Reintroduce sensitive BIFs in erl_bif_types

This involves exception BIF's, guar BIF's and some other complicated BIF's
Also some minor corrections to documentation and specs in erlang.erl
Added comment for each spec in erlang.erl shadowed by erl_bif_types.

Dialyzer test should now run well except for one or two cases.

4 files changed, 215 insertions, 26 deletions

diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index 7838cffded..e5ea517492 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -3191,7 +3191,8 @@ os_prompt%</pre>
       <type name="priority_level"/>
       <fsummary>Set process flag priority for the calling process</fsummary>
       <desc>
-        <p>This sets the process priority. <c><anno>Level</anno></c> is an atom.
+        <p><marker id="process_flag_priority"></marker>
+          This sets the process priority. <c><anno>Level</anno></c> is an atom.
           There are currently four priority levels: <c>low</c>,
           <c>normal</c>, <c>high</c>, and <c>max</c>. The default
           priority level is <c>normal</c>. <em>NOTE</em>: The
@@ -3333,6 +3334,8 @@ os_prompt%</pre>
     <func>
       <name name="process_info" arity="1"/>
       <type name="process_info_result_item"/>
+      <type name="priority_level"/>
+      <type name="stack_item"/>
       <fsummary>Information about a process</fsummary>
       <desc>
         <p>Returns a list containing <c><anno>InfoTuple</anno></c>s with
@@ -3889,7 +3892,7 @@ true</pre>
         <p>Starts a timer which will send the message <c>Msg</c>
           to <c><anno>Dest</anno></c> after <c><anno>Time</anno></c> milliseconds.</p>
 	<p>If <c><anno>Dest</anno></c> is a <c>pid()</c> it has to be a <c>pid()</c> of a local process, dead or alive.</p>
-	<p>The <c><anno>Time</anno></c> value can, in the current implementation, not be grater than 4294967295.</p>
+	<p>The <c><anno>Time</anno></c> value can, in the current implementation, not be greater than 4294967295.</p>
         <p>If <c><anno>Dest</anno></c> is an <c>atom()</c>, it is supposed to be the name of
           a registered process. The process referred to by the name is
           looked up at the time of delivery. No error is given if
@@ -4314,7 +4317,7 @@ true</pre>
           <c>{timeout, <anno>TimerRef</anno>, <anno>Msg</anno>}</c> to <c><anno>Dest</anno></c>
           after <c><anno>Time</anno></c> milliseconds.</p>
 	<p>If <c><anno>Dest</anno></c> is a <c>pid()</c> it has to be a <c>pid()</c> of a local process, dead or alive.</p>
-	<p>The <c><anno>Time</anno></c> value can, in the current implementation, not be grater than 4294967295.</p>
+	<p>The <c><anno>Time</anno></c> value can, in the current implementation, not be greater than 4294967295.</p>
         <p>If <c><anno>Dest</anno></c> is an <c>atom()</c>, it is supposed to be the name of
           a registered process. The process referred to by the name is
           looked up at the time of delivery. No error is given if
@@ -4345,7 +4348,8 @@ true</pre>
       <name name="statistics" arity="1" clause_i="2"/>
       <fsummary>Information about exact reductions</fsummary>
       <desc>
-        <p><em>NOTE:</em> <c>statistics(exact_reductions)</c> is
+        <p><marker id="statistics_exact_reductions"></marker>
+          <em>NOTE:</em> <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>
@@ -4371,7 +4375,8 @@ true</pre>
       <name name="statistics" arity="1" clause_i="5"/>
       <fsummary>Information about reductions</fsummary>
       <desc>
-        <p><em>NOTE:</em> From erts version 5.5 (OTP release R11B)
+        <p><marker id="statistics_reductions"></marker>
+          <em>NOTE:</em> From erts version 5.5 (OTP release R11B)
           this value does not include reductions performed in current
           time slices of currently scheduled processes. If an
           exact value is wanted, use
@@ -4525,12 +4530,14 @@ true</pre>
       <name name="system_flag" arity="2" clause_i="2"/>
       <type name="cpu_topology"/>
       <type name="level_entry"/>
-      <type name="sub_level"/>
       <type name="level_tag"/>
+      <type name="sub_level"/>
+      <type name="info_list"/>
       <fsummary>Set system flag cpu_topology</fsummary>
