[interpreter, debugger] support debug breaks via bytecode array copy

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 317 matching lines @@
 };
 
 
 // -----------------------------------------------------------------------------
 // Machine instruction Immediates
 
 class Immediate BASE_EMBEDDED {
  public:
   explicit Immediate(int32_t value) : value_(value) {}
   explicit Immediate(Smi* value) {
-    DCHECK(SmiValuesAre31Bits());  // Only available for 31-bit SMI.

[Michael Starzinger, 2016/02/22 09:37:49]

Why did we need to remove this check? I seem to be missing something.

[Yang, 2016/02/22 12:48:43]

As discussed offline, this constructor is only intended for x32. Reverting this
part of the change.

     value_ = static_cast<int32_t>(reinterpret_cast<intptr_t>(value));
   }
 
  private:
   int32_t value_;
 
   friend class Assembler;
 };
 
 
@@ skipping 1858 matching lines @@
   Assembler* assembler_;
 #ifdef DEBUG
   int space_before_;
 #endif
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_X64_ASSEMBLER_X64_H_