Share optimized code for closures.

src/hydrogen-instructions.h

 // 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 1443 matching lines @@
   }
 
   HValue* argument() { return OperandAt(0); }
 
   DECLARE_CONCRETE_INSTRUCTION(PushArgument)
 };
 
 
 class HThisFunction: public HTemplateInstruction<0> {
  public:
-  explicit HThisFunction(Handle<JSFunction> closure) : closure_(closure) {
+  HThisFunction() {
     set_representation(Representation::Tagged());
     SetFlag(kUseGVN);
   }
 
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::None();
   }
 
-  Handle<JSFunction> closure() const { return closure_; }
-
   DECLARE_CONCRETE_INSTRUCTION(ThisFunction)
 
  protected:
-  virtual bool DataEquals(HValue* other) {
-    HThisFunction* b = HThisFunction::cast(other);
-    return *closure() == *b->closure();
-  }
-
- private:
-  Handle<JSFunction> closure_;
+  virtual bool DataEquals(HValue* other) { return true; }
 };
 
 
 class HContext: public HTemplateInstruction<0> {
  public:
   HContext() {
     set_representation(Representation::Tagged());
     SetFlag(kUseGVN);
   }
 
@@ skipping 3464 matching lines @@
   DECLARE_CONCRETE_INSTRUCTION(LoadFieldByIndex);
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_