pid, ref);
-}
-
-
-Eterm erts_check_io_info(void *p)
-{
-    return (*io_func.info)(p);
-}
-
-int
-erts_check_io_debug(ErtsCheckIoDebugInfo *ip)
-{
-    return (*io_func.check_io_debug)(ip);
-}
-
-
-static void
-init_check_io(void)
-{
-    if (erts_use_kernel_poll) {
-	io_func.select			= driver_select_kp;
-        io_func.enif_select		= enif_select_kp;
-	io_func.event			= driver_event_kp;
-#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
-	io_func.check_io_as_interrupt	= erts_check_io_async_sig_interrupt_kp;
-#endif
-	io_func.check_io_interrupt	= erts_check_io_interrupt_kp;
-	io_func.check_io_interrupt_tmd	= erts_check_io_interrupt_timed_kp;
-	io_func.check_io		= erts_check_io_kp;
-	io_func.size			= erts_check_io_size_kp;
-	io_func.info			= erts_check_io_info_kp;
-	io_func.check_io_debug		= erts_check_io_debug_kp;
-	erts_init_check_io_kp();
-	max_files = erts_check_io_max_files_kp();
-    }
-    else {
-	io_func.select			= driver_select_nkp;
-        io_func.enif_select		= enif_select_nkp;
-	io_func.event			= driver_event_nkp;
-#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
-	io_func.check_io_as_interrupt	= erts_check_io_async_sig_interrupt_nkp;
-#endif
-	io_func.check_io_interrupt	= erts_check_io_interrupt_nkp;
-	io_func.check_io_interrupt_tmd	= erts_check_io_interrupt_timed_nkp;
-	io_func.check_io		= erts_check_io_nkp;
-	io_func.size			= erts_check_io_size_nkp;
-	io_func.info			= erts_check_io_info_nkp;
-	io_func.check_io_debug		= erts_check_io_debug_nkp;
-	erts_init_check_io_nkp();
-	max_files = erts_check_io_max_files_nkp();
-    }
-}
-
-#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
-#define ERTS_CHK_IO_AS_INTR()	(*io_func.check_io_as_interrupt)()
-#else
-#define ERTS_CHK_IO_AS_INTR()	(*io_func.check_io_interrupt)(1)
-#endif
-#define ERTS_CHK_IO_INTR	(*io_func.check_io_interrupt)
-#define ERTS_CHK_IO_INTR_TMD	(*io_func.check_io_interrupt_tmd)
-#define ERTS_CHK_IO		(*io_func.check_io)
-#define ERTS_CHK_IO_SZ		(*io_func.size)
-
-#else /* !ERTS_ENABLE_KERNEL_POLL */
-
-static void
-init_check_io(void)
-{
-    erts_init_check_io();
-    max_files = erts_check_io_max_files();
-}
-
-#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
-#define ERTS_CHK_IO_AS_INTR()	erts_check_io_async_sig_interrupt()
-#else
-#define ERTS_CHK_IO_AS_INTR()	erts_check_io_interrupt(1)
-#endif
-#define ERTS_CHK_IO_INTR	erts_check_io_interrupt
-#define ERTS_CHK_IO_INTR_TMD	erts_check_io_interrupt_timed
-#define ERTS_CHK_IO		erts_check_io
-#define ERTS_CHK_IO_SZ		erts_check_io_size
-
-#endif
-
-void
-erts_sys_schedule_interrupt(int set)
-{
-    ERTS_CHK_IO_INTR(set);
-}
-
-#ifdef ERTS_SMP
-void
-erts_sys_schedule_interrupt_timed(int set, ErtsMonotonicTime timeout_time)
-{
-    ERTS_CHK_IO_INTR_TMD(set, timeout_time);
-}
-#endif
-
 UWord
 erts_sys_get_page_size(void)
 {
@@ -313,8 +146,8 @@ erts_sys_get_page_size(void)
 Uint
 erts_sys_misc_mem_sz(void)
 {
-    Uint res = ERTS_CHK_IO_SZ();
-    res += erts_smp_atomic_read_mb(&sys_misc_mem_sz);
+    Uint res = erts_check_io_size();
+    res += erts_atomic_read_mb(&sys_misc_mem_sz);
     return res;
 }
 
@@ -339,7 +172,6 @@ MALLOC_USE_HASH(1);
 #endif
 #endif
 
-#ifdef USE_THREADS
 
 #ifdef ERTS_THR_HAVE_SIG_FUNCS
 
@@ -418,19 +250,15 @@ thr_create_prepare_child(void *vtcdp)
     erts_sched_bind_atthrcreate_child(tcdp->sched_bind_data);
 }
 
-#endif /* #ifdef USE_THREADS */
 
 void
 erts_sys_pre_init(void)
 {
-#ifdef USE_THREADS
     erts_thr_init_data_t eid = ERTS_THR_INIT_DATA_DEF_INITER;
-#endif
 
     erts_printf_add_cr_to_stdout = 1;
     erts_printf_add_cr_to_stderr = 1;
 
-#ifdef USE_THREADS
 
     eid.thread_create_child_func = thr_create_prepare_child;
     /* Before creation in parent */
@@ -452,23 +280,15 @@ erts_sys_pre_init(void)
     erts_lc_init();
 #endif
 
-#endif /* USE_THREADS */
 
     erts_init_sys_time_sup();
 
-#ifdef USE_THREADS
 
-#ifdef ERTS_SMP
-    erts_smp_atomic32_init_nob(&erts_break_requested, 0);
-    erts_smp_atomic32_init_nob(&have_prepared_crash_dump, 0);
-#else
-    erts_break_requested = 0;
-    have_prepared_crash_dump = 0;
-#endif
+    erts_atomic32_init_nob(&erts_break_requested, 0);
+    erts_atomic32_init_nob(&have_prepared_crash_dump, 0);
 
-#endif /* USE_THREADS */
 
-    erts_smp_atomic_init_nob(&sys_misc_mem_sz, 0);
+    erts_atomic_init_nob(&sys_misc_mem_sz, 0);
 
     {
       /*
@@ -531,10 +351,8 @@ SIGFUNC sys_signal(int sig, SIGFUNC func)
     return(oact.sa_handler);
 }
 
-#ifdef USE_THREADS
 #undef  sigprocmask
 #define sigprocmask erts_thr_sigmask
-#endif
 
 void sys_sigblock(int sig)
 {
@@ -672,7 +490,7 @@ static void signal_notify_requested(Eterm type) {
         erts_queue_message(p, locks, msgp, msg, am_system);
 
         if (locks)
-            erts_smp_proc_unlock(p, locks);
+            erts_proc_unlock(p, locks);
         erts_proc_dec_refc(p);
     }
 }
@@ -685,23 +503,17 @@ break_requested(void)
    * just set a flag - checked for and handled by
    * scheduler threads erts_check_io() (not signal handler).
    */
-#ifdef DEBUG			
-  fprintf(stderr,"break!\n");
-#endif
   if (ERTS_BREAK_REQUESTED)
       erts_exit(ERTS_INTR_EXIT, "");
 
   ERTS_SET_BREAK_REQUESTED;
-  ERTS_CHK_IO_AS_INTR(); /* Make sure we don't sleep in poll */
+  /* Wake aux thread to get handle break */
+  erts_aux_thread_poke();
 }
 
 static RETSIGTYPE request_break(int signum)
 {
-#ifdef ERTS_SMP
     smp_sig_notify(signum);
-#else
-    break_requested();
-#endif
 }
 
 #ifdef ETHR_UNUSABLE_SIGUSRX
@@ -789,8 +601,6 @@ signalterm_to_signum(Eterm signal)
     }
 }
 
-#ifdef ERTS_SMP
-
 static ERTS_INLINE Eterm
 signum_to_signalterm(int signum)
 {
@@ -812,37 +622,9 @@ signum_to_signalterm(int signum)
     }
 }
 
-#endif
-
-#ifndef ERTS_SMP
-static ERTS_INLINE Uint
-signum_to_signalstate(int signum)
-{
-    switch (signum) {
-    case SIGINT:  return (1 <<  0);
-    case SIGHUP:  return (1 <<  1);
-    case SIGQUIT: return (1 <<  2);
-    case SIGABRT: return (1 <<  3);
-    case SIGALRM: return (1 <<  4);
-    case SIGTERM: return (1 <<  5);
-    case SIGUSR1: return (1 <<  6);
-    case SIGUSR2: return (1 <<  7);
-    case SIGCHLD: return (1 <<  8);
-    case SIGSTOP: return (1 <<  9);
-    case SIGTSTP: return (1 << 10);
-    default:      return 0;
-    }
-}
-#endif
-
 static RETSIGTYPE generic_signal_handler(int signum)
 {
-#ifdef ERTS_SMP
     smp_sig_notify(signum);
-#else
-    ERTS_SET_SIGNAL_STATE(signum);
-    ERTS_CHK_IO_AS_INTR(); /* Make sure we don't sleep in poll */
-#endif
 }
 
 int erts_set_signal(Eterm signal, Eterm type) {
@@ -914,7 +696,7 @@ erts_sys_unix_later_init(void)
 
 int sys_max_files(void)
 {
-   return(max_files);
+   return max_files;
 }
 
 /************************** OS info *******************************/
@@ -969,7 +751,7 @@ void os_version(int *pMajor, int *pMinor, int *pBuild) {
 
 void init_getenv_state(GETENV_STATE *state)
 {
-   erts_smp_rwmtx_rlock(&environ_rwmtx);
+   erts_rwmtx_rlock(&environ_rwmtx);
    *state = NULL;
 }
 
@@ -978,7 +760,7 @@ char *getenv_string(GETENV_STATE *state0)
    char **state = (char **) *state0;
    char *cp;
 
-   ERTS_SMP_LC_ASSERT(erts_smp_lc_rwmtx_is_rlocked(&environ_rwmtx));
+   ERTS_LC_ASSERT(erts_lc_rwmtx_is_rlocked(&environ_rwmtx));
 
    if (state == NULL)
       state = environ;
@@ -992,7 +774,7 @@ char *getenv_string(GETENV_STATE *state0)
 void fini_getenv_state(GETENV_STATE *state)
 {
    *state = NULL;
-   erts_smp_rwmtx_runlock(&environ_rwmtx);
+   erts_rwmtx_runlock(&environ_rwmtx);
 }
 
 void erts_do_break_handling(void)
@@ -1005,7 +787,7 @@ void erts_do_break_handling(void)
      * therefore, make sure that all threads but this one are blocked before
      * proceeding!
      */
-    erts_smp_thr_progress_block();
+    erts_thr_progress_block();
 
     /* during break we revert to initial settings */
     /* this is done differently for oldshell */
@@ -1033,25 +815,9 @@ void erts_do_break_handling(void)
       tcsetattr(0,TCSANOW,&temp_mode);
     }
 
-    erts_smp_thr_progress_unblock();
+    erts_thr_progress_unblock();
 }
 
-#ifdef ERTS_SIGNAL_STATE
-void erts_handle_signal_state(void) {
-    Uint signal_state = ERTS_SIGNAL_STATE;
-    Uint i = 0;
-
-    ERTS_CLEAR_SIGNAL_STATE;
-
-    while (signal_state) {
-        if (signal_state & 0x1) {
-            signal_notify_requested(signalstate_sigterm[i]);
-        }
-        i++;
-        signal_state = signal_state >> 1;
-    }
-}
-#endif
 
 /* Fills in the systems representation of the jam/beam process identifier.
 ** The Pid is put in STRING representation in the supplied buffer,
@@ -1079,14 +845,14 @@ erts_sys_putenv(char *key, char *value)
     env = erts_alloc(ERTS_ALC_T_TMP, need);
 #else
     env = erts_alloc(ERTS_ALC_T_PUTENV_STR, need);
-    erts_smp_atomic_add_nob(&sys_misc_mem_sz, need);
+    erts_atomic_add_nob(&sys_misc_mem_sz, need);
 #endif
     strcpy(env,key);
     strcat(env,"=");
     strcat(env,value);
-    erts_smp_rwmtx_rwlock(&environ_rwmtx);
+    erts_rwmtx_rwlock(&environ_rwmtx);
     res = putenv(env);
-    erts_smp_rwmtx_rwunlock(&environ_rwmtx);
+    erts_rwmtx_rwunlock(&environ_rwmtx);
 #ifdef HAVE_COPYING_PUTENV
     erts_free(ERTS_ALC_T_TMP, env);
 #endif
@@ -1133,9 +899,9 @@ int
 erts_sys_getenv(char *key, char *value, size_t *size)
 {
     int res;
-    erts_smp_rwmtx_rlock(&environ_rwmtx);
+    erts_rwmtx_rlock(&environ_rwmtx);
     res = erts_sys_getenv__(key, value, size);
-    erts_smp_rwmtx_runlock(&environ_rwmtx);
+    erts_rwmtx_runlock(&environ_rwmtx);
     return res;
 }
 
@@ -1143,9 +909,9 @@ int
 erts_sys_unsetenv(char *key)
 {
     int res;
-    erts_smp_rwmtx_rwlock(&environ_rwmtx);
+    erts_rwmtx_rwlock(&environ_rwmtx);
     res = unsetenv(key);
-    erts_smp_rwmtx_rwunlock(&environ_rwmtx);
+    erts_rwmtx_rwunlock(&environ_rwmtx);
     return res;
 }
 
@@ -1286,16 +1052,6 @@ erl_assert_error(const char* expr, const char* func, const char* file, int line)
     fprintf(stderr, "%s:%d:%s() Assertion failed: %s\n",
             file, line, func, expr);
     fflush(stderr);
-#if !defined(ERTS_SMP) && 0
-    /* Writing a crashdump from a failed assertion when smp support
-     * is enabled almost a guaranteed deadlocking, don't even bother.
-     *
-     * It could maybe be useful (but I'm not convinced) to write the
-     * crashdump if smp support is disabled...
-     */
-    if (erts_initialized)
-	erl_crash_dump(file, line, "Assertion failed: %s\n", expr);
-#endif
     abort();
 }
 
@@ -1317,22 +1073,7 @@ erl_debug(char* fmt, ...)
 
 #endif /* DEBUG */
 
-/*
- * Called from schedule() when it runs out of runnable processes,
- * or when Erlang code has performed INPUT_REDUCTIONS reduction
- * steps. runnable == 0 iff there are no runnable Erlang processes.
- */
-void
-erl_sys_schedule(int runnable)
-{
-    ERTS_CHK_IO(!runnable);
-    ERTS_SMP_LC_ASSERT(!erts_thr_progress_is_blocking());
-}
-
-
-#ifdef ERTS_SMP
-
-static erts_smp_tid_t sig_dispatcher_tid;
+static erts_tid_t sig_dispatcher_tid;
 
 static void
 smp_sig_notify(int signum)
@@ -1406,7 +1147,7 @@ signal_dispatcher_thread_func(void *unused)
                 }
                 signal_notify_requested(signal);
         }
-        ERTS_SMP_LC_ASSERT(!erts_thr_progress_is_blocking());
+        ERTS_LC_ASSERT(!erts_thr_progress_is_blocking());
     }
     return NULL;
 }
@@ -1414,7 +1155,7 @@ signal_dispatcher_thread_func(void *unused)
 static void
 init_smp_sig_notify(void)
 {
-    erts_smp_thr_opts_t thr_opts = ERTS_SMP_THR_OPTS_DEFAULT_INITER;
+    erts_thr_opts_t thr_opts = ERTS_THR_OPTS_DEFAULT_INITER;
     thr_opts.detached = 1;
     thr_opts.name = "sys_sig_dispatcher";
 
@@ -1426,7 +1167,7 @@ init_smp_sig_notify(void)
     }
 
     /* Start signal handler thread */
-    erts_smp_thr_create(&sig_dispatcher_tid,
+    erts_thr_create(&sig_dispatcher_tid,
 			signal_dispatcher_thread_func,
 			NULL,
 			&thr_opts);
@@ -1519,103 +1260,19 @@ erts_sys_main_thread(void)
     }
 }
 
-#endif /* ERTS_SMP */
-
-#ifdef ERTS_ENABLE_KERNEL_POLL /* get_value() is currently only used when
-				  kernel-poll is enabled */
-
-/* Get arg marks argument as handled by
-   putting NULL in argv */
-static char *
-get_value(char* rest, char** argv, int* ip)
-{
-    char *param = argv[*ip]+1;
-    argv[*ip] = NULL;
-    if (*rest == '\0') {
-	char *next = argv[*ip + 1];
-	if (next[0] == '-'
-	    && next[1] == '-'
-	    &&  next[2] == '\0') {
-	    erts_fprintf(stderr, "bad \"%s\" value: \n", param);
-	    erts_usage();
-	}
-	(*ip)++;
-	argv[*ip] = NULL;
-	return next;
-    }
-    return rest;
-}
-
-#endif /* ERTS_ENABLE_KERNEL_POLL */
 
 void
 erl_sys_args(int* argc, char** argv)
 {
-    int i, j;
 
-    erts_smp_rwmtx_init(&environ_rwmtx, "environ", NIL,
+    erts_rwmtx_init(&environ_rwmtx, "environ", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
 
-    i = 1;
-
     ASSERT(argc && argv);
 
-    while (i < *argc) {
-	if(argv[i][0] == '-') {
-	    switch (argv[i][1]) {
-#ifdef ERTS_ENABLE_KERNEL_POLL
-	    case 'K': {
-		char *arg = get_value(argv[i] + 2, argv, &i);
-		if (strcmp("true", arg) == 0) {
-		    erts_use_kernel_poll = 1;
-		}
-		else if (strcmp("false", arg) == 0) {
-		    erts_use_kernel_poll = 0;
-		}
-		else {
-		    erts_fprintf(stderr, "bad \"K\" value: %s\n", arg);
-		    erts_usage();
-		}
-		break;
-	    }
-#endif
-	    case '-':
-		goto done_parsing;
-	    default:
-		break;
-	    }
-	}
-	i++;
-    }
-
- done_parsing:
-
-#ifdef ERTS_ENABLE_KERNEL_POLL
-    if (erts_use_kernel_poll) {
-	char no_kp[10];
-	size_t no_kp_sz = sizeof(no_kp);
-	int res = erts_sys_getenv_raw("ERL_NO_KERNEL_POLL", no_kp, &no_kp_sz);
-	if (res > 0
-	    || (res == 0
-		&& sys_strcmp("false", no_kp) != 0
-		&& sys_strcmp("FALSE", no_kp) != 0)) {
-	    erts_use_kernel_poll = 0;
-	}
-    }
-#endif
-
-    init_check_io();
+    max_files = erts_check_io_max_files();
 
-#ifdef ERTS_SMP
     init_smp_sig_notify();
     init_smp_sig_suspend();
-#endif
 
-    /* Handled arguments have been marked with NULL. Slide arguments
-       not handled towards the beginning of argv. */
-    for (i = 0, j = 0; i < *argc; i++) {
-	if (argv[i])
-	    argv[j++] = argv[i];
-    }
-    *argc = j;
 }
diff --git a/erts/emulator/sys/unix/sys_drivers.c b/erts/emulator/sys/unix/sys_drivers.c
index 834706d86f..0228e1af54 100644
--- a/erts/emulator/sys/unix/sys_drivers.c
+++ b/erts/emulator/sys/unix/sys_drivers.c
@@ -53,14 +53,12 @@
 #define WANT_NONBLOCKING    /* must define this to pull in defs from sys.h */
 #include "sys.h"
 
-#ifdef USE_THREADS
 #include "erl_threads.h"
-#endif
 
 extern char **environ;
-extern erts_smp_rwmtx_t environ_rwmtx;
+extern erts_rwmtx_t environ_rwmtx;
 
-extern erts_smp_atomic_t sys_misc_mem_sz;
+extern erts_atomic_t sys_misc_mem_sz;
 
 static Eterm forker_port;
 
@@ -86,12 +84,6 @@ static Eterm forker_port;
 #define MAXIOV 16
 #endif
 
-#ifdef USE_THREADS
-#  define FDBLOCK 1
-#else
-#  define FDBLOCK 0
-#endif
-
 /* Used by the fd driver iff the fd could not be set to non-blocking */
 typedef struct ErtsSysBlocking_ {
     ErlDrvPDL pdl;
@@ -178,9 +170,7 @@ void
 erl_sys_late_init(void)
 {
     SysDriverOpts opts;
-#ifdef ERTS_SMP
     Port *port;
-#endif
 
     sys_signal(SIGPIPE, SIG_IGN); /* Ignore - we'll handle the write failure */
 
@@ -197,13 +187,9 @@ erl_sys_late_init(void)
     opts.argv = NULL;
     opts.parallelism = erts_port_parallelism;
 
-#ifdef ERTS_SMP
     port =
-#endif
         erts_open_driver(&forker_driver, make_internal_pid(0), "forker", &opts, NULL, NULL);
-#ifdef ERTS_SMP
     erts_mtx_unlock(port->lock);
-#endif
     erts_sys_unix_later_init(); /* Need to be called after forker has been started */
 }
 
@@ -220,10 +206,8 @@ static ErlDrvData vanilla_start(ErlDrvPort, char*, SysDriverOpts*);
 
 /* II.III FD prototypes */
 static ErlDrvData fd_start(ErlDrvPort, char*, SysDriverOpts*);
-#if FDBLOCK
 static void fd_async(void *);
 static void fd_ready_async(ErlDrvData drv_data, ErlDrvThreadData thread_data);
-#endif
 static ErlDrvSSizeT fd_control(ErlDrvData, unsigned int, char *, ErlDrvSizeT,
 			       char **, ErlDrvSizeT);
 static void fd_stop(ErlDrvData);
@@ -287,11 +271,7 @@ struct erl_drv_entry fd_driver_entry = {
     fd_control,
     NULL,
     outputv,
-#if FDBLOCK
     fd_ready_async, /* ready_async */
-#else
-    NULL,
-#endif
     fd_flush, /* flush */
     NULL, /* call */
     NULL, /* event */
@@ -363,7 +343,7 @@ static int set_blocking_data(ErtsSysDriverData *dd) {
 
     dd->blocking = erts_alloc(ERTS_ALC_T_SYS_BLOCKING, sizeof(ErtsSysBlocking));
 
-    erts_smp_atomic_add_nob(&sys_misc_mem_sz, sizeof(ErtsSysBlocking));
+    erts_atomic_add_nob(&sys_misc_mem_sz, sizeof(ErtsSysBlocking));
 
     dd->blocking->pdl = driver_pdl_create(dd->port_num);
     dd->blocking->res = 0;
@@ -406,7 +386,7 @@ create_driver_data(ErlDrvPort port_num,
         size += sizeof(ErtsSysFdData);
 
     data = erts_alloc(ERTS_ALC_T_DRV_TAB,size);
-    erts_smp_atomic_add_nob(&sys_misc_mem_sz, size);
+    erts_atomic_add_nob(&sys_misc_mem_sz, size);
 
     driver_data = (ErtsSysDriverData*)data;
     data += sizeof(*driver_data);
@@ -441,7 +421,7 @@ create_driver_data(ErlDrvPort port_num,
             data += sizeof(*driver_data->ofd);
             init_fd_data(driver_data->ofd, ofd);
         }
-        if (is_blocking && FDBLOCK)
+        if (is_blocking)
             if (!set_blocking_data(driver_data)) {
                 erts_free(ERTS_ALC_T_DRV_TAB, driver_data);
                 return NULL;
@@ -472,7 +452,7 @@ static char **build_unix_environment(char *block)
     char **cpp;
     char** old_env;
     
-    ERTS_SMP_LC_ASSERT(erts_smp_lc_rwmtx_is_rlocked(&environ_rwmtx));
+    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rlocked(&environ_rwmtx));
 
     cp = block;
     len = 0;
@@ -620,12 +600,12 @@ static ErlDrvData spawn_start(ErlDrvPort port_num, char* name,
 	len = CMD_LINE_PREFIX_STR_SZ + len + 1;
     }
 
-    erts_smp_rwmtx_rlock(&environ_rwmtx);
+    erts_rwmtx_rlock(&environ_rwmtx);
 
     if (opts->envir == NULL) {
 	new_environ = environ;
     } else if ((new_environ = build_unix_environment(opts->envir)) == NULL) {
-	erts_smp_rwmtx_runlock(&environ_rwmtx);
+	erts_rwmtx_runlock(&environ_rwmtx);
         close_pipes(ifd, ofd);
 	erts_free(ERTS_ALC_T_TMP, (void *) cmd_line);
 	errno = ENOMEM;
@@ -641,7 +621,7 @@ static ErlDrvData spawn_start(ErlDrvPort port_num, char* name,
         erts_free(ERTS_ALC_T_TMP, (void *) cmd_line);
         if (new_environ != environ)
             erts_free(ERTS_ALC_T_ENVIRONMENT, (void *) new_environ);
-        erts_smp_rwmtx_runlock(&environ_rwmtx);
+        erts_rwmtx_runlock(&environ_rwmtx);
         errno = err;
         return ERL_DRV_ERROR_ERRNO;
     }
@@ -681,7 +661,7 @@ static ErlDrvData spawn_start(ErlDrvPort port_num, char* name,
 
         if (!io_vector) {
             close_pipes(ifd, ofd);
-            erts_smp_rwmtx_runlock(&environ_rwmtx);
+            erts_rwmtx_runlock(&environ_rwmtx);
             erts_free(ERTS_ALC_T_TMP, (void *) cmd_line);
             if (new_environ != environ)
                 erts_free(ERTS_ALC_T_ENVIRONMENT, (void *) new_environ);
@@ -766,7 +746,7 @@ static ErlDrvData spawn_start(ErlDrvPort port_num, char* name,
                 erts_free(ERTS_ALC_T_TMP, io_vector);
                 if (new_environ != environ)
                     erts_free(ERTS_ALC_T_ENVIRONMENT, (void *) new_environ);
-                erts_smp_rwmtx_runlock(&environ_rwmtx);
+                erts_rwmtx_runlock(&environ_rwmtx);
                 erts_free(ERTS_ALC_T_TMP, (void *) cmd_line);
                 errno = err;
                 return ERL_DRV_ERROR_ERRNO;
@@ -795,7 +775,7 @@ static ErlDrvData spawn_start(ErlDrvPort port_num, char* name,
     if (new_environ != environ)
 	erts_free(ERTS_ALC_T_ENVIRONMENT, (void *) new_environ);
 
-    erts_smp_rwmtx_runlock(&environ_rwmtx);
+    erts_rwmtx_runlock(&environ_rwmtx);
 
     dd = create_driver_data(port_num, ifd[0], ofd[1], opts->packet_bytes,
                              DO_WRITE | DO_READ, opts->exit_status,
@@ -1068,8 +1048,8 @@ static void clear_fd_data(ErtsSysFdData *fdd)
 {
     if (fdd->sz > 0) {
 	erts_free(ERTS_ALC_T_FD_ENTRY_BUF, (void *) fdd->buf);
-	ASSERT(erts_smp_atomic_read_nob(&sys_misc_mem_sz) >= fdd->sz);
-	erts_smp_atomic_add_nob(&sys_misc_mem_sz, -1*fdd->sz);
+	ASSERT(erts_atomic_read_nob(&sys_misc_mem_sz) >= fdd->sz);
+	erts_atomic_add_nob(&sys_misc_mem_sz, -1*fdd->sz);
     }
     fdd->buf = NULL;
     fdd->sz = 0;
@@ -1092,13 +1072,11 @@ static void fd_stop(ErlDrvData ev)  /* Does not close the fds */
     ErlDrvPort prt = dd->port_num;
     int sz = sizeof(ErtsSysDriverData);
 
-#if FDBLOCK
     if (dd->blocking) {
         erts_free(ERTS_ALC_T_SYS_BLOCKING, dd->blocking);
         dd->blocking = NULL;
         sz += sizeof(ErtsSysBlocking);
     }
-#endif
 
     if (dd->ifd) {
         sz += sizeof(ErtsSysFdData);
@@ -1110,7 +1088,7 @@ static void fd_stop(ErlDrvData ev)  /* Does not close the fds */
     }
 
      erts_free(ERTS_ALC_T_DRV_TAB, dd);
-     erts_smp_atomic_add_nob(&sys_misc_mem_sz, -sz);
+     erts_atomic_add_nob(&sys_misc_mem_sz, -sz);
 }
 
 static void fd_flush(ErlDrvData ev)
@@ -1191,19 +1169,19 @@ static void outputv(ErlDrvData e, ErlIOVec* ev)
     ev->iov[0].iov_len = pb;
     ev->size += pb;
 
-    if (dd->blocking && FDBLOCK)
+    if (dd->blocking)
         driver_pdl_lock(dd->blocking->pdl);
 
     if ((sz = driver_sizeq(ix)) > 0) {
 	driver_enqv(ix, ev, 0);
 
-        if (dd->blocking && FDBLOCK)
+        if (dd->blocking)
             driver_pdl_unlock(dd->blocking->pdl);
 
 	if (sz + ev->size >= (1 << 13))
 	    set_busy_port(ix, 1);
     }
-    else if (!dd->blocking || !FDBLOCK) {
+    else if (!dd->blocking) {
         /* We try to write directly if the fd in non-blocking */
 	int vsize = ev->vsize > MAX_VSIZE ? MAX_VSIZE : ev->vsize;
 
@@ -1220,7 +1198,6 @@ static void outputv(ErlDrvData e, ErlIOVec* ev)
 	driver_enqv(ix, ev, n);  /* n is the skip value */
 	driver_select(ix, ofd, ERL_DRV_WRITE|ERL_DRV_USE, 1);
     }
-#if FDBLOCK
     else {
         if (ev->size != 0) {
             driver_enqv(ix, ev, 0);
@@ -1231,7 +1208,6 @@ static void outputv(ErlDrvData e, ErlIOVec* ev)
             driver_pdl_unlock(dd->blocking->pdl);
         }
     }
-#endif
     /* return 0;*/
 }
 
@@ -1303,7 +1279,7 @@ static int port_inp_failure(ErtsSysDriverData *dd, int res)
         clear_fd_data(dd->ifd);
     }
 
-    if (dd->blocking && FDBLOCK) {
+    if (dd->blocking) {
         driver_pdl_lock(dd->blocking->pdl);
         if (driver_sizeq(dd->port_num) > 0) {
             driver_pdl_unlock(dd->blocking->pdl);
@@ -1408,7 +1384,7 @@ static void ready_input(ErlDrvData e, ErlDrvEvent ready_fd)
 
             if (dd->ifd->fd < 0) {
                 driver_select(port_num, abs(dd->ifd->fd), ERL_DRV_READ|ERL_DRV_USE, 0);
-                erts_smp_atomic_add_nob(&sys_misc_mem_sz, -sizeof(ErtsSysFdData));
+                erts_atomic_add_nob(&sys_misc_mem_sz, -sizeof(ErtsSysFdData));
                 dd->ifd = NULL;
             }
 
@@ -1514,7 +1490,7 @@ static void ready_input(ErlDrvData e, ErlDrvEvent ready_fd)
 			port_inp_failure(dd, -1);
 		    }
 		    else {
-			erts_smp_atomic_add_nob(&sys_misc_mem_sz, h);
+			erts_atomic_add_nob(&sys_misc_mem_sz, h);
 			sys_memcpy(buf, cpos, bytes_left);
 			dd->ifd->buf = buf;
 			dd->ifd->sz = h;
@@ -1549,7 +1525,7 @@ static void ready_output(ErlDrvData e, ErlDrvEvent ready_fd)
                should close the output fd as soon as the command has
                been sent. */
             driver_select(ix, ready_fd, ERL_DRV_WRITE|ERL_DRV_USE, 0);
-            erts_smp_atomic_add_nob(&sys_misc_mem_sz, -sizeof(ErtsSysFdData));
+            erts_atomic_add_nob(&sys_misc_mem_sz, -sizeof(ErtsSysFdData));
             dd->ofd = NULL;
         }
         if (dd->terminating)
@@ -1579,7 +1555,6 @@ static void stop_select(ErlDrvEvent fd, void* _)
     close((int)fd);
 }
 
-#if FDBLOCK
 
 static void
 fd_async(void *async_data)
@@ -1658,7 +1633,6 @@ void fd_ready_async(ErlDrvData drv_data,
     return; /* 0; */
 }
 
-#endif
 
 /* Forker driver */
 
@@ -1749,8 +1723,6 @@ static ErlDrvData forker_start(ErlDrvPort port_num, char* name,
 
     SET_NONBLOCKING(forker_fd);
 
-    driver_select(port_num, forker_fd, ERL_DRV_READ|ERL_DRV_USE, 1);
-
     return (ErlDrvData)port_num;
 }
 
@@ -1847,10 +1819,19 @@ static void forker_ready_output(ErlDrvData e, ErlDrvEvent fd)
 static ErlDrvSSizeT forker_control(ErlDrvData e, unsigned int cmd, char *buf,
                                    ErlDrvSizeT len, char **rbuf, ErlDrvSizeT rlen)
 {
+    static int first_call = 1;
     ErtsSysForkerProto *proto = (ErtsSysForkerProto *)buf;
     ErlDrvPort port_num = (ErlDrvPort)e;
     int res;
 
+    if (first_call) {
+        /*
+         * Do driver_select here when schedulers and their pollsets have started.
+         */
+        driver_select(port_num, forker_fd, ERL_DRV_READ|ERL_DRV_USE, 1);
+        first_call = 0;
+    }
+
     driver_enq(port_num, buf, len);
     if (driver_sizeq(port_num) > sizeof(*proto)) {
         return 0;
diff --git a/erts/emulator/sys/unix/sys_float.c b/erts/emulator/sys/unix/sys_float.c
index 6435da086f..a82c15bd32 100644
--- a/erts/emulator/sys/unix/sys_float.c
+++ b/erts/emulator/sys/unix/sys_float.c
@@ -39,7 +39,6 @@ erts_sys_init_float(void)
 
 #else  /* !NO_FPE_SIGNALS */
 
-#ifdef ERTS_SMP
 static erts_tsd_key_t fpe_key;
 
 /* once-only initialisation early in the main thread (via erts_sys_init_float()) */
@@ -61,11 +60,6 @@ static ERTS_INLINE volatile unsigned long *erts_thread_get_fp_exception(void)
 {
     return (volatile unsigned long*)erts_tsd_get(fpe_key);
 }
-#else /* !SMP */
-#define erts_init_fp_exception()	/*empty*/
-static volatile unsigned long fp_exception;
-#define erts_thread_get_fp_exception()	(&fp_exception)
-#endif /* SMP */
 
 volatile unsigned long *erts_get_current_fp_exception(void)
 {
@@ -659,11 +653,9 @@ void erts_sys_init_float(void)
 
 void erts_thread_init_float(void)
 {
-#ifdef ERTS_SMP
     /* This allows Erlang schedulers to leave Erlang-process context
        and still have working FP exceptions. XXX: is this needed? */
     erts_thread_init_fp_exception();
-#endif
 
 #ifndef NO_FPE_SIGNALS
     /* NOTE:
diff --git a/erts/emulator/sys/unix/sys_time.c b/erts/emulator/sys/unix/sys_time.c
index 102ef7bebf..ef05380d17 100644
--- a/erts/emulator/sys/unix/sys_time.c
+++ b/erts/emulator/sys/unix/sys_time.c
@@ -160,7 +160,7 @@ struct sys_time_internal_state_read_mostly__ {
 
 #ifdef ERTS_SYS_TIME_INTERNAL_STATE_WRITE_FREQ__
 struct sys_time_internal_state_write_freq__ {
-    erts_smp_mtx_t mtx;
+    erts_mtx_t mtx;
 #if defined(__linux__) && defined(OS_MONOTONIC_TIME_USING_CLOCK_GETTIME)
     ErtsMonotonicTime last_delivered;
 #endif
@@ -304,7 +304,7 @@ sys_init_time(ErtsSysInitTimeResult *init_resp)
 	    erts_sys_time_data__.r.o.os_times =
 		clock_gettime_times_verified;
 #endif
-            erts_smp_mtx_init(&internal_state.w.f.mtx, "os_monotonic_time", NIL,
+            erts_mtx_init(&internal_state.w.f.mtx, "os_monotonic_time", NIL,
                 ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_IO);
 	    internal_state.w.f.last_delivered
 		= clock_gettime_monotonic();
@@ -525,12 +525,12 @@ static ErtsMonotonicTime clock_gettime_monotonic_verified(void)
     mtime = (ErtsMonotonicTime) posix_clock_gettime(MONOTONIC_CLOCK_ID,
 						    MONOTONIC_CLOCK_ID_STR);
 
-    erts_smp_mtx_lock(&internal_state.w.f.mtx);
+    erts_mtx_lock(&internal_state.w.f.mtx);
     if (mtime < internal_state.w.f.last_delivered)
 	mtime = internal_state.w.f.last_delivered;
     else
 	internal_state.w.f.last_delivered = mtime;
-    erts_smp_mtx_unlock(&internal_state.w.f.mtx);
+    erts_mtx_unlock(&internal_state.w.f.mtx);
 
     return mtime;
 }
@@ -547,12 +547,12 @@ static void clock_gettime_times_verified(ErtsMonotonicTime *mtimep,
 			      WALL_CLOCK_ID_STR,
 			      stimep);
 
-    erts_smp_mtx_lock(&internal_state.w.f.mtx);
+    erts_mtx_lock(&internal_state.w.f.mtx);
     if (*mtimep < internal_state.w.f.last_delivered)
 	*mtimep = internal_state.w.f.last_delivered;
     else
 	internal_state.w.f.last_delivered = *mtimep;
-    erts_smp_mtx_unlock(&internal_state.w.f.mtx);
+    erts_mtx_unlock(&internal_state.w.f.mtx);
 }
 
 #endif /* defined(OS_SYSTEM_TIME_USING_CLOCK_GETTIME) */
@@ -878,8 +878,6 @@ ErtsMonotonicTime
 erts_os_monotonic_time(void)
 {
     Uint32 ticks = get_tick_count();
-    ERTS_CHK_EXTEND_OS_MONOTONIC_TIME(&internal_state.wr.m.os_mtime_xtnd,
-				      ticks);
     return ERTS_EXTEND_OS_MONOTONIC_TIME(&internal_state.wr.m.os_mtime_xtnd,
 					 ticks) << internal_state.r.o.times_shift;
 }
diff --git a/erts/emulator/sys/win32/erl_poll.c b/erts/emulator/sys/win32/erl_poll.c
index 8743f83a50..fd4c745c3b 100644
--- a/erts/emulator/sys/win32/erl_poll.c
+++ b/erts/emulator/sys/win32/erl_poll.c
@@ -34,6 +34,7 @@
  */
 
 /*#define HARDDEBUG */
+/*#define HARDTRACE */
 #ifdef HARDDEBUG
 #ifdef HARDTRACE
 #define HARDTRACEF(X) my_debug_printf##X
@@ -50,7 +51,7 @@ static void my_debug_printf(char *fmt, ...)
     va_start(args, fmt);
     erts_vsnprintf(buffer,1024,fmt,args);
     va_end(args);
-    erts_fprintf(stderr,"%s\r\n",buffer);
+    erts_printf("%s\r\n",buffer);
 }
 #else
 #define HARDTRACEF(X)
@@ -274,53 +275,35 @@ typedef struct _Waiter {
 /*
  * The structure for a pollset. There can currently be only one...
  */
-struct ErtsPollSet_ {
+struct erts_pollset {
     Waiter** waiter;
     int allocated_waiters;  /* Size ow waiter array */ 
     int num_waiters;	    /* Number of waiter threads. */
-    int restore_events;        /* Tells us to restore waiters events 
-				  next time around */
     HANDLE event_io_ready;     /* To be used when waiting for io */
     /* These are used to wait for workers to enter standby */
     volatile int standby_wait_counter; /* Number of threads to wait for */
     CRITICAL_SECTION standby_crit;     /* CS to guard the counter */
-    HANDLE standby_wait_event;         /* Event signalled when counte == 0 */
+    HANDLE standby_wait_event;         /* Event signalled when counter == 0 */
     erts_atomic32_t wakeup_state;
-#ifdef ERTS_SMP
-    erts_smp_mtx_t mtx;
-#endif
-    erts_atomic64_t timeout_time;
+    erts_mtx_t mtx;
 };
 
-#ifdef ERTS_SMP
 
 #define ERTS_POLLSET_LOCK(PS) \
-  erts_smp_mtx_lock(&(PS)->mtx)
+  erts_mtx_lock(&(PS)->mtx)
 #define ERTS_POLLSET_UNLOCK(PS) \
-  erts_smp_mtx_unlock(&(PS)->mtx)
-
-#else
+  erts_mtx_unlock(&(PS)->mtx)
 
-#define ERTS_POLLSET_LOCK(PS)
-#define ERTS_POLLSET_UNLOCK(PS)
-
-#endif
 
 /*
  * Communication with sys_interrupt
  */
 
-#ifdef ERTS_SMP
-extern erts_smp_atomic32_t erts_break_requested;
+extern erts_atomic32_t erts_break_requested;
 #define ERTS_SET_BREAK_REQUESTED \
-  erts_smp_atomic32_set_nob(&erts_break_requested, (erts_aint32_t) 1)
+  erts_atomic32_set_nob(&erts_break_requested, (erts_aint32_t) 1)
 #define ERTS_UNSET_BREAK_REQUESTED \
-  erts_smp_atomic32_set_nob(&erts_break_requested, (erts_aint32_t) 0)
-#else
-extern volatile int erts_break_requested;
-#define ERTS_SET_BREAK_REQUESTED (erts_break_requested = 1)
-#define ERTS_UNSET_BREAK_REQUESTED (erts_break_requested = 0)
-#endif
+  erts_atomic32_set_nob(&erts_break_requested, (erts_aint32_t) 0)
 
 static erts_mtx_t break_waiter_lock;
 static HANDLE break_happened_event;
@@ -367,39 +350,19 @@ do { \
     wait_standby(PS); \
  } while(0)
 
-static ERTS_INLINE void
-init_timeout_time(ErtsPollSet ps)
-{
-    erts_atomic64_init_nob(&ps->timeout_time,
-			   (erts_aint64_t) ERTS_MONOTONIC_TIME_MAX);
-}
-
-static ERTS_INLINE void
-set_timeout_time(ErtsPollSet ps, ErtsMonotonicTime time)
-{
-    erts_atomic64_set_relb(&ps->timeout_time,
-			   (erts_aint64_t) time);
-}
-
-static ERTS_INLINE ErtsMonotonicTime
-get_timeout_time(ErtsPollSet ps)
-{
-    return (ErtsMonotonicTime) erts_atomic64_read_acqb(&ps->timeout_time);
-}
-
 #define ERTS_POLL_NOT_WOKEN		((erts_aint32_t) 0)
 #define ERTS_POLL_WOKEN_IO_READY	((erts_aint32_t) 1)
 #define ERTS_POLL_WOKEN_INTR		((erts_aint32_t) 2)
 #define ERTS_POLL_WOKEN_TIMEDOUT	((erts_aint32_t) 3)
 
 static ERTS_INLINE int
-is_io_ready(ErtsPollSet ps)
+is_io_ready(ErtsPollSet *ps)
 {
     return erts_atomic32_read_nob(&ps->wakeup_state) == ERTS_POLL_WOKEN_IO_READY;
 }
 
 static ERTS_INLINE void
-woke_up(ErtsPollSet ps)
+woke_up(ErtsPollSet *ps)
 {
     if (erts_atomic32_read_nob(&ps->wakeup_state) == ERTS_POLL_NOT_WOKEN)
 	erts_atomic32_cmpxchg_nob(&ps->wakeup_state,
@@ -422,7 +385,7 @@ woke_up(ErtsPollSet ps)
 }
 
 static ERTS_INLINE int
-wakeup_cause(ErtsPollSet ps)
+wakeup_cause(ErtsPollSet *ps)
 {
     int res;
     erts_aint32_t wakeup_state = erts_atomic32_read_acqb(&ps->wakeup_state);
@@ -445,46 +408,8 @@ wakeup_cause(ErtsPollSet ps)
     return res;
 }
 
-static ERTS_INLINE DWORD
-poll_wait_timeout(ErtsPollSet ps, ErtsMonotonicTime timeout_time)
-{
-    ErtsMonotonicTime current_time, diff_time, timeout;
-
-    if (timeout_time == ERTS_POLL_NO_TIMEOUT) {
-    no_timeout:
-	set_timeout_time(ps, ERTS_MONOTONIC_TIME_MIN);
-	woke_up(ps);
-	return (DWORD) 0;
-    }
-
-    current_time = erts_get_monotonic_time(NULL);
-    diff_time = timeout_time - current_time;
-    if (diff_time <= 0)
-	goto no_timeout;
-
-    /* Round up to nearest milli second */
-    timeout = (ERTS_MONOTONIC_TO_MSEC(diff_time - 1) + 1);
-    if (timeout > INT_MAX)
-	timeout = INT_MAX; /* Also prevents DWORD overflow */
-
-    set_timeout_time(ps, current_time + ERTS_MSEC_TO_MONOTONIC(timeout));
-
-    ResetEvent(ps->event_io_ready);
-    /*
-     * Since we don't know the internals of ResetEvent() we issue
-     * a memory barrier as a safety precaution ensuring that
-     * the load of wakeup_state wont be reordered with stores made
-     * by ResetEvent().
-     */
-    ERTS_THR_MEMORY_BARRIER;
-    if (erts_atomic32_read_nob(&ps->wakeup_state) != ERTS_POLL_NOT_WOKEN)
-	return (DWORD) 0;
-
-    return (DWORD) timeout;
-}
-
 static ERTS_INLINE void
-wake_poller(ErtsPollSet ps, int io_ready)
+wake_poller(ErtsPollSet *ps, int io_ready)
 {
     erts_aint32_t wakeup_state;
     if (io_ready) {
@@ -519,13 +444,13 @@ wake_poller(ErtsPollSet ps, int io_ready)
 }
 
 static ERTS_INLINE void
-reset_io_ready(ErtsPollSet ps)
+reset_io_ready(ErtsPollSet *ps)
 {
     erts_atomic32_set_nob(&ps->wakeup_state, ERTS_POLL_NOT_WOKEN);
 }
 
 static ERTS_INLINE void
-restore_io_ready(ErtsPollSet ps)
+restore_io_ready(ErtsPollSet *ps)
 {
     erts_atomic32_set_nob(&ps->wakeup_state, ERTS_POLL_WOKEN_IO_READY);
 }
@@ -535,13 +460,13 @@ restore_io_ready(ErtsPollSet ps)
  * notifying a poller thread about I/O ready.
  */
 static ERTS_INLINE void
-notify_io_ready(ErtsPollSet ps)
+notify_io_ready(ErtsPollSet *ps)
 {
     wake_poller(ps, 1);
 }
 
 static ERTS_INLINE void
-reset_interrupt(ErtsPollSet ps)
+reset_interrupt(ErtsPollSet *ps)
 {
     /* We need to keep io-ready if set */
     erts_aint32_t wakeup_state = erts_atomic32_read_nob(&ps->wakeup_state);
@@ -558,12 +483,12 @@ reset_interrupt(ErtsPollSet ps)
 }
 
 static ERTS_INLINE void
-set_interrupt(ErtsPollSet ps)
+set_interrupt(ErtsPollSet *ps)
 {
     wake_poller(ps, 0);
 }
 
-static void setup_standby_wait(ErtsPollSet ps, int num_threads)
+static void setup_standby_wait(ErtsPollSet *ps, int num_threads)
 {
     EnterCriticalSection(&(ps->standby_crit));
     ps->standby_wait_counter = num_threads;
@@ -571,7 +496,7 @@ static void setup_standby_wait(ErtsPollSet ps, int num_threads)
     LeaveCriticalSection(&(ps->standby_crit));
 }
 
-static void signal_standby(ErtsPollSet ps) 
+static void signal_standby(ErtsPollSet *ps)
 {
     EnterCriticalSection(&(ps->standby_crit));
     --(ps->standby_wait_counter);
@@ -585,7 +510,7 @@ static void signal_standby(ErtsPollSet ps)
     LeaveCriticalSection(&(ps->standby_crit));
 }
 
-static void wait_standby(ErtsPollSet ps)
+static void wait_standby(ErtsPollSet *ps)
 {
     WaitForSingleObject(ps->standby_wait_event,INFINITE);
 }
@@ -653,7 +578,7 @@ static void consistency_check(Waiter* w)
 
 #endif
 
-static void new_waiter(ErtsPollSet ps)
+static void new_waiter(ErtsPollSet *ps)
 {
     register Waiter* w;
     DWORD tid;			/* Id for thread. */
@@ -747,7 +672,7 @@ static void *break_waiter(void *param)
 static void *threaded_waiter(void *param)
 {
     register Waiter* w = (Waiter *) param;
-    ErtsPollSet ps = (ErtsPollSet) w->xdata;
+    ErtsPollSet *ps = (ErtsPollSet*) w->xdata;
 #ifdef HARD_POLL_DEBUG2
     HANDLE oold_fired[64];
     int num_oold_fired;
@@ -850,9 +775,9 @@ event_happened:
 	    ASSERT(i >= WAIT_OBJECT_0+1);
 	    i -= WAIT_OBJECT_0;
 	    ASSERT(i >= 1);
-	    w->active_events--;
 	    HARDDEBUGF(("i = %d, a,h,t = %d,%d,%d",i,
 			w->active_events, w->highwater, w->total_events));
+	    w->active_events--;
 #ifdef HARD_POLL_DEBUG2
 	    fired[num_fired++] = w->events[i];
 #endif
@@ -882,7 +807,7 @@ event_happened:
  * The actual adding and removing from pollset utilities 
  */
 
-static int set_driver_select(ErtsPollSet ps, HANDLE event, ErtsPollEvents mode)
+static int set_driver_select(ErtsPollSet *ps, HANDLE event, ErtsPollEvents mode)
 {
     int i;
     int best_waiter = -1;	/* The waiter with lowest number of events. */
@@ -972,13 +897,13 @@ static int set_driver_select(ErtsPollSet ps, HANDLE event, ErtsPollEvents mode)
 #endif
     erts_mtx_unlock(&w->mtx);
     START_WAITER(ps,w);
-    HARDDEBUGF(("add select %d %d %d %d",best_waiter,
+    HARDDEBUGF(("%d: add select %d %d %d %d", event, best_waiter,
 		w->active_events,w->highwater,w->total_events));
     return mode;
 }
 
 
-static int cancel_driver_select(ErtsPollSet ps, HANDLE event)
+static int cancel_driver_select(ErtsPollSet *ps, HANDLE event)
 {
     int i;
 
@@ -1033,7 +958,7 @@ static int cancel_driver_select(ErtsPollSet ps, HANDLE event)
  * Interface functions
  */
 
-void  erts_poll_interrupt(ErtsPollSet ps, int set /* bool */)
+void  erts_poll_interrupt(ErtsPollSet *ps, int set /* bool */)
 {
     HARDTRACEF(("In erts_poll_interrupt(%d)",set));
     if (!set)
@@ -1043,35 +968,23 @@ void  erts_poll_interrupt(ErtsPollSet ps, int set /* bool */)
     HARDTRACEF(("Out erts_poll_interrupt(%d)",set));
 }
 
-void erts_poll_interrupt_timed(ErtsPollSet ps,
-			       int set /* bool */,
-			       ErtsMonotonicTime timeout_time)
-{
-    HARDTRACEF(("In erts_poll_interrupt_timed(%d,%ld)",set,timeout_time));
-    if (!set)
-	reset_interrupt(ps);
-    else if (get_timeout_time(ps) > timeout_time)
-	set_interrupt(ps);
-    HARDTRACEF(("Out erts_poll_interrupt_timed"));
-}
-
 
 /*
  * Windows is special, there is actually only one event type, and
  * the only difference between ERTS_POLL_EV_IN and ERTS_POLL_EV_OUT
  * is which driver callback will eventually be called.
  */
-static ErtsPollEvents do_poll_control(ErtsPollSet ps,
-				      ErtsSysFdType fd,
-				      ErtsPollEvents pe,
-				      int on /* bool */)
+static ErtsPollEvents do_poll_control(ErtsPollSet *ps,
+                                      ErtsSysFdType fd,
+                                      ErtsPollOp op,
+                                      ErtsPollEvents pe)
 {
     HANDLE event = (HANDLE) fd;
     ErtsPollEvents mode;
     ErtsPollEvents result;
     ASSERT(event != INVALID_HANDLE_VALUE);
 
-    if (on) {
+    if (op != ERTS_POLL_OP_DEL) {
 	if (pe & ERTS_POLL_EV_IN || !(pe & ERTS_POLL_EV_OUT )) {
 	    mode = ERTS_POLL_EV_IN;
 	} else {
@@ -1084,51 +997,30 @@ static ErtsPollEvents do_poll_control(ErtsPollSet ps,
     return result;
 }
 
-ErtsPollEvents erts_poll_control(ErtsPollSet ps,
+ErtsPollEvents erts_poll_control(ErtsPollSet *ps,
 				 ErtsSysFdType fd,
+                                 ErtsPollOp op,
 				 ErtsPollEvents pe,
-				 int on,
 				 int* do_wake) /* In: Wake up polling thread */
 				               /* Out: Poller is woken */
 {
     ErtsPollEvents result;
-    HARDTRACEF(("In erts_poll_control(0x%08X, %u, %d)",(unsigned long) fd, (unsigned) pe, on));
+    HARDTRACEF(("In erts_poll_control(0x%08X, %s, %s)",
+                (unsigned long) fd, op2str(op), ev2str(pe)));
     ERTS_POLLSET_LOCK(ps);
-    result=do_poll_control(ps,fd,pe,on);
+    result=do_poll_control(ps, fd, op, pe);
     ERTS_POLLSET_UNLOCK(ps);
     *do_wake = 0; /* Never any need to wake polling threads on windows */
     HARDTRACEF(("Out erts_poll_control -> %u",(unsigned) result));
     return result;
 }
 
-void erts_poll_controlv(ErtsPollSet ps,
-			ErtsPollControlEntry pcev[],
-			int len)
-{
-    int i;
-    int hshur = 0;
-    int do_wake = 0;
-
-    HARDTRACEF(("In erts_poll_controlv(%d)",len));
-    ERTS_POLLSET_LOCK(ps);
-
-    for (i = 0; i < len; i++) {
-	pcev[i].events = do_poll_control(ps,
-					 pcev[i].fd,
-					 pcev[i].events,
-					 pcev[i].on);
-    }
-    ERTS_POLLSET_UNLOCK(ps);
-    HARDTRACEF(("Out erts_poll_controlv"));
-}
-
-int erts_poll_wait(ErtsPollSet ps,
+int erts_poll_wait(ErtsPollSet *ps,
 		   ErtsPollResFd pr[],
-		   int *len,
-		   ErtsMonotonicTime timeout_time)
+		   int *len)
 {
     int no_fds;
-    DWORD timeout;
+    DWORD timeout = INFINITE;
     EventData* ev;
     int res = 0;
     int num = 0;
@@ -1139,42 +1031,6 @@ int erts_poll_wait(ErtsPollSet ps,
     HARDTRACEF(("In erts_poll_wait"));
     ERTS_POLLSET_LOCK(ps);
 
-    if (!is_io_ready(ps) && ps->restore_events) {
-	HARDDEBUGF(("Restore events: %d",ps->num_waiters));
-	ps->restore_events = 0;
-	for (i = 0; i < ps->num_waiters; ++i) {
-	   Waiter* w = ps->waiter[i];
-	   erts_mtx_lock(&w->mtx);
-	   HARDDEBUGF(("Maybe reset %d %d %d %d",i,
-		       w->active_events,w->highwater,w->total_events));
-	   if (w->active_events < w->total_events) {
-	       erts_mtx_unlock(&w->mtx);
-	       STOP_WAITER(ps,w);
-	       HARDDEBUGF(("Need reset %d %d %d %d",i,
-			   w->active_events,w->highwater,w->total_events));
-	       erts_mtx_lock(&w->mtx);	       
-	       /* Need reset, just check that it doesn't have got more to tell */
-	       if (w->highwater != w->active_events) {
-		   HARDDEBUGF(("Oups!"));
-		   /* Oups, got signalled before we took the lock, can't reset */
-		   if(!is_io_ready(ps)) {
-		       erts_exit(ERTS_ERROR_EXIT,"Internal error: "
-				"Inconsistent io structures in erl_poll.\n");
-		   }
-		   START_WAITER(ps,w);
-		   erts_mtx_unlock(&w->mtx);
-		   ps->restore_events = 1; 
-		   continue;
-	       }
-	       w->active_events = w->highwater =  w->total_events;
-	       START_WAITER(ps,w);
-	       erts_mtx_unlock(&w->mtx);
-	   } else {
-	       erts_mtx_unlock(&w->mtx);
-	   }
-	}
-    }
-
     no_fds = *len;
 
 #ifdef ERTS_POLL_MAX_RES
@@ -1182,26 +1038,29 @@ int erts_poll_wait(ErtsPollSet ps,
 	no_fds = ERTS_POLL_MAX_RES;
 #endif
 
-    timeout = poll_wait_timeout(ps, timeout_time);
-
-    /*HARDDEBUGF(("timeout = %ld",(long) timeout));*/
+    ResetEvent(ps->event_io_ready);
+    /*
+     * Since we don't know the internals of ResetEvent() we issue
+     * a memory barrier as a safety precaution ensuring that
+     * the load of wakeup_state wont be reordered with stores made
+     * by ResetEvent().
+     */
+    ERTS_THR_MEMORY_BARRIER;
+    if (erts_atomic32_read_nob(&ps->wakeup_state) != ERTS_POLL_NOT_WOKEN)
+       timeout = (DWORD) 0;
 
-    if (timeout > 0 && !erts_atomic32_read_nob(&break_waiter_state)) {
+    if (!erts_atomic32_read_nob(&break_waiter_state)) {
 	HANDLE harr[2] = {ps->event_io_ready, break_happened_event};
 	int num_h = 2;
-        ERTS_MSACC_PUSH_STATE_M();
+        ERTS_MSACC_PUSH_STATE();
 
 	HARDDEBUGF(("Start waiting %d [%d]",num_h, (int) timeout));
 	ERTS_POLLSET_UNLOCK(ps);
-#ifdef ERTS_SMP
 	erts_thr_progress_prepare_wait(NULL);
-#endif
-        ERTS_MSACC_SET_STATE_CACHED_M(ERTS_MSACC_STATE_SLEEP);
+        ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_SLEEP);
 	WaitForMultipleObjects(num_h, harr, FALSE, timeout);
-#ifdef ERTS_SMP
 	erts_thr_progress_finalize_wait(NULL);
-#endif
-        ERTS_MSACC_POP_STATE_M();
+        ERTS_MSACC_POP_STATE();
 	ERTS_POLLSET_LOCK(ps);
 	HARDDEBUGF(("Stop waiting %d [%d]",num_h, (int) timeout));
 	woke_up(ps);
@@ -1234,7 +1093,7 @@ int erts_poll_wait(ErtsPollSet ps,
 
     reset_io_ready(ps);
 
-    n = ps->num_waiters;	
+    n = ps->num_waiters;
 
     for (i = 0; i < n; i++) {
 	Waiter* w = ps->waiter[i];
@@ -1260,11 +1119,10 @@ int erts_poll_wait(ErtsPollSet ps,
 		HARDDEBUGF(("To many FD's to report!"));
 		goto done;
 	    }
-	    HARDDEBUGF(("SET! Restore events"));
-	    ps->restore_events = 1;
 	    HARDDEBUGF(("Report %d,%d",i,j));
-	    pr[num].fd = (ErtsSysFdType) w->events[j];
-	    pr[num].events = w->evdata[j]->mode;
+	    ERTS_POLL_RES_SET_FD(&pr[num], w->events[j]);
+	    ERTS_POLL_RES_SET_EVTS(&pr[num], w->evdata[j]->mode);
+            remove_event_from_set(w, j);
 #ifdef HARD_POLL_DEBUG
 	    poll_debug_reported(w->events[j],w->highwater | (j << 16));
 	    poll_debug_reported(w->events[j],first | (last << 16));
@@ -1272,13 +1130,14 @@ int erts_poll_wait(ErtsPollSet ps,
 	    ++num;
 	}
 
+        w->total_events = w->highwater = w->active_events;
+
 #ifdef DEBUG
 	consistency_check(w);
 #endif
 	erts_mtx_unlock(&w->mtx);
     }
  done:
-    set_timeout_time(ps, ERTS_MONOTONIC_TIME_MAX);
     *len = num;
     ERTS_POLLSET_UNLOCK(ps);
     HARDTRACEF(("Out erts_poll_wait"));
@@ -1293,7 +1152,7 @@ int erts_poll_max_fds(void)
     return res;
 }
 
-void erts_poll_info(ErtsPollSet ps,
+void erts_poll_info(ErtsPollSet *ps,
 		    ErtsPollInfo *pip)
 {
     Uint size = 0;
@@ -1303,7 +1162,7 @@ void erts_poll_info(ErtsPollSet ps,
     HARDTRACEF(("In erts_poll_info"));
     ERTS_POLLSET_LOCK(ps);
 
-    size += sizeof(struct ErtsPollSet_);
+    size += sizeof(struct erts_pollset);
     size += sizeof(Waiter *) * ps->allocated_waiters;
     for (i = 0; i < ps->num_waiters; ++i) {
 	Waiter *w = ps->waiter[i];
@@ -1318,16 +1177,12 @@ void erts_poll_info(ErtsPollSet ps,
 
     pip->primary = "WaitForMultipleObjects"; 
 
-    pip->fallback = NULL;
-
     pip->kernel_poll = NULL;
 
     pip->memory_size = size;
 
     pip->poll_set_size = num_events;
 
-    pip->fallback_poll_set_size = 0;
-
     pip->lazy_updates = 0;
 
     pip->pending_updates = 0;
@@ -1335,6 +1190,8 @@ void erts_poll_info(ErtsPollSet ps,
     pip->batch_updates = 0;
 
     pip->concurrent_updates = 0;
+
+    pip->is_fallback = 0;
     ERTS_POLLSET_UNLOCK(ps);
 
     pip->max_fds = erts_poll_max_fds();
@@ -1342,10 +1199,10 @@ void erts_poll_info(ErtsPollSet ps,
 
 }
 
-ErtsPollSet erts_poll_create_pollset(void)
+ErtsPollSet *erts_poll_create_pollset(int no)
 {
-    ErtsPollSet ps = SEL_ALLOC(ERTS_ALC_T_POLLSET,
-			       sizeof(struct ErtsPollSet_));
+    ErtsPollSet *ps = SEL_ALLOC(ERTS_ALC_T_POLLSET,
+			       sizeof(struct erts_pollset));
     HARDTRACEF(("In erts_poll_create_pollset"));
 
     ps->num_waiters = 0;
@@ -1356,19 +1213,15 @@ ErtsPollSet erts_poll_create_pollset(void)
     ps->standby_wait_counter = 0;
     ps->event_io_ready = CreateManualEvent(FALSE);
     ps->standby_wait_event = CreateManualEvent(FALSE); 
-    ps->restore_events = 0;
 
     erts_atomic32_init_nob(&ps->wakeup_state, ERTS_POLL_NOT_WOKEN);
-#ifdef ERTS_SMP
-    erts_smp_mtx_init(&ps->mtx, "pollset", NIL, ERTS_LOCK_FLAGS_CATEGORY_IO);
-#endif
-    init_timeout_time(ps);
+    erts_mtx_init(&ps->mtx, "pollset", NIL, ERTS_LOCK_FLAGS_CATEGORY_IO);
 
     HARDTRACEF(("Out erts_poll_create_pollset"));
     return ps;
 }
 
-void erts_poll_destroy_pollset(ErtsPollSet ps)
+void erts_poll_destroy_pollset(ErtsPollSet *ps)
 {
     int i;
     HARDTRACEF(("In erts_poll_destroy_pollset"));
@@ -1391,9 +1244,7 @@ void erts_poll_destroy_pollset(ErtsPollSet ps)
     CloseHandle(ps->event_io_ready);
     CloseHandle(ps->standby_wait_event);
     ERTS_POLLSET_UNLOCK(ps);
-#ifdef ERTS_SMP
-    erts_smp_mtx_destroy(&ps->mtx);
-#endif
+    erts_mtx_destroy(&ps->mtx);
     SEL_FREE(ERTS_ALC_T_POLLSET, (void *) ps);
     HARDTRACEF(("Out erts_poll_destroy_pollset"));
 }
@@ -1401,14 +1252,16 @@ void erts_poll_destroy_pollset(ErtsPollSet ps)
 /*
  * Actually mostly initializes the friend module sys_interrupt...
  */
-void  erts_poll_init(void)
+void  erts_poll_init(int *concurrent_updates)
 {
-    erts_tid_t thread;
 
 #ifdef HARD_POLL_DEBUG
     poll_debug_init();
 #endif
 
+    if (concurrent_updates)
+        *concurrent_updates = 0;
+
     HARDTRACEF(("In erts_poll_init"));
     erts_sys_break_event = CreateManualEvent(FALSE);
 
@@ -1417,21 +1270,26 @@ void  erts_poll_init(void)
     break_happened_event = CreateManualEvent(FALSE);
     erts_atomic32_init_nob(&break_waiter_state, 0); 
 
+    HARDTRACEF(("Out erts_poll_init"));
+}
+
+void erts_poll_late_init(void)
+{
+    erts_tid_t thread;
     erts_thr_create(&thread, &break_waiter, NULL, NULL);
     ERTS_UNSET_BREAK_REQUESTED;
-    HARDTRACEF(("Out erts_poll_init"));
 }
 
 /*
  * Non windows friendly interface, not used when fd's are not continous
  */
-void  erts_poll_get_selected_events(ErtsPollSet ps,
+void  erts_poll_get_selected_events(ErtsPollSet *ps,
 				    ErtsPollEvents ev[],
 				    int len)
 {
     int i;
     HARDTRACEF(("In erts_poll_get_selected_events"));
     for (i = 0; i < len; ++i)
-	ev[i] = 0;
+	ev[i] = ERTS_POLL_EV_NONE;
     HARDTRACEF(("Out erts_poll_get_selected_events"));
 }
diff --git a/erts/emulator/sys/win32/erl_win_dyn_driver.h b/erts/emulator/sys/win32/erl_win_dyn_driver.h
index 6f28d513c2..0d1a6d4c87 100644
--- a/erts/emulator/sys/win32/erl_win_dyn_driver.h
+++ b/erts/emulator/sys/win32/erl_win_dyn_driver.h
@@ -40,7 +40,6 @@ WDD_TYPEDEF(int, driver_exit, (ErlDrvPort, int));
 WDD_TYPEDEF(int, driver_failure_eof, (ErlDrvPort));
 WDD_TYPEDEF(void, erl_drv_busy_msgq_limits, (ErlDrvPort, ErlDrvSizeT *, ErlDrvSizeT *));
 WDD_TYPEDEF(int, driver_select, (ErlDrvPort, ErlDrvEvent, int, int));
-WDD_TYPEDEF(int, driver_event, (ErlDrvPort, ErlDrvEvent,ErlDrvEventData));
 WDD_TYPEDEF(int, driver_output, (ErlDrvPort, char *, ErlDrvSizeT));
 WDD_TYPEDEF(int, driver_output2, (ErlDrvPort, char *, ErlDrvSizeT ,char *, ErlDrvSizeT));
 WDD_TYPEDEF(int, driver_output_binary, (ErlDrvPort, char *, ErlDrvSizeT, ErlDrvBinary*, ErlDrvSizeT, ErlDrvSizeT));
@@ -162,7 +161,7 @@ typedef struct {
     WDD_FTYPE(driver_failure_eof) *driver_failure_eof;
     WDD_FTYPE(erl_drv_busy_msgq_limits) *erl_drv_busy_msgq_limits;
     WDD_FTYPE(driver_select) *driver_select;
-    WDD_FTYPE(driver_event) *driver_event;
+    void *REMOVED_driver_event;
     WDD_FTYPE(driver_output) *driver_output;
     WDD_FTYPE(driver_output2) *driver_output2;
     WDD_FTYPE(driver_output_binary) *driver_output_binary;
@@ -276,7 +275,6 @@ extern TWinDynDriverCallbacks WinDynDriverCallbacks;
 #define driver_failure_eof (WinDynDriverCallbacks.driver_failure_eof)
 #define erl_drv_busy_msgq_limits (WinDynDriverCallbacks.erl_drv_busy_msgq_limits)
 #define driver_select (WinDynDriverCallbacks.driver_select)
-#define driver_event (WinDynDriverCallbacks.driver_event)
 #define driver_output (WinDynDriverCallbacks.driver_output)
 #define driver_output2 (WinDynDriverCallbacks.driver_output2)
 #define driver_output_binary (WinDynDriverCallbacks.driver_output_binary)
@@ -414,7 +412,7 @@ do {				                        \
 ((W).driver_failure_eof) = driver_failure_eof;		\
 ((W).erl_drv_busy_msgq_limits) = erl_drv_busy_msgq_limits;\
 ((W).driver_select) = driver_select;			\
-((W).driver_event) = driver_event;			\
+((W).REMOVED_driver_event) = NULL;			\
 ((W).driver_output) = driver_output;			\
 ((W).driver_output2) = driver_output2;			\
 ((W).driver_output_binary) = driver_output_binary;	\
diff --git a/erts/emulator/sys/win32/erl_win_sys.h b/erts/emulator/sys/win32/erl_win_sys.h
index 78005aada9..1f53452d17 100644
--- a/erts/emulator/sys/win32/erl_win_sys.h
+++ b/erts/emulator/sys/win32/erl_win_sys.h
@@ -311,10 +311,8 @@ typedef long ssize_t;
 #endif
 
 /* Threads */
-#ifdef USE_THREADS
 int init_async(int);
 int exit_async(void);
-#endif
 
 #define ERTS_HAVE_TRY_CATCH 1
 
diff --git a/erts/emulator/sys/win32/sys.c b/erts/emulator/sys/win32/sys.c
index 15c59109b1..0598a12351 100644
--- a/erts/emulator/sys/win32/sys.c
+++ b/erts/emulator/sys/win32/sys.c
@@ -80,11 +80,9 @@ static int application_type(const wchar_t* originalName, wchar_t fullPath[MAX_PA
 
 HANDLE erts_service_event;
 
-#ifdef ERTS_SMP
-static erts_smp_tsd_key_t win32_errstr_key;
-#endif
+static erts_tsd_key_t win32_errstr_key;
 
-static erts_smp_atomic_t pipe_creation_counter;
+static erts_atomic_t pipe_creation_counter;
 
 /* Results from application_type(_w) is one of */
 #define APPL_NONE 0
@@ -94,10 +92,8 @@ static erts_smp_atomic_t pipe_creation_counter;
 
 static int driver_write(long, HANDLE, byte*, int);
 static int create_file_thread(struct async_io* aio, int mode);
-#ifdef ERTS_SMP
 static void close_active_handle(DriverData *, HANDLE handle);
 static DWORD WINAPI threaded_handle_closer(LPVOID param);
-#endif
 static DWORD WINAPI threaded_reader(LPVOID param);
 static DWORD WINAPI threaded_writer(LPVOID param);
 static DWORD WINAPI threaded_exiter(LPVOID param);
@@ -136,7 +132,7 @@ static OSVERSIONINFO int_os_version;	/* Version information for Win32. */
     Disabled the use of CancelIoEx as its been seen to cause problem with some
     drivers. Not sure what to blame; faulty drivers or some form of invalid use.
 */
-#if defined(ERTS_SMP) && defined(USE_CANCELIOEX)
+#if defined(USE_CANCELIOEX)
 static BOOL (WINAPI *fpCancelIoEx)(HANDLE,LPOVERLAPPED);
 #endif
 
@@ -145,7 +141,7 @@ static BOOL (WINAPI *fpCancelIoEx)(HANDLE,LPOVERLAPPED);
    - call erl_start() to parse arguments and do other init
 */
 
-static erts_smp_atomic_t sys_misc_mem_sz;
+static erts_atomic_t sys_misc_mem_sz;
 
 HMODULE beam_module = NULL;
 
@@ -196,7 +192,7 @@ Uint
 erts_sys_misc_mem_sz(void)
 {
     Uint res = (Uint) erts_check_io_size();
-    res += (Uint) erts_smp_atomic_read_mb(&sys_misc_mem_sz);
+    res += (Uint) erts_atomic_read_mb(&sys_misc_mem_sz);
     return res;
 }
 
@@ -450,9 +446,7 @@ typedef struct async_io {
 				 * the console for Windows NT).
 				 */
   HANDLE fd;			/* Handle for file or pipe. */
-#ifdef ERTS_SMP
   int async_io_active;          /* if true, a close of the file will signal the event in ov */
-#endif
   OVERLAPPED ov;		/* Control structure for overlapped reading.
 				 * When overlapped reading is simulated with
 				 * a thread, the fields are used as follows:
@@ -665,7 +659,7 @@ new_driver_data(ErlDrvPort port_num, int packet_bytes, int wait_objs_required, i
     dp->inbuf = DRV_BUF_ALLOC(dp->inBufSize);
     if (dp->inbuf == NULL)
 	goto buf_alloc_error;
-    erts_smp_atomic_add_nob(&sys_misc_mem_sz, dp->inBufSize);
+    erts_atomic_add_nob(&sys_misc_mem_sz, dp->inBufSize);
     dp->outBufSize = 0;
     dp->outbuf = NULL;
     dp->port_num = port_num;
@@ -691,7 +685,6 @@ buf_alloc_error:
 static void
 release_driver_data(DriverData* dp)
 {
-#ifdef ERTS_SMP
 #ifdef USE_CANCELIOEX
     if (fpCancelIoEx != NULL) {
 	if (dp->in.thread == (HANDLE) -1 && dp->in.fd != INVALID_HANDLE_VALUE) {
@@ -734,18 +727,10 @@ release_driver_data(DriverData* dp)
 	    DEBUGF(("...done\n"));
 	}
     }
-#else
-	if (dp->in.thread == (HANDLE) -1 && dp->in.fd != INVALID_HANDLE_VALUE) {
-	     CancelIo(dp->in.fd); 
-	}
-	if (dp->out.thread == (HANDLE) -1 && dp->out.fd != INVALID_HANDLE_VALUE) {
-	    CancelIo(dp->out.fd); 
-	}
-#endif
 
     if (dp->inbuf != NULL) {
-	ASSERT(erts_smp_atomic_read_nob(&sys_misc_mem_sz) >= dp->inBufSize);
-	erts_smp_atomic_add_nob(&sys_misc_mem_sz, -1*dp->inBufSize);
+	ASSERT(erts_atomic_read_nob(&sys_misc_mem_sz) >= dp->inBufSize);
+	erts_atomic_add_nob(&sys_misc_mem_sz, -1*dp->inBufSize);
 	DRV_BUF_FREE(dp->inbuf);
 	dp->inBufSize = 0;
 	dp->inbuf = NULL;
@@ -753,8 +738,8 @@ release_driver_data(DriverData* dp)
     ASSERT(dp->inBufSize == 0);
 
     if (dp->outbuf != NULL) {
-	ASSERT(erts_smp_atomic_read_nob(&sys_misc_mem_sz) >= dp->outBufSize);
-	erts_smp_atomic_add_nob(&sys_misc_mem_sz, -1*dp->outBufSize);
+	ASSERT(erts_atomic_read_nob(&sys_misc_mem_sz) >= dp->outBufSize);
+	erts_atomic_add_nob(&sys_misc_mem_sz, -1*dp->outBufSize);
 	DRV_BUF_FREE(dp->outbuf);
 	dp->outBufSize = 0;
 	dp->outbuf = NULL;
@@ -777,7 +762,6 @@ release_driver_data(DriverData* dp)
     unrefer_driver_data(dp);
 }
 
-#ifdef ERTS_SMP
 
 struct handles_to_be_closed {
     HANDLE handles[MAXIMUM_WAIT_OBJECTS];
@@ -870,7 +854,6 @@ threaded_handle_closer(LPVOID param)
     DEBUGF(("threaded_handle_closer %p terminating\r\n", htbc));
     return 0;
 }
-#endif /* ERTS_SMP */
 
 /*
  * Stores input and output file descriptors in the DriverData structure,
@@ -946,9 +929,7 @@ init_async_io(DriverData *dp, AsyncIo* aio, int use_threads)
     aio->flushReplyEvent = NULL;
     aio->pendingError = 0;
     aio->bytesTransferred = 0;
-#ifdef ERTS_SMP
     aio->async_io_active = 0;
-#endif
     aio->ov.hEvent = CreateManualEvent(FALSE);
     if (aio->ov.hEvent == NULL)
 	return -1;
@@ -1029,9 +1010,7 @@ async_read_file(AsyncIo* aio, LPVOID buf, DWORD numToRead)
 	ResetEvent(aio->ov.hEvent);
 	SetEvent(aio->ioAllowed);
     } else {
-#ifdef ERTS_SMP
 	aio->async_io_active = 1; /* Will get 0 when the event actually happened */
-#endif
 	if (ReadFile(aio->fd, buf, numToRead,
 		     &aio->bytesTransferred, &aio->ov)) {
 	    DEBUGF(("async_read_file: ReadFile() suceeded: %d bytes\n",
@@ -1079,16 +1058,12 @@ async_write_file(AsyncIo* aio,		/* Pointer to async control block. */
 	ResetEvent(aio->ov.hEvent);
 	SetEvent(aio->ioAllowed);
     } else {
-#ifdef ERTS_SMP
 	aio->async_io_active = 1; /* Will get 0 when the event actually happened */
-#endif
 	if (WriteFile(aio->fd, buf, numToWrite,
 		      &aio->bytesTransferred, &aio->ov)) {
 	    DEBUGF(("async_write_file: WriteFile() suceeded: %d bytes\n",
 		    aio->bytesTransferred));
-#ifdef ERTS_SMP
 	    aio->async_io_active = 0; /* The event will not be signalled */
-#endif
 	    ResetEvent(aio->ov.hEvent);
 	    return TRUE;
 	} else {
@@ -1190,7 +1165,7 @@ static int
 spawn_init(void)
 {
     int i;
-#if defined(ERTS_SMP) && defined(USE_CANCELIOEX)
+#if defined(USE_CANCELIOEX)
     HMODULE module = GetModuleHandle("kernel32");
     fpCancelIoEx = (BOOL (WINAPI *)(HANDLE,LPOVERLAPPED))
 	((module != NULL) ? GetProcAddress(module,"CancelIoEx") : NULL);
@@ -1762,7 +1737,7 @@ static int create_pipe(HANDLE *phRead, HANDLE *phWrite, BOOL inheritRead, BOOL o
      * Otherwise, create named pipes.
      */
 
-    calls = (UWord) erts_smp_atomic_inc_read_nob(&pipe_creation_counter);
+    calls = (UWord) erts_atomic_inc_read_nob(&pipe_creation_counter);
     erts_snprintf(pipe_name, sizeof(pipe_name),
 		  "\\\\.\\pipe\\erlang44_%d_%bpu", getpid(), calls);
 
@@ -2447,7 +2422,7 @@ output(ErlDrvData drv_data, char* buf, ErlDrvSizeT len)
     }
 
     dp->outBufSize = pb+len;
-    erts_smp_atomic_add_nob(&sys_misc_mem_sz, dp->outBufSize);
+    erts_atomic_add_nob(&sys_misc_mem_sz, dp->outBufSize);
 
     /*
      * Store header bytes (if any).
@@ -2476,8 +2451,8 @@ output(ErlDrvData drv_data, char* buf, ErlDrvSizeT len)
     } else {
 	dp->out.ov.Offset += pb+len; /* For vanilla driver. */
 	/* XXX OffsetHigh should be changed too. */
-	ASSERT(erts_smp_atomic_read_nob(&sys_misc_mem_sz) >= dp->outBufSize);
-	erts_smp_atomic_add_nob(&sys_misc_mem_sz, -1*dp->outBufSize);
+	ASSERT(erts_atomic_read_nob(&sys_misc_mem_sz) >= dp->outBufSize);
+	erts_atomic_add_nob(&sys_misc_mem_sz, -1*dp->outBufSize);
 	DRV_BUF_FREE(dp->outbuf);
 	dp->outBufSize = 0;
 	dp->outbuf = NULL;
@@ -2511,11 +2486,9 @@ ready_input(ErlDrvData drv_data, ErlDrvEvent ready_event)
     int pb;
 
     pb = dp->packet_bytes;
-#ifdef ERTS_SMP
     if(dp->in.thread == (HANDLE) -1) {
 	dp->in.async_io_active = 0;
     }
-#endif
     DEBUGF(("ready_input: dp %p, event 0x%x\n", dp, ready_event));
 
     /*
@@ -2590,8 +2563,8 @@ ready_input(ErlDrvData drv_data, ErlDrvEvent ready_event)
 			    error = ERROR_NOT_ENOUGH_MEMORY;
 			    break; /* Break out of loop into error handler. */
 			}
-			ASSERT(erts_smp_atomic_read_nob(&sys_misc_mem_sz) >= dp->inBufSize);
-			erts_smp_atomic_add_nob(&sys_misc_mem_sz,
+			ASSERT(erts_atomic_read_nob(&sys_misc_mem_sz) >= dp->inBufSize);
+			erts_atomic_add_nob(&sys_misc_mem_sz,
 						dp->totalNeeded - dp->inBufSize);
 			dp->inBufSize = dp->totalNeeded;
 			dp->inbuf = new_buf;
@@ -2680,11 +2653,9 @@ ready_output(ErlDrvData drv_data, ErlDrvEvent ready_event)
     DriverData *dp = (DriverData *) drv_data;
     int error;
 
-#ifdef ERTS_SMP
     if(dp->out.thread == (HANDLE) -1) {
 	dp->out.async_io_active = 0;
     }
-#endif
     DEBUGF(("ready_output(%p, 0x%x)\n", drv_data, ready_event));
     set_busy_port(dp->port_num, 0);
     if (!(dp->outbuf)) {
@@ -2692,8 +2663,8 @@ ready_output(ErlDrvData drv_data, ErlDrvEvent ready_event)
 	   write... */
 	return;
     }
-    ASSERT(erts_smp_atomic_read_nob(&sys_misc_mem_sz) >= dp->outBufSize);
-    erts_smp_atomic_add_nob(&sys_misc_mem_sz, -1*dp->outBufSize);
+    ASSERT(erts_atomic_read_nob(&sys_misc_mem_sz) >= dp->outBufSize);
+    erts_atomic_add_nob(&sys_misc_mem_sz, -1*dp->outBufSize);
     DRV_BUF_FREE(dp->outbuf);
     dp->outBufSize = 0;
     dp->outbuf = NULL;
@@ -2743,7 +2714,6 @@ sys_init_io(void)
     max_files = 2*erts_ptab_max(&erts_port);
 }
 
-#ifdef ERTS_SMP
 void
 erts_sys_main_thread(void)
 {
@@ -2756,7 +2726,6 @@ erts_sys_main_thread(void)
 	WaitForSingleObject(dummy, INFINITE);
     }
 }
-#endif
 
 void erts_sys_alloc_init(void)
 {
@@ -2843,7 +2812,7 @@ Preload* sys_preloaded(void)
 			   (num_preloaded+1)*sizeof(Preload));
     res_name = erts_alloc(ERTS_ALC_T_PRELOADED,
 			  (num_preloaded+1)*sizeof(unsigned));
-    erts_smp_atomic_add_nob(&sys_misc_mem_sz,
+    erts_atomic_add_nob(&sys_misc_mem_sz,
 			    (num_preloaded+1)*sizeof(Preload)
 			    + (num_preloaded+1)*sizeof(unsigned));
     for (i = 0; i < num_preloaded; i++) {
@@ -2856,7 +2825,7 @@ Preload* sys_preloaded(void)
 	n = GETWORD(data);
 	data += 2;
 	preloaded[i].name = erts_alloc(ERTS_ALC_T_PRELOADED, n+1);
-	erts_smp_atomic_add_nob(&sys_misc_mem_sz, n+1);
+	erts_atomic_add_nob(&sys_misc_mem_sz, n+1);
 	sys_memcpy(preloaded[i].name, data, n);
 	preloaded[i].name[n] = '\0';
 	data += n;
@@ -2938,11 +2907,7 @@ sys_get_key(int fd)
 
 char* win32_errorstr(int error)
 {
-#ifdef SMP
-  LPTSTR lpBufPtr = erts_smp_tsd_get(win32_errstr_key);
-#else
-  static LPTSTR lpBufPtr = NULL;
-#endif
+  LPTSTR lpBufPtr = erts_tsd_get(win32_errstr_key);
   if (lpBufPtr) {
       LocalFree(lpBufPtr);
   }
@@ -2956,9 +2921,7 @@ char* win32_errorstr(int error)
 		0,
 		NULL);
   SetLastError(error);
-#ifdef ERTS_SMP
-  erts_smp_tsd_set(win32_errstr_key,lpBufPtr);
-#endif
+  erts_tsd_set(win32_errstr_key,lpBufPtr);
   return lpBufPtr;
 }
 
@@ -3131,7 +3094,6 @@ check_supported_os_version(void)
 #endif
 }
 
-#ifdef USE_THREADS
 
 typedef struct {
     int sched_bind_data;
@@ -3176,19 +3138,15 @@ thr_create_prepare_child(void *vtcdp)
     erts_sched_bind_atthrcreate_child(tcdp->sched_bind_data);
 }
 
-#endif /* USE_THREADS */
 
 void
 erts_sys_pre_init(void)
 {
-#ifdef USE_THREADS
     erts_thr_init_data_t eid = ERTS_THR_INIT_DATA_DEF_INITER;
-#endif
     int_os_version.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
     GetVersionEx(&int_os_version);
     check_supported_os_version();
 
-#ifdef USE_THREADS
     eid.thread_create_child_func = thr_create_prepare_child;
     /* Before creation in parent */
     eid.thread_create_prepare_func = thr_create_prepare;
@@ -3209,11 +3167,10 @@ erts_sys_pre_init(void)
     erts_lc_init();
 #endif
 
-#endif /* USE_THREADS */
 
     erts_init_sys_time_sup();
 
-    erts_smp_atomic_init_nob(&sys_misc_mem_sz, 0);
+    erts_atomic_init_nob(&sys_misc_mem_sz, 0);
 }
 
 void noinherit_std_handle(DWORD type)
@@ -3233,11 +3190,9 @@ void erl_sys_init(void)
     noinherit_std_handle(STD_INPUT_HANDLE);
     noinherit_std_handle(STD_ERROR_HANDLE);
 
-#ifdef ERTS_SMP
-    erts_smp_tsd_key_create(&win32_errstr_key,"win32_errstr_key");
+    erts_tsd_key_create(&win32_errstr_key,"win32_errstr_key");
     InitializeCriticalSection(&htbc_lock);
-#endif
-    erts_smp_atomic_init_nob(&pipe_creation_counter,0);
+    erts_atomic_init_nob(&pipe_creation_counter,0);
     /*
      * Test if we have named pipes or not.
      */
@@ -3280,42 +3235,16 @@ void erl_sys_init(void)
 	SetStdHandle(STD_ERROR_HANDLE, GetStdHandle(STD_OUTPUT_HANDLE));
     }
     erts_sys_init_float();
-    erts_init_check_io();
 
     /* Suppress windows error message popups */
     SetErrorMode(SetErrorMode(0) |
 		 SEM_FAILCRITICALERRORS | SEM_NOOPENFILEERRORBOX); 
 }
+void erts_poll_late_init(void);
 
 void
 erl_sys_late_init(void)
 {
     /* do nothing */
+    erts_poll_late_init();
 }
-
-void
-erts_sys_schedule_interrupt(int set)
-{
-    erts_check_io_interrupt(set);
-}
-
-#ifdef ERTS_SMP
-void
-erts_sys_schedule_interrupt_timed(int set, ErtsMonotonicTime timeout_time)
-{
-    erts_check_io_interrupt_timed(set, timeout_time);
-}
-#endif
-
-/*
- * Called from schedule() when it runs out of runnable processes,
- * or when Erlang code has performed INPUT_REDUCTIONS reduction
- * steps. runnable == 0 iff there are no runnable Erlang processes.
- */
-void
-erl_sys_schedule(int runnable)
-{
-    erts_check_io(!runnable);
-    ERTS_SMP_LC_ASSERT(!erts_thr_progress_is_blocking());
-}
-
diff --git a/erts/emulator/sys/win32/sys_env.c b/erts/emulator/sys/win32/sys_env.c
index 8fcee1cbb6..5792816267 100644
--- a/erts/emulator/sys/win32/sys_env.c
+++ b/erts/emulator/sys/win32/sys_env.c
@@ -32,12 +32,12 @@ static WCHAR **env_to_arg(WCHAR *env);
 static WCHAR **find_arg(WCHAR **arg, WCHAR *str);

 static int compare(const void *a, const void *b);

 

-static erts_smp_rwmtx_t environ_rwmtx;

+static erts_rwmtx_t environ_rwmtx;
 

 void

 erts_sys_env_init(void)

 {

-    erts_smp_rwmtx_init(&environ_rwmtx, "environ", NIL,

+    erts_rwmtx_init(&environ_rwmtx, "environ", NIL,
         ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);

 }

 

@@ -45,10 +45,10 @@ int
 erts_sys_putenv_raw(char *key, char *value)

 {

     int res;

-    erts_smp_rwmtx_rwlock(&environ_rwmtx);

+    erts_rwmtx_rwlock(&environ_rwmtx);
     res = (SetEnvironmentVariable((LPCTSTR) key,

 				  (LPCTSTR) value) ? 0 : 1);

-    erts_smp_rwmtx_rwunlock(&environ_rwmtx);

+    erts_rwmtx_rwunlock(&environ_rwmtx);
     return res;

 }

 

@@ -58,10 +58,10 @@ erts_sys_putenv(char *key, char *value)
     int res;

     WCHAR *wkey = (WCHAR *) key;

     WCHAR *wvalue = (WCHAR *) value;

-    erts_smp_rwmtx_rwlock(&environ_rwmtx);

+    erts_rwmtx_rwlock(&environ_rwmtx);
     res = (SetEnvironmentVariableW(wkey,

 				   wvalue) ? 0 : 1);

-    erts_smp_rwmtx_rwunlock(&environ_rwmtx);

+    erts_rwmtx_rwunlock(&environ_rwmtx);
     return res;

 }

 

@@ -76,12 +76,12 @@ erts_sys_getenv(char *key, char *value, size_t *size)
     DWORD wsize = *size / (sizeof(WCHAR) / sizeof(char));

 

     SetLastError(0);

-    erts_smp_rwmtx_rlock(&environ_rwmtx);

+    erts_rwmtx_rlock(&environ_rwmtx);
     new_size = GetEnvironmentVariableW(wkey,

 				       wvalue,

 				      (DWORD) wsize);

     res = !new_size && GetLastError() == ERROR_ENVVAR_NOT_FOUND ? -1 : 0;

-    erts_smp_rwmtx_runlock(&environ_rwmtx);

+    erts_rwmtx_runlock(&environ_rwmtx);
     if (res < 0)

 	return res;

     res = new_size > wsize ? 1 : 0;

@@ -111,22 +111,22 @@ int
 erts_sys_getenv_raw(char *key, char *value, size_t *size)

 {

     int res;

-    erts_smp_rwmtx_rlock(&environ_rwmtx);

+    erts_rwmtx_rlock(&environ_rwmtx);
     res = erts_sys_getenv__(key, value, size);

-    erts_smp_rwmtx_runlock(&environ_rwmtx);

+    erts_rwmtx_runlock(&environ_rwmtx);
     return res;

 }

 

 void init_getenv_state(GETENV_STATE *state)

 {

-    erts_smp_rwmtx_rlock(&environ_rwmtx);

+    erts_rwmtx_rlock(&environ_rwmtx);
     state->environment_strings = GetEnvironmentStringsW();

     state->next_string = state->environment_strings;

 }

 

 char *getenv_string(GETENV_STATE *state)

 {

-    ERTS_SMP_LC_ASSERT(erts_smp_lc_rwmtx_is_rlocked(&environ_rwmtx));

+    ERTS_LC_ASSERT(erts_lc_rwmtx_is_rlocked(&environ_rwmtx));
     if (state->next_string[0] == L'\0') {

 	return NULL;

     } else {

@@ -140,7 +140,7 @@ void fini_getenv_state(GETENV_STATE *state)
 {

     FreeEnvironmentStringsW(state->environment_strings);

     state->environment_strings = state->next_string = NULL;

-    erts_smp_rwmtx_runlock(&environ_rwmtx);

+    erts_rwmtx_runlock(&environ_rwmtx);
 }

 

 int erts_sys_unsetenv(char *key)

@@ -149,7 +149,7 @@ int erts_sys_unsetenv(char *key)
     WCHAR *wkey = (WCHAR *) key;

 

     SetLastError(0);

-    erts_smp_rwmtx_rlock(&environ_rwmtx);

+    erts_rwmtx_rlock(&environ_rwmtx);
     GetEnvironmentVariableW(wkey,

                             NULL,

                             0);

@@ -157,7 +157,7 @@ int erts_sys_unsetenv(char *key)
         res = (SetEnvironmentVariableW(wkey,

                                        NULL) ? 0 : 1);

     }

-    erts_smp_rwmtx_runlock(&environ_rwmtx);

+    erts_rwmtx_runlock(&environ_rwmtx);
     return res;

 }

 

@@ -171,12 +171,12 @@ win_build_environment(char* new_env)
 

 	tmp_new = (WCHAR *) new_env;

 	

-	erts_smp_rwmtx_rlock(&environ_rwmtx);

+	erts_rwmtx_rlock(&environ_rwmtx);
 	tmp = GetEnvironmentStringsW();

 	merged = merge_environment(tmp, tmp_new);

 

 	FreeEnvironmentStringsW(tmp);

-	erts_smp_rwmtx_runlock(&environ_rwmtx);

+	erts_rwmtx_runlock(&environ_rwmtx);
 	return (char *) merged;

     }

 }

diff --git a/erts/emulator/sys/win32/sys_interrupt.c b/erts/emulator/sys/win32/sys_interrupt.c
index df838960eb..02aa50500f 100644
--- a/erts/emulator/sys/win32/sys_interrupt.c
+++ b/erts/emulator/sys/win32/sys_interrupt.c
@@ -35,17 +35,11 @@
 #  define WIN_SYS_INLINE __forceinline
 #endif
 
-#ifdef ERTS_SMP
-erts_smp_atomic32_t erts_break_requested;
+erts_atomic32_t erts_break_requested;
 #define ERTS_SET_BREAK_REQUESTED \
-  erts_smp_atomic32_set_nob(&erts_break_requested, (erts_aint32_t) 1)
+  erts_atomic32_set_nob(&erts_break_requested, (erts_aint32_t) 1)
 #define ERTS_UNSET_BREAK_REQUESTED \
-  erts_smp_atomic32_set_nob(&erts_break_requested, (erts_aint32_t) 0)
-#else
-volatile int erts_break_requested = 0;
-#define ERTS_SET_BREAK_REQUESTED (erts_break_requested = 1)
-#define ERTS_UNSET_BREAK_REQUESTED (erts_break_requested = 0)
-#endif
+  erts_atomic32_set_nob(&erts_break_requested, (erts_aint32_t) 0)
 
 extern int nohup;
 HANDLE erts_sys_break_event = NULL;
@@ -57,14 +51,14 @@ void erts_do_break_handling(void)
      * therefore, make sure that all threads but this one are blocked before
      * proceeding!
      */
-    erts_smp_thr_progress_block();
+    erts_thr_progress_block();
     /* call the break handling function, reset the flag */
     do_break();
 
     ResetEvent(erts_sys_break_event);
     ERTS_UNSET_BREAK_REQUESTED;
 
-    erts_smp_thr_progress_unblock();
+    erts_thr_progress_unblock();
 }
 
 
diff --git a/erts/emulator/sys/win32/sys_time.c b/erts/emulator/sys/win32/sys_time.c
index 88131aaa6a..25c2ad385c 100644
--- a/erts/emulator/sys/win32/sys_time.c
+++ b/erts/emulator/sys/win32/sys_time.c
@@ -95,7 +95,7 @@ struct sys_time_internal_state_read_mostly__ {
 };
 
 struct sys_time_internal_state_write_freq__ {
-    erts_smp_mtx_t mtime_mtx;
+    erts_mtx_t mtime_mtx;
     ULONGLONG wrap;
     ULONGLONG last_tick_count;
 };
@@ -187,8 +187,6 @@ os_monotonic_time_gtc32(void)
 {
     ErtsMonotonicTime mtime;
     Uint32 ticks = (Uint32) GetTickCount();
-    ERTS_CHK_EXTEND_OS_MONOTONIC_TIME(&internal_state.wr.m.os_mtime_xtnd,
-				      ticks);
     mtime = ERTS_EXTEND_OS_MONOTONIC_TIME(&internal_state.wr.m.os_mtime_xtnd,
 					  ticks);
     mtime <<= ERTS_GET_TICK_COUNT_TIME_UNIT_SHIFT;
@@ -205,8 +203,6 @@ os_times_gtc32(ErtsMonotonicTime *mtimep, ErtsSystemTime *stimep)
     ticks = (Uint32) GetTickCount();
     GetSystemTime(&st);
 
-    ERTS_CHK_EXTEND_OS_MONOTONIC_TIME(&internal_state.wr.m.os_mtime_xtnd,
-				      ticks);
     mtime = ERTS_EXTEND_OS_MONOTONIC_TIME(&internal_state.wr.m.os_mtime_xtnd,
 					  ticks);
     mtime <<= ERTS_GET_TICK_COUNT_TIME_UNIT_SHIFT;
@@ -265,8 +261,6 @@ sys_hrtime_gtc32(void)
 {
     ErtsSysHrTime time;
     Uint32 ticks = (Uint32) GetTickCount();
-    ERTS_CHK_EXTEND_OS_MONOTONIC_TIME(&internal_state.wr.m.os_mtime_xtnd,
-				      tick_count);
     time = (ErtsSysHrTime) ERTS_EXTEND_OS_MONOTONIC_TIME(&internal_state.wr.m.os_mtime_xtnd,
 							 ticks);
     time *= (ErtsSysHrTime) (1000 * 1000);
@@ -300,7 +294,7 @@ sys_init_time(ErtsSysInitTimeResult *init_resp)
     module = GetModuleHandle(kernel_dll_name);
     if (!module) {
     get_tick_count:
-        erts_smp_mtx_init(&internal_state.w.f.mtime_mtx, "os_monotonic_time", NIL,
+        erts_mtx_init(&internal_state.w.f.mtime_mtx, "os_monotonic_time", NIL,
             ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
 	internal_state.w.f.wrap = 0;
 	internal_state.w.f.last_tick_count = 0;
diff --git a/erts/emulator/test/Makefile b/erts/emulator/test/Makefile
index b17170c8b8..bf00de2204 100644
--- a/erts/emulator/test/Makefile
+++ b/erts/emulator/test/Makefile
@@ -57,6 +57,7 @@ MODULES= \
 	dirty_nif_SUITE \
 	distribution_SUITE \
 	driver_SUITE \
+	dump_SUITE \
 	efile_SUITE \
 	erts_debug_SUITE \
 	estone_SUITE \
diff --git a/erts/emulator/test/alloc_SUITE.erl b/erts/emulator/test/alloc_SUITE.erl
index 3a721095e2..5e5cd6f578 100644
--- a/erts/emulator/test/alloc_SUITE.erl
+++ b/erts/emulator/test/alloc_SUITE.erl
@@ -65,12 +65,7 @@ mseg_clear_cache(Cfg) -> drv_case(Cfg).
 cpool(Cfg) -> drv_case(Cfg).
 
 migration(Cfg) ->
-    case erlang:system_info(smp_support) of
-	true ->
-	    drv_case(Cfg, concurrent, "+MZe true");
-	false ->
-	    {skipped, "No smp"}
-    end.
+    drv_case(Cfg, concurrent, "+MZe true").
 
 erts_mmap(Config) when is_list(Config) ->
     case {os:type(), mmsc_flags()} of
@@ -94,10 +89,11 @@ mmsc_flags() ->
 mmsc_flags(Env) ->
     case os:getenv(Env) of
 	false -> false;
-	V -> case string:str(V, "+MMsc") of
-		 0 -> false;
-		 P -> Env ++ "=" ++ string:substr(V, P)
-	     end
+	V ->
+            case string:find(V, "+MMsc") of
+                nomatch -> false;
+                SubStr -> Env ++ "=" ++ SubStr
+            end
     end.
 
 erts_mmap_do(Config, SCO, SCRPM, SCRFSD) ->
diff --git a/erts/emulator/test/beam_SUITE.erl b/erts/emulator/test/beam_SUITE.erl
index 6a54fa87e0..bdf8f6c34e 100644
--- a/erts/emulator/test/beam_SUITE.erl
+++ b/erts/emulator/test/beam_SUITE.erl
@@ -113,20 +113,41 @@ packed_registers(Config) when is_list(Config) ->
 		   VarName = list_to_atom("M"++integer_to_list(V)),
 		   merl:var(VarName)
 	       end || V <- Seq],
+    MoreNewVars = [begin
+                       VarName = list_to_atom("MM"++integer_to_list(V)),
+                       merl:var(VarName)
+                   end || V <- Seq],
+    TupleEls = [?Q("id(_@Value@)") || {_,Value} <- S0],
     S = [?Q("_@Var = id(_@Value@)") || {Var,Value} <- S0],
     Code = ?Q(["-module('@Mod@').\n"
 	       "-export([f/0]).\n"
 	       "f() ->\n"
+               "Tuple = id({_@TupleEls}),\n"
+               "{_@MoreNewVars} = Tuple,\n"
 	       "_@S,\n"
 	       "_ = id(0),\n"
 	       "L = [_@Vars],\n"
 	       "_ = id(1),\n"
 	       "[_@NewVars] = L,\n"		%Test get_list/3.
 	       "_ = id(2),\n"
-	       "id([_@Vars,_@NewVars]).\n"
+	       "id([_@Vars,_@NewVars,_@MoreNewVars]).\n"
 	       "id(I) -> I.\n"]),
     merl:compile_and_load(Code),
-    CombinedSeq = Seq ++ Seq,
+
+    %% Optionally print the generated code.
+    PrintCode = false,                          %Change to true to print code.
+
+    case PrintCode of
+        false ->
+            ok;
+        true ->
+            merl:print(Code),
+            erts_debug:df(Mod),
+            {ok,Dis} = file:read_file(atom_to_list(Mod)++".dis"),
+            io:put_chars(Dis)
+    end,
+
+    CombinedSeq = Seq ++ Seq ++ Seq,
     CombinedSeq = Mod:f(),
 
     %% Clean up.
diff --git a/erts/emulator/test/bif_SUITE.erl b/erts/emulator/test/bif_SUITE.erl
index 04b7f2de15..e1b42e5d85 100644
--- a/erts/emulator/test/bif_SUITE.erl
+++ b/erts/emulator/test/bif_SUITE.erl
@@ -731,10 +731,12 @@ erlang_halt(Config) when is_list(Config) ->
                                  [broken_halt, "Validate correct crash dump"]),
     {ok,_} = wait_until_stable_size(CrashDump,-1),
     {ok, Bin} = file:read_file(CrashDump),
-    case {string:str(binary_to_list(Bin),"\n=end\n"),
-          string:str(binary_to_list(Bin),"\r\n=end\r\n")} of
-        {0,0} -> ct:fail("Could not find end marker in crash dump");
-        _ -> ok
+    case {string:find(Bin, <<"\n=end\n">>),
+          string:find(Bin, <<"\r\n=end\r\n">>)} of
+        {nomatch,nomatch} ->
+            ct:fail("Could not find end marker in crash dump");
+        {_,_} ->
+            ok
     end.
 
 wait_until_stable_size(_File,-10) ->
@@ -779,14 +781,20 @@ is_builtin(_Config) ->
 		       {F,A} <- M:module_info(exports)],
     Exp = ordsets:from_list(Exp0),
 
-    %% erlang:apply/3 is considered to be built-in, but is not
-    %% implemented as other BIFs.
+    %% Built-ins implemented as special instructions.
+    Instructions = [{erlang,apply,2},{erlang,apply,3},{erlang,yield,0}],
 
-    Builtins0 = [{erlang,apply,3}|erlang:system_info(snifs)],
+    Builtins0 = Instructions ++ erlang:system_info(snifs),
     Builtins = ordsets:from_list(Builtins0),
-    NotBuiltin = ordsets:subtract(Exp, Builtins),
-    _ = [true = erlang:is_builtin(M, F, A) || {M,F,A} <- Builtins],
-    _ = [false = erlang:is_builtin(M, F, A) || {M,F,A} <- NotBuiltin],
+
+    Fakes = [{M,F,42} || {M,F,_} <- Instructions],
+    All = ordsets:from_list(Fakes ++ Exp),
+    NotBuiltin = ordsets:subtract(All, Builtins),
+
+    _ = [{true,_} = {erlang:is_builtin(M, F, A),MFA} ||
+            {M,F,A}=MFA <- Builtins],
+    _ = [{false,_} = {erlang:is_builtin(M, F, A),MFA} ||
+            {M,F,A}=MFA <- NotBuiltin],
 
     ok.
 
diff --git a/erts/emulator/test/big_SUITE.erl b/erts/emulator/test/big_SUITE.erl
index c308760211..5939d024ae 100644
--- a/erts/emulator/test/big_SUITE.erl
+++ b/erts/emulator/test/big_SUITE.erl
@@ -339,6 +339,13 @@ system_limit(Config) when is_list(Config) ->
     {'EXIT',{system_limit,_}} = (catch apply(erlang, id('bsl'), [Maxbig,2])),
     {'EXIT',{system_limit,_}} = (catch id(1) bsl (1 bsl 45)),
     {'EXIT',{system_limit,_}} = (catch id(1) bsl (1 bsl 69)),
+
+    %% There should be no system_limit exception when shifting a zero.
+    0 = id(0) bsl (1 bsl 128),
+    0 = id(0) bsr -(1 bsl 128),
+    Erlang = id(erlang),
+    0 = Erlang:'bsl'(id(0), 1 bsl 128),
+    0 = Erlang:'bsr'(id(0), -(1 bsl 128)),
     ok.
 
 maxbig() ->
diff --git a/erts/emulator/test/binary_SUITE.erl b/erts/emulator/test/binary_SUITE.erl
index 61536bacd7..4bc1838139 100644
--- a/erts/emulator/test/binary_SUITE.erl
+++ b/erts/emulator/test/binary_SUITE.erl
@@ -48,6 +48,7 @@
 	 bad_list_to_binary/1, bad_binary_to_list/1,
 	 t_split_binary/1, bad_split/1,
 	 terms/1, terms_float/1, float_middle_endian/1,
+         b2t_used_big/1,
 	 external_size/1, t_iolist_size/1,
 	 t_hash/1,
 	 bad_size/1,
@@ -57,7 +58,9 @@
 	 otp_5484/1,otp_5933/1,
 	 ordering/1,unaligned_order/1,gc_test/1,
 	 bit_sized_binary_sizes/1,
-	 otp_6817/1,deep/1,obsolete_funs/1,robustness/1,otp_8117/1,
+	 otp_6817/1,deep/1,
+         term2bin_tuple_fallbacks/1,
+         robustness/1,otp_8117/1,
 	 otp_8180/1, trapping/1, large/1,
 	 error_after_yield/1, cmp_old_impl/1]).
 
@@ -72,12 +75,14 @@ all() ->
      t_split_binary, bad_split,
      bad_list_to_binary, bad_binary_to_list, terms,
      terms_float, float_middle_endian, external_size, t_iolist_size,
+     b2t_used_big,
      bad_binary_to_term_2, safe_binary_to_term2,
      bad_binary_to_term, bad_terms, t_hash, bad_size,
      bad_term_to_binary, more_bad_terms, otp_5484, otp_5933,
      ordering, unaligned_order, gc_test,
      bit_sized_binary_sizes, otp_6817, otp_8117, deep,
-     obsolete_funs, robustness, otp_8180, trapping, large,
+     term2bin_tuple_fallbacks,
+     robustness, otp_8180, trapping, large,
      error_after_yield, cmp_old_impl].
 
 groups() -> 
@@ -425,40 +430,77 @@ bad_term_to_binary(Config) when is_list(Config) ->
 
 terms(Config) when is_list(Config) ->
     TestFun = fun(Term) ->
-		      try
-			  S = io_lib:format("~p", [Term]),
-			  io:put_chars(S)
-		      catch
-			  error:badarg ->
-			      io:put_chars("bit sized binary")
-		      end,
+                      S = io_lib:format("~p", [Term]),
+                      io:put_chars(S),
 		      Bin = term_to_binary(Term),
 		      case erlang:external_size(Bin) of
 			  Sz when is_integer(Sz), size(Bin) =< Sz ->
 			      ok
 		      end,
-              Bin1 = term_to_binary(Term, [{minor_version, 1}]),
-              case erlang:external_size(Bin1, [{minor_version, 1}]) of
-              Sz1 when is_integer(Sz1), size(Bin1) =< Sz1 ->
-                  ok
-              end,
+                      Bin1 = term_to_binary(Term, [{minor_version, 1}]),
+                      case erlang:external_size(Bin1, [{minor_version, 1}]) of
+                          Sz1 when is_integer(Sz1), size(Bin1) =< Sz1 ->
+                              ok
+                      end,
 		      Term = binary_to_term_stress(Bin),
 		      Term = binary_to_term_stress(Bin, [safe]),
-		      Unaligned = make_unaligned_sub_binary(Bin),
-		      Term = binary_to_term_stress(Unaligned),
-		      Term = binary_to_term_stress(Unaligned, []),
-		      Term = binary_to_term_stress(Bin, [safe]),
+                      Bin_sz = byte_size(Bin),
+		      {Term,Bin_sz} = binary_to_term_stress(Bin, [used]),
+
+                      BinE = <<Bin/binary, 1, 2, 3>>,
+		      {Term,Bin_sz} = binary_to_term_stress(BinE, [used]),
+
+		      BinU = make_unaligned_sub_binary(Bin),
+		      Term = binary_to_term_stress(BinU),
+		      Term = binary_to_term_stress(BinU, []),
+		      Term = binary_to_term_stress(BinU, [safe]),
+		      {Term,Bin_sz} = binary_to_term_stress(BinU, [used]),
+
+                      BinUE = make_unaligned_sub_binary(BinE),
+		      {Term,Bin_sz} = binary_to_term_stress(BinUE, [used]),
+
 		      BinC = erlang:term_to_binary(Term, [compressed]),
+                      BinC_sz = byte_size(BinC),
+		      true = BinC_sz =< size(Bin),
 		      Term = binary_to_term_stress(BinC),
-		      true = size(BinC) =< size(Bin),
+		      {Term, BinC_sz} = binary_to_term_stress(BinC, [used]),
+
 		      Bin = term_to_binary(Term, [{compressed,0}]),
 		      terms_compression_levels(Term, size(Bin), 1),
-		      UnalignedC = make_unaligned_sub_binary(BinC),
-		      Term = binary_to_term_stress(UnalignedC)
+
+		      BinUC = make_unaligned_sub_binary(BinC),
+		      Term = binary_to_term_stress(BinUC),
+                      {Term,BinC_sz} = binary_to_term_stress(BinUC, [used]),
+
+                      BinCE = <<BinC/binary, 1, 2, 3>>,
+		      {Term,BinC_sz} = binary_to_term_stress(BinCE, [used]),
+
+		      BinUCE = make_unaligned_sub_binary(BinCE),
+		      Term = binary_to_term_stress(BinUCE),
+                      {Term,BinC_sz} = binary_to_term_stress(BinUCE, [used])
 	      end,
     test_terms(TestFun),
     ok.
 
+%% Test binary_to_term(_, [used]) returning a big Used integer.
+b2t_used_big(_Config) ->
+    case erlang:system_info(wordsize) of
+        8 ->
+            {skipped, "This is not a 32-bit machine"};
+        4 ->
+            %% Use a long utf8 atom for large external format but compact on heap.
+            BigAtom = binary_to_atom(<< <<16#F0908D88:32>> || _ <- lists:seq(1,255) >>,
+                                     utf8),
+            Atoms = (1 bsl 17) + (1 bsl 9),
+            BigAtomList = lists:duplicate(Atoms, BigAtom),
+            BigBin = term_to_binary(BigAtomList),
+            {BigAtomList, Used} = binary_to_term(BigBin, [used]),
+            2 = erts_debug:size(Used),
+            Used = byte_size(BigBin),
+            Used = 1 + 1 + 4 + Atoms*(1+2+4*255) + 1,
+            ok
+    end.
+
 terms_compression_levels(Term, UncompressedSz, Level) when Level < 10 ->
     BinC = erlang:term_to_binary(Term, [{compressed,Level}]),
     Term = binary_to_term_stress(BinC),
@@ -1160,7 +1202,7 @@ very_big_num(0, Result) ->
     Result.
 
 make_port() ->
-    open_port({spawn, efile}, [eof]).
+    hd(erlang:ports()).
 
 make_pid() ->
     spawn_link(?MODULE, sleeper, []).
@@ -1261,40 +1303,28 @@ deep_roundtrip(T) ->
     B = term_to_binary(T),
     T = binary_to_term(B).
 
-obsolete_funs(Config) when is_list(Config) ->
+term2bin_tuple_fallbacks(Config) when is_list(Config) ->
     erts_debug:set_internal_state(available_internal_state, true),
 
-    X = id({1,2,3}),
-    Y = id([a,b,c,d]),
-    Z = id({x,y,z}),
-    obsolete_fun(fun() -> ok end),
-    obsolete_fun(fun() -> X end),
-    obsolete_fun(fun(A) -> {A,X} end),
-    obsolete_fun(fun() -> {X,Y} end),
-    obsolete_fun(fun() -> {X,Y,Z} end),
-
-    obsolete_fun(fun ?MODULE:all/1),
+    term2bin_tf(fun ?MODULE:all/1),
+    term2bin_tf(<<1:1>>),
+    term2bin_tf(<<90,80:7>>),
 
     erts_debug:set_internal_state(available_internal_state, false),
     ok.
 
-obsolete_fun(Fun) ->
-    Tuple = case erlang:fun_info(Fun, type) of
-		{type,external} ->
-		    {module,M} = erlang:fun_info(Fun, module),
-		    {name,F} = erlang:fun_info(Fun, name),
-		    {M,F};
-		{type,local} ->
-		    {module,M} = erlang:fun_info(Fun, module),
-		    {index,I} = erlang:fun_info(Fun, index),
-		    {uniq,U} = erlang:fun_info(Fun, uniq),
-		    {env,E} = erlang:fun_info(Fun, env),
-		    {'fun',M,I,U,list_to_tuple(E)}
-	    end,
-    Tuple = no_fun_roundtrip(Fun).
-
-no_fun_roundtrip(Term) ->
-    binary_to_term_stress(erts_debug:get_internal_state({term_to_binary_no_funs,Term})).
+term2bin_tf(Term) ->
+    Tuple = case Term of
+                Fun when is_function(Fun) ->
+                    {type, external} = erlang:fun_info(Fun, type),
+                    {module,M} = erlang:fun_info(Fun, module),
+                    {name,F} = erlang:fun_info(Fun, name),
+                    {M,F};
+                BS when bit_size(BS) rem 8 =/= 0 ->
+                    Bits = bit_size(BS) rem 8,
+                    {<<BS/bitstring, 0:(8-Bits)>>, Bits}
+            end,
+    Tuple = binary_to_term_stress(erts_debug:get_internal_state({term_to_binary_tuple_fallbacks,Term})).
 
 %% Test non-standard encodings never generated by term_to_binary/1
 %% but recognized by binary_to_term/1.
@@ -1442,13 +1472,13 @@ error_after_yield(Type, M, F, AN, AFun, TrapFunc) ->
 					   apply(M, F, A),
 					   exit({unexpected_success, {M, F, A}})
 				       catch
-					   error:Type ->
+					   error:Type:Stk ->
 					       erlang:trace(self(),false,[running,{tracer,Tracer}]),
 					       %% We threw the exception from the native
 					       %% function we trapped to, but we want
 					       %% the BIF that originally was called
 					       %% to appear in the stack trace.
-					       [{M, F, A, _} | _] = erlang:get_stacktrace()
+					       [{M, F, A, _} | _] = Stk
 				       end
 			       end),
     receive
diff --git a/erts/emulator/test/call_trace_SUITE.erl b/erts/emulator/test/call_trace_SUITE.erl
index 1251d644ae..d19f7f81ad 100644
--- a/erts/emulator/test/call_trace_SUITE.erl
+++ b/erts/emulator/test/call_trace_SUITE.erl
@@ -1116,8 +1116,8 @@ get_deep_4_loc(Arg) ->
         deep_4(Arg),
         ct:fail(should_not_return_to_here)
     catch
-        _:_ ->
-            [{?MODULE,deep_4,1,Loc0}|_] = erlang:get_stacktrace(),
+        _:_:Stk ->
+            [{?MODULE,deep_4,1,Loc0}|_] = Stk,
             Loc0
     end.
 
diff --git a/erts/emulator/test/ddll_SUITE.erl b/erts/emulator/test/ddll_SUITE.erl
index 031b05790d..4998fc08be 100644
--- a/erts/emulator/test/ddll_SUITE.erl
+++ b/erts/emulator/test/ddll_SUITE.erl
@@ -775,7 +775,7 @@ errors(Config) when is_list(Config) ->
     {error, bad_driver_name} = erl_ddll:load_driver(Path, wrongname_drv),
 
     %% We assume that there is a statically linked driver named "ddll":
-    {error, linked_in_driver} = erl_ddll:unload_driver(efile),
+    {error, linked_in_driver} = erl_ddll:unload_driver(ram_file_drv),
     {error, not_loaded} = erl_ddll:unload_driver("__pucko_driver__"),
 
     case os:type() of
diff --git a/erts/emulator/test/decode_packet_SUITE.erl b/erts/emulator/test/decode_packet_SUITE.erl
index 54ee4d5567..0ccdbd7ee8 100644
--- a/erts/emulator/test/decode_packet_SUITE.erl
+++ b/erts/emulator/test/decode_packet_SUITE.erl
@@ -239,7 +239,7 @@ packet_size(Config) when is_list(Config) ->
     %% Test OTP-9389, long HTTP header lines.
     Opts = [{packet_size, 128}],
     Pkt = list_to_binary(["GET / HTTP/1.1\r\nHost: localhost\r\nLink: /",
-                          string:chars($Y, 64), "\r\n\r\n"]),
+                          lists:duplicate(64, $Y), "\r\n\r\n"]),
     <<Pkt1:50/binary, Pkt2/binary>> = Pkt,
     {ok, {http_request,'GET',{abs_path,"/"},{1,1}}, Rest1} =
     erlang:decode_packet(http, Pkt1, Opts),
@@ -250,7 +250,7 @@ packet_size(Config) when is_list(Config) ->
     erlang:decode_packet(httph, list_to_binary([Rest2, Pkt2]), Opts),
 
     Pkt3 = list_to_binary(["GET / HTTP/1.1\r\nHost: localhost\r\nLink: /",
-                           string:chars($Y, 129), "\r\n\r\n"]),
+                           lists:duplicate(129, $Y), "\r\n\r\n"]),
     {ok, {http_request,'GET',{abs_path,"/"},{1,1}}, Rest3} =
     erlang:decode_packet(http, Pkt3, Opts),
     {ok, {http_header,_,'Host',_,"localhost"}, Rest4} =
@@ -509,9 +509,9 @@ decode_line(Bin,MaxLen) ->
     end.
 
 find_in_binary(Byte, Bin) ->
-    case string:chr(binary_to_list(Bin),Byte) of
-        0 -> notfound;	    
-        P -> P
+    case string:find(Bin, [Byte]) of
+        nomatch -> notfound;
+        Suffix -> byte_size(Bin) - byte_size(Suffix) + 1
     end.    
 
 ssl(Config) when is_list(Config) ->
@@ -562,7 +562,7 @@ decode_pkt(Type,Bin,Opts) ->
 otp_9389(Config) when is_list(Config) ->
     Opts = [{packet_size, 16384}, {line_length, 3000}],
     Pkt = list_to_binary(["GET / HTTP/1.1\r\nHost: localhost\r\nLink: /",
-                          string:chars($X, 8192),
+                          lists:duplicate(8192, $X),
                           "\r\nContent-Length: 0\r\n\r\n"]),
     <<Pkt1:5000/binary, Pkt2/binary>> = Pkt,
     {ok, {http_request,'GET',{abs_path,"/"},{1,1}}, Rest1} =
diff --git a/erts/emulator/test/dirty_bif_SUITE.erl b/erts/emulator/test/dirty_bif_SUITE.erl
index 981ec4d48d..46eb0cba58 100644
--- a/erts/emulator/test/dirty_bif_SUITE.erl
+++ b/erts/emulator/test/dirty_bif_SUITE.erl
@@ -108,90 +108,80 @@ dirty_bif_exception(Config) when is_list(Config) ->
 			      erts_debug:dirty_cpu(error, Error),
 			      ct:fail(expected_exception)
 			  catch
-			      error:ErrorType ->
-				  [{erts_debug,dirty_cpu,[error, Error],_}|_]
-				      = erlang:get_stacktrace(),
+			      error:ErrorType:Stk1 ->
+				  [{erts_debug,dirty_cpu,[error, Error],_}|_] = Stk1,
 				  ok
 			  end,
 			  try
 			      apply(erts_debug,dirty_cpu,[error, Error]),
 			      ct:fail(expected_exception)
 			  catch
-			      error:ErrorType ->
-				  [{erts_debug,dirty_cpu,[error, Error],_}|_]
-				      = erlang:get_stacktrace(),
+			      error:ErrorType:Stk2 ->
+				  [{erts_debug,dirty_cpu,[error, Error],_}|_] = Stk2,
 				  ok
 			  end,
 			  try
 			      erts_debug:dirty_io(error, Error),
 			      ct:fail(expected_exception)
 			  catch
-			      error:ErrorType ->
-				  [{erts_debug,dirty_io,[error, Error],_}|_]
-				      = erlang:get_stacktrace(),
+			      error:ErrorType:Stk3 ->
+				  [{erts_debug,dirty_io,[error, Error],_}|_] = Stk3,
 				  ok
 			  end,
 			  try
 			      apply(erts_debug,dirty_io,[error, Error]),
 			      ct:fail(expected_exception)
 			  catch
-			      error:ErrorType ->
-				  [{erts_debug,dirty_io,[error, Error],_}|_]
-				      = erlang:get_stacktrace(),
+			      error:ErrorType:Stk4 ->
+				  [{erts_debug,dirty_io,[error, Error],_}|_] = Stk4,
 				  ok
 			  end,
 			  try
 			      erts_debug:dirty(normal, error, Error),
 			      ct:fail(expected_exception)
 			  catch
-			      error:ErrorType ->
-				  [{erts_debug,dirty,[normal, error, Error],_}|_]
-				      = erlang:get_stacktrace(),
+			      error:ErrorType:Stk5 ->
+				  [{erts_debug,dirty,[normal, error, Error],_}|_] = Stk5,
 				  ok
 			  end,
 			  try
 			      apply(erts_debug,dirty,[normal, error, Error]),
 			      ct:fail(expected_exception)
 			  catch
-			      error:ErrorType ->
-				  [{erts_debug,dirty,[normal, error, Error],_}|_]
-				      = erlang:get_stacktrace(),
+			      error:ErrorType:Stk6 ->
+				  [{erts_debug,dirty,[normal, error, Error],_}|_] = Stk6,
 				  ok
 			  end,
 			  try
 			      erts_debug:dirty(dirty_cpu, error, Error),
 			      ct:fail(expected_exception)
 			  catch
-			      error:ErrorType ->
-				  [{erts_debug,dirty,[dirty_cpu, error, Error],_}|_]
-				      = erlang:get_stacktrace(),
+			      error:ErrorType:Stk7 ->
+				  [{erts_debug,dirty,[dirty_cpu, error, Error],_}|_] = Stk7,
 				  ok
 			  end,
 			  try
 			      apply(erts_debug,dirty,[dirty_cpu, error, Error]),
 			      ct:fail(expected_exception)
 			  catch
-			      error:ErrorType ->
-				  [{erts_debug,dirty,[dirty_cpu, error, Error],_}|_]
-				      = erlang:get_stacktrace(),
+			      error:ErrorType:Stk8 ->
+				  [{erts_debug,dirty,[dirty_cpu, error, Error],_}|_] = Stk8,
 				  ok
 			  end,
 			  try
 			      erts_debug:dirty(dirty_io, error, Error),
 			      ct:fail(expected_exception)
 			  catch
-			      error:ErrorType ->
-				  [{erts_debug,dirty,[dirty_io, error, Error],_}|_]
-				      = erlang:get_stacktrace(),
+			      error:ErrorType:Stk9 ->
+				  [{erts_debug,dirty,[dirty_io, error, Error],_}|_] = Stk9,
 				  ok
 			  end,
 			  try
 			      apply(erts_debug,dirty,[dirty_io, error, Error]),
 			      ct:fail(expected_exception)
 			  catch
-			      error:ErrorType ->
-				  [{erts_debug,dirty,[dirty_io, error, Error],_}|_]
-				      = erlang:get_stacktrace(),
+			      error:ErrorType:Stk10 ->
+				  [{erts_debug,dirty,[dirty_io, error, Error],_}|_] = Stk10,
 				  ok
 			  end
 		  end,
@@ -204,25 +194,22 @@ dirty_bif_multischedule_exception(Config) when is_list(Config) ->
     try
 	erts_debug:dirty_cpu(reschedule,1001)
     catch
-	error:badarg ->
-	    [{erts_debug,dirty_cpu,[reschedule, 1001],_}|_]
-		= erlang:get_stacktrace(),
+	error:badarg:Stk1 ->
+	    [{erts_debug,dirty_cpu,[reschedule, 1001],_}|_] = Stk1,
 	    ok
     end,
     try
 	erts_debug:dirty_io(reschedule,1001)
     catch
-	error:badarg ->
-	    [{erts_debug,dirty_io,[reschedule, 1001],_}|_]
-		= erlang:get_stacktrace(),
+	error:badarg:Stk2 ->
+	    [{erts_debug,dirty_io,[reschedule, 1001],_}|_] = Stk2,
 	    ok
     end,
     try
 	erts_debug:dirty(normal,reschedule,1001)
     catch
-	error:badarg ->
-	    [{erts_debug,dirty,[normal,reschedule,1001],_}|_]
-		= erlang:get_stacktrace(),
+	error:badarg:Stk3 ->
+	    [{erts_debug,dirty,[normal,reschedule,1001],_}|_] = Stk3,
 	    ok
     end.
 
@@ -230,6 +217,11 @@ dirty_scheduler_exit(Config) when is_list(Config) ->
     {ok, Node} = start_node(Config, "+SDio 1"),
     [ok] = mcall(Node,
                  [fun() ->
+                          %% Perform a dry run to ensure that all required code
+                          %% is loaded. Otherwise the test will fail since code
+                          %% loading is done through dirty IO and it won't make
+                          %% any progress during this test.
+                          _DryRun = test_dirty_scheduler_exit(),
 			  Start = erlang:monotonic_time(millisecond),
                           ok = test_dirty_scheduler_exit(),
 			  End = erlang:monotonic_time(millisecond),
@@ -246,23 +238,22 @@ test_dse(0,Pids) ->
     timer:sleep(100),
     kill_dse(Pids,[]);
 test_dse(N,Pids) ->
-    Pid = spawn_link(fun () -> erts_debug:dirty_io(wait, 5000) end),
+    Pid = spawn_link(fun () -> erts_debug:dirty_io(wait, 1000) end),
     test_dse(N-1,[Pid|Pids]).
 
 kill_dse([],Killed) ->
-    wait_dse(Killed);
+    wait_dse(Killed, ok);
 kill_dse([Pid|Pids],AlreadyKilled) ->
     exit(Pid,kill),
     kill_dse(Pids,[Pid|AlreadyKilled]).
 
-wait_dse([]) ->
-    ok;
-wait_dse([Pid|Pids]) ->
+wait_dse([], Result) ->
+    Result;
+wait_dse([Pid|Pids], Result) ->
     receive
-        {'EXIT',Pid,Reason} ->
-	    killed = Reason
-    end,
-    wait_dse(Pids).
+        {'EXIT', Pid, killed} -> wait_dse(Pids, Result);
+        {'EXIT', Pid, _Other} -> wait_dse(Pids, failed)
+    end.
 
 dirty_call_while_terminated(Config) when is_list(Config) ->
     Me = self(),
diff --git a/erts/emulator/test/dirty_nif_SUITE.erl b/erts/emulator/test/dirty_nif_SUITE.erl
index 13806fd5c4..93d0ac392c 100644
--- a/erts/emulator/test/dirty_nif_SUITE.erl
+++ b/erts/emulator/test/dirty_nif_SUITE.erl
@@ -109,9 +109,8 @@ dirty_nif_exception(Config) when is_list(Config) ->
 	call_dirty_nif_exception(1),
 	ct:fail(expected_badarg)
     catch
-	error:badarg ->
-	    [{?MODULE,call_dirty_nif_exception,[1],_}|_] =
-		erlang:get_stacktrace(),
+	error:badarg:Stk1 ->
+	    [{?MODULE,call_dirty_nif_exception,[1],_}|_] = Stk1,
 	    ok
     end,
     try
@@ -121,9 +120,8 @@ dirty_nif_exception(Config) when is_list(Config) ->
 	call_dirty_nif_exception(0),
 	ct:fail(expected_badarg)
     catch
-	error:badarg ->
-	    [{?MODULE,call_dirty_nif_exception,[0],_}|_] =
-		erlang:get_stacktrace(),
+	error:badarg:Stk2 ->
+	    [{?MODULE,call_dirty_nif_exception,[0],_}|_] = Stk2,
 	    ok
     end,
     %% this checks that a dirty NIF can raise various terms as
@@ -138,8 +136,8 @@ nif_raise_exceptions(NifFunc) ->
                             erlang:apply(?MODULE,NifFunc,[Term]),
                             ct:fail({expected,Term})
                         catch
-                            error:Term ->
-                                [{?MODULE,NifFunc,[Term],_}|_] = erlang:get_stacktrace(),
+                            error:Term:Stk ->
+                                [{?MODULE,NifFunc,[Term],_}|_] = Stk,
                                 ok
                         end
                 end, ok, ExcTerms).
@@ -151,6 +149,11 @@ dirty_scheduler_exit(Config) when is_list(Config) ->
     [ok] = mcall(Node,
                  [fun() ->
                           ok = erlang:load_nif(NifLib, []),
+                          %% Perform a dry run to ensure that all required code
+                          %% is loaded. Otherwise the test will fail since code
+                          %% loading is done through dirty IO and it won't make
+                          %% any progress during this test.
+                          _DryRun = test_dirty_scheduler_exit(),
 			  Start = erlang:monotonic_time(millisecond),
                           ok = test_dirty_scheduler_exit(),
 			  End = erlang:monotonic_time(millisecond),
@@ -171,19 +174,18 @@ test_dse(N,Pids) ->
     test_dse(N-1,[Pid|Pids]).
 
 kill_dse([],Killed) ->
-    wait_dse(Killed);
+    wait_dse(Killed, ok);
 kill_dse([Pid|Pids],AlreadyKilled) ->
     exit(Pid,kill),
     kill_dse(Pids,[Pid|AlreadyKilled]).
 
-wait_dse([]) ->
-    ok;
-wait_dse([Pid|Pids]) ->
+wait_dse([], Result) ->
+    Result;
+wait_dse([Pid|Pids], Result) ->
     receive
-        {'EXIT',Pid,Reason} ->
-	    killed = Reason
-    end,
-    wait_dse(Pids).
+        {'EXIT', Pid, killed} -> wait_dse(Pids, Result);
+        {'EXIT', Pid, _Other} -> wait_dse(Pids, failed)
+    end.
 
 dirty_call_while_terminated(Config) when is_list(Config) ->
     Me = self(),
@@ -287,9 +289,9 @@ access_dirty_heap(Dirty, RGL, N, R) ->
 %% dirty NIF where the main lock is needed for that access do not get
 %% blocked. Each test passes its pid to dirty_sleeper, which sends a
 %% 'ready' message when it's running on a dirty scheduler and just before
-%% it starts a 6 second sleep. When it receives the message, it verifies
+%% it starts a 2 second sleep. When it receives the message, it verifies
 %% that access to the dirty process is as it expects.  After the dirty
-%% process finishes its 6 second sleep but before it returns from the dirty
+%% process finishes its 2 second sleep but before it returns from the dirty
 %% scheduler, it sends a 'done' message. If the tester already received
 %% that message, the test fails because it means attempting to access the
 %% dirty process waited for that process to return to a regular scheduler,
@@ -353,7 +355,7 @@ dirty_process_trace(Config) when is_list(Config) ->
 			      error(missing_trace_return_message)
 		      end
 	      after
-		  6500 ->
+		  2500 ->
 		      error(missing_done_message)
 	      end,
 	      ok
@@ -380,7 +382,7 @@ code_purge(Config) when is_list(Config) ->
     Start = erlang:monotonic_time(),
     {Pid1, Mon1} = spawn_monitor(fun () ->
 				       dirty_code_test:func(fun () ->
-								    %% Sleep for 6 seconds
+								    %% Sleep for 2 seconds
 								    %% in dirty nif...
 								    dirty_sleeper()
 							    end)
@@ -388,7 +390,7 @@ code_purge(Config) when is_list(Config) ->
     {module, dirty_code_test} = erlang:load_module(dirty_code_test, Bin),
     {Pid2, Mon2} = spawn_monitor(fun () ->
 				       dirty_code_test:func(fun () ->
-								    %% Sleep for 6 seconds
+								    %% Sleep for 2 seconds
 								    %% in dirty nif...
 								    dirty_sleeper()
 							    end)
@@ -490,7 +492,7 @@ test_dirty_process_access(Start, Test, Finish) ->
 			 ok
 		 end
 	 after
-	     3000 ->
+	     1000 ->
 		 error(timeout)
 	 end,
     ok = Finish(NifPid).
diff --git a/erts/emulator/test/dirty_nif_SUITE_data/dirty_nif_SUITE.c b/erts/emulator/test/dirty_nif_SUITE_data/dirty_nif_SUITE.c
index 0321b9898f..2a8b999307 100644
--- a/erts/emulator/test/dirty_nif_SUITE_data/dirty_nif_SUITE.c
+++ b/erts/emulator/test/dirty_nif_SUITE_data/dirty_nif_SUITE.c
@@ -217,9 +217,9 @@ dirty_sleeper(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
     }
 
 #ifdef __WIN32__
-    Sleep(6000);
+    Sleep(2000);
 #else
-    sleep(6);
+    sleep(2);
 #endif
 
     if (argc == 1) {
diff --git a/erts/emulator/test/distribution_SUITE.erl b/erts/emulator/test/distribution_SUITE.erl
index e731b68f2f..e40d346e10 100644
--- a/erts/emulator/test/distribution_SUITE.erl
+++ b/erts/emulator/test/distribution_SUITE.erl
@@ -35,13 +35,18 @@
 
 -include_lib("common_test/include/ct.hrl").
 
+%-define(Line, erlang:display({line,?LINE}),).
+-define(Line,).
+
 -export([all/0, suite/0, groups/0,
          ping/1, bulk_send_small/1,
+         group_leader/1,
+         optimistic_dflags/1,
          bulk_send_big/1, bulk_send_bigbig/1,
          local_send_small/1, local_send_big/1,
          local_send_legal/1, link_to_busy/1, exit_to_busy/1,
          lost_exit/1, link_to_dead/1, link_to_dead_new_node/1,
-         applied_monitor_node/1, ref_port_roundtrip/1, nil_roundtrip/1,
+         ref_port_roundtrip/1, nil_roundtrip/1,
          trap_bif_1/1, trap_bif_2/1, trap_bif_3/1,
          stop_dist/1,
          dist_auto_connect_never/1, dist_auto_connect_once/1,
@@ -61,6 +66,8 @@
 
 %% Internal exports.
 -export([sender/3, receiver2/2, dummy_waiter/0, dead_process/0,
+         group_leader_1/1,
+         optimistic_dflags_echo/0, optimistic_dflags_sender/1,
          roundtrip/1, bounce/1, do_dist_auto_connect/1, inet_rpc_server/1,
          dist_parallel_sender/3, dist_parallel_receiver/0,
          dist_evil_parallel_receiver/0]).
@@ -74,8 +81,10 @@ suite() ->
 
 all() ->
     [ping, {group, bulk_send}, {group, local_send},
+     group_leader,
+     optimistic_dflags,
      link_to_busy, exit_to_busy, lost_exit, link_to_dead,
-     link_to_dead_new_node, applied_monitor_node,
+     link_to_dead_new_node,
      ref_port_roundtrip, nil_roundtrip, stop_dist,
      {group, trap_bif}, {group, dist_auto_connect},
      dist_parallel_send, atom_roundtrip, unicode_atom_roundtrip,
@@ -124,6 +133,96 @@ ping(Config) when is_list(Config) ->
 
     ok.
 
+%% Test erlang:group_leader(_, ExternalPid), i.e. DOP_GROUP_LEADER
+group_leader(Config) when is_list(Config) ->
+    ?Line Sock = start_relay_node(group_leader_1, []),
+    ?Line Sock2 = start_relay_node(group_leader_2, []),
+    try
+        ?Line Node2 = inet_rpc_nodename(Sock2),
+        ?Line {ok, ok} = do_inet_rpc(Sock, ?MODULE, group_leader_1, [Node2])
+    after
+        ?Line stop_relay_node(Sock),
+        ?Line stop_relay_node(Sock2)
+    end,
+    ok.
+
+group_leader_1(Node2) ->
+    ?Line ExtPid = spawn(Node2, fun F() ->
+                                        receive {From, group_leader} ->
+                                                From ! {self(), group_leader, group_leader()}
+                                        end,
+                                        F()
+                                end),
+    ?Line GL1 = self(),
+    ?Line group_leader(GL1, ExtPid),
+    ?Line ExtPid ! {self(), group_leader},
+    ?Line {ExtPid, group_leader, GL1} = receive_one(),
+
+    %% Kill connection and repeat test when group_leader/2 triggers auto-connect
+    ?Line net_kernel:monitor_nodes(true),
+    ?Line net_kernel:disconnect(Node2),
+    ?Line {nodedown, Node2} = receive_one(),
+    ?Line GL2 = spawn(fun() -> dummy end),
+    ?Line group_leader(GL2, ExtPid),
+    ?Line {nodeup, Node2} = receive_one(),
+    ?Line ExtPid ! {self(), group_leader},
+    ?Line {ExtPid, group_leader, GL2} = receive_one(),
+    ok.
+
+%% Test optimistic distribution flags toward pending connections (DFLAG_DIST_HOPEFULLY)
+optimistic_dflags(Config) when is_list(Config) ->
+    ?Line Sender = start_relay_node(optimistic_dflags_sender, []),
+    ?Line Echo = start_relay_node(optimistic_dflags_echo, []),
+    try
+        ?Line {ok, ok} = do_inet_rpc(Echo, ?MODULE, optimistic_dflags_echo, []),
+
+        ?Line EchoNode = inet_rpc_nodename(Echo),
+        ?Line {ok, ok} = do_inet_rpc(Sender, ?MODULE, optimistic_dflags_sender, [EchoNode])
+    after
+        ?Line stop_relay_node(Sender),
+        ?Line stop_relay_node(Echo)
+    end,
+    ok.
+
+optimistic_dflags_echo() ->
+    P = spawn(fun F() ->
+                      receive {From, Term} ->
+                              From ! {self(), Term}
+                      end,
+                      F()
+              end),
+    register(optimistic_dflags_echo, P),
+    optimistic_dflags_echo ! {self(), hello},
+    {P, hello} = receive_one(),
+    ok.
+
+optimistic_dflags_sender(EchoNode) ->
+    ?Line net_kernel:monitor_nodes(true),
+
+    optimistic_dflags_do(EchoNode, <<1:1>>),
+    optimistic_dflags_do(EchoNode, fun lists:map/2),
+    ok.
+
+optimistic_dflags_do(EchoNode, Term) ->
+    ?Line {optimistic_dflags_echo, EchoNode} ! {self(), Term},
+    ?Line {nodeup, EchoNode} = receive_one(),
+    ?Line {EchoPid, Term} = receive_one(),
+    %% repeat with pid destination
+    ?Line net_kernel:disconnect(EchoNode),
+    ?Line {nodedown, EchoNode} = receive_one(),
+    ?Line EchoPid ! {self(), Term},
+    ?Line {nodeup, EchoNode} = receive_one(),
+    ?Line {EchoPid, Term} = receive_one(),
+
+    ?Line net_kernel:disconnect(EchoNode),
+    ?Line {nodedown, EchoNode} = receive_one(),
+    ok.
+
+
+receive_one() ->
+    receive M -> M after 1000 -> timeout end.
+
+
 bulk_send_small(Config) when is_list(Config) ->
     bulk_send(64, 32).
 
@@ -420,18 +519,20 @@ make_busy(Node, Time) when is_integer(Time) ->
     Own = 500,
     freeze_node(Node, Time+Own),
     Data = make_busy_data(),
+    DCtrl = dctrl(Node),
     %% first make port busy
     Pid = spawn_link(fun () ->
                              forever(fun () ->
-                                             dport_reg_send(Node,
-                                                            '__noone__',
-                                                            Data)
+                                             dctrl_dop_reg_send(Node,
+                                                                '__noone__',
+                                                                Data)
                                      end)
                      end),
     receive after Own -> ok end,
     until(fun () ->
-                  case process_info(Pid, status) of
-                      {status, suspended} -> true;
+                  case {DCtrl, process_info(Pid, status)} of
+                      {DPrt, {status, suspended}} when is_port(DPrt) -> true;
+                      {DPid, {status, waiting}} when is_pid(DPid) -> true;
                       _ -> false
                   end
           end),
@@ -637,31 +738,11 @@ link_to_dead_new_node(Config) when is_list(Config) ->
     end,
     ok.
 
-%% Test that monitor_node/2 works when applied.
-applied_monitor_node(Config) when is_list(Config) ->
-    NonExisting = list_to_atom("__non_existing__@" ++ hostname()),
-
-    %% Tail-recursive call to apply (since the node is non-existing,
-    %% there will be a trap).
-
-    true = tail_apply(erlang, monitor_node, [NonExisting, true]),
-    [{nodedown, NonExisting}] = test_server:messages_get(),
-
-    %% Ordinary call (with trap).
-
-    true = apply(erlang, monitor_node, [NonExisting, true]),
-    [{nodedown, NonExisting}] = test_server:messages_get(),
-
-    ok.
-
-tail_apply(M, F, A) ->
-    apply(M, F, A).
-
 %% Test that sending a port or reference to another node and back again
 %% doesn't correct them in any way.
 ref_port_roundtrip(Config) when is_list(Config) ->
     process_flag(trap_exit, true),
-    Port = open_port({spawn, efile}, []),
+    Port = make_port(),
     Ref = make_ref(),
     {ok, Node} = start_node(ref_port_roundtrip),
     net_adm:ping(Node),
@@ -682,6 +763,9 @@ ref_port_roundtrip(Config) when is_list(Config) ->
     end,
     ok.
 
+make_port() ->
+    hd(erlang:ports()).
+
 roundtrip(Term) ->
     exit(Term).
 
@@ -784,8 +868,8 @@ dist_auto_connect_once(Config) when is_list(Config) ->
     {ok, pong} = do_inet_rpc(Sock2,net_adm,ping,[NN]),
     {ok,[NN2]} = do_inet_rpc(Sock,erlang,nodes,[]),
     {ok,[NN]} = do_inet_rpc(Sock2,erlang,nodes,[]),
-    [_,HostPartPeer] = string:tokens(atom_to_list(NN),"@"),
-    [_,MyHostPart] = string:tokens(atom_to_list(node()),"@"),
+    [_,HostPartPeer] = string:lexemes(atom_to_list(NN),"@"),
+    [_,MyHostPart] = string:lexemes(atom_to_list(node()),"@"),
     % Give net_kernel a chance to change the state of the node to up to.
     receive after 1000 -> ok end,
     case HostPartPeer of
@@ -1156,8 +1240,6 @@ contended_atom_cache_entry_test(Config, Type) ->
     spawn_link(
       SNode,
       fun () ->
-              erts_debug:set_internal_state(available_internal_state,
-                                            true),
               Master = self(),
               CIX = get_cix(),
               TestAtoms = case Type of
@@ -1242,7 +1324,7 @@ get_cix(CIX) when is_integer(CIX), CIX < 0 ->
 get_cix(CIX) when is_integer(CIX) ->
     get_cix(CIX,
             unwanted_cixs(),
-            erts_debug:get_internal_state(max_atom_out_cache_index)).
+            get_internal_state(max_atom_out_cache_index)).
 
 get_cix(CIX, Unwanted, MaxCIX) when CIX > MaxCIX ->
     get_cix(0, Unwanted, MaxCIX);
@@ -1254,8 +1336,8 @@ get_cix(CIX, Unwanted, MaxCIX) ->
 
 unwanted_cixs() ->
     lists:map(fun (Node) ->
-                      erts_debug:get_internal_state({atom_out_cache_index,
-                                                     Node})
+                      get_internal_state({atom_out_cache_index,
+                                          Node})
               end,
               nodes()).
 
@@ -1264,7 +1346,7 @@ get_conflicting_atoms(_CIX, 0) ->
     [];
 get_conflicting_atoms(CIX, N) ->
     Atom = list_to_atom("atom" ++ integer_to_list(erlang:unique_integer([positive]))),
-    case erts_debug:get_internal_state({atom_out_cache_index, Atom}) of
+    case get_internal_state({atom_out_cache_index, Atom}) of
         CIX ->
             [Atom|get_conflicting_atoms(CIX, N-1)];
         _ ->
@@ -1275,7 +1357,7 @@ get_conflicting_unicode_atoms(_CIX, 0) ->
     [];
 get_conflicting_unicode_atoms(CIX, N) ->
     Atom = string_to_atom([16#1f608] ++ "atom" ++ integer_to_list(erlang:unique_integer([positive]))),
-    case erts_debug:get_internal_state({atom_out_cache_index, Atom}) of
+    case get_internal_state({atom_out_cache_index, Atom}) of
         CIX ->
             [Atom|get_conflicting_unicode_atoms(CIX, N-1)];
         _ ->
@@ -1738,37 +1820,38 @@ bad_dist_ext_check_msgs([M|Ms]) ->
             bad_dist_ext_check_msgs(Ms)
     end.
 
+ensure_dctrl(Node) ->
+    case dctrl(Node) of
+        undefined ->
+            pong = net_adm:ping(Node),
+            dctrl(Node);
+        DCtrl ->
+            DCtrl
+    end.
 
-dport_reg_send(Node, Name, Msg) ->
-    DPrt = case dport(Node) of
-               undefined ->
-                   pong = net_adm:ping(Node),
-                   dport(Node);
-               Prt ->
-                   Prt
-           end,
-    port_command(DPrt, [dmsg_hdr(),
-                        dmsg_ext({?DOP_REG_SEND,
-                                  self(),
-                                  ?COOKIE,
-                                  Name}),
-                        dmsg_ext(Msg)]).
-
-
-dport_send(To, Msg) ->
+dctrl_send(DPrt, Data) when is_port(DPrt) ->
+    port_command(DPrt, Data);
+dctrl_send(DPid, Data) when is_pid(DPid) ->
+    Ref = make_ref(),
+    DPid ! {send, self(), Ref, Data},
+    receive {Ref, Res} -> Res end.
+
+dctrl_dop_reg_send(Node, Name, Msg) ->
+    dctrl_send(ensure_dctrl(Node),
+               [dmsg_hdr(),
+                dmsg_ext({?DOP_REG_SEND,
+                          self(),
+                          ?COOKIE,
+                          Name}),
+                dmsg_ext(Msg)]).
+
+dctrl_dop_send(To, Msg) ->
     Node = node(To),
-    DPrt = case dport(Node) of
-               undefined ->
-                   pong = net_adm:ping(Node),
-                   dport(Node);
-               Prt ->
-                   Prt
-           end,
-    port_command(DPrt, [dmsg_hdr(),
-                        dmsg_ext({?DOP_SEND,
-                                  ?COOKIE,
-                                  To}),
-                        dmsg_ext(Msg)]).
+    dctrl_send(ensure_dctrl(Node),
+               [dmsg_hdr(),
+                dmsg_ext({?DOP_SEND, ?COOKIE, To}),
+                dmsg_ext(Msg)]).
+
 send_bad_structure(Offender,Victim,Bad,WhereToPutSelf) ->
     send_bad_structure(Offender,Victim,Bad,WhereToPutSelf,[]).
 send_bad_structure(Offender,Victim,Bad,WhereToPutSelf,PayLoad) ->
@@ -1779,7 +1862,7 @@ send_bad_structure(Offender,Victim,Bad,WhereToPutSelf,PayLoad) ->
                   Node = node(Victim),
                   pong = net_adm:ping(Node),
                   erlang:monitor_node(Node, true),
-                  DPrt = dport(Node),
+                  DCtrl = dctrl(Node),
                   Bad1 = case WhereToPutSelf of
                              0 ->
                                  Bad;
@@ -1797,7 +1880,7 @@ send_bad_structure(Offender,Victim,Bad,WhereToPutSelf,PayLoad) ->
                   after 10 -> ok
                   end,
 
-                  port_command(DPrt, DData),
+                  dctrl_send(DCtrl, DData),
 
                   receive {nodedown, Node} -> ok
                   after 5000 -> exit("missing nodedown")
@@ -1832,11 +1915,11 @@ send_bad_msgs(BadNode, To, Repeat, BadTerm) when is_atom(BadNode),
                fun () ->
                        Node = node(To),
                        pong = net_adm:ping(Node),
-                       DPrt = dport(Node),
+                       DCtrl = dctrl(Node),
                        DData = [dmsg_hdr(),
                                 dmsg_ext({?DOP_SEND, ?COOKIE, To}),
                                 BadTerm],
-                       repeat(fun () -> port_command(DPrt, DData) end, Repeat),
+		       repeat(fun () -> dctrl_send(DCtrl, DData) end, Repeat),
                        Parent ! Done
                end),
     receive Done -> ok end.
@@ -1858,11 +1941,12 @@ send_bad_ctl(BadNode, ToNode) when is_atom(BadNode), is_atom(ToNode) ->
                                        replace}),
                        CtlBeginSize = size(Ctl) - size(Replace),
                        <<CtlBegin:CtlBeginSize/binary, Replace/binary>> = Ctl,
-                       port_command(dport(ToNode),
-                                    [dmsg_fake_hdr2(),
-                                     CtlBegin,
-                                     dmsg_bad_atom_cache_ref(),
-                                     dmsg_ext({a, message})]),
+                       DCtrl = dctrl(ToNode),
+                       Data = [dmsg_fake_hdr2(),
+                               CtlBegin,
+                               dmsg_bad_atom_cache_ref(),
+                               dmsg_ext({a, message})],
+                       dctrl_send(DCtrl, Data),
                        Parent ! Done
                end),
     receive Done -> ok end.
@@ -1875,17 +1959,32 @@ send_bad_dhdr(BadNode, ToNode) when is_atom(BadNode), is_atom(ToNode) ->
     spawn_link(BadNode,
                fun () ->
                        pong = net_adm:ping(ToNode),
-                       port_command(dport(ToNode), dmsg_bad_hdr()),
+                       dctrl_send(dctrl(ToNode), dmsg_bad_hdr()),
                        Parent ! Done
                end),
     receive Done -> ok end.
 
-dport(Node) when is_atom(Node) ->
-    case catch erts_debug:get_internal_state(available_internal_state) of
-        true -> true;
-        _ -> erts_debug:set_internal_state(available_internal_state, true)
-    end,
-    erts_debug:get_internal_state({dist_port, Node}).
+dctrl(Node) when is_atom(Node) ->
+    get_internal_state({dist_ctrl, Node}).
+
+get_internal_state(Op) ->
+    try erts_debug:get_internal_state(Op) of
+        R -> R
+    catch
+        error:undef ->
+            erts_debug:set_internal_state(available_internal_state, true),
+            erts_debug:get_internal_state(Op)
+    end.
+
+set_internal_state(Op, Val) ->
+    try erts_debug:set_internal_state(Op, Val) of
+        R -> R
+    catch
+        error:undef ->
+            erts_debug:set_internal_state(available_internal_state, true),
+            erts_debug:set_internal_state(Op, Val)
+    end.
+
 
 dmsg_hdr() ->
     [131, % Version Magic
@@ -2028,11 +2127,9 @@ freeze_node(Node, MS) ->
     Freezer = self(),
     spawn_link(Node,
                fun () ->
-                       erts_debug:set_internal_state(available_internal_state,
-                                                     true),
-                       dport_send(Freezer, DoingIt),
+                       dctrl_dop_send(Freezer, DoingIt),
                        receive after Own -> ok end,
-                       erts_debug:set_internal_state(block, MS+Own)
+                       set_internal_state(block, MS+Own)
                end),
     receive DoingIt -> ok end,
     receive after Own -> ok end.
@@ -2082,7 +2179,7 @@ start_relay_node(Node, Args) ->
                                       [{args, Args ++
                                         " -setcookie "++Cookie++" -pa "++Pa++" "++
                                         RunArg}]),
-    [N,H] = string:tokens(atom_to_list(NN),"@"),
+    [N,H] = string:lexemes(atom_to_list(NN),"@"),
     {ok, Sock} = gen_tcp:accept(LSock),
     pang = net_adm:ping(NN),
     {N,H,Sock}.
@@ -2236,8 +2333,7 @@ forever(Fun) ->
     forever(Fun).
 
 abort(Why) ->
-    erts_debug:set_internal_state(available_internal_state, true),
-    erts_debug:set_internal_state(abort, Why).
+    set_internal_state(abort, Why).
 
 
 start_busy_dist_port_tracer() ->
diff --git a/erts/emulator/test/driver_SUITE.erl b/erts/emulator/test/driver_SUITE.erl
index 6810729285..6446d5f6d2 100644
--- a/erts/emulator/test/driver_SUITE.erl
+++ b/erts/emulator/test/driver_SUITE.erl
@@ -43,9 +43,9 @@
          outputv_errors/1,
          driver_unloaded/1,
          io_ready_exit/1,
+         use_fallback_pollset/0,
          use_fallback_pollset/1,
          bad_fd_in_pollset/1,
-         driver_event/1,
          fd_change/1,
          steal_control/1,
          otp_6602/1,
@@ -58,11 +58,9 @@
          ioq_exit_ready_output/1,
          ioq_exit_timeout/1,
          ioq_exit_ready_async/1,
-         ioq_exit_event/1,
          ioq_exit_ready_input_async/1,
          ioq_exit_ready_output_async/1,
          ioq_exit_timeout_async/1,
-         ioq_exit_event_async/1,
          zero_extended_marker_garb_drv/1,
          invalid_extended_marker_drv/1,
          larger_major_vsn_drv/1,
@@ -86,6 +84,8 @@
 
 -export([bin_prefix/2]).
 
+-export([get_check_io_total/1]).   % for z_SUITE.erl
+
 -include_lib("common_test/include/ct.hrl").
 
 
@@ -119,17 +119,26 @@
 -define(heap_binary_size, 64).
 
 init_per_testcase(Case, Config) when is_atom(Case), is_list(Config) ->
-    case catch erts_debug:get_internal_state(available_internal_state) of
-        true -> ok;
-        _ -> erts_debug:set_internal_state(available_internal_state, true)
-    end,
+    CIOD = rpc(Config,
+               fun() ->
+                       case catch erts_debug:get_internal_state(available_internal_state) of
+                           true -> ok;
+                           _ -> erts_debug:set_internal_state(available_internal_state, true)
+                       end,
+                       erts_debug:get_internal_state(check_io_debug)
+               end),
     erlang:display({init_per_testcase, Case}),
-    0 = element(1, erts_debug:get_internal_state(check_io_debug)),
+    0 = element(1, CIOD),
     [{testcase, Case}|Config].
 
-end_per_testcase(Case, _Config) ->
+end_per_testcase(Case, Config) ->
     erlang:display({end_per_testcase, Case}),
-    0 = element(1, erts_debug:get_internal_state(check_io_debug)),
+    CIOD = rpc(Config,
+               fun() ->
+                       get_stable_check_io_info(),
+                       erts_debug:get_internal_state(check_io_debug)
+               end),
+    0 = element(1, CIOD),
     ok.
 
 suite() ->
@@ -137,10 +146,13 @@ suite() ->
      {timetrap, {minutes, 1}}].
 
 all() -> %% Keep a_test first and z_test last...
-    [a_test, outputv_errors, outputv_echo, queue_echo, {group, timer},
-     driver_unloaded, io_ready_exit, use_fallback_pollset,
-     bad_fd_in_pollset, driver_event, fd_change,
-     steal_control, otp_6602, driver_system_info_base_ver,
+    [a_test, outputv_errors, outputv_echo, queue_echo,
+     {group, timer},
+     driver_unloaded, io_ready_exit, otp_6602,
+     {group, polling},
+     {group, poll_thread},
+     {group, poll_set},
+     driver_system_info_base_ver,
      driver_system_info_prev_ver,
      driver_system_info_current_ver, driver_monitor,
      {group, ioq_exit}, zero_extended_marker_garb_drv,
@@ -148,7 +160,6 @@ all() -> %% Keep a_test first and z_test last...
      larger_minor_vsn_drv, smaller_major_vsn_drv,
      smaller_minor_vsn_drv, peek_non_existing_queue,
      otp_6879, caller, many_events, missing_callbacks,
-     smp_select, driver_select_use,
      thread_mseg_alloc_cache_clean,
      otp_9302,
      thr_free_drv,
@@ -161,11 +172,18 @@ groups() ->
     [{timer, [],
       [timer_measure, timer_cancel, timer_delay,
        timer_change]},
+     {poll_thread, [], [{group, polling}]},
+     {poll_set, [], [{group, polling}]},
+     {polling, [],
+      [a_test, use_fallback_pollset,
+       bad_fd_in_pollset, fd_change,
+       steal_control, smp_select,
+       driver_select_use, z_test]},
      {ioq_exit, [],
       [ioq_exit_ready_input, ioq_exit_ready_output,
-       ioq_exit_timeout, ioq_exit_ready_async, ioq_exit_event,
+       ioq_exit_timeout, ioq_exit_ready_async,
        ioq_exit_ready_input_async, ioq_exit_ready_output_async,
-       ioq_exit_timeout_async, ioq_exit_event_async]}].
+       ioq_exit_timeout_async]}].
 
 init_per_suite(Config) ->
     Config.
@@ -173,10 +191,28 @@ init_per_suite(Config) ->
 end_per_suite(_Config) ->
     catch erts_debug:set_internal_state(available_internal_state, false).
 
+init_per_group(poll_thread, Config) ->
+    [{node_args, "+IOt 2"} | Config];
+init_per_group(poll_set, Config) ->
+    [{node_args, "+IOt 2 +IOp 2"} | Config];
+init_per_group(polling, Config) ->
+    case proplists:get_value(node_args, Config) of
+        undefined ->
+            Config;
+        Args ->
+            {ok, Node} = start_node(polling, Args),
+            [{node, Node} | Config]
+    end;
 init_per_group(_GroupName, Config) ->
     Config.
 
 end_per_group(_GroupName, Config) ->
+    case proplists:get_value(node, Config) of
+        undefined ->
+            ok;
+        Node ->
+            stop_node(Node)
+    end,
     Config.
 
 %% Test sending bad types to port with an outputv-capable driver.
@@ -778,21 +814,23 @@ io_ready_exit(Config) when is_list(Config) ->
 -define(CHKIO_STOP, 0).
 -define(CHKIO_USE_FALLBACK_POLLSET, 1).
 -define(CHKIO_BAD_FD_IN_POLLSET, 2).
--define(CHKIO_DRIVER_EVENT, 3).
 -define(CHKIO_FD_CHANGE, 4).
 -define(CHKIO_STEAL, 5).
 -define(CHKIO_STEAL_AUX, 6).
 -define(CHKIO_SMP_SELECT, 7).
 -define(CHKIO_DRV_USE, 8).
 
+use_fallback_pollset() ->
+    [{timetrap, {minutes, 2}}].
+
 use_fallback_pollset(Config) when is_list(Config) ->
+    rpc(Config, fun() -> use_fallback_pollset_t(Config) end).
+
+use_fallback_pollset_t(Config) when is_list(Config) ->
     FlbkFun = fun () ->
-                      ChkIoDuring = erlang:system_info(check_io),
-                      case lists:keysearch(fallback_poll_set_size,
-                                           1,
-                                           ChkIoDuring) of
-                          {value,
-                           {fallback_poll_set_size, N}} when N > 0 ->
+                      {Flbk, _} = get_fallback(erlang:system_info(check_io)),
+                      case lists:keysearch(total_poll_set_size, 1, Flbk) of
+                          {value, {total_poll_set_size, N}} when N > 0 ->
                               ok;
                           Error ->
                               ct:fail({failed_to_use_fallback, Error})
@@ -814,6 +852,7 @@ use_fallback_pollset(Config) when is_list(Config) ->
           Skip ->
               {fun () -> ok end, Skip, ok}
       end,
+    io:format("Node = ~p~n",[node()]),
     case chkio_test_fini(chkio_test(Handel,
                                     ?CHKIO_USE_FALLBACK_POLLSET,
                                     fun () ->
@@ -825,27 +864,31 @@ use_fallback_pollset(Config) when is_list(Config) ->
     end.
 
 bad_fd_in_pollset(Config) when is_list(Config) ->
-    chkio_test_fini(chkio_test(chkio_test_init(Config),
-                               ?CHKIO_BAD_FD_IN_POLLSET,
-                               fun () -> sleep(1000) end)).
-
-driver_event(Config) when is_list(Config) ->
-    chkio_test_fini(chkio_test(chkio_test_init(Config),
-                               ?CHKIO_DRIVER_EVENT,
-                               fun () -> sleep(1000) end)).
+    rpc(Config,
+        fun() ->
+                chkio_test_fini(chkio_test(chkio_test_init(Config),
+                                           ?CHKIO_BAD_FD_IN_POLLSET,
+                                           fun () -> sleep(1000) end))
+        end).
 
 fd_change(Config) when is_list(Config) ->
-    chkio_test_fini(chkio_test(chkio_test_init(Config),
-                               ?CHKIO_FD_CHANGE,
-                               fun () -> sleep(1000) end)).
+    rpc(Config,
+        fun() ->
+                chkio_test_fini(chkio_test(chkio_test_init(Config),
+                                           ?CHKIO_FD_CHANGE,
+                                           fun () -> sleep(1000) end))
+        end).
 
 steal_control(Config) when is_list(Config) ->
-    chkio_test_fini(case chkio_test_init(Config) of
-                        {erts_poll_info, _} = Hndl ->
-                            steal_control_test(Hndl);
-                        Skip ->
-                            Skip
-                    end).
+    rpc(Config,
+        fun() ->
+                chkio_test_fini(case chkio_test_init(Config) of
+                                    {erts_poll_info, _} = Hndl ->
+                                        steal_control_test(Hndl);
+                                    Skip ->
+                                        Skip
+                                end)
+        end).
 
 steal_control_test(Hndl = {erts_poll_info, Before}) ->
     Port = open_chkio_port(),
@@ -887,7 +930,7 @@ chkio_test_init(Config) when is_list(Config) ->
     ChkIo = get_stable_check_io_info(),
     case catch lists:keysearch(name, 1, ChkIo) of
         {value, {name, erts_poll}} ->
-            io:format("Before test: ~p~n", [ChkIo]),
+            ct:log("Before test: ~p~n", [ChkIo]),
             Path = proplists:get_value(data_dir, Config),
             erl_ddll:start(),
             ok = load_driver(Path, 'chkio_drv'),
@@ -948,8 +991,9 @@ chkio_test({erts_poll_info, Before},
         "ok" ->
             chk_chkio_port(Port),
             Fun(),
-            During = erlang:system_info(check_io),
+            During = get_check_io_total(erlang:system_info(check_io)),
             erlang:display(During),
+
             0 = element(1, erts_debug:get_internal_state(check_io_debug)),
             io:format("During test: ~p~n", [During]),
             chk_chkio_port(Port),
@@ -1001,22 +1045,83 @@ verify_chkio_state(Before, After) ->
     ok.
 
 get_stable_check_io_info() ->
-    ChkIo = erlang:system_info(check_io),
-    PendUpdNo = case lists:keysearch(pending_updates, 1, ChkIo) of
-                    {value, {pending_updates, PendNo}} ->
-                        PendNo;
-                    false ->
-                        0
-                end,
-    {value, {active_fds, ActFds}} = lists:keysearch(active_fds, 1, ChkIo),
+    get_stable_check_io_info(10).
+get_stable_check_io_info(0) ->
+    get_check_io_total(erlang:system_info(check_io));
+get_stable_check_io_info(N) ->
+    ChkIo = get_check_io_total(erlang:system_info(check_io)),
+    PendUpdNo = proplists:get_value(pending_updates, ChkIo, 0),
+    ActFds = proplists:get_value(active_fds, ChkIo),
     case {PendUpdNo, ActFds} of
         {0, 0} ->
             ChkIo;
         _ ->
-            receive after 10 -> ok end,
-            get_stable_check_io_info()
+            receive after 100 -> ok end,
+            get_stable_check_io_info(N-1)
     end.
 
+%% Merge return from erlang:system_info(check_io)
+%% as if it was one big pollset.
+get_check_io_total(ChkIo) ->
+    ct:log("ChkIo = ~p~n",[ChkIo]),
+    {Fallback, Rest} = get_fallback(ChkIo),
+    add_fallback_infos(Fallback,
+      lists:foldl(fun(Pollset, Acc) ->
+                          lists:zipwith(fun(A, B) ->
+                                                add_pollset_infos(A,B)
+                                        end,
+                                        Pollset, Acc)
+                  end,
+                  hd(Rest), tl(Rest))).
+
+add_pollset_infos({Tag, A}=TA , {Tag, B}=TB) ->
+    case tag_type(Tag) of
+        sum ->
+            {Tag, A + B};
+        const ->
+            case A of
+                B -> TA;
+                _ ->
+                    ct:fail("Unexpected diff in pollsets ~p != ~p",
+                            [TA,TB])
+            end
+    end.
+
+get_fallback([MaybeFallback | ChkIo] = AllChkIo) ->
+    case proplists:get_value(fallback, MaybeFallback) of
+        true ->
+            {MaybeFallback, ChkIo};
+        false ->
+            {undefined, AllChkIo}
+    end.
+
+add_fallback_infos(undefined, Acc) ->
+    Acc;
+add_fallback_infos(Flbk, Acc) ->
+    lists:zipwith(fun({Tag, A}=TA, {Tag, B}=TB) ->
+                          case tag_type(Tag) of
+                              sum -> {Tag, A + B};
+                              const when Tag =:= fallback -> TA;
+                              const -> TB
+                          end
+                  end,
+                  Flbk, Acc).
+
+tag_type(name) -> const;
+tag_type(primary) -> const;
+tag_type(fallback) -> const;
+tag_type(kernel_poll) -> const;
+tag_type(memory_size) -> sum;
+tag_type(total_poll_set_size) -> sum;
+tag_type(lazy_updates) -> const;
+tag_type(pending_updates) -> sum;
+tag_type(batch_updates) -> const;
+tag_type(concurrent_updates) -> const;
+tag_type(max_fds) -> const;
+tag_type(active_fds) -> sum;
+tag_type(poll_threads) -> sum.
+
+
 %% Missed port lock when stealing control of fd from a
 %% driver that didn't use the same lock. The lock checker
 %% used to trigger on this and dump core.
@@ -1087,9 +1192,9 @@ check_driver_system_info_result(Result) ->
     io:format("All names: ~p~n", [?EXPECTED_SYSTEM_INFO_NAMES]),
     io:format("Result: ~p~n", [Result]),
     {[], Ns, DDVSN} = chk_sis(lists:map(fun (Str) ->
-                                                string:tokens(Str, "=")
+                                                string:lexemes(Str, "=")
                                         end,
-                                        string:tokens(Result, " ")),
+                                        string:lexemes(Result, " ")),
                               ?EXPECTED_SYSTEM_INFO_NAMES),
     case {DDVSN,
           drv_vsn_str2tup(erlang:system_info(driver_version))} of
@@ -1144,8 +1249,6 @@ check_si_res(["thread", "false"]) ->
     false = erlang:system_info(threads);
 check_si_res(["smp", "true"]) ->
     true = erlang:system_info(smp_support);
-check_si_res(["smp", "false"]) ->
-    false = erlang:system_info(smp_support);
 
 %% Data added in second version of driver_system_info() (driver version 1.1)
 check_si_res(["async_thrs", Value]) ->
@@ -1338,11 +1441,9 @@ driver_monitor(Config) when is_list(Config) ->
 -define(IOQ_EXIT_READY_OUTPUT, 2).
 -define(IOQ_EXIT_TIMEOUT, 3).
 -define(IOQ_EXIT_READY_ASYNC, 4).
--define(IOQ_EXIT_EVENT, 5).
 -define(IOQ_EXIT_READY_INPUT_ASYNC, 6).
 -define(IOQ_EXIT_READY_OUTPUT_ASYNC, 7).
 -define(IOQ_EXIT_TIMEOUT_ASYNC, 8).
--define(IOQ_EXIT_EVENT_ASYNC, 9).
 
 ioq_exit_test(Config, TestNo) ->
     Drv = ioq_exit_drv,
@@ -1395,9 +1496,6 @@ ioq_exit_timeout(Config) when is_list(Config) ->
 ioq_exit_ready_async(Config) when is_list(Config) ->
     ioq_exit_test(Config, ?IOQ_EXIT_READY_ASYNC).
 
-ioq_exit_event(Config) when is_list(Config) ->
-    ioq_exit_test(Config, ?IOQ_EXIT_EVENT).
-
 ioq_exit_ready_input_async(Config) when is_list(Config) ->
     ioq_exit_test(Config, ?IOQ_EXIT_READY_INPUT_ASYNC).
 
@@ -1407,9 +1505,6 @@ ioq_exit_ready_output_async(Config) when is_list(Config) ->
 ioq_exit_timeout_async(Config) when is_list(Config) ->
     ioq_exit_test(Config, ?IOQ_EXIT_TIMEOUT_ASYNC).
 
-ioq_exit_event_async(Config) when is_list(Config) ->
-    ioq_exit_test(Config, ?IOQ_EXIT_EVENT_ASYNC).
-
 
 vsn_mismatch_test(Config, LoadResult) ->
     Path = proplists:get_value(data_dir, Config),
@@ -1643,7 +1738,7 @@ missing_callbacks(Config) when is_list(Config) ->
 smp_select(Config) when is_list(Config) -> 
     case os:type() of
         {win32,_} -> {skipped, "Test not implemented for this OS"};
-        _ -> smp_select0(Config)
+        _ -> rpc(Config, fun() -> smp_select0(Config) end)
     end.
 
 smp_select0(Config) ->
@@ -1699,7 +1794,7 @@ smp_select_wait(Pids, TimeoutMsg) ->
 driver_select_use(Config) when is_list(Config) -> 
     case os:type() of
         {win32,_} -> {skipped, "Test not implemented for this OS"};
-        _ -> driver_select_use0(Config)
+        _ -> rpc(Config, fun() -> driver_select_use0(Config) end)
     end.
 
 driver_select_use0(Config) ->
@@ -1944,44 +2039,39 @@ thr_msg_blast_receiver_proc(Port, Max, Parent, Done) ->
     end.
 
 thr_msg_blast(Config) when is_list(Config) ->
-    case erlang:system_info(smp_support) of
-        false ->
-            {skipped, "Non-SMP emulator; nothing to test..."};
-        true ->
-            Path = proplists:get_value(data_dir, Config),
-            erl_ddll:start(),
-            ok = load_driver(Path, thr_msg_blast_drv),
-            MemBefore = driver_alloc_size(),
-            Start = os:timestamp(),
-            Port = open_port({spawn, thr_msg_blast_drv}, []),
-            true = is_port(Port),
-            Done = make_ref(),
-            Me = self(),
-            spawn(fun () ->
-                          thr_msg_blast_receiver_proc(Port, 1, Me, Done)
-                  end),
-            receive
-                Done -> ok
-            end,
-            ok = thr_msg_blast_receiver(Port, 0, 32*10000),
-            port_close(Port),
-            End = os:timestamp(),
-            receive
-                Garbage ->
-                    ct:fail({received_garbage, Port, Garbage})
-            after 2000 ->
-                      ok
-            end,
-            MemAfter = driver_alloc_size(),
-            io:format("MemBefore=~p, MemAfter=~p~n",
-                      [MemBefore, MemAfter]),
-            ThrMsgBlastTime = timer:now_diff(End,Start)/1000000,
-            io:format("ThrMsgBlastTime=~p~n", [ThrMsgBlastTime]),
-            MemBefore = MemAfter,
-            Res = {thr_msg_blast_time, ThrMsgBlastTime},
-            erlang:display(Res),
-            Res
-    end.
+    Path = proplists:get_value(data_dir, Config),
+    erl_ddll:start(),
+    ok = load_driver(Path, thr_msg_blast_drv),
+    MemBefore = driver_alloc_size(),
+    Start = os:timestamp(),
+    Port = open_port({spawn, thr_msg_blast_drv}, []),
+    true = is_port(Port),
+    Done = make_ref(),
+    Me = self(),
+    spawn(fun () ->
+                  thr_msg_blast_receiver_proc(Port, 1, Me, Done)
+          end),
+    receive
+        Done -> ok
+    end,
+    ok = thr_msg_blast_receiver(Port, 0, 32*10000),
+    port_close(Port),
+    End = os:timestamp(),
+    receive
+        Garbage ->
+            ct:fail({received_garbage, Port, Garbage})
+    after 2000 ->
+            ok
+    end,
+    MemAfter = driver_alloc_size(),
+    io:format("MemBefore=~p, MemAfter=~p~n",
+              [MemBefore, MemAfter]),
+    ThrMsgBlastTime = timer:now_diff(End,Start)/1000000,
+    io:format("ThrMsgBlastTime=~p~n", [ThrMsgBlastTime]),
+    MemBefore = MemAfter,
+    Res = {thr_msg_blast_time, ThrMsgBlastTime},
+    erlang:display(Res),
+    Res.
 
 -define(IN_RANGE(LoW_, VaLuE_, HiGh_),
         case in_range(LoW_, VaLuE_, HiGh_) of
@@ -2271,10 +2361,10 @@ count_proc_sched(Ps, PNs) ->
     end.
 
 a_test(Config) when is_list(Config) ->
-    check_io_debug().
+    rpc(Config, fun check_io_debug/0).
 
 z_test(Config) when is_list(Config) ->
-    check_io_debug().
+    rpc(Config, fun check_io_debug/0).
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% 		Utilities
@@ -2282,8 +2372,8 @@ z_test(Config) when is_list(Config) ->
 
 check_io_debug() ->
     get_stable_check_io_info(),
-    {NoErrorFds, NoUsedFds, NoDrvSelStructs, NoDrvEvStructs} = CheckIoDebug
-    = erts_debug:get_internal_state(check_io_debug),
+    {NoErrorFds, NoUsedFds, NoDrvSelStructs, NoEnifSelStructs}
+        = CheckIoDebug = erts_debug:get_internal_state(check_io_debug),
     HasGetHost = has_gethost(),
     ct:log("check_io_debug: ~p~n"
            "HasGetHost: ~p",[CheckIoDebug, HasGetHost]),
@@ -2296,7 +2386,7 @@ check_io_debug() ->
             %% one extra used fd that is not selected on
             ok
     end,
-    0 = NoDrvEvStructs,
+    0 = NoEnifSelStructs,
     ok.
 
 has_gethost() ->
@@ -2348,7 +2438,7 @@ wait_until(Fun) ->
     end.
 
 drv_vsn_str2tup(Str) ->
-    [Major, Minor] = string:tokens(Str, "."),
+    [Major, Minor] = string:lexemes(Str, "."),
     {list_to_integer(Major), list_to_integer(Minor)}.
 
 %% Build port data from a template.
@@ -2466,15 +2556,19 @@ sleep(Ms) when is_integer(Ms), Ms >= 0 ->
 
 
 start_node(Config) when is_list(Config) ->
+    start_node(proplists:get_value(testcase, Config));
+start_node(Name) ->
+    start_node(Name, "").
+start_node(NodeName, Args) ->
     Pa = filename:dirname(code:which(?MODULE)),
     Name = list_to_atom(atom_to_list(?MODULE)
                         ++ "-"
-                        ++ atom_to_list(proplists:get_value(testcase, Config))
+                        ++ atom_to_list(NodeName)
                         ++ "-"
                         ++ integer_to_list(erlang:system_time(second))
                         ++ "-"
                         ++ integer_to_list(erlang:unique_integer([positive]))),
-    test_server:start_node(Name, slave, [{args, "-pa "++Pa}]).
+    test_server:start_node(Name, slave, [{args, Args ++ " -pa "++Pa}]).
 
 stop_node(Node) ->
     test_server:stop_node(Node).
@@ -2488,14 +2582,6 @@ wait_deallocations() ->
     end.
 
 driver_alloc_size() ->
-    case erlang:system_info(smp_support) of
-        true ->
-            ok;
-        false ->
-            %% driver_alloc also used by elements in lock-free queues,
-            %% give these some time to be deallocated...
-            receive after 100 -> ok end
-    end,
     wait_deallocations(),
     case erlang:system_info({allocator_sizes, driver_alloc}) of
         false ->
@@ -2515,3 +2601,35 @@ driver_alloc_size() ->
                       Sz0+Sz
               end, 0, CS)
     end.
+
+rpc(Config, Fun) ->
+    case proplists:get_value(node, Config) of
+        undefined ->
+            Fun();
+        Node ->
+            Self = self(),
+            Ref = make_ref(),
+            Pid = spawn(Node,
+                        fun() ->
+                                Result
+                                    = try Fun() of
+                                          Res -> Res
+                                      catch E:R:Stk ->
+                                              {'EXIT',E,R,Stk}
+                                      end,
+                                Self ! {Ref, Result}
+                        end),
+            MRef = monitor(process, Pid),
+            receive
+                {'DOWN', MRef, _Type, _Object, Info} ->
+                    erlang:error({died, Pid, Info});
+                {Ref, {'EXIT',E,R,ST}} ->
+                    erlang:demonitor(MRef, [flush]),
+                    erlang:raise(E,R,ST);
+                {Ref, Ret} ->
+                    erlang:demonitor(MRef, [flush]),
+                    Ret;
+                Other ->
+                    ct:fail(Other)
+            end
+    end.
diff --git a/erts/emulator/test/driver_SUITE_data/chkio_drv.c b/erts/emulator/test/driver_SUITE_data/chkio_drv.c
index 8e5e81665c..d548c4b1dc 100644
--- a/erts/emulator/test/driver_SUITE_data/chkio_drv.c
+++ b/erts/emulator/test/driver_SUITE_data/chkio_drv.c
@@ -42,7 +42,6 @@
 #define CHKIO_STOP				0
 #define CHKIO_USE_FALLBACK_POLLSET		1
 #define CHKIO_BAD_FD_IN_POLLSET			2
-#define CHKIO_DRIVER_EVENT			3
 #define CHKIO_FD_CHANGE				4
 #define CHKIO_STEAL				5
 #define CHKIO_STEAL_AUX				6
@@ -67,15 +66,6 @@ typedef struct {
 } ChkioFallbackData;
 
 typedef struct {
-    int in_fd;
-    struct erl_drv_event_data in_data;
-    int in_ok;
-    int out_fd;
-    struct erl_drv_event_data out_data;
-    int out_ok;
-} ChkioDriverEvent;
-
-typedef struct {
     int fds[2];
     int same_fd;
 } ChkioFdChange;
@@ -86,14 +76,10 @@ typedef struct {
 
 typedef struct {
     int driver_select_fds[2];
-    int driver_event_fds[2];
-    struct erl_drv_event_data event_data[2];
 } ChkioSteal;
 
 typedef struct {
     int driver_select_fds[2];
-    int driver_event_fds[2];
-    struct erl_drv_event_data event_data[2];
 } ChkioStealAux;
 
 
@@ -141,7 +127,6 @@ static ErlDrvData chkio_drv_start(ErlDrvPort, char *);
 static void chkio_drv_stop(ErlDrvData);
 static void chkio_drv_ready_input(ErlDrvData, ErlDrvEvent);
 static void chkio_drv_ready_output(ErlDrvData, ErlDrvEvent);
-static void chkio_drv_ready_event(ErlDrvData, ErlDrvEvent, ErlDrvEventData);
 static ErlDrvSSizeT chkio_drv_control(ErlDrvData, unsigned int,
 				      char *, ErlDrvSizeT, char **, ErlDrvSizeT);
 static void chkio_drv_timeout(ErlDrvData);
@@ -164,7 +149,7 @@ static ErlDrvEntry chkio_drv_entry = {
     NULL, /* ready_async */
     NULL, /* flush */
     NULL, /* call */
-    chkio_drv_ready_event,
+    NULL, /* unused_event_callback */
 
     ERL_DRV_EXTENDED_MARKER,
     ERL_DRV_EXTENDED_MAJOR_VERSION,
@@ -243,25 +228,6 @@ stop_use_fallback_pollset(ChkioDrvData *cddp)
 }
 
 static void
-stop_driver_event(ChkioDrvData *cddp)
-{
-    if (cddp->test_data) {
-	ChkioDriverEvent *cdep = cddp->test_data;
-	cddp->test_data = NULL;
-
-	if (cdep->in_fd >= 0) {
-	    driver_event(cddp->port, (ErlDrvEvent) (ErlDrvSInt) cdep->in_fd, NULL);
-	    close(cdep->in_fd);
-	}
-	if (cdep->out_fd >= 0) {
-	    driver_event(cddp->port, (ErlDrvEvent) (ErlDrvSInt) cdep->out_fd, NULL);
-	    close(cdep->out_fd);
-	}
-	driver_free(cdep);	    
-    }
-}
-
-static void
 stop_fd_change(ChkioDrvData *cddp)
 {
     if (cddp->test_data) {
@@ -305,14 +271,6 @@ stop_steal(ChkioDrvData *cddp)
 			  (ErlDrvEvent) (ErlDrvSInt) csp->driver_select_fds[1],
 			  DO_WRITE,
 			  0);
-	if (csp->driver_event_fds[0] >= 0)
-	    driver_event(cddp->port,
-			 (ErlDrvEvent) (ErlDrvSInt) csp->driver_event_fds[0],
-			 NULL);
-	if (csp->driver_event_fds[1] >= 0)
-	    driver_event(cddp->port,
-			 (ErlDrvEvent) (ErlDrvSInt) csp->driver_event_fds[1],
-			 NULL);
 	driver_free(csp);
     }
 }
@@ -327,10 +285,6 @@ stop_steal_aux(ChkioDrvData *cddp)
 	    close(csap->driver_select_fds[0]);
 	if (csap->driver_select_fds[1] >= 0)
 	    close(csap->driver_select_fds[1]);
-	if (csap->driver_event_fds[0] >= 0)
-	    close(csap->driver_event_fds[0]);
-	if (csap->driver_event_fds[1] >= 0)
-	    close(csap->driver_event_fds[1]);
 	driver_free(csap);
     }
 }
@@ -354,10 +308,13 @@ static void free_smp_select(ChkioSmpSelect* pip, ErlDrvPort port)
 	abort();
     }
     case Selected:
-	driver_select(port, (ErlDrvEvent)(ErlDrvSInt)pip->read_fd, DO_READ, 0);
-	/*fall through*/ 
     case Opened:
-	close(pip->read_fd);
+        TRACEF(("%T: Close pipe [%d->%d]\n", driver_mk_port(port), pip->write_fd,
+                pip->read_fd));
+        if (pip->wasSelected)
+            driver_select(port, (ErlDrvEvent)(ErlDrvSInt)pip->read_fd, DO_READ|ERL_DRV_USE, 0);
+        else
+            close(pip->read_fd);
 	close(pip->write_fd);
 	pip->state = Closed;
 	break;
@@ -445,9 +402,6 @@ chkio_drv_stop(ErlDrvData drv_data) {
     case CHKIO_BAD_FD_IN_POLLSET:
 	stop_bad_fd_in_pollset(cddp);
 	break;
-    case CHKIO_DRIVER_EVENT:
-	stop_driver_event(cddp);
-	break;
     case CHKIO_FD_CHANGE:
 	stop_fd_change(cddp);
 	break;
@@ -557,6 +511,9 @@ chkio_drv_ready_input(ErlDrvData drv_data, ErlDrvEvent event)
 	    driver_failure_atom(cddp->port, "input_fd_not_found");
 	break;
     }
+    case CHKIO_FD_CHANGE:
+        /* This may be triggered when an fd is closed while being selected on. */
+        break;
     case CHKIO_STEAL:
 	break;
     case CHKIO_STEAL_AUX:
@@ -621,55 +578,6 @@ chkio_drv_ready_input(ErlDrvData drv_data, ErlDrvEvent event)
 }
 
 static void
-chkio_drv_ready_event(ErlDrvData drv_data,
-		      ErlDrvEvent event,
-		      ErlDrvEventData event_data)
-{
-#ifdef UNIX
-    ChkioDrvData *cddp = (ChkioDrvData *) drv_data;
-    switch (cddp->test) {
-    case CHKIO_DRIVER_EVENT: {
-#ifdef HAVE_POLL_H
-	ChkioDriverEvent *cdep = cddp->test_data;
-	int fd = (int) (ErlDrvSInt) event;
-	if (fd == cdep->in_fd) {
-	    if (event_data->events == POLLIN
-		&& event_data->revents == POLLIN) {
-		cdep->in_ok++;
-	    }
-	    else {
-		driver_failure_atom(cddp->port, "invalid_input_fd_events");
-	    }
-	    break;
-	}
-	if (fd == cdep->out_fd) {
-	    if (event_data->events == POLLOUT
-		&& event_data->revents == POLLOUT) {
-		cdep->out_ok++;
-	    }
-	    else {
-		driver_failure_atom(cddp->port, "invalid_output_fd_events");
-	    }
-	    break;
-	}
-#endif
-    }
-    case CHKIO_STEAL:
-#ifdef HAVE_POLL_H
-	break;
-#endif
-    case CHKIO_STEAL_AUX:
-#ifdef HAVE_POLL_H
-	break;
-#endif
-    default:
-	driver_failure_atom(cddp->port, "unexpected_ready_event");
-	break;
-    }
-#endif /* UNIX */
-}
-
-static void
 chkio_drv_timeout(ErlDrvData drv_data)
 {
 #ifdef UNIX
@@ -779,25 +687,6 @@ chkio_drv_control(ErlDrvData drv_data,
 	    res_len = -1;
 	    stop_bad_fd_in_pollset(cddp);
 	    break;
-	case CHKIO_DRIVER_EVENT: {
-	    ChkioDriverEvent *cdep = cddp->test_data;
-	    if (!cdep->in_ok || !cdep->out_ok) {
-		if (!cdep->in_ok)
-		    driver_failure_atom(cddp->port, "got_no_input_events");
-		if (!cdep->out_ok)
-		    driver_failure_atom(cddp->port, "got_no_output_events");
-	    }
-	    else {
-		char *c = driver_alloc(sizeof(char)*2*30);
-		if (!c)
-		    driver_failure_posix(cddp->port, ENOMEM);
-		*rbuf = c;
-		res_len = sprintf(c, "in=%d\nout=%d\n",
-				  cdep->in_ok, cdep->out_ok);
-	    }
-	    stop_driver_event(cddp);
-	    break;
-	}
 	case CHKIO_FD_CHANGE: {
 	    ChkioFdChange *cfcp = cddp->test_data;
 	    if (!cfcp->same_fd)
@@ -937,69 +826,6 @@ chkio_drv_control(ErlDrvData drv_data,
 	res_len = -1;
 	break;
     }
-    case CHKIO_DRIVER_EVENT: {
-#ifndef HAVE_POLL_H
-	res_str = "skip: Need the poll.h header for this test, but it doesn't exist";
-	res_len = -1;
-#else /* HAVE_POLL_H */
-	int in_fd = open("/dev/zero", O_RDONLY);
-	int out_fd = open("/dev/null", O_WRONLY);
-
-	if (in_fd < 0 || out_fd < 0) {
-	    if (in_fd >= 0)
-		close(in_fd);
-	    if (out_fd >= 0)
-		close(out_fd);
-	    driver_failure_posix(cddp->port, errno);
-	}
-	else {
-	    ChkioDriverEvent *cdep = driver_alloc(sizeof(ChkioDriverEvent));
-	    if (!cdep)
-		driver_failure_posix(cddp->port, ENOMEM);
-	    else {
-		int res;
-		cddp->test_data = cdep;
-
-		cdep->in_fd = in_fd;
-		cdep->in_data.events = POLLIN;
-		cdep->in_data.revents = 0;
-		cdep->in_ok = 0;
-
-		res = driver_event(cddp->port,
-				   (ErlDrvEvent) (ErlDrvSInt) in_fd,
-				   &cdep->in_data);
-		if (res < 0) {
-		    res_str = "skip: driver_event() not supported";
-		    res_len = -1;
-		    close(in_fd);
-		    close(out_fd);
-		    cdep->in_fd = -1;
-		    cdep->out_fd = -1;
-		}
-		else {
-		    res_str = "ok";
-		    res_len = -1;
-
-		    cdep->out_fd = out_fd;
-		    cdep->out_data.events = POLLOUT;
-		    cdep->out_data.revents = 0;
-		    cdep->out_ok = 0;
-
-		    res = driver_event(cddp->port,
-				       (ErlDrvEvent) (ErlDrvSInt) out_fd,
-				       &cdep->out_data);
-		    if (res < 0) {
-			close(out_fd);
-			cdep->out_fd = -1;
-			driver_failure_atom(cddp->port, "driver_event_failed");
-		    }
-		}
-
-	    }
-	}
-#endif /* HAVE_POLL_H */
-	break;
-    }
     case CHKIO_FD_CHANGE: {
 	ChkioFdChange *cfcp = driver_alloc(sizeof(ChkioFdChange));
 	if (!cfcp)
@@ -1028,58 +854,19 @@ chkio_drv_control(ErlDrvData drv_data,
 	    res_len = -1;
 	}
 	else {
-	    int driver_event_fds[2];
 	    int driver_select_fds[2];
 	    cddp->test_data = csp; 
 	    memcpy(c, buf, len);
 	    c[len] = '\0';
 	    if (sscanf(c,
-		       "fds:%d:%d:%d:%d",
+		       "fds:%d:%d",
 		       &driver_select_fds[0],
-		       &driver_select_fds[1],
-		       &driver_event_fds[0],
-		       &driver_event_fds[1]) != 4)
-		driver_failure_atom(cddp->port, "bad_input");
+		       &driver_select_fds[1]) != 2)
+                driver_failure_atom(cddp->port, "bad_input");
 	    else {
 		int res = 0;
-		if (driver_event_fds[0] < 0) { /* Have no working driver_event() ... */
-		    csp->driver_select_fds[0] = driver_select_fds[0]; /* In */
-		    csp->driver_select_fds[1] = driver_select_fds[1]; /* Out */
-		    csp->driver_event_fds[0] = -1;
-		    csp->driver_event_fds[1] = -1;
-		}
-		else { /* Have working driver_event() ... */
-#ifndef HAVE_POLL_H
-		    driver_failure_atom(cddp->port, "unexpected_result");
-		    res = -1;
-#else
-		    csp->driver_select_fds[0] = driver_select_fds[0]; /* In */
-		    csp->driver_event_fds[1] = driver_select_fds[1]; /* Out */
-		    csp->driver_event_fds[0] = driver_event_fds[0]; /* In */
-		    csp->driver_select_fds[1] = driver_event_fds[1]; /* Out */
-
-		    /* Steal with driver_event() */
-
-		    csp->event_data[0].events = POLLIN;
-		    csp->event_data[0].revents = 0;
-		    res = driver_event(cddp->port,
-				       (ErlDrvEvent) (ErlDrvSInt) csp->driver_event_fds[0],
-				       &csp->event_data[0]);
-		    if (res < 0)
-			driver_failure_atom(cddp->port,
-					    "driver_event_failed_to_steal");
-		    if (res >= 0) {
-			csp->event_data[1].events = POLLOUT;
-			csp->event_data[1].revents = 0;
-			res = driver_event(cddp->port,
-					   (ErlDrvEvent) (ErlDrvSInt) csp->driver_event_fds[1],
-					   &csp->event_data[1]);
-			if (res < 0)
-			    driver_failure_atom(cddp->port,
-						"driver_event_failed_to_steal");
-		    }
-#endif
-		}
+                csp->driver_select_fds[0] = driver_select_fds[0]; /* In */
+                csp->driver_select_fds[1] = driver_select_fds[1]; /* Out */
 
 		/* Steal with driver_select() */
 		if (res >= 0) {
@@ -1109,37 +896,17 @@ chkio_drv_control(ErlDrvData drv_data,
 	break;
     }
     case CHKIO_STEAL_AUX: {
-	int read_fds[2];
-	int write_fds[2];
+	int read_fd;
+	int write_fd;
 
-	read_fds[0] = open("/dev/zero", O_RDONLY);
-	write_fds[0] = open("/dev/null", O_WRONLY);
-
-#ifdef HAVE_POLL_H
-	read_fds[1] = open("/dev/zero", O_RDONLY);
-	write_fds[1] = open("/dev/null", O_WRONLY);
-#else
-	read_fds[1] = -1;
-	write_fds[1] = -1;
-#endif
+	read_fd = open("/dev/zero", O_RDONLY);
+	write_fd = open("/dev/null", O_WRONLY);
 	
-	if (read_fds[0] < 0
-	    || write_fds[0] < 0
-#ifdef HAVE_POLL_H
-	    || read_fds[1] < 0 
-	    || write_fds[1] < 0
-#endif
-	    ) {
-	    if (read_fds[0] < 0)
-		close(read_fds[0]);
-	    if (write_fds[0] < 0)
-		close(write_fds[0]);
-#ifdef HAVE_POLL_H
-	    if (read_fds[1] < 0)
-		close(read_fds[1]);
-	    if (write_fds[1] < 0)
-		close(write_fds[1]);
-#endif
+	if (read_fd < 0 || write_fd < 0) {
+	    if (read_fd < 0)
+		close(read_fd);
+	    if (write_fd < 0)
+		close(write_fd);
 	    driver_failure_posix(cddp->port, errno);
 	}
 	else {
@@ -1153,11 +920,8 @@ chkio_drv_control(ErlDrvData drv_data,
 		int res;
 		cddp->test_data = csap;
 
-		csap->driver_select_fds[0] = read_fds[0];
-		csap->driver_select_fds[1] = write_fds[0];
-
-		csap->driver_event_fds[0] = read_fds[1];
-		csap->driver_event_fds[1] = write_fds[1];
+		csap->driver_select_fds[0] = read_fd;
+		csap->driver_select_fds[1] = write_fd;
 
 		res = driver_select(cddp->port,
 				    (ErlDrvEvent) (ErlDrvSInt) csap->driver_select_fds[0],
@@ -1173,32 +937,6 @@ chkio_drv_control(ErlDrvData drv_data,
 		    if (res < 0)
 			driver_failure_atom(cddp->port, "driver_select_failed");
 		}
-#ifdef HAVE_POLL_H
-		if (res >= 0) {
-		    csap->event_data[0].events = POLLIN;
-		    csap->event_data[0].revents = 0;
-		    res = driver_event(cddp->port,
-				       (ErlDrvEvent) (ErlDrvSInt) csap->driver_event_fds[0],
-				       &csap->event_data[0]);
-		    if (res < 0) {
-			close(csap->driver_event_fds[0]);
-			csap->driver_event_fds[0] = -1;
-			close(csap->driver_event_fds[1]);
-			csap->driver_event_fds[1] = -1;
-			res = 0;
-		    }
-		    else {
-			csap->event_data[1].events = POLLOUT;
-			csap->event_data[1].revents = 0;
-			res = driver_event(cddp->port,
-					   (ErlDrvEvent) (ErlDrvSInt) csap->driver_event_fds[1],
-					   &csap->event_data[1]);
-			if (res < 0)
-			    driver_failure_atom(cddp->port,
-						"driver_event_failed");
-		    }
-		}
-#endif
 		if (res < 0) {
 		    res_str = "error";
 		    res_len = -1;
@@ -1213,11 +951,9 @@ chkio_drv_control(ErlDrvData drv_data,
 		    else {
 			*rbuf = c;
 			res_len = sprintf(c,
-					  "fds:%d:%d:%d:%d",
+					  "fds:%d:%d",
 					  csap->driver_select_fds[0],
-					  csap->driver_select_fds[1],
-					  csap->driver_event_fds[0],
-					  csap->driver_event_fds[1]);
+					  csap->driver_select_fds[1]);
 		    }
 		}
 	    }
@@ -1257,7 +993,7 @@ chkio_drv_control(ErlDrvData drv_data,
 		}
 		TRACEF(("%T: Created pipe [%d->%d]\n", cddp->id, fds[1], fds[0]));
 		pip->read_fd = fds[0];
-		pip->write_fd = fds[1];	       
+		pip->write_fd = fds[1];
 		pip->state = Opened;
 		pip->wasSelected = 0;
 		pip->next_write = pip->next_read = rand_r(&pip->rand_state) % 1024;
@@ -1267,7 +1003,8 @@ chkio_drv_control(ErlDrvData drv_data,
 	    }/*fall through*/
 	    case Opened: {
 		if (op & 1) {
-		    TRACEF(("%T: Write %d to opened pipe [%d->%d]\n", cddp->id, pip->next_write, pip->write_fd, pip->read_fd));
+		    TRACEF(("%T: Write %d to opened pipe [%d->%d]\n", cddp->id,
+                            pip->next_write, pip->write_fd, pip->read_fd));
 		    if (write(pip->write_fd, &pip->next_write, sizeof(int)) != sizeof(int)) {
 			fprintf(stderr, "Failed to write to pipe fd=%d, errno=%d\n", pip->write_fd, errno);
 			abort();
@@ -1276,8 +1013,12 @@ chkio_drv_control(ErlDrvData drv_data,
 		}
 		op >>= 1;
 		if (pip->wasSelected && (op & 1)) {
-		    TRACEF(("%T: Close pipe [%d->%d]\n", cddp->id, pip->write_fd, pip->read_fd));
-		    if (close(pip->read_fd) || close(pip->write_fd)) {
+		    TRACEF(("%T: Close pipe [%d->%d]\n", cddp->id, pip->write_fd,
+                            pip->read_fd));
+                    drv_use_singleton.fd_stop_select = -2; /* disable stop_select asserts */
+		    if (driver_select(cddp->port, (ErlDrvEvent)(ErlDrvSInt)pip->read_fd,
+                                      DO_READ|ERL_DRV_USE, 0)
+                        || close(pip->write_fd)) {
 			fprintf(stderr, "Failed to close pipe, errno=%d\n", errno);
 			abort();
 		    }
@@ -1285,8 +1026,10 @@ chkio_drv_control(ErlDrvData drv_data,
 		    break;
 		}
 		else {
-		    TRACEF(("%T: Select on pipe [%d->%d]\n", cddp->id, pip->write_fd, pip->read_fd));
-		    if (driver_select(cddp->port, (ErlDrvEvent)(ErlDrvSInt)pip->read_fd, DO_READ, 1)) {
+		    TRACEF(("%T: Select on pipe [%d->%d]\n", cddp->id,
+                            pip->write_fd, pip->read_fd));
+		    if (driver_select(cddp->port, (ErlDrvEvent)(ErlDrvSInt)pip->read_fd,
+                                      DO_READ|ERL_DRV_USE, 1)) {
 			fprintf(stderr, "driver_select failed for fd=%d\n", pip->read_fd);
 			abort();
 		    }
@@ -1294,13 +1037,13 @@ chkio_drv_control(ErlDrvData drv_data,
 		    pip->wasSelected = 1;
 		    op >>= 1;
 		    if (pip->next_write != pip->next_read) { /* pipe not empty */
-			if (op & 1) {  
+			if (op & 1) {
 			    pip->state = Waiting; /* Wait for reader */
 			    break;
 			}
 			op >>= 1;
 		    }
-		}  
+		}
 	    }/*fall through*/
 	    case Selected:
 		if (op & 1) {
@@ -1329,7 +1072,7 @@ chkio_drv_control(ErlDrvData drv_data,
 			fprintf(stderr, "Failed to write to pipe fd=%d, errno=%d\n", pip->write_fd, errno);
 			abort();
 		    }
-		    pip->next_write++;		    
+		    pip->next_write++;
 		}
 		break;
 	    case Waiting:
@@ -1583,7 +1326,12 @@ static void chkio_drv_stop_select(ErlDrvEvent e, void* null)
     if (!(drv_use_singleton.fd_stop_select < 0)) {
 	assert_print("fd_stop_select<0", __LINE__); abort(); 
     }
-    drv_use_singleton.fd_stop_select = (int)(long)e;
+    /* fd_stop_select counting is disabled if this is set to -2 */
+    if (drv_use_singleton.fd_stop_select == -2) {
+        TRACEF(("closing %d\n", (int)(long)e));
+        close((int)(long)e);
+    } else
+        drv_use_singleton.fd_stop_select = (int)(long)e;
     /* Can't call chkio_drv_use directly here. That could even be recursive.
      * Next timeout will detect it instead.
      */
diff --git a/erts/emulator/test/driver_SUITE_data/ioq_exit_drv.c b/erts/emulator/test/driver_SUITE_data/ioq_exit_drv.c
index d87c2bec93..fa58e9d5ec 100644
--- a/erts/emulator/test/driver_SUITE_data/ioq_exit_drv.c
+++ b/erts/emulator/test/driver_SUITE_data/ioq_exit_drv.c
@@ -25,8 +25,7 @@
  *		- ready_input(),
  *		- ready_output(),
  *		- timeout(),
- *		- driver_async() -> read_async(), and
- *		- event()
+ *		- driver_async() -> read_async()
  */
 
 #ifndef UNIX
@@ -65,11 +64,9 @@ typedef enum {
     IOQ_EXIT_READY_OUTPUT = 2,
     IOQ_EXIT_TIMEOUT = 3,
     IOQ_EXIT_READY_ASYNC = 4,
-    IOQ_EXIT_EVENT = 5,
     IOQ_EXIT_READY_INPUT_ASYNC = 6,
     IOQ_EXIT_READY_OUTPUT_ASYNC = 7,
     IOQ_EXIT_TIMEOUT_ASYNC = 8,
-    IOQ_EXIT_EVENT_ASYNC = 9
 } IOQExitTest;
 
 typedef struct {
@@ -80,9 +77,6 @@ typedef struct {
     int outstanding_async_task;
     long async_task;
     ErlDrvPDL pdl;
-#ifdef HAVE_POLL_H
-    struct erl_drv_event_data event_data;
-#endif
 } IOQExitDrvData;
 
 #define EV2FD(EV) ((int) ((long) (EV)))
@@ -97,8 +91,6 @@ static ErlDrvSSizeT control(ErlDrvData, unsigned int,
 static void timeout(ErlDrvData drv_data);
 static void ready_async(ErlDrvData drv_data, ErlDrvThreadData thread_data);
 static void flush(ErlDrvData drv_data);
-static void event(ErlDrvData drv_data, ErlDrvEvent event,
-		  ErlDrvEventData event_data);
 static void async_invoke(void*);
 static void do_driver_async(IOQExitDrvData *);
 
@@ -118,7 +110,7 @@ static ErlDrvEntry ioq_exit_drv_entry = {
     ready_async,
     flush,
     NULL /* call */,
-    event,
+    NULL /* unused_event_callback*/,
     ERL_DRV_EXTENDED_MARKER,
     ERL_DRV_EXTENDED_MAJOR_VERSION,
     ERL_DRV_EXTENDED_MINOR_VERSION,
@@ -149,10 +141,6 @@ start(ErlDrvPort port, char *command)
     ddp->outstanding_async_task = 0;
     ddp->async_task = -1;
     ddp->pdl = driver_pdl_create(port);
-#ifdef HAVE_POLL_H
-    ddp->event_data.events = (short) 0;
-    ddp->event_data.revents = (short) 0;
-#endif
 
     return (ErlDrvData) ddp;
 }
@@ -192,27 +180,6 @@ static ErlDrvSSizeT control(ErlDrvData drv_data,
 #else
 	goto done;
 #endif
-    case IOQ_EXIT_EVENT:
-    case IOQ_EXIT_EVENT_ASYNC:
-#ifdef UNIX
-#ifdef HAVE_POLL_H
-	ddp->ofd = open("/dev/null", O_WRONLY);
-	if (ddp->ofd < 0) {
-	    driver_failure_posix(ddp->port, errno);
-	    return 0;
-	}
-	else if (driver_event(ddp->port, FD2EV(ddp->ofd), NULL) != 0) {
-	    res_str = "skip: driver_event() not supported";
-	    goto done;
-	}
-#else
-	res_str = "skip: No poll.h found which is needed for this test";
-	goto done;
-#endif
-	break;
-#else /* UNIX */
-	goto done;
-#endif
     case IOQ_EXIT_TIMEOUT:
     case IOQ_EXIT_TIMEOUT_ASYNC:
 	break;
@@ -266,13 +233,6 @@ static void stop(ErlDrvData drv_data)
 		close(ddp->ofd);
 	    }
 	    break;
-	case IOQ_EXIT_EVENT:
-	case IOQ_EXIT_EVENT_ASYNC:
-	    if (ddp->ofd >= 0) {
-		driver_event(ddp->port, FD2EV(ddp->ofd), NULL);
-		close(ddp->ofd);
-	    }
-	    break;
 #endif
 	case IOQ_EXIT_TIMEOUT:
 	case IOQ_EXIT_TIMEOUT_ASYNC:
@@ -302,13 +262,6 @@ static void flush(ErlDrvData drv_data)
     case IOQ_EXIT_READY_OUTPUT_ASYNC:
 	driver_select(ddp->port, FD2EV(ddp->ofd), DO_WRITE, 1);
 	break;
-    case IOQ_EXIT_EVENT:
-    case IOQ_EXIT_EVENT_ASYNC:
-#ifdef HAVE_POLL_H
-	ddp->event_data.events |= POLLOUT;
-	driver_event(ddp->port, FD2EV(ddp->ofd), &ddp->event_data);
-#endif
-	break;
 #endif
     case IOQ_EXIT_TIMEOUT:
     case IOQ_EXIT_TIMEOUT_ASYNC:
@@ -395,30 +348,6 @@ static void ready_async(ErlDrvData drv_data, ErlDrvThreadData thread_data)
     }
 }
 
-static void event(ErlDrvData drv_data,
-		  ErlDrvEvent event,
-		  ErlDrvEventData event_data)
-{
-    IOQExitDrvData *ddp = (IOQExitDrvData *) drv_data;
-
-    PRINTF(("event(%p, %d, %p) called\r\n", drv_data, EV2FD(event), event_data));
-
-#if defined(UNIX) && defined(HAVE_POLL_H)
-    if (ddp->ofd == EV2FD(event)) {
-	driver_event(ddp->port, FD2EV(ddp->ofd), NULL);
-	close(ddp->ofd);
-	ddp->ofd = -1;
-	if (ddp->test == IOQ_EXIT_EVENT_ASYNC)
-	    do_driver_async(ddp);
-	else {
-	    driver_pdl_lock(ddp->pdl);
-	    driver_deq(ddp->port, 1);
-	    driver_pdl_unlock(ddp->pdl);
-	}
-    }
-#endif
-}
-
 static void async_invoke(void *arg)
 {
     PRINTF(("async_invoke(%p) called\r\n", arg));
diff --git a/erts/emulator/test/driver_SUITE_data/missing_callback_drv.c b/erts/emulator/test/driver_SUITE_data/missing_callback_drv.c
index e7480d2e00..14838f0377 100644
--- a/erts/emulator/test/driver_SUITE_data/missing_callback_drv.c
+++ b/erts/emulator/test/driver_SUITE_data/missing_callback_drv.c
@@ -41,10 +41,6 @@
 typedef struct {
     int ofd;
     int ifd;
-    int efd;
-#ifdef HAVE_POLL_H
-    struct erl_drv_event_data edata;
-#endif
 } mcd_data_t;
 
 static ErlDrvData start(ErlDrvPort port, char *command);
@@ -90,7 +86,6 @@ start(ErlDrvPort port, char *command)
 
     mcd->ofd = -1;
     mcd->ifd = -1;
-    mcd->efd = -1;
 
 #ifdef UNIX
 
@@ -105,15 +100,6 @@ start(ErlDrvPort port, char *command)
 	goto error;
     if (driver_select(port, (ErlDrvEvent) (long) mcd->ifd, DO_READ, 1) != 0)
 	goto error;
-
-#ifdef HAVE_POLL_H
-    mcd->efd = open("/dev/null", O_WRONLY);
-    if (mcd->efd < 0)
-	goto error;
-    mcd->edata.events = POLLOUT;
-    mcd->edata.revents = 0;
-    driver_event(port, (ErlDrvEvent) (long) mcd->efd, &mcd->edata);
-#endif
 #endif
 
     driver_set_timer(port, 0);
@@ -135,10 +121,6 @@ stop(ErlDrvData data)
 	    close(mcd->ofd);
 	if (mcd->ifd >= 0)
 	    close(mcd->ifd);
-#ifdef HAVE_POLL_H
-	if (mcd->efd >= 0)
-	    close(mcd->efd);
-#endif
 #endif
 	driver_free(mcd);
     }
diff --git a/erts/emulator/test/dump_SUITE.erl b/erts/emulator/test/dump_SUITE.erl
new file mode 100644
index 0000000000..38fa198ea6
--- /dev/null
+++ b/erts/emulator/test/dump_SUITE.erl
@@ -0,0 +1,125 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2005-2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+
+-module(dump_SUITE).
+
+-include_lib("common_test/include/ct.hrl").
+
+-export([all/0, suite/0, init_per_testcase/2, end_per_testcase/2]).
+
+-export([signal_abort/1]).
+
+-export([load/0]).
+
+-include_lib("kernel/include/file.hrl").
+
+suite() ->
+    [{ct_hooks,[ts_install_cth]},
+     {timetrap, {minutes, 2}}].
+
+all() ->
+    [signal_abort].
+
+init_per_testcase(signal_abort, Config) ->
+    SO = erlang:system_info(schedulers_online),
+    erts_debug:set_internal_state(available_internal_state, true),
+    Dump = erts_debug:get_internal_state(scheduler_dump),
+    erts_debug:set_internal_state(available_internal_state, false),
+    if SO < 3 ->
+            {skip, "not enough schedulers"};
+       not Dump ->
+            {skip, "the platform does not support scheduler dump"};
+       Dump ->
+            Config
+    end.
+
+end_per_testcase(_, Config) ->
+    Config.
+
+%%%
+%%% The test cases -------------------------------------------------------------
+%%%
+
+%% Test that a snapshot is taken of other schedulers using a signal
+%% when a crash dump is generated.
+signal_abort(Config) ->
+
+    Dump = filename:join(proplists:get_value(priv_dir, Config),"signal_abort.dump"),
+
+    {ok, Node} = start_node(Config),
+
+    _P1 = spawn(Node, ?MODULE, load, []),
+    _P2 = spawn(Node, ?MODULE, load, []),
+    _P3 = spawn(Node, ?MODULE, load, []),
+    _P4 = spawn(Node, ?MODULE, load, []),
+    _P5 = spawn(Node, ?MODULE, load, []),
+    _P6 = spawn(Node, ?MODULE, load, []),
+
+    timer:sleep(500),
+
+    true = rpc:call(Node, os, putenv, ["ERL_CRASH_DUMP",Dump]),
+    rpc:call(Node, erlang, halt, ["dump"]),
+
+    {ok, Bin} = get_dump_when_done(Dump),
+
+    ct:log("~s",[Bin]),
+
+    {match, Matches} = re:run(Bin,"Current Process: <",[global]),
+
+    ct:log("Found ~p",[Matches]),
+
+    true = length(Matches) > 1,
+
+    file:delete(Dump),
+
+    ok.
+
+get_dump_when_done(Dump) ->
+    case file:read_file_info(Dump) of
+        {ok, #file_info{ size = Sz }} ->
+            get_dump_when_done(Dump, Sz);
+        {error, enoent} ->
+            timer:sleep(100),
+            get_dump_when_done(Dump)
+    end.
+
+get_dump_when_done(Dump, Sz) ->
+    timer:sleep(100),
+    case file:read_file_info(Dump) of
+        {ok, #file_info{ size = Sz }} ->
+            file:read_file(Dump);
+        {ok, #file_info{ size = NewSz }} ->
+            get_dump_when_done(Dump, NewSz)
+    end.
+
+load() ->
+    lists:seq(1,10000),
+    load().
+
+start_node(Config) when is_list(Config) ->
+    Pa = filename:dirname(code:which(?MODULE)),
+    Name = list_to_atom(atom_to_list(?MODULE)
+                        ++ "-"
+                        ++ atom_to_list(proplists:get_value(testcase, Config))
+                        ++ "-"
+                        ++ integer_to_list(erlang:system_time(second))
+                        ++ "-"
+                        ++ integer_to_list(erlang:unique_integer([positive]))),
+    test_server:start_node(Name, slave, [{args, "-pa "++Pa}]).
diff --git a/erts/emulator/test/efile_SUITE.erl b/erts/emulator/test/efile_SUITE.erl
index f0e1bcf04b..16d581a567 100644
--- a/erts/emulator/test/efile_SUITE.erl
+++ b/erts/emulator/test/efile_SUITE.erl
@@ -19,93 +19,17 @@
 
 -module(efile_SUITE).
 -export([all/0, suite/0]).
--export([iter_max_files/1, async_dist/1]).
+-export([iter_max_files/1, proc_zero_sized_files/1]).
 
--export([do_iter_max_files/2, do_async_dist/1]).
+-export([do_iter_max_files/2]).
 
 -include_lib("common_test/include/ct.hrl").
+-include_lib("stdlib/include/assert.hrl").
 
 suite() -> [{ct_hooks,[ts_install_cth]}].
 
 all() -> 
-    [iter_max_files, async_dist].
-
-do_async_dist(Dir) ->
-    X = 100,
-    AT = erlang:system_info(thread_pool_size),
-    Keys = file_keys(Dir,AT*X,[],[]),
-    Tab = ets:new(x,[ordered_set]),
-    [ ets:insert(Tab,{N,0}) || N <- lists:seq(0,AT-1) ],
-    [ ets:update_counter(Tab,(N rem AT),1) || N <- Keys ],
-    Res = [ V || {_,V} <- ets:tab2list(Tab) ],
-    ets:delete(Tab),
-    {Res, sdev(Res)/X}.
-
-sdev(List) ->
-    Len = length(List),
-    Mean = lists:sum(List)/Len,
-    math:sqrt(lists:sum([ (X - Mean) * (X - Mean) || X <- List ]) / Len).
-
-file_keys(_,0,FdList,FnList) ->
-    [ file:close(FD) || FD <- FdList ],
-    [ file:delete(FN) || FN <- FnList ],
-    [];
-file_keys(Dir,Num,FdList,FnList) ->
-    Name = "dummy"++integer_to_list(Num),
-    FN = filename:join([Dir,Name]),
-    case file:open(FN,[write,raw]) of
-        {ok,FD} ->
-            {file_descriptor,prim_file,{Port,_}} = FD,
-            <<X:32/integer-big>> = 
-            iolist_to_binary(erlang:port_control(Port,$K,[])),
-            [X | file_keys(Dir,Num-1,[FD|FdList],[FN|FnList])];
-        {error,_} ->
-            % Try freeing up FD's if there are any
-            case FdList of 
-                [] ->
-                    exit({cannot_open_file,FN});
-                _ ->
-                    [ file:close(FD) || FD <- FdList ],
-                    [ file:delete(F) || F <- FnList ],
-                    file_keys(Dir,Num,[],[])
-            end
-    end.
-
-%% Check that the distribution of files over async threads is fair
-async_dist(Config) when is_list(Config) ->
-    DataDir = proplists:get_value(data_dir,Config),
-    Dir = filename:dirname(code:which(?MODULE)),
-    AsyncSizes = [7,10,100,255,256,64,63,65],
-    Max = 0.5,
-
-    lists:foreach(fun(Size) ->
-                          {ok,Node} = 
-                          test_server:start_node
-                          (test_iter_max_files,slave,
-                           [{args,
-                             "+A "++integer_to_list(Size)++
-                             " -pa " ++ Dir}]),
-                          {Distr,SD} = rpc:call(Node,?MODULE,do_async_dist,
-                                                [DataDir]),
-                          test_server:stop_node(Node),
-                          if
-                              SD > Max ->
-                                  io:format("Bad async queue distribution for "
-                                            "~p async threads:~n"
-                                            "    Standard deviation is ~p~n"
-                                            "    Key distribution:~n    ~lp~n",
-                                            [Size,SD,Distr]),
-                                  exit({bad_async_dist,Size,SD,Distr});
-                              true ->
-                                  io:format("OK async queue distribution for "
-                                            "~p async threads:~n"
-                                            "    Standard deviation is ~p~n"
-                                            "    Key distribution:~n    ~lp~n",
-                                            [Size,SD,Distr]),
-                                  ok
-                          end
-                  end, AsyncSizes),
-    ok.
+    [iter_max_files, proc_zero_sized_files].
 
 %%
 %% Open as many files as possible. Do this several times and check 
@@ -113,6 +37,12 @@ async_dist(Config) when is_list(Config) ->
 %%
 
 iter_max_files(Config) when is_list(Config) ->
+    case os:type() of
+        {win32, _} -> {skip, "Windows lacks a hard limit on file handles"};
+        _ -> iter_max_files_1(Config)
+    end.
+
+iter_max_files_1(Config) ->
     DataDir = proplists:get_value(data_dir,Config),
     TestFile = filename:join(DataDir, "existing_file"),
     N = 10,
@@ -162,3 +92,44 @@ open_files(Name) ->
             %		  io:format("Error reason: ~p", [_Reason]),
             []
     end.
+
+%% @doc If /proc filesystem exists (no way to know if it is real proc or just
+%% a /proc directory), let's read some zero sized files 500 times each, while
+%% ensuring that response isn't empty << >>
+proc_zero_sized_files(Config) when is_list(Config) ->
+    {Type, Flavor} = os:type(),
+    %% Some files which exist on Linux but might be missing on other systems
+    Inputs = ["/proc/cpuinfo",
+              "/proc/meminfo",
+              "/proc/partitions",
+              "/proc/swaps",
+              "/proc/version",
+              "/proc/uptime",
+              %% curproc is present on freebsd
+              "/proc/curproc/cmdline"],
+    case filelib:is_dir("/proc") of
+        false -> {skip, "/proc not found"}; % skip the test if no /proc
+        _ when Type =:= unix andalso Flavor =:= sunos ->
+            %% SunOS has a /proc, but no zero sized special files
+            {skip, "sunos does not have any zero sized special files"};
+        true ->
+            %% Take away files which do not exist in proc
+            Inputs1 = lists:filter(fun filelib:is_file/1, Inputs),
+
+            %% Fail if none of mentioned files exist in /proc, did we just get
+            %% a normal /proc directory without any special files?
+            ?assertNotEqual([], Inputs1),
+
+            %% For 6 inputs and 500 attempts each this do run anywhere
+            %% between 500 and 3000 function calls.
+            lists:foreach(
+                fun(Filename) -> do_proc_zero_sized(Filename, 500) end,
+                Inputs1)
+    end.
+
+%% @doc Test one file N times to also trigger possible leaking fds and memory
+do_proc_zero_sized(_Filename, 0) -> ok;
+do_proc_zero_sized(Filename, N) ->
+    Data = file:read_file(Filename),
+    ?assertNotEqual(<<>>, Data),
+    do_proc_zero_sized(Filename, N-1).
diff --git a/erts/emulator/test/emulator_smoke.spec b/erts/emulator/test/emulator_smoke.spec
index b2d0de8835..fc98ba6823 100644
--- a/erts/emulator/test/emulator_smoke.spec
+++ b/erts/emulator/test/emulator_smoke.spec
@@ -7,3 +7,4 @@
     [consistency],"Not reliable in October and March"}.
 {cases,'Dir',crypto_SUITE,[t_md5]}.
 {cases,'Dir',float_SUITE,[fpe,cmp_integer]}.
+{cases,'Dir',erts_debug_SUITE,[df]}.
diff --git a/erts/emulator/test/erl_link_SUITE.erl b/erts/emulator/test/erl_link_SUITE.erl
index 5622cce980..a66ca7a57d 100644
--- a/erts/emulator/test/erl_link_SUITE.erl
+++ b/erts/emulator/test/erl_link_SUITE.erl
@@ -200,13 +200,16 @@ monitor_nodes(Config) when is_list(Config) ->
     monitor_node(A, true),
     check_monitor_node(self(), A, 1),
     check_monitor_node(self(), B, 3),
+    ok = receive {nodedown, C} -> ok after 1000 -> timeout end,
+    %%OTP-21: monitor_node(_,false) does not trigger auto-connect anymore
+    %%        and therefore no nodedown if it fails.
+    %%ok = receive {nodedown, C} -> ok after 1000 -> timeout end,
+    ok = receive {nodedown, C} -> ok after 1000 -> timeout end,
+    ok = receive {nodedown, D} -> ok after 1000 -> timeout end,
+    ok = receive {nodedown, D} -> ok after 1000 -> timeout end,
     check_monitor_node(self(), C, 0),
     check_monitor_node(self(), D, 0),
-    receive {nodedown, C} -> ok end,
-    receive {nodedown, C} -> ok end,
-    receive {nodedown, C} -> ok end,
-    receive {nodedown, D} -> ok end,
-    receive {nodedown, D} -> ok end,
+
     stop_node(A),
     receive {nodedown, A} -> ok end,
     check_monitor_node(self(), A, 0),
@@ -533,7 +536,7 @@ freeze_node(Node, MS) ->
                fun () ->
                        erts_debug:set_internal_state(available_internal_state,
                                                      true),
-                       dport_send(Freezer, DoingIt),
+                       dctrl_dop_send(Freezer, DoingIt),
                        receive after Own -> ok end,
                        erts_debug:set_internal_state(block, MS+Own)
                end),
@@ -544,20 +547,22 @@ make_busy(Node, Time) when is_integer(Time) ->
     Own = 500,
     freeze_node(Node, Time+Own), 
     Data = busy_data(),
+    DCtrl = dctrl(Node),
     %% first make port busy
     Pid = spawn_link(fun () ->
                              forever(fun () ->
-                                             dport_reg_send(Node,
-                                                            '__noone__',
-                                                            Data)
+                                             dctrl_dop_reg_send(Node,
+                                                                '__noone__',
+                                                                Data)
                                      end)
                      end),
     receive after Own -> ok end,
     wait_until(fun () ->
-                       case process_info(Pid, status) of
-                           {status, suspended} -> true;
-                           _ -> false
-                       end
+                  case {DCtrl, process_info(Pid, status)} of
+                      {DPrt, {status, suspended}} when is_port(DPrt) -> true;
+                      {DPid, {status, waiting}} when is_pid(DPid) -> true;
+                      _ -> false
+                  end
                end),
     %% then dist entry
     make_busy(Node, [nosuspend], Data),
@@ -1048,42 +1053,45 @@ stop_node(Node) ->
 -define(DOP_DEMONITOR_P,	20).
 -define(DOP_MONITOR_P_EXIT,	21).
 
-dport_send(To, Msg) ->
-    Node = node(To),
-    DPrt = case dport(Node) of
-               undefined ->
-                   pong = net_adm:ping(Node),
-                   dport(Node);
-               Prt ->
-                   Prt
-           end,
-    port_command(DPrt, [dmsg_hdr(),
-                        dmsg_ext({?DOP_SEND,
-                                  ?COOKIE,
-                                  To}),
-                        dmsg_ext(Msg)]).
-
-dport_reg_send(Node, Name, Msg) ->
-    DPrt = case dport(Node) of
-               undefined ->
-                   pong = net_adm:ping(Node),
-                   dport(Node);
-               Prt ->
-                   Prt
-           end,
-    port_command(DPrt, [dmsg_hdr(),
-                        dmsg_ext({?DOP_REG_SEND,
-                                  self(),
-                                  ?COOKIE,
-                                  Name}),
-                        dmsg_ext(Msg)]).
-
-dport(Node) when is_atom(Node) ->
+ensure_dctrl(Node) ->
+    case dctrl(Node) of
+        undefined ->
+            pong = net_adm:ping(Node),
+            dctrl(Node);
+        DCtrl ->
+            DCtrl
+    end.
+
+dctrl_send(DPrt, Data) when is_port(DPrt) ->
+    port_command(DPrt, Data);
+dctrl_send(DPid, Data) when is_pid(DPid) ->
+    Ref = make_ref(),
+    DPid ! {send, self(), Ref, Data},
+    receive {Ref, Res} -> Res end.
+
+dctrl_dop_send(To, Msg) ->
+    dctrl_send(ensure_dctrl(node(To)),
+               [dmsg_hdr(),
+                dmsg_ext({?DOP_SEND,
+                          ?COOKIE,
+                          To}),
+                dmsg_ext(Msg)]).
+
+dctrl_dop_reg_send(Node, Name, Msg) ->
+    dctrl_send(ensure_dctrl(Node),
+               [dmsg_hdr(),
+                dmsg_ext({?DOP_REG_SEND,
+                          self(),
+                          ?COOKIE,
+                          Name}),
+                dmsg_ext(Msg)]).
+
+dctrl(Node) when is_atom(Node) ->
     case catch erts_debug:get_internal_state(available_internal_state) of
         true -> true;
         _ -> erts_debug:set_internal_state(available_internal_state, true)
     end,
-    erts_debug:get_internal_state({dist_port, Node}).
+    erts_debug:get_internal_state({dist_ctrl, Node}).
 
 dmsg_hdr() ->
     [131, % Version Magic
diff --git a/erts/emulator/test/estone_SUITE.erl b/erts/emulator/test/estone_SUITE.erl
index 8b336b366d..c9c1867049 100644
--- a/erts/emulator/test/estone_SUITE.erl
+++ b/erts/emulator/test/estone_SUITE.erl
@@ -20,7 +20,7 @@
 -module(estone_SUITE).
 %% Test functions
 -export([all/0, suite/0, groups/0,
-	 estone/1, estone_bench/1]).
+	 estone/1, estone_bench/1, pgo/0]).
 
 %% Internal exports for EStone tests
 -export([lists/1,
@@ -44,9 +44,9 @@
 	 links/1,lproc/1,
 	 run_micro/3,p1/1,ppp/3,macro/2,micros/0]).
 
-
--include_lib("common_test/include/ct.hrl").
+-ifndef(PGO).
 -include_lib("common_test/include/ct_event.hrl").
+-endif.
 
 %% EStone defines
 -define(TOTAL, (3000 * 1000 * 100)).   %% 300 secs
@@ -85,13 +85,28 @@ estone(Config) when is_list(Config) ->
 estone_bench(Config) ->
     DataDir = proplists:get_value(data_dir,Config),
     L = ?MODULE:macro(?MODULE:micros(),DataDir),
-    [ct_event:notify(
-       #event{name = benchmark_data, 
-	      data = [{name,proplists:get_value(title,Mark)},
-		      {value,proplists:get_value(estones,Mark)}]})
-     || Mark <- L],
+    {Total, Stones} = sum_micros(L, 0, 0),
+    notify([[{title,"ESTONES"}, {estones, Stones}] | L]),
     L.
 
+-ifndef(PGO).
+notify(Marks) ->
+    [ct_event:notify(
+       #event{name = benchmark_data,
+	      data = [{name,proplists:get_value(title, Mark)},
+		      {value,proplists:get_value(estones, Mark)}]})
+     || Mark <- Marks].
+-else.
+notify(_) ->
+    ok.
+-endif.
+
+%% The benchmarks to run in order to guide PGO (profile guided optimisation)
+pgo() ->
+    %% We run all benchmarks except the port_io as we don't want to
+    %% have to build a custom port.
+    Micros = ?MODULE:micros() -- [micro(port_io)],
+    ?MODULE:macro(Micros,[]).
 
 %%
 %% Calculate CPU speed
@@ -364,7 +379,7 @@ monotonic_time() ->
     try erlang:monotonic_time() catch error:undef -> erlang:now() end.
 
 subtr(Before, After) when is_integer(Before), is_integer(After) ->
-    erlang:convert_time_unit(After-Before, native, microsecond);
+    erlang:convert_time_unit(After-Before, native, 1000000);
 subtr({_,_,_}=Before, {_,_,_}=After) ->
     timer:now_diff(After, Before).
 
diff --git a/erts/emulator/test/exception_SUITE.erl b/erts/emulator/test/exception_SUITE.erl
index aaca522da6..da0292f385 100644
--- a/erts/emulator/test/exception_SUITE.erl
+++ b/erts/emulator/test/exception_SUITE.erl
@@ -21,7 +21,7 @@
 -module(exception_SUITE).
 
 -export([all/0, suite/0,
-         badmatch/1, pending_errors/1, nil_arith/1,
+         badmatch/1, pending_errors/1, nil_arith/1, top_of_stacktrace/1,
          stacktrace/1, nested_stacktrace/1, raise/1, gunilla/1, per/1,
          exception_with_heap_frag/1, line_numbers/1]).
 
@@ -31,13 +31,17 @@
 -include_lib("common_test/include/ct.hrl").
 -import(lists, [foreach/2]).
 
+%% The range analysis of the HiPE compiler results in a system limit error
+%% during compilation instead of at runtime, so do not perform this analysis.
+-compile([{hipe, [no_icode_range]}]).
+
 suite() ->
     [{ct_hooks,[ts_install_cth]},
      {timetrap, {minutes, 1}}].
 
 all() -> 
-    [badmatch, pending_errors, nil_arith, stacktrace,
-     nested_stacktrace, raise, gunilla, per,
+    [badmatch, pending_errors, nil_arith, top_of_stacktrace,
+     stacktrace, nested_stacktrace, raise, gunilla, per,
      exception_with_heap_frag, line_numbers].
 
 -define(try_match(E),
@@ -241,7 +245,54 @@ ba_bnot(A) ->
     io:format("bnot ~p", [A]),
     {'EXIT', {badarith, _}} = (catch bnot A).
 
+%% Test that BIFs are added to the top of the stacktrace.
+
+top_of_stacktrace(Conf) when is_list(Conf) ->
+    %% Arithmetic operators
+    {'EXIT', {badarith, [{erlang, '+', [1, ok], _} | _]}} = (catch my_add(1, ok)),
+    {'EXIT', {badarith, [{erlang, '-', [1, ok], _} | _]}} = (catch my_minus(1, ok)),
+    {'EXIT', {badarith, [{erlang, '*', [1, ok], _} | _]}} = (catch my_times(1, ok)),
+    {'EXIT', {badarith, [{erlang, 'div', [1, ok], _} | _]}} = (catch my_div(1, ok)),
+    {'EXIT', {badarith, [{erlang, 'div', [1, 0], _} | _]}} = (catch my_div(1, 0)),
+    {'EXIT', {badarith, [{erlang, 'rem', [1, ok], _} | _]}} = (catch my_rem(1, ok)),
+    {'EXIT', {badarith, [{erlang, 'rem', [1, 0], _} | _]}} = (catch my_rem(1, 0)),
+
+    %% Bit operators
+    {'EXIT', {badarith, [{erlang, 'band', [1, ok], _} | _]}} = (catch my_band(1, ok)),
+    {'EXIT', {badarith, [{erlang, 'bor', [1, ok], _} | _]}} = (catch my_bor(1, ok)),
+    {'EXIT', {badarith, [{erlang, 'bsl', [1, ok], _} | _]}} = (catch my_bsl(1, ok)),
+    {'EXIT', {badarith, [{erlang, 'bsr', [1, ok], _} | _]}} = (catch my_bsr(1, ok)),
+    {'EXIT', {badarith, [{erlang, 'bxor', [1, ok], _} | _]}} = (catch my_bxor(1, ok)),
+    {'EXIT', {badarith, [{erlang, 'bnot', [ok], _} | _]}} = (catch my_bnot(ok)),
+
+    %% Tuples
+    {'EXIT', {badarg, [{erlang, element, [1, ok], _} | _]}} = (catch my_element(1, ok)),
+    {'EXIT', {badarg, [{erlang, element, [ok, {}], _} | _]}} = (catch my_element(ok, {})),
+    {'EXIT', {badarg, [{erlang, element, [1, {}], _} | _]}} = (catch my_element(1, {})),
+    {'EXIT', {badarg, [{erlang, element, [1, {}], _} | _]}} = (catch element(1, erlang:make_tuple(0, ok))),
+
+    %% System limits
+    Maxbig = maxbig(),
+    MinusMaxbig = -Maxbig,
+    {'EXIT', {system_limit, [{erlang, '+', [Maxbig, 1], _} | _]}} = (catch my_add(Maxbig, 1)),
+    {'EXIT', {system_limit, [{erlang, '+', [Maxbig, 1], _} | _]}} = (catch my_add(maxbig_gc(), 1)),
+    {'EXIT', {system_limit, [{erlang, '-', [MinusMaxbig, 1], _} | _]}} = (catch my_minus(-Maxbig, 1)),
+    {'EXIT', {system_limit, [{erlang, '-', [MinusMaxbig, 1], _} | _]}} = (catch my_minus(-maxbig_gc(), 1)),
+    {'EXIT', {system_limit, [{erlang, '*', [Maxbig, 2], _} | _]}} = (catch my_times(Maxbig, 2)),
+    {'EXIT', {system_limit, [{erlang, '*', [Maxbig, 2], _} | _]}} = (catch my_times(maxbig_gc(), 2)),
+    {'EXIT', {system_limit, [{erlang, 'bnot', [Maxbig], _} | _]}} = (catch my_bnot(Maxbig)),
+    {'EXIT', {system_limit, [{erlang, 'bnot', [Maxbig], _} | _]}} = (catch my_bnot(maxbig_gc())),
+    ok.
+
+maxbig() ->
+    %% We assume that the maximum arity is (1 bsl 19) - 1.
+    Ws = erlang:system_info(wordsize),
+    (((1 bsl ((16777184 * (Ws div 4))-1)) - 1) bsl 1) + 1.
 
+maxbig_gc() ->
+    Maxbig = maxbig(),
+    erlang:garbage_collect(),
+    Maxbig.
 
 stacktrace(Conf) when is_list(Conf) ->
     Tag = make_ref(),
@@ -253,9 +304,9 @@ stacktrace(Conf) when is_list(Conf) ->
     St1 = erase(stacktrace1),
     St1 = erase(stacktrace2),
     St1 = erlang:get_stacktrace(),
-    {caught2,{error,badarith},[{?MODULE,my_add,2,_}|_]=St2} =
+    {caught2,{error,badarith},[{erlang,'+',[0,a],_},{?MODULE,my_add,2,_}|_]=St2} =
     stacktrace_1({'div',{1,0}}, error, {'add',{0,a}}),
-    [{?MODULE,my_div,2,_}|_] = erase(stacktrace1),
+    [{erlang,'div',[1,0],_},{?MODULE,my_div,2,_}|_] = erase(stacktrace1),
     St2 = erase(stacktrace2),
     St2 = erlang:get_stacktrace(),
     {caught2,{error,{try_clause,V}},[{?MODULE,stacktrace_1,3,_}|_]=St3} =
@@ -308,13 +359,13 @@ nested_stacktrace(Conf) when is_list(Conf) ->
     nested_stacktrace_1({{value,{V,x1}},void,{V,x1}},
                         {void,void,void}),
     {caught1,
-     [{?MODULE,my_add,2,_}|_],
+     [{erlang,'+',[V,x1],_},{?MODULE,my_add,2,_}|_],
      value2,
-     [{?MODULE,my_add,2,_}|_]} =
+     [{erlang,'+',[V,x1],_},{?MODULE,my_add,2,_}|_]} =
     nested_stacktrace_1({{'add',{V,x1}},error,badarith},
                         {{value,{V,x2}},void,{V,x2}}),
     {caught1,
-     [{?MODULE,my_add,2,_}|_],
+     [{erlang,'+',[V,x1],_},{?MODULE,my_add,2,_}|_],
      {caught2,[{erlang,abs,[V],_}|_]},
      [{erlang,abs,[V],_}|_]} =
     nested_stacktrace_1({{'add',{V,x1}},error,badarith},
@@ -344,18 +395,18 @@ raise(Conf) when is_list(Conf) ->
     try 
         try foo({'div',{1,0}}) 
         catch
-            error:badarith ->
+            error:badarith:A0 ->
                 put(raise, A0 = erlang:get_stacktrace()),
                 erlang:raise(error, badarith, A0)
         end
     catch
-        error:badarith ->
+        error:badarith:A1 ->
             A1 = erlang:get_stacktrace(),
             A1 = get(raise)
     end,
     A = erlang:get_stacktrace(),
     A = get(raise),
-    [{?MODULE,my_div,2,_}|_] = A,
+    [{erlang,'div',[1, 0], _},{?MODULE,my_div,2,_}|_] = A,
     %%
     N = 8, % Must be even
     N = erlang:system_flag(backtrace_depth, N),
@@ -404,11 +455,20 @@ foo({raise,{Class,Reason,Stacktrace}}) ->
     erlang:raise(Class, Reason, Stacktrace).
 %%foo(function_clause) -> % must not be defined!
 
-my_div(A, B) ->
-    A div B.
+my_add(A, B) -> A + B.
+my_minus(A, B) -> A - B.
+my_times(A, B) -> A * B.
+my_div(A, B) -> A div B.
+my_rem(A, B) -> A rem B.
+
+my_band(A, B) -> A band B.
+my_bor(A, B) -> A bor B.
+my_bsl(A, B) -> A bsl B.
+my_bsr(A, B) -> A bsr B.
+my_bxor(A, B) -> A bxor B.
+my_bnot(A) -> bnot A.
 
-my_add(A, B) ->
-    A + B.
+my_element(A, B) -> element(A, B).
 
 my_abs(X) -> abs(X).
 
@@ -606,6 +666,15 @@ line_numbers(Config) when is_list(Config) ->
               {?MODULE,line_numbers,1,_}|_]}} =
     (catch applied_bif_2()),
 
+    {'EXIT',{badarith,
+             [{?MODULE,increment1,1,[{file,"increment.erl"},{line,45}]},
+              {?MODULE,line_numbers,1,_}|_]}} =
+        (catch increment1(x)),
+    {'EXIT',{badarith,
+             [{?MODULE,increment2,1,[{file,"increment.erl"},{line,48}]},
+              {?MODULE,line_numbers,1,_}|_]}} =
+        (catch increment2(x)),
+
     ok.
 
 id(I) -> I.
@@ -706,3 +775,15 @@ applied_bif_2() ->				%Line 8
     R = process_info(self(), current_location),	%Line 9
     fail = R,					%Line 10
     ok.						%Line 11
+
+%% The increment instruction used to decrement the instruction
+%% pointer, which would cause the line number in a stack trace to
+%% be the previous line number.
+
+-file("increment.erl", 42).
+increment1(Arg) ->                              %Line 43
+    Res = id(Arg),                              %Line 44
+    Res + 1.                                    %Line 45
+increment2(Arg) ->                              %Line 46
+    _ = id(Arg),                                %Line 47
+    Arg + 1.                                    %Line 48
diff --git a/erts/emulator/test/guard_SUITE.erl b/erts/emulator/test/guard_SUITE.erl
index 1a93a9f5c2..f2c1595392 100644
--- a/erts/emulator/test/guard_SUITE.erl
+++ b/erts/emulator/test/guard_SUITE.erl
@@ -500,7 +500,7 @@ all_types() ->
      {atom, xxxx},
      {ref, make_ref()},
      {pid, self()},
-     {port, open_port({spawn, efile}, [])},
+     {port, make_port()},
      {function, fun(_) -> "" end},
      {function, fun erlang:abs/1},
      {binary, list_to_binary([])},
@@ -551,4 +551,7 @@ type_test(bitstring, X) when is_bitstring(X) ->
 type_test(function, X) when is_function(X) ->
     function.
 
+make_port() ->
+    hd(erlang:ports()).
+
 id(I) -> I.
diff --git a/erts/emulator/test/lttng_SUITE.erl b/erts/emulator/test/lttng_SUITE.erl
index a012fa1da2..19c3844c40 100644
--- a/erts/emulator/test/lttng_SUITE.erl
+++ b/erts/emulator/test/lttng_SUITE.erl
@@ -81,7 +81,6 @@ end_per_testcase(Case, _Config) ->
 
 %% Not tested yet
 %%   org_erlang_otp:driver_process_exit
-%%   org_erlang_otp:driver_event
 
 %% tracepoints
 %%
@@ -100,7 +99,6 @@ end_per_testcase(Case, _Config) ->
 %%   org_erlang_otp:driver_flush
 %%   org_erlang_otp:driver_stop_select
 %%   org_erlang_otp:driver_timeout
-%%   org_erlang_otp:driver_event
 %%   org_erlang_otp:driver_ready_output
 %%   org_erlang_otp:driver_ready_input
 %%   org_erlang_otp:driver_output
@@ -431,7 +429,6 @@ txt() ->
       "%%   org_erlang_otp:driver_flush\n"
       "%%   org_erlang_otp:driver_stop_select\n"
       "%%   org_erlang_otp:driver_timeout\n"
-      "%%   org_erlang_otp:driver_event\n"
       "%%   org_erlang_otp:driver_ready_output\n"
       "%%   org_erlang_otp:driver_ready_input\n"
       "%%   org_erlang_otp:driver_output\n"
diff --git a/erts/emulator/test/map_SUITE.erl b/erts/emulator/test/map_SUITE.erl
index 02f3c89318..c9e971af8a 100644
--- a/erts/emulator/test/map_SUITE.erl
+++ b/erts/emulator/test/map_SUITE.erl
@@ -52,7 +52,7 @@
          t_bif_map_values/1,
          t_bif_map_to_list/1,
          t_bif_map_from_list/1,
-         t_bif_erts_internal_maps_to_list/1,
+         t_bif_map_next/1,
 
          %% erlang
          t_erlang_hash/1,
@@ -119,7 +119,7 @@ all() -> [t_build_and_match_literals, t_build_and_match_literals_large,
           t_bif_map_update,
           t_bif_map_values,
           t_bif_map_to_list, t_bif_map_from_list,
-          t_bif_erts_internal_maps_to_list,
+          t_bif_map_next,
 
           %% erlang
           t_erlang_hash, t_map_encode_decode,
@@ -2364,41 +2364,71 @@ t_bif_map_from_list(Config) when is_list(Config) ->
     {'EXIT', {badarg,_}} = (catch maps:from_list(id(42))),
     ok.
 
-t_bif_erts_internal_maps_to_list(Config) when is_list(Config) ->
-    %% small maps
-    [] = erts_internal:maps_to_list(#{},-1),
-    [] = erts_internal:maps_to_list(#{},-2),
-    [] = erts_internal:maps_to_list(#{},10),
-    [{a,1},{b,2}] = lists:sort(erts_internal:maps_to_list(#{a=>1,b=>2}, 2)),
-    [{a,1},{b,2}] = lists:sort(erts_internal:maps_to_list(#{a=>1,b=>2}, -1)),
-    [{_,_}] = erts_internal:maps_to_list(#{a=>1,b=>2}, 1),
-    [{a,1},{b,2},{c,3}] = lists:sort(erts_internal:maps_to_list(#{c=>3,a=>1,b=>2},-2)),
-    [{a,1},{b,2},{c,3}] = lists:sort(erts_internal:maps_to_list(#{c=>3,a=>1,b=>2},3)),
-    [{a,1},{b,2},{c,3}] = lists:sort(erts_internal:maps_to_list(#{c=>3,a=>1,b=>2},5)),
-    [{_,_},{_,_}] = erts_internal:maps_to_list(#{c=>3,a=>1,b=>2},2),
-    [{_,_}] = erts_internal:maps_to_list(#{c=>3,a=>1,b=>2},1),
-    [] = erts_internal:maps_to_list(#{c=>3,a=>1,b=>2},0),
-
-    %% big maps
-    M = maps:from_list([{I,ok}||I <- lists:seq(1,500)]),
-    [] = erts_internal:maps_to_list(M,0),
-    [{_,_}] = erts_internal:maps_to_list(M,1),
-    [{_,_},{_,_}] = erts_internal:maps_to_list(M,2),
-    Ls1 = erts_internal:maps_to_list(M,10),
-    10 = length(Ls1),
-    Ls2 = erts_internal:maps_to_list(M,20),
-    20 = length(Ls2),
-    Ls3 = erts_internal:maps_to_list(M,120),
-    120 = length(Ls3),
-    Ls4 = erts_internal:maps_to_list(M,-1),
-    500 = length(Ls4),
+t_bif_map_next(Config) when is_list(Config) ->
 
-    %% error cases
-    {'EXIT', {{badmap,[{a,b},b]},_}} = (catch erts_internal:maps_to_list(id([{a,b},b]),id(1))),
-    {'EXIT', {badarg,_}} = (catch erts_internal:maps_to_list(id(#{}),id(a))),
-    {'EXIT', {badarg,_}} = (catch erts_internal:maps_to_list(id(#{1=>2}),id(<<>>))),
+    erts_debug:set_internal_state(available_internal_state, true),
+
+    try
+
+        none = maps:next(maps:iterator(id(#{}))),
+
+        verify_iterator(#{}),
+        verify_iterator(#{a => 1, b => 2, c => 3}),
+
+        %% Use fatmap in order to test iterating in very deep maps
+        FM = fatmap(43),
+        verify_iterator(FM),
+
+        {'EXIT', {{badmap,[{a,b},b]},_}} = (catch maps:iterator(id([{a,b},b]))),
+        {'EXIT', {badarg,_}} = (catch maps:next(id(a))),
+        {'EXIT', {badarg,_}} = (catch maps:next(id([a|FM]))),
+        {'EXIT', {badarg,_}} = (catch maps:next(id([1|#{}]))),
+        {'EXIT', {badarg,_}} = (catch maps:next(id([-1|#{}]))),
+        {'EXIT', {badarg,_}} = (catch maps:next(id([-1|FM]))),
+        {'EXIT', {badarg,_}} = (catch maps:next(id([16#FFFFFFFFFFFFFFFF|FM]))),
+        {'EXIT', {badarg,_}} = (catch maps:next(id([-16#FFFFFFFFFFFFFFFF|FM]))),
+
+        %% This us a whitebox test that the error code works correctly.
+        %% It uses a path for a tree of depth 4 and tries to do next on
+        %% each of those paths.
+        (fun F(0) -> ok;
+             F(N) ->
+                 try maps:next([N|FM]) of
+                     none ->
+                         F(N-1);
+                     {_K,_V,_I} ->
+                         F(N-1)
+                 catch error:badarg ->
+                         F(N-1)
+                 end
+         end)(16#FFFF),
+
+        ok
+    after
+            erts_debug:set_internal_state(available_internal_state, false)
+    end.
+
+verify_iterator(Map) ->
+    KVs = t_fold(fun(K, V, A) -> [{K, V} | A] end, [], Map),
+
+    %% Verify that KVs created by iterating Map is of
+    %% correct size and contains all elements
+    true = length(KVs) == maps:size(Map),
+    [maps:get(K, Map) || {K, _} <- KVs],
     ok.
 
+
+t_fold(Fun, Init, Map) ->
+    t_fold_1(Fun, Init, maps:iterator(Map)).
+
+t_fold_1(Fun, Acc, Iter) ->
+    case maps:next(Iter) of
+        {K, V, NextIter} ->
+            t_fold_1(Fun, Fun(K,V,Acc), NextIter);
+        none ->
+            Acc
+    end.
+
 t_bif_build_and_check(Config) when is_list(Config) ->
     ok = check_build_and_remove(750,[fun(K) -> [K,K] end,
 				     fun(K) -> [float(K),K] end,
diff --git a/erts/emulator/test/map_SUITE_data/badmap_17.beam b/erts/emulator/test/map_SUITE_data/badmap_17.beam
index 277fc34b94..6f79bb8c2c 100644
--- a/erts/emulator/test/map_SUITE_data/badmap_17.beam
+++ b/erts/emulator/test/map_SUITE_data/badmap_17.beam
diff --git a/erts/emulator/test/map_SUITE_data/badmap_17.erl b/erts/emulator/test/map_SUITE_data/badmap_17.erl
index 0ec65e0e33..887fc2e5e3 100644
--- a/erts/emulator/test/map_SUITE_data/badmap_17.erl
+++ b/erts/emulator/test/map_SUITE_data/badmap_17.erl
@@ -1,7 +1,7 @@
 -module(badmap_17).
 -export([update/1]).
 
-%% Compile this source file with OTP 17.
+%% Compile this source file with OTP 17.0.
 
 update(Map) ->
     try
@@ -17,10 +17,42 @@ update(Map) ->
     catch
 	error:{badmap,Map} ->
 	    ok
-    end.
+    end,
+    try
+	update_3(Map),
+	error(update_did_not_fail)
+    catch
+	error:{badmap,Map} ->
+	    ok
+    end,
+    ok = update_4(Map),
+    ok = update_5(Map),
+    ok.
 
 update_1(M) ->
     M#{a=>42}.
 
 update_2(M) ->
     M#{a:=42}.
+
+update_3(M) ->
+    id(M),
+    M#{a=>42}.
+
+update_4(M) when M#{a=>b} =:= M ->
+    did_not_fail;
+update_4(_) ->
+    ok.
+
+update_5(M) ->
+    id(M),
+    case id(true) of
+        true when M#{a=>b} =:= M ->
+            did_not_fail;
+        true ->
+            ok
+    end.
+
+id(I) ->
+    I.
+
diff --git a/erts/emulator/test/nif_SUITE.erl b/erts/emulator/test/nif_SUITE.erl
index 4811244b98..85c302e310 100644
--- a/erts/emulator/test/nif_SUITE.erl
+++ b/erts/emulator/test/nif_SUITE.erl
@@ -25,13 +25,14 @@
 %%-define(CHECK(Exp,Got), Exp = Got).
 
 -include_lib("common_test/include/ct.hrl").
+-include_lib("stdlib/include/assert.hrl").
 
 -export([all/0, suite/0, groups/0,
          init_per_group/2, end_per_group/2,
 	 init_per_testcase/2, end_per_testcase/2,
          basic/1, reload_error/1, upgrade/1, heap_frag/1,
          t_on_load/1,
-         select/1,
+         select/1, select_steal/1,
          monitor_process_a/1,
          monitor_process_b/1,
          monitor_process_c/1,
@@ -42,9 +43,9 @@
 	 types/1, many_args/1, binaries/1, get_string/1, get_atom/1,
 	 maps/1,
 	 api_macros/1,
-	 from_array/1, iolist_as_binary/1, resource/1, resource_binary/1, 
+	 from_array/1, iolist_as_binary/1, resource/1, resource_binary/1,
 	 resource_takeover/1,
-	 threading/1, send/1, send2/1, send3/1, send_threaded/1, neg/1, 
+	 threading/1, send/1, send2/1, send3/1, send_threaded/1, neg/1,
 	 is_checks/1,
 	 get_length/1, make_atom/1, make_string/1, reverse_list_test/1,
 	 otp_9828/1,
@@ -79,7 +80,7 @@ all() ->
     [{group, G} || G <- api_groups()]
         ++
     [reload_error, heap_frag, types, many_args,
-     select,
+     select, select_steal,
      {group, monitor},
      monitor_frenzy,
      hipe,
@@ -144,7 +145,8 @@ init_per_testcase(nif_whereis_threaded, Config) ->
         true -> Config;
         false -> {skip, "No thread support"}
     end;
-init_per_testcase(select, Config) ->
+init_per_testcase(Select, Config) when Select =:= select;
+                                       Select =:= select_steal ->
     case os:type() of
         {win32,_} ->
             {skip, "Test not yet implemented for windows"};
@@ -152,6 +154,9 @@ init_per_testcase(select, Config) ->
             Config
     end;
 init_per_testcase(_Case, Config) ->
+    %% Clear any resource dtor data before test starts in case another tc
+    %% left it in a bad state
+    catch last_resource_dtor_call(),
     Config.
 
 end_per_testcase(t_on_load, _Config) ->
@@ -590,7 +595,71 @@ select_3(_Config) ->
     {_,_,2} = last_resource_dtor_call(),
     ok.
 
-check_stop_ret(?ERL_NIF_SELECT_STOP_CALLED) -> ok;    
+%% @doc The stealing child process for the select_steal test. Duplicates given
+%% W/RFds and runs select on them to steal
+select_steal_child_process(Parent, RFd) ->
+    %% Duplicate the resource with the same FD
+    {R2Fd, _R2Ptr} = dupe_resource_nif(RFd),
+    Ref2 = make_ref(),
+
+    %% Try to select from the child pid (steal from parent)
+    ?assertEqual(0, select_nif(R2Fd, ?ERL_NIF_SELECT_READ, R2Fd, null, Ref2)),
+    ?assertEqual([], flush(0)),
+    ?assertEqual(eagain, read_nif(R2Fd, 1)),
+
+    %% Check that now events arrive to this temporary process
+    Parent ! {self(), stage1}, % signal parent to send the <<"stolen1">>
+
+    %% Receive <<"stolen1">> via enif_select
+    ?assertEqual(0, select_nif(R2Fd, ?ERL_NIF_SELECT_READ, R2Fd, null, Ref2)),
+    ?assertMatch([{select, R2Fd, Ref2, ready_input}], flush()),
+    ?assertEqual(<<"stolen1">>, read_nif(R2Fd, 7)),
+
+    clear_select_nif(R2Fd),
+
+    % do not do this here - stop_selecting(R2Fd, R2Rsrc, Ref2),
+    Parent ! {self(), done}.
+
+%% @doc Similar to select/1 test, make a double ended pipe. Then try to steal
+%% the socket, see what happens.
+select_steal(Config) when is_list(Config) ->
+    ensure_lib_loaded(Config),
+
+    Ref = make_ref(),
+    {{RFd, RPtr}, {WFd, WPtr}} = pipe_nif(),
+
+    %% Bind the socket to current pid in enif_select
+    ?assertEqual(0, select_nif(RFd, ?ERL_NIF_SELECT_READ, RFd, null, Ref)),
+    ?assertEqual([], flush(0)),
+
+    %% Spawn a process and do some stealing
+    Parent = self(),
+    Pid = spawn_link(fun() -> select_steal_child_process(Parent, RFd) end),
+
+    %% Signal from the child to send the first message
+    {Pid, stage1} = receive_any(),
+    ?assertEqual(ok, write_nif(WFd, <<"stolen1">>)),
+
+    ?assertMatch([{Pid, done}], flush(1)),  % synchronize with the child
+
+    %% Try to select from the parent pid (steal back)
+    ?assertEqual(0, select_nif(RFd, ?ERL_NIF_SELECT_READ, RFd, Pid, Ref)),
+
+    %% Ensure that no data is hanging and close.
+    %% Rfd is stolen at this point.
+    check_stop_ret(select_nif(WFd, ?ERL_NIF_SELECT_STOP, WFd, null, Ref)),
+    ?assertMatch([{fd_resource_stop, WPtr, _}], flush()),
+    {1, {WPtr, 1}} = last_fd_stop_call(),
+
+    check_stop_ret(select_nif(RFd, ?ERL_NIF_SELECT_STOP, RFd, null, Ref)),
+    ?assertMatch([{fd_resource_stop, RPtr, _}], flush()),
+    {1, {RPtr, 1}} = last_fd_stop_call(),
+
+    ?assert(is_closed_nif(WFd)),
+
+    ok.
+
+check_stop_ret(?ERL_NIF_SELECT_STOP_CALLED) -> ok;
 check_stop_ret(?ERL_NIF_SELECT_STOP_SCHEDULED) -> ok.
 
 write_full(W, C) ->
@@ -1723,14 +1792,9 @@ send2(Config) when is_list(Config) ->
 
 %% Send msg from user thread
 send_threaded(Config) when is_list(Config) ->
-    case erlang:system_info(smp_support) of
-	true ->
-	    send2_do1(fun(ME,To) -> send_blob_thread_dbg(ME,To,join) end),
-	    send2_do1(fun(ME,To) -> send_blob_thread_and_join(ME,To) end),
-	    ok;
-	false ->
-	    {skipped,"No threaded send on non-SMP"}
-    end.
+    send2_do1(fun(ME,To) -> send_blob_thread_dbg(ME,To,join) end),
+    send2_do1(fun(ME,To) -> send_blob_thread_and_join(ME,To) end),
+    ok.
 
 
 send2_do1(SendBlobF) ->
@@ -2193,9 +2257,8 @@ nif_schedule(Config) when is_list(Config) ->
     {B,A} = call_nif_schedule(A, B),
     ok = try call_nif_schedule(1, 2)
 	 catch
-	     error:badarg ->
-		 [{?MODULE,call_nif_schedule,[1,2],_}|_] =
-		     erlang:get_stacktrace(),
+	     error:badarg:Stk ->
+		 [{?MODULE,call_nif_schedule,[1,2],_}|_] = Stk,
 		 ok
 	 end,
     ok.
@@ -2365,8 +2428,8 @@ nif_raise_exceptions(NifFunc) ->
                             erlang:apply(?MODULE,NifFunc,[Term]),
                             ct:fail({expected,Term})
                         catch
-                            error:Term ->
-                                [{?MODULE,NifFunc,[Term],_}|_] = erlang:get_stacktrace(),
+                            error:Term:Stk ->
+                                [{?MODULE,NifFunc,[Term],_}|_] = Stk,
                                 ok
                         end
                 end, ok, ExcTerms).
@@ -2973,14 +3036,17 @@ nif_ioq(Config) ->
          {enqbraw,a},
          {enqbraw,a, 5},
          {peek,   a},
+         {peek_head,  a},
          {deq,    a, 42},
 
          %% Test enqv
          {enqv,   a, 2, 100},
+         {peek_head,  a},
          {deq,    a, all},
 
          %% This skips all elements but one in the iolist
          {enqv,   a, 5, iolist_size(nif_ioq_payload(5)) - 1},
+         {peek_head,  a},
          {peek,   a},
 
          %% Test to enqueue a bunch of refc binaries
@@ -3010,9 +3076,13 @@ nif_ioq(Config) ->
 
     Q = ioq_nif(create),
 
+    false = ioq_nif(peek_head, Q),
+
     {'EXIT', {badarg, _}} = (catch ioq_nif(deq, Q, 1)),
     {'EXIT', {badarg, _}} = (catch ioq_nif(enqv, Q, 1, 1234)),
 
+    false = ioq_nif(peek_head, Q),
+
     {'EXIT', {badarg, _}} = (catch ioq_nif(enqv, Q, [atom_in_list], 0)),
     {'EXIT', {badarg, _}} = (catch ioq_nif(enqv, Q, [make_ref()], 0)),
     {'EXIT', {badarg, _}} = (catch ioq_nif(enqv, Q, [256], 0)),
@@ -3021,6 +3091,8 @@ nif_ioq(Config) ->
     {'EXIT', {badarg, _}} = (catch ioq_nif(enqv, Q, [1 bsl 64], 0)),
     {'EXIT', {badarg, _}} = (catch ioq_nif(enqv, Q, [{tuple}], 0)),
 
+    false = ioq_nif(peek_head, Q),
+
     {'EXIT', {badarg, _}} = (catch ioq_nif(inspect,  [atom_in_list], use_stack)),
     {'EXIT', {badarg, _}} = (catch ioq_nif(inspect,  [make_ref()], no_stack)),
     {'EXIT', {badarg, _}} = (catch ioq_nif(inspect,  [256], use_stack)),
@@ -3081,6 +3153,20 @@ nif_ioq_run([{peek, Name} = H|T], State) ->
 
     true = iolist_to_binary(B) == iolist_to_binary(Data),
     nif_ioq_run(T, State);
+nif_ioq_run([{peek_head, Name} = H|T], State) ->
+    #{ q := IOQ, b := B } = maps:get(Name, State),
+    RefData = iolist_to_binary(B),
+
+    ct:log("~p", [H]),
+
+    {true, QueueHead} = ioq_nif(peek_head, IOQ),
+    true = byte_size(QueueHead) > 0,
+
+    {RefHead, _Tail} = split_binary(RefData, byte_size(QueueHead)),
+
+    true = QueueHead =:= RefHead,
+
+    nif_ioq_run(T, State);
 nif_ioq_run([{deq, Name, all}|T], State) ->
     #{ q := IOQ, b := B } = maps:get(Name, State),
     Size = ioq_nif(size, IOQ),
@@ -3198,10 +3284,12 @@ binary_to_term_nif(_, _, _) -> ?nif_stub.
 port_command_nif(_, _) -> ?nif_stub.
 format_term_nif(_,_) -> ?nif_stub.
 select_nif(_,_,_,_,_) -> ?nif_stub.
+dupe_resource_nif(_) -> ?nif_stub.
 pipe_nif() -> ?nif_stub.
 write_nif(_,_) -> ?nif_stub.
 read_nif(_,_) -> ?nif_stub.
 is_closed_nif(_) -> ?nif_stub.
+clear_select_nif(_) -> ?nif_stub.
 last_fd_stop_call() -> ?nif_stub.
 alloc_monitor_resource_nif() -> ?nif_stub.
 monitor_process_nif(_,_,_,_) -> ?nif_stub.
diff --git a/erts/emulator/test/nif_SUITE_data/nif_SUITE.c b/erts/emulator/test/nif_SUITE_data/nif_SUITE.c
index b47d013bd2..fa9ae1015c 100644
--- a/erts/emulator/test/nif_SUITE_data/nif_SUITE.c
+++ b/erts/emulator/test/nif_SUITE_data/nif_SUITE.c
@@ -2448,6 +2448,13 @@ static int get_fd(ErlNifEnv* env, ERL_NIF_TERM term, struct fd_resource** rsrc)
     return 1;
 }
 
+/* Returns: badarg
+ *    Or an enif_select result, which is a combination of bits:
+ *    ERL_NIF_SELECT_STOP_CALLED = 1
+ *    ERL_NIF_SELECT_STOP_SCHEDULED = 2
+ *    ERL_NIF_SELECT_INVALID_EVENT = 4
+ *    ERL_NIF_SELECT_FAILED = 8
+ */
 static ERL_NIF_TERM select_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
 {
     struct fd_resource* fdr;
@@ -2479,6 +2486,9 @@ static ERL_NIF_TERM select_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv
 }
 
 #ifndef __WIN32__
+/*
+ * Create a read-write pipe with two fds (to read and to write)
+ */
 static ERL_NIF_TERM pipe_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
 {
     struct fd_resource* read_rsrc;
@@ -2514,6 +2524,30 @@ static ERL_NIF_TERM pipe_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]
                enif_make_tuple2(env, write_fd, make_pointer(env, write_rsrc)));
 }
 
+/*
+ * Create (dupe) of a resource with the same fd, to test stealing
+ */
+static ERL_NIF_TERM dupe_resource_nif(ErlNifEnv* env, int argc,
+                                      const ERL_NIF_TERM argv[]) {
+    struct fd_resource* orig_rsrc;
+
+    if (!get_fd(env, argv[0], &orig_rsrc)) {
+        return enif_make_badarg(env);
+    } else {
+        struct fd_resource* new_rsrc;
+        ERL_NIF_TERM new_fd;
+
+        new_rsrc = enif_alloc_resource(fd_resource_type,
+                                       sizeof(struct fd_resource));
+        new_rsrc->fd = orig_rsrc->fd;
+        new_rsrc->was_selected = 0;
+        new_fd = enif_make_resource(env, new_rsrc);
+        enif_release_resource(new_rsrc);
+
+        return enif_make_tuple2(env, new_fd, make_pointer(env, new_rsrc));
+    }
+}
+
 static ERL_NIF_TERM write_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
 {
     struct fd_resource* fdr;
@@ -2589,6 +2623,20 @@ static ERL_NIF_TERM is_closed_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM a
 
     return fdr->fd < 0 ? atom_true : atom_false;
 }
+
+static ERL_NIF_TERM clear_select_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+{
+    struct fd_resource* fdr = NULL;
+
+    if (!get_fd(env, argv[0], &fdr))
+        return enif_make_badarg(env);
+
+    fdr->fd = -1;
+    fdr->was_selected = 0;
+
+    return atom_ok;
+}
+
 #endif /* !__WIN32__ */
 
 
@@ -3355,6 +3403,15 @@ static ERL_NIF_TERM ioq(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
 		return enif_make_badarg(env);
 	    else
 		return enif_make_atom(env, "true");
+        } else if (enif_is_identical(argv[0], enif_make_atom(env, "peek_head"))) {
+            ERL_NIF_TERM head_term;
+
+            if(enif_ioq_peek_head(env, ioq->q, NULL, &head_term)) {
+                return enif_make_tuple2(env,
+                    enif_make_atom(env, "true"), head_term);
+            }
+
+            return enif_make_atom(env, "false");
         } else if (enif_is_identical(argv[0], enif_make_atom(env, "peek"))) {
             int iovlen, num, i, off = 0;
             SysIOVec *iov = enif_ioq_peek(ioq->q, &iovlen);
@@ -3476,8 +3533,10 @@ static ErlNifFunc nif_funcs[] =
 #ifndef __WIN32__
     {"pipe_nif", 0, pipe_nif},
     {"write_nif", 2, write_nif},
+    {"dupe_resource_nif", 1, dupe_resource_nif},
     {"read_nif", 2, read_nif},
     {"is_closed_nif", 1, is_closed_nif},
+    {"clear_select_nif", 1, clear_select_nif},
 #endif
     {"last_fd_stop_call", 0, last_fd_stop_call},
     {"alloc_monitor_resource_nif", 0, alloc_monitor_resource_nif},
diff --git a/erts/emulator/test/node_container_SUITE.erl b/erts/emulator/test/node_container_SUITE.erl
index 8e9e3cb05a..7df001fec5 100644
--- a/erts/emulator/test/node_container_SUITE.erl
+++ b/erts/emulator/test/node_container_SUITE.erl
@@ -405,6 +405,7 @@ node_table_gc(Config) when is_list(Config) ->
     PreKnown = nodes(known),
     io:format("PreKnown = ~p~n", [PreKnown]),
     make_node_garbage(0, 200000, 1000, []),
+    receive after 1000 -> ok end, %% Wait for thread progress...
     PostKnown = nodes(known),
     PostAreas = erlang:system_info(allocated_areas),
     io:format("PostKnown = ~p~n", [PostKnown]),
@@ -965,6 +966,8 @@ check_refc(ThisNodeName,ThisCreation,Table,EntryList) when is_list(EntryList) ->
                         {case Referrer of
                              {system,delayed_delete_timer} ->
                                  true;
+                             {system,thread_progress_delete_timer} ->
+                                 true;
                              _ ->
                                  DDT
                          end,
diff --git a/erts/emulator/test/num_bif_SUITE.erl b/erts/emulator/test/num_bif_SUITE.erl
index 1c76eb8019..17555d63c6 100644
--- a/erts/emulator/test/num_bif_SUITE.erl
+++ b/erts/emulator/test/num_bif_SUITE.erl
@@ -145,7 +145,7 @@ t_float_to_string(Config) when is_list(Config) ->
 				     123456789012345678.0, [{decimals, 237}])),
     {'EXIT', {badarg, _}} = (catch float_to_binary(
 				     123456789012345678.0, [{decimals, 237}])),
-    test_fts("1." ++ string:copies("0", 249) ++ "e+00",
+    test_fts("1." ++ lists:duplicate(249, $0) ++ "e+00",
 	     1.0,  [{scientific, 249}, compact]),
 
     X1 = float_to_list(1.0),
diff --git a/erts/emulator/test/port_SUITE.erl b/erts/emulator/test/port_SUITE.erl
index 730a17d7e8..e46665a881 100644
--- a/erts/emulator/test/port_SUITE.erl
+++ b/erts/emulator/test/port_SUITE.erl
@@ -1035,6 +1035,9 @@ huge_env(Config) when is_list(Config) ->
     try erlang:open_port({spawn,Cmd},[exit_status, {env, Env}]) of
         P ->
             receive
+                {P, {exit_status,N}} = M when N > 127->
+                    %% If exit status is > 127 something went very wrong
+                    ct:fail("Open port failed got ~p",[M]);
                 {P, {exit_status,N}} = M ->
                     %% We test that the exit status is an integer, this means
                     %% that the child program has started. If we get an atom
@@ -1662,13 +1665,7 @@ spawn_executable(Config) when is_list(Config) ->
     [ExactFile2,"hello world","dlrow olleh"] =
     run_echo_args_2(unicode:characters_to_binary("\""++ExactFile2++"\" "++"\"hello world\" \"dlrow olleh\"")),
 
-    ExeExt =
-    case string:to_lower(lists:last(string:tokens(ExactFile2,"."))) of
-        "exe" ->
-            ".exe";
-        _ ->
-            ""
-    end,
+    ExeExt = filename:extension(ExactFile2),
     Executable2 = "spoky name"++ExeExt,
     file:copy(ExactFile1,filename:join([SpaceDir,Executable2])),
     ExactFile3 = filename:nativename(filename:join([SpaceDir,Executable2])),
@@ -1836,7 +1833,7 @@ collect_data(Port) ->
     end.
 
 parse_echo_args_output(Data) ->
-    [lists:last(string:tokens(S,"|")) || S <- string:tokens(Data,"\r\n")].
+    [lists:last(string:lexemes(S,"|")) || S <- string:lexemes(Data,["\r\n",$\n])].
 
 %% Test that the emulator does not mix up ports when the port table wraps
 mix_up_ports(Config) when is_list(Config) ->
@@ -1962,7 +1959,7 @@ max_ports() ->
     erlang:system_info(port_limit).
 
 port_ix(Port) when is_port(Port) ->
-    ["#Port",_,PortIxStr] = string:tokens(erlang:port_to_list(Port),
+    ["#Port",_,PortIxStr] = string:lexemes(erlang:port_to_list(Port),
                                           "<.>"),
     list_to_integer(PortIxStr).
 
diff --git a/erts/emulator/test/port_trace_SUITE.erl b/erts/emulator/test/port_trace_SUITE.erl
index c78dc754a9..a1986397a8 100644
--- a/erts/emulator/test/port_trace_SUITE.erl
+++ b/erts/emulator/test/port_trace_SUITE.erl
@@ -78,13 +78,6 @@ end_per_group(_GroupName, Config) ->
     Config.
 
 
-init_per_testcase(driver_remote_send_term, Config) ->
-    case erlang:system_info(smp_support) of
-        false ->
-            {skip,"Only supported on smp systems"};
-        true ->
-            init_per_testcase(driver_remote_send_term_smp, Config)
-    end;
 init_per_testcase(Func, Config) when is_atom(Func), is_list(Config) ->
     erlang:trace(all, false, [all]),
     os:unsetenv("OUTPUTV"),
diff --git a/erts/emulator/test/receive_SUITE.erl b/erts/emulator/test/receive_SUITE.erl
index a12019ec83..1fe11428b4 100644
--- a/erts/emulator/test/receive_SUITE.erl
+++ b/erts/emulator/test/receive_SUITE.erl
@@ -25,14 +25,16 @@
 -include_lib("common_test/include/ct.hrl").
 
 -export([all/0, suite/0,
-	 call_with_huge_message_queue/1,receive_in_between/1]).
+	 call_with_huge_message_queue/1,receive_in_between/1,
+         receive_opt_exception/1,receive_opt_recursion/1]).
 
 suite() ->
     [{ct_hooks,[ts_install_cth]},
      {timetrap, {minutes, 3}}].
 
-all() -> 
-    [call_with_huge_message_queue, receive_in_between].
+all() ->
+    [call_with_huge_message_queue, receive_in_between,
+     receive_opt_exception, receive_opt_recursion].
 
 call_with_huge_message_queue(Config) when is_list(Config) ->
     Pid = spawn_link(fun echo_loop/0),
@@ -113,6 +115,60 @@ receive_one() ->
 	dummy -> ok
     end.
 
+receive_opt_exception(_Config) ->
+    Recurse = fun() ->
+                      %% Overwrite with the same mark,
+                      %% and never consume it.
+                      ThrowFun = fun() -> throw(aborted) end,
+                      aborted = (catch do_receive_opt_exception(ThrowFun)),
+                      ok
+              end,
+    do_receive_opt_exception(Recurse),
+
+    %% Eat the second message.
+    receive
+        Ref when is_reference(Ref) -> ok
+    end.
+
+do_receive_opt_exception(Disturber) ->
+    %% Create a receive mark.
+    Ref = make_ref(),
+    self() ! Ref,
+    Disturber(),
+    receive
+        Ref ->
+            ok
+    after 0 ->
+            error(the_expected_message_was_not_there)
+    end.
+
+receive_opt_recursion(_Config) ->
+    Recurse = fun() ->
+                      %% Overwrite with the same mark,
+                      %% and never consume it.
+                      NoOp = fun() -> ok end,
+                      BlackHole = spawn(NoOp),
+                      expected = do_receive_opt_recursion(BlackHole, NoOp, true),
+                      ok
+              end,
+    do_receive_opt_recursion(self(), Recurse, false),
+    ok.
+
+do_receive_opt_recursion(Recipient, Disturber, IsInner) ->
+    Ref = make_ref(),
+    Recipient ! Ref,
+    Disturber(),
+    receive
+        Ref -> ok
+    after 0 ->
+            case IsInner of
+                true ->
+                    expected;
+                false ->
+                    error(the_expected_message_was_not_there)
+            end
+    end.
+
 %%%
 %%% Common helpers.
 %%%
diff --git a/erts/emulator/test/scheduler_SUITE.erl b/erts/emulator/test/scheduler_SUITE.erl
index af33de237c..7eebbe8b19 100644
--- a/erts/emulator/test/scheduler_SUITE.erl
+++ b/erts/emulator/test/scheduler_SUITE.erl
@@ -57,6 +57,7 @@
 	 scheduler_suspend_basic/1,
 	 scheduler_suspend/1,
 	 dirty_scheduler_threads/1,
+         poll_threads/1,
 	 reader_groups/1]).
 
 suite() ->
@@ -72,6 +73,7 @@ all() ->
      {group, scheduler_bind}, scheduler_threads,
      scheduler_suspend_basic, scheduler_suspend,
      dirty_scheduler_threads,
+     poll_threads,
      reader_groups].
 
 groups() -> 
@@ -892,11 +894,9 @@ adjust_schedulers_online() ->
 
 read_affinity(Data) ->
     Exp = "pid " ++ os:getpid() ++ "'s current affinity mask",
-    case string:tokens(Data, ":") of
+    case string:lexemes(Data, ":") of
 	[Exp, DirtyAffinityStr] ->
-	    AffinityStr = string:strip(string:strip(DirtyAffinityStr,
-						    both, $ ),
-				       both, $\n),
+	    AffinityStr = string:trim(DirtyAffinityStr),
 	    case catch erlang:list_to_integer(AffinityStr, 16) of
 		Affinity when is_integer(Affinity) ->
 		    Affinity;
@@ -1083,7 +1083,6 @@ sbt_test(Config, CpuTCmd, ClBt, Bt, LP) ->
     ok.
 
 scheduler_threads(Config) when is_list(Config) ->
-    SmpSupport = erlang:system_info(smp_support),
     {Sched, SchedOnln, _} = get_sstate(Config, ""),
     %% Configure half the number of both the scheduler threads and
     %% the scheduler threads online.
@@ -1095,10 +1094,7 @@ scheduler_threads(Config) when is_list(Config) ->
     %% setting using +SP to 50% scheduler threads and 25% scheduler
     %% threads online. The result should be 2x scheduler threads and
     %% 1x scheduler threads online.
-    TwiceSched = case SmpSupport of
-                     false -> 1;
-                     true -> Sched*2
-                 end,
+    TwiceSched = Sched*2,
     FourSched = integer_to_list(Sched*4),
     FourSchedOnln = integer_to_list(SchedOnln*4),
     CombinedCmd1 = "+S "++FourSched++":"++FourSchedOnln++" +SP50:25",
@@ -1121,8 +1117,8 @@ scheduler_threads(Config) when is_list(Config) ->
 	    ResetCmd = "+S "++FourSched++":"++FourSchedOnln++" +S 0:0",
 	    {LProc, LProcAvail, _} = get_sstate(Config, ResetCmd),
 	    %% Test negative +S settings, but only for SMP-enabled emulators
-	    case {SmpSupport, LProc > 1, LProcAvail > 1} of
-		{true, true, true} ->
+	    case {LProc > 1, LProcAvail > 1} of
+		{true, true} ->
 		    SchedMinus1 = LProc-1,
 		    SchedOnlnMinus1 = LProcAvail-1,
 		    {SchedMinus1, SchedOnlnMinus1, _} = get_sstate(Config, "+S -1"),
@@ -1157,9 +1153,6 @@ dirty_scheduler_threads_test(Config) ->
     ok.
 
 dirty_schedulers_online_test() ->
-    dirty_schedulers_online_test(erlang:system_info(smp_support)).
-dirty_schedulers_online_test(false) -> ok;
-dirty_schedulers_online_test(true) ->
     dirty_schedulers_online_smp_test(erlang:system_info(schedulers_online)).
 dirty_schedulers_online_smp_test(SchedOnln) when SchedOnln < 4 -> ok;
 dirty_schedulers_online_smp_test(SchedOnln) ->
@@ -1453,6 +1446,79 @@ sst5_loop(N) ->
     erlang:system_flag(multi_scheduling, unblock_normal),
     sst5_loop(N-1).
 
+poll_threads(Config) when is_list(Config) ->
+    {Conc, PollType, KP} = get_ioconfig(Config),
+    {Sched, SchedOnln, _} = get_sstate(Config, ""),
+
+    [1, 1] = get_ionum(Config,"+IOt 2 +IOp 2"),
+    [1, 1, 1, 1, 1] = get_ionum(Config,"+IOt 5 +IOp 5"),
+
+    [1, 1] = get_ionum(Config, "+S 2 +IOPt 100 +IOPp 100"),
+
+    if
+        Conc ->
+            [5] = get_ionum(Config,"+IOt 5 +IOp 1"),
+            [3, 2] = get_ionum(Config,"+IOt 5 +IOp 2"),
+            [2, 2, 2, 2, 2] = get_ionum(Config,"+IOt 10 +IOPp 50"),
+
+            [2] = get_ionum(Config, "+S 2 +IOPt 100"),
+            [4] = get_ionum(Config, "+S 4 +IOPt 100"),
+            [4] = get_ionum(Config, "+S 4:2 +IOPt 100"),
+            [4, 4] = get_ionum(Config, "+S 8 +IOPt 100 +IOPp 25"),
+
+            fail = get_ionum(Config, "+IOt 1 +IOp 2"),
+
+            ok;
+        not Conc ->
+            [1, 1, 1, 1, 1] = get_ionum(Config,"+IOt 5 +IOp 1"),
+            [1, 1, 1, 1, 1] = get_ionum(Config,"+IOt 5 +IOp 2"),
+            [1, 1, 1, 1, 1, 1, 1, 1, 1, 1] = get_ionum(Config,"+IOt 10 +IOPp 50"),
+
+            [1, 1] = get_ionum(Config, "+S 2 +IOPt 100"),
+            [1, 1, 1, 1] = get_ionum(Config, "+S 4 +IOPt 100"),
+            [1, 1, 1, 1] = get_ionum(Config, "+S 4:2 +IOPt 100"),
+            [1, 1, 1, 1, 1, 1, 1, 1] = get_ionum(Config, "+S 8 +IOPt 100 +IOPp 25"),
+
+            [1] = get_ionum(Config, "+IOt 1 +IOp 2"),
+
+            ok
+    end,
+
+    fail = get_ionum(Config, "+IOt 1 +IOPp 101"),
+    fail = get_ionum(Config, "+IOt 0"),
+    fail = get_ionum(Config, "+IOPt 101"),
+
+    ok.
+
+get_ioconfig(Config) ->
+    [PS | _] = get_iostate(Config, ""),
+    {proplists:get_value(concurrent_updates, PS),
+     proplists:get_value(primary, PS),
+     proplists:get_value(kernel_poll, PS)}.
+
+get_ionum(Config, Cmd) ->
+    case get_iostate(Config, Cmd) of
+        fail -> fail;
+        PSs ->
+            lists:reverse(
+              lists:sort(
+                [proplists:get_value(poll_threads, PS) || PS <- PSs]))
+    end.
+
+get_iostate(Config, Cmd)->
+    case start_node(Config, Cmd) of
+        {ok, Node} ->
+            [IOStates] = mcall(Node,[fun () ->
+                                             erlang:system_info(check_io)
+                                     end]),
+            IO = [IOState || IOState <- IOStates,
+                             proplists:get_value(fallback, IOState) == false],
+            stop_node(Node),
+            IO;
+        {error,timeout} ->
+            fail
+    end.
+
 reader_groups(Config) when is_list(Config) ->
     %% White box testing. These results are correct, but other results
     %% could be too...
@@ -1777,18 +1843,24 @@ mcall(Node, Funs) ->
     Parent = self(),
     Refs = lists:map(fun (Fun) ->
                              Ref = make_ref(),
-                             spawn_link(Node,
-                                        fun () ->
-                                                Res = Fun(),
-                                                unlink(Parent),
-                                                Parent ! {Ref, Res}
-                                        end),
-                             Ref
+                             Pid = spawn(Node,
+                                         fun () ->
+                                                 Res = Fun(),
+                                                 unlink(Parent),
+                                                 Parent ! {Ref, Res}
+                                         end),
+                             MRef = erlang:monitor(process, Pid),
+                             {Ref, MRef}
                      end, Funs),
-    lists:map(fun (Ref) ->
+    lists:map(fun ({Ref, MRef}) ->
                       receive
                           {Ref, Res} ->
-                              Res
+                              receive
+                                  {'DOWN',MRef,_,_,_} ->
+                                      Res
+                              end;
+                          {'DOWN',MRef,_,_,Reason} ->
+                              Reason
                       end
               end, Refs).
 
diff --git a/erts/emulator/test/signal_SUITE.erl b/erts/emulator/test/signal_SUITE.erl
index f1d11d1814..61a8617165 100644
--- a/erts/emulator/test/signal_SUITE.erl
+++ b/erts/emulator/test/signal_SUITE.erl
@@ -139,71 +139,66 @@ pending_exit_gc(Config) when is_list(Config) ->
     pending_exit_test(self(), gc).
 
 pending_exit_test(From, Type) ->
-    case catch erlang:system_info(smp_support) of
-        true ->
-            OTE = process_flag(trap_exit, true),
-            Ref = make_ref(),
-            Master = self(),
-            ExitBySignal = case Type of
-                               gc ->
-                                   lists:duplicate(10000,
-                                                   exit_by_signal);
-                               _ ->
-                                   exit_by_signal
-                           end,
-            Pid = spawn_link(
-                    fun () ->
-                            receive go -> ok end,
-                            false = have_pending_exit(),
-                            exit = fake_exit(From,
-                                             self(),
-                                             ExitBySignal),
-                            true = have_pending_exit(),
-                            Master ! {self(), Ref, Type},
-                            case Type of
-                                gc ->
-                                    force_gc(),
-                                    erlang:yield();
-                                unlink ->
-                                    unlink(From);
-                                trap_exit ->
-                                    process_flag(trap_exit, true);
-                                'receive' ->
-                                    receive _ -> ok
-                                    after 0 -> ok
-                                    end;
-                                exit ->
-                                    ok
-                            end,
-                            exit(exit_by_myself)
-                    end),
-            Mon = erlang:monitor(process, Pid),
-            Pid ! go,
-            Reason = receive
-                         {'DOWN', Mon, process, Pid, R} ->
-                             receive
-                                 {Pid, Ref, Type} ->
-                                     ok
-                             after 0 ->
-                                       ct:fail(premature_exit)
-                             end,
-                             case Type of
-                                 exit ->
-                                     exit_by_myself = R;
-                                 _ ->
-                                     ExitBySignal = R
-                             end
+    OTE = process_flag(trap_exit, true),
+    Ref = make_ref(),
+    Master = self(),
+    ExitBySignal = case Type of
+                       gc ->
+                           lists:duplicate(10000,
+                                           exit_by_signal);
+                       _ ->
+                           exit_by_signal
+                   end,
+    Pid = spawn_link(
+            fun () ->
+                    receive go -> ok end,
+                    false = have_pending_exit(),
+                    exit = fake_exit(From,
+                                     self(),
+                                     ExitBySignal),
+                    true = have_pending_exit(),
+                    Master ! {self(), Ref, Type},
+                    case Type of
+                        gc ->
+                            force_gc(),
+                            erlang:yield();
+                        unlink ->
+                            unlink(From);
+                        trap_exit ->
+                            process_flag(trap_exit, true);
+                        'receive' ->
+                            receive _ -> ok
+                            after 0 -> ok
+                            end;
+                        exit ->
+                            ok
+                    end,
+                    exit(exit_by_myself)
+            end),
+    Mon = erlang:monitor(process, Pid),
+    Pid ! go,
+    Reason = receive
+                 {'DOWN', Mon, process, Pid, R} ->
+                     receive
+                         {Pid, Ref, Type} ->
+                             ok
+                     after 0 ->
+                             ct:fail(premature_exit)
                      end,
-            receive
-                {'EXIT', Pid, R2} ->
-                    Reason = R2
-            end,
-            process_flag(trap_exit, OTE),
-            ok,
-            {comment, "Test only valid with current SMP emulator."};
-        _ ->
-            {skipped, "SMP support not enabled. Test only valid with current SMP emulator."}
-    end.
+                     case Type of
+                         exit ->
+                             exit_by_myself = R;
+                         _ ->
+                             ExitBySignal = R
+                     end
+             end,
+    receive
+        {'EXIT', Pid, R2} ->
+            Reason = R2
+    end,
+    process_flag(trap_exit, OTE),
+    ok,
+    {comment, "Test only valid with current SMP emulator."}.
 
 
 
diff --git a/erts/emulator/test/smoke_test_SUITE.erl b/erts/emulator/test/smoke_test_SUITE.erl
index 41bb07b84c..adc6f56c06 100644
--- a/erts/emulator/test/smoke_test_SUITE.erl
+++ b/erts/emulator/test/smoke_test_SUITE.erl
@@ -88,11 +88,9 @@ native_atomics(Config) when is_list(Config) ->
     {value,{NA32Key, NA32, _}} = lists:keysearch(NA32Key, 1, EthreadInfo),
     {value,{NA64Key, NA64, _}} = lists:keysearch(NA64Key, 1, EthreadInfo),
     {value,{DWNAKey, DWNA, _}} = lists:keysearch(DWNAKey, 1, EthreadInfo),
-    case {erlang:system_info(build_type), erlang:system_info(smp_support), NA32, NA64, DWNA} of
-	{opt, true, "no", "no", _} ->
+    case {erlang:system_info(build_type), NA32, NA64, DWNA} of
+	{opt, "no", "no", _} ->
 	    ct:fail(optimized_smp_runtime_without_native_atomics);
-	{_, false, "no", "no", _} ->
-	    {comment, "No native atomics"};
 	_ ->
 	    {comment,
 	     NA32 ++ " 32-bit, "
diff --git a/erts/emulator/test/statistics_SUITE.erl b/erts/emulator/test/statistics_SUITE.erl
index 40cc940a94..029a6de897 100644
--- a/erts/emulator/test/statistics_SUITE.erl
+++ b/erts/emulator/test/statistics_SUITE.erl
@@ -638,9 +638,7 @@ msacc(Config) ->
                         (aux, 0) ->
                              %% aux will be zero if we do not have smp support
                              %% or no async threads
-                             case erlang:system_info(smp_support) orelse
-                                  erlang:system_info(thread_pool_size) > 0
-                             of
+                             case erlang:system_info(thread_pool_size) > 0 of
                                  false ->
                                      ok;
                                  true ->
@@ -676,6 +674,16 @@ msacc_test(TmpFile) ->
     ets:insert(Tid, {1, hello}),
     ets:delete(Tid),
 
+    %% Check some IO
+    {ok, L} = gen_tcp:listen(0, [{active, true},{reuseaddr,true}]),
+    {ok, Port} = inet:port(L),
+    Pid = spawn(fun() ->
+                        {ok, S} = gen_tcp:accept(L),
+                        (fun F() -> receive M -> F() end end)()
+                end),
+    {ok, C} = gen_tcp:connect("localhost", Port, []),
+    [begin gen_tcp:send(C,"hello"),timer:sleep(1) end || _ <- lists:seq(1,100)],
+
     %% Collect some garbage
     [erlang:garbage_collect() || _ <- lists:seq(1,100)],
 
diff --git a/erts/emulator/test/system_info_SUITE.erl b/erts/emulator/test/system_info_SUITE.erl
index 56522039da..fdf4aab24d 100644
--- a/erts/emulator/test/system_info_SUITE.erl
+++ b/erts/emulator/test/system_info_SUITE.erl
@@ -308,9 +308,9 @@ memory_test(_Config) ->
 
     mem_workers_call(MWs,
 		     fun () ->
-			     list_to_atom("an ugly atom "++integer_to_list(erlang:system_info(scheduler_id))),
-			     list_to_atom("another ugly atom "++integer_to_list(erlang:system_info(scheduler_id))),
-			     list_to_atom("yet another ugly atom "++integer_to_list(erlang:system_info(scheduler_id)))
+			     _ = list_to_atom("an ugly atom "++integer_to_list(erlang:system_info(scheduler_id))),
+			     _ = list_to_atom("another ugly atom "++integer_to_list(erlang:system_info(scheduler_id))),
+			     _ = list_to_atom("yet another ugly atom "++integer_to_list(erlang:system_info(scheduler_id)))
 		     end, []),
     cmp_memory(MWs, "new atoms"),
 
diff --git a/erts/emulator/test/system_profile_SUITE.erl b/erts/emulator/test/system_profile_SUITE.erl
index 9b678fcff9..c9be54f668 100644
--- a/erts/emulator/test/system_profile_SUITE.erl
+++ b/erts/emulator/test/system_profile_SUITE.erl
@@ -146,9 +146,8 @@ do_runnable_ports({TsType, TsTypeFlag}, Config) ->
 
 %% Tests system_profiling with scheduler.
 scheduler(Config) when is_list(Config) ->
-    case {erlang:system_info(smp_support), erlang:system_info(schedulers_online)} of
-	{false,_} -> {skipped, "No need for scheduler test when smp support is disabled."};
-	{_,    1} -> {skipped, "No need for scheduler test when only one scheduler online."};
+    case erlang:system_info(schedulers_online) of
+	1 -> {skipped, "No need for scheduler test when only one scheduler online."};
 	_ ->
 	    Nodes = 10,
 	    lists:foreach(fun (TsType) ->
diff --git a/erts/emulator/test/tuple_SUITE.erl b/erts/emulator/test/tuple_SUITE.erl
index 79b681b4d1..baf41180e0 100644
--- a/erts/emulator/test/tuple_SUITE.erl
+++ b/erts/emulator/test/tuple_SUITE.erl
@@ -134,6 +134,13 @@ t_element(Config) when is_list(Config) ->
     {'EXIT', {badarg, _}} = (catch element(1, id(42))),
     {'EXIT', {badarg, _}} = (catch element(id(1.5), id({a,b}))),
 
+    %% Make sure that the loader does not reject the module when
+    %% huge literal index values are used.
+    {'EXIT', {badarg, _}} = (catch element((1 bsl 24)-1, id({a,b,c}))),
+    {'EXIT', {badarg, _}} = (catch element(1 bsl 24, id({a,b,c}))),
+    {'EXIT', {badarg, _}} = (catch element(1 bsl 32, id({a,b,c}))),
+    {'EXIT', {badarg, _}} = (catch element(1 bsl 64, id({a,b,c}))),
+
     ok.
 
 get_elements([Element|Rest], Tuple, Pos) ->
diff --git a/erts/emulator/test/z_SUITE.erl b/erts/emulator/test/z_SUITE.erl
index feea7432a9..ac3df8bfbf 100644
--- a/erts/emulator/test/z_SUITE.erl
+++ b/erts/emulator/test/z_SUITE.erl
@@ -330,7 +330,7 @@ display_check_io(ChkIo) ->
     ok.
 
 get_check_io_info() ->
-    ChkIo = erlang:system_info(check_io),
+    ChkIo = driver_SUITE:get_check_io_total(erlang:system_info(check_io)),
     PendUpdNo = case lists:keysearch(pending_updates, 1, ChkIo) of
 		    {value, {pending_updates, PendNo}} ->
 			PendNo;
diff --git a/erts/emulator/utils/beam_emu_vars b/erts/emulator/utils/beam_emu_vars
new file mode 100755
index 0000000000..c798a4dada
--- /dev/null
+++ b/erts/emulator/utils/beam_emu_vars
@@ -0,0 +1,122 @@
+#!/usr/bin/perl -w
+use strict;
+
+# Analyse beam_emu.s and try to find out the registers
+# used for the important variables in process_main().
+#
+# Works for .s files from clang or gcc. For gcc, the -fverbose-asm
+# option must be used.
+#
+# Example:
+#
+# $ beam-emu-vars -vars 'c_p E HTOP FCALLS I reg freg' beam_emu.s
+# E: %r13
+# FCALLS: %rcx:98 %rax:88 16(%rsp):50 %rdi:6
+# HTOP: %r10:382 64(%rsp):88 72(%rsp):9 24(%rsp):7 %rcx:6 %r15:6 80(%rsp):3 88(%rsp):2
+# I: %rbx
+# c_p: %rbp
+# freg: 48(%rsp):11 %rcx:8 %rdi:5 %rax:4
+# reg: %r12
+#
+# That means that E, I, c_p, reg seems to be assigned to permanent registers.
+# HTOP seems to be assigned %r10, but it is saved to a scratch location
+# before any function calls. FCALLS and freg seems to be saved in a location on
+# the stack and loaded into a register when used.
+#
+# The exit status will be 0 if all variables are assigned to registers (most of
+# the time), and 1 if one or more variables are assigned to a stack location.
+
+my $vars = 'c_p E FCALLS freg HTOP I reg';
+
+while (@ARGV and $ARGV[0] =~ /^-(.*)/) {
+    $_ = $1;
+    shift;
+    ($vars = shift), next if /^vars/;
+    die "$0: Bad option: -$_\n";
+}
+
+my @vars = split(" ", $vars);
+my %vars;
+@vars{@vars} = @vars;
+
+my $inside;
+my %count;
+
+if (@ARGV != 1) {
+    usage();
+}
+
+while (<>) {
+    if (!$inside && /[.]globl\s*_?process_main/) {
+	$inside = 1;
+    } elsif ($inside && /[.]globl/) {
+	last;
+    }
+    if ($inside) {
+	if (/##DEBUG_VALUE:\s*process_main:([A-Za-z]*)\s*<-\s*(.*)/) {
+	    # clang
+	    my($var,$reg) = ($1,$2);
+	    next if $reg =~ /^[-\d]+$/; # Ignore if number.
+	    $count{$var}->{$reg}++ if $vars{$var};
+	    next;
+	}
+
+	# Parse gcc verbose arguments. Comments are marked with
+	# one '#' (clang marks its comments with two '#').
+	my($src,$dst,$comment) = /movq\s+([^#]+), ([^#]+)#(?!#)\s*(.*)/;
+	next unless $comment;
+	$dst =~ s/\s*$//;
+	my($vsrc,$vdst) = split /,/, $comment, 2;
+	$vdst =~ s/^\s//;
+	update_count(\%count, $vsrc, $src);
+	update_count(\%count, $vdst, $dst);
+	if ($vars{$vdst} and $vsrc eq '%sfp') {
+	    $count{$vdst}->{$src}++;
+	}
+    }
+}
+
+my @first;
+
+OUTER:
+for my $var (sort keys %count) {
+    my $total = 0;
+
+    foreach my $reg (keys %{$count{$var}}) {
+	$total += $count{$var}->{$reg}++;
+    }
+
+    foreach my $reg (keys %{$count{$var}}) {
+	if ($count{$var}->{$reg} > 0.9*$total) {
+	    print "$var: $reg\n";
+	    push @first, $var;
+	    next OUTER;
+	}
+    }
+
+    my @r;
+    foreach my $reg (keys %{$count{$var}}) {
+	push @r, $reg;
+    }
+    @r = sort { $count{$var}->{$b} <=> $count{$var}->{$a} } @r;
+    @r = map { "$_:$count{$var}->{$_}" } @r;
+    push @first, $r[0];
+    print "$var: ", join(' ', @r), "\n";
+}
+
+foreach (@first) {
+    exit 1 if /%rsp/;
+}
+exit 0;
+
+sub update_count {
+    my($count_ref,$var,$reg) = @_;
+    return unless $vars{$var};
+    ${${$count_ref}{$var}}{$reg}++;
+}
+
+sub usage {
+    die qq[usage: beam_emu_vars [ -vars "var1 var2..." ] <filename>.s\n\n] .
+	"The exit status is 0 if all variables are assigned to registers,\n" .
+	"and 1 if one or more variables are allocated to a stack location.\n";
+}
diff --git a/erts/emulator/utils/beam_makeops b/erts/emulator/utils/beam_makeops
index 0a30553f71..da994fae3e 100755
--- a/erts/emulator/utils/beam_makeops
+++ b/erts/emulator/utils/beam_makeops
@@ -19,45 +19,40 @@
 # %CopyrightEnd%
 #
 use strict;
-use vars qw($BEAM_FORMAT_NUMBER);
+use vars qw($BEAM_FORMAT_NUMBER $GC_REGEXP);
+use constant COLD => 0;
+use constant WARM => 1;
+use constant HOT => 2;
+
+# Instructions for packing
+use constant PACK_JUMP => 1;
+use constant PACK_IN_INSTR_WORD => 2;
+use constant PACK_OPT_IN_INSTR_WORD => 4;
+
+# Packing commands
+use constant PACK_CMD_TIGHTEST => '1';
+use constant PACK_CMD_TIGHT => '2';
+use constant PACK_CMD_LOOSE => '3';
+use constant PACK_CMD_WIDE => '4';
 
 $BEAM_FORMAT_NUMBER = undef;
+$GC_REGEXP = undef;
 
 my $target = \&emulator_output;
 my $outdir = ".";		# Directory for output files.
 my $verbose = 0;
-my $hot = 1;
+my $hotness = 1;
 my $num_file_opcodes = 0;
 my $wordsize = 32;
-my %defs;			# Defines (from command line).
+my $code_pointers_are_short = 0; # Whether code pointers (to C code) are short.
+my $code_model = 'unknown';
+my %defs;                        # Defines (from command line).
 
 # This is shift counts and mask for the packer.
 my $WHOLE_WORD = '';
-my @pack_instr;
-my @pack_shift;
-my @pack_mask;
 
-$pack_instr[2] = ['6', 'i'];
-$pack_instr[3] = ['0', '0', 'i'];
-$pack_instr[4] = ['6', '6', '6', 'i']; # Only for 64 bit wordsize
-
-$pack_shift[2] = ['0', 'BEAM_LOOSE_SHIFT'];
-$pack_shift[3] = ['0', 'BEAM_TIGHT_SHIFT', '(2*BEAM_TIGHT_SHIFT)'];
-$pack_shift[4] = ['0', 'BEAM_LOOSE_SHIFT', # Only for 64 bit wordsize
-		  '(2*BEAM_LOOSE_SHIFT)',
-		  '(3*BEAM_LOOSE_SHIFT)'];
-
-$pack_mask[2]  = ['BEAM_LOOSE_MASK', $WHOLE_WORD];
-$pack_mask[3]  = ['BEAM_TIGHT_MASK', 'BEAM_TIGHT_MASK', 'BEAM_TIGHT_MASK'];
-$pack_mask[4]  = ['BEAM_LOOSE_MASK', # Only for 64 bit wordsize
-		  'BEAM_LOOSE_MASK',
-		  'BEAM_LOOSE_MASK',
-		  $WHOLE_WORD];
-
-# Mapping from packagable arguments to number of packed arguments per
-# word.  Initialized after the wordsize is known.
-
-my @args_per_word;
+my @basic_pack_options = (0);
+my @extended_pack_options = @basic_pack_options;
 
 # There are two types of instructions: generic and specific.
 # The generic instructions are those generated by the Beam compiler.
@@ -83,6 +78,14 @@ my %num_specific;
 my %gen_to_spec;
 my %specific_op;
 
+# The following hashes are used for error checking.
+my %print_name;
+my %specific_op_arity;
+
+# Information about each specific operator. Key is the print name (e.g. get_list_xxy).
+# Value is a hash.
+my %spec_op_info;
+
 my %gen_arity;
 my @gen_arity;
 
@@ -91,17 +94,22 @@ my @op_to_name;
 
 my @obsolete;
 
-my %macro;
-my %macro_flags;
+# Instructions and micro instructions implemented in C.
+my %c_code;                     # C code block, location, arguments.
+my %c_code_used;                # Used or not.
 
-my %hot_code;
-my %cold_code;
+# Definitions for instructions combined from micro instructions.
+my %combined_instrs;
+
+my @generated_code;             # Generated code.
+my %sort_order;
 
 my @unnumbered_generic;
 my %unnumbered;
 
 my %is_transformed;
 
+
 #
 # Pre-processor.
 #
@@ -128,7 +136,10 @@ my $loader_types = "nprvlqo";
 my $genop_types = $compiler_types . $loader_types;
 
 #
-# Defines the argument types and their loaded size assuming no packing.
+# Define the operand types and their loaded size assuming no packing.
+#
+# Those are the types that can be used in the definition of a specific
+# instruction.
 #
 my %arg_size = ('r' => 0,	# x(0) - x register zero
 		'x' => 1,	# x(N), N > 0 - x register
@@ -138,23 +149,48 @@ my %arg_size = ('r' => 0,	# x(0) - x register zero
 		'n' => 0,	# NIL (implicit)
 		'c' => 1,	# tagged constant (integer, atom, nil)
 		's' => 1,	# tagged source; any of the above
+                'S' => 1,       # tagged source register (x or y)
 		'd' => 1,	# tagged destination register (r, x, y)
 		'f' => 1,	# failure label
 		'j' => 1,	# either 'f' or 'p'
 		'e' => 1,	# pointer to export entry
 		'L' => 0,	# label
-		'I' => 1,	# untagged integer
-		't' => 1,	# untagged integer -- can be packed
+		't' => 1,	# untagged integer (12 bits) -- can be packed
+		'I' => 1,	# untagged integer (32 bits) -- can be packed
+                'W' => 1,       # untagged integer/pointer (one word)
 		'b' => 1,	# pointer to bif
 		'A' => 1,	# arity value
 		'P' => 1,	# byte offset into tuple or stack
 		'Q' => 1,	# like 'P', but packable
-		'h' => 1,	# character
+		'h' => 1,	# character (not used)
 		'l' => 1,	# float reg
 		'q' => 1,	# literal term
 	     );
 
 #
+# Define the types that may be used in a transformation rule.
+#
+# %pattern_type defines the types that may be used in a pattern
+# on the left side.
+#
+# %construction_type defines the types that may be used when
+# constructing a new instruction on the right side (a subset of
+# the pattern types that are possible to construct).
+#
+my $pattern_types = "acdfjilnopqsuxy";
+my %pattern_type;
+@pattern_type{split("", $pattern_types)} = (1) x length($pattern_types);
+
+my %construction_type;
+foreach my $type (keys %pattern_type) {
+    $construction_type{$type} = 1
+        if index($genop_types, $type) >= 0;
+}
+foreach my $makes_no_sense ('f', 'j', 'o', 'p', 'q') {
+    delete $construction_type{$makes_no_sense};
+}
+
+#
 # Generate bits.
 #
 my %type_bit;
@@ -186,16 +222,17 @@ sub define_type_bit {
     define_type_bit('s', $type_bit{'d'} | $type_bit{'i'} |
 		    $type_bit{'a'} | $type_bit{'n'} |
 		    $type_bit{'q'});
+    define_type_bit('S', $type_bit{'d'});
     define_type_bit('j', $type_bit{'f'} | $type_bit{'p'});
 
-    # Aliases (for matching purposes).
-    define_type_bit('I', $type_bit{'u'});
+    # Aliases of 'u'.  Those specify how to load the operand and
+    # what kind of packing can be done.
     define_type_bit('t', $type_bit{'u'});
+    define_type_bit('I', $type_bit{'u'});
+    define_type_bit('W', $type_bit{'u'});
     define_type_bit('A', $type_bit{'u'});
     define_type_bit('L', $type_bit{'u'});
     define_type_bit('b', $type_bit{'u'});
-    define_type_bit('N', $type_bit{'u'});
-    define_type_bit('U', $type_bit{'u'});
     define_type_bit('e', $type_bit{'u'});
     define_type_bit('P', $type_bit{'u'});
     define_type_bit('Q', $type_bit{'u'});
@@ -222,6 +259,12 @@ $match_engine_ops{'TOP_fail'} = 1;
 	sanity("tag '$tag': primitive tags must be named with lowercase letters")
 	    unless $tag =~ /^[a-z]$/;
     }
+
+    foreach my $tag (keys %arg_size) {
+        defined $type_bit{$tag} or
+            sanity("the tag '$tag' has a size in %arg_size, " .
+                   "but has no defined bit pattern");
+    }
 }
 
 #
@@ -235,32 +278,75 @@ while (@ARGV && $ARGV[0] =~ /^-(.*)/) {
     ($target = \&compiler_output), next if /^compiler/;
     ($outdir = shift), next if /^outdir/;
     ($wordsize = shift), next if /^wordsize/;
+    ($code_model = shift), next if /^code-model/;
     ($verbose = 1), next if /^v/;
     ($defs{$1} = $2), next if /^D(\w+)=(\w+)/;
     die "$0: Bad option: -$_\n";
 }
 
+if ($wordsize == 32) {
+    $defs{'ARCH_32'} = 1;
+    $defs{'ARCH_64'} = 0;
+} elsif ($wordsize == 64) {
+    $defs{'ARCH_32'} = 0;
+    $defs{'ARCH_64'} = 1;
+    $code_pointers_are_short = $code_model eq 'small';
+}
+
 #
-# Initialize number of arguments per packed word.
+# Initialize pack options.
 #
 
-$args_per_word[2] = 2;
-$args_per_word[3] = 3;
-$args_per_word[4] = 2;
-$args_per_word[5] = 3;
-$args_per_word[6] = 3;
-
 if ($wordsize == 64) {
-    $pack_mask[3] = ['BEAM_TIGHT_MASK', 'BEAM_TIGHT_MASK', $WHOLE_WORD];
-    $args_per_word[4] = 4;
+    @basic_pack_options = (0,PACK_JUMP);
+    @extended_pack_options = @basic_pack_options;
+    if ($code_pointers_are_short) {
+        foreach (@basic_pack_options) {
+            push @extended_pack_options, $_ | PACK_IN_INSTR_WORD;
+        }
+    }
+}
+
+#
+# Add placeholders for built-in macros.
+#
+
+my %predef_macros =
+    (OPERAND_POSITION => ['Expr'],
+     IF => ['Expr','IfTrue','IfFalse'],
+     REFRESH_GEN_DEST => [],
+    );
+foreach my $name (keys %predef_macros) {
+    my @args = @{$predef_macros{$name}};
+    my $body = join(':', map { '$' . $_ } @args);
+    $c_code{$name} = [$body,"built-in macro",@args],
+    $c_code_used{$name} = 1;
 }
 
 #
 # Parse the input files.
 #
 
+my $in_c_code = '';
+my $c_code_block;
+my $c_code_loc;
+my @c_args;
+
 while (<>) {
     my($op_num);
+    if ($in_c_code) {
+        if (/^\}/) {
+            my $name = $in_c_code;
+            my $block = $c_code_block;
+            $in_c_code = '';
+            $block =~ s/^    //mg;
+            chomp $block;
+            $c_code{$name} = [$block,$c_code_loc,@c_args];
+        } else {
+            $c_code_block .= $_;
+        }
+        next;
+    }
     chomp;
     if (s/\\$//) {
 	$_ .= <>;
@@ -268,6 +354,7 @@ while (<>) {
     }
     next if /^\s*$/;
     next if /^\#/;
+    next if m@^//@;
 
     #
     # Handle %if.
@@ -310,36 +397,24 @@ while (<>) {
     #
     if (/^([\w_][\w\d_]+)=(.*)/) {
 	no strict 'refs';
-	my($name) = $1;
-	$$name = $2;
+	my $name = $1;
+        my $value = $2;
+        $value =~ s/;\s*$//;
+	$$name = $value;
 	next;
     }
 
     #
-    # Handle %hot/%cold.
+    # Handle %hot, %warm, and %cold.
     # 
     if (/^\%hot/) {
-	$hot = 1;
+	$hotness = HOT;
 	next;
+    } elsif (/^\%warm/) {
+	$hotness = WARM;
+        next;
     } elsif (/^\%cold/) {
-	$hot = 0;
-	next;
-    }
-    
-    #
-    # Handle macro definitions.
-    #
-    if (/^\%macro:(.*)/) {
-	my($op, $macro, @flags) = split(' ', $1);
-	defined($macro) and $macro =~ /^-/ and
-	    error("A macro must not start with a hyphen");
-	foreach (@flags) {
-	    /^-/ or error("Flags for macros should start with a hyphen");
-	}
-	error("Macro for '$op' is already defined")
-	    if defined $macro{$op};
-	$macro{$op} = $macro;
-	$macro_flags{$op} = join('', @flags);
+	$hotness = COLD;
 	next;
     }
 
@@ -352,6 +427,31 @@ while (<>) {
     }
 
     #
+    # Handle C code blocks.
+    #
+    if (/^(\w[\w.]*)\(([^\)]*)\)\s*{/) {
+        my $name = $1;
+        $in_c_code = $name;
+        $c_code_block = '';
+        @c_args = parse_c_args($2);
+        $c_code_loc = "$ARGV($.)";
+        if (defined $c_code{$name}) {
+            my $where = $c_code{$name}->[1];
+            error("$name: already defined at $where");
+        }
+        next;
+    }
+
+    #
+    # Handle definition of instructions in terms of
+    # micro instructions.
+    #
+    if (/^(\w+)\s*:=\s*([\w.]+)\s*;\s*$/) {
+        $combined_instrs{$1} = ["$ARGV($.)",$2];
+        next;
+    }
+
+    #
     # Parse off the number of the operation.
     #
     $op_num = undef;
@@ -394,15 +494,7 @@ while (<>) {
     # Parse specific instructions (only present in emulator/loader):
     #    Name Arg1 Arg2...
     #
-    my($name, @args) = split;
-    error("too many operands")
-	if @args > $max_spec_operands;
-    syntax_check($name, @args);
-    my $arity = @args;
-    if (defined $gen_opnum{$name,$arity} and $obsolete[$gen_opnum{$name,$arity}]) {
-	error("specific instructions may not be specified for obsolete instructions");
-    }
-    save_specific_ops($name, $arity, $hot, @args);
+    my($name,$arity) = parse_specific_op($_);
     if (defined $op_num) {
 	error("specific instructions must not be numbered");
     } elsif (!defined($gen_arity{$name}) && !defined($unnumbered{$name,$arity})) {
@@ -449,6 +541,18 @@ $num_file_opcodes = @gen_opname;
 &$target();
 
 #
+# Ensure that all C code implementations have been used.
+#
+{
+    my(@unused) = grep(!$c_code_used{$_}, keys %c_code);
+    foreach my $unused (@unused) {
+        my(undef,$where) = @{$c_code{$unused}};
+        warn "$where: $unused is unused\n";
+    }
+    die "\n" if @unused;
+}
+
+#
 # Produce output needed by the emulator/loader.
 #
 
@@ -458,6 +562,36 @@ sub emulator_output {
     my $key;			# Loop variable.
 
