diff options
Diffstat (limited to 'config')
| -rw-r--r-- | config/c-compiler.m4 | 28 |
1 files changed, 16 insertions, 12 deletions
diff --git a/config/c-compiler.m4 b/config/c-compiler.m4 index 8534cc54c13..3712e81e38c 100644 --- a/config/c-compiler.m4 +++ b/config/c-compiler.m4 @@ -553,16 +553,20 @@ fi])# PGAC_HAVE_GCC__ATOMIC_INT64_CAS # the other ones are, on x86-64 platforms) # # If the intrinsics are supported, sets pgac_sse42_crc32_intrinsics. +# +# To detect the case where the compiler knows the function but library support +# is missing, we must link not just compile, and store the results in global +# variables so the compiler doesn't optimize away the call. AC_DEFUN([PGAC_SSE42_CRC32_INTRINSICS], [define([Ac_cachevar], [AS_TR_SH([pgac_cv_sse42_crc32_intrinsics])])dnl AC_CACHE_CHECK([for _mm_crc32_u8 and _mm_crc32_u32], [Ac_cachevar], [AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <nmmintrin.h> + unsigned int crc; #if defined(__has_attribute) && __has_attribute (target) __attribute__((target("sse4.2"))) #endif static int crc32_sse42_test(void) { - unsigned int crc = 0; crc = _mm_crc32_u8(crc, 0); crc = _mm_crc32_u32(crc, 0); /* return computed value, to prevent the above being optimized away */ @@ -593,9 +597,9 @@ AC_DEFUN([PGAC_ARMV8_CRC32C_INTRINSICS], AC_CACHE_CHECK([for __crc32cb, __crc32ch, __crc32cw, and __crc32cd with CFLAGS=$1], [Ac_cachevar], [pgac_save_CFLAGS=$CFLAGS CFLAGS="$pgac_save_CFLAGS $1" -AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <arm_acle.h>], - [unsigned int crc = 0; - crc = __crc32cb(crc, 0); +AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <arm_acle.h> +unsigned int crc;], + [crc = __crc32cb(crc, 0); crc = __crc32ch(crc, 0); crc = __crc32cw(crc, 0); crc = __crc32cd(crc, 0); @@ -628,9 +632,8 @@ AC_DEFUN([PGAC_LOONGARCH_CRC32C_INTRINSICS], AC_CACHE_CHECK( [for __builtin_loongarch_crcc_w_b_w, __builtin_loongarch_crcc_w_h_w, __builtin_loongarch_crcc_w_w_w and __builtin_loongarch_crcc_w_d_w], [Ac_cachevar], -[AC_LINK_IFELSE([AC_LANG_PROGRAM([], - [unsigned int crc = 0; - crc = __builtin_loongarch_crcc_w_b_w(0, crc); +[AC_LINK_IFELSE([AC_LANG_PROGRAM([unsigned int crc;], + [crc = __builtin_loongarch_crcc_w_b_w(0, crc); crc = __builtin_loongarch_crcc_w_h_w(0, crc); crc = __builtin_loongarch_crcc_w_w_w(0, crc); crc = __builtin_loongarch_crcc_w_d_w(0, crc); @@ -680,22 +683,23 @@ undefine([Ac_cachevar])dnl AC_DEFUN([PGAC_AVX512_POPCNT_INTRINSICS], [define([Ac_cachevar], [AS_TR_SH([pgac_cv_avx512_popcnt_intrinsics])])dnl AC_CACHE_CHECK([for _mm512_popcnt_epi64], [Ac_cachevar], -[AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <immintrin.h> +[AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <immintrin.h> #include <stdint.h> + char buf[sizeof(__m512i)]; + #if defined(__has_attribute) && __has_attribute (target) __attribute__((target("avx512vpopcntdq,avx512bw"))) #endif static int popcount_test(void) { - const char buf@<:@sizeof(__m512i)@:>@; int64_t popcnt = 0; __m512i accum = _mm512_setzero_si512(); - const __m512i val = _mm512_maskz_loadu_epi8((__mmask64) 0xf0f0f0f0f0f0f0f0, (const __m512i *) buf); - const __m512i cnt = _mm512_popcnt_epi64(val); + __m512i val = _mm512_maskz_loadu_epi8((__mmask64) 0xf0f0f0f0f0f0f0f0, (const __m512i *) buf); + __m512i cnt = _mm512_popcnt_epi64(val); accum = _mm512_add_epi64(accum, cnt); popcnt = _mm512_reduce_add_epi64(accum); return (int) popcnt; - }], + }]], [return popcount_test();])], [Ac_cachevar=yes], [Ac_cachevar=no])]) |