Merge virtual frames by copying registers to registers....

src/virtual-frame-ia32.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 425 matching lines @@
   // Sync the range of elements in [begin, end).
   void SyncRange(int begin, int end);
 
   // Store the value on top of the frame to a frame slot (typically a local
   // or parameter).
   void StoreToFrameSlotAt(int index);
 
   // Spill the topmost elements of the frame to memory (eg, they are the
   // arguments to a call) and all registers.
   void PrepareForCall(int count);
+
+  // Make the register-to-register moves necessary to
+  // merge this frame with the expected frame.
+  // Register to memory moves must already have been made,
+  // and memory to register moves must follow this call.
+  // This is because some new memory-to-register moves are
+  // created in order to break cycles of register moves.
+  // Used in the implementation of MergeTo().
+  void MergeMoveRegistersToRegisters(VirtualFrame *expected);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_VIRTUAL_FRAME_IA32_H_