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2015-04-29beam_validator: Stop validating the 'aligned' flag for binariesBjörn Gustavsson
The run-time system stopped paying attention the 'aligned' flag in bit syntax construction and matching when bitstrings were introduced in language. The beam_asm compiler pass will crash if the 'aligned' flag is given in bit syntax instructions. beam_validator still validates the 'aligned' flag. Before 912fea0b712a (which removed the possibility to validate existing BEAM files), the 'aligned' flag could actually be encountered when validating a BEAM file. Since the validation of 'aligned' no longer serves any useful purpose, remove the validation code.
2015-04-29beam_validator: Clean up updating of types for y registerBjörn Gustavsson
set_type_y/3 is far too complicated. Note that we don't need to check the #st.numy field, because we will detect the error anyway because the information for the y register will be missing in the #st.y gb_tree. There is also a clause that would never match because of a spelling error (the first "n" was missing in "uninitialized"). That clause is not needed because the default clause will do fine. Furthermore, we can break out the special case for handling catch_end and similar instructions into a new function.
2015-04-23beam_validator: Remove support for removed BIF fault/1,2Björn Gustavsson
The fault/1,2 BIF was removed a long time ago.
2015-04-23beam_validator: Correct merging of statesBjörn Gustavsson
When merging two states, the following fields should be merged between the states: #st.x, #st.y, #st.numy, #st.ct. Everything else should be set to the default values in a new state.
2015-04-23beam_validator: Correct merging of y registersBjörn Gustavsson
When merging y registers, only the y registers that are found in both states should be retained.
2015-04-22sys_pre_expand: Remove unused fields in #expand{} recordBjörn Gustavsson
The compile, bitdefault, and bittypes records are not really used in the #expand{} record.
2015-04-22v3_life: Optimize updating of the variable data baseBjörn Gustavsson
Updating of the variable data base takes most of the time.
2015-04-22beam_jump: Replace use of lists:dropwhile/2 with a custom functionBjörn Gustavsson
The use of lists:dropwhile/2 is noticeable in the eprof results.
2015-04-22beam_asm: Eliminate unnecessary use of iolist_to_binary/1Björn Gustavsson
2015-04-22beam_bsm: Optimize btb_index()Björn Gustavsson
lists:dropwhile/2 and the fun in btb_index_1/2 shows up in the top 10 list of eprof. Replace dropwhile with a special-purpose function for a tiny increase in speed.
2015-04-22beam_type: Eliminate redundant calls to checkerror_1/2Björn Gustavsson
Profiling shows that the excution time for checkerror_1/2 could be be near the top even for modules without any floating point operations. It turns out that the complexity of simplify_float_1/4 is quadratic. checkerror/1 is called with the growing accumulator for each iteration. checkerror/1 will traverse the entire accumulated list *unless* some floating point operations are used. We can avoid this situation if we only call checkerror/1 when there are live floating point registers. We can also avoid calling flush/3 if there are no live floating point registers.
2015-04-22beam_utils: Optimize index_labels_1/2Björn Gustavsson
The execution time for beam_utils:index_labels_1/2 is among the longest in the beam_bool, beam_bsm, beam_receive, and beam_trim compiler passes. Therefore it is worthwhile to do the minor optimization of replacing a call to lists:dropwhile/2 with a special-purpose drop_labels function.
2015-04-22beam_block: Optimize matching of binary literalsBjörn Gustavsson
When matching a binary literal as in: <<"abc">> = Bin the compiler will produce a sequence of three instructions (some details in the instructions removed for simplicity): bs_start_match2 Fail BinReg CtxtReg bs_match_string Fail CtxtReg "abc" bs_test_tail2 Fail CtxtReg 0 The sequence can be replaced with: is_eq_exact Fail BinReg "abc"
2015-04-22Move rewriting of bs_match from beam_clean to beam_zBjörn Gustavsson
The actual bs_match_string instruction has four operands: bs_match_string {f,Lbl} Ctxt NumBits {string,ListOfBytes} However, v3_codegen emits a more compact representation where the bits to match are packaged in a bitstring: bs_match_string {f,Lbl} Ctxt Bitstring Currently, beam_clean:clean_labels/1 will rewrite the compact representation to the final representation. That is unfortunate since clean_labels/1 is called by beam_dead, which means that the less compact representation will be introduced long before it is actually needed by beam_asm. It will also complicate any optimizations that we might want to do. Move the rewriting of bs_match_string from beam_clean:clean_labels/1 to the beam_z pass, which is the last pass executed before beam_validator and beam_asm.
