1 /* 2 * Copyright (C) 2017 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_CODE_SINKING_H_ 18 #define ART_COMPILER_OPTIMIZING_CODE_SINKING_H_ 19 20 #include "base/macros.h" 21 #include "nodes.h" 22 #include "optimization.h" 23 24 namespace art HIDDEN { 25 26 /** 27 * Optimization pass to move instructions into uncommon branches, 28 * when it is safe to do so. 29 */ 30 class CodeSinking : public HOptimization { 31 public: 32 CodeSinking(HGraph* graph, 33 OptimizingCompilerStats* stats, 34 const char* name = kCodeSinkingPassName) HOptimization(graph,name,stats)35 : HOptimization(graph, name, stats) {} 36 37 bool Run() override; 38 39 static constexpr const char* kCodeSinkingPassName = "code_sinking"; 40 41 private: 42 // Tries to sink code to uncommon branches. 43 void UncommonBranchSinking(); 44 // Tries to move code only used by `end_block` and all its post-dominated / dominated 45 // blocks, to these blocks. 46 void SinkCodeToUncommonBranch(HBasicBlock* end_block); 47 48 // Coalesces the Return/ReturnVoid instructions into one, if we have two or more. We do this to 49 // avoid generating the exit frame code several times. 50 void ReturnSinking(); 51 52 DISALLOW_COPY_AND_ASSIGN(CodeSinking); 53 }; 54 55 } // namespace art 56 57 #endif // ART_COMPILER_OPTIMIZING_CODE_SINKING_H_ 58