[turbofan]: Elide extra move when accessing stack or frame register

src/interface-descriptors.h

 // Copyright 2014 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_CALL_INTERFACE_DESCRIPTOR_H_
 #define V8_CALL_INTERFACE_DESCRIPTOR_H_
 
 #include "src/assembler.h"
 #include "src/macro-assembler.h"
 
@@ skipping 151 matching lines @@
 
   // Some platforms have extra information to associate with the descriptor.
   PlatformInterfaceDescriptor* platform_specific_descriptor() const {
     return data()->platform_specific_descriptor();
   }
 
   Type::FunctionType* GetFunctionType() const {
     return data()->function_type();
   }
 
-  static const Register ContextRegister();
-
   const char* DebugName(Isolate* isolate) const;
 
   static Type::FunctionType* BuildDefaultFunctionType(Isolate* isolate,
                                                       int paramater_count);
 
  protected:
   const CallInterfaceDescriptorData* data() const { return data_; }
 
   virtual Type::FunctionType* BuildCallInterfaceDescriptorFunctionType(
       Isolate* isolate, int register_param_count) {
@@ skipping 471 matching lines @@
 }  // namespace v8::internal
 
 
 #if V8_TARGET_ARCH_ARM64
 #include "src/arm64/interface-descriptors-arm64.h"
 #elif V8_TARGET_ARCH_ARM
 #include "src/arm/interface-descriptors-arm.h"
 #endif
 
 #endif  // V8_CALL_INTERFACE_DESCRIPTOR_H_