Cpu-Features-vixl.cpp (5575B)
1 // Copyright 2018, VIXL authors 2 // All rights reserved. 3 // 4 // Redistribution and use in source and binary forms, with or without 5 // modification, are permitted provided that the following conditions are met: 6 // 7 // * Redistributions of source code must retain the above copyright notice, 8 // this list of conditions and the following disclaimer. 9 // * Redistributions in binary form must reproduce the above copyright notice, 10 // this list of conditions and the following disclaimer in the documentation 11 // and/or other materials provided with the distribution. 12 // * Neither the name of ARM Limited nor the names of its contributors may be 13 // used to endorse or promote products derived from this software without 14 // specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND 17 // ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 18 // WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 19 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE 20 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 22 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 23 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 27 28 #include "jit/arm64/vixl/Cpu-Features-vixl.h" 29 30 #include <ostream> 31 32 #include "jit/arm64/vixl/Cpu-vixl.h" 33 #include "jit/arm64/vixl/Globals-vixl.h" 34 #include "jit/arm64/vixl/Utils-vixl.h" 35 36 // Mozilla change: Don't use VIXL_USE_AARCH64_CPU_HELPERS for the simulator, so 37 // that we get consistent simulator behavior across architectures. 38 #if defined(__aarch64__) && !defined(JS_SIMULATOR_ARM64) 39 #define VIXL_USE_AARCH64_CPU_HELPERS 40 #endif 41 42 namespace vixl { 43 44 CPUFeatures CPUFeatures::All() { 45 CPUFeatures all; 46 all.features_.set(); 47 return all; 48 } 49 50 CPUFeatures CPUFeatures::InferFromIDRegisters() { 51 // This function assumes that kIDRegisterEmulation is available. 52 CPUFeatures features(CPUFeatures::kIDRegisterEmulation); 53 #ifdef VIXL_USE_AARCH64_CPU_HELPERS 54 // Note that the Linux kernel filters these values during emulation, so the 55 // results may not exactly match the expected hardware support. 56 features.Combine(CPU::InferCPUFeaturesFromIDRegisters()); 57 #endif 58 return features; 59 } 60 61 CPUFeatures CPUFeatures::InferFromOS(QueryIDRegistersOption option) { 62 #ifdef VIXL_USE_AARCH64_CPU_HELPERS 63 return CPU::InferCPUFeaturesFromOS(option); 64 #else 65 USE(option); 66 return CPUFeatures(); 67 #endif 68 } 69 70 void CPUFeatures::Combine(const CPUFeatures& other) { 71 features_ |= other.features_; 72 } 73 74 void CPUFeatures::Combine(Feature feature) { 75 if (feature != CPUFeatures::kNone) features_.set(feature); 76 } 77 78 void CPUFeatures::Remove(const CPUFeatures& other) { 79 features_ &= ~other.features_; 80 } 81 82 void CPUFeatures::Remove(Feature feature) { 83 if (feature != CPUFeatures::kNone) features_.reset(feature); 84 } 85 86 bool CPUFeatures::Has(const CPUFeatures& other) const { 87 return (features_ & other.features_) == other.features_; 88 } 89 90 bool CPUFeatures::Has(Feature feature) const { 91 return (feature == CPUFeatures::kNone) || features_[feature]; 92 } 93 94 size_t CPUFeatures::Count() const { return features_.count(); } 95 96 std::ostream& operator<<(std::ostream& os, CPUFeatures::Feature feature) { 97 // clang-format off 98 switch (feature) { 99 #define VIXL_FORMAT_FEATURE(SYMBOL, NAME, CPUINFO) \ 100 case CPUFeatures::SYMBOL: \ 101 return os << NAME; 102 VIXL_CPU_FEATURE_LIST(VIXL_FORMAT_FEATURE) 103 #undef VIXL_FORMAT_FEATURE 104 case CPUFeatures::kNone: 105 return os << "none"; 106 case CPUFeatures::kNumberOfFeatures: 107 VIXL_UNREACHABLE(); 108 } 109 // clang-format on 110 VIXL_UNREACHABLE(); 111 return os; 112 } 113 114 CPUFeatures::const_iterator CPUFeatures::begin() const { 115 // For iterators in general, it's undefined to increment `end()`, but here we 116 // control the implementation and it is safe to do this. 117 return ++end(); 118 } 119 120 CPUFeatures::const_iterator CPUFeatures::end() const { 121 return const_iterator(this, kNone); 122 } 123 124 std::ostream& operator<<(std::ostream& os, const CPUFeatures& features) { 125 bool need_separator = false; 126 for (CPUFeatures::Feature feature : features) { 127 if (need_separator) os << ", "; 128 need_separator = true; 129 os << feature; 130 } 131 return os; 132 } 133 134 bool CPUFeaturesConstIterator::operator==( 135 const CPUFeaturesConstIterator& other) const { 136 VIXL_ASSERT(IsValid()); 137 return (cpu_features_ == other.cpu_features_) && (feature_ == other.feature_); 138 } 139 140 CPUFeaturesConstIterator& CPUFeaturesConstIterator::operator++() { // Prefix 141 VIXL_ASSERT(IsValid()); 142 do { 143 // Find the next feature. The order is unspecified. 144 feature_ = static_cast<CPUFeatures::Feature>(feature_ + 1); 145 if (feature_ == CPUFeatures::kNumberOfFeatures) { 146 feature_ = CPUFeatures::kNone; 147 VIXL_STATIC_ASSERT(CPUFeatures::kNone == -1); 148 } 149 VIXL_ASSERT(CPUFeatures::kNone <= feature_); 150 VIXL_ASSERT(feature_ < CPUFeatures::kNumberOfFeatures); 151 // cpu_features_->Has(kNone) is always true, so this will terminate even if 152 // the features list is empty. 153 } while (!cpu_features_->Has(feature_)); 154 return *this; 155 } 156 157 CPUFeaturesConstIterator CPUFeaturesConstIterator::operator++(int) { // Postfix 158 CPUFeaturesConstIterator result = *this; 159 ++(*this); 160 return result; 161 } 162 163 } // namespace vixl