| // Copyright (c) 2018 Google Inc. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #ifndef SOURCE_REDUCE_OPERAND_TO_DOMINATING_ID_REDUCTION_OPPORTUNITY_FINDER_H_ |
| #define SOURCE_REDUCE_OPERAND_TO_DOMINATING_ID_REDUCTION_OPPORTUNITY_FINDER_H_ |
| |
| #include "source/reduce/reduction_opportunity_finder.h" |
| |
| namespace spvtools { |
| namespace reduce { |
| |
| // A finder that aims to bring to SPIR-V (and generalize) the idea from |
| // human-readable languages of e.g. finding opportunities to replace an |
| // expression with one of its arguments, (x + y) -> x, or with a reference to an |
| // identifier that was assigned to higher up in the program. The generalization |
| // of this is to replace an id with a different id of the same type defined in |
| // some dominating instruction. |
| // |
| // If id x is defined and then used several times, changing each use of x to |
| // some dominating definition may eventually allow the statement defining x |
| // to be eliminated by another pass. |
| class OperandToDominatingIdReductionOpportunityFinder |
| : public ReductionOpportunityFinder { |
| public: |
| OperandToDominatingIdReductionOpportunityFinder() = default; |
| |
| ~OperandToDominatingIdReductionOpportunityFinder() override = default; |
| |
| std::string GetName() const final; |
| |
| std::vector<std::unique_ptr<ReductionOpportunity>> GetAvailableOpportunities( |
| opt::IRContext* context, uint32_t target_function) const final; |
| |
| private: |
| void GetOpportunitiesForDominatingInst( |
| std::vector<std::unique_ptr<ReductionOpportunity>>* opportunities, |
| opt::Instruction* dominating_instruction, |
| opt::Function::iterator candidate_dominator_block, |
| opt::Function* function, opt::IRContext* context) const; |
| }; |
| |
| } // namespace reduce |
| } // namespace spvtools |
| |
| #endif // SOURCE_REDUCE_OPERAND_TO_DOMINATING_ID_REDUCTION_OPPORTUNITY_FINDER_H_ |