1 // Copyright 2017 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef V8_COMPILER_JS_TYPE_HINT_LOWERING_H_ 6 #define V8_COMPILER_JS_TYPE_HINT_LOWERING_H_ 7 8 #include "src/compiler/graph-reducer.h" 9 #include "src/handles.h" 10 11 namespace v8 { 12 namespace internal { 13 namespace compiler { 14 15 // Forward declarations. 16 class JSGraph; 17 18 // The type-hint lowering consumes feedback about data operations (i.e. unary 19 // and binary operations) to emit nodes using speculative simplified operators 20 // in favor of the generic JavaScript operators. 21 // 22 // This lowering is implemented as an early reduction and can be applied before 23 // nodes are placed into the initial graph. It provides the ability to shortcut 24 // the JavaScript-level operators and directly emit simplified-level operators 25 // even during initial graph building. This is the reason this lowering doesn't 26 // follow the interface of the reducer framework used after graph construction. 27 class JSTypeHintLowering { 28 public: 29 JSTypeHintLowering(JSGraph* jsgraph, Handle<FeedbackVector> feedback_vector); 30 31 // Potential reduction of binary (arithmetic, logical and shift) operations. 32 Reduction ReduceBinaryOperation(const Operator* op, Node* left, Node* right, 33 Node* effect, Node* control, 34 FeedbackSlot slot); 35 36 private: 37 friend class JSSpeculativeBinopBuilder; 38 jsgraph()39 JSGraph* jsgraph() const { return jsgraph_; } feedback_vector()40 const Handle<FeedbackVector>& feedback_vector() const { 41 return feedback_vector_; 42 } 43 44 JSGraph* jsgraph_; 45 Handle<FeedbackVector> feedback_vector_; 46 47 DISALLOW_COPY_AND_ASSIGN(JSTypeHintLowering); 48 }; 49 50 } // namespace compiler 51 } // namespace internal 52 } // namespace v8 53 54 #endif // V8_COMPILER_JS_TYPE_HINT_LOWERING_H_ 55