2015-04-22v3_codegen: Reduce cost for fixing up bs_match_string instructionsBjörn Gustavsson
Commit b76588fb5a introduced an optimization of the compile time of huge functions with many bs_match_string instructions. The optimization is done in two passes. The first pass coalesces adjacent bs_match_string instructions. To avoid copying bitstrings multiple times, the bitstrings in the instructions are combined in to a (deep) list. The second pass goes through all instructions in the function and combines the list of bitstrings to a single bitstring in all bs_match_string instructions. The second pass (fix_bs_match_string) is run on all instructions in each function, even if there are no bs_match_instructions in the function. While fix_bs_match_string is not a bottleneck (it is a linear pass), its execution time is noticeable when profiling some modules. Move the execution of the second pass to the select_binary() function so that it will only be executed for instructions that do binary matching. Also take the opportunity to optimize away uses of bs_restore2 that occour directly after a bs_save2. That optimimization is currently done in beam_block, but it can be done essentially for free in the same pass that fixes up bs_match_string instructions.
2015-04-22v3_codegen: Optimize "turning" of y registersBjörn Gustavsson
Profiling shows that the execution time for "turning" y registers is noticeable for some modules (e.g. S1AP-PDU-Contents from the asn1 test suite). We can reduce the impact on running time by special-casing important instructions. In particular, there is no need to look for y registers in the list argument for a select_val instruction.
2015-04-22v3_kernel: Optimize subst_vsub/3Björn Gustavsson
Profiling shows that subst_vsub/3 dominates the running time. It is therefore worthwhile optimizing it.
2015-04-22compile: Add the {eprof,Pass} option for easy eprof runningBjörn Gustavsson
To run eprof for a compiler pass: erlc +'{eprof,beam_asm}' file.erl The name of the compiler pass is the name as printed when 'time' option is used. It is usually, but not always, the module name for the compiler pass.
2015-04-22compile: Eliminate unnecessary wrappers for compiler passesBjörn Gustavsson
Several compiler passes have unnecessary wrapper functions that can be easily eliminated.
2015-04-15Raise more descriptive error messages for failed map operationsBjörn Gustavsson
According to EEP-43 for maps, a 'badmap' exception should be generated when an attempt is made to update non-map term such as: <<>>#{a=>42} That was not implemented in the OTP 17. José Valim suggested that we should take the opportunity to improve the errors coming from map operations: http://erlang.org/pipermail/erlang-questions/2015-February/083588.html This commit implement better errors from map operations similar to his suggestion. When a map update operation (Map#{...}) or a BIF that expects a map is given a non-map term, the exception will be: {badmap,Term} This kind of exception is similar to the {badfun,Term} exception from operations that expect a fun. When a map operation requires a key that is not present in a map, the following exception will be raised: {badkey,Key} José Valim suggested that the exception should be {badkey,Key,Map}. We decided not to do that because the map could potentially be huge and cause problems if the error propagated through links to other processes. For BIFs, it could be argued that the exceptions could be simply 'badmap' and 'badkey', because the bad map and bad key can be found in the argument list for the BIF in the stack backtrace. However, for the map update operation (Map#{...}), the bad map or bad key will not be included in the stack backtrace, so that information must be included in the exception reason itself. For consistency, the BIFs should raise the same exceptions as update operation. If more than one key is missing, it is undefined which of keys that will be reported in the {badkey,Key} exception.
2015-04-13v3_codegen: Don't sort map keys in map creation/updateBjörn Gustavsson
It is no longer necessary to sort the keys, since the loader does the sorting.
2015-04-13beam_validator: No longer require strict literal term orderBjörn Gustavsson
The BEAM loader will now sort keys for maps during loading, so beam_validator should not require the keys to be ordered any order. However, we must still ensure that literals keys are unique (which was implicitly guaranteed by the strict ordering requirement).