       <desc>
         <warning>
-          <p>This argument is <em>deprecated</em> and
+          <p><marker id="system_flag_cpu_topology"></marker>
+          This argument is <em>deprecated</em> and
           scheduled for removal in erts-5.10/OTP-R16. Instead of using
           this argument you are advised to use the <c>erl</c> command
           line argument <seealso marker="erts:erl#+sct">+sct</seealso>.
@@ -4616,7 +4623,8 @@ true</pre>
       <name name="system_flag" arity="2" clause_i="6"/>
       <fsummary>Set system flag multi_scheduling</fsummary>
       <desc>
-        <p>If multi-scheduling is enabled, more than one scheduler
+        <p><marker id="system_flag_multi_scheduling"></marker>
+          If multi-scheduling is enabled, more than one scheduler
           thread is used by the emulator. Multi-scheduling can be
           blocked. When multi-scheduling has been blocked, only
           one scheduler thread will schedule Erlang processes.</p>
@@ -4655,7 +4663,8 @@ true</pre>
       <fsummary>Set system flag scheduler_bind_type</fsummary>
       <desc>
         <warning>
-          <p>This argument is <em>deprecated</em> and
+          <p><marker id="system_flag_scheduler_bind_type"></marker>
+          This argument is <em>deprecated</em> and
           scheduled for removal in erts-5.10/OTP-R16. Instead of using
           this argument you are advised to use the <c>erl</c> command
           line argument <seealso marker="erts:erl#+sbt">+sbt</seealso>.
@@ -4772,7 +4781,8 @@ true</pre>
       <name name="system_flag" arity="2" clause_i="8"/>
       <fsummary>Set system flag schedulers_online</fsummary>
       <desc>
-        <p>Sets the amount of schedulers online. Valid range is
+        <p><marker id="system_flag_schedulers_online"></marker>
+        Sets the amount of schedulers online. Valid range is
         <![CDATA[1 <= SchedulersOnline <= erlang:system_info(schedulers)]]>.
         </p>
         <p>Returns the old value of the flag.</p>
@@ -4932,6 +4942,7 @@ true</pre>
       <type name="cpu_topology"/>
       <type name="level_entry"/>
       <type_desc name="cpu_topology">
+        <marker id="system_info_cpu_topology"></marker>
         All <c><anno>LevelEntry</anno></c>s of a list
         must contain the same <c><anno>LevelTag</anno></c>, except
         on the top level where both <c>node</c> and
@@ -4956,7 +4967,7 @@ true</pre>
           of the current system
           (emulator) as specified by <c><anno>Item</anno></c>:</p>
         <taglist>
-          <tag><marker id="system_info_cpu_topology"><c>cpu_topology</c></marker></tag>
+          <tag><c>cpu_topology</c></tag>
           <item>
 	    <p>Returns the <c><anno>CpuTopology</anno></c> which currently is used by the
 	       emulator. The CPU topology is used when binding schedulers
@@ -6188,6 +6199,8 @@ true</pre>
       <name name="trace_info" arity="2"/>
       <type name="trace_info_return"/>
       <type name="trace_info_item_result"/>
+      <type name="trace_info_flag"/>
+      <type name="trace_match_spec"/>
       <fsummary>Trace information about a process or function</fsummary>
       <desc>
         <p>Returns trace information about a process or function.</p>
diff --git a/erts/preloaded/ebin/erlang.beam b/erts/preloaded/ebin/erlang.beam
index c44f05f87d..01246a34da 100644
--- a/erts/preloaded/ebin/erlang.beam
+++ b/erts/preloaded/ebin/erlang.beam
diff --git a/erts/preloaded/src/erlang.erl b/erts/preloaded/src/erlang.erl
index b1b2156ad5..65ebe83c3a 100644
--- a/erts/preloaded/src/erlang.erl
+++ b/erts/preloaded/src/erlang.erl
@@ -117,7 +117,7 @@
          is_record/3, is_reference/1, is_tuple/1, load_module/2,
          load_nif/2, localtime_to_universaltime/2, make_fun/3,
          make_tuple/2, make_tuple/3, nodes/1, open_port/2,
-         port_call/3, port_info/1, port_info/2, process_flag/2,
+         port_call/2, port_call/3, port_info/1, port_info/2, process_flag/2,
          process_info/2, send/2, send/3, seq_trace_info/1,
          setelement/3, spawn_opt/1,
 	 statistics/1, subtract/2, system_flag/2,
@@ -579,12 +579,14 @@ erase(_Key) ->
     erlang:nif_error(undefined).
 
