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_ARCH_CODE_OFFSET_H_ 18 #define ART_RUNTIME_ARCH_CODE_OFFSET_H_ 19 20 #include <iosfwd> 21 22 #include "base/bit_utils.h" 23 #include "base/logging.h" 24 #include "instruction_set.h" 25 26 namespace art { 27 28 // CodeOffset is a holder for compressed code offsets. Since some architectures have alignment 29 // requirements it is possible to compress code offsets to reduce stack map sizes. 30 class CodeOffset { 31 public: 32 ALWAYS_INLINE static CodeOffset FromOffset(uint32_t offset, InstructionSet isa = kRuntimeISA) { 33 return CodeOffset(offset / GetInstructionSetInstructionAlignment(isa)); 34 } 35 FromCompressedOffset(uint32_t offset)36 ALWAYS_INLINE static CodeOffset FromCompressedOffset(uint32_t offset) { 37 return CodeOffset(offset); 38 } 39 40 ALWAYS_INLINE uint32_t Uint32Value(InstructionSet isa = kRuntimeISA) const { 41 uint32_t decoded = value_ * GetInstructionSetInstructionAlignment(isa); 42 DCHECK_GE(decoded, value_) << "Integer overflow"; 43 return decoded; 44 } 45 46 // Return compressed internal value. CompressedValue()47 ALWAYS_INLINE uint32_t CompressedValue() const { 48 return value_; 49 } 50 51 ALWAYS_INLINE CodeOffset() = default; 52 ALWAYS_INLINE CodeOffset(const CodeOffset&) = default; 53 ALWAYS_INLINE CodeOffset& operator=(const CodeOffset&) = default; 54 ALWAYS_INLINE CodeOffset& operator=(CodeOffset&&) = default; 55 56 private: CodeOffset(uint32_t value)57 ALWAYS_INLINE explicit CodeOffset(uint32_t value) : value_(value) {} 58 59 uint32_t value_ = 0u; 60 }; 61 62 inline bool operator==(const CodeOffset& a, const CodeOffset& b) { 63 return a.CompressedValue() == b.CompressedValue(); 64 } 65 66 inline bool operator!=(const CodeOffset& a, const CodeOffset& b) { 67 return !(a == b); 68 } 69 70 inline bool operator<(const CodeOffset& a, const CodeOffset& b) { 71 return a.CompressedValue() < b.CompressedValue(); 72 } 73 74 inline bool operator<=(const CodeOffset& a, const CodeOffset& b) { 75 return a.CompressedValue() <= b.CompressedValue(); 76 } 77 78 inline bool operator>(const CodeOffset& a, const CodeOffset& b) { 79 return a.CompressedValue() > b.CompressedValue(); 80 } 81 82 inline bool operator>=(const CodeOffset& a, const CodeOffset& b) { 83 return a.CompressedValue() >= b.CompressedValue(); 84 } 85 86 inline std::ostream& operator<<(std::ostream& os, const CodeOffset& offset) { 87 return os << offset.Uint32Value(); 88 } 89 90 } // namespace art 91 92 #endif // ART_RUNTIME_ARCH_CODE_OFFSET_H_ 93