implement fast ReturnValue setters

src/api.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 6189 matching lines @@
       i::Vector<const char>(data, length));
   i::Handle<i::Symbol> result = i_isolate->factory()->NewSymbol();
   result->set_name(*name);
   return Utils::ToLocal(result);
 }
 
 
 Local<Number> v8::Number::New(double value) {
   i::Isolate* isolate = i::Isolate::Current();
   EnsureInitializedForIsolate(isolate, "v8::Number::New()");
+  return Number::New(reinterpret_cast<Isolate*>(isolate), value);
+}
+
+
+Local<Number> v8::Number::New(Isolate* isolate, double value) {
+  i::Isolate* internal_isolate = reinterpret_cast<i::Isolate*>(isolate);
+  ASSERT(internal_isolate->IsInitialized());
   if (std::isnan(value)) {
     // Introduce only canonical NaN value into the VM, to avoid signaling NaNs.
     value = i::OS::nan_value();
   }
-  ENTER_V8(isolate);
-  i::Handle<i::Object> result = isolate->factory()->NewNumber(value);
+  ENTER_V8(internal_isolate);
+  i::Handle<i::Object> result = internal_isolate->factory()->NewNumber(value);
   return Utils::NumberToLocal(result);
 }
 
 
 Local<Integer> v8::Integer::New(int32_t value) {
   i::Isolate* isolate = i::Isolate::UncheckedCurrent();
   EnsureInitializedForIsolate(isolate, "v8::Integer::New()");
   return v8::Integer::New(value, reinterpret_cast<Isolate*>(isolate));
 }
 
@@ skipping 1641 matching lines @@
 
   v->VisitPointers(blocks_.first(), first_block_limit_);
 
   for (int i = 1; i < blocks_.length(); i++) {
     v->VisitPointers(blocks_[i], &blocks_[i][kHandleBlockSize]);
   }
 }
 
 
 } }  // namespace v8::internal