Don't build a stacktrace if it's only passed to erlang:raise/3

Consider the following function:

    function({function,Name,Arity,CLabel,Is0}, Lc0) ->
      try
        %% Optimize the code for the function.
      catch
        Class:Error:Stack ->
          io:format("Function: ~w/~w\n", [Name,Arity]),
          erlang:raise(Class, Error, Stack)
      end.

The stacktrace is retrieved, but it is only used in the call
to erlang:raise/3. There is no need to build a stacktrace
in this function. We can avoid the building if we introduce
an instruction called raw_raise/3 that works exactly like
the erlang:raise/3 BIF except that its third argument must
be a raw stacktrace.

1 files changed, 2 insertions, 0 deletions

diff --git a/lib/compiler/src/beam_validator.erl b/lib/compiler/src/beam_validator.erl
index 4feb26c513..22ceef097c 100644
--- a/lib/compiler/src/beam_validator.erl
+++ b/lib/compiler/src/beam_validator.erl
@@ -524,6 +524,8 @@ valfun_4({bif,element,{f,Fail},[Pos,Tuple],Dst}, Vst0) ->
 valfun_4({bif,raise,{f,0},Src,_Dst}, Vst) ->
     validate_src(Src, Vst),
     kill_state(Vst);
+valfun_4(raw_raise=I, Vst) ->
+    call(I, 3, Vst);
 valfun_4({bif,Op,{f,Fail},Src,Dst}, Vst0) ->
     validate_src(Src, Vst0),
     Vst = branch_state(Fail, Vst0),