 % error/1
+%% Shadowed by erl_bif_types: erlang:error/1
 -spec error(Reason) -> no_return() when
       Reason :: term().
 error(_Reason) ->
     erlang:nif_error(undefined).
 
 % error/2
+%% Shadowed by erl_bif_types: erlang:error/2
 -spec error(Reason, Args) -> no_return() when
       Reason :: term(),
       Args :: [term()].
@@ -592,6 +594,7 @@ error(_Reason, _Args) ->
     erlang:nif_error(undefined).
 
 % exit/1
+%% Shadowed by erl_bif_types: erlang:exit/1
 -spec exit(Reason) -> no_return() when
       Reason :: term().
 exit(_Reason) ->
@@ -719,11 +722,13 @@ group_leader(_GroupLeader, _Pid) ->
     erlang:nif_error(undefined).
 
 % halt/0
+%% Shadowed by erl_bif_types: erlang:halt/0
 -spec halt() -> no_return().
 halt() ->
     erlang:nif_error(undefined).
 
 % halt/1
+%% Shadowed by erl_bif_types: erlang:halt/1
 -spec halt(Status) -> no_return() when
       Status :: non_neg_integer() | string().
 halt(_Status) ->
@@ -934,12 +939,14 @@ monitor_node(_Node, _Flag, _Options) ->
     erlang:nif_error(undefined).
 
 % nif_error/1
+%% Shadowed by erl_bif_types: erlang:nif_error/1
 -spec erlang:nif_error(Reason) -> no_return() when
       Reason :: term().
 nif_error(_Reason) ->
     erlang:nif_error(undefined).
 
 % nif_error/2
+%% Shadowed by erl_bif_types: erlang:nif_error/2
 -spec erlang:nif_error(Reason, Args) -> no_return() when
       Reason :: term(),
       Args :: [term()].
@@ -1293,6 +1300,7 @@ system_profile(_ProfilerPid, _Options) ->
     erlang:nif_error(undefined).
 
 % throw/1
+%% Shadowed by erl_bif_types: erlang:throw/1
 -spec throw(Any) -> no_return() when
       Any :: term().
 throw(_Any) ->
@@ -1380,6 +1388,7 @@ whereis(_RegName) ->
 
 %% types and specs
 
+%% Shadowed by erl_bif_types: erlang:abs/1
 -spec abs(Float) -> float() when
       Float :: float();
          (Int) -> non_neg_integer() when
@@ -1388,12 +1397,14 @@ abs(_Number) ->
     erlang:nif_error(undefined).
 
 %% Not documented
+%% Shadowed by erl_bif_types: erlang:append/2
 -spec erlang:append(List,Tail) -> maybe_improper_list() when
       List :: [term()],
       Tail :: term().
 append(_List,_Tail) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:element/2
 -spec element(N, Tuple) -> term() when
     N :: pos_integer(),
     Tuple :: tuple().
@@ -1408,6 +1419,7 @@ element(_N, _Tuple) ->
 get_module_info(_Module, _Item) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:hd/1
 -spec hd(List) -> term() when
       List :: [term(), ...].
 hd(_List) ->
@@ -1415,73 +1427,87 @@ hd(_List) ->
 
 %% erlang:info/1 no longer exists!
 
