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.

5 files changed, 112 insertions, 1 deletions

diff --git a/lib/hipe/icode/hipe_beam_to_icode.erl b/lib/hipe/icode/hipe_beam_to_icode.erl
index 7ff9fd83eb..6e66ec057c 100644
--- a/lib/hipe/icode/hipe_beam_to_icode.erl
+++ b/lib/hipe/icode/hipe_beam_to_icode.erl
@@ -1164,6 +1164,12 @@ 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)];
+%%--- raw_raise ---
+trans_fun([raw_raise|Instructions], Env) ->
+  Vars = [mk_var({x,0}),mk_var({x,1}),mk_var({x,2})],
+  Dst = [mk_var({x,0})],
+  [hipe_icode:mk_primop(Dst,raw_raise,Vars) |
+   trans_fun(Instructions, Env)];
 %%--------------------------------------------------------------------
 %%--- ERROR HANDLING ---
 %%--------------------------------------------------------------------
diff --git a/lib/hipe/icode/hipe_icode_primops.erl b/lib/hipe/icode/hipe_icode_primops.erl
index 941516e8b1..a1f1128124 100644
--- a/lib/hipe/icode/hipe_icode_primops.erl
+++ b/lib/hipe/icode/hipe_icode_primops.erl
@@ -236,6 +236,7 @@ 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(raw_raise) -> true;
 fails(#mkfun{}) -> false;
 fails(#unsafe_element{}) -> false;
 fails(#unsafe_update_element{}) -> false;
@@ -735,6 +736,8 @@ type(Primop, Args) ->
       erl_types:t_any();
     build_stacktrace ->
       erl_types:t_list();
+    raw_raise ->
+      erl_types:t_atom();
     {M, F, A} ->
       erl_bif_types:type(M, F, A, Args)
   end.
@@ -909,6 +912,8 @@ type(Primop) ->
 %%% Other
     build_stacktrace ->
       erl_types:t_any();
+    raw_raise ->
+      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 cf74c1eb5b..34b18acccd 100644
--- a/lib/hipe/icode/hipe_icode_range.erl
+++ b/lib/hipe/icode/hipe_icode_range.erl
@@ -1187,7 +1187,8 @@ 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(build_stacktrace) -> not_int.
+basic_type(build_stacktrace) -> not_int;
+basic_type(raw_raise) -> not_int.
 
 -spec analyse_bs_get_integer(integer(), integer(), boolean()) -> range_tuple().
 
diff --git a/lib/hipe/rtl/hipe_rtl_primops.erl b/lib/hipe/rtl/hipe_rtl_primops.erl
index d646b78a3d..ce5433379e 100644
--- a/lib/hipe/rtl/hipe_rtl_primops.erl
+++ b/lib/hipe/rtl/hipe_rtl_primops.erl
@@ -396,6 +396,8 @@ gen_primop({Op,Dst,Args,Cont,Fail}, IsGuard, ConstTab) ->
 	    [hipe_rtl:mk_call(Dst, Op, Args, Cont, Fail, not_remote)];
           build_stacktrace ->
 	    [hipe_rtl:mk_call(Dst, Op, Args, Cont, Fail, not_remote)];
+          raw_raise ->
+	    [hipe_rtl:mk_call(Dst, Op, Args, Cont, Fail, not_remote)];
 
 	  %% Only names listed above are accepted! MFA:s are not primops!
 	  _ ->
diff --git a/lib/hipe/test/basic_SUITE_data/basic_exceptions.erl b/lib/hipe/test/basic_SUITE_data/basic_exceptions.erl
index d71b924d22..ba9c03d4ba 100644
--- a/lib/hipe/test/basic_SUITE_data/basic_exceptions.erl
+++ b/lib/hipe/test/basic_SUITE_data/basic_exceptions.erl
@@ -24,6 +24,7 @@ test() ->
   ok = test_bad_fun_call(),
   ok = test_guard_bif(),
   ok = test_eclectic(),
+  ok = test_raise(),
   ok.
 
 %%--------------------------------------------------------------------
@@ -579,3 +580,99 @@ my_add(A, B) ->
 
 my_abs(X) ->
   abs(X).
+
+test_raise() ->
+  test_raise(fun() -> exit({exit,tuple}) end),
+  test_raise(fun() -> abs(id(x)) end),
+  test_raise(fun() -> throw({was,thrown}) end),
+
+  badarg = bad_raise(fun() -> abs(id(x)) end),
+
+  ok.
+
+bad_raise(Expr) ->
+  try
+    Expr()
+  catch
+    _:E:Stk ->
+      erlang:raise(bad_class, E, Stk)
+  end.
+
+test_raise(Expr) ->
+  test_raise_1(Expr),
+  test_raise_2(Expr),
+  test_raise_3(Expr).
+
+test_raise_1(Expr) ->
+  erase(exception),
+  try
+    do_test_raise_1(Expr)
+  catch
+    C:E:Stk ->
+      {C,E,Stk} = erase(exception)
+  end.
+
+do_test_raise_1(Expr) ->
+  try
+    Expr()
+  catch
+    C:E:Stk ->
+      %% Here the stacktrace must be built.
+      put(exception, {C,E,Stk}),
+      erlang:raise(C, E, Stk)
+  end.
+
+test_raise_2(Expr) ->
+  erase(exception),
+  try
+    do_test_raise_2(Expr)
+  catch
+    C:E:Stk ->
+      {C,E} = erase(exception),
+      try
+        Expr()
+      catch
+        _:_:S ->
+          [StkTop|_] = S,
+          [StkTop|_] = Stk
+      end
+  end.
+
+do_test_raise_2(Expr) ->
+  try
+    Expr()
+  catch
+    C:E:Stk ->
+      %% Here it is possible to replace erlang:raise/3 with
+      %% the raw_raise/3 instruction since the stacktrace is
+      %% not actually used.
+      put(exception, {C,E}),
+      erlang:raise(C, E, Stk)
+  end.
+
+test_raise_3(Expr) ->
+  try
+    do_test_raise_3(Expr)
+  catch
+    exit:{exception,C,E}:Stk ->
+      try
+        Expr()
+      catch
+        C:E:S ->
+          [StkTop|_] = S,
+          [StkTop|_] = Stk
+      end
+  end.
+
+do_test_raise_3(Expr) ->
+  try
+    Expr()
+  catch
+    C:E:Stk ->
+      %% Here it is possible to replace erlang:raise/3 with
+      %% the raw_raise/3 instruction since the stacktrace is
+      %% not actually used.
+      erlang:raise(exit, {exception,C,E}, Stk)
+  end.
+
+id(I) -> I.