[turbofan] Avoid unnecessary write barriers and improve code generation.

src/compiler/code-generator-impl.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_COMPILER_CODE_GENERATOR_IMPL_H_
 #define V8_COMPILER_CODE_GENERATOR_IMPL_H_
 
 #include "src/code-stubs.h"
 #include "src/compiler/code-generator.h"
 #include "src/compiler/instruction.h"
@@ skipping 129 matching lines @@
 // Generator for out-of-line code that is emitted after the main code is done.
 class OutOfLineCode : public ZoneObject {
  public:
   explicit OutOfLineCode(CodeGenerator* gen);
   virtual ~OutOfLineCode();
 
   virtual void Generate() = 0;
 
   Label* entry() { return &entry_; }
   Label* exit() { return &exit_; }
+  Frame* frame() const { return frame_; }
+  Isolate* isolate() const { return masm()->isolate(); }
   MacroAssembler* masm() const { return masm_; }
   OutOfLineCode* next() const { return next_; }
 
  private:
   Label entry_;
   Label exit_;
+  Frame* const frame_;
   MacroAssembler* const masm_;
   OutOfLineCode* const next_;
 };
 
 
 // TODO(dcarney): generify this on bleeding_edge and replace this call
 // when merged.
 static inline void FinishCode(MacroAssembler* masm) {
 #if V8_TARGET_ARCH_ARM64 || V8_TARGET_ARCH_ARM
   masm->CheckConstPool(true, false);
 #elif V8_TARGET_ARCH_IA32 || V8_TARGET_ARCH_X64
   masm->ud2();
 #endif
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_CODE_GENERATOR_IMPL_H