+%% Shadowed by erl_bif_types: erlang:is_atom/1
 -spec is_atom(Term) -> boolean() when
       Term :: term().
 is_atom(_Term) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_binary/1
 -spec is_binary(Term) -> boolean() when
       Term :: term().
 is_binary(_Term) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_bitstring/1
 -spec is_bitstring(Term) -> boolean() when
       Term :: term().
 is_bitstring(_Term) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_boolean/1
 -spec is_boolean(Term) -> boolean() when
       Term :: term().
 is_boolean(_Term) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_float/1
 -spec is_float(Term) -> boolean() when
       Term :: term().
 is_float(_Term) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_function/1
 -spec is_function(Term) -> boolean() when
       Term :: term().
 is_function(_Term) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_function/2
 -spec is_function(Term, Arity) -> boolean() when
       Term :: term(),
       Arity :: arity().
 is_function(_Term, _Arity) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_integer/1
 -spec is_integer(Term) -> boolean() when
       Term :: term().
 is_integer(_Term) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_list/1
 -spec is_list(Term) -> boolean() when
       Term :: term().
 is_list(_Term) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_number/1
 -spec is_number(Term) -> boolean() when
       Term :: term().
 is_number(_Term) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_pid/1
 -spec is_pid(Term) -> boolean() when
       Term :: term().
 is_pid(_Term) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_port/1
 -spec is_port(Term) -> boolean() when
       Term :: term().
 is_port(_Term) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_record/2
 -spec is_record(Term,RecordTag) -> boolean() when
       Term :: term(),
       RecordTag :: atom().
 is_record(_Term,_RecordTag) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_record/3
 -spec is_record(Term,RecordTag,Size) -> boolean() when
       Term :: term(),
       RecordTag :: atom(),
@@ -1489,11 +1515,13 @@ is_record(_Term,_RecordTag) ->
 is_record(_Term,_RecordTag,_Size) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_reference/1
 -spec is_reference(Term) -> boolean() when
       Term :: term().
 is_reference(_Term) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:is_tuple/1
 -spec is_tuple(Term) -> boolean() when
       Term :: term().
 is_tuple(_Term) ->
@@ -1531,12 +1559,14 @@ localtime_to_universaltime(_Localtime, _IsDst) ->
 make_fun(_Module,_Function, _Arity) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:make_tuple/2
 -spec erlang:make_tuple(Arity, InitialValue) -> tuple() when
       Arity :: arity(),
       InitialValue :: term().
 make_tuple(_Arity,_InitialValue) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:make_tuple/3
 -spec erlang:make_tuple(Arity, DefaultValue, InitList) -> tuple() when
       Arity :: arity(),
       DefaultValue :: term(),
@@ -1575,6 +1605,14 @@ nodes(_Arg) ->
 open_port(_PortName,_PortSettings) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:port_call/2
+-spec erlang:port_call(Port, Data) -> term() when
+      Port :: port() | atom(),
+      Data :: term().
+port_call(_Port, _Data) ->
+    erlang:nif_error(undefined).
+
+%% Shadowed by erl_bif_types: erlang:port_call/3
 -spec erlang:port_call(Port, Operation, Data) -> term() when
       Port :: port() | atom(),
       Operation :: integer(),
@@ -1600,16 +1638,18 @@ port_call(_Port, _Operation, _Data) ->
       {input, Bytes :: non_neg_integer()} |
       {output, Bytes :: non_neg_integer()}.
 
+%% Shadowed by erl_bif_types: erlang:port_info/1
 -spec erlang:port_info(Port) -> Result when
       Port :: port() | atom(),
       Result :: [port_info_result_item()] | undefined.
 port_info(_Result) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:port_info/2
 -spec erlang:port_info(Port, Item) -> Result when
       Port :: port() | atom(),
       Item :: port_info_item(),
-      Result :: port_info_result_item() | undefined | [].
+      Result :: port_info_result_item() | undefined.
 port_info(_Result, _Item) ->
     erlang:nif_error(undefined).
 
@@ -1689,7 +1729,7 @@ process_flag(_Flag, _Value) ->
       {current_location,
        {Module :: module(), Function :: atom(), Arity :: arity(),
         Location :: [{file, Filename :: string()} | % not a stack_item()!
-                     {line, Line :: integer()}]}} |
+                     {line, Line :: pos_integer()}]}} |
       {current_stacktrace, Stack :: [stack_item()]} |
       {dictionary, Dictionary :: [{Key :: term(), Value :: term()}]} |
       {error_handler, Module :: module()} |
@@ -1728,7 +1768,7 @@ process_flag(_Flag, _Value) ->
          Function :: atom(),
          Arity :: arity() | (Args :: [term()]),
          Location :: [{file, Filename :: string()} |
-                      {line, Line :: integer()}]}.
+                      {line, Line :: pos_integer()}]}.
 
 -spec process_info(Pid, Item) ->
                           InfoTuple | [] | undefined when
@@ -1744,7 +1784,7 @@ process_flag(_Flag, _Value) ->
 process_info(_Pid,_ItemSpec) ->
     erlang:nif_error(undefined).
 
--spec send(Dest, Msg) -> Msg when
+-spec erlang:send(Dest, Msg) -> Msg when
       Dest :: dst(),
       Msg :: term().
 send(_Dest,_Msg) ->
@@ -1768,6 +1808,7 @@ send(_Dest,_Msg,_Options) ->
 seq_trace_info(_What) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:setelement/3
 -spec setelement(Index, Tuple1, Value) -> Tuple2 when
       Index :: pos_integer(),
       Tuple1 :: tuple(),
@@ -1817,6 +1858,7 @@ statistics(_Item) ->
     erlang:nif_error(undefined).
 
