Optimizing nested, constant object literals (like JSON objects) by building o...

src/codegen-ia32.cc

 // Copyright 2006-2008 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 3414 matching lines @@
   frame_->Push(&boilerplate);
   // Clone the boilerplate object.
   Result clone =
       frame_->CallRuntime(Runtime::kCloneObjectLiteralBoilerplate, 1);
   // Push the newly cloned literal object as the result.
   frame_->Push(&clone);
 
   for (int i = 0; i < node->properties()->length(); i++) {
     ObjectLiteral::Property* property = node->properties()->at(i);
     switch (property->kind()) {
-      case ObjectLiteral::Property::CONSTANT: break;
+      case ObjectLiteral::Property::CONSTANT:
+        break;
+      case ObjectLiteral::Property::OBJECT_LITERAL:
+        if (property->value()->AsObjectLiteral()->is_simple()) break;
       case ObjectLiteral::Property::COMPUTED: {
         Handle<Object> key(property->key()->handle());
         Handle<Code> ic(Builtins::builtin(Builtins::StoreIC_Initialize));
         if (key->IsSymbol()) {
           // Duplicate the object as the IC receiver.
           frame_->Dup();
           Load(property->value());
           Result value = frame_->Pop();
           value.ToRegister(eax);
 
@@ skipping 3370 matching lines @@
 
   // Slow-case: Go through the JavaScript implementation.
   __ bind(&slow);
   __ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_FUNCTION);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal