Separated smi check from HBoundsCheck.

src/code-stubs-hydrogen.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 159 matching lines @@
                                               HType::Smi()));
 
   Heap* heap = isolate()->heap();
   const int kMinFreeNewSpaceAfterGC =
       ((heap->InitialSemiSpaceSize() - sizeof(FixedArrayBase)) / 2) /
       kDoubleSize;
 
   HConstant* max_alloc_size =
       new(zone) HConstant(kMinFreeNewSpaceAfterGC, Representation::Integer32());
   AddInstruction(max_alloc_size);
-  AddInstruction(new(zone) HBoundsCheck(array_length, max_alloc_size));
+  AddInstruction(

[Jakob Kummerow, 2013/02/07 16:17:14]

Please add a comment here:
// Since we're forcing Integer32 representation for this HBoundsCheck,
// there's no need to Smi-check the index.

[Massi, 2013/02/11 10:35:55]

Done.

+      new(zone) HBoundsCheck(array_length, max_alloc_size,
+                             DONT_ALLOW_SMI_KEY, Representation::Integer32()));
 
   current_block()->UpdateEnvironment(new(zone) HEnvironment(zone));
 
   IfBuilder if_builder(this);
 
   if_builder.BeginTrue(array_length, graph()->GetConstant0(), Token::EQ);
 
   // Nothing to do, just change the map.
 
   if_builder.BeginFalse();
@@ skipping 53 matching lines @@
 
 
 Handle<Code> TransitionElementsKindStub::GenerateCode() {
   CodeStubGraphBuilder<TransitionElementsKindStub> builder(this);
   LChunk* chunk = OptimizeGraph(builder.CreateGraph());
   return chunk->Codegen(Code::COMPILED_STUB);
 }
 
 
 } }  // namespace v8::internal