2015-03-25Merge branch 'bjorn/doc'Björn Gustavsson
* bjorn/doc: cerl_trees: Fix incorrect EDoc reference to the cerl module cerl: Correct incorrect EDoc references
2015-03-24cerl_trees: Fix incorrect EDoc reference to the cerl moduleBjörn Gustavsson
2015-03-20Merge branch 'rickard/time_api/OTP-11997'Rickard Green
* rickard/time_api/OTP-11997: (22 commits) Update primary bootstrap inets: Suppress deprecated warning on erlang:now/0 inets: Cleanup of multiple copies of functions Add inets_lib with common functions used by multiple modules inets: Update comments Suppress deprecated warning on erlang:now/0 Use new time API and be back-compatible in inets Remove unused functions and removed redundant test asn1 test SUITE: Eliminate use of now/0 Disable deprecated warning on erlang:now/0 in diameter_lib Use new time API and be back-compatible in ssh Replace all calls to now/0 in CT with new time API functions test_server: Replace usage of erlang:now() with usage of new API Replace usage of erlang:now() with usage of new API Replace usage of erlang:now() with usage of new API Replace usage of erlang:now() with usage of new API Replace usage of erlang:now() with usage of new API otp_SUITE: Warn for calls to erlang:now/0 Replace usage of erlang:now() with usage of new API Multiple timer wheels Erlang based BIF timer implementation for scalability Implement ethread events with timeout ... Conflicts: bootstrap/bin/start.boot bootstrap/bin/start_clean.boot bootstrap/lib/compiler/ebin/beam_asm.beam bootstrap/lib/compiler/ebin/compile.beam bootstrap/lib/kernel/ebin/auth.beam bootstrap/lib/kernel/ebin/dist_util.beam bootstrap/lib/kernel/ebin/global.beam bootstrap/lib/kernel/ebin/hipe_unified_loader.beam bootstrap/lib/kernel/ebin/inet_db.beam bootstrap/lib/kernel/ebin/inet_dns.beam bootstrap/lib/kernel/ebin/inet_res.beam bootstrap/lib/kernel/ebin/os.beam bootstrap/lib/kernel/ebin/pg2.beam bootstrap/lib/stdlib/ebin/dets.beam bootstrap/lib/stdlib/ebin/dets_utils.beam bootstrap/lib/stdlib/ebin/erl_tar.beam bootstrap/lib/stdlib/ebin/escript.beam bootstrap/lib/stdlib/ebin/file_sorter.beam bootstrap/lib/stdlib/ebin/otp_internal.beam bootstrap/lib/stdlib/ebin/qlc.beam bootstrap/lib/stdlib/ebin/random.beam bootstrap/lib/stdlib/ebin/supervisor.beam bootstrap/lib/stdlib/ebin/timer.beam erts/aclocal.m4 erts/emulator/beam/bif.c erts/emulator/beam/erl_bif_info.c erts/emulator/beam/erl_db_hash.c erts/emulator/beam/erl_init.c erts/emulator/beam/erl_process.h erts/emulator/beam/erl_thr_progress.c erts/emulator/beam/utils.c erts/emulator/sys/unix/sys.c erts/preloaded/ebin/erlang.beam erts/preloaded/ebin/erts_internal.beam erts/preloaded/ebin/init.beam erts/preloaded/src/erts_internal.erl lib/common_test/test/ct_hooks_SUITE_data/cth/tests/empty_cth.erl lib/diameter/src/base/diameter_lib.erl lib/kernel/src/os.erl lib/ssh/test/ssh_basic_SUITE.erl system/doc/efficiency_guide/advanced.xml
2015-03-20Replace usage of erlang:now() with usage of new APIRickard Green
2015-03-19cerl: Correct incorrect EDoc referencesBjörn Gustavsson
Change c_nil/1 to c_nil/0. Change c_try/3 to c_try/5. Change c_var_name/1 to var_name/1.
2015-03-11v3_life: Combine literal/2 and literal2/2Björn Gustavsson
For unclear reasons, there are two functions in v3_life that are almost identical: literal/2 and literal2/2. literal/2 is used for expressions and literal2/2 for patterns. It turns out that literal2/2 can do everything that literal/2 can do, except that it transforms maps differently. If we adjust v3_codegen to accept the same format of maps in expressions and patterns, we can rename literal2/2 to literal/2 and use it for expressions and patterns.
2015-03-09v3_codegen: Don't save options in the process dictionaryBjörn Gustavsson
v3_codegen puts the compilation in the process dictionary, but never uses them.
2015-03-09Don't inline core_parseBjörn Gustavsson
Inlining the core_parse module is slow (the inline pass alone takes more than 6 seconds on my computer) and has no benefit.
2015-03-09v3_core: Teach pat_alias/2 to eliminate duplicated variablesBjörn Gustavsson
Duplicated variables as aliases in patterns, such as: f({_,_}=Dup=Dup) -> ... will work, but produce sub-optimal code similar to: f({_,_}=Dup=NewVar) when Dup =:= NewVar -> ... with one extra guard test for each duplicated variable. Rewrite pat_alias/2 to eliminate all duplicated variables. While we are at it, also simplify handling of tuples, conses, and literals by using the data functions in the cerl module.
2015-03-09beam_dead: Improve optimization by eliminating fallthroughsBjörn Gustavsson
2015-03-09beam_dead: Optimize Var =:= VarBjörn Gustavsson
2015-03-09beam_peep: Optimize away redundant use of is_boolean testsBjörn Gustavsson
2015-03-09beam_bool: Correct initialized_regs/2Björn Gustavsson
initialized_regs/2 did not handle allocating instructions; instead treating them as any other 'set' instruction. The consequences could be one or both of the following: Going past the allocating instruction (looking at more instructions) would mean that initialized_regs/2 could return registers that were not actually initialized. That could mean that MustBeKilled in ensure_opt_safe/6 could contain too few registers, and that the code that followed tried to use an uninitialized register. The beam_validator should have detected that problem. Not taking account the number of live registers in the allocating instruction could mean that some registers were not found to be initialized, which could mean that MustBeKilled would contain too many registers. That would mean a missed optimization.