     #
+    # Generate code and meta information for all instructions.
+    #
+    foreach $key (keys %specific_op) {
+	foreach (@{$specific_op{$key}}) {
+	    my($name, $hotness, @args) = @$_;
+	    my $print_name = print_name($name, @args);
+
+	    my($size, $code, $pack_spec) = cg_basic(name => $name, args => \@args);
+	    if (defined $code) {
+                $code = "OpCase($print_name):\n$code";
+                push @generated_code, [$hotness,$code,($print_name)];
+	    }
+
+            # Note: Some of the information below will be modified
+            # for combined instructions.
+            my %info = ('size' => $size,
+                        'pack_spec' => $pack_spec,
+                        'adj' => 0,
+                        'args' => \@args);
+            $spec_op_info{$print_name} = \%info;
+	}
+    }
+
+    #
+    # Combine micro instruction into instruction blocks and generate
+    # code for them.
+    #
+    combine_micro_instructions();
+
+    #
     # Information about opcodes (beam_opcodes.c).
     #
     $name = "$outdir/beam_opcodes.c";
@@ -488,7 +622,7 @@ sub emulator_output {
     #
     # Generate code for specific ops.
     #
-    my($spec_opnum) = 0;
+    my $spec_opnum = 0;
     print "const OpEntry opc[] = {\n";
     foreach $key (sort keys %specific_op) {
 	$gen_to_spec{$key} = $spec_opnum;
@@ -503,40 +637,26 @@ sub emulator_output {
 	foreach (@{$specific_op{$key}}) {
 	    my($name, $hot, @args) = @{$_};
 	    my($sign) = join('', @args);
+            $sign =~ s/[?]//g;
 
 	    # The primitive types should sort before other types.
 
-	    my($sort_key) = $sign;
+	    my $sort_key = $sign;
 	    eval "\$sort_key =~ tr/$genop_types/./";
 	    $sort_key .= ":$sign";
-	    $items{$sort_key} = [$name, $hot, $sign, @args];
+            my $print_name = print_name($name, @args);
+	    $items{$sort_key} = $print_name;
 	}
 
 	#
 	# Now call the generator for the sorted result.
 	#
-	foreach (sort keys %items) {
-	    my($name, $hot, $sign, @args) = @{$items{$_}};
+	foreach my $sort_key (sort keys %items) {
+            my $print_name = $items{$sort_key};
+            my $info = $spec_op_info{$print_name};
+            my(@args) = @{$info->{'args'}};
+            @args = map { s/[?]$//; $_ } @args;
 	    my $arity = @args;
-	    my($instr) = "${name}_$sign";
-	    $instr =~ s/_$//;
-
-	    #
-	    # Call a generator to calculate size and generate macros
-	    # for the emulator.
-	    #
-	    my($size, $code, $pack) = basic_generator($name, $hot, @args);
-
-	    #
-	    # Save the generated $code for later.
-	    #
-	    if (defined $code) {
-		if ($hot) {
-		    push(@{$hot_code{$code}}, $instr);
-		} else {
-		    push(@{$cold_code{$code}}, $instr);
-		}
-	    }
 
 	    #
 	    # Calculate the bit mask which should be used to match this
@@ -558,7 +678,6 @@ sub emulator_output {
 	    }
 
 	    printf "/* %3d */  ", $spec_opnum;
-	    my $print_name = $sign ne '' ? "${name}_$sign" : $name;
 	    my $init = "{";
 	    my $sep = "";
 	    foreach (@bits) {
@@ -566,8 +685,12 @@ sub emulator_output {
 		$sep = ",";
 	    }
 	    $init .= "}";
-	    init_item($print_name, $init, $involves_r, $size, $pack, $sign);
-	    $op_to_name[$spec_opnum] = $instr;
+            my $adj = $info->{'adj'};
+            my $size = $info->{'size'};
+            my $pack_spec = $info->{'pack_spec'};
+            my $sign = join '', @args;
+	    init_item($print_name, $init, $involves_r, $size, $adj, $pack_spec, $sign);
+	    $op_to_name[$spec_opnum] = $print_name;
 	    $spec_opnum++;
 	}
     }
@@ -646,12 +769,19 @@ sub emulator_output {
 	print "#if !defined(ARCH_64)\n";
 	print qq[  #error "64-bit architecture assumed, but ARCH_64 not defined"\n];
 	print "#endif\n";
-	print "#define BEAM_WIDE_MASK 0xFFFFUL\n";
-	print "#define BEAM_LOOSE_MASK 0xFFFFUL\n";
-	print "#define BEAM_TIGHT_MASK 0xFFFFUL\n";
+        if ($code_pointers_are_short) {
+            print "#if !defined(CODE_MODEL_SMALL)\n";
+            print qq[  #error "small code model assumed, but CODE_MODEL_SMALL not defined"\n];
+            print "#endif\n";
+        }
+	print "#define BEAM_WIDE_MASK 0xFFFFFFFFull\n";
+	print "#define BEAM_LOOSE_MASK 0xFFFFull\n";
+	print "#define BEAM_TIGHT_MASK 0xFFFFull\n";
+	print "#define BEAM_TIGHTEST_MASK 0x3FFull\n";
 	print "#define BEAM_WIDE_SHIFT 32\n";
 	print "#define BEAM_LOOSE_SHIFT 16\n";
 	print "#define BEAM_TIGHT_SHIFT 16\n";
+	print "#define BEAM_TIGHTEST_SHIFT 10\n";
     }
     print "\n";
 
@@ -750,13 +880,24 @@ sub emulator_output {
     $name = "$outdir/beam_hot.h";
     open(STDOUT, ">$name") || die "Failed to open $name for writing: $!\n";
     comment('C');
-    print_code(\%hot_code);
+    print_code(HOT);
+
+    $name = "$outdir/beam_warm.h";
+    open(STDOUT, ">$name") || die "Failed to open $name for writing: $!\n";
+    comment('C');
+    print_code(WARM);
 
     $name = "$outdir/beam_cold.h";
     open(STDOUT, ">$name") || die "Failed to open $name for writing: $!\n";
     comment('C');
-    print_code(\%cold_code);
+    print_code(COLD);
+}
 
+sub print_name {
+    my($name,@args) = @_;
+    my $sign = join '', @args;
+    $sign =~ s/[?]//g;
+    $sign ne '' ? "${name}_$sign" : $name;
 }
 
 sub init_item {
@@ -784,29 +925,47 @@ sub q {
 }
 
 sub print_code {
-    my($ref) = @_;
-    my(%sorted);
-    my($key, $label);		# Loop variables.
-
-    foreach $key (keys %$ref) {
-	my($sort_key);
-	my($code) = '';
-	foreach $label (@{$ref->{$key}}) {
-	    $code .= "OpCase($label):\n";
-	    $sort_key = $label;
-	}
-	foreach (split("\n", $key)) {
-	    $code .= "    $_\n";
-	}
-	$code .= "\n";
-	$sorted{$sort_key} = $code;
+    my($include_hot) = @_;
+    my %sorted;
+
+    foreach my $ref (@generated_code) {
+        my($hot,$code,@labels) = @$ref;
+        next unless $hot == $include_hot;
+        my($sort_key) = @labels; # Use the first label as sort key.
+        $sorted{$sort_key} = $code;
     }
 
     foreach (sort keys %sorted) {
-	print $sorted{$_};
+	print_indented_code($sorted{$_});
     }
 }
 
+sub print_indented_code {
+    my(@code) = @_;
+
+    foreach my $chunk (@code) {
+        my $indent = 0;
+        foreach (split "\n", $chunk) {
+            s/^\s*//;
+            if (/\}/) {
+                $indent -= 2;
+            }
+            if ($_ eq '') {
+                print "\n";
+            } elsif (/^#/) {
+                print $_, "\n";
+            } else {
+                print ' ' x $indent, $_, "\n";
+            }
+            if (/\{/) {
+                $indent += 2;
+            }
+        }
+        print "\n";
+    }
+}
+
+
 #
 # Produce output needed by the compiler back-end (assembler).
 #
@@ -857,40 +1016,82 @@ sub compiler_output {
 }
 
 #
-# Check an operation for validity.
+# Parse and store a specific operation.
 #
-sub syntax_check {
-    my($name, @args) = @_;
-    my($i);
+sub parse_specific_op {
+    my($name, @args) = split " ", shift;
+    my $arity = @args;
 
+    # Check for various errors.
     error("Bad opcode name '$name'")
 	unless $name =~ /^[a-z][\w\d_]*$/;
-    for ($i = 0; $i < @args; $i++) {
-        foreach my $type (split(//, $args[$i])) {
+    error("too many operands")
+	if @args > $max_spec_operands;
+    for (my $i = 0; $i < $arity; $i++) {
+        my $arg = $args[$i];
+        $arg =~ s/[?]$//;
+        foreach my $type (split(//, $arg)) {
             error("Argument " . ($i+1) . ": invalid type '$type'")
                 unless defined $arg_size{$type};
         }
     }
-}
-
-sub save_specific_ops {
-    my($name,$arity,$hot,@args) = @_;
-    my(@res) = ("");
+    if (defined $gen_opnum{$name,$arity} and $obsolete[$gen_opnum{$name,$arity}]) {
+	error("specific instructions may not be specified for obsolete instructions");
+    }
 
+    # Expand operands with multiple types to multiple instructions.
+    # (For example, "get_list xy xy xy" will be expanded to six instructions.)
+    my @res = ([]);
     foreach my $arg (@args) {
-        my @new_res = ();
+        my @old_res = @res;
+        @res = ();
+        my $marker = ($arg =~ s/[?]$//) ? '?' : '';
         foreach my $type (split(//, $arg)) {
-            foreach my $args (@res) {
-                push @new_res, "$args$type";
+            foreach my $args_ref (@old_res) {
+                my @args = @$args_ref;
+                push @args, "$type$marker";
+                push @res, \@args;
             }
         }
-        @res = @new_res;
     }
+
+    # Store each specific instruction.
     my $key = "$name/$arity";
-    foreach my $args (@res) {
-        @args = split //, $args;
-        push @{$specific_op{$key}}, [$name,$hot,@args];
+    foreach my $args_ref (@res) {
+        @args = @$args_ref;
+        my $arity = @args;
+        my $loc = "$ARGV($.)";
+        if (defined $specific_op_arity{$name}) {
+            my($prev_arity,$loc) = @{$specific_op_arity{$name}};
+            if ($arity != $prev_arity) {
+                error("$name defined with arity $arity, " .
+                      "but previously defined with arity $prev_arity at $loc");
+            }
+        }
+        $specific_op_arity{$name} = [$arity,$loc];
+        my $print_name = print_name($name, @args);
+        if (defined $print_name{$print_name}) {
+            error("$name @args: already defined at " .
+                  $print_name{$print_name});
+        }
+        $print_name{$print_name} = $loc;
+        push @{$specific_op{$key}}, [$name,$hotness,@args];
+    }
+
+    # Done.
+    ($name,$arity);
+}
+
+sub parse_c_args {
+    local($_) = @_;
+    my @res;
+
+    while (s/^(\w[\w\d]*)\s*//) {
+        push @res, $1;
+        s/^,\s*// or last;
     }
+    $_ eq '' or error("garbage in argument list: $_");
+    @res;
 }
 
 sub error {
@@ -934,58 +1135,314 @@ sub comment {
 }
 
 #
-# Basic implementation of instruction in emulator loop
-# (assuming no packing).
+# Combine micro instruction into instruction blocks.
 #
+sub combine_micro_instructions {
+    my %groups;
+
+    # Sanity check, normalize micro instructions.
+    foreach my $instr (keys %combined_instrs) {
+        my $ref = $combined_instrs{$instr};
+        my($def_loc,$def) = @$ref;
+        my($group,@subs) = split /[.]/, $def;
+        my $arity = 0;
+        @subs = map { "$group.$_" } @subs;
+        foreach my $s (@subs) {
+            my $code = $c_code{$s};
+            defined $code or
+                error("$def_loc: no definition of $s");
+            $c_code_used{$s} = 1;
+            my(undef,undef,@c_args) = @{$code};
+            $arity += scalar(@c_args);
+        }
+        push @{$groups{$group}}, [$instr,$arity,@subs];
+    }
 
-sub basic_generator {
-    my($name, $hot, @args) = @_;
-    my($size) = 0;
-    my($macro) = '';
-    my($flags) = '';
-    my(@f);
-    my(@f_types);
-    my($fail_type);
-    my($prefix) = '';
-    my($tmp_arg_num) = 1;
-    my($pack_spec) = '';
-    my($var_decls) = '';
-    my($i);
-    my($no_prefetch) = 0;
+    # Now generate code for each group.
+    foreach my $group (sort keys %groups) {
+        my($hotness,$code,@labels) =
+            combine_instruction_group($group, @{$groups{$group}});
+        push @generated_code, [$hotness,$code,@labels];
+    }
+}
 
-    # The following argument types should be included as macro arguments.
-    my(%incl_arg) = ('c' => 1,
-		     'i' => 1,
-		     'a' => 1,
-		     'A' => 1,
-		     'N' => 1,
-		     'U' => 1,
-		     'I' => 1,
-		     't' => 1,
-		     'P' => 1,
-		     'Q' => 1,
-		     );
+sub combine_instruction_group {
+    my($group,@in_instrs) = @_;
+    my $gcode = '';             # Code for the entire group.
+    my $group_hotness = COLD;
 
-    # Pick up the macro to use and its flags (if any).
+    # Get code for the head of the group (if any).
+    my $head_name = "$group.head";
+    $c_code_used{$head_name} = 1;
+    my $head_code_ref = $c_code{$head_name};
+    if (defined $head_code_ref) {
+        my($head_code,$where,@c_args) = @{$head_code_ref};
+        @c_args and error("$where: no arguments allowed for " .
+                          "head function '$head_name()'");
+        $gcode = $head_code . "\n";
+    }
 
-    $macro = $macro{$name} if defined $macro{$name};
-    $flags = $macro_flags{$name} if defined $macro_flags{$name};
+    # Variables.
+    my %offsets;
+    my @instrs;
+    my %num_references;         # Number of references from other sub instructions.
+    my $group_size = 999;
 
     #
-    # Add any arguments to be included as macro arguments (for instance,
-    # 'p' is usually not an argument, except for calls).
+    # Calculate the number of references from other sub instructions.
+    # This number is useful in several ways:
+    #
+    # * If this number is 0, it is only used as the entry point for a
+    #   function, implying that it does not need a label and that operands
+    #   can be packed into the instruction word.
+    #
+    # * We'll use this number in the sort key, as a tie breaker for sub instructions
+    #   at the same instruction offset.
     #
+    foreach my $ref_instr (@in_instrs) {
+        my(undef,undef,$first_sub,@other_subs) = @$ref_instr;
+        $num_references{$first_sub} += 0; # Make sure it is defined.
+        foreach my $sub (@other_subs) {
+            $num_references{$sub}++;
+        }
+    }
 
-    while ($flags =~ /-arg_(\w)/g) {
-	$incl_arg{$1} = 1;
-    };
+    # Do basic error checking. Associate operands of instructions
+    # with the correct micro instructions. Calculate offsets for micro
+    # instructions.
+    foreach my $ref_instr (@in_instrs) {
+        my($specific,$arity,@subs) = @$ref_instr;
+        my $specific_key = "$specific/$arity";
+        my $specific_op_ref = $specific_op{$specific_key};
+        error("no $specific_key instruction")
+            unless defined $specific_op_ref;
+        foreach my $specific_op (@$specific_op_ref) {
+            my($name, $hotness, @args) = @{$specific_op};
+            $group_hotness = $hotness unless $group_hotness >= $hotness;
+            my $offset = 0;
+            my @rest = @args;
+            my @new_subs;
+            my $print_name = print_name($specific, @args);
+            my $opcase = $print_name;
+            my $last = $subs[$#subs];
+            foreach my $s (@subs) {
+                my $code = $c_code{$s};
+                my(undef,undef,@c_args) = @{$code};
+                my @first;
+                foreach (0..$#c_args) {
+                    push @first, shift @rest;
+                }
+                my $size = cg_combined_size(name => $s,
+                                            first => $num_references{$s} == 0,
+                                            args => \@first);
+                $offsets{$s} = $offset
+                    unless defined $offsets{$s} and $offsets{$s} < $offset;
+                $offset += $size - 1;
+                my $label = micro_label($s);
+                push @new_subs, [$opcase,$label,$s,$size-1,@first];
+                $opcase = '';
+            }
+            $spec_op_info{$print_name}->{'size'} = $offset + 1;
+            $group_size = $offset if $group_size >= $offset;
+            push @instrs, [$specific_key,@new_subs];
+        }
+    }
+
+    # Link the sub instructions for each instructions to each
+    # other.
+    my @all_instrs;
+    foreach my $instr (@instrs) {
+        my($specific_key,@subs) = @{$instr};
+        for (my $i = 0; $i < @subs; $i++) {
+            my($opcase,$label,$s,$size,@args) = @{$subs[$i]};
+            my $next = '';
+            (undef,$next) = @{$subs[$i+1]} if $i < $#subs;
+            my $instr_info = "$opcase:$label:$next:$s:$size:@args";
+            push @all_instrs, [$label,$s,$offsets{$s},$instr_info];
+        }
+    }
+
+    my %order_to_instrs;
+    my %label_to_offset;
+    my %order_to_offset;
+    foreach my $instr (@all_instrs) {
+        my($label,$s,$offset,$instr_info) = @$instr;
+        my $sort_key = sprintf("%02d.%02d", $offset, $num_references{$s});
+        push @{$order_to_instrs{$sort_key}}, $instr_info;
+        $label_to_offset{$label} = $offset;
+        $order_to_offset{$sort_key} = $offset;
+    }
+
+    my(@slots) = sort {$a <=> $b} keys %order_to_instrs;
+
+    # Now generate the code for the entire group.
+    my $offset = 0;
+    my @opcase_labels;
+    my %down;
+    my %up;
+    for(my $i = 0; $i < @slots; $i++) {
+        my $key = $slots[$i];
+
+        # Sort micro-instructions with OpCase before other micro-instructions.
+        my(@instrs) = @{$order_to_instrs{$key}};
+        my $order_func = sub {
+            my $a_key = ($a =~ /^:/) ? "1$a" : "0$a";
+            my $b_key = ($b =~ /^:/) ? "1$b" : "0$b";
+            $a_key cmp $b_key;
+        };
+        @instrs = sort $order_func @instrs;
+
+        my %seen;
+        foreach my $instr (@instrs) {
+            my($opcase,$label,$next,$s,$size,$args) = split ":", $instr;
+            my(@first) = split " ", $args;
+
+            my $seen_key = "$label:$next:" . scalar(@first);
+            next if $opcase eq '' and $seen{$seen_key};
+            $seen{$seen_key} = 1;
+            $seen_key .= $opcase;
+
+            if ($opcase ne '') {
+                $gcode .= "OpCase($opcase):\n";
+                push @opcase_labels, $opcase;
+            }
+            if ($num_references{$s}) {
+                $gcode .= "$label:\n";
+            }
+
+            my $flags = '';
+            my $transfer_to_next = '';
+            my $inc = 0;
+
+            unless ($i == $#slots) {
+                $flags = "-no_next";
+                my $next_offset = $label_to_offset{$next};
+                $inc = ($offset + $size) - $next_offset;
+                $transfer_to_next = "I += $inc;\n" if $inc;
+                $transfer_to_next .= "goto $next;\n\n";
+            }
+
+            my($gen_code,$down,$up) =
+                cg_combined_code(name => $s,
+                                 first => $num_references{$s} == 0,
+                                 extra_comments => $flags,
+                                 offset => $offset,
+                                 comp_size => $group_size-$offset,
+                                 inc => $inc,
+                                 args =>\@first);
+            my $spec_label = "$opcase$label";
+            $down{$spec_label} = $down;
+            $up{$spec_label} = $up;
+            $gcode .= $gen_code . $transfer_to_next;
+        }
+        $offset = $order_to_offset{$slots[$i+1]} if $i < $#slots;
+    }
+
+    foreach my $print_name (@opcase_labels) {
+        my $info = $spec_op_info{$print_name};
+        $info->{'adj'} = $info->{'size'} - $group_size - 1;
+    }
 
     #
-    # Pack arguments if requested.
+    # Assemble pack specifications for all instructions in the group.
     #
+    foreach my $instr (@instrs) {
+        my(undef,@subs) = @{$instr};
+        my $down = '';
+        my $up = '';
+        for (my $i = 0; $i < @subs; $i++) {
+            my($opcase,$label) = @{$subs[$i]};
+            my $spec_label = "$opcase$label";
+            if (defined $down{$spec_label}) {
+                $down = $down{$spec_label} . $down;
+                $up = $up . $up{$spec_label};
+            }
+        }
+        my $print_name = $subs[0]->[0];
+        my $info = $spec_op_info{$print_name};
+        $info->{'pack_spec'} = build_pack_spec("$down:$up");
+    }
+
+    ($group_hotness,"{\n$gcode\n}\n\n",@opcase_labels);
+}
+
+sub micro_label {
+    my $label = shift;
+    $label =~ s/[.]/__/g;
+    $label;
+}
 
-    if ($flags =~ /-pack/ && $hot) {
-        ($prefix, $pack_spec, @args) = do_pack(@args);
+
+#
+# Basic code generation for one instruction.
+#
+
+sub cg_basic {
+    my %params = (@_, pack_options => \@extended_pack_options);
+    my($size,$code,$pack_spec) = code_gen(%params);
+    $pack_spec = build_pack_spec($pack_spec);
+    ($size,$code,$pack_spec);
+}
+
+#
+# Calculate size for a micro instruction.
+#
+
+sub cg_combined_size {
+    my %params = (@_,
+                  pack_options => \@basic_pack_options,
+                  size_only => 1);
+    $params{pack_options} = \@extended_pack_options
+        if $params{first};
+    my($size) = code_gen(%params);
+    $size;
+}
+
+#
+# Generate code for a micro instruction.
+#
+
+sub cg_combined_code {
+    my %params = (@_, pack_options => \@basic_pack_options);
+    $params{pack_options} = \@extended_pack_options
+        if $params{first};
+    my($size,$code,$pack_spec) = code_gen(%params);
+    if ($pack_spec eq '') {
+        ($code,'','');
+    } else {
+        my($down,$up) = split /:/, $pack_spec;
+        ($code,$down,$up);
+    }
+}
+
+sub code_gen {
+    my %params = (extra_comments => '',
+                  offset => 0,
+                  inc => 0,
+                  size_only => 0,
+                  @_);
+    my $name = $params{name};
+    my $extra_comments = $params{extra_comments};
+    my $offset = $params{offset};
+    my $inc = $params{inc};
+    my @args = @{$params{args}};
+
+    my $size = 0;
+    my $flags = '';
+    my @f;
+    my $prefix = '';
+    my $tmp_arg_num = 1;
+    my $pack_spec = '';
+    my $var_decls = '';
+
+    #
+    # Pack arguments for hot code with an implementation.
+    #
+
+    my $c_code_ref = $c_code{$name};
+    if (defined $c_code_ref and $name ne 'catch') {
+        my $pack_options = $params{pack_options};
+        ($var_decls, $pack_spec, @args) = do_pack($name, $offset, $pack_options, @args);
     }
 
     #
@@ -993,259 +1450,696 @@ sub basic_generator {
     # the macro.
     #
 
+    my $need_block = 0;
+    my $arg_offset = $offset;
+    my $has_gen_dest = 0;
+    @args = map { s/[?]$//g; $_ } @args;
     foreach (@args) {
 	my($this_size) = $arg_size{$_};
       SWITCH:
 	{
-	    /^pack:(\d):(.*)/ and do { push(@f, $2);
-				       push(@f_types, 'packed');
-				       $this_size = $1;
-				       last SWITCH;
-				   };
-	    /r/    and do { push(@f, "r(0)"); push(@f_types, $_); last SWITCH };
-	    /[xy]/ and do { push(@f, "$_" . "b(Arg($size))");
-			     push(@f_types, $_);
-			     last SWITCH;
-			};
-	    /n/    and do { push(@f, "NIL"); push(@f_types, $_); last SWITCH };
-	    /s/    and do { my($tmp) = "targ$tmp_arg_num";
-			    $var_decls .= "Eterm $tmp; ";
-			    $tmp_arg_num++;
-			    push(@f, $tmp);
-			    push(@f_types, $_);
-			    $prefix .= "GetR($size, $tmp);\n";
-			    last SWITCH; };
-	    /d/    and do { $var_decls .= "Eterm dst; Eterm* dst_ptr; ";
-			    push(@f, "*dst_ptr");
-			    push(@f_types, $_);
-			    $prefix .= "dst = Arg($size);\n";
-			    $prefix .= "dst_ptr = REG_TARGET_PTR(dst);\n";
-			    last SWITCH;
-			};
-	    defined($incl_arg{$_})
-		and do { push(@f, "Arg($size)");
-			 push(@f_types, $_);
-			 last SWITCH;
-		     };
-
-	    /[fp]/ and do { $fail_type = $_; last SWITCH };
-
-	    /[eLIFEbASjPowlq]/ and do { last SWITCH; };
+	    /^packed:d:(\d):(.*)/ and do {
+                $var_decls .= "Eterm dst = $2;\n" .
+                    "Eterm* dst_ptr = REG_TARGET_PTR(dst);\n";
+                push(@f, "*dst_ptr");
+                $this_size = $1;
+                $has_gen_dest = 1;
+                last SWITCH;
+            };
+	    /^packed:[a-zA-z]:(\d):(.*)/ and do {
+                push(@f, $2);
+                $this_size = $1;
+                last SWITCH;
+            };
+	    /r/ and do {
+                push(@f, "r(0)");
+                last SWITCH;
+            };
+	    /[lxyS]/ and do {
+                push(@f, $_ . "b(" . arg_offset($arg_offset) . ")");
+                last SWITCH;
+            };
+	    /n/ and do {
+                push(@f, "NIL");
+                last SWITCH;
+            };
+	    /s/ and do {
+                my($tmp) = "targ$tmp_arg_num";
+                $var_decls .= "Eterm $tmp;\n";
+                $tmp_arg_num++;
+                push(@f, $tmp);
+                $prefix .= "GetR($arg_offset, $tmp);\n";
+                $need_block = 1;
+                last SWITCH;
+            };
+	    /d/ and do {
+                $var_decls .= "Eterm dst = " . arg_offset($arg_offset) . ";\n" .
+                    "Eterm* dst_ptr = REG_TARGET_PTR(dst);\n";
+                push(@f, "*dst_ptr");
+                $has_gen_dest = 1;
+                last SWITCH;
+            };
+            defined $arg_size{$_} and do {
+                push @f, arg_offset($arg_offset);
+                last SWITCH;
+            };
 
 	    die "$name: The generator can't handle $_, at";
 	}
 	$size += $this_size;
+        $arg_offset += $this_size;
     }
 
     #
-    # Add a fail action macro if requested.
+    # If the implementation is in beam_emu.c or if
+    # the caller only wants the size, we are done.
     #
+    if (not defined $c_code_ref or $params{size_only}) {
+        return ($size+1, undef, '');
+    }
 
-    $flags =~ /-fail_action/ and do {
-	$no_prefetch = 1;
-	if (!defined $fail_type) {
-	    my($i);
-	    for ($i = 0; $i < @f_types; $i++) {
-		local($_) = $f_types[$i];
-		/[rxycians]/ and do { push(@f, "Badmatch($f[$i])"); next };
-	    }
-	} elsif ($fail_type eq 'f') {
-	    push(@f, "ClauseFail()");
-	} else {
-	    my($i);
-	    for ($i = 0; $i < @f_types; $i++) {
-		local($_) = $f_types[$i];
-		/[rxycians]/ and do { push(@f, "Badmatch($f[$i])"); next };
-	    }
-	}
-    };
+    my $group_size = ($params{comp_size} || $size) + $inc;
 
     #
-    # Add a size argument if requested.
+    # Generate main body of the implementation.
     #
+    my($c_code,$where,@c_args) = @{$c_code_ref};
+    my %bindings;
+    $c_code_used{$name} = 1;
 
-    $flags =~ /-size/ and do {
-	push(@f, $size);
-    };
+    if (@f != @c_args) {
+        error("$where: defining '$name' with ", scalar(@c_args),
+              " arguments instead of expected ", scalar(@f), " arguments");
+    }
 
-    # Generate the macro if requested.
-    my($code);
-    if (defined $macro{$name}) {
-	my($macro_code) = "$prefix$macro(" . join(', ', @f) . ");";
-	$var_decls .= "BeamInstr tmp_packed1;"
-	    if $macro_code =~ /tmp_packed1/;
-	$var_decls .= "BeamInstr tmp_packed2;"
-	    if $macro_code =~ /tmp_packed2/;
-	if ($flags =~ /-nonext/) {
-	    $code = join("\n",
-			 "{ $var_decls",
-			 $macro_code,
-			 "}");
-	} elsif ($flags =~ /-goto:(\S*)/) {
-	    my $goto = $1;
-	    $code = join("\n",
-			 "{ $var_decls",
-			 $macro_code,
-			 "I += $size + 1;",
-			 "goto $goto;",
-			 "}");
-	} elsif ($no_prefetch) {
-	    $code = join("\n",
-			 "{ $var_decls",
-			 $macro_code,
-			 "Next($size);",
-			 "}", "");
-	} else {
-	    $code = join("\n",
-			 "{ $var_decls",
-			 "BeamInstr* next;",
-			 "PreFetch($size, next);",
-			 "$macro_code",
-			 "NextPF($size, next);",
-			 "}", "");
-	}
+    for (my $i = 0; $i < @f; $i++) {
+        my $var = $c_args[$i];
+        $bindings{$var} = $f[$i];
+    }
+    $bindings{'NEXT_INSTRUCTION'} = "I+" . ($group_size+$offset+1);
+    $bindings{'IP_ADJUSTMENT'} = $inc;
+    $c_code = eval { expand_all($c_code, \%bindings) };
+    unless (defined $c_code) {
+        warn $@;
+        error("... from the body of $name at $where");
+    }
+    my(@comments) = $c_code =~ m@//[|]\s*(.*)@g;
+    $c_code =~ s@//[|]\s*(.*)\n?@@g;
+    $flags = "@comments $extra_comments";
+
+    #
+    # Generate code for transferring to the next instruction.
+    #
+    my $dispatch_next;
+    my $instr_offset = $group_size + $offset + 1;
+
+    if ($flags =~ /-no_next/) {
+        $dispatch_next = "";
+    } elsif ($flags =~ /-no_prefetch/) {
+        $dispatch_next = "\nI += $instr_offset;\n" .
+            "ASSERT(VALID_INSTR(*I));\n" .
+            "Goto(*I);";
+    } else {
+        $var_decls .= "BeamInstr next_pf = BeamCodeAddr(I[$instr_offset]);\n";
+        $dispatch_next = "\nI += $instr_offset;\n" .
+            "ASSERT(VALID_INSTR(next_pf));\n" .
+            "GotoPF(next_pf);";
+    }
+
+    #
+    # Assemble the complete code for the instruction.
+    #
+    my $body = "$c_code$dispatch_next";
+    if ($need_block) {
+        $body = "$prefix\{\n$body\n}";
+    } else {
+        $body = "$prefix$body";
+    }
+    my $code = join("\n",
+                    "{",
+                    "$var_decls$body",
+                    "}", "");
+
+    # Make sure that $REFRESH_GEN_DEST() is used when a
+    # general destination ('d') may have been clobbered by
+    # a GC.
+    my $gc_error = verify_gc_code($code, $has_gen_dest);
+    if (defined $gc_error) {
+        warn $gc_error;
+        error("... from the body of $name at $where");
+    }
+
+    # Done.
+    ($size+1, $code, $pack_spec);
+}
+
+sub verify_gc_code {
+    my $code = shift;
+    my $has_gen_dest = shift;
+
+    return unless $has_gen_dest;
+
+    if ($code =~ /$GC_REGEXP/o) {
+        my $code_after_gc = substr($code, $+[0]);
+        unless ($code_after_gc =~ /dst_ptr = REG_TARGET_PTR/) {
+            return "pointer to destination register is invalid after GC -- " .
+                "use \$REFRESH_GEN_DEST()\n";
+        }
+    }
+    return undef;
+}
+
+sub arg_offset {
+    my $offset = shift;
+    "I[" . ($offset+1) . "]";
+}
+
+sub expand_all {
+    my($code,$bindings_ref) = @_;
+    my %bindings = %{$bindings_ref};
+
+    # Expand all $Var occurrences.
+    $code =~ s/[\$](\w[\w\d]*)(?!\()/defined $bindings{$1} ? $bindings{$1} : "\$$1"/ge;
+
+    # Find calls to macros, $name(...), and expand them.
+    my $res = "";
+    while ($code =~ /[\$](\w[\w\d]*)\(/) {
+        my $macro_name = $1;
+        my $keep = substr($code, 0, $-[0]);
+        my $after = substr($code, $+[0]);
+
+        my $body;
+        ($body,$code) = expand_macro($macro_name, $after, \%bindings);
+        $res .= "$keep$body";
+    }
+
+    $res . $code;
+}
+
+sub expand_macro {
+    my($name,$rest,$bindings_ref) = @_;
+
+    my $c_code = $c_code{$name};
+    defined $c_code or
+        error("calling undefined macro '$name'...");
+    $c_code_used{$name} = 1;
+    my ($body,$where,@vars) = @{$c_code};
+
+    # Separate the arguments into @args;
+    my @args;
+    my $level = 1;
+    my %inc = ('(' => 1, ')' => -1,
+               '[' => 1, ']' => -1,
+               '{' => 1, '}' => -1);
+    my $arg = undef;
+    while ($rest =~ /([,\(\[\{\}\]\)]|([^,\(\[\{\}\]\)]*))/g) {
+        my $token = $1;
+        my $inc = $inc{$token} || 0;
+        $level += $inc;
+        if ($level == 0) {
+            $rest = substr($rest, pos($rest));
+            push @args, $arg if defined $arg;
+            last;
+        }
+        if ($token eq ',') {
+            if ($level == 1) {
+                push @args, $arg;
+                $arg = "";
+            }
+            next;
+        }
+        $arg .= $token;
+    }
+
+    # Trim leading whitespace from each argument.
+    foreach my $arg (@args) {
+        $arg =~ s/^\s*//;
+    }
+
+    # Make sure that the number of arguments are correct.
+    if (@vars != @args) {
+        error("calling $name with ", scalar(@args),
+              " arguments instead of expected ", scalar(@vars), " arguments...");
+    }
+
+    # Now combine bindings from the parameter names and arguments.
+    my %bindings = %{$bindings_ref};
+    my %new_bindings;
+
+    # Keep the special, pre-defined bindings.
+    foreach my $key (qw(NEXT_INSTRUCTION IP_ADJUSTMENT)) {
+        $new_bindings{$key} = $bindings{$key};
+    }
+
+    for (my $i = 0; $i < @vars; $i++) {
+        my $arg = $args[$i];
+        $arg = eval { expand_all($arg, \%bindings) };
+        unless (defined $arg) {
+            warn $@;
+            die "... from the body of $name at $where\n";
+        }
+        $new_bindings{$vars[$i]} = $arg;
+    }
+
+    $body = eval { expand_all($body, \%new_bindings) };
+    unless (defined $body) {
+        warn $@;
+        die "... from the body of $name at $where\n";
+    }
+
+    # Handle built-in macros.
+    if ($name eq 'OPERAND_POSITION') {
+        if ($body =~ /^I\[(\d+)\]$/) {
+            $body = $1;
+        } else {
+            $body = 0;
+        }
+    } elsif ($name eq 'IF') {
+        my $expr = $new_bindings{Expr};
+        my $bool = eval $expr;
+        if ($@ ne '') {
+            &error("bad expression '$expr' in \$IF()");
+        }
+        my $part = $bool ? 'IfTrue' : 'IfFalse';
+        $body = $new_bindings{$part};
+    } elsif ($name eq 'REFRESH_GEN_DEST') {
+        $body = "dst_ptr = REG_TARGET_PTR(dst)";
     }
 
-    # Return the size and code for the macro (if any).
-    $size++;
-    ($size, $code, $pack_spec);
+
+    # Wrap body if needed and return result.
+    $body = "do {\n$body\n} while (0)"
+        if needs_do_wrapper($body);
+    ($body,$rest);
+}
+
+# Conservative heuristic to determine whether a do { ... } while(0)
+# wrapper is needed.
+sub needs_do_wrapper {
+    local $_ = shift;
+
+    s@^//[|][^\n]*\n@@;
+    s@^\s*@@s;
+    s@^/[*].*[*]/\s*@@s;
+    return 1 if /^(Eterm|Uint|Sint|int|unsigned)/; # Definitely needed.
+    return 0 if /^do/;
+    return 0 if /^SET_I/;
+    return 0 if /^SET_CP/;
+    return 0 if /^ERTS_NO_FPE_CHECK_INIT/;
+    return 0 if /^ASSERT/;
+    return 0 if /^DTRACE/;
+    return 0 if /^[A-Za-z_]*\s*=/;
+    return 0 if /^c_p->/;
+    return 0 if /^[A-Z_]*SWAPOUT/;
+    return 0 if /^if\s*[(]/;
+    return 0 if /^goto\b/;
+    return 0 if /^\d+/;
+    return 1;                   # Not sure, say that it is needed.
 }
 
 sub do_pack {
-    my(@args) = @_;
+    my($name,$offset,$pack_opts_ref,@args) = @_;
+    my @pack_opts = @$pack_opts_ref;
+    my $opt_arg_pos = -1;
+
+    # Look for an optional use operand not as the first argument.
+    if (@args and $args[0] !~ /[?]$/) {
+        for (my $pos = 0; $pos < @args; $pos++) {
+            if ($args[$pos] =~ /[?]$/) {
+                $opt_arg_pos = $pos;
+                last;
+            }
+        }
+    }
+
+    @args = map { s/[?]$//; $_ } @args; # Remove any optional use marker.
+
+    # If there is an optional operand, extend the array of pack options.
+    if ($opt_arg_pos >= 0) {
+        my @new_pack_opts = grep { $_ & PACK_IN_INSTR_WORD } @pack_opts;
+        @new_pack_opts = map {
+            ($_ & ~ PACK_IN_INSTR_WORD) | PACK_OPT_IN_INSTR_WORD;
+        } @new_pack_opts;
+        push @pack_opts, @new_pack_opts;
+    }
+
+    my $ret = ['', ':', @args];
+    my $score = 0;
+
+    foreach my $options (@pack_opts) {
+        my $this_opt_arg_pos = ($options & PACK_OPT_IN_INSTR_WORD) ? $opt_arg_pos : -1;
+        my($this_score,$this_result) =
+            do_pack_one($name, $options, $this_opt_arg_pos, $offset, @args);
+        if ($this_score > $score) {
+            $ret = $this_result;
+            $score = $this_score;
+        }
+    }
+    return @$ret;
+}
+
+sub do_pack_one {
+    my($name,$options,$opt_arg_pos,$offset,@args) = @_;
     my($packable_args) = 0;
-    my @is_packable;		# Packability (boolean) for each argument.
-    my $wide_packing = 0;
-    my(@orig_args) = @args;
+    my @bits_needed;            # Bits needed for each argument.
+    my $pack_in_iw = $options & PACK_IN_INSTR_WORD;
+
+    #
+    # Define the minimum number of bits needed for the packable argument types.
+    #
+    my %bits_needed = ('x' => 10,
+                       'y' => 10,
+                       'Q' => 10,
+                       'l' => 10,
+                       'S' => 16,
+                       'd' => 16,
+                       't' => 16);
+    if ($wordsize == 64) {
+        $bits_needed{'I'} = 32;
+        if ($options & PACK_JUMP) {
+            $bits_needed{'f'} = 32;
+            $bits_needed{'j'} = 32;
+        }
+    }
 
     #
-    # Count the number of packable arguments.  If we encounter any 's' or 'd'
-    # arguments, packing is not possible.
+    # Count the number of packable arguments.
     #
-    my $packable_types = "xytQ";
     foreach my $arg (@args) {
-	if ($arg =~ /^[$packable_types]/) {
+        if (defined $bits_needed{$arg}) {
 	    $packable_args++;
-	    push @is_packable, 1;
-	} elsif ($arg =~ /^I/ and $wordsize == 64 and $packable_args < 2) {
-	    $wide_packing = 1;
-	    push @is_packable, 1;
-	    if (++$packable_args == 2) {
-		# We can only pack two arguments. Turn off packing
-		# for the rest of the arguments.
-		$packable_types = "\xFF";
-	    }
-	} elsif ($arg =~ /^[sd]/) {
-	    return ('', '', @args);
-	} elsif ($arg =~ /^[scq]/ and $packable_args > 0) {
-	    # When packing, this operand will be picked up from the
-	    # code array, put onto the packing stack, and later put
-	    # back into a different location in the code. The problem
-	    # is that if this operand is a literal, the original
-	    # location in the code would have been remembered in a
-	    # literal patch.  For packing to work, we would have to
-	    # adjust the position in the literal patch. For the
-	    # moment, adding additional instructions to the packing
-	    # engine to handle this does not seem worth it, so we will
-	    # just turn off packing.
-	    return ('', '', @args);
+            push @bits_needed, $bits_needed{$arg};
 	} else {
-	    push @is_packable, 0;
+	    push @bits_needed, 0;
 	}
+        if ($arg =~ /^[fj]$/) {
+            # Only pack the first occurrence of 'f' or 'j'.
+            delete $bits_needed{'f'};
+            delete $bits_needed{'j'};
+        }
     }
 
     #
-    # Get out of here if too few or too many arguments.
+    # Return if there is nothing to pack.
     #
-    return ('', '', @args) if $packable_args < 2;
+    if ($packable_args == 0) {
+        return (-1);
+    } elsif ($packable_args == 1 and $options == 0) {
+        return (-1);
+    }
 
-    my($size) = 0;
-    my($pack_prefix) = '';
-    my($down) = '';		# Pack commands (towards instruction
-				# beginning).
-    my($up) = '';		# Pack commands (storing back while
-				# moving forward).
+    #
+    # Determine how many arguments we should pack into each word.
+    #
+    my @args_per_word;
+    my @need_wide_mask;
+    my $bits;
+    my $this_wordsize;
+    my $word = -1;
+
+    my $next_word = sub {
+        $word++;
+        $args_per_word[$word] = 0;
+        $need_wide_mask[$word] = 0;
+        $bits = 0;
+        $this_wordsize = $wordsize;
+    };
 
-    my $args_per_word = $args_per_word[$packable_args];
-    my @shift;
-    my @mask;
-    my @instr;
+    $next_word->();
+    $this_wordsize = 32 if $pack_in_iw;
+    for (my $arg_num = 0; $arg_num < @args; $arg_num++) {
+            my $needed = $bits_needed[$arg_num];
 
-    if ($wide_packing) {
-	@shift = ('0', 'BEAM_WIDE_SHIFT');
-	@mask = ('BEAM_WIDE_MASK', $WHOLE_WORD);
-	@instr = ('w', 'i');
-    } else {
-	@shift = @{$pack_shift[$args_per_word]};
-	@mask = @{$pack_mask[$args_per_word]};
-	@instr = @{$pack_instr[$args_per_word]};
+            next unless $needed;
+            next if $arg_num == $opt_arg_pos;
+
+            if ($bits+$needed > $this_wordsize) { # Does not fit.
+                $next_word->();
+            }
+            if ($args_per_word[$word] == 4) { # Can't handle more than 4 args.
+                $next_word->();
+            }
+            if ($needed == 32 and $args_per_word[$word] > 1) {
+                # Must only pack two arguments in this word, and there
+                # are already at least two arguments here.
+                $next_word->();
+            }
+            $args_per_word[$word]++;
+            $bits += $needed;
+            if ($needed == 32) {
+                $need_wide_mask[$word]++;
+            }
+            if ($need_wide_mask[$word] and $bits > 32) {
+                # Can only pack two things in a word where one
+                # item is 32 bits. Force the next item into
+                # the next word.
+                $bits = $this_wordsize;
+            }
     }
 
     #
+    # Try to balance packing between words.
+    #
+    if (@args_per_word == 1 and $args_per_word[0] == 1 and $pack_in_iw) {
+        # Don't rebalance.
+    } elsif ($args_per_word[$#args_per_word] == 1) {
+        if ($args_per_word[$#args_per_word-1] < 3) {
+            pop @args_per_word;
+        } else {
+            $args_per_word[$#args_per_word-1]--;
+            $args_per_word[$#args_per_word]++;
+        }
+    } elsif (@args_per_word == 2 and
+             $args_per_word[0] == 4 and
+             $args_per_word[1] == 2) {
+        $args_per_word[0] = 3;
+        $args_per_word[1] = 3;
+    } elsif (@args_per_word == 2 and
+             $args_per_word[0] == 3 and
+             $args_per_word[1] == 1) {
+        $args_per_word[0] = 2;
+        $args_per_word[1] = 2;
+    }
+
+    my $size = 0;
+    my $pack_prefix = '';
+    my $down = '';		# Pack commands (towards instruction
+				# beginning).
+    my $up = '';		# Pack commands (storing back while
+				# moving forward).
+    my $arg_num = 0;            # Number of argument.
+
+    # Skip an unpackable argument. Also handle packing of
+    # an single operand into the instruction word.
+    my $skip_unpackable = sub {
+        my($arg) = @_;
+
+        if ($arg_num == $opt_arg_pos) {
+            my $pack = chr(ord('#') + $arg_num);
+            $down = PACK_CMD_WIDE . "$pack$down";
+            my $unpack = "BeamExtraData(I[0])";
+            $args[$arg_num] = "packed:$arg:0:${arg}b($unpack)";
+        } elsif ($arg_size{$arg}) {
+            # Save the argument on the pack engine's stack.
+            my $push = 'g';
+            if ($type_bit{$arg} & $type_bit{'q'}) {
+                # The operand may be a literal.
+                $push = 'q';
+            } elsif ($type_bit{$arg} & $type_bit{'f'}) {
+                # The operand may be a failure label.
+                $push = 'f';
+            }
+            $down = "$push${down}";
+            $up = "${up}p";
+        }
+    };
+
+    #
     # Now generate the packing instructions.  One complication is that
     # the packing engine works from right-to-left, but we must generate
     # the instructions from left-to-right because we must calculate
     # instruction sizes from left-to-right.
+    for (my $word = 0; $word < @args_per_word; $word++) {
+        my $ap = 0;              # Argument number within word.
+        my $packed_var = "tmp_packed" . ($word+1);
+        my $args_per_word = $args_per_word[$word];
+        my $pack_word_size = ($pack_in_iw && $word == 0) ? 32 : $wordsize;
+
+        my($shref,$mref,$iref,$unpack_suffix)  =
+            get_pack_parameters($name, $args_per_word, $pack_word_size,
+                                $need_wide_mask[$word]);
+        my @shift = @$shref;
+        my @mask = @$mref;
+        my @instr = @$iref;
+
+        while ($ap < $args_per_word) {
+            my $reg = $args[$arg_num];
+            my $this_size = $arg_size{$reg};
+
+            if ($bits_needed[$arg_num]) {
+                $this_size = 0;
+
+                if ($ap == 0) {
+                    my $packed_data;
+                    if ($pack_in_iw and $word == 0) {
+                        $packed_data = "BeamExtraData(I[0])";
+                        if ($args_per_word == 1) {
+                            $packed_var = $packed_data;
+                        } else {
+                            $pack_prefix .= "Eterm $packed_var = $packed_data;\n";
+                        }
+                        my $pack = chr(ord('#') + $size);
+                        $down = "$pack$down";
+                    } else {
+                        $packed_data = arg_offset($size + $offset);
+                        $pack_prefix .= "Eterm $packed_var = $packed_data;\n";
+                        $down = "P$down";
+                        $up .= "p";
+                        $this_size = 1;
+                    }
+                }
+
+                $down = "$instr[$ap]$down";
+                my $unpack = make_unpack($packed_var, $shift[$ap], $mask[$ap]);
+                my $macro = "$reg$unpack_suffix";
+                $args[$arg_num] = "packed:$reg:$this_size:$macro($unpack)";
+
+                $ap++;
+            } else {
+                $skip_unpackable->($reg);
+            }
+            $size += $this_size;
+            $arg_num++;
+        }
+    }
+
     #
-    # XXX Packing 3 't's in one word won't work.  Sorry.
-
-    my $did_some_packing = 0;	# Nothing packed yet.
-    my($ap) = 0;		# Argument number within word.
-    my($tmpnum) = 1;		# Number of temporary variable.
-    my($expr) = '';
-    for (my $i = 0; $i < @args; $i++) {
-	my($reg) = $args[$i];
-	my($this_size) = $arg_size{$reg};
-	if ($is_packable[$i]) {
-	    $this_size = 0;
-	    $did_some_packing = 1;
-
-	    if ($ap == 0) {
-		$pack_prefix .= "tmp_packed$tmpnum = Arg($size);\n";
-		$up .= "p";
-		$down = "P$down";
-		$this_size = 1;
-	    }
+    # Skip any unpackable arguments at the end.
+    #
+    while ($arg_num < @args) {
+        my $arg = $args[$arg_num];
+        $skip_unpackable->($arg);
+        $size += $arg_size{$arg};
+        $arg_num++;
+    }
 
-	    $down = "$instr[$ap]$down";
-	    my($unpack) = make_unpack($tmpnum, $shift[$ap], $mask[$ap]);
-	    $args[$i] = "pack:$this_size:$reg" . "b($unpack)";
+    my $pack_spec = "$down:$up";
+    my $score = pack_score($options, @args);
 
-	    if (++$ap == $args_per_word) {
-		$ap = 0;
-		$tmpnum++;
-	    }
-	} elsif ($arg_size{$reg} && $did_some_packing) {
-	    #
-	    # This is an argument that can't be packed.  Normally, we must
-	    # save it on the pack engine's stack, unless:
-	    #
-	    # 1. The argument has zero size (e.g. r(0)).  Such arguments
-	    #    will not be loaded.  They disappear.
-	    # 2. If the argument is on the left of the first packed argument,
-	    #    the packing engine will never access it (because the engine
-	    #    operates from right-to-left).
-	    #
+    return ($score, [$pack_prefix,$pack_spec,@args]);
+}
 
-	    $down = "g${down}";
-	    $up = "${up}p";
-	}
-	$size += $this_size;
+sub get_pack_parameters {
+    my($name,$args_per_word,$pack_word_size,$wide_mask) = @_;
+    my(@shift,@mask,@instr);
+    my $unpack_suffix = 'b';
+
+    if ($wide_mask and $args_per_word > 1) {
+        @shift = ('0', 'BEAM_WIDE_SHIFT');
+        @mask = ('BEAM_WIDE_MASK', $WHOLE_WORD);
+        @instr = (PACK_CMD_WIDE) x 2;
+    } elsif ($args_per_word == 1) {
+        @shift = ('0');
+        @mask = ($WHOLE_WORD);
+        @instr = (PACK_CMD_WIDE);
+    } elsif ($args_per_word == 2) {
+        if ($pack_word_size != $wordsize) {
+            # 64-bit word size, pack 32 bits into instruction word.
+            @shift = ('0', 'BEAM_TIGHT_SHIFT');
+            @mask  = ('BEAM_TIGHT_MASK', $WHOLE_WORD);
+            @instr = (PACK_CMD_TIGHT) x 2;
+        } else {
+            # 32/64 bit word size
+            @shift = ('0', 'BEAM_LOOSE_SHIFT');
+            @mask  = ('BEAM_LOOSE_MASK', $WHOLE_WORD);
+            @instr = (PACK_CMD_LOOSE) x 2;
+        }
+    } elsif ($args_per_word == 3) {
+        if ($pack_word_size != $wordsize) {
+            # 64-bit word size, pack 3 register numbers into instruction word.
+            @shift = ('0', 'BEAM_TIGHTEST_SHIFT', '(2*BEAM_TIGHTEST_SHIFT)');
+            @mask = ('BEAM_TIGHTEST_MASK', 'BEAM_TIGHTEST_MASK', $WHOLE_WORD);
+            @instr = (PACK_CMD_TIGHTEST) x 3;
+            $unpack_suffix = '';
+        } else {
+            # 32/64 bit word size.
+            @shift = ('0', 'BEAM_TIGHT_SHIFT', '(2*BEAM_TIGHT_SHIFT)');
+            if ($wordsize == 32) {
+                @mask = ('BEAM_TIGHT_MASK') x 3;
+            } elsif ($wordsize == 64) {
+                @mask = ('BEAM_TIGHT_MASK', 'BEAM_TIGHT_MASK', $WHOLE_WORD);
+            }
+            @instr = (PACK_CMD_TIGHT) x 3;
+        }
+    } elsif ($args_per_word == 4) {
+        # 64 bit word size only.
+        @shift = ('0',
+                  'BEAM_LOOSE_SHIFT',
+                  '(2*BEAM_LOOSE_SHIFT)',
+		  '(3*BEAM_LOOSE_SHIFT)');
+        @mask = ('BEAM_LOOSE_MASK', 'BEAM_LOOSE_MASK',
+                 'BEAM_LOOSE_MASK', $WHOLE_WORD);
+        @instr = (PACK_CMD_LOOSE) x 4;
     }
 
-    my $pack_spec = $down . $up;
-    return ($pack_prefix, $pack_spec, @args);
+    unless (@shift) {
+        error("$name: internal packing error: args_per_word=$args_per_word, " .
+              "pack_word_size=$pack_word_size");
+    }
+
+    (\@shift,\@mask,\@instr,$unpack_suffix);
+}
+
+sub pack_score {
+    my($options,@args) = @_;
+    my $size = 0;
+
+    # Calculate the number of words.
+    foreach (@args) {
+        if (/^packed:[^:]*:(\d+)/) {
+            $size += $1;
+        } else {
+            $size += $arg_size{$_}
+        }
+    }
+
+    # Less numbers of words give a higher score; for the same number of
+    # words, using PACK_JUMP or PACK_IN_INSTR_WORD gives a lower score.
+    my $score = 1 + 10*($max_spec_operands - $size);
+    if (($options & PACK_OPT_IN_INSTR_WORD) != 0) {
+        $score += 4;
+    } elsif ($options == PACK_IN_INSTR_WORD) {
+        $score += 0;
+    } elsif ($options == PACK_JUMP) {
+        $score += 1;
+    } elsif ($options == (PACK_JUMP|PACK_IN_INSTR_WORD)) {
+        $score += 2;
+    } elsif ($options == 0) {
+        $score += 3;
+    }
+    $score;
 }
 
 sub make_unpack {
-    my($tmpnum, $shift, $mask) = @_;
+    my($packed_var, $shift, $mask) = @_;
 
-    my($e) = "tmp_packed$tmpnum";
+    my $e = $packed_var;
     $e = "($e>>$shift)" if $shift;
     $e .= "&$mask" unless $mask eq $WHOLE_WORD;
     $e;
 }
 
+sub build_pack_spec {
+    my $pack_spec = shift;
+    return '' if $pack_spec eq '';
+    my($down,$up) = split /:/, $pack_spec;
+    while ($down =~ /[gfq]$/ and $up =~ /^p/) {
+        $down = substr($down, 0, -1);
+        $up = substr($up, 1);
+    }
+    "$down$up";
+}
+
 sub quote {
     local($_) = @_;
     return "'$_'" if $_ eq 'try';
@@ -1286,8 +2180,11 @@ sub parse_transformation {
     #
 
     my @to;
-    if ($to =~ /^(\w+)\((.*?)\)/) {
-	my($name, $arglist) = ($1, $2);
+    if ($to =~ /^(\w+)\((.*?)\)(.*)/) {
+	my($name, $arglist, $garbage) = ($1, $2, $3);
+        if ($garbage =~ /\S/) {
+            error("garbage after call to '$name()'");
+        }
 	@to = (compile_transform_function($name, split(/\s*,\s*/, $arglist)));
     } else {
 	@to = split(/\s*\|\s*/, $to);
@@ -1357,12 +2254,19 @@ sub tr_parse_op {
     if (/^([a-z*]+)(.*)/) {
 	$type = $1;
 	$_ = $2;
+        error("$type: only a single type is allowed on right side of transformations")
+            if not $src and length($type) > 1;
 	foreach (split('', $type)) {
-	    error("bad type in $op")
-		unless defined $type_bit{$_} or $type eq '*';
-	    $_ eq 'r' and
-		error("$op: 'r' is not allowed in transformations")
-	}
+            next if $src and $type eq '*';
+            error("$op: not a type")
+                unless defined $type_bit{$_};
+            error("$op: the type '$_' is not allowed in transformations")
+                unless defined $pattern_type{$_};
+            if (not $src) {
+                error("$op: type '$_' is not allowed on the right side of transformations")
+                    unless defined $construction_type{$_};
+            }
+        }
     }
 
     # Get an optional condition. (In source.)
@@ -1395,10 +2299,18 @@ sub tr_parse_op {
     }
 
     # Get an optional value. (In destination.)
-    $type_val = $type eq 'x' ? 1023 : 0;
+    if ($type eq 'x') {
+        $type_val = 1023;
+    } elsif ($type eq 'a') {
+        $type_val = 'am_Empty';
+    } else {
+        $type_val = 0;
+    }
     if (/^=(.*)/) {
-	error("value not allowed in source: $op")
+	error("$op: value not allowed in source")
 	    if $src;
+        error("$op: the type 'n' must not be given a value")
+            if $type eq 'n';
 	$type_val = $1;
 	$_ = '';
     }
@@ -1408,13 +2320,16 @@ sub tr_parse_op {
     error("garbage '$_' after operand: $op")
 	unless /^\s*$/;
 
-    # Test that destination has no conditions.
+    # Check the conditions.
 
-    unless ($src) {
-	error("condition not allowed in destination: $op")
+    if ($src) {
+        error("$op: the type '$type' is not allowed to be compared with a literal value")
+            if $cond and not $construction_type{$type};
+    } else {
+	error("$op: condition not allowed in destination")
 	    if $cond;
-	error("variable name and type cannot be combined in destination: $op")
-	    if $var && $type;
+	error("$op: variable name and type cannot be combined in destination")
+	    if $var and $type;
     }
 
     ($var,$type,$type_val,$cond,$cond_val);
diff --git a/erts/emulator/utils/make_tables b/erts/emulator/utils/make_tables
index 47e1528958..094a35ae4b 100755
--- a/erts/emulator/utils/make_tables
+++ b/erts/emulator/utils/make_tables
@@ -59,7 +59,6 @@ my %dirty_bif_tab;
 
 my @bif;
 my @bif_info;
-my $dirty_schedulers = 'no';
 my $dirty_schedulers_test = 'no';
 my $hipe = 'no';
 
@@ -73,10 +72,6 @@ while (@ARGV && $ARGV[0] =~ /^-(\w+)/) {
 	$include = shift;
 	die "No directory for -include argument specified"
 	    unless defined $include;
-    } elsif($opt eq '-ds') {
-	$dirty_schedulers = shift;
-	die "No -ds argument specified"
-	    unless defined $dirty_schedulers;
     } elsif($opt eq '-dst') {
 	$dirty_schedulers_test = shift;
 	die "No -dst argument specified"
@@ -140,21 +135,19 @@ while (<>) {
 	push(@bif_info, [$type, $sched_type, $alias3, $alias]);
     } elsif ($type eq 'dirty-cpu' or $type eq 'dirty-io'
 	     or $type eq 'dirty-cpu-test' or $type eq 'dirty-io-test') {
-	if ($dirty_schedulers eq 'yes') {
-	    my($bif,$other) = (@args);
-	    $bif =~ m@^([a-z_.'0-9]+):(.*)/(\d)$@ or error("invalid BIF");
-	    my($mod,$name,$arity) = ($1,$2,$3);
-	    my $mfa = "$mod:$name/$arity";
-	    if (($type eq 'dirty-cpu')
-		or (($dirty_schedulers_test eq 'yes')
-		    and ($type eq 'dirty-cpu-test'))) {
-		$dirty_bif_tab{$mfa} = 'dirty_cpu';
-	    } elsif (($type eq 'dirty-io')
-		or (($dirty_schedulers_test eq 'yes')
-		    and ($type eq 'dirty-io-test'))) {
-		$dirty_bif_tab{$mfa} = 'dirty_io';
-	    }
-	}
+        my($bif,$other) = (@args);
+        $bif =~ m@^([a-z_.'0-9]+):(.*)/(\d)$@ or error("invalid BIF");
+        my($mod,$name,$arity) = ($1,$2,$3);
+        my $mfa = "$mod:$name/$arity";
+        if (($type eq 'dirty-cpu')
+            or (($dirty_schedulers_test eq 'yes')
+                and ($type eq 'dirty-cpu-test'))) {
+            $dirty_bif_tab{$mfa} = 'dirty_cpu';
+        } elsif (($type eq 'dirty-io')
+                 or (($dirty_schedulers_test eq 'yes')
+                     and ($type eq 'dirty-io-test'))) {
+            $dirty_bif_tab{$mfa} = 'dirty_io';
+        }
     } else {
 	error("invalid line");
     }
diff --git a/erts/etc/common/Makefile.in b/erts/etc/common/Makefile.in
index 5b1b9119ce..1f35cef669 100644
--- a/erts/etc/common/Makefile.in
+++ b/erts/etc/common/Makefile.in
@@ -56,7 +56,7 @@ ERTS_INCL = -I$(ERL_TOP)/erts/include \
 
 CC        = @CC@
 WFLAGS    = @WFLAGS@
-CFLAGS    = @CFLAGS@ @DEFS@ $(TYPE_FLAGS) @WFLAGS@ -I$(SYSDIR) -I$(EMUDIR) \
+CFLAGS    = @CFLAGS@ @DEFS@ $(TYPE_FLAGS) @WFLAGS@ -I$(SYSOSDIR) -I$(EMUDIR) -I. \
             -I$(COMSYSDIR) $(ERTS_INCL) -DOTP_SYSTEM_VERSION=\"$(SYSTEM_VSN)\"
 LD        = @LD@
 LIBS      = @LIBS@
@@ -69,9 +69,9 @@ endif
 
 ifeq ($(TARGET),win32)
 ifeq ($(TYPE),debug)
-CFLAGS = $(subst -O2,-g,@CFLAGS@ @DEFS@ $(TYPE_FLAGS) @WFLAGS@ -I$(SYSDIR) \
-            -I$(EMUDIR) -I$(COMSYSDIR) $(ERTS_INCL) \
-            -DOTP_SYSTEM_VERSION=\"$(SYSTEM_VSN)\")
+CFLAGS = $(subst -O2,-g,@CFLAGS@ @DEFS@ $(TYPE_FLAGS) @WFLAGS@ -I$(SYSOSDIR) \
+	-I$(EMUDIR) -I$(COMSYSDIR) $(ERTS_INCL) \
+	-DOTP_SYSTEM_VERSION=\"$(SYSTEM_VSN)\")
 LDFLAGS += -g
 endif
 endif
@@ -81,7 +81,8 @@ OBJDIR    = $(ERL_TOP)/erts/obj$(TYPEMARKER)/$(TARGET)
 EMUDIR    = $(ERL_TOP)/erts/emulator/beam
 COMSYSDIR = $(ERL_TOP)/erts/emulator/sys/common
 EMUOSDIR  = $(ERL_TOP)/erts/emulator/@ERLANG_OSTYPE@
-SYSDIR    = $(ERL_TOP)/erts/emulator/sys/@ERLANG_OSTYPE@
+SYSDIR    = $(ERL_TOP)/erts/emulator/sys/common
+SYSOSDIR  = $(ERL_TOP)/erts/emulator/sys/@ERLANG_OSTYPE@
 DRVDIR    = $(ERL_TOP)/erts/emulator/drivers/@ERLANG_OSTYPE@
 UXETC     = ../unix
 WINETC	  = ../win32
diff --git a/erts/etc/common/ct_run.c b/erts/etc/common/ct_run.c
index 6639c83778..efa7ac3493 100644
--- a/erts/etc/common/ct_run.c
+++ b/erts/etc/common/ct_run.c
@@ -20,16 +20,7 @@
 /*
  * Purpose: Common Test front-end.
  */
-#ifdef HAVE_CONFIG_H
-#  include "config.h"
-#endif
-
-#include "sys.h"
-#ifdef __WIN32__
-#include <winbase.h>
-#endif
-
-#include <ctype.h>
+#include "etc_common.h"
 
 #define NO 0
 #define YES 1
diff --git a/erts/etc/common/dialyzer.c b/erts/etc/common/dialyzer.c
index c8d977f6de..b45d5c7ca7 100644
--- a/erts/etc/common/dialyzer.c
+++ b/erts/etc/common/dialyzer.c
@@ -20,16 +20,8 @@
 /*
  * Purpose: Dialyzer front-end.
  */
-#ifdef HAVE_CONFIG_H
-#  include "config.h"
-#endif
-
-#include "sys.h"
-#ifdef __WIN32__
-#include <winbase.h>
-#endif
 
-#include <ctype.h>
+#include "etc_common.h"
 
 #define NO 0
 #define YES 1
@@ -263,7 +255,7 @@ int main(int argc, char** argv)
     }
 
     PUSH("+B");
-    PUSH2("-boot", "start_clean");
+    PUSH2("-boot", "no_dot_erlang");
     PUSH3("-run", "dialyzer", "plain_cl");
     PUSH("-extra");
 
diff --git a/erts/etc/common/erlc.c b/erts/etc/common/erlc.c
index cbbd2a37cd..aa99c69100 100644
--- a/erts/etc/common/erlc.c
+++ b/erts/etc/common/erlc.c
@@ -20,19 +20,7 @@
 /*
  * Purpose: Common compiler front-end.
  */
-#ifdef HAVE_CONFIG_H
-#  include "config.h"
-#endif
-
-#include "sys.h"
-#ifdef __WIN32__
-#include <winbase.h>
-/* FIXE ME config_win32.h? */
-#define HAVE_STRERROR 1
-#define snprintf _snprintf
-#endif
-
-#include <ctype.h>
+#include "etc_common.h"
 
 #define NO 0
 #define YES 1
@@ -246,7 +234,7 @@ int main(int argc, char** argv)
     PUSH("+A0");
     PUSH("-noinput");
     PUSH2("-mode", "minimal");
-    PUSH2("-boot", "start_clean");
+    PUSH2("-boot", "no_dot_erlang");
     PUSH3("-s", "erl_compile", "compile_cmdline");
     PUSH("-extra");
 
diff --git a/erts/etc/common/erlexec.c b/erts/etc/common/erlexec.c
index eaa94cd5e4..f7c8c27d53 100644
--- a/erts/etc/common/erlexec.c
+++ b/erts/etc/common/erlexec.c
@@ -23,14 +23,9 @@
  * additions required for Windows NT.
  */
 
-#ifdef HAVE_CONFIG_H
-#  include "config.h"
-#endif
+#include "etc_common.h"
 
-#include "sys.h"
 #include "erl_driver.h"
-#include <stdlib.h>
-#include <stdarg.h>
 #include "erl_misc_utils.h"
 
 #ifdef __WIN32__
@@ -195,9 +190,7 @@ void error(char* format, ...);
  * Local functions.
  */
 
-#if !defined(ERTS_HAVE_SMP_EMU) || !defined(ERTS_HAVE_PLAIN_EMU)
 static void usage_notsup(const char *switchname, const char *alt);
-#endif
 static char **build_args_from_env(char *env_var);
 static char **build_args_from_string(char *env_var);
 static void initial_argv_massage(int *argc, char ***argv);
@@ -245,7 +238,7 @@ static int verbose = 0;		/* If non-zero, print some extra information. */
 static int start_detached = 0;	/* If non-zero, the emulator should be
 				 * started detached (in the background).
 				 */
-static int start_smp_emu = 0;   /* Start the smp emulator. */
+static int start_smp_emu = 1;   /* Start the smp emulator. */
 static const char* emu_type = 0; /* Type of emulator (lcnt, valgrind, etc) */
 
 #ifdef __WIN32__
@@ -468,10 +461,6 @@ int main(int argc, char **argv)
      * Construct the path of the executable.
      */
     cpuinfo = erts_cpu_info_create();
-    /* '-smp auto' is default */ 
-#ifdef ERTS_HAVE_SMP_EMU
-    start_smp_emu = 1;
-#endif
 
 #if defined(__WIN32__) && defined(WIN32_ALWAYS_DEBUG)
     emu_type = "debug";
@@ -503,23 +492,13 @@ int main(int argc, char **argv)
 		    i++;
 		smp_enable:
                     ;
-#if !defined(ERTS_HAVE_SMP_EMU)
-		    usage_notsup("-smp enable", "");
-#endif
 		} else if (strcmp(argv[i+1], "disable") == 0) {
 		    i++;
 		smp_disable:
-#ifdef ERTS_HAVE_PLAIN_EMU
-                    start_smp_emu = 0;
-#else
                     usage_notsup("-smp disable", " Use \"+S 1\" instead.");
-#endif
 		} else {
 		smp:
                     ;
-#if !defined(ERTS_HAVE_SMP_EMU)
-		    usage_notsup("-smp", "");
-#endif
 		}
 	    } else if (strcmp(argv[i], "-smpenable") == 0) {
 		goto smp_enable;
@@ -558,19 +537,44 @@ int main(int argc, char **argv)
     } else {
         add_Eargs(emu);       /* argv[0] = erl or cerl */
     }
-    /*
-     * Add the bindir to the path (unless it is there already).
-     */
+
+    /* Add the bindir to the front of the PATH, and remove all subsequent
+     * occurrences to avoid ballooning it on repeated up/downgrades. */
 
     s = get_env("PATH");
-    if (!s) {
-	erts_snprintf(tmpStr, sizeof(tmpStr), "%s" PATHSEP "%s" DIRSEP "bin", bindir, rootdir);
-    } else if (strstr(s, bindir) == NULL) {
-	erts_snprintf(tmpStr, sizeof(tmpStr), "%s" PATHSEP "%s" DIRSEP "bin" PATHSEP "%s", bindir,
-		rootdir, s);
+
+    if (s == NULL) {
+        erts_snprintf(tmpStr, sizeof(tmpStr),
+            "%s" PATHSEP "%s" DIRSEP "bin" PATHSEP, bindir, rootdir);
+    } else if (strstr(s, rootdir) == NULL) {
+        erts_snprintf(tmpStr, sizeof(tmpStr),
+            "%s" PATHSEP "%s" DIRSEP "bin" PATHSEP "%s", bindir, rootdir, s);
     } else {
-	erts_snprintf(tmpStr, sizeof(tmpStr), "%s", s);
+        const char *bindir_slug, *bindir_slug_index;
+        int bindir_slug_length;
+        const char *in_index;
+        char *out_index;
+
+        erts_snprintf(tmpStr, sizeof(tmpStr), "%s" PATHSEP, bindir);
+
+        bindir_slug = strsave(tmpStr);
+        bindir_slug_length = strlen(bindir_slug);
+
+        out_index = &tmpStr[bindir_slug_length];
+        in_index = s;
+
+        while ((bindir_slug_index = strstr(in_index, bindir_slug))) {
+            int block_length = (bindir_slug_index - in_index);
+
+            memcpy(out_index, in_index, block_length);
+
+            in_index = bindir_slug_index + bindir_slug_length;
+            out_index += block_length;
+        }
+
+        strcpy(out_index, in_index);
     }
+
     free_env_val(s);
     set_env("PATH", tmpStr);
     
@@ -832,6 +836,28 @@ int main(int argc, char **argv)
 		      add_Eargs(argv[i+1]);
 		      i++;
 		      break;
+		  case 'I':
+                      if (argv[i][2] == 'O' && (argv[i][3] == 't' || argv[i][3] == 'p')) {
+                          if (argv[i][4] != '\0')
+                              goto the_default;
+                          argv[i][0] = '-';
+                          add_Eargs(argv[i]);
+                          add_Eargs(argv[i+1]);
+                          i++;
+                          break;
+                      }
+                      if (argv[i][2] == 'O' && argv[i][3] == 'P' &&
+                          (argv[i][4] == 't' || argv[i][4] == 'p')) {
+                          if (argv[i][5] != '\0')
+                              goto the_default;
+                          argv[i][0] = '-';
+                          add_Eargs(argv[i]);
+                          add_Eargs(argv[i+1]);
+                          i++;
+                          break;
+                      }
+                      usage(argv[i]);
+                      break;
 		  case 'S':
 		      if (argv[i][2] == 'P') {
 			  if (argv[i][3] != '\0')
@@ -887,8 +913,8 @@ int main(int argc, char **argv)
 		  case 'c':
 		      argv[i][0] = '-';
 		      if (argv[i][2] == '\0' && i+1 < argc) {
-			  if (sys_strcmp(argv[i+1], "true") == 0
-			      || sys_strcmp(argv[i+1], "false") == 0) {
+			  if (strcmp(argv[i+1], "true") == 0
+			      || strcmp(argv[i+1], "false") == 0) {
 			      add_Eargs(argv[i]);
 			      add_Eargs(argv[i+1]);
 			      i++;
@@ -1160,15 +1186,6 @@ usage_aux(void)
 #ifdef __WIN32__
 	  "[-start_erl [datafile]] "
 #endif
-	  "[-smp [auto"
-#ifdef ERTS_HAVE_SMP_EMU
-	  "|enable"
-#endif
-#ifdef ERTS_HAVE_PLAIN_EMU
-	  "|disable"
-#endif
-	  "]"
-	  "] "
 	  "[-make] [-man [manopts] MANPAGE] [-x] [-emu_args] [-start_epmd BOOLEAN] "
 	  "[-args_file FILENAME] [+A THREADS] [+a SIZE] [+B[c|d|i]] [+c [BOOLEAN]] "
 	  "[+C MODE] [+h HEAP_SIZE_OPTION] [+K BOOLEAN] "
@@ -1189,14 +1206,12 @@ usage(const char *switchname)
     usage_aux();
 }
 
-#if !defined(ERTS_HAVE_SMP_EMU) || !defined(ERTS_HAVE_PLAIN_EMU)
 static void
 usage_notsup(const char *switchname, const char *alt)
 {
     fprintf(stderr, "Argument \'%s\' not supported.%s\n", switchname, alt);
     usage_aux();
 }
-#endif
 
 static void
 usage_format(char *format, ...)
@@ -2195,18 +2210,18 @@ static WCHAR *utf8_to_utf16(unsigned char *bytes)
     res = target = emalloc((num + 1) * sizeof(WCHAR));
     while (*bytes) {
 	if (((*bytes) & ((unsigned char) 0x80)) == 0) {
-	    unipoint = (Uint) *bytes;
+	    unipoint = (unsigned int) *bytes;
 	    ++bytes;
 	} else if (((*bytes) & ((unsigned char) 0xE0)) == 0xC0) {
 	    unipoint = 
-		(((Uint) ((*bytes) & ((unsigned char) 0x1F))) << 6) |
-		((Uint) (bytes[1] & ((unsigned char) 0x3F))); 	
+		(((unsigned int) ((*bytes) & ((unsigned char) 0x1F))) << 6) |
+		((unsigned int) (bytes[1] & ((unsigned char) 0x3F)));
 	    bytes += 2;
 	} else if (((*bytes) & ((unsigned char) 0xF0)) == 0xE0) {
 	    unipoint = 
-		(((Uint) ((*bytes) & ((unsigned char) 0xF))) << 12) |
-		(((Uint) (bytes[1] & ((unsigned char) 0x3F))) << 6) |
-		((Uint) (bytes[2] & ((unsigned char) 0x3F)));
+		(((unsigned int) ((*bytes) & ((unsigned char) 0xF))) << 12) |
+		(((unsigned int) (bytes[1] & ((unsigned char) 0x3F))) << 6) |
+		((unsigned int) (bytes[2] & ((unsigned char) 0x3F)));
 	    if (unipoint > 0xFFFF) {
 		 unipoint = (unsigned int) '?';
 	    }
@@ -2225,7 +2240,7 @@ static WCHAR *utf8_to_utf16(unsigned char *bytes)
 
 static int put_utf8(WCHAR ch, unsigned char *target, int sz, int *pos)
 {
-    Uint x = (Uint) ch;
+    unsigned int x = (unsigned int) ch;
     if (x < 0x80) {
     if (*pos >= sz) {
 	return -1;
diff --git a/erts/etc/common/escript.c b/erts/etc/common/escript.c
index 9cd5dd3fab..d739d21f12 100644
--- a/erts/etc/common/escript.c
+++ b/erts/etc/common/escript.c
@@ -20,16 +20,8 @@
 /*
  * Purpose: escript front-end.
  */
-#ifdef HAVE_CONFIG_H
-#  include "config.h"
-#endif
-
-#include "sys.h"
-#ifdef __WIN32__
-#include <winbase.h>
-#endif
 
-#include <ctype.h>
+#include "etc_common.h"
 
 static int debug = 0;		/* Bit flags for debug printouts. */
 
@@ -529,7 +521,7 @@ main(int argc, char** argv)
     free_env_val(env);
 
     PUSH("+B");
-    PUSH2("-boot", "start_clean");
+    PUSH2("-boot", "no_dot_erlang");
     PUSH("-noshell");
 
     /*
diff --git a/erts/etc/common/etc_common.h b/erts/etc/common/etc_common.h
new file mode 100644
index 0000000000..3f26064a9e
--- /dev/null
+++ b/erts/etc/common/etc_common.h
@@ -0,0 +1,65 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 2017. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+/*
+ * Purpose: common includes for all etc programs
+ */
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#if !defined(__WIN32__)
+#  include <dirent.h>
+#  include <limits.h>
+#  include <sys/stat.h>
+#  include <sys/types.h>
+#  include <unistd.h>
+#else
+#  include <windows.h>
+#  include <io.h>
+#  include <winbase.h>
+#  include <process.h>
+#endif
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+
+/*
+ * Make sure that MAXPATHLEN is defined.
+ */
+#ifndef MAXPATHLEN
+#   ifdef PATH_MAX
+#       define MAXPATHLEN PATH_MAX
+#   else
+#       define MAXPATHLEN 2048
+#   endif
+#endif
+
+#include "erl_printf.h"
+
+#ifdef __WIN32__
+/* FIXE ME config_win32.h? */
+#define HAVE_STRERROR 1
+#define snprintf _snprintf
+#endif
diff --git a/erts/etc/common/typer.c b/erts/etc/common/typer.c
index 6bae9f96b7..f13135d883 100644
--- a/erts/etc/common/typer.c
+++ b/erts/etc/common/typer.c
@@ -20,16 +20,8 @@
 /*
  * Purpose: Typer front-end.
  */
-#ifdef HAVE_CONFIG_H
-#  include "config.h"
-#endif
-
-#include "sys.h"
-#ifdef __WIN32__
-#include <winbase.h>
-#endif
 
-#include <ctype.h>
+#include "etc_common.h"
 
 #define NO 0
 #define YES 1
@@ -185,7 +177,7 @@ main(int argc, char** argv)
     }
 
     PUSH("+B");
-    PUSH2("-boot", "start_clean");
+    PUSH2("-boot", "no_dot_erlang");
     PUSH3("-run", "typer", "start");
     PUSH("-extra");
 
diff --git a/erts/etc/unix/cerl.src b/erts/etc/unix/cerl.src
index 862d6eb1d4..9dd8d85abe 100644
--- a/erts/etc/unix/cerl.src
+++ b/erts/etc/unix/cerl.src
@@ -143,29 +143,6 @@ while [ $# -gt 0 ]; do
 	    shift
 	    unset DISPLAY
 	    ;;
-	"-smp")
-	    shift
-	    if [ $# -le 0 ]; then
-		eeargs_add -smp
-	    else
-		case $1 in
-		    disable)
-			shift
-			eeargs_add -smpdisable
-			;;
-		    enable)
-			shift
-			eeargs_add -smp
-			;;
-		    *)
-			eeargs_add -smp
-		esac
-	    fi
-	    ;;
-	"-smpdisable")
-	    shift
-	    eeargs_add -smpdisable
-	    ;;
 	"-lcnt")
 	    shift
 	    cargs="$cargs -lcnt"
diff --git a/erts/etc/unix/dyn_erl.c b/erts/etc/unix/dyn_erl.c
index d6d2201648..5c7c3cad38 100644
--- a/erts/etc/unix/dyn_erl.c
+++ b/erts/etc/unix/dyn_erl.c
@@ -22,13 +22,7 @@
  * This is a C version of the erl Bourne shell script
  */
 
-#ifdef HAVE_CONFIG_H
-#  include "config.h"
-#endif
-
-#include "sys.h"
-#include <stdlib.h>
-#include <stdarg.h>
+#include "etc_common.h"
 
 #define BOOL int
 #define TRUE 1
diff --git a/erts/etc/unix/etp-commands.in b/erts/etc/unix/etp-commands.in
index 8f70f879d5..95e065b156 100644
--- a/erts/etc/unix/etp-commands.in
+++ b/erts/etc/unix/etp-commands.in
@@ -2316,40 +2316,46 @@ end
 define etp-port-sched-flags-int
 # Args: int
 #
-  if ($arg0 & 0x1)
+  if ($arg0 & (1 << 0))
     printf " in-run-queue"
   end
-  if ($arg0 & 0x2)
+  if ($arg0 & (1 << 1))
     printf " executing"
   end
-  if ($arg0 & 0x4)
+  if ($arg0 & (1 << 2))
     printf " have-tasks"
   end
-  if ($arg0 & 0x8)
+  if ($arg0 & (1 << 3))
     printf " exited"
   end
-  if ($arg0 & 0x10)
+  if ($arg0 & (1 << 4))
     printf " busy-port"
   end
-  if ($arg0 & 0x20)
+  if ($arg0 & (1 << 5))
     printf " busy-port-q"
   end
-  if ($arg0 & 0x40)
+  if ($arg0 & (1 << 6))
     printf " chk-unset-busy-port-q"
   end
-  if ($arg0 & 0x80)
+  if ($arg0 & (1 << 7))
     printf " have-busy-tasks"
   end
-  if ($arg0 & 0x100)
+  if ($arg0 & (1 << 8))
     printf " have-nosuspend-tasks"
   end
-  if ($arg0 & 0x200)
+  if ($arg0 & (1 << 9))
     printf " parallelism"
   end
-  if ($arg0 & 0x400)
+  if ($arg0 & (1 << 10))
     printf " force-sched"
   end
-  if ($arg0 & 0xfffff800)
+  if ($arg0 & (1 << 11))
+    printf " exiting"
+  end
+  if ($arg0 & (1 << 12))
+    printf " exec-imm"
+  end
+  if ($arg0 & 0xffffc000)
     printf " GARBAGE"
   end
   printf "\n"
@@ -2850,6 +2856,14 @@ define etp-run-queue-info-internal
   printf "  Pointer: (ErtsRunQueue *) %p\n", $runq
 end
 
+define etp-fds
+  if $_exitsignal == -1
+    call erts_check_io_debug(0)
+  else
+    printf "Not yet implemented for core files"
+  end
+end
+
 define etp-disasm-1
   set $code_ptr = ((BeamInstr*)$arg0)
   set $addr = *$code_ptr
@@ -4314,6 +4328,10 @@ document etp-init
 %---------------------------------------------------------------------------
 end
 
+define hook-run
+  set $_exitsignal = -1
+end
+
 etp-init
 help etp-init
 etp-show
diff --git a/erts/etc/unix/run_erl.c b/erts/etc/unix/run_erl.c
index 81a0036c99..725343d701 100644
--- a/erts/etc/unix/run_erl.c
+++ b/erts/etc/unix/run_erl.c
@@ -627,12 +627,14 @@ static void pass_on(pid_t childpid)
 	    status("Pty master read; ");
 #endif
 	    if ((len = sf_read(mfd, buf, BUFSIZ)) <= 0) {
+		int saved_errno = errno;
 		sf_close(rfd);
 		if(wfd) sf_close(wfd);
 		sf_close(mfd);
 		unlink(fifo1);
 		unlink(fifo2);
 		if (len < 0) {
+		    errno = saved_errno;
 		    if(errno == EIO)
 			ERROR0(LOG_ERR,"Erlang closed the connection.");
 		    else
@@ -1342,10 +1344,12 @@ static int sf_open(const char *path, int type, mode_t mode) {
 
     return fd;
 }
+
 static int sf_close(int fd) {
     /* "close() should not be retried after an EINTR" */
     return close(fd);
 }
+
 /* Extract any control sequences that are ment only for run_erl
  * and should not be forwarded to the pty.
  */
diff --git a/erts/lib_src/common/erl_printf.c b/erts/lib_src/common/erl_printf.c
index 3b073bcd1b..1de0f81e84 100644
--- a/erts/lib_src/common/erl_printf.c
+++ b/erts/lib_src/common/erl_printf.c
@@ -63,7 +63,7 @@ void (*erts_printf_unblock_fpe)(int) = NULL;
 #undef FWRITE
 #undef PUTC_ON_SMALL_WRITES
 
-#if defined(USE_THREADS) && defined(HAVE_FLOCKFILE)
+#if defined(HAVE_FLOCKFILE)
 #	define FLOCKFILE(FP)	flockfile(FP)
 #	define FUNLOCKFILE(FP)	funlockfile(FP)
 #	ifdef HAVE_PUTC_UNLOCKED
@@ -73,11 +73,7 @@ void (*erts_printf_unblock_fpe)(int) = NULL;
 #	ifdef HAVE_FWRITE_UNLOCKED
 #		define FWRITE	fwrite_unlocked
 #	endif
-#endif
-#if !defined(USE_THREADS) && defined(putc) && !defined(fwrite)
-#	define PUTC_ON_SMALL_WRITES
-#endif
-#if !defined(FLOCKFILE) || !defined(FUNLOCKFILE)
+#else
 #	define FLOCKFILE(FP)
 #	define FUNLOCKFILE(FP)
 #endif
diff --git a/erts/preloaded/ebin/erl_prim_loader.beam b/erts/preloaded/ebin/erl_prim_loader.beam
index af6facb5f2..2d86dd3843 100644
--- a/erts/preloaded/ebin/erl_prim_loader.beam
+++ b/erts/preloaded/ebin/erl_prim_loader.beam
diff --git a/erts/preloaded/ebin/erl_tracer.beam b/erts/preloaded/ebin/erl_tracer.beam
index 7ca25803be..7754d64a6b 100644
--- a/erts/preloaded/ebin/erl_tracer.beam
+++ b/erts/preloaded/ebin/erl_tracer.beam
diff --git a/erts/preloaded/ebin/erlang.beam b/erts/preloaded/ebin/erlang.beam
index 6fa48e8582..f0da8b5869 100644
--- a/erts/preloaded/ebin/erlang.beam
+++ b/erts/preloaded/ebin/erlang.beam
diff --git a/erts/preloaded/ebin/erts_code_purger.beam b/erts/preloaded/ebin/erts_code_purger.beam
index b7c061d9a0..655e1d2e06 100644
--- a/erts/preloaded/ebin/erts_code_purger.beam
+++ b/erts/preloaded/ebin/erts_code_purger.beam
diff --git a/erts/preloaded/ebin/erts_dirty_process_code_checker.beam b/erts/preloaded/ebin/erts_dirty_process_code_checker.beam
index 6467b1c016..2a4cb53d3e 100644
--- a/erts/preloaded/ebin/erts_dirty_process_code_checker.beam
+++ b/erts/preloaded/ebin/erts_dirty_process_code_checker.beam
diff --git a/erts/preloaded/ebin/erts_internal.beam b/erts/preloaded/ebin/erts_internal.beam
index 6691749dcb..7d2edd9845 100644
--- a/erts/preloaded/ebin/erts_internal.beam
+++ b/erts/preloaded/ebin/erts_internal.beam
diff --git a/erts/preloaded/ebin/erts_literal_area_collector.beam b/erts/preloaded/ebin/erts_literal_area_collector.beam
index fbd3249d70..bb2676a9e8 100644
--- a/erts/preloaded/ebin/erts_literal_area_collector.beam
+++ b/erts/preloaded/ebin/erts_literal_area_collector.beam
diff --git a/erts/preloaded/ebin/init.beam b/erts/preloaded/ebin/init.beam
index 1c8d0e626a..a2dd41b435 100644
--- a/erts/preloaded/ebin/init.beam
+++ b/erts/preloaded/ebin/init.beam
diff --git a/erts/preloaded/ebin/otp_ring0.beam b/erts/preloaded/ebin/otp_ring0.beam
index 73a017d981..6a03451ad5 100644
--- a/erts/preloaded/ebin/otp_ring0.beam
+++ b/erts/preloaded/ebin/otp_ring0.beam
diff --git a/erts/preloaded/ebin/prim_buffer.beam b/erts/preloaded/ebin/prim_buffer.beam
new file mode 100644
index 0000000000..06d9276247
--- /dev/null
+++ b/erts/preloaded/ebin/prim_buffer.beam
diff --git a/erts/preloaded/ebin/prim_eval.beam b/erts/preloaded/ebin/prim_eval.beam
index 7e46b79671..17c59708e7 100644
--- a/erts/preloaded/ebin/prim_eval.beam
+++ b/erts/preloaded/ebin/prim_eval.beam
diff --git a/erts/preloaded/ebin/prim_file.beam b/erts/preloaded/ebin/prim_file.beam
index 32755d5c28..902b0945c6 100644
--- a/erts/preloaded/ebin/prim_file.beam
+++ b/erts/preloaded/ebin/prim_file.beam
diff --git a/erts/preloaded/ebin/prim_inet.beam b/erts/preloaded/ebin/prim_inet.beam
index c03415c758..a42f45c180 100644
--- a/erts/preloaded/ebin/prim_inet.beam
+++ b/erts/preloaded/ebin/prim_inet.beam
diff --git a/erts/preloaded/ebin/prim_zip.beam b/erts/preloaded/ebin/prim_zip.beam
index 77d0d2edb0..1ec6870178 100644
--- a/erts/preloaded/ebin/prim_zip.beam
+++ b/erts/preloaded/ebin/prim_zip.beam
diff --git a/erts/preloaded/ebin/zlib.beam b/erts/preloaded/ebin/zlib.beam
index 4ad5f37434..7a5f4d7527 100644
--- a/erts/preloaded/ebin/zlib.beam
+++ b/erts/preloaded/ebin/zlib.beam
diff --git a/erts/preloaded/src/Makefile b/erts/preloaded/src/Makefile
index edb9f35258..a2872082f2 100644
--- a/erts/preloaded/src/Makefile
+++ b/erts/preloaded/src/Makefile
@@ -36,6 +36,7 @@ include $(ERL_TOP)/lib/kernel/vsn.mk
 PRE_LOADED_ERL_MODULES = \
 	erl_prim_loader \
 	init \
+	prim_buffer \
 	prim_file \
 	prim_inet \
 	zlib \
@@ -116,7 +117,7 @@ prim_eval.beam: prim_eval.S prim_eval.abstr
 
 # Include dependencies -- list below added by PaN
 $(EBIN)/erl_prim_loader.beam: $(KERNEL_SRC)/inet_boot.hrl $(KERNEL_INCLUDE)/file.hrl
-$(EBIN)/prim_file.beam: $(KERNEL_INCLUDE)/file.hrl
+$(EBIN)/prim_file.beam: $(KERNEL_SRC)/file_int.hrl $(KERNEL_INCLUDE)/file.hrl
 $(EBIN)/prim_inet.beam: $(KERNEL_SRC)/inet_int.hrl $(KERNEL_INCLUDE)/inet_sctp.hrl
 $(EBIN)/prim_zip.beam: zip_internal.hrl $(KERNEL_INCLUDE)/file.hrl $(STDLIB_INCLUDE)/zip.hrl
 $(EBIN)/init.erl: $(KERNEL_INCLUDE)/file.hrl
diff --git a/erts/preloaded/src/erl_prim_loader.erl b/erts/preloaded/src/erl_prim_loader.erl
index 1d09aeded9..d16fe5a0bc 100644
--- a/erts/preloaded/src/erl_prim_loader.erl
+++ b/erts/preloaded/src/erl_prim_loader.erl
@@ -151,9 +151,8 @@ start_inet(Parent) ->
     loop(State, Parent, []).
 
 start_efile(Parent) ->
-    {ok, Port} = prim_file:start(),
     %% Check that we started in a valid directory.
-    case prim_file:get_cwd(Port) of
+    case prim_file:get_cwd() of
 	{error, _} ->
 	    %% At this point in the startup, we have no error_logger at all.
 	    Report = "Invalid current directory or invalid filename "
@@ -165,7 +164,7 @@ start_efile(Parent) ->
     end,
     PS = prim_init(),
     State = #state {loader = efile,
-                    data = Port,
+                    data = noport,
                     timeout = ?EFILE_IDLE_TIMEOUT,
                     prim_state = PS},
     loop(State, Parent, []).
@@ -401,12 +400,12 @@ handle_get_cwd(State = #state{loader = inet}, Drive) ->
     ?SAFE2(inet_get_cwd(State, Drive), State).
     
 handle_stop(State = #state{loader = efile}) ->
-    efile_stop_port(State);
+    State;
 handle_stop(State = #state{loader = inet}) ->
     inet_stop_port(State).
 
-handle_exit(State = #state{loader = efile}, Who, Reason) ->
-    efile_exit_port(State, Who, Reason);
+handle_exit(State = #state{loader = efile}, _Who, _Reason) ->
+    State;
 handle_exit(State = #state{loader = inet}, Who, Reason) ->
     inet_exit_port(State, Who, Reason).
 
@@ -475,15 +474,6 @@ efile_get_cwd(#state{prim_state = PS} = State, Drive) ->
     {Res, PS2} = prim_get_cwd(PS, Drive),
     {Res, State#state{prim_state = PS2}}.
 
-efile_stop_port(#state{data=Port}=State) ->
-    prim_file:close(Port),
-    State#state{data=noport}.
-
-efile_exit_port(State, Port, Reason) when State#state.data =:= Port ->
-    exit({port_died,Reason});
-efile_exit_port(State, _Port, _Reason) ->
-    State.
-
 efile_timeout_handler(State, _Parent) ->
     prim_purge_cache(),
     State.
diff --git a/erts/preloaded/src/erlang.erl b/erts/preloaded/src/erlang.erl
index f796ea64d3..f3c83b9949 100644
--- a/erts/preloaded/src/erlang.erl
+++ b/erts/preloaded/src/erlang.erl
@@ -31,8 +31,7 @@
 -export([localtime_to_universaltime/1]).
 -export([suspend_process/1]).
 -export([min/2, max/2]).
--export([dlink/1, dunlink/1, dsend/2, dsend/3, dgroup_leader/2,
-	 dexit/2, dmonitor_node/3, dmonitor_p/2]).
+-export([dmonitor_node/3, dmonitor_p/2]).
 -export([delay_trap/2]).
 -export([set_cookie/2, get_cookie/0]).
 -export([nodes/0]).
@@ -44,9 +43,13 @@
 -export([memory/0, memory/1]).
 -export([alloc_info/1, alloc_sizes/1]).
 
--export([gather_sched_wall_time_result/1,
-	 await_sched_wall_time_modifications/2,
-	 gather_gc_info_result/1]).
+-export([gather_gc_info_result/1]).
+
+-export([dist_ctrl_input_handler/2,
+         dist_ctrl_put_data/2,
+         dist_ctrl_get_data/1,
+         dist_ctrl_get_data_notification/1,
+         dist_get_stat/1]).
 
 -deprecated([now/0]).
 
@@ -87,6 +90,10 @@
 
 -export_type([prepared_code/0]).
 
+-opaque dist_handle() :: atom().
+
+-export_type([dist_handle/0]).
+
 -type iovec() :: [binary()].
 
 -export_type([iovec/0]).
@@ -114,7 +121,7 @@
 -export([crc32/2, crc32_combine/3, date/0, decode_packet/3]).
 -export([delete_element/2]).
 -export([delete_module/1, demonitor/1, demonitor/2, display/1]).
--export([display_nl/0, display_string/1, dist_exit/3, erase/0, erase/1]).
+-export([display_nl/0, display_string/1, erase/0, erase/1]).
 -export([error/1, error/2, exit/1, exit/2, external_size/1]).
 -export([external_size/2, finish_after_on_load/2, finish_loading/1, float/1]).
 -export([float_to_binary/1, float_to_binary/2,
@@ -417,9 +424,11 @@ binary_to_term(_Binary) ->
     erlang:nif_error(undefined).
 
 %% binary_to_term/2
--spec binary_to_term(Binary, Opts) -> term() when
+-spec binary_to_term(Binary, Opts) -> term() | {term(), Used} when
       Binary :: ext_binary(),
-      Opts :: [safe].
+      Opt :: safe | used,
+      Opts :: [Opt],
+      Used :: pos_integer().
 binary_to_term(_Binary, _Opts) ->
     erlang:nif_error(undefined).
 
@@ -692,14 +701,6 @@ display_nl() ->
 display_string(_P1) ->
     erlang:nif_error(undefined).
 
-%% dist_exit/3
--spec erlang:dist_exit(P1, P2, P3) -> true when
-      P1 :: pid(),
-      P2 :: kill | noconnection | normal,
-      P3 :: pid() | port().
-dist_exit(_P1, _P2, _P3) ->
-    erlang:nif_error(undefined).
-
 %% dt_append_vm_tag_data/1
 -spec erlang:dt_append_vm_tag_data(IoData) -> IoDataRet when
       IoData :: iodata(),
@@ -1651,7 +1652,7 @@ setnode(_P1, _P2) ->
     erlang:nif_error(undefined).
 
 %% setnode/3
--spec erlang:setnode(P1, P2, P3) -> true when
+-spec erlang:setnode(P1, P2, P3) -> dist_handle() when
       P1 :: atom(),
       P2 :: port(),
       P3 :: {term(), term(), term(), term()}.
@@ -2100,7 +2101,7 @@ nodes(_Arg) ->
            | stream
            | {line, L :: non_neg_integer()}
            | {cd, Dir :: string() | binary()}
-           | {env, Env :: [{Name :: string(), Val :: string() | false}]}
+           | {env, Env :: [{Name :: os:env_var_name(), Val :: os:env_var_value() | false}]}
            | {args, [string() | binary()]}
            | {arg0, string() | binary()}
            | exit_status
@@ -2334,7 +2335,8 @@ spawn_opt(_Tuple) ->
       MSAcc_Thread :: #{ type := MSAcc_Thread_Type,
                         id := MSAcc_Thread_Id,
                         counters := MSAcc_Counters},
-      MSAcc_Thread_Type :: scheduler | async | aux,
+      MSAcc_Thread_Type :: async | aux | dirty_io_scheduler
+                         | dirty_cpu_scheduler | poll | scheduler,
       MSAcc_Thread_Id :: non_neg_integer(),
       MSAcc_Counters :: #{ MSAcc_Thread_State => non_neg_integer() },
       MSAcc_Thread_State :: alloc | aux | bif | busy_wait | check_io |
@@ -3214,33 +3216,51 @@ port_get_data(_Port) ->
     erlang:nif_error(undefined).
 
 %%
-%% If the emulator wants to perform a distributed command and
-%% a connection is not established to the actual node the following 
-%% functions are called in order to set up the connection and then
-%% reactivate the command.
+%% Distribution channel management
 %%
 
--spec erlang:dlink(pid() | port()) -> 'true'.
-dlink(Pid) ->
-    case net_kernel:connect(erlang:node(Pid)) of
-	true -> erlang:link(Pid);
-	false -> erlang:dist_exit(erlang:self(), noconnection, Pid), true
-    end.
+-spec erlang:dist_ctrl_input_handler(DHandle, InputHandler) -> 'ok' when
+      DHandle :: dist_handle(),
+      InputHandler :: pid().
 
-%% Can this ever happen?
--spec erlang:dunlink(identifier()) -> 'true'.
-dunlink(Pid) ->
-    case net_kernel:connect(erlang:node(Pid)) of
-	true -> erlang:unlink(Pid);
-	false -> true
-    end.
+dist_ctrl_input_handler(_DHandle, _InputHandler) ->
+    erlang:nif_error(undefined).
 
-dmonitor_node(Node, Flag, []) ->
-    case net_kernel:connect(Node) of
-	true -> erlang:monitor_node(Node, Flag, []);
-	false -> erlang:self() ! {nodedown, Node}, true
-    end;
+-spec erlang:dist_ctrl_put_data(DHandle, Data) -> 'ok' when
+      DHandle :: dist_handle(),
+      Data :: iodata().
+
+dist_ctrl_put_data(_DHandle, _Data) ->
+    erlang:nif_error(undefined).
+
+-spec erlang:dist_ctrl_get_data(DHandle) -> Data | 'none' when
+      DHandle :: dist_handle(),
+      Data :: iodata().
+
+dist_ctrl_get_data(_DHandle) ->
+    erlang:nif_error(undefined).
+
+-spec erlang:dist_ctrl_get_data_notification(DHandle) -> 'ok' when
+      DHandle :: dist_handle().
+
+dist_ctrl_get_data_notification(_DHandle) ->
+    erlang:nif_error(undefined).
+
+-spec erlang:dist_get_stat(DHandle) -> Res when
+      DHandle :: dist_handle(),
+      InputPackets :: non_neg_integer(),
+      OutputPackets :: non_neg_integer(),
+      PendingOutputPackets :: boolean(),
+      Res :: {'ok', InputPackets, OutputPackets, PendingOutputPackets}.
 
+dist_get_stat(_DHandle) ->
+    erlang:nif_error(undefined).
+
+
+dmonitor_node(Node, _Flag, []) ->
+    %% Only called when auto-connect attempt failed early in VM
+    erlang:self() ! {nodedown, Node},
+    true;
 dmonitor_node(Node, Flag, Opts) ->
     case lists:member(allow_passive_connect, Opts) of
 	true ->
@@ -3252,71 +3272,12 @@ dmonitor_node(Node, Flag, Opts) ->
 	    dmonitor_node(Node,Flag,[])
     end.
 
-dgroup_leader(Leader, Pid) ->
-    case net_kernel:connect(erlang:node(Pid)) of
-	true -> erlang:group_leader(Leader, Pid);
-	false -> true  %% bad arg ?
-    end.
-
-dexit(Pid, Reason) -> 
-    case net_kernel:connect(erlang:node(Pid)) of
-	true -> erlang:exit(Pid, Reason);
-	false -> true
-    end.
-
-dsend(Pid, Msg) when erlang:is_pid(Pid) ->
-    case net_kernel:connect(erlang:node(Pid)) of
-	true -> erlang:send(Pid, Msg);
-	false -> Msg
-    end;
-dsend(Port, Msg) when erlang:is_port(Port) ->
-    case net_kernel:connect(erlang:node(Port)) of
-	true -> erlang:send(Port, Msg);
-	false -> Msg
-    end;
-dsend({Name, Node}, Msg) ->
-    case net_kernel:connect(Node) of
-	true -> erlang:send({Name,Node}, Msg);
-	false -> Msg;
-	ignored -> Msg				% Not distributed.
-    end.
-
-dsend(Pid, Msg, Opts) when erlang:is_pid(Pid) ->
-    case net_kernel:connect(erlang:node(Pid)) of
-	true -> erlang:send(Pid, Msg, Opts);
-	false -> ok
-    end;
-dsend(Port, Msg, Opts) when erlang:is_port(Port) ->
-    case net_kernel:connect(erlang:node(Port)) of
-	true -> erlang:send(Port, Msg, Opts);
-	false -> ok
-    end;
-dsend({Name, Node}, Msg, Opts) ->
-    case net_kernel:connect(Node) of
-	true -> erlang:send({Name,Node}, Msg, Opts);
-	false -> ok;
-	ignored -> ok				% Not distributed.
-    end.
-
 -spec erlang:dmonitor_p('process', pid() | {atom(),atom()}) -> reference().
 dmonitor_p(process, ProcSpec) ->
-    %% ProcSpec = pid() | {atom(),atom()}
-    %% ProcSpec CANNOT be an atom because a locally registered process
-    %% is never handled here.
-    Node = case ProcSpec of
-	       {S,N} when erlang:is_atom(S),
-                          erlang:is_atom(N),
-                          N =/= erlang:node() -> N;
-	       _ when erlang:is_pid(ProcSpec) -> erlang:node(ProcSpec)
-	   end,
-    case net_kernel:connect(Node) of
-	true ->
-	    erlang:monitor(process, ProcSpec);
-	false ->
-	    Ref = erlang:make_ref(),
-	    erlang:self() ! {'DOWN', Ref, process, ProcSpec, noconnection},
-	    Ref
-    end.
+    %% Only called when auto-connect attempt failed early in VM
+    Ref = erlang:make_ref(),
+    erlang:self() ! {'DOWN', Ref, process, ProcSpec, noconnection},
+    Ref.
 
 %%
 %% Trap function used when modified timing has been enabled.
@@ -4017,38 +3978,6 @@ receive_allocator(Ref, N, Acc) ->
 	    receive_allocator(Ref, N-1, insert_info(InfoList, Acc))
     end.
 
--spec erlang:await_sched_wall_time_modifications(Ref, Result) -> boolean() when
-      Ref :: reference(),
-      Result :: boolean().
-
-await_sched_wall_time_modifications(Ref, Result) ->
-    sched_wall_time(Ref, erlang:system_info(schedulers)),
-    Result.
-
--spec erlang:gather_sched_wall_time_result(Ref) -> [{pos_integer(),
-						     non_neg_integer(),
-						     non_neg_integer()}] when
-      Ref :: reference().
-
-gather_sched_wall_time_result(Ref) when erlang:is_reference(Ref) ->
-    sched_wall_time(Ref, erlang:system_info(schedulers), []).
-
-sched_wall_time(_Ref, 0) ->
-    ok;
-sched_wall_time(Ref, N) ->
-    receive Ref -> sched_wall_time(Ref, N-1) end.
-
-sched_wall_time(_Ref, 0, Acc) ->
-    Acc;
-sched_wall_time(Ref, N, undefined) ->
-    receive {Ref, _} -> sched_wall_time(Ref, N-1, undefined) end;
-sched_wall_time(Ref, N, Acc) ->
-    receive
-	{Ref, undefined} -> sched_wall_time(Ref, N-1, undefined);
-	{Ref, SWTL} when erlang:is_list(SWTL) -> sched_wall_time(Ref, N-1, Acc ++ SWTL);
-	{Ref, SWT} -> sched_wall_time(Ref, N-1, [SWT|Acc])
-    end.
-
 -spec erlang:gather_gc_info_result(Ref) ->
    {number(),number(),0} when Ref :: reference().
 
diff --git a/erts/preloaded/src/erts.app.src b/erts/preloaded/src/erts.app.src
index 7ab06164b4..338f168158 100644
--- a/erts/preloaded/src/erts.app.src
+++ b/erts/preloaded/src/erts.app.src
@@ -28,6 +28,7 @@
 		init,
 		otp_ring0,
 		erts_code_purger,
+		prim_buffer,
 		prim_eval,
 		prim_file,
 		prim_inet,
@@ -37,7 +38,7 @@
 	{registered, []},
 	{applications, []},
 	{env, []},
-	{runtime_dependencies, ["stdlib-3.0", "kernel-5.0", "sasl-3.0.1"]}
+	{runtime_dependencies, ["stdlib-3.5", "kernel-6.0", "sasl-3.0.1"]}
     ]}.
 
 %% vim: ft=erlang
diff --git a/erts/preloaded/src/erts_internal.erl b/erts/preloaded/src/erts_internal.erl
index 26fb1458af..a083e9ac2f 100644
--- a/erts/preloaded/src/erts_internal.erl
+++ b/erts/preloaded/src/erts_internal.erl
@@ -32,7 +32,7 @@
 -export([await_port_send_result/3]).
 -export([cmp_term/2]).
 -export([map_to_tuple_keys/1, term_type/1, map_hashmap_children/1,
-         maps_to_list/2]).
+         map_next/3]).
 -export([open_port/2, port_command/3, port_connect/2, port_close/1,
 	 port_control/3, port_call/3, port_info/1, port_info/2]).
 
@@ -61,6 +61,15 @@
 
 -export([trace/3, trace_pattern/3]).
 
+-export([dist_ctrl_put_data/2]).
+
+-export([new_connection/1]).
+-export([abort_connection/2]).
+
+-export([scheduler_wall_time/1, system_flag_scheduler_wall_time/1,
+         gather_sched_wall_time_result/1,
+	 await_sched_wall_time_modifications/2]).
+
 %% Auto import name clash
 -export([check_process_code/1]).
 
@@ -365,20 +374,23 @@ term_type(_T) ->
 map_hashmap_children(_M) ->
     erlang:nif_error(undefined).
 
+%% return the next assoc in the iterator and a new iterator
+-spec map_next(I, M, A) -> {K,V,NI} | list() when
+      I :: non_neg_integer(),
+      M :: map(),
+      K :: term(),
+      V :: term(),
+      A :: iterator | list(),
+      NI :: maps:iterator().
+
+map_next(_I, _M, _A) ->
+    erlang:nif_error(undefined).
+
 -spec erts_internal:flush_monitor_messages(Ref, Multi, Res) -> term() when
       Ref :: reference(),
       Multi :: boolean(),
       Res :: term().
 
-%% return a list of key value pairs, at most of length N
--spec maps_to_list(M,N) -> Pairs when
-    M :: map(),
-    N :: integer(),
-    Pairs :: list().
-
-maps_to_list(_M, _N) ->
-    erlang:nif_error(undefined).
-
 %% erlang:demonitor(Ref, [flush]) traps to
 %% erts_internal:flush_monitor_messages(Ref, Res) when
 %% it needs to flush monitor messages.
@@ -461,3 +473,98 @@ trace(_PidSpec, _How, _FlagList) ->
       FlagList :: [ ].
 trace_pattern(_MFA, _MatchSpec, _FlagList) ->
     erlang:nif_error(undefined).
+
+-spec dist_ctrl_put_data(DHandle, Data) -> 'ok' when
+      DHandle :: erlang:dist_handle(),
+      Data :: iolist().
+
+dist_ctrl_put_data(DHandle, IoList) ->
+    %%
+    %% Helper for erlang:dist_ctrl_put_data/2
+    %%
+    %% erlang:dist_ctrl_put_data/2 traps to
+    %% this function if second argument is
+    %% a list...
+    %%
+    try
+        Binary = erlang:iolist_to_binary(IoList),
+        %% Restart erlang:dist_ctrl_put_data/2
+        %% with the iolist converted to a binary...
+        erlang:dist_ctrl_put_data(DHandle, Binary)
+    catch
+        Class : Reason ->
+            %% Throw exception as if thrown from
+            %% erlang:dist_ctrl_put_data/2 ...
+            RootST = try erlang:error(Reason)
+                     catch
+                         error:Reason ->
+                             case erlang:get_stacktrace() of
+                                 [] -> [];
+                                 ST -> tl(ST)
+                             end
+                     end,
+	    StackTrace = [{erlang, dist_ctrl_put_data,
+                           [DHandle, IoList], []}
+                          | RootST],
+	    erlang:raise(Class, Reason, StackTrace)
+    end.
+
+
+-spec erts_internal:new_connection(Node) -> ConnId when
+      Node :: atom(),
+      ConnId :: {integer(), erlang:dist_handle()}.
+new_connection(_Node) ->
+    erlang:nif_error(undefined).
+
+-spec erts_internal:abort_connection(Node, ConnId) -> boolean() when
+      Node :: atom(),
+      ConnId :: {integer(), erlang:dist_handle()}.
+abort_connection(_Node, _ConnId) ->
+    erlang:nif_error(undefined).
+
+%% Scheduler wall time
+
+-spec erts_internal:system_flag_scheduler_wall_time(Enable) -> boolean() when
+      Enable :: boolean().
+
+system_flag_scheduler_wall_time(Bool) ->
+    kernel_refc:scheduler_wall_time(Bool).
+
+
+-spec erts_internal:await_sched_wall_time_modifications(Ref, Result) -> boolean() when
+      Ref :: reference(),
+      Result :: boolean().
+
+-spec erts_internal:scheduler_wall_time(Enable) -> boolean() when
+      Enable :: boolean().
+
+scheduler_wall_time(_Enable) ->
+    erlang:nif_error(undefined).
+
+await_sched_wall_time_modifications(Ref, Result) ->
+    sched_wall_time(Ref, erlang:system_info(schedulers)),
+    Result.
+
+-spec erts_internal:gather_sched_wall_time_result(Ref) -> [{pos_integer(),
+						     non_neg_integer(),
+						     non_neg_integer()}] when
+      Ref :: reference().
+
+gather_sched_wall_time_result(Ref) when erlang:is_reference(Ref) ->
+    sched_wall_time(Ref, erlang:system_info(schedulers), []).
+
+sched_wall_time(_Ref, 0) ->
+    ok;
+sched_wall_time(Ref, N) ->
+    receive Ref -> sched_wall_time(Ref, N-1) end.
+
+sched_wall_time(_Ref, 0, Acc) ->
+    Acc;
+sched_wall_time(Ref, N, undefined) ->
+    receive {Ref, _} -> sched_wall_time(Ref, N-1, undefined) end;
+sched_wall_time(Ref, N, Acc) ->
+    receive
+	{Ref, undefined} -> sched_wall_time(Ref, N-1, undefined);
+	{Ref, SWTL} when erlang:is_list(SWTL) -> sched_wall_time(Ref, N-1, Acc ++ SWTL);
+	{Ref, SWT} -> sched_wall_time(Ref, N-1, [SWT|Acc])
+    end.
diff --git a/erts/preloaded/src/init.erl b/erts/preloaded/src/init.erl
index 34a9f6b8b9..679a2241d2 100644
--- a/erts/preloaded/src/init.erl
+++ b/erts/preloaded/src/init.erl
@@ -200,10 +200,11 @@ boot(BootArgs) ->
     register(init, self()),
     process_flag(trap_exit, true),
 
-    %% Load the zlib nif
+    %% Load the static nifs
     zlib:on_load(),
-    %% Load the tracer nif
     erl_tracer:on_load(),
+    prim_buffer:on_load(),
+    prim_file:on_load(),
 
     {Start0,Flags,Args} = parse_boot_args(BootArgs),
     %% We don't get to profile parsing of BootArgs
diff --git a/erts/preloaded/src/prim_buffer.erl b/erts/preloaded/src/prim_buffer.erl
new file mode 100644
index 0000000000..e0d35a6792
--- /dev/null
+++ b/erts/preloaded/src/prim_buffer.erl
@@ -0,0 +1,140 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(prim_buffer).
+
+-export([on_load/0]).
+
+%% This is a mutable binary buffer that helps break out buffering logic from
+%% NIFs/drivers, which is often the only thing that prevents the C code from
+%% being reduced to bare system call wrappers.
+%%
+%% All operations in this file are thread-unsafe and risk crashing the emulator
+%% if you're not careful.
+
+-export([new/0, size/1, wipe/1, read/2, read_iovec/2, write/2, skip/2]).
+
+-export([find_byte_index/2]).
+
+-export([try_lock/1, unlock/1]).
+
+-type prim_buffer() :: term().
+
+%% Controls when to copy rather than extract sub-binaries from the buffer,
+%% reducing the risk of small reads keeping a large binary alive.
+-define(COPYING_READ_LIMIT, 512).
+
+%% Reads that fit into heap binaries are always copied since the cost of
+%% peeking binaries that short is largely equivalent to copying.
+-define(ERL_ONHEAP_BIN_LIMIT, 64).
+
+on_load() ->
+    case erlang:load_nif(atom_to_list(?MODULE), 0) of
+        ok -> ok
+    end.
+
+-spec new() -> prim_buffer().
+new() ->
+    erlang:nif_error(undef).
+
+-spec size(Buffer :: prim_buffer()) -> non_neg_integer().
+size(_Buffer) ->
+    erlang:nif_error(undef).
+
+%% Reads data as a binary from the front of the buffer. This will almost always
+%% result in copying so it should be avoided unless you absolutely must have a
+%% binary.
+-spec read(Buffer :: prim_buffer(), Size :: non_neg_integer()) -> binary().
+read(Buffer, Size) when Size =< ?ERL_ONHEAP_BIN_LIMIT ->
+    copying_read(Buffer, Size);
+read(Buffer, Size) when Size > ?ERL_ONHEAP_BIN_LIMIT ->
+    iolist_to_binary(read_iovec(Buffer, Size)).
+
+%% Reads data as an erlang:iovec() binary from the front of the buffer,
+%% avoiding copying if reasonable.
+-spec read_iovec(Buffer, Size) -> IOVec when
+      Buffer :: prim_buffer(),
+      Size :: non_neg_integer(),
+      IOVec :: erlang:iovec().
+read_iovec(Buffer, Size) when Size =< ?ERL_ONHEAP_BIN_LIMIT ->
+    [copying_read(Buffer, Size)];
+read_iovec(Buffer, Size) when Size > ?ERL_ONHEAP_BIN_LIMIT ->
+    Head = peek_head(Buffer),
+    HeadSize = byte_size(Head),
+    if
+        (HeadSize - Size) > ?COPYING_READ_LIMIT, Size =< ?COPYING_READ_LIMIT ->
+            [copying_read(Buffer, Size)];
+        HeadSize > Size ->
+            skip(Buffer, Size),
+            {First, _Rest} = split_binary(Head, Size),
+            [First];
+        HeadSize < Size ->
+            skip(Buffer, HeadSize),
+            [Head | read_iovec(Buffer, Size - HeadSize)];
+        HeadSize =:= Size ->
+            skip(Buffer, Size),
+            [Head]
+    end.
+
+%% Writes an erlang:iovec() to the back of the buffer.
+-spec write(Buffer :: prim_buffer(), IOVec :: erlang:iovec()) -> ok.
+write(_Buffer, _IOVec) ->
+    erlang:nif_error(undef).
+
+%% Removes data from the front of the buffer without reading it.
+-spec skip(Buffer :: prim_buffer(), Size :: non_neg_integer()) -> ok.
+skip(_Buffer, _Size) ->
+    erlang:nif_error(undef).
+
+-spec wipe(Buffer :: prim_buffer()) -> ok.
+wipe(Buffer) ->
+    skip(Buffer, prim_buffer:size(Buffer)).
+
+%% Finds the start-index of the first occurence of Needle, for implementing
+%% read_line and similar.
+-spec find_byte_index(Buffer, Needle) -> Result when
+      Buffer :: prim_buffer(),
+      Needle :: non_neg_integer(),
+      Result :: {ok, non_neg_integer()} |
+                not_found.
+find_byte_index(_Buffer, _Needle) ->
+    erlang:nif_error(undef).
+
+%% Attempts to take a unique lock on the buffer. Failure handling is left to
+%% the user.
+-spec try_lock(Buffer :: prim_buffer()) -> acquired | busy.
+try_lock(_Buffer) ->
+    erlang:nif_error(undef).
+
+-spec unlock(Buffer :: prim_buffer()) -> ok.
+unlock(_Buffer) ->
+    erlang:nif_error(undef).
+
+%% Unexported helper functions:
+
+%% Reads data from the front of the buffer, returning a copy of the data to
+%% avoid holding references.
+-spec copying_read(Buffer :: prim_buffer(), Size :: non_neg_integer()) -> binary().
+copying_read(_Buffer, _Size) ->
+    erlang:nif_error(undef).
+
+%% Returns the binary at the front of the buffer without modifying the buffer.
+-spec peek_head(Buffer :: prim_buffer()) -> binary().
+peek_head(_Buffer) ->
+    erlang:nif_error(undef).
diff --git a/erts/preloaded/src/prim_file.erl b/erts/preloaded/src/prim_file.erl
index ab5359ebbc..35042a7c72 100644
--- a/erts/preloaded/src/prim_file.erl
+++ b/erts/preloaded/src/prim_file.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2000-2016. All Rights Reserved.
+%% Copyright Ericsson AB 2000-2017. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -19,147 +19,45 @@
 %%
 -module(prim_file).
 
-%% Interface module to the file driver.
+-export([on_load/0]).
 
+-export([open/2, close/1,
+         sync/1, datasync/1, truncate/1, advise/4, allocate/3,
+         read_line/1, read/2, write/2, position/2,
+         pread/2, pread/3, pwrite/2, pwrite/3]).
 
+%% OTP internal.
+-export([ipread_s32bu_p32bu/3, sendfile/8, altname/1, get_handle/1]).
 
-%%% Interface towards a single file's contents. Uses ?FD_DRV.
+-export([read_file/1, write_file/2]).
 
-%% Generic file contents operations
--export([open/2, close/1, datasync/1, sync/1, advise/4, position/2, truncate/1,
-	 write/2, pwrite/2, pwrite/3, read/2, read_line/1, pread/2, pread/3,
-	 copy/3, sendfile/8, allocate/3]).
+-export([read_link/1, read_link_all/1,
+         read_link_info/1, read_link_info/2,
+         read_file_info/1, read_file_info/2,
+         write_file_info/2, write_file_info/3]).
 
-%% Specialized file operations
--export([open/1, open/3]).
--export([read_file/1, read_file/2, write_file/2]).
--export([ipread_s32bu_p32bu/3]).
+-export([list_dir/1, list_dir_all/1]).
 
+-export([get_cwd/0, get_cwd/1, set_cwd/1,
+         delete/1, rename/2,
+         make_dir/1, del_dir/1,
+         make_link/2, make_symlink/2]).
 
-
-%%% Interface towards file system and metadata. Uses ?DRV.
-
-%% Takes an optional port (opens a ?DRV port per default) as first argument.
--export([get_cwd/0, get_cwd/1, get_cwd/2, 
-	 set_cwd/1, set_cwd/2,
-	 delete/1, delete/2, 
-	 rename/2, rename/3, 
-	 make_dir/1, make_dir/2,
-	 del_dir/1, del_dir/2,
-	 read_file_info/1, read_file_info/2, read_file_info/3,
-	 altname/1, altname/2,
-	 write_file_info/2, write_file_info/3, write_file_info/4,
-	 make_link/2, make_link/3,
-	 make_symlink/2, make_symlink/3,
-	 read_link/1, read_link/2, read_link_all/1, read_link_all/2,
-	 read_link_info/1, read_link_info/2, read_link_info/3,
-	 list_dir/1, list_dir/2, list_dir_all/1, list_dir_all/2]).
-%% How to start and stop the ?DRV port.
--export([start/0, stop/1]).
-
-%% Debug exports
--export([open_int/4, open_mode/1, open_mode/4]).
-
-%%%-----------------------------------------------------------------
-%%% Includes and defines
-
--include("file.hrl").
-
--define(DRV,    "efile").
--define(FD_DRV, "efile").
-
+-define(MIN_READLINE_SIZE, 256).
 -define(LARGEFILESIZE, (1 bsl 63)).
 
-%% Driver commands
--define(FILE_OPEN,             1).
--define(FILE_READ,             2).
--define(FILE_LSEEK,            3).
--define(FILE_WRITE,            4).
--define(FILE_FSTAT,            5).
--define(FILE_PWD,              6).
--define(FILE_READDIR,          7).
--define(FILE_CHDIR,            8).
--define(FILE_FSYNC,            9).
--define(FILE_MKDIR,            10).
--define(FILE_DELETE,           11).
--define(FILE_RENAME,           12).
--define(FILE_RMDIR,            13).
--define(FILE_TRUNCATE,         14).
--define(FILE_READ_FILE,        15).
--define(FILE_WRITE_INFO,       16).
--define(FILE_LSTAT,            19).
--define(FILE_READLINK,         20).
--define(FILE_LINK,             21).
--define(FILE_SYMLINK,          22).
--define(FILE_CLOSE,            23).
--define(FILE_PWRITEV,          24).
--define(FILE_PREADV,           25).
--define(FILE_SETOPT,           26).
--define(FILE_IPREAD,           27).
--define(FILE_ALTNAME,          28).
--define(FILE_READ_LINE,        29).
--define(FILE_FDATASYNC,        30).
--define(FILE_ADVISE,           31).
--define(FILE_SENDFILE,         32).
--define(FILE_ALLOCATE,         33).
-
-%% Driver responses
--define(FILE_RESP_OK,          0).
--define(FILE_RESP_ERROR,       1).
--define(FILE_RESP_DATA,        2).
--define(FILE_RESP_NUMBER,      3).
--define(FILE_RESP_INFO,        4).
--define(FILE_RESP_NUMERR,      5).
--define(FILE_RESP_LDATA,       6).
--define(FILE_RESP_N2DATA,      7).
--define(FILE_RESP_EOF,         8).
--define(FILE_RESP_FNAME,       9).
--define(FILE_RESP_ALL_DATA,   10).
--define(FILE_RESP_LFNAME,     11).
-
-%% Open modes for the driver's open function.
--define(EFILE_MODE_READ,       1).
--define(EFILE_MODE_WRITE,      2).
--define(EFILE_MODE_READ_WRITE, 3).  
--define(EFILE_MODE_APPEND,     4).
--define(EFILE_COMPRESSED,      8).
--define(EFILE_MODE_EXCL,       16).
-%% Note: bit 5 (32) is used internally for VxWorks
--define(EFILE_MODE_SYNC,       64).
-
-%% Use this mask to get just the mode bits to be passed to the driver.
--define(EFILE_MODE_MASK, 127).
-
-%% Seek modes for the driver's seek function.
--define(EFILE_SEEK_SET, 0).
--define(EFILE_SEEK_CUR, 1).
--define(EFILE_SEEK_END, 2).
-
-%% Options
--define(FILE_OPT_DELAYED_WRITE, 0).
--define(FILE_OPT_READ_AHEAD,    1).
-
-%% IPREAD variants
--define(IPREAD_S32BU_P32BU, 0).
-
-%% POSIX file advises
--define(POSIX_FADV_NORMAL,     0).
--define(POSIX_FADV_RANDOM,     1).
--define(POSIX_FADV_SEQUENTIAL, 2).
--define(POSIX_FADV_WILLNEED,   3).
--define(POSIX_FADV_DONTNEED,   4).
--define(POSIX_FADV_NOREUSE,    5).
-
-%% Sendfile flags
--define(EFILE_SENDFILE_USE_THREADS, 1).
+-export([copy/3]).
 
+-include("file_int.hrl").
+
+-type prim_file_ref() :: term().
 
 %%% BIFs
 
 -export([internal_name2native/1,
          internal_native2name/1,
          internal_normalize_utf8/1,
-	 is_translatable/1]).
+         is_translatable/1]).
 
 -type prim_file_name() :: string() | unicode:unicode_binary().
 -type prim_file_name_error() :: 'error' | 'ignore' | 'warning'.
@@ -185,1316 +83,733 @@ internal_normalize_utf8(_) ->
 is_translatable(_) ->
     erlang:nif_error(undefined).
 
-%%% End of BIFs
-
-%%%-----------------------------------------------------------------
-%%% Functions operating on a file through a handle. ?FD_DRV.
-%%%
-%%% Generic file contents operations.
-%%%
-%%% Supposed to be called by applications through module file.
-
-
-%% Opens a file using the driver port Port. Returns {error, Reason}
-%% | {ok, FileDescriptor}
-open(Port, File, ModeList) when is_port(Port), 
-                                (is_list(File) orelse is_binary(File)), 
-                                is_list(ModeList) ->
-    case open_mode(ModeList) of
-	{Mode, _Portopts, _Setopts} ->
-	    open_int(Port, File, Mode, []);
-	Reason ->
-	    {error, Reason}
-    end;
-open(_,_,_) ->
-    {error, badarg}.
-
-%% Opens a file. Returns {error, Reason} | {ok, FileDescriptor}.
-open(File, ModeList) when (is_list(File) orelse is_binary(File)), 
-			  is_list(ModeList) ->
-    case open_mode(ModeList) of
-	{Mode, Portopts, Setopts} ->
-	    open_int({?FD_DRV, Portopts},File, Mode, Setopts);
-	Reason ->
-	    {error, Reason}
-    end;
-open(_, _) ->
-    {error, badarg}.
+%%
 
-%% Opens a port that can be used for open/3 or read_file/2.
-%% Returns {ok, Port} | {error, Reason}.
-open(Portopts) when is_list(Portopts) ->
-    drv_open(?FD_DRV, [binary|Portopts]);
-open(_) ->
-    {error, badarg}.
+%% Returns {error, Reason} | {ok, BytesCopied}
+copy(#file_descriptor{module = ?MODULE} = Source,
+     #file_descriptor{module = ?MODULE} = Dest,
+     Length)
+  when is_integer(Length), Length >= 0;
+       is_atom(Length) ->
+    %% XXX Should be moved down to the driver for optimization.
+    file:copy_opened(Source, Dest, Length).
 
-open_int({Driver, Portopts}, File, Mode, Setopts) ->
-    case drv_open(Driver, Portopts) of
-	{ok, Port} ->
-	    open_int(Port, File, Mode, Setopts);
-	{error, _} = Error ->
-	    Error
-    end;
-open_int(Port, File, Mode, Setopts) ->
-    M = Mode band ?EFILE_MODE_MASK,
-    case drv_command(Port, [<<?FILE_OPEN, M:32>>, pathname(File)]) of
-	{ok, Number} ->
-	    open_int_setopts(Port, Number, Setopts);
-	Error ->
-	    drv_close(Port),
-	    Error
-    end.
+on_load() ->
+    ok = erlang:load_nif(atom_to_list(?MODULE), 0).
 
-open_int_setopts(Port, Number, []) ->
-    {ok, #file_descriptor{module = ?MODULE, data = {Port, Number}}};    
-open_int_setopts(Port, Number, [Cmd | Tail]) ->
-    case drv_command(Port, Cmd) of
-	ok ->
-	    open_int_setopts(Port, Number, Tail);
-	Error ->
-	    drv_close(Port),
-	    Error
+open(Name, Modes) ->
+    %% The try/catch pattern seen here is used throughout the file to adhere to
+    %% the public file interface, which has leaked through for ages because of
+    %% "raw files."
+    try open_nif(encode_path(Name), Modes) of
+        {ok, Ref} -> {ok, make_fd(Ref, Modes)};
+        {error, Reason} -> {error, Reason}
+    catch
+        error:badarg -> {error, badarg}
     end.
 
+make_fd(FRef, Modes) ->
+    #file_descriptor{module = ?MODULE, data = build_fd_data(FRef, Modes) }.
 
-
-%% Returns ok.
-
-close(#file_descriptor{module = ?MODULE, data = {Port, _}}) ->
-    case drv_command(Port, <<?FILE_CLOSE>>) of
-	ok ->
-	    drv_close(Port);
-	Error ->
-	    Error
-    end;
-%% Closes a port opened with open/1.
-close(Port) when is_port(Port) ->
-    drv_close(Port).
-
--define(ADVISE(Offs, Len, Adv),
-	<<?FILE_ADVISE, Offs:64/signed, Len:64/signed,
-	  Adv:32/signed>>).
-
-%% Returns {error, Reason} | ok.
-advise(#file_descriptor{module = ?MODULE, data = {Port, _}},
-       Offset, Length, Advise) ->
-    case Advise of
-	normal ->
-	    Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_NORMAL),
-	    drv_command(Port, Cmd);
-	random ->
-	    Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_RANDOM),
-	    drv_command(Port, Cmd);
-	sequential ->
-	    Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_SEQUENTIAL),
-	    drv_command(Port, Cmd);
-	will_need ->
-	    Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_WILLNEED),
-	    drv_command(Port, Cmd);
-	dont_need ->
-	    Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_DONTNEED),
-	    drv_command(Port, Cmd);
-	no_reuse ->
-	    Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_NOREUSE),
-	    drv_command(Port, Cmd);
-	_ ->
-	    {error, einval}
+close(Fd) ->
+    try
+        #{ handle := FRef } = get_fd_data(Fd),
+        close_nif(FRef)
+    catch
+        error:badarg -> {error, badarg}
     end.
 
-%% Returns {error, Reason} | ok.
-allocate(#file_descriptor{module = ?MODULE, data = {Port, _}}, Offset, Length) ->
-    Cmd = <<?FILE_ALLOCATE, Offset:64/signed, Length:64/signed>>,
-    drv_command(Port, Cmd).
-
-%% Returns {error, Reason} | ok.
-write(#file_descriptor{module = ?MODULE, data = {Port, _}}, Bytes) ->
-    case drv_command_nt(Port, [?FILE_WRITE,erlang:dt_prepend_vm_tag_data(Bytes)],undefined) of
-	{ok, _Size} ->
-	    ok;
-	Error ->
-	    Error
+read(Fd, Size) ->
+    try
+        #{ handle := FRef,
+           r_ahead_size := RASz,
+           r_buffer := RBuf } = get_fd_data(Fd),
+        read_1(FRef, RBuf, prim_buffer:size(RBuf), RASz, Size)
+    catch
+        error:badarg -> {error, badarg}
     end.
 
-%% Returns ok | {error, {WrittenCount, Reason}}
-pwrite(#file_descriptor{module = ?MODULE, data = {Port, _}}, L)
-  when is_list(L) ->
-    pwrite_int(Port, L, 0, [], []).
-
-pwrite_int(_, [], 0, [], []) ->
-    ok;
-pwrite_int(Port, [], N, Spec, Data) ->
-    Header = list_to_binary([?FILE_PWRITEV, erlang:dt_prepend_vm_tag_data(<<N:32>>) | reverse(Spec)]),
-    case drv_command_nt(Port, [Header | reverse(Data)], undefined) of
-	{ok, _Size} ->
-	    ok;
-	Error ->
-	    Error
-    end;
-pwrite_int(Port, [{Offs, Bytes} | T], N, Spec, Data)
-  when is_integer(Offs) ->
-    if
-	-(?LARGEFILESIZE) =< Offs, Offs < ?LARGEFILESIZE ->
-	    pwrite_int(Port, T, N, Spec, Data, Offs, Bytes);
-	true ->
-	    {error, einval}
+-spec read_1(FRef, RBuf, RBufSz, RASz, RSz) -> Result when
+      FRef :: prim_file_ref(),
+      RBuf :: term(),
+      RBufSz :: non_neg_integer(),
+      RASz :: non_neg_integer(),
+      RSz :: non_neg_integer(),
+      Result :: eof | {ok, binary()} | {error, Reason :: atom()}.
+read_1(_FRef, RBuf, RBufSz, _RASz, RSz) when RBufSz >= RSz ->
+    {ok, prim_buffer:read(RBuf, RSz)};
+read_1(FRef, RBuf, RBufSz, RASz, RSz) when RBufSz > 0 ->
+    Buffered = prim_buffer:read(RBuf, RBufSz),
+    case read_1(FRef, RBuf, 0, RASz, RSz - RBufSz) of
+        {ok, Data} ->
+            {ok, <<Buffered/binary, Data/binary>>};
+        eof ->
+            {ok, Buffered};
+        {error, Reason} ->
+            {error, Reason}
     end;
-pwrite_int(_, [_|_], _N, _Spec, _Data) ->
-    {error, badarg}.
+read_1(FRef, RBuf, RBufSz, RASz, RSz) when RBufSz =:= 0 ->
+    case read_nif(FRef, RASz + RSz) of
+        {ok, Data} when byte_size(Data) > RSz ->
+            {First, Rest} = split_binary(Data, RSz),
+            prim_buffer:write(RBuf, [Rest]),
+            {ok, First};
+        {ok, Data} when byte_size(Data) =< RSz ->
+            {ok, Data};
+        eof ->
+            eof;
+        {error, Reason} ->
+            {error, Reason}
+    end.
 
-pwrite_int(Port, T, N, Spec, Data, Offs, Bin)
-  when is_binary(Bin) ->
-    Size = byte_size(Bin),
-    pwrite_int(Port, T, N+1, 
-	       [<<Offs:64/signed, Size:64>> | Spec], 
-	       [Bin | Data]);
-pwrite_int(Port, T, N, Spec, Data, Offs, Bytes) ->
-    try list_to_binary(Bytes) of
-	Bin ->
-	    pwrite_int(Port, T, N, Spec, Data, Offs, Bin)
+read_line(Fd) ->
+    try
+        #{ handle := FRef,
+           r_ahead_size := RASz,
+           r_buffer := RBuf } = get_fd_data(Fd),
+        SearchResult = prim_buffer:find_byte_index(RBuf, $\n),
+        LineSize = max(?MIN_READLINE_SIZE, RASz),
+        read_line_1(FRef, RBuf, SearchResult, LineSize)
     catch
-	error:Reason ->
-	    {error, Reason}
+        error:badarg -> {error, badarg}
     end.
 
-
-
-%% Returns {error, Reason} | ok.
-pwrite(#file_descriptor{module = ?MODULE, data = {Port, _}}, Offs, Bytes) 
-  when is_integer(Offs) ->
-    if
-	-(?LARGEFILESIZE) =< Offs, Offs < ?LARGEFILESIZE ->
-	    case pwrite_int(Port, [], 0, [], [], Offs, Bytes) of
-		{error, {_, Reason}} ->
-		    {error, Reason};
-		Result ->
-		    Result
-	    end;
-	true ->
-	    {error, einval}
+-spec read_line_1(FRef, RBuf, SearchResult, LineSize) -> Result when
+      FRef :: prim_file_ref(),
+      RBuf :: term(),
+      SearchResult :: not_found | {ok, non_neg_integer()},
+      LineSize :: non_neg_integer(),
+      Result :: eof | {ok, binary()} | {error, Reason :: atom()}.
+read_line_1(FRef, RBuf, not_found, LineSize) ->
+    case read_nif(FRef, LineSize) of
+        {ok, Data} ->
+            prim_buffer:write(RBuf, [Data]),
+            SearchResult = prim_buffer:find_byte_index(RBuf, $\n),
+            read_line_1(FRef, RBuf, SearchResult, LineSize);
+        eof ->
+            case prim_buffer:size(RBuf) of
+                Size when Size > 0 -> {ok, prim_buffer:read(RBuf, Size)};
+                Size when Size =:= 0 -> eof
+            end;
+        {error, Reason} ->
+            {error, Reason}
     end;
-pwrite(#file_descriptor{module = ?MODULE}, _, _) ->
-    {error, badarg}.
-
+read_line_1(_FRef, RBuf, {ok, LFIndex}, _LineSize) ->
+    %% Translate CRLF into just LF, completely ignoring which encoding is used.
+    CRIndex = (LFIndex - 1),
+    case prim_buffer:read(RBuf, LFIndex + 1) of
+        <<Line:CRIndex/binary, "\r\n">> -> {ok, <<Line/binary, "\n">>};
+        Line -> {ok, Line}
+    end.
 
-%% Returns {error, Reason} | ok.
-datasync(#file_descriptor{module = ?MODULE, data = {Port, _}}) ->
-    drv_command(Port, [?FILE_FDATASYNC]).
-
-%% Returns {error, Reason} | ok.
-sync(#file_descriptor{module = ?MODULE, data = {Port, _}}) ->
-    drv_command(Port, [?FILE_FSYNC]).
-
-%% Returns {ok, Data} | eof | {error, Reason}.
-read_line(#file_descriptor{module = ?MODULE, data = {Port, _}}) ->
-    case drv_command(Port, <<?FILE_READ_LINE>>) of
-	{ok, {0, _Data}} ->
-	    eof;
-	{ok, {_Size, Data}} ->
-	    {ok, Data};
-	{error, enomem} ->
-	    erlang:garbage_collect(),
-	    case drv_command(Port, <<?FILE_READ_LINE>>) of
-		{ok, {0, _Data}} ->
-		    eof;
-		{ok, {_Size, Data}} ->
-		    {ok, Data};
-		Other ->
-		    Other
-	    end;
-	Error ->
-	    Error
+write(Fd, IOData) ->
+    try
+        #{ handle := FRef } = get_fd_data(Fd),
+        reset_write_position(Fd),
+        write_1(FRef, erlang:iolist_to_iovec(IOData))
+    catch
+        error:badarg -> {error, badarg}
     end.
-	
-%% Returns {ok, Data} | eof | {error, Reason}.
-read(#file_descriptor{module = ?MODULE, data = {Port, _}}, Size)
-  when is_integer(Size), 0 =< Size ->
-    if
-	Size < ?LARGEFILESIZE ->
-	    case drv_command(Port, <<?FILE_READ, Size:64>>) of
-		{ok, {0, _Data}} when Size =/= 0 ->
-		    eof;
-		{ok, {_Size, Data}} ->
-		    {ok, Data};
-		{error, enomem} ->
-		    %% Garbage collecting here might help if
-		    %% the current processes have some old binaries left.
-		    erlang:garbage_collect(),
-		    case drv_command(Port, <<?FILE_READ, Size:64>>) of
-			{ok, {0, _Data}} when Size =/= 0 ->
-			    eof;
-			{ok, {_Size, Data}} ->
-			    {ok, Data};
-			Other ->
-			    Other
-		    end;
-		Error ->
-		    Error
-	    end;
-	true ->
-	    {error, einval}
+write_1(FRef, IOVec) ->
+    case write_nif(FRef, IOVec) of
+        {continue, Remainder} ->
+            write_1(FRef, Remainder);
+        ok ->
+            ok;
+        {error, Reason} ->
+            {error, Reason}
     end.
 
-%% Returns {ok, [Data|eof, ...]} | {error, Reason}
-pread(#file_descriptor{module = ?MODULE, data = {Port, _}}, L)
-  when is_list(L) ->
-    pread_int(Port, L, 0, []).
-
-pread_int(_, [], 0, []) ->
-    {ok, []};
-pread_int(Port, [], N, Spec) ->
-    drv_command_nt(Port, [?FILE_PREADV, erlang:dt_prepend_vm_tag_data(<<0:32, N:32>>) | reverse(Spec)],undefined);
-pread_int(Port, [{Offs, Size} | T], N, Spec)
-  when is_integer(Offs), is_integer(Size), 0 =< Size ->
-    if
-	-(?LARGEFILESIZE) =< Offs, Offs < ?LARGEFILESIZE,
-	Size < ?LARGEFILESIZE ->
-	    pread_int(Port, T, N+1, [<<Offs:64/signed, Size:64>> | Spec]);
-	true ->
-	    {error, einval}
-    end;
-pread_int(_, [_|_], _N, _Spec) ->
-    {error, badarg}.
-
-
-
-%% Returns {ok, Data} | eof | {error, Reason}.
-pread(#file_descriptor{module = ?MODULE, data = {Port, _}}, Offs, Size) 
-  when is_integer(Offs), is_integer(Size), 0 =< Size ->
-    if
-	-(?LARGEFILESIZE) =< Offs, Offs < ?LARGEFILESIZE,
-	Size < ?LARGEFILESIZE ->
-	    case drv_command_nt(Port, 
-				[?FILE_PREADV, erlang:dt_prepend_vm_tag_data(<<0:32, 1:32,
-									     Offs:64/signed, Size:64>>)], undefined) of
-		{ok, [eof]} ->
-		    eof;
-		{ok, [Data]} ->
-		    {ok, Data};
-		Error ->
-		    Error
-	    end;
-	true ->
-	    {error, einval}
-    end;
-pread(#file_descriptor{module = ?MODULE, data = {_, _}}, _, _) ->
-    {error, badarg}.
-
-
-
-%% Returns {ok, Position} | {error, Reason}.
-position(#file_descriptor{module = ?MODULE, data = {Port, _}}, At) ->
-    case lseek_position(At) of
-	{Offs, Whence}
-	when -(?LARGEFILESIZE) =< Offs, Offs < ?LARGEFILESIZE ->
-	    drv_command(Port, <<?FILE_LSEEK, Offs:64/signed, Whence:32>>);
-	{_, _} ->
-	    {error, einval};
-	Reason ->
-	    {error, Reason}
+truncate(Fd) ->
+    try
+        #{ handle := FRef } = get_fd_data(Fd),
+        reset_write_position(Fd),
+        truncate_nif(FRef)
+    catch
+        error:badarg -> {error, badarg}
     end.
 
-%% Returns {error, Reason} | ok.
-truncate(#file_descriptor{module = ?MODULE, data = {Port, _}}) ->
-    drv_command(Port, <<?FILE_TRUNCATE>>).
-
-
-
-%% Returns {error, Reason} | {ok, BytesCopied}
-copy(#file_descriptor{module = ?MODULE} = Source,
-     #file_descriptor{module = ?MODULE} = Dest,
-     Length)
-  when is_integer(Length), Length >= 0;
-       is_atom(Length) ->
-    %% XXX Should be moved down to the driver for optimization.
-    file:copy_opened(Source, Dest, Length).
-
-
-
-ipread_s32bu_p32bu(#file_descriptor{module = ?MODULE,
-				    data = {_, _}} = Handle,
-		   Offs,
-		   Infinity) when is_atom(Infinity) ->
-    ipread_s32bu_p32bu(Handle, Offs, (1 bsl 31)-1);
-ipread_s32bu_p32bu(#file_descriptor{module = ?MODULE, data = {Port, _}},
-		   Offs,
-		   MaxSize)
-  when is_integer(Offs), is_integer(MaxSize) ->
-    if
-	-(?LARGEFILESIZE) =< Offs, Offs < ?LARGEFILESIZE,
-	0 =< MaxSize, MaxSize < (1 bsl 31) ->
-	    drv_command(Port, <<?FILE_IPREAD, ?IPREAD_S32BU_P32BU,
-			       Offs:64, MaxSize:32>>);
-	true ->
-	    {error, einval}
-    end;
-ipread_s32bu_p32bu(#file_descriptor{module = ?MODULE, data = {_, _}},
-		   _Offs,
-		   _MaxSize) ->
-    {error, badarg}.
+advise(Fd, Offset, Length, Advise) ->
+    try
+        #{ handle := FRef } = get_fd_data(Fd),
+        advise_nif(FRef, Offset, Length, Advise)
+    catch
+        error:badarg -> {error, badarg}
+    end.
 
+allocate(Fd, Offset, Length) ->
+    try
+        #{ handle := FRef } = get_fd_data(Fd),
+        allocate_nif(FRef, Offset, Length)
+    catch
+        error:badarg -> {error, badarg}
+    end.
 
+sync(Fd) ->
+    try
+        #{ handle := FRef } = get_fd_data(Fd),
+        sync_nif(FRef, 0)
+    catch
+        error:badarg -> {error, badarg}
+    end.
 
-%% Returns {ok, Contents} | {error, Reason}
-read_file(File) when (is_list(File) orelse is_binary(File)) ->
-    case drv_open(?FD_DRV, [binary]) of
-	{ok, Port} ->
-	    Result = read_file(Port, File),
-	    close(Port),
-	    Result;
-	{error, _} = Error ->
-	    Error
-    end;
-read_file(_) ->
-    {error, badarg}.
+datasync(Fd) ->
+    try
+        #{ handle := FRef } = get_fd_data(Fd),
+        sync_nif(FRef, 1)
+    catch
+        error:badarg -> {error, badarg}
+    end.
 
-%% Takes a Port opened with open/1.
-read_file(Port, File) when is_port(Port),
-			   (is_list(File) orelse is_binary(File)) ->
-    Cmd = [?FILE_READ_FILE | pathname(File)],
-    case drv_command(Port, Cmd) of
-	{error, enomem} ->
-	    %% It could possibly help to do a 
-	    %% garbage collection here, 
-	    %% if the file server has some references
-	    %% to binaries read earlier.
-	    erlang:garbage_collect(),
-	    drv_command(Port, Cmd);
-	Result ->
-	    Result
+position(Fd, {cur, Offset}) ->
+    try
+        %% Adjust our current position according to how much we've read ahead.
+        #{ r_buffer := RBuf } = get_fd_data(Fd),
+        position_1(Fd, cur, Offset - prim_buffer:size(RBuf))
+    catch
+        error:badarg -> {error, badarg}
     end;
-read_file(_,_) ->
-    {error, badarg}.
-
-    
-
-%% Returns {error, Reason} | ok.
-write_file(File, Bin) when (is_list(File) orelse is_binary(File)) ->
-    case open(File, [binary, write]) of
-	{ok, Handle} ->
-	    Result = write(Handle, Bin),
-	    close(Handle),
-	    Result;
-	Error ->
-	    Error
+position(Fd, {Mark, Offset}) ->
+    try
+        position_1(Fd, Mark, Offset)
+    catch
+        error:badarg -> {error, badarg}
     end;
-write_file(_, _) -> 
-    {error, badarg}.
+position(Fd, cur) -> position(Fd, {cur, 0});
+position(Fd, bof) -> position(Fd, {bof, 0});
+position(Fd, eof) -> position(Fd, {eof, 0});
+position(Fd, Offset) -> position(Fd, {bof, Offset}).
 
+position_1(Fd, Mark, Offset) ->
+    #{ handle := FRef, r_buffer := RBuf } = get_fd_data(Fd),
+    prim_buffer:wipe(RBuf),
+    seek_nif(FRef, Mark, Offset).
 
-%% Returns {error, Reason} | {ok, BytesCopied}
-%sendfile(_,_,_,_,_,_,_,_,_,_) ->
-%    {error, enotsup};
-sendfile(#file_descriptor{module = ?MODULE, data = {Port, _}},
-	 Dest, Offset, Bytes, _ChunkSize, Headers, Trailers,
-	 Flags) ->
-    case erlang:port_get_data(Dest) of
-	Data when Data == inet_tcp; Data == inet6_tcp ->
-	    ok = inet:lock_socket(Dest,true),
-	    {ok, DestFD} = prim_inet:getfd(Dest),
-	    IntFlags = translate_sendfile_flags(Flags),
-	    try drv_command(Port, [<<?FILE_SENDFILE, DestFD:32,
-				     IntFlags:8,
-				     Offset:64/unsigned,
-				     Bytes:64/unsigned,
-				     (iolist_size(Headers)):32/unsigned,
-				     (iolist_size(Trailers)):32/unsigned>>,
-				   Headers,Trailers])
-	    after
-		ok = inet:lock_socket(Dest,false)
-	    end;
-	_Else ->
-	    {error,badarg}
+pread(Fd, Offset, Size) ->
+    try
+        #{ handle := FRef } = get_fd_data(Fd),
+        pread_nif(FRef, Offset, Size)
+    catch
+        error:badarg -> {error, badarg}
     end.
 
-translate_sendfile_flags([{use_threads,true}|T]) ->
-    ?EFILE_SENDFILE_USE_THREADS bor translate_sendfile_flags(T);
-translate_sendfile_flags([_|T]) ->
-    translate_sendfile_flags(T);
-translate_sendfile_flags([]) ->
-    0.
-
-
-%%%-----------------------------------------------------------------
-%%% Functions operating on files without handle to the file. ?DRV.
-%%%
-%%% Supposed to be called by applications through module file.
-
-
-
-%% Returns {ok, Port}, the Port should be used as first argument in all
-%% the following functions. Returns {error, Reason} upon failure.
-start() ->
-    drv_open(?DRV, [binary]).
-
-stop(Port) when is_port(Port) ->
-    try erlang:port_close(Port) of
-	_ ->
-	    ok
+pread(Fd, LocNums) ->
+    try
+        #{ handle := FRef } = get_fd_data(Fd),
+        pread_list(FRef, LocNums, [])
     catch
-	_:_ ->
-	    ok
+        error:badarg -> {error, badarg}
     end.
 
+-spec pread_list(FRef, LocNums, ResultList) -> Result when
+      FRef :: prim_file_ref(),
+      LocNums :: list({Offset :: non_neg_integer(),
+                       Size :: non_neg_integer()}),
+      ResultList :: list(eof | binary()),
+      Result :: {ok, ResultList} | {error, Reason :: atom()}.
+pread_list(_FRef, [], ResultList) ->
+    {ok, reverse_list(ResultList)};
+pread_list(FRef, [{Offset, Size} | Rest], ResultList) ->
+    case pread_nif(FRef, Offset, Size) of
+        {ok, Data} ->
+            pread_list(FRef, Rest, [Data | ResultList]);
+        eof ->
+            pread_list(FRef, Rest, [eof | ResultList]);
+        {error, Reason} ->
+            {error, Reason}
+    end.
 
+pwrite(Fd, Offset, IOData) ->
+    try
+        #{ handle := FRef, r_buffer := RBuf } = get_fd_data(Fd),
+        prim_buffer:wipe(RBuf),
+        pwrite_plain(FRef, Offset, erlang:iolist_to_iovec(IOData))
+    catch
+        error:badarg -> {error, badarg}
+    end.
+pwrite_plain(FRef, Offset, IOVec) ->
+    case pwrite_nif(FRef, Offset, IOVec) of
+        {continue, BytesWritten, Remainder} ->
+            pwrite_plain(FRef, Offset + BytesWritten, Remainder);
+        ok ->
+            ok;
+        {error, Reason} ->
+            {error, Reason}
+    end.
 
-%%% The following functions take an optional Port as first argument.
-%%% If the port is not supplied, a temporary one is opened and then
-%%% closed after the request has been performed.
-
-
-
-%% get_cwd/{0,1,2}
-
-get_cwd() ->
-    get_cwd_int(0).
-
-get_cwd(Port) when is_port(Port) ->
-    get_cwd_int(Port, 0);
-get_cwd([]) ->
-    get_cwd_int(0);
-get_cwd([Letter, $: | _]) when $a =< Letter, Letter =< $z ->
-    get_cwd_int(Letter - $a + 1);
-get_cwd([Letter, $: | _]) when $A =< Letter, Letter =< $Z ->
-    get_cwd_int(Letter - $A + 1);
-get_cwd([_|_]) ->
-    {error, einval};
-get_cwd(_) ->
-    {error, badarg}.
-
-get_cwd(Port, []) when is_port(Port) ->
-    get_cwd_int(Port, 0);
-get_cwd(Port, [Letter, $: | _])
-  when is_port(Port), $a =< Letter, Letter =< $z ->
-    get_cwd_int(Port, Letter - $a + 1);
-get_cwd(Port, [Letter, $: | _])
-  when is_port(Port), $A =< Letter, Letter =< $Z ->
-    get_cwd_int(Port, Letter - $A + 1);
-get_cwd(Port, [_|_]) when is_port(Port) ->
-    {error, einval};
-get_cwd(_, _) ->
-    {error, badarg}.
-
-get_cwd_int(Drive) ->
-    get_cwd_int({?DRV, [binary]}, Drive).
-
-get_cwd_int(Port, Drive) ->
-    drv_command(Port, <<?FILE_PWD, Drive>>,
-		fun handle_fname_response/1).
-
-
-
-%% set_cwd/{1,2}
+pwrite(Fd, LocBytes) ->
+    try
+        #{ handle := FRef, r_buffer := RBuf } = get_fd_data(Fd),
+        prim_buffer:wipe(RBuf),
+        pwrite_list(FRef, LocBytes, 0)
+    catch
+        error:badarg -> {error, badarg}
+    end.
 
-set_cwd(Dir) ->
-    set_cwd_int({?DRV, [binary]}, Dir).
+-spec pwrite_list(FRef, LocBytes, Successes) -> Result when
+      FRef :: prim_file_ref(),
+      LocBytes :: list({Offset :: non_neg_integer(),
+                        IOData :: iodata()}),
+      Successes :: non_neg_integer(),
+      Result :: ok | {error, {Successes, Reason :: atom()}}.
+pwrite_list(_FRef, [], _Successes) ->
+    ok;
+pwrite_list(FRef, [{Offset, IOData} | Rest], Successes) ->
+    case pwrite_plain(FRef, Offset, erlang:iolist_to_iovec(IOData)) of
+        {error, Reason} -> {error, {Successes, Reason}};
+        ok -> pwrite_list(FRef, Rest, Successes + 1)
+    end.
 
-set_cwd(Port, Dir) when is_port(Port) ->
-    set_cwd_int(Port, Dir).
+sendfile(Fd, Socket, Offset, Bytes, _ChunkSize, [], [], _Flags) ->
+    %% There's a very nasty race in here; if we die just prior to duplicating
+    %% the handle down in the sendfile call, it might get reused by something
+    %% entirely different and we'll leak unknown data to the socket until it
+    %% dies soon after.
+    %%
+    %% This bug was inherited from the old driver, except it was vulnerable to
+    %% the bug at any point and not just during setup.
+    %%
+    %% We'll have to live with this until we have a way to unambiguously
+    %% transfer things between drivers or NIFs. Current ideas all fall afoul
+    %% of the Two Generals problem.
+    try
+        advise(Fd, Offset, Bytes, sequential),
+        prim_inet:sendfile(Socket, get_handle(Fd), Offset, Bytes)
+    catch
+        error:badarg -> {error, badarg}
+    end;
+sendfile(_Fd, _Socket, _Offset, _Bytes, _ChunkSize, _Headers, _Trailers, _Flags) ->
+    {error, enotsup}.
 
-set_cwd_int(Port, Dir) when is_binary(Dir) ->
-    case prim_file:is_translatable(Dir) of
-	false ->
-	    {error, no_translation};
-	true ->
-	    drv_command(Port, [?FILE_CHDIR, pathname(Dir)])
+%% Undocumented internal function that reads a data block with indirection.
+%%
+%% This is only used once in DETS and can easily be emulated with pread/2, but
+%% it's pretty performance-sensitive so we've implemented it down in the NIF to
+%% avoid excessive rescheduling.
+-spec ipread_s32bu_p32bu(Fd, Offset, MaxSize) -> Result when
+      Fd :: #file_descriptor{},
+      Offset :: non_neg_integer(),
+      MaxSize :: non_neg_integer() | infinity,
+      Result :: {ok, Size :: non_neg_integer(),
+                     Pointer :: non_neg_integer(),
+                     Data :: iodata() | eof} |
+                eof |
+                {error, Reason :: atom()}.
+ipread_s32bu_p32bu(Fd, Offset, Infinity) when is_atom(Infinity) ->
+    ipread_s32bu_p32bu(Fd, Offset, (1 bsl 31) - 1);
+ipread_s32bu_p32bu(Fd, Offset, MaxSize)
+        when is_integer(Offset), is_integer(MaxSize) ->
+    try
+        #{ handle := FRef } = get_fd_data(Fd),
+        ipread_s32bu_p32bu_nif(FRef, Offset, MaxSize)
+    catch
+        error:badarg -> {error, badarg}
     end;
-set_cwd_int(Port, Dir) when is_list(Dir) ->
-    drv_command(Port, [?FILE_CHDIR, pathname(Dir)]);
-set_cwd_int(_, _) ->
+ipread_s32bu_p32bu(_Fd, _Offset, _MaxSize) ->
     {error, badarg}.
-
-
-
-%% delete/{1,2}
-
-delete(File) ->
-    delete_int({?DRV, [binary]}, File).
-
-delete(Port, File) when is_port(Port) ->
-    delete_int(Port, File).
-
-delete_int(Port, File) ->
-    drv_command(Port, [?FILE_DELETE, pathname(File)]).
-
-
-
-%% rename/{2,3}
-
-rename(From, To) ->
-    rename_int({?DRV, [binary]}, From, To).
-
-rename(Port, From, To) when is_port(Port) ->
-    rename_int(Port, From, To).
-
-rename_int(Port, From, To) ->
-    drv_command(Port, [?FILE_RENAME, pathname(From), pathname(To)]).
-
-
-
-%% make_dir/{1,2}
-
-make_dir(Dir) ->
-    make_dir_int({?DRV, [binary]}, Dir).
-
-make_dir(Port, Dir) when is_port(Port) ->
-    make_dir_int(Port, Dir).
-
-make_dir_int(Port, Dir) ->
-    drv_command(Port, [?FILE_MKDIR, pathname(Dir)]).
-
-
-
-%% del_dir/{1,2}
-
-del_dir(Dir) ->
-    del_dir_int({?DRV, [binary]}, Dir).
-
-del_dir(Port, Dir) when is_port(Port) ->
-    del_dir_int(Port, Dir).
-
-del_dir_int(Port, Dir) ->
-    drv_command(Port, [?FILE_RMDIR, pathname(Dir)]).
-
-
-
-%% read_file_info/{1,2,3}
-
-read_file_info(File) ->
-    read_file_info_int({?DRV, [binary]}, File, local).
-
-read_file_info(Port, File) when is_port(Port) ->
-    read_file_info_int(Port, File, local);
-read_file_info(File, Opts) ->
-    read_file_info_int({?DRV, [binary]}, File, plgv(time, Opts, local)).
-
-read_file_info(Port, File, Opts) when is_port(Port) ->
-    read_file_info_int(Port, File, plgv(time, Opts, local)).
-
-read_file_info_int(Port, File, TimeType) ->
+ipread_s32bu_p32bu_nif(_FRef, _Offset, _MaxSize) ->
+    erlang:nif_error(undef).
+
+%% Returns the binary representation of the underlying handle, for use in
+%% tricky operations like sendfile/8.
+-spec get_handle(Fd) -> Result when
+      Fd :: #file_descriptor{},
+      Result :: binary() | {error, Reason :: atom()}.
+get_handle(Fd) ->
     try
-	case drv_command(Port, [?FILE_FSTAT, pathname(File)]) of
-	    {ok, FI} -> {ok, FI#file_info{
-			ctime = from_seconds(FI#file_info.ctime, TimeType),
-			mtime = from_seconds(FI#file_info.mtime, TimeType),
-			atime = from_seconds(FI#file_info.atime, TimeType)
-		    }};
-	    Error    -> Error
-	end
+        #{ handle := FRef } = get_fd_data(Fd),
+        get_handle_nif(FRef)
     catch
-	error:_ -> {error, badarg}
+        error:badarg -> {error, badarg}
     end.
 
+%% Resets the write head to the position the user believes we're at, which may
+%% not be the same as the real one when read caching is in effect.
+reset_write_position(Fd) ->
+    #{ r_buffer := RBuf } = Fd#file_descriptor.data,
+    case prim_buffer:size(RBuf) of
+        Size when Size > 0 -> position(Fd, cur);
+        Size when Size =:= 0 -> ok
+    end.
 
-%% altname/{1,2}
-
-altname(File) ->
-    altname_int({?DRV, [binary]}, File).
-
-altname(Port, File) when is_port(Port) ->
-    altname_int(Port, File).
-
-altname_int(Port, File) ->
-    drv_command(Port, [?FILE_ALTNAME, pathname(File)],
-		fun handle_fname_response/1).
-
-%% write_file_info/{2,3,4}
-
-write_file_info(File, Info) ->
-    write_file_info_int({?DRV, [binary]}, File, Info, local).
-
-write_file_info(Port, File, Info) when is_port(Port) ->
-    write_file_info_int(Port, File, Info, local);
-write_file_info(File, Info, Opts) ->
-    write_file_info_int({?DRV, [binary]}, File, Info, plgv(time, Opts, local)).
-
-write_file_info(Port, File, Info, Opts) when is_port(Port) ->
-    write_file_info_int(Port, File, Info, plgv(time, Opts, local)).
+get_fd_data(#file_descriptor{ data = Data }) ->
+    #{ owner := Owner } = Data,
+    case self() of
+        Owner -> Data;
+        _ -> error(not_on_controlling_process)
+    end.
 
-write_file_info_int(Port, File, 
-		    #file_info{mode=Mode, 
-			       uid=Uid, 
-			       gid=Gid,
-			       atime=Atime0, 
-			       mtime=Mtime0, 
-			       ctime=Ctime0},
-		       TimeType) ->
+build_fd_data(FRef, Modes) ->
+    Defaults =
+        #{ owner => self(),
+           handle => FRef,
+           r_ahead_size => 0,
+           r_buffer => prim_buffer:new() },
+    fill_fd_option_map(Modes, Defaults).
+
+fill_fd_option_map([], Map) ->
+    Map;
+
+fill_fd_option_map([read_ahead | Modes], Map) ->
+    fill_fd_option_map([{read_ahead, 64 bsl 10} | Modes], Map);
+fill_fd_option_map([{read_ahead, Size} | Modes], Map) ->
+    fill_fd_option_map(Modes, Map#{ r_ahead_size => Size });
+
+fill_fd_option_map([_Ignored | Modes], Map) ->
+    fill_fd_option_map(Modes, Map).
+
+open_nif(_Name, _Modes) ->
+    erlang:nif_error(undef).
+close_nif(_FileRef) ->
+    erlang:nif_error(undef).
+read_nif(_FileRef, _Size) ->
+    erlang:nif_error(undef).
+write_nif(_FileRef, _IOVec) ->
+    erlang:nif_error(undef).
+pread_nif(_FileRef, _Offset, _Size) ->
+    erlang:nif_error(undef).
+pwrite_nif(_FileRef, _Offset, _IOVec) ->
+    erlang:nif_error(undef).
+seek_nif(_FileRef, _Mark, _Offset) ->
+    erlang:nif_error(undef).
+sync_nif(_FileRef, _DataOnly) ->
+    erlang:nif_error(undef).
+advise_nif(_FileRef, _Offset, _Length, _Advise) ->
+    erlang:nif_error(undef).
+allocate_nif(_FileRef, _Offset, _Length) ->
+    erlang:nif_error(undef).
+truncate_nif(_FileRef) ->
+    erlang:nif_error(undef).
+get_handle_nif(_FileRef) ->
+    erlang:nif_error(undef).
 
-    % Atime and/or Mtime might be undefined
-    %  - use localtime() for atime, if atime is undefined
-    %  - use atime as mtime if mtime is undefined
-    %  - use mtime as ctime if ctime is undefined
+%%
+%% Quality-of-life helpers
+%%
 
+read_file(Filename) ->
+    %% We're doing this operation in the NIF to avoid excessive rescheduling.
     try
-	Atime = file_info_validate_atime(Atime0, TimeType),
-	Mtime = file_info_validate_mtime(Mtime0, Atime),
-	Ctime = file_info_validate_ctime(Ctime0, Mtime),
-
-	drv_command(Port, [?FILE_WRITE_INFO, 
-		int_to_int32bytes(Mode), 
-		int_to_int32bytes(Uid), 
-		int_to_int32bytes(Gid),
-		int_to_int64bytes(to_seconds(Atime, TimeType)), 
-		int_to_int64bytes(to_seconds(Mtime, TimeType)), 
-		int_to_int64bytes(to_seconds(Ctime, TimeType)),
-		pathname(File)])
+        read_file_nif(encode_path(Filename))
     catch
-	error:_ -> {error, badarg}
+        error:badarg -> {error, badarg}
+    end.
+read_file_nif(_Filename) ->
+    erlang:nif_error(undef).
+
+write_file(Filename, Bytes) ->
+    write_file(Filename, Bytes, []).
+write_file(Filename, Bytes, Modes) ->
+    case open(Filename, [write, binary | Modes]) of
+        {ok, Fd} ->
+            Result = write(Fd, Bytes),
+            close(Fd),
+            Result;
+        {error, Reason} ->
+            {error, Reason}
     end.
 
+%%
+%% Filesystem operations
+%%
 
-file_info_validate_atime(Atime, _) when Atime =/= undefined -> Atime;
-file_info_validate_atime(undefined, local)     -> erlang:localtime();
-file_info_validate_atime(undefined, universal) -> erlang:universaltime();
-file_info_validate_atime(undefined, posix)     -> erlang:universaltime_to_posixtime(erlang:universaltime()).
-
-file_info_validate_mtime(undefined, Atime) -> Atime;
-file_info_validate_mtime(Mtime, _)         -> Mtime.
-
-file_info_validate_ctime(undefined, Mtime) -> Mtime;
-file_info_validate_ctime(Ctime, _)         -> Ctime.
-
-%% make_link/{2,3}
-
-make_link(Old, New) ->
-    make_link_int({?DRV, [binary]}, Old, New).
-
-make_link(Port, Old, New) when is_port(Port) ->
-    make_link_int(Port, Old, New).
-
-make_link_int(Port, Old, New) ->
-    drv_command(Port, [?FILE_LINK, pathname(Old), pathname(New)]).
-
-
-
-%% make_symlink/{2,3}
-
-make_symlink(Old, New) ->
-    make_symlink_int({?DRV, [binary]}, Old, New).
-
-make_symlink(Port, Old, New) when is_port(Port) ->
-    make_symlink_int(Port, Old, New).
-
-make_symlink_int(Port, Old, New) ->
-    drv_command(Port, [?FILE_SYMLINK, pathname(Old), pathname(New)]).
-
-
-
-%% read_link/{2,3}
-
-read_link(Link) ->
-    read_link_int({?DRV, [binary]}, Link).
-
-read_link(Port, Link) when is_port(Port) ->
-    read_link_int(Port, Link).
-
-read_link_int(Port, Link) ->
-    drv_command(Port, [?FILE_READLINK, pathname(Link)],
-		fun handle_fname_response/1).
-
-%% read_link_all/{2,3}
-
-read_link_all(Link) ->
-    read_link_all_int({?DRV, [binary]}, Link).
-
-read_link_all(Port, Link) when is_port(Port) ->
-    read_link_all_int(Port, Link).
-
-read_link_all_int(Port, Link) ->
-    drv_command(Port, [?FILE_READLINK, pathname(Link)],
-		fun handle_fname_response_all/1).
-
-
-
-%% read_link_info/{2,3}
-
-read_link_info(Link) ->
-    read_link_info_int({?DRV, [binary]}, Link, local).
-
-read_link_info(Port, Link) when is_port(Port) ->
-    read_link_info_int(Port, Link, local);
+read_link(Name) -> read_link_1(Name, false).
+read_link_all(Name) -> read_link_1(Name, true).
 
-read_link_info(Link, Opts) ->
-    read_link_info_int({?DRV, [binary]}, Link, plgv(time, Opts, local)).
+read_link_1(Name, AcceptRawNames) ->
+    try read_link_nif(encode_path(Name)) of
+        {ok, RawName} -> translate_raw_name(RawName, AcceptRawNames);
+        {error, Reason} -> {error, Reason}
+    catch
+        error:badarg -> {error, badarg}
+    end.
 
-read_link_info(Port, Link, Opts) when is_port(Port) ->
-    read_link_info_int(Port, Link, plgv(time, Opts, local)).
+translate_raw_name(RawName, SilentFailure) ->
+    case decode_path(RawName) of
+        Converted when is_list(Converted) -> {ok, Converted};
+        {error, _Reason} when SilentFailure =:= false -> {error, einval};
+        {error, _Reason} when SilentFailure =:= true -> {ok, RawName}
+    end.
 
+list_dir(Name) -> list_dir_1(Name, true).
+list_dir_all(Name) -> list_dir_1(Name, false).
 
-read_link_info_int(Port, Link, TimeType) ->
-    try
-	case drv_command(Port, [?FILE_LSTAT, pathname(Link)]) of
-	    {ok, FI} -> {ok, FI#file_info{
-			ctime = from_seconds(FI#file_info.ctime, TimeType),
-			mtime = from_seconds(FI#file_info.mtime, TimeType),
-			atime = from_seconds(FI#file_info.atime, TimeType)
-		    }};
-	    Error    -> Error
-	end
+list_dir_1(Name, SkipInvalid) ->
+    try list_dir_nif(encode_path(Name)) of
+        {ok, RawNames} -> list_dir_convert(RawNames, SkipInvalid, []);
+        {error, Reason} -> {error, Reason}
     catch
-	error:_ -> {error, badarg}
+        error:badarg -> {error, badarg}
     end.
 
-%% list_dir/{1,2}
-
-list_dir(Dir) ->
-    list_dir_int({?DRV, [binary]}, Dir).
-
-list_dir(Port, Dir) when is_port(Port) ->
-    list_dir_int(Port, Dir).
-
-list_dir_int(Port, Dir) ->
-    drv_command(Port, [?FILE_READDIR, pathname(Dir)],
-		fun(P) ->
-			case list_dir_response(P, []) of
-			    {ok, RawNames} ->
-				try
-				    {ok, list_dir_convert(RawNames)}
-				catch
-				    throw:Reason ->
-					Reason
-				end;
-			    Error ->
-				Error
-			end
-		end).
-
-list_dir_all(Dir) ->
-    list_dir_all_int({?DRV, [binary]}, Dir).
-
-list_dir_all(Port, Dir) when is_port(Port) ->
-    list_dir_all_int(Port, Dir).
-
-list_dir_all_int(Port, Dir) ->
-    drv_command(Port, [?FILE_READDIR, pathname(Dir)],
-		fun(P) ->
-			case list_dir_response(P, []) of
-			    {ok, RawNames} ->
-				{ok, list_dir_convert_all(RawNames)};
-			    Error ->
-				Error
-			end
-		end).
-
-list_dir_response(Port, Acc0) ->
-    case drv_get_response(Port) of
-	{lfname, []} ->
-	    {ok, Acc0};
-	{lfname, Names} ->
-	    Acc = [Name || <<L:16,Name:L/binary>> <= Names] ++ Acc0,
-	    list_dir_response(Port, Acc);
-	Error ->
-	    Error
+list_dir_convert([], _SkipInvalid, Result) ->
+    {ok, Result};
+list_dir_convert([RawName | Rest], SkipInvalid, Result) ->
+    case decode_path(RawName) of
+        Converted when is_list(Converted) ->
+            list_dir_convert(Rest, SkipInvalid, [Converted | Result]);
+        {error, _} when SkipInvalid =:= false ->
+            list_dir_convert(Rest, SkipInvalid, [RawName | Result]);
+
+        %% If the filename cannot be converted, return error or ignore with
+        %% optional error logger warning depending on +fn{u|a}{i|e|w} emulator
+        %% switches.
+        {error, ignore} ->
+            list_dir_convert(Rest, SkipInvalid, Result);
+        {error, warning} ->
+            error_logger:warning_msg(
+                "Non-unicode filename ~p ignored\n", [RawName]),
+            list_dir_convert(Rest, SkipInvalid, Result);
+        {error, _} ->
+            {error, {no_translation, RawName}}
     end.
 
-list_dir_convert([Name|Names]) ->
-    %% If the filename cannot be converted, return error or ignore
-    %% with optional error logger warning, depending on +fn{u|a}{i|e|w}
-    %% emulator switches.
-    case prim_file:internal_native2name(Name) of
-	{error, warning} ->
-	    error_logger:warning_msg("Non-unicode filename ~p ignored\n",
-				     [Name]),
-	    list_dir_convert(Names);
-	{error, ignore} ->
-	    list_dir_convert(Names);
-	{error, error} ->
-	    throw({error, {no_translation, Name}});
-	Converted when is_list(Converted) ->
-	    [Converted|list_dir_convert(Names)]
-    end;
-list_dir_convert([]) -> [].
-
-list_dir_convert_all([Name|Names]) ->
-    %% If the filename cannot be converted, retain the filename as
-    %% a binary.
-    case prim_file:internal_native2name(Name) of
-	{error, _} ->
-	    [Name|list_dir_convert_all(Names)];
-	Converted when is_list(Converted) ->
-	    [Converted|list_dir_convert_all(Names)]
-    end;
-list_dir_convert_all([]) -> [].
-
-%%%-----------------------------------------------------------------
-%%% Functions to communicate with the driver
-
-handle_fname_response(Port) ->
-    case drv_get_response(Port) of
-	{fname, Name} ->
-	    case prim_file:internal_native2name(Name) of
-		{error, warning} ->
-		    error_logger:warning_msg("Non-unicode filename ~p "
-					     "ignored when reading link\n",
-					     [Name]),
-		    {error, einval};
-		{error, _} ->
-		    {error, einval};
-		Converted when is_list(Converted) ->
-		    {ok, Converted}
-	    end;
-	Error ->
-	    Error
+read_file_info(Filename) ->
+    read_info_1(Filename, 1, local).
+read_file_info(Filename, Opts) ->
+    read_info_1(Filename, 1, proplist_get_value(time, Opts, local)).
+
+read_link_info(Name) ->
+    read_info_1(Name, 0, local).
+read_link_info(Name, Opts) ->
+    read_info_1(Name, 0, proplist_get_value(time, Opts, local)).
+
+read_info_1(Name, FollowLinks, TimeType) ->
+    try read_info_nif(encode_path(Name), FollowLinks) of
+        {error, Reason} -> {error, Reason};
+        FileInfo ->
+            CTime = from_posix_seconds(FileInfo#file_info.ctime, TimeType),
+            MTime = from_posix_seconds(FileInfo#file_info.mtime, TimeType),
+            ATime = from_posix_seconds(FileInfo#file_info.atime, TimeType),
+            {ok, FileInfo#file_info{ ctime = CTime, mtime = MTime, atime = ATime }}
+    catch
+        error:badarg -> {error, badarg}
     end.
 
-handle_fname_response_all(Port) ->
-    case drv_get_response(Port) of
-	{fname, Name} ->
-	    case prim_file:internal_native2name(Name) of
-		{error, _} ->
-		    {ok, Name};
-		Converted when is_list(Converted) ->
-		    {ok, Converted}
-	    end;
-	Error ->
-	    Error
+write_file_info(Filename, Info) ->
+    write_file_info_1(Filename, Info, local).
+write_file_info(Filename, Info, Opts) ->
+    write_file_info_1(Filename, Info, proplist_get_value(time, Opts, local)).
+
+write_file_info_1(Filename, Info, TimeType) ->
+    #file_info{ mode = Modes,
+                uid = Uid,
+                gid = Gid,
+                atime = ATime0,
+                mtime = MTime0,
+                ctime = CTime0} = Info,
+    try
+        % ATime and/or MTime might be undefined
+        %  - use localtime() for atime, if atime is undefined
+        %  - use atime as mtime if mtime is undefined
+        %  - use mtime as ctime if ctime is undefined
+        ATime = file_info_convert_atime(ATime0, TimeType),
+        MTime = file_info_convert_mtime(MTime0, ATime, TimeType),
+        CTime = file_info_convert_ctime(CTime0, MTime, TimeType),
+        EncodedName = encode_path(Filename),
+
+        %% This is a bit ugly but we need to handle partial failures the same
+        %% way the old driver did.
+        throw_on_error(set_owner(EncodedName, Uid, Gid)),
+        throw_on_error(set_permissions(EncodedName, Modes)),
+        throw_on_error(set_time(EncodedName, ATime, MTime, CTime))
+    catch
+        throw:Reason -> {error, Reason};
+        error:_ -> {error, badarg}
     end.
 
-%% Opens a driver port and converts any problems into {error, emfile}.
-%% Returns {ok, Port} when successful.
+set_owner(_EncodedName, undefined, undefined) ->
+    ok;
+set_owner(EncodedName, Uid, Gid) ->
+    set_owner_nif(EncodedName, Uid, Gid).
+set_owner_nif(_Path, _Uid, _Gid) ->
+    erlang:nif_error(undef).
 
-drv_open(Driver, Portopts) ->
-    try erlang:open_port({spawn_driver, Driver}, Portopts) of
-	Port ->
-	    {ok, Port}
+set_permissions(_EncodedName, undefined) ->
+    ok;
+set_permissions(EncodedName, Permissions) ->
+    set_permissions_nif(EncodedName, Permissions).
+set_permissions_nif(_Path, _Permissions) ->
+    erlang:nif_error(undef).
+
+set_time(EncodedName, ATime, MTime, CTime) ->
+    set_time_nif(EncodedName, ATime, MTime, CTime).
+set_time_nif(_Path, _ATime, _MTime, _CTime) ->
+    erlang:nif_error(undef).
+
+throw_on_error(ok) -> ok;
+throw_on_error({error, enotsup}) -> ok;
+throw_on_error({error, Reason}) -> throw(Reason).
+
+file_info_convert_atime(ATime, TimeType) when ATime =/= undefined ->
+    to_posix_seconds(ATime, TimeType);
+file_info_convert_atime(undefined, local) ->
+    to_posix_seconds(erlang:localtime(), local);
+file_info_convert_atime(undefined, universal) ->
+    to_posix_seconds(erlang:universaltime(), universal);
+file_info_convert_atime(undefined, posix) ->
+    erlang:universaltime_to_posixtime(erlang:universaltime()).
+
+file_info_convert_mtime(undefined, ATime, _TimeType) ->
+    ATime;
+file_info_convert_mtime(MTime, _ATime, TimeType) ->
+    to_posix_seconds(MTime, TimeType).
+
+file_info_convert_ctime(undefined, MTime, _TimeType) ->
+    MTime;
+file_info_convert_ctime(CTime, _MTime, TimeType) ->
+    to_posix_seconds(CTime, TimeType).
+
+%% This is only relevant on Windows, so we assume that format to simplify the
+%% internals.
+get_cwd([Letter, $:]) when Letter >= $A, Letter =< $Z ->
+    get_dcwd(Letter - $A + 1);
+get_cwd([Letter, $:]) when Letter >= $a, Letter =< $z ->
+    get_dcwd(Letter - $a + 1);
+get_cwd([_|_]) ->
+    {error, einval};
+get_cwd(_) ->
+    {error, badarg}.
+get_dcwd(Index) ->
+    try get_device_cwd_nif(Index) of
+        {ok, RawPath} -> {ok, decode_path(RawPath)};
+        {error, Reason} -> {error, Reason}
     catch
-	error:Reason ->
-	    {error, Reason}
+        error:badarg -> {error, badarg}
     end.
 
-
-
-%% Closes a port in a safe way. Returns ok.
-
-drv_close(Port) ->
-    Save = erlang:dt_spread_tag(false),
+get_cwd() ->
+    try get_cwd_nif() of
+        {ok, RawPath} -> {ok, decode_path(RawPath)};
+        {error, Reason} -> {error, Reason}
+    catch
+        error:badarg -> {error, badarg}
+    end.
+set_cwd(Path) ->
     try
-	try erlang:port_close(Port) catch error:_ -> ok end,
-	receive %% Ugly workaround in case the caller==owner traps exits
-	    {'EXIT', Port, _Reason} -> 
-		ok
-	after 0 -> 
-		ok
-	end
-    after
-	erlang:dt_restore_tag(Save)
+        case is_path_translatable(Path) of
+            true -> set_cwd_nif(encode_path(Path));
+            false -> {error, no_translation}
+        end
+    catch
+        error:badarg -> {error, badarg}
     end.
 
-
-
-%% Issues a command to a port and gets the response.
-%% If Port is {Driver, Portopts} a port is first opened and 
-%% then closed after the result has been received.
-%% Returns {ok, Result} or {error, Reason}.
-
-drv_command(Port, Command) ->
-    drv_command(Port, Command, undefined).
-
-drv_command(Port, Command, R) when is_binary(Command) ->
-    drv_command(Port, Command, true, R);
-drv_command(Port, Command, R) ->
-    try erlang:iolist_size(Command) of
-	_ ->
-	    drv_command(Port, Command, true, R)
+delete(Path) ->
+    try
+        del_file_nif(encode_path(Path))
     catch
-	error:Reason ->
-	    {error, Reason}
+        error:badarg -> {error, badarg}
     end.
 
-drv_command(Port, Command, Validated, R) when is_port(Port) ->
-    Save = erlang:dt_spread_tag(false),
-    try erlang:port_command(Port, erlang:dt_append_vm_tag_data(Command)) of
-	true ->
-	    drv_get_response(Port, R)
+rename(Source, Destination) ->
+    try
+        rename_nif(encode_path(Source), encode_path(Destination))
     catch
-	%% If the Command is valid, knowing that the port is a port,
-	%% a badarg error must mean it is a dead port, that is:
-	%% a currently invalid filehandle, -> einval, not badarg.
-	error:badarg when Validated ->
-	    {error, einval};
-	error:badarg ->
-	    try erlang:iolist_size(Command) of
-		_ -> % Valid
-		    {error, einval}
-	    catch
-		error:_ ->
-		    {error, badarg}
-	    end;
-	error:Reason ->
-	    {error, Reason}
-    after
-	erlang:dt_restore_tag(Save)
-    end;
-drv_command({Driver, Portopts}, Command, Validated, R) ->
-    case drv_open(Driver, Portopts) of
-	{ok, Port} ->
-	    Result = drv_command(Port, Command, Validated, R),
-	    drv_close(Port),
-	    Result;
-	Error ->
-	    Error
+        error:badarg -> {error, badarg}
     end.
-drv_command_nt(Port, Command, R) when is_port(Port) ->
-    Save = erlang:dt_spread_tag(false),
-    try erlang:port_command(Port, Command) of
-	true ->
-	    drv_get_response(Port, R)
+make_dir(Path) ->
+    try
+        make_dir_nif(encode_path(Path))
     catch
-	error:badarg ->
-	    try erlang:iolist_size(Command) of
-		_ -> % Valid
-		    {error, einval}
-	    catch
-		error:_ ->
-		    {error, badarg}
-	    end;
-	error:Reason ->
-	    {error, Reason}
-    after
-	erlang:dt_restore_tag(Save)
+        error:badarg -> {error, badarg}
     end.
-
-
-    
-%% Receives the response from a driver port.
-%% Returns: {ok, ListOrBinary}|{error, Reason}
-
-drv_get_response(Port, undefined) ->
-    drv_get_response(Port);
-drv_get_response(Port, Fun) when is_function(Fun, 1) ->
-    Fun(Port).
-
-drv_get_response(Port) ->
-    erlang:bump_reductions(100),
-    receive
-	{Port, {data, [Response|Rest] = Data}} ->
-	    try translate_response(Response, Rest)
-	    catch
-		error:Reason ->
-		    {error, {bad_response_from_port, Data, 
-			     {Reason, erlang:get_stacktrace()}}}
-	    end;
-	{'EXIT', Port, Reason} ->
-	    {error, {port_died, Reason}}
+del_dir(Path) ->
+    try
+        del_dir_nif(encode_path(Path))
+    catch
+        error:badarg -> {error, badarg}
     end.
-
-
-%%%-----------------------------------------------------------------
-%%% Utility functions.
-
-%% Converts a list of mode atoms into a mode word for the driver.
-%% Returns {Mode, Portopts, Setopts} where Portopts is a list of 
-%% options for erlang:open_port/2 and Setopts is a list of 
-%% setopt commands to send to the port, or error Reason upon failure.
-
-open_mode(List) when is_list(List) ->
-    case open_mode(List, 0, [], []) of
-	{Mode, Portopts, Setopts} when Mode band 
-			  (?EFILE_MODE_READ bor ?EFILE_MODE_WRITE) 
-			  =:= 0 ->
-	    {Mode bor ?EFILE_MODE_READ, Portopts, Setopts};
-	Other ->
-	    Other
+make_link(Existing, New) ->
+    try
+        make_hard_link_nif(encode_path(Existing), encode_path(New))
+    catch
+        error:badarg -> {error, badarg}
     end.
-
-open_mode([raw|Rest], Mode, Portopts, Setopts) ->
-    open_mode(Rest, Mode, Portopts, Setopts);
-open_mode([read|Rest], Mode, Portopts, Setopts) ->
-    open_mode(Rest, Mode bor ?EFILE_MODE_READ, Portopts, Setopts);
-open_mode([write|Rest], Mode, Portopts, Setopts) ->
-    open_mode(Rest, Mode bor ?EFILE_MODE_WRITE, Portopts, Setopts);
-open_mode([binary|Rest], Mode, Portopts, Setopts) ->
-    open_mode(Rest, Mode, [binary | Portopts], Setopts);
-open_mode([compressed|Rest], Mode, Portopts, Setopts) ->
-    open_mode(Rest, Mode bor ?EFILE_COMPRESSED, Portopts, Setopts);
-open_mode([append|Rest], Mode, Portopts, Setopts) ->
-    open_mode(Rest, Mode bor ?EFILE_MODE_APPEND bor ?EFILE_MODE_WRITE, 
-	      Portopts, Setopts);
-open_mode([exclusive|Rest], Mode, Portopts, Setopts) ->
-    open_mode(Rest, Mode bor ?EFILE_MODE_EXCL, Portopts, Setopts);
-open_mode([sync|Rest], Mode, Portopts, Setopts) ->
-    open_mode(Rest, Mode bor ?EFILE_MODE_SYNC, Portopts, Setopts);
-open_mode([delayed_write|Rest], Mode, Portopts, Setopts) ->
-    open_mode([{delayed_write, 64*1024, 2000}|Rest], Mode,
-	      Portopts, Setopts);
-open_mode([{delayed_write, Size, Delay}|Rest], Mode, Portopts, Setopts) 
-  when is_integer(Size), 0 =< Size, is_integer(Delay), 0 =< Delay ->
-    if
-	Size < ?LARGEFILESIZE, Delay < 1 bsl 64 ->
-	    open_mode(Rest, Mode, Portopts, 
-		      [<<?FILE_SETOPT, ?FILE_OPT_DELAYED_WRITE,
-			Size:64, Delay:64>> 
-		       | Setopts]);
-	true ->
-	    einval
-    end;
-open_mode([read_ahead|Rest], Mode, Portopts, Setopts) ->
-    open_mode([{read_ahead, 64*1024}|Rest], Mode, Portopts, Setopts);
-open_mode([{read_ahead, Size}|Rest], Mode, Portopts, Setopts)
-  when is_integer(Size), 0 =< Size ->
-    if
-	Size < ?LARGEFILESIZE ->
-	    open_mode(Rest, Mode, Portopts,
-		      [<<?FILE_SETOPT, ?FILE_OPT_READ_AHEAD,
-			Size:64>> | Setopts]);
-	true ->
-	    einval
-    end;
-open_mode([], Mode, Portopts, Setopts) ->
-    {Mode, reverse(Portopts), reverse(Setopts)};
-open_mode(_, _Mode, _Portopts, _Setopts) ->
-    badarg.
-
-
-
-%% Converts a position tuple {bof, X} | {cur, X} | {eof, X} into
-%% {Offset, OriginCode} for the driver.
-%% Returns badarg upon failure.
-
-lseek_position(Pos)
-  when is_integer(Pos) ->
-    lseek_position({bof, Pos});
-lseek_position(bof) ->
-    lseek_position({bof, 0});
-lseek_position(cur) ->
-    lseek_position({cur, 0});
-lseek_position(eof) ->
-    lseek_position({eof, 0});
-lseek_position({bof, Offset})
-  when is_integer(Offset) ->
-    {Offset, ?EFILE_SEEK_SET};
-lseek_position({cur, Offset})
-  when is_integer(Offset) ->
-    {Offset, ?EFILE_SEEK_CUR};
-lseek_position({eof, Offset})
-  when is_integer(Offset) ->
-    {Offset, ?EFILE_SEEK_END};
-lseek_position(_) ->
-    badarg.
-
-
-
-%% Translates the response from the driver into 
-%% {ok, Result} or {error, Reason}.
-
--dialyzer({no_improper_lists, translate_response/2}).
-translate_response(?FILE_RESP_OK, []) ->
-    ok;
-translate_response(?FILE_RESP_ERROR, List) when is_list(List) ->
-    {error, list_to_atom(List)};
-translate_response(?FILE_RESP_NUMBER, List) ->
-    {N, []} = get_uint64(List),
-    {ok, N};
-translate_response(?FILE_RESP_DATA, List) ->
-    {_N, _Data} = ND = get_uint64(List),
-    {ok, ND};
-translate_response(?FILE_RESP_INFO, List) when is_list(List) ->
-    {ok, transform_info(List)};
-translate_response(?FILE_RESP_NUMERR, L0) ->
-    {N, L1} = get_uint64(L0),
-    {error, {N, list_to_atom(L1)}};
-translate_response(?FILE_RESP_LDATA, List) ->
-    {ok, transform_ldata(List)};
-translate_response(?FILE_RESP_N2DATA, 
-		   <<Offset:64, 0:64, Size:64>>) ->
-    {ok, {Size, Offset, eof}};
-translate_response(?FILE_RESP_N2DATA, 
-		   [<<Offset:64, 0:64, Size:64>> | <<>>]) ->
-    {ok, {Size, Offset, eof}};
-translate_response(?FILE_RESP_N2DATA = X, 
-		   [<<_:64, 0:64, _:64>> | _] = Data) ->
-    {error, {bad_response_from_port, [X | Data]}};
-translate_response(?FILE_RESP_N2DATA = X, 
-		   [<<_:64, _:64, _:64>> | <<>>] = Data) ->
-    {error, {bad_response_from_port, [X | Data]}};
-translate_response(?FILE_RESP_N2DATA, 
-		   [<<Offset:64, _ReadSize:64, Size:64>> | D]) ->
-    {ok, {Size, Offset, D}};
-translate_response(?FILE_RESP_N2DATA = X, L0) when is_list(L0) ->
-    {Offset, L1}    = get_uint64(L0),
-    {ReadSize, L2}  = get_uint64(L1),
-    {Size, L3}      = get_uint64(L2),
-    case {ReadSize, L3} of
-	{0, []} ->
-	    {ok, {Size, Offset, eof}};
-	{0, _} ->
-	    {error, {bad_response_from_port, [X | L0]}};
-	{_, []} ->
-	    {error, {bad_response_from_port, [X | L0]}};
-	_ ->
-	    {ok, {Size, Offset, L3}}
-    end;
-translate_response(?FILE_RESP_EOF, []) ->
-    eof;
-translate_response(?FILE_RESP_FNAME, Data) ->
-    {fname, Data};
-translate_response(?FILE_RESP_LFNAME, Data) ->
-    {lfname, Data};
-translate_response(?FILE_RESP_ALL_DATA, Data) ->
-    {ok, Data};
-translate_response(X, Data) ->
-    {error, {bad_response_from_port, [X | Data]}}.
-
-transform_info([
-    Hsize1, Hsize2, Hsize3, Hsize4, 
-    Lsize1, Lsize2, Lsize3, Lsize4,
-    Type1,  Type2,  Type3,  Type4,
-    Atime1, Atime2, Atime3, Atime4, Atime5, Atime6, Atime7, Atime8,
-    Mtime1, Mtime2, Mtime3, Mtime4, Mtime5, Mtime6, Mtime7, Mtime8,
-    Ctime1, Ctime2, Ctime3, Ctime4, Ctime5, Ctime6, Ctime7, Ctime8,
-    Mode1,  Mode2,  Mode3,  Mode4,
-    Links1, Links2, Links3, Links4,
-    Major1, Major2, Major3, Major4,
-    Minor1, Minor2, Minor3, Minor4,
-    Inode1, Inode2, Inode3, Inode4,
-    Uid1,   Uid2,   Uid3,   Uid4,
-    Gid1,   Gid2,   Gid3,   Gid4,
-    Access1,Access2,Access3,Access4]) ->
-    #file_info {
-		size   = uint32(Hsize1,Hsize2,Hsize3,Hsize4)*16#100000000 + uint32(Lsize1,Lsize2,Lsize3,Lsize4),
-		type   = file_type(uint32(Type1,Type2,Type3,Type4)),
-		access = file_access(uint32(Access1,Access2,Access3,Access4)),
-		atime  = sint64(Atime1, Atime2, Atime3, Atime4, Atime5, Atime6, Atime7, Atime8),
-		mtime  = sint64(Mtime1, Mtime2, Mtime3, Mtime4, Mtime5, Mtime6, Mtime7, Mtime8),
-		ctime  = sint64(Ctime1, Ctime2, Ctime3, Ctime4, Ctime5, Ctime6, Ctime7, Ctime8),
-		mode   = uint32(Mode1,Mode2,Mode3,Mode4),
-		links  = uint32(Links1,Links2,Links3,Links4),
-		major_device = uint32(Major1,Major2,Major3,Major4),
-		minor_device = uint32(Minor1,Minor2,Minor3,Minor4),
-		inode = uint32(Inode1,Inode2,Inode3,Inode4),
-		uid   = uint32(Uid1,Uid2,Uid3,Uid4),
-		gid   = uint32(Gid1,Gid2,Gid3,Gid4)
-	    }.
-    
-    
-file_type(1) -> device;
-file_type(2) -> directory;
-file_type(3) -> regular;
-file_type(4) -> symlink;
-file_type(_) -> other.
-
-file_access(0) -> none;   
-file_access(1) -> write;
-file_access(2) -> read;
-file_access(3) -> read_write.
-
-int_to_int32bytes(Int) when is_integer(Int) ->
-    <<Int:32>>;
-int_to_int32bytes(undefined) ->
-    <<-1:32>>.
-
-int_to_int64bytes(Int) when is_integer(Int) ->
-    <<Int:64/signed>>.
-
-
-sint64(I1,I2,I3,I4,I5,I6,I7,I8) when I1 > 127 ->
-    ((I1 bsl 56) bor (I2 bsl 48) bor (I3 bsl 40) bor (I4 bsl 32) bor
-	(I5 bsl 24) bor (I6 bsl 16) bor (I7 bsl  8) bor I8) - (1 bsl 64);
-sint64(I1,I2,I3,I4,I5,I6,I7,I8) ->
-    ((I1 bsl 56) bor (I2 bsl 48) bor (I3 bsl 40) bor (I4 bsl 32) bor
-	(I5 bsl 24) bor (I6 bsl 16) bor (I7 bsl  8) bor I8).
-
-
-uint32(X1,X2,X3,X4) ->
-    (X1 bsl 24) bor (X2 bsl 16) bor (X3 bsl 8) bor X4.
-
-get_uint64(L0) ->
-    {X1, L1} = get_uint32(L0),
-    {X2, L2} = get_uint32(L1),
-    {(X1 bsl 32) bor X2, L2}.
-
-get_uint32([X1,X2,X3,X4|List]) ->
-    {(((((X1 bsl 8) bor X2) bsl 8) bor X3) bsl 8) bor X4, List}.
-
-
-%% Binary mode
-transform_ldata(<<0:32, 0:32>>) ->
-    [];
-transform_ldata([<<0:32, N:32, Sizes/binary>> | Datas]) ->
-    transform_ldata(N, Sizes, Datas, []);
-%% List mode
-transform_ldata([_,_,_,_,_,_,_,_|_] = L0) ->
-    {0, L1} = get_uint32(L0),
-    {N, L2} = get_uint32(L1),
-    transform_ldata(N, L2, []).
-
-%% List mode
-transform_ldata(0, List, Sizes) ->
-    transform_ldata(0, List, reverse(Sizes), []);
-transform_ldata(N, L0, Sizes) ->
-    {Size, L1} = get_uint64(L0),
-    transform_ldata(N-1, L1, [Size | Sizes]).
-
-%% Binary mode
-transform_ldata(1, <<0:64>>, <<>>, R) ->
-    reverse(R, [eof]);
-transform_ldata(1, <<Size:64>>, Data, R) 
-  when byte_size(Data) =:= Size ->
-    reverse(R, [Data]);
-transform_ldata(N, <<0:64, Sizes/binary>>, [<<>> | Datas], R) ->
-    transform_ldata(N-1, Sizes, Datas, [eof | R]);
-transform_ldata(N, <<Size:64, Sizes/binary>>, [Data | Datas], R) 
-  when byte_size(Data) =:= Size ->
-    transform_ldata(N-1, Sizes, Datas, [Data | R]);
-%% List mode
-transform_ldata(0, [], [], R) ->
-    reverse(R);
-transform_ldata(0, List, [0 | Sizes], R) ->
-    transform_ldata(0, List, Sizes, [eof | R]);
-transform_ldata(0, List, [Size | Sizes], R) ->
-    {Front, Rear} = lists_split(List, Size),
-    transform_ldata(0, Rear, Sizes, [Front | R]).
-
-lists_split(List, 0) when is_list(List) ->
-    {[], List};
-lists_split(List, N) when is_list(List), is_integer(N), N < 0 ->
-    erlang:error(badarg, [List, N]);
-lists_split(List, N) when is_list(List), is_integer(N) ->
-    case lists_split(List, N, []) of
-	premature_end_of_list ->
-	    erlang:error(badarg, [List, N]);
-	Result ->
-	    Result
+make_symlink(Existing, New) ->
+    try
+        make_soft_link_nif(encode_path(Existing), encode_path(New))
+    catch
+        error:badarg -> {error, badarg}
     end.
 
-lists_split(List, 0, Rev) ->
-    {reverse(Rev), List};
-lists_split([], _, _) ->
-    premature_end_of_list;
-lists_split([Hd | Tl], N, Rev) ->
-    lists_split(Tl, N-1, [Hd | Rev]).
-
-%% We KNOW that lists:reverse/2 is a BIF.
-
-reverse(X) -> lists:reverse(X, []).
-reverse(L, T) -> lists:reverse(L, T).
+altname(Path) ->
+    try altname_nif(encode_path(Path)) of
+        {ok, RawPath} -> {ok, decode_path(RawPath)};
+        Other -> Other
+    catch
+        error:badarg -> {error, badarg}
+    end.
 
-% Will add zero termination too
-% The 'EXIT' tuple from a bad argument will eventually generate an error
-% in list_to_binary, which is caught and generates the {error,badarg} return
-pathname(File) ->
-    (catch prim_file:internal_name2native(File)).
+list_dir_nif(_Path) ->
+    erlang:nif_error(undef).
+read_link_nif(_Path) ->
+    erlang:nif_error(undef).
+read_info_nif(_Path, _FollowLinks) ->
+    erlang:nif_error(undef).
+make_hard_link_nif(_Existing, _New) ->
+    erlang:nif_error(undef).
+make_soft_link_nif(_Existing, _New) ->
+    erlang:nif_error(undef).
+rename_nif(_Source, _Destination) ->
+    erlang:nif_error(undef).
+make_dir_nif(_Path) ->
+    erlang:nif_error(undef).
+del_file_nif(_Path) ->
+    erlang:nif_error(undef).
+del_dir_nif(_Path) ->
+    erlang:nif_error(undef).
+get_device_cwd_nif(_DevicePath) ->
+    erlang:nif_error(undef).
+set_cwd_nif(_Path) ->
+    erlang:nif_error(undef).
+get_cwd_nif() ->
+    erlang:nif_error(undef).
+altname_nif(_Path) ->
+    erlang:nif_error(undef).
 
+%%
+%% General helper functions.
+%%
 
-%% proplist:get_value/3
-plgv(K, [{K, V}|_], _) -> V;
-plgv(K, [_|KVs], D)    -> plgv(K, KVs, D);
-plgv(_, [], D)         -> D.
+%% We know for certain that lists:reverse/2 is a BIF, so it's safe to use it
+%% even though this module is preloaded.
+reverse_list(List) -> lists:reverse(List).
+
+proplist_get_value(_Key, [], Default) ->
+    Default;
+proplist_get_value(Key, [{Key, Value} | _Rest], _Default) ->
+    Value;
+proplist_get_value(Key, [Key | _Rest], _Default) ->
+    true;
+proplist_get_value(Key, [_Other | Rest], Default) ->
+    proplist_get_value(Key, Rest, Default).
+
+encode_path(Path) ->
+    prim_file:internal_name2native(Path).
+decode_path(NativePath) when is_binary(NativePath) ->
+    prim_file:internal_native2name(NativePath).
+
+is_path_translatable(Path) when is_list(Path) ->
+    true;
+is_path_translatable(Path) ->
+    prim_file:is_translatable(Path).
 
-%%
 %% We don't actually want this here
+%%
 %% We want to use posix time in all prim but erl_prim_loader makes that tricky
 %% It is probably needed to redo the whole erl_prim_loader
 
-from_seconds(Seconds, posix) when is_integer(Seconds) ->
+from_posix_seconds(Seconds, posix) when is_integer(Seconds) ->
     Seconds;
-from_seconds(Seconds, universal) when is_integer(Seconds) ->
+from_posix_seconds(Seconds, universal) when is_integer(Seconds) ->
     erlang:posixtime_to_universaltime(Seconds);
-from_seconds(Seconds, local) when is_integer(Seconds) ->
+from_posix_seconds(Seconds, local) when is_integer(Seconds) ->
     erlang:universaltime_to_localtime(erlang:posixtime_to_universaltime(Seconds)).
 
-to_seconds(Seconds, posix) when is_integer(Seconds) ->
+to_posix_seconds(Seconds, posix) when is_integer(Seconds) ->
     Seconds;
-to_seconds({_,_} = Datetime, universal) ->
+to_posix_seconds({_,_} = Datetime, universal) ->
     erlang:universaltime_to_posixtime(Datetime);
-to_seconds({_,_} = Datetime, local) ->
+to_posix_seconds({_,_} = Datetime, local) ->
     erlang:universaltime_to_posixtime(erlang:localtime_to_universaltime(Datetime)).
diff --git a/erts/preloaded/src/prim_inet.erl b/erts/preloaded/src/prim_inet.erl
index 017a706a8b..2a3605260d 100644
--- a/erts/preloaded/src/prim_inet.erl
+++ b/erts/preloaded/src/prim_inet.erl
@@ -31,7 +31,7 @@
 -export([connect/3, connect/4, async_connect/4]).
 -export([accept/1, accept/2, async_accept/2]).
 -export([shutdown/2]).
--export([send/2, send/3, sendto/4, sendmsg/3]).
+-export([send/2, send/3, sendto/4, sendmsg/3, sendfile/4]).
 -export([recv/2, recv/3, async_recv/3]).
 -export([unrecv/2]).
 -export([recvfrom/2, recvfrom/3]).
@@ -500,6 +500,55 @@ sendmsg(S, #sctp_sndrcvinfo{}=SRI, Data) when is_port(S) ->
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%
+%% SENDFILE(outsock(), Fd, Offset, Length) -> {ok,BytesSent} | {error, Reason}
+%%
+%% send Length data bytes from a file handle, to a socket, starting at Offset
+%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% "sendfile" is for TCP:
+
+sendfile(S, FileHandle, Offset, Length)
+        when not is_port(S);
+             not is_binary(FileHandle);
+             not is_integer(Offset);
+             not is_integer(Length) ->
+    {error, badarg};
+sendfile(S, FileHandle, Offset, Length) ->
+    case erlang:port_info(S, connected) of
+        {connected, Pid} when Pid =:= self() ->
+            sendfile_1(S, FileHandle, Offset, Length);
+        {connected, Pid} when Pid =/= self() ->
+            {error, not_owner};
+        _Other ->
+            {error, einval}
+    end.
+
+sendfile_1(S, FileHandle, Offset, 0) ->
+    sendfile_1(S, FileHandle, Offset, (1 bsl 63) - 1);
+sendfile_1(_S, _FileHandle, Offset, Length) when
+         Offset < 0; Offset > ((1 bsl 63) - 1);
+         Length < 0; Length > ((1 bsl 63) - 1) ->
+    {error, einval};
+sendfile_1(S, FileHandle, Offset, Length) ->
+    Args = [FileHandle,
+            ?int64(Offset),
+            ?int64(Length)],
+    case ctl_cmd(S, ?TCP_REQ_SENDFILE, Args) of
+        {ok, []} ->
+            receive
+                {sendfile, S, {ok, SentLow, SentHigh}} ->
+                    {ok, SentLow bor (SentHigh bsl 32)};
+                {sendfile, S, {error, Reason}} ->
+                    {error, Reason};
+                {'EXIT', S, _Reason} ->
+                    {error, closed}
+            end;
+        {error, Reason} ->
+            {error, Reason}
+    end.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%
 %% RECV(insock(), Length, [Timeout]) -> {ok,Data} | {error, Reason}
 %%
 %% receive Length data bytes from a socket
diff --git a/erts/start_scripts/Makefile b/erts/start_scripts/Makefile
index 20fea99016..5a47ad9616 100644
--- a/erts/start_scripts/Makefile
+++ b/erts/start_scripts/Makefile
@@ -171,8 +171,7 @@ $(ERL_TOP)/bin/no_dot_erlang.script:
 	  $(ERLC) $(SCRIPT_PATH) +no_warn_sasl +otp_build +no_dot_erlang -o $@ $(SS_ROOT)/no_dot_erlang.rel )
 
 ## Special target used from system/build/Makefile for source code release bootstrap.
-## Add no_dot_erlang after next release
-bootstrap_scripts: $(SS_ROOT)/start_clean.rel
+bootstrap_scripts: $(SS_ROOT)/start_clean.rel $(SS_ROOT)/no_dot_erlang.rel
 	$(V_at)$(INSTALL_DIR) $(TESTROOT)/bin
 	$(V_at)$(INSTALL_DIR) $(SS_TMP)
 	$(V_at)( cd $(SS_TMP) && \
@@ -181,6 +180,10 @@ bootstrap_scripts: $(SS_ROOT)/start_clean.rel
 	$(V_at)( cd $(SS_TMP) && \
 	  $(ERLC) $(BOOTSTRAP_SCRIPT_PATH) +otp_build +no_module_tests \
 	    -o $(TESTROOT)/bin/start_clean.script $(SS_ROOT)/start_clean.rel )
+	$(V_at)( cd $(SS_TMP) && \
+	  $(ERLC) $(BOOTSTRAP_SCRIPT_PATH) +otp_build +no_module_tests \
+	    -o $(TESTROOT)/bin/no_dot_erlang.script $(SS_ROOT)/no_dot_erlang.rel )
+
 
 clean:
 	$(V_at)$(RM) $(REL_SCRIPTS) $(INSTALL_SCRIPTS)
diff --git a/erts/test/erlc_SUITE.erl b/erts/test/erlc_SUITE.erl
index 237558a129..394ecc8964 100644
--- a/erts/test/erlc_SUITE.erl
+++ b/erts/test/erlc_SUITE.erl
@@ -257,7 +257,7 @@ erlc() ->
 make_dep_options(Config) ->
     {SrcDir,OutDir,Cmd} = get_cmd(Config),
     FileName = filename:join(SrcDir, "erl_test_ok.erl"),
-
+    BeamFileName = filename:join(OutDir, "erl_test_ok.beam"),
 
     DepRE = ["/erl_test_ok[.]beam: \\\\$",
              "/system_test/erlc_SUITE_data/src/erl_test_ok[.]erl \\\\$",
@@ -285,22 +285,29 @@ make_dep_options(Config) ->
      "missing.hrl$",
      "_OK_"],
 
+    file:delete(BeamFileName),
+
     %% Test plain -M
     run(Config, Cmd, FileName, "-M", DepRE),
+    false = exists(BeamFileName),
 
     %% Test -MF File
     DepFile = filename:join(OutDir, "my.deps"),
     run(Config, Cmd, FileName, "-MF "++DepFile, ["_OK_"]),
     {ok,MFBin} = file:read_file(DepFile),
     verify_result(binary_to_list(MFBin)++["_OK_"], DepRE),
+    false = exists(BeamFileName),
 
     %% Test -MD
     run(Config, Cmd, FileName, "-MD", ["_OK_"]),
     MDFile = filename:join(OutDir, "erl_test_ok.Pbeam"),
     {ok,MFBin} = file:read_file(MDFile),
+    file:delete(MDFile), %% used further down!
+    false = exists(BeamFileName),
 
     %% Test -M -MT Target
     run(Config, Cmd, FileName, "-M -MT target", DepRETarget),
+    false = exists(BeamFileName),
 
     %% Test -MF File -MT Target
     TargetDepFile = filename:join(OutDir, "target.deps"),
@@ -308,23 +315,110 @@ make_dep_options(Config) ->
         ["_OK_"]),
     {ok,TargetBin} = file:read_file(TargetDepFile),
     verify_result(binary_to_list(TargetBin)++["_OK_"], DepRETarget),
+    file:delete(TargetDepFile),
+    false = exists(BeamFileName),
 
     %% Test -MD -MT Target
     run(Config, Cmd, FileName, "-MD -MT target", ["_OK_"]),
     TargetMDFile = filename:join(OutDir, "erl_test_ok.Pbeam"),
     {ok,TargetBin} = file:read_file(TargetMDFile),
+    file:delete(TargetDepFile),
+    false = exists(BeamFileName),
 
     %% Test -M -MQ Target. (Note: Passing a $ on the command line
     %% portably for Unix and Windows is tricky, so we will just test
     %% that MQ works at all.)
     run(Config, Cmd, FileName, "-M -MQ target", DepRETarget),
+    false = exists(BeamFileName),
 
     %% Test -M -MP
     run(Config, Cmd, FileName, "-M -MP", DepREMP),
+    false = exists(BeamFileName),
 
     %% Test -M -MG
     MissingHeader = filename:join(SrcDir, "erl_test_missing_header.erl"),
     run(Config, Cmd, MissingHeader, "-M -MG", DepREMissing),
+    false = exists(BeamFileName),
+
+    %%
+    %% check the above variants with side-effect -MMD
+    %%
+
+    %% since compiler is run on the erlang code a warning will be
+    %% issued by the compiler, match that.
+    WarningRE = "/system_test/erlc_SUITE_data/src/erl_test_ok.erl:[0-9]+: "
+        "Warning: function foo/0 is unused$",
+    ErrorRE = "/system_test/erlc_SUITE_data/src/erl_test_missing_header.erl:"
+        "[0-9]+: can't find include file \"missing.hrl\"$",
+
+    DepRE_MMD = insert_before("_OK_", WarningRE, DepRE),
+    DepRETarget_MMD = insert_before("_OK_", WarningRE, DepRETarget),
+    DepREMP_MMD = insert_before("_OK_",WarningRE,DepREMP),
+    DepREMissing_MMD = (insert_before("_OK_",ErrorRE,DepREMissing)--
+                            ["_OK_"]) ++ ["_ERROR_"],
+    CompRE = [WarningRE,"_OK_"],
+
+
+    %% Test plain -MMD -M
+    run(Config, Cmd, FileName, "-MMD -M", DepRE_MMD),
+    true = exists(BeamFileName),
+    file:delete(BeamFileName),
+
+    %% Test -MMD -MF File
+    DepFile = filename:join(OutDir, "my.deps"),
+    run(Config, Cmd, FileName, "-MMD -MF "++DepFile, CompRE),
+    {ok,MFBin} = file:read_file(DepFile),
+    verify_result(binary_to_list(MFBin)++["_OK_"], DepRE),
+    true = exists(BeamFileName),
+    file:delete(BeamFileName),
+
+    %% Test -MMD -MD
+    run(Config, Cmd, FileName, "-MMD -MD", CompRE),
+    MDFile = filename:join(OutDir, "erl_test_ok.Pbeam"),
+    {ok,MFBin} = file:read_file(MDFile),
+    file:delete(MDFile), %% used further down!
+    true = exists(BeamFileName),
+    file:delete(BeamFileName),
+
+    %% Test -MMD -M -MT Target
+    run(Config, Cmd, FileName, "-MMD -M -MT target", DepRETarget_MMD),
+    true = exists(BeamFileName),
+    file:delete(BeamFileName),
+
+    %% Test -MMD -MF File -MT Target
+    TargetDepFile = filename:join(OutDir, "target.deps"),
+    run(Config, Cmd, FileName, "-MMD -MF "++TargetDepFile++" -MT target",
+        CompRE),
+    {ok,TargetBin} = file:read_file(TargetDepFile),
+    verify_result(binary_to_list(TargetBin)++["_OK_"], DepRETarget),
+    file:delete(TargetDepFile),
+    true = exists(BeamFileName),
+    file:delete(BeamFileName),
+
+    %% Test -MMD -MD -MT Target
+    run(Config, Cmd, FileName, "-MMD -MD -MT target", CompRE),
+    TargetMDFile = filename:join(OutDir, "erl_test_ok.Pbeam"),
+    {ok,TargetBin} = file:read_file(TargetMDFile),
+    file:delete(TargetDepFile),
+    true = exists(BeamFileName),
+    file:delete(BeamFileName),
+
+    %% Test -MMD -M -MQ Target. (Note: Passing a $ on the command line
+    %% portably for Unix and Windows is tricky, so we will just test
+    %% that MQ works at all.)
+    run(Config, Cmd, FileName, "-MMD -M -MQ target", DepRETarget_MMD),
+    true = exists(BeamFileName),
+    file:delete(BeamFileName),
+
+    %% Test -MMD -M -MP
+    run(Config, Cmd, FileName, "-MMD -M -MP", DepREMP_MMD),
+    true = exists(BeamFileName),
+    file:delete(BeamFileName),
+
+    %% Test -MMD -M -MG
+    MissingHeader = filename:join(SrcDir, "erl_test_missing_header.erl"),
+    run(Config, Cmd, MissingHeader, "-MMD -M -MG", DepREMissing_MMD),
+    false = exists(BeamFileName),
     ok.
 
 %% Runs a command.
@@ -341,6 +435,12 @@ verify_result(Result, Expect) ->
     io:format("Expected: ~p", [Expect]),
     match_messages(Messages, Expect).
 
+%% insert What before Item, crash if Item is not found
+insert_before(Item, What, [Item|List]) ->
+    [What,Item|List];
+insert_before(Item, What, [Other|List]) ->
+    [Other|insert_before(Item, What, List)].
+
 split([$\n|Rest], Current, Lines) ->
     split(Rest, [], [lists:reverse(Current)|Lines]);
 split([$\r|Rest], Current, Lines) ->
diff --git a/erts/test/erlexec_SUITE.erl b/erts/test/erlexec_SUITE.erl
index 44d7f63387..db993abe52 100644
--- a/erts/test/erlexec_SUITE.erl
+++ b/erts/test/erlexec_SUITE.erl
@@ -59,7 +59,7 @@ otp_8209(Config) when is_list(Config) ->
     {ok,[[PName]]} = init:get_argument(progname),
     SNameS = "erlexec_test_01",
     SName = list_to_atom(SNameS++"@"++
-			 hd(tl(string:tokens(atom_to_list(node()),"@")))),
+			 hd(tl(string:lexemes(atom_to_list(node()),"@")))),
     Cmd = PName ++ " dummy_param -sname "++SNameS++" -setcookie "++
 	atom_to_list(erlang:get_cookie()),
     open_port({spawn,Cmd},[]),
@@ -75,7 +75,7 @@ cleanup_node(SNameS,0) ->
     {error, {would_not_die,list_to_atom(SNameS)}};
 cleanup_node(SNameS,N) ->
     SName = list_to_atom(SNameS++"@"++
-			 hd(tl(string:tokens(atom_to_list(node()),"@")))),
+			 hd(tl(string:lexemes(atom_to_list(node()),"@")))),
     case rpc:call(SName,init,stop,[]) of
 	{badrpc,_} ->
 	    ok;
@@ -322,7 +322,7 @@ zdbbl_dist_buf_busy_limit(Config) when is_list(Config) ->
     {ok,[[PName]]} = init:get_argument(progname),
     SNameS = "erlexec_test_02",
     SName = list_to_atom(SNameS++"@"++
-                         hd(tl(string:tokens(atom_to_list(node()),"@")))),
+                         hd(tl(string:lexemes(atom_to_list(node()),"@")))),
     Cmd = PName ++ " -sname "++SNameS++" -setcookie "++
         atom_to_list(erlang:get_cookie()) ++
 	" +zdbbl " ++ integer_to_list(LimKB),
@@ -400,7 +400,7 @@ emu_args(CmdLineArgs) ->
     {ok,[[Erl]]} = init:get_argument(progname),
     EmuCL = os:cmd(Erl ++ " -emu_args_exit " ++ CmdLineArgs),
     io:format("EmuCL = ~ts", [EmuCL]),
-    split_emu_clt(string:tokens(EmuCL, [$ ,$\t,$\n,$\r])).
+    split_emu_clt(string:lexemes(EmuCL, [$ ,$\t,$\n,$\r])).
 
 split_emu_clt(EmuCLT) ->
     split_emu_clt(EmuCLT, [], [], [], emu).
diff --git a/erts/test/install_SUITE.erl b/erts/test/install_SUITE.erl
index d6c6d6f30e..324b398caa 100644
--- a/erts/test/install_SUITE.erl
+++ b/erts/test/install_SUITE.erl
@@ -580,7 +580,7 @@ end_per_testcase(_Case, _Config) ->
     ok.
 
 make_dirs(Root, Suffix) ->
-    do_make_dirs(Root, string:tokens(Suffix, [$/])).
+    do_make_dirs(Root, string:lexemes(Suffix, [$/])).
 
 do_make_dirs(_Root, []) ->
     "";
@@ -709,4 +709,4 @@ join("") ->
 join([""|Ds]) ->
     join(Ds);
 join([D|Ds]) ->
-    "/" ++ string:strip(D, both, $/) ++ join(Ds).
+    "/" ++ string:trim(D, both, [$/]) ++ join(Ds).
diff --git a/erts/test/nt_SUITE.erl b/erts/test/nt_SUITE.erl
index 624e5484ba..3081b58835 100644
--- a/erts/test/nt_SUITE.erl
+++ b/erts/test/nt_SUITE.erl
@@ -117,7 +117,7 @@ wait_for_node(Name) ->
     do_wait_for_it(FullName,30).
 
 make_full_name(Name) ->
-    [_,Suffix] = string:tokens(atom_to_list(node()),"@"),
+    [_,Suffix] = string:lexemes(atom_to_list(node()),"@"),
     list_to_atom(Name ++ "@" ++ Suffix).
 
 
@@ -171,7 +171,7 @@ service_env(Config) when is_list(Config) ->
                     ["ERLSRV_SERVICE_NAME"]),
     "erlsrv.exe" = filename:basename(
                      hd(
-                       string:tokens(
+                       string:lexemes(
                          rpc:call(make_full_name(Name),
                                   os,
                                   getenv,
diff --git a/erts/test/otp_SUITE.erl b/erts/test/otp_SUITE.erl
index 54fcfd935f..3abe45c141 100644
--- a/erts/test/otp_SUITE.erl
+++ b/erts/test/otp_SUITE.erl
@@ -336,7 +336,7 @@ not_recommended_calls(Config, Apps0, MFA) ->
                 _ ->
                     AppStrings = [atom_to_list(A) || A <- SkippedApps],
                     Mess = io_lib:format("Application(s) not present: ~s\n",
-                                         [string:join(AppStrings, ", ")]),
+                                         [lists:join(", ", AppStrings)]),
                     {comment, Mess}
             end;
         _ ->
@@ -463,7 +463,7 @@ runtime_dependencies(Config) ->
 have_rdep(_App, [], _Dep) ->
     false;
 have_rdep(App, [RDep | RDeps], Dep) ->		    
-    [AppStr, _VsnStr] = string:tokens(RDep, "-"),
+    [AppStr, _VsnStr] = string:lexemes(RDep, "-"),
     case Dep == list_to_atom(AppStr) of
         true ->
             io:format("~p -> ~s~n", [App, RDep]),
diff --git a/erts/test/run_erl_SUITE.erl b/erts/test/run_erl_SUITE.erl
index fe1ccba1e2..08edd930b4 100644
--- a/erts/test/run_erl_SUITE.erl
+++ b/erts/test/run_erl_SUITE.erl
@@ -255,7 +255,7 @@ do_run_erl(Config, Case, Opt) ->
     
     net_kernel:monitor_nodes(true),
     open_port({spawn,Cmd}, []),
-    [_,Host] = string:tokens(atom_to_list(node()), "@"),
+    [_,Host] = string:lexemes(atom_to_list(node()), "@"),
     Node = list_to_atom(NodeName++"@"++Host),
 
     receive
diff --git a/erts/test/upgrade_SUITE.erl b/erts/test/upgrade_SUITE.erl
index a5639d927d..31ceb06314 100644
--- a/erts/test/upgrade_SUITE.erl
+++ b/erts/test/upgrade_SUITE.erl
@@ -287,7 +287,7 @@ create_relfile(Node,CreateDir,RelName0,RelVsn) ->
 			 true ->
 			     case filename:split(Path) -- SplitLibDir of
 				 [AppVsn,"ebin"] ->
-				     case string:tokens(AppVsn,"-") of
+				     case string:lexemes(AppVsn,"-") of
 					 [AppStr,Vsn] ->
 					     App = list_to_atom(AppStr),
 					     case lists:member(App,Exclude) of
diff --git a/erts/test/z_SUITE.erl b/erts/test/z_SUITE.erl
index d474c71c4f..cd7a894eb5 100644
--- a/erts/test/z_SUITE.erl
+++ b/erts/test/z_SUITE.erl
@@ -132,22 +132,9 @@ core_search_conf(RunByTS, DBTop, XDir) ->
 
 file_inspect(#core_search_conf{file = File}, Core) ->
     FRes0 = os:cmd(File ++ " " ++ Core),
-    FRes = case string:str(FRes0, Core) of
-	       0 ->
-		   FRes0;
-	       S ->
-		   L = length(FRes0),
-		   E = length(Core),
-		   case S of
-		       1 ->
-			   lists:sublist(FRes0, E+1, L+1);
-		       _ ->
-			   lists:sublist(FRes0, 1, S-1)
-			       ++
-			       " "
-			       ++
-			       lists:sublist(FRes0, E+1, L+1)
-		   end
+    FRes = case string:split(FRes0, Core) of
+	       [S1] -> S1;
+	       [S1,S2] -> lists:flatten(S1 ++ " " ++ S2)
 	   end,
     case re:run(FRes, "text|ascii", [caseless,{capture,none}]) of
 	match ->
@@ -194,9 +181,6 @@ mod_time_list(F) ->
 	    [0,0,0,0,0,0]
     end.
 
-str_strip(S) ->
-    string:strip(string:strip(string:strip(S), both, $\n), both, $\r).
-
 dump_core(#core_search_conf{ cerl = false }, _) ->
     ok;
 dump_core(_, {ignore, _Core}) ->
@@ -232,7 +216,7 @@ format_core(#core_search_conf{file = false}, Core, Ignore) ->
     io:format("  ~s~s " ++ time_fstr() ++ "~s~n",
 	      [Ignore, Core] ++ mod_time_list(Core));
 format_core(#core_search_conf{file = File}, Core, Ignore) ->
-    FRes = str_strip(os:cmd(File ++ " " ++ Core)),
+    FRes = string:trim(os:cmd(File ++ " " ++ Core)),
     case catch re:run(FRes, Core, [caseless,{capture,none}]) of
 	match ->
 	    io:format("  ~s~s " ++ time_fstr() ++ "~n",
diff --git a/lib/asn1/src/asn1ct_check.erl b/lib/asn1/src/asn1ct_check.erl
index 83d12600b7..321980e5e4 100644
--- a/lib/asn1/src/asn1ct_check.erl
+++ b/lib/asn1/src/asn1ct_check.erl
@@ -1576,13 +1576,15 @@ printable_string_1(#'Externalvaluereference'{value=Type}) ->
 printable_string_1({Atom,Line}) when is_atom(Atom), is_integer(Line) ->
     q(Atom);
 printable_string_1({object,definedsyntax,L}) ->
-    q(string:join([printable_string_1(Item) || Item <- L], " "));
+    Str = lists:join($\s, [printable_string_1(Item) || Item <- L]),
+    q(lists:flatten(Str));
 printable_string_1([_|_]=Def) ->
     case lists:all(fun is_integer/1, Def) of
 	true ->
 	    lists:flatten(io_lib:format("~p", [Def]));
 	false ->
-	    q(string:join([printable_string_1(Item) || Item <- Def], " "))
+            Str = lists:join($\s, [printable_string_1(Item) || Item <- Def]),
+            q(lists:flatten(Str))
     end;
 printable_string_1(Def) ->
     lists:flatten(io_lib:format("~p", [Def])).
diff --git a/lib/asn1/src/asn1ct_gen.erl b/lib/asn1/src/asn1ct_gen.erl
index da9f6ac559..efbc6d6380 100644
--- a/lib/asn1/src/asn1ct_gen.erl
+++ b/lib/asn1/src/asn1ct_gen.erl
@@ -811,7 +811,7 @@ result_line(NoOkWrapper, Items) ->
 result_line_1([SingleItem]) ->
     SingleItem;
 result_line_1(Items) ->
-    ["{",string:join(Items, ","),"}"].
+    ["{",lists:join(",",Items),"}"].
 
 try_catch() ->
     ["  catch",nl,
@@ -958,7 +958,7 @@ open_hrl(OutFile,Module) ->
 
 hrl_protector(OutFile) ->
     BaseName = filename:basename(OutFile),
-    P = "_" ++ string:to_upper(BaseName) ++ "_HRL_",
+    P = "_" ++ string:uppercase(BaseName) ++ "_HRL_",
     [if
 	 $A =< C, C =< $Z -> C;
 	 $a =< C, C =< $a -> C;
diff --git a/lib/asn1/src/asn1rtt_real_common.erl b/lib/asn1/src/asn1rtt_real_common.erl
index 3a79209015..81c1f54d74 100644
--- a/lib/asn1/src/asn1rtt_real_common.erl
+++ b/lib/asn1/src/asn1rtt_real_common.erl
@@ -125,7 +125,7 @@ encode_real(_C, {_,Base,_}) ->
 encode_real(C, Real) when is_list(Real) ->
     %% The Real string may come in as a NR1, NR2 or NR3 string.
     {Mantissa, Exponent} =
-	case string:tokens(Real,"Ee") of
+	case string:lexemes(Real,"Ee") of
 	    [NR2] ->
 		{NR2,0};
 	    [NR3MB,NR3E] ->
@@ -144,7 +144,7 @@ encode_real(C, Real) when is_list(Real) ->
 		NewMan = remove_trailing_zeros(Dec),
 		{NewMan,length(ZeroDecimal(NewMan))};
 	    _ ->
-		case string:tokens(Mantissa,",.") of
+		case string:lexemes(Mantissa,",.") of
 		    [Num] -> %% No decimal-mark
 			{integer_to_list(list_to_integer(Num)),0};
 		    [Num,Dec] ->
diff --git a/lib/common_test/src/ct.erl b/lib/common_test/src/ct.erl
index 4c4dc8bede..69e371a30f 100644
--- a/lib/common_test/src/ct.erl
+++ b/lib/common_test/src/ct.erl
@@ -1032,7 +1032,7 @@ make_and_load(Dir, Suite) ->
     EnvInclude =
 	case os:getenv("CT_INCLUDE_PATH") of
 	    false -> [];
-	    CtInclPath -> string:tokens(CtInclPath, [$:,$ ,$,])
+	    CtInclPath -> string:lexemes(CtInclPath, [$:,$ ,$,])
 	end,
     StartInclude =
 	case init:get_argument(include) of
diff --git a/lib/common_test/src/ct_config.erl b/lib/common_test/src/ct_config.erl
index 9cb9b0ba16..6c87b11f8d 100644
--- a/lib/common_test/src/ct_config.erl
+++ b/lib/common_test/src/ct_config.erl
@@ -660,7 +660,7 @@ decrypt_config_file(EncryptFileName, TargetFileName, {key,Key}) ->
 get_crypt_key_from_file(File) ->
     case file:read_file(File) of
 	{ok,Bin} ->
-	    case catch string:tokens(binary_to_list(Bin), [$\n,$\r]) of
+	    case catch string:lexemes(binary_to_list(Bin), [$\n,$\r]) of
 		[Key] ->
 		    Key;
 		_ ->
@@ -694,7 +694,7 @@ get_crypt_key_from_file() ->
 	noent ->
 	    Result;
 	_ ->
-	    case catch string:tokens(binary_to_list(Result), [$\n,$\r]) of
+	    case catch string:lexemes(binary_to_list(Result), [$\n,$\r]) of
 		[Key] ->
 		    io:format("~nCrypt key file: ~ts~n", [FullName]),
 		    Key;
diff --git a/lib/common_test/src/ct_config_plain.erl b/lib/common_test/src/ct_config_plain.erl
index e72b55971b..e77381d7cf 100644
--- a/lib/common_test/src/ct_config_plain.erl
+++ b/lib/common_test/src/ct_config_plain.erl
@@ -106,7 +106,7 @@ read_config_terms1({done,{eof,EL},_}, L, _, _) ->
 read_config_terms1({done,{error,Info,EL},_}, L, _, _) ->
     {error,{Info,{L,EL}}};
 read_config_terms1({more,_}, L, Terms, Rest) ->
-    case string:tokens(Rest, [$\n,$\r,$\t]) of
+    case string:lexemes(Rest, [$\n,$\r,$\t]) of
 	[] ->
 	    lists:reverse(Terms);
 	_ ->
diff --git a/lib/common_test/src/ct_conn_log_h.erl b/lib/common_test/src/ct_conn_log_h.erl
index cf0a228e1b..3e83020f45 100644
--- a/lib/common_test/src/ct_conn_log_h.erl
+++ b/lib/common_test/src/ct_conn_log_h.erl
@@ -224,7 +224,7 @@ now_to_time({_,_,MicroS}=Now) ->
     {calendar:now_to_local_time(Now),MicroS}.
 
 pretty_head({{{Y,Mo,D},{H,Mi,S}},MicroS},ConnMod,Text0) ->
-    Text = string:to_upper(atom_to_list(ConnMod) ++ Text0),
+    Text = string:uppercase(atom_to_list(ConnMod) ++ Text0),
     io_lib:format("= ~s ==== ~s-~s-~w::~s:~s:~s,~s ",
 		  [Text,t(D),month(Mo),Y,t(H),t(Mi),t(S),
 		   micro2milli(MicroS)]).
@@ -275,7 +275,7 @@ pad0(N,Str) ->
     lists:duplicate(N-M,$0) ++ Str.
 
 pad_char_end(N,Str,Char) ->
-    case length(lists:flatten(Str)) of
+    case string:length(Str) of
 	M when M<N -> Str ++ lists:duplicate(N-M,Char);
 	_ -> Str
     end.
diff --git a/lib/common_test/src/ct_framework.erl b/lib/common_test/src/ct_framework.erl
index 6066470233..7f7e9ae6f9 100644
--- a/lib/common_test/src/ct_framework.erl
+++ b/lib/common_test/src/ct_framework.erl
@@ -921,9 +921,10 @@ error_notification(Mod,Func,_Args,{Error,Loc}) ->
 	      end,
     ErrorStr = case ErrorSpec of
 		 {badmatch,Descr} ->
-		     Descr1 = lists:flatten(io_lib:format("~tP",[Descr,10])),
-		     if length(Descr1) > 50 ->
-			     Descr2 = string:substr(Descr1,1,50),
+                     Descr1 = io_lib:format("~tP",[Descr,10]),
+                     DescrLength = string:length(Descr1),
+                     if DescrLength > 50 ->
+			     Descr2 = string:slice(Descr1,0,50),
 			     io_lib:format("{badmatch,~ts...}",[Descr2]);
 			true ->
 			     io_lib:format("{badmatch,~ts}",[Descr1])
diff --git a/lib/common_test/src/ct_ftp.erl b/lib/common_test/src/ct_ftp.erl
index 8effb06e7e..ee4a6a6c45 100644
--- a/lib/common_test/src/ct_ftp.erl
+++ b/lib/common_test/src/ct_ftp.erl
@@ -285,7 +285,7 @@ init(KeyOrName,{IP,Port},{Username,Password}) ->
 	{ok,FtpPid} ->
 	    log(heading(init,KeyOrName), 
 		"Opened ftp connection:\nIP: ~tp\nUsername: ~tp\nPassword: ~p\n",
-		[IP,Username,lists:duplicate(length(Password),$*)]),
+		[IP,Username,lists:duplicate(string:length(Password),$*)]),
 	    {ok,FtpPid,#state{ftp_pid=FtpPid,target_name=KeyOrName}};
 	Error ->
 	    Error
diff --git a/lib/common_test/src/ct_logs.erl b/lib/common_test/src/ct_logs.erl
index fb6a095b57..9861b1e521 100644
--- a/lib/common_test/src/ct_logs.erl
+++ b/lib/common_test/src/ct_logs.erl
@@ -1191,26 +1191,23 @@ print_style(Fd, IoFormat, StyleSheet) ->
     case file:read_file(StyleSheet) of
 	{ok,Bin} ->
 	    Str = b2s(Bin,encoding(StyleSheet)),
-	    Pos0 = case string:str(Str,"<style>") of
-		       0 -> string:str(Str,"<STYLE>");
-		       N0 -> N0
-		   end,
-	    Pos1 = case string:str(Str,"</style>") of
-		       0 -> string:str(Str,"</STYLE>");
-		       N1 -> N1
-		   end,
-	    if (Pos0 == 0) and (Pos1 /= 0) ->
-		    print_style_error(Fd, IoFormat,
-				      StyleSheet, missing_style_start_tag);
-	       (Pos0 /= 0) and (Pos1 == 0) ->
-		    print_style_error(Fd, IoFormat,
-				      StyleSheet,missing_style_end_tag);
-	       Pos0 /= 0 ->
-		    Style = string:sub_string(Str,Pos0,Pos1+7),
-		    IoFormat(Fd,"~ts\n",[Style]);
-	       Pos0 == 0 ->
-		    IoFormat(Fd,"<style>\n~ts</style>\n",[Str])
-	    end;
+            case re:run(Str,"<style>.*</style>",
+                        [dotall,caseless,{capture,all,list}]) of
+                nomatch ->
+                    case re:run(Str,"</?style>",[caseless,{capture,all,list}]) of
+                        nomatch ->
+                            IoFormat(Fd,"<style>\n~ts</style>\n",[Str]);
+                        {match,["</"++_]} ->
+                            print_style_error(Fd, IoFormat,
+                                              StyleSheet,
+                                              missing_style_start_tag);
+                        {match,[_]} ->
+                            print_style_error(Fd, IoFormat,
+                                              StyleSheet,missing_style_end_tag)
+                    end;
+                {match,[Style]} ->
+                    IoFormat(Fd,"~ts\n",[Style])
+            end;
 	{error,Reason} ->
 	    print_style_error(Fd,IoFormat,StyleSheet,Reason)
     end.
@@ -1417,9 +1414,9 @@ make_one_index_entry1(SuiteName, Link, Label, Success, Fail, UserSkip, AutoSkip,
     {Lbl,Timestamp,Node,AllInfo} =
 	case All of
 	    {true,OldRuns} -> 
-		[_Prefix,NodeOrDate|_] = string:tokens(Link,"."),
-		Node1 = case string:chr(NodeOrDate,$@) of
-			    0 -> "-";
+		[_Prefix,NodeOrDate|_] = string:lexemes(Link,"."),
+		Node1 = case string:find(NodeOrDate,[$@]) of
+			    nomatch -> "-";
 			    _ -> NodeOrDate
 			end,
 
@@ -1526,7 +1523,7 @@ not_built(BaseName,_LogDir,_All,Missing) ->
     %%            Top.ObjDir | Top.ObjDir.suites | Top.ObjDir.Suite | 
     %%            Top.ObjDir.Suite.cases | Top.ObjDir.Suite.Case    
     Failed =
-	case string:tokens(BaseName,".") of
+	case string:lexemes(BaseName,".") of
 	    [T,O] when is_list(T) ->		% all under Top.ObjDir
 		locate_info({T,O},all,Missing);
 	    [T,O,"suites"] ->
@@ -2054,9 +2051,9 @@ sort_all_runs(Dirs) ->
     %% "YYYY-MM-DD_HH.MM.SS"
     lists:sort(fun(Dir1,Dir2) ->
 		       [SS1,MM1,HH1,Date1|_] =
-			   lists:reverse(string:tokens(Dir1,[$.,$_])),
+			   lists:reverse(string:lexemes(Dir1,[$.,$_])),
 		       [SS2,MM2,HH2,Date2|_] =
-			   lists:reverse(string:tokens(Dir2,[$.,$_])),
+			   lists:reverse(string:lexemes(Dir2,[$.,$_])),
 		       {Date1,HH1,MM1,SS1} > {Date2,HH2,MM2,SS2}
 	       end, Dirs).
 
@@ -2066,9 +2063,9 @@ sort_ct_runs(Dirs) ->
     lists:sort(
       fun(Dir1,Dir2) ->
 	      [SS1,MM1,DateHH1 | _] =
-		  lists:reverse(string:tokens(filename:dirname(Dir1),[$.])),
+		  lists:reverse(string:lexemes(filename:dirname(Dir1),[$.])),
 	      [SS2,MM2,DateHH2 | _] =
-		  lists:reverse(string:tokens(filename:dirname(Dir2),[$.])),
+		  lists:reverse(string:lexemes(filename:dirname(Dir2),[$.])),
 	      {DateHH1,MM1,SS1} =< {DateHH2,MM2,SS2}
       end, Dirs).
 
@@ -2214,27 +2211,15 @@ runentry(Dir, Totals={Node,Label,Logs,
 		    0 -> "-";
 		    N -> integer_to_list(N)
 		end,
-    StripExt = 
-	fun(File) ->
-		string:sub_string(File,1,
-				  length(File)-
-				      length(?logdir_ext)) ++ ", "
-	end,
-    Polish =  fun(S) -> case lists:reverse(S) of
-			    [32,$,|Rev] -> lists:reverse(Rev);
-			    [$,|Rev] -> lists:reverse(Rev);
-			    _ -> S
-			end 
-	      end,
-    TestNames = Polish(lists:flatten(lists:map(StripExt,Logs))),
+
+    RootNames = lists:map(fun(F) -> filename:rootname(F,?logdir_ext) end, Logs),
+    TestNames = lists:flatten(lists:join(", ", RootNames)),
     TestNamesTrunc =
-	if TestNames=="" -> 
-		"";
-	   length(TestNames) < ?testname_width ->
+	if length(TestNames) < ?testname_width ->
 		TestNames;
 	   true ->
-		Trunc = Polish(string:substr(TestNames,1,
-					     ?testname_width-3)),
+		Trunc = string:trim(string:slice(TestNames,0,?testname_width-3),
+                                    trailing,",\s"),
 		lists:flatten(io_lib:format("~ts...",[Trunc]))
 	end,
     TotMissingStr =
@@ -2377,7 +2362,7 @@ force_rename(From,To,Number) ->
 
 
 timestamp(Dir) ->
-    TsR = lists:reverse(string:tokens(Dir,".-_")),
+    TsR = lists:reverse(string:lexemes(Dir,".-_")),
     [S,Min,H,D,M,Y] = [list_to_integer(N) || N <- lists:sublist(TsR,6)],
     format_time({{Y,M,D},{H,Min,S}}).
 
@@ -2926,7 +2911,7 @@ cache_vsn() ->
 	    VSNfile = filename:join([EbinDir,"..","vsn.mk"]),
 	    case file:read_file(VSNfile) of
 		{ok,Bin} ->
-		    [_,VSN] = string:tokens(binary_to_list(Bin),[$=,$\n,$ ]),
+		    [_,VSN] = string:lexemes(binary_to_list(Bin),[$=,$\n,$ ]),
 		    VSN;
 		_ ->
 		    undefined
@@ -3332,7 +3317,7 @@ insert_javascript({tablesorter,TableName,
 			  end, [{"CTDateSorter",DateCols},
 				{"CTTextSorter",TextCols},
 				{"CTValSorter",ValCols}]))),
-    Headers1 = string:substr(Headers, 1, length(Headers)-2),
+    Headers1 = string:trim(Headers, trailing, ",\n"),
 
     ["<script type=\"text/javascript\">\n",
      "// Parser for date format, e.g: Wed Jul 4 2012 11:24:15\n",
diff --git a/lib/common_test/src/ct_master.erl b/lib/common_test/src/ct_master.erl
index ef2aff69b7..e2ea525cdd 100644
--- a/lib/common_test/src/ct_master.erl
+++ b/lib/common_test/src/ct_master.erl
@@ -809,7 +809,7 @@ filter_accessible(InitOptions, Inaccessible)->
 
 start_nodes(InitOptions)->
     lists:foreach(fun({NodeName, Options})->
-	[NodeS,HostS]=string:tokens(atom_to_list(NodeName), "@"),
+	[NodeS,HostS]=string:lexemes(atom_to_list(NodeName), "@"),
 	Node=list_to_atom(NodeS),
 	Host=list_to_atom(HostS),
 	HasNodeStart = lists:keymember(node_start, 1, Options),
diff --git a/lib/common_test/src/ct_master_logs.erl b/lib/common_test/src/ct_master_logs.erl
index c4bb2cc69f..1308720823 100644
--- a/lib/common_test/src/ct_master_logs.erl
+++ b/lib/common_test/src/ct_master_logs.erl
@@ -298,7 +298,7 @@ sort_all_runs(Dirs) ->
     %% "YYYY-MM-DD_HH.MM.SS"
     KeyList =
 	lists:map(fun(Dir) ->
-			  case lists:reverse(string:tokens(Dir,[$.,$_])) of
+			  case lists:reverse(string:lexemes(Dir,[$.,$_])) of
 			      [SS,MM,HH,Date|_] ->
 				  {{Date,HH,MM,SS},Dir};
 			      _Other ->
@@ -313,18 +313,8 @@ runentry(Dir) ->
     {MasterStr,NodesStr} = 
 	case read_details_file(Dir) of
 	    {Master,Nodes} when is_list(Nodes) ->
-		[_,Host] = string:tokens(atom_to_list(Master),"@"),
-		NodesList = 
-		    lists:reverse(lists:map(fun(N) ->
-						    atom_to_list(N) ++ ", "
-					    end,Nodes)),
-		case NodesList of
-		    [N|NListR] ->
-			N1 = string:sub_string(N,1,length(N)-2),
-			{Host,lists:flatten(lists:reverse([N1|NListR]))};
-		    [] ->
-			{Host,""}
-		end;
+		[_,Host] = string:lexemes(atom_to_list(Master),"@"),
+                {Host,lists:concat(lists:join(", ",Nodes))};
 	    _Error ->
 		{"unknown",""}
 	end,
@@ -349,7 +339,7 @@ all_runs_header() ->
       xhtml("", "</tr></thead>\n<tbody>\n")]].
 
 timestamp(Dir) ->
-    [S,Min,H,D,M,Y|_] = lists:reverse(string:tokens(Dir,".-_")),
+    [S,Min,H,D,M,Y|_] = lists:reverse(string:lexemes(Dir,".-_")),
     [S1,Min1,H1,D1,M1,Y1] = [list_to_integer(N) || N <- [S,Min,H,D,M,Y]],
     format_time({{Y1,M1,D1},{H1,Min1,S1}}).
 
diff --git a/lib/common_test/src/ct_netconfc.erl b/lib/common_test/src/ct_netconfc.erl
index 2c4b97df20..29188a648e 100644
--- a/lib/common_test/src/ct_netconfc.erl
+++ b/lib/common_test/src/ct_netconfc.erl
@@ -1467,7 +1467,7 @@ decode_data(Other) ->
     {error,{unexpected_rpc_reply,Other}}.
 
 get_qualified_name(Tag) ->
-    case string:tokens(atom_to_list(Tag),":") of
+    case string:lexemes(atom_to_list(Tag),":") of
 	[TagStr] -> {[],TagStr};
 	[PrefixStr,TagStr] -> {PrefixStr,TagStr}
     end.
diff --git a/lib/common_test/src/ct_release_test.erl b/lib/common_test/src/ct_release_test.erl
index 551a7e06d7..4af9afb45b 100644
--- a/lib/common_test/src/ct_release_test.erl
+++ b/lib/common_test/src/ct_release_test.erl
@@ -817,7 +817,7 @@ get_runtime_deps([App|Apps],StartApps,Acc,Visited) ->
 	    RuntimeDeps =
 		lists:flatmap(
 		  fun(Str) ->
-			  [RuntimeAppStr,_] = string:tokens(Str,"-"),
+			  [RuntimeAppStr,_] = string:lexemes(Str,"-"),
 			  RuntimeApp = list_to_atom(RuntimeAppStr),
 			  case {lists:keymember(RuntimeApp,1,Acc),
 				lists:member(RuntimeApp,StartApps)} of
diff --git a/lib/common_test/src/ct_run.erl b/lib/common_test/src/ct_run.erl
index 05b1e70098..8c401cf3f5 100644
--- a/lib/common_test/src/ct_run.erl
+++ b/lib/common_test/src/ct_run.erl
@@ -147,7 +147,7 @@ script_start(Args) ->
 	    CTVsn =
 		case filename:basename(code:lib_dir(common_test)) of
 		    CTBase when is_list(CTBase) ->
-			case string:tokens(CTBase, "-") of
+			case string:lexemes(CTBase, "-") of
 			    ["common_test",Vsn] -> " v"++Vsn;
 			    _ -> ""
 			end
@@ -317,7 +317,7 @@ script_start1(Parent, Args) ->
 			{undefined,InclDirs};
 		    CtInclPath ->
 			AllInclDirs =
-			    string:tokens(CtInclPath,[$:,$ ,$,]) ++ InclDirs,
+			    string:lexemes(CtInclPath,[$:,$ ,$,]) ++ InclDirs,
 			application:set_env(common_test, include, AllInclDirs),
 			{undefined,AllInclDirs}
 		end;
@@ -1101,7 +1101,7 @@ run_test2(StartOpts) ->
 			application:set_env(common_test, include, InclDirs),
 			{undefined,InclDirs};
 		    CtInclPath ->
-			InclDirs1 = string:tokens(CtInclPath, [$:,$ ,$,]),
+			InclDirs1 = string:lexemes(CtInclPath, [$:,$ ,$,]),
 			AllInclDirs = InclDirs1++InclDirs,
 			application:set_env(common_test, include, AllInclDirs),
 			{undefined,AllInclDirs}
@@ -1490,7 +1490,7 @@ run_testspec2(TestSpec) ->
 		    false ->
 			Opts#opts.include;
 		    CtInclPath ->
-			EnvInclude = string:tokens(CtInclPath, [$:,$ ,$,]),
+			EnvInclude = string:lexemes(CtInclPath, [$:,$ ,$,]),
 			EnvInclude++Opts#opts.include
 		end,
 	    application:set_env(common_test, include, AllInclude),
diff --git a/lib/common_test/src/ct_slave.erl b/lib/common_test/src/ct_slave.erl
index b39195483b..0c16ad5980 100644
--- a/lib/common_test/src/ct_slave.erl
+++ b/lib/common_test/src/ct_slave.erl
@@ -38,7 +38,8 @@
 
 -record(options, {username, password, boot_timeout, init_timeout,
 		  startup_timeout, startup_functions, monitor_master,
-		  kill_if_fail, erl_flags, env, ssh_port, ssh_opts}).
+		  kill_if_fail, erl_flags, env, ssh_port, ssh_opts,
+		  stop_timeout}).
 
 %%%-----------------------------------------------------------------
 %%% @spec start(Node) -> Result
@@ -198,6 +199,7 @@ start(Host, Node, Opts) ->
 	    end
     end.
 
+%%%-----------------------------------------------------------------
 %%% @spec stop(Node) -> Result
 %%%   Node = atom()
 %%%   Result = {ok, NodeName} |
@@ -205,16 +207,41 @@ start(Host, Node, Opts) ->
 %%%   Reason = not_started |
 %%%            not_connected |
 %%%            stop_timeout
-
 %%%   NodeName = atom()
 %%% @doc Stops the running Erlang node with name <code>Node</code> on
 %%% the localhost.
 stop(Node) ->
     stop(gethostname(), Node).
 
-%%% @spec stop(Host, Node) -> Result
+%%%-----------------------------------------------------------------
+%%% @spec stop(HostOrNode, NodeOrOpts) -> Result
+%%%   HostOrNode = atom()
+%%%   NodeOrOpts = atom() | list()
+%%%   Result = {ok, NodeName} |
+%%%            {error, Reason, NodeName}
+%%%   Reason = not_started |
+%%%            not_connected |
+%%%            stop_timeout
+%%%   NodeName = atom()
+%%% @doc Stops the running Erlang node with default options on a specified
+%%% host, or on the local host with specified options. That is,
+%%% the call is interpreted as <code>stop(Host, Node)</code> when the
+%%% second argument is atom-valued and <code>stop(Node, Opts)</code>
+%%% when it's list-valued.
+%%% @see stop/3
+stop(_HostOrNode = Node, _NodeOrOpts = Opts) %% match to satiate edoc
+  when is_list(Opts) ->
+    stop(gethostname(), Node, Opts);
+
+stop(Host, Node) ->
+    stop(Host, Node, []).
+
+%%% @spec stop(Host, Node, Opts) -> Result
 %%%   Host = atom()
 %%%   Node = atom()
+%%%   Opts = [OptTuples]
+%%%   OptTuples = {stop_timeout, StopTimeout}
+%%%   StopTimeout = integer()
 %%%   Result = {ok, NodeName} |
 %%%            {error, Reason, NodeName}
 %%%   Reason = not_started |
@@ -222,12 +249,19 @@ stop(Node) ->
 %%%            stop_timeout
 %%%   NodeName = atom()
 %%% @doc Stops the running Erlang node with name <code>Node</code> on
-%%% host <code>Host</code>.
-stop(Host, Node) ->
+%%% host <code>Host</code> as specified by options <code>Opts</code>.
+%%%
+%%% <p>Option <code>stop_timeout</code> specifies, in seconds,
+%%% the time to wait until the node is disconnected.
+%%% Defaults to 5 seconds. If this timeout occurs,
+%%% the result <code>{error, stop_timeout, NodeName}</code> is returned.
+%%%
+stop(Host, Node, Opts) ->
     ENode = enodename(Host, Node),
     case is_started(ENode) of
 	{true, connected}->
-	     do_stop(ENode);
+	     OptionsRec = fetch_options(Opts),
+	     do_stop(ENode, OptionsRec);
 	{true, not_connected}->
 	     {error, not_connected, ENode};
 	false->
@@ -257,11 +291,13 @@ fetch_options(Options) ->
     EnvVars = get_option_value(env, Options, []),
     SSHPort = get_option_value(ssh_port, Options, []),
     SSHOpts = get_option_value(ssh_opts, Options, []),
+    StopTimeout = get_option_value(stop_timeout, Options, 5),
     #options{username=UserName, password=Password,
 	     boot_timeout=BootTimeout, init_timeout=InitTimeout,
 	     startup_timeout=StartupTimeout, startup_functions=StartupFunctions,
 	     monitor_master=Monitor, kill_if_fail=KillIfFail,
-	     erl_flags=ErlFlags, env=EnvVars, ssh_port=SSHPort, ssh_opts=SSHOpts}.
+	     erl_flags=ErlFlags, env=EnvVars, ssh_port=SSHPort, ssh_opts=SSHOpts,
+	     stop_timeout=StopTimeout}.
 
 % send a message when slave node is started
 % @hidden
@@ -462,6 +498,8 @@ wait_for_node_alive(Node, N) ->
 
 % call init:stop on a remote node
 do_stop(ENode) ->
+    do_stop(ENode, fetch_options([])).
+do_stop(ENode, Options) ->
     {Cover,MainCoverNode} =
 	case test_server:is_cover() of
 	    true ->
@@ -472,7 +510,8 @@ do_stop(ENode) ->
 		{false,undefined}
     end,
     spawn(ENode, init, stop, []),
-    case wait_for_node_dead(ENode, 5) of
+    StopTimeout = Options#options.stop_timeout,
+    case wait_for_node_dead(ENode, StopTimeout) of
 	{ok,ENode} ->
 	    if Cover ->
 		    %% To avoid that cover is started again if a node
diff --git a/lib/common_test/src/ct_ssh.erl b/lib/common_test/src/ct_ssh.erl
index ca62357e1c..491d56dfc1 100644
--- a/lib/common_test/src/ct_ssh.erl
+++ b/lib/common_test/src/ct_ssh.erl
@@ -996,7 +996,8 @@ init(KeyOrName, {ConnType,Addr,Port}, AllOpts) ->
 	    try_log(heading(init,KeyOrName), 
 		    "Opened ~w connection:\n"
 		    "Host: ~tp (~p)\nUser: ~tp\nPassword: ~p\n",
-		[ConnType,Addr,Port,User,lists:duplicate(length(Password),$*)]),
+		[ConnType,Addr,Port,User,
+                 lists:duplicate(string:length(Password),$*)]),
 	    {ok,SSHRef,#state{ssh_ref=SSHRef, conn_type=ConnType,
 			      target=KeyOrName}}
     end.
diff --git a/lib/common_test/src/ct_util.erl b/lib/common_test/src/ct_util.erl
index 468edc4bee..10a06d5c88 100644
--- a/lib/common_test/src/ct_util.erl
+++ b/lib/common_test/src/ct_util.erl
@@ -799,25 +799,25 @@ parse_table(Data) ->
     {Heading,Lines}.
 
 get_headings(["|" ++ Headings | Rest]) ->
-    {remove_space(string:tokens(Headings, "|"),[]), Rest};
+    {remove_space(string:lexemes(Headings, "|"),[]), Rest};
 get_headings([_ | Rest]) ->
     get_headings(Rest);
 get_headings([]) ->
     {{},[]}.
 
 parse_row(["|" ++ _ = Row | T], Rows, NumCols) when NumCols > 1 ->
-    case string:tokens(Row, "|") of
+    case string:lexemes(Row, "|") of
 	Values when length(Values) =:= NumCols ->
 	    parse_row(T,[remove_space(Values,[])|Rows], NumCols);
 	Values when length(Values) < NumCols ->
 	    parse_row([Row ++"\n"++ hd(T) | tl(T)], Rows, NumCols)
     end;
-parse_row(["|" ++ _ = Row | T], Rows, 1 = NumCols) ->
-    case string:rchr(Row, $|) of
-	1 ->
+parse_row(["|" ++ X = Row | T], Rows, 1 = NumCols) ->
+    case string:find(X, [$|]) of
+	nomatch ->
 	    parse_row([Row ++"\n"++hd(T) | tl(T)], Rows, NumCols);
 	_Else ->
-	    parse_row(T, [remove_space(string:tokens(Row,"|"),[])|Rows],
+	    parse_row(T, [remove_space(string:lexemes(Row,"|"),[])|Rows],
 		      NumCols)
     end;
 parse_row([_Skip | T], Rows, NumCols) ->
@@ -826,7 +826,7 @@ parse_row([], Rows, _NumCols) ->
     lists:reverse(Rows).
 
 remove_space([Str|Rest],Acc) ->
-    remove_space(Rest,[string:strip(string:strip(Str),both,$')|Acc]);
+    remove_space(Rest,[string:trim(string:trim(Str,both,[$\s]),both,[$'])|Acc]);
 remove_space([],Acc) ->
     list_to_tuple(lists:reverse(Acc)).
 
@@ -836,7 +836,7 @@ remove_space([],Acc) ->
 %%%
 %%% @doc
 is_test_dir(Dir) ->
-    lists:last(string:tokens(filename:basename(Dir), "_")) == "test".
+    lists:last(string:lexemes(filename:basename(Dir), "_")) == "test".
 
 %%%-----------------------------------------------------------------
 %%% @spec 
@@ -1145,7 +1145,7 @@ open_url(iexplore, Args, URL) ->
     _ = case win32reg:values(R) of
 	{ok, Paths} ->
 	    Path = proplists:get_value(default, Paths),
-	    [Cmd | _] = string:tokens(Path, "%"),
+	    [Cmd | _] = string:lexemes(Path, "%"),
 	    Cmd1 = Cmd ++ " " ++ Args ++ " " ++ URL,
 	    io:format(?def_gl, "~nOpening ~ts with command:~n  ~ts~n", [URL,Cmd1]),
 	    open_port({spawn,Cmd1}, []);
diff --git a/lib/common_test/src/cth_log_redirect.erl b/lib/common_test/src/cth_log_redirect.erl
index 77f90c0df6..b05f0bd28b 100644
--- a/lib/common_test/src/cth_log_redirect.erl
+++ b/lib/common_test/src/cth_log_redirect.erl
@@ -122,8 +122,8 @@ handle_event({_Type,GL,_Msg}, #eh_state{handle_remote_events = false} = State)
   when node(GL) /= node() ->
     {ok, State};
 handle_event(Event, #eh_state{log_func = LogFunc} = State) ->
-    case lists:keyfind(sasl, 1, application:which_applications()) of
-	false ->
+    case whereis(sasl_sup) of
+	undefined ->
 	    sasl_not_started;
 	_Else ->
 	    {ok, ErrLogType} = application:get_env(sasl, errlog_type),
diff --git a/lib/common_test/src/cth_surefire.erl b/lib/common_test/src/cth_surefire.erl
index da68bd105e..4407ff56c1 100644
--- a/lib/common_test/src/cth_surefire.erl
+++ b/lib/common_test/src/cth_surefire.erl
@@ -184,15 +184,14 @@ end_tc(Name, _Config, _Res, State = #state{ curr_suite = Suite,
     Log =
 	case Log0 of
 	    "" ->
-		LowerSuiteName = string:to_lower(atom_to_list(Suite)),
+		LowerSuiteName = string:lowercase(atom_to_list(Suite)),
 		filename:join(CurrLogDir,LowerSuiteName++"."++Name++".html");
 	    _ ->
 		Log0
 	end,
     Url = make_url(UrlBase,Log),
     ClassName = atom_to_list(Suite),
-    PGroup = string:join([ atom_to_list(Group)||
-			     Group <- lists:reverse(Groups)],"."),
+    PGroup = lists:concat(lists:join(".",lists:reverse(Groups))),
     TimeTakes = io_lib:format("~f",[timer:now_diff(?now,TS) / 1000000]),
     State#state{ test_cases = [#testcase{ log = Log,
 					  url = Url,
@@ -317,9 +316,9 @@ make_url(undefined,_) ->
 make_url(_,[]) ->
     undefined;
 make_url(UrlBase0,Log) ->
-    UrlBase = string:strip(UrlBase0,right,$/),
+    UrlBase = string:trim(UrlBase0,trailing,[$/]),
     RelativeLog = get_relative_log_url(Log),
-    string:join([UrlBase,RelativeLog],"/").
+    lists:flatten(lists:join($/,[UrlBase,RelativeLog])).
 
 get_test_root(Log) ->
     LogParts = filename:split(Log),
@@ -329,7 +328,7 @@ get_relative_log_url(Log) ->
     LogParts = filename:split(Log),
     Start = length(LogParts)-?log_depth,
     Length = ?log_depth+1,
-    string:join(lists:sublist(LogParts,Start,Length),"/").
+    lists:flatten(lists:join($/,lists:sublist(LogParts,Start,Length))).
 
 count_tcs([#testcase{name=ConfCase}|TCs],Ok,F,S)
   when ConfCase=="init_per_suite";
diff --git a/lib/common_test/src/test_server.erl b/lib/common_test/src/test_server.erl
index e56106408f..7250041e13 100644
--- a/lib/common_test/src/test_server.erl
+++ b/lib/common_test/src/test_server.erl
@@ -463,11 +463,12 @@ run_test_case_msgloop(#st{ref=Ref,pid=Pid,end_conf_pid=EndConfPid0}=St0) ->
 			 %% it as a comment, potentially replacing user data
 			 Error = lists:flatten(io_lib:format("Aborted: ~tp",
 							     [Reason])),
-			 Error1 = lists:flatten([string:strip(S,left) ||
-						    S <- string:tokens(Error,
-								       [$\n])]),
-			 Comment = if length(Error1) > 63 ->
-					   string:substr(Error1,1,60) ++ "...";
+			 Error1 = lists:flatten([string:trim(S,leading,"\s") ||
+						    S <- string:lexemes(Error,
+                                                                        [$\n])]),
+                         ErrorLength = string:length(Error1),
+			 Comment = if ErrorLength > 63 ->
+					   string:slice(Error1,0,60) ++ "...";
 				      true ->
 					   Error1
 				   end,
@@ -2707,9 +2708,9 @@ is_cover() ->
 is_debug() ->
     case catch erlang:system_info(debug_compiled) of
 	{'EXIT', _} ->
-	    case string:str(erlang:system_info(system_version), "debug") of
-		Int when is_integer(Int), Int > 0 -> true;
-		_ -> false
+	    case string:find(erlang:system_info(system_version), "debug") of
+                nomatch -> false;
+		_ -> true
 	    end;
 	Res ->
 	    Res
@@ -2745,9 +2746,9 @@ has_superfluous_schedulers() ->
 %% We might want to do more tests on a commercial platform, for instance
 %% ensuring that all applications have documentation).
 is_commercial() ->
-    case string:str(erlang:system_info(system_version), "source") of
-	Int when is_integer(Int), Int > 0 -> false;
-	_ -> true
+    case string:find(erlang:system_info(system_version), "source") of
+        nomatch -> true;
+	_ -> false
     end.
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
diff --git a/lib/common_test/src/test_server_ctrl.erl b/lib/common_test/src/test_server_ctrl.erl
index 8ef28b3343..3a454a1e84 100644
--- a/lib/common_test/src/test_server_ctrl.erl
+++ b/lib/common_test/src/test_server_ctrl.erl
@@ -1472,13 +1472,14 @@ get_suites([], Mods) ->
     lists:reverse(Mods).
 
 add_mod(Mod, Mods) ->
-    case string:rstr(atom_to_list(Mod), "_SUITE") of
-	0 -> false;
-	_ ->					% test suite
+    case lists:reverse(atom_to_list(Mod)) of
+        "ETIUS_" ++ _ -> % test suite
 	     case lists:member(Mod, Mods) of
 		 true ->  false;
 		 false -> true
-	     end
+	     end;
+        _ ->
+            false
     end.
 
 
@@ -2632,7 +2633,7 @@ run_test_cases_loop([{conf,Ref,Props,{Mod,Func}}|_Cases]=Cs0,
 				NumStr ->
 				    %% Ex: "123 456 789" or "123,456,789" -> {123,456,789}
 				    list_to_tuple([list_to_integer(NS) ||
-						   NS <- string:tokens(NumStr, [$ ,$:,$,])])
+						   NS <- string:lexemes(NumStr, [$ ,$:,$,])])
 			    end,
 			{shuffle_cases(Ref, Cs0, UseSeed),{shuffle,UseSeed}}
 		end;
@@ -4001,11 +4002,12 @@ progress(skip, CaseNum, Mod, Func, GrName, Loc, Reason, Time,
 			       true -> "~w"
 			    end, [Time]),
     ReasonStr = escape_chars(reason_to_string(Reason1)),
-    ReasonStr1 = lists:flatten([string:strip(S,left) ||
-				S <- string:tokens(ReasonStr,[$\n])]),
+    ReasonStr1 = lists:flatten([string:trim(S,leading,"\s") ||
+				S <- string:lexemes(ReasonStr,[$\n])]),
+    ReasonLength = string:length(ReasonStr1),
     ReasonStr2 =
-	if length(ReasonStr1) > 80 ->
-		string:substr(ReasonStr1, 1, 77) ++ "...";
+	if ReasonLength > 80 ->
+		string:slice(ReasonStr1, 0, 77) ++ "...";
 	   true ->
 		ReasonStr1
 	end,
@@ -4089,11 +4091,12 @@ progress(failed, CaseNum, Mod, Func, GrName, unknown, Reason, Time,
 			       true -> "~w"
 			    end, [Time]),
     ErrorReason = escape_chars(lists:flatten(io_lib:format("~tp", [Reason]))),
-    ErrorReason1 = lists:flatten([string:strip(S,left) ||
-				  S <- string:tokens(ErrorReason,[$\n])]),
+    ErrorReason1 = lists:flatten([string:trim(S,leading,"\s") ||
+				  S <- string:lexemes(ErrorReason,[$\n])]),
+    ErrorReasonLength = string:length(ErrorReason1),
     ErrorReason2 =
-	if length(ErrorReason1) > 63 ->
-		string:substr(ErrorReason1, 1, 60) ++ "...";
+	if ErrorReasonLength > 63 ->
+		string:slice(ErrorReason1, 0, 60) ++ "...";
 	   true ->
 		ErrorReason1
 	end,
diff --git a/lib/common_test/src/test_server_node.erl b/lib/common_test/src/test_server_node.erl
index b3b6ae3d92..b2d4f199c3 100644
--- a/lib/common_test/src/test_server_node.erl
+++ b/lib/common_test/src/test_server_node.erl
@@ -315,9 +315,11 @@ start_node_peer(SlaveName, OptList, From, TI) ->
     Prog0 = start_node_get_option_value(erl, OptList, default),
     Prog = quote_progname(pick_erl_program(Prog0)),
     Args = 
-	case string:str(SuppliedArgs,"-setcookie") of
-	    0 -> "-setcookie " ++ TI#target_info.cookie ++ " " ++ SuppliedArgs;
-	    _ -> SuppliedArgs
+	case string:find(SuppliedArgs,"-setcookie") of
+	    nomatch ->
+                "-setcookie " ++ TI#target_info.cookie ++ " " ++ SuppliedArgs;
+	    _ ->
+                SuppliedArgs
 	end,
     Cmd = lists:concat([Prog,
 			" -detached ",
@@ -612,7 +614,7 @@ pick_erl_program(L) ->
 %% emulator and flags as the test node. The return from lib:progname()
 %% could then typically be '/<full_path_to>/cerl -gcov').
 quote_progname(Progname) ->
-    do_quote_progname(string:tokens(Progname," ")).
+    do_quote_progname(string:lexemes(Progname," ")).
 
 do_quote_progname([Prog]) ->
     "\""++Prog++"\"";
diff --git a/lib/common_test/src/unix_telnet.erl b/lib/common_test/src/unix_telnet.erl
index 8ac467014c..5992f26e6d 100644
--- a/lib/common_test/src/unix_telnet.erl
+++ b/lib/common_test/src/unix_telnet.erl
@@ -121,7 +121,8 @@ connect1(Name,Ip,Port,Timeout,KeepAlive,TCPNoDelay,Username,Password) ->
 							  prompt,?prx,[]) of
 			    {ok,{prompt,?password},_} ->
 				ok = ct_telnet_client:send_data(Pid,Password),
-				Stars = lists:duplicate(length(Password),$*),
+				Stars =
+                                    lists:duplicate(string:length(Password),$*),
 				log(Name,send,"Password: ~s",[Stars]),
 %				ok = ct_telnet_client:send_data(Pid,""),
 				case ct_telnet:silent_teln_expect(Name,Pid,[],
diff --git a/lib/common_test/test/ct_config_SUITE.erl b/lib/common_test/test/ct_config_SUITE.erl
index 250700741c..5ffc735d6a 100644
--- a/lib/common_test/test/ct_config_SUITE.erl
+++ b/lib/common_test/test/ct_config_SUITE.erl
@@ -213,8 +213,8 @@ reformat_events(Events, EH) ->
 skip_dynamic() ->
     case os:getenv("TS_EXTRA_PLATFORM_LABEL") of
 	TSExtraPlatformLabel when is_list(TSExtraPlatformLabel) ->
-	    case string:str(TSExtraPlatformLabel,"TimeWarpingOS") of
-		0 -> false;
+	    case string:find(TSExtraPlatformLabel,"TimeWarpingOS") of
+		nomatch -> false;
 		_ -> true
 	    end;
 	_ ->
diff --git a/lib/common_test/test/ct_hooks_SUITE.erl b/lib/common_test/test/ct_hooks_SUITE.erl
index 8ba14e63bc..3c1e887f65 100644
--- a/lib/common_test/test/ct_hooks_SUITE.erl
+++ b/lib/common_test/test/ct_hooks_SUITE.erl
@@ -257,7 +257,7 @@ cth_log(Config) when is_list(Config) ->
     lists:foreach(
       fun(UnexpIoLog) ->
 	      {ok,Bin} = file:read_file(UnexpIoLog),
-	      Ts = string:tokens(binary_to_list(Bin),[$\n]),
+	      Ts = string:lexemes(binary_to_list(Bin),[$\n]),
 	      Matches = lists:foldl(fun([$=,$E,$R,$R,$O,$R|_],  N) ->
 					    N+1;
 				       ([$L,$o,$g,$g,$e,$r|_],  N) ->
diff --git a/lib/common_test/test/ct_log_SUITE.erl b/lib/common_test/test/ct_log_SUITE.erl
index 93affda398..9655b6f09a 100644
--- a/lib/common_test/test/ct_log_SUITE.erl
+++ b/lib/common_test/test/ct_log_SUITE.erl
@@ -174,7 +174,7 @@ verify(Config) ->
     TcLogFile = proplists:get_value(the_logfile, SavedCfg),
     Pid = proplists:get_value(the_pid, SavedCfg),
     StrPid = lists:flatten(io_lib:format("~p",[Pid])),
-    EscPid = "&lt;" ++ string:substr(StrPid, 2, length(StrPid)-2) ++ "&gt;", 
+    EscPid = "&lt;" ++ string:slice(StrPid, 1, length(StrPid)-2) ++ "&gt;", 
     String = proplists:get_value(the_string, SavedCfg),
     ct:log("Read from prev testcase: ~p & ~p", [TcLogFile,Pid]),
     {ok,Dev} = file:open(TcLogFile, [read]),
diff --git a/lib/common_test/test/ct_pre_post_test_io_SUITE.erl b/lib/common_test/test/ct_pre_post_test_io_SUITE.erl
index 7ffe6f045b..0b85392009 100644
--- a/lib/common_test/test/ct_pre_post_test_io_SUITE.erl
+++ b/lib/common_test/test/ct_pre_post_test_io_SUITE.erl
@@ -164,7 +164,7 @@ pre_post_io(Config) ->
       fun(PrePostIoFile) ->
 	      ct:log("Reading Pre/Post Test IO Log file: ~ts", [PrePostIoFile]),
 	      {ok,Bin} = file:read_file(PrePostIoFile),
-	      Ts = string:tokens(binary_to_list(Bin),[$\n]),
+	      Ts = string:lexemes(binary_to_list(Bin),[$\n]),
 	      PrePostIOEntries =
 		  lists:foldl(fun([$L,$o,$g,$g,$e,$r|_],
 				  {pre,PreLogN,PreErrN,0,0}) ->
@@ -203,7 +203,7 @@ pre_post_io(Config) ->
       fun(UnexpIoFile) ->
 	      ct:log("Reading Unexpected IO Log file: ~ts", [UnexpIoFile]),
 	      {ok,Bin} = file:read_file(UnexpIoFile),
-	      Ts = string:tokens(binary_to_list(Bin),[$\n]),
+	      Ts = string:lexemes(binary_to_list(Bin),[$\n]),
 	      UnexpIOEntries =
 		  lists:foldl(fun([$L,$o,$g,$g,$e,$r|_], [LogN,ErrN]) ->
 				      [LogN+1,ErrN];
diff --git a/lib/common_test/test/ct_priv_dir_SUITE_data/priv_dir_SUITE.erl b/lib/common_test/test/ct_priv_dir_SUITE_data/priv_dir_SUITE.erl
index 1b171801a3..b1d191873d 100644
--- a/lib/common_test/test/ct_priv_dir_SUITE_data/priv_dir_SUITE.erl
+++ b/lib/common_test/test/ct_priv_dir_SUITE_data/priv_dir_SUITE.erl
@@ -126,12 +126,12 @@ default(Config) ->
 
 auto_per_tc(Config) ->
     PrivDir = proplists:get_value(priv_dir, Config),
-    ["log_private",_] = string:tokens(filename:basename(PrivDir), "."),
+    ["log_private",_] = string:lexemes(filename:basename(PrivDir), "."),
     {ok,_} = file:list_dir(PrivDir).
 
 manual_per_tc(Config) ->
     PrivDir = proplists:get_value(priv_dir, Config),
-    ["log_private",_] = string:tokens(filename:basename(PrivDir), "."),
+    ["log_private",_] = string:lexemes(filename:basename(PrivDir), "."),
     {error,_} = file:list_dir(PrivDir),
     ok = ct:make_priv_dir(),
     {ok,_} = file:list_dir(PrivDir).
diff --git a/lib/common_test/test/ct_test_support.erl b/lib/common_test/test/ct_test_support.erl
index 44c27e54c2..2ba7c7c13f 100644
--- a/lib/common_test/test/ct_test_support.erl
+++ b/lib/common_test/test/ct_test_support.erl
@@ -88,7 +88,7 @@ start_slave(Config, Level) ->
     start_slave(ct, Config, Level).
 
 start_slave(NodeName, Config, Level) ->
-    [_,Host] = string:tokens(atom_to_list(node()), "@"),
+    [_,Host] = string:lexemes(atom_to_list(node()), "@"),
     test_server:format(0, "Trying to start ~s~n",
 		       [atom_to_list(NodeName)++"@"++Host]),
     PR = proplists:get_value(printable_range,Config,io:printable_range()),
@@ -1088,8 +1088,8 @@ locate({TEH,Name,{'DEF','RUNDIR'}}, Node, [Ev|Evs], Config) ->
 	{TEH,#event{name=Name, node=Node, data=EvData}} ->
 	    {_,{_,LogDir}} = lists:keysearch(logdir, 1, get_opts(Config)),
 	    D = filename:join(LogDir, "ct_run." ++ atom_to_list(Node)),
-	    case string:str(EvData, D) of
-		0 -> exit({badmatch,EvData});
+	    case string:find(EvData, D) of
+		nomatch -> exit({badmatch,EvData});
 		_ -> ok	    
 	    end,
 	    {Config,Evs};
@@ -1104,8 +1104,8 @@ locate({TEH,Name,{'DEF',{'START_TIME','LOGDIR'}}}, Node, [Ev|Evs], Config) ->
 		{DT={{_,_,_},{_,_,_}},Dir} when is_list(Dir) ->
 		    {_,{_,LogDir}} = lists:keysearch(logdir, 1, get_opts(Config)),
 		    D = filename:join(LogDir, "ct_run." ++ atom_to_list(Node)),
-		    case string:str(Dir, D) of
-			0 -> exit({badmatch,Dir});
+		    case string:find(Dir, D) of
+			nomatch -> exit({badmatch,Dir});
 			_ -> ok	    
 		    end,
 		    {[{start_time,DT}|Config],Evs};
@@ -1373,7 +1373,7 @@ delete_dirs(LogDir) ->
     Dirs2Del =
 	lists:foldl(fun(Dir, Del) ->
 			    [S,Mi,H,D,Mo,Y|_] = 
-				lists:reverse(string:tokens(Dir, [$.,$-,$_])),
+				lists:reverse(string:lexemes(Dir, [$.,$-,$_])),
 			    S2I = fun(Str) -> list_to_integer(Str) end,
 			    DT = {{S2I(Y),S2I(Mo),S2I(D)}, {S2I(H),S2I(Mi),S2I(S)}},
 			    Then = calendar:datetime_to_gregorian_seconds(DT),
diff --git a/lib/common_test/test/ct_unicode_SUITE.erl b/lib/common_test/test/ct_unicode_SUITE.erl
index 355503a5dc..6f6ec97ceb 100644
--- a/lib/common_test/test/ct_unicode_SUITE.erl
+++ b/lib/common_test/test/ct_unicode_SUITE.erl
@@ -191,7 +191,7 @@ check_logs(Dirs) ->
         [] ->
             ok;
         Match ->
-            MatchStr = string:join(Match,"\n"),
+            MatchStr = lists:join("\n",Match),
             ct:log("ERROR: Escaped unicode characters found in:~n~ts",[MatchStr]),
             ct:fail(escaped_unicode_characters_found)
     end.
diff --git a/lib/common_test/test/ct_userconfig_callback.erl b/lib/common_test/test/ct_userconfig_callback.erl
index c723f4ca1c..14e3d9a688 100644
--- a/lib/common_test/test/ct_userconfig_callback.erl
+++ b/lib/common_test/test/ct_userconfig_callback.erl
@@ -21,7 +21,7 @@
 -export([check_parameter/1, read_config/1]).
 
 read_config(Str) ->
-    KeyVals = string:tokens(Str, " "),
+    KeyVals = string:lexemes(Str, " "),
     {ok,read_config1(KeyVals)}.
 
 read_config1([Key,Val | KeyVals]) ->
diff --git a/lib/common_test/test/erl2html2_SUITE.erl b/lib/common_test/test/erl2html2_SUITE.erl
index 53a63578b2..b2336ff0bc 100644
--- a/lib/common_test/test/erl2html2_SUITE.erl
+++ b/lib/common_test/test/erl2html2_SUITE.erl
@@ -214,10 +214,10 @@ check_line_number(Last,Line,OrigLine) ->
 	    [$>|Rest] = lists:dropwhile(fun($>) -> false; (_) -> true end,Line),
 	    check_line_number(Last,Rest,OrigLine);
 	_ ->
-	    [N |_] = string:tokens(Line,":"),
+	    [N |_] = string:lexemes(Line,":"),
 %	    erlang:display(N),
 	    Num =
-		try list_to_integer(string:strip(N))
+		try list_to_integer(string:trim(N,both,"\s"))
 		catch _:_ -> ct:fail({no_line_number_after,Last,OrigLine})
 		end,
 	    if Num == Last+1 ->
diff --git a/lib/common_test/test/telnet_server.erl b/lib/common_test/test/telnet_server.erl
index 65300b0bdf..cef7784333 100644
--- a/lib/common_test/test/telnet_server.erl
+++ b/lib/common_test/test/telnet_server.erl
@@ -249,7 +249,7 @@ do_handle_data("echo " ++ Data,State) ->
     send(Data++"\r\n> ",State),
     {ok,State};
 do_handle_data("echo_sep " ++ Data,State) ->
-    Msgs = string:tokens(Data," "),
+    Msgs = string:lexemes(Data," "),
     lists:foreach(fun(Msg) ->
 			  send(Msg,State),
 			  timer:sleep(10)
@@ -260,28 +260,28 @@ do_handle_data("echo_no_prompt " ++ Data,State) ->
     send(Data,State),
     {ok,State};
 do_handle_data("echo_ml " ++ Data,State) ->
-    Lines = string:tokens(Data," "),
-    ReturnData = string:join(Lines,"\n"),
+    Lines = string:lexemes(Data," "),
+    ReturnData = lists:flatten(lists:join("\n",Lines)),
     send(ReturnData++"\r\n> ",State),
     {ok,State};
 do_handle_data("echo_ml_no_prompt " ++ Data,State) ->
-    Lines = string:tokens(Data," "),
-    ReturnData = string:join(Lines,"\n"),
+    Lines = string:lexemes(Data," "),
+    ReturnData = lists:flatten(lists:join("\n",Lines)),
     send(ReturnData,State),
     {ok,State};
 do_handle_data("echo_loop " ++ Data,State) ->
-    [TStr|Lines] = string:tokens(Data," "),
-    ReturnData = string:join(Lines,"\n"),
+    [TStr|Lines] = string:lexemes(Data," "),
+    ReturnData = lists:flatten(lists:join("\n",Lines)),
     send_loop(list_to_integer(TStr),ReturnData,State),
     {ok,State};
 do_handle_data("echo_delayed_prompt "++Data,State) ->
-    [MsStr|EchoData] = string:tokens(Data, " "),
-    send(string:join(EchoData,"\n"),State),
+    [MsStr|EchoData] = string:lexemes(Data, " "),
+    send(lists:flatten(lists:join("\n",EchoData)),State),
     timer:sleep(list_to_integer(MsStr)),
     send("\r\n> ",State),
     {ok,State};
 do_handle_data("disconnect_after " ++WaitStr,State) ->
-    Wait = list_to_integer(string:strip(WaitStr,right,$\n)),
+    Wait = list_to_integer(string:trim(WaitStr,trailing,"\n")),
     dbg("Server will close connection in ~w ms...", [Wait]),
     erlang:send_after(Wait,self(),disconnect),
     {ok,State};
diff --git a/lib/common_test/test/test_server_SUITE.erl b/lib/common_test/test/test_server_SUITE.erl
index 50d8bdd1ac..edfaea1d08 100644
--- a/lib/common_test/test/test_server_SUITE.erl
+++ b/lib/common_test/test/test_server_SUITE.erl
@@ -71,7 +71,7 @@ init_per_testcase(_TestCase, Config) ->
 %% @spec end_per_testcase(TestCase, Config0) ->
 %%               void() | {save_config,Config1} | {fail,Reason}
 end_per_testcase(test_server_unicode, _Config) ->
-    [_,Host] = string:tokens(atom_to_list(node()), "@"),
+    [_,Host] = string:lexemes(atom_to_list(node()), "@"),
     N1 = list_to_atom("test_server_tester_latin1" ++ "@" ++ Host),
     N2 = list_to_atom("test_server_tester_utf8" ++ "@" ++ Host),
     test_server:stop_node(N1),
@@ -347,7 +347,7 @@ generate_and_run_unicode_test(Config0,Encoding) ->
     RunDir = get_latest_run_dir(LogDir),
     true = filelib:is_dir(RunDir),
 
-    LowerModStr = string:to_lower(ModStr),
+    LowerModStr = string:lowercase(ModStr),
     SuiteHtml = translate_filename(LowerModStr++".src.html",Encoding),
     true = filelib:is_regular(filename:join(RunDir,SuiteHtml)),
 
@@ -362,7 +362,7 @@ generate_and_run_unicode_test(Config0,Encoding) ->
 %% remote file system on master - i.e. they will use same file name
 %% mode as the master.
 start_node(Config,Name,Args) ->
-    [_,Host] = string:tokens(atom_to_list(node()), "@"),
+    [_,Host] = string:lexemes(atom_to_list(node()), "@"),
     ct:log("Trying to start ~w@~s~n",[Name,Host]),
     case test_server:start_node(Name, peer, [{args,Args}]) of
 	{error,Reason} ->
diff --git a/lib/common_test/test/test_server_test_lib.erl b/lib/common_test/test/test_server_test_lib.erl
index c18b89b178..9ee946af0b 100644
--- a/lib/common_test/test/test_server_test_lib.erl
+++ b/lib/common_test/test/test_server_test_lib.erl
@@ -43,7 +43,7 @@ pre_init_per_testcase(_TC,Config,State) ->
     {start_slave(Config, 50),State}.
 
 start_slave(Config,_Level) ->
-    [_,Host] = string:tokens(atom_to_list(node()), "@"),
+    [_,Host] = string:lexemes(atom_to_list(node()), "@"),
     
     ct:log("Trying to start ~s~n", 
 	   ["test_server_tester@"++Host]),
@@ -121,7 +121,7 @@ parse_suite(FileName) ->
     end.
 
 fline(Fd) ->
-    case prim_file:read_line(Fd) of
+    case file:read_line(Fd) of
 	eof -> eof;
 	{ok, Line} -> Line
     end.
diff --git a/lib/common_test/test_server/ts.erl b/lib/common_test/test_server/ts.erl
index 5bfea9f4de..330652e73f 100644
--- a/lib/common_test/test_server/ts.erl
+++ b/lib/common_test/test_server/ts.erl
@@ -583,7 +583,7 @@ is_list_of_suites(List) ->
 		      S = if is_atom(Suite) -> atom_to_list(Suite);
 			     true -> Suite
 			  end,
-		      try lists:last(string:tokens(S,"_")) of
+		      try lists:last(string:lexemes(S,"_")) of
 			  "SUITE" -> true;
 			  "suite" -> true;
 			  _ -> false
diff --git a/lib/common_test/test_server/ts_autoconf_win32.erl b/lib/common_test/test_server/ts_autoconf_win32.erl
index 52e5ac8e69..6f6caaeb70 100644
--- a/lib/common_test/test_server/ts_autoconf_win32.erl
+++ b/lib/common_test/test_server/ts_autoconf_win32.erl
@@ -228,7 +228,7 @@ make(Vars) ->
     end.
 
 find_make(MakeCmd, Vars) ->
-    [Make|_] = string:tokens(MakeCmd, " \t"),
+    [Make|_] = string:lexemes(MakeCmd, " \t"),
     case os:find_executable(Make) of
 	false ->
 	    {no, Vars};
@@ -248,9 +248,9 @@ javac(Vars) ->
     end.
 
 is_debug_build() ->
-    case catch string:str(erlang:system_info(system_version), "debug") of
-	Int when is_integer(Int), Int > 0 ->
-	    true;
-	_ ->
-	    false
+    case catch string:find(erlang:system_info(system_version), "debug") of
+        nomatch ->
+            false;
+	_Else ->
+	    true
     end.
diff --git a/lib/common_test/test_server/ts_erl_config.erl b/lib/common_test/test_server/ts_erl_config.erl
index 032593bdda..c7fe4ccf83 100644
--- a/lib/common_test/test_server/ts_erl_config.erl
+++ b/lib/common_test/test_server/ts_erl_config.erl
@@ -311,7 +311,7 @@ lib_dir(Vars, Lib) ->
 			  end,
 	    CLibDir = filename:join(CLibDirList),
 	    Cmd = "ls -d " ++ CLibDir ++ "*",
-	    XLibDir = lists:last(string:tokens(os:cmd(Cmd),"\n")),
+	    XLibDir = lists:last(string:lexemes(os:cmd(Cmd),"\n")),
 	    case file:list_dir(XLibDir) of
 		{error, enoent} ->
 		    [];
@@ -361,15 +361,11 @@ emu_vars(Vars) ->
      {erl_name, atom_to_list(lib:progname())}|Vars].
 
 is_source_build() ->
-    string:str(erlang:system_info(system_version), "[source]") > 0.
+    string:find(erlang:system_info(system_version), "source") =/= nomatch.
 
 is_debug_build() ->
-    case catch string:str(erlang:system_info(system_version), "debug") of
-	Int when is_integer(Int), Int > 0 ->
-	    true;
-	_ ->
-	    false
-    end.
+    string:find(erlang:system_info(system_version), "debug") =/= nomatch.
+
 %%
 %% ssl_libdir
 %%
diff --git a/lib/common_test/test_server/ts_install.erl b/lib/common_test/test_server/ts_install.erl
index c4e0223ac7..048e5493d2 100644
--- a/lib/common_test/test_server/ts_install.erl
+++ b/lib/common_test/test_server/ts_install.erl
@@ -115,7 +115,7 @@ get_vars(_, _, _, _) ->
 config_flags() ->
     case os:getenv("CONFIG_FLAGS") of
 	false -> [];
-	CF -> string:tokens(CF, " \t\n")
+	CF -> string:lexemes(CF, " \t\n")
     end.
 
 unix_autoconf(XConf) ->
@@ -127,7 +127,7 @@ unix_autoconf(XConf) ->
     Threads = [" --enable-shlib-thread-safety" ||
 		  erlang:system_info(threads) /= false],
     Debug = [" --enable-debug-mode" ||
-		string:str(erlang:system_info(system_version),"debug") > 0],
+		string:find(erlang:system_info(system_version),"debug") =/= nomatch],
     MXX_Build = [Y || Y <- config_flags(),
 		      Y == "--enable-m64-build"
 			  orelse Y == "--enable-m32-build"],
@@ -159,10 +159,8 @@ assign_vars([]) ->
 assign_vars([{VAR,FlagsStr} | VARs]) ->
     [{VAR,assign_vars(FlagsStr)} | assign_vars(VARs)];
 assign_vars(FlagsStr) ->
-    Flags = [assign_all_vars(Str,[]) || Str <- string:tokens(FlagsStr, [$ ])],
-    string:strip(lists:flatten(lists:map(fun(Flag) ->
-						 Flag ++ " "
-					 end, Flags)), right).
+    Flags = [assign_all_vars(Str,[]) || Str <- string:lexemes(FlagsStr, [$\s])],
+    lists:flatten(lists:join(" ", Flags)).
 
 assign_all_vars([$$ | Rest], FlagSoFar) ->
     {VarName,Rest1} = get_var_name(Rest, []),
@@ -292,7 +290,7 @@ add_vars(Vars0, Opts0) ->
 get_testcase_callback() ->
     case os:getenv("TS_TESTCASE_CALLBACK") of
 	ModFunc when is_list(ModFunc), ModFunc /= "" ->
-	    case string:tokens(ModFunc, " ") of
+	    case string:lexemes(ModFunc, " ") of
 		[_Mod,_Func] -> ModFunc;
 		_ -> ""
 	    end;
@@ -408,17 +406,13 @@ off_heap_msgq() ->
     end.
 
 schedulers() ->
-    case catch erlang:system_info(smp_support) of
-	true ->
-	    case {erlang:system_info(schedulers),
-		  erlang:system_info(schedulers_online)} of
-		{S,S} ->
-		    "/S"++integer_to_list(S);
-		{S,O} ->
-		    "/S"++integer_to_list(S) ++ ":" ++
-			integer_to_list(O)
-	    end;
-	_ -> ""
+    case {erlang:system_info(schedulers),
+          erlang:system_info(schedulers_online)} of
+        {S,S} ->
+            "/S"++integer_to_list(S);
+        {S,O} ->
+            "/S"++integer_to_list(S) ++ ":" ++
+                integer_to_list(O)
     end.
 
 bind_type() ->
@@ -434,8 +428,8 @@ bind_type() ->
 					
 
 debug() ->
-    case string:str(erlang:system_info(system_version), "debug") of
-	0 -> "";
+    case string:find(erlang:system_info(system_version), "debug") of
+	nomatch -> "";
 	_ -> "/Debug"
     end.
 
diff --git a/lib/common_test/test_server/ts_lib.erl b/lib/common_test/test_server/ts_lib.erl
index ea039a2c2b..da8d676b18 100644
--- a/lib/common_test/test_server/ts_lib.erl
+++ b/lib/common_test/test_server/ts_lib.erl
@@ -99,7 +99,7 @@ specialized_specs(Dir,PostFix) ->
     sort_tests([begin
 		    DirPart = filename:dirname(Name),
 		    AppTest = hd(lists:reverse(filename:split(DirPart))),
-		    list_to_atom(string:substr(AppTest, 1, length(AppTest)-5))
+		    list_to_atom(string:slice(AppTest, 0, string:length(AppTest)-5))
 		end || Name <- Specs]).
 
 specs(Dir) ->
@@ -111,9 +111,9 @@ specs(Dir) ->
 			      [Spec,TestDir|_] =
 				  lists:reverse(filename:split(FullName)),
 			      [_TestSuffix|TDParts] = 
-				  lists:reverse(string:tokens(TestDir,[$_,$.])),
+				  lists:reverse(string:lexemes(TestDir,[$_,$.])),
 			      [_SpecSuffix|SParts] = 
-				  lists:reverse(string:tokens(Spec,[$_,$.])),
+				  lists:reverse(string:lexemes(Spec,[$_,$.])),
 			      if TDParts == SParts ->
 				      [filename_to_atom(FullName)];	  
 				 true ->
@@ -273,7 +273,7 @@ do_test(Rest, Vars, Test) ->
 get_arg([$(|Rest], Vars, Stop, _) ->		
     get_arg(Rest, Vars, Stop, []); 
 get_arg([Stop|Rest], Vars, Stop, Acc) ->
-    Arg = string:strip(lists:reverse(Acc)),
+    Arg = string:trim(lists:reverse(Acc),both,[$\s]),
     Subst = subst(Arg, Vars),
     {Subst,Rest};
 get_arg([C|Rest], Vars, Stop, Acc) ->
diff --git a/lib/common_test/test_server/ts_run.erl b/lib/common_test/test_server/ts_run.erl
index e22fa8d196..3f594236bc 100644
--- a/lib/common_test/test_server/ts_run.erl
+++ b/lib/common_test/test_server/ts_run.erl
@@ -207,11 +207,7 @@ make_command(Vars, Spec, State) ->
 		      _ ->
 			  ok
 		  end,
-		  "cerl -valgrind" ++
-		      case erlang:system_info(smp_support) of
-			  true -> " -smp";
-			  false -> ""
-		      end
+		  "cerl -valgrind"
 	  end,
     Naming =
 	case ts_lib:var(longnames, Vars) of
@@ -468,4 +464,4 @@ split_one(Path) ->
     filename:split(Path).
 
 split_path(Path) ->
-    string:tokens(Path,";").
+    string:lexemes(Path,";").
diff --git a/lib/compiler/doc/src/compile.xml b/lib/compiler/doc/src/compile.xml
index 10164890f2..06afc55c07 100644
--- a/lib/compiler/doc/src/compile.xml
+++ b/lib/compiler/doc/src/compile.xml
@@ -123,6 +123,17 @@
 	    in the Efficiency Guide.</p>
           </item>
 
+          <tag><c>{compile_info, [{atom(), term()}]}</c></tag>
+          <item>
+            <p>Allows compilers built on top of <c>compile</c> to attach
+            extra compilation metadata to the <c>compile_info</c> chunk
+            in the generated beam file.</p>
+
+            <p>It is advised for compilers to remove all non-deterministic
+            information if the <c>deterministic</c> option is supported and
+            it was supplied by the user.</p>
+          </item>
+
           <tag><c>compressed</c></tag>
           <item>
             <p>The compiler will compress the generated object code,
@@ -222,6 +233,15 @@ module.beam: module.erl \
   header.hrl</code>
           </item>
 
+          <tag><c>makedep_side_effect</c></tag>
+          <item>
+	    <p>The dependecies are created as a side effect to the
+	    normal compilation process. This means that the object
+	    file will also be produced. This option override the
+	    <c>makedep</c> option.
+	    </p>
+	  </item>
+
           <tag><c>{makedep_output, Output}</c></tag>
           <item>
             <p>Writes generated rules to <c>Output</c> instead of the
diff --git a/lib/compiler/internal_doc/cerl-notes.md b/lib/compiler/internal_doc/cerl-notes.md
new file mode 100644
index 0000000000..705fe8f42d
--- /dev/null
+++ b/lib/compiler/internal_doc/cerl-notes.md
@@ -0,0 +1,75 @@
+Some notes on the cerl modules
+==============================
+
+Maps in cerl_clauses:match/3
+----------------------------
+
+Not much optimization is done for maps in `cerl_clauses:match/3`.
+
+The reason is that the inliner (`cerl_inline`) was not designed for
+data types that depend on variables bound in the enclosing environment
+(for example, the keys for maps).  If we attempt to extend the
+optimizations for maps similar to the optimizations for the other data
+types, the inliner will crash for certain code.  Here is an example of
+code that would crash the inliner:
+
+     t() ->
+        f(key).
+
+     f(K) ->
+        case #{K => value} of
+          #{key := V} -> V
+        end.
+
+The reason for the crash is that the inliner works in several
+passes and calls `cerl_clauses:match/3` twice.  The inliner will
+assume that the same result will be returned both times, but
+for this example different bindings will be returned.
+
+Here is the rough outline of what happens:
+
+* The first time `cerl_clauses:match/3` will be asked to match the
+pattern `#{K := V}` against `#{key => value}`. It cannot say more
+than that the pattern *may* match.
+
+* Now the inliner will add the bindings to body of the clause (which
+is simply `V`).  In this case, the bindings are still empty, so
+nothing is added.
+
+* The inliner will now do some substitutions and renaming.  The
+variable `K` will be replaced with `key`.
+
+* The next time `cerl_clauses:match/3` is called, it will be asked to
+match the pattern `#{key := V}` against `#{key => value#}`.  In this
+case, there will be a match and the bindings can be extended with
+`{V,value}`.
+
+* The inliner will see that the entire case can be removed.  Only
+the body for the clause needs to be kept.
+
+Thus, after inlining the function `t/0` will look like this:
+
+     t() ->
+        V.
+
+The problem here is that the inliner assumed that the bindings from
+the first and second call to `cer_clauses:match/3` would be the same.
+It used the empty bindings from the first call for the body.
+
+The correct way would be to add the bindings from the second call:
+
+     t() ->
+        let V = value in V.
+
+### How to fix this ###
+
+The inliner will need to call `cerl_clauses:match/3` after doing
+all substitutions and renaming.  It is not clear to me how difficult
+that would be.  I assume that the inliner is written the way it is
+for a good reason.  That means that switching the order things are
+done would lead to correctness and/or performance problems.
+
+### What must also be done to fix this ###
+
+`cerl_inline:make_template/3` must be extended to create a template
+for maps.  That is relatively straightforward.
diff --git a/lib/compiler/src/Makefile b/lib/compiler/src/Makefile
index ef6db66ff6..9e96147787 100644
--- a/lib/compiler/src/Makefile
+++ b/lib/compiler/src/Makefile
@@ -83,6 +83,7 @@ MODULES =  \
 	core_scan \
 	erl_bifs \
 	rec_env \
+	sys_core_alias \
 	sys_core_bsm \
 	sys_core_dsetel \
 	sys_core_fold \
@@ -92,16 +93,14 @@ MODULES =  \
 	v3_codegen \
 	v3_core \
 	v3_kernel \
-	v3_kernel_pp \
-	v3_life
+	v3_kernel_pp
 
 BEAM_H = $(wildcard ../priv/beam_h/*.h)
 
 HRL_FILES= \
 	beam_disasm.hrl \
 	core_parse.hrl \
-	v3_kernel.hrl \
-	v3_life.hrl
+	v3_kernel.hrl
 
 YRL_FILE = core_parse.yrl
 
@@ -186,7 +185,7 @@ release_docs_spec:
 # ---------------------------------------------------- 
 
 $(EBIN)/beam_disasm.beam: $(EGEN)/beam_opcodes.hrl beam_disasm.hrl
-$(EBIN)/beam_listing.beam: v3_life.hrl
+$(EBIN)/beam_listing.beam: core_parse.hrl v3_kernel.hrl
 $(EBIN)/beam_validator.beam: beam_disasm.hrl
 $(EBIN)/cerl.beam: core_parse.hrl
 $(EBIN)/compile.beam: core_parse.hrl ../../stdlib/include/erl_compile.hrl
@@ -194,12 +193,12 @@ $(EBIN)/core_lib.beam: core_parse.hrl
 $(EBIN)/core_lint.beam: core_parse.hrl
 $(EBIN)/core_parse.beam: core_parse.hrl $(EGEN)/core_parse.erl
 $(EBIN)/core_pp.beam: core_parse.hrl
+$(EBIN)/sys_core_alias.beam: core_parse.hrl
 $(EBIN)/sys_core_dsetel.beam: core_parse.hrl
 $(EBIN)/sys_core_fold.beam: core_parse.hrl
 $(EBIN)/sys_core_fold_lists.beam: core_parse.hrl
 $(EBIN)/sys_core_inline.beam: core_parse.hrl
-$(EBIN)/v3_codegen.beam: v3_life.hrl
+$(EBIN)/v3_codegen.beam: v3_kernel.hrl
 $(EBIN)/v3_core.beam: core_parse.hrl
 $(EBIN)/v3_kernel.beam: core_parse.hrl v3_kernel.hrl
 $(EBIN)/v3_kernel_pp.beam: v3_kernel.hrl
-$(EBIN)/v3_life.beam: v3_kernel.hrl v3_life.hrl
diff --git a/lib/compiler/src/beam_a.erl b/lib/compiler/src/beam_a.erl
index cdb32d5d55..6f09dc4be4 100644
--- a/lib/compiler/src/beam_a.erl
+++ b/lib/compiler/src/beam_a.erl
@@ -42,8 +42,7 @@ function({function,Name,Arity,CLabel,Is0}) ->
 	Is = beam_jump:remove_unused_labels(Is1),
 	{function,Name,Arity,CLabel,Is}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [Name,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
diff --git a/lib/compiler/src/beam_asm.erl b/lib/compiler/src/beam_asm.erl
index f7c838e392..453e00fce3 100644
--- a/lib/compiler/src/beam_asm.erl
+++ b/lib/compiler/src/beam_asm.erl
@@ -21,10 +21,10 @@
 
 -module(beam_asm).
 
--export([module/5]).
+-export([module/4]).
 -export([encode/2]).
 
--export_type([fail/0,label/0,reg/0,src/0,module_code/0,function_name/0]).
+-export_type([fail/0,label/0,reg/0,reg_num/0,src/0,module_code/0,function_name/0]).
 
 -import(lists, [map/2,member/2,keymember/3,duplicate/2,splitwith/2]).
 -include("beam_opcodes.hrl").
@@ -55,20 +55,20 @@
 -type module_code() ::
         {module(),[_],[_],[asm_function()],pos_integer()}.
 
--spec module(module_code(), [{binary(), binary()}], [_], [compile:option()], [compile:option()]) ->
+-spec module(module_code(), [{binary(), binary()}], [{atom(),term()}], [compile:option()]) ->
                     {'ok',binary()}.
 
-module(Code, ExtraChunks, SourceFile, Opts, CompilerOpts) ->
-    {ok,assemble(Code, ExtraChunks, SourceFile, Opts, CompilerOpts)}.
+module(Code, ExtraChunks, CompileInfo, CompilerOpts) ->
+    {ok,assemble(Code, ExtraChunks, CompileInfo, CompilerOpts)}.
 
-assemble({Mod,Exp0,Attr0,Asm0,NumLabels}, ExtraChunks, SourceFile, Opts, CompilerOpts) ->
+assemble({Mod,Exp0,Attr0,Asm0,NumLabels}, ExtraChunks, CompileInfo, CompilerOpts) ->
     {1,Dict0} = beam_dict:atom(Mod, beam_dict:new()),
     {0,Dict1} = beam_dict:fname(atom_to_list(Mod) ++ ".erl", Dict0),
     NumFuncs = length(Asm0),
     {Asm,Attr} = on_load(Asm0, Attr0),
     Exp = cerl_sets:from_list(Exp0),
     {Code,Dict2} = assemble_1(Asm, Exp, Dict1, []),
-    build_file(Code, Attr, Dict2, NumLabels, NumFuncs, ExtraChunks, SourceFile, Opts, CompilerOpts).
+    build_file(Code, Attr, Dict2, NumLabels, NumFuncs, ExtraChunks, CompileInfo, CompilerOpts).
 
 on_load(Fs0, Attr0) ->
     case proplists:get_value(on_load, Attr0) of
@@ -111,7 +111,7 @@ assemble_function([H|T], Acc, Dict0) ->
 assemble_function([], Code, Dict) ->
     {Code, Dict}.
 
-build_file(Code, Attr, Dict, NumLabels, NumFuncs, ExtraChunks, SourceFile, Opts, CompilerOpts) ->
+build_file(Code, Attr, Dict, NumLabels, NumFuncs, ExtraChunks, CompileInfo, CompilerOpts) ->
     %% Create the code chunk.
 
     CodeChunk = chunk(<<"Code">>,
@@ -182,8 +182,7 @@ build_file(Code, Attr, Dict, NumLabels, NumFuncs, ExtraChunks, SourceFile, Opts,
     Essentials1 = [iolist_to_binary(C) || C <- Essentials0],
     MD5 = module_md5(Essentials1),
     Essentials = finalize_fun_table(Essentials1, MD5),
-    {Attributes,Compile} = build_attributes(Opts, CompilerOpts, SourceFile,
-                                            Attr, MD5),
+    {Attributes,Compile} = build_attributes(Attr, CompileInfo, MD5),
     AttrChunk = chunk(<<"Attr">>, Attributes),
     CompileChunk = chunk(<<"CInf">>, Compile),
 
@@ -193,7 +192,7 @@ build_file(Code, Attr, Dict, NumLabels, NumFuncs, ExtraChunks, SourceFile, Opts,
 
     %% Create IFF chunk.
 
-    Chunks = case member(slim, Opts) of
+    Chunks = case member(slim, CompilerOpts) of
 		 true ->
 		     [Essentials,AttrChunk];
 		 false ->
@@ -241,9 +240,7 @@ build_form(Id, Chunks0) when byte_size(Id) =:= 4, is_list(Chunks0) ->
 
 chunk(Id, Contents) when byte_size(Id) =:= 4, is_binary(Contents) ->
     Size = byte_size(Contents),
-    [<<Id/binary,Size:32>>,Contents|pad(Size)];
-chunk(Id, Contents) when is_list(Contents) ->
-    chunk(Id, list_to_binary(Contents)).
+    [<<Id/binary,Size:32>>,Contents|pad(Size)].
 
 %% Build a correctly padded chunk (with a sub-header).
 
@@ -265,22 +262,10 @@ flatten_exports(Exps) ->
 flatten_imports(Imps) ->
     list_to_binary(map(fun({M,F,A}) -> <<M:32,F:32,A:32>> end, Imps)).
 
-build_attributes(Opts, CompilerOpts, SourceFile, Attr, MD5) ->
-    Misc0 = case SourceFile of
-		[] -> [];
-		[_|_] -> [{source,SourceFile}]
-	    end,
-    Misc = case member(slim, CompilerOpts) of
-	       false -> Misc0;
-	       true -> []
-	   end,
-    Compile = case member(deterministic, CompilerOpts) of
-		  false ->
-		      [{options,Opts},{version,?COMPILER_VSN}|Misc];
-		  true ->
-		      [{version,?COMPILER_VSN}]
-	      end,
-    {term_to_binary(set_vsn_attribute(Attr, MD5)),term_to_binary(Compile)}.
+build_attributes(Attr, Compile, MD5) ->
+    AttrBinary = term_to_binary(set_vsn_attribute(Attr, MD5)),
+    CompileBinary = term_to_binary([{version,?COMPILER_VSN}|Compile]),
+    {AttrBinary,CompileBinary}.
 
 build_line_table(Dict) ->
     {NumLineInstrs,NumFnames0,Fnames0,NumLines,Lines0} =
diff --git a/lib/compiler/src/beam_block.erl b/lib/compiler/src/beam_block.erl
index 6543e05e20..fe1ce6f60b 100644
--- a/lib/compiler/src/beam_block.erl
+++ b/lib/compiler/src/beam_block.erl
@@ -37,16 +37,16 @@ function({function,Name,Arity,CLabel,Is0}) ->
 	%% Collect basic blocks and optimize them.
 	Is1 = blockify(Is0),
 	Is2 = embed_lines(Is1),
-	Is3 = move_allocates(Is2),
-	Is4 = beam_utils:live_opt(Is3),
-	Is5 = opt_blocks(Is4),
-	Is6 = beam_utils:delete_live_annos(Is5),
-
-	%% Done.
-	{function,Name,Arity,CLabel,Is6}
+        Is3 = beam_utils:anno_defs(Is2),
+        Is4 = move_allocates(Is3),
+        Is5 = beam_utils:live_opt(Is4),
+        Is6 = opt_blocks(Is5),
+        Is = beam_utils:delete_live_annos(Is6),
+
+        %% Done.
+        {function,Name,Arity,CLabel,Is}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [Name,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
@@ -173,7 +173,7 @@ find_fixpoint(OptFun, Is0) ->
 %%  safe to assume that if x(N) is initialized, then all lower-numbered
 %%  x registers are also initialized.
 %%
-%%  For example, in general it is not safe to transform the following
+%%  For example, we must be careful when transforming the following
 %%  instructions:
 %%
 %%     get_tuple_element x(0) Element => x(1)
@@ -185,13 +185,9 @@ find_fixpoint(OptFun, Is0) ->
 %%     get_tuple_element x(0) Element => x(1)
 %%
 %%  The transformation is safe if and only if x(1) has been
-%%  initialized previously. Unfortunately, beam_reorder may have moved
-%%  a get_tuple_element instruction so that x(1) is not always
-%%  initialized when this code is reached. To find whether or not x(1)
-%%  is initialized, we would need to analyze all code preceding these
-%%  two instructions (across branches). Since we currently don't have
-%%  any practical mechanism for doing that, we will have to
-%%  conservatively assume that the transformation is unsafe.
+%%  initialized previously.  We will use the annotations added by
+%%  beam_utils:anno_defs/1 to determine whether x(a) has been
+%%  initialized.
 
 move_allocates([{block,Bl0}|Is]) ->
     Bl = move_allocates_1(reverse(Bl0), []),
@@ -200,15 +196,20 @@ move_allocates([I|Is]) ->
     [I|move_allocates(Is)];
 move_allocates([]) -> [].
 
+move_allocates_1([{'%def',_}|Is], Acc) ->
+    move_allocates_1(Is, Acc);
 move_allocates_1([I|Is], [{set,[],[],{alloc,Live0,Info}}|Acc]=Acc0) ->
-    case {alloc_may_pass(I),alloc_live_regs(I, Live0)} of
-	{false,_} ->
-	    move_allocates_1(Is, [I|Acc0]);
-	{true,not_possible} ->
-	    move_allocates_1(Is, [I|Acc0]);
-	{true,Live} when is_integer(Live) ->
-	    A = {set,[],[],{alloc,Live,Info}},
-	    move_allocates_1(Is, [A,I|Acc])
+    case alloc_may_pass(I) of
+        false ->
+            move_allocates_1(Is, [I|Acc0]);
+        true ->
+            case alloc_live_regs(I, Is, Live0) of
+                not_possible ->
+                    move_allocates_1(Is, [I|Acc0]);
+                Live when is_integer(Live) ->
+                    A = {set,[],[],{alloc,Live,Info}},
+                    move_allocates_1(Is, [A,I|Acc])
+            end
     end;
 move_allocates_1([I|Is], Acc) ->
     move_allocates_1(Is, [I|Acc]);
@@ -219,11 +220,20 @@ alloc_may_pass({set,_,_,{set_tuple_element,_}}) -> false;
 alloc_may_pass({set,_,_,put_list}) -> false;
 alloc_may_pass({set,_,_,put}) -> false;
 alloc_may_pass({set,_,_,_}) -> true.
-    
+
 %% opt([Instruction]) -> [Instruction]
 %%  Optimize the instruction stream inside a basic block.
 
 opt([{set,[X],[X],move}|Is]) -> opt(Is);
+opt([{set,[X],_,move},{set,[X],_,move}=I|Is]) ->
+    opt([I|Is]);
+opt([{set,[{x,0}],[S1],move}=I1,{set,[D2],[{x,0}],move}|Is]) ->
+    opt([I1,{set,[D2],[S1],move}|Is]);
+opt([{set,[{x,0}],[S1],move}=I1,{set,[D2],[S2],move}|Is0]) when S1 =/= D2 ->
+    %% Place move S x0 at the end of move sequences so that
+    %% loader can merge with the following instruction
+    {Ds,Is} = opt_moves([D2], Is0),
+    [{set,Ds,[S2],move}|opt([I1|Is])];
 opt([{set,_,_,{line,_}}=Line1,
      {set,[D1],[{integer,Idx1},Reg],{bif,element,{f,0}}}=I1,
      {set,_,_,{line,_}}=Line2,
@@ -463,16 +473,34 @@ count_ones(Bits, Acc) ->
 %% Calculate the new number of live registers when we move an allocate
 %% instruction upwards, passing a 'set' instruction.
 
-alloc_live_regs({set,Ds,Ss,_}, Regs0) ->
+alloc_live_regs({set,Ds,Ss,_}, Is, Regs0) ->
     Rset = x_live(Ss, x_dead(Ds, (1 bsl Regs0)-1)),
-    live_regs(0, Rset).
+    Live = live_regs(0, Rset),
+    case ensure_contiguous(Rset, Live) of
+        not_possible ->
+            %% Liveness information (looking forward in the
+            %% instruction stream) can't prove that moving this
+            %% allocation instruction is safe. Now use the annotation
+            %% of defined registers at the beginning of the current
+            %% block to see whether moving would be safe.
+            Def0 = defined_regs(Is, 0),
+            Def = Def0 band ((1 bsl Live) - 1),
+            ensure_contiguous(Rset bor Def, Live);
+        Live ->
+            %% Safe based on liveness information.
+            Live
+    end.
 
 live_regs(N, 0) ->
     N;
-live_regs(N, Regs) when Regs band 1 =:= 1 ->
-    live_regs(N+1, Regs bsr 1);
-live_regs(_, _) ->
-    not_possible.
+live_regs(N, Regs) ->
+    live_regs(N+1, Regs bsr 1).
+
+ensure_contiguous(Regs, Live) ->
+    case (1 bsl Live) - 1 of
+        Regs -> Live;
+        _ -> not_possible
+    end.
 
 x_dead([{x,N}|Rs], Regs) -> x_dead(Rs, Regs band (bnot (1 bsl N)));
 x_dead([_|Rs], Regs) -> x_dead(Rs, Regs);
@@ -481,3 +509,14 @@ x_dead([], Regs) -> Regs.
 x_live([{x,N}|Rs], Regs) -> x_live(Rs, Regs bor (1 bsl N));
 x_live([_|Rs], Regs) -> x_live(Rs, Regs);
 x_live([], Regs) -> Regs.
+
+%% defined_regs(ReversedInstructions) -> RegBitmap.
+%%  Given a reversed instruction stream, determine the
+%%  the registers that are defined.
+
+defined_regs([{'%def',Def}|_], Regs) ->
+    Def bor Regs;
+defined_regs([{set,Ds,_,{alloc,Live,_}}|_], Regs) ->
+    x_live(Ds, Regs bor ((1 bsl Live) - 1));
+defined_regs([{set,Ds,_,_}|Is], Regs) ->
+    defined_regs(Is, x_live(Ds, Regs)).
diff --git a/lib/compiler/src/beam_bs.erl b/lib/compiler/src/beam_bs.erl
index beb055b23d..14cedbb582 100644
--- a/lib/compiler/src/beam_bs.erl
+++ b/lib/compiler/src/beam_bs.erl
@@ -38,8 +38,7 @@ function({function,Name,Arity,CLabel,Is0}, Lc0) ->
 	{Is,Lc} = bsm_opt(Is1, Lc0),
 	{{function,Name,Arity,CLabel,Is},Lc}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [Name,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
diff --git a/lib/compiler/src/beam_bsm.erl b/lib/compiler/src/beam_bsm.erl
index 9a4e7fb133..9ea5a3eb92 100644
--- a/lib/compiler/src/beam_bsm.erl
+++ b/lib/compiler/src/beam_bsm.erl
@@ -105,8 +105,7 @@ function({function,Name,Arity,Entry,Is}, FIndex) ->
 	D = #btb{f=FIndex,index=Index},
 	{function,Name,Arity,Entry,btb_opt_1(Is, D, [])}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [Name,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
diff --git a/lib/compiler/src/beam_clean.erl b/lib/compiler/src/beam_clean.erl
index b736d39f9c..e094c2c320 100644
--- a/lib/compiler/src/beam_clean.erl
+++ b/lib/compiler/src/beam_clean.erl
@@ -24,7 +24,7 @@
 -export([module/2]).
 -export([bs_clean_saves/1]).
 -export([clean_labels/1]).
--import(lists, [map/2,foldl/3,reverse/1,filter/2]).
+-import(lists, [foldl/3,reverse/1,filter/2]).
 
 -spec module(beam_utils:module_code(), [compile:option()]) ->
                     {'ok',beam_utils:module_code()}.
@@ -118,7 +118,7 @@ add_to_work_list(F, {Fs,Used}=Sets) ->
 clean_labels(Fs0) ->
     St0 = #st{lmap=[],entry=1,lc=1},
     {Fs1,#st{lmap=Lmap0,lc=Lc}} = function_renumber(Fs0, St0, []),
-    Lmap = gb_trees:from_orddict(ordsets:from_list(Lmap0)),
+    Lmap = maps:from_list(Lmap0),
     Fs = function_replace(Fs1, Lmap, []),
     {Fs,Lc}.
 
@@ -187,7 +187,8 @@ is_record_tuple(_, _, _) -> no.
 
 function_replace([{function,Name,Arity,Entry,Asm0}|Fs], Dict, Acc) ->
     Asm = try
-	      replace(Asm0, [], Dict)
+              Fb = fun(Old) -> throw({error,{undefined_label,Old}}) end,
+              beam_utils:replace_labels(Asm0, [], Dict, Fb)
 	  catch
 	      throw:{error,{undefined_label,Lbl}=Reason} ->
 		  io:format("Function ~s/~w refers to undefined label ~w\n",
@@ -197,57 +198,6 @@ function_replace([{function,Name,Arity,Entry,Asm0}|Fs], Dict, Acc) ->
     function_replace(Fs, Dict, [{function,Name,Arity,Entry,Asm}|Acc]);
 function_replace([], _, Acc) -> Acc.
 
-replace([{test,Test,{f,Lbl},Ops}|Is], Acc, D) ->
-    replace(Is, [{test,Test,{f,label(Lbl, D)},Ops}|Acc], D);
-replace([{test,Test,{f,Lbl},Live,Ops,Dst}|Is], Acc, D) ->
-    replace(Is, [{test,Test,{f,label(Lbl, D)},Live,Ops,Dst}|Acc], D);
-replace([{select,I,R,{f,Fail0},Vls0}|Is], Acc, D) ->
-    Vls = map(fun ({f,L}) -> {f,label(L, D)};
-		   (Other) -> Other
-	      end, Vls0),
-    Fail = label(Fail0, D),
-    replace(Is, [{select,I,R,{f,Fail},Vls}|Acc], D);
-replace([{'try',R,{f,Lbl}}|Is], Acc, D) ->
-    replace(Is, [{'try',R,{f,label(Lbl, D)}}|Acc], D);
-replace([{'catch',R,{f,Lbl}}|Is], Acc, D) ->
-    replace(Is, [{'catch',R,{f,label(Lbl, D)}}|Acc], D);
-replace([{jump,{f,Lbl}}|Is], Acc, D) ->
-    replace(Is, [{jump,{f,label(Lbl, D)}}|Acc], D);
-replace([{loop_rec,{f,Lbl},R}|Is], Acc, D) ->
-    replace(Is, [{loop_rec,{f,label(Lbl, D)},R}|Acc], D);
-replace([{loop_rec_end,{f,Lbl}}|Is], Acc, D) ->
-    replace(Is, [{loop_rec_end,{f,label(Lbl, D)}}|Acc], D);
-replace([{wait,{f,Lbl}}|Is], Acc, D) ->
-    replace(Is, [{wait,{f,label(Lbl, D)}}|Acc], D);
-replace([{wait_timeout,{f,Lbl},To}|Is], Acc, D) ->
-    replace(Is, [{wait_timeout,{f,label(Lbl, D)},To}|Acc], D);
-replace([{bif,Name,{f,Lbl},As,R}|Is], Acc, D) when Lbl =/= 0 ->
-    replace(Is, [{bif,Name,{f,label(Lbl, D)},As,R}|Acc], D);
-replace([{gc_bif,Name,{f,Lbl},Live,As,R}|Is], Acc, D) when Lbl =/= 0 ->
-    replace(Is, [{gc_bif,Name,{f,label(Lbl, D)},Live,As,R}|Acc], D);
-replace([{call,Ar,{f,Lbl}}|Is], Acc, D) ->
-    replace(Is, [{call,Ar,{f,label(Lbl,D)}}|Acc], D);
-replace([{make_fun2,{f,Lbl},U1,U2,U3}|Is], Acc, D) ->
-    replace(Is, [{make_fun2,{f,label(Lbl, D)},U1,U2,U3}|Acc], D);
-replace([{bs_init,{f,Lbl},Info,Live,Ss,Dst}|Is], Acc, D) when Lbl =/= 0 ->
-    replace(Is, [{bs_init,{f,label(Lbl, D)},Info,Live,Ss,Dst}|Acc], D);
-replace([{bs_put,{f,Lbl},Info,Ss}|Is], Acc, D) when Lbl =/= 0 ->
-    replace(Is, [{bs_put,{f,label(Lbl, D)},Info,Ss}|Acc], D);
-replace([{put_map=I,{f,Lbl},Op,Src,Dst,Live,List}|Is], Acc, D)
-  when Lbl =/= 0 ->
-    replace(Is, [{I,{f,label(Lbl, D)},Op,Src,Dst,Live,List}|Acc], D);
-replace([{get_map_elements=I,{f,Lbl},Src,List}|Is], Acc, D) when Lbl =/= 0 ->
-    replace(Is, [{I,{f,label(Lbl, D)},Src,List}|Acc], D);
-replace([I|Is], Acc, D) ->
-    replace(Is, [I|Acc], D);
-replace([], Acc, _) -> Acc.
-
-label(Old, D) ->
-    case gb_trees:lookup(Old, D) of
-	{value,Val} -> Val;
-	none -> throw({error,{undefined_label,Old}})
-    end.
-
 %%%
 %%% Final fixup of bs_start_match2/5,bs_save2/bs_restore2 instructions for
 %%% new bit syntax matching (introduced in R11B).
diff --git a/lib/compiler/src/beam_dead.erl b/lib/compiler/src/beam_dead.erl
index d379fdc4eb..da944f3ce6 100644
--- a/lib/compiler/src/beam_dead.erl
+++ b/lib/compiler/src/beam_dead.erl
@@ -56,8 +56,7 @@ function({function,Name,Arity,CLabel,Is0}, Lc0) ->
 	Is = move_move_into_block(Is3, []),
 	{{function,Name,Arity,CLabel,Is},Lc}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [Name,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
@@ -272,7 +271,8 @@ backward([{jump,{f,To0}},{move,Src,Reg}=Move|Is], D, Acc) ->
     end;
 backward([{jump,{f,To}}=J|[{bif,Op,{f,BifFail},Ops,Reg}|Is]=Is0], D, Acc) ->
     try replace_comp_op(To, Reg, Op, Ops, D) of
-	I -> backward(Is, D, I++Acc)
+	{Test,Jump} ->
+            backward([Jump,Test|Is], D, Acc)
     catch
 	throw:not_possible ->
 	    case To =:= BifFail of
@@ -446,7 +446,7 @@ prune_redundant([], _) -> [].
 replace_comp_op(To, Reg, Op, Ops, D) ->
     False = comp_op_find_shortcut(To, Reg, {atom,false}, D),
     True = comp_op_find_shortcut(To, Reg, {atom,true}, D),
-    [bif_to_test(Op, Ops, False),{jump,{f,True}}].
+    {bif_to_test(Op, Ops, False),{jump,{f,True}}}.
 
 comp_op_find_shortcut(To0, Reg, Val, D) ->
     case shortcut_select_label(To0, Reg, Val, D) of
@@ -483,15 +483,22 @@ not_possible() -> throw(not_possible).
 %%   F1:  is_eq_exact F2 Reg Lit2          F1: is_eq_exact F2 Reg Lit2
 %%   L2:  ....				   L2:
 %%
-combine_eqs(To, [Reg,{Type,_}=Lit1]=Ops, D, [{label,L1}|_])
-  when Type =:= atom; Type =:= integer ->
+combine_eqs(To, [Reg,{Type,_}=Lit1]=Ops, D, Acc)
+    when Type =:= atom; Type =:= integer ->
+    Next = case Acc of
+               [{label,Lbl}|_] -> Lbl;
+               [{jump,{f,Lbl}}|_] -> Lbl
+           end,
     case beam_utils:code_at(To, D) of
 	[{test,is_eq_exact,{f,F2},[Reg,{Type,_}=Lit2]},
 	 {label,L2}|_] when Lit1 =/= Lit2 ->
-	    {select,select_val,Reg,{f,F2},[Lit1,{f,L1},Lit2,{f,L2}]};
+	    {select,select_val,Reg,{f,F2},[Lit1,{f,Next},Lit2,{f,L2}]};
+	[{test,is_eq_exact,{f,F2},[Reg,{Type,_}=Lit2]},
+	 {jump,{f,L2}}|_] when Lit1 =/= Lit2 ->
+	    {select,select_val,Reg,{f,F2},[Lit1,{f,Next},Lit2,{f,L2}]};
 	[{select,select_val,Reg,{f,F2},[{Type,_}|_]=List0}|_] ->
 	    List = remove_from_list(Lit1, List0),
-	    {select,select_val,Reg,{f,F2},[Lit1,{f,L1}|List]};
+	    {select,select_val,Reg,{f,F2},[Lit1,{f,Next}|List]};
 	_Is ->
 	    {test,is_eq_exact,{f,To},Ops}
 	end;
diff --git a/lib/compiler/src/beam_disasm.erl b/lib/compiler/src/beam_disasm.erl
index 8fd0b36d05..22ba86fa38 100644
--- a/lib/compiler/src/beam_disasm.erl
+++ b/lib/compiler/src/beam_disasm.erl
@@ -163,8 +163,8 @@ pp_instr(I) ->
 
 file(File) ->
     try process_chunks(File)
-    catch error:Reason ->
-	    {error,?MODULE,{internal,{Reason,erlang:get_stacktrace()}}}
+    catch error:Reason:Stack ->
+            {error,?MODULE,{internal,{Reason,Stack}}}
     end.
 
