Don't emit code for instructions that are hiding behind an HSoftDeoptimize

src/x64/lithium-x64.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 668 matching lines @@
   ASSERT(operand->HasFixedPolicy());
   return operand;
 }
 
 
 LInstruction* LChunkBuilder::DoBlockEntry(HBlockEntry* instr) {
   return new(zone()) LLabel(instr->block());
 }
 
 
+LInstruction* LChunkBuilder::DoDummyUse(HDummyUse* instr) {
+  return DefineAsRegister(new(zone()) LDummyUse(UseAny(instr->value())));
+}
+
+
 LInstruction* LChunkBuilder::DoSoftDeoptimize(HSoftDeoptimize* instr) {
   return AssignEnvironment(new(zone()) LDeoptimize);
 }
 
 
 LInstruction* LChunkBuilder::DoDeoptimize(HDeoptimize* instr) {
   return AssignEnvironment(new(zone()) LDeoptimize);
 }
 
 
@@ skipping 1621 matching lines @@
 LInstruction* LChunkBuilder::DoLoadFieldByIndex(HLoadFieldByIndex* instr) {
   LOperand* object = UseRegister(instr->object());
   LOperand* index = UseTempRegister(instr->index());
   return DefineSameAsFirst(new(zone()) LLoadFieldByIndex(object, index));
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64