2015-03-09sys_core_fold: Generalize case optimizationBjörn Gustavsson
For a long time, there has been an optimization for: {V1,V2,...} = case Expr of Pat -> ... {Val1,Val2,...}; ... end that avoids building the tuples. The construct looks like this in Core Erlang: let <V> = case X of Pattern -> {Y,Z} end in case V of {A,B} -> A+B end The current optimization will try to replace the second 'case' with a 'let': let <A,B> = case X of Pattern -> <Y,Z> end in A+B Simple variations of the construct would prevent the optimizations; for example this one: let <V> = case X of Pattern -> {'ok',Val} end in case V of {ok,Val} -> Val end The problem is that the optimization tries to do too much. By making the optimization do less and have it depend on other optimizations to finish the job, it will become more powerful. Thus we can rewrite the code like this: let <V1,V2> = case X of Pattern -> <'ok',Val> end in let <V> = {V1,V2} in case V of {ok,Val} -> Val end Note that the second case is unchanged. The other optimizations in the sys_core_fold module will optimize the second 'case' and eliminate the building of the tuple.
2015-03-09sys_core_fold: Improve optimization of 'not'Björn Gustavsson
Optimize away 'not' in sys_core_fold instead of in beam_block and beam_dead, as we can do a better job in sys_core_fold. I modified the test suite temporarily to never turn off Core Erlang modifications and looked at the coverage. With the new optimizations active in sys_core_fold, the code in beam_block and beam_dead did not find a single 'not' that it could optimize. That proves that the new optimization is at least as good as the old one. Manually, I could also verify that the new optimization would optimize some variations of 'not' that the old one would not handle.
2015-03-09sys_core_fold: Suppress compiler warnings when evaluating element/2Björn Gustavsson
More aggressive optimizations that we plan to introduce could cause spurious compiler warnings.
2015-03-09Clean up evaluation of setelement/3Björn Gustavsson
The 'try' ... 'catch' is problematic. Firstly, if no optimization is possible, an exception will always be thrown. Secondly, bugs in the code will go unnoticed.
2015-03-09Replace '==' with '=:=' when both operands are integersBjörn Gustavsson
'=:=' is a cheaper operation than '==', so we should always use '=:=' if the result will be the same as if '==' were used.
2015-03-09Update type information based on BIFs that returns integersBjörn Gustavsson
2015-03-09sys_core_fold: Strengthen type optimization in letsBjörn Gustavsson
Make sure that we take extract all possible type information when optimizing a 'let' construct. Since the stronger optimization may generate false warnings, we also need to take special care to suppress false warnings.
2015-03-09v3_codegen: Teach the put_map_* instructions to reuse source registersBjörn Gustavsson
The put_map_assoc and put_map_exact instructions in the run-time system will support that the target register is the same as one of the source registers. Teach the code generator to take advantage of that. The disadvantages of not reusing register when possible is that the garbage collector may retain dead terms longer than necessary.
2015-03-09beam_validator: Tighten tests of mapsBjörn Gustavsson
2015-03-09v3_core: Eliminate the sloppiness-encouraging get_ianno/1 functionBjörn Gustavsson
get_ianno/1 would retrieve either a bare annotation or an annotation wrapped in an #a{} record. In both cases, it would return a wrapped annotation. We can replace the calls to get_ianno/1 with calls to get_anno/1, because the argument is always an #iclause{} and all iclause records are always initialized with a wrapped annotation.
2015-03-09v3_core: Add is_map tests before map instructionsBjörn Gustavsson
If we have a sequence of put_map_* instructions operating on the same map, it will be more efficient if we can have one is_map/2 instruction before put_map_* instructions, so that each put_map_* does not need to test whether the argument is a map.
2015-03-09beam_type: Use the complete register map when calculating livenessBjörn Gustavsson
When calculating the number of live registers for allocation instruction, it is not always safe to start with the number of live registers at the start of the block. We will need to use the register map to know whether there are any holes (dead registers) that are not subsequently filled. If the allocation instruction already has a number of live registers calculated, there is nothing to be gained by raising it.
2015-03-09Introduce '%live' annotations with a complete register mapBjörn Gustavsson
As a preparation for fixing a bug, introduce a complete register map in the '%live' annotations.
2015-02-27beam_validator: Teach bif_type/3 and is_bif_safe/2 about is_map/1Björn Gustavsson
2015-02-27v3_core: Simplify conversion of map patternsBjörn Gustavsson