SPIRV-Tools/source/opt/eliminate_dead_output_stores_pass.h
2023-03-28 12:40:30 -04:00

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2.7 KiB
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// Copyright (c) 2022 The Khronos Group Inc.
// Copyright (c) 2022 LunarG 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_OPT_ELIMINATE_DEAD_OUTPUT_STORES_H_
#define SOURCE_OPT_ELIMINATE_DEAD_OUTPUT_STORES_H_
#include <unordered_set>
#include "source/opt/ir_context.h"
#include "source/opt/module.h"
#include "source/opt/pass.h"
namespace spvtools {
namespace opt {
// See optimizer.hpp for documentation.
class EliminateDeadOutputStoresPass : public Pass {
public:
explicit EliminateDeadOutputStoresPass(
std::unordered_set<uint32_t>* live_locs,
std::unordered_set<uint32_t>* live_builtins)
: live_locs_(live_locs), live_builtins_(live_builtins) {}
const char* name() const override { return "eliminate-dead-output-stores"; }
Status Process() override;
// Return the mask of preserved Analyses.
IRContext::Analysis GetPreservedAnalyses() override {
return IRContext::kAnalysisDefUse |
IRContext::kAnalysisInstrToBlockMapping |
IRContext::kAnalysisCombinators | IRContext::kAnalysisCFG |
IRContext::kAnalysisDominatorAnalysis |
IRContext::kAnalysisLoopAnalysis | IRContext::kAnalysisNameMap |
IRContext::kAnalysisConstants | IRContext::kAnalysisTypes;
}
private:
// Initialize elimination
void InitializeElimination();
// Do dead output store analysis
Status DoDeadOutputStoreElimination();
// Kill all stores resulting from |ref|.
void KillAllStoresOfRef(Instruction* ref);
// Kill all dead stores resulting from |user| of loc-based |var|.
void KillAllDeadStoresOfLocRef(Instruction* user, Instruction* var);
// Kill all dead stores resulting from |user| of builtin |var|.
void KillAllDeadStoresOfBuiltinRef(Instruction* user, Instruction* var);
// Return true if any of |count| locations starting at location |start| are
// live.
bool AnyLocsAreLive(uint32_t start, uint32_t count);
// Return true if builtin |bi| is live.
bool IsLiveBuiltin(uint32_t bi);
std::unordered_set<uint32_t>* live_locs_;
std::unordered_set<uint32_t>* live_builtins_;
std::vector<Instruction*> kill_list_;
};
} // namespace opt
} // namespace spvtools
#endif // SOURCE_OPT_ELIMINATE_DEAD_OUTPUT_STORES_H_