// Copyright 2016 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_REDUNDANCY_ELIMINATION_H_ #define V8_COMPILER_REDUNDANCY_ELIMINATION_H_ #include "src/compiler/graph-reducer.h" namespace v8 { namespace internal { namespace compiler { class V8_EXPORT_PRIVATE RedundancyElimination final : public AdvancedReducer { public: RedundancyElimination(Editor* editor, Zone* zone); ~RedundancyElimination() final; const char* reducer_name() const override { return "RedundancyElimination"; } Reduction Reduce(Node* node) final; private: struct Check { Check(Node* node, Check* next) : node(node), next(next) {} Node* node; Check* next; }; class EffectPathChecks final { public: static EffectPathChecks* Copy(Zone* zone, EffectPathChecks const* checks); static EffectPathChecks const* Empty(Zone* zone); bool Equals(EffectPathChecks const* that) const; void Merge(EffectPathChecks const* that); EffectPathChecks const* AddCheck(Zone* zone, Node* node) const; Node* LookupCheck(Node* node) const; Node* LookupBoundsCheckFor(Node* node) const; private: friend Zone; EffectPathChecks(Check* head, size_t size) : head_(head), size_(size) {} // We keep track of the list length so that we can find the longest // common tail easily. Check* head_; size_t size_; }; class PathChecksForEffectNodes final { public: explicit PathChecksForEffectNodes(Zone* zone) : info_for_node_(zone) {} EffectPathChecks const* Get(Node* node) const; void Set(Node* node, EffectPathChecks const* checks); private: ZoneVector<EffectPathChecks const*> info_for_node_; }; Reduction ReduceCheckNode(Node* node); Reduction ReduceEffectPhi(Node* node); Reduction ReduceSpeculativeNumberComparison(Node* node); Reduction ReduceSpeculativeNumberOperation(Node* node); Reduction ReduceStart(Node* node); Reduction ReduceOtherNode(Node* node); Reduction TakeChecksFromFirstEffect(Node* node); Reduction UpdateChecks(Node* node, EffectPathChecks const* checks); Zone* zone() const { return zone_; } PathChecksForEffectNodes node_checks_; Zone* const zone_; DISALLOW_COPY_AND_ASSIGN(RedundancyElimination); }; } // namespace compiler } // namespace internal } // namespace v8 #endif // V8_COMPILER_REDUNDANCY_ELIMINATION_H_