From 91a74d361461494dd546467e83bc36c24185d6e7 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Tue, 13 Jun 2023 21:10:24 -0700 Subject: [PATCH] wc: port to kernels that disable XSAVE YMM Problem reported by Dave Hansen . Apply similar change to cksum and pclmul, too. * NEWS: Mention wc fix. * configure.ac (cpuid_exists, get_cpuid_count_exists): Remove. All uses removed, since we no longer use __get_cpuid or __get_cpuid_count. (pclmul_intrinsic_exists, avx2_intrinsic_exists): Set to no if __builtin_cpu_supports calls cannot be compiled. (HAVE_PCLMUL_INTRINSIC, HAVE_AVX2_INTRINSIC): Remove; unused. Simplify surrounding code because of this. * src/cksum.c (pclmul_supported): * src/wc.c (avx2_supported): Use __builtin_cpu_supports instead of doing it by hand. Simplify surrounding code because of this. --- NEWS | 3 +++ configure.ac | 67 ++++++++-------------------------------------------- src/cksum.c | 26 +++++--------------- src/wc.c | 50 +++++---------------------------------- 4 files changed, 25 insertions(+), 121 deletions(-) diff --git a/NEWS b/NEWS index 7df9ff5b0..3350f9871 100644 --- a/NEWS +++ b/NEWS @@ -29,6 +29,9 @@ GNU coreutils NEWS -*- outline -*- 'pr --length=1 --double-space' no longer enters an infinite loop. [This bug was present in "the beginning".] + 'wc -l' no longer crashes on x86 Linux kernels that disable XSAVE YMM. + [bug introduced in coreutils-9.0] + ** Changes in behavior 'cp -v' and 'mv -v' will no longer output a message for each file skipped diff --git a/configure.ac b/configure.ac index 520de8184..48dea9d01 100644 --- a/configure.ac +++ b/configure.ac @@ -548,27 +548,6 @@ CFLAGS=$ac_save_CFLAGS LDFLAGS=$ac_save_LDFLAGS ac_c_werror_flag=$cu_save_c_werror_flag -AC_MSG_CHECKING([if __get_cpuid available]) -AC_LINK_IFELSE( - [AC_LANG_SOURCE([[ - #include - - int - main (void) - { - unsigned int eax, ebx, ecx, edx; - __get_cpuid (1, &eax, &ebx, &ecx, &edx); - return 1; - } - ]]) - ],[ - AC_MSG_RESULT([yes]) - AC_DEFINE([HAVE_CPUID], [1], [__get_cpuid available]) - cpuid_exists=yes - ],[ - AC_MSG_RESULT([no]) - ]) - ac_save_CFLAGS=$CFLAGS CFLAGS="-mavx -mpclmul $CFLAGS" AC_MSG_CHECKING([if pclmul intrinsic exists]) @@ -582,46 +561,23 @@ AC_COMPILE_IFELSE( __m128i a, b; a = _mm_clmulepi64_si128 (a, b, 0x00); a = _mm_shuffle_epi8 (a, b); - return 1; + return __builtin_cpu_supports ("pclmul"); } ]]) ],[ - AC_MSG_RESULT([yes]) - AC_DEFINE([HAVE_PCLMUL_INTRINSIC], [1], [pclmul intrinsic exists]) pclmul_intrinsic_exists=yes ],[ - AC_MSG_RESULT([no]) + pclmul_intrinsic_exists=no ]) -if test "x$cpuid_exists" = "xyes" && - test "x$pclmul_intrinsic_exists" = "xyes"; then +AC_MSG_RESULT([$pclmul_intrinsic_exists]) +if test $pclmul_intrinsic_exists = yes; then AC_DEFINE([USE_PCLMUL_CRC32], [1], [CRC32 calculation by pclmul hardware instruction enabled]) fi AM_CONDITIONAL([USE_PCLMUL_CRC32], - [test "x$cpuid_exists" = "xyes" && - test "x$pclmul_intrinsic_exists" = "xyes"]) + [test $pclmul_intrinsic_exists = yes]) CFLAGS=$ac_save_CFLAGS -AC_MSG_CHECKING([if __get_cpuid_count