 %% Not documented
+%% Shadowed by erl_bif_types: erlang:subtract/2
 -spec erlang:subtract([term()], [term()]) -> [term()].
 subtract(_,_) ->
     erlang:nif_error(undefined).
@@ -1881,6 +1923,7 @@ term_to_binary(_Term) ->
 term_to_binary(_Term, _Options) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:tl/1
 -spec tl(List) -> term() when
       List :: [term(), ...].
 tl(_List) ->
@@ -1916,6 +1959,7 @@ trace_pattern(_MFA, _MatchSpec) ->
 trace_pattern(_MFA, _MatchSpec, _FlagList) ->
     erlang:nif_error(undefined).
 
+%% Shadowed by erl_bif_types: erlang:tuple_to_list/1
 -spec tuple_to_list(Tuple) -> [term()] when
       Tuple :: tuple().
 tuple_to_list(_Tuple) ->
@@ -1934,6 +1978,7 @@ tuple_to_list(_Tuple) ->
 -type info_list() :: [].
 
 %% Note: changing the ordering number of a clause will change the docs!
+%% Shadowed by erl_bif_types: erlang:system_info/1
 -spec erlang:system_info
          (allocated_areas) -> [ tuple() ];
          (allocator) ->
@@ -2031,6 +2076,7 @@ universaltime_to_localtime(_Universaltime) ->
 apply(Fun, Args) ->
     erlang:apply(Fun, Args).
 
+%% Shadowed by erl_bif_types: erlang:apply/3
 -spec apply(Module, Function, Args) -> term() when
       Module :: module(),
       Function :: atom(),
diff --git a/lib/hipe/cerl/erl_bif_types.erl b/lib/hipe/cerl/erl_bif_types.erl
index 190f14a474..b822f182c2 100644
--- a/lib/hipe/cerl/erl_bif_types.erl
+++ b/lib/hipe/cerl/erl_bif_types.erl
@@ -63,6 +63,7 @@
 		    t_fun/2,
 		    t_fun_args/1,
 		    t_fun_range/1,
+		    t_identifier/0,
 		    t_inf/2,
 		    t_integer/0,
 		    t_integer/1,
@@ -138,6 +139,12 @@ type(M, F, A) ->
 -spec type(atom(), atom(), arity(), [erl_types:erl_type()]) -> erl_types:erl_type().
 
