1 /* 2 * Copyright (C) 2015 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_NODES_ARM_H_ 18 #define ART_COMPILER_OPTIMIZING_NODES_ARM_H_ 19 20 namespace art { 21 22 class HArmDexCacheArraysBase FINAL : public HExpression<0> { 23 public: HArmDexCacheArraysBase(const DexFile & dex_file)24 explicit HArmDexCacheArraysBase(const DexFile& dex_file) 25 : HExpression(Primitive::kPrimInt, SideEffects::None(), kNoDexPc), 26 dex_file_(&dex_file), 27 element_offset_(static_cast<size_t>(-1)) { } 28 CanBeMoved()29 bool CanBeMoved() const OVERRIDE { return true; } 30 UpdateElementOffset(size_t element_offset)31 void UpdateElementOffset(size_t element_offset) { 32 // Use the lowest offset from the requested elements so that all offsets from 33 // this base are non-negative because our assemblers emit negative-offset loads 34 // as a sequence of two or more instructions. (However, positive offsets beyond 35 // 4KiB also require two or more instructions, so this simple heuristic could 36 // be improved for cases where there is a dense cluster of elements far from 37 // the lowest offset. This is expected to be rare enough though, so we choose 38 // not to spend compile time on elaborate calculations.) 39 element_offset_ = std::min(element_offset_, element_offset); 40 } 41 GetDexFile()42 const DexFile& GetDexFile() const { 43 return *dex_file_; 44 } 45 GetElementOffset()46 size_t GetElementOffset() const { 47 return element_offset_; 48 } 49 50 DECLARE_INSTRUCTION(ArmDexCacheArraysBase); 51 52 private: 53 const DexFile* dex_file_; 54 size_t element_offset_; 55 56 DISALLOW_COPY_AND_ASSIGN(HArmDexCacheArraysBase); 57 }; 58 59 } // namespace art 60 61 #endif // ART_COMPILER_OPTIMIZING_NODES_ARM_H_ 62