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_RUNTIME_EXPERIMENTAL_FLAGS_H_ 18 #define ART_RUNTIME_EXPERIMENTAL_FLAGS_H_ 19 20 #include <ostream> 21 22 namespace art { 23 24 // Possible experimental features that might be enabled. 25 struct ExperimentalFlags { 26 // The actual flag values. 27 enum { 28 kNone = 0x0000, 29 kMethodHandles = 0x0004, // 0b00000100 30 }; 31 ExperimentalFlagsExperimentalFlags32 constexpr ExperimentalFlags() : value_(0x0000) {} ExperimentalFlagsExperimentalFlags33 constexpr ExperimentalFlags(decltype(kNone) t) // NOLINT, implicit 34 : value_(static_cast<uint32_t>(t)) {} 35 decltypeExperimentalFlags36 constexpr operator decltype(kNone)() const { 37 return static_cast<decltype(kNone)>(value_); 38 } 39 40 constexpr explicit operator bool() const { 41 return value_ != kNone; 42 } 43 44 constexpr ExperimentalFlags operator|(const decltype(kNone)& b) const { 45 return static_cast<decltype(kNone)>(value_ | static_cast<uint32_t>(b)); 46 } 47 constexpr ExperimentalFlags operator|(const ExperimentalFlags& b) const { 48 return static_cast<decltype(kNone)>(value_ | b.value_); 49 } 50 51 constexpr ExperimentalFlags operator&(const ExperimentalFlags& b) const { 52 return static_cast<decltype(kNone)>(value_ & b.value_); 53 } decltypeExperimentalFlags54 constexpr ExperimentalFlags operator&(const decltype(kNone)& b) const { 55 return static_cast<decltype(kNone)>(value_ & static_cast<uint32_t>(b)); 56 } 57 58 constexpr bool operator==(const ExperimentalFlags& b) const { 59 return value_ == b.value_; 60 } 61 62 private: 63 uint32_t value_; 64 }; 65 66 inline std::ostream& operator<<(std::ostream& stream, const ExperimentalFlags& e) { 67 bool started = false; 68 if (e & ExperimentalFlags::kMethodHandles) { 69 stream << (started ? "|" : "") << "kMethodHandles"; 70 started = true; 71 } 72 if (!started) { 73 stream << "kNone"; 74 } 75 return stream; 76 } 77 78 inline std::ostream& operator<<(std::ostream& stream, const decltype(ExperimentalFlags::kNone)& e) { 79 return stream << ExperimentalFlags(e); 80 } 81 82 } // namespace art 83 84 #endif // ART_RUNTIME_EXPERIMENTAL_FLAGS_H_ 85