Improve our simple elimination of hole checks.

src/x64/lithium-x64.cc

 // Copyright 2011 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 1704 matching lines @@
     return DefineAsRegister(new LConstantT);
   } else {
     UNREACHABLE();
     return NULL;
   }
 }
 
 
 LInstruction* LChunkBuilder::DoLoadGlobalCell(HLoadGlobalCell* instr) {
   LLoadGlobalCell* result = new LLoadGlobalCell;
-  return instr->check_hole_value()
+  return instr->RequiresHoleCheck()
       ? AssignEnvironment(DefineAsRegister(result))
       : DefineAsRegister(result);
 }
 
 
 LInstruction* LChunkBuilder::DoLoadGlobalGeneric(HLoadGlobalGeneric* instr) {
   LOperand* global_object = UseFixed(instr->global_object(), rax);
   LLoadGlobalGeneric* result = new LLoadGlobalGeneric(global_object);
   return MarkAsCall(DefineFixed(result, rax), instr);
 }
 
 
 LInstruction* LChunkBuilder::DoStoreGlobalCell(HStoreGlobalCell* instr) {
   LStoreGlobalCell* result =
       new LStoreGlobalCell(UseTempRegister(instr->value()),
                            TempRegister(),
                            TempRegister());
-  return instr->check_hole_value() ? AssignEnvironment(result) : result;
+  return instr->RequiresHoleCheck() ? AssignEnvironment(result) : result;
 }
 
 
 LInstruction* LChunkBuilder::DoStoreGlobalGeneric(HStoreGlobalGeneric* instr) {
   LOperand* global_object = UseFixed(instr->global_object(), rdx);
   LOperand* value = UseFixed(instr->value(), rax);
   LStoreGlobalGeneric* result =  new LStoreGlobalGeneric(global_object, value);
   return MarkAsCall(result, instr);
 }
 
@@ skipping 423 matching lines @@
   LOperand* key = UseOrConstantAtStart(instr->key());
   LOperand* object = UseOrConstantAtStart(instr->object());
   LIn* result = new LIn(key, object);
   return MarkAsCall(DefineFixed(result, rax), instr);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64