Capture register clearing on loop iteration

src/regexp-macro-assembler.h

 // Copyright 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 149 matching lines @@
   // will go to this label. Always checks the backtrack stack limit.
   virtual void PushBacktrack(Label* label) = 0;
   virtual void PushCurrentPosition() = 0;
   virtual void PushRegister(int register_index,
                             StackCheckFlag check_stack_limit) = 0;
   virtual void ReadCurrentPositionFromRegister(int reg) = 0;
   virtual void ReadStackPointerFromRegister(int reg) = 0;
   virtual void SetRegister(int register_index, int to) = 0;
   virtual void Succeed() = 0;
   virtual void WriteCurrentPositionToRegister(int reg, int cp_offset) = 0;
+  virtual void ClearRegister(int reg) = 0;
   virtual void WriteStackPointerToRegister(int reg) = 0;
 
  private:
 };
 
 
 struct ArraySlice {
  public:
   ArraySlice(Handle<ByteArray> array, size_t offset)
     : array_(array), offset_(offset) {}
@@ skipping 29 matching lines @@
   ArraySlice GetBuffer(Vector<T> values);
  private:
   size_t byte_array_size_;
   Handle<ByteArray> current_byte_array_;
   int current_byte_array_free_offset_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_REGEXP_MACRO_ASSEMBLER_H_