Merge branch 'bg/compiler-beam_validator' into ccase/r13b04_dev

* bg/compiler-beam_validator:
  beam_validator: fix incorrect assumptions about GC guard BIFs

OTP-8378  In rare circumstances when using garbaging collecting guard BIFs,
          the validation pass (beam_validator) would signal that the code
          was unsafe, when it in fact was correct. (Thanks to Kiran
          Khaladkar.)

1 files changed, 8 insertions, 8 deletions

diff --git a/lib/compiler/src/beam_validator.erl b/lib/compiler/src/beam_validator.erl
index 08ba9c3ee4..1fd61831e0 100644
--- a/lib/compiler/src/beam_validator.erl
+++ b/lib/compiler/src/beam_validator.erl
@@ -1,19 +1,19 @@
 %%
 %% %CopyrightBegin%
-%% 
-%% Copyright Ericsson AB 2004-2009. All Rights Reserved.
-%% 
+%%
+%% Copyright Ericsson AB 2004-2010. All Rights Reserved.
+%%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
 %% compliance with the License. You should have received a copy of the
 %% Erlang Public License along with this software. If not, it can be
 %% retrieved online at http://www.erlang.org/.
-%% 
+%%
 %% Software distributed under the License is distributed on an "AS IS"
 %% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 %% the License for the specific language governing rights and limitations
 %% under the License.
-%% 
+%%
 %% %CopyrightEnd%
 
 -module(beam_validator).
@@ -604,9 +604,9 @@ valfun_4({gc_bif,Op,{f,Fail},Live,Src,Dst}, #vst{current=St0}=Vst0) ->
     St = kill_heap_allocation(St0),
     Vst1 = Vst0#vst{current=St},
     verify_live(Live, Vst1),
-    Vst2 = prune_x_regs(Live, Vst1),
-    validate_src(Src, Vst2),
-    Vst = branch_state(Fail, Vst2),
+    Vst2 = branch_state(Fail, Vst1),
+    Vst = prune_x_regs(Live, Vst2),
+    validate_src(Src, Vst),
     Type = bif_type(Op, Src, Vst),
     set_type_reg(Type, Dst, Vst);
 valfun_4(return, #vst{current=#st{numy=none}}=Vst) ->