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

src/frames.h

Index: src/frames.h
diff --git a/src/frames.h b/src/frames.h
index 9eee5a136e9b8d35cfa61215b7a06afb76e6e092..3a9fa2043b27562b6a8f5476efee68f7b0d4367c 100644
--- a/src/frames.h
+++ b/src/frames.h
@@ -466,6 +466,10 @@ class StandardFrame: public StackFrame {
     return static_cast<StandardFrame*>(frame);
   }
 
+  // Architecture-specific register description.
+  static Register sp_register();
+  static Register fp_register();
+
  protected:
   inline explicit StandardFrame(StackFrameIteratorBase* iterator);
 
@@ -602,7 +606,6 @@ class JavaScriptFrame: public StandardFrame {
       int* stack_slots, HandlerTable::CatchPrediction* prediction);
 
   // Architecture-specific register description.
-  static Register fp_register();
   static Register context_register();
   static Register constant_pool_pointer_register();