 %%-- erlang -------------------------------------------------------------------
+type(erlang, halt, 0, _) -> t_none();
+type(erlang, halt, 1, _) -> t_none();
+type(erlang, exit, 1, _) -> t_none();
+type(erlang, error, 1, _) -> t_none();
+type(erlang, error, 2, _) -> t_none();
+type(erlang, throw, 1, _) -> t_none();
 type(erlang, '==', 2, Xs = [X1, X2]) ->
   case t_is_atom(X1) andalso t_is_atom(X2) of
     true -> type(erlang, '=:=', 2, Xs);
@@ -489,6 +496,9 @@ type(erlang, 'bnot', 1, Xs) ->
 	       {ok, T} -> T
 	     end
 	 end);
+%% Guard bif, needs to be here.
+type(erlang, abs, 1, Xs) ->
+  strict(arg_types(erlang, abs, 1), Xs, fun ([X]) -> X end);
 %% This returns (-X)-1, so it often gives a negative result.
 %%  strict(arg_types(erlang, 'bnot', 1), Xs, fun (_) -> t_integer() end);
 type(erlang, append, 2, Xs) -> type(erlang, '++', 2, Xs); % alias
@@ -504,8 +514,24 @@ type(erlang, apply, 2, Xs) ->
   strict(arg_types(erlang, apply, 2), Xs, Fun);
 type(erlang, apply, 3, Xs) ->
   strict(arg_types(erlang, apply, 3), Xs, fun (_) -> t_any() end);
+%% Guard bif, needs to be here.
+type(erlang, binary_part, 2, Xs) ->
+  strict(arg_types(erlang, binary_part, 2), Xs, fun (_) -> t_binary() end);
+%% Guard bif, needs to be here.
+type(erlang, binary_part, 3, Xs) ->
+  strict(arg_types(erlang, binary_part, 3), Xs, fun (_) -> t_binary() end);
+%% Guard bif, needs to be here.
+type(erlang, bit_size, 1, Xs) ->
+  strict(arg_types(erlang, bit_size, 1), Xs,
+	 fun (_) -> t_non_neg_integer() end);
+%% Guard bif, needs to be here.
+type(erlang, byte_size, 1, Xs) ->
+  strict(arg_types(erlang, byte_size, 1), Xs,
+	 fun (_) -> t_non_neg_integer() end);
 type(erlang, disconnect_node, 1, Xs) ->
   strict(arg_types(erlang, disconnect_node, 1), Xs, fun (_) -> t_sup([t_boolean(), t_atom('ignored')]) end);
+%% Guard bif, needs to be here.
+%% Also much more expressive than anything you could write in a spec...
 type(erlang, element, 2, Xs) ->
   strict(arg_types(erlang, element, 2), Xs,
 	 fun ([X1, X2]) ->
@@ -529,16 +555,22 @@ type(erlang, element, 2, Xs) ->
 		 t_sup([type(erlang, element, 2, [X1, Y]) || Y <- Ts])
 	     end
 	 end);
+%% Guard bif, needs to be here.
+type(erlang, float, 1, Xs) ->
+  strict(arg_types(erlang, float, 1), Xs, fun (_) -> t_float() end);
 type(erlang, fun_info, 1, Xs) ->
   strict(arg_types(erlang, fun_info, 1), Xs,
 	 fun (_) -> t_list(t_tuple([t_atom(), t_any()])) end);
 type(erlang, get_cookie, 0, _) -> t_atom();  % | t_atom('nocookie')
+%% Guard bif, needs to be here.
 type(erlang, hd, 1, Xs) ->
   strict(arg_types(erlang, hd, 1), Xs, fun ([X]) -> t_cons_hd(X) end);
 type(erlang, integer_to_list, 2, Xs) ->
   strict(arg_types(erlang, integer_to_list, 2), Xs,
 	 fun (_) -> t_string() end);
 type(erlang, info, 1, Xs) -> type(erlang, system_info, 1, Xs); % alias
+%% All type tests are guard BIF's and may be implemented in ways that
+%% cannot be expressed in a type spec, why they are kept in erl_bif_types.
 type(erlang, is_atom, 1, Xs) ->   
   Fun = fun (X) -> check_guard(X, fun (Y) -> t_is_atom(Y) end, t_atom()) end,
   strict(arg_types(erlang, is_atom, 1), Xs, Fun);
@@ -702,6 +734,9 @@ type(erlang, is_tuple, 1, Xs) ->
 	    check_guard(X, fun (Y) -> t_is_tuple(Y) end, t_tuple())
 	end,
   strict(arg_types(erlang, is_tuple, 1), Xs, Fun);
+%% Guard bif, needs to be here.
+type(erlang, length, 1, Xs) ->
+  strict(arg_types(erlang, length, 1), Xs, fun (_) -> t_non_neg_fixnum() end);
 type(erlang, list_to_integer, 2, Xs) ->
   strict(arg_types(erlang, list_to_integer, 2), Xs,
 	 fun (_) -> t_integer() end);
@@ -726,12 +761,47 @@ type(erlang, nif_error, 1, _) ->
