diff options
Diffstat (limited to 'src/lib/utils/cpuid.h')
| -rw-r--r-- | src/lib/utils/cpuid.h | 125 |
1 files changed, 94 insertions, 31 deletions
diff --git a/src/lib/utils/cpuid.h b/src/lib/utils/cpuid.h index 634305aa1..2bb5a8301 100644 --- a/src/lib/utils/cpuid.h +++ b/src/lib/utils/cpuid.h @@ -1,6 +1,6 @@ /* * Runtime CPU detection -* (C) 2009-2010,2013 Jack Lloyd +* (C) 2009,2010,2013,2017 Jack Lloyd * * Botan is released under the Simplified BSD License (see license.txt) */ @@ -14,9 +14,22 @@ namespace Botan { /** -* A class handling runtime CPU feature detection +* A class handling runtime CPU feature detection. It is limited to +* just the features necessary to implement CPU specific code in Botan, +* rather than being a general purpose utility. * -* Currently this class supports only x86 (via CPUID) and PowerPC (AltiVec detection) +* This class supports: +* +* - x86 features using CPUID. x86 is also the only processor with +* accurate cache line detection currently. +* +* - PowerPC AltiVec detection on Linux, NetBSD, OpenBSD, and Darwin +* +* - ARM NEON and crypto extensions detection. On Linux and Android +* systems which support getauxval, that is used to access CPU +* feature information. Otherwise a relatively portable but +* thread-unsafe mechanism involving executing probe functions which +* catching SIGILL signal is used. */ class BOTAN_DLL CPUID { @@ -35,7 +48,7 @@ class BOTAN_DLL CPUID */ static size_t cache_line_size() { - if(!g_initialized) + if(g_processor_features == 0) { initialize(); } @@ -44,38 +57,51 @@ class BOTAN_DLL CPUID static bool is_little_endian() { - if(!g_initialized) + if(g_processor_features == 0) { initialize(); } return g_little_endian; } - enum CPUID_bits { + enum CPUID_bits : uint64_t { #if defined(BOTAN_TARGET_CPU_IS_X86_FAMILY) - // This matches the layout of cpuid(1) - CPUID_RDTSC_BIT = 4, - CPUID_SSE2_BIT = 26, - CPUID_CLMUL_BIT = 33, - CPUID_SSSE3_BIT = 41, - CPUID_SSE41_BIT = 51, - CPUID_SSE42_BIT = 52, - CPUID_AESNI_BIT = 57, - CPUID_RDRAND_BIT = 62, - - CPUID_AVX2_BIT = 64+5, - CPUID_BMI2_BIT = 64+8, - CPUID_AVX512F_BIT = 64+16, - CPUID_RDSEED_BIT = 64+18, - CPUID_ADX_BIT = 64+19, - CPUID_SHA_BIT = 64+29, + // These values have no relation to cpuid bitfields + + // SIMD instruction sets + CPUID_SSE2_BIT = (1ULL << 0), + CPUID_SSSE3_BIT = (1ULL << 1), + CPUID_SSE41_BIT = (1ULL << 2), + CPUID_SSE42_BIT = (1ULL << 3), + CPUID_AVX2_BIT = (1ULL << 4), + CPUID_AVX512F_BIT = (1ULL << 5), + + // Misc useful instructions + CPUID_RDTSC_BIT = (1ULL << 10), + CPUID_BMI2_BIT = (1ULL << 11), + CPUID_ADX_BIT = (1ULL << 12), + + // Crypto-specific ISAs + CPUID_AESNI_BIT = (1ULL << 16), + CPUID_CLMUL_BIT = (1ULL << 17), + CPUID_RDRAND_BIT = (1ULL << 18), + CPUID_RDSEED_BIT = (1ULL << 19), + CPUID_SHA_BIT = (1ULL << 20), #endif #if defined(BOTAN_TARGET_CPU_IS_PPC_FAMILY) - CPUID_ALTIVEC_BIT = 0 + CPUID_ALTIVEC_BIT = (1ULL << 0), #endif - // TODO: ARMv8 feature detection +#if defined(BOTAN_TARGET_CPU_IS_ARM_FAMILY) + CPUID_ARM_NEON_BIT = (1ULL << 0), + CPUID_ARM_AES_BIT = (1ULL << 16), + CPUID_ARM_PMULL_BIT = (1ULL << 17), + CPUID_ARM_SHA1_BIT = (1ULL << 18), + CPUID_ARM_SHA2_BIT = (1ULL << 19), +#endif + + CPUID_INITIALIZED_BIT = (1ULL << 63) }; #if defined(BOTAN_TARGET_CPU_IS_PPC_FAMILY) @@ -86,6 +112,38 @@ class BOTAN_DLL CPUID { return has_cpuid_bit(CPUID_ALTIVEC_BIT); } #endif +#if defined(BOTAN_TARGET_CPU_IS_ARM_FAMILY) + /** + * Check if the processor supports NEON SIMD + */ + static bool has_neon() + { return has_cpuid_bit(CPUID_ARM_NEON_BIT); } + + /** + * Check if the processor supports ARMv8 SHA1 + */ + static bool has_arm_sha1() + { return has_cpuid_bit(CPUID_ARM_SHA1_BIT); } + + /** + * Check if the processor supports ARMv8 SHA2 + */ + static bool has_arm_sha2() + { return has_cpuid_bit(CPUID_ARM_SHA2_BIT); } + + /** + * Check if the processor supports ARMv8 AES + */ + static bool has_arm_aes() + { return has_cpuid_bit(CPUID_ARM_AES_BIT); } + + /** + * Check if the processor supports ARMv8 PMULL + */ + static bool has_arm_pmull() + { return has_cpuid_bit(CPUID_ARM_PMULL_BIT); } +#endif + #if defined(BOTAN_TARGET_CPU_IS_X86_FAMILY) /** @@ -176,26 +234,31 @@ class BOTAN_DLL CPUID /* * Clear a CPUID bit * Call CPUID::initialize to reset + * + * This is only exposed for testing, don't use unless you know + * what you are doing. */ static void clear_cpuid_bit(CPUID_bits bit) { - const uint64_t mask = ~(static_cast<uint64_t>(1) << (bit % 64)); - g_processor_flags[bit/64] &= mask; + const uint64_t mask = ~(static_cast<uint64_t>(bit)); + g_processor_features &= mask; } + /* + * Don't call this function, use CPUID::has_xxx above + * It should have been private. + */ static bool has_cpuid_bit(CPUID_bits elem) { - if(!g_initialized) + if(g_processor_features == 0) initialize(); - const size_t bit = static_cast<size_t>(elem); - return ((g_processor_flags[bit/64] >> (bit % 64)) & 1); + return ((g_processor_features & static_cast<uint64_t>(elem)) != 0); } private: - static bool g_initialized; static bool g_little_endian; static size_t g_cache_line_size; - static uint64_t g_processor_flags[2]; + static uint64_t g_processor_features; }; } |