Revert "Made test.py not mention the defunct --crankshaft flag."

src/x64/assembler-x64.h

 // Copyright (c) 1994-2006 Sun Microsystems 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.
 //
@@ skipping 1571 matching lines @@
   byte* buffer_;
   int buffer_size_;
   // True if the assembler owns the buffer, false if buffer is external.
   bool own_buffer_;
 
   // code generation
   byte* pc_;  // the program counter; moves forward
   RelocInfoWriter reloc_info_writer;
 
   List< Handle<Code> > code_targets_;
+  // push-pop elimination
+  byte* last_pc_;
 
   PositionsRecorder positions_recorder_;
 
   bool emit_debug_code_;
 
   friend class PositionsRecorder;
 };
 
 
 // Helper class that ensures that there is enough space for generating
@@ skipping 19 matching lines @@
  private:
   Assembler* assembler_;
 #ifdef DEBUG
   int space_before_;
 #endif
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_ASSEMBLER_X64_H_