factor out "ReloadContextFromFrame"

src/x64/macro-assembler-x64.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 1127 matching lines @@
   // Generates code for reporting that an illegal operation has
   // occurred.
   void IllegalOperation(int num_arguments);
 
   // Picks out an array index from the hash field.
   // Register use:
   //   hash - holds the index's hash. Clobbered.
   //   index - holds the overwritten index on exit.
   void IndexFromHash(Register hash, Register index);
 
+  // Reload the context register from a standard stack frame.
+  void ReloadContextFromFrame();
+
   // Find the function context up the context chain.
   void LoadContext(Register dst, int context_chain_length);
 
   // Conditionally load the cached Array transitioned map of type
   // transitioned_kind from the native context if the map in register
   // map_in_out is the cached Array map in the native context of
   // expected_kind.
   void LoadTransitionedArrayMapConditional(
       ElementsKind expected_kind,
       ElementsKind transitioned_kind,
@@ skipping 352 matching lines @@
     masm->popfq();                                                           \
   }                                                                          \
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_MACRO_ASSEMBLER_X64_H_