In-object double fields unboxing (for 64-bit only).

src/code-stubs-hydrogen.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/code-stubs.h"
 #include "src/field-index.h"
 #include "src/hydrogen.h"
 #include "src/lithium.h"
@@ skipping 545 matching lines @@
 
 HLoadNamedField* CodeStubGraphBuilderBase::BuildLoadNamedField(
     HValue* object, FieldIndex index) {
   Representation representation = index.is_double()
       ? Representation::Double()
       : Representation::Tagged();
   int offset = index.offset();
   HObjectAccess access = index.is_inobject()
       ? HObjectAccess::ForObservableJSObjectOffset(offset, representation)
       : HObjectAccess::ForBackingStoreOffset(offset, representation);
-  if (index.is_double()) {
+  if (index.is_double() &&
+      (!FLAG_unbox_double_fields || !index.is_inobject())) {
     // Load the heap number.
     object = Add<HLoadNamedField>(
         object, static_cast<HValue*>(NULL),
         access.WithRepresentation(Representation::Tagged()));
     // Load the double value from it.
     access = HObjectAccess::ForHeapNumberValue();
   }
   return Add<HLoadNamedField>(object, static_cast<HValue*>(NULL), access);
 }
 
@@ skipping 1148 matching lines @@
   return Pop();
 }
 
 
 Handle<Code> KeyedLoadGenericElementStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 
 } }  // namespace v8::internal