1 // Copyright 2017 The Abseil Authors. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // https://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #ifndef ABSL_RANDOM_INTERNAL_PLATFORM_H_ 16 #define ABSL_RANDOM_INTERNAL_PLATFORM_H_ 17 18 // HERMETIC NOTE: The randen_hwaes target must not introduce duplicate 19 // symbols from arbitrary system and other headers, since it may be built 20 // with different flags from other targets, using different levels of 21 // optimization, potentially introducing ODR violations. 22 23 // ----------------------------------------------------------------------------- 24 // Platform Feature Checks 25 // ----------------------------------------------------------------------------- 26 27 // Currently supported operating systems and associated preprocessor 28 // symbols: 29 // 30 // Linux and Linux-derived __linux__ 31 // Android __ANDROID__ (implies __linux__) 32 // Linux (non-Android) __linux__ && !__ANDROID__ 33 // Darwin (macOS and iOS) __APPLE__ 34 // Akaros (http://akaros.org) __ros__ 35 // Windows _WIN32 36 // NaCL __native_client__ 37 // AsmJS __asmjs__ 38 // WebAssembly __wasm__ 39 // Fuchsia __Fuchsia__ 40 // 41 // Note that since Android defines both __ANDROID__ and __linux__, one 42 // may probe for either Linux or Android by simply testing for __linux__. 43 // 44 // NOTE: For __APPLE__ platforms, we use #include <TargetConditionals.h> 45 // to distinguish os variants. 46 // 47 // http://nadeausoftware.com/articles/2012/01/c_c_tip_how_use_compiler_predefined_macros_detect_operating_system 48 49 #if defined(__APPLE__) 50 #include <TargetConditionals.h> 51 #endif 52 53 // ----------------------------------------------------------------------------- 54 // Architecture Checks 55 // ----------------------------------------------------------------------------- 56 57 // These preprocessor directives are trying to determine CPU architecture, 58 // including necessary headers to support hardware AES. 59 // 60 // ABSL_ARCH_{X86/PPC/ARM} macros determine the platform. 61 #if defined(__x86_64__) || defined(__x86_64) || defined(_M_AMD64) || \ 62 defined(_M_X64) 63 #define ABSL_ARCH_X86_64 64 #elif defined(__i386) || defined(_M_IX86) 65 #define ABSL_ARCH_X86_32 66 #elif defined(__aarch64__) || defined(__arm64__) || defined(_M_ARM64) 67 #define ABSL_ARCH_AARCH64 68 #elif defined(__arm__) || defined(__ARMEL__) || defined(_M_ARM) 69 #define ABSL_ARCH_ARM 70 #elif defined(__powerpc64__) || defined(__PPC64__) || defined(__powerpc__) || \ 71 defined(__ppc__) || defined(__PPC__) 72 #define ABSL_ARCH_PPC 73 #else 74 // Unsupported architecture. 75 // * https://sourceforge.net/p/predef/wiki/Architectures/ 76 // * https://msdn.microsoft.com/en-us/library/b0084kay.aspx 77 // * for gcc, clang: "echo | gcc -E -dM -" 78 #endif 79 80 // ----------------------------------------------------------------------------- 81 // Attribute Checks 82 // ----------------------------------------------------------------------------- 83 84 // ABSL_RANDOM_INTERNAL_RESTRICT annotates whether pointers may be considered 85 // to be unaliased. 