 %%-----------------------------------------------------------------------
@@ -719,42 +719,6 @@ resolve_inst({wait,[Lbl]},_,_,_) ->
     {wait,Lbl};
 resolve_inst({wait_timeout,[Lbl,Int]},_,_,_) ->
     {wait_timeout,Lbl,resolve_arg(Int)};
-resolve_inst({m_plus,Args},_,_,_) ->
-    [W,SrcR1,SrcR2,DstR] = resolve_args(Args),
-    {arithbif,'+',W,[SrcR1,SrcR2],DstR};
-resolve_inst({m_minus,Args},_,_,_) ->
-    [W,SrcR1,SrcR2,DstR] = resolve_args(Args),
-    {arithbif,'-',W,[SrcR1,SrcR2],DstR};
-resolve_inst({m_times,Args},_,_,_) ->
-    [W,SrcR1,SrcR2,DstR] = resolve_args(Args),
-    {arithbif,'*',W,[SrcR1,SrcR2],DstR};
-resolve_inst({m_div,Args},_,_,_) ->
-    [W,SrcR1,SrcR2,DstR] = resolve_args(Args),
-    {arithbif,'/',W,[SrcR1,SrcR2],DstR};
-resolve_inst({int_div,Args},_,_,_) ->
-    [W,SrcR1,SrcR2,DstR] = resolve_args(Args),
-    {arithbif,'div',W,[SrcR1,SrcR2],DstR};
-resolve_inst({int_rem,Args},_,_,_) ->
-    [W,SrcR1,SrcR2,DstR] = resolve_args(Args),
-    {arithbif,'rem',W,[SrcR1,SrcR2],DstR};
-resolve_inst({int_band,Args},_,_,_) ->
-    [W,SrcR1,SrcR2,DstR] = resolve_args(Args),
-    {arithbif,'band',W,[SrcR1,SrcR2],DstR};
-resolve_inst({int_bor,Args},_,_,_) ->
-    [W,SrcR1,SrcR2,DstR] = resolve_args(Args),
-    {arithbif,'bor',W,[SrcR1,SrcR2],DstR};
-resolve_inst({int_bxor,Args},_,_,_) ->
-    [W,SrcR1,SrcR2,DstR] = resolve_args(Args),
-    {arithbif,'bxor',W,[SrcR1,SrcR2],DstR};
-resolve_inst({int_bsl,Args},_,_,_) ->
-    [W,SrcR1,SrcR2,DstR] = resolve_args(Args),
-    {arithbif,'bsl',W,[SrcR1,SrcR2],DstR};
-resolve_inst({int_bsr,Args},_,_,_) ->
-    [W,SrcR1,SrcR2,DstR] = resolve_args(Args),
-    {arithbif,'bsr',W,[SrcR1,SrcR2],DstR};
-resolve_inst({int_bnot,Args},_,_,_) ->
-    [W,SrcR,DstR] = resolve_args(Args),
-    {arithbif,'bnot',W,[SrcR],DstR};
 resolve_inst({is_lt=I,Args0},_,_,_) ->
     [L|Args] = resolve_args(Args0),
     {test,I,L,Args};
@@ -800,9 +764,6 @@ resolve_inst({is_nil=I,Args0},_,_,_) ->
 resolve_inst({is_binary=I,Args0},_,_,_) ->
     [L|Args] = resolve_args(Args0),
     {test,I,L,Args};
-resolve_inst({is_constant=I,Args0},_,_,_) ->
-    [L|Args] = resolve_args(Args0),
-    {test,I,L,Args};
 resolve_inst({is_list=I,Args0},_,_,_) ->
     [L|Args] = resolve_args(Args0),
     {test,I,L,Args};
@@ -840,11 +801,6 @@ resolve_inst({get_tuple_element,[Src,{u,Off},Dst]},_,_,_) ->
     {get_tuple_element,resolve_arg(Src),Off,resolve_arg(Dst)};
 resolve_inst({set_tuple_element,[Src,Dst,{u,Off}]},_,_,_) ->
     {set_tuple_element,resolve_arg(Src),resolve_arg(Dst),Off};
-resolve_inst({put_string,[{u,Len},{u,Off},Dst]},_,Strings,_) ->
-    String = if Len > 0 -> binary_to_list(Strings, Off+1, Off+Len);
-		true -> ""
-	     end,
-    {put_string,Len,{string,String},Dst};
 resolve_inst({put_list,[Src1,Src2,Dst]},_,_,_) ->
     {put_list,resolve_arg(Src1),resolve_arg(Src2),Dst};
 resolve_inst({put_tuple,[{u,Arity},Dst]},_,_,_) ->
@@ -859,9 +815,6 @@ resolve_inst({case_end,[X]},_,_,_) ->
     {case_end,resolve_arg(X)};
 resolve_inst({call_fun,[{u,N}]},_,_,_) ->
     {call_fun,N};
-resolve_inst({make_fun,Args},_,_,Lbls) ->
-    [{f,L},Magic,FreeVars] = resolve_args(Args),
-    {make_fun,lookup(L,Lbls),Magic,FreeVars};
 resolve_inst({is_function=I,Args0},_,_,_) ->
     [L|Args] = resolve_args(Args0),
     {test,I,L,Args};
@@ -870,30 +823,6 @@ resolve_inst({call_ext_only,[{u,N},{u,MFAix}]},Imports,_,_) ->
 %%
 %% Instructions for handling binaries added in R7A & R7B
 %%
-resolve_inst({bs_start_match,[F,Reg]},_,_,_) ->
-    {bs_start_match,F,Reg};
-resolve_inst({bs_get_integer=I,[Lbl,Arg2,{u,N},{u,U},Arg5]},_,_,_) ->
-    [A2,A5] = resolve_args([Arg2,Arg5]),
-    {test,I,Lbl,[A2,N,decode_field_flags(U),A5]};
-resolve_inst({bs_get_float=I,[Lbl,Arg2,{u,N},{u,U},Arg5]},_,_,_) ->
-    [A2,A5] = resolve_args([Arg2,Arg5]),
-    {test,I,Lbl,[A2,N,decode_field_flags(U),A5]};
-resolve_inst({bs_get_binary=I,[Lbl,Arg2,{u,N},{u,U},Arg5]},_,_,_) ->
-    [A2,A5] = resolve_args([Arg2,Arg5]),
-    {test,I,Lbl,[A2,N,decode_field_flags(U),A5]};
-resolve_inst({bs_skip_bits,[Lbl,Arg2,{u,N},{u,U}]},_,_,_) ->
-    A2 = resolve_arg(Arg2),
-    {test,bs_skip_bits,Lbl,[A2,N,decode_field_flags(U)]};
-resolve_inst({bs_test_tail,[F,{u,N}]},_,_,_) ->
-    {test,bs_test_tail,F,[N]};
-resolve_inst({bs_save,[{u,N}]},_,_,_) ->
-    {bs_save,N};
-resolve_inst({bs_restore,[{u,N}]},_,_,_) ->
-    {bs_restore,N};
-resolve_inst({bs_init,[{u,N},{u,U}]},_,_,_) ->
-    {bs_init,N,decode_field_flags(U)};
-resolve_inst({bs_final,[F,X]},_,_,_) ->
-    {bs_final,F,X};
 resolve_inst({bs_put_integer,[Lbl,Arg2,{u,N},{u,U},Arg5]},_,_,_) ->
     [A2,A5] = resolve_args([Arg2,Arg5]),
     {bs_put_integer,Lbl,A2,N,decode_field_flags(U),A5};
@@ -908,8 +837,6 @@ resolve_inst({bs_put_string,[{u,Len},{u,Off}]},_,Strings,_) ->
 		true -> ""
 	     end,
     {bs_put_string,Len,{string,String}};
-resolve_inst({bs_need_buf,[{u,N}]},_,_,_) ->
-    {bs_need_buf,N};
 
 %%
 %% Instructions for handling floating point numbers added in June 2001 (R8).
@@ -961,9 +888,6 @@ resolve_inst({raise,[_Reg1,_Reg2]=Regs},_,_,_) ->
 resolve_inst({bs_init2,[Lbl,Arg2,{u,W},{u,R},{u,F},Arg6]},_,_,_) ->
     [A2,A6] = resolve_args([Arg2,Arg6]),
     {bs_init2,Lbl,A2,W,R,decode_field_flags(F),A6};
-resolve_inst({bs_bits_to_bytes,[Lbl,Arg2,Arg3]},_,_,_) ->
-    [A2,A3] = resolve_args([Arg2,Arg3]),
-    {bs_bits_to_bytes,Lbl,A2,A3};
 resolve_inst({bs_add=I,[Lbl,Arg2,Arg3,Arg4,Arg5]},_,_,_) ->
     [A2,A3,A4,A5] = resolve_args([Arg2,Arg3,Arg4,Arg5]),
     {I,Lbl,[A2,A3,A4],A5};
@@ -1041,12 +965,6 @@ resolve_inst({gc_bif3,Args},Imports,_,_) ->
     {gc_bif,BifName,F,Live,[A1,A2,A3],Reg};
 
 %%
-%% New instructions for creating non-byte aligned binaries.
-%%
-resolve_inst({bs_final2,[X,Y]},_,_,_) ->
-    {bs_final2,X,Y};
-
-%%
 %% R11B-5.
 %% 
 resolve_inst({is_bitstr=I,Args0},_,_,_) ->
@@ -1165,6 +1083,13 @@ resolve_inst({get_map_elements,Args0},_,_,_) ->
     {get_map_elements,FLbl,Src,{list,List}};
 
 %%
+%% OTP 21.
+%%
+
+resolve_inst({build_stacktrace,[]},_,_,_) ->
+    build_stacktrace;
+
+%%
 %% Catches instructions that are not yet handled.
 %%
 resolve_inst(X,_,_,_) -> ?exit({resolve_inst,X}).
diff --git a/lib/compiler/src/beam_disasm.hrl b/lib/compiler/src/beam_disasm.hrl
index d968cd9587..8cc0bcf99b 100644
--- a/lib/compiler/src/beam_disasm.hrl
+++ b/lib/compiler/src/beam_disasm.hrl
@@ -26,7 +26,8 @@
 %%      IT SHOULD BE MOVED TO A FILE THAT DEFINES (AND EXPORTS)
 %%      PROPER TYPES FOR THE SET OF BEAM INSTRUCTIONS.
 %%
--type beam_instr() :: 'bs_init_writable' | 'fclearerror' | 'if_end'
+-type beam_instr() :: 'bs_init_writable' | 'build_stacktrace'
+                    | 'fclearerror' | 'if_end'
                     | 'remove_message' | 'return' | 'send' | 'timeout'
                     | tuple().  %% XXX: Very underspecified - FIX THIS
 
diff --git a/lib/compiler/src/beam_except.erl b/lib/compiler/src/beam_except.erl
index 9801c68ee2..abd39c661d 100644
--- a/lib/compiler/src/beam_except.erl
+++ b/lib/compiler/src/beam_except.erl
@@ -45,8 +45,7 @@ function({function,Name,Arity,CLabel,Is0}) ->
 	Is = function_1(Is0),
 	{function,Name,Arity,CLabel,Is}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [Name,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
diff --git a/lib/compiler/src/beam_jump.erl b/lib/compiler/src/beam_jump.erl
index 4365451356..c33de217bd 100644
--- a/lib/compiler/src/beam_jump.erl
+++ b/lib/compiler/src/beam_jump.erl
@@ -71,9 +71,9 @@
 %%%
 %%%    jump L2
 %%%          . . .
-%%%    L1:
 %%%    L2: ...
 %%%
+%%%    and all preceding uses of L1 renamed to L2.
 %%%    If the jump is unreachable, it will be removed according to (1).
 %%%
 %%% (5) In
@@ -156,41 +156,46 @@ function({function,Name,Arity,CLabel,Asm0}) ->
 %%%
 
 share(Is0) ->
-    %% We will get more sharing if we never fall through to a label.
-    Is = eliminate_fallthroughs(Is0, []),
-    share_1(Is, #{}, [], []).
+    Is1 = eliminate_fallthroughs(Is0, []),
+    Is2 = find_fixpoint(fun(Is) ->
+                                share_1(Is, #{}, #{}, [], [])
+                        end, Is1),
+    reverse(Is2).
 
-share_1([{label,L}=Lbl|Is], Dict0, [_|_]=Seq, Acc) ->
+share_1([{label,L}=Lbl|Is], Dict0, Lbls0, [_|_]=Seq, Acc) ->
     case maps:find(Seq, Dict0) of
 	error ->
 	    Dict = maps:put(Seq, L, Dict0),
-	    share_1(Is, Dict, [], [Lbl|Seq ++ Acc]);
+	    share_1(Is, Dict, Lbls0, [], [Lbl|Seq ++ Acc]);
 	{ok,Label} ->
-	    share_1(Is, Dict0, [], [Lbl,{jump,{f,Label}}|Acc])
+            Lbls = maps:put(L, Label, Lbls0),
+	    share_1(Is, Dict0, Lbls, [], [Lbl,{jump,{f,Label}}|Acc])
     end;
-share_1([{func_info,_,_,_}=I|Is], _, [], Acc) ->
-    reverse(Is, [I|Acc]);
-share_1([{'catch',_,_}=I|Is], Dict0, Seq, Acc) ->
-    Dict = clean_non_sharable(Dict0),
-    share_1(Is, Dict, [I|Seq], Acc);
-share_1([{'try',_,_}=I|Is], Dict0, Seq, Acc) ->
-    Dict = clean_non_sharable(Dict0),
-    share_1(Is, Dict, [I|Seq], Acc);
-share_1([{try_case,_}=I|Is], Dict0, Seq, Acc) ->
-    Dict = clean_non_sharable(Dict0),
-    share_1(Is, Dict, [I|Seq], Acc);
-share_1([{catch_end,_}=I|Is], Dict0, Seq, Acc) ->
-    Dict = clean_non_sharable(Dict0),
-    share_1(Is, Dict, [I|Seq], Acc);
-share_1([I|Is], Dict, Seq, Acc) ->
+share_1([{func_info,_,_,_}|_]=Is, _, Lbls, [], Acc) when Lbls =/= #{} ->
+    beam_utils:replace_labels(Acc, Is, Lbls, fun(Old) -> Old end);
+share_1([{func_info,_,_,_}|_]=Is, _, Lbls, [], Acc) when Lbls =:= #{} ->
+    reverse(Acc, Is);
+share_1([{'catch',_,_}=I|Is], Dict0, Lbls0, Seq, Acc) ->
+    {Dict,Lbls} = clean_non_sharable(Dict0, Lbls0),
+    share_1(Is, Dict, Lbls, [I|Seq], Acc);
+share_1([{'try',_,_}=I|Is], Dict0, Lbls0, Seq, Acc) ->
+    {Dict,Lbls} = clean_non_sharable(Dict0, Lbls0),
+    share_1(Is, Dict, Lbls, [I|Seq], Acc);
+share_1([{try_case,_}=I|Is], Dict0, Lbls0, Seq, Acc) ->
+    {Dict,Lbls} = clean_non_sharable(Dict0, Lbls0),
+    share_1(Is, Dict, Lbls, [I|Seq], Acc);
+share_1([{catch_end,_}=I|Is], Dict0, Lbls0, Seq, Acc) ->
+    {Dict,Lbls} = clean_non_sharable(Dict0, Lbls0),
+    share_1(Is, Dict, Lbls, [I|Seq], Acc);
+share_1([I|Is], Dict, Lbls, Seq, Acc) ->
     case is_unreachable_after(I) of
 	false ->
-	    share_1(Is, Dict, [I|Seq], Acc);
+	    share_1(Is, Dict, Lbls, [I|Seq], Acc);
 	true ->
-	    share_1(Is, Dict, [I], Acc)
+	    share_1(Is, Dict, Lbls, [I], Acc)
     end.
 
-clean_non_sharable(Dict) ->
+clean_non_sharable(Dict0, Lbls0) ->
     %% We are passing in or out of a 'catch' or 'try' block. Remove
     %% sequences that should not be shared over the boundaries of the
     %% block. Since the end of the sequence must match, the only
@@ -198,7 +203,17 @@ clean_non_sharable(Dict) ->
     %% the 'catch'/'try' block is a sequence that ends with an
     %% instruction that causes an exception. Any sequence that causes
     %% an exception must contain a line/1 instruction.
-    maps:filter(fun(K, _V) -> sharable_with_try(K) end, Dict).
+    Dict1 = maps:to_list(Dict0),
+    Lbls1 = maps:to_list(Lbls0),
+    {Dict2,Lbls2} = foldl(fun({K, V}, {Dict,Lbls}) ->
+                                  case sharable_with_try(K) of
+                                      true ->
+                                          {[{K,V}|Dict],lists:keydelete(V, 2, Lbls)};
+                                      false ->
+                                          {Dict,Lbls}
+                                  end
+                          end, {[],Lbls1}, Dict1),
+    {maps:from_list(Dict2),maps:from_list(Lbls2)}.
 
 sharable_with_try([{line,_}|_]) ->
     %% This sequence may cause an exception and may potentially
@@ -275,14 +290,15 @@ extract_seq_1(_, _) -> no.
 -record(st,
 	{
 	  entry :: beam_asm:label(), %Entry label (must not be moved).
-	  mlbl :: #{beam_asm:label() := [beam_asm:label()]}, %Moved labels.
-	  labels :: cerl_sets:set()         %Set of referenced labels.
+	  replace :: #{beam_asm:label() := beam_asm:label()}, %Labels to replace.
+	  labels :: cerl_sets:set(),         %Set of referenced labels.
+          index :: beam_utils:code_index() | {lazy,[beam_utils:instruction()]} %Index built lazily only if needed
 	}).
 
 opt(Is0, CLabel) ->
     find_fixpoint(fun(Is) ->
 			  Lbls = initial_labels(Is),
-			  St = #st{entry=CLabel,mlbl=#{},labels=Lbls},
+			  St = #st{entry=CLabel,replace=#{},labels=Lbls,index={lazy,Is}},
 			  opt(Is, [], St)
 		  end, Is0).
 
@@ -292,7 +308,7 @@ find_fixpoint(OptFun, Is0) ->
 	Is -> find_fixpoint(OptFun, Is)
     end.
 
-opt([{test,_,{f,L}=Lbl,_}=I|[{jump,{f,L}}|_]=Is], Acc, St) ->
+opt([{test,_,{f,L}=Lbl,_}=I|[{jump,{f,L}}|_]=Is], Acc0, St0) ->
     %% We have
     %%    Test Label Ops
     %%    jump Label
@@ -301,10 +317,23 @@ opt([{test,_,{f,L}=Lbl,_}=I|[{jump,{f,L}}|_]=Is], Acc, St) ->
     case beam_utils:is_pure_test(I) of
 	false ->
 	    %% Test is not pure; we must keep it.
-	    opt(Is, [I|Acc], label_used(Lbl, St));
+	    opt(Is, [I|Acc0], label_used(Lbl, St0));
 	true ->
 	    %% The test is pure and its failure label is the same
 	    %% as in the jump that follows -- thus it is not needed.
+            %% Check if any of the previous instructions could also be eliminated.
+            {Acc,St} = opt_useless_loads(Acc0, L, St0),
+	    opt(Is, Acc, St)
+    end;
+opt([{test,_,{f,L}=Lbl,_}=I|[{label,L}|_]=Is], Acc0, St0) ->
+    %% Similar to the above, except we have a fall-through rather than jump
+    %%    Test Label Ops
+    %%    label Label
+    case beam_utils:is_pure_test(I) of
+	false ->
+	    opt(Is, [I|Acc0], label_used(Lbl, St0));
+	true ->
+            {Acc,St} = opt_useless_loads(Acc0, L, St0),
 	    opt(Is, Acc, St)
     end;
 opt([{test,Test0,{f,L}=Lbl,Ops}=I|[{jump,To}|Is]=Is0], Acc, St) ->
@@ -326,30 +355,16 @@ opt([{test,_,{f,_}=Lbl,_,_,_}=I|Is], Acc, St) ->
     opt(Is, [I|Acc], label_used(Lbl, St));
 opt([{select,_,_R,Fail,Vls}=I|Is], Acc, St) ->
     skip_unreachable(Is, [I|Acc], label_used([Fail|Vls], St));
-opt([{label,Lbl}=I|Is], Acc, #st{mlbl=Mlbl}=St0) ->
-    case maps:find(Lbl, Mlbl) of
-	{ok,Lbls} ->
-	    %% Essential to remove the list of labels from the dictionary,
-	    %% since we will rescan the inserted labels.  We MUST rescan.
-	    St = St0#st{mlbl=maps:remove(Lbl, Mlbl)},
-	    insert_labels([Lbl|Lbls], Is, Acc, St);
-	error ->
-	    opt(Is, [I|Acc], St0)
-    end;
+opt([{label,From}=I,{label,To}|Is], Acc, #st{replace=Replace}=St) ->
+    opt([I|Is], Acc, St#st{replace=Replace#{To => From}});
 opt([{jump,{f,_}=X}|[{label,_},{jump,X}|_]=Is], Acc, St) ->
     opt(Is, Acc, St);
 opt([{jump,{f,Lbl}}|[{label,Lbl}|_]=Is], Acc, St) ->
     opt(Is, Acc, St);
-opt([{jump,{f,L}=Lbl}=I|Is], Acc0, #st{mlbl=Mlbl0}=St0) ->
-    %% All labels before this jump instruction should now be
-    %% moved to the location of the jump's target.
-    {Lbls,Acc} = collect_labels(Acc0, St0),
-    St = case Lbls of
-	     [] -> St0;
-	     [_|_] ->
-		 Mlbl = maps_append_list(L, Lbls, Mlbl0),
-		 St0#st{mlbl=Mlbl}
-	 end,
+opt([{jump,{f,L}=Lbl}=I|Is], Acc0, St0) ->
+    %% Replace all labels before this jump instruction into the
+    %% location of the jump's target.
+    {Acc,St} = collect_labels(Acc0, L, St0),
     skip_unreachable(Is, [I|Acc], label_used(Lbl, St));
 %% Optimization: quickly handle some common instructions that don't
 %% have any failure labels and where is_unreachable_after(I) =:= false.
@@ -369,36 +384,72 @@ opt([I|Is], Acc, #st{labels=Used0}=St0) ->
 	true  -> skip_unreachable(Is, [I|Acc], St);
 	false -> opt(Is, [I|Acc], St)
     end;
-opt([], Acc, #st{mlbl=Mlbl}) ->
-    Code = reverse(Acc),
-    insert_fc_labels(Code, Mlbl).
-
-insert_fc_labels([{label,L}=I|Is0], Mlbl) ->
-    case maps:find(L, Mlbl) of
-	error ->
-	    [I|insert_fc_labels(Is0, Mlbl)];
-	{ok,Lbls} ->
-	    Is = [{label,Lb} || Lb <- Lbls] ++ Is0,
-	    [I|insert_fc_labels(Is, maps:remove(L, Mlbl))]
+opt([], Acc, #st{replace=Replace0}) when Replace0 =/= #{} ->
+    Replace = normalize_replace(maps:to_list(Replace0), Replace0, []),
+    beam_utils:replace_labels(Acc, [], Replace, fun(Old) -> Old end);
+opt([], Acc, #st{replace=Replace}) when Replace =:= #{} ->
+    reverse(Acc).
+
+normalize_replace([{From,To0}|Rest], Replace, Acc) ->
+    case Replace of
+        #{To0 := To} ->
+            normalize_replace([{From,To}|Rest], Replace, Acc);
+        _ ->
+            normalize_replace(Rest, Replace, [{From,To0}|Acc])
     end;
-insert_fc_labels([_|_]=Is, _) -> Is.
-
-maps_append_list(K,Vs,M) ->
-    case M of
-        #{K:=Vs0} -> M#{K:=Vs0++Vs}; % same order as dict
-        _ -> M#{K => Vs}
-    end.
+normalize_replace([], _Replace, Acc) ->
+    maps:from_list(Acc).
+
+%% After eliminating a test, it might happen, that a register was only used
+%% in this test. Let's check if that was the case and if it was so, we can
+%% eliminate the load into the register completely.
+opt_useless_loads([{block,_}|_]=Is, L, #st{index={lazy,FIs}}=St) ->
+    opt_useless_loads(Is, L, St#st{index=beam_utils:index_labels(FIs)});
+opt_useless_loads([{block,Block0}|Is], L, #st{index=Index}=St) ->
+    case opt_useless_block_loads(Block0, L, Index) of
+        [] ->
+            opt_useless_loads(Is, L, St);
+        [_|_]=Block ->
+            {[{block,Block}|Is],St}
+    end;
+%% After eliminating the test and useless blocks, it might happen,
+%% that the previous test could also be eliminated.
+%% It might be that the label was already marked as used, even if ultimately,
+%% it never will be - we can't do much about it at that point, though
+opt_useless_loads([{test,_,{f,L},_}=I|Is], L, St) ->
+    case beam_utils:is_pure_test(I) of
+        false ->
+            {[I|Is],St};
+        true ->
+            opt_useless_loads(Is, L, St)
+    end;
+opt_useless_loads(Is, _L, St) ->
+    {Is,St}.
+
+opt_useless_block_loads([{set,[Dst],_,_}=I|Is], L, Index) ->
+    BlockJump = [{block,Is},{jump,{f,L}}],
+    case beam_utils:is_killed(Dst, BlockJump, Index) of
+        true ->
+            %% The register is killed and not used, we can remove the load
+            opt_useless_block_loads(Is, L, Index);
+        false ->
+            [I|opt_useless_block_loads(Is, L, Index)]
+    end;
+opt_useless_block_loads([I|Is], L, Index) ->
+    [I|opt_useless_block_loads(Is, L, Index)];
+opt_useless_block_loads([], _L, _Index) ->
+    [].
 
-collect_labels(Is, #st{entry=Entry}) ->
-    collect_labels_1(Is, Entry, []).
+collect_labels(Is, Label, #st{entry=Entry,replace=Replace} = St) ->
+    collect_labels_1(Is, Label, Entry, Replace, St).
 
-collect_labels_1([{label,Entry}|_]=Is, Entry, Acc) ->
+collect_labels_1([{label,Entry}|_]=Is, _Label, Entry, Acc, St) ->
     %% Never move the entry label.
-    {Acc,Is};
-collect_labels_1([{label,L}|Is], Entry, Acc) ->
-    collect_labels_1(Is, Entry, [L|Acc]);
-collect_labels_1(Is, _Entry, Acc) ->
-    {Acc,Is}.
+    {Is,St#st{replace=Acc}};
+collect_labels_1([{label,L}|Is], Label, Entry, Acc, St) ->
+    collect_labels_1(Is, Label, Entry, Acc#{L => Label}, St);
+collect_labels_1(Is, _Label, _Entry, Acc, St) ->
+    {Is,St#st{replace=Acc}}.
 
 %% label_defined(Is, Label) -> true | false.
 %%  Test whether the label Label is defined at the start of the instruction
@@ -418,13 +469,6 @@ invert_test(is_eq_exact) -> is_ne_exact;
 invert_test(is_ne_exact) -> is_eq_exact;
 invert_test(_) ->           not_possible.
 
-insert_labels([L|Ls], Is, [{jump,{f,L}}|Acc], St) ->
-    insert_labels(Ls, [{label,L}|Is], Acc, St);
-insert_labels([L|Ls], Is, Acc, St) ->
-    insert_labels(Ls, [{label,L}|Is], Acc, St);
-insert_labels([], Is, Acc, St) ->
-    opt(Is, Acc, St).
-
 %% skip_unreachable([Instruction], St).
 %%  Remove all instructions (including definitions of labels
 %%  that have not been referenced yet) up to the next
diff --git a/lib/compiler/src/beam_listing.erl b/lib/compiler/src/beam_listing.erl
index 836378727b..73c6501fe5 100644
--- a/lib/compiler/src/beam_listing.erl
+++ b/lib/compiler/src/beam_listing.erl
@@ -23,7 +23,6 @@
 
 -include("core_parse.hrl").
 -include("v3_kernel.hrl").
--include("v3_life.hrl").
 -include("beam_disasm.hrl").
 
 -import(lists, [foreach/2]).
@@ -31,7 +30,6 @@
 -type code() :: cerl:c_module()
               | beam_utils:module_code()
               | #k_mdef{}
-              | {module(),_,_,_}                %v3_life
               | [_].                            %form-based format
 
 -spec module(file:io_device(), code()) -> 'ok'.
@@ -43,13 +41,9 @@ module(File, #k_mdef{}=Kern) ->
     %% This is a kernel module.
     io:put_chars(File, v3_kernel_pp:format(Kern));
     %%io:put_chars(File, io_lib:format("~p~n", [Kern]));
-module(File, {Mod,Exp,Attr,Kern}) ->
-    %% This is output from beam_life (v3).
-    io:fwrite(File, "~w.~n~p.~n~p.~n", [Mod,Exp,Attr]),
-    foreach(fun (F) -> function(File, F) end, Kern);
 module(Stream, {Mod,Exp,Attr,Code,NumLabels}) ->
-    %% This is output from beam_codegen.
-    io:format(Stream, "{module, ~p}.  %% version = ~w\n", 
+    %% This is output from v3_codegen.
+    io:format(Stream, "{module, ~p}.  %% version = ~w\n",
 	      [Mod, beam_opcodes:format_number()]),
     io:format(Stream, "\n{exports, ~p}.\n", [Exp]),
     io:format(Stream, "\n{attributes, ~p}.\n", [Attr]),
@@ -60,19 +54,6 @@ module(Stream, {Mod,Exp,Attr,Code,NumLabels}) ->
 			[Name, Arity, Entry]),
 	      io:put_chars(Stream, format_asm(Asm))
       end, Code);
-module(Stream, Code) when is_binary(Code) ->
-    #beam_file{ module = Module, compile_info = CInfo } = beam_disasm:file(Code),
-    Loaded = code:is_loaded(Module),
-    Sticky = code:is_sticky(Module),
-    [code:unstick_mod(Module) || Sticky],
-
-    {module, Module} = code:load_binary(Module, proplists:get_value(source, CInfo), Code),
-    ok = erts_debug:df(Stream, Module),
-
-    %% Restore loaded module
-    _ = [{module, Module} = code:load_file(Module) || Loaded =/= false],
-    [code:stick_mod(Module) || Sticky],
-    ok;
 module(Stream, [_|_]=Fs) ->
     %% Form-based abstract format.
     foreach(fun (F) -> io:format(Stream, "~p.\n", [F]) end, Fs).
@@ -82,60 +63,3 @@ format_asm([{label,L}|Is]) ->
 format_asm([I|Is]) ->
     [io_lib:format("    ~p", [I]),".\n"|format_asm(Is)];
 format_asm([]) -> [].
-
-function(File, {function,Name,Arity,Args,Body,Vdb,_Anno}) ->
-    io:nl(File),
-    io:format(File, "function ~p/~p.\n", [Name,Arity]),
-    io:format(File, " ~p.\n", [Args]),
-    print_vdb(File, Vdb),
-    put(beam_listing_nl, false),
-    nl(File),
-    foreach(fun(F) -> format(File, F, []) end, Body),
-    nl(File),
-    erase(beam_listing_nl).
-
-format(File, #l{ke=Ke,i=I,vdb=Vdb}, Ind) ->
-    nl(File),
-    ind_format(File, Ind, "~p ", [I]),
-    print_vdb(File, Vdb),
-    nl(File),
-    format(File, Ke, Ind);
-format(File, Tuple, Ind) when is_tuple(Tuple) ->
-    ind_format(File, Ind, "{", []),
-    format_list(File, tuple_to_list(Tuple), [$\s|Ind]),
-    ind_format(File, Ind, "}", []);
-format(File, List, Ind) when is_list(List) ->
-    ind_format(File, Ind, "[", []),
-    format_list(File, List, [$\s|Ind]),
-    ind_format(File, Ind, "]", []);
-format(File, F, Ind) ->
-    ind_format(File, Ind, "~p", [F]).
-
-format_list(File, [F], Ind) ->
-    format(File, F, Ind);
-format_list(File, [F|Fs], Ind) ->
-    format(File, F, Ind),
-    ind_format(File, Ind, ",", []),
-    format_list(File, Fs, Ind);
-format_list(_, [], _) -> ok.
-
-
-print_vdb(File, [{Var,F,E}|Vs]) ->
-    io:format(File, "~p:~p..~p ", [Var,F,E]),
-    print_vdb(File, Vs);
-print_vdb(_, []) -> ok.
-
-ind_format(File, Ind, Format, Args) ->
-    case get(beam_listing_nl) of
-	true ->
-	    put(beam_listing_nl, false),
-	    io:put_chars(File, Ind);
-	false -> ok
-    end,
-    io:format(File, Format, Args).
-    
-nl(File) ->
-    case put(beam_listing_nl, true) of
-	true -> ok;
-	false -> io:nl(File)
-    end.
diff --git a/lib/compiler/src/beam_peep.erl b/lib/compiler/src/beam_peep.erl
index 6df5c02334..eb3192fe8f 100644
--- a/lib/compiler/src/beam_peep.erl
+++ b/lib/compiler/src/beam_peep.erl
@@ -41,8 +41,7 @@ function({function,Name,Arity,CLabel,Is0}) ->
 	Is = beam_jump:remove_unused_labels(Is1),
 	{function,Name,Arity,CLabel,Is}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [Name,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
@@ -89,15 +88,37 @@ peep([{gc_bif,_,_,_,_,Dst}=I|Is], SeenTests0, Acc) ->
 peep([{jump,{f,L}},{label,L}=I|Is], _, Acc) ->
     %% Sometimes beam_jump has missed this optimization.
     peep(Is, gb_sets:empty(), [I|Acc]);
-peep([{select,Op,R,F,Vls0}|Is], _, Acc) ->
+peep([{select,Op,R,F,Vls0}|Is], SeenTests0, Acc0) ->
     case prune_redundant_values(Vls0, F) of
 	[] ->
 	    %% No values left. Must convert to plain jump.
 	    I = {jump,F},
-	    peep(Is, gb_sets:empty(), [I|Acc]);
+	    peep([I|Is], gb_sets:empty(), Acc0);
+        [{atom,_}=Value,Lbl] when Op =:= select_val ->
+            %% Single value left. Convert to regular test and pop redundant tests.
+            Is1 = [{test,is_eq_exact,F,[R,Value]},{jump,Lbl}|Is],
+            case Acc0 of
+                [{test,is_atom,F,[R]}|Acc] ->
+                    peep(Is1, SeenTests0, Acc);
+                _ ->
+                    peep(Is1, SeenTests0, Acc0)
+            end;
+        [{integer,_}=Value,Lbl] when Op =:= select_val ->
+            %% Single value left. Convert to regular test and pop redundant tests.
+            Is1 = [{test,is_eq_exact,F,[R,Value]},{jump,Lbl}|Is],
+            case Acc0 of
+                [{test,is_integer,F,[R]}|Acc] ->
+                    peep(Is1, SeenTests0, Acc);
+                _ ->
+                    peep(Is1, SeenTests0, Acc0)
+            end;
+        [Arity,Lbl] when Op =:= select_tuple_arity ->
+            %% Single value left. Convert to regular test
+            Is1 = [{test,test_arity,F,[R,Arity]},{jump,Lbl}|Is],
+            peep(Is1, SeenTests0, Acc0);
 	[_|_]=Vls ->
 	    I = {select,Op,R,F,Vls},
-	    peep(Is, gb_sets:empty(), [I|Acc])
+	    peep(Is, gb_sets:empty(), [I|Acc0])
     end;
 peep([{test,Op,_,Ops}=I|Is], SeenTests0, Acc) ->
     case beam_utils:is_pure_test(I) of
diff --git a/lib/compiler/src/beam_receive.erl b/lib/compiler/src/beam_receive.erl
index 1403e1e05e..3c8efa577c 100644
--- a/lib/compiler/src/beam_receive.erl
+++ b/lib/compiler/src/beam_receive.erl
@@ -82,8 +82,7 @@ function({function,Name,Arity,Entry,Is}) ->
 	D = beam_utils:index_labels(Is),
 	{function,Name,Arity,Entry,opt(Is, D, [])}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [Name,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
@@ -207,6 +206,8 @@ opt_update_regs({label,Lbl}, R, L) ->
 	    %% A catch label for a previously seen catch instruction is OK.
 	    {R,L}
     end;
+opt_update_regs({'try',_,{f,Lbl}}, R, L) ->
+    {R,gb_sets:add(Lbl, L)};
 opt_update_regs({try_end,_}, R, L) ->
     {R,L};
 opt_update_regs({line,_}, R, L) ->
diff --git a/lib/compiler/src/beam_record.erl b/lib/compiler/src/beam_record.erl
index 419089b1bc..db1053e48c 100644
--- a/lib/compiler/src/beam_record.erl
+++ b/lib/compiler/src/beam_record.erl
@@ -15,19 +15,12 @@
 %%
 %% %CopyrightEnd%
 %%
-%% File:    beam_record.erl
-%% Author:  Björn-Egil Dahlberg
-%% Created: 2014-09-03
-%%
-
--module(beam_record).
--export([module/2]).
 
 %% Rewrite the instruction stream on tagged tuple tests.
-%% Tagged tuples means a tuple of any arity with an atom as its first element.
-%% Typically records, ok-tuples and error-tuples.
-%% 
-%% from:
+%% Tagged tuples means a tuple of any arity with an atom as its
+%% first element, such as records and error tuples.
+%%
+%% From:
 %%     ...
 %%     {test,is_tuple,Fail,[Src]}.
 %%     {test,test_arity,Fail,[Src,Sz]}.
@@ -36,13 +29,16 @@
 %%     ...
 %%     {test,is_eq_exact,Fail,[Dst,Atom]}.
 %%     ...
-%% to:
+%% To:
 %%     ...
 %%     {test,is_tagged_tuple,Fail,[Src,Sz,Atom]}.
 %%     ...
+%%
 
+-module(beam_record).
+-export([module/2]).
 
--import(lists, [reverse/1]).
+-import(lists, [reverse/1,reverse/2]).
 
 -spec module(beam_utils:module_code(), [compile:option()]) ->
                     {'ok',beam_utils:module_code()}.
@@ -51,56 +47,85 @@ module({Mod,Exp,Attr,Fs0,Lc}, _Opt) ->
     Fs = [function(F) || F <- Fs0],
     {ok,{Mod,Exp,Attr,Fs,Lc}}.
 
-function({function,Name,Arity,CLabel,Is}) ->
+function({function,Name,Arity,CLabel,Is0}) ->
     try
-        Idx = beam_utils:index_labels(Is),
-        {function,Name,Arity,CLabel,rewrite(Is,Idx)}
+        Is1 = beam_utils:anno_defs(Is0),
+        Idx = beam_utils:index_labels(Is1),
+        Is = rewrite(reverse(Is1), Idx),
+        {function,Name,Arity,CLabel,Is}
     catch
-        Class:Error ->
-            Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
             io:fwrite("Function: ~w/~w\n", [Name,Arity]),
             erlang:raise(Class, Error, Stack)
     end.
 
-rewrite(Is,Idx) ->
-    rewrite(Is,Idx,[]).
+rewrite(Is, Idx) ->
+    rewrite(Is, Idx, 0, []).
 
-rewrite([{test,is_tuple,Fail,[Src]}=I1,
-         {test,test_arity,Fail,[Src,N]}=I2|Is],Idx,Acc) ->
-    case is_tagged_tuple(Is,Fail,Src,Idx) of
+rewrite([{test,test_arity,Fail,[Src,N]}=TA,
+         {test,is_tuple,Fail,[Src]}=TT|Is], Idx, Def, Acc0) ->
+    case is_tagged_tuple(Acc0, Def, Fail, Src, Idx) of
         no ->
-            rewrite(Is,Idx,[I2,I1|Acc]);
-        {Atom,[{block,[]}|Is1]} ->
-            rewrite(Is1,Idx,[{test,is_tagged_tuple,Fail,[Src,N,Atom]}|Acc]);
-        {Atom,Is1} ->
-            rewrite(Is1,Idx,[{test,is_tagged_tuple,Fail,[Src,N,Atom]}|Acc])
+            rewrite(Is, Idx, 0, [TT,TA|Acc0]);
+        {yes,Atom,Acc} ->
+            I = {test,is_tagged_tuple,Fail,[Src,N,Atom]},
+            rewrite(Is, Idx, Def, [I|Acc])
     end;
-rewrite([I|Is],Idx,Acc) ->
-    rewrite(Is,Idx,[I|Acc]);
-rewrite([],_,Acc) -> reverse(Acc).
-
-is_tagged_tuple([{block,[{set,[Dst],[Src],{get_tuple_element,0}}=B|Bs]},
-                 {test,is_eq_exact,Fail,[Dst,{atom,_}=Atom]}|Is],Fail,Src,Idx) ->
+rewrite([{block,[{'%def',Def}|Bl]}|Is], Idx, _Def, Acc) ->
+    rewrite(Is, Idx, Def, [{block,Bl}|Acc]);
+rewrite([{label,L}=I|Is], Idx0, Def, Acc) ->
+    Idx = beam_utils:index_label(L, Acc, Idx0),
+    rewrite(Is, Idx, Def, [I|Acc]);
+rewrite([I|Is], Idx, Def, Acc) ->
+    rewrite(Is, Idx, Def, [I|Acc]);
+rewrite([], _, _, Acc) -> Acc.
 
-    %% if Dst is killed in the instruction stream and at fail label,
-    %% we can safely remove get_tuple_element.
-    %%
-    %% if Dst is not killed in the stream, we cannot remove get_tuple_element
-    %% since it is referenced.
-
-    case is_killed(Dst,Is,Fail,Idx) of
-        true  -> {Atom,[{block,Bs}|Is]};
-        false -> {Atom,[{block,[B|Bs]}|Is]}
+is_tagged_tuple([{block,Bl},
+                 {test,is_eq_exact,Fail,[Dst,{atom,_}=Atom]}|Is],
+                Def, Fail, Src, Idx) ->
+    case is_tagged_tuple_1(Bl, Is, Fail, Src, Dst, Idx, Def, []) of
+        no ->
+            no;
+        {yes,[]} ->
+            {yes,Atom,Is};
+        {yes,[_|_]=Block} ->
+            {yes,Atom,[{block,Block}|Is]}
     end;
-is_tagged_tuple([{block,[{set,_,_,_}=B|Bs]},
-                 {test,is_eq_exact,_,_}=I|Is],Fail,Src,Idx) ->
-    case is_tagged_tuple([{block,Bs},I|Is],Fail,Src,Idx) of
-        {Atom,[{block,Bsr}|Isr]} -> {Atom,[{block,[B|Bsr]}|Isr]};
-        no                       -> no
+is_tagged_tuple(_, _, _, _, _) ->
+    no.
+
+is_tagged_tuple_1([{set,[Dst],[Src],{get_tuple_element,0}}=I|Bl],
+                  Is, Fail, Src, Dst, Idx, Def, Acc) ->
+    %% Check usage of Dst to find out whether the get_tuple_element
+    %% is needed.
+    case usage(Dst, Is, Fail, Idx) of
+        killed ->
+            %% Safe to remove the get_tuple_element instruction.
+            {yes,reverse(Acc, Bl)};
+        used ->
+            %% Actively used. Must keep instruction.
+            {yes,reverse(Acc, [I|Bl])};
+        not_used ->
+            %% Not actually used (but must be initialized).
+            case is_defined(Dst, Def) of
+                false ->
+                    %% Dst must be initialized, but the
+                    %% actual value does not matter.
+                    Kill = {set,[Dst],[nil],move},
+                    {yes,reverse(Acc, [Kill|Bl])};
+                true ->
+                    %% The register is previously initialized.
+                    %% We can remove the instruction.
+                    {yes,reverse(Acc, Bl)}
+            end
     end;
-is_tagged_tuple(_Is,_Fail,_Src,_Idx) ->
+is_tagged_tuple_1([I|Bl], Is, Fail, Src, Dst, Idx, Def, Acc) ->
+    is_tagged_tuple_1(Bl, Is, Fail, Src, Dst, Idx, Def, [I|Acc]);
+is_tagged_tuple_1(_, _, _, _, _, _, _, _) ->
     no.
 
-is_killed(Dst,Is,{_,Lbl},Idx) ->
-    beam_utils:is_killed(Dst,Is,Idx) andalso
-        beam_utils:is_killed_at(Dst,Lbl,Idx).
+usage(Dst, Is, Fail, Idx) ->
+    beam_utils:usage(Dst, [{test,is_number,Fail,[nil]}|Is], Idx).
+
+is_defined({x,X}, Def) ->
+    (Def bsr X) band 1 =:= 1.
diff --git a/lib/compiler/src/beam_reorder.erl b/lib/compiler/src/beam_reorder.erl
index 910b7f6b0a..63bb57a1ac 100644
--- a/lib/compiler/src/beam_reorder.erl
+++ b/lib/compiler/src/beam_reorder.erl
@@ -35,8 +35,7 @@ function({function,Name,Arity,CLabel,Is0}) ->
 	Is = reorder(Is0),
 	{function,Name,Arity,CLabel,Is}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [Name,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
diff --git a/lib/compiler/src/beam_type.erl b/lib/compiler/src/beam_type.erl
index 3d842a6fd3..16d5a36447 100644
--- a/lib/compiler/src/beam_type.erl
+++ b/lib/compiler/src/beam_type.erl
@@ -43,8 +43,7 @@ function({function,Name,Arity,CLabel,Asm0}) ->
 	Asm = beam_utils:delete_live_annos(Asm3),
 	{function,Name,Arity,CLabel,Asm}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [Name,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
diff --git a/lib/compiler/src/beam_utils.erl b/lib/compiler/src/beam_utils.erl
index e39fbdc3b7..e61d6a43b4 100644
--- a/lib/compiler/src/beam_utils.erl
+++ b/lib/compiler/src/beam_utils.erl
@@ -22,15 +22,23 @@
 
 -module(beam_utils).
 -export([is_killed_block/2,is_killed/3,is_killed_at/3,
-	 is_not_used/3,
-	 empty_label_index/0,index_label/3,index_labels/1,
+	 is_not_used/3,usage/3,
+	 empty_label_index/0,index_label/3,index_labels/1,replace_labels/4,
 	 code_at/2,bif_to_test/3,is_pure_test/1,
 	 live_opt/1,delete_live_annos/1,combine_heap_needs/2,
-	 split_even/1]).
+         anno_defs/1,
+	 split_even/1
+        ]).
 
 -export_type([code_index/0,module_code/0,instruction/0]).
 
--import(lists, [member/2,sort/1,reverse/1,splitwith/2]).
+-import(lists, [flatmap/2,map/2,member/2,sort/1,reverse/1,splitwith/2]).
+
+-define(is_const(Val), (Val =:= nil orelse
+                        element(1, Val) =:= integer orelse
+                        element(1, Val) =:= float orelse
+                        element(1, Val) =:= atom orelse
+                        element(1, Val) =:= literal)).
 
 %% instruction() describes all instructions that are used during optimzation
 %% (from beam_a to beam_z).
@@ -54,6 +62,23 @@
 	{lbl :: code_index(),            %Label to code index.
 	 res :: result_cache()}).        %Result cache for each label.
 
+%% usage(Register, [Instruction], State) -> killed|not_used|used.
+%%  Determine the usage of Register in the instruction sequence.
+%%  The return value is one of:
+%%
+%%  killed   - The register is not used in any way.
+%%  not_used - The register is referenced only by an allocating instruction
+%%             (the actual value does not matter).
+%%  used     - The register is used (its value do matter).
+
+-spec usage(beam_asm:reg(), [instruction()], code_index()) ->
+  'killed' | 'not_used' | 'used'.
+
+usage(R, Is, D) ->
+    St = #live{lbl=D,res=gb_trees:empty()},
+    {Usage,_} = check_liveness(R, Is, St),
+    Usage.
+
 
 %% is_killed_block(Register, [Instruction]) -> true|false
 %%  Determine whether a register is killed by the instruction sequence inside
@@ -160,6 +185,18 @@ index_label(Lbl, Is0, Acc) ->
 code_at(L, Ll) ->
     gb_trees:get(L, Ll).
 
+%% replace_labels(FunctionIs, Tail, ReplaceDb, Fallback) -> FunctionIs.
+%%  Replace all labels in instructions according to the ReplaceDb.
+%%  If label is not found the Fallback is called with the label to
+%%  produce a new one.
+
+-spec replace_labels([instruction()],
+                     [instruction()],
+                     #{beam_asm:label() => beam_asm:label()},
+                     fun((beam_asm:label()) -> term())) -> [instruction()].
+replace_labels(Is, Acc, D, Fb) ->
+    replace_labels_1(Is, Acc, D, Fb).
+
 %% bif_to_test(Bif, [Op], Fail) -> {test,Test,Fail,[Op]}
 %%  Convert a BIF to a test. Fail if not possible.
 
@@ -185,10 +222,20 @@ bif_to_test('>', [A,B], Fail) -> {test,is_lt,Fail,[B,A]};
 bif_to_test('<', [_,_]=Ops, Fail) -> {test,is_lt,Fail,Ops};
 bif_to_test('>=', [_,_]=Ops, Fail) -> {test,is_ge,Fail,Ops};
 bif_to_test('==', [A,nil], Fail) -> {test,is_nil,Fail,[A]};
+bif_to_test('==', [nil,A], Fail) -> {test,is_nil,Fail,[A]};
+bif_to_test('==', [C,A], Fail) when ?is_const(C) ->
+    {test,is_eq,Fail,[A,C]};
 bif_to_test('==', [_,_]=Ops, Fail) -> {test,is_eq,Fail,Ops};
+bif_to_test('/=', [C,A], Fail) when ?is_const(C) ->
+    {test,is_ne,Fail,[A,C]};
 bif_to_test('/=', [_,_]=Ops, Fail) -> {test,is_ne,Fail,Ops};
 bif_to_test('=:=', [A,nil], Fail) -> {test,is_nil,Fail,[A]};
+bif_to_test('=:=', [nil,A], Fail) -> {test,is_nil,Fail,[A]};
+bif_to_test('=:=', [C,A], Fail) when ?is_const(C) ->
+    {test,is_eq_exact,Fail,[A,C]};
 bif_to_test('=:=', [_,_]=Ops, Fail) -> {test,is_eq_exact,Fail,Ops};
+bif_to_test('=/=', [C,A], Fail) when ?is_const(C) ->
+    {test,is_ne_exact,Fail,[A,C]};
 bif_to_test('=/=', [_,_]=Ops, Fail) -> {test,is_ne_exact,Fail,Ops};
 bif_to_test(is_record, [_,_,_]=Ops, Fail) -> {test,is_record,Fail,Ops}.
 
@@ -254,16 +301,33 @@ delete_live_annos([]) -> [].
 %% combine_heap_needs(HeapNeed1, HeapNeed2) -> HeapNeed
 %%  Combine the heap need for two allocation instructions.
 
--spec combine_heap_needs(term(), term()) -> term().
+-type heap_need_tag() :: 'floats' | 'words'.
+-type heap_need() :: non_neg_integer() |
+                     {'alloc',[{heap_need_tag(),non_neg_integer()}]}.
+-spec combine_heap_needs(heap_need(), heap_need()) -> heap_need().
 
-combine_heap_needs({alloc,Alloc1}, {alloc,Alloc2}) ->
-    {alloc,combine_alloc_lists(Alloc1, Alloc2)};
-combine_heap_needs({alloc,Alloc}, Words) when is_integer(Words) ->
-    {alloc,combine_alloc_lists(Alloc, [{words,Words}])};
-combine_heap_needs(Words, {alloc,Alloc}) when is_integer(Words) ->
-    {alloc,combine_alloc_lists(Alloc, [{words,Words}])};
 combine_heap_needs(H1, H2) when is_integer(H1), is_integer(H2) ->
-    H1+H2.
+    H1 + H2;
+combine_heap_needs(H1, H2) ->
+    combine_alloc_lists([H1,H2]).
+
+
+%% anno_defs(Instructions) -> Instructions'
+%%  Add {'%def',RegisterBitmap} annotations to the beginning of
+%%  each block.  Iff bit X is set in the the bitmap, it means
+%%  that {x,X} is defined when the block is entered.
+
+-spec anno_defs([instruction()]) -> [instruction()].
+
+anno_defs(Is0) ->
+    {Bef,[Fi|Is1]} =
+	splitwith(fun({func_info,_,_,_}) -> false;
+		     (_) -> true
+		  end, Is0),
+    {func_info,_,_,Arity} = Fi,
+    Regs = init_def_regs(Arity),
+    Is = defs(Is1, Regs, #{}),
+    Bef ++ [Fi|Is].
 
 %% split_even/1
 %% [1,2,3,4,5,6] -> {[1,3,5],[2,4,6]}
@@ -272,7 +336,6 @@ combine_heap_needs(H1, H2) when is_integer(H1), is_integer(H2) ->
 
 split_even(Rs) -> split_even(Rs, [], []).
 
-
 %%%
 %%% Local functions.
 %%%
@@ -290,6 +353,10 @@ check_liveness(R, [{block,Blk}|Is], St0) ->
     case check_liveness_block(R, Blk, St0) of
 	{transparent,St1} ->
 	    check_liveness(R, Is, St1);
+	{alloc_used,St1} ->
+            %% Used by an allocating instruction, but value not referenced.
+            %% Must check the rest of the instructions.
+	    not_used(check_liveness(R, Is, St1));
 	{Other,_}=Res when is_atom(Other) ->
 	    Res
     end;
@@ -348,9 +415,16 @@ check_liveness(R, [{bs_init,_,_,none,Ss,Dst}|Is], St) ->
 check_liveness(R, [{bs_init,_,_,Live,Ss,Dst}|Is], St) ->
     case R of
 	{x,X} ->
-	    case X < Live orelse member(R, Ss) of
-		true -> {used,St};
-		false -> {killed,St}
+            case member(R, Ss) of
+                true ->
+                    {used,St};
+                false ->
+                    if
+                        X < Live ->
+                            not_used(check_liveness(R, Is, St));
+                        true ->
+                            {killed,St}
+                    end
 	    end;
 	{y,_} ->
 	    case member(R, Ss) of
@@ -560,7 +634,7 @@ check_liveness_ret(R, R, St) -> {used,St};
 check_liveness_ret(_, _, St) -> {killed,St}.
 
 %% check_liveness_block(Reg, [Instruction], State) ->
-%%     {killed | not_used | used | transparent,State'}
+%%     {killed | not_used | used | alloc_used | transparent,State'}
 %%  Finds out how Reg is used in the instruction sequence inside a block.
 %%  Returns one of:
 %%    killed - Reg is assigned a new value or killed by an
@@ -568,6 +642,7 @@ check_liveness_ret(_, _, St) -> {killed,St}.
 %%    not_used - The value is not used, but the register is referenced
 %%       e.g. by an allocation instruction
 %%    transparent - Reg is neither used nor killed
+%%    alloc_used - Used only in an allocate instruction
 %%    used - Reg is explicitly used by an instruction
 %%
 %%  '%live' annotations are not allowed.
@@ -581,7 +656,7 @@ check_liveness_block({x,X}=R, [{set,Ds,Ss,{alloc,Live,Op}}|Is], St0) ->
 	true ->
 	    case check_liveness_block_1(R, Ss, Ds, Op, Is, St0) of
 		{killed,St} -> {not_used,St};
-		{transparent,St} -> {not_used,St};
+                {transparent,St} -> {alloc_used,St};
 		{_,_}=Res -> Res
 	    end
     end;
@@ -643,22 +718,70 @@ index_labels_1([], Acc) -> gb_trees:from_orddict(sort(Acc)).
 drop_labels([{label,_}|Is]) -> drop_labels(Is);
 drop_labels(Is) -> Is.
 
-%% Help functions for combine_heap_needs.
 
-combine_alloc_lists(Al1, Al2) ->
-    combine_alloc_lists_1(sort(Al1++Al2)).
+replace_labels_1([{test,Test,{f,Lbl},Ops}|Is], Acc, D, Fb) ->
+    replace_labels_1(Is, [{test,Test,{f,label(Lbl, D, Fb)},Ops}|Acc], D, Fb);
+replace_labels_1([{test,Test,{f,Lbl},Live,Ops,Dst}|Is], Acc, D, Fb) ->
+    replace_labels_1(Is, [{test,Test,{f,label(Lbl, D, Fb)},Live,Ops,Dst}|Acc], D, Fb);
+replace_labels_1([{select,I,R,{f,Fail0},Vls0}|Is], Acc, D, Fb) ->
+    Vls = map(fun ({f,L}) -> {f,label(L, D, Fb)};
+		   (Other) -> Other
+	      end, Vls0),
+    Fail = label(Fail0, D, Fb),
+    replace_labels_1(Is, [{select,I,R,{f,Fail},Vls}|Acc], D, Fb);
+replace_labels_1([{'try',R,{f,Lbl}}|Is], Acc, D, Fb) ->
+    replace_labels_1(Is, [{'try',R,{f,label(Lbl, D, Fb)}}|Acc], D, Fb);
+replace_labels_1([{'catch',R,{f,Lbl}}|Is], Acc, D, Fb) ->
+    replace_labels_1(Is, [{'catch',R,{f,label(Lbl, D, Fb)}}|Acc], D, Fb);
+replace_labels_1([{jump,{f,Lbl}}|Is], Acc, D, Fb) ->
+    replace_labels_1(Is, [{jump,{f,label(Lbl, D, Fb)}}|Acc], D, Fb);
+replace_labels_1([{loop_rec,{f,Lbl},R}|Is], Acc, D, Fb) ->
+    replace_labels_1(Is, [{loop_rec,{f,label(Lbl, D, Fb)},R}|Acc], D, Fb);
+replace_labels_1([{loop_rec_end,{f,Lbl}}|Is], Acc, D, Fb) ->
+    replace_labels_1(Is, [{loop_rec_end,{f,label(Lbl, D, Fb)}}|Acc], D, Fb);
+replace_labels_1([{wait,{f,Lbl}}|Is], Acc, D, Fb) ->
+    replace_labels_1(Is, [{wait,{f,label(Lbl, D, Fb)}}|Acc], D, Fb);
+replace_labels_1([{wait_timeout,{f,Lbl},To}|Is], Acc, D, Fb) ->
+    replace_labels_1(Is, [{wait_timeout,{f,label(Lbl, D, Fb)},To}|Acc], D, Fb);
+replace_labels_1([{bif,Name,{f,Lbl},As,R}|Is], Acc, D, Fb) when Lbl =/= 0 ->
+    replace_labels_1(Is, [{bif,Name,{f,label(Lbl, D, Fb)},As,R}|Acc], D, Fb);
+replace_labels_1([{gc_bif,Name,{f,Lbl},Live,As,R}|Is], Acc, D, Fb) when Lbl =/= 0 ->
+    replace_labels_1(Is, [{gc_bif,Name,{f,label(Lbl, D, Fb)},Live,As,R}|Acc], D, Fb);
+replace_labels_1([{call,Ar,{f,Lbl}}|Is], Acc, D, Fb) ->
+    replace_labels_1(Is, [{call,Ar,{f,label(Lbl, D, Fb)}}|Acc], D, Fb);
+replace_labels_1([{make_fun2,{f,Lbl},U1,U2,U3}|Is], Acc, D, Fb) ->
+    replace_labels_1(Is, [{make_fun2,{f,label(Lbl, D, Fb)},U1,U2,U3}|Acc], D, Fb);
+replace_labels_1([{bs_init,{f,Lbl},Info,Live,Ss,Dst}|Is], Acc, D, Fb) when Lbl =/= 0 ->
+    replace_labels_1(Is, [{bs_init,{f,label(Lbl, D, Fb)},Info,Live,Ss,Dst}|Acc], D, Fb);
+replace_labels_1([{bs_put,{f,Lbl},Info,Ss}|Is], Acc, D, Fb) when Lbl =/= 0 ->
+    replace_labels_1(Is, [{bs_put,{f,label(Lbl, D, Fb)},Info,Ss}|Acc], D, Fb);
+replace_labels_1([{put_map=I,{f,Lbl},Op,Src,Dst,Live,List}|Is], Acc, D, Fb)
+  when Lbl =/= 0 ->
+    replace_labels_1(Is, [{I,{f,label(Lbl, D, Fb)},Op,Src,Dst,Live,List}|Acc], D, Fb);
+replace_labels_1([{get_map_elements=I,{f,Lbl},Src,List}|Is], Acc, D, Fb) when Lbl =/= 0 ->
+    replace_labels_1(Is, [{I,{f,label(Lbl, D, Fb)},Src,List}|Acc], D, Fb);
+replace_labels_1([I|Is], Acc, D, Fb) ->
+    replace_labels_1(Is, [I|Acc], D, Fb);
+replace_labels_1([], Acc, _, _) -> Acc.
+
+label(Old, D, Fb) ->
+    case D of
+        #{Old := New} -> New;
+        _ -> Fb(Old)
+    end.
 
-combine_alloc_lists_1([{words,W1},{words,W2}|T])
-  when is_integer(W1), is_integer(W2) ->
-    [{words,W1+W2}|combine_alloc_lists_1(T)];
-combine_alloc_lists_1([{floats,F1},{floats,F2}|T])
-  when is_integer(F1), is_integer(F2) ->
-    [{floats,F1+F2}|combine_alloc_lists_1(T)];
-combine_alloc_lists_1([{words,_}=W|T]) ->
-    [W|combine_alloc_lists_1(T)];
-combine_alloc_lists_1([{floats,_}=F|T]) ->
-    [F|combine_alloc_lists_1(T)];
-combine_alloc_lists_1([]) -> [].
+%% Help function for combine_heap_needs.
+
+combine_alloc_lists(Al0) ->
+    Al1 = flatmap(fun(Words) when is_integer(Words) ->
+                         [{words,Words}];
+                    ({alloc,List}) ->
+                         List
+                 end, Al0),
+    Al2 = sofs:relation(Al1),
+    Al3 = sofs:relation_to_family(Al2),
+    Al4 = sofs:to_external(Al3),
+    [{Tag,lists:sum(L)} || {Tag,L} <- Al4].
 
 %% live_opt/4.
 
@@ -701,6 +824,8 @@ live_opt([{block,Bl0}|Is], Regs0, D, Acc) ->
     {Bl,Regs} = live_opt_block(reverse(Bl0), Regs0, D, [Live0]),
     Live = {'%live',live_regs(Regs),Regs},
     live_opt(Is, Regs, D, [{block,[Live|Bl]}|Acc]);
+live_opt([build_stacktrace=I|Is], _, D, Acc) ->
+    live_opt(Is, live_call(1), D, [I|Acc]);
 live_opt([{label,L}=I|Is], Regs, D0, Acc) ->
     D = gb_trees:insert(L, Regs, D0),
     live_opt(Is, Regs, D, [I|Acc]);
@@ -746,8 +871,14 @@ live_opt([{select,_,Src,Fail,List}=I|Is], Regs0, D, Acc) ->
     Regs1 = x_live([Src], Regs0),
     Regs = live_join_labels([Fail|List], D, Regs1),
     live_opt(Is, Regs, D, [I|Acc]);
-live_opt([{try_case,_}=I|Is], _, D, Acc) ->
-    live_opt(Is, live_call(1), D, [I|Acc]);
+live_opt([{try_case,Y}=I|Is], Regs0, D, Acc) ->
+    Regs = live_call(1),
+    case Regs0 of
+        0 ->
+            live_opt(Is, Regs, D, [{try_end,Y}|Acc]);
+        _ ->
+            live_opt(Is, live_call(1), D, [I|Acc])
+    end;
 live_opt([{loop_rec,_Fail,_Dst}=I|Is], _, D, Acc) ->
     live_opt(Is, 0, D, [I|Acc]);
 live_opt([timeout=I|Is], _, D, Acc) ->
@@ -865,3 +996,208 @@ split_even([], Ss, Ds) ->
     {reverse(Ss),reverse(Ds)};
 split_even([S,D|Rs], Ss, Ds) ->
     split_even(Rs, [S|Ss], [D|Ds]).
+
+%%%
+%%% Add annotations for defined registers.
+%%%
+%%% This analysis is done by scanning the instructions in
+%%% execution order.
+%%%
+
+defs([{apply,_}=I|Is], _Regs, D) ->
+    [I|defs(Is, 1, D)];
+defs([{bif,_,{f,Fail},_Src,Dst}=I|Is], Regs0, D) ->
+    Regs = def_regs([Dst], Regs0),
+    [I|defs(Is, Regs, update_regs(Fail, Regs0, D))];
+defs([{block,Block0}|Is], Regs0, D0) ->
+    {Block,Regs,D} = defs_list(Block0, Regs0, D0),
+    [{block,[{'%def',Regs0}|Block]}|defs(Is, Regs, D)];
+defs([{bs_init,{f,L},_,_,_,Dst}=I|Is], Regs0, D) ->
+    Regs = def_regs([Dst], Regs0),
+    [I|defs(Is, Regs, update_regs(L, Regs, D))];
+defs([{bs_put,{f,L},_,_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, update_regs(L, Regs, D))];
+defs([build_stacktrace=I|Is], _Regs, D) ->
+    [I|defs(Is, 1, D)];
+defs([{call,_,_}=I|Is], _Regs, D) ->
+    [I|defs(Is, 1, D)];
+defs([{call_ext,_,{extfunc,M,F,A}}=I|Is], _Regs, D) ->
+    case erl_bifs:is_exit_bif(M, F, A) of
+        false ->
+            [I|defs(Is, 1, D)];
+        true ->
+            [I|defs_unreachable(Is, D)]
+    end;
+defs([{call_ext,_,_}=I|Is], _Regs, D) ->
+    [I|defs(Is, 1, D)];
+defs([{call_fun,_}=I|Is], _Regs, D) ->
+    [I|defs(Is, 1, D)];
+defs([{'catch',_,{f,L}}=I|Is], Regs, D) ->
+    RegsAtLabel = init_def_regs(1),
+    [I|defs(Is, Regs, update_regs(L, RegsAtLabel, D))];
+defs([{catch_end,_}=I|Is], _Regs, D) ->
+    Regs = init_def_regs(1),
+    [I|defs(Is, Regs, D)];
+defs([{gc_bif,_,{f,Fail},Live,_Src,Dst}=I|Is], Regs0, D) ->
+    true = all_defined(Live, Regs0),            %Assertion.
+    Regs = def_regs([Dst], init_def_regs(Live)),
+    [I|defs(Is, Regs, update_regs(Fail, Regs0, D))];
+defs([{get_map_elements,{f,L},_Src,{list,DstList}}=I|Is], Regs0, D) ->
+    {_,Ds} = beam_utils:split_even(DstList),
+    Regs = def_regs(Ds, Regs0),
+    [I|defs(Is, Regs, update_regs(L, Regs0, D))];
+defs([{get_tuple_element,_,_,Dst}=I|Is], Regs0, D) ->
+    Regs = def_regs([Dst], Regs0),
+    [I|defs(Is, Regs, D)];
+defs([{jump,{f,L}}=I|Is], Regs, D) ->
+    [I|defs_unreachable(Is, update_regs(L, Regs, D))];
+defs([{label,L}=I|Is], Regs0, D) ->
+    case D of
+        #{L:=Regs1} ->
+            Regs = Regs0 band Regs1,
+            [I|defs(Is, Regs, D)];
+        #{} ->
+            [I|defs(Is, Regs0, D)]
+    end;
+defs([{loop_rec,{f,L},{x,0}}=I|Is], _Regs, D0) ->
+    RegsAtLabel = init_def_regs(0),
+    D = update_regs(L, RegsAtLabel, D0),
+    [I|defs(Is, init_def_regs(1), D)];
+defs([{loop_rec_end,_}=I|Is], _Regs, D) ->
+    [I|defs(Is, 0, D)];
+defs([{make_fun2,_,_,_,_}=I|Is], _Regs, D) ->
+    [I|defs(Is, 1, D)];
+defs([{move,_,Dst}=I|Is], Regs0, D) ->
+    Regs = def_regs([Dst], Regs0),
+    [I|defs(Is, Regs, D)];
+defs([{put_map,{f,Fail},_,_,Dst,_,_}=I|Is], Regs0, D) ->
+    Regs = def_regs([Dst], Regs0),
+    [I|defs(Is, Regs, update_regs(Fail, Regs0, D))];
+defs([return=I|Is], _Regs, D) ->
+    [I|defs_unreachable(Is, D)];
+defs([{select,_,_Src,Fail,List}=I|Is], Regs, D0) ->
+    D = update_list([Fail|List], Regs, D0),
+    [I|defs_unreachable(Is, D)];
+defs([{test,_,{f,L},_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, update_regs(L, Regs, D))];
+defs([{test,_,{f,L},Live,_,Dst}=I|Is], Regs0, D) ->
+    true = all_defined(Live, Regs0),             %Assertion.
+    Regs = def_regs([Dst], init_def_regs(Live)),
+    [I|defs(Is, Regs, update_regs(L, Regs0, D))];
+defs([{'try',_,{f,L}}=I|Is], Regs, D) ->
+    RegsAtLabel = init_def_regs(3),
+    [I|defs(Is, Regs, update_regs(L, RegsAtLabel, D))];
+defs([{try_case,_}=I|Is], _Regs, D) ->
+    [I|defs(Is, init_def_regs(3), D)];
+defs([{wait,_}=I|Is], _Regs, D) ->
+    [I|defs_unreachable(Is, D)];
+defs([{wait_timeout,_,_}=I|Is], _Regs, D) ->
+    [I|defs(Is, 0, D)];
+
+%% Exceptions.
+defs([{badmatch,_}=I|Is], _Regs, D) ->
+    [I|defs_unreachable(Is, D)];
+defs([{case_end,_}=I|Is], _Regs, D) ->
+    [I|defs_unreachable(Is, D)];
+defs([if_end=I|Is], _Regs, D) ->
+    [I|defs_unreachable(Is, D)];
+defs([{try_case_end,_}=I|Is], _Regs, D) ->
+    [I|defs_unreachable(Is, D)];
+
+%% Neutral instructions
+defs([{bs_context_to_binary,_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, D)];
+defs([{bs_restore2,_,_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, D)];
+defs([{bs_save2,_,_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, D)];
+defs([{deallocate,_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, D)];
+defs([{kill,_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, D)];
+defs([{line,_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, D)];
+defs([{recv_mark,_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, D)];
+defs([{recv_set,_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, D)];
+defs([timeout=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, D)];
+defs([{trim,_,_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, D)];
+defs([{try_end,_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, D)];
+defs([{'%',_}=I|Is], Regs, D) ->
+    [I|defs(Is, Regs, D)];
+defs([], _, _) -> [].
+
+defs_unreachable([{label,L}=I|Is], D) ->
+    case D of
+        #{L:=Regs} ->
+            [I|defs(Is, Regs, D)];
+        #{} ->
+            defs_unreachable(Is, D)
+    end;
+defs_unreachable([_|Is], D) ->
+    defs_unreachable(Is, D);
+defs_unreachable([], _D) -> [].
+
+defs_list(Is, Regs, D) ->
+    defs_list(Is, Regs, D, []).
+
+defs_list([{set,Ds,_,{alloc,Live,Info}}=I|Is], Regs0, D0, Acc) ->
+    true = all_defined(Live, Regs0),             %Assertion.
+    D = case Info of
+            {gc_bif,_,{f,Fail}} ->
+                update_regs(Fail, Regs0, D0);
+            {put_map,_,{f,Fail}} ->
+                update_regs(Fail, Regs0, D0);
+            _ ->
+                D0
+        end,
+    Regs = def_regs(Ds, init_def_regs(Live)),
+    defs_list(Is, Regs, D, [I|Acc]);
+defs_list([{set,Ds,_,Info}=I|Is], Regs0, D0, Acc) ->
+    D = case Info of
+            {bif,_,{f,Fail}} ->
+                update_regs(Fail, Regs0, D0);
+            {try_catch,'catch',{f,Fail}} ->
+                update_regs(Fail, init_def_regs(1), D0);
+            {try_catch,'try',{f,Fail}} ->
+                update_regs(Fail, init_def_regs(3), D0);
+            _ ->
+                D0
+        end,
+    Regs = def_regs(Ds, Regs0),
+    defs_list(Is, Regs, D, [I|Acc]);
+defs_list([], Regs, D, Acc) ->
+    {reverse(Acc),Regs,D}.
+
+init_def_regs(Arity) ->
+    (1 bsl Arity) - 1.
+
+def_regs([{x,X}|T], Regs) ->
+    def_regs(T, Regs bor (1 bsl X));
+def_regs([_|T], Regs) ->
+    def_regs(T, Regs);
+def_regs([], Regs) -> Regs.
+
+update_list([{f,L}|T], Regs, D0) ->
+    D = update_regs(L, Regs, D0),
+    update_list(T, Regs, D);
+update_list([_|T], Regs, D) ->
+    update_list(T, Regs, D);
+update_list([], _Regs, D) -> D.
+
+update_regs(L, Regs0, D) ->
+    case D of
+        #{L:=Regs1} ->
+            Regs = Regs0 band Regs1,
+            D#{L:=Regs};
+        #{} ->
+            D#{L=>Regs0}
+    end.
+
+all_defined(Live, Regs) ->
+    All = (1 bsl Live) - 1,
+    Regs band All =:= All.
diff --git a/lib/compiler/src/beam_validator.erl b/lib/compiler/src/beam_validator.erl
index be8908dd6b..2ad9747940 100644
--- a/lib/compiler/src/beam_validator.erl
+++ b/lib/compiler/src/beam_validator.erl
@@ -130,9 +130,8 @@ validate_0(Module, [{function,Name,Ar,Entry,Code}|Fs], Ft) ->
 	throw:Error ->
 	    %% Controlled error.
 	    [Error|validate_0(Module, Fs, Ft)];
-	Class:Error ->
+        Class:Error:Stack ->
 	    %% Crash.
-	    Stack = erlang:get_stacktrace(),
 	    io:fwrite("Function: ~w/~w\n", [Name,Ar]),
 	    erlang:raise(Class, Error, Stack)
     end.
@@ -294,6 +293,8 @@ valfun_1({bs_context_to_binary,Ctx}, #vst{current=#st{x=Xs}}=Vst) ->
     end;
 valfun_1(bs_init_writable=I, Vst) ->
     call(I, 1, Vst);
+valfun_1(build_stacktrace=I, Vst) ->
+    call(I, 1, Vst);
 valfun_1({move,{y,_}=Src,{y,_}=Dst}, Vst) ->
     %% The stack trimming optimization may generate a move from an initialized
     %% but unassigned Y register to another Y register.
diff --git a/lib/compiler/src/beam_z.erl b/lib/compiler/src/beam_z.erl
index 787e33c142..1c56b95a9e 100644
--- a/lib/compiler/src/beam_z.erl
+++ b/lib/compiler/src/beam_z.erl
@@ -38,8 +38,7 @@ function({function,Name,Arity,CLabel,Is0}) ->
 	Is = undo_renames(Is0),
 	{function,Name,Arity,CLabel,Is}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [Name,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
diff --git a/lib/compiler/src/cerl_clauses.erl b/lib/compiler/src/cerl_clauses.erl
index 7d6518c3c6..fa5104c01b 100644
--- a/lib/compiler/src/cerl_clauses.erl
+++ b/lib/compiler/src/cerl_clauses.erl
@@ -353,6 +353,8 @@ match(P, E, Bs) ->
 	map ->
 	    %% The most we can do is to say "definitely no match" if a
 	    %% map pattern is matched against non-map data.
+            %% (Note: See the document internal_doc/cerl-notes.md for
+            %% information why we don't try to do more here.)
 	    case E of
 		any ->
 		    {false, Bs};
diff --git a/lib/compiler/src/compile.erl b/lib/compiler/src/compile.erl
index 50b0ba76f8..770aa2c6c1 100644
--- a/lib/compiler/src/compile.erl
+++ b/lib/compiler/src/compile.erl
@@ -203,7 +203,12 @@ expand_opts(Opts0) ->
 	       {_,_,undefined} -> [debug_info|Opts0];
 	       {_,_,_} -> Opts0
 	   end,
-    foldr(fun expand_opt/2, [], Opts).
+    %% iff,unless processing is to complex...
+    Opts1 = case proplists:is_defined(makedep_side_effect,Opts) of
+                true -> proplists:delete(makedep,Opts);
+                false -> Opts
+            end,
+    foldr(fun expand_opt/2, [], Opts1).
 
 expand_opt(basic_validation, Os) ->
     [no_code_generation,to_pp,binary|Os];
@@ -674,6 +679,7 @@ select_list_passes_1([], _, Acc) ->
 standard_passes() ->
     [?pass(transform_module),
 
+     {iff,makedep_side_effect,?pass(makedep_and_output)},
      {iff,makedep,[
 	 ?pass(makedep),
 	 {unless,binary,?pass(makedep_output)}
@@ -706,14 +712,16 @@ core_passes() ->
       [{unless,no_copt,
        [{core_old_inliner,fun test_old_inliner/1,fun core_old_inliner/2},
 	{iff,doldinline,{listing,"oldinline"}},
-	{pass,sys_core_fold},
+	{unless,no_fold,{pass,sys_core_fold}},
 	{iff,dcorefold,{listing,"corefold"}},
 	{core_inline_module,fun test_core_inliner/1,fun core_inline_module/2},
 	{iff,dinline,{listing,"inline"}},
         {core_fold_after_inlining,fun test_any_inliner/1,
          fun core_fold_module_after_inlining/2},
+        {iff,dcopt,{listing,"copt"}},
+        {unless,no_alias,{pass,sys_core_alias}},
+        {iff,dalias,{listing,"core_alias"}},
 	?pass(core_transforms)]},
-       {iff,dcopt,{listing,"copt"}},
        {iff,'to_core',{done,"core"}}]}
      | kernel_passes()].
 
@@ -731,8 +739,6 @@ kernel_passes() ->
      ?pass(v3_kernel),
      {iff,dkern,{listing,"kernel"}},
      {iff,'to_kernel',{done,"kernel"}},
-     {pass,v3_life},
-     {iff,dlife,{listing,"life"}},
      {pass,v3_codegen},
      {iff,dcg,{listing,"codegen"}}
      | asm_passes()].
@@ -787,7 +793,7 @@ asm_passes() ->
      | binary_passes()].
 
 binary_passes() ->
-    [{iff,'to_dis',{listing,"dis"}},
+    [{iff,'to_dis',?pass(to_dis)},
      {native_compile,fun test_native/1,fun native_compile/2},
      {unless,binary,?pass(save_binary,not_werror)}
     ].
@@ -1128,6 +1134,16 @@ core_lint_module(Code, St) ->
 			      errors=St#compile.errors ++ Es}}
     end.
 
+%% makedep + output and continue
+makedep_and_output(Code0, St) ->
+    {ok,DepCode,St1} = makedep(Code0,St),
+    case makedep_output(DepCode, St1) of
+        {ok,_IgnoreCode,St2} ->
+            {ok,Code0,St2};
+        {error,St2} ->
+            {error,St2}
+    end.
+
 makedep(Code0, #compile{ifile=Ifile,ofile=Ofile,options=Opts}=St) ->
 
     %% Get the target of the Makefile rule.
@@ -1448,15 +1464,33 @@ save_core_code(Code, St) ->
 beam_asm(Code0, #compile{ifile=File,extra_chunks=ExtraChunks,options=CompilerOpts}=St) ->
     case debug_info(St) of
 	{ok,DebugInfo,Opts0} ->
-	    Source = paranoid_absname(File),
 	    Opts1 = [O || O <- Opts0, effects_code_generation(O)],
 	    Chunks = [{<<"Dbgi">>, DebugInfo} | ExtraChunks],
-	    {ok,Code} = beam_asm:module(Code0, Chunks, Source, Opts1, CompilerOpts),
+	    CompileInfo = compile_info(File, CompilerOpts, Opts1),
+	    {ok,Code} = beam_asm:module(Code0, Chunks, CompileInfo, CompilerOpts),
 	    {ok,Code,St#compile{abstract_code=[]}};
 	{error,Es} ->
 	    {error,St#compile{errors=St#compile.errors ++ [{File,Es}]}}
     end.
 
+compile_info(File, CompilerOpts, Opts) ->
+    IsSlim = member(slim, CompilerOpts),
+    IsDeterministic = member(deterministic, CompilerOpts),
+    Info0 = proplists:get_value(compile_info, Opts, []),
+    Info1 =
+	case paranoid_absname(File) of
+	    [_|_] = Source when not IsSlim, not IsDeterministic ->
+		[{source,Source} | Info0];
+	    _ ->
+		Info0
+	end,
+    Info2 =
+	case IsDeterministic of
+	    false -> [{options,proplists:delete(compile_info, Opts)} | Info1];
+	    true -> Info1
+	end,
+    Info2.
+
 paranoid_absname(""=File) ->
     File;
 paranoid_absname(File) ->
@@ -1512,15 +1546,14 @@ native_compile_1(Code, St) ->
 		    {error,St#compile{errors=St#compile.errors ++ Es}}
 	    end
     catch
-	Class:R ->
-	    Stk = erlang:get_stacktrace(),
+	Class:R:Stack ->
 	    case IgnoreErrors of
 		true ->
 		    Ws = [{St#compile.ifile,
-			   [{none,?MODULE,{native_crash,R,Stk}}]}],
+			   [{none,?MODULE,{native_crash,R,Stack}}]}],
 		    {ok,St#compile{warnings=St#compile.warnings ++ Ws}};
 		false ->
-		    erlang:raise(Class, R, Stk)
+		    erlang:raise(Class, R, Stack)
 	    end
     end.
 
@@ -1748,6 +1781,21 @@ listing(LFun, Ext, Code, St) ->
 	    {error,St#compile{errors=St#compile.errors ++ Es}}
     end.
 
+to_dis(Code, #compile{module=Module,ofile=Outfile}=St) ->
+    Loaded = code:is_loaded(Module),
+    Sticky = code:is_sticky(Module),
+    _ = [code:unstick_mod(Module) || Sticky],
+
+    {module,Module} = code:load_binary(Module, "", Code),
+    DestDir = filename:dirname(Outfile),
+    DisFile = filename:join(DestDir, atom_to_list(Module) ++ ".dis"),
+    ok = erts_debug:dis_to_file(Module, DisFile),
+
+    %% Restore loaded module
+    _ = [{module, Module} = code:load_file(Module) || Loaded =/= false],
+    [code:stick_mod(Module) || Sticky],
+    {ok,Code,St}.
+
 output_encoding(F, #compile{encoding = none}) ->
     ok = io:setopts(F, [{encoding, epp:default_encoding()}]);
 output_encoding(F, #compile{encoding = Encoding}) ->
@@ -1923,12 +1971,12 @@ pre_load() ->
 	 erl_lint,
 	 erl_parse,
 	 erl_scan,
+	 sys_core_alias,
 	 sys_core_bsm,
 	 sys_core_dsetel,
 	 sys_core_fold,
 	 v3_codegen,
 	 v3_core,
-	 v3_kernel,
-	 v3_life],
+	 v3_kernel],
     _ = code:ensure_modules_loaded(L),
     ok.
diff --git a/lib/compiler/src/compiler.app.src b/lib/compiler/src/compiler.app.src
index 3139d68902..cf32fd251c 100644
--- a/lib/compiler/src/compiler.app.src
+++ b/lib/compiler/src/compiler.app.src
@@ -58,6 +58,7 @@
 	     core_lib,
 	     erl_bifs,
 	     rec_env,
+	     sys_core_alias,
 	     sys_core_bsm,
 	     sys_core_dsetel,
 	     sys_core_fold,
@@ -67,8 +68,7 @@
 	     v3_codegen,
 	     v3_core,
 	     v3_kernel,
-	     v3_kernel_pp,
-	     v3_life
+	     v3_kernel_pp
 	    ]},
   {registered, []},
   {applications, [kernel, stdlib]},
diff --git a/lib/compiler/src/core_lint.erl b/lib/compiler/src/core_lint.erl
index 7d3513c0ba..6e2114be56 100644
--- a/lib/compiler/src/core_lint.erl
+++ b/lib/compiler/src/core_lint.erl
@@ -353,12 +353,6 @@ expr(#c_case{arg=Arg,clauses=Cs}, Def, Rt, St0) ->
     Pc = case_patcount(Cs),
     St1 = body(Arg, Def, Pc, St0),
     clauses(Cs, Def, Pc, Rt, St1);
-expr(#c_receive{clauses=Cs,timeout=#c_literal{val=infinity},
-		action=#c_literal{}},
-     Def, Rt, St) ->
-    %% If the timeout is 'infinity', the after code can never
-    %% be reached. We don't care if the return count is wrong.
-    clauses(Cs, Def, 1, Rt, St);
 expr(#c_receive{clauses=Cs,timeout=T,action=A}, Def, Rt, St0) ->
     St1 = expr(T, Def, 1, St0),
     St2 = body(A, Def, Rt, St1),
diff --git a/lib/compiler/src/core_pp.erl b/lib/compiler/src/core_pp.erl
index cff6c7098b..2516a9a1e1 100644
--- a/lib/compiler/src/core_pp.erl
+++ b/lib/compiler/src/core_pp.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1999-2016. All Rights Reserved.
+%% Copyright Ericsson AB 1999-2017. All Rights Reserved.
 %% 
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -464,7 +464,7 @@ indent(#ctxt{indent=N}) ->
 	N =< 0 ->
 	    "";
 	true ->
-	    string:chars($\t, N div ?TAB_WIDTH, spaces(N rem ?TAB_WIDTH))
+           lists:duplicate(N div ?TAB_WIDTH, $\t) ++ spaces(N rem ?TAB_WIDTH)
     end.
 
 nl_indent(Ctxt) -> [$\n|indent(Ctxt)].
diff --git a/lib/compiler/src/core_scan.erl b/lib/compiler/src/core_scan.erl
index 9f0676538f..a50a2ffa8d 100644
--- a/lib/compiler/src/core_scan.erl
+++ b/lib/compiler/src/core_scan.erl
@@ -200,8 +200,8 @@ pre_string(eof, Q, _, Sp, SoFar, Pos) ->
     pre_string_error(Q, Sp, SoFar, Pos).
 
 pre_string_error(Q, Sp, SoFar, Pos) ->
-    S = reverse(string:substr(SoFar, 1, string:chr(SoFar, Q)-1)),
-    pre_error({string,Q,string:substr(S, 1, 16)}, Sp, Pos).
+    [S,_] = string:split(SoFar, [Q]),
+    pre_error({string,Q,string:slice(string:reverse(S), 0, 16)}, Sp, Pos).
 
 pre_char([C|Cs], SoFar) -> pre_char(C, Cs, SoFar);
 pre_char([], _) -> more;
diff --git a/lib/compiler/src/genop.tab b/lib/compiler/src/genop.tab
index b5688de339..397e478e1e 100755
--- a/lib/compiler/src/genop.tab
+++ b/lib/compiler/src/genop.tab
@@ -545,3 +545,12 @@ BEAM_FORMAT_NUMBER=0
 ##      Test the arity of Reg and jumps to Lbl if it is not N.
 ##      Test the first element of the tuple and jumps to Lbl if it is not Atom.
 159: is_tagged_tuple/4
+
+# OTP 21
+
+## @spec build_stacktrace
+## @doc  Given the raw stacktrace in x(0), build a cooked stacktrace suitable
+##       for human consumption. Store it in x(0). Destroys all other registers.
+##       Do a garbage collection if necessary to allocate space on the heap
+##       for the result.
+160: build_stacktrace/0
diff --git a/lib/compiler/src/sys_core_alias.erl b/lib/compiler/src/sys_core_alias.erl
new file mode 100644
index 0000000000..1bce1577d1
--- /dev/null
+++ b/lib/compiler/src/sys_core_alias.erl
@@ -0,0 +1,307 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 1999-2016. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+%% Purpose : Replace values by aliases from patterns optimisation for Core
+
+%% Replace expressions by aliases from patterns. For example:
+%%
+%%    example({ok, Val}) ->
+%%        {ok, Val}.
+%%
+%% will become:
+%%
+%%    example({ok, Val} = Tuple) ->
+%%        Tuple.
+%%
+%% Currently this pass aliases tuple and cons nodes made of literals,
+%% variables and other cons. The tuple/cons may appear anywhere in the
+%% pattern and it will be aliased if used later on.
+%%
+%% Notice a tuple/cons made only of literals is not aliased as it may
+%% be part of the literal pool.
+
+-module(sys_core_alias).
+
+-export([module/2]).
+
+-include("core_parse.hrl").
+
+-define(NOTSET, 0).
+
+-record(sub, {p=#{} :: #{term() => ?NOTSET | atom()},              %% Found pattern substitutions
+              v=cerl_sets:new() :: cerl_sets:set(cerl:var_name()), %% Variables used by patterns
+              t=undefined :: term()}).                             %% Temporary information from pre to post
+
+-type sub() :: #sub{}.
+
+-spec module(cerl:c_module(), [compile:option()]) ->
+        {'ok',cerl:c_module(),[]}.
+
+module(#c_module{defs=Ds0}=Mod, _Opts) ->
+    Ds1 = [def(D) || D <- Ds0],
+    {ok,Mod#c_module{defs=Ds1},[]}.
+
+def({#c_var{name={F,Arity}}=Name,B0}) ->
+    try
+        put(new_var_num, 0),
+        {B1,_} = cerl_trees:mapfold(fun pre/2, fun post/2, sub_new(undefined), B0),
+        erase(new_var_num),
+        {Name,B1}
+    catch
+        Class:Error:Stack ->
+            io:fwrite("Function: ~w/~w\n", [F,Arity]),
+            erlang:raise(Class, Error, Stack)
+    end.
+
+pre(#c_let{vars=Vars}=Node, Sub) ->
+    {Node,sub_fold(get_variables(Vars), Sub)};
+
+pre(#c_fun{vars=Vars}=Node, Sub) ->
+    {Node,sub_fold(get_variables(Vars), Sub)};
+
+pre(#c_clause{pats=Pats}=Node, Sub0) ->
+    VarNames = get_variables(Pats),
+    Sub1 = sub_fold(VarNames, Sub0),
+    Keys = get_pattern_keys(Pats),
+    Sub2 = sub_add_keys(Keys, Sub1),
+
+    #sub{v=SubNames,t=Temp} = Sub2,
+    Sub3 = Sub2#sub{v=merge_variables(VarNames, SubNames),
+                    t={clause,Pats,Keys,SubNames,Temp}},
+
+    {Node#c_clause{pats=[]},Sub3};
+
+pre(Node, Sub0) ->
+    %% We cache only tuples and cons.
+    case cerl:is_data(Node) andalso not cerl:is_literal(Node) of
+        false ->
+            {Node,Sub0};
+        true ->
+            Kind = cerl:data_type(Node),
+            Es = cerl:data_es(Node),
+            case sub_cache_nodes(Kind, Es, Sub0) of
+                {Name,Sub1} ->
+                    {cerl:ann_c_var(cerl:get_ann(Node), Name),Sub1};
+                error ->
+                    {Node,Sub0}
+            end
+    end.
+
+post(#c_let{}=Node, Sub) ->
+    {Node,sub_unfold(Sub)};
+
+post(#c_fun{}=Node, Sub) ->
+    {Node,sub_unfold(Sub)};
+
+post(#c_clause{}=Node, #sub{t={clause,Pats0,Keys,V,T}}=Sub0) ->
+    {Sub1,PostKeys} = sub_take_keys(Keys, Sub0),
+    Pats1 = put_pattern_keys(Pats0, PostKeys),
+    Sub2 = sub_unfold(Sub1#sub{v=V,t=T}),
+    {Node#c_clause{pats=Pats1},Sub2};
+
+post(Node, Sub) ->
+    {Node,Sub}.
+
+%% sub_new/1
+%% sub_add_keys/2
+%% sub_take_keys/3
+%% sub_cache_nodes/3
+%%
+%% Manages the substitutions record.
+
+%% Builds a new sub.
+-spec sub_new(term()) -> sub().
+sub_new(Temp) ->
+    #sub{t=Temp}.
+
+%% Folds the sub into a new one if the variables in nodes are not disjoint
+sub_fold(VarNames, #sub{v=SubNames}=Sub) ->
+    case is_disjoint_variables(VarNames, SubNames) of
+        true  -> Sub#sub{t={temp,Sub#sub.t}};
+        false -> sub_new({sub,Sub})
+    end.
+
+%% Unfolds the sub in case one was folded in the previous step
+sub_unfold(#sub{t={temp,Temp}}=Sub) ->
+    Sub#sub{t=Temp};
+sub_unfold(#sub{t={sub,Sub}}) ->
+    Sub.
+
+%% Adds the keys extracted from patterns to the state.
+-spec sub_add_keys([term()], sub()) -> sub().
+sub_add_keys(Keys, #sub{p=Pat0}=Sub) ->
+    Pat1 =
+        lists:foldl(fun(Key, Acc) ->
+            false = maps:is_key(Key, Acc),         %Assertion.
+            maps:put(Key, ?NOTSET, Acc)
+        end, Pat0, Keys),
+    Sub#sub{p=Pat1}.
+
+%% Take the keys from the map taking into account the keys
+%% that have changed as those must become aliases in the pattern.
+-spec sub_take_keys([term()], sub()) -> {sub(), [{term(), atom()}]}.
+sub_take_keys(Keys, #sub{p=Pat0}=Sub) ->
+    {Pat1,Acc} = sub_take_keys(Keys, Pat0, []),
+    {Sub#sub{p=Pat1},Acc}.
+
+sub_take_keys([K|T], Sub0, Acc) ->
+    case maps:take(K, Sub0) of
+        {?NOTSET,Sub1} ->
+            sub_take_keys(T, Sub1, Acc);
+        {Name,Sub1} ->
+            sub_take_keys(T, Sub1, [{K,Name}|Acc])
+    end;
+sub_take_keys([], Sub, Acc) ->
+    {Sub,Acc}.
+
+%% Check if the node can be cached based on the state information.
+%% If it can be cached and it does not have an alias for it, we
+%% build one.
+-spec sub_cache_nodes(atom(), [cerl:cerl()], sub()) -> {atom(), sub()} | error.
+sub_cache_nodes(Kind, Nodes, #sub{p=Pat}=Sub) ->
+    case nodes_to_key(Kind, Nodes) of
+        {ok, Key} ->
+            case Pat of
+                #{Key := ?NOTSET} ->
+                    new_var_name(Key, Sub);
+                #{Key := Name} ->
+                    {Name,Sub};
+                #{} ->
+                    error
+            end;
+        error ->
+            error
+    end.
+
+new_var_name(Key, #sub{p=Pat}=Sub) ->
+    Counter = get(new_var_num),
+    Name = list_to_atom("@r" ++ integer_to_list(Counter)),
+    put(new_var_num, Counter + 1),
+    {Name,Sub#sub{p=maps:put(Key, Name, Pat)}}.
+
+%% get_variables/1
+%% is_disjoint_variables/2
+%% merge_variables/2
+
+get_variables(NodesList) ->
+    cerl_sets:from_list([Var || Node <- NodesList, Var <- cerl_trees:variables(Node)]).
+
+is_disjoint_variables(Vars1, Vars2) ->
+    cerl_sets:is_disjoint(Vars1, Vars2).
+
+merge_variables(Vars1, Vars2) ->
+    cerl_sets:union(Vars1, Vars2).
+
+%% get_pattern_keys/2
+%% put_pattern_keys/2
+%%
+%% Gets keys from patterns or add them as aliases.
+
+get_pattern_keys(Patterns) ->
+    lists:foldl(fun get_pattern_keys/2, [], Patterns).
+
+get_pattern_keys(#c_tuple{es=Es}, Acc0) ->
+    Acc1 = accumulate_pattern_keys(tuple, Es, Acc0),
+    lists:foldl(fun get_pattern_keys/2, Acc1, Es);
+get_pattern_keys(#c_cons{hd=Hd,tl=Tl}, Acc0) ->
+    Acc1 = accumulate_pattern_keys(cons, [Hd, Tl], Acc0),
+    get_pattern_keys(Tl, get_pattern_keys(Hd, Acc1));
+get_pattern_keys(#c_alias{pat=Pat}, Acc0) ->
+    get_pattern_keys(Pat, Acc0);
+get_pattern_keys(#c_map{es=Es}, Acc0) ->
+    lists:foldl(fun get_pattern_keys/2, Acc0, Es);
+get_pattern_keys(#c_map_pair{val=Val}, Acc0) ->
+    get_pattern_keys(Val, Acc0);
+get_pattern_keys(_, Acc) ->
+    Acc.
+
+accumulate_pattern_keys(Kind, Nodes, Acc) ->
+    case nodes_to_key(Kind, Nodes) of
+        {ok,Key} -> [Key|Acc];
+        error -> Acc
+    end.
+
+put_pattern_keys(Patterns, []) ->
+    Patterns;
+put_pattern_keys(Patterns, Keys) ->
+    {NewPatterns,Map} =
+        lists:mapfoldl(fun alias_pattern_keys/2, maps:from_list(Keys), Patterns),
+    %% Check all aliases have been consumed from the map.
+    0 = map_size(Map),
+    NewPatterns.
+
+alias_pattern_keys(#c_tuple{anno=Anno,es=Es0}=Node, Acc0) ->
+    {Es1,Acc1} = lists:mapfoldl(fun alias_pattern_keys/2, Acc0, Es0),
+    nodes_to_alias(tuple, Es0, Anno, Node#c_tuple{es=Es1}, Acc1);
+alias_pattern_keys(#c_cons{anno=Anno,hd=Hd0,tl=Tl0}=Node, Acc0) ->
+    {Hd1,Acc1} = alias_pattern_keys(Hd0, Acc0),
+    {Tl1,Acc2} = alias_pattern_keys(Tl0, Acc1),
+    nodes_to_alias(cons, [Hd0, Tl0], Anno, Node#c_cons{hd=Hd1,tl=Tl1}, Acc2);
+alias_pattern_keys(#c_alias{pat=Pat0}=Node, Acc0) ->
+    {Pat1,Acc1} = alias_pattern_keys(Pat0, Acc0),
+    {Node#c_alias{pat=Pat1}, Acc1};
+alias_pattern_keys(#c_map{es=Es0}=Node, Acc0) ->
+    {Es1,Acc1} = lists:mapfoldl(fun alias_pattern_keys/2, Acc0, Es0),
+    {Node#c_map{es=Es1}, Acc1};
+alias_pattern_keys(#c_map_pair{val=Val0}=Node, Acc0) ->
+    {Val1,Acc1} = alias_pattern_keys(Val0, Acc0),
+    {Node#c_map_pair{val=Val1}, Acc1};
+alias_pattern_keys(Pattern, Acc) ->
+    {Pattern,Acc}.
+
+%% Check if a node must become an alias because
+%% its pattern was used later on as an expression.
+nodes_to_alias(Kind, Inner, Anno, Node, Keys0) ->
+    case nodes_to_key(Kind, Inner) of
+        {ok,Key} ->
+            case maps:take(Key, Keys0) of
+                {Name,Keys1} ->
+                    Var = cerl:ann_c_var(Anno, Name),
+                    {cerl:ann_c_alias(Anno, Var, Node), Keys1};
+                error ->
+                    {Node,Keys0}
+            end;
+        error ->
+            {Node,Keys0}
+     end.
+
+%% Builds the key used to check if a value can be
+%% replaced by an alias. It considers literals,
+%% aliases, variables, tuples and cons recursively.
+nodes_to_key(Kind, Nodes) ->
+    nodes_to_key(Nodes, [], Kind).
+
+nodes_to_key([#c_alias{var=Var}|T], Acc, Kind) ->
+    nodes_to_key([Var|T], Acc, Kind);
+nodes_to_key([#c_var{name=Name}|T], Acc, Kind) ->
+    nodes_to_key(T, [[var,Name]|Acc], Kind);
+nodes_to_key([Node|T], Acc0, Kind) ->
+    case cerl:is_data(Node) of
+        false ->
+            error;
+        true ->
+            case nodes_to_key(cerl:data_es(Node), [], cerl:data_type(Node)) of
+                {ok,Key} ->
+                    nodes_to_key(T, [Key|Acc0], Kind);
+                error ->
+                    error
+            end
+    end;
+nodes_to_key([], Acc, Kind) ->
+    {ok,[Kind|Acc]}.
diff --git a/lib/compiler/src/sys_core_bsm.erl b/lib/compiler/src/sys_core_bsm.erl
index 3e04cc33df..37e071fafa 100644
--- a/lib/compiler/src/sys_core_bsm.erl
+++ b/lib/compiler/src/sys_core_bsm.erl
@@ -44,8 +44,7 @@ function([{#c_var{name={F,Arity}}=Name,B0}|Fs], FsAcc, Ws0) ->
         {B,Ws} ->
             function(Fs, [{Name,B}|FsAcc], Ws)
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [F,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end;
diff --git a/lib/compiler/src/sys_core_dsetel.erl b/lib/compiler/src/sys_core_dsetel.erl
index bd3eeae238..9e2df69b33 100644
--- a/lib/compiler/src/sys_core_dsetel.erl
+++ b/lib/compiler/src/sys_core_dsetel.erl
@@ -81,8 +81,7 @@ visit_module_1([{Name,F0}|Fs], Env, Acc) ->
 	{F,_} ->
 	    visit_module_1(Fs, Env, [{Name,F}|Acc])
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    #c_var{name={Func,Arity}} = Name,
 	    io:fwrite("Function: ~w/~w\n", [Func,Arity]),
 	    erlang:raise(Class, Error, Stack)
diff --git a/lib/compiler/src/sys_core_fold.erl b/lib/compiler/src/sys_core_fold.erl
index d73060fb7e..e28d48acf5 100644
--- a/lib/compiler/src/sys_core_fold.erl
+++ b/lib/compiler/src/sys_core_fold.erl
@@ -125,8 +125,7 @@ function_1({#c_var{name={F,Arity}}=Name,B0}) ->
 			  end, B0, 20),
 	{Name,B}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [F,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
@@ -415,9 +414,20 @@ expr(#c_call{module=M0,name=N0}=Call0, Ctxt, Sub) ->
 	no -> call(Call, M1, N1, Sub);
 	{yes,Seq} -> expr(Seq, Ctxt, Sub)
     end;
+expr(#c_primop{name=#c_literal{val=build_stacktrace}}, effect, _Sub) ->
+    void();
 expr(#c_primop{args=As0}=Prim, _, Sub) ->
     As1 = expr_list(As0, value, Sub),
     Prim#c_primop{args=As1};
+expr(#c_catch{anno=Anno,body=B}, effect, Sub) ->
+    %% When the return value of the 'catch' is ignored, we can replace it
+    %% with a try/catch to avoid building a stack trace when an exception
+    %% occurs.
+    Var = #c_var{name='catch_value'},
+    Evs = [#c_var{name='Class'},#c_var{name='Reason'},#c_var{name='Stk'}],
+    Try = #c_try{anno=Anno,arg=B,vars=[Var],body=Var,
+                 evars=Evs,handler=void()},
+    expr(Try, effect, Sub);
 expr(#c_catch{body=B0}=Catch, _, Sub) ->
     %% We can remove catch if the value is simple
     B1 = body(B0, value, Sub),
@@ -2422,16 +2432,10 @@ move_let_into_expr(#c_let{vars=InnerVs0,body=InnerBody0}=Inner,
     Outer#c_let{vars=OuterVs,arg=Arg,
 		body=Inner#c_let{vars=InnerVs,arg=OuterBody,body=InnerBody}};
 move_let_into_expr(#c_let{vars=Lvs0,body=Lbody0}=Let,
-		   #c_case{arg=Cexpr0,clauses=[Ca0,Cb0|Cs]}=Case, Sub0) ->
-    %% Test if there are no more clauses than Ca0 and Cb0, or if
-    %% Cb0 is guaranteed to match.
-    TwoClauses = Cs =:= [] orelse
-	case Cb0 of
-	    #c_clause{pats=[#c_var{}],guard=#c_literal{val=true}} -> true;
-	    _ -> false
-	end,
-    case {TwoClauses,is_failing_clause(Ca0),is_failing_clause(Cb0)} of
-	{true,false,true} ->
+		   #c_case{arg=Cexpr0,clauses=[Ca0|Cs0]}=Case, Sub0) ->
+    case not is_failing_clause(Ca0) andalso
+        are_all_failing_clauses(Cs0) of
+	true ->
 	    %% let <Lvars> = case <Case-expr> of
 	    %%                  <Cpats> -> <Clause-body>;
 	    %%                  <OtherCpats> -> erlang:error(...)
@@ -2467,8 +2471,8 @@ move_let_into_expr(#c_let{vars=Lvs0,body=Lbody0}=Let,
 				  body=Lbody},
 
 		    Ca = Ca0#c_clause{pats=CaPats,guard=G,body=B},
-		    Cb = clause(Cb0, Cexpr, value, Sub0),
-		    Case#c_case{arg=Cexpr,clauses=[Ca,Cb]}
+		    Cs = [clause(C, Cexpr, value, Sub0) || C <- Cs0],
+		    Case#c_case{arg=Cexpr,clauses=[Ca|Cs]}
 	    catch
 		nomatch ->
 		    %% This is not a defeat. The code will eventually
@@ -2476,7 +2480,7 @@ move_let_into_expr(#c_let{vars=Lvs0,body=Lbody0}=Let,
 		    %% optimizations done in this module.
 		    impossible
 	    end;
-	{_,_,_} -> impossible
+	false -> impossible
     end;
 move_let_into_expr(#c_let{vars=Lvs0,body=Lbody0}=Let,
 		   #c_seq{arg=Sarg0,body=Sbody0}=Seq, Sub0) ->
@@ -2499,6 +2503,9 @@ move_let_into_expr(#c_let{vars=Lvs0,body=Lbody0}=Let,
 				      body=Lbody}};
 move_let_into_expr(_Let, _Expr, _Sub) -> impossible.
 
+are_all_failing_clauses(Cs) ->
+    all(fun is_failing_clause/1, Cs).
+
 is_failing_clause(#c_clause{body=B}) ->
     will_fail(B).
 
@@ -2616,9 +2623,13 @@ delay_build_expr_1(#c_receive{clauses=Cs0,
 			      timeout=Timeout,
 			      action=A0}=Rec, TypeSig) ->
     Cs = delay_build_cs(Cs0, TypeSig),
-    A = case Timeout of
-	    #c_literal{val=infinity} -> A0;
-	    _ -> delay_build_expr(A0, TypeSig)
+    A = case {Timeout,A0} of
+	    {#c_literal{val=infinity},#c_literal{}} ->
+                {_Type,Arity} = TypeSig,
+                Es = lists:duplicate(Arity, A0),
+                core_lib:make_values(Es);
+	    _ ->
+                delay_build_expr(A0, TypeSig)
 	end,
     Rec#c_receive{clauses=Cs,action=A};
 delay_build_expr_1(#c_seq{body=B0}=Seq, TypeSig) ->
diff --git a/lib/compiler/src/v3_codegen.erl b/lib/compiler/src/v3_codegen.erl
index 47c1567f10..62c6c54b9f 100644
--- a/lib/compiler/src/v3_codegen.erl
+++ b/lib/compiler/src/v3_codegen.erl
@@ -19,25 +19,6 @@
 %%
 %% Purpose : Code generator for Beam.
 
-%% The following assumptions have been made:
-%%
-%% 1. Matches, i.e. things with {match,M,Ret} wrappers, only return
-%% values; no variables are exported. If the match would have returned
-%% extra variables then these have been transformed to multiple return
-%% values.
-%% 
-%% 2. All BIF's called in guards are gc-safe so there is no need to
-%% put thing on the stack in the guard.  While this would in principle
-%% work it would be difficult to keep track of the stack depth when
-%% trimming.
-%%
-%% The code generation uses variable lifetime information added by
-%% the v3_life module to save variables, allocate registers and 
-%% move registers to the stack when necessary.
-%%
-%% We try to use a consistent variable name scheme throughout.  The
-%% StackReg record is always called Bef,Int<n>,Aft.
-
 -module(v3_codegen).
 
 %% The main interface.
@@ -45,12 +26,14 @@
 
 -import(lists, [member/2,keymember/3,keysort/2,keydelete/3,
 		append/1,flatmap/2,filter/2,foldl/3,foldr/3,mapfoldl/3,
-		sort/1,reverse/1,reverse/2]).
--import(v3_life, [vdb_find/2]).
+		sort/1,reverse/1,reverse/2,map/2]).
+-import(ordsets, [add_element/2,intersection/2,union/2]).
 
-%%-compile([export_all]).
+-include("v3_kernel.hrl").
 
--include("v3_life.hrl").
+%% These are not defined in v3_kernel.hrl.
+get_kanno(Kthing) -> element(2, Kthing).
+set_kanno(Kthing, Anno) -> setelement(2, Kthing, Anno).
 
 %% Main codegen structure.
 -record(cg, {lcount=1,				%Label counter
@@ -61,38 +44,376 @@
 	     functable=#{},	                %Map of local functions: {Name,Arity}=>Label
 	     in_catch=false,			%Inside a catch or not.
 	     need_frame,			%Need a stack frame.
-	     ultimate_failure			%Label for ultimate match failure.
-	    }).			
+	     ultimate_failure,			%Label for ultimate match failure.
+             ctx                                %Match context.
+	    }).
 
 %% Stack/register state record.
 -record(sr, {reg=[],				%Register table
 	     stk=[],				%Stack table
-	     res=[]}).				%Reserved regs: [{reserved,I,V}]
+	     res=[]}).				%Registers to reserve
+
+%% Internal records.
+-record(cg_need_heap, {anno=[] :: term(),
+                       h=0 :: integer()}).
+-record(cg_block, {anno=[] :: term(),
+                   es=[] :: [term()]}).
+
+-type vdb_entry() :: {atom(),non_neg_integer(),non_neg_integer()}.
 
--type life_module() :: {module(),_,_,[_]}.
+-record(l, {i=0 :: non_neg_integer(),           %Op number
+	    vdb=[] :: [vdb_entry()],            %Variable database
+	    a=[] :: [term()]}).                 %Core annotation
 
--spec module(life_module(), [compile:option()]) -> {'ok',beam_asm:module_code()}.
+-spec module(#k_mdef{}, [compile:option()]) -> {'ok',beam_asm:module_code()}.
 
-module({Mod,Exp,Attr,Forms}, _Options) ->
-    {Fs,St} = functions(Forms, {atom,Mod}),
-    {ok,{Mod,Exp,Attr,Fs,St#cg.lcount}}.
+module(#k_mdef{name=Mod,exports=Es,attributes=Attr,body=Forms}, _Opts) ->
+    {Asm,St} = functions(Forms, {atom,Mod}),
+    {ok,{Mod,Es,Attr,Asm,St#cg.lcount}}.
 
 functions(Forms, AtomMod) ->
     mapfoldl(fun (F, St) -> function(F, AtomMod, St) end, #cg{lcount=1}, Forms).
 
-function({function,Name,Arity,Asm0,Vb,Vdb,Anno}, AtomMod, St0) ->
+function(#k_fdef{anno=#k{a=Anno},func=Name,arity=Arity,
+                 vars=As,body=Kb}, AtomMod, St0) ->
     try
-	{Asm,EntryLabel,St} = cg_fun(Vb, Asm0, Vdb, AtomMod,
-				     {Name,Arity}, Anno, St0),
-	Func = {function,Name,Arity,EntryLabel,Asm},
-	{Func,St}
+        #k_match{} = Kb,                   %Assertion.
+
+        %% Try to suppress the stack frame unless it is
+        %% really needed.
+        Body0 = avoid_stack_frame(Kb),
+
+        %% Annotate kernel records with variable usage.
+        Vdb0 = init_vars(As),
+        {Body,_,Vdb} = body(Body0, 1, Vdb0),
+
+        %% Generate the BEAM assembly code.
+        {Asm,EntryLabel,St} = cg_fun(Body, As, Vdb, AtomMod,
+                                     {Name,Arity}, Anno, St0),
+        Func = {function,Name,Arity,EntryLabel,Asm},
+        {Func,St}
+    catch
+        Class:Error:Stack ->
+            io:fwrite("Function: ~w/~w\n", [Name,Arity]),
+            erlang:raise(Class, Error, Stack)
+    end.
+
+
+%% avoid_stack_frame(Kernel) -> Kernel'
+%%  If possible, avoid setting up a stack frame. Functions
+%%  that only do matching, calls to guard BIFs, and tail-recursive
+%%  calls don't need a stack frame.
+
+avoid_stack_frame(#k_match{body=Body}=M) ->
+    try
+        M#k_match{body=avoid_stack_frame_1(Body)}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
-	    io:fwrite("Function: ~w/~w\n", [Name,Arity]),
-	    erlang:raise(Class, Error, Stack)
+        impossible ->
+            M
     end.
 
+avoid_stack_frame_1(#k_alt{first=First0,then=Then0}=Alt) ->
+    First = avoid_stack_frame_1(First0),
+    Then = avoid_stack_frame_1(Then0),
+    Alt#k_alt{first=First,then=Then};
+avoid_stack_frame_1(#k_bif{op=Op}=Bif) ->
+    case Op of
+        #k_internal{} ->
+            %% Most internal BIFs clobber the X registers.
+            throw(impossible);
+        _ ->
+            Bif
+    end;
+avoid_stack_frame_1(#k_break{anno=Anno,args=Args}) ->
+    #k_guard_break{anno=Anno,args=Args};
+avoid_stack_frame_1(#k_guard_break{}=Break) ->
+    Break;
+avoid_stack_frame_1(#k_enter{}=Enter) ->
+    %% Tail-recursive calls don't need a stack frame.
+    Enter;
+avoid_stack_frame_1(#k_guard{clauses=Cs0}=Guard) ->
+    Cs = avoid_stack_frame_list(Cs0),
+    Guard#k_guard{clauses=Cs};
+avoid_stack_frame_1(#k_guard_clause{guard=G0,body=B0}=C) ->
+    G = avoid_stack_frame_1(G0),
+    B = avoid_stack_frame_1(B0),
+    C#k_guard_clause{guard=G,body=B};
+avoid_stack_frame_1(#k_match{anno=A,vars=Vs,body=B0,ret=Ret}) ->
+    %% Use #k_guard_match{} instead to avoid saving the X registers
+    %% to the stack before matching.
+    B = avoid_stack_frame_1(B0),
+    #k_guard_match{anno=A,vars=Vs,body=B,ret=Ret};
+avoid_stack_frame_1(#k_guard_match{body=B0}=M) ->
+    B = avoid_stack_frame_1(B0),
+    M#k_guard_match{body=B};
+avoid_stack_frame_1(#k_protected{arg=Arg0}=Prot) ->
+    Arg = avoid_stack_frame_1(Arg0),
+    Prot#k_protected{arg=Arg};
+avoid_stack_frame_1(#k_put{}=Put) ->
+    Put;
+avoid_stack_frame_1(#k_return{}=Ret) ->
+    Ret;
+avoid_stack_frame_1(#k_select{var=#k_var{anno=Vanno},types=Types0}=Select) ->
+    case member(reuse_for_context, Vanno) of
+        false ->
+            Types = avoid_stack_frame_list(Types0),
+            Select#k_select{types=Types};
+        true ->
+            %% Including binary patterns that overwrite the register containing
+            %% the binary with the match context may not be safe. For example,
+            %% bs_match_SUITE:bin_tail_e/1 with inlining will be rejected by
+            %% beam_validator.
+            %%
+            %% Essentially the following code is produced:
+            %%
+            %% bs_match {x,0} => {x,0}
+            %% ...
+            %% bs_match {x,0} => {x,1}  %% ILLEGAL
+            %%
+            %% A bs_match instruction will only accept a match context as the
+            %% source operand if the source and destination registers are the
+            %% the same (as in the first bs_match instruction above).
+            %% The second bs_match instruction is therefore illegal.
+            %%
+            %% This situation is avoided if there is a stack frame:
+            %%
+            %% move {x,0} => {y,0}
+            %% bs_match {x,0} => {x,0}
+            %% ...
+            %% bs_match {y,0} => {x,1}  %% LEGAL
+            %%
+            throw(impossible)
+    end;
+avoid_stack_frame_1(#k_seq{arg=A0,body=B0}=Seq) ->
+    A = avoid_stack_frame_1(A0),
+    B = avoid_stack_frame_1(B0),
+    Seq#k_seq{arg=A,body=B};
+avoid_stack_frame_1(#k_test{}=Test) ->
+    Test;
+avoid_stack_frame_1(#k_type_clause{values=Values0}=TC) ->
+    Values = avoid_stack_frame_list(Values0),
+    TC#k_type_clause{values=Values};
+avoid_stack_frame_1(#k_val_clause{body=B0}=VC) ->
+    B = avoid_stack_frame_1(B0),
+    VC#k_val_clause{body=B};
+avoid_stack_frame_1(_Body) ->
+    throw(impossible).
+
+avoid_stack_frame_list([H|T]) ->
+    [avoid_stack_frame_1(H)|avoid_stack_frame_list(T)];
+avoid_stack_frame_list([]) -> [].
+
+
+%% This pass creates beam format annotated with variable lifetime
+%% information.  Each thing is given an index and for each variable we
+%% store the first and last index for its occurrence.  The variable
+%% database, VDB, attached to each thing is only relevant internally
+%% for that thing.
+%%
+%% For nested things like matches the numbering continues locally and
+%% the VDB for that thing refers to the variable usage within that
+%% thing.  Variables which live through a such a thing are internally
+%% given a very large last index.  Internally the indexes continue
+%% after the index of that thing.  This creates no problems as the
+%% internal variable info never escapes and externally we only see
+%% variable which are alive both before or after.
+%%
+%% This means that variables never "escape" from a thing and the only
+%% way to get values from a thing is to "return" them, with 'break' or
+%% 'return'.  Externally these values become the return values of the
+%% thing.  This is no real limitation as most nested things have
+%% multiple threads so working out a common best variable usage is
+%% difficult.
+
+%% body(Kbody, I, Vdb) -> {[Expr],MaxI,Vdb}.
+%%  Handle a body.
+
+body(#k_seq{arg=Ke,body=Kb}, I, Vdb0) ->
+    %%ok = io:fwrite("life ~w:~p~n", [?LINE,{Ke,I,Vdb0}]),
+    A = get_kanno(Ke),
+    Vdb1 = use_vars(union(A#k.us, A#k.ns), I, Vdb0),
+    {Es,MaxI,Vdb2} = body(Kb, I+1, Vdb1),
+    E = expr(Ke, I, Vdb2),
+    {[E|Es],MaxI,Vdb2};
+body(Ke, I, Vdb0) ->
+    %%ok = io:fwrite("life ~w:~p~n", [?LINE,{Ke,I,Vdb0}]),
+    A = get_kanno(Ke),
+    Vdb1 = use_vars(union(A#k.us, A#k.ns), I, Vdb0),
+    E = expr(Ke, I, Vdb1),
+    {[E],I,Vdb1}.
+
+%% expr(Kexpr, I, Vdb) -> Expr.
+
+expr(#k_test{anno=A}=Test, I, _Vdb) ->
+    Test#k_test{anno=#l{i=I,a=A#k.a}};
+expr(#k_call{anno=A}=Call, I, _Vdb) ->
+    Call#k_call{anno=#l{i=I,a=A#k.a}};
+expr(#k_enter{anno=A}=Enter, I, _Vdb) ->
+    Enter#k_enter{anno=#l{i=I,a=A#k.a}};
+expr(#k_bif{anno=A}=Bif, I, _Vdb) ->
+    Bif#k_bif{anno=#l{i=I,a=A#k.a}};
+expr(#k_match{anno=A,body=Kb,ret=Rs}, I, Vdb) ->
+    %% Work out imported variables which need to be locked.
+    Mdb = vdb_sub(I, I+1, Vdb),
+    M = match(Kb, A#k.us, I+1, Mdb),
+    L = #l{i=I,vdb=use_vars(A#k.us, I+1, Mdb),a=A#k.a},
+    #k_match{anno=L,body=M,ret=Rs};
+expr(#k_guard_match{anno=A,body=Kb,ret=Rs}, I, Vdb) ->
+    %% Work out imported variables which need to be locked.
+    Mdb = vdb_sub(I, I+1, Vdb),
+    M = match(Kb, A#k.us, I+1, Mdb),
+    L = #l{i=I,vdb=use_vars(A#k.us, I+1, Mdb),a=A#k.a},
+    #k_guard_match{anno=L,body=M,ret=Rs};
+expr(#k_protected{}=Protected, I, Vdb) ->
+    protected(Protected, I, Vdb);
+expr(#k_try{anno=A,arg=Ka,vars=Vs,body=Kb,evars=Evs,handler=Kh}=Try, I, Vdb) ->
+    %% Lock variables that are alive before the catch and used afterwards.
+    %% Don't lock variables that are only used inside the try.
+    Tdb0 = vdb_sub(I, I+1, Vdb),
+    %% This is the tricky bit. Lock variables in Arg that are used in
+    %% the body and handler. Add try tag 'variable'.
+    Ab = get_kanno(Kb),
+    Ah = get_kanno(Kh),
+    Tdb1 = use_vars(union(Ab#k.us, Ah#k.us), I+3, Tdb0),
+    Tdb2 = vdb_sub(I, I+2, Tdb1),
+    Vnames = fun (Kvar) -> Kvar#k_var.name end,	%Get the variable names
+    {Aes,_,Adb} = body(Ka, I+2, add_var({catch_tag,I+1}, I+1, locked, Tdb2)),
+    {Bes,_,Bdb} = body(Kb, I+4, new_vars(sort(map(Vnames, Vs)), I+3, Tdb2)),
+    {Hes,_,Hdb} = body(Kh, I+4, new_vars(sort(map(Vnames, Evs)), I+3, Tdb2)),
+    L = #l{i=I,vdb=Tdb1,a=A#k.a},
+    Try#k_try{anno=L,
+              arg=#cg_block{es=Aes,anno=#l{i=I+1,vdb=Adb,a=[]}},
+              vars=Vs,body=#cg_block{es=Bes,anno=#l{i=I+3,vdb=Bdb,a=[]}},
+              evars=Evs,handler=#cg_block{es=Hes,anno=#l{i=I+3,vdb=Hdb,a=[]}}};
+expr(#k_try_enter{anno=A,arg=Ka,vars=Vs,body=Kb,evars=Evs,handler=Kh}, I, Vdb) ->
+    %% Lock variables that are alive before the catch and used afterwards.
+    %% Don't lock variables that are only used inside the try.
+    Tdb0 = vdb_sub(I, I+1, Vdb),
+    %% This is the tricky bit. Lock variables in Arg that are used in
+    %% the body and handler. Add try tag 'variable'.
+    Ab = get_kanno(Kb),
+    Ah = get_kanno(Kh),
+    Tdb1 = use_vars(union(Ab#k.us, Ah#k.us), I+3, Tdb0),
+    Tdb2 = vdb_sub(I, I+2, Tdb1),
+    Vnames = fun (Kvar) -> Kvar#k_var.name end,	%Get the variable names
+    {Aes,_,Adb} = body(Ka, I+2, add_var({catch_tag,I+1}, I+1, 1000000, Tdb2)),
+    {Bes,_,Bdb} = body(Kb, I+4, new_vars(sort(map(Vnames, Vs)), I+3, Tdb2)),
+    {Hes,_,Hdb} = body(Kh, I+4, new_vars(sort(map(Vnames, Evs)), I+3, Tdb2)),
+    L = #l{i=I,vdb=Tdb1,a=A#k.a},
+    #k_try_enter{anno=L,
+                 arg=#cg_block{es=Aes,anno=#l{i=I+1,vdb=Adb,a=[]}},
+                 vars=Vs,body=#cg_block{es=Bes,anno=#l{i=I+3,vdb=Bdb,a=[]}},
+                 evars=Evs,handler=#cg_block{es=Hes,anno=#l{i=I+3,vdb=Hdb,a=[]}}};
+expr(#k_catch{anno=A,body=Kb}=Catch, I, Vdb) ->
+    %% Lock variables that are alive before the catch and used afterwards.
+    %% Don't lock variables that are only used inside the catch.
+    %% Add catch tag 'variable'.
+    Cdb0 = vdb_sub(I, I+1, Vdb),
+    {Es,_,Cdb1} = body(Kb, I+1, add_var({catch_tag,I}, I, locked, Cdb0)),
+    L = #l{i=I,vdb=Cdb1,a=A#k.a},
+    Catch#k_catch{anno=L,body=#cg_block{es=Es}};
+expr(#k_receive{anno=A,var=V,body=Kb,action=Ka}=Recv, I, Vdb) ->
+    %% Work out imported variables which need to be locked.
+    Rdb = vdb_sub(I, I+1, Vdb),
+    M = match(Kb, add_element(V#k_var.name, A#k.us), I+1,
+              new_vars([V#k_var.name], I, Rdb)),
+    {Tes,_,Adb} = body(Ka, I+1, Rdb),
+    Le = #l{i=I,vdb=use_vars(A#k.us, I+1, Vdb),a=A#k.a},
+    Recv#k_receive{anno=Le,body=M,
+                   action=#cg_block{anno=#l{i=I+1,vdb=Adb,a=[]},es=Tes}};
+expr(#k_receive_accept{anno=A}, I, _Vdb) ->
+    #k_receive_accept{anno=#l{i=I,a=A#k.a}};
+expr(#k_receive_next{anno=A}, I, _Vdb) ->
+    #k_receive_next{anno=#l{i=I,a=A#k.a}};
+expr(#k_put{anno=A}=Put, I, _Vdb) ->
+    Put#k_put{anno=#l{i=I,a=A#k.a}};
+expr(#k_break{anno=A}=Break, I, _Vdb) ->
+    Break#k_break{anno=#l{i=I,a=A#k.a}};
+expr(#k_guard_break{anno=A}=Break, I, _Vdb) ->
+    Break#k_guard_break{anno=#l{i=I,a=A#k.a}};
+expr(#k_return{anno=A}=Ret, I, _Vdb) ->
+    Ret#k_return{anno=#l{i=I,a=A#k.a}}.
+
+%% protected(Kprotected, I, Vdb) -> Protected.
+%%  Only used in guards.
+
+protected(#k_protected{anno=A,arg=Ts}=Prot, I, Vdb) ->
+    %% Lock variables that are alive before try and used afterwards.
+    %% Don't lock variables that are only used inside the protected
+    %% expression.
+    Pdb0 = vdb_sub(I, I+1, Vdb),
+    {T,MaxI,Pdb1} = body(Ts, I+1, Pdb0),
+    Pdb2 = use_vars(A#k.ns, MaxI+1, Pdb1),	%Save "return" values
+    Prot#k_protected{arg=T,anno=#l{i=I,a=A#k.a,vdb=Pdb2}}.
+
+%% match(Kexpr, [LockVar], I, Vdb) -> Expr.
+%%  Convert match tree to old format.
+
+match(#k_alt{anno=A,first=Kf,then=Kt}, Ls, I, Vdb0) ->
+    Vdb1 = use_vars(union(A#k.us, Ls), I, Vdb0),
+    F = match(Kf, Ls, I+1, Vdb1),
+    T = match(Kt, Ls, I+1, Vdb1),
+    #k_alt{anno=[],first=F,then=T};
+match(#k_select{anno=A,types=Kts}=Select, Ls, I, Vdb0) ->
+    Vdb1 = use_vars(union(A#k.us, Ls), I, Vdb0),
+    Ts = [type_clause(Tc, Ls, I+1, Vdb1) || Tc <- Kts],
+    Select#k_select{anno=[],types=Ts};
+match(#k_guard{anno=A,clauses=Kcs}, Ls, I, Vdb0) ->
+    Vdb1 = use_vars(union(A#k.us, Ls), I, Vdb0),
+    Cs = [guard_clause(G, Ls, I+1, Vdb1) || G <- Kcs],
+    #k_guard{anno=[],clauses=Cs};
+match(Other, Ls, I, Vdb0) ->
+    Vdb1 = use_vars(Ls, I, Vdb0),
+    {B,_,Vdb2} = body(Other, I+1, Vdb1),
+    Le = #l{i=I,vdb=Vdb2,a=[]},
+    #cg_block{anno=Le,es=B}.
+
+type_clause(#k_type_clause{anno=A,type=T,values=Kvs}, Ls, I, Vdb0) ->
+    %%ok = io:format("life ~w: ~p~n", [?LINE,{T,Kvs}]),
+    Vdb1 = use_vars(union(A#k.us, Ls), I+1, Vdb0),
+    Vs = [val_clause(Vc, Ls, I+1, Vdb1) || Vc <- Kvs],
+    #k_type_clause{anno=[],type=T,values=Vs}.
+
+val_clause(#k_val_clause{anno=A,val=V,body=Kb}, Ls0, I, Vdb0) ->
+    New = (get_kanno(V))#k.ns,
+    Bus = (get_kanno(Kb))#k.us,
+    %%ok = io:format("Ls0 = ~p, Used=~p\n  New=~p, Bus=~p\n", [Ls0,Used,New,Bus]),
+    Ls1 = union(intersection(New, Bus), Ls0),	%Lock for safety
+    Vdb1 = use_vars(union(A#k.us, Ls1), I+1, new_vars(New, I, Vdb0)),
+    B = match(Kb, Ls1, I+1, Vdb1),
+    Le = #l{i=I,vdb=use_vars(Bus, I+1, Vdb1),a=A#k.a},
+    #k_val_clause{anno=Le,val=V,body=B}.
+
+guard_clause(#k_guard_clause{anno=A,guard=Kg,body=Kb}, Ls, I, Vdb0) ->
+    Vdb1 = use_vars(union(A#k.us, Ls), I+2, Vdb0),
+    Gdb = vdb_sub(I+1, I+2, Vdb1),
+    G = protected(Kg, I+1, Gdb),
+    B = match(Kb, Ls, I+2, Vdb1),
+    Le = #l{i=I,vdb=use_vars((get_kanno(Kg))#k.us, I+2, Vdb1),a=A#k.a},
+    #k_guard_clause{anno=Le,guard=G,body=B}.
+
+
+%% Here follows the code generator pass.
+%%
+%% The following assumptions have been made:
+%%
+%% 1. Matches, i.e. things with {match,M,Ret} wrappers, only return
+%% values; no variables are exported. If the match would have returned
+%% extra variables then these have been transformed to multiple return
+%% values.
+%%
+%% 2. All BIF's called in guards are gc-safe so there is no need to
+%% put thing on the stack in the guard.  While this would in principle
+%% work it would be difficult to keep track of the stack depth when
+%% trimming.
+%%
+%% The code generation uses variable lifetime information added by
+%% the previous pass to save variables, allocate registers and
+%% move registers to the stack when necessary.
+%%
+%% We try to use a consistent variable name scheme throughout.  The
+%% StackReg record is always called Bef,Int<n>,Aft.
+
 %% cg_fun([Lkexpr], [HeadVar], Vdb, State) -> {[Ainstr],State}
 
 cg_fun(Les, Hvs, Vdb, AtomMod, NameArity, Anno, St0) ->
@@ -114,18 +435,18 @@ cg_fun(Les, Hvs, Vdb, AtomMod, NameArity, Anno, St0) ->
     %% Note that and 'if_end' instruction does not need any
     %% live x registers, so it will always be safe to jump to
     %% it. (We never ever expect the jump to be taken, and in
-    %% must functions there will never be any references to
+    %% most functions there will never be any references to
     %% the label in the first place.)
     %%
 
     {UltimateMatchFail,St3} = new_label(St2),
 
     %% Create initial stack/register state, clear unused arguments.
-    Bef = clear_dead(#sr{reg=foldl(fun ({var,V}, Reg) ->
+    Bef = clear_dead(#sr{reg=foldl(fun (#k_var{name=V}, Reg) ->
 					   put_reg(V, Reg)
 				   end, [], Hvs),
 			 stk=[]}, 0, Vdb),
-    {B,_Aft,St} = cg_list(Les, 0, Vdb, Bef,
+    {B,_Aft,St} = cg_list(Les, Vdb, Bef,
 			  St3#cg{bfail=0,
 				 ultimate_failure=UltimateMatchFail,
 				 is_top_block=true}),
@@ -136,66 +457,64 @@ cg_fun(Les, Hvs, Vdb, AtomMod, NameArity, Anno, St0) ->
 
 %% cg(Lkexpr, Vdb, StackReg, State) -> {[Ainstr],StackReg,State}.
 %%  Generate code for a kexpr.
-%%  Split function into two steps for clarity, not efficiency.
-
-cg(Le, Vdb, Bef, St) ->
-    cg(Le#l.ke, Le, Vdb, Bef, St).
 
-cg({block,Es}, Le, Vdb, Bef, St) ->
+cg(#cg_block{anno=Le,es=Es}, Vdb, Bef, St) ->
     block_cg(Es, Le, Vdb, Bef, St);
-cg({match,M,Rs}, Le, Vdb, Bef, St) ->
+cg(#k_match{anno=Le,body=M,ret=Rs}, Vdb, Bef, St) ->
     match_cg(M, Rs, Le, Vdb, Bef, St);
-cg({guard_match,M,Rs}, Le, Vdb, Bef, St) ->
+cg(#k_guard_match{anno=Le,body=M,ret=Rs}, Vdb, Bef, St) ->
     guard_match_cg(M, Rs, Le, Vdb, Bef, St);
-cg({call,Func,As,Rs}, Le, Vdb, Bef, St) ->
+cg(#k_call{anno=Le,op=Func,args=As,ret=Rs}, Vdb, Bef, St) ->
     call_cg(Func, As, Rs, Le, Vdb, Bef, St);
-cg({enter,Func,As}, Le, Vdb, Bef, St) ->
+cg(#k_enter{anno=Le,op=Func,args=As}, Vdb, Bef, St) ->
     enter_cg(Func, As, Le, Vdb, Bef, St);
-cg({bif,Bif,As,Rs}, Le, Vdb, Bef, St) ->
-    bif_cg(Bif, As, Rs, Le, Vdb, Bef, St);
-cg({gc_bif,Bif,As,Rs}, Le, Vdb, Bef, St) ->
-    gc_bif_cg(Bif, As, Rs, Le, Vdb, Bef, St);
-cg({internal,Bif,As,Rs}, Le, Vdb, Bef, St) ->
-    internal_cg(Bif, As, Rs, Le, Vdb, Bef, St);
-cg({receive_loop,Te,Rvar,Rm,Tes,Rs}, Le, Vdb, Bef, St) ->
+cg(#k_bif{anno=Le}=Bif, Vdb, Bef, St) ->
+    bif_cg(Bif, Le, Vdb, Bef, St);
+cg(#k_receive{anno=Le,timeout=Te,var=Rvar,body=Rm,action=Tes,ret=Rs},
+   Vdb, Bef, St) ->
     recv_loop_cg(Te, Rvar, Rm, Tes, Rs, Le, Vdb, Bef, St);
-cg(receive_next, Le, Vdb, Bef, St) ->
+cg(#k_receive_next{anno=Le}, Vdb, Bef, St) ->
     recv_next_cg(Le, Vdb, Bef, St);
-cg(receive_accept, _Le, _Vdb, Bef, St) -> {[remove_message],Bef,St};
-cg({'try',Ta,Vs,Tb,Evs,Th,Rs}, Le, Vdb, Bef, St) ->
+cg(#k_receive_accept{}, _Vdb, Bef, St) ->
+    {[remove_message],Bef,St};
+cg(#k_try{anno=Le,arg=Ta,vars=Vs,body=Tb,evars=Evs,handler=Th,ret=Rs},
+   Vdb, Bef, St) ->
     try_cg(Ta, Vs, Tb, Evs, Th, Rs, Le, Vdb, Bef, St);
-cg({try_enter,Ta,Vs,Tb,Evs,Th}, Le, Vdb, Bef, St) ->
+cg(#k_try_enter{anno=Le,arg=Ta,vars=Vs,body=Tb,evars=Evs,handler=Th},
+   Vdb, Bef, St) ->
     try_enter_cg(Ta, Vs, Tb, Evs, Th, Le, Vdb, Bef, St);
-cg({'catch',Cb,R}, Le, Vdb, Bef, St) ->
+cg(#k_catch{anno=Le,body=Cb,ret=[R]}, Vdb, Bef, St) ->
     catch_cg(Cb, R, Le, Vdb, Bef, St);
-cg({set,Var,Con}, Le, Vdb, Bef, St) ->
-    set_cg(Var, Con, Le, Vdb, Bef, St);
-cg({return,Rs}, Le, Vdb, Bef, St) -> return_cg(Rs, Le, Vdb, Bef, St);
-cg({break,Bs}, Le, Vdb, Bef, St) -> break_cg(Bs, Le, Vdb, Bef, St);
-cg({guard_break,Bs,N}, Le, Vdb, Bef, St) ->
-    guard_break_cg(Bs, N, Le, Vdb, Bef, St);
-cg({need_heap,H}, _Le, _Vdb, Bef, St) ->
+cg(#k_put{anno=Le,arg=Con,ret=Var},  Vdb, Bef, St) ->
+    put_cg(Var, Con, Le, Vdb, Bef, St);
+cg(#k_return{anno=Le,args=Rs}, Vdb, Bef, St) ->
+    return_cg(Rs, Le, Vdb, Bef, St);
+cg(#k_break{anno=Le,args=Bs}, Vdb, Bef, St) ->
+    break_cg(Bs, Le, Vdb, Bef, St);
+cg(#k_guard_break{anno=Le,args=Bs}, Vdb, Bef, St) ->
+    guard_break_cg(Bs, Le, Vdb, Bef, St);
+cg(#cg_need_heap{h=H}, _Vdb, Bef, St) ->
     {[{test_heap,H,max_reg(Bef#sr.reg)}],Bef,St}.
 
 %% cg_list([Kexpr], FirstI, Vdb, StackReg, St) -> {[Ainstr],StackReg,St}.
 
-cg_list(Kes, I, Vdb, Bef, St0) ->
+cg_list(Kes, Vdb, Bef, St0) ->
     {Keis,{Aft,St1}} =
 	flatmapfoldl(fun (Ke, {Inta,Sta}) ->
 			     {Keis,Intb,Stb} = cg(Ke, Vdb, Inta, Sta),
 			     {Keis,{Intb,Stb}}
-		     end, {Bef,St0}, need_heap(Kes, I)),
+		     end, {Bef,St0}, need_heap(Kes)),
     {Keis,Aft,St1}.
 
 %% need_heap([Lkexpr], I, St) -> [Lkexpr].
 %%  Insert need_heap instructions in Kexpr list.  Try to be smart and
 %%  collect them together as much as possible.
 
-need_heap(Kes0, I) ->
+need_heap(Kes0) ->
     {Kes,H} = need_heap_0(reverse(Kes0), 0, []),
 
     %% Prepend need_heap if necessary.
-    need_heap_need(I, H) ++ Kes.
+    need_heap_need(H) ++ Kes.
 
 need_heap_0([Ke|Kes], H0, Acc) ->
     {Ns,H} = need_heap_1(Ke, H0),
@@ -203,27 +522,54 @@ need_heap_0([Ke|Kes], H0, Acc) ->
 need_heap_0([], H, Acc) ->
     {Acc,H}.
 
-need_heap_1(#l{ke={set,_,{binary,_}},i=I}, H) ->
-    {need_heap_need(I, H),0};
-need_heap_1(#l{ke={set,_,{map,_,_,_}},i=I}, H) ->
-    {need_heap_need(I, H),0};
-need_heap_1(#l{ke={set,_,Val}}, H) ->
+need_heap_1(#k_put{arg=#k_binary{}}, H) ->
+    {need_heap_need(H),0};
+need_heap_1(#k_put{arg=#k_map{}}, H) ->
+    {need_heap_need(H),0};
+need_heap_1(#k_put{arg=Val}, H) ->
     %% Just pass through adding to needed heap.
     {[],H + case Val of
-		{cons,_} -> 2;
-		{tuple,Es} -> 1 + length(Es);
+		#k_cons{} -> 2;
+		#k_tuple{es=Es} -> 1 + length(Es);
 		_Other -> 0
 	    end};
-need_heap_1(#l{ke={bif,_Bif,_As,_Rs}}, H) ->
-    {[],H};
-need_heap_1(#l{i=I}, H) ->
+need_heap_1(#k_bif{}=Bif, H) ->
+    case is_gc_bif(Bif) of
+        false ->
+            {[],H};
+        true ->
+            {need_heap_need(H),0}
+    end;
+need_heap_1(_Ke, H) ->
     %% Call or call-like instruction such as set_tuple_element/3.
-    {need_heap_need(I, H),0}.
-
-need_heap_need(_I, 0) -> [];
-need_heap_need(I, H) -> [#l{ke={need_heap,H},i=I}].
-
-%% match_cg(Match, [Ret], Le, Vdb, StackReg, State) ->
+    {need_heap_need(H),0}.
+
+need_heap_need(0) -> [];
+need_heap_need(H) -> [#cg_need_heap{h=H}].
+
+%% is_gc_bif(#k_bif{}) -> true|false.
+%% is_gc_bif(Name, Arity) -> true|false.
+%%  Determines whether the BIF Name/Arity might do a GC.
+
+is_gc_bif(#k_bif{op=#k_remote{name=#k_atom{val=Name}},args=Args}) ->
+    is_gc_bif(Name, length(Args));
+is_gc_bif(#k_bif{op=#k_internal{}}) ->
+    true.
+
+is_gc_bif(hd, 1) -> false;
+is_gc_bif(tl, 1) -> false;
+is_gc_bif(self, 0) -> false;
+is_gc_bif(node, 0) -> false;
+is_gc_bif(node, 1) -> false;
+is_gc_bif(element, 2) -> false;
+is_gc_bif(get, 1) -> false;
+is_gc_bif(tuple_size, 1) -> false;
+is_gc_bif(Bif, Arity) ->
+    not (erl_internal:bool_op(Bif, Arity) orelse
+	 erl_internal:new_type_test(Bif, Arity) orelse
+	 erl_internal:comp_op(Bif, Arity)).
+
+%% match_cg(Matc, [Ret], Le, Vdb, StackReg, State) ->
 %%	{[Ainstr],StackReg,State}.
 %%  Generate code for a match.  First save all variables on the stack
 %%  that are to survive after the match.  We leave saved variables in
@@ -244,7 +590,10 @@ match_cg(M, Rs, Le, Vdb, Bef, St0) ->
 guard_match_cg(M, Rs, Le, Vdb, Bef, St0) ->
     I = Le#l.i,
     {B,St1} = new_label(St0),
-    #cg{bfail=Fail} = St1,
+    Fail = case St0 of
+               #cg{bfail=0,ultimate_failure=Fail0} -> Fail0;
+               #cg{bfail=Fail0} -> Fail0
+           end,
     {Mis,Aft,St2} = match_cg(M, Fail, Bef, St1#cg{break=B}),
     %% Update the register descriptors for the return registers.
     Reg = guard_match_regs(Aft#sr.reg, Rs),
@@ -252,7 +601,7 @@ guard_match_cg(M, Rs, Le, Vdb, Bef, St0) ->
      clear_dead(Aft#sr{reg=Reg}, I, Vdb),
      St2#cg{break=St1#cg.break}}.
 
-guard_match_regs([{I,gbreakvar}|Rs], [{var,V}|Vs]) ->
+guard_match_regs([{I,gbreakvar}|Rs], [#k_var{name=V}|Vs]) ->
     [{I,V}|guard_match_regs(Rs, Vs)];
 guard_match_regs([R|Rs], Vs) ->
     [R|guard_match_regs(Rs, Vs)];
@@ -264,17 +613,14 @@ guard_match_regs([], []) -> [].
 %%  down as each level which uses this takes its own internal Vdb not
 %%  the outer one.
 
-match_cg(Le, Fail, Bef, St) ->
-    match_cg(Le#l.ke, Le, Fail, Bef, St).
-
-match_cg({alt,F,S}, _Le, Fail, Bef, St0) ->
+match_cg(#k_alt{first=F,then=S}, Fail, Bef, St0) ->
     {Tf,St1} = new_label(St0),
     {Fis,Faft,St2} = match_cg(F, Tf, Bef, St1),
     {Sis,Saft,St3} = match_cg(S, Fail, Bef, St2),
     Aft = sr_merge(Faft, Saft),
     {Fis ++ [{label,Tf}] ++ Sis,Aft,St3};
-match_cg({select,{var,Vname}=V,Scs0}, #l{a=Anno}, Fail, Bef, St) ->
-    ReuseForContext = member(reuse_for_context, Anno) andalso
+match_cg(#k_select{var=#k_var{anno=Vanno,name=Vname}=V,types=Scs0}, Fail, Bef, St) ->
+    ReuseForContext = member(reuse_for_context, Vanno) andalso
 	find_reg(Vname, Bef#sr.reg) =/= error,
     Scs = case ReuseForContext of
 	      false -> Scs0;
@@ -283,10 +629,10 @@ match_cg({select,{var,Vname}=V,Scs0}, #l{a=Anno}, Fail, Bef, St) ->
     match_fmf(fun (S, F, Sta) ->
 		      select_cg(S, V, F, Fail, Bef, Sta) end,
 	      Fail, St, Scs);
-match_cg({guard,Gcs}, _Le, Fail, Bef, St) ->
+match_cg(#k_guard{clauses=Gcs}, Fail, Bef, St) ->
     match_fmf(fun (G, F, Sta) -> guard_clause_cg(G, F, Bef, Sta) end,
 	      Fail, St, Gcs);
-match_cg({block,Es}, Le, _Fail, Bef, St) ->
+match_cg(#cg_block{anno=Le,es=Es}, _Fail, Bef, St) ->
     %% Must clear registers and stack of dead variables.
     Int = clear_dead(Bef, Le#l.i, Le#l.vdb),
     block_cg(Es, Le, Int, St).
@@ -294,8 +640,8 @@ match_cg({block,Es}, Le, _Fail, Bef, St) ->
 %% bsm_rename_ctx([Clause], Var) -> [Clause]
 %%  We know from an annotation that the register for a binary can
 %%  be reused for the match context because the two are not truly
-%%  alive at the same time (even though the conservative life time
-%%  information calculated by v3_life says so).
+%%  alive at the same time (even though the life time information
+%%  says so).
 %%
 %%  The easiest way to have those variables share the same register is
 %%  to rename the variable with the shortest life-span (the match
@@ -306,12 +652,14 @@ match_cg({block,Es}, Le, _Fail, Bef, St) ->
 %%  We must also remove all information about the match context
 %%  variable from all life-time information databases (Vdb).
 
-bsm_rename_ctx([#l{ke={type_clause,binary,
-		       [#l{ke={val_clause,{binary,{var,Old}},Ke0}}=L2]}}=L1|Cs], New) ->
+bsm_rename_ctx([#k_type_clause{type=k_binary,values=Vcs}=TC|Cs], New) ->
+    [#k_val_clause{val=#k_binary{segs=#k_var{name=Old}}=Bin,
+                   body=Ke0}=VC0] = Vcs,
     Ke = bsm_rename_ctx(Ke0, Old, New, false),
-    [L1#l{ke={type_clause,binary,
-	      [L2#l{ke={val_clause,{binary,{var,New}},Ke}}]}}|bsm_rename_ctx(Cs, New)];
-bsm_rename_ctx([C|Cs], New) -> 
+    VC = VC0#k_val_clause{val=Bin#k_binary{segs=#k_var{name=New}},
+                          body=Ke},
+    [TC#k_type_clause{values=[VC]}|bsm_rename_ctx(Cs, New)];
+bsm_rename_ctx([C|Cs], New) ->
     [C|bsm_rename_ctx(Cs, New)];
 bsm_rename_ctx([], _) -> [].
 
@@ -321,34 +669,24 @@ bsm_rename_ctx([], _) -> [].
 %%  only complicatate things to recurse into blocks not in a protected
 %%  (the match context variable is not live inside them).
 
-bsm_rename_ctx(#l{ke={select,{var,V},Cs0}}=L, Old, New, InProt) ->
+bsm_rename_ctx(#k_select{var=#k_var{name=V},types=Cs0}=Sel,
+               Old, New, InProt) ->
     Cs = bsm_rename_ctx_list(Cs0, Old, New, InProt),
-    L#l{ke={select,{var,bsm_rename_var(V, Old, New)},Cs}};
-bsm_rename_ctx(#l{ke={type_clause,Type,Cs0}}=L, Old, New, InProt) ->
+    Sel#k_select{var=#k_var{name=bsm_rename_var(V, Old, New)},types=Cs};
+bsm_rename_ctx(#k_type_clause{values=Cs0}=TC, Old, New, InProt) ->
     Cs = bsm_rename_ctx_list(Cs0, Old, New, InProt),
-    L#l{ke={type_clause,Type,Cs}};
-bsm_rename_ctx(#l{ke={val_clause,{bin_end,V},Ke0}}=L, Old, New, InProt) ->
+    TC#k_type_clause{values=Cs};
+bsm_rename_ctx(#k_val_clause{body=Ke0}=VC, Old, New, InProt) ->
     Ke = bsm_rename_ctx(Ke0, Old, New, InProt),
-    L#l{ke={val_clause,{bin_end,bsm_rename_var(V, Old, New)},Ke}};
-bsm_rename_ctx(#l{ke={val_clause,{bin_seg,V,Sz,U,Type,Fl,Vs},Ke0}}=L,
-	       Old, New, InProt) ->
-    Ke = bsm_rename_ctx(Ke0, Old, New, InProt),
-    L#l{ke={val_clause,{bin_seg,bsm_rename_var(V, Old, New),Sz,U,Type,Fl,Vs},Ke}};
-bsm_rename_ctx(#l{ke={val_clause,{bin_int,V,Sz,U,Fl,Val,Vs},Ke0}}=L,
-	       Old, New, InProt) ->
-    Ke = bsm_rename_ctx(Ke0, Old, New, InProt),
-    L#l{ke={val_clause,{bin_int,bsm_rename_var(V, Old, New),Sz,U,Fl,Val,Vs},Ke}};
-bsm_rename_ctx(#l{ke={val_clause,Val,Ke0}}=L, Old, New, InProt) ->
-    Ke = bsm_rename_ctx(Ke0, Old, New, InProt),
-    L#l{ke={val_clause,Val,Ke}};
-bsm_rename_ctx(#l{ke={alt,F0,S0}}=L, Old, New, InProt) ->
+    VC#k_val_clause{body=Ke};
+bsm_rename_ctx(#k_alt{first=F0,then=S0}=Alt, Old, New, InProt) ->
     F = bsm_rename_ctx(F0, Old, New, InProt),
     S = bsm_rename_ctx(S0, Old, New, InProt),
-    L#l{ke={alt,F,S}};
-bsm_rename_ctx(#l{ke={guard,Gcs0}}=L, Old, New, InProt) ->
+    Alt#k_alt{first=F,then=S};
+bsm_rename_ctx(#k_guard{clauses=Gcs0}=Guard, Old, New, InProt) ->
     Gcs = bsm_rename_ctx_list(Gcs0, Old, New, InProt),
-    L#l{ke={guard,Gcs}};
-bsm_rename_ctx(#l{ke={guard_clause,G0,B0}}=L, Old, New, InProt) ->
+    Guard#k_guard{clauses=Gcs};
+bsm_rename_ctx(#k_guard_clause{guard=G0,body=B0}=GC, Old, New, InProt) ->
     G = bsm_rename_ctx(G0, Old, New, InProt),
     B = bsm_rename_ctx(B0, Old, New, InProt),
     %% A guard clause may cause unsaved variables to be saved on the stack.
@@ -356,49 +694,45 @@ bsm_rename_ctx(#l{ke={guard_clause,G0,B0}}=L, Old, New, InProt) ->
     %% same register), it is neither in the stack nor register descriptor
     %% lists and we would crash when we didn't find it unless we remove
     %% it from the database.
-    bsm_forget_var(L#l{ke={guard_clause,G,B}}, Old);
-bsm_rename_ctx(#l{ke={protected,Ts0,Rs}}=L, Old, New, _InProt) ->
+    bsm_forget_var(GC#k_guard_clause{guard=G,body=B}, Old);
+bsm_rename_ctx(#k_protected{arg=Ts0}=Prot, Old, New, _InProt) ->
     InProt = true,
     Ts = bsm_rename_ctx_list(Ts0, Old, New, InProt),
-    bsm_forget_var(L#l{ke={protected,Ts,Rs}}, Old);
-bsm_rename_ctx(#l{ke={match,Ms0,Rs}}=L, Old, New, InProt) ->
+    bsm_forget_var(Prot#k_protected{arg=Ts}, Old);
+bsm_rename_ctx(#k_guard_match{body=Ms0}=Match, Old, New, InProt) ->
     Ms = bsm_rename_ctx(Ms0, Old, New, InProt),
-    L#l{ke={match,Ms,Rs}};
-bsm_rename_ctx(#l{ke={guard_match,Ms0,Rs}}=L, Old, New, InProt) ->
-    Ms = bsm_rename_ctx(Ms0, Old, New, InProt),
-    L#l{ke={guard_match,Ms,Rs}};
-bsm_rename_ctx(#l{ke={test,_,_,_}}=L, _, _, _) -> L;
-bsm_rename_ctx(#l{ke={bif,_,_,_}}=L, _, _, _) -> L;
-bsm_rename_ctx(#l{ke={gc_bif,_,_,_}}=L, _, _, _) -> L;
-bsm_rename_ctx(#l{ke={set,_,_}}=L, _, _, _) -> L;
-bsm_rename_ctx(#l{ke={call,_,_,_}}=L, _, _, _) -> L;
-bsm_rename_ctx(#l{ke={block,_}}=L, Old, _, false) ->
+    Match#k_guard_match{body=Ms};
+bsm_rename_ctx(#k_test{}=Test, _, _, _) -> Test;
+bsm_rename_ctx(#k_bif{}=Bif, _, _, _) -> Bif;
+bsm_rename_ctx(#k_put{}=Put, _, _, _) -> Put;
+bsm_rename_ctx(#k_call{}=Call, _, _, _) -> Call;
+bsm_rename_ctx(#cg_block{}=Block, Old, _, false) ->
     %% This block is not inside a protected. The match context variable cannot
     %% possibly be live inside the block.
-    bsm_forget_var(L, Old);
-bsm_rename_ctx(#l{ke={block,Bl0}}=L, Old, New, true) ->
+    bsm_forget_var(Block, Old);
+bsm_rename_ctx(#cg_block{es=Es0}=Block, Old, New, true) ->
     %% A block in a protected. We must recursively rename the variable
     %% inside the block.
-    Bl = bsm_rename_ctx_list(Bl0, Old, New, true),
-    bsm_forget_var(L#l{ke={block,Bl}}, Old);
-bsm_rename_ctx(#l{ke={guard_break,Bs,Locked0}}=L0, Old, _New, _InProt) ->
-    Locked = Locked0 -- [Old],
-    L = L0#l{ke={guard_break,Bs,Locked}},
-    bsm_forget_var(L, Old).
+    Es = bsm_rename_ctx_list(Es0, Old, New, true),
+    bsm_forget_var(Block#cg_block{es=Es}, Old);
+bsm_rename_ctx(#k_guard_break{}=Break, Old, _New, _InProt) ->
+    bsm_forget_var(Break, Old).
 
 bsm_rename_ctx_list([C|Cs], Old, New, InProt) ->
     [bsm_rename_ctx(C, Old, New, InProt)|
      bsm_rename_ctx_list(Cs, Old, New, InProt)];
 bsm_rename_ctx_list([], _, _, _) -> [].
-    
+
 bsm_rename_var(Old, Old, New) -> New;
 bsm_rename_var(V, _, _) -> V.
 
 %% bsm_forget_var(#l{}, Variable) -> #l{}
 %%  Remove a variable from the variable life-time database.
 
-bsm_forget_var(#l{vdb=Vdb}=L, V) ->
-    L#l{vdb=keydelete(V, 1, Vdb)}.
+bsm_forget_var(Ke, V) ->
+    #l{vdb=Vdb} = L0 = get_kanno(Ke),
+    L = L0#l{vdb=keydelete(V, 1, Vdb)},
+    set_kanno(Ke, L).
 
 %% block_cg([Kexpr], Le, Vdb, StackReg, St) -> {[Ainstr],StackReg,St}.
 %% block_cg([Kexpr], Le, StackReg, St) -> {[Ainstr],StackReg,St}.
@@ -407,158 +741,227 @@ block_cg(Es, Le, _Vdb, Bef, St) ->
     block_cg(Es, Le, Bef, St).
 
 block_cg(Es, Le, Bef, #cg{is_top_block=false}=St) ->
-    cg_block(Es, Le#l.i, Le#l.vdb, Bef, St);
-block_cg(Es, Le, Bef, St0) ->
-    {Is0,Aft,St} = cg_block(Es, Le#l.i, Le#l.vdb, Bef,
-			    St0#cg{is_top_block=false,need_frame=false}),
-    Is = top_level_block(Is0, Aft, max_reg(Bef#sr.reg), St),
-    {Is,Aft,St#cg{is_top_block=true}}.
-
-cg_block([], _I, _Vdb, Bef, St0) ->
+    cg_block(Es, Le#l.vdb, Bef, St);
+block_cg(Es, Le, Bef, #cg{is_top_block=true}=St0) ->
+    %% No stack frame has been established yet. Do we need one?
+    case need_stackframe(Es) of
+        true ->
+            %% We need a stack frame. Generate the code and add the
+            %% code for creating and deallocating the stack frame.
+            {Is0,Aft,St} = cg_block(Es, Le#l.vdb, Bef,
+                                    St0#cg{is_top_block=false,need_frame=false}),
+            Is = top_level_block(Is0, Aft, max_reg(Bef#sr.reg), St),
+            {Is,Aft,St#cg{is_top_block=true}};
+        false ->
+            %% This sequence of instructions ending in a #k_match{} (a
+            %% 'case' or 'if') in the Erlang code does not need a
+            %% stack frame yet. Delay the creation (if a stack frame
+            %% is needed at all, it will be created inside the
+            %% #k_match{}).
+            cg_list(Es, Le#l.vdb, Bef, St0)
+    end.
+
+%% need_stackframe([Kexpr]) -> true|false.
+%%  Does this list of instructions need a stack frame?
+%%
+%%  A sequence of instructions that don't clobber the X registers
+%%  followed by a single #k_match{} doesn't need a stack frame.
+
+need_stackframe([H|T]) ->
+    case H of
+        #k_bif{op=#k_internal{}} -> true;
+        #k_put{arg=#k_binary{}} -> true;
+        #k_bif{} -> need_stackframe(T);
+        #k_put{} -> need_stackframe(T);
+        #k_guard_match{} -> need_stackframe(T);
+        #k_match{} when T =:= [] -> false;
+        _ -> true
+    end;
+need_stackframe([]) -> false.
+
+cg_block([], _Vdb, Bef, St0) ->
     {[],Bef,St0};
-cg_block(Kes0, I, Vdb, Bef, St0) ->
+cg_block(Kes0, Vdb, Bef, St0) ->
     {Kes2,Int1,St1} =
 	case basic_block(Kes0) of
 	    {Kes1,LastI,Args,Rest} ->
-		Ke = hd(Kes1),
-		Fb = Ke#l.i,
-		cg_basic_block(Kes1, Fb, LastI, Args, Vdb, Bef, St0);
+		cg_basic_block(Kes1, LastI, Args, Vdb, Bef, St0);
 	    {Kes1,Rest} ->
-		cg_list(Kes1, I, Vdb, Bef, St0)
+		cg_list(Kes1, Vdb, Bef, St0)
 	end,
-    {Kes3,Int2,St2} = cg_block(Rest, I, Vdb, Int1, St1),
+    {Kes3,Int2,St2} = cg_block(Rest, Vdb, Int1, St1),
     {Kes2 ++ Kes3,Int2,St2}.
 
 basic_block(Kes) -> basic_block(Kes, []).
 
-basic_block([Le|Les], Acc) ->
-    case collect_block(Le#l.ke) of
-	include -> basic_block(Les, [Le|Acc]);
+basic_block([Ke|Kes], Acc) ->
+    case collect_block(Ke) of
+	include -> basic_block(Kes, [Ke|Acc]);
 	{block_end,As} ->
 	    case Acc of
 		[] ->
-		    %% If the basic block does not contain any set instructions,
+		    %% If the basic block does not contain any #k_put{} instructions,
 		    %% it serves no useful purpose to do basic block optimizations.
-		    {[Le],Les};
+		    {[Ke],Kes};
 		_ ->
-		    {reverse(Acc, [Le]),Le#l.i,As,Les}
+                    #l{i=I} = get_kanno(Ke),
+		    {reverse(Acc, [Ke]),I,As,Kes}
 	    end;
-	no_block -> {reverse(Acc, [Le]),Les}
+	no_block -> {reverse(Acc, [Ke]),Kes}
     end.
 
-%% sets that may garbage collect are not allowed in basic blocks.
-	
-collect_block({set,_,{binary,_}})    -> no_block;
-collect_block({set,_,{map,_,_,_}})   -> no_block;
-collect_block({set,_,_})             -> include;
-collect_block({call,{var,_}=Var,As,_Rs}) -> {block_end,As++[Var]};
-collect_block({call,Func,As,_Rs})   -> {block_end,As++func_vars(Func)};
-collect_block({enter,{var,_}=Var,As})-> {block_end,As++[Var]};
-collect_block({enter,Func,As})       -> {block_end,As++func_vars(Func)};
-collect_block({return,Rs})           -> {block_end,Rs};
-collect_block({break,Bs})            -> {block_end,Bs};
-collect_block(_)                     -> no_block.
-
-func_vars({remote,M,F}) when element(1, M) =:= var;
-			     element(1, F) =:= var ->
+collect_block(#k_put{arg=Arg}) ->
+    %% #k_put{} instructions that may garbage collect are not allowed
+    %% in basic blocks.
+    case Arg of
+        #k_binary{} -> no_block;
+        #k_map{} -> no_block;
+        _ -> include
+    end;
+collect_block(#k_call{op=Func,args=As}) ->
+    {block_end,As++func_vars(Func)};
+collect_block(#k_enter{op=Func,args=As}) ->
+    {block_end,As++func_vars(Func)};
+collect_block(#k_return{args=Rs}) ->
+    {block_end,Rs};
+collect_block(#k_break{args=Bs}) ->
+    {block_end,Bs};
+collect_block(_) -> no_block.
+
+func_vars(#k_var{}=Var) ->
+    [Var];
+func_vars(#k_remote{mod=M,name=F})
+  when is_record(M, k_var); is_record(F, k_var) ->
     [M,F];
 func_vars(_) -> [].
 
-%% cg_basic_block([Kexpr], FirstI, LastI, As, Vdb, StackReg, State) ->
+%% cg_basic_block([Kexpr], FirstI, LastI, Arguments, Vdb, StackReg, State) ->
 %%      {[Ainstr],StackReg,State}.
-
-cg_basic_block(Kes, Fb, Lf, As, Vdb, Bef, St0) ->
-    Res = make_reservation(As, 0),
-    Regs0 = reserve(Res, Bef#sr.reg, Bef#sr.stk),
-    Stk = extend_stack(Bef, Lf, Lf+1, Vdb),
-    Int0 = Bef#sr{reg=Regs0,stk=Stk,res=Res},
-    X0_v0 = x0_vars(As, Fb, Lf, Vdb),
-    {Keis,{Aft,_,St1}} =
+%%
+%%  Do a specialized code generation for a basic block of #put{}
+%%  instructions (that don't do any garbage collection) followed by a
+%%  call, break, or return.
+%%
+%%  'Arguments' is a list of the variables that must be loaded into
+%%  consecutive X registers before the last instruction in the block.
+%%  The point of this specialized code generation is to try put the
+%%  all of the variables in 'Arguments' into the correct X register
+%%  to begin with, instead of putting them into the first available
+%%  X register and having to move them to the correct X register
+%%  later.
+%%
+%%  To achieve that, we attempt to reserve the X registers that the
+%%  variables in 'Arguments' will need to be in when the block ends.
+%%
+%%  To make it more likely that reservations will be successful, we
+%%  will try to save variables that need to be saved to the stack as
+%%  early as possible (if an X register needed by a variable in
+%%  Arguments is occupied by another variable, the value in the
+%%  X register can be evicted if it is saved on the stack).
+%%
+%%  We will take care not to increase the size of stack frame compared
+%%  to what the standard code generator would have done (that is, to
+%%  save all X registers at the last possible moment). We will do that
+%%  by extending the stack frame to the minimal size needed to save
+%%  all that needs to be saved using extend_stack/4, and use
+%%  save_carefully/4 during code generation to only save the variables
+%%  that can be saved without growing the stack frame.
+
+cg_basic_block(Kes, Lf, As, Vdb, Bef, St0) ->
+    Int0 = reserve_arg_regs(As, Bef),
+    Int = extend_stack(Int0, Lf, Lf+1, Vdb),
+    {Keis,{Aft,St1}} =
 	flatmapfoldl(fun(Ke, St) -> cg_basic_block(Ke, St, Lf, Vdb) end,
-		     {Int0,X0_v0,St0}, need_heap(Kes, Fb)),
+		     {Int,St0}, need_heap(Kes)),
     {Keis,Aft,St1}.
 
-cg_basic_block(#l{ke={need_heap,_}}=Ke, {Inta,X0v,Sta}, _Lf, Vdb) ->
-    {Keis,Intb,Stb} = cg(Ke, Vdb, Inta, Sta),
-    {Keis, {Intb,X0v,Stb}};
-cg_basic_block(Ke, {Inta,X0_v1,Sta}, Lf, Vdb) ->
-    {Sis,Intb} = save_carefully(Inta, Ke#l.i, Lf+1, Vdb),
-    {X0_v2,Intc} = allocate_x0(X0_v1, Ke#l.i, Intb),
-    Intd = reserve(Intc),
-    {Keis,Inte,Stb} = cg(Ke, Vdb, Intd, Sta),
-    {Sis ++ Keis, {Inte,X0_v2,Stb}}.
-
-make_reservation([], _) -> [];
-make_reservation([{var,V}|As], I) -> [{I,V}|make_reservation(As, I+1)];
-make_reservation([A|As], I) -> [{I,A}|make_reservation(As, I+1)].
-
-reserve(Sr) -> Sr#sr{reg=reserve(Sr#sr.res, Sr#sr.reg, Sr#sr.stk)}.
-
-reserve([{I,V}|Rs], [free|Regs], Stk) -> [{reserved,I,V}|reserve(Rs, Regs, Stk)];
-reserve([{I,V}|Rs], [{I,V}|Regs], Stk) -> [{I,V}|reserve(Rs, Regs, Stk)];
-reserve([{I,V}|Rs], [{I,Var}|Regs], Stk) ->
+cg_basic_block(#cg_need_heap{}=Ke, {Bef,St0}, _Lf, Vdb) ->
+    {Keis,Aft,St1} = cg(Ke, Vdb, Bef, St0),
+    {Keis,{Aft,St1}};
+cg_basic_block(Ke, {Bef,St0}, Lf, Vdb) ->
+    #l{i=I} = get_kanno(Ke),
+
+    %% Save all we can to increase the possibility that reserving
+    %% registers will succeed.
+    {Sis,Int0} = save_carefully(Bef, I, Lf+1, Vdb),
+    Int1 = reserve(Int0),
+    {Keis,Aft,St1} = cg(Ke, Vdb, Int1, St0),
+    {Sis ++ Keis,{Aft,St1}}.
+
+%% reserve_arg_regs([Argument], Bef) -> Aft.
+%%  Try to reserve the X registers for all arguments. All registers
+%%  that we wish to reserve will be saved in Bef#sr.res.
+
+reserve_arg_regs(As, Bef) ->
+    Res = reserve_arg_regs_1(As, 0),
+    reserve(Bef#sr{res=Res}).
+
+reserve_arg_regs_1([#k_var{name=V}|As], I) ->
+    [{I,V}|reserve_arg_regs_1(As, I+1)];
+reserve_arg_regs_1([A|As], I) ->
+    [{I,A}|reserve_arg_regs_1(As, I+1)];
+reserve_arg_regs_1([], _) -> [].
+
+%% reserve(Bef) -> Aft.
+%%  Try to reserve more registers. The registers we wish to reserve
+%%  are found in Bef#sr.res.
+
+reserve(#sr{reg=Regs,stk=Stk,res=Res}=Sr) ->
+    Sr#sr{reg=reserve_1(Res, Regs, Stk)}.
+
+reserve_1([{I,V}|Rs], [free|Regs], Stk) ->
+    [{reserved,I,V}|reserve_1(Rs, Regs, Stk)];
+reserve_1([{I,V}|Rs], [{I,V}|Regs], Stk) ->
+    [{I,V}|reserve_1(Rs, Regs, Stk)];
+reserve_1([{I,V}|Rs], [{I,Var}|Regs], Stk) ->
     case on_stack(Var, Stk) of
-	true -> [{reserved,I,V}|reserve(Rs, Regs, Stk)];
-	false -> [{I,Var}|reserve(Rs, Regs, Stk)]
+	true -> [{reserved,I,V}|reserve_1(Rs, Regs, Stk)];
+	false -> [{I,Var}|reserve_1(Rs, Regs, Stk)]
     end;
-reserve([{I,V}|Rs], [{reserved,I,_}|Regs], Stk) ->
-    [{reserved,I,V}|reserve(Rs, Regs, Stk)];
-%reserve([{I,V}|Rs], [Other|Regs], Stk) -> [Other|reserve(Rs, Regs, Stk)];
-reserve([{I,V}|Rs], [], Stk) -> [{reserved,I,V}|reserve(Rs, [], Stk)];
-reserve([], Regs, _) -> Regs.
-
-extend_stack(Bef, Fb, Lf, Vdb) ->
-    Stk0 = clear_dead_stk(Bef#sr.stk, Fb, Vdb),
-    Saves = [V || {V,F,L} <- Vdb,
-		  F < Fb,
-		  L >= Lf,
-		  not on_stack(V, Stk0)],
-    Stk1 = foldl(fun (V, Stk) -> put_stack(V, Stk) end, Stk0, Saves),
-    Bef#sr.stk ++ lists:duplicate(length(Stk1) - length(Bef#sr.stk), free).
-
-save_carefully(Bef, Fb, Lf, Vdb) ->
-    Stk = Bef#sr.stk,
-    %% New variables that are in use but not on stack.
-    New = [VFL || {V,F,L} = VFL <- Vdb,
-		  F < Fb,
-		  L >= Lf,
-		  not on_stack(V, Stk)],
-    Saves = [V || {V,_,_} <- keysort(2, New)],
-    save_carefully(Saves, Bef, []).
-
-save_carefully([], Bef, Acc) -> {reverse(Acc),Bef};
-save_carefully([V|Vs], Bef, Acc) ->
-    case put_stack_carefully(V, Bef#sr.stk) of
-	error -> {reverse(Acc),Bef};
+reserve_1([{I,V}|Rs], [{reserved,I,_}|Regs], Stk) ->
+    [{reserved,I,V}|reserve_1(Rs, Regs, Stk)];
+reserve_1([{I,V}|Rs], [], Stk) ->
+    [{reserved,I,V}|reserve_1(Rs, [], Stk)];
+reserve_1([], Regs, _) -> Regs.
+
+%% extend_stack(Bef, FirstBefore, LastFrom, Vdb) -> Aft.
+%%  Extend the stack enough to fit all variables alive past LastFrom
+%%  and not already on the stack.
+
+extend_stack(#sr{stk=Stk0}=Bef, Fb, Lf, Vdb) ->
+    Stk1 = clear_dead_stk(Stk0, Fb, Vdb),
+    New = new_not_on_stack(Stk1, Fb, Lf, Vdb),
+    Stk2 = foldl(fun ({V,_,_}, Stk) -> put_stack(V, Stk) end, Stk1, New),
+    Stk = Stk0 ++ lists:duplicate(length(Stk2) - length(Stk0), free),
+    Bef#sr{stk=Stk}.
+
+%% save_carefully(Bef, FirstBefore, LastFrom, Vdb) -> {[SaveVar],Aft}.
+%%  Save variables which are used past current point and which are not
+%%  already on the stack, but only if the variables can be saved without
+%%  growing the stack frame.
+
+save_carefully(#sr{stk=Stk}=Bef, Fb, Lf, Vdb) ->
+    New0 = new_not_on_stack(Stk, Fb, Lf, Vdb),
+    New = keysort(2, New0),
+    save_carefully_1(New, Bef, []).
+
+save_carefully_1([{V,_,_}|Vs], #sr{reg=Regs,stk=Stk0}=Bef, Acc) ->
+    case put_stack_carefully(V, Stk0) of
+	error ->
+            {reverse(Acc),Bef};
 	Stk1 ->
-	    SrcReg = fetch_reg(V, Bef#sr.reg),
+	    SrcReg = fetch_reg(V, Regs),
 	    Move = {move,SrcReg,fetch_stack(V, Stk1)},
 	    {x,_} = SrcReg,			%Assertion - must be X register.
-	    save_carefully(Vs, Bef#sr{stk=Stk1}, [Move|Acc])
-    end.
+	    save_carefully_1(Vs, Bef#sr{stk=Stk1}, [Move|Acc])
+    end;
+save_carefully_1([], Bef, Acc) ->
+    {reverse(Acc),Bef}.
 
-x0_vars([], _Fb, _Lf, _Vdb) -> [];
-x0_vars([{var,V}|_], Fb, _Lf, Vdb) ->
-    {V,F,_L} = VFL = vdb_find(V, Vdb),
-    x0_vars1([VFL], Fb, F, Vdb);
-x0_vars([X0|_], Fb, Lf, Vdb) ->
-    x0_vars1([{X0,Lf,Lf}], Fb, Lf, Vdb).
-
-x0_vars1(X0, Fb, Xf, Vdb) ->
-    Vs0 = [VFL || {_V,F,L}=VFL <- Vdb,
-		  F >= Fb,
-		  L < Xf],
-    Vs1 = keysort(3, Vs0),
-    keysort(2, X0++Vs1).
-
-allocate_x0([], _, Bef) -> {[],Bef#sr{res=[]}};
-allocate_x0([{_,_,L}|Vs], I, Bef) when L =< I ->
-    allocate_x0(Vs, I, Bef);
-allocate_x0([{V,_F,_L}=VFL|Vs], _, Bef) ->
-    {[VFL|Vs],Bef#sr{res=reserve_x0(V, Bef#sr.res)}}.
-
-reserve_x0(V, [_|Res]) -> [{0,V}|Res];
-reserve_x0(V, []) -> [{0,V}].
+%% top_level_block([Instruction], Bef, MaxRegs, St) -> [Instruction].
+%%  For the top-level block, allocate a stack frame a necessary,
+%%  adjust Y register numbering and instructions that return
+%%  from the function.
 
 top_level_block(Keis, #sr{stk=[]}, _MaxRegs, #cg{need_frame=false}) ->
     Keis;
@@ -640,21 +1043,27 @@ turn_yreg(Other, _MaxY) ->
 %%  wrong.  These are different as in the second case there is no need
 %%  to try the next type, it will always fail.
 
-select_cg(#l{ke={type_clause,cons,[S]}}, {var,V}, Tf, Vf, Bef, St) ->
+select_cg(#k_type_clause{type=Type,values=Vs}, Var, Tf, Vf, Bef, St) ->
+    #k_var{name=V} = Var,
+    select_cg(Type, Vs, V, Tf, Vf, Bef, St).
+
+select_cg(k_cons, [S], V, Tf, Vf, Bef, St) ->
     select_cons(S, V, Tf, Vf, Bef, St);
-select_cg(#l{ke={type_clause,nil,[S]}}, {var,V}, Tf, Vf, Bef, St) ->
+select_cg(k_nil, [S], V, Tf, Vf, Bef, St) ->
     select_nil(S, V, Tf, Vf, Bef, St);
-select_cg(#l{ke={type_clause,binary,[S]}}, {var,V}, Tf, Vf, Bef, St) ->
+select_cg(k_binary, [S], V, Tf, Vf, Bef, St) ->
     select_binary(S, V, Tf, Vf, Bef, St);
-select_cg(#l{ke={type_clause,bin_seg,S}}, {var,V}, Tf, _Vf, Bef, St) ->
+select_cg(k_bin_seg, S, V, Tf, _Vf, Bef, St) ->
     select_bin_segs(S, V, Tf, Bef, St);
-select_cg(#l{ke={type_clause,bin_int,S}}, {var,V}, Tf, _Vf, Bef, St) ->
+select_cg(k_bin_int, S, V, Tf, _Vf, Bef, St) ->
     select_bin_segs(S, V, Tf, Bef, St);
-select_cg(#l{ke={type_clause,bin_end,[S]}}, {var,V}, Tf, _Vf, Bef, St) ->
+select_cg(k_bin_end, [S], V, Tf, _Vf, Bef, St) ->
     select_bin_end(S, V, Tf, Bef, St);
-select_cg(#l{ke={type_clause,map,S}}, {var,V}, Tf, Vf, Bef, St) ->
+select_cg(k_map, S, V, Tf, Vf, Bef, St) ->
     select_map(S, V, Tf, Vf, Bef, St);
-select_cg(#l{ke={type_clause,Type,Scs}}, {var,V}, Tf, Vf, Bef, St0) ->
+select_cg(k_literal, S, V, Tf, Vf, Bef, St) ->
+    select_literal(S, V, Tf, Vf, Bef, St);
+select_cg(Type, Scs, V, Tf, Vf, Bef, St0) ->
     {Vis,{Aft,St1}} =
 	mapfoldl(fun (S, {Int,Sta}) ->
 			 {Val,Is,Inta,Stb} = select_val(S, V, Vf, Bef, Sta),
@@ -664,22 +1073,29 @@ select_cg(#l{ke={type_clause,Type,Scs}}, {var,V}, Tf, Vf, Bef, St0) ->
     {Vls,Sis,St2} = select_labels(OptVls, St1, [], []),
     {select_val_cg(Type, fetch_var(V, Bef), Vls, Tf, Vf, Sis), Aft, St2}.
 
-select_val_cg(tuple, R, [Arity,{f,Lbl}], Tf, Vf, [{label,Lbl}|Sis]) ->
+select_val_cg(k_tuple, R, [Arity,{f,Lbl}], Tf, Vf, [{label,Lbl}|Sis]) ->
     [{test,is_tuple,{f,Tf},[R]},{test,test_arity,{f,Vf},[R,Arity]}|Sis];
-select_val_cg(tuple, R, Vls, Tf, Vf, Sis) ->
+select_val_cg(k_tuple, R, Vls, Tf, Vf, Sis) ->
     [{test,is_tuple,{f,Tf},[R]},{select_tuple_arity,R,{f,Vf},{list,Vls}}|Sis];
 select_val_cg(Type, R, [Val, {f,Lbl}], Fail, Fail, [{label,Lbl}|Sis]) ->
-    [{test,is_eq_exact,{f,Fail},[R,{Type,Val}]}|Sis];
+    [{test,is_eq_exact,{f,Fail},[R,{type(Type),Val}]}|Sis];
 select_val_cg(Type, R, [Val, {f,Lbl}], Tf, Vf, [{label,Lbl}|Sis]) ->
     [{test,select_type_test(Type),{f,Tf},[R]},
-     {test,is_eq_exact,{f,Vf},[R,{Type,Val}]}|Sis];
+     {test,is_eq_exact,{f,Vf},[R,{type(Type),Val}]}|Sis];
 select_val_cg(Type, R, Vls0, Tf, Vf, Sis) ->
-    Vls1 = [case Value of {f,_Lbl} -> Value; _ -> {Type,Value} end || Value <- Vls0],
+    Vls1 = [case Value of
+                {f,_Lbl} -> Value;
+                _ -> {type(Type),Value}
+            end || Value <- Vls0],
     [{test,select_type_test(Type),{f,Tf},[R]}, {select_val,R,{f,Vf},{list,Vls1}}|Sis].
-    
-select_type_test(integer) -> is_integer;
-select_type_test(atom) -> is_atom;
-select_type_test(float) -> is_float.
+
+type(k_atom) -> atom;
+type(k_float) -> float;
+type(k_int) -> integer.
+
+select_type_test(k_int) -> is_integer;
+select_type_test(k_atom) -> is_atom;
+select_type_test(k_float) -> is_float.
 
 combine([{Is,Vs1}, {Is,Vs2}|Vis]) -> combine([{Is,Vs1 ++ Vs2}|Vis]);
 combine([V|Vis]) -> [V|combine(Vis)];
@@ -695,36 +1111,49 @@ add_vls([V|Vs], Lbl, Acc) ->
     add_vls(Vs, Lbl, [V, {f,Lbl}|Acc]);
 add_vls([], _, Acc) -> Acc.
 
-select_cons(#l{ke={val_clause,{cons,Es},B},i=I,vdb=Vdb}, V, Tf, Vf, Bef, St0) ->
+select_literal(S, V, Tf, Vf, Bef, St) ->
+    Reg = fetch_var(V, Bef),
+    F = fun(ValClause, Fail, St0) ->
+                {Val,Is,Aft,St1} = select_val(ValClause, V, Vf, Bef, St0),
+                Test = {test,is_eq_exact,{f,Fail},[Reg,{literal,Val}]},
+                {[Test|Is],Aft,St1}
+        end,
+    match_fmf(F, Tf, St, S).
+
+select_cons(#k_val_clause{val=#k_cons{hd=Hd,tl=Tl},body=B,anno=#l{i=I,vdb=Vdb}},
+            V, Tf, Vf, Bef, St0) ->
+    Es = [Hd,Tl],
     {Eis,Int,St1} = select_extract_cons(V, Es, I, Vdb, Bef, St0),
     {Bis,Aft,St2} = match_cg(B, Vf, Int, St1),
     {[{test,is_nonempty_list,{f,Tf},[fetch_var(V, Bef)]}] ++ Eis ++ Bis,Aft,St2}.
 
-select_nil(#l{ke={val_clause,nil,B}}, V, Tf, Vf, Bef, St0) ->
+select_nil(#k_val_clause{val=#k_nil{},body=B}, V, Tf, Vf, Bef, St0) ->
     {Bis,Aft,St1} = match_cg(B, Vf, Bef, St0),
     {[{test,is_nil,{f,Tf},[fetch_var(V, Bef)]}] ++ Bis,Aft,St1}.
 
-select_binary(#l{ke={val_clause,{binary,{var,V}},B},i=I,vdb=Vdb},
-	      V, Tf, Vf, Bef, St0) ->
+select_binary(#k_val_clause{val=#k_binary{segs=#k_var{name=V}},body=B,
+                            anno=#l{i=I,vdb=Vdb}}, V, Tf, Vf, Bef, St0) ->
+    #cg{ctx=OldCtx} = St0,
     Int0 = clear_dead(Bef#sr{reg=Bef#sr.reg}, I, Vdb),
-    {Bis0,Aft,St1} = match_cg(B, Vf, Int0, St0),
+    {Bis0,Aft,St1} = match_cg(B, Vf, Int0, St0#cg{ctx=V}),
     CtxReg = fetch_var(V, Int0),
     Live = max_reg(Bef#sr.reg),
     Bis1 = [{test,bs_start_match2,{f,Tf},Live,[CtxReg,V],CtxReg},
 	    {bs_save2,CtxReg,{V,V}}|Bis0],
     Bis = finish_select_binary(Bis1),
-    {Bis,Aft,St1};
-select_binary(#l{ke={val_clause,{binary,{var,Ivar}},B},i=I,vdb=Vdb},
-	      V, Tf, Vf, Bef, St0) ->
+    {Bis,Aft,St1#cg{ctx=OldCtx}};
+select_binary(#k_val_clause{val=#k_binary{segs=#k_var{name=Ivar}},body=B,
+                            anno=#l{i=I,vdb=Vdb}}, V, Tf, Vf, Bef, St0) ->
+    #cg{ctx=OldCtx} = St0,
     Regs = put_reg(Ivar, Bef#sr.reg),
     Int0 = clear_dead(Bef#sr{reg=Regs}, I, Vdb),
-    {Bis0,Aft,St1} = match_cg(B, Vf, Int0, St0),
+    {Bis0,Aft,St1} = match_cg(B, Vf, Int0, St0#cg{ctx=Ivar}),
     CtxReg = fetch_var(Ivar, Int0),
     Live = max_reg(Bef#sr.reg),
     Bis1 = [{test,bs_start_match2,{f,Tf},Live,[fetch_var(V, Bef),Ivar],CtxReg},
 	    {bs_save2,CtxReg,{Ivar,Ivar}}|Bis0],
     Bis = finish_select_binary(Bis1),
-    {Bis,Aft,St1}.
+    {Bis,Aft,St1#cg{ctx=OldCtx}}.
 
 finish_select_binary([{bs_save2,R,Point}=I,{bs_restore2,R,Point}|Is]) ->
     [I|finish_select_binary(Is)];
@@ -746,9 +1175,16 @@ select_bin_segs(Scs, Ivar, Tf, Bef, St) ->
 		      select_bin_seg(S, Ivar, Fail, Bef, Sta) end,
 	      Tf, St, Scs).
 
-select_bin_seg(#l{ke={val_clause,{bin_seg,Ctx,Size,U,T,Fs0,Es},B},i=I,vdb=Vdb,a=A},
-	       Ivar, Fail, Bef, St0) ->
+select_bin_seg(#k_val_clause{val=#k_bin_seg{size=Size,unit=U,type=T,
+                                            seg=Seg,flags=Fs0,next=Next},
+                             body=B,
+                             anno=#l{i=I,vdb=Vdb,a=A}}, Ivar, Fail, Bef, St0) ->
+    Ctx = St0#cg.ctx,
     Fs = [{anno,A}|Fs0],
+    Es = case Next of
+             [] -> [Seg];
+             _ -> [Seg,Next]
+         end,
     {Mis,Int,St1} = select_extract_bin(Es, Size, U, T, Fs, Fail,
 				       I, Vdb, Bef, Ctx, B, St0),
     {Bis,Aft,St2} = match_cg(B, Fail, Int, St1),
@@ -761,9 +1197,12 @@ select_bin_seg(#l{ke={val_clause,{bin_seg,Ctx,Size,U,T,Fs0,Es},B},i=I,vdb=Vdb,a=
 		 [{bs_restore2,CtxReg,{Ctx,Ivar}}|Mis++Bis]
 	 end,
     {Is,Aft,St2};
-select_bin_seg(#l{ke={val_clause,{bin_int,Ctx,Sz,U,Fs,Val,Es},B},i=I,vdb=Vdb},
-	       Ivar, Fail, Bef, St0) ->
-    {Mis,Int,St1} = select_extract_int(Es, Val, Sz, U, Fs, Fail,
+select_bin_seg(#k_val_clause{val=#k_bin_int{size=Sz,unit=U,flags=Fs,
+                                            val=Val,next=Next},
+                             body=B,
+                             anno=#l{i=I,vdb=Vdb}}, Ivar, Fail, Bef, St0) ->
+    Ctx = St0#cg.ctx,
+    {Mis,Int,St1} = select_extract_int(Next, Val, Sz, U, Fs, Fail,
 				       I, Vdb, Bef, Ctx, St0),
     {Bis,Aft,St2} = match_cg(B, Fail, Int, St1),
     CtxReg = fetch_var(Ctx, Bef),
@@ -784,7 +1223,7 @@ select_bin_seg(#l{ke={val_clause,{bin_int,Ctx,Sz,U,Fs,Val,Es},B},i=I,vdb=Vdb},
 	 end,
     {[{bs_restore2,CtxReg,{Ctx,Ivar}}|Is],Aft,St2}.
 
-select_extract_int([{var,Tl}], Val, {integer,Sz}, U, Fs, Vf,
+select_extract_int(#k_var{name=Tl}, Val, #k_int{val=Sz}, U, Fs, Vf,
 		   I, Vdb, Bef, Ctx, St) ->
     Bits = U*Sz,
     Bin = case member(big, Fs) of
@@ -805,7 +1244,7 @@ select_extract_int([{var,Tl}], Val, {integer,Sz}, U, Fs, Vf,
 	 end,
     {Is,clear_dead(Bef, I, Vdb),St}.
 
-select_extract_bin([{var,Hd},{var,Tl}], Size0, Unit, Type, Flags, Vf,
+select_extract_bin([#k_var{name=Hd},#k_var{name=Tl}], Size0, Unit, Type, Flags, Vf,
 		   I, Vdb, Bef, Ctx, _Body, St) ->
     SizeReg = get_bin_size_reg(Size0, Bef),
     {Es,Aft} =
@@ -828,11 +1267,11 @@ select_extract_bin([{var,Hd},{var,Tl}], Size0, Unit, Type, Flags, Vf,
 		  {bs_save2,CtxReg,{Ctx,Tl}}],Int1}
 	end,
     {Es,clear_dead(Aft, I, Vdb),St};
-select_extract_bin([{var,Hd}], Size, Unit, binary, Flags, Vf,
+select_extract_bin([#k_var{name=Hd}], Size, Unit, binary, Flags, Vf,
 		   I, Vdb, Bef, Ctx, Body, St) ->
     %% Match the last segment of a binary. We KNOW that the size
     %% must be 'all'.
-    Size = {atom,all},				%Assertion.
+    #k_atom{val=all} = Size,                    %Assertion.
     {Es,Aft} =
 	case vdb_find(Hd, Vdb) of
 	    {_,_,Lhd} when Lhd =< I ->
@@ -857,7 +1296,7 @@ select_extract_bin([{var,Hd}], Size, Unit, binary, Flags, Vf,
 			Name = bs_get_binary2,
 			Live = max_reg(Bef#sr.reg),
 			{[{test,Name,{f,Vf},Live,
-			   [CtxReg,Size,Unit,{field_flags,Flags}],Rhd}],
+			   [CtxReg,atomic(Size),Unit,{field_flags,Flags}],Rhd}],
 			 Int1};
 		    true ->
 			%% Since the matching context will not be used again,
@@ -872,36 +1311,42 @@ select_extract_bin([{var,Hd}], Size, Unit, binary, Flags, Vf,
 			Name = bs_get_binary2,
 			Live = max_reg(Int1#sr.reg),
 			{[{test,Name,{f,Vf},Live,
-			   [CtxReg,Size,Unit,{field_flags,Flags}],CtxReg}],
+			   [CtxReg,atomic(Size),Unit,{field_flags,Flags}],CtxReg}],
 			 Int1}
 		end
 	end,
     {Es,clear_dead(Aft, I, Vdb),St}.
 
 %% is_context_unused(Ke) -> true | false
-%%   Simple heurististic to determine whether the code that follows will
-%%   use the current matching context again. (The information of liveness
-%%   calculcated by v3_life is too conservative to be useful for this purpose.)
-%%   'true' means that the code that follows will definitely not use the context
-%%   again (because it is a block, not guard or matching code); 'false' that we
-%%   are not sure (there is either a guard, or more matching, either which may
-%%   reference the context again).
-
-is_context_unused(#l{ke=Ke}) -> is_context_unused(Ke);
-is_context_unused({block,_}) -> true;
-is_context_unused(_) -> false.
-
-select_bin_end(#l{ke={val_clause,{bin_end,Ctx},B}},
-	       Ivar, Tf, Bef, St0) ->
+%%   Simple heurististic to determine whether the code that follows
+%%   will use the current matching context again. (The liveness
+%%   information is too conservative to be useful for this purpose.)
+%%   'true' means that the code that follows will definitely not use
+%%   the context again (because it is a block, not guard or matching
+%%   code); 'false' that we are not sure (there could be more
+%%   matching).
+
+is_context_unused(#k_alt{then=Then}) ->
+    %% #k_alt{} can be used for different purposes. If the Then part
+    %% is a block, it means that matching has finished and is used for a guard
+    %% to choose between the matched clauses.
+    is_context_unused(Then);
+is_context_unused(#cg_block{}) ->
+    true;
+is_context_unused(_) ->
+    false.
+
+select_bin_end(#k_val_clause{val=#k_bin_end{},body=B}, Ivar, Tf, Bef, St0) ->
+    Ctx = St0#cg.ctx,
     {Bis,Aft,St2} = match_cg(B, Tf, Bef, St0),
     CtxReg = fetch_var(Ctx, Bef),
     {[{bs_restore2,CtxReg,{Ctx,Ivar}},
       {test,bs_test_tail2,{f,Tf},[CtxReg,0]}|Bis],Aft,St2}.
 
-get_bin_size_reg({var,V}, Bef) ->
+get_bin_size_reg(#k_var{name=V}, Bef) ->
     fetch_var(V, Bef);
 get_bin_size_reg(Literal, _Bef) ->
-    Literal.
+    atomic(Literal).
 
 build_bs_instr(Type, Vf, CtxReg, Live, SizeReg, Unit, Flags, Rhd) ->
     {Format,Name} = case Type of
@@ -935,11 +1380,18 @@ build_skip_instr(Type, Vf, CtxReg, Live, SizeReg, Unit, Flags) ->
 	    {test,Name,{f,Vf},[CtxReg,Live,{field_flags,Flags}]}
     end.
 
-select_val(#l{ke={val_clause,{tuple,Es},B},i=I,vdb=Vdb}, V, Vf, Bef, St0) ->
+select_val(#k_val_clause{val=#k_tuple{es=Es},body=B,anno=#l{i=I,vdb=Vdb}},
+           V, Vf, Bef, St0) ->
     {Eis,Int,St1} = select_extract_tuple(V, Es, I, Vdb, Bef, St0),
     {Bis,Aft,St2} = match_cg(B, Vf, Int, St1),
     {length(Es),Eis ++ Bis,Aft,St2};
-select_val(#l{ke={val_clause,{_,Val},B}}, _V, Vf, Bef, St0) ->
+select_val(#k_val_clause{val=Val0,body=B}, _V, Vf, Bef, St0) ->
+    Val = case Val0 of
+              #k_atom{val=Lit} -> Lit;
+              #k_float{val=Lit} -> Lit;
+              #k_int{val=Lit} -> Lit;
+              #k_literal{val=Lit} -> Lit
+          end,
     {Bis,Aft,St1} = match_cg(B, Vf, Bef, St0),
     {Val,Bis,Aft,St1}.
 
@@ -948,7 +1400,7 @@ select_val(#l{ke={val_clause,{_,Val},B}}, _V, Vf, Bef, St0) ->
 %%  Extract tuple elements, but only if they do not immediately die.
 
 select_extract_tuple(Src, Vs, I, Vdb, Bef, St) ->
-    F = fun ({var,V}, {Int0,Elem}) ->
+    F = fun (#k_var{name=V}, {Int0,Elem}) ->
 		case vdb_find(V, Vdb) of
 		    {V,_,L} when L =< I -> {[], {Int0,Elem+1}};
 		    _Other ->
@@ -965,9 +1417,10 @@ select_extract_tuple(Src, Vs, I, Vdb, Bef, St) ->
 select_map(Scs, V, Tf, Vf, Bef, St0) ->
     Reg = fetch_var(V, Bef),
     {Is,Aft,St1} =
-	match_fmf(fun(#l{ke={val_clause,{map,exact,_,Es},B},i=I,vdb=Vdb}, Fail, St1) ->
-			  select_map_val(V, Es, B, Fail, I, Vdb, Bef, St1)
-		  end, Vf, St0, Scs),
+	match_fmf(fun(#k_val_clause{val=#k_map{op=exact,es=Es},
+                                    body=B,anno=#l{i=I,vdb=Vdb}}, Fail, St1) ->
+                          select_map_val(V, Es, B, Fail, I, Vdb, Bef, St1)
+                  end, Vf, St0, Scs),
     {[{test,is_map,{f,Tf},[Reg]}|Is],Aft,St1}.
 
 select_map_val(V, Es, B, Fail, I, Vdb, Bef, St0) ->
@@ -984,29 +1437,32 @@ select_extract_map(Src, Vs, Fail, I, Vdb, Bef, St) ->
     %% Assume keys are term-sorted
     Rsrc = fetch_var(Src, Bef),
 
-    {{HasKs,GetVs,HasVarKs,GetVarVs},Aft} = lists:foldr(fun
-	    ({map_pair,{var,K},{var,V}},{{HasKsi,GetVsi,HasVarVsi,GetVarVsi},Int0}) ->
-		case vdb_find(V, Vdb) of
-		    {V,_,L} when L =< I ->
-			RK = fetch_var(K,Int0),
-			{{HasKsi,GetVsi,[RK|HasVarVsi],GetVarVsi},Int0};
-		    _Other ->
-			Reg1 = put_reg(V, Int0#sr.reg),
-			Int1 = Int0#sr{reg=Reg1},
-			RK = fetch_var(K,Int0),
-			RV = fetch_reg(V,Reg1),
-			{{HasKsi,GetVsi,HasVarVsi,[[RK,RV]|GetVarVsi]},Int1}
-		end;
-	    ({map_pair,Key,{var,V}},{{HasKsi,GetVsi,HasVarVsi,GetVarVsi},Int0}) ->
-		case vdb_find(V, Vdb) of
-		    {V,_,L} when L =< I ->
-			{{[Key|HasKsi],GetVsi,HasVarVsi,GetVarVsi},Int0};
-		    _Other ->
-			Reg1 = put_reg(V, Int0#sr.reg),
-			Int1 = Int0#sr{reg=Reg1},
-			{{HasKsi,[Key,fetch_reg(V, Reg1)|GetVsi],HasVarVsi,GetVarVsi},Int1}
-		end
-	end, {{[],[],[],[]},Bef}, Vs),
+    {{HasKs,GetVs,HasVarKs,GetVarVs},Aft} =
+        foldr(fun(#k_map_pair{key=#k_var{name=K},val=#k_var{name=V}},
+                  {{HasKsi,GetVsi,HasVarVsi,GetVarVsi},Int0}) ->
+                      case vdb_find(V, Vdb) of
+                          {V,_,L} when L =< I ->
+                              RK = fetch_var(K,Int0),
+                              {{HasKsi,GetVsi,[RK|HasVarVsi],GetVarVsi},Int0};
+                          _Other ->
+                              Reg1 = put_reg(V, Int0#sr.reg),
+                              Int1 = Int0#sr{reg=Reg1},
+                              RK = fetch_var(K,Int0),
+                              RV = fetch_reg(V,Reg1),
+                              {{HasKsi,GetVsi,HasVarVsi,[[RK,RV]|GetVarVsi]},Int1}
+                      end;
+                 (#k_map_pair{key=Key,val=#k_var{name=V}},
+                  {{HasKsi,GetVsi,HasVarVsi,GetVarVsi},Int0}) ->
+                      case vdb_find(V, Vdb) of
+                          {V,_,L} when L =< I ->
+                              {{[atomic(Key)|HasKsi],GetVsi,HasVarVsi,GetVarVsi},Int0};
+                          _Other ->
+                              Reg1 = put_reg(V, Int0#sr.reg),
+                              Int1 = Int0#sr{reg=Reg1},
+                              {{HasKsi,[atomic(Key),fetch_reg(V, Reg1)|GetVsi],
+                                HasVarVsi,GetVarVsi},Int1}
+                      end
+              end, {{[],[],[],[]},Bef}, Vs),
 
     Code = [{test,has_map_fields,{f,Fail},Rsrc,{list,HasKs}} || HasKs =/= []] ++
 	   [{test,has_map_fields,{f,Fail},Rsrc,{list,[K]}}   || K <- HasVarKs] ++
@@ -1015,7 +1471,7 @@ select_extract_map(Src, Vs, Fail, I, Vdb, Bef, St) ->
     {Code, Aft, St}.
 
 
-select_extract_cons(Src, [{var,Hd}, {var,Tl}], I, Vdb, Bef, St) ->
+select_extract_cons(Src, [#k_var{name=Hd}, #k_var{name=Tl}], I, Vdb, Bef, St) ->
     {Es,Aft} = case {vdb_find(Hd, Vdb), vdb_find(Tl, Vdb)} of
 		   {{_,_,Lhd}, {_,_,Ltl}} when Lhd =< I, Ltl =< I ->
 		       %% Both head and tail are dead.  No need to generate
@@ -1038,7 +1494,7 @@ select_extract_cons(Src, [{var,Hd}, {var,Tl}], I, Vdb, Bef, St) ->
     {Es,Aft,St}.
     
 
-guard_clause_cg(#l{ke={guard_clause,G,B},vdb=Vdb}, Fail, Bef, St0) ->
+guard_clause_cg(#k_guard_clause{anno=#l{vdb=Vdb},guard=G,body=B}, Fail, Bef, St0) ->
     {Gis,Int,St1} = guard_cg(G, Fail, Vdb, Bef, St0),
     {Bis,Aft,St} = match_cg(B, Fail, Int, St1),
     {Gis ++ Bis,Aft,St}.
@@ -1051,11 +1507,11 @@ guard_clause_cg(#l{ke={guard_clause,G,B},vdb=Vdb}, Fail, Bef, St0) ->
 %%  the correct exit point.  Primops and tests all go to the next
 %%  instruction on success or jump to a failure label.
 
-guard_cg(#l{ke={protected,Ts,Rs},i=I,vdb=Pdb}, Fail, _Vdb, Bef, St) ->
-    protected_cg(Ts, Rs, Fail, I, Pdb, Bef, St);
-guard_cg(#l{ke={block,Ts},i=I,vdb=Bdb}, Fail, _Vdb, Bef, St) ->
-    guard_cg_list(Ts, Fail, I, Bdb, Bef, St);
-guard_cg(#l{ke={test,Test,As,Inverted},i=I,vdb=_Tdb}, Fail, Vdb, Bef, St0) ->
+guard_cg(#k_protected{arg=Ts,ret=Rs,anno=#l{vdb=Pdb}}, Fail, _Vdb, Bef, St) ->
+    protected_cg(Ts, Rs, Fail, Pdb, Bef, St);
+guard_cg(#k_test{anno=#l{i=I},op=Test0,args=As,inverted=Inverted},
+         Fail, Vdb, Bef, St0) ->
+    #k_remote{mod=#k_atom{val=erlang},name=#k_atom{val=Test}} = Test0,
     case Inverted of
 	false ->
 	    test_cg(Test, As, Fail, I, Vdb, Bef, St0);
@@ -1070,6 +1526,18 @@ guard_cg(G, _Fail, Vdb, Bef, St) ->
     %%ok = io:fwrite("cg ~w: ~p~n", [?LINE,{Aft}]),
     {Gis,Aft,St1}.
 
+%% guard_cg_list([Kexpr], Fail, I, Vdb, StackReg, St) ->
+%%      {[Ainstr],StackReg,St}.
+
+guard_cg_list(Kes, Fail, Vdb, Bef, St0) ->
+    {Keis,{Aft,St1}} =
+	flatmapfoldl(fun (Ke, {Inta,Sta}) ->
+			     {Keis,Intb,Stb} =
+				 guard_cg(Ke, Fail, Vdb, Inta, Sta),
+			     {Keis,{Intb,Stb}}
+		     end, {Bef,St0}, need_heap(Kes)),
+    {Keis,Aft,St1}.
+
 %% protected_cg([Kexpr], [Ret], Fail, I, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
 %%  Do a protected.  Protecteds without return values are just done
 %%  for effect, the return value is not checked, success passes on to
@@ -1077,19 +1545,18 @@ guard_cg(G, _Fail, Vdb, Bef, St) ->
 %%  return values then these must be set to 'false' on failure,
 %%  control always passes to the next instruction.
 
-protected_cg(Ts, [], Fail, I, Vdb, Bef, St0) ->
+protected_cg(Ts, [], Fail, Vdb, Bef, St0) ->
     %% Protect these calls, revert when done.
-    {Tis,Aft,St1} = guard_cg_list(Ts, Fail, I, Vdb, Bef,
-				  St0#cg{bfail=Fail}),
+    {Tis,Aft,St1} = guard_cg_list(Ts, Fail, Vdb, Bef, St0#cg{bfail=Fail}),
     {Tis,Aft,St1#cg{bfail=St0#cg.bfail}};
-protected_cg(Ts, Rs, _Fail, I, Vdb, Bef, St0) ->
+protected_cg(Ts, Rs, _Fail, Vdb, Bef, St0) ->
     {Pfail,St1} = new_label(St0),
     {Psucc,St2} = new_label(St1),
-    {Tis,Aft,St3} = guard_cg_list(Ts, Pfail, I, Vdb, Bef,
+    {Tis,Aft,St3} = guard_cg_list(Ts, Pfail, Vdb, Bef,
 				  St2#cg{bfail=Pfail}),
     %%ok = io:fwrite("cg ~w: ~p~n", [?LINE,{Rs,I,Vdb,Aft}]),
     %% Set return values to false.
-    Mis = [{move,{atom,false},fetch_var(V,Aft)}||{var,V} <- Rs],
+    Mis = [{move,{atom,false},fetch_var(V,Aft)}||#k_var{name=V} <- Rs],
     {Tis ++ [{jump,{f,Psucc}},
 	     {label,Pfail}] ++ Mis ++ [{label,Psucc}],
      Aft,St3#cg{bfail=St0#cg.bfail}}.    
@@ -1114,7 +1581,7 @@ test_cg(is_map, [A], Fail, I, Vdb, Bef, St) ->
     Arg = cg_reg_arg_prefer_y(A, Bef),
     Aft = clear_dead(Bef, I, Vdb),
     {[{test,is_map,{f,Fail},[Arg]}],Aft,St};
-test_cg(is_boolean, [{atom,Val}], Fail, I, Vdb, Bef, St) ->
+test_cg(is_boolean, [#k_atom{val=Val}], Fail, I, Vdb, Bef, St) ->
     Aft = clear_dead(Bef, I, Vdb),
     Is = case is_boolean(Val) of
 	     true -> [];
@@ -1126,18 +1593,6 @@ test_cg(Test, As, Fail, I, Vdb, Bef, St) ->
     Aft = clear_dead(Bef, I, Vdb),
     {[beam_utils:bif_to_test(Test, Args, {f,Fail})],Aft,St}.
 
-%% guard_cg_list([Kexpr], Fail, I, Vdb, StackReg, St) ->
-%%      {[Ainstr],StackReg,St}.
-
-guard_cg_list(Kes, Fail, I, Vdb, Bef, St0) ->
-    {Keis,{Aft,St1}} =
-	flatmapfoldl(fun (Ke, {Inta,Sta}) ->
-			     {Keis,Intb,Stb} =
-				 guard_cg(Ke, Fail, Vdb, Inta, Sta),
-			     {Keis,{Intb,Stb}}
-		     end, {Bef,St0}, need_heap(Kes, I)),
-    {Keis,Aft,St1}.
-
 %% match_fmf(Fun, LastFail, State, [Clause]) -> {Is,Aft,State}.
 %%  This is a special flatmapfoldl for match code gen where we
 %%  generate a "failure" label for each clause. The last clause uses
@@ -1160,7 +1615,7 @@ match_fmf(F, LastFail, St0, [H|T]) ->
 %%  frame size. Finally the actual call is made.  Call then needs the
 %%  return values filled in.
 
-call_cg({var,_V} = Var, As, Rs, Le, Vdb, Bef, St0) ->
+call_cg(#k_var{}=Var, As, Rs, Le, Vdb, Bef, St0) ->
     {Sis,Int} = cg_setup_call(As++[Var], Bef, Le#l.i, Vdb),
     %% Put return values in registers.
     Reg = load_vars(Rs, clear_regs(Int#sr.reg)),
@@ -1169,9 +1624,8 @@ call_cg({var,_V} = Var, As, Rs, Le, Vdb, Bef, St0) ->
     {Frees,Aft} = free_dead(clear_dead(Int#sr{reg=Reg}, Le#l.i, Vdb)),
     {Sis ++ Frees ++ [line(Le),{call_fun,Arity}],Aft,
      need_stack_frame(St0)};
-call_cg({remote,Mod,Name}, As, Rs, Le, Vdb, Bef, St0)
-  when element(1, Mod) =:= var;
-       element(1, Name) =:= var ->
+call_cg(#k_remote{mod=Mod,name=Name}, As, Rs, Le, Vdb, Bef, St0)
+  when is_record(Mod, k_var); is_record(Name, k_var) ->
     {Sis,Int} = cg_setup_call(As++[Mod,Name], Bef, Le#l.i, Vdb),
     %% Put return values in registers.
     Reg = load_vars(Rs, clear_regs(Int#sr.reg)),
@@ -1189,8 +1643,9 @@ call_cg(Func, As, Rs, Le, Vdb, Bef, St0) ->
 	    %%
 	    %%     move {atom,ok} DestReg
 	    %%     jump FailureLabel
-	    {remote,{atom,erlang},{atom,error}} = Func,	%Assertion.
-	    [{var,DestVar}] = Rs,
+	    #k_remote{mod=#k_atom{val=erlang},
+                      name=#k_atom{val=error}} = Func, %Assertion.
+	    [#k_var{name=DestVar}] = Rs,
 	    Int0 = clear_dead(Bef, Le#l.i, Vdb),
 	    Reg = put_reg(DestVar, Int0#sr.reg),
 	    Int = Int0#sr{reg=Reg},
@@ -1209,11 +1664,11 @@ call_cg(Func, As, Rs, Le, Vdb, Bef, St0) ->
 	    {Sis ++ Frees ++ [line(Le)|Call],Aft,St1}
     end.
 
-build_call({remote,{atom,erlang},{atom,'!'}}, 2, St0) ->
+build_call(#k_remote{mod=#k_atom{val=erlang},name=#k_atom{val='!'}}, 2, St0) ->
     {[send],need_stack_frame(St0)};
-build_call({remote,{atom,Mod},{atom,Name}}, Arity, St0) ->
+build_call(#k_remote{mod=#k_atom{val=Mod},name=#k_atom{val=Name}}, Arity, St0) ->
     {[{call_ext,Arity,{extfunc,Mod,Name,Arity}}],need_stack_frame(St0)};
-build_call(Name, Arity, St0) when is_atom(Name) ->
+build_call(#k_local{name=Name}, Arity, St0) when is_atom(Name) ->
     {Lbl,St1} = local_func_label(Name, Arity, need_stack_frame(St0)),
     {[{call,Arity,{f,Lbl}}],St1}.
 
@@ -1229,16 +1684,15 @@ free_dead([Any|Stk], Y, Instr, StkAcc) ->
     free_dead(Stk, Y+1, Instr, [Any|StkAcc]);
 free_dead([], _, Instr, StkAcc) -> {Instr,reverse(StkAcc)}.
 
-enter_cg({var,_V} = Var, As, Le, Vdb, Bef, St0) ->
+enter_cg(#k_var{} = Var, As, Le, Vdb, Bef, St0) ->
     {Sis,Int} = cg_setup_call(As++[Var], Bef, Le#l.i, Vdb),
     %% Build complete code and final stack/register state.
     Arity = length(As),
     {Sis ++ [line(Le),{call_fun,Arity},return],
      clear_dead(Int#sr{reg=clear_regs(Int#sr.reg)}, Le#l.i, Vdb),
      need_stack_frame(St0)};
-enter_cg({remote,Mod,Name}, As, Le, Vdb, Bef, St0)
-  when element(1, Mod) =:= var;
-       element(1, Name) =:= var ->
+enter_cg(#k_remote{mod=Mod,name=Name}, As, Le, Vdb, Bef, St0)
+  when is_record(Mod, k_var); is_record(Name, k_var) ->
     {Sis,Int} = cg_setup_call(As++[Mod,Name], Bef, Le#l.i, Vdb),
     %% Build complete code and final stack/register state.
     Arity = length(As),
@@ -1256,19 +1710,19 @@ enter_cg(Func, As, Le, Vdb, Bef, St0) ->
      clear_dead(Int#sr{reg=clear_regs(Int#sr.reg)}, Le#l.i, Vdb),
      St1}.
 
-build_enter({remote,{atom,erlang},{atom,'!'}}, 2, St0) ->
+build_enter(#k_remote{mod=#k_atom{val=erlang},name=#k_atom{val='!'}}, 2, St0) ->
     {[send,return],need_stack_frame(St0)};
-build_enter({remote,{atom,Mod},{atom,Name}}, Arity, St0) ->
+build_enter(#k_remote{mod=#k_atom{val=Mod},name=#k_atom{val=Name}}, Arity, St0) ->
     St1 = case trap_bif(Mod, Name, Arity) of
 	      true -> need_stack_frame(St0);
 	      false -> St0
 	  end,
     {[{call_ext_only,Arity,{extfunc,Mod,Name,Arity}}],St1};
-build_enter(Name, Arity, St0) when is_atom(Name) ->
+build_enter(#k_local{name=Name}, Arity, St0) when is_atom(Name) ->
     {Lbl,St1} = local_func_label(Name, Arity, St0),
     {[{call_only,Arity,{f,Lbl}}],St1}.
 
-enter_line({remote,{atom,Mod},{atom,Name}}, Arity, Le) ->
+enter_line(#k_remote{mod=#k_atom{val=Mod},name=#k_atom{val=Name}}, Arity, Le) ->
     case erl_bifs:is_safe(Mod, Name, Arity) of
 	false ->
 	    %% Tail-recursive call, possibly to a BIF.
@@ -1316,17 +1770,28 @@ trap_bif(erlang, group_leader, 2) -> true;
 trap_bif(erlang, exit, 2) -> true;
 trap_bif(_, _, _) -> false.
 
+%% bif_cg(#k_bif{}, Le, Vdb, StackReg, State) ->
+%%      {[Ainstr],StackReg,State}.
+%%  Generate code a BIF.
+
+bif_cg(#k_bif{op=#k_internal{name=Name},args=As,ret=Rs}, Le, Vdb, Bef, St) ->
+    internal_cg(Name, As, Rs, Le, Vdb, Bef, St);
+bif_cg(#k_bif{op=#k_remote{mod=#k_atom{val=erlang},name=#k_atom{val=Name}},
+              args=As,ret=Rs}, Le, Vdb, Bef, St) ->
+    Ar = length(As),
+    case is_gc_bif(Name, Ar) of
+	false ->
+            bif_cg(Name, As, Rs, Le, Vdb, Bef, St);
+	true ->
+            gc_bif_cg(Name, As, Rs, Le, Vdb, Bef, St)
+    end.
+
 %% internal_cg(Bif, [Arg], [Ret], Le, Vdb, StackReg, State) ->
 %%      {[Ainstr],StackReg,State}.
 
 internal_cg(bs_context_to_binary=Instr, [Src0], [], Le, Vdb, Bef, St0) ->
     [Src] = cg_reg_args([Src0], Bef),
-    case is_register(Src) of
-	false ->
-	    {[],clear_dead(Bef, Le#l.i, Vdb), St0};
-	true ->
-	    {[{Instr,Src}],clear_dead(Bef, Le#l.i, Vdb), St0}
-    end;
+    {[{Instr,Src}],clear_dead(Bef, Le#l.i, Vdb), St0};
 internal_cg(dsetelement, [Index0,Tuple0,New0], _Rs, Le, Vdb, Bef, St0) ->
     [New,Tuple,{integer,Index1}] = cg_reg_args([New0,Tuple0,Index0], Bef),
     Index = Index1-1,
@@ -1334,8 +1799,8 @@ internal_cg(dsetelement, [Index0,Tuple0,New0], _Rs, Le, Vdb, Bef, St0) ->
      clear_dead(Bef, Le#l.i, Vdb), St0};
 internal_cg(make_fun, [Func0,Arity0|As], Rs, Le, Vdb, Bef, St0) ->
     %% This behaves more like a function call.
-    {atom,Func} = Func0,
-    {integer,Arity} = Arity0,
+    #k_atom{val=Func} = Func0,
+    #k_int{val=Arity} = Arity0,
     {Sis,Int} = cg_setup_call(As, Bef, Le#l.i, Vdb),
     Reg = load_vars(Rs, clear_regs(Int#sr.reg)),
     {FuncLbl,St1} = local_func_label(Func, Arity, St0),
@@ -1348,6 +1813,11 @@ internal_cg(bs_init_writable=I, As, Rs, Le, Vdb, Bef, St) ->
     {Sis,Int} = cg_setup_call(As, Bef, Le#l.i, Vdb),
     Reg = load_vars(Rs, clear_regs(Int#sr.reg)),
     {Sis++[I],clear_dead(Int#sr{reg=Reg}, Le#l.i, Vdb),St};
+internal_cg(build_stacktrace=I, As, Rs, Le, Vdb, Bef, St) ->
+    %% This behaves like a function call.
+    {Sis,Int} = cg_setup_call(As, Bef, Le#l.i, Vdb),
+    Reg = load_vars(Rs, clear_regs(Int#sr.reg)),
+    {Sis++[I],clear_dead(Int#sr{reg=Reg}, Le#l.i, Vdb),St};
 internal_cg(raise, As, Rs, Le, Vdb, Bef, St) ->
     %% raise can be treated like a guard BIF.
     bif_cg(raise, As, Rs, Le, Vdb, Bef, St).
@@ -1355,7 +1825,7 @@ internal_cg(raise, As, Rs, Le, Vdb, Bef, St) ->
 %% bif_cg(Bif, [Arg], [Ret], Le, Vdb, StackReg, State) ->
 %%      {[Ainstr],StackReg,State}.
 
-bif_cg(Bif, As, [{var,V}], Le, Vdb, Bef, St0) ->
+bif_cg(Bif, As, [#k_var{name=V}], Le, Vdb, Bef, St0) ->
     Ars = cg_reg_args(As, Bef),
 
     %% If we are inside a catch and in a body (not in guard) and the
@@ -1393,7 +1863,7 @@ bif_cg(Bif, As, [{var,V}], Le, Vdb, Bef, St0) ->
 %% gc_bif_cg(Bif, [Arg], [Ret], Le, Vdb, StackReg, State) ->
 %%      {[Ainstr],StackReg,State}.
 
-gc_bif_cg(Bif, As, [{var,V}], Le, Vdb, Bef, St0) ->
+gc_bif_cg(Bif, As, [#k_var{name=V}], Le, Vdb, Bef, St0) ->
     Ars = cg_reg_args(As, Bef),
 
     %% If we are inside a catch and in a body (not in guard) and the
@@ -1439,7 +1909,7 @@ recv_loop_cg(Te, Rvar, Rm, Tes, Rs, Le, Vdb, Bef, St0) ->
 
 %% cg_recv_mesg( ) -> {[Ainstr],Aft,St}.
 
-cg_recv_mesg({var,R}, Rm, Tl, Bef, St0) ->
+cg_recv_mesg(#k_var{name=R}, Rm, Tl, Bef, St0) ->
     Int0 = Bef#sr{reg=put_reg(R, Bef#sr.reg)},
     Ret = fetch_reg(R, Int0#sr.reg),
     %% Int1 = clear_dead(Int0, I, Rm#l.vdb),
@@ -1449,22 +1919,22 @@ cg_recv_mesg({var,R}, Rm, Tl, Bef, St0) ->
 
 %% cg_recv_wait(Te, Tes, I, Vdb, Int2, St3) -> {[Ainstr],Aft,St}.
 
-cg_recv_wait({atom,infinity}, Tes, I, Bef, St0) ->
+cg_recv_wait(#k_atom{val=infinity}, #cg_block{anno=Le,es=Tes}, I, Bef, St0) ->
     %% We know that the 'after' body will never be executed.
     %% But to keep the stack and register information up to date,
     %% we will generate the code for the 'after' body, and then discard it.
-    Int1 = clear_dead(Bef, I, Tes#l.vdb),
-    {_,Int2,St1} = cg_block(Tes#l.ke, Tes#l.i, Tes#l.vdb,
-			      Int1#sr{reg=clear_regs(Int1#sr.reg)}, St0),
+    Int1 = clear_dead(Bef, I, Le#l.vdb),
+    {_,Int2,St1} = cg_block(Tes, Le#l.vdb,
+                            Int1#sr{reg=clear_regs(Int1#sr.reg)}, St0),
     {[{wait,{f,St1#cg.recv}}],Int2,St1};
-cg_recv_wait({integer,0}, Tes, _I, Bef, St0) ->
-    {Tis,Int,St1} = cg_block(Tes#l.ke, Tes#l.i, Tes#l.vdb, Bef, St0),
+cg_recv_wait(#k_int{val=0}, #cg_block{anno=Le,es=Tes}, _I, Bef, St0) ->
+    {Tis,Int,St1} = cg_block(Tes, Le#l.vdb, Bef, St0),
     {[timeout|Tis],Int,St1};
-cg_recv_wait(Te, Tes, I, Bef, St0) ->
+cg_recv_wait(Te, #cg_block{anno=Le,es=Tes}, I, Bef, St0) ->
     Reg = cg_reg_arg(Te, Bef),
     %% Must have empty registers here!  Bug if anything in registers.
-    Int0 = clear_dead(Bef, I, Tes#l.vdb),
-    {Tis,Int,St1} = cg_block(Tes#l.ke, Tes#l.i, Tes#l.vdb,
+    Int0 = clear_dead(Bef, I, Le#l.vdb),
+    {Tis,Int,St1} = cg_block(Tes, Le#l.vdb,
 			     Int0#sr{reg=clear_regs(Int0#sr.reg)}, St0),
     {[{wait_timeout,{f,St1#cg.recv},Reg},timeout] ++ Tis,Int,St1}.
 
@@ -1482,7 +1952,7 @@ try_cg(Ta, Vs, Tb, Evs, Th, Rs, Le, Vdb, Bef, St0) ->
     {B,St1} = new_label(St0),			%Body label
     {H,St2} = new_label(St1),			%Handler label
     {E,St3} = new_label(St2),			%End label
-    TryTag = Ta#l.i,
+    #l{i=TryTag} = get_kanno(Ta),
     Int1 = Bef#sr{stk=put_catch(TryTag, Bef#sr.stk)},
     TryReg = fetch_stack({catch_tag,TryTag}, Int1#sr.stk),
     {Ais,Int2,St4} = cg(Ta, Vdb, Int1, St3#cg{break=B,in_catch=true}),
@@ -1502,7 +1972,7 @@ try_cg(Ta, Vs, Tb, Evs, Th, Rs, Le, Vdb, Bef, St0) ->
 try_enter_cg(Ta, Vs, Tb, Evs, Th, Le, Vdb, Bef, St0) ->
     {B,St1} = new_label(St0),			%Body label
     {H,St2} = new_label(St1),			%Handler label
-    TryTag = Ta#l.i,
+    #l{i=TryTag} = get_kanno(Ta),
     Int1 = Bef#sr{stk=put_catch(TryTag, Bef#sr.stk)},
     TryReg = fetch_stack({catch_tag,TryTag}, Int1#sr.stk),
     {Ais,Int2,St3} = cg(Ta, Vdb, Int1, St2#cg{break=B,in_catch=true}),
@@ -1520,12 +1990,12 @@ try_enter_cg(Ta, Vs, Tb, Evs, Th, Le, Vdb, Bef, St0) ->
 
 %% catch_cg(CatchBlock, Ret, Le, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
 
-catch_cg(C, {var,R}, Le, Vdb, Bef, St0) ->
+catch_cg(#cg_block{es=C}, #k_var{name=R}, Le, Vdb, Bef, St0) ->
     {B,St1} = new_label(St0),
     CatchTag = Le#l.i,
     Int1 = Bef#sr{stk=put_catch(CatchTag, Bef#sr.stk)},
     CatchReg = fetch_stack({catch_tag,CatchTag}, Int1#sr.stk),
-    {Cis,Int2,St2} = cg_block(C, Le#l.i, Le#l.vdb, Int1,
+    {Cis,Int2,St2} = cg_block(C, Le#l.vdb, Int1,
 			      St1#cg{break=B,in_catch=true}),
     [] = Int2#sr.reg,				%Assertion.
     Aft = Int2#sr{reg=[{0,R}],stk=drop_catch(CatchTag, Int2#sr.stk)},
@@ -1534,8 +2004,8 @@ catch_cg(C, {var,R}, Le, Vdb, Bef, St0) ->
      clear_dead(Aft, Le#l.i, Vdb),
      St2#cg{break=St1#cg.break,in_catch=St1#cg.in_catch}}.
 
-%% set_cg([Var], Constr, Le, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
-%%  We have to be careful how a 'set' works. First the structure is
+%% put_cg([Var], Constr, Le, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
+%%  We have to be careful how a 'put' works. First the structure is
 %%  built, then it is filled and finally things can be cleared. The
 %%  annotation must reflect this and make sure that the return
 %%  variable is allocated first.
@@ -1543,13 +2013,14 @@ catch_cg(C, {var,R}, Le, Vdb, Bef, St0) ->
 %%  put_list and put_map are atomic instructions, both of
 %%  which can safely resuse one of the source registers as target.
 
-set_cg([{var,R}], {cons,Es}, Le, Vdb, Bef, St) ->
-    [S1,S2] = cg_reg_args(Es, Bef),
+put_cg([#k_var{name=R}], #k_cons{hd=Hd,tl=Tl}, Le, Vdb, Bef, St) ->
+    [S1,S2] = cg_reg_args([Hd,Tl], Bef),
     Int0 = clear_dead(Bef, Le#l.i, Vdb),
     Int1 = Int0#sr{reg=put_reg(R, Int0#sr.reg)},
     Ret = fetch_reg(R, Int1#sr.reg),
     {[{put_list,S1,S2,Ret}], Int1, St};
-set_cg([{var,R}], {binary,Segs}, Le, Vdb, Bef, #cg{bfail=Bfail}=St) ->
+put_cg([#k_var{name=R}], #k_binary{segs=Segs}, Le, Vdb, Bef,
+       #cg{bfail=Bfail}=St) ->
     %% At run-time, binaries are constructed in three stages:
     %% 1) First the size of the binary is calculated.
     %% 2) Then the binary is allocated.
@@ -1577,7 +2048,9 @@ set_cg([{var,R}], {binary,Segs}, Le, Vdb, Bef, #cg{bfail=Bfail}=St) ->
     {Sis++Code,Aft,St};
 
 %% Map: single variable key.
-set_cg([{var,R}], {map,Op,Map,[{map_pair,{var,_}=K,V}]}, Le, Vdb, Bef, St0) ->
+put_cg([#k_var{name=R}], #k_map{op=Op,var=Map,
+                                es=[#k_map_pair{key=#k_var{}=K,val=V}]},
+       Le, Vdb, Bef, St0) ->
     {Sis,Int0} = maybe_adjust_stack(Bef, Le#l.i, Le#l.i+1, Vdb, St0),
 
     SrcReg = cg_reg_arg_prefer_y(Map, Int0),
@@ -1592,22 +2065,23 @@ set_cg([{var,R}], {map,Op,Map,[{map_pair,{var,_}=K,V}]}, Le, Vdb, Bef, St0) ->
     Aft = Aft0#sr{reg=put_reg(R, Aft0#sr.reg)},
     Target = fetch_reg(R, Aft#sr.reg),
 
-    {Is,St1} = set_cg_map(Line, Op, SrcReg, Target, Live, List, St0),
+    {Is,St1} = put_cg_map(Line, Op, SrcReg, Target, Live, List, St0),
     {Sis++Is,Aft,St1};
 
 %% Map: (possibly) multiple literal keys.
-set_cg([{var,R}], {map,Op,Map,Es}, Le, Vdb, Bef, St0) ->
+put_cg([#k_var{name=R}], #k_map{op=Op,var=Map,es=Es}, Le, Vdb, Bef, St0) ->
 
     %% assert key literals
-    [] = [Var||{map_pair,{var,_}=Var,_} <- Es],
+    [] = [Var || #k_map_pair{key=#k_var{}=Var} <- Es],
 
     {Sis,Int0} = maybe_adjust_stack(Bef, Le#l.i, Le#l.i+1, Vdb, St0),
     SrcReg = cg_reg_arg_prefer_y(Map, Int0),
     Line = line(Le#l.a),
 
     %% fetch registers for values to be put into the map
-    Pairs = [{K,V} || {_,K,V} <- Es],
-    List = flatmap(fun({K,V}) -> [K,cg_reg_arg(V,Int0)] end, Pairs),
+    List = flatmap(fun(#k_map_pair{key=K,val=V}) ->
+                           [atomic(K),cg_reg_arg(V, Int0)]
+                   end, Es),
 
     Live = max_reg(Bef#sr.reg),
 
@@ -1616,16 +2090,16 @@ set_cg([{var,R}], {map,Op,Map,Es}, Le, Vdb, Bef, St0) ->
     Aft = Aft0#sr{reg=put_reg(R, Aft0#sr.reg)},
     Target = fetch_reg(R, Aft#sr.reg),
 
-    {Is,St1} = set_cg_map(Line, Op, SrcReg, Target, Live, List, St0),
+    {Is,St1} = put_cg_map(Line, Op, SrcReg, Target, Live, List, St0),
     {Sis++Is,Aft,St1};
 
 %% Everything else.
-set_cg([{var,R}], Con, Le, Vdb, Bef, St) ->
+put_cg([#k_var{name=R}], Con, Le, Vdb, Bef, St) ->
     %% Find a place for the return register first.
     Int = Bef#sr{reg=put_reg(R, Bef#sr.reg)},
     Ret = fetch_reg(R, Int#sr.reg),
     Ais = case Con of
-	      {tuple,Es} ->
+	      #k_tuple{es=Es} ->
 		  [{put_tuple,length(Es),Ret}] ++ cg_build_args(Es, Bef);
 	      Other ->
 		  [{move,cg_reg_arg(Other, Int),Ret}]
@@ -1633,7 +2107,7 @@ set_cg([{var,R}], Con, Le, Vdb, Bef, St) ->
     {Ais,clear_dead(Int, Le#l.i, Vdb),St}.
 
 
-set_cg_map(Line, Op0, SrcReg, Target, Live, List, St0) ->
+put_cg_map(Line, Op0, SrcReg, Target, Live, List, St0) ->
     Bfail = St0#cg.bfail,
     Fail = {f,St0#cg.bfail},
     Op = case Op0 of
@@ -1811,24 +2285,44 @@ cg_gen_binsize([], _, _, _, _, Acc) -> Acc.
 %% cg_bin_opt(Code0) -> Code
 %%  Optimize the size calculations for binary construction.
 
-cg_bin_opt([{move,Size,D},{bs_append,Fail,D,Extra,Regs,U,Bin,Flags,D}|Is]) ->
-    cg_bin_opt([{bs_append,Fail,Size,Extra,Regs,U,Bin,Flags,D}|Is]);
-cg_bin_opt([{move,Size,D},{bs_private_append,Fail,D,U,Bin,Flags,D}|Is]) ->
-    cg_bin_opt([{bs_private_append,Fail,Size,U,Bin,Flags,D}|Is]);
-cg_bin_opt([{move,{integer,0},D},{bs_add,_,[D,{integer,_}=S,1],Dst}|Is]) ->
-    cg_bin_opt([{move,S,Dst}|Is]);
-cg_bin_opt([{move,{integer,0},D},{bs_add,Fail,[D,S,U],Dst}|Is]) ->
-    cg_bin_opt([{bs_add,Fail,[{integer,0},S,U],Dst}|Is]);
-cg_bin_opt([{move,{integer,Bytes},D},{Op,Fail,D,Extra,Regs,Flags,D}|Is])
+cg_bin_opt([{move,S1,{x,X}=D},{gc_bif,Op,Fail,Live0,As,Dst}|Is]) ->
+    Live = if
+               X + 1 =:= Live0 -> X;
+               true -> Live0
+           end,
+    [{gc_bif,Op,Fail,Live,As,D}|cg_bin_opt([{move,S1,Dst}|Is])];
+cg_bin_opt([{move,_,_}=I1,{Op,_,_,_}=I2|Is])
+  when Op =:= bs_utf8_size orelse Op =:= bs_utf16_size ->
+    [I2|cg_bin_opt([I1|Is])];
+cg_bin_opt([{bs_add,_,[{integer,0},Src,1],Dst}|Is]) ->
+    cg_bin_opt_1([{move,Src,Dst}|Is]);
+cg_bin_opt([{bs_add,_,[Src,{integer,0},_],Dst}|Is]) ->
+    cg_bin_opt_1([{move,Src,Dst}|Is]);
+cg_bin_opt(Is) ->
+    cg_bin_opt_1(Is).
+
+cg_bin_opt_1([{move,Size,D},{bs_append,Fail,D,Extra,Regs,U,Bin,Flags,D}|Is]) ->
+    [{bs_append,Fail,Size,Extra,Regs,U,Bin,Flags,D}|cg_bin_opt(Is)];
+cg_bin_opt_1([{move,Size,D},{bs_private_append,Fail,D,U,Bin,Flags,D}|Is]) ->
+    [{bs_private_append,Fail,Size,U,Bin,Flags,D}|cg_bin_opt(Is)];
+cg_bin_opt_1([{move,Size,D},{Op,Fail,D,Extra,Regs,Flags,D}|Is])
   when Op =:= bs_init2; Op =:= bs_init_bits ->
-    cg_bin_opt([{Op,Fail,Bytes,Extra,Regs,Flags,D}|Is]);
-cg_bin_opt([{move,Src1,Dst},{bs_add,Fail,[Dst,Src2,U],Dst}|Is]) ->
-    cg_bin_opt([{bs_add,Fail,[Src1,Src2,U],Dst}|Is]);
-cg_bin_opt([I|Is]) ->
+    Bytes = case Size of
+                {integer,Int} -> Int;
+                _ -> Size
+            end,
+    [{Op,Fail,Bytes,Extra,Regs,Flags,D}|cg_bin_opt(Is)];
+cg_bin_opt_1([{move,S1,D},{bs_add,Fail,[D,S2,U],Dst}|Is]) ->
+    cg_bin_opt([{bs_add,Fail,[S1,S2,U],Dst}|Is]);
+cg_bin_opt_1([{move,S1,D},{bs_add,Fail,[S2,D,U],Dst}|Is]) ->
+    cg_bin_opt([{bs_add,Fail,[S2,S1,U],Dst}|Is]);
+cg_bin_opt_1([I|Is]) ->
     [I|cg_bin_opt(Is)];
-cg_bin_opt([]) -> [].
+cg_bin_opt_1([]) ->
+    [].
 
-cg_bin_put({bin_seg,[],S0,U,T,Fs,[E0,Next]}, Fail, Bef) ->
+cg_bin_put(#k_bin_seg{size=S0,unit=U,type=T,flags=Fs,seg=E0,next=Next},
+           Fail, Bef) ->
     S1 = cg_reg_arg(S0, Bef),
     E1 = cg_reg_arg(E0, Bef),
     {Format,Op} = case T of
@@ -1845,7 +2339,7 @@ cg_bin_put({bin_seg,[],S0,U,T,Fs,[E0,Next]}, Fail, Bef) ->
 	utf ->
 	    [{Op,Fail,{field_flags,Fs},E1}|cg_bin_put(Next, Fail, Bef)]
     end;
-cg_bin_put({bin_end,[]}, _, _) -> [].
+cg_bin_put(#k_bin_end{}, _, _) -> [].
 
 cg_build_args(As, Bef) ->
     [{put,cg_reg_arg(A, Bef)} || A <- As].
@@ -1865,13 +2359,12 @@ break_cg(Bs, Le, Vdb, Bef, St) ->
     {Ms ++ [{jump,{f,St#cg.break}}],
      Int#sr{reg=clear_regs(Int#sr.reg)},St}.
 
-guard_break_cg(Bs, Locked, #l{i=I}, Vdb, #sr{reg=Reg0}=Bef, St) ->
-    RegLocked = get_locked_regs(Reg0, Locked),
-    #sr{reg=Reg1} = Int = clear_dead(Bef#sr{reg=RegLocked}, I, Vdb),
+guard_break_cg(Bs, #l{i=I}, Vdb, #sr{reg=Reg0}=Bef, St) ->
+    #sr{reg=Reg1} = Int = clear_dead(Bef, I, Vdb),
     Reg2 = trim_free(Reg1),
     NumLocked = length(Reg2),
     Moves0 = gen_moves(Bs, Bef, NumLocked, []),
-    Moves = order_moves(Moves0, find_scratch_reg(RegLocked)),
+    Moves = order_moves(Moves0, find_scratch_reg(Reg0)),
     {BreakVars,_} = mapfoldl(fun(_, RegNum) ->
 				     {{RegNum,gbreakvar},RegNum+1}
 			     end, length(Reg2), Bs),
@@ -1879,31 +2372,17 @@ guard_break_cg(Bs, Locked, #l{i=I}, Vdb, #sr{reg=Reg0}=Bef, St) ->
     Aft = Int#sr{reg=Reg},
     {Moves ++ [{jump,{f,St#cg.break}}],Aft,St}.
 
-get_locked_regs([R|Rs0], Preserve) ->
-    case {get_locked_regs(Rs0, Preserve),R} of
-	{[],{_,V}} ->
-	    case lists:member(V, Preserve) of
-		true -> [R];
-		false -> []
-	    end;
-	{[],_} ->
-	    [];
-	{Rs,_} ->
-	    [R|Rs]
-    end;
-get_locked_regs([], _) -> [].
-
 %% cg_reg_arg(Arg0, Info) -> Arg
 %% cg_reg_args([Arg0], Info) -> [Arg]
 %%  Convert argument[s] into registers. Literal values are returned unchanged.
 
 cg_reg_args(As, Bef) -> [cg_reg_arg(A, Bef) || A <- As].
 
-cg_reg_arg({var,V}, Bef) -> fetch_var(V, Bef);
-cg_reg_arg(Literal, _) -> Literal.
+cg_reg_arg(#k_var{name=V}, Bef) -> fetch_var(V, Bef);
+cg_reg_arg(Literal, _) -> atomic(Literal).
 
-cg_reg_arg_prefer_y({var,V}, Bef) -> fetch_var_prefer_y(V, Bef);
-cg_reg_arg_prefer_y(Literal, _) -> Literal.
+cg_reg_arg_prefer_y(#k_var{name=V}, Bef) -> fetch_var_prefer_y(V, Bef);
+cg_reg_arg_prefer_y(Literal, _) -> atomic(Literal).
 
 %% cg_setup_call([Arg], Bef, Cur, Vdb) -> {[Instr],Aft}.
 %%  Do the complete setup for a call/enter.
@@ -1941,9 +2420,9 @@ cg_call_args(As, Bef, I, Vdb) ->
 
 load_arg_regs(Regs, As) -> load_arg_regs(Regs, As, 0).
 
-load_arg_regs([_|Rs], [{var,V}|As], I) -> [{I,V}|load_arg_regs(Rs, As, I+1)];
+load_arg_regs([_|Rs], [#k_var{name=V}|As], I) -> [{I,V}|load_arg_regs(Rs, As, I+1)];
 load_arg_regs([_|Rs], [A|As], I) -> [{I,A}|load_arg_regs(Rs, As, I+1)];
-load_arg_regs([], [{var,V}|As], I) -> [{I,V}|load_arg_regs([], As, I+1)];
+load_arg_regs([], [#k_var{name=V}|As], I) -> [{I,V}|load_arg_regs([], As, I+1)];
 load_arg_regs([], [A|As], I) -> [{I,A}|load_arg_regs([], As, I+1)];
 load_arg_regs(Rs, [], _) -> Rs.
 
@@ -1979,12 +2458,13 @@ move_unsaved([], _, Regs, Acc) -> {Acc,Regs}.
 
 gen_moves(As, Sr) -> gen_moves(As, Sr, 0, []).
 
-gen_moves([{var,V}|As], Sr, I, Acc) ->
+gen_moves([#k_var{name=V}|As], Sr, I, Acc) ->
     case fetch_var(V, Sr) of
 	{x,I} -> gen_moves(As, Sr, I+1, Acc);
 	Reg -> gen_moves(As, Sr, I+1, [{move,Reg,{x,I}}|Acc])
     end;
-gen_moves([A|As], Sr, I, Acc) ->
+gen_moves([A0|As], Sr, I, Acc) ->
+    A = atomic(A0),
     gen_moves(As, Sr, I+1, [{move,A,{x,I}}|Acc]);
 gen_moves([], _, _, Acc) -> lists:keysort(3, Acc).
 
@@ -2032,21 +2512,21 @@ break_up_cycle1(Dst, [M|Path], LastMove) ->
 %% clear_dead(Sr, Until, Vdb) -> Aft.
 %%  Remove all variables in Sr which have died AT ALL so far.
 
-clear_dead(Sr, Until, Vdb) ->
-    Sr#sr{reg=clear_dead_reg(Sr, Until, Vdb),
-	  stk=clear_dead_stk(Sr#sr.stk, Until, Vdb)}.
+clear_dead(#sr{stk=Stk}=Sr0, Until, Vdb) ->
+    Sr = Sr0#sr{reg=clear_dead_reg(Sr0, Until, Vdb),
+                stk=clear_dead_stk(Stk, Until, Vdb)},
+    reserve(Sr).
 
 clear_dead_reg(Sr, Until, Vdb) ->
-    Reg = [case R of
-            {_I,V} = IV ->
-                case vdb_find(V, Vdb) of
-                    {V,_,L} when L > Until -> IV;
-                    _ -> free		%Remove anything else
-                end;
-            {reserved,_I,_V} = Reserved -> Reserved;
-            free -> free
-        end || R <- Sr#sr.reg],
-    reserve(Sr#sr.res, Reg, Sr#sr.stk).
+    [case R of
+         {_I,V} = IV ->
+             case vdb_find(V, Vdb) of
+                 {V,_,L} when L > Until -> IV;
+                 _ -> free                      %Remove anything else
+             end;
+         {reserved,_I,_V}=Reserved -> Reserved;
+         free -> free
+     end || R <- Sr#sr.reg].
 
 clear_dead_stk(Stk, Until, Vdb) ->
     [case S of
@@ -2118,16 +2598,25 @@ adjust_stack(Bef, Fb, Lf, Vdb) ->
 
 save_stack(Stk0, Fb, Lf, Vdb) ->
     %% New variables that are in use but not on stack.
-    New = [VFL || {V,F,L} = VFL <- Vdb,
-		  F < Fb,
-		  L >= Lf,
-		  not on_stack(V, Stk0)],
+    New = new_not_on_stack(Stk0, Fb, Lf, Vdb),
+
     %% Add new variables that are not just dropped immediately.
     %% N.B. foldr works backwards from the end!!
     Saves = [V || {V,_,_} <- keysort(3, New)],
     Stk1 = foldr(fun (V, Stk) -> put_stack(V, Stk) end, Stk0, Saves),
     {Stk1,Saves}.
 
+%% new_not_on_stack(Stack, FirstBefore, LastFrom, Vdb) ->
+%%                 [{Variable,First,Last}]
+%%  Return information about all variables that are used past current
+%%  point and that are not already on the stack.
+
+new_not_on_stack(Stk, Fb, Lf, Vdb) ->
+    [VFL || {V,F,L} = VFL <- Vdb,
+            F < Fb,
+            L >= Lf,
+            not on_stack(V, Stk)].
+
 %% saves([SaveVar], Reg, Stk) -> [{move,Reg,Stk}].
 %%  Generate move instructions to save variables onto stack.  The
 %%  stack/reg info used is that after the new stack has been made.
@@ -2153,7 +2642,7 @@ fetch_var_prefer_y(V, #sr{reg=Reg,stk=Stk}) ->
     end.
 
 load_vars(Vs, Regs) ->
-    foldl(fun ({var,V}, Rs) -> put_reg(V, Rs) end, Regs, Vs).
+    foldl(fun (#k_var{name=V}, Rs) -> put_reg(V, Rs) end, Regs, Vs).
 
 %% put_reg(Val, Regs) -> Regs.
 %% find_reg(Val, Regs) -> {ok,r{R}} | error.
@@ -2233,10 +2722,6 @@ find_stack(_, [], _) -> error.
 
 on_stack(V, Stk) -> keymember(V, 1, Stk).
 
-is_register({x,_}) -> true;
-is_register({yy,_}) -> true;
-is_register(_) -> false.
-
 %% put_catch(CatchTag, Stack) -> Stack'
 %% drop_catch(CatchTag, Stack) -> Stack'
 %%  Special interface for putting and removing catch tags, to ensure that
@@ -2254,6 +2739,16 @@ put_catch(Tag, [Other|Stk], Acc) ->
 drop_catch(Tag, [{{catch_tag,Tag}}|Stk]) -> [free|Stk];
 drop_catch(Tag, [Other|Stk]) -> [Other|drop_catch(Tag, Stk)].
 
+%% atomic(Klit) -> Lit.
+%% atomic_list([Klit]) -> [Lit].
+
+atomic(#k_literal{val=V}) -> {literal,V};
+atomic(#k_int{val=I}) -> {integer,I};
+atomic(#k_float{val=F}) -> {float,F};
+atomic(#k_atom{val=A}) -> {atom,A};
+%%atomic(#k_char{val=C}) -> {char,C};
+atomic(#k_nil{}) -> nil.
+
 %% new_label(St) -> {L,St}.
 
 new_label(#cg{lcount=Next}=St) ->
@@ -2296,3 +2791,86 @@ flatmapfoldl(F, Accu0, [Hd|Tail]) ->
     {Rs,Accu2} = flatmapfoldl(F, Accu1, Tail),
     {R++Rs,Accu2};
 flatmapfoldl(_, Accu, []) -> {[],Accu}.
+
+%% Keep track of life time for variables.
+%%
+%% init_vars([{var,VarName}]) -> Vdb.
+%% new_vars([VarName], I, Vdb) -> Vdb.
+%% use_vars([VarName], I, Vdb) -> Vdb.
+%% add_var(VarName, F, L, Vdb) -> Vdb.
+%%
+%% The list of variable names for new_vars/3 and use_vars/3
+%% must be sorted.
+
+init_vars(Vs) ->
+    vdb_new(Vs).
+
+new_vars([], _, Vdb) -> Vdb;
+new_vars([V], I, Vdb) -> vdb_store_new(V, {V,I,I}, Vdb);
+new_vars(Vs, I, Vdb) -> vdb_update_vars(Vs, Vdb, I).
+
+use_vars([], _, Vdb) ->
+    Vdb;
+use_vars([V], I, Vdb) ->
+    case vdb_find(V, Vdb) of
+        {V,F,L} when I > L -> vdb_update(V, {V,F,I}, Vdb);
+        {V,_,_} -> Vdb;
+        error -> vdb_store_new(V, {V,I,I}, Vdb)
+    end;
+use_vars(Vs, I, Vdb) -> vdb_update_vars(Vs, Vdb, I).
+
+add_var(V, F, L, Vdb) ->
+    vdb_store_new(V, {V,F,L}, Vdb).
+
+%% vdb
+
+vdb_new(Vs) ->
+    ordsets:from_list([{V,0,0} || #k_var{name=V} <- Vs]).
+
+-type var() :: atom().
+
+-spec vdb_find(var(), [vdb_entry()]) -> 'error' | vdb_entry().
+
+vdb_find(V, Vdb) ->
+    case lists:keyfind(V, 1, Vdb) of
+        false -> error;
+        Vd -> Vd
+    end.
+
+vdb_update(V, Update, [{V,_,_}|Vdb]) ->
+    [Update|Vdb];
+vdb_update(V, Update, [Vd|Vdb]) ->
+    [Vd|vdb_update(V, Update, Vdb)].
+
+vdb_store_new(V, New, [{V1,_,_}=Vd|Vdb]) when V > V1 ->
+    [Vd|vdb_store_new(V, New, Vdb)];
+vdb_store_new(V, New, [{V1,_,_}|_]=Vdb) when V < V1 ->
+    [New|Vdb];
+vdb_store_new(_, New, []) -> [New].
+
+vdb_update_vars([V|_]=Vs, [{V1,_,_}=Vd|Vdb], I) when V > V1 ->
+    [Vd|vdb_update_vars(Vs, Vdb, I)];
+vdb_update_vars([V|Vs], [{V1,_,_}|_]=Vdb, I) when V < V1 ->
+    %% New variable.
+    [{V,I,I}|vdb_update_vars(Vs, Vdb, I)];
+vdb_update_vars([V|Vs], [{_,F,L}=Vd|Vdb], I) ->
+    %% Existing variable.
+    if
+        I > L -> [{V,F,I}|vdb_update_vars(Vs, Vdb, I)];
+        true ->  [Vd|vdb_update_vars(Vs, Vdb, I)]
+    end;
+vdb_update_vars([V|Vs], [], I) ->
+    %% New variable.
+    [{V,I,I}|vdb_update_vars(Vs, [], I)];
+vdb_update_vars([], Vdb, _) -> Vdb.
+
+%% vdb_sub(Min, Max, Vdb) -> Vdb.
+%%  Extract variables which are used before and after Min.  Lock
+%%  variables alive after Max.
+
+vdb_sub(Min, Max, Vdb) ->
+    [ if L >= Max -> {V,F,locked};
+         true -> Vd
+      end || {V,F,L}=Vd <- Vdb,
+             F < Min,
+             L >= Min ].
diff --git a/lib/compiler/src/v3_core.erl b/lib/compiler/src/v3_core.erl
index ae650546e5..6029b91cdc 100644
--- a/lib/compiler/src/v3_core.erl
+++ b/lib/compiler/src/v3_core.erl
@@ -920,8 +920,9 @@ try_exception(Ecs0, St0) ->
     %% Note that Tag is not needed for rethrow - it is already in Info.
     {Evs,St1} = new_vars(3, St0), % Tag, Value, Info
     {Ecs1,Ceps,St2} = clauses(Ecs0, St1),
+    Ecs2 = try_build_stacktrace(Ecs1, hd(Evs)),
     [_,Value,Info] = Evs,
-    LA = case Ecs1 of
+    LA = case Ecs2 of
 	     [] -> [];
 	     [C|_] -> get_lineno_anno(C)
 	 end,
@@ -930,7 +931,7 @@ try_exception(Ecs0, St0) ->
 		  body=[#iprimop{anno=#a{},       %Must have an #a{}
 				 name=#c_literal{val=raise},
 				 args=[Info,Value]}]},
-    Hs = [#icase{anno=#a{anno=LA},args=[c_tuple(Evs)],clauses=Ecs1,fc=Ec}],
+    Hs = [#icase{anno=#a{anno=LA},args=[c_tuple(Evs)],clauses=Ecs2,fc=Ec}],
     {Evs,Ceps++Hs,St2}.
 
 try_after(As, St0) ->
@@ -946,6 +947,25 @@ try_after(As, St0) ->
     Hs = [#icase{anno=#a{},args=[c_tuple(Evs)],clauses=[],fc=Ec}],
     {Evs,Hs,St1}.
 
+try_build_stacktrace([#iclause{pats=Ps0,body=B0}=C0|Cs], RawStk) ->
+    [#c_tuple{es=[Class,Exc,Stk]}=Tup] = Ps0,
+    case Stk of
+        #c_var{name='_'} ->
+            %% Stacktrace variable is not used. Nothing to do.
+            [C0|try_build_stacktrace(Cs, RawStk)];
+        _ ->
+            %% Add code to build the stacktrace.
+            Ps = [Tup#c_tuple{es=[Class,Exc,RawStk]}],
+            Call = #iprimop{anno=#a{},
+                            name=#c_literal{val=build_stacktrace},
+                            args=[RawStk]},
+            Iset = #iset{var=Stk,arg=Call},
+            B = [Iset|B0],
+            C = C0#iclause{pats=Ps,body=B},
+            [C|try_build_stacktrace(Cs, RawStk)]
+    end;
+try_build_stacktrace([], _) -> [].
+
 %% expr_bin([ArgExpr], St) -> {[Arg],[PreExpr],St}.
 %%  Flatten the arguments of a bin. Do this straight left to right!
 %%  Note that ibinary needs to have its annotation wrapped in a #a{}
@@ -2462,9 +2482,11 @@ cexpr(#icase{anno=A,args=Largs,clauses=Lcs,fc=Lfc}, As, St0) ->
 cexpr(#ireceive1{anno=A,clauses=Lcs}, As, St0) ->
     Exp = intersection(A#a.ns, As),		%Exports
     {Ccs,St1} = cclauses(Lcs, Exp, St0),
+    True = #c_literal{val=true},
+    Action = core_lib:make_values(lists:duplicate(1+length(Exp), True)),
     {#c_receive{anno=A#a.anno,
 		clauses=Ccs,
-		timeout=#c_literal{val=infinity},action=#c_literal{val=true}},
+		timeout=#c_literal{val=infinity},action=Action},
      Exp,A#a.us,St1};
 cexpr(#ireceive2{anno=A,clauses=Lcs,timeout=Lto,action=Les}, As, St0) ->
     Exp = intersection(A#a.ns, As),		%Exports
@@ -2505,8 +2527,46 @@ cexpr(#ifun{anno=#a{us=Us0}=A0,name={named,Name},fc=#iclause{pats=Ps}}=Fun0,
     end;
 cexpr(#iapply{anno=A,op=Op,args=Args}, _As, St) ->
     {#c_apply{anno=A#a.anno,op=Op,args=Args},[],A#a.us,St};
-cexpr(#icall{anno=A,module=Mod,name=Name,args=Args}, _As, St) ->
-    {#c_call{anno=A#a.anno,module=Mod,name=Name,args=Args},[],A#a.us,St};
+cexpr(#icall{anno=A,module=Mod,name=Name,args=Args}, _As, St0) ->
+    Anno = A#a.anno,
+    case (not cerl:is_c_atom(Mod)) andalso member(tuple_calls, St0#core.opts) of
+	true ->
+	    GenAnno = [compiler_generated|Anno],
+
+	    %% Generate the clause that matches on the tuple
+	    {TupleVar,St1} = new_var(GenAnno, St0),
+	    {TupleSizeVar, St2} = new_var(GenAnno, St1),
+	    {TupleModVar, St3} = new_var(GenAnno, St2),
+	    {TupleArgsVar, St4} = new_var(GenAnno, St3),
+	    TryVar = cerl:c_var('Try'),
+
+	    TupleGuardExpr =
+		cerl:c_let([TupleSizeVar],
+			   c_call_erl(tuple_size, [TupleVar]),
+			   c_call_erl('>', [TupleSizeVar, cerl:c_int(0)])),
+
+	    TupleGuard =
+		cerl:c_try(TupleGuardExpr, [TryVar], TryVar,
+			   [cerl:c_var('T'),cerl:c_var('R')], cerl:c_atom(false)),
+
+	    TupleApply =
+		cerl:c_let([TupleModVar],
+			   c_call_erl(element, [cerl:c_int(1),TupleVar]),
+			   cerl:c_let([TupleArgsVar],
+				      cerl:make_list(Args ++ [TupleVar]),
+				      c_call_erl(apply, [TupleModVar,Name,TupleArgsVar]))),
+
+	    TupleClause = cerl:ann_c_clause(GenAnno, [TupleVar], TupleGuard, TupleApply),
+
+	    %% Generate the fallback clause
+	    {OtherVar,St5} = new_var(GenAnno, St4),
+	    OtherApply = cerl:ann_c_call(GenAnno, OtherVar, Name, Args),
+	    OtherClause = cerl:ann_c_clause(GenAnno, [OtherVar], OtherApply),
+
+	    {cerl:ann_c_case(GenAnno, Mod, [TupleClause,OtherClause]),[],A#a.us,St5};
+	false ->
+	    {#c_call{anno=Anno,module=Mod,name=Name,args=Args},[],A#a.us,St0}
+    end;
 cexpr(#iprimop{anno=A,name=Name,args=Args}, _As, St) ->
     {#c_primop{anno=A#a.anno,name=Name,args=Args},[],A#a.us,St};
 cexpr(#iprotect{anno=A,body=Es}, _As, St0) ->
@@ -2536,6 +2596,9 @@ cfun(#ifun{anno=A,id=Id,vars=Args,clauses=Lcs,fc=Lfc}, _As, St0) ->
                          clauses=Ccs ++ [Cfc]}},
      [],A#a.us,St2}.
 
+c_call_erl(Fun, Args) ->
+    cerl:c_call(cerl:c_atom(erlang), cerl:c_atom(Fun), Args).
+
 %% lit_vars(Literal) -> [Var].
 
 lit_vars(Lit) -> lit_vars(Lit, []).
diff --git a/lib/compiler/src/v3_kernel.erl b/lib/compiler/src/v3_kernel.erl
index 1fc05109c5..fd73e5a7dc 100644
--- a/lib/compiler/src/v3_kernel.erl
+++ b/lib/compiler/src/v3_kernel.erl
@@ -82,7 +82,8 @@
 -export([module/2,format_error/1]).
 
 -import(lists, [map/2,foldl/3,foldr/3,mapfoldl/3,splitwith/2,member/2,
-		keymember/3,keyfind/3,partition/2,droplast/1,last/1,sort/1]).
+		keymember/3,keyfind/3,partition/2,droplast/1,last/1,sort/1,
+                reverse/1]).
 -import(ordsets, [add_element/2,del_element/2,union/2,union/1,subtract/2]).
 -import(cerl, [c_tuple/1]).
 
@@ -107,6 +108,7 @@ copy_anno(Kdst, Ksrc) ->
 -record(iclause, {anno=[],isub,osub,pats,guard,body}).
 -record(ireceive_accept, {anno=[],arg}).
 -record(ireceive_next, {anno=[],arg}).
+-record(ignored, {anno=[]}).
 
 -type warning() :: term().	% XXX: REFINE
 
@@ -159,11 +161,9 @@ function({#c_var{name={F,Arity}=FA},Body}, St0) ->
 	{#ifun{anno=Ab,vars=Kvs,body=B0},[],St2} = expr(Body, new_sub(), St1),
 	{B1,_,St3} = ubody(B0, return, St2),
 	%%B1 = B0, St3 = St2,				%Null second pass
-	{#k_fdef{anno=#k{us=[],ns=[],a=Ab},
-		 func=F,arity=Arity,vars=Kvs,body=B1},St3}
+        {make_fdef(#k{us=[],ns=[],a=Ab}, F, Arity, Kvs, B1),St3}
     catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
+        Class:Error:Stack ->
 	    io:fwrite("Function: ~w/~w\n", [F,Arity]),
 	    erlang:raise(Class, Error, Stack)
     end.
@@ -489,7 +489,7 @@ make_alt(First0, Then0) ->
     Then1 = pre_seq(droplast(Then0), last(Then0)),
     First2 = make_protected(First1),
     Then2 = make_protected(Then1),
-    Body = #k_atom{val=ignored},
+    Body = #ignored{},
     First3 = #k_guard_clause{guard=First2,body=Body},
     Then3 = #k_guard_clause{guard=Then2,body=Body},
     First = #k_guard{clauses=[First3]},
@@ -1589,23 +1589,18 @@ match_var([U|Us], Cs0, Def, St) ->
 %%  according to type, the order is really irrelevant but tries to be
 %%  smart.
 
-match_con(Us, [C], Def, St) ->
-    %% There is only one clause. We can keep literal tuples and
-    %% lists, but we must convert []/integer/float/atom literals
-    %% to the proper record (#k_nil{} and so on).
-    Cs = [expand_pat_lit_clause(C, false)],
-    match_con_1(Us, Cs, Def, St);
 match_con(Us, Cs0, Def, St) ->
-    %% More than one clause. Remove literals at the top level.
-    Cs = [expand_pat_lit_clause(C, true) || C <- Cs0],
+    %% Expand literals at the top level.
+    Cs = [expand_pat_lit_clause(C) || C <- Cs0],
     match_con_1(Us, Cs, Def, St).
 
 match_con_1([U|_Us] = L, Cs, Def, St0) ->
     %% Extract clauses for different constructors (types).
     %%ok = io:format("match_con ~p~n", [Cs]),
-    Ttcs = select_types([k_binary], Cs) ++ select_bin_con(Cs) ++
-	select_types([k_cons,k_tuple,k_map,k_atom,k_float,k_int,
-		      k_nil,k_literal], Cs),
+    Ttcs0 = select_types([k_binary], Cs) ++ select_bin_con(Cs) ++
+        select_types([k_cons,k_tuple,k_map,k_atom,k_float,
+                      k_int,k_nil], Cs),
+    Ttcs = opt_single_valued(Ttcs0),
     %%ok = io:format("ttcs = ~p~n", [Ttcs]),
     {Scs,St1} =
 	mapfoldl(fun ({T,Tcs}, St) ->
@@ -1618,28 +1613,14 @@ match_con_1([U|_Us] = L, Cs, Def, St0) ->
 
 select_types(Types, Cs) ->
     [{T,Tcs} || T <- Types, begin Tcs = select(T, Cs), Tcs =/= [] end].
-    
-expand_pat_lit_clause(#iclause{pats=[#ialias{pat=#k_literal{anno=A,val=Val}}=Alias|Ps]}=C, B) ->
-    P = case B of
-	    true -> expand_pat_lit(Val, A);
-	    false -> literal(Val, A)
-	end,
+
+expand_pat_lit_clause(#iclause{pats=[#ialias{pat=#k_literal{anno=A,val=Val}}=Alias|Ps]}=C) ->
+    P = expand_pat_lit(Val, A),
     C#iclause{pats=[Alias#ialias{pat=P}|Ps]};
-expand_pat_lit_clause(#iclause{pats=[#k_literal{anno=A,val=Val}|Ps]}=C, B) ->
-    P = case B of
-	    true -> expand_pat_lit(Val, A);
-	    false -> literal(Val, A)
-	end,
+expand_pat_lit_clause(#iclause{pats=[#k_literal{anno=A,val=Val}|Ps]}=C) ->
+    P = expand_pat_lit(Val, A),
     C#iclause{pats=[P|Ps]};
-expand_pat_lit_clause(#iclause{pats=[#k_binary{anno=A,segs=#k_bin_end{}}|Ps]}=C, B) ->
-    case B of
-	true ->
-	    C;
-	false ->
-	    P = #k_literal{anno=A,val = <<>>},
-	    C#iclause{pats=[P|Ps]}
-    end;
-expand_pat_lit_clause(C, _) -> C.
+expand_pat_lit_clause(C) -> C.
 
 expand_pat_lit([H|T], A) ->
     #k_cons{anno=A,hd=literal(H, A),tl=literal(T, A)};
@@ -1659,6 +1640,107 @@ literal(Val, A) when is_atom(Val) ->
 literal(Val, A) when is_list(Val); is_tuple(Val) ->
     #k_literal{anno=A,val=Val}.
 
+%% opt_singled_valued([{Type,Clauses}]) -> [{Type,Clauses}].
+%%  If a type only has one clause and if the pattern is literal,
+%%  the matching can be done more efficiently by directly comparing
+%%  with the literal (that is especially true for binaries).
+
+opt_single_valued(Ttcs) ->
+    opt_single_valued(Ttcs, [], []).
+
+opt_single_valued([{_,[#iclause{pats=[P0|Ps]}=Tc]}=Ttc|Ttcs], TtcAcc, LitAcc) ->
+    try combine_lit_pat(P0) of
+        P ->
+            LitTtc = Tc#iclause{pats=[P|Ps]},
+            opt_single_valued(Ttcs, TtcAcc, [LitTtc|LitAcc])
+    catch
+        not_possible ->
+            opt_single_valued(Ttcs, [Ttc|TtcAcc], LitAcc)
+    end;
+opt_single_valued([Ttc|Ttcs], TtcAcc, LitAcc) ->
+    opt_single_valued(Ttcs, [Ttc|TtcAcc], LitAcc);
+opt_single_valued([], TtcAcc, []) ->
+    reverse(TtcAcc);
+opt_single_valued([], TtcAcc, LitAcc) ->
+    Literals = {k_literal,reverse(LitAcc)},
+    %% Test the literals as early as possible.
+    case reverse(TtcAcc) of
+        [{k_binary,_}=Bin|Ttcs] ->
+            %% The delayed creation of sub binaries requires
+            %% bs_start_match2 to be the first instruction in the
+            %% function.
+            [Bin,Literals|Ttcs];
+        Ttcs ->
+            [Literals|Ttcs]
+    end.
+
+combine_lit_pat(#ialias{pat=Pat0}=Alias) ->
+    Pat = combine_lit_pat(Pat0),
+    Alias#ialias{pat=Pat};
+combine_lit_pat(Pat) ->
+    case do_combine_lit_pat(Pat) of
+        #k_literal{val=Val} when is_atom(Val) ->
+            throw(not_possible);
+        #k_literal{val=Val} when is_number(Val) ->
+            throw(not_possible);
+        #k_literal{val=[]} ->
+            throw(not_possible);
+        #k_literal{}=Lit ->
+            Lit
+    end.
+
+do_combine_lit_pat(#k_atom{anno=A,val=Val}) ->
+    #k_literal{anno=A,val=Val};
+do_combine_lit_pat(#k_float{anno=A,val=Val}) ->
+    #k_literal{anno=A,val=Val};
+do_combine_lit_pat(#k_int{anno=A,val=Val}) ->
+    #k_literal{anno=A,val=Val};
+do_combine_lit_pat(#k_nil{anno=A}) ->
+    #k_literal{anno=A,val=[]};
+do_combine_lit_pat(#k_binary{anno=A,segs=Segs}) ->
+    Bin = combine_bin_segs(Segs),
+    #k_literal{anno=A,val=Bin};
+do_combine_lit_pat(#k_cons{anno=A,hd=Hd0,tl=Tl0}) ->
+    #k_literal{val=Hd} = do_combine_lit_pat(Hd0),
+    #k_literal{val=Tl} = do_combine_lit_pat(Tl0),
+    #k_literal{anno=A,val=[Hd|Tl]};
+do_combine_lit_pat(#k_literal{}=Lit) ->
+    Lit;
+do_combine_lit_pat(#k_tuple{anno=A,es=Es0}) ->
+    Es = [begin
+              #k_literal{val=Lit} = do_combine_lit_pat(El),
+              Lit
+          end || El <- Es0],
+    #k_literal{anno=A,val=list_to_tuple(Es)};
+do_combine_lit_pat(_) ->
+    throw(not_possible).
+
+combine_bin_segs(#k_bin_seg{size=Size0,unit=Unit,type=integer,
+                            flags=[unsigned,big],seg=Seg,next=Next}) ->
+    #k_literal{val=Size1} = do_combine_lit_pat(Size0),
+    #k_literal{val=Int} = do_combine_lit_pat(Seg),
+    Size = Size1 * Unit,
+    if
+        0 < Size, Size < 64 ->
+            Bin = <<Int:Size>>,
+            case Bin of
+                <<Int:Size>> ->
+                    NextBin = combine_bin_segs(Next),
+                    <<Bin/bits,NextBin/bits>>;
+                _ ->
+                    %% The integer Int does not fit in the segment,
+                    %% thus it will not match.
+                    throw(not_possible)
+            end;
+        true ->
+            %% Avoid creating huge binary literals.
+            throw(not_possible)
+    end;
+combine_bin_segs(#k_bin_end{}) ->
+    <<>>;
+combine_bin_segs(_) ->
+    throw(not_possible).
+
 %% select_bin_con([Clause]) -> [{Type,[Clause]}].
 %%  Extract clauses for the k_bin_seg constructor.  As k_bin_seg
 %%  matching can overlap, the k_bin_seg constructors cannot be
@@ -2143,7 +2225,9 @@ ubody(E, return, St0) ->
 	    {Ea,Pa,St1} = force_atomic(E, St0),
 	    ubody(pre_seq(Pa, #ivalues{args=[Ea]}), return, St1)
     end;
-ubody(E, {break,_Rs} = Break, St0) ->
+ubody(#ignored{}, {break,_} = Break, St) ->
+    ubody(#ivalues{args=[]}, Break, St);
+ubody(E, {break,[_]} = Break, St0) ->
     %%ok = io:fwrite("ubody ~w:~p~n", [?LINE,{E,Br}]),
     %% Exiting expressions need no trailing break.
     case is_exit_expr(E) of
@@ -2151,6 +2235,16 @@ ubody(E, {break,_Rs} = Break, St0) ->
 	false ->
 	    {Ea,Pa,St1} = force_atomic(E, St0),
 	    ubody(pre_seq(Pa, #ivalues{args=[Ea]}), Break, St1)
+    end;
+ubody(E, {break,Rs}=Break, St0) ->
+    case is_exit_expr(E) of
+        true ->
+            uexpr(E, return, St0);
+        false ->
+            {Vs,St1} = new_vars(length(Rs), St0),
+            Iset = #iset{vars=Vs,arg=E},
+            PreSeq = pre_seq([Iset], #ivalues{args=Vs}),
+            ubody(PreSeq, Break, St1)
     end.
 
 iletrec_funs(#iletrec{defs=Fs}, St0) ->
@@ -2179,9 +2273,8 @@ iletrec_funs_gen(Fs, FreeVs, St) ->
 		  Arity0 = length(Vs),
 		  {Fb1,_,Lst1} = ubody(Fb0, return, Lst0#kern{ff={N,Arity0}}),
 		  Arity = Arity0 + length(FreeVs),
-		  Fun = #k_fdef{anno=#k{us=[],ns=[],a=Fa},
-				func=N,arity=Arity,
-				vars=Vs ++ FreeVs,body=Fb1},
+                  Fun = make_fdef(#k{us=[],ns=[],a=Fa}, N, Arity,
+                                  Vs++FreeVs, Fb1),
 		  Lst1#kern{funs=[Fun|Lst1#kern.funs]}
 	  end, St, Fs).
 
@@ -2325,8 +2418,7 @@ uexpr(#ifun{anno=A,vars=Vs,body=B0}, {break,Rs}, St0) ->
 		%% No id annotation. Must invent a fun name.
 		new_fun_name(St1)
 	end,
-    Fun = #k_fdef{anno=#k{us=[],ns=[],a=A},func=Fname,arity=Arity,
-		  vars=Vs ++ Fvs,body=B1},
+    Fun = make_fdef(#k{us=[],ns=[],a=A}, Fname, Arity, Vs++Fvs, B1),
     {#k_bif{anno=#k{us=Free,ns=lit_list_vars(Rs),a=A},
 	    op=#k_internal{name=make_fun,arity=length(Free)+2},
 	    args=[#k_atom{val=Fname},#k_int{val=Arity}|Fvs],
@@ -2343,6 +2435,16 @@ uexpr(Lit, {break,Rs0}, St0) ->
 add_local_function(_, #kern{funs=ignore}=St) -> St;
 add_local_function(F, #kern{funs=Funs}=St) -> St#kern{funs=[F|Funs]}.
 
+%% Make a #k_fdef{}, making sure that the body is always a #k_match{}.
+make_fdef(Anno, Name, Arity, Vs, #k_match{}=Body) ->
+    #k_fdef{anno=Anno,func=Name,arity=Arity,vars=Vs,body=Body};
+make_fdef(Anno, Name, Arity, Vs, Body) ->
+    Ka = get_kanno(Body),
+    Match = #k_match{anno=#k{us=Ka#k.us,ns=[],a=Ka#k.a},
+                     vars=Vs,body=Body,ret=[]},
+    #k_fdef{anno=Anno,func=Name,arity=Arity,vars=Vs,body=Match}.
+
+
 %% handle_reuse_annos([#k_var{}], State) -> State.
 %%  In general, it is only safe to reuse a variable for a match context
 %%  if the original value of the variable will no longer be needed.
diff --git a/lib/compiler/src/v3_kernel_pp.erl b/lib/compiler/src/v3_kernel_pp.erl
index 53097d0d7d..ac91039ae0 100644
--- a/lib/compiler/src/v3_kernel_pp.erl
+++ b/lib/compiler/src/v3_kernel_pp.erl
@@ -491,7 +491,7 @@ indent(Ctxt) -> indent(Ctxt#ctxt.indent, Ctxt).
 indent(N, _Ctxt) when N =< 0 -> "";
 indent(N, Ctxt) ->
     T = Ctxt#ctxt.tab_width,
-    string:chars($\t, N div T, string:chars($\s, N rem T)).
+    lists:duplicate(N div T, $\t) ++ lists:duplicate(N rem T, $\s).
 
 nl_indent(Ctxt) -> [$\n|indent(Ctxt)].
 
@@ -508,7 +508,7 @@ unindent([$\t|T], N, Ctxt, C) ->
     if N >= Tab ->
 	    unindent(T, N - Tab, Ctxt, C);
        true ->
-	    unindent([string:chars($\s, Tab - N)|T], 0, Ctxt, C)
+            unindent([lists:duplicate(Tab - N, $\s)|T], 0, Ctxt, C)
     end;
 unindent([L|T], N, Ctxt, C) when is_list(L) ->
     unindent(L, N, Ctxt, [T|C]);
diff --git a/lib/compiler/src/v3_life.erl b/lib/compiler/src/v3_life.erl
deleted file mode 100644
index be3ade47ff..0000000000
--- a/lib/compiler/src/v3_life.erl
+++ /dev/null
@@ -1,468 +0,0 @@
-%%
-%% %CopyrightBegin%
-%%
-%% Copyright Ericsson AB 1999-2016. All Rights Reserved.
-%%
-%% Licensed under the Apache License, Version 2.0 (the "License");
-%% you may not use this file except in compliance with the License.
-%% You may obtain a copy of the License at
-%%
-%%     http://www.apache.org/licenses/LICENSE-2.0
-%%
-%% Unless required by applicable law or agreed to in writing, software
-%% distributed under the License is distributed on an "AS IS" BASIS,
-%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-%% See the License for the specific language governing permissions and
-%% limitations under the License.
-%%
-%% %CopyrightEnd%
-%%
-%% Purpose : Convert annotated kernel expressions to annotated beam format.
-
-%% This module creates beam format annotated with variable lifetime
-%% information.  Each thing is given an index and for each variable we
-%% store the first and last index for its occurrence.  The variable
-%% database, VDB, attached to each thing is only relevant internally
-%% for that thing.
-%%
-%% For nested things like matches the numbering continues locally and
-%% the VDB for that thing refers to the variable usage within that
-%% thing.  Variables which live through a such a thing are internally
-%% given a very large last index.  Internally the indexes continue
-%% after the index of that thing.  This creates no problems as the
-%% internal variable info never escapes and externally we only see
-%% variable which are alive both before or after.
-%%
-%% This means that variables never "escape" from a thing and the only
-%% way to get values from a thing is to "return" them, with 'break' or
-%% 'return'.  Externally these values become the return values of the
-%% thing.  This is no real limitation as most nested things have
-%% multiple threads so working out a common best variable usage is
-%% difficult.
-
--module(v3_life).
-
--export([module/2]).
-
--export([vdb_find/2]).
-
--import(lists, [member/2,map/2,reverse/1,sort/1]).
--import(ordsets, [add_element/2,intersection/2,union/2]).
-
--include("v3_kernel.hrl").
--include("v3_life.hrl").
-
--type fa() :: {atom(),arity()}.
-
-%% These are not defined in v3_kernel.hrl.
-get_kanno(Kthing) -> element(2, Kthing).
-%%set_kanno(Kthing, Anno) -> setelement(2, Kthing, Anno).
-
--spec module(#k_mdef{}, [compile:option()]) ->
-                    {'ok',{module(),[fa()],[_],[_]}}.
-
-module(#k_mdef{name=M,exports=Es,attributes=As,body=Fs0}, _Opts) ->
-    Fs1 = functions(Fs0, []),
-    {ok,{M,Es,As,Fs1}}.
-
-functions([F|Fs], Acc) ->
-    functions(Fs, [function(F)|Acc]);
-functions([], Acc) -> reverse(Acc).
-
-%% function(Kfunc) -> Func.
-
-function(#k_fdef{anno=#k{a=Anno},func=F,arity=Ar,vars=Vs,body=Kb}) ->
-    try
-	As = var_list(Vs),
-	Vdb0 = init_vars(As),
-	%% Force a top-level match!
-	B0 = case Kb of
-		 #k_match{} -> Kb;
-		 _ ->
-		     Ka = get_kanno(Kb),
-		     #k_match{anno=#k{us=Ka#k.us,ns=[],a=Ka#k.a},
-			      vars=Vs,body=Kb,ret=[]}
-	     end,
-	{B1,_,Vdb1} = body(B0, 1, Vdb0),
-	{function,F,Ar,As,B1,Vdb1,Anno}
-    catch
-	Class:Error ->
-	    Stack = erlang:get_stacktrace(),
-	    io:fwrite("Function: ~w/~w\n", [F,Ar]),
-	    erlang:raise(Class, Error, Stack)
-    end.
-
-%% body(Kbody, I, Vdb) -> {[Expr],MaxI,Vdb}.
-%%  Handle a body.
-
-body(#k_seq{arg=Ke,body=Kb}, I, Vdb0) ->
-    %%ok = io:fwrite("life ~w:~p~n", [?LINE,{Ke,I,Vdb0}]),
-    A = get_kanno(Ke),
-    Vdb1 = use_vars(union(A#k.us, A#k.ns), I, Vdb0),
-    {Es,MaxI,Vdb2} = body(Kb, I+1, Vdb1),
-    E = expr(Ke, I, Vdb2),
-    {[E|Es],MaxI,Vdb2};
-body(Ke, I, Vdb0) ->
-    %%ok = io:fwrite("life ~w:~p~n", [?LINE,{Ke,I,Vdb0}]),
-    A = get_kanno(Ke),
-    Vdb1 = use_vars(union(A#k.us, A#k.ns), I, Vdb0),
-    E = expr(Ke, I, Vdb1),
-    {[E],I,Vdb1}.
-
-%% protected(Kprotected, I, Vdb) -> Protected.
-%%  Only used in guards.
-
-protected(#k_protected{anno=A,arg=Ts,ret=Rs}, I, Vdb) ->
-    %% Lock variables that are alive before try and used afterwards.
-    %% Don't lock variables that are only used inside the protected
-    %% expression.
-    Pdb0 = vdb_sub(I, I+1, Vdb),
-    {T,MaxI,Pdb1} = body(Ts, I+1, Pdb0),
-    Pdb2 = use_vars(A#k.ns, MaxI+1, Pdb1),	%Save "return" values
-    #l{ke={protected,T,var_list(Rs)},i=I,a=A#k.a,vdb=Pdb2}.
-
-%% expr(Kexpr, I, Vdb) -> Expr.
-
-expr(#k_test{anno=A,op=Op,args=As,inverted=Inverted}, I, _Vdb) ->
-    #l{ke={test,test_op(Op),atomic_list(As),Inverted},i=I,a=A#k.a};
-expr(#k_call{anno=A,op=Op,args=As,ret=Rs}, I, _Vdb) ->
-    #l{ke={call,call_op(Op),atomic_list(As),var_list(Rs)},i=I,a=A#k.a};
-expr(#k_enter{anno=A,op=Op,args=As}, I, _Vdb) ->
-    #l{ke={enter,call_op(Op),atomic_list(As)},i=I,a=A#k.a};
-expr(#k_bif{anno=A,op=Op,args=As,ret=Rs}, I, _Vdb) ->
-    Bif = k_bif(A, Op, As, Rs),
-    #l{ke=Bif,i=I,a=A#k.a};
-expr(#k_match{anno=A,body=Kb,ret=Rs}, I, Vdb) ->
-    %% Work out imported variables which need to be locked.
-    Mdb = vdb_sub(I, I+1, Vdb),
-    M = match(Kb, A#k.us, I+1, [], Mdb),
-    #l{ke={match,M,var_list(Rs)},i=I,vdb=use_vars(A#k.us, I+1, Mdb),a=A#k.a};
-expr(#k_guard_match{anno=A,body=Kb,ret=Rs}, I, Vdb) ->
-    %% Work out imported variables which need to be locked.
-    Mdb = vdb_sub(I, I+1, Vdb),
-    M = match(Kb, A#k.us, I+1, [], Mdb),
-    #l{ke={guard_match,M,var_list(Rs)},i=I,vdb=use_vars(A#k.us, I+1, Mdb),a=A#k.a};
-expr(#k_try{}=Try, I, Vdb) ->
-    body_try(Try, I, Vdb);
-expr(#k_protected{}=Protected, I, Vdb) ->
-    protected(Protected, I, Vdb);
-expr(#k_try_enter{anno=A,arg=Ka,vars=Vs,body=Kb,evars=Evs,handler=Kh}, I, Vdb) ->
-    %% Lock variables that are alive before the catch and used afterwards.
-    %% Don't lock variables that are only used inside the try.
-    Tdb0 = vdb_sub(I, I+1, Vdb),
-    %% This is the tricky bit. Lock variables in Arg that are used in
-    %% the body and handler. Add try tag 'variable'.
-    Ab = get_kanno(Kb),
-    Ah = get_kanno(Kh),
-    Tdb1 = use_vars(union(Ab#k.us, Ah#k.us), I+3, Tdb0),
-    Tdb2 = vdb_sub(I, I+2, Tdb1),
-    Vnames = fun (Kvar) -> Kvar#k_var.name end,	%Get the variable names
-    {Aes,_,Adb} = body(Ka, I+2, add_var({catch_tag,I+1}, I+1, 1000000, Tdb2)),
-    {Bes,_,Bdb} = body(Kb, I+4, new_vars(sort(map(Vnames, Vs)), I+3, Tdb2)),
-    {Hes,_,Hdb} = body(Kh, I+4, new_vars(sort(map(Vnames, Evs)), I+3, Tdb2)),
-    #l{ke={try_enter,#l{ke={block,Aes},i=I+1,vdb=Adb,a=[]},
-	   var_list(Vs),#l{ke={block,Bes},i=I+3,vdb=Bdb,a=[]},
-	   var_list(Evs),#l{ke={block,Hes},i=I+3,vdb=Hdb,a=[]}},
-       i=I,vdb=Tdb1,a=A#k.a};
-expr(#k_catch{anno=A,body=Kb,ret=[R]}, I, Vdb) ->
-    %% Lock variables that are alive before the catch and used afterwards.
-    %% Don't lock variables that are only used inside the catch.
-    %% Add catch tag 'variable'.
-    Cdb0 = vdb_sub(I, I+1, Vdb),
-    {Es,_,Cdb1} = body(Kb, I+1, add_var({catch_tag,I}, I, locked, Cdb0)),
-    #l{ke={'catch',Es,variable(R)},i=I,vdb=Cdb1,a=A#k.a};
-expr(#k_receive{anno=A,var=V,body=Kb,timeout=T,action=Ka,ret=Rs}, I, Vdb) ->
-    %% Work out imported variables which need to be locked.
-    Rdb = vdb_sub(I, I+1, Vdb),
-    M = match(Kb, add_element(V#k_var.name, A#k.us), I+1, [],
-	      new_vars([V#k_var.name], I, Rdb)),
-    {Tes,_,Adb} = body(Ka, I+1, Rdb),
-    #l{ke={receive_loop,atomic(T),variable(V),M,
-	   #l{ke=Tes,i=I+1,vdb=Adb,a=[]},var_list(Rs)},
-       i=I,vdb=use_vars(A#k.us, I+1, Vdb),a=A#k.a};
-expr(#k_receive_accept{anno=A}, I, _Vdb) ->
-    #l{ke=receive_accept,i=I,a=A#k.a};
-expr(#k_receive_next{anno=A}, I, _Vdb) ->
-    #l{ke=receive_next,i=I,a=A#k.a};
-expr(#k_put{anno=A,arg=Arg,ret=Rs}, I, _Vdb) ->
-    #l{ke={set,var_list(Rs),literal(Arg, [])},i=I,a=A#k.a};
-expr(#k_break{anno=A,args=As}, I, _Vdb) ->
-    #l{ke={break,atomic_list(As)},i=I,a=A#k.a};
-expr(#k_guard_break{anno=A,args=As}, I, Vdb) ->
-    Locked = [V || {V,_,_} <- Vdb],
-    #l{ke={guard_break,atomic_list(As),Locked},i=I,a=A#k.a};
-expr(#k_return{anno=A,args=As}, I, _Vdb) ->
-    #l{ke={return,atomic_list(As)},i=I,a=A#k.a}.
-
-body_try(#k_try{anno=A,arg=Ka,vars=Vs,body=Kb,evars=Evs,handler=Kh,ret=Rs},
-	 I, Vdb) ->
-    %% Lock variables that are alive before the catch and used afterwards.
-    %% Don't lock variables that are only used inside the try.
-    Tdb0 = vdb_sub(I, I+1, Vdb),
-    %% This is the tricky bit. Lock variables in Arg that are used in
-    %% the body and handler. Add try tag 'variable'.
-    Ab = get_kanno(Kb),
-    Ah = get_kanno(Kh),
-    Tdb1 = use_vars(union(Ab#k.us, Ah#k.us), I+3, Tdb0),
-    Tdb2 = vdb_sub(I, I+2, Tdb1),
-    Vnames = fun (Kvar) -> Kvar#k_var.name end,	%Get the variable names
-    {Aes,_,Adb} = body(Ka, I+2, add_var({catch_tag,I+1}, I+1, locked, Tdb2)),
-    {Bes,_,Bdb} = body(Kb, I+4, new_vars(sort(map(Vnames, Vs)), I+3, Tdb2)),
-    {Hes,_,Hdb} = body(Kh, I+4, new_vars(sort(map(Vnames, Evs)), I+3, Tdb2)),
-    #l{ke={'try',#l{ke={block,Aes},i=I+1,vdb=Adb,a=[]},
-	   var_list(Vs),#l{ke={block,Bes},i=I+3,vdb=Bdb,a=[]},
-	   var_list(Evs),#l{ke={block,Hes},i=I+3,vdb=Hdb,a=[]},
-	   var_list(Rs)},
-       i=I,vdb=Tdb1,a=A#k.a}.
-
-%% call_op(Op) -> Op.
-%% test_op(Op) -> Op.
-%%  Do any necessary name translations here to munge into beam format.
-
-call_op(#k_local{name=N}) -> N; 
-call_op(#k_remote{mod=M,name=N}) -> {remote,atomic(M),atomic(N)};
-call_op(Other) -> variable(Other).
-
-test_op(#k_remote{mod=#k_atom{val=erlang},name=#k_atom{val=N}}) -> N.
-
-%% k_bif(Anno, Op, [Arg], [Ret], Vdb) -> Expr.
-%%  Build bifs.
-
-k_bif(_A, #k_internal{name=Name}, As, Rs) ->
-    {internal,Name,atomic_list(As),var_list(Rs)};
-k_bif(_A, #k_remote{mod=#k_atom{val=erlang},name=#k_atom{val=Name}}, As, Rs) ->
-    Ar = length(As),
-    case is_gc_bif(Name, Ar) of
-	false ->
-	    {bif,Name,atomic_list(As),var_list(Rs)};
-	true ->
-	    {gc_bif,Name,atomic_list(As),var_list(Rs)}
-    end.
-
-%% match(Kexpr, [LockVar], I, Vdb) -> Expr.
-%%  Convert match tree to old format.
-
-match(#k_alt{anno=A,first=Kf,then=Kt}, Ls, I, Ctxt, Vdb0) ->
-    Vdb1 = use_vars(union(A#k.us, Ls), I, Vdb0),
-    F = match(Kf, Ls, I+1, Ctxt, Vdb1),
-    T = match(Kt, Ls, I+1, Ctxt, Vdb1),
-    #l{ke={alt,F,T},i=I,vdb=Vdb1,a=A#k.a};
-match(#k_select{anno=A,var=V,types=Kts}, Ls0, I, Ctxt, Vdb0) ->
-    Vanno = get_kanno(V),
-    Ls1 = case member(no_usage, Vanno) of
-	      false -> add_element(V#k_var.name, Ls0);
-	      true -> Ls0
-	  end,
-    Anno = case member(reuse_for_context, Vanno) of
-	       true -> [reuse_for_context|A#k.a];
-	       false -> A#k.a
-	   end,
-    Vdb1 = use_vars(union(A#k.us, Ls1), I, Vdb0),
-    Ts = [type_clause(Tc, Ls1, I+1, Ctxt, Vdb1) || Tc <- Kts],
-    #l{ke={select,literal(V, Ctxt),Ts},i=I,vdb=Vdb1,a=Anno};
-match(#k_guard{anno=A,clauses=Kcs}, Ls, I, Ctxt, Vdb0) ->
-    Vdb1 = use_vars(union(A#k.us, Ls), I, Vdb0),
-    Cs = [guard_clause(G, Ls, I+1, Ctxt, Vdb1) || G <- Kcs],
-    #l{ke={guard,Cs},i=I,vdb=Vdb1,a=A#k.a};
-match(Other, Ls, I, _Ctxt, Vdb0) ->
-    Vdb1 = use_vars(Ls, I, Vdb0),
-    {B,_,Vdb2} = body(Other, I+1, Vdb1),
-    #l{ke={block,B},i=I,vdb=Vdb2,a=[]}.
-
-type_clause(#k_type_clause{anno=A,type=T,values=Kvs}, Ls, I, Ctxt, Vdb0) ->
-    %%ok = io:format("life ~w: ~p~n", [?LINE,{T,Kvs}]),
-    Vdb1 = use_vars(union(A#k.us, Ls), I+1, Vdb0),
-    Vs = [val_clause(Vc, Ls, I+1, Ctxt, Vdb1) || Vc <- Kvs],
-    #l{ke={type_clause,type(T),Vs},i=I,vdb=Vdb1,a=A#k.a}.
-
-val_clause(#k_val_clause{anno=A,val=V,body=Kb}, Ls0, I, Ctxt0, Vdb0) ->
-    New = (get_kanno(V))#k.ns,
-    Bus = (get_kanno(Kb))#k.us,
-    %%ok = io:format("Ls0 = ~p, Used=~p\n  New=~p, Bus=~p\n", [Ls0,Used,New,Bus]),
-    Ls1 = union(intersection(New, Bus), Ls0),	%Lock for safety
-    Vdb1 = use_vars(union(A#k.us, Ls1), I+1, new_vars(New, I, Vdb0)),
-    Ctxt = case V of
-	       #k_binary{segs=#k_var{name=C0}} -> C0;
-	       _ -> Ctxt0
-	   end,
-    B = match(Kb, Ls1, I+1, Ctxt, Vdb1),
-    #l{ke={val_clause,literal(V, Ctxt),B},i=I,vdb=use_vars(Bus, I+1, Vdb1),a=A#k.a}.
-
-guard_clause(#k_guard_clause{anno=A,guard=Kg,body=Kb}, Ls, I, Ctxt, Vdb0) ->
-    Vdb1 = use_vars(union(A#k.us, Ls), I+2, Vdb0),
-    Gdb = vdb_sub(I+1, I+2, Vdb1),
-    G = protected(Kg, I+1, Gdb),
-    B = match(Kb, Ls, I+2, Ctxt, Vdb1),
-    #l{ke={guard_clause,G,B},
-       i=I,vdb=use_vars((get_kanno(Kg))#k.us, I+2, Vdb1),
-       a=A#k.a}.
-
-%% type(Ktype) -> Type.
-
-type(k_literal) -> literal;
-type(k_int) -> integer;
-%%type(k_char) -> integer;			%Hhhmmm???
-type(k_float) -> float;
-type(k_atom) -> atom;
-type(k_nil) -> nil;
-type(k_cons) -> cons;
-type(k_tuple) -> tuple;
-type(k_binary) -> binary;
-type(k_bin_seg) -> bin_seg;
-type(k_bin_int) -> bin_int;
-type(k_bin_end) -> bin_end;
-type(k_map) -> map.
-
-%% variable(Klit) -> Lit.
-%% var_list([Klit]) -> [Lit].
-
-variable(#k_var{name=N}) -> {var,N}.
-
-var_list(Ks) -> [variable(K) || K <- Ks].
-
-%% atomic(Klit) -> Lit.
-%% atomic_list([Klit]) -> [Lit].
-
-atomic(#k_literal{val=V}) -> {literal,V};
-atomic(#k_var{name=N}) -> {var,N};
-atomic(#k_int{val=I}) -> {integer,I};
-atomic(#k_float{val=F}) -> {float,F};
-atomic(#k_atom{val=N}) -> {atom,N};
-%%atomic(#k_char{val=C}) -> {char,C};
-atomic(#k_nil{}) -> nil.
-
-atomic_list(Ks) -> [atomic(K) || K <- Ks].
-
-%% literal(Klit) -> Lit.
-%% literal_list([Klit]) -> [Lit].
-
-literal(#k_var{name=N}, _) -> {var,N};
-literal(#k_literal{val=I}, _) -> {literal,I};
-literal(#k_int{val=I}, _) -> {integer,I};
-literal(#k_float{val=F}, _) -> {float,F};
-literal(#k_atom{val=N}, _) -> {atom,N};
-%%literal(#k_char{val=C}, _) -> {char,C};
-literal(#k_nil{}, _) -> nil;
-literal(#k_cons{hd=H,tl=T}, Ctxt) ->
-    {cons,[literal(H, Ctxt),literal(T, Ctxt)]};
-literal(#k_binary{segs=V}, Ctxt) ->
-    {binary,literal(V, Ctxt)};
-literal(#k_bin_seg{size=S,unit=U,type=T,flags=Fs,seg=Seg,next=[]}, Ctxt) ->
-    %% Only occurs in patterns.
-    {bin_seg,Ctxt,literal(S, Ctxt),U,T,Fs,[literal(Seg, Ctxt)]};
-literal(#k_bin_seg{size=S,unit=U,type=T,flags=Fs,seg=Seg,next=N}, Ctxt) ->
-    {bin_seg,Ctxt,literal(S, Ctxt),U,T,Fs,
-     [literal(Seg, Ctxt),literal(N, Ctxt)]};
-literal(#k_bin_int{size=S,unit=U,flags=Fs,val=Int,next=N}, Ctxt) ->
-    %% Only occurs in patterns.
-    {bin_int,Ctxt,literal(S, Ctxt),U,Fs,Int,
-     [literal(N, Ctxt)]};
-literal(#k_bin_end{}, Ctxt) ->
-    {bin_end,Ctxt};
-literal(#k_tuple{es=Es}, Ctxt) ->
-    {tuple,literal_list(Es, Ctxt)};
-literal(#k_map{op=Op,var=Var,es=Es0}, Ctxt) ->
-    {map,Op,literal(Var, Ctxt),literal_list(Es0, Ctxt)};
-literal(#k_map_pair{key=K,val=V}, Ctxt) ->
-    {map_pair,literal(K, Ctxt),literal(V, Ctxt)}.
-
-literal_list(Ks, Ctxt) ->
-    [literal(K, Ctxt) || K <- Ks].
-
-
-%% is_gc_bif(Name, Arity) -> true|false
-%%  Determines whether the BIF Name/Arity might do a GC.
-
-is_gc_bif(hd, 1) -> false;
-is_gc_bif(tl, 1) -> false;
-is_gc_bif(self, 0) -> false;
-is_gc_bif(node, 0) -> false;
-is_gc_bif(node, 1) -> false;
-is_gc_bif(element, 2) -> false;
-is_gc_bif(get, 1) -> false;
-is_gc_bif(tuple_size, 1) -> false;
-is_gc_bif(Bif, Arity) ->
-    not (erl_internal:bool_op(Bif, Arity) orelse
-	 erl_internal:new_type_test(Bif, Arity) orelse
-	 erl_internal:comp_op(Bif, Arity)).
-
-%% Keep track of life time for variables.
-%%
-%% init_vars([{var,VarName}]) -> Vdb.
-%% new_vars([VarName], I, Vdb) -> Vdb.
-%% use_vars([VarName], I, Vdb) -> Vdb.
-%% add_var(VarName, F, L, Vdb) -> Vdb.
-%%
-%% The list of variable names for new_vars/3 and use_vars/3
-%% must be sorted.
-
-init_vars(Vs) ->
-    vdb_new(Vs).
-
-new_vars([], _, Vdb) -> Vdb;
-new_vars([V], I, Vdb) -> vdb_store_new(V, {V,I,I}, Vdb);
-new_vars(Vs, I, Vdb) -> vdb_update_vars(Vs, Vdb, I).
-
-use_vars([], _, Vdb) ->
-    Vdb;
-use_vars([V], I, Vdb) ->
-    case vdb_find(V, Vdb) of
-	{V,F,L} when I > L -> vdb_update(V, {V,F,I}, Vdb);
-	{V,_,_} -> Vdb;
-	error -> vdb_store_new(V, {V,I,I}, Vdb)
-    end;
-use_vars(Vs, I, Vdb) -> vdb_update_vars(Vs, Vdb, I).
-
-add_var(V, F, L, Vdb) ->
-    vdb_store_new(V, {V,F,L}, Vdb).
-
-%% vdb
-
-vdb_new(Vs) ->
-    sort([{V,0,0} || {var,V} <- Vs]).
-
--type var() :: atom().
-
--spec vdb_find(var(), [vdb_entry()]) -> 'error' | vdb_entry().
-
-vdb_find(V, Vdb) ->
-    case lists:keyfind(V, 1, Vdb) of
-	false -> error;
-	Vd -> Vd
-    end.
-
-vdb_update(V, Update, [{V,_,_}|Vdb]) ->
-    [Update|Vdb];
-vdb_update(V, Update, [Vd|Vdb]) ->
-    [Vd|vdb_update(V, Update, Vdb)].
-
-vdb_store_new(V, New, [{V1,_,_}=Vd|Vdb]) when V > V1 ->
-    [Vd|vdb_store_new(V, New, Vdb)];
-vdb_store_new(V, New, [{V1,_,_}|_]=Vdb) when V < V1 ->
-    [New|Vdb];
-vdb_store_new(_, New, []) -> [New].
-
-vdb_update_vars([V|_]=Vs, [{V1,_,_}=Vd|Vdb], I) when V > V1 ->
-    [Vd|vdb_update_vars(Vs, Vdb, I)];
-vdb_update_vars([V|Vs], [{V1,_,_}|_]=Vdb, I) when V < V1 ->
-    %% New variable.
-    [{V,I,I}|vdb_update_vars(Vs, Vdb, I)];
-vdb_update_vars([V|Vs], [{_,F,L}=Vd|Vdb], I) ->
-    %% Existing variable.
-    if
-	I > L -> [{V,F,I}|vdb_update_vars(Vs, Vdb, I)];
-	true ->  [Vd|vdb_update_vars(Vs, Vdb, I)]
-    end;
-vdb_update_vars([V|Vs], [], I) ->
-    %% New variable.
-    [{V,I,I}|vdb_update_vars(Vs, [], I)];
-vdb_update_vars([], Vdb, _) -> Vdb.
-
-%% vdb_sub(Min, Max, Vdb) -> Vdb.
-%%  Extract variables which are used before and after Min.  Lock
-%%  variables alive after Max.
-
-vdb_sub(Min, Max, Vdb) ->
-    [ if L >= Max -> {V,F,locked};
-	 true -> Vd
-      end || {V,F,L}=Vd <- Vdb, F < Min, L >= Min ].
diff --git a/lib/compiler/test/Makefile b/lib/compiler/test/Makefile
index 63763f31b2..da5d207db9 100644
--- a/lib/compiler/test/Makefile
+++ b/lib/compiler/test/Makefile
@@ -22,6 +22,7 @@ MODULES= \
 	bs_construct_SUITE \
 	bs_match_SUITE \
 	bs_utf_SUITE \
+	core_alias_SUITE \
 	core_fold_SUITE \
 	compile_SUITE \
 	compilation_SUITE \
diff --git a/lib/compiler/test/beam_utils_SUITE.erl b/lib/compiler/test/beam_utils_SUITE.erl
index 710cb050d4..7686e69b63 100644
--- a/lib/compiler/test/beam_utils_SUITE.erl
+++ b/lib/compiler/test/beam_utils_SUITE.erl
@@ -24,7 +24,8 @@
 	 apply_fun/1,apply_mf/1,bs_init/1,bs_save/1,
 	 is_not_killed/1,is_not_used_at/1,
 	 select/1,y_catch/1,otp_8949_b/1,liveopt/1,coverage/1,
-	 y_registers/1]).
+         y_registers/1,user_predef/1,scan_f/1,cafu/1,
+         receive_label/1,read_size_file_version/1]).
 -export([id/1]).
 
 suite() -> [{ct_hooks,[ts_install_cth]}].
@@ -46,7 +47,11 @@ groups() ->
        otp_8949_b,
        liveopt,
        coverage,
-       y_registers
+       y_registers,
+       user_predef,
+       scan_f,
+       cafu,
+       read_size_file_version
       ]}].
 
 init_per_suite(Config) ->
@@ -117,6 +122,15 @@ bs_init(_Config) ->
     {'EXIT',{badarg,_}} = (catch do_bs_init_2([0.5])),
     {'EXIT',{badarg,_}} = (catch do_bs_init_2([-1])),
     {'EXIT',{badarg,_}} = (catch do_bs_init_2([1 bsl 32])),
+
+    <<>> = do_bs_init_3({tag,0}, 0, 0),
+    <<0>> = do_bs_init_3({tag,0}, 2, 1),
+
+    <<"_build/shared">> = do_bs_init_4([], false),
+    <<"abc/shared">> = do_bs_init_4(<<"abc">>, false),
+    <<"foo/foo">> = do_bs_init_4(<<"foo">>, true),
+    error = do_bs_init_4([], not_boolean),
+
     ok.
 
 do_bs_init_1([?MODULE], Sz) ->
@@ -134,6 +148,45 @@ do_bs_init_2(SigNos) ->
 	    erlang:error(badarg)
     >>.
 
+do_bs_init_3({tag,Pos}, Offset, Len) ->
+    N0 = Offset - Pos,
+    N = if N0 > Len -> Len;
+           true -> N0
+        end,
+    <<0:N/unit:8>>.
+
+do_bs_init_4(Arg1, Arg2) ->
+    Build =
+        case id(Arg1) of
+            X when X =:= [] orelse X =:= false -> <<"_build">>;
+            X -> X
+        end,
+    case id(Arg2) of
+        true ->
+            id(<<case Build of
+                     Rewrite when is_binary(Rewrite) ->
+                         Rewrite;
+                     Rewrite ->
+                         id(Rewrite)
+                 end/binary,
+                 "/",
+                 case id(<<"foo">>) of
+                     Rewrite when is_binary(Rewrite) ->
+                         Rewrite;
+                     Rewrite ->
+                         id(Rewrite)
+                 end/binary>>);
+        false ->
+            id(<<case Build of
+                     Rewrite when is_binary(Rewrite) ->
+                         Rewrite;
+                     Rewrite ->
+                         id(Rewrite)
+                 end/binary,
+                 "/shared">>);
+        Other ->
+            error
+    end.
 
 bs_save(_Config) ->
     {a,30,<<>>} = do_bs_save(<<1:1,30:5>>),
@@ -376,5 +429,83 @@ do(A, B) -> {A,B}.
 appointment(#{"resolution" := Url}) ->
     do(receive _ -> Url end, #{true => Url}).
 
+%% From epp.erl.
+user_predef(_Config) ->
+    #{key:="value"} = user_predef({key,"value"}, #{}),
+    #{key:="value"} = user_predef({key,"value"}, #{key=>defined}),
+    error = user_predef({key,"value"}, #{key=>[defined]}),
+    ok.
+
+user_predef({M,Val}, Ms) ->
+    case Ms of
+	#{M:=Defs} when is_list(Defs) ->
+	    error;
+	_ ->
+	    Ms#{M=>Val}
+    end.
+
+%% From disk_log_1.erl.
+scan_f(_Config) ->
+    {1,<<>>,[]} = scan_f(<<1:32>>, 1, []),
+    {1,<<>>,[<<156>>]} = scan_f(<<1:32,156,1:32>>, 1, []),
+    ok.
+
+scan_f(<<Size:32,Tail/binary>>, FSz, Acc) when Size =< FSz ->
+    case Tail of
+        <<BinTerm:Size/binary,Tail2/binary>> ->
+            scan_f(Tail2, FSz, [BinTerm | Acc]);
+        _ ->
+            {Size,Tail,Acc}
+    end.
+
+%% From file_io_server.erl.
+cafu(_Config) ->
+    error = cafu(<<42:32>>, -1, 0, {utf32,big}),
+    error = cafu(<<42:32>>, 10, 0, {utf32,big}),
+    error = cafu(<<42:32>>, -1, 0, {utf32,little}),
+    ok.
+
+cafu(<<_/big-utf32,Rest/binary>>, N, Count, {utf32,big}) when N < 0 ->
+    cafu(Rest, -1, Count+1, {utf32,big});
+cafu(<<_/big-utf32,Rest/binary>>, N, Count, {utf32,big}) ->
+    cafu(Rest, N-1, Count+1, {utf32,big});
+cafu(<<_/little-utf32,Rest/binary>>, N, Count, {utf32,little}) when N < 0 ->
+    cafu(Rest, -1, Count+1, {utf32,little});
+cafu(_, _, _, _) ->
+    error.
+
+-record(rec_label, {bool}).
+
+receive_label(_Config) ->
+    Pid = spawn_link(fun() -> do_receive_label(#rec_label{bool=true}) end),
+    Msg = {a,b,c},
+    Pid ! {self(),Msg},
+    receive
+        {ok,Msg} ->
+            unlink(Pid),
+            exit(Pid, die),
+            ok
+    end.
+
+do_receive_label(Rec) ->
+    receive
+        {From,Message} when Rec#rec_label.bool ->
+            From ! {ok,Message},
+            do_receive_label(Rec)
+    end.
+
+read_size_file_version(_Config) ->
+    ok = do_read_size_file_version({ok,<<42>>}),
+    {ok,7777} = do_read_size_file_version({ok,<<7777:32>>}),
+    ok.
+
+do_read_size_file_version(E) ->
+    case E of
+	{ok,<<Version>>} when Version =:= 42 ->
+            ok;
+	{ok,<<MaxFiles:32>>} ->
+            {ok,MaxFiles}
+    end.
+
 %% The identity function.
 id(I) -> I.
diff --git a/lib/compiler/test/beam_validator_SUITE.erl b/lib/compiler/test/beam_validator_SUITE.erl
index c23514b36b..685eb2a72e 100644
--- a/lib/compiler/test/beam_validator_SUITE.erl
+++ b/lib/compiler/test/beam_validator_SUITE.erl
@@ -421,9 +421,9 @@ try_bin_opt(Mod) ->
     try
 	do_bin_opt(Mod)
     catch
-	Class:Error ->
+	Class:Error:Stk ->
 	    io:format("~p: ~p ~p\n~p\n",
-		      [Mod,Class,Error,erlang:get_stacktrace()]),
+		      [Mod,Class,Error,Stk]),
 	    error
     end.
 
diff --git a/lib/compiler/test/bs_match_SUITE.erl b/lib/compiler/test/bs_match_SUITE.erl
index 2fe8cd0cff..7e1a432511 100644
--- a/lib/compiler/test/bs_match_SUITE.erl
+++ b/lib/compiler/test/bs_match_SUITE.erl
@@ -39,7 +39,8 @@
 	 match_string_opt/1,select_on_integer/1,
 	 map_and_binary/1,unsafe_branch_caching/1,
 	 bad_literals/1,good_literals/1,constant_propagation/1,
-	 parse_xml/1,get_payload/1,num_slots_different/1]).
+	 parse_xml/1,get_payload/1,escape/1,num_slots_different/1,
+         check_bitstring_list/1,guard/1]).
 
 -export([coverage_id/1,coverage_external_ignore/2]).
 
@@ -71,7 +72,8 @@ groups() ->
        match_string_opt,select_on_integer,
        map_and_binary,unsafe_branch_caching,
        bad_literals,good_literals,constant_propagation,parse_xml,
-       get_payload,num_slots_different]}].
+       get_payload,escape,num_slots_different,
+       check_bitstring_list,guard]}].
 
 
 init_per_suite(Config) ->
@@ -1524,6 +1526,21 @@ do_get_payload(ExtHdr) ->
     <<_:13,_:35>> = ExtHdr#ext_header.ext_hdr_opts,
     ExtHdrOptions.
 
+escape(_Config) ->
+    0 = escape(<<>>, 0),
+    1 = escape(<<128>>, 0),
+    2 = escape(<<128,255>>, 0),
+    42 = escape(<<42>>, 0),
+    50 = escape(<<42,8>>, 0),
+    ok.
+
+escape(<<Byte, Rest/bits>>, Pos) when Byte >= 127 ->
+    escape(Rest, Pos + 1);
+escape(<<Byte, Rest/bits>>, Pos) ->
+    escape(Rest, Pos + Byte);
+escape(<<_Rest/bits>>, Pos) ->
+    Pos.
+
 %% ERL-490
 num_slots_different(_Config) ->
     Ts = [{<<"de">>, <<"default">>, <<"Remove">>, <<"a">>},
@@ -1557,6 +1574,32 @@ lgettext(<<"de">>, <<"navigation">>, <<"Results">>) ->
 lgettext(<<"de">>, <<"navigation">>, <<"Resources">>) ->
     {ok, <<"Ressourcen">>}.
 
+%% Cover more code in beam_bsm.
+check_bitstring_list(_Config) ->
+    true = check_bitstring_list(<<1:1,0:1,1:1,1:1>>, [1,0,1,1]),
+    false = check_bitstring_list(<<1:1,0:1,1:1,1:1>>, [0]),
+    ok.
+
+check_bitstring_list(<<H:1,T1/bitstring>>, [H|T2]) ->
+    check_bitstring_list(T1, T2);
+check_bitstring_list(<<>>, []) ->
+    true;
+check_bitstring_list(_, _) ->
+    false.
+
+guard(_Config) ->
+    Tuple = id({a,b}),
+    ok = guard_1(<<1,2,3>>, {1,2,3}),
+    ok = guard_2(<<42>>, #{}),
+    ok.
+
+%% Cover handling of #k_put{} in v3_codegen:bsm_rename_ctx/4.
+guard_1(<<A,B,C>>, Tuple) when Tuple =:= {A,B,C} ->
+    ok.
+
+%% Cover handling of #k_call{} in v3_codegen:bsm_rename_ctx/4.
+guard_2(<<_>>, Healing) when Healing#{[] => Healing} =:= #{[] => #{}} ->
+    ok.
 
 check(F, R) ->
     R = F().
diff --git a/lib/compiler/test/compilation_SUITE_data/opt_crash.erl b/lib/compiler/test/compilation_SUITE_data/opt_crash.erl
index f1607cca68..c65ec31593 100644
--- a/lib/compiler/test/compilation_SUITE_data/opt_crash.erl
+++ b/lib/compiler/test/compilation_SUITE_data/opt_crash.erl
@@ -33,7 +33,7 @@ test() ->
                {userinfo,nil},
                fun() -> nil end},
             nil},
-         {'query',nil}}},
+         {query,nil}}},
 
    {absoluteURI,
       {scheme,_},
@@ -43,7 +43,7 @@ test() ->
                {userinfo,nil},
                HostportBefore},
             nil},
-         {'query',nil}}} = URI_Before,
+         {query,nil}}} = URI_Before,
 
    %% ... some funky code ommitted, not relevant ...
 
@@ -55,7 +55,7 @@ test() ->
                {userinfo,nil},
                HostportAfter},
             nil},
-         {'query',nil}}} = URI_Before,
+         {query,nil}}} = URI_Before,
    %% NOTE: I intended to write URI_After instead of URI_Before
    %% but the accident revealed that when you add the line below,
    %% it causes internal error in v3_codegen on compilation
diff --git a/lib/compiler/test/compile_SUITE.erl b/lib/compiler/test/compile_SUITE.erl
index 96897d612d..35c11d894d 100644
--- a/lib/compiler/test/compile_SUITE.erl
+++ b/lib/compiler/test/compile_SUITE.erl
@@ -27,12 +27,12 @@
 -export([all/0, suite/0,groups/0,init_per_suite/1, end_per_suite/1, 
 	 init_per_group/2,end_per_group/2,
 	 app_test/1,appup_test/1,
-	 debug_info/4, custom_debug_info/1,
+	 debug_info/4, custom_debug_info/1, custom_compile_info/1,
 	 file_1/1, forms_2/1, module_mismatch/1, big_file/1, outdir/1,
 	 binary/1, makedep/1, cond_and_ifdef/1, listings/1, listings_big/1,
 	 other_output/1, kernel_listing/1, encrypted_abstr/1,
 	 strict_record/1, utf8_atoms/1, utf8_functions/1, extra_chunks/1,
-	 cover/1, env/1, core_pp/1,
+	 cover/1, env/1, core_pp/1, tuple_calls/1,
 	 core_roundtrip/1, asm/1, optimized_guards/1,
 	 sys_pre_attributes/1, dialyzer/1,
 	 warnings/1, pre_load_check/1, env_compiler_options/1,
@@ -49,11 +49,12 @@ all() ->
     test_lib:recompile(?MODULE),
     [app_test, appup_test, file_1, forms_2, module_mismatch, big_file, outdir,
      binary, makedep, cond_and_ifdef, listings, listings_big,
-     other_output, kernel_listing, encrypted_abstr,
+     other_output, kernel_listing, encrypted_abstr, tuple_calls,
      strict_record, utf8_atoms, utf8_functions, extra_chunks,
      cover, env, core_pp, core_roundtrip, asm, optimized_guards,
      sys_pre_attributes, dialyzer, warnings, pre_load_check,
-     env_compiler_options, custom_debug_info, bc_options].
+     env_compiler_options, custom_debug_info, bc_options,
+     custom_compile_info].
 
 groups() -> 
     [].
@@ -384,7 +385,6 @@ do_file_listings(DataDir, PrivDir, [File|Files]) ->
     do_listing(Simple, TargetDir, dcbsm, ".core_bsm"),
     do_listing(Simple, TargetDir, dsetel, ".dsetel"),
     do_listing(Simple, TargetDir, dkern, ".kernel"),
-    do_listing(Simple, TargetDir, dlife, ".life"),
     do_listing(Simple, TargetDir, dcg, ".codegen"),
     do_listing(Simple, TargetDir, dblk, ".block"),
     do_listing(Simple, TargetDir, dexcept, ".except"),
@@ -500,9 +500,8 @@ do_kernel_listing({M,A}) ->
 	    io:format("*** compilation failure '~p' for module ~s\n",
 		      [Error,M]),
 	    error;
-	Class:Error ->
-	    io:format("~p: ~p ~p\n~p\n",
-		      [M,Class,Error,erlang:get_stacktrace()]),
+	Class:Error:Stk ->
+	    io:format("~p: ~p ~p\n~p\n", [M,Class,Error,Stk]),
 	    error
     end.
 
@@ -661,6 +660,23 @@ custom_debug_info(Config) when is_list(Config) ->
     {ok,{simple,[{debug_info,{debug_info_v1,?MODULE,error}}]}} =
 	beam_lib:chunks(ErrorBin, [debug_info]).
 
+custom_compile_info(Config) when is_list(Config) ->
+    Anno = erl_anno:new(1),
+    Forms = [{attribute,Anno,module,custom_compile_info}],
+    Opts = [binary,{compile_info,[{another,version}]}],
+
+    {ok,custom_compile_info,Bin} = compile:forms(Forms, Opts),
+    {ok,{custom_compile_info,[{compile_info,CompileInfo}]}} =
+	beam_lib:chunks(Bin, [compile_info]),
+    version = proplists:get_value(another, CompileInfo),
+    CompileOpts = proplists:get_value(options, CompileInfo),
+    undefined = proplists:get_value(compile_info, CompileOpts),
+
+    {ok,custom_compile_info,DetBin} = compile:forms(Forms, [deterministic|Opts]),
+    {ok,{custom_compile_info,[{compile_info,DetInfo}]}} =
+	beam_lib:chunks(DetBin, [compile_info]),
+    version = proplists:get_value(another, DetInfo).
+
 cover(Config) when is_list(Config) ->
     io:format("~p\n", [compile:options()]),
     ok.
@@ -793,6 +809,37 @@ extra_chunks(Config) when is_list(Config) ->
     {ok,{extra_chunks,[{"ExCh",<<"Contents">>}]}} =
 	beam_lib:chunks(ExtraChunksBinary, ["ExCh"]).
 
+tuple_calls(Config) when is_list(Config) ->
+    Anno = erl_anno:new(1),
+    Forms = [{attribute,Anno,export,[{size,1},{store,1}]},
+	     {function,Anno,size,1,
+	      [{clause,Anno,[{var,[],mod}],[],
+	       [{call,[],{remote,[],{var,[],mod},{atom,[],size}},[]}]}]},
+	     {function,Anno,store,1,
+	      [{clause,Anno,[{var,[],mod}],[],
+	       [{call,[],{remote,[],{var,[],mod},{atom,[],store}},[{atom,[],key},{atom,[],value}]}]}]}],
+
+    TupleCallsFalse = [{attribute,Anno,module,tuple_calls_false}|Forms],
+    {ok,_,TupleCallsFalseBinary} = compile:forms(TupleCallsFalse, [binary]),
+    code:load_binary(tuple_calls_false, "compile_SUITE.erl", TupleCallsFalseBinary),
+    {'EXIT',{badarg,_}} = (catch tuple_calls_false:store(dict())),
+    {'EXIT',{badarg,_}} = (catch tuple_calls_false:size(dict())),
+    {'EXIT',{badarg,_}} = (catch tuple_calls_false:size(empty_tuple())),
+
+    TupleCallsTrue = [{attribute,Anno,module,tuple_calls_true}|Forms],
+    {ok,_,TupleCallsTrueBinary} = compile:forms(TupleCallsTrue, [binary,tuple_calls]),
+    code:load_binary(tuple_calls_true, "compile_SUITE.erl", TupleCallsTrueBinary),
+    Dict = tuple_calls_true:store(dict()),
+    1 = tuple_calls_true:size(Dict),
+    {'EXIT',{badarg,_}} = (catch tuple_calls_true:size(empty_tuple())),
+
+    ok.
+
+dict() ->
+    dict:new().
+empty_tuple() ->
+    {}.
+
 env(Config) when is_list(Config) ->
     {Simple,Target} = get_files(Config, simple, env),
     {ok,Cwd} = file:get_cwd(),
@@ -854,9 +901,8 @@ do_core_pp({M,A}, Outdir) ->
 	    io:format("*** compilation failure '~p' for module ~s\n",
 		      [Error,M]),
 	    error;
-	Class:Error ->
-	    io:format("~p: ~p ~p\n~p\n",
-		      [M,Class,Error,erlang:get_stacktrace()]),
+	Class:Error:Stk ->
+	    io:format("~p: ~p ~p\n~p\n", [M,Class,Error,Stk]),
 	    error
     end.
 
@@ -913,9 +959,8 @@ do_core_roundtrip(Beam, Outdir) ->
 	    io:format("*** compilation failure '~p' for file ~s\n",
 		      [Error,Beam]),
 	    error;
-	Class:Error ->
-	    io:format("~p: ~p ~p\n~p\n",
-		      [Beam,Class,Error,erlang:get_stacktrace()]),
+	Class:Error:Stk ->
+	    io:format("~p: ~p ~p\n~p\n", [Beam,Class,Error,Stk]),
 	    error
     end.
 
@@ -1100,9 +1145,8 @@ do_asm(Beam, Outdir) ->
 			  [Other,AsmFile]),
 		error
 	end
-    catch Class:Error ->
-	    io:format("~p: ~p ~p\n~p\n",
-		      [M,Class,Error,erlang:get_stacktrace()]),
+    catch Class:Error:Stk ->
+	    io:format("~p: ~p ~p\n~p\n", [M,Class,Error,Stk]),
 	    error
     end.
 
@@ -1119,9 +1163,8 @@ do_opt_guards(Beam) ->
     try
 	{ok,M,Asm} = compile:forms(A, ['S']),
 	do_opt_guards_mod(Asm)
-    catch Class:Error ->
-	    io:format("~p: ~p ~p\n~p\n",
-		      [M,Class,Error,erlang:get_stacktrace()]),
+    catch Class:Error:Stk ->
+	    io:format("~p: ~p ~p\n~p\n", [M,Class,Error,Stk]),
 	    error
     end.
 
@@ -1282,10 +1325,13 @@ do_warnings_2([], Next, F) ->
 %% pre-loads the modules that are used by a typical compilation.
 
 pre_load_check(Config) ->
-    case test_server:is_cover() of
-	true ->
+    case {test_server:is_cover(),code:module_info(native)} of
+	{true,_} ->
 	    {skip,"Cover is running"};
-	false ->
+        {false,true} ->
+            %% Tracing won't work.
+            {skip,"'code' is native-compiled"};
+	{false,false} ->
 	    try
 		do_pre_load_check(Config)
 	    after
diff --git a/lib/compiler/test/core_alias_SUITE.erl b/lib/compiler/test/core_alias_SUITE.erl
new file mode 100644
index 0000000000..f3f15ef0f8
--- /dev/null
+++ b/lib/compiler/test/core_alias_SUITE.erl
@@ -0,0 +1,195 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2007-2016. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(core_alias_SUITE).
+
+-export([all/0, suite/0, groups/0,init_per_suite/1, end_per_suite/1,
+         init_per_group/2, end_per_group/2,
+         tuples/1, cons/1]).
+
+-include_lib("common_test/include/ct.hrl").
+
+suite() -> [{ct_hooks,[ts_install_cth]}].
+
+all() ->
+    test_lib:recompile(?MODULE),
+    [{group,p}].
+
+groups() ->
+    [{p,[parallel],
+      [tuples, cons]}].
+
+init_per_suite(Config) ->
+    Config.
+
+end_per_suite(_Config) ->
+    ok.
+
+init_per_group(_GroupName, Config) ->
+    Config.
+
+end_per_group(_GroupName, Config) ->
+    Config.
+
+
+id(X) -> X.
+
+tuples(Config) when is_list(Config) ->
+    Tuple = {ok,id(value)},
+
+    true = erts_debug:same(Tuple, simple_tuple(Tuple)),
+    true = erts_debug:same(Tuple, simple_tuple_in_map(#{hello => Tuple})),
+    true = erts_debug:same(Tuple, simple_tuple_case_repeated(Tuple, Tuple)),
+    true = erts_debug:same(Tuple, simple_tuple_fun_repeated(Tuple, Tuple)),
+    true = erts_debug:same(Tuple, simple_tuple_twice_head(Tuple, Tuple)),
+
+    {Tuple1, Tuple2} = simple_tuple_twice_body(Tuple),
+    true = erts_debug:same(Tuple, Tuple1),
+    true = erts_debug:same(Tuple, Tuple2),
+
+    Nested = {nested,Tuple},
+    true = erts_debug:same(Tuple, nested_tuple_part(Nested)),
+    true = erts_debug:same(Nested, nested_tuple_whole(Nested)),
+    true = erts_debug:same(Nested, nested_tuple_with_alias(Nested)),
+
+    true = erts_debug:same(Tuple, tuple_rebinding_after(Tuple)),
+
+    Tuple = unaliased_tuple_rebinding_before(Tuple),
+    false = erts_debug:same(Tuple, unaliased_tuple_rebinding_before(Tuple)),
+    Nested = unaliased_literal_tuple_head(Nested),
+    false = erts_debug:same(Nested, unaliased_literal_tuple_head(Nested)),
+    Nested = unaliased_literal_tuple_body(Nested),
+    false = erts_debug:same(Nested, unaliased_literal_tuple_body(Nested)),
+    Nested = unaliased_different_var_tuple(Nested, Tuple),
+    false = erts_debug:same(Nested, unaliased_different_var_tuple(Nested, Tuple)).
+
+simple_tuple({ok,X}) ->
+    {ok,X}.
+simple_tuple_twice_head({ok,X}, {ok,X}) ->
+    {ok,X}.
+simple_tuple_twice_body({ok,X}) ->
+    {{ok,X},{ok,X}}.
+simple_tuple_in_map(#{hello := {ok,X}}) ->
+    {ok,X}.
+simple_tuple_fun_repeated({ok,X}, Y) ->
+    io:format("~p~n", [X]),
+    (fun({ok,X}) -> {ok,X} end)(Y).
+simple_tuple_case_repeated({ok,X}, Y) ->
+    io:format("~p~n", [X]),
+    case Y of {ok,X} -> {ok,X} end.
+
+nested_tuple_part({nested,{ok,X}}) ->
+    {ok,X}.
+nested_tuple_whole({nested,{ok,X}}) ->
+    {nested,{ok,X}}.
+nested_tuple_with_alias({nested,{ok,_}=Y}) ->
+    {nested,Y}.
+
+tuple_rebinding_after(Y) ->
+    (fun(X) -> {ok,X} end)(Y),
+    case Y of {ok,X} -> {ok,X} end.
+unaliased_tuple_rebinding_before({ok,X}) ->
+    io:format("~p~n", [X]),
+    (fun(X) -> {ok,X} end)(value).
+unaliased_literal_tuple_head({nested,{ok,value}=X}) ->
+    io:format("~p~n", [X]),
+    {nested,{ok,value}}.
+unaliased_literal_tuple_body({nested,{ok,value}=X}) ->
+    Res = {nested,Y={ok,value}},
+    io:format("~p~n", [[X,Y]]),
+    Res.
+unaliased_different_var_tuple({nested,{ok,value}=X}, Y) ->
+    io:format("~p~n", [X]),
+    {nested,Y}.
+
+cons(Config) when is_list(Config) ->
+    Cons = [ok|id(value)],
+
+    true = erts_debug:same(Cons, simple_cons(Cons)),
+    true = erts_debug:same(Cons, simple_cons_in_map(#{hello => Cons})),
+    true = erts_debug:same(Cons, simple_cons_case_repeated(Cons, Cons)),
+    true = erts_debug:same(Cons, simple_cons_fun_repeated(Cons, Cons)),
+    true = erts_debug:same(Cons, simple_cons_twice_head(Cons, Cons)),
+
+    {Cons1,Cons2} = simple_cons_twice_body(Cons),
+    true = erts_debug:same(Cons, Cons1),
+    true = erts_debug:same(Cons, Cons2),
+
+    Nested = [nested,Cons],
+    true = erts_debug:same(Cons, nested_cons_part(Nested)),
+    true = erts_debug:same(Nested, nested_cons_whole(Nested)),
+    true = erts_debug:same(Nested, nested_cons_with_alias(Nested)),
+    true = erts_debug:same(Cons, cons_rebinding_after(Cons)),
+
+    Unstripped = id([a,b]),
+    Stripped = cons_with_binary([<<>>|Unstripped]),
+    true = erts_debug:same(Unstripped, Stripped),
+
+    Cons = unaliased_cons_rebinding_before(Cons),
+    false = erts_debug:same(Cons, unaliased_cons_rebinding_before(Cons)),
+    Nested = unaliased_literal_cons_head(Nested),
+    false = erts_debug:same(Nested, unaliased_literal_cons_head(Nested)),
+    Nested = unaliased_literal_cons_body(Nested),
+    false = erts_debug:same(Nested, unaliased_literal_cons_body(Nested)),
+    Nested = unaliased_different_var_cons(Nested, Cons),
+    false = erts_debug:same(Nested, unaliased_different_var_cons(Nested, Cons)).
+
+simple_cons([ok|X]) ->
+    [ok|X].
+simple_cons_twice_head([ok|X], [ok|X]) ->
+    [ok|X].
+simple_cons_twice_body([ok|X]) ->
+    {[ok|X],[ok|X]}.
+simple_cons_in_map(#{hello := [ok|X]}) ->
+    [ok|X].
+simple_cons_fun_repeated([ok|X], Y) ->
+    io:format("~p~n", [X]),
+    (fun([ok|X]) -> [ok|X] end)(Y).
+simple_cons_case_repeated([ok|X], Y) ->
+    io:format("~p~n", [X]),
+    case Y of [ok|X] -> [ok|X] end.
+
+nested_cons_part([nested,[ok|X]]) ->
+    [ok|X].
+nested_cons_whole([nested,[ok|X]]) ->
+    [nested,[ok|X]].
+nested_cons_with_alias([nested,[ok|_]=Y]) ->
+    [nested,Y].
+
+cons_with_binary([<<>>,X|Y]) ->
+    cons_with_binary([X|Y]);
+cons_with_binary(A) ->
+    A.
+
+cons_rebinding_after(Y) ->
+    (fun(X) -> [ok|X] end)(Y),
+    case Y of [ok|X] -> [ok|X] end.
+unaliased_cons_rebinding_before([ok|X]) ->
+    io:format("~p~n", [X]),
+    (fun(X) -> [ok|X] end)(value).
+unaliased_literal_cons_head([nested,[ok|value]=X]) ->
+    io:format("~p~n", [X]),
+    [nested,[ok|value]].
+unaliased_literal_cons_body([nested,[ok|value]=X]) ->
+    Res = [nested,Y=[ok|value]],
+    io:format("~p~n", [[X, Y]]),
+    Res.
+unaliased_different_var_cons([nested,[ok|value]=X], Y) ->
+    io:format("~p~n", [X]),
+    [nested,Y].
diff --git a/lib/compiler/test/core_fold_SUITE.erl b/lib/compiler/test/core_fold_SUITE.erl
index 0097e28d4d..262967d03d 100644
--- a/lib/compiler/test/core_fold_SUITE.erl
+++ b/lib/compiler/test/core_fold_SUITE.erl
@@ -26,7 +26,8 @@
 	 unused_multiple_values_error/1,unused_multiple_values/1,
 	 multiple_aliases/1,redundant_boolean_clauses/1,
 	 mixed_matching_clauses/1,unnecessary_building/1,
-	 no_no_file/1,configuration/1,supplies/1]).
+	 no_no_file/1,configuration/1,supplies/1,
+         redundant_stack_frame/1]).
 
