1 // Copyright (c) 2018 Google LLC 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #ifndef SOURCE_REDUCE_REDUCTION_PASS_H_ 16 #define SOURCE_REDUCE_REDUCTION_PASS_H_ 17 18 #include <limits> 19 20 #include "source/opt/ir_context.h" 21 #include "source/reduce/reduction_opportunity_finder.h" 22 #include "spirv-tools/libspirv.hpp" 23 24 namespace spvtools { 25 namespace reduce { 26 27 // Abstract class representing a reduction pass, which can be repeatedly 28 // invoked to find and apply particular reduction opportunities to a SPIR-V 29 // binary. In the spirit of delta debugging, a pass initially tries to apply 30 // large chunks of reduction opportunities, iterating through available 31 // opportunities at a given granularity. When an iteration over available 32 // opportunities completes, the granularity is reduced and iteration starts 33 // again, until the minimum granularity is reached. 34 class ReductionPass { 35 public: 36 // Constructs a reduction pass with a given target environment, |target_env|, 37 // and a given finder of reduction opportunities, |finder|. ReductionPass(const spv_target_env target_env,std::unique_ptr<ReductionOpportunityFinder> finder)38 explicit ReductionPass(const spv_target_env target_env, 39 std::unique_ptr<ReductionOpportunityFinder> finder) 40 : target_env_(target_env), 41 finder_(std::move(finder)), 42 index_(0), 43 granularity_(std::numeric_limits<uint32_t>::max()) {} 44 45 // Applies the reduction pass to the given binary by applying a "chunk" of 46 // reduction opportunities. Returns the new binary if a chunk was applied; in 47 // this case, before the next call the caller must invoke 48 // NotifyInteresting(...) to indicate whether the new binary is interesting. 49 // Returns an empty vector if there are no more chunks left to apply; in this 50 // case, the index will be reset and the granularity lowered for the next 51 // round. 52 std::vector<uint32_t> TryApplyReduction(const std::vector<uint32_t>& binary); 53 54 // Notifies the reduction pass whether the binary returned from 55 // TryApplyReduction is interesting, so that the next call to 56 // TryApplyReduction will avoid applying the same chunk of opportunities. 57 void NotifyInteresting(bool interesting); 58 59 // Sets a consumer to which relevant messages will be directed. 60 void SetMessageConsumer(MessageConsumer consumer); 61 62 // Returns true if the granularity with which reduction opportunities are 63 // applied has reached a minimum. 64 bool ReachedMinimumGranularity() const; 65 66 // Returns the name associated with this reduction pass (based on its 67 // associated finder). 68 std::string GetName() const; 69 70 private: 71 const spv_target_env target_env_; 72 const std::unique_ptr<ReductionOpportunityFinder> finder_; 73 MessageConsumer consumer_; 74 uint32_t index_; 75 uint32_t granularity_; 76 }; 77 78 } // namespace reduce 79 } // namespace spvtools 80 81 #endif // SOURCE_REDUCE_REDUCTION_PASS_H_ 82