| // 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 { |
| namespace internal { |
| namespace compiler { |
| |
| // Forward declarations. |
| class JSGraph; |
| class JSOperatorBuilder; |
| |
| // Pair of a context and its distance from some point of reference. |
| struct OuterContext { |
| OuterContext() : context(), distance() {} |
| OuterContext(Handle<Context> context_, size_t distance_) |
| : context(context_), distance(distance_) {} |
| Handle<Context> context; |
| size_t distance; |
| }; |
| |
| // Specializes a given JSGraph to a given context, potentially constant folding |
| // some {LoadContext} nodes or strength reducing some {StoreContext} nodes. |
| // Additionally, constant-folds the function parameter if {closure} is given. |
| // |
| // The context can be the incoming function context or any outer context |
| // thereof, as indicated by {outer}'s {distance}. |
| class JSContextSpecialization final : public AdvancedReducer { |
| public: |
| JSContextSpecialization(Editor* editor, JSGraph* jsgraph, |
| Maybe<OuterContext> outer, |
| MaybeHandle<JSFunction> closure) |
| : AdvancedReducer(editor), |
| jsgraph_(jsgraph), |
| outer_(outer), |
| closure_(closure) {} |
| |
| const char* reducer_name() const override { |
| return "JSContextSpecialization"; |
| } |
| |
| Reduction Reduce(Node* node) final; |
| |
| private: |
| Reduction ReduceParameter(Node* node); |
| Reduction ReduceJSLoadContext(Node* node); |
| Reduction ReduceJSStoreContext(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; |
| JSGraph* jsgraph() const { return jsgraph_; } |
| Maybe<OuterContext> outer() const { return outer_; } |
| MaybeHandle<JSFunction> closure() const { return closure_; } |
| |
| JSGraph* const jsgraph_; |
| Maybe<OuterContext> outer_; |
| MaybeHandle<JSFunction> closure_; |
| |
| DISALLOW_COPY_AND_ASSIGN(JSContextSpecialization); |
| }; |
| |
| } // namespace compiler |
| } // namespace internal |
| } // namespace v8 |
| |
| #endif // V8_COMPILER_JS_CONTEXT_SPECIALIZATION_H_ |