86 #if defined(__clang__) || defined(__GNUC__) 87 #define ABSL_RANDOM_INTERNAL_RESTRICT __restrict__ 88 #elif defined(_MSC_VER) 89 #define ABSL_RANDOM_INTERNAL_RESTRICT __restrict 90 #else 91 #define ABSL_RANDOM_INTERNAL_RESTRICT 92 #endif 93 94 // ABSL_HAVE_ACCELERATED_AES indicates whether the currently active compiler 95 // flags (e.g. -maes) allow using hardware accelerated AES instructions, which 96 // implies us assuming that the target platform supports them. 97 #define ABSL_HAVE_ACCELERATED_AES 0 98 99 #if defined(ABSL_ARCH_X86_64) 100 101 #if defined(__AES__) || defined(__AVX__) 102 #undef ABSL_HAVE_ACCELERATED_AES 103 #define ABSL_HAVE_ACCELERATED_AES 1 104 #endif 105 106 #elif defined(ABSL_ARCH_PPC) 107 108 // Rely on VSX and CRYPTO extensions for vcipher on PowerPC. 109 #if (defined(__VEC__) || defined(__ALTIVEC__)) && defined(__VSX__) && \ 110 defined(__CRYPTO__) 111 #undef ABSL_HAVE_ACCELERATED_AES 112 #define ABSL_HAVE_ACCELERATED_AES 1 113 #endif 114 115 #elif defined(ABSL_ARCH_ARM) || defined(ABSL_ARCH_AARCH64) 116 117 // http://infocenter.arm.com/help/topic/com.arm.doc.ihi0053c/IHI0053C_acle_2_0.pdf 118 // Rely on NEON+CRYPTO extensions for ARM. 119 #if defined(__ARM_NEON) && defined(__ARM_FEATURE_CRYPTO) 120 #undef ABSL_HAVE_ACCELERATED_AES 121 #define ABSL_HAVE_ACCELERATED_AES 1 122 #endif 123 124 #endif 125 126 // NaCl does not allow AES. 127 #if defined(__native_client__) 128 #undef ABSL_HAVE_ACCELERATED_AES 129 #define ABSL_HAVE_ACCELERATED_AES 0 130 #endif 131 132 // ABSL_RANDOM_INTERNAL_AES_DISPATCH indicates whether the currently active 133 // platform has, or should use run-time dispatch for selecting the 134 // acclerated Randen implementation. 135 #define ABSL_RANDOM_INTERNAL_AES_DISPATCH 0 136 137 #if defined(ABSL_ARCH_X86_64) 138 // Dispatch is available on x86_64 139 #undef ABSL_RANDOM_INTERNAL_AES_DISPATCH 140 #define ABSL_RANDOM_INTERNAL_AES_DISPATCH 1 141 #elif defined(__linux__) && defined(ABSL_ARCH_PPC) 142 // Or when running linux PPC 143 #undef ABSL_RANDOM_INTERNAL_AES_DISPATCH 144 #define ABSL_RANDOM_INTERNAL_AES_DISPATCH 1 145 #elif defined(__linux__) && defined(ABSL_ARCH_AARCH64) 146 // Or when running linux AArch64 147 #undef ABSL_RANDOM_INTERNAL_AES_DISPATCH 148 #define ABSL_RANDOM_INTERNAL_AES_DISPATCH 1 149 #elif defined(__linux__) && defined(ABSL_ARCH_ARM) && (__ARM_ARCH >= 8) 150 // Or when running linux ARM v8 or higher. 151 // (This captures a lot of Android configurations.) 152 #undef ABSL_RANDOM_INTERNAL_AES_DISPATCH 153 #define ABSL_RANDOM_INTERNAL_AES_DISPATCH 1 154 #endif 155 156 // NaCl does not allow dispatch. 157 #if defined(__native_client__) 158 #undef ABSL_RANDOM_INTERNAL_AES_DISPATCH 159 #define ABSL_RANDOM_INTERNAL_AES_DISPATCH 0 160 #endif 161 162 // iOS does not support dispatch, even on x86, since applications 163 // should be bundled as fat binaries, with a different build tailored for 164 // each specific supported platform/architecture. 165 #if (defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE) || \ 166 (defined(TARGET_OS_IPHONE_SIMULATOR) && TARGET_OS_IPHONE_SIMULATOR) 167 #undef ABSL_RANDOM_INTERNAL_AES_DISPATCH 168 #define ABSL_RANDOM_INTERNAL_AES_DISPATCH 0 169 #endif 170 171 #endif // ABSL_RANDOM_INTERNAL_PLATFORM_H_ 172