   t_any();   % this BIF and the next one are stubs for NIFs and never return
 type(erlang, nif_error, 2, Xs) ->
   strict(arg_types(erlang, nif_error, 2), Xs, fun (_) -> t_any() end);
+%% Guard bif, needs to be here.
+type(erlang, node, 0, _) -> t_node();
+%% Guard bif, needs to be here.
+type(erlang, node, 1, Xs) ->
+  strict(arg_types(erlang, node, 1), Xs, fun (_) -> t_node() end);
 type(erlang, nodes, 0, _) -> t_list(t_node());
 type(erlang, port_call, Arity, Xs) when Arity =:= 2; Arity =:= 3 ->
   strict(arg_types(erlang, port_call, Arity), Xs, fun (_) -> t_any() end);
 type(erlang, port_info, 1, Xs) ->
   strict(arg_types(erlang, port_info, 1), Xs,
 	 fun (_) -> t_sup(t_atom('undefined'), t_list()) end);
+type(erlang, port_info, 2, Xs) ->
+  strict(arg_types(erlang, port_info, 2), Xs,
+	 fun ([_Port, Item]) ->
+	     t_sup(t_atom('undefined'),
+		   case t_atom_vals(Item) of
+		     ['connected'] -> t_tuple([Item, t_pid()]);
+		     ['id'] -> t_tuple([Item, t_integer()]);
+		     ['input'] -> t_tuple([Item, t_integer()]);
+		     ['links'] -> t_tuple([Item, t_list(t_pid())]);
+		     ['name'] -> t_tuple([Item, t_string()]);
+		     ['output'] -> t_tuple([Item, t_integer()]);
+		     ['registered_name'] -> t_tuple([Item, t_atom()]);
+		     List when is_list(List) ->
+		       t_tuple([t_sup([t_atom(A) || A <- List]),
+				t_sup([t_atom(), t_integer(),
+				       t_pid(), t_list(t_pid()),
+				       t_string()])]);
+		     unknown ->
+		       [_, PosItem] = arg_types(erlang, port_info, 2),
+		       t_tuple([PosItem,
+				t_sup([t_atom(), t_integer(),
+				       t_pid(), t_list(t_pid()),
+				       t_string()])])		       
+		   end)
+	 end);
+%% Guard bif, needs to be here.
+type(erlang, round, 1, Xs) ->
+  strict(arg_types(erlang, round, 1), Xs, fun (_) -> t_integer() end);
+%% Guard bif, needs to be here.
+type(erlang, self, 0, _) -> t_pid();
 type(erlang, set_cookie, 2, Xs) ->
   strict(arg_types(erlang, set_cookie, 2), Xs, fun (_) -> t_atom('true') end);
 type(erlang, setelement, 3, Xs) ->
@@ -765,6 +835,9 @@ type(erlang, setelement, 3, Xs) ->
 		 t_sup([type(erlang, setelement, 3, [X1, Y, X3]) || Y <- Ts])
 	     end
 	 end);
+%% Guard bif, needs to be here.
+type(erlang, size, 1, Xs) ->
+  strict(arg_types(erlang, size, 1), Xs, fun (_) -> t_non_neg_integer() end);
 type(erlang, spawn, 1, Xs) ->
   strict(arg_types(erlang, spawn, 1), Xs, fun (_) -> t_pid() end);
 type(erlang, spawn, 2, Xs) ->
@@ -894,13 +967,15 @@ type(erlang, system_info, 1, Xs) ->
 		 t_any() %% overapproximation as the return value might change
 	     end
 	 end);
-type(erlang, term_to_binary, 1, Xs) ->
-  strict(arg_types(erlang, term_to_binary, 1), Xs, fun (_) -> t_binary() end);
+%% Guard bif, needs to be here.
 type(erlang, tl, 1, Xs) ->
   strict(arg_types(erlang, tl, 1), Xs, fun ([X]) -> t_cons_tl(X) end);
-type(erlang, trace_pattern, 2, Xs) ->
-  strict(arg_types(erlang, trace_pattern, 2), Xs,
-	 fun (_) -> t_non_neg_fixnum() end); %% num of MFAs that match pattern
+%% Guard bif, needs to be here.
+type(erlang, trunc, 1, Xs) ->
+  strict(arg_types(erlang, trunc, 1), Xs, fun (_) -> t_integer() end);
+%% Guard bif, needs to be here.
+type(erlang, tuple_size, 1, Xs) ->
+  strict(arg_types(erlang, tuple_size, 1), Xs, fun (_) -> t_non_neg_integer() end);
 type(erlang, tuple_to_list, 1, Xs) ->
   strict(arg_types(erlang, tuple_to_list, 1), Xs,
 	 fun ([X]) ->
@@ -2092,6 +2167,9 @@ arg_types(erlang, 'bsl', 2) ->
   [t_integer(), t_integer()];
 arg_types(erlang, 'bnot', 1) ->
   [t_integer()];
+%% Guard bif, needs to be here.
+arg_types(erlang, abs, 1) ->
+  [t_number()];
 arg_types(erlang, append, 2) ->
   arg_types(erlang, '++', 2);
 arg_types(erlang, apply, 2) ->