 -export([foo/0,foo/1,foo/2,foo/3]).
 
@@ -45,7 +46,8 @@ groups() ->
        unused_multiple_values_error,unused_multiple_values,
        multiple_aliases,redundant_boolean_clauses,
        mixed_matching_clauses,unnecessary_building,
-       no_no_file,configuration,supplies]}].
+       no_no_file,configuration,supplies,
+       redundant_stack_frame]}].
 
 
 init_per_suite(Config) ->
@@ -527,4 +529,26 @@ supplies(_Config) ->
 
 do_supplies(#{1 := Value}) when byte_size(Value), byte_size(kg) -> working.
 
+redundant_stack_frame(_Config) ->
+    {1,2} = do_redundant_stack_frame(#{x=>1,y=>2}),
+    {'EXIT',{{badkey,_,x},_}} = (catch do_redundant_stack_frame(#{y=>2})),
+    {'EXIT',{{badkey,_,y},_}} = (catch do_redundant_stack_frame(#{x=>1})),
+    ok.
+
+do_redundant_stack_frame(Map) ->
+    %% There should not be a stack frame for this function.
+    X = case Map of
+            #{x := X0} ->
+                X0;
+            #{} ->
+                erlang:error({badkey, Map, x})
+        end,
+    Y = case Map of
+            #{y := Y0} ->
+                Y0;
+            #{} ->
+                erlang:error({badkey, Map, y})
+        end,
+    {X, Y}.
+
 id(I) -> I.
diff --git a/lib/compiler/test/guard_SUITE.erl b/lib/compiler/test/guard_SUITE.erl
index ccb9b58225..0d6f8c6f98 100644
--- a/lib/compiler/test/guard_SUITE.erl
+++ b/lib/compiler/test/guard_SUITE.erl
@@ -35,7 +35,8 @@
 	 basic_andalso_orelse/1,traverse_dcd/1,
 	 check_qlc_hrl/1,andalso_semi/1,t_tuple_size/1,binary_part/1,
 	 bad_constants/1,bad_guards/1,
-	 guard_in_catch/1,beam_bool_SUITE/1]).
+         guard_in_catch/1,beam_bool_SUITE/1,
+         cover_beam_dead/1]).
 
 suite() -> [{ct_hooks,[ts_install_cth]}].
 
@@ -54,7 +55,8 @@ groups() ->
        rel_ops,rel_op_combinations,
        literal_type_tests,basic_andalso_orelse,traverse_dcd,
        check_qlc_hrl,andalso_semi,t_tuple_size,binary_part,
-       bad_constants,bad_guards,guard_in_catch,beam_bool_SUITE]}].
+       bad_constants,bad_guards,guard_in_catch,beam_bool_SUITE,
+       cover_beam_dead]}].
 
 init_per_suite(Config) ->
     Config.
@@ -1291,6 +1293,10 @@ rel_ops(Config) when is_list(Config) ->
     true = any_atom /= id(42),
     true = [] /= id(42),
 
+    %% Coverage of beam_utils:bif_to_test/3
+    Empty = id([]),
+    ?T(==, [], Empty),
+
     ok.
 
 -undef(TestOp).
@@ -1615,7 +1621,9 @@ type_tests() ->
      is_reference,
      is_port,
      is_binary,
-     is_function].
+     is_bitstring,
+     is_function,
+     is_map].
 
 basic_andalso_orelse(Config) when is_list(Config) ->
     T = id({type,integers,23,42}),
@@ -2198,7 +2206,31 @@ maps() ->
 evidence(#{0 := Charge}) when 0; #{[] => Charge} == #{[] => 42} ->
     ok.
 
+cover_beam_dead(_Config) ->
+    Mod = ?FUNCTION_NAME,
+    Attr = [],
+    Fs = [{function,test,1,2,
+           [{label,1},
+            {line,[]},
+            {func_info,{atom,Mod},{atom,test},1},
+            {label,2},
+            %% Cover beam_dead:turn_op/1 using swapped operand order.
+            {test,is_ne_exact,{f,3},[{integer,1},{x,0}]},
+            {test,is_eq_exact,{f,1},[{atom,a},{x,0}]},
+            {label,3},
+            {move,{atom,ok},{x,0}},
+            return]}],
+    Exp = [{test,1}],
+    Asm = {Mod,Exp,Attr,Fs,3},
+    {ok,Mod,Beam} = compile:forms(Asm, [from_asm,binary,report]),
+    {module,Mod} = code:load_binary(Mod, Mod, Beam),
+    ok = Mod:test(1),
+    ok = Mod:test(a),
+    {'EXIT',_} = (catch Mod:test(other)),
+    true = code:delete(Mod),
+    _ = code:purge(Mod),
 
+    ok.
 
 %% Call this function to turn off constant propagation.
 id(I) -> I.
diff --git a/lib/compiler/test/map_SUITE.erl b/lib/compiler/test/map_SUITE.erl
index 5e90b79aa2..f15917e3cb 100644
--- a/lib/compiler/test/map_SUITE.erl
+++ b/lib/compiler/test/map_SUITE.erl
@@ -695,8 +695,28 @@ t_is_map(Config) when is_list(Config) ->
     if is_map(#{b=>1}) -> ok end,
     if not is_map([1,2,3]) -> ok end,
     if not is_map(x) -> ok end,
+
+    ok = do_t_is_map(map, #{}),
+    error = do_t_is_map(map, {a,b,c}),
+    ok = do_t_is_map(number, 42),
+    ok = do_t_is_map(number, 42.0),
+    error = do_t_is_map(number, {a,b,c}),
     ok.
 
+do_t_is_map(What, X) ->
+    B = case What of
+            map ->
+                %% Cover conversion of is_map/1 BIF to test instruction
+                %% in beam_utils:bif_to_test/3.
+                is_map(X);
+            number ->
+                is_number(X)
+        end,
+    case B of
+        true -> ok;
+        false -> error
+    end.
+
 % test map updates without matching
 t_update_literals(Config) when is_list(Config) ->
     Map = #{x=>1,y=>2,z=>3,q=>4},
diff --git a/lib/compiler/test/match_SUITE.erl b/lib/compiler/test/match_SUITE.erl
index 52b2da05f7..4b26a8dcdc 100644
--- a/lib/compiler/test/match_SUITE.erl
+++ b/lib/compiler/test/match_SUITE.erl
@@ -23,8 +23,9 @@
 	 init_per_group/2,end_per_group/2,
 	 pmatch/1,mixed/1,aliases/1,non_matching_aliases/1,
 	 match_in_call/1,untuplify/1,shortcut_boolean/1,letify_guard/1,
-	 selectify/1,underscore/1,match_map/1,map_vars_used/1,
-	 coverage/1,grab_bag/1,literal_binary/1]).
+	 selectify/1,deselectify/1,underscore/1,match_map/1,map_vars_used/1,
+	 coverage/1,grab_bag/1,literal_binary/1,
+         unary_op/1]).
 	 
 -include_lib("common_test/include/ct.hrl").
 
@@ -38,9 +39,9 @@ groups() ->
     [{p,[parallel],
       [pmatch,mixed,aliases,non_matching_aliases,
        match_in_call,untuplify,
-       shortcut_boolean,letify_guard,selectify,
+       shortcut_boolean,letify_guard,selectify,deselectify,
        underscore,match_map,map_vars_used,coverage,
-       grab_bag,literal_binary]}].
+       grab_bag,literal_binary,unary_op]}].
 
 
 init_per_suite(Config) ->
@@ -466,6 +467,66 @@ sel_same_value2(V) when V =:= 42; V =:= 43 ->
 sel_same_value2(_) ->
     error.
 
+%% Test deconstruction of select_val instructions in beam_peep into
+%% regular tests with just one possible value left. Hitting proper cases
+%% in beam_peep relies on unification of labels by beam_jump.
+
+deselectify(Config) when is_list(Config) ->
+    one_or_other = desel_tuple_arity({1}),
+    two = desel_tuple_arity({1,1}),
+    one_or_other = desel_tuple_arity({1,1,1}),
+
+    one_or_other = dsel_integer(1),
+    two = dsel_integer(2),
+    one_or_other = dsel_integer(3),
+
+    one_or_other = dsel_integer_typecheck(1),
+    two = dsel_integer_typecheck(2),
+    one_or_other = dsel_integer_typecheck(3),
+
+    one_or_other = dsel_atom(one),
+    two = dsel_atom(two),
+    one_or_other = dsel_atom(three),
+
+    one_or_other = dsel_atom_typecheck(one),
+    two = dsel_atom_typecheck(two),
+    one_or_other = dsel_atom_typecheck(three).
+
+desel_tuple_arity(Tuple) when is_tuple(Tuple) ->
+    case Tuple of
+        {_} -> one_or_other;
+        {_,_} -> two;
+        _ -> one_or_other
+    end.
+
+dsel_integer(Val) ->
+    case Val of
+        1 -> one_or_other;
+        2 -> two;
+        _ -> one_or_other
+    end.
+
+dsel_integer_typecheck(Val) when is_integer(Val) ->
+    case Val of
+        1 -> one_or_other;
+        2 -> two;
+        _ -> one_or_other
+    end.
+
+dsel_atom(Val) ->
+    case Val of
+        one -> one_or_other;
+        two -> two;
+        _ -> one_or_other
+    end.
+
+dsel_atom_typecheck(Val) when is_atom(Val) ->
+    case Val of
+        one -> one_or_other;
+        two -> two;
+        _ -> one_or_other
+    end.
+
 underscore(Config) when is_list(Config) ->
     case Config of
 	[] ->
@@ -557,6 +618,10 @@ grab_bag(_Config) ->
 	 {bad,16#555555555555555555555555555555555555555555555555555}],
     ok = grab_bag_remove_failure(L, unit, 0),
 
+    {42,<<43,44>>} = grab_bag_single_valued(<<42,43,44>>),
+    empty_list = grab_bag_single_valued([]),
+    empty_tuple = grab_bag_single_valued({}),
+
     ok.
 
 grab_bag_remove_failure([], _Unit, _MaxFailure) ->
@@ -574,6 +639,12 @@ grab_bag_remove_failure([{stretch,_,Mi}=Stretch | Specs], Unit, _MaxFailure) ->
 	    ok
     end.
 
+%% Cover a line v3_kernel that places binary matching first.
+grab_bag_single_valued(<<H,T/bytes>>) -> {H,T};
+grab_bag_single_valued([]) -> empty_list;
+grab_bag_single_valued({}) -> empty_tuple.
+
+
 %% Regression in 19.0, reported by Alexei Sholik
 literal_binary(_Config) ->
     3 = literal_binary_match(bar, <<"y">>),
@@ -592,5 +663,74 @@ literal_binary_match(_, <<"x">>) -> 2;
 literal_binary_match(_, <<"y">>) -> 3;
 literal_binary_match(_, _) -> fail.
 
+unary_op(Config) ->
+    %% ERL-514. This test case only verifies that the code
+    %% calculates the correct result, not that the generated
+    %% code is optimial.
+
+    {non_associative,30} = unary_op_1('&'),
+    {non_associative,300} = unary_op_1('^'),
+    {non_associative,300} = unary_op_1('not'),
+    {non_associative,300} = unary_op_1('+'),
+    {non_associative,300} = unary_op_1('-'),
+    {non_associative,300} = unary_op_1('~~~'),
+    {non_associative,300} = unary_op_1('!'),
+    {non_associative,320} = unary_op_1('@'),
+
+    error = unary_op_1(Config),
+    error = unary_op_1(abc),
+    error = unary_op_1(42),
+
+    ok.
+
+unary_op_1(Vop@1) ->
+    %% If all optimizations are working as they should, there should
+    %% be no stack frame and all '=:=' tests should be coalesced into
+    %% a single select_val instruction.
+
+    case Vop@1 =:= '&' of
+        true ->
+            {non_associative,30};
+        false ->
+            case
+                case Vop@1 =:= '^' of
+                    true ->
+                        true;
+                    false ->
+                        case Vop@1 =:= 'not' of
+                            true ->
+                                true;
+                            false ->
+                                case Vop@1 =:= '+' of
+                                    true ->
+                                        true;
+                                    false ->
+                                        case Vop@1 =:= '-' of
+                                            true ->
+                                                true;
+                                            false ->
+                                                case Vop@1 =:= '~~~' of
+                                                    true ->
+                                                        true;
+                                                    false ->
+                                                        Vop@1 =:= '!'
+                                                end
+                                        end
+                                end
+                        end
+                end
+            of
+                true ->
+                    {non_associative,300};
+                false ->
+                    case Vop@1 =:= '@' of
+                        true ->
+                            {non_associative,320};
+                        false ->
+                            error
+                    end
+            end
+    end.
+
 
 id(I) -> I.
diff --git a/lib/compiler/test/misc_SUITE.erl b/lib/compiler/test/misc_SUITE.erl
index 4bd884d86b..d93c5dda1e 100644
--- a/lib/compiler/test/misc_SUITE.erl
+++ b/lib/compiler/test/misc_SUITE.erl
@@ -161,16 +161,17 @@ md5_1(Beam) ->
 %% Cover some code that handles internal errors.
 
 silly_coverage(Config) when is_list(Config) ->
-    %% sys_core_fold, sys_core_bsm, sys_core_setel, v3_kernel
+    %% sys_core_fold, sys_core_alias, sys_core_bsm, sys_core_setel, v3_kernel
     BadCoreErlang = {c_module,[],
 		     name,[],[],
 		     [{{c_var,[],{foo,2}},seriously_bad_body}]},
     expect_error(fun() -> sys_core_fold:module(BadCoreErlang, []) end),
+    expect_error(fun() -> sys_core_alias:module(BadCoreErlang, []) end),
     expect_error(fun() -> sys_core_bsm:module(BadCoreErlang, []) end),
     expect_error(fun() -> sys_core_dsetel:module(BadCoreErlang, []) end),
     expect_error(fun() -> v3_kernel:module(BadCoreErlang, []) end),
 
-    %% v3_life
+    %% v3_codegen
     BadKernel = {k_mdef,[],?MODULE,
 		 [{foo,0}],
 		 [],
@@ -178,11 +179,7 @@ silly_coverage(Config) when is_list(Config) ->
 		   {k,[],[],[]},
 		   f,0,[],
 		   seriously_bad_body}]},
-    expect_error(fun() -> v3_life:module(BadKernel, []) end),
-
-    %% v3_codegen
-    CodegenInput = {?MODULE,[{foo,0}],[],[{function,foo,0,[a|b],a,b,[]}]},
-    expect_error(fun() -> v3_codegen:module(CodegenInput, []) end),
+    expect_error(fun() -> v3_codegen:module(BadKernel, []) end),
 
     %% beam_a
     BeamAInput = {?MODULE,[{foo,0}],[],
@@ -321,8 +318,7 @@ expect_error(Fun) ->
 	    io:format("~p", [Any]),
 	    ct:fail(call_was_supposed_to_fail)
     catch
-	Class:Reason ->
-	    Stk = erlang:get_stacktrace(),
+	Class:Reason:Stk ->
 	    io:format("~p:~p\n~p\n", [Class,Reason,Stk]),
 	    case {Class,Reason} of
 		{error,undef} ->
diff --git a/lib/compiler/test/receive_SUITE.erl b/lib/compiler/test/receive_SUITE.erl
index 8304672558..5e386790c0 100644
--- a/lib/compiler/test/receive_SUITE.erl
+++ b/lib/compiler/test/receive_SUITE.erl
@@ -222,9 +222,8 @@ do_ref_opt(Source, PrivDir) ->
 		    collect_recv_opt_instrs(Code)
 	end,
 	ok
-    catch Class:Error ->
-	    io:format("~s: ~p ~p\n~p\n",
-		      [Source,Class,Error,erlang:get_stacktrace()]),
+    catch Class:Error:Stk ->
+	    io:format("~s: ~p ~p\n~p\n", [Source,Class,Error,Stk]),
 	    error
     end.
 
@@ -265,6 +264,10 @@ export(Config) when is_list(Config) ->
     self() ! {result,Ref,42},
     42 = export_1(Ref),
     {error,timeout} = export_1(Ref),
+
+    self() ! {result,Ref},
+    {ok,Ref} = export_2(),
+
     ok.
 
 export_1(Reference) ->
@@ -281,6 +284,10 @@ export_1(Reference) ->
     id({build,self()}),
     Result.
 
+export_2() ->
+    receive {result,Result} -> ok end,
+    {ok,Result}.
+
 wait(Config) when is_list(Config) ->
     self() ! <<42>>,
     <<42>> = wait_1(r, 1, 2),
diff --git a/lib/compiler/test/trycatch_SUITE.erl b/lib/compiler/test/trycatch_SUITE.erl
index a591d6cc93..8cf7928cc4 100644
--- a/lib/compiler/test/trycatch_SUITE.erl
+++ b/lib/compiler/test/trycatch_SUITE.erl
@@ -26,7 +26,8 @@
 	 nested_of/1,nested_catch/1,nested_after/1,
 	 nested_horrid/1,last_call_optimization/1,bool/1,
 	 plain_catch_coverage/1,andalso_orelse/1,get_in_try/1,
-	 hockey/1,handle_info/1,catch_in_catch/1,grab_bag/1]).
+	 hockey/1,handle_info/1,catch_in_catch/1,grab_bag/1,
+         stacktrace/1,nested_stacktrace/1]).
 
 -include_lib("common_test/include/ct.hrl").
 
@@ -42,7 +43,8 @@ groups() ->
        after_oops,eclectic,rethrow,nested_of,nested_catch,
        nested_after,nested_horrid,last_call_optimization,
        bool,plain_catch_coverage,andalso_orelse,get_in_try,
-       hockey,handle_info,catch_in_catch,grab_bag]}].
+       hockey,handle_info,catch_in_catch,grab_bag,
+       stacktrace,nested_stacktrace]}].
 
 
 init_per_suite(Config) ->
@@ -324,11 +326,11 @@ eclectic(Conf) when is_list(Conf) ->
     {{error,{exit,V},{'EXIT',V}},V} =
 	eclectic_1({foo,{error,{exit,V}}}, error, {value,V}),
     {{value,{value,V},V},
-	   {'EXIT',{badarith,[{?MODULE,my_add,2,_}|_]}}} =
+	   {'EXIT',{badarith,[{erlang,'+',[0,a],_},{?MODULE,my_add,2,_}|_]}}} =
 	eclectic_1({foo,{value,{value,V}}}, undefined, {'add',{0,a}}),
     {{'EXIT',V},V} =
 	eclectic_1({catch_foo,{exit,V}}, undefined, {throw,V}),
-    {{error,{'div',{1,0}},{'EXIT',{badarith,[{?MODULE,my_div,2,_}|_]}}},
+    {{error,{'div',{1,0}},{'EXIT',{badarith,[{erlang,'div',[1,0],_},{?MODULE,my_div,2,_}|_]}}},
 	   {'EXIT',V}} =
 	eclectic_1({foo,{error,{'div',{1,0}}}}, error, {exit,V}),
     {{{error,V},{'EXIT',{V,[{?MODULE,foo,1,_}|_]}}},
@@ -345,7 +347,7 @@ eclectic(Conf) when is_list(Conf) ->
 	eclectic_2({error,{value,V}}, throw, {error,V}),
     {{caught,{'EXIT',{badarg,[{erlang,abs,[V],_}|_]}}},V} =
 	eclectic_2({value,{'abs',V}}, undefined, {value,V}),
-    {{caught,{'EXIT',{badarith,[{?MODULE,my_add,2,_}|_]}}},V} =
+    {{caught,{'EXIT',{badarith,[{erlang,'+',[0,a],_},{?MODULE,my_add,2,_}|_]}}},V} =
 	eclectic_2({exit,{'add',{0,a}}}, exit, {value,V}),
     {{caught,{'EXIT',V}},undefined} =
 	eclectic_2({value,{error,V}}, undefined, {exit,V}),
@@ -1039,5 +1041,123 @@ grab_bag(_Config) ->
 
     ok.
 
+stacktrace(_Config) ->
+    V = [make_ref()|self()],
+    case ?MODULE:module_info(native) of
+        false ->
+            {value2,{caught1,badarg,[{erlang,abs,[V],_}|_]}} =
+                stacktrace_1({'abs',V}, error, {value,V}),
+            {caught2,{error,badarith},[{erlang,'+',[0,a],_},
+                                       {?MODULE,my_add,2,_}|_]} =
+                stacktrace_1({'div',{1,0}}, error, {'add',{0,a}});
+        true ->
+            {value2,{caught1,badarg,[{?MODULE,my_abs,1,_}|_]}} =
+                stacktrace_1({'abs',V}, error, {value,V}),
+            {caught2,{error,badarith},[{?MODULE,my_add,2,_}|_]} =
+                stacktrace_1({'div',{1,0}}, error, {'add',{0,a}})
+    end,
+    {caught2,{error,{try_clause,V}},[{?MODULE,stacktrace_1,3,_}|_]} =
+        stacktrace_1({value,V}, error, {value,V}),
+    {caught2,{throw,V},[{?MODULE,foo,1,_}|_]} =
+        stacktrace_1({value,V}, error, {throw,V}),
+
+    try
+        stacktrace_2()
+    catch
+        error:{badmatch,_}:Stk2 ->
+            [{?MODULE,stacktrace_2,0,_},
+             {?MODULE,stacktrace,1,_}|_] = Stk2,
+            Stk2 = erlang:get_stacktrace(),
+            ok
+    end,
+
+    try
+        stacktrace_3(a, b)
+    catch
+        error:function_clause:Stk3 ->
+            Stk3 = erlang:get_stacktrace(),
+            case lists:module_info(native) of
+                false ->
+                    [{lists,prefix,[a,b],_}|_] = Stk3;
+                true ->
+                    [{lists,prefix,2,_}|_] = Stk3
+            end
+    end,
+
+    try
+        throw(x)
+    catch
+        throw:x:IntentionallyUnused ->
+            ok
+    end.
+
+stacktrace_1(X, C1, Y) ->
+    try try foo(X) of
+            C1 -> value1
+        catch
+            C1:D1:Stk1 ->
+                Stk1 = erlang:get_stacktrace(),
+                {caught1,D1,Stk1}
+        after
+            foo(Y)
+        end of
+        V2 -> {value2,V2}
+    catch
+        C2:D2:Stk2 -> {caught2,{C2,D2},Stk2=erlang:get_stacktrace()}
+    end.
+
+stacktrace_2() ->
+    ok = erlang:process_info(self(), current_function),
+    ok.
+
+stacktrace_3(A, B) ->
+    {ok,lists:prefix(A, B)}.
+
+nested_stacktrace(_Config) ->
+    V = [{make_ref()}|[self()]],
+    value1 = nested_stacktrace_1({{value,{V,x1}},void,{V,x1}},
+                                 {void,void,void}),
+    case ?MODULE:module_info(native) of
+        false ->
+            {caught1,
+             [{erlang,'+',[V,x1],_},{?MODULE,my_add,2,_}|_],
+             value2} =
+                nested_stacktrace_1({{'add',{V,x1}},error,badarith},
+                                    {{value,{V,x2}},void,{V,x2}}),
+            {caught1,
+             [{erlang,'+',[V,x1],_},{?MODULE,my_add,2,_}|_],
+             {caught2,[{erlang,abs,[V],_}|_]}} =
+                nested_stacktrace_1({{'add',{V,x1}},error,badarith},
+                                    {{'abs',V},error,badarg});
+        true ->
+            {caught1,
+             [{?MODULE,my_add,2,_}|_],
+             value2} =
+                nested_stacktrace_1({{'add',{V,x1}},error,badarith},
+                                    {{value,{V,x2}},void,{V,x2}}),
+            {caught1,
+             [{?MODULE,my_add,2,_}|_],
+             {caught2,[{?MODULE,my_abs,1,_}|_]}} =
+                nested_stacktrace_1({{'add',{V,x1}},error,badarith},
+                                    {{'abs',V},error,badarg})
+    end,
+    ok.
+
+nested_stacktrace_1({X1,C1,V1}, {X2,C2,V2}) ->
+    try foo(X1) of
+        V1 -> value1
+    catch
+        C1:V1:S1 ->
+            S1 = erlang:get_stacktrace(),
+            T2 = try foo(X2) of
+                     V2 -> value2
+                 catch
+                     C2:V2:S2 ->
+                         S2 = erlang:get_stacktrace(),
+                         {caught2,S2}
+                 end,
+            {caught1,S1,T2}
+    end.
+
 
 id(I) -> I.
diff --git a/lib/compiler/test/z_SUITE.erl b/lib/compiler/test/z_SUITE.erl
index d864184f4c..cd95d0e733 100644
--- a/lib/compiler/test/z_SUITE.erl
+++ b/lib/compiler/test/z_SUITE.erl
@@ -54,8 +54,7 @@ do_loaded([{M,_}|Ms], E0) ->
 	    _ = M:module_info(functions),
 	    E0
 	catch
-	    C:Error ->
-		Stk = erlang:get_stacktrace(),
+	    C:Error:Stk ->
 		io:format("~p:~p\n~p\n", [C,Error,Stk]),
 		E0 + 1
 	end,
diff --git a/lib/crypto/doc/src/crypto.xml b/lib/crypto/doc/src/crypto.xml
index 464799b320..3a5efd0bea 100644
--- a/lib/crypto/doc/src/crypto.xml
+++ b/lib/crypto/doc/src/crypto.xml
@@ -790,9 +790,16 @@
 	  <seealso marker="stdlib:rand">random number generation</seealso>,
           in order to generate cryptographically strong random numbers
           (based on OpenSSL's <c>BN_rand_range</c>),
-          and saves it on process dictionary before returning it as well.
+          and saves it in the process dictionary before returning it as well.
           See also
-	  <seealso marker="stdlib:rand#seed-1">rand:seed/1</seealso>.
+	  <seealso marker="stdlib:rand#seed-1">rand:seed/1</seealso> and
+	  <seealso marker="#rand_seed_s-0">rand_seed_s/0</seealso>.
+	</p>
+	<p>
+	  When using the state object from this function the 
+	  <seealso marker="stdlib:rand">rand</seealso> functions using it
+	  may throw exception <c>low_entropy</c> in case the random generator
+	  failed due to lack of secure "randomness".
 	</p>
         <p><em>Example</em></p>
         <pre>
@@ -814,6 +821,120 @@ _FloatValue = rand:uniform().     % [0.0; 1.0[</pre>
           See also
 	  <seealso marker="stdlib:rand#seed_s-1">rand:seed_s/1</seealso>.
 	</p>
+	<p>
+	  When using the state object from this function the 
+	  <seealso marker="stdlib:rand">rand</seealso> functions using it
+	  may throw exception <c>low_entropy</c> in case the random generator
+	  failed due to lack of secure "randomness".
+	</p>
+	<note>
+	  <p>
+	    The state returned from this function can not be used
+	    to get a reproducable random sequence as from
+	    the other 
+	    <seealso marker="stdlib:rand">rand</seealso>
+	    functions,
+	    since reproducability does not match cryptographically safe.
+	  </p>
+	  <p>
+	    The only supported usage is to generate one distinct
+	    random sequence from this start state.
+	  </p>
+	</note>
+      </desc>
+    </func>
+
+    <func>
+      <name>rand_seed_alg(Alg) -> rand:state()</name>
+      <fsummary>Strong random number generation plugin state</fsummary>
+      <type>
+        <v>Alg = crypto | crypto_cache</v>
+      </type>
+      <desc>
+	<marker id="rand_seed_alg-1" />
+	<p>
+          Creates state object for
+	  <seealso marker="stdlib:rand">random number generation</seealso>,
+          in order to generate cryptographically strong random numbers.
+          See also
+	  <seealso marker="stdlib:rand#seed-1">rand:seed/1</seealso> and
+	  <seealso marker="#rand_seed_alg_s-1">rand_seed_alg_s/1</seealso>.
+	</p>
+	<p>
+	  When using the state object from this function the 
+	  <seealso marker="stdlib:rand">rand</seealso> functions using it
+	  may throw exception <c>low_entropy</c> in case the random generator
+	  failed due to lack of secure "randomness".
+	</p>
+	<p>
+	  The cache size can be changed from its default value using the
+	  <seealso marker="crypto_app">
+	    crypto app's
+	  </seealso> configuration parameter <c>rand_cache_size</c>.
+	</p>
+        <p><em>Example</em></p>
+        <pre>
+_ = crypto:rand_seed_alg(crypto_cache),
+_IntegerValue = rand:uniform(42), % [1; 42]
+_FloatValue = rand:uniform().     % [0.0; 1.0[</pre>
+      </desc>
+    </func>
+
+    <func>
+      <name>rand_seed_alg_s(Alg) -> rand:state()</name>
+      <fsummary>Strong random number generation plugin state</fsummary>
+      <type>
+        <v>Alg = crypto | crypto_cache</v>
+      </type>
+      <desc>
+	<marker id="rand_seed_alg_s-1" />
+	<p>
+          Creates state object for
+	  <seealso marker="stdlib:rand">random number generation</seealso>,
+          in order to generate cryptographically strongly random numbers.
+          See also
+	  <seealso marker="stdlib:rand#seed_s-1">rand:seed_s/1</seealso>.
+	</p>
+	<p>
+	  If <c>Alg</c> is <c>crypto</c> this function behaves exactly like
+	  <seealso marker="#rand_seed_s-0">rand_seed_s/0</seealso>.
+	</p>
+	<p>
+	  If <c>Alg</c> is <c>crypto_cache</c> this function
+	  fetches random data with OpenSSL's <c>RAND_bytes</c>
+	  and caches it for speed using an internal word size
+	  of 56 bits that makes calculations fast on 64 bit machines.
+	</p>
+	<p>
+	  When using the state object from this function the 
+	  <seealso marker="stdlib:rand">rand</seealso> functions using it
+	  may throw exception <c>low_entropy</c> in case the random generator
+	  failed due to lack of secure "randomness".
+	</p>
+	<p>
+	  The cache size can be changed from its default value using the
+	  <seealso marker="crypto_app">
+	    crypto app's
+	  </seealso> configuration parameter <c>rand_cache_size</c>.
+	</p>
+	<note>
+	  <p>
+	    The state returned from this function can not be used
+	    to get a reproducable random sequence as from
+	    the other 
+	    <seealso marker="stdlib:rand">rand</seealso>
+	    functions,
+	    since reproducability does not match cryptographically safe.
+	  </p>
+	  <p>
+	    In fact since random data is cached some numbers may
+	    get reproduced if you try, but this is unpredictable.
+	  </p>
+	  <p>
+	    The only supported usage is to generate one distinct
+	    random sequence from this start state.
+	  </p>
+	</note>
       </desc>
     </func>
 
diff --git a/lib/crypto/doc/src/crypto_app.xml b/lib/crypto/doc/src/crypto_app.xml
index ba22557480..8296b1bc77 100644
--- a/lib/crypto/doc/src/crypto_app.xml
+++ b/lib/crypto/doc/src/crypto_app.xml
@@ -68,6 +68,24 @@
         thus the crypto module will fail to load. This mechanism
         prevents the accidental use of non-validated algorithms.</p>
       </item>
+      <tag><c>rand_cache_size = integer()</c></tag>
+      <item>
+        <p>
+	  Sets the cache size in bytes to use by
+	  <seealso marker="crypto#rand_seed_alg-1">
+	    <c>crypto:rand_seed_alg(crypto_cache)</c>
+	  </seealso> and
+	  <seealso marker="crypto#rand_seed_alg_s-1">
+	    <c>crypto:rand_seed_alg_s(crypto_cache)</c>
+	  </seealso>.
+	  This parameter is read when a seed function is called,
+	  and then kept in generators state object.  It has a rather
+	  small default value that causes reads of strong random bytes
+	  about once per hundred calls for a random value.
+	  The set value is rounded up to an integral number of words
+	  of the size these seed functions use.
+	</p>
+      </item>
     </taglist>
   </section>
 
diff --git a/lib/crypto/src/crypto.app.src b/lib/crypto/src/crypto.app.src
index 1d3f35e465..492aa10e51 100644
--- a/lib/crypto/src/crypto.app.src
+++ b/lib/crypto/src/crypto.app.src
@@ -24,7 +24,7 @@
 	       crypto_ec_curves]},
     {registered, []},
     {applications, [kernel, stdlib]},
-    {env, [{fips_mode, false}]},
+    {env, [{fips_mode, false}, {rand_cache_size, 896}]},
     {runtime_dependencies, ["erts-9.0","stdlib-3.4","kernel-5.3"]}]}.
 
 
diff --git a/lib/crypto/src/crypto.erl b/lib/crypto/src/crypto.erl
index 1a1b4f98b5..df259d5419 100644
--- a/lib/crypto/src/crypto.erl
+++ b/lib/crypto/src/crypto.erl
@@ -30,11 +30,12 @@
 -export([hmac/3, hmac/4, hmac_init/2, hmac_update/2, hmac_final/1, hmac_final_n/2]).
 -export([cmac/3, cmac/4]).
 -export([exor/2, strong_rand_bytes/1, mod_pow/3]).
--export([rand_seed/0]).
--export([rand_seed_s/0]).
+-export([rand_seed/0, rand_seed_alg/1]).
+-export([rand_seed_s/0, rand_seed_alg_s/1]).
 -export([rand_plugin_next/1]).
 -export([rand_plugin_uniform/1]).
 -export([rand_plugin_uniform/2]).
+-export([rand_cache_plugin_next/1]).
 -export([rand_uniform/2]).
 -export([block_encrypt/3, block_decrypt/3, block_encrypt/4, block_decrypt/4]).
 -export([next_iv/2, next_iv/3]).
@@ -317,9 +318,17 @@ stream_decrypt(State, Data0) ->
 %%
 %% RAND - pseudo random numbers using RN_ and BN_ functions in crypto lib
 %%
+-type rand_cache_seed() ::
+        nonempty_improper_list(non_neg_integer(), binary()).
 -spec strong_rand_bytes(non_neg_integer()) -> binary().
 -spec rand_seed() -> rand:state().
 -spec rand_seed_s() -> rand:state().
+-spec rand_seed_alg(Alg :: atom()) ->
+                           {rand:alg_handler(),
+                            atom() | rand_cache_seed()}.
+-spec rand_seed_alg_s(Alg :: atom()) ->
+                             {rand:alg_handler(),
+                              atom() | rand_cache_seed()}.
 -spec rand_uniform(crypto_integer(), crypto_integer()) ->
 			  crypto_integer().
 
@@ -335,12 +344,36 @@ rand_seed() ->
     rand:seed(rand_seed_s()).
 
 rand_seed_s() ->
+    rand_seed_alg_s(?MODULE).
+
+rand_seed_alg(Alg) ->
+    rand:seed(rand_seed_alg_s(Alg)).
+
+-define(CRYPTO_CACHE_BITS, 56).
+rand_seed_alg_s(?MODULE) ->
     {#{ type => ?MODULE,
         bits => 64,
         next => fun ?MODULE:rand_plugin_next/1,
         uniform => fun ?MODULE:rand_plugin_uniform/1,
         uniform_n => fun ?MODULE:rand_plugin_uniform/2},
-     no_seed}.
+     no_seed};
+rand_seed_alg_s(crypto_cache) ->
+    CacheBits = ?CRYPTO_CACHE_BITS,
+    EnvCacheSize =
+        application:get_env(
+          crypto, rand_cache_size, CacheBits * 16), % Cache 16 * 8 words
+    Bytes = (CacheBits + 7) div 8,
+    CacheSize =
+        case ((EnvCacheSize + (Bytes - 1)) div Bytes) * Bytes of
+            Sz when is_integer(Sz), Bytes =< Sz ->
+                Sz;
+            _ ->
+                Bytes
+        end,
+    {#{ type => crypto_cache,
+        bits => CacheBits,
+        next => fun ?MODULE:rand_cache_plugin_next/1},
+     {CacheBits, CacheSize, <<>>}}.
 
 rand_plugin_next(Seed) ->
     {bytes_to_integer(strong_rand_range(1 bsl 64)), Seed}.
@@ -351,6 +384,12 @@ rand_plugin_uniform(State) ->
 rand_plugin_uniform(Max, State) ->
     {bytes_to_integer(strong_rand_range(Max)) + 1, State}.
 
+rand_cache_plugin_next({CacheBits, CacheSize, <<>>}) ->
+    rand_cache_plugin_next(
+      {CacheBits, CacheSize, strong_rand_bytes(CacheSize)});
+rand_cache_plugin_next({CacheBits, CacheSize, Cache}) ->
+    <<I:CacheBits, NewCache/binary>> = Cache,
+    {I, {CacheBits, CacheSize, NewCache}}.
 
 strong_rand_range(Range) when is_integer(Range), Range > 0 ->
     BinRange = int_to_bin(Range),
@@ -398,7 +437,7 @@ rand_uniform_nif(_From,_To) -> ?nif_stub.
 
 
 -spec rand_seed(binary()) -> ok.
-rand_seed(Seed) ->
+rand_seed(Seed) when is_binary(Seed) ->
     rand_seed_nif(Seed).
 
 rand_seed_nif(_Seed) -> ?nif_stub.
diff --git a/lib/debugger/src/i.erl b/lib/debugger/src/i.erl
index 62ce8d0e20..853fa529a0 100644
--- a/lib/debugger/src/i.erl
+++ b/lib/debugger/src/i.erl
@@ -30,7 +30,7 @@
 -import(lists, [sort/1,foreach/2]).
 
 iv() ->
-    Vsn = string:substr(filename:basename(code:lib_dir(debugger)), 10),
+    Vsn = string:slice(filename:basename(code:lib_dir(debugger)), 9),
     list_to_atom(Vsn).
 
 %% -------------------------------------------
diff --git a/lib/debugger/test/guard_SUITE.erl b/lib/debugger/test/guard_SUITE.erl
index f7874f79df..e781ea932f 100644
--- a/lib/debugger/test/guard_SUITE.erl
+++ b/lib/debugger/test/guard_SUITE.erl
@@ -390,7 +390,7 @@ all_types() ->
      {atom, xxxx},
      {ref, make_ref()},
      {pid, self()},
-     {port, open_port({spawn, efile}, [])},
+     {port, make_port()},
      {function, fun(X) -> X+1, "" end},
      {binary, list_to_binary([])}].
 
@@ -435,6 +435,9 @@ type_test(binary, X) when binary(X) ->
 type_test(function, X) when function(X) ->
     function.
 
+make_port() ->
+    hd(erlang:ports()).
+
 const_guard(Config) when is_list(Config) ->
     if
 	(0 == 0) and ((0 == 0) or (0 == 0)) ->
diff --git a/lib/dialyzer/src/dialyzer_cl.erl b/lib/dialyzer/src/dialyzer_cl.erl
index 0617be6435..1e06d6e974 100644
--- a/lib/dialyzer/src/dialyzer_cl.erl
+++ b/lib/dialyzer/src/dialyzer_cl.erl
@@ -672,7 +672,7 @@ failed_anal_msg(Reason, LogCache) ->
 %%
 format_log_cache(LogCache) ->
   Str = lists:append(lists:reverse(LogCache)),
-  string:join(string:tokens(Str, "\n"), "\n  ").
+  lists:join("\n  ", string:lexemes(Str, "\n")).
 
 -spec store_warnings(#cl_state{}, [raw_warning()]) -> #cl_state{}.
 
diff --git a/lib/dialyzer/src/dialyzer_dataflow.erl b/lib/dialyzer/src/dialyzer_dataflow.erl
index 8367432ac5..93cfea3c5e 100644
--- a/lib/dialyzer/src/dialyzer_dataflow.erl
+++ b/lib/dialyzer/src/dialyzer_dataflow.erl
@@ -299,6 +299,7 @@ traverse(Tree, Map, State) ->
 	  match_fail -> t_none();
 	  raise -> t_none();
 	  bs_init_writable -> t_from_term(<<>>);
+          build_stacktrace -> t_list();
 	  Other -> erlang:error({'Unsupported primop', Other})
 	end,
       {State, Map, Type};
diff --git a/lib/dialyzer/src/dialyzer_gui_wx.erl b/lib/dialyzer/src/dialyzer_gui_wx.erl
index b4b1872c12..b8414b7d8b 100644
--- a/lib/dialyzer/src/dialyzer_gui_wx.erl
+++ b/lib/dialyzer/src/dialyzer_gui_wx.erl
@@ -475,7 +475,7 @@ gui_loop(#gui_state{backend_pid = BackendPid, doc_plt = DocPlt,
       gui_loop(State);
     {BackendPid, ext_types, ExtTypes} ->
       Map = fun({M,F,A}) -> io_lib:format("~tp:~tp/~p",[M,F,A]) end,
-      ExtTypeString = string:join(lists:map(Map, ExtTypes), "\n"),
+      ExtTypeString = lists:join("\n", lists:map(Map, ExtTypes)),
       Msg = io_lib:format("The following remote types are being used "
 			  "but information about them is not available.\n"
 			  "The analysis might get more precise by including "
@@ -638,7 +638,7 @@ output_sms(#gui_state{frame = Frame}, Title, Message, Type) ->
 
 free_editor(#gui_state{gui = Wx, frame = Frame}, Title, Contents0) ->
   Contents = lists:flatten(Contents0),
-  Tokens = string:tokens(Contents, "\n"),
+  Tokens = string:lexemes(Contents, "\n"),
   NofLines = length(Tokens),
   LongestLine = lists:max([length(X) || X <- Tokens]),
   Height0 = NofLines * 25 + 80,
diff --git a/lib/dialyzer/src/dialyzer_races.erl b/lib/dialyzer/src/dialyzer_races.erl
index 7fe64c3e11..7602faa21d 100644
--- a/lib/dialyzer/src/dialyzer_races.erl
+++ b/lib/dialyzer/src/dialyzer_races.erl
@@ -1270,8 +1270,8 @@ filter_named_tables(NamesList) ->
     [] -> [];
     [Head|Tail] ->
       NewHead =
-        case string:rstr(Head, "()") of
-          0 -> [Head];
+        case string:find(Head, "()", trailing) of
+          nomatch -> [Head];
           _Other -> []
         end,
       NewHead ++ filter_named_tables(Tail)
@@ -1558,8 +1558,8 @@ any_args(StrList) ->
   case StrList of
     [] -> false;
     [Head|Tail] ->
-      case string:rstr(Head, "()") of
-        0 -> any_args(Tail);
+      case string:find(Head, "()", trailing) of
+        nomatch -> any_args(Tail);
         _Other -> true
       end
   end.
@@ -1765,10 +1765,8 @@ ets_list_args(MaybeList) ->
   end.
 
 ets_list_argtypes(ListStr) ->
-  ListStr1 = string:strip(ListStr, left, $[),
-  ListStr2 = string:strip(ListStr1, right, $]),
-  ListStr3 = string:strip(ListStr2, right, $.),
-  string:strip(ListStr3, right, $,).
+  ListStr1 = string:trim(ListStr, leading, "$["),
+  string:trim(ListStr1, trailing, "$]$.$,").
 
 ets_tuple_args(MaybeTuple) ->
   case is_tuple(MaybeTuple) of
@@ -1810,7 +1808,7 @@ ets_tuple_argtypes2_helper(TupleStr, ElemStr, NestingLevel) ->
             {[H|ElemStr], NestingLevel, false}
         end,
       case Return of
-        true -> string:tokens(NewElemStr, " |");
+        true -> string:lexemes(NewElemStr, " |");
         false ->
           ets_tuple_argtypes2_helper(T, NewElemStr, NewNestingLevel)
       end
@@ -1889,44 +1887,44 @@ format_args_2(StrArgList, Call) ->
   case Call of
     whereis ->
       lists_key_replace(2, StrArgList,
-	string:tokens(lists:nth(2, StrArgList), " |"));
+	string:lexemes(lists:nth(2, StrArgList), " |"));
     register ->
       lists_key_replace(2, StrArgList,
-	string:tokens(lists:nth(2, StrArgList), " |"));
+	string:lexemes(lists:nth(2, StrArgList), " |"));
     unregister ->
       lists_key_replace(2, StrArgList,
-	string:tokens(lists:nth(2, StrArgList), " |"));
+	string:lexemes(lists:nth(2, StrArgList), " |"));
     ets_new ->
       StrArgList1 = lists_key_replace(2, StrArgList,
-	string:tokens(lists:nth(2, StrArgList), " |")),
+	string:lexemes(lists:nth(2, StrArgList), " |")),
       lists_key_replace(4, StrArgList1,
-        string:tokens(ets_list_argtypes(lists:nth(4, StrArgList1)), " |"));
+        string:lexemes(ets_list_argtypes(lists:nth(4, StrArgList1)), " |"));
     ets_lookup ->
       StrArgList1 = lists_key_replace(2, StrArgList,
-        string:tokens(lists:nth(2, StrArgList), " |")),
+        string:lexemes(lists:nth(2, StrArgList), " |")),
       lists_key_replace(4, StrArgList1,
-        string:tokens(lists:nth(4, StrArgList1), " |"));
+        string:lexemes(lists:nth(4, StrArgList1), " |"));
     ets_insert ->
       StrArgList1 = lists_key_replace(2, StrArgList,
-        string:tokens(lists:nth(2, StrArgList), " |")),
+        string:lexemes(lists:nth(2, StrArgList), " |")),
       lists_key_replace(4, StrArgList1,
         ets_tuple_argtypes2(
         ets_tuple_argtypes1(lists:nth(4, StrArgList1), [], [], 0),
         []));
     mnesia_dirty_read1 ->
       lists_key_replace(2, StrArgList,
-        [mnesia_tuple_argtypes(T) || T <- string:tokens(
+        [mnesia_tuple_argtypes(T) || T <- string:lexemes(
         lists:nth(2, StrArgList), " |")]);
     mnesia_dirty_read2 ->
       lists_key_replace(2, StrArgList,
-        string:tokens(lists:nth(2, StrArgList), " |"));
+        string:lexemes(lists:nth(2, StrArgList), " |"));
     mnesia_dirty_write1 ->
       lists_key_replace(2, StrArgList,
-        [mnesia_record_tab(R) || R <- string:tokens(
+        [mnesia_record_tab(R) || R <- string:lexemes(
         lists:nth(2, StrArgList), " |")]);
     mnesia_dirty_write2 ->
       lists_key_replace(2, StrArgList,
-        string:tokens(lists:nth(2, StrArgList), " |"));
+        string:lexemes(lists:nth(2, StrArgList), " |"));
     function_call -> StrArgList
   end.
 
@@ -1943,18 +1941,16 @@ format_type(Type, State) ->
   erl_types:t_to_string(Type, R).
 
 mnesia_record_tab(RecordStr) ->
-  case string:str(RecordStr, "#") =:= 1 of
-    true ->
-      "'" ++
-        string:sub_string(RecordStr, 2, string:str(RecordStr, "{") - 1) ++
-        "'";
-    false -> RecordStr
+  case erl_scan:string(RecordStr) of
+    {ok, [{'#', _}, {atom, _, Name}|_], _} ->
+      io_lib:write_string(atom_to_list(Name), $');
+    _ -> RecordStr
   end.
 
 mnesia_tuple_argtypes(TupleStr) ->
-  TupleStr1 = string:strip(TupleStr, left, ${),
-  [TupleStr2|_T] = string:tokens(TupleStr1, " ,"),
-  lists:flatten(string:tokens(TupleStr2, " |")).
+  TupleStr1 = string:trim(TupleStr, leading, "${"),
+  [TupleStr2|_T] = string:lexemes(TupleStr1, " ,"),
+  lists:flatten(string:lexemes(TupleStr2, " |")).
 
 -spec race_var_map(var_to_map1(), var_to_map2(), dict:dict(), op()) ->
         dict:dict().
@@ -2237,7 +2233,7 @@ var_type_analysis(FunDefArgs, FunCallTypes, WarnVarArgs, RaceWarnTag,
       case lists_key_member_lists(Vars, FunVarArgs) of
         0 -> [Vars, WVA2, WVA3, WVA4];
         N when is_integer(N) ->
-          NewWVA2 = string:tokens(lists:nth(N + 1, FunVarArgs), " |"),
+          NewWVA2 = string:lexemes(lists:nth(N + 1, FunVarArgs), " |"),
           [Vars, NewWVA2, WVA3, WVA4]
       end;
     ?WARN_WHEREIS_UNREGISTER ->
@@ -2246,7 +2242,7 @@ var_type_analysis(FunDefArgs, FunCallTypes, WarnVarArgs, RaceWarnTag,
       case lists_key_member_lists(Vars, FunVarArgs) of
         0 -> [Vars, WVA2];
         N when is_integer(N) ->
-          NewWVA2 = string:tokens(lists:nth(N + 1, FunVarArgs), " |"),
+          NewWVA2 = string:lexemes(lists:nth(N + 1, FunVarArgs), " |"),
           [Vars, NewWVA2]
       end;
     ?WARN_ETS_LOOKUP_INSERT ->
@@ -2256,7 +2252,7 @@ var_type_analysis(FunDefArgs, FunCallTypes, WarnVarArgs, RaceWarnTag,
         case lists_key_member_lists(Vars1, FunVarArgs) of
           0 -> [Vars1, WVA2];
           N1 when is_integer(N1) ->
-            NewWVA2 = string:tokens(lists:nth(N1 + 1, FunVarArgs), " |"),
+            NewWVA2 = string:lexemes(lists:nth(N1 + 1, FunVarArgs), " |"),
             [Vars1, NewWVA2]
         end,
       Vars2 =
@@ -2286,10 +2282,10 @@ var_type_analysis(FunDefArgs, FunCallTypes, WarnVarArgs, RaceWarnTag,
           NewWVA2 =
             case Arity of
               1 ->
-                [mnesia_record_tab(R) || R <- string:tokens(
+                [mnesia_record_tab(R) || R <- string:lexemes(
                   lists:nth(2, FunVarArgs), " |")];
               2 ->
-                string:tokens(lists:nth(N + 1, FunVarArgs), " |")
+                string:lexemes(lists:nth(N + 1, FunVarArgs), " |")
             end,
           [Vars, NewWVA2|T]
       end
diff --git a/lib/dialyzer/src/dialyzer_typesig.erl b/lib/dialyzer/src/dialyzer_typesig.erl
index d03326ec97..b1f6a54503 100644
--- a/lib/dialyzer/src/dialyzer_typesig.erl
+++ b/lib/dialyzer/src/dialyzer_typesig.erl
@@ -418,6 +418,7 @@ traverse(Tree, DefinedVars, State) ->
 	match_fail -> throw(error);
 	raise -> throw(error);
 	bs_init_writable -> {State, t_from_term(<<>>)};
+	build_stacktrace -> {State, t_list()};
 	Other -> erlang:error({'Unsupported primop', Other})
       end;
     'receive' ->
diff --git a/lib/dialyzer/src/dialyzer_utils.erl b/lib/dialyzer/src/dialyzer_utils.erl
index 9b8fbc67eb..abd89034f3 100644
--- a/lib/dialyzer/src/dialyzer_utils.erl
+++ b/lib/dialyzer/src/dialyzer_utils.erl
@@ -120,92 +120,10 @@ get_core_from_beam(File, Opts) ->
 	  {error, "  Could not get Core Erlang code for: " ++ File ++ "\n"}
       end;
     _ ->
-      deprecated_get_core_from_beam(File, Opts)
+      {error, "  Could not get Core Erlang code for: " ++ File ++ "\n" ++
+        "  Recompile with +debug_info or analyze starting from source code"}
   end.
 
-deprecated_get_core_from_beam(File, Opts) ->
-  case get_abstract_code_from_beam(File) of
-    error ->
-      {error, "  Could not get abstract code for: " ++ File ++ "\n" ++
-       "  Recompile with +debug_info or analyze starting from source code"};
-    {ok, AbstrCode} ->
-      case get_compile_options_from_beam(File) of
-        error ->
-          {error, "  Could not get compile options for: " ++ File ++ "\n" ++
-            "  Recompile or analyze starting from source code"};
-        {ok, CompOpts} ->
-          case get_core_from_abstract_code(AbstrCode, Opts ++ CompOpts) of
-            error ->
-              {error, "  Could not get core Erlang code for: " ++ File};
-            {ok, _} = Core ->
-              Core
-          end
-      end
-  end.
-
-get_abstract_code_from_beam(File) ->
-  case beam_lib:chunks(File, [abstract_code]) of
-    {ok, {_, List}} ->
-      case lists:keyfind(abstract_code, 1, List) of
-        {abstract_code, {raw_abstract_v1, Abstr}} -> {ok, Abstr};
-        _ -> error
-      end;
-    _ ->
-      %% No or unsuitable abstract code.
-      error
-  end.
-
-get_compile_options_from_beam(File) ->
-  case beam_lib:chunks(File, [compile_info]) of
-    {ok, {_, List}} ->
-      case lists:keyfind(compile_info, 1, List) of
-        {compile_info, CompInfo} -> compile_info_to_options(CompInfo);
-        _ -> error
-      end;
-    _ ->
-      %% No or unsuitable compile info.
-      error
-  end.
-
-compile_info_to_options(CompInfo) ->
-  case lists:keyfind(options, 1, CompInfo) of
-    {options, CompOpts} -> {ok, CompOpts};
-    _ -> error
-  end.
-
-get_core_from_abstract_code(AbstrCode, Opts) ->
-  %% We do not want the parse_transforms around since we already
-  %% performed them. In some cases we end up in trouble when
-  %% performing them again.
-  AbstrCode1 = cleanup_parse_transforms(AbstrCode),
-  %% Remove parse_transforms (and other options) from compile options.
-  Opts2 = cleanup_compile_options(Opts),
-  try compile:noenv_forms(AbstrCode1, Opts2 ++ src_compiler_opts()) of
-    {ok, _, Core} -> {ok, Core};
-    _What -> error
-  catch
-    error:_ -> error
-  end.
-
-cleanup_parse_transforms([{attribute, _, compile, {parse_transform, _}}|Left]) ->
-  cleanup_parse_transforms(Left);
-cleanup_parse_transforms([Other|Left]) ->
-  [Other|cleanup_parse_transforms(Left)];
-cleanup_parse_transforms([]) ->
-  [].
-
-cleanup_compile_options(Opts) ->
-  lists:filter(fun keep_compile_option/1, Opts).
-
-%% Using abstract, not asm or core.
-keep_compile_option(from_asm) -> false;
-keep_compile_option(from_core) -> false;
-%% The parse transform will already have been applied, may cause
-%% problems if it is re-applied.
-keep_compile_option({parse_transform, _}) -> false;
-keep_compile_option(warnings_as_errors) -> false;
-keep_compile_option(_) -> true.
-
 %% ============================================================================
 %%
 %%  Typed Records
diff --git a/lib/dialyzer/test/behaviour_SUITE_data/results/gen_server_incorrect_args b/lib/dialyzer/test/behaviour_SUITE_data/results/gen_server_incorrect_args
index 1eb8cd455b..1be0ce0d8c 100644
--- a/lib/dialyzer/test/behaviour_SUITE_data/results/gen_server_incorrect_args
+++ b/lib/dialyzer/test/behaviour_SUITE_data/results/gen_server_incorrect_args
@@ -1,5 +1,5 @@
 
 gen_server_incorrect_args.erl:3: Undefined callback function handle_cast/2 (behaviour gen_server)
 gen_server_incorrect_args.erl:3: Undefined callback function init/1 (behaviour gen_server)
-gen_server_incorrect_args.erl:7: The inferred return type of handle_call/3 ({'no'} | {'ok'}) has nothing in common with {'noreply',_} | {'noreply',_,'hibernate' | 'infinity' | non_neg_integer()} | {'reply',_,_} | {'stop',_,_} | {'reply',_,_,'hibernate' | 'infinity' | non_neg_integer()} | {'stop',_,_,_}, which is the expected return type for the callback of the gen_server behaviour
+gen_server_incorrect_args.erl:7: The inferred return type of handle_call/3 ({'no'} | {'ok'}) has nothing in common with {'noreply',_} | {'noreply',_,'hibernate' | 'infinity' | non_neg_integer() | {'continue',_}} | {'reply',_,_} | {'stop',_,_} | {'reply',_,_,'hibernate' | 'infinity' | non_neg_integer() | {'continue',_}} | {'stop',_,_,_}, which is the expected return type for the callback of the gen_server behaviour
 gen_server_incorrect_args.erl:7: The inferred type for the 2nd argument of handle_call/3 ('boo' | 'foo') is not a supertype of {pid(),_}, which is expected type for this argument in the callback of the gen_server behaviour
diff --git a/lib/dialyzer/test/dialyzer_common.erl b/lib/dialyzer/test/dialyzer_common.erl
index 48083a2731..1a8403f486 100644
--- a/lib/dialyzer/test/dialyzer_common.erl
+++ b/lib/dialyzer/test/dialyzer_common.erl
@@ -221,13 +221,9 @@ get_suites(Dir) ->
     end.
 
 suffix(String, Suffix) ->
-    case string:rstr(String, Suffix) of
-	0 -> no;
-	Index ->
-	    case string:substr(String, Index) =:= Suffix of
-		true -> {yes, string:sub_string(String,1,Index-1)};
-		false -> no
-	    end
+    case string:split(String, Suffix, trailing) of
+	[Prefix,[]] -> {yes, Prefix};
+        _ -> no
     end.
 
 -spec create_suite(string()) -> 'ok'.
diff --git a/lib/dialyzer/test/small_SUITE_data/results/maps_sum b/lib/dialyzer/test/small_SUITE_data/results/maps_sum
index bd192bdb93..b29ac77d88 100644
--- a/lib/dialyzer/test/small_SUITE_data/results/maps_sum
+++ b/lib/dialyzer/test/small_SUITE_data/results/maps_sum
@@ -1,4 +1,4 @@
 
-maps_sum.erl:15: Invalid type specification for function maps_sum:wrong1/1. The success typing is (map()) -> any()
+maps_sum.erl:15: Invalid type specification for function maps_sum:wrong1/1. The success typing is (maps:iterator() | map()) -> any()
 maps_sum.erl:26: Function wrong2/1 has no local return
 maps_sum.erl:27: The call lists:foldl(fun((_,_,_) -> any()),0,Data::any()) will never return since it differs in the 1st argument from the success typing arguments: (fun((_,_) -> any()),any(),[any()])
diff --git a/lib/edoc/src/edoc_layout.erl b/lib/edoc/src/edoc_layout.erl
index eafab0588e..baa147410b 100644
--- a/lib/edoc/src/edoc_layout.erl
+++ b/lib/edoc/src/edoc_layout.erl
@@ -608,7 +608,7 @@ etypef([Cs | L], St, O, R, Opts) ->
 app_fix(L, Opts) ->
     try
         {"//" ++ R1,L2} = app_fix1(L, 1),
-        [App, Mod] = string:tokens(R1, "/"),
+        [App, Mod] = string:lexemes(R1, "/"),
         "//" ++ atom(App, Opts) ++ "/" ++ atom(Mod, Opts) ++ L2
     catch _:_ -> L
     end.
@@ -1120,13 +1120,13 @@ ot_integer(E) ->
     {integer,0,list_to_integer(get_attrval(value, E))}.
 
 ot_range(E) ->
-    [I1, I2] = string:tokens(get_attrval(value, E), "."),
+    [I1, I2] = string:lexemes(get_attrval(value, E), "."),
     {type,0,range,[{integer,0,list_to_integer(I1)},
                    {integer,0,list_to_integer(I2)}]}.
 
 ot_binary(E) ->
     {Base, Unit} =
-        case string:tokens(get_attrval(value, E), ",:*><") of
+        case string:lexemes(get_attrval(value, E), ",:*><") of
             [] ->
                 {0, 0};
             ["_",B] ->
diff --git a/lib/edoc/src/edoc_specs.erl b/lib/edoc/src/edoc_specs.erl
index 4e45e42f20..7b451c43f8 100644
--- a/lib/edoc/src/edoc_specs.erl
+++ b/lib/edoc/src/edoc_specs.erl
@@ -83,7 +83,7 @@ spec(Form, Clause) ->
 %% the given Erlang spec and an empty list of arguments.
 dummy_spec(Form) ->
     {#t_name{name = Name}, Arity, TypeSpecs} = get_spec(Form),
-    As = string:join(lists:duplicate(Arity, "_X"), ","),
+    As = lists:join(",", lists:duplicate(Arity, "_X")),
     S = lists:flatten(io_lib:format("~p(~s) -> true\n", [Name, As])),
     #tag{name = spec, line = get_line(element(2, hd(TypeSpecs))),
          origin = code, data = S}.
diff --git a/lib/eldap/src/eldap.erl b/lib/eldap/src/eldap.erl
index 625309271b..2b84872b92 100644
--- a/lib/eldap/src/eldap.erl
+++ b/lib/eldap/src/eldap.erl
@@ -1368,9 +1368,9 @@ rm_leading_slash(Tail)      -> Tail.
 parse_attributes([$?|Tail]) ->
     case split_string(Tail,$?) of
         {[],Attributes} ->
-	    {[],{attributes,string:tokens(Attributes,",")}};
+	    {[],{attributes,string:lexemes(Attributes,",")}};
         {Attributes,Rest} ->
-            {Rest,{attributes,string:tokens(Attributes,",")}}
+            {Rest,{attributes,string:lexemes(Attributes,",")}}
     end.
 
 parse_hostport(Str) ->
diff --git a/lib/erl_docgen/priv/dtd/erlref.dtd b/lib/erl_docgen/priv/dtd/erlref.dtd
index 615b88b61a..78d6771f52 100644
--- a/lib/erl_docgen/priv/dtd/erlref.dtd
+++ b/lib/erl_docgen/priv/dtd/erlref.dtd
@@ -33,4 +33,5 @@
 <!ATTLIST name                 name CDATA #IMPLIED
                                arity CDATA #IMPLIED
 	                       clause_i CDATA #IMPLIED
+                               anchor CDATA #IMPLIED
                                n_vars CDATA #IMPLIED>
diff --git a/lib/erl_docgen/priv/xsl/db_html.xsl b/lib/erl_docgen/priv/xsl/db_html.xsl
index 75614392fb..5b7eae4f73 100644
--- a/lib/erl_docgen/priv/xsl/db_html.xsl
+++ b/lib/erl_docgen/priv/xsl/db_html.xsl
@@ -172,6 +172,7 @@
   <xsl:template name="spec_name">
     <xsl:variable name="name" select="@name"/>
     <xsl:variable name="arity" select="@arity"/>
+    <xsl:variable name="anchor" select="@anchor"/>
     <xsl:variable name="spec0">
       <xsl:call-template name="find_spec"/>
     </xsl:variable>
@@ -198,6 +199,11 @@
 	  </xsl:otherwise>
         </xsl:choose>
 
+	<!-- Insert an anchor for "anchor" attribute -->
+	<xsl:if test="string-length($anchor) > 0">
+	      <a name="{$anchor}"></a>
+	</xsl:if>
+
         <xsl:variable name="global_types" select="ancestor::erlref/datatypes"/>
 	<xsl:variable name="local_types"
 		      select="../type[string-length(@name) > 0]"/>
diff --git a/lib/erl_docgen/src/docgen_edoc_xml_cb.erl b/lib/erl_docgen/src/docgen_edoc_xml_cb.erl
index 91422c8910..b065c18cda 100644
--- a/lib/erl_docgen/src/docgen_edoc_xml_cb.erl
+++ b/lib/erl_docgen/src/docgen_edoc_xml_cb.erl
@@ -11,7 +11,7 @@
 %% limitations under the License.
 %%
 %% Copyright (c) 2001-2016 Richard Carlsson. Parts written by Ericsson
-%% are Copyright (c) Ericsson AB 2001-2012. All Rights Reserved.
+%% are Copyright (c) Ericsson AB 2001-2017. All Rights Reserved.
 %%
 
 -module(docgen_edoc_xml_cb).
@@ -113,7 +113,7 @@ root_attributes(Element, Opts) ->
 %% epp:default_encoding/0 returns 'utf8'
 reformat_encoding(utf8) -> "UTF-8";
 reformat_encoding(List) when is_list(List) ->
-    case string:to_lower(List) of
+    case string:lowercase(List) of
         "utf8" -> "UTF-8";
         _ -> List
     end;
diff --git a/lib/erl_docgen/src/docgen_otp_specs.erl b/lib/erl_docgen/src/docgen_otp_specs.erl
index 126229ecc9..9f2b401f93 100644
--- a/lib/erl_docgen/src/docgen_otp_specs.erl
+++ b/lib/erl_docgen/src/docgen_otp_specs.erl
@@ -297,7 +297,7 @@ indent(L) ->
 app_fix(L) ->
     try
         {"//" ++ R1,L2} = app_fix(L, 1),
-        [App, Mod] = string:tokens(R1, "/"),
+        [App, Mod] = string:lexemes(R1, "/"),
         "//" ++ atom(App) ++ "/" ++ atom(Mod) ++ L2
     catch _:_ -> L
     end.
@@ -585,13 +585,13 @@ ot_integer(E) ->
     {integer,0,list_to_integer(get_attrval(value, E))}.
 
 ot_range(E) ->
-    [I1, I2] = string:tokens(get_attrval(value, E), "."),
+    [I1, I2] = string:lexemes(get_attrval(value, E), "."),
     {type,0,range,[{integer,0,list_to_integer(I1)},
                    {integer,0,list_to_integer(I2)}]}.
 
 ot_binary(E) ->
     {Base, Unit} =
-        case string:tokens(get_attrval(value, E), ",:*><") of
+        case string:lexemes(get_attrval(value, E), ",:*><") of
             [] ->
                 {0, 0};
             ["_",B] ->
diff --git a/lib/erl_interface/test/ei_accept_SUITE.erl b/lib/erl_interface/test/ei_accept_SUITE.erl
index e06ee762d7..6676e73e21 100644
--- a/lib/erl_interface/test/ei_accept_SUITE.erl
+++ b/lib/erl_interface/test/ei_accept_SUITE.erl
@@ -25,7 +25,8 @@
 -include("ei_accept_SUITE_data/ei_accept_test_cases.hrl").
 
 -export([all/0, suite/0,
-         ei_accept/1, ei_threaded_accept/1]).
+         ei_accept/1, ei_threaded_accept/1,
+         monitor_ei_process/1]).
 
 -import(runner, [get_term/1,send_term/2]).
 
@@ -34,7 +35,8 @@ suite() ->
      {timetrap, {seconds, 30}}].
 
 all() -> 
-    [ei_accept, ei_threaded_accept].
+    [ei_accept, ei_threaded_accept,
+     monitor_ei_process].
 
 ei_accept(Config) when is_list(Config) ->
     P = runner:start(?interpret),
@@ -44,33 +46,32 @@ ei_accept(Config) when is_list(Config) ->
     io:format("Myname ~p ~n",  [Myname]),
     EINode = list_to_atom("c42@"++Myname),
     io:format("EINode ~p ~n",  [EINode]),
+
+    %% We take this opportunity to also test export-funs and bit-strings
+    %% with (ugly) tuple fallbacks.
+    %% Test both toward pending connection and established connection.
+    RealTerms = [<<1:1>>,     fun lists:map/2],
+    Fallbacks = [{<<128>>,1}, {lists,map}],
+
     Self = self(),
-    TermToSend= {call, Self, "Test"},
-    F= fun() ->
-               case waitfornode("c42",20) of
-                   true ->
-                       {any, EINode} ! TermToSend,
-                       Self ! sent_ok;
-                   false ->
-                       Self ! never_published
-               end,
-               ok
-       end,
-
-    spawn(F),
+    Funny = fun() -> hello end,
+    TermToSend = {call, Self, "Test", Funny, RealTerms},
+    TermToGet  = {call, Self, "Test", Funny, Fallbacks},
     Port = 6543,
-    {ok, Fd, _Node} = ei_accept(P, Port),
-    TermReceived= ei_receive(P, Fd),
-    io:format("Sent ~p received ~p ~n", [TermToSend, TermReceived]),
-    TermToSend= TermReceived,
-    receive
-        sent_ok ->
-            ok;
-        Unknown ->
-            io:format("~p ~n", [Unknown])
-    after 1000 ->
-              io:format("timeout ~n")
-    end,
+    {ok, ListenFd} = ei_publish(P, Port),
+    {any, EINode} ! TermToSend,
+
+    {ok, Fd, _Node} = ei_accept(P, ListenFd),
+    Got1 = ei_receive(P, Fd),
+
+    %% Send again, now without auto-connect
+    {any, EINode} ! TermToSend,
+    Got2 = ei_receive(P, Fd),
+
+    io:format("Sent ~p~nExp. ~p~nGot1 ~p~nGot2 ~p~n", [TermToSend, TermToGet, Got1, Got2]),
+    TermToGet = Got1,
+    TermToGet = Got2,
+
     runner:finish(P),
     ok.
 
@@ -87,6 +88,41 @@ ei_threaded_accept(Config) when is_list(Config) ->
     [receive I -> ok end || I <- lists:seq(0, N-1) ],
     ok.
 
+
+%% Test erlang:monitor toward erl_interface "processes"
+monitor_ei_process(Config) when is_list(Config) ->
+    P = runner:start(?interpret),
+    0 = ei_connect_init(P, 42, erlang:get_cookie(), 0),
+
+    Myname = hd(tl(string:tokens(atom_to_list(node()), "@"))),
+    io:format("Myname ~p ~n",  [Myname]),
+    EINode = list_to_atom("c42@"++Myname),
+    io:format("EINode ~p ~n",  [EINode]),
+
+    Self = self(),
+    Port = 6543,
+    {ok, ListenFd} = ei_publish(P, Port),
+    MRef1 = erlang:monitor(process, {any, EINode}),
+    {any, EINode} ! hello,
+
+    {ok, Fd, _Node} = ei_accept(P, ListenFd),
+    hello = ei_receive(P, Fd),
+
+    %% Again, now on an established connection.
+    MRef2 = erlang:monitor(process, {any, EINode}),
+    {any, EINode} ! hello,
+    hello = ei_receive(P, Fd),
+
+    ok = receive M -> M after 0 -> ok end,
+
+    runner:finish(P),
+
+    [{'DOWN', MRef1, process, {any, EINode}, noconnection},
+     {'DOWN', MRef2, process, {any, EINode}, noconnection}
+    ] = lists:sort(flush(2, 1000)),
+
+    ok.
+
 waitfornode(String,0) ->
     io:format("~s never published itself.~n",[String]),
     false;
@@ -137,8 +173,15 @@ ei_connect_init(P, Num, Cookie, Creation) ->
         {term,Int} when is_integer(Int) -> Int
     end.
 
-ei_accept(P, PortNo) ->
-    send_command(P, ei_accept, [PortNo]),
+ei_publish(P, PortNo) ->
+    send_command(P, ei_publish, [PortNo]),
+    case get_term(P) of
+        {term,{ListenFd, EpmdFd, _}} when ListenFd >= 0, EpmdFd >= 0 -> {ok, ListenFd};
+        {term,{_, _, Errno}} -> {error,Errno}
+    end.
+
+ei_accept(P, ListenFd) ->
+    send_command(P, ei_accept, [ListenFd]),
     case get_term(P) of
         {term,{Fd, _, Node}} when Fd >= 0 -> {ok, Fd, Node};
         {term,{_Fd, Errno, _Node}} -> {error,Errno}
@@ -151,3 +194,12 @@ ei_receive(P, Fd) ->
 
 send_command(P, Name, Args) ->
     runner:send_term(P, {Name,list_to_tuple(Args)}).
+
+flush(0, Timeout) ->
+    flush(1, Timeout div 10);
+flush(Expected, Timeout) ->
+    receive M ->
+            [M | flush(Expected-1, Timeout)]
+    after Timeout ->
+            []
+    end.
diff --git a/lib/erl_interface/test/ei_accept_SUITE_data/ei_accept_test.c b/lib/erl_interface/test/ei_accept_SUITE_data/ei_accept_test.c
index 7b81ee5491..2b62d7c3a4 100644
--- a/lib/erl_interface/test/ei_accept_SUITE_data/ei_accept_test.c
+++ b/lib/erl_interface/test/ei_accept_SUITE_data/ei_accept_test.c
@@ -43,6 +43,7 @@
 #include "ei_runner.h"
 
 static void cmd_ei_connect_init(char* buf, int len);
+static void cmd_ei_publish(char* buf, int len);
 static void cmd_ei_accept(char* buf, int len);
 static void cmd_ei_receive(char* buf, int len);
 static void cmd_ei_unpublish(char* buf, int len);
@@ -58,6 +59,7 @@ static struct {
     void (*func)(char* buf, int len);
 } commands[] = {
     "ei_connect_init",  3, cmd_ei_connect_init,
+    "ei_publish", 	1, cmd_ei_publish,
     "ei_accept", 	1, cmd_ei_accept,
     "ei_receive",  	1, cmd_ei_receive,
     "ei_unpublish",     0, cmd_ei_unpublish
@@ -149,11 +151,10 @@ static int my_listen(int port)
     return listen_fd;
 }
 
-static void cmd_ei_accept(char* buf, int len)
+static void cmd_ei_publish(char* buf, int len)
 {
     int index = 0;
     int listen, r;
-    ErlConnect conn;
     long port;
     ei_x_buff x;
     int i;
@@ -170,6 +171,29 @@ static void cmd_ei_accept(char* buf, int len)
 #ifdef VXWORKS
     save_fd(i);
 #endif
+    /* send listen-fd, result and errno */
+    ei_x_new_with_version(&x);
+    ei_x_encode_tuple_header(&x, 3);
+    ei_x_encode_long(&x, listen);
+    ei_x_encode_long(&x, i);
+    ei_x_encode_long(&x, erl_errno);
+    send_bin_term(&x);
+    ei_x_free(&x);
+}
+
+static void cmd_ei_accept(char* buf, int len)
+{
+    int index = 0;
+    int r;
+    ErlConnect conn;
+    long listen;
+    ei_x_buff x;
+    int i;
+
+    /* get port */
+    if (ei_decode_long(buf, &index, &listen) < 0)
+	fail("expected int (listen fd)");
+
     r = ei_accept(&ec, listen, &conn);
 #ifdef VXWORKS
     save_fd(r);
@@ -200,7 +224,7 @@ static void cmd_ei_receive(char* buf, int len)
 	if (got == ERL_TICK)
 	    continue;
 	if (got == ERL_ERROR)
-	    fail("ei_xreceive_msg");
+	    fail1("ei_xreceive_msg, got==%d", got);
 	break;
     }
     index = 1;
diff --git a/lib/erl_interface/test/runner.erl b/lib/erl_interface/test/runner.erl
index 1084eec2a3..cbdeb3c8a9 100644
--- a/lib/erl_interface/test/runner.erl
+++ b/lib/erl_interface/test/runner.erl
@@ -67,7 +67,12 @@ start({Prog, Tc}) when is_list(Prog), is_integer(Tc) ->
 
 finish(Port) when is_port(Port) ->
     send_eot(Port),
-    recv_eot(Port).
+    ok = recv_eot(Port),
+    0 = receive
+            {Port,{exit_status,Status}} ->
+                Status
+        end,
+    ok.
 
 %% Sends an Erlang term to a C program.
 
diff --git a/lib/et/src/et_collector.erl b/lib/et/src/et_collector.erl
index b0f016a8ea..ffe244324c 100644
--- a/lib/et/src/et_collector.erl
+++ b/lib/et/src/et_collector.erl
@@ -1135,7 +1135,7 @@ handle_info(Info, S) ->
     noreply(S).
 
 listen_on_trace_port(Node, Port, S) ->
-    [_Name, Host] = string:tokens(atom_to_list(Node), [$@]),
+    [_Name, Host] = string:lexemes(atom_to_list(Node), [$@]),
     case catch start_trace_client(self(), ip, {Host, Port}) of
         {trace_client_pid, RemotePid} ->
             rpc:call(Node, et_selector, change_pattern, [S#state.trace_pattern]),
diff --git a/lib/eunit/src/eunit_lib.erl b/lib/eunit/src/eunit_lib.erl
index e340f50a3c..d1bd160ea1 100644
--- a/lib/eunit/src/eunit_lib.erl
+++ b/lib/eunit/src/eunit_lib.erl
@@ -391,7 +391,7 @@ fun_parent(F) ->
 
 -ifdef(TEST).
 fun_parent_test() ->
-    {?MODULE,fun_parent_test,0} = fun_parent(fun () -> ok end).
+    {?MODULE,fun_parent_test,0} = fun_parent(fun (A) -> {ok,A} end).
 -endif.
 
 %% ---------------------------------------------------------------------
diff --git a/lib/hipe/cerl/erl_bif_types.erl b/lib/hipe/cerl/erl_bif_types.erl
index a3a936322a..462a1f9dcd 100644
--- a/lib/hipe/cerl/erl_bif_types.erl
+++ b/lib/hipe/cerl/erl_bif_types.erl
@@ -1701,24 +1701,6 @@ type(maps, size, 1, Xs, Opaques) ->
 		 t_from_range(LowerBound, UpperBound)
 	     end
 	 end, Opaques);
-type(maps, to_list, 1, Xs, Opaques) ->
-  strict(maps, to_list, 1, Xs,
-	 fun ([Map]) ->
-	     DefK = t_map_def_key(Map, Opaques),
-	     DefV = t_map_def_val(Map, Opaques),
-	     Pairs = t_map_entries(Map, Opaques),
-	     EType = lists:foldl(
-		       fun({K,_,V},EType0) ->
-			   case t_is_none(V) of
-			     true -> t_subtract(EType0, t_tuple([K,t_any()]));
-			     false -> t_sup(EType0, t_tuple([K,V]))
-			   end
-		       end, t_tuple([DefK, DefV]), Pairs),
-	     case t_is_none(EType) of
-	       true -> t_nil();
-	       false -> t_list(EType)
-	     end
-	 end, Opaques);
 type(maps, update, 3, Xs, Opaques) ->
   strict(maps, update, 3, Xs,
 	 fun ([Key, Value, Map]) ->
@@ -2648,8 +2630,6 @@ arg_types(maps, put, 3) ->
   [t_any(), t_any(), t_map()];
 arg_types(maps, size, 1) ->
   [t_map()];
-arg_types(maps, to_list, 1) ->
-  [t_map()];
 arg_types(maps, update, 3) ->
   [t_any(), t_any(), t_map()];
 arg_types(M, F, A) when is_atom(M), is_atom(F),
diff --git a/lib/hipe/cerl/erl_types.erl b/lib/hipe/cerl/erl_types.erl
index 4e0f93212d..77a2a7401c 100644
--- a/lib/hipe/cerl/erl_types.erl
+++ b/lib/hipe/cerl/erl_types.erl
@@ -4253,13 +4253,13 @@ t_to_string(?identifier(Set), _RecDict) ->
   case Set of
     ?any -> "identifier()";
     _ ->
-      string:join([flat_format("~w()", [T]) || T <- set_to_list(Set)], " | ")
+      flat_join([flat_format("~w()", [T]) || T <- set_to_list(Set)], " | ")
   end;
 t_to_string(?opaque(Set), RecDict) ->
-  string:join([opaque_type(Mod, Name, Args, S, RecDict) ||
-                #opaque{mod = Mod, name = Name, struct = S, args = Args}
-                  <- set_to_list(Set)],
-	      " | ");
+  flat_join([opaque_type(Mod, Name, Args, S, RecDict) ||
+              #opaque{mod = Mod, name = Name, struct = S, args = Args}
+                <- set_to_list(Set)],
+            " | ");
 t_to_string(?matchstate(Pres, Slots), RecDict) ->
   flat_format("ms(~ts,~ts)", [t_to_string(Pres, RecDict),
                               t_to_string(Slots,RecDict)]);
@@ -4350,9 +4350,9 @@ t_to_string(?map(Pairs0,DefK,DefV), RecDict) ->
 		  end end,
   StrMand = [{Tos(K),Tos(V)}||{K,?mand,V}<-Pairs],
   StrOpt  = [{Tos(K),Tos(V)}||{K,?opt,V}<-Pairs],
-  "#{" ++ string:join([K ++ ":=" ++ V||{K,V}<-StrMand]
-		      ++ [K ++ "=>" ++ V||{K,V}<-StrOpt]
-		      ++ ExtraEl, ", ") ++ "}";
+  "#{" ++ flat_join([K ++ ":=" ++ V||{K,V}<-StrMand]
+                    ++ [K ++ "=>" ++ V||{K,V}<-StrOpt]
+                    ++ ExtraEl, ", ") ++ "}";
 t_to_string(?tuple(?any, ?any, ?any), _RecDict) -> "tuple()";
 t_to_string(?tuple(Elements, _Arity, ?any), RecDict) ->   
   "{" ++ comma_sequence(Elements, RecDict) ++ "}";
@@ -4375,7 +4375,7 @@ t_to_string(?var(Id), _RecDict) when is_integer(Id) ->
 
 record_to_string(Tag, [_|Fields], FieldNames, RecDict) ->
   FieldStrings = record_fields_to_string(Fields, FieldNames, RecDict, []),
-  "#" ++ atom_to_string(Tag) ++ "{" ++ string:join(FieldStrings, ",") ++ "}".
+  "#" ++ atom_to_string(Tag) ++ "{" ++ flat_join(FieldStrings, ",") ++ "}".
 
 record_fields_to_string([F|Fs], [{FName, _Abstr, DefType}|FDefs],
                         RecDict, Acc) ->
@@ -4401,7 +4401,7 @@ record_field_diffs_to_string(?tuple([_|Fs], Arity, Tag), RecDict) ->
   {ok, FieldNames} = lookup_record(TagAtom, Arity-1, RecDict),
   %% io:format("RecCElems = ~p\nRecTypes = ~p\n", [Fs, FieldNames]),
   FieldDiffs = field_diffs(Fs, FieldNames, RecDict, []),
-  string:join(FieldDiffs, " and ").
+  flat_join(FieldDiffs, " and ").
 
 field_diffs([F|Fs], [{FName, _Abstr, DefType}|FDefs], RecDict, Acc) ->
   %% Don't care about opacity for now.
@@ -4421,11 +4421,11 @@ comma_sequence(Types, RecDict) ->
 	    true -> "_";
 	    false -> t_to_string(T, RecDict)
 	  end || T <- Types],
-  string:join(List, ",").
+  flat_join(List, ",").
 
 union_sequence(Types, RecDict) ->
   List = [t_to_string(T, RecDict) || T <- Types], 
-  string:join(List, " | ").
+  flat_join(List, " | ").
 
 -ifdef(DEBUG).
 opaque_type(Mod, Name, _Args, S, RecDict) ->
@@ -5265,7 +5265,7 @@ t_form_to_string({ann_type, _L, [Var, Type]}) ->
 t_form_to_string({paren_type, _L, [Type]}) ->
   flat_format("(~ts)", [t_form_to_string(Type)]);
 t_form_to_string({remote_type, _L, [{atom, _, Mod}, {atom, _, Name}, Args]}) ->
-  ArgString = "(" ++ string:join(t_form_to_string_list(Args), ",") ++ ")",
+  ArgString = "(" ++ flat_join(t_form_to_string_list(Args), ",") ++ ")",
   flat_format("~w:~tw", [Mod, Name]) ++ ArgString;
 t_form_to_string({type, _L, arity, []}) -> "arity()";
 t_form_to_string({type, _L, binary, []}) -> "binary()";
@@ -5288,7 +5288,7 @@ t_form_to_string({type, _L, 'fun', []}) -> "fun()";
 t_form_to_string({type, _L, 'fun', [{type, _, any}, Range]}) ->
   "fun(...) -> " ++ t_form_to_string(Range);
 t_form_to_string({type, _L, 'fun', [{type, _, product, Domain}, Range]}) ->
-  "fun((" ++ string:join(t_form_to_string_list(Domain), ",") ++ ") -> "
+  "fun((" ++ flat_join(t_form_to_string_list(Domain), ",") ++ ") -> "
     ++ t_form_to_string(Range) ++ ")";
 t_form_to_string({type, _L, iodata, []}) -> "iodata()";
 t_form_to_string({type, _L, iolist, []}) -> "iolist()";
@@ -5296,7 +5296,7 @@ t_form_to_string({type, _L, list, [Type]}) ->
   "[" ++ t_form_to_string(Type) ++ "]";
 t_form_to_string({type, _L, map, any}) -> "map()";
 t_form_to_string({type, _L, map, Args}) ->
-  "#{" ++ string:join(t_form_to_string_list(Args), ",") ++ "}";
+  "#{" ++ flat_join(t_form_to_string_list(Args), ",") ++ "}";
 t_form_to_string({type, _L, map_field_assoc, [Key, Val]}) ->
   t_form_to_string(Key) ++ "=>" ++ t_form_to_string(Val);
 t_form_to_string({type, _L, map_field_exact, [Key, Val]}) ->
@@ -5308,7 +5308,7 @@ t_form_to_string({type, _L, nonempty_list, [Type]}) ->
   "[" ++ t_form_to_string(Type) ++ ",...]";
 t_form_to_string({type, _L, nonempty_string, []}) -> "nonempty_string()";
 t_form_to_string({type, _L, product, Elements}) ->
-  "<" ++ string:join(t_form_to_string_list(Elements), ",") ++ ">";
+  "<" ++ flat_join(t_form_to_string_list(Elements), ",") ++ ">";
 t_form_to_string({type, _L, range, [From, To]} = Type) ->
   case {erl_eval:partial_eval(From), erl_eval:partial_eval(To)} of
     {{integer, _, FromVal}, {integer, _, ToVal}} ->
@@ -5318,7 +5318,7 @@ t_form_to_string({type, _L, range, [From, To]} = Type) ->
 t_form_to_string({type, _L, record, [{atom, _, Name}]}) ->
   flat_format("#~tw{}", [Name]);
 t_form_to_string({type, _L, record, [{atom, _, Name}|Fields]}) ->
-  FieldString = string:join(t_form_to_string_list(Fields), ","),
+  FieldString = flat_join(t_form_to_string_list(Fields), ","),
   flat_format("#~tw{~ts}", [Name, FieldString]);
 t_form_to_string({type, _L, field_type, [{atom, _, Name}, Type]}) ->
   flat_format("~tw::~ts", [Name, t_form_to_string(Type)]);
@@ -5326,9 +5326,9 @@ t_form_to_string({type, _L, term, []}) -> "term()";
 t_form_to_string({type, _L, timeout, []}) -> "timeout()";
 t_form_to_string({type, _L, tuple, any}) -> "tuple()";
 t_form_to_string({type, _L, tuple, Args}) ->
-  "{" ++ string:join(t_form_to_string_list(Args), ",") ++ "}";
+  "{" ++ flat_join(t_form_to_string_list(Args), ",") ++ "}";
 t_form_to_string({type, _L, union, Args}) ->
-  string:join(t_form_to_string_list(Args), " | ");
+  flat_join(t_form_to_string_list(Args), " | ");
 t_form_to_string({type, _L, Name, []} = T) ->
    try
      M = mod,
@@ -5346,7 +5346,7 @@ t_form_to_string({type, _L, Name, []} = T) ->
   end;
 t_form_to_string({user_type, _L, Name, List}) ->
   flat_format("~tw(~ts)",
-              [Name, string:join(t_form_to_string_list(List), ",")]);
+              [Name, flat_join(t_form_to_string_list(List), ",")]);
 t_form_to_string({type, L, Name, List}) ->
   %% Compatibility: modules compiled before Erlang/OTP 18.0.
   t_form_to_string({user_type, L, Name, List}).
@@ -5607,7 +5607,7 @@ set_to_string(Set) ->
 	 true -> io_lib:write_string(atom_to_list(X), $'); % stupid emacs '
 	 false -> flat_format("~tw", [X])
        end || X <- set_to_list(Set)],
-  string:join(L, " | ").
+  flat_join(L, " | ").
 
 set_min([H|_]) -> H.
 
@@ -5617,6 +5617,9 @@ set_max(Set) ->
 flat_format(F, S) ->
   lists:flatten(io_lib:format(F, S)).
 
+flat_join(List, Sep) ->
+  lists:flatten(lists:join(Sep, List)).
+
 %%=============================================================================
 %% 
 %% Utilities for the binary type
diff --git a/lib/hipe/doc/src/hipe_app.xml b/lib/hipe/doc/src/hipe_app.xml
index 9299c6d73f..aaeb06193d 100644
--- a/lib/hipe/doc/src/hipe_app.xml
+++ b/lib/hipe/doc/src/hipe_app.xml
@@ -99,17 +99,6 @@
       each mode.</p>
       </item>
 
-      <tag>Optimization for <c>receive</c> with unique references</tag>
-      <item><p>The BEAM compiler can do an optimization when
-      a <c>receive</c> statement is <em>only</em> waiting for messages
-      containing a reference created before the receive. All messages
-      that existed in the queue when the reference was created will be
-      bypassed, as they cannot possibly contain the reference. HiPE
-      does not implement this optimization.</p>
-      <p>An example of this is when
-      <c>gen_server:call()</c> waits for the reply message.</p>
-      </item>
-
     </taglist>
   </section>
   <section>
diff --git a/lib/hipe/icode/hipe_beam_to_icode.erl b/lib/hipe/icode/hipe_beam_to_icode.erl
index 2abecf7f18..7ff9fd83eb 100644
--- a/lib/hipe/icode/hipe_beam_to_icode.erl
+++ b/lib/hipe/icode/hipe_beam_to_icode.erl
@@ -415,11 +415,13 @@ trans_fun([{wait_timeout,{_,Lbl},Reg}|Instructions], Env) ->
   SuspTmout = hipe_icode:mk_if(suspend_msg_timeout,[],
 			       map_label(Lbl),hipe_icode:label_name(DoneLbl)),
   Movs ++ [SetTmout, SuspTmout, DoneLbl | trans_fun(Instructions,Env1)];
-%%--- recv_mark/1 & recv_set/1 ---  XXX: Handle better??
+%%--- recv_mark/1 & recv_set/1 ---
 trans_fun([{recv_mark,{f,_}}|Instructions], Env) ->
-  trans_fun(Instructions,Env);
+  Mark = hipe_icode:mk_primop([],recv_mark,[]),
+  [Mark | trans_fun(Instructions,Env)];
 trans_fun([{recv_set,{f,_}}|Instructions], Env) ->
-  trans_fun(Instructions,Env);
+  Set = hipe_icode:mk_primop([],recv_set,[]),
+  [Set | trans_fun(Instructions,Env)];
 %%--------------------------------------------------------------------
 %%--- Translation of arithmetics {bif,ArithOp, ...} ---
 %%--------------------------------------------------------------------
@@ -794,7 +796,7 @@ trans_fun([{bs_append,{f,Lbl},Size,W,R,U,Binary,{field_flags,F},Dst}|
   SizeArg = trans_arg(Size),
   BinArg = trans_arg(Binary),
   IcodeDst = mk_var(Dst),
-  Offset = mk_var(reg),
+  Offset = mk_var(reg_gcsafe),
   Base = mk_var(reg),
   trans_bin_call({hipe_bs_primop,{bs_append,W,R,U,F}},Lbl,[SizeArg,BinArg],
 		[IcodeDst,Base,Offset],
@@ -805,7 +807,7 @@ trans_fun([{bs_private_append,{f,Lbl},Size,U,Binary,{field_flags,F},Dst}|
   SizeArg = trans_arg(Size),
   BinArg = trans_arg(Binary),
   IcodeDst = mk_var(Dst),
-  Offset = mk_var(reg),
+  Offset = mk_var(reg_gcsafe),
   Base = mk_var(reg),
   trans_bin_call({hipe_bs_primop,{bs_private_append,U,F}},
 		 Lbl,[SizeArg,BinArg],
@@ -844,7 +846,7 @@ trans_fun([{bs_init2,{f,Lbl},Size,_Words,_LiveRegs,{field_flags,Flags0},X}|
 	   Instructions], Env) ->
   Dst = mk_var(X),
   Flags = resolve_native_endianess(Flags0),
-  Offset = mk_var(reg),
+  Offset = mk_var(reg_gcsafe),
   Base = mk_var(reg),
   {Name, Args} =
     case Size of
@@ -860,7 +862,7 @@ trans_fun([{bs_init_bits,{f,Lbl},Size,_Words,_LiveRegs,{field_flags,Flags0},X}|
 	   Instructions], Env) ->
   Dst = mk_var(X),
   Flags = resolve_native_endianess(Flags0),
-  Offset = mk_var(reg),
+  Offset = mk_var(reg_gcsafe),
   Base = mk_var(reg),
   {Name, Args} =
     case Size of
@@ -1157,6 +1159,11 @@ trans_fun([{put_map_exact,{f,Lbl},Map,Dst,_N,{list,Pairs}}|Instructions], Env) -
 	  gen_put_map_instrs(new, exact, TempMapVar, Dst, new, Pairs, Env1)
       end,
   [MapMove, TempMapMove, PutInstructions | trans_fun(Instructions, Env2)];
+%%--- build_stacktrace ---
+trans_fun([build_stacktrace|Instructions], Env) ->
+  Vars = [mk_var({x,0})], %{x,0} is implict arg and dst
+  [hipe_icode:mk_primop(Vars,build_stacktrace,Vars),
+   trans_fun(Instructions, Env)];
 %%--------------------------------------------------------------------
 %%--- ERROR HANDLING ---
 %%--------------------------------------------------------------------
@@ -1505,7 +1512,10 @@ clone_dst(Dest) ->
   New = 
     case hipe_icode:is_reg(Dest) of
       true ->
-	mk_var(reg);
+	case hipe_icode:reg_is_gcsafe(Dest) of
+	  true -> mk_var(reg_gcsafe);
+	  false -> mk_var(reg)
+	end;
       false ->
 	true = hipe_icode:is_var(Dest),	      
 	mk_var(new)
@@ -2126,7 +2136,12 @@ mk_var(reg) ->
   T = hipe_gensym:new_var(icode),
   V = (5*T)+4,
   hipe_gensym:update_vrange(icode,V),
-  hipe_icode:mk_reg(V).
+  hipe_icode:mk_reg(V);
+mk_var(reg_gcsafe) ->
+  T = hipe_gensym:new_var(icode),
+  V = (5*T)+4, % same namespace as 'reg'
+  hipe_gensym:update_vrange(icode,V),
+  hipe_icode:mk_reg_gcsafe(V).
 
 %%-----------------------------------------------------------------------
 %% Make an icode label of proper type
@@ -2296,6 +2311,12 @@ split_code([First|Code], Label, Instr) ->
 
 split_code([Instr|Code], Label, Instr, Prev, As) when Prev =:= Label ->
   split_code_final(Code, As);  % drop both label and instruction
+split_code([{icode_end_try}|_]=Code, Label, {try_case,_}, Prev, As)
+  when Prev =:= Label ->
+  %% The try_case has been replaced with try_end as an optimization.
+  %% Keep this instruction, since it might be the only try_end instruction
+  %% for this try/catch block.
+  split_code_final(Code, As);  % drop label
 split_code([Other|_Code], Label, Instr, Prev, _As) when Prev =:= Label ->
   ?EXIT({missing_instr_after_label, Label, Instr, [Other, Prev | _As]});
 split_code([Other|Code], Label, Instr, Prev, As) ->
diff --git a/lib/hipe/icode/hipe_icode.erl b/lib/hipe/icode/hipe_icode.erl
index 24b7ac4783..bc3403b0c5 100644
--- a/lib/hipe/icode/hipe_icode.erl
+++ b/lib/hipe/icode/hipe_icode.erl
@@ -515,10 +515,12 @@
 	 annotate_variable/2,  %% annotate_var_or_reg(VarOrReg, Type)
 	 unannotate_variable/1,%% unannotate_var_or_reg(VarOrReg)
 	 mk_reg/1,               %% mk_reg(Id)
+	 mk_reg_gcsafe/1,        %% mk_reg_gcsafe(Id)
 	 mk_fvar/1,              %% mk_fvar(Id)
 	 mk_new_var/0,           %% mk_new_var()
 	 mk_new_fvar/0,          %% mk_new_fvar()
 	 mk_new_reg/0,           %% mk_new_reg()
+	 mk_new_reg_gcsafe/0,    %% mk_new_reg_gcsafe()
 	 mk_phi/1,               %% mk_phi(Id)
 	 mk_phi/2                %% mk_phi(Id, ArgList)
 	]).
@@ -1260,14 +1262,22 @@ is_var(_) -> false.
 -spec mk_reg(non_neg_integer()) -> #icode_variable{kind::'reg'}.
 mk_reg(V) -> #icode_variable{name=V, kind=reg}.
 
--spec reg_name(#icode_variable{kind::'reg'}) -> non_neg_integer().
-reg_name(#icode_variable{name=Name, kind=reg}) -> Name.
+-spec mk_reg_gcsafe(non_neg_integer()) -> #icode_variable{kind::'reg_gcsafe'}.
+mk_reg_gcsafe(V) -> #icode_variable{name=V, kind=reg_gcsafe}.
 
--spec reg_is_gcsafe(#icode_variable{kind::'reg'}) -> 'false'.
-reg_is_gcsafe(#icode_variable{kind=reg}) -> false. % for now
+-spec reg_name(#icode_variable{kind::'reg'|'reg_gcsafe'})
+	      -> non_neg_integer().
+reg_name(#icode_variable{name=Name, kind=reg})        -> Name;
+reg_name(#icode_variable{name=Name, kind=reg_gcsafe}) -> Name.
+
+-spec reg_is_gcsafe(#icode_variable{kind::'reg'}) -> 'false';
+		   (#icode_variable{kind::'reg_gcsafe'}) -> 'true'.
+reg_is_gcsafe(#icode_variable{kind=reg})        -> false;
+reg_is_gcsafe(#icode_variable{kind=reg_gcsafe}) -> true.
 
 -spec is_reg(icode_argument()) -> boolean().
-is_reg(#icode_variable{kind=reg}) -> true;
+is_reg(#icode_variable{kind=reg})        -> true;
+is_reg(#icode_variable{kind=reg_gcsafe}) -> true;
 is_reg(_) -> false.
 
 -spec mk_fvar(non_neg_integer()) -> #icode_variable{kind::'fvar'}.
@@ -1676,6 +1686,16 @@ mk_new_reg() ->
   mk_reg(hipe_gensym:get_next_var(icode)).
 
 %%
+%% @doc Makes a new gcsafe register; that is, a register that is allowed to be
+%% live over calls and other operations that might cause GCs and thus move heap
+%% data around.
+%%
+
+-spec mk_new_reg_gcsafe() -> icode_reg().
+mk_new_reg_gcsafe() ->
+  mk_reg_gcsafe(hipe_gensym:get_next_var(icode)).
+
+%%
 %% @doc Makes a new label.
 %%
 
diff --git a/lib/hipe/icode/hipe_icode.hrl b/lib/hipe/icode/hipe_icode.hrl
index 380ddd8371..7ed80a9ed4 100644
--- a/lib/hipe/icode/hipe_icode.hrl
+++ b/lib/hipe/icode/hipe_icode.hrl
@@ -41,9 +41,9 @@
 
 -type variable_annotation() :: {atom(), any(), fun((any()) -> string())}.
 
--record(icode_variable, {name :: non_neg_integer(), 
-			 kind :: 'var' | 'reg' | 'fvar',
-			 annotation = [] :: [] | variable_annotation()}). 
+-record(icode_variable, {name :: non_neg_integer(),
+			 kind :: 'var' | 'reg' | 'reg_gcsafe' | 'fvar',
+			 annotation = [] :: [] | variable_annotation()}).
 
 %%---------------------------------------------------------------------
 %% Type declarations for Icode instructions
@@ -66,7 +66,7 @@
 -type icode_funcall()   :: mfa() | icode_primop().
 
 -type icode_var()	:: #icode_variable{kind::'var'}.
--type icode_reg()	:: #icode_variable{kind::'reg'}.
+-type icode_reg()	:: #icode_variable{kind::'reg'|'reg_gcsafe'}.
 -type icode_fvar()	:: #icode_variable{kind::'fvar'}.
 -type icode_argument()	:: #icode_const{} | #icode_variable{}.
 -type icode_term_arg()	:: icode_var() | #icode_const{}.
diff --git a/lib/hipe/icode/hipe_icode_liveness.erl b/lib/hipe/icode/hipe_icode_liveness.erl
index 51e2855108..e61529a1bb 100644
--- a/lib/hipe/icode/hipe_icode_liveness.erl
+++ b/lib/hipe/icode/hipe_icode_liveness.erl
@@ -77,6 +77,7 @@ print_var(#icode_variable{name=V, kind=Kind, annotation=T}) ->
   case Kind of
     var -> io:format("v~p", [V]);
     reg -> io:format("r~p", [V]);
+    reg_gcsafe -> io:format("rs~p", [V]);
     fvar -> io:format("fv~p", [V])
   end,
   case T of
diff --git a/lib/hipe/icode/hipe_icode_pp.erl b/lib/hipe/icode/hipe_icode_pp.erl
index 5b017dca32..33d1e62884 100644
--- a/lib/hipe/icode/hipe_icode_pp.erl
+++ b/lib/hipe/icode/hipe_icode_pp.erl
@@ -230,7 +230,10 @@ pp_arg(Dev, Arg) ->
 	  case hipe_icode:is_reg(Arg) of
 	    true ->
 	      N = hipe_icode:reg_name(Arg),
-	      io:format(Dev, "r~p", [N]);
+	      case hipe_icode:reg_is_gcsafe(Arg) of
+		true  -> io:format(Dev, "rs~p", [N]);
+		false -> io:format(Dev, "r~p", [N])
+	      end;
 	    false ->
 	      N = hipe_icode:fvar_name(Arg),
 	      io:format(Dev, "fv~p", [N])
diff --git a/lib/hipe/icode/hipe_icode_primops.erl b/lib/hipe/icode/hipe_icode_primops.erl
index 50ece05259..941516e8b1 100644
--- a/lib/hipe/icode/hipe_icode_primops.erl
+++ b/lib/hipe/icode/hipe_icode_primops.erl
@@ -67,6 +67,8 @@ is_safe(fp_mul) -> false;
 is_safe(fp_sub) -> false;
 is_safe(mktuple) -> true;
 is_safe(next_msg) -> false;
+is_safe(recv_mark) -> false;
+is_safe(recv_set) -> false;
 is_safe(redtest) -> false;
 is_safe(select_msg) -> false;
 is_safe(self) -> true;
@@ -130,6 +132,7 @@ is_safe({hipe_bs_primop, {bs_match_string, _, _}}) -> false;
 is_safe({hipe_bs_primop, {bs_append, _, _, _, _}}) -> false;
 is_safe({hipe_bs_primop, {bs_private_append, _, _}}) -> false;
 is_safe({hipe_bs_primop, bs_init_writable}) -> true;
+is_safe(build_stacktrace) -> true;
 is_safe(#mkfun{}) -> true;
 is_safe(#unsafe_element{}) -> true;
 is_safe(#unsafe_update_element{}) -> true;
@@ -165,6 +168,8 @@ fails(fp_mul) -> false;
 fails(fp_sub) -> false;
 fails(mktuple) -> false;
 fails(next_msg) -> false;
+fails(recv_mark) -> false;
+fails(recv_set) -> false;
 fails(redtest) -> false;
 fails(select_msg) -> false;
 fails(self) -> false;
@@ -230,6 +235,7 @@ fails({hipe_bs_primop, bs_final}) -> false;
 fails({hipe_bs_primop, {bs_append, _, _, _, _}}) -> true;
 fails({hipe_bs_primop, {bs_private_append, _, _}}) -> true;
 fails({hipe_bs_primop, bs_init_writable}) -> true;
+fails(build_stacktrace) -> false;
 fails(#mkfun{}) -> false;
 fails(#unsafe_element{}) -> false;
 fails(#unsafe_update_element{}) -> false;
@@ -709,6 +715,10 @@ type(Primop, Args) ->
       erl_types:t_any();
     next_msg ->
       erl_types:t_any();
+    recv_mark ->
+      erl_types:t_any();
+    recv_set ->
+      erl_types:t_any();
     select_msg ->
       erl_types:t_any();
     set_timeout ->
@@ -723,6 +733,8 @@ type(Primop, Args) ->
       erl_types:t_any();
     debug_native_called ->
       erl_types:t_any();
+    build_stacktrace ->
+      erl_types:t_list();
     {M, F, A} ->
       erl_bif_types:type(M, F, A, Args)
   end.
@@ -883,6 +895,10 @@ type(Primop) ->
       erl_types:t_any();
     next_msg ->
       erl_types:t_any();
+    recv_mark ->
+      erl_types:t_any();
+    recv_set ->
+      erl_types:t_any();
     select_msg ->
       erl_types:t_any();
     set_timeout ->
@@ -891,6 +907,8 @@ type(Primop) ->
       erl_types:t_any();
 %%% -----------------------------------------------------
 %%% Other
+    build_stacktrace ->
+      erl_types:t_any();
     #closure_element{} ->
       erl_types:t_any();
     redtest ->
diff --git a/lib/hipe/icode/hipe_icode_range.erl b/lib/hipe/icode/hipe_icode_range.erl
index 287b1c80fe..cf74c1eb5b 100644
--- a/lib/hipe/icode/hipe_icode_range.erl
+++ b/lib/hipe/icode/hipe_icode_range.erl
@@ -1160,6 +1160,8 @@ basic_type(#gc_test{}) -> not_analysed;
 %% Message handling
 basic_type(check_get_msg) -> not_analysed;
 basic_type(next_msg) -> not_analysed;
+basic_type(recv_mark) -> not_analysed;
+basic_type(recv_set) -> not_analysed;
 basic_type(select_msg) -> not_analysed;
 basic_type(suspend_msg) -> not_analysed;
 %% Functions
@@ -1184,7 +1186,8 @@ basic_type(unsafe_hd) -> not_analysed;
 basic_type(unsafe_tl) -> not_int;
 basic_type(#element{}) -> not_analysed;
 basic_type(#unsafe_element{}) -> not_analysed;
-basic_type(#unsafe_update_element{}) -> not_analysed.
+basic_type(#unsafe_update_element{}) -> not_analysed;
+basic_type(build_stacktrace) -> not_int.
 
 -spec analyse_bs_get_integer(integer(), integer(), boolean()) -> range_tuple().
 
diff --git a/lib/hipe/llvm/hipe_llvm.erl b/lib/hipe/llvm/hipe_llvm.erl
index 641d3fda0a..ccd40162cb 100644
--- a/lib/hipe/llvm/hipe_llvm.erl
+++ b/lib/hipe/llvm/hipe_llvm.erl
@@ -1005,11 +1005,12 @@ pp_ins(Dev, Ver, I) ->
       write(Dev, [" ", adj_stack_offset(I),")\n"]);
     #llvm_meta{} ->
       write(Dev, ["!", meta_id(I), " = !{ "]),
-      write(Dev, string:join([if is_list(Op) -> ["!\"", Op, "\""];
-				 is_integer(Op) -> ["i32 ", integer_to_list(Op)];
-				 is_record(Op, llvm_meta) ->
-				  ["!", meta_id(Op)]
-			      end || Op <- meta_operands(I)], ", ")),
+      write(Dev, lists:join(", ",
+                            [if is_list(Op) -> ["!\"", Op, "\""];
+                                is_integer(Op) -> ["i32 ", integer_to_list(Op)];
+                                is_record(Op, llvm_meta) ->
+                                 ["!", meta_id(Op)]
+                             end || Op <- meta_operands(I)])),
       write(Dev, " }\n");
     Other ->
       exit({?MODULE, pp_ins, {"Unknown LLVM instruction", Other}})
diff --git a/lib/hipe/llvm/hipe_llvm_main.erl b/lib/hipe/llvm/hipe_llvm_main.erl
index 4eec0c752b..54c435c127 100644
--- a/lib/hipe/llvm/hipe_llvm_main.erl
+++ b/lib/hipe/llvm/hipe_llvm_main.erl
@@ -154,7 +154,7 @@ compiler_target_opt() ->
 
 %% @doc Join options.
 fix_opts(Opts) ->
-  string:join(Opts, " ").
+  lists:flatten(lists:join(" ", Opts)).
 
 %% @doc Translate optimization-level flag (default is "O2").
 trans_optlev_flag(Tool, Options) ->
diff --git a/lib/hipe/llvm/hipe_rtl_to_llvm.erl b/lib/hipe/llvm/hipe_rtl_to_llvm.erl
index 79e1bfd381..934717efc1 100644
--- a/lib/hipe/llvm/hipe_rtl_to_llvm.erl
+++ b/lib/hipe/llvm/hipe_rtl_to_llvm.erl
@@ -1537,7 +1537,7 @@ declare_switch_table({Name, {switch, {TableType, Labels, _, _}, _}}, FunName) ->
   LabelList = [mk_jump_label(L) || L <- Labels],
   Fun1 = fun(X) -> "i8* blockaddress(@" ++ FunName ++ ", " ++ X ++ ")" end,
   List2 = lists:map(Fun1, LabelList),
-  List3 = string:join(List2, ",\n"),
+  List3 = lists:flatten(lists:join(",\n", List2)),
   List4 = "[\n" ++ List3 ++ "\n]\n",
   hipe_llvm:mk_const_decl("@" ++ Name, "constant", TableType, List4).
 
@@ -1553,7 +1553,7 @@ declare_closure_labels(ClosureLabels, Relocs, Fun) ->
   Relocs1 = relocs_store("table_closures", {table_closures, ArityList}, Relocs),
   List2 =
     ["i8* blockaddress(@" ++ FunName ++ ", " ++ L ++ ")" || L <- LabelList],
-  List3 = string:join(List2, ",\n"),
+  List3 = lists:flatten(lists:join(",\n", List2)),
   List4 = "[\n" ++ List3 ++ "\n]\n",
   NrLabels = length(LabelList),
   ByteTyPtr = hipe_llvm:mk_pointer(hipe_llvm:mk_int(?BITS_IN_BYTE)),
diff --git a/lib/hipe/main/hipe.app.src b/lib/hipe/main/hipe.app.src
index fb750dd418..66008a4178 100644
--- a/lib/hipe/main/hipe.app.src
+++ b/lib/hipe/main/hipe.app.src
@@ -179,6 +179,7 @@
 	     hipe_rtl_to_sparc,
 	     hipe_rtl_to_x86,
 	     hipe_rtl_varmap,
+	     hipe_rtl_verify_gcsafe,
 	     hipe_segment_trees,
 	     hipe_sdi,
 	     hipe_sparc,
diff --git a/lib/hipe/main/hipe.erl b/lib/hipe/main/hipe.erl
index 19b4e8bfe2..acb9b7b062 100644
--- a/lib/hipe/main/hipe.erl
+++ b/lib/hipe/main/hipe.erl
@@ -1414,6 +1414,7 @@ opt_keys() ->
      use_clusters,
      use_jumptable,
      verbose,
+     verify_gcsafe,
      %% verbose_spills,
      x87].
 
@@ -1510,7 +1511,8 @@ opt_negations() ->
    {no_use_callgraph, use_callgraph},
    {no_use_clusters, use_clusters},
    {no_use_inline_atom_search, use_inline_atom_search},
-   {no_use_indexing, use_indexing}].
+   {no_use_indexing, use_indexing},
+   {no_verify_gcsafe, verify_gcsafe}].
 
 %% Don't use negative forms in right-hand sides of aliases and expansions!
 %% We only expand negations once, before the other expansions are done.
@@ -1616,11 +1618,11 @@ llvm_support_available() ->
 get_llvm_version() ->
   OptStr = os:cmd("opt -version"),
   SubStr = "LLVM version ", N = length(SubStr),
-  case string:str(OptStr, SubStr) of
-     0 -> % No opt available
+  case string:find(OptStr, SubStr) of
+     nomatch -> % No opt available
        {0, 0};
      S ->
-       case string:tokens(string:sub_string(OptStr, S + N), ".") of
+       case string:lexemes(string:slice(S, N), ".") of
 	 [MajorS, MinorS | _] ->
 	   case {string:to_integer(MajorS), string:to_integer(MinorS)} of
 	     {{Major, ""}, {Minor, _}}
diff --git a/lib/hipe/main/hipe_main.erl b/lib/hipe/main/hipe_main.erl
index dca6fddec3..4b5eb4c63e 100644
--- a/lib/hipe/main/hipe_main.erl
+++ b/lib/hipe/main/hipe_main.erl
@@ -410,6 +410,11 @@ icode_to_rtl(MFA, Icode, Options, Servers) ->
         hipe_llvm_liveness:analyze(RtlCfg4)
     end,
   pp(RtlCfg5, MFA, rtl, pp_rtl, Options, Servers),
+  case proplists:get_bool(verify_gcsafe, Options) of
+    false -> ok;
+    true ->
+      ok = hipe_rtl_verify_gcsafe:check(RtlCfg5)
+  end,
   LinearRTL1 = hipe_rtl_cfg:linearize(RtlCfg5),
   LinearRTL2 = hipe_rtl_cleanup_const:cleanup(LinearRTL1),
   %% hipe_rtl:pp(standard_io, LinearRTL2),
diff --git a/lib/hipe/rtl/Makefile b/lib/hipe/rtl/Makefile
index 5abc9ec049..becdd0b7d8 100644
--- a/lib/hipe/rtl/Makefile
+++ b/lib/hipe/rtl/Makefile
@@ -50,7 +50,7 @@ HIPE_MODULES = hipe_rtl hipe_rtl_cfg \
 	  hipe_rtl_ssa hipe_rtl_ssa_const_prop \
 	  hipe_rtl_cleanup_const hipe_rtl_symbolic hipe_rtl_lcm \
 	  hipe_rtl_ssapre hipe_rtl_binary hipe_rtl_ssa_avail_expr \
-	  hipe_rtl_arch hipe_tagscheme
+	  hipe_rtl_arch hipe_tagscheme hipe_rtl_verify_gcsafe
 else
 HIPE_MODULES =
 endif
diff --git a/lib/hipe/rtl/hipe_rtl.erl b/lib/hipe/rtl/hipe_rtl.erl
index 04c9728d5c..33027f3259 100644
--- a/lib/hipe/rtl/hipe_rtl.erl
+++ b/lib/hipe/rtl/hipe_rtl.erl
@@ -1740,7 +1740,10 @@ pp_reg(Dev, Arg) ->
     true ->
       pp_hard_reg(Dev, reg_index(Arg));
     false ->
-      io:format(Dev, "r~w", [reg_index(Arg)])
+      case reg_is_gcsafe(Arg) of
+        true -> io:format(Dev, "rs~w", [reg_index(Arg)]);
+        false -> io:format(Dev, "r~w", [reg_index(Arg)])
+      end
   end.
 
 pp_var(Dev, Arg) ->
diff --git a/lib/hipe/rtl/hipe_rtl_binary_construct.erl b/lib/hipe/rtl/hipe_rtl_binary_construct.erl
index bc215e3abe..5b89d4946a 100644
--- a/lib/hipe/rtl/hipe_rtl_binary_construct.erl
+++ b/lib/hipe/rtl/hipe_rtl_binary_construct.erl
@@ -359,7 +359,8 @@ not_writable_code(Bin, SizeReg, Dst, Base, Offset, Unit,
 allocate_writable(Dst, Base, UsedBytes, TotBytes, TotSize) ->
   Zero = hipe_rtl:mk_imm(0),
   [NextLbl] = create_lbls(1),
-  [EndSubSize, EndSubBitSize, ProcBin] = create_regs(3),
+  [EndSubSize, EndSubBitSize] = create_regs(2),
+  [ProcBin] = create_unsafe_regs(1),
   [hipe_rtl:mk_call([Base], bs_allocate, [UsedBytes],
 		    hipe_rtl:label_name(NextLbl), [], not_remote),
    NextLbl,
@@ -586,12 +587,12 @@ const_init2(Size, Dst, Base, Offset, TrueLblName) ->
     false ->
       ByteSize = hipe_rtl:mk_new_reg(),
       [hipe_rtl:mk_gctest(?PROC_BIN_WORDSIZE+?SUB_BIN_WORDSIZE),
-       hipe_rtl:mk_move(Offset, hipe_rtl:mk_imm(0)),
        hipe_rtl:mk_move(ByteSize, hipe_rtl:mk_imm(Size)),
        hipe_rtl:mk_call([Base], bs_allocate, [ByteSize],
 			hipe_rtl:label_name(NextLbl), [], not_remote),
        NextLbl,
        hipe_tagscheme:create_refc_binary(Base, ByteSize, Dst),
+       hipe_rtl:mk_move(Offset, hipe_rtl:mk_imm(0)),
        hipe_rtl:mk_goto(TrueLblName)]
   end.
 
@@ -634,13 +635,12 @@ var_init2(Size, Dst, Base, Offset, TrueLblName, SystemLimitLblName, FalseLblName
   Log2WordSize = hipe_rtl_arch:log2_word_size(),
   WordSize = hipe_rtl_arch:word_size(),
   [ContLbl, HeapLbl, REFCLbl, NextLbl] = create_lbls(4),
-  [USize, Tmp] = create_unsafe_regs(2),
+  [USize, Tmp] = create_regs(2),
   [get_word_integer(Size, USize, SystemLimitLblName, FalseLblName),
    hipe_rtl:mk_branch(USize, leu, hipe_rtl:mk_imm(?MAX_BINSIZE),
 		      hipe_rtl:label_name(ContLbl),
 		      SystemLimitLblName),
    ContLbl,
-   hipe_rtl:mk_move(Offset, hipe_rtl:mk_imm(0)),
    hipe_rtl:mk_branch(USize, leu, hipe_rtl:mk_imm(?MAX_HEAP_BIN_SIZE),
 		      hipe_rtl:label_name(HeapLbl),
 		      hipe_rtl:label_name(REFCLbl)),
@@ -650,6 +650,7 @@ var_init2(Size, Dst, Base, Offset, TrueLblName, SystemLimitLblName, FalseLblName
    hipe_rtl:mk_alu(Tmp, Tmp, add, hipe_rtl:mk_imm(?SUB_BIN_WORDSIZE)),
    hipe_rtl:mk_gctest(Tmp),
    hipe_tagscheme:create_heap_binary(Base, USize, Dst),
+   hipe_rtl:mk_move(Offset, hipe_rtl:mk_imm(0)),
    hipe_rtl:mk_goto(TrueLblName),
    REFCLbl,
    hipe_rtl:mk_gctest(?PROC_BIN_WORDSIZE+?SUB_BIN_WORDSIZE),
@@ -657,6 +658,7 @@ var_init2(Size, Dst, Base, Offset, TrueLblName, SystemLimitLblName, FalseLblName
 		    hipe_rtl:label_name(NextLbl), [], not_remote),
    NextLbl,
    hipe_tagscheme:create_refc_binary(Base, USize, Dst),
+   hipe_rtl:mk_move(Offset, hipe_rtl:mk_imm(0)),
    hipe_rtl:mk_goto(TrueLblName)].
 
 var_init_bits(Size, Dst, Base, Offset, TrueLblName, SystemLimitLblName, FalseLblName) ->
@@ -863,7 +865,7 @@ get_base_offset_size(Binary, SrcBase, SrcOffset, SrcSize, FLName) ->
    JoinLbl,
    hipe_tagscheme:test_heap_binary(Orig, HeapLblName, REFCLblName),
    HeapLbl,
-   hipe_rtl:mk_alu(SrcBase, Orig, add, hipe_rtl:mk_imm(?HEAP_BIN_DATA-2)),
+   hipe_tagscheme:get_field_addr_from_term({heap_bin, {data, 0}}, Orig, SrcBase),
    hipe_rtl:mk_goto(EndLblName),
    REFCLbl,
    hipe_tagscheme:get_field_from_term({proc_bin,bytes}, Orig, SrcBase),
@@ -1210,6 +1212,12 @@ is_divisible(Dividend, Divisor, SuccLbl, FailLbl) ->
       [hipe_rtl:mk_branch(Dividend, 'and', Mask, eq, SuccLbl, FailLbl, 0.99)];
     false ->
       %% We need division, fall back to a primop
-      [hipe_rtl:mk_call([], is_divisible, [Dividend, hipe_rtl:mk_imm(Divisor)],
-			SuccLbl, FailLbl, not_remote)]
+      [Tmp] = create_regs(1),
+      RetLbl = hipe_rtl:mk_new_label(),
+      [hipe_rtl:mk_call([Tmp], is_divisible,
+                        [Dividend, hipe_rtl:mk_imm(Divisor)],
+                        hipe_rtl:label_name(RetLbl), [], not_remote),
+       RetLbl,
+       hipe_rtl:mk_branch(Tmp, ne, hipe_rtl:mk_imm(0),
+                          SuccLbl, FailLbl, 0.99)]
   end.
diff --git a/lib/hipe/rtl/hipe_rtl_binary_match.erl b/lib/hipe/rtl/hipe_rtl_binary_match.erl
index 362a52f8fe..4575213838 100644
--- a/lib/hipe/rtl/hipe_rtl_binary_match.erl
+++ b/lib/hipe/rtl/hipe_rtl_binary_match.erl
@@ -730,7 +730,7 @@ get_base(Orig,Base) ->
   [hipe_tagscheme:test_heap_binary(Orig, hipe_rtl:label_name(HeapLbl),
 				   hipe_rtl:label_name(REFCLbl)),
    HeapLbl,
-   hipe_rtl:mk_alu(Base, Orig, 'add', hipe_rtl:mk_imm(?HEAP_BIN_DATA-2)),
+   hipe_tagscheme:get_field_addr_from_term({heap_bin, {data, 0}}, Orig, Base),
    hipe_rtl:mk_goto(hipe_rtl:label_name(EndLbl)),
    REFCLbl,
    get_field_from_term({proc_bin, flags}, Orig, Flags),
@@ -740,7 +740,7 @@ get_base(Orig,Base) ->
    WritableLbl,
    hipe_rtl:mk_call([], emasculate_binary, [Orig], [], [], 'not_remote'),
    NotWritableLbl,
-   hipe_rtl:mk_load(Base, Orig, hipe_rtl:mk_imm(?PROC_BIN_BYTES-2)),
+   get_field_from_term({proc_bin, bytes}, Orig, Base),
    EndLbl].
 
 extract_matchstate_var(binsize, Ms) ->
@@ -842,12 +842,12 @@ make_dyn_prep(SizeReg, CCode) ->
 %%------------------------------------------------------------------------
 
 get_unaligned_int(Dst1, Size, Base, Offset, Shiftr, Type, TrueLblName) ->
-  [Reg] = create_regs(1),
+  [Reg] = create_gcsafe_regs(1),
   [get_maybe_unaligned_int_to_reg(Reg, Size, Base, Offset, Shiftr, Type),
    do_bignum_code(Size, Type, Reg, Dst1, TrueLblName)].
 
 get_maybe_unaligned_int_to_reg(Reg, Size, Base, Offset, Shiftr, Type) ->
-  [LowBits] = create_regs(1),
+  [LowBits] = create_gcsafe_regs(1),
   [AlignedLbl, UnAlignedLbl, EndLbl] = create_lbls(3),
   [hipe_rtl:mk_alub(LowBits, Offset, 'and', hipe_rtl:mk_imm(?LOW_BITS),
 		    eq, hipe_rtl:label_name(AlignedLbl), 
@@ -1001,7 +1001,7 @@ do_bignum_code(Size, {Signedness,_}, Src, Dst1, TrueLblName)
     end.
 
 signed_bignum(Dst1, Src, TrueLblName) ->
-  Tmp1 = hipe_rtl:mk_new_reg(),
+  Tmp1 = hipe_rtl:mk_new_reg_gcsafe(),
   BignumLabel = hipe_rtl:mk_new_label(),
   [hipe_tagscheme:realtag_fixnum(Dst1, Src),
    hipe_tagscheme:realuntag_fixnum(Tmp1, Dst1),
diff --git a/lib/hipe/rtl/hipe_rtl_cleanup_const.erl b/lib/hipe/rtl/hipe_rtl_cleanup_const.erl
index bfa6b9682e..00cc2bcb37 100644
--- a/lib/hipe/rtl/hipe_rtl_cleanup_const.erl
+++ b/lib/hipe/rtl/hipe_rtl_cleanup_const.erl
@@ -69,9 +69,9 @@ cleanup_instr([Const|Left], I, Acc) ->
   case I of
     X when is_record(X, fp_unop) orelse is_record(X, fp) ->
       Fdst = hipe_rtl:mk_new_fpreg(),
-      Fconv = hipe_tagscheme:unsafe_untag_float(Fdst, Dst),		  
+      Fconv = lists:flatten(hipe_tagscheme:unsafe_untag_float(Fdst, Dst)),
       NewI = hipe_rtl:subst_uses([{Const, Fdst}], I),
-      cleanup_instr(Left, NewI, Fconv ++ [Load|Acc]);
+      cleanup_instr(Left, NewI, lists:reverse(Fconv, [Load|Acc]));
     _ ->
       NewI = hipe_rtl:subst_uses([{Const, Dst}], I),
       cleanup_instr(Left, NewI, [Load|Acc])
diff --git a/lib/hipe/rtl/hipe_rtl_lcm.erl b/lib/hipe/rtl/hipe_rtl_lcm.erl
index 9dcdd05fb1..af39c9a0a4 100644
--- a/lib/hipe/rtl/hipe_rtl_lcm.erl
+++ b/lib/hipe/rtl/hipe_rtl_lcm.erl
@@ -182,42 +182,41 @@ delete_exprs(Code, _, _, []) ->
   Code;
 delete_exprs(Code, ExprMap, IdMap, [ExprId|Exprs]) ->
   Expr = expr_id_map_get_expr(IdMap, ExprId),
-  %% Perform a foldl that goes through the code and deletes all
-  %% occurences of the expression.
-  NewCode =
-    lists:reverse
-      (lists:foldl(fun(CodeExpr, Acc) ->
-                     case is_expr(CodeExpr) of
-                       true ->
-                         case expr_clear_dst(CodeExpr) =:= Expr of
-                           true ->
-                             pp_debug("  Deleting:         ", []),
-                             pp_debug_instr(CodeExpr),
-                             %% Lookup expression entry.
-                             Defines = 
-                               case expr_map_lookup(ExprMap, Expr) of
-                                 {value, {_, _, Defs}} -> 
-				   Defs;
-                                 none -> 
-                                   exit({?MODULE, expr_map_lookup,
-                                         "expression missing"})
-                               end,
-                             MoveCode = 
-                               mk_expr_move_instr(hipe_rtl:defines(CodeExpr),
-						  Defines),
-                             pp_debug("    Replacing with: ", []),
-                             pp_debug_instr(MoveCode),
-                             [MoveCode|Acc];
-                           false ->
-                             [CodeExpr|Acc]
-                         end;
-		       false ->
-                             [CodeExpr|Acc]
-                     end
-                   end, 
-		   [], Code)),
+  %% Lookup expression entry.
+  {value, {_, _, Defines}} = expr_map_lookup(ExprMap, Expr),
+  %% Go through the code and deletes all occurences of the expression.
+  NewCode = delete_expr(Code, Expr, Defines, []),
   delete_exprs(NewCode, ExprMap, IdMap, Exprs).
 
+delete_expr([], _Expr, _Defines, Acc) -> lists:reverse(Acc);
+delete_expr([CodeExpr|Code], Expr, Defines, Acc) ->
+  case exp_kill_expr(CodeExpr, [Expr]) of
+    [] -> % Expr was killed; deleting stops here
+      pp_debug("  Stopping before:  ", []),
+      pp_debug_instr(CodeExpr),
+      lists:reverse(Acc, [CodeExpr|Code]);
+    [Expr] ->
+      NewCodeExpr =
+        case is_expr(CodeExpr) of
+          true ->
+            case expr_clear_dst(CodeExpr) =:= Expr of
+              true ->
+                pp_debug("  Deleting:         ", []),
+                pp_debug_instr(CodeExpr),
+                MoveCode = mk_expr_move_instr(hipe_rtl:defines(CodeExpr),
+                                              Defines),
+                pp_debug("    Replacing with: ", []),
+                pp_debug_instr(MoveCode),
+                MoveCode;
+              false ->
+                CodeExpr
+            end;
+          false ->
+            CodeExpr
+        end,
+      delete_expr(Code, Expr, Defines, [NewCodeExpr|Acc])
+  end.
+
 %%=============================================================================
 %% Goes through the given list of expressions and inserts them at 
 %% appropriate places in the code.
@@ -226,13 +225,12 @@ insert_exprs(CFG, _, _, _, _, BetweenMap, []) ->
 insert_exprs(CFG, Pred, Succ, ExprMap, IdMap, BetweenMap, [ExprId|Exprs]) ->
   Expr = expr_id_map_get_expr(IdMap, ExprId),
   Instr = expr_map_get_instr(ExprMap, Expr),
-  case hipe_rtl_cfg:succ(CFG, Pred) of
-    [_] ->
+  case try_insert_expr_last(CFG, Pred, Instr) of
+    {ok, NewCFG} ->
       pp_debug("  Inserted last: ", []),
       pp_debug_instr(Instr),
-      NewCFG = insert_expr_last(CFG, Pred, Instr),
       insert_exprs(NewCFG, Pred, Succ, ExprMap, IdMap, BetweenMap, Exprs);
-    _ ->
+    not_safe ->
       case hipe_rtl_cfg:pred(CFG, Succ) of
         [_] ->
 	  pp_debug("  Inserted first: ", []),
@@ -252,25 +250,31 @@ insert_exprs(CFG, Pred, Succ, ExprMap, IdMap, BetweenMap, [ExprId|Exprs]) ->
 %% Recursively goes through the code in a block and returns a new block
 %% with the new code inserted second to last (assuming the last expression
 %% is a branch operation).
-insert_expr_last(CFG0, Label, Instr) ->
-  Code0 = hipe_bb:code(hipe_rtl_cfg:bb(CFG0, Label)),
-  %% FIXME: Use hipe_bb:butlast() instead?
-  Code1 = insert_expr_last_work(Label, Instr, Code0),
-  hipe_rtl_cfg:bb_add(CFG0, Label, hipe_bb:mk_bb(Code1)).
+try_insert_expr_last(CFG0, Label, Instr) ->
+  case hipe_rtl_cfg:succ(CFG0, Label) of
+    [_] ->
+      Code0 = hipe_bb:code(hipe_rtl_cfg:bb(CFG0, Label)),
+      case insert_expr_last_work(Instr, Code0) of
+        not_safe -> not_safe;
+        Code1 ->
+          {ok, hipe_rtl_cfg:bb_add(CFG0, Label, hipe_bb:mk_bb(Code1))}
+      end;
+    _ -> not_safe
+  end.
 
 %%=============================================================================
 %% Recursively goes through the code in a block and returns a new block
 %% with the new code inserted second to last (assuming the last expression
 %% is a branch operation).
-insert_expr_last_work(_, Instr, []) ->
-  %% This case should not happen since this means that block was completely 
-  %% empty when the function was called. For compatibility we insert it last.
-  [Instr];
-insert_expr_last_work(_, Instr, [Code1]) ->
+insert_expr_last_work(_Instr, [#call{}]) ->
+  %% Call instructions clobber all expressions; we musn't insert the expression
+  %% before it
+  not_safe;
+insert_expr_last_work(Instr, [Code1]) ->
   %% We insert the code next to last.
   [Instr, Code1];
-insert_expr_last_work(Label, Instr, [Code|Codes]) ->
-  [Code|insert_expr_last_work(Label, Instr, Codes)].
+insert_expr_last_work(Instr, [Code|Codes]) ->
+  [Code|insert_expr_last_work(Instr, Codes)].
 
 %%=============================================================================
 %% Inserts expression first in the block for the given label.
@@ -305,7 +309,8 @@ insert_expr_between(CFG0, BetweenMap, Pred, Succ, Instr) ->
     {value, Label} ->
       pp_debug("    Using existing new bb for edge (~w,~w) with label ~w~n", 
 	       [Pred, Succ, Label]),
-      {insert_expr_last(CFG0, Label, Instr), BetweenMap}
+      {ok, NewCfg} = try_insert_expr_last(CFG0, Label, Instr),
+      {NewCfg, BetweenMap}
   end.
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
diff --git a/lib/hipe/rtl/hipe_rtl_primops.erl b/lib/hipe/rtl/hipe_rtl_primops.erl
index 850a75f71b..d646b78a3d 100644
--- a/lib/hipe/rtl/hipe_rtl_primops.erl
+++ b/lib/hipe/rtl/hipe_rtl_primops.erl
@@ -291,6 +291,10 @@ gen_primop({Op,Dst,Args,Cont,Fail}, IsGuard, ConstTab) ->
 	    gen_select_msg(Dst, Cont);
 	  clear_timeout ->
 	    gen_clear_timeout(Dst, GotoCont);
+          recv_mark ->
+            gen_recv_mark(Dst, GotoCont);
+	  recv_set ->
+            gen_recv_set(Dst, Cont);
 	  set_timeout ->
 	    %% BIF call: am_set_timeout -> nbif_set_timeout -> hipe_set_timeout
 	    [hipe_rtl:mk_call(Dst, set_timeout, Args, Cont, Fail, not_remote)];
@@ -390,6 +394,8 @@ gen_primop({Op,Dst,Args,Cont,Fail}, IsGuard, ConstTab) ->
 	    end;
 	  debug_native_called -> 
 	    [hipe_rtl:mk_call(Dst, Op, Args, Cont, Fail, not_remote)];
+          build_stacktrace ->
+	    [hipe_rtl:mk_call(Dst, Op, Args, Cont, Fail, not_remote)];
 
 	  %% Only names listed above are accepted! MFA:s are not primops!
 	  _ ->
@@ -1064,6 +1070,27 @@ gen_tuple_header(Ptr, Arity) ->
 %%%
 %%% Receives
 
+%%% recv_mark is:
+%%%	p->msg.saved_last = p->msg.last;
+gen_recv_mark([], GotoCont) ->
+  TmpLast = hipe_rtl:mk_new_reg(),
+  [load_p_field(TmpLast, ?P_MSG_LAST),
+   store_p_field(TmpLast, ?P_MSG_SAVED_LAST),
+   GotoCont].
+
+%%% recv_set is:
+%%%	if (p->msg.saved_last)
+%%%	    p->msg.save = p->msg.saved_last;
+gen_recv_set([], Cont) ->
+  TmpSave = hipe_rtl:mk_new_reg(),
+  TrueLbl = hipe_rtl:mk_new_label(),
+  [load_p_field(TmpSave, ?P_MSG_SAVED_LAST),
+   hipe_rtl:mk_branch(TmpSave, ne, hipe_rtl:mk_imm(0),
+                      hipe_rtl:label_name(TrueLbl), Cont),
+   TrueLbl,
+   store_p_field(TmpSave, ?P_MSG_SAVE),
+   hipe_rtl:mk_goto(Cont)].
+
 gen_check_get_msg(Dsts, GotoCont, Fail) ->
   gen_check_get_msg_outofline(Dsts, GotoCont, Fail).
 
diff --git a/lib/hipe/rtl/hipe_rtl_varmap.erl b/lib/hipe/rtl/hipe_rtl_varmap.erl
index 375a8f85c0..f34c66ab85 100644
--- a/lib/hipe/rtl/hipe_rtl_varmap.erl
+++ b/lib/hipe/rtl/hipe_rtl_varmap.erl
@@ -105,7 +105,7 @@ icode_var2rtl_var(Var, Map) ->
 	{reg, IsGcSafe} ->
 	  NewVar =
 	    case IsGcSafe of
-	      %% true -> hipe_rtl:mk_new_reg_gcsafe();
+              true -> hipe_rtl:mk_new_reg_gcsafe();
 	      false -> hipe_rtl:mk_new_reg()
 	    end,
 	  {NewVar, insert(Var, NewVar, Map)}
diff --git a/lib/hipe/rtl/hipe_rtl_verify_gcsafe.erl b/lib/hipe/rtl/hipe_rtl_verify_gcsafe.erl
new file mode 100644
index 0000000000..c3f20bfec1
--- /dev/null
+++ b/lib/hipe/rtl/hipe_rtl_verify_gcsafe.erl
@@ -0,0 +1,88 @@
+%% -*- mode: erlang; erlang-indent-level: 2 -*-
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+-module(hipe_rtl_verify_gcsafe).
+
+-export([check/1]).
+
+-include("../flow/cfg.hrl").              %% needed for the specs
+-include("hipe_rtl.hrl").
+
+check(CFG) ->
+  Liveness = hipe_rtl_liveness:analyze(CFG),
+  put({?MODULE, 'fun'}, CFG#cfg.info#cfg_info.'fun'),
+  lists:foreach(
+    fun(Lb) ->
+        put({?MODULE, label}, Lb),
+        Liveout = hipe_rtl_liveness:liveout(Liveness, Lb),
+        BB = hipe_rtl_cfg:bb(CFG, Lb),
+        check_instrs(lists:reverse(hipe_bb:code(BB)), Liveout)
+    end, hipe_rtl_cfg:labels(CFG)),
+  erase({?MODULE, 'fun'}),
+  erase({?MODULE, label}),
+  erase({?MODULE, instr}),
+  ok.
+
+check_instrs([], _Livein) -> ok;
+check_instrs([I|Is], LiveOut) ->
+  Def = ordsets:from_list(hipe_rtl:defines(I)),
+  Use = ordsets:from_list(hipe_rtl:uses(I)),
+  LiveOver = ordsets:subtract(LiveOut, Def),
+  LiveIn = ordsets:union(LiveOver, Use),
+  case (hipe_rtl:is_call(I)
+        andalso not safe_primop(hipe_rtl:call_fun(I)))
+    orelse is_record(I, gctest)
+  of
+    false -> ok;
+    true ->
+      put({?MODULE, instr}, I),
+      lists:foreach(fun verify_live/1, LiveOver)
+  end,
+  check_instrs(Is, LiveIn).
+
+verify_live(T) ->
+  case hipe_rtl:is_reg(T) of
+    false -> ok;
+    true ->
+      case hipe_rtl:reg_is_gcsafe(T) of
+        true -> ok;
+        false ->
+          error({gcunsafe_live_over_call,
+                 get({?MODULE, 'fun'}),
+                 {label, get({?MODULE, label})},
+                 get({?MODULE, instr}),
+                 T})
+      end
+  end.
+
+%% Primops that can't gc
+%% Note: This information is essentially duplicated from hipe_bif_list.m4
+safe_primop(is_divisible) -> true;
+safe_primop(is_unicode) -> true;
+safe_primop(cmp_2) -> true;
+safe_primop(eq_2) -> true;
+safe_primop(bs_allocate) -> true;
+safe_primop(bs_reallocate) -> true;
+safe_primop(bs_utf8_size) -> true;
+safe_primop(bs_get_utf8) -> true;
+safe_primop(bs_utf16_size) -> true;
+safe_primop(bs_get_utf16) -> true;
+safe_primop(bs_validate_unicode_retract) -> true;
+safe_primop(bs_put_small_float) -> true;
+safe_primop(bs_put_bits) -> true;
+safe_primop(emasculate_binary) -> true;
+safe_primop(atomic_inc) -> true;
+%% Not noproc but manually verified
+safe_primop(bs_put_big_integer) -> true;
+safe_primop(_) -> false.
diff --git a/lib/hipe/rtl/hipe_tagscheme.erl b/lib/hipe/rtl/hipe_tagscheme.erl
index 68cbe75e85..737f0ec5e3 100644
--- a/lib/hipe/rtl/hipe_tagscheme.erl
+++ b/lib/hipe/rtl/hipe_tagscheme.erl
@@ -53,7 +53,8 @@
 -export([test_subbinary/3, test_heap_binary/3]).
 -export([create_heap_binary/3, create_refc_binary/3, create_refc_binary/4]).
 -export([create_matchstate/6, convert_matchstate/1, compare_matchstate/4]).
--export([get_field_from_term/3, get_field_from_pointer/3,
+-export([get_field_addr_from_term/3,
+	 get_field_from_term/3, get_field_from_pointer/3,
 	 set_field_from_term/3, set_field_from_pointer/3,
 	 extract_matchbuffer/2, extract_binary_bytes/2]).
 
@@ -76,6 +77,10 @@
 -define(TAG_PRIMARY_BOXED,  16#2).
 -define(TAG_PRIMARY_IMMED1, 16#3).
 
+%% Only when ?ERTS_USE_LITERAL_TAG =:= 1
+-define(TAG_PTR_MASK__,   16#7).
+-define(TAG_LITERAL_PTR,  16#4).
+
 -define(TAG_IMMED1_SIZE,  4).
 -define(TAG_IMMED1_MASK,  16#F).
 -define(TAG_IMMED1_PID,   ((16#0 bsl ?TAG_PRIMARY_SIZE) bor ?TAG_PRIMARY_IMMED1)).
@@ -157,6 +162,38 @@ tag_cons(Res, X) ->
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
+ptr_val(Res, X) ->
+  hipe_rtl:mk_alu(Res, X, 'and', hipe_rtl:mk_imm(bnot ?TAG_PTR_MASK__)).
+
+%% Returns {Base, Offset, Untag}. To be used like, for example:
+%% {Base, Offset, Untag} = untag_ptr(X, ?TAG_PRIMARY_BOXED),
+%% ...
+%% [Untag, hipe_rtl:mk_load(Dst, Base, hipe_rtl:mk_imm(Offset))].
+%%
+%% NB: Base might either be X or a new temp. It must thus not be modified.
+untag_ptr(X, Tag) ->
+  case ?ERTS_USE_LITERAL_TAG of
+    0 ->
+      {X, -Tag, []};
+    1 ->
+      Base = hipe_rtl:mk_new_reg(),
+      Untag = ptr_val(Base, X),
+      {Base, 0, Untag}
+  end.
+
+untag_ptr_nooffset(Dst, X, Tag) ->
+  %% We could just use ptr_val in all cases, but subtraction can use LEA on x86
+  %% and can be inlined into effective address computations on several
+  %% architectures.
+  case ?ERTS_USE_LITERAL_TAG of
+    0 ->
+      hipe_rtl:mk_alu(Dst, X, 'sub', hipe_rtl:mk_imm(Tag));
+    1 ->
+      ptr_val(Dst, X)
+  end.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
 %%% Operations to test if an object has a known type T.
 
 test_nil(X, TrueLab, FalseLab, Pred) ->
@@ -171,7 +208,8 @@ test_is_boxed(X, TrueLab, FalseLab, Pred) ->
   hipe_rtl:mk_branch(X, 'and', Mask, 'eq', TrueLab, FalseLab, Pred).
 
 get_header(Res, X) ->
-  hipe_rtl:mk_load(Res, X, hipe_rtl:mk_imm(-(?TAG_PRIMARY_BOXED))).
+  {Base, Offset, Untag} = untag_ptr(X, ?TAG_PRIMARY_BOXED),
+  [Untag, hipe_rtl:mk_load(Res, Base, hipe_rtl:mk_imm(Offset))].
 
 mask_and_compare(X, Mask, Value, TrueLab, FalseLab, Pred) ->
   Tmp = hipe_rtl:mk_new_reg_gcsafe(),
@@ -617,21 +655,25 @@ test_either_immed(Arg1, Arg2, TrueLab, FalseLab) ->
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 unsafe_car(Dst, Arg) ->
-  hipe_rtl:mk_load(Dst, Arg, hipe_rtl:mk_imm(-(?TAG_PRIMARY_LIST))).
+  {Base, Offset, Untag} = untag_ptr(Arg, ?TAG_PRIMARY_LIST),
+  [Untag, hipe_rtl:mk_load(Dst, Base, hipe_rtl:mk_imm(Offset))].
 
 unsafe_cdr(Dst, Arg) ->
+  {Base, Offset, Untag} = untag_ptr(Arg, ?TAG_PRIMARY_LIST),
   WordSize = hipe_rtl_arch:word_size(),
-  hipe_rtl:mk_load(Dst, Arg, hipe_rtl:mk_imm(-(?TAG_PRIMARY_LIST)+WordSize)).
+  [Untag, hipe_rtl:mk_load(Dst, Base, hipe_rtl:mk_imm(Offset+WordSize))].
 
 unsafe_constant_element(Dst, Index, Tuple) ->	% Index is an immediate
   WordSize = hipe_rtl_arch:word_size(),
-  Offset = -(?TAG_PRIMARY_BOXED) + WordSize * hipe_rtl:imm_value(Index),
-  hipe_rtl:mk_load(Dst, Tuple, hipe_rtl:mk_imm(Offset)).
+  {Base, Offset0, Untag} = untag_ptr(Tuple, ?TAG_PRIMARY_BOXED),
+  Offset = Offset0 + WordSize * hipe_rtl:imm_value(Index),
+  [Untag, hipe_rtl:mk_load(Dst, Base, hipe_rtl:mk_imm(Offset))].
 
 unsafe_update_element(Tuple, Index, Value) ->   % Index is an immediate
   WordSize = hipe_rtl_arch:word_size(),
-  Offset = -(?TAG_PRIMARY_BOXED) + WordSize * hipe_rtl:imm_value(Index),
-  hipe_rtl:mk_store(Tuple, hipe_rtl:mk_imm(Offset), Value).
+  {Base, Offset0, Untag} = untag_ptr(Tuple, ?TAG_PRIMARY_BOXED),
+  Offset = Offset0 + WordSize * hipe_rtl:imm_value(Index),
+  [Untag, hipe_rtl:mk_store(Base, hipe_rtl:mk_imm(Offset), Value)].
 
 %%% wrong semantics
 %% unsafe_variable_element(Dst, Index, Tuple) -> % Index is an unknown fixnum
@@ -644,10 +686,12 @@ unsafe_update_element(Tuple, Index, Value) ->   % Index is an immediate
 %%     Tmp1 = hipe_rtl:mk_new_reg_gcsafe(),
 %%     Tmp2 = hipe_rtl:mk_new_reg_gcsafe(),
 %%     Shift = ?TAG_IMMED1_SIZE - 2,
-%%     OffAdj = (?TAG_IMMED1_SMALL bsr Shift) + ?TAG_PRIMARY_BOXED,
+%%     {Base, Off0, Untag} = untag_ptr(Tuple, ?TAG_PRIMARY_BOXED),
+%%     OffAdj = (?TAG_IMMED1_SMALL bsr Shift) - Off0,
 %%     [hipe_rtl:mk_alu(Tmp1, Index, 'srl', hipe_rtl:mk_imm(Shift)),
 %%      hipe_rtl:mk_alu(Tmp2, Tmp1, 'sub', hipe_rtl:mk_imm(OffAdj)),
-%%      hipe_rtl:mk_load(Dst, Tuple, Tmp2)].
+%%      Untag,
+%%      hipe_rtl:mk_load(Base, Tuple, Tmp2)].
 
 element(Dst, Index, Tuple, FailLabName, {tuple, A}, IndexInfo) ->
   FixnumOkLab = hipe_rtl:mk_new_label(),
@@ -660,7 +704,7 @@ element(Dst, Index, Tuple, FailLabName, {tuple, A}, IndexInfo) ->
       Offset = hipe_rtl:mk_new_reg_gcsafe(),
       Ptr = hipe_rtl:mk_new_reg(), % offset from Tuple
       [untag_fixnum(UIndex, Index),
-       hipe_rtl:mk_alu(Ptr, Tuple, 'sub', hipe_rtl:mk_imm(?TAG_PRIMARY_BOXED)),
+       untag_ptr_nooffset(Ptr, Tuple, ?TAG_PRIMARY_BOXED),
        hipe_rtl:mk_alu(Offset, UIndex, 'sll', 
 		       hipe_rtl:mk_imm(hipe_rtl_arch:log2_word_size())),
        hipe_rtl:mk_load(Dst, Ptr, Offset)];
@@ -769,7 +813,7 @@ gen_element_tail(Dst, Tuple, Arity, UIndex, FailLabName, IndexOkLab) ->
    hipe_rtl:mk_branch(ZeroIndex, 'geu', Arity, FailLabName,
 		      hipe_rtl:label_name(IndexOkLab), 0.01),
    IndexOkLab,
-   hipe_rtl:mk_alu(Ptr, Tuple, 'sub', hipe_rtl:mk_imm(?TAG_PRIMARY_BOXED)),
+   untag_ptr_nooffset(Ptr, Tuple, ?TAG_PRIMARY_BOXED),
    hipe_rtl:mk_alu(Offset, UIndex, 'sll',
                    hipe_rtl:mk_imm(hipe_rtl_arch:log2_word_size())),
    hipe_rtl:mk_load(Dst, Ptr, Offset)].
@@ -777,11 +821,13 @@ gen_element_tail(Dst, Tuple, Arity, UIndex, FailLabName, IndexOkLab) ->
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 unsafe_closure_element(Dst, Index, Closure) ->	% Index is an immediate
-  Offset = -(?TAG_PRIMARY_BOXED)    %% Untag
+  %% XXX: Can there even be closure literals?
+  {Base, Offset0, Untag} = untag_ptr(Closure, ?TAG_PRIMARY_BOXED),
+  Offset = Offset0                  %% Untag
     + ?EFT_ENV                      %% Field offset
                                     %% Index from 1 to N hence -1)
     + (hipe_rtl_arch:word_size() * (hipe_rtl:imm_value(Index)-1)),
-  hipe_rtl:mk_load(Dst, Closure, hipe_rtl:mk_imm(Offset)).
+  [Untag, hipe_rtl:mk_load(Dst, Base, hipe_rtl:mk_imm(Offset))].
 
 mk_fun_header() ->
   hipe_rtl:mk_imm(?HEADER_FUN).
@@ -790,7 +836,7 @@ tag_fun(Res, X) ->
   tag_boxed(Res, X).
 
 %% untag_fun(Res, X) ->
-%%   hipe_rtl:mk_alu(Res, X, 'sub', hipe_rtl:mk_imm(?TAG_PRIMARY_BOXED)).
+%%   untag_ptr_nooffset(Res, X, ?TAG_PRIMARY_BOXED).
 
 if_fun_get_arity_and_address(ArityReg, AddressReg, FunP, BadFunLab, Pred) ->
   %% EmuAddressPtrReg = hipe_rtl:mk_new_reg(),
@@ -801,15 +847,15 @@ if_fun_get_arity_and_address(ArityReg, AddressReg, FunP, BadFunLab, Pred) ->
   TrueLab0 = hipe_rtl:mk_new_label(),
   %% TrueLab1 = hipe_rtl:mk_new_label(),
   IsFunCode = test_closure(FunP, hipe_rtl:label_name(TrueLab0), BadFunLab, Pred),
+  {Base, Offset, Untag} = untag_ptr(FunP, ?TAG_PRIMARY_BOXED),
   GetArityCode =
     [TrueLab0,
      %% Funp->arity contains the arity
-     hipe_rtl:mk_load(ArityReg, FunP,
-		      hipe_rtl:mk_imm(-(?TAG_PRIMARY_BOXED)+
-				      ?EFT_ARITY)),
-     hipe_rtl:mk_load(FEPtrReg, FunP,
-		      hipe_rtl:mk_imm(-(?TAG_PRIMARY_BOXED)+
-				      ?EFT_FE)),
+     Untag,
+     hipe_rtl:mk_load(ArityReg, Base,
+		      hipe_rtl:mk_imm(Offset+?EFT_ARITY)),
+     hipe_rtl:mk_load(FEPtrReg, Base,
+		      hipe_rtl:mk_imm(Offset+?EFT_FE)),
      hipe_rtl:mk_load(AddressReg, FEPtrReg,
 		      hipe_rtl:mk_imm(?EFE_NATIVE_ADDRESS))],
   IsFunCode ++ GetArityCode.
@@ -927,20 +973,24 @@ test_subbinary(Binary, TrueLblName, FalseLblName) ->
 
 unsafe_load_float(DstLo, DstHi, Src) ->
   WordSize = hipe_rtl_arch:word_size(),
-  Offset1 = -(?TAG_PRIMARY_BOXED) + WordSize,
+  {Base, Offset0, Untag} = untag_ptr(Src, ?TAG_PRIMARY_BOXED),
+  Offset1 = Offset0 + WordSize,
   Offset2 = Offset1 + 4, %% This should really be 4 and not WordSize
   case hipe_rtl_arch:endianess() of
     little ->
-      [hipe_rtl:mk_load(DstLo, Src, hipe_rtl:mk_imm(Offset1), int32, unsigned),
-       hipe_rtl:mk_load(DstHi, Src, hipe_rtl:mk_imm(Offset2), int32, unsigned)];
+      [Untag,
+       hipe_rtl:mk_load(DstLo, Base, hipe_rtl:mk_imm(Offset1), int32, unsigned),
+       hipe_rtl:mk_load(DstHi, Base, hipe_rtl:mk_imm(Offset2), int32, unsigned)];
     big ->
-      [hipe_rtl:mk_load(DstHi, Src, hipe_rtl:mk_imm(Offset1), int32, unsigned),
-       hipe_rtl:mk_load(DstLo, Src, hipe_rtl:mk_imm(Offset2), int32, unsigned)]
+      [Untag,
+       hipe_rtl:mk_load(DstHi, Base, hipe_rtl:mk_imm(Offset1), int32, unsigned),
+       hipe_rtl:mk_load(DstLo, Base, hipe_rtl:mk_imm(Offset2), int32, unsigned)]
   end. 
 
 unsafe_untag_float(Dst, Src) ->
-  Offset = -(?TAG_PRIMARY_BOXED) + hipe_rtl_arch:word_size(),
-  [hipe_rtl:mk_fload(Dst, Src, hipe_rtl:mk_imm(Offset))].
+  {Base, Offset0, Untag} = untag_ptr(Src, ?TAG_PRIMARY_BOXED),
+  Offset = Offset0 + hipe_rtl_arch:word_size(),
+  [Untag, hipe_rtl:mk_fload(Dst, Base, hipe_rtl:mk_imm(Offset))].
 
 unsafe_tag_float(Dst, Src) ->
   {GetHPInsn, HP, PutHPInsn} = hipe_rtl_arch:heap_pointer(),
@@ -999,8 +1049,9 @@ get_one_word_pos_bignum(USize, Size, Fail) ->
 
 unsafe_get_one_word_pos_bignum(USize, Size) ->
   WordSize = hipe_rtl_arch:word_size(),
-  Imm = hipe_rtl:mk_imm(1*WordSize-?TAG_PRIMARY_BOXED),
-  [hipe_rtl:mk_load(USize, Size, Imm)].
+  {Base, Offset, Untag} = untag_ptr(Size, ?TAG_PRIMARY_BOXED),
+  Imm = hipe_rtl:mk_imm(1*WordSize+Offset),
+  [Untag, hipe_rtl:mk_load(USize, Base, Imm)].
 
 -spec bignum_sizeneed(non_neg_integer()) -> non_neg_integer().
 
@@ -1040,7 +1091,7 @@ create_matchstate(Max, BinSize, Base, Offset, Orig, Ms) ->
   SizeInWords = ((ByteSize div WordSize) - 1),
   Header = hipe_rtl:mk_imm(mk_header(SizeInWords, ?TAG_HEADER_BIN_MATCHSTATE)),
   [GetHPInsn,
-   hipe_rtl:mk_alu(Ms, HP, add, hipe_rtl:mk_imm(?TAG_PRIMARY_BOXED)),
+   tag_boxed(Ms, HP),
    set_field_from_term({matchstate,thing_word}, Ms, Header),
    set_field_from_term({matchstate,{matchbuffer,orig}}, Ms, Orig),
    set_field_from_term({matchstate,{matchbuffer,base}}, Ms, Base),
@@ -1078,7 +1129,10 @@ convert_matchstate(Ms) ->
    size_from_header(SizeInWords, Header),
    hipe_rtl:mk_alu(Hole, SizeInWords, sub, hipe_rtl:mk_imm(?SUB_BIN_WORDSIZE)),
    mk_var_header(BigIntHeader, Hole, ?TAG_HEADER_POS_BIG),
-   hipe_rtl:mk_store(Ms, hipe_rtl:mk_imm(?SUB_BIN_WORDSIZE*WordSize-?TAG_PRIMARY_BOXED),
+   %% Matchstates can't be literals; so untagging with ?TAG_PRIMARY_BOXED is
+   %% fine here
+   hipe_rtl:mk_store(Ms, hipe_rtl:mk_imm(?SUB_BIN_WORDSIZE*WordSize
+                                         -?TAG_PRIMARY_BOXED),
 		     BigIntHeader)].
 
 compare_matchstate(Max, Ms, LargeEnough, TooSmall) ->
@@ -1087,8 +1141,10 @@ compare_matchstate(Max, Ms, LargeEnough, TooSmall) ->
   SizeInWords = ((ByteSize div WordSize) - 1),
   Header = hipe_rtl:mk_imm(mk_header(SizeInWords, ?TAG_HEADER_BIN_MATCHSTATE)),
   RealHeader = hipe_rtl:mk_new_reg_gcsafe(),
-   [hipe_rtl:mk_load(RealHeader, Ms, hipe_rtl:mk_imm(-?TAG_PRIMARY_BOXED)),
-    hipe_rtl:mk_branch(RealHeader, ge, Header, LargeEnough, TooSmall)].
+  %% Matchstates can't be literals; so untagging with ?TAG_PRIMARY_BOXED is fine
+  %% here
+  [hipe_rtl:mk_load(RealHeader, Ms, hipe_rtl:mk_imm(-?TAG_PRIMARY_BOXED)),
+   hipe_rtl:mk_branch(RealHeader, ge, Header, LargeEnough, TooSmall)].
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%
@@ -1207,15 +1263,22 @@ get_field_size1({matchbuffer, base}) ->
 get_field_size1({matchbuffer, binsize}) ->  
   ?MB_SIZE_SIZE.
 
+get_field_addr_from_term(Struct, Term, Dst) ->
+  {Base, Offset0, Untag} = untag_ptr(Term, ?TAG_PRIMARY_BOXED),
+  Offset = hipe_rtl:mk_imm(get_field_offset(Struct) + Offset0),
+  [Untag, hipe_rtl:mk_alu(Dst, Base, add, Offset)].
+
 get_field_from_term(Struct, Term, Dst) ->
-  Offset = hipe_rtl:mk_imm(get_field_offset(Struct) - ?TAG_PRIMARY_BOXED),
+  {Base, Offset0, Untag} = untag_ptr(Term, ?TAG_PRIMARY_BOXED),
+  Offset = hipe_rtl:mk_imm(get_field_offset(Struct) + Offset0),
   Size = get_field_size(Struct),
-  hipe_rtl:mk_load(Dst, Term, Offset, Size, unsigned). 
+  [Untag, hipe_rtl:mk_load(Dst, Base, Offset, Size, unsigned)].
 
 set_field_from_term(Struct, Term, Value) ->
-  Offset = hipe_rtl:mk_imm(get_field_offset(Struct) - ?TAG_PRIMARY_BOXED),
+  {Base, Offset0, Untag} = untag_ptr(Term, ?TAG_PRIMARY_BOXED),
+  Offset = hipe_rtl:mk_imm(get_field_offset(Struct) + Offset0),
   Size = get_field_size(Struct),
-  hipe_rtl:mk_store(Term, Offset, Value, Size).
+  [Untag, hipe_rtl:mk_store(Base, Offset, Value, Size)].
 
 get_field_from_pointer(Struct, Term, Dst) ->
   Offset = hipe_rtl:mk_imm(get_field_offset(Struct)),
@@ -1229,6 +1292,8 @@ set_field_from_pointer(Struct, Term, Value) ->
   
 extract_matchbuffer(Mb, Ms) ->
   What = {matchstate, matchbuffer},
+  %% Matchstates can't be literals; so untagging with ?TAG_PRIMARY_BOXED is fine
+  %% here
   Offset = hipe_rtl:mk_imm(get_field_offset(What) - ?TAG_PRIMARY_BOXED),
   hipe_rtl:mk_alu(Mb, Ms, add, Offset).
 
diff --git a/lib/hipe/ssa/hipe_ssa.inc b/lib/hipe/ssa/hipe_ssa.inc
index c7c1a8e1d7..29e8b92266 100644
--- a/lib/hipe/ssa/hipe_ssa.inc
+++ b/lib/hipe/ssa/hipe_ssa.inc
@@ -463,20 +463,20 @@ updateStatementDefs([], Statement, Current, Acc) ->
 %%----------------------------------------------------------------------
 
 updateIndices(Current, Variable) ->
-  case ?CODE:is_var(Variable) of
-    true ->
-      NewVar = ?CODE:mk_new_var(),
-      {NewVar,gb_trees:enter(Variable, NewVar, Current)};
-    false ->
-      case is_fp_temp(Variable) of
-	true ->
-	  NewFVar = mk_new_fp_temp(),
-	  {NewFVar,gb_trees:enter(Variable, NewFVar, Current)};
-	false ->
-	  NewReg = ?CODE:mk_new_reg(),
-	  {NewReg,gb_trees:enter(Variable, NewReg, Current)}
-      end
-  end.
+  New =
+    case ?CODE:is_var(Variable) of
+      true -> ?CODE:mk_new_var();
+      false ->
+        case is_fp_temp(Variable) of
+          true -> mk_new_fp_temp();
+          false ->
+            case ?CODE:reg_is_gcsafe(Variable) of
+              true -> ?CODE:mk_new_reg_gcsafe();
+              false -> ?CODE:mk_new_reg()
+            end
+        end
+    end,
+  {New, gb_trees:enter(Variable, New, Current)}.
 
 %%----------------------------------------------------------------------
 %% Procedure : updateSuccPhi/4
diff --git a/lib/hipe/test/basic_SUITE_data/basic_exceptions.erl b/lib/hipe/test/basic_SUITE_data/basic_exceptions.erl
index 229a0516dc..d71b924d22 100644
--- a/lib/hipe/test/basic_SUITE_data/basic_exceptions.erl
+++ b/lib/hipe/test/basic_SUITE_data/basic_exceptions.erl
@@ -6,12 +6,13 @@
 %%%-------------------------------------------------------------------
 -module(basic_exceptions).
 
--export([test/0, test_catches/0]).
+-export([test/0]).
 
 %% functions used as arguments to spawn/3
 -export([bad_guy/2]).
 
 test() ->
+  ok = test_catches(),
   ok = test_catch_exit(42),
   ok = test_catch_throw(42),
   ok = test_catch_element(),
@@ -22,6 +23,7 @@ test() ->
   ok = test_pending_errors(),
   ok = test_bad_fun_call(),
   ok = test_guard_bif(),
+  ok = test_eclectic(),
   ok.
 
 %%--------------------------------------------------------------------
@@ -463,3 +465,117 @@ guard_bif('node/0', X, Y) when node() == Y ->
   {'node/0', X, Y};
 guard_bif('node/1', X, Y) when node(X) == Y ->
   {'node/1', X, Y}.
+
+%%--------------------------------------------------------------------
+%% Taken from trycatch_SUITE.erl (compiler test suite).
+%%
+%% Cases that are commented out contain exception information that was
+%% added to Erlang/OTP in commit e8d45ae14c6c3bdfcbbc7964228b004ef4f11ea6
+%% (May 2017) only in the BEAM emulator.  Thus, part of this test fails
+%% when compiled in native code.
+%% The remaining cases are uncommented so that they are properly tested
+%% in native code too.
+%%--------------------------------------------------------------------
+
+test_eclectic() ->
+  V = {make_ref(),3.1415926535,[[]|{}]},
+  {{value,{value,V},V},V} =
+    eclectic_1({foo,{value,{value,V}}}, undefined, {value,V}),
+  {{'EXIT',{V,[{?MODULE,foo,1,_}|_]}},V} =
+    eclectic_1({catch_foo,{error,V}}, undefined, {value,V}),
+  {{error,{exit,V},{'EXIT',V}},V} =
+    eclectic_1({foo,{error,{exit,V}}}, error, {value,V}),
+  %% {{value,{value,V},V},
+  %%        {'EXIT',{badarith,[{erlang,'+',[0,a],_},{?MODULE,my_add,2,_}|_]}}} =
+  %%     eclectic_1({foo,{value,{value,V}}}, undefined, {'add',{0,a}}),
+  {{'EXIT',V},V} =
+    eclectic_1({catch_foo,{exit,V}}, undefined, {throw,V}),
+  %% {{error,{'div',{1,0}},{'EXIT',{badarith,[{erlang,'div',[1,0],_},{?MODULE,my_div,2,_}|_]}}},
+  %%        {'EXIT',V}} =
+  %%     eclectic_1({foo,{error,{'div',{1,0}}}}, error, {exit,V}),
+  {{{error,V},{'EXIT',{V,[{?MODULE,foo,1,_}|_]}}},
+   {'EXIT',V}} =
+    eclectic_1({catch_foo,{throw,{error,V}}}, undefined, {exit,V}),
+  %%
+  {{value,{value,{value,V},V}},V} =
+    eclectic_2({value,{value,V}}, undefined, {value,V}),
+  {{value,{throw,{value,V},V}},V} =
+    eclectic_2({throw,{value,V}}, throw, {value,V}),
+  {{caught,{'EXIT',V}},undefined} =
+    eclectic_2({value,{value,V}}, undefined, {exit,V}),
+  {{caught,{'EXIT',{V,[{?MODULE,foo,1,_}|_]}}},undefined} =
+    eclectic_2({error,{value,V}}, throw, {error,V}),
+  %% The following fails in native code
+  %% %% {{caught,{'EXIT',{badarg,[{erlang,abs,[V],_}|_]}}},V} =
+  %% %%     eclectic_2({value,{'abs',V}}, undefined, {value,V}),
+  %% {{caught,{'EXIT',{badarith,[{erlang,'+',[0,a],_},{?MODULE,my_add,2,_}|_]}}},V} =
+  %%     eclectic_2({exit,{'add',{0,a}}}, exit, {value,V}),
+  {{caught,{'EXIT',V}},undefined} =
+    eclectic_2({value,{error,V}}, undefined, {exit,V}),
+  {{caught,{'EXIT',{V,[{?MODULE,foo,1,_}|_]}}},undefined} =
+    eclectic_2({throw,{'div',{1,0}}}, throw, {error,V}),
+  ok.
+
+eclectic_1(X, C, Y) ->
+  erase(eclectic),
+  Done = make_ref(),
+  Try =
+    try case X of
+          {catch_foo,V} -> catch {Done,foo(V)};
+          {foo,V} -> {Done,foo(V)}
+        end of
+        {Done,D} -> {value,D,catch foo(D)};
+        {'EXIT',_}=Exit -> Exit;
+        D -> {D,catch foo(D)}
+    catch
+      C:D -> {C,D,catch foo(D)}
+    after
+      put(eclectic, catch foo(Y))
+    end,
+  {Try,erase(eclectic)}.
+
+eclectic_2(X, C, Y) ->
+  Done = make_ref(),
+  erase(eclectic),
+  Catch =
+    case
+      catch
+        {Done,
+         try foo(X) of
+             V -> {value,V,foo(V)}
+         catch
+           C:D -> {C,D,foo(D)}
+         after
+           put(eclectic, foo(Y))
+         end} of
+        {Done,Z} -> {value,Z};
+        Z -> {caught,Z}
+      end,
+  {Catch,erase(eclectic)}.
+
+foo({value,Value}) -> Value;
+foo({'div',{A,B}}) ->
+  my_div(A, B);
+foo({'add',{A,B}}) ->
+  my_add(A, B);
+foo({'abs',X}) ->
+  my_abs(X);
+foo({error,Error}) ->
+  erlang:error(Error);
+foo({throw,Throw}) ->
+  erlang:throw(Throw);
+foo({exit,Exit}) ->
+  erlang:exit(Exit);
+foo({raise,{Class,Reason}}) ->
+  erlang:raise(Class, Reason);
+foo(Term) when not is_atom(Term) -> Term.
+%%foo(Atom) when is_atom(Atom) -> % must not be defined!
+
+my_div(A, B) ->
+  A div B.
+
+my_add(A, B) ->
+  A + B.
+
+my_abs(X) ->
+  abs(X).
diff --git a/lib/hipe/test/basic_SUITE_data/basic_receive.erl b/lib/hipe/test/basic_SUITE_data/basic_receive.erl
index 5f865d7b7a..20e3f350e8 100644
--- a/lib/hipe/test/basic_SUITE_data/basic_receive.erl
+++ b/lib/hipe/test/basic_SUITE_data/basic_receive.erl
@@ -12,6 +12,7 @@ test() ->
   ok = test_wait_timeout(),
   ok = test_double_timeout(),
   ok = test_reschedule(),
+  ok = test_recv_mark(),
   ok.
 
 %%--------------------------------------------------------------------
@@ -54,3 +55,91 @@ doit(First) ->
   erts_debug:set_internal_state(hipe_test_reschedule_suspend, 1).
 
 %%--------------------------------------------------------------------
+%% Check that we cannot cause a recv_mark,recv_set pair to misbehave and
+%% deadlock the process.
+
+test_recv_mark() ->
+  ok = test_recv_mark(fun disturber_nop/0),
+  ok = test_recv_mark(fun disturber_receive/0),
+  ok = test_recv_mark(fun disturber_other/0),
+  ok = test_recv_mark(fun disturber_recurse/0),
+  ok = test_recv_mark_after(self(), fun disturber_after_recurse/0, false),
+  ok = test_recv_mark(fun disturber_other_recurse/0),
+  ok = test_recv_mark(fun disturber_other_after/0),
+  ok = test_recv_mark_nested().
+
+test_recv_mark(Disturber) ->
+  Ref = make_ref(),
+  self() ! Ref,
+  Disturber(),
+  receive Ref -> ok
+  after 0 -> error(failure)
+  end.
+
+disturber_nop() -> ok.
+
+disturber_receive() ->
+  self() ! message,
+  receive message -> ok end.
+
+disturber_other() ->
+  Ref = make_ref(),
+  self() ! Ref,
+  receive Ref -> ok end.
+
+disturber_recurse() ->
+  aborted = (catch test_recv_mark(fun() -> throw(aborted) end)),
+  ok.
+
+test_recv_mark_after(Recipient, Disturber, IsInner) ->
+  Ref = make_ref(),
+  Recipient ! Ref,
+  Disturber(),
+  receive
+      Ref -> ok
+  after 0 ->
+          case IsInner of
+              true -> expected;
+              false -> error(failure)
+          end
+  end.
+
+disturber_after_recurse() ->
+  NoOp = fun() -> ok end,
+  BlackHole = spawn(NoOp),
+  expected = test_recv_mark_after(BlackHole, NoOp, true),
+  ok.
+
+disturber_other_recurse() ->
+  aborted = (catch disturber_other_recurse(fun() -> throw(aborted) end)),
+  ok.
+
+disturber_other_recurse(InnerD) ->
+  Ref = make_ref(),
+  self() ! Ref,
+  InnerD(),
+  receive Ref -> ok
+  after 0 -> error(failure)
+  end.
+
+disturber_other_after() ->
+  BlackHole = spawn(fun() -> ok end),
+  Ref = make_ref(),
+  BlackHole ! Ref,
+  receive Ref -> error(imposible)
+  after 0 -> ok
+  end.
+
+test_recv_mark_nested() ->
+  Ref1 = make_ref(),
+  self() ! Ref1,
+  begin
+    Ref2 = make_ref(),
+    self() ! Ref2,
+    receive Ref2 -> ok end
+  end,
+  receive Ref1 -> ok
+  after 0 -> error(failure)
+  end.
+
+%%--------------------------------------------------------------------
diff --git a/lib/hipe/test/hipe_testsuite_driver.erl b/lib/hipe/test/hipe_testsuite_driver.erl
index 88576775ca..8813af5dfc 100644
--- a/lib/hipe/test/hipe_testsuite_driver.erl
+++ b/lib/hipe/test/hipe_testsuite_driver.erl
@@ -29,13 +29,9 @@ get_suites(SuitesWithSuiteSuffix) ->
     [S || {yes, S} <- Prefixes].
 
 suffix(String, Suffix) ->
-    case string:rstr(String, Suffix) of
-	0 -> no;
-	Index ->
-	    case string:substr(String, Index) =:= Suffix of
-		true -> {yes, string:sub_string(String, 1, Index-1)};
-		false -> no
-	    end
+    case string:split(String, Suffix, trailing) of
+	[Prefix,[]] -> {yes, Prefix};
+        _ -> no
     end.
 
 -spec file_type(file:filename()) -> {ok, file_type()} | {error, ext_posix()}.
@@ -165,7 +161,8 @@ run(TestCase, Dir, _OutDir) ->
     %% 		  end, DataFiles),
     %% try
     ok = TestCase:test(),
-    HiPEOpts = try TestCase:hipe_options() catch error:undef -> [] end,
+    HiPEOpts0 = try TestCase:hipe_options() catch error:undef -> [] end,
+    HiPEOpts = HiPEOpts0 ++ hipe_options(),
     {ok, TestCase} = hipe:c(TestCase, HiPEOpts),
     ok = TestCase:test(),
     {ok, TestCase} = hipe:c(TestCase, [o1|HiPEOpts]),
@@ -183,3 +180,6 @@ run(TestCase, Dir, _OutDir) ->
     %% 	lists:foreach(fun (DF) -> ok end, % = file:delete(DF) end,
     %% 		      [filename:join(OutDir, D) || D <- DataFiles])
     %% end.
+
+hipe_options() ->
+    [verify_gcsafe].
diff --git a/lib/hipe/test/opt_verify_SUITE.erl b/lib/hipe/test/opt_verify_SUITE.erl
index a323c10503..24f43af275 100644
--- a/lib/hipe/test/opt_verify_SUITE.erl
+++ b/lib/hipe/test/opt_verify_SUITE.erl
@@ -59,7 +59,7 @@ call_elim_test_file(Config, FileName, Option) ->
 substring_count(Icode, Substring) ->
     substring_count(Icode, Substring, 0).
 substring_count(Icode, Substring, N) ->
-    case string:str(Icode, Substring) of
-        0 -> N;
-        I -> substring_count(lists:nthtail(I, Icode), Substring, N+1)
+    case string:find(Icode, Substring) of
+        nomatch -> N;
+        Prefix -> substring_count(string:prefix(Prefix, Substring), Substring, N+1)
     end.
diff --git a/lib/inets/doc/src/httpc.xml b/lib/inets/doc/src/httpc.xml
index 29e4b22632..58714328c5 100644
--- a/lib/inets/doc/src/httpc.xml
+++ b/lib/inets/doc/src/httpc.xml
@@ -287,8 +287,7 @@
                            {autoredirect,    boolean()} | 
                            {proxy_auth, {userstring(), passwordstring()}} | 
                            {version,         http_version()} | 
-                           {relaxed,         boolean()} |
-	                   {url_encode,      boolean()}</v>
+                           {relaxed,         boolean()}</v>
         <v>timeout() = integer() >= 0 | infinity</v>
         <v>Options = options()</v>
         <v>options() = [option()]</v>
@@ -379,13 +378,6 @@
 	    from the HTTP-standard are enabled.</p>
             <p>Default is <c>false</c>.</p>
 	  </item>
-
-	  <tag><c><![CDATA[url_encode]]></c></tag>
-          <item>
-            <p>Applies Percent-encoding, also known as URL encoding on the 
-	    URL.</p>
-	    <p>Default is <c>false</c>.</p>
-	  </item>
         </taglist>
 
         <p>Option (<c>option()</c>) details:</p>
diff --git a/lib/inets/src/http_client/httpc.erl b/lib/inets/src/http_client/httpc.erl
index bf2da82603..821eb7f02f 100644
--- a/lib/inets/src/http_client/httpc.erl
+++ b/lib/inets/src/http_client/httpc.erl
@@ -175,10 +175,10 @@ request(Method,
        (Method =:= delete) orelse 
        (Method =:= trace) andalso 
        (is_atom(Profile) orelse is_pid(Profile)) ->
-    case uri_parse(Url, Options) of
-	{error, Reason} ->
+    case uri_string:parse(uri_string:normalize(Url)) of
+	{error, Reason, _} ->
 	    {error, Reason};
-	{ok, ParsedUrl} ->
+	ParsedUrl ->
 	    case header_parse(Headers) of
 		{error, Reason} ->
 		    {error, Reason};
@@ -189,10 +189,10 @@ request(Method,
     end.
 
 do_request(Method, {Url, Headers, ContentType, Body}, HTTPOptions, Options, Profile) ->
-    case uri_parse(Url, Options) of
-	{error, Reason} ->
+    case uri_string:parse(uri_string:normalize(Url)) of
+	{error, Reason, _} ->
 	    {error, Reason};
-	{ok, ParsedUrl} ->
+	ParsedUrl ->
 	    handle_request(Method, Url, 
 			   ParsedUrl, Headers, ContentType, Body, 
 			   HTTPOptions, Options, Profile)
@@ -312,23 +312,28 @@ store_cookies(SetCookieHeaders, Url) ->
 
 store_cookies(SetCookieHeaders, Url, Profile) 
   when is_atom(Profile) orelse is_pid(Profile) ->
-    try 
-	begin
+    case uri_string:parse(uri_string:normalize(Url)) of
+        {error, Bad, _} ->
+            {error, {parse_failed, Bad}};
+        URI ->
+            Scheme = scheme_to_atom(maps:get(scheme, URI, '')),
+            Host = maps:get(host, URI, ""),
+            Port = maps:get(port, URI, default_port(Scheme)),
+            Path = uri_string:recompose(#{path => maps:get(path, URI, "")}),
 	    %% Since the Address part is not actually used
 	    %% by the manager when storing cookies, we dont
 	    %% care about ipv6-host-with-brackets.
-	    {ok, {_, _, Host, Port, Path, _}} = uri_parse(Url),
 	    Address     = {Host, Port}, 
 	    ProfileName = profile_name(Profile),
 	    Cookies     = httpc_cookie:cookies(SetCookieHeaders, Path, Host),
 	    httpc_manager:store_cookies(Cookies, Address, ProfileName), 
 	    ok
-	end
-    catch 
-	error:{badmatch, Bad} ->
-	    {error, {parse_failed, Bad}}
     end.
 
+default_port(http) ->
+    80;
+default_port(https) ->
+    443.
 
 %%--------------------------------------------------------------------------
 %% cookie_header(Url) -> Header | {error, Reason}
@@ -495,7 +500,7 @@ service_info(Pid) ->
 %%% Internal functions
 %%%========================================================================
 handle_request(Method, Url, 
-	       {Scheme, UserInfo, Host, Port, Path, Query}, 
+               URI,
 	       Headers0, ContentType, Body0,
 	       HTTPOptions0, Options0, Profile) ->
 
@@ -520,37 +525,40 @@ handle_request(Method, Url,
 			throw({error, {bad_body, Body0}})
 		end,
 
-	    HTTPOptions   = http_options(HTTPOptions0),
-	    Options       = request_options(Options0), 
-	    Sync          = proplists:get_value(sync,   Options),
-	    Stream        = proplists:get_value(stream, Options),
-	    Host2         = http_request:normalize_host(Scheme, Host, Port),
-	    HeadersRecord = header_record(NewHeaders, Host2, HTTPOptions),
-	    Receiver      = proplists:get_value(receiver, Options),
-	    SocketOpts    = proplists:get_value(socket_opts, Options),
-	    BracketedHost = proplists:get_value(ipv6_host_with_brackets, 
-						Options),
-	    MaybeEscPath  = maybe_encode_uri(HTTPOptions, Path),
-	    MaybeEscQuery = maybe_encode_uri(HTTPOptions, Query),
-	    AbsUri        = maybe_encode_uri(HTTPOptions, Url),
+            HTTPOptions   = http_options(HTTPOptions0),
+            Options       = request_options(Options0),
+            Sync          = proplists:get_value(sync,   Options),
+            Stream        = proplists:get_value(stream, Options),
+            Receiver      = proplists:get_value(receiver, Options),
+            SocketOpts    = proplists:get_value(socket_opts, Options),
+            BracketedHost = proplists:get_value(ipv6_host_with_brackets,
+                                                Options),
+
+            Scheme        = scheme_to_atom(maps:get(scheme, URI, '')),
+            Userinfo      = maps:get(userinfo, URI, ""),
+            Host          = http_util:maybe_add_brackets(maps:get(host, URI, ""), BracketedHost),
+            Port          = maps:get(port, URI, default_port(Scheme)),
+            Host2         = http_request:normalize_host(Scheme, Host, Port),
+            Path          = uri_string:recompose(#{path => maps:get(path, URI, "")}),
+            Query         = add_question_mark(maps:get(query, URI, "")),
+            HeadersRecord = header_record(NewHeaders, Host2, HTTPOptions),
 
 	    Request = #request{from          = Receiver,
-			       scheme        = Scheme, 
-			       address       = {host_address(Host, BracketedHost), Port},
-			       path          = MaybeEscPath,
-			       pquery        = MaybeEscQuery,
+			       scheme        = Scheme,
+			       address       = {Host, Port},
+			       path          = Path,
+			       pquery        = Query,
 			       method        = Method,
 			       headers       = HeadersRecord, 
 			       content       = {ContentType, Body},
 			       settings      = HTTPOptions, 
-			       abs_uri       = AbsUri,
-			       userinfo      = UserInfo, 
+			       abs_uri       = Url,
+			       userinfo      = Userinfo,
 			       stream        = Stream, 
 			       headers_as_is = headers_as_is(Headers0, Options),
 			       socket_opts   = SocketOpts, 
 			       started       = Started,
 			       ipv6_host_with_brackets = BracketedHost},
-
 	    case httpc_manager:request(Request, profile_name(Profile)) of
 		{ok, RequestId} ->
 		    handle_answer(RequestId, Sync, Options);
@@ -565,14 +573,31 @@ handle_request(Method, Url,
 	    Error
     end.
 
+
+add_question_mark(<<>>) ->
+    <<>>;
+add_question_mark([]) ->
+    [];
+add_question_mark(Comp) when is_binary(Comp) ->
+    <<$?, Comp/binary>>;
+add_question_mark(Comp) when is_list(Comp) ->
+    [$?|Comp].
+
+
+scheme_to_atom("http") ->
+    http;
+scheme_to_atom("https") ->
+    https;
+scheme_to_atom('') ->
+    '';
+scheme_to_atom(Scheme) ->
+    throw({error, {bad_scheme, Scheme}}).
+
+
 ensure_chunked_encoding(Hdrs) ->
     Key = "transfer-encoding",
     lists:keystore(Key, 1, Hdrs, {Key, "chunked"}).
 
-maybe_encode_uri(#http_options{url_encode = true}, URI) ->
-    http_uri:encode(URI);
-maybe_encode_uri(_, URI) ->
-    URI.
 
 mk_chunkify_fun(ProcessBody) ->
     fun(eof_body) ->
@@ -1190,17 +1215,6 @@ validate_headers(RequestHeaders, _, _) ->
 %% These functions is just simple wrappers to parse specifically HTTP URIs
 %%--------------------------------------------------------------------------
 
-scheme_defaults() ->
-    [{http, 80}, {https, 443}].
-
-uri_parse(URI) ->
-    http_uri:parse(URI, [{scheme_defaults, scheme_defaults()}]).
-
-uri_parse(URI, Opts) ->
-    http_uri:parse(URI, [{scheme_defaults, scheme_defaults()} | Opts]).
-
-
-%%--------------------------------------------------------------------------
 header_parse([]) ->
     ok;
 header_parse([{Field, Value}|T]) when is_list(Field), is_list(Value) ->    
@@ -1221,10 +1235,6 @@ child_name(Pid, [{Name, Pid} | _]) ->
 child_name(Pid, [_ | Children]) ->
     child_name(Pid, Children).
 
-host_address(Host, false) ->
-    Host;
-host_address(Host, true) ->
-    string:strip(string:strip(Host, right, $]), left, $[).
 
 check_body_gen({Fun, _}) when is_function(Fun) -> 
     ok;
diff --git a/lib/inets/src/http_client/httpc_response.erl b/lib/inets/src/http_client/httpc_response.erl
index 91638f5d2e..58ab9144df 100644
--- a/lib/inets/src/http_client/httpc_response.erl
+++ b/lib/inets/src/http_client/httpc_response.erl
@@ -190,7 +190,7 @@ parse_status_code(<<?CR, ?LF, Rest/binary>>, StatusCodeStr,
 		  MaxHeaderSize, Result, true) ->
     parse_headers(Rest, [], [], MaxHeaderSize,
  		  [" ", list_to_integer(lists:reverse(
-				     string:strip(StatusCodeStr))) 
+                                          string:trim(StatusCodeStr)))
 		   | Result], true); 
 
 parse_status_code(<<?SP, Rest/binary>>, StatusCodeStr, 
@@ -377,58 +377,173 @@ status_server_error_50x(Response, Request) ->
     {stop, {Request#request.id, Msg}}.
 
 
-redirect(Response = {StatusLine, Headers, Body}, Request) ->
+redirect(Response = {_, Headers, _}, Request) ->
     {_, Data} =  format_response(Response),
     case Headers#http_response_h.location of
-	undefined ->
-	    transparent(Response, Request);
-	RedirUrl ->
-	    UrlParseOpts = [{ipv6_host_with_brackets, 
-			     Request#request.ipv6_host_with_brackets}], 
-	    case uri_parse(RedirUrl, UrlParseOpts) of
-		{error, no_scheme} when
-		(Request#request.settings)#http_options.relaxed ->
-		    NewLocation = fix_relative_uri(Request, RedirUrl),
-		    redirect({StatusLine, Headers#http_response_h{
-					    location = NewLocation},
-			      Body}, Request);
-		{error, Reason} ->
-		    {ok, error(Request, Reason), Data};
-		%% Automatic redirection
-		{ok, {Scheme, _, Host, Port, Path,  Query}} -> 
-		    HostPort = http_request:normalize_host(Scheme, Host, Port),
-		    NewHeaders = 
-			(Request#request.headers)#http_request_h{host = HostPort},
-		    NewRequest = 
-			Request#request{redircount = 
-					Request#request.redircount+1,
-					scheme = Scheme,
-					headers = NewHeaders,
-					address = {Host,Port},
-					path = Path,
-					pquery = Query,
-					abs_uri =
-					atom_to_list(Scheme) ++ "://" ++
-                                        Host ++ ":" ++ 
-					integer_to_list(Port) ++
-					Path ++ Query},
-		    {redirect, NewRequest, Data}
-	    end
+        undefined ->
+            transparent(Response, Request);
+        RedirUrl ->
+            Brackets = Request#request.ipv6_host_with_brackets,
+            case uri_string:parse(RedirUrl) of
+                {error, Reason, _} ->
+                    {ok, error(Request, Reason), Data};
+                %% Automatic redirection
+                URI ->
+                    {Host, Port0} = Request#request.address,
+                    Port = maybe_to_integer(Port0),
+                    Path = Request#request.path,
+                    Scheme = atom_to_list(Request#request.scheme),
+                    Query = Request#request.pquery,
+                    URIMap = resolve_uri(Scheme, Host, Port, Path, Query, URI),
+                    TScheme = list_to_atom(maps:get(scheme, URIMap)),
+                    THost = http_util:maybe_add_brackets(maps:get(host, URIMap), Brackets),
+                    TPort = maps:get(port, URIMap),
+                    TPath = maps:get(path, URIMap),
+                    TQuery = maps:get(query, URIMap, ""),
+                    NewURI = uri_string:normalize(
+                               uri_string:recompose(URIMap)),
+                    HostPort = http_request:normalize_host(TScheme, THost, TPort),
+                    NewHeaders =
+                        (Request#request.headers)#http_request_h{host = HostPort},
+                    NewRequest =
+                        Request#request{redircount =
+                                            Request#request.redircount+1,
+                                        scheme = TScheme,
+                                        headers = NewHeaders,
+                                        address = {THost,TPort},
+                                        path = TPath,
+                                        pquery = TQuery,
+                                        abs_uri = NewURI},
+                    {redirect, NewRequest, Data}
+            end
+    end.
+
+
+%% RFC3986 - 5.2.2.  Transform References
+resolve_uri(Scheme, Host, Port, Path, Query, URI) ->
+    resolve_uri(Scheme, Host, Port, Path, Query, URI, #{}).
+%%
+resolve_uri(Scheme, Host, Port, Path, Query, URI, Map0) ->
+    case maps:is_key(scheme, URI) of
+        true ->
+            Port = get_port(URI),
+            maybe_add_query(
+              Map0#{scheme => maps:get(scheme, URI),
+                   host => maps:get(host, URI),
+                   port => Port,
+                   path => maps:get(path, URI)},
+              URI);
+        false ->
+            Map = Map0#{scheme => Scheme},
+            resolve_authority(Host, Port, Path, Query, URI, Map)
+    end.
+
+
+get_port(URI) ->
+    Scheme = maps:get(scheme, URI),
+    case maps:get(port, URI, undefined) of
+        undefined ->
+            get_default_port(Scheme);
+        Port ->
+            Port
+    end.
+
+
+get_default_port("http") ->
+    80;
+get_default_port("https") ->
+    443.
+
+
+resolve_authority(Host, Port, Path, Query, RelURI, Map) ->
+    case maps:is_key(host, RelURI) of
+        true ->
+            Port = get_port(RelURI),
+            maybe_add_query(
+              Map#{host => maps:get(host, RelURI),
+                   port => Port,
+                   path => maps:get(path, RelURI)},
+              RelURI);
+        false ->
+            Map1 = Map#{host => Host,
+                    port => Port},
+            resolve_path(Path, Query, RelURI, Map1)
+    end.
+
+
+maybe_add_query(Map, RelURI) ->
+     case maps:is_key(query, RelURI) of
+         true ->
+             Map#{query => maps:get(query, RelURI)};
+         false ->
+             Map
+         end.
+
+
+resolve_path(Path, Query, RelURI, Map) ->
+    case maps:is_key(path, RelURI) of
+        true ->
+            Path1 = calculate_path(Path,  maps:get(path, RelURI)),
+            maybe_add_query(
+              Map#{path => Path1},
+              RelURI);
+        false ->
+            Map1 = Map#{path => Path},
+            resolve_query(Query, RelURI, Map1)
+    end.
+
+
+calculate_path(BaseP, RelP) ->
+    case starts_with_slash(RelP) of
+        true ->
+            RelP;
+        false ->
+            merge_paths(BaseP, RelP)
+    end.
+
+
+starts_with_slash([$/|_]) ->
+    true;
+starts_with_slash(<<$/,_/binary>>) ->
+    true;
+starts_with_slash(_) ->
+    false.
+
+
+%% RFC3986 - 5.2.3.  Merge Paths
+merge_paths("", RelP) ->
+    [$/|RelP];
+merge_paths(BaseP, RelP) when is_list(BaseP) ->
+    do_merge_paths(lists:reverse(BaseP), RelP);
+merge_paths(BaseP, RelP) when is_binary(BaseP) ->
+    B = binary_to_list(BaseP),
+    R = binary_to_list(RelP),
+    Res = merge_paths(B, R),
+    list_to_binary(Res).
+
+
+do_merge_paths([$/|_] = L, RelP) ->
+    lists:reverse(L) ++ RelP;
+do_merge_paths([_|T], RelP) ->
+    do_merge_paths(T, RelP).
+
+
+resolve_query(Query, RelURI, Map) ->
+    case maps:is_key(query, RelURI) of
+        true ->
+            Map#{query => maps:get(query, RelURI)};
+        false ->
+            Map#{query => Query}
     end.
 
-maybe_to_list(Port) when is_integer(Port) ->
-    integer_to_list(Port);
-maybe_to_list(Port) when is_list(Port) ->
+
+maybe_to_integer(Port) when is_list(Port) ->
+    {Port1, _} = string:to_integer(Port),
+    Port1;
+maybe_to_integer(Port) when is_integer(Port) ->
     Port.
 
-%%% Guessing that we received a relative URI, fix it to become an absoluteURI
-fix_relative_uri(Request, RedirUrl) ->
-    {Server, Port0} = Request#request.address,
-    Port = maybe_to_list(Port0),
-    Path = Request#request.path,
-    atom_to_list(Request#request.scheme) ++ "://" ++ Server ++ ":" ++ Port
-	++ Path ++ RedirUrl.
-    
+
 error(#request{id = Id}, Reason) ->
     {Id, {error, Reason}}.
 
@@ -478,18 +593,3 @@ format_response({StatusLine, Headers, Body}) ->
 		{Body, <<>>}
 	end,
     {{StatusLine, http_response:header_list(Headers), NewBody}, Data}.
-
-%%--------------------------------------------------------------------------
-%% These functions is just simple wrappers to parse specifically HTTP URIs
-%%--------------------------------------------------------------------------
-
-scheme_defaults() ->
-    [{http, 80}, {https, 443}].
-
-uri_parse(URI, Opts) ->
-    http_uri:parse(URI, [{scheme_defaults, scheme_defaults()} | Opts]).
-
-
-%%--------------------------------------------------------------------------
-
-
diff --git a/lib/inets/src/http_lib/http_util.erl b/lib/inets/src/http_lib/http_util.erl
index 487d04f7aa..5577b00cc8 100644
--- a/lib/inets/src/http_lib/http_util.erl
+++ b/lib/inets/src/http_lib/http_util.erl
@@ -27,7 +27,8 @@
 	 convert_month/1, 
 	 is_hostname/1,
 	 timestamp/0, timeout/2,
-	 html_encode/1
+	 html_encode/1,
+	 maybe_add_brackets/2
 	]).
 
 
@@ -194,6 +195,24 @@ html_encode(Chars) ->
     lists:append([char_to_html_entity(Char, Reserved) || Char <- Chars]).
 
 
+maybe_add_brackets(Addr, false) ->
+    Addr;
+maybe_add_brackets(Addr, true) when is_list(Addr) ->
+    case is_ipv6_address(Addr) of
+        true ->
+            [$[|Addr] ++ "]";
+        false ->
+            Addr
+    end;
+maybe_add_brackets(Addr, true) when is_binary(Addr) ->
+    case is_ipv6_address(Addr) of
+        true ->
+            <<$[,Addr/binary,$]>>;
+        false ->
+            Addr
+    end.
+
+
 %%%========================================================================
 %%% Internal functions
 %%%========================================================================
@@ -205,3 +224,14 @@ char_to_html_entity(Char, Reserved) ->
 	false ->
 	    [Char]
     end.
+
+is_ipv6_address(Addr) when is_binary(Addr) ->
+    B = binary_to_list(Addr),
+    is_ipv6_address(B);
+is_ipv6_address(Addr) when is_list(Addr) ->
+    case inet:parse_ipv6strict_address(Addr) of
+        {ok, _ } ->
+            true;
+        {error, _} ->
+            false
+    end.
diff --git a/lib/inets/test/httpc_SUITE.erl b/lib/inets/test/httpc_SUITE.erl
index 2ad041cc0d..0533b9ab70 100644
--- a/lib/inets/test/httpc_SUITE.erl
+++ b/lib/inets/test/httpc_SUITE.erl
@@ -58,6 +58,9 @@ all() ->
 groups() ->
     [
      {http, [], real_requests()},
+     %% process_leak_on_keepalive is depending on stream_fun_server_close
+     %% and it shall be the last test case in the suite otherwise cookie
+     %% will fail.
      {sim_http, [], only_simulated() ++ [process_leak_on_keepalive]},
      {https, [], real_requests()},
      {sim_https, [], only_simulated()},
@@ -68,6 +71,7 @@ real_requests()->
     [
      head,
      get,
+     get_query_string,
      post,
      delete,
      post_stream,
@@ -127,10 +131,12 @@ only_simulated() ->
      redirect_found,
      redirect_see_other,
      redirect_temporary_redirect,
+     redirect_relative_uri,
      port_in_host_header,
      redirect_port_in_host_header,
      relaxed,
      multipart_chunks,
+     get_space,
      stream_fun_server_close
     ].
 
@@ -243,6 +249,25 @@ get(Config) when is_list(Config) ->
 
     {ok, {{_,200,_}, [_ | _], BinBody}} =  httpc:request(get, Request, [], [{body_format, binary}]),
     true = is_binary(BinBody).
+
+
+get_query_string() ->
+    [{doc, "Test http get request with query string against local server"}].
+get_query_string(Config) when is_list(Config) ->
+    Request  = {url(group_name(Config), "/dummy.html?foo=bar", Config), []},
+    {ok, {{_,200,_}, [_ | _], Body = [_ | _]}} = httpc:request(get, Request, [], []),
+
+    inets_test_lib:check_body(Body).
+
+%%--------------------------------------------------------------------
+get_space() ->
+    [{"Test http get request with '%20' in the path of the URL."}].
+get_space(Config) when is_list(Config) ->
+    Request  = {url(group_name(Config), "/space%20.html", Config), []},
+    {ok, {{_,200,_}, [_ | _], Body = [_ | _]}} = httpc:request(get, Request, [], []),
+
+    inets_test_lib:check_body(Body).
+
 %%--------------------------------------------------------------------
 post() ->
     [{"Test http post request against local server. We do in this case "
@@ -576,7 +601,26 @@ redirect_temporary_redirect(Config) when is_list(Config) ->
     {ok, {{_,200,_}, [_ | _], [_|_]}}
 	= httpc:request(post, {URL307, [],"text/plain", "foobar"},
 			[], []).
+%%-------------------------------------------------------------------------
+redirect_relative_uri() ->
+    [{doc, "The server SHOULD generate a Location header field in the response "
+      "containing a preferred URI reference for the new permanent URI.  The user "
+      "agent MAY use the Location field value for automatic redirection.  The server's "
+      "response payload usually contains a short hypertext note with a "
+      "hyperlink to the new URI(s)."}].
+redirect_relative_uri(Config) when is_list(Config) ->
+
+    URL301 = url(group_name(Config), "/301_rel_uri.html", Config),
 
+    {ok, {{_,200,_}, [_ | _], [_|_]}}
+	= httpc:request(get, {URL301, []}, [], []),
+
+    {ok, {{_,200,_}, [_ | _], []}}
+	= httpc:request(head, {URL301, []}, [], []),
+
+    {ok, {{_,200,_}, [_ | _], [_|_]}}
+	= httpc:request(post, {URL301, [],"text/plain", "foobar"},
+			[], []).
 %%-------------------------------------------------------------------------
 redirect_loop() ->
     [{"doc, Test redirect loop detection"}].
@@ -1054,8 +1098,6 @@ remote_socket_close_async(Config) when is_list(Config) ->
 %%-------------------------------------------------------------------------
 
 process_leak_on_keepalive(Config) ->
-    {ok, ClosedSocket} = gen_tcp:listen(6666, [{active, false}]),
-    ok = gen_tcp:close(ClosedSocket),
     Request  = {url(group_name(Config), "/dummy.html", Config), []},
     HttpcHandlers0 = supervisor:which_children(httpc_handler_sup),
     {ok, {{_, 200, _}, _, Body}} = httpc:request(get, Request, [], []),
@@ -1067,11 +1109,10 @@ process_leak_on_keepalive(Config) ->
         ordsets:to_list(
           ordsets:subtract(ordsets:from_list(HttpcHandlers1),
                            ordsets:from_list(HttpcHandlers0))),
-    sys:replace_state(
-      Pid, fun (State) ->
-                   Session = element(3, State),
-                   setelement(3, State, Session#session{socket=ClosedSocket})
-           end),
+    State = sys:get_state(Pid),
+    #session{socket=Socket} = element(3, State),
+    gen_tcp:close(Socket),
+
     {ok, {{_, 200, _}, _, Body}} = httpc:request(get, Request, [], []),
     %% bad handler with the closed socket should get replaced by
     %% the new one, so children count should stay the same
@@ -1705,6 +1746,15 @@ content_length(["content-length:" ++ Value | _]) ->
 content_length([_Head | Tail]) ->
    content_length(Tail).
 
+handle_uri("GET","/dummy.html?foo=bar",_,_,_,_) ->
+    "HTTP/1.0 200 OK\r\n\r\nTEST";
+
+handle_uri("GET","/space%20.html",_,_,_,_) ->
+    Body = "<HTML><BODY>foobar</BODY></HTML>",
+    "HTTP/1.1 200 OK\r\n" ++
+        "Content-Length:" ++ integer_to_list(length(Body)) ++ "\r\n\r\n" ++
+        Body;
+
 handle_uri(_,"/just_close.html",_,_,_,_) ->
 		close;
 handle_uri(_,"/no_content.html",_,_,_,_) ->
@@ -1770,6 +1820,23 @@ handle_uri(_,"/301.html",Port,_,Socket,_) ->
 	"Content-Length:" ++ integer_to_list(length(Body))
 	++ "\r\n\r\n" ++ Body;
 
+
+handle_uri("HEAD","/301_rel_uri.html",_,_,_,_) ->
+    NewUri = "/dummy.html",
+    "HTTP/1.1 301 Moved Permanently\r\n" ++
+	"Location:" ++ NewUri ++  "\r\n" ++
+	"Content-Length:0\r\n\r\n";
+
+handle_uri(_,"/301_rel_uri.html",_,_,_,_) ->
+    NewUri = "/dummy.html",
+  Body = "<HTML><BODY><a href=" ++ NewUri ++
+	">New place</a></BODY></HTML>",
+    "HTTP/1.1 301 Moved Permanently\r\n" ++
+	"Location:" ++ NewUri ++  "\r\n" ++
+	"Content-Length:" ++ integer_to_list(length(Body))
+	++ "\r\n\r\n" ++ Body;
+
+
 handle_uri("HEAD","/302.html",Port,_,Socket,_) ->
     NewUri = url_start(Socket) ++
 	integer_to_list(Port) ++ "/dummy.html",
diff --git a/lib/inets/test/httpd_basic_SUITE.erl b/lib/inets/test/httpd_basic_SUITE.erl
index 931cd076cc..94d22ea76c 100644
--- a/lib/inets/test/httpd_basic_SUITE.erl
+++ b/lib/inets/test/httpd_basic_SUITE.erl
@@ -303,7 +303,10 @@ escaped_url_in_error_body(Config) when is_list(Config) ->
     %% Ask for a non-existing page(1)
     Path            = "/<b>this_is_bold<b>",
     HTMLEncodedPath = http_util:html_encode(Path),
-    URL2            = URL1 ++ Path,
+    URL2 = uri_string:recompose(#{scheme => "http",
+                                  host => "localhost",
+                                  port => Port,
+                                  path => Path}),
     {ok, {404, Body3}} = httpc:request(get, {URL2, []},
 				       [{url_encode,  true}, 
 					{version,     "HTTP/1.0"}],
diff --git a/lib/jinterface/test/nc_SUITE.erl b/lib/jinterface/test/nc_SUITE.erl
index 81944f71d4..daa17195ee 100644
--- a/lib/jinterface/test/nc_SUITE.erl
+++ b/lib/jinterface/test/nc_SUITE.erl
@@ -651,11 +651,10 @@ do_echo(DataList, Config, OutTrans, InTrans, ExtraArgs)
 echo_loop([D|Ds], Echoer, OutTrans, InTrans, TermAcc) ->
     OutMsg = OutTrans(D),
     Echoer ! OutMsg,
-    io:format("echo_server ~p: ~p ! ~P~n", [self(),Echoer,OutMsg,10]),
+    %%io:format("echo_server ~p: ~p ! ~P~n", [self(),Echoer,OutMsg,10]),
     receive
 	Reply ->
-	    io:format("echo_server ~p: receive ~P~n",
-		      [self(),Reply,10]),
+	    %%io:format("echo_server ~p: receive ~P~n", [self(),Reply,10]),
 	    InTrans(Echoer, D, Reply)
     end,
     Term = case OutMsg of
@@ -670,11 +669,10 @@ echo_loop(Cont, Echoer, OutTrans, InTrans, TermAcc)
   when is_function(Cont, 0) ->
     check_terms(Echoer, TermAcc),
     OutMsg = Echoer ! {self(),undefined,hash_clear},
-    io:format("echo_server ~p: ~p ! ~P~n", [self(),Echoer,OutMsg,10]),
+    %%io:format("echo_server ~p: ~p ! ~P~n", [self(),Echoer,OutMsg,10]),
     receive
 	{Echoer,hash_cleared,hash_clear}=Reply ->
-	    io:format("echo_server ~p: receive ~P~n",
-		      [self(),Reply,10]),
+	    %%io:format("echo_server ~p: receive ~P~n", [self(),Reply,10]),
 	    ok;
 	Other ->
 	    io:format("echo_server_terms unexpected ~p: receive ~P~n",
@@ -686,11 +684,10 @@ echo_loop(Cont, Echoer, OutTrans, InTrans, TermAcc)
 check_terms(Echoer, [Term | Rest]) ->
     OutMsg = {self(),Term,hash_lookup},
     Echoer ! OutMsg,
-    io:format("check_terms ~p: ~p ! ~P~n", [self(),Echoer,OutMsg,10]),
+    %%io:format("check_terms ~p: ~p ! ~P~n", [self(),Echoer,OutMsg,10]),
     receive
 	{Echoer,true,hash_lookup} = ReplyMsg ->
-	    io:format("check_terms ~p: receive ~P~n",
-		      [self(),ReplyMsg,10]),
+	    %%io:format("check_terms ~p: receive ~P~n", [self(),ReplyMsg,10]),
 	    check_terms(Echoer, Rest);
 	Other ->
 	    io:format("check_terms unexpected ~p: receive ~P~n",
diff --git a/lib/kernel/doc/src/file.xml b/lib/kernel/doc/src/file.xml
index b674b3ca93..58abb35428 100644
--- a/lib/kernel/doc/src/file.xml
+++ b/lib/kernel/doc/src/file.xml
@@ -33,15 +33,18 @@
   <description>
     <p>This module provides an interface to the file system.</p>
 
-    <p>On operating systems with thread support,
-      file operations can be performed in threads of their own, allowing
-      other Erlang processes to continue executing in parallel with
-      the file operations. See command-line flag
-      <c>+A</c> in <seealso marker="erts:erl"><c>erl(1)</c></seealso>.</p>
+    <warning>
+       <p>File operations are only guaranteed to appear atomic when going
+          through the same file server. A NIF or other OS process may observe
+          intermediate steps on certain operations on some operating systems,
+          eg. renaming an existing file on Windows, or
+          <seealso marker="#write_file_info/2"><c>write_file_info/2</c>
+          </seealso> on any OS at the time of writing.</p>
+    </warning>
 
     <p>Regarding filename encoding, the Erlang VM can operate in
     two modes. The current mode can be queried using function
-    <seealso marker="#native_name_encoding"><c>native_name_encoding/0</c></seealso>.
+    <seealso marker="#native_name_encoding/0"><c>native_name_encoding/0</c></seealso>.
     It returns <c>latin1</c> or <c>utf8</c>.</p>
 
     <p>In <c>latin1</c> mode, the Erlang VM does not change the
@@ -59,7 +62,7 @@
     terminal supports UTF-8, otherwise <c>latin1</c>. The default can
     be overridden using <c>+fnl</c> (to force <c>latin1</c> mode)
     or <c>+fnu</c> (to force <c>utf8</c> mode) when starting
-    <seealso marker="erts:erl"><c>erts:erl</c></seealso>.</p>
+    <seealso marker="erts:erl"><c>erl</c></seealso>.</p>
 
     <p>On operating systems with transparent naming, files can be
     inconsistently named, for example, some files are encoded in UTF-8 while
@@ -81,6 +84,23 @@
 
     <p>See also section <seealso marker="stdlib:unicode_usage#notes-about-raw-filenames">Notes About Raw Filenames</seealso> in the STDLIB User's Guide.</p>
 
+    <note><p>
+      File operations used to accept filenames containing
+      null characters (integer value zero). This caused
+      the name to be truncated and in some cases arguments
+      to primitive operations to be mixed up. Filenames
+      containing null characters inside the filename
+      are now <em>rejected</em> and will cause primitive
+      file operations fail.
+    </p></note>
+    <warning><p>
+      Currently null characters at the end of the filename
+      will be accepted by primitive file operations. Such
+      filenames are however still documented as invalid. The
+      implementation will also change in the future and
+      reject such filenames.
+    </p></warning>
+
   </description>
 
   <datatypes>
@@ -96,9 +116,21 @@
     </datatype>
     <datatype>
       <name name="filename"/>
+      <desc>
+        <p>
+	  See also the documentation of the
+	  <seealso marker="#type-name_all"><c>name_all()</c></seealso> type.
+	</p>
+      </desc>
     </datatype>
     <datatype>
       <name name="filename_all"/>
+      <desc>
+        <p>
+	  See also the documentation of the
+	  <seealso marker="#type-name_all"><c>name_all()</c></seealso> type.
+	</p>
+      </desc>
     </datatype>
     <datatype>
       <name name="io_device"/>
@@ -112,21 +144,23 @@
       <name name="name"/>
       <desc>
         <p>If VM is in Unicode filename mode, <c>string()</c> and <c>char()</c>
-          are allowed to be &gt; 255.
+          are allowed to be &gt; 255. See also the documentation of the
+	  <seealso marker="#type-name_all"><c>name_all()</c></seealso> type.
         </p>
       </desc>
     </datatype>
     <datatype>
       <name name="name_all"/>
       <desc>
-        <p>If VM is in Unicode filename mode, <c>string()</c> and <c>char()</c>
+        <p>If VM is in Unicode filename mode, characters
           are allowed to be &gt; 255.
           <c><anno>RawFilename</anno></c> is a filename not subject to
           Unicode translation,
           meaning that it can contain characters not conforming to
           the Unicode encoding expected from the file system
           (that is, non-UTF-8 characters although the VM is started
-          in Unicode filename mode).
+          in Unicode filename mode). Null characters (integer value zero)
+	  are <em>not</em> allowed in filenames (not even at the end).
         </p>
       </desc>
     </datatype>
@@ -1407,8 +1441,12 @@ f.txt:  {person, "kalle", 25}.
 	    which is 1970-01-01 00:00 UTC.</p></item>
 	  </taglist>
 	<p>Default is <c>{time, local}</c>.</p>
-        <p>If the option <c>raw</c> is set, the file server is not called
-          and only information about local files is returned.</p>
+        <p>If the option <c>raw</c> is set, the file server is not called and
+           only information about local files is returned. Note that this will
+           break this module's atomicity guarantees as it can race with a
+           concurrent call to
+           <seealso marker="#write_file_info/2"><c>write_file_info/1,2</c>
+           </seealso></p>
 	  <note>
           <p>As file times are stored in POSIX time on most OS, it is faster to
 	  query file information with option <c>posix</c>.</p>
@@ -1656,8 +1694,12 @@ f.txt:  {person, "kalle", 25}.
 	except that if <c><anno>Name</anno></c> is a symbolic link, information
 	about the link is returned in the <c>file_info</c> record and
           the <c>type</c> field of the record is set to <c>symlink</c>.</p>
-      <p>If the option <c>raw</c> is set, the file server is not called
-        and only information about local files is returned.</p>
+        <p>If the option <c>raw</c> is set, the file server is not called and
+           only information about local files is returned. Note that this will
+           break this module's atomicity guarantees as it can race with a
+           concurrent call to
+           <seealso marker="#write_file_info/2"><c>write_file_info/1,2</c>
+           </seealso></p>
         <p>If <c><anno>Name</anno></c> is not a symbolic link, this function returns
           the same result as <c>read_file_info/1</c>.
           On platforms that do not support symbolic links, this function
@@ -1795,24 +1837,16 @@ f.txt:  {person, "kalle", 25}.
 	<p>The file used must be opened using the <c>raw</c> flag, and the process
 	calling <c>sendfile</c> must be the controlling process of the socket.
 	See <seealso marker="gen_tcp#controlling_process-2"><c>gen_tcp:controlling_process/2</c></seealso>.</p>
-	<p>If the OS used does not support <c>sendfile</c>, an Erlang fallback
-	using
-	<seealso marker="#read/2"><c>read/2</c></seealso> and
-	<seealso marker="gen_tcp#send/2"><c>gen_tcp:send/2</c></seealso> is used.</p>
+	<p>If the OS used does not support non-blocking <c>sendfile</c>, an
+	Erlang fallback using <seealso marker="#read/2"><c>read/2</c></seealso>
+	and <seealso marker="gen_tcp#send/2"><c>gen_tcp:send/2</c></seealso> is
+        used.</p>
 	<p>The option list can contain the following options:</p>
 	<taglist>
           <tag><c>chunk_size</c></tag>
           <item><p>The chunk size used by the Erlang fallback to send
 	  data. If using the fallback, set this to a value
 	  that comfortably fits in the systems memory. Default is 20 MB.</p></item>
-	  <tag><c>use_threads</c></tag>
-          <item><p>Instructs the emulator to use the <c>async</c> thread pool for the
-	  <c>sendfile</c> system call. This can be useful if the OS you are running
-	  on does not properly support non-blocking <c>sendfile</c> calls. Notice that
-	  using <c>async</c> threads potentially makes your system vulnerable to slow
-	  client attacks. If set to <c>true</c> and no <c>async</c> threads are available,
-	  the <c>sendfile</c> call returns <c>{error,einval}</c>.
-	  Introduced in Erlang/OTP 17.0. Default is <c>false</c>.</p></item>
 	</taglist>
       </desc>
     </func>
@@ -1825,7 +1859,7 @@ f.txt:  {person, "kalle", 25}.
         <p>The functions in the module <c>file</c> usually treat binaries
           as raw filenames, that is, they are passed "as is" even when the
 	  encoding of the binary does not agree with
-	  <seealso marker="#native_name_encoding"><c>native_name_encoding()</c></seealso>.
+	  <seealso marker="#native_name_encoding/0"><c>native_name_encoding()</c></seealso>.
           However, this function expects binaries to be encoded according to the
           value returned by <c>native_name_encoding()</c>.</p>
         <p>Typical error reasons are:</p>
@@ -2117,144 +2151,77 @@ f.txt:  {person, "kalle", 25}.
 
   <section>
     <title>Performance</title>
-    <p>Some operating system file operations, for example, a
-      <c>sync/1</c> or <c>close/1</c> on a huge file, can block their
-      calling thread for seconds. If this affects the emulator main
-      thread, the response time is no longer in the order of
-      milliseconds, depending on the definition of "soft" in soft
-      real-time system.</p>
-    <p>If the device driver thread pool is active, file operations are
-      done through those threads instead, so the emulator can go on
-      executing Erlang processes. Unfortunately, the time for serving a
-      file operation increases because of the extra scheduling required
-      from the operating system.</p>
-    <p>If the device driver thread pool is disabled or of size 0, large
-      file reads and writes are segmented into many smaller, which
-      enable the emulator to serve other processes during the file
-      operation. This has the same effect as when using the thread
-      pool, but with larger overhead. Other file operations, for
-      example, <c>sync/1</c> or <c>close/1</c> on a huge file, still are
-      a problem.</p>
-    <p>For increased performance, raw files are recommended. Raw files
-      use the file system of the host machine of the node.</p>
+    <p>For increased performance, raw files are recommended.</p>
+    <p>A normal file is really a process so it can be used as an I/O
+       device (see <seealso marker="stdlib:io"><c>io</c></seealso>).
+       Therefore, when data is written to a normal file, the sending of the
+       data to the file process, copies all data that are not binaries. Opening
+       the file in binary mode and writing binaries is therefore recommended.
+       If the file is opened on another node, or if the file server runs as
+       slave to the file server of another node, also binaries are copied.</p>
     <note>
-      <p>
-	For normal files (non-raw), the file server is used to find the files,
-	and if the node is running its file server as slave to the file server
-	of another node, and the other node runs on some other host machine,
-	they can have different file systems.
-        However, this is seldom a problem.</p>
+      <p>Raw files use the file system of the host machine of the node.
+         For normal files (non-raw), the file server is used to find the files,
+         and if the node is running its file server as slave to the file server
+         of another node, and the other node runs on some other host machine,
+         they can have different file systems.
+         However, this is seldom a problem.</p>
     </note>
-    <p>A normal file is really a process so it can be used as an I/O
-      device (see
-      <seealso marker="stdlib:io"><c>io</c></seealso>).
-      Therefore, when data is written to a
-      normal file, the sending of the data to the file process, copies 
-      all data that are not binaries. Opening the file in binary mode
-      and writing binaries is therefore recommended. If the file is
-      opened on another node, or if the file server runs as slave to
-      the file server of another node, also binaries are copied.</p>
-    <p>Caching data to reduce the number of file operations, or rather
-      the number of calls to the file driver, generally increases
-      performance. The following function writes 4 MBytes in 23
-      seconds when tested:</p>
+    <p><seealso marker="#open/2"><c>open/2</c></seealso> can be given the
+       options <c>delayed_write</c> and <c>read_ahead</c> to turn on caching,
+       which will reduce the number of operating system calls and greatly
+       improve performance for small reads and writes. However, the overhead
+       won't disappear completely and it's best to keep the number of file
+       operations to a minimum. As a contrived example, the following function
+       writes 4MB in 2.5 seconds when tested:</p>
+
     <code type="none"><![CDATA[
-create_file_slow(Name, N) when integer(N), N >= 0 ->
-    {ok, FD} = file:open(Name, [raw, write, delayed_write, binary]),
-    ok = create_file_slow(FD, 0, N),
-    ok = ?FILE_MODULE:close(FD),
-    ok.
-      
-create_file_slow(FD, M, M) ->
+create_file_slow(Name) ->
+    {ok, Fd} = file:open(Name, [raw, write, delayed_write, binary]),
+    create_file_slow_1(Fd, 4 bsl 20),
+    file:close(Fd).
+
+create_file_slow_1(_Fd, 0) ->
     ok;
-create_file_slow(FD, M, N) ->
-    ok = file:write(FD, <<M:32/unsigned>>),
-    create_file_slow(FD, M+1, N).]]></code>
+create_file_slow_1(Fd, M) ->
+    ok = file:write(Fd, <<0>>),
+    create_file_slow_1(Fd, M - 1).]]></code>
+
+    <p>The following functionally equivalent code writes 128 bytes per call
+       to <seealso marker="#write/2"><c>write/2</c></seealso> and so does the
+       same work in 0.08 seconds, which is roughly 30 times faster:</p>
 
-    <p>The following, functionally equivalent, function collects 1024
-      entries into a list of 128 32-byte binaries before each call to
-      <seealso marker="#write/2"><c>write/2</c></seealso> and so
-      does the same work in 0.52 seconds,
-      which is 44 times faster:</p>
     <code type="none"><![CDATA[
-create_file(Name, N) when integer(N), N >= 0 ->
-    {ok, FD} = file:open(Name, [raw, write, delayed_write, binary]),
-    ok = create_file(FD, 0, N),
-    ok = ?FILE_MODULE:close(FD),
+create_file(Name) ->
+    {ok, Fd} = file:open(Name, [raw, write, delayed_write, binary]),
+    create_file_1(Fd, 4 bsl 20),
+    file:close(Fd),
     ok.
-      
-create_file(FD, M, M) ->
+
+create_file_1(_Fd, 0) ->
     ok;
-create_file(FD, M, N) when M + 1024 =&lt; N ->
-    create_file(FD, M, M + 1024, []),
-    create_file(FD, M + 1024, N);
-create_file(FD, M, N) ->
-    create_file(FD, M, N, []).
-      
-create_file(FD, M, M, R) ->
-    ok = file:write(FD, R);
-create_file(FD, M, N0, R) when M + 8 =&lt; N0 ->
-    N1  = N0-1,  N2  = N0-2,  N3  = N0-3,  N4  = N0-4, 
-    N5  = N0-5,  N6  = N0-6,  N7  = N0-7,  N8  = N0-8, 
-    create_file(FD, M, N8, 
-                [<<N8:32/unsigned,  N7:32/unsigned, 
-                   N6:32/unsigned,  N5:32/unsigned, 
-                   N4:32/unsigned,  N3:32/unsigned, 
-                   N2:32/unsigned,  N1:32/unsigned>> | R]);
-create_file(FD, M, N0, R) ->
-    N1 = N0-1,
-    create_file(FD, M, N1, [<<N1:32/unsigned>> | R]).]]></code>
+create_file_1(Fd, M) when M >= 128 ->
+    ok = file:write(Fd, <<0:(128)/unit:8>>),
+    create_file_1(Fd, M - 128);
+create_file_1(Fd, M) ->
+    ok = file:write(Fd, <<0:(M)/unit:8>>),
+    create_file_1(Fd, M - 1).]]></code>
 
-    <note>
-      <p>Trust only your own benchmarks. If the list length in 
-        <c>create_file/2</c> above is increased, it runs slightly
-        faster, but consumes more memory and causes more memory
-        fragmentation. How much this affects your application is
-        something that this simple benchmark cannot predict.</p>
-      <p>If the size of each binary is increased to 64 bytes, it
-        also runs slightly faster, but the code is then twice as clumsy.
-        In the current implementation, binaries larger than 64 bytes are
-        stored in memory common to all processes and not copied when
-        sent between processes, while these smaller binaries are stored
-        on the process heap and copied when sent like any other term.</p>
-      <p>So, with a binary size of 68 bytes, <c>create_file/2</c> runs
-        30 percent slower than with 64 bytes, and causes much more
-        memory fragmentation. Notice that if the binaries were to be sent
-        between processes (for example, a non-raw file), the results
-        would probably be completely different.</p>
-    </note>
-    <p>A raw file is really a port. When writing data to a port, it is
-      efficient to write a list of binaries. It is not needed to
-      flatten a deep list before writing. On Unix hosts, scatter output,
-      which writes a set of buffers in one operation, is used when
-      possible. In this way <c>write(FD, [Bin1, Bin2 | Bin3])</c>
-      writes the contents of the binaries without copying the data
-      at all, except for perhaps deep down in the operating system
-      kernel.</p>
-    <p>For raw files, <c>pwrite/2</c> and <c>pread/2</c> are
-      efficiently implemented. The file driver is called only once for
-      the whole operation, and the list iteration is done in the file
-      driver.</p>
-    <p>The options <c>delayed_write</c> and <c>read_ahead</c> to 
-      <seealso marker="#open/2"><c>open/2</c></seealso>
-      make the file driver cache data to reduce
-      the number of operating system calls. The function
-      <c>create_file/2</c> in the recent example takes 60 seconds
-      without option <c>delayed_write</c>, which is 2.6
-      times slower.</p>
-    <p>As a bad example, <c>create_file_slow/2</c>
-      without options <c>raw</c>, <c>binary</c>, and <c>delayed_write</c>,
-      meaning it calls <c>open(Name, [write])</c>, needs
-      1 min 20 seconds for the job, which is 3.5 times slower than
-      the first example, and 150 times slower than the optimized
-      <c>create_file/2</c>.</p>
-      <warning>
-	<p>If an error occurs when accessing an open file with module
-      <seealso marker="stdlib:io"><c>io</c></seealso>,
-      the process handling the file exits. The dead
-      file process can hang if a process tries to access it later.
-      This will be fixed in a future release.</p>
-      </warning>
+    <p>When writing data it's generally more efficient to write a list of
+       binaries rather than a list of integers. It is not needed to
+       flatten a deep list before writing. On Unix hosts, scatter output,
+       which writes a set of buffers in one operation, is used when
+       possible. In this way <c>write(FD, [Bin1, Bin2 | Bin3])</c>
+       writes the contents of the binaries without copying the data
+       at all, except for perhaps deep down in the operating system
+       kernel.</p>
+    <warning>
+        <p>If an error occurs when accessing an open file with module
+           <seealso marker="stdlib:io"><c>io</c></seealso>, the process
+           handling the file exits. The dead file process can hang if a process
+           tries to access it later. This will be fixed in a future release.
+           </p>
+    </warning>
   </section>
 
   <section>
diff --git a/lib/kernel/doc/src/inet_res.xml b/lib/kernel/doc/src/inet_res.xml
index 4ada4203c0..3454e3c6f9 100644
--- a/lib/kernel/doc/src/inet_res.xml
+++ b/lib/kernel/doc/src/inet_res.xml
@@ -130,7 +130,7 @@ dns_header() = DnsHeader
     inet_dns:header(DnsHeader) ->
         [ {id, integer()}
         | {qr, boolean()}
-        | {opcode, 'query' | iquery | status | integer()}
+        | {opcode, query | iquery | status | integer()}
         | {aa, boolean()}
         | {tc, boolean()}
         | {rd, boolean()}
diff --git a/lib/kernel/doc/src/net_kernel.xml b/lib/kernel/doc/src/net_kernel.xml
index 0b94fc0fa6..94c8fb9e20 100644
--- a/lib/kernel/doc/src/net_kernel.xml
+++ b/lib/kernel/doc/src/net_kernel.xml
@@ -230,7 +230,12 @@ $ <input>erl -sname foobar</input></pre>
           <item>
             <p>The tuple <c>{nodedown_reason, Reason}</c> is included in
               <c>InfoList</c> in <c>nodedown</c> messages.</p>
-            <p><c>Reason</c> can be any of the following:</p>
+            <p>
+	      <c>Reason</c> can, depending on which
+	      distribution module or process that is used be any term,
+	      but for the standard TCP distribution module it is
+	      any of the following:
+	    </p>
             <taglist>
               <tag><c>connection_setup_failed</c></tag>
               <item><p>The connection setup failed (after <c>nodeup</c>
diff --git a/lib/kernel/doc/src/os.xml b/lib/kernel/doc/src/os.xml
index 0e9add4161..0a08e2c78a 100644
--- a/lib/kernel/doc/src/os.xml
+++ b/lib/kernel/doc/src/os.xml
@@ -36,8 +36,99 @@
       only run on a specific platform. On the other hand, with careful
       use, these functions can be of help in enabling a program to run on
       most platforms.</p>
+
+    <note>
+      <p>
+	File operations used to accept filenames containing
+	null characters (integer value zero). This caused
+	the name to be truncated and in some cases arguments
+	to primitive operations to be mixed up. Filenames
+	containing null characters inside the filename
+	are now <em>rejected</em> and will cause primitive
+	file operations to fail.
+      </p>
+      <p>
+	Also environment variable operations used to accept
+	names and values of environment variables containing
+	null characters (integer value zero). This caused
+	operations to silently produce erroneous results.
+	Environment variable names and values containing
+	null characters inside the name or value are now
+	<em>rejected</em> and will cause environment variable
+	operations to fail.
+      </p>
+    </note>
+    <warning>
+      <p>
+	Currently null characters at the end of filenames,
+	environment variable names and values will be accepted
+	by the primitive operations. Such filenames, environment
+	variable names and values are however still documented as
+	invalid. The implementation will also change in the
+	future and reject such filenames, environment variable
+	names and values.
+      </p>
+    </warning>
   </description>
 
+  <datatypes>
+    <datatype>
+      <name name="env_var_name"/>
+      <desc>
+        <p>A string containing valid characters on the specific
+	OS for environment variable names using
+	<seealso marker="file#native_name_encoding/0"><c>file:native_name_encoding()</c></seealso>
+	encoding. Note that specifically null characters (integer
+	value zero) and <c>$=</c> characters are not allowed.
+	However, note that not all invalid characters necessarily
+	will cause the primitiv operations to fail, but may instead
+	produce invalid results.
+	</p>
+      </desc>
+    </datatype>
+    <datatype>
+      <name name="env_var_value"/>
+      <desc>
+        <p>A string containing valid characters on the specific
+	OS for environment variable values using
+	<seealso marker="file#native_name_encoding/0"><c>file:native_name_encoding()</c></seealso>
+	encoding. Note that specifically null characters (integer
+	value zero) are not allowed. However, note that not all
+	invalid characters necessarily will cause the primitiv
+	operations to fail, but may instead produce invalid results.
+	</p>
+      </desc>
+    </datatype>
+    <datatype>
+      <name name="env_var_name_value"/>
+      <desc>
+        <p>
+	  Assuming that environment variables has been correctly
+	  set, a strings containing valid characters on the specific
+	  OS for environment variable names and values using
+	  <seealso marker="file#native_name_encoding/0"><c>file:native_name_encoding()</c></seealso>
+	  encoding. The first <c>$=</c> characters appearing in
+	  the string separates environment variable name (on the
+	  left) from environment variable value (on the right).
+	</p>
+      </desc>
+    </datatype>
+    <datatype>
+      <name name="command_input"/>
+      <desc>
+        <p>All characters needs to be valid characters on the
+	specific OS using
+	<seealso marker="file#native_name_encoding/0"><c>file:native_name_encoding()</c></seealso>
+	encoding. Note that specifically null characters (integer
+	value zero) are not allowed. However, note that not all
+	invalid characters not necessarily will cause
+	<seealso marker="#cmd/1"><c>os:cmd/1</c></seealso>
+	to fail, but may instead produce invalid results.
+	</p>
+      </desc>
+    </datatype>
+  </datatypes>
+ 
   <funcs>
     <func>
       <name name="cmd" arity="1"/>
@@ -49,6 +140,15 @@
           result as a string. This function is a replacement of
           the previous function <c>unix:cmd/1</c>; they are equivalent on a
           Unix platform.</p>
+	  <warning><p>Previous implementation used to allow all characters
+	  as long as they were integer values greater than or equal to zero.
+	  This sometimes lead to unwanted results since null characters
+	  (integer value zero) often are interpreted as string termination.
+	  Current implementation still accepts null characters at the end
+	  of <c><anno>Command</anno></c> even though the documentation
+	  states that no null characters are allowed. This will however
+	  be changed in the future so that no null characters at all will
+	  be accepted.</p></warning>
         <p><em>Examples:</em></p>
         <code type="none">
 LsOut = os:cmd("ls"), % on unix platform
@@ -152,6 +252,15 @@ DirOut = os:cmd("dir"), % on Win32 platform</code>
 	<p>On Unix platforms, the environment is set using UTF-8 encoding
 	  if Unicode filename translation is in effect. On Windows, the
 	  environment is set using wide character interfaces.</p>
+	  <note>
+	    <p>
+	      <c><anno>VarName</anno></c> is not allowed to contain
+	      an <c>$=</c> character. Previous implementations used
+	      to just let the <c>$=</c> character through which
+	      silently caused erroneous results. Current implementation
+	      will instead throw a <c>badarg</c> exception.
+	    </p>
+	  </note>
       </desc>
     </func>
 
diff --git a/lib/kernel/examples/Makefile b/lib/kernel/examples/Makefile
index 26ec58f571..f86e662838 100644
--- a/lib/kernel/examples/Makefile
+++ b/lib/kernel/examples/Makefile
@@ -45,7 +45,7 @@ RELSYSDIR = $(RELEASE_PATH)/lib/kernel-$(KERNEL_VSN)/examples
 # Pack and install the complete directory structure from 
 # here (CWD) and down, for all examples.
 
-EXAMPLES  = uds_dist
+EXAMPLES  = uds_dist gen_tcp_dist
 
 release_spec:
 	$(INSTALL_DIR) "$(RELSYSDIR)"
diff --git a/lib/kernel/examples/gen_tcp_dist/Makefile b/lib/kernel/examples/gen_tcp_dist/Makefile
new file mode 100644
index 0000000000..65513a1729
--- /dev/null
+++ b/lib/kernel/examples/gen_tcp_dist/Makefile
@@ -0,0 +1,20 @@
+RM=rm -f
+CP=cp
+EBIN=ebin
+ERLC=erlc
+# Works if building in open source source tree
+KERNEL_INCLUDE=$(ERL_TOP)/lib/kernel/include
+ERLCFLAGS+= -W -I$(KERNEL_INCLUDE)
+
+MODULES=gen_tcp_dist
+
+TARGET_FILES=$(MODULES:%=$(EBIN)/%.beam)
+
+opt: $(TARGET_FILES)
+
+$(EBIN)/%.beam: src/%.erl
+	$(ERLC) $(ERLCFLAGS) -o$(EBIN) $<
+
+clean:
+	$(RM) $(TARGET_FILES)
+
diff --git a/lib/kernel/examples/gen_tcp_dist/ebin/.gitignore b/lib/kernel/examples/gen_tcp_dist/ebin/.gitignore
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/lib/kernel/examples/gen_tcp_dist/ebin/.gitignore
diff --git a/lib/kernel/examples/gen_tcp_dist/src/gen_tcp_dist.erl b/lib/kernel/examples/gen_tcp_dist/src/gen_tcp_dist.erl
new file mode 100644
index 0000000000..98554ed805
--- /dev/null
+++ b/lib/kernel/examples/gen_tcp_dist/src/gen_tcp_dist.erl
@@ -0,0 +1,781 @@
+%%
+%% %CopyrightBegin%
+%% 
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%% 
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%% 
+%% %CopyrightEnd%
+%%
+-module(gen_tcp_dist).
+
+%%
+%% This is an example of how to plug in an arbitrary distribution
+%% carrier for Erlang using distribution processes.
+%%
+%% This example uses gen_tcp for transportation of data, but
+%% you can use whatever underlying protocol you want as long
+%% as your implementation reliably delivers data chunks to the
+%% receiving VM in the order they were sent from the sending
+%% VM.
+%%
+%% This code is a rewrite of the lib/kernel/src/inet_tcp_dist.erl
+%% distribution impementation for TCP used by default. That
+%% implementation use distribution ports instead of distribution
+%% processes and is more efficient compared to this implementation.
+%% This since this implementation more or less gets the
+%% distribution processes in between the VM and the ports without
+%% any gain specific gain.
+%%
+
+-export([listen/1, accept/1, accept_connection/5,
+	 setup/5, close/1, select/1, is_node_name/1]).
+
+%% Optional
+-export([setopts/2, getopts/2]).
+
+%% internal exports
+
+-export([dist_cntrlr_setup/1, dist_cntrlr_input_setup/3,
+         dist_cntrlr_tick_handler/1]).
+
+-export([accept_loop/2,do_accept/6,do_setup/6]).
+
+-import(error_logger,[error_msg/2]).
+
+-include("net_address.hrl").
+
+-include("dist.hrl").
+-include("dist_util.hrl").
+
+%% ------------------------------------------------------------
+%%  Select this protocol based on node name
+%%  select(Node) => Bool
+%% ------------------------------------------------------------
+
+select(Node) ->
+    case split_node(atom_to_list(Node), $@, []) of
+	[_, Host] ->
+	    case inet:getaddr(Host, inet) of
+                {ok,_} -> true;
+                _ -> false
+            end;
+	_ -> false
+    end.
+
+%% ------------------------------------------------------------
+%% Create the listen socket, i.e. the port that this erlang
+%% node is accessible through.
+%% ------------------------------------------------------------
+
+listen(Name) ->
+    case do_listen([binary, {active, false}, {packet,2}, {reuseaddr, true}]) of
+	{ok, Socket} ->
+	    TcpAddress = get_tcp_address(Socket),
+	    {_,Port} = TcpAddress#net_address.address,
+	    ErlEpmd = net_kernel:epmd_module(),
+	    case ErlEpmd:register_node(Name, Port) of
+		{ok, Creation} ->
+		    {ok, {Socket, TcpAddress, Creation}};
+		Error ->
+		    Error
+	    end;
+	Error ->
+	    Error
+    end.
+
+do_listen(Options) ->
+    {First,Last} = case application:get_env(kernel,inet_dist_listen_min) of
+		       {ok,N} when is_integer(N) ->
+			   case application:get_env(kernel,
+						    inet_dist_listen_max) of
+			       {ok,M} when is_integer(M) ->
+				   {N,M};
+			       _ ->
+				   {N,N}
+			   end;
+		       _ ->
+			   {0,0}
+		   end,
+    do_listen(First, Last, listen_options([{backlog,128}|Options])).
+
+do_listen(First,Last,_) when First > Last ->
+    {error,eaddrinuse};
+do_listen(First,Last,Options) ->
+    case gen_tcp:listen(First, Options) of
+	{error, eaddrinuse} ->
+	    do_listen(First+1,Last,Options);
+	Other ->
+	    Other
+    end.
+
+listen_options(Opts0) ->
+    Opts1 =
+	case application:get_env(kernel, inet_dist_use_interface) of
+	    {ok, Ip} ->
+		[{ip, Ip} | Opts0];
+	    _ ->
+		Opts0
+	end,
+    case application:get_env(kernel, inet_dist_listen_options) of
+	{ok,ListenOpts} ->
+	    ListenOpts ++ Opts1;
+	_ ->
+	    Opts1
+    end.
+
+
+%% ------------------------------------------------------------
+%% Accepts new connection attempts from other Erlang nodes.
+%% ------------------------------------------------------------
+
+accept(Listen) ->
+    spawn_opt(?MODULE, accept_loop, [self(), Listen], [link, {priority, max}]).
+
+accept_loop(Kernel, Listen) ->
+    ?trace("~p~n",[{?MODULE, accept_loop, self()}]),
+    case gen_tcp:accept(Listen) of
+	{ok, Socket} ->
+            DistCtrl = spawn_dist_cntrlr(Socket), 
+            ?trace("~p~n",[{?MODULE, accept_loop, accepted, Socket, DistCtrl, self()}]),
+	    flush_controller(DistCtrl, Socket),
+	    gen_tcp:controlling_process(Socket, DistCtrl),
+	    flush_controller(DistCtrl, Socket),
+	    Kernel ! {accept,self(),DistCtrl,inet,tcp},
+            receive
+                {Kernel, controller, Pid} ->
+                    call_ctrlr(DistCtrl, {supervisor, Pid}),
+                    Pid ! {self(), controller};
+                {Kernel, unsupported_protocol} ->
+                    exit(unsupported_protocol)
+            end,
+	    accept_loop(Kernel, Listen);
+	Error ->
+	    exit(Error)
+    end.
+
+flush_controller(Pid, Socket) ->
+    receive
+	{tcp, Socket, Data} ->
+	    Pid ! {tcp, Socket, Data},
+	    flush_controller(Pid, Socket);
+	{tcp_closed, Socket} ->
+	    Pid ! {tcp_closed, Socket},
+	    flush_controller(Pid, Socket)
+    after 0 ->
+	    ok
+    end.
+
+%% ------------------------------------------------------------
+%% Accepts a new connection attempt from another Erlang node.
+%% Performs the handshake with the other side.
+%% ------------------------------------------------------------
+
+accept_connection(AcceptPid, DistCtrl, MyNode, Allowed, SetupTime) ->
+    spawn_opt(?MODULE, do_accept,
+	      [self(), AcceptPid, DistCtrl, MyNode, Allowed, SetupTime],
+	      [link, {priority, max}]).
+
+do_accept(Kernel, AcceptPid, DistCtrl, MyNode, Allowed, SetupTime) ->
+    ?trace("~p~n",[{?MODULE, do_accept, self(), MyNode}]),
+    receive
+	{AcceptPid, controller} ->
+	    Timer = dist_util:start_timer(SetupTime),
+	    case check_ip(DistCtrl) of
+		true ->
+                    HSData0 = hs_data_common(DistCtrl),
+		    HSData = HSData0#hs_data{kernel_pid = Kernel,
+                                             this_node = MyNode,
+                                             socket = DistCtrl,
+                                             timer = Timer,
+                                             this_flags = 0,
+                                             allowed = Allowed},
+		    dist_util:handshake_other_started(HSData);
+		{false,IP} ->
+		    error_msg("** Connection attempt from "
+			      "disallowed IP ~w ** ~n", [IP]),
+		    ?shutdown(no_node)
+	    end
+    end.
+
+%% we may not always want the nodelay behaviour
+%% for performance reasons
+
+nodelay() ->
+    case application:get_env(kernel, dist_nodelay) of
+	undefined ->
+	    {nodelay, true};
+	{ok, true} ->
+	    {nodelay, true};
+	{ok, false} ->
+	    {nodelay, false};
+	_ ->
+	    {nodelay, true}
+    end.
+
+%% ------------------------------------------------------------
+%% Setup a new connection to another Erlang node.
+%% Performs the handshake with the other side.
+%% ------------------------------------------------------------
+
+setup(Node, Type, MyNode, LongOrShortNames,SetupTime) ->
+    spawn_opt(?MODULE, do_setup, 
+	      [self(), Node, Type, MyNode, LongOrShortNames, SetupTime],
+	      [link, {priority, max}]).
+
+do_setup(Kernel, Node, Type, MyNode, LongOrShortNames, SetupTime) ->
+    ?trace("~p~n",[{?MODULE, do_setup, self(), Node}]),
+    [Name, Address] = splitnode(Node, LongOrShortNames),
+    case inet:getaddr(Address, inet) of
+	{ok, Ip} ->
+	    Timer = dist_util:start_timer(SetupTime),
+	    ErlEpmd = net_kernel:epmd_module(),
+	    case ErlEpmd:port_please(Name, Ip) of
+		{port, TcpPort, Version} ->
+		    ?trace("port_please(~p) -> version ~p~n", 
+			   [Node,Version]),
+		    dist_util:reset_timer(Timer),
+		    case
+			gen_tcp:connect(
+			  Ip, TcpPort,
+			  connect_options([binary, {active, false}, {packet, 2}]))
+		    of
+			{ok, Socket} ->
+                            DistCtrl = spawn_dist_cntrlr(Socket), 
+                            call_ctrlr(DistCtrl, {supervisor, self()}),
+                            flush_controller(DistCtrl, Socket),
+                            gen_tcp:controlling_process(Socket, DistCtrl),
+                            flush_controller(DistCtrl, Socket),
+                            HSData0 = hs_data_common(DistCtrl),
+			    HSData = HSData0#hs_data{kernel_pid = Kernel,
+                                                     other_node = Node,
+                                                     this_node = MyNode,
+                                                     socket = DistCtrl,
+                                                     timer = Timer,
+                                                     this_flags = 0,
+                                                     other_version = Version,
+                                                     request_type = Type},
+			    dist_util:handshake_we_started(HSData);
+			_ ->
+			    %% Other Node may have closed since 
+			    %% port_please !
+			    ?trace("other node (~p) "
+				   "closed since port_please.~n", 
+				   [Node]),
+			    ?shutdown(Node)
+		    end;
+		_ ->
+		    ?trace("port_please (~p) "
+			   "failed.~n", [Node]),
+		    ?shutdown(Node)
+	    end;
+	_Other ->
+	    ?trace("inet_getaddr(~p) "
+		   "failed (~p).~n", [Node,_Other]),
+	    ?shutdown(Node)
+    end.
+
+connect_options(Opts) ->
+    case application:get_env(kernel, inet_dist_connect_options) of
+	{ok,ConnectOpts} ->
+	    ConnectOpts ++ Opts;
+	_ ->
+	    Opts
+    end.
+
+%%
+%% Close a socket.
+%%
+close(Listen) ->
+    gen_tcp:close(Listen).
+
+
+%% If Node is illegal terminate the connection setup!!
+splitnode(Node, LongOrShortNames) ->
+    case split_node(atom_to_list(Node), $@, []) of
+	[Name|Tail] when Tail =/= [] ->
+	    Host = lists:append(Tail),
+	    case split_node(Host, $., []) of
+		[_] when LongOrShortNames =:= longnames ->
+                    case inet:parse_address(Host) of
+                        {ok, _} ->
+                            [Name, Host];
+                        _ ->
+                            error_msg("** System running to use "
+                                      "fully qualified "
+                                      "hostnames **~n"
+                                      "** Hostname ~ts is illegal **~n",
+                                      [Host]),
+                            ?shutdown(Node)
+                    end;
+		L when length(L) > 1, LongOrShortNames =:= shortnames ->
+		    error_msg("** System NOT running to use fully qualified "
+			      "hostnames **~n"
+			      "** Hostname ~ts is illegal **~n",
+			      [Host]),
+		    ?shutdown(Node);
+		_ ->
+		    [Name, Host]
+	    end;
+	[_] ->
+	    error_msg("** Nodename ~p illegal, no '@' character **~n",
+		      [Node]),
+	    ?shutdown(Node);
+	_ ->
+	    error_msg("** Nodename ~p illegal **~n", [Node]),
+	    ?shutdown(Node)
+    end.
+
+split_node([Chr|T], Chr, Ack) -> [lists:reverse(Ack)|split_node(T, Chr, [])];
+split_node([H|T], Chr, Ack)   -> split_node(T, Chr, [H|Ack]);
+split_node([], _, Ack)        -> [lists:reverse(Ack)].
+
+%% ------------------------------------------------------------
+%% Fetch local information about a Socket.
+%% ------------------------------------------------------------
+get_tcp_address(Socket) ->
+    {ok, Address} = inet:sockname(Socket),
+    {ok, Host} = inet:gethostname(),
+    #net_address {
+		  address = Address,
+		  host = Host,
+		  protocol = tcp,
+		  family = inet
+		 }.
+
+%% ------------------------------------------------------------
+%% Do only accept new connection attempts from nodes at our
+%% own LAN, if the check_ip environment parameter is true.
+%% ------------------------------------------------------------
+check_ip(DistCtrl) ->
+    case application:get_env(check_ip) of
+	{ok, true} ->
+	    case get_ifs(DistCtrl) of
+		{ok, IFs, IP} ->
+		    check_ip(IFs, IP);
+		_ ->
+		    ?shutdown(no_node)
+	    end;
+	_ ->
+	    true
+    end.
+
+get_ifs(DistCtrl) ->
+    Socket = call_ctrlr(DistCtrl, socket),
+    case inet:peername(Socket) of
+	{ok, {IP, _}} ->
+	    case inet:getif(Socket) of
+		{ok, IFs} -> {ok, IFs, IP};
+		Error     -> Error
+	    end;
+	Error ->
+	    Error
+    end.
+
+check_ip([{OwnIP, _, Netmask}|IFs], PeerIP) ->
+    case {inet_tcp:mask(Netmask, PeerIP), inet_tcp:mask(Netmask, OwnIP)} of
+	{M, M} -> true;
+	_      -> check_ip(IFs, PeerIP)
+    end;
+check_ip([], PeerIP) ->
+    {false, PeerIP}.
+    
+is_node_name(Node) when is_atom(Node) ->
+    case split_node(atom_to_list(Node), $@, []) of
+	[_, _Host] -> true;
+	_ -> false
+    end;
+is_node_name(_Node) ->
+    false.
+
+hs_data_common(DistCtrl) ->
+    TickHandler = call_ctrlr(DistCtrl, tick_handler),
+    Socket = call_ctrlr(DistCtrl, socket),
+    #hs_data{f_send = send_fun(),
+             f_recv = recv_fun(),
+             f_setopts_pre_nodeup = setopts_pre_nodeup_fun(),
+             f_setopts_post_nodeup = setopts_post_nodeup_fun(),
+             f_getll = getll_fun(),
+             f_handshake_complete = handshake_complete_fun(),
+             f_address = address_fun(),
+             mf_setopts = setopts_fun(DistCtrl, Socket),
+             mf_getopts = getopts_fun(DistCtrl, Socket),
+             mf_getstat = getstat_fun(DistCtrl, Socket),
+             mf_tick = tick_fun(DistCtrl, TickHandler)}.
+
+%%% ------------------------------------------------------------
+%%% Distribution controller processes
+%%% ------------------------------------------------------------
+
+%%
+%% There will be five parties working together when the
+%% connection is up:
+%% - The gen_tcp socket. Providing a tcp/ip connection
+%%   to the other node.
+%% - The output handler. It will dispatch all outgoing
+%%   traffic from the VM to the gen_tcp socket. This
+%%   process is registered as distribution controller
+%%   for this channel with the VM.
+%% - The input handler. It will dispatch all incoming
+%%   traffic from the gen_tcp socket to the VM. This
+%%   process is also the socket owner and receives
+%%   incoming traffic using active-N.
+%% - The tick handler. Dispatches asynchronous tick
+%%   requests to the socket. It executes on max priority
+%%   since it is important to get ticks through to the
+%%   other end.
+%% - The channel supervisor (provided by dist_util). It
+%%   monitors traffic. Issue tick requests to the tick
+%%   handler when no outgoing traffic is seen and bring
+%%   the connection down if no incoming traffic is seen.
+%%   This process also executes on max priority.
+%%
+%%   These parties are linked togheter so should one
+%%   of them fail, all of them are terminated and the
+%%   connection is taken down.
+%%
+
+%% In order to avoid issues with lingering signal binaries
+%% we enable off-heap message queue data as well as fullsweep
+%% after 0. The fullsweeps will be cheap since we have more
+%% or less no live data.
+-define(DIST_CNTRL_COMMON_SPAWN_OPTS,
+        [{message_queue_data, off_heap},
+         {fullsweep_after, 0}]).
+
+tick_fun(DistCtrl, TickHandler) ->
+    fun (Ctrl) when Ctrl == DistCtrl ->
+            TickHandler ! tick
+    end.
+
+getstat_fun(DistCtrl, Socket) ->
+    fun (Ctrl) when Ctrl == DistCtrl ->
+            case inet:getstat(Socket, [recv_cnt, send_cnt, send_pend]) of
+                {ok, Stat} ->
+                    split_stat(Stat,0,0,0);
+                Error ->
+                    Error
+            end
+    end.
+
+split_stat([{recv_cnt, R}|Stat], _, W, P) ->
+    split_stat(Stat, R, W, P);
+split_stat([{send_cnt, W}|Stat], R, _, P) ->
+    split_stat(Stat, R, W, P);
+split_stat([{send_pend, P}|Stat], R, W, _) ->
+    split_stat(Stat, R, W, P);
+split_stat([], R, W, P) ->
+    {ok, R, W, P}.
+
+setopts_fun(DistCtrl, Socket) ->
+    fun (Ctrl, Opts) when Ctrl == DistCtrl ->
+            setopts(Socket, Opts)
+    end.
+
+getopts_fun(DistCtrl, Socket) ->
+    fun (Ctrl, Opts) when Ctrl == DistCtrl ->
+            getopts(Socket, Opts)
+    end.
+
+setopts(S, Opts) ->
+    case [Opt || {K,_}=Opt <- Opts,
+		 K =:= active orelse K =:= deliver orelse K =:= packet] of
+	[] -> inet:setopts(S,Opts);
+	Opts1 -> {error, {badopts,Opts1}}
+    end.
+
+getopts(S, Opts) ->
+    inet:getopts(S, Opts).
+
+send_fun() ->
+    fun (Ctrlr, Packet) ->
+            call_ctrlr(Ctrlr, {send, Packet})
+    end.
+
+recv_fun() ->
+    fun (Ctrlr, Length, Timeout) ->
+            case call_ctrlr(Ctrlr, {recv, Length, Timeout}) of
+                {ok, Bin} when is_binary(Bin) ->
+                    {ok, binary_to_list(Bin)};
+                Other ->
+                    Other
+            end
+    end.
+
+getll_fun() ->
+    fun (Ctrlr) ->
+            call_ctrlr(Ctrlr, getll)
+    end.
+
+address_fun() ->
+    fun (Ctrlr, Node) ->
+            case call_ctrlr(Ctrlr, {address, Node}) of
+                {error, no_node} -> %% No '@' or more than one '@' in node name.
+		    ?shutdown(no_node);
+                Res ->
+                    Res
+            end
+    end.
+
+setopts_pre_nodeup_fun() ->
+    fun (Ctrlr) ->
+            call_ctrlr(Ctrlr, pre_nodeup)
+    end.
+
+setopts_post_nodeup_fun() ->
+    fun (Ctrlr) ->
+            call_ctrlr(Ctrlr, post_nodeup)
+    end.
+
+handshake_complete_fun() ->
+    fun (Ctrlr, Node, DHandle) ->
+            call_ctrlr(Ctrlr, {handshake_complete, Node, DHandle})
+    end.
+
+call_ctrlr(Ctrlr, Msg) ->
+    Ref = erlang:monitor(process, Ctrlr),
+    Ctrlr ! {Ref, self(), Msg},
+    receive
+        {Ref, Res} ->
+            erlang:demonitor(Ref, [flush]),
+            Res;
+        {'DOWN', Ref, process, Ctrlr, Reason} ->
+            exit({dist_controller_exit, Reason})
+    end.
+
+%%
+%% The tick handler process writes a tick to the
+%% socket when it receives a 'tick' message from
+%% the connection supervisor.
+%%
+%% We are not allowed to block the connection
+%% superviser when writing a tick and we also want
+%% the tick to go through even during a heavily
+%% loaded system. gen_tcp does not have a
+%% non-blocking send operation exposed in its API
+%% and we don't want to run the distribution
+%% controller under high priority. Therefore this
+%% sparate process with max prio that dispatches
+%% ticks.
+%%
+dist_cntrlr_tick_handler(Socket) ->
+    receive
+        tick ->
+            %% May block due to busy port...
+            sock_send(Socket, "");
+        _ ->
+            ok
+    end,
+    dist_cntrlr_tick_handler(Socket).
+
+spawn_dist_cntrlr(Socket) ->
+    spawn_opt(?MODULE, dist_cntrlr_setup, [Socket],
+              [{priority, max}] ++ ?DIST_CNTRL_COMMON_SPAWN_OPTS).
+
+dist_cntrlr_setup(Socket) ->
+    TickHandler = spawn_opt(?MODULE, dist_cntrlr_tick_handler,
+                            [Socket], 
+                            [link, {priority, max}] 
+                            ++ ?DIST_CNTRL_COMMON_SPAWN_OPTS),
+    dist_cntrlr_setup_loop(Socket, TickHandler, undefined).
+
+%%
+%% During the handshake phase we loop in dist_cntrlr_setup().
+%% When the connection is up we spawn an input handler and
+%% continue as output handler.
+%%
+dist_cntrlr_setup_loop(Socket, TickHandler, Sup) ->
+    receive
+        {tcp_closed, Socket} ->
+            exit(connection_closed);
+
+        {Ref, From, {supervisor, Pid}} ->
+            Res = link(Pid),
+            From ! {Ref, Res},
+            dist_cntrlr_setup_loop(Socket, TickHandler, Pid);
+
+        {Ref, From, tick_handler} ->
+            From ! {Ref, TickHandler},
+            dist_cntrlr_setup_loop(Socket, TickHandler, Sup);
+
+        {Ref, From, socket} ->
+            From ! {Ref, Socket},
+            dist_cntrlr_setup_loop(Socket, TickHandler, Sup);
+
+        {Ref, From, {send, Packet}} ->
+            Res = gen_tcp:send(Socket, Packet),
+            From ! {Ref, Res},
+            dist_cntrlr_setup_loop(Socket, TickHandler, Sup);
+
+        {Ref, From, {recv, Length, Timeout}} ->
+            Res = gen_tcp:recv(Socket, Length, Timeout),
+            From ! {Ref, Res},
+            dist_cntrlr_setup_loop(Socket, TickHandler, Sup);
+
+        {Ref, From, getll} ->
+            From ! {Ref, {ok, self()}},
+            dist_cntrlr_setup_loop(Socket, TickHandler, Sup);
+
+        {Ref, From, {address, Node}} ->
+            Res = case inet:peername(Socket) of
+                      {ok, Address} ->
+                          case split_node(atom_to_list(Node), $@, []) of
+                              [_,Host] ->
+                                  #net_address{address=Address,host=Host,
+                                               protocol=tcp, family=inet};
+                              _ ->
+                                  {error, no_node}
+                          end
+                  end,
+            From ! {Ref, Res},
+            dist_cntrlr_setup_loop(Socket, TickHandler, Sup);
+
+        {Ref, From, pre_nodeup} ->
+            Res = inet:setopts(Socket, 
+                               [{active, false},
+                                {packet, 4},
+                                nodelay()]),
+            From ! {Ref, Res},
+            dist_cntrlr_setup_loop(Socket, TickHandler, Sup);
+
+        {Ref, From, post_nodeup} ->
+            Res = inet:setopts(Socket,
+                               [{active, false},
+                                {packet, 4},
+                                nodelay()]),
+            From ! {Ref, Res},
+            dist_cntrlr_setup_loop(Socket, TickHandler, Sup);
+
+        {Ref, From, {handshake_complete, _Node, DHandle}} ->
+            From ! {Ref, ok},
+            %% Handshake complete! Begin dispatching traffic...
+
+            %% We use separate process for dispatching input. This
+            %% is not necessary, but it enables parallel execution
+            %% of independent work loads at the same time as it
+            %% simplifies the the implementation...
+            InputHandler = spawn_opt(?MODULE, dist_cntrlr_input_setup,
+                                     [DHandle, Socket, Sup],
+                                     [link] ++ ?DIST_CNTRL_COMMON_SPAWN_OPTS),
+
+	    flush_controller(InputHandler, Socket),
+	    gen_tcp:controlling_process(Socket, InputHandler),
+	    flush_controller(InputHandler, Socket),
+
+            ok = erlang:dist_ctrl_input_handler(DHandle, InputHandler),
+
+            InputHandler ! DHandle,
+
+            %% From now on we execute on normal priority
+            process_flag(priority, normal),
+            erlang:dist_ctrl_get_data_notification(DHandle),
+            dist_cntrlr_output_loop(DHandle, Socket)
+    end.
+
+%% We use active 10 for good throughput while still
+%% maintaining back-pressure if the input controller
+%% isn't able to handle all incoming messages...
+-define(ACTIVE_INPUT, 10).
+
+dist_cntrlr_input_setup(DHandle, Socket, Sup) ->
+    link(Sup),
+    %% Ensure we don't try to put data before registerd
+    %% as input handler...
+    receive
+        DHandle ->
+            dist_cntrlr_input_loop(DHandle, Socket, 0)
+    end.
+
+dist_cntrlr_input_loop(DHandle, Socket, N) when N =< ?ACTIVE_INPUT/2 ->
+    inet:setopts(Socket, [{active, ?ACTIVE_INPUT - N}]),
+    dist_cntrlr_input_loop(DHandle, Socket, ?ACTIVE_INPUT);
+dist_cntrlr_input_loop(DHandle, Socket, N) ->
+    receive
+        {tcp_closed, Socket} ->
+            %% Connection to remote node terminated...
+            exit(connection_closed);
+
+        {tcp, Socket, Data} ->
+            %% Incoming data from remote node...
+            try erlang:dist_ctrl_put_data(DHandle, Data)
+            catch _ : _ -> death_row()
+            end,
+            dist_cntrlr_input_loop(DHandle, Socket, N-1);
+
+        _ ->
+            %% Ignore...
+            dist_cntrlr_input_loop(DHandle, Socket, N)
+    end.
+
+dist_cntrlr_send_data(DHandle, Socket) ->
+    case erlang:dist_ctrl_get_data(DHandle) of
+        none ->
+            erlang:dist_ctrl_get_data_notification(DHandle);
+        Data ->
+            sock_send(Socket, Data),
+            dist_cntrlr_send_data(DHandle, Socket)
+    end.
+
+
+dist_cntrlr_output_loop(DHandle, Socket) ->
+    receive
+        dist_data ->
+            %% Outgoing data from this node...
+            try dist_cntrlr_send_data(DHandle, Socket)
+            catch _ : _ -> death_row()
+            end,
+            dist_cntrlr_output_loop(DHandle, Socket);
+
+        {send, From, Ref, Data} ->
+            %% This is for testing only!
+            %%
+            %% Needed by some OTP distribution
+            %% test suites...
+            sock_send(Socket, Data),
+            From ! {Ref, ok},
+            dist_cntrlr_output_loop(DHandle, Socket);
+
+        _ ->
+            %% Drop garbage message...
+            dist_cntrlr_output_loop(DHandle, Socket)
+
+    end.
+
+sock_send(Socket, Data) ->
+    try gen_tcp:send(Socket, Data) of
+        ok -> ok;
+        {error, Reason} -> death_row({send_error, Reason})
+    catch
+        Type : Reason -> death_row({send_error, {Type, Reason}})
+    end.
+
+death_row() ->
+    death_row(connection_closed).
+
+death_row(normal) ->
+    %% We do not want to exit with normal
+    %% exit reason since it wont bring down
+    %% linked processes...
+    death_row();
+death_row(Reason) ->
+    %% When the connection is on its way down operations
+    %% begin to fail. We catch the failures and call
+    %% this function waiting for termination. We should
+    %% be terminated by one of our links to the other
+    %% involved parties that began bringing the
+    %% connection down. By waiting for termination we
+    %% avoid altering the exit reason for the connection
+    %% teardown. We however limit the wait to 5 seconds
+    %% and bring down the connection ourselves if not
+    %% terminated...
+    receive after 5000 -> exit(Reason) end.
diff --git a/lib/kernel/include/dist.hrl b/lib/kernel/include/dist.hrl
index d6bccdf474..db4a5eaebc 100644
--- a/lib/kernel/include/dist.hrl
+++ b/lib/kernel/include/dist.hrl
@@ -40,3 +40,33 @@
 -define(DFLAG_UTF8_ATOMS, 16#10000).
 -define(DFLAG_MAP_TAG, 16#20000).
 -define(DFLAG_BIG_CREATION, 16#40000).
+-define(DFLAG_SEND_SENDER, 16#80000).
+
+%% DFLAGs that require strict ordering or:ed together...
+-define(DFLAGS_STRICT_ORDER_DELIVERY,
+        ?DFLAG_DIST_HDR_ATOM_CACHE).
+
+
+%% Also update dflag2str() in ../src/dist_util.erl
+%% when adding flags...
+
+-define(DFLAGS_ALL,
+        (?DFLAG_PUBLISHED
+             bor ?DFLAG_ATOM_CACHE
+             bor ?DFLAG_EXTENDED_REFERENCES
+             bor ?DFLAG_DIST_MONITOR
+             bor ?DFLAG_FUN_TAGS
+             bor ?DFLAG_DIST_MONITOR_NAME
+             bor ?DFLAG_HIDDEN_ATOM_CACHE
+             bor ?DFLAG_NEW_FUN_TAGS
+             bor ?DFLAG_EXTENDED_PIDS_PORTS
+             bor ?DFLAG_EXPORT_PTR_TAG
+             bor ?DFLAG_BIT_BINARIES
+             bor ?DFLAG_NEW_FLOATS
+             bor ?DFLAG_UNICODE_IO
+             bor ?DFLAG_DIST_HDR_ATOM_CACHE
+             bor ?DFLAG_SMALL_ATOM_TAGS
+             bor ?DFLAG_UTF8_ATOMS
+             bor ?DFLAG_MAP_TAG
+             bor ?DFLAG_BIG_CREATION
+             bor ?DFLAG_SEND_SENDER)).
diff --git a/lib/kernel/include/dist_util.hrl b/lib/kernel/include/dist_util.hrl
index e3d2fe0eb6..eeb0f8dd43 100644
--- a/lib/kernel/include/dist_util.hrl
+++ b/lib/kernel/include/dist_util.hrl
@@ -29,9 +29,9 @@
 -endif.
 
 -ifdef(dist_trace).
--define(trace(Fmt,Args), io:format("~p ~p:~s",[erlang:timestamp(),node(),lists:flatten(io_lib:format(Fmt, Args))])).
+-define(trace(Fmt,Args), io:format("~p ~p:~s",[erlang:convert_time_unit(erlang:monotonic_time()-erlang:system_info(start_time), native, microsecond),node(),lists:flatten(io_lib:format(Fmt, Args))])).
 % Use the one below for config-file (early boot) connection tracing
-%-define(trace(Fmt,Args), erlang:display([erlang:now(),node(),lists:flatten(io_lib:format(Fmt, Args))])).
+%-define(trace(Fmt,Args), erlang:display([erlang:convert_time_unit(erlang:monotonic_time()-erlang:system_info(start_time), native, microsecond),node(),lists:flatten(io_lib:format(Fmt, Args))])).
 -define(trace_factor,8).
 -else.
 -define(trace(Fmt,Args), ok).
@@ -78,7 +78,13 @@
 
 	  %% New in kernel-5.1 (OTP 19.1):
 	  mf_setopts,        %% netkernel:setopts on active connection
-	  mf_getopts         %% netkernel:getopts on active connection
+	  mf_getopts,         %% netkernel:getopts on active connection
+
+          %% New in kernel-6.0 (OTP 21.0)
+          f_handshake_complete, %% Notify handshake complete
+          add_flags,         %% dflags to add
+          reject_flags,      %% dflags not to use (not all can be rejected)
+          require_flags     %% dflags that are required
 }).
 	  
 
diff --git a/lib/kernel/src/Makefile b/lib/kernel/src/Makefile
index 5946620f0f..0bc9f121a0 100644
--- a/lib/kernel/src/Makefile
+++ b/lib/kernel/src/Makefile
@@ -106,6 +106,7 @@ MODULES = \
 	inet_sctp \
 	kernel \
 	kernel_config \
+	kernel_refc \
 	local_udp \
 	local_tcp \
 	net \
@@ -120,6 +121,13 @@ MODULES = \
 	user \
 	user_drv \
 	user_sup \
+	raw_file_io \
+	raw_file_io_compressed \
+	raw_file_io_inflate \
+	raw_file_io_deflate \
+	raw_file_io_delayed \
+	raw_file_io_list \
+	raw_file_io_raw \
 	wrap_log_reader
 
 HRL_FILES= ../include/file.hrl ../include/inet.hrl ../include/inet_sctp.hrl \
@@ -226,7 +234,8 @@ $(EBIN)/disk_log_server.beam: disk_log.hrl
 $(EBIN)/dist_util.beam: ../include/dist_util.hrl ../include/dist.hrl
 $(EBIN)/erl_boot_server.beam: inet_boot.hrl
 $(EBIN)/erl_epmd.beam: inet_int.hrl erl_epmd.hrl
-$(EBIN)/file.beam: ../include/file.hrl
+$(EBIN)/file.beam: ../include/file.hrl file_int.hrl
+$(EBIN)/file_io_server.beam: ../include/file.hrl file_int.hrl
 $(EBIN)/gen_tcp.beam: inet_int.hrl
 $(EBIN)/gen_udp.beam: inet_int.hrl
 $(EBIN)/gen_sctp.beam: ../include/inet_sctp.hrl
@@ -254,3 +263,10 @@ $(EBIN)/net_kernel.beam: ../include/net_address.hrl
 $(EBIN)/os.beam: ../include/file.hrl
 $(EBIN)/ram_file.beam: ../include/file.hrl
 $(EBIN)/wrap_log_reader.beam: disk_log.hrl ../include/file.hrl
+$(EBIN)/raw_file_io.beam: ../include/file.hrl file_int.hrl
+$(EBIN)/raw_file_io_compressed.beam: ../include/file.hrl file_int.hrl
+$(EBIN)/raw_file_io_inflate.beam: ../include/file.hrl file_int.hrl
+$(EBIN)/raw_file_io_deflate.beam: ../include/file.hrl file_int.hrl
+$(EBIN)/raw_file_io_delayed.beam: ../include/file.hrl file_int.hrl
+$(EBIN)/raw_file_io_list.beam: ../include/file.hrl file_int.hrl
+$(EBIN)/raw_file_io_raw.beam: ../include/file.hrl file_int.hrl
diff --git a/lib/kernel/src/dist_util.erl b/lib/kernel/src/dist_util.erl
index b3507e5d13..fb9f7fd7eb 100644
--- a/lib/kernel/src/dist_util.erl
+++ b/lib/kernel/src/dist_util.erl
@@ -74,6 +74,48 @@
 	       ticked = 0
 	       }).
 
+dflag2str(?DFLAG_PUBLISHED) ->
+    "PUBLISHED";
+dflag2str(?DFLAG_ATOM_CACHE) ->
+    "ATOM_CACHE";
+dflag2str(?DFLAG_EXTENDED_REFERENCES) ->
+    "EXTENDED_REFERENCES";
+dflag2str(?DFLAG_DIST_MONITOR) ->
+    "DIST_MONITOR";
+dflag2str(?DFLAG_FUN_TAGS) ->
+    "FUN_TAGS";
+dflag2str(?DFLAG_DIST_MONITOR_NAME) ->
+    "DIST_MONITOR_NAME";
+dflag2str(?DFLAG_HIDDEN_ATOM_CACHE) ->
+    "HIDDEN_ATOM_CACHE";
+dflag2str(?DFLAG_NEW_FUN_TAGS) ->
+    "NEW_FUN_TAGS";
+dflag2str(?DFLAG_EXTENDED_PIDS_PORTS) ->
+    "EXTENDED_PIDS_PORTS";
+dflag2str(?DFLAG_EXPORT_PTR_TAG) ->
+    "EXPORT_PTR_TAG";
+dflag2str(?DFLAG_BIT_BINARIES) ->
+    "BIT_BINARIES";
+dflag2str(?DFLAG_NEW_FLOATS) ->
+    "NEW_FLOATS";
+dflag2str(?DFLAG_UNICODE_IO) ->
+    "UNICODE_IO";
+dflag2str(?DFLAG_DIST_HDR_ATOM_CACHE) ->
+    "DIST_HDR_ATOM_CACHE";
+dflag2str(?DFLAG_SMALL_ATOM_TAGS) ->
+    "SMALL_ATOM_TAGS";
+dflag2str(?DFLAG_UTF8_ATOMS) ->
+    "UTF8_ATOMS";
+dflag2str(?DFLAG_MAP_TAG) ->
+    "MAP_TAG";
+dflag2str(?DFLAG_BIG_CREATION) ->
+    "BIG_CREATION";
+dflag2str(?DFLAG_SEND_SENDER) ->
+    "SEND_SENDER";
+dflag2str(_) ->
+    "UNKNOWN".
+
+
 remove_flag(Flag, Flags) ->
     case Flags band Flag of
 	0 ->
@@ -82,13 +124,13 @@ remove_flag(Flag, Flags) ->
 	    Flags - Flag
     end.
 
-adjust_flags(ThisFlags, OtherFlags) ->
+adjust_flags(ThisFlags, OtherFlags, RejectFlags) ->
     case (?DFLAG_PUBLISHED band ThisFlags) band OtherFlags of
 	0 ->
 	    {remove_flag(?DFLAG_PUBLISHED, ThisFlags),
 	     remove_flag(?DFLAG_PUBLISHED, OtherFlags)};
 	_ ->
-	    {ThisFlags, OtherFlags}
+	    {ThisFlags, OtherFlags band (bnot RejectFlags)}
     end.
 
 publish_flag(hidden, _) ->
@@ -101,36 +143,71 @@ publish_flag(_, OtherNode) ->
 	    0
     end.
 
-make_this_flags(RequestType, OtherNode) ->
-    publish_flag(RequestType, OtherNode) bor
-	%% The parenthesis below makes the compiler generate better code.
-	(?DFLAG_EXPORT_PTR_TAG bor
-	 ?DFLAG_EXTENDED_PIDS_PORTS bor
-	 ?DFLAG_EXTENDED_REFERENCES bor
-	 ?DFLAG_DIST_MONITOR bor
-	 ?DFLAG_FUN_TAGS bor
-	 ?DFLAG_DIST_MONITOR_NAME bor
-	 ?DFLAG_HIDDEN_ATOM_CACHE bor
-	 ?DFLAG_NEW_FUN_TAGS bor
-	 ?DFLAG_BIT_BINARIES bor
-	 ?DFLAG_NEW_FLOATS bor
-	 ?DFLAG_UNICODE_IO bor
-	 ?DFLAG_DIST_HDR_ATOM_CACHE bor
-	 ?DFLAG_SMALL_ATOM_TAGS bor
-	 ?DFLAG_UTF8_ATOMS bor
-	 ?DFLAG_MAP_TAG bor
-	 ?DFLAG_BIG_CREATION).
-
-handshake_other_started(#hs_data{request_type=ReqType}=HSData0) ->
+-define(DFLAGS_REMOVABLE,
+        (?DFLAG_DIST_HDR_ATOM_CACHE
+             bor ?DFLAG_HIDDEN_ATOM_CACHE
+             bor ?DFLAG_ATOM_CACHE)).
+
+-define(DFLAGS_ADDABLE,
+        (?DFLAGS_ALL
+             band (bnot (?DFLAG_PUBLISHED
+                             bor ?DFLAG_HIDDEN_ATOM_CACHE
+                             bor ?DFLAG_ATOM_CACHE)))).
+
+-define(DFLAGS_THIS_DEFAULT,
+        (?DFLAG_EXPORT_PTR_TAG
+             bor ?DFLAG_EXTENDED_PIDS_PORTS
+             bor ?DFLAG_EXTENDED_REFERENCES
+             bor ?DFLAG_DIST_MONITOR
+             bor ?DFLAG_FUN_TAGS
+             bor ?DFLAG_DIST_MONITOR_NAME
+             bor ?DFLAG_NEW_FUN_TAGS
+             bor ?DFLAG_BIT_BINARIES
+             bor ?DFLAG_NEW_FLOATS
+             bor ?DFLAG_UNICODE_IO
+             bor ?DFLAG_DIST_HDR_ATOM_CACHE
+             bor ?DFLAG_SMALL_ATOM_TAGS
+             bor ?DFLAG_UTF8_ATOMS
+             bor ?DFLAG_MAP_TAG
+             bor ?DFLAG_BIG_CREATION
+             bor ?DFLAG_SEND_SENDER)).
+
+make_this_flags(RequestType, AddFlags, RemoveFlags, OtherNode) ->
+    case RemoveFlags band (bnot ?DFLAGS_REMOVABLE) of
+        0 -> ok;
+        Rerror -> exit({"Rejecting non rejectable flags", Rerror})
+    end,
+    case AddFlags band (bnot ?DFLAGS_ADDABLE) of
+        0 -> ok;
+        Aerror -> exit({"Adding non addable flags", Aerror})
+    end,
+    Flgs0 = ?DFLAGS_THIS_DEFAULT,
+    Flgs1 = Flgs0 bor publish_flag(RequestType, OtherNode),
+    Flgs2 = Flgs1 bor AddFlags,
+    Flgs3 = Flgs2 band (bnot (?DFLAG_HIDDEN_ATOM_CACHE
+                                  bor ?DFLAG_ATOM_CACHE)),
+    Flgs3 band (bnot RemoveFlags).
+
+handshake_other_started(#hs_data{request_type=ReqType,
+                                 add_flags=AddFlgs0,
+                                 reject_flags=RejFlgs0,
+                                 require_flags=ReqFlgs0}=HSData0) ->
+    AddFlgs = convert_flags(AddFlgs0),
+    RejFlgs = convert_flags(RejFlgs0),
+    ReqFlgs = convert_flags(ReqFlgs0),
     {PreOtherFlags,Node,Version} = recv_name(HSData0),
-    PreThisFlags = make_this_flags(ReqType, Node),
+    PreThisFlags = make_this_flags(ReqType, AddFlgs, RejFlgs, Node),
     {ThisFlags, OtherFlags} = adjust_flags(PreThisFlags,
-					   PreOtherFlags),
+					   PreOtherFlags,
+                                           RejFlgs),
     HSData = HSData0#hs_data{this_flags=ThisFlags,
 			     other_flags=OtherFlags,
 			     other_version=Version,
 			     other_node=Node,
-			     other_started=true},
+			     other_started=true,
+                             add_flags=AddFlgs,
+                             reject_flags=RejFlgs,
+                             require_flags=ReqFlgs},
     check_dflags(HSData),
     is_allowed(HSData),
     ?debug({"MD5 connection from ~p (V~p)~n",
@@ -165,23 +242,19 @@ is_allowed(#hs_data{other_node = Node,
     end.
 
 %%
-%% Check that both nodes can handle the same types of extended
-%% node containers. If they can not, abort the connection.
+%% Check mandatory flags...
 %%
 check_dflags(#hs_data{other_node = Node,
                       other_flags = OtherFlags,
-                      other_started = OtherStarted} = HSData) ->
-
-    Mandatory = [{?DFLAG_EXTENDED_REFERENCES, "EXTENDED_REFERENCES"},
-                 {?DFLAG_EXTENDED_PIDS_PORTS, "EXTENDED_PIDS_PORTS"},
-                 {?DFLAG_UTF8_ATOMS, "UTF8_ATOMS"}],
-    Missing = lists:filtermap(fun({Bit, Str}) ->
-                                      case Bit band OtherFlags of
-                                          Bit -> false;
-                                          0 -> {true, Str}
-                                      end
-                              end,
-                              Mandatory),
+                      other_started = OtherStarted,
+                      require_flags = RequiredFlags} = HSData) ->
+    Mandatory = ((?DFLAG_EXTENDED_REFERENCES
+                      bor ?DFLAG_EXTENDED_PIDS_PORTS
+                      bor ?DFLAG_UTF8_ATOMS
+                      bor ?DFLAG_NEW_FUN_TAGS)
+                     bor RequiredFlags),
+    Missing = check_mandatory(0, ?DFLAGS_ALL, Mandatory,
+                              OtherFlags, []),
     case Missing of
         [] ->
             ok;
@@ -201,6 +274,22 @@ check_dflags(#hs_data{other_node = Node,
 	    ?shutdown2(Node, {check_dflags_failed, Missing})
     end.
 
+check_mandatory(_Bit, 0, _Mandatory, _OtherFlags, Missing) ->
+    Missing;
+check_mandatory(Bit, Left, Mandatory, OtherFlags, Missing) ->
+    DFlag = (1 bsl Bit),
+    NewLeft = Left band (bnot DFlag),
+    NewMissing = case {DFlag band Mandatory,
+                       DFlag band OtherFlags} of
+                     {DFlag, 0} ->
+                         %% Mandatory and missing...
+                         [dflag2str(DFlag) | Missing];
+                     _ ->
+                         %% Not mandatory or present...
+                         Missing
+                 end,
+    check_mandatory(Bit+1, NewLeft, Mandatory, OtherFlags, NewMissing).
+                    
 
 %% No nodedown will be sent if we fail before this process has
 %% succeeded to mark the node as pending.
@@ -314,13 +403,24 @@ flush_down() ->
     end.
 
 handshake_we_started(#hs_data{request_type=ReqType,
-			      other_node=Node}=PreHSData) ->
-    PreThisFlags = make_this_flags(ReqType, Node),
-    HSData = PreHSData#hs_data{this_flags=PreThisFlags},
+			      other_node=Node,
+                              add_flags=AddFlgs0,
+                              reject_flags=RejFlgs0,
+                              require_flags=ReqFlgs0}=PreHSData) ->
+    AddFlgs = convert_flags(AddFlgs0),
+    RejFlgs = convert_flags(RejFlgs0),
+    ReqFlgs = convert_flags(ReqFlgs0),
+    PreThisFlags = make_this_flags(ReqType, AddFlgs, RejFlgs, Node),
+    HSData = PreHSData#hs_data{this_flags = PreThisFlags,
+                               add_flags = AddFlgs,
+                               reject_flags = RejFlgs,
+                               require_flags = ReqFlgs},
     send_name(HSData),
     recv_status(HSData),
     {PreOtherFlags,ChallengeA} = recv_challenge(HSData),
-    {ThisFlags,OtherFlags} = adjust_flags(PreThisFlags, PreOtherFlags),
+    {ThisFlags,OtherFlags} = adjust_flags(PreThisFlags,
+                                          PreOtherFlags,
+                                          RejFlgs),
     NewHSData = HSData#hs_data{this_flags = ThisFlags,
 			       other_flags = OtherFlags, 
 			       other_started = false}, 
@@ -336,15 +436,16 @@ handshake_we_started(#hs_data{request_type=ReqType,
 handshake_we_started(OldHsData) when element(1,OldHsData) =:= hs_data ->
     handshake_we_started(convert_old_hsdata(OldHsData)).
 
-convert_old_hsdata({hs_data, KP, ON, TN, S, T, TF, A, OV, OF, OS, FS, FR,
-		    FS_PRE, FS_POST, FG, FA, MFT, MFG, RT}) ->
-    #hs_data{
-       kernel_pid = KP, other_node = ON, this_node = TN, socket = S, timer = T,
-       this_flags = TF, allowed = A, other_version = OV, other_flags = OF,
-       other_started = OS, f_send = FS, f_recv = FR, f_setopts_pre_nodeup = FS_PRE,
-       f_setopts_post_nodeup = FS_POST, f_getll = FG, f_address = FA,
-       mf_tick = MFT, mf_getstat = MFG, request_type = RT}.
+convert_old_hsdata(OldHsData) ->
+    OHSDL = tuple_to_list(OldHsData),
+    NoMissing = tuple_size(#hs_data{}) - tuple_size(OldHsData),
+    true = NoMissing > 0,
+    list_to_tuple(OHSDL ++ lists:duplicate(NoMissing, undefined)).
 
+convert_flags(Flags) when is_integer(Flags) ->
+    Flags;
+convert_flags(_Undefined) ->
+    0.
 
 %% --------------------------------------------------------------
 %% The connection has been established.
@@ -359,15 +460,20 @@ connection(#hs_data{other_node = Node,
     PType = publish_type(HSData#hs_data.other_flags), 
     case FPreNodeup(Socket) of
 	ok -> 
-	    do_setnode(HSData), % Succeeds or exits the process.
+	    DHandle = do_setnode(HSData), % Succeeds or exits the process.
 	    Address = FAddress(Socket,Node),
 	    mark_nodeup(HSData,Address),
 	    case FPostNodeup(Socket) of
 		ok ->
+                    case HSData#hs_data.f_handshake_complete of
+                        undefined -> ok;
+                        HsComplete -> HsComplete(Socket, Node, DHandle)
+                    end,
 		    con_loop({HSData#hs_data.kernel_pid,
 			      Node,
 			      Socket,
 			      PType,
+                              DHandle,
 			      HSData#hs_data.mf_tick,
 			      HSData#hs_data.mf_getstat,
 			      HSData#hs_data.mf_setopts,
@@ -425,18 +531,16 @@ do_setnode(#hs_data{other_node = Node, socket = Socket,
 		   [Node, Port, {publish_type(Flags), 
 				 '(', Flags, ')', 
 				 Version}]),
-	    case (catch 
-		  erlang:setnode(Node, Port, 
-				 {Flags, Version, '', ''})) of
-		{'EXIT', {system_limit, _}} ->
+            try
+                erlang:setnode(Node, Port, {Flags, Version, '', ''})
+            catch
+                error:system_limit ->
 		    error_msg("** Distribution system limit reached, "
 			      "no table space left for node ~w ** ~n",
 			      [Node]),
 		    ?shutdown(Node);
-		{'EXIT', Other} ->
-		    exit(Other);
-		_Else ->
-		    ok
+                error:Other ->
+                    exit({Other, erlang:get_stacktrace()})
 	    end;
 	_ ->
 	    error_msg("** Distribution connection error, "
@@ -468,7 +572,13 @@ mark_nodeup(#hs_data{kernel_pid = Kernel,
 	    ?shutdown(Node)
     end.
 
-con_loop({Kernel, Node, Socket, Type, MFTick, MFGetstat, MFSetOpts, MFGetOpts}=ConData,
+getstat(DHandle, _Socket, undefined) ->
+    erlang:dist_get_stat(DHandle);
+getstat(_DHandle, Socket, MFGetstat) ->
+    MFGetstat(Socket).
+
+con_loop({Kernel, Node, Socket, Type, DHandle, MFTick, MFGetstat,
+          MFSetOpts, MFGetOpts}=ConData,
 	 Tick) ->
     receive
 	{tcp_closed, Socket} ->
@@ -476,7 +586,7 @@ con_loop({Kernel, Node, Socket, Type, MFTick, MFGetstat, MFSetOpts, MFGetOpts}=C
 	{Kernel, disconnect} ->
 	    ?shutdown2(Node, disconnected);
 	{Kernel, aux_tick} ->
-	    case MFGetstat(Socket) of
+	    case getstat(DHandle, Socket, MFGetstat) of
 		{ok, _, _, PendWrite} ->
 		    send_tick(Socket, PendWrite, MFTick);
 		_ ->
@@ -484,7 +594,7 @@ con_loop({Kernel, Node, Socket, Type, MFTick, MFGetstat, MFSetOpts, MFGetOpts}=C
 	    end,
 	    con_loop(ConData, Tick);
 	{Kernel, tick} ->
-	    case send_tick(Socket, Tick, Type, 
+	    case send_tick(DHandle, Socket, Tick, Type, 
 			   MFTick, MFGetstat) of
 		{ok, NewTick} ->
 		    con_loop(ConData, NewTick);
@@ -497,7 +607,7 @@ con_loop({Kernel, Node, Socket, Type, MFTick, MFGetstat, MFSetOpts, MFGetOpts}=C
 		    ?shutdown2(Node, send_net_tick_failed)
 	    end;
 	{From, get_status} ->
-	    case MFGetstat(Socket) of
+	    case getstat(DHandle, Socket, MFGetstat) of
 		{ok, Read, Write, _} ->
 		    From ! {self(), get_status, {ok, Read, Write}},
 		    con_loop(ConData, Tick);
@@ -735,14 +845,14 @@ send_status(#hs_data{socket = Socket, other_node = Node,
 %% we haven't read anything as a hidden node only ticks when it receives 
 %% a TICK !! 
 	
-send_tick(Socket, Tick, Type, MFTick, MFGetstat) ->
+send_tick(DHandle, Socket, Tick, Type, MFTick, MFGetstat) ->
     #tick{tick = T0,
 	  read = Read,
 	  write = Write,
 	  ticked = Ticked} = Tick,
     T = T0 + 1,
     T1 = T rem 4,
-    case MFGetstat(Socket) of
+    case getstat(DHandle, Socket, MFGetstat) of
 	{ok, Read, _, _} when  Ticked =:= T ->
 	    {error, not_responding};
 	{ok, Read, W, Pend} when Type =:= hidden ->
@@ -771,11 +881,10 @@ send_tick(Socket, Tick, Type, MFTick, MFGetstat) ->
 	    Error
     end.
 
-send_tick(Socket, 0, MFTick) ->
-    MFTick(Socket);
-send_tick(_, _Pend, _) ->
-    %% Dont send tick if pending write.
-    ok.
+send_tick(_, Pend, _) when Pend /= false, Pend /= 0 ->
+    ok; %% Dont send tick if pending write.
+send_tick(Socket, _Pend, MFTick) ->
+    MFTick(Socket).
 
 %% ------------------------------------------------------------
 %% Connection setup timeout timer.
diff --git a/lib/kernel/src/erl_boot_server.erl b/lib/kernel/src/erl_boot_server.erl
index ac81cc9689..2a38266579 100644
--- a/lib/kernel/src/erl_boot_server.erl
+++ b/lib/kernel/src/erl_boot_server.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2016. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2017. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -253,9 +253,9 @@ handle_info({udp, U, IP, Port, Data}, S0) ->
 				   "~w is not a valid address ** ~n", [IP]),
 	    {noreply,S0};
 	{true,_,_} ->
-	    case catch string:substr(Data, 1, length(?EBOOT_REQUEST)) of
+	    case catch string:slice(Data, 0, length(?EBOOT_REQUEST)) of
 		?EBOOT_REQUEST ->
-		    Vsn = string:substr(Data, length(?EBOOT_REQUEST)+1, length(Data)),
+		    Vsn = string:slice(Data, length(?EBOOT_REQUEST), length(Data)),
 		    error_logger:error_msg("** Illegal boot server connection attempt: "
 					   "client version is ~s ** ~n", [Vsn]);
 		_ ->
diff --git a/lib/kernel/src/erl_epmd.erl b/lib/kernel/src/erl_epmd.erl
index 7bc9e2ede3..f96bc88913 100644
--- a/lib/kernel/src/erl_epmd.erl
+++ b/lib/kernel/src/erl_epmd.erl
@@ -79,7 +79,13 @@ port_please(Node, EpmdAddr, Timeout) ->
 
 
 port_please1(Node,HostName, Timeout) ->
-  case inet:gethostbyname(HostName, inet, Timeout) of
+  Family = case inet_db:res_option(inet6) of
+             true ->
+               inet6;
+             false ->
+               inet
+           end,
+  case inet:gethostbyname(HostName, Family, Timeout) of
     {ok,{hostent, _Name, _ , _Af, _Size, [EpmdAddr | _]}} ->
       get_port(Node, EpmdAddr, Timeout);
     Else ->
diff --git a/lib/kernel/src/erl_reply.erl b/lib/kernel/src/erl_reply.erl
index e1e046cbb4..e1c4ffe839 100644
--- a/lib/kernel/src/erl_reply.erl
+++ b/lib/kernel/src/erl_reply.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1997-2016. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2017. All Rights Reserved.
 %% 
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -42,7 +42,7 @@ reply(_) ->
 
 %% convert ip number to tuple
 ip_string_to_tuple(Ip) ->
-    [Ip1,Ip2,Ip3,Ip4] = string:tokens(Ip,"."),
+    [Ip1,Ip2,Ip3,Ip4] = string:lexemes(Ip,"."),
     {list_to_integer(Ip1),
      list_to_integer(Ip2),
      list_to_integer(Ip3),
diff --git a/lib/kernel/src/erts_debug.erl b/lib/kernel/src/erts_debug.erl
index 9662f8fa90..3456c8511e 100644
--- a/lib/kernel/src/erts_debug.erl
+++ b/lib/kernel/src/erts_debug.erl
@@ -21,7 +21,7 @@
 
 %% Low-level debugging support. EXPERIMENTAL!
 
--export([size/1,df/1,df/2,df/3,df/4,ic/1]).
+-export([size/1,df/1,df/2,df/3,dis_to_file/2,ic/1]).
 
 %% This module contains the following *experimental* BIFs:
 %%   disassemble/1
@@ -347,55 +347,52 @@ is_term_seen(_, []) -> false.
 -spec df(module()) -> df_ret().
 
 df(Mod) when is_atom(Mod) ->
-    df(lists:concat([Mod, ".dis"]), Mod).
-
--spec df(module(), atom()) -> df_ret();
-        (file:io_device() | file:filename(), module()) -> df_ret().
-
-df(Mod, Func) when is_atom(Mod), is_atom(Func) ->
-    df(lists:concat([Mod, "_", Func, ".dis"]), Mod, Func);
-df(Name, Mod) when is_atom(Mod) ->
     try Mod:module_info(functions) of
 	Fs0 when is_list(Fs0) ->
+	    Name = lists:concat([Mod, ".dis"]),
 	    Fs = [{Mod,Func,Arity} || {Func,Arity} <- Fs0],
 	    dff(Name, Fs)
     catch _:_ -> {undef,Mod}
     end.
 
+-spec df(module(), atom()) -> df_ret().
 
--spec df(module(), atom(), arity()) -> df_ret();
-        (file:io_device() | file:filename(), module(), atom()) -> df_ret().
-
-df(Mod, Func, Arity) when is_atom(Mod), is_atom(Func), is_integer(Arity) ->
-    df(lists:concat([Mod, "_", Func, "_", Arity, ".dis"]), Mod, Func, Arity);
-df(Name, Mod, Func) when is_atom(Mod), is_atom(Func) ->
+df(Mod, Func) when is_atom(Mod), is_atom(Func) ->
     try Mod:module_info(functions) of
 	Fs0 when is_list(Fs0) ->
+	    Name = lists:concat([Mod, "_", Func, ".dis"]),
 	    Fs = [{Mod,Func1,Arity} || {Func1,Arity} <- Fs0, Func1 =:= Func],
 	    dff(Name, Fs)
     catch _:_ -> {undef,Mod}
     end.
 
--spec df(file:io_device() | file:filename(), module(), atom(), arity()) -> df_ret().
-df(Name, Mod, Func, Arity) when is_atom(Mod), is_atom(Func), is_integer(Arity) ->
+-spec df(module(), atom(), arity()) -> df_ret().
+
+df(Mod, Func, Arity) when is_atom(Mod), is_atom(Func) ->
     try Mod:module_info(functions) of
 	Fs0 when is_list(Fs0) ->
+	    Name = lists:concat([Mod, "_", Func, "_", Arity, ".dis"]),
 	    Fs = [{Mod,Func1,Arity1} || {Func1,Arity1} <- Fs0,
 					Func1 =:= Func, Arity1 =:= Arity],
 	    dff(Name, Fs)
     catch _:_ -> {undef,Mod}
     end.
 
-dff(File, Fs) when is_pid(File), is_list(Fs) ->
-    lists:foreach(fun(Mfa) ->
-			  disassemble_function(File, Mfa),
-			  io:nl(File)
-		  end, Fs);
-dff(Name, Fs) when is_list(Name) ->
-    case file:open(Name, [write]) of
+-spec dis_to_file(module(), file:filename()) -> df_ret().
+
+dis_to_file(Mod, Name) when is_atom(Mod) ->
+    try Mod:module_info(functions) of
+	Fs0 when is_list(Fs0) ->
+	    Fs = [{Mod,Func,Arity} || {Func,Arity} <- Fs0],
+	    dff(Name, Fs)
+    catch _:_ -> {undef,Mod}
+    end.
+
+dff(Name, Fs) ->
+    case file:open(Name, [write,raw,delayed_write]) of
 	{ok,F} ->
 	    try
-		dff(F, Fs)
+		dff_1(F, Fs)
 	    after
 		_ = file:close(F)
 	    end;
@@ -403,12 +400,18 @@ dff(Name, Fs) when is_list(Name) ->
 	    {error,{badopen,Reason}}
     end.
 
+dff_1(File, Fs) ->
+    lists:foreach(fun(Mfa) ->
+                          disassemble_function(File, Mfa),
+                          file:write(File, "\n")
+                  end, Fs).
+
 disassemble_function(File, {_,_,_}=MFA) ->
     cont_dis(File, erts_debug:disassemble(MFA), MFA).
 
 cont_dis(_, false, _) -> ok;
 cont_dis(File, {Addr,Str,MFA}, MFA) ->
-    io:put_chars(File, binary_to_list(Str)),
+    ok = file:write(File, Str),
     cont_dis(File, erts_debug:disassemble(Addr), MFA);
 cont_dis(_, {_,_,_}, _) -> ok.
 
diff --git a/lib/kernel/src/file.erl b/lib/kernel/src/file.erl
index 933f2d5f65..d05199897f 100644
--- a/lib/kernel/src/file.erl
+++ b/lib/kernel/src/file.erl
@@ -72,7 +72,7 @@
               io_device/0, name/0, name_all/0, posix/0]).
 
 %%% Includes and defines
--include("file.hrl").
+-include("file_int.hrl").
 
 -define(FILE_IO_SERVER_TABLE, file_io_servers).
 
@@ -454,41 +454,23 @@ raw_write_file_info(Name, #file_info{} = Info) ->
       Reason :: posix() | badarg | system_limit.
 
 open(Item, ModeList) when is_list(ModeList) ->
-    case lists:member(raw, ModeList) of
-	%% Raw file, use ?PRIM_FILE to handle this file
-	true ->
+    case {lists:member(raw, ModeList), lists:member(ram, ModeList)} of
+        {false, false} ->
+            %% File server file
             Args = [file_name(Item) | ModeList],
             case check_args(Args) of
                 ok ->
                     [FileName | _] = Args,
-                    %% We rely on the returned Handle (in {ok, Handle})
-                    %% being a pid() or a #file_descriptor{}
-                    ?PRIM_FILE:open(FileName, ModeList);
+                    call(open, [FileName, ModeList]);
                 Error ->
                     Error
-	    end;
-	false ->
-	    case lists:member(ram, ModeList) of
-		%% RAM file, use ?RAM_FILE to handle this file
-		true ->
-		    case check_args(ModeList) of
-			ok ->
-			    ?RAM_FILE:open(Item, ModeList);
-			Error ->
-			    Error
-		    end;
-		%% File server file
-		false ->
-		    Args = [file_name(Item) | ModeList],
-		    case check_args(Args) of 
-			ok ->
-			    [FileName | _] = Args,
-			    call(open, [FileName, ModeList]);
-			Error ->
-			    Error
-		    end
-	    end
+            end;
+        {true, _Either} ->
+            raw_file_io:open(file_name(Item), ModeList);
+        {false, true} ->
+            ram_file:open(Item, ModeList)
     end;
+
 %% Old obsolete mode specification in atom or 2-tuple format
 open(Item, Mode) ->
     open(Item, mode_list(Mode)).
@@ -1254,15 +1236,18 @@ sendfile(File, _Sock, _Offet, _Bytes, _Opts) when is_pid(File) ->
 sendfile(File, Sock, Offset, Bytes, []) ->
     sendfile(File, Sock, Offset, Bytes, ?MAX_CHUNK_SIZE, [], [], []);
 sendfile(File, Sock, Offset, Bytes, Opts) ->
-    ChunkSize0 = proplists:get_value(chunk_size, Opts, ?MAX_CHUNK_SIZE),
-    ChunkSize = if ChunkSize0 > ?MAX_CHUNK_SIZE ->
-			?MAX_CHUNK_SIZE;
-		   true -> ChunkSize0
-		end,
-    %% Support for headers, trailers and options has been removed because the
-    %% Darwin and BSD API for using it does not play nice with
-    %% non-blocking sockets. See unix_efile.c for more info.
-    sendfile(File, Sock, Offset, Bytes, ChunkSize, [], [], Opts).
+    try proplists:get_value(chunk_size, Opts, ?MAX_CHUNK_SIZE) of
+        ChunkSize0 when is_integer(ChunkSize0) ->
+            ChunkSize = erlang:min(ChunkSize0, ?MAX_CHUNK_SIZE),
+            %% Support for headers, trailers and options has been removed
+            %% because the Darwin and BSD API for using it does not play nice
+            %% with non-blocking sockets. See unix_efile.c for more info.
+            sendfile(File, Sock, Offset, Bytes, ChunkSize, [], [], Opts);
+        _Other ->
+            {error, badarg}
+    catch
+        error:_ -> {error, badarg}
+    end.
 
 %% sendfile/2
 -spec sendfile(Filename, Socket) ->
diff --git a/lib/compiler/src/v3_life.hrl b/lib/kernel/src/file_int.hrl
index 5c76312067..bafc330c04 100644
--- a/lib/compiler/src/v3_life.hrl
+++ b/lib/kernel/src/file_int.hrl
@@ -1,8 +1,8 @@
 %%
 %% %CopyrightBegin%
-%% 
-%% Copyright Ericsson AB 1999-2016. All Rights Reserved.
-%% 
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
 %% You may obtain a copy of the License at
@@ -14,16 +14,20 @@
 %% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 %% See the License for the specific language governing permissions and
 %% limitations under the License.
-%% 
+%%
 %% %CopyrightEnd%
 %%
-%% This record contains variable life-time annotation for a
-%% kernel expression.  Added by v3_life, used by v3_codegen.
 
--type vdb_entry() :: {atom(),non_neg_integer(),non_neg_integer()}.
+%%
+%% Internal definitions for the 'file' module and friends.
+%%
+
+-ifndef(FILE_INTERNAL_HRL_).
+-define(FILE_INTERNAL_HRL_, 1).
+
+-include("file.hrl").
 
--record(l, {ke,					%Kernel expression
-	    i=0 :: non_neg_integer(),           %Op number
-	    vdb=[] :: [vdb_entry()],            %Variable database
-	    a=[] :: [term()]}).                 %Core annotation
+-define(CALL_FD(Fd, Method, Args),
+    apply(Fd#file_descriptor.module, Method, [Fd | Args])).
 
+-endif.
diff --git a/lib/kernel/src/file_io_server.erl b/lib/kernel/src/file_io_server.erl
index deb7b315b1..34d5497a4a 100644
--- a/lib/kernel/src/file_io_server.erl
+++ b/lib/kernel/src/file_io_server.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2000-2015. All Rights Reserved.
+%% Copyright Ericsson AB 2000-2017. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -28,7 +28,8 @@
 
 -record(state, {handle,owner,mref,buf,read_mode,unic}).
 
--define(PRIM_FILE, prim_file).
+-include("file_int.hrl").
+
 -define(READ_SIZE_LIST, 128).
 -define(READ_SIZE_BINARY, (8*1024)).
 
@@ -67,8 +68,9 @@ do_start(Spawn, Owner, FileName, ModeList) ->
 		  erlang:dt_restore_tag(Utag),
 		  %% process_flag(trap_exit, true),
 		  case parse_options(ModeList) of
-		      {ReadMode, UnicodeMode, Opts} ->
-			  case ?PRIM_FILE:open(FileName, Opts) of
+                      {ReadMode, UnicodeMode, Opts0} ->
+                          Opts = maybe_add_read_ahead(ReadMode, Opts0),
+			  case raw_file_io:open(FileName, [raw | Opts]) of
 			      {error, Reason} = Error ->
 				  Self ! {Ref, Error},
 				  exit(Reason);
@@ -157,6 +159,24 @@ valid_enc({utf32,little}) ->
 valid_enc(_Other) ->
     {error,badarg}.
 
+%% Add a small read_ahead buffer if the file is opened for reading
+%% only in list mode and no read_ahead is already given.
+maybe_add_read_ahead(binary, Opts) ->
+    Opts;
+maybe_add_read_ahead(list, Opts) ->
+    P = fun(read_ahead) -> true;
+           ({read_ahead,_}) -> true;
+           (append) -> true;
+           (exclusive) -> true;
+           (write) -> true;
+           (_) -> false
+        end,
+    case lists:any(P, Opts) of
+        false ->
+            [{read_ahead, 4096}|Opts];
+        true ->
+            Opts
+    end.
 
 server_loop(#state{mref = Mref} = State) ->
     receive
@@ -205,7 +225,7 @@ io_reply(From, ReplyAs, Reply) ->
 
 file_request({advise,Offset,Length,Advise},
          #state{handle=Handle}=State) ->
-    case ?PRIM_FILE:advise(Handle, Offset, Length, Advise) of
+    case ?CALL_FD(Handle, advise, [Offset, Length, Advise]) of
     {error,Reason}=Reply ->
         {stop,Reason,Reply,State};
     Reply ->
@@ -213,7 +233,7 @@ file_request({advise,Offset,Length,Advise},
     end;
 file_request({allocate, Offset, Length},
          #state{handle = Handle} = State) ->
-    Reply = ?PRIM_FILE:allocate(Handle, Offset, Length),
+    Reply = ?CALL_FD(Handle, allocate, [Offset, Length]),
     {reply, Reply, State};
 file_request({pread,At,Sz}, State)
   when At =:= cur;
@@ -256,7 +276,7 @@ file_request({pwrite,At,Data},
     end;
 file_request(datasync,
 	     #state{handle=Handle}=State) ->
-    case ?PRIM_FILE:datasync(Handle) of
+    case ?CALL_FD(Handle, datasync, []) of
 	{error,Reason}=Reply ->
 	    {stop,Reason,Reply,State};
 	Reply ->
@@ -264,7 +284,7 @@ file_request(datasync,
     end;
 file_request(sync, 
 	     #state{handle=Handle}=State) ->
-    case ?PRIM_FILE:sync(Handle) of
+    case ?CALL_FD(Handle, sync, []) of
 	{error,Reason}=Reply ->
 	    {stop,Reason,Reply,State};
 	Reply ->
@@ -272,7 +292,7 @@ file_request(sync,
     end;
 file_request(close, 
 	     #state{handle=Handle}=State) ->
-    case ?PRIM_FILE:close(Handle) of
+    case ?CALL_FD(Handle, close, []) of
 	{error,Reason}=Reply ->
 	    {stop,Reason,Reply,State#state{buf= <<>>}};
 	Reply ->
@@ -288,7 +308,7 @@ file_request({position,At},
     end;
 file_request(truncate, 
 	     #state{handle=Handle}=State) ->
-    case ?PRIM_FILE:truncate(Handle) of
+    case ?CALL_FD(Handle, truncate, []) of
 	{error,Reason}=Reply ->
 	    {stop,Reason,Reply,State#state{buf= <<>>}};
 	Reply ->
@@ -398,7 +418,7 @@ io_request_loop([Request|Tail],
 %%
 put_chars(Chars, latin1, #state{handle=Handle, unic=latin1}=State) ->
     NewState = State#state{buf = <<>>},
-    case ?PRIM_FILE:write(Handle, Chars) of
+    case ?CALL_FD(Handle, write, [Chars]) of
 	{error,Reason}=Reply ->
 	    {stop,Reason,Reply,NewState};
 	Reply ->
@@ -408,7 +428,7 @@ put_chars(Chars, InEncoding, #state{handle=Handle, unic=OutEncoding}=State) ->
     NewState = State#state{buf = <<>>},
     case unicode:characters_to_binary(Chars,InEncoding,OutEncoding) of
 	Bin when is_binary(Bin) ->
-	    case ?PRIM_FILE:write(Handle, Bin) of
+	    case ?CALL_FD(Handle, write, [Bin]) of
 		{error,Reason}=Reply ->
 		    {stop,Reason,Reply,NewState};
 		Reply ->
@@ -422,7 +442,7 @@ put_chars(Chars, InEncoding, #state{handle=Handle, unic=OutEncoding}=State) ->
 
 get_line(S, {<<>>, Cont}, OutEnc,
 	 #state{handle=Handle, read_mode=Mode, unic=InEnc}=State) ->
-    case ?PRIM_FILE:read(Handle, read_size(Mode)) of
+    case ?CALL_FD(Handle, read, [read_size(Mode)]) of
 	{ok,Bin} ->
 	    get_line(S, convert_enc([Cont, Bin], InEnc, OutEnc), OutEnc, State);
 	eof ->
@@ -472,7 +492,7 @@ get_chars(N, OutEnc,#state{handle=Handle,buf=Buf,read_mode=ReadMode,unic=latin1}
     BufSize = byte_size(Buf),
     NeedSize = N-BufSize,
     Size = erlang:max(NeedSize, ?READ_SIZE_BINARY),
-    case ?PRIM_FILE:read(Handle, Size) of
+    case ?CALL_FD(Handle, read, [Size]) of
 	{ok, B} ->
 	    if BufSize+byte_size(B) < N ->
 		    std_reply(cat(Buf, B, ReadMode,latin1,OutEnc), State);
@@ -504,7 +524,7 @@ get_chars(N, OutEnc,#state{handle=Handle,buf=Buf,read_mode=ReadMode,unic=InEncod
 		%% Need more, Try to read 4*needed in bytes...
 		NeedSize = (N - BufCount) * 4,
 		Size = erlang:max(NeedSize, ?READ_SIZE_BINARY),
-		case ?PRIM_FILE:read(Handle, Size) of
+		case ?CALL_FD(Handle, read, [Size]) of
 		    {ok, B} ->
 			NewBuf = list_to_binary([Buf,B]),
 			{NewCount,NewSplit} = count_and_find(NewBuf,N,InEncoding),
@@ -544,7 +564,7 @@ get_chars(Mod, Func, XtraArg, OutEnc, #state{buf=Buf}=State) ->
 
 get_chars_empty(Mod, Func, XtraArg, S, latin1,
 		#state{handle=Handle,read_mode=ReadMode, unic=latin1}=State) ->
-    case ?PRIM_FILE:read(Handle, read_size(ReadMode)) of
+    case ?CALL_FD(Handle, read, [read_size(ReadMode)]) of
 	{ok,Bin} ->
 	    get_chars_apply(Mod, Func, XtraArg, S, latin1, State, Bin);
 	eof ->
@@ -554,7 +574,7 @@ get_chars_empty(Mod, Func, XtraArg, S, latin1,
     end;
 get_chars_empty(Mod, Func, XtraArg, S, OutEnc,
 		#state{handle=Handle,read_mode=ReadMode}=State) ->
-    case ?PRIM_FILE:read(Handle, read_size(ReadMode)) of
+    case ?CALL_FD(Handle, read, [read_size(ReadMode)]) of
 	{ok,Bin} ->
 	    get_chars_apply(Mod, Func, XtraArg, S, OutEnc, State, Bin);
 	eof ->
@@ -564,7 +584,7 @@ get_chars_empty(Mod, Func, XtraArg, S, OutEnc,
     end.
 get_chars_notempty(Mod, Func, XtraArg, S, OutEnc,
 		   #state{handle=Handle,read_mode=ReadMode,buf = B}=State) ->
-    case ?PRIM_FILE:read(Handle, read_size(ReadMode)) of
+    case ?CALL_FD(Handle, read, [read_size(ReadMode)]) of
 	{ok,Bin} ->
 	    get_chars_apply(Mod, Func, XtraArg, S, OutEnc, State, list_to_binary([B,Bin]));
 	eof ->
@@ -918,13 +938,10 @@ cbv({utf32,little},_) ->
 %% Compensates ?PRIM_FILE:position/2 for the number of bytes 
 %% we have buffered
 position(Handle, At, Buf) ->
-    ?PRIM_FILE:position(
-       Handle,
-       case At of
-	   cur ->
-	       {cur, -byte_size(Buf)};
-	   {cur, Offs} ->
-	       {cur, Offs-byte_size(Buf)};
-	   _ ->
-	       At
-       end).
+    SeekTo =
+        case At of
+            {cur, Offs} -> {cur, Offs-byte_size(Buf)};
+            cur -> {cur, -byte_size(Buf)};
+            _ -> At
+        end,
+    ?CALL_FD(Handle, position, [SeekTo]).
diff --git a/lib/kernel/src/file_server.erl b/lib/kernel/src/file_server.erl
index 6e8f64d932..ecc1ffbdd6 100644
--- a/lib/kernel/src/file_server.erl
+++ b/lib/kernel/src/file_server.erl
@@ -63,7 +63,7 @@ stop() ->
 %%% Callback functions from gen_server
 %%%----------------------------------------------------------------------
 
--type state() :: port().	% Internal type
+-type state() :: term().	% Internal type
 
 %%----------------------------------------------------------------------
 %% Func: init/1
@@ -77,14 +77,8 @@ stop() ->
 
 init([]) ->
     process_flag(trap_exit, true),
-    case ?PRIM_FILE:start() of
-	{ok, Handle} ->
-	    ?FILE_IO_SERVER_TABLE =
-                ets:new(?FILE_IO_SERVER_TABLE, [named_table]),
-	    {ok, Handle};
-	{error, Reason} ->
-	    {stop, Reason}
-    end.
+    ?FILE_IO_SERVER_TABLE =  ets:new(?FILE_IO_SERVER_TABLE, [named_table]),
+    {ok, undefined}.
 
 %%----------------------------------------------------------------------
 %% Func: handle_call/3
@@ -101,7 +95,7 @@ init([]) ->
 	{'reply', 'eof' | 'ok' | {'error', term()} | {'ok', term()}, state()} |
 	{'stop', 'normal', 'stopped', state()}.
 
-handle_call({open, Name, ModeList}, {Pid, _Tag} = _From, Handle)
+handle_call({open, Name, ModeList}, {Pid, _Tag} = _From, State)
   when is_list(ModeList) ->
     Child = ?FILE_IO_SERVER:start_link(Pid, Name, ModeList),
     case Child of
@@ -110,78 +104,78 @@ handle_call({open, Name, ModeList}, {Pid, _Tag} = _From, Handle)
 	_ ->
 	    ok
     end,
-    {reply, Child, Handle};
+    {reply, Child, State};
 
-handle_call({open, _Name, _Mode}, _From, Handle) ->
-    {reply, {error, einval}, Handle};
+handle_call({open, _Name, _Mode}, _From, State) ->
+    {reply, {error, einval}, State};
 
-handle_call({read_file, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:read_file(Name), Handle};
+handle_call({read_file, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:read_file(Name), State};
 
-handle_call({write_file, Name, Bin}, _From, Handle) ->
-    {reply, ?PRIM_FILE:write_file(Name, Bin), Handle};
+handle_call({write_file, Name, Bin}, _From, State) ->
+    {reply, ?PRIM_FILE:write_file(Name, Bin), State};
 
-handle_call({set_cwd, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:set_cwd(Handle, Name), Handle};
+handle_call({set_cwd, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:set_cwd(Name), State};
 
-handle_call({delete, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:delete(Handle, Name), Handle};
+handle_call({delete, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:delete(Name), State};
 
-handle_call({rename, Fr, To}, _From, Handle) ->
-    {reply, ?PRIM_FILE:rename(Handle, Fr, To), Handle};
+handle_call({rename, Fr, To}, _From, State) ->
+    {reply, ?PRIM_FILE:rename(Fr, To), State};
 
-handle_call({make_dir, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:make_dir(Handle, Name), Handle};
+handle_call({make_dir, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:make_dir(Name), State};
 
-handle_call({del_dir, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:del_dir(Handle, Name), Handle};
+handle_call({del_dir, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:del_dir(Name), State};
 
-handle_call({list_dir, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:list_dir(Handle, Name), Handle};
-handle_call({list_dir_all, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:list_dir_all(Handle, Name), Handle};
+handle_call({list_dir, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:list_dir(Name), State};
+handle_call({list_dir_all, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:list_dir_all(Name), State};
 
-handle_call(get_cwd, _From, Handle) ->
-    {reply, ?PRIM_FILE:get_cwd(Handle), Handle};
-handle_call({get_cwd}, _From, Handle) ->
-    {reply, ?PRIM_FILE:get_cwd(Handle), Handle};
-handle_call({get_cwd, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:get_cwd(Handle, Name), Handle};
+handle_call(get_cwd, _From, State) ->
+    {reply, ?PRIM_FILE:get_cwd(), State};
+handle_call({get_cwd}, _From, State) ->
+    {reply, ?PRIM_FILE:get_cwd(), State};
+handle_call({get_cwd, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:get_cwd(Name), State};
 
-handle_call({read_file_info, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:read_file_info(Handle, Name), Handle};
+handle_call({read_file_info, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:read_file_info(Name), State};
 
-handle_call({read_file_info, Name, Opts}, _From, Handle) ->
-    {reply, ?PRIM_FILE:read_file_info(Handle, Name, Opts), Handle};
+handle_call({read_file_info, Name, Opts}, _From, State) ->
+    {reply, ?PRIM_FILE:read_file_info(Name, Opts), State};
 
-handle_call({altname, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:altname(Handle, Name), Handle};
+handle_call({altname, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:altname(Name), State};
 
-handle_call({write_file_info, Name, Info}, _From, Handle) ->
-    {reply, ?PRIM_FILE:write_file_info(Handle, Name, Info), Handle};
+handle_call({write_file_info, Name, Info}, _From, State) ->
+    {reply, ?PRIM_FILE:write_file_info(Name, Info), State};
 
-handle_call({write_file_info, Name, Info, Opts}, _From, Handle) ->
-    {reply, ?PRIM_FILE:write_file_info(Handle, Name, Info, Opts), Handle};
+handle_call({write_file_info, Name, Info, Opts}, _From, State) ->
+    {reply, ?PRIM_FILE:write_file_info(Name, Info, Opts), State};
 
-handle_call({read_link_info, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:read_link_info(Handle, Name), Handle};
+handle_call({read_link_info, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:read_link_info(Name), State};
 
-handle_call({read_link_info, Name, Opts}, _From, Handle) ->
-    {reply, ?PRIM_FILE:read_link_info(Handle, Name, Opts), Handle};
+handle_call({read_link_info, Name, Opts}, _From, State) ->
+    {reply, ?PRIM_FILE:read_link_info(Name, Opts), State};
 
-handle_call({read_link, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:read_link(Handle, Name), Handle};
-handle_call({read_link_all, Name}, _From, Handle) ->
-    {reply, ?PRIM_FILE:read_link_all(Handle, Name), Handle};
+handle_call({read_link, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:read_link(Name), State};
+handle_call({read_link_all, Name}, _From, State) ->
+    {reply, ?PRIM_FILE:read_link_all(Name), State};
 
-handle_call({make_link, Old, New}, _From, Handle) ->
-    {reply, ?PRIM_FILE:make_link(Handle, Old, New), Handle};
+handle_call({make_link, Old, New}, _From, State) ->
+    {reply, ?PRIM_FILE:make_link(Old, New), State};
 
-handle_call({make_symlink, Old, New}, _From, Handle) ->
-    {reply, ?PRIM_FILE:make_symlink(Handle, Old, New), Handle};
+handle_call({make_symlink, Old, New}, _From, State) ->
+    {reply, ?PRIM_FILE:make_symlink(Old, New), State};
 
 handle_call({copy, SourceName, SourceOpts, DestName, DestOpts, Length},
-	    _From, Handle) ->
+	    _From, State) ->
     Reply = 
 	case ?PRIM_FILE:open(SourceName, [read, binary | SourceOpts]) of
 	    {ok, Source} ->
@@ -201,14 +195,14 @@ handle_call({copy, SourceName, SourceOpts, DestName, DestOpts, Length},
 	    {error, _} = Error ->
 		Error
 	end,
-    {reply, Reply, Handle};
+    {reply, Reply, State};
 
-handle_call(stop, _From, Handle) ->
-    {stop, normal, stopped, Handle};
+handle_call(stop, _From, State) ->
+    {stop, normal, stopped, State};
 
-handle_call(Request, From, Handle) ->
+handle_call(Request, From, State) ->
     error_logger:error_msg("handle_call(~tp, ~tp, _)", [Request, From]),
-    {noreply, Handle}.
+    {noreply, State}.
 
 %%----------------------------------------------------------------------
 %% Func: handle_cast/2
@@ -233,14 +227,9 @@ handle_cast(Msg, State) ->
 -spec handle_info(term(), state()) ->
         {'noreply', state()} | {'stop', 'normal', state()}.
 
-handle_info({'EXIT', Pid, _Reason}, Handle) when is_pid(Pid) ->
+handle_info({'EXIT', Pid, _Reason}, State) when is_pid(Pid) ->
     ets:delete(?FILE_IO_SERVER_TABLE, Pid),
-    {noreply, Handle};
-
-handle_info({'EXIT', Handle, _Reason}, Handle) ->
-    error_logger:error_msg("Port controlling ~w terminated in ~w",
-			   [?FILE_SERVER, ?MODULE]),
-    {stop, normal, Handle};
+    {noreply, State};
 
 handle_info(Info, State) ->
     error_logger:error_msg("handle_Info(~tp, _)", [Info]),
@@ -254,8 +243,8 @@ handle_info(Info, State) ->
 
 -spec terminate(term(), state()) -> 'ok'.
 
-terminate(_Reason, Handle) ->
-    ?PRIM_FILE:stop(Handle).
+terminate(_Reason, _State) ->
+    ok.
 
 %%----------------------------------------------------------------------
 %% Func: code_change/3
diff --git a/lib/kernel/src/group.erl b/lib/kernel/src/group.erl
index bf785959ff..e1198d2587 100644
--- a/lib/kernel/src/group.erl
+++ b/lib/kernel/src/group.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2017. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2016. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -261,11 +261,11 @@ io_request({put_chars,latin1,M,F,As}, Drv, From, Buf) ->
     end;
 
 io_request({get_chars,Encoding,Prompt,N}, Drv, _From, Buf) ->
-    get_chars(Prompt, io_lib, collect_chars, N, Drv, Buf, Encoding);
+    get_chars_n(Prompt, io_lib, collect_chars, N, Drv, Buf, Encoding);
 io_request({get_line,Encoding,Prompt}, Drv, _From, Buf) ->
-    get_chars(Prompt, io_lib, collect_line, [], Drv, Buf, Encoding);
+    get_chars_line(Prompt, io_lib, collect_line, [], Drv, Buf, Encoding);
 io_request({get_until,Encoding, Prompt,M,F,As}, Drv, _From, Buf) ->
-    get_chars(Prompt, io_lib, get_until, {M,F,As}, Drv, Buf, Encoding);
+    get_chars_line(Prompt, io_lib, get_until, {M,F,As}, Drv, Buf, Encoding);
 io_request({get_password,_Encoding},Drv,_From,Buf) ->
     get_password_chars(Drv, Buf);
 io_request({setopts,Opts}, Drv, _From, Buf) when is_list(Opts) ->
@@ -434,7 +434,7 @@ getopts(Drv,Buf) ->
     {ok,[Exp,Echo,Bin,Uni],Buf}.
     
