Re-land r8140: Deoptimize on never-executed code-paths.

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 785 matching lines @@
   allocator_->RecordTemporary(operand);
   return operand;
 }
 
 
 LInstruction* LChunkBuilder::DoBlockEntry(HBlockEntry* instr) {
   return new LLabel(instr->block());
 }
 
 
+LInstruction* LChunkBuilder::DoSoftDeoptimize(HSoftDeoptimize* instr) {
+  return AssignEnvironment(new LDeoptimize);
+}
+
+
 LInstruction* LChunkBuilder::DoDeoptimize(HDeoptimize* instr) {
   return AssignEnvironment(new LDeoptimize);
 }
 
 
 LInstruction* LChunkBuilder::DoBit(Token::Value op,
                                    HBitwiseBinaryOperation* instr) {
   if (instr->representation().IsInteger32()) {
     ASSERT(instr->left()->representation().IsInteger32());
     ASSERT(instr->right()->representation().IsInteger32());
@@ skipping 1413 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