diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/port/pg_popcount_avx512_choose.c | 80 |
1 files changed, 47 insertions, 33 deletions
diff --git a/src/port/pg_popcount_avx512_choose.c b/src/port/pg_popcount_avx512_choose.c index ae3fa3d3067..b37107803a8 100644 --- a/src/port/pg_popcount_avx512_choose.c +++ b/src/port/pg_popcount_avx512_choose.c @@ -34,39 +34,13 @@ #ifdef TRY_POPCNT_FAST /* - * Returns true if the CPU supports the instructions required for the AVX-512 - * pg_popcount() implementation. + * Does CPUID say there's support for XSAVE instructions? */ -bool -pg_popcount_avx512_available(void) +static inline bool +xsave_available(void) { unsigned int exx[4] = {0, 0, 0, 0}; - /* Does CPUID say there's support for AVX-512 popcount instructions? */ -#if defined(HAVE__GET_CPUID_COUNT) - __get_cpuid_count(7, 0, &exx[0], &exx[1], &exx[2], &exx[3]); -#elif defined(HAVE__CPUIDEX) - __cpuidex(exx, 7, 0); -#else -#error cpuid instruction not available -#endif - if ((exx[2] & (1 << 14)) == 0) /* avx512-vpopcntdq */ - return false; - - /* Does CPUID say there's support for AVX-512 byte and word instructions? */ - memset(exx, 0, sizeof(exx)); -#if defined(HAVE__GET_CPUID_COUNT) - __get_cpuid_count(7, 0, &exx[0], &exx[1], &exx[2], &exx[3]); -#elif defined(HAVE__CPUIDEX) - __cpuidex(exx, 7, 0); -#else -#error cpuid instruction not available -#endif - if ((exx[1] & (1 << 30)) == 0) /* avx512-bw */ - return false; - - /* Does CPUID say there's support for XSAVE instructions? */ - memset(exx, 0, sizeof(exx)); #if defined(HAVE__GET_CPUID) __get_cpuid(1, &exx[0], &exx[1], &exx[2], &exx[3]); #elif defined(HAVE__CPUID) @@ -74,15 +48,55 @@ pg_popcount_avx512_available(void) #else #error cpuid instruction not available #endif - if ((exx[2] & (1 << 26)) == 0) /* xsave */ - return false; + return (exx[2] & (1 << 27)) != 0; /* osxsave */ +} - /* Does XGETBV say the ZMM registers are enabled? */ +/* + * Does XGETBV say the ZMM registers are enabled? + * + * NB: Caller is responsible for verifying that xsave_available() returns true + * before calling this. + */ +static inline bool +zmm_regs_available(void) +{ #ifdef HAVE_XSAVE_INTRINSICS - return (_xgetbv(0) & 0xe0) != 0; + return (_xgetbv(0) & 0xe6) == 0xe6; #else return false; #endif } +/* + * Does CPUID say there's support for AVX-512 popcount and byte-and-word + * instructions? + */ +static inline bool +avx512_popcnt_available(void) +{ + unsigned int exx[4] = {0, 0, 0, 0}; + +#if defined(HAVE__GET_CPUID_COUNT) + __get_cpuid_count(7, 0, &exx[0], &exx[1], &exx[2], &exx[3]); +#elif defined(HAVE__CPUIDEX) + __cpuidex(exx, 7, 0); +#else +#error cpuid instruction not available +#endif + return (exx[2] & (1 << 14)) != 0 && /* avx512-vpopcntdq */ + (exx[1] & (1 << 30)) != 0; /* avx512-bw */ +} + +/* + * Returns true if the CPU supports the instructions required for the AVX-512 + * pg_popcount() implementation. + */ +bool +pg_popcount_avx512_available(void) +{ + return xsave_available() && + zmm_regs_available() && + avx512_popcnt_available(); +} + #endif /* TRY_POPCNT_FAST */ |