1 // Copyright (c) 2022 The Khronos Group Inc. 2 // Copyright (c) 2022 LunarG Inc. 3 // 4 // Licensed under the Apache License, Version 2.0 (the "License"); 5 // you may not use this file except in compliance with the License. 6 // You may obtain a copy of the License at 7 // 8 // http://www.apache.org/licenses/LICENSE-2.0 9 // 10 // Unless required by applicable law or agreed to in writing, software 11 // distributed under the License is distributed on an "AS IS" BASIS, 12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 // See the License for the specific language governing permissions and 14 // limitations under the License. 15 16 #ifndef SOURCE_OPT_ELIMINATE_DEAD_INPUT_COMPONENTS_H_ 17 #define SOURCE_OPT_ELIMINATE_DEAD_INPUT_COMPONENTS_H_ 18 19 #include <unordered_map> 20 21 #include "source/opt/ir_context.h" 22 #include "source/opt/module.h" 23 #include "source/opt/pass.h" 24 25 namespace spvtools { 26 namespace opt { 27 28 // See optimizer.hpp for documentation. 29 class EliminateDeadIOComponentsPass : public Pass { 30 public: 31 explicit EliminateDeadIOComponentsPass(spv::StorageClass elim_sclass, 32 bool safe_mode = true) elim_sclass_(elim_sclass)33 : elim_sclass_(elim_sclass), safe_mode_(safe_mode) {} 34 name()35 const char* name() const override { 36 return "eliminate-dead-input-components"; 37 } 38 Status Process() override; 39 40 // Return the mask of preserved Analyses. GetPreservedAnalyses()41 IRContext::Analysis GetPreservedAnalyses() override { 42 return IRContext::kAnalysisDefUse | 43 IRContext::kAnalysisInstrToBlockMapping | 44 IRContext::kAnalysisCombinators | IRContext::kAnalysisCFG | 45 IRContext::kAnalysisDominatorAnalysis | 46 IRContext::kAnalysisLoopAnalysis | IRContext::kAnalysisNameMap | 47 IRContext::kAnalysisConstants | IRContext::kAnalysisTypes; 48 } 49 50 private: 51 // Find the max constant used to index the variable declared by |var| 52 // through OpAccessChain or OpInBoundsAccessChain. If any non-constant 53 // indices or non-Op*AccessChain use of |var|, return |original_max|. 54 unsigned FindMaxIndex(const Instruction& var, const unsigned original_max, 55 const bool skip_first_index = false); 56 57 // Change the length of the array |inst| to |length| 58 void ChangeArrayLength(Instruction& inst, unsigned length); 59 60 // Change the length of the struct in |io_var| to |length|. |io_var| 61 // is either the struct or a per-vertex-array of the struct. 62 void ChangeIOVarStructLength(Instruction& io_var, unsigned length); 63 64 // Storage class to be optimized. Must be Input or Output. 65 spv::StorageClass elim_sclass_; 66 67 // Only make changes that will not cause interface incompatibility if done 68 // standalone. Currently this is only Input variables in vertex shaders. 69 bool safe_mode_; 70 }; 71 72 } // namespace opt 73 } // namespace spvtools 74 75 #endif // SOURCE_OPT_ELIMINATE_DEAD_INPUT_COMPONENTS_H_ 76