Faster access to isolated worlds.

bindings/v8/V8IsolatedWorld.h

 /*
  * Copyright (C) 2009 Google Inc. 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
@@ skipping 67 matching lines @@
         //
         static V8IsolatedWorld* getEntered()
         {
             // This is a temporary performance optimization.   Essentially,
             // GetHiddenValue is too slow for this code path.  We need to get the
             // V8 team to add a real property to v8::Context for isolated worlds.
             // Until then, we optimize the common case of not having any isolated
             // worlds at all.
             if (!isolatedWorldCount)
                 return 0;
-            return getEnteredImpl();
+            if (!v8::Context::InContext())
+                return 0;
+            return reinterpret_cast<V8IsolatedWorld*>(getGlobalObject(v8::Context::GetEntered())->GetPointerFromInternalField(V8Custom::kDOMWindowEnteredIsolatedWorldIndex));
         }
 
         v8::Handle<v8::Context> context() { return m_context->get(); }
         PassRefPtr<SharedPersistent<v8::Context> > sharedContext() { return m_context; }
 
         DOMDataStore* getDOMDataStore() const { return m_domDataStore.getStore(); }
 
     private:
-        static V8IsolatedWorld* getEnteredImpl();
+        static v8::Handle<v8::Object> getGlobalObject(v8::Handle<v8::Context> context)
+        {
+            return v8::Handle<v8::Object>::Cast(context->Global()->GetPrototype());
+        }
 
         // Called by the garbage collector when our JavaScript context is about
         // to be destroyed.
         static void contextWeakReferenceCallback(v8::Persistent<v8::Value> object, void* isolated_world);
 
         // The v8::Context for the isolated world.  This object is keep on the
         // heap as long as |m_context| has not been garbage collected.
         RefPtr<SharedPersistent<v8::Context> > m_context;
 
         // The backing store for the isolated world's DOM wrappers.  This class
         // doesn't have visibility into the wrappers.  This handle simply helps
         // manage their lifetime.
         DOMDataStoreHandle m_domDataStore;
 
         static int isolatedWorldCount;
     };
 
 } // namespace WebCore
 
 #endif // V8IsolatedWorld_h