 
-%% get_chars(Prompt, Module, Function, XtraArgument, Drv, Buffer)
+%% get_chars_*(Prompt, Module, Function, XtraArgument, Drv, Buffer)
 %%  Gets characters from the input Drv until as the applied function
 %%  returns {stop,Result,Rest}. Does not block output until input has been
 %%  received.
@@ -452,12 +452,21 @@ get_password_chars(Drv,Buf) ->
 	    {exit, terminated}
     end.
 
-get_chars(Prompt, M, F, Xa, Drv, Buf, Encoding) ->
+get_chars_n(Prompt, M, F, Xa, Drv, Buf, Encoding) ->
+    Pbs = prompt_bytes(Prompt, Encoding),
+    case get(echo) of
+        true ->
+            get_chars_loop(Pbs, M, F, Xa, Drv, Buf, start, Encoding);
+        false ->
+            get_chars_n_loop(Pbs, M, F, Xa, Drv, Buf, start, Encoding)
+    end.
+
+get_chars_line(Prompt, M, F, Xa, Drv, Buf, Encoding) ->
     Pbs = prompt_bytes(Prompt, Encoding),
     get_chars_loop(Pbs, M, F, Xa, Drv, Buf, start, Encoding).
 
 get_chars_loop(Pbs, M, F, Xa, Drv, Buf0, State, Encoding) ->
-    Result = case get(echo) of 
+    Result = case get(echo) of
 		 true ->
 		     get_line(Buf0, Pbs, Drv, Encoding);
 		 false ->
@@ -466,8 +475,8 @@ get_chars_loop(Pbs, M, F, Xa, Drv, Buf0, State, Encoding) ->
 		     get_line_echo_off(Buf0, Pbs, Drv)
 	     end,
     case Result of
-	{done,Line,Buf1} ->
-	    get_chars_apply(Pbs, M, F, Xa, Drv, Buf1, State, Line, Encoding);
+	{done,Line,Buf} ->
+            get_chars_apply(Pbs, M, F, Xa, Drv, Buf, State, Line, Encoding);
 	interrupted ->
 	    {error,{error,interrupted},[]};
 	terminated ->
@@ -476,12 +485,29 @@ get_chars_loop(Pbs, M, F, Xa, Drv, Buf0, State, Encoding) ->
 
 get_chars_apply(Pbs, M, F, Xa, Drv, Buf, State0, Line, Encoding) ->
     case catch M:F(State0, cast(Line,get(read_mode), Encoding), Encoding, Xa) of
-	{stop,Result,Rest} ->
-	    {ok,Result,append(Rest, Buf, Encoding)};
-	{'EXIT',_} ->
-	    {error,{error,err_func(M, F, Xa)},[]};
-	State1 ->
-	    get_chars_loop(Pbs, M, F, Xa, Drv, Buf, State1, Encoding)
+        {stop,Result,Rest} ->
+            {ok,Result,append(Rest, Buf, Encoding)};
+        {'EXIT',_} ->
+            {error,{error,err_func(M, F, Xa)},[]};
+        State1 ->
+            get_chars_loop(Pbs, M, F, Xa, Drv, Buf, State1, Encoding)
+    end.
+
+get_chars_n_loop(Pbs, M, F, Xa, Drv, Buf0, State, Encoding) ->
+    try M:F(State, cast(Buf0, get(read_mode), Encoding), Encoding, Xa) of
+        {stop,Result,Rest} ->
+            {ok, Result, Rest};
+        State1 ->
+            case get_chars_echo_off(Pbs, Drv) of
+                interrupted ->
+                    {error,{error,interrupted},[]};
+                terminated ->
+                    {exit,terminated};
+                Buf ->
+                    get_chars_n_loop(Pbs, M, F, Xa, Drv, Buf, State1, Encoding)
+            end
+    catch _:_ ->
+            {error,{error,err_func(M, F, Xa)},[]}
     end.
 
 %% Convert error code to make it look as before
@@ -684,6 +710,29 @@ get_line_echo_off1({Chars,[]}, Drv) ->
 get_line_echo_off1({Chars,Rest}, _Drv) ->
     {done,lists:reverse(Chars),case Rest of done -> []; _ -> Rest end}.
 
+get_chars_echo_off(Pbs, Drv) ->
+    send_drv_reqs(Drv, [{put_chars, unicode,Pbs}]),
+    get_chars_echo_off1(Drv).
+
+get_chars_echo_off1(Drv) ->
+    receive
+        {Drv, {data, Cs}} ->
+            Cs;
+	{Drv, eof} ->
+            eof;
+	{io_request,From,ReplyAs,Req} when is_pid(From) ->
+	    io_request(Req, From, ReplyAs, Drv, []),
+	    get_chars_echo_off1(Drv);
+        {reply,{{From,ReplyAs},Reply}} when From =/= undefined ->
+            %% We take care of replies from puts here as well
+            io_reply(From, ReplyAs, Reply),
+            get_chars_echo_off1(Drv);
+	{'EXIT',Drv,interrupt} ->
+	    interrupted;
+	{'EXIT',Drv,_} ->
+	    terminated
+    end.
+
 %% We support line editing for the ICANON mode except the following
 %% line editing characters, which already has another meaning in
 %% echo-on mode (See Advanced Programming in the Unix Environment, 2nd ed,
@@ -793,9 +842,9 @@ search_up_stack(Stack, Substr) ->
     case up_stack(Stack) of
 	{none,NewStack} -> {none,NewStack};
 	{L, NewStack} ->
-	    case string:str(L, Substr) of
-		0 -> search_up_stack(NewStack, Substr);
-		_ -> {string:strip(L,right,$\n), NewStack}
+            case string:find(L, Substr) of
+                nomatch -> search_up_stack(NewStack, Substr);
+                _ -> {string:trim(L, trailing, "$\n"), NewStack}
 	    end
     end.
 
@@ -803,9 +852,9 @@ search_down_stack(Stack, Substr) ->
     case down_stack(Stack) of
 	{none,NewStack} -> {none,NewStack};
 	{L, NewStack} ->
-	    case string:str(L, Substr) of
-		0 -> search_down_stack(NewStack, Substr);
-		_ -> {string:strip(L,right,$\n), NewStack}
+	    case string:find(L, Substr) of
+		nomatch -> search_down_stack(NewStack, Substr);
+		_ -> {string:trim(L, trailing, "$\n"), NewStack}
 	    end
     end.
 
diff --git a/lib/kernel/src/inet_config.erl b/lib/kernel/src/inet_config.erl
index 4bbc520449..9f76360b8b 100644
--- a/lib/kernel/src/inet_config.erl
+++ b/lib/kernel/src/inet_config.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1997-2016. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2017. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -369,7 +369,7 @@ win32_load1(Reg,Type,HFileKey) ->
     end.
 
 win32_split_line(Line,nt) -> inet_parse:split_line(Line);
-win32_split_line(Line,windows) -> string:tokens(Line, ",").
+win32_split_line(Line,windows) -> string:lexemes(Line, ",").
 
 win32_get_strings(Reg, Names) ->
     win32_get_strings(Reg, Names, []).
diff --git a/lib/kernel/src/inet_dns.erl b/lib/kernel/src/inet_dns.erl
index d5f982cc51..f1f58bc872 100644
--- a/lib/kernel/src/inet_dns.erl
+++ b/lib/kernel/src/inet_dns.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1997-2016. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2017. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -29,7 +29,7 @@
 
 -export([decode/1, encode/1]).
 
--import(lists, [reverse/1, reverse/2, nthtail/2]).
+-import(lists, [reverse/1]).
 
 -include("inet_int.hrl").
 -include("inet_dns.hrl").
@@ -473,7 +473,7 @@ decode_data(<<Order:16,Preference:16,Data0/binary>>, _, ?S_NAPTR, Buffer) ->
     {Data2,Services} = decode_string(Data1),
     {Data,Regexp} = decode_characters(Data2, utf8),
     Replacement = decode_domain(Data, Buffer),
-    {Order,Preference,string:to_lower(Flags),string:to_lower(Services),
+    {Order,Preference,string:lowercase(Flags),string:lowercase(Services),
      Regexp,Replacement};
 %% ?S_OPT falls through to default
 decode_data(Data, _, ?S_TXT, _) ->
diff --git a/lib/kernel/src/inet_int.hrl b/lib/kernel/src/inet_int.hrl
index bc5b67f7bf..357e27826c 100644
--- a/lib/kernel/src/inet_int.hrl
+++ b/lib/kernel/src/inet_int.hrl
@@ -100,6 +100,8 @@
 -define(TCP_REQ_RECV,           42).
 -define(TCP_REQ_UNRECV,         43).
 -define(TCP_REQ_SHUTDOWN,       44).
+-define(TCP_REQ_SENDFILE,       45).
+
 %% UDP and SCTP requests
 -define(PACKET_REQ_RECV,        60).
 %%-define(SCTP_REQ_LISTEN,        61). MERGED
@@ -319,6 +321,12 @@
 	[((X) bsr 24) band 16#ff, ((X) bsr 16) band 16#ff,
 	 ((X) bsr 8) band 16#ff, (X) band 16#ff]).
 
+-define(int64(X),
+	[((X) bsr 56) band 16#ff, ((X) bsr 48) band 16#ff,
+	 ((X) bsr 40) band 16#ff, ((X) bsr 32) band 16#ff,
+	 ((X) bsr 24) band 16#ff, ((X) bsr 16) band 16#ff,
+	 ((X) bsr 8) band 16#ff, (X) band 16#ff]).
+
 -define(intAID(X), % For SCTP AssocID
         ?int32(X)).
 
diff --git a/lib/kernel/src/inet_parse.erl b/lib/kernel/src/inet_parse.erl
index 29804dc50b..e9685c6554 100644
--- a/lib/kernel/src/inet_parse.erl
+++ b/lib/kernel/src/inet_parse.erl
@@ -95,7 +95,7 @@ hosts(Fname,File) ->
 		 %% interface with a %if suffix. These kind of
 		 %% addresses maybe need to be gracefully handled
 		 %% throughout inet* and inet_drv.
-		 case string:tokens(Address, "%") of
+		 case string:lexemes(Address, "%") of
 		     [Addr,_] ->
 			 {ok,_} = address(Addr),
 			 skip;
@@ -407,7 +407,7 @@ is_dom1([C | Cs]) when C >= $a, C =< $z -> is_dom_ldh(Cs);
 is_dom1([C | Cs]) when C >= $A, C =< $Z -> is_dom_ldh(Cs);
 is_dom1([C | Cs]) when C >= $0, C =< $9 -> 
     case is_dom_ldh(Cs) of
-	true  -> is_dom2(string:tokens([C | Cs],"."));
+	true  -> is_dom2(string:lexemes([C | Cs],"."));
 	false -> false
     end;
 is_dom1(_) -> false.
diff --git a/lib/kernel/src/inet_res.erl b/lib/kernel/src/inet_res.erl
index 90e49ddfdf..49aa5f8bda 100644
--- a/lib/kernel/src/inet_res.erl
+++ b/lib/kernel/src/inet_res.erl
@@ -859,15 +859,17 @@ query_ns(S0, Id, Buffer, IP, Port, Timer, Retry, I,
 		{ok,S} ->
 		    Timeout =
 			inet:timeout( (Tm * (1 bsl I)) div Retry, Timer),
-		    {S,
 		     case query_udp(
 			    S, Id, Buffer, IP, Port, Timeout, Verbose) of
 			 {ok,#dns_rec{header=H}} when H#dns_header.tc ->
 			     TcpTimeout = inet:timeout(Tm*5, Timer),
-			     query_tcp(
-			       TcpTimeout, Id, Buffer, IP, Port, Verbose);
-			 Reply -> Reply
-		     end};
+			     {S, query_tcp(
+			       TcpTimeout, Id, Buffer, IP, Port, Verbose)};
+			{error, econnrefused} = Err ->
+                            ok = udp_close(S),
+	                    {#sock{}, Err};
+			Reply -> {S, Reply}
+		     end;
 		Error ->
 		    {S0,Error}
 	    end
diff --git a/lib/kernel/src/kernel.app.src b/lib/kernel/src/kernel.app.src
index 2a88cc7e26..82a3571da9 100644
--- a/lib/kernel/src/kernel.app.src
+++ b/lib/kernel/src/kernel.app.src
@@ -57,6 +57,7 @@
 	     inet_tcp_dist,
 	     kernel,
 	     kernel_config,
+	     kernel_refc,
 	     local_tcp,
 	     local_udp,
 	     net,
@@ -88,6 +89,13 @@
              inet_udp,
 	     inet_sctp,
              pg2,
+             raw_file_io,
+             raw_file_io_compressed,
+             raw_file_io_deflate,
+             raw_file_io_delayed,
+             raw_file_io_inflate,
+             raw_file_io_list,
+             raw_file_io_raw,
 	     seq_trace,
 	     standard_error,
 	     wrap_log_reader]},
@@ -107,6 +115,7 @@
 		heart,
 		init,
 		kernel_config,
+		kernel_refc,
 		kernel_sup,
 		net_kernel,
 		net_sup,
@@ -120,6 +129,6 @@
   {applications, []},
   {env, [{error_logger, tty}]},
   {mod, {kernel, []}},
-  {runtime_dependencies, ["erts-9.1", "stdlib-3.4", "sasl-3.0"]}
+  {runtime_dependencies, ["erts-10.0", "stdlib-3.5", "sasl-3.0"]}
  ]
 }.
diff --git a/lib/kernel/src/kernel.erl b/lib/kernel/src/kernel.erl
index cba57088ec..0382764b39 100644
--- a/lib/kernel/src/kernel.erl
+++ b/lib/kernel/src/kernel.erl
@@ -111,6 +111,13 @@ init([]) ->
                type => worker,
                modules => [kernel_config]},
 
+    RefC = #{id => kernel_refc,
+             start => {kernel_refc, start_link, []},
+             restart => permanent,
+             shutdown => 2000,
+             type => worker,
+             modules => [kernel_refc]},
+
     Code = #{id => code_server,
              start => {code, start_link, []},
              restart => permanent,
@@ -148,7 +155,7 @@ init([]) ->
 
     case init:get_argument(mode) of
         {ok, [["minimal"]]} ->
-            {ok, {SupFlags, [Code, File, StdError, User, Config, SafeSup]}};
+            {ok, {SupFlags, [Code, File, StdError, User, Config, RefC, SafeSup]}};
         _ ->
             Rpc = #{id => rex,
                     start => {rpc, start_link, []},
@@ -199,7 +206,7 @@ init([]) ->
             {ok, {SupFlags,
                   [Code, Rpc, Global, InetDb | DistAC] ++
                   [NetSup, GlGroup, File, SigSrv,
-                   StdError, User, Config, SafeSup] ++ Timer}}
+                   StdError, User, Config, RefC, SafeSup] ++ Timer}}
     end;
 init(safe) ->
     SupFlags = #{strategy => one_for_one,
diff --git a/lib/kernel/src/kernel_refc.erl b/lib/kernel/src/kernel_refc.erl
new file mode 100644
index 0000000000..05076dc885
--- /dev/null
+++ b/lib/kernel/src/kernel_refc.erl
@@ -0,0 +1,139 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(kernel_refc).
+
+-behaviour(gen_server).
+
+%% External exports
+-export([start_link/0, scheduler_wall_time/1]).
+%% Internal exports
+-export([init/1, handle_info/2, terminate/2]).
+-export([handle_call/3, handle_cast/2, code_change/3]).
+
+%%%-----------------------------------------------------------------
+%%% This module implements a process that handles reference counters for
+%%% various erts or other kernel resources which needs reference counting.
+%%%
+%%% Should not be documented nor used directly by user applications.
+%%%-----------------------------------------------------------------
+start_link() ->
+    gen_server:start_link({local,kernel_refc}, kernel_refc, [], []).
+
+-spec scheduler_wall_time(boolean()) -> boolean().
+scheduler_wall_time(Bool) ->
+    gen_server:call(kernel_refc, {scheduler_wall_time, self(), Bool}, infinity).
+
+%%-----------------------------------------------------------------
+%% Callback functions from gen_server
+%%-----------------------------------------------------------------
+
+-spec init([]) -> {'ok', map()} | {'stop', term()}.
+
+init([]) ->
+    resource(scheduler_wall_time, false),
+    {ok, #{scheduler_wall_time=>#{}}}.
+
+-spec handle_call(term(), term(), State) -> {'reply', term(), State}.
+handle_call({What, Who, false}, _From, State) ->
+    {Reply, Cnt} = do_stop(What, maps:get(What, State), Who),
+    {reply, Reply, State#{What:=Cnt}};
+handle_call({What, Who, true}, _From, State) ->
+    {Reply, Cnt} = do_start(What, maps:get(What, State), Who),
+    {reply, Reply, State#{What:=Cnt}};
+handle_call(_, _From, State) ->
+    {reply, badarg, State}.
+
+-spec handle_cast(term(), State) -> {'noreply', State}.
+handle_cast(_, State) ->
+    {noreply, State}.
+
+-spec handle_info(term(), State) -> {'noreply', State}.
+handle_info({'DOWN', _Ref, process, Pid, _}, State) ->
+    Cleanup = fun(Resource, Cnts) ->
+                      cleanup(Resource, Cnts, Pid)
+              end,
+    {noreply, maps:map(Cleanup, State)};
+handle_info(_, State) ->
+    {noreply, State}.
+
+-spec terminate(term(), term()) -> 'ok'.
+terminate(_Reason, _State) ->
+    ok.
+
+-spec code_change(term(), State, term()) -> {'ok', State}.
+code_change(_OldVsn, State, _Extra) ->
+    {ok, State}.
+
+%%-----------------------------------------------------------------
+%% Internal functions
+%%-----------------------------------------------------------------
+
+do_start(Resource, Cnt, Pid) ->
+    case maps:get(Pid, Cnt, undefined) of
+        undefined ->
+            Ref = erlang:monitor(process, Pid),
+            case any(Cnt) of
+                true ->
+                    {true, Cnt#{Pid=>{1, Ref}}};
+                false ->
+                    resource(Resource, true),
+                    {false, Cnt#{Pid=>{1, Ref}}}
+            end;
+        {N, Ref} ->
+            {true, Cnt#{Pid=>{N+1, Ref}}}
+    end.
+
+do_stop(Resource, Cnt0, Pid) ->
+    case maps:get(Pid, Cnt0, undefined) of
+        undefined ->
+            {any(Cnt0), Cnt0};
+        {1, Ref} ->
+            erlang:demonitor(Ref, [flush]),
+            Cnt = maps:remove(Pid, Cnt0),
+            case any(Cnt) of
+                true ->
+                    {true, Cnt};
+                false ->
+                    resource(Resource, false),
+                    {true, Cnt}
+            end;
+        {N, Ref} ->
+            {true, Cnt0#{Pid=>{N-1, Ref}}}
+    end.
+
+cleanup(Resource, Cnt0, Pid) ->
+    case maps:is_key(Pid, Cnt0) of
+        true ->
+            Cnt = maps:remove(Pid, Cnt0),
+            case any(Cnt) of
+                true ->
+                    Cnt;
+                false ->
+                    resource(Resource, false),
+                    Cnt
+            end;
+        false ->
+            Cnt0
+    end.
+
+any(Cnt) -> maps:size(Cnt) > 0.
+
+resource(scheduler_wall_time, Enable) ->
+    _ = erts_internal:scheduler_wall_time(Enable).
diff --git a/lib/kernel/src/net_kernel.erl b/lib/kernel/src/net_kernel.erl
index 7da89dd7cb..cdb10a7b12 100644
--- a/lib/kernel/src/net_kernel.erl
+++ b/lib/kernel/src/net_kernel.erl
@@ -70,8 +70,8 @@
 	 protocol_childspecs/0,
 	 epmd_module/0]).
 
--export([connect/1, disconnect/1, hidden_connect/1, passive_cnct/1]).
--export([hidden_connect_node/1]). %% explicit connect
+-export([disconnect/1, passive_cnct/1]).
+-export([hidden_connect_node/1]).
 -export([set_net_ticktime/1, set_net_ticktime/2, get_net_ticktime/0]).
 
 -export([node_info/1, node_info/2, nodes_info/0,
@@ -122,6 +122,7 @@
 
 -record(connection, {
 		     node,          %% remote node name
+                     conn_id,       %% Connection identity
 		     state,         %% pending | up | up_pending
 		     owner,         %% owner pid
 	             pending_owner, %% possible new owner
@@ -247,14 +248,15 @@ ticktime_res(A)      when is_atom(A)             -> A.
 
 %% Called though BIF's
 
-connect(Node) ->               do_connect(Node, normal, false).
 %%% Long timeout if blocked (== barred), only affects nodes with
 %%% {dist_auto_connect, once} set.
-passive_cnct(Node) ->              do_connect(Node, normal, true).
-disconnect(Node) ->            request({disconnect, Node}).
+passive_cnct(Node) ->
+    case request({passive_cnct, Node}) of
+        ignored -> false;
+        Other -> Other
+    end.
 
-%% connect but not seen
-hidden_connect(Node) ->        do_connect(Node, hidden, false).
+disconnect(Node) ->            request({disconnect, Node}).
 
 %% Should this node publish itself on Node?
 publish_on_node(Node) when is_atom(Node) ->
@@ -272,67 +274,30 @@ connect_node(Node) when is_atom(Node) ->
 hidden_connect_node(Node) when is_atom(Node) ->
     request({connect, hidden, Node}).
 
-do_connect(Node, Type, WaitForBarred) -> %% Type = normal | hidden
-    case catch ets:lookup(sys_dist, Node) of
-	{'EXIT', _} ->
-	    ?connect_failure(Node,{table_missing, sys_dist}),
-	    false;
-	[#barred_connection{}] ->
-	    case WaitForBarred of
-		false ->
-		    false;
-		true ->
-		    Pid = spawn(?MODULE,passive_connect_monitor,[self(),Node]),
-		    receive
-			{Pid, true} ->
-			    %%io:format("Net Kernel: barred connection (~p) "
-			    %%          "connected from other end.~n",[Node]),
-			    true;
-			{Pid, false} ->
-			    ?connect_failure(Node,{barred_connection,
-						   ets:lookup(sys_dist, Node)}),
-			    %%io:format("Net Kernel: barred connection (~p) "
-			    %%      "- failure.~n",[Node]),
-			    false
-		    end
-	    end;
-	Else ->
-	    case application:get_env(kernel, dist_auto_connect) of
-		{ok, never} ->
-		    ?connect_failure(Node,{dist_auto_connect,never}),
-		    false;
-		% This might happen due to connection close
-		% not beeing propagated to user space yet.
-		% Save the day by just not connecting...
-		{ok, once} when Else =/= [],
-				(hd(Else))#connection.state =:= up ->
-		    ?connect_failure(Node,{barred_connection,
-				ets:lookup(sys_dist, Node)}),
-		    false;
-		_ ->
-		    request({connect, Type, Node})
-	    end
-    end.
 
-passive_connect_monitor(Parent, Node) ->
+passive_connect_monitor(From, Node) ->
     ok = monitor_nodes(true,[{node_type,all}]),
-    case lists:member(Node,nodes([connected])) of
-	true ->
-	    ok = monitor_nodes(false,[{node_type,all}]),
-	    Parent ! {self(),true};
-	_ ->
-	    Ref = make_ref(),
-	    Tref = erlang:send_after(connecttime(),self(),Ref),
-	    receive
-		Ref ->
-		    ok = monitor_nodes(false,[{node_type,all}]),
-		    Parent ! {self(), false};
-		{nodeup,Node,_} ->
-		    ok = monitor_nodes(false,[{node_type,all}]),
-		    _ = erlang:cancel_timer(Tref),
-		    Parent ! {self(),true}
-	    end
-    end.
+    Reply = case lists:member(Node,nodes([connected])) of
+                true ->
+                    io:format("~p: passive_connect_monitor ~p\n", [self(), ?LINE]),
+                    true;
+                _ ->
+                    receive
+                        {nodeup,Node,_} ->
+                            io:format("~p: passive_connect_monitor ~p\n", [self(), ?LINE]),
+                            true
+                    after connecttime() ->
+                            io:format("~p: passive_connect_monitor ~p\n", [self(), ?LINE]),
+                            false
+                    end
+            end,
+    ok = monitor_nodes(false,[{node_type,all}]),
+    io:format("~p: passive_connect_monitor ~p\n", [self(), ?LINE]),
+    {Pid, Tag} = From,
+    io:format("~p: passive_connect_monitor ~p\n", [self(), ?LINE]),
+    erlang:send(Pid, {Tag, Reply}),
+    io:format("~p: passive_connect_monitor ~p\n", [self(), ?LINE]).
+
 
 %% If the net_kernel isn't running we ignore all requests to the
 %% kernel, thus basically accepting them :-)
@@ -394,40 +359,135 @@ init({Name, LongOrShortNames, TickT, CleanHalt}) ->
     end.
 
 
+do_auto_connect(Type, Node, ConnId, WaitForBarred, From, State) ->
+    ConnLookup = ets:lookup(sys_dist, Node),
+
+    case ConnLookup of
+        [#barred_connection{}] ->
+            case WaitForBarred of
+                false ->
+                    {reply, false, State};
+                true ->
+                    spawn(?MODULE,passive_connect_monitor,[From,Node]),
+                    {noreply, State}
+            end;
+
+        [#connection{conn_id=ConnId, state = up}] ->
+            {reply, true, State};
+        [#connection{conn_id=ConnId, waiting=Waiting}=Conn] ->
+            case From of
+                noreply -> ok;
+                _ -> ets:insert(sys_dist, Conn#connection{waiting = [From|Waiting]})
+            end,
+            {noreply, State};
+
+        _ ->
+            case application:get_env(kernel, dist_auto_connect) of
+                {ok, never} ->
+                    ?connect_failure(Node,{dist_auto_connect,never}),
+                    {reply, false, State};
+
+                %% This might happen due to connection close
+                %% not beeing propagated to user space yet.
+                %% Save the day by just not connecting...
+                {ok, once} when ConnLookup =/= [],
+                                (hd(ConnLookup))#connection.state =:= up ->
+                    ?connect_failure(Node,{barred_connection,
+                                           ets:lookup(sys_dist, Node)}),
+                    {reply, false, State};
+                _ ->
+                    case setup(ConnLookup, Node,ConnId,Type,From,State) of
+                        {ok, SetupPid} ->
+                            Owners = [{SetupPid, Node} | State#state.conn_owners],
+                            {noreply,State#state{conn_owners=Owners}};
+                        _Error  ->
+                            ?connect_failure(Node, {setup_call, failed, _Error}),
+                            {reply, false, State}
+                    end
+            end
+    end.
+
+
+do_explicit_connect([#connection{conn_id = ConnId, state = up}], _, _, ConnId, _From, State) ->
+    {reply, true, State};
+do_explicit_connect([#connection{conn_id = ConnId}=Conn], _, _, ConnId, From, State)
+  when Conn#connection.state =:= pending;
+       Conn#connection.state =:= up_pending ->
+    Waiting = Conn#connection.waiting,
+    ets:insert(sys_dist, Conn#connection{waiting = [From|Waiting]}),    
+    {noreply, State};
+do_explicit_connect([#barred_connection{}], Type, Node, ConnId, From , State) ->
+    %% Barred connection only affects auto_connect, ignore it.
+    do_explicit_connect([], Type, Node, ConnId, From , State);
+do_explicit_connect(ConnLookup, Type, Node, ConnId, From , State) ->
+    case setup(ConnLookup, Node,ConnId,Type,From,State) of
+        {ok, SetupPid} ->
+            Owners = [{SetupPid, Node} | State#state.conn_owners],
+            {noreply,State#state{conn_owners=Owners}};
+        _Error ->
+            ?connect_failure(Node, {setup_call, failed, _Error}),
+            {reply, false, State}
+    end.
+
+-define(ERTS_DIST_CON_ID_MASK, 16#ffffff).  % also in external.h
+
+verify_new_conn_id([], {Nr,_DHandle})
+  when (Nr band (bnot ?ERTS_DIST_CON_ID_MASK)) =:= 0 ->
+    true;
+verify_new_conn_id([#connection{conn_id = {Old,_}}], {New,_})
+  when New =:= ((Old+1) band ?ERTS_DIST_CON_ID_MASK) ->
+    true;
+verify_new_conn_id(_, _) ->
+    false.
+                                                              
+
+
 %% ------------------------------------------------------------
 %% handle_call.
 %% ------------------------------------------------------------
 
 %%
-%% Set up a connection to Node.
-%% The response is delayed until the connection is up and
-%% running.
+%% Passive auto-connect to Node.
+%% The response is delayed until the connection is up and running.
 %%
-handle_call({connect, _, Node}, From, State) when Node =:= node() ->
+handle_call({passive_cnct, Node}, From, State) when Node =:= node() ->
+    async_reply({reply, true, State}, From);
+handle_call({passive_cnct, Node}, From, State) ->
+    verbose({passive_cnct, Node}, 1, State),
+    Type = normal,
+    WaitForBarred = true,
+    R = case (catch erts_internal:new_connection(Node)) of
+            {Nr,_DHandle}=ConnId when is_integer(Nr) ->
+                do_auto_connect(Type, Node, ConnId, WaitForBarred, From, State);
+
+            _Error ->
+                error_logger:error_msg("~n** Cannot get connection id for node ~w~n",
+                                       [Node]),
+                {reply, false, State}
+        end,
+
+    return_call(R, From);
+
+%%
+%% Explicit connect
+%% The response is delayed until the connection is up and running.
+%%
+handle_call({connect, _, Node, _, _}, From, State) when Node =:= node() ->
     async_reply({reply, true, State}, From);
 handle_call({connect, Type, Node}, From, State) ->
     verbose({connect, Type, Node}, 1, State),
-    case ets:lookup(sys_dist, Node) of
-	[Conn] when Conn#connection.state =:= up ->
-	    async_reply({reply, true, State}, From);
-	[Conn] when Conn#connection.state =:= pending ->
-	    Waiting = Conn#connection.waiting,
-	    ets:insert(sys_dist, Conn#connection{waiting = [From|Waiting]}),
-	    {noreply, State};
-	[Conn] when Conn#connection.state =:= up_pending ->
-	    Waiting = Conn#connection.waiting,
-	    ets:insert(sys_dist, Conn#connection{waiting = [From|Waiting]}),
-	    {noreply, State};
-	_ ->
-	    case setup(Node,Type,From,State) of
-		{ok, SetupPid} ->
-		    Owners = [{SetupPid, Node} | State#state.conn_owners],
-		    {noreply,State#state{conn_owners=Owners}};
-		_  ->
-		    ?connect_failure(Node, {setup_call, failed}),
-		    async_reply({reply, false, State}, From)
-	    end
-    end;
+    ConnLookup = ets:lookup(sys_dist, Node),
+    R = case (catch erts_internal:new_connection(Node)) of
+            {Nr,_DHandle}=ConnId when is_integer(Nr) ->
+                do_explicit_connect(ConnLookup, Type, Node, ConnId, From, State);
+                    
+            _Error ->
+                error_logger:error_msg("~n** Cannot get connection id for node ~w~n",
+                                       [Node]),
+                {reply, false, State}                    
+        end,
+    return_call(R, From);
+            
 
 %%
 %% Close the connection to Node.
@@ -634,6 +694,26 @@ terminate(_Reason, State) ->
 %% ------------------------------------------------------------
 
 %%
+%% Asynchronous auto connect request
+%%
+handle_info({auto_connect,Node, Nr, DHandle}, State) ->
+    verbose({auto_connect, Node, Nr, DHandle}, 1, State),
+    ConnId = {Nr, DHandle},
+    NewState =
+        case do_auto_connect(normal, Node, ConnId, false, noreply, State) of
+            {noreply, S} ->           %% Pending connection
+                S;
+
+            {reply, true, S} ->  %% Already connected
+                S;
+
+            {reply, false, S} -> %% Connection refused
+                erts_internal:abort_connection(Node, ConnId),
+                S
+        end,
+    {noreply, NewState};
+
+%%
 %% accept a new connection.
 %%
 handle_info({accept,AcceptPid,Socket,Family,Proto}, State) ->
@@ -713,14 +793,23 @@ handle_info({AcceptPid, {accept_pending,MyNode,Node,Address,Type}}, State) ->
 	    AcceptPid ! {self(), {accept_pending, already_pending}},
 	    {noreply, State};
 	_ ->
-	    ets:insert(sys_dist, #connection{node = Node,
-					     state = pending,
-					     owner = AcceptPid,
-					     address = Address,
-					     type = Type}),
-	    AcceptPid ! {self(),{accept_pending,ok}},
-	    Owners = [{AcceptPid,Node} | State#state.conn_owners],
-	    {noreply, State#state{conn_owners = Owners}}
+            case (catch erts_internal:new_connection(Node)) of
+                {Nr,_DHandle}=ConnId when is_integer(Nr) ->
+                    ets:insert(sys_dist, #connection{node = Node,
+                                                     conn_id = ConnId,
+                                                     state = pending,
+                                                     owner = AcceptPid,
+                                                     address = Address,
+                                                     type = Type}),
+                    AcceptPid ! {self(),{accept_pending,ok}},
+                    Owners = [{AcceptPid,Node} | State#state.conn_owners],
+                    {noreply, State#state{conn_owners = Owners}};
+
+                _ ->
+                    error_logger:error_msg("~n** Cannot get connection id for node ~w~n",
+                                           [Node]),
+                    AcceptPid ! {self(),{accept_pending,nok_pending}}
+            end
     end;
 
 handle_info({SetupPid, {is_pending, Node}}, State) ->
@@ -906,6 +995,7 @@ pending_nodedown(Conn, Node, Type, State) ->
     % Don't bar connections that have never been alive
     %mark_sys_dist_nodedown(Node),
     % - instead just delete the node:
+    erts_internal:abort_connection(Node, Conn#connection.conn_id),
     ets:delete(sys_dist, Node),
     reply_waiting(Node,Conn#connection.waiting, false),
     case Type of
@@ -920,7 +1010,9 @@ up_pending_nodedown(Conn, Node, _Reason, _Type, State) ->
     AcceptPid = Conn#connection.pending_owner,
     Owners = State#state.conn_owners,
     Pend = lists:keydelete(AcceptPid, 1, State#state.pend_owners),
+    erts_internal:abort_connection(Node, Conn#connection.conn_id),
     Conn1 = Conn#connection { owner = AcceptPid,
+                              conn_id = erts_internal:new_connection(Node),
 			      pending_owner = undefined,
 			      state = pending },
     ets:insert(sys_dist, Conn1),
@@ -928,15 +1020,16 @@ up_pending_nodedown(Conn, Node, _Reason, _Type, State) ->
     State#state{conn_owners = [{AcceptPid,Node}|Owners], pend_owners = Pend}.
 
 
-up_nodedown(_Conn, Node, _Reason, Type, State) ->
-    mark_sys_dist_nodedown(Node),
+up_nodedown(Conn, Node, _Reason, Type, State) ->
+    mark_sys_dist_nodedown(Conn, Node),
     case Type of
 	normal -> ?nodedown(Node, State);
 	_ -> ok
     end,
     State.
 
-mark_sys_dist_nodedown(Node) ->
+mark_sys_dist_nodedown(Conn, Node) ->
+    erts_internal:abort_connection(Node, Conn#connection.conn_id),
     case application:get_env(kernel, dist_auto_connect) of
 	{ok, once} ->
 	    ets:insert(sys_dist, #barred_connection{node = Node});
@@ -1179,15 +1272,8 @@ spawn_func(_,{From,Tag},M,F,A,Gleader) ->
 %% Set up connection to a new node.
 %% -----------------------------------------------------------
 
-setup(Node,Type,From,State) ->
-    Allowed = State#state.allowed,
-    case lists:member(Node, Allowed) of
-	false when Allowed =/= [] ->
-	    error_msg("** Connection attempt with "
-		      "disallowed node ~w ** ~n", [Node]),
-	    {error, bad_node};
-	_ ->
-	    case select_mod(Node, State#state.listen) of
+setup(ConnLookup, Node,ConnId,Type,From,State) ->
+    case setup_check(ConnLookup, Node, ConnId, State) of
 		{ok, L} ->
 		    Mod = L#listen.module,
 		    LAddr = L#listen.address,
@@ -1200,18 +1286,45 @@ setup(Node,Type,From,State) ->
 		    Addr = LAddr#net_address {
 					      address = undefined,
 					      host = undefined },
+                    Waiting = case From of
+                                  noreply -> [];
+                                  _ -> [From]
+                              end,
 		    ets:insert(sys_dist, #connection{node = Node,
+                                                     conn_id = ConnId,
 						     state = pending,
 						     owner = Pid,
-						     waiting = [From],
+						     waiting = Waiting,
 						     address = Addr,
 						     type = normal}),
 		    {ok, Pid};
 		Error ->
 		    Error
-	    end
     end.
 
+setup_check(ConnLookup, Node, ConnId, State) ->
+    Allowed = State#state.allowed,    
+    case lists:member(Node, Allowed) of
+	false when Allowed =/= [] ->
+	    error_msg("** Connection attempt with "
+		      "disallowed node ~w ** ~n", [Node]),
+	    {error, bad_node};
+       _ ->
+            case verify_new_conn_id(ConnLookup, ConnId) of
+                false ->
+                    error_msg("** Connection attempt to ~w with "
+                              "bad connection id ~w ** ~n", [Node, ConnId]),
+                    {error, bad_conn_id};
+                true ->
+                    case select_mod(Node, State#state.listen) of
+                        {ok, _L}=OK -> OK;
+                        Error -> Error
+                    end
+            end
+    end.                    
+
+    
+
 %%
 %% Find a module that is willing to handle connection setup to Node
 %%
@@ -1652,6 +1765,11 @@ verbose(_, _, _) ->
 getnode(P) when is_pid(P) -> node(P);
 getnode(P) -> P.
 
+return_call({noreply, _State}=R, _From) ->
+    R;
+return_call(R, From) ->
+    async_reply(R, From).
+
 async_reply({reply, Msg, State}, From) ->
     async_gen_server_reply(From, Msg),
     {noreply, State}.
diff --git a/lib/kernel/src/os.erl b/lib/kernel/src/os.erl
index 0250783632..b5f19d4b99 100644
--- a/lib/kernel/src/os.erl
+++ b/lib/kernel/src/os.erl
@@ -25,6 +25,8 @@
 
 -include("file.hrl").
 
+-export_type([env_var_name/0, env_var_value/0, env_var_name_value/0, command_input/0]).
+
 %%% BIFs
 
 -export([getenv/0, getenv/1, getenv/2, getpid/0,
@@ -32,21 +34,29 @@
          putenv/2, set_signal/2, system_time/0, system_time/1,
 	 timestamp/0, unsetenv/1]).
 
--spec getenv() -> [string()].
+-type env_var_name() :: nonempty_string().
+
+-type env_var_value() :: string().
+
+-type env_var_name_value() :: nonempty_string().
+
+-type command_input() :: atom() | io_lib:chars().
+
+-spec getenv() -> [env_var_name_value()].
 
 getenv() -> erlang:nif_error(undef).
 
 -spec getenv(VarName) -> Value | false when
-      VarName :: string(),
-      Value :: string().
+      VarName :: env_var_name(),
+      Value :: env_var_value().
 
 getenv(_) ->
     erlang:nif_error(undef).
 
 -spec getenv(VarName, DefaultValue) -> Value when
-      VarName :: string(),
-      DefaultValue :: string(),
-      Value :: string().
+      VarName :: env_var_name(),
+      DefaultValue :: env_var_value(),
+      Value :: env_var_value().
 
 getenv(VarName, DefaultValue) ->
     case os:getenv(VarName) of
@@ -75,8 +85,8 @@ perf_counter(Unit) ->
       erlang:convert_time_unit(os:perf_counter(), perf_counter, Unit).
 
 -spec putenv(VarName, Value) -> true when
-      VarName :: string(),
-      Value :: string().
+      VarName :: env_var_name(),
+      Value :: env_var_value().
 
 putenv(_, _) ->
     erlang:nif_error(undef).
@@ -99,7 +109,7 @@ timestamp() ->
     erlang:nif_error(undef).
 
 -spec unsetenv(VarName) -> true when
-      VarName :: string().
+      VarName :: env_var_name().
 
 unsetenv(_) ->
     erlang:nif_error(undef).
@@ -178,7 +188,7 @@ verify_executable(Name0, [Ext|Rest], OrigExtensions) ->
     end;
 verify_executable(Name, [], OrigExtensions) when OrigExtensions =/= [""] -> %% Windows
     %% Will only happen on windows, hence case insensitivity
-    case can_be_full_name(string:to_lower(Name),OrigExtensions) of
+    case can_be_full_name(string:lowercase(Name),OrigExtensions) of
 	true ->
 	    verify_executable(Name,[""],[""]);
 	_ ->
@@ -232,10 +242,9 @@ extensions() ->
 
 %% Executes the given command in the default shell for the operating system.
 -spec cmd(Command) -> string() when
-      Command :: atom() | io_lib:chars().
+      Command :: os:command_input().
 cmd(Cmd) ->
-    validate(Cmd),
-    {SpawnCmd, SpawnOpts, SpawnInput, Eot} = mk_cmd(os:type(), Cmd),
+    {SpawnCmd, SpawnOpts, SpawnInput, Eot} = mk_cmd(os:type(), validate(Cmd)),
     Port = open_port({spawn, SpawnCmd}, [binary, stderr_to_stdout,
                                          stream, in, hide | SpawnOpts]),
     MonRef = erlang:monitor(port, Port),
@@ -255,8 +264,6 @@ mk_cmd({win32,Wtype}, Cmd) ->
                   {Cspec,_} -> lists:concat([Cspec," /c",Cmd])
               end,
     {Command, [], [], <<>>};
-mk_cmd(OsType,Cmd) when is_atom(Cmd) ->
-    mk_cmd(OsType, atom_to_list(Cmd));
 mk_cmd(_,Cmd) ->
     %% Have to send command in like this in order to make sh commands like
     %% cd and ulimit available
@@ -279,17 +286,33 @@ mk_cmd(_,Cmd) ->
      <<$\^D>>}.
 
 validate(Atom) when is_atom(Atom) ->
-    ok;
+    validate(atom_to_list(Atom));
 validate(List) when is_list(List) ->
-    validate1(List).
+    case validate1(List) of
+        false ->
+            List;
+        true -> 
+            %% Had zeros at end; remove them...
+            string:trim(List, trailing, [0])
+    end.
 
-validate1([C|Rest]) when is_integer(C) ->
+validate1([0|Rest]) ->
+    validate2(Rest);
+validate1([C|Rest]) when is_integer(C), C > 0 ->
     validate1(Rest);
 validate1([List|Rest]) when is_list(List) ->
-    validate1(List),
-    validate1(Rest);
+    validate1(List) or validate1(Rest);
 validate1([]) ->
-    ok.
+    false.
+
+%% Ensure that the rest is zero only...
+validate2([]) ->
+    true;
+validate2([0|Rest]) ->
+    validate2(Rest);
+validate2([List|Rest]) when is_list(List) ->
+    validate2(List),
+    validate2(Rest).
 
 get_data(Port, MonRef, Eot, Sofar) ->
     receive
diff --git a/lib/kernel/src/raw_file_io.erl b/lib/kernel/src/raw_file_io.erl
new file mode 100644
index 0000000000..e3c07c8f78
--- /dev/null
+++ b/lib/kernel/src/raw_file_io.erl
@@ -0,0 +1,75 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(raw_file_io).
+
+-export([open/2]).
+
+open(Filename, Modes) ->
+    %% Layers are applied in this order, and the listed modules will call this
+    %% function again as necessary. eg. a raw compressed delayed file in list
+    %% mode will walk through [_list -> _compressed -> _delayed -> _raw].
+    ModuleOrder = [{raw_file_io_list, fun match_list/1},
+                   {raw_file_io_compressed, fun match_compressed/1},
+                   {raw_file_io_delayed, fun match_delayed/1},
+                   {raw_file_io_raw, fun match_raw/1}],
+    open_1(ModuleOrder, Filename, add_implicit_modes(Modes)).
+open_1([], _Filename, _Modes) ->
+    error(badarg);
+open_1([{Module, Match} | Rest], Filename, Modes) ->
+    case lists:any(Match, Modes) of
+        true ->
+            {Options, ChildModes} =
+                lists:partition(fun(Mode) -> Match(Mode) end, Modes),
+            Module:open_layer(Filename, ChildModes, Options);
+        false ->
+            open_1(Rest, Filename, Modes)
+    end.
+
+%% 'read' and 'list' mode are enabled unless disabled by another option, so
+%% we'll explicitly add them to avoid duplicating this logic in child layers.
+add_implicit_modes(Modes0) ->
+    Modes1 = add_unless_matched(Modes0, fun match_writable/1, read),
+    add_unless_matched(Modes1, fun match_binary/1, list).
+add_unless_matched(Modes, Match, Default) ->
+    case lists:any(Match, Modes) of
+        false -> [Default | Modes];
+        true -> Modes
+    end.
+
+match_list(list) -> true;
+match_list(_Other) -> false.
+
+match_compressed(compressed) -> true;
+match_compressed(_Other) -> false.
+
+match_delayed({delayed_write, _Size, _Timeout}) -> true;
+match_delayed(delayed_write) -> true;
+match_delayed(_Other) -> false.
+
+match_raw(raw) -> true;
+match_raw(_Other) -> false.
+
+match_writable(write) -> true;
+match_writable(append) -> true;
+match_writable(exclusive) -> true;
+match_writable(_Other) -> false.
+
+match_binary(binary) -> true;
+match_binary(_Other) -> false.
diff --git a/lib/kernel/src/raw_file_io_compressed.erl b/lib/kernel/src/raw_file_io_compressed.erl
new file mode 100644
index 0000000000..d5ab042d25
--- /dev/null
+++ b/lib/kernel/src/raw_file_io_compressed.erl
@@ -0,0 +1,134 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(raw_file_io_compressed).
+
+-export([close/1, sync/1, datasync/1, truncate/1, advise/4, allocate/3,
+         position/2, write/2, pwrite/2, pwrite/3,
+         read_line/1, read/2, pread/2, pread/3]).
+
+%% OTP internal.
+-export([ipread_s32bu_p32bu/3, sendfile/8]).
+
+-export([open_layer/3]).
+
+-include("file_int.hrl").
+
+open_layer(Filename, Modes, Options) ->
+    IsAppend = lists:member(append, Modes),
+    IsDeflate = lists:member(write, Modes),
+    IsInflate = lists:member(read, Modes),
+    if
+        IsDeflate, IsInflate; IsAppend ->
+            {error, einval};
+        IsDeflate, not IsInflate ->
+            start_server_module(raw_file_io_deflate, Filename, Modes, Options);
+        IsInflate ->
+            start_server_module(raw_file_io_inflate, Filename, Modes, Options)
+    end.
+
+start_server_module(Module, Filename, Modes, Options) ->
+    Secret = make_ref(),
+    case gen_statem:start(Module, {self(), Secret, Options}, []) of
+        {ok, Pid} -> open_next_layer(Pid, Secret, Filename, Modes);
+        Other -> Other
+    end.
+
+open_next_layer(Pid, Secret, Filename, Modes) ->
+    case gen_statem:call(Pid, {'$open', Secret, Filename, Modes}, infinity) of
+        ok ->
+            PublicFd = #file_descriptor{
+                module = raw_file_io_compressed, data = {self(), Pid} },
+            {ok, PublicFd};
+        Other -> Other
+    end.
+
+close(Fd) ->
+    wrap_call(Fd, [close]).
+
+sync(Fd) ->
+    wrap_call(Fd, [sync]).
+datasync(Fd) ->
+    wrap_call(Fd, [datasync]).
+
+truncate(Fd) ->
+    wrap_call(Fd, [truncate]).
+
+advise(Fd, Offset, Length, Advise) ->
+    wrap_call(Fd, [advise, Offset, Length, Advise]).
+allocate(Fd, Offset, Length) ->
+    wrap_call(Fd, [allocate, Offset, Length]).
+
+position(Fd, Mark) ->
+    wrap_call(Fd, [position, Mark]).
+
+write(Fd, IOData) ->
+    try
+        CompactedData = erlang:iolist_to_iovec(IOData),
+        wrap_call(Fd, [write, CompactedData])
+    catch
+        error:badarg -> {error, badarg}
+    end.
+
+pwrite(Fd, Offset, IOData) ->
+    try
+        CompactedData = erlang:iolist_to_iovec(IOData),
+        wrap_call(Fd, [pwrite, Offset, CompactedData])
+    catch
+        error:badarg -> {error, badarg}
+    end.
+pwrite(Fd, LocBytes) ->
+    try
+        CompactedLocBytes =
+            [ {Offset, erlang:iolist_to_iovec(IOData)} ||
+              {Offset, IOData} <- LocBytes ],
+        wrap_call(Fd, [pwrite, CompactedLocBytes])
+    catch
+        error:badarg -> {error, badarg}
+    end.
+
+read_line(Fd) ->
+    wrap_call(Fd, [read_line]).
+read(Fd, Size) ->
+    wrap_call(Fd, [read, Size]).
+pread(Fd, Offset, Size) ->
+    wrap_call(Fd, [pread, Offset, Size]).
+pread(Fd, LocNums) ->
+    wrap_call(Fd, [pread, LocNums]).
+
+ipread_s32bu_p32bu(Fd, Offset, MaxSize) ->
+    wrap_call(Fd, [ipread_s32bu_p32bu, Offset, MaxSize]).
+
+sendfile(_,_,_,_,_,_,_,_) ->
+    {error, enotsup}.
+
+wrap_call(Fd, Command) ->
+    {_Owner, Pid} = get_fd_data(Fd),
+    try gen_statem:call(Pid, Command, infinity) of
+        Result -> Result
+    catch
+        exit:{noproc, _StackTrace} -> {error, einval}
+    end.
+
+get_fd_data(#file_descriptor{ data = Data }) ->
+    {Owner, _ServerPid} = Data,
+    case self() of
+        Owner -> Data;
+        _ -> error(not_on_controlling_process)
+    end.
diff --git a/lib/kernel/src/raw_file_io_deflate.erl b/lib/kernel/src/raw_file_io_deflate.erl
new file mode 100644
index 0000000000..acfc546743
--- /dev/null
+++ b/lib/kernel/src/raw_file_io_deflate.erl
@@ -0,0 +1,159 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(raw_file_io_deflate).
+
+-behavior(gen_statem).
+
+-export([init/1, callback_mode/0, terminate/3]).
+-export([opening/3, opened/3]).
+
+-include("file_int.hrl").
+
+-define(GZIP_WBITS, 16 + 15).
+
+callback_mode() -> state_functions.
+
+init({Owner, Secret, [compressed]}) ->
+    Monitor = monitor(process, Owner),
+    Z = zlib:open(),
+    ok = zlib:deflateInit(Z, default, deflated, ?GZIP_WBITS, 8, default),
+    Data =
+        #{ owner => Owner,
+           monitor => Monitor,
+           secret => Secret,
+           position => 0,
+           zlib => Z },
+    {ok, opening, Data}.
+
+opening({call, From}, {'$open', Secret, Filename, Modes}, #{ secret := Secret } = Data) ->
+    case raw_file_io:open(Filename, Modes) of
+        {ok, PrivateFd} ->
+            NewData = Data#{ handle => PrivateFd },
+            {next_state, opened, NewData, [{reply, From, ok}]};
+        Other ->
+            {stop_and_reply, normal, [{reply, From, Other}]}
+    end;
+opening(_Event, _Contents, _Data) ->
+    {keep_state_and_data, [postpone]}.
+
+%%
+
+opened(info, {'DOWN', Monitor, process, _Owner, Reason}, #{ monitor := Monitor } = Data) ->
+    if
+        Reason =/= kill -> flush_deflate_state(Data);
+        Reason =:= kill -> ignored
+    end,
+    {stop, shutdown};
+
+opened(info, _Message, _Data) ->
+    keep_state_and_data;
+
+opened({call, {Owner, _Tag} = From}, [close], #{ owner := Owner } = Data) ->
+    #{ handle := PrivateFd } = Data,
+    Response =
+        case flush_deflate_state(Data) of
+            ok -> ?CALL_FD(PrivateFd, close, []);
+            Other -> Other
+        end,
+    {stop_and_reply, normal, [{reply, From, Response}]};
+
+opened({call, {Owner, _Tag} = From}, [position, Mark], #{ owner := Owner } = Data) ->
+    case position(Data, Mark) of
+        {ok, NewData, Result} ->
+            Response = {ok, Result},
+            {keep_state, NewData, [{reply, From, Response}]};
+        Other ->
+            {keep_state_and_data, [{reply, From, Other}]}
+    end;
+
+opened({call, {Owner, _Tag} = From}, [write, IOVec], #{ owner := Owner } = Data) ->
+    case write(Data, IOVec) of
+        {ok, NewData} -> {keep_state, NewData, [{reply, From, ok}]};
+        Other -> {keep_state_and_data, [{reply, From, Other}]}
+    end;
+
+opened({call, {Owner, _Tag} = From}, [read, _Size], #{ owner := Owner }) ->
+    Response = {error, ebadf},
+    {keep_state_and_data, [{reply, From, Response}]};
+
+opened({call, {Owner, _Tag} = From}, [read_line], #{ owner := Owner }) ->
+    Response = {error, ebadf},
+    {keep_state_and_data, [{reply, From, Response}]};
+
+opened({call, {Owner, _Tag} = From}, _Command, #{ owner := Owner }) ->
+    Response = {error, enotsup},
+    {keep_state_and_data, [{reply, From, Response}]};
+
+opened({call, _From}, _Command, _Data) ->
+    %% The client functions filter this out, so we'll crash if the user does
+    %% anything stupid on purpose.
+    {shutdown, protocol_violation};
+
+opened(_Event, _Request, _Data) ->
+    keep_state_and_data.
+
+write(Data, IOVec) ->
+    #{ handle := PrivateFd, position := Position, zlib := Z } = Data,
+    UncompressedSize = iolist_size(IOVec),
+    case ?CALL_FD(PrivateFd, write, [zlib:deflate(Z, IOVec)]) of
+        ok -> {ok, Data#{ position := (Position + UncompressedSize) }};
+        Other -> Other
+    end.
+
+%%
+%% We support "seeking" forward as long as it isn't relative to EOF.
+%%
+%% Seeking is a bit of a misnomer as it's really just compressing zeroes until
+%% we reach the desired point, but it has always behaved like this.
+%%
+
+position(Data, Mark) when is_atom(Mark) ->
+    position(Data, {Mark, 0});
+position(Data, Offset) when is_integer(Offset) ->
+    position(Data, {bof, Offset});
+position(Data, {bof, Offset}) when is_integer(Offset) ->
+    position_1(Data, Offset);
+position(Data, {cur, Offset}) when is_integer(Offset) ->
+    #{ position := Position } = Data,
+    position_1(Data, Position + Offset);
+position(_Data, {eof, Offset}) when is_integer(Offset) ->
+    {error, einval};
+position(_Data, _Any) ->
+    {error, badarg}.
+
+position_1(#{ position := Desired } = Data, Desired) ->
+    {ok, Data, Desired};
+position_1(#{ position := Current } = Data, Desired) when Current < Desired ->
+    BytesToWrite = min(Desired - Current, 4 bsl 20),
+    case write(Data, <<0:(BytesToWrite)/unit:8>>) of
+        {ok, NewData} -> position_1(NewData, Desired);
+        Other -> Other
+    end;
+position_1(#{ position := Current }, Desired) when Current > Desired ->
+    {error, einval}.
+
+flush_deflate_state(#{ handle := PrivateFd, zlib := Z }) ->
+    case ?CALL_FD(PrivateFd, write, [zlib:deflate(Z, [], finish)]) of
+        ok -> ok;
+        Other -> Other
+    end.
+
+terminate(_Reason, _State, _Data) ->
+    ok.
diff --git a/lib/kernel/src/raw_file_io_delayed.erl b/lib/kernel/src/raw_file_io_delayed.erl
new file mode 100644
index 0000000000..d2ad7550a1
--- /dev/null
+++ b/lib/kernel/src/raw_file_io_delayed.erl
@@ -0,0 +1,320 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(raw_file_io_delayed).
+
+-behavior(gen_statem).
+
+-export([close/1, sync/1, datasync/1, truncate/1, advise/4, allocate/3,
+         position/2, write/2, pwrite/2, pwrite/3,
+         read_line/1, read/2, pread/2, pread/3]).
+
+%% OTP internal.
+-export([ipread_s32bu_p32bu/3, sendfile/8]).
+
+-export([open_layer/3]).
+
+-export([init/1, callback_mode/0, terminate/3]).
+-export([opening/3, opened/3]).
+
+-include("file_int.hrl").
+
+open_layer(Filename, Modes, Options) ->
+    Secret = make_ref(),
+    case gen_statem:start(?MODULE, {self(), Secret, Options}, []) of
+        {ok, Pid} ->
+            gen_statem:call(Pid, {'$open', Secret, Filename, Modes}, infinity);
+        Other ->
+            Other
+    end.
+
+callback_mode() -> state_functions.
+
+init({Owner, Secret, Options}) ->
+    Monitor = monitor(process, Owner),
+    Defaults =
+        #{ owner => Owner,
+           monitor => Monitor,
+           secret => Secret,
+           timer => none,
+           pid => self(),
+           buffer => prim_buffer:new(),
+           delay_size => 64 bsl 10,
+           delay_time => 2000 },
+    Data = fill_delay_values(Defaults, Options),
+    {ok, opening, Data}.
+
+fill_delay_values(Data, []) ->
+    Data;
+fill_delay_values(Data, [{delayed_write, Size, Time} | Options]) ->
+    fill_delay_values(Data#{ delay_size => Size, delay_time => Time }, Options);
+fill_delay_values(Data, [_ | Options]) ->
+    fill_delay_values(Data, Options).
+
+opening({call, From}, {'$open', Secret, Filename, Modes}, #{ secret := Secret } = Data) ->
+    case raw_file_io:open(Filename, Modes) of
+        {ok, PrivateFd} ->
+            PublicData = maps:with([owner, buffer, delay_size, pid], Data),
+            PublicFd = #file_descriptor{ module = ?MODULE, data = PublicData },
+
+            NewData = Data#{ handle => PrivateFd },
+            Response = {ok, PublicFd},
+            {next_state, opened, NewData, [{reply, From, Response}]};
+        Other ->
+            {stop_and_reply, normal, [{reply, From, Other}]}
+    end;
+opening(_Event, _Contents, _Data) ->
+    {keep_state_and_data, [postpone]}.
+
+%%
+
+opened(info, {'$timed_out', Secret}, #{ secret := Secret } = Data) ->
+    %% If the user writes something at this exact moment, the flush will fail
+    %% and the timer won't reset on the next write since the buffer won't be
+    %% empty (Unless we collided on a flush). We therefore reset the timeout to
+    %% ensure that data won't sit idle for extended periods of time.
+    case try_flush_write_buffer(Data) of
+        busy -> gen_statem:cast(self(), '$reset_timeout');
+        ok -> ok
+    end,
+    {keep_state, Data#{ timer => none }, []};
+
+opened(info, {'DOWN', Monitor, process, _Owner, Reason}, #{ monitor := Monitor } = Data) ->
+    if
+        Reason =/= kill -> try_flush_write_buffer(Data);
+        Reason =:= kill -> ignored
+    end,
+    {stop, shutdown};
+
+opened(info, _Message, _Data) ->
+    keep_state_and_data;
+
+opened({call, {Owner, _Tag} = From}, [close], #{ owner := Owner } = Data) ->
+    case flush_write_buffer(Data) of
+        ok ->
+            #{ handle := PrivateFd } = Data,
+            Response = ?CALL_FD(PrivateFd, close, []),
+            {stop_and_reply, normal, [{reply, From, Response}]};
+        Other ->
+            {stop_and_reply, normal, [{reply, From, Other}]}
+    end;
+
+opened({call, {Owner, _Tag} = From}, '$wait', #{ owner := Owner }) ->
+    %% Used in write/2 to synchronize writes on lock conflicts.
+    {keep_state_and_data, [{reply, From, ok}]};
+
+opened({call, {Owner, _Tag} = From}, '$synchronous_flush', #{ owner := Owner } = Data) ->
+    cancel_flush_timeout(Data),
+    Response = flush_write_buffer(Data),
+    {keep_state_and_data, [{reply, From, Response}]};
+
+opened({call, {Owner, _Tag} = From}, Command, #{ owner := Owner } = Data) ->
+    Response =
+        case flush_write_buffer(Data) of
+            ok -> dispatch_command(Data, Command);
+            Other -> Other
+        end,
+    {keep_state_and_data, [{reply, From, Response}]};
+
+opened({call, _From}, _Command, _Data) ->
+    %% The client functions filter this out, so we'll crash if the user does
+    %% anything stupid on purpose.
+    {shutdown, protocol_violation};
+
+opened(cast, '$reset_timeout', #{ delay_time := Timeout, secret := Secret } = Data) ->
+    cancel_flush_timeout(Data),
+    Timer = erlang:send_after(Timeout, self(), {'$timed_out', Secret}),
+    {keep_state, Data#{ timer => Timer }, []};
+
+opened(cast, _Message, _Data) ->
+    {keep_state_and_data, []}.
+
+dispatch_command(Data, [Function | Args]) ->
+    #{ handle := Handle } = Data,
+    Module = Handle#file_descriptor.module,
+    apply(Module, Function, [Handle | Args]).
+
+cancel_flush_timeout(#{ timer := none }) ->
+    ok;
+cancel_flush_timeout(#{ timer := Timer }) ->
+    _ = erlang:cancel_timer(Timer, [{async, true}]),
+    ok.
+
+try_flush_write_buffer(#{ buffer := Buffer, handle := PrivateFd }) ->
+    case prim_buffer:try_lock(Buffer) of
+        acquired ->
+            flush_write_buffer_1(Buffer, PrivateFd),
+            prim_buffer:unlock(Buffer),
+            ok;
+        busy ->
+            busy
+    end.
+
+%% This is only safe to use when there is no chance of conflict with the owner
+%% process, or in other words, "during synchronous calls outside of the locked
+%% section of write/2"
+flush_write_buffer(#{ buffer := Buffer, handle := PrivateFd }) ->
+    acquired = prim_buffer:try_lock(Buffer),
+    Result = flush_write_buffer_1(Buffer, PrivateFd),
+    prim_buffer:unlock(Buffer),
+    Result.
+
+flush_write_buffer_1(Buffer, PrivateFd) ->
+    case prim_buffer:size(Buffer) of
+        Size when Size > 0 ->
+            ?CALL_FD(PrivateFd, write, [prim_buffer:read_iovec(Buffer, Size)]);
+        0 ->
+            ok
+    end.
+
+terminate(_Reason, _State, _Data) ->
+    ok.
+
+%% Client functions
+
+write(Fd, IOData) ->
+    try
+        enqueue_write(Fd, erlang:iolist_to_iovec(IOData))
+    catch
+        error:badarg -> {error, badarg}
+    end.
+enqueue_write(_Fd, []) ->
+    ok;
+enqueue_write(Fd, IOVec) ->
+    %% get_fd_data will reject everyone except the process that opened the Fd,
+    %% so we can't race with anyone except the wrapper process.
+    #{ delay_size := DelaySize,
+       buffer := Buffer,
+       pid := Pid } = get_fd_data(Fd),
+    case prim_buffer:try_lock(Buffer) of
+        acquired ->
+            %% (The wrapper process will exit without flushing if we're killed
+            %% while holding the lock).
+            enqueue_write_locked(Pid, Buffer, DelaySize, IOVec);
+        busy ->
+            %% This can only happen while we're processing a timeout in the
+            %% wrapper process, so we perform a bogus call to get a completion
+            %% notification before trying again.
+            gen_statem:call(Pid, '$wait'),
+            enqueue_write(Fd, IOVec)
+    end.
+enqueue_write_locked(Pid, Buffer, DelaySize, IOVec) ->
+    %% The synchronous operations (write, forced flush) are safe since we're
+    %% running on the only process that can fill the buffer; a timeout being
+    %% processed just before $synchronous_flush will cause the flush to nop,
+    %% and a timeout sneaking in just before a synchronous write won't do
+    %% anything since the buffer is guaranteed to be empty at that point.
+    BufSize = prim_buffer:size(Buffer),
+    case is_iovec_smaller_than(IOVec, DelaySize - BufSize) of
+        true when BufSize > 0 ->
+            prim_buffer:write(Buffer, IOVec),
+            prim_buffer:unlock(Buffer);
+        true ->
+            prim_buffer:write(Buffer, IOVec),
+            prim_buffer:unlock(Buffer),
+            gen_statem:cast(Pid, '$reset_timeout');
+        false when BufSize > 0 ->
+            prim_buffer:write(Buffer, IOVec),
+            prim_buffer:unlock(Buffer),
+            gen_statem:call(Pid, '$synchronous_flush');
+        false ->
+            prim_buffer:unlock(Buffer),
+            gen_statem:call(Pid, [write, IOVec])
+    end.
+
+%% iolist_size/1 will always look through the entire list to get a precise
+%% amount, which is pretty inefficient since we only need to know whether we've
+%% hit the buffer threshold or not.
+%%
+%% We only handle the binary case since write/2 forcibly translates input to
+%% erlang:iovec().
+is_iovec_smaller_than(IOVec, Max) ->
+    is_iovec_smaller_than_1(IOVec, Max, 0).
+is_iovec_smaller_than_1(_IOVec, Max, Acc) when Acc >= Max ->
+    false;
+is_iovec_smaller_than_1([], _Max, _Acc) ->
+    true;
+is_iovec_smaller_than_1([Binary | Rest], Max, Acc) when is_binary(Binary) ->
+    is_iovec_smaller_than_1(Rest, Max, Acc + byte_size(Binary)).
+
+close(Fd) ->
+    wrap_call(Fd, [close]).
+
+sync(Fd) ->
+    wrap_call(Fd, [sync]).
+datasync(Fd) ->
+    wrap_call(Fd, [datasync]).
+
+truncate(Fd) ->
+    wrap_call(Fd, [truncate]).
+
+advise(Fd, Offset, Length, Advise) ->
+    wrap_call(Fd, [advise, Offset, Length, Advise]).
+allocate(Fd, Offset, Length) ->
+    wrap_call(Fd, [allocate, Offset, Length]).
+
+position(Fd, Mark) ->
+    wrap_call(Fd, [position, Mark]).
+
+pwrite(Fd, Offset, IOData) ->
+    try
+        CompactedData = erlang:iolist_to_iovec(IOData),
+        wrap_call(Fd, [pwrite, Offset, CompactedData])
+    catch
+        error:badarg -> {error, badarg}
+    end.
+pwrite(Fd, LocBytes) ->
+    try
+        CompactedLocBytes =
+            [ {Offset, erlang:iolist_to_iovec(IOData)} ||
+              {Offset, IOData} <- LocBytes ],
+        wrap_call(Fd, [pwrite, CompactedLocBytes])
+    catch
+        error:badarg -> {error, badarg}
+    end.
+
+read_line(Fd) ->
+    wrap_call(Fd, [read_line]).
+read(Fd, Size) ->
+    wrap_call(Fd, [read, Size]).
+pread(Fd, Offset, Size) ->
+    wrap_call(Fd, [pread, Offset, Size]).
+pread(Fd, LocNums) ->
+    wrap_call(Fd, [pread, LocNums]).
+
+ipread_s32bu_p32bu(Fd, Offset, MaxSize) ->
+    wrap_call(Fd, [ipread_s32bu_p32bu, Offset, MaxSize]).
+
+sendfile(_,_,_,_,_,_,_,_) ->
+    {error, enotsup}.
+
+wrap_call(Fd, Command) ->
+    #{ pid := Pid } = get_fd_data(Fd),
+    try gen_statem:call(Pid, Command, infinity) of
+        Result -> Result
+    catch
+        exit:{noproc, _StackTrace} -> {error, einval}
+    end.
+
+get_fd_data(#file_descriptor{ data = Data }) ->
+    #{ owner := Owner } = Data,
+    case self() of
+        Owner -> Data;
+        _ -> error(not_on_controlling_process)
+    end.
diff --git a/lib/kernel/src/raw_file_io_inflate.erl b/lib/kernel/src/raw_file_io_inflate.erl
new file mode 100644
index 0000000000..7e9780310c
--- /dev/null
+++ b/lib/kernel/src/raw_file_io_inflate.erl
@@ -0,0 +1,261 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(raw_file_io_inflate).
+
+-behavior(gen_statem).
+
+-export([init/1, callback_mode/0, terminate/3]).
+-export([opening/3, opened_gzip/3, opened_passthrough/3]).
+
+-include("file_int.hrl").
+
+-define(INFLATE_CHUNK_SIZE, (1 bsl 10)).
+-define(GZIP_WBITS, (16 + 15)).
+
+callback_mode() -> state_functions.
+
+init({Owner, Secret, [compressed]}) ->
+    Monitor = monitor(process, Owner),
+    %% We're using the undocumented inflateInit/3 to open the stream in
+    %% 'reset mode', which resets the inflate state at the end of every stream,
+    %% allowing us to read concatenated gzip files.
+    Z = zlib:open(),
+    ok = zlib:inflateInit(Z, ?GZIP_WBITS, reset),
+    Data =
+        #{ owner => Owner,
+           monitor => Monitor,
+           secret => Secret,
+           position => 0,
+           buffer => prim_buffer:new(),
+           zlib => Z },
+    {ok, opening, Data}.
+
+%% The old driver fell back to plain reads if the file didn't start with the
+%% magic gzip bytes.
+choose_decompression_state(PrivateFd) ->
+    State =
+        case ?CALL_FD(PrivateFd, read, [2]) of
+            {ok, <<16#1F, 16#8B>>} -> opened_gzip;
+            _Other -> opened_passthrough
+        end,
+    {ok, 0} = ?CALL_FD(PrivateFd, position, [0]),
+    State.
+
+opening({call, From}, {'$open', Secret, Filename, Modes}, #{ secret := Secret } = Data) ->
+    case raw_file_io:open(Filename, Modes) of
+        {ok, PrivateFd} ->
+            NextState = choose_decompression_state(PrivateFd),
+            NewData = Data#{ handle => PrivateFd },
+            {next_state, NextState, NewData, [{reply, From, ok}]};
+        Other ->
+            {stop_and_reply, normal, [{reply, From, Other}]}
+    end;
+opening(_Event, _Contents, _Data) ->
+    {keep_state_and_data, [postpone]}.
+
+internal_close(From, Data) ->
+    #{ handle := PrivateFd } = Data,
+    Response = ?CALL_FD(PrivateFd, close, []),
+    {stop_and_reply, normal, [{reply, From, Response}]}.
+
+opened_passthrough(info, {'DOWN', Monitor, process, _Owner, _Reason}, #{ monitor := Monitor }) ->
+    {stop, shutdown};
+
+opened_passthrough(info, _Message, _Data) ->
+    keep_state_and_data;
+
+opened_passthrough({call, {Owner, _Tag} = From}, [close], #{ owner := Owner } = Data) ->
+    internal_close(From, Data);
+
+opened_passthrough({call, {Owner, _Tag} = From}, [Method | Args], #{ owner := Owner } = Data) ->
+    #{ handle := PrivateFd } = Data,
+    Response = ?CALL_FD(PrivateFd, Method, Args),
+    {keep_state_and_data, [{reply, From, Response}]};
+
+opened_passthrough({call, _From}, _Command, _Data) ->
+    %% The client functions filter this out, so we'll crash if the user does
+    %% anything stupid on purpose.
+    {shutdown, protocol_violation};
+
+opened_passthrough(_Event, _Request, _Data) ->
+    keep_state_and_data.
+
+%%
+
+opened_gzip(info, {'DOWN', Monitor, process, _Owner, _Reason}, #{ monitor := Monitor }) ->
+    {stop, shutdown};
+
+opened_gzip(info, _Message, _Data) ->
+    keep_state_and_data;
+
+opened_gzip({call, {Owner, _Tag} = From}, [close], #{ owner := Owner } = Data) ->
+    internal_close(From, Data);
+
+opened_gzip({call, {Owner, _Tag} = From}, [position, Mark], #{ owner := Owner } = Data) ->
+    case position(Data, Mark) of
+        {ok, NewData, Result} ->
+            Response = {ok, Result},
+            {keep_state, NewData, [{reply, From, Response}]};
+        Other ->
+            {keep_state_and_data, [{reply, From, Other}]}
+    end;
+
+opened_gzip({call, {Owner, _Tag} = From}, [read, Size], #{ owner := Owner } = Data) ->
+    case read(Data, Size) of
+        {ok, NewData, Result} ->
+            Response = {ok, Result},
+            {keep_state, NewData, [{reply, From, Response}]};
+        Other ->
+            {keep_state_and_data, [{reply, From, Other}]}
+    end;
+
+opened_gzip({call, {Owner, _Tag} = From}, [read_line], #{ owner := Owner } = Data) ->
+    case read_line(Data) of
+        {ok, NewData, Result} ->
+            Response = {ok, Result},
+            {keep_state, NewData, [{reply, From, Response}]};
+        Other ->
+            {keep_state_and_data, [{reply, From, Other}]}
+    end;
+
+opened_gzip({call, {Owner, _Tag} = From}, [write, _IOData], #{ owner := Owner }) ->
+    Response = {error, ebadf},
+    {keep_state_and_data, [{reply, From, Response}]};
+
+opened_gzip({call, {Owner, _Tag} = From}, _Request, #{ owner := Owner }) ->
+    Response = {error, enotsup},
+    {keep_state_and_data, [{reply, From, Response}]};
+
+opened_gzip({call, _From}, _Request, _Data) ->
+    %% The client functions filter this out, so we'll crash if the user does
+    %% anything stupid on purpose.
+    {shutdown, protocol_violation};
+
+opened_gzip(_Event, _Request, _Data) ->
+    keep_state_and_data.
+
+%%
+
+read(#{ buffer := Buffer } = Data, Size) ->
+    try read_1(Data, Buffer, prim_buffer:size(Buffer), Size) of
+        Result -> Result
+    catch
+        error:badarg -> {error, badarg};
+        error:_ -> {error, eio}
+    end.
+read_1(Data, Buffer, BufferSize, ReadSize) when BufferSize >= ReadSize ->
+    #{ position := Position } = Data,
+    Decompressed = prim_buffer:read(Buffer, ReadSize),
+    {ok, Data#{ position => (Position + ReadSize) }, Decompressed};
+read_1(Data, Buffer, BufferSize, ReadSize) when BufferSize < ReadSize ->
+    #{ handle := PrivateFd } = Data,
+    case ?CALL_FD(PrivateFd, read, [?INFLATE_CHUNK_SIZE]) of
+        {ok, Compressed} ->
+            #{ zlib := Z } = Data,
+            Uncompressed = erlang:iolist_to_iovec(zlib:inflate(Z, Compressed)),
+            prim_buffer:write(Buffer, Uncompressed),
+            read_1(Data, Buffer, prim_buffer:size(Buffer), ReadSize);
+        eof when BufferSize > 0 ->
+            read_1(Data, Buffer, BufferSize, BufferSize);
+        Other ->
+            Other
+    end.
+
+read_line(#{ buffer := Buffer } = Data) ->
+    try read_line_1(Data, Buffer, prim_buffer:find_byte_index(Buffer, $\n)) of
+        {ok, NewData, Decompressed} -> {ok, NewData, Decompressed};
+        Other -> Other
+    catch
+        error:badarg -> {error, badarg};
+        error:_ -> {error, eio}
+    end.
+
+read_line_1(Data, Buffer, not_found) ->
+    #{ handle := PrivateFd, zlib := Z } = Data,
+    case ?CALL_FD(PrivateFd, read, [?INFLATE_CHUNK_SIZE]) of
+        {ok, Compressed} ->
+            Uncompressed = erlang:iolist_to_iovec(zlib:inflate(Z, Compressed)),
+            prim_buffer:write(Buffer, Uncompressed),
+            read_line_1(Data, Buffer, prim_buffer:find_byte_index(Buffer, $\n));
+        eof ->
+            case prim_buffer:size(Buffer) of
+                Size when Size > 0 -> {ok, prim_buffer:read(Buffer, Size)};
+                Size when Size =:= 0 -> eof
+            end;
+        Error ->
+            Error
+    end;
+read_line_1(Data, Buffer, {ok, LFIndex}) ->
+    %% Translate CRLF into just LF, completely ignoring which encoding is used,
+    %% but treat the file position as including CR.
+    #{ position := Position } = Data,
+    NewData = Data#{ position => (Position + LFIndex + 1) },
+    CRIndex = (LFIndex - 1),
+    TranslatedLine =
+        case prim_buffer:read(Buffer, LFIndex + 1) of
+            <<Line:CRIndex/binary, "\r\n">> -> <<Line/binary, "\n">>;
+            Line -> Line
+        end,
+    {ok, NewData, TranslatedLine}.
+
+%%
+%% We support seeking in both directions as long as it isn't relative to EOF.
+%%
+%% Seeking backwards is extremely inefficient since we have to seek to the very
+%% beginning and then decompress up to the desired point.
+%%
+
+position(Data, Mark) when is_atom(Mark) ->
+    position(Data, {Mark, 0});
+position(Data, Offset) when is_integer(Offset) ->
+    position(Data, {bof, Offset});
+position(Data, {bof, Offset}) when is_integer(Offset) ->
+    position_1(Data, Offset);
+position(Data, {cur, Offset}) when is_integer(Offset) ->
+    #{ position := Position } = Data,
+    position_1(Data, Position + Offset);
+position(_Data, {eof, Offset}) when is_integer(Offset) ->
+    {error, einval};
+position(_Data, _Other) ->
+    {error, badarg}.
+
+position_1(_Data, Desired) when Desired < 0 ->
+    {error, einval};
+position_1(#{ position := Desired } = Data, Desired) ->
+    {ok, Data, Desired};
+position_1(#{ position := Current } = Data, Desired) when Current < Desired ->
+    case read(Data, min(Desired - Current, ?INFLATE_CHUNK_SIZE)) of
+        {ok, NewData, _Data} -> position_1(NewData, Desired);
+        eof -> {ok, Data, Current};
+        Other -> Other
+    end;
+position_1(#{ position := Current } = Data, Desired) when Current > Desired ->
+    #{ handle := PrivateFd, buffer := Buffer, zlib := Z } = Data,
+    case ?CALL_FD(PrivateFd, position, [bof]) of
+        {ok, 0} ->
+            ok = zlib:inflateReset(Z),
+            prim_buffer:wipe(Buffer),
+            position_1(Data#{ position => 0 }, Desired);
+        Other ->
+            Other
+    end.
+
+terminate(_Reason, _State, _Data) ->
+    ok.
diff --git a/lib/kernel/src/raw_file_io_list.erl b/lib/kernel/src/raw_file_io_list.erl
new file mode 100644
index 0000000000..2e16e63f0e
--- /dev/null
+++ b/lib/kernel/src/raw_file_io_list.erl
@@ -0,0 +1,128 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(raw_file_io_list).
+
+-export([close/1, sync/1, datasync/1, truncate/1, advise/4, allocate/3,
+         position/2, write/2, pwrite/2, pwrite/3,
+         read_line/1, read/2, pread/2, pread/3]).
+
+%% OTP internal.
+-export([ipread_s32bu_p32bu/3, sendfile/8]).
+
+-export([open_layer/3]).
+
+-include("file_int.hrl").
+
+open_layer(Filename, Modes, [list]) ->
+    case raw_file_io:open(Filename, [binary | Modes]) of
+        {ok, PrivateFd} -> {ok, make_public_fd(PrivateFd, Modes)};
+        Other -> Other
+    end.
+
+%% We can skip wrapping the file if it's write-only since only read operations
+%% are affected by list mode. Since raw_file_io fills in all implicit options
+%% for us, all we need to do is check whether 'read' is among them.
+make_public_fd(PrivateFd, Modes) ->
+    case lists:member(read, Modes) of
+        true -> #file_descriptor{ module = ?MODULE, data = PrivateFd };
+        false -> PrivateFd
+    end.
+
+close(Fd) ->
+    PrivateFd = Fd#file_descriptor.data,
+    ?CALL_FD(PrivateFd, close, []).
+
+sync(Fd) ->
+    PrivateFd = Fd#file_descriptor.data,
+    ?CALL_FD(PrivateFd, sync, []).
+datasync(Fd) ->
+    PrivateFd = Fd#file_descriptor.data,
+    ?CALL_FD(PrivateFd, datasync, []).
+
+truncate(Fd) ->
+    PrivateFd = Fd#file_descriptor.data,
+    ?CALL_FD(PrivateFd, truncate, []).
+
+advise(Fd, Offset, Length, Advise) ->
+    PrivateFd = Fd#file_descriptor.data,
+    ?CALL_FD(PrivateFd, advise, [Offset, Length, Advise]).
+allocate(Fd, Offset, Length) ->
+    PrivateFd = Fd#file_descriptor.data,
+    ?CALL_FD(PrivateFd, allocate, [Offset, Length]).
+
+position(Fd, Mark) ->
+    PrivateFd = Fd#file_descriptor.data,
+    ?CALL_FD(PrivateFd, position, [Mark]).
+
+write(Fd, IOData) ->
+    PrivateFd = Fd#file_descriptor.data,
+    ?CALL_FD(PrivateFd, write, [IOData]).
+
+pwrite(Fd, Offset, IOData) ->
+    PrivateFd = Fd#file_descriptor.data,
+    ?CALL_FD(PrivateFd, pwrite, [Offset, IOData]).
+pwrite(Fd, LocBytes) ->
+    PrivateFd = Fd#file_descriptor.data,
+    ?CALL_FD(PrivateFd, pwrite, [LocBytes]).
+
+read_line(Fd) ->
+    PrivateFd = Fd#file_descriptor.data,
+    case ?CALL_FD(PrivateFd, read_line, []) of
+        {ok, Binary} -> {ok, binary_to_list(Binary)};
+        Other -> Other
+    end.
+read(Fd, Size) ->
+    PrivateFd = Fd#file_descriptor.data,
+    case ?CALL_FD(PrivateFd, read, [Size]) of
+        {ok, Binary} -> {ok, binary_to_list(Binary)};
+        Other -> Other
+    end.
+pread(Fd, Offset, Size) ->
+    PrivateFd = Fd#file_descriptor.data,
+    case ?CALL_FD(PrivateFd, pread, [Offset, Size]) of
+        {ok, Binary} -> {ok, binary_to_list(Binary)};
+        Other -> Other
+    end.
+pread(Fd, LocNums) ->
+    PrivateFd = Fd#file_descriptor.data,
+    case ?CALL_FD(PrivateFd, pread, [LocNums]) of
+        {ok, LocResults} ->
+            TranslatedResults =
+                [ case Result of
+                      Result when is_binary(Result) -> binary_to_list(Result);
+                      eof -> eof
+                  end || Result <- LocResults ],
+            {ok, TranslatedResults};
+        Other -> Other
+    end.
+
+ipread_s32bu_p32bu(Fd, Offset, MaxSize) ->
+    PrivateFd = Fd#file_descriptor.data,
+    case ?CALL_FD(PrivateFd, ipread_s32bu_p32bu, [Offset, MaxSize]) of
+        {ok, {Size, Pointer, Binary}} when is_binary(Binary) ->
+            {ok, {Size, Pointer, binary_to_list(Binary)}};
+        Other ->
+            Other
+    end.
+
+sendfile(Fd, Dest, Offset, Bytes, ChunkSize, Headers, Trailers, Flags) ->
+    Args = [Dest, Offset, Bytes, ChunkSize, Headers, Trailers, Flags],
+    PrivateFd = Fd#file_descriptor.data,
+    ?CALL_FD(PrivateFd, sendfile, Args).
diff --git a/lib/kernel/src/raw_file_io_raw.erl b/lib/kernel/src/raw_file_io_raw.erl
new file mode 100644
index 0000000000..9a9fe78eb1
--- /dev/null
+++ b/lib/kernel/src/raw_file_io_raw.erl
@@ -0,0 +1,25 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(raw_file_io_raw).
+
+-export([open_layer/3]).
+
+open_layer(Filename, Modes, [raw]) ->
+    prim_file:open(Filename, [raw | Modes]).
diff --git a/lib/kernel/test/disk_log_SUITE.erl b/lib/kernel/test/disk_log_SUITE.erl
index fe2fc778f2..7beaadb1d6 100644
--- a/lib/kernel/test/disk_log_SUITE.erl
+++ b/lib/kernel/test/disk_log_SUITE.erl
@@ -89,8 +89,6 @@
 	 dist_terminate/1, dist_accessible/1, dist_deadlock/1,
          dist_open2/1, other_groups/1,
 
-         evil/1,
-
          otp_6278/1, otp_10131/1]).
 
 -export([head_fun/1, hf/0, lserv/1, 
@@ -123,7 +121,7 @@
 	[halt_int, wrap_int, halt_ext, wrap_ext, read_mode, head,
 	 notif, new_idx_vsn, reopen, block, unblock, open, close,
 	 error, chunk, truncate, many_users, info, change_size,
-	 change_attribute, distribution, evil, otp_6278, otp_10131]).
+	 change_attribute, distribution, otp_6278, otp_10131]).
 
 %% These test cases should be skipped if the VxWorks card is 
 %% configured without NFS cache.
@@ -149,7 +147,7 @@ all() ->
      {group, open}, {group, close}, {group, error}, chunk,
      truncate, many_users, {group, info},
      {group, change_size}, change_attribute,
-     {group, distribution}, evil, otp_6278, otp_10131].
+     {group, distribution}, otp_6278, otp_10131].
 
 groups() -> 
     [{halt_int, [], [halt_int_inf, {group, halt_int_sz}]},
@@ -4676,119 +4674,6 @@ other_groups(Conf) when is_list(Conf) ->
 
     ok.
 
--define(MAX, ?MAX_FWRITE_CACHE). % as in disk_log_1.erl
-%% Evil cases such as closed file descriptor port.
-evil(Conf) when is_list(Conf) ->
-    Dir = ?privdir(Conf),
-    File = filename:join(Dir, "n.LOG"),
-    Log = n,
-
-    %% Not a very thorough test.
-
-    ok = setup_evil_filled_cache_wrap(Log, Dir),
-    {error, {file_error,_,einval}} = disk_log:log(Log, apa),
-    ok = disk_log:close(Log),
-
-    ok = setup_evil_filled_cache_halt(Log, Dir),
-    {error, {file_error,_,einval}} = disk_log:truncate(Log, apa),
-    ok = stop_evil(Log),
-
-    %% White box test. 
-    file:delete(File),
-    Ports0 = erlang:ports(),
-    {ok, Log} = disk_log:open([{name,Log},{file,File},{type,halt},
-                                     {size,?MAX+50},{format,external}]),
-    [Fd] = erlang:ports() -- Ports0,
-    {B,_} = x_mk_bytes(30),
-    ok = disk_log:blog(Log, <<0:(?MAX-1)/unit:8>>),
-    exit(Fd, kill),
-    {error, {file_error,_,einval}} = disk_log:blog_terms(Log, [B,B]),
-    ok= disk_log:close(Log),
-    file:delete(File),
-
-    ok = setup_evil_wrap(Log, Dir),
-    {error, {file_error,_,einval}} = disk_log:close(Log),
-
-    ok = setup_evil_wrap(Log, Dir),
-    {error, {file_error,_,einval}} = disk_log:log(Log, apa),
-    ok = stop_evil(Log),
-
-    ok = setup_evil_halt(Log, Dir),
-    {error, {file_error,_,einval}} = disk_log:log(Log, apa),
-    ok = stop_evil(Log),
-
-    ok = setup_evil_wrap(Log, Dir),
-    {error, {file_error,_,einval}} = disk_log:reopen(Log, apa),
-    {error, {file_error,_,einval}} = disk_log:reopen(Log, apa),
-    ok = stop_evil(Log),
-
-    ok = setup_evil_wrap(Log, Dir),
-    {error, {file_error,_,einval}} = disk_log:reopen(Log, apa),
-    ok = stop_evil(Log),
-
-    ok = setup_evil_wrap(Log, Dir),
-    {error, {file_error,_,einval}} = disk_log:inc_wrap_file(Log),
-    ok = stop_evil(Log),
-
-    ok = setup_evil_wrap(Log, Dir),
-    {error, {file_error,_,einval}} = disk_log:chunk(Log, start),
-    ok = stop_evil(Log),
-
-    ok = setup_evil_wrap(Log, Dir),
-    {error, {file_error,_,einval}} = disk_log:truncate(Log),
-    ok = stop_evil(Log),
-
-    ok = setup_evil_wrap(Log, Dir),
-    {error, {file_error,_,einval}} = disk_log:chunk_step(Log, start, 1),
-    ok = stop_evil(Log),
-
-    io:format("messages: ~p~n", [erlang:process_info(self(), messages)]),
-    del(File, 2),
-    file:delete(File),
-    ok.
-
-setup_evil_wrap(Log, Dir) ->
-    setup_evil(Log, [{type,wrap},{size,{100,2}}], Dir).
-
-setup_evil_halt(Log, Dir) ->
-    setup_evil(Log, [{type,halt},{size,10000}], Dir).
-
-setup_evil(Log, Args, Dir) ->
-    File = filename:join(Dir, lists:concat([Log, ".LOG"])),
-    file:delete(File),
-    del(File, 2),
-    ok = disk_log:start(),
-    Ports0 = erlang:ports(),
-    {ok, Log} = disk_log:open([{name,Log},{file,File} | Args]),
-    [Fd] = erlang:ports() -- Ports0,
-    exit(Fd, kill),
-    ok = disk_log:log_terms(n, [<<0:10/unit:8>>]),
-    timer:sleep(2500), % TIMEOUT in disk_log_1.erl is 2000
-    ok.
-
-stop_evil(Log) ->
-    {error, _} = disk_log:close(Log),
-    ok.
-
-setup_evil_filled_cache_wrap(Log, Dir) ->
-    setup_evil_filled_cache(Log, [{type,wrap},{size,{?MAX,2}}], Dir).
-
-setup_evil_filled_cache_halt(Log, Dir) ->
-    setup_evil_filled_cache(Log, [{type,halt},{size,infinity}], Dir).
-
-%% The cache is filled, and the file descriptor port gone.
-setup_evil_filled_cache(Log, Args, Dir) ->
-    File = filename:join(Dir, lists:concat([Log, ".LOG"])),
-    file:delete(File),
-    del(File, 2),
-    ok = disk_log:start(),
-    Ports0 = erlang:ports(),
-    {ok, Log} = disk_log:open([{name,Log},{file,File} | Args]),
-    [Fd] = erlang:ports() -- Ports0,
-    ok = disk_log:log_terms(n, [<<0:?MAX/unit:8>>]),
-    exit(Fd, kill),
-    ok.
-
 %% OTP-6278. open/1 creates no status or crash report.
 otp_6278(Conf) when is_list(Conf) ->
     Dir = ?privdir(Conf),
diff --git a/lib/kernel/test/erl_distribution_wb_SUITE.erl b/lib/kernel/test/erl_distribution_wb_SUITE.erl
index 03aaee56b7..8256444bdc 100644
--- a/lib/kernel/test/erl_distribution_wb_SUITE.erl
+++ b/lib/kernel/test/erl_distribution_wb_SUITE.erl
@@ -61,10 +61,13 @@
 %% From R9 and forward extended references is compulsory
 %% From R10 and forward extended pids and ports are compulsory
 %% From R20 and forward UTF8 atoms are compulsory
+%% From R21 and forward NEW_FUN_TAGS is compulsory (no more tuple fallback {fun, ...})
 -define(COMPULSORY_DFLAGS, (?DFLAG_EXTENDED_REFERENCES bor
                             ?DFLAG_EXTENDED_PIDS_PORTS bor
-                            ?DFLAG_UTF8_ATOMS)).
+                            ?DFLAG_UTF8_ATOMS bor
+                            ?DFLAG_NEW_FUN_TAGS)).
 
+-define(PASS_THROUGH, $p).
 
 -define(shutdown(X), exit(X)).
 -define(int16(X), [((X) bsr 8) band 16#ff, (X) band 16#ff]).
@@ -674,15 +677,16 @@ build_rex_message(Cookie,OurName) ->
 %% Receive a distribution message    
 recv_message(Socket) ->
     case gen_tcp:recv(Socket, 0) of
+        {ok,[]} ->
+            recv_message(Socket);  %% a tick, ignore
 	{ok,Data} ->
 	    B0 = list_to_binary(Data),
-	    {_,B1} = erlang:split_binary(B0,1),
-	    Header = binary_to_term(B1),
-	    Siz = byte_size(term_to_binary(Header)),
-	    {_,B2} = erlang:split_binary(B1,Siz),
+	    <<?PASS_THROUGH, B1/binary>> = B0,
+	    {Header,Siz} = binary_to_term(B1,[used]),
+	    <<_:Siz/binary,B2/binary>> = B1,
 	    Message = case (catch binary_to_term(B2)) of
 			  {'EXIT', _} ->
-			      could_not_digest_message;
+			      {could_not_digest_message,B2};
 			  Other ->
 			      Other
 		      end,
diff --git a/lib/kernel/test/erl_prim_loader_SUITE.erl b/lib/kernel/test/erl_prim_loader_SUITE.erl
index b6417210b9..3502a4ad08 100644
--- a/lib/kernel/test/erl_prim_loader_SUITE.erl
+++ b/lib/kernel/test/erl_prim_loader_SUITE.erl
@@ -33,6 +33,7 @@
 	 primary_archive/1, virtual_dir_in_archive/1,
 	 get_modules/1]).
 
+-define(PRIM_FILE, prim_file).
 
 %%-----------------------------------------------------------------
 %% Test suite for erl_prim_loader. (Most code is run during system start/stop.)
@@ -461,7 +462,7 @@ primary_archive(Config) when is_list(Config) ->
     %% Set primary archive 
     ExpectedEbins = [Archive, DictDir ++ "/ebin", DummyDir ++ "/ebin"],
     io:format("ExpectedEbins: ~p\n", [ExpectedEbins]),
-    {ok, FileInfo} = prim_file:read_file_info(Archive),
+    {ok, FileInfo} = ?PRIM_FILE:read_file_info(Archive),
     {ok, Ebins} = rpc:call(Node, erl_prim_loader, set_primary_archive,
 			   [Archive, ArchiveBin, FileInfo,
 			    fun escript:parse_file/1]),
diff --git a/lib/kernel/test/file_SUITE.erl b/lib/kernel/test/file_SUITE.erl
index 119e1f24bb..0cb8087a76 100644
--- a/lib/kernel/test/file_SUITE.erl
+++ b/lib/kernel/test/file_SUITE.erl
@@ -39,6 +39,8 @@
 -define(FILE_FIN_PER_TESTCASE(Config), Config).
 -endif.
 
+-define(PRIM_FILE, prim_file).
+
 -module(?FILE_SUITE).
 
 -export([all/0, suite/0,groups/0,init_per_suite/1, end_per_suite/1, 
@@ -97,6 +99,12 @@
 
 -export([unicode_mode/1]).
 
+-export([volume_relative_paths/1]).
+
+-export([tiny_writes/1, tiny_writes_delayed/1,
+         large_writes/1, large_writes_delayed/1,
+         tiny_reads/1, tiny_reads_ahead/1]).
+
 %% Debug exports
 -export([create_file_slow/2, create_file/2, create_bin/2]).
 -export([verify_file/2, verify_bin/3]).
@@ -107,6 +115,8 @@
 -export([disc_free/1, memsize/0]).
 
 -include_lib("common_test/include/ct.hrl").
+-include_lib("common_test/include/ct_event.hrl").
+
 -include_lib("kernel/include/file.hrl").
 
 -define(THROW_ERROR(RES), throw({fail, ?LINE, RES})).
@@ -118,13 +128,13 @@ suite() ->
 
 all() -> 
     [unicode, altname, read_write_file, {group, dirs},
-     {group, files}, delete, rename, names, {group, errors},
-     {group, compression}, {group, links}, copy,
+     {group, files}, delete, rename, names, volume_relative_paths,
+     {group, errors}, {group, compression}, {group, links}, copy,
      delayed_write, read_ahead, segment_read, segment_write,
      ipread, pid2name, interleaved_read_write, otp_5814, otp_10852,
      large_file, large_write, read_line_1, read_line_2, read_line_3,
      read_line_4, standard_io, old_io_protocol,
-     unicode_mode
+     unicode_mode, {group, bench}
     ].
 
 groups() -> 
@@ -154,11 +164,19 @@ groups() ->
        write_compressed, compress_errors, catenated_gzips,
        compress_async_crash]},
      {links, [],
-      [make_link, read_link_info_for_non_link, symlinks]}].
+      [make_link, read_link_info_for_non_link, symlinks]},
+     {bench, [],
+      [tiny_writes, tiny_writes_delayed,
+       large_writes, large_writes_delayed,
+       tiny_reads, tiny_reads_ahead]}].
 
 init_per_group(_GroupName, Config) ->
     Config.
 
+end_per_group(bench, Config) ->
+    ScratchDir = proplists:get_value(priv_dir, Config),
+    file:delete(filename:join(ScratchDir, "benchmark_scratch_file")),
+    Config;
 end_per_group(_GroupName, Config) ->
     Config.
 
@@ -473,7 +491,7 @@ um_check_unicode(_Utf8Bin, {ok, _ListOrBin}, _, _UTF8_) ->
 um_filename(Bin, Dir, Options) when is_binary(Bin) ->
     um_filename(binary_to_list(Bin), Dir, Options);
 um_filename(Str = [_|_], Dir, Options) ->
-    Name = hd(string:tokens(Str, ":")),
+    Name = hd(string:lexemes(Str, ":")),
     Enc = atom_to_list(proplists:get_value(encoding, Options, latin1)),
     File = case lists:member(binary, Options) of
 	       true ->
@@ -638,6 +656,10 @@ cur_dir_0(Config) when is_list(Config) ->
 	    {ok,NewDirFiles} = ?FILE_MODULE:list_dir("."),
 	    true = lists:member(UncommonName,NewDirFiles),
 
+	    %% Ensure that we get the same result with a trailing slash; the
+	    %% APIs used on Windows will choke on them if passed directly.
+	    {ok,NewDirFiles} = ?FILE_MODULE:list_dir("./"),
+
 	    %% Delete the directory and return to the old current directory
 	    %% and check that the created file isn't there (too!)
 	    expect({error, einval}, {error, eacces}, 
@@ -690,10 +712,15 @@ win_cur_dir_1(_Config) ->
     %% Get the drive letter from the current directory,
     %% and try to get current directory for that drive.
 
-    [Drive,$:|_] = BaseDir,
-    {ok,BaseDir} = ?FILE_MODULE:get_cwd([Drive,$:]),
+    [CurDrive,$:|_] = BaseDir,
+    {ok,BaseDir} = ?FILE_MODULE:get_cwd([CurDrive,$:]),
     io:format("BaseDir = ~s\n", [BaseDir]),
 
+    %% We should error out on non-existent drives. Any reasonable system will
+    %% have at least one.
+    CurDirs = [?FILE_MODULE:get_cwd([Drive,$:]) || Drive <- lists:seq($A, $Z)],
+    lists:member({error,eaccess}, CurDirs),
+
     %% Unfortunately, there is no way to move away from the
     %% current drive as we can't use the "subst" command from
     %% a SSH connection. We can't test any more.
@@ -831,7 +858,7 @@ no_untranslatable_names() ->
     end.
 
 start_node(Name, Args) ->
-    [_,Host] = string:tokens(atom_to_list(node()), "@"),
+    [_,Host] = string:lexemes(atom_to_list(node()), "@"),
     ct:log("Trying to start ~w@~s~n", [Name,Host]),
     case test_server:start_node(Name, peer, [{args,Args}]) of
 	{error,Reason} ->
@@ -1019,6 +1046,23 @@ close(Config) when is_list(Config) ->
     Val = ?FILE_MODULE:close(Fd1),
     io:format("Second close gave: ~p",[Val]),
 
+    %% All operations on a closed raw file should EINVAL, even if they're not
+    %% supported on the current platform.
+    {ok,Fd2} = ?FILE_MODULE:open(Name, [read, write, raw]),
+    ok = ?FILE_MODULE:close(Fd2),
+
+    {error, einval} = ?FILE_MODULE:advise(Fd2, 5, 5, normal),
+    {error, einval} = ?FILE_MODULE:allocate(Fd2, 5, 5),
+    {error, einval} = ?FILE_MODULE:close(Fd2),
+    {error, einval} = ?FILE_MODULE:datasync(Fd2),
+    {error, einval} = ?FILE_MODULE:position(Fd2, 5),
+    {error, einval} = ?FILE_MODULE:pread(Fd2, 5, 1),
+    {error, einval} = ?FILE_MODULE:pwrite(Fd2, 5, "einval please"),
+    {error, einval} = ?FILE_MODULE:read(Fd2, 1),
+    {error, einval} = ?FILE_MODULE:sync(Fd2),
+    {error, einval} = ?FILE_MODULE:truncate(Fd2),
+    {error, einval} = ?FILE_MODULE:write(Fd2, "einval please"),
+
     [] = flush(),
     ok.
 
@@ -1132,8 +1176,8 @@ pread_write_test(File, Data) ->
 	   end,
     I = Size + 17,
     ok = ?FILE_MODULE:pwrite(File, 0, Data),
-    Res = ?FILE_MODULE:pread(File, 0, I),
-    {ok, Data} = Res,
+    {ok, Data} = ?FILE_MODULE:pread(File, 0, I),
+    {ok, [Data]} = ?FILE_MODULE:pread(File, [{0, I}]),
     eof = ?FILE_MODULE:pread(File, I, 1),
     ok = ?FILE_MODULE:pwrite(File, [{0, Data}, {I, Data}]),
     {ok, [Data, eof, Data]} =
@@ -2044,13 +2088,22 @@ names(Config) when is_list(Config) ->
     ok = ?FILE_MODULE:close(Fd2),
     {ok,Fd3} = ?FILE_MODULE:open(Name3,read),
     ok = ?FILE_MODULE:close(Fd3),
+
+    %% Now try the same on raw files.
+    {ok,Fd4} = ?FILE_MODULE:open(Name2, [read, raw]),
+    ok = ?FILE_MODULE:close(Fd4),
+    {ok,Fd4f} = ?FILE_MODULE:open(lists:flatten(Name2), [read, raw]),
+    ok = ?FILE_MODULE:close(Fd4f),
+    {ok,Fd5} = ?FILE_MODULE:open(Name3, [read, raw]),
+    ok = ?FILE_MODULE:close(Fd5),
+
     case length(Name1) > 255 of
 	true ->
 	    io:format("Path too long for an atom:\n\n~p\n", [Name1]);
 	false ->
 	    Name4 = list_to_atom(Name1),
-	    {ok,Fd4} = ?FILE_MODULE:open(Name4,read),
-	    ok = ?FILE_MODULE:close(Fd4)
+	    {ok,Fd6} = ?FILE_MODULE:open(Name4,read),
+	    ok = ?FILE_MODULE:close(Fd6)
     end,
 
     %% Try some path names
@@ -2074,6 +2127,22 @@ names(Config) when is_list(Config) ->
     [] = flush(),
     ok.
 
+volume_relative_paths(Config) when is_list(Config) ->
+    case os:type() of
+        {win32, _} ->
+            {ok, [Drive, $: | _]} = file:get_cwd(),
+            %% Relative to current device root.
+            {ok, RootInfo} = file:read_file_info([Drive, $:, $/]),
+            {ok, RootInfo} = file:read_file_info("/"),
+            %% Relative to current device directory.
+            {ok, DirContents} = file:list_dir([Drive, $:]),
+            {ok, DirContents} = file:list_dir("."),
+            [] = flush(),
+            ok;
+        _ ->
+            {skip, "This test is Windows-specific."}
+    end.
+
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 
@@ -2641,8 +2710,8 @@ altname(Config) when is_list(Config) ->
 		{skipped, "Altname not supported on this platform"};
 	    {ok, "LONGAL~1"} -> 
 		{ok, "A_FILE~1"} = ?FILE_MODULE:altname(Name),
-		{ok, "C:/"} = ?FILE_MODULE:altname("C:/"),
-		{ok, "C:\\"} = ?FILE_MODULE:altname("C:\\"),
+		{ok, "c:/"} = ?FILE_MODULE:altname("C:/"),
+		{ok, "c:/"} = ?FILE_MODULE:altname("C:\\"),
 		{error,enoent} = ?FILE_MODULE:altname(NonexName),
 		{ok, "short"} = ?FILE_MODULE:altname(ShortName),
 		ok
@@ -2923,20 +2992,22 @@ delayed_write(Config) when is_list(Config) ->
     %%
     %% Test caching and normal close of non-raw file
     {ok, Fd1} = 
-	?FILE_MODULE:open(File, [write, {delayed_write, Size+1, 2000}]),
+	?FILE_MODULE:open(File, [write, {delayed_write, Size+1, 400}]),
     ok = ?FILE_MODULE:write(Fd1, Data1),
-    timer:sleep(1000), % Just in case the file system is slow
+    %% Wait for a reasonable amount of time to check whether the write was
+    %% practically instantaneous or actually delayed.
+    timer:sleep(100),
     {ok, Fd2} = ?FILE_MODULE:open(File, [read]),
     eof = ?FILE_MODULE:read(Fd2, 1),
     ok = ?FILE_MODULE:write(Fd1, Data1), % Data flush on size
-    timer:sleep(1000), % Just in case the file system is slow
+    timer:sleep(100),
     {ok, Data1Data1} = ?FILE_MODULE:pread(Fd2, bof, 2*Size+1),
     ok = ?FILE_MODULE:write(Fd1, Data1),
-    timer:sleep(3000), % Wait until data flush on timeout
+    timer:sleep(500), % Wait until data flush on timeout
     {ok, Data1Data1Data1} = ?FILE_MODULE:pread(Fd2, bof, 3*Size+1),
     ok = ?FILE_MODULE:write(Fd1, Data1),
     ok = ?FILE_MODULE:close(Fd1), % Data flush on close
-    timer:sleep(1000), % Just in case the file system is slow
+    timer:sleep(100),
     {ok, Data1Data1Data1Data1} = ?FILE_MODULE:pread(Fd2, bof, 4*Size+1),
     ok = ?FILE_MODULE:close(Fd2),
     %%
@@ -2970,7 +3041,7 @@ delayed_write(Config) when is_list(Config) ->
         {'DOWN', Mref1, _, _, _} = Down1a ->
             ct:fail(Down1a)
     end,
-    timer:sleep(1000), % Just in case the file system is slow
+    timer:sleep(100), % Just in case the file system is slow
     {ok, Fd3} = ?FILE_MODULE:open(File, [read]),
     eof = ?FILE_MODULE:read(Fd3, 1),
     Child1 ! {Parent, continue, normal},
@@ -2980,7 +3051,7 @@ delayed_write(Config) when is_list(Config) ->
         {'DOWN', Mref1, _, _, _} = Down1b ->
             ct:fail(Down1b)
     end,
-    timer:sleep(1000), % Just in case the file system is slow
+    timer:sleep(100), % Just in case the file system is slow
     {ok, Data1} = ?FILE_MODULE:pread(Fd3, bof, Size+1),
     ok = ?FILE_MODULE:close(Fd3),
     %%
@@ -2993,7 +3064,7 @@ delayed_write(Config) when is_list(Config) ->
         {'DOWN', Mref2, _, _, _} = Down2a ->
             ct:fail(Down2a)
     end,
-    timer:sleep(1000), % Just in case the file system is slow
+    timer:sleep(100), % Just in case the file system is slow
     {ok, Fd4} = ?FILE_MODULE:open(File, [read]),
     eof = ?FILE_MODULE:read(Fd4, 1),
     Child2 ! {Parent, continue, kill},
@@ -3003,7 +3074,7 @@ delayed_write(Config) when is_list(Config) ->
         {'DOWN', Mref2, _, _, _} = Down2b ->
             ct:fail(Down2b)
     end,
-    timer:sleep(1000), % Just in case the file system is slow
+    timer:sleep(100), % Just in case the file system is slow
     eof = ?FILE_MODULE:pread(Fd4, bof, 1),
     ok  = ?FILE_MODULE:close(Fd4),
     %%
@@ -3095,6 +3166,16 @@ read_ahead(Config) when is_list(Config) ->
     Data1Data2Data3 = Data1++Data2++Data3,
     {ok, Data1Data2Data3} = ?FILE_MODULE:read(Fd5, 3*Size+1),
     ok = ?FILE_MODULE:close(Fd5),
+
+    %% Ensure that a read that draws from both the buffer and the file won't
+    %% return anything wonky.
+    SplitData = << <<(I rem 256)>> || I <- lists:seq(1, 1024) >>,
+    file:write_file(File, SplitData),
+    {ok, Fd6} = ?FILE_MODULE:open(File, [raw, read, binary, {read_ahead, 256}]),
+    {ok, <<1>>} = file:read(Fd6, 1),
+    <<1, Shifted:512/binary, _Rest/binary>> = SplitData,
+    {ok, Shifted} = file:read(Fd6, 512),
+
     %%
     [] = flush(),
     ok.
@@ -3699,6 +3780,83 @@ do_large_write(Name) ->
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
+%% Benchmarks
+%%
+%% Note that we only measure the time it takes to run the isolated file
+%% operations and that the actual test runtime can differ significantly,
+%% especially on the write side as the files need to be truncated before
+%% writing.
+
+large_writes(Config) when is_list(Config) ->
+    Modes = [raw, binary],
+    OpCount = 4096,
+    Data = <<0:(64 bsl 10)/unit:8>>,
+    run_write_benchmark(Config, Modes, OpCount, Data).
+
+large_writes_delayed(Config) when is_list(Config) ->
+    %% Each write is exactly as large as the delay buffer, causing the writes
+    %% to pass through each time, giving us a decent idea of how much overhead
+    %% delayed_write adds.
+    Modes = [raw, binary, {delayed_write, 64 bsl 10, 2000}],
+    OpCount = 4096,
+    Data = <<0:(64 bsl 10)/unit:8>>,
+    run_write_benchmark(Config, Modes, OpCount, Data).
+
+tiny_writes(Config) when is_list(Config) ->
+    Modes = [raw, binary],
+    OpCount = 512 bsl 10,
+    Data = <<0>>,
+    run_write_benchmark(Config, Modes, OpCount, Data).
+
+tiny_writes_delayed(Config) when is_list(Config) ->
+    Modes = [raw, binary, {delayed_write, 512 bsl 10, 2000}],
+    OpCount = 512 bsl 10,
+    Data = <<0>>,
+    run_write_benchmark(Config, Modes, OpCount, Data).
+
+%% The read benchmarks assume that "benchmark_scratch_file" has been filled by
+%% the write benchmarks.
+
+tiny_reads(Config) when is_list(Config) ->
+    Modes = [raw, binary],
+    OpCount = 512 bsl 10,
+    run_read_benchmark(Config, Modes, OpCount, 1).
+
+tiny_reads_ahead(Config) when is_list(Config) ->
+    Modes = [raw, binary, {read_ahead, 512 bsl 10}],
+    OpCount = 512 bsl 10,
+    run_read_benchmark(Config, Modes, OpCount, 1).
+
+run_write_benchmark(Config, Modes, OpCount, Data) ->
+    run_benchmark(Config, [write | Modes], OpCount, fun file:write/2, Data).
+
+run_read_benchmark(Config, Modes, OpCount, OpSize) ->
+    run_benchmark(Config, [read | Modes], OpCount, fun file:read/2, OpSize).
+
+run_benchmark(Config, Modes, OpCount, Fun, Arg) ->
+    ScratchDir = proplists:get_value(priv_dir, Config),
+    Path = filename:join(ScratchDir, "benchmark_scratch_file"),
+    {ok, Fd} = file:open(Path, Modes),
+    submit_throughput_results(Fun, [Fd, Arg], OpCount).
+
+submit_throughput_results(Fun, Args, Times) ->
+    MSecs = measure_repeated_file_op(Fun, Args, Times, millisecond),
+    IOPS = trunc(Times * (1000 / MSecs)),
+    ct_event:notify(#event{ name = benchmark_data, data = [{value,IOPS}] }),
+    {comment, io_lib:format("~p IOPS, ~p ms", [IOPS, trunc(MSecs)])}.
+
+measure_repeated_file_op(Fun, Args, Times, Unit) ->
+    Start = os:perf_counter(Unit),
+    repeated_apply(Fun, Args, Times),
+    os:perf_counter(Unit) - Start.
+
+repeated_apply(_F, _Args, Times) when Times =< 0 ->
+    ok;
+repeated_apply(F, Args, Times) ->
+    erlang:apply(F, Args),
+    repeated_apply(F, Args, Times - 1).
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 
 response_analysis(Module, Function, Arguments) ->
@@ -3934,7 +4092,7 @@ read_line_create_files(TestData) ->
 read_line_remove_files(TestData) ->
     [ file:delete(File) || {_Function,File,_,_} <- TestData ].
 
-%% read_line with prim_file.
+%% read_line with ?PRIM_FILE.
 read_line_1(Config) when is_list(Config) ->
     PrivDir = proplists:get_value(priv_dir, Config),
     All = read_line_testdata(PrivDir),
@@ -4103,9 +4261,9 @@ read_line_create7(Filename) ->
     file:close(F).
 
 read_line_all(Filename) ->
-    {ok,F} = prim_file:open(Filename,[read,binary]),
+    {ok,F} = ?PRIM_FILE:open(Filename,[read,binary]),
     X=read_rl_lines(F),
-    prim_file:close(F),
+    ?PRIM_FILE:close(F),
     Bin = list_to_binary([B || {ok,B} <- X]),
     Bin = re:replace(list_to_binary([element(2,file:read_file(Filename))]),
 		     "\r\n","\n",[global,{return,binary}]),
@@ -4138,7 +4296,7 @@ read_line_all4(Filename) ->
     {length(X),Bin}.
 
 read_rl_lines(F) ->
-    case prim_file:read_line(F) of
+    case ?PRIM_FILE:read_line(F) of
 	eof ->
 	    [];
 	{error,X} ->
@@ -4158,9 +4316,9 @@ read_rl_lines2(F) ->
     end.
 
 read_line_all_alternating(Filename) ->
-    {ok,F} = prim_file:open(Filename,[read,binary]),
+    {ok,F} = ?PRIM_FILE:open(Filename,[read,binary]),
     X=read_rl_lines(F,true),
-    prim_file:close(F),
+    ?PRIM_FILE:close(F),
     Bin = list_to_binary([B || {ok,B} <- X]),
     Bin = re:replace(list_to_binary([element(2,file:read_file(Filename))]),
 		     "\r\n","\n",[global,{return,binary}]),
@@ -4194,8 +4352,8 @@ read_line_all_alternating4(Filename) ->
 read_rl_lines(F,Alternate) ->
     case begin
 	     case Alternate of
-		 true -> prim_file:read(F,1);
-		 false -> prim_file:read_line(F)
+		 true -> ?PRIM_FILE:read(F,1);
+		 false -> ?PRIM_FILE:read_line(F)
 	     end 
 	 end of
 	eof ->
diff --git a/lib/kernel/test/file_name_SUITE.erl b/lib/kernel/test/file_name_SUITE.erl
index 899102c908..3afc647081 100644
--- a/lib/kernel/test/file_name_SUITE.erl
+++ b/lib/kernel/test/file_name_SUITE.erl
@@ -77,6 +77,7 @@
 	 init_per_testcase/2, end_per_testcase/2]).
 -export([normal/1,icky/1,very_icky/1,normalize/1,home_dir/1]).
 
+-define(PRIM_FILE, prim_file).
 
 init_per_testcase(_Func, Config) ->
     Config.
@@ -131,7 +132,7 @@ home_dir(Config) when is_list(Config) ->
 					     os:putenv("HOME",NewHome),
 					     {"HOME",Save};
 					 _ ->
-					     rm_rf(prim_file,NewHome),
+					     rm_rf(?PRIM_FILE,NewHome),
 					     throw(unsupported_os)
 				     end,
 	try
@@ -145,7 +146,7 @@ home_dir(Config) when is_list(Config) ->
 		_ ->
 		    os:putenv(SaveOldName,SaveOldValue)
 	    end,
-	    rm_rf(prim_file,NewHome)
+	    rm_rf(?PRIM_FILE,NewHome)
 	end
     catch
 	throw:need_unicode_mode ->
@@ -190,7 +191,7 @@ normal(Config) when is_list(Config) ->
     try
 	Priv = proplists:get_value(priv_dir, Config),
 	file:set_cwd(Priv),
-	ok = check_normal(prim_file),
+	ok = check_normal(?PRIM_FILE),
 	ok = check_normal(file),
 	%% If all is good, delete dir again (avoid hanging dir on windows)
 	rm_rf(file,"normal_dir"),
@@ -210,7 +211,7 @@ icky(Config) when is_list(Config) ->
 	    try
 		Priv = proplists:get_value(priv_dir, Config),
 		file:set_cwd(Priv),
-		ok = check_icky(prim_file),
+		ok = check_icky(?PRIM_FILE),
 		ok = check_icky(file),
 		%% If all is good, delete dir again (avoid hanging dir on windows)
 		rm_rf(file,"icky_dir"),
@@ -229,7 +230,7 @@ very_icky(Config) when is_list(Config) ->
 	    try
 		Priv = proplists:get_value(priv_dir, Config),
 		file:set_cwd(Priv),
-		case check_very_icky(prim_file) of
+		case check_very_icky(?PRIM_FILE) of
 		    need_unicode_mode ->
 			{skipped,"VM needs to be started in Unicode filename mode"};
 		    ok ->
@@ -292,17 +293,14 @@ check_normal(Mod) ->
 		ok
 	end,
 	[ begin
-	      {ok, FD} = Mod:open(Name,[read]),
-	      {ok, Content} = Mod:read(FD,1024),
-	      ok = file:close(FD)
-	  end || {regular,Name,Content} <- NormalDir ],
-	[ begin
 	      {ok, FD} = Mod:open(Name,[read,binary]),
 	      BC = list_to_binary(Content),
 	      {ok, BC} = Mod:read(FD,1024),
 	      ok = file:close(FD)
 	  end || {regular,Name,Content} <- NormalDir ],
+	{error, badarg} = Mod:rename("fil1\0tmp_fil2","tmp_fil1"),
 	Mod:rename("fil1","tmp_fil1"),
+	{error, badarg} = Mod:read_file("tmp_fil1\0.txt"),
 	{ok, <<"fil1">>} = Mod:read_file("tmp_fil1"),
 	{error,enoent} = Mod:read_file("fil1"),
 	Mod:rename("tmp_fil1","fil1"),
@@ -410,11 +408,6 @@ check_icky(Mod) ->
 		ok
 	end,
 	[ begin
-	      {ok, FD} = Mod:open(Name,[read]),
-	      {ok, Content} = Mod:read(FD,1024),
-	      ok = file:close(FD)
-	  end || {regular,Name,Content} <- IckyDir ],
-	[ begin
 	      {ok, FD} = Mod:open(Name,[read,binary]),
 	      BC = list_to_binary([Content]),
 	      {ok, BC} = Mod:read(FD,1024),
@@ -519,11 +512,6 @@ check_very_icky(Mod) ->
 		ok
 	end,
 	[ begin
-	      {ok, FD} = Mod:open(Name,[read]),
-	      {ok, Content} = Mod:read(FD,1024),
-	      ok = file:close(FD)
-	  end || {regular,Name,Content} <- VeryIckyDir ],
-	[ begin
 	      {ok, FD} = Mod:open(Name,[read,binary]),
 	      BC = list_to_binary([Content]),
 	      {ok, BC} = Mod:read(FD,1024),
diff --git a/lib/kernel/test/gen_tcp_misc_SUITE.erl b/lib/kernel/test/gen_tcp_misc_SUITE.erl
index 331864b5de..e47023d201 100644
--- a/lib/kernel/test/gen_tcp_misc_SUITE.erl
+++ b/lib/kernel/test/gen_tcp_misc_SUITE.erl
@@ -1572,52 +1572,56 @@ fill_sendq(Config) when is_list(Config) ->
     Master = self(),
     Server =
 	spawn_link(fun () ->
-			   {ok,L} = gen_tcp:listen
-				      (0, [{active,false},binary,
-					   {reuseaddr,true},{packet,0}]),
+			   {ok,L} = gen_tcp:listen(0, [{active,false},binary,
+                                                       {reuseaddr,true},{packet,0}]),
 			   {ok,Port} = inet:port(L),
 			   Master ! {self(),client,
 				     fill_sendq_client(Port, Master)},
 			   fill_sendq_srv(L, Master)
 		   end),
     io:format("~p Server~n", [Server]),
-    receive {Server,client,Client} ->
-		  io:format("~p Client~n", [Client]),
-		  receive {Server,reader,Reader} ->
-				io:format("~p Reader~n", [Reader]),
-				fill_sendq_loop(Server, Client, Reader)
+    receive
+        {Server,client,Client} ->
+            io:format("~p Client~n", [Client]),
+            receive
+                {Server,reader,Reader} ->
+                    io:format("~p Reader~n", [Reader]),
+                    fill_sendq_loop(Server, Client, Reader)
 	    end
     end.
 
 fill_sendq_loop(Server, Client, Reader) ->
     %% Master
     %%
-    receive {Server,send} ->
+    receive
+        {Server,send} ->
 	    fill_sendq_loop(Server, Client, Reader)
     after 2000 ->
 	    %% Send queue full, sender blocked -> close client.
 	    io:format("Send timeout, closing Client...~n", []),
 	    Client ! {self(),close},
-	    receive {Server,[{error,closed}]} ->
-			  io:format("Got server closed.~n"),
-			  receive {Reader,[{error,closed}]} ->
-					io:format
-						("Got reader closed.~n"),
-					ok
-				after 3000 ->
-					ct:fail({timeout,{closed,reader}})
-				end;
-			  {Reader,[{error,closed}]} ->
-			  io:format("Got reader closed.~n"),
-			  receive {Server,[{error,closed}]} ->
-					io:format("Got server closed~n"),
-					ok
-				after 3000 ->
-					ct:fail({timeout,{closed,server}})
-				end
-		  after 3000 ->
-			  ct:fail({timeout,{closed,[server,reader]}})
-		  end
+	    receive
+                {Server,[{error,closed}]} ->
+                    io:format("Got server closed.~n"),
+                    receive
+                        {Reader,[{error,closed}]} ->
+                            io:format("Got reader closed.~n"),
+                            ok
+                    after 3000 ->
+                            ct:fail({timeout,{closed,reader}})
+                    end;
+                {Reader,[{error,closed}]} ->
+                    io:format("Got reader closed.~n"),
+                    receive
+                        {Server,[{error,closed}]} ->
+                            io:format("Got server closed~n"),
+                            ok
+                    after 3000 ->
+                            ct:fail({timeout,{closed,server}})
+                    end
+            after 3000 ->
+                    ct:fail({timeout,{closed,[server,reader]}})
+            end
     end.
 
 fill_sendq_srv(L, Master) ->
diff --git a/lib/kernel/test/gen_udp_SUITE.erl b/lib/kernel/test/gen_udp_SUITE.erl
index aa616d43d6..96e495505a 100644
--- a/lib/kernel/test/gen_udp_SUITE.erl
+++ b/lib/kernel/test/gen_udp_SUITE.erl
@@ -288,58 +288,56 @@ bad_address(Config) when is_list(Config) ->
 %%
 %% Starts a slave node that on command sends a bunch of messages
 %% to our UDP port. The receiving process just receives and
-%% ignores the incoming messages, but counts them.
-%% A tracing process traces the receiving process for
-%% 'receive' and scheduling events. From the trace, 
-%% message contents is verified; and, how many messages
-%% are received per in/out scheduling, which should be
-%% the same as the read_packets parameter.
-%% 
-%% What happens on the SMP emulator remains to be seen...
-%%
+%% ignores the incoming messages.
+%% A tracing process traces the receiving port for
+%% 'send' and scheduling events. From the trace,
+%% how many messages are received per in/out scheduling,
+%% which should never be more than the read_packet parameter.
 
 %% OTP-6249 UDP option for number of packet reads.
 read_packets(Config) when is_list(Config) ->
-    case erlang:system_info(smp_support) of
-	false ->
-	    read_packets_1();
-	true ->
-	    %% We would need some new sort of tracing to test this
-	    %% option reliably in an SMP emulator.
-	    {skip,"SMP emulator"}
-    end.
-
-read_packets_1() ->
     N1 = 5,
-    N2 = 7,
+    N2 = 1,
+    Msgs = 30000,
     {ok,R} = gen_udp:open(0, [{read_packets,N1}]),
     {ok,RP} = inet:port(R),
     {ok,Node} = start_node(gen_udp_SUITE_read_packets),
     Die = make_ref(),
-    Loop = erlang:spawn_link(fun () -> infinite_loop(Die) end),
     %%
-    Msgs1 = [erlang:integer_to_list(M) || M <- lists:seq(1, N1*3)],
-    [V1|_] = read_packets_test(R, RP, Msgs1, Node),
+    {V1, Trace1} = read_packets_test(R, RP, Msgs, Node),
     {ok,[{read_packets,N1}]} = inet:getopts(R, [read_packets]),
     %%
     ok = inet:setopts(R, [{read_packets,N2}]),
-    Msgs2 = [erlang:integer_to_list(M) || M <- lists:seq(1, N2*3)],
-    [V2|_] = read_packets_test(R, RP, Msgs2, Node),
+    {V2, Trace2} = read_packets_test(R, RP, Msgs, Node),
     {ok,[{read_packets,N2}]} = inet:getopts(R, [read_packets]),
     %%
     stop_node(Node),
-    Mref = erlang:monitor(process, Loop),
-    Loop ! Die,
-    receive
-	{'DOWN',Mref,_,_, normal} ->
-	    case {V1,V2} of
-		{N1,N2} ->
-		    ok;
-		_ when V1 =/= N1, V2 =/= N2 ->
-		    ok
-	    end
+    ct:log("N1=~p, V1=~p vs N2=~p, V2=~p",[N1,V1,N2,V2]),
+
+    dump_terms(Config, "trace1.terms", Trace2),
+    dump_terms(Config, "trace2.terms", Trace2),
+
+    %% Because of the inherit racy-ness of the feature it is
+    %% hard to test that it behaves correctly.
+    %% Right now (OTP 21) a port task takes 5% of the
+    %% allotted port task reductions to execute, so
+    %% the max number of executions a port is allowed to
+    %% do before being re-scheduled is N * 20
+
+    if
+        V1 > (N1 * 20) ->
+            ct:fail("Got ~p msgs, max was ~p", [V1, N1]);
+        V2 > (N2 * 20) ->
+            ct:fail("Got ~p msgs, max was ~p", [V2, N2]);
+        true ->
+            ok
     end.
 
+dump_terms(Config, Name, Terms) ->
+    FName = filename:join(proplists:get_value(priv_dir, Config),Name),
+    file:write_file(FName, term_to_binary(Terms)),
+    ct:log("Logged terms to ~s",[FName]).
+
 infinite_loop(Die) ->
     receive 
 	Die ->
@@ -350,7 +348,6 @@ infinite_loop(Die) ->
     end.
 
 read_packets_test(R, RP, Msgs, Node) ->
-    Len = length(Msgs),
     Receiver = self(),
     Tracer =
 	spawn_link(
@@ -375,24 +372,24 @@ read_packets_test(R, RP, Msgs, Node) ->
 	  [link,{priority,high}]),
     receive
 	{Sender,{port,SP}} ->
-	    erlang:trace(self(), true,
-			 [running,'receive',{tracer,Tracer}]),
+	    erlang:trace(R, true,
+			 [running_ports,'send',{tracer,Tracer}]),
 	    erlang:yield(),
 	    Sender ! {Receiver,go},
-	    read_packets_recv(Len),
-	    erlang:trace(self(), false, [all]),
+	    read_packets_recv(Msgs),
+	    erlang:trace(R, false, [all]),
 	    Tracer ! {Receiver,get_trace},
 	    receive
 		{Tracer,{trace,Trace}} ->
-		    read_packets_verify(R, SP, Msgs, Trace)
+		    {read_packets_verify(R, SP, Trace), Trace}
 	    end
     end.
 
-read_packets_send(S, RP, [Msg|Msgs]) ->
-    ok = gen_udp:send(S, localhost, RP, Msg),
-    read_packets_send(S, RP, Msgs);
-read_packets_send(_S, _RP, []) ->
-    ok.
+read_packets_send(_S, _RP, 0) ->
+    ok;
+read_packets_send(S, RP, Msgs) ->
+    ok = gen_udp:send(S, localhost, RP, "UDP FLOOOOOOD"),
+    read_packets_send(S, RP, Msgs - 1).
 
 read_packets_recv(0) ->
     ok;
@@ -404,23 +401,24 @@ read_packets_recv(N) ->
 	    timeout
     end.
 
-read_packets_verify(R, SP, Msg, Trace) ->    
-    lists:reverse(
-      lists:sort(read_packets_verify(R, SP, Msg, Trace, 0))).
-
-read_packets_verify(R, SP, Msgs, [{trace,Self,OutIn,_}|Trace], M) 
-  when Self =:= self(), OutIn =:= out;
-       Self =:= self(), OutIn =:= in ->
-    push(M, read_packets_verify(R, SP, Msgs, Trace, 0));
-read_packets_verify(R, SP, [Msg|Msgs],
-		    [{trace,Self,'receive',{udp,R,{127,0,0,1},SP,Msg}}
-		     |Trace], M)
+read_packets_verify(R, SP, Trace) ->
+    [Max | _] = Pkts = lists:reverse(lists:sort(read_packets_verify(R, SP, Trace, 0))),
+    ct:pal("~p",[lists:sublist(Pkts,10)]),
+    Max.
+
+read_packets_verify(R, SP, [{trace,R,OutIn,_}|Trace], M) 
+  when OutIn =:= out; OutIn =:= in ->
+    push(M, read_packets_verify(R, SP, Trace, 0));
+read_packets_verify(R, SP, [{trace, R,'receive',timeout}|Trace], M) ->
+    push(M, read_packets_verify(R, SP, Trace, 0));
+read_packets_verify(R, SP,
+		    [{trace,R,'send',{udp,R,{127,0,0,1},SP,_Msg}, Self} | Trace], M)
   when Self =:= self() ->
-    read_packets_verify(R, SP, Msgs, Trace, M+1);
-read_packets_verify(_R, _SP, [], [], M) ->
+    read_packets_verify(R, SP, Trace, M+1);
+read_packets_verify(_R, _SP, [], M) ->
     push(M, []);
-read_packets_verify(_R, _SP, Msgs, Trace, M) ->
-    ct:fail({read_packets_verify,mismatch,Msgs,Trace,M}).
+read_packets_verify(_R, _SP, Trace, M) ->
+    ct:fail({read_packets_verify,mismatch,Trace,M}).
 
 push(0, Vs) ->
     Vs;
diff --git a/lib/kernel/test/kernel_SUITE.erl b/lib/kernel/test/kernel_SUITE.erl
index da56359294..7898988dbe 100644
--- a/lib/kernel/test/kernel_SUITE.erl
+++ b/lib/kernel/test/kernel_SUITE.erl
@@ -30,14 +30,14 @@
 -export([init_per_testcase/2, end_per_testcase/2]).
 
 %% Test cases must be exported.
--export([app_test/1, appup_test/1]).
+-export([app_test/1, appup_test/1, refc/1]).
 
 suite() ->
     [{ct_hooks,[ts_install_cth]},
      {timetrap,{minutes,2}}].
 
 all() -> 
-    [app_test, appup_test].
+    [app_test, appup_test, refc].
 
 groups() -> 
     [].
@@ -163,3 +163,68 @@ check_appup([Vsn|Vsns],Instrs,Expected) ->
     end;
 check_appup([],_,_) ->
     ok.
+
+%%% Check that refc module handles the counters as expected
+refc(_Config) ->
+    Enable = fun(Enable) -> erlang:system_flag(scheduler_wall_time, Enable) end,
+    IsOn = fun() -> undefined /= erlang:statistics(scheduler_wall_time) end,
+    Tester = self(),
+    Loop = fun Loop() ->
+                   receive
+                       die -> normal;
+                       {apply, Bool} ->
+                           Res = Enable(Bool),
+                           Tester ! {self(), Res},
+                           Loop()
+                   end
+           end,
+
+    %% Counter should be 0
+    false = Enable(false),
+
+    false = Enable(true),
+    true  = Enable(true),
+    true  = Enable(false),
+    true  = Enable(false),
+
+    %% Counter should be 0
+    false = IsOn(),
+
+    P1 = spawn_link(Loop),
+    P1 ! {apply, true},
+    receive {P1, R1} -> false = R1 end,
+
+    %% P1 has turned it on counter should be one
+    true = IsOn(),
+    true = Enable(true),
+    true = Enable(false),
+    true = IsOn(),
+
+    P1 ! {apply, false},
+    receive {P1, R2} -> true = R2 end,
+    false = IsOn(),
+
+    P1 ! {apply, true},
+    receive {P1, R3} -> false = R3 end,
+    true = IsOn(),
+    true = Enable(false),
+
+
+    P1 ! die,
+    timer:sleep(100),
+    false = IsOn(),
+    false = Enable(false),
+
+    P2 = spawn_link(Loop),
+    P2 ! {apply, true},
+    receive {P2, R4} -> false = R4 end,
+    true = IsOn(),
+    P2 ! {apply, true},
+    receive {P2, R5} -> true = R5 end,
+    true = IsOn(),
+
+    P2 ! die,
+    timer:sleep(100),
+    false = IsOn(),
+
+    ok.
diff --git a/lib/kernel/test/kernel_bench.spec b/lib/kernel/test/kernel_bench.spec
index 8de60dae31..4de133f21b 100644
--- a/lib/kernel/test/kernel_bench.spec
+++ b/lib/kernel/test/kernel_bench.spec
@@ -1 +1,2 @@
 {groups,"../kernel_test",zlib_SUITE,[bench]}.
+{groups,"../kernel_test",file_SUITE,[bench]}.
diff --git a/lib/kernel/test/os_SUITE.erl b/lib/kernel/test/os_SUITE.erl
index 53a9e168ef..8056321448 100644
--- a/lib/kernel/test/os_SUITE.erl
+++ b/lib/kernel/test/os_SUITE.erl
@@ -22,7 +22,8 @@
 -export([all/0, suite/0,groups/0,init_per_suite/1, end_per_suite/1,
 	 init_per_group/2,end_per_group/2,
 	 init_per_testcase/2,end_per_testcase/2]).
--export([space_in_cwd/1, quoting/1, cmd_unicode/1, space_in_name/1, bad_command/1,
+-export([space_in_cwd/1, quoting/1, cmd_unicode/1, 
+         null_in_command/1, space_in_name/1, bad_command/1,
 	 find_executable/1, unix_comment_in_command/1, deep_list_command/1,
          large_output_command/1, background_command/0, background_command/1,
          message_leak/1, close_stdin/0, close_stdin/1, perf_counter_api/1]).
@@ -34,7 +35,8 @@ suite() ->
      {timetrap,{minutes,1}}].
 
 all() ->
-    [space_in_cwd, quoting, cmd_unicode, space_in_name, bad_command,
+    [space_in_cwd, quoting, cmd_unicode, null_in_command,
+     space_in_name, bad_command,
      find_executable, unix_comment_in_command, deep_list_command,
      large_output_command, background_command, message_leak,
      close_stdin, perf_counter_api].
@@ -125,6 +127,14 @@ cmd_unicode(Config) when is_list(Config) ->
     [] = receive_all(),
     ok.
 
+null_in_command(Config) ->
+    {Ok, Error} = case os:type() of
+                      {win32,_} -> {"dir", "di\0r"};
+                      _ -> {"ls", "l\0s"}
+                  end,
+    true = is_list(try os:cmd(Ok) catch Class0:_ -> Class0 end),
+    error = try os:cmd(Error) catch Class1:_ -> Class1 end,
+    ok.
 
 %% Test that program with a space in its name can be executed.
 space_in_name(Config) when is_list(Config) ->
diff --git a/lib/kernel/test/prim_file_SUITE.erl b/lib/kernel/test/prim_file_SUITE.erl
index 2f4330c217..db753679ea 100644
--- a/lib/kernel/test/prim_file_SUITE.erl
+++ b/lib/kernel/test/prim_file_SUITE.erl
@@ -21,38 +21,23 @@
 -export([all/0, suite/0,groups/0,init_per_suite/1, end_per_suite/1, 
 	 init_per_group/2,end_per_group/2, init_per_testcase/2, end_per_testcase/2,
 	 read_write_file/1, free_memory/0]).
--export([cur_dir_0a/1, cur_dir_0b/1, 
-	 cur_dir_1a/1, cur_dir_1b/1, 
-	 make_del_dir_a/1, make_del_dir_b/1,
-	 pos1/1, pos2/1]).
--export([close/1, 
-	 delete_a/1, delete_b/1]).
--export([ open1/1, modes/1]).
--export([ 
-	  file_info_basic_file_a/1, file_info_basic_file_b/1,
-	  file_info_basic_directory_a/1, file_info_basic_directory_b/1,
-	  file_info_bad_a/1, file_info_bad_b/1, 
-	  file_info_times_a/1, file_info_times_b/1, 
-	  file_write_file_info_a/1, file_write_file_info_b/1,
-	  file_read_file_info_opts/1, file_write_file_info_opts/1,
-	  file_write_read_file_info_opts/1
-	]).
--export([rename_a/1, rename_b/1, 
-	 access/1, truncate/1, datasync/1, sync/1,
+-export([cur_dir_0/1, cur_dir_1/1,
+	 make_del_dir/1, pos1/1, pos2/1]).
+-export([close/1, delete/1]).
+-export([open1/1, modes/1]).
+-export([file_info_basic_file/1, file_info_basic_directory/1, file_info_bad/1,
+	 file_info_times/1, file_write_file_info/1,
+         file_read_file_info_opts/1, file_write_file_info_opts/1,
+	 file_write_read_file_info_opts/1]).
+-export([rename/1, access/1, truncate/1, datasync/1, sync/1,
 	 read_write/1, pread_write/1, append/1, exclusive/1]).
--export([ e_delete/1, e_rename/1, e_make_dir/1, e_del_dir/1]).
+-export([e_delete/1, e_rename/1, e_make_dir/1, e_del_dir/1]).
 
--export([ read_not_really_compressed/1,
-	  read_compressed/1, write_compressed/1,
-	  compress_errors/1]).
-
--export([ 
-	  make_link_a/1, make_link_b/1,
-	  read_link_info_for_non_link/1, 
-	  symlinks_a/1, symlinks_b/1,
-	  list_dir_limit/1,
-	  list_dir_error/1,
-	  list_dir/1]).
+-export([make_link/1, read_link_info_for_non_link/1,
+	 symlinks/1,
+	 list_dir_limit/1,
+	 list_dir_error/1,
+	 list_dir/1]).
 
 -export([advise/1]).
 -export([large_write/1]).
@@ -67,29 +52,16 @@
 
 -define(PRIM_FILE, prim_file).
 
-%% Calls ?PRIM_FILE:F with arguments A and an optional handle H 
-%% as first argument, unless the handle is [], i.e no handle.
-%% This is a macro to give the compiler and thereby 
-%% the cross reference tool the possibility to interprete
-%% the call, since M, F, A (or [H | A]) can all be known at 
-%% compile time.
--define(PRIM_FILE_call(F, H, A), 
-	case H of
-	    [] -> apply(?PRIM_FILE, F, A);
-	    _ ->  apply(?PRIM_FILE, F, [H | A])
-	end).
-
 suite() -> [].
 
 all() -> 
     [read_write_file, {group, dirs}, {group, files},
-     delete_a, delete_b, rename_a, rename_b, {group, errors},
-     {group, compression}, {group, links}, list_dir_limit, list_dir].
+     delete, rename, {group, errors}, {group, links},
+     list_dir_limit, list_dir].
 
 groups() -> 
     [{dirs, [],
-      [make_del_dir_a, make_del_dir_b, cur_dir_0a, cur_dir_0b,
-       cur_dir_1a, cur_dir_1b]},
+      [make_del_dir, cur_dir_0, cur_dir_1]},
      {files, [],
       [{group, open}, {group, pos}, {group, file_info},
        truncate, sync, datasync, advise, large_write, allocate]},
@@ -98,22 +70,14 @@ groups() ->
        append, exclusive]},
      {pos, [], [pos1, pos2]},
      {file_info, [],
-      [file_info_basic_file_a, file_info_basic_file_b,
-       file_info_basic_directory_a,
-       file_info_basic_directory_b, file_info_bad_a,
-       file_info_bad_b, file_info_times_a, file_info_times_b,
-       file_write_file_info_a, file_write_file_info_b,
-       file_read_file_info_opts, file_write_file_info_opts,
-       file_write_read_file_info_opts
+      [file_info_basic_file,file_info_basic_directory, file_info_bad,
+       file_info_times, file_write_file_info, file_read_file_info_opts,
+       file_write_file_info_opts, file_write_read_file_info_opts
       ]},
      {errors, [],
       [e_delete, e_rename, e_make_dir, e_del_dir]},
-     {compression, [],
-      [read_compressed, read_not_really_compressed,
-       write_compressed, compress_errors]},
      {links, [],
-      [make_link_a, make_link_b, read_link_info_for_non_link,
-       symlinks_a, symlinks_b, list_dir_error]}].
+      [make_link, read_link_info_for_non_link, symlinks, list_dir_error]}].
 
 init_per_testcase(large_write, Config) ->
     {ok, Started} = application:ensure_all_started(os_mon),
@@ -246,39 +210,27 @@ read_write_file(Config) when is_list(Config) ->
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-
-make_del_dir_a(Config) when is_list(Config) ->
-    make_del_dir(Config, [], "_a").
-
-make_del_dir_b(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
-    Result = make_del_dir(Config, Handle, "_b"),
-    ok = ?PRIM_FILE:stop(Handle),
-    %% Just to make sure the state of the server makes a difference
-    {error, einval} = ?PRIM_FILE_call(get_cwd, Handle, []),
-    Result.
-
-make_del_dir(Config, Handle, Suffix) ->
+make_del_dir(Config) when is_list(Config) ->
     RootDir = proplists:get_value(priv_dir,Config),
     NewDir = filename:join(RootDir,
 			   atom_to_list(?MODULE)
-			   ++"_mk-dir"++Suffix),
-    ok = ?PRIM_FILE_call(make_dir, Handle, [NewDir]),
-    {error, eexist} = ?PRIM_FILE_call(make_dir, Handle, [NewDir]),
-    ok = ?PRIM_FILE_call(del_dir, Handle, [NewDir]),
-    {error, enoent} = ?PRIM_FILE_call(del_dir, Handle, [NewDir]),
+			   ++"_mk-dir"),
+    ok = ?PRIM_FILE:make_dir(NewDir),
+    {error, eexist} = ?PRIM_FILE:make_dir(NewDir),
+    ok = ?PRIM_FILE:del_dir(NewDir),
+    {error, enoent} = ?PRIM_FILE:del_dir(NewDir),
 
     %% Make sure we are not in a directory directly under test_server
     %% as that would result in eacces errors when trying to delete '..',
     %% because there are processes having that directory as current.
-    ok = ?PRIM_FILE_call(make_dir, Handle, [NewDir]),
-    {ok, CurrentDir} = ?PRIM_FILE_call(get_cwd, Handle, []),
+    ok = ?PRIM_FILE:make_dir(NewDir),
+    {ok, CurrentDir} = ?PRIM_FILE:get_cwd(),
     case {os:type(), length(NewDir) >= 260 } of
 	{{win32,_}, true} ->
 	    io:format("Skip set_cwd for windows path longer than 260 (MAX_PATH)\n", []),
 	    io:format("\nNewDir = ~p\n", [NewDir]);
 	_ ->
-	    ok = ?PRIM_FILE_call(set_cwd, Handle, [NewDir])
+	    ok = ?PRIM_FILE:set_cwd(NewDir)
     end,
     try
 	%% Check that we get an error when trying to create...
@@ -286,14 +238,14 @@ make_del_dir(Config, Handle, Suffix) ->
 	NewDir2 = filename:join(RootDir,
 				atom_to_list(?MODULE)
 				++"_mk-dir-noexist/foo"),
-	{error, enoent} = ?PRIM_FILE_call(make_dir, Handle, [NewDir2]),
+	{error, enoent} = ?PRIM_FILE:make_dir(NewDir2),
 	%% a nameless directory
-	{error, enoent} = ?PRIM_FILE_call(make_dir, Handle, [""]),
+	{error, enoent} = ?PRIM_FILE:make_dir(""),
 	%% a directory with illegal name
-	{error, badarg} = ?PRIM_FILE_call(make_dir, Handle, ['mk-dir']),
+	{error, badarg} = ?PRIM_FILE:make_dir('mk-dir'),
 
 	%% a directory with illegal name, even if it's a (bad) list
-	{error, badarg} = ?PRIM_FILE_call(make_dir, Handle, [[1,2,3,{}]]),
+	{error, badarg} = ?PRIM_FILE:make_dir([1,2,3,{}]),
 
 	%% Maybe this isn't an error, exactly, but worth mentioning anyway:
 	%% ok = ?PRIM_FILE:make_dir([$f,$o,$o,0,$b,$a,$r])),
@@ -306,125 +258,101 @@ make_del_dir(Config, Handle, Suffix) ->
 	%% Try deleting some bad directories
 	%% Deleting the parent directory to the current, sounds dangerous, huh?
 	%% Don't worry ;-) the parent directory should never be empty, right?
-	case ?PRIM_FILE_call(del_dir, Handle, [".."]) of
+	case ?PRIM_FILE:del_dir("..") of
 	    {error, eexist} -> ok;
 	    {error, eacces} -> ok;	%OpenBSD
 	    {error, einval} -> ok		%FreeBSD
 	end,
-	{error, enoent} = ?PRIM_FILE_call(del_dir, Handle, [""]),
-	{error, badarg} = ?PRIM_FILE_call(del_dir, Handle, [[3,2,1,{}]])
+	{error, enoent} = ?PRIM_FILE:del_dir(""),
+	{error, badarg} = ?PRIM_FILE:del_dir([3,2,1,{}])
     after
-	ok = ?PRIM_FILE_call(set_cwd, Handle, [CurrentDir])
+	ok = ?PRIM_FILE:set_cwd(CurrentDir)
     end,
     ok.
 
-cur_dir_0a(Config) when is_list(Config) ->
-    cur_dir_0(Config, []).
-
-cur_dir_0b(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
-    Result = cur_dir_0(Config, Handle),
-    ok = ?PRIM_FILE:stop(Handle),
-    Result.
-
-cur_dir_0(Config, Handle) ->
+cur_dir_0(Config) when is_list(Config) ->
     %% Find out the current dir, and cd to it ;-)
-    {ok,BaseDir} = ?PRIM_FILE_call(get_cwd, Handle, []),
+    {ok,BaseDir} = ?PRIM_FILE:get_cwd(),
     Dir1 = BaseDir ++ "", %% Check that it's a string
-    ok = ?PRIM_FILE_call(set_cwd, Handle, [Dir1]),
-    DirName = atom_to_list(?MODULE) ++
-	case Handle of
-	    [] ->
-		"_curdir";
-	    _ ->
-		"_curdir_h"
-	end,
+    ok = ?PRIM_FILE:set_cwd(Dir1),
+    DirName = atom_to_list(?MODULE) ++ "_curdir",
 
     %% Make a new dir, and cd to that
     RootDir = proplists:get_value(priv_dir,Config),
     NewDir = filename:join(RootDir, DirName),
-    ok = ?PRIM_FILE_call(make_dir, Handle, [NewDir]),
+    ok = ?PRIM_FILE:make_dir(NewDir),
     case {os:type(), length(NewDir) >= 260} of
 	{{win32,_}, true} ->
 	    io:format("Skip set_cwd for windows path longer than 260 (MAX_PATH):\n"),
 	    io:format("\nNewDir = ~p\n", [NewDir]);
 	_ ->
 	    io:format("cd to ~s",[NewDir]),
-	    ok = ?PRIM_FILE_call(set_cwd, Handle, [NewDir]),
+	    ok = ?PRIM_FILE:set_cwd(NewDir),
 
 	    %% Create a file in the new current directory, and check that it
 	    %% really is created there
 	    UncommonName = "uncommon.fil",
 	    {ok,Fd} = ?PRIM_FILE:open(UncommonName, [read, write]),
 	    ok = ?PRIM_FILE:close(Fd),
-	    {ok,NewDirFiles} = ?PRIM_FILE_call(list_dir, Handle, ["."]),
+	    {ok,NewDirFiles} = ?PRIM_FILE:list_dir("."),
 	    true = lists:member(UncommonName,NewDirFiles),
 
 	    %% Delete the directory and return to the old current directory
 	    %% and check that the created file isn't there (too!)
 	    expect({error, einval}, {error, eacces}, {error, eexist},
-		   ?PRIM_FILE_call(del_dir, Handle, [NewDir])),
-	    ?PRIM_FILE_call(delete, Handle, [UncommonName]),
-	    {ok,[]} = ?PRIM_FILE_call(list_dir, Handle, ["."]),
-	    ok = ?PRIM_FILE_call(set_cwd, Handle, [Dir1]),
+		   ?PRIM_FILE:del_dir(NewDir)),
+	    ?PRIM_FILE:delete(UncommonName),
+	    {ok,[]} = ?PRIM_FILE:list_dir("."),
+	    ok = ?PRIM_FILE:set_cwd(Dir1),
 	    io:format("cd back to ~s",[Dir1]),
-	    ok = ?PRIM_FILE_call(del_dir, Handle, [NewDir]),
-	    {error, enoent} = ?PRIM_FILE_call(set_cwd, Handle, [NewDir]),
-	    ok = ?PRIM_FILE_call(set_cwd, Handle, [Dir1]),
+	    ok = ?PRIM_FILE:del_dir(NewDir),
+	    {error, enoent} = ?PRIM_FILE:set_cwd(NewDir),
+	    ok = ?PRIM_FILE:set_cwd(Dir1),
 	    io:format("cd back to ~s",[Dir1]),
-	    {ok,OldDirFiles} = ?PRIM_FILE_call(list_dir, Handle, ["."]),
+	    {ok,OldDirFiles} = ?PRIM_FILE:list_dir("."),
 	    false = lists:member(UncommonName,OldDirFiles)
     end,
 
     %% Try doing some bad things
     {error, badarg} =
-	?PRIM_FILE_call(set_cwd, Handle, [{foo,bar}]),
+	?PRIM_FILE:set_cwd({foo,bar}),
     {error, enoent} =
-	?PRIM_FILE_call(set_cwd, Handle, [""]),
+	?PRIM_FILE:set_cwd(""),
     {error, enoent} =
-	?PRIM_FILE_call(set_cwd, Handle, [".......a......"]),
+	?PRIM_FILE:set_cwd(".......a......"),
     {ok,BaseDir} =
-	?PRIM_FILE_call(get_cwd, Handle, []), %% Still there?
+	?PRIM_FILE:get_cwd(), %% Still there?
 
     %% On Windows, there should only be slashes, no backslashes,
     %% in the return value of get_cwd().
     %% (The test is harmless on Unix, because filenames usually
     %% don't contain backslashes.)
 
-    {ok, BaseDir} = ?PRIM_FILE_call(get_cwd, Handle, []),
+    {ok, BaseDir} = ?PRIM_FILE:get_cwd(),
     false = lists:member($\\, BaseDir),
 
     ok.
 
 %% Tests ?PRIM_FILE:get_cwd/1.
 
-cur_dir_1a(Config) when is_list(Config) ->
-    cur_dir_1(Config, []).
-
-cur_dir_1b(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
-    Result = cur_dir_1(Config, Handle),
-    ok = ?PRIM_FILE:stop(Handle),
-    Result.
-
-cur_dir_1(Config, Handle) ->
+cur_dir_1(Config) when is_list(Config) ->
     case os:type() of
 	{win32, _} ->
-	    win_cur_dir_1(Config, Handle);
+	    win_cur_dir_1(Config);
 	_ ->
 	    {error, enotsup} =
-		?PRIM_FILE_call(get_cwd, Handle, ["d:"])
+		?PRIM_FILE:get_cwd("d:")
     end,
     ok.
 
-win_cur_dir_1(_Config, Handle) ->
-    {ok, BaseDir} = ?PRIM_FILE_call(get_cwd, Handle, []),
+win_cur_dir_1(_Config) ->
+    {ok, BaseDir} = ?PRIM_FILE:get_cwd(),
 
     %% Get the drive letter from the current directory,
     %% and try to get current directory for that drive.
 
     [Drive, $:|_] = BaseDir,
-    {ok, BaseDir} = ?PRIM_FILE_call(get_cwd, Handle, [[Drive, $:]]),
+    {ok, BaseDir} = ?PRIM_FILE:get_cwd([Drive, $:]),
     io:format("BaseDir = ~s\n", [BaseDir]),
 
     %% Unfortunately, there is no way to move away from the
@@ -446,12 +374,12 @@ open1(Config) when is_list(Config) ->
     Name = filename:join(NewDir, "foo1.fil"),
     {ok,Fd1} = ?PRIM_FILE:open(Name, [read, write]),
     {ok,Fd2} = ?PRIM_FILE:open(Name, [read]),
-    Str = "{a,tuple}.\n",
-    Length = length(Str),
-    ?PRIM_FILE:write(Fd1,Str),
+    Bin = list_to_binary("{a,tuple}.\n"),
+    Length = byte_size(Bin),
+    ?PRIM_FILE:write(Fd1,Bin),
     {ok,0} = ?PRIM_FILE:position(Fd1,bof),
-    {ok, Str} = ?PRIM_FILE:read(Fd1,Length),
-    {ok, Str} = ?PRIM_FILE:read(Fd2,Length),
+    {ok, Bin} = ?PRIM_FILE:read(Fd1,Length),
+    {ok, Bin} = ?PRIM_FILE:read(Fd2,Length),
     ok = ?PRIM_FILE:close(Fd2),
     {ok,0} = ?PRIM_FILE:position(Fd1,bof),
     ok = ?PRIM_FILE:truncate(Fd1),
@@ -471,13 +399,13 @@ modes(Config) when is_list(Config) ->
 			   ++"_open_modes"),
     ok = ?PRIM_FILE:make_dir(NewDir),
     Name1 = filename:join(NewDir, "foo1.fil"),
-    Marker = "hello, world",
-    Length = length(Marker),
+    Marker = <<"hello, world">>,
+    Length = byte_size(Marker),
 
     %% write
     {ok, Fd1} = ?PRIM_FILE:open(Name1, [write]),
     ok = ?PRIM_FILE:write(Fd1, Marker),
-    ok = ?PRIM_FILE:write(Fd1, ".\n"),
+    ok = ?PRIM_FILE:write(Fd1, <<".\n">>),
     ok = ?PRIM_FILE:close(Fd1),
 
     %% read
@@ -496,12 +424,6 @@ modes(Config) when is_list(Config) ->
     {ok, Marker} = ?PRIM_FILE:read(Fd4, Length),
     ok = ?PRIM_FILE:close(Fd4),
 
-    %% read and binary
-    BinaryMarker = list_to_binary(Marker),
-    {ok, Fd5} = ?PRIM_FILE:open(Name1, [read, binary]),
-    {ok, BinaryMarker} = ?PRIM_FILE:read(Fd5, Length),
-    ok = ?PRIM_FILE:close(Fd5),
-
     ok.
 
 close(Config) when is_list(Config) ->
@@ -528,9 +450,9 @@ access(Config) when is_list(Config) ->
     Name = filename:join(RootDir,
 			 atom_to_list(?MODULE)
 			 ++"_access.fil"),
-    Str = "ABCDEFGH",
+    Bin = <<"ABCDEFGH">>,
     {ok,Fd1} = ?PRIM_FILE:open(Name, [write]),
-    ?PRIM_FILE:write(Fd1,Str),
+    ?PRIM_FILE:write(Fd1,Bin),
     ok = ?PRIM_FILE:close(Fd1),
     %% Check that we can't write when in read only mode
     {ok,Fd2} = ?PRIM_FILE:open(Name, [read]),
@@ -542,7 +464,7 @@ access(Config) when is_list(Config) ->
     end,
     ok = ?PRIM_FILE:close(Fd2),
     {ok, Fd3} = ?PRIM_FILE:open(Name, [read]),
-    {ok, Str} = ?PRIM_FILE:read(Fd3,length(Str)),
+    {ok, Bin} = ?PRIM_FILE:read(Fd3,byte_size(Bin)),
     ok = ?PRIM_FILE:close(Fd3),
 
     ok.
@@ -564,7 +486,7 @@ read_write(Config) when is_list(Config) ->
     ok.
 
 read_write_test(File) ->
-    Marker = "hello, world",
+    Marker = <<"hello, world">>,
     ok = ?PRIM_FILE:write(File, Marker),
     {ok, 0} = ?PRIM_FILE:position(File, 0),
     {ok, Marker} = ?PRIM_FILE:read(File, 100),
@@ -590,15 +512,15 @@ pread_write(Config) when is_list(Config) ->
     ok.
 
 pread_write_test(File) ->
-    Marker = "hello, world",
-    Len = length(Marker),
+    Marker = <<"hello, world">>,
+    Len = byte_size(Marker),
     ok = ?PRIM_FILE:write(File, Marker),
     {ok, Marker} = ?PRIM_FILE:pread(File, 0, 100),
     eof = ?PRIM_FILE:pread(File, 100, 1),
     ok = ?PRIM_FILE:pwrite(File, Len, Marker),
     {ok, Marker} = ?PRIM_FILE:pread(File, Len, 100),
     eof = ?PRIM_FILE:pread(File, 100, 1),
-    MM = Marker ++ Marker,
+    MM = <<Marker/binary,Marker/binary>>,
     {ok, MM} = ?PRIM_FILE:pread(File, 0, 100),
     ok = ?PRIM_FILE:close(File),
     ok.
@@ -655,24 +577,24 @@ pos1(Config) when is_list(Config) ->
 			 atom_to_list(?MODULE)
 			 ++"_pos1.fil"),
     {ok, Fd1} = ?PRIM_FILE:open(Name, [write]),
-    ?PRIM_FILE:write(Fd1,"ABCDEFGH"),
+    ?PRIM_FILE:write(Fd1,<<"ABCDEFGH">>),
     ok        = ?PRIM_FILE:close(Fd1),
     {ok, Fd2} = ?PRIM_FILE:open(Name, [read]),
 
     %% Start pos is first char
     io:format("Relative positions"),
-    {ok, "A"} = ?PRIM_FILE:read(Fd2,1),
+    {ok, <<"A">>} = ?PRIM_FILE:read(Fd2,1),
     {ok, 2}   = ?PRIM_FILE:position(Fd2,{cur,1}),
-    {ok, "C"} = ?PRIM_FILE:read(Fd2,1),
+    {ok, <<"C">>} = ?PRIM_FILE:read(Fd2,1),
     {ok, 0}   = ?PRIM_FILE:position(Fd2,{cur,-3}),
-    {ok, "A"} = ?PRIM_FILE:read(Fd2,1),
+    {ok, <<"A">>} = ?PRIM_FILE:read(Fd2,1),
     %% Backwards from first char should be an error
     {ok,0}    = ?PRIM_FILE:position(Fd2,{cur,-1}),
     {error, einval} = ?PRIM_FILE:position(Fd2,{cur,-1}),
     %% Reset position and move again
     {ok, 0}   = ?PRIM_FILE:position(Fd2,0),
     {ok, 2}   = ?PRIM_FILE:position(Fd2,{cur,2}),
-    {ok, "C"} = ?PRIM_FILE:read(Fd2,1),
+    {ok, <<"C">>} = ?PRIM_FILE:read(Fd2,1),
     %% Go a lot forwards
     {ok, 13}  = ?PRIM_FILE:position(Fd2,{cur,10}),
     eof       = ?PRIM_FILE:read(Fd2,1),
@@ -684,27 +606,27 @@ pos1(Config) when is_list(Config) ->
     {ok, 8}   = ?PRIM_FILE:position(Fd2,cur),
     eof = ?PRIM_FILE:read(Fd2,1),
     {ok, 7}   = ?PRIM_FILE:position(Fd2,7),
-    {ok, "H"} = ?PRIM_FILE:read(Fd2,1),
+    {ok, <<"H">>} = ?PRIM_FILE:read(Fd2,1),
     {ok, 0}   = ?PRIM_FILE:position(Fd2,0),
-    {ok, "A"} = ?PRIM_FILE:read(Fd2,1),
+    {ok, <<"A">>} = ?PRIM_FILE:read(Fd2,1),
     {ok, 3}   = ?PRIM_FILE:position(Fd2,3),
-    {ok, "D"} = ?PRIM_FILE:read(Fd2,1),
+    {ok, <<"D">>} = ?PRIM_FILE:read(Fd2,1),
     {ok, 12}  = ?PRIM_FILE:position(Fd2,12),
     eof       = ?PRIM_FILE:read(Fd2,1),
     {ok, 3}   = ?PRIM_FILE:position(Fd2,3),
-    {ok, "D"} = ?PRIM_FILE:read(Fd2,1),
+    {ok, <<"D">>} = ?PRIM_FILE:read(Fd2,1),
     %% Try the {bof,X} notation
     {ok, 3}   = ?PRIM_FILE:position(Fd2,{bof,3}),
-    {ok, "D"} = ?PRIM_FILE:read(Fd2,1),
+    {ok, <<"D">>} = ?PRIM_FILE:read(Fd2,1),
 
     %% Try eof positions
     io:format("EOF positions"),
     {ok, 8}   = ?PRIM_FILE:position(Fd2,{eof,0}),
     eof       = ?PRIM_FILE:read(Fd2,1),
     {ok, 7}   = ?PRIM_FILE:position(Fd2,{eof,-1}),
-    {ok, "H"} = ?PRIM_FILE:read(Fd2,1),
+    {ok, <<"H">>} = ?PRIM_FILE:read(Fd2,1),
     {ok, 0}   = ?PRIM_FILE:position(Fd2,{eof,-8}),
-    {ok, "A"} = ?PRIM_FILE:read(Fd2,1),
+    {ok, <<"A">>} = ?PRIM_FILE:read(Fd2,1),
     {error, einval} = ?PRIM_FILE:position(Fd2,{eof,-9}),
     ok.
 
@@ -714,7 +636,7 @@ pos2(Config) when is_list(Config) ->
 			 atom_to_list(?MODULE)
 			 ++"_pos2.fil"),
     {ok,Fd1} = ?PRIM_FILE:open(Name, [write]),
-    ?PRIM_FILE:write(Fd1,"ABCDEFGH"),
+    ?PRIM_FILE:write(Fd1,<<"ABCDEFGH">>),
     ok = ?PRIM_FILE:close(Fd1),
     {ok, Fd2} = ?PRIM_FILE:open(Name, [read]),
     {error, einval} = ?PRIM_FILE:position(Fd2,-1),
@@ -722,35 +644,25 @@ pos2(Config) when is_list(Config) ->
     %% Make sure that we still can search after an error.
     {ok, 0}   = ?PRIM_FILE:position(Fd2, 0),
     {ok, 3}   = ?PRIM_FILE:position(Fd2, {bof,3}),
-    {ok, "D"} = ?PRIM_FILE:read(Fd2,1),
+    {ok, <<"D">>} = ?PRIM_FILE:read(Fd2,1),
 
     io:format("DONE"),
     ok.
 
-
-file_info_basic_file_a(Config) when is_list(Config) ->
-    file_info_basic_file(Config, [], "_a").
-
-file_info_basic_file_b(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
-    Result = file_info_basic_file(Config, Handle, "_b"),
-    ok = ?PRIM_FILE:stop(Handle),
-    Result.
-
-file_info_basic_file(Config, Handle, Suffix) ->
+file_info_basic_file(Config) when is_list(Config) ->
     RootDir = proplists:get_value(priv_dir, Config),
 
     %% Create a short file.
     Name = filename:join(RootDir,
 			 atom_to_list(?MODULE)
-			 ++"_basic_test"++Suffix++".fil"),
+			 ++"_basic_test"".fil"),
     {ok,Fd1} = ?PRIM_FILE:open(Name, [write]),
     ?PRIM_FILE:write(Fd1, "foo bar"),
     ok = ?PRIM_FILE:close(Fd1),
 
     %% Test that the file has the expected attributes.
     %% The times are tricky, so we will save them to a separate test case.
-    {ok, FileInfo} = ?PRIM_FILE_call(read_file_info, Handle, [Name]),
+    {ok, FileInfo} = ?PRIM_FILE:read_file_info(Name),
     #file_info{size = Size, type = Type, access = Access,
 	       atime = AccessTime, mtime = ModifyTime} =
 	FileInfo,
@@ -768,39 +680,30 @@ file_info_basic_file(Config, Handle, Suffix) ->
 
     ok.
 
-file_info_basic_directory_a(Config) when is_list(Config) ->
-    file_info_basic_directory(Config, []).
-
-file_info_basic_directory_b(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
-    Result = file_info_basic_directory(Config, Handle),
-    ok = ?PRIM_FILE:stop(Handle),
-    Result.
-
-file_info_basic_directory(Config, Handle) ->
+file_info_basic_directory(Config) when is_list(Config) ->
     %% Note: filename:join/1 removes any trailing slash,
     %% which is essential for ?PRIM_FILE:read_file_info/1 to work on
     %% platforms such as Windows95.
     RootDir = filename:join([proplists:get_value(priv_dir, Config)]),
 
     %% Test that the RootDir directory has the expected attributes.
-    test_directory(RootDir, read_write, Handle),
+    test_directory(RootDir, read_write),
 
     %% Note that on Windows file systems, "/" or "c:/" are *NOT* directories.
     %% Therefore, test that ?PRIM_FILE:read_file_info/1 behaves 
     %% as if they were directories.
     case os:type() of
 	{win32, _} ->
-	    test_directory("/", read_write, Handle),
-	    test_directory("c:/", read_write, Handle),
-	    test_directory("c:\\", read_write, Handle);
+	    test_directory("/", read_write),
+	    test_directory("c:/", read_write),
+	    test_directory("c:\\", read_write);
 	_ ->
-	    test_directory("/", read, Handle)
+	    test_directory("/", read)
     end,
     ok.
 
-test_directory(Name, ExpectedAccess, Handle) ->
-    {ok, FileInfo} = ?PRIM_FILE_call(read_file_info, Handle, [Name]),
+test_directory(Name, ExpectedAccess) ->
+    {ok, FileInfo} = ?PRIM_FILE:read_file_info(Name),
     #file_info{size = Size, type = Type, access = Access,
 	       atime = AccessTime, mtime = ModifyTime} =
 	FileInfo,
@@ -824,45 +727,24 @@ all_integers([]) ->
 
 %% Try something nonexistent.
 
-file_info_bad_a(Config) when is_list(Config) ->
-    file_info_bad(Config, []).
-
-file_info_bad_b(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
-    Result = file_info_bad(Config, Handle),
-    ok = ?PRIM_FILE:stop(Handle),
-    Result.
-
-file_info_bad(Config, Handle) ->
+file_info_bad(Config) when is_list(Config) ->
     RootDir = filename:join([proplists:get_value(priv_dir, Config)]),
-    {error, enoent} =
-	?PRIM_FILE_call(
-	   read_file_info, Handle, 
-	   [filename:join(RootDir,
-			  atom_to_list(?MODULE)++"_nonexistent")]),
+    NonExistent = filename:join(RootDir, atom_to_list(?MODULE)++"_nonexistent"),
+    {error, enoent} = ?PRIM_FILE:read_file_info(NonExistent),
     ok.
 
 %% Test that the file times behave as they should.
 
-file_info_times_a(Config) when is_list(Config) ->
-    file_info_times(Config, [], "_a").
-
-file_info_times_b(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
-    Result = file_info_times(Config, Handle, "_b"),
-    ok = ?PRIM_FILE:stop(Handle),
-    Result.
-
-file_info_times(Config, Handle, Suffix) ->
+file_info_times(Config) when is_list(Config) ->
     %% We have to try this twice, since if the test runs across the change
     %% of a month the time diff calculations will fail. But it won't happen
     %% if you run it twice in succession.
     test_server:m_out_of_n(
       1,2,
-      fun() -> file_info_int(Config, Handle, Suffix) end),
+      fun() -> file_info_int(Config) end),
     ok.
 
-file_info_int(Config, Handle, Suffix) ->
+file_info_int(Config) ->
     %% Note: filename:join/1 removes any trailing slash,
     %% which is essential for ?PRIM_FILE:read_file_info/1 to work on
     %% platforms such as Windows95.
@@ -872,14 +754,14 @@ file_info_int(Config, Handle, Suffix) ->
 
     Name = filename:join(RootDir,
 			 atom_to_list(?MODULE)
-			 ++"_file_info"++Suffix++".fil"),
+			 ++"_file_info.fil"),
     {ok,Fd1} = ?PRIM_FILE:open(Name, [write]),
     ?PRIM_FILE:write(Fd1,"foo"),
 
     %% check that the file got a modify date max a few seconds away from now
     {ok, #file_info{type = regular,
 		    atime = AccTime1, mtime = ModTime1}} =
-	?PRIM_FILE_call(read_file_info, Handle, [Name]),
+	?PRIM_FILE:read_file_info(Name),
     Now = erlang:localtime(),
     io:format("Now ~p",[Now]),
     io:format("Open file Acc ~p Mod ~p",[AccTime1,ModTime1]),
@@ -897,7 +779,7 @@ file_info_int(Config, Handle, Suffix) ->
     ok = ?PRIM_FILE:close(Fd1),
     {ok, #file_info{size = Size, type = regular, access = Access,
 		    atime = AccTime2, mtime = ModTime2}} =
-	?PRIM_FILE_call(read_file_info, Handle, [Name]),
+	?PRIM_FILE:read_file_info(Name),
     io:format("Closed file Acc ~p Mod ~p",[AccTime2,ModTime2]),
     true = time_dist(ModTime1, ModTime2) >= 0,
 
@@ -909,7 +791,7 @@ file_info_int(Config, Handle, Suffix) ->
     {ok, #file_info{size = DSize, type = directory,
 		    access = DAccess,
 		    atime = AccTime3, mtime = ModTime3}} =
-	?PRIM_FILE_call(read_file_info, Handle, [RootDir]),
+	?PRIM_FILE:read_file_info(RootDir),
     %% this dir was modified only a few secs ago
     io:format("Dir Acc ~p; Mod ~p; Now ~p",
 	      [AccTime3, ModTime3, Now]),
@@ -936,16 +818,7 @@ filter_atime(Atime, Config) ->
 
 %% Test the write_file_info/2 function.
 
-file_write_file_info_a(Config) when is_list(Config) ->
-    file_write_file_info(Config, [], "_a").
-
-file_write_file_info_b(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
-    Result = file_write_file_info(Config, Handle, "_b"),
-    ok = ?PRIM_FILE:stop(Handle),
-    Result.
-
-file_write_file_info(Config, Handle, Suffix) ->
+file_write_file_info(Config) when is_list(Config) ->
     RootDir = get_good_directory(Config),
     io:format("RootDir = ~p", [RootDir]),
 
@@ -955,16 +828,16 @@ file_write_file_info(Config, Handle, Suffix) ->
 
     Name = filename:join(RootDir,
 			 atom_to_list(?MODULE)
-			 ++"_write_file_info_ro"++Suffix),
+			 ++"_write_file_info_ro"),
     ok = ?PRIM_FILE:write_file(Name, "hello"),
     Time = {{1997, 01, 02}, {12, 35, 42}},
     Info = #file_info{mode=8#400, atime=Time, mtime=Time, ctime=Time},
-    ok = ?PRIM_FILE_call(write_file_info, Handle, [Name, Info]),
+    ok = ?PRIM_FILE:write_file_info(Name, Info),
 
     %% Read back the times.
 
     {ok, ActualInfo} =
-	?PRIM_FILE_call(read_file_info, Handle, [Name]),
+	?PRIM_FILE:read_file_info(Name),
     #file_info{mode=_Mode, atime=ActAtime, mtime=Time,
 	       ctime=ActCtime} = ActualInfo,
     FilteredAtime = filter_atime(Time, Config),
@@ -980,14 +853,11 @@ file_write_file_info(Config, Handle, Suffix) ->
     {error, eacces} = ?PRIM_FILE:write_file(Name, "hello again"),
 
     %% Make the file writable again.
-
-    ?PRIM_FILE_call(write_file_info, Handle,
-		    [Name, #file_info{mode=8#600}]),
+    ?PRIM_FILE:write_file_info(Name, #file_info{mode=8#600}),
     ok = ?PRIM_FILE:write_file(Name, "hello again"),
 
     %% And unwritable.
-    ?PRIM_FILE_call(write_file_info, Handle,
-		    [Name, #file_info{mode=8#400}]),
+    ?PRIM_FILE:write_file_info(Name, #file_info{mode=8#400}),
     {error, eacces} = ?PRIM_FILE:write_file(Name, "hello again"),
 
     %% Write the times again.
@@ -995,9 +865,9 @@ file_write_file_info(Config, Handle, Suffix) ->
 
     NewTime = {{1997, 02, 15}, {13, 18, 20}},
     NewInfo = #file_info{atime=NewTime, mtime=NewTime, ctime=NewTime},
-    ok = ?PRIM_FILE_call(write_file_info, Handle, [Name, NewInfo]),
+    ok = ?PRIM_FILE:write_file_info(Name, NewInfo),
     {ok, ActualInfo2} =
-	?PRIM_FILE_call(read_file_info, Handle, [Name]),
+	?PRIM_FILE:read_file_info(Name),
     #file_info{atime=NewActAtime, mtime=NewTime,
 	       ctime=NewActCtime} = ActualInfo2,
     NewFilteredAtime = filter_atime(NewTime, Config),
@@ -1012,14 +882,12 @@ file_write_file_info(Config, Handle, Suffix) ->
 
     %% Make the file writeable again, so that we can remove the
     %% test suites ... :-)
-    ?PRIM_FILE_call(write_file_info, Handle,
-		    [Name, #file_info{mode=8#600}]),
+    ?PRIM_FILE:write_file_info(Name, #file_info{mode=8#600}),
     ok.
 
 %% Test the write_file_info/3 function.
 
 file_write_file_info_opts(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
     RootDir = get_good_directory(Config),
     io:format("RootDir = ~p", [RootDir]),
 
@@ -1028,7 +896,7 @@ file_write_file_info_opts(Config) when is_list(Config) ->
 
     lists:foreach(fun
 		      ({FI, Opts}) ->
-			 ok = ?PRIM_FILE_call(write_file_info, Handle, [Name, FI, Opts])
+			 ok = ?PRIM_FILE:write_file_info(Name, FI, Opts)
 		 end, [
 			{#file_info{ mode=8#600, atime = Time, mtime = Time, ctime = Time}, Opts} ||
 			  Opts <- [[{time, posix}]],
@@ -1038,7 +906,7 @@ file_write_file_info_opts(Config) when is_list(Config) ->
     %% REM: determine date range dependent on time_t = Uint32 | Sint32 | Sint64 | Uint64
     %% Determine time_t on os:type()?
     lists:foreach(fun ({FI, Opts}) ->
-			 ok = ?PRIM_FILE_call(write_file_info, Handle, [Name, FI, Opts])
+			 ok = ?PRIM_FILE:write_file_info(Name, FI, Opts)
 		 end, [ {#file_info{ mode=8#400, atime = Time, mtime = Time, ctime = Time}, Opts} ||
 			  Opts <- [[{time, universal}],[{time, local}]],
 			  Time <- [
@@ -1050,11 +918,9 @@ file_write_file_info_opts(Config) when is_list(Config) ->
 				   {{2037,2,3},{23,59,59}},
 				   erlang:localtime()
 				  ]]),
-    ok   = ?PRIM_FILE:stop(Handle),
     ok.
 
 file_read_file_info_opts(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
     RootDir = get_good_directory(Config),
     io:format("RootDir = ~p", [RootDir]),
 
@@ -1063,41 +929,38 @@ file_read_file_info_opts(Config) when is_list(Config) ->
 
     lists:foreach(fun
 		      (Opts) ->
-			 {ok,_} = ?PRIM_FILE_call(read_file_info, Handle, [Name, Opts])
+			 {ok,_} = ?PRIM_FILE:read_file_info(Name, Opts)
 		 end, [[{time, Type}] || Type <- [local, universal, posix]]),
-    ok   = ?PRIM_FILE:stop(Handle),
     ok.
 
 %% Test the write and read back *_file_info/3 functions.
 
 file_write_read_file_info_opts(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
     RootDir = get_good_directory(Config),
     io:format("RootDir = ~p", [RootDir]),
 
     Name = filename:join(RootDir, atom_to_list(?MODULE) ++"_read_write_file_info_opts"),
     ok   = ?PRIM_FILE:write_file(Name, "hello_opts2"),
 
-    ok = file_write_read_file_info_opts(Handle, Name, {{1989, 04, 28}, {19,30,22}}, [{time, local}]),
-    ok = file_write_read_file_info_opts(Handle, Name, {{1989, 04, 28}, {19,30,22}}, [{time, universal}]),
+    ok = file_write_read_file_info_opts(Name, {{1989, 04, 28}, {19,30,22}}, [{time, local}]),
+    ok = file_write_read_file_info_opts(Name, {{1989, 04, 28}, {19,30,22}}, [{time, universal}]),
     %% will not work on platforms with unsigned time_t
-    %ok = file_write_read_file_info_opts(Handle, Name, {{1930, 04, 28}, {19,30,22}}, [{time, local}]),
-    %ok = file_write_read_file_info_opts(Handle, Name, {{1930, 04, 28}, {19,30,22}}, [{time, universal}]),
-    ok = file_write_read_file_info_opts(Handle, Name, 1, [{time, posix}]),
+    %ok = file_write_read_file_info_opts(Name, {{1930, 04, 28}, {19,30,22}}, [{time, local}]),
+    %ok = file_write_read_file_info_opts(Name, {{1930, 04, 28}, {19,30,22}}, [{time, universal}]),
+    ok = file_write_read_file_info_opts(Name, 1, [{time, posix}]),
     %% will not work on platforms with unsigned time_t
-    %ok = file_write_read_file_info_opts(Handle, Name, -1, [{time, posix}]),
-    %ok = file_write_read_file_info_opts(Handle, Name, -300000, [{time, posix}]),
-    ok = file_write_read_file_info_opts(Handle, Name, 300000, [{time, posix}]),
-    ok = file_write_read_file_info_opts(Handle, Name, 0, [{time, posix}]),
+    %ok = file_write_read_file_info_opts(Name, -1, [{time, posix}]),
+    %ok = file_write_read_file_info_opts(Name, -300000, [{time, posix}]),
+    ok = file_write_read_file_info_opts(Name, 300000, [{time, posix}]),
+    ok = file_write_read_file_info_opts(Name, 0, [{time, posix}]),
 
-    ok = ?PRIM_FILE:stop(Handle),
     ok.
 
-file_write_read_file_info_opts(Handle, Name, Mtime, Opts) ->
-    {ok, FI} = ?PRIM_FILE_call(read_file_info, Handle, [Name, Opts]),
+file_write_read_file_info_opts(Name, Mtime, Opts) ->
+    {ok, FI} = ?PRIM_FILE:read_file_info(Name, Opts),
     FI2 = FI#file_info{ mtime = Mtime },
-    ok = ?PRIM_FILE_call(write_file_info, Handle, [Name, FI2, Opts]),
-    {ok, FI3} = ?PRIM_FILE_call(read_file_info, Handle, [Name, Opts]),
+    ok = ?PRIM_FILE:write_file_info(Name, FI2, Opts),
+    {ok, FI3} = ?PRIM_FILE:read_file_info(Name, Opts),
     io:format("Expecting mtime = ~p, got ~p~n", [FI2#file_info.mtime, FI3#file_info.mtime]),
     FI2 = FI3,
     ok.
@@ -1175,8 +1038,8 @@ advise(Config) when is_list(Config) ->
 			   atom_to_list(?MODULE)
 			   ++"_advise.fil"),
 
-    Line1 = "Hello\n",
-    Line2 = "World!\n",
+    Line1 = <<"Hello\n">>,
+    Line2 = <<"World!\n">>,
 
     {ok, Fd} = ?PRIM_FILE:open(Advise, [write]),
     ok = ?PRIM_FILE:advise(Fd, 0, 0, normal),
@@ -1226,7 +1089,7 @@ advise(Config) when is_list(Config) ->
     {ok, Fd9} = ?PRIM_FILE:open(Advise, [read]),
     Offset = 0,
     %% same as a 0 length in some implementations
-    Length = length(Line1) + length(Line2),
+    Length = byte_size(Line1) + byte_size(Line2),
     ok = ?PRIM_FILE:advise(Fd9, Offset, Length, sequential),
     {ok, Line1} = ?PRIM_FILE:read_line(Fd9),
     {ok, Line2} = ?PRIM_FILE:read_line(Fd9),
@@ -1250,23 +1113,18 @@ do_large_write(Name) ->
     Chunk = <<0:ChunkSize/unit:8>>,
     Data = zip_data(lists:duplicate(Chunks, Chunk), Interleave),
     Size = Chunks * ChunkSize + Chunks,	% 4 G + 32
-    Wordsize = erlang:system_info(wordsize),
-    case prim_file:write_file(Name, Data) of
-	ok when Wordsize =:= 8 ->
-	    {ok,#file_info{size=Size}} = file:read_file_info(Name),
-	    {ok,Fd} = prim_file:open(Name, [read]),
-	    check_large_write(Fd, ChunkSize, 0, Interleave);
-	{error,einval} when Wordsize =:= 4 ->
-	    ok
-    end.
+    ok = ?PRIM_FILE:write_file(Name, Data),
+    {ok,#file_info{size=Size}} = file:read_file_info(Name),
+    {ok,Fd} = ?PRIM_FILE:open(Name, [read]),
+    check_large_write(Fd, ChunkSize, 0, Interleave).
 
 check_large_write(Fd, ChunkSize, Pos, [X|Interleave]) ->
     Pos1 = Pos + ChunkSize,
-    {ok,Pos1} = prim_file:position(Fd, {cur,ChunkSize}),
-    {ok,[X]} = prim_file:read(Fd, 1),
+    {ok,Pos1} = ?PRIM_FILE:position(Fd, {cur,ChunkSize}),
+    {ok,<<X>>} = ?PRIM_FILE:read(Fd, 1),
     check_large_write(Fd, ChunkSize, Pos1+1, Interleave);
 check_large_write(Fd, _, _, []) ->
-    eof = prim_file:read(Fd, 1),
+    eof = ?PRIM_FILE:read(Fd, 1),
     ok.
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -1338,71 +1196,53 @@ allocate_and_assert(Fd, Offset, Length) ->
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-delete_a(Config) when is_list(Config) ->
-    delete(Config, [], "_a").
-
-delete_b(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
-    Result = delete(Config, Handle, "_b"),
-    ok = ?PRIM_FILE:stop(Handle),
-    Result.
-
-delete(Config, Handle, Suffix) ->
+delete(Config) when is_list(Config) ->
     RootDir = proplists:get_value(priv_dir,Config),
     Name = filename:join(RootDir,
 			 atom_to_list(?MODULE)
-			 ++"_delete"++Suffix++".fil"),
+			 ++"_delete.fil"),
     {ok, Fd1} = ?PRIM_FILE:open(Name, [write]),
     ?PRIM_FILE:write(Fd1,"ok.\n"),
     ok = ?PRIM_FILE:close(Fd1),
     %% Check that the file is readable
     {ok, Fd2} = ?PRIM_FILE:open(Name, [read]),
     ok = ?PRIM_FILE:close(Fd2),
-    ok = ?PRIM_FILE_call(delete, Handle, [Name]),
+    ok = ?PRIM_FILE:delete(Name),
     %% Check that the file is not readable anymore
     {error, _} = ?PRIM_FILE:open(Name, [read]),
     %% Try deleting a nonexistent file
-    {error, enoent} = ?PRIM_FILE_call(delete, Handle, [Name]),
+    {error, enoent} = ?PRIM_FILE:delete(Name),
     ok.
 
-rename_a(Config) when is_list(Config) ->
-    rename(Config, [], "_a").
-
-rename_b(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
-    Result = rename(Config, Handle, "_b"),
-    ok = ?PRIM_FILE:stop(Handle),
-    Result.
-
-rename(Config, Handle, Suffix) ->
+rename(Config) when is_list(Config) ->
     RootDir = proplists:get_value(priv_dir,Config),
-    FileName1 = atom_to_list(?MODULE)++"_rename"++Suffix++".fil",
-    FileName2 = atom_to_list(?MODULE)++"_rename"++Suffix++".ful",
+    FileName1 = atom_to_list(?MODULE)++"_rename.fil",
+    FileName2 = atom_to_list(?MODULE)++"_rename.ful",
     Name1 = filename:join(RootDir, FileName1),
     Name2 = filename:join(RootDir, FileName2),
     {ok,Fd1} = ?PRIM_FILE:open(Name1, [write]),
     ok = ?PRIM_FILE:close(Fd1),
     %% Rename, and check that it really changed name
-    ok = ?PRIM_FILE_call(rename, Handle, [Name1, Name2]),
+    ok = ?PRIM_FILE:rename(Name1, Name2),
     {error, _} = ?PRIM_FILE:open(Name1, [read]),
     {ok, Fd2} = ?PRIM_FILE:open(Name2, [read]),
     ok = ?PRIM_FILE:close(Fd2),
     %% Try renaming something to itself
-    ok = ?PRIM_FILE_call(rename, Handle, [Name2, Name2]),
+    ok = ?PRIM_FILE:rename(Name2, Name2),
     %% Try renaming something that doesn't exist
     {error, enoent} =
-	?PRIM_FILE_call(rename, Handle, [Name1, Name2]),
+	?PRIM_FILE:rename(Name1, Name2),
     %% Try renaming to something else than a string
     {error, badarg} =
-	?PRIM_FILE_call(rename, Handle, [Name1, foobar]),
+	?PRIM_FILE:rename(Name1, foobar),
 
     %% Move between directories
     DirName1 = filename:join(RootDir,
 			     atom_to_list(?MODULE)
-			     ++"_rename_dir"++Suffix),
+			     ++"_rename_dir"),
     DirName2 = filename:join(RootDir,
 			     atom_to_list(?MODULE)
-			     ++"_second_rename_dir"++Suffix),
+			     ++"_second_rename_dir"),
     Name1foo = filename:join(DirName1, "foo.fil"),
     Name2foo = filename:join(DirName2, "foo.fil"),
     Name2bar = filename:join(DirName2, "bar.dir"),
@@ -1410,21 +1250,21 @@ rename(Config, Handle, Suffix) ->
     %% The name has to include the full file name, path is not enough
     expect(
       {error, eexist}, {error, eisdir},
-      ?PRIM_FILE_call(rename, Handle, [Name2, DirName1])),
+      ?PRIM_FILE:rename(Name2, DirName1)),
     ok =
-	?PRIM_FILE_call(rename, Handle, [Name2, Name1foo]),
+	?PRIM_FILE:rename(Name2, Name1foo),
     %% Now rename the directory
-    ok = ?PRIM_FILE_call(rename, Handle, [DirName1, DirName2]),
+    ok = ?PRIM_FILE:rename(DirName1, DirName2),
     %% And check that the file is there now
     {ok,Fd3} = ?PRIM_FILE:open(Name2foo, [read]),
     ok = ?PRIM_FILE:close(Fd3),
     %% Try some dirty things now: move the directory into itself
     {error, Msg1} =
-	?PRIM_FILE_call(rename, Handle, [DirName2, Name2bar]),
+	?PRIM_FILE:rename(DirName2, Name2bar),
     io:format("Errmsg1: ~p",[Msg1]),
     %% move dir into a file in itself
     {error, Msg2} =
-	?PRIM_FILE_call(rename, Handle, [DirName2, Name2foo]),
+	?PRIM_FILE:rename(DirName2, Name2foo),
     io:format("Errmsg2: ~p",[Msg2]),
 
     ok.
@@ -1657,165 +1497,19 @@ e_del_dir(Config) when is_list(Config) ->
     ok.
 
 
-%% Trying reading and positioning from a compressed file.
-
-read_compressed(Config) when is_list(Config) ->
-    Data = proplists:get_value(data_dir, Config),
-    Real = filename:join(Data, "realmen.html.gz"),
-    {ok, Fd} = ?PRIM_FILE:open(Real, [read, compressed]),
-    try_read_file(Fd).
-
-%% Trying reading and positioning from an uncompressed file,
-%% but with the compressed flag given.
-
-read_not_really_compressed(Config) when is_list(Config) ->
-    Data = proplists:get_value(data_dir, Config),
-    Priv = proplists:get_value(priv_dir, Config),
-
-    %% The file realmen.html might have got CRs added (by WinZip).
-    %% Remove them, or the file positions will not be correct.
-
-    Real = filename:join(Data, "realmen.html"),
-    RealPriv = filename:join(Priv,
-			     atom_to_list(?MODULE)++"_realmen.html"),
-    {ok, RealDataBin} = ?PRIM_FILE:read_file(Real),
-    RealData = remove_crs(binary_to_list(RealDataBin), []),
-    ok = ?PRIM_FILE:write_file(RealPriv, RealData),
-    {ok, Fd} = ?PRIM_FILE:open(RealPriv, [read, compressed]),
-    try_read_file(Fd).
-
-remove_crs([$\r|Rest], Result) ->
-    remove_crs(Rest, Result);
-remove_crs([C|Rest], Result) ->
-    remove_crs(Rest, [C|Result]);
-remove_crs([], Result) ->
-    lists:reverse(Result).
-
-try_read_file(Fd) ->
-    %% Seek to the current position (nothing should happen).
-
-    {ok, 0} = ?PRIM_FILE:position(Fd, 0),
-    {ok, 0} = ?PRIM_FILE:position(Fd, {cur, 0}),
-
-    %% Read a few lines from a compressed file.
-
-    ShouldBe = "<TITLE>Real Programmers Don't Use PASCAL</TITLE>\n",
-    {ok, ShouldBe} = ?PRIM_FILE:read(Fd, length(ShouldBe)),
-
-    %% Now seek forward.
-
-    {ok, 381} = ?PRIM_FILE:position(Fd, 381),
-    Back = "Back in the good old days -- the \"Golden Era\" " ++
-	"of computers, it was\n",
-    {ok, Back} = ?PRIM_FILE:read(Fd, length(Back)),
-
-    %% Try to search forward relative to the current position.
-
-    {ok, CurPos} = ?PRIM_FILE:position(Fd, {cur, 0}),
-    RealPos = 4273,
-    {ok, RealPos} = ?PRIM_FILE:position(Fd, {cur, RealPos-CurPos}),
-    RealProg = "<LI> Real Programmers aren't afraid to use GOTOs.\n",
-    {ok, RealProg} = ?PRIM_FILE:read(Fd, length(RealProg)),
-
-    %% Seek backward.
-
-    AfterTitle = length("<TITLE>"),
-    {ok, AfterTitle} = ?PRIM_FILE:position(Fd, AfterTitle),
-    Title = "Real Programmers Don't Use PASCAL</TITLE>\n",
-    {ok, Title} = ?PRIM_FILE:read(Fd, length(Title)),
-
-    %% Done.
-
-    ?PRIM_FILE:close(Fd),
-    ok.
-
-write_compressed(Config) when is_list(Config) ->
-    Priv = proplists:get_value(priv_dir, Config),
-    MyFile = filename:join(Priv,
-			   atom_to_list(?MODULE)++"_test.gz"),
-
-    %% Write a file.
-
-    {ok, Fd} = ?PRIM_FILE:open(MyFile, [write, compressed]),
-    {ok, 0} = ?PRIM_FILE:position(Fd, 0),
-    Prefix = "hello\n",
-    End = "end\n",
-    ok = ?PRIM_FILE:write(Fd, Prefix),
-    {ok, 143} = ?PRIM_FILE:position(Fd, 143),
-    ok = ?PRIM_FILE:write(Fd, End),
-    ok = ?PRIM_FILE:close(Fd),
-
-    %% Read the file and verify the contents.
-
-    {ok, Fd1} = ?PRIM_FILE:open(MyFile, [read, compressed]),
-    {ok, Prefix} = ?PRIM_FILE:read(Fd1, length(Prefix)),
-    Second = lists:duplicate(143-length(Prefix), 0) ++ End,
-    {ok, Second} = ?PRIM_FILE:read(Fd1, length(Second)),
-    ok = ?PRIM_FILE:close(Fd1),
-
-    %% Ensure that the file is compressed.
-
-    TotalSize = 143 + length(End),
-    case ?PRIM_FILE:read_file_info(MyFile) of
-	{ok, #file_info{size=Size}} when Size < TotalSize ->
-	    ok;
-	{ok, #file_info{size=Size}} when Size == TotalSize ->
-	    ct:fail(file_not_compressed)
-    end,
-
-    %% Write again to ensure that the file is truncated.
-
-    {ok, Fd2} = ?PRIM_FILE:open(MyFile, [write, compressed]),
-    NewString = "aaaaaaaaaaa",
-    ok = ?PRIM_FILE:write(Fd2, NewString),
-    ok = ?PRIM_FILE:close(Fd2),
-    {ok, Fd3} = ?PRIM_FILE:open(MyFile, [read, compressed]),
-    {ok, NewString} = ?PRIM_FILE:read(Fd3, 1024),
-    ok = ?PRIM_FILE:close(Fd3),
-
-    ok.
-
-compress_errors(Config) when is_list(Config) ->
-    Data = proplists:get_value(data_dir, Config),
-    {error, enoent} = ?PRIM_FILE:open("non_existing__",
-				      [compressed, read]),
-    {error, einval} = ?PRIM_FILE:open("non_existing__",
-				      [compressed, read, write]),
-
-    %% Read a corrupted .gz file.
-
-    Corrupted = filename:join(Data, "corrupted.gz"),
-    {ok, Fd} = ?PRIM_FILE:open(Corrupted, [read, compressed]),
-    {error, eio} = ?PRIM_FILE:read(Fd, 100),
-    ?PRIM_FILE:close(Fd),
-
-    ok.
-
-
-%% Test creating a hard link.
-make_link_a(Config) when is_list(Config) ->
-    make_link(Config, [], "_a").
-
-%% Test creating a hard link.
-make_link_b(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
-    Result = make_link(Config, Handle, "_b"),
-    ok = ?PRIM_FILE:stop(Handle),
-    Result.
-
-make_link(Config, Handle, Suffix) ->
+make_link(Config) when is_list(Config) ->
     RootDir = proplists:get_value(priv_dir, Config),
     NewDir = filename:join(RootDir,
 			   atom_to_list(?MODULE)
-			   ++"_make_link"++Suffix),
-    ok = ?PRIM_FILE_call(make_dir, Handle, [NewDir]),
+			   ++"_make_link"),
+    ok = ?PRIM_FILE:make_dir(NewDir),
 
     Name = filename:join(NewDir, "a_file"),
     ok = ?PRIM_FILE:write_file(Name, "some contents\n"),
 
     Alias = filename:join(NewDir, "an_alias"),
     Result =
-	case ?PRIM_FILE_call(make_link, Handle, [Name, Alias]) of
+	case ?PRIM_FILE:make_link(Name, Alias) of
 	    {error, enotsup} ->
 		{skipped, "Links not supported on this platform"};
 	    ok ->
@@ -1826,12 +1520,12 @@ make_link(Config, Handle, Suffix) ->
 		%% since they are not used on symbolic links.
 
 		{ok, Info} =
-		    ?PRIM_FILE_call(read_link_info, Handle, [Name]),
+		    ?PRIM_FILE:read_link_info(Name),
 		{ok, Info} =
-		    ?PRIM_FILE_call(read_link_info, Handle, [Alias]),
+		    ?PRIM_FILE:read_link_info(Alias),
 		#file_info{links = 2, type = regular} = Info,
 		{error, eexist} =
-		    ?PRIM_FILE_call(make_link, Handle, [Name, Alias]),
+		    ?PRIM_FILE:make_link(Name, Alias),
 		ok
 	end,
 
@@ -1843,30 +1537,19 @@ read_link_info_for_non_link(Config) when is_list(Config) ->
     {ok, #file_info{type=directory}} = ?PRIM_FILE:read_link_info("."),
     ok.
 
-%% Test operations on symbolic links (for Unix).
-symlinks_a(Config) when is_list(Config) ->
-    symlinks(Config, [], "_a").
-
-%% Test operations on symbolic links (for Unix).
-symlinks_b(Config) when is_list(Config) ->
-    {ok, Handle} = ?PRIM_FILE:start(),
-    Result = symlinks(Config, Handle, "_b"),
-    ok = ?PRIM_FILE:stop(Handle),
-    Result.
-
-symlinks(Config, Handle, Suffix) ->
+symlinks(Config) when is_list(Config)  ->
     RootDir = proplists:get_value(priv_dir, Config),
     NewDir = filename:join(RootDir,
 			   atom_to_list(?MODULE)
-			   ++"_make_symlink"++Suffix),
-    ok = ?PRIM_FILE_call(make_dir, Handle, [NewDir]),
+			   ++"_make_symlink"),
+    ok = ?PRIM_FILE:make_dir(NewDir),
 
     Name = filename:join(NewDir, "a_plain_file"),
     ok = ?PRIM_FILE:write_file(Name, "some stupid content\n"),
 
     Alias = filename:join(NewDir, "a_symlink_alias"),
     Result =
-	case ?PRIM_FILE_call(make_symlink, Handle, [Name, Alias]) of
+	case ?PRIM_FILE:make_symlink(Name, Alias) of
 	    {error, enotsup} ->
 		{skipped, "Links not supported on this platform"};
 	    {error, eperm} ->
@@ -1874,20 +1557,20 @@ symlinks(Config, Handle, Suffix) ->
 		{skipped, "Windows user not privileged to create links"};
 	    ok ->
 		{ok, Info1} =
-		    ?PRIM_FILE_call(read_file_info, Handle, [Name]),
+		    ?PRIM_FILE:read_file_info(Name),
 		{ok, Info1} =
-		    ?PRIM_FILE_call(read_file_info, Handle, [Alias]),
+		    ?PRIM_FILE:read_file_info(Alias),
 		{ok, Info1} =
-		    ?PRIM_FILE_call(read_link_info, Handle, [Name]),
+		    ?PRIM_FILE:read_link_info(Name),
 		#file_info{links = 1, type = regular} = Info1,
 
 		{ok, Info2} =
-		    ?PRIM_FILE_call(read_link_info, Handle, [Alias]),
+		    ?PRIM_FILE:read_link_info(Alias),
 		#file_info{links=1, type=symlink} = Info2,
 		{ok, Name} =
-		    ?PRIM_FILE_call(read_link, Handle, [Alias]),
+		    ?PRIM_FILE:read_link(Alias),
 		{ok, Name} =
-		    ?PRIM_FILE_call(read_link_all, Handle, [Alias]),
+		    ?PRIM_FILE:read_link_all(Alias),
 		%% If all is good, delete dir again (avoid hanging dir on windows)
 		rm_rf(?PRIM_FILE,NewDir),
 		ok
@@ -1907,10 +1590,9 @@ list_dir_limit(Config) when is_list(Config) ->
     RootDir = proplists:get_value(priv_dir, Config),
     NewDir = filename:join(RootDir,
 			   atom_to_list(?MODULE)++"_list_dir_limit"),
-    {ok, Handle1} = ?PRIM_FILE:start(),
-    ok = ?PRIM_FILE_call(make_dir, Handle1, [NewDir]),
+    ok = ?PRIM_FILE:make_dir(NewDir),
     Ref = erlang:start_timer(MaxTime*1000, self(), []),
-    Result = list_dir_limit_loop(NewDir, Handle1, Ref, MaxNumber, 0),
+    Result = list_dir_limit_loop(NewDir, Ref, MaxNumber, 0),
     Time = case erlang:cancel_timer(Ref) of
 	       false -> MaxTime;
 	       T -> MaxTime - (T div 1000)
@@ -1920,21 +1602,18 @@ list_dir_limit(Config) when is_list(Config) ->
 		 {error, _Reason, N} -> N;
 		 _ -> 0
 	     end,
-    {ok, Handle2} = ?PRIM_FILE:start(),
-    list_dir_limit_cleanup(NewDir, Handle2, Number, 0),
-    ok = ?PRIM_FILE:stop(Handle1),
-    ok = ?PRIM_FILE:stop(Handle2),
+    list_dir_limit_cleanup(NewDir, Number, 0),
     {ok, Number} = Result,
     {comment, 
      "Created " ++ integer_to_list(Number) ++ " files in " 
      ++ integer_to_list(Time) ++ " seconds."}.
 
-list_dir_limit_loop(Dir, Handle, _Ref, N, Cnt) when Cnt >= N ->
-    list_dir_check(Dir, Handle, Cnt);
-list_dir_limit_loop(Dir, Handle, Ref, N, Cnt) ->
+list_dir_limit_loop(Dir, _Ref, N, Cnt) when Cnt >= N ->
+    list_dir_check(Dir, Cnt);
+list_dir_limit_loop(Dir, Ref, N, Cnt) ->
     receive 
 	{timeout, Ref, []} -> 
-	    list_dir_check(Dir, Handle, Cnt)
+	    list_dir_check(Dir, Cnt)
     after 0 ->
 	    Name = integer_to_list(Cnt),
 	    case ?PRIM_FILE:write_file(filename:join(Dir, Name), Name) of
@@ -1942,23 +1621,23 @@ list_dir_limit_loop(Dir, Handle, Ref, N, Cnt) ->
 		    Next = Cnt + 1,
 		    case Cnt rem 100 of
 			0 ->
-			    case list_dir_check(Dir, Handle, Next) of
+			    case list_dir_check(Dir, Next) of
 				{ok, Next} ->
 				    list_dir_limit_loop(
-				      Dir, Handle, Ref, N, Next);
+				      Dir, Ref, N, Next);
 				Other ->
 				    Other
 			    end;
 			_ ->
-			    list_dir_limit_loop(Dir, Handle, Ref, N, Next)
+			    list_dir_limit_loop(Dir, Ref, N, Next)
 		    end;
 		{error, Reason} ->
 		    {error, Reason, Cnt}
 	    end
     end.
 
-list_dir_check(Dir, Handle, Cnt) ->
-    case ?PRIM_FILE:list_dir(Handle, Dir) of
+list_dir_check(Dir, Cnt) ->
+    case ?PRIM_FILE:list_dir(Dir) of
 	{ok, ListDir} ->
 	    case length(ListDir) of
 		Cnt ->
@@ -1975,18 +1654,18 @@ list_dir_check(Dir, Handle, Cnt) ->
 %% Deletes N files while ignoring errors, then continues deleting
 %% as long as they exist.
 
-list_dir_limit_cleanup(Dir, Handle, N, Cnt) when Cnt >= N ->
+list_dir_limit_cleanup(Dir, N, Cnt) when Cnt >= N ->
     Name = integer_to_list(Cnt),
-    case ?PRIM_FILE:delete(Handle, filename:join(Dir, Name)) of
+    case ?PRIM_FILE:delete(filename:join(Dir, Name)) of
 	ok ->
-	    list_dir_limit_cleanup(Dir, Handle, N, Cnt+1);
+	    list_dir_limit_cleanup(Dir, N, Cnt+1);
 	_ ->
 	    ok
     end;
-list_dir_limit_cleanup(Dir, Handle, N, Cnt) ->
+list_dir_limit_cleanup(Dir, N, Cnt) ->
     Name = integer_to_list(Cnt),
-    ?PRIM_FILE:delete(Handle, filename:join(Dir, Name)),
-    list_dir_limit_cleanup(Dir, Handle, N, Cnt+1).
+    ?PRIM_FILE:delete(filename:join(Dir, Name)),
+    list_dir_limit_cleanup(Dir, N, Cnt+1).
 
 %%%
 %%% Test list_dir() on a non-existing pathname.
@@ -1995,7 +1674,7 @@ list_dir_limit_cleanup(Dir, Handle, N, Cnt) ->
 list_dir_error(Config) ->
     Priv = proplists:get_value(priv_dir, Config),
     NonExisting = filename:join(Priv, "non-existing-dir"),
-    {error,enoent} = prim_file:list_dir(NonExisting),
+    {error,enoent} = ?PRIM_FILE:list_dir(NonExisting),
     ok.
 
 %%%
@@ -2063,7 +1742,7 @@ do_run_large_file_test(Config, Run, Name0) ->
 		      {'DOWN',Mref,_,_,_} -> ok;
 		      {Tester,done} -> ok
 		  end,
-		  prim_file:delete(Name)
+		  ?PRIM_FILE:delete(Name)
 	  end),
 
     %% Run the test case.
diff --git a/lib/kernel/test/sendfile_SUITE.erl b/lib/kernel/test/sendfile_SUITE.erl
index bfa564c32c..0c0b1cbcb6 100644
--- a/lib/kernel/test/sendfile_SUITE.erl
+++ b/lib/kernel/test/sendfile_SUITE.erl
@@ -23,30 +23,41 @@
 -include_lib("common_test/include/ct.hrl").
 -include_lib("kernel/include/file.hrl").
 
--compile(export_all).
-
-all() -> [{group,async_threads},
-	  {group,no_async_threads}].
-
-groups() ->
-    [{async_threads,[],tcs()},
-     {no_async_threads,[],tcs()}].
-
-tcs() ->
-    [t_sendfile_small
-     ,t_sendfile_big_all
-     ,t_sendfile_big_size
-     ,t_sendfile_many_small
-     ,t_sendfile_partial
-     ,t_sendfile_offset
-     ,t_sendfile_sendafter
-     ,t_sendfile_recvafter
-     ,t_sendfile_recvafter_remoteclose
-     ,t_sendfile_sendduring
-     ,t_sendfile_recvduring
-     ,t_sendfile_closeduring
-     ,t_sendfile_crashduring
-    ].
+-export([all/0, init_per_suite/1, end_per_suite/1, init_per_testcase/2]).
+
+-export([sendfile_server/2, sendfile_do_recv/2, init/1, handle_event/2]).
+
+-export(
+    [t_sendfile_small/1,
+     t_sendfile_big_all/1,
+     t_sendfile_big_size/1,
+     t_sendfile_many_small/1,
+     t_sendfile_partial/1,
+     t_sendfile_offset/1,
+     t_sendfile_sendafter/1,
+     t_sendfile_recvafter/1,
+     t_sendfile_recvafter_remoteclose/1,
+     t_sendfile_sendduring/1,
+     t_sendfile_recvduring/1,
+     t_sendfile_closeduring/1,
+     t_sendfile_crashduring/1,
+     t_sendfile_arguments/1]).
+
+all() ->
+    [t_sendfile_small,
+     t_sendfile_big_all,
+     t_sendfile_big_size,
+     t_sendfile_many_small,
+     t_sendfile_partial,
+     t_sendfile_offset,
+     t_sendfile_sendafter,
+     t_sendfile_recvafter,
+     t_sendfile_recvafter_remoteclose,
+     t_sendfile_sendduring,
+     t_sendfile_recvduring,
+     t_sendfile_closeduring,
+     t_sendfile_crashduring,
+     t_sendfile_arguments].
 
 init_per_suite(Config) ->
     case {os:type(),os:version()} of
@@ -72,28 +83,18 @@ init_per_suite(Config) ->
 end_per_suite(Config) ->
     file:delete(proplists:get_value(big_file, Config)).
 
-init_per_group(async_threads,Config) ->
-    case erlang:system_info(thread_pool_size) of
-	0 ->
-	    {skip,"No async threads"};
-	_ ->
-	    [{sendfile_opts,[{use_threads,true}]}|Config]
-    end;
-init_per_group(no_async_threads,Config) ->
-    [{sendfile_opts,[{use_threads,false}]}|Config].
-
-end_per_group(_,_Config) ->
-    ok.
-
 init_per_testcase(TC,Config) when TC == t_sendfile_recvduring;
 				  TC == t_sendfile_sendduring ->
     Filename = proplists:get_value(small_file, Config),
 
     Send = fun(Sock) ->
 		   {_Size, Data} = sendfile_file_info(Filename),
-		   {ok,D} = file:open(Filename, [raw,binary,read]),
-		   prim_file:sendfile(D, Sock, 0, 0, 0,
-				      [],[],[]),
+		   {ok,Fd} = file:open(Filename, [raw,binary,read]),
+                   %% Determine whether the driver has native support by
+                   %% hitting the raw module directly; file:sendfile/5 will
+                   %% land in the fallback if it doesn't.
+                   RawModule = Fd#file_descriptor.module,
+                   {ok, _Ignored} = RawModule:sendfile(Fd,Sock,0,0,0,[],[],[]),
 		   Data
 	   end,
 
@@ -105,9 +106,8 @@ init_per_testcase(TC,Config) when TC == t_sendfile_recvduring;
 	    ct:log("Error: ~p",[Error]),
 	    {skip,"Not supported"}
     end;
-init_per_testcase(_Tc,Config) ->
-    Config ++ [{sendfile_opts,[{use_threads,false}]}].
-
+init_per_testcase(_TC,Config) ->
+    Config.
 
 t_sendfile_small(Config) when is_list(Config) ->
     Filename = proplists:get_value(small_file, Config),
@@ -124,7 +124,7 @@ t_sendfile_small(Config) when is_list(Config) ->
 t_sendfile_many_small(Config) when is_list(Config) ->
     Filename = proplists:get_value(small_file, Config),
     FileOpts = proplists:get_value(file_opts, Config, []),
-    SendfileOpts = proplists:get_value(sendfile_opts, Config),
+    SendfileOpts = proplists:get_value(sendfile_opts, Config, []),
 
     error_logger:add_report_handler(?MODULE,[self()]),
 
@@ -151,7 +151,7 @@ t_sendfile_many_small(Config) when is_list(Config) ->
 
 t_sendfile_big_all(Config) when is_list(Config) ->
     Filename = proplists:get_value(big_file, Config),
-    SendfileOpts = proplists:get_value(sendfile_opts, Config),
+    SendfileOpts = proplists:get_value(sendfile_opts, Config, []),
 
     Send = fun(Sock) ->
 		   {ok, #file_info{size = Size}} =
@@ -165,7 +165,7 @@ t_sendfile_big_all(Config) when is_list(Config) ->
 t_sendfile_big_size(Config) ->
     Filename = proplists:get_value(big_file, Config),
     FileOpts = proplists:get_value(file_opts, Config, []),
-    SendfileOpts = proplists:get_value(sendfile_opts, Config),
+    SendfileOpts = proplists:get_value(sendfile_opts, Config, []),
 
     SendAll = fun(Sock) ->
 		      {ok, #file_info{size = Size}} =
@@ -180,7 +180,7 @@ t_sendfile_big_size(Config) ->
 t_sendfile_partial(Config) ->
     Filename = proplists:get_value(small_file, Config),
     FileOpts = proplists:get_value(file_opts, Config, []),
-    SendfileOpts = proplists:get_value(sendfile_opts, Config),
+    SendfileOpts = proplists:get_value(sendfile_opts, Config, []),
 
     SendSingle = fun(Sock) ->
 			 {_Size, <<Data:5/binary,_/binary>>} =
@@ -217,7 +217,7 @@ t_sendfile_partial(Config) ->
 t_sendfile_offset(Config) ->
     Filename = proplists:get_value(small_file, Config),
     FileOpts = proplists:get_value(file_opts, Config, []),
-    SendfileOpts = proplists:get_value(sendfile_opts, Config),
+    SendfileOpts = proplists:get_value(sendfile_opts, Config, []),
 
     Send = fun(Sock) ->
 		   {_Size, <<_:5/binary,Data:3/binary,_/binary>> = AllData} =
@@ -233,7 +233,7 @@ t_sendfile_offset(Config) ->
 
 t_sendfile_sendafter(Config) ->
     Filename = proplists:get_value(small_file, Config),
-    SendfileOpts = proplists:get_value(sendfile_opts, Config),
+    SendfileOpts = proplists:get_value(sendfile_opts, Config, []),
 
     Send = fun(Sock) ->
 		   {Size, Data} = sendfile_file_info(Filename),
@@ -246,7 +246,7 @@ t_sendfile_sendafter(Config) ->
 
 t_sendfile_recvafter(Config) ->
     Filename = proplists:get_value(small_file, Config),
-    SendfileOpts = proplists:get_value(sendfile_opts, Config),
+    SendfileOpts = proplists:get_value(sendfile_opts, Config, []),
 
     Send = fun(Sock) ->
 		   {Size, Data} = sendfile_file_info(Filename),
@@ -279,7 +279,7 @@ t_sendfile_recvafter_remoteclose(Config) ->
 
 t_sendfile_sendduring(Config) ->
     Filename = proplists:get_value(big_file, Config),
-    SendfileOpts = proplists:get_value(sendfile_opts, Config),
+    SendfileOpts = proplists:get_value(sendfile_opts, Config, []),
 
     Send = fun(Sock) ->
 		   {ok, #file_info{size = Size}} =
@@ -296,7 +296,7 @@ t_sendfile_sendduring(Config) ->
 
 t_sendfile_recvduring(Config) ->
     Filename = proplists:get_value(big_file, Config),
-    SendfileOpts = proplists:get_value(sendfile_opts, Config),
+    SendfileOpts = proplists:get_value(sendfile_opts, Config, []),
 
     Send = fun(Sock) ->
 		   {ok, #file_info{size = Size}} =
@@ -315,7 +315,7 @@ t_sendfile_recvduring(Config) ->
 
 t_sendfile_closeduring(Config) ->
     Filename = proplists:get_value(big_file, Config),
-    SendfileOpts = proplists:get_value(sendfile_opts, Config),
+    SendfileOpts = proplists:get_value(sendfile_opts, Config, []),
 
     Send = fun(Sock,SFServPid) ->
 		   spawn_link(fun() ->
@@ -345,7 +345,7 @@ t_sendfile_closeduring(Config) ->
 
 t_sendfile_crashduring(Config) ->
     Filename = proplists:get_value(big_file, Config),
-    SendfileOpts = proplists:get_value(sendfile_opts, Config),
+    SendfileOpts = proplists:get_value(sendfile_opts, Config, []),
 
     error_logger:add_report_handler(?MODULE,[self()]),
 
@@ -373,6 +373,36 @@ t_sendfile_crashduring(Config) ->
 		end
 	end.
 
+t_sendfile_arguments(Config) ->
+    Filename = proplists:get_value(small_file, Config),
+
+    {ok, Listener} = gen_tcp:listen(0,
+        [{packet, 0}, {active, false}, {reuseaddr, true}]),
+    {ok, Port} = inet:port(Listener),
+
+    ErrorCheck =
+        fun(Reason, Offset, Length, Opts) ->
+            {ok, Sender} = gen_tcp:connect({127, 0, 0, 1}, Port,
+                [{packet, 0}, {active, false}]),
+            {ok, Receiver} = gen_tcp:accept(Listener),
+            {ok, Fd} = file:open(Filename, [read, raw]),
+            {error, Reason} = file:sendfile(Fd, Sender, Offset, Length, Opts),
+            gen_tcp:close(Receiver),
+            gen_tcp:close(Sender),
+            file:close(Fd)
+        end,
+
+    ErrorCheck(einval, -1, 0, []),
+    ErrorCheck(einval, 0, -1, []),
+    ErrorCheck(badarg, gurka, 0, []),
+    ErrorCheck(badarg, 0, gurka, []),
+    ErrorCheck(badarg, 0, 0, gurka),
+    ErrorCheck(badarg, 0, 0, [{chunk_size, gurka}]),
+
+    gen_tcp:close(Listener),
+
+    ok.
+
 %% Generic sendfile server code
 sendfile_send(Send) ->
     sendfile_send({127,0,0,1},Send).
diff --git a/lib/kernel/test/zlib_SUITE.erl b/lib/kernel/test/zlib_SUITE.erl
index 26602bdcda..f203ef878f 100644
--- a/lib/kernel/test/zlib_SUITE.erl
+++ b/lib/kernel/test/zlib_SUITE.erl
@@ -1061,32 +1061,27 @@ sub_heap_binaries(Config) when is_list(Config) ->
 
 %% Check concurrent access to zlib driver.
 smp(Config) ->
-    case erlang:system_info(smp_support) of
-        true ->
-            NumOfProcs = lists:min([8,erlang:system_info(schedulers)]),
-            io:format("smp starting ~p workers\n",[NumOfProcs]),
-
-            %% Tests to run in parallel.
-            Funcs =
-                [zip_usage, gz_usage, compress_usage, dictionary_usage,
-                 crc, adler],
-
-            %% We get all function arguments here to avoid repeated parallel
-            %% file read access.
-            UsageArgs =
-                list_to_tuple([{F, ?MODULE:F({get_arg,Config})} || F <- Funcs]),
-            Parent = self(),
-
-            WorkerFun =
-                fun() ->
-                    worker(rand:uniform(9999), UsageArgs, Parent)
-                end,
-
-            Pids = [spawn_link(WorkerFun) || _ <- lists:seq(1, NumOfProcs)],
-            wait_pids(Pids);
-        false ->
-            {skipped,"No smp support"}
-    end.
+    NumOfProcs = lists:min([8,erlang:system_info(schedulers)]),
+    io:format("smp starting ~p workers\n",[NumOfProcs]),
+
+    %% Tests to run in parallel.
+    Funcs =
+        [zip_usage, gz_usage, compress_usage, dictionary_usage,
+            crc, adler],
+
+    %% We get all function arguments here to avoid repeated parallel
+    %% file read access.
+    UsageArgs =
+        list_to_tuple([{F, ?MODULE:F({get_arg,Config})} || F <- Funcs]),
+    Parent = self(),
+
+    WorkerFun =
+        fun() ->
+            worker(rand:uniform(9999), UsageArgs, Parent)
+        end,
+
+    Pids = [spawn_link(WorkerFun) || _ <- lists:seq(1, NumOfProcs)],
+    wait_pids(Pids).
 
 worker(Seed, FnATpl, Parent) ->
     io:format("smp worker ~p, seed=~p~n",[self(),Seed]),
diff --git a/lib/mnesia/doc/src/Mnesia_chap5.xmlsrc b/lib/mnesia/doc/src/Mnesia_chap5.xmlsrc
index 62759c624b..0265e0efa0 100644
--- a/lib/mnesia/doc/src/Mnesia_chap5.xmlsrc
+++ b/lib/mnesia/doc/src/Mnesia_chap5.xmlsrc
@@ -226,8 +226,10 @@
         not known beforehand, all fragments are searched for
         matching records.</p>
       <p>Notice that in <c>ordered_set</c> tables, the records
-        are ordered per fragment, and the the order is undefined in
-        results returned by <c>select</c> and <c>match_object</c>.</p>
+        are ordered per fragment, and the order is undefined in
+        results returned by <c>select</c> and <c>match_object</c>,
+        as well as <c>first</c>, <c>next</c>, <c>prev</c> and
+        <c>last</c>.</p>
       <p>The following code illustrates how a <c>Mnesia</c> table is
         converted to be a fragmented table and how more fragments
         are added later:</p>
diff --git a/lib/mnesia/src/mnesia.erl b/lib/mnesia/src/mnesia.erl
index 1842769778..95f7d4afc1 100644
--- a/lib/mnesia/src/mnesia.erl
+++ b/lib/mnesia/src/mnesia.erl
@@ -2682,7 +2682,7 @@ del_table_index(Tab, Ix) ->
 
 -spec transform_table(Tab::table(), Fun, [Attr]) -> t_result(ok) when
       Attr :: atom(),
-      Fun:: fun((Record::tuple()) -> Transformed::tuple()).
+      Fun:: fun((Record::tuple()) -> Transformed::tuple()) | ignore.
 transform_table(Tab, Fun, NewA) ->
     try val({Tab, record_name}) of
 	OldRN -> mnesia_schema:transform_table(Tab, Fun, NewA, OldRN)
@@ -2693,7 +2693,7 @@ transform_table(Tab, Fun, NewA) ->
 -spec transform_table(Tab::table(), Fun, [Attr], RecName) -> t_result(ok) when
       RecName :: atom(),
       Attr :: atom(),
-      Fun:: fun((Record::tuple()) -> Transformed::tuple()).
+      Fun:: fun((Record::tuple()) -> Transformed::tuple()) | ignore.
 transform_table(Tab, Fun, NewA, NewRN) ->
     mnesia_schema:transform_table(Tab, Fun, NewA, NewRN).
 
diff --git a/lib/mnesia/test/mnesia_test_lib.erl b/lib/mnesia/test/mnesia_test_lib.erl
index 0fabdc7929..78dbe7ffde 100644
--- a/lib/mnesia/test/mnesia_test_lib.erl
+++ b/lib/mnesia/test/mnesia_test_lib.erl
@@ -774,7 +774,7 @@ init_nodes([], _File, _Line) ->
 
 %% Returns [Name, Host]
 node_to_name_and_host(Node) ->
-    string:tokens(atom_to_list(Node), [$@]).
+    string:lexemes(atom_to_list(Node), [$@]).
 
 lookup_config(Key,Config) ->
     case lists:keysearch(Key,1,Config) of
diff --git a/lib/observer/src/cdv_dist_cb.erl b/lib/observer/src/cdv_dist_cb.erl
index 2b4c9f56d1..aeb34e5baf 100644
--- a/lib/observer/src/cdv_dist_cb.erl
+++ b/lib/observer/src/cdv_dist_cb.erl
@@ -78,7 +78,7 @@ init_gen_page(Parent, Info) ->
     cdv_info_wx:start_link(Parent,{Fields,Info,[]}).
 
 format({creations,Creations}) ->
-    string:join([integer_to_list(C) || C <- Creations],",");
+    lists:flatten(lists:join(",",[integer_to_list(C) || C <- Creations]));
 format(D) ->
     D.
 
diff --git a/lib/observer/src/cdv_mem_cb.erl b/lib/observer/src/cdv_mem_cb.erl
index abeddc7335..925487786c 100644
--- a/lib/observer/src/cdv_mem_cb.erl
+++ b/lib/observer/src/cdv_mem_cb.erl
@@ -49,9 +49,7 @@ gen_mem_info_fields([]) ->
     [].
 
 upper(Key) ->
-    string:join([string:to_upper([H]) ++ T || 
-		    [H|T] <- string:tokens(Key,"_")]," ").
-
+    lists:join(" ", [string:titlecase(Word) || Word <- string:split(Key, "_", all)]).
 
 %%%-----------------------------------------------------------------
 %%% Allocated areas page
diff --git a/lib/observer/src/cdv_wx.erl b/lib/observer/src/cdv_wx.erl
index c3f36cd689..0e33c9e618 100644
--- a/lib/observer/src/cdv_wx.erl
+++ b/lib/observer/src/cdv_wx.erl
@@ -130,8 +130,9 @@ init(File0) ->
 	{ok,File} ->
 	    %% Set window title
 	    T1 = "Crashdump Viewer: ",
+            FileLength = string:length(File),
 	    Title =
-		if length(File) > 70 ->
+		if FileLength > 70 ->
 			T1 ++ filename:basename(File);
 		   true ->
 			T1 ++ File
@@ -428,8 +429,9 @@ do_load_dump(Frame,FileName) ->
 	ok    ->
 	    %% Set window title
 	    T1 = "Crashdump Viewer: ",
+            FileLength = string:length(FileName),
 	    Title =
-		if length(FileName) > 70 ->
+		if FileLength > 70 ->
 			T1 ++ filename:basename(FileName);
 		   true ->
 			T1 ++ FileName
diff --git a/lib/observer/src/crashdump_viewer.erl b/lib/observer/src/crashdump_viewer.erl
index feaec5c678..f197e72b90 100644
--- a/lib/observer/src/crashdump_viewer.erl
+++ b/lib/observer/src/crashdump_viewer.erl
@@ -873,7 +873,7 @@ do_read_file(File) ->
     end.
 
 check_dump_version(Vsn) ->
-    DumpVsn = [list_to_integer(L) || L<-string:tokens(Vsn,".")],
+    DumpVsn = [list_to_integer(L) || L<-string:lexemes(Vsn,".")],
     if DumpVsn > ?max_dump_version ->
             Info =
                 "This Crashdump Viewer is too old for the given "
@@ -1357,12 +1357,12 @@ parse_monitor("{"++Str) ->
     %% Named process
     {Name,Node,Rest1} = parse_name_node(Str,[]),
     Pid = get_pid_from_name(Name,Node),
-    case parse_link(string:strip(Rest1,left,$,),[]) of
+    case parse_link(string:trim(Rest1,leading,","),[]) of
 	{Ref,"}"++Rest2} ->
 	    %% Bug in break.c - prints an extra "}" for remote
 	    %% nodes... thus the strip
 	    {{Pid,"{"++Name++","++Node++"} ("++Ref++")"},
-	     string:strip(Rest2,left,$})};
+	     string:trim(Rest2,leading,"}")};
 	{Ref,[]} ->
 	    {{Pid,"{"++Name++","++Node++"} ("++Ref++")"},[]}
     end;
@@ -1649,7 +1649,7 @@ get_ports(File) ->
 %% Converting port string to tuple to secure correct sorting. This is
 %% converted back in cdv_port_cb:format/1.
 port_to_tuple("#Port<"++Port) ->
-    [I1,I2] = string:tokens(Port,".>"),
+    [I1,I2] = string:lexemes(Port,".>"),
     {list_to_integer(I1),list_to_integer(I2)}.
 
 get_portinfo(Fd,Port) ->
@@ -1672,9 +1672,9 @@ get_portinfo(Fd,Port) ->
 	"Registered as" ->
 	    get_portinfo(Fd,Port#port{name=string(Fd)});
 	"Monitors" ->
-	    Monitors0 = string:tokens(bytes(Fd),"()"),
+	    Monitors0 = string:lexemes(bytes(Fd),"()"),
 	    Monitors = [begin
-			    [Pid,Ref] = string:tokens(Mon,","),
+			    [Pid,Ref] = string:lexemes(Mon,","),
 			    {Pid,Pid++" ("++Ref++")"}
 			end || Mon <- Monitors0],
 	    get_portinfo(Fd,Port#port{monitors=Monitors});
@@ -1735,7 +1735,7 @@ get_etsinfo(Fd,EtsTable = #ets_table{details=Ds},WS) ->
 	"Buckets" ->
 	    %% A bug in erl_db_hash.c prints a space after the buckets
 	    %% - need to strip the string to make list_to_integer/1 happy.
-	    Buckets = list_to_integer(string:strip(bytes(Fd))),
+	    Buckets = list_to_integer(string:trim(bytes(Fd),both,"\s")),
 	    get_etsinfo(Fd,EtsTable#ets_table{buckets=Buckets},WS);
 	"Objects" ->
 	    get_etsinfo(Fd,EtsTable#ets_table{size=list_to_integer(bytes(Fd))},WS);
@@ -1753,7 +1753,9 @@ get_etsinfo(Fd,EtsTable = #ets_table{details=Ds},WS) ->
 	    Val = bytes(Fd),
 	    get_etsinfo(Fd,EtsTable#ets_table{details=Ds#{chain_min=>Val}},WS);
 	"Chain Length Avg" ->
-	    Val = try list_to_float(string:strip(bytes(Fd))) catch _:_ -> "-" end,
+	    Val = try list_to_float(string:trim(bytes(Fd),both,"\s"))
+                  catch _:_ -> "-"
+                  end,
 	    get_etsinfo(Fd,EtsTable#ets_table{details=Ds#{chain_avg=>Val}},WS);
 	"Chain Length Max" ->
 	    Val = bytes(Fd),
@@ -1910,7 +1912,7 @@ get_nodeinfo(Fd,Nod) ->
 	    Creations = lists:flatmap(fun(C) -> try [list_to_integer(C)]
 						catch error:badarg -> []
 						end
-				      end, string:tokens(bytes(Fd)," ")),
+				      end, string:lexemes(bytes(Fd)," ")),
 	    get_nodeinfo(Fd,Nod#nod{creation={creations,Creations}});
 	"Remote link" ->
 	    Procs = bytes(Fd), % e.g. "<0.31.0> <4322.54.0>"
@@ -2344,7 +2346,7 @@ get_size_value(Key,Data) ->
 %% and Value is the sum over all allocator instances of each type.
 sort_allocator_types([{Name,Data}|Allocators],Acc,DoTotal) ->
     Type =
-	case string:tokens(Name,"[]") of
+	case string:lexemes(Name,"[]") of
 	    [T,_Id] -> T;
 	    [Name] -> Name;
             Other -> Other
diff --git a/lib/observer/src/observer_html_lib.erl b/lib/observer/src/observer_html_lib.erl
index 22b4714d63..8202f91030 100644
--- a/lib/observer/src/observer_html_lib.erl
+++ b/lib/observer/src/observer_html_lib.erl
@@ -278,24 +278,24 @@ href_proc_port("['#CDVPort'"++T,Acc,LTB) ->
     %% Port written by crashdump_viewer:parse_term(...)
     {Port0,Rest} = split($],T),
     PortStr=
-	case string:tokens(Port0,",.|") of
+	case string:lexemes(Port0,",.|") of
 	    [X,Y] ->
 		Port = "#Port&lt;"++X++"."++Y++"&gt;",
 		href(Port,Port);
 	Ns ->
-		"#Port&lt;" ++ string:join(Ns,".") ++"...&gt;"
+		"#Port&lt;" ++ lists:join($.,Ns) ++"...&gt;"
     end,
     href_proc_port(Rest,[PortStr|Acc],LTB);
 href_proc_port("['#CDVPid'"++T,Acc,LTB) ->
     %% Pid written by crashdump_viewer:parse_term(...)
     {Pid0,Rest} = split($],T),
     PidStr =
-	case string:tokens(Pid0,",.|") of
+	case string:lexemes(Pid0,",.|") of
 	    [X,Y,Z] ->
 		Pid = "&lt;"++X++"."++Y++"."++Z++"&gt;",
 		href(Pid,Pid);
 	    Ns ->
-		"&lt;" ++ string:join(Ns,".") ++ "...&gt;"
+		"&lt;" ++ lists:join($.,Ns) ++ "...&gt;"
 	end,
     href_proc_port(Rest,[PidStr|Acc],LTB);
 href_proc_port("'#CDVIncompleteHeap'"++T,Acc,LTB)->
@@ -332,7 +332,7 @@ href_proc_port([],Acc,_) ->
 href_proc_bin(From, T, Acc, LTB) ->
     {OffsetSizePos,Rest} = split($],T),
     BinStr =
-	case string:tokens(OffsetSizePos,",.| \n") of
+	case string:lexemes(OffsetSizePos,",.| \n") of
 	    [Offset,SizeStr,Pos] when From =:= cdv ->
                 Size = list_to_integer(SizeStr),
                 PreviewSize = min(Size,10),
diff --git a/lib/observer/src/observer_lib.erl b/lib/observer/src/observer_lib.erl
index 94d199e688..52e6c3e52a 100644
--- a/lib/observer/src/observer_lib.erl
+++ b/lib/observer/src/observer_lib.erl
@@ -478,7 +478,7 @@ create_box(Parent, Data) ->
 				 link_entry(Panel,Value);
 			     _ ->
 				 Value = to_str(Value0),
-                                 case string:sub_word(lists:sublist(Value, 80),1,$\n) of
+                                 case string:nth_lexeme(lists:sublist(Value, 80),1, [$\n]) of
                                      Value ->
                                          %% Short string, no newlines - show all
 					 wxStaticText:new(Panel, ?wxID_ANY, Value);
diff --git a/lib/observer/src/observer_procinfo.erl b/lib/observer/src/observer_procinfo.erl
index fb02ae2728..4ce38e439d 100644
--- a/lib/observer/src/observer_procinfo.erl
+++ b/lib/observer/src/observer_procinfo.erl
@@ -454,7 +454,8 @@ local_pid_str(Pid) ->
 
 global_pid_node_pref(Pid) ->
     %% Global PID node prefix : X of <X.Y.Z>
-    string:strip(string:sub_word(pid_to_list(Pid),1,$.),left,$<).
+    [NodePrefix|_] = string:lexemes(pid_to_list(Pid),"<."),
+    NodePrefix.
 
 io_get_data(Pid) ->
     Pid ! {self(), get_data_and_close},
diff --git a/lib/observer/src/observer_traceoptions_wx.erl b/lib/observer/src/observer_traceoptions_wx.erl
index 4f46426cf6..fbcf6d7fe9 100644
--- a/lib/observer/src/observer_traceoptions_wx.erl
+++ b/lib/observer/src/observer_traceoptions_wx.erl
@@ -619,7 +619,7 @@ create_styled_txtctrl(Parent) ->
 
 keyWords() ->
     L = ["after","begin","case","try","cond","catch","andalso","orelse",
-	 "end","fun","if","let","of","query","receive","when","bnot","not",
+	 "end","fun","if","let","of","receive","when","bnot","not",
 	 "div","rem","band","and","bor","bxor","bsl","bsr","or","xor"],
     lists:flatten([K ++ " " || K <- L] ++ [0]).
 
diff --git a/lib/observer/src/observer_wx.erl b/lib/observer/src/observer_wx.erl
index be93b1d5f1..453e3bdc2d 100644
--- a/lib/observer/src/observer_wx.erl
+++ b/lib/observer/src/observer_wx.erl
@@ -732,7 +732,7 @@ get_nodes() ->
     {Nodes, lists:reverse(Menues)}.
 
 epmd_nodes(Names) ->
-    [_, Host] = string:tokens(atom_to_list(node()),"@"),
+    [_, Host] = string:lexemes(atom_to_list(node()),"@"),
     [list_to_atom(Name ++ [$@|Host]) || {Name, _} <- Names].
 
 update_node_list(State = #state{menubar=MenuBar}) ->
diff --git a/lib/observer/src/ttb.erl b/lib/observer/src/ttb.erl
index 940fdc9818..29a572d7fe 100644
--- a/lib/observer/src/ttb.erl
+++ b/lib/observer/src/ttb.erl
@@ -100,7 +100,7 @@ do_tracer(Clients,PI,Traci) ->
 				 {ok, H} = inet:gethostname(),
 				 H;
 			     _ ->
-				 [_,H] = string:tokens(atom_to_list(N),"@"),
+				 [_,H] = string:lexemes(atom_to_list(N),"@"),
 				 H
 			 end,
 		  case catch dbg:tracer(N,port,dbg:trace_port(ip,IpPortSpec)) of
@@ -976,7 +976,7 @@ decode_filename(3,Bin,latin1) ->
     File.
 
 host(Node) ->
-    [_name,Host] = string:tokens(atom_to_list(Node),"@"),
+    [_name,Host] = string:lexemes(atom_to_list(Node),"@"),
     Host.
 
 wait_for_fetch([]) ->
@@ -1064,7 +1064,7 @@ collect_files(Dirs) ->
     lists:map(fun(Dir) ->
                       MetaFiles = filelib:wildcard(filename:join(Dir,"*.ti")),
                       lists:map(fun(M) ->
-                                        Sub = string:left(M,length(M)-3),
+                                        Sub = filename:rootname(M,".ti"),
                                         case filelib:is_file(Sub) of
                                             true -> Sub;
                                             false -> Sub++".*.wrp"
diff --git a/lib/observer/test/ttb_SUITE.erl b/lib/observer/test/ttb_SUITE.erl
index e8c2f9e37d..ed62efbb58 100644
--- a/lib/observer/test/ttb_SUITE.erl
+++ b/lib/observer/test/ttb_SUITE.erl
@@ -222,7 +222,7 @@ file_fetch(Config) when is_list(Config) ->
     ?line ?t:capture_stop(),
     ?line [StoreString] = ?t:capture_get(),
     ?line UploadDir =
-	lists:last(string:tokens(lists:flatten(StoreString),"$ \n")),
+	lists:last(string:lexemes(lists:flatten(StoreString),"$ \n")),
 
     %% check that files are no longer in original directories...
     ?line ok = check_gone(ThisDir,atom_to_list(Node)++"-file_fetch"),
@@ -1035,8 +1035,8 @@ logfile_name_in_fetch_dir(Config) when is_list(Config) ->
     ?line {ServerNode, ClientNode} = start_client_and_server(),
     ?line begin_trace(ServerNode, ClientNode, {local, ?FNAME}),
     ?line {_,Dir} = ttb:stop([return_fetch_dir]),
-    ?line P1 = lists:nth(3, string:tokens(filename:basename(Dir), "_")),
-    ?line P2 = hd(string:tokens(P1, "-")),
+    ?line P1 = lists:nth(3, string:lexemes(filename:basename(Dir), "_")),
+    ?line P2 = hd(string:lexemes(P1, "-")),
     ?line _File = P2.
 logfile_name_in_fetch_dir(cleanup,_Config) ->
     ?line stop_client_and_server().
diff --git a/lib/os_mon/src/cpu_sup.erl b/lib/os_mon/src/cpu_sup.erl
index e758b63d19..c1c972b5b1 100644
--- a/lib/os_mon/src/cpu_sup.erl
+++ b/lib/os_mon/src/cpu_sup.erl
@@ -244,7 +244,7 @@ get_uint32_measurement(Request, #internal{os_type = {unix, Sys}}) when Sys == ir
     %% Get the load average using uptime.
     %% "8:01pm  up 2 days, 22:12,  4 users,  load average: 0.70, 0.58, 0.43"
     D = os:cmd("uptime") -- "\n",
-    Avg = lists:reverse(hd(string:tokens(lists:reverse(D), ":"))),
+    Avg = lists:reverse(hd(string:lexemes(lists:reverse(D), ":"))),
     {ok, [L1, L5, L15], _} = io_lib:fread("~f, ~f, ~f", Avg),
     case Request of
 	?avg1  -> sunify(L1);
diff --git a/lib/os_mon/src/disksup.erl b/lib/os_mon/src/disksup.erl
index 044604b000..aeec335ba7 100644
--- a/lib/os_mon/src/disksup.erl
+++ b/lib/os_mon/src/disksup.erl
@@ -32,7 +32,7 @@
 	 terminate/2, code_change/3]).
 
 %% Other exports
--export([format_status/2]).
+-export([format_status/2, parse_df/2]).
 
 -record(state, {threshold, timeout, os, diskdata = [],port}).
 
@@ -294,8 +294,8 @@ check_disks_solaris("", _Threshold) ->
 check_disks_solaris("\n", _Threshold) ->
     [];
 check_disks_solaris(Str, Threshold) ->
-    case io_lib:fread("~s~d~d~d~d%~s", Str) of
-	{ok, [_FS, KB, _Used, _Avail, Cap, MntOn], RestStr} ->
+    case parse_df(Str, posix) of
+	{ok, {KB, Cap, MntOn}, RestStr} ->
 	    if
 		Cap >= Threshold ->
 		    set_alarm({disk_almost_full, MntOn}, []);
@@ -308,14 +308,102 @@ check_disks_solaris(Str, Threshold) ->
 	    check_disks_solaris(skip_to_eol(Str),Threshold)
     end.
 
+%% @private
+%% @doc Predicate to take a word from the input string until a space or
+%% a percent '%' sign (the Capacity field is followed by a %)
+parse_df_is_not_space($ ) -> false;
+parse_df_is_not_space($%) -> false;
+parse_df_is_not_space(_) -> true.
+
+%% @private
+%% @doc Predicate to take spaces away from string. Stops on a non-space
+parse_df_is_space($ ) -> true;
+parse_df_is_space(_) -> false.
+
+%% @private
+%% @doc Predicate to consume remaining characters until end of line.
+parse_df_is_not_eol($\r) -> false;
+parse_df_is_not_eol($\n) -> false;
+parse_df_is_not_eol(_)   -> true.
+
+%% @private
+%% @doc Trims leading non-spaces (the word) from the string then trims spaces.
+parse_df_skip_word(Input) ->
+    Remaining = lists:dropwhile(fun parse_df_is_not_space/1, Input),
+    lists:dropwhile(fun parse_df_is_space/1, Remaining).
+
+%% @private
+%% @doc Takes all non-spaces and then drops following spaces.
+parse_df_take_word(Input) ->
+    {Word, Remaining0} = lists:splitwith(fun parse_df_is_not_space/1, Input),
+    Remaining1 = lists:dropwhile(fun parse_df_is_space/1, Remaining0),
+    {Word, Remaining1}.
+
+%% @private
+%% @doc Takes all non-spaces and then drops the % after it and the spaces.
+parse_df_take_word_percent(Input) ->
+    {Word, Remaining0} = lists:splitwith(fun parse_df_is_not_space/1, Input),
+    %% Drop the leading % or do nothing
+    Remaining1 = case Remaining0 of
+                     [$% | R1] -> R1;
+                     _ -> Remaining0 % Might be no % or empty list even
+                 end,
+    Remaining2 = lists:dropwhile(fun parse_df_is_space/1, Remaining1),
+    {Word, Remaining2}.
+
+%% @private
+%% @doc Given a line of 'df' POSIX/SUSv3 output split it into fields:
+%% a string (mounted device), 4 integers (kilobytes, used, available
+%% and capacity), skip % sign, (optionally for susv3 can also skip IUsed, IFree
+%% and ICap% fields) then take remaining characters as the mount path
+-spec parse_df(string(), posix | susv3) ->
+    {error, parse_df} | {ok, {integer(), integer(), integer()}, string()}.
+parse_df(Input0, Flavor) ->
+    %% Format of Posix/Linux df output looks like Header + Lines
+    %% Filesystem     1024-blocks     Used Available Capacity Mounted on
+    %% udev               2467108        0   2467108       0% /dev
+    Input1 = parse_df_skip_word(Input0), % skip device path field
+    {KbStr, Input2} = parse_df_take_word(Input1), % take Kb field
+    Input3 = parse_df_skip_word(Input2), % skip Used field
+    Input4 = parse_df_skip_word(Input3), % skip Avail field
+
+    % take Capacity% field; drop a % sign following the capacity
+    {CapacityStr, Input5} = parse_df_take_word_percent(Input4),
+
+    %% Format of OS X/SUSv3 df looks similar to POSIX but has 3 extra columns
+    %% Filesystem 1024-blocks Used Available Capacity iused ifree %iused Mounted
+    %% /dev/disk1   243949060 2380  86690680    65% 2029724 37555    0%  /
+    Input6 = case Flavor of
+                 posix -> Input5;
+                 susv3 -> % there are 3 extra integers we want to skip
+                     Input5a = parse_df_skip_word(Input5), % skip IUsed field
+                     Input5b = parse_df_skip_word(Input5a), % skip IFree field
+                     %% skip the value of ICap + '%' field
+                     {_, Input5c} = parse_df_take_word_percent(Input5b),
+                     Input5c
+             end,
+
+    % path is the remaining string till end of line
+    {MountPath, Input7} = lists:splitwith(fun parse_df_is_not_eol/1, Input6),
+    % Trim the newlines
+    Remaining = lists:dropwhile(fun(X) -> not parse_df_is_not_eol(X) end,
+                                Input7),
+    try
+        Kb = erlang:list_to_integer(KbStr),
+        Capacity = erlang:list_to_integer(CapacityStr),
+        {ok, {Kb, Capacity, MountPath}, Remaining}
+    catch error:badarg ->
+        {error, parse_df}
+    end.
+
 % Parse per SUSv3 specification, notably recent OS X
 check_disks_susv3("", _Threshold) ->
     [];
 check_disks_susv3("\n", _Threshold) ->
     [];
 check_disks_susv3(Str, Threshold) ->
-    case io_lib:fread("~s~d~d~d~d%~d~d~d%~s", Str) of
-    {ok, [_FS, KB, _Used, _Avail, Cap, _IUsed, _IFree, _ICap, MntOn], RestStr} ->
+    case parse_df(Str, susv3) of
+    {ok, {KB, Cap, MntOn}, RestStr} ->
 	    if
 		Cap >= Threshold ->
 		    set_alarm({disk_almost_full, MntOn}, []);
diff --git a/lib/os_mon/src/memsup.erl b/lib/os_mon/src/memsup.erl
index 0a9a883390..95cb798ba5 100644
--- a/lib/os_mon/src/memsup.erl
+++ b/lib/os_mon/src/memsup.erl
@@ -705,7 +705,7 @@ get_os_wordsize_with_uname() ->
 	_         -> 32
     end.
 
-clean_string(String) -> lists:flatten(string:tokens(String,"\r\n\t ")).
+clean_string(String) -> lists:flatten(string:lexemes(String,"\r\n\t ")).
     
 
 %%--Replying to pending clients-----------------------------------------
diff --git a/lib/os_mon/test/disksup_SUITE.erl b/lib/os_mon/test/disksup_SUITE.erl
index ad61985014..d7f2626160 100644
--- a/lib/os_mon/test/disksup_SUITE.erl
+++ b/lib/os_mon/test/disksup_SUITE.erl
@@ -30,7 +30,7 @@
 -export([port/1]).
 -export([terminate/1, unavailable/1, restart/1]).
 -export([otp_5910/1]).
--export([posix_only/1]).
+-export([posix_only/1, parse_df_output_posix/1, parse_df_output_susv3/1]).
 
 init_per_suite(Config) when is_list(Config) ->
     ok = application:start(os_mon),
@@ -59,7 +59,8 @@ suite() ->
 
 all() -> 
     Bugs = [otp_5910],
-    Always = [api, config, alarm, port, posix_only, unavailable] ++ Bugs,
+    Always = [api, config, alarm, port, posix_only, unavailable,
+              parse_df_output_posix, parse_df_output_susv3] ++ Bugs,
     case test_server:os_type() of
 	{unix, _OSname} -> Always;
 	{win32, _OSname} -> Always;
@@ -413,3 +414,36 @@ get_disk_data([{"none",0,0}=E]) -> [E];
 get_disk_data([{_,_,0}|Es]) -> get_disk_data(Es);
 get_disk_data([E|Es]) -> [E|get_disk_data(Es)];
 get_disk_data([]) -> [].
+
+%% @doc Test various expected inputs to 'df' command output (Linux/POSIX)
+parse_df_output_posix(Config) when is_list(Config) ->
+    PosixHdr = "Filesystem     1K-blocks     Used Available Use% Mounted on\n",
+    {error, _} = disksup:parse_df(PosixHdr, posix),
+    {error, _} = disksup:parse_df("", posix),
+    {error, _} = disksup:parse_df("\n\n", posix),
+
+    %% Have a simple example with no funny spaces in mount path
+    Posix1 = "tmpfs             498048     7288    490760   2% /run\n",
+    {ok, {498048, 2, "/run"}, ""} = disksup:parse_df(Posix1, posix),
+
+    %% Have a mount path with some spaces in it
+    Posix2 = "tmpfs             498048     7288    490760   2% /spaces 1 2\n",
+    {ok, {498048, 2, "/spaces 1 2"}, ""} = disksup:parse_df(Posix2, posix).
+
+%% @doc Test various expected inputs to 'df' command output (Darwin/SUSv3)
+parse_df_output_susv3(Config) when is_list(Config) ->
+    DarwinHdr = "Filesystem 1024-blocks      Used Available Capacity " ++
+                "iused      ifree %iused  Mounted on",
+    {error, _} = disksup:parse_df(DarwinHdr, susv3),
+    {error, _} = disksup:parse_df("", susv3),
+    {error, _} = disksup:parse_df("\n\n", susv3),
+
+    %% Have a simple example with no funny spaces in mount path
+    Darwin1 = "/dev/disk1   243949060 157002380  86690680    65% 2029724 " ++
+              "4292937555    0%   /\n",
+    {ok, {243949060, 65, "/"}, ""} = disksup:parse_df(Darwin1, susv3),
+
+    %% Have a mount path with some spaces in it
+    Darwin2 = "/dev/disk1   243949060 157002380  86690680    65% 2029724 " ++
+              "4292937555    0%   /spaces 1 2\n",
+    {ok, {243949060, 65, "/spaces 1 2"}, ""} = disksup:parse_df(Darwin2, susv3).
diff --git a/lib/parsetools/src/leex.erl b/lib/parsetools/src/leex.erl
index e2e7d7359f..8a4a5e8d86 100644
--- a/lib/parsetools/src/leex.erl
+++ b/lib/parsetools/src/leex.erl
@@ -37,7 +37,6 @@
 -import(lists, [member/2,reverse/1,sort/1,delete/2,
                 keysort/2,keydelete/3,
                 map/2,foldl/3,foreach/2,flatmap/2]).
--import(string, [substr/2,substr/3,span/2]).
 -import(ordsets, [is_element/2,add_element/2,union/2]).
 -import(orddict, [store/3]).
 
@@ -251,10 +250,10 @@ is_filename(T) ->
 
 shorten_filename(Name0) ->
     {ok,Cwd} = file:get_cwd(),
-    case lists:prefix(Cwd, Name0) of
-        false -> Name0;
-        true ->
-            case lists:nthtail(length(Cwd), Name0) of
+    case string:prefix(Name0, Cwd) of
+        nomatch -> Name0;
+        Rest ->
+            case unicode:characters_to_list(Rest) of
                 "/"++N -> N;
                 N -> N
             end
@@ -490,12 +489,9 @@ parse_rules_end(_, NextLine, REAs, As, St) ->
 %% action has been read. Keep track of line number.
 
 collect_rule(Ifile, Chars, L0) ->
-    %% Erlang strings are 1 based, but re 0 :-(
-    {match,[{St0,Len}|_]} = re:run(Chars, "[^ \t\r\n]+", [unicode]),
-    St = St0 + 1,
-    %%io:fwrite("RE = ~p~n", [substr(Chars, St, Len)]),
-    case collect_action(Ifile, substr(Chars, St+Len), L0, []) of
-        {ok,[{':',_}|Toks],L1} -> {ok,substr(Chars, St, Len),Toks,L1};
+    {RegExp,Rest} = string:take(Chars, " \t\r\n", true),
+    case collect_action(Ifile, Rest, L0, []) of
+        {ok,[{':',_}|Toks],L1} -> {ok,RegExp,Toks,L1};
         {ok,_,_} -> {error,{L0,leex,bad_rule}};
         {eof,L1} -> {error,{L1,leex,bad_rule}};
         {error,E,_} -> {error,E}
@@ -549,7 +545,7 @@ var_used(Name, Toks) ->
 
 parse_rule_regexp(RE0, [{M,Exp}|Ms], St) ->
     Split= re:split(RE0, "\\{" ++ M ++ "\\}", [{return,list},unicode]),
-    RE1 = string:join(Split, Exp),
+    RE1 = lists:append(lists:join(Exp, Split)),
     parse_rule_regexp(RE1, Ms, St);
 parse_rule_regexp(RE, [], St) ->
     %%io:fwrite("RE = ~p~n", [RE]),
@@ -589,9 +585,9 @@ nextline(Ifile, L, St) ->
         eof -> {eof,L};
         {error, _} -> add_error({L+1, leex, cannot_parse}, St);
         Chars ->
-            case substr(Chars, span(Chars, " \t\n")+1) of
-                [$%|_Rest] -> nextline(Ifile, L+1, St);
-                [] -> nextline(Ifile, L+1, St);
+            case string:take(Chars, " \t\n") of
+                {_, [$%|_Rest]} -> nextline(Ifile, L+1, St);
+                {_, []} -> nextline(Ifile, L+1, St);
                 _Other -> {ok,Chars,L+1}
             end
     end.
@@ -824,7 +820,7 @@ re_char_class(Cs, Cc, _) -> {reverse(Cc),Cs}.   % Preserve order
 %% posix_cc("space" ++ Cs) -> {space,Cs};
 %% posix_cc("upper" ++ Cs) -> {upper,Cs};
 %% posix_cc("xdigit" ++ Cs) -> {xdigit,Cs};
-%% posix_cc(Cs) -> parse_error({posix_cc,substr(Cs, 1, 5)}).
+%% posix_cc(Cs) -> parse_error({posix_cc,string:slice(Cs, 0, 5)}).
 
 escape_char($n) -> $\n;                         % \n = LF
 escape_char($r) -> $\r;                         % \r = CR
@@ -863,7 +859,7 @@ escape_char(C) -> C.                            % Pass it straight through
 %% re_number(Cs, Acc) -> {Acc,Cs}.
 
 string_between(Cs1, Cs2) ->
-    substr(Cs1, 1, length(Cs1)-length(Cs2)).
+    string:slice(Cs1, 0, string:length(Cs1)-string:length(Cs2)).
 
 %% We use standard methods, Thompson's construction and subset
 %% construction, to create first an NFA and then a DFA from the
@@ -1343,7 +1339,7 @@ out_file(Ifile, Ofile, St, DFA, DF, Actions, Code, L) ->
         eof -> output_file_directive(Ofile, St#leex.ifile, L);
         {error, _} -> add_error(St#leex.ifile, {L, leex, cannot_parse}, St);
         Line ->
-            case substr(Line, 1, 5) of
+            case string:slice(Line, 0, 5) of
                 "##mod" -> out_module(Ofile, St);
                 "##cod" -> out_erlang_code(Ofile, St, Code, L);
                 "##dfa" -> out_dfa(Ofile, St, DFA, Code, DF, L);
@@ -1523,7 +1519,7 @@ prep_out_actions(As) ->
                 Name = list_to_atom(lists:concat([yyaction_,A])),
                 [Chars,Len,Line,_,_] = Vars,
                 Args = [V || V <- [Chars,Len,Line], V =/= "_"],
-                ArgsChars = string:join(Args, ", "),
+                ArgsChars = lists:join(", ", Args),
                 {A,Code,Vars,Name,Args,ArgsChars}
         end, As).
 
diff --git a/lib/parsetools/src/yecc.erl b/lib/parsetools/src/yecc.erl
index 36e33b52a4..b4e1cfe5e3 100644
--- a/lib/parsetools/src/yecc.erl
+++ b/lib/parsetools/src/yecc.erl
@@ -365,10 +365,10 @@ is_filename(T) ->
 
 shorten_filename(Name0) ->
     {ok,Cwd} = file:get_cwd(),
-    case lists:prefix(Cwd, Name0) of
-        false -> Name0;
-        true ->
-            case lists:nthtail(length(Cwd), Name0) of
+    case string:prefix(Name0, Cwd) of
+        nomatch -> Name0;
+        Rest ->
+            case unicode:characters_to_list(Rest) of
                 "/"++N -> N;
                 N -> N
             end
@@ -2196,8 +2196,8 @@ output_reduce(St0, State, Terminal,
                 St20;
             true ->
                 Ns = "Nss",
-                Tmp = string:join(lists:duplicate(NmbrOfDaughters - 1, "_"),
-                                  ","),
+                Tmp = lists:join(",",
+                                  lists:duplicate(NmbrOfDaughters - 1, "_")),
                 fwrite(St20, <<" [~s|Nss] = Ss,\n">>, [Tmp])
         end,
     St40 = case tokens(RuleNmbr, St30) of
diff --git a/lib/public_key/src/pubkey_ssh.erl b/lib/public_key/src/pubkey_ssh.erl
index a7d018e440..02c061efc9 100644
--- a/lib/public_key/src/pubkey_ssh.erl
+++ b/lib/public_key/src/pubkey_ssh.erl
@@ -38,6 +38,8 @@
 -define(Empint(X),  (mpint(X))/binary ).
 -define(Estring(X), (string(X))/binary ).
 
+-define(b64enc(X), base64:encode(iolist_to_binary(X)) ).
+-define(b64mime_dec(X), base64:mime_decode(iolist_to_binary(X)) ).
 
 %% Max encoded line length is 72, but conformance examples use 68
 %% Comment from rfc 4716: "The following are some examples of public
@@ -163,7 +165,7 @@ rfc4716_decode_line(Line, Lines, Acc) ->
 	    rfc4716_decode_lines(Lines, [{string_decode(Tag), unicode_decode(Value)} | Acc]);
 	_ ->
 	    {Body, Rest} = join_entry([Line | Lines], []),
-	    {lists:reverse(Acc), rfc4716_pubkey_decode(base64:mime_decode(Body)), Rest}
+	    {lists:reverse(Acc), rfc4716_pubkey_decode(?b64mime_dec(Body)), Rest}
     end.
 
 join_entry([<<"---- END SSH2 PUBLIC KEY ----", _/binary>>| Lines], Entry) ->
@@ -257,11 +259,11 @@ decode_comment(Comment) ->
 
 openssh_pubkey_decode(Type,  Base64Enc) ->
     try
-        <<?DEC_BIN(Type,_TL), Bin/binary>> = base64:mime_decode(Base64Enc),
+        <<?DEC_BIN(Type,_TL), Bin/binary>> = ?b64mime_dec(Base64Enc),
 	ssh2_pubkey_decode(Type,  Bin)
     catch
 	_:_ ->
-	    {Type, base64:mime_decode(Base64Enc)}
+	    {Type, ?b64mime_dec(Base64Enc)}
     end.
 
 
@@ -292,12 +294,12 @@ do_encode(Type, Key, Attributes) ->
 
 rfc4716_encode(Key, [],[]) ->
     iolist_to_binary([begin_marker(),"\n",
-			     split_lines(base64:encode(ssh2_pubkey_encode(Key))),
+			     split_lines(?b64enc(ssh2_pubkey_encode(Key))),
 			     "\n", end_marker(), "\n"]);
 rfc4716_encode(Key, [], [_|_] = Acc) ->
     iolist_to_binary([begin_marker(), "\n",
 			     lists:reverse(Acc),
-			     split_lines(base64:encode(ssh2_pubkey_encode(Key))),
+			     split_lines(?b64enc(ssh2_pubkey_encode(Key))),
 			     "\n", end_marker(), "\n"]);
 rfc4716_encode(Key, [ Header | Headers], Acc) ->
     LinesStr = rfc4716_encode_header(Header),
@@ -326,7 +328,7 @@ rfc4716_encode_value(Value) ->
 
 openssh_encode(openssh_public_key, Key, Attributes) ->
     Comment = proplists:get_value(comment, Attributes, ""),
-    Enc = base64:encode(ssh2_pubkey_encode(Key)),
+    Enc = ?b64enc(ssh2_pubkey_encode(Key)),
     iolist_to_binary([key_type(Key), " ",  Enc,  " ", Comment, "\n"]);
 
 openssh_encode(auth_keys, Key, Attributes) ->
@@ -351,10 +353,10 @@ openssh_encode(known_hosts, Key, Attributes) ->
     end.
 
 openssh_ssh2_auth_keys_encode(undefined, Key, Comment) ->
-    iolist_to_binary([key_type(Key)," ",  base64:encode(ssh2_pubkey_encode(Key)), line_end(Comment)]);
+    iolist_to_binary([key_type(Key)," ",  ?b64enc(ssh2_pubkey_encode(Key)), line_end(Comment)]);
 openssh_ssh2_auth_keys_encode(Options, Key, Comment) ->
     iolist_to_binary([comma_list_encode(Options, []), " ",
-			     key_type(Key)," ", base64:encode(ssh2_pubkey_encode(Key)), line_end(Comment)]).
+			     key_type(Key)," ", ?b64enc(ssh2_pubkey_encode(Key)), line_end(Comment)]).
 
 openssh_ssh1_auth_keys_encode(undefined, Bits,
 			      #'RSAPublicKey'{modulus = N, publicExponent = E},
@@ -369,7 +371,7 @@ openssh_ssh1_auth_keys_encode(Options, Bits,
 
 openssh_ssh2_know_hosts_encode(Hostnames, Key, Comment) ->
     iolist_to_binary([comma_list_encode(Hostnames, []), " ",
-			     key_type(Key)," ",  base64:encode(ssh2_pubkey_encode(Key)), line_end(Comment)]).
+			     key_type(Key)," ",  ?b64enc(ssh2_pubkey_encode(Key)), line_end(Comment)]).
 
 openssh_ssh1_known_hosts_encode(Hostnames, Bits,
 				#'RSAPublicKey'{modulus = N, publicExponent = E},
diff --git a/lib/reltool/src/reltool.hrl b/lib/reltool/src/reltool.hrl
index 9c8aae6b7e..d133762818 100644
--- a/lib/reltool/src/reltool.hrl
+++ b/lib/reltool/src/reltool.hrl
@@ -220,7 +220,8 @@
         {
           name     :: rel_name(),
           vsn      :: rel_vsn(),
-          rel_apps :: [#rel_app{}]
+          rel_apps :: [#rel_app{}],
+          load_dot_erlang = true :: boolean()
 	}).
 
 -record(sys,
@@ -300,6 +301,7 @@
 
 -define(STANDALONE_INCL_SYS_FILTERS,  ["^bin/(erl|epmd)(|\\.exe|\\.ini)\$",
 				       "^bin/start(|_clean).boot\$",
+				       "^bin/no_dot_erlang\\.boot\$",
 				       "^erts.*/bin",
 				       "^lib\$"]).
 -define(STANDALONE_EXCL_SYS_FILTERS,
diff --git a/lib/reltool/src/reltool_mod_win.erl b/lib/reltool/src/reltool_mod_win.erl
index 2d56d74563..dcd802a5de 100644
--- a/lib/reltool/src/reltool_mod_win.erl
+++ b/lib/reltool/src/reltool_mod_win.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2009-2016. All Rights Reserved.
+%% Copyright Ericsson AB 2009-2017. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -833,7 +833,7 @@ load_code(Ed, Code) when is_binary(Code) ->
 
 keyWords() ->
     L = ["after","begin","case","try","cond","catch","andalso","orelse",
-	 "end","fun","if","let","of","query","receive","when","bnot","not",
+	 "end","fun","if","let","of","receive","when","bnot","not",
 	 "div","rem","band","and","bor","bxor","bsl","bsr","or","xor"],
     lists:flatten([K ++ " " || K <- L] ++ [0]).
 
diff --git a/lib/reltool/src/reltool_target.erl b/lib/reltool/src/reltool_target.erl
index 1b1461178e..503e1971b9 100644
--- a/lib/reltool/src/reltool_target.erl
+++ b/lib/reltool/src/reltool_target.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2009-2016. All Rights Reserved.
+%% Copyright Ericsson AB 2009-2017. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -424,7 +424,7 @@ gen_script(Rel, Sys, PathFlag, Variables) ->
             {error, Text}
     end.
 
-do_gen_script(#rel{name = RelName, vsn = RelVsn},
+do_gen_script(#rel{name = RelName, vsn = RelVsn, load_dot_erlang=LoadErlangRc},
               #sys{apps = Apps},
 	      MergedApps,
               PathFlag,
@@ -474,9 +474,11 @@ do_gen_script(#rel{name = RelName, vsn = RelVsn},
              Type =/= none,
              Type =/= load,
              not lists:member(Name, InclApps)],
-
          %% Apply user specific customizations
-         {apply, {c, erlangrc, []}},
+         case LoadErlangRc of
+             true -> {apply, {c, erlangrc, []}};
+             false -> []
+         end,
          {progress, started}
         ],
     {ok, {script, {RelName, RelVsn}, lists:flatten(DeepList)}}.
diff --git a/lib/reltool/src/reltool_utils.erl b/lib/reltool/src/reltool_utils.erl
index 3891b5ae4d..060a0912f9 100644
--- a/lib/reltool/src/reltool_utils.erl
+++ b/lib/reltool/src/reltool_utils.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2009-2016. All Rights Reserved.
+%% Copyright Ericsson AB 2009-2017. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -154,7 +154,12 @@ default_rels() ->
 	  rel_apps = []},
      #rel{name = "start_sasl",
 	  vsn = "1.0",
-	  rel_apps = [#rel_app{name = sasl}]}
+          rel_apps = [#rel_app{name = sasl}]},
+     #rel{name = "no_dot_erlang", %% Needed by escript and erlc
+          vsn = "1.0",
+          rel_apps = [],
+          load_dot_erlang = false
+         }
     ].
 
 choose_default(Tag, Profile, InclDefs)
diff --git a/lib/reltool/test/reltool_server_SUITE.erl b/lib/reltool/test/reltool_server_SUITE.erl
index 49efe5aeda..3622f6650c 100644
--- a/lib/reltool/test/reltool_server_SUITE.erl
+++ b/lib/reltool/test/reltool_server_SUITE.erl
@@ -247,6 +247,7 @@ get_config(_Config) ->
 		    {app,stdlib,[{incl_cond,include},{vsn,undefined},
 				 {lib_dir,StdLibDir}]},
 		    {boot_rel,"start_clean"},
+                    {rel,"no_dot_erlang","1.0",[]},
 		    {rel,"start_clean","1.0",[]},
 		    {rel,"start_sasl","1.0",[sasl]},
 		    {emu_name,"beam"},
@@ -277,6 +278,7 @@ get_config(_Config) ->
 		    {app,stdlib,[{incl_cond,include},{vsn,StdVsn},
 				 {lib_dir,StdLibDir},{mod,_,[]}|_]},
 		    {boot_rel,"start_clean"},
+                    {rel,"no_dot_erlang","1.0",[]},
 		    {rel,"start_clean","1.0",[]},
 		    {rel,"start_sasl","1.0",[sasl]},
 		    {emu_name,"beam"},
@@ -2104,6 +2106,7 @@ save_config(Config) ->
 		     {app,stdlib,[{incl_cond,include},{vsn,undefined},
 				  {lib_dir,undefined}]},
 		     {boot_rel,"start_clean"},
+                     {rel,"no_dot_erlang","1.0",[]},
 		     {rel,"start_clean","1.0",[]},
 		     {rel,"start_sasl","1.0",[sasl]},
 		     {emu_name,"beam"},
@@ -2144,6 +2147,7 @@ save_config(Config) ->
 		     {app,stdlib,[{incl_cond,include},{vsn,StdVsn},
 				  {lib_dir,StdLibDir},{mod,_,[]}|_]},
 		     {boot_rel,"start_clean"},
+                     {rel,"no_dot_erlang","1.0",[]},
 		     {rel,"start_clean","1.0",[]},
 		     {rel,"start_sasl","1.0",[sasl]},
 		     {emu_name,"beam"},
@@ -2545,7 +2549,7 @@ undefined_regexp(_Config) ->
 %% Library functions
 
 erl_libs() ->
-    string:tokens(os:getenv("ERL_LIBS", ""), ":;").
+    string:lexemes(os:getenv("ERL_LIBS", ""), ":;").
 
 datadir(Config) ->
     %% Removes the trailing slash...
@@ -2555,7 +2559,7 @@ latest(App) ->
     AppStr = atom_to_list(App),
     AppDirs = filelib:wildcard(filename:join(code:lib_dir(),AppStr++"-*")),
     [LatestAppDir|_] = lists:reverse(AppDirs),
-    [_,Vsn] = string:tokens(filename:basename(LatestAppDir),"-"),
+    [_,Vsn] = string:lexemes(filename:basename(LatestAppDir),"-"),
     Vsn.
 
 rm_missing_app(Apps) ->
@@ -2631,16 +2635,11 @@ os_cmd(Cmd) when is_list(Cmd) ->
         Return->
             %% Find the position of the status code wich is last in the string
             %% prepended with #
-            case string:rchr(Return, $#) of
-                
-                %% This happens only if the sh command pipe is somehow interrupted
-                0->
-                {98, Return};
-                
-                Position->
-                Result = string:left(Return,Position - 1),
-                Status = string:substr(Return,Position + 1, length(Return) - Position - 1),
-                {list_to_integer(Status), Result}
+            case string:split(Return, "$#", trailing) of
+                [_] -> %% This happens only if the sh command pipe is somehow interrupted
+                    {98, Return};
+                [Result, Status0] ->
+                    {list_to_integer(string:trim(Status0)), Result}
             end
     end.
 
diff --git a/lib/runtime_tools/doc/src/LTTng.xml b/lib/runtime_tools/doc/src/LTTng.xml
index 392d54857c..93937b3fdc 100644
--- a/lib/runtime_tools/doc/src/LTTng.xml
+++ b/lib/runtime_tools/doc/src/LTTng.xml
@@ -134,7 +134,7 @@ $ make </code>
         <p><em>port_open</em></p>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
         </list>
         <p>
@@ -323,7 +323,7 @@ $ make </code>
 
         <p><em>driver_init</em></p>
         <list type="bulleted">
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
             <item><c>major : integer</c> :: Major version. Ex. <c>3</c></item>
             <item><c>minor : integer</c> :: Minor version. Ex. <c>1</c></item>
             <item><c>flags : integer</c> :: Flags. Ex. <c>1</c></item>
@@ -334,7 +334,7 @@ $ make </code>
         <p><em>driver_start</em></p>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
         </list>
         <p>Example:</p>
@@ -344,7 +344,7 @@ $ make </code>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
             <item><c>bytes : integer</c> :: Size of data returned. Ex. <c>82</c></item>
         </list>
         <p>Example:</p>
@@ -354,7 +354,7 @@ $ make </code>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
             <item><c>bytes : integer</c> :: Size of data returned. Ex. <c>82</c></item>
         </list>
         <p>Example:</p>
@@ -364,7 +364,7 @@ $ make </code>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
         </list>
         <p>Example:</p>
         <code type="none">driver_ready_input: { cpu_id = 5 }, { pid = "&lt;0.189.0&gt;", port = "#Port&lt;0.3637&gt;", driver = "inet_gethost 4 " }</code>
@@ -373,7 +373,7 @@ $ make </code>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
         </list>
         <p>Example:</p>
         <code type="none">driver_ready_output: { cpu_id = 5 }, { pid = "&lt;0.194.0&gt;", port = "#Port&lt;0.3663&gt;", driver = "tcp_inet" }</code>
@@ -382,14 +382,14 @@ $ make </code>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
         </list>
         <p>Example:</p>
         <code type="none">driver_timeout: { cpu_id = 5 }, { pid = "&lt;0.196.0&gt;", port = "#Port&lt;0.3664&gt;", driver = "tcp_inet" }</code>
 
         <p><em>driver_stop_select</em></p>
         <list type="bulleted">
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
         </list>
         <p>Example:</p>
         <code type="none">driver_stop_select: { cpu_id = 5 }, { driver = "unknown" }</code>
@@ -398,7 +398,7 @@ $ make </code>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
         </list>
         <p>Example:</p>
         <code type="none">driver_flush: { cpu_id = 7 }, { pid = "&lt;0.204.0&gt;", port = "#Port&lt;0.3686&gt;", driver = "tcp_inet" }</code>
@@ -407,32 +407,32 @@ $ make </code>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
         </list>
         <p>Example:</p>
-        <code type="none">driver_stop: { cpu_id = 5 }, { pid = "[]", port = "#Port&lt;0.3673&gt;", driver = "efile" }</code>
+        <code type="none">driver_stop: { cpu_id = 5 }, { pid = "[]", port = "#Port&lt;0.3673&gt;", driver = "tcp_inet" }</code>
 
         <p><em>driver_process_exit</em></p>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
         </list>
 
         <p><em>driver_ready_async</em></p>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
         </list>
         <p>Example:</p>
-        <code type="none">driver_ready_async: { cpu_id = 3 }, { pid = "&lt;0.181.0&gt;", port = "#Port&lt;0.3622&gt;", driver = "efile" }</code>
+        <code type="none">driver_ready_async: { cpu_id = 3 }, { pid = "&lt;0.181.0&gt;", port = "#Port&lt;0.3622&gt;", driver = "tcp_inet" }</code>
 
         <p><em>driver_call</em></p>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
             <item><c>command : integer</c> :: Command integer. Ex. <c>1</c></item>
             <item><c>bytes : integer</c> :: Size of data returned. Ex. <c>82</c></item>
         </list>
@@ -443,7 +443,7 @@ $ make </code>
         <list type="bulleted">
             <item><c>pid : string</c> :: Process ID. Ex. <c>"&lt;0.131.0&gt;"</c></item>
             <item><c>port : string</c> :: Port ID. Ex. <c>"#Port&lt;0.1031&gt;"</c></item>
-            <item><c>driver : string</c> :: Driver name. Ex. <c>"efile"</c></item>
+            <item><c>driver : string</c> :: Driver name. Ex. <c>"tcp_inet"</c></item>
             <item><c>command : integer</c> :: Command integer. Ex. <c>1</c></item>
             <item><c>bytes : integer</c> :: Size of data returned. Ex. <c>82</c></item>
         </list>
diff --git a/lib/runtime_tools/examples/efile_drv.d b/lib/runtime_tools/examples/efile_drv.d
deleted file mode 100644
index a470518dd9..0000000000
--- a/lib/runtime_tools/examples/efile_drv.d
+++ /dev/null
@@ -1,105 +0,0 @@
-/* example usage: dtrace -q -s /path/to/efile_drv.d */
-/*
- * %CopyrightBegin%
- *
- * Copyright Scott Lystig Fritchie 2011-2016. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * %CopyrightEnd%
- */
-
-BEGIN
-{
-    op_map[1] = "OPEN";
-    op_map[2] = "READ";
-    op_map[3] = "LSEEK";
-    op_map[4] = "WRITE";
-    op_map[5] = "FSTAT";
-    op_map[6] = "PWD";
-    op_map[7] = "READDIR";
-    op_map[8] = "CHDIR";
-    op_map[9] = "FSYNC";
-    op_map[10] = "MKDIR";
-    op_map[11] = "DELETE";
-    op_map[12] = "RENAME";
-    op_map[13] = "RMDIR";
-    op_map[14] = "TRUNCATE";
-    op_map[15] = "READ_FILE";
-    op_map[16] = "WRITE_INFO";
-    op_map[19] = "LSTAT";
-    op_map[20] = "READLINK";
-    op_map[21] = "LINK";
-    op_map[22] = "SYMLINK";
-    op_map[23] = "CLOSE";
-    op_map[24] = "PWRITEV";
-    op_map[25] = "PREADV";
-    op_map[26] = "SETOPT";
-    op_map[27] = "IPREAD";
-    op_map[28] = "ALTNAME";
-    op_map[29] = "READ_LINE";
-    op_map[30] = "FDATASYNC";
-    op_map[31] = "FADVISE";
-}
-
-erlang*:::aio_pool-add
-{
-    printf("async I/O pool port %s queue len %d\n", copyinstr(arg0), arg1);
-}
-
-erlang*:::aio_pool-get
-{
-    printf("async I/O pool port %s queue len %d\n", copyinstr(arg0), arg1);
-}
-
-erlang*:::efile_drv-entry
-{
-    printf("efile_drv enter tag={%d,%d} %s%s | %s (%d) | args: %s %s , %d %d (port %s)\n",
-	   arg0, arg1,
-           arg2 == NULL ? "" : "user tag ",
-           arg2 == NULL ? "" : copyinstr(arg2),
-           op_map[arg3], arg3,
-	   arg4 == NULL ? "" : copyinstr(arg4),
-	   arg5 == NULL ? "" : copyinstr(arg5), arg6, arg7,
-           /* NOTE: port name in args[10] is experimental */
-           (args[10] == NULL) ? 
-	       "?" : copyinstr((user_addr_t) args[10]));
-}
-
-erlang*:::efile_drv-int*
-{
-    printf("async I/O worker tag={%d,%d} | %s (%d) | %s\n",
-           arg0, arg1, op_map[arg2], arg2, probename);
-}
-
-/* efile_drv-return error case */
-erlang*:::efile_drv-return
-/arg4 == 0/
-{
-    printf("efile_drv return tag={%d,%d} %s%s | %s (%d) | errno %d\n",
-           arg0, arg1,
-           arg2 == NULL ? "" : "user tag ",
-           arg2 == NULL ? "" : copyinstr(arg2),
-           op_map[arg3], arg3,
-           arg5);
-}
-
-/* efile_drv-return success case */
-erlang*:::efile_drv-return
-/arg4 != 0/
-{
-    printf("efile_drv return tag={%d,%d} %s | %s (%d) ok\n",
-           arg0, arg1,
-           arg2 == NULL ? "" : copyinstr(arg2),
-           op_map[arg3], arg3);
-}
diff --git a/lib/runtime_tools/examples/efile_drv.systemtap b/lib/runtime_tools/examples/efile_drv.systemtap
deleted file mode 100644
index 29c3637e10..0000000000
--- a/lib/runtime_tools/examples/efile_drv.systemtap
+++ /dev/null
@@ -1,113 +0,0 @@
-/*
- * %CopyrightBegin%
- *
- * Copyright Scott Lystig Fritchie and Andreas Schultz, 2011-2016. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * %CopyrightEnd%
- */
-/*
- * Note: This file assumes that you're using the non-SMP-enabled Erlang
- *       virtual machine, "beam".  The SMP-enabled VM is called "beam.smp".
- *       Note that other variations of the virtual machine also have
- *       different names, e.g. the debug build of the SMP-enabled VM
- *       is "beam.debug.smp".
- *
- *       To use a different virtual machine, replace each instance of
- *       "beam" with "beam.smp" or the VM name appropriate to your
- *       environment.
- */
-
-probe begin
-{
-    op_map[1] = "OPEN";
-    op_map[2] = "READ";
-    op_map[3] = "LSEEK";
-    op_map[4] = "WRITE";
-    op_map[5] = "FSTAT";
-    op_map[6] = "PWD";
-    op_map[7] = "READDIR";
-    op_map[8] = "CHDIR";
-    op_map[9] = "FSYNC";
-    op_map[10] = "MKDIR";
-    op_map[11] = "DELETE";
-    op_map[12] = "RENAME";
-    op_map[13] = "RMDIR";
-    op_map[14] = "TRUNCATE";
-    op_map[15] = "READ_FILE";
-    op_map[16] = "WRITE_INFO";
-    op_map[19] = "LSTAT";
-    op_map[20] = "READLINK";
-    op_map[21] = "LINK";
-    op_map[22] = "SYMLINK";
-    op_map[23] = "CLOSE";
-    op_map[24] = "PWRITEV";
-    op_map[25] = "PREADV";
-    op_map[26] = "SETOPT";
-    op_map[27] = "IPREAD";
-    op_map[28] = "ALTNAME";
-    op_map[29] = "READ_LINE";
-    op_map[30] = "FDATASYNC";
-    op_map[31] = "FADVISE";
-}
-
-probe process("beam").mark("aio_pool-add")
-{
-    printf("async I/O pool port %s queue len %d\n", user_string($arg1), $arg2);
-}
-
-probe process("beam").mark("aio_pool-get")
-{
-    printf("async I/O pool port %s queue len %d\n", user_string($arg1), $arg2);
-}
-
-probe process("beam").mark("efile_drv-entry")
-{
-    printf("efile_drv enter tag={%d,%d} %s%s | %s (%d) | args: %s %s , %d %d (port %s)\n",
-	   $arg1, $arg2,
-           $arg3 == NULL ? "" : "user tag ",
-           $arg3 == NULL ? "" : user_string($arg3),
-           op_map[$arg4], $arg4,
-	   $arg5 == NULL ? "" : user_string($arg5),
-	   $arg6 == NULL ? "" : user_string($arg6), $arg7, $arg8,
-           /* NOTE: port name in $arg[11] is experimental */
-           user_string($arg11))
-}
-
-probe process("beam").mark("efile_drv-int*")
-{
-    printf("async I/O worker tag={%d,%d} | %s (%d) | %s\n",
-           $arg1, $arg2, op_map[$arg3], $arg3, probefunc());
-}
-
-probe process("beam").mark("efile_drv-return")
-{
-    if ($arg5 == 0) {
-       /* efile_drv-return error case */
-       printf("efile_drv return tag={%d,%d} %s%s | %s (%d) | errno %d\n",
-           $arg1, $arg2,
-           $arg3 == NULL ? "" : "user tag ",
-           $arg3 == NULL ? "" : user_string($arg3),
-           op_map[$arg4], $arg4,
-           $arg6);
-    } else {
-       /* efile_drv-return success case */
-       printf("efile_drv return tag={%d,%d} %s | %s (%d) ok\n",
-           $arg1, $arg2,
-           $arg3 == NULL ? "" : user_string($arg3),
-           op_map[$arg4], $arg4);
-    }
-}
-
-global op_map;
diff --git a/lib/runtime_tools/src/erts_alloc_config.erl b/lib/runtime_tools/src/erts_alloc_config.erl
index 514530332c..342363d08d 100644
--- a/lib/runtime_tools/src/erts_alloc_config.erl
+++ b/lib/runtime_tools/src/erts_alloc_config.erl
@@ -621,7 +621,7 @@ format_header(FTO) ->
 	[Y, Mo, D, H, Mi, S]),
     fcp(FTO,
 	"~s was used when generating the configuration.",
-	[string:strip(erlang:system_info(system_version), both, $\n)]),
+	[string:trim(erlang:system_info(system_version), both, "$\n")]),
     case erlang:system_info(schedulers) of
 	1 -> ok;
 	Schdlrs ->
@@ -698,28 +698,32 @@ fc(IODev, Frmt, Args) ->
     fc(IODev, lists:flatten(io_lib:format(Frmt, Args))).
 
 fc(IODev, String) ->
-    fc_aux(IODev, string:tokens(String, " "), 0).
+    fc_aux(IODev, string:lexemes(String, " "), 0).
 
 fc_aux(_IODev, [], 0) ->
     ok;
 fc_aux(IODev, [], _Len) ->
     format(IODev, "~n");
 fc_aux(IODev, [T|Ts], 0) ->
-    Len = 2 + length(T),
+    Len = 2 + string:length(T),
     format(IODev, "# ~s", [T]),
     fc_aux(IODev, Ts, Len);
-fc_aux(IODev, [T|_Ts] = ATs, Len) when (length(T) + Len) >= ?PRINT_WITDH ->
-    format(IODev, "~n"),
-    fc_aux(IODev, ATs, 0);
-fc_aux(IODev, [T|Ts], Len) ->
-    NewLen = Len + 1 + length(T),
-    format(IODev, " ~s", [T]),
-    fc_aux(IODev, Ts, NewLen).
+fc_aux(IODev, [T|Ts] = ATs, Len) ->
+    TLength = string:length(T),
+    case (TLength + Len) >= ?PRINT_WITDH of
+        true ->
+            format(IODev, "~n"),
+            fc_aux(IODev, ATs, 0);
+        false ->
+            NewLen = Len + 1 + TLength,
+            format(IODev, " ~s", [T]),
+            fc_aux(IODev, Ts, NewLen)
+    end.
 
 %% fcl: format comment line
 fcl(FTO) ->
     EndStr = "# ",
-    Precision = length(EndStr),
+    Precision = string:length(EndStr),
     FieldWidth = -1*(?PRINT_WITDH),
     format(FTO, "~*.*.*s~n", [FieldWidth, Precision, $-, EndStr]).
 
@@ -727,6 +731,6 @@ fcl(FTO, A) when is_atom(A) ->
     fcl(FTO, atom_to_list(A));
 fcl(FTO, Str) when is_list(Str) ->
     Str2 = "# --- " ++ Str ++ " ",
-    Precision = length(Str2),
+    Precision = string:length(Str2),
     FieldWidth = -1*(?PRINT_WITDH),
     format(FTO, "~*.*.*s~n", [FieldWidth, Precision, $-, Str2]).
diff --git a/lib/runtime_tools/src/msacc.erl b/lib/runtime_tools/src/msacc.erl
index 0d9b2690e5..37887cee72 100644
--- a/lib/runtime_tools/src/msacc.erl
+++ b/lib/runtime_tools/src/msacc.erl
@@ -46,7 +46,8 @@
                                                        system := float()}}.
 
 
--type msacc_type() :: scheduler | aux | async.
+-type msacc_type() :: aux | async | dirty_cpu_scheduler
+                    | dirty_io_scheduler | poll | scheduler.
 -type msacc_id() :: non_neg_integer().
 -type msacc_state() :: alloc | aux | bif | busy_wait | check_io |
                        emulator | ets | gc | gc_fullsweep | nif |
diff --git a/lib/runtime_tools/src/observer_backend.erl b/lib/runtime_tools/src/observer_backend.erl
index 1b075a507d..a1edde8516 100644
--- a/lib/runtime_tools/src/observer_backend.erl
+++ b/lib/runtime_tools/src/observer_backend.erl
@@ -293,7 +293,7 @@ fetch_stats_loop(Parent, Time) ->
     erlang:system_flag(scheduler_wall_time, true),
     receive
 	_Msg ->
-	    %% erlang:system_flag(scheduler_wall_time, false)
+	    erlang:system_flag(scheduler_wall_time, false),
 	    ok
     after Time ->
 	    _M = Parent ! {stats, 1,
@@ -340,7 +340,6 @@ etop_collect(Collector) ->
 
     case SchedulerWallTime of
 	undefined ->
-            erlang:system_flag(scheduler_wall_time,true),
             spawn(fun() -> flag_holder_proc(Collector) end),
             ok;
 	_ ->
@@ -348,10 +347,11 @@ etop_collect(Collector) ->
     end.
 
 flag_holder_proc(Collector) ->
+    erlang:system_flag(scheduler_wall_time,true),
     Ref = erlang:monitor(process,Collector),
     receive
 	{'DOWN',Ref,_,_,_} ->
-	    %% erlang:system_flag(scheduler_wall_time,false)
+	    erlang:system_flag(scheduler_wall_time,false),
 	    ok
     end.
 
diff --git a/lib/runtime_tools/src/system_information.erl b/lib/runtime_tools/src/system_information.erl
index df25297eb9..92109c9a74 100644
--- a/lib/runtime_tools/src/system_information.erl
+++ b/lib/runtime_tools/src/system_information.erl
@@ -590,12 +590,12 @@ vsnstr2vsn(VsnStr) ->
     list_to_tuple(lists:map(fun (Part) ->
 				    list_to_integer(Part)
 			    end,
-			    string:tokens(VsnStr, "."))).
+			    string:lexemes(VsnStr, "."))).
 
 rtdepstrs2rtdeps([]) ->
     [];
 rtdepstrs2rtdeps([RTDep | RTDeps]) ->
-    [AppStr, VsnStr] = string:tokens(RTDep, "-"),
+    [AppStr, VsnStr] = string:lexemes(RTDep, "-"),
     [{list_to_atom(AppStr), vsnstr2vsn(VsnStr)} | rtdepstrs2rtdeps(RTDeps)].
 
 build_app_table([], AppTab) ->
diff --git a/lib/runtime_tools/test/dbg_SUITE.erl b/lib/runtime_tools/test/dbg_SUITE.erl
index 4b0864858c..cfe8412e33 100644
--- a/lib/runtime_tools/test/dbg_SUITE.erl
+++ b/lib/runtime_tools/test/dbg_SUITE.erl
@@ -23,7 +23,7 @@
 -export([all/0, suite/0,
          big/1, tiny/1, simple/1, message/1, distributed/1, port/1,
 	 send/1, recv/1,
-         ip_port/1, file_port/1, file_port2/1, file_port_schedfix/1,
+         ip_port/1, file_port/1, file_port2/1,
          ip_port_busy/1, wrap_port/1, wrap_port_time/1,
          with_seq_trace/1, dead_suspend/1, local_trace/1,
          saved_patterns/1, tracer_exit_on_stop/1,
@@ -41,7 +41,7 @@ suite() ->
 all() -> 
     [big, tiny, simple, message, distributed, port, ip_port,
      send, recv,
-     file_port, file_port2, file_port_schedfix, ip_port_busy,
+     file_port, file_port2, ip_port_busy,
      wrap_port, wrap_port_time, with_seq_trace, dead_suspend,
      local_trace, saved_patterns, tracer_exit_on_stop,
      erl_tracer, distributed_erl_tracer].
@@ -623,99 +623,6 @@ file_port2(Config) when is_list(Config) ->
     end,
     ok.
 
-%% Test that the scheduling timestamp fix for trace flag 'running' works.
-file_port_schedfix(Config) when is_list(Config) ->
-    case (catch erlang:system_info(smp_support)) of
-        true ->
-            {skip, "No schedule fix on SMP"};
-        _ ->
-            try
-                file_port_schedfix1(Config)
-            after
-                dbg:stop()
-            end
-    end.
-file_port_schedfix1(Config) when is_list(Config) ->
-    stop(),
-    {A,B,C} = erlang:now(),
-    FTMP =  atom_to_list(?MODULE) ++ integer_to_list(A) ++
-    "-" ++ integer_to_list(B) ++ "-" ++ integer_to_list(C),
-    FName = filename:join([proplists:get_value(data_dir, Config), FTMP]),
-    %%
-    Port = dbg:trace_port(file, {FName, wrap, ".wraplog", 8*1024, 4}),
-    {ok, _} = dbg:tracer(port, Port),
-    {ok,[{matched,_node,0}]} = dbg:p(new,[running,procs,send,timestamp]),
-    %%
-    %% Generate the trace data
-    %%
-    %% This starts 3 processes that sends a message to each other in a ring,
-    %% 4 laps. Prior to sending the message to the next in the ring, each
-    %% process send 8 messages to itself, just to generate some trace data,
-    %% and to lower the possibility that the trace log wraps just after
-    %% a schedule out message (which would not burden any process and hence
-    %% not show up in the result)
-    %%
-    %% The wrap file trace is used because it burns a lot of time when the
-    %% driver swaps files, a lot more than the regular file trace. The test
-    %% case is dimensioned so that the log fills two files and just starts
-    %% on the third (out of four wrap files). This gives two file swaps,
-    %% and there are three processes, so one process will NOT be burdened.
-    %% The criterion for trace success is then that the max process
-    %% execution time must not be more than twice the min process
-    %% execution time. Wallclock. A normal result is about 10 times more
-    %% without schedule in - schedule out compensation (OTP-3938).
-    %%
-    ok = token_volleyball(3, 4, 8),
-    %%
-    {ok,[{matched,_,_}]} = dbg:p(all, [clear]),
-    stop(),
-    %%
-    %% Get the trace result
-    %%
-    Tag = make_ref(),
-    dbg:trace_client(file, {FName, wrap, ".wraplog"},
-                     {fun schedstat_handler/2, {self(), Tag, []}}),
-    Result =
-    receive
-        {Tag, D} ->
-            lists:map(
-              fun({Pid, {A1, B1, C1}}) ->
-                      {Pid, C1/1000000 + B1 + A1*1000000}
-              end,
-              D)
-    end,
-    ok = io:format("Result=~p", [Result]),
-    %    erlang:display({?MODULE, ?LINE, Result}),
-    %%
-    %% Analyze the result
-    %%
-    {Min, Max} = lists:foldl(fun({_Pid, M}, {Mi, Ma}) ->
-                                     {if M < Mi -> M; true -> Mi end,
-                                      if M > Ma -> M; true -> Ma end}
-                             end,
-                             {void, 0},
-                             Result),
-    % More PaN debug
-    io:format("Min = ~f, Max = ~f~n",[Min,Max]),
-    %%
-    %% Cleanup
-    %%
-    ToBeDeleted = filelib:wildcard(FName++"*"++".wraplog"),
-    lists:map(fun file:delete/1, ToBeDeleted),
-    %    io:format("ToBeDeleted=~p", [ToBeDeleted]),
-    %%
-    %% Present the result
-    %%
-    P = (Max / Min - 1) * 100,
-    BottomLine = lists:flatten(io_lib:format("~.2f %", [P])),
-    if P > 100 ->
-           Reason = {BottomLine, '>', "100%"},
-           erlang:display({file_port_schedfix, fail, Reason}),
-           ct:fail(Reason);
-       true ->
-           {comment, BottomLine}
-    end.
-
 %% Test tracing to wrapping file port
 wrap_port(Config) when is_list(Config) ->
     Self = self(),
diff --git a/lib/runtime_tools/test/dyntrace_SUITE.erl b/lib/runtime_tools/test/dyntrace_SUITE.erl
index 7be2f49a8b..7ffbe54446 100644
--- a/lib/runtime_tools/test/dyntrace_SUITE.erl
+++ b/lib/runtime_tools/test/dyntrace_SUITE.erl
@@ -51,11 +51,7 @@ init_per_suite(Config) ->
 	case erlang:system_info(debug_compiled) of
 	    false -> "";
 	    true -> ".debug"
-	end ++
-	case erlang:system_info(smp_support) of
-	    false -> "";
-	    true -> ".smp"
-	end,
+	end ++ ".smp",
     [{emu_name,N}|Config].
 
 end_per_suite(_Config) ->
diff --git a/lib/sasl/src/Makefile b/lib/sasl/src/Makefile
index ac7ee51100..45cd814bf8 100644
--- a/lib/sasl/src/Makefile
+++ b/lib/sasl/src/Makefile
@@ -37,7 +37,7 @@ RELSYSDIR = $(RELEASE_PATH)/lib/sasl-$(VSN)
 MODULES= alarm_handler sasl sasl_report \
 	sasl_report_file_h sasl_report_tty_h format_lib_supp \
 	misc_supp rb rb_format_supp release_handler \
-	release_handler_1 si si_sasl_supp systools \
+	release_handler_1 systools \
 	systools_make systools_rc systools_relup systools_lib \
 	erlsrv
 
diff --git a/lib/sasl/src/erlsrv.erl b/lib/sasl/src/erlsrv.erl
index 29d40d362f..e0bbd37ee3 100644
--- a/lib/sasl/src/erlsrv.erl
+++ b/lib/sasl/src/erlsrv.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1998-2016. All Rights Reserved.
+%% Copyright Ericsson AB 1998-2017. All Rights Reserved.
 %% 
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -34,7 +34,7 @@ erlsrv(EVer) ->
     filename:join([Root, "erts-" ++ EVer, "bin", "erlsrv.exe"]).
 
 current_version() ->
-    hd(string:tokens(erlang:system_info(version),"_ ")).
+    hd(string:lexemes(erlang:system_info(version),"_ ")).
 
 %%% Returns {ok, Output} | failed | {error, Reason}
 run_erlsrv(Command) ->
@@ -107,7 +107,7 @@ get_all_services() ->
 	    [];
 	{ok, [_H|T]} ->
 	    F = fun(X) ->
-			hd(string:tokens(X,"\t "))
+			hd(string:lexemes(X,"\t "))
 		end,
 	    lists:map(F,T);
 	_ ->
@@ -191,8 +191,8 @@ get_service(EVer, ServiceName) ->
 	    %%% have in the environment list...
 	    EnvParts = lists:map(
 			 fun(S) ->
-				 X = string:strip(S,left,$\t),
-				 case hd(string:tokens(X,"=")) of
+				 X = string:trim(S, leading, "$\t"),
+				 case hd(string:lexemes(X,"=")) of
 				     X ->
 					 %% Can this happen?
 					 {X,""};
@@ -371,7 +371,7 @@ split_arglist([H|T]) ->
 parse_arglist(Str) ->
     lists:reverse(parse_arglist(Str,[])).
 parse_arglist(Str,Accum) ->
-    Stripped = string:strip(Str,left),
+    Stripped = string:trim(Str, leading),
     case length(Stripped) of
 	0 ->
 	    Accum;
@@ -432,14 +432,9 @@ split_by_env(Data) ->
 			
 
 splitline(Line) ->
-    case string:chr(Line,$:) of
-	0 ->
+    case string:split(Line, ":") of
+        [_] ->
 	    {Line, ""};
-	N ->
-	    case length(string:substr(Line,N)) of
-		1 ->
-		    {string:substr(Line,1,N-1),""};
-		_ ->
-		    {string:substr(Line,1,N-1),string:substr(Line,N+2)}
-	    end
+        [N, V] ->
+            {N, string:slice(V, 1)}
     end.
diff --git a/lib/sasl/src/format_lib_supp.erl b/lib/sasl/src/format_lib_supp.erl
index 00ce1b4e33..2d37dfe117 100644
--- a/lib/sasl/src/format_lib_supp.erl
+++ b/lib/sasl/src/format_lib_supp.erl
@@ -102,13 +102,13 @@ print_newlines(Device, N) when N > 0 ->
 print_one_line(Device, Line, Key, Value) ->
     Modifier = misc_supp:modifier(Device),
     StrKey = term_to_string(Key,Modifier),
-    KeyLen = lists:min([length(StrKey), Line]),
+    KeyLen = lists:min([string:length(StrKey), Line]),
     ValueLen = Line - KeyLen,
     Format1 = lists:concat(["~-", KeyLen, Modifier, "s"]),
     Format2 = lists:concat(["~", ValueLen, Modifier, "s~n"]),
     io:format(Device, Format1, [StrKey]),
     Try = term_to_string(Value,Modifier),
-    Length = length(Try),
+    Length = string:length(Try),
     if
 	Length < ValueLen ->
 	    io:format(Device, Format2, [Try]);
@@ -119,7 +119,7 @@ print_one_line(Device, Line, Key, Value) ->
     end.
 
 term_to_string(Value,Modifier) ->
-    lists:flatten(io_lib:format(get_format(Value,Modifier), [Value])).
+    io_lib:format(get_format(Value,Modifier), [Value]).
 
 get_format([],_) ->
     "~p";
diff --git a/lib/sasl/src/rb.erl b/lib/sasl/src/rb.erl
index 6595d29a9c..28829132a1 100644
--- a/lib/sasl/src/rb.erl
+++ b/lib/sasl/src/rb.erl
@@ -586,14 +586,14 @@ find_widths([], _Modifier, DescrWidth, DateWidth, Data) ->
     {DescrWidth+1, DateWidth+1, lists:reverse(Data)};
 find_widths([H|T], Modifier, DescrWidth, DateWidth, Data) ->
     DescrTerm = element(3,H),
-    Descr = lists:flatten(io_lib:format("~"++Modifier++"w", [DescrTerm])),
-    DescrTry = length(Descr),
+    Descr = io_lib:format("~"++Modifier++"w", [DescrTerm]),
+    DescrTry = string:length(Descr),
     NewDescrWidth =
         if
             DescrTry > DescrWidth -> DescrTry;
             true -> DescrWidth
         end,
-    DateTry = length(element(4, H)),
+    DateTry = string:length(element(4, H)),
     NewDateWitdh =
         if
             DateTry > DateWidth -> DateTry;
diff --git a/lib/sasl/src/rb_format_supp.erl b/lib/sasl/src/rb_format_supp.erl
index 1eda43dae4..b5b7aba151 100644
--- a/lib/sasl/src/rb_format_supp.erl
+++ b/lib/sasl/src/rb_format_supp.erl
@@ -108,7 +108,7 @@ print(Date, Report, Device) ->
 
 format_h(Line, Header, Pid, Date) ->
     NHeader = lists:flatten(io_lib:format("~s  ~w", [Header, Pid])), 
-    DateLen = length(Date),
+    DateLen = string:length(Date),
     HeaderLen = Line - DateLen,
     Format = lists:concat(["~-", HeaderLen, "s~", DateLen, "s"]),
     io_lib:format(Format, [NHeader, Date]).
diff --git a/lib/sasl/src/release_handler.erl b/lib/sasl/src/release_handler.erl
index d0a7c7332d..bfa49fc05d 100644
--- a/lib/sasl/src/release_handler.erl
+++ b/lib/sasl/src/release_handler.erl
@@ -420,7 +420,7 @@ upgrade_app(App, NewDir) ->
 %%          located in the ebin dir of the _current_ version
 %%-----------------------------------------------------------------
 downgrade_app(App, OldDir) ->
-    case string:tokens(filename:basename(OldDir), "-") of
+    case string:lexemes(filename:basename(OldDir), "-") of
 	[_AppS, OldVsn] ->
 	    downgrade_app(App, OldVsn, OldDir);
 	_ ->
@@ -1174,8 +1174,8 @@ new_emulator_rm_tmp_release(_,_,_,_,Releases,_) ->
 
 %% Rename the tempoarary service (for erts ugprade) to the real ToVsn
 rename_tmp_service(EVsn,TmpVsn,NewVsn) ->
-    FromName = hd(string:tokens(atom_to_list(node()),"@")) ++ "_" ++ TmpVsn,
-    ToName = hd(string:tokens(atom_to_list(node()),"@")) ++ "_" ++ NewVsn,
+    FromName = hd(string:lexemes(atom_to_list(node()),"@")) ++ "_" ++ TmpVsn,
+    ToName = hd(string:lexemes(atom_to_list(node()),"@")) ++ "_" ++ NewVsn,
     case erlsrv:get_service(EVsn,ToName) of
 	{error, _Error} ->
 	    ok;
@@ -1207,9 +1207,9 @@ rename_service(EVsn,FromName,ToName) ->
 %%% in which case we try to rename the old service to the new name and try
 %%% to update heart's view of what service we are really running.
 do_make_services_permanent(PermanentVsn,Vsn, PermanentEVsn, EVsn) ->
-    PermName = hd(string:tokens(atom_to_list(node()),"@")) 
+    PermName = hd(string:lexemes(atom_to_list(node()),"@"))
 	++ "_" ++ PermanentVsn,
-    Name = hd(string:tokens(atom_to_list(node()),"@")) 
+    Name = hd(string:lexemes(atom_to_list(node()),"@"))
 	++ "_" ++ Vsn,
     case erlsrv:get_service(EVsn,Name) of
 	{error, _Error} ->
@@ -1296,7 +1296,7 @@ do_make_permanent(#state{releases = Releases,
 
 
 do_back_service(OldVersion, CurrentVersion,OldEVsn,CurrentEVsn) ->
-    NN = hd(string:tokens(atom_to_list(node()),"@")),
+    NN = hd(string:lexemes(atom_to_list(node()),"@")),
     OldName = NN ++ "_" ++ OldVersion,
     CurrentName = NN ++ "_" ++ CurrentVersion,
     UpdData = case erlsrv:get_service(CurrentEVsn,CurrentName) of
@@ -1385,7 +1385,7 @@ do_remove_service(Vsn) ->
     %% Very unconditionally remove the service.
     %% Note that the service could already have been removed when
     %% making another release permanent.
-    ServiceName = hd(string:tokens(atom_to_list(node()),"@")) 
+    ServiceName = hd(string:lexemes(atom_to_list(node()),"@"))
 	++ "_" ++ Vsn,
     case erlsrv:get_service(ServiceName) of
 	{error, _Error} ->
@@ -1670,9 +1670,9 @@ flush() ->
 prepare_restart_nt(#release{erts_vsn = EVsn, vsn = Vsn},
 		   #release{erts_vsn = PermEVsn, vsn = PermVsn},
 		   DataFileName) ->
-    CurrentServiceName = hd(string:tokens(atom_to_list(node()),"@")) 
+    CurrentServiceName = hd(string:lexemes(atom_to_list(node()),"@"))
 	++ "_" ++ PermVsn,
-    FutureServiceName = hd(string:tokens(atom_to_list(node()),"@")) 
+    FutureServiceName = hd(string:lexemes(atom_to_list(node()),"@"))
 	++ "_" ++ Vsn,
     CurrentService = case erlsrv:get_service(PermEVsn,CurrentServiceName) of
 			 {error, _} = Error1 ->
diff --git a/lib/sasl/src/sasl.app.src b/lib/sasl/src/sasl.app.src
index b7bb9133ff..1e8e58a978 100644
--- a/lib/sasl/src/sasl.app.src
+++ b/lib/sasl/src/sasl.app.src
@@ -32,8 +32,6 @@
 	       sasl_report, 
 	       sasl_report_tty_h, 
 	       sasl_report_file_h, 
-	       si,
-	       si_sasl_supp,
 	       systools, 
 	       systools_make, 
 	       systools_rc, 
diff --git a/lib/sasl/src/sasl.appup.src b/lib/sasl/src/sasl.appup.src
index dcb568c413..94af164b20 100644
--- a/lib/sasl/src/sasl.appup.src
+++ b/lib/sasl/src/sasl.appup.src
@@ -18,11 +18,7 @@
 %% %CopyrightEnd%
 {"%VSN%",
  %% Up from - max one major revision back
- [{<<"3\\.0((\\.[0-3])(\\.[0-9]+)*)?">>,[restart_new_emulator]}, % OTP-19.*
-  {<<"3\\.0\\.[4-9](\\.[0-9]+)*">>,[restart_new_emulator]},      % OTP-20.0*
-  {<<"3\\.1(\\.[0-9]+)*">>,[restart_new_emulator]}],             % OTP-20.1*
+ [{<<"3\\.0\\.4(\\.[0-9]+)*">>,[restart_new_emulator]}], % OTP-20.*
  %% Down to - max one major revision back
- [{<<"3\\.0((\\.[0-3])(\\.[0-9]+)*)?">>,[restart_new_emulator]}, % OTP-19.*
-  {<<"3\\.0\\.[4-9](\\.[0-9]+)*">>,[restart_new_emulator]},       % OTP-20.0*
-  {<<"3\\.1(\\.[0-9]+)*">>,[restart_new_emulator]}]              % OTP-20.1*
+ [{<<"3\\.0\\.4(\\.[0-9]+)*">>,[restart_new_emulator]}]  % OTP-20.*
 }.
diff --git a/lib/sasl/src/si.erl b/lib/sasl/src/si.erl
deleted file mode 100644
index 275c6d508b..0000000000
--- a/lib/sasl/src/si.erl
+++ /dev/null
@@ -1,169 +0,0 @@
-%%
-%% %CopyrightBegin%
-%% 
-%% Copyright Ericsson AB 1996-2016. All Rights Reserved.
-%% 
-%% Licensed under the Apache License, Version 2.0 (the "License");
-%% you may not use this file except in compliance with the License.
-%% You may obtain a copy of the License at
-%%
-%%     http://www.apache.org/licenses/LICENSE-2.0
-%%
-%% Unless required by applicable law or agreed to in writing, software
-%% distributed under the License is distributed on an "AS IS" BASIS,
-%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-%% See the License for the specific language governing permissions and
-%% limitations under the License.
-%% 
-%% %CopyrightEnd%
-%%
-%%-----------------------------------------------------------------
-%% l(format_lib_supp), l(si_sasl_supp), l(si), l(si_ms_aos_supp), l(misc_supp).
-%% c(format_lib_supp), c(si_sasl_supp), c(si), c(si_ms_aos_supp), c(misc_supp).
-%%-----------------------------------------------------------------
-
-
-%%--------------------------------------------------
-%% Description:
-%% Status Inspection, main module.
-%%--------------------------------------------------
-
--module(si).
-
-
-%% External exports
--export([h/0, help/0, start/0, start/1, start_log/1, stop_log/0,
-	 abbrevs/0, pi/1, pi/2, pi/3, pi/4, ppi/1, ppi/3, stop/0]).
-
-%% Internal exports
--export([pi_impl/2, test/0]).
-
-
-%%--------------------------------------------------
-%% Table of contents
-%% 1. Interface
-%% 2. Implementation
-
-
--import(si_sasl_supp, [status_info/1, make_pid/1, p/1]).
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%% 1. Interface
-%%--------------------------------------------------
-
-h() -> print_help().
-help() -> print_help().
-
-start() -> si_sasl_supp:start().
-start(Options) -> si_sasl_supp:start(Options).
-
-stop() -> si_sasl_supp:stop().
-
-start_log(FileName) ->
-    si_sasl_supp:start_log(FileName).
-
-stop_log() ->
-    si_sasl_supp:stop_log().
-
-%%%-----------------------------------------------------------------
-%%% All functions can be called with an option 'normal' or 'all';
-%%% default is 'normal'.
-%%%-----------------------------------------------------------------
-
-abbrevs() ->
-    io:format("~p", [lists:append(si_sasl_supp:process_abbrevs(),
-				  process_abbrevs())]).
-
-%%-----------------------------------------------------------------
-%% Process Info that tries to determine processtype (=Module), then
-%% it uses this Module:format_info to format data from status_info/1.
-%%-----------------------------------------------------------------
-pi(XPid) -> 
-    si_sasl_supp:si_exec({si, pi_impl}, [normal, XPid]).
-
-pi(Opt, XPid) ->
-    si_sasl_supp:si_exec({si, pi_impl}, [si_sasl_supp:valid_opt(Opt), XPid]).
-
-pi(A, B, C) when is_integer(A), is_integer(B), is_integer(C) ->
-    si_sasl_supp:si_exec({si, pi_impl}, [normal, {A, B, C}]).
-
-pi(Opt, A, B, C) when is_integer(A), is_integer(B), is_integer(C) ->
-    si_sasl_supp:si_exec({si, pi_impl}, [si_sasl_supp:valid_opt(Opt), {A, B, C}]).
-
-%%-----------------------------------------------------------------
-%% Pretty print Process_Info.
-%%-----------------------------------------------------------------
-ppi(XPid) ->
-    si_sasl_supp:ppi(XPid).
-ppi(A, B, C) ->
-    si_sasl_supp:ppi(A, B, C).
-
-
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%% 2. Implementation
-%%--------------------------------------------------
-
-print_help() ->
-    p("~nStatus Inspection tool - usage"),
-    p("=============================="),
-    p("    For all these functions, Opt is an optional argument"),
-    p("    which can be 'normal' or 'all'; default is 'normal'."),
-    p("    If 'all', all information will be printed."),
-    p("    A Pid can be: \"<A.B.C>\", {A, B, C}, B, a registered_name or an abbrev."),
-    p("ANY PROCESS"),
-    p("si:pi([Opt,] Pid)   - Formatted information about any process that"),
-    p("                      SI recognises."),
-    p("si:pi([Opt,] A,B,C) - Same as si:pi({A, B, C})."), 
-    p("si:ppi(Pid)         - Pretty formating of process_info."),
-    p("                      Works for any process."),
-    p("MISC"),
-    p("si:abbrevs()        - Lists valid abbreviations."),
-    p("si:start_log(Filename) - Logging to file."),
-    p("si:stop_log()"),
-    p("si:start()          - Starts Status Inspection (the si_server)."),
-    p("si:start([{start_log, FileName}])"),
-    p("si:stop()           - Shut down SI.").
-
-
-%%--------------------------------------------------
-%% Copied (and modified) code from si_sasl_supp.  
-%%--------------------------------------------------
-pi_impl(Opt, XPid) ->
-    case make_pid(try_local_expand_abbrev(XPid)) of
-	Pid when is_pid(Pid) ->
-	    case status_info(Pid) of
-		{status_info, Pid, {module, Module}, Data} ->
-		    si_sasl_supp:do_best_printout(Opt, Pid, Module, Data);
-		{error, Reason} ->
-		    _ = si_sasl_supp:ppi_impl(Pid),
-		    {error, {"can not get status info from process:",
-			     XPid,
-			     Reason}};
-		Else ->
-		    {error, {"unknown status info", Else}}
-	    end;
-	{error, Reason} ->
-	    {error, Reason}
-    end.
-
-%%--------------------------------------------------
-%% Functions for handling of abbreviations
-%%--------------------------------------------------
-try_local_expand_abbrev(Abbrev) ->
-    case si_sasl_supp:expand_abbrev(Abbrev, process_abbrevs()) of
-	{value, {_, RealName}} -> RealName;
-	_ -> Abbrev
-    end.
-
-process_abbrevs() ->
-    [].
-
-%% Test get_status_info/format_status_info for all implemented servers.
-test() ->
-    lists:foreach(fun test_all_registered/1,
-		  lists:append(si_sasl_supp:process_abbrevs(),
-			       process_abbrevs())).
-
-test_all_registered({Al, _Ful}) ->
-    si:pi(all, Al).
diff --git a/lib/sasl/src/si_sasl_supp.erl b/lib/sasl/src/si_sasl_supp.erl
deleted file mode 100644
index cce628f8c4..0000000000
--- a/lib/sasl/src/si_sasl_supp.erl
+++ /dev/null
@@ -1,380 +0,0 @@
-%%
-%% %CopyrightBegin%
-%%
-%% Copyright Ericsson AB 1996-2016. All Rights Reserved.
-%%
-%% Licensed under the Apache License, Version 2.0 (the "License");
-%% you may not use this file except in compliance with the License.
-%% You may obtain a copy of the License at
-%%
-%%     http://www.apache.org/licenses/LICENSE-2.0
-%%
-%% Unless required by applicable law or agreed to in writing, software
-%% distributed under the License is distributed on an "AS IS" BASIS,
-%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-%% See the License for the specific language governing permissions and
-%% limitations under the License.
-%%
-%% %CopyrightEnd%
-%%
--module(si_sasl_supp).
-
--behaviour(gen_server).
-
-%%%---------------------------------------------------------------------------
-%%% Description:
-%%% This module contains the BOS specific parts of the Status Inspection Tool.
-%%%---------------------------------------------------------------------------
-
-
-%% user interface
--export([h/0, help/0, start_log/1, stop_log/0, abbrevs/0, pi/1, pi/2, pi/3,
-	 pi/4, ppi/1, ppi/3, start/0, start/1, stop/0, start_link/1]).
-
-%% intermodule exports
--export([make_pid/1, make_pid/3, process_abbrevs/0, expand_abbrev/2,
-	 status_info/1, valid_opt/1, p/1, do_best_printout/4,
-	 si_exec/2, handle_call/3, terminate/2]).
-
-%% exports for use within module
--export([init/1, start_log_impl/1, pi_impl/2, ppi_impl/1]).
-
-%% other gen_server callbacks (not used)
--export([handle_cast/2, handle_info/2, code_change/3]).
-
-%%--------------------------------------------------
-%% Table of contents
-%% 1. Interface
-%% 2. SI - Server
-%% 3. Code
-%% 4. Selectors
-%%--------------------------------------------------
-
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%% 1. Interface
-%% -----------------------------------------------------
-
-h() -> print_help().
-help() -> print_help().
-
-si_exec(Fun, Args) -> call({si_exec, Fun, Args}).
-
-start_log(FileName) ->
-    call({start_log, FileName}).
-
-stop_log() ->
-    call(stop_log).
-
-abbrevs() ->
-    io:format("~p", [process_abbrevs()]).
-
-%%-----------------------------------------------------------------
-%% All functions can be called with an option 'normal' or 'all';
-%% default is 'normal'.
-%%-----------------------------------------------------------------
-%% Process Info that tries to determine processtype (=Module), then
-%% it uses this Module:format_info to format data from status_info/1.
-%%-----------------------------------------------------------------
-pi(XPid) -> 
-    si_exec({si_sasl_supp, pi_impl}, [normal, XPid]).
-
-pi(Opt, XPid) ->
-    si_exec({si_sasl_supp, pi_impl}, [valid_opt(Opt), XPid]).
-
-pi(A, B, C) when is_integer(A), is_integer(B), is_integer(C) ->
-    si_exec({si_sasl_supp, pi_impl}, [normal, {A, B, C}]).
-
-pi(Opt, A, B, C) when is_integer(A), is_integer(B), is_integer(C) ->
-    si_exec({si_sasl_supp, pi_impl}, [valid_opt(Opt), {A, B, C}]).
-
-%%-----------------------------------------------------------------
-%% Pretty print Process_Info.
-%%-----------------------------------------------------------------
-ppi(XPid) ->
-    case whereis(si_server) of
-	undefined ->           % You can always run ppi.
-	    ppi_impl(XPid);    % if si_server is down, use standard_io
-	_ ->
-	    si_exec({si_sasl_supp, ppi_impl}, [XPid])
-    end.
-ppi(A, B, C) ->
-    case whereis(si_server) of
-	undefined ->               % You can always run ppi.
-	    ppi_impl({A, B, C});   % if si_server is down, use standard_io
-	_ ->
-	    si_exec({si_sasl_supp, ppi_impl}, [{A, B, C}])
-    end.
-
-
-
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%% 2. SI - Server
-%%--------------------------------------------------
--record(state, {}).
-
-start() -> start([]).
-start(Options) ->
-    supervisor:start_child(sasl_sup, 
-			   {si_server, {si_sasl_supp, start_link, [Options]},
-			    temporary, brutal_kill, worker, [si_sasl_supp]}).
-
-start_link(_Options) ->
-    gen_server:start_link({local, si_server}, si_sasl_supp, [], []).
-
-stop() ->
-    call(stop),
-    supervisor:delete_child(sasl_sup, si_server).
-
-
-init(Options) ->
-    process_flag(trap_exit, true),
-    start_log_impl(get_option(Options, start_log, standard_io)),
-    {ok, #state{}}.
-
-%%-----------------------------------------------------------------
-%% If an error occurs and we're logging to file: write the error
-%% to the file.
-%% Always return the error.
-%% The only data held by the si_server is the device in its process dictionary.
-%%-----------------------------------------------------------------
-handle_call({si_exec, Fun, Args}, _From, State) ->
-    case catch apply(Fun, Args) of
-	{'EXIT', Reason} ->
-	    print_error(get(device),
-			"SI internal error. Reason: ~w~n",
-			[Reason]),
-	    {stop, shutdown, {internal_error, Reason}, State};
-	{error, Reason} ->
-	    print_error(get(device), "~nSI error: ~w~n", [Reason]),
-	    {reply, {error, Reason}, State};
-	X -> 
-	    {reply, X, State}
-    end;
-handle_call({start_log, FileName}, _From, State) ->
-    start_log_impl(FileName),
-    {reply, ok, State};
-handle_call(stop_log, _From, State) ->
-    start_log_impl(standard_io),
-    {reply, ok, State};
-handle_call(stop, _From, State) ->
-    start_log_impl(standard_io),
-    {stop, normal, stopped, State}.
-
-terminate(_Reason, _State) ->
-    _ = close_device(get(device)),
-    ok.
-
-handle_cast(_Msg, State) ->
-    {noreply, State}.
-handle_info(_Info, State) ->
-    {noreply, State}.
-code_change(_OldVsn, State, _Extra) ->
-    {ok, State}.
-
-close_device(standard_io) -> ok;
-close_device(Fd) -> file:close(Fd).
-
-print_error(standard_io, _, _) -> ok;
-print_error(Device, Format, Args) ->
-    io:format(Device, Format, Args).
-
-get_option(Options, Key, Default) ->
-    case lists:keysearch(Key, 1, Options) of
-	{value, {_Key, Value}} -> Value;
-	_ -> Default
-    end.
-
-open_log_file(undefined, NewFile) ->
-    open_log_file(NewFile);
-open_log_file(standard_io, NewFile) ->
-    open_log_file(NewFile);
-open_log_file(OldFile, NewFile) ->
-    _ = file:close(OldFile),
-    open_log_file(NewFile).
-
-open_log_file(standard_io) -> standard_io;
-open_log_file(FileName) ->
-    case file:open(FileName, [write]) of
-	{ok, Fd} -> Fd;
-	Error -> 
-	    io:format("si_sasl_supp: Cannot open file '~s' (~w).~n",
-		      [FileName, Error]),
-	    io:format("si_sasl_supp: Using standard_io~n"),
-	    standard_io
-    end.
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%% 3. Code
-%%--------------------------------------------------
-
-%%-----------------------------------------------------------------
-%% call(Request) -> Term
-%%-----------------------------------------------------------------
-call(Req) ->
-    gen_server:call(si_server, Req, infinity).
-
-%%--------------------------------------------------
-%% Makes a Pid of almost anything.
-%% Returns: Pid|{error, Reason}
-%% Fails: Never.
-%%--------------------------------------------------
-make_pid(A,B,C) when is_integer(A), is_integer(B), is_integer(C) ->
-    list_to_pid(lists:concat(["<",A,".",B,".",C,">"])).
-make_pid(P) when is_pid(P) -> P;
-make_pid(undefined) -> undefined;
-make_pid(P) when is_atom(P) ->
-    case whereis(P) of
-	undefined ->
-	    case expand_abbrev(P, process_abbrevs()) of
-		{error, Reason} -> {error, Reason};
-		{value, {_Abbrev, FullName}} ->
-		    case whereis(FullName) of
-			undefined ->
-			    {error, {'process not registered', P}};
-			Pid -> Pid
-		    end
-	    end;
-	Pid -> Pid
-    end;
-make_pid(P) when is_list(P) -> list_to_pid(P);
-make_pid({A, B, C}) -> make_pid(A, B, C);
-make_pid(X) -> {error, {'can not make a pid of', X}}.
-
-process_abbrevs() ->
-    [{init, init},
-     {fs, file_server}].
-     
-%%--------------------------------------------------
-%% Args: Abbrevs is an assoc-list of {Abbrev, RealName}
-%% Returns: {value, {Abbrev, FullName}}|{error, Reason}
-%%--------------------------------------------------
-expand_abbrev(ProcessName, Abbrevs) ->
-    case lists:keysearch(ProcessName, 1, Abbrevs) of
-	{value, {Abbrev, FullName}} ->
-	    {value, {Abbrev, FullName}};
-	_ ->
-	    case lists:keysearch(ProcessName, 2, Abbrevs) of
-		{value, {Abbrev, FullName}} ->
-		    {value, {Abbrev, FullName}};
-		_ ->
-		    {error, {'invalid process name', ProcessName}}
-	    end
-    end.
-
-%%-----------------------------------------------------------------
-%% This is the function that actually gets the information out
-%% of the agent/server/...
-%% Returns: {status_info, Pid, Type, Data}
-%%        | {error, Reason}
-%%-----------------------------------------------------------------
-status_info(Pid) when is_pid(Pid) ->
-    case catch sys:get_status(Pid, 5000) of
-	{status, Pid, Type, Info} ->
-	    {status_info, Pid, Type, Info};
-	_ ->
-	    {error, {'process does not respond', Pid}}
-    end;
-
-status_info(X) ->
-    {error, {'not a pid', X}}.
-
-%%--------------------------------------------------
-%% Implementation starts here.
-%%--------------------------------------------------
-start_log_impl(FileName) ->
-    put(device, open_log_file(get(device), FileName)).
-
-valid_opt(all) -> all;
-valid_opt(_Opt) -> normal.
-
-
-print_help() ->
-    p("- - - - - - - - PROCESSES - - - - - - - - - "),
-    p("si_sasl_supp:pi([Opt,] Pid)   - Formatted information about any process that"),
-    p("                      SI recognises."),
-    p("si_sasl_supp:pi([Opt,] A,B,C) - Same as si_sasl_supp:pi({A, B, C})."), 
-    p("si_sasl_supp:ppi(Pid)         - Pretty formating of process_info."),
-    p("                      Works for any process."),
-    p("- - - - - - - - MISC  - - - - - - - - - - - "),
-    p("si_sasl_supp:abbrevs()        - Lists valid abbreviations."),
-    p("si_sasl_supp:start_log(FileNname)"),
-    p("si_sasl_supp:stop_log()"),
-    p("si_sasl_supp:start()          - Starts Status Inspection (the si_server)."),
-    p("si_sasl_supp:start([{start_log, FileName}])"),
-    p("si_sasl_supp:stop()           - Shut down SI.").
-
-
-
-%% Convenient shorthand
-p(X) ->
-    io:format(lists:append(X, "~n")).
-
-pi_impl(Opt, XPid) ->
-    case make_pid(XPid) of
-	Pid when is_pid(Pid) ->
-	    case status_info(Pid) of
-		{status_info, Pid, {module, Module}, Data} ->
-		    do_best_printout(Opt, Pid, Module, Data);
-		{error, Reason} ->
-		    _ = ppi_impl(Pid),
-		    {error, {"can not get status info from process:",
-			     XPid,
-			     Reason}}
-	    end;
-	{error, Reason} ->
-	    {error, Reason}
-    end.
-
-%%--------------------------------------------------
-%% Is there a format_info for this process? In that case, run it!
-%% Return ok|{error, Reason}
-%% Fails: Never.
-%%--------------------------------------------------
-do_best_printout(Opt, Pid, Mod, Data) when is_pid(Pid) ->
-    case print_info(get(device), Pid, {Mod, format_status}, Opt, Data) of
-	ok -> ok;
-	{error, Reason} ->
-	    _ = ppi_impl(Pid),
-	    {error, Reason}
-    end.
-
-ppi_impl(XPid) -> 
-    case make_pid(XPid) of
-	P when is_pid(P) -> 
-	    case process_info(P) of
-		undefined ->
-		    {error, {'dead process', P}};
-		PI ->
-		    Device = case get(device) of
-				 undefined -> standard_io;
-				 X -> X
-			     end,
-		    io:format(Device, "~nPretty Process Info~n", []),
-		    io:format(Device, "-------------------~n", []),
-		    io:format(Device, "~p~n", [PI])
-	    end;
-	_ -> {error, {no_pid, XPid}}
-    end.
-
-print_info(Device, Pid, {Module, Func}, Opt, Data) ->
-    case erlang:function_exported(Module, Func, 2) of
-	true ->
-	    case catch apply(Module, Func, [Opt, Data]) of
-		Format when is_list(Format) ->
-		    format_lib_supp:print_info(Device, 79,
-					       add_pid_to_format(Pid, Format)),
-		    ok;
-		Other -> {error, {'invalid format', Other}}
-	    end;
-	_ ->
-	    {error, {no_such_function, Module, Func}}
-    end.
-
-add_pid_to_format(Pid, [{header, H} | T]) ->
-    [{header, H}, {data, [{"Pid", Pid}]} | T];
-add_pid_to_format(Pid, List) ->
-    [{data, [{"Pid", Pid}]} | List].
-
-
diff --git a/lib/sasl/src/systools_make.erl b/lib/sasl/src/systools_make.erl
index 391b1fb5cc..9d960b7361 100644
--- a/lib/sasl/src/systools_make.erl
+++ b/lib/sasl/src/systools_make.erl
@@ -1501,7 +1501,7 @@ preloaded() ->
     [erl_prim_loader,erl_tracer,erlang,
      erts_code_purger,erts_dirty_process_code_checker,
      erts_internal,erts_literal_area_collector,
-     init,otp_ring0,prim_eval,prim_file,
+     init,otp_ring0,prim_buffer,prim_eval,prim_file,
      prim_inet,prim_zip,zlib].
 
