1/* 2 * Copyright (C) 2014 The Android Open Source Project 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 17#ifndef ART_COMPILER_OPTIMIZING_DEAD_CODE_ELIMINATION_H_ 18#define ART_COMPILER_OPTIMIZING_DEAD_CODE_ELIMINATION_H_ 19 20#include "nodes.h" 21#include "optimization.h" 22#include "optimizing_compiler_stats.h" 23 24namespace art { 25 26/** 27 * Optimization pass performing dead code elimination (removal of 28 * unused variables/instructions) on the SSA form. 29 */ 30class HDeadCodeElimination : public HOptimization { 31 public: 32 HDeadCodeElimination(HGraph* graph, 33 OptimizingCompilerStats* stats = nullptr, 34 const char* name = kInitialDeadCodeEliminationPassName) 35 : HOptimization(graph, true, name, stats) {} 36 37 void Run() OVERRIDE; 38 39 static constexpr const char* kInitialDeadCodeEliminationPassName = "dead_code_elimination"; 40 static constexpr const char* kFinalDeadCodeEliminationPassName = "dead_code_elimination_final"; 41 42 private: 43 void MaybeRecordDeadBlock(HBasicBlock* block); 44 void RemoveDeadBlocks(); 45 void RemoveDeadInstructions(); 46 47 DISALLOW_COPY_AND_ASSIGN(HDeadCodeElimination); 48}; 49 50} // namespace art 51 52#endif // ART_COMPILER_OPTIMIZING_DEAD_CODE_ELIMINATION_H_ 53