Do not internalize in TryConvertKey.

src/ic.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 965 matching lines @@
   if (key->IsHeapNumber()) {
     double value = Handle<HeapNumber>::cast(key)->value();
     if (std::isnan(value)) {
       key = isolate->factory()->nan_string();
     } else {
       int int_value = FastD2I(value);
       if (value == int_value && Smi::IsValid(int_value)) {
         key = Handle<Smi>(Smi::FromInt(int_value), isolate);
       }
     }
-  } else if (key->IsString()) {
-    key = isolate->factory()->InternalizeString(Handle<String>::cast(key));
   } else if (key->IsUndefined()) {
     key = isolate->factory()->undefined_string();
   }
   return key;
 }
 
 
 Handle<Code> KeyedLoadIC::LoadElementStub(Handle<JSObject> receiver) {
   // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS
   // via megamorphic stubs, since they don't have a map in their relocation info
@@ skipping 58 matching lines @@
 
 
 MaybeObject* KeyedLoadIC::Load(Handle<Object> object, Handle<Object> key) {
   if (MigrateDeprecated(object)) {
     return Runtime::GetObjectPropertyOrFail(isolate(), object, key);
   }
 
   MaybeObject* maybe_object = NULL;
   Handle<Code> stub = generic_stub();
 
-  // Check for values that can be converted into an internalized string directly
-  // or is representable as a smi.
+  // Check for non-string values that can be converted into an
+  // internalized string directly or is representable as a smi.
   key = TryConvertKey(key, isolate());
 
   if (key->IsInternalizedString()) {
     maybe_object = LoadIC::Load(object, Handle<String>::cast(key));
     if (maybe_object->IsFailure()) return maybe_object;
   } else if (FLAG_use_ic && !object->IsAccessCheckNeeded()) {
     ASSERT(!object->IsJSGlobalProxy());
     if (object->IsString() && key->IsNumber()) {
       if (state() == UNINITIALIZED) stub = string_stub();
     } else if (object->IsJSObject()) {
@@ skipping 575 matching lines @@
   if (MigrateDeprecated(object)) {
     Handle<Object> result = Runtime::SetObjectProperty(isolate(), object,
                                                        key,
                                                        value,
                                                        NONE,
                                                        strict_mode());
     RETURN_IF_EMPTY_HANDLE(isolate(), result);
     return *result;
   }
 
-  // Check for values that can be converted into an internalized string directly
-  // or is representable as a smi.
+  // Check for non-string values that can be converted into an
+  // internalized string directly or is representable as a smi.
   key = TryConvertKey(key, isolate());
 
   MaybeObject* maybe_object = NULL;
   Handle<Code> stub = generic_stub();
 
   if (key->IsInternalizedString()) {
     maybe_object = StoreIC::Store(object,
                                   Handle<String>::cast(key),
                                   value,
                                   JSReceiver::MAY_BE_STORE_FROM_KEYED);
@@ skipping 1142 matching lines @@
 #undef ADDR
 };
 
 
 Address IC::AddressFromUtilityId(IC::UtilityId id) {
   return IC_utilities[id];
 }
 
 
 } }  // namespace v8::internal