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_RUNTIME_METHOD_INFO_H_ 18 #define ART_RUNTIME_METHOD_INFO_H_ 19 20 #include "base/logging.h" 21 #include "leb128.h" 22 #include "memory_region.h" 23 24 namespace art { 25 26 // Method info is for not dedupe friendly data of a method. Currently it only holds methods indices. 27 // Putting this data in MethodInfo instead of code infos saves ~5% oat size. 28 class MethodInfo { 29 using MethodIndexType = uint16_t; 30 31 public: 32 // Reading mode MethodInfo(const uint8_t * ptr)33 explicit MethodInfo(const uint8_t* ptr) { 34 if (ptr != nullptr) { 35 num_method_indices_ = DecodeUnsignedLeb128(&ptr); 36 region_ = MemoryRegion(const_cast<uint8_t*>(ptr), 37 num_method_indices_ * sizeof(MethodIndexType)); 38 } 39 } 40 41 // Writing mode MethodInfo(uint8_t * ptr,size_t num_method_indices)42 MethodInfo(uint8_t* ptr, size_t num_method_indices) : num_method_indices_(num_method_indices) { 43 DCHECK(ptr != nullptr); 44 ptr = EncodeUnsignedLeb128(ptr, num_method_indices_); 45 region_ = MemoryRegion(ptr, num_method_indices_ * sizeof(MethodIndexType)); 46 } 47 ComputeSize(size_t num_method_indices)48 static size_t ComputeSize(size_t num_method_indices) { 49 uint8_t temp[8]; 50 uint8_t* ptr = temp; 51 ptr = EncodeUnsignedLeb128(ptr, num_method_indices); 52 return (ptr - temp) + num_method_indices * sizeof(MethodIndexType); 53 } 54 GetMethodIndex(size_t index)55 ALWAYS_INLINE MethodIndexType GetMethodIndex(size_t index) const { 56 // Use bit functions to avoid pesky alignment requirements. 57 return region_.LoadBits(index * BitSizeOf<MethodIndexType>(), BitSizeOf<MethodIndexType>()); 58 } 59 SetMethodIndex(size_t index,MethodIndexType method_index)60 void SetMethodIndex(size_t index, MethodIndexType method_index) { 61 region_.StoreBits(index * BitSizeOf<MethodIndexType>(), 62 method_index, 63 BitSizeOf<MethodIndexType>()); 64 } 65 NumMethodIndices()66 size_t NumMethodIndices() const { 67 return num_method_indices_; 68 } 69 70 private: 71 size_t num_method_indices_ = 0u; 72 MemoryRegion region_; 73 }; 74 75 } // namespace art 76 77 #endif // ART_RUNTIME_METHOD_INFO_H_ 78