Use hydrogen accessor instead of copying members.

src/ia32/lithium-ia32.cc

 // Copyright 2010 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 1267 matching lines @@
     }
   }
   return new LBranch(UseRegisterAtStart(v), first_id, second_id);
 }
 
 
 LInstruction* LChunkBuilder::DoCompareMapAndBranch(
     HCompareMapAndBranch* instr) {
   ASSERT(instr->value()->representation().IsTagged());
   LOperand* value = UseRegisterAtStart(instr->value());
-  HBasicBlock* first = instr->FirstSuccessor();
-  HBasicBlock* second = instr->SecondSuccessor();
-  return new LCmpMapAndBranch(value,
-                              instr->map(),
-                              first->block_id(),
-                              second->block_id());
+  return new LCmpMapAndBranch(value);
 }
 
 
 LInstruction* LChunkBuilder::DoArgumentsLength(HArgumentsLength* length) {
   return DefineAsRegister(new LArgumentsLength(Use(length->value())));
 }
 
 
 LInstruction* LChunkBuilder::DoArgumentsElements(HArgumentsElements* elems) {
   return DefineAsRegister(new LArgumentsElements);
@@ skipping 813 matching lines @@
 void LPointerMap::PrintTo(StringStream* stream) const {
   stream->Add("{");
   for (int i = 0; i < pointer_operands_.length(); ++i) {
     if (i != 0) stream->Add(";");
     pointer_operands_[i]->PrintTo(stream);
   }
   stream->Add("} @%d", position());
 }
 
 } }  // namespace v8::internal