[compiler] Generalize JSContextSpecialization.

src/compiler/js-context-specialization.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_COMPILER_JS_CONTEXT_SPECIALIZATION_H_
 #define V8_COMPILER_JS_CONTEXT_SPECIALIZATION_H_
 
 #include "src/compiler/graph-reducer.h"
 
 namespace v8 {
@@ skipping 12 matching lines @@
   JSContextSpecialization(Editor* editor, JSGraph* jsgraph,
                           MaybeHandle<Context> context)
       : AdvancedReducer(editor), jsgraph_(jsgraph), context_(context) {}
 
   Reduction Reduce(Node* node) final;
 
  private:
   Reduction ReduceJSLoadContext(Node* node);
   Reduction ReduceJSStoreContext(Node* node);
 
-  // Returns the {Context} to specialize {node} to (if any).
-  MaybeHandle<Context> GetSpecializationContext(Node* node);
+  Reduction SimplifyJSStoreContext(Node* node, Node* new_context,
+                                   size_t new_depth);
+  Reduction SimplifyJSLoadContext(Node* node, Node* new_context,
+                                  size_t new_depth);
 
   Isolate* isolate() const;
   JSOperatorBuilder* javascript() const;
   JSGraph* jsgraph() const { return jsgraph_; }
   MaybeHandle<Context> context() const { return context_; }
 
   JSGraph* const jsgraph_;
   MaybeHandle<Context> context_;
 
   DISALLOW_COPY_AND_ASSIGN(JSContextSpecialization);
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_JS_CONTEXT_SPECIALIZATION_H_