 %%______________________________________________________________________
diff --git a/lib/sasl/test/release_handler_SUITE.erl b/lib/sasl/test/release_handler_SUITE.erl
index 50932e89e4..824820c214 100644
--- a/lib/sasl/test/release_handler_SUITE.erl
+++ b/lib/sasl/test/release_handler_SUITE.erl
@@ -22,7 +22,8 @@
 -include_lib("common_test/include/ct.hrl").
 -include("test_lib.hrl").
 
--compile(export_all).
+-compile([export_all, nowarn_export_all]).
+-export([scheduler_wall_time/0, garbage_collect/0]). %% rpc'ed
 
 % Default timetrap timeout (set in init_per_testcase).
 %-define(default_timeout, ?t:minutes(40)).
@@ -1085,8 +1086,9 @@ otp_9395_update_many_mods(Conf) when is_list(Conf) ->
     Rel2Dir = filename:dirname(Rel2),
 
     %% Start a slave node
+    PA = filename:dirname(code:which(?MODULE)),
     {ok, Node} = t_start_node(otp_9395_update_many_mods, Rel1,
-			      filename:join(Rel1Dir,"sys.config")),
+			      filename:join(Rel1Dir,"sys.config"), "-pa " ++ PA),
 
     %% Start a lot of processes on the new node, all with refs to each
     %% module that will be updated
@@ -1109,8 +1111,8 @@ otp_9395_update_many_mods(Conf) when is_list(Conf) ->
 		  [RelVsn2, filename:join(Rel2Dir, "sys.config")]),
 
     %% First, install release directly and check how much time it takes
-    rpc:call(Node,erlang,garbage_collect,[]),
-    rpc:call(Node,erlang,system_flag,[scheduler_wall_time,true]),
+    rpc:call(Node,?MODULE,garbage_collect,[]),
+    SWTFlag0 = spawn_link(Node, ?MODULE, scheduler_wall_time, []),
     {TInst0,{ok, _, []}} =
 	timer:tc(rpc,call,[Node, release_handler, install_release, [RelVsn2]]),
     SWT0 = rpc:call(Node,erlang,statistics,[scheduler_wall_time]),
@@ -1135,9 +1137,9 @@ otp_9395_update_many_mods(Conf) when is_list(Conf) ->
 
     %% Finally install release after check and purge, and check that
     %% this install was faster than the first.
-    rpc:call(Node,erlang,system_flag,[scheduler_wall_time,false]),
-    rpc:call(Node,erlang,garbage_collect,[]),
-    rpc:call(Node,erlang,system_flag,[scheduler_wall_time,true]),
+    SWTFlag0 ! die,
+    rpc:call(Node,?MODULE,garbage_collect,[]),
+    _SWTFlag1 = spawn_link(Node, ?MODULE, scheduler_wall_time, []),
     {TInst2,{ok, _RelVsn1, []}} =
 	timer:tc(rpc,call,[Node, release_handler, install_release, [RelVsn2]]),
     SWT2 = rpc:call(Node,erlang,statistics,[scheduler_wall_time]),
@@ -1161,6 +1163,15 @@ otp_9395_update_many_mods(Conf) when is_list(Conf) ->
 
     ok.
 
+scheduler_wall_time() ->
+    erlang:system_flag(scheduler_wall_time,true),
+    receive _Msg -> normal end.
+
+garbage_collect() ->
+    Pids = processes(),
+    [erlang:garbage_collect(Pid) || Pid <- Pids].
+
+
 otp_9395_update_many_mods(cleanup,_Conf) ->
     stop_node(node_name(otp_9395_update_many_mods)).
 
@@ -1190,8 +1201,9 @@ otp_9395_rm_many_mods(Conf) when is_list(Conf) ->
     Rel2Dir = filename:dirname(Rel2),
 
     %% Start a slave node
+    PA = filename:dirname(code:which(?MODULE)),
     {ok, Node} = t_start_node(otp_9395_rm_many_mods, Rel1,
-			      filename:join(Rel1Dir,"sys.config")),
+			      filename:join(Rel1Dir,"sys.config"), "-pa " ++ PA),
 
     %% Start a lot of processes on the new node, all with refs to each
     %% module that will be updated
@@ -1214,8 +1226,8 @@ otp_9395_rm_many_mods(Conf) when is_list(Conf) ->
 		  [RelVsn2, filename:join(Rel2Dir, "sys.config")]),
 
     %% First, install release directly and check how much time it takes
-    rpc:call(Node,erlang,garbage_collect,[]),
-    rpc:call(Node,erlang,system_flag,[scheduler_wall_time,true]),
+    rpc:call(Node,?MODULE,garbage_collect,[]),
+    SWTFlag0 = spawn_link(Node, ?MODULE, scheduler_wall_time, []),
     {TInst0,{ok, _, []}} =
 	timer:tc(rpc,call,[Node, release_handler, install_release, [RelVsn2]]),
     SWT0 = rpc:call(Node,erlang,statistics,[scheduler_wall_time]),
@@ -1240,9 +1252,9 @@ otp_9395_rm_many_mods(Conf) when is_list(Conf) ->
 
     %% Finally install release after check and purge, and check that
     %% this install was faster than the first.
-    rpc:call(Node,erlang,system_flag,[scheduler_wall_time,false]),
-    rpc:call(Node,erlang,garbage_collect,[]),
-    rpc:call(Node,erlang,system_flag,[scheduler_wall_time,true]),
+    SWTFlag0 ! die,
+    rpc:call(Node,?MODULE,garbage_collect,[]),
+    _SWTFlag1 = spawn_link(Node, ?MODULE, scheduler_wall_time, []),
     {TInst2,{ok, _RelVsn1, []}} =
 	timer:tc(rpc,call,[Node, release_handler, install_release, [RelVsn2]]),
     SWT2 = rpc:call(Node,erlang,statistics,[scheduler_wall_time]),
@@ -1384,9 +1396,9 @@ upgrade_supervisor(Conf) when is_list(Conf) ->
     %% Check that the restart strategy and child spec is updated
     {status, _, {module, _}, [_, _, _, _, [_,_,{data,[{"State",State}]}|_]]} =
 	rpc:call(Node,sys,get_status,[a_sup]),
-    {state,_,RestartStrategy,[Child],_,_,_,_,_,_,_} = State,
+    {state,_,RestartStrategy,{[a],Db},_,_,_,_,_,_,_} = State,
     one_for_all = RestartStrategy, % changed from one_for_one
-    {child,_,_,_,_,brutal_kill,_,_} = Child, % changed from timeout 2000
+    {child,_,_,_,_,brutal_kill,_,_} = maps:get(a,Db), % changed from timeout 2000
 
     ok.
 
@@ -1835,24 +1847,32 @@ otp_10463_upgrade_script_regexp(cleanup,Config) ->
     code:del_path(filename:join([DataDir,regexp_appup,app1,ebin])),
     ok.
 
-no_dot_erlang(Conf) ->
-    PrivDir = ?config(data_dir,Conf),
-    {ok, OrigWd} = file:get_cwd(),
-    try
-	ok = file:set_cwd(PrivDir),
-
-	{ok, Wd} = file:get_cwd(),
-	io:format("Dir ~ts~n", [Wd]),
+no_dot_erlang(_Conf) ->
+    case init:get_argument(home) of
+        {ok,[[Home]]} when is_list(Home) ->
+            no_dot_erlang_1(Home);
+        _ -> ok
+    end.
 
+no_dot_erlang_1(Home) ->
+    DotErlang = filename:join(Home, ".erlang"),
+    BupErlang = filename:join(Home, ".erlang_testbup"),
+    try
+        {ok, Wd} = file:get_cwd(),
+        case filelib:is_file(DotErlang) of
+            true -> {ok, _} = file:copy(DotErlang, BupErlang);
+            false -> ok
+        end,
 	Erl0 =  filename:join([code:root_dir(),"bin","erl"]),
 	Erl = filename:nativename(Erl0),
 	Quote = "\"",
 	Args = " -noinput -run c pwd -run erlang halt",
-	ok = file:write_file(".erlang", <<"io:put_chars(\"DOT_ERLANG_READ\\n\").\n">>),
+	ok = file:write_file(DotErlang, <<"io:put_chars(\"DOT_ERLANG_READ\\n\").\n">>),
 
 	CMD1 = Quote ++ Erl ++ Quote ++ Args ,
 	case os:cmd(CMD1) of
-	    "DOT_ERLANG_READ" ++ _ -> ok;
+	    "DOT_ERLANG_READ" ++ _ ->
+                io:format("~p: Success~n", [?LINE]);
 	    Other1 ->
 		io:format("Failed: ~ts~n",[CMD1]),
 		io:format("Expected: ~s ++ _~n",["DOT_ERLANG_READ "]),
@@ -1862,7 +1882,7 @@ no_dot_erlang(Conf) ->
 	NO_DOT_ERL = " -boot no_dot_erlang",
 	CMD2 = Quote ++ Erl ++ Quote ++ NO_DOT_ERL ++ Args,
 	case lists:prefix(Wd, Other2 = os:cmd(CMD2)) of
-	    true -> ok;
+	    true -> io:format("~p: Success~n", [?LINE]);
 	    false ->
 		io:format("Failed: ~ts~n",[CMD2]),
 		io:format("Expected: ~s~n",["TESTOK"]),
@@ -1870,9 +1890,13 @@ no_dot_erlang(Conf) ->
 		exit({failed_to_start, no_dot_erlang})
 	end
     after
-	_ = file:delete(".erlang"),
-	ok = file:set_cwd(OrigWd),
-	ok
+        case filelib:is_file(BupErlang) of
+            true ->
+                {ok, _} = file:copy(BupErlang, DotErlang),
+                _ = file:delete(BupErlang);
+            false ->
+                _ = file:delete(DotErlang)
+        end
     end.
 
 %%%-----------------------------------------------------------------
diff --git a/lib/sasl/test/test_lib.hrl b/lib/sasl/test/test_lib.hrl
index 9a54937f96..f5210d4f27 100644
--- a/lib/sasl/test/test_lib.hrl
+++ b/lib/sasl/test/test_lib.hrl
@@ -1,3 +1,3 @@
 -define(ertsvsn,"4.4").
--define(kernelvsn,"5.0").
--define(stdlibvsn,"3.0").
+-define(kernelvsn,"5.3").
+-define(stdlibvsn,"3.4").
diff --git a/lib/ssl/src/Makefile b/lib/ssl/src/Makefile
index 2e7df9792e..8eba5cf347 100644
--- a/lib/ssl/src/Makefile
+++ b/lib/ssl/src/Makefile
@@ -1,7 +1,7 @@
 #
 # %CopyrightBegin%
 #
-# Copyright Ericsson AB 1999-2016. All Rights Reserved.
+# Copyright Ericsson AB 1999-2017. All Rights Reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -87,8 +87,7 @@ MODULES= \
 	ssl_v2 \
 	ssl_v3 \
 	tls_v1 \
-	dtls_v1 \
-	ssl_tls_dist_proxy
+	dtls_v1
 
 INTERNAL_HRL_FILES = \
 	ssl_alert.hrl ssl_cipher.hrl \
diff --git a/lib/ssl/src/dtls_connection.erl b/lib/ssl/src/dtls_connection.erl
index 073cb4009b..e5760e7951 100644
--- a/lib/ssl/src/dtls_connection.erl
+++ b/lib/ssl/src/dtls_connection.erl
@@ -467,7 +467,8 @@ init(Type, Event, State) ->
 error(enter, _, State) ->
     {keep_state, State};     
 error({call, From}, {start, _Timeout}, {Error, State}) ->
-    {stop_and_reply, normal, {reply, From, {error, Error}}, State};
+    ssl_connection:stop_and_reply(
+      normal, {reply, From, {error, Error}}, State);
 error({call, _} = Call, Msg, State) ->
     gen_handshake(?FUNCTION_NAME, Call, Msg, State);
 error(_, _, _) ->
@@ -821,7 +822,7 @@ handle_info({Protocol, _, _, _, Data}, StateName,
 	    next_event(StateName, Record, State);
 	#alert{} = Alert ->
 	    ssl_connection:handle_normal_shutdown(Alert, StateName, State0), 
-	    {stop, {shutdown, own_alert}}
+	    ssl_connection:stop({shutdown, own_alert}, State0)
     end;
 handle_info({CloseTag, Socket}, StateName,
 	    #state{socket = Socket, 
@@ -846,7 +847,7 @@ handle_info({CloseTag, Socket}, StateName,
                     ok
             end,
             ssl_connection:handle_normal_shutdown(?ALERT_REC(?FATAL, ?CLOSE_NOTIFY), StateName, State),
-            {stop, {shutdown, transport_closed}};
+            ssl_connection:stop({shutdown, transport_closed}, State);
         true ->
             %% Fixes non-delivery of final DTLS record in {active, once}.
             %% Basically allows the application the opportunity to set {active, once} again
@@ -872,7 +873,7 @@ handle_state_timeout(flight_retransmission_timeout, StateName,
 
 handle_alerts([], Result) ->
     Result;
-handle_alerts(_, {stop,_} = Stop) ->
+handle_alerts(_, {stop, _, _} = Stop) ->
     Stop;
 handle_alerts([Alert | Alerts], {next_state, StateName, State}) ->
      handle_alerts(Alerts, ssl_connection:handle_alert(Alert, StateName, State));
diff --git a/lib/ssl/src/dtls_udp_listener.erl b/lib/ssl/src/dtls_udp_listener.erl
index c789a32087..c9e04767aa 100644
--- a/lib/ssl/src/dtls_udp_listener.erl
+++ b/lib/ssl/src/dtls_udp_listener.erl
@@ -35,7 +35,7 @@
 
 -record(state, 
 	{port, 
-	 listner,
+	 listener,
 	 dtls_options,
 	 emulated_options,
 	 dtls_msq_queues = kv_new(),
@@ -81,7 +81,7 @@ init([Port, EmOpts, InetOptions, DTLSOptions]) ->
 		    first = true,
 		    dtls_options = DTLSOptions,
 		    emulated_options = EmOpts,
-		    listner = Socket,
+		    listener = Socket,
                     close = false}}
     catch _:_ ->
 	    {error, closed}
@@ -91,7 +91,7 @@ handle_call({accept, _}, _, #state{close = true} = State) ->
 
 handle_call({accept, Accepter}, From, #state{first = true,
 					     accepters = Accepters,
-					     listner = Socket} = State0) ->
+					     listener = Socket} = State0) ->
     next_datagram(Socket),
     State = State0#state{first = false,
 			 accepters = queue:in({Accepter, From}, Accepters)}, 		 
@@ -100,7 +100,7 @@ handle_call({accept, Accepter}, From, #state{first = true,
 handle_call({accept, Accepter}, From, #state{accepters = Accepters} = State0) ->
     State = State0#state{accepters = queue:in({Accepter, From}, Accepters)}, 		 
     {noreply, State};
-handle_call(sockname, _, #state{listner = Socket} = State) ->
+handle_call(sockname, _, #state{listener = Socket} = State) ->
     Reply = inet:sockname(Socket),
     {reply, Reply, State};
 handle_call(close, _, #state{dtls_processes = Processes,
@@ -114,7 +114,7 @@ handle_call(close, _, #state{dtls_processes = Processes,
                           end, queue:to_list(Accepters)),
             {reply, ok,  State#state{close = true, accepters = queue:new()}}
     end;
-handle_call({get_sock_opts, {SocketOptNames, EmOptNames}}, _, #state{listner = Socket,
+handle_call({get_sock_opts, {SocketOptNames, EmOptNames}}, _, #state{listener = Socket,
                                                                emulated_options = EmOpts} = State) ->
     case get_socket_opts(Socket, SocketOptNames) of
         {ok, Opts} ->
@@ -125,7 +125,7 @@ handle_call({get_sock_opts, {SocketOptNames, EmOptNames}}, _, #state{listner = S
 handle_call(get_all_opts, _, #state{dtls_options = DTLSOptions,
                                     emulated_options = EmOpts} = State) ->
     {reply, {ok, EmOpts, DTLSOptions}, State};
-handle_call({set_sock_opts, {SocketOpts, NewEmOpts}}, _, #state{listner = Socket, emulated_options = EmOpts0} = State) ->
+handle_call({set_sock_opts, {SocketOpts, NewEmOpts}}, _, #state{listener = Socket, emulated_options = EmOpts0} = State) ->
     set_socket_opts(Socket, SocketOpts),
     EmOpts = do_set_emulated_opts(NewEmOpts, EmOpts0),
     {reply, ok, State#state{emulated_options = EmOpts}}.
@@ -134,7 +134,7 @@ handle_cast({active_once, Client, Pid}, State0) ->
     State = handle_active_once(Client, Pid, State0),
     {noreply, State}.
 
-handle_info({udp, Socket, IP, InPortNo, _} = Msg, #state{listner = Socket} = State0) ->
+handle_info({udp, Socket, IP, InPortNo, _} = Msg, #state{listener = Socket} = State0) ->
     State = handle_datagram({IP, InPortNo}, Msg, State0),
     next_datagram(Socket),
     {noreply, State};
@@ -142,11 +142,11 @@ handle_info({udp, Socket, IP, InPortNo, _} = Msg, #state{listner = Socket} = Sta
 %% UDP socket does not have a connection and should not receive an econnreset
 %% This does however happens on on some windows versions. Just ignoring it
 %% appears to make things work as expected! 
-handle_info({udp_error, Socket, econnreset = Error}, #state{listner = Socket} = State) ->
+handle_info({udp_error, Socket, econnreset = Error}, #state{listener = Socket} = State) ->
     Report = io_lib:format("Ignore SSL UDP Listener: Socket error: ~p ~n", [Error]),
     error_logger:info_report(Report),
     {noreply, State};
-handle_info({udp_error, Socket, Error}, #state{listner = Socket} = State) ->
+handle_info({udp_error, Socket, Error}, #state{listener = Socket} = State) ->
     Report = io_lib:format("SSL UDP Listener shutdown: Socket error: ~p ~n", [Error]),
     error_logger:info_report(Report),
     {noreply, State#state{close=true}};
@@ -225,10 +225,10 @@ setup_new_connection(User, From, Client, Msg, #state{dtls_processes = Processes,
 						     dtls_msq_queues = MsgQueues,
 						     dtls_options = DTLSOpts,
 						     port = Port,
-						     listner = Socket,
+						     listener = Socket,
 						     emulated_options = EmOpts} = State) ->
     ConnArgs = [server, "localhost", Port, {self(), {Client, Socket}},
-		{DTLSOpts, EmOpts, udp_listner}, User, dtls_socket:default_cb_info()],
+		{DTLSOpts, EmOpts, udp_listener}, User, dtls_socket:default_cb_info()],
     case dtls_connection_sup:start_child(ConnArgs) of
 	{ok, Pid} ->
 	    erlang:monitor(process, Pid),
diff --git a/lib/ssl/src/inet6_tls_dist.erl b/lib/ssl/src/inet6_tls_dist.erl
index ffd7296f93..96ce4d493a 100644
--- a/lib/ssl/src/inet6_tls_dist.erl
+++ b/lib/ssl/src/inet6_tls_dist.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2015. All Rights Reserved.
+%% Copyright Ericsson AB 2015-2017. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -21,7 +21,8 @@
 %%
 -module(inet6_tls_dist).
 
--export([childspecs/0, listen/1, accept/1, accept_connection/5,
+-export([childspecs/0]).
+-export([listen/1, accept/1, accept_connection/5,
 	 setup/5, close/1, select/1]).
 
 childspecs() ->
@@ -43,4 +44,4 @@ setup(Node, Type, MyNode, LongOrShortNames,SetupTime) ->
     inet_tls_dist:gen_setup(inet6_tcp, Node, Type, MyNode, LongOrShortNames,SetupTime).
 
 close(Socket) ->
-    inet_tls_dist:close(Socket).
+    inet_tls_dist:gen_close(inet6_tcp, Socket).
diff --git a/lib/ssl/src/inet_tls_dist.erl b/lib/ssl/src/inet_tls_dist.erl
index 4c677b9c33..8e605bec65 100644
--- a/lib/ssl/src/inet_tls_dist.erl
+++ b/lib/ssl/src/inet_tls_dist.erl
@@ -21,17 +21,26 @@
 %%
 -module(inet_tls_dist).
 
--export([childspecs/0, listen/1, accept/1, accept_connection/5,
+-export([childspecs/0]).
+-export([listen/1, accept/1, accept_connection/5,
 	 setup/5, close/1, select/1, is_node_name/1]).
 
 %% Generalized dist API
 -export([gen_listen/2, gen_accept/2, gen_accept_connection/6,
-	 gen_setup/6, gen_select/2]).
+	 gen_setup/6, gen_close/2, gen_select/2]).
+
+-export([split_node/1, nodelay/0]).
+
+-export([dbg/0]). % Debug
 
 -include_lib("kernel/include/net_address.hrl").
 -include_lib("kernel/include/dist.hrl").
 -include_lib("kernel/include/dist_util.hrl").
 
+-include("ssl_api.hrl").
+
+%% -------------------------------------------------------------------------
+
 childspecs() ->
     {ok, [{ssl_dist_sup,{ssl_dist_sup, start_link, []},
 	   permanent, infinity, supervisor, [ssl_dist_sup]}]}.
@@ -40,127 +49,398 @@ select(Node) ->
     gen_select(inet_tcp, Node).
 
 gen_select(Driver, Node) ->
-    case split_node(atom_to_list(Node), $@, []) of
-	[_, Host] ->
-	    case inet:getaddr(Host, Driver:family()) of
+    case split_node(Node) of
+        false ->
+            false;
+        Host ->
+	    case Driver:getaddr(Host) of
 		{ok, _} -> true;
 		_ -> false
-	    end;
-	_ -> 
-	    false
+	    end
     end.
 
-is_node_name(Node) when is_atom(Node) ->
-    select(Node);
-is_node_name(_) ->
-    false.
+%% -------------------------------------------------------------------------
+
+is_node_name(Node) ->
+    case split_node(Node) of
+        false ->
+            false;
+        _Host ->
+            true
+    end.
+
+%% -------------------------------------------------------------------------
+
+hs_data_common(#sslsocket{pid = DistCtrl} = SslSocket) ->
+    #hs_data{
+       f_send =
+           fun (Ctrl, Packet) when Ctrl == DistCtrl ->
+                   f_send(SslSocket, Packet)
+           end,
+       f_recv =
+           fun (Ctrl, Length, Timeout) when Ctrl == DistCtrl ->
+                   f_recv(SslSocket, Length, Timeout)
+           end,
+       f_setopts_pre_nodeup =
+           fun (Ctrl) when Ctrl == DistCtrl ->
+                   f_setopts_pre_nodeup(SslSocket)
+           end,
+       f_setopts_post_nodeup =
+           fun (Ctrl) when Ctrl == DistCtrl ->
+%%%                   sys:trace(Ctrl, true),
+                   f_setopts_post_nodeup(SslSocket)
+           end,
+       f_getll =
+           fun (Ctrl) when Ctrl == DistCtrl ->
+                   f_getll(DistCtrl)
+           end,
+       f_address =
+           fun (Ctrl, Node) when Ctrl == DistCtrl ->
+                   f_address(SslSocket, Node)
+           end,
+       mf_tick =
+           fun (Ctrl) when Ctrl == DistCtrl ->
+                   mf_tick(DistCtrl)
+           end,
+       mf_getstat =
+           fun (Ctrl) when Ctrl == DistCtrl ->
+                   mf_getstat(SslSocket)
+           end,
+       mf_setopts =
+           fun (Ctrl, Opts) when Ctrl == DistCtrl ->
+                   mf_setopts(SslSocket, Opts)
+           end,
+       mf_getopts =
+           fun (Ctrl, Opts) when Ctrl == DistCtrl ->
+                   mf_getopts(SslSocket, Opts)
+           end,
+       f_handshake_complete =
+           fun (Ctrl, Node, DHandle) when Ctrl == DistCtrl ->
+                   f_handshake_complete(DistCtrl, Node, DHandle)
+           end}.
+
+f_send(SslSocket, Packet) ->
+    ssl:send(SslSocket, Packet).
+
+f_recv(SslSocket, Length, Timeout) ->
+    case ssl:recv(SslSocket, Length, Timeout) of
+        {ok, Bin} when is_binary(Bin) ->
+            {ok, binary_to_list(Bin)};
+        Other ->
+            Other
+    end.
+
+f_setopts_pre_nodeup(_SslSocket) ->
+    ok.
+
+f_setopts_post_nodeup(_SslSocket) ->
+    ok.
+
+f_getll(DistCtrl) ->
+    {ok, DistCtrl}.
+
+f_address(SslSocket, Node) ->
+    case ssl:peername(SslSocket) of
+        {ok, Address} ->
+            case split_node(Node) of
+                false ->
+                    {error, no_node};
+                Host ->
+                    #net_address{
+                       address=Address, host=Host,
+                       protocol=tls, family=inet}
+            end
+    end.
+
+mf_tick(DistCtrl) ->
+    DistCtrl ! tick,
+    ok.
+
+mf_getstat(SslSocket) ->
+    case ssl:getstat(
+           SslSocket, [recv_cnt, send_cnt, send_pend]) of
+        {ok, Stat} ->
+            split_stat(Stat,0,0,0);
+        Error ->
+            Error
+    end.
+
+mf_setopts(SslSocket, Opts) ->
+    case setopts_filter(Opts) of
+        [] ->
+            ssl:setopts(SslSocket, Opts);
+        Opts1 ->
+            {error, {badopts,Opts1}}
+    end.
+
+mf_getopts(SslSocket, Opts) ->
+    ssl:getopts(SslSocket, Opts).
+
+f_handshake_complete(DistCtrl, Node, DHandle) ->
+    ssl_connection:handshake_complete(DistCtrl, Node, DHandle).
+
+
+setopts_filter(Opts) ->
+    [Opt || {K,_} = Opt <- Opts,
+            K =:= active orelse K =:= deliver orelse K =:= packet].
+
+split_stat([{recv_cnt, R}|Stat], _, W, P) ->
+    split_stat(Stat, R, W, P);
+split_stat([{send_cnt, W}|Stat], R, _, P) ->
+    split_stat(Stat, R, W, P);
+split_stat([{send_pend, P}|Stat], R, W, _) ->
+    split_stat(Stat, R, W, P);
+split_stat([], R, W, P) ->
+    {ok, R, W, P}.
+
+%% -------------------------------------------------------------------------
 
 listen(Name) ->
     gen_listen(inet_tcp, Name).
 
 gen_listen(Driver, Name) ->
-    ssl_tls_dist_proxy:listen(Driver, Name).
+    case inet_tcp_dist:gen_listen(Driver, Name) of
+        {ok, {Socket, Address, Creation}} ->
+            inet:setopts(Socket, [{packet, 4}]),
+            {ok, {Socket, Address#net_address{protocol=tls}, Creation}};
+        Other ->
+            Other
+    end.
+
+%% -------------------------------------------------------------------------
 
 accept(Listen) ->
     gen_accept(inet_tcp, Listen).
 
 gen_accept(Driver, Listen) ->
-    ssl_tls_dist_proxy:accept(Driver, Listen).
+    Kernel = self(),
+    monitor_pid(
+      spawn_opt(
+        fun () ->
+                accept_loop(Driver, Listen, Kernel)
+        end,
+        [link, {priority, max}])).
 
-accept_connection(AcceptPid, Socket, MyNode, Allowed, SetupTime) ->
-    gen_accept_connection(inet_tcp, AcceptPid, Socket, MyNode, Allowed, SetupTime).
+accept_loop(Driver, Listen, Kernel) ->
+    case Driver:accept(Listen) of
+        {ok, Socket} ->
+            Opts = get_ssl_options(server),
+            wait_for_code_server(),
+            case ssl:ssl_accept(
+                   Socket, [{active, false}, {packet, 4}] ++ Opts,
+                   net_kernel:connecttime()) of
+                {ok, #sslsocket{pid = DistCtrl} = SslSocket} ->
+                    monitor_pid(DistCtrl),
+                    trace(
+                      Kernel !
+                          {accept, self(), DistCtrl,
+                           Driver:family(), tls}),
+                    receive
+                        {Kernel, controller, Pid} ->
+                            ok = ssl:controlling_process(SslSocket, Pid),
+                            trace(
+                              Pid ! {self(), controller});
+                        {Kernel, unsupported_protocol} ->
+                            exit(trace(unsupported_protocol))
+                    end,
+                    accept_loop(Driver, Listen, Kernel);
+		{error, {options, _}} = Error ->
+		    %% Bad options: that's probably our fault.
+                    %% Let's log that.
+		    error_logger:error_msg(
+                      "Cannot accept TLS distribution connection: ~s~n",
+                      [ssl:format_error(Error)]),
+                    _ = trace(Error),
+                    gen_tcp:close(Socket);
+		Other ->
+                    _ = trace(Other),
+                    gen_tcp:close(Socket)
+	    end;
+	Error ->
+	    exit(trace(Error))
+    end,
+    accept_loop(Driver, Listen, Kernel).
+
+wait_for_code_server() ->
+    %% This is an ugly hack.  Upgrading a socket to TLS requires the
+    %% crypto module to be loaded.  Loading the crypto module triggers
+    %% its on_load function, which calls code:priv_dir/1 to find the
+    %% directory where its NIF library is.  However, distribution is
+    %% started earlier than the code server, so the code server is not
+    %% necessarily started yet, and code:priv_dir/1 might fail because
+    %% of that, if we receive an incoming connection on the
+    %% distribution port early enough.
+    %%
+    %% If the on_load function of a module fails, the module is
+    %% unloaded, and the function call that triggered loading it fails
+    %% with 'undef', which is rather confusing.
+    %%
+    %% Thus, the accept process will terminate, and be
+    %% restarted by ssl_dist_sup.  However, it won't have any memory
+    %% of being asked by net_kernel to listen for incoming
+    %% connections.  Hence, the node will believe that it's open for
+    %% distribution, but it actually isn't.
+    %%
+    %% So let's avoid that by waiting for the code server to start.
+    case whereis(code_server) of
+	undefined ->
+	    timer:sleep(10),
+	    wait_for_code_server();
+	Pid when is_pid(Pid) ->
+	    ok
+    end.
 
-gen_accept_connection(Driver, AcceptPid, Socket, MyNode, Allowed, SetupTime) ->
+%% -------------------------------------------------------------------------
+
+accept_connection(AcceptPid, DistCtrl, MyNode, Allowed, SetupTime) ->
+    gen_accept_connection(
+      inet_tcp, AcceptPid, DistCtrl, MyNode, Allowed, SetupTime).
+
+gen_accept_connection(
+  Driver, AcceptPid, DistCtrl, MyNode, Allowed, SetupTime) ->
     Kernel = self(),
-    spawn_link(fun() -> do_accept(Driver, Kernel, AcceptPid, Socket,
-				  MyNode, Allowed, SetupTime) end).
+    monitor_pid(
+      spawn_opt(
+        fun() ->
+                do_accept(
+                  Driver, Kernel, AcceptPid, DistCtrl,
+                  MyNode, Allowed, SetupTime)
+        end,
+        [link, {priority, max}])).
+
+do_accept(Driver, Kernel, AcceptPid, DistCtrl, MyNode, Allowed, SetupTime) ->
+    SslSocket = ssl_connection:get_sslsocket(DistCtrl),
+    receive
+	{AcceptPid, controller} ->
+	    Timer = dist_util:start_timer(SetupTime),
+	    case check_ip(Driver, SslSocket) of
+		true ->
+                    HSData0 = hs_data_common(SslSocket),
+                    HSData =
+                        HSData0#hs_data{
+                          kernel_pid = Kernel,
+                          this_node = MyNode,
+                          socket = DistCtrl,
+                          timer = Timer,
+                          this_flags = 0,
+                          allowed = Allowed},
+                    link(DistCtrl),
+		    dist_util:handshake_other_started(trace(HSData));
+		{false,IP} ->
+		    error_logger:error_msg(
+                      "** Connection attempt from "
+                      "disallowed IP ~w ** ~n", [IP]),
+		    ?shutdown2(no_node, trace({disallowed, IP}))
+	    end
+    end.
 
-setup(Node, Type, MyNode, LongOrShortNames,SetupTime) ->
-    gen_setup(inet_tcp, Node, Type, MyNode, LongOrShortNames,SetupTime).
 
-gen_setup(Driver, Node, Type, MyNode, LongOrShortNames,SetupTime) ->
+
+setup(Node, Type, MyNode, LongOrShortNames, SetupTime) ->
+    gen_setup(inet_tcp, Node, Type, MyNode, LongOrShortNames, SetupTime).
+
+gen_setup(Driver, Node, Type, MyNode, LongOrShortNames, SetupTime) ->
     Kernel = self(),
-    spawn_opt(fun() -> do_setup(Driver, Kernel, Node, Type, MyNode, LongOrShortNames, SetupTime) end, [link, {priority, max}]).
-		   
+    monitor_pid(
+      spawn_opt(
+        fun() ->
+                do_setup(
+                  Driver, Kernel, Node, Type,
+                  MyNode, LongOrShortNames, SetupTime)
+        end,
+        [link, {priority, max}])).
+
 do_setup(Driver, Kernel, Node, Type, MyNode, LongOrShortNames, SetupTime) ->
     [Name, Address] = splitnode(Driver, Node, LongOrShortNames),
-    case inet:getaddr(Address, Driver:family()) of
+    case Driver:getaddr(Address) of
 	{ok, Ip} ->
-	    Timer = dist_util:start_timer(SetupTime),
+            Timer = trace(dist_util:start_timer(SetupTime)),
 	    ErlEpmd = net_kernel:epmd_module(),
 	    case ErlEpmd:port_please(Name, Ip) of
 		{port, TcpPort, Version} ->
-		    ?trace("port_please(~p) -> version ~p~n", 
-			   [Node,Version]),
+                    Opts =
+                        trace(
+                          connect_options(
+                            [{server_name_indication, atom_to_list(Node)}
+                             |get_ssl_options(client)])),
 		    dist_util:reset_timer(Timer),
-		    case
-                        ssl_tls_dist_proxy:connect(
-                          Driver, Address, TcpPort,
-                          [{server_name_indication, atom_to_list(Node)}])
-                    of
-			{ok, Socket} ->
-			    HSData = connect_hs_data(Kernel, Node, MyNode, Socket, 
-						     Timer, Version, Ip, TcpPort, Address,
-						     Type),
-			    dist_util:handshake_we_started(HSData);
+                    case ssl:connect(
+                           Address, TcpPort,
+                           [binary, {active, false}, {packet, 4},
+                            Driver:family(), nodelay()] ++ Opts,
+                           net_kernel:connecttime()) of
+			{ok, #sslsocket{pid = DistCtrl} = SslSocket} ->
+                            monitor_pid(DistCtrl),
+                            ok = ssl:controlling_process(SslSocket, self()),
+                            HSData0 = hs_data_common(SslSocket),
+			    HSData =
+                                HSData0#hs_data{
+                                  kernel_pid = Kernel,
+                                  other_node = Node,
+                                  this_node = MyNode,
+                                  socket = DistCtrl,
+                                  timer = Timer,
+                                  this_flags = 0,
+                                  other_version = Version,
+                                  request_type = Type},
+                            link(DistCtrl),
+			    dist_util:handshake_we_started(trace(HSData));
 			Other ->
 			    %% Other Node may have closed since 
 			    %% port_please !
-			    ?trace("other node (~p) "
-				   "closed since port_please.~n", 
-				   [Node]),
-			    ?shutdown2(Node, {shutdown, {connect_failed, Other}})
+			    ?shutdown2(
+                               Node,
+                               trace(
+                                 {ssl_connect_failed, Ip, TcpPort, Other}))
 		    end;
 		Other ->
-		    ?trace("port_please (~p) "
-			   "failed.~n", [Node]),
-		    ?shutdown2(Node, {shutdown, {port_please_failed, Other}})
+		    ?shutdown2(
+                       Node,
+                       trace(
+                         {port_please_failed, ErlEpmd, Name, Ip, Other}))
 	    end;
 	Other ->
-	    ?trace("inet_getaddr(~p) "
-		   "failed (~p).~n", [Node,Other]),
-	    ?shutdown2(Node, {shutdown, {inet_getaddr_failed, Other}})
+	    ?shutdown2(
+               Node,
+               trace({getaddr_failed, Driver, Address, Other}))
     end.
 
 close(Socket) ->
-    gen_tcp:close(Socket),
-    ok.
+    gen_close(inet, Socket).
+
+gen_close(Driver, Socket) ->
+    trace(Driver:close(Socket)).
 
-do_accept(Driver, Kernel, AcceptPid, Socket, MyNode, Allowed, SetupTime) ->
-    process_flag(priority, max),
-    receive
-	{AcceptPid, controller} ->
-	    Timer = dist_util:start_timer(SetupTime),
-	    case check_ip(Driver, Socket) of
-		true ->
-		    HSData = accept_hs_data(Kernel, MyNode, Socket, Timer, Allowed),
-		    dist_util:handshake_other_started(HSData);
-		{false,IP} ->
-		    error_logger:error_msg("** Connection attempt from "
-					   "disallowed IP ~w ** ~n", [IP]),
-		    ?shutdown(no_node)
-	    end
-    end.
 %% ------------------------------------------------------------
 %% Do only accept new connection attempts from nodes at our
 %% own LAN, if the check_ip environment parameter is true.
 %% ------------------------------------------------------------
-check_ip(Driver, Socket) ->
+check_ip(Driver, SslSocket) ->
     case application:get_env(check_ip) of
 	{ok, true} ->
-	    case get_ifs(Socket) of
+	    case get_ifs(SslSocket) of
 		{ok, IFs, IP} ->
 		    check_ip(Driver, IFs, IP);
-		_ ->
-		    ?shutdown(no_node)
+		Other ->
+		    ?shutdown2(
+                       no_node, trace({check_ip_failed, SslSocket, Other}))
 	    end;
 	_ ->
 	    true
     end.
 
-get_ifs(Socket) ->
+check_ip(Driver, [{OwnIP, _, Netmask}|IFs], PeerIP) ->
+    case {Driver:mask(Netmask, PeerIP), Driver:mask(Netmask, OwnIP)} of
+	{M, M} -> true;
+	_      -> check_ip(IFs, PeerIP)
+    end;
+check_ip(_Driver, [], PeerIP) ->
+    {false, PeerIP}.
+
+get_ifs(#sslsocket{fd = {gen_tcp, Socket, _}}) ->
     case inet:peername(Socket) of
 	{ok, {IP, _}} ->
+            %% XXX this is seriously broken for IPv6
 	    case inet:getif(Socket) of
 		{ok, IFs} -> {ok, IFs, IP};
 		Error     -> Error
@@ -169,125 +449,217 @@ get_ifs(Socket) ->
 	    Error
     end.
 
-check_ip(Driver, [{OwnIP, _, Netmask}|IFs], PeerIP) ->
-    case {Driver:mask(Netmask, PeerIP), Driver:mask(Netmask, OwnIP)} of
-	{M, M} -> true;
-	_      -> check_ip(IFs, PeerIP)
-    end;
-check_ip(_Driver, [], PeerIP) ->
-    {false, PeerIP}.
-
 
 %% If Node is illegal terminate the connection setup!!
 splitnode(Driver, Node, LongOrShortNames) ->
-    case split_node(atom_to_list(Node), $@, []) of
-	[Name|Tail] when Tail =/= [] ->
-	    Host = lists:append(Tail),
+    case string:split(atom_to_list(Node), "@") of
+	[Name, Host] when Host =/= [] ->
 	    check_node(Driver, Name, Node, Host, LongOrShortNames);
 	[_] ->
-	    error_logger:error_msg("** Nodename ~p illegal, no '@' character **~n",
-		      [Node]),
-	    ?shutdown(Node);
+	    error_logger:error_msg(
+              "** Nodename ~p illegal, no '@' character **~n",
+              [Node]),
+	    ?shutdown2(Node, trace({illegal_node_n@me, Node}));
 	_ ->
-	    error_logger:error_msg("** Nodename ~p illegal **~n", [Node]),
-	    ?shutdown(Node)
+	    error_logger:error_msg(
+              "** Nodename ~p illegal **~n", [Node]),
+	    ?shutdown2(Node, trace({illegal_node_name, Node}))
     end.
 
 check_node(Driver, Name, Node, Host, LongOrShortNames) ->
-    case split_node(Host, $., []) of
+    case string:split(Host, ".") of
 	[_] when LongOrShortNames == longnames ->
 	    case Driver:parse_address(Host) of
 		{ok, _} ->
 		    [Name, Host];
 		_ ->
-		    error_logger:error_msg("** System running to use "
-					   "fully qualified "
-					   "hostnames **~n"
-					   "** Hostname ~s is illegal **~n",
-					   [Host]),
-		    ?shutdown(Node)
+		    error_logger:error_msg(
+                      "** System running to use "
+                      "fully qualified hostnames **~n"
+                      "** Hostname ~s is illegal **~n",
+                      [Host]),
+		    ?shutdown2(Node, trace({not_longnames, Host}))
 	    end;
-	[_, _ | _] when LongOrShortNames == shortnames ->
-	    error_logger:error_msg("** System NOT running to use fully qualified "
-			      "hostnames **~n"
-		      "** Hostname ~s is illegal **~n",
-		      [Host]),
-	    ?shutdown(Node);
+	[_, _] when LongOrShortNames == shortnames ->
+	    error_logger:error_msg(
+              "** System NOT running to use "
+              "fully qualified hostnames **~n"
+              "** Hostname ~s is illegal **~n",
+              [Host]),
+	    ?shutdown2(Node, trace({not_shortnames, Host}));
 	_ ->
 	    [Name, Host]
     end.
 
-split_node([Chr|T], Chr, Ack) -> 
-    [lists:reverse(Ack)|split_node(T, Chr, [])];
-split_node([H|T], Chr, Ack) -> 
-    split_node(T, Chr, [H|Ack]);
-split_node([], _, Ack) -> 
-    [lists:reverse(Ack)].
-
-connect_hs_data(Kernel, Node, MyNode, Socket, Timer, Version, Ip, TcpPort, Address, Type) ->
-    common_hs_data(Kernel, MyNode, Socket, Timer, 
-		   #hs_data{other_node = Node,
-			    other_version = Version,
-			    f_address = 
-				fun(_,_) ->
-					#net_address{address = {Ip,TcpPort},
-						     host = Address,
-						     protocol = proxy,
-						     family = inet}
-				end,
-			    request_type = Type
-			   }).
-
-accept_hs_data(Kernel, MyNode, Socket, Timer, Allowed) ->
-    common_hs_data(Kernel, MyNode, Socket, Timer, #hs_data{
-					     allowed = Allowed,
-					     f_address = fun get_remote_id/2
-					    }).
-
-common_hs_data(Kernel, MyNode, Socket, Timer, HsData) ->
-    HsData#hs_data{
-      kernel_pid = Kernel,
-      this_node = MyNode,
-      socket = Socket,
-      timer = Timer,
-      this_flags = 0,
-      f_send = 
-	  fun(S,D) -> 
-		  gen_tcp:send(S,D) 
-	  end,
-      f_recv = 
-	  fun(S,N,T) -> 
-		  gen_tcp:recv(S,N,T) 
-	  end,
-      f_setopts_pre_nodeup = 
-	  fun(S) ->
-		  inet:setopts(S, [{active, false}, {packet, 4}])
-	  end,
-		   f_setopts_post_nodeup = 
-	  fun(S) -> 
-		  inet:setopts(S, [{deliver, port},{active, true}])
-	  end,
-      f_getll = 
-	  fun(S) -> 
-		  inet:getll(S) 
-	  end,
-      mf_tick = 
-	  fun(S) -> 
-		  gen_tcp:send(S, <<>>)
-	  end,
-      mf_getstat = 
-	  fun(S) ->
-		  {ok, Stats} = inet:getstat(S, [recv_cnt, send_cnt, send_pend]),
-		  R = proplists:get_value(recv_cnt, Stats, 0),
-		  W = proplists:get_value(send_cnt, Stats, 0),
-		  P = proplists:get_value(send_pend, Stats, 0),
-		  {ok, R,W,P}
-	  end}.
-
-get_remote_id(Socket, _Node) ->
-    case ssl_tls_dist_proxy:get_tcp_address(Socket) of
-        {ok, Address} ->
-	    Address;
-	{error, _Reason} ->
-	    ?shutdown(no_node)
+split_node(Node) when is_atom(Node) ->
+    case string:split(atom_to_list(Node), "@") of
+        [Name, Host] when Name =/= [], Host =/= [] ->
+            Host;
+        _ ->
+            false
+    end;
+split_node(_) ->
+    false.
+
+%% -------------------------------------------------------------------------
+
+connect_options(Opts) ->
+    case application:get_env(kernel, inet_dist_connect_options) of
+	{ok,ConnectOpts} ->
+	    lists:ukeysort(1, ConnectOpts ++ Opts);
+	_ ->
+	    Opts
+    end.
+
+%% we may not always want the nodelay behaviour
+%% for performance reasons
+nodelay() ->
+    case application:get_env(kernel, dist_nodelay) of
+	undefined ->
+	    {nodelay, true};
+	{ok, true} ->
+	    {nodelay, true};
+	{ok, false} ->
+	    {nodelay, false};
+	_ ->
+	    {nodelay, true}
     end.
+
+
+get_ssl_options(Type) ->
+    try ets:lookup(ssl_dist_opts, Type) of
+        [{Type, Opts}] ->
+            [{erl_dist, true} | Opts];
+        _ ->
+            get_ssl_dist_arguments(Type)
+    catch
+        error:badarg ->
+            get_ssl_dist_arguments(Type)
+    end.
+
+get_ssl_dist_arguments(Type) ->
+    case init:get_argument(ssl_dist_opt) of
+	{ok, Args} ->
+	    [{erl_dist, true} | ssl_options(Type, lists:append(Args))];
+	_ ->
+	    [{erl_dist, true}]
+    end.
+
+ssl_options(_,[]) ->
+    [];
+ssl_options(server, ["client_" ++ _, _Value |T]) ->
+    ssl_options(server,T);
+ssl_options(client, ["server_" ++ _, _Value|T]) ->
+    ssl_options(client,T);
+ssl_options(server, ["server_certfile", Value|T]) ->
+    [{certfile, Value} | ssl_options(server,T)];
+ssl_options(client, ["client_certfile", Value | T]) ->
+    [{certfile, Value} | ssl_options(client,T)];
+ssl_options(server, ["server_cacertfile", Value|T]) ->
+    [{cacertfile, Value} | ssl_options(server,T)];
+ssl_options(client, ["client_cacertfile", Value|T]) ->
+    [{cacertfile, Value} | ssl_options(client,T)];
+ssl_options(server, ["server_keyfile", Value|T]) ->
+    [{keyfile, Value} | ssl_options(server,T)];
+ssl_options(client, ["client_keyfile", Value|T]) ->
+    [{keyfile, Value} | ssl_options(client,T)];
+ssl_options(server, ["server_password", Value|T]) ->
+    [{password, Value} | ssl_options(server,T)];
+ssl_options(client, ["client_password", Value|T]) ->
+    [{password, Value} | ssl_options(client,T)];
+ssl_options(server, ["server_verify", Value|T]) ->
+    [{verify, atomize(Value)} | ssl_options(server,T)];
+ssl_options(client, ["client_verify", Value|T]) ->
+    [{verify, atomize(Value)} | ssl_options(client,T)];
+ssl_options(server, ["server_verify_fun", Value|T]) ->
+    [{verify_fun, verify_fun(Value)} | ssl_options(server,T)];
+ssl_options(client, ["client_verify_fun", Value|T]) ->
+    [{verify_fun, verify_fun(Value)} | ssl_options(client,T)];
+ssl_options(server, ["server_crl_check", Value|T]) ->
+    [{crl_check, atomize(Value)} | ssl_options(server,T)];
+ssl_options(client, ["client_crl_check", Value|T]) ->
+    [{crl_check, atomize(Value)} | ssl_options(client,T)];
+ssl_options(server, ["server_crl_cache", Value|T]) ->
+    [{crl_cache, termify(Value)} | ssl_options(server,T)];
+ssl_options(client, ["client_crl_cache", Value|T]) ->
+    [{crl_cache, termify(Value)} | ssl_options(client,T)];
+ssl_options(server, ["server_reuse_sessions", Value|T]) ->
+    [{reuse_sessions, atomize(Value)} | ssl_options(server,T)];
+ssl_options(client, ["client_reuse_sessions", Value|T]) ->
+    [{reuse_sessions, atomize(Value)} | ssl_options(client,T)];
+ssl_options(server, ["server_secure_renegotiate", Value|T]) ->
+    [{secure_renegotiate, atomize(Value)} | ssl_options(server,T)];
+ssl_options(client, ["client_secure_renegotiate", Value|T]) ->
+    [{secure_renegotiate, atomize(Value)} | ssl_options(client,T)];
+ssl_options(server, ["server_depth", Value|T]) ->
+    [{depth, list_to_integer(Value)} | ssl_options(server,T)];
+ssl_options(client, ["client_depth", Value|T]) ->
+    [{depth, list_to_integer(Value)} | ssl_options(client,T)];
+ssl_options(server, ["server_hibernate_after", Value|T]) ->
+    [{hibernate_after, list_to_integer(Value)} | ssl_options(server,T)];
+ssl_options(client, ["client_hibernate_after", Value|T]) ->
+    [{hibernate_after, list_to_integer(Value)} | ssl_options(client,T)];
+ssl_options(server, ["server_ciphers", Value|T]) ->
+    [{ciphers, Value} | ssl_options(server,T)];
+ssl_options(client, ["client_ciphers", Value|T]) ->
+    [{ciphers, Value} | ssl_options(client,T)];
+ssl_options(server, ["server_dhfile", Value|T]) ->
+    [{dhfile, Value} | ssl_options(server,T)];
+ssl_options(server, ["server_fail_if_no_peer_cert", Value|T]) ->
+    [{fail_if_no_peer_cert, atomize(Value)} | ssl_options(server,T)];
+ssl_options(Type, Opts) ->
+    error(malformed_ssl_dist_opt, [Type, Opts]).
+
+atomize(List) when is_list(List) ->
+    list_to_atom(List);
+atomize(Atom) when is_atom(Atom) ->
+    Atom.
+
+termify(String) when is_list(String) ->
+    {ok, Tokens, _} = erl_scan:string(String ++ "."),
+    {ok, Term} = erl_parse:parse_term(Tokens),
+    Term.
+
+verify_fun(Value) ->
+    case termify(Value) of
+	{Mod, Func, State} when is_atom(Mod), is_atom(Func) ->
+	    Fun = fun Mod:Func/3,
+	    {Fun, State};
+	_ ->
+	    error(malformed_ssl_dist_opt, [Value])
+    end.
+
+%% -------------------------------------------------------------------------
+
+%% Trace point
+trace(Term) -> Term.
+
+%% Keep an eye on distribution Pid:s we know of
+monitor_pid(Pid) ->
+    %%spawn(
+    %%  fun () ->
+    %%          MRef = erlang:monitor(process, Pid),
+    %%          receive
+    %%              {'DOWN', MRef, _, _, normal} ->
+    %%                  error_logger:error_report(
+    %%                    [dist_proc_died,
+    %%                     {reason, normal},
+    %%                     {pid, Pid}]);
+    %%              {'DOWN', MRef, _, _, Reason} ->
+    %%                  error_logger:info_report(
+    %%                    [dist_proc_died,
+    %%                     {reason, Reason},
+    %%                     {pid, Pid}])
+    %%          end
+    %%  end),
+    Pid.
+
+dbg() ->
+    dbg:stop(),
+    dbg:tracer(),
+    dbg:p(all, c),
+    dbg:tpl(?MODULE, cx),
+    dbg:tpl(erlang, dist_ctrl_get_data_notification, cx),
+    dbg:tpl(erlang, dist_ctrl_get_data, cx),
+    dbg:tpl(erlang, dist_ctrl_put_data, cx),
+    ok.
diff --git a/lib/ssl/src/ssl.app.src b/lib/ssl/src/ssl.app.src
index 762aa2f8d8..3c6cd254c1 100644
--- a/lib/ssl/src/ssl.app.src
+++ b/lib/ssl/src/ssl.app.src
@@ -37,7 +37,6 @@
 	       %% Erlang Distribution over SSL/TLS
 	       inet_tls_dist,
 	       inet6_tls_dist,
-	       ssl_tls_dist_proxy,
 	       ssl_dist_sup,
                ssl_dist_connection_sup,
                ssl_dist_admin_sup,
@@ -63,7 +62,5 @@
     {applications, [crypto, public_key, kernel, stdlib]},
     {env, []},
     {mod, {ssl_app, []}},
-    {runtime_dependencies, ["stdlib-3.2","public_key-1.5","kernel-3.0",
-			    "erts-7.0","crypto-4.2", "inets-5.10.7"]}]}.
-
-
+    {runtime_dependencies, ["stdlib-3.2","public_key-1.5","kernel-6.0",
+			    "erts-10.0","crypto-4.2", "inets-5.10.7"]}]}.
diff --git a/lib/ssl/src/ssl_cipher.erl b/lib/ssl/src/ssl_cipher.erl
index 18271f325a..b0e38fb9ad 100644
--- a/lib/ssl/src/ssl_cipher.erl
+++ b/lib/ssl/src/ssl_cipher.erl
@@ -377,30 +377,38 @@ psk_suites({3, N}) ->
 psk_suites(N)
   when N >= 3 ->
     [
+     ?TLS_ECDHE_PSK_WITH_AES_256_GCM_SHA384,
      ?TLS_DHE_PSK_WITH_AES_256_GCM_SHA384,
      ?TLS_RSA_PSK_WITH_AES_256_GCM_SHA384,
      ?TLS_PSK_WITH_AES_256_GCM_SHA384,
+     ?TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384,
      ?TLS_DHE_PSK_WITH_AES_256_CBC_SHA384,
      ?TLS_RSA_PSK_WITH_AES_256_CBC_SHA384,
      ?TLS_PSK_WITH_AES_256_CBC_SHA384,
+     ?TLS_ECDHE_PSK_WITH_AES_128_GCM_SHA256,
      ?TLS_DHE_PSK_WITH_AES_128_GCM_SHA256,
      ?TLS_RSA_PSK_WITH_AES_128_GCM_SHA256,
      ?TLS_PSK_WITH_AES_128_GCM_SHA256,
+     ?TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256,
      ?TLS_DHE_PSK_WITH_AES_128_CBC_SHA256,
      ?TLS_RSA_PSK_WITH_AES_128_CBC_SHA256,
      ?TLS_PSK_WITH_AES_128_CBC_SHA256
     ] ++ psk_suites(0);
 
 psk_suites(_) ->
-	[?TLS_DHE_PSK_WITH_AES_256_CBC_SHA,
+	[?TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA,
+	 ?TLS_DHE_PSK_WITH_AES_256_CBC_SHA,
 	 ?TLS_RSA_PSK_WITH_AES_256_CBC_SHA,
 	 ?TLS_PSK_WITH_AES_256_CBC_SHA,
+	 ?TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA,
 	 ?TLS_DHE_PSK_WITH_AES_128_CBC_SHA,
 	 ?TLS_RSA_PSK_WITH_AES_128_CBC_SHA,
 	 ?TLS_PSK_WITH_AES_128_CBC_SHA,
+	 ?TLS_ECDHE_PSK_WITH_3DES_EDE_CBC_SHA,
 	 ?TLS_DHE_PSK_WITH_3DES_EDE_CBC_SHA,
 	 ?TLS_RSA_PSK_WITH_3DES_EDE_CBC_SHA,
 	 ?TLS_PSK_WITH_3DES_EDE_CBC_SHA,
+	 ?TLS_ECDHE_PSK_WITH_RC4_128_SHA,
 	 ?TLS_DHE_PSK_WITH_RC4_128_SHA,
 	 ?TLS_RSA_PSK_WITH_RC4_128_SHA,
 	 ?TLS_PSK_WITH_RC4_128_SHA].
@@ -678,6 +686,22 @@ suite_definition(?TLS_RSA_PSK_WITH_AES_256_CBC_SHA) ->
       cipher => aes_256_cbc, 
       mac => sha, 
       prf => default_prf};
+%%% PSK NULL Cipher Suites RFC 4785
+suite_definition(?TLS_PSK_WITH_NULL_SHA) ->
+    #{key_exchange => psk, 
+      cipher => null, 
+      mac => sha, 
+      prf => default_prf};
+suite_definition(?TLS_DHE_PSK_WITH_NULL_SHA) ->
+    #{key_exchange => dhe_psk,
+      cipher => null, 
+      mac => sha, 
+      prf => default_prf};
+suite_definition(?TLS_RSA_PSK_WITH_NULL_SHA) ->
+    #{key_exchange => rsa_psk,
+      cipher => null, 
+      mac => sha, 
+      prf => default_prf};  
 %%% TLS 1.2 PSK Cipher Suites RFC 5487
 suite_definition(?TLS_PSK_WITH_AES_128_GCM_SHA256) ->
     #{key_exchange => psk, 
@@ -769,6 +793,67 @@ suite_definition(?TLS_RSA_PSK_WITH_NULL_SHA384) ->
       cipher => null, 
       mac => sha384, 
       prf => default_prf};
+%%% ECDHE PSK Cipher Suites RFC 5489
+suite_definition(?TLS_ECDHE_PSK_WITH_RC4_128_SHA) ->
+    #{key_exchange => ecdhe_psk, 
+      cipher => rc4_128, 
+      mac => sha, 
+      prf => default_prf};
+suite_definition(?TLS_ECDHE_PSK_WITH_3DES_EDE_CBC_SHA) ->
+    #{key_exchange => ecdhe_psk, 
+      cipher => '3des_ede_cbc',
+      mac => sha, 
+      prf => default_prf};
+suite_definition(?TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA) ->
+    #{key_exchange => ecdhe_psk, 
+      cipher => aes_128_cbc, 
+      mac => sha, 
+      prf => default_prf};
+suite_definition(?TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA) ->
+    #{key_exchange => ecdhe_psk, 
+      cipher => aes_256_cbc, 
+      mac => sha, 
+      prf => default_prf};
+suite_definition(?TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256) ->
+    #{key_exchange => ecdhe_psk, 
+      cipher => aes_128_cbc, 
+      mac => sha256, 
+      prf => default_prf};
+suite_definition(?TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384) ->
+    #{key_exchange => ecdhe_psk, 
+      cipher => aes_256_cbc, 
+      mac => sha384, 
+      prf => default_prf};
+suite_definition(?TLS_ECDHE_PSK_WITH_NULL_SHA256) ->
+    #{key_exchange => ecdhe_psk, 
+      cipher => null, 
+      mac => sha256, 
+      prf => default_prf};
+suite_definition(?TLS_ECDHE_PSK_WITH_NULL_SHA384) ->
+    #{key_exchange => ecdhe_psk, 
+      cipher => null, mac => sha384, 
+      prf => default_prf};
+%%% ECDHE_PSK with AES-GCM and AES-CCM Cipher Suites, draft-ietf-tls-ecdhe-psk-aead-05
+suite_definition(?TLS_ECDHE_PSK_WITH_AES_128_GCM_SHA256) ->
+    #{key_exchange => ecdhe_psk, 
+      cipher => aes_128_gcm, 
+      mac => null, 
+      prf => sha256};
+suite_definition(?TLS_ECDHE_PSK_WITH_AES_256_GCM_SHA384) ->
+    #{key_exchange => ecdhe_psk, 
+      cipher => aes_256_gcm, 
+      mac => null, 
+      prf => sha384};
+%% suite_definition(?TLS_ECDHE_PSK_WITH_AES_128_CCM_8_SHA256) ->
+%%     #{key_exchange => ecdhe_psk, 
+%%       cipher => aes_128_ccm, 
+%%       mac => null, 
+%%       prf =>sha256};
+%% suite_definition(?TLS_ECDHE_PSK_WITH_AES_128_CCM_SHA256) ->
+%%     #{key_exchange => ecdhe_psk, 
+%%       cipher => aes_256_ccm, 
+%%       mac => null, 
+%%       prf => sha256};
 %%% SRP Cipher Suites RFC 5054
 suite_definition(?TLS_SRP_SHA_WITH_3DES_EDE_CBC_SHA) ->
     #{key_exchange => srp_anon, 
@@ -1283,6 +1368,19 @@ suite(#{key_exchange := rsa_psk,
         cipher := aes_256_cbc, 
         mac := sha}) ->
     ?TLS_RSA_PSK_WITH_AES_256_CBC_SHA;
+%%% PSK NULL Cipher Suites RFC 4785
+suite(#{key_exchange := psk, 
+        cipher := null, 
+        mac := sha}) ->
+    ?TLS_PSK_WITH_NULL_SHA;
+suite(#{key_exchange := dhe_psk, 
+        cipher := null, 
+        mac := sha}) ->
+    ?TLS_DHE_PSK_WITH_NULL_SHA;
+suite(#{key_exchange := rsa_psk, 
+       cipher := null, 
+       mac := sha}) ->
+    ?TLS_RSA_PSK_WITH_NULL_SHA;
 %%% TLS 1.2 PSK Cipher Suites RFC 5487
 suite(#{key_exchange := psk, 
         cipher := aes_128_gcm, 
@@ -1362,6 +1460,60 @@ suite(#{key_exchange := rsa_psk,
        cipher := null, 
        mac := sha384}) ->
     ?TLS_RSA_PSK_WITH_NULL_SHA384;
+%%% ECDHE PSK Cipher Suites RFC 5489
+suite(#{key_exchange := ecdhe_psk, 
+        cipher := rc4_128,
+        mac := sha}) ->
+    ?TLS_ECDHE_PSK_WITH_RC4_128_SHA;
+suite(#{key_exchange := ecdhe_psk, 
+        cipher :='3des_ede_cbc',
+        mac := sha}) ->
+    ?TLS_ECDHE_PSK_WITH_3DES_EDE_CBC_SHA;
+suite(#{key_exchange := ecdhe_psk, 
+        cipher := aes_128_cbc,
+        mac := sha}) ->
+    ?TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA;
+suite(#{key_exchange := ecdhe_psk, 
+        cipher := aes_256_cbc,
+        mac := sha}) ->
+    ?TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA;
+suite(#{key_exchange := ecdhe_psk, 
+       cipher := aes_128_cbc, 
+       mac := sha256}) ->
+    ?TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256;
+suite(#{key_exchange := ecdhe_psk, 
+       cipher := aes_256_cbc, 
+       mac := sha384}) ->
+    ?TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384;
+suite(#{key_exchange := ecdhe_psk, 
+       cipher := null, 
+       mac := sha256}) ->
+    ?TLS_ECDHE_PSK_WITH_NULL_SHA256;
+suite(#{key_exchange := ecdhe_psk, 
+       cipher := null, 
+       mac := sha384}) ->
+    ?TLS_ECDHE_PSK_WITH_NULL_SHA384;
+%%% ECDHE_PSK with AES-GCM and AES-CCM Cipher Suites, draft-ietf-tls-ecdhe-psk-aead-05
+suite(#{key_exchange := ecdhe_psk, 
+       cipher := aes_128_gcm, 
+       mac := null, 
+       prf := sha256}) ->
+    ?TLS_ECDHE_PSK_WITH_AES_128_GCM_SHA256;
+suite(#{key_exchange := ecdhe_psk, 
+       cipher := aes_256_gcm, 
+       mac := null, 
+       prf := sha384}) ->
+    ?TLS_ECDHE_PSK_WITH_AES_256_GCM_SHA384;
+ %% suite(#{key_exchange := ecdhe_psk, 
+ %%        cipher := aes_128_ccm, 
+ %%        mac := null, 
+ %%        prf := sha256}) ->
+ %%    ?TLS_ECDHE_PSK_WITH_AES_128_CCM_8_SHA256;
+ %% suite(#{key_exchange := ecdhe_psk, 
+ %%         cipher := aes_256_ccm, 
+ %%         mac := null, 
+ %%         prf := sha256}) ->
+ %%    ?TLS_ECDHE_PSK_WITH_AES_128_CCM_SHA256;
 %%% SRP Cipher Suites RFC 5054
 suite(#{key_exchange := srp_anon, 
         cipher := '3des_ede_cbc',
@@ -2072,7 +2224,8 @@ is_acceptable_keyexchange(dhe_dss, Algos) ->
 is_acceptable_keyexchange(dhe_rsa, Algos) ->
     proplists:get_bool(dh, Algos) andalso
         proplists:get_bool(rsa, Algos);
-is_acceptable_keyexchange(ecdh_anon, Algos) ->
+is_acceptable_keyexchange(KeyExchange, Algos) when KeyExchange == ecdh_anon;
+                                                   KeyExchange == ecdhe_psk ->
     proplists:get_bool(ecdh, Algos);
 is_acceptable_keyexchange(KeyExchange, Algos) when KeyExchange == ecdh_ecdsa;
                                                    KeyExchange == ecdhe_ecdsa ->
diff --git a/lib/ssl/src/ssl_cipher.hrl b/lib/ssl/src/ssl_cipher.hrl
index 8e8f3d9c67..e5462d8402 100644
--- a/lib/ssl/src/ssl_cipher.hrl
+++ b/lib/ssl/src/ssl_cipher.hrl
@@ -399,6 +399,17 @@
 %%      TLS_RSA_PSK_WITH_AES_256_CBC_SHA      = { 0x00, 0x95 };
 -define(TLS_RSA_PSK_WITH_AES_256_CBC_SHA, <<?BYTE(16#00), ?BYTE(16#95)>>).
 
+%%% PSK NULL Cipher Suites RFC 4785
+
+%%      TLS_PSK_WITH_NULL_SHA      = { 0x00, 0x2C };
+-define(TLS_PSK_WITH_NULL_SHA, <<?BYTE(16#00), ?BYTE(16#2C)>>).
+
+%%      TLS_DHE_PSK_WITH_NULL_SHA  = { 0x00, 0x2D };
+-define(TLS_DHE_PSK_WITH_NULL_SHA, <<?BYTE(16#00), ?BYTE(16#2D)>>).
+
+%%      TLS_RSA_PSK_WITH_NULL_SHA  = { 0x00, 0x2E };
+-define(TLS_RSA_PSK_WITH_NULL_SHA, <<?BYTE(16#00), ?BYTE(16#2E)>>).
+
 %%% TLS 1.2 PSK Cipher Suites RFC 5487
 
 %%      TLS_PSK_WITH_AES_128_GCM_SHA256       = {0x00,0xA8};
@@ -455,6 +466,46 @@
 %%      TLS_RSA_PSK_WITH_NULL_SHA384          = {0x00,0xB9};
 -define(TLS_RSA_PSK_WITH_NULL_SHA384, <<?BYTE(16#00), ?BYTE(16#B9)>>).
 
+%%% ECDHE PSK Cipher Suites RFC 5489
+
+%%      TLS_ECDHE_PSK_WITH_RC4_128_SHA          = {0xC0,0x33};
+-define(TLS_ECDHE_PSK_WITH_RC4_128_SHA, <<?BYTE(16#C0), ?BYTE(16#33)>>).
+
+%%      TLS_ECDHE_PSK_WITH_3DES_EDE_CBC_SHA     = {0xC0,0x34};
+-define(TLS_ECDHE_PSK_WITH_3DES_EDE_CBC_SHA, <<?BYTE(16#C0), ?BYTE(16#34)>>).
+
+%%      TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA      = {0xC0,0x35};
+-define(TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA, <<?BYTE(16#C0), ?BYTE(16#35)>>).
+
+%%      TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA      = {0xC0,0x36};
+-define(TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA, <<?BYTE(16#C0), ?BYTE(16#36)>>).
+
+%%      TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256   = {0xC0,0x37};
+-define(TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256, <<?BYTE(16#C0), ?BYTE(16#37)>>).
+
+%%      TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384   = {0xC0,0x38};
+-define(TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384, <<?BYTE(16#C0), ?BYTE(16#38)>>).
+
+%%      TLS_ECDHE_PSK_WITH_NULL_SHA256          = {0xC0,0x3A};
+-define(TLS_ECDHE_PSK_WITH_NULL_SHA256, <<?BYTE(16#C0), ?BYTE(16#3A)>>).
+
+%%      TLS_ECDHE_PSK_WITH_NULL_SHA384          = {0xC0,0x3B};
+-define(TLS_ECDHE_PSK_WITH_NULL_SHA384, <<?BYTE(16#C0), ?BYTE(16#3B)>>).
+
+%%% ECDHE_PSK with AES-GCM and AES-CCM Cipher Suites, draft-ietf-tls-ecdhe-psk-aead-05
+
+%%      TLS_ECDHE_PSK_WITH_AES_128_GCM_SHA256   = {0xTBD; 0xTBD} {0xD0,0x01};
+-define(TLS_ECDHE_PSK_WITH_AES_128_GCM_SHA256, <<?BYTE(16#D0), ?BYTE(16#01)>>).
+
+%%      TLS_ECDHE_PSK_WITH_AES_256_GCM_SHA384   = {0xTBD; 0xTBD} {0xD0,0x02};
+-define(TLS_ECDHE_PSK_WITH_AES_256_GCM_SHA384, <<?BYTE(16#D0), ?BYTE(16#02)>>).
+
+%%      TLS_ECDHE_PSK_WITH_AES_128_CCM_8_SHA256 = {0xTBD; 0xTBD} {0xD0,0x03};
+-define(TLS_ECDHE_PSK_WITH_AES_128_CCM_8_SHA256, <<?BYTE(16#D0), ?BYTE(16#03)>>).
+
+%%      TLS_ECDHE_PSK_WITH_AES_128_CCM_SHA256   = {0xTBD; 0xTBD} {0xD0,0x05};
+-define(TLS_ECDHE_PSK_WITH_AES_128_CCM_SHA256, <<?BYTE(16#D0), ?BYTE(16#05)>>).
+
 %%% SRP Cipher Suites RFC 5054
 
 %%      TLS_SRP_SHA_WITH_3DES_EDE_CBC_SHA     = { 0xC0,0x1A };
diff --git a/lib/ssl/src/ssl_connection.erl b/lib/ssl/src/ssl_connection.erl
index 98776dcd59..d046145dff 100644
--- a/lib/ssl/src/ssl_connection.erl
+++ b/lib/ssl/src/ssl_connection.erl
@@ -49,7 +49,7 @@
 
 %% Alert and close handling
 -export([handle_own_alert/4, handle_alert/3, 
-	 handle_normal_shutdown/3 
+	 handle_normal_shutdown/3, stop/2, stop_and_reply/3
 	]).
 
 %% Data handling
@@ -61,11 +61,15 @@
 
 %% General gen_statem state functions with extra callback argument 
 %% to determine if it is an SSL/TLS or DTLS gen_statem machine
--export([init/4, error/4, hello/4, abbreviated/4, certify/4, cipher/4, connection/4, downgrade/4]).
+-export([init/4, error/4, hello/4, abbreviated/4, certify/4, cipher/4,
+         connection/4, death_row/4, downgrade/4]).
 
 %% gen_statem callbacks
 -export([terminate/3, format_status/2]).
 
+%% Erlang Distribution export
+-export([get_sslsocket/1, handshake_complete/3]).
+
 %%====================================================================
 %% Setup
 %%====================================================================
@@ -146,8 +150,8 @@ socket_control(Connection, Socket, Pid, Transport) ->
 -spec socket_control(tls_connection | dtls_connection, port(), pid(), atom(), pid()| undefined) -> 
     {ok, #sslsocket{}} | {error, reason()}.  
 %%--------------------------------------------------------------------	    
-socket_control(Connection, Socket, Pid, Transport, udp_listner) ->
-    %% dtls listner process must have the socket control
+socket_control(Connection, Socket, Pid, Transport, udp_listener) ->
+    %% dtls listener process must have the socket control
     {ok, Connection:socket(Pid, Transport, Socket, Connection, undefined)};
 
 socket_control(tls_connection = Connection, Socket, Pid, Transport, ListenTracker) ->
@@ -272,6 +276,13 @@ peer_certificate(ConnectionPid) ->
 renegotiation(ConnectionPid) ->
     call(ConnectionPid, renegotiate). 
 
+
+get_sslsocket(ConnectionPid) ->
+    call(ConnectionPid, get_sslsocket).
+
+handshake_complete(ConnectionPid, Node, DHandle) ->
+    call(ConnectionPid, {handshake_complete, Node, DHandle}).
+
 %%--------------------------------------------------------------------
 -spec prf(pid(), binary() | 'master_secret', binary(),
 	  [binary() | ssl:prf_random()], non_neg_integer()) ->
@@ -305,7 +316,7 @@ handle_own_alert(Alert, Version, StateName,
     catch _:_ ->
 	    ok
     end,
-    {stop, {shutdown, own_alert}}.
+    stop({shutdown, own_alert}, State).
 
 handle_normal_shutdown(Alert, _, #state{socket = Socket,
 					transport_cb = Transport,
@@ -329,24 +340,24 @@ handle_alert(#alert{level = ?FATAL} = Alert, StateName,
 		    protocol_cb = Connection,
 		    ssl_options = SslOpts, start_or_recv_from = From, host = Host,
 		    port = Port, session = Session, user_application = {_Mon, Pid},
-		    role = Role, socket_options = Opts, tracker = Tracker}) ->
+		    role = Role, socket_options = Opts, tracker = Tracker} = State) ->
     invalidate_session(Role, Host, Port, Session),
     log_alert(SslOpts#ssl_options.log_alert, Role, Connection:protocol_name(), 
               StateName, Alert#alert{role = opposite_role(Role)}),
     alert_user(Transport, Tracker, Socket, StateName, Opts, Pid, From, Alert, Role, Connection),
-    {stop, normal};
+    stop(normal, State);
 
 handle_alert(#alert{level = ?WARNING, description = ?CLOSE_NOTIFY} = Alert, 
 	     StateName, State) -> 
     handle_normal_shutdown(Alert, StateName, State),
-    {stop, {shutdown, peer_close}};
+    stop({shutdown, peer_close}, State);
 
 handle_alert(#alert{level = ?WARNING, description = ?NO_RENEGOTIATION} = Alert, StateName, 
 	     #state{role = Role, ssl_options = SslOpts, protocol_cb = Connection, renegotiation = {true, internal}} = State) ->
     log_alert(SslOpts#ssl_options.log_alert, Role, 
               Connection:protocol_name(), StateName, Alert#alert{role = opposite_role(Role)}),
     handle_normal_shutdown(Alert, StateName, State),
-    {stop, {shutdown, peer_close}};
+    stop({shutdown, peer_close}, State);
 
 handle_alert(#alert{level = ?WARNING, description = ?NO_RENEGOTIATION} = Alert, StateName, 
 	     #state{role = Role,
@@ -371,7 +382,7 @@ handle_alert(#alert{level = ?WARNING} = Alert, StateName,
 %%====================================================================
 %% Data handling
 %%====================================================================
-write_application_data(Data0, From, 
+write_application_data(Data0, {FromPid, _} = From,
 		       #state{socket = Socket,
 			      negotiated_version = Version,
 			      protocol_cb = Connection,
@@ -386,10 +397,19 @@ write_application_data(Data0, From,
 	    Connection:renegotiate(State#state{renegotiation = {true, internal}}, 
 			[{next_event, {call, From}, {application_data, Data0}}]);
 	false ->
-	    {Msgs, ConnectionStates} = Connection:encode_data(Data, Version, ConnectionStates0),
-	    Result = Connection:send(Transport, Socket, Msgs),
-	        ssl_connection:hibernate_after(connection, State#state{connection_states = ConnectionStates}, 
-					       [{reply, From, Result}])
+	    {Msgs, ConnectionStates} =
+                Connection:encode_data(Data, Version, ConnectionStates0),
+            NewState = State#state{connection_states = ConnectionStates},
+	    case Connection:send(Transport, Socket, Msgs) of
+                ok when FromPid =:= self() ->
+                    hibernate_after(connection, NewState, []);
+                Error when FromPid =:= self() ->
+                    stop({shutdown, Error}, NewState);
+                ok ->
+                    hibernate_after(connection, NewState, [{reply, From, ok}]);
+                Result ->
+                    hibernate_after(connection, NewState, [{reply, From, Result}])
+            end
     end.
 
 read_application_data(Data, #state{user_application = {_Mon, Pid},
@@ -409,30 +429,57 @@ read_application_data(Data, #state{user_application = {_Mon, Pid},
 	      end,
     case get_data(SOpts, BytesToRead, Buffer1) of
 	{ok, ClientData, Buffer} -> % Send data
-	    SocketOpt = deliver_app_data(Transport, Socket, SOpts, 
-					 ClientData, Pid, RecvFrom, Tracker, Connection),
-	    cancel_timer(Timer),
-	    State = State0#state{user_data_buffer = Buffer,
-				 start_or_recv_from = undefined,
-				 timer = undefined,
-				 bytes_to_read = undefined,
-				 socket_options = SocketOpt 
-				},
-	    if
-		SocketOpt#socket_options.active =:= false; Buffer =:= <<>> -> 
-		    %% Passive mode, wait for active once or recv
-		    %% Active and empty, get more data
-		    Connection:next_record_if_active(State);
-	 	true -> %% We have more data
- 		    read_application_data(<<>>, State)
-	    end;
+            case State0 of
+                #state{
+                   ssl_options = #ssl_options{erl_dist = true},
+                  protocol_specific = #{d_handle := DHandle}} ->
+                    State =
+                        State0#state{
+                          user_data_buffer = Buffer,
+                          bytes_to_read = undefined},
+                    try erlang:dist_ctrl_put_data(DHandle, ClientData) of
+                        _
+                          when SOpts#socket_options.active =:= false;
+                               Buffer =:= <<>> ->
+                            %% Passive mode, wait for active once or recv
+                            %% Active and empty, get more data
+                            Connection:next_record_if_active(State);
+                        _ -> %% We have more data
+                            read_application_data(<<>>, State)
+                    catch error:_ ->
+                            death_row(State, disconnect)
+                    end;
+                _ ->
+                    SocketOpt =
+                        deliver_app_data(
+                          Transport, Socket, SOpts,
+                          ClientData, Pid, RecvFrom, Tracker, Connection),
+                    cancel_timer(Timer),
+                    State =
+                        State0#state{
+                          user_data_buffer = Buffer,
+                          start_or_recv_from = undefined,
+                          timer = undefined,
+                          bytes_to_read = undefined,
+                          socket_options = SocketOpt
+                         },
+                    if
+                        SocketOpt#socket_options.active =:= false;
+                        Buffer =:= <<>> ->
+                            %% Passive mode, wait for active once or recv
+                            %% Active and empty, get more data
+                            Connection:next_record_if_active(State);
+                        true -> %% We have more data
+                            read_application_data(<<>>, State)
+                    end
+            end;
 	{more, Buffer} -> % no reply, we need more data
 	    Connection:next_record(State0#state{user_data_buffer = Buffer});
 	{passive, Buffer} ->
 	    Connection:next_record_if_active(State0#state{user_data_buffer = Buffer});
 	{error,_Reason} -> %% Invalid packet in packet mode
 	    deliver_packet_error(Transport, Socket, SOpts, Buffer1, Pid, RecvFrom, Tracker, Connection),
-	    {stop, normal, State0}
+            stop(normal, State0)
     end.
 %%====================================================================
 %% Help functions for tls|dtls_connection.erl
@@ -524,11 +571,17 @@ init({call, From}, {start, {Opts, EmOpts}, Timeout},
             socket_options = SockOpts} = State0, Connection) ->
     try 
         SslOpts = ssl:handle_options(Opts, OrigSSLOptions),
+        case SslOpts of
+            #ssl_options{erl_dist = true} ->
+                process_flag(priority, max);
+            _ ->
+                ok
+        end,
 	State = ssl_config(SslOpts, Role, State0),
 	init({call, From}, {start, Timeout}, 
 	     State#state{ssl_options = SslOpts, socket_options = new_emulated(EmOpts, SockOpts)}, Connection)
     catch throw:Error ->
-	    {stop_and_reply, normal, {reply, From, {error, Error}}}
+	    stop_and_reply(normal, {reply, From, {error, Error}}, State0)
     end;
 init({call, From}, Msg, State, Connection) ->
     handle_call(Msg, From, ?FUNCTION_NAME, State, Connection);
@@ -685,7 +738,7 @@ certify(internal, #server_key_exchange{exchange_keys = Keys},
   when Alg == dhe_dss; Alg == dhe_rsa;
        Alg == ecdhe_rsa; Alg == ecdhe_ecdsa;
        Alg == dh_anon; Alg == ecdh_anon;
-       Alg == psk; Alg == dhe_psk; Alg == rsa_psk;
+       Alg == psk; Alg == dhe_psk; Alg == ecdhe_psk; Alg == rsa_psk;
        Alg == srp_dss; Alg == srp_rsa; Alg == srp_anon ->
 
     Params = ssl_handshake:decode_server_key(Keys, Alg, ssl:tls_version(Version)),
@@ -709,6 +762,14 @@ certify(internal, #server_key_exchange{exchange_keys = Keys},
 						Version, ?FUNCTION_NAME, State)
 	    end
     end;
+certify(internal, #certificate_request{},
+	#state{role = client, negotiated_version = Version,
+               key_algorithm = Alg} = State, _)
+  when Alg == dh_anon; Alg == ecdh_anon;
+       Alg == psk; Alg == dhe_psk; Alg == ecdhe_psk; Alg == rsa_psk;
+       Alg == srp_dss; Alg == srp_rsa; Alg == srp_anon ->
+    handle_own_alert(?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE),
+                     Version, ?FUNCTION_NAME, State);
 certify(internal, #certificate_request{} = CertRequest,
 	#state{session = #session{own_certificate = Cert},
 	       role = client,
@@ -895,7 +956,7 @@ cipher(Type, Msg, State, Connection) ->
 		 #state{}, tls_connection | dtls_connection) ->
 			gen_statem:state_function_result().
 %%--------------------------------------------------------------------
-connection({call, From}, {application_data, Data},  
+connection({call, {FromPid, _} = From}, {application_data, Data},
 	   #state{protocol_cb = Connection} = State, Connection) ->
     %% We should look into having a worker process to do this to 
     %% parallize send and receive decoding and not block the receiver
@@ -903,7 +964,13 @@ connection({call, From}, {application_data, Data},
      try
 	 write_application_data(Data, From, State)
      catch throw:Error ->
-	     hibernate_after(?FUNCTION_NAME, State, [{reply, From, Error}])
+             case self() of
+                 FromPid ->
+                     stop({shutdown, Error}, State);
+                 _ ->
+                     hibernate_after(
+                       ?FUNCTION_NAME, State, [{reply, From, Error}])
+             end
      end;
 connection({call, RecvFrom}, {recv, N, Timeout},  
 	   #state{protocol_cb = Connection,  socket_options =
@@ -931,8 +998,64 @@ connection({call, From}, negotiated_protocol,
 	   #state{negotiated_protocol = SelectedProtocol} = State, _) ->
     hibernate_after(?FUNCTION_NAME, State,
 		    [{reply, From, {ok, SelectedProtocol}}]);
+connection(
+  {call, From}, {handshake_complete, _Node, DHandle},
+  #state{
+     ssl_options = #ssl_options{erl_dist = true},
+     socket_options = SockOpts,
+     protocol_specific = ProtocolSpecific} = State,
+  Connection) ->
+    %% From now on we execute on normal priority
+    process_flag(priority, normal),
+    try erlang:dist_ctrl_get_data_notification(DHandle) of
+        _ ->
+            NewState =
+                State#state{
+                  socket_options =
+                      SockOpts#socket_options{active = true},
+                  protocol_specific =
+                      ProtocolSpecific#{d_handle => DHandle}},
+            {Record, NewerState} = Connection:next_record_if_active(NewState),
+            Connection:next_event(connection, Record, NewerState, [{reply, From, ok}])
+    catch error:_ ->
+            death_row(State, disconnect)
+    end;
 connection({call, From}, Msg, State, Connection) ->
     handle_call(Msg, From, ?FUNCTION_NAME, State, Connection);
+connection(
+  info, dist_data = Msg,
+  #state{
+     ssl_options = #ssl_options{erl_dist = true},
+     protocol_specific = #{d_handle := DHandle}} = State,
+  _) ->
+    eat_msgs(Msg),
+    try send_dist_data(?FUNCTION_NAME, State, DHandle, [])
+    catch error:_ ->
+            death_row(State, disconnect)
+    end;
+connection(
+  info, {send, From, Ref, Data},
+  #state{
+     ssl_options = #ssl_options{erl_dist = true},
+     protocol_specific = #{d_handle := _}},
+  _) ->
+    %% This is for testing only!
+    %%
+    %% Needed by some OTP distribution
+    %% test suites...
+    From ! {Ref, ok},
+    {keep_state_and_data,
+     [{next_event, {call, {self(), undefined}},
+       {application_data, iolist_to_binary(Data)}}]};
+connection(
+  info, tick = Msg,
+  #state{
+     ssl_options = #ssl_options{erl_dist = true},
+     protocol_specific = #{d_handle := _}},
+  _) ->
+    eat_msgs(Msg),
+    {keep_state_and_data,
+     [{next_event, {call, {self(), undefined}}, {application_data, <<>>}}]};
 connection(info, Msg, State, _) ->
     handle_info(Msg, ?FUNCTION_NAME, State);
 connection(internal, {recv, _}, State, Connection) ->
@@ -941,6 +1064,32 @@ connection(Type, Msg, State, Connection) ->
     handle_common_event(Type, Msg, ?FUNCTION_NAME, State, Connection).
 
 %%--------------------------------------------------------------------
+-spec death_row(gen_statem:event_type(), term(),
+		#state{}, tls_connection | dtls_connection) ->
+		       gen_statem:state_function_result().
+%%--------------------------------------------------------------------
+%% We just wait for the owner to die which triggers the monitor,
+%% or the socket may die too
+death_row(
+  info, {'DOWN', MonitorRef, _, _, Reason},
+  #state{user_application={MonitorRef,_Pid}},
+  _) ->
+    {stop, {shutdown, Reason}};
+death_row(
+  info, {'EXIT', Socket, Reason}, #state{socket = Socket}, _) ->
+    {stop, {shutdown, Reason}};
+death_row(state_timeout, Reason, _State, _Connection) ->
+    {stop, {shutdown,Reason}};
+death_row(_Type, _Msg, _State, _Connection) ->
+    %% Waste all other events
+    keep_state_and_data.
+
+%% State entry function
+death_row(State, Reason) ->
+    {next_state, death_row, State,
+     [{state_timeout, 5000, Reason}]}.
+
+%%--------------------------------------------------------------------
 -spec downgrade(gen_statem:event_type(), term(), 
 		#state{}, tls_connection | dtls_connection) ->
 		       gen_statem:state_function_result().
@@ -951,10 +1100,10 @@ downgrade(internal, #alert{description = ?CLOSE_NOTIFY},
     tls_socket:setopts(Transport, Socket, [{active, false}, {packet, 0}, {mode, binary}]),
     Transport:controlling_process(Socket, Pid),
     gen_statem:reply(From, {ok, Socket}),
-    {stop, normal, State};
+    stop(normal, State);
 downgrade(timeout, downgrade, #state{downgrade = {_, From}} = State, _) ->
     gen_statem:reply(From, {error, timeout}),
-    {stop, normal, State};
+    stop(normal, State);
 downgrade(Type, Event, State, Connection) ->
     handle_common_event(Type, Event, ?FUNCTION_NAME, State, Connection).
 
@@ -969,7 +1118,7 @@ handle_common_event(internal, {handshake, {#hello_request{} = Handshake, _}}, co
 handle_common_event(internal, {handshake, {#hello_request{}, _}}, StateName, #state{role = client}, _) 
   when StateName =/= connection ->
     {keep_state_and_data};
-handle_common_event(internal, {handshake, {Handshake, Raw}}, StateName, 
+handle_common_event(internal, {handshake, {Handshake, Raw}}, StateName,
 		    #state{tls_handshake_history = Hs0,
 			   ssl_options = #ssl_options{v2_hello_compatible = V2HComp}} = State0, 
 		    Connection) ->
@@ -988,8 +1137,8 @@ handle_common_event(timeout, hibernate, _, _, _) ->
     {keep_state_and_data, [hibernate]};
 handle_common_event(internal, {application_data, Data}, StateName, State0, Connection) ->
     case read_application_data(Data, State0) of
-	{stop, Reason, State} ->
-   	    {stop, Reason, State};
+	{stop, _, _} = Stop->
+            Stop;
 	{Record, State} ->
    	    Connection:next_event(StateName, Record, State)
     end;
@@ -1018,13 +1167,14 @@ handle_call({close, _} = Close, From, StateName, State, Connection) ->
     %% Run terminate before returning so that the reuseaddr
     %% inet-option works properly
     Result = Connection:terminate(Close, StateName, State#state{terminated = true}),
-    {stop_and_reply, {shutdown, normal},  
-     {reply, From, Result}, State};
+    stop_and_reply(
+      {shutdown, normal},
+      {reply, From, Result}, State);
 handle_call({shutdown, How0}, From, _,
 	    #state{transport_cb = Transport,
 		   negotiated_version = Version,
 		   connection_states = ConnectionStates,
-		   socket = Socket}, Connection) ->
+		   socket = Socket} = State, Connection) ->
     case How0 of
 	How when How == write; How == both ->	    
 	    Alert = ?ALERT_REC(?WARNING, ?CLOSE_NOTIFY),
@@ -1040,7 +1190,7 @@ handle_call({shutdown, How0}, From, _,
 	    {keep_state_and_data, [{reply, From, ok}]};
 	Error ->
 	    gen_statem:reply(From, {error, Error}),
-	    {stop, normal}
+            stop(normal, State)
     end;
 handle_call({recv, _N, _Timeout}, From, _,  
 		  #state{socket_options = 
@@ -1075,6 +1225,15 @@ handle_call({set_opts, Opts0}, From, StateName,
     
 handle_call(renegotiate, From, StateName, _, _) when StateName =/= connection ->
     {keep_state_and_data, [{reply, From, {error, already_renegotiating}}]};
+
+handle_call(
+  get_sslsocket, From, _StateName,
+  #state{transport_cb = Transport, socket = Socket, tracker = Tracker},
+  Connection) ->
+    SslSocket =
+        Connection:socket(self(), Transport, Socket, Connection, Tracker),
+    {keep_state_and_data, [{reply, From, SslSocket}]};
+
 handle_call({prf, Secret, Label, Seed, WantedLength}, From, _,
 	    #state{connection_states = ConnectionStates,
 		   negotiated_version = Version}, _) ->
@@ -1111,29 +1270,50 @@ handle_info({ErrorTag, Socket, econnaborted}, StateName,
 		   tracker = Tracker} = State)  when StateName =/= connection ->
     alert_user(Transport, Tracker,Socket, 
 	       StartFrom, ?ALERT_REC(?FATAL, ?CLOSE_NOTIFY), Role, Connection),
-    {stop, normal, State};
+    stop(normal, State);
+
 handle_info({ErrorTag, Socket, Reason}, StateName, #state{socket = Socket,
 							  error_tag = ErrorTag} = State)  ->
     Report = io_lib:format("SSL: Socket error: ~p ~n", [Reason]),
-    error_logger:info_report(Report),
+    error_logger:error_report(Report),
     handle_normal_shutdown(?ALERT_REC(?FATAL, ?CLOSE_NOTIFY), StateName, State),
-    {stop, normal, State};
-handle_info({'DOWN', MonitorRef, _, _, _}, _, 
-	    State = #state{user_application={MonitorRef,_Pid}}) ->
-    {stop, normal, State};   
+    stop(normal, State);
+
+handle_info(
+  {'DOWN', MonitorRef, _, _, Reason}, _,
+  #state{
+     user_application = {MonitorRef, _Pid},
+     ssl_options = #ssl_options{erl_dist = true}}) ->
+    {stop, {shutdown, Reason}};
+handle_info(
+  {'DOWN', MonitorRef, _, _, _}, _,
+  #state{user_application = {MonitorRef, _Pid}}) ->
+    {stop, normal};
+handle_info(
+  {'EXIT', Pid, _Reason}, StateName,
+  #state{user_application = {_MonitorRef, Pid}} = State) ->
+    %% It seems the user application has linked to us
+    %% - ignore that and let the monitor handle this
+    {next_state, StateName, State};
+
 %%% So that terminate will be run when supervisor issues shutdown
 handle_info({'EXIT', _Sup, shutdown}, _StateName, State) ->
-    {stop, shutdown, State};
+    stop(shutdown, State);
 handle_info({'EXIT', Socket, normal}, _StateName, #state{socket = Socket} = State) ->
     %% Handle as transport close"
-    {stop, {shutdown, transport_closed}, State};
+    stop({shutdown, transport_closed}, State);
+handle_info({'EXIT', Socket, Reason}, _StateName, #state{socket = Socket} = State) ->
+    stop({shutdown, Reason}, State);
+
 handle_info(allow_renegotiate, StateName, State) ->
     {next_state, StateName, State#state{allow_renegotiate = true}};
 
 handle_info({cancel_start_or_recv, StartFrom}, StateName,
 	    #state{renegotiation = {false, first}} = State) when StateName =/= connection ->
-    {stop_and_reply, {shutdown, user_timeout},  
-     {reply, StartFrom, {error, timeout}}, State#state{timer = undefined}};
+    stop_and_reply(
+      {shutdown, user_timeout},
+      {reply, StartFrom, {error, timeout}},
+      State#state{timer = undefined});
 handle_info({cancel_start_or_recv, RecvFrom}, StateName, 
 	    #state{start_or_recv_from = RecvFrom} = State) when RecvFrom =/= undefined ->
     {next_state, StateName, State#state{start_or_recv_from = undefined,
@@ -1447,6 +1627,14 @@ certify_client_key_exchange(#client_dhe_psk_identity{} = ClientKey,
     PremasterSecret = 
 	ssl_handshake:premaster_secret(ClientKey, ServerDhPrivateKey, Params, PSKLookup),
     calculate_master_secret(PremasterSecret, State0, Connection, certify, cipher);
+certify_client_key_exchange(#client_ecdhe_psk_identity{} = ClientKey,
+			    #state{diffie_hellman_keys = ServerEcDhPrivateKey,
+				   ssl_options =
+				       #ssl_options{user_lookup_fun = PSKLookup}} = State,
+			    Connection) ->
+    PremasterSecret =
+	ssl_handshake:premaster_secret(ClientKey, ServerEcDhPrivateKey, PSKLookup),
+    calculate_master_secret(PremasterSecret, State, Connection, certify, cipher);
 certify_client_key_exchange(#client_rsa_psk_identity{} = ClientKey,
 			    #state{private_key = Key,
 				   ssl_options = 
@@ -1465,6 +1653,7 @@ certify_server(#state{key_algorithm = Algo} = State, _) when Algo == dh_anon;
 							     Algo == ecdh_anon; 
 							     Algo == psk; 
 							     Algo == dhe_psk; 
+							     Algo == ecdhe_psk; 
 							     Algo == srp_anon  ->
     State;
 certify_server(#state{cert_db = CertDbHandle,
@@ -1566,6 +1755,27 @@ key_exchange(#state{role = server, key_algorithm = dhe_psk,
 				       PrivateKey}),
     State = Connection:queue_handshake(Msg, State0),
     State#state{diffie_hellman_keys = DHKeys};
+key_exchange(#state{role = server, key_algorithm = ecdhe_psk,
+		    ssl_options = #ssl_options{psk_identity = PskIdentityHint},
+		    hashsign_algorithm = HashSignAlgo,
+		    private_key = PrivateKey,
+                    session = #session{ecc = ECCCurve},
+		    connection_states = ConnectionStates0,
+		    negotiated_version = Version
+		   } = State0, Connection) ->
+    ECDHKeys = public_key:generate_key(ECCCurve),
+    #{security_parameters := SecParams} =
+	ssl_record:pending_connection_state(ConnectionStates0, read),
+    #security_parameters{client_random = ClientRandom,
+			 server_random = ServerRandom} = SecParams,
+    Msg =  ssl_handshake:key_exchange(server, ssl:tls_version(Version),
+				      {ecdhe_psk,
+				       PskIdentityHint, ECDHKeys,
+				       HashSignAlgo, ClientRandom,
+				       ServerRandom,
+				       PrivateKey}),
+    State = Connection:queue_handshake(Msg, State0),
+    State#state{diffie_hellman_keys = ECDHKeys};
 key_exchange(#state{role = server, key_algorithm = rsa_psk,
 		    ssl_options = #ssl_options{psk_identity = undefined}} = State, _) ->
     State;
@@ -1659,6 +1869,17 @@ key_exchange(#state{role = client,
 				      {dhe_psk, 
 				       SslOpts#ssl_options.psk_identity, DhPubKey}),
     Connection:queue_handshake(Msg, State0);
+
+key_exchange(#state{role = client,
+		    ssl_options = SslOpts,
+		    key_algorithm = ecdhe_psk,
+		    negotiated_version = Version,
+		    diffie_hellman_keys = ECDHKeys} = State0, Connection) ->
+    Msg =  ssl_handshake:key_exchange(client, ssl:tls_version(Version),
+				      {ecdhe_psk,
+				       SslOpts#ssl_options.psk_identity, ECDHKeys}),
+    Connection:queue_handshake(Msg, State0);
+
 key_exchange(#state{role = client,
 		    ssl_options = SslOpts,
 		    key_algorithm = rsa_psk,
@@ -1713,6 +1934,12 @@ rsa_psk_key_exchange(Version, PskIdentity, PremasterSecret,
 rsa_psk_key_exchange(_, _, _, _) ->
     throw (?ALERT_REC(?FATAL,?HANDSHAKE_FAILURE, pub_key_is_not_rsa)).
 
+request_client_cert(#state{key_algorithm = Alg} = State, _)
+  when Alg == dh_anon; Alg == ecdh_anon;
+       Alg == psk; Alg == dhe_psk; Alg == ecdhe_psk; Alg == rsa_psk;
+       Alg == srp_dss; Alg == srp_rsa; Alg == srp_anon ->
+    State;
+
 request_client_cert(#state{ssl_options = #ssl_options{verify = verify_peer, 
 						      signature_algs = SupportedHashSigns},
 			   connection_states = ConnectionStates0,
@@ -1834,6 +2061,18 @@ calculate_secret(#server_dhe_psk_params{
     calculate_master_secret(PremasterSecret, State#state{diffie_hellman_keys = Keys},
 			    Connection, certify, certify);
 
+calculate_secret(#server_ecdhe_psk_params{
+                    dh_params = #server_ecdh_params{curve = ECCurve}} = ServerKey,
+                 #state{ssl_options = #ssl_options{user_lookup_fun = PSKLookup}} = 
+		     State=#state{session=Session}, Connection) ->
+    ECDHKeys = public_key:generate_key(ECCurve),
+
+    PremasterSecret = ssl_handshake:premaster_secret(ServerKey, ECDHKeys, PSKLookup),
+    calculate_master_secret(PremasterSecret,
+			    State#state{diffie_hellman_keys = ECDHKeys,
+					session = Session#session{ecc = ECCurve}},
+			    Connection, certify, certify);
+
 calculate_secret(#server_srp_params{srp_n = Prime, srp_g = Generator} = ServerKey,
 		 #state{ssl_options = #ssl_options{srp_identity = SRPId}} = State, 
 		 Connection) ->
@@ -1918,6 +2157,7 @@ is_anonymous(Algo) when Algo == dh_anon;
 			Algo == ecdh_anon;
 			Algo == psk;
 			Algo == dhe_psk;
+			Algo == ecdhe_psk;
 			Algo == rsa_psk;
 			Algo == srp_anon ->
     true;
@@ -2217,8 +2457,8 @@ handle_active_option(_, connection = StateName0, To, Reply, #state{protocol_cb =
 	    hibernate_after(StateName, State, [{reply, To, Reply}]);
 	{next_state, StateName, State, Actions} -> 
 	    hibernate_after(StateName, State, [{reply, To, Reply} | Actions]);
-	{stop, Reason, State} ->
-	    {stop, Reason, State}
+	{stop, _, _} = Stop ->
+	    Stop
     end;
 handle_active_option(_, StateName, To, Reply, #state{user_data_buffer = <<>>} = State) ->
     %% Active once already set 
@@ -2227,8 +2467,8 @@ handle_active_option(_, StateName, To, Reply, #state{user_data_buffer = <<>>} =
 %% user_data_buffer =/= <<>>
 handle_active_option(_, StateName0, To, Reply, #state{protocol_cb = Connection} = State0) -> 
     case read_application_data(<<>>, State0) of
-	{stop, Reason, State} ->
-	    {stop, Reason, State};
+	{stop, _, _} = Stop ->
+	    Stop;
 	{Record, State1} ->
 	    %% Note: Renogotiation may cause StateName0 =/= StateName
 	    case Connection:next_event(StateName0, Record, State1) of
@@ -2386,7 +2626,8 @@ send_or_reply(_, Pid, _From, Data) ->
     send_user(Pid, Data).
 
 send_user(Pid, Msg) ->
-    Pid ! Msg.
+    Pid ! Msg,
+    ok.
 
 alert_user(Transport, Tracker, Socket, connection, Opts, Pid, From, Alert, Role, Connection) ->
     alert_user(Transport, Tracker, Socket, Opts#socket_options.active, Pid, From, Alert, Role, Connection);
@@ -2479,3 +2720,42 @@ new_emulated([], EmOpts) ->
     EmOpts;
 new_emulated(NewEmOpts, _) ->
     NewEmOpts.
+%%---------------Erlang distribution --------------------------------------
+
+send_dist_data(StateName, State, DHandle, Acc) ->
+    case erlang:dist_ctrl_get_data(DHandle) of
+        none ->
+            erlang:dist_ctrl_get_data_notification(DHandle),
+            hibernate_after(StateName, State, lists:reverse(Acc));
+        Data ->
+            send_dist_data(
+              StateName, State, DHandle,
+              [{next_event, {call, {self(), undefined}}, {application_data, Data}}
+               |Acc])
+    end.
+
+%% Overload mitigation
+eat_msgs(Msg) ->
+    receive Msg -> eat_msgs(Msg)
+    after 0 -> ok
+    end.
+
+%% When acting as distribution controller map the exit reason
+%% to follow the documented nodedown_reason for net_kernel
+stop(Reason, State) ->
+    {stop, erl_dist_stop_reason(Reason, State), State}.
+
+stop_and_reply(Reason, Replies, State) ->
+    {stop_and_reply, erl_dist_stop_reason(Reason, State), Replies, State}.
+
+erl_dist_stop_reason(
+  Reason, #state{ssl_options = #ssl_options{erl_dist = true}}) ->
+    case Reason of
+        normal ->
+            %% We can not exit with normal since that will not bring
+            %% down the rest of the distribution processes
+            {shutdown, normal};
+        _ -> Reason
+    end;
+erl_dist_stop_reason(Reason, _State) ->
+    Reason.
diff --git a/lib/ssl/src/ssl_dist_sup.erl b/lib/ssl/src/ssl_dist_sup.erl
index e92f3d3979..bea67935d8 100644
--- a/lib/ssl/src/ssl_dist_sup.erl
+++ b/lib/ssl/src/ssl_dist_sup.erl
@@ -60,8 +60,7 @@ start_link() ->
 init([]) ->    
     AdminSup = ssl_admin_child_spec(),
     ConnectionSup = ssl_connection_sup(),
-    ProxyServer = proxy_server_child_spec(),
-    {ok, {{one_for_all, 10, 3600}, [AdminSup, ProxyServer, ConnectionSup]}}.
+    {ok, {{one_for_all, 10, 3600}, [AdminSup, ConnectionSup]}}.
 
 %%--------------------------------------------------------------------
 %%% Internal functions
@@ -84,15 +83,6 @@ ssl_connection_sup() ->
     Type = supervisor,
     {Name, StartFunc, Restart, Shutdown, Type, Modules}.
 
-proxy_server_child_spec() ->
-    Name = ssl_tls_dist_proxy,  
-    StartFunc = {ssl_tls_dist_proxy, start_link, []},
-    Restart = permanent, 
-    Shutdown = 4000,
-    Modules = [ssl_tls_dist_proxy],
-    Type = worker,
-    {Name, StartFunc, Restart, Shutdown, Type, Modules}.
-
 consult(File) ->
     case erl_prim_loader:get_file(File) of
         {ok, Binary, _FullName} ->
diff --git a/lib/ssl/src/ssl_handshake.erl b/lib/ssl/src/ssl_handshake.erl
index fd437f62d2..1ef298083a 100644
--- a/lib/ssl/src/ssl_handshake.erl
+++ b/lib/ssl/src/ssl_handshake.erl
@@ -192,6 +192,7 @@ certificate_request(CipherSuite, CertDbHandle, CertDbRef, HashSigns, Version) ->
 		   {ecdh, #'ECPrivateKey'{}} |
 		   {psk, binary()} |
 		   {dhe_psk, binary(), binary()} |
+		   {ecdhe_psk, binary(), #'ECPrivateKey'{}} |
 		   {srp, {binary(), binary()}, #srp_user{}, {HashAlgo::atom(), SignAlgo::atom()},
 		   binary(), binary(), public_key:private_key()}) ->
     #client_key_exchange{} | #server_key_exchange{}.
@@ -229,6 +230,13 @@ key_exchange(client, _Version, {dhe_psk, Identity, PublicKey}) ->
 		dh_public = PublicKey}
 	       };
 
+key_exchange(client, _Version, {ecdhe_psk, Identity, #'ECPrivateKey'{publicKey =  ECPublicKey}}) ->
+    #client_key_exchange{
+       exchange_keys = #client_ecdhe_psk_identity{
+			  identity = Identity,
+			  dh_public = ECPublicKey}
+      };
+
 key_exchange(client, _Version, {psk_premaster_secret, PskIdentity, Secret, {_, PublicKey, _}}) ->
     EncPremasterSecret =
 	encrypted_premaster_secret(Secret, PublicKey),
@@ -275,6 +283,16 @@ key_exchange(server, Version, {dhe_psk, PskIdentityHint, {PublicKey, _},
     enc_server_key_exchange(Version, ServerEDHPSKParams,
 			    HashSign, ClientRandom, ServerRandom, PrivateKey);
 
+key_exchange(server, Version, {ecdhe_psk, PskIdentityHint,
+			       #'ECPrivateKey'{publicKey =  ECPublicKey,
+					       parameters = ECCurve},
+			       HashSign, ClientRandom, ServerRandom, PrivateKey}) ->
+    ServerECDHEPSKParams = #server_ecdhe_psk_params{
+      hint = PskIdentityHint,
+      dh_params = #server_ecdh_params{curve = ECCurve, public = ECPublicKey}},
+    enc_server_key_exchange(Version, ServerECDHEPSKParams, HashSign,
+			    ClientRandom, ServerRandom, PrivateKey);
+
 key_exchange(server, Version, {srp, {PublicKey, _},
 			       #srp_user{generator = Generator, prime = Prime,
 					 salt = Salt},
@@ -732,6 +750,7 @@ decode_server_key(ServerKey, Type, Version) ->
 			    | #client_ec_diffie_hellman_public{}
 			    | #client_psk_identity{}
 			    | #client_dhe_psk_identity{}
+			    | #client_ecdhe_psk_identity{}
 			    | #client_rsa_psk_identity{}
 			    | #client_srp_public{}.
 %%
@@ -876,9 +895,21 @@ premaster_secret(#server_dhe_psk_params{
 		    LookupFun) ->
     PremasterSecret = premaster_secret(PublicDhKey, PrivateDhKey, Params),
     psk_secret(IdentityHint, LookupFun, PremasterSecret);
+premaster_secret(#server_ecdhe_psk_params{
+		    hint = IdentityHint,
+                    dh_params = #server_ecdh_params{
+                                   public = ECServerPubKey}},
+		    PrivateEcDhKey,
+		    LookupFun) ->
+    PremasterSecret = premaster_secret(#'ECPoint'{point = ECServerPubKey}, PrivateEcDhKey),
+    psk_secret(IdentityHint, LookupFun, PremasterSecret);
 premaster_secret({rsa_psk, PSKIdentity}, PSKLookup, RSAPremasterSecret) ->
-    psk_secret(PSKIdentity, PSKLookup, RSAPremasterSecret).
-
+    psk_secret(PSKIdentity, PSKLookup, RSAPremasterSecret);
+premaster_secret(#client_ecdhe_psk_identity{
+		    identity =  PSKIdentity,
+		    dh_public = PublicEcDhPoint}, PrivateEcDhKey, PSKLookup) ->
+    PremasterSecret = premaster_secret(#'ECPoint'{point = PublicEcDhPoint}, PrivateEcDhKey),
+    psk_secret(PSKIdentity, PSKLookup, PremasterSecret).
 premaster_secret(#client_dhe_psk_identity{
 		    identity =  PSKIdentity,
 		    dh_public = PublicDhKey}, PrivateKey, #'DHParameter'{} = Params, PSKLookup) ->
@@ -1136,7 +1167,6 @@ select_hashsign_algs(undefined, ?rsaEncryption, _) ->
 select_hashsign_algs(undefined, ?'id-dsa', _) ->
     {sha, dsa}.
 
-
 srp_user(#ssl_options{srp_identity = {UserName, _}}) ->
     #srp{username = UserName};
 srp_user(_) ->
@@ -1176,7 +1206,6 @@ certificate_types(#{key_exchange := KeyExchange}, _) when KeyExchange == dh_ecds
                                                           KeyExchange == ecdh_ecdsa;
                                                           KeyExchange == ecdhe_ecdsa ->
     <<?BYTE(?ECDSA_SIGN)>>;
-
 certificate_types(_, _) ->
     <<?BYTE(?RSA_SIGN)>>.
 
@@ -1573,6 +1602,18 @@ encode_server_key(#server_dhe_psk_params{
     YLen = byte_size(Y),
     <<?UINT16(Len), PskIdentityHint/binary,
       ?UINT16(PLen), P/binary, ?UINT16(GLen), G/binary, ?UINT16(YLen), Y/binary>>;
+encode_server_key(Params = #server_ecdhe_psk_params{hint = undefined}) ->
+    encode_server_key(Params#server_ecdhe_psk_params{hint = <<>>});
+encode_server_key(#server_ecdhe_psk_params{
+		     hint = PskIdentityHint,
+		     dh_params = #server_ecdh_params{
+		       curve = {namedCurve, ECCurve}, public = ECPubKey}}) ->
+    %%TODO: support arbitrary keys
+    Len = byte_size(PskIdentityHint),
+    KLen = size(ECPubKey),
+    <<?UINT16(Len), PskIdentityHint/binary,
+      ?BYTE(?NAMED_CURVE), ?UINT16((tls_v1:oid_to_enum(ECCurve))),
+      ?BYTE(KLen), ECPubKey/binary>>;
 encode_server_key(#server_srp_params{srp_n = N, srp_g = G,	srp_s = S, srp_b = B}) ->
     NLen = byte_size(N),
     GLen = byte_size(G),
@@ -1605,6 +1646,12 @@ encode_client_key(#client_dhe_psk_identity{identity = Id, dh_public = DHPublic},
     Len = byte_size(Id),
     DHLen = byte_size(DHPublic),
     <<?UINT16(Len), Id/binary, ?UINT16(DHLen), DHPublic/binary>>;
+encode_client_key(Identity = #client_ecdhe_psk_identity{identity = undefined}, Version) ->
+    encode_client_key(Identity#client_ecdhe_psk_identity{identity = <<"psk_identity">>}, Version);
+encode_client_key(#client_ecdhe_psk_identity{identity = Id, dh_public = DHPublic}, _) ->
+    Len = byte_size(Id),
+    DHLen = byte_size(DHPublic),
+    <<?UINT16(Len), Id/binary, ?BYTE(DHLen), DHPublic/binary>>;
 encode_client_key(Identity = #client_rsa_psk_identity{identity = undefined}, Version) ->
     encode_client_key(Identity#client_rsa_psk_identity{identity = <<"psk_identity">>}, Version);
 encode_client_key(#client_rsa_psk_identity{identity = Id, exchange_keys = ExchangeKeys}, Version) ->
@@ -1725,6 +1772,22 @@ dec_server_key(<<?UINT16(Len), IdentityHint:Len/binary,
 		       params_bin = BinMsg,
 		       hashsign = HashSign,
 		       signature = Signature};
+dec_server_key(<<?UINT16(Len), IdentityHint:Len/binary,
+		 ?BYTE(?NAMED_CURVE), ?UINT16(CurveID),
+		 ?BYTE(PointLen), ECPoint:PointLen/binary,
+		 _/binary>> = KeyStruct,
+	       ?KEY_EXCHANGE_EC_DIFFIE_HELLMAN_PSK, Version) ->
+    DHParams = #server_ecdh_params{
+                  curve = {namedCurve, tls_v1:enum_to_oid(CurveID)},
+                  public = ECPoint},
+    Params = #server_ecdhe_psk_params{
+                hint = IdentityHint,
+                dh_params = DHParams},
+    {BinMsg, HashSign, Signature} = dec_server_key_params(Len + 2 + PointLen + 4, KeyStruct, Version),
+    #server_key_params{params = Params,
+		       params_bin = BinMsg,
+		       hashsign = HashSign,
+		       signature = Signature};
 dec_server_key(<<?UINT16(NLen), N:NLen/binary,
 		 ?UINT16(GLen), G:GLen/binary,
 		 ?BYTE(SLen), S:SLen/binary,
@@ -1760,6 +1823,10 @@ dec_client_key(<<?UINT16(Len), Id:Len/binary,
 		 ?UINT16(DH_YLen), DH_Y:DH_YLen/binary>>,
 	       ?KEY_EXCHANGE_DHE_PSK, _) ->
     #client_dhe_psk_identity{identity = Id, dh_public = DH_Y};
+dec_client_key(<<?UINT16(Len), Id:Len/binary,
+		 ?BYTE(DH_YLen), DH_Y:DH_YLen/binary>>,
+	       ?KEY_EXCHANGE_EC_DIFFIE_HELLMAN_PSK, _) ->
+    #client_ecdhe_psk_identity{identity = Id, dh_public = DH_Y};
 dec_client_key(<<?UINT16(Len), Id:Len/binary, PKEPMS/binary>>,
 	       ?KEY_EXCHANGE_RSA_PSK, {3, 0}) ->
     #client_rsa_psk_identity{identity = Id,
@@ -1943,6 +2010,8 @@ key_exchange_alg(psk) ->
     ?KEY_EXCHANGE_PSK;
 key_exchange_alg(dhe_psk) ->
     ?KEY_EXCHANGE_DHE_PSK;
+key_exchange_alg(ecdhe_psk) ->
+    ?KEY_EXCHANGE_EC_DIFFIE_HELLMAN_PSK;
 key_exchange_alg(rsa_psk) ->
     ?KEY_EXCHANGE_RSA_PSK;
 key_exchange_alg(Alg)
@@ -2032,7 +2101,8 @@ filter_hashsigns([Suite | Suites], [#{key_exchange := KeyExchange} | Algos], Has
       KeyExchange == ecdh_anon;
       KeyExchange == srp_anon;
       KeyExchange == psk;
-      KeyExchange == dhe_psk ->
+      KeyExchange == dhe_psk;
+      KeyExchange == ecdhe_psk ->
     %% In this case hashsigns is not used as the kexchange is anonaymous
     filter_hashsigns(Suites, Algos, HashSigns, [Suite| Acc]).
 
@@ -2171,6 +2241,7 @@ is_acceptable_hash_sign({_, ecdsa} = Algos, ecdsa, ecdsa, ecdhe_ecdsa, Supported
 is_acceptable_hash_sign(_, _, _, KeyExAlgo, _) when 
       KeyExAlgo == psk;
       KeyExAlgo == dhe_psk;
+      KeyExAlgo == ecdhe_psk;
       KeyExAlgo == srp_anon;
       KeyExAlgo == dh_anon;
       KeyExAlgo == ecdhe_anon     
@@ -2241,6 +2312,8 @@ advertises_ec_ciphers([#{key_exchange := ecdhe_rsa} | _]) ->
     true;
 advertises_ec_ciphers([#{key_exchange := ecdh_anon} | _]) ->
     true;
+advertises_ec_ciphers([{ecdhe_psk, _,_,_} | _]) ->
+    true;
 advertises_ec_ciphers([_| Rest]) ->
     advertises_ec_ciphers(Rest).
 
diff --git a/lib/ssl/src/ssl_handshake.hrl b/lib/ssl/src/ssl_handshake.hrl
index 324b7dbde3..a191fcf766 100644
--- a/lib/ssl/src/ssl_handshake.hrl
+++ b/lib/ssl/src/ssl_handshake.hrl
@@ -133,6 +133,7 @@
 -define(KEY_EXCHANGE_DIFFIE_HELLMAN, 1).
 -define(KEY_EXCHANGE_EC_DIFFIE_HELLMAN, 6).
 -define(KEY_EXCHANGE_PSK, 2).
+-define(KEY_EXCHANGE_EC_DIFFIE_HELLMAN_PSK, 7).
 -define(KEY_EXCHANGE_DHE_PSK, 3).
 -define(KEY_EXCHANGE_RSA_PSK, 4).
 -define(KEY_EXCHANGE_SRP, 5).
@@ -162,6 +163,11 @@
 	  dh_params
 	 }).
 
+-record(server_ecdhe_psk_params, {
+	  hint,
+	  dh_params
+	 }).
+
 -record(server_srp_params, {
 	  srp_n, %% opaque srp_N<1..2^16-1>
 	  srp_g, %% opaque srp_g<1..2^16-1>
@@ -254,6 +260,11 @@
 	  dh_public
 	 }).
 
+-record(client_ecdhe_psk_identity, {
+	  identity,
+	  dh_public
+	 }).
+
 -record(client_rsa_psk_identity, {
 	  identity,
 	  exchange_keys
diff --git a/lib/ssl/src/ssl_tls_dist_proxy.erl b/lib/ssl/src/ssl_tls_dist_proxy.erl
deleted file mode 100644
index 12a057fd22..0000000000
--- a/lib/ssl/src/ssl_tls_dist_proxy.erl
+++ /dev/null
@@ -1,493 +0,0 @@
-%%
-%% %CopyrightBegin%
-%%
-%% Copyright Ericsson AB 2011-2017. All Rights Reserved.
-%%
-%% Licensed under the Apache License, Version 2.0 (the "License");
-%% you may not use this file except in compliance with the License.
-%% You may obtain a copy of the License at
-%%
-%%     http://www.apache.org/licenses/LICENSE-2.0
-%%
-%% Unless required by applicable law or agreed to in writing, software
-%% distributed under the License is distributed on an "AS IS" BASIS,
-%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-%% See the License for the specific language governing permissions and
-%% limitations under the License.
-%%
-%% %CopyrightEnd%
-%%
--module(ssl_tls_dist_proxy).
-
-
--export([listen/2, accept/2, connect/4, get_tcp_address/1]).
--export([init/1, start_link/0, handle_call/3, handle_cast/2, handle_info/2, 
-	 terminate/2, code_change/3, ssl_options/2]).
-
--include_lib("kernel/include/net_address.hrl").
-
--record(state, 
-	{listen,
-	 accept_loop
-	}).
-
--define(PPRE, 4).
--define(PPOST, 4).
-
-
-%%====================================================================
-%% Internal application API
-%%====================================================================
-
-listen(Driver, Name) ->
-    gen_server:call(?MODULE, {listen, Driver, Name}, infinity).
-
-accept(Driver, Listen) ->
-    gen_server:call(?MODULE, {accept, Driver, Listen}, infinity).
-
-connect(Driver, Ip, Port, ExtraOpts) ->
-    gen_server:call(
-      ?MODULE, {connect, Driver, Ip, Port, ExtraOpts}, infinity).
-
-
-do_listen(Options) ->
-    {First,Last} = case application:get_env(kernel,inet_dist_listen_min) of
-                        {ok,N} when is_integer(N) ->
-                            case application:get_env(kernel,
-                                                    inet_dist_listen_max) of
-                               {ok,M} when is_integer(M) ->
-                                   {N,M};
-                               _ ->
-                                   {N,N}
-                            end;
-                        _ ->
-                            {0,0}
-                   end,
-    do_listen(First, Last, listen_options([{backlog,128}|Options])).
-
-do_listen(First,Last,_) when First > Last ->
-    {error,eaddrinuse};
-do_listen(First,Last,Options) ->
-    case gen_tcp:listen(First, Options) of
-        {error, eaddrinuse} ->
-            do_listen(First+1,Last,Options);
-        Other ->
-            Other
-    end.
-
-listen_options(Opts0) ->
-    Opts1 =
-        case application:get_env(kernel, inet_dist_use_interface) of
-            {ok, Ip} ->
-                [{ip, Ip} | Opts0];
-            _ ->
-                Opts0
-        end,
-    case application:get_env(kernel, inet_dist_listen_options) of
-        {ok,ListenOpts} ->
-            ListenOpts ++ Opts1;
-        _ ->
-            Opts1
-    end.
-
-connect_options(Opts) ->
-    case application:get_env(kernel, inet_dist_connect_options) of
-	{ok,ConnectOpts} ->
-	    lists:ukeysort(1, ConnectOpts ++ Opts);
-	_ ->
-	    Opts
-    end.
-
-%%====================================================================
-%% gen_server callbacks
-%%====================================================================
-
-start_link() ->
-    gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).
-
-init([]) ->
-    process_flag(priority, max),
-    {ok, #state{}}.
-
-handle_call({listen, Driver, Name}, _From, State) ->
-    case gen_tcp:listen(0, [{active, false}, {packet,?PPRE}, {ip, loopback}]) of
-	{ok, Socket} ->
-	    {ok, World} = do_listen([{active, false}, binary, {packet,?PPRE}, {reuseaddr, true},
-                                     Driver:family()]),
-	    {ok, TcpAddress} = get_tcp_address(Socket),
-	    {ok, WorldTcpAddress} = get_tcp_address(World),
-	    {_,Port} = WorldTcpAddress#net_address.address,
-	    ErlEpmd = net_kernel:epmd_module(),
-	    case ErlEpmd:register_node(Name, Port, Driver) of
-		{ok, Creation} ->
-		    {reply, {ok, {Socket, TcpAddress, Creation}},
-		     State#state{listen={Socket, World}}};
-		{error, _} = Error ->
-		    {reply, Error, State}
-	    end;
-	Error ->
-	    {reply, Error, State}
-    end;
-
-handle_call({accept, _Driver, Listen}, {From, _}, State = #state{listen={_, World}}) ->
-    Self = self(),
-    ErtsPid = spawn_link(fun() -> accept_loop(Self, erts, Listen, From) end),
-    WorldPid = spawn_link(fun() -> accept_loop(Self, world, World, Listen) end),
-    {reply, ErtsPid, State#state{accept_loop={ErtsPid, WorldPid}}};
-
-handle_call({connect, Driver, Ip, Port, ExtraOpts}, {From, _}, State) ->
-    Me = self(),
-    Pid =
-        spawn_link(
-          fun() -> setup_proxy(Driver, Ip, Port, ExtraOpts, Me) end),
-    receive 
-	{Pid, go_ahead, LPort} -> 
-	    Res = {ok, Socket} = try_connect(LPort),
-	    case gen_tcp:controlling_process(Socket, From) of
-		{error, badarg} = Error -> {reply, Error, State};   % From is dead anyway.
-		ok ->
-		    flush_old_controller(From, Socket),
-		    {reply, Res, State}
-	    end;
-	{Pid, Error} ->
-	    {reply, Error, State}
-    end;
-
-handle_call(_What, _From, State) ->
-    {reply, ok, State}.
-
-handle_cast(_What, State) ->
-    {noreply, State}.
-
-handle_info(_What, State) ->
-    {noreply, State}.
-
-terminate(_Reason, _St) ->
-    ok.
-
-code_change(_OldVsn, St, _Extra) ->
-    {ok, St}.
-
-%%--------------------------------------------------------------------
-%%% Internal functions
-%%--------------------------------------------------------------------
-get_tcp_address(Socket) ->
-    case inet:sockname(Socket) of
-	{ok, Address} ->
-	    {ok, Host} = inet:gethostname(),
-	    NetAddress = #net_address{
-			    address = Address,
-			    host = Host,
-			    protocol = proxy,
-			    family = inet
-			   },
-	    {ok, NetAddress};
-	{error, _} = Error -> Error
-    end.
-
-accept_loop(Proxy, erts = Type, Listen, Extra) ->
-    process_flag(priority, max),
-    case gen_tcp:accept(Listen) of
-	{ok, Socket} ->
-	    Extra ! {accept,self(),Socket,inet,proxy},
-	    receive 
-		{_Kernel, controller, Pid} ->
-		    inet:setopts(Socket, [nodelay()]),
-		    ok = gen_tcp:controlling_process(Socket, Pid),
-		    flush_old_controller(Pid, Socket),
-		    Pid ! {self(), controller};
-		{_Kernel, unsupported_protocol} ->
-		    exit(unsupported_protocol)
-	    end;
-	{error, closed} ->
-	    %% The listening socket is closed: the proxy process is
-	    %% shutting down.  Exit normally, to avoid generating a
-	    %% spurious error report.
-	    exit(normal);
-	Error ->
-	    exit(Error)
-    end,
-    accept_loop(Proxy, Type, Listen, Extra);
-
-accept_loop(Proxy, world = Type, Listen, Extra) ->
-    process_flag(priority, max),
-    case gen_tcp:accept(Listen) of
-	{ok, Socket} ->
-	    Opts = get_ssl_options(server),
-	    wait_for_code_server(),
-	    case ssl:ssl_accept(Socket, Opts) of
-		{ok, SslSocket} ->
-		    PairHandler =
-			spawn_link(fun() ->
-					   setup_connection(SslSocket, Extra)
-				   end),
-		    ok = ssl:controlling_process(SslSocket, PairHandler),
-		    flush_old_controller(PairHandler, SslSocket);
-		{error, {options, _}} = Error ->
-		    %% Bad options: that's probably our fault.  Let's log that.
-		    error_logger:error_msg("Cannot accept TLS distribution connection: ~s~n",
-					   [ssl:format_error(Error)]),
-		    gen_tcp:close(Socket);
-		_ ->
-		    gen_tcp:close(Socket)
-	    end;
-	Error ->
-	    exit(Error)
-    end,
-    accept_loop(Proxy, Type, Listen, Extra).
-
-wait_for_code_server() ->
-    %% This is an ugly hack.  Upgrading a socket to TLS requires the
-    %% crypto module to be loaded.  Loading the crypto module triggers
-    %% its on_load function, which calls code:priv_dir/1 to find the
-    %% directory where its NIF library is.  However, distribution is
-    %% started earlier than the code server, so the code server is not
-    %% necessarily started yet, and code:priv_dir/1 might fail because
-    %% of that, if we receive an incoming connection on the
-    %% distribution port early enough.
-    %%
-    %% If the on_load function of a module fails, the module is
-    %% unloaded, and the function call that triggered loading it fails
-    %% with 'undef', which is rather confusing.
-    %%
-    %% Thus, the ssl_tls_dist_proxy process will terminate, and be
-    %% restarted by ssl_dist_sup.  However, it won't have any memory
-    %% of being asked by net_kernel to listen for incoming
-    %% connections.  Hence, the node will believe that it's open for
-    %% distribution, but it actually isn't.
-    %%
-    %% So let's avoid that by waiting for the code server to start.
-    case whereis(code_server) of
-	undefined ->
-	    timer:sleep(10),
-	    wait_for_code_server();
-	Pid when is_pid(Pid) ->
-	    ok
-    end.
-
-try_connect(Port) ->
-    case gen_tcp:connect({127,0,0,1}, Port, [{active, false}, {packet,?PPRE}, nodelay()]) of
-	R = {ok, _S} ->
-	    R;
-	{error, _R} ->
-	    try_connect(Port)
-    end.
-
-setup_proxy(Driver, Ip, Port, ExtraOpts, Parent) ->
-    process_flag(trap_exit, true),
-    Opts = connect_options(ExtraOpts ++ get_ssl_options(client)),
-    case ssl:connect(Ip, Port, [{active, true}, binary, {packet,?PPRE}, nodelay(),
-                                Driver:family()] ++ Opts) of
-	{ok, World} ->
-	    {ok, ErtsL} = gen_tcp:listen(0, [{active, true}, {ip, loopback}, binary, {packet,?PPRE}]),
-	    {ok, #net_address{address={_,LPort}}} = get_tcp_address(ErtsL),
-	    Parent ! {self(), go_ahead, LPort},
-	    case gen_tcp:accept(ErtsL) of
-		{ok, Erts} ->
-		    %% gen_tcp:close(ErtsL),
-		    loop_conn_setup(World, Erts);
-		Err ->
-		    Parent ! {self(), Err}
-	    end;
-	{error, {options, _}} = Err ->
-	    %% Bad options: that's probably our fault.  Let's log that.
-	    error_logger:error_msg("Cannot open TLS distribution connection: ~s~n",
-				   [ssl:format_error(Err)]),
-	    Parent ! {self(), Err};
-	Err ->
-	    Parent ! {self(), Err}
-    end.
-
-
-%% we may not always want the nodelay behaviour
-%% %% for performance reasons
-
-nodelay() ->
-    case application:get_env(kernel, dist_nodelay) of
-  undefined ->
-      {nodelay, true};
-  {ok, true} ->
-      {nodelay, true};
-  {ok, false} ->
-      {nodelay, false};
-  _ ->
-      {nodelay, true}
-    end.
-
-setup_connection(World, ErtsListen) ->
-    process_flag(trap_exit, true),
-    {ok, TcpAddress} = get_tcp_address(ErtsListen),
-    {_Addr,Port} = TcpAddress#net_address.address,
-    {ok, Erts} = gen_tcp:connect({127,0,0,1}, Port, [{active, true}, binary, {packet,?PPRE}, nodelay()]),
-    ssl:setopts(World, [{active,true}, {packet,?PPRE}, nodelay()]),
-    loop_conn_setup(World, Erts).
-
-loop_conn_setup(World, Erts) ->
-    receive 
-	{ssl, World, Data = <<$a, _/binary>>} ->
-	    gen_tcp:send(Erts, Data),
-	    ssl:setopts(World, [{packet,?PPOST}, nodelay()]),
-	    inet:setopts(Erts, [{packet,?PPOST}, nodelay()]),
-	    loop_conn(World, Erts);
-	{tcp, Erts, Data = <<$a, _/binary>>} ->
-	    ssl:send(World, Data),
-	    ssl:setopts(World, [{packet,?PPOST}, nodelay()]),
-	    inet:setopts(Erts, [{packet,?PPOST}, nodelay()]),
-	    loop_conn(World, Erts);
-	{ssl, World, Data = <<_, _/binary>>} ->
-	    gen_tcp:send(Erts, Data),
-	    loop_conn_setup(World, Erts);
-	{tcp, Erts, Data = <<_, _/binary>>} ->
-	    ssl:send(World, Data),
-	    loop_conn_setup(World, Erts);
-	{ssl, World, Data} ->
-	    gen_tcp:send(Erts, Data),
-	    loop_conn_setup(World, Erts);
-	{tcp, Erts, Data} ->
-	    ssl:send(World, Data),
-	    loop_conn_setup(World, Erts);
-	{tcp_closed, Erts} ->
-	    ssl:close(World);
-	{ssl_closed,  World} ->
-	    gen_tcp:close(Erts);
-	{ssl_error, World, _} ->
-
-	    ssl:close(World)
-    end.
-
-loop_conn(World, Erts) ->
-    receive 
-	{ssl, World, Data} ->
-	    gen_tcp:send(Erts, Data),
-	    loop_conn(World, Erts);
-	{tcp, Erts, Data} ->
-	    ssl:send(World, Data),
-	    loop_conn(World, Erts);
-	{tcp_closed, Erts} ->
-	    ssl:close(World);
-	{ssl_closed,  World} ->
-	    gen_tcp:close(Erts);
-	{ssl_error, World, _} ->
-	    ssl:close(World)
-    end.
-
-get_ssl_options(Type) ->
-    try ets:lookup(ssl_dist_opts, Type) of
-        [{Type, Opts}] ->
-            [{erl_dist, true} | Opts];
-        _ ->
-            get_ssl_dist_arguments(Type)
-    catch
-        error:badarg ->
-            get_ssl_dist_arguments(Type)
-    end.
-
-get_ssl_dist_arguments(Type) ->
-    case init:get_argument(ssl_dist_opt) of
-	{ok, Args} ->
-	    [{erl_dist, true} | ssl_options(Type, lists:append(Args))];
-	_ ->
-	    [{erl_dist, true}]
-    end.
-
-ssl_options(_,[]) ->
-    [];
-ssl_options(server, ["client_" ++ _, _Value |T]) ->
-    ssl_options(server,T);
-ssl_options(client, ["server_" ++ _, _Value|T]) ->
-    ssl_options(client,T);
-ssl_options(server, ["server_certfile", Value|T]) ->
-    [{certfile, Value} | ssl_options(server,T)];
-ssl_options(client, ["client_certfile", Value | T]) ->
-    [{certfile, Value} | ssl_options(client,T)];
-ssl_options(server, ["server_cacertfile", Value|T]) ->
-    [{cacertfile, Value} | ssl_options(server,T)];
-ssl_options(client, ["client_cacertfile", Value|T]) ->
-    [{cacertfile, Value} | ssl_options(client,T)];
-ssl_options(server, ["server_keyfile", Value|T]) ->
-    [{keyfile, Value} | ssl_options(server,T)];
-ssl_options(client, ["client_keyfile", Value|T]) ->
-    [{keyfile, Value} | ssl_options(client,T)];
-ssl_options(server, ["server_password", Value|T]) ->
-    [{password, Value} | ssl_options(server,T)];
-ssl_options(client, ["client_password", Value|T]) ->
-    [{password, Value} | ssl_options(client,T)];
-ssl_options(server, ["server_verify", Value|T]) ->
-    [{verify, atomize(Value)} | ssl_options(server,T)];
-ssl_options(client, ["client_verify", Value|T]) ->
-    [{verify, atomize(Value)} | ssl_options(client,T)];
-ssl_options(server, ["server_verify_fun", Value|T]) ->
-    [{verify_fun, verify_fun(Value)} | ssl_options(server,T)];
-ssl_options(client, ["client_verify_fun", Value|T]) ->
-    [{verify_fun, verify_fun(Value)} | ssl_options(client,T)];
-ssl_options(server, ["server_crl_check", Value|T]) ->
-    [{crl_check, atomize(Value)} | ssl_options(server,T)];
-ssl_options(client, ["client_crl_check", Value|T]) ->
-    [{crl_check, atomize(Value)} | ssl_options(client,T)];
-ssl_options(server, ["server_crl_cache", Value|T]) ->
-    [{crl_cache, termify(Value)} | ssl_options(server,T)];
-ssl_options(client, ["client_crl_cache", Value|T]) ->
-    [{crl_cache, termify(Value)} | ssl_options(client,T)];
-ssl_options(server, ["server_reuse_sessions", Value|T]) ->
-    [{reuse_sessions, atomize(Value)} | ssl_options(server,T)];
-ssl_options(client, ["client_reuse_sessions", Value|T]) ->
-    [{reuse_sessions, atomize(Value)} | ssl_options(client,T)];
-ssl_options(server, ["server_secure_renegotiate", Value|T]) ->
-    [{secure_renegotiate, atomize(Value)} | ssl_options(server,T)];
-ssl_options(client, ["client_secure_renegotiate", Value|T]) ->
-    [{secure_renegotiate, atomize(Value)} | ssl_options(client,T)];
-ssl_options(server, ["server_depth", Value|T]) ->
-    [{depth, list_to_integer(Value)} | ssl_options(server,T)];
-ssl_options(client, ["client_depth", Value|T]) ->
-    [{depth, list_to_integer(Value)} | ssl_options(client,T)];
-ssl_options(server, ["server_hibernate_after", Value|T]) ->
-    [{hibernate_after, list_to_integer(Value)} | ssl_options(server,T)];
-ssl_options(client, ["client_hibernate_after", Value|T]) ->
-    [{hibernate_after, list_to_integer(Value)} | ssl_options(client,T)];
-ssl_options(server, ["server_ciphers", Value|T]) ->
-    [{ciphers, Value} | ssl_options(server,T)];
-ssl_options(client, ["client_ciphers", Value|T]) ->
-    [{ciphers, Value} | ssl_options(client,T)];
-ssl_options(server, ["server_dhfile", Value|T]) ->
-    [{dhfile, Value} | ssl_options(server,T)];
-ssl_options(server, ["server_fail_if_no_peer_cert", Value|T]) ->
-    [{fail_if_no_peer_cert, atomize(Value)} | ssl_options(server,T)];
-ssl_options(Type, Opts) ->
-    error(malformed_ssl_dist_opt, [Type, Opts]).
-
-atomize(List) when is_list(List) ->
-    list_to_atom(List);
-atomize(Atom) when is_atom(Atom) ->
-    Atom.
-
-termify(String) when is_list(String) ->
-    {ok, Tokens, _} = erl_scan:string(String ++ "."),
-    {ok, Term} = erl_parse:parse_term(Tokens),
-    Term.
-
-verify_fun(Value) ->
-    case termify(Value) of
-	{Mod, Func, State} when is_atom(Mod), is_atom(Func) ->
-	    Fun = fun Mod:Func/3,
-	    {Fun, State};
-	_ ->
-	    error(malformed_ssl_dist_opt, [Value])
-    end.
-
-flush_old_controller(Pid, Socket) ->
-    receive
-	{tcp, Socket, Data} ->
-	    Pid ! {tcp, Socket, Data},
-	    flush_old_controller(Pid, Socket);
-	{tcp_closed, Socket} ->
-	    Pid ! {tcp_closed, Socket},
-	    flush_old_controller(Pid, Socket);
-	{ssl, Socket, Data} ->
-	    Pid ! {ssl, Socket, Data},
-	    flush_old_controller(Pid, Socket);
-	{ssl_closed, Socket} ->
-	    Pid ! {ssl_closed, Socket},
-	    flush_old_controller(Pid, Socket)
-    after 0 ->
-	    ok
-    end.
diff --git a/lib/ssl/src/tls_connection.erl b/lib/ssl/src/tls_connection.erl
index b033eea261..406a095d2e 100644
--- a/lib/ssl/src/tls_connection.erl
+++ b/lib/ssl/src/tls_connection.erl
@@ -63,7 +63,7 @@
 %% gen_statem state functions
 -export([init/3, error/3, downgrade/3, %% Initiation and take down states
 	 hello/3, certify/3, cipher/3, abbreviated/3, %% Handshake states 
-	 connection/3]). 
+	 connection/3, death_row/3]).
 %% gen_statem callbacks
 -export([callback_mode/0, terminate/3, code_change/4, format_status/2]).
  
@@ -437,7 +437,8 @@ init(Type, Event, State) ->
 %%--------------------------------------------------------------------
 
 error({call, From}, {start, _Timeout}, {Error, State}) ->
-    {stop_and_reply, normal, {reply, From, {error, Error}}, State};
+    ssl_connection:stop_and_reply(
+      normal, {reply, From, {error, Error}}, State);
 error({call, _} = Call, Msg, State) ->
     gen_handshake(?FUNCTION_NAME, Call, Msg, State);
 error(_, _, _) ->
@@ -565,6 +566,13 @@ connection(Type, Event, State) ->
     ssl_connection:?FUNCTION_NAME(Type, Event, State, ?MODULE).
 
 %%--------------------------------------------------------------------
+-spec death_row(gen_statem:event_type(), term(), #state{}) ->
+		       gen_statem:state_function_result().
+%%--------------------------------------------------------------------
+death_row(Type, Event, State) ->
+     ssl_connection:death_row(Type, Event, State, ?MODULE).
+
+%%--------------------------------------------------------------------
 -spec downgrade(gen_statem:event_type(), term(), #state{}) ->
 		       gen_statem:state_function_result().
 %%--------------------------------------------------------------------
@@ -652,7 +660,7 @@ handle_info({Protocol, _, Data}, StateName,
 	    next_event(StateName, Record, State);
 	#alert{} = Alert ->
 	    ssl_connection:handle_normal_shutdown(Alert, StateName, State0), 
-	    {stop, {shutdown, own_alert}}
+	    ssl_connection:stop({shutdown, own_alert}, State0)
     end;
 handle_info({CloseTag, Socket}, StateName,
             #state{socket = Socket, close_tag = CloseTag,
@@ -679,7 +687,7 @@ handle_info({CloseTag, Socket}, StateName,
             end,
 
             ssl_connection:handle_normal_shutdown(?ALERT_REC(?FATAL, ?CLOSE_NOTIFY), StateName, State),
-            {stop, {shutdown, transport_closed}};
+            ssl_connection:stop({shutdown, transport_closed}, State);
         true ->
             %% Fixes non-delivery of final TLS record in {active, once}.
             %% Basically allows the application the opportunity to set {active, once} again
@@ -691,7 +699,7 @@ handle_info(Msg, StateName, State) ->
 
 handle_alerts([], Result) ->
     Result;
-handle_alerts(_, {stop,_} = Stop) ->
+handle_alerts(_, {stop, _, _} = Stop) ->
     Stop;
 handle_alerts([Alert | Alerts], {next_state, StateName, State}) ->
      handle_alerts(Alerts, ssl_connection:handle_alert(Alert, StateName, State));
diff --git a/lib/ssl/test/Makefile b/lib/ssl/test/Makefile
index aa01552c39..9347b56f39 100644
--- a/lib/ssl/test/Makefile
+++ b/lib/ssl/test/Makefile
@@ -37,6 +37,8 @@ VSN=$(GS_VSN)
 
 MODULES = \
 	ssl_test_lib \
+	ssl_bench_test_lib \
+	ssl_dist_test_lib \
 	ssl_alpn_handshake_SUITE \
 	ssl_basic_SUITE \
 	ssl_bench_SUITE \
@@ -44,6 +46,7 @@ MODULES = \
 	ssl_certificate_verify_SUITE\
 	ssl_crl_SUITE\
 	ssl_dist_SUITE \
+	ssl_dist_bench_SUITE \
 	ssl_engine_SUITE\
 	ssl_handshake_SUITE \
 	ssl_npn_hello_SUITE \
@@ -62,7 +65,8 @@ MODULES = \
 
 ERL_FILES = $(MODULES:%=%.erl)
 
-HRL_FILES =
+HRL_FILES = \
+	ssl_dist_test_lib.hrl
 
 HRL_FILES_SRC = \
 	ssl_api.hrl\
diff --git a/lib/ssl/test/ssl.spec b/lib/ssl/test/ssl.spec
index 0ad94e22bc..17b66aef40 100644
--- a/lib/ssl/test/ssl.spec
+++ b/lib/ssl/test/ssl.spec
@@ -3,3 +3,6 @@
     ssl_bench_SUITE, [setup_sequential, setup_concurrent, payload_simple,
 	use_pem_cache, bypass_pem_cache],
     "Benchmarks run separately"}.
+{skip_suites, "../ssl_test",
+     [ssl_dist_bench_SUITE],
+     "Benchmarks run separately"}.
diff --git a/lib/ssl/test/ssl_bench.spec b/lib/ssl/test/ssl_bench.spec
index d2f75b4203..8b746c5ca9 100644
--- a/lib/ssl/test/ssl_bench.spec
+++ b/lib/ssl/test/ssl_bench.spec
@@ -1 +1 @@
-{suites,"../ssl_test",[ssl_bench_SUITE]}.
+{suites,"../ssl_test",[ssl_bench_SUITE, ssl_dist_bench_SUITE]}.
diff --git a/lib/ssl/test/ssl_bench_SUITE.erl b/lib/ssl/test/ssl_bench_SUITE.erl
index ae2928b1c3..3fe6338d69 100644
--- a/lib/ssl/test/ssl_bench_SUITE.erl
+++ b/lib/ssl/test/ssl_bench_SUITE.erl
@@ -40,11 +40,11 @@ end_per_group(_GroupName, _Config) ->
     ok.
 
 init_per_suite(Config) ->
-    try
-	Server = setup(ssl, node()),
-	[{server_node, Server}|Config]
-    catch _:_ ->
-	    {skipped, "Benchmark machines only"}
+    case node() of
+        nonode@nohost ->
+            {skipped, "Node not distributed"};
+        _ ->
+            [{server_node, ssl_bench_test_lib:setup(perf_server)}|Config]
     end.
 
 end_per_suite(_Config) ->
@@ -132,10 +132,10 @@ bypass_pem_cache(_Config) ->
 
 
 ssl() ->
-    test(ssl, ?COUNT, node()).
+    test(ssl, ?COUNT).
 
-test(Type, Count, Host) ->
-    Server = setup(Type, Host),
+test(Type, Count) ->
+    Server = ssl_bench_test_lib:setup(perf_server),
     (do_test(Type, setup_connection, Count * 20, 1, Server)),
     (do_test(Type, setup_connection, Count, 100, Server)),
     (do_test(Type, payload, Count*300, 10, Server)),
@@ -294,47 +294,6 @@ msg() ->
       "asdlkjsafsdfoierwlejsdlkfjsdf">>.
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-setup(_Type, nonode@nohost) ->
-    exit(dist_not_enabled);
-setup(Type, _This) ->
-    Host = case os:getenv(?remote_host) of
-	       false ->
-		   {ok, This} = inet:gethostname(),
-		   This;
-	       RemHost ->
-		   RemHost
-	   end,
-    Node = list_to_atom("perf_server@" ++ Host),
-    SlaveArgs = case init:get_argument(pa) of
-	       {ok, PaPaths} ->
-		   lists:append([" -pa " ++ P || [P] <- PaPaths]);
-	       _ -> []
-	   end,
-    %% io:format("Slave args: ~p~n",[SlaveArgs]),
-    Prog =
-	case os:find_executable("erl") of
-	    false -> "erl";
-	    P -> P
-	end,
-    io:format("Prog = ~p~n", [Prog]),
-
-    case net_adm:ping(Node) of
-	pong -> ok;
-	pang ->
-	    {ok, Node} = slave:start(Host, perf_server, SlaveArgs, no_link, Prog)
-    end,
-    Path = code:get_path(),
-    true = rpc:call(Node, code, set_path, [Path]),
-    ok = rpc:call(Node, ?MODULE, setup_server, [Type, node()]),
-    io:format("Client (~p) using ~s~n",[node(), code:which(ssl)]),
-    (Node =:= node()) andalso restrict_schedulers(client),
-    Node.
-
-setup_server(_Type, ClientNode) ->
-    (ClientNode =:= node()) andalso restrict_schedulers(server),
-    io:format("Server (~p) using ~s~n",[node(), code:which(ssl)]),
-    ok.
-
 
 ensure_all_started(App, Ack) ->
     case application:start(App) of
@@ -358,13 +317,6 @@ setup_server_init(Type, Tc, Loop, PC) ->
     unlink(Pid),
     Res.
 
-restrict_schedulers(Type) ->
-    %% We expect this to run on 8 core machine
-    Extra0 = 1,
-    Extra =  if (Type =:= server) -> -Extra0; true -> Extra0 end,
-    Scheds = erlang:system_info(schedulers),
-    erlang:system_flag(schedulers_online, (Scheds div 2) + Extra).
-
 tc(Fun, Mod, Line) ->
     case timer:tc(Fun) of
 	{_,{'EXIT',Reason}} ->
diff --git a/lib/ssl/test/ssl_bench_test_lib.erl b/lib/ssl/test/ssl_bench_test_lib.erl
new file mode 100644
index 0000000000..e5cbb911bd
--- /dev/null
+++ b/lib/ssl/test/ssl_bench_test_lib.erl
@@ -0,0 +1,75 @@
+%%%-------------------------------------------------------------------
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(ssl_bench_test_lib).
+
+%% API
+-export([setup/1]).
+
+%% Internal exports
+-export([setup_server/1]).
+
+-define(remote_host, "NETMARKS_REMOTE_HOST").
+
+setup(Name) ->
+    Host = case os:getenv(?remote_host) of
+	       false ->
+		   {ok, This} = inet:gethostname(),
+		   This;
+	       RemHost ->
+		   RemHost
+	   end,
+    Node = list_to_atom(atom_to_list(Name) ++ "@" ++ Host),
+    SlaveArgs = case init:get_argument(pa) of
+	       {ok, PaPaths} ->
+		   lists:append([" -pa " ++ P || [P] <- PaPaths]);
+	       _ -> []
+	   end,
+    %% io:format("Slave args: ~p~n",[SlaveArgs]),
+    Prog =
+	case os:find_executable("erl") of
+	    false -> "erl";
+	    P -> P
+	end,
+    io:format("Prog = ~p~n", [Prog]),
+
+    case net_adm:ping(Node) of
+	pong -> ok;
+	pang ->
+	    {ok, Node} =
+                slave:start(Host, Name, SlaveArgs, no_link, Prog)
+    end,
+    Path = code:get_path(),
+    true = rpc:call(Node, code, set_path, [Path]),
+    ok = rpc:call(Node, ?MODULE, setup_server, [node()]),
+    io:format("Client (~p) using ~s~n",[node(), code:which(ssl)]),
+    (Node =:= node()) andalso restrict_schedulers(client),
+    Node.
+
+setup_server(ClientNode) ->
+    (ClientNode =:= node()) andalso restrict_schedulers(server),
+    io:format("Server (~p) using ~s~n",[node(), code:which(ssl)]),
+    ok.
+
+restrict_schedulers(Type) ->
+    %% We expect this to run on 8 core machine
+    Extra0 = 1,
+    Extra =  if (Type =:= server) -> -Extra0; true -> Extra0 end,
+    Scheds = erlang:system_info(schedulers),
+    erlang:system_flag(schedulers_online, (Scheds div 2) + Extra).
diff --git a/lib/ssl/test/ssl_dist_SUITE.erl b/lib/ssl/test/ssl_dist_SUITE.erl
index 8740e8c8f0..c822a52d1f 100644
--- a/lib/ssl/test/ssl_dist_SUITE.erl
+++ b/lib/ssl/test/ssl_dist_SUITE.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2007-2016. All Rights Reserved.
+%% Copyright Ericsson AB 2007-2017. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -22,6 +22,7 @@
 
 -include_lib("common_test/include/ct.hrl").
 -include_lib("public_key/include/public_key.hrl").
+-include("ssl_dist_test_lib.hrl").
 
 %% Note: This directive should only be used in test suites.
 -compile(export_all).
@@ -30,12 +31,12 @@
 
 -define(AWAIT_SSL_NODE_UP_TIMEOUT, 30000).
 
--record(node_handle,
-	{connection_handler,
-	 socket,
-	 name,
-	 nodename}
-       ).
+-import(ssl_dist_test_lib,
+        [tstsrvr_format/2, send_to_tstcntrl/1,
+         apply_on_ssl_node/4, apply_on_ssl_node/2,
+         stop_ssl_node/1]).
+start_ssl_node_name(Name, Args) ->
+    ssl_dist_test_lib:start_ssl_node(Name, Args).
 
 %%--------------------------------------------------------------------
 %% Common Test interface functions -----------------------------------
@@ -140,11 +141,14 @@ basic_test(NH1, NH2, _) ->
 		  apply_on_ssl_node(
 		    NH1,
 		    fun () ->
-			    tstsrvr_format("Hi from ~p!~n", [node()]),
-			    send_to_tstcntrl({Ref, self()}),
+			    tstsrvr_format(
+                              "Hi from ~p!~n", [node()]),
+			    send_to_tstcntrl(
+                              {Ref, self()}),
 			    receive
 				{From, ping} ->
-				    tstsrvr_format("Received ping ~p!~n", [node()]),
+				    tstsrvr_format(
+                                      "Received ping ~p!~n", [node()]),
 				    From ! {self(), pong}
 			    end
 		    end)
@@ -154,7 +158,8 @@ basic_test(NH1, NH2, _) ->
 	     ok = apply_on_ssl_node(
 		    NH2,
 		    fun () ->
-			    tstsrvr_format("Hi from ~p!~n", [node()]),
+			    tstsrvr_format(
+                              "Hi from ~p!~n", [node()]),
 			    SslPid ! {self(), ping},
 			    receive
 				{SslPid, pong} ->
@@ -183,7 +188,8 @@ payload_test(NH1, NH2, _) ->
 		  apply_on_ssl_node(
 		    NH1,
 		    fun () ->
-			    send_to_tstcntrl({Ref, self()}),
+			    send_to_tstcntrl(
+                              {Ref, self()}),
 			    receive
 				{From, Msg} ->
 				    From ! {self(), Msg}
@@ -616,12 +622,6 @@ gen_dist_test(Test, Config) ->
 %% ssl_node side api
 %%
 
-tstsrvr_format(Fmt, ArgList) ->
-    send_to_tstsrvr({format, Fmt, ArgList}).
-
-send_to_tstcntrl(Message) ->
-    send_to_tstsrvr({message, Message}).
-
 try_setting_priority(TestFun, Config) ->
     Prio = 1,
     case gen_udp:open(0, [{priority,Prio}]) of
@@ -653,44 +653,6 @@ inet_ports() ->
 %% test_server side api
 %%
 
-apply_on_ssl_node(Node, M, F, A) when is_atom(M), is_atom(F), is_list(A) ->
-    Ref = make_ref(),
-    send_to_ssl_node(Node, {apply, self(), Ref, M, F, A}),
-    receive
-	{Ref, Result} ->
-	    Result
-    end.
-
-apply_on_ssl_node(Node, Fun) when is_function(Fun, 0) ->
-    Ref = make_ref(),
-    send_to_ssl_node(Node, {apply, self(), Ref, Fun}),
-    receive
-	{Ref, Result} ->
-	    Result
-    end.
-
-stop_ssl_node(#node_handle{connection_handler = Handler,
-			   socket = Socket,
-			   name = Name}) ->
-    ?t:format("Trying to stop ssl node ~s.~n", [Name]),
-    Mon = erlang:monitor(process, Handler),
-    unlink(Handler),
-    case gen_tcp:send(Socket, term_to_binary(stop)) of
-	ok ->
-	    receive
-		{'DOWN', Mon, process, Handler, Reason} ->
-		    case Reason of
-			normal ->
-			    ok;
-			_ -> 
-			    ct:pal("Down  ~p ~n", [Reason])
-		    end
-	    end;
-	Error ->
-	    erlang:demonitor(Mon, [flush]),
-	    ct:pal("Warning  ~p ~n", [Error])
-    end.
-
 start_ssl_node(Config) ->
     start_ssl_node(Config, "").
 
@@ -698,29 +660,8 @@ start_ssl_node(Config, XArgs) ->
     Name = mk_node_name(Config),
     SSL = proplists:get_value(ssl_opts, Config),
     SSLDistOpts = setup_dist_opts(Config),
-    start_ssl_node_raw(Name, SSL ++ " " ++ SSLDistOpts ++ XArgs).
-
-start_ssl_node_raw(Name, Args) ->
-    {ok, LSock} = gen_tcp:listen(0,
-				 [binary, {packet, 4}, {active, false}]),
-    {ok, ListenPort} = inet:port(LSock),
-    CmdLine = mk_node_cmdline(ListenPort, Name, Args),
-    ?t:format("Attempting to start ssl node ~ts: ~ts~n", [Name, CmdLine]),
-    case open_port({spawn, CmdLine}, []) of
-	Port when is_port(Port) ->
-	    unlink(Port),
-	    erlang:port_close(Port),
-	    case await_ssl_node_up(Name, LSock) of
-		#node_handle{} = NodeHandle ->
-		    ?t:format("Ssl node ~s started.~n", [Name]),
-		    NodeName = list_to_atom(Name ++ "@" ++ host_name()),
-		    NodeHandle#node_handle{nodename = NodeName};
-		Error ->
-		    exit({failed_to_start_node, Name, Error})
-	    end;
-	Error ->
-	    exit({failed_to_start_node, Name, Error})
-    end.
+    start_ssl_node_name(
+      Name, SSL ++ " " ++ SSLDistOpts ++ XArgs).
 
 cache_crls_on_ssl_nodes(PrivDir, CANames, NHs) ->
     [begin
@@ -739,11 +680,6 @@ cache_crls_on_ssl_nodes(PrivDir, CANames, NHs) ->
 %% command line creation
 %%
 
-host_name() ->
-    [$@ | Host] = lists:dropwhile(fun ($@) -> false; (_) -> true end,
-				  atom_to_list(node())),
-    Host.
-
 mk_node_name(Config) ->
     N = erlang:unique_integer([positive]),
     Case = proplists:get_value(testcase, Config),
@@ -753,225 +689,6 @@ mk_node_name(Config) ->
 	++ "_"
 	++ integer_to_list(N).
 
-mk_node_cmdline(ListenPort, Name, Args) ->
-    Static = "-detached -noinput",
-    Pa = filename:dirname(code:which(?MODULE)),
-    Prog = case catch init:get_argument(progname) of
-	       {ok,[[P]]} -> P;
-	       _ -> exit(no_progname_argument_found)
-	   end,
-    NameSw = case net_kernel:longnames() of
-		 false -> "-sname ";
-		 _ -> "-name "
-	     end,
-    {ok, Pwd} = file:get_cwd(),
-    "\"" ++ Prog ++ "\" "
-	++ Static ++ " "
-	++ NameSw ++ " " ++ Name ++ " "
-	++ "-pa " ++ Pa ++ " "
-	++ "-run application start crypto -run application start public_key "
-	++ "-eval 'net_kernel:verbose(1)' "
-	++ "-run " ++ atom_to_list(?MODULE) ++ " cnct2tstsrvr "
-	++ host_name() ++ " "
-	++ integer_to_list(ListenPort) ++ " "
-	++ Args ++ " "
-	++ "-env ERL_CRASH_DUMP " ++ Pwd ++ "/erl_crash_dump." ++ Name ++ " "
-	++ "-kernel error_logger \"{file,\\\"" ++ Pwd ++ "/error_log." ++ Name ++ "\\\"}\" "
-	++ "-setcookie " ++ atom_to_list(erlang:get_cookie()).
-
-%%
-%% Connection handler test_server side
-%%
-
-await_ssl_node_up(Name, LSock) ->
-    case gen_tcp:accept(LSock, ?AWAIT_SSL_NODE_UP_TIMEOUT) of
-	timeout ->
-	    gen_tcp:close(LSock),
-	    ?t:format("Timeout waiting for ssl node ~s to come up~n",
-		      [Name]),
-	    timeout;
-	{ok, Socket} ->
-	    gen_tcp:close(LSock),
-	    case gen_tcp:recv(Socket, 0) of
-		{ok, Bin} ->
-		    check_ssl_node_up(Socket, Name, Bin);
-		{error, closed} ->
-		    gen_tcp:close(Socket),
-		    exit({lost_connection_with_ssl_node_before_up, Name})
-	    end;
-	{error, Error} ->
-	    gen_tcp:close(LSock),
-	    exit({accept_failed, Error})
-    end.
-
-check_ssl_node_up(Socket, Name, Bin) ->
-    case catch binary_to_term(Bin) of
-	{'EXIT', _} ->
-	    gen_tcp:close(Socket),
-	    exit({bad_data_received_from_ssl_node, Name, Bin});
-	{ssl_node_up, NodeName} ->
-	    case list_to_atom(Name++"@"++host_name()) of
-		NodeName ->
-		    Parent = self(),
-		    Go = make_ref(),
-		    %% Spawn connection handler on test server side
-		    Pid = spawn_link(
-			    fun () ->
-				    receive Go -> ok end,
-				    tstsrvr_con_loop(Name, Socket, Parent)
-			    end),
-		    ok = gen_tcp:controlling_process(Socket, Pid),
-		    Pid ! Go,
-		    #node_handle{connection_handler = Pid,
-				 socket = Socket,
-				 name = Name};
-		_ ->
-		    exit({unexpected_ssl_node_connected, NodeName})
-	    end;
-	Msg ->
-	    exit({unexpected_msg_instead_of_ssl_node_up, Name, Msg})
-    end.
-
-send_to_ssl_node(#node_handle{connection_handler = Hndlr}, Term) ->
-    Hndlr ! {relay_to_ssl_node, term_to_binary(Term)},
-    ok.
-
-tstsrvr_con_loop(Name, Socket, Parent) ->
-    inet:setopts(Socket,[{active,once}]),
-    receive
-	{relay_to_ssl_node, Data} when is_binary(Data) ->
-	    case gen_tcp:send(Socket, Data) of
-		ok ->
-		    ok;
-		_Error ->
-		    gen_tcp:close(Socket),
-		    exit({failed_to_relay_data_to_ssl_node, Name, Data})
-	    end;
-	{tcp, Socket, Bin} ->
-	    case catch binary_to_term(Bin) of
-		{'EXIT', _} ->
-		    gen_tcp:close(Socket),
-		    exit({bad_data_received_from_ssl_node, Name, Bin});
-		{format, FmtStr, ArgList} ->
-		    ?t:format(FmtStr, ArgList);
-		{message, Msg} ->
-		    ?t:format("Got message ~p", [Msg]),
-		    Parent ! Msg;
-		{apply_res, To, Ref, Res} ->
-		    To ! {Ref, Res};
-		bye ->
-		    ?t:format("Ssl node ~s stopped.~n", [Name]),
-		    gen_tcp:close(Socket),
-		    exit(normal);
-		Unknown ->
-		    exit({unexpected_message_from_ssl_node, Name, Unknown})
-	    end;
-	{tcp_closed, Socket} ->
-	    gen_tcp:close(Socket),
-	    exit({lost_connection_with_ssl_node, Name})
-    end,
-    tstsrvr_con_loop(Name, Socket, Parent).
-
-%%
-%% Connection handler ssl_node side
-%%
-
-% cnct2tstsrvr() is called via command line arg -run ...
-cnct2tstsrvr([Host, Port]) when is_list(Host), is_list(Port) ->
-    %% Spawn connection handler on ssl node side
-    ConnHandler
-	= spawn(fun () ->
-			case catch gen_tcp:connect(Host,
-						   list_to_integer(Port),
-						   [binary,
-						    {packet, 4},
-						    {active, false}]) of
-			    {ok, Socket} ->
-				notify_ssl_node_up(Socket),
-				ets:new(test_server_info,
-					[set,
-					 public,
-					 named_table,
-					 {keypos, 1}]),
-				ets:insert(test_server_info,
-					   {test_server_handler, self()}),
-				ssl_node_con_loop(Socket);
-			    Error ->
-				halt("Failed to connect to test server " ++
-					 lists:flatten(io_lib:format("Host:~p ~n Port:~p~n Error:~p~n",
-								     [Host, Port, Error])))
-			end
-		end),
-    spawn(fun () ->
-		  Mon = erlang:monitor(process, ConnHandler),
-		  receive
-		      {'DOWN', Mon, process, ConnHandler, Reason} ->
-			  receive after 1000 -> ok end,
-			  halt("test server connection handler terminated: " ++
-				   lists:flatten(io_lib:format("~p", [Reason])))
-		  end
-	  end).
-
-notify_ssl_node_up(Socket) ->
-    case catch gen_tcp:send(Socket,
-			    term_to_binary({ssl_node_up, node()})) of
-	ok -> ok;
-	_ -> halt("Failed to notify test server that I'm up")
-    end.
-
-send_to_tstsrvr(Term) ->
-    case catch ets:lookup_element(test_server_info, test_server_handler, 2) of
-	Hndlr when is_pid(Hndlr) ->
-	    Hndlr ! {relay_to_test_server, term_to_binary(Term)}, ok;
-	_ ->
-	    receive after 200 -> ok end,
-	    send_to_tstsrvr(Term)
-    end.
-
-ssl_node_con_loop(Socket) ->
-    inet:setopts(Socket,[{active,once}]),
-    receive
-	{relay_to_test_server, Data} when is_binary(Data) ->
-	    case gen_tcp:send(Socket, Data) of
-		ok ->
-		    ok;
-		_Error ->
-		    gen_tcp:close(Socket),
-		    halt("Failed to relay data to test server")
-	    end;
-	{tcp, Socket, Bin} ->
-	    case catch binary_to_term(Bin) of
-		{'EXIT', _} ->
-		    gen_tcp:close(Socket),
-		    halt("test server sent me bad data");
-		{apply, From, Ref, M, F, A} ->
-		    spawn_link(
-		      fun () ->
-			      send_to_tstsrvr({apply_res,
-					       From,
-					       Ref,
-					       (catch apply(M, F, A))})
-			  end);
-		{apply, From, Ref, Fun} ->
-		    spawn_link(fun () ->
-				       send_to_tstsrvr({apply_res,
-							From,
-							Ref,
-							(catch Fun())})
-			       end);
-		stop ->
-		    gen_tcp:send(Socket, term_to_binary(bye)),
-		    gen_tcp:close(Socket),
-		    init:stop(),
-		    receive after infinity -> ok end;
-		_Unknown ->
-		    halt("test server sent me an unexpected message")
-	    end;
-	{tcp_closed, Socket} ->
-	    halt("Lost connection to test server")
-    end,
-    ssl_node_con_loop(Socket).
-
 %%
 %% Setup ssl dist info
 %%
diff --git a/lib/ssl/test/ssl_dist_bench_SUITE.erl b/lib/ssl/test/ssl_dist_bench_SUITE.erl
new file mode 100644
index 0000000000..4d27564319
--- /dev/null
+++ b/lib/ssl/test/ssl_dist_bench_SUITE.erl
@@ -0,0 +1,481 @@
+%%%-------------------------------------------------------------------
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(ssl_dist_bench_SUITE).
+
+-include_lib("common_test/include/ct_event.hrl").
+-include_lib("public_key/include/public_key.hrl").
+
+%% CT meta
+-export([suite/0, all/0, groups/0,
+         init_per_suite/1, end_per_suite/1,
+         init_per_group/2, end_per_group/2,
+         init_per_testcase/2, end_per_testcase/2]).
+
+%% Test cases
+-export(
+   [setup/1,
+    roundtrip/1,
+    throughput_1024/1,
+    throughput_4096/1,
+    throughput_16384/1,
+    throughput_65536/1,
+    throughput_262144/1,
+    throughput_1048576/1]).
+
+%% Debug
+-export([payload/1]).
+
+%%%-------------------------------------------------------------------
+
+suite() -> [{ct_hooks, [{ts_install_cth, [{nodenames, 2}]}]}].
+
+all() -> [{group, ssl}, {group, plain}].
+
+groups() ->
+    [{ssl, all_groups()},
+     {plain, all_groups()},
+     %%
+     {setup, [{repeat, 1}], [setup]},
+     {roundtrip, [{repeat, 1}], [roundtrip]},
+     {throughput, [{repeat, 1}],
+      [throughput_1024,
+       throughput_4096,
+       throughput_16384,
+       throughput_65536,
+       throughput_262144,
+       throughput_1048576]}].
+
+all_groups() ->
+    [{group, setup},
+     {group, roundtrip},
+     {group, throughput}].
+
+init_per_suite(Config) ->
+    Digest = sha1,
+    ECCurve = secp521r1,
+    TLSVersion = 'tlsv1.2',
+    TLSCipher = {ecdhe_ecdsa,aes_128_cbc,sha256,sha256},
+    %%
+    Node = node(),
+    try
+        Node =/= nonode@nohost orelse
+            throw({skipped,"Node not distributed"}),
+        {supported, SSLVersions} =
+            lists:keyfind(supported, 1, ssl:versions()),
+        lists:member(TLSVersion, SSLVersions) orelse
+            throw(
+              {skipped,
+               "SSL does not support " ++ term_to_string(TLSVersion)}),
+        lists:member(ECCurve, ssl:eccs(TLSVersion)) orelse
+            throw(
+              {skipped,
+               "SSL does not support " ++ term_to_string(ECCurve)}),
+        lists:member(TLSCipher, ssl:cipher_suites()) orelse
+            throw(
+              {skipped,
+               "SSL does not support " ++ term_to_string(TLSCipher)})
+    of
+        _ ->
+            PrivDir = proplists:get_value(priv_dir, Config),
+            %%
+            [_, HostA] = string:split(atom_to_list(Node), "@"),
+            NodeAName = ?MODULE_STRING ++ "_node_a",
+            NodeAString = NodeAName ++ "@" ++ HostA,
+            NodeAConfFile = filename:join(PrivDir, NodeAString ++ ".conf"),
+            NodeA = list_to_atom(NodeAString),
+            %%
+            ServerNode = ssl_bench_test_lib:setup(dist_server),
+            [_, HostB] = string:split(atom_to_list(ServerNode), "@"),
+            NodeBName = ?MODULE_STRING ++ "_node_b",
+            NodeBString = NodeBName ++ "@" ++ HostB,
+            NodeBConfFile = filename:join(PrivDir, NodeBString ++ ".conf"),
+            NodeB = list_to_atom(NodeBString),
+            %%
+            CertOptions =
+                [{digest, Digest},
+                 {key, {namedCurve, ECCurve}}],
+            RootCert =
+                public_key:pkix_test_root_cert(
+                  ?MODULE_STRING ++ " ROOT CA", CertOptions),
+            SSLConf =
+                [{verify, verify_peer},
+                 {versions, [TLSVersion]},
+                 {ciphers, [TLSCipher]}],
+            %%
+            write_node_conf(
+              NodeAConfFile, NodeA,
+              [{fail_if_no_peer_cert, true} | SSLConf], SSLConf,
+              CertOptions, RootCert),
+            write_node_conf(
+              NodeBConfFile, NodeB,
+              [{fail_if_no_peer_cert, true} | SSLConf], SSLConf,
+              CertOptions, RootCert),
+            %%
+            [{node_a_name, NodeAName},
+             {node_a, NodeA},
+             {node_a_dist_args,
+              "-proto_dist inet_tls "
+              "-ssl_dist_optfile " ++ NodeAConfFile ++ " "},
+             {node_b_name, NodeBName},
+             {node_b, NodeB},
+             {node_b_dist_args,
+              "-proto_dist inet_tls "
+              "-ssl_dist_optfile " ++ NodeBConfFile ++ " "},
+             {server_node, ServerNode}
+             |Config]
+    catch
+        throw:Result ->
+            Result
+    end.
+
+end_per_suite(Config) ->
+    ServerNode = proplists:get_value(server_node, Config),
+    slave:stop(ServerNode).
+
+init_per_group(ssl, Config) ->
+    [{ssl_dist, true}, {ssl_dist_prefix, "SSL"}|Config];
+init_per_group(plain, Config) ->
+    [{ssl_dist, false}, {ssl_dist_prefix, "Plain"}|Config];
+init_per_group(_GroupName, Config) ->
+    Config.
+
+end_per_group(_GroupName, _Config) ->
+    ok.
+
+init_per_testcase(_Func, Conf) ->
+    Conf.
+
+end_per_testcase(_Func, _Conf) ->
+    ok.
+
+-define(COUNT, 400).
+
+%%%-------------------------------------------------------------------
+%%% CommonTest API helpers
+
+write_node_conf(
+  ConfFile, Node, ServerConf, ClientConf, CertOptions, RootCert) ->
+    Conf =
+        public_key:pkix_test_data(
+          #{root => RootCert,
+            peer =>
+                [{extensions,
+                  [#'Extension'{
+                      extnID = ?'id-ce-subjectAltName',
+                      extnValue = [{dNSName, atom_to_list(Node)}],
+                      critical = false}]} | CertOptions]}),
+    NodeConf =
+        [{server, ServerConf ++ Conf}, {client, ClientConf ++ Conf}],
+    {ok, Fd} = file:open(ConfFile, [write]),
+    ok = file:change_mode(ConfFile, 8#400),
+    io:format(Fd, "~p.~n", [NodeConf]),
+    ok = file:close(Fd).
+
+
+%%%-------------------------------------------------------------------
+%%% Test cases
+
+%%-----------------------
+%% Connection setup speed
+
+setup(Config) ->
+    run_nodepair_test(fun setup/5, Config).
+
+setup(A, B, Prefix, HA, HB) ->
+    Rounds = 10,
+    [] = ssl_apply(HA, erlang, nodes, []),
+    [] = ssl_apply(HB, erlang, nodes, []),
+    {SetupTime, CycleTime} =
+        ssl_apply(HA, fun () -> setup_runner(A, B, Rounds) end),
+    [] = ssl_apply(HA, erlang, nodes, []),
+    [] = ssl_apply(HB, erlang, nodes, []),
+    SetupSpeed = round((Rounds*1000000*1000) / SetupTime),
+    CycleSpeed = round((Rounds*1000000*1000) / CycleTime),
+    _ = report(Prefix++" Setup", SetupSpeed, "setups/1000s"),
+    report(Prefix++" Setup Cycle", CycleSpeed, "cycles/1000s").
+
+%% Runs on node A against rex in node B
+setup_runner(A, B, Rounds) ->
+    StartTime = start_time(),
+    SetupTime = setup_loop(A, B, 0, Rounds),
+    {microseconds(SetupTime), microseconds(elapsed_time(StartTime))}.
+
+setup_loop(_A, _B, T, 0) ->
+    T;
+setup_loop(A, B, T, N) ->
+    StartTime = start_time(),
+    [A] = rpc:block_call(B, erlang, nodes, []),
+    Time = elapsed_time(StartTime),
+    [B] = erlang:nodes(),
+    Mref = erlang:monitor(process, {rex,B}),
+    true = net_kernel:disconnect(B),
+    receive
+        {'DOWN',Mref,process,_,_} ->
+            [] = erlang:nodes(),
+            setup_loop(A, B, Time + T, N - 1)
+    end.
+
+
+%%----------------
+%% Roundtrip speed
+
+roundtrip(Config) ->
+    run_nodepair_test(fun roundtrip/5, Config).
+
+roundtrip(A, B, Prefix, HA, HB) ->
+    Rounds = 40000,
+    [] = ssl_apply(HA, erlang, nodes, []),
+    [] = ssl_apply(HB, erlang, nodes, []),
+    Time = ssl_apply(HA, fun () -> roundtrip_runner(A, B, Rounds) end),
+    [B] = ssl_apply(HA, erlang, nodes, []),
+    [A] = ssl_apply(HB, erlang, nodes, []),
+    Speed = round((Rounds*1000000) / Time),
+    report(Prefix++" Roundtrip", Speed, "pings/s").
+
+%% Runs on node A and spawns a server on node B
+roundtrip_runner(A, B, Rounds) ->
+    ClientPid = self(),
+    [A] = rpc:call(B, erlang, nodes, []),
+    ServerPid =
+        erlang:spawn(
+          B,
+          fun () -> roundtrip_server(ClientPid, Rounds) end),
+    ServerMon = erlang:monitor(process, ServerPid),
+    microseconds(
+      roundtrip_client(ServerPid, ServerMon, start_time(), Rounds)).
+
+roundtrip_server(_Pid, 0) ->
+    ok;
+roundtrip_server(Pid, N) ->
+    receive
+        N ->
+            Pid ! N,
+            roundtrip_server(Pid, N-1)
+    end.
+
+roundtrip_client(_Pid, Mon, StartTime, 0) ->
+    Time = elapsed_time(StartTime),
+    receive
+        {'DOWN', Mon, _, _, normal} ->
+            Time;
+        {'DOWN', Mon, _, _, Other} ->
+            exit(Other)
+    end;
+roundtrip_client(Pid, Mon, StartTime, N) ->
+    Pid ! N,
+    receive
+        N ->
+            roundtrip_client(Pid, Mon, StartTime, N - 1)
+    end.
+
+
+%%-----------------
+%% Throughput speed
+
+throughput_1024(Config) ->
+    run_nodepair_test(
+      fun (A, B, Prefix, HA, HB) ->
+              throughput(A, B, Prefix, HA, HB, 100000, 1024)
+      end, Config).
+
+throughput_4096(Config) ->
+    run_nodepair_test(
+      fun (A, B, Prefix, HA, HB) ->
+              throughput(A, B, Prefix, HA, HB, 50000, 4096)
+      end, Config).
+
+throughput_16384(Config) ->
+    run_nodepair_test(
+      fun (A, B, Prefix, HA, HB) ->
+              throughput(A, B, Prefix, HA, HB, 10000, 16384)
+      end, Config).
+
+throughput_65536(Config) ->
+    run_nodepair_test(
+      fun (A, B, Prefix, HA, HB) ->
+              throughput(A, B, Prefix, HA, HB, 2000, 65536)
+      end, Config).
+
+throughput_262144(Config) ->
+    run_nodepair_test(
+      fun (A, B, Prefix, HA, HB) ->
+              throughput(A, B, Prefix, HA, HB, 500, 262144)
+      end, Config).
+
+throughput_1048576(Config) ->
+    run_nodepair_test(
+      fun (A, B, Prefix, HA, HB) ->
+              throughput(A, B, Prefix, HA, HB, 200, 1048576)
+      end, Config).
+
+throughput(A, B, Prefix, HA, HB, Packets, Size) ->
+    [] = ssl_apply(HA, erlang, nodes, []),
+    [] = ssl_apply(HB, erlang, nodes, []),
+    Time =
+        ssl_apply(HA, fun () -> throughput_runner(A, B, Packets, Size) end),
+    [B] = ssl_apply(HA, erlang, nodes, []),
+    [A] = ssl_apply(HB, erlang, nodes, []),
+    Speed = round((Packets*Size*1000000) / (1024*Time)),
+    report(Prefix++" Throughput_"++integer_to_list(Size), Speed, "kB/s").
+
+%% Runs on node A and spawns a server on node B
+throughput_runner(A, B, Rounds, Size) ->
+    Payload = payload(Size),
+    ClientPid = self(),
+    [A] = rpc:call(B, erlang, nodes, []),
+    ServerPid =
+        erlang:spawn(
+          B,
+          fun () -> throughput_server(ClientPid, Rounds) end),
+    ServerMon = erlang:monitor(process, ServerPid),
+    microseconds(
+      throughput_client(
+        ServerPid, ServerMon, Payload, start_time(), Rounds)).
+
+throughput_server(_Pid, 0) ->
+    ok;
+throughput_server(Pid, N) ->
+    receive
+        [N|_] ->
+            throughput_server(Pid, N-1)
+    end.
+
+throughput_client(_Pid, Mon, _Payload, StartTime, 0) ->
+    receive
+        {'DOWN', Mon, _, _, normal} ->
+            elapsed_time(StartTime);
+        {'DOWN', Mon, _, _, Other} ->
+            exit(Other)
+    end;
+throughput_client(Pid, Mon, Payload, StartTime, N) ->
+    Pid ! [N|Payload],
+    throughput_client(Pid, Mon, Payload, StartTime, N - 1).
+
+%%%-------------------------------------------------------------------
+%%% Test cases helpers
+
+run_nodepair_test(TestFun, Config) ->
+    A = proplists:get_value(node_a, Config),
+    B = proplists:get_value(node_b, Config),
+    Prefix = proplists:get_value(ssl_dist_prefix, Config),
+    HA = start_ssl_node_a(Config),
+    HB = start_ssl_node_b(Config),
+    try TestFun(A, B, Prefix, HA, HB)
+    after
+        stop_ssl_node_a(HA),
+        stop_ssl_node_b(HB, Config),
+        ok
+    end.
+
+ssl_apply(Handle, M, F, Args) ->
+    case ssl_dist_test_lib:apply_on_ssl_node(Handle, M, F, Args) of
+        {'EXIT',Reason} ->
+            error(Reason);
+        Result ->
+            Result
+    end.
+
+ssl_apply(Handle, Fun) ->
+    case ssl_dist_test_lib:apply_on_ssl_node(Handle, Fun) of
+        {'EXIT',Reason} ->
+            error(Reason);
+        Result ->
+            Result
+    end.
+
+start_ssl_node_a(Config) ->
+    Name = proplists:get_value(node_a_name, Config),
+    Args = get_node_args(node_a_dist_args, Config),
+    ssl_dist_test_lib:start_ssl_node(Name, Args).
+
+start_ssl_node_b(Config) ->
+    Name = proplists:get_value(node_b_name, Config),
+    Args = get_node_args(node_b_dist_args, Config),
+    ServerNode = proplists:get_value(server_node, Config),
+    rpc:call(
+      ServerNode, ssl_dist_test_lib, start_ssl_node, [Name, Args]).
+
+stop_ssl_node_a(HA) ->
+    ssl_dist_test_lib:stop_ssl_node(HA).
+
+stop_ssl_node_b(HB, Config) ->
+    ServerNode = proplists:get_value(server_node, Config),
+    rpc:call(ServerNode, ssl_dist_test_lib, stop_ssl_node, [HB]).
+
+get_node_args(Tag, Config) ->
+    case proplists:get_value(ssl_dist, Config) of
+        true ->
+            proplists:get_value(Tag, Config);
+        false ->
+            ""
+    end.
+
+
+
+payload(Size) ->
+    iolist_to_binary(
+      [case Size bsr 8 of
+           0 ->
+               [];
+           Blocks ->
+               payload(Blocks, create_binary(256))
+       end | create_binary(Size band 255)]).
+%%
+payload(0, _) ->
+    [];
+payload(Blocks, Block) ->
+    Half = payload(Blocks bsr 1, Block),
+    [Half, Half |
+     if
+         Blocks band 1 =:= 1 ->
+             Block;
+         true ->
+             []
+     end].
+
+create_binary(Size) ->
+    create_binary(Size, <<>>).
+%%
+create_binary(0, Bin) ->
+    Bin;
+create_binary(Size, Bin) ->
+    NextSize = Size - 1,
+    create_binary(NextSize, <<Bin/binary, NextSize>>).
+
+start_time() ->
+    erlang:system_time().
+
+elapsed_time(StartTime) ->
+    erlang:system_time() - StartTime.
+
+microseconds(Time) ->
+    erlang:convert_time_unit(Time, native, microsecond).
+
+report(Name, Value, Unit) ->
+    ct:pal("~s: ~w ~s", [Name, Value, Unit]),
+    ct_event:notify(
+      #event{
+         name = benchmark_data,
+         data = [{value, Value}, {suite, "ssl_dist"}, {name, Name}]}),
+    {comment, term_to_string(Value) ++ " " ++ Unit}.
+
+term_to_string(Term) ->
+    unicode:characters_to_list(
+      io_lib:write(Term, [{encoding, unicode}])).
diff --git a/lib/ssl/test/ssl_dist_test_lib.erl b/lib/ssl/test/ssl_dist_test_lib.erl
new file mode 100644
index 0000000000..1b9c853fc4
--- /dev/null
+++ b/lib/ssl/test/ssl_dist_test_lib.erl
@@ -0,0 +1,343 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+
+-module(ssl_dist_test_lib).
+
+-include_lib("common_test/include/ct.hrl").
+-include_lib("public_key/include/public_key.hrl").
+-include("ssl_dist_test_lib.hrl").
+
+-export([tstsrvr_format/2, send_to_tstcntrl/1]).
+-export([apply_on_ssl_node/4, apply_on_ssl_node/2]).
+-export([stop_ssl_node/1, start_ssl_node/2]).
+%%
+-export([cnct2tstsrvr/1]).
+
+-define(AWAIT_SSL_NODE_UP_TIMEOUT, 30000).
+
+
+
+%% ssl_node side api
+%%
+
+tstsrvr_format(Fmt, ArgList) ->
+    send_to_tstsrvr({format, Fmt, ArgList}).
+
+send_to_tstcntrl(Message) ->
+    send_to_tstsrvr({message, Message}).
+
+
+%%
+%% test_server side api
+%%
+
+apply_on_ssl_node(
+  #node_handle{connection_handler = Hndlr} = Node,
+  M, F, A) when is_atom(M), is_atom(F), is_list(A) ->
+    Ref = erlang:monitor(process, Hndlr),
+    apply_on_ssl_node(Node, Ref, {apply, self(), Ref, M, F, A}).
+
+apply_on_ssl_node(
+  #node_handle{connection_handler = Hndlr} = Node,
+  Fun) when is_function(Fun, 0) ->
+    Ref = erlang:monitor(process, Hndlr),
+    apply_on_ssl_node(Node, Ref, {apply, self(), Ref, Fun}).
+
+apply_on_ssl_node(Node, Ref, Msg) ->
+    send_to_ssl_node(Node, Msg),
+    receive
+        {'DOWN', Ref, process, Hndlr, Reason} ->
+            exit({handler_died, Hndlr, Reason});
+	{Ref, Result} ->
+	    Result
+    end.
+
+stop_ssl_node(#node_handle{connection_handler = Handler,
+			   socket = Socket,
+			   name = Name}) ->
+    ?t:format("Trying to stop ssl node ~s.~n", [Name]),
+    Mon = erlang:monitor(process, Handler),
+    unlink(Handler),
+    case gen_tcp:send(Socket, term_to_binary(stop)) of
+	ok ->
+	    receive
+		{'DOWN', Mon, process, Handler, Reason} ->
+		    case Reason of
+			normal ->
+			    ok;
+			_ ->
+			    ct:pal(
+                              "stop_ssl_node/1 ~s Down  ~p ~n",
+                              [Name,Reason])
+		    end
+	    end;
+	Error ->
+	    erlang:demonitor(Mon, [flush]),
+	    ct:pal("stop_ssl_node/1 ~s Warning ~p ~n", [Name,Error])
+    end.
+
+start_ssl_node(Name, Args) ->
+    {ok, LSock} = gen_tcp:listen(0,
+				 [binary, {packet, 4}, {active, false}]),
+    {ok, ListenPort} = inet:port(LSock),
+    CmdLine = mk_node_cmdline(ListenPort, Name, Args),
+    ?t:format("Attempting to start ssl node ~ts: ~ts~n", [Name, CmdLine]),
+    case open_port({spawn, CmdLine}, []) of
+	Port when is_port(Port) ->
+	    unlink(Port),
+	    erlang:port_close(Port),
+	    case await_ssl_node_up(Name, LSock) of
+		#node_handle{} = NodeHandle ->
+		    ?t:format("Ssl node ~s started.~n", [Name]),
+		    NodeName = list_to_atom(Name ++ "@" ++ host_name()),
+		    NodeHandle#node_handle{nodename = NodeName};
+		Error ->
+		    exit({failed_to_start_node, Name, Error})
+	    end;
+	Error ->
+	    exit({failed_to_start_node, Name, Error})
+    end.
+
+host_name() ->
+    [_, Host] = string:split(atom_to_list(node()), "@"),
+    %% [$@ | Host] = lists:dropwhile(fun ($@) -> false; (_) -> true end,
+    %%     			  atom_to_list(node())),
+    Host.
+
+mk_node_cmdline(ListenPort, Name, Args) ->
+    Static = "-detached -noinput",
+    Pa = filename:dirname(code:which(?MODULE)),
+    Prog = case catch init:get_argument(progname) of
+	       {ok,[[P]]} -> P;
+	       _ -> exit(no_progname_argument_found)
+	   end,
+    NameSw = case net_kernel:longnames() of
+		 false -> "-sname ";
+		 _ -> "-name "
+	     end,
+    {ok, Pwd} = file:get_cwd(),
+    "\"" ++ Prog ++ "\" "
+	++ Static ++ " "
+	++ NameSw ++ " " ++ Name ++ " "
+	++ "-pa " ++ Pa ++ " "
+	++ "-run application start crypto -run application start public_key "
+	++ "-eval 'net_kernel:verbose(1)' "
+	++ "-run " ++ atom_to_list(?MODULE) ++ " cnct2tstsrvr "
+	++ host_name() ++ " "
+	++ integer_to_list(ListenPort) ++ " "
+	++ Args ++ " "
+	++ "-env ERL_CRASH_DUMP " ++ Pwd ++ "/erl_crash_dump." ++ Name ++ " "
+	++ "-kernel error_logger \"{file,\\\"" ++ Pwd ++ "/error_log." ++ Name ++ "\\\"}\" "
+	++ "-setcookie " ++ atom_to_list(erlang:get_cookie()).
+
+%%
+%% Connection handler test_server side
+%%
+
+await_ssl_node_up(Name, LSock) ->
+    case gen_tcp:accept(LSock, ?AWAIT_SSL_NODE_UP_TIMEOUT) of
+	{ok, Socket} ->
+	    gen_tcp:close(LSock),
+	    case gen_tcp:recv(Socket, 0) of
+		{ok, Bin} ->
+		    check_ssl_node_up(Socket, Name, Bin);
+		{error, closed} ->
+		    gen_tcp:close(Socket),
+		    exit({lost_connection_with_ssl_node_before_up, Name})
+	    end;
+	{error, Error} ->
+	    gen_tcp:close(LSock),
+            ?t:format("Accept failed for ssl node ~s: ~p~n", [Name,Error]),
+	    exit({accept_failed, Error})
+    end.
+
+check_ssl_node_up(Socket, Name, Bin) ->
+    case catch binary_to_term(Bin) of
+	{'EXIT', _} ->
+	    gen_tcp:close(Socket),
+	    exit({bad_data_received_from_ssl_node, Name, Bin});
+	{ssl_node_up, NodeName} ->
+	    case list_to_atom(Name++"@"++host_name()) of
+		NodeName ->
+		    Parent = self(),
+		    Go = make_ref(),
+		    %% Spawn connection handler on test server side
+		    Pid = spawn_link(
+			    fun () ->
+				    receive Go -> ok end,
+                                    process_flag(trap_exit, true),
+				    tstsrvr_con_loop(Name, Socket, Parent)
+			    end),
+		    ok = gen_tcp:controlling_process(Socket, Pid),
+		    Pid ! Go,
+		    #node_handle{connection_handler = Pid,
+				 socket = Socket,
+				 name = Name};
+		_ ->
+		    exit({unexpected_ssl_node_connected, NodeName})
+	    end;
+	Msg ->
+	    exit({unexpected_msg_instead_of_ssl_node_up, Name, Msg})
+    end.
+
+send_to_ssl_node(#node_handle{connection_handler = Hndlr}, Term) ->
+    Hndlr ! {relay_to_ssl_node, term_to_binary(Term)},
+    ok.
+
+tstsrvr_con_loop(Name, Socket, Parent) ->
+    ok = inet:setopts(Socket,[{active,once}]),
+    receive
+	{relay_to_ssl_node, Data} when is_binary(Data) ->
+	    case gen_tcp:send(Socket, Data) of
+		ok ->
+		    ok;
+		_Error ->
+		    gen_tcp:close(Socket),
+		    exit({failed_to_relay_data_to_ssl_node, Name, Data})
+	    end;
+	{tcp, Socket, Bin} ->
+	    try binary_to_term(Bin) of
+		{format, FmtStr, ArgList} ->
+		    ?t:format(FmtStr, ArgList);
+		{message, Msg} ->
+		    ?t:format("Got message ~p", [Msg]),
+		    Parent ! Msg;
+		{apply_res, To, Ref, Res} ->
+		    To ! {Ref, Res};
+		bye ->
+                    {error, closed} = gen_tcp:recv(Socket, 0),
+		    ?t:format("Ssl node ~s stopped.~n", [Name]),
+		    gen_tcp:close(Socket),
+		    exit(normal);
+		Unknown ->
+		    exit({unexpected_message_from_ssl_node, Name, Unknown})
+            catch
+                error : _ ->
+		    gen_tcp:close(Socket),
+		    exit({bad_data_received_from_ssl_node, Name, Bin})
+	    end;
+	{tcp_closed, Socket} ->
+	    gen_tcp:close(Socket),
+	    exit({lost_connection_with_ssl_node, Name});
+        {'EXIT', Parent, Reason} ->
+            exit({'EXIT', parent, Reason});
+        Unknown ->
+            exit({unknown, Unknown})
+    end,
+    tstsrvr_con_loop(Name, Socket, Parent).
+
+%%
+%% Connection handler ssl_node side
+%%
+
+% cnct2tstsrvr() is called via command line arg -run ...
+cnct2tstsrvr([Host, Port]) when is_list(Host), is_list(Port) ->
+    %% Spawn connection handler on ssl node side
+    ConnHandler
+	= spawn(fun () ->
+			case catch gen_tcp:connect(Host,
+						   list_to_integer(Port),
+						   [binary,
+						    {packet, 4},
+						    {active, false}]) of
+			    {ok, Socket} ->
+				notify_ssl_node_up(Socket),
+				ets:new(test_server_info,
+					[set,
+					 public,
+					 named_table,
+					 {keypos, 1}]),
+				ets:insert(test_server_info,
+					   {test_server_handler, self()}),
+				ssl_node_con_loop(Socket);
+			    Error ->
+				halt("Failed to connect to test server " ++
+					 lists:flatten(io_lib:format("Host:~p ~n Port:~p~n Error:~p~n",
+								     [Host, Port, Error])))
+			end
+		end),
+    spawn(fun () ->
+		  Mon = erlang:monitor(process, ConnHandler),
+		  receive
+		      {'DOWN', Mon, process, ConnHandler, Reason} ->
+			  receive after 1000 -> ok end,
+			  halt("test server connection handler terminated: " ++
+				   lists:flatten(io_lib:format("~p", [Reason])))
+		  end
+	  end).
+
+notify_ssl_node_up(Socket) ->
+    case catch gen_tcp:send(Socket,
+			    term_to_binary({ssl_node_up, node()})) of
+	ok -> ok;
+	_ -> halt("Failed to notify test server that I'm up")
+    end.
+
+send_to_tstsrvr(Term) ->
+    case catch ets:lookup_element(test_server_info, test_server_handler, 2) of
+	Hndlr when is_pid(Hndlr) ->
+	    Hndlr ! {relay_to_test_server, term_to_binary(Term)}, ok;
+	_ ->
+	    receive after 200 -> ok end,
+	    send_to_tstsrvr(Term)
+    end.
+
+ssl_node_con_loop(Socket) ->
+    inet:setopts(Socket,[{active,once}]),
+    receive
+	{relay_to_test_server, Data} when is_binary(Data) ->
+	    case gen_tcp:send(Socket, Data) of
+		ok ->
+		    ok;
+		_Error ->
+		    gen_tcp:close(Socket),
+		    halt("Failed to relay data to test server")
+	    end;
+	{tcp, Socket, Bin} ->
+	    case catch binary_to_term(Bin) of
+		{'EXIT', _} ->
+		    gen_tcp:close(Socket),
+		    halt("test server sent me bad data");
+		{apply, From, Ref, M, F, A} ->
+		    spawn_link(
+		      fun () ->
+			      send_to_tstsrvr({apply_res,
+					       From,
+					       Ref,
+					       (catch apply(M, F, A))})
+			  end);
+		{apply, From, Ref, Fun} ->
+		    spawn_link(fun () ->
+				       send_to_tstsrvr({apply_res,
+							From,
+							Ref,
+							(catch Fun())})
+			       end);
+		stop ->
+		    gen_tcp:send(Socket, term_to_binary(bye)),
+		    init:stop(),
+		    receive after infinity -> ok end;
+		_Unknown ->
+		    halt("test server sent me an unexpected message")
+	    end;
+	{tcp_closed, Socket} ->
+	    halt("Lost connection to test server")
+    end,
+    ssl_node_con_loop(Socket).
diff --git a/lib/ssl/test/ssl_dist_test_lib.hrl b/lib/ssl/test/ssl_dist_test_lib.hrl
new file mode 100644
index 0000000000..86b9b37026
--- /dev/null
+++ b/lib/ssl/test/ssl_dist_test_lib.hrl
@@ -0,0 +1,26 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+
+-record(node_handle,
+	{connection_handler,
+	 socket,
+	 name,
+	 nodename}
+       ).
diff --git a/lib/ssl/test/ssl_test_lib.erl b/lib/ssl/test/ssl_test_lib.erl
index 7248411d15..03c3ed9be3 100644
--- a/lib/ssl/test/ssl_test_lib.erl
+++ b/lib/ssl/test/ssl_test_lib.erl
@@ -1539,10 +1539,14 @@ is_psk_anon_suite({psk, _,_}) ->
     true;
 is_psk_anon_suite({dhe_psk,_,_}) ->
     true;
+is_psk_anon_suite({ecdhe_psk,_,_}) ->
+    true;
 is_psk_anon_suite({psk, _,_,_}) ->
     true;
 is_psk_anon_suite({dhe_psk, _,_,_}) ->
     true;
+is_psk_anon_suite({ecdhe_psk, _,_,_}) ->
+    true;
 is_psk_anon_suite(_) ->
     false.
 
diff --git a/lib/stdlib/doc/src/Makefile b/lib/stdlib/doc/src/Makefile
index e7ea38c5c3..af27efa6c1 100644
--- a/lib/stdlib/doc/src/Makefile
+++ b/lib/stdlib/doc/src/Makefile
@@ -98,6 +98,7 @@ XML_REF3_FILES = \
 	sys.xml \
 	timer.xml \
 	unicode.xml \
+	uri_string.xml \
 	win32reg.xml \
 	zip.xml
 
diff --git a/lib/stdlib/doc/src/c.xml b/lib/stdlib/doc/src/c.xml
index 7666699183..697e1715e7 100644
--- a/lib/stdlib/doc/src/c.xml
+++ b/lib/stdlib/doc/src/c.xml
@@ -94,6 +94,15 @@
     </func>
 
     <func>
+      <name name="erlangrc" arity="1"/>
+      <fsummary>Load an erlang resource file.</fsummary>
+      <desc>
+        <p>Search <c>PathList</c> and load <c>.erlang</c> resource file if
+	found.</p>
+      </desc>
+    </func>
+
+    <func>
       <name name="flush" arity="0"/>
       <fsummary>Flush any messages sent to the shell.</fsummary>
       <desc>
diff --git a/lib/stdlib/doc/src/ets.xml b/lib/stdlib/doc/src/ets.xml
index 576959b1c8..a0ec22c515 100644
--- a/lib/stdlib/doc/src/ets.xml
+++ b/lib/stdlib/doc/src/ets.xml
@@ -1961,7 +1961,7 @@ true</pre>
           The return value is a list of the new counter values from each 
           update operation in the same order as in the operation list. If an 
           empty list is specified, nothing is updated and an empty list is 
-          returned. If the function fails, no updates is done.</p>
+          returned. If the function fails, no updates are done.</p>
         <p>The specified <c><anno>Key</anno></c> is used to identify the object
           by either <em>matching</em> the key of an object in a <c>set</c>
           table, or <em>compare equal</em> to the key of an object in an
diff --git a/lib/stdlib/doc/src/filelib.xml b/lib/stdlib/doc/src/filelib.xml
index 80c4acffdb..5e631aac21 100644
--- a/lib/stdlib/doc/src/filelib.xml
+++ b/lib/stdlib/doc/src/filelib.xml
@@ -45,6 +45,30 @@
 
     <p>For more information about raw filenames, see the
       <seealso marker="kernel:file"><c>file</c></seealso> module.</p>
+
+    <note>
+      <p>
+	Functionality in this module generally assumes valid input and
+	does not necessarily fail on input that does not use a valid
+	encoding, but may instead very likely produce invalid output.
+      </p>
+      <p>
+	File operations used to accept filenames containing
+	null characters (integer value zero). This caused
+	the name to be truncated and in some cases arguments
+	to primitive operations to be mixed up. Filenames
+	containing null characters inside the filename
+	are now <em>rejected</em> and will cause primitive
+	file operations to fail.
+      </p>
+    </note>
+    <warning><p>
+      Currently null characters at the end of the filename
+      will be accepted by primitive file operations. Such
+      filenames are however still documented as invalid. The
+      implementation will also change in the future and
+      reject such filenames.
+    </p></warning>
   </description>
 
   <datatypes>
@@ -193,6 +217,11 @@
         <p>Other characters represent themselves. Only filenames that
           have exactly the same character in the same position match.
           Matching is case-sensitive, for example, "a" does not match "A".</p>
+	<p>Directory separators must always be written as <c>/</c>, even on
+	Windows.</p>
+	<p>A character preceded by <c>\</c> loses its special meaning. Note
+	that <c>\</c> must be written as <c>\\</c> in a string literal.
+	For example, "\\?*" will match any filename starting with <c>?</c>.</p>
         <p>Notice that multiple "*" characters are allowed
           (as in Unix wildcards, but opposed to Windows/DOS wildcards).</p>
         <p><em>Examples:</em></p>
diff --git a/lib/stdlib/doc/src/filename.xml b/lib/stdlib/doc/src/filename.xml
index 14fd5ef787..d2608ad542 100644
--- a/lib/stdlib/doc/src/filename.xml
+++ b/lib/stdlib/doc/src/filename.xml
@@ -46,7 +46,10 @@
       filename by removing redundant directory separators, use
       <seealso marker="#join/1"><c>join/1</c></seealso>.</p>
 
-    <p>The module supports raw filenames in the way that if a binary is
+    <p>
+      The module supports
+      <seealso marker="unicode_usage#notes-about-raw-filenames">raw
+      filenames</seealso> in the way that if a binary is
       present, or the filename cannot be interpreted according to the return
       value of <seealso marker="kernel:file#native_name_encoding/0">
       <c>file:native_name_encoding/0</c></seealso>, a raw filename is also
@@ -56,6 +59,30 @@
       (the join operation is performed of course). For more information
       about raw filenames, see the
       <seealso marker="kernel:file"><c>file</c></seealso> module.</p>
+
+    <note>
+      <p>
+	Functionality in this module generally assumes valid input and
+	does not necessarily fail on input that does not use a valid
+	encoding, but may instead very likely produce invalid output.
+      </p>
+      <p>
+	File operations used to accept filenames containing
+	null characters (integer value zero). This caused
+	the name to be truncated and in some cases arguments
+	to primitive operations to be mixed up. Filenames
+	containing null characters inside the filename
+	are now <em>rejected</em> and will cause primitive
+	file operations to fail.
+      </p>
+    </note>
+    <warning><p>
+      Currently null characters at the end of the filename
+      will be accepted by primitive file operations. Such
+      filenames are however still documented as invalid. The
+      implementation will also change in the future and
+      reject such filenames.
+    </p></warning>
   </description>
   <datatypes>
       <datatype>
@@ -555,6 +582,7 @@ unsafe</pre>
 ["a:/","msdev","include"]</pre>
       </desc>
     </func>
+
   </funcs>
 </erlref>
 
diff --git a/lib/stdlib/doc/src/gen_server.xml b/lib/stdlib/doc/src/gen_server.xml
index 7d137fc772..da74e793e6 100644
--- a/lib/stdlib/doc/src/gen_server.xml
+++ b/lib/stdlib/doc/src/gen_server.xml
@@ -60,6 +60,8 @@ gen_server:abcast     -----> Module:handle_cast/2
 
 -                     -----> Module:handle_info/2
 
+-                     -----> Module:handle_continue/2
+
 -                     -----> Module:terminate/2
 
 -                     -----> Module:code_change/3</pre>
@@ -88,6 +90,13 @@ gen_server:abcast     -----> Module:handle_cast/2
       implies at least two garbage collections (when hibernating and
       shortly after waking up) and is not something you want to do
       between each call to a busy server.</p>
+
+    <p>If the <c>gen_server</c> process needs to perform an action
+      immediately after initialization or to break the execution of a
+      callback into multiple steps, it can return <c>{continue,Continue}</c>
+      in place of the time-out or hibernation value, which will immediately
+      invoke the <c>handle_continue/2</c> callback.</p>
+
   </description>
 
   <funcs>
@@ -610,12 +619,15 @@ gen_server:abcast     -----> Module:handle_cast/2
         <v>State = term()</v>
         <v>Result = {reply,Reply,NewState} | {reply,Reply,NewState,Timeout}</v> 
         <v>&nbsp;&nbsp;| {reply,Reply,NewState,hibernate}</v>
+        <v>&nbsp;&nbsp;| {reply,Reply,NewState,{continue,Continue}}</v>
         <v>&nbsp;&nbsp;| {noreply,NewState} | {noreply,NewState,Timeout}</v> 
         <v>&nbsp;&nbsp;| {noreply,NewState,hibernate}</v>
+        <v>&nbsp;&nbsp;| {noreply,NewState,{continue,Continue}}</v>
         <v>&nbsp;&nbsp;| {stop,Reason,Reply,NewState} | {stop,Reason,NewState}</v>
         <v>&nbsp;Reply = term()</v>
         <v>&nbsp;NewState = term()</v>
         <v>&nbsp;Timeout = int()>=0 | infinity</v>
+        <v>&nbsp;Continue = term()</v>
         <v>&nbsp;Reason = term()</v>
       </type>
       <desc>
@@ -673,9 +685,11 @@ gen_server:abcast     -----> Module:handle_cast/2
         <v>State = term()</v>
         <v>Result = {noreply,NewState} | {noreply,NewState,Timeout}</v>
         <v>&nbsp;&nbsp;| {noreply,NewState,hibernate}</v>
+        <v>&nbsp;&nbsp;| {noreply,NewState,{continue,Continue}}</v>
         <v>&nbsp;&nbsp;| {stop,Reason,NewState}</v>
         <v>&nbsp;NewState = term()</v>
         <v>&nbsp;Timeout = int()>=0 | infinity</v>
+        <v>&nbsp;Continue = term()</v>
         <v>&nbsp;Reason = term()</v>
       </type>
       <desc>
@@ -690,6 +704,41 @@ gen_server:abcast     -----> Module:handle_cast/2
     </func>
 
     <func>
+      <name>Module:handle_continue(Continue, State) -> Result</name>
+      <fsummary>Handle a continue instruction.</fsummary>
+      <type>
+        <v>Continue = term()</v>
+        <v>State = term()</v>
+        <v>Result = {noreply,NewState} | {noreply,NewState,Timeout}</v>
+        <v>&nbsp;&nbsp;| {noreply,NewState,hibernate}</v>
+        <v>&nbsp;&nbsp;| {noreply,NewState,{continue,Continue}}</v>
+        <v>&nbsp;&nbsp;| {stop,Reason,NewState}</v>
+        <v>&nbsp;NewState = term()</v>
+        <v>&nbsp;Timeout = int()>=0 | infinity</v>
+        <v>&nbsp;Continue = term()</v>
+        <v>&nbsp;Reason = normal | term()</v>
+      </type>
+      <desc>
+        <note>
+          <p>This callback is optional, so callback modules need to
+            export it only if they return <c>{continue,Continue}</c>
+            from another callback. If continue is used and the callback
+            is not implemented, the process will exit with <c>undef</c>
+            error.</p>
+        </note>
+        <p>This function is called by a <c>gen_server</c> process whenever
+          a previous callback returns <c>{continue, Continue}</c>.
+          <c>handle_continue/2</c> is invoked immediately after the previous
+          callback, which makes it useful for performing work after
+          initialization or for splitting the work in a callback in
+          multiple steps, updating the process state along the way.</p>
+        <p>For a description of the other arguments and possible return values,
+          see <seealso marker="#Module:handle_call/3">
+          <c>Module:handle_call/3</c></seealso>.</p>
+      </desc>
+    </func>
+
+    <func>
       <name>Module:handle_info(Info, State) -> Result</name>
       <fsummary>Handle an incoming message.</fsummary>
       <type>
@@ -697,6 +746,7 @@ gen_server:abcast     -----> Module:handle_cast/2
         <v>State = term()</v>
         <v>Result = {noreply,NewState} | {noreply,NewState,Timeout}</v>
         <v>&nbsp;&nbsp;| {noreply,NewState,hibernate}</v>
+        <v>&nbsp;&nbsp;| {noreply,NewState,{continue,Continue}}</v>
         <v>&nbsp;&nbsp;| {stop,Reason,NewState}</v>
         <v>&nbsp;NewState = term()</v>
         <v>&nbsp;Timeout = int()>=0 | infinity</v>
@@ -726,7 +776,7 @@ gen_server:abcast     -----> Module:handle_cast/2
       <type>
         <v>Args = term()</v>
         <v>Result =  {ok,State} | {ok,State,Timeout} | {ok,State,hibernate}</v>
-        <v>&nbsp;| {stop,Reason} | ignore</v>
+        <v>&nbsp;| {ok,State,{continue,Continue}} | {stop,Reason} | ignore</v>
         <v>&nbsp;State = term()</v>
         <v>&nbsp;Timeout = int()>=0 | infinity</v>
         <v>&nbsp;Reason = term()</v>
diff --git a/lib/stdlib/doc/src/gen_statem.xml b/lib/stdlib/doc/src/gen_statem.xml
index a7caa71dcb..4a824f073e 100644
--- a/lib/stdlib/doc/src/gen_statem.xml
+++ b/lib/stdlib/doc/src/gen_statem.xml
@@ -1329,7 +1329,7 @@ handle_event(_, _, State, Data) ->
 	  <c><anno>T</anno></c> is the time-out time.
 	  <c>{clean_timeout,<anno>T</anno>}</c> works like
 	  just <c>T</c> described in the note above
-	  and uses a proxy process for <c>T &lt; infinity</c>,
+	  and uses a proxy process
 	  while <c>{dirty_timeout,<anno>T</anno>}</c>
 	  bypasses the proxy process which is more lightweight.
 	</p>
@@ -1339,8 +1339,12 @@ handle_event(_, _, State, Data) ->
 	    with <c>{dirty_timeout,<anno>T</anno>}</c>
 	    to avoid that the calling process dies when the call
 	    times out, you will have to be prepared to handle
-	    a late reply.
-	    So why not just let the calling process die?
+	    a late reply.  Note that there is an odd chance
+	    to get a late reply even with
+	    <c>{dirty_timeout,infinity}</c> or <c>infinity</c>
+	    for example in the event of network problems.
+	    So why not just let the calling process die
+	    by not catching the exception?
 	  </p>
 	</note>
 	<p>
@@ -1851,7 +1855,7 @@ handle_event(_, _, State, Data) ->
 	</p>
         <note>
 	  <p>
-	    Note that if the <c>gen_statem</c> is started trough
+	    Note that if the <c>gen_statem</c> is started through
 	    <seealso marker="proc_lib"><c>proc_lib</c></seealso>
 	    and
 	    <seealso marker="#enter_loop/4"><c>enter_loop/4-6</c></seealso>,
diff --git a/lib/stdlib/doc/src/maps.xml b/lib/stdlib/doc/src/maps.xml
index 8c7270816b..987d92989d 100644
--- a/lib/stdlib/doc/src/maps.xml
+++ b/lib/stdlib/doc/src/maps.xml
@@ -33,16 +33,31 @@
     <p>This module contains functions for maps processing.</p>
   </description>
 
+  <datatypes>
+    <datatype>
+      <name name="iterator"/>
+      <desc>
+        <p>An iterator representing the key value associations in a map.</p>
+        <p>Created using <seealso marker="#iterator-1"><c>maps:iterator/1</c></seealso>.</p>
+        <p>Consumed by <seealso marker="#next-1"><c>maps:next/1</c></seealso>,
+          <seealso marker="#filter-2"><c>maps:filter/2</c></seealso>,
+          <seealso marker="#fold-3"><c>maps:fold/3</c></seealso> and
+          <seealso marker="#map-2"><c>maps:map/2</c></seealso>.</p>
+      </desc>
+    </datatype>
+  </datatypes>
+
   <funcs>
     <func>
       <name name="filter" arity="2"/>
       <fsummary>Select pairs that satisfy a predicate.</fsummary>
       <desc>
-        <p>Returns a map <c><anno>Map2</anno></c> for which predicate
-          <c><anno>Pred</anno></c> holds true in <c><anno>Map1</anno></c>.</p>
+        <p>Returns a map <c><anno>Map</anno></c> for which predicate
+          <c><anno>Pred</anno></c> holds true in <c><anno>MapOrIter</anno></c>.</p>
         <p>The call fails with a <c>{badmap,Map}</c> exception if
-          <c><anno>Map1</anno></c> is not a map, or with <c>badarg</c> if
-          <c><anno>Pred</anno></c> is not a function of arity 2.</p>
+          <c><anno>MapOrIter</anno></c> is not a map or valid iterator,
+          or with <c>badarg</c> if <c><anno>Pred</anno></c> is not a
+          function of arity 2.</p>
         <p><em>Example:</em></p>
         <code type="none">
 > M = #{a => 2, b => 3, c=> 4, "a" => 1, "b" => 2, "c" => 4},
@@ -76,12 +91,16 @@
       <fsummary></fsummary>
       <desc>
         <p>Calls <c>F(K, V, AccIn)</c> for every <c><anno>K</anno></c> to value
-          <c><anno>V</anno></c> association in <c><anno>Map</anno></c> in
+          <c><anno>V</anno></c> association in <c><anno>MapOrIter</anno></c> in
           any order. Function <c>fun F/3</c> must return a new
           accumulator, which is passed to the next successive call.
           This function returns the final value of the accumulator. The initial
           accumulator value <c><anno>Init</anno></c> is returned if the map is
           empty.</p>
+        <p>The call fails with a <c>{badmap,Map}</c> exception if
+          <c><anno>MapOrIter</anno></c> is not a map or valid iterator,
+          or with <c>badarg</c> if <c><anno>Fun</anno></c> is not a
+          function of arity 3.</p>
         <p><em>Example:</em></p>
         <code type="none">
 > Fun = fun(K,V,AccIn) when is_list(K) -> AccIn + V end,
@@ -169,6 +188,32 @@ false</code>
     </func>
 
     <func>
+      <name name="iterator" arity="1"/>
+      <fsummary>Create a map iterator.</fsummary>
+      <desc>
+        <p>Returns a map iterator <c><anno>Iterator</anno></c> that can
+          be used by <seealso marker="#next-1"><c>maps:next/1</c></seealso>
+          to traverse the key-value associations in a map. When iterating
+          over a map, the memory usage is guaranteed to be bounded no matter
+          the size of the map.</p>
+        <p>The call fails with a <c>{badmap,Map}</c> exception if
+          <c><anno>Map</anno></c> is not a map.</p>
+        <p><em>Example:</em></p>
+        <code type="none">
+> M = #{ a => 1, b => 2 }.
+#{a => 1,b => 2}
+> I = maps:iterator(M).
+[{a,1},{b,2}]
+> {K1, V1, I2} = maps:next(I).
+{a,1,[{b,2}]}
+> {K2, V2, I3} = maps:next(I2).
+{b,2,[]}
+> maps:next(I3).
+none</code>
+      </desc>
+    </func>
+
+    <func>
       <name name="keys" arity="1"/>
       <fsummary></fsummary>
       <desc>
@@ -188,12 +233,16 @@ false</code>
       <name name="map" arity="2"/>
       <fsummary></fsummary>
       <desc>
-        <p>Produces a new map <c><anno>Map2</anno></c> by calling function
+        <p>Produces a new map <c><anno>Map</anno></c> by calling function
           <c>fun F(K, V1)</c> for every <c><anno>K</anno></c> to value
-          <c><anno>V1</anno></c> association in <c><anno>Map1</anno></c> in
+          <c><anno>V1</anno></c> association in <c><anno>MapOrIter</anno></c> in
           any order. Function <c>fun F/2</c> must return value
           <c><anno>V2</anno></c> to be associated with key <c><anno>K</anno></c>
-          for the new map <c><anno>Map2</anno></c>.</p>
+          for the new map <c><anno>Map</anno></c>.</p>
+        <p>The call fails with a <c>{badmap,Map}</c> exception if
+          <c><anno>MapOrIter</anno></c> is not a map or valid iterator,
+          or with <c>badarg</c> if <c><anno>Fun</anno></c> is not a
+          function of arity 2.</p>
         <p><em>Example:</em></p>
         <code type="none">
 > Fun = fun(K,V1) when is_list(K) -> V1*2 end,
@@ -234,6 +283,35 @@ false</code>
     </func>
 
     <func>
+      <name name="next" arity="1"/>
+      <fsummary>Get the next key and value from an iterator.</fsummary>
+      <desc>
+        <p>Returns the next key-value association in
+          <c><anno>Iterator</anno></c> and a new iterator for the
+          remaining associations in the iterator.
+        </p>
+        <p>
+          If there are no more associations in the iterator,
+          <c>none</c> is returned.
+        </p>
+        <p><em>Example:</em></p>
+        <code type="none">
+> Map = #{a => 1, b => 2, c => 3}.
+#{a => 1,b => 2,c => 3}
+> Iter = maps:iterator(Map).
+[{a,1},{b,2},{c,3}]
+> {_, _, Iter1} = maps:next(Iter).
+{a,1,[{b,2},{c,3}]}
+> {_, _, Iter2} = maps:next(Iter1).
+{b,2,[{c,3}]}
+> {_, _, Iter3} = maps:next(Iter2).
+{c,3,[]}
+> maps:next(Iter3).
+none</code>
+      </desc>
+    </func>
+
+    <func>
       <name name="put" arity="3"/>
       <fsummary></fsummary>
       <desc>
diff --git a/lib/stdlib/doc/src/rand.xml b/lib/stdlib/doc/src/rand.xml
index 89fb858823..21f680a0ee 100644
--- a/lib/stdlib/doc/src/rand.xml
+++ b/lib/stdlib/doc/src/rand.xml
@@ -133,8 +133,9 @@
       variable <c>rand_seed</c> to remember the current state.</p>
 
     <p>If a process calls
-      <seealso marker="#uniform-0"><c>uniform/0</c></seealso> or
-      <seealso marker="#uniform-1"><c>uniform/1</c></seealso> without
+      <seealso marker="#uniform-0"><c>uniform/0</c></seealso>,
+      <seealso marker="#uniform-1"><c>uniform/1</c></seealso> or
+      <seealso marker="#uniform_real-0"><c>uniform_real/0</c></seealso> without
       setting a seed first, <seealso marker="#seed-1"><c>seed/1</c></seealso>
       is called automatically with the default algorithm and creates a
       non-constant seed.</p>
@@ -168,10 +169,17 @@ R3 = rand:uniform(),</pre>
 S0 = rand:seed_s(exrop),
 {R4, S1} = rand:uniform_s(S0),</pre>
 
+   <p>Textbook basic form Box-Muller standard normal deviate</p>
+
+   <pre>
+R5 = rand:uniform_real(),
+R6 = rand:uniform(),
+SND0 = math:sqrt(-2 * math:log(R5)) * math:cos(math:pi() * R6)</pre>
+
    <p>Create a standard normal deviate:</p>
 
    <pre>
-{SND0, S2} = rand:normal_s(S1),</pre>
+{SND1, S2} = rand:normal_s(S1),</pre>
 
    <p>Create a normal deviate with mean -3 and variance 0.5:</p>
 
@@ -414,7 +422,8 @@ tests. We suggest to use a sign test to extract a random Boolean value.</pre>
 	    This function may return exactly <c>0.0</c> which can be
 	    fatal for certain applications.  If that is undesired
 	    you can use <c>(1.0 - rand:uniform())</c> to get the
-	    interval <c>0.0 &lt; <anno>X</anno> =&lt; 1.0</c>.
+	    interval <c>0.0 &lt; <anno>X</anno> =&lt; 1.0</c>, or instead use
+	    <seealso marker="#uniform_real-0"><c>uniform_real/0</c></seealso>.
 	  </p>
 	  <p>
 	    If neither endpoint is desired you can test and re-try
@@ -432,6 +441,42 @@ end.</pre>
     </func>
 
     <func>
+      <name name="uniform_real" arity="0"/>
+      <fsummary>Return a random float.</fsummary>
+      <desc><marker id="uniform_real-0"/>
+        <p>
+	  Returns a random float
+	  uniformly distributed in the value range
+	  <c>DBL_MIN =&lt; <anno>X</anno> &lt; 1.0</c>
+	  and updates the state in the process dictionary.
+	</p>
+	<p>
+	  Conceptually, a random real number <c>R</c> is generated
+	  from the interval <c>0 =&lt; R &lt; 1</c> and then the
+	  closest rounded down normalized number
+	  in the IEEE 754 Double precision format
+	  is returned.
+	</p>
+	<note>
+	  <p>
+	    The generated numbers from this function has got better
+	    granularity for small numbers than the regular
+	    <seealso marker="#uniform-0"><c>uniform/0</c></seealso>
+	    because all bits in the mantissa are random.
+	    This property, in combination with the fact that exactly zero
+	    is never returned is useful for algoritms doing for example
+	    <c>1.0 / <anno>X</anno></c> or <c>math:log(<anno>X</anno>)</c>.
+	  </p>
+	</note>
+	<p>
+	  See
+	  <seealso marker="#uniform_real_s-1"><c>uniform_real_s/1</c></seealso>
+	  for more explanation.
+	</p>
+      </desc>
+    </func>
+
+    <func>
       <name name="uniform" arity="1"/>
       <fsummary>Return a random integer.</fsummary>
       <desc><marker id="uniform-1"/>
@@ -460,7 +505,8 @@ end.</pre>
 	    This function may return exactly <c>0.0</c> which can be
 	    fatal for certain applications.  If that is undesired
 	    you can use <c>(1.0 - rand:uniform(State))</c> to get the
-	    interval <c>0.0 &lt; <anno>X</anno> =&lt; 1.0</c>.
+	    interval <c>0.0 &lt; <anno>X</anno> =&lt; 1.0</c>, or instead use
+	    <seealso marker="#uniform_real_s-1"><c>uniform_real_s/1</c></seealso>.
 	  </p>
 	  <p>
 	    If neither endpoint is desired you can test and re-try
@@ -478,6 +524,68 @@ end.</pre>
     </func>
 
     <func>
+      <name name="uniform_real_s" arity="1"/>
+      <fsummary>Return a random float.</fsummary>
+      <desc>
+        <p>
+	  Returns, for a specified state, a random float
+	  uniformly distributed in the value range
+	  <c>DBL_MIN =&lt; <anno>X</anno> &lt; 1.0</c>
+	  and updates the state in the process dictionary.
+	</p>
+	<p>
+	  Conceptually, a random real number <c>R</c> is generated
+	  from the interval <c>0 =&lt; R &lt; 1</c> and then the
+	  closest rounded down normalized number
+	  in the IEEE 754 Double precision format
+	  is returned.
+	</p>
+	<note>
+	  <p>
+	    The generated numbers from this function has got better
+	    granularity for small numbers than the regular
+	    <seealso marker="#uniform_s-1"><c>uniform_s/1</c></seealso>
+	    because all bits in the mantissa are random.
+	    This property, in combination with the fact that exactly zero
+	    is never returned is useful for algoritms doing for example
+	    <c>1.0 / <anno>X</anno></c> or <c>math:log(<anno>X</anno>)</c>.
+	  </p>
+	</note>
+	<p>
+	  The concept implicates that the probability to get
+	  exactly zero is extremely low; so low that this function
+	  is in fact guaranteed to never return zero.  The smallest
+	  number that it might return is <c>DBL_MIN</c>, which is
+	  2.0^(-1022).
+	</p>
+	<p>
+	  The value range stated at the top of this function
+	  description is technically correct, but
+	  <c>0.0 =&lt; <anno>X</anno> &lt; 1.0</c>
+	  is a better description of the generated numbers'
+	  statistical distribution.  Except that exactly 0.0
+	  is never returned, which is not possible to observe
+	  statistically.
+	</p>
+	<p>
+	  For example; for all sub ranges
+	  <c>N*2.0^(-53) =&lt; X &lt; (N+1)*2.0^(-53)</c>
+	  where
+	  <c>0 =&lt; integer(N) &lt; 2.0^53</c>
+	  the probability is the same.
+	  Compare that with the form of the numbers generated by
+	  <seealso marker="#uniform_s-1"><c>uniform_s/1</c></seealso>.
+	</p>
+	<p>
+	  Having to generate extra random bits for
+	  small numbers costs a little performance.
+	  This function is about 20% slower than the regular
+	  <seealso marker="#uniform_s-1"><c>uniform_s/1</c></seealso>
+	</p>
+      </desc>
+    </func>
+
+    <func>
       <name name="uniform_s" arity="2"/>
       <fsummary>Return a random integer.</fsummary>
       <desc>
diff --git a/lib/stdlib/doc/src/ref_man.xml b/lib/stdlib/doc/src/ref_man.xml
index 878a3babc5..68bfddbc71 100644
--- a/lib/stdlib/doc/src/ref_man.xml
+++ b/lib/stdlib/doc/src/ref_man.xml
@@ -93,6 +93,7 @@
   <xi:include href="sys.xml"/>
   <xi:include href="timer.xml"/>
   <xi:include href="unicode.xml"/>
+  <xi:include href="uri_string.xml"/>
   <xi:include href="win32reg.xml"/>
   <xi:include href="zip.xml"/>
 </application>
diff --git a/lib/stdlib/doc/src/specs.xml b/lib/stdlib/doc/src/specs.xml
index 45b207b13d..d559adf9b6 100644
--- a/lib/stdlib/doc/src/specs.xml
+++ b/lib/stdlib/doc/src/specs.xml
@@ -60,6 +60,7 @@
   <xi:include href="../specs/specs_sys.xml"/>
   <xi:include href="../specs/specs_timer.xml"/>
   <xi:include href="../specs/specs_unicode.xml"/>
+  <xi:include href="../specs/specs_uri_string.xml"/>
   <xi:include href="../specs/specs_win32reg.xml"/>
   <xi:include href="../specs/specs_zip.xml"/>
 </specs>
diff --git a/lib/stdlib/doc/src/string.xml b/lib/stdlib/doc/src/string.xml
index 9d5edd9ecf..130fc74a28 100644
--- a/lib/stdlib/doc/src/string.xml
+++ b/lib/stdlib/doc/src/string.xml
@@ -109,10 +109,8 @@
     <p>This module has been reworked in Erlang/OTP 20 to
     handle <seealso marker="unicode#type-chardata">
     <c>unicode:chardata()</c></seealso> and operate on grapheme
-    clusters. The <seealso marker="#oldapi"> <c>old
-    functions</c></seealso> that only work on Latin-1 lists as input
-    are still available but should not be
-    used. They will be deprecated in Erlang/OTP 21.
+    clusters. The <c>old functions</c> that only work on Latin-1 lists as input
+    are kept for backwards compatibility reasons but should not be used.
     </p>
   </description>
 
@@ -594,7 +592,7 @@ ÖÄÅ</pre>
 	  or <c>both</c>, indicates from which direction characters
 	  are to be removed.
 	</p>
-	<p> Default <c><anno>Characters</anno></c> are the set of
+	<p> Default <c><anno>Characters</anno></c> is the set of
 	nonbreakable whitespace codepoints, defined as
 	Pattern_White_Space in
 	<url href="http://unicode.org/reports/tr31/">Unicode Standard Annex #31</url>.
@@ -631,393 +629,5 @@ ÖÄÅ</pre>
     </func>
 
   </funcs>
-
-  <section>
-    <marker id="oldapi"/>
-    <title>Obsolete API functions</title>
-    <p>Here follows the function of the old API.
-    These functions only work on a list of Latin-1 characters.
-    </p>
-    <note><p>
-      The functions are kept for backward compatibility, but are
-      not recommended.
-      They will be deprecated in Erlang/OTP 21.
-    </p>
-    <p>Any undocumented functions in <c>string</c> are not to be used.</p>
-    </note>
-  </section>
-
-  <funcs>
-    <func>
-      <name name="centre" arity="2"/>
-      <name name="centre" arity="3"/>
-      <fsummary>Center a string.</fsummary>
-      <desc>
-        <p>Returns a string, where <c><anno>String</anno></c> is centered in the
-          string and surrounded by blanks or <c><anno>Character</anno></c>.
-	  The resulting string has length <c><anno>Number</anno></c>.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#pad/3"><c>pad/3</c></seealso>.
-	</p>
-      </desc>
-    </func>
-
-    <func>
-      <name name="chars" arity="2"/>
-      <name name="chars" arity="3"/>
-      <fsummary>Return a string consisting of numbers of characters.</fsummary>
-      <desc>
-        <p>Returns a string consisting of <c><anno>Number</anno></c> characters
-          <c><anno>Character</anno></c>. Optionally, the string can end with
-          string <c><anno>Tail</anno></c>.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="lists#duplicate/2"><c>lists:duplicate/2</c></seealso>.</p>
-      </desc>
-    </func>
-
-    <func>
-      <name name="chr" arity="2"/>
-      <fsummary>Return the index of the first occurrence of
-        a character in a string.</fsummary>
-      <desc>
-        <p>Returns the index of the first occurrence of
-          <c><anno>Character</anno></c> in <c><anno>String</anno></c>. Returns
-          <c>0</c> if <c><anno>Character</anno></c> does not occur.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#find/2"><c>find/2</c></seealso>.</p>
-      </desc>
-    </func>
-
-    <func>
-      <name name="concat" arity="2"/>
-      <fsummary>Concatenate two strings.</fsummary>
-      <desc>
-        <p>Concatenates <c><anno>String1</anno></c> and
-          <c><anno>String2</anno></c> to form a new string
-          <c><anno>String3</anno></c>, which is returned.</p>
-	<p>
-	  This function is <seealso marker="#oldapi">obsolete</seealso>.
-	  Use <c>[<anno>String1</anno>, <anno>String2</anno>]</c> as
-	  <c>Data</c> argument, and call
-	  <seealso marker="unicode#characters_to_list/2">
-	  <c>unicode:characters_to_list/2</c></seealso> or
-	  <seealso marker="unicode#characters_to_binary/2">
-	  <c>unicode:characters_to_binary/2</c></seealso>
-	  to flatten the output.
-	</p>
-      </desc>
-    </func>
-
-    <func>
-      <name name="copies" arity="2"/>
-      <fsummary>Copy a string.</fsummary>
-      <desc>
-        <p>Returns a string containing <c><anno>String</anno></c> repeated
-          <c><anno>Number</anno></c> times.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="lists#duplicate/2"><c>lists:duplicate/2</c></seealso>.</p>
-      </desc>
-    </func>
-
-    <func>
-      <name name="cspan" arity="2"/>
-      <fsummary>Span characters at start of a string.</fsummary>
-      <desc>
-        <p>Returns the length of the maximum initial segment of
-          <c><anno>String</anno></c>, which consists entirely of characters
-          not from <c><anno>Chars</anno></c>.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#take/3"><c>take/3</c></seealso>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-> string:cspan("\t    abcdef", " \t").
-0</code>
-      </desc>
-    </func>
-
-    <func>
-      <name name="join" arity="2"/>
-      <fsummary>Join a list of strings with separator.</fsummary>
-      <desc>
-        <p>Returns a string with the elements of <c><anno>StringList</anno></c>
-          separated by the string in <c><anno>Separator</anno></c>.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="lists#join/2"><c>lists:join/2</c></seealso>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-> join(["one", "two", "three"], ", ").
-"one, two, three"</code>
-      </desc>
-    </func>
-
-    <func>
-      <name name="left" arity="2"/>
-      <name name="left" arity="3"/>
-      <fsummary>Adjust left end of a string.</fsummary>
-      <desc>
-        <p>Returns <c><anno>String</anno></c> with the length adjusted in
-          accordance with <c><anno>Number</anno></c>. The left margin is
-          fixed. If <c>length(<anno>String</anno>)</c> &lt;
-          <c><anno>Number</anno></c>, then <c><anno>String</anno></c> is padded
-          with blanks or <c><anno>Character</anno></c>s.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#pad/2"><c>pad/2</c></seealso> or
-	<seealso marker="#pad/3"><c>pad/3</c></seealso>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-> string:left("Hello",10,$.).
-"Hello....."</code>
-      </desc>
-    </func>
-
-    <func>
-      <name name="len" arity="1"/>
-      <fsummary>Return the length of a string.</fsummary>
-      <desc>
-        <p>Returns the number of characters in <c><anno>String</anno></c>.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#length/1"><c>length/1</c></seealso>.</p>
-      </desc>
-    </func>
-
-    <func>
-      <name name="rchr" arity="2"/>
-      <fsummary>Return the index of the last occurrence of
-        a character in a string.</fsummary>
-      <desc>
-        <p>Returns the index of the last occurrence of
-          <c><anno>Character</anno></c> in <c><anno>String</anno></c>. Returns
-          <c>0</c> if <c><anno>Character</anno></c> does not occur.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#find/3"><c>find/3</c></seealso>.</p>
-      </desc>
-    </func>
-
-    <func>
-      <name name="right" arity="2"/>
-      <name name="right" arity="3"/>
-      <fsummary>Adjust right end of a string.</fsummary>
-      <desc>
-        <p>Returns <c><anno>String</anno></c> with the length adjusted in
-          accordance with <c><anno>Number</anno></c>. The right margin is
-          fixed. If the length of <c>(<anno>String</anno>)</c> &lt;
-          <c><anno>Number</anno></c>, then <c><anno>String</anno></c> is padded
-          with blanks or <c><anno>Character</anno></c>s.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#pad/3"><c>pad/3</c></seealso>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-> string:right("Hello", 10, $.).
-".....Hello"</code>
-      </desc>
-    </func>
-
-    <func>
-      <name name="rstr" arity="2"/>
-      <fsummary>Find the index of a substring.</fsummary>
-      <desc>
-        <p>Returns the position where the last occurrence of
-          <c><anno>SubString</anno></c> begins in <c><anno>String</anno></c>.
-          Returns <c>0</c> if <c><anno>SubString</anno></c>
-          does not exist in <c><anno>String</anno></c>.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#find/3"><c>find/3</c></seealso>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-> string:rstr(" Hello Hello World World ", "Hello World").
-8</code>
-      </desc>
-    </func>
-
-    <func>
-      <name name="span" arity="2"/>
-      <fsummary>Span characters at start of a string.</fsummary>
-      <desc>
-        <p>Returns the length of the maximum initial segment of
-          <c><anno>String</anno></c>, which consists entirely of characters
-          from <c><anno>Chars</anno></c>.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#take/2"><c>take/2</c></seealso>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-> string:span("\t    abcdef", " \t").
-5</code>
-      </desc>
-    </func>
-
-    <func>
-      <name name="str" arity="2"/>
-      <fsummary>Find the index of a substring.</fsummary>
-      <desc>
-        <p>Returns the position where the first occurrence of
-          <c><anno>SubString</anno></c> begins in <c><anno>String</anno></c>.
-          Returns <c>0</c> if <c><anno>SubString</anno></c>
-          does not exist in <c><anno>String</anno></c>.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#find/2"><c>find/2</c></seealso>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-> string:str(" Hello Hello World World ", "Hello World").
-8</code>
-      </desc>
-    </func>
-
-    <func>
-      <name name="strip" arity="1"/>
-      <name name="strip" arity="2"/>
-      <name name="strip" arity="3"/>
-      <fsummary>Strip leading or trailing characters.</fsummary>
-      <desc>
-        <p>Returns a string, where leading or trailing, or both, blanks or a
-          number of <c><anno>Character</anno></c> have been removed.
-          <c><anno>Direction</anno></c>, which can be <c>left</c>, <c>right</c>,
-          or <c>both</c>, indicates from which direction blanks are to be
-          removed. <c>strip/1</c> is equivalent to
-          <c>strip(String, both)</c>.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#trim/3"><c>trim/3</c></seealso>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-> string:strip("...Hello.....", both, $.).
-"Hello"</code>
-      </desc>
-    </func>
-
-    <func>
-      <name name="sub_string" arity="2"/>
-      <name name="sub_string" arity="3"/>
-      <fsummary>Extract a substring.</fsummary>
-      <desc>
-        <p>Returns a substring of <c><anno>String</anno></c>, starting at
-          position <c><anno>Start</anno></c> to the end of the string, or to
-          and including position <c><anno>Stop</anno></c>.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#slice/3"><c>slice/3</c></seealso>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-sub_string("Hello World", 4, 8).
-"lo Wo"</code>
-      </desc>
-    </func>
-
-    <func>
-      <name name="substr" arity="2"/>
-      <name name="substr" arity="3"/>
-      <fsummary>Return a substring of a string.</fsummary>
-      <desc>
-        <p>Returns a substring of <c><anno>String</anno></c>, starting at
-          position <c><anno>Start</anno></c>, and ending at the end of the
-          string or at length <c><anno>Length</anno></c>.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#slice/3"><c>slice/3</c></seealso>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-> substr("Hello World", 4, 5).
-"lo Wo"</code>
-      </desc>
-    </func>
-
-    <func>
-      <name name="sub_word" arity="2"/>
-      <name name="sub_word" arity="3"/>
-      <fsummary>Extract subword.</fsummary>
-      <desc>
-        <p>Returns the word in position <c><anno>Number</anno></c> of
-          <c><anno>String</anno></c>. Words are separated by blanks or
-          <c><anno>Character</anno></c>s.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#nth_lexeme/3"><c>nth_lexeme/3</c></seealso>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-> string:sub_word(" Hello old boy !",3,$o).
-"ld b"</code>
-      </desc>
-    </func>
-
-    <func>
-      <name name="to_lower" arity="1" clause_i="1"/>
-      <name name="to_lower" arity="1" clause_i="2"/>
-      <name name="to_upper" arity="1" clause_i="1"/>
-      <name name="to_upper" arity="1" clause_i="2"/>
-      <fsummary>Convert case of string (ISO/IEC 8859-1).</fsummary>
-      <type variable="String" name_i="1"/>
-      <type variable="Result" name_i="1"/>
-      <type variable="Char"/>
-      <type variable="CharResult"/>
-      <desc>
-        <p>The specified string or character is case-converted. Notice that
-          the supported character set is ISO/IEC 8859-1 (also called Latin 1);
-          all values outside this set are unchanged</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso> use
-	<seealso marker="#lowercase/1"><c>lowercase/1</c></seealso>,
-	<seealso marker="#uppercase/1"><c>uppercase/1</c></seealso>,
-	<seealso marker="#titlecase/1"><c>titlecase/1</c></seealso> or
-	<seealso marker="#casefold/1"><c>casefold/1</c></seealso>.</p>
-      </desc>
-    </func>
-
-    <func>
-      <name name="tokens" arity="2"/>
-      <fsummary>Split string into tokens.</fsummary>
-      <desc>
-        <p>Returns a list of tokens in <c><anno>String</anno></c>, separated
-          by the characters in <c><anno>SeparatorList</anno></c>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-> tokens("abc defxxghix jkl", "x ").
-["abc", "def", "ghi", "jkl"]</code>
-        <p>Notice that, as shown in this example, two or more
-          adjacent separator characters in <c><anno>String</anno></c>
-          are treated as one. That is, there are no empty
-          strings in the resulting list of tokens.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#lexemes/2"><c>lexemes/2</c></seealso>.</p>
-      </desc>
-    </func>
-
-    <func>
-      <name name="words" arity="1"/>
-      <name name="words" arity="2"/>
-      <fsummary>Count blank separated words.</fsummary>
-      <desc>
-        <p>Returns the number of words in <c><anno>String</anno></c>, separated
-          by blanks or <c><anno>Character</anno></c>.</p>
-	<p>This function is <seealso marker="#oldapi">obsolete</seealso>.
-	Use
-	<seealso marker="#lexemes/2"><c>lexemes/2</c></seealso>.</p>
-        <p><em>Example:</em></p>
-        <code type="none">
-> words(" Hello old boy!", $o).
-4</code>
-      </desc>
-    </func>
-  </funcs>
-
-  <section>
-    <title>Notes</title>
-    <p>Some of the general string functions can seem to overlap each
-      other. The reason is that this string package is the
-      combination of two earlier packages and all functions of
-      both packages have been retained.</p>
-  </section>
-
 </erlref>
 
diff --git a/lib/stdlib/doc/src/unicode_usage.xml b/lib/stdlib/doc/src/unicode_usage.xml
index 26dc46719e..789e063c12 100644
--- a/lib/stdlib/doc/src/unicode_usage.xml
+++ b/lib/stdlib/doc/src/unicode_usage.xml
@@ -719,8 +719,8 @@ Eshell V5.10.1  (abort with ^G)
   </section> 
 
   <section>
-    <title>Unicode Filenames</title>
     <marker id="unicode_file_names"/>
+    <title>Unicode Filenames</title>
     <p>Most modern operating systems support Unicode filenames in some way.
       There are many different ways to do this and Erlang by default treats the
       different approaches differently:</p>
@@ -855,8 +855,12 @@ Eshell V5.10.1  (abort with ^G)
     </note>
 
     <section>
-      <title>Notes About Raw Filenames</title>
       <marker id="notes-about-raw-filenames"/>
+      <title>Notes About Raw Filenames</title>
+      <note><p>
+	Note that raw filenames <em>not</em> necessarily are encoded the
+	same way as on the OS level.
+      </p></note>
       <p>Raw filenames were introduced together with Unicode filename support
         in ERTS 5.8.2 (Erlang/OTP R14B01). The reason &quot;raw
         filenames&quot; were introduced in the system was
diff --git a/lib/stdlib/doc/src/uri_string.xml b/lib/stdlib/doc/src/uri_string.xml
new file mode 100644
index 0000000000..21f470e763
--- /dev/null
+++ b/lib/stdlib/doc/src/uri_string.xml
@@ -0,0 +1,326 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<!DOCTYPE erlref SYSTEM "erlref.dtd">
+
+<erlref>
+  <header>
+    <copyright>
+      <year>2017</year><year>2017</year>
+      <holder>Ericsson AB. All Rights Reserved.</holder>
+    </copyright>
+    <legalnotice>
+      Licensed under the Apache License, Version 2.0 (the "License");
+      you may not use this file except in compliance with the License.
+      You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+      Unless required by applicable law or agreed to in writing, software
+      distributed under the License is distributed on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+      See the License for the specific language governing permissions and
+      limitations under the License.
+    </legalnotice>
+
+    <title>uri_string</title>
+    <prepared>Péter Dimitrov</prepared>
+    <docno>1</docno>
+    <date>2017-10-24</date>
+    <rev>A</rev>
+  </header>
+  <module>uri_string</module>
+  <modulesummary>URI processing functions.</modulesummary>
+  <description>
+    <p>This module contains functions for parsing and handling URIs
+    (<url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url>) and
+    form-urlencoded query strings (<url href="https://www.w3.org/TR/html5/forms.html">HTML5</url>).
+    </p>
+    <p>A URI is an identifier consisting of a sequence of characters   matching the syntax
+    rule named <em>URI</em> in <url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url>.
+    </p>
+    <p>  The generic URI syntax consists of a hierarchical sequence of components referred
+    to as the scheme, authority, path, query, and fragment:</p>
+    <pre>
+    URI         = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
+    hier-part   = "//" authority path-abempty
+                   / path-absolute
+                   / path-rootless
+                   / path-empty
+    scheme      = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
+    authority   = [ userinfo "@" ] host [ ":" port ]
+    userinfo    = *( unreserved / pct-encoded / sub-delims / ":" )
+
+    reserved    = gen-delims / sub-delims
+    gen-delims  = ":" / "/" / "?" / "#" / "[" / "]" / "@"
+    sub-delims  = "!" / "$" / "&amp;" / "'" / "(" / ")"
+                / "*" / "+" / "," / ";" / "="
+
+    unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"
+    </pre><br></br>
+    <p>The interpretation of a URI depends only on the characters used and not on how those
+    characters are represented in a network protocol.</p>
+    <p>The functions implemented by this module cover the following use cases:</p>
+    <list type="bulleted">
+      <item>Parsing URIs into its components and returing a map<br></br>
+      <seealso marker="#parse/1"><c>parse/1</c></seealso>
+      </item>
+      <item>Recomposing a map of URI components into a URI string<br></br>
+      <seealso marker="#recompose/1"><c>recompose/1</c></seealso>
+      </item>
+      <item>Changing inbound binary and percent-encoding of URIs<br></br>
+      <seealso marker="#transcode/2"><c>transcode/2</c></seealso>
+      </item>
+      <item>Transforming URIs into a normalized form<br></br>
+      <seealso marker="#normalize/1"><c>normalize/1</c></seealso>
+      </item>
+      <item>Composing form-urlencoded query strings from a list of key-value pairs<br></br>
+      <seealso marker="#compose_query/1"><c>compose_query/1</c></seealso><br></br>
+      <seealso marker="#compose_query/2"><c>compose_query/2</c></seealso>
+      </item>
+      <item>Dissecting form-urlencoded query strings into a list of key-value pairs<br></br>
+      <seealso marker="#dissect_query/1"><c>dissect_query/1</c></seealso>
+      </item>
+    </list>
+    <p>There are four different encodings present during the handling of URIs:</p>
+    <list type="bulleted">
+      <item>Inbound binary encoding in binaries</item>
+      <item>Inbound percent-encoding in lists and binaries</item>
+      <item>Outbound binary encoding in binaries</item>
+      <item>Outbound percent-encoding in lists and binaries</item>
+    </list>
+    <p>Functions with <c>uri_string()</c> argument accept lists, binaries and
+    mixed lists (lists with binary elements) as input type. All of the functions but
+    <c>transcode/2</c> expects input as lists of unicode codepoints, UTF-8 encoded binaries
+    and UTF-8 percent-encoded URI parts ("%C3%B6" corresponds to the unicode character "ö").</p>
+    <p>Unless otherwise specified the return value type and encoding are the same as the input
+    type and encoding. That is, binary input returns binary output, list input returns a list
+    output but mixed input returns list output.</p>
+    <p>In case of lists there is only percent-encoding. In binaries, however, both binary encoding
+    and percent-encoding shall be considered. <c>transcode/2</c> provides the means to convert
+    between the supported encodings, it takes a <c>uri_string()</c> and a list of options
+    specifying inbound and outbound encodings.</p>
+    <p><url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url> does not mandate any specific
+    character encoding and it is usually defined by the protocol or surrounding text. This library
+    takes the same assumption, binary and percent-encoding are handled as one configuration unit,
+    they cannot be set to different values.</p>
+  </description>
+
+  <datatypes>
+    <datatype>
+      <name name="error"/>
+      <desc>
+        <p>Error tuple indicating the type of error. Possible values of the second component:</p>
+	<list type="bulleted">
+	  <item><c>invalid_character</c></item>
+	  <item><c>invalid_encoding</c></item>
+	  <item><c>invalid_input</c></item>
+	  <item><c>invalid_map</c></item>
+	  <item><c>invalid_percent_encoding</c></item>
+	  <item><c>invalid_scheme</c></item>
+	  <item><c>invalid_uri</c></item>
+	  <item><c>invalid_utf8</c></item>
+	  <item><c>missing_value</c></item>
+	</list>
+	<p>The third component is a term providing additional information about the
+	cause of the error.</p>
+      </desc>
+    </datatype>
+    <datatype>
+      <name name="uri_map"/>
+      <desc>
+        <p>Map holding the main components of a URI.</p>
+      </desc>
+    </datatype>
+    <datatype>
+      <name name="uri_string"/>
+      <desc>
+        <p>List of unicode codepoints, a UTF-8 encoded binary, or a mix of the two,
+        representing an <url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url>
+	compliant URI (<em>percent-encoded form</em>).
+        A URI is a sequence of characters from a very limited set: the letters of
+        the basic Latin alphabet, digits, and a few special characters.</p>
+      </desc>
+    </datatype>
+  </datatypes>
+
+  <funcs>
+
+    <func>
+      <name name="compose_query" arity="1"/>
+      <fsummary>Compose urlencoded query string.</fsummary>
+      <desc>
+        <p>Composes a form-urlencoded <c><anno>QueryString</anno></c> based on a
+	<c><anno>QueryList</anno></c>, a list of non-percent-encoded key-value pairs.
+        Form-urlencoding is defined in section
+	4.10.22.6 of the <url href="https://www.w3.org/TR/html5/forms.html">HTML5</url>
+	specification.
+	</p>
+	<p>See also the opposite operation <seealso marker="#dissect_query/1">
+	<c>dissect_query/1</c></seealso>.
+	</p>
+        <p><em>Example:</em></p>
+        <pre>
+1> <input>uri_string:compose_query([{"foo bar","1"},{"city","örebro"}]).</input>
+<![CDATA["foo+bar=1&city=%C3%B6rebro"]]>
+2> <![CDATA[uri_string:compose_query([{<<"foo bar">>,<<"1">>},
+2> {<<"city">>,<<"örebro"/utf8>>}]).]]>
+<![CDATA[<<"foo+bar=1&city=%C3%B6rebro">>]]>
+	</pre>
+      </desc>
+    </func>
+
+    <func>
+      <name name="compose_query" arity="2"/>
+      <fsummary>Compose urlencoded query string.</fsummary>
+      <desc>
+        <p>Same as <c>compose_query/1</c> but with an additional
+	<c><anno>Options</anno></c> parameter, that controls the encoding ("charset")
+	used by the encoding algorithm. There are two supported encodings: <c>utf8</c>
+	(or <c>unicode</c>) and <c>latin1</c>.
+	</p>
+	<p>Each character in the entry's name and value that cannot be expressed using
+	the selected character encoding, is replaced by a string consisting of a U+0026
+	AMPERSAND character (<![CDATA[&]]>), a "#" (U+0023) character, one or more ASCII
+	digits representing the Unicode code point of the character in base ten, and
+	finally	a ";" (U+003B) character.
+	</p>
+	<p>Bytes that are out of the range 0x2A, 0x2D, 0x2E, 0x30 to 0x39, 0x41 to 0x5A, 0x5F,
+	0x61 to 0x7A, are percent-encoded (U+0025 PERCENT SIGN character (%) followed by
+	uppercase ASCII hex digits representing the hexadecimal value of the byte).
+	</p>
+	<p>See also the opposite operation <seealso marker="#dissect_query/1">
+	<c>dissect_query/1</c></seealso>.
+	</p>
+        <p><em>Example:</em></p>
+        <pre>
+1> <input>uri_string:compose_query([{"foo bar","1"},{"city","örebro"}],</input>
+1> [{encoding, latin1}]).
+<![CDATA["foo+bar=1&city=%F6rebro"
+2> uri_string:compose_query([{<<"foo bar">>,<<"1">>},
+2> {<<"city">>,<<"東京"/utf8>>}], [{encoding, latin1}]).]]>
+<![CDATA[<<"foo+bar=1&city=%26%2326481%3B%26%2320140%3B">>]]>
+	</pre>
+      </desc>
+    </func>
+
+    <func>
+      <name name="dissect_query" arity="1"/>
+      <fsummary>Dissect query string.</fsummary>
+      <desc>
+        <p>Dissects an urlencoded <c><anno>QueryString</anno></c> and returns a
+	<c><anno>QueryList</anno></c>, a list of non-percent-encoded key-value pairs.
+        Form-urlencoding is defined in section
+	4.10.22.6 of the <url href="https://www.w3.org/TR/html5/forms.html">HTML5</url>
+	specification.
+	</p>
+	<p>It is not as strict for its input as the decoding algorithm defined by
+	<url href="https://www.w3.org/TR/html5/forms.html">HTML5</url>
+	and accepts all unicode characters.</p>
+	<p>See also the opposite operation <seealso marker="#compose_query/1">
+	<c>compose_query/1</c></seealso>.
+	</p>
+        <p><em>Example:</em></p>
+        <pre>
+1> <input><![CDATA[uri_string:dissect_query("foo+bar=1&city=%C3%B6rebro").]]></input>
+[{"foo bar","1"},{"city","örebro"}]
+2> <![CDATA[uri_string:dissect_query(<<"foo+bar=1&city=%26%2326481%3B%26%2320140%3B">>).]]>
+<![CDATA[[{<<"foo bar">>,<<"1">>},
+ {<<"city">>,<<230,157,177,228,186,172>>}] ]]>
+	</pre>
+      </desc>
+    </func>
+
+    <func>
+      <name name="normalize" arity="1"/>
+      <fsummary>Syntax-based normalization.</fsummary>
+      <desc>
+        <p>Transforms <c><anno>URIString</anno></c> into a normalized form
+	using Syntax-Based Normalization as defined by
+	<url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url>.</p>
+	<p>This function implements case normalization, percent-encoding
+	normalization, path segment normalization and scheme based normalization
+	for HTTP(S) with basic support for FTP, SSH, SFTP and TFTP.</p>
+        <p><em>Example:</em></p>
+        <pre>
+1> <input>uri_string:normalize("/a/b/c/./../../g").</input>
+"/a/g"
+2> <![CDATA[uri_string:normalize(<<"mid/content=5/../6">>).]]>
+<![CDATA[<<"mid/6">>]]>
+3> uri_string:normalize("http://localhost:80").
+"https://localhost/"
+	</pre>
+      </desc>
+    </func>
+
+    <func>
+      <name name="parse" arity="1"/>
+      <fsummary>Parse URI into a map.</fsummary>
+      <desc>
+        <p>Parses an <url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url>
+	compliant <c>uri_string()</c> into a <c>uri_map()</c>, that holds the parsed
+	components of the <c>URI</c>.
+	If parsing fails, an error tuple is returned.</p>
+	<p>See also the opposite operation <seealso marker="#recompose/1">
+	<c>recompose/1</c></seealso>.</p>
+        <p><em>Example:</em></p>
+        <pre>
+1> <input>uri_string:parse("foo://[email protected]:8042/over/there?name=ferret#nose").</input>
+#{fragment => "nose",host => "example.com",
+  path => "/over/there",port => 8042,query => "name=ferret",
+  scheme => foo,userinfo => "user"}
+2> <![CDATA[uri_string:parse(<<"foo://[email protected]:8042/over/there?name=ferret">>).]]>
+<![CDATA[#{host => <<"example.com">>,path => <<"/over/there">>,
+  port => 8042,query => <<"name=ferret">>,scheme => <<"foo">>,
+  userinfo => <<"user">>}]]>
+	</pre>
+      </desc>
+    </func>
+
+    <func>
+      <name name="recompose" arity="1"/>
+      <fsummary>Recompose URI.</fsummary>
+      <desc>
+        <p>Creates an <url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url> compliant
+	<c><anno>URIString</anno></c> (percent-encoded), based on the components of
+	<c><anno>URIMap</anno></c>.
+	If the <c><anno>URIMap</anno></c> is invalid, an error tuple is returned.</p>
+	<p>See also the opposite operation <seealso marker="#parse/1">
+	<c>parse/1</c></seealso>.</p>
+        <p><em>Example:</em></p>
+        <pre>
+1> <input>URIMap = #{fragment => "nose", host => "example.com", path => "/over/there",</input>
+1> port => 8042, query => "name=ferret", scheme => "foo", userinfo => "user"}.
+#{fragment => "top",host => "example.com",
+  path => "/over/there",port => 8042,query => "?name=ferret",
+  scheme => foo,userinfo => "user"}
+
+2> <input>uri_string:recompose(URIMap).</input>
+"foo://example.com:8042/over/there?name=ferret#nose"</pre>
+      </desc>
+    </func>
+
+    <func>
+      <name name="transcode" arity="2"/>
+      <fsummary>Transcode URI.</fsummary>
+      <desc>
+        <p>Transcodes an <url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url>
+	compliant <c><anno>URIString</anno></c>,
+	where <c><anno>Options</anno></c> is a list of tagged tuples, specifying the inbound
+	(<c>in_encoding</c>) and outbound (<c>out_encoding</c>) encodings. <c>in_encoding</c>
+	and <c>out_encoding</c> specifies both binary encoding and percent-encoding for the
+	input and output data. Mixed encoding, where binary encoding is not the same as
+	percent-encoding, is not supported.
+	If an argument is invalid, an error tuple is returned.</p>
+        <p><em>Example:</em></p>
+        <pre>
+1> <input><![CDATA[uri_string:transcode(<<"foo%00%00%00%F6bar"/utf32>>,]]></input>
+1> [{in_encoding, utf32},{out_encoding, utf8}]).
+<![CDATA[<<"foo%C3%B6bar"/utf8>>]]>
+2> uri_string:transcode("foo%F6bar", [{in_encoding, latin1},
+2> {out_encoding, utf8}]).
+"foo%C3%B6bar"
+	</pre>
+      </desc>
+    </func>
+
+  </funcs>
+</erlref>
diff --git a/lib/stdlib/src/Makefile b/lib/stdlib/src/Makefile
index bf836203ec..8b156929d7 100644
--- a/lib/stdlib/src/Makefile
+++ b/lib/stdlib/src/Makefile
@@ -121,6 +121,7 @@ MODULES= \
 	timer \
 	unicode \
 	unicode_util \
+	uri_string \
 	win32reg \
 	zip
 
diff --git a/lib/stdlib/src/base64.erl b/lib/stdlib/src/base64.erl
index 5885745fb1..6ea4147abf 100644
--- a/lib/stdlib/src/base64.erl
+++ b/lib/stdlib/src/base64.erl
@@ -24,22 +24,11 @@
 -export([encode/1, decode/1, mime_decode/1,
 	 encode_to_string/1, decode_to_string/1, mime_decode_to_string/1]).
 
-%%-------------------------------------------------------------------------
 %% The following type is a subtype of string() for return values
 %% of (some) functions of this module.
-%%-------------------------------------------------------------------------
-
 -type ascii_string() :: [1..255].
 -type ascii_binary() :: binary().
 
-%%-------------------------------------------------------------------------
-%% encode_to_string(ASCII) -> Base64String
-%%	ASCII - string() | binary()
-%%	Base64String - string()
-%%                                   
-%% Description: Encodes a plain ASCII string (or binary) into base64.
-%%-------------------------------------------------------------------------
-
 -spec encode_to_string(Data) -> Base64String when
       Data :: ascii_string() | ascii_binary(),
       Base64String :: ascii_string().
@@ -47,107 +36,89 @@
 encode_to_string(Bin) when is_binary(Bin) ->
     encode_to_string(binary_to_list(Bin));
 encode_to_string(List) when is_list(List) ->
-    encode_l(List).
-
-%%-------------------------------------------------------------------------
-%% encode(ASCII) -> Base64
-%%	ASCII - string() | binary()
-%%	Base64 - binary()
-%%                                   
-%% Description: Encodes a plain ASCII string (or binary) into base64.
-%%-------------------------------------------------------------------------
+    encode_list_to_string(List).
 
 -spec encode(Data) -> Base64 when
       Data :: ascii_string() | ascii_binary(),
       Base64 :: ascii_binary().
 
 encode(Bin) when is_binary(Bin) ->
-    encode_binary(Bin);
+    encode_binary(Bin, <<>>);
 encode(List) when is_list(List) ->
-    list_to_binary(encode_l(List)).
+    encode_list(List, <<>>).
 
--spec encode_l(ascii_string()) -> ascii_string().
-
-encode_l([]) ->
+encode_list_to_string([]) ->
     [];
-encode_l([A]) ->
-    [b64e(A bsr 2),
-     b64e((A band 3) bsl 4), $=, $=];
-encode_l([A,B]) ->
-    [b64e(A bsr 2),
-     b64e(((A band 3) bsl 4) bor (B bsr 4)), 
-     b64e((B band 15) bsl 2), $=];
-encode_l([A,B,C|Ls]) ->
-    BB = (A bsl 16) bor (B bsl 8) bor C,
+encode_list_to_string([B1]) ->
+    [b64e(B1 bsr 2),
+     b64e((B1 band 3) bsl 4), $=, $=];
+encode_list_to_string([B1,B2]) ->
+    [b64e(B1 bsr 2),
+     b64e(((B1 band 3) bsl 4) bor (B2 bsr 4)),
+     b64e((B2 band 15) bsl 2), $=];
+encode_list_to_string([B1,B2,B3|Ls]) ->
+    BB = (B1 bsl 16) bor (B2 bsl 8) bor B3,
     [b64e(BB bsr 18),
      b64e((BB bsr 12) band 63), 
      b64e((BB bsr 6) band 63),
-     b64e(BB band 63) | encode_l(Ls)].
-
-encode_binary(Bin) ->
-    Split = 3*(byte_size(Bin) div 3),
-    <<Main0:Split/binary,Rest/binary>> = Bin,
-    Main = << <<(b64e(C)):8>> || <<C:6>> <= Main0 >>,
-    case Rest of
-	<<A:6,B:6,C:4>> ->
-	    <<Main/binary,(b64e(A)):8,(b64e(B)):8,(b64e(C bsl 2)):8,$=:8>>;
-	<<A:6,B:2>> ->
-	    <<Main/binary,(b64e(A)):8,(b64e(B bsl 4)):8,$=:8,$=:8>>;
-	<<>> ->
-	    Main
-    end.
+     b64e(BB band 63) | encode_list_to_string(Ls)].
 
-%%-------------------------------------------------------------------------
-%% mime_decode(Base64) -> ASCII
-%% decode(Base64) -> ASCII
-%%	Base64 - string() | binary()
-%%	ASCII - binary()
-%%                                    
-%% Description: Decodes an base64 encoded string to plain ASCII.
-%% mime_decode strips away all characters not Base64 before converting,
-%% whereas decode crashes if an illegal character is found
-%%-------------------------------------------------------------------------
+encode_binary(<<>>, A) ->
+    A;
+encode_binary(<<B1:8>>, A) ->
+    <<A/bits,(b64e(B1 bsr 2)):8,(b64e((B1 band 3) bsl 4)):8,$=:8,$=:8>>;
+encode_binary(<<B1:8, B2:8>>, A) ->
+    <<A/bits,(b64e(B1 bsr 2)):8,
+      (b64e(((B1 band 3) bsl 4) bor (B2 bsr 4))):8,
+      (b64e((B2 band 15) bsl 2)):8, $=:8>>;
+encode_binary(<<B1:8, B2:8, B3:8, Ls/bits>>, A) ->
+    BB = (B1 bsl 16) bor (B2 bsl 8) bor B3,
+    encode_binary(Ls,
+                  <<A/bits,(b64e(BB bsr 18)):8,
+                    (b64e((BB bsr 12) band 63)):8,
+                    (b64e((BB bsr 6) band 63)):8,
+                    (b64e(BB band 63)):8>>).
+
+encode_list([], A) ->
+    A;
+encode_list([B1], A) ->
+    <<A/bits,(b64e(B1 bsr 2)):8,(b64e((B1 band 3) bsl 4)):8,$=:8,$=:8>>;
+encode_list([B1,B2], A) ->
+    <<A/bits,(b64e(B1 bsr 2)):8,
+      (b64e(((B1 band 3) bsl 4) bor (B2 bsr 4))):8,
+      (b64e((B2 band 15) bsl 2)):8, $=:8>>;
+encode_list([B1,B2,B3|Ls], A) ->
+    BB = (B1 bsl 16) bor (B2 bsl 8) bor B3,
+    encode_list(Ls,
+                <<A/bits,(b64e(BB bsr 18)):8,
+                  (b64e((BB bsr 12) band 63)):8,
+                  (b64e((BB bsr 6) band 63)):8,
+                  (b64e(BB band 63)):8>>).
+
+%% mime_decode strips away all characters not Base64 before
+%% converting, whereas decode crashes if an illegal character is found
 
 -spec decode(Base64) -> Data when
       Base64 :: ascii_string() | ascii_binary(),
       Data :: ascii_binary().
 
 decode(Bin) when is_binary(Bin) ->
-    decode_binary(<<>>, Bin);
+    decode_binary(Bin, <<>>);
 decode(List) when is_list(List) ->
-    list_to_binary(decode_l(List)).
+    decode_list(List, <<>>).
 
 -spec mime_decode(Base64) -> Data when
       Base64 :: ascii_string() | ascii_binary(),
       Data :: ascii_binary().
 
 mime_decode(Bin) when is_binary(Bin) ->
-    mime_decode_binary(<<>>, Bin);
+    mime_decode_binary(Bin, <<>>);
 mime_decode(List) when is_list(List) ->
-    mime_decode(list_to_binary(List)).
-
--spec decode_l(ascii_string()) -> ascii_string().
-
-decode_l(List) ->
-    L = strip_spaces(List, []),
-    decode(L, []).
-
--spec mime_decode_l(ascii_string()) -> ascii_string().
+    mime_decode_list(List, <<>>).
 
-mime_decode_l(List) ->
-    L = strip_illegal(List, [], 0),
-    decode(L, []).
-
-%%-------------------------------------------------------------------------
-%% mime_decode_to_string(Base64) -> ASCII
-%% decode_to_string(Base64) -> ASCII
-%%	Base64 - string() | binary()
-%%	ASCII - binary()
-%%
-%% Description: Decodes an base64 encoded string to plain ASCII.
-%% mime_decode strips away all characters not Base64 before converting,
-%% whereas decode crashes if an illegal character is found
-%%-------------------------------------------------------------------------
+%% mime_decode_to_string strips away all characters not Base64 before
+%% converting, whereas decode_to_string crashes if an illegal
+%% character is found
 
 -spec decode_to_string(Base64) -> DataString when
       Base64 :: ascii_string() | ascii_binary(),
@@ -156,7 +127,7 @@ mime_decode_l(List) ->
 decode_to_string(Bin) when is_binary(Bin) ->
     decode_to_string(binary_to_list(Bin));
 decode_to_string(List) when is_list(List) ->
-    decode_l(List).
+    decode_list_to_string(List).
 
 -spec mime_decode_to_string(Base64) -> DataString when
       Base64 :: ascii_string() | ascii_binary(),
@@ -165,202 +136,326 @@ decode_to_string(List) when is_list(List) ->
 mime_decode_to_string(Bin) when is_binary(Bin) ->
     mime_decode_to_string(binary_to_list(Bin));
 mime_decode_to_string(List) when is_list(List) ->
-    mime_decode_l(List).
-
-%% One-based decode map.
--define(DECODE_MAP,
-	{bad,bad,bad,bad,bad,bad,bad,bad,ws,ws,bad,bad,ws,bad,bad, %1-15
-	 bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad, %16-31
-	 ws,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,62,bad,bad,bad,63, %32-47
-	 52,53,54,55,56,57,58,59,60,61,bad,bad,bad,eq,bad,bad, %48-63
-	 bad,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,
-	 15,16,17,18,19,20,21,22,23,24,25,bad,bad,bad,bad,bad,
-	 bad,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,
-	 41,42,43,44,45,46,47,48,49,50,51,bad,bad,bad,bad,bad,
-	 bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
-	 bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
-	 bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
-	 bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
-	 bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
-	 bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
-	 bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
-	 bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad}).
-
-decode_binary(Result0, <<C:8,T0/bits>>) ->
-    case element(C, ?DECODE_MAP) of
-	bad ->
-	    erlang:error({badarg,C});
-	ws ->
-	    decode_binary(Result0, T0);
-	eq ->
-	    case strip_ws(T0) of
-		<<$=:8,T/binary>> ->
-		    <<>> = strip_ws(T),
-		    Split = byte_size(Result0) - 1,
-		    <<Result:Split/bytes,_:4>> = Result0,
-		    Result;
-		T ->
-		    <<>> = strip_ws(T),
-		    Split = byte_size(Result0) - 1,
-		    <<Result:Split/bytes,_:2>> = Result0,
-		    Result
-	    end;
-	Bits ->
-	    decode_binary(<<Result0/bits,Bits:6>>, T0)
-    end;
-decode_binary(Result, <<>>) ->
-    true = is_binary(Result),
-    Result.
+    mime_decode_list_to_string(List).
 
 %% Skipping pad character if not at end of string. Also liberal about
 %% excess padding and skipping of other illegal (non-base64 alphabet)
 %% characters. See section 3.3 of RFC4648
-mime_decode_binary(Result, <<0:8,T/bits>>) ->
-    mime_decode_binary(Result, T);
-mime_decode_binary(Result0, <<C:8,T/bits>>) ->
-    case element(C, ?DECODE_MAP) of
-        Bits when is_integer(Bits) ->
-            mime_decode_binary(<<Result0/bits,Bits:6>>, T);
+mime_decode_list([0 | Cs], A) ->
+    mime_decode_list(Cs, A);
+mime_decode_list([C1 | Cs], A) ->
+    case b64d(C1) of
+        B1 when is_integer(B1) -> mime_decode_list(Cs, A, B1);
+        _ -> mime_decode_list(Cs, A)  % eq is padding
+    end;
+mime_decode_list([], A) ->
+    A.
+
+mime_decode_list([0 | Cs], A, B1) ->
+    mime_decode_list(Cs, A, B1);
+mime_decode_list([C2 | Cs], A, B1) ->
+    case b64d(C2) of
+        B2 when is_integer(B2) ->
+            mime_decode_list(Cs, A, B1, B2);
+        _ -> mime_decode_list(Cs, A, B1) % eq is padding
+    end.
+
+mime_decode_list([0 | Cs], A, B1, B2) ->
+    mime_decode_list(Cs, A, B1, B2);
+mime_decode_list([C3 | Cs], A, B1, B2) ->
+    case b64d(C3) of
+        B3 when is_integer(B3) ->
+            mime_decode_list(Cs, A, B1, B2, B3);
+        eq=B3 ->
+            mime_decode_list_after_eq(Cs, A, B1, B2, B3);
+        _ -> mime_decode_list(Cs, A, B1, B2)
+    end.
+
+mime_decode_list([0 | Cs], A, B1, B2, B3) ->
+    mime_decode_list(Cs, A, B1, B2, B3);
+mime_decode_list([C4 | Cs], A, B1, B2, B3) ->
+    case b64d(C4) of
+        B4 when is_integer(B4) ->
+            mime_decode_list(Cs, <<A/bits,B1:6,B2:6,B3:6,B4:6>>);
         eq ->
-            mime_decode_binary_after_eq(Result0, T, false);
-        _ ->
-            mime_decode_binary(Result0, T)
+            mime_decode_list_after_eq(Cs, A, B1, B2, B3);
+        _ -> mime_decode_list(Cs, A, B1, B2, B3)
+    end.
+
+mime_decode_list_after_eq([0 | Cs], A, B1, B2, B3) ->
+    mime_decode_list_after_eq(Cs, A, B1, B2, B3);
+mime_decode_list_after_eq([C | Cs], A, B1, B2, B3) ->
+    case b64d(C) of
+        B when is_integer(B) ->
+            %% More valid data, skip the eq as invalid
+            case B3 of
+                eq -> mime_decode_list(Cs, A, B1, B2, B);
+                _ -> mime_decode_list(Cs, <<A/bits,B1:6,B2:6,B3:6,B:6>>)
+            end;
+        _ -> mime_decode_list_after_eq(Cs, A, B1, B2, B3)
     end;
-mime_decode_binary(Result, _) ->
-    true = is_binary(Result),
-    Result.
-
-mime_decode_binary_after_eq(Result, <<0:8,T/bits>>, Eq) ->
-    mime_decode_binary_after_eq(Result, T, Eq);
-mime_decode_binary_after_eq(Result0, <<C:8,T/bits>>, Eq) ->
-    case element(C, ?DECODE_MAP) of
-        bad ->
-            mime_decode_binary_after_eq(Result0, T, Eq);
-        ws ->
-            mime_decode_binary_after_eq(Result0, T, Eq);
+mime_decode_list_after_eq([], A, B1, B2, eq) ->
+    <<A/bits,B1:6,(B2 bsr 4):2>>;
+mime_decode_list_after_eq([], A, B1, B2, B3) ->
+    <<A/bits,B1:6,B2:6,(B3 bsr 2):4>>.
+
+mime_decode_binary(<<0:8, Cs/bits>>, A) ->
+    mime_decode_binary(Cs, A);
+mime_decode_binary(<<C1:8, Cs/bits>>, A) ->
+    case b64d(C1) of
+        B1 when is_integer(B1) -> mime_decode_binary(Cs, A, B1);
+        _ -> mime_decode_binary(Cs, A)  % eq is padding
+    end;
+mime_decode_binary(<<>>, A) ->
+    A.
+
+mime_decode_binary(<<0:8, Cs/bits>>, A, B1) ->
+    mime_decode_binary(Cs, A, B1);
+mime_decode_binary(<<C2:8, Cs/bits>>, A, B1) ->
+    case b64d(C2) of
+        B2 when is_integer(B2) ->
+            mime_decode_binary(Cs, A, B1, B2);
+        _ -> mime_decode_binary(Cs, A, B1) % eq is padding
+    end.
+
+mime_decode_binary(<<0:8, Cs/bits>>, A, B1, B2) ->
+    mime_decode_binary(Cs, A, B1, B2);
+mime_decode_binary(<<C3:8, Cs/bits>>, A, B1, B2) ->
+    case b64d(C3) of
+        B3 when is_integer(B3) ->
+            mime_decode_binary(Cs, A, B1, B2, B3);
+        eq=B3 ->
+            mime_decode_binary_after_eq(Cs, A, B1, B2, B3);
+        _ -> mime_decode_binary(Cs, A, B1, B2)
+    end.
+
+mime_decode_binary(<<0:8, Cs/bits>>, A, B1, B2, B3) ->
+    mime_decode_binary(Cs, A, B1, B2, B3);
+mime_decode_binary(<<C4:8, Cs/bits>>, A, B1, B2, B3) ->
+    case b64d(C4) of
+        B4 when is_integer(B4) ->
+            mime_decode_binary(Cs, <<A/bits,B1:6,B2:6,B3:6,B4:6>>);
         eq ->
-            mime_decode_binary_after_eq(Result0, T, true);
-        Bits when is_integer(Bits) ->
+            mime_decode_binary_after_eq(Cs, A, B1, B2, B3);
+        _ -> mime_decode_binary(Cs, A, B1, B2, B3)
+    end.
+
+mime_decode_binary_after_eq(<<0:8, Cs/bits>>, A, B1, B2, B3) ->
+    mime_decode_binary_after_eq(Cs, A, B1, B2, B3);
+mime_decode_binary_after_eq(<<C:8, Cs/bits>>, A, B1, B2, B3) ->
+    case b64d(C) of
+        B when is_integer(B) ->
             %% More valid data, skip the eq as invalid
-            mime_decode_binary(<<Result0/bits,Bits:6>>, T)
+            case B3 of
+                eq -> mime_decode_binary(Cs, A, B1, B2, B);
+                _ -> mime_decode_binary(Cs, <<A/bits,B1:6,B2:6,B3:6,B:6>>)
+            end;
+        _ -> mime_decode_binary_after_eq(Cs, A, B1, B2, B3)
+    end;
+mime_decode_binary_after_eq(<<>>, A, B1, B2, eq) ->
+    <<A/bits,B1:6,(B2 bsr 4):2>>;
+mime_decode_binary_after_eq(<<>>, A, B1, B2, B3) ->
+    <<A/bits,B1:6,B2:6,(B3 bsr 2):4>>.
+
+mime_decode_list_to_string([0 | Cs]) ->
+    mime_decode_list_to_string(Cs);
+mime_decode_list_to_string([C1 | Cs]) ->
+    case b64d(C1) of
+        B1 when is_integer(B1) -> mime_decode_list_to_string(Cs, B1);
+        _ -> mime_decode_list_to_string(Cs) % eq is padding
     end;
-mime_decode_binary_after_eq(Result0, <<>>, Eq) ->
-    %% No more valid data.
-    case bit_size(Result0) rem 8 of
-        0 ->
-            %% '====' is not uncommon.
-            Result0;
-        4 when Eq ->
-            %% enforce at least one more '=' only ignoring illegals and spacing
-            Split = byte_size(Result0) - 1,
-            <<Result:Split/bytes,_:4>> = Result0,
-            Result;
-        2 ->
-            %% remove 2 bits
-            Split = byte_size(Result0) - 1,
-            <<Result:Split/bytes,_:2>> = Result0,
-            Result
+mime_decode_list_to_string([]) ->
+    [].
+
+mime_decode_list_to_string([0 | Cs], B1) ->
+    mime_decode_list_to_string(Cs, B1);
+mime_decode_list_to_string([C2 | Cs], B1) ->
+    case b64d(C2) of
+        B2 when is_integer(B2) ->
+            mime_decode_list_to_string(Cs, B1, B2);
+        _ -> mime_decode_list_to_string(Cs, B1) % eq is padding
     end.
 
-decode([], A) -> A;
-decode([$=,$=,C2,C1|Cs], A) ->
-    Bits2x6 = (b64d(C1) bsl 18) bor (b64d(C2) bsl 12),
-    Octet1 = Bits2x6 bsr 16,
-    decode(Cs, [Octet1|A]);
-decode([$=,C3,C2,C1|Cs], A) ->
-    Bits3x6 = (b64d(C1) bsl 18) bor (b64d(C2) bsl 12)
-	bor (b64d(C3) bsl 6),
-    Octet1 = Bits3x6 bsr 16,
-    Octet2 = (Bits3x6 bsr 8) band 16#ff,
-    decode(Cs, [Octet1,Octet2|A]);
-decode([C4,C3,C2,C1| Cs], A) ->
-    Bits4x6 = (b64d(C1) bsl 18) bor (b64d(C2) bsl 12)
-	bor (b64d(C3) bsl 6) bor b64d(C4),
-    Octet1 = Bits4x6 bsr 16,
-    Octet2 = (Bits4x6 bsr 8) band 16#ff,
-    Octet3 = Bits4x6 band 16#ff,
-    decode(Cs, [Octet1,Octet2,Octet3|A]).
+mime_decode_list_to_string([0 | Cs], B1, B2) ->
+    mime_decode_list_to_string(Cs, B1, B2);
+mime_decode_list_to_string([C3 | Cs], B1, B2) ->
+    case b64d(C3) of
+        B3 when is_integer(B3) ->
+            mime_decode_list_to_string(Cs, B1, B2, B3);
+        eq=B3 -> mime_decode_list_to_string_after_eq(Cs, B1, B2, B3);
+        _ -> mime_decode_list_to_string(Cs, B1, B2)
+    end.
 
-%%%========================================================================
-%%% Internal functions
-%%%========================================================================
+mime_decode_list_to_string([0 | Cs], B1, B2, B3) ->
+    mime_decode_list_to_string(Cs, B1, B2, B3);
+mime_decode_list_to_string([C4 | Cs], B1, B2, B3) ->
+    case b64d(C4) of
+        B4 when is_integer(B4) ->
+            Bits4x6 = (B1 bsl 18) bor (B2 bsl 12) bor (B3 bsl 6) bor B4,
+            Octet1 = Bits4x6 bsr 16,
+            Octet2 = (Bits4x6 bsr 8) band 16#ff,
+            Octet3 = Bits4x6 band 16#ff,
+            [Octet1, Octet2, Octet3 | mime_decode_list_to_string(Cs)];
+        eq ->
+            mime_decode_list_to_string_after_eq(Cs, B1, B2, B3);
+        _ -> mime_decode_list_to_string(Cs, B1, B2, B3)
+    end.
 
-strip_spaces([], A) -> A;
-strip_spaces([$\s|Cs], A) -> strip_spaces(Cs, A);
-strip_spaces([$\t|Cs], A) -> strip_spaces(Cs, A);
-strip_spaces([$\r|Cs], A) -> strip_spaces(Cs, A);
-strip_spaces([$\n|Cs], A) -> strip_spaces(Cs, A);
-strip_spaces([C|Cs], A) -> strip_spaces(Cs, [C | A]).
-
-strip_ws(<<$\t,T/binary>>) ->
-    strip_ws(T);
-strip_ws(<<$\n,T/binary>>) ->
-    strip_ws(T);
-strip_ws(<<$\r,T/binary>>) ->
-    strip_ws(T);
-strip_ws(<<$\s,T/binary>>) ->
-    strip_ws(T);
-strip_ws(T) -> T.
+mime_decode_list_to_string_after_eq([0 | Cs], B1, B2, B3) ->
+    mime_decode_list_to_string_after_eq(Cs, B1, B2, B3);
+mime_decode_list_to_string_after_eq([C | Cs], B1, B2, B3) ->
+    case b64d(C) of
+        B when is_integer(B) ->
+            %% More valid data, skip the eq as invalid
+            case B3 of
+                eq -> mime_decode_list_to_string(Cs, B1, B2, B);
+                _ ->
+                    Bits4x6 = (B1 bsl 18) bor (B2 bsl 12) bor (B3 bsl 6) bor B,
+                    Octet1 = Bits4x6 bsr 16,
+                    Octet2 = (Bits4x6 bsr 8) band 16#ff,
+                    Octet3 = Bits4x6 band 16#ff,
+                    [Octet1, Octet2, Octet3 | mime_decode_list_to_string(Cs)]
+            end;
+        _ -> mime_decode_list_to_string_after_eq(Cs, B1, B2, B3)
+    end;
+mime_decode_list_to_string_after_eq([], B1, B2, eq) ->
+    binary_to_list(<<B1:6,(B2 bsr 4):2>>);
+mime_decode_list_to_string_after_eq([], B1, B2, B3) ->
+    binary_to_list(<<B1:6,B2:6,(B3 bsr 2):4>>).
+
+decode_list([C1 | Cs], A) ->
+    case b64d(C1) of
+        ws -> decode_list(Cs, A);
+        B1 -> decode_list(Cs, A, B1)
+    end;
+decode_list([], A) ->
+    A.
 
-%% Skipping pad character if not at end of string. Also liberal about
-%% excess padding and skipping of other illegal (non-base64 alphabet)
-%% characters. See section 3.3 of RFC4648
-strip_illegal([], A, _Cnt) ->
+decode_list([C2 | Cs], A, B1) ->
+    case b64d(C2) of
+        ws -> decode_list(Cs, A, B1);
+        B2 -> decode_list(Cs, A, B1, B2)
+    end.
+
+decode_list([C3 | Cs], A, B1, B2) ->
+    case b64d(C3) of
+        ws -> decode_list(Cs, A, B1, B2);
+        B3 -> decode_list(Cs, A, B1, B2, B3)
+    end.
+
+decode_list([C4 | Cs], A, B1, B2, B3) ->
+    case b64d(C4) of
+        ws                -> decode_list(Cs, A, B1, B2, B3);
+        eq when B3 =:= eq -> only_ws(Cs, <<A/bits,B1:6,(B2 bsr 4):2>>);
+        eq                -> only_ws(Cs, <<A/bits,B1:6,B2:6,(B3 bsr 2):4>>);
+        B4                -> decode_list(Cs, <<A/bits,B1:6,B2:6,B3:6,B4:6>>)
+    end.
+
+decode_binary(<<C1:8, Cs/bits>>, A) ->
+    case b64d(C1) of
+        ws -> decode_binary(Cs, A);
+        B1 -> decode_binary(Cs, A, B1)
+    end;
+decode_binary(<<>>, A) ->
+    A.
+
+decode_binary(<<C2:8, Cs/bits>>, A, B1) ->
+    case b64d(C2) of
+        ws -> decode_binary(Cs, A, B1);
+        B2 -> decode_binary(Cs, A, B1, B2)
+    end.
+
+decode_binary(<<C3:8, Cs/bits>>, A, B1, B2) ->
+    case b64d(C3) of
+        ws -> decode_binary(Cs, A, B1, B2);
+        B3 -> decode_binary(Cs, A, B1, B2, B3)
+    end.
+
+decode_binary(<<C4:8, Cs/bits>>, A, B1, B2, B3) ->
+    case b64d(C4) of
+        ws                -> decode_binary(Cs, A, B1, B2, B3);
+        eq when B3 =:= eq -> only_ws_binary(Cs, <<A/bits,B1:6,(B2 bsr 4):2>>);
+        eq                -> only_ws_binary(Cs, <<A/bits,B1:6,B2:6,(B3 bsr 2):4>>);
+        B4                -> decode_binary(Cs, <<A/bits,B1:6,B2:6,B3:6,B4:6>>)
+    end.
+
+only_ws_binary(<<>>, A) ->
     A;
-strip_illegal([0|Cs], A, Cnt) ->
-    strip_illegal(Cs, A, Cnt);
-strip_illegal([C|Cs], A, Cnt) ->
-    case element(C, ?DECODE_MAP) of
-	bad ->
-	    strip_illegal(Cs, A, Cnt);
-	ws ->
-	    strip_illegal(Cs, A, Cnt);
-	eq ->
-	    case {tail_contains_more(Cs, false), Cnt rem 4} of
-		{{[], _}, 0} ->
-		    A;            %% Ignore extra =
-		{{[], true}, 2} ->
-		    [$=|[$=|A]];  %% 'XX=='
-		{{[], _}, 3} ->
-		    [$=|A];       %% 'XXX='
-		{{[H|T], _}, _} ->
-		    %% more data, skip equals
-		    strip_illegal(T, [H|A], Cnt+1)
-	    end;
-	_ ->
-	    strip_illegal(Cs, [C|A], Cnt+1)
+only_ws_binary(<<C:8, Cs/bits>>, A) ->
+    case b64d(C) of
+        ws -> only_ws_binary(Cs, A)
     end.
 
-%% Search the tail for more valid data and remember if we saw
-%% another equals along the way.
-tail_contains_more([], Eq) ->
-    {[], Eq};
-tail_contains_more(<<>>, Eq) ->
-    {<<>>, Eq};
-tail_contains_more([C|T]=More, Eq) ->
-    case element(C, ?DECODE_MAP) of
-	bad ->
-	    tail_contains_more(T, Eq);
-	ws ->
-	    tail_contains_more(T, Eq);
-	eq ->
-	    tail_contains_more(T, true);
-	_ ->
-	    {More, Eq}
+decode_list_to_string([C1 | Cs]) ->
+    case b64d(C1) of
+        ws -> decode_list_to_string(Cs);
+        B1 -> decode_list_to_string(Cs, B1)
     end;
-tail_contains_more(<<C:8,T/bits>> =More, Eq) ->
-    case element(C, ?DECODE_MAP) of
-	bad ->
-	    tail_contains_more(T, Eq);
-	ws ->
-	    tail_contains_more(T, Eq);
-	eq ->
-	    tail_contains_more(T, true);
-	_ ->
-	    {More, Eq}
+decode_list_to_string([]) ->
+    [].
+
+decode_list_to_string([C2 | Cs], B1) ->
+    case b64d(C2) of
+        ws -> decode_list_to_string(Cs, B1);
+        B2 -> decode_list_to_string(Cs, B1, B2)
     end.
-    
+
+decode_list_to_string([C3 | Cs], B1, B2) ->
+    case b64d(C3) of
+        ws -> decode_list_to_string(Cs, B1, B2);
+        B3 -> decode_list_to_string(Cs, B1, B2, B3)
+    end.
+
+decode_list_to_string([C4 | Cs], B1, B2, B3) ->
+    case b64d(C4) of
+        ws ->
+            decode_list_to_string(Cs, B1, B2, B3);
+        eq when B3 =:= eq ->
+            only_ws(Cs, binary_to_list(<<B1:6,(B2 bsr 4):2>>));
+        eq ->
+            only_ws(Cs, binary_to_list(<<B1:6,B2:6,(B3 bsr 2):4>>));
+        B4 ->
+            Bits4x6 = (B1 bsl 18) bor (B2 bsl 12) bor (B3 bsl 6) bor B4,
+            Octet1 = Bits4x6 bsr 16,
+            Octet2 = (Bits4x6 bsr 8) band 16#ff,
+            Octet3 = Bits4x6 band 16#ff,
+            [Octet1, Octet2, Octet3 | decode_list_to_string(Cs)]
+    end.
+
+only_ws([], A) ->
+    A;
+only_ws([C | Cs], A) ->
+    case b64d(C) of
+        ws -> only_ws(Cs, A)
+    end.
+
+%%%========================================================================
+%%% Internal functions
+%%%========================================================================
+
 %% accessors 
+-compile({inline, [{b64d, 1}]}).
+%% One-based decode map.
+b64d(X) ->
+    element(X,
+            {bad,bad,bad,bad,bad,bad,bad,bad,ws,ws,bad,bad,ws,bad,bad, %1-15
+             bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad, %16-31
+             ws,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,62,bad,bad,bad,63, %32-47
+             52,53,54,55,56,57,58,59,60,61,bad,bad,bad,eq,bad,bad, %48-63
+             bad,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,
+             15,16,17,18,19,20,21,22,23,24,25,bad,bad,bad,bad,bad,
+             bad,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,
+             41,42,43,44,45,46,47,48,49,50,51,bad,bad,bad,bad,bad,
+             bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
+             bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
+             bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
+             bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
+             bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
+             bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
+             bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,
+             bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad,bad}).
+
+-compile({inline, [{b64e, 1}]}).
 b64e(X) ->
     element(X+1,
 	    {$A, $B, $C, $D, $E, $F, $G, $H, $I, $J, $K, $L, $M, $N,
@@ -368,9 +463,3 @@ b64e(X) ->
 	     $a, $b, $c, $d, $e, $f, $g, $h, $i, $j, $k, $l, $m, $n,
 	     $o, $p, $q, $r, $s, $t, $u, $v, $w, $x, $y, $z,
 	     $0, $1, $2, $3, $4, $5, $6, $7, $8, $9, $+, $/}).
-
-
-b64d(X) ->
-    b64d_ok(element(X, ?DECODE_MAP)).
-
-b64d_ok(I) when is_integer(I) -> I.
diff --git a/lib/stdlib/src/c.erl b/lib/stdlib/src/c.erl
index c04a201ce1..9a447af5b7 100644
--- a/lib/stdlib/src/c.erl
+++ b/lib/stdlib/src/c.erl
@@ -668,19 +668,23 @@ lm() ->
     [l(M) || M <- mm()].
 
 %% erlangrc(Home)
-%%  Try to run a ".erlang" file, first in the current directory
-%%  else in home directory.
+%%  Try to run a ".erlang" file in home directory.
+
+-spec erlangrc() -> {ok, file:filename()} | {error, term()}.
 
 erlangrc() ->
     case init:get_argument(home) of
 	{ok,[[Home]]} ->
 	    erlangrc([Home]);
 	_ ->
-	    f_p_e(["."], ".erlang")
+            {error, enoent}
     end.
 
-erlangrc([Home]) ->
-    f_p_e([".",Home], ".erlang").
+-spec erlangrc(PathList) -> {ok, file:filename()} | {error, term()}
+                                when PathList :: [Dir :: file:name()].
+
+erlangrc([Home|_]=Paths) when is_list(Home) ->
+    f_p_e(Paths, ".erlang").
 
 error(Fmt, Args) ->
     error_logger:error_msg(Fmt, Args).
@@ -692,11 +696,11 @@ f_p_e(P, F) ->
 	{error, E={Line, _Mod, _Term}} ->
 	    error("file:path_eval(~tp,~tp): error on line ~p: ~ts~n",
 		  [P, F, Line, file:format_error(E)]),
-	    ok;
+	    {error, E};
 	{error, E} ->
 	    error("file:path_eval(~tp,~tp): ~ts~n",
 		  [P, F, file:format_error(E)]),
-	    ok;
+	    {error, E};
 	Other ->
 	    Other
     end.
diff --git a/lib/stdlib/src/epp.erl b/lib/stdlib/src/epp.erl
index 31d0d499e3..00e6a10d8a 100644
--- a/lib/stdlib/src/epp.erl
+++ b/lib/stdlib/src/epp.erl
@@ -479,7 +479,7 @@ com_enc(_B, _Fun, _N, L, Ps) ->
     com_enc_end([L | Ps]).
 
 com_enc_end(Ps0) ->
-    Ps = lists:reverse([lists:reverse(string:to_lower(P)) || P <- Ps0]),
+    Ps = lists:reverse([lists:reverse(lowercase(P)) || P <- Ps0]),
     com_encoding(Ps).
 
 com_encoding(["latin","1"|_]) ->
@@ -489,6 +489,9 @@ com_encoding(["utf","8"|_]) ->
 com_encoding(_) ->
     throw(no). % Don't try any further
 
+lowercase(S) ->
+    unicode:characters_to_list(string:lowercase(S)).
+
 normalize_typed_record_fields([]) ->
     {typed, []};
 normalize_typed_record_fields(Fields) ->
diff --git a/lib/stdlib/src/erl_compile.erl b/lib/stdlib/src/erl_compile.erl
index 18d7548fdc..f781312ca2 100644
--- a/lib/stdlib/src/erl_compile.erl
+++ b/lib/stdlib/src/erl_compile.erl
@@ -188,6 +188,8 @@ parse_dep_option("", T) ->
     {[makedep,{makedep_output,standard_io}],T};
 parse_dep_option("D", T) ->
     {[makedep],T};
+parse_dep_option("MD", T) ->
+    {[makedep_side_effect],T};
 parse_dep_option("F"++Opt, T0) ->
     {File,T} = get_option("MF", Opt, T0),
     {[makedep,{makedep_output,File}],T};
@@ -221,6 +223,7 @@ usage() ->
 	  "the dependencies"},
 	 {"-MP","add a phony target for each dependency"},
 	 {"-MD","same as -M -MT file (with default 'file')"},
+	 {"-MMD","generate dependencies as a side-effect"},
 	 {"-o name","name output directory or file"},
 	 {"-pa path","add path to the front of Erlang's code path"},
 	 {"-pz path","add path to the end of Erlang's code path"},
diff --git a/lib/stdlib/src/erl_lint.erl b/lib/stdlib/src/erl_lint.erl
index 9cd4727dc3..1930c462e8 100644
--- a/lib/stdlib/src/erl_lint.erl
+++ b/lib/stdlib/src/erl_lint.erl
@@ -144,6 +144,7 @@ value_option(Flag, Default, On, OnVal, Off, OffVal, Opts) ->
                    :: dict:dict(ta(), #typeinfo{}),
                exp_types=gb_sets:empty()        %Exported types
                    :: gb_sets:set(ta()),
+               in_try_head=false :: boolean(),  %In a try head.
                catch_scope = none               %Inside/outside try or catch
                    :: catch_scope()
               }).
@@ -312,6 +313,10 @@ format_error({unused_var, V}) ->
     io_lib:format("variable ~w is unused", [V]);
 format_error({variable_in_record_def,V}) ->
     io_lib:format("variable ~w in record definition", [V]);
+format_error({stacktrace_guard,V}) ->
+    io_lib:format("stacktrace variable ~w must not be used in a guard", [V]);
+format_error({stacktrace_bound,V}) ->
+    io_lib:format("stacktrace variable ~w must not be previously bound", [V]);
 %% --- binaries ---
 format_error({undefined_bittype,Type}) ->
     io_lib:format("bit type ~tw undefined", [Type]);
@@ -3218,11 +3223,11 @@ is_module_dialyzer_option(Option) ->
 
 try_clauses(Scs, Ccs, In, Vt, St0) ->
     {Csvt0,St1} = icrt_clauses(Scs, Vt, St0),
-    St2 = St1#lint{catch_scope=try_catch},
+    St2 = St1#lint{catch_scope=try_catch,in_try_head=true},
     {Csvt1,St3} = icrt_clauses(Ccs, Vt, St2),
     Csvt = Csvt0 ++ Csvt1,
     UpdVt = icrt_export(Csvt, Vt, In, St3),
-    {UpdVt,St3}.
+    {UpdVt,St3#lint{in_try_head=false}}.
 
 %% icrt_clauses(Clauses, In, ImportVarTable, State) ->
 %%      {UpdVt,State}.
@@ -3239,12 +3244,29 @@ icrt_clauses(Cs, Vt, St) ->
     mapfoldl(fun (C, St0) -> icrt_clause(C, Vt, St0) end, St, Cs).
 
 icrt_clause({clause,_Line,H,G,B}, Vt0, #lint{catch_scope=Scope}=St0) ->
-    {Hvt,Binvt,St1} = head(H, Vt0, St0),
-    Vt1 = vtupdate(Hvt, Binvt),
-    {Gvt,St2} = guard(G, vtupdate(Vt1, Vt0), St1),
-    Vt2 = vtupdate(Gvt, Vt1),
-    {Bvt,St3} = exprs(B, vtupdate(Vt2, Vt0), St2),
-    {vtupdate(Bvt, Vt2),St3#lint{catch_scope=Scope}}.
+    Vt1 = taint_stack_var(Vt0, H, St0),
+    {Hvt,Binvt,St1} = head(H, Vt1, St0),
+    Vt2 = vtupdate(Hvt, Binvt),
+    Vt3 = taint_stack_var(Vt2, H, St0),
+    {Gvt,St2} = guard(G, vtupdate(Vt3, Vt0), St1#lint{in_try_head=false}),
+    Vt4 = vtupdate(Gvt, Vt2),
+    {Bvt,St3} = exprs(B, vtupdate(Vt4, Vt0), St2),
+    {vtupdate(Bvt, Vt4),St3#lint{catch_scope=Scope}}.
+
+taint_stack_var(Vt, Pat, #lint{in_try_head=true}) ->
+    [{tuple,_,[_,_,{var,_,Stk}]}] = Pat,
+    case Stk of
+        '_' ->
+            Vt;
+        _ ->
+            lists:map(fun({V,{bound,Used,Lines}}) when V =:= Stk ->
+                              {V,{stacktrace,Used,Lines}};
+                         (B) ->
+                              B
+                      end, Vt)
+    end;
+taint_stack_var(Vt, _Pat, #lint{in_try_head=false}) ->
+    Vt.
 
 icrt_export(Vts, Vt, {Tag,Attrs}, St) ->
     {_File,Loc} = loc(Attrs, St),
@@ -3484,6 +3506,9 @@ pat_var(V, Line, Vt, Bvt, St) ->
                     {[{V,{bound,used,Ls}}],[],
                      %% As this is matching, exported vars are risky.
                      add_warning(Line, {exported_var,V,From}, St)};
+                {ok,{stacktrace,_Usage,Ls}} ->
+                    {[{V,{bound,used,Ls}}],[],
+                     add_error(Line, {stacktrace_bound,V}, St)};
                 error when St#lint.recdef_top ->
                     {[],[{V,{bound,unused,[Line]}}],
                      add_error(Line, {variable_in_record_def,V}, St)};
@@ -3541,6 +3566,9 @@ expr_var(V, Line, Vt, St) ->
                 false ->
                     {[{V,{{export,From},used,Ls}}],St}
             end;
+        {ok,{stacktrace,_Usage,Ls}} ->
+            {[{V,{bound,used,Ls}}],
+             add_error(Line, {stacktrace_guard,V}, St)};
         error ->
             {[{V,{bound,used,[Line]}}],
              add_error(Line, {unbound_var,V}, St)}
@@ -3910,10 +3938,9 @@ check_format_string(Fmt) ->
     extract_sequences(Fmt, []).
 
 extract_sequences(Fmt, Need0) ->
-    case string:chr(Fmt, $~) of
-        0 -> {ok,lists:reverse(Need0)};         %That's it
-        Pos ->
-            Fmt1 = string:substr(Fmt, Pos+1),   %Skip ~
+    case string:find(Fmt, [$~]) of
+        nomatch -> {ok,lists:reverse(Need0)};         %That's it
+        [$~|Fmt1] ->
             case extract_sequence(1, Fmt1, Need0) of
                 {ok,Need1,Rest} -> extract_sequences(Rest, Need1);
                 Error -> Error
diff --git a/lib/stdlib/src/erl_parse.yrl b/lib/stdlib/src/erl_parse.yrl
index 6e72d64acc..14ca24362e 100644
--- a/lib/stdlib/src/erl_parse.yrl
+++ b/lib/stdlib/src/erl_parse.yrl
@@ -29,6 +29,10 @@ clause_args clause_guard clause_body
 expr expr_100 expr_150 expr_160 expr_200 expr_300 expr_400 expr_500
 expr_600 expr_700 expr_800
 expr_max
+pat_expr pat_expr_200 pat_expr_300 pat_expr_400 pat_expr_500
+pat_expr_600 pat_expr_700 pat_expr_800
+pat_expr_max map_pat_expr record_pat_expr
+pat_argument_list pat_exprs
 list tail
 list_comprehension lc_expr lc_exprs
 binary_comprehension
@@ -37,7 +41,7 @@ record_expr record_tuple record_field record_fields
 map_expr map_tuple map_field map_field_assoc map_field_exact map_fields map_key
 if_expr if_clause if_clauses case_expr cr_clause cr_clauses receive_expr
 fun_expr fun_clause fun_clauses atom_or_var integer_or_var
-try_expr try_catch try_clause try_clauses
+try_expr try_catch try_clause try_clauses try_opt_stacktrace
 function_call argument_list
 exprs guard
 atomic strings
@@ -66,7 +70,7 @@ char integer float atom string var
 'spec' 'callback' % helper
 dot.
 
-Expect 2.
+Expect 0.
 
 Rootsymbol form.
 
@@ -210,7 +214,7 @@ function_clause -> atom clause_args clause_guard clause_body :
 	{clause,?anno('$1'),element(3, '$1'),'$2','$3','$4'}.
 
 
-clause_args -> argument_list : element(1, '$1').
+clause_args -> pat_argument_list : element(1, '$1').
 
 clause_guard -> 'when' guard : '$2'.
 clause_guard -> '$empty' : [].
@@ -275,6 +279,53 @@ expr_max -> receive_expr : '$1'.
 expr_max -> fun_expr : '$1'.
 expr_max -> try_expr : '$1'.
 
+pat_expr -> pat_expr_200 '=' pat_expr : {match,?anno('$2'),'$1','$3'}.
+pat_expr -> pat_expr_200 : '$1'.
+
+pat_expr_200 -> pat_expr_300 comp_op pat_expr_300 :
+	?mkop2('$1', '$2', '$3').
+pat_expr_200 -> pat_expr_300 : '$1'.
+
+pat_expr_300 -> pat_expr_400 list_op pat_expr_300 :
+	?mkop2('$1', '$2', '$3').
+pat_expr_300 -> pat_expr_400 : '$1'.
+
+pat_expr_400 -> pat_expr_400 add_op pat_expr_500 :
+	?mkop2('$1', '$2', '$3').
+pat_expr_400 -> pat_expr_500 : '$1'.
+
+pat_expr_500 -> pat_expr_500 mult_op pat_expr_600 :
+	?mkop2('$1', '$2', '$3').
+pat_expr_500 -> pat_expr_600 : '$1'.
+
+pat_expr_600 -> prefix_op pat_expr_700 :
+	?mkop1('$1', '$2').
+pat_expr_600 -> map_pat_expr : '$1'.
+pat_expr_600 -> pat_expr_700 : '$1'.
+
+pat_expr_700 -> record_pat_expr : '$1'.
+pat_expr_700 -> pat_expr_800 : '$1'.
+
+pat_expr_800 -> pat_expr_max : '$1'.
+
+pat_expr_max -> var : '$1'.
+pat_expr_max -> atomic : '$1'.
+pat_expr_max -> list : '$1'.
+pat_expr_max -> binary : '$1'.
+pat_expr_max -> tuple : '$1'.
+pat_expr_max -> '(' pat_expr ')' : '$2'.
+
+map_pat_expr -> '#' map_tuple :
+	{map, ?anno('$1'),'$2'}.
+map_pat_expr -> pat_expr_max '#' map_tuple :
+	{map, ?anno('$2'),'$1','$3'}.
+map_pat_expr -> map_pat_expr '#' map_tuple :
+	{map, ?anno('$2'),'$1','$3'}.
+
+record_pat_expr -> '#' atom '.' atom :
+	{record_index,?anno('$1'),element(3, '$2'),'$4'}.
+record_pat_expr -> '#' atom record_tuple :
+	{record,?anno('$1'),element(3, '$2'),'$3'}.
 
 list -> '[' ']' : {nil,?anno('$1')}.
 list -> '[' expr tail : {cons,?anno('$1'),'$2','$3'}.
@@ -397,6 +448,10 @@ case_expr -> 'case' expr 'of' cr_clauses 'end' :
 cr_clauses -> cr_clause : ['$1'].
 cr_clauses -> cr_clause ';' cr_clauses : ['$1' | '$3'].
 
+%% FIXME: merl in syntax_tools depends on patterns in a 'case' being
+%% full expressions. Therefore, we can't use pat_expr here. There
+%% should be a better way.
+
 cr_clause -> expr clause_guard clause_body :
 	{clause,?anno('$1'),['$1'],'$2','$3'}.
 
@@ -424,11 +479,11 @@ integer_or_var -> var : '$1'.
 fun_clauses -> fun_clause : ['$1'].
 fun_clauses -> fun_clause ';' fun_clauses : ['$1' | '$3'].
 
-fun_clause -> argument_list clause_guard clause_body :
+fun_clause -> pat_argument_list clause_guard clause_body :
 	{Args,Anno} = '$1',
 	{clause,Anno,'fun',Args,'$2','$3'}.
 
-fun_clause -> var argument_list clause_guard clause_body :
+fun_clause -> var pat_argument_list clause_guard clause_body :
 	{clause,element(2, '$1'),element(3, '$1'),element(1, '$2'),'$3','$4'}.
 
 try_expr -> 'try' exprs 'of' cr_clauses try_catch :
@@ -446,24 +501,31 @@ try_catch -> 'after' exprs 'end' :
 try_clauses -> try_clause : ['$1'].
 try_clauses -> try_clause ';' try_clauses : ['$1' | '$3'].
 
-try_clause -> expr clause_guard clause_body :
+try_clause -> pat_expr clause_guard clause_body :
 	A = ?anno('$1'),
 	{clause,A,[{tuple,A,[{atom,A,throw},'$1',{var,A,'_'}]}],'$2','$3'}.
-try_clause -> atom ':' expr clause_guard clause_body :
+try_clause -> atom ':' pat_expr try_opt_stacktrace clause_guard clause_body :
 	A = ?anno('$1'),
-	{clause,A,[{tuple,A,['$1','$3',{var,A,'_'}]}],'$4','$5'}.
-try_clause -> var ':' expr clause_guard clause_body :
+	{clause,A,[{tuple,A,['$1','$3',{var,A,'$4'}]}],'$5','$6'}.
+try_clause -> var ':' pat_expr try_opt_stacktrace clause_guard clause_body :
 	A = ?anno('$1'),
-	{clause,A,[{tuple,A,['$1','$3',{var,A,'_'}]}],'$4','$5'}.
+	{clause,A,[{tuple,A,['$1','$3',{var,A,'$4'}]}],'$5','$6'}.
 
+try_opt_stacktrace -> ':' var : element(3, '$2').
+try_opt_stacktrace -> '$empty' : '_'.
 
 argument_list -> '(' ')' : {[],?anno('$1')}.
 argument_list -> '(' exprs ')' : {'$2',?anno('$1')}.
 
+pat_argument_list -> '(' ')' : {[],?anno('$1')}.
+pat_argument_list -> '(' pat_exprs ')' : {'$2',?anno('$1')}.
 
 exprs -> expr : ['$1'].
 exprs -> expr ',' exprs : ['$1' | '$3'].
 
+pat_exprs -> pat_expr : ['$1'].
+pat_exprs -> pat_expr ',' pat_exprs : ['$1' | '$3'].
+
 guard -> exprs : ['$1'].
 guard -> exprs ';' guard : ['$1'|'$3'].
 
diff --git a/lib/stdlib/src/erl_pp.erl b/lib/stdlib/src/erl_pp.erl
index ee5e7a11bf..367dbefb82 100644
--- a/lib/stdlib/src/erl_pp.erl
+++ b/lib/stdlib/src/erl_pp.erl
@@ -237,13 +237,20 @@ lform({attribute,Line,Name,Arg}, Opts) ->
 lform({function,Line,Name,Arity,Clauses}, Opts) ->
     lfunction({function,Line,Name,Arity,Clauses}, Opts);
 %% These are specials to make it easier for the compiler.
-lform({error,E}, _Opts) ->
-    leaf(format("~p\n", [{error,E}]));
-lform({warning,W}, _Opts) ->
-    leaf(format("~p\n", [{warning,W}]));
+lform({error,_}=E, Opts) ->
+    message(E, Opts);
+lform({warning,_}=W, Opts) ->
+    message(W, Opts);
 lform({eof,_Line}, _Opts) ->
     $\n.
 
+message(M, #options{encoding = Encoding}) ->
+    F = case Encoding of
+            latin1 -> "~p\n";
+            unicode -> "~tp\n"
+        end,
+    leaf(format(F, [M])).
+
 lattribute({attribute,_Line,type,Type}, Opts) ->
     [typeattr(type, Type, Opts),leaf(".\n")];
 lattribute({attribute,_Line,opaque,Type}, Opts) ->
@@ -598,8 +605,6 @@ lexpr({'fun',_,{clauses,Cs},Extra}, _Prec, Opts) ->
 lexpr({named_fun,_,Name,Cs,Extra}, _Prec, Opts) ->
     {force_nl,fun_info(Extra),
      {list,[{first,['fun', " "],fun_clauses(Cs, Opts, {named, Name})},'end']}};
-lexpr({'query',_,Lc}, _Prec, Opts) ->
-    {list,[{step,leaf("query"),lexpr(Lc, 0, Opts)},'end']};
 lexpr({call,_,{remote,_,{atom,_,M},{atom,_,F}=N}=Name,Args}, Prec, Opts) ->
     case erl_internal:bif(M, F, length(Args)) of
         true ->
@@ -904,7 +909,7 @@ maybe_paren(_P, _Prec, Expr) ->
     Expr.
 
 leaf(S) ->
-    {leaf,chars_size(S),S}.
+    {leaf,string:length(S),S}.
 
 %%% Do the formatting. Currently nothing fancy. Could probably have
 %%% done it in one single pass.
@@ -964,7 +969,7 @@ f({seq,Before,After,Sep,LItems}, I0, ST, WT, PP) ->
     Sizes = BSizeL ++ SizeL,
     NSepChars = if
                     is_list(Sep), Sep =/= [] ->
-                        erlang:max(0, length(CharsL)-1);
+                        erlang:max(0, length(CharsL)-1); % not string:length
                     true ->
                         0
                 end,
@@ -1120,7 +1125,7 @@ incr(I, Incr) ->
     I+Incr.
 
 indentation(E, I) when I < 0 ->
-    chars_size(E);
+    string:length(E);
 indentation(E, I0) ->
     I = io_lib_format:indentation(E, I0),
     case has_nl(E) of
@@ -1157,19 +1162,19 @@ write_a_string(S, I, PP) ->
 write_a_string([], _N, _Len, _PP) ->
     [];
 write_a_string(S, N, Len, PP) ->
-    SS = string:sub_string(S, 1, N),
+    SS = string:slice(S, 0, N),
     Sl = write_string(SS, PP),
-    case (chars_size(Sl) > Len) and (N > ?MIN_SUBSTRING) of
+    case (string:length(Sl) > Len) and (N > ?MIN_SUBSTRING) of
         true ->
             write_a_string(S, N-1, Len, PP);
         false ->
             [flat_leaf(Sl) |
-             write_a_string(lists:nthtail(length(SS), S), Len, Len, PP)]
+             write_a_string(string:slice(S, string:length(SS)), Len, Len, PP)]
     end.
 
 flat_leaf(S) ->
     L = lists:flatten(S),
-    {leaf,length(L),L}.
+    {leaf,string:length(L),L}.
 
 write_value(V, PP) ->
     (PP#pp.value_fun)(V).
@@ -1190,15 +1195,6 @@ write_char(C, PP) ->
 a0() ->
     erl_anno:new(0).
 
-chars_size([C | Es]) when is_integer(C) ->
-    1 + chars_size(Es);
-chars_size([E | Es]) ->
-    chars_size(E) + chars_size(Es);
-chars_size([]) ->
-    0;
-chars_size(B) when is_binary(B) ->
-    byte_size(B).
-
 -define(N_SPACES, 30).
 
 spacetab() ->
diff --git a/lib/stdlib/src/erl_scan.erl b/lib/stdlib/src/erl_scan.erl
index 47223b129c..4774c4bf19 100644
--- a/lib/stdlib/src/erl_scan.erl
+++ b/lib/stdlib/src/erl_scan.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2015. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2017. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -752,7 +752,7 @@ scan_string(Cs, St, Line, Col, Toks, {Wcs,Str,Line0,Col0}) ->
         {char_error,Ncs,Error,Nline,Ncol,EndCol} ->
             scan_error(Error, Nline, Ncol, Nline, EndCol, Ncs);
         {error,Nline,Ncol,Nwcs,Ncs} ->
-            Estr = string:substr(Nwcs, 1, 16), % Expanded escape chars.
+            Estr = string:slice(Nwcs, 0, 16), % Expanded escape chars.
             scan_error({string,$\",Estr}, Line0, Col0, Nline, Ncol, Ncs); %"
         {Ncs,Nline,Ncol,Nstr,Nwcs} ->
             Anno = anno(Line0, Col0, St, Nstr),
@@ -767,7 +767,7 @@ scan_qatom(Cs, St, Line, Col, Toks, {Wcs,Str,Line0,Col0}) ->
         {char_error,Ncs,Error,Nline,Ncol,EndCol} ->
             scan_error(Error, Nline, Ncol, Nline, EndCol, Ncs);
         {error,Nline,Ncol,Nwcs,Ncs} ->
-            Estr = string:substr(Nwcs, 1, 16), % Expanded escape chars.
+            Estr = string:slice(Nwcs, 0, 16), % Expanded escape chars.
             scan_error({string,$\',Estr}, Line0, Col0, Nline, Ncol, Ncs); %'
         {Ncs,Nline,Ncol,Nstr,Nwcs} ->
             case catch list_to_atom(Nwcs) of
diff --git a/lib/stdlib/src/escript.erl b/lib/stdlib/src/escript.erl
index 2b9d8ff65b..132f8efbbe 100644
--- a/lib/stdlib/src/escript.erl
+++ b/lib/stdlib/src/escript.erl
@@ -224,8 +224,8 @@ return_sections(S, Bin) ->
 normalize_section(Name, undefined) ->
     {Name, undefined};
 normalize_section(shebang, "#!" ++ Chars) ->
-    Chopped = string:strip(Chars, right, $\n),
-    Stripped = string:strip(Chopped, both),
+    Chopped = string:trim(Chars, trailing, "$\n"),
+    Stripped = string:trim(Chopped, both),
     if
 	Stripped =:= ?SHEBANG ->
 	    {shebang, default};
@@ -233,8 +233,8 @@ normalize_section(shebang, "#!" ++ Chars) ->
 	    {shebang, Stripped}
     end;
 normalize_section(comment, Chars) ->
-    Chopped = string:strip(Chars, right, $\n),
-    Stripped = string:strip(string:strip(Chopped, left, $%), both),
+    Chopped = string:trim(Chars, trailing, "$\n"),
+    Stripped = string:trim(string:trim(Chopped, leading, "$%"), both),
     if
 	Stripped =:= ?COMMENT ->
 	    {comment, default};
@@ -242,8 +242,8 @@ normalize_section(comment, Chars) ->
 	    {comment, Stripped}
     end;
 normalize_section(emu_args, "%%!" ++ Chars) ->
-    Chopped = string:strip(Chars, right, $\n),
-    Stripped = string:strip(Chopped, both),
+    Chopped = string:trim(Chars, trailing, "$\n"),
+    Stripped = string:trim(Chopped, both),
     {emu_args, Stripped};
 normalize_section(Name, Chars) ->
     {Name, Chars}.
diff --git a/lib/stdlib/src/ets.erl b/lib/stdlib/src/ets.erl
index 1db004c91e..b6548626f3 100644
--- a/lib/stdlib/src/ets.erl
+++ b/lib/stdlib/src/ets.erl
@@ -1719,7 +1719,7 @@ get_line(P, Default) ->
 line_string(Binary) when is_binary(Binary) -> unicode:characters_to_list(Binary);
 line_string(Other) -> Other.
 
-nonl(S) -> string:strip(S, right, $\n).
+nonl(S) -> string:trim(S, trailing, "$\n").
 
 print_number(Tab, Key, Num) ->
     Os = ets:lookup(Tab, Key),
@@ -1748,7 +1748,7 @@ do_display_item(_Height, Width, I, Opos)  ->
     L = to_string(I),
     L2 = if
 	     length(L) > Width - 8 ->
-                 string:substr(L, 1, Width-13) ++ "  ...";
+                 string:slice(L, 0, Width-13) ++ "  ...";
 	     true ->
 		 L
 	 end,
diff --git a/lib/stdlib/src/filelib.erl b/lib/stdlib/src/filelib.erl
index d7c313f214..0f90b3fc33 100644
--- a/lib/stdlib/src/filelib.erl
+++ b/lib/stdlib/src/filelib.erl
@@ -365,11 +365,18 @@ do_list_dir(Dir, Mod) ->     eval_list_dir(Dir, Mod).
 	    
 %%% Compiling a wildcard.
 
+
+%% Define characters used for escaping a \.
+-define(ESCAPE_PREFIX, $@).
+-define(ESCAPE_CHARACTER, [?ESCAPE_PREFIX,$e]).
+-define(ESCAPED_ESCAPE_PREFIX, [?ESCAPE_PREFIX,?ESCAPE_PREFIX]).
+
 %% Only for debugging.
 compile_wildcard(Pattern) when is_list(Pattern) ->
     {compiled_wildcard,?HANDLE_ERROR(compile_wildcard(Pattern, "."))}.
 
-compile_wildcard(Pattern, Cwd0) ->
+compile_wildcard(Pattern0, Cwd0) ->
+    Pattern = convert_escapes(Pattern0),
     [Root|Rest] = filename:split(Pattern),
     case filename:pathtype(Root) of
 	relative ->
@@ -409,7 +416,8 @@ compile_join({cwd,Cwd}, File0) ->
 compile_join({root,PrefixLen,Root}, File) ->
     {root,PrefixLen,filename:join(Root, File)}.
 
-compile_part(Part) ->
+compile_part(Part0) ->
+    Part = wrap_escapes(Part0),
     compile_part(Part, false, []).
 
 compile_part_to_sep(Part) ->
@@ -445,6 +453,8 @@ compile_part([${|Rest], Upto, Result) ->
 	error ->
 	    compile_part(Rest, Upto, [${|Result])
     end;
+compile_part([{escaped,X}|Rest], Upto, Result) ->
+    compile_part(Rest, Upto, [X|Result]);
 compile_part([X|Rest], Upto, Result) ->
     compile_part(Rest, Upto, [X|Result]);
 compile_part([], _Upto, Result) ->
@@ -461,6 +471,8 @@ compile_charset1([Lower, $-, Upper|Rest], Ordset) when Lower =< Upper ->
     compile_charset1(Rest, compile_range(Lower, Upper, Ordset));
 compile_charset1([$]|Rest], Ordset) ->
     {ok, {one_of, gb_sets:from_ordset(Ordset)}, Rest};
+compile_charset1([{escaped,X}|Rest], Ordset) ->
+    compile_charset1(Rest, ordsets:add_element(X, Ordset));
 compile_charset1([X|Rest], Ordset) ->
     compile_charset1(Rest, ordsets:add_element(X, Ordset));
 compile_charset1([], _Ordset) ->
@@ -486,6 +498,32 @@ compile_alt(Pattern, Result) ->
 	    error
     end.
 
