Fix for potential issue related to replacing CheckMaps with values.

src/hydrogen-instructions.cc

 // 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 671 matching lines @@
 
 void HInstruction::PrintTo(StringStream* stream) {
   PrintMnemonicTo(stream);
   PrintDataTo(stream);
   PrintRangeTo(stream);
   PrintChangesTo(stream);
   PrintTypeTo(stream);
   if (CheckFlag(HValue::kHasNoObservableSideEffects)) {
     stream->Add(" [noOSE]");
   }
+  if (CheckFlag(HValue::kIsDead)) {
+    stream->Add(" [dead]");
+  }
 }
 
 
 void HInstruction::PrintDataTo(StringStream *stream) {
   for (int i = 0; i < OperandCount(); ++i) {
     if (i > 0) stream->Add(" ");
     OperandAt(i)->PrintNameTo(stream);
   }
 }
 
@@ skipping 3706 matching lines @@
       break;
     case kExternalMemory:
       stream->Add("[external-memory]");
       break;
   }
 
   stream->Add("@%d", offset());
 }
 
 } }  // namespace v8::internal