@@ -2101,14 +2179,41 @@ arg_types(erlang, apply, 2) ->
    t_list()];
 arg_types(erlang, apply, 3) ->
   [t_sup(t_atom(), t_tuple()), t_atom(), t_list()];
+%% Guard bif, needs to be here.
+arg_types(erlang, binary_part, 2) ->
+  [t_binary(), t_tuple([t_non_neg_integer(), t_integer()])];
+%% Guard bif, needs to be here.
+arg_types(erlang, binary_part, 3) ->
+  [t_binary(), t_non_neg_integer(), t_integer()];
+%% Guard bif, needs to be here.
+arg_types(erlang, bit_size, 1) ->
+  [t_bitstr()];
+%% Guard bif, needs to be here.
+arg_types(erlang, byte_size, 1) ->
+  [t_binary()];
 arg_types(erlang, disconnect_node, 1) ->
   [t_node()];
+arg_types(erlang, halt, 0) ->
+  [];
+arg_types(erlang, halt, 1) ->
+  [t_sup(t_non_neg_fixnum(), t_string())];
+arg_types(erlang, error, 1) ->
+  [t_any()];
+arg_types(erlang, error, 2) ->
+  [t_any(), t_list()];
+arg_types(erlang, exit, 1) ->
+  [t_any()];
+%% Guard bif, needs to be here.
 arg_types(erlang, element, 2) ->
   [t_pos_fixnum(), t_tuple()];
+%% Guard bif, needs to be here.
+arg_types(erlang, float, 1) ->
+  [t_number()];
 arg_types(erlang, fun_info, 1) ->
   [t_fun()];
 arg_types(erlang, get_cookie, 0) ->
   [];
+%% Guard bif, needs to be here.
 arg_types(erlang, hd, 1) ->
   [t_cons()];
 arg_types(erlang, info, 1) ->
@@ -2149,6 +2254,9 @@ arg_types(erlang, is_reference, 1) ->
   [t_any()];
 arg_types(erlang, is_tuple, 1) ->
   [t_any()];
+%% Guard bif, needs to be here.
+arg_types(erlang, length, 1) ->
+  [t_list()];
 arg_types(erlang, list_to_integer, 2) ->
   [t_list(t_byte()), t_from_range(2, 36)];
 arg_types(erlang, make_tuple, 2) ->
@@ -2161,6 +2269,12 @@ arg_types(erlang, nif_error, 1) ->
   [t_any()];
 arg_types(erlang, nif_error, 2) ->
   [t_any(), t_list()];
+%% Guard bif, needs to be here.
+arg_types(erlang, node, 0) ->
+  [];
+%% Guard bif, needs to be here.
+arg_types(erlang, node, 1) ->
+  [t_identifier()];
 arg_types(erlang, nodes, 0) ->
   [];
 arg_types(erlang, port_call, 2) ->
@@ -2169,10 +2283,23 @@ arg_types(erlang, port_call, 3) ->
   [t_sup(t_port(), t_atom()), t_integer(), t_any()];
 arg_types(erlang, port_info, 1) ->
   [t_sup(t_port(), t_atom())];
+arg_types(erlang, port_info, 2) ->
+  [t_sup(t_port(), t_atom()),
+   t_atoms(['registered_name', 'id', 'connected',
+	    'links', 'name', 'input', 'output'])];
+%% Guard bif, needs to be here.
+arg_types(erlang, round, 1) ->
+  [t_number()];
+%% Guard bif, needs to be here.
+arg_types(erlang, self, 0) ->
+  [];
 arg_types(erlang, set_cookie, 2) ->
   [t_node(), t_atom()];
 arg_types(erlang, setelement, 3) ->
   [t_pos_integer(), t_tuple(), t_any()];
+%% Guard bif, needs to be here.
+arg_types(erlang, size, 1) ->
+  [t_sup(t_tuple(), t_binary())];
 arg_types(erlang, spawn, 1) -> %% TODO: Tuple?
   [t_fun()];
 arg_types(erlang, spawn, 2) -> %% TODO: Tuple?
@@ -2194,14 +2321,17 @@ arg_types(erlang, system_info, 1) ->
 	  t_tuple([t_atom(), t_any()]), % documented
 	  t_tuple([t_atom(), t_atom(), t_any()]),
 	  t_tuple([t_atom(allocator_sizes), t_reference(), t_any()])])];
-arg_types(erlang, term_to_binary, 1) ->
+arg_types(erlang, throw, 1) ->
   [t_any()];
+%% Guard bif, needs to be here.
 arg_types(erlang, tl, 1) ->
   [t_cons()];
-arg_types(erlang, trace_pattern, 2) ->
-  [t_sup(t_tuple([t_atom(), t_atom(), t_sup(t_arity(), t_atom('_'))]),
-	 t_atom('on_load')),
-   t_sup([t_boolean(), t_list(), t_atom('restart'), t_atom('pause')])];
+%% Guard bif, needs to be here.
+arg_types(erlang, trunc, 1) ->
+  [t_number()];
+%% Guard bif, needs to be here.
+arg_types(erlang, tuple_size, 1) ->
+  [t_tuple()];
 arg_types(erlang, tuple_to_list, 1) ->
   [t_tuple()];
 arg_types(erlang, yield, 0) ->