+%% Convert backslashes to an illegal Unicode character to
+%% protect in from filename:split/1.
+
+convert_escapes([?ESCAPE_PREFIX|T]) ->
+    ?ESCAPED_ESCAPE_PREFIX ++ convert_escapes(T);
+convert_escapes([$\\|T]) ->
+    ?ESCAPE_CHARACTER ++ convert_escapes(T);
+convert_escapes([H|T]) ->
+    [H|convert_escapes(T)];
+convert_escapes([]) ->
+    [].
+
+%% Wrap each escape in a tuple to remove the special meaning for
+%% the character that follows.
+
+wrap_escapes(?ESCAPED_ESCAPE_PREFIX ++ T) ->
+    [?ESCAPE_PREFIX|wrap_escapes(T)];
+wrap_escapes(?ESCAPE_CHARACTER ++ [C|T]) ->
+    [{escaped,C}|wrap_escapes(T)];
+wrap_escapes(?ESCAPE_CHARACTER) ->
+    [];
+wrap_escapes([H|T]) ->
+    [H|wrap_escapes(T)];
+wrap_escapes([]) ->
+    [].
+
 badpattern(Reason) ->
     error({badpattern,Reason}).
 
diff --git a/lib/stdlib/src/filename.erl b/lib/stdlib/src/filename.erl
index ee807dfd09..a322bd002d 100644
--- a/lib/stdlib/src/filename.erl
+++ b/lib/stdlib/src/filename.erl
@@ -34,6 +34,38 @@
 %% we flatten the arguments immediately on function entry as that makes
 %% it easier to ensure that the code works.
 
+%%
+%% *** Requirements on Raw Filename Format ***
+%%
+%% These requirements are due to the 'filename' module
+%% in stdlib. This since it is documented that it
+%% should be able to operate on raw filenames as well
+%% as ordinary filenames.
+%%
+%% A raw filename *must* be a byte sequence where:
+%% 1. Codepoints 0-127 (7-bit ascii) *must* be encoded
+%%    as a byte with the corresponding value. That is,
+%%    the most significant bit in the byte encoding the
+%%    codepoint is never set.
+%% 2. Codepoints greater than 127 *must* be encoded
+%%    with the most significant bit set in *every* byte
+%%    encoding it.
+%%
+%% Latin1 and UTF-8 meet these requirements while
+%% UTF-16 and UTF-32 don't.
+%%
+%% On Windows filenames are natively stored as malformed
+%% UTF-16LE (lonely surrogates may appear). A more correct
+%% description than UTF-16 would be an array of 16-bit
+%% words... In order to meet the requirements of the
+%% raw file format we convert the malformed UTF-16LE to
+%% malformed UTF-8 which meet the requirements.
+%%
+%% Note that these requirements are today only OTP
+%% internal (erts-stdlib internal) requirements that
+%% could be changed.
+%%
+
 -export([absname/1, absname/2, absname_join/2, 
 	 basename/1, basename/2, dirname/1,
 	 extension/1, join/1, join/2, pathtype/1,
@@ -41,6 +73,7 @@
          safe_relative_path/1]).
 -export([find_src/1, find_src/2]). % deprecated
 -export([basedir/2, basedir/3]).
+-export([validate/1]).
 
 %% Undocumented and unsupported exports.
 -export([append/2]).
@@ -1053,10 +1086,10 @@ basedir_linux(Type) ->
         user_log    -> getenv("XDG_CACHE_HOME", ?basedir_linux_user_log,   true);
         site_data   ->
             Base = getenv("XDG_DATA_DIRS",?basedir_linux_site_data,false),
-            string:tokens(Base,":");
+            string:lexemes(Base, ":");
         site_config ->
             Base = getenv("XDG_CONFIG_DIRS",?basedir_linux_site_config,false),
-            string:tokens(Base,":")
+            string:lexemes(Base, ":")
     end.
 
 -define(basedir_darwin_user_data,   "Library/Application Support").
@@ -1152,3 +1185,72 @@ basedir_os_type() ->
         {win32,_}     -> windows;
         _             -> linux
     end.
+
+%%
+%% validate/1
+%%
+
+-spec validate(FileName) -> boolean() when
+      FileName :: file:name_all().
+
+validate(FileName) when is_binary(FileName) ->
+    %% Raw filename...
+    validate_bin(FileName);
+validate(FileName) when is_list(FileName);
+                        is_atom(FileName) ->
+    validate_list(FileName,
+                  file:native_name_encoding(),
+                  os:type()).
+
+validate_list(FileName, Enc, Os) ->
+    try
+        true = validate_list(FileName, Enc, Os, 0) > 0
+    catch
+        _ : _ -> false
+    end.
+
+validate_list([], _Enc, _Os, Chars) ->
+    Chars;
+validate_list(C, Enc, Os, Chars) when is_integer(C) ->
+    validate_char(C, Enc, Os),
+    Chars+1;
+validate_list(A, Enc, Os, Chars) when is_atom(A) ->
+    validate_list(atom_to_list(A), Enc, Os, Chars);
+validate_list([H|T], Enc, Os, Chars) ->
+    NewChars = validate_list(H, Enc, Os, Chars),
+    validate_list(T, Enc, Os, NewChars).
+
+%% C is always an integer...
+% validate_char(C, _, _) when not is_integer(C) ->
+%     throw(invalid);
+validate_char(C, _, _) when C < 1 ->
+    throw(invalid); %% No negative or null characters...
+validate_char(C, latin1, _) when C > 255 ->
+    throw(invalid);
+validate_char(C, utf8, _) when C >= 16#110000 ->
+    throw(invalid);
+validate_char(C, utf8, {win32, _}) when C > 16#ffff ->
+    throw(invalid); %% invalid win wchar...
+validate_char(_C, utf8, {win32, _}) ->
+    ok; %% Range below is accepted on windows...
+validate_char(C, utf8, _) when 16#D800 =< C, C =< 16#DFFF ->
+    throw(invalid); %% invalid unicode range...
+validate_char(_, _, _) ->
+    ok.
+
+validate_bin(Bin) ->
+    %% Raw filename. That is, we do not interpret
+    %% the encoding, but we still do not accept
+    %% null characters...
+    try
+        true = validate_bin(Bin, 0) > 0
+    catch
+        _ : _ -> false
+    end.
+
+validate_bin(<<>>, Bs) ->
+    Bs;
+validate_bin(<<0, _Rest/binary>>, _Bs) ->
+    throw(invalid); %% No null characters allowed...
+validate_bin(<<_B, Rest/binary>>, Bs) ->
+    validate_bin(Rest, Bs+1).
diff --git a/lib/stdlib/src/gen.erl b/lib/stdlib/src/gen.erl
index 33af0aed8f..4b1d448487 100644
--- a/lib/stdlib/src/gen.erl
+++ b/lib/stdlib/src/gen.erl
@@ -49,6 +49,7 @@
                     | {'logfile', string()}.
 -type option()     :: {'timeout', timeout()}
 		    | {'debug', [debug_flag()]}
+		    | {'hibernate_after', timeout()}
 		    | {'spawn_opt', [proc_lib:spawn_option()]}.
 -type options()    :: [option()].
 
diff --git a/lib/stdlib/src/gen_server.erl b/lib/stdlib/src/gen_server.erl
index 7daa7a9fe4..ac172325b5 100644
--- a/lib/stdlib/src/gen_server.erl
+++ b/lib/stdlib/src/gen_server.erl
@@ -116,23 +116,27 @@
 %%%=========================================================================
 
 -callback init(Args :: term()) ->
-    {ok, State :: term()} | {ok, State :: term(), timeout() | hibernate} |
+    {ok, State :: term()} | {ok, State :: term(), timeout() | hibernate | {continue, term()}} |
     {stop, Reason :: term()} | ignore.
 -callback handle_call(Request :: term(), From :: {pid(), Tag :: term()},
                       State :: term()) ->
     {reply, Reply :: term(), NewState :: term()} |
-    {reply, Reply :: term(), NewState :: term(), timeout() | hibernate} |
+    {reply, Reply :: term(), NewState :: term(), timeout() | hibernate | {continue, term()}} |
     {noreply, NewState :: term()} |
-    {noreply, NewState :: term(), timeout() | hibernate} |
+    {noreply, NewState :: term(), timeout() | hibernate | {continue, term()}} |
     {stop, Reason :: term(), Reply :: term(), NewState :: term()} |
     {stop, Reason :: term(), NewState :: term()}.
 -callback handle_cast(Request :: term(), State :: term()) ->
     {noreply, NewState :: term()} |
-    {noreply, NewState :: term(), timeout() | hibernate} |
+    {noreply, NewState :: term(), timeout() | hibernate | {continue, term()}} |
     {stop, Reason :: term(), NewState :: term()}.
 -callback handle_info(Info :: timeout | term(), State :: term()) ->
     {noreply, NewState :: term()} |
-    {noreply, NewState :: term(), timeout() | hibernate} |
+    {noreply, NewState :: term(), timeout() | hibernate | {continue, term()}} |
+    {stop, Reason :: term(), NewState :: term()}.
+-callback handle_continue(Info :: term(), State :: term()) ->
+    {noreply, NewState :: term()} |
+    {noreply, NewState :: term(), timeout() | hibernate | {continue, term()}} |
     {stop, Reason :: term(), NewState :: term()}.
 -callback terminate(Reason :: (normal | shutdown | {shutdown, term()} |
                                term()),
@@ -149,7 +153,7 @@
       Status :: term().
 
 -optional_callbacks(
-    [handle_info/2, terminate/2, code_change/3, format_status/2]).
+    [handle_info/2, handle_continue/2, terminate/2, code_change/3, format_status/2]).
 
 %%%  -----------------------------------------------------------------
 %%% Starts a generic server.
@@ -309,7 +313,7 @@ enter_loop(Mod, Options, State, ServerName, Timeout) ->
     Name = gen:get_proc_name(ServerName),
     Parent = gen:get_parent(),
     Debug = gen:debug_options(Name, Options),
-	HibernateAfterTimeout = gen:hibernate_after(Options),
+    HibernateAfterTimeout = gen:hibernate_after(Options),
     loop(Parent, Name, State, Mod, Timeout, HibernateAfterTimeout, Debug).
 
 %%%========================================================================
@@ -374,6 +378,19 @@ init_it(Mod, Args) ->
 %%% ---------------------------------------------------
 %%% The MAIN loop.
 %%% ---------------------------------------------------
+
+loop(Parent, Name, State, Mod, {continue, Continue} = Msg, HibernateAfterTimeout, Debug) ->
+    Reply = try_dispatch(Mod, handle_continue, Continue, State),
+    case Debug of
+	[] ->
+	    handle_common_reply(Reply, Parent, Name, undefined, Msg, Mod,
+				HibernateAfterTimeout, State);
+	_ ->
+	    Debug1 = sys:handle_debug(Debug, fun print_event/3, Name, Msg),
+	    handle_common_reply(Reply, Parent, Name, undefined, Msg, Mod,
+				HibernateAfterTimeout, State, Debug1)
+    end;
+
 loop(Parent, Name, State, Mod, hibernate, HibernateAfterTimeout, Debug) ->
     proc_lib:hibernate(?MODULE,wake_hib,[Parent, Name, State, Mod, HibernateAfterTimeout, Debug]);
 
diff --git a/lib/stdlib/src/gen_statem.erl b/lib/stdlib/src/gen_statem.erl
index 1110d18af6..cd6312855d 100644
--- a/lib/stdlib/src/gen_statem.erl
+++ b/lib/stdlib/src/gen_statem.erl
@@ -296,7 +296,7 @@
     (Reason :: term()).
 
 %% Format the callback module state in some sensible that is
-%% often condensed way.  For StatusOption =:= 'normal' the perferred
+%% often condensed way.  For StatusOption =:= 'normal' the preferred
 %% return term is [{data,[{"State",FormattedState}]}], and for
 %% StatusOption =:= 'terminate' it is just FormattedState.
 -callback format_status(
@@ -510,8 +510,6 @@ call(ServerRef, Request, Timeout) ->
 
 parse_timeout(Timeout) ->
     case Timeout of
-	{clean_timeout,infinity} ->
-	    {dirty_timeout,infinity};
 	{clean_timeout,_} ->
 	    Timeout;
 	{dirty_timeout,_} ->
diff --git a/lib/stdlib/src/io_lib.erl b/lib/stdlib/src/io_lib.erl
index 9d447418f8..3c8430b820 100644
--- a/lib/stdlib/src/io_lib.erl
+++ b/lib/stdlib/src/io_lib.erl
@@ -963,7 +963,18 @@ limit_tail(Other, D) ->
 %% maps:from_list() creates a map with the same internal ordering of
 %% the selected associations as in Map.
 limit_map(Map, D) ->
-    maps:from_list(erts_internal:maps_to_list(Map, D)).
+    limit_map(maps:iterator(Map), D, []).
+
+limit_map(_I, 0, Acc) ->
+    maps:from_list(Acc);
+limit_map(I, D, Acc) ->
+    case maps:next(I) of
+        {K, V, NextI} ->
+            limit_map(NextI, D-1, [{K,V} | Acc]);
+        none ->
+            maps:from_list(Acc)
+    end.
+
 %%     maps:from_list(limit_map_body(erts_internal:maps_to_list(Map, D), D)).
 
 %% limit_map_body(_, 0) -> [{'...', '...'}];
diff --git a/lib/stdlib/src/io_lib_format.erl b/lib/stdlib/src/io_lib_format.erl
index 4b2d15c8b3..e345810ca0 100644
--- a/lib/stdlib/src/io_lib_format.erl
+++ b/lib/stdlib/src/io_lib_format.erl
@@ -380,7 +380,7 @@ float_e(_Fl, {Ds,E}, P) ->
 	{Fs,false} -> [Fs|float_exp(E-1)]
     end.
 
-%% float_man([Digit], Icount, Dcount) -> {[Chars],CarryFlag}.
+%% float_man([Digit], Icount, Dcount) -> {[Char],CarryFlag}.
 %%  Generate the characters in the mantissa from the digits with Icount
 %%  characters before the '.' and Dcount decimals. Handle carry and let
 %%  caller decide what to do at top.
@@ -395,7 +395,7 @@ float_man([D|Ds], I, Dc) ->
 	{Cs,false} -> {[D|Cs],false}
     end;
 float_man([], I, Dc) ->				%Pad with 0's
-    {string:chars($0, I, [$.|string:chars($0, Dc)]),false}.
+    {lists:duplicate(I, $0) ++ [$.|lists:duplicate(Dc, $0)],false}.
 
 float_man([D|_], 0) when D >= $5 -> {[],true};
 float_man([_|_], 0) -> {[],false};
@@ -405,7 +405,7 @@ float_man([D|Ds], Dc) ->
 	{Cs,true} -> {[D+1|Cs],false}; 
 	{Cs,false} -> {[D|Cs],false}
     end;
-float_man([], Dc) -> {string:chars($0, Dc),false}.	%Pad with 0's
+float_man([], Dc) -> {lists:duplicate(Dc, $0),false}.	%Pad with 0's
 
 %% float_exp(Exponent) -> [Char].
 %%  Generate the exponent of a floating point number. Always include sign.
@@ -429,7 +429,7 @@ fwrite_f(Fl, F, Adj, P, Pad) when P >= 1 ->
 float_f(Fl, Fd, P) when Fl < 0.0 ->
     [$-|float_f(-Fl, Fd, P)];
 float_f(Fl, {Ds,E}, P) when E =< 0 ->
-    float_f(Fl, {string:chars($0, -E+1, Ds),1}, P);	%Prepend enough 0's
+    float_f(Fl, {lists:duplicate(-E+1, $0)++Ds,1}, P);	%Prepend enough 0's
 float_f(_Fl, {Ds,E}, P) ->
     case float_man(Ds, E, P) of
 	{Fs,true} -> "1" ++ Fs;			%Handle carry
@@ -751,7 +751,7 @@ adjust(Data, Pad, right) -> [Pad|Data].
 flat_trunc(List, N) when is_integer(N), N >= 0 ->
     string:slice(List, 0, N).
 
-%% A deep version of string:chars/2,3
+%% A deep version of lists:duplicate/2
 
 chars(_C, 0) ->
     [];
diff --git a/lib/stdlib/src/io_lib_pretty.erl b/lib/stdlib/src/io_lib_pretty.erl
index 505613b80e..89e1931d2d 100644
--- a/lib/stdlib/src/io_lib_pretty.erl
+++ b/lib/stdlib/src/io_lib_pretty.erl
@@ -478,9 +478,19 @@ print_length(Term, _D, _RF, _Enc, _Str) ->
 print_length_map(_Map, 1, _RF, _Enc, _Str) ->
     {"#{...}", 6};
 print_length_map(Map, D, RF, Enc, Str) when is_map(Map) ->
-    Pairs = print_length_map_pairs(erts_internal:maps_to_list(Map, D), D, RF, Enc, Str),
+    Pairs = print_length_map_pairs(limit_map(maps:iterator(Map), D, []), D, RF, Enc, Str),
     {{map, Pairs}, list_length(Pairs, 3)}.
 
+limit_map(_I, 0, Acc) ->
+    Acc;
+limit_map(I, D, Acc) ->
+    case maps:next(I) of
+        {K, V, NextI} ->
+            limit_map(NextI, D-1, [{K,V} | Acc]);
+        none ->
+            Acc
+    end.
+
 print_length_map_pairs([], _D, _RF, _Enc, _Str) ->
     [];
 print_length_map_pairs(_Pairs, 1, _RF, _Enc, _Str) ->
diff --git a/lib/stdlib/src/lib.erl b/lib/stdlib/src/lib.erl
index c6eb0d7915..a7980cc294 100644
--- a/lib/stdlib/src/lib.erl
+++ b/lib/stdlib/src/lib.erl
@@ -646,7 +646,7 @@ pp_arguments(PF, As, I, Enc) ->
             Ll = length(L),
             A = list_to_atom(lists:duplicate(Ll, $a)),
             S0 = unicode:characters_to_list(PF([A | T], I+1), Enc),
-            brackets_to_parens([$[,L,string:sub_string(S0, 2+Ll)], Enc);
+            brackets_to_parens([$[,L,string:slice(S0, 1+Ll)], Enc);
         _ -> 
             brackets_to_parens(PF(As, I+1), Enc)
     end.
diff --git a/lib/stdlib/src/maps.erl b/lib/stdlib/src/maps.erl
index 5dafdb282a..a13f340709 100644
--- a/lib/stdlib/src/maps.erl
+++ b/lib/stdlib/src/maps.erl
@@ -23,7 +23,8 @@
 -export([get/3, filter/2,fold/3,
          map/2, size/1,
          update_with/3, update_with/4,
-         without/2, with/2]).
+         without/2, with/2,
+         iterator/1, next/1]).
 
 %% BIFs
 -export([get/2, find/2, from_list/1,
@@ -31,6 +32,15 @@
          new/0, put/3, remove/2, take/2,
          to_list/1, update/3, values/1]).
 
+-opaque iterator() :: {term(), term(), iterator()}
+                      | none | nonempty_improper_list(integer(),map()).
+
+-export_type([iterator/0]).
+
+-dialyzer({no_improper_lists, iterator/1}).
+
+-define(IS_ITERATOR(I), is_tuple(I) andalso tuple_size(I) == 3; I == none; is_integer(hd(I)) andalso is_map(tl(I))).
+
 %% Shadowed by erl_bif_types: maps:get/2
 -spec get(Key,Map) -> Value when
     Key :: term(),
@@ -39,7 +49,6 @@
 
 get(_,_) -> erlang:nif_error(undef).
 
-
 -spec find(Key,Map) -> {ok, Value} | error when
     Key :: term(),
     Map :: map(),
@@ -114,14 +123,20 @@ remove(_,_) -> erlang:nif_error(undef).
 
 take(_,_) -> erlang:nif_error(undef).
 
-%% Shadowed by erl_bif_types: maps:to_list/1
 -spec to_list(Map) -> [{Key,Value}] when
     Map :: map(),
     Key :: term(),
     Value :: term().
 
-to_list(_) -> erlang:nif_error(undef).
+to_list(Map) when is_map(Map) ->
+    to_list_internal(erts_internal:map_next(0, Map, []));
+to_list(Map) ->
+    erlang:error({badmap,Map},[Map]).
 
+to_list_internal([Iter, Map | Acc]) when is_integer(Iter) ->
+    to_list_internal(erts_internal:map_next(Iter, Map, Acc));
+to_list_internal(Acc) ->
+    Acc.
 
 %% Shadowed by erl_bif_types: maps:update/3
 -spec update(Key,Value,Map1) -> Map2 when
@@ -192,47 +207,80 @@ get(Key,Map,Default) ->
     erlang:error({badmap,Map},[Key,Map,Default]).
 
 
--spec filter(Pred,Map1) -> Map2 when
+-spec filter(Pred,MapOrIter) -> Map when
       Pred :: fun((Key, Value) -> boolean()),
       Key  :: term(),
       Value :: term(),
-      Map1 :: map(),
-      Map2 :: map().
+      MapOrIter :: map() | iterator(),
+      Map :: map().
 
 filter(Pred,Map) when is_function(Pred,2), is_map(Map) ->
-    maps:from_list([{K,V}||{K,V}<-maps:to_list(Map),Pred(K,V)]);
+    maps:from_list(filter_1(Pred, iterator(Map)));
+filter(Pred,Iterator) when is_function(Pred,2), ?IS_ITERATOR(Iterator) ->
+    maps:from_list(filter_1(Pred, Iterator));
 filter(Pred,Map) ->
     erlang:error(error_type(Map),[Pred,Map]).
 
-
--spec fold(Fun,Init,Map) -> Acc when
+filter_1(Pred, Iter) ->
+    case next(Iter) of
+        {K, V, NextIter} ->
+            case Pred(K,V) of
+                true ->
+                    [{K,V} | filter_1(Pred, NextIter)];
+                false ->
+                    filter_1(Pred, NextIter)
+            end;
+        none ->
+            []
+    end.
+
+-spec fold(Fun,Init,MapOrIter) -> Acc when
     Fun :: fun((K, V, AccIn) -> AccOut),
     Init :: term(),
     Acc :: term(),
     AccIn :: term(),
     AccOut :: term(),
-    Map :: map(),
+    MapOrIter :: map() | iterator(),
     K :: term(),
     V :: term().
 
 fold(Fun,Init,Map) when is_function(Fun,3), is_map(Map) ->
-    lists:foldl(fun({K,V},A) -> Fun(K,V,A) end,Init,maps:to_list(Map));
+    fold_1(Fun,Init,iterator(Map));
+fold(Fun,Init,Iterator) when is_function(Fun,3), ?IS_ITERATOR(Iterator) ->
+    fold_1(Fun,Init,Iterator);
 fold(Fun,Init,Map) ->
     erlang:error(error_type(Map),[Fun,Init,Map]).
 
--spec map(Fun,Map1) -> Map2 when
+fold_1(Fun, Acc, Iter) ->
+    case next(Iter) of
+        {K, V, NextIter} ->
+            fold_1(Fun, Fun(K,V,Acc), NextIter);
+        none ->
+            Acc
+    end.
+
+-spec map(Fun,MapOrIter) -> Map when
     Fun :: fun((K, V1) -> V2),
-    Map1 :: map(),
-    Map2 :: map(),
+    MapOrIter :: map() | iterator(),
+    Map :: map(),
     K :: term(),
     V1 :: term(),
     V2 :: term().
 
 map(Fun,Map) when is_function(Fun, 2), is_map(Map) ->
-    maps:from_list([{K,Fun(K,V)}||{K,V}<-maps:to_list(Map)]);
+    maps:from_list(map_1(Fun, iterator(Map)));
+map(Fun,Iterator) when is_function(Fun, 2), ?IS_ITERATOR(Iterator) ->
+    maps:from_list(map_1(Fun, Iterator));
 map(Fun,Map) ->
     erlang:error(error_type(Map),[Fun,Map]).
 
+map_1(Fun, Iter) ->
+    case next(Iter) of
+        {K, V, NextIter} ->
+            [{K, Fun(K, V)} | map_1(Fun, NextIter)];
+        none ->
+            []
+    end.
 
 -spec size(Map) -> non_neg_integer() when
     Map :: map().
@@ -242,6 +290,26 @@ size(Map) when is_map(Map) ->
 size(Val) ->
     erlang:error({badmap,Val},[Val]).
 
+-spec iterator(Map) -> Iterator when
+      Map :: map(),
+      Iterator :: iterator().
+
+iterator(M) when is_map(M) -> [0 | M];
+iterator(M) -> erlang:error({badmap, M}, [M]).
+
+-spec next(Iterator) -> {Key, Value, NextIterator} | 'none' when
+      Iterator :: iterator(),
+      Key :: term(),
+      Value :: term(),
+      NextIterator :: iterator().
+next({K, V, I}) ->
+    {K, V, I};
+next([Path | Map]) when is_integer(Path), is_map(Map) ->
+    erts_internal:map_next(Path, Map, iterator);
+next(none) ->
+    none;
+next(Iter) ->
+    erlang:error(badarg, [Iter]).
 
 -spec without(Ks,Map1) -> Map2 when
     Ks :: [K],
@@ -250,11 +318,10 @@ size(Val) ->
     K :: term().
 
 without(Ks,M) when is_list(Ks), is_map(M) ->
-    lists:foldl(fun(K, M1) -> ?MODULE:remove(K, M1) end, M, Ks);
+    lists:foldl(fun(K, M1) -> maps:remove(K, M1) end, M, Ks);
 without(Ks,M) ->
     erlang:error(error_type(M),[Ks,M]).
 
-
 -spec with(Ks, Map1) -> Map2 when
     Ks :: [K],
     Map1 :: map(),
@@ -263,17 +330,17 @@ without(Ks,M) ->
 
 with(Ks,Map1) when is_list(Ks), is_map(Map1) ->
     Fun = fun(K, List) ->
-      case ?MODULE:find(K, Map1) of
-          {ok, V} ->
-              [{K, V} | List];
-          error ->
-              List
-      end
-    end,
-    ?MODULE:from_list(lists:foldl(Fun, [], Ks));
+                  case maps:find(K, Map1) of
+                      {ok, V} ->
+                          [{K, V} | List];
+                      error ->
+                          List
+                  end
+          end,
+    maps:from_list(lists:foldl(Fun, [], Ks));
 with(Ks,M) ->
     erlang:error(error_type(M),[Ks,M]).
 
 
-error_type(M) when is_map(M) -> badarg;
+error_type(M) when is_map(M); ?IS_ITERATOR(M) -> badarg;
 error_type(V) -> {badmap, V}.
diff --git a/lib/stdlib/src/otp_internal.erl b/lib/stdlib/src/otp_internal.erl
index 5b488cc677..122b476ddb 100644
--- a/lib/stdlib/src/otp_internal.erl
+++ b/lib/stdlib/src/otp_internal.erl
@@ -609,6 +609,52 @@ obsolete_1(filename, find_src, 2) ->
 obsolete_1(erlang, hash, 2) ->
     {removed, {erlang, phash2, 2}, "20.0"};
 
+%% Added in OTP-21
+obsolete_1(string, len, 1) ->
+    {deprecated, "deprecated; use string:length/3 instead"};
+obsolete_1(string, concat, 2) ->
+    {deprecated, "deprecated; use [Str1,Str2] instead"};
+obsolete_1(string, str, 2) ->
+    {deprecated, "deprecated; use string:find/2 instead"};
+obsolete_1(string, rstr, 2) ->
+    {deprecated, "deprecated; use string:find/3 instead"};
+obsolete_1(string, chr, 2) ->
+    {deprecated, "deprecated; use string:find/2 instead"};
+obsolete_1(string, rchr, 2) ->
+    {deprecated, "deprecated; use string:find/3 instead"};
+obsolete_1(string, span, 2) ->
+    {deprecated, "deprecated; use string:take/2 instead"};
+obsolete_1(string, cspan, 2) ->
+    {deprecated, "deprecated; use string:take/3 instead"};
+obsolete_1(string, substr, _) ->
+    {deprecated, "deprecated; use string:slice/3 instead"};
+obsolete_1(string, tokens, 2) ->
+    {deprecated, "deprecated; use string:lexemes/2 instead"};
+obsolete_1(string, chars, _) ->
+    {deprecated, "deprecated; use lists:duplicate/2 instead"};
+obsolete_1(string, copies, _) ->
+    {deprecated, "deprecated; use lists:duplicate/2 instead"};
+obsolete_1(string, words, _) ->
+    {deprecated, "deprecated; use string:lexemes/2 instead"};
+obsolete_1(string, strip, _) ->
+    {deprecated, "deprecated; use string:trim/3 instead"};
+obsolete_1(string, sub_word, _) ->
+    {deprecated, "deprecated; use string:nth_lexeme/3 instead"};
+obsolete_1(string, sub_string, _) ->
+    {deprecated, "deprecated; use string:slice/3 instead"};
+obsolete_1(string, left, _) ->
+    {deprecated, "deprecated; use string:pad/3 instead"};
+obsolete_1(string, right, _) ->
+    {deprecated, "deprecated; use string:pad/3 instead"};
+obsolete_1(string, centre, _) ->
+    {deprecated, "deprecated; use string:pad/3 instead"};
+obsolete_1(string, join, _) ->
+    {deprecated, "deprecated; use lists:join/2 instead"};
+obsolete_1(string, to_upper, _) ->
+    {deprecated, "deprecated; use string:uppercase/1 or string:titlecase/1 instead"};
+obsolete_1(string, to_lower, _) ->
+    {deprecated, "deprecated; use string:lowercase/1 or string:casefold/1 instead"};
+
 %% not obsolete
 
 obsolete_1(_, _, _) ->
diff --git a/lib/stdlib/src/pool.erl b/lib/stdlib/src/pool.erl
index 05950a1d7c..b12ff205b1 100644
--- a/lib/stdlib/src/pool.erl
+++ b/lib/stdlib/src/pool.erl
@@ -25,7 +25,7 @@
 %% with the least load !!!!
 %% This function is callable from any node including the master
 %% That is part of the pool
-%% nodes are scheduled on a per usgae basis and per load basis,
+%% nodes are scheduled on a per usage basis and per load basis,
 %% Whenever we use a node, we put at the end of the queue, and whenever
 %% a node report a change in load, we insert it accordingly
 
@@ -197,7 +197,7 @@ pure_insert({Load,Node},[{L,N}|Tail]) when Load < L ->
 pure_insert(L,[H|T]) -> [H|pure_insert(L,T)].
 
 %% Really should not measure the contributions from
-%% the back ground processes here .... which we do :-(
+%% the background processes here .... which we do :-(
 %% We don't have to monitor the master, since we're slaves anyway
 
 statistic_collector() ->
@@ -213,7 +213,7 @@ statistic_collector(I) ->
 	    stat_loop(M, 999999)
     end.
 
-%% Do not tell the master about our load if it has not  changed
+%% Do not tell the master about our load if it has not changed
 
 stat_loop(M, Old) ->
     sleep(2000),
diff --git a/lib/stdlib/src/rand.erl b/lib/stdlib/src/rand.erl
index 7a8a5e6d4a..362e98006e 100644
--- a/lib/stdlib/src/rand.erl
+++ b/lib/stdlib/src/rand.erl
@@ -21,8 +21,8 @@
 %% Multiple PRNG module for Erlang/OTP
 %% Copyright (c) 2015-2016 Kenji Rikitake
 %%
-%% exrop (xoroshiro116+) added and statistical distribution
-%% improvements by the Erlang/OTP team 2017
+%% exrop (xoroshiro116+) added, statistical distribution
+%% improvements and uniform_real added by the Erlang/OTP team 2017
 %% =====================================================================
 
 -module(rand).
@@ -30,10 +30,14 @@
 -export([seed_s/1, seed_s/2, seed/1, seed/2,
 	 export_seed/0, export_seed_s/1,
          uniform/0, uniform/1, uniform_s/1, uniform_s/2,
+         uniform_real/0, uniform_real_s/1,
          jump/0, jump/1,
 	     normal/0, normal/2, normal_s/1, normal_s/3
 	]).
 
+%% Debug
+-export([make_float/3, float2str/1, bc64/1]).
+
 -compile({inline, [exs64_next/1, exsplus_next/1,
 		   exs1024_next/1, exs1024_calc/2,
                    exrop_next/1, exrop_next_s/2,
@@ -60,6 +64,10 @@
    %% N i evaluated 3 times
    (?BSL((Bits), (X), (N)) bor ((X) bsr ((Bits)-(N))))).
 
+-define(
+   BC(V, N),
+   bc((V), ?BIT((N) - 1), N)).
+
 %%-define(TWO_POW_MINUS53, (math:pow(2, -53))).
 -define(TWO_POW_MINUS53, 1.11022302462515657e-16).
 
@@ -84,14 +92,21 @@
 %% The 'bits' field indicates how many bits the integer
 %% returned from 'next' has got, i.e 'next' shall return
 %% an random integer in the range 0..(2^Bits - 1).
-%% At least 53 bits is required for the floating point
-%% producing fallbacks.  This field is only used when
-%% the 'uniform' or 'uniform_n' fields are not defined.
+%% At least 55 bits is required for the floating point
+%% producing fallbacks, but 56 bits would be more future proof.
 %%
 %% The fields 'next', 'uniform' and 'uniform_n'
-%% implement the algorithm.  If 'uniform' or 'uinform_n'
+%% implement the algorithm.  If 'uniform' or 'uniform_n'
 %% is not present there is a fallback using 'next' and either
-%% 'bits' or the deprecated 'max'.
+%% 'bits' or the deprecated 'max'.  The 'next' function
+%% must generate a word with at least 56 good random bits.
+%%
+%% The 'weak_low_bits' field indicate how many bits are of
+%% lesser quality and they will not be used by the floating point
+%% producing functions, nor by the range producing functions
+%% when more bits are needed, to avoid weak bits in the middle
+%% of the generated bits.  The lowest bits from the range
+%% functions still have the generator's quality.
 %%
 -type alg_handler() ::
         #{type := alg(),
@@ -148,11 +163,7 @@
 
 %% For ranges larger than the algorithm bit size
 uniform_range(Range, #{next:=Next, bits:=Bits} = Alg, R, V) ->
-    WeakLowBits =
-        case Alg of
-            #{weak_low_bits:=WLB} -> WLB;
-            #{} -> 0
-        end,
+    WeakLowBits = maps:get(weak_low_bits, Alg, 0),
     %% Maybe waste the lowest bit(s) when shifting in new bits
     Shift = Bits - WeakLowBits,
     ShiftMask = bnot ?MASK(WeakLowBits),
@@ -297,7 +308,7 @@ uniform_s({#{bits:=Bits, next:=Next} = Alg, R0}) ->
     {(V bsr (Bits - 53)) * ?TWO_POW_MINUS53, {Alg, R1}};
 uniform_s({#{max:=Max, next:=Next} = Alg, R0}) ->
     {V, R1} = Next(R0),
-    %% Old broken algorithm with non-uniform density
+    %% Old algorithm with non-uniform density
     {V / (Max + 1), {Alg, R1}}.
 
 
@@ -317,7 +328,7 @@ uniform_s(N, {#{bits:=Bits, next:=Next} = Alg, R0})
     ?uniform_range(N, Alg, R1, V, MaxMinusN, I);
 uniform_s(N, {#{max:=Max, next:=Next} = Alg, R0})
   when is_integer(N), 1 =< N ->
-    %% Old broken algorithm with skewed probability
+    %% Old algorithm with skewed probability
     %% and gap in ranges > Max
     {V, R1} = Next(R0),  
     if
@@ -328,6 +339,189 @@ uniform_s(N, {#{max:=Max, next:=Next} = Alg, R0})
             {trunc(F * N) + 1, {Alg, R1}}
     end.
 
+%% uniform_real/0: returns a random float X where 0.0 < X =< 1.0,
+%% updating the state in the process dictionary.
+
+-spec uniform_real() -> X :: float().
+uniform_real() ->
+    {X, Seed} = uniform_real_s(seed_get()),
+    _ = seed_put(Seed),
+    X.
+
+%% uniform_real_s/1: given a state, uniform_s/1
+%% returns a random float X where 0.0 < X =< 1.0,
+%% and a new state.
+%%
+%% This function does not use the same form of uniformity
+%% as the uniform_s/1 function.
+%%
+%% Instead, this function does not generate numbers with equal
+%% distance in the interval, but rather tries to keep all mantissa
+%% bits random also for small numbers, meaning that the distance
+%% between possible numbers decreases when the numbers
+%% approaches 0.0, as does the possibility for a particular
+%% number.  Hence uniformity is preserved.
+%%
+%% To generate 56 bits at the time instead of 53 is actually
+%% a speed optimization since the probability to have to
+%% generate a second word decreases by 1/2 for every extra bit.
+%%
+%% This function generates normalized numbers, so the smallest number
+%% that can be generated is 2^-1022 with the distance 2^-1074
+%% to the next to smallest number, compared to 2^-53 for uniform_s/1.
+%%
+%% This concept of uniformity should work better for applications
+%% where you need to calculate 1.0/X or math:log(X) since those
+%% operations benefits from larger precision approaching 0.0,
+%% and that this function does not return 0.0 nor denormalized
+%% numbers very close to 0.0.  The log() operation in The Box-Muller
+%% transformation for normal distribution is an example of this.
+%%
+%%-define(TWO_POW_MINUS55, (math:pow(2, -55))).
+%%-define(TWO_POW_MINUS110, (math:pow(2, -110))).
+%%-define(TWO_POW_MINUS55, 2.7755575615628914e-17).
+%%-define(TWO_POW_MINUS110, 7.7037197775489436e-34).
+%%
+-spec uniform_real_s(State :: state()) -> {X :: float(), NewState :: state()}.
+uniform_real_s({#{bits:=Bits, next:=Next} = Alg, R0}) ->
+    %% Generate a 56 bit number without using the weak low bits.
+    %%
+    %% Be sure to use only 53 bits when multiplying with
+    %% math:pow(2.0, -N) to avoid rounding which would make
+    %% "even" floats more probable than "odd".
+    %%
+    {V1, R1} = Next(R0),
+    M1 = V1 bsr (Bits - 56),
+    if
+        ?BIT(55) =< M1 ->
+            %% We have 56 bits - waste 3
+            {(M1 bsr 3) * math:pow(2.0, -53), {Alg, R1}};
+        ?BIT(54) =< M1 ->
+            %% We have 55 bits - waste 2
+            {(M1 bsr 2) * math:pow(2.0, -54), {Alg, R1}};
+        ?BIT(53) =< M1 ->
+            %% We have 54 bits - waste 1
+            {(M1 bsr 1) * math:pow(2.0, -55), {Alg, R1}};
+        ?BIT(52) =< M1 ->
+            %% We have 53 bits - use all
+            {M1 * math:pow(2.0, -56), {Alg, R1}};
+        true ->
+            %% Need more bits
+            {V2, R2} = Next(R1),
+            uniform_real_s(Alg, Next, M1, -56, R2, V2, Bits)
+    end;
+uniform_real_s({#{max:=_, next:=Next} = Alg, R0}) ->
+    %% Generate a 56 bit number.
+    %% Ignore the weak low bits for these old algorithms,
+    %% just produce something reasonable.
+    %%
+    %% Be sure to use only 53 bits when multiplying with
+    %% math:pow(2.0, -N) to avoid rounding which would make
+    %% "even" floats more probable than "odd".
+    %%
+    {V1, R1} = Next(R0),
+    M1 = ?MASK(56, V1),
+    if
+        ?BIT(55) =< M1 ->
+            %% We have 56 bits - waste 3
+            {(M1 bsr 3) * math:pow(2.0, -53), {Alg, R1}};
+        ?BIT(54) =< M1 ->
+            %% We have 55 bits - waste 2
+            {(M1 bsr 2) * math:pow(2.0, -54), {Alg, R1}};
+        ?BIT(53) =< M1 ->
+            %% We have 54 bits - waste 1
+            {(M1 bsr 1) * math:pow(2.0, -55), {Alg, R1}};
+        ?BIT(52) =< M1 ->
+            %% We have 53 bits - use all
+            {M1 * math:pow(2.0, -56), {Alg, R1}};
+        true ->
+            %% Need more bits
+            {V2, R2} = Next(R1),
+            uniform_real_s(Alg, Next, M1, -56, R2, V2, 56)
+    end.
+
+uniform_real_s(Alg, _Next, M0, -1064, R1, V1, Bits) -> % 19*56
+    %% This is a very theoretical bottom case.
+    %% The odds of getting here is about 2^-1008,
+    %% through a white box test case, or thanks to
+    %% a malfunctioning PRNG producing 18 56-bit zeros in a row.
+    %%
+    %% Fill up to 53 bits, we have at most 52
+    B0 = (53 - ?BC(M0, 52)), % Missing bits
+    {(((M0 bsl B0) bor (V1 bsr (Bits - B0))) * math:pow(2.0, -1064 - B0)),
+     {Alg, R1}};
+uniform_real_s(Alg, Next, M0, BitNo, R1, V1, Bits) ->
+    if
+        %% Optimize the most probable.
+        %% Fill up to 53 bits.
+        ?BIT(51) =< M0 ->
+            %% We have 52 bits in M0 - need 1
+            {(((M0 bsl 1) bor (V1 bsr (Bits - 1)))
+              * math:pow(2.0, BitNo - 1)),
+             {Alg, R1}};
+        ?BIT(50) =< M0 ->
+            %% We have 51 bits in M0 - need 2
+            {(((M0 bsl 2) bor (V1 bsr (Bits - 2)))
+              * math:pow(2.0, BitNo - 2)),
+             {Alg, R1}};
+        ?BIT(49) =< M0 ->
+            %% We have 50 bits in M0 - need 3
+            {(((M0 bsl 3) bor (V1 bsr (Bits - 3)))
+              * math:pow(2.0, BitNo - 3)),
+             {Alg, R1}};
+        M0 == 0 ->
+            M1 = V1 bsr (Bits - 56),
+            if
+                ?BIT(55) =< M1 ->
+                    %% We have 56 bits - waste 3
+                    {(M1 bsr 3) * math:pow(2.0, BitNo - 53), {Alg, R1}};
+                ?BIT(54) =< M1 ->
+                    %% We have 55 bits - waste 2
+                    {(M1 bsr 2) * math:pow(2.0, BitNo - 54), {Alg, R1}};
+                ?BIT(53) =< M1 ->
+                    %% We have 54 bits - waste 1
+                    {(M1 bsr 1) * math:pow(2.0, BitNo - 55), {Alg, R1}};
+                ?BIT(52) =< M1 ->
+                    %% We have 53 bits - use all
+                    {M1 * math:pow(2.0, BitNo - 56), {Alg, R1}};
+                BitNo =:= -1008 ->
+                    %% Endgame
+                    %% For the last round we can not have 14 zeros or more
+                    %% at the top of M1 because then we will underflow,
+                    %% so we need at least 43 bits
+                    if
+                        ?BIT(42) =< M1 ->
+                            %% We have 43 bits - get the last bits
+                            uniform_real_s(Alg, Next, M1, BitNo - 56, R1);
+                        true ->
+                            %% Would underflow 2^-1022 - start all over
+                            %%
+                            %% We could just crash here since the odds for
+                            %% the PRNG being broken is much higher than
+                            %% for a good PRNG generating this many zeros
+                            %% in a row.  Maybe we should write an error
+                            %% report or call this a system limit...?
+                            uniform_real_s({Alg, R1})
+                    end;
+                true ->
+                    %% Need more bits
+                    uniform_real_s(Alg, Next, M1, BitNo - 56, R1)
+            end;
+        true ->
+            %% Fill up to 53 bits
+            B0 = 53 - ?BC(M0, 49), % Number of bits we need to append
+            {(((M0 bsl B0) bor (V1 bsr (Bits - B0)))
+              * math:pow(2.0, BitNo - B0)),
+             {Alg, R1}}
+    end.
+%%
+uniform_real_s(#{bits:=Bits} = Alg, Next, M0, BitNo, R0) ->
+    {V1, R1} = Next(R0),
+    uniform_real_s(Alg, Next, M0, BitNo, R1, V1, Bits);
+uniform_real_s(#{max:=_} = Alg, Next, M0, BitNo, R0) ->
+    {V1, R1} = Next(R0),
+    uniform_real_s(Alg, Next, M0, BitNo, R1, ?MASK(56, V1), 56).
+
 %% jump/1: given a state, jump/1
 %% returns a new state which is equivalent to that
 %% after a large number of call defined for each algorithm.
@@ -1025,3 +1219,42 @@ normal_fi(Indx) ->
 	     1.0214971439701471e-02,8.6165827693987316e-03,7.0508754713732268e-03,
 	     5.5224032992509968e-03,4.0379725933630305e-03,2.6090727461021627e-03,
 	     1.2602859304985975e-03}).
+
+%%%bitcount64(0) -> 0;
+%%%bitcount64(V) -> 1 + bitcount(V, 64).
+%%%
+%%%-define(
+%%%   BITCOUNT(V, N),
+%%%   bitcount(V, N) ->
+%%%       if
+%%%           (1 bsl ((N) bsr 1)) =< (V) ->
+%%%               ((N) bsr 1) + bitcount((V) bsr ((N) bsr 1), ((N) bsr 1));
+%%%           true ->
+%%%               bitcount((V), ((N) bsr 1))
+%%%       end).
+%%%?BITCOUNT(V, 64);
+%%%?BITCOUNT(V, 32);
+%%%?BITCOUNT(V, 16);
+%%%?BITCOUNT(V, 8);
+%%%?BITCOUNT(V, 4);
+%%%?BITCOUNT(V, 2);
+%%%bitcount(_, 1) -> 0.
+
+bc64(V) -> ?BC(V, 64).
+
+%% Linear from high bit - higher probability first gives faster execution
+bc(V, B, N) when B =< V -> N;
+bc(V, B, N) -> bc(V, B bsr 1, N - 1).
+    
+make_float(S, E, M) ->
+    <<F/float>> = <<S:1, E:11, M:52>>,
+    F.
+
+float2str(N) ->
+    <<S:1, E:11, M:52>> = <<(float(N))/float>>,
+    lists:flatten(
+      io_lib:format(
+      "~c~c.~13.16.0bE~b",
+      [case S of 1 -> $-; 0 -> $+ end,
+       case E of 0 -> $0; _ -> $1 end,
+       M, E - 16#3ff])).
diff --git a/lib/stdlib/src/slave.erl b/lib/stdlib/src/slave.erl
index d7cf6386f5..b3f3206d67 100644
--- a/lib/stdlib/src/slave.erl
+++ b/lib/stdlib/src/slave.erl
@@ -320,7 +320,7 @@ mk_cmd(Host, Name, Args, Waiter, Prog0) ->
 %% emulator and flags as the test node. The return from lib:progname()
 %% could then typically be '/<full_path_to>/cerl -gcov').
 quote_progname(Progname) ->
-    do_quote_progname(string:tokens(to_list(Progname)," ")).
+    do_quote_progname(string:lexemes(to_list(Progname)," ")).
 
 do_quote_progname([Prog]) ->
     "\""++Prog++"\"";
diff --git a/lib/stdlib/src/stdlib.app.src b/lib/stdlib/src/stdlib.app.src
index 3c449d3cb9..5fb48acfab 100644
--- a/lib/stdlib/src/stdlib.app.src
+++ b/lib/stdlib/src/stdlib.app.src
@@ -101,13 +101,14 @@
 	     timer,
 	     unicode,
              unicode_util,
+	     uri_string,
 	     win32reg,
 	     zip]},
   {registered,[timer_server,rsh_starter,take_over_monitor,pool_master,
                dets]},
   {applications, [kernel]},
   {env, []},
-  {runtime_dependencies, ["sasl-3.0","kernel-5.0","erts-9.0","crypto-3.3",
+  {runtime_dependencies, ["sasl-3.0","kernel-6.0","erts-10.0","crypto-3.3",
 			  "compiler-5.0"]}
 ]}.
 
diff --git a/lib/stdlib/src/stdlib.appup.src b/lib/stdlib/src/stdlib.appup.src
index 800c2c61f3..e4e3fb83e9 100644
--- a/lib/stdlib/src/stdlib.appup.src
+++ b/lib/stdlib/src/stdlib.appup.src
@@ -18,9 +18,7 @@
 %% %CopyrightEnd%
 {"%VSN%",
  %% Up from - max one major revision back
- [{<<"3\\.[0-3](\\.[0-9]+)*">>,[restart_new_emulator]}, % OTP-19.*
-  {<<"3\\.4(\\.[0-9]+)*">>,[restart_new_emulator]}],    % OTP-20.*
+ [{<<"3\\.4(\\.[0-9]+)*">>,[restart_new_emulator]}], % OTP-20.*
  %% Down to - max one major revision back
- [{<<"3\\.[0-3](\\.[0-9]+)*">>,[restart_new_emulator]}, % OTP-19.*
-  {<<"3\\.4(\\.[0-9]+)*">>,[restart_new_emulator]}]     % OTP-20.*
+ [{<<"3\\.4(\\.[0-9]+)*">>,[restart_new_emulator]}]  % OTP-20.*
 }.
diff --git a/lib/stdlib/src/string.erl b/lib/stdlib/src/string.erl
index ab041ff53c..e01bb7d85e 100644
--- a/lib/stdlib/src/string.erl
+++ b/lib/stdlib/src/string.erl
@@ -88,6 +88,15 @@
 %%% May be removed
 -export([list_to_float/1, list_to_integer/1]).
 
+-deprecated([{len,1},{concat,2},
+             {str,2},{chr,2},{rchr,2},{rstr,2},
+             {span,2},{cspan,2},{substr,'_'},{tokens,2},
+             {chars,'_'},
+             {copies,2},{words,'_'},{strip,'_'},
+             {sub_word,'_'},{left,'_'},{right,'_'},
+             {sub_string,'_'},{centre,'_'},{join,2},
+             {to_upper,1}, {to_lower,1}
+            ]).
 
 %% Uses bifs: string:list_to_float/1 and string:list_to_integer/1
 -spec list_to_float(String) -> {Float, Rest} | {'error', Reason} when
diff --git a/lib/stdlib/src/supervisor.erl b/lib/stdlib/src/supervisor.erl
index 7920e55930..e56415650f 100644
--- a/lib/stdlib/src/supervisor.erl
+++ b/lib/stdlib/src/supervisor.erl
@@ -31,7 +31,6 @@
 %% Internal exports
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
 	 terminate/2, code_change/3, format_status/2]).
--export([try_again_restart/2]).
 
 %% For release_handler only
 -export([get_callback_module/1]).
@@ -79,6 +78,7 @@
                    | {RestartStrategy :: strategy(),
                       Intensity :: non_neg_integer(),
                       Period :: pos_integer()}.
+-type children() :: {Ids :: [child_id()], Db :: #{child_id() => child_rec()}}.
 
 %%--------------------------------------------------------------------------
 %% Defaults
@@ -96,7 +96,7 @@
 	        pid = undefined :: child()
 	                         | {restarting, pid() | undefined}
 	                         | [pid()],
-		name            :: child_id(),
+		id              :: child_id(),
 		mfargs          :: mfargs(),
 		restart_type    :: restart(),
 		shutdown        :: shutdown(),
@@ -104,16 +104,11 @@
 		modules = []    :: modules()}).
 -type child_rec() :: #child{}.
 
--define(DICTS, dict).
--define(DICT, dict:dict).
--define(SETS, sets).
--define(SET, sets:set).
-
 -record(state, {name,
 		strategy               :: strategy() | 'undefined',
-		children = []          :: [child_rec()],
-                dynamics               :: {'dict', ?DICT(pid(), list())}
-                                        | {'set', ?SET(pid())}
+		children = {[],#{}}    :: children(), % Ids in start order
+                dynamics               :: {'maps', #{pid() => list()}}
+                                        | {'sets', sets:set(pid())}
                                         | 'undefined',
 		intensity              :: non_neg_integer() | 'undefined',
 		period                 :: pos_integer() | 'undefined',
@@ -124,6 +119,9 @@
 -type state() :: #state{}.
 
 -define(is_simple(State), State#state.strategy =:= simple_one_for_one).
+-define(is_temporary(_Child_), _Child_#child.restart_type=:=temporary).
+-define(is_transient(_Child_), _Child_#child.restart_type=:=transient).
+-define(is_permanent(_Child_), _Child_#child.restart_type=:=permanent).
 
 -callback init(Args :: term()) ->
     {ok, {SupFlags :: sup_flags(), [ChildSpec :: child_spec()]}}
@@ -179,16 +177,16 @@ start_child(Supervisor, ChildSpec) ->
               | {'error', Error},
       Error :: 'running' | 'restarting' | 'not_found' | 'simple_one_for_one' |
 	       term().
-restart_child(Supervisor, Name) ->
-    call(Supervisor, {restart_child, Name}).
+restart_child(Supervisor, Id) ->
+    call(Supervisor, {restart_child, Id}).
 
 -spec delete_child(SupRef, Id) -> Result when
       SupRef :: sup_ref(),
       Id :: child_id(),
       Result :: 'ok' | {'error', Error},
       Error :: 'running' | 'restarting' | 'not_found' | 'simple_one_for_one'.
-delete_child(Supervisor, Name) ->
-    call(Supervisor, {delete_child, Name}).
+delete_child(Supervisor, Id) ->
+    call(Supervisor, {delete_child, Id}).
 
 %%-----------------------------------------------------------------
 %% Func: terminate_child/2
@@ -202,16 +200,16 @@ delete_child(Supervisor, Name) ->
       Id :: pid() | child_id(),
       Result :: 'ok' | {'error', Error},
       Error :: 'not_found' | 'simple_one_for_one'.
-terminate_child(Supervisor, Name) ->
-    call(Supervisor, {terminate_child, Name}).
+terminate_child(Supervisor, Id) ->
+    call(Supervisor, {terminate_child, Id}).
 
 -spec get_childspec(SupRef, Id) -> Result when
       SupRef :: sup_ref(),
       Id :: pid() | child_id(),
       Result :: {'ok', child_spec()} | {'error', Error},
       Error :: 'not_found'.
-get_childspec(Supervisor, Name) ->
-    call(Supervisor, {get_childspec, Name}).
+get_childspec(Supervisor, Id) ->
+    call(Supervisor, {get_childspec, Id}).
 
 -spec which_children(SupRef) -> [{Id,Child,Type,Modules}] when
       SupRef :: sup_ref(),
@@ -246,17 +244,6 @@ check_childspecs(ChildSpecs) when is_list(ChildSpecs) ->
 check_childspecs(X) -> {error, {badarg, X}}.
 
 %%%-----------------------------------------------------------------
-%%% Called by restart/2
--spec try_again_restart(SupRef, Child) -> ok when
-      SupRef :: sup_ref(),
-      Child :: child_id() | pid().
-try_again_restart(Supervisor, Child) ->
-    cast(Supervisor, {try_again_restart, Child}).
-
-cast(Supervisor, Req) ->
-    gen_server:cast(Supervisor, Req).
-
-%%%-----------------------------------------------------------------
 %%% Called by release_handler during upgrade
 -spec get_callback_module(Pid) -> Module when
       Pid :: pid(),
@@ -325,7 +312,7 @@ init_children(State, StartSpec) ->
 init_dynamic(State, [StartSpec]) ->
     case check_startspec([StartSpec]) of
         {ok, Children} ->
-	    {ok, State#state{children = Children}};
+	    {ok, dyn_init(State#state{children = Children})};
         Error ->
             {stop, {start_spec, Error}}
     end;
@@ -334,35 +321,34 @@ init_dynamic(_State, StartSpec) ->
 
 %%-----------------------------------------------------------------
 %% Func: start_children/2
-%% Args: Children = [child_rec()] in start order
+%% Args: Children = children() % Ids in start order
 %%       SupName = {local, atom()} | {global, atom()} | {pid(), Mod}
-%% Purpose: Start all children.  The new list contains #child's
+%% Purpose: Start all children.  The new map contains #child's
 %%          with pids.
 %% Returns: {ok, NChildren} | {error, NChildren, Reason}
-%%          NChildren = [child_rec()] in termination order (reversed
-%%                        start order)
+%%          NChildren = children() % Ids in termination order
+%%                                   (reversed start order)
 %%-----------------------------------------------------------------
-start_children(Children, SupName) -> start_children(Children, [], SupName).
-
-start_children([Child|Chs], NChildren, SupName) ->
-    case do_start_child(SupName, Child) of
-	{ok, undefined} when Child#child.restart_type =:= temporary ->
-	    start_children(Chs, NChildren, SupName);
-	{ok, Pid} ->
-	    start_children(Chs, [Child#child{pid = Pid}|NChildren], SupName);
-	{ok, Pid, _Extra} ->
-	    start_children(Chs, [Child#child{pid = Pid}|NChildren], SupName);
-	{error, Reason} ->
-	    report_error(start_error, Reason, Child, SupName),
-	    {error, lists:reverse(Chs) ++ [Child | NChildren],
-	     {failed_to_start_child,Child#child.name,Reason}}
-    end;
-start_children([], NChildren, _SupName) ->
-    {ok, NChildren}.
+start_children(Children, SupName) ->
+    Start =
+        fun(Id,Child) ->
+                case do_start_child(SupName, Child) of
+                    {ok, undefined} when ?is_temporary(Child) ->
+                        remove;
+                    {ok, Pid} ->
+                        {update,Child#child{pid = Pid}};
+                    {ok, Pid, _Extra} ->
+                        {update,Child#child{pid = Pid}};
+                    {error, Reason} ->
+                        report_error(start_error, Reason, Child, SupName),
+                        {abort,{failed_to_start_child,Id,Reason}}
+                end
+        end,
+    children_map(Start,Children).
 
 do_start_child(SupName, Child) ->
     #child{mfargs = {M, F, Args}} = Child,
-    case catch apply(M, F, Args) of
+    case do_start_child_i(M, F, Args) of
 	{ok, Pid} when is_pid(Pid) ->
 	    NChild = Child#child{pid = Pid},
 	    report_progress(NChild, SupName),
@@ -371,10 +357,8 @@ do_start_child(SupName, Child) ->
 	    NChild = Child#child{pid = Pid},
 	    report_progress(NChild, SupName),
 	    {ok, Pid, Extra};
-	ignore ->
-	    {ok, undefined};
-	{error, What} -> {error, What};
-	What -> {error, What}
+        Other ->
+            Other
     end.
 
 do_start_child_i(M, F, A) ->
@@ -400,17 +384,17 @@ do_start_child_i(M, F, A) ->
 -spec handle_call(call(), term(), state()) -> {'reply', term(), state()}.
 
 handle_call({start_child, EArgs}, _From, State) when ?is_simple(State) ->
-    Child = hd(State#state.children),
+    Child = get_dynamic_child(State),
     #child{mfargs = {M, F, A}} = Child,
     Args = A ++ EArgs,
     case do_start_child_i(M, F, Args) of
 	{ok, undefined} ->
 	    {reply, {ok, undefined}, State};
 	{ok, Pid} ->
-	    NState = save_dynamic_child(Child#child.restart_type, Pid, Args, State),
+	    NState = dyn_store(Pid, Args, State),
 	    {reply, {ok, Pid}, NState};
 	{ok, Pid, Extra} ->
-	    NState = save_dynamic_child(Child#child.restart_type, Pid, Args, State),
+	    NState = dyn_store(Pid, Args, State),
 	    {reply, {ok, Pid, Extra}, NState};
 	What ->
 	    {reply, What, State}
@@ -426,121 +410,94 @@ handle_call({start_child, ChildSpec}, _From, State) ->
     end;
 
 %% terminate_child for simple_one_for_one can only be done with pid
-handle_call({terminate_child, Name}, _From, State) when not is_pid(Name),
-							?is_simple(State) ->
+handle_call({terminate_child, Id}, _From, State) when not is_pid(Id),
+                                                      ?is_simple(State) ->
     {reply, {error, simple_one_for_one}, State};
 
-handle_call({terminate_child, Name}, _From, State) ->
-    case get_child(Name, State, ?is_simple(State)) of
-	{value, Child} ->
-	    case do_terminate(Child, State#state.name) of
-		#child{restart_type=RT} when RT=:=temporary; ?is_simple(State) ->
-		    {reply, ok, state_del_child(Child, State)};
-		NChild ->
-		    {reply, ok, replace_child(NChild, State)}
-		end;
-	false ->
+handle_call({terminate_child, Id}, _From, State) ->
+    case find_child(Id, State) of
+	{ok, Child} ->
+	    do_terminate(Child, State#state.name),
+            {reply, ok, del_child(Child, State)};
+	error ->
 	    {reply, {error, not_found}, State}
     end;
 
 %% restart_child request is invalid for simple_one_for_one supervisors
-handle_call({restart_child, _Name}, _From, State) when ?is_simple(State) ->
+handle_call({restart_child, _Id}, _From, State) when ?is_simple(State) ->
     {reply, {error, simple_one_for_one}, State};
 
-handle_call({restart_child, Name}, _From, State) ->
-    case get_child(Name, State) of
-	{value, Child} when Child#child.pid =:= undefined ->
+handle_call({restart_child, Id}, _From, State) ->
+    case find_child(Id, State) of
+	{ok, Child} when Child#child.pid =:= undefined ->
 	    case do_start_child(State#state.name, Child) of
 		{ok, Pid} ->
-		    NState = replace_child(Child#child{pid = Pid}, State),
+		    NState = set_pid(Pid, Id, State),
 		    {reply, {ok, Pid}, NState};
 		{ok, Pid, Extra} ->
-		    NState = replace_child(Child#child{pid = Pid}, State),
+		    NState = set_pid(Pid, Id, State),
 		    {reply, {ok, Pid, Extra}, NState};
 		Error ->
 		    {reply, Error, State}
 	    end;
-	{value, #child{pid=?restarting(_)}} ->
+	{ok, #child{pid=?restarting(_)}} ->
 	    {reply, {error, restarting}, State};
-	{value, _} ->
+	{ok, _} ->
 	    {reply, {error, running}, State};
 	_ ->
 	    {reply, {error, not_found}, State}
     end;
 
 %% delete_child request is invalid for simple_one_for_one supervisors
-handle_call({delete_child, _Name}, _From, State) when ?is_simple(State) ->
+handle_call({delete_child, _Id}, _From, State) when ?is_simple(State) ->
     {reply, {error, simple_one_for_one}, State};
 
-handle_call({delete_child, Name}, _From, State) ->
-    case get_child(Name, State) of
-	{value, Child} when Child#child.pid =:= undefined ->
-	    NState = remove_child(Child, State),
+handle_call({delete_child, Id}, _From, State) ->
+    case find_child(Id, State) of
+	{ok, Child} when Child#child.pid =:= undefined ->
+	    NState = remove_child(Id, State),
 	    {reply, ok, NState};
-	{value, #child{pid=?restarting(_)}} ->
+	{ok, #child{pid=?restarting(_)}} ->
 	    {reply, {error, restarting}, State};
-	{value, _} ->
+	{ok, _} ->
 	    {reply, {error, running}, State};
 	_ ->
 	    {reply, {error, not_found}, State}
     end;
 
-handle_call({get_childspec, Name}, _From, State) ->
-    case get_child(Name, State, ?is_simple(State)) of
-	{value, Child} ->
+handle_call({get_childspec, Id}, _From, State) ->
+    case find_child(Id, State) of
+	{ok, Child} ->
             {reply, {ok, child_to_spec(Child)}, State};
-	false ->
+	error ->
 	    {reply, {error, not_found}, State}
     end;
 
-handle_call(which_children, _From, #state{children = [#child{restart_type = temporary,
-							     child_type = CT,
-							     modules = Mods}]} =
-		State) when ?is_simple(State) ->
-    Reply = lists:map(fun(Pid) -> {undefined, Pid, CT, Mods} end,
-                      ?SETS:to_list(dynamics_db(temporary, State#state.dynamics))),
-    {reply, Reply, State};
-
-handle_call(which_children, _From, #state{children = [#child{restart_type = RType,
-							 child_type = CT,
-							 modules = Mods}]} =
-		State) when ?is_simple(State) ->
-    Reply = lists:map(fun({?restarting(_),_}) -> {undefined,restarting,CT,Mods};
-			 ({Pid, _}) -> {undefined, Pid, CT, Mods} end,
-		      ?DICTS:to_list(dynamics_db(RType, State#state.dynamics))),
+handle_call(which_children, _From, State) when ?is_simple(State) ->
+    #child{child_type = CT,modules = Mods} = get_dynamic_child(State),
+    Reply = dyn_map(fun(?restarting(_)) -> {undefined, restarting, CT, Mods};
+                       (Pid) -> {undefined, Pid, CT, Mods}
+                    end, State),
     {reply, Reply, State};
 
 handle_call(which_children, _From, State) ->
     Resp =
-	lists:map(fun(#child{pid = ?restarting(_), name = Name,
-			     child_type = ChildType, modules = Mods}) ->
-			  {Name, restarting, ChildType, Mods};
-		     (#child{pid = Pid, name = Name,
-			     child_type = ChildType, modules = Mods}) ->
-			  {Name, Pid, ChildType, Mods}
-		  end,
-		  State#state.children),
+	children_to_list(
+          fun(Id,#child{pid = ?restarting(_),
+                        child_type = ChildType, modules = Mods}) ->
+                  {Id, restarting, ChildType, Mods};
+             (Id,#child{pid = Pid,
+                        child_type = ChildType, modules = Mods}) ->
+                  {Id, Pid, ChildType, Mods}
+          end,
+          State#state.children),
     {reply, Resp, State};
 
-
-handle_call(count_children, _From, #state{children = [#child{restart_type = temporary,
-							     child_type = CT}]} = State)
-  when ?is_simple(State) ->
-    Sz = ?SETS:size(dynamics_db(temporary, State#state.dynamics)),
-    Reply = case CT of
-		supervisor -> [{specs, 1}, {active, Sz},
-			       {supervisors, Sz}, {workers, 0}];
-		worker -> [{specs, 1}, {active, Sz},
-			   {supervisors, 0}, {workers, Sz}]
-	    end,
-    {reply, Reply, State};
-
-handle_call(count_children, _From,  #state{dynamic_restarts = Restarts,
-					   children = [#child{restart_type = RType,
-							      child_type = CT}]} = State)
+handle_call(count_children, _From,  #state{dynamic_restarts = Restarts} = State)
   when ?is_simple(State) ->
-    Sz = ?DICTS:size(dynamics_db(RType, State#state.dynamics)),
-    Active = Sz - Restarts,
+    #child{child_type = CT} = get_dynamic_child(State),
+    Sz = dyn_size(State),
+    Active = Sz - Restarts, % Restarts is always 0 for temporary children
     Reply = case CT of
 		supervisor -> [{specs, 1}, {active, Active},
 			       {supervisors, Sz}, {workers, 0}];
@@ -552,16 +509,15 @@ handle_call(count_children, _From,  #state{dynamic_restarts = Restarts,
 handle_call(count_children, _From, State) ->
     %% Specs and children are together on the children list...
     {Specs, Active, Supers, Workers} =
-	lists:foldl(fun(Child, Counts) ->
-			   count_child(Child, Counts)
-		   end, {0,0,0,0}, State#state.children),
+	children_fold(fun(_Id, Child, Counts) ->
+                              count_child(Child, Counts)
+                      end, {0,0,0,0}, State#state.children),
 
     %% Reformat counts to a property list.
     Reply = [{specs, Specs}, {active, Active},
 	     {supervisors, Supers}, {workers, Workers}],
     {reply, Reply, State}.
 
-
 count_child(#child{pid = Pid, child_type = worker},
 	    {Specs, Active, Supers, Workers}) ->
     case is_pid(Pid) andalso is_process_alive(Pid) of
@@ -575,34 +531,15 @@ count_child(#child{pid = Pid, child_type = supervisor},
 	false -> {Specs+1, Active, Supers+1, Workers}
     end.
 
-
 %%% If a restart attempt failed, this message is cast
 %%% from restart/2 in order to give gen_server the chance to
 %%% check it's inbox before trying again.
--spec handle_cast({try_again_restart, child_id() | pid()}, state()) ->
+-spec handle_cast({try_again_restart, child_id() | {'restarting',pid()}}, state()) ->
 			 {'noreply', state()} | {stop, shutdown, state()}.
 
-handle_cast({try_again_restart,Pid}, #state{children=[Child]}=State)
-  when ?is_simple(State) ->
-    RT = Child#child.restart_type,
-    RPid = restarting(Pid),
-    case dynamic_child_args(RPid, RT, State#state.dynamics) of
-	{ok, Args} ->
-	    {M, F, _} = Child#child.mfargs,
-	    NChild = Child#child{pid = RPid, mfargs = {M, F, Args}},
-	    case restart(NChild,State) of
-		{ok, State1} ->
-		    {noreply, State1};
-		{shutdown, State1} ->
-		    {stop, shutdown, State1}
-	    end;
-	error ->
-            {noreply, State}
-    end;
-
-handle_cast({try_again_restart,Name}, State) ->
-    case lists:keyfind(Name,#child.name,State#state.children) of
-	Child = #child{pid=?restarting(_)} ->
+handle_cast({try_again_restart,TryAgainId}, State) ->
+    case find_child_and_args(TryAgainId, State) of
+	{ok, Child = #child{pid=?restarting(_)}} ->
 	    case restart(Child,State) of
 		{ok, State1} ->
 		    {noreply, State1};
@@ -637,10 +574,8 @@ handle_info(Msg, State) ->
 %%
 -spec terminate(term(), state()) -> 'ok'.
 
-terminate(_Reason, #state{children=[Child]} = State) when ?is_simple(State) ->
-    terminate_dynamic_children(Child, dynamics_db(Child#child.restart_type,
-                                                  State#state.dynamics),
-                               State#state.name);
+terminate(_Reason, State) when ?is_simple(State) ->
+    terminate_dynamic_children(State);
 terminate(_Reason, State) ->
     terminate_children(State#state.children, State#state.name).
 
@@ -675,8 +610,8 @@ code_change(_, State, _) ->
 
 update_childspec(State, StartSpec) when ?is_simple(State) ->
     case check_startspec(StartSpec) of
-        {ok, [Child]} ->
-            {ok, State#state{children = [Child]}};
+        {ok, {[_],_}=Children} ->
+            {ok, State#state{children = Children}};
         Error ->
             {error, Error}
     end;
@@ -690,39 +625,36 @@ update_childspec(State, StartSpec) ->
 	    {error, Error}
     end.
 
-update_childspec1([Child|OldC], Children, KeepOld) ->
-    case update_chsp(Child, Children) of
-	{ok,NewChildren} ->
-	    update_childspec1(OldC, NewChildren, KeepOld);
+update_childspec1({[Id|OldIds], OldDb}, {Ids,Db}, KeepOld) ->
+    case update_chsp(maps:get(Id,OldDb), Db) of
+	{ok,NewDb} ->
+	    update_childspec1({OldIds,OldDb}, {Ids,NewDb}, KeepOld);
 	false ->
-	    update_childspec1(OldC, Children, [Child|KeepOld])
+	    update_childspec1({OldIds,OldDb}, {Ids,Db}, [Id|KeepOld])
     end;
-update_childspec1([], Children, KeepOld) ->
+update_childspec1({[],OldDb}, {Ids,Db}, KeepOld) ->
+    KeepOldDb = maps:with(KeepOld,OldDb),
     %% Return them in (kept) reverse start order.
-    lists:reverse(Children ++ KeepOld).
-
-update_chsp(OldCh, Children) ->
-    case lists:map(fun(Ch) when OldCh#child.name =:= Ch#child.name ->
-			   Ch#child{pid = OldCh#child.pid};
-		      (Ch) ->
-			   Ch
-		   end,
-		   Children) of
-	Children ->
-	    false;  % OldCh not found in new spec.
-	NewC ->
-	    {ok, NewC}
+    {lists:reverse(Ids ++ KeepOld),maps:merge(KeepOldDb,Db)}.
+
+update_chsp(#child{id=Id}=OldChild, NewDb) ->
+    case maps:find(Id, NewDb) of
+        {ok,Child} ->
+            {ok,NewDb#{Id => Child#child{pid = OldChild#child.pid}}};
+        error -> % Id not found in new spec.
+            false
     end.
+
     
 %%% ---------------------------------------------------
 %%% Start a new child.
 %%% ---------------------------------------------------
 
 handle_start_child(Child, State) ->
-    case get_child(Child#child.name, State) of
-	false ->
+    case find_child(Child#child.id, State) of
+	error ->
 	    case do_start_child(State#state.name, Child) of
-		{ok, undefined} when Child#child.restart_type =:= temporary ->
+		{ok, undefined} when ?is_temporary(Child) ->
 		    {{ok, undefined}, State};
 		{ok, Pid} ->
 		    {{ok, Pid}, save_child(Child#child{pid = Pid}, State)};
@@ -731,9 +663,9 @@ handle_start_child(Child, State) ->
 		{error, What} ->
 		    {{error, {What, Child}}, State}
 	    end;
-	{value, OldChild} when is_pid(OldChild#child.pid) ->
+	{ok, OldChild} when is_pid(OldChild#child.pid) ->
 	    {{error, {already_started, OldChild#child.pid}}, State};
-	{value, _OldChild} ->
+	{ok, _OldChild} ->
 	    {{error, already_present}, State}
     end.
 
@@ -742,63 +674,45 @@ handle_start_child(Child, State) ->
 %%% Returns: {ok, state()} | {shutdown, state()}
 %%% ---------------------------------------------------
 
-restart_child(Pid, Reason, #state{children = [Child]} = State) when ?is_simple(State) ->
-    RestartType = Child#child.restart_type,
-    case dynamic_child_args(Pid, RestartType, State#state.dynamics) of
-	{ok, Args} ->
-	    {M, F, _} = Child#child.mfargs,
-	    NChild = Child#child{pid = Pid, mfargs = {M, F, Args}},
-	    do_restart(RestartType, Reason, NChild, State);
-	error ->
-            {ok, State}
-    end;
-
 restart_child(Pid, Reason, State) ->
-    Children = State#state.children,
-    case lists:keyfind(Pid, #child.pid, Children) of
-	#child{restart_type = RestartType} = Child ->
-	    do_restart(RestartType, Reason, Child, State);
-	false ->
+    case find_child_and_args(Pid, State) of
+        {ok, Child} ->
+	    do_restart(Reason, Child, State);
+	error ->
 	    {ok, State}
     end.
 
-do_restart(permanent, Reason, Child, State) ->
+do_restart(Reason, Child, State) when ?is_permanent(Child) ->
     report_error(child_terminated, Reason, Child, State#state.name),
     restart(Child, State);
-do_restart(_, normal, Child, State) ->
-    NState = state_del_child(Child, State),
+do_restart(normal, Child, State) ->
+    NState = del_child(Child, State),
     {ok, NState};
-do_restart(_, shutdown, Child, State) ->
-    NState = state_del_child(Child, State),
+do_restart(shutdown, Child, State) ->
+    NState = del_child(Child, State),
     {ok, NState};
-do_restart(_, {shutdown, _Term}, Child, State) ->
-    NState = state_del_child(Child, State),
+do_restart({shutdown, _Term}, Child, State) ->
+    NState = del_child(Child, State),
     {ok, NState};
-do_restart(transient, Reason, Child, State) ->
+do_restart(Reason, Child, State) when ?is_transient(Child) ->
     report_error(child_terminated, Reason, Child, State#state.name),
     restart(Child, State);
-do_restart(temporary, Reason, Child, State) ->
+do_restart(Reason, Child, State) when ?is_temporary(Child) ->
     report_error(child_terminated, Reason, Child, State#state.name),
-    NState = state_del_child(Child, State),
+    NState = del_child(Child, State),
     {ok, NState}.
 
 restart(Child, State) ->
     case add_restart(State) of
 	{ok, NState} ->
 	    case restart(NState#state.strategy, Child, NState) of
-		{try_again,NState2} ->
+		{{try_again, TryAgainId}, NState2} ->
 		    %% Leaving control back to gen_server before
 		    %% trying again. This way other incoming requsts
 		    %% for the supervisor can be handled - e.g. a
 		    %% shutdown request for the supervisor or the
 		    %% child.
-		    Id = if ?is_simple(State) -> Child#child.pid;
-			    true -> Child#child.name
-			 end,
-		    ok = try_again_restart(self(), Id),
-		    {ok,NState2};
-		{try_again, NState2, #child{name=ChName}} ->
-		    ok = try_again_restart(self(), ChName),
+                    try_again_restart(TryAgainId),
 		    {ok,NState2};
 		Other ->
 		    Other
@@ -806,124 +720,111 @@ restart(Child, State) ->
 	{terminate, NState} ->
 	    report_error(shutdown, reached_max_restart_intensity,
 			 Child, State#state.name),
-	    {shutdown, remove_child(Child, NState)}
+	    {shutdown, del_child(Child, NState)}
     end.
 
 restart(simple_one_for_one, Child, State0) ->
     #child{pid = OldPid, mfargs = {M, F, A}} = Child,
-    State = case OldPid of
+    State1 = case OldPid of
 		?restarting(_) ->
 		    NRes = State0#state.dynamic_restarts - 1,
 		    State0#state{dynamic_restarts = NRes};
 		_ ->
 		    State0
 	    end,
-    Dynamics = ?DICTS:erase(OldPid, dynamics_db(Child#child.restart_type,
-					       State#state.dynamics)),
+    State2 = dyn_erase(OldPid, State1),
     case do_start_child_i(M, F, A) of
 	{ok, Pid} ->
-            DynamicsDb = {dict, ?DICTS:store(Pid, A, Dynamics)},
-	    NState = State#state{dynamics = DynamicsDb},
+            NState = dyn_store(Pid, A, State2),
 	    {ok, NState};
 	{ok, Pid, _Extra} ->
-            DynamicsDb = {dict, ?DICTS:store(Pid, A, Dynamics)},
-	    NState = State#state{dynamics = DynamicsDb},
+            NState = dyn_store(Pid, A, State2),
 	    {ok, NState};
 	{error, Error} ->
-	    NRestarts = State#state.dynamic_restarts + 1,
-            DynamicsDb = {dict, ?DICTS:store(restarting(OldPid), A, Dynamics)},
-	    NState = State#state{dynamic_restarts = NRestarts,
-				 dynamics = DynamicsDb},
-	    report_error(start_error, Error, Child, State#state.name),
-	    {try_again, NState}
+            ROldPid = restarting(OldPid),
+	    NRestarts = State2#state.dynamic_restarts + 1,
+	    State3 = State2#state{dynamic_restarts = NRestarts},
+            NState = dyn_store(ROldPid, A, State3),
+	    report_error(start_error, Error, Child, NState#state.name),
+	    {{try_again, ROldPid}, NState}
     end;
-restart(one_for_one, Child, State) ->
+restart(one_for_one, #child{id=Id} = Child, State) ->
     OldPid = Child#child.pid,
     case do_start_child(State#state.name, Child) of
 	{ok, Pid} ->
-	    NState = replace_child(Child#child{pid = Pid}, State),
+	    NState = set_pid(Pid, Id, State),
 	    {ok, NState};
 	{ok, Pid, _Extra} ->
-	    NState = replace_child(Child#child{pid = Pid}, State),
+	    NState = set_pid(Pid, Id, State),
 	    {ok, NState};
 	{error, Reason} ->
-	    NState = replace_child(Child#child{pid = restarting(OldPid)}, State),
+	    NState = set_pid(restarting(OldPid), Id, State),
 	    report_error(start_error, Reason, Child, State#state.name),
-	    {try_again, NState}
-    end;
-restart(rest_for_one, Child, State) ->
-    {ChAfter, ChBefore} = split_child(Child#child.pid, State#state.children),
-    ChAfter2 = terminate_children(ChAfter, State#state.name),
-    case start_children(ChAfter2, State#state.name) of
-	{ok, ChAfter3} ->
-	    {ok, State#state{children = ChAfter3 ++ ChBefore}};
-	{error, ChAfter3, {failed_to_start_child, ChName, _Reason}}
-	  when ChName =:= Child#child.name ->
-	    NChild = Child#child{pid=restarting(Child#child.pid)},
-	    NState = State#state{children = ChAfter3 ++ ChBefore},
-	    {try_again, replace_child(NChild,NState)};
-	{error, ChAfter3, {failed_to_start_child, ChName, _Reason}} ->
-	    NChild = lists:keyfind(ChName, #child.name, ChAfter3),
-	    NChild2 = NChild#child{pid=?restarting(undefined)},
-	    NState = State#state{children = ChAfter3 ++ ChBefore},
-	    {try_again, replace_child(NChild2,NState), NChild2}
+	    {{try_again,Id}, NState}
     end;
-restart(one_for_all, Child, State) ->
-    Children1 = del_child(Child#child.pid, State#state.children),
-    Children2 = terminate_children(Children1, State#state.name),
-    case start_children(Children2, State#state.name) of
-	{ok, NChs} ->
-	    {ok, State#state{children = NChs}};
-	{error, NChs, {failed_to_start_child, ChName, _Reason}}
-	  when ChName =:= Child#child.name ->
-	    NChild = Child#child{pid=restarting(Child#child.pid)},
-	    NState = State#state{children = NChs},
-	    {try_again, replace_child(NChild,NState)};
-	{error, NChs, {failed_to_start_child, ChName, _Reason}} ->
-	    NChild = lists:keyfind(ChName, #child.name, NChs),
-	    NChild2 = NChild#child{pid=?restarting(undefined)},
-	    NState = State#state{children = NChs},
-	    {try_again, replace_child(NChild2,NState), NChild2}
+restart(rest_for_one, #child{id=Id} = Child, #state{name=SupName} = State) ->
+    {ChAfter, ChBefore} = split_child(Id, State#state.children),
+    {Return, ChAfter2} = restart_multiple_children(Child, ChAfter, SupName),
+    {Return, State#state{children = append(ChAfter2,ChBefore)}};
+restart(one_for_all, Child, #state{name=SupName} = State) ->
+    Children1 = del_child(Child#child.id, State#state.children),
+    {Return, NChildren} = restart_multiple_children(Child, Children1, SupName),
+    {Return, State#state{children = NChildren}}.
+
+restart_multiple_children(Child, Children, SupName) ->
+    Children1 = terminate_children(Children, SupName),
+    case start_children(Children1, SupName) of
+	{ok, NChildren} ->
+	    {ok, NChildren};
+	{error, NChildren, {failed_to_start_child, FailedId, _Reason}} ->
+            NewPid = if FailedId =:= Child#child.id ->
+                             restarting(Child#child.pid);
+                        true ->
+                             ?restarting(undefined)
+                     end,
+	    {{try_again, FailedId}, set_pid(NewPid,FailedId,NChildren)}
     end.
 
 restarting(Pid) when is_pid(Pid) -> ?restarting(Pid);
 restarting(RPid) -> RPid.
 
+-spec try_again_restart(child_id() | {'restarting',pid()}) -> 'ok'.
+try_again_restart(TryAgainId) ->
+    gen_server:cast(self(), {try_again_restart, TryAgainId}).
+
 %%-----------------------------------------------------------------
 %% Func: terminate_children/2
-%% Args: Children = [child_rec()] in termination order
+%% Args: Children = children() % Ids in termination order
 %%       SupName = {local, atom()} | {global, atom()} | {pid(),Mod}
-%% Returns: NChildren = [child_rec()] in
-%%          startup order (reversed termination order)
+%% Returns: NChildren = children() % Ids in startup order
+%%                                 % (reversed termination order)
 %%-----------------------------------------------------------------
 terminate_children(Children, SupName) ->
-    terminate_children(Children, SupName, []).
-
-%% Temporary children should not be restarted and thus should
-%% be skipped when building the list of terminated children, although
-%% we do want them to be shut down as many functions from this module
-%% use this function to just clear everything.
-terminate_children([Child = #child{restart_type=temporary} | Children], SupName, Res) ->
-    _ = do_terminate(Child, SupName),
-    terminate_children(Children, SupName, Res);
-terminate_children([Child | Children], SupName, Res) ->
-    NChild = do_terminate(Child, SupName),
-    terminate_children(Children, SupName, [NChild | Res]);
-terminate_children([], _SupName, Res) ->
-    Res.
+    Terminate =
+        fun(_Id,Child) when ?is_temporary(Child) ->
+                %% Temporary children should not be restarted and thus should
+                %% be skipped when building the list of terminated children.
+                do_terminate(Child, SupName),
+                remove;
+           (_Id,Child) ->
+                do_terminate(Child, SupName),
+                {update,Child#child{pid=undefined}}
+        end,
+    {ok,NChildren} = children_map(Terminate, Children),
+    NChildren.
 
 do_terminate(Child, SupName) when is_pid(Child#child.pid) ->
     case shutdown(Child#child.pid, Child#child.shutdown) of
         ok ->
             ok;
-        {error, normal} when Child#child.restart_type =/= permanent ->
+        {error, normal} when not (?is_permanent(Child)) ->
             ok;
         {error, OtherReason} ->
             report_error(shutdown_error, OtherReason, Child, SupName)
     end,
-    Child#child{pid = undefined};
-do_terminate(Child, _SupName) ->
-    Child#child{pid = undefined}.
+    ok;
+do_terminate(_Child, _SupName) ->
+    ok.
 
 %%-----------------------------------------------------------------
 %% Shutdowns a child. We must check the EXIT value 
@@ -996,66 +897,50 @@ monitor_child(Pid) ->
 	    ok   
     end.
 
-
 %%-----------------------------------------------------------------
-%% Func: terminate_dynamic_children/3
-%% Args: Child    = child_rec()
-%%       Dynamics = ?DICT() | ?SET()
-%%       SupName  = {local, atom()} | {global, atom()} | {pid(),Mod}
+%% Func: terminate_dynamic_children/1
+%% Args: State
 %% Returns: ok
 %%
-%%
 %% Shutdown all dynamic children. This happens when the supervisor is
 %% stopped. Because the supervisor can have millions of dynamic children, we
-%% can have an significative overhead here.
+%% can have a significative overhead here.
 %%-----------------------------------------------------------------
-terminate_dynamic_children(Child, Dynamics, SupName) ->
-    {Pids, EStack0} = monitor_dynamic_children(Child, Dynamics),
-    Sz = ?SETS:size(Pids),
+terminate_dynamic_children(State) ->
+    Child = get_dynamic_child(State),
+    {Pids, EStack0} = monitor_dynamic_children(Child,State),
+    Sz = sets:size(Pids),
     EStack = case Child#child.shutdown of
                  brutal_kill ->
-                     ?SETS:fold(fun(P, _) -> exit(P, kill) end, ok, Pids),
+                     sets:fold(fun(P, _) -> exit(P, kill) end, ok, Pids),
                      wait_dynamic_children(Child, Pids, Sz, undefined, EStack0);
                  infinity ->
-                     ?SETS:fold(fun(P, _) -> exit(P, shutdown) end, ok, Pids),
+                     sets:fold(fun(P, _) -> exit(P, shutdown) end, ok, Pids),
                      wait_dynamic_children(Child, Pids, Sz, undefined, EStack0);
                  Time ->
-                     ?SETS:fold(fun(P, _) -> exit(P, shutdown) end, ok, Pids),
+                     sets:fold(fun(P, _) -> exit(P, shutdown) end, ok, Pids),
                      TRef = erlang:start_timer(Time, self(), kill),
                      wait_dynamic_children(Child, Pids, Sz, TRef, EStack0)
              end,
     %% Unroll stacked errors and report them
-    ?DICTS:fold(fun(Reason, Ls, _) ->
-                       report_error(shutdown_error, Reason,
-                                    Child#child{pid=Ls}, SupName)
-               end, ok, EStack).
-
-
-monitor_dynamic_children(#child{restart_type=temporary}, Dynamics) ->
-    ?SETS:fold(fun(P, {Pids, EStack}) ->
-                       case monitor_child(P) of
-                           ok ->
-                               {?SETS:add_element(P, Pids), EStack};
-                           {error, normal} ->
-                               {Pids, EStack};
-                           {error, Reason} ->
-                               {Pids, ?DICTS:append(Reason, P, EStack)}
-                       end
-               end, {?SETS:new(), ?DICTS:new()}, Dynamics);
-monitor_dynamic_children(#child{restart_type=RType}, Dynamics) ->
-    ?DICTS:fold(fun(P, _, {Pids, EStack}) when is_pid(P) ->
-                       case monitor_child(P) of
-                           ok ->
-                               {?SETS:add_element(P, Pids), EStack};
-                           {error, normal} when RType =/= permanent ->
-                               {Pids, EStack};
-                           {error, Reason} ->
-                               {Pids, ?DICTS:append(Reason, P, EStack)}
-                       end;
-		  (?restarting(_), _, {Pids, EStack}) ->
-		       {Pids, EStack}
-               end, {?SETS:new(), ?DICTS:new()}, Dynamics).
-
+    dict:fold(fun(Reason, Ls, _) ->
+                      report_error(shutdown_error, Reason,
+                                   Child#child{pid=Ls}, State#state.name)
+              end, ok, EStack).
+
+monitor_dynamic_children(Child,State) ->
+    dyn_fold(fun(P,{Pids, EStack}) when is_pid(P) ->
+                     case monitor_child(P) of
+                         ok ->
+                             {sets:add_element(P, Pids), EStack};
+                         {error, normal} when not (?is_permanent(Child)) ->
+                             {Pids, EStack};
+                         {error, Reason} ->
+                             {Pids, dict:append(Reason, P, EStack)}
+                     end;
+                (?restarting(_), {Pids, EStack}) ->
+                     {Pids, EStack}
+             end, {sets:new(), dict:new()}, State).
 
 wait_dynamic_children(_Child, _Pids, 0, undefined, EStack) ->
     EStack;
@@ -1073,39 +958,38 @@ wait_dynamic_children(#child{shutdown=brutal_kill} = Child, Pids, Sz,
                       TRef, EStack) ->
     receive
         {'DOWN', _MRef, process, Pid, killed} ->
-            wait_dynamic_children(Child, ?SETS:del_element(Pid, Pids), Sz-1,
+            wait_dynamic_children(Child, sets:del_element(Pid, Pids), Sz-1,
                                   TRef, EStack);
 
         {'DOWN', _MRef, process, Pid, Reason} ->
-            wait_dynamic_children(Child, ?SETS:del_element(Pid, Pids), Sz-1,
-                                  TRef, ?DICTS:append(Reason, Pid, EStack))
+            wait_dynamic_children(Child, sets:del_element(Pid, Pids), Sz-1,
+                                  TRef, dict:append(Reason, Pid, EStack))
     end;
-wait_dynamic_children(#child{restart_type=RType} = Child, Pids, Sz,
-                      TRef, EStack) ->
+wait_dynamic_children(Child, Pids, Sz, TRef, EStack) ->
     receive
         {'DOWN', _MRef, process, Pid, shutdown} ->
-            wait_dynamic_children(Child, ?SETS:del_element(Pid, Pids), Sz-1,
+            wait_dynamic_children(Child, sets:del_element(Pid, Pids), Sz-1,
                                   TRef, EStack);
 
         {'DOWN', _MRef, process, Pid, {shutdown, _}} ->
-            wait_dynamic_children(Child, ?SETS:del_element(Pid, Pids), Sz-1,
+            wait_dynamic_children(Child, sets:del_element(Pid, Pids), Sz-1,
                                   TRef, EStack);
 
-        {'DOWN', _MRef, process, Pid, normal} when RType =/= permanent ->
-            wait_dynamic_children(Child, ?SETS:del_element(Pid, Pids), Sz-1,
+        {'DOWN', _MRef, process, Pid, normal} when not (?is_permanent(Child)) ->
+            wait_dynamic_children(Child, sets:del_element(Pid, Pids), Sz-1,
                                   TRef, EStack);
 
         {'DOWN', _MRef, process, Pid, Reason} ->
-            wait_dynamic_children(Child, ?SETS:del_element(Pid, Pids), Sz-1,
-                                  TRef, ?DICTS:append(Reason, Pid, EStack));
+            wait_dynamic_children(Child, sets:del_element(Pid, Pids), Sz-1,
+                                  TRef, dict:append(Reason, Pid, EStack));
 
         {timeout, TRef, kill} ->
-            ?SETS:fold(fun(P, _) -> exit(P, kill) end, ok, Pids),
+            sets:fold(fun(P, _) -> exit(P, kill) end, ok, Pids),
             wait_dynamic_children(Child, Pids, Sz, undefined, EStack)
     end.
 
 %%-----------------------------------------------------------------
-%% Child/State manipulating functions.
+%% Access #state.children
 %%-----------------------------------------------------------------
 
 %% Note we do not want to save the parameter list for temporary processes as
@@ -1113,114 +997,184 @@ wait_dynamic_children(#child{restart_type=RType} = Child, Pids, Sz,
 %% Especially for dynamic children to simple_one_for_one supervisors
 %% it could become very costly as it is not uncommon to spawn
 %% very many such processes.
-save_child(#child{restart_type = temporary,
-		  mfargs = {M, F, _}} = Child, #state{children = Children} = State) ->
-    State#state{children = [Child#child{mfargs = {M, F, undefined}} |Children]};
-save_child(Child, #state{children = Children} = State) ->
-    State#state{children = [Child |Children]}.
-
-save_dynamic_child(temporary, Pid, _, #state{dynamics = Dynamics} = State) ->
-    DynamicsDb = dynamics_db(temporary, Dynamics),
-    State#state{dynamics = {set, ?SETS:add_element(Pid, DynamicsDb)}};
-save_dynamic_child(RestartType, Pid, Args, #state{dynamics = Dynamics} = State) ->
-    DynamicsDb = dynamics_db(RestartType, Dynamics),
-    State#state{dynamics = {dict, ?DICTS:store(Pid, Args, DynamicsDb)}}.
-
-dynamics_db(temporary, undefined) ->
-    ?SETS:new();
-dynamics_db(_, undefined) ->
-    ?DICTS:new();
-dynamics_db(_, {_Tag, DynamicsDb}) ->
-    DynamicsDb.
-
-dynamic_child_args(_Pid, temporary, _DynamicsDb) ->
-    {ok, undefined};
-dynamic_child_args(Pid, _RT, {dict, DynamicsDb}) ->
-    ?DICTS:find(Pid, DynamicsDb);
-dynamic_child_args(_Pid, _RT, undefined) ->
-    error.
-
-state_del_child(#child{pid = Pid, restart_type = temporary}, State) when ?is_simple(State) ->
-    NDynamics = ?SETS:del_element(Pid, dynamics_db(temporary, State#state.dynamics)),
-    State#state{dynamics = {set, NDynamics}};
-state_del_child(#child{pid = Pid, restart_type = RType}, State) when ?is_simple(State) ->
-    NDynamics = ?DICTS:erase(Pid, dynamics_db(RType, State#state.dynamics)),
-    State#state{dynamics = {dict, NDynamics}};
-state_del_child(Child, State) ->
-    NChildren = del_child(Child#child.name, State#state.children),
-    State#state{children = NChildren}.
-
-del_child(Name, [Ch|Chs]) when Ch#child.name =:= Name, Ch#child.restart_type =:= temporary ->
-    Chs;
-del_child(Name, [Ch|Chs]) when Ch#child.name =:= Name ->
-    [Ch#child{pid = undefined} | Chs];
-del_child(Pid, [Ch|Chs]) when Ch#child.pid =:= Pid, Ch#child.restart_type =:= temporary ->
-    Chs;
-del_child(Pid, [Ch|Chs]) when Ch#child.pid =:= Pid ->
-    [Ch#child{pid = undefined} | Chs];
-del_child(Name, [Ch|Chs]) ->
-    [Ch|del_child(Name, Chs)];
-del_child(_, []) ->
-    [].
+-spec save_child(child_rec(), state()) -> state().
+save_child(#child{mfargs = {M, F, _}} = Child, State) when ?is_temporary(Child) ->
+    do_save_child(Child#child{mfargs = {M, F, undefined}}, State);
+save_child(Child, State) ->
+    do_save_child(Child, State).
+
+-spec do_save_child(child_rec(), state()) -> state().
+do_save_child(#child{id = Id} = Child, #state{children = {Ids,Db}} = State) ->
+    State#state{children = {[Id|Ids],Db#{Id => Child}}}.
+
+-spec del_child(child_rec(), state()) -> state();
+               (child_id(), children()) -> children().
+del_child(#child{pid = Pid}, State) when ?is_simple(State) ->
+    dyn_erase(Pid,State);
+del_child(Child, State) when is_record(Child,child), is_record(State,state) ->
+    NChildren = del_child(Child#child.id, State#state.children),
+    State#state{children = NChildren};
+del_child(Id, {Ids,Db}) ->
+    case maps:get(Id, Db) of
+        Child when Child#child.restart_type =:= temporary ->
+            {lists:delete(Id, Ids), maps:remove(Id, Db)};
+        Child ->
+            {Ids, Db#{Id=>Child#child{pid=undefined}}}
+    end.
 
-%% Chs = [S4, S3, Ch, S1, S0]
-%% Ret: {[S4, S3, Ch], [S1, S0]}
-split_child(Name, Chs) ->
-    split_child(Name, Chs, []).
-
-split_child(Name, [Ch|Chs], After) when Ch#child.name =:= Name ->
-    {lists:reverse([Ch#child{pid = undefined} | After]), Chs};
-split_child(Pid, [Ch|Chs], After) when Ch#child.pid =:= Pid ->
-    {lists:reverse([Ch#child{pid = undefined} | After]), Chs};
-split_child(Name, [Ch|Chs], After) ->
-    split_child(Name, Chs, [Ch | After]);
-split_child(_, [], After) ->
-    {lists:reverse(After), []}.
-
-get_child(Name, State) ->
-    get_child(Name, State, false).
-
-get_child(Pid, State, AllowPid) when AllowPid, is_pid(Pid) ->
-    get_dynamic_child(Pid, State);
-get_child(Name, State, _) ->
-    lists:keysearch(Name, #child.name, State#state.children).
-
-get_dynamic_child(Pid, #state{children=[Child], dynamics=Dynamics}) ->
-    case is_dynamic_pid(Pid, Dynamics) of
-	true ->
-	    {value, Child#child{pid=Pid}};
-	false ->
-	    RPid = restarting(Pid),
-	    case is_dynamic_pid(RPid, Dynamics) of
-		true ->
-		    {value, Child#child{pid=RPid}};
-		false ->
+%% In: {[S4, S3, Ch, S1, S0],Db}
+%% Ret: {{[S4, S3, Ch],Db1}, {[S1, S0],Db2}}
+%% Db1 and Db2 contain the keys in the lists they are associated with.
+-spec split_child(child_id(), children()) -> {children(), children()}.
+split_child(Id, {Ids,Db}) ->
+    {IdsAfter,IdsBefore} = split_ids(Id, Ids, []),
+    DbBefore = maps:with(IdsBefore,Db),
+    #{Id:=Ch} = DbAfter = maps:with(IdsAfter,Db),
+    {{IdsAfter,DbAfter#{Id=>Ch#child{pid=undefined}}},{IdsBefore,DbBefore}}.
+
+split_ids(Id, [Id|Ids], After) ->
+    {lists:reverse([Id|After]), Ids};
+split_ids(Id, [Other|Ids], After) ->
+    split_ids(Id, Ids, [Other | After]).
+
+%% Find the child record for a given Pid (dynamic child) or Id
+%% (non-dynamic child). This is called from the API functions.
+-spec find_child(pid() | child_id(), state()) -> {ok,child_rec()} | error.
+find_child(Pid, State) when is_pid(Pid), ?is_simple(State) ->
+    case find_dynamic_child(Pid, State) of
+        error ->
+            case find_dynamic_child(restarting(Pid), State) of
+                error ->
 		    case erlang:is_process_alive(Pid) of
-			true -> false;
-			false -> {value, Child}
-		    end
-	    end
+			true -> error;
+			false -> {ok, get_dynamic_child(State)}
+		    end;
+                Other ->
+                    Other
+            end;
+        Other ->
+            Other
+    end;
+find_child(Id, #state{children = {_Ids,Db}}) ->
+    maps:find(Id, Db).
+
+%% Get the child record - either by child id or by pid.  If
+%% simple_one_for_one, then insert the pid and args into the returned
+%% child record. This is called when trying to restart the child.
+-spec find_child_and_args(IdOrPid, state()) -> {ok, child_rec()} | error when
+      IdOrPid :: pid() | {restarting,pid()} | child_id().
+find_child_and_args(Pid, State) when ?is_simple(State) ->
+    case find_dynamic_child(Pid, State) of
+        {ok,#child{mfargs={M,F,_}} = Child} ->
+            {ok, Args} = dyn_args(Pid, State),
+            {ok, Child#child{mfargs = {M, F, Args}}};
+        error ->
+            error
+    end;
+find_child_and_args(Pid, State) when is_pid(Pid) ->
+    find_child_by_pid(Pid, State);
+find_child_and_args(Id, #state{children={_Ids,Db}})  ->
+    maps:find(Id, Db).
+
+%% Given the pid, find the child record for a dynamic child, and
+%% include the pid in the returned record.
+-spec find_dynamic_child(IdOrPid, state()) -> {ok, child_rec()} | error when
+      IdOrPid :: pid() | {restarting,pid()} | child_id().
+find_dynamic_child(Pid, State) ->
+    case dyn_exists(Pid, State) of
+        true ->
+            Child = get_dynamic_child(State),
+            {ok, Child#child{pid=Pid}};
+        false ->
+            error
     end.
 
-is_dynamic_pid(Pid, {dict, Dynamics}) ->
-    ?DICTS:is_key(Pid, Dynamics);
-is_dynamic_pid(Pid, {set, Dynamics}) ->
-    ?SETS:is_element(Pid, Dynamics);
-is_dynamic_pid(_Pid, undefined) ->
-    false.
-
-replace_child(Child, State) ->
-    Chs = do_replace_child(Child, State#state.children),
-    State#state{children = Chs}.
-
-do_replace_child(Child, [Ch|Chs]) when Ch#child.name =:= Child#child.name ->
-    [Child | Chs];
-do_replace_child(Child, [Ch|Chs]) ->
-    [Ch|do_replace_child(Child, Chs)].
+%% Given the pid, find the child record for a non-dyanamic child.
+-spec find_child_by_pid(IdOrPid, state()) -> {ok,child_rec()} | error when
+      IdOrPid :: pid() | {restarting,pid()}.
+find_child_by_pid(Pid,#state{children={_Ids,Db}}) ->
+    Fun = fun(_Id,#child{pid=P}=Ch,_) when P =:= Pid ->
+                  throw(Ch);
+             (_,_,error) ->
+                  error
+          end,
+    try maps:fold(Fun,error,Db)
+    catch throw:Child -> {ok,Child}
+    end.
 
-remove_child(Child, State) ->
-    Chs = lists:keydelete(Child#child.name, #child.name, State#state.children),
-    State#state{children = Chs}.
+%% Get the child record from a simple_one_for_one supervisor - no pid
+%% It is assumed that the child can always be found
+-spec get_dynamic_child(state()) -> child_rec().
+get_dynamic_child(#state{children={[Id],Db}}) ->
+    #{Id := Child} = Db,
+    Child.
+
+%% Update pid in the given child record and store it in the process state
+-spec set_pid(term(), child_id(), state()) -> state();
+             (term(), child_id(), children()) -> children().
+set_pid(Pid, Id, #state{children=Children} = State) ->
+    State#state{children = set_pid(Pid, Id, Children)};
+set_pid(Pid, Id, {Ids, Db}) ->
+    NewDb = maps:update_with(Id, fun(Child) -> Child#child{pid=Pid} end, Db),
+    {Ids,NewDb}.
+
+%% Remove the Id and the child record from the process state
+-spec remove_child(child_id(), state()) -> state().
+remove_child(Id, #state{children={Ids,Db}} = State) ->
+    NewIds = lists:delete(Id,Ids),
+    NewDb = maps:remove(Id,Db),
+    State#state{children = {NewIds,NewDb}}.
+
+%% In the order of Ids, traverse the children and update each child
+%% according to the return value of the Fun.
+%% On error, abort and return the merge of the old and the updated map.
+%% NOTE: The returned list of Ids is reverted compared to the input.
+-spec children_map(Fun, children()) -> {ok, children()} |
+                                       {error,children(),Reason} when
+      Fun :: fun((child_id(),child_rec()) -> {update,child_rec()} |
+                                             remove |
+                                             {abort, Reason}),
+      Reason :: term().
+children_map(Fun,{Ids,Db}) ->
+    children_map(Fun, Ids, Db, []).
+
+children_map(Fun,[Id|Ids],Db,Acc) ->
+    case Fun(Id,maps:get(Id,Db)) of
+        {update,Child} ->
+            children_map(Fun,Ids,Db#{Id => Child},[Id|Acc]);
+        remove ->
+            children_map(Fun,Ids,maps:remove(Id,Db),Acc);
+        {abort,Reason} ->
+            {error,{lists:reverse(Ids)++[Id|Acc],Db},Reason}
+    end;
+children_map(_Fun,[],Db,Acc) ->
+    {ok,{Acc,Db}}.
+
+%% In the order of Ids, map over all children and return the list
+-spec children_to_list(Fun, children()) -> List when
+      Fun :: fun((child_id(), child_rec()) -> Elem),
+      List :: list(Elem),
+      Elem :: term().
+children_to_list(Fun,{Ids,Db}) ->
+    children_to_list(Fun, Ids, Db, []).
+children_to_list(Fun,[Id|Ids],Db,Acc) ->
+    children_to_list(Fun,Ids,Db,[Fun(Id,maps:get(Id,Db))|Acc]);
+children_to_list(_Fun,[],_Db,Acc) ->
+    lists:reverse(Acc).
+
+%% The order is not important - so ignore Ids
+-spec children_fold(Fun, Acc0, children()) -> Acc1 when
+      Fun :: fun((child_id(), child_rec(), AccIn) -> AccOut),
+      Acc0 :: term(),
+      Acc1 :: term(),
+      AccIn :: term(),
+      AccOut :: term().
+children_fold(Fun,Init,{_Ids,Db}) ->
+    maps:fold(Fun, Init, Db).
+
+-spec append(children(), children()) -> children().
+append({Ids1,Db1},{Ids2,Db2}) ->
+    {Ids1++Ids2,maps:merge(Db1,Db2)}.
 
 %%-----------------------------------------------------------------
 %% Func: init_state/4
@@ -1290,27 +1244,27 @@ supname(N, _)      -> N.
 %%% Returns: {ok, [child_rec()]} | Error
 %%% ------------------------------------------------------
 
-check_startspec(Children) -> check_startspec(Children, []).
+check_startspec(Children) -> check_startspec(Children, [], #{}).
 
-check_startspec([ChildSpec|T], Res) ->
+check_startspec([ChildSpec|T], Ids, Db) ->
     case check_childspec(ChildSpec) of
-	{ok, Child} ->
-	    case lists:keymember(Child#child.name, #child.name, Res) of
+	{ok, #child{id=Id}=Child} ->
+	    case maps:is_key(Id, Db) of
 		%% The error message duplicate_child_name is kept for
 		%% backwards compatibility, although
 		%% duplicate_child_id would be more correct.
-		true -> {duplicate_child_name, Child#child.name};
-		false -> check_startspec(T, [Child | Res])
+		true -> {duplicate_child_name, Id};
+		false -> check_startspec(T, [Id | Ids], Db#{Id=>Child})
 	    end;
 	Error -> Error
     end;
-check_startspec([], Res) ->
-    {ok, lists:reverse(Res)}.
+check_startspec([], Ids, Db) ->
+    {ok, {lists:reverse(Ids),Db}}.
 
 check_childspec(ChildSpec) when is_map(ChildSpec) ->
     catch do_check_childspec(maps:merge(?default_child_spec,ChildSpec));
-check_childspec({Name, Func, RestartType, Shutdown, ChildType, Mods}) ->
-    check_childspec(#{id => Name,
+check_childspec({Id, Func, RestartType, Shutdown, ChildType, Mods}) ->
+    check_childspec(#{id => Id,
 		      start => Func,
 		      restart => RestartType,
 		      shutdown => Shutdown,
@@ -1320,15 +1274,15 @@ check_childspec(X) -> {invalid_child_spec, X}.
 
 do_check_childspec(#{restart := RestartType,
 		     type := ChildType} = ChildSpec)->
-    Name = case ChildSpec of
-	       #{id := N} -> N;
+    Id = case ChildSpec of
+	       #{id := I} -> I;
 	       _ -> throw(missing_id)
 	   end,
     Func = case ChildSpec of
 	       #{start := F} -> F;
 	       _ -> throw(missing_start)
 	   end,
-    validName(Name),
+    validId(Id),
     validFunc(Func),
     validRestartType(RestartType),
     validChildType(ChildType),
@@ -1343,14 +1297,14 @@ do_check_childspec(#{restart := RestartType,
 	       _ -> {M,_,_} = Func, [M]
 	   end,
     validMods(Mods),
-    {ok, #child{name = Name, mfargs = Func, restart_type = RestartType,
+    {ok, #child{id = Id, mfargs = Func, restart_type = RestartType,
 		shutdown = Shutdown, child_type = ChildType, modules = Mods}}.
 
 validChildType(supervisor) -> true;
 validChildType(worker) -> true;
 validChildType(What) -> throw({invalid_child_type, What}).
 
-validName(_Name) -> true.
+validId(_Id) -> true.
 
 validFunc({M, F, A}) when is_atom(M), 
                           is_atom(F), 
@@ -1379,13 +1333,13 @@ validMods(Mods) when is_list(Mods) ->
 		  Mods);
 validMods(Mods) -> throw({invalid_modules, Mods}).
 
-child_to_spec(#child{name = Name,
+child_to_spec(#child{id = Id,
 		    mfargs = Func,
 		    restart_type = RestartType,
 		    shutdown = Shutdown,
 		    child_type = ChildType,
 		    modules = Mods}) ->
-    #{id => Name,
+    #{id => Id,
       start => Func,
       restart => RestartType,
       shutdown => Shutdown,
@@ -1439,17 +1393,16 @@ report_error(Error, Reason, Child, SupName) ->
 		{offender, extract_child(Child)}],
     error_logger:error_report(supervisor_report, ErrorMsg).
 
-
 extract_child(Child) when is_list(Child#child.pid) ->
     [{nb_children, length(Child#child.pid)},
-     {id, Child#child.name},
+     {id, Child#child.id},
      {mfargs, Child#child.mfargs},
      {restart_type, Child#child.restart_type},
      {shutdown, Child#child.shutdown},
      {child_type, Child#child.child_type}];
 extract_child(Child) ->
     [{pid, Child#child.pid},
-     {id, Child#child.name},
+     {id, Child#child.id},
      {mfargs, Child#child.mfargs},
      {restart_type, Child#child.restart_type},
      {shutdown, Child#child.shutdown},
@@ -1465,3 +1418,46 @@ format_status(terminate, [_PDict, State]) ->
 format_status(_, [_PDict, State]) ->
     [{data, [{"State", State}]},
      {supervisor, [{"Callback", State#state.module}]}].
+
+%%%-----------------------------------------------------------------
+%%% Dynamics database access
+dyn_size(#state{dynamics = {Mod,Db}}) ->
+    Mod:size(Db).
+
+dyn_erase(Pid,#state{dynamics={sets,Db}}=State) ->
+    State#state{dynamics={sets,sets:del_element(Pid,Db)}};
+dyn_erase(Pid,#state{dynamics={maps,Db}}=State) ->
+    State#state{dynamics={maps,maps:remove(Pid,Db)}}.
+
+dyn_store(Pid,_,#state{dynamics={sets,Db}}=State) ->
+    State#state{dynamics={sets,sets:add_element(Pid,Db)}};
+dyn_store(Pid,Args,#state{dynamics={maps,Db}}=State) ->
+    State#state{dynamics={maps,Db#{Pid => Args}}}.
+
+dyn_fold(Fun,Init,#state{dynamics={sets,Db}}) ->
+    sets:fold(Fun,Init,Db);
+dyn_fold(Fun,Init,#state{dynamics={maps,Db}}) ->
+    maps:fold(fun(Pid,_,Acc) -> Fun(Pid,Acc) end, Init, Db).
+
+dyn_map(Fun, #state{dynamics={sets,Db}}) ->
+    lists:map(Fun, sets:to_list(Db));
+dyn_map(Fun, #state{dynamics={maps,Db}}) ->
+    lists:map(Fun, maps:keys(Db)).
+
+dyn_exists(Pid, #state{dynamics={sets, Db}}) ->
+    sets:is_element(Pid, Db);
+dyn_exists(Pid, #state{dynamics={maps, Db}}) ->
+    maps:is_key(Pid, Db).
+
+dyn_args(_Pid, #state{dynamics={sets, _Db}}) ->
+    {ok,undefined};
+dyn_args(Pid, #state{dynamics={maps, Db}}) ->
+    maps:find(Pid, Db).
+
+dyn_init(State) ->
+    dyn_init(get_dynamic_child(State),State).
+
+dyn_init(Child,State) when ?is_temporary(Child) ->
+    State#state{dynamics={sets,sets:new()}};
+dyn_init(_Child,State) ->
+    State#state{dynamics={maps,maps:new()}}.
diff --git a/lib/stdlib/src/uri_string.erl b/lib/stdlib/src/uri_string.erl
new file mode 100644
index 0000000000..a84679c595
--- /dev/null
+++ b/lib/stdlib/src/uri_string.erl
@@ -0,0 +1,2069 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+%%
+%% [RFC 3986, Chapter 2.2. Reserved Characters]
+%%
+%%   reserved    = gen-delims / sub-delims
+%%
+%%   gen-delims  = ":" / "/" / "?" / "#" / "[" / "]" / "@"
+%%
+%%   sub-delims  = "!" / "$" / "&" / "'" / "(" / ")"
+%%               / "*" / "+" / "," / ";" / "="
+%%
+%%
+%% [RFC 3986, Chapter 2.3. Unreserved Characters]
+%%
+%%   unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"
+%%
+%%
+%% [RFC 3986, Chapter 3. Syntax Components]
+%%
+%% The generic URI syntax consists of a hierarchical sequence of
+%% components referred to as the scheme, authority, path, query, and
+%% fragment.
+%%
+%%    URI         = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
+%%
+%%    hier-part   = "//" authority path-abempty
+%%                   / path-absolute
+%%                   / path-rootless
+%%                   / path-empty
+%%
+%%    The scheme and path components are required, though the path may be
+%%    empty (no characters).  When authority is present, the path must
+%%    either be empty or begin with a slash ("/") character.  When
+%%    authority is not present, the path cannot begin with two slash
+%%    characters ("//").  These restrictions result in five different ABNF
+%%    rules for a path (Section 3.3), only one of which will match any
+%%    given URI reference.
+%%
+%%    The following are two example URIs and their component parts:
+%%
+%%          foo://example.com:8042/over/there?name=ferret#nose
+%%          \_/   \______________/\_________/ \_________/ \__/
+%%           |           |            |            |        |
+%%        scheme     authority       path        query   fragment
+%%           |   _____________________|__
+%%          / \ /                        \
+%%          urn:example:animal:ferret:nose
+%%
+%%
+%% [RFC 3986, Chapter 3.1. Scheme]
+%%
+%% Each URI begins with a scheme name that refers to a specification for
+%% assigning identifiers within that scheme.
+%%
+%%    scheme      = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
+%%
+%%
+%% [RFC 3986, Chapter 3.2. Authority]
+%%
+%% Many URI schemes include a hierarchical element for a naming
+%% authority so that governance of the name space defined by the
+%% remainder of the URI is delegated to that authority (which may, in
+%% turn, delegate it further).
+%%
+%%    authority   = [ userinfo "@" ] host [ ":" port ]
+%%
+%%
+%% [RFC 3986, Chapter 3.2.1. User Information]
+%%
+%% The userinfo subcomponent may consist of a user name and, optionally,
+%% scheme-specific information about how to gain authorization to access
+%% the resource. The user information, if present, is followed by a
+%% commercial at-sign ("@") that delimits it from the host.
+%%
+%%    userinfo    = *( unreserved / pct-encoded / sub-delims / ":" )
+%%
+%%
+%% [RFC 3986, Chapter 3.2.2. Host]
+%%
+%% The host subcomponent of authority is identified by an IP literal
+%% encapsulated within square brackets, an IPv4 address in dotted-
+%% decimal form, or a registered name.
+%%
+%%    host        = IP-literal / IPv4address / reg-name
+%%
+%%    IP-literal = "[" ( IPv6address / IPvFuture  ) "]"
+%%
+%%    IPvFuture  = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )
+%%
+%%    IPv6address =                            6( h16 ":" ) ls32
+%%                /                       "::" 5( h16 ":" ) ls32
+%%                / [               h16 ] "::" 4( h16 ":" ) ls32
+%%                / [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
+%%                / [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
+%%                / [ *3( h16 ":" ) h16 ] "::"    h16 ":"   ls32
+%%                / [ *4( h16 ":" ) h16 ] "::"              ls32
+%%                / [ *5( h16 ":" ) h16 ] "::"              h16
+%%                / [ *6( h16 ":" ) h16 ] "::"
+%%
+%%    ls32        = ( h16 ":" h16 ) / IPv4address
+%%                ; least-significant 32 bits of address
+%%
+%%    h16         = 1*4HEXDIG
+%%                ; 16 bits of address represented in hexadecimal
+%%
+%%    IPv4address = dec-octet "." dec-octet "." dec-octet "." dec-octet
+%%
+%%    dec-octet   = DIGIT                 ; 0-9
+%%                / %x31-39 DIGIT         ; 10-99
+%%                / "1" 2DIGIT            ; 100-199
+%%                / "2" %x30-34 DIGIT     ; 200-249
+%%                / "25" %x30-35          ; 250-255
+%%
+%%    reg-name    = *( unreserved / pct-encoded / sub-delims )
+%%
+%%
+%% [RFC 3986, Chapter 3.2.2. Port]
+%%
+%% The port subcomponent of authority is designated by an optional port
+%% number in decimal following the host and delimited from it by a
+%% single colon (":") character.
+%%
+%%    port        = *DIGIT
+%%
+%%
+%% [RFC 3986, Chapter 3.3. Path]
+%%
+%% The path component contains data, usually organized in hierarchical
+%% form, that, along with data in the non-hierarchical query component
+%% (Section 3.4), serves to identify a resource within the scope of the
+%% URI's scheme and naming authority (if any).  The path is terminated
+%% by the first question mark ("?") or number sign ("#") character, or
+%% by the end of the URI.
+%%
+%%    path          = path-abempty    ; begins with "/" or is empty
+%%                  / path-absolute   ; begins with "/" but not "//"
+%%                  / path-noscheme   ; begins with a non-colon segment
+%%                  / path-rootless   ; begins with a segment
+%%                  / path-empty      ; zero characters
+%%
+%%    path-abempty  = *( "/" segment )
+%%    path-absolute = "/" [ segment-nz *( "/" segment ) ]
+%%    path-noscheme = segment-nz-nc *( "/" segment )
+%%    path-rootless = segment-nz *( "/" segment )
+%%    path-empty    = 0<pchar>
+%%    segment       = *pchar
+%%    segment-nz    = 1*pchar
+%%    segment-nz-nc = 1*( unreserved / pct-encoded / sub-delims / "@" )
+%%                  ; non-zero-length segment without any colon ":"
+%%
+%%    pchar         = unreserved / pct-encoded / sub-delims / ":" / "@"
+%%
+%%
+%% [RFC 3986, Chapter 3.4. Query]
+%%
+%% The query component contains non-hierarchical data that, along with
+%% data in the path component (Section 3.3), serves to identify a
+%% resource within the scope of the URI's scheme and naming authority
+%% (if any).  The query component is indicated by the first question
+%% mark ("?") character and terminated by a number sign ("#") character
+%% or by the end of the URI.
+%%
+%%    query       = *( pchar / "/" / "?" )
+%%
+%%
+%% [RFC 3986, Chapter 3.5. Fragment]
+%%
+%% The fragment identifier component of a URI allows indirect
+%% identification of a secondary resource by reference to a primary
+%% resource and additional identifying information.
+%%
+%%    fragment    = *( pchar / "/" / "?" )
+%%
+%%
+%% [RFC 3986, Chapter 4.1. URI Reference]
+%%
+%% URI-reference is used to denote the most common usage of a resource
+%% identifier.
+%%
+%%    URI-reference = URI / relative-ref
+%%
+%%
+%% [RFC 3986, Chapter 4.2. Relative Reference]
+%%
+%% A relative reference takes advantage of the hierarchical syntax
+%% (Section 1.2.3) to express a URI reference relative to the name space
+%% of another hierarchical URI.
+%%
+%%    relative-ref  = relative-part [ "?" query ] [ "#" fragment ]
+%%
+%%    relative-part = "//" authority path-abempty
+%%                  / path-absolute
+%%                  / path-noscheme
+%%                  / path-empty
+%%
+%%
+%% [RFC 3986, Chapter 4.3. Absolute URI]
+%%
+%% Some protocol elements allow only the absolute form of a URI without
+%% a fragment identifier.  For example, defining a base URI for later
+%% use by relative references calls for an absolute-URI syntax rule that
+%% does not allow a fragment.
+%%
+%%    absolute-URI  = scheme ":" hier-part [ "?" query ]
+%%
+-module(uri_string).
+
+%%-------------------------------------------------------------------------
+%% External API
+%%-------------------------------------------------------------------------
+-export([compose_query/1, compose_query/2,
+         dissect_query/1, normalize/1, parse/1,
+         recompose/1, transcode/2]).
+-export_type([error/0, uri_map/0, uri_string/0]).
+
+
+%%-------------------------------------------------------------------------
+%% Internal API
+%%-------------------------------------------------------------------------
+-export([is_host/1, is_path/1]).  % suppress warnings
+
+
+%%-------------------------------------------------------------------------
+%% Macros
+%%-------------------------------------------------------------------------
+-define(CHAR(Char), <<Char/utf8>>).
+-define(STRING_EMPTY, <<>>).
+-define(STRING(MatchStr), <<MatchStr/binary>>).
+-define(STRING_REST(MatchStr, Rest), <<MatchStr/utf8, Rest/binary>>).
+
+-define(DEC2HEX(X),
+        if ((X) >= 0) andalso ((X) =< 9) -> (X) + $0;
+           ((X) >= 10) andalso ((X) =< 15) -> (X) + $A - 10
+        end).
+
+-define(HEX2DEC(X),
+        if ((X) >= $0) andalso ((X) =< $9) -> (X) - $0;
+           ((X) >= $A) andalso ((X) =< $F) -> (X) - $A + 10;
+           ((X) >= $a) andalso ((X) =< $f) -> (X) - $a + 10
+        end).
+
+
+%%%=========================================================================
+%%%  API
+%%%=========================================================================
+
+%%-------------------------------------------------------------------------
+%% URI compliant with RFC 3986
+%% ASCII %x21 - %x7A ("!" - "z") except
+%%   %x34    "    double quote
+%%   %x60    <    less than
+%%   %x62    >    greater than
+%%   %x92    \    backslash
+%%   %x94    ^    caret / circumflex
+%%   %x96    `    grave / accent
+%%-------------------------------------------------------------------------
+-type uri_string() :: iodata().
+-type error() :: {error, atom(), term()}.
+
+
+%%-------------------------------------------------------------------------
+%% RFC 3986, Chapter 3. Syntax Components
+%%-------------------------------------------------------------------------
+-type uri_map() ::
+  #{fragment => unicode:chardata(),
+    host => unicode:chardata(),
+    path => unicode:chardata(),
+    port => non_neg_integer() | undefined,
+    query => unicode:chardata(),
+    scheme => unicode:chardata(),
+    userinfo => unicode:chardata()} | #{}.
+
+
+%%-------------------------------------------------------------------------
+%% Normalize URIs
+%%-------------------------------------------------------------------------
+-spec normalize(URIString) -> NormalizedURI when
+      URIString :: uri_string(),
+      NormalizedURI :: uri_string().
+normalize(URIString) ->
+    %% Percent-encoding normalization and case normalization for
+    %% percent-encoded triplets are achieved by running parse and
+    %% recompose on the input URI string.
+    recompose(
+      normalize_path_segment(
+        normalize_scheme_based(
+          normalize_case(
+            parse(URIString))))).
+
+
+%%-------------------------------------------------------------------------
+%% Parse URIs
+%%-------------------------------------------------------------------------
+-spec parse(URIString) -> URIMap when
+      URIString :: uri_string(),
+      URIMap :: uri_map()
+              | error().
+parse(URIString) when is_binary(URIString) ->
+    try parse_uri_reference(URIString, #{})
+    catch
+        throw:{error, Atom, RestData} -> {error, Atom, RestData}
+    end;
+parse(URIString) when is_list(URIString) ->
+    try
+        Binary = unicode:characters_to_binary(URIString),
+        Map = parse_uri_reference(Binary, #{}),
+        convert_mapfields_to_list(Map)
+    catch
+        throw:{error, Atom, RestData} -> {error, Atom, RestData}
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% Recompose URIs
+%%-------------------------------------------------------------------------
+-spec recompose(URIMap) -> URIString when
+      URIMap :: uri_map(),
+      URIString :: uri_string()
+                 | error().
+recompose(Map) ->
+    case is_valid_map(Map) of
+        false ->
+            {error, invalid_map, Map};
+        true ->
+            try
+                T0 = update_scheme(Map, empty),
+                T1 = update_userinfo(Map, T0),
+                T2 = update_host(Map, T1),
+                T3 = update_port(Map, T2),
+                T4 = update_path(Map, T3),
+                T5 = update_query(Map, T4),
+                update_fragment(Map, T5)
+            catch
+                throw:{error, Atom, RestData} -> {error, Atom, RestData}
+            end
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% Transcode URIs
+%%-------------------------------------------------------------------------
+-spec transcode(URIString, Options) -> Result when
+      URIString :: uri_string(),
+      Options :: [{in_encoding, unicode:encoding()}|{out_encoding, unicode:encoding()}],
+      Result :: uri_string()
+              | error().
+transcode(URIString, Options) when is_binary(URIString) ->
+    try
+        InEnc = proplists:get_value(in_encoding, Options, utf8),
+        OutEnc = proplists:get_value(out_encoding, Options, utf8),
+        List = convert_to_list(URIString, InEnc),
+        Output = transcode(List, [], InEnc, OutEnc),
+        convert_to_binary(Output, utf8, OutEnc)
+    catch
+        throw:{error, Atom, RestData} -> {error, Atom, RestData}
+    end;
+transcode(URIString, Options) when is_list(URIString) ->
+    InEnc = proplists:get_value(in_encoding, Options, utf8),
+    OutEnc = proplists:get_value(out_encoding, Options, utf8),
+    Flattened = flatten_list(URIString, InEnc),
+    try transcode(Flattened, [], InEnc, OutEnc)
+    catch
+        throw:{error, Atom, RestData} -> {error, Atom, RestData}
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% Functions for working with the query part of a URI as a list
+%% of key/value pairs.
+%% HTML5 - 4.10.22.6 URL-encoded form data
+%%-------------------------------------------------------------------------
+
+%%-------------------------------------------------------------------------
+%% Compose urlencoded query string from a list of unescaped key/value pairs.
+%% (application/x-www-form-urlencoded encoding algorithm)
+%%-------------------------------------------------------------------------
+-spec compose_query(QueryList) -> QueryString when
+      QueryList :: [{uri_string(), uri_string()}],
+      QueryString :: uri_string()
+                   | error().
+compose_query(List) ->
+    compose_query(List, [{encoding, utf8}]).
+
+
+-spec compose_query(QueryList, Options) -> QueryString when
+      QueryList :: [{uri_string(), uri_string()}],
+      Options :: [{encoding, atom()}],
+      QueryString :: uri_string()
+                   | error().
+compose_query([],_Options) ->
+    [];
+compose_query(List, Options) ->
+    try compose_query(List, Options, false, <<>>)
+    catch
+      throw:{error, Atom, RestData} -> {error, Atom, RestData}
+    end.
+%%
+compose_query([{Key,Value}|Rest], Options, IsList, Acc) ->
+    Separator = get_separator(Rest),
+    K = form_urlencode(Key, Options),
+    V = form_urlencode(Value, Options),
+    IsListNew = IsList orelse is_list(Key) orelse is_list(Value),
+    compose_query(Rest, Options, IsListNew, <<Acc/binary,K/binary,"=",V/binary,Separator/binary>>);
+compose_query([], _Options, IsList, Acc) ->
+    case IsList of
+        true -> convert_to_list(Acc, utf8);
+        false -> Acc
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% Dissect a query string into a list of unescaped key/value pairs.
+%% (application/x-www-form-urlencoded decoding algorithm)
+%%-------------------------------------------------------------------------
+-spec dissect_query(QueryString) -> QueryList when
+      QueryString :: uri_string(),
+      QueryList :: [{uri_string(), uri_string()}]
+                 | error().
+dissect_query(<<>>) ->
+    [];
+dissect_query([]) ->
+    [];
+dissect_query(QueryString) when is_list(QueryString) ->
+    try
+        B = convert_to_binary(QueryString, utf8, utf8),
+        dissect_query_key(B, true, [], <<>>, <<>>)
+    catch
+        throw:{error, Atom, RestData} -> {error, Atom, RestData}
+    end;
+dissect_query(QueryString) ->
+    try dissect_query_key(QueryString, false, [], <<>>, <<>>)
+    catch
+        throw:{error, Atom, RestData} -> {error, Atom, RestData}
+    end.
+
+
+%%%========================================================================
+%%% Internal functions
+%%%========================================================================
+
+%%-------------------------------------------------------------------------
+%% Converts Map fields to lists
+%%-------------------------------------------------------------------------
+convert_mapfields_to_list(Map) ->
+    Fun = fun (_, V) when is_binary(V) -> unicode:characters_to_list(V);
+              (_, V) -> V end,
+    maps:map(Fun, Map).
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 4.1. URI Reference]
+%%
+%% URI-reference is used to denote the most common usage of a resource
+%% identifier.
+%%
+%%    URI-reference = URI / relative-ref
+%%-------------------------------------------------------------------------
+-spec parse_uri_reference(binary(), uri_map()) -> uri_map().
+parse_uri_reference(<<>>, _) -> #{path => <<>>};
+parse_uri_reference(URIString, URI) ->
+    try parse_scheme_start(URIString, URI)
+    catch
+        throw:{_,_,_} ->
+            parse_relative_part(URIString, URI)
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 4.2. Relative Reference]
+%%
+%% A relative reference takes advantage of the hierarchical syntax
+%% (Section 1.2.3) to express a URI reference relative to the name space
+%% of another hierarchical URI.
+%%
+%%    relative-ref  = relative-part [ "?" query ] [ "#" fragment ]
+%%
+%%    relative-part = "//" authority path-abempty
+%%                  / path-absolute
+%%                  / path-noscheme
+%%                  / path-empty
+%%-------------------------------------------------------------------------
+-spec parse_relative_part(binary(), uri_map()) -> uri_map().
+parse_relative_part(?STRING_REST("//", Rest), URI) ->
+    %% Parse userinfo - "//" is NOT part of authority
+    try parse_userinfo(Rest, URI) of
+        {T, URI1} ->
+            Userinfo = calculate_parsed_userinfo(Rest, T),
+            URI2 = maybe_add_path(URI1),
+            URI2#{userinfo => decode_userinfo(Userinfo)}
+    catch
+        throw:{_,_,_} ->
+            {T, URI1} = parse_host(Rest, URI),
+            Host = calculate_parsed_host_port(Rest, T),
+            URI2 = maybe_add_path(URI1),
+            URI2#{host => decode_host(remove_brackets(Host))}
+    end;
+parse_relative_part(?STRING_REST($/, Rest), URI) ->
+    {T, URI1} = parse_segment(Rest, URI),  % path-absolute
+    Path = calculate_parsed_part(Rest, T),
+    URI1#{path => decode_path(?STRING_REST($/, Path))};
+parse_relative_part(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    URI2 = maybe_add_path(URI1),
+    URI2#{query => decode_query(Query)};
+parse_relative_part(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    URI2 = maybe_add_path(URI1),
+    URI2#{fragment => decode_fragment(Fragment)};
+parse_relative_part(?STRING_REST(Char, Rest), URI) ->
+    case is_segment_nz_nc(Char) of
+        true ->
+            {T, URI1} = parse_segment_nz_nc(Rest, URI),  % path-noscheme
+            Path = calculate_parsed_part(Rest, T),
+            URI1#{path => decode_path(?STRING_REST(Char, Path))};
+        false -> throw({error,invalid_uri,[Char]})
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.3. Path]
+%%
+%% The path component contains data, usually organized in hierarchical
+%% form, that, along with data in the non-hierarchical query component
+%% (Section 3.4), serves to identify a resource within the scope of the
+%% URI's scheme and naming authority (if any).  The path is terminated
+%% by the first question mark ("?") or number sign ("#") character, or
+%% by the end of the URI.
+%%
+%%    path          = path-abempty    ; begins with "/" or is empty
+%%                  / path-absolute   ; begins with "/" but not "//"
+%%                  / path-noscheme   ; begins with a non-colon segment
+%%                  / path-rootless   ; begins with a segment
+%%                  / path-empty      ; zero characters
+%%
+%%    path-abempty  = *( "/" segment )
+%%    path-absolute = "/" [ segment-nz *( "/" segment ) ]
+%%    path-noscheme = segment-nz-nc *( "/" segment )
+%%    path-rootless = segment-nz *( "/" segment )
+%%    path-empty    = 0<pchar>
+%%    segment       = *pchar
+%%    segment-nz    = 1*pchar
+%%    segment-nz-nc = 1*( unreserved / pct-encoded / sub-delims / "@" )
+%%                  ; non-zero-length segment without any colon ":"
+%%
+%%    pchar         = unreserved / pct-encoded / sub-delims / ":" / "@"
+%%-------------------------------------------------------------------------
+
+%%-------------------------------------------------------------------------
+%%    path-abempty
+%%-------------------------------------------------------------------------
+-spec parse_segment(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_segment(?STRING_REST($/, Rest), URI) ->
+    parse_segment(Rest, URI);  % segment
+parse_segment(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_segment(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_segment(?STRING_REST(Char, Rest), URI) ->
+    case is_pchar(Char) of
+        true -> parse_segment(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_segment(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+
+%%-------------------------------------------------------------------------
+%%    path-noscheme
+%%-------------------------------------------------------------------------
+-spec parse_segment_nz_nc(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_segment_nz_nc(?STRING_REST($/, Rest), URI) ->
+    parse_segment(Rest, URI);  % segment
+parse_segment_nz_nc(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_segment_nz_nc(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_segment_nz_nc(?STRING_REST(Char, Rest), URI) ->
+    case is_segment_nz_nc(Char) of
+        true -> parse_segment_nz_nc(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_segment_nz_nc(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+
+%% Check if char is pchar.
+-spec is_pchar(char()) -> boolean().
+is_pchar($%) -> true;  % pct-encoded
+is_pchar($:) -> true;
+is_pchar($@) -> true;
+is_pchar(Char) -> is_unreserved(Char) orelse is_sub_delim(Char).
+
+%% Check if char is segment_nz_nc.
+-spec is_segment_nz_nc(char()) -> boolean().
+is_segment_nz_nc($%) -> true;  % pct-encoded
+is_segment_nz_nc($@) -> true;
+is_segment_nz_nc(Char) -> is_unreserved(Char) orelse is_sub_delim(Char).
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.1. Scheme]
+%%
+%% Each URI begins with a scheme name that refers to a specification for
+%% assigning identifiers within that scheme.
+%%
+%%    scheme      = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
+%%-------------------------------------------------------------------------
+-spec parse_scheme_start(binary(), uri_map()) -> uri_map().
+parse_scheme_start(?STRING_REST(Char, Rest), URI) ->
+    case is_alpha(Char) of
+        true  -> {T, URI1} = parse_scheme(Rest, URI),
+                 Scheme = calculate_parsed_scheme(Rest, T),
+                 URI2 = maybe_add_path(URI1),
+		 URI2#{scheme => ?STRING_REST(Char, Scheme)};
+        false -> throw({error,invalid_uri,[Char]})
+    end.
+
+%% Add path component if it missing after parsing the URI.
+%% According to the URI specification there is always a
+%% path component in every URI-reference and it can be
+%% empty.
+maybe_add_path(Map) ->
+    case maps:is_key(path, Map) of
+        false ->
+            Map#{path => <<>>};
+        _Else ->
+            Map
+    end.
+
+
+
+-spec parse_scheme(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_scheme(?STRING_REST($:, Rest), URI) ->
+    {_, URI1} = parse_hier(Rest, URI),
+    {Rest, URI1};
+parse_scheme(?STRING_REST(Char, Rest), URI) ->
+    case is_scheme(Char) of
+        true  -> parse_scheme(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_scheme(?STRING_EMPTY, _URI) ->
+    throw({error,invalid_uri,<<>>}).
+
+
+%% Check if char is allowed in scheme
+-spec is_scheme(char()) -> boolean().
+is_scheme($+) -> true;
+is_scheme($-) -> true;
+is_scheme($.) -> true;
+is_scheme(Char) -> is_alpha(Char) orelse is_digit(Char).
+
+
+%%-------------------------------------------------------------------------
+%%    hier-part   = "//" authority path-abempty
+%%                   / path-absolute
+%%                   / path-rootless
+%%                   / path-empty
+%%-------------------------------------------------------------------------
+-spec parse_hier(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_hier(?STRING_REST("//", Rest), URI) ->
+    % Parse userinfo - "//" is NOT part of authority
+    try parse_userinfo(Rest, URI) of
+        {T, URI1} ->
+            Userinfo = calculate_parsed_userinfo(Rest, T),
+	    {Rest, URI1#{userinfo => decode_userinfo(Userinfo)}}
+    catch
+        throw:{_,_,_} ->
+            {T, URI1} = parse_host(Rest, URI),
+            Host = calculate_parsed_host_port(Rest, T),
+	    {Rest, URI1#{host => decode_host(remove_brackets(Host))}}
+    end;
+parse_hier(?STRING_REST($/, Rest), URI) ->
+    {T, URI1} = parse_segment(Rest, URI),  % path-absolute
+    Path = calculate_parsed_part(Rest, T),
+    {Rest, URI1#{path => decode_path(?STRING_REST($/, Path))}};
+parse_hier(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_hier(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_hier(?STRING_REST(Char, Rest), URI) ->  % path-rootless
+    case is_pchar(Char) of
+        true ->  % segment_nz
+            {T, URI1} = parse_segment(Rest, URI),
+            Path = calculate_parsed_part(Rest, T),
+            {Rest, URI1#{path => decode_path(?STRING_REST(Char, Path))}};
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_hier(?STRING_EMPTY, URI) ->
+    {<<>>, URI}.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.2. Authority]
+%%
+%% Many URI schemes include a hierarchical element for a naming
+%% authority so that governance of the name space defined by the
+%% remainder of the URI is delegated to that authority (which may, in
+%% turn, delegate it further).
+%%
+%% The authority component is preceded by a double slash ("//") and is
+%% terminated by the next slash ("/"), question mark ("?"), or number
+%% sign ("#") character, or by the end of the URI.
+%%
+%%    authority   = [ userinfo "@" ] host [ ":" port ]
+%%
+%%
+%% [RFC 3986, Chapter 3.2.1. User Information]
+%%
+%% The userinfo subcomponent may consist of a user name and, optionally,
+%% scheme-specific information about how to gain authorization to access
+%% the resource. The user information, if present, is followed by a
+%% commercial at-sign ("@") that delimits it from the host.
+%%
+%%    userinfo    = *( unreserved / pct-encoded / sub-delims / ":" )
+%%-------------------------------------------------------------------------
+-spec parse_userinfo(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_userinfo(?CHAR($@), URI) ->
+    {?STRING_EMPTY, URI#{host => <<>>}};
+parse_userinfo(?STRING_REST($@, Rest), URI) ->
+    {T, URI1} = parse_host(Rest, URI),
+    Host = calculate_parsed_host_port(Rest, T),
+    {Rest, URI1#{host => decode_host(remove_brackets(Host))}};
+parse_userinfo(?STRING_REST(Char, Rest), URI) ->
+    case is_userinfo(Char) of
+        true -> parse_userinfo(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_userinfo(?STRING_EMPTY, _URI) ->
+    %% URI cannot end in userinfo state
+    throw({error,invalid_uri,<<>>}).
+
+
+%% Check if char is allowed in userinfo
+-spec is_userinfo(char()) -> boolean().
+is_userinfo($%) -> true;  % pct-encoded
+is_userinfo($:) -> true;
+is_userinfo(Char) -> is_unreserved(Char) orelse is_sub_delim(Char).
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.2.2. Host]
+%%
+%% The host subcomponent of authority is identified by an IP literal
+%% encapsulated within square brackets, an IPv4 address in dotted-
+%% decimal form, or a registered name.
+%%
+%%    host        = IP-literal / IPv4address / reg-name
+%%
+%%    IP-literal = "[" ( IPv6address / IPvFuture  ) "]"
+%%
+%%    IPvFuture  = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )
+%%
+%%    IPv6address =                            6( h16 ":" ) ls32
+%%                /                       "::" 5( h16 ":" ) ls32
+%%                / [               h16 ] "::" 4( h16 ":" ) ls32
+%%                / [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
+%%                / [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
+%%                / [ *3( h16 ":" ) h16 ] "::"    h16 ":"   ls32
+%%                / [ *4( h16 ":" ) h16 ] "::"              ls32
+%%                / [ *5( h16 ":" ) h16 ] "::"              h16
+%%                / [ *6( h16 ":" ) h16 ] "::"
+%%
+%%    ls32        = ( h16 ":" h16 ) / IPv4address
+%%                ; least-significant 32 bits of address
+%%
+%%    h16         = 1*4HEXDIG
+%%                ; 16 bits of address represented in hexadecimal
+%%
+%%    IPv4address = dec-octet "." dec-octet "." dec-octet "." dec-octet
+%%
+%%    dec-octet   = DIGIT                 ; 0-9
+%%                / %x31-39 DIGIT         ; 10-99
+%%                / "1" 2DIGIT            ; 100-199
+%%                / "2" %x30-34 DIGIT     ; 200-249
+%%                / "25" %x30-35          ; 250-255
+%%
+%%    reg-name    = *( unreserved / pct-encoded / sub-delims )
+%%-------------------------------------------------------------------------
+-spec parse_host(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_host(?STRING_REST($:, Rest), URI) ->
+    {T, URI1} = parse_port(Rest, URI),
+    H = calculate_parsed_host_port(Rest, T),
+    Port = get_port(H),
+    {Rest, URI1#{port => Port}};
+parse_host(?STRING_REST($/, Rest), URI) ->
+    {T, URI1} = parse_segment(Rest, URI),  % path-abempty
+    Path = calculate_parsed_part(Rest, T),
+    {Rest, URI1#{path => decode_path(?STRING_REST($/, Path))}};
+parse_host(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_host(?STRING_REST($[, Rest), URI) ->
+    parse_ipv6_bin(Rest, [], URI);
+parse_host(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_host(?STRING_REST(Char, Rest), URI) ->
+    case is_digit(Char) of
+        true -> parse_ipv4_bin(Rest, [Char], URI);
+        false -> parse_reg_name(?STRING_REST(Char, Rest), URI)
+    end;
+parse_host(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+
+-spec parse_reg_name(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_reg_name(?STRING_REST($:, Rest), URI) ->
+    {T, URI1} = parse_port(Rest, URI),
+    H = calculate_parsed_host_port(Rest, T),
+    Port = get_port(H),
+    {Rest, URI1#{port => Port}};
+parse_reg_name(?STRING_REST($/, Rest), URI) ->
+    {T, URI1} = parse_segment(Rest, URI),  % path-abempty
+    Path = calculate_parsed_part(Rest, T),
+    {Rest, URI1#{path => decode_path(?STRING_REST($/, Path))}};
+parse_reg_name(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_reg_name(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_reg_name(?STRING_REST(Char, Rest), URI) ->
+    case is_reg_name(Char) of
+        true -> parse_reg_name(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_reg_name(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+%% Check if char is allowed in reg-name
+-spec is_reg_name(char()) -> boolean().
+is_reg_name($%) -> true;
+is_reg_name(Char) -> is_unreserved(Char) orelse is_sub_delim(Char).
+
+
+-spec parse_ipv4_bin(binary(), list(), uri_map()) -> {binary(), uri_map()}.
+parse_ipv4_bin(?STRING_REST($:, Rest), Acc, URI) ->
+    _ = validate_ipv4_address(lists:reverse(Acc)),
+    {T, URI1} = parse_port(Rest, URI),
+    H = calculate_parsed_host_port(Rest, T),
+    Port = get_port(H),
+    {Rest, URI1#{port => Port}};
+parse_ipv4_bin(?STRING_REST($/, Rest), Acc, URI) ->
+    _ = validate_ipv4_address(lists:reverse(Acc)),
+    {T, URI1} = parse_segment(Rest, URI),  % path-abempty
+    Path = calculate_parsed_part(Rest, T),
+    {Rest, URI1#{path => decode_path(?STRING_REST($/, Path))}};
+parse_ipv4_bin(?STRING_REST($?, Rest), Acc, URI) ->
+    _ = validate_ipv4_address(lists:reverse(Acc)),
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_ipv4_bin(?STRING_REST($#, Rest), Acc, URI) ->
+    _ = validate_ipv4_address(lists:reverse(Acc)),
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_ipv4_bin(?STRING_REST(Char, Rest), Acc, URI) ->
+    case is_ipv4(Char) of
+        true -> parse_ipv4_bin(Rest, [Char|Acc], URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_ipv4_bin(?STRING_EMPTY, Acc, URI) ->
+    _ = validate_ipv4_address(lists:reverse(Acc)),
+    {?STRING_EMPTY, URI}.
+
+
+%% Check if char is allowed in IPv4 addresses
+-spec is_ipv4(char()) -> boolean().
+is_ipv4($.) -> true;
+is_ipv4(Char) -> is_digit(Char).
+
+-spec validate_ipv4_address(list()) -> list().
+validate_ipv4_address(Addr) ->
+    case inet:parse_ipv4strict_address(Addr) of
+        {ok, _} -> Addr;
+        {error, _} -> throw({error,invalid_uri,Addr})
+    end.
+
+
+-spec parse_ipv6_bin(binary(), list(), uri_map()) -> {binary(), uri_map()}.
+parse_ipv6_bin(?STRING_REST($], Rest), Acc, URI) ->
+    _ = validate_ipv6_address(lists:reverse(Acc)),
+    parse_ipv6_bin_end(Rest, URI);
+parse_ipv6_bin(?STRING_REST(Char, Rest), Acc, URI) ->
+    case is_ipv6(Char) of
+        true -> parse_ipv6_bin(Rest, [Char|Acc], URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_ipv6_bin(?STRING_EMPTY, _Acc, _URI) ->
+    throw({error,invalid_uri,<<>>}).
+
+%% Check if char is allowed in IPv6 addresses
+-spec is_ipv6(char()) -> boolean().
+is_ipv6($:) -> true;
+is_ipv6($.) -> true;
+is_ipv6(Char) -> is_hex_digit(Char).
+
+
+-spec parse_ipv6_bin_end(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_ipv6_bin_end(?STRING_REST($:, Rest), URI) ->
+    {T, URI1} = parse_port(Rest, URI),
+    H = calculate_parsed_host_port(Rest, T),
+    Port = get_port(H),
+    {Rest, URI1#{port => Port}};
+parse_ipv6_bin_end(?STRING_REST($/, Rest), URI) ->
+    {T, URI1} = parse_segment(Rest, URI),  % path-abempty
+    Path = calculate_parsed_part(Rest, T),
+    {Rest, URI1#{path => decode_path(?STRING_REST($/, Path))}};
+parse_ipv6_bin_end(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_ipv6_bin_end(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_ipv6_bin_end(?STRING_REST(Char, Rest), URI) ->
+    case is_ipv6(Char) of
+        true -> parse_ipv6_bin_end(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_ipv6_bin_end(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+-spec validate_ipv6_address(list()) -> list().
+validate_ipv6_address(Addr) ->
+    case inet:parse_ipv6strict_address(Addr) of
+        {ok, _} -> Addr;
+        {error, _} -> throw({error,invalid_uri,Addr})
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.2.2. Port]
+%%
+%% The port subcomponent of authority is designated by an optional port
+%% number in decimal following the host and delimited from it by a
+%% single colon (":") character.
+%%
+%%    port        = *DIGIT
+%%-------------------------------------------------------------------------
+-spec parse_port(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_port(?STRING_REST($/, Rest), URI) ->
+    {T, URI1} = parse_segment(Rest, URI),  % path-abempty
+    Path = calculate_parsed_part(Rest, T),
+    {Rest, URI1#{path => decode_path(?STRING_REST($/, Path))}};
+parse_port(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_port(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_port(?STRING_REST(Char, Rest), URI) ->
+    case is_digit(Char) of
+        true -> parse_port(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_port(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.4. Query]
+%%
+%% The query component contains non-hierarchical data that, along with
+%% data in the path component (Section 3.3), serves to identify a
+%% resource within the scope of the URI's scheme and naming authority
+%% (if any).  The query component is indicated by the first question
+%% mark ("?") character and terminated by a number sign ("#") character
+%% or by the end of the URI.
+%%
+%%    query       = *( pchar / "/" / "?" )
+%%-------------------------------------------------------------------------
+-spec parse_query(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_query(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_query(?STRING_REST(Char, Rest), URI) ->
+    case is_query(Char) of
+        true -> parse_query(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_query(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+
+%% Check if char is allowed in query
+-spec is_query(char()) -> boolean().
+is_query($/) -> true;
+is_query($?) -> true;
+is_query(Char) -> is_pchar(Char).
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.5. Fragment]
+%%
+%% The fragment identifier component of a URI allows indirect
+%% identification of a secondary resource by reference to a primary
+%% resource and additional identifying information.
+%%
+%%    fragment    = *( pchar / "/" / "?" )
+%%-------------------------------------------------------------------------
+-spec parse_fragment(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_fragment(?STRING_REST(Char, Rest), URI) ->
+    case is_fragment(Char) of
+        true -> parse_fragment(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_fragment(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+
+%% Check if char is allowed in fragment
+-spec is_fragment(char()) -> boolean().
+is_fragment($/) -> true;
+is_fragment($?) -> true;
+is_fragment(Char) -> is_pchar(Char).
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 2.2. Reserved Characters]
+%%
+%%   reserved    = gen-delims / sub-delims
+%%
+%%   gen-delims  = ":" / "/" / "?" / "#" / "[" / "]" / "@"
+%%
+%%   sub-delims  = "!" / "$" / "&" / "'" / "(" / ")"
+%%               / "*" / "+" / "," / ";" / "="
+%%
+%%-------------------------------------------------------------------------
+
+%% Check if char is sub-delim.
+-spec is_sub_delim(char()) -> boolean().
+is_sub_delim($!) -> true;
+is_sub_delim($$) -> true;
+is_sub_delim($&) -> true;
+is_sub_delim($') -> true;
+is_sub_delim($() -> true;
+is_sub_delim($)) -> true;
+
+is_sub_delim($*) -> true;
+is_sub_delim($+) -> true;
+is_sub_delim($,) -> true;
+is_sub_delim($;) -> true;
+is_sub_delim($=) -> true;
+is_sub_delim(_) -> false.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 2.3. Unreserved Characters]
+%%
+%%   unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"
+%%
+%%-------------------------------------------------------------------------
+-spec is_unreserved(char()) -> boolean().
+is_unreserved($-) -> true;
+is_unreserved($.) -> true;
+is_unreserved($_) -> true;
+is_unreserved($~) -> true;
+is_unreserved(Char) -> is_alpha(Char) orelse is_digit(Char).
+
+-spec is_alpha(char()) -> boolean().
+is_alpha(C)
+  when $A =< C, C =< $Z;
+       $a =< C, C =< $z -> true;
+is_alpha(_) -> false.
+
+-spec is_digit(char()) -> boolean().
+is_digit(C)
+  when $0 =< C, C =< $9 -> true;
+is_digit(_) -> false.
+
+-spec is_hex_digit(char()) -> boolean().
+is_hex_digit(C)
+  when $0 =< C, C =< $9;$a =< C, C =< $f;$A =< C, C =< $F -> true;
+is_hex_digit(_) -> false.
+
+
+%% Remove enclosing brackets from binary
+-spec remove_brackets(binary()) -> binary().
+remove_brackets(<<$[/utf8, Rest/binary>>) ->
+    {H,T} = split_binary(Rest, byte_size(Rest) - 1),
+    case T =:= <<$]/utf8>> of
+        true -> H;
+        false -> Rest
+    end;
+remove_brackets(Addr) -> Addr.
+
+
+%%-------------------------------------------------------------------------
+%% Helper functions for calculating the parsed binary.
+%%-------------------------------------------------------------------------
+-spec calculate_parsed_scheme(binary(), binary()) -> binary().
+calculate_parsed_scheme(Input, <<>>) ->
+    strip_last_char(Input, [$:]);
+calculate_parsed_scheme(Input, Unparsed) ->
+    get_parsed_binary(Input, Unparsed).
+
+
+-spec calculate_parsed_part(binary(), binary()) -> binary().
+calculate_parsed_part(Input, <<>>) ->
+    strip_last_char(Input, [$?,$#]);
+calculate_parsed_part(Input, Unparsed) ->
+    get_parsed_binary(Input, Unparsed).
+
+
+-spec calculate_parsed_userinfo(binary(), binary()) -> binary().
+calculate_parsed_userinfo(Input, <<>>) ->
+    strip_last_char(Input, [$?,$#,$@]);
+calculate_parsed_userinfo(Input, Unparsed) ->
+    get_parsed_binary(Input, Unparsed).
+
+
+-spec calculate_parsed_host_port(binary(), binary()) -> binary().
+calculate_parsed_host_port(Input, <<>>) ->
+    strip_last_char(Input, [$:,$?,$#,$/]);
+calculate_parsed_host_port(Input, Unparsed) ->
+    get_parsed_binary(Input, Unparsed).
+
+
+calculate_parsed_query_fragment(Input, <<>>) ->
+    strip_last_char(Input, [$#]);
+calculate_parsed_query_fragment(Input, Unparsed) ->
+    get_parsed_binary(Input, Unparsed).
+
+
+get_port(<<>>) ->
+    undefined;
+get_port(B) ->
+    try binary_to_integer(B)
+    catch
+        error:badarg ->
+            throw({error, invalid_uri, B})
+    end.
+
+
+%% Strip last char if it is in list
+%%
+%% This function is optimized for speed: parse/1 is about 10% faster than
+%% with an alternative implementation based on lists and sets.
+strip_last_char(<<>>, _) -> <<>>;
+strip_last_char(Input, [C0]) ->
+    case binary:last(Input) of
+        C0 ->
+            init_binary(Input);
+        _Else ->
+            Input
+    end;
+strip_last_char(Input, [C0,C1]) ->
+    case binary:last(Input) of
+        C0 ->
+            init_binary(Input);
+        C1 ->
+            init_binary(Input);
+        _Else ->
+            Input
+    end;
+strip_last_char(Input, [C0,C1,C2]) ->
+    case binary:last(Input) of
+        C0 ->
+            init_binary(Input);
+        C1 ->
+            init_binary(Input);
+        C2 ->
+            init_binary(Input);
+        _Else ->
+            Input
+    end;
+strip_last_char(Input, [C0,C1,C2,C3]) ->
+    case binary:last(Input) of
+        C0 ->
+            init_binary(Input);
+        C1 ->
+            init_binary(Input);
+        C2 ->
+            init_binary(Input);
+        C3 ->
+            init_binary(Input);
+        _Else ->
+            Input
+    end.
+
+
+%% Get parsed binary
+get_parsed_binary(Input, Unparsed) ->
+    {First, _} = split_binary(Input, byte_size(Input) - byte_size_exl_head(Unparsed)),
+    First.
+
+
+%% Return all bytes of the binary except the last one. The binary must be non-empty.
+init_binary(B) ->
+    {Init, _} =
+        split_binary(B, byte_size(B) - 1),
+    Init.
+
+
+%% Returns the size of a binary exluding the first element.
+%% Used in calls to split_binary().
+-spec byte_size_exl_head(binary()) -> number().
+byte_size_exl_head(<<>>) -> 0;
+byte_size_exl_head(Binary) -> byte_size(Binary) + 1.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 2.1.  Percent-Encoding]
+%%
+%% A percent-encoding mechanism is used to represent a data octet in a
+%% component when that octet's corresponding character is outside the
+%% allowed set or is being used as a delimiter of, or within, the
+%% component.  A percent-encoded octet is encoded as a character
+%% triplet, consisting of the percent character "%" followed by the two
+%% hexadecimal digits representing that octet's numeric value.  For
+%% example, "%20" is the percent-encoding for the binary octet
+%% "00100000" (ABNF: %x20), which in US-ASCII corresponds to the space
+%% character (SP).  Section 2.4 describes when percent-encoding and
+%% decoding is applied.
+%%
+%%   pct-encoded = "%" HEXDIG HEXDIG
+%%-------------------------------------------------------------------------
+-spec decode_userinfo(binary()) -> binary().
+decode_userinfo(Cs) ->
+    check_utf8(decode(Cs, fun is_userinfo/1, <<>>)).
+
+-spec decode_host(binary()) -> binary().
+decode_host(Cs) ->
+    check_utf8(decode(Cs, fun is_host/1, <<>>)).
+
+-spec decode_path(binary()) -> binary().
+decode_path(Cs) ->
+    check_utf8(decode(Cs, fun is_path/1, <<>>)).
+
+-spec decode_query(binary()) -> binary().
+decode_query(Cs) ->
+    check_utf8(decode(Cs, fun is_query/1, <<>>)).
+
+-spec decode_fragment(binary()) -> binary().
+decode_fragment(Cs) ->
+    check_utf8(decode(Cs, fun is_fragment/1, <<>>)).
+
+
+%% Returns Cs if it is utf8 encoded.
+check_utf8(Cs) ->
+    case unicode:characters_to_list(Cs) of
+        {incomplete,_,_} ->
+            throw({error,invalid_utf8,Cs});
+        {error,_,_} ->
+            throw({error,invalid_utf8,Cs});
+        _ -> Cs
+    end.
+
+%%-------------------------------------------------------------------------
+%% Percent-encode
+%%-------------------------------------------------------------------------
+
+%% Only validates as scheme cannot have percent-encoded characters
+-spec encode_scheme(list()|binary()) -> list() | binary().
+encode_scheme([]) ->
+    throw({error,invalid_scheme,""});
+encode_scheme(<<>>) ->
+    throw({error,invalid_scheme,<<>>});
+encode_scheme(Scheme) ->
+    case validate_scheme(Scheme) of
+        true -> Scheme;
+        false -> throw({error,invalid_scheme,Scheme})
+    end.
+
+-spec encode_userinfo(list()|binary()) -> list() | binary().
+encode_userinfo(Cs) ->
+    encode(Cs, fun is_userinfo/1).
+
+-spec encode_host(list()|binary()) -> list() | binary().
+encode_host(Cs) ->
+    case classify_host(Cs) of
+        regname -> Cs;
+        ipv4 -> Cs;
+        ipv6 -> bracket_ipv6(Cs);
+        other -> encode(Cs, fun is_reg_name/1)
+    end.
+
+-spec encode_path(list()|binary()) -> list() | binary().
+encode_path(Cs) ->
+    encode(Cs, fun is_path/1).
+
+-spec encode_query(list()|binary()) -> list() | binary().
+encode_query(Cs) ->
+    encode(Cs, fun is_query/1).
+
+-spec encode_fragment(list()|binary()) -> list() | binary().
+encode_fragment(Cs) ->
+    encode(Cs, fun is_fragment/1).
+
+%%-------------------------------------------------------------------------
+%% Helper funtions for percent-decode
+%%-------------------------------------------------------------------------
+decode(<<$%,C0,C1,Cs/binary>>, Fun, Acc) ->
+    case is_hex_digit(C0) andalso is_hex_digit(C1) of
+        true ->
+            B = ?HEX2DEC(C0)*16+?HEX2DEC(C1),
+            decode(Cs, Fun, <<Acc/binary, B>>);
+        false -> throw({error,invalid_percent_encoding,<<$%,C0,C1>>})
+    end;
+decode(<<C,Cs/binary>>, Fun, Acc) ->
+    case Fun(C) of
+        true -> decode(Cs, Fun, <<Acc/binary, C>>);
+        false -> throw({error,invalid_percent_encoding,<<C,Cs/binary>>})
+    end;
+decode(<<>>, _Fun, Acc) ->
+    Acc.
+
+%% Check if char is allowed in host
+-spec is_host(char()) -> boolean().
+is_host($:) -> true;
+is_host(Char) -> is_unreserved(Char) orelse is_sub_delim(Char).
+
+%% Check if char is allowed in path
+-spec is_path(char()) -> boolean().
+is_path($/) -> true;
+is_path(Char) -> is_pchar(Char).
+
+
+%%-------------------------------------------------------------------------
+%% Helper functions for percent-encode
+%%-------------------------------------------------------------------------
+-spec encode(list()|binary(), fun()) -> list() | binary().
+encode(Component, Fun) when is_list(Component) ->
+    B = unicode:characters_to_binary(Component),
+    unicode:characters_to_list(encode(B, Fun, <<>>));
+encode(Component, Fun) when is_binary(Component) ->
+    encode(Component, Fun, <<>>).
+%%
+encode(<<Char/utf8, Rest/binary>>, Fun, Acc) ->
+    C = encode_codepoint_binary(Char, Fun),
+    encode(Rest, Fun, <<Acc/binary,C/binary>>);
+encode(<<Char, Rest/binary>>, _Fun, _Acc) ->
+    throw({error,invalid_input,<<Char,Rest/binary>>});
+encode(<<>>, _Fun, Acc) ->
+    Acc.
+
+
+-spec encode_codepoint_binary(integer(), fun()) -> binary().
+encode_codepoint_binary(C, Fun) ->
+    case Fun(C) of
+        false -> percent_encode_binary(C);
+        true -> <<C>>
+    end.
+
+
+-spec percent_encode_binary(integer()) -> binary().
+percent_encode_binary(Code) ->
+    percent_encode_binary(<<Code/utf8>>, <<>>).
+
+
+percent_encode_binary(<<A:4,B:4,Rest/binary>>, Acc) ->
+    percent_encode_binary(Rest, <<Acc/binary,$%,(?DEC2HEX(A)),(?DEC2HEX(B))>>);
+percent_encode_binary(<<>>, Acc) ->
+    Acc.
+
+
+%%-------------------------------------------------------------------------
+%%-------------------------------------------------------------------------
+validate_scheme([]) -> true;
+validate_scheme([H|T]) ->
+    case is_scheme(H) of
+        true -> validate_scheme(T);
+        false -> false
+    end;
+validate_scheme(<<>>) -> true;
+validate_scheme(<<H, Rest/binary>>) ->
+    case is_scheme(H) of
+        true -> validate_scheme(Rest);
+        false -> false
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% Classifies hostname into the following categories:
+%% regname, ipv4 - address does not contain reserved characters to be
+%%           percent-encoded
+%% ipv6 - address does not contain reserved characters but it shall be
+%%        encolsed in brackets
+%% other - address shall be percent-encoded
+%%-------------------------------------------------------------------------
+classify_host([]) -> other;
+classify_host(Addr) when is_binary(Addr) ->
+    A = unicode:characters_to_list(Addr),
+    classify_host_ipv6(A);
+classify_host(Addr) ->
+    classify_host_ipv6(Addr).
+
+classify_host_ipv6(Addr) ->
+    case is_ipv6_address(Addr) of
+        true -> ipv6;
+        false -> classify_host_ipv4(Addr)
+    end.
+
+classify_host_ipv4(Addr) ->
+    case is_ipv4_address(Addr) of
+        true -> ipv4;
+        false -> classify_host_regname(Addr)
+    end.
+
+classify_host_regname([]) -> regname;
+classify_host_regname([H|T]) ->
+    case is_reg_name(H) of
+        true -> classify_host_regname(T);
+        false -> other
+    end.
+
+is_ipv4_address(Addr) ->
+    case inet:parse_ipv4strict_address(Addr) of
+        {ok, _} -> true;
+        {error, _} -> false
+    end.
+
+is_ipv6_address(Addr) ->
+    case inet:parse_ipv6strict_address(Addr) of
+        {ok, _} -> true;
+        {error, _} -> false
+    end.
+
+bracket_ipv6(Addr) when is_binary(Addr) ->
+    concat(<<$[,Addr/binary>>,<<$]>>);
+bracket_ipv6(Addr) when is_list(Addr) ->
+    [$[|Addr] ++ "]".
+
+
+%%-------------------------------------------------------------------------
+%% Helper funtions for recompose
+%%-------------------------------------------------------------------------
+
+%%-------------------------------------------------------------------------
+%% Checks if input Map has valid combination of fields that can be
+%% recomposed into a URI.
+%%
+%% The implementation is based on a decision tree that fulfills the
+%% following rules:
+%%   - 'path' shall always be present in the input map
+%%       URI         = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
+%%       hier-part   = "//" authority path-abempty
+%%                      / path-absolute
+%%                      / path-rootless
+%%                      / path-empty
+%%   - 'host' shall be present in the input map when 'path' starts with
+%%     two slashes ("//")
+%%       path          = path-abempty    ; begins with "/" or is empty
+%%                     / path-absolute   ; begins with "/" but not "//"
+%%                     / path-noscheme   ; begins with a non-colon segment
+%%                     / path-rootless   ; begins with a segment
+%%                     / path-empty      ; zero characters
+%%       path-abempty  = *( "/" segment )
+%%       segment       = *pchar
+%%   - 'host' shall be present if userinfo or port is present in input map
+%%       authority   = [ userinfo "@" ] host [ ":" port ]
+%%   - All fields shall be valid (scheme, userinfo, host, port, path, query
+%%     or fragment).
+%%-------------------------------------------------------------------------
+is_valid_map(#{path := Path} = Map) ->
+    ((starts_with_two_slash(Path) andalso is_valid_map_host(Map))
+     orelse
+       (maps:is_key(userinfo, Map) andalso is_valid_map_host(Map))
+     orelse
+       (maps:is_key(port, Map) andalso is_valid_map_host(Map))
+     orelse
+     all_fields_valid(Map));
+is_valid_map(#{}) ->
+    false.
+
+
+is_valid_map_host(Map) ->
+    maps:is_key(host, Map) andalso all_fields_valid(Map).
+
+
+all_fields_valid(Map) ->
+    Fun = fun(scheme, _, Acc) -> Acc;
+             (userinfo, _, Acc) -> Acc;
+             (host, _, Acc) -> Acc;
+             (port, _, Acc) -> Acc;
+             (path, _, Acc) -> Acc;
+             (query, _, Acc) -> Acc;
+             (fragment, _, Acc) -> Acc;
+             (_, _, _) -> false
+          end,
+    maps:fold(Fun, true, Map).
+
+
+starts_with_two_slash([$/,$/|_]) ->
+    true;
+starts_with_two_slash(?STRING_REST("//", _)) ->
+    true;
+starts_with_two_slash(_) -> false.
+
+
+update_scheme(#{scheme := Scheme}, _) ->
+    add_colon_postfix(encode_scheme(Scheme));
+update_scheme(#{}, _) ->
+    empty.
+
+
+update_userinfo(#{userinfo := Userinfo}, empty) ->
+    add_auth_prefix(encode_userinfo(Userinfo));
+update_userinfo(#{userinfo := Userinfo}, URI) ->
+    concat(URI,add_auth_prefix(encode_userinfo(Userinfo)));
+update_userinfo(#{}, empty) ->
+    empty;
+update_userinfo(#{}, URI) ->
+    URI.
+
+
+update_host(#{host := Host}, empty) ->
+    add_auth_prefix(encode_host(Host));
+update_host(#{host := Host} = Map, URI) ->
+    concat(URI,add_host_prefix(Map, encode_host(Host)));
+update_host(#{}, empty) ->
+    empty;
+update_host(#{}, URI) ->
+    URI.
+
+
+%% URI cannot be empty for ports. E.g. ":8080" is not a valid URI
+update_port(#{port := undefined}, URI) ->
+    concat(URI, <<":">>);
+update_port(#{port := Port}, URI) ->
+    concat(URI,add_colon(encode_port(Port)));
+update_port(#{}, URI) ->
+    URI.
+
+
+update_path(#{path := Path}, empty) ->
+    encode_path(Path);
+update_path(#{path := Path}, URI) ->
+    concat(URI,encode_path(Path));
+update_path(#{}, empty) ->
+    empty;
+update_path(#{}, URI) ->
+    URI.
+
+
+update_query(#{query := Query}, empty) ->
+    encode_query(Query);
+update_query(#{query := Query}, URI) ->
+    concat(URI,add_question_mark(encode_query(Query)));
+update_query(#{}, empty) ->
+    empty;
+update_query(#{}, URI) ->
+    URI.
+
+
+update_fragment(#{fragment := Fragment}, empty) ->
+    add_hashmark(encode_fragment(Fragment));
+update_fragment(#{fragment := Fragment}, URI) ->
+    concat(URI,add_hashmark(encode_fragment(Fragment)));
+update_fragment(#{}, empty) ->
+    "";
+update_fragment(#{}, URI) ->
+    URI.
+
+%%-------------------------------------------------------------------------
+%% Concatenates its arguments that can be lists and binaries.
+%% The result is a list if at least one of its argument is a list and
+%% binary otherwise.
+%%-------------------------------------------------------------------------
+concat(A, B) when is_binary(A), is_binary(B) ->
+    <<A/binary, B/binary>>;
+concat(A, B) when is_binary(A), is_list(B) ->
+    unicode:characters_to_list(A) ++ B;
+concat(A, B) when is_list(A) ->
+    A ++ maybe_to_list(B).
+
+add_hashmark(Comp) when is_binary(Comp) ->
+    <<$#, Comp/binary>>;
+add_hashmark(Comp) when is_list(Comp) ->
+    [$#|Comp].
+
+add_question_mark(Comp) when is_binary(Comp) ->
+    <<$?, Comp/binary>>;
+add_question_mark(Comp) when is_list(Comp) ->
+    [$?|Comp].
+
+add_colon(Comp) when is_binary(Comp) ->
+    <<$:, Comp/binary>>.
+
+add_colon_postfix(Comp) when is_binary(Comp) ->
+    <<Comp/binary,$:>>;
+add_colon_postfix(Comp) when is_list(Comp) ->
+    Comp ++ ":".
+
+add_auth_prefix(Comp) when is_binary(Comp) ->
+    <<"//", Comp/binary>>;
+add_auth_prefix(Comp) when is_list(Comp) ->
+    [$/,$/|Comp].
+
+add_host_prefix(#{userinfo := _}, Host) when is_binary(Host) ->
+    <<$@,Host/binary>>;
+add_host_prefix(#{}, Host) when is_binary(Host) ->
+    <<"//",Host/binary>>;
+add_host_prefix(#{userinfo := _}, Host) when is_list(Host) ->
+    [$@|Host];
+add_host_prefix(#{}, Host) when is_list(Host) ->
+    [$/,$/|Host].
+
+maybe_to_list(Comp) when is_binary(Comp) -> unicode:characters_to_list(Comp);
+maybe_to_list(Comp) -> Comp.
+
+encode_port(Port) ->
+    integer_to_binary(Port).
+
+%%-------------------------------------------------------------------------
+%% Helper functions for transcode
+%%-------------------------------------------------------------------------
+
+%%-------------------------------------------------------------------------
+%% uri_string:transcode(<<"x%00%00%00%F6"/utf32>>).
+%% 1. Convert (transcode/2) input to list form (list of unicode codepoints)
+%%    "x%00%00%00%F6"
+%% 2. Accumulate characters until percent-encoded segment (transcode/4).
+%%    Acc = "x"
+%% 3. Convert percent-encoded triplets to binary form (transcode_pct/4)
+%%    <<0,0,0,246>>
+%% 4. Transcode in-encoded binary to out-encoding (utf32 -> utf8):
+%%    <<195,182>>
+%% 5. Percent-encode out-encoded binary:
+%%    <<"%C3%B6"/utf8>> = <<37,67,51,37,66,54>>
+%% 6. Convert binary to list form, reverse it and append the accumulator
+%%    "6B%3C%" + "x"
+%% 7. Reverse Acc and return it
+%%-------------------------------------------------------------------------
+transcode([$%,_C0,_C1|_Rest] = L, Acc, InEnc, OutEnc) ->
+    transcode_pct(L, Acc, <<>>, InEnc, OutEnc);
+transcode([_C|_Rest] = L, Acc, InEnc, OutEnc) ->
+    transcode(L, Acc, [], InEnc, OutEnc).
+%%
+transcode([$%,_C0,_C1|_Rest] = L, Acc, List, InEncoding, OutEncoding) ->
+    transcode_pct(L, List ++ Acc, <<>>, InEncoding, OutEncoding);
+transcode([C|Rest], Acc, List, InEncoding, OutEncoding) ->
+    transcode(Rest, Acc, [C|List], InEncoding, OutEncoding);
+transcode([], Acc, List, _InEncoding, _OutEncoding) ->
+    lists:reverse(List ++ Acc).
+
+
+%% Transcode percent-encoded segment
+transcode_pct([$%,C0,C1|Rest] = L, Acc, B, InEncoding, OutEncoding) ->
+    case is_hex_digit(C0) andalso is_hex_digit(C1) of
+        true ->
+            Int = ?HEX2DEC(C0)*16+?HEX2DEC(C1),
+            transcode_pct(Rest, Acc, <<B/binary, Int>>, InEncoding, OutEncoding);
+        false -> throw({error, invalid_percent_encoding,L})
+    end;
+transcode_pct([_C|_Rest] = L, Acc, B, InEncoding, OutEncoding) ->
+    OutBinary = convert_to_binary(B, InEncoding, OutEncoding),
+    PctEncUtf8 = percent_encode_segment(OutBinary),
+    Out = lists:reverse(convert_to_list(PctEncUtf8, utf8)),
+    transcode(L, Out ++ Acc, [], InEncoding, OutEncoding);
+transcode_pct([], Acc, B, InEncoding, OutEncoding) ->
+    OutBinary = convert_to_binary(B, InEncoding, OutEncoding),
+    PctEncUtf8 = percent_encode_segment(OutBinary),
+    Out = convert_to_list(PctEncUtf8, utf8),
+    lists:reverse(Acc) ++ Out.
+
+
+%% Convert to binary
+convert_to_binary(Binary, InEncoding, OutEncoding) ->
+    case unicode:characters_to_binary(Binary, InEncoding, OutEncoding) of
+        {error, _List, RestData} ->
+            throw({error, invalid_input, RestData});
+        {incomplete, _List, RestData} ->
+            throw({error, invalid_input, RestData});
+        Result ->
+            Result
+    end.
+
+
+%% Convert to list
+convert_to_list(Binary, InEncoding) ->
+    case unicode:characters_to_list(Binary, InEncoding) of
+        {error, _List, RestData} ->
+            throw({error, invalid_input, RestData});
+        {incomplete, _List, RestData} ->
+            throw({error, invalid_input, RestData});
+        Result ->
+            Result
+    end.
+
+
+%% Flatten input list
+flatten_list([], _) ->
+    [];
+flatten_list(L, InEnc) ->
+    flatten_list(L, InEnc, []).
+%%
+flatten_list([H|T], InEnc, Acc) when is_binary(H) ->
+    L = convert_to_list(H, InEnc),
+    flatten_list(T, InEnc, lists:reverse(L) ++ Acc);
+flatten_list([H|T], InEnc, Acc) when is_list(H) ->
+    flatten_list(H ++ T, InEnc, Acc);
+flatten_list([H|T], InEnc, Acc) ->
+    flatten_list(T, InEnc, [H|Acc]);
+flatten_list([], _InEnc, Acc) ->
+    lists:reverse(Acc);
+flatten_list(Arg, _, _) ->
+    throw({error, invalid_input, Arg}).
+
+
+percent_encode_segment(Segment) ->
+    percent_encode_binary(Segment, <<>>).
+
+
+%%-------------------------------------------------------------------------
+%% Helper functions for compose_query
+%%-------------------------------------------------------------------------
+
+%% Returns separator to be used between key-value pairs
+get_separator(L) when length(L) =:= 0 ->
+    <<>>;
+get_separator(_L) ->
+    <<"&">>.
+
+
+%% HTML5 - 4.10.22.6 URL-encoded form data - encoding
+form_urlencode(Cs, [{encoding, latin1}]) when is_list(Cs) ->
+    B = convert_to_binary(Cs, utf8, utf8),
+    html5_byte_encode(base10_encode(B));
+form_urlencode(Cs, [{encoding, latin1}]) when is_binary(Cs) ->
+    html5_byte_encode(base10_encode(Cs));
+form_urlencode(Cs, [{encoding, Encoding}])
+  when is_list(Cs), Encoding =:= utf8; Encoding =:= unicode ->
+    B = convert_to_binary(Cs, utf8, Encoding),
+    html5_byte_encode(B);
+form_urlencode(Cs, [{encoding, Encoding}])
+  when is_binary(Cs), Encoding =:= utf8; Encoding =:= unicode ->
+    html5_byte_encode(Cs);
+form_urlencode(Cs, [{encoding, Encoding}]) when is_list(Cs); is_binary(Cs) ->
+    throw({error,invalid_encoding, Encoding});
+form_urlencode(Cs, _) ->
+    throw({error,invalid_input, Cs}).
+
+
+%% For each character in the entry's name and value that cannot be expressed using
+%% the selected character encoding, replace the character by a string consisting of
+%% a U+0026 AMPERSAND character (&), a "#" (U+0023) character, one or more ASCII
+%% digits representing the Unicode code point of the character in base ten, and
+%% finally a ";" (U+003B) character.
+base10_encode(Cs) ->
+    base10_encode(Cs, <<>>).
+%%
+base10_encode(<<>>, Acc) ->
+    Acc;
+base10_encode(<<H/utf8,T/binary>>, Acc) when H > 255 ->
+    Base10 = convert_to_binary(integer_to_list(H,10), utf8, utf8),
+    base10_encode(T, <<Acc/binary,"&#",Base10/binary,$;>>);
+base10_encode(<<H/utf8,T/binary>>, Acc) ->
+    base10_encode(T, <<Acc/binary,H>>).
+
+
+html5_byte_encode(B) ->
+    html5_byte_encode(B, <<>>).
+%%
+html5_byte_encode(<<>>, Acc) ->
+    Acc;
+html5_byte_encode(<<$ ,T/binary>>, Acc) ->
+    html5_byte_encode(T, <<Acc/binary,$+>>);
+html5_byte_encode(<<H,T/binary>>, Acc) ->
+    case is_url_char(H) of
+        true ->
+            html5_byte_encode(T, <<Acc/binary,H>>);
+        false ->
+            <<A:4,B:4>> = <<H>>,
+            html5_byte_encode(T, <<Acc/binary,$%,(?DEC2HEX(A)),(?DEC2HEX(B))>>)
+    end;
+html5_byte_encode(H, _Acc) ->
+    throw({error,invalid_input, H}).
+
+
+%% Return true if input char can appear in form-urlencoded string
+%% Allowed chararacters:
+%%   0x2A, 0x2D, 0x2E, 0x30 to 0x39, 0x41 to 0x5A,
+%%   0x5F, 0x61 to 0x7A
+is_url_char(C)
+  when C =:= 16#2A; C =:= 16#2D;
+       C =:= 16#2E; C =:= 16#5F;
+       16#30 =< C, C =< 16#39;
+       16#41 =< C, C =< 16#5A;
+       16#61 =< C, C =< 16#7A -> true;
+is_url_char(_) -> false.
+
+
+%%-------------------------------------------------------------------------
+%% Helper functions for dissect_query
+%%-------------------------------------------------------------------------
+dissect_query_key(<<$=,T/binary>>, IsList, Acc, Key, Value) ->
+    dissect_query_value(T, IsList, Acc, Key, Value);
+dissect_query_key(<<"&#",T/binary>>, IsList, Acc, Key, Value) ->
+    dissect_query_key(T, IsList, Acc, <<Key/binary,"&#">>, Value);
+dissect_query_key(<<$&,_T/binary>>, _IsList, _Acc, _Key, _Value) ->
+    throw({error, missing_value, "&"});
+dissect_query_key(<<H,T/binary>>, IsList, Acc, Key, Value) ->
+    dissect_query_key(T, IsList, Acc, <<Key/binary,H>>, Value);
+dissect_query_key(B, _, _, _, _) ->
+    throw({error, missing_value, B}).
+
+
+dissect_query_value(<<$&,T/binary>>, IsList, Acc, Key, Value) ->
+    K = form_urldecode(IsList, Key),
+    V = form_urldecode(IsList, Value),
+    dissect_query_key(T, IsList, [{K,V}|Acc], <<>>, <<>>);
+dissect_query_value(<<H,T/binary>>, IsList, Acc, Key, Value) ->
+    dissect_query_value(T, IsList, Acc, Key, <<Value/binary,H>>);
+dissect_query_value(<<>>, IsList, Acc, Key, Value) ->
+    K = form_urldecode(IsList, Key),
+    V = form_urldecode(IsList, Value),
+    lists:reverse([{K,V}|Acc]).
+
+
+%% Form-urldecode input based on RFC 1866 [8.2.1]
+form_urldecode(true, B) ->
+    Result = base10_decode(form_urldecode(B, <<>>)),
+    convert_to_list(Result, utf8);
+form_urldecode(false, B) ->
+    base10_decode(form_urldecode(B, <<>>));
+form_urldecode(<<>>, Acc) ->
+    Acc;
+form_urldecode(<<$+,T/binary>>, Acc) ->
+    form_urldecode(T, <<Acc/binary,$ >>);
+form_urldecode(<<$%,C0,C1,T/binary>>, Acc) ->
+    case is_hex_digit(C0) andalso is_hex_digit(C1) of
+        true ->
+            V = ?HEX2DEC(C0)*16+?HEX2DEC(C1),
+            form_urldecode(T, <<Acc/binary, V>>);
+        false ->
+            L = convert_to_list(<<$%,C0,C1,T/binary>>, utf8),
+            throw({error, invalid_percent_encoding, L})
+    end;
+form_urldecode(<<H/utf8,T/binary>>, Acc) ->
+    form_urldecode(T, <<Acc/binary,H/utf8>>);
+form_urldecode(<<H,_/binary>>, _Acc) ->
+    throw({error, invalid_character, [H]}).
+
+base10_decode(Cs) ->
+    base10_decode(Cs, <<>>).
+%
+base10_decode(<<>>, Acc) ->
+    Acc;
+base10_decode(<<"&#",T/binary>>, Acc) ->
+    base10_decode_unicode(T, Acc);
+base10_decode(<<H/utf8,T/binary>>, Acc) ->
+    base10_decode(T,<<Acc/binary,H/utf8>>);
+base10_decode(<<H,_/binary>>, _) ->
+    throw({error, invalid_input, [H]}).
+
+
+base10_decode_unicode(B, Acc) ->
+    base10_decode_unicode(B, 0, Acc).
+%%
+base10_decode_unicode(<<H/utf8,T/binary>>, Codepoint, Acc) when $0 =< H, H =< $9 ->
+    Res = Codepoint * 10 + (H - $0),
+    base10_decode_unicode(T, Res, Acc);
+base10_decode_unicode(<<$;,T/binary>>, Codepoint, Acc) ->
+    base10_decode(T, <<Acc/binary,Codepoint/utf8>>);
+base10_decode_unicode(<<H,_/binary>>, _, _) ->
+    throw({error, invalid_input, [H]}).
+
+
+%%-------------------------------------------------------------------------
+%% Helper functions for normalize
+%%-------------------------------------------------------------------------
+
+%% 6.2.2.1.  Case Normalization
+normalize_case(#{scheme := Scheme, host := Host} = Map) ->
+    Map#{scheme => to_lower(Scheme),
+         host => to_lower(Host)};
+normalize_case(#{host := Host} = Map) ->
+    Map#{host => to_lower(Host)};
+normalize_case(#{scheme := Scheme} = Map) ->
+    Map#{scheme => to_lower(Scheme)};
+normalize_case(#{} = Map) ->
+    Map.
+
+
+to_lower(Cs) when is_list(Cs) ->
+    B = convert_to_binary(Cs, utf8, utf8),
+    convert_to_list(to_lower(B), utf8);
+to_lower(Cs) when is_binary(Cs) ->
+    to_lower(Cs, <<>>).
+%%
+to_lower(<<C,Cs/binary>>, Acc) when $A =< C, C =< $Z ->
+    to_lower(Cs, <<Acc/binary,(C + 32)>>);
+to_lower(<<C,Cs/binary>>, Acc) ->
+    to_lower(Cs, <<Acc/binary,C>>);
+to_lower(<<>>, Acc) ->
+    Acc.
+
+
+%% 6.2.2.3. Path Segment Normalization
+%% 5.2.4.   Remove Dot Segments
+normalize_path_segment(Map) ->
+    Path = maps:get(path, Map, undefined),
+    Map#{path => remove_dot_segments(Path)}.
+
+
+remove_dot_segments(Path) when is_binary(Path) ->
+    remove_dot_segments(Path, <<>>);
+remove_dot_segments(Path) when is_list(Path) ->
+    B = convert_to_binary(Path, utf8, utf8),
+    B1 = remove_dot_segments(B, <<>>),
+    convert_to_list(B1, utf8).
+%%
+remove_dot_segments(<<>>, Output) ->
+    Output;
+remove_dot_segments(<<"../",T/binary>>, Output) ->
+    remove_dot_segments(T, Output);
+remove_dot_segments(<<"./",T/binary>>, Output) ->
+    remove_dot_segments(T, Output);
+remove_dot_segments(<<"/./",T/binary>>, Output) ->
+    remove_dot_segments(<<$/,T/binary>>, Output);
+remove_dot_segments(<<"/.">>, Output) ->
+    remove_dot_segments(<<$/>>, Output);
+remove_dot_segments(<<"/../",T/binary>>, Output) ->
+    Out1 = remove_last_segment(Output),
+    remove_dot_segments(<<$/,T/binary>>, Out1);
+remove_dot_segments(<<"/..">>, Output) ->
+    Out1 = remove_last_segment(Output),
+    remove_dot_segments(<<$/>>, Out1);
+remove_dot_segments(<<$.>>, Output) ->
+    remove_dot_segments(<<>>, Output);
+remove_dot_segments(<<"..">>, Output) ->
+    remove_dot_segments(<<>>, Output);
+remove_dot_segments(Input, Output) ->
+    {First, Rest} = first_path_segment(Input),
+    remove_dot_segments(Rest, <<Output/binary,First/binary>>).
+
+
+first_path_segment(Input) ->
+    F = first_path_segment(Input, <<>>),
+    split_binary(Input, byte_size(F)).
+%%
+first_path_segment(<<$/,T/binary>>, Acc) ->
+    first_path_segment_end(<<T/binary>>, <<Acc/binary,$/>>);
+first_path_segment(<<C,T/binary>>, Acc) ->
+    first_path_segment_end(<<T/binary>>, <<Acc/binary,C>>).
+
+
+first_path_segment_end(<<>>, Acc) ->
+    Acc;
+first_path_segment_end(<<$/,_/binary>>, Acc) ->
+    Acc;
+first_path_segment_end(<<C,T/binary>>, Acc) ->
+    first_path_segment_end(<<T/binary>>, <<Acc/binary,C>>).
+
+
+remove_last_segment(<<>>) ->
+    <<>>;
+remove_last_segment(B) ->
+    {Init, Last} = split_binary(B, byte_size(B) - 1),
+    case Last of
+        <<$/>> ->
+            Init;
+        _Char ->
+            remove_last_segment(Init)
+    end.
+
+
+%% RFC 3986, 6.2.3.  Scheme-Based Normalization
+normalize_scheme_based(Map) ->
+    Scheme = maps:get(scheme, Map, undefined),
+    Port = maps:get(port, Map, undefined),
+    Path= maps:get(path, Map, undefined),
+    normalize_scheme_based(Map, Scheme, Port, Path).
+%%
+normalize_scheme_based(Map, Scheme, Port, Path)
+  when Scheme =:= "http"; Scheme =:= <<"http">> ->
+    normalize_http(Map, Port, Path);
+normalize_scheme_based(Map, Scheme, Port, Path)
+  when Scheme =:= "https"; Scheme =:= <<"https">> ->
+    normalize_https(Map, Port, Path);
+normalize_scheme_based(Map, Scheme, Port, _Path)
+  when Scheme =:= "ftp"; Scheme =:= <<"ftp">> ->
+    normalize_ftp(Map, Port);
+normalize_scheme_based(Map, Scheme, Port, _Path)
+  when Scheme =:= "ssh"; Scheme =:= <<"ssh">> ->
+    normalize_ssh_sftp(Map, Port);
+normalize_scheme_based(Map, Scheme, Port, _Path)
+  when Scheme =:= "sftp"; Scheme =:= <<"sftp">> ->
+    normalize_ssh_sftp(Map, Port);
+normalize_scheme_based(Map, Scheme, Port, _Path)
+  when Scheme =:= "tftp"; Scheme =:= <<"tftp">> ->
+    normalize_tftp(Map, Port);
+normalize_scheme_based(Map, _, _, _) ->
+    Map.
+
+
+normalize_http(Map, Port, Path) ->
+    M1 = normalize_port(Map, Port, 80),
+    normalize_http_path(M1, Path).
+
+
+normalize_https(Map, Port, Path) ->
+    M1 = normalize_port(Map, Port, 443),
+    normalize_http_path(M1, Path).
+
+
+normalize_ftp(Map, Port) ->
+    normalize_port(Map, Port, 21).
+
+
+normalize_ssh_sftp(Map, Port) ->
+    normalize_port(Map, Port, 22).
+
+
+normalize_tftp(Map, Port) ->
+    normalize_port(Map, Port, 69).
+
+
+normalize_port(Map, Port, Default) ->
+    case Port of
+        Default ->
+            maps:remove(port, Map);
+        _Else ->
+            Map
+    end.
+
+
+normalize_http_path(Map, Path) ->
+    case Path of
+        "" ->
+            Map#{path => "/"};
+        <<>> ->
+            Map#{path => <<"/">>};
+        _Else ->
+            Map
+    end.
diff --git a/lib/stdlib/test/Makefile b/lib/stdlib/test/Makefile
index 7b79dcf04d..8490770f3d 100644
--- a/lib/stdlib/test/Makefile
+++ b/lib/stdlib/test/Makefile
@@ -69,6 +69,7 @@ MODULES= \
 	sets_test_lib \
 	sofs_SUITE \
 	stdlib_SUITE \
+	stdlib_bench_SUITE \
 	string_SUITE \
 	supervisor_1 \
 	supervisor_2 \
@@ -86,6 +87,7 @@ MODULES= \
 	timer_simple_SUITE \
 	unicode_SUITE \
 	unicode_util_SUITE \
+	uri_string_SUITE \
 	win32reg_SUITE \
 	y2k_SUITE \
 	select_SUITE \
@@ -146,7 +148,7 @@ release_spec: opt
 
 release_tests_spec: make_emakefile
 	$(INSTALL_DIR) "$(RELSYSDIR)"
-	$(INSTALL_DATA) stdlib.spec $(EMAKEFILE) \
+	$(INSTALL_DATA) stdlib.spec stdlib_bench.spec $(EMAKEFILE) \
 		$(ERL_FILES) $(COVERFILE) "$(RELSYSDIR)"
 	chmod -R u+w "$(RELSYSDIR)"
 	@tar cf - *_SUITE_data | (cd "$(RELSYSDIR)"; tar xf -)
diff --git a/lib/stdlib/test/base64_SUITE.erl b/lib/stdlib/test/base64_SUITE.erl
index 48b3f5f959..1fc4c3fc0e 100644
--- a/lib/stdlib/test/base64_SUITE.erl
+++ b/lib/stdlib/test/base64_SUITE.erl
@@ -97,10 +97,9 @@ base64_otp_5635(Config) when is_list(Config) ->
     <<"===">> = base64:decode(base64:encode("===")),
     ok.
 %%-------------------------------------------------------------------------
-%% OTP-6279: Guard needed so that function fails in a correct
-%% way for faulty input, i.e. function_clause.
+%% OTP-6279: Make sure illegal characters are rejected when decoding.
 base64_otp_6279(Config) when is_list(Config) ->
-    {'EXIT',{function_clause, _}} = (catch base64:decode("dGVzda==a")),
+    {'EXIT',_} = (catch base64:decode("dGVzda==a")),
     ok.
 %%-------------------------------------------------------------------------
 %% Encode and decode big binaries.
@@ -115,48 +114,61 @@ big(Config) when is_list(Config) ->
 %%-------------------------------------------------------------------------
 %% Make sure illegal characters are rejected when decoding.
 illegal(Config) when is_list(Config) ->
-    {'EXIT',{function_clause, _}} = (catch base64:decode("()")),
+    %% A few samples with different error reasons. Nothing can be
+    %% assumed about the reason for the crash.
+    {'EXIT',_} = (catch base64:decode("()")),
+    {'EXIT',_} = (catch base64:decode(<<19:8,20:8,21:8,22:8>>)),
+    {'EXIT',_} = (catch base64:decode([19,20,21,22])),
+    {'EXIT',_} = (catch base64:decode_to_string(<<19:8,20:8,21:8,22:8>>)),
+    {'EXIT',_} = (catch base64:decode_to_string([19,20,21,22])),
     ok.
 %%-------------------------------------------------------------------------
 %% mime_decode and mime_decode_to_string have different implementations
-%% so test both with the same input separately. Both functions have
-%% the same implementation for binary/string arguments.
+%% so test both with the same input separately.
 %%
 %% Test base64:mime_decode/1.
 mime_decode(Config) when is_list(Config) ->
+    MimeDecode = fun(In) ->
+                         Out = base64:mime_decode(In),
+                         Out = base64:mime_decode(binary_to_list(In))
+                 end,
     %% Test correct padding
-    <<"one">> = base64:mime_decode(<<"b25l">>),
-    <<"on">>  = base64:mime_decode(<<"b24=">>),
-    <<"o">>   = base64:mime_decode(<<"bw==">>),
+    <<"one">> = MimeDecode(<<"b25l">>),
+    <<"on">>  = MimeDecode(<<"b24=">>),
+    <<"o">>   = MimeDecode(<<"bw==">>),
     %% Test 1 extra padding
-    <<"one">> = base64:mime_decode(<<"b25l= =">>),
-    <<"on">>  = base64:mime_decode(<<"b24== =">>),
-    <<"o">>   = base64:mime_decode(<<"bw=== =">>),
+    <<"one">> = MimeDecode(<<"b25l= =">>),
+    <<"on">>  = MimeDecode(<<"b24== =">>),
+    <<"o">>   = MimeDecode(<<"bw=== =">>),
     %% Test 2 extra padding
-    <<"one">> = base64:mime_decode(<<"b25l===">>),
-    <<"on">>  = base64:mime_decode(<<"b24====">>),
-    <<"o">>   = base64:mime_decode(<<"bw=====">>),
+    <<"one">> = MimeDecode(<<"b25l===">>),
+    <<"on">>  = MimeDecode(<<"b24====">>),
+    <<"o">>   = MimeDecode(<<"bw=====">>),
     %% Test misc embedded padding
-    <<"one">> = base64:mime_decode(<<"b2=5l===">>),
-    <<"on">>  = base64:mime_decode(<<"b=24====">>),
-    <<"o">>   = base64:mime_decode(<<"b=w=====">>),
+    <<"one">> = MimeDecode(<<"b2=5l===">>),
+    <<"on">>  = MimeDecode(<<"b=24====">>),
+    <<"o">>   = MimeDecode(<<"b=w=====">>),
     %% Test misc white space and illegals with embedded padding
-    <<"one">> = base64:mime_decode(<<" b~2=\r\n5()l===">>),
-    <<"on">>  = base64:mime_decode(<<"\tb =2\"¤4=¤=   ==">>),
-    <<"o">>   = base64:mime_decode(<<"\nb=w=====">>),
+    <<"one">> = MimeDecode(<<" b~2=\r\n5()l===">>),
+    <<"on">>  = MimeDecode(<<"\tb =2\"¤4=¤=   ==">>),
+    <<"o">>   = MimeDecode(<<"\nb=w=====">>),
     %% Two pads
     <<"Aladdin:open sesame">> =
-	base64:mime_decode("QWxhZGRpbjpvc()GVuIHNlc2FtZQ=="),
+	MimeDecode(<<"QWxhZGRpbjpvc()GVuIHNlc2FtZQ==">>),
     %% One pad to ignore, followed by more text
-    <<"Hello World!!">> = base64:mime_decode(<<"SGVsb)(G8gV29ybGQ=h IQ= =">>),
+    <<"Hello World!!">> = MimeDecode(<<"SGVsb)(G8gV29ybGQ=h IQ= =">>),
     %% No pad
     <<"Aladdin:open sesam">> =
-	base64:mime_decode("QWxhZGRpbjpvcG¤\")(VuIHNlc2Ft"),
+	MimeDecode(<<"QWxhZGRpbjpvcG¤\")(VuIHNlc2Ft">>),
     %% Encoded base 64 strings may be divided by non base 64 chars.
     %% In this cases whitespaces.
     <<"0123456789!@#0^&*();:<>,. []{}">> =
-	base64:mime_decode(
+	MimeDecode(
 	  <<"MDEy MzQ1Njc4 \tOSFAIzBeJ \nio)(oKTs6 PD4sLi \r\nBbXXt9">>),
+    %% Zeroes
+    <<"012">> = MimeDecode(<<"\000M\000D\000E\000y=\000">>),
+    <<"o">>   = MimeDecode(<<"bw==\000">>),
+    <<"o">>   = MimeDecode(<<"bw=\000=">>),
     ok.
 
 %%-------------------------------------------------------------------------
@@ -165,39 +177,48 @@ mime_decode(Config) when is_list(Config) ->
 
 %% Test base64:mime_decode_to_string/1.
 mime_decode_to_string(Config) when is_list(Config) ->
+    MimeDecodeToString =
+        fun(In) ->
+                Out = base64:mime_decode_to_string(In),
+                Out = base64:mime_decode_to_string(binary_to_list(In))
+        end,
     %% Test correct padding
-    "one" = base64:mime_decode_to_string(<<"b25l">>),
-    "on"  = base64:mime_decode_to_string(<<"b24=">>),
-    "o"   = base64:mime_decode_to_string(<<"bw==">>),
+    "one" = MimeDecodeToString(<<"b25l">>),
+    "on"  = MimeDecodeToString(<<"b24=">>),
+    "o"   = MimeDecodeToString(<<"bw==">>),
     %% Test 1 extra padding
-    "one" = base64:mime_decode_to_string(<<"b25l= =">>),
-    "on"  = base64:mime_decode_to_string(<<"b24== =">>),
-    "o"   = base64:mime_decode_to_string(<<"bw=== =">>),
+    "one" = MimeDecodeToString(<<"b25l= =">>),
+    "on"  = MimeDecodeToString(<<"b24== =">>),
+    "o"   = MimeDecodeToString(<<"bw=== =">>),
     %% Test 2 extra padding
-    "one" = base64:mime_decode_to_string(<<"b25l===">>),
-    "on"  = base64:mime_decode_to_string(<<"b24====">>),
-    "o"   = base64:mime_decode_to_string(<<"bw=====">>),
+    "one" = MimeDecodeToString(<<"b25l===">>),
+    "on"  = MimeDecodeToString(<<"b24====">>),
+    "o"   = MimeDecodeToString(<<"bw=====">>),
     %% Test misc embedded padding
-    "one" = base64:mime_decode_to_string(<<"b2=5l===">>),
-    "on"  = base64:mime_decode_to_string(<<"b=24====">>),
-    "o"   = base64:mime_decode_to_string(<<"b=w=====">>),
+    "one" = MimeDecodeToString(<<"b2=5l===">>),
+    "on"  = MimeDecodeToString(<<"b=24====">>),
+    "o"   = MimeDecodeToString(<<"b=w=====">>),
     %% Test misc white space and illegals with embedded padding
-    "one" = base64:mime_decode_to_string(<<" b~2=\r\n5()l===">>),
-    "on"  = base64:mime_decode_to_string(<<"\tb =2\"¤4=¤=   ==">>),
-    "o"   = base64:mime_decode_to_string(<<"\nb=w=====">>),
+    "one" = MimeDecodeToString(<<" b~2=\r\n5()l===">>),
+    "on"  = MimeDecodeToString(<<"\tb =2\"¤4=¤=   ==">>),
+    "o"   = MimeDecodeToString(<<"\nb=w=====">>),
     %% Two pads
     "Aladdin:open sesame" =
-	base64:mime_decode_to_string("QWxhZGRpbjpvc()GVuIHNlc2FtZQ=="),
+	MimeDecodeToString(<<"QWxhZGRpbjpvc()GVuIHNlc2FtZQ==">>),
     %% One pad to ignore, followed by more text
-    "Hello World!!" = base64:mime_decode_to_string(<<"SGVsb)(G8gV29ybGQ=h IQ= =">>),
+    "Hello World!!" = MimeDecodeToString(<<"SGVsb)(G8gV29ybGQ=h IQ= =">>),
     %% No pad
     "Aladdin:open sesam" =
-	base64:mime_decode_to_string("QWxhZGRpbjpvcG¤\")(VuIHNlc2Ft"),
+	MimeDecodeToString(<<"QWxhZGRpbjpvcG¤\")(VuIHNlc2Ft">>),
     %% Encoded base 64 strings may be divided by non base 64 chars.
     %% In this cases whitespaces.
     "0123456789!@#0^&*();:<>,. []{}" =
-	base64:mime_decode_to_string(
+	MimeDecodeToString(
 	  <<"MDEy MzQ1Njc4 \tOSFAIzBeJ \nio)(oKTs6 PD4sLi \r\nBbXXt9">>),
+    %% Zeroes
+    "012" = MimeDecodeToString(<<"\000M\000D\000E\000y=\000">>),
+    "o"   = MimeDecodeToString(<<"bw==\000">>),
+    "o"   = MimeDecodeToString(<<"bw=\000=">>),
     ok.
 
 %%-------------------------------------------------------------------------
diff --git a/lib/stdlib/test/erl_internal_SUITE.erl b/lib/stdlib/test/erl_internal_SUITE.erl
index 789a9d4363..7d9df1f989 100644
--- a/lib/stdlib/test/erl_internal_SUITE.erl
+++ b/lib/stdlib/test/erl_internal_SUITE.erl
@@ -80,7 +80,7 @@ callbacks(application) ->
 callbacks(gen_server) ->
     [{init,1}, {handle_call,3}, {handle_cast,2},
      {handle_info,2}, {terminate,2}, {code_change,3},
-     {format_status,2}];
+     {format_status,2}, {handle_continue, 2}];
 callbacks(gen_fsm) ->
     [{init,1}, {handle_event,3}, {handle_sync_event,4},
      {handle_info,3}, {terminate,3}, {code_change,4},
@@ -101,7 +101,7 @@ callbacks(supervisor) ->
 optional_callbacks(application) ->
     [];
 optional_callbacks(gen_server) ->
-    [{handle_info, 2}, {terminate, 2}, {code_change, 3}, {format_status, 2}];
+    [{handle_info, 2}, {handle_continue, 2}, {terminate, 2}, {code_change, 3}, {format_status, 2}];
 optional_callbacks(gen_fsm) ->
     [{handle_info, 3}, {terminate, 3}, {code_change, 4}, {format_status, 2}];
 optional_callbacks(gen_event) ->
diff --git a/lib/stdlib/test/erl_lint_SUITE.erl b/lib/stdlib/test/erl_lint_SUITE.erl
index b76bece07f..5efffc6a5c 100644
--- a/lib/stdlib/test/erl_lint_SUITE.erl
+++ b/lib/stdlib/test/erl_lint_SUITE.erl
@@ -66,7 +66,8 @@
          otp_11851/1,otp_11879/1,otp_13230/1,
          record_errors/1, otp_11879_cont/1,
          non_latin1_module/1, otp_14323/1,
-         get_stacktrace/1, otp_14285/1, otp_14378/1]).
+         get_stacktrace/1, stacktrace_syntax/1,
+         otp_14285/1, otp_14378/1]).
 
 suite() ->
     [{ct_hooks,[ts_install_cth]},
@@ -87,7 +88,7 @@ all() ->
      maps, maps_type, maps_parallel_match,
      otp_11851, otp_11879, otp_13230,
      record_errors, otp_11879_cont, non_latin1_module, otp_14323,
-     get_stacktrace, otp_14285, otp_14378].
+     get_stacktrace, stacktrace_syntax, otp_14285, otp_14378].
 
 groups() -> 
     [{unused_vars_warn, [],
@@ -4129,6 +4130,40 @@ get_stacktrace(Config) ->
     run(Config, Ts),
     ok.
 
+stacktrace_syntax(Config) ->
+    Ts = [{guard,
+           <<"t1() ->
+                  try error(foo)
+                  catch _:_:Stk when is_number(Stk) -> ok
+                  end.
+           ">>,
+           [],
+           {errors,[{3,erl_lint,{stacktrace_guard,'Stk'}}],[]}},
+          {bound,
+           <<"t1() ->
+                  Stk = [],
+                  try error(foo)
+                  catch _:_:Stk -> ok
+                  end.
+           ">>,
+           [],
+           {errors,[{4,erl_lint,{stacktrace_bound,'Stk'}}],[]}},
+          {guard_and_bound,
+           <<"t1() ->
+                  Stk = [],
+                  try error(foo)
+                  catch _:_:Stk when is_integer(Stk) -> ok
+                  end.
+           ">>,
+           [],
+           {errors,[{4,erl_lint,{stacktrace_bound,'Stk'}},
+                    {4,erl_lint,{stacktrace_guard,'Stk'}}],[]}}
+         ],
+
+    run(Config, Ts),
+    ok.
+
+
 %% Unicode atoms.
 otp_14285(Config) ->
     %% A small sample of all the errors and warnings in module erl_lint.
diff --git a/lib/stdlib/test/ets_SUITE.erl b/lib/stdlib/test/ets_SUITE.erl
index 05451a83fb..07c8b60cbd 100644
--- a/lib/stdlib/test/ets_SUITE.erl
+++ b/lib/stdlib/test/ets_SUITE.erl
@@ -1682,7 +1682,7 @@ do_random_test() ->
     ets:delete(Set),
     verify_etsmem(EtsMem).
 
-%% Ttest various variants of update_element.
+%% Test various variants of update_element.
 update_element(Config) when is_list(Config) ->
     EtsMem = etsmem(),
     repeat_for_opts(fun update_element_opts/1),
@@ -2283,13 +2283,8 @@ write_concurrency(Config) when is_list(Config) ->
     NoHashMem = ets:info(No7,memory),
     NoHashMem = ets:info(No8,memory),
 
-    case erlang:system_info(smp_support) of
-	true ->
-	    true = YesMem > NoHashMem,
-	    true = YesMem > NoTreeMem;
-	false ->
-	    true = YesMem =:= NoHashMem
-    end,
+    true = YesMem > NoHashMem,
+    true = YesMem > NoTreeMem,
 
     {'EXIT',{badarg,_}} = (catch ets_new(foo,[public,{write_concurrency,foo}])),
     {'EXIT',{badarg,_}} = (catch ets_new(foo,[public,{write_concurrency}])),
@@ -5912,16 +5907,11 @@ add_lists([E1|T1], [E2|T2], Acc) ->
 run_smp_workers(InitF,ExecF,FiniF,Laps) ->
     run_smp_workers(InitF,ExecF,FiniF,Laps, 0).
 run_smp_workers(InitF,ExecF,FiniF,Laps, Exclude) ->
-    case erlang:system_info(smp_support) of
-	true ->
-            case erlang:system_info(schedulers_online) of
-                N when N > Exclude ->
-                    run_workers_do(InitF,ExecF,FiniF,Laps, N - Exclude);
-                _ ->
-                    {skipped, "Too few schedulers online"}
-            end;
-	false ->
-	    {skipped,"No smp support"}
+    case erlang:system_info(schedulers_online) of
+        N when N > Exclude ->
+            run_workers_do(InitF,ExecF,FiniF,Laps, N - Exclude);
+        _ ->
+            {skipped, "Too few schedulers online"}
     end.
 
 run_sched_workers(InitF,ExecF,FiniF,Laps) ->
@@ -6231,11 +6221,9 @@ spawn_monitor_with_pid(Pid, Fun, N) ->
 only_if_smp(Func) ->
     only_if_smp(2, Func).
 only_if_smp(Schedulers, Func) ->
-    case {erlang:system_info(smp_support),
-	  erlang:system_info(schedulers_online)} of
-	{false,_} -> {skip,"No smp support"};
-	{true,N} when N < Schedulers -> {skip,"Too few schedulers online"};
-	{true,_} -> Func()
+    case erlang:system_info(schedulers_online) of
+	N when N < Schedulers -> {skip,"Too few schedulers online"};
+	_ -> Func()
     end.
 
 %% Copy-paste from emulator/test/binary_SUITE.erl
@@ -6381,7 +6369,7 @@ very_big_num(0, Result) ->
     Result.
 
 make_port() ->
-    open_port({spawn, "efile"}, [eof]).
+    hd(erlang:ports()).
 
 make_pid() ->
     spawn_link(fun sleeper/0).
diff --git a/lib/stdlib/test/filelib_SUITE.erl b/lib/stdlib/test/filelib_SUITE.erl
index c94821bc75..930cea347f 100644
--- a/lib/stdlib/test/filelib_SUITE.erl
+++ b/lib/stdlib/test/filelib_SUITE.erl
@@ -33,6 +33,8 @@
 -include_lib("common_test/include/ct.hrl").
 -include_lib("kernel/include/file.hrl").
 
+-define(PRIM_FILE, prim_file).
+
 init_per_testcase(_Case, Config) ->
     Config.
 
@@ -120,7 +122,7 @@ wcc(Wc, Error) ->
 do_wildcard_1(Dir, Wcf0) ->
     do_wildcard_2(Dir, Wcf0),
     Wcf = fun(Wc0) ->
-		  Wc = filename:join(Dir, Wc0),
+		  Wc = Dir ++ "/" ++ Wc0,
 		  L = Wcf0(Wc),
 		  [subtract_dir(N, Dir) || N <- L]
 	  end,
@@ -268,8 +270,37 @@ do_wildcard_9(Dir, Wcf) ->
     %% Cleanup.
     del(Files),
     [ok = file:del_dir(D) || D <- lists:reverse(Dirs)],
-    ok.
+    do_wildcard_10(Dir, Wcf).
+
+%% ERL-451/OTP-14577: Escape characters using \\.
+do_wildcard_10(Dir, Wcf) ->
+    All0 = ["{abc}","abc","def","---","z--","@a,b","@c"],
+    All = case os:type() of
+              {unix,_} ->
+                  %% '?' is allowed in file names on Unix, but
+                  %% not on Windows.
+                  ["?q"|All0];
+              _ ->
+                  All0
+          end,
+    Files = mkfiles(lists:reverse(All), Dir),
 
+    ["{abc}"] = Wcf("\\{a*"),
+    ["{abc}"] = Wcf("\\{abc}"),
+    ["abc","def","z--"] = Wcf("[a-z]*"),
+    ["---","abc","z--"] = Wcf("[a\\-z]*"),
+    ["@a,b","@c"] = Wcf("@{a\\,b,c}"),
+    ["@c"] = Wcf("@{a,b,c}"),
+
+    case os:type() of
+        {unix,_} ->
+            ["?q"] = Wcf("\\?q");
+        _ ->
+            [] = Wcf("\\?q")
+    end,
+
+    del(Files),
+    ok.
 
 fold_files(Config) when is_list(Config) ->
     Dir = filename:join(proplists:get_value(priv_dir, Config), "fold_files"),
@@ -417,10 +448,10 @@ wildcard_symlink(Config) when is_list(Config) ->
 						erl_prim_loader)),
 	    ["sub","symlink"] =
 		basenames(Dir, filelib:wildcard(filename:join(Dir, "*"),
-						prim_file)),
+						?PRIM_FILE)),
 	    ["symlink"] =
 		basenames(Dir, filelib:wildcard(filename:join(Dir, "symlink"),
-						prim_file)),
+						?PRIM_FILE)),
 	    ok = file:delete(AFile),
 	    %% The symlink should still be visible even when its target
 	    %% has been deleted.
@@ -436,10 +467,10 @@ wildcard_symlink(Config) when is_list(Config) ->
 						erl_prim_loader)),
 	    ["sub","symlink"] =
 		basenames(Dir, filelib:wildcard(filename:join(Dir, "*"),
-						prim_file)),
+						?PRIM_FILE)),
 	    ["symlink"] =
 		basenames(Dir, filelib:wildcard(filename:join(Dir, "symlink"),
-						prim_file)),
+						?PRIM_FILE)),
 	    ok
     end.
 
@@ -468,17 +499,17 @@ is_file_symlink(Config) ->
 	ok ->
 	    true = filelib:is_dir(DirAlias),
 	    true = filelib:is_dir(DirAlias, erl_prim_loader),
-	    true = filelib:is_dir(DirAlias, prim_file),
+	    true = filelib:is_dir(DirAlias, ?PRIM_FILE),
 	    true = filelib:is_file(DirAlias),
 	    true = filelib:is_file(DirAlias, erl_prim_loader),
-	    true = filelib:is_file(DirAlias, prim_file),
+	    true = filelib:is_file(DirAlias, ?PRIM_FILE),
 	    ok = file:make_symlink(AFile,FileAlias),
 	    true = filelib:is_file(FileAlias),
 	    true = filelib:is_file(FileAlias, erl_prim_loader),
-	    true = filelib:is_file(FileAlias, prim_file),
+	    true = filelib:is_file(FileAlias, ?PRIM_FILE),
 	    true = filelib:is_regular(FileAlias),
 	    true = filelib:is_regular(FileAlias, erl_prim_loader),
-	    true = filelib:is_regular(FileAlias, prim_file),
+	    true = filelib:is_regular(FileAlias, ?PRIM_FILE),
 	    ok
     end.
 
@@ -499,11 +530,11 @@ file_props_symlink(Config) ->
 	    {_,_} = LastMod = filelib:last_modified(AFile),
 	    LastMod = filelib:last_modified(Alias),
 	    LastMod = filelib:last_modified(Alias, erl_prim_loader),
-	    LastMod = filelib:last_modified(Alias, prim_file),
+	    LastMod = filelib:last_modified(Alias, ?PRIM_FILE),
 	    FileSize = filelib:file_size(AFile),
 	    FileSize = filelib:file_size(Alias),
 	    FileSize = filelib:file_size(Alias, erl_prim_loader),
-	    FileSize = filelib:file_size(Alias, prim_file)
+	    FileSize = filelib:file_size(Alias, ?PRIM_FILE)
     end.
 
 find_source(Config) when is_list(Config) ->
diff --git a/lib/stdlib/test/gen_server_SUITE.erl b/lib/stdlib/test/gen_server_SUITE.erl
index 2e9dc4d4fb..2bc220fef2 100644
--- a/lib/stdlib/test/gen_server_SUITE.erl
+++ b/lib/stdlib/test/gen_server_SUITE.erl
@@ -27,7 +27,7 @@
 -export([all/0, suite/0,groups/0,init_per_suite/1, end_per_suite/1, 
 	 init_per_group/2,end_per_group/2]).
 -export([start/1, crash/1, call/1, cast/1, cast_fast/1,
-	 info/1, abcast/1, multicall/1, multicall_down/1,
+	 continue/1, info/1, abcast/1, multicall/1, multicall_down/1,
 	 call_remote1/1, call_remote2/1, call_remote3/1,
 	 call_remote_n1/1, call_remote_n2/1, call_remote_n3/1, spec_init/1,
 	 spec_init_local_registered_parent/1, 
@@ -37,7 +37,8 @@
 	 get_state/1, replace_state/1, call_with_huge_message_queue/1,
 	 undef_handle_call/1, undef_handle_cast/1, undef_handle_info/1,
 	 undef_init/1, undef_code_change/1, undef_terminate1/1,
-	 undef_terminate2/1, undef_in_terminate/1, undef_in_handle_info/1
+	 undef_terminate2/1, undef_in_terminate/1, undef_in_handle_info/1,
+	 undef_handle_continue/1
 	]).
 
 -export([stop1/1, stop2/1, stop3/1, stop4/1, stop5/1, stop6/1, stop7/1,
@@ -52,7 +53,7 @@
 
 
 %% The gen_server behaviour
--export([init/1, handle_call/3, handle_cast/2,
+-export([init/1, handle_call/3, handle_cast/2, handle_continue/2,
 	 handle_info/2, code_change/3, terminate/2, format_status/2]).
 
 suite() ->
@@ -61,7 +62,7 @@ suite() ->
 
 all() -> 
     [start, {group,stop}, crash, call, cast, cast_fast, info, abcast,
-     multicall, multicall_down, call_remote1, call_remote2,
+     continue, multicall, multicall_down, call_remote1, call_remote2,
      call_remote3, call_remote_n1, call_remote_n2,
      call_remote_n3, spec_init,
      spec_init_local_registered_parent,
@@ -76,7 +77,7 @@ groups() ->
     [{stop, [],
       [stop1, stop2, stop3, stop4, stop5, stop6, stop7, stop8, stop9, stop10]},
      {undef_callbacks, [],
-      [undef_handle_call, undef_handle_cast, undef_handle_info,
+      [undef_handle_call, undef_handle_cast, undef_handle_info, undef_handle_continue,
        undef_init, undef_code_change, undef_terminate1, undef_terminate2]}].
 
 
@@ -458,6 +459,47 @@ call(Config) when is_list(Config) ->
     ok.
 
 %% --------------------------------------
+%% Test handle_continue.
+%% --------------------------------------
+
+continue(Config) when is_list(Config) ->
+    {ok, Pid} = gen_server:start_link(gen_server_SUITE, {continue, self()}, []),
+    [{Pid, continue}, {Pid, after_continue}] = read_replies(Pid),
+
+    gen_server:call(Pid, {continue_reply, self()}),
+    [{Pid, continue}, {Pid, after_continue}] = read_replies(Pid),
+
+    gen_server:call(Pid, {continue_noreply, self()}),
+    [{Pid, continue}, {Pid, after_continue}] = read_replies(Pid),
+
+    gen_server:cast(Pid, {continue_noreply, self()}),
+    [{Pid, continue}, {Pid, after_continue}] = read_replies(Pid),
+
+    Pid ! {continue_noreply, self()},
+    [{Pid, continue}, {Pid, after_continue}] = read_replies(Pid),
+
+    Pid ! {continue_continue, self()},
+    [{Pid, before_continue}, {Pid, continue}, {Pid, after_continue}] = read_replies(Pid),
+
+    Ref = monitor(process, Pid),
+    Pid ! continue_stop,
+    verify_down_reason(Ref, Pid, normal).
+
+read_replies(Pid) ->
+    receive
+	{Pid, ack} -> read_replies()
+    after
+	1000 -> ct:fail({continue, ack})
+    end.
+
+read_replies() ->
+    receive
+	Msg -> [Msg | read_replies()]
+    after
+	0 -> []
+    end.
+
+%% --------------------------------------
 %% Test call to nonexisting processes on remote nodes
 %% --------------------------------------
 
@@ -1346,7 +1388,7 @@ echo_loop() ->
 %% Test the default implementation of terminate if the callback module
 %% does not export it
 undef_terminate1(Config) when is_list(Config) ->
-    {ok, Server} = gen_server:start(oc_server, [], []),
+    {ok, Server} = oc_server:start(),
     MRef = monitor(process, Server),
     ok = gen_server:stop(Server),
     ok = verify_down_reason(MRef, Server, normal).
@@ -1354,7 +1396,7 @@ undef_terminate1(Config) when is_list(Config) ->
 %% Test the default implementation of terminate if the callback module
 %% does not export it
 undef_terminate2(Config) when is_list(Config) ->
-    {ok, Server} = gen_server:start(oc_server, [], []),
+    {ok, Server} = oc_server:start(),
     MRef = monitor(process, Server),
     ok = gen_server:stop(Server, {error, test}, infinity),
     ok = verify_down_reason(MRef, Server, {error, test}).
@@ -1377,7 +1419,7 @@ undef_init(_Config) ->
 %% The upgrade should fail if code_change is expected in the callback module
 %% but not exported, but the server should continue with the old code
 undef_code_change(Config) when is_list(Config) ->
-    {ok, Server} = gen_server:start(oc_server, [], []),
+    {ok, Server} = oc_server:start(),
     {error, {'EXIT', {undef, [{oc_server, code_change, [_, _, _], _}|_]}}}
         = fake_upgrade(Server, ?MODULE),
     true = is_process_alive(Server).
@@ -1385,7 +1427,7 @@ undef_code_change(Config) when is_list(Config) ->
 %% The server should crash if the handle_call callback is
 %% not exported in the callback module
 undef_handle_call(_Config) ->
-    {ok, Server} = gen_server:start(oc_server, [], []),
+    {ok, Server} = oc_server:start(),
     try
         gen_server:call(Server, call_msg),
         ct:fail(should_crash)
@@ -1397,17 +1439,25 @@ undef_handle_call(_Config) ->
 %% The server should crash if the handle_cast callback is
 %% not exported in the callback module
 undef_handle_cast(_Config) ->
-    {ok, Server} = gen_server:start(oc_server, [], []),
+    {ok, Server} = oc_server:start(),
     MRef = monitor(process, Server),
     gen_server:cast(Server, cast_msg),
     verify_undef_down(MRef, Server, oc_server, handle_cast),
     ok.
 
+%% The server should crash if the handle_continue callback is
+%% not exported in the callback module
+undef_handle_continue(_Config) ->
+    {ok, Server} = oc_server:start(continue),
+    MRef = monitor(process, Server),
+    verify_undef_down(MRef, Server, oc_server, handle_continue),
+    ok.
+
 %% The server should log but not crash if the handle_info callback is
 %% calling an undefined function
 undef_handle_info(Config) when is_list(Config) ->
     error_logger_forwarder:register(),
-    {ok, Server} = gen_server:start(oc_server, [], []),
+    {ok, Server} = oc_server:start(),
     Server ! hej,
     wait_until_processed(Server, hej, 10),
     true = is_process_alive(Server),
@@ -1570,8 +1620,11 @@ init(hibernate) ->
 init(sleep) ->
     ct:sleep(1000),
     {ok, []};
+init({continue, Pid}) ->
+    self() ! {after_continue, Pid},
+    {ok, [], {continue, {message, Pid}}};
 init({state,State}) ->
-    {ok, State}.
+    {ok,State}.
 
 handle_call(started_p, _From, State) ->
     io:format("FROZ"),
@@ -1604,6 +1657,12 @@ handle_call(shutdown_reason, _From, _State) ->
 handle_call({call_undef_fun, Mod, Fun}, _From, State) ->
     Mod:Fun(),
     {reply, ok, State};
+handle_call({continue_reply, Pid}, _From, State) ->
+    self() ! {after_continue, Pid},
+    {reply, ok, State, {continue, {message, Pid}}};
+handle_call({continue_noreply, Pid}, From, State) ->
+    self() ! {after_continue, Pid},
+    {noreply, State, {continue, {message, Pid, From}}};
 handle_call(stop_shutdown_reason, _From, State) ->
     {stop,{shutdown,stop_reason},State}.
 
@@ -1620,6 +1679,9 @@ handle_cast(hibernate_later, _State) ->
 handle_cast({call_undef_fun, Mod, Fun}, State) ->
     Mod:Fun(),
     {noreply, State};
+handle_cast({continue_noreply, Pid}, State) ->
+    self() ! {after_continue, Pid},
+    {noreply, State, {continue, {message, Pid}}};
 handle_cast({From, stop}, State) ->
     io:format("BAZ"),
     {stop, {From,stopped}, State}.
@@ -1657,9 +1719,34 @@ handle_info(continue, From) ->
     {noreply, []};
 handle_info({From, stop}, State) ->
     {stop, {From,stopped_info}, State};
+handle_info({after_continue, Pid}, State) ->
+    Pid ! {self(), after_continue},
+    Pid ! {self(), ack},
+    {noreply, State};
+handle_info({continue_noreply, Pid}, State) ->
+    self() ! {after_continue, Pid},
+    {noreply, State, {continue, {message, Pid}}};
+handle_info({continue_continue, Pid}, State) ->
+    {noreply, State, {continue, {continue, Pid}}};
+handle_info(continue_stop, State) ->
+    {noreply, State, {continue, stop}};
 handle_info(_Info, State) ->
     {noreply, State}.
 
+handle_continue({continue, Pid}, State) ->
+    Pid ! {self(), before_continue},
+    self() ! {after_continue, Pid},
+    {noreply, State, {continue, {message, Pid}}};
+handle_continue(stop, State) ->
+    {stop, normal, State};
+handle_continue({message, Pid}, State) ->
+    Pid ! {self(), continue},
+    {noreply, State};
+handle_continue({message, Pid, From}, State) ->
+    Pid ! {self(), continue},
+    gen_server:reply(From, ok),
+    {noreply, State}.
+
 code_change(_OldVsn,
             {new, {undef_in_code_change, {Mod, Fun}}} = State,
             _Extra) ->
diff --git a/lib/stdlib/test/gen_server_SUITE_data/oc_server.erl b/lib/stdlib/test/gen_server_SUITE_data/oc_server.erl
index 4ba37987f3..7b92a49bf6 100644
--- a/lib/stdlib/test/gen_server_SUITE_data/oc_server.erl
+++ b/lib/stdlib/test/gen_server_SUITE_data/oc_server.erl
@@ -22,7 +22,7 @@
 -behaviour(gen_server).
 
 %% API
--export([start/0]).
+-export([start/0, start/1]).
 
 %% gen_server callbacks
 -export([init/1]).
@@ -30,8 +30,12 @@
 -record(state, {}).
 
 start() ->
-    gen_server:start({local, ?MODULE}, ?MODULE, [], []).
+    gen_server:start(?MODULE, ok, []).
 
-init([]) ->
-    {ok, #state{}}.
+start(continue) ->
+    gen_server:start(?MODULE, continue, []).
 
+init(ok) ->
+    {ok, #state{}};
+init(continue) ->
+    {ok, #state{}, {continue, continue}}.
diff --git a/lib/stdlib/test/io_SUITE.erl b/lib/stdlib/test/io_SUITE.erl
index e2c73371cd..13929bdbb6 100644
--- a/lib/stdlib/test/io_SUITE.erl
+++ b/lib/stdlib/test/io_SUITE.erl
@@ -2138,8 +2138,8 @@ otp_14175(_Config) ->
     "#{}" = p(#{}, 1),
     "#{...}" = p(#{a => 1}, 1),
     "#{#{} => a}" = p(#{#{} => a}, 2),
-    "#{a => 1,...}" = p(#{a => 1, b => 2}, 2),
-    "#{a => 1,b => 2}" = p(#{a => 1, b => 2}, -1),
+    mt("#{a => 1,...}", p(#{a => 1, b => 2}, 2)),
+    mt("#{a => 1,b => 2}", p(#{a => 1, b => 2}, -1)),
 
     M = #{kaaaaaaaaaaaaaaaaaaa => v1,kbbbbbbbbbbbbbbbbbbb => v2,
           kccccccccccccccccccc => v3,kddddddddddddddddddd => v4,
diff --git a/lib/stdlib/test/maps_SUITE.erl b/lib/stdlib/test/maps_SUITE.erl
index 42e669a799..a75751b31d 100644
--- a/lib/stdlib/test/maps_SUITE.erl
+++ b/lib/stdlib/test/maps_SUITE.erl
@@ -30,6 +30,7 @@
 -export([t_update_with_3/1, t_update_with_4/1,
          t_get_3/1, t_filter_2/1,
          t_fold_3/1,t_map_2/1,t_size_1/1,
+         t_iterator_1/1,
          t_with_2/1,t_without_2/1]).
 
 %%-define(badmap(V,F,Args), {'EXIT', {{badmap,V}, [{maps,F,Args,_}|_]}}).
@@ -47,6 +48,7 @@ all() ->
     [t_update_with_3,t_update_with_4,
      t_get_3,t_filter_2,
      t_fold_3,t_map_2,t_size_1,
+     t_iterator_1,
      t_with_2,t_without_2].
 
 t_update_with_3(Config) when is_list(Config) ->
@@ -127,6 +129,8 @@ t_filter_2(Config) when is_list(Config) ->
     Pred2 = fun(K,V) -> is_list(K) andalso (V rem 2) =:= 0 end,
     #{a := 2,c := 4} = maps:filter(Pred1,M),
     #{"b" := 2,"c" := 4} = maps:filter(Pred2,M),
+    #{a := 2,c := 4} = maps:filter(Pred1,maps:iterator(M)),
+    #{"b" := 2,"c" := 4} = maps:filter(Pred2,maps:iterator(M)),
     %% error case
     ?badmap(a,filter,[_,a]) = (catch maps:filter(fun(_,_) -> ok end,id(a))),
     ?badarg(filter,[<<>>,#{}]) = (catch maps:filter(id(<<>>),#{})),
@@ -139,6 +143,8 @@ t_fold_3(Config) when is_list(Config) ->
     Tot0 = lists:sum(Vs),
     Tot1 = maps:fold(fun({k,_},V,A) -> A + V end, 0, M0),
     true = Tot0 =:= Tot1,
+    Tot2 = maps:fold(fun({k,_},V,A) -> A + V end, 0, maps:iterator(M0)),
+    true = Tot0 =:= Tot2,
 
     %% error case
     ?badmap(a,fold,[_,0,a]) = (catch maps:fold(fun(_,_,_) -> ok end,0,id(a))),
@@ -151,12 +157,48 @@ t_map_2(Config) when is_list(Config) ->
     #{ {k,1} := 1, {k,200} := 200} = M0,
     M1 = maps:map(fun({k,_},V) -> V + 42 end, M0),
     #{ {k,1} := 43, {k,200} := 242} = M1,
+    M2 = maps:map(fun({k,_},V) -> V + 42 end, maps:iterator(M0)),
+    #{ {k,1} := 43, {k,200} := 242} = M2,
 
     %% error case
     ?badmap(a,map,[_,a]) = (catch maps:map(fun(_,_) -> ok end, id(a))),
     ?badarg(map,[<<>>,#{}]) = (catch maps:map(id(<<>>),#{})),
     ok.
 
+t_iterator_1(Config) when is_list(Config) ->
+
+    %% Small map test
+    M0 = #{ a => 1, b => 2 },
+    I0 = maps:iterator(M0),
+    {K1,V1,I1} = maps:next(I0),
+    {K2,V2,I2} = maps:next(I1),
+    none = maps:next(I2),
+
+    KVList = lists:sort([{K1,V1},{K2,V2}]),
+    KVList = lists:sort(maps:to_list(M0)),
+
+    %% Large map test
+
+    Vs2 = lists:seq(1,200),
+    M2 = maps:from_list([{{k,I},I}||I<-Vs2]),
+    KVList2 = lists:sort(iter_kv(maps:iterator(M2))),
+    KVList2 = lists:sort(maps:to_list(M2)),
+
+    %% Larger map test
+
+    Vs3 = lists:seq(1,10000),
+    M3 = maps:from_list([{{k,I},I}||I<-Vs3]),
+    KVList3 = lists:sort(iter_kv(maps:iterator(M3))),
+    KVList3 = lists:sort(maps:to_list(M3)),
+    ok.
+
+iter_kv(I) ->
+    case maps:next(I) of
+        none ->
+            [];
+        {K,V,NI} ->
+            [{K,V} | iter_kv(NI)]
+    end.
 
 t_size_1(Config) when is_list(Config) ->
       0 = maps:size(#{}),
diff --git a/lib/stdlib/test/property_test/README b/lib/stdlib/test/property_test/README
new file mode 100644
index 0000000000..57602bf719
--- /dev/null
+++ b/lib/stdlib/test/property_test/README
@@ -0,0 +1,12 @@
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%                                                             %%%
+%%%                       WARNING                               %%%
+%%%                                                             %%%
+%%% This is experimental code which may be changed or removed   %%%
+%%%               anytime without any warning.                  %%%
+%%%                                                             %%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+The test in this directory are written assuming that the user has a QuickCheck license.  They are to be run manually.  Some may be possible to be run with other tools, e.g. PropEr.
+
diff --git a/lib/stdlib/test/property_test/uri_string_recompose.erl b/lib/stdlib/test/property_test/uri_string_recompose.erl
new file mode 100644
index 0000000000..e51a671172
--- /dev/null
+++ b/lib/stdlib/test/property_test/uri_string_recompose.erl
@@ -0,0 +1,361 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2008-2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(uri_string_recompose).
+
+-compile(export_all).
+
+-proptest(eqc).
+-proptest([triq,proper]).
+
+-ifndef(EQC).
+-ifndef(PROPER).
+-ifndef(TRIQ).
+-define(EQC,true).
+-endif.
+-endif.
+-endif.
+
+-ifdef(EQC).
+-include_lib("eqc/include/eqc.hrl").
+-define(MOD_eqc,eqc).
+
+-else.
+-ifdef(PROPER).
+-include_lib("proper/include/proper.hrl").
+-define(MOD_eqc,proper).
+
+-else.
+-ifdef(TRIQ).
+-define(MOD_eqc,triq).
+-include_lib("triq/include/triq.hrl").
+
+-endif.
+-endif.
+-endif.
+
+
+-define(STRING_REST(MatchStr, Rest), <<MatchStr/utf8, Rest/binary>>).
+
+-define(SCHEME, {scheme, scheme()}).
+-define(USER, {userinfo, unicode()}).
+-define(HOST, {host, host_map()}).
+-define(PORT, {port, port()}).
+-define(PATH_ABE, {path, path_abempty_map()}).
+-define(PATH_ABS, {path, path_absolute_map()}).
+-define(PATH_NOS, {path, path_noscheme_map()}).
+-define(PATH_ROO, {path, path_rootless_map()}).
+-define(PATH_EMP, {path, path_empty_map()}).
+-define(QUERY, {query, query_map()}).
+-define(FRAGMENT, {fragment, fragment_map()}).
+
+
+%%%========================================================================
+%%% Properties
+%%%========================================================================
+
+prop_recompose() ->
+    ?FORALL(Map, map(),
+            Map =:= uri_string:parse(uri_string:recompose(Map))
+           ).
+
+%% Stats
+prop_map_key_length_collect() ->
+    ?FORALL(List, map(),
+            collect(length(maps:keys(List)), true)).
+
+prop_map_collect() ->
+    ?FORALL(List, map(),
+            collect(lists:sort(maps:keys(List)), true)).
+
+prop_scheme_collect() ->
+    ?FORALL(List, scheme(),
+            collect(length(List), true)).
+
+
+%%%========================================================================
+%%% Generators
+%%%========================================================================
+
+map() ->
+    ?LET(Gen, comp_proplist(), proplist_to_map(Gen)).
+
+comp_proplist() ->
+    frequency([
+               {2, [?SCHEME,?PATH_ABS]},
+               {2, [?SCHEME,?PATH_ROO]},
+               {2, [?SCHEME,?PATH_EMP]},
+               {2, [?SCHEME,?HOST,?PATH_ABE]},
+               {2, [?SCHEME,?USER,?HOST,?PATH_ABE]},
+               {2, [?SCHEME,?HOST,?PORT,?PATH_ABE]},
+               {2, [?SCHEME,?USER,?HOST,?PORT,?PATH_ABE]},
+
+               {2, [?PATH_ABS]},
+               {2, [?PATH_NOS]},
+               {2, [?PATH_EMP]},
+               {2, [?HOST,?PATH_ABE]},
+               {2, [?USER,?HOST,?PATH_ABE]},
+               {2, [?HOST,?PORT,?PATH_ABE]},
+               {2, [?USER,?HOST,?PORT,?PATH_ABE]},
+
+
+               {2, [?SCHEME,?PATH_ABS,?QUERY]},
+               {2, [?SCHEME,?PATH_ROO,?QUERY]},
+               {2, [?SCHEME,?PATH_EMP,?QUERY]},
+               {2, [?SCHEME,?HOST,?PATH_ABE,?QUERY]},
+               {2, [?SCHEME,?USER,?HOST,?PATH_ABE,?QUERY]},
+               {2, [?SCHEME,?HOST,?PORT,?PATH_ABE,?QUERY]},
+               {2, [?SCHEME,?USER,?HOST,?PORT,?PATH_ABE,?QUERY]},
+
+               {2, [?PATH_ABS,?QUERY]},
+               {2, [?PATH_NOS,?QUERY]},
+               {2, [?PATH_EMP,?QUERY]},
+               {2, [?HOST,?PATH_ABE,?QUERY]},
+               {2, [?USER,?HOST,?PATH_ABE,?QUERY]},
+               {2, [?HOST,?PORT,?PATH_ABE,?QUERY]},
+               {2, [?USER,?HOST,?PORT,?PATH_ABE,?QUERY]},
+
+
+               {2, [?SCHEME,?PATH_ABS,?FRAGMENT]},
+               {2, [?SCHEME,?PATH_ROO,?FRAGMENT]},
+               {2, [?SCHEME,?PATH_EMP,?FRAGMENT]},
+               {2, [?SCHEME,?HOST,?PATH_ABE,?FRAGMENT]},
+               {2, [?SCHEME,?USER,?HOST,?PATH_ABE,?FRAGMENT]},
+               {2, [?SCHEME,?HOST,?PORT,?PATH_ABE,?FRAGMENT]},
+               {2, [?SCHEME,?USER,?HOST,?PORT,?PATH_ABE,?FRAGMENT]},
+
+               {2, [?PATH_ABS,?FRAGMENT]},
+               {2, [?PATH_NOS,?FRAGMENT]},
+               {2, [?PATH_EMP,?FRAGMENT]},
+               {2, [?HOST,?PATH_ABE,?FRAGMENT]},
+               {2, [?USER,?HOST,?PATH_ABE,?FRAGMENT]},
+               {2, [?HOST,?PORT,?PATH_ABE,?FRAGMENT]},
+               {2, [?USER,?HOST,?PORT,?PATH_ABE,?FRAGMENT]},
+
+
+               {2, [?SCHEME,?PATH_ABS,?QUERY,?FRAGMENT]},
+               {2, [?SCHEME,?PATH_ROO,?QUERY,?FRAGMENT]},
+               {2, [?SCHEME,?PATH_EMP,?QUERY,?FRAGMENT]},
+               {2, [?SCHEME,?HOST,?PATH_ABE,?QUERY,?FRAGMENT]},
+               {2, [?SCHEME,?USER,?HOST,?PATH_ABE,?QUERY,?FRAGMENT]},
+               {2, [?SCHEME,?HOST,?PORT,?PATH_ABE,?QUERY,?FRAGMENT]},
+               {2, [?SCHEME,?USER,?HOST,?PORT,?PATH_ABE,?QUERY,?FRAGMENT]},
+
+               {2, [?PATH_ABS,?QUERY,?FRAGMENT]},
+               {2, [?PATH_NOS,?QUERY,?FRAGMENT]},
+               {2, [?PATH_EMP,?QUERY,?FRAGMENT]},
+               {2, [?HOST,?PATH_ABE,?QUERY,?FRAGMENT]},
+               {2, [?USER,?HOST,?PATH_ABE,?QUERY,?FRAGMENT]},
+               {2, [?HOST,?PORT,?PATH_ABE,?QUERY,?FRAGMENT]},
+               {2, [?USER,?HOST,?PORT,?PATH_ABE,?QUERY,?FRAGMENT]}
+              ]).
+
+
+%%-------------------------------------------------------------------------
+%% Path
+%%-------------------------------------------------------------------------
+path_abempty_map() ->
+    frequency([{90, path_abe_map()},
+               {10, path_empty_map()}]).
+
+path_abe_map() ->
+    ?SIZED(Length, path_abe_map(Length, [])).
+%%
+path_abe_map(0, Segments) ->
+    ?LET(Gen, Segments, lists:append(Gen));
+path_abe_map(N, Segments) ->
+    path_abe_map(N-1, [slash(),segment()|Segments]).
+
+
+path_absolute_map() ->
+    ?SIZED(Length, path_absolute_map(Length, [])).
+%%
+path_absolute_map(0, Segments) ->
+    ?LET(Gen, [slash(),segment_nz()|Segments], lists:append(Gen));
+path_absolute_map(N, Segments) ->
+    path_absolute_map(N-1, [slash(),segment()|Segments]).
+
+
+path_noscheme_map() ->
+    ?SIZED(Length, path_noscheme_map(Length, [])).
+%%
+path_noscheme_map(0, Segments) ->
+    ?LET(Gen, [segment_nz_nc()|Segments], lists:append(Gen));
+path_noscheme_map(N, Segments) ->
+    path_noscheme_map(N-1, [slash(),segment()|Segments]).
+
+path_rootless_map() ->
+    ?SIZED(Length, path_rootless_map(Length, [])).
+%%
+path_rootless_map(0, Segments) ->
+    ?LET(Gen, [segment_nz()|Segments], lists:append(Gen));
+path_rootless_map(N, Segments) ->
+    path_rootless_map(N-1, [slash(),segment()|Segments]).
+
+
+segment_nz() ->
+    non_empty(segment()).
+
+segment_nz_nc() ->
+    non_empty(list(frequency([{30, unreserved()},
+                              {10, sub_delims()},
+                              {10, unicode_char()},
+                              {5, oneof([$@])}
+                             ]))).
+
+
+segment() ->
+    list(frequency([{30, unreserved()},
+                    {10, sub_delims()},
+                    {10, unicode_char()},
+                    {5, oneof([$:, $@])}
+                   ])).
+
+slash() ->
+    "/".
+
+path_empty_map() ->
+    "".
+
+
+%%-------------------------------------------------------------------------
+%% Path
+%%-------------------------------------------------------------------------
+host_map() ->
+    frequency([{30, reg_name()},
+               {30, ip_address()}
+              ]).
+
+
+reg_name() ->
+    list(frequency([{30, alpha()},
+                              {10, sub_delims()},
+                              {10, unicode_char()}
+                             ])).
+
+ip_address() ->
+    oneof(["127.0.0.1", "::127.0.0.1",
+           "2001:0db8:0000:0000:0000:0000:1428:07ab",
+           "2001:0db8:0000:0000:0000::1428:07ab",
+           "2001:0db8:0:0:0:0:1428:07ab",
+           "2001:0db8:0::0:1428:07ab"]).
+
+%% Generating only reg-names
+host_uri() ->
+    non_empty(list(frequency([{30, unreserved()},
+                              {10, sub_delims()},
+                              {10, pct_encoded()}
+                             ]))).
+
+%%-------------------------------------------------------------------------
+%% Port, Query, Fragment
+%%-------------------------------------------------------------------------
+port() ->
+    frequency([{10, undefined},
+               {10, range(1,65535)}
+              ]).
+
+query_map() ->
+    unicode().
+
+
+query_uri() ->
+    [$?| non_empty(list(frequency([{20, pchar()},
+                                   {5, oneof([$/, $?])} % punctuation
+                                  ])))].
+
+fragment_map() ->
+    unicode().
+
+fragment_uri() ->
+    [$?| non_empty(list(frequency([{20, pchar()},
+                                   {5, oneof([$/, $?])} % punctuation
+                                  ])))].
+
+
+%%-------------------------------------------------------------------------
+%% Scheme
+%%-------------------------------------------------------------------------
+scheme() ->
+    ?SIZED(Length, scheme_start(Length, [])).
+%%
+scheme_start(0, L) ->
+    ?LET(Gen, L, lists:reverse(Gen));
+scheme_start(N, L) ->
+    scheme(N-1,[alpha()|L]).
+
+scheme(0, L) ->
+    ?LET(Gen, L, lists:reverse(Gen));
+scheme(N, L) ->
+    scheme(N-1, [scheme_char()|L]).
+
+
+%%-------------------------------------------------------------------------
+%% Misc
+%%-------------------------------------------------------------------------
+unicode() ->
+    list(frequency([{20, alpha()},                    % alpha
+               {10, digit()},                    % digit
+               {10, unicode_char()}              % unicode
+              ])).
+
+scheme_char() ->
+    frequency([{20, alpha()},                    % alpha
+               {20, digit()},                    % digit
+               {5, oneof([$+, $-, $.])}          % punctuation
+              ]).
+
+sub_delims() ->
+    oneof([$!, $$, $&, $', $(, $),
+           $*, $+, $,,$;, $=]).
+
+pchar() ->
+    frequency([{20, unreserved()},
+               {5, pct_encoded()},
+               {5, sub_delims()},
+               {1, oneof([$:, $@])}              % punctuation
+              ]).
+
+unreserved() ->
+    frequency([{20, alpha()},
+               {5, digit()},
+               {1, oneof([$-, $., $_, $~])}      % punctuation
+              ]).
+
+unicode_char() ->
+    range(913, 1023).
+
+alpha() ->
+    frequency([{20, range($a, $z)},              % letters
+               {20, range($A, $Z)}]).            % letters
+
+digit() ->
+    range($0, $9).                               % numbers
+
+pct_encoded() ->
+    oneof(["%C3%A4", "%C3%A5", "%C3%B6"]).
+
+
+%%%========================================================================
+%%% Helpers
+%%%========================================================================
+proplist_to_map(L) ->
+    lists:foldl(fun({K,V},M) -> M#{K => V};
+                  (_,M) -> M
+               end, #{}, L).
diff --git a/lib/stdlib/test/qlc_SUITE.erl b/lib/stdlib/test/qlc_SUITE.erl
index 949142ec77..8f8a0f6e73 100644
--- a/lib/stdlib/test/qlc_SUITE.erl
+++ b/lib/stdlib/test/qlc_SUITE.erl
@@ -1695,28 +1695,7 @@ sort(Config) when is_list(Config) ->
           [true || I <- lists:seq(1, 50000), not ets:insert(E, {I, I})],
           H = qlc:q([{X,Y} || X <- [a,b], Y <- qlc:sort(ets:table(E))]),
           100000 = length(qlc:e(H)),
-          ets:delete(E)">>,
-
-       begin
-       TmpDir = ?privdir,
-       [<<"TE = process_flag(trap_exit, true),
-           E = ets:new(foo, []),
-           [true || I <- lists:seq(1, 50000), not ets:insert(E, {I, I})],
-           Ports = erlang:ports(),
-           H = qlc:q([{X,Y} || X <- [a,b], 
-                               begin
-                                   [P] = erlang:ports() -- Ports,
-                                   exit(P, port_exit),
-                                   true
-                               end,
-                               Y <- qlc:sort(ets:table(E),
-                                             [{tmpdir,\"">>, 
-                                               TmpDir, <<"\"}])]),
-           {error, qlc, {file_error, _, _}} = (catch qlc:e(H)),
-           receive {'EXIT', _, port_exit} -> ok end,
-           ets:delete(E),
-           process_flag(trap_exit, TE)">>]
-       end
+          ets:delete(E)">>
 
         ],
     run(Config, Ts),
diff --git a/lib/stdlib/test/rand_SUITE.erl b/lib/stdlib/test/rand_SUITE.erl
index 432293b656..3d3241b33d 100644
--- a/lib/stdlib/test/rand_SUITE.erl
+++ b/lib/stdlib/test/rand_SUITE.erl
@@ -29,11 +29,17 @@
 	 basic_stats_uniform_1/1, basic_stats_uniform_2/1,
 	 basic_stats_standard_normal/1,
 	 basic_stats_normal/1,
+         stats_standard_normal_box_muller/1,
+         stats_standard_normal_box_muller_2/1,
+         stats_standard_normal/1,
+         uniform_real_conv/1,
 	 plugin/1, measure/1,
 	 reference_jump_state/1, reference_jump_procdict/1]).
 
 -export([test/0, gen/1]).
 
+-export([uniform_real_gen/1, uniform_gen/2]).
+
 -include_lib("common_test/include/ct.hrl").
 
 -define(LOOP, 1000000).
@@ -46,7 +52,7 @@ all() ->
     [seed, interval_int, interval_float,
      api_eq,
      reference,
-     {group, basic_stats},
+     {group, basic_stats}, uniform_real_conv,
      plugin, measure,
      {group, reference_jump}
     ].
@@ -54,7 +60,10 @@ all() ->
 groups() ->
     [{basic_stats, [parallel],
       [basic_stats_uniform_1, basic_stats_uniform_2,
-       basic_stats_standard_normal]},
+       basic_stats_standard_normal,
+       stats_standard_normal_box_muller,
+       stats_standard_normal_box_muller_2,
+       stats_standard_normal]},
      {reference_jump, [parallel],
       [reference_jump_state, reference_jump_procdict]}].
 
@@ -80,7 +89,7 @@ test() ->
       end, Tests).
 
 algs() ->
-    [exs64, exsplus, exsp, exrop, exs1024, exs1024s].
+    [exrop, exsp, exs1024s, exs64, exsplus, exs1024].
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
@@ -101,7 +110,7 @@ seed_1(Alg) ->
     _ = rand:uniform(),
     S00 = get(rand_seed),
     erase(),
-    _ = rand:uniform(),
+    _ = rand:uniform_real(),
     false = S00 =:= get(rand_seed), %% hopefully
 
     %% Choosing algo and seed
@@ -228,11 +237,13 @@ interval_float(Config) when is_list(Config) ->
 interval_float_1(0) -> ok;
 interval_float_1(N) ->
     X = rand:uniform(),
+    Y = rand:uniform_real(),
     if
-	0.0 =< X, X < 1.0 ->
+	0.0 =< X, X < 1.0, 0.0 < Y, Y < 1.0 ->
 	    ok;
 	true ->
-	    io:format("X=~p 0=<~p<1.0~n", [X,X]),
+	    io:format("X=~p 0.0=<~p<1.0~n", [X,X]),
+	    io:format("Y=~p 0.0<~p<1.0~n", [Y,Y]),
 	    exit({X, rand:export_seed()})
     end,
     interval_float_1(N-1).
@@ -334,7 +345,13 @@ basic_stats_normal(Config) when is_list(Config) ->
       IntendedMeanVariancePairs).
 
 basic_uniform_1(N, S0, Sum, A0) when N > 0 ->
-    {X,S} = rand:uniform_s(S0),
+    {X,S} =
+        case N band 1 of
+            0 ->
+                rand:uniform_s(S0);
+            1 ->
+                rand:uniform_real_s(S0)
+        end,
     I = trunc(X*100),
     A = array:set(I, 1+array:get(I,A0), A0),
     basic_uniform_1(N-1, S, Sum+X, A);
@@ -399,6 +416,337 @@ normal_s(Mean, Variance, State0) when Mean == 0, Variance == 1 ->
 normal_s(Mean, Variance, State0) ->
     rand:normal_s(Mean, Variance, State0).
 
+
+
+-dialyzer({no_improper_lists, stats_standard_normal_box_muller/1}).
+stats_standard_normal_box_muller(Config) when is_list(Config) ->
+    try math:erfc(1.0) of
+        _ ->
+            TwoPi = 2.0 * math:pi(),
+            NormalS =
+                fun
+                    ([S0]) ->
+                        {U1, S1} = rand:uniform_real_s(S0),
+                        R = math:sqrt(-2.0 * math:log(U1)),
+                        {U2, S2} = rand:uniform_s(S1),
+                        T = TwoPi * U2,
+                        Z0 = R * math:cos(T),
+                        Z1 = R * math:sin(T),
+                        {Z0, [S2|Z1]};
+                    ([S|Z]) ->
+                        {Z, [S]}
+                end,
+            State = [rand:seed(exrop)],
+            stats_standard_normal(NormalS, State)
+    catch error:_ ->
+            {skip, "math:erfc/1 not supported"}
+    end.
+
+-dialyzer({no_improper_lists, stats_standard_normal_box_muller_2/1}).
+stats_standard_normal_box_muller_2(Config) when is_list(Config) ->
+    try math:erfc(1.0) of
+        _ ->
+            TwoPi = 2.0 * math:pi(),
+            NormalS =
+                fun
+                    ([S0]) ->
+                        {U0, S1} = rand:uniform_s(S0),
+                        U1 = 1.0 - U0,
+                        R = math:sqrt(-2.0 * math:log(U1)),
+                        {U2, S2} = rand:uniform_s(S1),
+                        T = TwoPi * U2,
+                        Z0 = R * math:cos(T),
+                        Z1 = R * math:sin(T),
+                        {Z0, [S2|Z1]};
+                    ([S|Z]) ->
+                        {Z, [S]}
+                end,
+            State = [rand:seed(exrop)],
+            stats_standard_normal(NormalS, State)
+    catch error:_ ->
+            {skip, "math:erfc/1 not supported"}
+    end.
+
+
+stats_standard_normal(Config) when is_list(Config) ->
+    try math:erfc(1.0) of
+        _ ->
+            stats_standard_normal(
+              fun rand:normal_s/1, rand:seed_s(exrop))
+    catch error:_ ->
+            {skip, "math:erfc/1 not supported"}
+    end.
+%%
+stats_standard_normal(Fun, S) ->
+%%%
+%%% ct config:
+%%% {rand_SUITE, [{stats_standard_normal,[{seconds, 8}, {std_devs, 4.2}]}]}.
+%%%
+    Seconds = ct:get_config({?MODULE, ?FUNCTION_NAME, seconds}, 8),
+    StdDevs =
+        ct:get_config(
+          {?MODULE, ?FUNCTION_NAME, std_devs},
+          4.2), % probability erfc(4.2/sqrt(2)) (1/37465) to fail a bucket
+%%%
+    ct:timetrap({seconds, Seconds + 120}),
+    %% Buckets is chosen to get a range where the the probability to land
+    %% in the top catch-all bucket is not vanishingly low, but with
+    %% these values it is about 1/25 of the probability for the low bucket
+    %% (closest to 0).
+    %%
+    %% Rounds is calculated so the expected value for the low
+    %% bucket will be at least TargetHits.
+    %%
+    InvDelta = 512,
+    Buckets = 4 * InvDelta, % 4 std devs range
+    TargetHits = 1024,
+    Sqrt2 = math:sqrt(2.0),
+    W = InvDelta * Sqrt2,
+    P0 = math:erf(1 / W),
+    Rounds = TargetHits * ceil(1.0 / P0),
+    Histogram = array:new({default, 0}),
+    StopTime = erlang:monotonic_time(second) + Seconds,
+    ct:pal(
+      "Running standard normal test against ~w std devs for ~w seconds...",
+      [StdDevs, Seconds]),
+    {PositiveHistogram, NegativeHistogram, Outlier, TotalRounds} =
+        stats_standard_normal(
+          InvDelta, Buckets, Histogram, Histogram, 0.0,
+          Fun, S, Rounds, StopTime, Rounds, 0),
+    Precision = math:sqrt(TotalRounds * P0) / StdDevs,
+    TopP = math:erfc(Buckets / W),
+    TopPrecision = math:sqrt(TotalRounds * TopP) / StdDevs,
+    OutlierProbability = math:erfc(Outlier / Sqrt2) * TotalRounds,
+    InvOP = 1.0 / OutlierProbability,
+    ct:pal(
+      "Total rounds: ~w, tolerance: 1/~.2f..1/~.2f, "
+      "outlier: ~.2f, probability 1/~.2f.",
+      [TotalRounds, Precision, TopPrecision, Outlier, InvOP]),
+    {TotalRounds, [], []} =
+        {TotalRounds,
+         check_histogram(
+           W, TotalRounds, StdDevs, PositiveHistogram, Buckets),
+         check_histogram(
+           W, TotalRounds, StdDevs, NegativeHistogram, Buckets)},
+    %% If the probability for getting this Outlier is lower than 1/50,
+    %% then this is fishy!
+    true = (1/50 =< OutlierProbability),
+    {comment, {tp, TopPrecision, op, InvOP}}.
+%%
+stats_standard_normal(
+  InvDelta, Buckets, PositiveHistogram, NegativeHistogram, Outlier,
+  Fun, S, 0, StopTime, Rounds, TotalRounds) ->
+    case erlang:monotonic_time(second) of
+        Now when Now < StopTime ->
+            stats_standard_normal(
+              InvDelta, Buckets,
+              PositiveHistogram, NegativeHistogram, Outlier,
+              Fun, S, Rounds, StopTime, Rounds, TotalRounds + Rounds);
+        _ ->
+            {PositiveHistogram, NegativeHistogram,
+             Outlier, TotalRounds + Rounds}
+    end;
+stats_standard_normal(
+  InvDelta, Buckets, PositiveHistogram, NegativeHistogram, Outlier,
+  Fun, S, Count, StopTime, Rounds, TotalRounds) ->
+    case Fun(S) of
+        {X, NewS} when 0.0 =< X ->
+            Bucket = min(Buckets, floor(X * InvDelta)),
+            stats_standard_normal(
+              InvDelta, Buckets,
+              increment_bucket(Bucket, PositiveHistogram),
+              NegativeHistogram, max(Outlier, X),
+              Fun, NewS, Count - 1, StopTime, Rounds, TotalRounds);
+        {MinusX, NewS} ->
+            X = -MinusX,
+            Bucket = min(Buckets, floor(X * InvDelta)),
+            stats_standard_normal(
+              InvDelta, Buckets,
+              PositiveHistogram,
+              increment_bucket(Bucket, NegativeHistogram), max(Outlier, X),
+              Fun, NewS, Count - 1, StopTime, Rounds, TotalRounds)
+    end.
+
+increment_bucket(Bucket, Array) ->
+    array:set(Bucket, array:get(Bucket, Array) + 1, Array).
+
+check_histogram(W, Rounds, StdDevs, Histogram, Buckets) ->
+    %%PrevBucket = 512,
+    %%Bucket = PrevBucket - 1,
+    %%P = 0.5 * math:erfc(PrevBucket / W),
+    TargetP = 0.5 * math:erfc(Buckets / W),
+    P = 0.0,
+    N = 0,
+    check_histogram(
+      W, Rounds, StdDevs, Histogram, TargetP,
+      Buckets, Buckets, P, N).
+%%
+check_histogram(
+  _W, _Rounds, _StdDevs, _Histogram, _TargetP,
+  0, _PrevBucket, _PrevP, _PrevN) ->
+    [];
+check_histogram(
+  W, Rounds, StdDevs, Histogram, TargetP,
+  Bucket, PrevBucket, PrevP, PrevN) ->
+    N = PrevN + array:get(Bucket, Histogram),
+    P = 0.5 * math:erfc(Bucket / W),
+    BucketP = P - PrevP,
+    if
+        TargetP =< BucketP ->
+            check_histogram(
+              W, Rounds, StdDevs, Histogram, TargetP,
+              Bucket - 1, PrevBucket, PrevP, N);
+        true ->
+            Exp = BucketP * Rounds,
+            Var = Rounds * BucketP*(1.0 - BucketP),
+            Threshold = StdDevs * math:sqrt(Var),
+            LowerLimit = floor(Exp - Threshold),
+            UpperLimit = ceil(Exp + Threshold),
+            if
+                N < LowerLimit; UpperLimit < N ->
+                    [#{bucket => {Bucket, PrevBucket}, n => N, exp => Exp,
+                       lower => LowerLimit, upper => UpperLimit} |
+                     check_histogram(
+                       W, Rounds, StdDevs, Histogram, TargetP,
+                       Bucket - 1, Bucket, P, 0)];
+                true ->
+                    check_histogram(
+                      W, Rounds, StdDevs, Histogram, TargetP,
+                      Bucket - 1, Bucket, P, 0)
+            end
+    end.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% White box test of the conversion to float
+
+uniform_real_conv(Config) when is_list(Config) ->
+    [begin
+%%         ct:pal("~13.16.0bx~3.16.0b: ~p~n", [M,E,Gen]),
+         uniform_real_conv_check(M, E, Gen)
+     end || {M, E, Gen} <- uniform_real_conv_data()],
+    uniform_real_scan(0),
+    uniform_real_scan(3).
+
+uniform_real_conv_data() ->
+    [{16#fffffffffffff,  -1, [16#3ffffffffffffff]},
+     {16#fffffffffffff,  -1, [16#3ffffffffffffe0]},
+     {16#ffffffffffffe,  -1, [16#3ffffffffffffdf]},
+     %%
+     {16#0000000000000,  -1, [16#200000000000000]},
+     {16#fffffffffffff,  -2, [16#1ffffffffffffff]},
+     {16#fffffffffffff,  -2, [16#1fffffffffffff0]},
+     {16#ffffffffffffe,  -2, [16#1ffffffffffffef]},
+     %%
+     {16#0000000000000,  -2, [16#100000000000000]},
+     {16#fffffffffffff,  -3, [16#0ffffffffffffff]},
+     {16#fffffffffffff,  -3, [16#0fffffffffffff8]},
+     {16#ffffffffffffe,  -3, [16#0fffffffffffff7]},
+     %%
+     {16#0000000000000,  -3, [16#080000000000000]},
+     {16#fffffffffffff,  -4, [16#07fffffffffffff]},
+     {16#fffffffffffff,  -4, [16#07ffffffffffffc]},
+     {16#ffffffffffffe,  -4, [16#07ffffffffffffb]},
+     %%
+     {16#0000000000000,  -4, [16#040000000000000]},
+     {16#fffffffffffff,  -5, [16#03fffffffffffff,16#3ffffffffffffff]},
+     {16#fffffffffffff,  -5, [16#03ffffffffffffe,16#200000000000000]},
+     {16#ffffffffffffe,  -5, [16#03fffffffffffff,16#1ffffffffffffff]},
+     {16#ffffffffffffe,  -5, [16#03fffffffffffff,16#100000000000000]},
+     %%
+     {16#0000000000001, -56, [16#000000000000007,16#00000000000007f]},
+     {16#0000000000001, -56, [16#000000000000004,16#000000000000040]},
+     {16#0000000000000, -57, [16#000000000000003,16#20000000000001f]},
+     {16#0000000000000, -57, [16#000000000000000,16#200000000000000]},
+     {16#fffffffffffff, -58, [16#000000000000003,16#1ffffffffffffff]},
+     {16#fffffffffffff, -58, [16#000000000000000,16#1fffffffffffff0]},
+     {16#ffffffffffffe, -58, [16#000000000000000,16#1ffffffffffffef]},
+     {16#ffffffffffffe, -58, [16#000000000000000,16#1ffffffffffffe0]},
+     %%
+     {16#0000000000000, -58, [16#000000000000000,16#10000000000000f]},
+     {16#0000000000000, -58, [16#000000000000000,16#100000000000000]},
+     {2#11001100000000000000000000000000000000000011000000011, % 53 bits
+      -1022,
+      [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, % 18 zeros
+       2#1100110000000000000000000000000000000000001 bsl 2, % 43 bits
+       2#1000000011 bsl (56-10+2)]}, % 10 bits
+     {0, -1, % 0.5 after retry
+      [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, % 18 zeros
+       2#111111111111111111111111111111111111111111 bsl 2, % 42 bits - retry
+       16#200000000000003]}]. % 0.5
+
+-define(UNIFORM_REAL_SCAN_PATTERN, (16#19000000000009)). % 53 bits
+-define(UNIFORM_REAL_SCAN_NUMBER, (1021)).
+
+uniform_real_scan_template(K) ->
+    <<0:?UNIFORM_REAL_SCAN_NUMBER,
+      ?UNIFORM_REAL_SCAN_PATTERN:53,K:2,0:1>>.
+
+uniform_real_scan(K) ->
+    Templ = uniform_real_scan_template(K),
+    N = ?UNIFORM_REAL_SCAN_NUMBER,
+    uniform_real_scan(Templ, N, K).
+
+uniform_real_scan(Templ, N, K) when 0 =< N ->
+    <<_:N/bits,T/bits>> = Templ,
+    Data = uniform_real_scan_data(T, K),
+    uniform_real_conv_check(
+      ?UNIFORM_REAL_SCAN_PATTERN, N - 1 - ?UNIFORM_REAL_SCAN_NUMBER, Data),
+    uniform_real_scan(Templ, N - 1, K);
+uniform_real_scan(_, _, _) ->
+    ok.
+
+uniform_real_scan_data(Templ, K) ->
+    case Templ of
+        <<X:56, T/bits>> ->
+            B = rand:bc64(X),
+            [(X bsl 2) bor K |
+             if
+                 53 =< B ->
+                     [];
+                 true ->
+                     uniform_real_scan_data(T, K)
+             end];
+        _ ->
+            <<X:56, _/bits>> = <<Templ/bits, 0:56>>,
+            [(X bsl 2) bor K]
+    end.
+
+uniform_real_conv_check(M, E, Gen) ->
+    <<F/float>> = <<0:1, (E + 16#3ff):11, M:52>>,
+    try uniform_real_gen(Gen) of
+        F -> F;
+        FF ->
+            ct:pal(
+              "~s =/= ~s: ~s~n",
+              [rand:float2str(FF), rand:float2str(F),
+               [["16#",integer_to_list(G,16),$\s]||G<-Gen]]),
+            ct:fail({neq, FF, F})
+    catch
+        Error:Reason ->
+            ct:pal(
+              "~w:~p ~s: ~s~n",
+              [Error, Reason, rand:float2str(F),
+               [["16#",integer_to_list(G,16),$\s]||G<-Gen]]),
+            ct:fail({Error, Reason, F, erlang:get_stacktrace()})
+    end.
+
+
+uniform_real_gen(Gen) ->
+    State = rand_state(Gen),
+    {F, {#{type := rand_SUITE_list},[]}} = rand:uniform_real_s(State),
+    F.
+
+uniform_gen(Range, Gen) ->
+    State = rand_state(Gen),
+    {N, {#{type := rand_SUITE_list},[]}} = rand:uniform_s(Range, State),
+    N.
+
+%% Loaded dice for white box tests
+rand_state(Gen) ->
+    {#{type => rand_SUITE_list, bits => 58, weak_low_bits => 1,
+       next => fun ([H|T]) -> {H, T} end},
+     Gen}.
+
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 %% Test that the user can write algorithms.
@@ -459,213 +807,289 @@ measure(Config) ->
             {skip,{will_not_run_in_scaled_time,Scale}}
     end.
 
+-define(CHECK_UNIFORM_RANGE(Gen, Range, X, St),
+        case (Gen) of
+            {(X), (St)} when is_integer(X), 1 =< (X), (X) =< (Range) ->
+                St
+        end).
+-define(CHECK_UNIFORM(Gen, X, St),
+        case (Gen) of
+            {(X), (St)} when is_float(X), 0.0 =< (X), (X) < 1.0 ->
+                St
+        end).
+-define(CHECK_UNIFORM_NZ(Gen, X, St),
+        case (Gen) of
+            {(X), (St)} when is_float(X), 0.0 < (X), (X) =< 1.0 ->
+                St
+        end).
+-define(CHECK_NORMAL(Gen, X, St),
+        case (Gen) of
+            {(X), (St)} when is_float(X) ->
+                St
+        end).
+
 do_measure(_Config) ->
-    Algos =
+    Algs =
+        algs() ++
         try crypto:strong_rand_bytes(1) of
-            <<_>> -> [crypto64, crypto]
+            <<_>> -> [crypto64, crypto_cache, crypto]
         catch
             error:low_entropy -> [];
             error:undef -> []
-        end ++ algs(),
+        end,
     %%
-    ct:pal("RNG uniform integer performance~n",[]),
-    TMark1 =
+    ct:pal("~nRNG uniform integer range 10000 performance~n",[]),
+    _ =
         measure_1(
-          random,
           fun (_) -> 10000 end,
-          undefined,
-          fun (Range, State) ->
-                  {int, random:uniform_s(Range, State)}
-          end),
+          fun (State, Range, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_UNIFORM_RANGE(
+                               Mod:uniform_s(Range, St0), Range,
+                               X, St1)
+                    end,
+                    State)
+          end,
+          Algs),
+    %%
+    ct:pal("~nRNG uniform integer 32 bit performance~n",[]),
     _ =
-        [measure_1(
-           Algo,
-           fun (_) -> 10000 end,
-           TMark1,
-           fun (Range, State) ->
-                   {int, rand:uniform_s(Range, State)}
-           end) || Algo <- Algos],
+        measure_1(
+          fun (_) -> 1 bsl 32 end,
+          fun (State, Range, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_UNIFORM_RANGE(
+                               Mod:uniform_s(Range, St0), Range,
+                               X, St1)
+                    end,
+                    State)
+          end,
+          Algs),
     %%
     ct:pal("~nRNG uniform integer half range performance~n",[]),
-    HalfRangeFun = fun (State) -> half_range(State) end,
-    TMark2 =
-        measure_1(
-          random,
-          HalfRangeFun,
-          undefined,
-          fun (Range, State) ->
-                  {int, random:uniform_s(Range, State)}
-          end),
     _ =
-        [measure_1(
-           Algo,
-           HalfRangeFun,
-           TMark2,
-           fun (Range, State) ->
-                   {int, rand:uniform_s(Range, State)}
-           end) || Algo <- Algos],
-    %%
-    ct:pal("~nRNG uniform integer half range + 1  performance~n",[]),
-    HalfRangePlus1Fun = fun (State) -> half_range(State) + 1 end,
-    TMark3 =
         measure_1(
-          random,
-          HalfRangePlus1Fun,
-          undefined,
-          fun (Range, State) ->
-                  {int, random:uniform_s(Range, State)}
-          end),
+          fun (State) -> half_range(State) end,
+          fun (State, Range, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_UNIFORM_RANGE(
+                               Mod:uniform_s(Range, St0), Range,
+                               X, St1)
+                    end,
+                    State)
+          end,
+          Algs),
+    %%
+    ct:pal("~nRNG uniform integer half range + 1 performance~n",[]),
     _ =
-        [measure_1(
-           Algo,
-           HalfRangePlus1Fun,
-           TMark3,
-           fun (Range, State) ->
-                   {int, rand:uniform_s(Range, State)}
-           end) || Algo <- Algos],
+        measure_1(
+          fun (State) -> half_range(State) + 1 end,
+          fun (State, Range, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_UNIFORM_RANGE(
+                               Mod:uniform_s(Range, St0), Range,
+                               X, St1)
+                    end,
+                    State)
+          end,
+          Algs),
     %%
     ct:pal("~nRNG uniform integer full range - 1 performance~n",[]),
-    FullRangeMinus1Fun = fun (State) -> (half_range(State) bsl 1) - 1 end,
-    TMark4 =
-        measure_1(
-          random,
-          FullRangeMinus1Fun,
-          undefined,
-          fun (Range, State) ->
-                  {int, random:uniform_s(Range, State)}
-          end),
     _ =
-        [measure_1(
-           Algo,
-           FullRangeMinus1Fun,
-           TMark4,
-           fun (Range, State) ->
-                   {int, rand:uniform_s(Range, State)}
-           end) || Algo <- Algos],
+        measure_1(
+          fun (State) -> (half_range(State) bsl 1) - 1 end,
+          fun (State, Range, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_UNIFORM_RANGE(
+                               Mod:uniform_s(Range, St0), Range,
+                               X, St1)
+                    end,
+                    State)
+          end,
+          Algs),
     %%
     ct:pal("~nRNG uniform integer full range performance~n",[]),
-    FullRangeFun = fun (State) -> half_range(State) bsl 1 end,
-    TMark5 =
-        measure_1(
-          random,
-          FullRangeFun,
-          undefined,
-          fun (Range, State) ->
-                  {int, random:uniform_s(Range, State)}
-          end),
     _ =
-        [measure_1(
-           Algo,
-           FullRangeFun,
-           TMark5,
-           fun (Range, State) ->
-                   {int, rand:uniform_s(Range, State)}
-           end) || Algo <- Algos],
+        measure_1(
+          fun (State) -> half_range(State) bsl 1 end,
+          fun (State, Range, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_UNIFORM_RANGE(
+                               Mod:uniform_s(Range, St0), Range,
+                               X, St1)
+                    end,
+                    State)
+          end,
+          Algs),
     %%
     ct:pal("~nRNG uniform integer full range + 1 performance~n",[]),
-    FullRangePlus1Fun = fun (State) -> (half_range(State) bsl 1) + 1 end,
-    TMark6 =
-        measure_1(
-          random,
-          FullRangePlus1Fun,
-          undefined,
-          fun (Range, State) ->
-                  {int, random:uniform_s(Range, State)}
-          end),
     _ =
-        [measure_1(
-           Algo,
-           FullRangePlus1Fun,
-           TMark6,
-           fun (Range, State) ->
-                   {int, rand:uniform_s(Range, State)}
-           end) || Algo <- Algos],
+        measure_1(
+          fun (State) -> (half_range(State) bsl 1) + 1 end,
+          fun (State, Range, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_UNIFORM_RANGE(
+                               Mod:uniform_s(Range, St0), Range,
+                               X, St1)
+                    end,
+                    State)
+          end,
+          Algs),
     %%
     ct:pal("~nRNG uniform integer double range performance~n",[]),
-    DoubleRangeFun = fun (State) -> half_range(State) bsl 2 end,
-    TMark7 =
-        measure_1(
-          random,
-          DoubleRangeFun,
-          undefined,
-          fun (Range, State) ->
-                  {int, random:uniform_s(Range, State)}
-          end),
     _ =
-        [measure_1(
-           Algo,
-           DoubleRangeFun,
-           TMark7,
-           fun (Range, State) ->
-                   {int, rand:uniform_s(Range, State)}
-           end) || Algo <- Algos],
+        measure_1(
+          fun (State) ->
+                  half_range(State) bsl 2
+          end,
+          fun (State, Range, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_UNIFORM_RANGE(
+                               Mod:uniform_s(Range, St0), Range,
+                               X, St1)
+                    end,
+                    State)
+          end,
+          Algs),
     %%
     ct:pal("~nRNG uniform integer double range + 1  performance~n",[]),
-    DoubleRangePlus1Fun = fun (State) -> (half_range(State) bsl 2) + 1 end,
-    TMark8 =
+    _ =
         measure_1(
-          random,
-          DoubleRangePlus1Fun,
-          undefined,
-          fun (Range, State) ->
-                  {int, random:uniform_s(Range, State)}
-          end),
+          fun (State) ->
+                  (half_range(State) bsl 2) + 1
+          end,
+          fun (State, Range, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_UNIFORM_RANGE(
+                               Mod:uniform_s(Range, St0), Range,
+                               X, St1)
+                    end,
+                    State)
+          end,
+          Algs),
+    %%
+    ct:pal("~nRNG uniform integer 64 bit performance~n",[]),
     _ =
-        [measure_1(
-           Algo,
-           DoubleRangePlus1Fun,
-           TMark8,
-           fun (Range, State) ->
-                   {int, rand:uniform_s(Range, State)}
-           end) || Algo <- Algos],
+        measure_1(
+          fun (_) -> 1 bsl 64 end,
+          fun (State, Range, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_UNIFORM_RANGE(
+                               Mod:uniform_s(Range, St0), Range,
+                               X, St1)
+                    end,
+                    State)
+          end,
+          Algs),
     %%
     ct:pal("~nRNG uniform float performance~n",[]),
-    TMark9 =
+    _ =
         measure_1(
-          random,
           fun (_) -> 0 end,
-          undefined,
-          fun (_, State) ->
-                  {uniform, random:uniform_s(State)}
-          end),
+          fun (State, _, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_UNIFORM(Mod:uniform_s(St0), X, St)
+                    end,
+                    State)
+          end,
+          Algs),
+    %%
+    ct:pal("~nRNG uniform_real float performance~n",[]),
     _ =
-        [measure_1(
-           Algo, 
-           fun (_) -> 0 end,
-           TMark9,
-           fun (_, State) ->
-                   {uniform, rand:uniform_s(State)}
-           end) || Algo <- Algos],
+        measure_1(
+          fun (_) -> 0 end,
+          fun (State, _, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_UNIFORM(Mod:uniform_real_s(St0), X, St)
+                    end,
+                    State)
+          end,
+          Algs),
     %%
     ct:pal("~nRNG normal float performance~n",[]),
-    io:format("~.12w: not implemented (too few bits)~n", [random]),
-    _ = [measure_1(
-           Algo,
-           fun (_) -> 0 end,
-           TMark9,
-           fun (_, State) ->
-                   {normal, rand:normal_s(State)}
-           end) || Algo <- Algos],
+    [TMarkNormalFloat|_] =
+        measure_1(
+          fun (_) -> 0 end,
+          fun (State, _, Mod) ->
+                  measure_loop(
+                    fun (St0) ->
+                            ?CHECK_NORMAL(Mod:normal_s(St0), X, St1)
+                    end,
+                    State)
+          end,
+          Algs),
+    %% Just for fun try an implementation of the Box-Muller
+    %% transformation for creating normal distribution floats
+    %% to compare with our Ziggurat implementation.
+    %% Generates two numbers per call that we add so they
+    %% will not be optimized away.  Hence the benchmark time
+    %% is twice what it should be.
+    TwoPi = 2 * math:pi(),
+    _ =
+        measure_1(
+          fun (_) -> 0 end,
+          fun (State, _, Mod) ->
+                  measure_loop(
+                    fun (State0) ->
+                            {U1, State1} = Mod:uniform_real_s(State0),
+                            {U2, State2} = Mod:uniform_s(State1),
+                            R = math:sqrt(-2.0 * math:log(U1)),
+                            T = TwoPi * U2,
+                            Z0 = R * math:cos(T),
+                            Z1 = R * math:sin(T),
+                            ?CHECK_NORMAL({Z0 + Z1, State2}, X, State3)
+                    end,
+                    State)
+          end,
+          exrop, TMarkNormalFloat),
+    ok.
+
+-define(LOOP_MEASURE, (?LOOP div 5)).
+
+measure_loop(Fun, State) ->
+    measure_loop(Fun, State, ?LOOP_MEASURE).
+%%
+measure_loop(Fun, State, N) when 0 < N ->
+    measure_loop(Fun, Fun(State), N-1);
+measure_loop(_, _, _) ->
     ok.
 
-measure_1(Algo, RangeFun, TMark, Gen) ->
+measure_1(RangeFun, Fun, Algs) ->
+    TMark = measure_1(RangeFun, Fun, hd(Algs), undefined),
+    [TMark] ++
+        [measure_1(RangeFun, Fun, Alg, TMark) || Alg <- tl(Algs)].
+
+measure_1(RangeFun, Fun, Alg, TMark) ->
     Parent = self(),
-    Seed =
-        case Algo of
+    {Mod, State} =
+        case Alg of
             crypto64 ->
-                crypto64_seed();
+                {rand, crypto64_seed()};
+            crypto_cache ->
+                {rand, crypto:rand_seed_alg(crypto_cache)};
             crypto ->
-                crypto:rand_seed_s();
+                {rand, crypto:rand_seed_s()};
             random ->
-                random:seed(os:timestamp()), get(random_seed);
+                {random, random:seed(os:timestamp()), get(random_seed)};
             _ ->
-                rand:seed_s(Algo)
+                {rand, rand:seed_s(Alg)}
         end,
-    Range = RangeFun(Seed),
+    Range = RangeFun(State),
     Pid = spawn_link(
             fun() ->
-                    Fun = fun() -> measure_2(?LOOP, Range, Seed, Gen) end,
-                    {Time, ok} = timer:tc(Fun),
+                    {Time, ok} = timer:tc(fun () -> Fun(State, Range, Mod) end),
                     Percent =
                         case TMark of
                             undefined -> 100;
@@ -673,7 +1097,8 @@ measure_1(Algo, RangeFun, TMark, Gen) ->
                         end,
                     io:format(
                       "~.12w: ~p ns ~p% [16#~.16b]~n",
-                      [Algo, (Time * 1000 + 500) div ?LOOP, Percent, Range]),
+                      [Alg, (Time * 1000 + 500) div ?LOOP_MEASURE,
+                       Percent, Range]),
                     Parent ! {self(), Time},
                     normal
             end),
@@ -681,21 +1106,6 @@ measure_1(Algo, RangeFun, TMark, Gen) ->
 	{Pid, Msg} -> Msg
     end.
 
-measure_2(N, Range, State0, Fun) when N > 0 ->
-    case Fun(Range, State0) of
-	{int, {Random, State}}
-	  when is_integer(Random), Random >= 1, Random =< Range ->
-	    measure_2(N-1, Range, State, Fun);
-	{uniform, {Random, State}}
-          when is_float(Random), 0.0 =< Random, Random < 1.0 ->
-	    measure_2(N-1, Range, State, Fun);
-	{normal, {Random, State}} when is_float(Random) ->
-	    measure_2(N-1, Range, State, Fun);
-	Res ->
-	    exit({error, Res, State0})
-    end;
-measure_2(0, _, _, _) -> ok.
-
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% The jump sequence tests has two parts
 %% for those with the functional API (jump/1)
diff --git a/lib/stdlib/test/stdlib.spec b/lib/stdlib/test/stdlib.spec
index 3768e494b2..91712b8963 100644
--- a/lib/stdlib/test/stdlib.spec
+++ b/lib/stdlib/test/stdlib.spec
@@ -1 +1,2 @@
 {suites,"../stdlib_test",all}.
+{skip_suites,"../stdlib_test",stdlib_bench_SUITE, "bench only"}.
diff --git a/lib/stdlib/test/stdlib_bench.spec b/lib/stdlib/test/stdlib_bench.spec
new file mode 100644
index 0000000000..a5d1e1db80
--- /dev/null
+++ b/lib/stdlib/test/stdlib_bench.spec
@@ -0,0 +1,7 @@
+%% Needed to compile ,unicode_util_SUITE and string_SUITE...
+{cases,"../stdlib_test",unicode_util_SUITE, []}.
+{cases,"../stdlib_test",string_SUITE, []}.
+{skip_suites,"../stdlib_test",unicode_util_SUITE, "bench only"}.
+{skip_suites,"../stdlib_test",string_SUITE, "bench only"}.
+
+{suites,"../stdlib_test",[stdlib_bench_SUITE]}.
diff --git a/lib/stdlib/test/stdlib_bench_SUITE.erl b/lib/stdlib/test/stdlib_bench_SUITE.erl
new file mode 100644
index 0000000000..2a9981bb9e
--- /dev/null
+++ b/lib/stdlib/test/stdlib_bench_SUITE.erl
@@ -0,0 +1,208 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2012-2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+
+%%
+-module(stdlib_bench_SUITE).
+-compile([export_all, nowarn_export_all]).
+-include_lib("common_test/include/ct_event.hrl").
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+suite() -> [{ct_hooks,[{ts_install_cth,[{nodenames,2}]}]}].
+
+
+all() ->
+    [{group,unicode}, {group,base64}].
+
+groups() ->
+    [{unicode,[{repeat,5}],
+      [norm_nfc_list, norm_nfc_deep_l, norm_nfc_binary,
+       string_lexemes_list, string_lexemes_binary
+      ]},
+     {base64,[{repeat,5}],
+      [decode_binary, decode_binary_to_string,
+       decode_list, decode_list_to_string,
+       encode_binary, encode_binary_to_string,
+       encode_list, encode_list_to_string,
+       mime_binary_decode, mime_binary_decode_to_string,
+       mime_list_decode, mime_list_decode_to_string]}].
+
+init_per_group(_GroupName, Config) ->
+    Config.
+
+end_per_group(_GroupName, Config) ->
+    Config.
+
+init_per_suite(Config) ->
+    Config.
+
+end_per_suite(Config) ->
+    Config.
+
+init_per_testcase(_Func, Conf) ->
+    Conf.
+
+end_per_testcase(_Func, _Conf) ->
+    ok.
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+-define(REPEAT_NORM, 5).
+
+norm_nfc_list(Config) ->
+    Bin = norm_data(Config),
+    {_N, Mean, _Stddev, Res} = unicode_util_SUITE:time_count(nfc, list, Bin, ?REPEAT_NORM),
+    report(1000.0*Res / Mean).
+
+norm_nfc_deep_l(Config) ->
+    Bin = norm_data(Config),
+    {_N, Mean, _Stddev, Res} = unicode_util_SUITE:time_count(nfc, deep_l, Bin, ?REPEAT_NORM),
+    report(1000.0*Res / Mean).
+
+norm_nfc_binary(Config) ->
+    Bin = norm_data(Config),
+    {_N, Mean, _Stddev, Res} = unicode_util_SUITE:time_count(nfc, binary, Bin, ?REPEAT_NORM),
+    report(1000.0*Res / Mean).
+
+
+string_lexemes_list(Config) ->
+    %% Use nth_lexeme instead of lexemes to avoid building a result of
+    %% large lists which causes large differences between test runs, gc?
+    Bin = norm_data(Config),
+    Fun = fun(Str) -> string:nth_lexeme(Str, 200000, [$;,$\n,$\r]), 200000 end,
+    {_N, Mean, _Stddev, Res} = string_SUITE:time_func(Fun, list, Bin, 15),
+    report(1000.0*Res / Mean).
+
+string_lexemes_binary(Config) ->
+    %% Use nth_lexeme instead of lexemes to avoid building a result of
+    %% large lists which causes large differences between test runs, gc?
+    Bin = norm_data(Config),
+    Fun = fun(Str) -> string:nth_lexeme(Str, 200000, [$;,$\n,$\r]), 200000 end,
+    {_N, Mean, _Stddev, Res} = string_SUITE:time_func(Fun, binary, Bin, ?REPEAT_NORM),
+    report(1000.0*Res / Mean).
+
+%%%
+report(Tps) ->
+    ct_event:notify(#event{name = benchmark_data,
+                           data = [{suite,"stdlib_unicode"},{value,round(Tps)}]}),
+    Tps.
+
+norm_data(Config) ->
+    DataDir0 = proplists:get_value(data_dir, Config),
+    DataDir = filename:join(lists:droplast(filename:split(DataDir0))),
+    File = filename:join([DataDir,"unicode_util_SUITE_data","NormalizationTest.txt"]),
+    {ok, Bin} = file:read_file(File),
+    Bin.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+decode_binary(_Config) ->
+    test(decode, encoded_binary()).
+
+decode_binary_to_string(_Config) ->
+    test(decode_to_string, encoded_binary()).
+
+decode_list(_Config) ->
+    test(decode, encoded_list()).
+
+decode_list_to_string(_Config) ->
+    test(decode_to_string, encoded_list()).
+
+encode_binary(_Config) ->
+    test(encode, binary()).
+
+encode_binary_to_string(_Config) ->
+    test(encode_to_string, binary()).
+
+encode_list(_Config) ->
+    test(encode, list()).
+
+encode_list_to_string(_Config) ->
+    test(encode_to_string, list()).
+
+mime_binary_decode(_Config) ->
+    test(mime_decode, encoded_binary()).
+
+mime_binary_decode_to_string(_Config) ->
+    test(mime_decode_to_string, encoded_binary()).
+
+mime_list_decode(_Config) ->
+    test(mime_decode, encoded_list()).
+
+mime_list_decode_to_string(_Config) ->
+    test(mime_decode_to_string, encoded_list()).
+
+-define(SIZE, 10000).
+-define(N, 1000).
+
+encoded_binary() ->
+    list_to_binary(encoded_list()).
+
+encoded_list() ->
+    L = random_byte_list(round(?SIZE*0.75)),
+    base64:encode_to_string(L).
+
+binary() ->
+    list_to_binary(list()).
+
+list() ->
+    random_byte_list(?SIZE).
+
+test(Func, Data) ->
+    F = fun() -> loop(?N, Func, Data) end,
+    {Time, ok} = timer:tc(fun() -> lspawn(F) end),
+    report_base64(Time).
+
+loop(0, _F, _D) -> garbage_collect(), ok;
+loop(N, F, D) ->
+    _ = base64:F(D),
+    loop(N - 1, F, D).
+
+lspawn(Fun) ->
+    {Pid, Ref} = spawn_monitor(fun() -> exit(Fun()) end),
+    receive
+        {'DOWN', Ref, process, Pid, Rep} -> Rep
+    end.
+
+report_base64(Time) ->
+    Tps = round((?N*1000000)/Time),
+    ct_event:notify(#event{name = benchmark_data,
+                           data = [{suite, "stdlib_base64"},
+                                   {value, Tps}]}),
+    Tps.
+
+%% Copied from base64_SUITE.erl.
+
+random_byte_list(N) ->
+    random_byte_list(N, []).
+
+random_byte_list(0, Acc) ->
+    Acc;
+random_byte_list(N, Acc) ->
+    random_byte_list(N-1, [rand:uniform(255)|Acc]).
+
+make_big_binary(N) ->
+    list_to_binary(mbb(N, [])).
+
+mbb(N, Acc) when N > 256 ->
+    B = list_to_binary(lists:seq(0, 255)),
+    mbb(N - 256, [B | Acc]);
+mbb(N, Acc) ->
+    B = list_to_binary(lists:seq(0, N-1)),
+    lists:reverse(Acc, B).
diff --git a/lib/stdlib/test/string_SUITE.erl b/lib/stdlib/test/string_SUITE.erl
index f43bfb4482..d02a6eac0a 100644
--- a/lib/stdlib/test/string_SUITE.erl
+++ b/lib/stdlib/test/string_SUITE.erl
@@ -47,7 +47,8 @@
 -export([to_upper_to_lower/1]).
 
 %% Run tests when debugging them
--export([debug/0]).
+-export([debug/0, time_func/4]).
+-compile([nowarn_deprecated_function]).
 
 suite() ->
     [{ct_hooks,[ts_install_cth]},
@@ -748,12 +749,12 @@ do_measure(DataDir) ->
     {ok, Bin} = file:read_file(File),
     io:format("~p~n",[byte_size(Bin)]),
     Do = fun(Name, Func, Mode) ->
-                 {N, Mean, Stddev, _} = time_func(Func, Mode, Bin),
+                 {N, Mean, Stddev, _} = time_func(Func, Mode, Bin, 20),
                  io:format("~15w ~6w ~6.2fms ±~5.2fms #~.2w gc included~n",
                            [Name, Mode, Mean/1000, Stddev/1000, N])
          end,
     Do2 = fun(Name, Func, Mode) ->
-                  {N, Mean, Stddev, _} = time_func(Func, binary, <<>>),
+                  {N, Mean, Stddev, _} = time_func(Func, binary, <<>>, 20),
                   io:format("~15w ~6w ~6.2fms ±~5.2fms #~.2w gc included~n",
                             [Name, Mode, Mean/1000, Stddev/1000, N])
           end,
@@ -1029,19 +1030,19 @@ needs_check(_) -> true.
 
 %%%% Timer stuff
 
-time_func(Fun, Mode, Bin) ->
+time_func(Fun, Mode, Bin, Repeat) ->
     timer:sleep(100), %% Let emulator catch up and clean things before test runs
     Self = self(),
     Pid = spawn_link(fun() ->
                              Str = mode(Mode, Bin),
-                             Self ! {self(),time_func(0,0,0, Fun, Str, undefined)}
+                             Self ! {self(),time_func(0,0,0, Fun, Str, undefined, Repeat)}
                      end),
     receive {Pid,Msg} -> Msg end.
 
-time_func(N,Sum,SumSq, Fun, Str, _) when N < 20 ->
+time_func(N,Sum,SumSq, Fun, Str, _, Repeat) when N < Repeat ->
     {Time, Res} = timer:tc(fun() -> Fun(Str) end),
-    time_func(N+1,Sum+Time,SumSq+Time*Time, Fun, Str, Res);
-time_func(N,Sum,SumSq, _, _, Res) ->
+    time_func(N+1,Sum+Time,SumSq+Time*Time, Fun, Str, Res, Repeat);
+time_func(N,Sum,SumSq, _, _, Res, _) ->
     Mean = round(Sum / N),
     Stdev = round(math:sqrt((SumSq - (Sum*Sum/N))/(N - 1))),
     {N, Mean, Stdev, Res}.
diff --git a/lib/stdlib/test/supervisor_1.erl b/lib/stdlib/test/supervisor_1.erl
index 419026749b..c3ccacc587 100644
--- a/lib/stdlib/test/supervisor_1.erl
+++ b/lib/stdlib/test/supervisor_1.erl
@@ -42,6 +42,8 @@ start_child(error) ->
 	set -> gen_server:start_link(?MODULE, error, [])
     end;
 
+start_child({return, Term}) ->
+    Term;
 
 start_child(Extra) ->
     {ok, Pid} = gen_server:start_link(?MODULE, normal, []),
diff --git a/lib/stdlib/test/supervisor_SUITE.erl b/lib/stdlib/test/supervisor_SUITE.erl
index cd2c6b0cbb..761df8eb40 100644
--- a/lib/stdlib/test/supervisor_SUITE.erl
+++ b/lib/stdlib/test/supervisor_SUITE.erl
@@ -39,6 +39,9 @@
 	  sup_start_ignore_temporary_child_start_child_simple/1,
           sup_start_ignore_permanent_child_start_child_simple/1,
 	  sup_start_error_return/1, sup_start_fail/1,
+          sup_start_child_returns_error/1,
+          sup_start_restart_child_returns_error/1,
+          sup_start_child_returns_error_simple/1,
 	  sup_start_map/1, sup_start_map_simple/1,
 	  sup_start_map_faulty_specs/1,
 	  sup_stop_infinity/1, sup_stop_timeout/1, sup_stop_brutal_kill/1,
@@ -65,14 +68,16 @@
 	  simple_one_for_one_extra/1, simple_one_for_one_shutdown/1]).
 
 %% Misc tests
--export([child_unlink/1, tree/1, count_children/1,
+-export([child_unlink/1, tree/1, count_children/1, count_children_supervisor/1,
 	 count_restarting_children/1, get_callback_module/1,
 	 do_not_save_start_parameters_for_temporary_children/1,
 	 do_not_save_child_specs_for_temporary_children/1,
 	 simple_one_for_one_scale_many_temporary_children/1,
          simple_global_supervisor/1, hanging_restart_loop/1,
+	 hanging_restart_loop_rest_for_one/1,
 	 hanging_restart_loop_simple/1, code_change/1, code_change_map/1,
-	 code_change_simple/1, code_change_simple_map/1]).
+	 code_change_simple/1, code_change_simple_map/1,
+         order_of_children/1, scale_start_stop_many_children/1]).
 
 %%-------------------------------------------------------------------------
 
@@ -91,12 +96,15 @@ all() ->
      {group, normal_termination},
      {group, shutdown_termination},
      {group, abnormal_termination}, child_unlink, tree,
-     count_children, count_restarting_children, get_callback_module,
+     count_children, count_children_supervisor, count_restarting_children,
+     get_callback_module,
      do_not_save_start_parameters_for_temporary_children,
      do_not_save_child_specs_for_temporary_children,
      simple_one_for_one_scale_many_temporary_children, temporary_bystander,
-     simple_global_supervisor, hanging_restart_loop, hanging_restart_loop_simple,
-     code_change, code_change_map, code_change_simple, code_change_simple_map].
+     simple_global_supervisor, hanging_restart_loop,
+     hanging_restart_loop_rest_for_one, hanging_restart_loop_simple,
+     code_change, code_change_map, code_change_simple, code_change_simple_map,
+     order_of_children, scale_start_stop_many_children].
 
 groups() -> 
     [{sup_start, [],
@@ -105,7 +113,10 @@ groups() ->
        sup_start_ignore_temporary_child_start_child,
        sup_start_ignore_temporary_child_start_child_simple,
        sup_start_ignore_permanent_child_start_child_simple,
-       sup_start_error_return, sup_start_fail]},
+       sup_start_error_return, sup_start_fail,
+       sup_start_child_returns_error, sup_start_restart_child_returns_error,
+       sup_start_child_returns_error_simple
+      ]},
      {sup_start_map, [],
       [sup_start_map, sup_start_map_simple, sup_start_map_faulty_specs]},
      {sup_stop, [],
@@ -147,6 +158,15 @@ init_per_testcase(_Case, Config) ->
     Config.
 
 end_per_testcase(_Case, _Config) ->
+    %% Clean up to avoid unnecessary error reports in the shell
+    case whereis(sup_test) of
+        SupPid when is_pid(SupPid) ->
+            unlink(SupPid),
+            exit(SupPid,shutdown),
+            ok;
+        _ ->
+            error
+    end,
     ok.
 
 start_link(InitResult) ->
@@ -274,6 +294,7 @@ sup_start_ignore_permanent_child_start_child_simple(Config)
     %% Regression test: check that the supervisor terminates without error.
     exit(Pid, shutdown),
     check_exit_reason(Pid, shutdown).
+
 %%-------------------------------------------------------------------------
 %% Tests what happens if init-callback returns a invalid value.
 sup_start_error_return(Config) when is_list(Config) ->
@@ -289,6 +310,53 @@ sup_start_fail(Config) when is_list(Config) ->
     check_exit_reason(Term).
 
 %%-------------------------------------------------------------------------
+%% Test what happens when the start function for a child returns
+%% {error,Reason} or some other term().
+sup_start_restart_child_returns_error(_Config) ->
+    process_flag(trap_exit, true),
+    Child = {child1, {supervisor_1, start_child, [error]},
+              permanent, 1000, worker, []},
+    {ok, _Pid}  = start_link({ok, {{one_for_one, 2, 3600}, [Child]}}),
+
+    ok = supervisor:terminate_child(sup_test, child1),
+    {error,{function_clause,_}} = supervisor:restart_child(sup_test,child1),
+
+    [{child1,undefined,worker,[]}] = supervisor:which_children(sup_test),
+    ok.
+
+%%-------------------------------------------------------------------------
+%% Test what happens when the start function for a child returns
+%% {error,Reason} or some other term().
+sup_start_child_returns_error(_Config) ->
+    process_flag(trap_exit, true),
+    Child1 = {child1, {supervisor_1, start_child, [{return,{error,reason}}]},
+              permanent, 1000, worker, []},
+    Child2 = {child2, {supervisor_1, start_child, [{return,error_reason}]},
+              permanent, 1000, worker, []},
+    {ok, _Pid}  = start_link({ok, {{one_for_one, 2, 3600}, []}}),
+
+    {error,{reason,_}} = supervisor:start_child(sup_test,Child1),
+    {error,{error_reason,_}} = supervisor:start_child(sup_test,Child2),
+
+    [] = supervisor:which_children(sup_test),
+    ok.
+
+%%-------------------------------------------------------------------------
+%% Test what happens when the start function for a child returns
+%% {error,Reason} - simple_one_for_one
+sup_start_child_returns_error_simple(_Config) ->
+    process_flag(trap_exit, true),
+    Child = {child1, {supervisor_1, start_child, []},
+             permanent, 1000, worker, []},
+    {ok, _Pid}  = start_link({ok, {{simple_one_for_one, 2, 3600}, [Child]}}),
+
+    {error,reason} = supervisor:start_child(sup_test,[{return,{error,reason}}]),
+    {error,error_reason} = supervisor:start_child(sup_test,[{return,error_reason}]),
+
+    [] = supervisor:which_children(sup_test),
+    ok.
+
+%%-------------------------------------------------------------------------
 %% Tests that the supervisor process starts correctly with map
 %% startspec, and that the full childspec can be read.
 sup_start_map(Config) when is_list(Config) ->
@@ -468,7 +536,16 @@ extra_return(Config) when is_list(Config) ->
     [{child1, CPid3, worker, []}] = supervisor:which_children(sup_test),
     [1,1,0,1] = get_child_counts(sup_test),
 
-    ok.
+    %% Check that it can be automatically restarted
+    terminate(CPid3, abnormal),
+    [{child1, CPid4, worker, []}] = supervisor:which_children(sup_test),
+    [1,1,0,1] = get_child_counts(sup_test),
+    if (not is_pid(CPid4)) orelse CPid4=:=CPid3 ->
+            ct:fail({not_restarted,CPid3,CPid4});
+       true ->
+            ok
+    end.
+
 %%-------------------------------------------------------------------------
 %% Test API functions start_child/2, terminate_child/2, delete_child/2
 %% restart_child/2, which_children/1, count_children/1. Only correct
@@ -1140,7 +1217,7 @@ simple_one_for_one(Config) when is_list(Config) ->
     [{Id4, Pid4, _, _}|_] = supervisor:which_children(sup_test),
 
     terminate(SupPid, Pid4, Id4, abnormal),
-    check_exit([SupPid]).
+    check_exit_reason(SupPid,shutdown).
 
 
 %%-------------------------------------------------------------------------
@@ -1378,6 +1455,11 @@ tree(Config) when is_list(Config) ->
 		  [?MODULE, {ok, {{one_for_one, 4, 3600}, []}}]},
 		 permanent, infinity,
 		 supervisor, []},
+    ChildSup3 = {supchild3,
+		 {supervisor, start_link,
+		  [?MODULE, {ok, {{one_for_one, 4, 3600}, []}}]},
+		 transient, infinity,
+		 supervisor, []},
 
     %% Top supervisor
     {ok, SupPid} = start_link({ok, {{one_for_all, 4, 3600}, []}}),
@@ -1385,7 +1467,9 @@ tree(Config) when is_list(Config) ->
     %% Child supervisors  
     {ok, Sup1} = supervisor:start_child(SupPid, ChildSup1),
     {ok, Sup2} = supervisor:start_child(SupPid, ChildSup2),
-    [2,2,2,0] = get_child_counts(SupPid),
+    {ok, _Sup3} = supervisor:start_child(SupPid, ChildSup3),
+    ok = supervisor:terminate_child(SupPid, supchild3),
+    [3,2,3,0] = get_child_counts(SupPid),
 
     %% Workers
     [{_, CPid2, _, _},{_, CPid1, _, _}] =
@@ -1417,16 +1501,21 @@ tree(Config) when is_list(Config) ->
 
     timer:sleep(1000),
 
-    [{supchild2, NewSup2, _, _},{supchild1, NewSup1, _, _}] =
+    [{supchild3, NewSup3, _, _},
+     {supchild2, NewSup2, _, _},
+     {supchild1, NewSup1, _, _}] =
 	supervisor:which_children(SupPid),
-    [2,2,2,0] = get_child_counts(SupPid),
+    [3,3,3,0] = get_child_counts(SupPid),
 
     [{child2, _, _, _},{child1, _, _, _}]  =
 	supervisor:which_children(NewSup1),
     [2,2,0,2] = get_child_counts(NewSup1),
 
     [] = supervisor:which_children(NewSup2),
-    [0,0,0,0] = get_child_counts(NewSup2).
+    [0,0,0,0] = get_child_counts(NewSup2),
+
+    [] = supervisor:which_children(NewSup3),
+    [0,0,0,0] = get_child_counts(NewSup3).
 
 %%-------------------------------------------------------------------------
 %% Test count_children
@@ -1459,6 +1548,36 @@ count_children(Config) when is_list(Config) ->
     [1,0,0,0] = get_child_counts(sup_test).
 
 %%-------------------------------------------------------------------------
+%% Test count_children for simple_one_for_one, when children are supervisors
+count_children_supervisor(Config) when is_list(Config) ->
+    process_flag(trap_exit, true),
+    Child = {child, {supervisor_1, start_child, []}, temporary, infinity,
+	     supervisor, []},
+    {ok, SupPid} = start_link({ok, {{simple_one_for_one, 2, 3600}, [Child]}}),
+    [supervisor:start_child(sup_test, []) || _Ignore <- lists:seq(1,1000)],
+
+    Children = supervisor:which_children(sup_test),
+    ChildCount = get_child_counts(sup_test),
+
+    [supervisor:start_child(sup_test, []) || _Ignore2 <- lists:seq(1,1000)],
+
+    ChildCount2 = get_child_counts(sup_test),
+    Children2 = supervisor:which_children(sup_test),
+
+    ChildCount3 = get_child_counts(sup_test),
+    Children3 = supervisor:which_children(sup_test),
+
+    1000 = length(Children),
+    [1,1000,1000,0] = ChildCount,
+    2000 = length(Children2),
+    [1,2000,2000,0] = ChildCount2,
+    Children3 = Children2,
+    ChildCount3 = ChildCount2,
+
+    [terminate(SupPid, Pid, child, kill) || {undefined, Pid, supervisor, _Modules} <- Children3],
+    [1,0,0,0] = get_child_counts(sup_test).
+
+%%-------------------------------------------------------------------------
 %% Test count_children when some children are restarting
 count_restarting_children(Config) when is_list(Config) ->
     process_flag(trap_exit, true),
@@ -1577,11 +1696,11 @@ dont_save_start_parameters_for_temporary_children(simple_one_for_one = Type) ->
     start_children(Sup2, [LargeList], 100),
     start_children(Sup3, [LargeList], 100),
 
-    [{memory,Mem1}] = process_info(Sup1, [memory]),
-    [{memory,Mem2}] = process_info(Sup2, [memory]),
-    [{memory,Mem3}] = process_info(Sup3, [memory]),
+    Size1 = erts_debug:flat_size(sys:get_status(Sup1)),
+    Size2 = erts_debug:flat_size(sys:get_status(Sup2)),
+    Size3 = erts_debug:flat_size(sys:get_status(Sup3)),
 
-    true = (Mem3 < Mem1)  and  (Mem3 < Mem2),
+    true = (Size3 < Size1)  and  (Size3 < Size2),
 
     terminate(Sup1, shutdown),
     terminate(Sup2, shutdown),
@@ -1605,11 +1724,11 @@ dont_save_start_parameters_for_temporary_children(Type) ->
     start_children(Sup2, Transient, 100),
     start_children(Sup3, Temporary, 100),
 
-    [{memory,Mem1}] = process_info(Sup1, [memory]),
-    [{memory,Mem2}] = process_info(Sup2, [memory]),
-    [{memory,Mem3}] = process_info(Sup3, [memory]),
+    Size1 = erts_debug:flat_size(sys:get_status(Sup1)),
+    Size2 = erts_debug:flat_size(sys:get_status(Sup2)),
+    Size3 = erts_debug:flat_size(sys:get_status(Sup3)),
 
-    true = (Mem3 < Mem1)  and  (Mem3 < Mem2),
+    true = (Size3 < Size1)  and  (Size3 < Size2),
 
     terminate(Sup1, shutdown),
     terminate(Sup2, shutdown),
@@ -1847,6 +1966,61 @@ hanging_restart_loop(Config) when is_list(Config) ->
     undefined = whereis(sup_test),
     ok.
 
+hanging_restart_loop_rest_for_one(Config) when is_list(Config) ->
+    process_flag(trap_exit, true),
+    {ok, Pid} = start_link({ok, {{rest_for_one, 8, 10}, []}}),
+    Child1 = {child1, {supervisor_1, start_child, []},
+	      permanent, brutal_kill, worker, []},
+    Child2 = {child2, {supervisor_deadlock, start_child, []},
+	      permanent, brutal_kill, worker, []},
+    Child3 = {child3, {supervisor_1, start_child, []},
+	      permanent, brutal_kill, worker, []},
+
+    %% Ets table with state read by supervisor_deadlock.erl
+    ets:new(supervisor_deadlock,[set,named_table,public]),
+    ets:insert(supervisor_deadlock,{fail_start,false}),
+
+    {ok, CPid1} = supervisor:start_child(sup_test, Child1),
+    {ok, CPid2} = supervisor:start_child(sup_test, Child2),
+    link(CPid2),
+    {ok, _CPid3} = supervisor:start_child(sup_test, Child3),
+
+    ets:insert(supervisor_deadlock,{fail_start,true}),
+    supervisor_deadlock:restart_child(),
+    timer:sleep(2000), % allow restart to happen before proceeding
+
+    {error, already_present} = supervisor:start_child(sup_test, Child2),
+    {error, restarting} = supervisor:restart_child(sup_test, child2),
+    {error, restarting} = supervisor:delete_child(sup_test, child2),
+    [{child3,undefined,worker,[]},
+     {child2,restarting,worker,[]},
+     {child1,CPid1,worker,[]}] = supervisor:which_children(sup_test),
+    [3,1,0,3] = get_child_counts(sup_test),
+
+    ok = supervisor:terminate_child(sup_test, child2),
+    check_exit_reason(CPid2, error),
+    [{child3,undefined,worker,[]},
+     {child2,undefined,worker,[]},
+     {child1,CPid1,worker,[]}] = supervisor:which_children(sup_test),
+
+    ets:insert(supervisor_deadlock,{fail_start,false}),
+    {ok, CPid22} = supervisor:restart_child(sup_test, child2),
+    link(CPid22),
+
+    ets:insert(supervisor_deadlock,{fail_start,true}),
+    supervisor_deadlock:restart_child(),
+    timer:sleep(2000), % allow restart to happen before proceeding
+
+    %% Terminating supervisor.
+    %% OTP-9549 fixes so this does not give a timetrap timeout -
+    %% i.e. that supervisor does not hang in restart loop.
+    terminate(Pid,shutdown),
+
+    %% Check that child died with reason from 'restart' request above
+    check_exit_reason(CPid22, error),
+    undefined = whereis(sup_test),
+    ok.
+
 %%-------------------------------------------------------------------------
 %% Test that child and supervisor can be shutdown while hanging in
 %% restart loop, simple_one_for_one.
@@ -2022,11 +2196,11 @@ code_change_simple(_Config) ->
     SimpleChild2 = {child2,{supervisor_1, start_child, []}, permanent,
 		    brutal_kill, worker, []},
 
-    {error, {error, {ok,[_,_]}}} =
+    {error, {error, {ok,{[_,_],_}}}} =
 	fake_upgrade(SimplePid,{ok,{SimpleFlags,[SimpleChild1,SimpleChild2]}}),
 
     %% Attempt to remove child
-    {error, {error, {ok,[]}}} = fake_upgrade(SimplePid,{ok,{SimpleFlags,[]}}),
+    {error, {error, {ok,{[],_}}}} = fake_upgrade(SimplePid,{ok,{SimpleFlags,[]}}),
 
     terminate(SimplePid,shutdown),
     ok.
@@ -2047,11 +2221,11 @@ code_change_simple_map(_Config) ->
     %% Attempt to add child
     SimpleChild2 = #{id=>child2,
 		     start=>{supervisor_1, start_child, []}},
-    {error, {error, {ok, [_,_]}}} =
+    {error, {error, {ok, {[_,_],_}}}} =
 	fake_upgrade(SimplePid,{ok,{SimpleFlags,[SimpleChild1,SimpleChild2]}}),
 
     %% Attempt to remove child
-    {error, {error, {ok, []}}} =
+    {error, {error, {ok, {[],_}}}} =
 	fake_upgrade(SimplePid,{ok,{SimpleFlags,[]}}),
 
     terminate(SimplePid,shutdown),
@@ -2075,6 +2249,148 @@ fake_upgrade(Pid,NewInitReturn) ->
     ok = sys:resume(Pid),
     R.
 
+%% Test that children are started in the order they are given, and
+%% terminated in the opposite order
+order_of_children(_Config) ->
+    process_flag(trap_exit, true),
+    %% Use child ids that are not alphabetically storted
+    Id1 = ch7,
+    Id2 = ch3,
+    Id3 = ch10,
+    Id4 = ch2,
+    Id5 = ch5,
+    Children =
+        [{Id, {supervisor_1, start_child, []}, permanent, 1000, worker, []} ||
+            Id <- [Id1,Id2,Id3,Id4,Id5]],
+
+    {ok, SupPid}  = start_link({ok, {{rest_for_one, 2, 3600}, Children}}),
+
+
+    %% Check start order (pids are growing)
+    Which1 = supervisor:which_children(sup_test),
+    IsPid = fun({_,P,_,_}) when is_pid(P) -> true; (_) -> false end,
+    true = lists:all(IsPid,Which1),
+    SortedOnPid1 = lists:keysort(2,Which1),
+    [{Id1,Pid1,_,_},
+     {Id2,Pid2,_,_},
+     {Id3,Pid3,_,_},
+     {Id4,Pid4,_,_},
+     {Id5,Pid5,_,_}] = SortedOnPid1,
+
+    TPid = self(),
+    TraceHandler = fun({trace,P,exit,_},{Last,Ps}) when P=:=Last ->
+                           TPid ! {exited,lists:reverse([P|Ps])},
+                           {Last,Ps};
+                      ({trace,P,exit,_},{Last,Ps}) ->
+                           {Last,[P|Ps]};
+                      (_T,Acc) ->
+                           Acc
+                   end,
+
+    %% Terminate Pid3 and check that Pid4 and Pid5 are terminated in
+    %% expected order.
+    Expected1 = [Pid5,Pid4],
+    {ok,_} = dbg:tracer(process,{TraceHandler,{Pid4,[]}}),
+    [{ok,[_]} = dbg:p(P,procs) || P <- Expected1],
+    terminate(Pid3, abnormal),
+    receive {exited,ExitedPids1} ->
+            dbg:stop_clear(),
+            case ExitedPids1 of
+                Expected1 -> ok;
+                _ -> ct:fail({faulty_termination_order,
+                              {expected,Expected1},
+                              {got,ExitedPids1}})
+            end
+    after 3000 ->
+            dbg:stop_clear(),
+            ct:fail({shutdown_fail,timeout})
+    end,
+
+    %% Then check that Id3-5 are started again in correct order
+    Which2 = supervisor:which_children(sup_test),
+    true = lists:all(IsPid,Which2),
+    SortedOnPid2 = lists:keysort(2,Which2),
+    [{Id1,Pid1,_,_},
+     {Id2,Pid2,_,_},
+     {Id3,Pid32,_,_},
+     {Id4,Pid42,_,_},
+     {Id5,Pid52,_,_}] = SortedOnPid2,
+
+    %% Terminate supervisor and check that all children are terminated
+    %% in opposite start order
+    Expected2 = [Pid52,Pid42,Pid32,Pid2,Pid1],
+    {ok,_} = dbg:tracer(process,{TraceHandler,{Pid1,[]}}),
+    [{ok,[_]} = dbg:p(P,procs) || P <- Expected2],
+    exit(SupPid,shutdown),
+    receive {exited,ExitedPids2} ->
+            dbg:stop_clear(),
+            case ExitedPids2 of
+                Expected2 -> ok;
+                _ -> ct:fail({faulty_termination_order,
+                              {expected,Expected2},
+                              {got,ExitedPids2}})
+            end
+    after 3000 ->
+            dbg:stop_clear(),
+            ct:fail({shutdown_fail,timeout})
+    end,
+    ok.
+
+%% Test that a non-simple supervisor scales well for starting and
+%% stopping many children.
+scale_start_stop_many_children(_Config) ->
+    process_flag(trap_exit, true),
+    {ok, _Pid}  = start_link({ok, {{one_for_one, 2, 3600}, []}}),
+    N1 = 1000,
+    N2 = 100000,
+    Ids1 = lists:seq(1,N1),
+    Ids2 = lists:seq(1,N2),
+    Children1 = [{Id,{supervisor_1,start_child,[]},permanent,1000,worker,[]} ||
+                    Id <- Ids1],
+    Children2 = [{Id,{supervisor_1,start_child,[]},permanent,1000,worker,[]} ||
+                    Id <- Ids2],
+
+    {StartT1,_} =
+        timer:tc(fun() ->
+                         [supervisor:start_child(sup_test,C) || C <- Children1]
+                 end),
+    {StopT1,_} =
+        timer:tc(fun() ->
+                         [supervisor:terminate_child(sup_test,I) || I <- Ids1]
+                 end),
+    ct:log("~w children, start time: ~w ms, stop time: ~w ms",
+           [N1, StartT1 div 1000, StopT1 div 1000]),
+
+    {StartT2,_} =
+        timer:tc(fun() ->
+                         [supervisor:start_child(sup_test,C) || C <- Children2]
+                 end),
+    {StopT2,_} =
+        timer:tc(fun() ->
+                         [supervisor:terminate_child(sup_test,I) || I <- Ids2]
+                 end),
+    ct:log("~w children, start time: ~w ms, stop time: ~w ms",
+           [N2, StartT2 div 1000, StopT2 div 1000]),
+
+    %% Scaling should be more or less linear, but allowing a bit more
+    %% to avoid false alarms
+    ScaleLimit = (N2 div N1) * 10,
+    StartScale = StartT2 div StartT1,
+    StopScale = StopT2 div StopT1,
+
+    ct:log("Scale limit: ~w~nStart scale: ~w~nStop scale: ~w",
+           [ScaleLimit, StartScale, StopScale]),
+
+    if StartScale > ScaleLimit ->
+            ct:fail({bad_start_scale,StartScale});
+       StopScale > ScaleLimit ->
+            ct:fail({bad_stop_scale,StopScale});
+       true ->
+            ok
+    end,
+
+    ok.
+
 %%-------------------------------------------------------------------------
 terminate(Pid, Reason) when Reason =/= supervisor ->
     terminate(dummy, Pid, dummy, Reason).
diff --git a/lib/stdlib/test/supervisor_deadlock.erl b/lib/stdlib/test/supervisor_deadlock.erl
index 8d3d1c6f30..f51aecccb2 100644
--- a/lib/stdlib/test/supervisor_deadlock.erl
+++ b/lib/stdlib/test/supervisor_deadlock.erl
@@ -1,5 +1,5 @@
 -module(supervisor_deadlock).
--compile(export_all).
+-compile([export_all,nowarn_export_all]).
 
 
 %%%-----------------------------------------------------------------
diff --git a/lib/stdlib/test/unicode_util_SUITE.erl b/lib/stdlib/test/unicode_util_SUITE.erl
index a89627eba5..632d9ae6e6 100644
--- a/lib/stdlib/test/unicode_util_SUITE.erl
+++ b/lib/stdlib/test/unicode_util_SUITE.erl
@@ -29,7 +29,9 @@
          get/1,
          count/1]).
 
--export([debug/0, id/1, bin_split/1, uc_loaded_size/0]).
+-export([debug/0, id/1, bin_split/1, uc_loaded_size/0,
+        time_count/4  %% Used by stdlib_bench_SUITE
+        ]).
 
 suite() ->
     [{ct_hooks,[ts_install_cth]},
@@ -334,7 +336,7 @@ do_measure(Config) ->
     File =  DataDir ++ "/NormalizationTest.txt",
     {ok, Bin} = file:read_file(File),
     Do = fun(Func, Mode) ->
-                 {N, Mean, Stddev, Res} = time_count(Func, Mode, Bin),
+                 {N, Mean, Stddev, Res} = time_count(Func, Mode, Bin, 10),
                  io:format("~4w ~6w ~.10w ~.6wms ±~.2wms #~.2w~n",
                            [Func, Mode, Res, Mean div 1000, Stddev div 1000, N])
          end,
@@ -356,19 +358,19 @@ uc_loaded_size([_|Rest]) ->
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-time_count(Fun, Mode, Bin) ->
+time_count(Fun, Mode, Bin, Repeat) ->
     timer:sleep(100), %% Let emulator catch up and clean things before test runs
     Self = self(),
     Pid = spawn_link(fun() ->
                              Str = mode(Mode, Bin),
-                             Self ! {self(),do_count(0,0,0, Fun, Str, undefined)}
+                             Self ! {self(),do_count(0,0,0, Fun, Str, undefined, Repeat)}
                      end),
     receive {Pid,Msg} -> Msg end.
 
