Experimental: thread the virtual frame through the deferred code...

src/codegen.h

 // 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 70 matching lines @@
 class DeferredCode: public ZoneObject {
  public:
   explicit DeferredCode(CodeGenerator* generator);
   virtual ~DeferredCode() { }
 
   virtual void Generate() = 0;
 
   MacroAssembler* masm() const { return masm_; }
   CodeGenerator* generator() const { return generator_; }
 
-  Label* enter() { return &enter_; }
-  Label* exit() { return &exit_; }
+  JumpTarget* enter() { return &enter_; }
+  JumpTarget* exit() { return &exit_; }
 
   int statement_position() const { return statement_position_; }
   int position() const { return position_; }
 
 #ifdef DEBUG
   void set_comment(const char* comment) { comment_ = comment; }
   const char* comment() const { return comment_; }
 #else
   inline void set_comment(const char* comment) { }
   const char* comment() const { return ""; }
 #endif
 
  protected:
   // The masm_ field is manipulated when compiling stubs with the
   // BEGIN_STUB and END_STUB macros. For that reason, it cannot be
   // constant.
   MacroAssembler* masm_;
 
  private:
   CodeGenerator* const generator_;
-  Label enter_;
-  Label exit_;
+  JumpTarget enter_;
+  JumpTarget exit_;
   int statement_position_;
   int position_;
 #ifdef DEBUG
   const char* comment_;
 #endif
   DISALLOW_COPY_AND_ASSIGN(DeferredCode);
 };
 
 
 // RuntimeStub models code stubs calling entry points in the Runtime class.
@@ skipping 156 matching lines @@
     PrintF("ArgumentsAccessStub (type %d)\n", type_);
   }
 #endif
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CODEGEN_H_