Use BuildGrowElementsCapacity for the TransitionElementsKind stub.

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 510 matching lines @@
 }
 
 
 Handle<Code> KeyedStoreFastElementStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 
 template <>
 HValue* CodeStubGraphBuilder<TransitionElementsKindStub>::BuildCodeStub() {
-  Zone* zone = this->zone();
-
   HValue* js_array = GetParameter(0);
   HValue* map = GetParameter(1);
 
   info()->MarkAsSavesCallerDoubles();
 
-  AddInstruction(new(zone) HTrapAllocationMemento(js_array));
+  Add<HTrapAllocationMemento>(js_array);
 
   HInstruction* array_length =
       AddLoad(js_array, HObjectAccess::ForArrayLength());
   array_length->set_type(HType::Smi());
 
-  ElementsKind to_kind = casted_stub()->to_kind();
-  BuildNewSpaceArrayCheck(array_length, to_kind);
-
   IfBuilder if_builder(this);
 
-  if_builder.If<HCompareNumericAndBranch>(array_length,
-                                          graph()->GetConstant0(),
-                                          Token::EQ);
+  if_builder.IfNot<HCompareNumericAndBranch>(array_length,
+                                             graph()->GetConstant0(),
+                                             Token::EQ);
   if_builder.Then();
 
-  // Nothing to do, just change the map.
-
-  if_builder.Else();
-
   HInstruction* elements = AddLoadElements(js_array);
 
   HInstruction* elements_length = AddLoadFixedArrayLength(elements);
 
-  HValue* new_elements = BuildAllocateElementsAndInitializeElementsHeader(
-      context(), to_kind, elements_length);
-
-  BuildCopyElements(context(), elements,
-                    casted_stub()->from_kind(), new_elements,
-                    to_kind, array_length, elements_length);
-
-  AddStore(js_array, HObjectAccess::ForElementsPointer(), new_elements);
+  BuildGrowElementsCapacity(js_array, elements,
+                            casted_stub()->from_kind(),
+                            casted_stub()->to_kind(),
+                            array_length, elements_length);
 
   if_builder.End();
 
   AddStore(js_array, HObjectAccess::ForMap(), map);
 
   return js_array;
 }
 
 
 Handle<Code> TransitionElementsKindStub::GenerateCode() {
@@ skipping 332 matching lines @@
   return value;
 }
 
 
 Handle<Code> StoreGlobalStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 
 } }  // namespace v8::internal