-do_count(N,Sum,SumSq, Fun, Str, _) when N < 10 ->
+do_count(N,Sum,SumSq, Fun, Str, _, Repeat) when N < Repeat ->
     {Time, Res} = do_count(Fun, Str),
-    do_count(N+1,Sum+Time,SumSq+Time*Time, Fun, Str, Res);
-do_count(N,Sum,SumSq, _, _, Res) ->
+    do_count(N+1,Sum+Time,SumSq+Time*Time, Fun, Str, Res, Repeat);
+do_count(N,Sum,SumSq, _, _, Res, _) ->
     Mean = round(Sum / N),
     Stdev = round(math:sqrt((SumSq - (Sum*Sum/N))/(N - 1))),
     {N, Mean, Stdev, Res}.
diff --git a/lib/stdlib/test/unicode_util_SUITE_data/GraphemeBreakTest.txt b/lib/stdlib/test/unicode_util_SUITE_data/GraphemeBreakTest.txt
index 4bb4b1369b..d7d8f90de0 100644
--- a/lib/stdlib/test/unicode_util_SUITE_data/GraphemeBreakTest.txt
+++ b/lib/stdlib/test/unicode_util_SUITE_data/GraphemeBreakTest.txt
@@ -1,23 +1,24 @@
-# GraphemeBreakTest-9.0.0.txt
-# Date: 2016-06-02, 18:28:17 GMT
-# © 2016 Unicode®, Inc.
+# GraphemeBreakTest-10.0.0.txt
+# Date: 2017-04-14, 05:40:29 GMT
+# © 2017 Unicode®, Inc.
 # Unicode and the Unicode Logo are registered trademarks of Unicode, Inc. in the U.S. and other countries.
 # For terms of use, see http://www.unicode.org/terms_of_use.html
 #
 # Unicode Character Database
 #   For documentation, see http://www.unicode.org/reports/tr44/
 #
-# Default Grapheme Break Test
+# Default Grapheme_Cluster_Break Test
 #
 # Format:
-# <string> (# <comment>)? 
-#  <string> contains hex Unicode code points, with 
-#	÷ wherever there is a break opportunity, and 
+# <string> (# <comment>)?
+#  <string> contains hex Unicode code points, with
+#	÷ wherever there is a break opportunity, and
 #	× wherever there is not.
 #  <comment> the format can change, but currently it shows:
 #	- the sample character name
 #	- (x) the Grapheme_Cluster_Break property value for the sample character
-#	- [x] the rule that determines whether there is a break or not
+#	- [x] the rule that determines whether there is a break or not,
+#	   as listed in the Rules section of GraphemeBreakTest.html
 #
 # These samples may be extended or changed in the future.
 #
@@ -53,8 +54,8 @@
 ÷ 0020 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] SPACE (Other) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 0020 × 200D ÷	#  ÷ [0.2] SPACE (Other) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 0020 × 0308 × 200D ÷	#  ÷ [0.2] SPACE (Other) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 0020 ÷ 2764 ÷	#  ÷ [0.2] SPACE (Other) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 0020 × 0308 ÷ 2764 ÷	#  ÷ [0.2] SPACE (Other) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 0020 ÷ 2640 ÷	#  ÷ [0.2] SPACE (Other) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 0020 × 0308 ÷ 2640 ÷	#  ÷ [0.2] SPACE (Other) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 0020 ÷ 1F466 ÷	#  ÷ [0.2] SPACE (Other) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 0020 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] SPACE (Other) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 0020 ÷ 0378 ÷	#  ÷ [0.2] SPACE (Other) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -93,8 +94,8 @@
 ÷ 000D ÷ 0308 ÷ 1F3FB ÷	#  ÷ [0.2] <CARRIAGE RETURN (CR)> (CR) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 000D ÷ 200D ÷	#  ÷ [0.2] <CARRIAGE RETURN (CR)> (CR) ÷ [4.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 000D ÷ 0308 × 200D ÷	#  ÷ [0.2] <CARRIAGE RETURN (CR)> (CR) ÷ [4.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 000D ÷ 2764 ÷	#  ÷ [0.2] <CARRIAGE RETURN (CR)> (CR) ÷ [4.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 000D ÷ 0308 ÷ 2764 ÷	#  ÷ [0.2] <CARRIAGE RETURN (CR)> (CR) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 000D ÷ 2640 ÷	#  ÷ [0.2] <CARRIAGE RETURN (CR)> (CR) ÷ [4.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 000D ÷ 0308 ÷ 2640 ÷	#  ÷ [0.2] <CARRIAGE RETURN (CR)> (CR) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 000D ÷ 1F466 ÷	#  ÷ [0.2] <CARRIAGE RETURN (CR)> (CR) ÷ [4.0] BOY (EBG) ÷ [0.3]
 ÷ 000D ÷ 0308 ÷ 1F466 ÷	#  ÷ [0.2] <CARRIAGE RETURN (CR)> (CR) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 000D ÷ 0378 ÷	#  ÷ [0.2] <CARRIAGE RETURN (CR)> (CR) ÷ [4.0] <reserved-0378> (Other) ÷ [0.3]
@@ -133,8 +134,8 @@
 ÷ 000A ÷ 0308 ÷ 1F3FB ÷	#  ÷ [0.2] <LINE FEED (LF)> (LF) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 000A ÷ 200D ÷	#  ÷ [0.2] <LINE FEED (LF)> (LF) ÷ [4.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 000A ÷ 0308 × 200D ÷	#  ÷ [0.2] <LINE FEED (LF)> (LF) ÷ [4.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 000A ÷ 2764 ÷	#  ÷ [0.2] <LINE FEED (LF)> (LF) ÷ [4.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 000A ÷ 0308 ÷ 2764 ÷	#  ÷ [0.2] <LINE FEED (LF)> (LF) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 000A ÷ 2640 ÷	#  ÷ [0.2] <LINE FEED (LF)> (LF) ÷ [4.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 000A ÷ 0308 ÷ 2640 ÷	#  ÷ [0.2] <LINE FEED (LF)> (LF) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 000A ÷ 1F466 ÷	#  ÷ [0.2] <LINE FEED (LF)> (LF) ÷ [4.0] BOY (EBG) ÷ [0.3]
 ÷ 000A ÷ 0308 ÷ 1F466 ÷	#  ÷ [0.2] <LINE FEED (LF)> (LF) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 000A ÷ 0378 ÷	#  ÷ [0.2] <LINE FEED (LF)> (LF) ÷ [4.0] <reserved-0378> (Other) ÷ [0.3]
@@ -173,8 +174,8 @@
 ÷ 0001 ÷ 0308 ÷ 1F3FB ÷	#  ÷ [0.2] <START OF HEADING> (Control) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 0001 ÷ 200D ÷	#  ÷ [0.2] <START OF HEADING> (Control) ÷ [4.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 0001 ÷ 0308 × 200D ÷	#  ÷ [0.2] <START OF HEADING> (Control) ÷ [4.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 0001 ÷ 2764 ÷	#  ÷ [0.2] <START OF HEADING> (Control) ÷ [4.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 0001 ÷ 0308 ÷ 2764 ÷	#  ÷ [0.2] <START OF HEADING> (Control) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 0001 ÷ 2640 ÷	#  ÷ [0.2] <START OF HEADING> (Control) ÷ [4.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 0001 ÷ 0308 ÷ 2640 ÷	#  ÷ [0.2] <START OF HEADING> (Control) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 0001 ÷ 1F466 ÷	#  ÷ [0.2] <START OF HEADING> (Control) ÷ [4.0] BOY (EBG) ÷ [0.3]
 ÷ 0001 ÷ 0308 ÷ 1F466 ÷	#  ÷ [0.2] <START OF HEADING> (Control) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 0001 ÷ 0378 ÷	#  ÷ [0.2] <START OF HEADING> (Control) ÷ [4.0] <reserved-0378> (Other) ÷ [0.3]
@@ -213,8 +214,8 @@
 ÷ 0300 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] COMBINING GRAVE ACCENT (Extend) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 0300 × 200D ÷	#  ÷ [0.2] COMBINING GRAVE ACCENT (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 0300 × 0308 × 200D ÷	#  ÷ [0.2] COMBINING GRAVE ACCENT (Extend) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 0300 ÷ 2764 ÷	#  ÷ [0.2] COMBINING GRAVE ACCENT (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 0300 × 0308 ÷ 2764 ÷	#  ÷ [0.2] COMBINING GRAVE ACCENT (Extend) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 0300 ÷ 2640 ÷	#  ÷ [0.2] COMBINING GRAVE ACCENT (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 0300 × 0308 ÷ 2640 ÷	#  ÷ [0.2] COMBINING GRAVE ACCENT (Extend) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 0300 ÷ 1F466 ÷	#  ÷ [0.2] COMBINING GRAVE ACCENT (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 0300 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] COMBINING GRAVE ACCENT (Extend) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 0300 ÷ 0378 ÷	#  ÷ [0.2] COMBINING GRAVE ACCENT (Extend) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -253,8 +254,8 @@
 ÷ 0600 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] ARABIC NUMBER SIGN (Prepend) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 0600 × 200D ÷	#  ÷ [0.2] ARABIC NUMBER SIGN (Prepend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 0600 × 0308 × 200D ÷	#  ÷ [0.2] ARABIC NUMBER SIGN (Prepend) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 0600 × 2764 ÷	#  ÷ [0.2] ARABIC NUMBER SIGN (Prepend) × [9.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 0600 × 0308 ÷ 2764 ÷	#  ÷ [0.2] ARABIC NUMBER SIGN (Prepend) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 0600 × 2640 ÷	#  ÷ [0.2] ARABIC NUMBER SIGN (Prepend) × [9.2] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 0600 × 0308 ÷ 2640 ÷	#  ÷ [0.2] ARABIC NUMBER SIGN (Prepend) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 0600 × 1F466 ÷	#  ÷ [0.2] ARABIC NUMBER SIGN (Prepend) × [9.2] BOY (EBG) ÷ [0.3]
 ÷ 0600 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] ARABIC NUMBER SIGN (Prepend) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 0600 × 0378 ÷	#  ÷ [0.2] ARABIC NUMBER SIGN (Prepend) × [9.2] <reserved-0378> (Other) ÷ [0.3]
@@ -293,8 +294,8 @@
 ÷ 0903 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] DEVANAGARI SIGN VISARGA (SpacingMark) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 0903 × 200D ÷	#  ÷ [0.2] DEVANAGARI SIGN VISARGA (SpacingMark) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 0903 × 0308 × 200D ÷	#  ÷ [0.2] DEVANAGARI SIGN VISARGA (SpacingMark) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 0903 ÷ 2764 ÷	#  ÷ [0.2] DEVANAGARI SIGN VISARGA (SpacingMark) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 0903 × 0308 ÷ 2764 ÷	#  ÷ [0.2] DEVANAGARI SIGN VISARGA (SpacingMark) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 0903 ÷ 2640 ÷	#  ÷ [0.2] DEVANAGARI SIGN VISARGA (SpacingMark) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 0903 × 0308 ÷ 2640 ÷	#  ÷ [0.2] DEVANAGARI SIGN VISARGA (SpacingMark) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 0903 ÷ 1F466 ÷	#  ÷ [0.2] DEVANAGARI SIGN VISARGA (SpacingMark) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 0903 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] DEVANAGARI SIGN VISARGA (SpacingMark) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 0903 ÷ 0378 ÷	#  ÷ [0.2] DEVANAGARI SIGN VISARGA (SpacingMark) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -333,8 +334,8 @@
 ÷ 1100 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] HANGUL CHOSEONG KIYEOK (L) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 1100 × 200D ÷	#  ÷ [0.2] HANGUL CHOSEONG KIYEOK (L) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 1100 × 0308 × 200D ÷	#  ÷ [0.2] HANGUL CHOSEONG KIYEOK (L) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 1100 ÷ 2764 ÷	#  ÷ [0.2] HANGUL CHOSEONG KIYEOK (L) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 1100 × 0308 ÷ 2764 ÷	#  ÷ [0.2] HANGUL CHOSEONG KIYEOK (L) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 1100 ÷ 2640 ÷	#  ÷ [0.2] HANGUL CHOSEONG KIYEOK (L) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 1100 × 0308 ÷ 2640 ÷	#  ÷ [0.2] HANGUL CHOSEONG KIYEOK (L) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 1100 ÷ 1F466 ÷	#  ÷ [0.2] HANGUL CHOSEONG KIYEOK (L) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 1100 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] HANGUL CHOSEONG KIYEOK (L) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 1100 ÷ 0378 ÷	#  ÷ [0.2] HANGUL CHOSEONG KIYEOK (L) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -373,8 +374,8 @@
 ÷ 1160 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] HANGUL JUNGSEONG FILLER (V) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 1160 × 200D ÷	#  ÷ [0.2] HANGUL JUNGSEONG FILLER (V) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 1160 × 0308 × 200D ÷	#  ÷ [0.2] HANGUL JUNGSEONG FILLER (V) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 1160 ÷ 2764 ÷	#  ÷ [0.2] HANGUL JUNGSEONG FILLER (V) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 1160 × 0308 ÷ 2764 ÷	#  ÷ [0.2] HANGUL JUNGSEONG FILLER (V) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 1160 ÷ 2640 ÷	#  ÷ [0.2] HANGUL JUNGSEONG FILLER (V) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 1160 × 0308 ÷ 2640 ÷	#  ÷ [0.2] HANGUL JUNGSEONG FILLER (V) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 1160 ÷ 1F466 ÷	#  ÷ [0.2] HANGUL JUNGSEONG FILLER (V) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 1160 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] HANGUL JUNGSEONG FILLER (V) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 1160 ÷ 0378 ÷	#  ÷ [0.2] HANGUL JUNGSEONG FILLER (V) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -413,8 +414,8 @@
 ÷ 11A8 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] HANGUL JONGSEONG KIYEOK (T) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 11A8 × 200D ÷	#  ÷ [0.2] HANGUL JONGSEONG KIYEOK (T) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 11A8 × 0308 × 200D ÷	#  ÷ [0.2] HANGUL JONGSEONG KIYEOK (T) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 11A8 ÷ 2764 ÷	#  ÷ [0.2] HANGUL JONGSEONG KIYEOK (T) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 11A8 × 0308 ÷ 2764 ÷	#  ÷ [0.2] HANGUL JONGSEONG KIYEOK (T) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 11A8 ÷ 2640 ÷	#  ÷ [0.2] HANGUL JONGSEONG KIYEOK (T) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 11A8 × 0308 ÷ 2640 ÷	#  ÷ [0.2] HANGUL JONGSEONG KIYEOK (T) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 11A8 ÷ 1F466 ÷	#  ÷ [0.2] HANGUL JONGSEONG KIYEOK (T) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 11A8 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] HANGUL JONGSEONG KIYEOK (T) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 11A8 ÷ 0378 ÷	#  ÷ [0.2] HANGUL JONGSEONG KIYEOK (T) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -453,8 +454,8 @@
 ÷ AC00 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] HANGUL SYLLABLE GA (LV) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ AC00 × 200D ÷	#  ÷ [0.2] HANGUL SYLLABLE GA (LV) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ AC00 × 0308 × 200D ÷	#  ÷ [0.2] HANGUL SYLLABLE GA (LV) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ AC00 ÷ 2764 ÷	#  ÷ [0.2] HANGUL SYLLABLE GA (LV) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ AC00 × 0308 ÷ 2764 ÷	#  ÷ [0.2] HANGUL SYLLABLE GA (LV) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ AC00 ÷ 2640 ÷	#  ÷ [0.2] HANGUL SYLLABLE GA (LV) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ AC00 × 0308 ÷ 2640 ÷	#  ÷ [0.2] HANGUL SYLLABLE GA (LV) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ AC00 ÷ 1F466 ÷	#  ÷ [0.2] HANGUL SYLLABLE GA (LV) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ AC00 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] HANGUL SYLLABLE GA (LV) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ AC00 ÷ 0378 ÷	#  ÷ [0.2] HANGUL SYLLABLE GA (LV) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -493,8 +494,8 @@
 ÷ AC01 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] HANGUL SYLLABLE GAG (LVT) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ AC01 × 200D ÷	#  ÷ [0.2] HANGUL SYLLABLE GAG (LVT) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ AC01 × 0308 × 200D ÷	#  ÷ [0.2] HANGUL SYLLABLE GAG (LVT) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ AC01 ÷ 2764 ÷	#  ÷ [0.2] HANGUL SYLLABLE GAG (LVT) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ AC01 × 0308 ÷ 2764 ÷	#  ÷ [0.2] HANGUL SYLLABLE GAG (LVT) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ AC01 ÷ 2640 ÷	#  ÷ [0.2] HANGUL SYLLABLE GAG (LVT) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ AC01 × 0308 ÷ 2640 ÷	#  ÷ [0.2] HANGUL SYLLABLE GAG (LVT) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ AC01 ÷ 1F466 ÷	#  ÷ [0.2] HANGUL SYLLABLE GAG (LVT) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ AC01 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] HANGUL SYLLABLE GAG (LVT) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ AC01 ÷ 0378 ÷	#  ÷ [0.2] HANGUL SYLLABLE GAG (LVT) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -533,8 +534,8 @@
 ÷ 1F1E6 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] REGIONAL INDICATOR SYMBOL LETTER A (RI) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 1F1E6 × 200D ÷	#  ÷ [0.2] REGIONAL INDICATOR SYMBOL LETTER A (RI) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 1F1E6 × 0308 × 200D ÷	#  ÷ [0.2] REGIONAL INDICATOR SYMBOL LETTER A (RI) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 1F1E6 ÷ 2764 ÷	#  ÷ [0.2] REGIONAL INDICATOR SYMBOL LETTER A (RI) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 1F1E6 × 0308 ÷ 2764 ÷	#  ÷ [0.2] REGIONAL INDICATOR SYMBOL LETTER A (RI) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 1F1E6 ÷ 2640 ÷	#  ÷ [0.2] REGIONAL INDICATOR SYMBOL LETTER A (RI) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 1F1E6 × 0308 ÷ 2640 ÷	#  ÷ [0.2] REGIONAL INDICATOR SYMBOL LETTER A (RI) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 1F1E6 ÷ 1F466 ÷	#  ÷ [0.2] REGIONAL INDICATOR SYMBOL LETTER A (RI) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 1F1E6 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] REGIONAL INDICATOR SYMBOL LETTER A (RI) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 1F1E6 ÷ 0378 ÷	#  ÷ [0.2] REGIONAL INDICATOR SYMBOL LETTER A (RI) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -573,8 +574,8 @@
 ÷ 261D × 0308 × 1F3FB ÷	#  ÷ [0.2] WHITE UP POINTING INDEX (E_Base) × [9.0] COMBINING DIAERESIS (Extend) × [10.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 261D × 200D ÷	#  ÷ [0.2] WHITE UP POINTING INDEX (E_Base) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 261D × 0308 × 200D ÷	#  ÷ [0.2] WHITE UP POINTING INDEX (E_Base) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 261D ÷ 2764 ÷	#  ÷ [0.2] WHITE UP POINTING INDEX (E_Base) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 261D × 0308 ÷ 2764 ÷	#  ÷ [0.2] WHITE UP POINTING INDEX (E_Base) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 261D ÷ 2640 ÷	#  ÷ [0.2] WHITE UP POINTING INDEX (E_Base) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 261D × 0308 ÷ 2640 ÷	#  ÷ [0.2] WHITE UP POINTING INDEX (E_Base) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 261D ÷ 1F466 ÷	#  ÷ [0.2] WHITE UP POINTING INDEX (E_Base) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 261D × 0308 ÷ 1F466 ÷	#  ÷ [0.2] WHITE UP POINTING INDEX (E_Base) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 261D ÷ 0378 ÷	#  ÷ [0.2] WHITE UP POINTING INDEX (E_Base) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -613,8 +614,8 @@
 ÷ 1F3FB × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 1F3FB × 200D ÷	#  ÷ [0.2] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 1F3FB × 0308 × 200D ÷	#  ÷ [0.2] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 1F3FB ÷ 2764 ÷	#  ÷ [0.2] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 1F3FB × 0308 ÷ 2764 ÷	#  ÷ [0.2] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 1F3FB ÷ 2640 ÷	#  ÷ [0.2] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 1F3FB × 0308 ÷ 2640 ÷	#  ÷ [0.2] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 1F3FB ÷ 1F466 ÷	#  ÷ [0.2] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 1F3FB × 0308 ÷ 1F466 ÷	#  ÷ [0.2] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 1F3FB ÷ 0378 ÷	#  ÷ [0.2] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -653,54 +654,54 @@
 ÷ 200D × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 200D × 200D ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 200D × 0308 × 200D ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 200D × 2764 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [11.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 200D × 0308 ÷ 2764 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 200D × 2640 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [11.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 200D × 0308 ÷ 2640 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 200D × 1F466 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [11.0] BOY (EBG) ÷ [0.3]
 ÷ 200D × 0308 ÷ 1F466 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 200D ÷ 0378 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
 ÷ 200D × 0308 ÷ 0378 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
 ÷ 200D ÷ D800 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) ÷ [5.0] <surrogate-D800> (Control) ÷ [0.3]
 ÷ 200D × 0308 ÷ D800 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [9.0] COMBINING DIAERESIS (Extend) ÷ [5.0] <surrogate-D800> (Control) ÷ [0.3]
-÷ 2764 ÷ 0020 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] SPACE (Other) ÷ [0.3]
-÷ 2764 × 0308 ÷ 0020 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] SPACE (Other) ÷ [0.3]
-÷ 2764 ÷ 000D ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [5.0] <CARRIAGE RETURN (CR)> (CR) ÷ [0.3]
-÷ 2764 × 0308 ÷ 000D ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [5.0] <CARRIAGE RETURN (CR)> (CR) ÷ [0.3]
-÷ 2764 ÷ 000A ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [5.0] <LINE FEED (LF)> (LF) ÷ [0.3]
-÷ 2764 × 0308 ÷ 000A ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [5.0] <LINE FEED (LF)> (LF) ÷ [0.3]
-÷ 2764 ÷ 0001 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [5.0] <START OF HEADING> (Control) ÷ [0.3]
-÷ 2764 × 0308 ÷ 0001 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [5.0] <START OF HEADING> (Control) ÷ [0.3]
-÷ 2764 × 0300 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING GRAVE ACCENT (Extend) ÷ [0.3]
-÷ 2764 × 0308 × 0300 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] COMBINING GRAVE ACCENT (Extend) ÷ [0.3]
-÷ 2764 ÷ 0600 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] ARABIC NUMBER SIGN (Prepend) ÷ [0.3]
-÷ 2764 × 0308 ÷ 0600 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] ARABIC NUMBER SIGN (Prepend) ÷ [0.3]
-÷ 2764 × 0903 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.1] DEVANAGARI SIGN VISARGA (SpacingMark) ÷ [0.3]
-÷ 2764 × 0308 × 0903 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) × [9.1] DEVANAGARI SIGN VISARGA (SpacingMark) ÷ [0.3]
-÷ 2764 ÷ 1100 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] HANGUL CHOSEONG KIYEOK (L) ÷ [0.3]
-÷ 2764 × 0308 ÷ 1100 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HANGUL CHOSEONG KIYEOK (L) ÷ [0.3]
-÷ 2764 ÷ 1160 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] HANGUL JUNGSEONG FILLER (V) ÷ [0.3]
-÷ 2764 × 0308 ÷ 1160 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HANGUL JUNGSEONG FILLER (V) ÷ [0.3]
-÷ 2764 ÷ 11A8 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] HANGUL JONGSEONG KIYEOK (T) ÷ [0.3]
-÷ 2764 × 0308 ÷ 11A8 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HANGUL JONGSEONG KIYEOK (T) ÷ [0.3]
-÷ 2764 ÷ AC00 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] HANGUL SYLLABLE GA (LV) ÷ [0.3]
-÷ 2764 × 0308 ÷ AC00 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HANGUL SYLLABLE GA (LV) ÷ [0.3]
-÷ 2764 ÷ AC01 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] HANGUL SYLLABLE GAG (LVT) ÷ [0.3]
-÷ 2764 × 0308 ÷ AC01 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HANGUL SYLLABLE GAG (LVT) ÷ [0.3]
-÷ 2764 ÷ 1F1E6 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] REGIONAL INDICATOR SYMBOL LETTER A (RI) ÷ [0.3]
-÷ 2764 × 0308 ÷ 1F1E6 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] REGIONAL INDICATOR SYMBOL LETTER A (RI) ÷ [0.3]
-÷ 2764 ÷ 261D ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] WHITE UP POINTING INDEX (E_Base) ÷ [0.3]
-÷ 2764 × 0308 ÷ 261D ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] WHITE UP POINTING INDEX (E_Base) ÷ [0.3]
-÷ 2764 ÷ 1F3FB ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
-÷ 2764 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
-÷ 2764 × 200D ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 2764 × 0308 × 200D ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 2764 ÷ 2764 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 2764 × 0308 ÷ 2764 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 2764 ÷ 1F466 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] BOY (EBG) ÷ [0.3]
-÷ 2764 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
-÷ 2764 ÷ 0378 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
-÷ 2764 × 0308 ÷ 0378 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
-÷ 2764 ÷ D800 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [5.0] <surrogate-D800> (Control) ÷ [0.3]
-÷ 2764 × 0308 ÷ D800 ÷	#  ÷ [0.2] HEAVY BLACK HEART (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [5.0] <surrogate-D800> (Control) ÷ [0.3]
+÷ 2640 ÷ 0020 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] SPACE (Other) ÷ [0.3]
+÷ 2640 × 0308 ÷ 0020 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] SPACE (Other) ÷ [0.3]
+÷ 2640 ÷ 000D ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [5.0] <CARRIAGE RETURN (CR)> (CR) ÷ [0.3]
+÷ 2640 × 0308 ÷ 000D ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [5.0] <CARRIAGE RETURN (CR)> (CR) ÷ [0.3]
+÷ 2640 ÷ 000A ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [5.0] <LINE FEED (LF)> (LF) ÷ [0.3]
+÷ 2640 × 0308 ÷ 000A ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [5.0] <LINE FEED (LF)> (LF) ÷ [0.3]
+÷ 2640 ÷ 0001 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [5.0] <START OF HEADING> (Control) ÷ [0.3]
+÷ 2640 × 0308 ÷ 0001 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [5.0] <START OF HEADING> (Control) ÷ [0.3]
+÷ 2640 × 0300 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING GRAVE ACCENT (Extend) ÷ [0.3]
+÷ 2640 × 0308 × 0300 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] COMBINING GRAVE ACCENT (Extend) ÷ [0.3]
+÷ 2640 ÷ 0600 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] ARABIC NUMBER SIGN (Prepend) ÷ [0.3]
+÷ 2640 × 0308 ÷ 0600 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] ARABIC NUMBER SIGN (Prepend) ÷ [0.3]
+÷ 2640 × 0903 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.1] DEVANAGARI SIGN VISARGA (SpacingMark) ÷ [0.3]
+÷ 2640 × 0308 × 0903 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) × [9.1] DEVANAGARI SIGN VISARGA (SpacingMark) ÷ [0.3]
+÷ 2640 ÷ 1100 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] HANGUL CHOSEONG KIYEOK (L) ÷ [0.3]
+÷ 2640 × 0308 ÷ 1100 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HANGUL CHOSEONG KIYEOK (L) ÷ [0.3]
+÷ 2640 ÷ 1160 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] HANGUL JUNGSEONG FILLER (V) ÷ [0.3]
+÷ 2640 × 0308 ÷ 1160 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HANGUL JUNGSEONG FILLER (V) ÷ [0.3]
+÷ 2640 ÷ 11A8 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] HANGUL JONGSEONG KIYEOK (T) ÷ [0.3]
+÷ 2640 × 0308 ÷ 11A8 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HANGUL JONGSEONG KIYEOK (T) ÷ [0.3]
+÷ 2640 ÷ AC00 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] HANGUL SYLLABLE GA (LV) ÷ [0.3]
+÷ 2640 × 0308 ÷ AC00 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HANGUL SYLLABLE GA (LV) ÷ [0.3]
+÷ 2640 ÷ AC01 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] HANGUL SYLLABLE GAG (LVT) ÷ [0.3]
+÷ 2640 × 0308 ÷ AC01 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HANGUL SYLLABLE GAG (LVT) ÷ [0.3]
+÷ 2640 ÷ 1F1E6 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] REGIONAL INDICATOR SYMBOL LETTER A (RI) ÷ [0.3]
+÷ 2640 × 0308 ÷ 1F1E6 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] REGIONAL INDICATOR SYMBOL LETTER A (RI) ÷ [0.3]
+÷ 2640 ÷ 261D ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] WHITE UP POINTING INDEX (E_Base) ÷ [0.3]
+÷ 2640 × 0308 ÷ 261D ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] WHITE UP POINTING INDEX (E_Base) ÷ [0.3]
+÷ 2640 ÷ 1F3FB ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
+÷ 2640 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
+÷ 2640 × 200D ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
+÷ 2640 × 0308 × 200D ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
+÷ 2640 ÷ 2640 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 2640 × 0308 ÷ 2640 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 2640 ÷ 1F466 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] BOY (EBG) ÷ [0.3]
+÷ 2640 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
+÷ 2640 ÷ 0378 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
+÷ 2640 × 0308 ÷ 0378 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
+÷ 2640 ÷ D800 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) ÷ [5.0] <surrogate-D800> (Control) ÷ [0.3]
+÷ 2640 × 0308 ÷ D800 ÷	#  ÷ [0.2] FEMALE SIGN (Glue_After_Zwj) × [9.0] COMBINING DIAERESIS (Extend) ÷ [5.0] <surrogate-D800> (Control) ÷ [0.3]
 ÷ 1F466 ÷ 0020 ÷	#  ÷ [0.2] BOY (EBG) ÷ [999.0] SPACE (Other) ÷ [0.3]
 ÷ 1F466 × 0308 ÷ 0020 ÷	#  ÷ [0.2] BOY (EBG) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] SPACE (Other) ÷ [0.3]
 ÷ 1F466 ÷ 000D ÷	#  ÷ [0.2] BOY (EBG) ÷ [5.0] <CARRIAGE RETURN (CR)> (CR) ÷ [0.3]
@@ -733,8 +734,8 @@
 ÷ 1F466 × 0308 × 1F3FB ÷	#  ÷ [0.2] BOY (EBG) × [9.0] COMBINING DIAERESIS (Extend) × [10.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 1F466 × 200D ÷	#  ÷ [0.2] BOY (EBG) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 1F466 × 0308 × 200D ÷	#  ÷ [0.2] BOY (EBG) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 1F466 ÷ 2764 ÷	#  ÷ [0.2] BOY (EBG) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 1F466 × 0308 ÷ 2764 ÷	#  ÷ [0.2] BOY (EBG) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 1F466 ÷ 2640 ÷	#  ÷ [0.2] BOY (EBG) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 1F466 × 0308 ÷ 2640 ÷	#  ÷ [0.2] BOY (EBG) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 1F466 ÷ 1F466 ÷	#  ÷ [0.2] BOY (EBG) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 1F466 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] BOY (EBG) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 1F466 ÷ 0378 ÷	#  ÷ [0.2] BOY (EBG) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -773,8 +774,8 @@
 ÷ 0378 × 0308 ÷ 1F3FB ÷	#  ÷ [0.2] <reserved-0378> (Other) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 0378 × 200D ÷	#  ÷ [0.2] <reserved-0378> (Other) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ 0378 × 0308 × 200D ÷	#  ÷ [0.2] <reserved-0378> (Other) × [9.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ 0378 ÷ 2764 ÷	#  ÷ [0.2] <reserved-0378> (Other) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ 0378 × 0308 ÷ 2764 ÷	#  ÷ [0.2] <reserved-0378> (Other) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 0378 ÷ 2640 ÷	#  ÷ [0.2] <reserved-0378> (Other) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ 0378 × 0308 ÷ 2640 ÷	#  ÷ [0.2] <reserved-0378> (Other) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 0378 ÷ 1F466 ÷	#  ÷ [0.2] <reserved-0378> (Other) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 0378 × 0308 ÷ 1F466 ÷	#  ÷ [0.2] <reserved-0378> (Other) × [9.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ 0378 ÷ 0378 ÷	#  ÷ [0.2] <reserved-0378> (Other) ÷ [999.0] <reserved-0378> (Other) ÷ [0.3]
@@ -813,8 +814,8 @@
 ÷ D800 ÷ 0308 ÷ 1F3FB ÷	#  ÷ [0.2] <surrogate-D800> (Control) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ D800 ÷ 200D ÷	#  ÷ [0.2] <surrogate-D800> (Control) ÷ [4.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
 ÷ D800 ÷ 0308 × 200D ÷	#  ÷ [0.2] <surrogate-D800> (Control) ÷ [4.0] COMBINING DIAERESIS (Extend) × [9.0] ZERO WIDTH JOINER (ZWJ) ÷ [0.3]
-÷ D800 ÷ 2764 ÷	#  ÷ [0.2] <surrogate-D800> (Control) ÷ [4.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
-÷ D800 ÷ 0308 ÷ 2764 ÷	#  ÷ [0.2] <surrogate-D800> (Control) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ D800 ÷ 2640 ÷	#  ÷ [0.2] <surrogate-D800> (Control) ÷ [4.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
+÷ D800 ÷ 0308 ÷ 2640 ÷	#  ÷ [0.2] <surrogate-D800> (Control) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ D800 ÷ 1F466 ÷	#  ÷ [0.2] <surrogate-D800> (Control) ÷ [4.0] BOY (EBG) ÷ [0.3]
 ÷ D800 ÷ 0308 ÷ 1F466 ÷	#  ÷ [0.2] <surrogate-D800> (Control) ÷ [4.0] COMBINING DIAERESIS (Extend) ÷ [999.0] BOY (EBG) ÷ [0.3]
 ÷ D800 ÷ 0378 ÷	#  ÷ [0.2] <surrogate-D800> (Control) ÷ [4.0] <reserved-0378> (Other) ÷ [0.3]
@@ -840,7 +841,7 @@
 ÷ 261D × 1F3FB ÷ 261D ÷	#  ÷ [0.2] WHITE UP POINTING INDEX (E_Base) × [10.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [999.0] WHITE UP POINTING INDEX (E_Base) ÷ [0.3]
 ÷ 1F466 × 1F3FB ÷	#  ÷ [0.2] BOY (EBG) × [10.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
 ÷ 200D × 1F466 × 1F3FB ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [11.0] BOY (EBG) × [10.0] EMOJI MODIFIER FITZPATRICK TYPE-1-2 (E_Modifier) ÷ [0.3]
-÷ 200D × 2764 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [11.0] HEAVY BLACK HEART (Glue_After_Zwj) ÷ [0.3]
+÷ 200D × 2640 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [11.0] FEMALE SIGN (Glue_After_Zwj) ÷ [0.3]
 ÷ 200D × 1F466 ÷	#  ÷ [0.2] ZERO WIDTH JOINER (ZWJ) × [11.0] BOY (EBG) ÷ [0.3]
 ÷ 1F466 ÷ 1F466 ÷	#  ÷ [0.2] BOY (EBG) ÷ [999.0] BOY (EBG) ÷ [0.3]
 #
diff --git a/lib/stdlib/test/unicode_util_SUITE_data/LineBreakTest.txt b/lib/stdlib/test/unicode_util_SUITE_data/LineBreakTest.txt
index 05efcf5a44..6715446aba 100644
--- a/lib/stdlib/test/unicode_util_SUITE_data/LineBreakTest.txt
+++ b/lib/stdlib/test/unicode_util_SUITE_data/LineBreakTest.txt
@@ -1,25 +1,28 @@
-# LineBreakTest-9.0.0.txt
-# Date: 2016-06-18, 00:42:06 GMT
-# © 2016 Unicode®, Inc.
+# LineBreakTest-10.0.0.txt
+# Date: 2017-04-14, 05:40:30 GMT
+# © 2017 Unicode®, Inc.
 # Unicode and the Unicode Logo are registered trademarks of Unicode, Inc. in the U.S. and other countries.
 # For terms of use, see http://www.unicode.org/terms_of_use.html
 #
 # Unicode Character Database
 #   For documentation, see http://www.unicode.org/reports/tr44/
 #
-# Default Line Break Test
+# Default Line_Break Test
 #
 # Format:
-# <string> (# <comment>)? 
-#  <string> contains hex Unicode code points, with 
-#	÷ wherever there is a break opportunity, and 
+# <string> (# <comment>)?
+#  <string> contains hex Unicode code points, with
+#	÷ wherever there is a break opportunity, and
 #	× wherever there is not.
 #  <comment> the format can change, but currently it shows:
 #	- the sample character name
 #	- (x) the Line_Break property value for the sample character
-#	- [x] the rule that determines whether there is a break or not
-# Note: The Line Break tests use tailoring of numbers described in Example 7 of Section 8.2 Examples of Customization.
-# They also differ from the results produced by a pair table implementation in sequences like: ZW SP CL.
+#	- [x] the rule that determines whether there is a break or not,
+#	   as listed in the Rules section of LineBreakTest.html
+#
+# Note:
+#  The Line_Break tests use tailoring of numbers described in
+#  Example 7 of Section 8.2, "Examples of Customization" of UAX #14.
 #
 # These samples may be extended or changed in the future.
 #
diff --git a/lib/stdlib/test/unicode_util_SUITE_data/NormalizationTest.txt b/lib/stdlib/test/unicode_util_SUITE_data/NormalizationTest.txt
index e133fa8a78..71f2371c5e 100644
--- a/lib/stdlib/test/unicode_util_SUITE_data/NormalizationTest.txt
+++ b/lib/stdlib/test/unicode_util_SUITE_data/NormalizationTest.txt
@@ -1,6 +1,6 @@
-# NormalizationTest-9.0.0.txt
-# Date: 2016-04-04, 11:41:55 GMT
-# © 2016 Unicode®, Inc.
+# NormalizationTest-10.0.0.txt
+# Date: 2017-03-08, 08:41:55 GMT
+# © 2017 Unicode®, Inc.
 # Unicode and the Unicode Logo are registered trademarks of Unicode, Inc. in the U.S. and other countries.
 # For terms of use, see http://www.unicode.org/terms_of_use.html
 #
@@ -17653,6 +17653,10 @@ FFEE;FFEE;FFEE;25CB;25CB; # (￮; ￮; ￮; ○; ○; ) HALFWIDTH WHITE CIRCLE
 0061 0CBC 3099 093C 0334 0062;0061 0334 0CBC 093C 3099 0062;0061 0334 0CBC 093C 3099 0062;0061 0334 0CBC 093C 3099 0062;0061 0334 0CBC 093C 3099 0062; # (a◌಼◌゙◌़◌̴b; a◌̴◌಼◌़◌゙b; a◌̴◌಼◌़◌゙b; a◌̴◌಼◌़◌゙b; a◌̴◌಼◌़◌゙b; ) LATIN SMALL LETTER A, KANNADA SIGN NUKTA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, DEVANAGARI SIGN NUKTA, COMBINING TILDE OVERLAY, LATIN SMALL LETTER B
 0061 05B0 094D 3099 0CCD 0062;0061 3099 094D 0CCD 05B0 0062;0061 3099 094D 0CCD 05B0 0062;0061 3099 094D 0CCD 05B0 0062;0061 3099 094D 0CCD 05B0 0062; # (a◌ְ◌्◌゙◌್b; a◌゙◌्◌್◌ְb; a◌゙◌्◌್◌ְb; a◌゙◌्◌್◌ְb; a◌゙◌्◌್◌ְb; ) LATIN SMALL LETTER A, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, KANNADA SIGN VIRAMA, LATIN SMALL LETTER B
 0061 0CCD 05B0 094D 3099 0062;0061 3099 0CCD 094D 05B0 0062;0061 3099 0CCD 094D 05B0 0062;0061 3099 0CCD 094D 05B0 0062;0061 3099 0CCD 094D 05B0 0062; # (a◌್◌ְ◌्◌゙b; a◌゙◌್◌्◌ְb; a◌゙◌್◌्◌ְb; a◌゙◌್◌्◌ְb; a◌゙◌್◌्◌ְb; ) LATIN SMALL LETTER A, KANNADA SIGN VIRAMA, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, LATIN SMALL LETTER B
+0061 05B0 094D 3099 0D3B 0062;0061 3099 094D 0D3B 05B0 0062;0061 3099 094D 0D3B 05B0 0062;0061 3099 094D 0D3B 05B0 0062;0061 3099 094D 0D3B 05B0 0062; # (a◌ְ◌्◌゙◌഻b; a◌゙◌्◌഻◌ְb; a◌゙◌्◌഻◌ְb; a◌゙◌्◌഻◌ְb; a◌゙◌्◌഻◌ְb; ) LATIN SMALL LETTER A, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, MALAYALAM SIGN VERTICAL BAR VIRAMA, LATIN SMALL LETTER B
+0061 0D3B 05B0 094D 3099 0062;0061 3099 0D3B 094D 05B0 0062;0061 3099 0D3B 094D 05B0 0062;0061 3099 0D3B 094D 05B0 0062;0061 3099 0D3B 094D 05B0 0062; # (a◌഻◌ְ◌्◌゙b; a◌゙◌഻◌्◌ְb; a◌゙◌഻◌्◌ְb; a◌゙◌഻◌्◌ְb; a◌゙◌഻◌्◌ְb; ) LATIN SMALL LETTER A, MALAYALAM SIGN VERTICAL BAR VIRAMA, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, LATIN SMALL LETTER B
+0061 05B0 094D 3099 0D3C 0062;0061 3099 094D 0D3C 05B0 0062;0061 3099 094D 0D3C 05B0 0062;0061 3099 094D 0D3C 05B0 0062;0061 3099 094D 0D3C 05B0 0062; # (a◌ְ◌्◌゙◌഼b; a◌゙◌्◌഼◌ְb; a◌゙◌्◌഼◌ְb; a◌゙◌्◌഼◌ְb; a◌゙◌्◌഼◌ְb; ) LATIN SMALL LETTER A, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, MALAYALAM SIGN CIRCULAR VIRAMA, LATIN SMALL LETTER B
+0061 0D3C 05B0 094D 3099 0062;0061 3099 0D3C 094D 05B0 0062;0061 3099 0D3C 094D 05B0 0062;0061 3099 0D3C 094D 05B0 0062;0061 3099 0D3C 094D 05B0 0062; # (a◌഼◌ְ◌्◌゙b; a◌゙◌഼◌्◌ְb; a◌゙◌഼◌्◌ְb; a◌゙◌഼◌्◌ְb; a◌゙◌഼◌्◌ְb; ) LATIN SMALL LETTER A, MALAYALAM SIGN CIRCULAR VIRAMA, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, LATIN SMALL LETTER B
 0061 05B0 094D 3099 0D4D 0062;0061 3099 094D 0D4D 05B0 0062;0061 3099 094D 0D4D 05B0 0062;0061 3099 094D 0D4D 05B0 0062;0061 3099 094D 0D4D 05B0 0062; # (a◌ְ◌्◌゙◌്b; a◌゙◌्◌്◌ְb; a◌゙◌्◌്◌ְb; a◌゙◌्◌്◌ְb; a◌゙◌्◌്◌ְb; ) LATIN SMALL LETTER A, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, MALAYALAM SIGN VIRAMA, LATIN SMALL LETTER B
 0061 0D4D 05B0 094D 3099 0062;0061 3099 0D4D 094D 05B0 0062;0061 3099 0D4D 094D 05B0 0062;0061 3099 0D4D 094D 05B0 0062;0061 3099 0D4D 094D 05B0 0062; # (a◌്◌ְ◌्◌゙b; a◌゙◌്◌्◌ְb; a◌゙◌്◌्◌ְb; a◌゙◌്◌्◌ְb; a◌゙◌്◌्◌ְb; ) LATIN SMALL LETTER A, MALAYALAM SIGN VIRAMA, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, LATIN SMALL LETTER B
 0061 05B0 094D 3099 0DCA 0062;0061 3099 094D 0DCA 05B0 0062;0061 3099 094D 0DCA 05B0 0062;0061 3099 094D 0DCA 05B0 0062;0061 3099 094D 0DCA 05B0 0062; # (a◌ְ◌्◌゙◌්b; a◌゙◌्◌්◌ְb; a◌゙◌्◌්◌ְb; a◌゙◌्◌්◌ְb; a◌゙◌्◌්◌ְb; ) LATIN SMALL LETTER A, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, SINHALA SIGN AL-LAKUNA, LATIN SMALL LETTER B
@@ -17999,6 +18003,14 @@ FFEE;FFEE;FFEE;25CB;25CB; # (￮; ￮; ￮; ○; ○; ) HALFWIDTH WHITE CIRCLE
 0061 1DF4 0315 0300 05AE 0062;0061 05AE 1DF4 0300 0315 0062;0061 05AE 1DF4 0300 0315 0062;0061 05AE 1DF4 0300 0315 0062;0061 05AE 1DF4 0300 0315 0062; # (a◌ᷴ◌̕◌̀◌֮b; a◌֮◌ᷴ◌̀◌̕b; a◌֮◌ᷴ◌̀◌̕b; a◌֮◌ᷴ◌̀◌̕b; a◌֮◌ᷴ◌̀◌̕b; ) LATIN SMALL LETTER A, COMBINING LATIN SMALL LETTER U WITH DIAERESIS, COMBINING COMMA ABOVE RIGHT, COMBINING GRAVE ACCENT, HEBREW ACCENT ZINOR, LATIN SMALL LETTER B
 0061 0315 0300 05AE 1DF5 0062;00E0 05AE 1DF5 0315 0062;0061 05AE 0300 1DF5 0315 0062;00E0 05AE 1DF5 0315 0062;0061 05AE 0300 1DF5 0315 0062; # (a◌̕◌̀◌֮◌᷵b; à◌֮◌᷵◌̕b; a◌֮◌̀◌᷵◌̕b; à◌֮◌᷵◌̕b; a◌֮◌̀◌᷵◌̕b; ) LATIN SMALL LETTER A, COMBINING COMMA ABOVE RIGHT, COMBINING GRAVE ACCENT, HEBREW ACCENT ZINOR, COMBINING UP TACK ABOVE, LATIN SMALL LETTER B
 0061 1DF5 0315 0300 05AE 0062;0061 05AE 1DF5 0300 0315 0062;0061 05AE 1DF5 0300 0315 0062;0061 05AE 1DF5 0300 0315 0062;0061 05AE 1DF5 0300 0315 0062; # (a◌᷵◌̕◌̀◌֮b; a◌֮◌᷵◌̀◌̕b; a◌֮◌᷵◌̀◌̕b; a◌֮◌᷵◌̀◌̕b; a◌֮◌᷵◌̀◌̕b; ) LATIN SMALL LETTER A, COMBINING UP TACK ABOVE, COMBINING COMMA ABOVE RIGHT, COMBINING GRAVE ACCENT, HEBREW ACCENT ZINOR, LATIN SMALL LETTER B
+0061 035C 0315 0300 1DF6 0062;00E0 0315 1DF6 035C 0062;0061 0300 0315 1DF6 035C 0062;00E0 0315 1DF6 035C 0062;0061 0300 0315 1DF6 035C 0062; # (a◌͜◌̕◌̀◌᷶b; à◌̕◌᷶◌͜b; a◌̀◌̕◌᷶◌͜b; à◌̕◌᷶◌͜b; a◌̀◌̕◌᷶◌͜b; ) LATIN SMALL LETTER A, COMBINING DOUBLE BREVE BELOW, COMBINING COMMA ABOVE RIGHT, COMBINING GRAVE ACCENT, COMBINING KAVYKA ABOVE RIGHT, LATIN SMALL LETTER B
+0061 1DF6 035C 0315 0300 0062;00E0 1DF6 0315 035C 0062;0061 0300 1DF6 0315 035C 0062;00E0 1DF6 0315 035C 0062;0061 0300 1DF6 0315 035C 0062; # (a◌᷶◌͜◌̕◌̀b; à◌᷶◌̕◌͜b; a◌̀◌᷶◌̕◌͜b; à◌᷶◌̕◌͜b; a◌̀◌᷶◌̕◌͜b; ) LATIN SMALL LETTER A, COMBINING KAVYKA ABOVE RIGHT, COMBINING DOUBLE BREVE BELOW, COMBINING COMMA ABOVE RIGHT, COMBINING GRAVE ACCENT, LATIN SMALL LETTER B
+0061 0300 05AE 1D16D 1DF7 0062;00E0 1D16D 05AE 1DF7 0062;0061 1D16D 05AE 1DF7 0300 0062;00E0 1D16D 05AE 1DF7 0062;0061 1D16D 05AE 1DF7 0300 0062; # (a◌̀◌𝅭֮◌᷷b; à𝅭◌֮◌᷷b; a𝅭◌֮◌᷷◌̀b; à𝅭◌֮◌᷷b; a𝅭◌֮◌᷷◌̀b; ) LATIN SMALL LETTER A, COMBINING GRAVE ACCENT, HEBREW ACCENT ZINOR, MUSICAL SYMBOL COMBINING AUGMENTATION DOT, COMBINING KAVYKA ABOVE LEFT, LATIN SMALL LETTER B
+0061 1DF7 0300 05AE 1D16D 0062;00E0 1D16D 1DF7 05AE 0062;0061 1D16D 1DF7 05AE 0300 0062;00E0 1D16D 1DF7 05AE 0062;0061 1D16D 1DF7 05AE 0300 0062; # (a◌᷷◌̀◌𝅭֮b; à𝅭◌᷷◌֮b; a𝅭◌᷷◌֮◌̀b; à𝅭◌᷷◌֮b; a𝅭◌᷷◌֮◌̀b; ) LATIN SMALL LETTER A, COMBINING KAVYKA ABOVE LEFT, COMBINING GRAVE ACCENT, HEBREW ACCENT ZINOR, MUSICAL SYMBOL COMBINING AUGMENTATION DOT, LATIN SMALL LETTER B
+0061 0300 05AE 1D16D 1DF8 0062;00E0 1D16D 05AE 1DF8 0062;0061 1D16D 05AE 1DF8 0300 0062;00E0 1D16D 05AE 1DF8 0062;0061 1D16D 05AE 1DF8 0300 0062; # (a◌̀◌𝅭֮◌᷸b; à𝅭◌֮◌᷸b; a𝅭◌֮◌᷸◌̀b; à𝅭◌֮◌᷸b; a𝅭◌֮◌᷸◌̀b; ) LATIN SMALL LETTER A, COMBINING GRAVE ACCENT, HEBREW ACCENT ZINOR, MUSICAL SYMBOL COMBINING AUGMENTATION DOT, COMBINING DOT ABOVE LEFT, LATIN SMALL LETTER B
+0061 1DF8 0300 05AE 1D16D 0062;00E0 1D16D 1DF8 05AE 0062;0061 1D16D 1DF8 05AE 0300 0062;00E0 1D16D 1DF8 05AE 0062;0061 1D16D 1DF8 05AE 0300 0062; # (a◌᷸◌̀◌𝅭֮b; à𝅭◌᷸◌֮b; a𝅭◌᷸◌֮◌̀b; à𝅭◌᷸◌֮b; a𝅭◌᷸◌֮◌̀b; ) LATIN SMALL LETTER A, COMBINING DOT ABOVE LEFT, COMBINING GRAVE ACCENT, HEBREW ACCENT ZINOR, MUSICAL SYMBOL COMBINING AUGMENTATION DOT, LATIN SMALL LETTER B
+0061 059A 0316 302A 1DF9 0062;0061 302A 0316 1DF9 059A 0062;0061 302A 0316 1DF9 059A 0062;0061 302A 0316 1DF9 059A 0062;0061 302A 0316 1DF9 059A 0062; # (a◌֚◌̖◌〪◌᷹b; a◌〪◌̖◌᷹◌֚b; a◌〪◌̖◌᷹◌֚b; a◌〪◌̖◌᷹◌֚b; a◌〪◌̖◌᷹◌֚b; ) LATIN SMALL LETTER A, HEBREW ACCENT YETIV, COMBINING GRAVE ACCENT BELOW, IDEOGRAPHIC LEVEL TONE MARK, COMBINING WIDE INVERTED BRIDGE BELOW, LATIN SMALL LETTER B
+0061 1DF9 059A 0316 302A 0062;0061 302A 1DF9 0316 059A 0062;0061 302A 1DF9 0316 059A 0062;0061 302A 1DF9 0316 059A 0062;0061 302A 1DF9 0316 059A 0062; # (a◌᷹◌֚◌̖◌〪b; a◌〪◌᷹◌̖◌֚b; a◌〪◌᷹◌̖◌֚b; a◌〪◌᷹◌̖◌֚b; a◌〪◌᷹◌̖◌֚b; ) LATIN SMALL LETTER A, COMBINING WIDE INVERTED BRIDGE BELOW, HEBREW ACCENT YETIV, COMBINING GRAVE ACCENT BELOW, IDEOGRAPHIC LEVEL TONE MARK, LATIN SMALL LETTER B
 0061 0315 0300 05AE 1DFB 0062;00E0 05AE 1DFB 0315 0062;0061 05AE 0300 1DFB 0315 0062;00E0 05AE 1DFB 0315 0062;0061 05AE 0300 1DFB 0315 0062; # (a◌̕◌̀◌֮◌᷻b; à◌֮◌᷻◌̕b; a◌֮◌̀◌᷻◌̕b; à◌֮◌᷻◌̕b; a◌֮◌̀◌᷻◌̕b; ) LATIN SMALL LETTER A, COMBINING COMMA ABOVE RIGHT, COMBINING GRAVE ACCENT, HEBREW ACCENT ZINOR, COMBINING DELETION MARK, LATIN SMALL LETTER B
 0061 1DFB 0315 0300 05AE 0062;0061 05AE 1DFB 0300 0315 0062;0061 05AE 1DFB 0300 0315 0062;0061 05AE 1DFB 0300 0315 0062;0061 05AE 1DFB 0300 0315 0062; # (a◌᷻◌̕◌̀◌֮b; a◌֮◌᷻◌̀◌̕b; a◌֮◌᷻◌̀◌̕b; a◌֮◌᷻◌̀◌̕b; a◌֮◌᷻◌̀◌̕b; ) LATIN SMALL LETTER A, COMBINING DELETION MARK, COMBINING COMMA ABOVE RIGHT, COMBINING GRAVE ACCENT, HEBREW ACCENT ZINOR, LATIN SMALL LETTER B
 0061 035D 035C 0315 1DFC 0062;0061 0315 035C 1DFC 035D 0062;0061 0315 035C 1DFC 035D 0062;0061 0315 035C 1DFC 035D 0062;0061 0315 035C 1DFC 035D 0062; # (a◌͝◌͜◌̕◌᷼b; a◌̕◌͜◌᷼◌͝b; a◌̕◌͜◌᷼◌͝b; a◌̕◌͜◌᷼◌͝b; a◌̕◌͜◌᷼◌͝b; ) LATIN SMALL LETTER A, COMBINING DOUBLE BREVE, COMBINING DOUBLE BREVE BELOW, COMBINING COMMA ABOVE RIGHT, COMBINING DOUBLE INVERTED BREVE BELOW, LATIN SMALL LETTER B
@@ -18397,8 +18409,20 @@ FFEE;FFEE;FFEE;25CB;25CB; # (￮; ￮; ￮; ○; ○; ) HALFWIDTH WHITE CIRCLE
 0061 116B7 3099 093C 0334 0062;0061 0334 116B7 093C 3099 0062;0061 0334 116B7 093C 3099 0062;0061 0334 116B7 093C 3099 0062;0061 0334 116B7 093C 3099 0062; # (a◌𑚷◌゙◌़◌̴b; a◌̴◌𑚷◌़◌゙b; a◌̴◌𑚷◌़◌゙b; a◌̴◌𑚷◌़◌゙b; a◌̴◌𑚷◌़◌゙b; ) LATIN SMALL LETTER A, TAKRI SIGN NUKTA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, DEVANAGARI SIGN NUKTA, COMBINING TILDE OVERLAY, LATIN SMALL LETTER B
 0061 05B0 094D 3099 1172B 0062;0061 3099 094D 1172B 05B0 0062;0061 3099 094D 1172B 05B0 0062;0061 3099 094D 1172B 05B0 0062;0061 3099 094D 1172B 05B0 0062; # (a◌ְ◌्◌゙◌𑜫b; a◌゙◌्◌𑜫◌ְb; a◌゙◌्◌𑜫◌ְb; a◌゙◌्◌𑜫◌ְb; a◌゙◌्◌𑜫◌ְb; ) LATIN SMALL LETTER A, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, AHOM SIGN KILLER, LATIN SMALL LETTER B
 0061 1172B 05B0 094D 3099 0062;0061 3099 1172B 094D 05B0 0062;0061 3099 1172B 094D 05B0 0062;0061 3099 1172B 094D 05B0 0062;0061 3099 1172B 094D 05B0 0062; # (a◌𑜫◌ְ◌्◌゙b; a◌゙◌𑜫◌्◌ְb; a◌゙◌𑜫◌्◌ְb; a◌゙◌𑜫◌्◌ְb; a◌゙◌𑜫◌्◌ְb; ) LATIN SMALL LETTER A, AHOM SIGN KILLER, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, LATIN SMALL LETTER B
+0061 05B0 094D 3099 11A34 0062;0061 3099 094D 11A34 05B0 0062;0061 3099 094D 11A34 05B0 0062;0061 3099 094D 11A34 05B0 0062;0061 3099 094D 11A34 05B0 0062; # (a◌ְ◌्◌゙◌𑨴b; a◌゙◌्◌𑨴◌ְb; a◌゙◌्◌𑨴◌ְb; a◌゙◌्◌𑨴◌ְb; a◌゙◌्◌𑨴◌ְb; ) LATIN SMALL LETTER A, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, ZANABAZAR SQUARE SIGN VIRAMA, LATIN SMALL LETTER B
+0061 11A34 05B0 094D 3099 0062;0061 3099 11A34 094D 05B0 0062;0061 3099 11A34 094D 05B0 0062;0061 3099 11A34 094D 05B0 0062;0061 3099 11A34 094D 05B0 0062; # (a◌𑨴◌ְ◌्◌゙b; a◌゙◌𑨴◌्◌ְb; a◌゙◌𑨴◌्◌ְb; a◌゙◌𑨴◌्◌ְb; a◌゙◌𑨴◌्◌ְb; ) LATIN SMALL LETTER A, ZANABAZAR SQUARE SIGN VIRAMA, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, LATIN SMALL LETTER B
+0061 05B0 094D 3099 11A47 0062;0061 3099 094D 11A47 05B0 0062;0061 3099 094D 11A47 05B0 0062;0061 3099 094D 11A47 05B0 0062;0061 3099 094D 11A47 05B0 0062; # (a◌ְ◌्◌゙◌𑩇b; a◌゙◌्◌𑩇◌ְb; a◌゙◌्◌𑩇◌ְb; a◌゙◌्◌𑩇◌ְb; a◌゙◌्◌𑩇◌ְb; ) LATIN SMALL LETTER A, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, ZANABAZAR SQUARE SUBJOINER, LATIN SMALL LETTER B
+0061 11A47 05B0 094D 3099 0062;0061 3099 11A47 094D 05B0 0062;0061 3099 11A47 094D 05B0 0062;0061 3099 11A47 094D 05B0 0062;0061 3099 11A47 094D 05B0 0062; # (a◌𑩇◌ְ◌्◌゙b; a◌゙◌𑩇◌्◌ְb; a◌゙◌𑩇◌्◌ְb; a◌゙◌𑩇◌्◌ְb; a◌゙◌𑩇◌्◌ְb; ) LATIN SMALL LETTER A, ZANABAZAR SQUARE SUBJOINER, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, LATIN SMALL LETTER B
+0061 05B0 094D 3099 11A99 0062;0061 3099 094D 11A99 05B0 0062;0061 3099 094D 11A99 05B0 0062;0061 3099 094D 11A99 05B0 0062;0061 3099 094D 11A99 05B0 0062; # (a◌ְ◌्◌゙◌𑪙b; a◌゙◌्◌𑪙◌ְb; a◌゙◌्◌𑪙◌ְb; a◌゙◌्◌𑪙◌ְb; a◌゙◌्◌𑪙◌ְb; ) LATIN SMALL LETTER A, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, SOYOMBO SUBJOINER, LATIN SMALL LETTER B
+0061 11A99 05B0 094D 3099 0062;0061 3099 11A99 094D 05B0 0062;0061 3099 11A99 094D 05B0 0062;0061 3099 11A99 094D 05B0 0062;0061 3099 11A99 094D 05B0 0062; # (a◌𑪙◌ְ◌्◌゙b; a◌゙◌𑪙◌्◌ְb; a◌゙◌𑪙◌्◌ְb; a◌゙◌𑪙◌्◌ְb; a◌゙◌𑪙◌्◌ְb; ) LATIN SMALL LETTER A, SOYOMBO SUBJOINER, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, LATIN SMALL LETTER B
 0061 05B0 094D 3099 11C3F 0062;0061 3099 094D 11C3F 05B0 0062;0061 3099 094D 11C3F 05B0 0062;0061 3099 094D 11C3F 05B0 0062;0061 3099 094D 11C3F 05B0 0062; # (a◌ְ◌्◌゙◌𑰿b; a◌゙◌्◌𑰿◌ְb; a◌゙◌्◌𑰿◌ְb; a◌゙◌्◌𑰿◌ְb; a◌゙◌्◌𑰿◌ְb; ) LATIN SMALL LETTER A, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, BHAIKSUKI SIGN VIRAMA, LATIN SMALL LETTER B
 0061 11C3F 05B0 094D 3099 0062;0061 3099 11C3F 094D 05B0 0062;0061 3099 11C3F 094D 05B0 0062;0061 3099 11C3F 094D 05B0 0062;0061 3099 11C3F 094D 05B0 0062; # (a◌𑰿◌ְ◌्◌゙b; a◌゙◌𑰿◌्◌ְb; a◌゙◌𑰿◌्◌ְb; a◌゙◌𑰿◌्◌ְb; a◌゙◌𑰿◌्◌ְb; ) LATIN SMALL LETTER A, BHAIKSUKI SIGN VIRAMA, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, LATIN SMALL LETTER B
+0061 3099 093C 0334 11D42 0062;0061 0334 093C 11D42 3099 0062;0061 0334 093C 11D42 3099 0062;0061 0334 093C 11D42 3099 0062;0061 0334 093C 11D42 3099 0062; # (a◌゙◌़◌̴◌𑵂b; a◌̴◌़◌𑵂◌゙b; a◌̴◌़◌𑵂◌゙b; a◌̴◌़◌𑵂◌゙b; a◌̴◌़◌𑵂◌゙b; ) LATIN SMALL LETTER A, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, DEVANAGARI SIGN NUKTA, COMBINING TILDE OVERLAY, MASARAM GONDI SIGN NUKTA, LATIN SMALL LETTER B
+0061 11D42 3099 093C 0334 0062;0061 0334 11D42 093C 3099 0062;0061 0334 11D42 093C 3099 0062;0061 0334 11D42 093C 3099 0062;0061 0334 11D42 093C 3099 0062; # (a◌𑵂◌゙◌़◌̴b; a◌̴◌𑵂◌़◌゙b; a◌̴◌𑵂◌़◌゙b; a◌̴◌𑵂◌़◌゙b; a◌̴◌𑵂◌़◌゙b; ) LATIN SMALL LETTER A, MASARAM GONDI SIGN NUKTA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, DEVANAGARI SIGN NUKTA, COMBINING TILDE OVERLAY, LATIN SMALL LETTER B
+0061 05B0 094D 3099 11D44 0062;0061 3099 094D 11D44 05B0 0062;0061 3099 094D 11D44 05B0 0062;0061 3099 094D 11D44 05B0 0062;0061 3099 094D 11D44 05B0 0062; # (a◌ְ◌्◌゙◌𑵄b; a◌゙◌्◌𑵄◌ְb; a◌゙◌्◌𑵄◌ְb; a◌゙◌्◌𑵄◌ְb; a◌゙◌्◌𑵄◌ְb; ) LATIN SMALL LETTER A, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, MASARAM GONDI SIGN HALANTA, LATIN SMALL LETTER B
+0061 11D44 05B0 094D 3099 0062;0061 3099 11D44 094D 05B0 0062;0061 3099 11D44 094D 05B0 0062;0061 3099 11D44 094D 05B0 0062;0061 3099 11D44 094D 05B0 0062; # (a◌𑵄◌ְ◌्◌゙b; a◌゙◌𑵄◌्◌ְb; a◌゙◌𑵄◌्◌ְb; a◌゙◌𑵄◌्◌ְb; a◌゙◌𑵄◌्◌ְb; ) LATIN SMALL LETTER A, MASARAM GONDI SIGN HALANTA, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, LATIN SMALL LETTER B
+0061 05B0 094D 3099 11D45 0062;0061 3099 094D 11D45 05B0 0062;0061 3099 094D 11D45 05B0 0062;0061 3099 094D 11D45 05B0 0062;0061 3099 094D 11D45 05B0 0062; # (a◌ְ◌्◌゙◌𑵅b; a◌゙◌्◌𑵅◌ְb; a◌゙◌्◌𑵅◌ְb; a◌゙◌्◌𑵅◌ְb; a◌゙◌्◌𑵅◌ְb; ) LATIN SMALL LETTER A, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, MASARAM GONDI VIRAMA, LATIN SMALL LETTER B
+0061 11D45 05B0 094D 3099 0062;0061 3099 11D45 094D 05B0 0062;0061 3099 11D45 094D 05B0 0062;0061 3099 11D45 094D 05B0 0062;0061 3099 11D45 094D 05B0 0062; # (a◌𑵅◌ְ◌्◌゙b; a◌゙◌𑵅◌्◌ְb; a◌゙◌𑵅◌्◌ְb; a◌゙◌𑵅◌्◌ְb; a◌゙◌𑵅◌्◌ְb; ) LATIN SMALL LETTER A, MASARAM GONDI VIRAMA, HEBREW POINT SHEVA, DEVANAGARI SIGN VIRAMA, COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK, LATIN SMALL LETTER B
 0061 093C 0334 16AF0 0062;0061 0334 16AF0 093C 0062;0061 0334 16AF0 093C 0062;0061 0334 16AF0 093C 0062;0061 0334 16AF0 093C 0062; # (a◌़◌̴◌𖫰b; a◌̴◌𖫰◌़b; a◌̴◌𖫰◌़b; a◌̴◌𖫰◌़b; a◌̴◌𖫰◌़b; ) LATIN SMALL LETTER A, DEVANAGARI SIGN NUKTA, COMBINING TILDE OVERLAY, BASSA VAH COMBINING HIGH TONE, LATIN SMALL LETTER B
 0061 16AF0 093C 0334 0062;0061 16AF0 0334 093C 0062;0061 16AF0 0334 093C 0062;0061 16AF0 0334 093C 0062;0061 16AF0 0334 093C 0062; # (a◌𖫰◌़◌̴b; a◌𖫰◌̴◌़b; a◌𖫰◌̴◌़b; a◌𖫰◌̴◌़b; a◌𖫰◌̴◌़b; ) LATIN SMALL LETTER A, BASSA VAH COMBINING HIGH TONE, DEVANAGARI SIGN NUKTA, COMBINING TILDE OVERLAY, LATIN SMALL LETTER B
 0061 093C 0334 16AF1 0062;0061 0334 16AF1 093C 0062;0061 0334 16AF1 093C 0062;0061 0334 16AF1 093C 0062;0061 0334 16AF1 093C 0062; # (a◌़◌̴◌𖫱b; a◌̴◌𖫱◌़b; a◌̴◌𖫱◌़b; a◌̴◌𖫱◌़b; a◌̴◌𖫱◌़b; ) LATIN SMALL LETTER A, DEVANAGARI SIGN NUKTA, COMBINING TILDE OVERLAY, BASSA VAH COMBINING LOW TONE, LATIN SMALL LETTER B
diff --git a/lib/stdlib/test/uri_string_SUITE.erl b/lib/stdlib/test/uri_string_SUITE.erl
new file mode 100644
index 0000000000..fef356355c
--- /dev/null
+++ b/lib/stdlib/test/uri_string_SUITE.erl
@@ -0,0 +1,926 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2008-2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(uri_string_SUITE).
+
+-include_lib("common_test/include/ct.hrl").
+
+-export([all/0, suite/0,groups/0,
+         normalize/1,
+         parse_binary_fragment/1, parse_binary_host/1, parse_binary_host_ipv4/1,
+         parse_binary_host_ipv6/1,
+         parse_binary_path/1, parse_binary_pct_encoded_fragment/1, parse_binary_pct_encoded_query/1,
+         parse_binary_pct_encoded_userinfo/1, parse_binary_port/1,
+         parse_binary_query/1, parse_binary_scheme/1, parse_binary_userinfo/1,
+         parse_fragment/1, parse_host/1, parse_host_ipv4/1, parse_host_ipv6/1,
+         parse_path/1, parse_pct_encoded_fragment/1, parse_pct_encoded_query/1,
+         parse_pct_encoded_userinfo/1, parse_port/1,
+         parse_query/1, parse_scheme/1, parse_userinfo/1,
+	 parse_list/1, parse_binary/1, parse_mixed/1, parse_relative/1,
+         parse_special/1, parse_special2/1, parse_negative/1,
+         recompose_fragment/1, recompose_parse_fragment/1,
+         recompose_query/1, recompose_parse_query/1,
+         recompose_path/1, recompose_parse_path/1,
+         recompose_autogen/1, parse_recompose_autogen/1,
+         transcode_basic/1, transcode_options/1, transcode_mixed/1, transcode_negative/1,
+         compose_query/1, compose_query_latin1/1, compose_query_negative/1,
+         dissect_query/1, dissect_query_negative/1,
+         interop_query_latin1/1, interop_query_utf8/1
+        ]).
+
+
+-define(SCHEME, "foo").
+-define(USERINFO, "åsa").
+-define(USERINFO_ENC, "%C3%A5sa").
+-define(HOST, "älvsjö").
+-define(HOST_ENC, "%C3%A4lvsj%C3%B6").
+-define(IPV6, "::127.0.0.1").
+-define(IPV6_ENC, "[::127.0.0.1]").
+-define(PORT, 8042).
+-define(PORT_ENC, ":8042").
+-define(PATH, "/där").
+-define(PATH_ENC, "/d%C3%A4r").
+-define(QUERY, "name=örn").
+-define(QUERY_ENC, "?name=%C3%B6rn").
+-define(FRAGMENT, "näsa").
+-define(FRAGMENT_ENC, "#n%C3%A4sa").
+
+
+suite() ->
+    [{timetrap,{minutes,1}}].
+
+all() ->
+    [
+     normalize,
+     parse_binary_scheme,
+     parse_binary_userinfo,
+     parse_binary_pct_encoded_userinfo,
+     parse_binary_host,
+     parse_binary_host_ipv4,
+     parse_binary_host_ipv6,
+     parse_binary_port,
+     parse_binary_path,
+     parse_binary_query,
+     parse_binary_pct_encoded_query,
+     parse_binary_fragment,
+     parse_binary_pct_encoded_fragment,
+     parse_scheme,
+     parse_userinfo,
+     parse_pct_encoded_userinfo,
+     parse_host,
+     parse_host_ipv4,
+     parse_host_ipv6,
+     parse_port,
+     parse_path,
+     parse_query,
+     parse_pct_encoded_query,
+     parse_fragment,
+     parse_pct_encoded_fragment,
+     parse_list,
+     parse_binary,
+     parse_mixed,
+     parse_relative,
+     parse_special,
+     parse_special2,
+     parse_negative,
+     recompose_fragment,
+     recompose_parse_fragment,
+     recompose_query,
+     recompose_parse_query,
+     recompose_path,
+     recompose_parse_path,
+     recompose_autogen,
+     parse_recompose_autogen,
+     transcode_basic,
+     transcode_options,
+     transcode_mixed,
+     transcode_negative,
+     compose_query,
+     compose_query_latin1,
+     compose_query_negative,
+     dissect_query,
+     dissect_query_negative,
+     interop_query_latin1,
+     interop_query_utf8
+    ].
+
+groups() ->
+    [].
+
+
+%%-------------------------------------------------------------------------
+%% Helper functions
+%%-------------------------------------------------------------------------
+uri_combinations() ->
+    [[Sch,Usr,Hst,Prt,Pat,Qry,Frg] ||
+        Sch <- [fun update_scheme/1, fun update_scheme_binary/1, none],
+        Usr <- [fun update_userinfo/1, fun update_userinfo_binary/1, none],
+        Hst <- [fun update_host/1, fun update_host_binary/1,
+                fun update_ipv6/1, fun update_ipv6_binary/1, none],
+        Prt <- [fun update_port/1, none],
+        Pat <- [fun update_path/1, fun update_path_binary/1],
+        Qry <- [fun update_query/1,fun update_query_binary/1, none],
+        Frg <- [fun update_fragment/1, fun update_fragment_binary/1, none],
+        not (Usr =:= none andalso Hst =:= none andalso Prt =/= none),
+        not (Usr =/= none andalso Hst =:= none andalso Prt =:= none),
+        not (Usr =/= none andalso Hst =:= none andalso Prt =/= none)].
+
+
+generate_test_vector(Comb) ->
+    Fun = fun (F, {Map, URI}) when is_function(F) -> F({Map, URI});
+              (_, Map) -> Map
+          end,
+    lists:foldl(Fun, {#{}, empty}, Comb).
+
+generate_test_vectors(L) ->
+    lists:map(fun generate_test_vector/1, L).
+
+update_fragment({In, empty}) ->
+    {In#{fragment => ?FRAGMENT}, ?FRAGMENT_ENC};
+update_fragment({In, Out}) when is_list(Out) ->
+    {In#{fragment => ?FRAGMENT}, Out ++ ?FRAGMENT_ENC};
+update_fragment({In, Out}) when is_binary(Out) ->
+    {In#{fragment => ?FRAGMENT}, binary_to_list(Out) ++ ?FRAGMENT_ENC}.
+
+update_fragment_binary({In, empty}) ->
+    {In#{fragment => <<?FRAGMENT/utf8>>}, <<?FRAGMENT_ENC>>};
+update_fragment_binary({In, Out}) when is_list(Out) ->
+    {In#{fragment => <<?FRAGMENT/utf8>>}, Out ++ ?FRAGMENT_ENC};
+update_fragment_binary({In, Out}) when is_binary(Out) ->
+    {In#{fragment => <<?FRAGMENT/utf8>>}, <<Out/binary,?FRAGMENT_ENC>>}.
+
+
+update_query({In, empty}) ->
+    {In#{query => ?QUERY}, ?QUERY_ENC};
+update_query({In, Out}) when is_list(Out) ->
+    {In#{query => ?QUERY}, Out ++ ?QUERY_ENC};
+update_query({In, Out}) when is_binary(Out) ->
+    {In#{query => ?QUERY}, binary_to_list(Out) ++ ?QUERY_ENC}.
+
+update_query_binary({In, empty}) ->
+    {In#{query => <<?QUERY/utf8>>}, <<?QUERY_ENC>>};
+update_query_binary({In, Out}) when is_list(Out) ->
+    {In#{query => <<?QUERY/utf8>>}, Out ++ ?QUERY_ENC};
+update_query_binary({In, Out}) when is_binary(Out) ->
+    {In#{query => <<?QUERY/utf8>>}, <<Out/binary,?QUERY_ENC>>}.
+
+update_path({In, empty}) ->
+    {In#{path => ?PATH}, ?PATH_ENC};
+update_path({In, Out}) when is_list(Out) ->
+    {In#{path => ?PATH}, Out ++ ?PATH_ENC};
+update_path({In, Out}) when is_binary(Out) ->
+    {In#{path => ?PATH}, binary_to_list(Out) ++ ?PATH_ENC}.
+
+update_path_binary({In, empty}) ->
+    {In#{path => <<?PATH/utf8>>}, <<?PATH_ENC>>};
+update_path_binary({In, Out}) when is_list(Out) ->
+    {In#{path => <<?PATH/utf8>>}, Out ++ ?PATH_ENC};
+update_path_binary({In, Out}) when is_binary(Out) ->
+    {In#{path => <<?PATH/utf8>>}, <<Out/binary,?PATH_ENC>>}.
+
+update_port({In, Out}) when is_list(Out) ->
+    {In#{port => ?PORT}, Out ++ ?PORT_ENC};
+update_port({In, Out}) when is_binary(Out) ->
+    {In#{port => ?PORT}, <<Out/binary,?PORT_ENC>>}.
+
+update_host({In, empty}) ->
+    {In#{host => ?HOST}, "//" ++ ?HOST_ENC};
+update_host({In, Out}) when is_list(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => ?HOST}, Out ++ [$@|?HOST_ENC]};
+        false -> {In#{host => ?HOST}, Out ++ [$/,$/|?HOST_ENC]}
+    end;
+update_host({In, Out}) when is_binary(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => ?HOST}, binary_to_list(Out) ++ [$@|?HOST_ENC]};
+        false -> {In#{host => ?HOST}, binary_to_list(Out) ++ [$/,$/|?HOST_ENC]}
+    end.
+
+update_host_binary({In, empty}) ->
+    {In#{host => <<?HOST/utf8>>}, <<"//",?HOST_ENC>>};
+update_host_binary({In, Out}) when is_list(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => <<?HOST/utf8>>}, Out ++ [$@|?HOST_ENC]};
+        false -> {In#{host => <<?HOST/utf8>>}, Out ++ [$/,$/|?HOST_ENC]}
+    end;
+update_host_binary({In, Out}) when is_binary(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => <<?HOST/utf8>>}, <<Out/binary,$@,?HOST_ENC>>};
+        false-> {In#{host => <<?HOST/utf8>>}, <<Out/binary,"//",?HOST_ENC>>}
+    end.
+
+update_ipv6({In, empty}) ->
+    {In#{host => ?IPV6}, "//" ++ ?IPV6_ENC};
+update_ipv6({In, Out}) when is_list(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => ?IPV6}, Out ++ [$@|?IPV6_ENC]};
+        false -> {In#{host => ?IPV6}, Out ++ [$/,$/|?IPV6_ENC]}
+    end;
+update_ipv6({In, Out}) when is_binary(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => ?IPV6}, binary_to_list(Out) ++ [$@|?IPV6_ENC]};
+        false -> {In#{host => ?IPV6}, binary_to_list(Out) ++ [$/,$/|?IPV6_ENC]}
+    end.
+
+update_ipv6_binary({In, empty}) ->
+    {In#{host => <<?IPV6/utf8>>}, <<"//",?IPV6_ENC>>};
+update_ipv6_binary({In, Out}) when is_list(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => <<?IPV6/utf8>>}, Out ++ [$@|?IPV6_ENC]};
+        false -> {In#{host => <<?IPV6/utf8>>}, Out ++ [$/,$/|?IPV6_ENC]}
+    end;
+update_ipv6_binary({In, Out}) when is_binary(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => <<?IPV6/utf8>>}, <<Out/binary,$@,?IPV6_ENC>>};
+        false-> {In#{host => <<?IPV6/utf8>>}, <<Out/binary,"//",?IPV6_ENC>>}
+    end.
+
+update_userinfo({In, empty}) ->
+    {In#{userinfo => ?USERINFO}, "//" ++ ?USERINFO_ENC};
+update_userinfo({In, Out}) when is_list(Out) ->
+    {In#{userinfo => ?USERINFO}, Out ++ "//" ++ ?USERINFO_ENC};
+update_userinfo({In, Out}) when is_binary(Out) ->
+    {In#{userinfo => ?USERINFO}, binary_to_list(Out) ++ "//" ++ ?USERINFO_ENC}.
+
+update_userinfo_binary({In, empty}) ->
+    {In#{userinfo => <<?USERINFO/utf8>>}, <<"//",?USERINFO_ENC>>};
+update_userinfo_binary({In, Out}) when is_list(Out) ->
+    {In#{userinfo => <<?USERINFO/utf8>>}, Out ++ "//" ++ ?USERINFO_ENC};
+update_userinfo_binary({In, Out}) when is_binary(Out) ->
+    {In#{userinfo => <<?USERINFO/utf8>>}, <<Out/binary,"//",?USERINFO_ENC>>}.
+
+update_scheme({In, empty}) ->
+    {In#{scheme => ?SCHEME}, ?SCHEME ++ ":"}.
+
+update_scheme_binary({In, empty}) ->
+    {In#{scheme => <<?SCHEME/utf8>>}, <<?SCHEME,$:>>}.
+
+
+%% Test recompose on a generated test vector
+run_test_recompose({#{}, empty}) ->
+    try "" = uri_string:recompose(#{}) of
+        _ -> ok
+    catch
+        _:_ -> error({test_failed, #{}, ""})
+    end;
+run_test_recompose({Map, URI}) ->
+    try URI = uri_string:recompose(Map) of
+        URI -> ok
+    catch
+        _:_ -> error({test_failed, Map, URI})
+    end.
+
+%% Test parse - recompose on a generated test vector
+run_test_parse_recompose({#{}, empty}) ->
+    try "" = uri_string:recompose(uri_string:parse("")) of
+        _ -> ok
+    catch
+        _:_ -> error({test_failed, #{}, ""})
+    end;
+run_test_parse_recompose({Map, URI}) ->
+    try URI = uri_string:recompose(uri_string:parse(URI)) of
+        URI -> ok
+    catch
+        _:_ -> error({test_failed, Map, URI})
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% Parse tests
+%%-------------------------------------------------------------------------
+
+parse_binary_scheme(_Config) ->
+    #{} = uri_string:parse(<<>>),
+    #{path := <<"foo">>} = uri_string:parse(<<"foo">>),
+    #{scheme := <<"foo">>} = uri_string:parse(<<"foo:">>),
+    #{scheme := <<"foo">>, path := <<"bar:nisse">>} = uri_string:parse(<<"foo:bar:nisse">>),
+    #{scheme := <<"foo">>, host := <<"">>} = uri_string:parse(<<"foo://">>),
+    #{scheme := <<"foo">>, host := <<"">>, path := <<"/">>} = uri_string:parse(<<"foo:///">>),
+    #{scheme := <<"foo">>, host := <<"">>, path := <<"//">>} = uri_string:parse(<<"foo:////">>),
+
+    #{path := <<"/">>} = uri_string:parse(<<"/">>),
+    #{host := <<>>} = uri_string:parse(<<"//">>),
+    #{host := <<>>, path := <<"/">>} = uri_string:parse(<<"///">>).
+
+parse_binary_userinfo(_Config) ->
+    #{scheme := <<"user">>, path := <<"password@localhost">>} =
+        uri_string:parse(<<"user:password@localhost">>),
+    #{path := <<"user@">>} = uri_string:parse(<<"user@">>),
+    #{path := <<"/user@">>} = uri_string:parse(<<"/user@">>),
+    #{path := <<"user@localhost">>} = uri_string:parse(<<"user@localhost">>),
+    #{userinfo := <<"user">>, host := <<"localhost">>} = uri_string:parse(<<"//user@localhost">>),
+    #{userinfo := <<"user:password">>, host := <<"localhost">>} =
+        uri_string:parse(<<"//user:password@localhost">>),
+    #{scheme := <<"foo">>, path := <<"/user@">>} =
+        uri_string:parse(<<"foo:/user@">>),
+    #{scheme := <<"foo">>, userinfo := <<"user">>, host := <<"localhost">>} =
+        uri_string:parse(<<"foo://user@localhost">>),
+    #{scheme := <<"foo">>, userinfo := <<"user:password">>, host := <<"localhost">>} =
+        uri_string:parse(<<"foo://user:password@localhost">>).
+
+parse_binary_pct_encoded_userinfo(_Config) ->
+    #{scheme := <<"user">>, path := <<"合@気道"/utf8>>} =
+        uri_string:parse(<<"user:%E5%90%88@%E6%B0%97%E9%81%93">>),
+    #{path := <<"合気道@"/utf8>>} = uri_string:parse(<<"%E5%90%88%E6%B0%97%E9%81%93@">>),
+    #{path := <<"/合気道@"/utf8>>} = uri_string:parse(<<"/%E5%90%88%E6%B0%97%E9%81%93@">>),
+    #{path := <<"合@気道"/utf8>>} = uri_string:parse(<<"%E5%90%88@%E6%B0%97%E9%81%93">>),
+    #{userinfo := <<"合"/utf8>>, host := <<"気道"/utf8>>} =
+        uri_string:parse(<<"//%E5%90%88@%E6%B0%97%E9%81%93">>),
+    #{userinfo := <<"合:気"/utf8>>, host := <<"道"/utf8>>} =
+        uri_string:parse(<<"//%E5%90%88:%E6%B0%97@%E9%81%93">>),
+    #{scheme := <<"foo">>, path := <<"/合気道@"/utf8>>} =
+        uri_string:parse(<<"foo:/%E5%90%88%E6%B0%97%E9%81%93@">>),
+    #{scheme := <<"foo">>, userinfo := <<"合"/utf8>>, host := <<"気道"/utf8>>} =
+        uri_string:parse(<<"foo://%E5%90%88@%E6%B0%97%E9%81%93">>),
+    #{scheme := <<"foo">>, userinfo := <<"合:気"/utf8>>, host := <<"道"/utf8>>} =
+        uri_string:parse(<<"foo://%E5%90%88:%E6%B0%97@%E9%81%93">>),
+    {error,invalid_uri,"@"} = uri_string:parse(<<"//%E5%90%88@%E6%B0%97%E9%81%93@">>),
+    {error,invalid_uri,":"} = uri_string:parse(<<"foo://%E5%90%88@%E6%B0%97%E9%81%93@">>).
+
+parse_binary_host(_Config) ->
+    #{host := <<"hostname">>} = uri_string:parse(<<"//hostname">>),
+    #{host := <<"hostname">>,scheme := <<"foo">>} = uri_string:parse(<<"foo://hostname">>),
+    #{host := <<"hostname">>,scheme := <<"foo">>, userinfo := <<"user">>} =
+        uri_string:parse(<<"foo://user@hostname">>).
+
+parse_binary_host_ipv4(_Config) ->
+    #{host := <<"127.0.0.1">>} = uri_string:parse(<<"//127.0.0.1">>),
+    #{host := <<"127.0.0.1">>, path := <<"/over/there">>} =
+        uri_string:parse(<<"//127.0.0.1/over/there">>),
+    #{host := <<"127.0.0.1">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"//127.0.0.1?name=ferret">>),
+    #{host := <<"127.0.0.1">>, fragment := <<"nose">>} = uri_string:parse(<<"//127.0.0.1#nose">>),
+    {error,invalid_uri,"x"} = uri_string:parse(<<"//127.0.0.x">>),
+    {error,invalid_uri,"1227.0.0.1"} = uri_string:parse(<<"//1227.0.0.1">>).
+
+parse_binary_host_ipv6(_Config) ->
+    #{host := <<"::127.0.0.1">>} = uri_string:parse(<<"//[::127.0.0.1]">>),
+    #{host := <<"2001:0db8:0000:0000:0000:0000:1428:07ab">>} =
+        uri_string:parse(<<"//[2001:0db8:0000:0000:0000:0000:1428:07ab]">>),
+    #{host := <<"::127.0.0.1">>, path := <<"/over/there">>} =
+        uri_string:parse(<<"//[::127.0.0.1]/over/there">>),
+    #{host := <<"::127.0.0.1">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"//[::127.0.0.1]?name=ferret">>),
+    #{host := <<"::127.0.0.1">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"//[::127.0.0.1]#nose">>),
+    {error,invalid_uri,"x"} = uri_string:parse(<<"//[::127.0.0.x]">>),
+    {error,invalid_uri,"::1227.0.0.1"} = uri_string:parse(<<"//[::1227.0.0.1]">>),
+    {error,invalid_uri,"G"} = uri_string:parse(<<"//[2001:0db8:0000:0000:0000:0000:1428:G7ab]">>).
+
+parse_binary_port(_Config) ->
+    #{path:= <<"/:8042">>} =
+        uri_string:parse(<<"/:8042">>),
+    #{host:= <<>>, port := 8042} =
+        uri_string:parse(<<"//:8042">>),
+    #{host := <<"example.com">>, port:= 8042} =
+        uri_string:parse(<<"//example.com:8042">>),
+    #{scheme := <<"foo">>, path := <<"/:8042">>} =
+        uri_string:parse(<<"foo:/:8042">>),
+    #{scheme := <<"foo">>, host := <<>>, port := 8042} =
+        uri_string:parse(<<"foo://:8042">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, port := 8042} =
+        uri_string:parse(<<"foo://example.com:8042">>),
+    {error,invalid_uri,":"} = uri_string:parse(":600"),
+    {error,invalid_uri,"x"} = uri_string:parse("//:8042x").
+
+parse_binary_path(_Config) ->
+    #{path := <<"over/there">>} = uri_string:parse(<<"over/there">>),
+    #{path := <<"/over/there">>} = uri_string:parse(<<"/over/there">>),
+    #{scheme := <<"foo">>, path := <<"/over/there">>} =
+        uri_string:parse(<<"foo:/over/there">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, path := <<"/over/there">>} =
+        uri_string:parse(<<"foo://example.com/over/there">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, path := <<"/over/there">>, port := 8042} =
+        uri_string:parse(<<"foo://example.com:8042/over/there">>).
+
+parse_binary_query(_Config) ->
+    #{scheme := <<"foo">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"foo:?name=ferret">>),
+    #{scheme := <<"foo">>, path:= <<"over/there">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"foo:over/there?name=ferret">>),
+    #{scheme := <<"foo">>, path:= <<"/over/there">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"foo:/over/there?name=ferret">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"foo://example.com?name=ferret">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, path := <<"/">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"foo://example.com/?name=ferret">>),
+
+    #{path := <<>>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"?name=ferret">>),
+    #{path := <<"over/there">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"over/there?name=ferret">>),
+    #{path := <<"/">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"/?name=ferret">>),
+    #{path := <<"/over/there">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"/over/there?name=ferret">>),
+    #{host := <<"example.com">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"//example.com?name=ferret">>),
+    #{host := <<"example.com">>, path := <<"/">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"//example.com/?name=ferret">>).
+
+parse_binary_pct_encoded_query(_Config) ->
+    #{scheme := <<"foo">>, host := <<"example.com">>, path := <<"/">>,
+      query := <<"name=合気道"/utf8>>} =
+        uri_string:parse(<<"foo://example.com/?name=%E5%90%88%E6%B0%97%E9%81%93">>),
+    #{host := <<"example.com">>, path := <<"/">>, query := <<"name=合気道"/utf8>>} =
+        uri_string:parse(<<"//example.com/?name=%E5%90%88%E6%B0%97%E9%81%93">>).
+
+parse_binary_fragment(_Config) ->
+    #{scheme := <<"foo">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo:#nose">>),
+    #{scheme := <<"foo">>, path:= <<"over/there">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo:over/there#nose">>),
+    #{scheme := <<"foo">>, path:= <<"/over/there">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo:/over/there#nose">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo://example.com#nose">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, path := <<"/">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo://example.com/#nose">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo://example.com#nose">>),
+
+    #{fragment := <<"nose">>} =
+        uri_string:parse(<<"#nose">>),
+    #{path := <<"over/there">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"over/there#nose">>),
+    #{path := <<"/">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"/#nose">>),
+    #{path := <<"/over/there">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"/over/there#nose">>),
+    #{host := <<"example.com">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"//example.com#nose">>),
+    #{host := <<"example.com">>, path := <<"/">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"//example.com/#nose">>).
+
+parse_binary_pct_encoded_fragment(_Config) ->
+    #{scheme := <<"foo">>, host := <<"example.com">>, fragment := <<"合気道"/utf8>>} =
+        uri_string:parse(<<"foo://example.com#%E5%90%88%E6%B0%97%E9%81%93">>),
+    #{host := <<"example.com">>, path := <<"/">>, fragment := <<"合気道"/utf8>>} =
+        uri_string:parse(<<"//example.com/#%E5%90%88%E6%B0%97%E9%81%93">>).
+
+parse_scheme(_Config) ->
+    #{} = uri_string:parse(""),
+    #{path := "foo"} = uri_string:parse("foo"),
+    #{scheme := "foo"} = uri_string:parse("foo:"),
+    #{scheme := "foo", path := "bar:nisse"} = uri_string:parse("foo:bar:nisse"),
+    #{scheme := "foo", host := ""} = uri_string:parse("foo://"),
+    #{scheme := "foo", host := "", path := "/"} = uri_string:parse("foo:///"),
+    #{scheme := "foo", host := "", path := "//"} = uri_string:parse("foo:////"),
+
+    #{path := "/"} = uri_string:parse("/"),
+    #{host := ""} = uri_string:parse("//"),
+    #{host := "", path := "/"} = uri_string:parse("///").
+
+parse_userinfo(_Config) ->
+    #{scheme := "user", path := "password@localhost"} = uri_string:parse("user:password@localhost"),
+    #{path := "user@"} = uri_string:parse("user@"),
+    #{path := "/user@"} = uri_string:parse("/user@"),
+    #{path := "user@localhost"} = uri_string:parse("user@localhost"),
+    #{userinfo := "user", host := "localhost"} = uri_string:parse("//user@localhost"),
+    #{userinfo := "user:password", host := "localhost"} =
+        uri_string:parse("//user:password@localhost"),
+    #{scheme := "foo", path := "/user@"} =
+        uri_string:parse("foo:/user@"),
+    #{scheme := "foo", userinfo := "user", host := "localhost"} =
+        uri_string:parse("foo://user@localhost"),
+    #{scheme := "foo", userinfo := "user:password", host := "localhost"} =
+        uri_string:parse("foo://user:password@localhost").
+
+parse_pct_encoded_userinfo(_Config) ->
+    #{scheme := "user", path := "合@気道"} =
+        uri_string:parse("user:%E5%90%88@%E6%B0%97%E9%81%93"),
+    #{path := "合気道@"} = uri_string:parse("%E5%90%88%E6%B0%97%E9%81%93@"),
+    #{path := "/合気道@"} = uri_string:parse("/%E5%90%88%E6%B0%97%E9%81%93@"),
+    #{path := "合@気道"} = uri_string:parse("%E5%90%88@%E6%B0%97%E9%81%93"),
+    #{userinfo := "合", host := "気道"} =
+        uri_string:parse("//%E5%90%88@%E6%B0%97%E9%81%93"),
+    #{userinfo := "合:気", host := "道"} =
+        uri_string:parse("//%E5%90%88:%E6%B0%97@%E9%81%93"),
+    #{scheme := "foo", path := "/合気道@"} =
+        uri_string:parse("foo:/%E5%90%88%E6%B0%97%E9%81%93@"),
+    #{scheme := "foo", userinfo := "合", host := "気道"} =
+        uri_string:parse("foo://%E5%90%88@%E6%B0%97%E9%81%93"),
+    #{scheme := "foo", userinfo := "合:気", host := "道"} =
+        uri_string:parse("foo://%E5%90%88:%E6%B0%97@%E9%81%93"),
+    {error,invalid_uri,"@"} = uri_string:parse("//%E5%90%88@%E6%B0%97%E9%81%93@"),
+    {error,invalid_uri,":"} = uri_string:parse("foo://%E5%90%88@%E6%B0%97%E9%81%93@").
+
+
+parse_host(_Config) ->
+    #{host := "hostname"} = uri_string:parse("//hostname"),
+    #{host := "hostname",scheme := "foo"} = uri_string:parse("foo://hostname"),
+    #{host := "hostname",scheme := "foo", userinfo := "user"} =
+        uri_string:parse("foo://user@hostname").
+
+parse_host_ipv4(_Config) ->
+    #{host := "127.0.0.1"} = uri_string:parse("//127.0.0.1"),
+    #{host := "2001:0db8:0000:0000:0000:0000:1428:07ab"} =
+        uri_string:parse("//[2001:0db8:0000:0000:0000:0000:1428:07ab]"),
+    #{host := "127.0.0.1", path := "/over/there"} = uri_string:parse("//127.0.0.1/over/there"),
+    #{host := "127.0.0.1", query := "name=ferret"} = uri_string:parse("//127.0.0.1?name=ferret"),
+    #{host := "127.0.0.1", fragment := "nose"} = uri_string:parse("//127.0.0.1#nose"),
+    {error,invalid_uri,"x"} = uri_string:parse("//127.0.0.x"),
+    {error,invalid_uri,"1227.0.0.1"} = uri_string:parse("//1227.0.0.1").
+
+parse_host_ipv6(_Config) ->
+    #{host := "::127.0.0.1"} = uri_string:parse("//[::127.0.0.1]"),
+    #{host := "::127.0.0.1", path := "/over/there"} = uri_string:parse("//[::127.0.0.1]/over/there"),
+    #{host := "::127.0.0.1", query := "name=ferret"} =
+        uri_string:parse("//[::127.0.0.1]?name=ferret"),
+    #{host := "::127.0.0.1", fragment := "nose"} = uri_string:parse("//[::127.0.0.1]#nose"),
+    {error,invalid_uri,"x"} = uri_string:parse("//[::127.0.0.x]"),
+    {error,invalid_uri,"::1227.0.0.1"} = uri_string:parse("//[::1227.0.0.1]"),
+    {error,invalid_uri,"G"} = uri_string:parse("//[2001:0db8:0000:0000:0000:0000:1428:G7ab]").
+
+parse_port(_Config) ->
+    #{path:= "/:8042"} =
+        uri_string:parse("/:8042"),
+    #{host:= "", port := 8042} =
+        uri_string:parse("//:8042"),
+    #{host := "example.com", port:= 8042} =
+        uri_string:parse("//example.com:8042"),
+    #{scheme := "foo", path := "/:8042"} =
+        uri_string:parse("foo:/:8042"),
+    #{scheme := "foo", host := "", port := 8042} =
+        uri_string:parse("foo://:8042"),
+    #{scheme := "foo", host := "example.com", port := 8042} =
+        uri_string:parse("foo://example.com:8042").
+
+parse_path(_Config) ->
+    #{path := "over/there"} = uri_string:parse("over/there"),
+    #{path := "/over/there"} = uri_string:parse("/over/there"),
+    #{scheme := "foo", path := "/over/there"} =
+        uri_string:parse("foo:/over/there"),
+    #{scheme := "foo", host := "example.com", path := "/over/there"} =
+        uri_string:parse("foo://example.com/over/there"),
+    #{scheme := "foo", host := "example.com", path := "/over/there", port := 8042} =
+        uri_string:parse("foo://example.com:8042/over/there").
+
+parse_query(_Config) ->
+    #{scheme := "foo", query := "name=ferret"} =
+        uri_string:parse("foo:?name=ferret"),
+    #{scheme := "foo", path:= "over/there", query := "name=ferret"} =
+        uri_string:parse("foo:over/there?name=ferret"),
+    #{scheme := "foo", path:= "/over/there", query := "name=ferret"} =
+        uri_string:parse("foo:/over/there?name=ferret"),
+    #{scheme := "foo", host := "example.com", query := "name=ferret"} =
+        uri_string:parse("foo://example.com?name=ferret"),
+    #{scheme := "foo", host := "example.com", path := "/", query := "name=ferret"} =
+        uri_string:parse("foo://example.com/?name=ferret"),
+
+    #{path := "", query := "name=ferret"} =
+        uri_string:parse("?name=ferret"),
+    #{path := "over/there", query := "name=ferret"} =
+        uri_string:parse("over/there?name=ferret"),
+    #{path := "/", query := "name=ferret"} =
+        uri_string:parse("/?name=ferret"),
+    #{path := "/over/there", query := "name=ferret"} =
+        uri_string:parse("/over/there?name=ferret"),
+    #{host := "example.com", query := "name=ferret"} =
+        uri_string:parse("//example.com?name=ferret"),
+    #{host := "example.com", path := "/", query := "name=ferret"} =
+        uri_string:parse("//example.com/?name=ferret").
+
+parse_pct_encoded_query(_Config) ->
+    #{scheme := "foo", host := "example.com", path := "/",
+      query := "name=合気道"} =
+        uri_string:parse("foo://example.com/?name=%E5%90%88%E6%B0%97%E9%81%93"),
+    #{host := "example.com", path := "/", query := "name=合気道"} =
+        uri_string:parse("//example.com/?name=%E5%90%88%E6%B0%97%E9%81%93").
+
+parse_fragment(_Config) ->
+    #{scheme := "foo", fragment := "nose"} =
+        uri_string:parse("foo:#nose"),
+    #{scheme := "foo", path:= "over/there", fragment := "nose"} =
+        uri_string:parse("foo:over/there#nose"),
+    #{scheme := "foo", path:= "/over/there", fragment := "nose"} =
+        uri_string:parse("foo:/over/there#nose"),
+    #{scheme := "foo", host := "example.com", fragment := "nose"} =
+        uri_string:parse("foo://example.com#nose"),
+    #{scheme := "foo", host := "example.com", path := "/", fragment := "nose"} =
+        uri_string:parse("foo://example.com/#nose"),
+    #{scheme := "foo", host := "example.com", fragment := "nose"} =
+        uri_string:parse("foo://example.com#nose"),
+
+    #{fragment := "nose"} =
+        uri_string:parse("#nose"),
+    #{path := "over/there", fragment := "nose"} =
+        uri_string:parse("over/there#nose"),
+    #{path := "/", fragment := "nose"} =
+        uri_string:parse("/#nose"),
+    #{path := "/over/there", fragment := "nose"} =
+        uri_string:parse("/over/there#nose"),
+    #{host := "example.com", fragment := "nose"} =
+        uri_string:parse("//example.com#nose"),
+    #{host := "example.com", path := "/", fragment := "nose"} =
+        uri_string:parse("//example.com/#nose").
+
+parse_pct_encoded_fragment(_Config) ->
+    #{scheme := "foo", host := "example.com", fragment := "合気道"} =
+        uri_string:parse("foo://example.com#%E5%90%88%E6%B0%97%E9%81%93"),
+    #{host := "example.com", path := "/", fragment := "合気道"} =
+        uri_string:parse("//example.com/#%E5%90%88%E6%B0%97%E9%81%93").
+
+parse_list(_Config) ->
+    #{scheme := "foo", path := "bar:nisse"} = uri_string:parse("foo:bar:nisse"),
+    #{scheme := "foo", host := "example.com", port := 8042,
+      path := "/over/there", query := "name=ferret", fragment := "nose"} =
+        uri_string:parse("foo://example.com:8042/over/there?name=ferret#nose"),
+    #{scheme := "foo", userinfo := "admin:admin", host := "example.com", port := 8042,
+      path := "/over/there", query := "name=ferret", fragment := "nose"} =
+        uri_string:parse("foo://admin:[email protected]:8042/over/there?name=ferret#nose").
+
+parse_binary(_Config) ->
+    #{scheme := <<"foo">>, path := <<"bar:nisse">>} = uri_string:parse(<<"foo:bar:nisse">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, port := 8042,
+      path := <<"/over/there">>, query := <<"name=ferret">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo://example.com:8042/over/there?name=ferret#nose">>),
+    #{scheme := <<"foo">>, userinfo := <<"admin:admin">>, host := <<"example.com">>, port := 8042,
+      path := <<"/over/there">>, query := <<"name=ferret">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo://admin:[email protected]:8042/over/there?name=ferret#nose">>).
+
+
+parse_mixed(_Config) ->
+    #{scheme := "foo", path := "bar"} =
+        uri_string:parse(lists:append("fo",<<"o:bar">>)),
+    #{scheme := "foo", path := "bar"} =
+        uri_string:parse(lists:append("foo:b",<<"ar">>)),
+    #{scheme := "foo", path := "bar:bar"} =
+        uri_string:parse([[102],[111,111],<<":bar">>,58,98,97,114]).
+
+parse_relative(_Config) ->
+    #{path := "/path"} =
+        uri_string:parse(lists:append("/pa",<<"th">>)),
+    #{path := "foo"} =
+        uri_string:parse(lists:append("fo",<<"o">>)).
+
+parse_special(_Config) ->
+    #{host := [],query := []} = uri_string:parse("//?"),
+    #{fragment := [],host := []} = uri_string:parse("//#"),
+    #{host := [],query := [],scheme := "foo"} = uri_string:parse("foo://?"),
+    #{fragment := [],host := [],scheme := "foo"} = uri_string:parse("foo://#"),
+    #{host := <<>>, path := <<"/">>} = uri_string:parse(<<"///">>),
+    #{host := <<"hostname">>} = uri_string:parse(<<"//hostname">>),
+    #{host := <<>>, path := <<"/hostname">>} = uri_string:parse(<<"///hostname">>),
+    #{host :=  [],path := "/",query := []} = uri_string:parse("///?"),
+    #{fragment := [],host := [],path := "/"} = uri_string:parse("///#"),
+    #{host := "foo",query := []} = uri_string:parse("//foo?"),
+    #{fragment := [],host := "foo"} = uri_string:parse("//foo#"),
+    #{host := "foo",path := "/"} = uri_string:parse("//foo/"),
+    #{host := "foo",query := [],scheme := "http"} = uri_string:parse("http://foo?"),
+    #{fragment := [],host := "foo",scheme := "http"} = uri_string:parse("http://foo#"),
+    #{host := "foo",path := "/",scheme := "http"} = uri_string:parse("http://foo/"),
+    #{fragment := [],host := "host",port := 80,scheme := "http"} = uri_string:parse("http://host:80#"),
+    #{host := "host",port := 80,query := [],scheme := "http"} = uri_string:parse("http://host:80?"),
+    #{path := [],query := []} = uri_string:parse("?"),
+    #{path := [],query := "?"} = uri_string:parse("??"),
+    #{path := [],query := "??"} = uri_string:parse("???").
+
+parse_special2(_Config) ->
+    #{host := [],path := "/",port := 1,scheme := "a"} = uri_string:parse("a://:1/"),
+    #{path := "/a/",scheme := "a"} = uri_string:parse("a:/a/"),
+    #{host := [],path := [],userinfo := []} = uri_string:parse("//@"),
+    #{host := [],path := [],scheme := "foo",userinfo := []} = uri_string:parse("foo://@"),
+    #{host := [],path := "/",userinfo := []} = uri_string:parse("//@/"),
+    #{host := [],path := "/",scheme := "foo",userinfo := []} = uri_string:parse("foo://@/"),
+    #{host := "localhost",path := "/",port := undefined} = uri_string:parse("//localhost:/"),
+    #{host := [],path := [],port := undefined} = uri_string:parse("//:").
+
+parse_negative(_Config) ->
+    {error,invalid_uri,"å"} = uri_string:parse("å"),
+    {error,invalid_uri,"å"} = uri_string:parse("aå:/foo"),
+    {error,invalid_uri,":"} = uri_string:parse("foo://usär@host"),
+    {error,invalid_uri,"ö"} = uri_string:parse("//host/path?foö=bar"),
+    {error,invalid_uri,"ö"} = uri_string:parse("//host/path#foö"),
+    {error,invalid_uri,"127.256.0.1"} = uri_string:parse("//127.256.0.1"),
+    {error,invalid_uri,":::127.0.0.1"} = uri_string:parse("//[:::127.0.0.1]"),
+    {error,invalid_utf8,<<0,0,0,246>>} = uri_string:parse("//%00%00%00%F6"),
+    {error,invalid_uri,"A"} = uri_string:parse("//localhost:A8").
+
+
+%%-------------------------------------------------------------------------
+%% Recompose tests
+%%-------------------------------------------------------------------------
+recompose_fragment(_Config) ->
+    <<?FRAGMENT_ENC>> = uri_string:recompose(#{fragment => <<?FRAGMENT/utf8>>, path => <<>>}),
+    ?FRAGMENT_ENC = uri_string:recompose(#{fragment => ?FRAGMENT, path => ""}).
+
+recompose_parse_fragment(_Config) ->
+    <<?FRAGMENT_ENC>> = uri_string:recompose(uri_string:parse(<<?FRAGMENT_ENC>>)),
+    ?FRAGMENT_ENC = uri_string:recompose(uri_string:parse(?FRAGMENT_ENC)).
+
+recompose_query(_Config) ->
+    <<?QUERY_ENC>> =
+        uri_string:recompose(#{query => <<?QUERY/utf8>>, path => <<>>}),
+    <<?QUERY_ENC?FRAGMENT_ENC>> =
+        uri_string:recompose(#{query => <<?QUERY/utf8>>,
+                               fragment => <<?FRAGMENT/utf8>>,
+                               path => <<>>}),
+    "?name=%C3%B6rn" =
+        uri_string:recompose(#{query => "name=örn", path => ""}),
+    "?name=%C3%B6rn#n%C3%A4sa" =
+        uri_string:recompose(#{query => "name=örn",
+                               fragment => "näsa",
+                               path => ""}).
+
+recompose_parse_query(_Config) ->
+    <<"?name=%C3%B6rn">> = uri_string:recompose(uri_string:parse(<<"?name=%C3%B6rn">>)),
+    <<"?name=%C3%B6rn#n%C3%A4sa">> =
+        uri_string:recompose(uri_string:parse(<<"?name=%C3%B6rn#n%C3%A4sa">>)),
+    "?name=%C3%B6rn" = uri_string:recompose(uri_string:parse("?name=%C3%B6rn")),
+    "?name=%C3%B6rn#n%C3%A4sa" = uri_string:recompose(uri_string:parse("?name=%C3%B6rn#n%C3%A4sa")).
+
+recompose_path(_Config) ->
+    <<"/d%C3%A4r">> =
+        uri_string:recompose(#{path => <<"/där"/utf8>>}),
+    <<"/d%C3%A4r#n%C3%A4sa">> =
+        uri_string:recompose(#{path => <<"/där"/utf8>>,
+                               fragment => <<"näsa"/utf8>>}),
+    <<"/d%C3%A4r?name=%C3%B6rn">> =
+        uri_string:recompose(#{path => <<"/där"/utf8>>,
+                               query => <<"name=örn"/utf8>>}),
+    <<"/d%C3%A4r?name=%C3%B6rn#n%C3%A4sa">> =
+        uri_string:recompose(#{path => <<"/där"/utf8>>,
+                               query => <<"name=örn"/utf8>>,
+                               fragment => <<"näsa"/utf8>>}),
+
+
+    "/d%C3%A4r" =
+        uri_string:recompose(#{path => "/där"}),
+    "/d%C3%A4r#n%C3%A4sa" =
+        uri_string:recompose(#{path => "/där",
+                               fragment => "näsa"}),
+    "/d%C3%A4r?name=%C3%B6rn" =
+        uri_string:recompose(#{path => "/där",
+                               query => "name=örn"}),
+    "/d%C3%A4r?name=%C3%B6rn#n%C3%A4sa" =
+        uri_string:recompose(#{path => "/där",
+                               query => "name=örn",
+                               fragment => "näsa"}).
+
+
+recompose_parse_path(_Config) ->
+    <<"/d%C3%A4r">> =
+        uri_string:recompose(uri_string:parse(<<"/d%C3%A4r">>)),
+    <<"/d%C3%A4r#n%C3%A4sa">> =
+        uri_string:recompose(uri_string:parse(<<"/d%C3%A4r#n%C3%A4sa">>)),
+    <<"/d%C3%A4r?name=%C3%B6rn">> =
+        uri_string:recompose(uri_string:parse(<<"/d%C3%A4r?name=%C3%B6rn">>)),
+
+    "/d%C3%A4r" =
+        uri_string:recompose(uri_string:parse("/d%C3%A4r")),
+    "/d%C3%A4r#n%C3%A4sa" =
+        uri_string:recompose(uri_string:parse("/d%C3%A4r#n%C3%A4sa")),
+    "/d%C3%A4r?name=%C3%B6rn" =
+        uri_string:recompose(uri_string:parse("/d%C3%A4r?name=%C3%B6rn")).
+
+
+recompose_autogen(_Config) ->
+    Tests = generate_test_vectors(uri_combinations()),
+    lists:map(fun run_test_recompose/1, Tests).
+
+parse_recompose_autogen(_Config) ->
+    Tests = generate_test_vectors(uri_combinations()),
+    lists:map(fun run_test_parse_recompose/1, Tests).
+
+transcode_basic(_Config) ->
+    <<"foo%C3%B6bar"/utf8>> =
+        uri_string:transcode(<<"foo%00%00%00%F6bar"/utf32>>, [{in_encoding, utf32},{out_encoding, utf8}]),
+    "foo%C3%B6bar" =
+        uri_string:transcode("foo%00%00%00%F6bar", [{in_encoding, utf32},{out_encoding, utf8}]),
+    <<"foo%00%00%00%F6bar"/utf32>> =
+        uri_string:transcode(<<"foo%C3%B6bar"/utf8>>, [{in_encoding, utf8},{out_encoding, utf32}]),
+    "foo%00%00%00%F6bar" =
+        uri_string:transcode("foo%C3%B6bar", [{in_encoding, utf8},{out_encoding, utf32}]),
+    "foo%C3%B6bar" =
+        uri_string:transcode("foo%F6bar", [{in_encoding, latin1},{out_encoding, utf8}]).
+
+transcode_options(_Config) ->
+    <<"foo%C3%B6bar"/utf8>> =
+        uri_string:transcode(<<"foo%C3%B6bar"/utf8>>, []),
+    <<"foo%C3%B6bar"/utf8>> =
+        uri_string:transcode(<<"foo%00%00%00%F6bar"/utf32>>, [{in_encoding, utf32}]),
+    <<"foo%00%00%00%F6bar"/utf32>> =
+        uri_string:transcode(<<"foo%C3%B6bar"/utf8>>, [{out_encoding, utf32}]).
+
+transcode_mixed(_Config) ->
+    "foo%00%00%00%F6bar" =
+        uri_string:transcode(["foo",<<"%C3%B6"/utf8>>,<<"ba"/utf8>>,"r"], [{out_encoding, utf32}]),
+    "foo%00%00%00%F6bar" =
+        uri_string:transcode(["foo",<<"%C3%"/utf8>>,<<"B6ba"/utf8>>,"r"], [{out_encoding, utf32}]),
+    "foo%C3%B6bar" =
+        uri_string:transcode(["foo%00", <<"%00%0"/utf32>>,<<"0%F"/utf32>>,"6bar"], [{in_encoding, utf32},{out_encoding, utf8}]).
+
+transcode_negative(_Config) ->
+    {error,invalid_percent_encoding,"%BXbar"} =
+        uri_string:transcode(<<"foo%C3%BXbar"/utf8>>, [{in_encoding, utf8},{out_encoding, utf32}]),
+    {error,invalid_input,<<"ö">>} =
+        uri_string:transcode("foo%F6bar", [{in_encoding, utf8},{out_encoding, utf8}]).
+
+compose_query(_Config) ->
+    [] = uri_string:compose_query([]),
+    "foo=1&bar=2" = uri_string:compose_query([{<<"foo">>,"1"}, {"bar", "2"}]),
+    "foo=1&b%C3%A4r=2" = uri_string:compose_query([{"foo","1"}, {"bär", "2"}],[{encoding,utf8}]),
+    "foo=1&b%C3%A4r=2" = uri_string:compose_query([{"foo","1"}, {"bär", "2"}],[{encoding,unicode}]),
+    "foo=1&b%E4r=2" = uri_string:compose_query([{"foo","1"}, {"bär", "2"}],[{encoding,latin1}]),
+    "foo+bar=1&%E5%90%88=2" = uri_string:compose_query([{"foo bar","1"}, {"合", "2"}]),
+    "foo+bar=1&%26%2321512%3B=2" =
+        uri_string:compose_query([{"foo bar","1"}, {"合", "2"}],[{encoding,latin1}]),
+    "foo+bar=1&%C3%B6=2" = uri_string:compose_query([{<<"foo bar">>,<<"1">>}, {"ö", <<"2">>}]),
+    <<"foo+bar=1&%C3%B6=2">> =
+        uri_string:compose_query([{<<"foo bar">>,<<"1">>}, {<<"ö"/utf8>>, <<"2">>}]).
+
+compose_query_latin1(_Config) ->
+    Q = uri_string:compose_query([{"合foö bar","1"}, {"合", "合"}],[{encoding,latin1}]),
+    Q1 = uri_string:transcode(Q, [{in_encoding, latin1}]),
+    [{"合foö bar","1"}, {"合", "合"}] = uri_string:dissect_query(Q1),
+    Q2 = uri_string:compose_query([{<<"合foö bar"/utf8>>,<<"1">>}, {<<"合"/utf8>>, <<"合"/utf8>>}],
+                                  [{encoding,latin1}]),
+    Q3 = uri_string:transcode(Q2, [{in_encoding, latin1}]),
+    [{<<"合foö bar"/utf8>>,<<"1">>}, {<<"合"/utf8>>, <<"合"/utf8>>}] =
+        uri_string:dissect_query(Q3).
+
+compose_query_negative(_Config) ->
+    {error,invalid_input,4} = uri_string:compose_query([{"",4}]),
+    {error,invalid_input,5} = uri_string:compose_query([{5,""}]),
+    {error,invalid_encoding,utf16} =
+        uri_string:compose_query([{"foo bar","1"}, {<<"ö">>, "2"}],[{encoding,utf16}]).
+
+dissect_query(_Config) ->
+    [] = uri_string:dissect_query(""),
+    [{"foo","1"}, {"amp;bar", "2"}] = uri_string:dissect_query("foo=1&amp;bar=2"),
+    [{"foo","1"}, {"bar", "2"}] = uri_string:dissect_query("foo=1&bar=2"),
+    [{"foo","1;bar=2"}] = uri_string:dissect_query("foo=1;bar=2"),
+    [{"foo","1"}, {"bar", "222"}] = uri_string:dissect_query([<<"foo=1&bar=2">>,"22"]),
+    [{"foo","ö"}, {"bar", "2"}] = uri_string:dissect_query("foo=%C3%B6&bar=2"),
+    [{<<"foo">>,<<"ö"/utf8>>}, {<<"bar">>, <<"2">>}] =
+        uri_string:dissect_query(<<"foo=%C3%B6&bar=2">>),
+    [{"foo bar","1"},{"ö","2"}] =
+        uri_string:dissect_query([<<"foo+bar=1&">>,<<"%C3%B6=2">>]),
+    [{"foo bar","1"},{[21512],"2"}] =
+        uri_string:dissect_query("foo+bar=1&%26%2321512%3B=2"),
+    [{<<"foo bar">>,<<"1">>},{<<"合"/utf8>>,<<"2">>}] =
+        uri_string:dissect_query(<<"foo+bar=1&%26%2321512%3B=2">>),
+    [{"föo bar","1"},{"ö","2"}] =
+        uri_string:dissect_query("föo+bar=1&%C3%B6=2"),
+    [{<<"föo bar"/utf8>>,<<"1">>},{<<"ö"/utf8>>,<<"2">>}] =
+        uri_string:dissect_query(<<"föo+bar=1&%C3%B6=2"/utf8>>).
+
+dissect_query_negative(_Config) ->
+    {error,missing_value,"&"} =
+        uri_string:dissect_query("foo1&bar=2"),
+    {error,invalid_percent_encoding,"%XX%B6"} = uri_string:dissect_query("foo=%XX%B6&amp;bar=2"),
+    {error,invalid_input,[153]} =
+        uri_string:dissect_query("foo=%99%B6&amp;bar=2"),
+    {error,invalid_character,"ö"} = uri_string:dissect_query(<<"föo+bar=1&%C3%B6=2">>),
+    {error,invalid_input,<<"ö">>} =
+        uri_string:dissect_query([<<"foo+bar=1&amp;">>,<<"%C3%B6=2ö">>]).
+
+normalize(_Config) ->
+    "/a/g" = uri_string:normalize("/a/b/c/./../../g"),
+    <<"mid/6">> = uri_string:normalize(<<"mid/content=5/../6">>),
+    "http://localhost-%C3%B6rebro/a/g" =
+        uri_string:normalize("http://localhos%74-%c3%b6rebro:80/a/b/c/./../../g"),
+    <<"http://localhost-%C3%B6rebro/a/g">> =
+        uri_string:normalize(<<"http://localhos%74-%c3%b6rebro:80/a/b/c/./../../g">>),
+    <<"https://localhost/">> =
+        uri_string:normalize(<<"https://localhost:443">>),
+    <<"https://localhost:445/">> =
+        uri_string:normalize(<<"https://localhost:445">>),
+    <<"ftp://localhost">> =
+        uri_string:normalize(<<"ftp://localhost:21">>),
+    <<"ssh://localhost">> =
+        uri_string:normalize(<<"ssh://localhost:22">>),
+    <<"sftp://localhost">> =
+        uri_string:normalize(<<"sftp://localhost:22">>),
+    <<"tftp://localhost">> =
+        uri_string:normalize(<<"tftp://localhost:69">>).
+
+interop_query_utf8(_Config) ->
+    Q = uri_string:compose_query([{"foo bar","1"}, {"合", "2"}]),
+    Uri = uri_string:recompose(#{path => "/", query => Q}),
+    #{query := Q1} = uri_string:parse(Uri),
+    [{"foo bar","1"}, {"合", "2"}] = uri_string:dissect_query(Q1).
+
+interop_query_latin1(_Config) ->
+    Q = uri_string:compose_query([{"foo bar","1"}, {"合", "2"}], [{encoding,latin1}]),
+    Uri = uri_string:recompose(#{path => "/", query => Q}),
+    Uri1 = uri_string:transcode(Uri, [{in_encoding, latin1}]),
+    #{query := Q1} = uri_string:parse(Uri1),
+    [{"foo bar","1"}, {"合", "2"}] = uri_string:dissect_query(Q1).
diff --git a/lib/stdlib/test/uri_string_property_test_SUITE.erl b/lib/stdlib/test/uri_string_property_test_SUITE.erl
new file mode 100644
index 0000000000..ae2c61c7aa
--- /dev/null
+++ b/lib/stdlib/test/uri_string_property_test_SUITE.erl
@@ -0,0 +1,39 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2008-2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(uri_string_property_test_SUITE).
+
+-include_lib("common_test/include/ct.hrl").
+-compile(export_all).
+
+all() -> [recompose].
+
+init_per_suite(Config) ->
+    ct_property_test:init_per_suite(Config).
+
+end_per_suite(Config) ->
+    Config.
+
+%%%========================================================================
+%%% Test suites
+%%%========================================================================
+recompose(Config) ->
+    ct_property_test:quickcheck(
+      uri_string_recompose:prop_recompose(),
+      Config).
diff --git a/lib/stdlib/uc_spec/CaseFolding.txt b/lib/stdlib/uc_spec/CaseFolding.txt
index 372ee68bd8..efdf18e441 100644
--- a/lib/stdlib/uc_spec/CaseFolding.txt
+++ b/lib/stdlib/uc_spec/CaseFolding.txt
@@ -1,6 +1,6 @@
-# CaseFolding-9.0.0.txt
-# Date: 2016-03-02, 18:54:54 GMT
-# © 2016 Unicode®, Inc.
+# CaseFolding-10.0.0.txt
+# Date: 2017-04-14, 05:40:18 GMT
+# © 2017 Unicode®, Inc.
 # Unicode and the Unicode Logo are registered trademarks of Unicode, Inc. in the U.S. and other countries.
 # For terms of use, see http://www.unicode.org/terms_of_use.html
 #
@@ -24,7 +24,7 @@
 #
 # NOTE: case folding does not preserve normalization formats!
 #
-# For information on case folding, including how to have case folding 
+# For information on case folding, including how to have case folding
 # preserve normalization formats, see Section 3.13 Default Case Algorithms in
 # The Unicode Standard.
 #
diff --git a/lib/stdlib/uc_spec/CompositionExclusions.txt b/lib/stdlib/uc_spec/CompositionExclusions.txt
index 1999ed1328..ff42508686 100644
--- a/lib/stdlib/uc_spec/CompositionExclusions.txt
+++ b/lib/stdlib/uc_spec/CompositionExclusions.txt
@@ -1,6 +1,6 @@
-# CompositionExclusions-9.0.0.txt
-# Date: 2016-01-21, 22:00:00 GMT [KW, LI]
-# © 2016 Unicode®, Inc.
+# CompositionExclusions-10.0.0.txt
+# Date: 2017-02-15, 00:00:00 GMT [KW, LI]
+# © 2017 Unicode®, Inc.
 # For terms of use, see http://www.unicode.org/terms_of_use.html
 #
 # Unicode Character Database
diff --git a/lib/stdlib/uc_spec/GraphemeBreakProperty.txt b/lib/stdlib/uc_spec/GraphemeBreakProperty.txt
index c5e94a3762..32bb12e47e 100644
--- a/lib/stdlib/uc_spec/GraphemeBreakProperty.txt
+++ b/lib/stdlib/uc_spec/GraphemeBreakProperty.txt
@@ -1,6 +1,6 @@
-# GraphemeBreakProperty-9.0.0.txt
-# Date: 2016-06-03, 22:23:55 GMT
-# © 2016 Unicode®, Inc.
+# GraphemeBreakProperty-10.0.0.txt
+# Date: 2017-03-12, 07:03:41 GMT
+# © 2017 Unicode®, Inc.
 # Unicode and the Unicode Logo are registered trademarks of Unicode, Inc. in the U.S. and other countries.
 # For terms of use, see http://www.unicode.org/terms_of_use.html
 #
@@ -25,8 +25,11 @@
 0D4E          ; Prepend # Lo       MALAYALAM LETTER DOT REPH
 110BD         ; Prepend # Cf       KAITHI NUMBER SIGN
 111C2..111C3  ; Prepend # Lo   [2] SHARADA SIGN JIHVAMULIYA..SHARADA SIGN UPADHMANIYA
+11A3A         ; Prepend # Lo       ZANABAZAR SQUARE CLUSTER-INITIAL LETTER RA
+11A86..11A89  ; Prepend # Lo   [4] SOYOMBO CLUSTER-INITIAL LETTER RA..SOYOMBO CLUSTER-INITIAL LETTER SA
+11D46         ; Prepend # Lo       MASARAM GONDI REPHA
 
-# Total code points: 13
+# Total code points: 19
 
 # ================================================
 
@@ -126,6 +129,7 @@ E01F0..E0FFF  ; Control # Cn [3600] <reserved-E01F0>..<reserved-E0FFF>
 0AC7..0AC8    ; Extend # Mn   [2] GUJARATI VOWEL SIGN E..GUJARATI VOWEL SIGN AI
 0ACD          ; Extend # Mn       GUJARATI SIGN VIRAMA
 0AE2..0AE3    ; Extend # Mn   [2] GUJARATI VOWEL SIGN VOCALIC L..GUJARATI VOWEL SIGN VOCALIC LL
+0AFA..0AFF    ; Extend # Mn   [6] GUJARATI SIGN SUKUN..GUJARATI SIGN TWO-CIRCLE NUKTA ABOVE
 0B01          ; Extend # Mn       ORIYA SIGN CANDRABINDU
 0B3C          ; Extend # Mn       ORIYA SIGN NUKTA
 0B3E          ; Extend # Mc       ORIYA VOWEL SIGN AA
@@ -154,7 +158,8 @@ E01F0..E0FFF  ; Control # Cn [3600] <reserved-E01F0>..<reserved-E0FFF>
 0CCC..0CCD    ; Extend # Mn   [2] KANNADA VOWEL SIGN AU..KANNADA SIGN VIRAMA
 0CD5..0CD6    ; Extend # Mc   [2] KANNADA LENGTH MARK..KANNADA AI LENGTH MARK
 0CE2..0CE3    ; Extend # Mn   [2] KANNADA VOWEL SIGN VOCALIC L..KANNADA VOWEL SIGN VOCALIC LL
-0D01          ; Extend # Mn       MALAYALAM SIGN CANDRABINDU
+0D00..0D01    ; Extend # Mn   [2] MALAYALAM SIGN COMBINING ANUSVARA ABOVE..MALAYALAM SIGN CANDRABINDU
+0D3B..0D3C    ; Extend # Mn   [2] MALAYALAM SIGN VERTICAL BAR VIRAMA..MALAYALAM SIGN CIRCULAR VIRAMA
 0D3E          ; Extend # Mc       MALAYALAM VOWEL SIGN AA
 0D41..0D44    ; Extend # Mn   [4] MALAYALAM VOWEL SIGN U..MALAYALAM VOWEL SIGN VOCALIC RR
 0D4D          ; Extend # Mn       MALAYALAM SIGN VIRAMA
@@ -243,7 +248,7 @@ E01F0..E0FFF  ; Control # Cn [3600] <reserved-E01F0>..<reserved-E0FFF>
 1CED          ; Extend # Mn       VEDIC SIGN TIRYAK
 1CF4          ; Extend # Mn       VEDIC TONE CANDRA ABOVE
 1CF8..1CF9    ; Extend # Mn   [2] VEDIC TONE RING ABOVE..VEDIC TONE DOUBLE RING ABOVE
-1DC0..1DF5    ; Extend # Mn  [54] COMBINING DOTTED GRAVE ACCENT..COMBINING UP TACK ABOVE
+1DC0..1DF9    ; Extend # Mn  [58] COMBINING DOTTED GRAVE ACCENT..COMBINING WIDE INVERTED BRIDGE BELOW
 1DFB..1DFF    ; Extend # Mn   [5] COMBINING DELETION MARK..COMBINING RIGHT ARROWHEAD AND DOWN ARROWHEAD BELOW
 200C          ; Extend # Cf       ZERO WIDTH NON-JOINER
 20D0..20DC    ; Extend # Mn  [13] COMBINING LEFT HARPOON ABOVE..COMBINING FOUR DOTS ABOVE
@@ -353,6 +358,15 @@ FF9E..FF9F    ; Extend # Lm   [2] HALFWIDTH KATAKANA VOICED SOUND MARK..HALFWIDT
 1171D..1171F  ; Extend # Mn   [3] AHOM CONSONANT SIGN MEDIAL LA..AHOM CONSONANT SIGN MEDIAL LIGATING RA
 11722..11725  ; Extend # Mn   [4] AHOM VOWEL SIGN I..AHOM VOWEL SIGN UU
 11727..1172B  ; Extend # Mn   [5] AHOM VOWEL SIGN AW..AHOM SIGN KILLER
+11A01..11A06  ; Extend # Mn   [6] ZANABAZAR SQUARE VOWEL SIGN I..ZANABAZAR SQUARE VOWEL SIGN O
+11A09..11A0A  ; Extend # Mn   [2] ZANABAZAR SQUARE VOWEL SIGN REVERSED I..ZANABAZAR SQUARE VOWEL LENGTH MARK
+11A33..11A38  ; Extend # Mn   [6] ZANABAZAR SQUARE FINAL CONSONANT MARK..ZANABAZAR SQUARE SIGN ANUSVARA
+11A3B..11A3E  ; Extend # Mn   [4] ZANABAZAR SQUARE CLUSTER-FINAL LETTER YA..ZANABAZAR SQUARE CLUSTER-FINAL LETTER VA
+11A47         ; Extend # Mn       ZANABAZAR SQUARE SUBJOINER
+11A51..11A56  ; Extend # Mn   [6] SOYOMBO VOWEL SIGN I..SOYOMBO VOWEL SIGN OE
+11A59..11A5B  ; Extend # Mn   [3] SOYOMBO VOWEL SIGN VOCALIC R..SOYOMBO VOWEL LENGTH MARK
+11A8A..11A96  ; Extend # Mn  [13] SOYOMBO FINAL CONSONANT SIGN G..SOYOMBO SIGN ANUSVARA
+11A98..11A99  ; Extend # Mn   [2] SOYOMBO GEMINATION MARK..SOYOMBO SUBJOINER
 11C30..11C36  ; Extend # Mn   [7] BHAIKSUKI VOWEL SIGN I..BHAIKSUKI VOWEL SIGN VOCALIC L
 11C38..11C3D  ; Extend # Mn   [6] BHAIKSUKI VOWEL SIGN E..BHAIKSUKI SIGN ANUSVARA
 11C3F         ; Extend # Mn       BHAIKSUKI SIGN VIRAMA
@@ -360,6 +374,11 @@ FF9E..FF9F    ; Extend # Lm   [2] HALFWIDTH KATAKANA VOICED SOUND MARK..HALFWIDT
 11CAA..11CB0  ; Extend # Mn   [7] MARCHEN SUBJOINED LETTER RA..MARCHEN VOWEL SIGN AA
 11CB2..11CB3  ; Extend # Mn   [2] MARCHEN VOWEL SIGN U..MARCHEN VOWEL SIGN E
 11CB5..11CB6  ; Extend # Mn   [2] MARCHEN SIGN ANUSVARA..MARCHEN SIGN CANDRABINDU
+11D31..11D36  ; Extend # Mn   [6] MASARAM GONDI VOWEL SIGN AA..MASARAM GONDI VOWEL SIGN VOCALIC R
+11D3A         ; Extend # Mn       MASARAM GONDI VOWEL SIGN E
+11D3C..11D3D  ; Extend # Mn   [2] MASARAM GONDI VOWEL SIGN AI..MASARAM GONDI VOWEL SIGN O
+11D3F..11D45  ; Extend # Mn   [7] MASARAM GONDI VOWEL SIGN AU..MASARAM GONDI VIRAMA
+11D47         ; Extend # Mn       MASARAM GONDI RA-KARA
 16AF0..16AF4  ; Extend # Mn   [5] BASSA VAH COMBINING HIGH TONE..BASSA VAH COMBINING HIGH-LOW TONE
 16B30..16B36  ; Extend # Mn   [7] PAHAWH HMONG MARK CIM TUB..PAHAWH HMONG MARK CIM TAUM
 16F8F..16F92  ; Extend # Mn   [4] MIAO TONE RIGHT..MIAO TONE BELOW
@@ -387,7 +406,7 @@ FF9E..FF9F    ; Extend # Lm   [2] HALFWIDTH KATAKANA VOICED SOUND MARK..HALFWIDT
 E0020..E007F  ; Extend # Cf  [96] TAG SPACE..CANCEL TAG
 E0100..E01EF  ; Extend # Mn [240] VARIATION SELECTOR-17..VARIATION SELECTOR-256
 
-# Total code points: 1828
+# Total code points: 1901
 
 # ================================================
 
@@ -472,6 +491,7 @@ E0100..E01EF  ; Extend # Mn [240] VARIATION SELECTOR-17..VARIATION SELECTOR-256
 1C34..1C35    ; SpacingMark # Mc   [2] LEPCHA CONSONANT SIGN NYIN-DO..LEPCHA CONSONANT SIGN KANG
 1CE1          ; SpacingMark # Mc       VEDIC TONE ATHARVAVEDIC INDEPENDENT SVARITA
 1CF2..1CF3    ; SpacingMark # Mc   [2] VEDIC SIGN ARDHAVISARGA..VEDIC SIGN ROTATED ARDHAVISARGA
+1CF7          ; SpacingMark # Mc       VEDIC SIGN ATIKRAMA
 A823..A824    ; SpacingMark # Mc   [2] SYLOTI NAGRI VOWEL SIGN A..SYLOTI NAGRI VOWEL SIGN I
 A827          ; SpacingMark # Mc       SYLOTI NAGRI VOWEL SIGN OO
 A880..A881    ; SpacingMark # Mc   [2] SAURASHTRA SIGN ANUSVARA..SAURASHTRA SIGN VISARGA
@@ -529,6 +549,10 @@ ABEC          ; SpacingMark # Mc       MEETEI MAYEK LUM IYEK
 116B6         ; SpacingMark # Mc       TAKRI SIGN VIRAMA
 11720..11721  ; SpacingMark # Mc   [2] AHOM VOWEL SIGN A..AHOM VOWEL SIGN AA
 11726         ; SpacingMark # Mc       AHOM VOWEL SIGN E
+11A07..11A08  ; SpacingMark # Mc   [2] ZANABAZAR SQUARE VOWEL SIGN AI..ZANABAZAR SQUARE VOWEL SIGN AU
+11A39         ; SpacingMark # Mc       ZANABAZAR SQUARE SIGN VISARGA
+11A57..11A58  ; SpacingMark # Mc   [2] SOYOMBO VOWEL SIGN AI..SOYOMBO VOWEL SIGN AU
+11A97         ; SpacingMark # Mc       SOYOMBO SIGN VISARGA
 11C2F         ; SpacingMark # Mc       BHAIKSUKI VOWEL SIGN AA
 11C3E         ; SpacingMark # Mc       BHAIKSUKI SIGN VISARGA
 11CA9         ; SpacingMark # Mc       MARCHEN SUBJOINED LETTER YA
@@ -538,7 +562,7 @@ ABEC          ; SpacingMark # Mc       MEETEI MAYEK LUM IYEK
 1D166         ; SpacingMark # Mc       MUSICAL SYMBOL COMBINING SPRECHGESANG STEM
 1D16D         ; SpacingMark # Mc       MUSICAL SYMBOL COMBINING AUGMENTATION DOT
 
-# Total code points: 341
+# Total code points: 348
 
 # ================================================
 
@@ -1375,8 +1399,9 @@ D789..D7A3    ; LVT # Lo  [27] HANGUL SYLLABLE HIG..HANGUL SYLLABLE HIH
 26F9          ; E_Base # So       PERSON WITH BALL
 270A..270D    ; E_Base # So   [4] RAISED FIST..WRITING HAND
 1F385         ; E_Base # So       FATHER CHRISTMAS
-1F3C3..1F3C4  ; E_Base # So   [2] RUNNER..SURFER
-1F3CA..1F3CB  ; E_Base # So   [2] SWIMMER..WEIGHT LIFTER
+1F3C2..1F3C4  ; E_Base # So   [3] SNOWBOARDER..SURFER
+1F3C7         ; E_Base # So       HORSE RACING
+1F3CA..1F3CC  ; E_Base # So   [3] SWIMMER..GOLFER
 1F442..1F443  ; E_Base # So   [2] EAR..NOSE
 1F446..1F450  ; E_Base # So  [11] WHITE UP POINTING BACKHAND INDEX..OPEN HANDS SIGN
 1F46E         ; E_Base # So       POLICE OFFICER
@@ -1385,7 +1410,7 @@ D789..D7A3    ; LVT # Lo  [27] HANGUL SYLLABLE HIG..HANGUL SYLLABLE HIH
 1F481..1F483  ; E_Base # So   [3] INFORMATION DESK PERSON..DANCER
 1F485..1F487  ; E_Base # So   [3] NAIL POLISH..HAIRCUT
 1F4AA         ; E_Base # So       FLEXED BICEPS
-1F575         ; E_Base # So       SLEUTH OR SPY
+1F574..1F575  ; E_Base # So   [2] MAN IN BUSINESS SUIT LEVITATING..SLEUTH OR SPY
 1F57A         ; E_Base # So       MAN DANCING
 1F590         ; E_Base # So       RAISED HAND WITH FINGERS SPLAYED
 1F595..1F596  ; E_Base # So   [2] REVERSED HAND WITH MIDDLE FINGER EXTENDED..RAISED HAND WITH PART BETWEEN MIDDLE AND RING FINGERS
@@ -1394,13 +1419,15 @@ D789..D7A3    ; LVT # Lo  [27] HANGUL SYLLABLE HIG..HANGUL SYLLABLE HIH
 1F6A3         ; E_Base # So       ROWBOAT
 1F6B4..1F6B6  ; E_Base # So   [3] BICYCLIST..PEDESTRIAN
 1F6C0         ; E_Base # So       BATH
-1F918..1F91E  ; E_Base # So   [7] SIGN OF THE HORNS..HAND WITH INDEX AND MIDDLE FINGERS CROSSED
+1F6CC         ; E_Base # So       SLEEPING ACCOMMODATION
+1F918..1F91C  ; E_Base # So   [5] SIGN OF THE HORNS..RIGHT-FACING FIST
+1F91E..1F91F  ; E_Base # So   [2] HAND WITH INDEX AND MIDDLE FINGERS CROSSED..I LOVE YOU HAND SIGN
 1F926         ; E_Base # So       FACE PALM
-1F930         ; E_Base # So       PREGNANT WOMAN
-1F933..1F939  ; E_Base # So   [7] SELFIE..JUGGLING
-1F93C..1F93E  ; E_Base # So   [3] WRESTLERS..HANDBALL
+1F930..1F939  ; E_Base # So  [10] PREGNANT WOMAN..JUGGLING
+1F93D..1F93E  ; E_Base # So   [2] WATER POLO..HANDBALL
+1F9D1..1F9DD  ; E_Base # So  [13] ADULT..ELF
 
-# Total code points: 79
+# Total code points: 98
 
 # ================================================
 
@@ -1416,11 +1443,28 @@ D789..D7A3    ; LVT # Lo  [27] HANGUL SYLLABLE HIG..HANGUL SYLLABLE HIH
 
 # ================================================
 
+2640          ; Glue_After_Zwj # So       FEMALE SIGN
+2642          ; Glue_After_Zwj # So       MALE SIGN
+2695..2696    ; Glue_After_Zwj # So   [2] STAFF OF AESCULAPIUS..SCALES
+2708          ; Glue_After_Zwj # So       AIRPLANE
 2764          ; Glue_After_Zwj # So       HEAVY BLACK HEART
+1F308         ; Glue_After_Zwj # So       RAINBOW
+1F33E         ; Glue_After_Zwj # So       EAR OF RICE
+1F373         ; Glue_After_Zwj # So       COOKING
+1F393         ; Glue_After_Zwj # So       GRADUATION CAP
+1F3A4         ; Glue_After_Zwj # So       MICROPHONE
+1F3A8         ; Glue_After_Zwj # So       ARTIST PALETTE
+1F3EB         ; Glue_After_Zwj # So       SCHOOL
+1F3ED         ; Glue_After_Zwj # So       FACTORY
 1F48B         ; Glue_After_Zwj # So       KISS MARK
+1F4BB..1F4BC  ; Glue_After_Zwj # So   [2] PERSONAL COMPUTER..BRIEFCASE
+1F527         ; Glue_After_Zwj # So       WRENCH
+1F52C         ; Glue_After_Zwj # So       MICROSCOPE
 1F5E8         ; Glue_After_Zwj # So       LEFT SPEECH BUBBLE
+1F680         ; Glue_After_Zwj # So       ROCKET
+1F692         ; Glue_After_Zwj # So       FIRE ENGINE
 
-# Total code points: 3
+# Total code points: 22
 
 # ================================================
 
diff --git a/lib/stdlib/uc_spec/PropList.txt b/lib/stdlib/uc_spec/PropList.txt
index a8c0da7135..9a2d0e4b1c 100644
--- a/lib/stdlib/uc_spec/PropList.txt
+++ b/lib/stdlib/uc_spec/PropList.txt
@@ -1,6 +1,6 @@
-# PropList-9.0.0.txt
-# Date: 2016-06-01, 10:34:30 GMT
-# © 2016 Unicode®, Inc.
+# PropList-10.0.0.txt
+# Date: 2017-03-10, 08:25:30 GMT
+# © 2017 Unicode®, Inc.
 # Unicode and the Unicode Logo are registered trademarks of Unicode, Inc. in the U.S. and other countries.
 # For terms of use, see http://www.unicode.org/terms_of_use.html
 #
@@ -199,6 +199,9 @@ FF64          ; Terminal_Punctuation # Po       HALFWIDTH IDEOGRAPHIC COMMA
 115C9..115D7  ; Terminal_Punctuation # Po  [15] SIDDHAM END OF TEXT MARK..SIDDHAM SECTION MARK WITH CIRCLES AND FOUR ENCLOSURES
 11641..11642  ; Terminal_Punctuation # Po   [2] MODI DANDA..MODI DOUBLE DANDA
 1173C..1173E  ; Terminal_Punctuation # Po   [3] AHOM SIGN SMALL SECTION..AHOM SIGN RULAI
+11A42..11A43  ; Terminal_Punctuation # Po   [2] ZANABAZAR SQUARE MARK SHAD..ZANABAZAR SQUARE MARK DOUBLE SHAD
+11A9B..11A9C  ; Terminal_Punctuation # Po   [2] SOYOMBO MARK SHAD..SOYOMBO MARK DOUBLE SHAD
+11AA1..11AA2  ; Terminal_Punctuation # Po   [2] SOYOMBO TERMINAL MARK-1..SOYOMBO TERMINAL MARK-2
 11C41..11C43  ; Terminal_Punctuation # Po   [3] BHAIKSUKI DANDA..BHAIKSUKI WORD SEPARATOR
 11C71         ; Terminal_Punctuation # Po       MARCHEN MARK SHAD
 12470..12474  ; Terminal_Punctuation # Po   [5] CUNEIFORM PUNCTUATION SIGN OLD ASSYRIAN WORD DIVIDER..CUNEIFORM PUNCTUATION SIGN DIAGONAL QUADCOLON
@@ -209,7 +212,7 @@ FF64          ; Terminal_Punctuation # Po       HALFWIDTH IDEOGRAPHIC COMMA
 1BC9F         ; Terminal_Punctuation # Po       DUPLOYAN PUNCTUATION CHINOOK FULL STOP
 1DA87..1DA8A  ; Terminal_Punctuation # Po   [4] SIGNWRITING COMMA..SIGNWRITING COLON
 
-# Total code points: 246
+# Total code points: 252
 
 # ================================================
 
@@ -471,6 +474,7 @@ FF41..FF46    ; Hex_Digit # L&   [6] FULLWIDTH LATIN SMALL LETTER A..FULLWIDTH L
 0AC9          ; Other_Alphabetic # Mc       GUJARATI VOWEL SIGN CANDRA O
 0ACB..0ACC    ; Other_Alphabetic # Mc   [2] GUJARATI VOWEL SIGN O..GUJARATI VOWEL SIGN AU
 0AE2..0AE3    ; Other_Alphabetic # Mn   [2] GUJARATI VOWEL SIGN VOCALIC L..GUJARATI VOWEL SIGN VOCALIC LL
+0AFA..0AFC    ; Other_Alphabetic # Mn   [3] GUJARATI SIGN SUKUN..GUJARATI SIGN MADDAH
 0B01          ; Other_Alphabetic # Mn       ORIYA SIGN CANDRABINDU
 0B02..0B03    ; Other_Alphabetic # Mc   [2] ORIYA SIGN ANUSVARA..ORIYA SIGN VISARGA
 0B3E          ; Other_Alphabetic # Mc       ORIYA VOWEL SIGN AA
@@ -508,7 +512,7 @@ FF41..FF46    ; Hex_Digit # L&   [6] FULLWIDTH LATIN SMALL LETTER A..FULLWIDTH L
 0CCC          ; Other_Alphabetic # Mn       KANNADA VOWEL SIGN AU
 0CD5..0CD6    ; Other_Alphabetic # Mc   [2] KANNADA LENGTH MARK..KANNADA AI LENGTH MARK
 0CE2..0CE3    ; Other_Alphabetic # Mn   [2] KANNADA VOWEL SIGN VOCALIC L..KANNADA VOWEL SIGN VOCALIC LL
-0D01          ; Other_Alphabetic # Mn       MALAYALAM SIGN CANDRABINDU
+0D00..0D01    ; Other_Alphabetic # Mn   [2] MALAYALAM SIGN COMBINING ANUSVARA ABOVE..MALAYALAM SIGN CANDRABINDU
 0D02..0D03    ; Other_Alphabetic # Mc   [2] MALAYALAM SIGN ANUSVARA..MALAYALAM SIGN VISARGA
 0D3E..0D40    ; Other_Alphabetic # Mc   [3] MALAYALAM VOWEL SIGN AA..MALAYALAM VOWEL SIGN II
 0D41..0D44    ; Other_Alphabetic # Mn   [4] MALAYALAM VOWEL SIGN U..MALAYALAM VOWEL SIGN VOCALIC RR
@@ -726,6 +730,17 @@ FB1E          ; Other_Alphabetic # Mn       HEBREW POINT JUDEO-SPANISH VARIKA
 11722..11725  ; Other_Alphabetic # Mn   [4] AHOM VOWEL SIGN I..AHOM VOWEL SIGN UU
 11726         ; Other_Alphabetic # Mc       AHOM VOWEL SIGN E
 11727..1172A  ; Other_Alphabetic # Mn   [4] AHOM VOWEL SIGN AW..AHOM VOWEL SIGN AM
+11A01..11A06  ; Other_Alphabetic # Mn   [6] ZANABAZAR SQUARE VOWEL SIGN I..ZANABAZAR SQUARE VOWEL SIGN O
+11A07..11A08  ; Other_Alphabetic # Mc   [2] ZANABAZAR SQUARE VOWEL SIGN AI..ZANABAZAR SQUARE VOWEL SIGN AU
+11A09..11A0A  ; Other_Alphabetic # Mn   [2] ZANABAZAR SQUARE VOWEL SIGN REVERSED I..ZANABAZAR SQUARE VOWEL LENGTH MARK
+11A35..11A38  ; Other_Alphabetic # Mn   [4] ZANABAZAR SQUARE SIGN CANDRABINDU..ZANABAZAR SQUARE SIGN ANUSVARA
+11A39         ; Other_Alphabetic # Mc       ZANABAZAR SQUARE SIGN VISARGA
+11A3B..11A3E  ; Other_Alphabetic # Mn   [4] ZANABAZAR SQUARE CLUSTER-FINAL LETTER YA..ZANABAZAR SQUARE CLUSTER-FINAL LETTER VA
+11A51..11A56  ; Other_Alphabetic # Mn   [6] SOYOMBO VOWEL SIGN I..SOYOMBO VOWEL SIGN OE
+11A57..11A58  ; Other_Alphabetic # Mc   [2] SOYOMBO VOWEL SIGN AI..SOYOMBO VOWEL SIGN AU
+11A59..11A5B  ; Other_Alphabetic # Mn   [3] SOYOMBO VOWEL SIGN VOCALIC R..SOYOMBO VOWEL LENGTH MARK
+11A8A..11A96  ; Other_Alphabetic # Mn  [13] SOYOMBO FINAL CONSONANT SIGN G..SOYOMBO SIGN ANUSVARA
+11A97         ; Other_Alphabetic # Mc       SOYOMBO SIGN VISARGA
 11C2F         ; Other_Alphabetic # Mc       BHAIKSUKI VOWEL SIGN AA
 11C30..11C36  ; Other_Alphabetic # Mn   [7] BHAIKSUKI VOWEL SIGN I..BHAIKSUKI VOWEL SIGN VOCALIC L
 11C38..11C3D  ; Other_Alphabetic # Mn   [6] BHAIKSUKI VOWEL SIGN E..BHAIKSUKI SIGN ANUSVARA
@@ -737,6 +752,12 @@ FB1E          ; Other_Alphabetic # Mn       HEBREW POINT JUDEO-SPANISH VARIKA
 11CB2..11CB3  ; Other_Alphabetic # Mn   [2] MARCHEN VOWEL SIGN U..MARCHEN VOWEL SIGN E
 11CB4         ; Other_Alphabetic # Mc       MARCHEN VOWEL SIGN O
 11CB5..11CB6  ; Other_Alphabetic # Mn   [2] MARCHEN SIGN ANUSVARA..MARCHEN SIGN CANDRABINDU
+11D31..11D36  ; Other_Alphabetic # Mn   [6] MASARAM GONDI VOWEL SIGN AA..MASARAM GONDI VOWEL SIGN VOCALIC R
+11D3A         ; Other_Alphabetic # Mn       MASARAM GONDI VOWEL SIGN E
+11D3C..11D3D  ; Other_Alphabetic # Mn   [2] MASARAM GONDI VOWEL SIGN AI..MASARAM GONDI VOWEL SIGN O
+11D3F..11D41  ; Other_Alphabetic # Mn   [3] MASARAM GONDI VOWEL SIGN AU..MASARAM GONDI SIGN VISARGA
+11D43         ; Other_Alphabetic # Mn       MASARAM GONDI SIGN CANDRA
+11D47         ; Other_Alphabetic # Mn       MASARAM GONDI RA-KARA
 16B30..16B36  ; Other_Alphabetic # Mn   [7] PAHAWH HMONG MARK CIM TUB..PAHAWH HMONG MARK CIM TAUM
 16F51..16F7E  ; Other_Alphabetic # Mc  [46] MIAO SIGN ASPIRATION..MIAO VOWEL SIGN NG
 1BC9E         ; Other_Alphabetic # Mn       DUPLOYAN DOUBLE MARK
@@ -750,7 +771,7 @@ FB1E          ; Other_Alphabetic # Mn       HEBREW POINT JUDEO-SPANISH VARIKA
 1F150..1F169  ; Other_Alphabetic # So  [26] NEGATIVE CIRCLED LATIN CAPITAL LETTER A..NEGATIVE CIRCLED LATIN CAPITAL LETTER Z
 1F170..1F189  ; Other_Alphabetic # So  [26] NEGATIVE SQUARED LATIN CAPITAL LETTER A..NEGATIVE SQUARED LATIN CAPITAL LETTER Z
 
-# Total code points: 1238
+# Total code points: 1300
 
 # ================================================
 
@@ -759,18 +780,20 @@ FB1E          ; Other_Alphabetic # Mn       HEBREW POINT JUDEO-SPANISH VARIKA
 3021..3029    ; Ideographic # Nl   [9] HANGZHOU NUMERAL ONE..HANGZHOU NUMERAL NINE
 3038..303A    ; Ideographic # Nl   [3] HANGZHOU NUMERAL TEN..HANGZHOU NUMERAL THIRTY
 3400..4DB5    ; Ideographic # Lo [6582] CJK UNIFIED IDEOGRAPH-3400..CJK UNIFIED IDEOGRAPH-4DB5
-4E00..9FD5    ; Ideographic # Lo [20950] CJK UNIFIED IDEOGRAPH-4E00..CJK UNIFIED IDEOGRAPH-9FD5
+4E00..9FEA    ; Ideographic # Lo [20971] CJK UNIFIED IDEOGRAPH-4E00..CJK UNIFIED IDEOGRAPH-9FEA
 F900..FA6D    ; Ideographic # Lo [366] CJK COMPATIBILITY IDEOGRAPH-F900..CJK COMPATIBILITY IDEOGRAPH-FA6D
 FA70..FAD9    ; Ideographic # Lo [106] CJK COMPATIBILITY IDEOGRAPH-FA70..CJK COMPATIBILITY IDEOGRAPH-FAD9
 17000..187EC  ; Ideographic # Lo [6125] TANGUT IDEOGRAPH-17000..TANGUT IDEOGRAPH-187EC
 18800..18AF2  ; Ideographic # Lo [755] TANGUT COMPONENT-001..TANGUT COMPONENT-755
+1B170..1B2FB  ; Ideographic # Lo [396] NUSHU CHARACTER-1B170..NUSHU CHARACTER-1B2FB
 20000..2A6D6  ; Ideographic # Lo [42711] CJK UNIFIED IDEOGRAPH-20000..CJK UNIFIED IDEOGRAPH-2A6D6
 2A700..2B734  ; Ideographic # Lo [4149] CJK UNIFIED IDEOGRAPH-2A700..CJK UNIFIED IDEOGRAPH-2B734
 2B740..2B81D  ; Ideographic # Lo [222] CJK UNIFIED IDEOGRAPH-2B740..CJK UNIFIED IDEOGRAPH-2B81D
 2B820..2CEA1  ; Ideographic # Lo [5762] CJK UNIFIED IDEOGRAPH-2B820..CJK UNIFIED IDEOGRAPH-2CEA1
+2CEB0..2EBE0  ; Ideographic # Lo [7473] CJK UNIFIED IDEOGRAPH-2CEB0..CJK UNIFIED IDEOGRAPH-2EBE0
 2F800..2FA1D  ; Ideographic # Lo [542] CJK COMPATIBILITY IDEOGRAPH-2F800..CJK COMPATIBILITY IDEOGRAPH-2FA1D
 
-# Total code points: 88284
+# Total code points: 96174
 
 # ================================================
 
@@ -826,12 +849,14 @@ FA70..FAD9    ; Ideographic # Lo [106] CJK COMPATIBILITY IDEOGRAPH-FA70..CJK COM
 0A4D          ; Diacritic # Mn       GURMUKHI SIGN VIRAMA
 0ABC          ; Diacritic # Mn       GUJARATI SIGN NUKTA
 0ACD          ; Diacritic # Mn       GUJARATI SIGN VIRAMA
+0AFD..0AFF    ; Diacritic # Mn   [3] GUJARATI SIGN THREE-DOT NUKTA ABOVE..GUJARATI SIGN TWO-CIRCLE NUKTA ABOVE
 0B3C          ; Diacritic # Mn       ORIYA SIGN NUKTA
 0B4D          ; Diacritic # Mn       ORIYA SIGN VIRAMA
 0BCD          ; Diacritic # Mn       TAMIL SIGN VIRAMA
 0C4D          ; Diacritic # Mn       TELUGU SIGN VIRAMA
 0CBC          ; Diacritic # Mn       KANNADA SIGN NUKTA
 0CCD          ; Diacritic # Mn       KANNADA SIGN VIRAMA
+0D3B..0D3C    ; Diacritic # Mn   [2] MALAYALAM SIGN VERTICAL BAR VIRAMA..MALAYALAM SIGN CIRCULAR VIRAMA
 0D4D          ; Diacritic # Mn       MALAYALAM SIGN VIRAMA
 0DCA          ; Diacritic # Mn       SINHALA SIGN AL-LAKUNA
 0E47..0E4C    ; Diacritic # Mn   [6] THAI CHARACTER MAITAIKHU..THAI CHARACTER THANTHAKHAT
@@ -871,10 +896,11 @@ FA70..FAD9    ; Ideographic # Lo [106] CJK COMPATIBILITY IDEOGRAPH-FA70..CJK COM
 1CE2..1CE8    ; Diacritic # Mn   [7] VEDIC SIGN VISARGA SVARITA..VEDIC SIGN VISARGA ANUDATTA WITH TAIL
 1CED          ; Diacritic # Mn       VEDIC SIGN TIRYAK
 1CF4          ; Diacritic # Mn       VEDIC TONE CANDRA ABOVE
+1CF7          ; Diacritic # Mc       VEDIC SIGN ATIKRAMA
 1CF8..1CF9    ; Diacritic # Mn   [2] VEDIC TONE RING ABOVE..VEDIC TONE DOUBLE RING ABOVE
 1D2C..1D6A    ; Diacritic # Lm  [63] MODIFIER LETTER CAPITAL A..GREEK SUBSCRIPT SMALL LETTER CHI
 1DC4..1DCF    ; Diacritic # Mn  [12] COMBINING MACRON-ACUTE..COMBINING ZIGZAG BELOW
-1DF5          ; Diacritic # Mn       COMBINING UP TACK ABOVE
+1DF5..1DF9    ; Diacritic # Mn   [5] COMBINING UP TACK ABOVE..COMBINING WIDE INVERTED BRIDGE BELOW
 1DFD..1DFF    ; Diacritic # Mn   [3] COMBINING ALMOST EQUAL TO BELOW..COMBINING RIGHT ARROWHEAD AND DOWN ARROWHEAD BELOW
 1FBD          ; Diacritic # Sk       GREEK KORONIS
 1FBF..1FC1    ; Diacritic # Sk   [3] GREEK PSILI..GREEK DIALYTIKA AND PERISPOMENI
@@ -947,7 +973,12 @@ FFE3          ; Diacritic # Sk       FULLWIDTH MACRON
 116B6         ; Diacritic # Mc       TAKRI SIGN VIRAMA
 116B7         ; Diacritic # Mn       TAKRI SIGN NUKTA
 1172B         ; Diacritic # Mn       AHOM SIGN KILLER
+11A34         ; Diacritic # Mn       ZANABAZAR SQUARE SIGN VIRAMA
+11A47         ; Diacritic # Mn       ZANABAZAR SQUARE SUBJOINER
+11A99         ; Diacritic # Mn       SOYOMBO SUBJOINER
 11C3F         ; Diacritic # Mn       BHAIKSUKI SIGN VIRAMA
+11D42         ; Diacritic # Mn       MASARAM GONDI SIGN NUKTA
+11D44..11D45  ; Diacritic # Mn   [2] MASARAM GONDI SIGN HALANTA..MASARAM GONDI VIRAMA
 16AF0..16AF4  ; Diacritic # Mn   [5] BASSA VAH COMBINING HIGH TONE..BASSA VAH COMBINING HIGH-LOW TONE
 16F8F..16F92  ; Diacritic # Mn   [4] MIAO TONE RIGHT..MIAO TONE BELOW
 16F93..16F9F  ; Diacritic # Lm  [13] MIAO LETTER TONE-2..MIAO LETTER REFORMED TONE-8
@@ -960,7 +991,7 @@ FFE3          ; Diacritic # Sk       FULLWIDTH MACRON
 1E944..1E946  ; Diacritic # Mn   [3] ADLAM ALIF LENGTHENER..ADLAM GEMINATION MARK
 1E948..1E94A  ; Diacritic # Mn   [3] ADLAM CONSONANT MODIFIER..ADLAM NUKTA
 
-# Total code points: 782
+# Total code points: 798
 
 # ================================================
 
@@ -989,11 +1020,12 @@ AAF3..AAF4    ; Extender # Lm   [2] MEETEI MAYEK SYLLABLE REPETITION MARK..MEETE
 FF70          ; Extender # Lm       HALFWIDTH KATAKANA-HIRAGANA PROLONGED SOUND MARK
 1135D         ; Extender # Lo       GRANTHA SIGN PLUTA
 115C6..115C8  ; Extender # Po   [3] SIDDHAM REPETITION MARK-1..SIDDHAM REPETITION MARK-3
+11A98         ; Extender # Mn       SOYOMBO GEMINATION MARK
 16B42..16B43  ; Extender # Lm   [2] PAHAWH HMONG SIGN VOS NRUA..PAHAWH HMONG SIGN IB YAM
-16FE0         ; Extender # Lm       TANGUT ITERATION MARK
+16FE0..16FE1  ; Extender # Lm   [2] TANGUT ITERATION MARK..NUSHU ITERATION MARK
 1E944..1E946  ; Extender # Mn   [3] ADLAM ALIF LENGTHENER..ADLAM GEMINATION MARK
 
-# Total code points: 42
+# Total code points: 44
 
 # ================================================
 
@@ -1105,7 +1137,7 @@ E0020..E007F  ; Other_Grapheme_Extend # Cf  [96] TAG SPACE..CANCEL TAG
 # ================================================
 
 3400..4DB5    ; Unified_Ideograph # Lo [6582] CJK UNIFIED IDEOGRAPH-3400..CJK UNIFIED IDEOGRAPH-4DB5
-4E00..9FD5    ; Unified_Ideograph # Lo [20950] CJK UNIFIED IDEOGRAPH-4E00..CJK UNIFIED IDEOGRAPH-9FD5
+4E00..9FEA    ; Unified_Ideograph # Lo [20971] CJK UNIFIED IDEOGRAPH-4E00..CJK UNIFIED IDEOGRAPH-9FEA
 FA0E..FA0F    ; Unified_Ideograph # Lo   [2] CJK COMPATIBILITY IDEOGRAPH-FA0E..CJK COMPATIBILITY IDEOGRAPH-FA0F
 FA11          ; Unified_Ideograph # Lo       CJK COMPATIBILITY IDEOGRAPH-FA11
 FA13..FA14    ; Unified_Ideograph # Lo   [2] CJK COMPATIBILITY IDEOGRAPH-FA13..CJK COMPATIBILITY IDEOGRAPH-FA14
@@ -1117,8 +1149,9 @@ FA27..FA29    ; Unified_Ideograph # Lo   [3] CJK COMPATIBILITY IDEOGRAPH-FA27..C
 2A700..2B734  ; Unified_Ideograph # Lo [4149] CJK UNIFIED IDEOGRAPH-2A700..CJK UNIFIED IDEOGRAPH-2B734
 2B740..2B81D  ; Unified_Ideograph # Lo [222] CJK UNIFIED IDEOGRAPH-2B740..CJK UNIFIED IDEOGRAPH-2B81D
 2B820..2CEA1  ; Unified_Ideograph # Lo [5762] CJK UNIFIED IDEOGRAPH-2B820..CJK UNIFIED IDEOGRAPH-2CEA1
+2CEB0..2EBE0  ; Unified_Ideograph # Lo [7473] CJK UNIFIED IDEOGRAPH-2CEB0..CJK UNIFIED IDEOGRAPH-2EBE0
 
-# Total code points: 80388
+# Total code points: 87882
 
 # ================================================
 
@@ -1277,6 +1310,8 @@ FF61          ; Sentence_Terminal # Po       HALFWIDTH IDEOGRAPHIC FULL STOP
 115C9..115D7  ; Sentence_Terminal # Po  [15] SIDDHAM END OF TEXT MARK..SIDDHAM SECTION MARK WITH CIRCLES AND FOUR ENCLOSURES
 11641..11642  ; Sentence_Terminal # Po   [2] MODI DANDA..MODI DOUBLE DANDA
 1173C..1173E  ; Sentence_Terminal # Po   [3] AHOM SIGN SMALL SECTION..AHOM SIGN RULAI
+11A42..11A43  ; Sentence_Terminal # Po   [2] ZANABAZAR SQUARE MARK SHAD..ZANABAZAR SQUARE MARK DOUBLE SHAD
+11A9B..11A9C  ; Sentence_Terminal # Po   [2] SOYOMBO MARK SHAD..SOYOMBO MARK DOUBLE SHAD
 11C41..11C42  ; Sentence_Terminal # Po   [2] BHAIKSUKI DANDA..BHAIKSUKI DOUBLE DANDA
 16A6E..16A6F  ; Sentence_Terminal # Po   [2] MRO DANDA..MRO DOUBLE DANDA
 16AF5         ; Sentence_Terminal # Po       BASSA VAH FULL STOP
@@ -1285,7 +1320,7 @@ FF61          ; Sentence_Terminal # Po       HALFWIDTH IDEOGRAPHIC FULL STOP
 1BC9F         ; Sentence_Terminal # Po       DUPLOYAN PUNCTUATION CHINOOK FULL STOP
 1DA88         ; Sentence_Terminal # Po       SIGNWRITING FULL STOP
 
-# Total code points: 124
+# Total code points: 128
 
 # ================================================
 
@@ -1402,9 +1437,7 @@ E0100..E01EF  ; Variation_Selector # Mn [240] VARIATION SELECTOR-17..VARIATION S
 239B..23B3    ; Pattern_Syntax # Sm  [25] LEFT PARENTHESIS UPPER HOOK..SUMMATION BOTTOM
 23B4..23DB    ; Pattern_Syntax # So  [40] TOP SQUARE BRACKET..FUSE
 23DC..23E1    ; Pattern_Syntax # Sm   [6] TOP PARENTHESIS..BOTTOM TORTOISE SHELL BRACKET
-23E2..23FE    ; Pattern_Syntax # So  [29] WHITE TRAPEZIUM..POWER SLEEP SYMBOL
-23FF          ; Pattern_Syntax # Cn       <reserved-23FF>
-2400..2426    ; Pattern_Syntax # So  [39] SYMBOL FOR NULL..SYMBOL FOR SUBSTITUTE FORM TWO
+23E2..2426    ; Pattern_Syntax # So  [69] WHITE TRAPEZIUM..SYMBOL FOR SUBSTITUTE FORM TWO
 2427..243F    ; Pattern_Syntax # Cn  [25] <reserved-2427>..<reserved-243F>
 2440..244A    ; Pattern_Syntax # So  [11] OCR HOOK..OCR DOUBLE BACKSLASH
 244B..245F    ; Pattern_Syntax # Cn  [21] <reserved-244B>..<reserved-245F>
@@ -1492,8 +1525,8 @@ E0100..E01EF  ; Variation_Selector # Mn [240] VARIATION SELECTOR-17..VARIATION S
 2BBA..2BBC    ; Pattern_Syntax # Cn   [3] <reserved-2BBA>..<reserved-2BBC>
 2BBD..2BC8    ; Pattern_Syntax # So  [12] BALLOT BOX WITH LIGHT X..BLACK MEDIUM RIGHT-POINTING TRIANGLE CENTRED
 2BC9          ; Pattern_Syntax # Cn       <reserved-2BC9>
-2BCA..2BD1    ; Pattern_Syntax # So   [8] TOP HALF BLACK CIRCLE..UNCERTAINTY SIGN
-2BD2..2BEB    ; Pattern_Syntax # Cn  [26] <reserved-2BD2>..<reserved-2BEB>
+2BCA..2BD2    ; Pattern_Syntax # So   [9] TOP HALF BLACK CIRCLE..GROUP MARK
+2BD3..2BEB    ; Pattern_Syntax # Cn  [25] <reserved-2BD3>..<reserved-2BEB>
 2BEC..2BEF    ; Pattern_Syntax # So   [4] LEFTWARDS TWO-HEADED ARROW WITH TRIANGLE ARROWHEADS..DOWNWARDS TWO-HEADED ARROW WITH TRIANGLE ARROWHEADS
 2BF0..2BFF    ; Pattern_Syntax # Cn  [16] <reserved-2BF0>..<reserved-2BFF>
 2E00..2E01    ; Pattern_Syntax # Po   [2] RIGHT ANGLE SUBSTITUTION MARKER..RIGHT ANGLE DOTTED SUBSTITUTION MARKER
@@ -1533,8 +1566,8 @@ E0100..E01EF  ; Variation_Selector # Mn [240] VARIATION SELECTOR-17..VARIATION S
 2E40          ; Pattern_Syntax # Pd       DOUBLE HYPHEN
 2E41          ; Pattern_Syntax # Po       REVERSED COMMA
 2E42          ; Pattern_Syntax # Ps       DOUBLE LOW-REVERSED-9 QUOTATION MARK
-2E43..2E44    ; Pattern_Syntax # Po   [2] DASH WITH LEFT UPTURN..DOUBLE SUSPENSION MARK
-2E45..2E7F    ; Pattern_Syntax # Cn  [59] <reserved-2E45>..<reserved-2E7F>
+2E43..2E49    ; Pattern_Syntax # Po   [7] DASH WITH LEFT UPTURN..DOUBLE STACKED COMMA
+2E4A..2E7F    ; Pattern_Syntax # Cn  [54] <reserved-2E4A>..<reserved-2E7F>
 3001..3003    ; Pattern_Syntax # Po   [3] IDEOGRAPHIC COMMA..DITTO MARK
 3008          ; Pattern_Syntax # Ps       LEFT ANGLE BRACKET
 3009          ; Pattern_Syntax # Pe       RIGHT ANGLE BRACKET
@@ -1576,4 +1609,10 @@ FE45..FE46    ; Pattern_Syntax # Po   [2] SESAME DOT..WHITE SESAME DOT
 
 # Total code points: 10
 
+# ================================================
+
+1F1E6..1F1FF  ; Regional_Indicator # So  [26] REGIONAL INDICATOR SYMBOL LETTER A..REGIONAL INDICATOR SYMBOL LETTER Z
+
+# Total code points: 26
+
 # EOF
diff --git a/lib/stdlib/uc_spec/SpecialCasing.txt b/lib/stdlib/uc_spec/SpecialCasing.txt
index b23fa7f768..b9ba0d81c1 100644
--- a/lib/stdlib/uc_spec/SpecialCasing.txt
+++ b/lib/stdlib/uc_spec/SpecialCasing.txt
@@ -1,6 +1,6 @@
-# SpecialCasing-9.0.0.txt
-# Date: 2016-03-02, 18:55:13 GMT
-# © 2016 Unicode®, Inc.
+# SpecialCasing-10.0.0.txt
+# Date: 2017-04-14, 05:40:43 GMT
+# © 2017 Unicode®, Inc.
 # Unicode and the Unicode Logo are registered trademarks of Unicode, Inc. in the U.S. and other countries.
 # For terms of use, see http://www.unicode.org/terms_of_use.html
 #
@@ -197,7 +197,7 @@ FB17; FB17; 0544 056D; 0544 053D; # ARMENIAN SMALL LIGATURE MEN XEH
 
 # ================================================================================
 # Conditional Mappings
-# The remainder of this file provides conditional casing data used to produce 
+# The remainder of this file provides conditional casing data used to produce
 # full case mappings.
 # ================================================================================
 # Language-Insensitive Mappings
diff --git a/lib/stdlib/uc_spec/UnicodeData.txt b/lib/stdlib/uc_spec/UnicodeData.txt
index a756976461..d89c64f526 100644
--- a/lib/stdlib/uc_spec/UnicodeData.txt
+++ b/lib/stdlib/uc_spec/UnicodeData.txt
@@ -2072,6 +2072,17 @@
 085A;MANDAIC VOCALIZATION MARK;Mn;220;NSM;;;;;N;;;;;
 085B;MANDAIC GEMINATION MARK;Mn;220;NSM;;;;;N;;;;;
 085E;MANDAIC PUNCTUATION;Po;0;R;;;;;N;;;;;
+0860;SYRIAC LETTER MALAYALAM NGA;Lo;0;AL;;;;;N;;;;;
+0861;SYRIAC LETTER MALAYALAM JA;Lo;0;AL;;;;;N;;;;;
+0862;SYRIAC LETTER MALAYALAM NYA;Lo;0;AL;;;;;N;;;;;
+0863;SYRIAC LETTER MALAYALAM TTA;Lo;0;AL;;;;;N;;;;;
+0864;SYRIAC LETTER MALAYALAM NNA;Lo;0;AL;;;;;N;;;;;
+0865;SYRIAC LETTER MALAYALAM NNNA;Lo;0;AL;;;;;N;;;;;
+0866;SYRIAC LETTER MALAYALAM BHA;Lo;0;AL;;;;;N;;;;;
+0867;SYRIAC LETTER MALAYALAM RA;Lo;0;AL;;;;;N;;;;;
+0868;SYRIAC LETTER MALAYALAM LLA;Lo;0;AL;;;;;N;;;;;
+0869;SYRIAC LETTER MALAYALAM LLLA;Lo;0;AL;;;;;N;;;;;
+086A;SYRIAC LETTER MALAYALAM SSA;Lo;0;AL;;;;;N;;;;;
 08A0;ARABIC LETTER BEH WITH SMALL V BELOW;Lo;0;AL;;;;;N;;;;;
 08A1;ARABIC LETTER BEH WITH HAMZA ABOVE;Lo;0;AL;;;;;N;;;;;
 08A2;ARABIC LETTER JEEM WITH TWO DOTS ABOVE;Lo;0;AL;;;;;N;;;;;
@@ -2366,6 +2377,8 @@
 09F9;BENGALI CURRENCY DENOMINATOR SIXTEEN;No;0;L;;;;16;N;;;;;
 09FA;BENGALI ISSHAR;So;0;L;;;;;N;;;;;
 09FB;BENGALI GANDA MARK;Sc;0;ET;;;;;N;;;;;
+09FC;BENGALI LETTER VEDIC ANUSVARA;Lo;0;L;;;;;N;;;;;
+09FD;BENGALI ABBREVIATION SIGN;Po;0;L;;;;;N;;;;;
 0A01;GURMUKHI SIGN ADAK BINDI;Mn;0;NSM;;;;;N;;;;;
 0A02;GURMUKHI SIGN BINDI;Mn;0;NSM;;;;;N;;;;;
 0A03;GURMUKHI SIGN VISARGA;Mc;0;L;;;;;N;;;;;
@@ -2530,6 +2543,12 @@
 0AF0;GUJARATI ABBREVIATION SIGN;Po;0;L;;;;;N;;;;;
 0AF1;GUJARATI RUPEE SIGN;Sc;0;ET;;;;;N;;;;;
 0AF9;GUJARATI LETTER ZHA;Lo;0;L;;;;;N;;;;;
+0AFA;GUJARATI SIGN SUKUN;Mn;0;NSM;;;;;N;;;;;
+0AFB;GUJARATI SIGN SHADDA;Mn;0;NSM;;;;;N;;;;;
+0AFC;GUJARATI SIGN MADDAH;Mn;0;NSM;;;;;N;;;;;
+0AFD;GUJARATI SIGN THREE-DOT NUKTA ABOVE;Mn;0;NSM;;;;;N;;;;;
+0AFE;GUJARATI SIGN CIRCLE NUKTA ABOVE;Mn;0;NSM;;;;;N;;;;;
+0AFF;GUJARATI SIGN TWO-CIRCLE NUKTA ABOVE;Mn;0;NSM;;;;;N;;;;;
 0B01;ORIYA SIGN CANDRABINDU;Mn;0;NSM;;;;;N;;;;;
 0B02;ORIYA SIGN ANUSVARA;Mc;0;L;;;;;N;;;;;
 0B03;ORIYA SIGN VISARGA;Mc;0;L;;;;;N;;;;;
@@ -2876,6 +2895,7 @@
 0CEF;KANNADA DIGIT NINE;Nd;0;L;;9;9;9;N;;;;;
 0CF1;KANNADA SIGN JIHVAMULIYA;Lo;0;L;;;;;N;;;;;
 0CF2;KANNADA SIGN UPADHMANIYA;Lo;0;L;;;;;N;;;;;
+0D00;MALAYALAM SIGN COMBINING ANUSVARA ABOVE;Mn;0;NSM;;;;;N;;;;;
 0D01;MALAYALAM SIGN CANDRABINDU;Mn;0;NSM;;;;;N;;;;;
 0D02;MALAYALAM SIGN ANUSVARA;Mc;0;L;;;;;N;;;;;
 0D03;MALAYALAM SIGN VISARGA;Mc;0;L;;;;;N;;;;;
@@ -2931,6 +2951,8 @@
 0D38;MALAYALAM LETTER SA;Lo;0;L;;;;;N;;;;;
 0D39;MALAYALAM LETTER HA;Lo;0;L;;;;;N;;;;;
 0D3A;MALAYALAM LETTER TTTA;Lo;0;L;;;;;N;;;;;
+0D3B;MALAYALAM SIGN VERTICAL BAR VIRAMA;Mn;9;NSM;;;;;N;;;;;
+0D3C;MALAYALAM SIGN CIRCULAR VIRAMA;Mn;9;NSM;;;;;N;;;;;
 0D3D;MALAYALAM SIGN AVAGRAHA;Lo;0;L;;;;;N;;;;;
 0D3E;MALAYALAM VOWEL SIGN AA;Mc;0;L;;;;;N;;;;;
 0D3F;MALAYALAM VOWEL SIGN I;Mc;0;L;;;;;N;;;;;
@@ -6413,6 +6435,7 @@
 1CF4;VEDIC TONE CANDRA ABOVE;Mn;230;NSM;;;;;N;;;;;
 1CF5;VEDIC SIGN JIHVAMULIYA;Lo;0;L;;;;;N;;;;;
 1CF6;VEDIC SIGN UPADHMANIYA;Lo;0;L;;;;;N;;;;;
+1CF7;VEDIC SIGN ATIKRAMA;Mc;0;L;;;;;N;;;;;
 1CF8;VEDIC TONE RING ABOVE;Mn;230;NSM;;;;;N;;;;;
 1CF9;VEDIC TONE DOUBLE RING ABOVE;Mn;230;NSM;;;;;N;;;;;
 1D00;LATIN LETTER SMALL CAPITAL A;Ll;0;L;;;;;N;;;;;
@@ -6661,6 +6684,10 @@
 1DF3;COMBINING LATIN SMALL LETTER O WITH DIAERESIS;Mn;230;NSM;;;;;N;;;;;
 1DF4;COMBINING LATIN SMALL LETTER U WITH DIAERESIS;Mn;230;NSM;;;;;N;;;;;
 1DF5;COMBINING UP TACK ABOVE;Mn;230;NSM;;;;;N;;;;;
+1DF6;COMBINING KAVYKA ABOVE RIGHT;Mn;232;NSM;;;;;N;;;;;
+1DF7;COMBINING KAVYKA ABOVE LEFT;Mn;228;NSM;;;;;N;;;;;
+1DF8;COMBINING DOT ABOVE LEFT;Mn;228;NSM;;;;;N;;;;;
+1DF9;COMBINING WIDE INVERTED BRIDGE BELOW;Mn;220;NSM;;;;;N;;;;;
 1DFB;COMBINING DELETION MARK;Mn;230;NSM;;;;;N;;;;;
 1DFC;COMBINING DOUBLE INVERTED BREVE BELOW;Mn;233;NSM;;;;;N;;;;;
 1DFD;COMBINING ALMOST EQUAL TO BELOW;Mn;220;NSM;;;;;N;;;;;
@@ -7339,6 +7366,7 @@
 20BC;MANAT SIGN;Sc;0;ET;;;;;N;;;;;
 20BD;RUBLE SIGN;Sc;0;ET;;;;;N;;;;;
 20BE;LARI SIGN;Sc;0;ET;;;;;N;;;;;
+20BF;BITCOIN SIGN;Sc;0;ET;;;;;N;;;;;
 20D0;COMBINING LEFT HARPOON ABOVE;Mn;230;NSM;;;;;N;NON-SPACING LEFT HARPOON ABOVE;;;;
 20D1;COMBINING RIGHT HARPOON ABOVE;Mn;230;NSM;;;;;N;NON-SPACING RIGHT HARPOON ABOVE;;;;
 20D2;COMBINING LONG VERTICAL LINE OVERLAY;Mn;1;NSM;;;;;N;NON-SPACING LONG VERTICAL BAR OVERLAY;;;;
@@ -8135,6 +8163,7 @@
 23FC;POWER ON-OFF SYMBOL;So;0;ON;;;;;N;;;;;
 23FD;POWER ON SYMBOL;So;0;ON;;;;;N;;;;;
 23FE;POWER SLEEP SYMBOL;So;0;ON;;;;;N;;;;;
+23FF;OBSERVER EYE SYMBOL;So;0;ON;;;;;N;;;;;
 2400;SYMBOL FOR NULL;So;0;ON;;;;;N;GRAPHIC FOR NULL;;;;
 2401;SYMBOL FOR START OF HEADING;So;0;ON;;;;;N;GRAPHIC FOR START OF HEADING;;;;
 2402;SYMBOL FOR START OF TEXT;So;0;ON;;;;;N;GRAPHIC FOR START OF TEXT;;;;
@@ -10083,6 +10112,7 @@
 2BCF;ROTATED WHITE FOUR POINTED CUSP;So;0;ON;;;;;N;;;;;
 2BD0;SQUARE POSITION INDICATOR;So;0;ON;;;;;N;;;;;
 2BD1;UNCERTAINTY SIGN;So;0;ON;;;;;N;;;;;
+2BD2;GROUP MARK;So;0;ON;;;;;N;;;;;
 2BEC;LEFTWARDS TWO-HEADED ARROW WITH TRIANGLE ARROWHEADS;So;0;ON;;;;;N;;;;;
 2BED;UPWARDS TWO-HEADED ARROW WITH TRIANGLE ARROWHEADS;So;0;ON;;;;;N;;;;;
 2BEE;RIGHTWARDS TWO-HEADED ARROW WITH TRIANGLE ARROWHEADS;So;0;ON;;;;;N;;;;;
@@ -10615,6 +10645,11 @@
 2E42;DOUBLE LOW-REVERSED-9 QUOTATION MARK;Ps;0;ON;;;;;N;;;;;
 2E43;DASH WITH LEFT UPTURN;Po;0;ON;;;;;N;;;;;
 2E44;DOUBLE SUSPENSION MARK;Po;0;ON;;;;;N;;;;;
+2E45;INVERTED LOW KAVYKA;Po;0;ON;;;;;N;;;;;
+2E46;INVERTED LOW KAVYKA WITH KAVYKA ABOVE;Po;0;ON;;;;;N;;;;;
+2E47;LOW KAVYKA;Po;0;ON;;;;;N;;;;;
+2E48;LOW KAVYKA WITH DOT;Po;0;ON;;;;;N;;;;;
+2E49;DOUBLE STACKED COMMA;Po;0;ON;;;;;N;;;;;
 2E80;CJK RADICAL REPEAT;So;0;ON;;;;;N;;;;;
 2E81;CJK RADICAL CLIFF;So;0;ON;;;;;N;;;;;
 2E82;CJK RADICAL SECOND ONE;So;0;ON;;;;;N;;;;;
@@ -11250,6 +11285,7 @@
 312B;BOPOMOFO LETTER NG;Lo;0;L;;;;;N;;;;;
 312C;BOPOMOFO LETTER GN;Lo;0;L;;;;;N;;;;;
 312D;BOPOMOFO LETTER IH;Lo;0;L;;;;;N;;;;;
+312E;BOPOMOFO LETTER O WITH DOT ABOVE;Lo;0;L;;;;;N;;;;;
 3131;HANGUL LETTER KIYEOK;Lo;0;L;<compat> 1100;;;;N;HANGUL LETTER GIYEOG;;;;
 3132;HANGUL LETTER SSANGKIYEOK;Lo;0;L;<compat> 1101;;;;N;HANGUL LETTER SSANG GIYEOG;;;;
 3133;HANGUL LETTER KIYEOK-SIOS;Lo;0;L;<compat> 11AA;;;;N;HANGUL LETTER GIYEOG SIOS;;;;
@@ -12016,7 +12052,7 @@
 4DFE;HEXAGRAM FOR AFTER COMPLETION;So;0;ON;;;;;N;;;;;
 4DFF;HEXAGRAM FOR BEFORE COMPLETION;So;0;ON;;;;;N;;;;;
 4E00;<CJK Ideograph, First>;Lo;0;L;;;;;N;;;;;
-9FD5;<CJK Ideograph, Last>;Lo;0;L;;;;;N;;;;;
+9FEA;<CJK Ideograph, Last>;Lo;0;L;;;;;N;;;;;
 A000;YI SYLLABLE IT;Lo;0;L;;;;;N;;;;;
 A001;YI SYLLABLE IX;Lo;0;L;;;;;N;;;;;
 A002;YI SYLLABLE I;Lo;0;L;;;;;N;;;;;
@@ -17093,6 +17129,9 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 10321;OLD ITALIC NUMERAL FIVE;No;0;L;;;;5;N;;;;;
 10322;OLD ITALIC NUMERAL TEN;No;0;L;;;;10;N;;;;;
 10323;OLD ITALIC NUMERAL FIFTY;No;0;L;;;;50;N;;;;;
+1032D;OLD ITALIC LETTER YE;Lo;0;L;;;;;N;;;;;
+1032E;OLD ITALIC LETTER NORTHERN TSE;Lo;0;L;;;;;N;;;;;
+1032F;OLD ITALIC LETTER SOUTHERN TSE;Lo;0;L;;;;;N;;;;;
 10330;GOTHIC LETTER AHSA;Lo;0;L;;;;;N;;;;;
 10331;GOTHIC LETTER BAIRKAN;Lo;0;L;;;;;N;;;;;
 10332;GOTHIC LETTER GIBA;Lo;0;L;;;;;N;;;;;
@@ -20068,6 +20107,158 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 118F1;WARANG CITI NUMBER EIGHTY;No;0;L;;;;80;N;;;;;
 118F2;WARANG CITI NUMBER NINETY;No;0;L;;;;90;N;;;;;
 118FF;WARANG CITI OM;Lo;0;L;;;;;N;;;;;
+11A00;ZANABAZAR SQUARE LETTER A;Lo;0;L;;;;;N;;;;;
+11A01;ZANABAZAR SQUARE VOWEL SIGN I;Mn;0;NSM;;;;;N;;;;;
+11A02;ZANABAZAR SQUARE VOWEL SIGN UE;Mn;0;NSM;;;;;N;;;;;
+11A03;ZANABAZAR SQUARE VOWEL SIGN U;Mn;0;NSM;;;;;N;;;;;
+11A04;ZANABAZAR SQUARE VOWEL SIGN E;Mn;0;NSM;;;;;N;;;;;
+11A05;ZANABAZAR SQUARE VOWEL SIGN OE;Mn;0;NSM;;;;;N;;;;;
+11A06;ZANABAZAR SQUARE VOWEL SIGN O;Mn;0;NSM;;;;;N;;;;;
+11A07;ZANABAZAR SQUARE VOWEL SIGN AI;Mc;0;L;;;;;N;;;;;
+11A08;ZANABAZAR SQUARE VOWEL SIGN AU;Mc;0;L;;;;;N;;;;;
+11A09;ZANABAZAR SQUARE VOWEL SIGN REVERSED I;Mn;0;NSM;;;;;N;;;;;
+11A0A;ZANABAZAR SQUARE VOWEL LENGTH MARK;Mn;0;NSM;;;;;N;;;;;
+11A0B;ZANABAZAR SQUARE LETTER KA;Lo;0;L;;;;;N;;;;;
+11A0C;ZANABAZAR SQUARE LETTER KHA;Lo;0;L;;;;;N;;;;;
+11A0D;ZANABAZAR SQUARE LETTER GA;Lo;0;L;;;;;N;;;;;
+11A0E;ZANABAZAR SQUARE LETTER GHA;Lo;0;L;;;;;N;;;;;
+11A0F;ZANABAZAR SQUARE LETTER NGA;Lo;0;L;;;;;N;;;;;
+11A10;ZANABAZAR SQUARE LETTER CA;Lo;0;L;;;;;N;;;;;
+11A11;ZANABAZAR SQUARE LETTER CHA;Lo;0;L;;;;;N;;;;;
+11A12;ZANABAZAR SQUARE LETTER JA;Lo;0;L;;;;;N;;;;;
+11A13;ZANABAZAR SQUARE LETTER NYA;Lo;0;L;;;;;N;;;;;
+11A14;ZANABAZAR SQUARE LETTER TTA;Lo;0;L;;;;;N;;;;;
+11A15;ZANABAZAR SQUARE LETTER TTHA;Lo;0;L;;;;;N;;;;;
+11A16;ZANABAZAR SQUARE LETTER DDA;Lo;0;L;;;;;N;;;;;
+11A17;ZANABAZAR SQUARE LETTER DDHA;Lo;0;L;;;;;N;;;;;
+11A18;ZANABAZAR SQUARE LETTER NNA;Lo;0;L;;;;;N;;;;;
+11A19;ZANABAZAR SQUARE LETTER TA;Lo;0;L;;;;;N;;;;;
+11A1A;ZANABAZAR SQUARE LETTER THA;Lo;0;L;;;;;N;;;;;
+11A1B;ZANABAZAR SQUARE LETTER DA;Lo;0;L;;;;;N;;;;;
+11A1C;ZANABAZAR SQUARE LETTER DHA;Lo;0;L;;;;;N;;;;;
+11A1D;ZANABAZAR SQUARE LETTER NA;Lo;0;L;;;;;N;;;;;
+11A1E;ZANABAZAR SQUARE LETTER PA;Lo;0;L;;;;;N;;;;;
+11A1F;ZANABAZAR SQUARE LETTER PHA;Lo;0;L;;;;;N;;;;;
+11A20;ZANABAZAR SQUARE LETTER BA;Lo;0;L;;;;;N;;;;;
+11A21;ZANABAZAR SQUARE LETTER BHA;Lo;0;L;;;;;N;;;;;
+11A22;ZANABAZAR SQUARE LETTER MA;Lo;0;L;;;;;N;;;;;
+11A23;ZANABAZAR SQUARE LETTER TSA;Lo;0;L;;;;;N;;;;;
+11A24;ZANABAZAR SQUARE LETTER TSHA;Lo;0;L;;;;;N;;;;;
+11A25;ZANABAZAR SQUARE LETTER DZA;Lo;0;L;;;;;N;;;;;
+11A26;ZANABAZAR SQUARE LETTER DZHA;Lo;0;L;;;;;N;;;;;
+11A27;ZANABAZAR SQUARE LETTER ZHA;Lo;0;L;;;;;N;;;;;
+11A28;ZANABAZAR SQUARE LETTER ZA;Lo;0;L;;;;;N;;;;;
+11A29;ZANABAZAR SQUARE LETTER -A;Lo;0;L;;;;;N;;;;;
+11A2A;ZANABAZAR SQUARE LETTER YA;Lo;0;L;;;;;N;;;;;
+11A2B;ZANABAZAR SQUARE LETTER RA;Lo;0;L;;;;;N;;;;;
+11A2C;ZANABAZAR SQUARE LETTER LA;Lo;0;L;;;;;N;;;;;
+11A2D;ZANABAZAR SQUARE LETTER VA;Lo;0;L;;;;;N;;;;;
+11A2E;ZANABAZAR SQUARE LETTER SHA;Lo;0;L;;;;;N;;;;;
+11A2F;ZANABAZAR SQUARE LETTER SSA;Lo;0;L;;;;;N;;;;;
+11A30;ZANABAZAR SQUARE LETTER SA;Lo;0;L;;;;;N;;;;;
+11A31;ZANABAZAR SQUARE LETTER HA;Lo;0;L;;;;;N;;;;;
+11A32;ZANABAZAR SQUARE LETTER KSSA;Lo;0;L;;;;;N;;;;;
+11A33;ZANABAZAR SQUARE FINAL CONSONANT MARK;Mn;0;NSM;;;;;N;;;;;
+11A34;ZANABAZAR SQUARE SIGN VIRAMA;Mn;9;NSM;;;;;N;;;;;
+11A35;ZANABAZAR SQUARE SIGN CANDRABINDU;Mn;0;NSM;;;;;N;;;;;
+11A36;ZANABAZAR SQUARE SIGN CANDRABINDU WITH ORNAMENT;Mn;0;NSM;;;;;N;;;;;
+11A37;ZANABAZAR SQUARE SIGN CANDRA WITH ORNAMENT;Mn;0;NSM;;;;;N;;;;;
+11A38;ZANABAZAR SQUARE SIGN ANUSVARA;Mn;0;NSM;;;;;N;;;;;
+11A39;ZANABAZAR SQUARE SIGN VISARGA;Mc;0;L;;;;;N;;;;;
+11A3A;ZANABAZAR SQUARE CLUSTER-INITIAL LETTER RA;Lo;0;L;;;;;N;;;;;
+11A3B;ZANABAZAR SQUARE CLUSTER-FINAL LETTER YA;Mn;0;NSM;;;;;N;;;;;
+11A3C;ZANABAZAR SQUARE CLUSTER-FINAL LETTER RA;Mn;0;NSM;;;;;N;;;;;
+11A3D;ZANABAZAR SQUARE CLUSTER-FINAL LETTER LA;Mn;0;NSM;;;;;N;;;;;
+11A3E;ZANABAZAR SQUARE CLUSTER-FINAL LETTER VA;Mn;0;NSM;;;;;N;;;;;
+11A3F;ZANABAZAR SQUARE INITIAL HEAD MARK;Po;0;L;;;;;N;;;;;
+11A40;ZANABAZAR SQUARE CLOSING HEAD MARK;Po;0;L;;;;;N;;;;;
+11A41;ZANABAZAR SQUARE MARK TSHEG;Po;0;L;;;;;N;;;;;
+11A42;ZANABAZAR SQUARE MARK SHAD;Po;0;L;;;;;N;;;;;
+11A43;ZANABAZAR SQUARE MARK DOUBLE SHAD;Po;0;L;;;;;N;;;;;
+11A44;ZANABAZAR SQUARE MARK LONG TSHEG;Po;0;L;;;;;N;;;;;
+11A45;ZANABAZAR SQUARE INITIAL DOUBLE-LINED HEAD MARK;Po;0;L;;;;;N;;;;;
+11A46;ZANABAZAR SQUARE CLOSING DOUBLE-LINED HEAD MARK;Po;0;L;;;;;N;;;;;
+11A47;ZANABAZAR SQUARE SUBJOINER;Mn;9;NSM;;;;;N;;;;;
+11A50;SOYOMBO LETTER A;Lo;0;L;;;;;N;;;;;
+11A51;SOYOMBO VOWEL SIGN I;Mn;0;NSM;;;;;N;;;;;
+11A52;SOYOMBO VOWEL SIGN UE;Mn;0;NSM;;;;;N;;;;;
+11A53;SOYOMBO VOWEL SIGN U;Mn;0;NSM;;;;;N;;;;;
+11A54;SOYOMBO VOWEL SIGN E;Mn;0;NSM;;;;;N;;;;;
+11A55;SOYOMBO VOWEL SIGN O;Mn;0;NSM;;;;;N;;;;;
+11A56;SOYOMBO VOWEL SIGN OE;Mn;0;NSM;;;;;N;;;;;
+11A57;SOYOMBO VOWEL SIGN AI;Mc;0;L;;;;;N;;;;;
+11A58;SOYOMBO VOWEL SIGN AU;Mc;0;L;;;;;N;;;;;
+11A59;SOYOMBO VOWEL SIGN VOCALIC R;Mn;0;NSM;;;;;N;;;;;
+11A5A;SOYOMBO VOWEL SIGN VOCALIC L;Mn;0;NSM;;;;;N;;;;;
+11A5B;SOYOMBO VOWEL LENGTH MARK;Mn;0;NSM;;;;;N;;;;;
+11A5C;SOYOMBO LETTER KA;Lo;0;L;;;;;N;;;;;
+11A5D;SOYOMBO LETTER KHA;Lo;0;L;;;;;N;;;;;
+11A5E;SOYOMBO LETTER GA;Lo;0;L;;;;;N;;;;;
+11A5F;SOYOMBO LETTER GHA;Lo;0;L;;;;;N;;;;;
+11A60;SOYOMBO LETTER NGA;Lo;0;L;;;;;N;;;;;
+11A61;SOYOMBO LETTER CA;Lo;0;L;;;;;N;;;;;
+11A62;SOYOMBO LETTER CHA;Lo;0;L;;;;;N;;;;;
+11A63;SOYOMBO LETTER JA;Lo;0;L;;;;;N;;;;;
+11A64;SOYOMBO LETTER JHA;Lo;0;L;;;;;N;;;;;
+11A65;SOYOMBO LETTER NYA;Lo;0;L;;;;;N;;;;;
+11A66;SOYOMBO LETTER TTA;Lo;0;L;;;;;N;;;;;
+11A67;SOYOMBO LETTER TTHA;Lo;0;L;;;;;N;;;;;
+11A68;SOYOMBO LETTER DDA;Lo;0;L;;;;;N;;;;;
+11A69;SOYOMBO LETTER DDHA;Lo;0;L;;;;;N;;;;;
+11A6A;SOYOMBO LETTER NNA;Lo;0;L;;;;;N;;;;;
+11A6B;SOYOMBO LETTER TA;Lo;0;L;;;;;N;;;;;
+11A6C;SOYOMBO LETTER THA;Lo;0;L;;;;;N;;;;;
+11A6D;SOYOMBO LETTER DA;Lo;0;L;;;;;N;;;;;
+11A6E;SOYOMBO LETTER DHA;Lo;0;L;;;;;N;;;;;
+11A6F;SOYOMBO LETTER NA;Lo;0;L;;;;;N;;;;;
+11A70;SOYOMBO LETTER PA;Lo;0;L;;;;;N;;;;;
+11A71;SOYOMBO LETTER PHA;Lo;0;L;;;;;N;;;;;
+11A72;SOYOMBO LETTER BA;Lo;0;L;;;;;N;;;;;
+11A73;SOYOMBO LETTER BHA;Lo;0;L;;;;;N;;;;;
+11A74;SOYOMBO LETTER MA;Lo;0;L;;;;;N;;;;;
+11A75;SOYOMBO LETTER TSA;Lo;0;L;;;;;N;;;;;
+11A76;SOYOMBO LETTER TSHA;Lo;0;L;;;;;N;;;;;
+11A77;SOYOMBO LETTER DZA;Lo;0;L;;;;;N;;;;;
+11A78;SOYOMBO LETTER ZHA;Lo;0;L;;;;;N;;;;;
+11A79;SOYOMBO LETTER ZA;Lo;0;L;;;;;N;;;;;
+11A7A;SOYOMBO LETTER -A;Lo;0;L;;;;;N;;;;;
+11A7B;SOYOMBO LETTER YA;Lo;0;L;;;;;N;;;;;
+11A7C;SOYOMBO LETTER RA;Lo;0;L;;;;;N;;;;;
+11A7D;SOYOMBO LETTER LA;Lo;0;L;;;;;N;;;;;
+11A7E;SOYOMBO LETTER VA;Lo;0;L;;;;;N;;;;;
+11A7F;SOYOMBO LETTER SHA;Lo;0;L;;;;;N;;;;;
+11A80;SOYOMBO LETTER SSA;Lo;0;L;;;;;N;;;;;
+11A81;SOYOMBO LETTER SA;Lo;0;L;;;;;N;;;;;
+11A82;SOYOMBO LETTER HA;Lo;0;L;;;;;N;;;;;
+11A83;SOYOMBO LETTER KSSA;Lo;0;L;;;;;N;;;;;
+11A86;SOYOMBO CLUSTER-INITIAL LETTER RA;Lo;0;L;;;;;N;;;;;
+11A87;SOYOMBO CLUSTER-INITIAL LETTER LA;Lo;0;L;;;;;N;;;;;
+11A88;SOYOMBO CLUSTER-INITIAL LETTER SHA;Lo;0;L;;;;;N;;;;;
+11A89;SOYOMBO CLUSTER-INITIAL LETTER SA;Lo;0;L;;;;;N;;;;;
+11A8A;SOYOMBO FINAL CONSONANT SIGN G;Mn;0;NSM;;;;;N;;;;;
+11A8B;SOYOMBO FINAL CONSONANT SIGN K;Mn;0;NSM;;;;;N;;;;;
+11A8C;SOYOMBO FINAL CONSONANT SIGN NG;Mn;0;NSM;;;;;N;;;;;
+11A8D;SOYOMBO FINAL CONSONANT SIGN D;Mn;0;NSM;;;;;N;;;;;
+11A8E;SOYOMBO FINAL CONSONANT SIGN N;Mn;0;NSM;;;;;N;;;;;
+11A8F;SOYOMBO FINAL CONSONANT SIGN B;Mn;0;NSM;;;;;N;;;;;
+11A90;SOYOMBO FINAL CONSONANT SIGN M;Mn;0;NSM;;;;;N;;;;;
+11A91;SOYOMBO FINAL CONSONANT SIGN R;Mn;0;NSM;;;;;N;;;;;
+11A92;SOYOMBO FINAL CONSONANT SIGN L;Mn;0;NSM;;;;;N;;;;;
+11A93;SOYOMBO FINAL CONSONANT SIGN SH;Mn;0;NSM;;;;;N;;;;;
+11A94;SOYOMBO FINAL CONSONANT SIGN S;Mn;0;NSM;;;;;N;;;;;
+11A95;SOYOMBO FINAL CONSONANT SIGN -A;Mn;0;NSM;;;;;N;;;;;
+11A96;SOYOMBO SIGN ANUSVARA;Mn;0;NSM;;;;;N;;;;;
+11A97;SOYOMBO SIGN VISARGA;Mc;0;L;;;;;N;;;;;
+11A98;SOYOMBO GEMINATION MARK;Mn;0;NSM;;;;;N;;;;;
+11A99;SOYOMBO SUBJOINER;Mn;9;NSM;;;;;N;;;;;
+11A9A;SOYOMBO MARK TSHEG;Po;0;L;;;;;N;;;;;
+11A9B;SOYOMBO MARK SHAD;Po;0;L;;;;;N;;;;;
+11A9C;SOYOMBO MARK DOUBLE SHAD;Po;0;L;;;;;N;;;;;
+11A9E;SOYOMBO HEAD MARK WITH MOON AND SUN AND TRIPLE FLAME;Po;0;L;;;;;N;;;;;
+11A9F;SOYOMBO HEAD MARK WITH MOON AND SUN AND FLAME;Po;0;L;;;;;N;;;;;
+11AA0;SOYOMBO HEAD MARK WITH MOON AND SUN;Po;0;L;;;;;N;;;;;
+11AA1;SOYOMBO TERMINAL MARK-1;Po;0;L;;;;;N;;;;;
+11AA2;SOYOMBO TERMINAL MARK-2;Po;0;L;;;;;N;;;;;
 11AC0;PAU CIN HAU LETTER PA;Lo;0;L;;;;;N;;;;;
 11AC1;PAU CIN HAU LETTER KA;Lo;0;L;;;;;N;;;;;
 11AC2;PAU CIN HAU LETTER LA;Lo;0;L;;;;;N;;;;;
@@ -20290,6 +20481,81 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 11CB4;MARCHEN VOWEL SIGN O;Mc;0;L;;;;;N;;;;;
 11CB5;MARCHEN SIGN ANUSVARA;Mn;0;NSM;;;;;N;;;;;
 11CB6;MARCHEN SIGN CANDRABINDU;Mn;0;NSM;;;;;N;;;;;
+11D00;MASARAM GONDI LETTER A;Lo;0;L;;;;;N;;;;;
+11D01;MASARAM GONDI LETTER AA;Lo;0;L;;;;;N;;;;;
+11D02;MASARAM GONDI LETTER I;Lo;0;L;;;;;N;;;;;
+11D03;MASARAM GONDI LETTER II;Lo;0;L;;;;;N;;;;;
+11D04;MASARAM GONDI LETTER U;Lo;0;L;;;;;N;;;;;
+11D05;MASARAM GONDI LETTER UU;Lo;0;L;;;;;N;;;;;
+11D06;MASARAM GONDI LETTER E;Lo;0;L;;;;;N;;;;;
+11D08;MASARAM GONDI LETTER AI;Lo;0;L;;;;;N;;;;;
+11D09;MASARAM GONDI LETTER O;Lo;0;L;;;;;N;;;;;
+11D0B;MASARAM GONDI LETTER AU;Lo;0;L;;;;;N;;;;;
+11D0C;MASARAM GONDI LETTER KA;Lo;0;L;;;;;N;;;;;
+11D0D;MASARAM GONDI LETTER KHA;Lo;0;L;;;;;N;;;;;
+11D0E;MASARAM GONDI LETTER GA;Lo;0;L;;;;;N;;;;;
+11D0F;MASARAM GONDI LETTER GHA;Lo;0;L;;;;;N;;;;;
+11D10;MASARAM GONDI LETTER NGA;Lo;0;L;;;;;N;;;;;
+11D11;MASARAM GONDI LETTER CA;Lo;0;L;;;;;N;;;;;
+11D12;MASARAM GONDI LETTER CHA;Lo;0;L;;;;;N;;;;;
+11D13;MASARAM GONDI LETTER JA;Lo;0;L;;;;;N;;;;;
+11D14;MASARAM GONDI LETTER JHA;Lo;0;L;;;;;N;;;;;
+11D15;MASARAM GONDI LETTER NYA;Lo;0;L;;;;;N;;;;;
+11D16;MASARAM GONDI LETTER TTA;Lo;0;L;;;;;N;;;;;
+11D17;MASARAM GONDI LETTER TTHA;Lo;0;L;;;;;N;;;;;
+11D18;MASARAM GONDI LETTER DDA;Lo;0;L;;;;;N;;;;;
+11D19;MASARAM GONDI LETTER DDHA;Lo;0;L;;;;;N;;;;;
+11D1A;MASARAM GONDI LETTER NNA;Lo;0;L;;;;;N;;;;;
+11D1B;MASARAM GONDI LETTER TA;Lo;0;L;;;;;N;;;;;
+11D1C;MASARAM GONDI LETTER THA;Lo;0;L;;;;;N;;;;;
+11D1D;MASARAM GONDI LETTER DA;Lo;0;L;;;;;N;;;;;
+11D1E;MASARAM GONDI LETTER DHA;Lo;0;L;;;;;N;;;;;
+11D1F;MASARAM GONDI LETTER NA;Lo;0;L;;;;;N;;;;;
+11D20;MASARAM GONDI LETTER PA;Lo;0;L;;;;;N;;;;;
+11D21;MASARAM GONDI LETTER PHA;Lo;0;L;;;;;N;;;;;
+11D22;MASARAM GONDI LETTER BA;Lo;0;L;;;;;N;;;;;
+11D23;MASARAM GONDI LETTER BHA;Lo;0;L;;;;;N;;;;;
+11D24;MASARAM GONDI LETTER MA;Lo;0;L;;;;;N;;;;;
+11D25;MASARAM GONDI LETTER YA;Lo;0;L;;;;;N;;;;;
+11D26;MASARAM GONDI LETTER RA;Lo;0;L;;;;;N;;;;;
+11D27;MASARAM GONDI LETTER LA;Lo;0;L;;;;;N;;;;;
+11D28;MASARAM GONDI LETTER VA;Lo;0;L;;;;;N;;;;;
+11D29;MASARAM GONDI LETTER SHA;Lo;0;L;;;;;N;;;;;
+11D2A;MASARAM GONDI LETTER SSA;Lo;0;L;;;;;N;;;;;
+11D2B;MASARAM GONDI LETTER SA;Lo;0;L;;;;;N;;;;;
+11D2C;MASARAM GONDI LETTER HA;Lo;0;L;;;;;N;;;;;
+11D2D;MASARAM GONDI LETTER LLA;Lo;0;L;;;;;N;;;;;
+11D2E;MASARAM GONDI LETTER KSSA;Lo;0;L;;;;;N;;;;;
+11D2F;MASARAM GONDI LETTER JNYA;Lo;0;L;;;;;N;;;;;
+11D30;MASARAM GONDI LETTER TRA;Lo;0;L;;;;;N;;;;;
+11D31;MASARAM GONDI VOWEL SIGN AA;Mn;0;NSM;;;;;N;;;;;
+11D32;MASARAM GONDI VOWEL SIGN I;Mn;0;NSM;;;;;N;;;;;
+11D33;MASARAM GONDI VOWEL SIGN II;Mn;0;NSM;;;;;N;;;;;
+11D34;MASARAM GONDI VOWEL SIGN U;Mn;0;NSM;;;;;N;;;;;
+11D35;MASARAM GONDI VOWEL SIGN UU;Mn;0;NSM;;;;;N;;;;;
+11D36;MASARAM GONDI VOWEL SIGN VOCALIC R;Mn;0;NSM;;;;;N;;;;;
+11D3A;MASARAM GONDI VOWEL SIGN E;Mn;0;NSM;;;;;N;;;;;
+11D3C;MASARAM GONDI VOWEL SIGN AI;Mn;0;NSM;;;;;N;;;;;
+11D3D;MASARAM GONDI VOWEL SIGN O;Mn;0;NSM;;;;;N;;;;;
+11D3F;MASARAM GONDI VOWEL SIGN AU;Mn;0;NSM;;;;;N;;;;;
+11D40;MASARAM GONDI SIGN ANUSVARA;Mn;0;NSM;;;;;N;;;;;
+11D41;MASARAM GONDI SIGN VISARGA;Mn;0;NSM;;;;;N;;;;;
+11D42;MASARAM GONDI SIGN NUKTA;Mn;7;NSM;;;;;N;;;;;
+11D43;MASARAM GONDI SIGN CANDRA;Mn;0;NSM;;;;;N;;;;;
+11D44;MASARAM GONDI SIGN HALANTA;Mn;9;NSM;;;;;N;;;;;
+11D45;MASARAM GONDI VIRAMA;Mn;9;NSM;;;;;N;;;;;
+11D46;MASARAM GONDI REPHA;Lo;0;L;;;;;N;;;;;
+11D47;MASARAM GONDI RA-KARA;Mn;0;NSM;;;;;N;;;;;
+11D50;MASARAM GONDI DIGIT ZERO;Nd;0;L;;0;0;0;N;;;;;
+11D51;MASARAM GONDI DIGIT ONE;Nd;0;L;;1;1;1;N;;;;;
+11D52;MASARAM GONDI DIGIT TWO;Nd;0;L;;2;2;2;N;;;;;
+11D53;MASARAM GONDI DIGIT THREE;Nd;0;L;;3;3;3;N;;;;;
+11D54;MASARAM GONDI DIGIT FOUR;Nd;0;L;;4;4;4;N;;;;;
+11D55;MASARAM GONDI DIGIT FIVE;Nd;0;L;;5;5;5;N;;;;;
+11D56;MASARAM GONDI DIGIT SIX;Nd;0;L;;6;6;6;N;;;;;
+11D57;MASARAM GONDI DIGIT SEVEN;Nd;0;L;;7;7;7;N;;;;;
+11D58;MASARAM GONDI DIGIT EIGHT;Nd;0;L;;8;8;8;N;;;;;
+11D59;MASARAM GONDI DIGIT NINE;Nd;0;L;;9;9;9;N;;;;;
 12000;CUNEIFORM SIGN A;Lo;0;L;;;;;N;;;;;
 12001;CUNEIFORM SIGN A TIMES A;Lo;0;L;;;;;N;;;;;
 12002;CUNEIFORM SIGN A TIMES BAD;Lo;0;L;;;;;N;;;;;
@@ -24087,6 +24353,7 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 16F9E;MIAO LETTER REFORMED TONE-6;Lm;0;L;;;;;N;;;;;
 16F9F;MIAO LETTER REFORMED TONE-8;Lm;0;L;;;;;N;;;;;
 16FE0;TANGUT ITERATION MARK;Lm;0;L;;;;;N;;;;;
+16FE1;NUSHU ITERATION MARK;Lm;0;L;;;;;N;;;;;
 17000;<Tangut Ideograph, First>;Lo;0;L;;;;;N;;;;;
 187EC;<Tangut Ideograph, Last>;Lo;0;L;;;;;N;;;;;
 18800;TANGUT COMPONENT-001;Lo;0;L;;;;;N;;;;;
@@ -24846,6 +25113,687 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 18AF2;TANGUT COMPONENT-755;Lo;0;L;;;;;N;;;;;
 1B000;KATAKANA LETTER ARCHAIC E;Lo;0;L;;;;;N;;;;;
 1B001;HIRAGANA LETTER ARCHAIC YE;Lo;0;L;;;;;N;;;;;
+1B002;HENTAIGANA LETTER A-1;Lo;0;L;;;;;N;;;;;
+1B003;HENTAIGANA LETTER A-2;Lo;0;L;;;;;N;;;;;
+1B004;HENTAIGANA LETTER A-3;Lo;0;L;;;;;N;;;;;
+1B005;HENTAIGANA LETTER A-WO;Lo;0;L;;;;;N;;;;;
+1B006;HENTAIGANA LETTER I-1;Lo;0;L;;;;;N;;;;;
+1B007;HENTAIGANA LETTER I-2;Lo;0;L;;;;;N;;;;;
+1B008;HENTAIGANA LETTER I-3;Lo;0;L;;;;;N;;;;;
+1B009;HENTAIGANA LETTER I-4;Lo;0;L;;;;;N;;;;;
+1B00A;HENTAIGANA LETTER U-1;Lo;0;L;;;;;N;;;;;
+1B00B;HENTAIGANA LETTER U-2;Lo;0;L;;;;;N;;;;;
+1B00C;HENTAIGANA LETTER U-3;Lo;0;L;;;;;N;;;;;
+1B00D;HENTAIGANA LETTER U-4;Lo;0;L;;;;;N;;;;;
+1B00E;HENTAIGANA LETTER U-5;Lo;0;L;;;;;N;;;;;
+1B00F;HENTAIGANA LETTER E-2;Lo;0;L;;;;;N;;;;;
+1B010;HENTAIGANA LETTER E-3;Lo;0;L;;;;;N;;;;;
+1B011;HENTAIGANA LETTER E-4;Lo;0;L;;;;;N;;;;;
+1B012;HENTAIGANA LETTER E-5;Lo;0;L;;;;;N;;;;;
+1B013;HENTAIGANA LETTER E-6;Lo;0;L;;;;;N;;;;;
+1B014;HENTAIGANA LETTER O-1;Lo;0;L;;;;;N;;;;;
+1B015;HENTAIGANA LETTER O-2;Lo;0;L;;;;;N;;;;;
+1B016;HENTAIGANA LETTER O-3;Lo;0;L;;;;;N;;;;;
+1B017;HENTAIGANA LETTER KA-1;Lo;0;L;;;;;N;;;;;
+1B018;HENTAIGANA LETTER KA-2;Lo;0;L;;;;;N;;;;;
+1B019;HENTAIGANA LETTER KA-3;Lo;0;L;;;;;N;;;;;
+1B01A;HENTAIGANA LETTER KA-4;Lo;0;L;;;;;N;;;;;
+1B01B;HENTAIGANA LETTER KA-5;Lo;0;L;;;;;N;;;;;
+1B01C;HENTAIGANA LETTER KA-6;Lo;0;L;;;;;N;;;;;
+1B01D;HENTAIGANA LETTER KA-7;Lo;0;L;;;;;N;;;;;
+1B01E;HENTAIGANA LETTER KA-8;Lo;0;L;;;;;N;;;;;
+1B01F;HENTAIGANA LETTER KA-9;Lo;0;L;;;;;N;;;;;
+1B020;HENTAIGANA LETTER KA-10;Lo;0;L;;;;;N;;;;;
+1B021;HENTAIGANA LETTER KA-11;Lo;0;L;;;;;N;;;;;
+1B022;HENTAIGANA LETTER KA-KE;Lo;0;L;;;;;N;;;;;
+1B023;HENTAIGANA LETTER KI-1;Lo;0;L;;;;;N;;;;;
+1B024;HENTAIGANA LETTER KI-2;Lo;0;L;;;;;N;;;;;
+1B025;HENTAIGANA LETTER KI-3;Lo;0;L;;;;;N;;;;;
+1B026;HENTAIGANA LETTER KI-4;Lo;0;L;;;;;N;;;;;
+1B027;HENTAIGANA LETTER KI-5;Lo;0;L;;;;;N;;;;;
+1B028;HENTAIGANA LETTER KI-6;Lo;0;L;;;;;N;;;;;
+1B029;HENTAIGANA LETTER KI-7;Lo;0;L;;;;;N;;;;;
+1B02A;HENTAIGANA LETTER KI-8;Lo;0;L;;;;;N;;;;;
+1B02B;HENTAIGANA LETTER KU-1;Lo;0;L;;;;;N;;;;;
+1B02C;HENTAIGANA LETTER KU-2;Lo;0;L;;;;;N;;;;;
+1B02D;HENTAIGANA LETTER KU-3;Lo;0;L;;;;;N;;;;;
+1B02E;HENTAIGANA LETTER KU-4;Lo;0;L;;;;;N;;;;;
+1B02F;HENTAIGANA LETTER KU-5;Lo;0;L;;;;;N;;;;;
+1B030;HENTAIGANA LETTER KU-6;Lo;0;L;;;;;N;;;;;
+1B031;HENTAIGANA LETTER KU-7;Lo;0;L;;;;;N;;;;;
+1B032;HENTAIGANA LETTER KE-1;Lo;0;L;;;;;N;;;;;
+1B033;HENTAIGANA LETTER KE-2;Lo;0;L;;;;;N;;;;;
+1B034;HENTAIGANA LETTER KE-3;Lo;0;L;;;;;N;;;;;
+1B035;HENTAIGANA LETTER KE-4;Lo;0;L;;;;;N;;;;;
+1B036;HENTAIGANA LETTER KE-5;Lo;0;L;;;;;N;;;;;
+1B037;HENTAIGANA LETTER KE-6;Lo;0;L;;;;;N;;;;;
+1B038;HENTAIGANA LETTER KO-1;Lo;0;L;;;;;N;;;;;
+1B039;HENTAIGANA LETTER KO-2;Lo;0;L;;;;;N;;;;;
+1B03A;HENTAIGANA LETTER KO-3;Lo;0;L;;;;;N;;;;;
+1B03B;HENTAIGANA LETTER KO-KI;Lo;0;L;;;;;N;;;;;
+1B03C;HENTAIGANA LETTER SA-1;Lo;0;L;;;;;N;;;;;
+1B03D;HENTAIGANA LETTER SA-2;Lo;0;L;;;;;N;;;;;
+1B03E;HENTAIGANA LETTER SA-3;Lo;0;L;;;;;N;;;;;
+1B03F;HENTAIGANA LETTER SA-4;Lo;0;L;;;;;N;;;;;
+1B040;HENTAIGANA LETTER SA-5;Lo;0;L;;;;;N;;;;;
+1B041;HENTAIGANA LETTER SA-6;Lo;0;L;;;;;N;;;;;
+1B042;HENTAIGANA LETTER SA-7;Lo;0;L;;;;;N;;;;;
+1B043;HENTAIGANA LETTER SA-8;Lo;0;L;;;;;N;;;;;
+1B044;HENTAIGANA LETTER SI-1;Lo;0;L;;;;;N;;;;;
+1B045;HENTAIGANA LETTER SI-2;Lo;0;L;;;;;N;;;;;
+1B046;HENTAIGANA LETTER SI-3;Lo;0;L;;;;;N;;;;;
+1B047;HENTAIGANA LETTER SI-4;Lo;0;L;;;;;N;;;;;
+1B048;HENTAIGANA LETTER SI-5;Lo;0;L;;;;;N;;;;;
+1B049;HENTAIGANA LETTER SI-6;Lo;0;L;;;;;N;;;;;
+1B04A;HENTAIGANA LETTER SU-1;Lo;0;L;;;;;N;;;;;
+1B04B;HENTAIGANA LETTER SU-2;Lo;0;L;;;;;N;;;;;
+1B04C;HENTAIGANA LETTER SU-3;Lo;0;L;;;;;N;;;;;
+1B04D;HENTAIGANA LETTER SU-4;Lo;0;L;;;;;N;;;;;
+1B04E;HENTAIGANA LETTER SU-5;Lo;0;L;;;;;N;;;;;
+1B04F;HENTAIGANA LETTER SU-6;Lo;0;L;;;;;N;;;;;
+1B050;HENTAIGANA LETTER SU-7;Lo;0;L;;;;;N;;;;;
+1B051;HENTAIGANA LETTER SU-8;Lo;0;L;;;;;N;;;;;
+1B052;HENTAIGANA LETTER SE-1;Lo;0;L;;;;;N;;;;;
+1B053;HENTAIGANA LETTER SE-2;Lo;0;L;;;;;N;;;;;
+1B054;HENTAIGANA LETTER SE-3;Lo;0;L;;;;;N;;;;;
+1B055;HENTAIGANA LETTER SE-4;Lo;0;L;;;;;N;;;;;
+1B056;HENTAIGANA LETTER SE-5;Lo;0;L;;;;;N;;;;;
+1B057;HENTAIGANA LETTER SO-1;Lo;0;L;;;;;N;;;;;
+1B058;HENTAIGANA LETTER SO-2;Lo;0;L;;;;;N;;;;;
+1B059;HENTAIGANA LETTER SO-3;Lo;0;L;;;;;N;;;;;
+1B05A;HENTAIGANA LETTER SO-4;Lo;0;L;;;;;N;;;;;
+1B05B;HENTAIGANA LETTER SO-5;Lo;0;L;;;;;N;;;;;
+1B05C;HENTAIGANA LETTER SO-6;Lo;0;L;;;;;N;;;;;
+1B05D;HENTAIGANA LETTER SO-7;Lo;0;L;;;;;N;;;;;
+1B05E;HENTAIGANA LETTER TA-1;Lo;0;L;;;;;N;;;;;
+1B05F;HENTAIGANA LETTER TA-2;Lo;0;L;;;;;N;;;;;
+1B060;HENTAIGANA LETTER TA-3;Lo;0;L;;;;;N;;;;;
+1B061;HENTAIGANA LETTER TA-4;Lo;0;L;;;;;N;;;;;
+1B062;HENTAIGANA LETTER TI-1;Lo;0;L;;;;;N;;;;;
+1B063;HENTAIGANA LETTER TI-2;Lo;0;L;;;;;N;;;;;
+1B064;HENTAIGANA LETTER TI-3;Lo;0;L;;;;;N;;;;;
+1B065;HENTAIGANA LETTER TI-4;Lo;0;L;;;;;N;;;;;
+1B066;HENTAIGANA LETTER TI-5;Lo;0;L;;;;;N;;;;;
+1B067;HENTAIGANA LETTER TI-6;Lo;0;L;;;;;N;;;;;
+1B068;HENTAIGANA LETTER TI-7;Lo;0;L;;;;;N;;;;;
+1B069;HENTAIGANA LETTER TU-1;Lo;0;L;;;;;N;;;;;
+1B06A;HENTAIGANA LETTER TU-2;Lo;0;L;;;;;N;;;;;
+1B06B;HENTAIGANA LETTER TU-3;Lo;0;L;;;;;N;;;;;
+1B06C;HENTAIGANA LETTER TU-4;Lo;0;L;;;;;N;;;;;
+1B06D;HENTAIGANA LETTER TU-TO;Lo;0;L;;;;;N;;;;;
+1B06E;HENTAIGANA LETTER TE-1;Lo;0;L;;;;;N;;;;;
+1B06F;HENTAIGANA LETTER TE-2;Lo;0;L;;;;;N;;;;;
+1B070;HENTAIGANA LETTER TE-3;Lo;0;L;;;;;N;;;;;
+1B071;HENTAIGANA LETTER TE-4;Lo;0;L;;;;;N;;;;;
+1B072;HENTAIGANA LETTER TE-5;Lo;0;L;;;;;N;;;;;
+1B073;HENTAIGANA LETTER TE-6;Lo;0;L;;;;;N;;;;;
+1B074;HENTAIGANA LETTER TE-7;Lo;0;L;;;;;N;;;;;
+1B075;HENTAIGANA LETTER TE-8;Lo;0;L;;;;;N;;;;;
+1B076;HENTAIGANA LETTER TE-9;Lo;0;L;;;;;N;;;;;
+1B077;HENTAIGANA LETTER TO-1;Lo;0;L;;;;;N;;;;;
+1B078;HENTAIGANA LETTER TO-2;Lo;0;L;;;;;N;;;;;
+1B079;HENTAIGANA LETTER TO-3;Lo;0;L;;;;;N;;;;;
+1B07A;HENTAIGANA LETTER TO-4;Lo;0;L;;;;;N;;;;;
+1B07B;HENTAIGANA LETTER TO-5;Lo;0;L;;;;;N;;;;;
+1B07C;HENTAIGANA LETTER TO-6;Lo;0;L;;;;;N;;;;;
+1B07D;HENTAIGANA LETTER TO-RA;Lo;0;L;;;;;N;;;;;
+1B07E;HENTAIGANA LETTER NA-1;Lo;0;L;;;;;N;;;;;
+1B07F;HENTAIGANA LETTER NA-2;Lo;0;L;;;;;N;;;;;
+1B080;HENTAIGANA LETTER NA-3;Lo;0;L;;;;;N;;;;;
+1B081;HENTAIGANA LETTER NA-4;Lo;0;L;;;;;N;;;;;
+1B082;HENTAIGANA LETTER NA-5;Lo;0;L;;;;;N;;;;;
+1B083;HENTAIGANA LETTER NA-6;Lo;0;L;;;;;N;;;;;
+1B084;HENTAIGANA LETTER NA-7;Lo;0;L;;;;;N;;;;;
+1B085;HENTAIGANA LETTER NA-8;Lo;0;L;;;;;N;;;;;
+1B086;HENTAIGANA LETTER NA-9;Lo;0;L;;;;;N;;;;;
+1B087;HENTAIGANA LETTER NI-1;Lo;0;L;;;;;N;;;;;
+1B088;HENTAIGANA LETTER NI-2;Lo;0;L;;;;;N;;;;;
+1B089;HENTAIGANA LETTER NI-3;Lo;0;L;;;;;N;;;;;
+1B08A;HENTAIGANA LETTER NI-4;Lo;0;L;;;;;N;;;;;
+1B08B;HENTAIGANA LETTER NI-5;Lo;0;L;;;;;N;;;;;
+1B08C;HENTAIGANA LETTER NI-6;Lo;0;L;;;;;N;;;;;
+1B08D;HENTAIGANA LETTER NI-7;Lo;0;L;;;;;N;;;;;
+1B08E;HENTAIGANA LETTER NI-TE;Lo;0;L;;;;;N;;;;;
+1B08F;HENTAIGANA LETTER NU-1;Lo;0;L;;;;;N;;;;;
+1B090;HENTAIGANA LETTER NU-2;Lo;0;L;;;;;N;;;;;
+1B091;HENTAIGANA LETTER NU-3;Lo;0;L;;;;;N;;;;;
+1B092;HENTAIGANA LETTER NE-1;Lo;0;L;;;;;N;;;;;
+1B093;HENTAIGANA LETTER NE-2;Lo;0;L;;;;;N;;;;;
+1B094;HENTAIGANA LETTER NE-3;Lo;0;L;;;;;N;;;;;
+1B095;HENTAIGANA LETTER NE-4;Lo;0;L;;;;;N;;;;;
+1B096;HENTAIGANA LETTER NE-5;Lo;0;L;;;;;N;;;;;
+1B097;HENTAIGANA LETTER NE-6;Lo;0;L;;;;;N;;;;;
+1B098;HENTAIGANA LETTER NE-KO;Lo;0;L;;;;;N;;;;;
+1B099;HENTAIGANA LETTER NO-1;Lo;0;L;;;;;N;;;;;
+1B09A;HENTAIGANA LETTER NO-2;Lo;0;L;;;;;N;;;;;
+1B09B;HENTAIGANA LETTER NO-3;Lo;0;L;;;;;N;;;;;
+1B09C;HENTAIGANA LETTER NO-4;Lo;0;L;;;;;N;;;;;
+1B09D;HENTAIGANA LETTER NO-5;Lo;0;L;;;;;N;;;;;
+1B09E;HENTAIGANA LETTER HA-1;Lo;0;L;;;;;N;;;;;
+1B09F;HENTAIGANA LETTER HA-2;Lo;0;L;;;;;N;;;;;
+1B0A0;HENTAIGANA LETTER HA-3;Lo;0;L;;;;;N;;;;;
+1B0A1;HENTAIGANA LETTER HA-4;Lo;0;L;;;;;N;;;;;
+1B0A2;HENTAIGANA LETTER HA-5;Lo;0;L;;;;;N;;;;;
+1B0A3;HENTAIGANA LETTER HA-6;Lo;0;L;;;;;N;;;;;
+1B0A4;HENTAIGANA LETTER HA-7;Lo;0;L;;;;;N;;;;;
+1B0A5;HENTAIGANA LETTER HA-8;Lo;0;L;;;;;N;;;;;
+1B0A6;HENTAIGANA LETTER HA-9;Lo;0;L;;;;;N;;;;;
+1B0A7;HENTAIGANA LETTER HA-10;Lo;0;L;;;;;N;;;;;
+1B0A8;HENTAIGANA LETTER HA-11;Lo;0;L;;;;;N;;;;;
+1B0A9;HENTAIGANA LETTER HI-1;Lo;0;L;;;;;N;;;;;
+1B0AA;HENTAIGANA LETTER HI-2;Lo;0;L;;;;;N;;;;;
+1B0AB;HENTAIGANA LETTER HI-3;Lo;0;L;;;;;N;;;;;
+1B0AC;HENTAIGANA LETTER HI-4;Lo;0;L;;;;;N;;;;;
+1B0AD;HENTAIGANA LETTER HI-5;Lo;0;L;;;;;N;;;;;
+1B0AE;HENTAIGANA LETTER HI-6;Lo;0;L;;;;;N;;;;;
+1B0AF;HENTAIGANA LETTER HI-7;Lo;0;L;;;;;N;;;;;
+1B0B0;HENTAIGANA LETTER HU-1;Lo;0;L;;;;;N;;;;;
+1B0B1;HENTAIGANA LETTER HU-2;Lo;0;L;;;;;N;;;;;
+1B0B2;HENTAIGANA LETTER HU-3;Lo;0;L;;;;;N;;;;;
+1B0B3;HENTAIGANA LETTER HE-1;Lo;0;L;;;;;N;;;;;
+1B0B4;HENTAIGANA LETTER HE-2;Lo;0;L;;;;;N;;;;;
+1B0B5;HENTAIGANA LETTER HE-3;Lo;0;L;;;;;N;;;;;
+1B0B6;HENTAIGANA LETTER HE-4;Lo;0;L;;;;;N;;;;;
+1B0B7;HENTAIGANA LETTER HE-5;Lo;0;L;;;;;N;;;;;
+1B0B8;HENTAIGANA LETTER HE-6;Lo;0;L;;;;;N;;;;;
+1B0B9;HENTAIGANA LETTER HE-7;Lo;0;L;;;;;N;;;;;
+1B0BA;HENTAIGANA LETTER HO-1;Lo;0;L;;;;;N;;;;;
+1B0BB;HENTAIGANA LETTER HO-2;Lo;0;L;;;;;N;;;;;
+1B0BC;HENTAIGANA LETTER HO-3;Lo;0;L;;;;;N;;;;;
+1B0BD;HENTAIGANA LETTER HO-4;Lo;0;L;;;;;N;;;;;
+1B0BE;HENTAIGANA LETTER HO-5;Lo;0;L;;;;;N;;;;;
+1B0BF;HENTAIGANA LETTER HO-6;Lo;0;L;;;;;N;;;;;
+1B0C0;HENTAIGANA LETTER HO-7;Lo;0;L;;;;;N;;;;;
+1B0C1;HENTAIGANA LETTER HO-8;Lo;0;L;;;;;N;;;;;
+1B0C2;HENTAIGANA LETTER MA-1;Lo;0;L;;;;;N;;;;;
+1B0C3;HENTAIGANA LETTER MA-2;Lo;0;L;;;;;N;;;;;
+1B0C4;HENTAIGANA LETTER MA-3;Lo;0;L;;;;;N;;;;;
+1B0C5;HENTAIGANA LETTER MA-4;Lo;0;L;;;;;N;;;;;
+1B0C6;HENTAIGANA LETTER MA-5;Lo;0;L;;;;;N;;;;;
+1B0C7;HENTAIGANA LETTER MA-6;Lo;0;L;;;;;N;;;;;
+1B0C8;HENTAIGANA LETTER MA-7;Lo;0;L;;;;;N;;;;;
+1B0C9;HENTAIGANA LETTER MI-1;Lo;0;L;;;;;N;;;;;
+1B0CA;HENTAIGANA LETTER MI-2;Lo;0;L;;;;;N;;;;;
+1B0CB;HENTAIGANA LETTER MI-3;Lo;0;L;;;;;N;;;;;
+1B0CC;HENTAIGANA LETTER MI-4;Lo;0;L;;;;;N;;;;;
+1B0CD;HENTAIGANA LETTER MI-5;Lo;0;L;;;;;N;;;;;
+1B0CE;HENTAIGANA LETTER MI-6;Lo;0;L;;;;;N;;;;;
+1B0CF;HENTAIGANA LETTER MI-7;Lo;0;L;;;;;N;;;;;
+1B0D0;HENTAIGANA LETTER MU-1;Lo;0;L;;;;;N;;;;;
+1B0D1;HENTAIGANA LETTER MU-2;Lo;0;L;;;;;N;;;;;
+1B0D2;HENTAIGANA LETTER MU-3;Lo;0;L;;;;;N;;;;;
+1B0D3;HENTAIGANA LETTER MU-4;Lo;0;L;;;;;N;;;;;
+1B0D4;HENTAIGANA LETTER ME-1;Lo;0;L;;;;;N;;;;;
+1B0D5;HENTAIGANA LETTER ME-2;Lo;0;L;;;;;N;;;;;
+1B0D6;HENTAIGANA LETTER ME-MA;Lo;0;L;;;;;N;;;;;
+1B0D7;HENTAIGANA LETTER MO-1;Lo;0;L;;;;;N;;;;;
+1B0D8;HENTAIGANA LETTER MO-2;Lo;0;L;;;;;N;;;;;
+1B0D9;HENTAIGANA LETTER MO-3;Lo;0;L;;;;;N;;;;;
+1B0DA;HENTAIGANA LETTER MO-4;Lo;0;L;;;;;N;;;;;
+1B0DB;HENTAIGANA LETTER MO-5;Lo;0;L;;;;;N;;;;;
+1B0DC;HENTAIGANA LETTER MO-6;Lo;0;L;;;;;N;;;;;
+1B0DD;HENTAIGANA LETTER YA-1;Lo;0;L;;;;;N;;;;;
+1B0DE;HENTAIGANA LETTER YA-2;Lo;0;L;;;;;N;;;;;
+1B0DF;HENTAIGANA LETTER YA-3;Lo;0;L;;;;;N;;;;;
+1B0E0;HENTAIGANA LETTER YA-4;Lo;0;L;;;;;N;;;;;
+1B0E1;HENTAIGANA LETTER YA-5;Lo;0;L;;;;;N;;;;;
+1B0E2;HENTAIGANA LETTER YA-YO;Lo;0;L;;;;;N;;;;;
+1B0E3;HENTAIGANA LETTER YU-1;Lo;0;L;;;;;N;;;;;
+1B0E4;HENTAIGANA LETTER YU-2;Lo;0;L;;;;;N;;;;;
+1B0E5;HENTAIGANA LETTER YU-3;Lo;0;L;;;;;N;;;;;
+1B0E6;HENTAIGANA LETTER YU-4;Lo;0;L;;;;;N;;;;;
+1B0E7;HENTAIGANA LETTER YO-1;Lo;0;L;;;;;N;;;;;
+1B0E8;HENTAIGANA LETTER YO-2;Lo;0;L;;;;;N;;;;;
+1B0E9;HENTAIGANA LETTER YO-3;Lo;0;L;;;;;N;;;;;
+1B0EA;HENTAIGANA LETTER YO-4;Lo;0;L;;;;;N;;;;;
+1B0EB;HENTAIGANA LETTER YO-5;Lo;0;L;;;;;N;;;;;
+1B0EC;HENTAIGANA LETTER YO-6;Lo;0;L;;;;;N;;;;;
+1B0ED;HENTAIGANA LETTER RA-1;Lo;0;L;;;;;N;;;;;
+1B0EE;HENTAIGANA LETTER RA-2;Lo;0;L;;;;;N;;;;;
+1B0EF;HENTAIGANA LETTER RA-3;Lo;0;L;;;;;N;;;;;
+1B0F0;HENTAIGANA LETTER RA-4;Lo;0;L;;;;;N;;;;;
+1B0F1;HENTAIGANA LETTER RI-1;Lo;0;L;;;;;N;;;;;
+1B0F2;HENTAIGANA LETTER RI-2;Lo;0;L;;;;;N;;;;;
+1B0F3;HENTAIGANA LETTER RI-3;Lo;0;L;;;;;N;;;;;
+1B0F4;HENTAIGANA LETTER RI-4;Lo;0;L;;;;;N;;;;;
+1B0F5;HENTAIGANA LETTER RI-5;Lo;0;L;;;;;N;;;;;
+1B0F6;HENTAIGANA LETTER RI-6;Lo;0;L;;;;;N;;;;;
+1B0F7;HENTAIGANA LETTER RI-7;Lo;0;L;;;;;N;;;;;
+1B0F8;HENTAIGANA LETTER RU-1;Lo;0;L;;;;;N;;;;;
+1B0F9;HENTAIGANA LETTER RU-2;Lo;0;L;;;;;N;;;;;
+1B0FA;HENTAIGANA LETTER RU-3;Lo;0;L;;;;;N;;;;;
+1B0FB;HENTAIGANA LETTER RU-4;Lo;0;L;;;;;N;;;;;
+1B0FC;HENTAIGANA LETTER RU-5;Lo;0;L;;;;;N;;;;;
+1B0FD;HENTAIGANA LETTER RU-6;Lo;0;L;;;;;N;;;;;
+1B0FE;HENTAIGANA LETTER RE-1;Lo;0;L;;;;;N;;;;;
+1B0FF;HENTAIGANA LETTER RE-2;Lo;0;L;;;;;N;;;;;
+1B100;HENTAIGANA LETTER RE-3;Lo;0;L;;;;;N;;;;;
+1B101;HENTAIGANA LETTER RE-4;Lo;0;L;;;;;N;;;;;
+1B102;HENTAIGANA LETTER RO-1;Lo;0;L;;;;;N;;;;;
+1B103;HENTAIGANA LETTER RO-2;Lo;0;L;;;;;N;;;;;
+1B104;HENTAIGANA LETTER RO-3;Lo;0;L;;;;;N;;;;;
+1B105;HENTAIGANA LETTER RO-4;Lo;0;L;;;;;N;;;;;
+1B106;HENTAIGANA LETTER RO-5;Lo;0;L;;;;;N;;;;;
+1B107;HENTAIGANA LETTER RO-6;Lo;0;L;;;;;N;;;;;
+1B108;HENTAIGANA LETTER WA-1;Lo;0;L;;;;;N;;;;;
+1B109;HENTAIGANA LETTER WA-2;Lo;0;L;;;;;N;;;;;
+1B10A;HENTAIGANA LETTER WA-3;Lo;0;L;;;;;N;;;;;
+1B10B;HENTAIGANA LETTER WA-4;Lo;0;L;;;;;N;;;;;
+1B10C;HENTAIGANA LETTER WA-5;Lo;0;L;;;;;N;;;;;
+1B10D;HENTAIGANA LETTER WI-1;Lo;0;L;;;;;N;;;;;
+1B10E;HENTAIGANA LETTER WI-2;Lo;0;L;;;;;N;;;;;
+1B10F;HENTAIGANA LETTER WI-3;Lo;0;L;;;;;N;;;;;
+1B110;HENTAIGANA LETTER WI-4;Lo;0;L;;;;;N;;;;;
+1B111;HENTAIGANA LETTER WI-5;Lo;0;L;;;;;N;;;;;
+1B112;HENTAIGANA LETTER WE-1;Lo;0;L;;;;;N;;;;;
+1B113;HENTAIGANA LETTER WE-2;Lo;0;L;;;;;N;;;;;
+1B114;HENTAIGANA LETTER WE-3;Lo;0;L;;;;;N;;;;;
+1B115;HENTAIGANA LETTER WE-4;Lo;0;L;;;;;N;;;;;
+1B116;HENTAIGANA LETTER WO-1;Lo;0;L;;;;;N;;;;;
+1B117;HENTAIGANA LETTER WO-2;Lo;0;L;;;;;N;;;;;
+1B118;HENTAIGANA LETTER WO-3;Lo;0;L;;;;;N;;;;;
+1B119;HENTAIGANA LETTER WO-4;Lo;0;L;;;;;N;;;;;
+1B11A;HENTAIGANA LETTER WO-5;Lo;0;L;;;;;N;;;;;
+1B11B;HENTAIGANA LETTER WO-6;Lo;0;L;;;;;N;;;;;
+1B11C;HENTAIGANA LETTER WO-7;Lo;0;L;;;;;N;;;;;
+1B11D;HENTAIGANA LETTER N-MU-MO-1;Lo;0;L;;;;;N;;;;;
+1B11E;HENTAIGANA LETTER N-MU-MO-2;Lo;0;L;;;;;N;;;;;
+1B170;NUSHU CHARACTER-1B170;Lo;0;L;;;;;N;;;;;
+1B171;NUSHU CHARACTER-1B171;Lo;0;L;;;;;N;;;;;
+1B172;NUSHU CHARACTER-1B172;Lo;0;L;;;;;N;;;;;
+1B173;NUSHU CHARACTER-1B173;Lo;0;L;;;;;N;;;;;
+1B174;NUSHU CHARACTER-1B174;Lo;0;L;;;;;N;;;;;
+1B175;NUSHU CHARACTER-1B175;Lo;0;L;;;;;N;;;;;
+1B176;NUSHU CHARACTER-1B176;Lo;0;L;;;;;N;;;;;
+1B177;NUSHU CHARACTER-1B177;Lo;0;L;;;;;N;;;;;
+1B178;NUSHU CHARACTER-1B178;Lo;0;L;;;;;N;;;;;
+1B179;NUSHU CHARACTER-1B179;Lo;0;L;;;;;N;;;;;
+1B17A;NUSHU CHARACTER-1B17A;Lo;0;L;;;;;N;;;;;
+1B17B;NUSHU CHARACTER-1B17B;Lo;0;L;;;;;N;;;;;
+1B17C;NUSHU CHARACTER-1B17C;Lo;0;L;;;;;N;;;;;
+1B17D;NUSHU CHARACTER-1B17D;Lo;0;L;;;;;N;;;;;
+1B17E;NUSHU CHARACTER-1B17E;Lo;0;L;;;;;N;;;;;
+1B17F;NUSHU CHARACTER-1B17F;Lo;0;L;;;;;N;;;;;
+1B180;NUSHU CHARACTER-1B180;Lo;0;L;;;;;N;;;;;
+1B181;NUSHU CHARACTER-1B181;Lo;0;L;;;;;N;;;;;
+1B182;NUSHU CHARACTER-1B182;Lo;0;L;;;;;N;;;;;
+1B183;NUSHU CHARACTER-1B183;Lo;0;L;;;;;N;;;;;
+1B184;NUSHU CHARACTER-1B184;Lo;0;L;;;;;N;;;;;
+1B185;NUSHU CHARACTER-1B185;Lo;0;L;;;;;N;;;;;
+1B186;NUSHU CHARACTER-1B186;Lo;0;L;;;;;N;;;;;
+1B187;NUSHU CHARACTER-1B187;Lo;0;L;;;;;N;;;;;
+1B188;NUSHU CHARACTER-1B188;Lo;0;L;;;;;N;;;;;
+1B189;NUSHU CHARACTER-1B189;Lo;0;L;;;;;N;;;;;
+1B18A;NUSHU CHARACTER-1B18A;Lo;0;L;;;;;N;;;;;
+1B18B;NUSHU CHARACTER-1B18B;Lo;0;L;;;;;N;;;;;
+1B18C;NUSHU CHARACTER-1B18C;Lo;0;L;;;;;N;;;;;
+1B18D;NUSHU CHARACTER-1B18D;Lo;0;L;;;;;N;;;;;
+1B18E;NUSHU CHARACTER-1B18E;Lo;0;L;;;;;N;;;;;
+1B18F;NUSHU CHARACTER-1B18F;Lo;0;L;;;;;N;;;;;
+1B190;NUSHU CHARACTER-1B190;Lo;0;L;;;;;N;;;;;
+1B191;NUSHU CHARACTER-1B191;Lo;0;L;;;;;N;;;;;
+1B192;NUSHU CHARACTER-1B192;Lo;0;L;;;;;N;;;;;
+1B193;NUSHU CHARACTER-1B193;Lo;0;L;;;;;N;;;;;
+1B194;NUSHU CHARACTER-1B194;Lo;0;L;;;;;N;;;;;
+1B195;NUSHU CHARACTER-1B195;Lo;0;L;;;;;N;;;;;
+1B196;NUSHU CHARACTER-1B196;Lo;0;L;;;;;N;;;;;
+1B197;NUSHU CHARACTER-1B197;Lo;0;L;;;;;N;;;;;
+1B198;NUSHU CHARACTER-1B198;Lo;0;L;;;;;N;;;;;
+1B199;NUSHU CHARACTER-1B199;Lo;0;L;;;;;N;;;;;
+1B19A;NUSHU CHARACTER-1B19A;Lo;0;L;;;;;N;;;;;
+1B19B;NUSHU CHARACTER-1B19B;Lo;0;L;;;;;N;;;;;
+1B19C;NUSHU CHARACTER-1B19C;Lo;0;L;;;;;N;;;;;
+1B19D;NUSHU CHARACTER-1B19D;Lo;0;L;;;;;N;;;;;
+1B19E;NUSHU CHARACTER-1B19E;Lo;0;L;;;;;N;;;;;
+1B19F;NUSHU CHARACTER-1B19F;Lo;0;L;;;;;N;;;;;
+1B1A0;NUSHU CHARACTER-1B1A0;Lo;0;L;;;;;N;;;;;
+1B1A1;NUSHU CHARACTER-1B1A1;Lo;0;L;;;;;N;;;;;
+1B1A2;NUSHU CHARACTER-1B1A2;Lo;0;L;;;;;N;;;;;
+1B1A3;NUSHU CHARACTER-1B1A3;Lo;0;L;;;;;N;;;;;
+1B1A4;NUSHU CHARACTER-1B1A4;Lo;0;L;;;;;N;;;;;
+1B1A5;NUSHU CHARACTER-1B1A5;Lo;0;L;;;;;N;;;;;
+1B1A6;NUSHU CHARACTER-1B1A6;Lo;0;L;;;;;N;;;;;
+1B1A7;NUSHU CHARACTER-1B1A7;Lo;0;L;;;;;N;;;;;
+1B1A8;NUSHU CHARACTER-1B1A8;Lo;0;L;;;;;N;;;;;
+1B1A9;NUSHU CHARACTER-1B1A9;Lo;0;L;;;;;N;;;;;
+1B1AA;NUSHU CHARACTER-1B1AA;Lo;0;L;;;;;N;;;;;
+1B1AB;NUSHU CHARACTER-1B1AB;Lo;0;L;;;;;N;;;;;
+1B1AC;NUSHU CHARACTER-1B1AC;Lo;0;L;;;;;N;;;;;
+1B1AD;NUSHU CHARACTER-1B1AD;Lo;0;L;;;;;N;;;;;
+1B1AE;NUSHU CHARACTER-1B1AE;Lo;0;L;;;;;N;;;;;
+1B1AF;NUSHU CHARACTER-1B1AF;Lo;0;L;;;;;N;;;;;
+1B1B0;NUSHU CHARACTER-1B1B0;Lo;0;L;;;;;N;;;;;
+1B1B1;NUSHU CHARACTER-1B1B1;Lo;0;L;;;;;N;;;;;
+1B1B2;NUSHU CHARACTER-1B1B2;Lo;0;L;;;;;N;;;;;
+1B1B3;NUSHU CHARACTER-1B1B3;Lo;0;L;;;;;N;;;;;
+1B1B4;NUSHU CHARACTER-1B1B4;Lo;0;L;;;;;N;;;;;
+1B1B5;NUSHU CHARACTER-1B1B5;Lo;0;L;;;;;N;;;;;
+1B1B6;NUSHU CHARACTER-1B1B6;Lo;0;L;;;;;N;;;;;
+1B1B7;NUSHU CHARACTER-1B1B7;Lo;0;L;;;;;N;;;;;
+1B1B8;NUSHU CHARACTER-1B1B8;Lo;0;L;;;;;N;;;;;
+1B1B9;NUSHU CHARACTER-1B1B9;Lo;0;L;;;;;N;;;;;
+1B1BA;NUSHU CHARACTER-1B1BA;Lo;0;L;;;;;N;;;;;
+1B1BB;NUSHU CHARACTER-1B1BB;Lo;0;L;;;;;N;;;;;
+1B1BC;NUSHU CHARACTER-1B1BC;Lo;0;L;;;;;N;;;;;
+1B1BD;NUSHU CHARACTER-1B1BD;Lo;0;L;;;;;N;;;;;
+1B1BE;NUSHU CHARACTER-1B1BE;Lo;0;L;;;;;N;;;;;
+1B1BF;NUSHU CHARACTER-1B1BF;Lo;0;L;;;;;N;;;;;
+1B1C0;NUSHU CHARACTER-1B1C0;Lo;0;L;;;;;N;;;;;
+1B1C1;NUSHU CHARACTER-1B1C1;Lo;0;L;;;;;N;;;;;
+1B1C2;NUSHU CHARACTER-1B1C2;Lo;0;L;;;;;N;;;;;
+1B1C3;NUSHU CHARACTER-1B1C3;Lo;0;L;;;;;N;;;;;
+1B1C4;NUSHU CHARACTER-1B1C4;Lo;0;L;;;;;N;;;;;
+1B1C5;NUSHU CHARACTER-1B1C5;Lo;0;L;;;;;N;;;;;
+1B1C6;NUSHU CHARACTER-1B1C6;Lo;0;L;;;;;N;;;;;
+1B1C7;NUSHU CHARACTER-1B1C7;Lo;0;L;;;;;N;;;;;
+1B1C8;NUSHU CHARACTER-1B1C8;Lo;0;L;;;;;N;;;;;
+1B1C9;NUSHU CHARACTER-1B1C9;Lo;0;L;;;;;N;;;;;
+1B1CA;NUSHU CHARACTER-1B1CA;Lo;0;L;;;;;N;;;;;
+1B1CB;NUSHU CHARACTER-1B1CB;Lo;0;L;;;;;N;;;;;
+1B1CC;NUSHU CHARACTER-1B1CC;Lo;0;L;;;;;N;;;;;
+1B1CD;NUSHU CHARACTER-1B1CD;Lo;0;L;;;;;N;;;;;
+1B1CE;NUSHU CHARACTER-1B1CE;Lo;0;L;;;;;N;;;;;
+1B1CF;NUSHU CHARACTER-1B1CF;Lo;0;L;;;;;N;;;;;
+1B1D0;NUSHU CHARACTER-1B1D0;Lo;0;L;;;;;N;;;;;
+1B1D1;NUSHU CHARACTER-1B1D1;Lo;0;L;;;;;N;;;;;
+1B1D2;NUSHU CHARACTER-1B1D2;Lo;0;L;;;;;N;;;;;
+1B1D3;NUSHU CHARACTER-1B1D3;Lo;0;L;;;;;N;;;;;
+1B1D4;NUSHU CHARACTER-1B1D4;Lo;0;L;;;;;N;;;;;
+1B1D5;NUSHU CHARACTER-1B1D5;Lo;0;L;;;;;N;;;;;
+1B1D6;NUSHU CHARACTER-1B1D6;Lo;0;L;;;;;N;;;;;
+1B1D7;NUSHU CHARACTER-1B1D7;Lo;0;L;;;;;N;;;;;
+1B1D8;NUSHU CHARACTER-1B1D8;Lo;0;L;;;;;N;;;;;
+1B1D9;NUSHU CHARACTER-1B1D9;Lo;0;L;;;;;N;;;;;
+1B1DA;NUSHU CHARACTER-1B1DA;Lo;0;L;;;;;N;;;;;
+1B1DB;NUSHU CHARACTER-1B1DB;Lo;0;L;;;;;N;;;;;
+1B1DC;NUSHU CHARACTER-1B1DC;Lo;0;L;;;;;N;;;;;
+1B1DD;NUSHU CHARACTER-1B1DD;Lo;0;L;;;;;N;;;;;
+1B1DE;NUSHU CHARACTER-1B1DE;Lo;0;L;;;;;N;;;;;
+1B1DF;NUSHU CHARACTER-1B1DF;Lo;0;L;;;;;N;;;;;
+1B1E0;NUSHU CHARACTER-1B1E0;Lo;0;L;;;;;N;;;;;
+1B1E1;NUSHU CHARACTER-1B1E1;Lo;0;L;;;;;N;;;;;
+1B1E2;NUSHU CHARACTER-1B1E2;Lo;0;L;;;;;N;;;;;
+1B1E3;NUSHU CHARACTER-1B1E3;Lo;0;L;;;;;N;;;;;
+1B1E4;NUSHU CHARACTER-1B1E4;Lo;0;L;;;;;N;;;;;
+1B1E5;NUSHU CHARACTER-1B1E5;Lo;0;L;;;;;N;;;;;
+1B1E6;NUSHU CHARACTER-1B1E6;Lo;0;L;;;;;N;;;;;
+1B1E7;NUSHU CHARACTER-1B1E7;Lo;0;L;;;;;N;;;;;
+1B1E8;NUSHU CHARACTER-1B1E8;Lo;0;L;;;;;N;;;;;
+1B1E9;NUSHU CHARACTER-1B1E9;Lo;0;L;;;;;N;;;;;
+1B1EA;NUSHU CHARACTER-1B1EA;Lo;0;L;;;;;N;;;;;
+1B1EB;NUSHU CHARACTER-1B1EB;Lo;0;L;;;;;N;;;;;
+1B1EC;NUSHU CHARACTER-1B1EC;Lo;0;L;;;;;N;;;;;
+1B1ED;NUSHU CHARACTER-1B1ED;Lo;0;L;;;;;N;;;;;
+1B1EE;NUSHU CHARACTER-1B1EE;Lo;0;L;;;;;N;;;;;
+1B1EF;NUSHU CHARACTER-1B1EF;Lo;0;L;;;;;N;;;;;
+1B1F0;NUSHU CHARACTER-1B1F0;Lo;0;L;;;;;N;;;;;
+1B1F1;NUSHU CHARACTER-1B1F1;Lo;0;L;;;;;N;;;;;
+1B1F2;NUSHU CHARACTER-1B1F2;Lo;0;L;;;;;N;;;;;
+1B1F3;NUSHU CHARACTER-1B1F3;Lo;0;L;;;;;N;;;;;
+1B1F4;NUSHU CHARACTER-1B1F4;Lo;0;L;;;;;N;;;;;
+1B1F5;NUSHU CHARACTER-1B1F5;Lo;0;L;;;;;N;;;;;
+1B1F6;NUSHU CHARACTER-1B1F6;Lo;0;L;;;;;N;;;;;
+1B1F7;NUSHU CHARACTER-1B1F7;Lo;0;L;;;;;N;;;;;
+1B1F8;NUSHU CHARACTER-1B1F8;Lo;0;L;;;;;N;;;;;
+1B1F9;NUSHU CHARACTER-1B1F9;Lo;0;L;;;;;N;;;;;
+1B1FA;NUSHU CHARACTER-1B1FA;Lo;0;L;;;;;N;;;;;
+1B1FB;NUSHU CHARACTER-1B1FB;Lo;0;L;;;;;N;;;;;
+1B1FC;NUSHU CHARACTER-1B1FC;Lo;0;L;;;;;N;;;;;
+1B1FD;NUSHU CHARACTER-1B1FD;Lo;0;L;;;;;N;;;;;
+1B1FE;NUSHU CHARACTER-1B1FE;Lo;0;L;;;;;N;;;;;
+1B1FF;NUSHU CHARACTER-1B1FF;Lo;0;L;;;;;N;;;;;
+1B200;NUSHU CHARACTER-1B200;Lo;0;L;;;;;N;;;;;
+1B201;NUSHU CHARACTER-1B201;Lo;0;L;;;;;N;;;;;
+1B202;NUSHU CHARACTER-1B202;Lo;0;L;;;;;N;;;;;
+1B203;NUSHU CHARACTER-1B203;Lo;0;L;;;;;N;;;;;
+1B204;NUSHU CHARACTER-1B204;Lo;0;L;;;;;N;;;;;
+1B205;NUSHU CHARACTER-1B205;Lo;0;L;;;;;N;;;;;
+1B206;NUSHU CHARACTER-1B206;Lo;0;L;;;;;N;;;;;
+1B207;NUSHU CHARACTER-1B207;Lo;0;L;;;;;N;;;;;
+1B208;NUSHU CHARACTER-1B208;Lo;0;L;;;;;N;;;;;
+1B209;NUSHU CHARACTER-1B209;Lo;0;L;;;;;N;;;;;
+1B20A;NUSHU CHARACTER-1B20A;Lo;0;L;;;;;N;;;;;
+1B20B;NUSHU CHARACTER-1B20B;Lo;0;L;;;;;N;;;;;
+1B20C;NUSHU CHARACTER-1B20C;Lo;0;L;;;;;N;;;;;
+1B20D;NUSHU CHARACTER-1B20D;Lo;0;L;;;;;N;;;;;
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 1BC00;DUPLOYAN LETTER H;Lo;0;L;;;;;N;;;;;
 1BC01;DUPLOYAN LETTER X;Lo;0;L;;;;;N;;;;;
 1BC02;DUPLOYAN LETTER P;Lo;0;L;;;;;N;;;;;
@@ -28269,6 +29217,12 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 1F248;TORTOISE SHELL BRACKETED CJK UNIFIED IDEOGRAPH-6557;So;0;L;<compat> 3014 6557 3015;;;;N;;;;;
 1F250;CIRCLED IDEOGRAPH ADVANTAGE;So;0;L;<circle> 5F97;;;;N;;;;;
 1F251;CIRCLED IDEOGRAPH ACCEPT;So;0;L;<circle> 53EF;;;;N;;;;;
+1F260;ROUNDED SYMBOL FOR FU;So;0;ON;;;;;N;;;;;
+1F261;ROUNDED SYMBOL FOR LU;So;0;ON;;;;;N;;;;;
+1F262;ROUNDED SYMBOL FOR SHOU;So;0;ON;;;;;N;;;;;
+1F263;ROUNDED SYMBOL FOR XI;So;0;ON;;;;;N;;;;;
+1F264;ROUNDED SYMBOL FOR SHUANGXI;So;0;ON;;;;;N;;;;;
+1F265;ROUNDED SYMBOL FOR CAI;So;0;ON;;;;;N;;;;;
 1F300;CYCLONE;So;0;ON;;;;;N;;;;;
 1F301;FOGGY;So;0;ON;;;;;N;;;;;
 1F302;CLOSED UMBRELLA;So;0;ON;;;;;N;;;;;
@@ -29248,6 +30202,8 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 1F6D0;PLACE OF WORSHIP;So;0;ON;;;;;N;;;;;
 1F6D1;OCTAGONAL SIGN;So;0;ON;;;;;N;;;;;
 1F6D2;SHOPPING TROLLEY;So;0;ON;;;;;N;;;;;
+1F6D3;STUPA;So;0;ON;;;;;N;;;;;
+1F6D4;PAGODA;So;0;ON;;;;;N;;;;;
 1F6E0;HAMMER AND WRENCH;So;0;ON;;;;;N;;;;;
 1F6E1;SHIELD;So;0;ON;;;;;N;;;;;
 1F6E2;OIL DRUM;So;0;ON;;;;;N;;;;;
@@ -29268,6 +30224,8 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 1F6F4;SCOOTER;So;0;ON;;;;;N;;;;;
 1F6F5;MOTOR SCOOTER;So;0;ON;;;;;N;;;;;
 1F6F6;CANOE;So;0;ON;;;;;N;;;;;
+1F6F7;SLED;So;0;ON;;;;;N;;;;;
+1F6F8;FLYING SAUCER;So;0;ON;;;;;N;;;;;
 1F700;ALCHEMICAL SYMBOL FOR QUINTESSENCE;So;0;ON;;;;;N;;;;;
 1F701;ALCHEMICAL SYMBOL FOR AIR;So;0;ON;;;;;N;;;;;
 1F702;ALCHEMICAL SYMBOL FOR FIRE;So;0;ON;;;;;N;;;;;
@@ -29617,6 +30575,18 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 1F8AB;RIGHTWARDS FRONT-TILTED SHADOWED WHITE ARROW;So;0;ON;;;;;N;;;;;
 1F8AC;WHITE ARROW SHAFT WIDTH ONE;So;0;ON;;;;;N;;;;;
 1F8AD;WHITE ARROW SHAFT WIDTH TWO THIRDS;So;0;ON;;;;;N;;;;;
+1F900;CIRCLED CROSS FORMEE WITH FOUR DOTS;So;0;ON;;;;;N;;;;;
+1F901;CIRCLED CROSS FORMEE WITH TWO DOTS;So;0;ON;;;;;N;;;;;
+1F902;CIRCLED CROSS FORMEE;So;0;ON;;;;;N;;;;;
+1F903;LEFT HALF CIRCLE WITH FOUR DOTS;So;0;ON;;;;;N;;;;;
+1F904;LEFT HALF CIRCLE WITH THREE DOTS;So;0;ON;;;;;N;;;;;
+1F905;LEFT HALF CIRCLE WITH TWO DOTS;So;0;ON;;;;;N;;;;;
+1F906;LEFT HALF CIRCLE WITH DOT;So;0;ON;;;;;N;;;;;
+1F907;LEFT HALF CIRCLE;So;0;ON;;;;;N;;;;;
+1F908;DOWNWARD FACING HOOK;So;0;ON;;;;;N;;;;;
+1F909;DOWNWARD FACING NOTCHED HOOK;So;0;ON;;;;;N;;;;;
+1F90A;DOWNWARD FACING HOOK WITH DOT;So;0;ON;;;;;N;;;;;
+1F90B;DOWNWARD FACING NOTCHED HOOK WITH DOT;So;0;ON;;;;;N;;;;;
 1F910;ZIPPER-MOUTH FACE;So;0;ON;;;;;N;;;;;
 1F911;MONEY-MOUTH FACE;So;0;ON;;;;;N;;;;;
 1F912;FACE WITH THERMOMETER;So;0;ON;;;;;N;;;;;
@@ -29632,6 +30602,7 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 1F91C;RIGHT-FACING FIST;So;0;ON;;;;;N;;;;;
 1F91D;HANDSHAKE;So;0;ON;;;;;N;;;;;
 1F91E;HAND WITH INDEX AND MIDDLE FINGERS CROSSED;So;0;ON;;;;;N;;;;;
+1F91F;I LOVE YOU HAND SIGN;So;0;ON;;;;;N;;;;;
 1F920;FACE WITH COWBOY HAT;So;0;ON;;;;;N;;;;;
 1F921;CLOWN FACE;So;0;ON;;;;;N;;;;;
 1F922;NAUSEATED FACE;So;0;ON;;;;;N;;;;;
@@ -29640,7 +30611,17 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 1F925;LYING FACE;So;0;ON;;;;;N;;;;;
 1F926;FACE PALM;So;0;ON;;;;;N;;;;;
 1F927;SNEEZING FACE;So;0;ON;;;;;N;;;;;
+1F928;FACE WITH ONE EYEBROW RAISED;So;0;ON;;;;;N;;;;;
+1F929;GRINNING FACE WITH STAR EYES;So;0;ON;;;;;N;;;;;
+1F92A;GRINNING FACE WITH ONE LARGE AND ONE SMALL EYE;So;0;ON;;;;;N;;;;;
+1F92B;FACE WITH FINGER COVERING CLOSED LIPS;So;0;ON;;;;;N;;;;;
+1F92C;SERIOUS FACE WITH SYMBOLS COVERING MOUTH;So;0;ON;;;;;N;;;;;
+1F92D;SMILING FACE WITH SMILING EYES AND HAND COVERING MOUTH;So;0;ON;;;;;N;;;;;
+1F92E;FACE WITH OPEN MOUTH VOMITING;So;0;ON;;;;;N;;;;;
+1F92F;SHOCKED FACE WITH EXPLODING HEAD;So;0;ON;;;;;N;;;;;
 1F930;PREGNANT WOMAN;So;0;ON;;;;;N;;;;;
+1F931;BREAST-FEEDING;So;0;ON;;;;;N;;;;;
+1F932;PALMS UP TOGETHER;So;0;ON;;;;;N;;;;;
 1F933;SELFIE;So;0;ON;;;;;N;;;;;
 1F934;PRINCE;So;0;ON;;;;;N;;;;;
 1F935;MAN IN TUXEDO;So;0;ON;;;;;N;;;;;
@@ -29665,6 +30646,7 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 1F949;THIRD PLACE MEDAL;So;0;ON;;;;;N;;;;;
 1F94A;BOXING GLOVE;So;0;ON;;;;;N;;;;;
 1F94B;MARTIAL ARTS UNIFORM;So;0;ON;;;;;N;;;;;
+1F94C;CURLING STONE;So;0;ON;;;;;N;;;;;
 1F950;CROISSANT;So;0;ON;;;;;N;;;;;
 1F951;AVOCADO;So;0;ON;;;;;N;;;;;
 1F952;CUCUMBER;So;0;ON;;;;;N;;;;;
@@ -29680,6 +30662,19 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 1F95C;PEANUTS;So;0;ON;;;;;N;;;;;
 1F95D;KIWIFRUIT;So;0;ON;;;;;N;;;;;
 1F95E;PANCAKES;So;0;ON;;;;;N;;;;;
+1F95F;DUMPLING;So;0;ON;;;;;N;;;;;
+1F960;FORTUNE COOKIE;So;0;ON;;;;;N;;;;;
+1F961;TAKEOUT BOX;So;0;ON;;;;;N;;;;;
+1F962;CHOPSTICKS;So;0;ON;;;;;N;;;;;
+1F963;BOWL WITH SPOON;So;0;ON;;;;;N;;;;;
+1F964;CUP WITH STRAW;So;0;ON;;;;;N;;;;;
+1F965;COCONUT;So;0;ON;;;;;N;;;;;
+1F966;BROCCOLI;So;0;ON;;;;;N;;;;;
+1F967;PIE;So;0;ON;;;;;N;;;;;
+1F968;PRETZEL;So;0;ON;;;;;N;;;;;
+1F969;CUT OF MEAT;So;0;ON;;;;;N;;;;;
+1F96A;SANDWICH;So;0;ON;;;;;N;;;;;
+1F96B;CANNED FOOD;So;0;ON;;;;;N;;;;;
 1F980;CRAB;So;0;ON;;;;;N;;;;;
 1F981;LION FACE;So;0;ON;;;;;N;;;;;
 1F982;SCORPION;So;0;ON;;;;;N;;;;;
@@ -29698,7 +30693,36 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 1F98F;RHINOCEROS;So;0;ON;;;;;N;;;;;
 1F990;SHRIMP;So;0;ON;;;;;N;;;;;
 1F991;SQUID;So;0;ON;;;;;N;;;;;
+1F992;GIRAFFE FACE;So;0;ON;;;;;N;;;;;
+1F993;ZEBRA FACE;So;0;ON;;;;;N;;;;;
+1F994;HEDGEHOG;So;0;ON;;;;;N;;;;;
+1F995;SAUROPOD;So;0;ON;;;;;N;;;;;
+1F996;T-REX;So;0;ON;;;;;N;;;;;
+1F997;CRICKET;So;0;ON;;;;;N;;;;;
 1F9C0;CHEESE WEDGE;So;0;ON;;;;;N;;;;;
+1F9D0;FACE WITH MONOCLE;So;0;ON;;;;;N;;;;;
+1F9D1;ADULT;So;0;ON;;;;;N;;;;;
+1F9D2;CHILD;So;0;ON;;;;;N;;;;;
+1F9D3;OLDER ADULT;So;0;ON;;;;;N;;;;;
+1F9D4;BEARDED PERSON;So;0;ON;;;;;N;;;;;
+1F9D5;PERSON WITH HEADSCARF;So;0;ON;;;;;N;;;;;
+1F9D6;PERSON IN STEAMY ROOM;So;0;ON;;;;;N;;;;;
+1F9D7;PERSON CLIMBING;So;0;ON;;;;;N;;;;;
+1F9D8;PERSON IN LOTUS POSITION;So;0;ON;;;;;N;;;;;
+1F9D9;MAGE;So;0;ON;;;;;N;;;;;
+1F9DA;FAIRY;So;0;ON;;;;;N;;;;;
+1F9DB;VAMPIRE;So;0;ON;;;;;N;;;;;
+1F9DC;MERPERSON;So;0;ON;;;;;N;;;;;
+1F9DD;ELF;So;0;ON;;;;;N;;;;;
+1F9DE;GENIE;So;0;ON;;;;;N;;;;;
+1F9DF;ZOMBIE;So;0;ON;;;;;N;;;;;
+1F9E0;BRAIN;So;0;ON;;;;;N;;;;;
+1F9E1;ORANGE HEART;So;0;ON;;;;;N;;;;;
+1F9E2;BILLED CAP;So;0;ON;;;;;N;;;;;
+1F9E3;SCARF;So;0;ON;;;;;N;;;;;
+1F9E4;GLOVES;So;0;ON;;;;;N;;;;;
+1F9E5;COAT;So;0;ON;;;;;N;;;;;
+1F9E6;SOCKS;So;0;ON;;;;;N;;;;;
 20000;<CJK Ideograph Extension B, First>;Lo;0;L;;;;;N;;;;;
 2A6D6;<CJK Ideograph Extension B, Last>;Lo;0;L;;;;;N;;;;;
 2A700;<CJK Ideograph Extension C, First>;Lo;0;L;;;;;N;;;;;
@@ -29707,6 +30731,8 @@ FFFD;REPLACEMENT CHARACTER;So;0;ON;;;;;N;;;;;
 2B81D;<CJK Ideograph Extension D, Last>;Lo;0;L;;;;;N;;;;;
 2B820;<CJK Ideograph Extension E, First>;Lo;0;L;;;;;N;;;;;
 2CEA1;<CJK Ideograph Extension E, Last>;Lo;0;L;;;;;N;;;;;
+2CEB0;<CJK Ideograph Extension F, First>;Lo;0;L;;;;;N;;;;;
+2EBE0;<CJK Ideograph Extension F, Last>;Lo;0;L;;;;;N;;;;;
 2F800;CJK COMPATIBILITY IDEOGRAPH-2F800;Lo;0;L;4E3D;;;;N;;;;;
 2F801;CJK COMPATIBILITY IDEOGRAPH-2F801;Lo;0;L;4E38;;;;N;;;;;
 2F802;CJK COMPATIBILITY IDEOGRAPH-2F802;Lo;0;L;4E41;;;;N;;;;;
diff --git a/lib/stdlib/uc_spec/gen_unicode_mod.escript b/lib/stdlib/uc_spec/gen_unicode_mod.escript
index 73c351e1af..fe5a860d45 100755
--- a/lib/stdlib/uc_spec/gen_unicode_mod.escript
+++ b/lib/stdlib/uc_spec/gen_unicode_mod.escript
@@ -65,7 +65,7 @@ main(_) ->
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 parse_unicode_data(Line0, Acc) ->
-    Line = string:strip(Line0, right, $\n),
+    Line = string:chomp(Line0),
     [CodePoint,Name,_Cat,Class,_BiDi,Decomp,
      _N1,_N2,_N3,_BDMirror,_Uni1,_Iso|Case] = tokens(Line, ";"),
     {Dec,Comp} = case to_decomp(Decomp) of
@@ -78,14 +78,14 @@ parse_unicode_data(Line0, Acc) ->
      |Acc].
 
 to_class(String) ->
-    list_to_integer(string:strip(String, both)).
+    list_to_integer(string:trim(String, both)).
 
 to_decomp("") -> [];
 to_decomp("<" ++ Str) ->
-    [Tag,Rest]  = string:tokens(Str, ">"),
+    [Tag,Rest]  = string:lexemes(Str, ">"),
     {list_to_atom(Tag), to_decomp(Rest)};
 to_decomp(CodePoints) ->
-    CPL = string:tokens(CodePoints, " "),
+    CPL = string:lexemes(CodePoints, " "),
     [hex_to_int(CP) || CP <- CPL].
 
 to_case(["","",""]) -> [];
@@ -105,20 +105,20 @@ parse_special_casing(Line, Table) ->
     array:set(CP, Entry#cp{cs=Case}, Table).
 
 to_scase([Lower,Title,Upper|_]) ->
-    {unlist([hex_to_int(CP) || CP <- string:strip(string:tokens(Upper, " "), both)]),
-     unlist([hex_to_int(CP) || CP <- string:strip(string:tokens(Lower, " "), both)]),
-     unlist([hex_to_int(CP) || CP <- string:strip(string:tokens(Title, " "), both)]),
+    {unlist([hex_to_int(CP) || CP <- string:lexemes(Upper, " ")]),
+     unlist([hex_to_int(CP) || CP <- string:lexemes(Lower, " ")]),
+     unlist([hex_to_int(CP) || CP <- string:lexemes(Title, " ")]),
      []}.
 
 parse_case_folding(Line, Table) ->
     [CodePoint, Class0, CaseStr |_Comments] = tokens(Line, ";"),
-    Class = string:strip(Class0, both),
+    Class = string:trim(Class0, both),
     if Class =:= "T" -> Table; %% Do not support localization yet
        Class =:= "S" -> Table; %% Ignore simple
        true ->
             CP = hex_to_int(CodePoint),
             Case = unlist([hex_to_int(CPC) ||
-                              CPC <- string:strip(string:tokens(CaseStr, " "), both)]),
+                              CPC <- string:lexemes(CaseStr, " ")]),
             #cp{cs={U,L,T,_}} = Entry = array:get(CP, Table),
             array:set(CP, Entry#cp{cs={U,L,T,Case}}, Table)
     end.
@@ -186,7 +186,7 @@ gen_static(Fd) ->
                  "        {U,L} -> #{upper=>U,lower=>L,title=>U,fold=>L};\n"
                  "        {U,L,T,F} -> #{upper=>U,lower=>L,title=>T,fold=>F}\n"
                  "    end.\n\n"),
-    io:put_chars(Fd, "spec_version() -> {9,0}.\n\n\n"),
+    io:put_chars(Fd, "spec_version() -> {10,0}.\n\n\n"),
     io:put_chars(Fd, "class(Codepoint) -> {CCC,_,_} = unicode_table(Codepoint),\n    CCC.\n\n"),
     io:put_chars(Fd, "-spec uppercase(unicode:chardata()) -> "
                  "maybe_improper_list(gc(),unicode:chardata()).\n"),
@@ -886,10 +886,10 @@ optimize_ranges_1(Rs) ->
 
 hex_to_int([]) -> [];
 hex_to_int(HexStr) ->
-    list_to_integer(string:strip(HexStr, both), 16).
+    list_to_integer(string:trim(HexStr, both), 16).
 
 to_atom(Str) ->
-    list_to_atom(string:to_lower(string:strip(Str, both))).
+    list_to_atom(string:lowercase(string:trim(Str, both))).
 
 foldl(Fun, Acc, Fd) ->
     Get = fun() -> file:read_line(Fd) end,
@@ -909,7 +909,7 @@ foldl_1(Fun, Acc, Get) ->
 
 
 
-%% Differs from string:tokens, it returns empty string as token between two delimiters
+%% Differs from string:lexemes, it returns empty string as token between two delimiters
 tokens(S, [C]) ->
     tokens(lists:reverse(S), C, []).
 
diff --git a/lib/syntax_tools/src/Makefile b/lib/syntax_tools/src/Makefile
index 8325db45a8..c21d2f49c8 100644
--- a/lib/syntax_tools/src/Makefile
+++ b/lib/syntax_tools/src/Makefile
@@ -75,7 +75,7 @@ $(EBIN)/%.$(EMULATOR):%.erl
 
 # special rules and dependencies to apply the transform to itself
 $(EBIN)/merl_transform.beam: $(EBIN)/merl.beam ./merl_transform.beam \
-			../include/merl.hrl \
+			../include/merl.hrl $(EBIN)/erl_comment_scan.beam \
 			$(EBIN)/erl_syntax.beam $(EBIN)/erl_syntax_lib.beam
 ./merl_transform.beam: ./merl_transform.erl $(EBIN)/merl.beam \
 			../include/merl.hrl
diff --git a/lib/syntax_tools/src/erl_comment_scan.erl b/lib/syntax_tools/src/erl_comment_scan.erl
index 07e501e553..e3eb95b819 100644
--- a/lib/syntax_tools/src/erl_comment_scan.erl
+++ b/lib/syntax_tools/src/erl_comment_scan.erl
@@ -208,7 +208,7 @@ scan_comment([], Cs1, L, Col, M, Ack) ->
 seen_comment(Cs, Cs1, L, Col, M, Ack) ->
     %% Compute indentation and strip trailing spaces
     N = Col - M,
-    Text = lists:reverse(string:strip(Cs1, left)),
+    Text = lists:reverse(string:trim(Cs1, leading)),
     Ack1 = [{L, Col + 1, N, Text} | Ack],
     scan_lines(Cs, L + 1, 0, 0, Ack1).
 
diff --git a/lib/syntax_tools/src/erl_prettypr.erl b/lib/syntax_tools/src/erl_prettypr.erl
index 40ddd2b22a..f03f326278 100644
--- a/lib/syntax_tools/src/erl_prettypr.erl
+++ b/lib/syntax_tools/src/erl_prettypr.erl
@@ -774,9 +774,17 @@ lay_2(Node, Ctxt) ->
 	class_qualifier ->
 	    Ctxt1 = set_prec(Ctxt, max_prec()),
 	    D1 = lay(erl_syntax:class_qualifier_argument(Node), Ctxt1),
-	    D2 = lay(erl_syntax:class_qualifier_body(Node), Ctxt1),
-	    beside(D1, beside(text(":"), D2));
-
+            D2 = lay(erl_syntax:class_qualifier_body(Node), Ctxt1),
+            Stacktrace = erl_syntax:class_qualifier_stacktrace(Node),
+            case erl_syntax:variable_name(Stacktrace) of
+                '_' ->
+                    beside(D1, beside(text(":"), D2));
+                _ ->
+                    D3 = lay(erl_syntax:class_qualifier_stacktrace(Node),
+                             Ctxt1),
+                    beside(D1, beside(beside(text(":"), D2),
+                                      beside(text(":"), D3)))
+            end;
 	comment ->
 	    D = stack_comment_lines(
 		  erl_syntax:comment_text(Node)),
diff --git a/lib/syntax_tools/src/erl_syntax.erl b/lib/syntax_tools/src/erl_syntax.erl
index 9b2b503762..ed552b73df 100644
--- a/lib/syntax_tools/src/erl_syntax.erl
+++ b/lib/syntax_tools/src/erl_syntax.erl
@@ -342,8 +342,10 @@
 	 typed_record_field_body/1,
          typed_record_field_type/1,
 	 class_qualifier/2,
+	 class_qualifier/3,
 	 class_qualifier_argument/1,
 	 class_qualifier_body/1,
+	 class_qualifier_stacktrace/1,
 	 tuple/1,
 	 tuple_elements/1,
 	 tuple_size/1,
@@ -3884,7 +3886,7 @@ fold_try_clause({clause, Pos, [P], Guard, Body}) ->
 	     class_qualifier ->
 		 {tuple, Pos, [class_qualifier_argument(P),
 			       class_qualifier_body(P),
-			       {var, Pos, '_'}]};
+			       class_qualifier_stacktrace(P)]};
 	     _ ->
 		 {tuple, Pos, [{atom, Pos, throw}, P, {var, Pos, '_'}]}
 	 end,
@@ -3896,9 +3898,9 @@ unfold_try_clauses(Cs) ->
 unfold_try_clause({clause, Pos, [{tuple, _, [{atom, _, throw}, V, _]}],
 		   Guard, Body}) ->
     {clause, Pos, [V], Guard, Body};
-unfold_try_clause({clause, Pos, [{tuple, _, [C, V, _]}],
+unfold_try_clause({clause, Pos, [{tuple, _, [C, V, Stacktrace]}],
 		   Guard, Body}) ->
-    {clause, Pos, [class_qualifier(C, V)], Guard, Body}.
+    {clause, Pos, [class_qualifier(C, V, Stacktrace)], Guard, Body}.
 
 
 %% =====================================================================
@@ -6725,9 +6727,12 @@ try_expr_after(Node) ->
 %%
 %% @see class_qualifier_argument/1
 %% @see class_qualifier_body/1
+%% @see class_qualifier_stacktrace/1
 %% @see try_expr/4
 
--record(class_qualifier, {class :: syntaxTree(), body :: syntaxTree()}).
+-record(class_qualifier, {class :: syntaxTree(),
+                          body :: syntaxTree(),
+                          stacktrace :: syntaxTree()}).
 
 %% type(Node) = class_qualifier
 %% data(Node) = #class_qualifier{class :: Class, body :: Body}
@@ -6737,8 +6742,27 @@ try_expr_after(Node) ->
 -spec class_qualifier(syntaxTree(), syntaxTree()) -> syntaxTree().
 
 class_qualifier(Class, Body) ->
+    Underscore = {var, get_pos(Body), '_'},
     tree(class_qualifier,
-	 #class_qualifier{class = Class, body = Body}).
+	 #class_qualifier{class = Class, body = Body,
+                          stacktrace = Underscore}).
+
+%% =====================================================================
+%% @doc Creates an abstract class qualifier. The result represents
+%% "<code><em>Class</em>:<em>Body</em>:<em>Stacktrace</em></code>".
+%%
+%% @see class_qualifier_argument/1
+%% @see class_qualifier_body/1
+%% @see try_expr/4
+
+-spec class_qualifier(syntaxTree(), syntaxTree(), syntaxTree()) ->
+                             syntaxTree().
+
+class_qualifier(Class, Body, Stacktrace) ->
+    tree(class_qualifier,
+	 #class_qualifier{class = Class,
+                          body = Body,
+                          stacktrace = Stacktrace}).
 
 
 %% =====================================================================
@@ -6763,6 +6787,16 @@ class_qualifier_argument(Node) ->
 class_qualifier_body(Node) ->
     (data(Node))#class_qualifier.body.
 
+%% =====================================================================
+%% @doc Returns the stacktrace subtree of a `class_qualifier' node.
+%%
+%% @see class_qualifier/2
+
+-spec class_qualifier_stacktrace(syntaxTree()) -> syntaxTree().
+
+class_qualifier_stacktrace(Node) ->
+    (data(Node))#class_qualifier.stacktrace.
+
 
 %% =====================================================================
 %% @doc Creates an abstract "implicit fun" expression. If
diff --git a/lib/syntax_tools/src/merl_transform.erl b/lib/syntax_tools/src/merl_transform.erl
index b298bc407f..571d7e4d86 100644
--- a/lib/syntax_tools/src/merl_transform.erl
+++ b/lib/syntax_tools/src/merl_transform.erl
@@ -196,7 +196,7 @@ var_name(V) -> V.
 
 var_to_tag(V) when is_integer(V) -> V;
 var_to_tag(V) ->
-    list_to_atom(string:to_lower(atom_to_list(V))).
+    list_to_atom(string:lowercase(atom_to_list(V))).
 
 pre_expand_case(Expr, Clauses, Line) ->
     merl:qquote(Line, "merl:switch(_@expr, _@clauses)",
diff --git a/lib/tools/emacs/erlang.el b/lib/tools/emacs/erlang.el
index 411e0e13df..6b93d63182 100644
--- a/lib/tools/emacs/erlang.el
+++ b/lib/tools/emacs/erlang.el
@@ -885,7 +885,6 @@ resulting regexp is surrounded by \\_< and \\_>."
       "append"
       "append_element"
       "await_proc_exit"
-      "await_sched_wall_time_modifications"
       "bump_reductions"
       "call_on_load_function"
       "cancel_timer"
@@ -895,16 +894,16 @@ resulting regexp is surrounded by \\_< and \\_>."
       "decode_packet"
       "delay_trap"
       "delete_element"
-      "dexit"
-      "dgroup_leader"
       "display"
       "display_nl"
       "display_string"
-      "dist_exit"
-      "dlink"
+      "dist_get_stat"
+      "dist_ctrl_get_data"
+      "dist_ctrl_get_data_notification"
+      "dist_ctrl_input_handler"
+      "dist_ctrl_put_data"
       "dmonitor_node"
       "dmonitor_p"
-      "dsend"
       "dt_append_vm_tag_data"
       "dt_get_tag"
       "dt_get_tag_data"
@@ -912,7 +911,6 @@ resulting regexp is surrounded by \\_< and \\_>."
       "dt_put_tag"
       "dt_restore_tag"
       "dt_spread_tag"
-      "dunlink"
       "convert_time_unit"
       "external_size"
       "finish_after_on_load"
@@ -924,7 +922,6 @@ resulting regexp is surrounded by \\_< and \\_>."
       "function_exported"
       "garbage_collect_message_area"
       "gather_gc_info_result"
-      "gather_sched_wall_time_result"
       "get_cookie"
       "get_module_info"
       "get_stacktrace"
diff --git a/lib/tools/src/cover.erl b/lib/tools/src/cover.erl
index 5517882ffa..801bbc7461 100644
--- a/lib/tools/src/cover.erl
+++ b/lib/tools/src/cover.erl
@@ -2439,11 +2439,11 @@ do_analyse_to_file1(Module, OutFile, ErlFile, HTML) ->
                    Timestamp =
                        io_lib:format("~p-~s-~s at ~s:~s:~s",
                                      [Y,
-                                      string:right(integer_to_list(Mo), 2, $0),
-                                      string:right(integer_to_list(D),  2, $0),
-                                      string:right(integer_to_list(H),  2, $0),
-                                      string:right(integer_to_list(Mi), 2, $0),
-                                      string:right(integer_to_list(S),  2, $0)]),
+                                      string:pad(integer_to_list(Mo), 2, leading, $0),
+                                      string:pad(integer_to_list(D),  2, leading, $0),
+                                      string:pad(integer_to_list(H),  2, leading, $0),
+                                      string:pad(integer_to_list(Mi), 2, leading, $0),
+                                      string:pad(integer_to_list(S),  2, leading, $0)]),
 
                     H2Bin = unicode:characters_to_binary(
                               ["File generated from ",ErlFile," by COVER ",
@@ -2493,12 +2493,12 @@ print_lines(Module, CovLines, InFd, OutFd, L, HTML) ->
                     if N=:=0, HTML=:=true ->
                            LineNoNL = Line -- "\n",
                            Str = "     0",
-                           %%Str = string:right("0", 6, 32),
+                           %%Str = string:pad("0", 6, leading, $\s),
                            RedLine = ["<font color=red>",Str,fill1(),
                                       LineNoNL,"</font>\n"],
                            ok = file:write(OutFd, RedLine);
                        N < 1000000 ->
-                           Str = string:right(integer_to_list(N), 6, 32),
+                           Str = string:pad(integer_to_list(N), 6, leading, $\s),
                            ok = file:write(OutFd, [Str,fill1(),Line]);
                        N < 10000000 ->
                            Str = integer_to_list(N),
diff --git a/lib/tools/src/xref_utils.erl b/lib/tools/src/xref_utils.erl
index 02e207d40c..eca751337b 100644
--- a/lib/tools/src/xref_utils.erl
+++ b/lib/tools/src/xref_utils.erl
@@ -557,12 +557,9 @@ subdir(Dir, SubDir, true) ->
 
 %% Avoid "App-01.01" - the zeroes will be lost.
 filename2appl(File) ->
-    Pos = string:rstr(File, "-"),
-    true = Pos > 1,
-    V = string:sub_string(File, Pos+1),
-    true = string:len(V) > 0,
-    VsnT = string:tokens(V, "."),
-    ApplName = string:sub_string(File, 1, Pos-1),
+    [ApplName, V] = string:split(File, "-", trailing),
+    true = string:length(V) > 0,
+    VsnT = string:lexemes(V, "."),
     Vsn = [list_to_integer(Vsn) || Vsn <- VsnT],
     {list_to_atom(ApplName),Vsn}.
 
diff --git a/lib/tools/test/fprof_SUITE.erl b/lib/tools/test/fprof_SUITE.erl
index 8fd164a4b3..ae0e7253ad 100644
--- a/lib/tools/test/fprof_SUITE.erl
+++ b/lib/tools/test/fprof_SUITE.erl
@@ -51,7 +51,7 @@
 
 suite() ->
     [{ct_hooks,[ts_install_cth]},
-     {timetrap,{seconds,60}}].
+     {timetrap,{seconds,240}}].
 
 all() -> 
     case test_server:is_native(fprof_SUITE) of
@@ -571,7 +571,7 @@ seq_r(Start, Stop, Succ, R) ->
 
 create_file_slow(Name, N) when is_integer(N), N >= 0 ->
     {ok, FD} = 
-    file:open(Name, [raw, write, delayed_write, binary]),
+    file:open(Name, [raw, write, binary]),
     if N > 256 ->
            ok = file:write(FD,
                            lists:map(fun (X) -> <<X:32/unsigned>> end,
diff --git a/lib/tools/test/xref_SUITE.erl b/lib/tools/test/xref_SUITE.erl
index d651cbcfee..018f632948 100644
--- a/lib/tools/test/xref_SUITE.erl
+++ b/lib/tools/test/xref_SUITE.erl
@@ -1112,27 +1112,16 @@ read_expected(Version) ->
           {POS7+2,{FF,{erlang,spawn_opt,4}}},
           {POS8+1,{FF,{hej,san,1}}},
           {POS8+4,{FF,{a,b,1}}},
-          {POS8+4,{FF,{erlang,apply,2}}},
-          {POS8+5,{FF,{erlang,apply,2}}},
           {POS8+6,{FF,{m,f,1}}},
           {POS9+1,{FF,{read,bi,0}}},
           {POS9+2,{FF,{a,b,1}}},
-          {POS9+2,{FF,{erlang,apply,2}}},
-          {POS9+3,{FF,{erlang,apply,2}}},
-          {POS9+4,{FF,{erlang,apply,2}}},
           {POS9+4,{FF,{erlang,not_a_function,1}}},
           {POS9+5,{FF,{mod,func,2}}},
           {POS9+6,{FF,{erlang,apply,1}}},
-          {POS9+7,{FF,{erlang,apply,2}}},
           {POS9+7,{FF,{math,add3,1}}},
           {POS9+8,{FF,{q,f,1}}},
-          {POS10+4,{FF,{erlang,apply,2}}},
           {POS10+5,{FF,{mod1,fun1,1}}},
-          {POS11+6,{FF,{erlang,apply,2}}},
-          {POS12+1,{FF,{erlang,apply,2}}},
-          {POS12+4,{FF,{erlang,apply,2}}},
           {POS12+5,{FF,{m3,f3,2}}},
-          {POS12+7,{FF,{erlang,apply,2}}},
           {POS13+1,{FF,{dm,df,1}}},
           {POS13+6,{{read,bi,0},{foo,module_info,0}}},
           {POS13+7,{{read,bi,0},{read,module_info,0}}},
@@ -1162,15 +1151,26 @@ read_expected(Version) ->
             {POS3+3,  {FF,{erlang,spawn_link,3}}},
             {POS3+4, {FF,{erlang,spawn_link,3}}},
             {POS6+4, {FF,{erlang,spawn,3}}},
+            {POS8+4,{FF,{erlang,apply,2}}},
+            {POS8+5,{FF,{erlang,apply,2}}},
             {POS8+6,{FF,{erlang,apply,3}}},
             {POS8+7,{FF,{erlang,apply,3}}},
             {POS9+1,{FF,{erlang,apply,3}}},
+            {POS9+2,{FF,{erlang,apply,2}}},
+            {POS9+3,{FF,{erlang,apply,2}}},
+            {POS9+4,{FF,{erlang,apply,2}}},
             {POS9+5,{FF,{erlang,apply,3}}},
+            {POS9+7,{FF,{erlang,apply,2}}},
+            {POS10+4,{FF,{erlang,apply,2}}},
             {POS11+1,{FF,{erlang,apply,3}}},
             {POS11+2,{FF,{erlang,apply,3}}},
             {POS11+3,{FF,{erlang,apply,3}}},
             {POS11+4,{FF,{erlang,apply,3}}},
+            {POS11+6,{FF,{erlang,apply,2}}},
+            {POS12+1,{FF,{erlang,apply,2}}},
+            {POS12+4,{FF,{erlang,apply,2}}},
             {POS12+5,{FF,{erlang,apply,3}}},
+            {POS12+7,{FF,{erlang,apply,2}}},
             {POS12+8,{FF,{erlang,apply,3}}},
             {POS13+5, {{read,bi,0},{erlang,length,1}}},
             {POS14+3, {{read,bi,0},{erlang,length,1}}}],
diff --git a/lib/wx/examples/demo/demo.erl b/lib/wx/examples/demo/demo.erl
index 8fb70ad7b0..8f3291305b 100644
--- a/lib/wx/examples/demo/demo.erl
+++ b/lib/wx/examples/demo/demo.erl
@@ -411,7 +411,7 @@ find(Ed) ->
 
 keyWords() ->
     L = ["after","begin","case","try","cond","catch","andalso","orelse",
-	 "end","fun","if","let","of","query","receive","when","bnot","not",
+	 "end","fun","if","let","of","receive","when","bnot","not",
 	 "div","rem","band","and","bor","bxor","bsl","bsr","or","xor"],
     lists:flatten([K ++ " " || K <- L] ++ [0]).
 
diff --git a/make/otp.mk.in b/make/otp.mk.in
index b06c51d0fb..1d538fa528 100644
--- a/make/otp.mk.in
+++ b/make/otp.mk.in
@@ -47,9 +47,9 @@ CROSS_COMPILING = @CROSS_COMPILING@
 # ----------------------------------------------------
 DEFAULT_TARGETS =  opt debug release release_docs clean docs
 
-DEFAULT_FLAVOR=@DEFAULT_FLAVOR@
-FLAVORS=@FLAVORS@
-TYPES=@TYPES@
+TYPES = @TYPES@
+
+USE_PGO = @USE_PGO@
 
 # Slash separated list of return values from $(origin VAR)
 # that are untrusted - set default in this file instead.
@@ -62,8 +62,8 @@ DUBIOUS_ORIGINS = /undefined/environment/
 #	HiPE
 # ----------------------------------------------------
 
-HIPE_ENABLED=@HIPE_ENABLED@
-NATIVE_LIBS_ENABLED=@NATIVE_LIBS_ENABLED@
+HIPE_ENABLED = @HIPE_ENABLED@
+NATIVE_LIBS_ENABLED = @NATIVE_LIBS_ENABLED@
 
 # ----------------------------------------------------
 #	Command macros
@@ -85,6 +85,7 @@ LD = @LD@
 RANLIB = @RANLIB@
 AR = @AR@
 PERL = @PERL@
+LLVM_PROFDATA = @LLVM_PROFDATA@
 
 BITS64 = @BITS64@
 
diff --git a/make/output.mk.in b/make/output.mk.in
index 171d2456aa..7c6533fddd 100644
--- a/make/output.mk.in
+++ b/make/output.mk.in
@@ -139,3 +139,7 @@ vsn_verbose = $(vsn_verbose_$(V))
 
 yecc_verbose_0 = @echo " YECC	"$@;
 yecc_verbose = $(yecc_verbose_$(V))
+
+llvm_profdata_verbose_0 = @echo " LLVM_PROFDATA	"$@;
+llvm_profdata_verbose = $(llvm_profdata_verbose_$(V))
+V_LLVM_PROFDATA = $(llvm_profdata_verbose)$(LLVM_PROFDATA)
diff --git a/otp_versions.table b/otp_versions.table
index fa2c600491..2e1052264d 100644
--- a/otp_versions.table
+++ b/otp_versions.table
@@ -1,6 +1,7 @@
 OTP-20.2.2 : mnesia-4.15.3 # asn1-5.0.4 common_test-1.15.3 compiler-7.1.4 cosEvent-2.2.2 cosEventDomain-1.2.2 cosFileTransfer-1.2.2 cosNotification-1.2.3 cosProperty-1.2.3 cosTime-1.2.3 cosTransactions-1.3.3 crypto-4.2 debugger-4.2.4 dialyzer-3.2.3 diameter-2.1.3 edoc-0.9.2 eldap-1.2.3 erl_docgen-0.7.2 erl_interface-3.10.1 erts-9.2 et-1.6.1 eunit-2.3.5 hipe-3.17 ic-4.4.3 inets-6.4.5 jinterface-1.8.1 kernel-5.4.1 megaco-3.18.3 observer-2.6 odbc-2.12.1 orber-3.8.4 os_mon-2.4.4 otp_mibs-1.1.2 parsetools-2.1.6 public_key-1.5.2 reltool-0.7.5 runtime_tools-1.12.3 sasl-3.1.1 snmp-5.2.9 ssh-4.6.4 ssl-8.2.3 stdlib-3.4.3 syntax_tools-2.1.4 tools-2.11.1 wx-1.8.3 xmerl-1.3.16 :
 OTP-20.2.1 : ssh-4.6.4 # asn1-5.0.4 common_test-1.15.3 compiler-7.1.4 cosEvent-2.2.2 cosEventDomain-1.2.2 cosFileTransfer-1.2.2 cosNotification-1.2.3 cosProperty-1.2.3 cosTime-1.2.3 cosTransactions-1.3.3 crypto-4.2 debugger-4.2.4 dialyzer-3.2.3 diameter-2.1.3 edoc-0.9.2 eldap-1.2.3 erl_docgen-0.7.2 erl_interface-3.10.1 erts-9.2 et-1.6.1 eunit-2.3.5 hipe-3.17 ic-4.4.3 inets-6.4.5 jinterface-1.8.1 kernel-5.4.1 megaco-3.18.3 mnesia-4.15.2 observer-2.6 odbc-2.12.1 orber-3.8.4 os_mon-2.4.4 otp_mibs-1.1.2 parsetools-2.1.6 public_key-1.5.2 reltool-0.7.5 runtime_tools-1.12.3 sasl-3.1.1 snmp-5.2.9 ssl-8.2.3 stdlib-3.4.3 syntax_tools-2.1.4 tools-2.11.1 wx-1.8.3 xmerl-1.3.16 :
 OTP-20.2 : asn1-5.0.4 common_test-1.15.3 compiler-7.1.4 cosEvent-2.2.2 cosEventDomain-1.2.2 cosFileTransfer-1.2.2 cosNotification-1.2.3 cosProperty-1.2.3 cosTime-1.2.3 cosTransactions-1.3.3 crypto-4.2 debugger-4.2.4 dialyzer-3.2.3 diameter-2.1.3 edoc-0.9.2 eldap-1.2.3 erl_docgen-0.7.2 erl_interface-3.10.1 erts-9.2 eunit-2.3.5 hipe-3.17 ic-4.4.3 inets-6.4.5 jinterface-1.8.1 kernel-5.4.1 megaco-3.18.3 mnesia-4.15.2 observer-2.6 odbc-2.12.1 orber-3.8.4 os_mon-2.4.4 otp_mibs-1.1.2 parsetools-2.1.6 public_key-1.5.2 runtime_tools-1.12.3 sasl-3.1.1 snmp-5.2.9 ssh-4.6.3 ssl-8.2.3 stdlib-3.4.3 syntax_tools-2.1.4 tools-2.11.1 wx-1.8.3 xmerl-1.3.16 # et-1.6.1 reltool-0.7.5 :
+OTP-20.1.7.1 : kernel-5.4.0.1 # asn1-5.0.3 common_test-1.15.2 compiler-7.1.3 cosEvent-2.2.1 cosEventDomain-1.2.1 cosFileTransfer-1.2.1 cosNotification-1.2.2 cosProperty-1.2.2 cosTime-1.2.2 cosTransactions-1.3.2 crypto-4.1 debugger-4.2.3 dialyzer-3.2.2 diameter-2.1.2 edoc-0.9.1 eldap-1.2.2 erl_docgen-0.7.1 erl_interface-3.10 erts-9.1.5 et-1.6.1 eunit-2.3.4 hipe-3.16.1 ic-4.4.2 inets-6.4.4 jinterface-1.8 megaco-3.18.2 mnesia-4.15.1 observer-2.5 odbc-2.12 orber-3.8.3 os_mon-2.4.3 otp_mibs-1.1.1 parsetools-2.1.5 public_key-1.5.1 reltool-0.7.5 runtime_tools-1.12.2 sasl-3.1 snmp-5.2.8 ssh-4.6.2 ssl-8.2.2 stdlib-3.4.2 syntax_tools-2.1.3 tools-2.11 wx-1.8.2 xmerl-1.3.15 :
 OTP-20.1.7 : public_key-1.5.1 ssl-8.2.2 # asn1-5.0.3 common_test-1.15.2 compiler-7.1.3 cosEvent-2.2.1 cosEventDomain-1.2.1 cosFileTransfer-1.2.1 cosNotification-1.2.2 cosProperty-1.2.2 cosTime-1.2.2 cosTransactions-1.3.2 crypto-4.1 debugger-4.2.3 dialyzer-3.2.2 diameter-2.1.2 edoc-0.9.1 eldap-1.2.2 erl_docgen-0.7.1 erl_interface-3.10 erts-9.1.5 et-1.6.1 eunit-2.3.4 hipe-3.16.1 ic-4.4.2 inets-6.4.4 jinterface-1.8 kernel-5.4 megaco-3.18.2 mnesia-4.15.1 observer-2.5 odbc-2.12 orber-3.8.3 os_mon-2.4.3 otp_mibs-1.1.1 parsetools-2.1.5 reltool-0.7.5 runtime_tools-1.12.2 sasl-3.1 snmp-5.2.8 ssh-4.6.2 stdlib-3.4.2 syntax_tools-2.1.3 tools-2.11 wx-1.8.2 xmerl-1.3.15 :
 OTP-20.1.6 : erts-9.1.5 ssh-4.6.2 # asn1-5.0.3 common_test-1.15.2 compiler-7.1.3 cosEvent-2.2.1 cosEventDomain-1.2.1 cosFileTransfer-1.2.1 cosNotification-1.2.2 cosProperty-1.2.2 cosTime-1.2.2 cosTransactions-1.3.2 crypto-4.1 debugger-4.2.3 dialyzer-3.2.2 diameter-2.1.2 edoc-0.9.1 eldap-1.2.2 erl_docgen-0.7.1 erl_interface-3.10 et-1.6.1 eunit-2.3.4 hipe-3.16.1 ic-4.4.2 inets-6.4.4 jinterface-1.8 kernel-5.4 megaco-3.18.2 mnesia-4.15.1 observer-2.5 odbc-2.12 orber-3.8.3 os_mon-2.4.3 otp_mibs-1.1.1 parsetools-2.1.5 public_key-1.5 reltool-0.7.5 runtime_tools-1.12.2 sasl-3.1 snmp-5.2.8 ssl-8.2.1 stdlib-3.4.2 syntax_tools-2.1.3 tools-2.11 wx-1.8.2 xmerl-1.3.15 :
 OTP-20.1.5 : erts-9.1.4 inets-6.4.4 # asn1-5.0.3 common_test-1.15.2 compiler-7.1.3 cosEvent-2.2.1 cosEventDomain-1.2.1 cosFileTransfer-1.2.1 cosNotification-1.2.2 cosProperty-1.2.2 cosTime-1.2.2 cosTransactions-1.3.2 crypto-4.1 debugger-4.2.3 dialyzer-3.2.2 diameter-2.1.2 edoc-0.9.1 eldap-1.2.2 erl_docgen-0.7.1 erl_interface-3.10 et-1.6.1 eunit-2.3.4 hipe-3.16.1 ic-4.4.2 jinterface-1.8 kernel-5.4 megaco-3.18.2 mnesia-4.15.1 observer-2.5 odbc-2.12 orber-3.8.3 os_mon-2.4.3 otp_mibs-1.1.1 parsetools-2.1.5 public_key-1.5 reltool-0.7.5 runtime_tools-1.12.2 sasl-3.1 snmp-5.2.8 ssh-4.6.1 ssl-8.2.1 stdlib-3.4.2 syntax_tools-2.1.3 tools-2.11 wx-1.8.2 xmerl-1.3.15 :
@@ -27,6 +28,7 @@ OTP-19.3.3 : dialyzer-3.1.1 erts-8.3.3 inets-6.3.8 # asn1-4.0.4 common_test-1.14
 OTP-19.3.2 : erts-8.3.2 # asn1-4.0.4 common_test-1.14 compiler-7.0.4 cosEvent-2.2.1 cosEventDomain-1.2.1 cosFileTransfer-1.2.1 cosNotification-1.2.2 cosProperty-1.2.1 cosTime-1.2.2 cosTransactions-1.3.2 crypto-3.7.4 debugger-4.2.1 dialyzer-3.1 diameter-1.12.2 edoc-0.8.1 eldap-1.2.2 erl_docgen-0.6.1 erl_interface-3.9.3 et-1.6 eunit-2.3.2 gs-1.6.2 hipe-3.15.4 ic-4.4.2 inets-6.3.7 jinterface-1.7.1 kernel-5.2 megaco-3.18.1 mnesia-4.14.3 observer-2.3.1 odbc-2.12 orber-3.8.2 os_mon-2.4.2 otp_mibs-1.1.1 parsetools-2.1.4 percept-0.9 public_key-1.4 reltool-0.7.3 runtime_tools-1.11.1 sasl-3.0.3 snmp-5.2.5 ssh-4.4.2 ssl-8.1.2 stdlib-3.3 syntax_tools-2.1.1 tools-2.9.1 typer-0.9.12 wx-1.8 xmerl-1.3.13 :
 OTP-19.3.1 : crypto-3.7.4 erts-8.3.1 inets-6.3.7 ssh-4.4.2 ssl-8.1.2 # asn1-4.0.4 common_test-1.14 compiler-7.0.4 cosEvent-2.2.1 cosEventDomain-1.2.1 cosFileTransfer-1.2.1 cosNotification-1.2.2 cosProperty-1.2.1 cosTime-1.2.2 cosTransactions-1.3.2 debugger-4.2.1 dialyzer-3.1 diameter-1.12.2 edoc-0.8.1 eldap-1.2.2 erl_docgen-0.6.1 erl_interface-3.9.3 et-1.6 eunit-2.3.2 gs-1.6.2 hipe-3.15.4 ic-4.4.2 jinterface-1.7.1 kernel-5.2 megaco-3.18.1 mnesia-4.14.3 observer-2.3.1 odbc-2.12 orber-3.8.2 os_mon-2.4.2 otp_mibs-1.1.1 parsetools-2.1.4 percept-0.9 public_key-1.4 reltool-0.7.3 runtime_tools-1.11.1 sasl-3.0.3 snmp-5.2.5 stdlib-3.3 syntax_tools-2.1.1 tools-2.9.1 typer-0.9.12 wx-1.8 xmerl-1.3.13 :
 OTP-19.3 : common_test-1.14 compiler-7.0.4 crypto-3.7.3 dialyzer-3.1 diameter-1.12.2 erl_interface-3.9.3 erts-8.3 hipe-3.15.4 inets-6.3.6 kernel-5.2 observer-2.3.1 os_mon-2.4.2 public_key-1.4 reltool-0.7.3 runtime_tools-1.11.1 sasl-3.0.3 snmp-5.2.5 ssh-4.4.1 ssl-8.1.1 stdlib-3.3 tools-2.9.1 typer-0.9.12 xmerl-1.3.13 # asn1-4.0.4 cosEvent-2.2.1 cosEventDomain-1.2.1 cosFileTransfer-1.2.1 cosNotification-1.2.2 cosProperty-1.2.1 cosTime-1.2.2 cosTransactions-1.3.2 debugger-4.2.1 edoc-0.8.1 eldap-1.2.2 erl_docgen-0.6.1 et-1.6 eunit-2.3.2 gs-1.6.2 ic-4.4.2 jinterface-1.7.1 megaco-3.18.1 mnesia-4.14.3 odbc-2.12 orber-3.8.2 otp_mibs-1.1.1 parsetools-2.1.4 percept-0.9 syntax_tools-2.1.1 wx-1.8 :
+OTP-19.2.3.1 : erts-8.2.2.1 # asn1-4.0.4 common_test-1.13 compiler-7.0.3 cosEvent-2.2.1 cosEventDomain-1.2.1 cosFileTransfer-1.2.1 cosNotification-1.2.2 cosProperty-1.2.1 cosTime-1.2.2 cosTransactions-1.3.2 crypto-3.7.2 debugger-4.2.1 dialyzer-3.0.3 diameter-1.12.1 edoc-0.8.1 eldap-1.2.2 erl_docgen-0.6.1 erl_interface-3.9.2 et-1.6 eunit-2.3.2 gs-1.6.2 hipe-3.15.3 ic-4.4.2 inets-6.3.5 jinterface-1.7.1 kernel-5.1.1 megaco-3.18.1 mnesia-4.14.3 observer-2.3 odbc-2.12 orber-3.8.2 os_mon-2.4.1 otp_mibs-1.1.1 parsetools-2.1.4 percept-0.9 public_key-1.3 reltool-0.7.2 runtime_tools-1.11 sasl-3.0.2 snmp-5.2.4 ssh-4.4 ssl-8.1 stdlib-3.2 syntax_tools-2.1.1 tools-2.9 typer-0.9.11 wx-1.8 xmerl-1.3.12 :
 OTP-19.2.3 : erts-8.2.2 inets-6.3.5 # asn1-4.0.4 common_test-1.13 compiler-7.0.3 cosEvent-2.2.1 cosEventDomain-1.2.1 cosFileTransfer-1.2.1 cosNotification-1.2.2 cosProperty-1.2.1 cosTime-1.2.2 cosTransactions-1.3.2 crypto-3.7.2 debugger-4.2.1 dialyzer-3.0.3 diameter-1.12.1 edoc-0.8.1 eldap-1.2.2 erl_docgen-0.6.1 erl_interface-3.9.2 et-1.6 eunit-2.3.2 gs-1.6.2 hipe-3.15.3 ic-4.4.2 jinterface-1.7.1 kernel-5.1.1 megaco-3.18.1 mnesia-4.14.3 observer-2.3 odbc-2.12 orber-3.8.2 os_mon-2.4.1 otp_mibs-1.1.1 parsetools-2.1.4 percept-0.9 public_key-1.3 reltool-0.7.2 runtime_tools-1.11 sasl-3.0.2 snmp-5.2.4 ssh-4.4 ssl-8.1 stdlib-3.2 syntax_tools-2.1.1 tools-2.9 typer-0.9.11 wx-1.8 xmerl-1.3.12 :
 OTP-19.2.2 : mnesia-4.14.3 # asn1-4.0.4 common_test-1.13 compiler-7.0.3 cosEvent-2.2.1 cosEventDomain-1.2.1 cosFileTransfer-1.2.1 cosNotification-1.2.2 cosProperty-1.2.1 cosTime-1.2.2 cosTransactions-1.3.2 crypto-3.7.2 debugger-4.2.1 dialyzer-3.0.3 diameter-1.12.1 edoc-0.8.1 eldap-1.2.2 erl_docgen-0.6.1 erl_interface-3.9.2 erts-8.2.1 et-1.6 eunit-2.3.2 gs-1.6.2 hipe-3.15.3 ic-4.4.2 inets-6.3.4 jinterface-1.7.1 kernel-5.1.1 megaco-3.18.1 observer-2.3 odbc-2.12 orber-3.8.2 os_mon-2.4.1 otp_mibs-1.1.1 parsetools-2.1.4 percept-0.9 public_key-1.3 reltool-0.7.2 runtime_tools-1.11 sasl-3.0.2 snmp-5.2.4 ssh-4.4 ssl-8.1 stdlib-3.2 syntax_tools-2.1.1 tools-2.9 typer-0.9.11 wx-1.8 xmerl-1.3.12 :
 OTP-19.2.1 : erts-8.2.1 # asn1-4.0.4 common_test-1.13 compiler-7.0.3 cosEvent-2.2.1 cosEventDomain-1.2.1 cosFileTransfer-1.2.1 cosNotification-1.2.2 cosProperty-1.2.1 cosTime-1.2.2 cosTransactions-1.3.2 crypto-3.7.2 debugger-4.2.1 dialyzer-3.0.3 diameter-1.12.1 edoc-0.8.1 eldap-1.2.2 erl_docgen-0.6.1 erl_interface-3.9.2 et-1.6 eunit-2.3.2 gs-1.6.2 hipe-3.15.3 ic-4.4.2 inets-6.3.4 jinterface-1.7.1 kernel-5.1.1 megaco-3.18.1 mnesia-4.14.2 observer-2.3 odbc-2.12 orber-3.8.2 os_mon-2.4.1 otp_mibs-1.1.1 parsetools-2.1.4 percept-0.9 public_key-1.3 reltool-0.7.2 runtime_tools-1.11 sasl-3.0.2 snmp-5.2.4 ssh-4.4 ssl-8.1 stdlib-3.2 syntax_tools-2.1.1 tools-2.9 typer-0.9.11 wx-1.8 xmerl-1.3.12 :
diff --git a/scripts/build-otp b/scripts/build-otp
index 92a866a0a9..92031c79c8 100755
--- a/scripts/build-otp
+++ b/scripts/build-otp
@@ -37,7 +37,7 @@ if [ ! -d "logs" ]; then
 fi
 
 do_and_log "Autoconfing" autoconf
-do_and_log "Configuring" configure --enable-plain-emulator
+do_and_log "Configuring" configure
 do_and_log "Building OTP" boot -a
 
 exit 0
diff --git a/scripts/run-smoke-tests b/scripts/run-smoke-tests
index 5a850c7107..b3d26f1fce 100755
--- a/scripts/run-smoke-tests
+++ b/scripts/run-smoke-tests
@@ -17,5 +17,3 @@ function run_smoke_tests {
 }
 
 run_smoke_tests
-ERL_FLAGS="-smp disable" run_smoke_tests
-
diff --git a/system/doc/design_principles/gen_server_concepts.xml b/system/doc/design_principles/gen_server_concepts.xml
index c1b98189d5..3a1f876646 100644
--- a/system/doc/design_principles/gen_server_concepts.xml
+++ b/system/doc/design_principles/gen_server_concepts.xml
@@ -32,7 +32,7 @@
   <marker id="gen_server"></marker>
   <p>This section is to be read with the
     <seealso marker="stdlib:gen_server">gen_server(3)</seealso>
-    manual page in <c>stdblib</c>, where all interface functions and
+    manual page in <c>stdlib</c>, where all interface functions and
     callback functions are described in detail.</p>
 
   <section>
diff --git a/system/doc/efficiency_guide/advanced.xml b/system/doc/efficiency_guide/advanced.xml
index bb4440a245..896eda5f1c 100644
--- a/system/doc/efficiency_guide/advanced.xml
+++ b/system/doc/efficiency_guide/advanced.xml
@@ -255,10 +255,11 @@
         <cell><marker id="unique_references"/>Unique References on a Runtime System Instance</cell>
         <cell>Each scheduler thread has its own set of references, and all
         other threads have a shared set of references. Each set of references
-        consist of <c>2⁶⁴ - 1</c> unique references. That is the total
+        consist of <c>2⁶⁴ - 1</c> unique references. That is, the total
         amount of unique references that can be produced on a runtime
-        system instance is <c>(NoSchedulers + 1) * (2⁶⁴ - 1)</c>. If a
-        scheduler thread create a new reference each nano second,
+        system instance is <c>(NoSchedulers + 1) × (2⁶⁴ - 1)</c>.
+	<br/><br/>
+	If a scheduler thread create a new reference each nano second,
         references will at earliest be reused after more than 584 years.
 	That is, for the foreseeable future they are unique enough.</cell>
       </row>
diff --git a/system/doc/reference_manual/errors.xml b/system/doc/reference_manual/errors.xml
index b16c5da6eb..16d3e7590e 100644
--- a/system/doc/reference_manual/errors.xml
+++ b/system/doc/reference_manual/errors.xml
@@ -108,14 +108,55 @@
       (see <seealso marker="#exit_reasons">Exit Reason</seealso>),
       and a stack trace (which aids in finding the code location of
       the exception).</p>
-    <p>The stack trace can be retrieved using
-      <c>erlang:get_stacktrace/0</c>
-      from within a <c>try</c> expression, and is returned for 
+    <p>The stack trace can be be bound to a variable from within
+      a <c>try</c> expression, and is returned for
       exceptions of class <c>error</c> from a <c>catch</c> expression.</p>
     <p>An exception of class <c>error</c> is also known as a run-time 
       error.</p>
+
+      <section>
+	<title>The call-stack back trace (stacktrace)</title>
+        <p>The stack back-trace (<em>stacktrace</em>) is a list of
+          <c>{Module,Function,Arity,Location}</c>
+          tuples. The field <c>Arity</c> in the first tuple can be the
+          argument list of that function call instead of an arity integer,
+          depending on the exception.</p>
+
+	<p><c>Location</c> is a (possibly empty) list of two-tuples
+	that can indicate the location in the source code of the
+	function.  The first element is an atom describing the type of
+	information in the second element. The following items can
+	occur:</p>
+	<taglist>
+          <tag><c>file</c></tag>
+          <item>The second element of the tuple is a string (list of
+          characters) representing the filename of the source file
+          of the function.
+          </item>
+          <tag><c>line</c></tag>
+          <item>The second element of the tuple is the line number
+          (an integer &gt; 0) in the source file
+          where the exception occurred or the function was called.
+          </item>
+	</taglist>
+	<warning><p>Developers should rely on stacktrace entries only for
+	debugging purposes.</p>
+	<p>The VM performs tail call optimization, which
+	does not add new entries to the stacktrace, and also limits stacktraces
+	to a certain depth. Furthermore, compiler options, optimizations and
+	future changes may add or remove stacktrace entries, causing any code
+	that expects the stacktrace to be in a certain order or contain specific
+	items to fail.</p>
+	<p>The only exception to this rule is the class <c>error</c> with the
+	reason <c>undef</c> which is guaranteed to include the <c>Module</c>,
+	<c>Function</c> and <c>Arity</c> of the attempted
+	function as the first stacktrace entry.</p>
+	</warning>
+      </section>
+
   </section>
 
+
   <section>
     <title>Handling of Run-time Errors in Erlang</title>
 
diff --git a/system/doc/reference_manual/expressions.xml b/system/doc/reference_manual/expressions.xml
index cf2d5034aa..94e40dd077 100644
--- a/system/doc/reference_manual/expressions.xml
+++ b/system/doc/reference_manual/expressions.xml
@@ -1340,9 +1340,9 @@ hello</pre>
     <code type="none">
 try Exprs
 catch
-    [Class1:]ExceptionPattern1 [when ExceptionGuardSeq1] ->
+    Class1:ExceptionPattern1[:Stacktrace] [when ExceptionGuardSeq1] ->
         ExceptionBody1;
-    [ClassN:]ExceptionPatternN [when ExceptionGuardSeqN] ->
+    ClassN:ExceptionPatternN[:Stacktrace] [when ExceptionGuardSeqN] ->
         ExceptionBodyN
 end</code>
     <p>This is an enhancement of
@@ -1362,10 +1362,12 @@ end</code>
       the evaluation. In that case the exception is caught and
       the patterns <c>ExceptionPattern</c> with the right exception
       class <c>Class</c> are sequentially matched against the caught
-      exception. An omitted <c>Class</c> is shorthand for <c>throw</c>.
-      If a match succeeds and the optional guard sequence
+      exception. If a match succeeds and the optional guard sequence
       <c>ExceptionGuardSeq</c> is true, the corresponding
       <c>ExceptionBody</c> is evaluated to become the return value.</p>
+    <p><c>Stacktrace</c>, if specified, must be the name of a variable
+      (not a pattern). The stack trace is bound to the variable when
+      the corresponding <c>ExceptionPattern</c> matches.</p>
     <p>If an exception occurs during evaluation of <c>Exprs</c> but
       there is no matching <c>ExceptionPattern</c> of the right
       <c>Class</c> with a true guard sequence, the exception is passed
@@ -1373,6 +1375,18 @@ end</code>
       expression.</p>
     <p>If an exception occurs during evaluation of <c>ExceptionBody</c>,
       it is not caught.</p>
+    <p>It is allowed to omit <c>Class</c> and <c>Stacktrace</c>.
+      An omitted <c>Class</c> is shorthand for <c>throw</c>:</p>
+
+    <code type="none">
+try Exprs
+catch
+    ExceptionPattern1 [when ExceptionGuardSeq1] ->
+        ExceptionBody1;
+    ExceptionPatternN [when ExceptionGuardSeqN] ->
+        ExceptionBodyN
+end</code>
+
     <p>The <c>try</c> expression can have an <c>of</c>
       section:
       </p>
@@ -1384,10 +1398,10 @@ try Exprs of
     PatternN [when GuardSeqN] ->
         BodyN
 catch
-    [Class1:]ExceptionPattern1 [when ExceptionGuardSeq1] ->
+    Class1:ExceptionPattern1[:Stacktrace] [when ExceptionGuardSeq1] ->
         ExceptionBody1;
     ...;
-    [ClassN:]ExceptionPatternN [when ExceptionGuardSeqN] ->
+    ClassN:ExceptionPatternN[:Stacktrace] [when ExceptionGuardSeqN] ->
         ExceptionBodyN
 end</code>
     <p>If the evaluation of <c>Exprs</c> succeeds without an exception,
@@ -1408,10 +1422,10 @@ try Exprs of
     PatternN [when GuardSeqN] ->
         BodyN
 catch
-    [Class1:]ExceptionPattern1 [when ExceptionGuardSeq1] ->
+    Class1:ExceptionPattern1[:Stacktrace] [when ExceptionGuardSeq1] ->
         ExceptionBody1;
     ...;
-    [ClassN:]ExceptionPatternN [when ExceptionGuardSeqN] ->
+    ClassN:ExceptionPatternN[:Stacktrace] [when ExceptionGuardSeqN] ->
         ExceptionBodyN
 after
     AfterBody
@@ -1470,7 +1484,7 @@ try Expr
 catch
     throw:Term -> Term;
     exit:Reason -> {'EXIT',Reason}
-    error:Reason -> {'EXIT',{Reason,erlang:get_stacktrace()}}
+    error:Reason:Stk -> {'EXIT',{Reason,Stk}}
 end</code>
   </section>
 
diff --git a/system/doc/tutorial/port_driver.c b/system/doc/tutorial/port_driver.c
index 37de67310f..8b441733ed 100644
--- a/system/doc/tutorial/port_driver.c
+++ b/system/doc/tutorial/port_driver.c
@@ -51,8 +51,7 @@ ErlDrvEntry example_driver_entry = {
 				   queue */
     NULL,                       /* F_PTR call, much like control, sync call
 				   to driver */
-    NULL,                       /* F_PTR event, called when an event selected 
-				   by driver_event() occurs. */
+    NULL,                       /* unused */
     ERL_DRV_EXTENDED_MARKER,    /* int extended marker, Should always be 
 				   set to indicate driver versioning */
     ERL_DRV_EXTENDED_MAJOR_VERSION, /* int major_version, should always be