exists]) -AC_LINK_IFELSE( - [AC_LANG_SOURCE([[ - #include - - int - main (void) - { - unsigned int eax = 0, ebx = 0, ecx = 0, edx = 0; - __get_cpuid_count (7, 0, &eax, &ebx, &ecx, &edx); - return 1; - } - ]]) - ],[ - AC_MSG_RESULT([yes]) - get_cpuid_count_exists=yes - ],[ - AC_MSG_RESULT([no]) - ]) - CFLAGS="-mavx2 $CFLAGS" AC_MSG_CHECKING([if avx2 intrinstics exists]) AC_COMPILE_IFELSE( @@ -633,23 +589,20 @@ AC_COMPILE_IFELSE( { __m256i a, b; a = _mm256_sad_epu8 (a, b); - return 1; + return __builtin_cpu_supports ("avx2"); } ]]) ],[ - AC_MSG_RESULT([yes]) - AC_DEFINE([HAVE_AVX2_INTRINSIC], [1], [avx2 intrinsics exists]) avx2_intrinsic_exists=yes ],[ - AC_MSG_RESULT([no]) + avx2_intrinsic_exists=no ]) -if test "x$get_cpuid_count_exists" = "xyes" && - test "x$avx2_intrinsic_exists" = "xyes"; then +AC_MSG_RESULT([$avx2_intrinsic_exists]) +if test $avx2_intrinsic_exists = yes; then AC_DEFINE([USE_AVX2_WC_LINECOUNT], [1], [Counting lines with AVX2 enabled]) fi AM_CONDITIONAL([USE_AVX2_WC_LINECOUNT], - [test "x$get_cpuid_count_exists" = "xyes" && - test "x$avx2_intrinsic_exists" = "xyes"]) + [test $avx2_intrinsic_exists = yes]) CFLAGS=$ac_save_CFLAGS diff --git a/src/cksum.c b/src/cksum.c index 85afab0ac..631ac3449 100644 --- a/src/cksum.c +++ b/src/cksum.c @@ -160,29 +160,15 @@ static bool pclmul_supported (void) { # if USE_PCLMUL_CRC32 - unsigned int eax = 0; - unsigned int ebx = 0; - unsigned int ecx = 0; - unsigned int edx = 0; - - if (! __get_cpuid (1, &eax, &ebx, &ecx, &edx)) - { - if (cksum_debug) - error (0, 0, "%s", _("failed to get cpuid")); - return false; - } - - if (! (ecx & bit_PCLMUL) || ! (ecx & bit_AVX)) - { - if (cksum_debug) - error (0, 0, "%s", _("pclmul support not detected")); - return false; - } + bool pclmul_enabled = 0 < __builtin_cpu_supports ("pclmul"); if (cksum_debug) - error (0, 0, "%s", _("using pclmul hardware support")); + error (0, 0, "%s", + (pclmul_enabled + ? _("using pclmul hardware support") + : _("pclmul support not detected"))); - return true; + return pclmul_enabled; # else if (cksum_debug) error (0, 0, "%s", _("using generic hardware support")); diff --git a/src/wc.c b/src/wc.c index becceda98..3708d0b8f 100644 --- a/src/wc.c +++ b/src/wc.c @@ -157,52 +157,14 @@ static enum total_type total_mode = total_auto; static bool avx2_supported (void) { - unsigned int eax = 0; - unsigned int ebx = 0; - unsigned int ecx = 0; - unsigned int edx = 0; - bool getcpuid_ok = false; - bool avx_enabled = false; - - if (__get_cpuid (1, &eax, &ebx, &ecx, &edx)) - { - getcpuid_ok = true; - if (ecx & bit_OSXSAVE) - avx_enabled = true; /* Support is not disabled. */ - } - - - if (avx_enabled) - { - eax = ebx = ecx = edx = 0; - if (! __get_cpuid_count (7, 0, &eax, &ebx, &ecx, &edx)) - getcpuid_ok = false; - else - { - if (! (ebx & bit_AVX2)) - avx_enabled = false; /* Hardware doesn't support it. */ - } - } + bool avx_enabled = 0 < __builtin_cpu_supports ("avx2"); + if (debug) + error (0, 0, (avx_enabled + ? _("using avx2 hardware support") + : _("avx2 support not detected"))); - if (! getcpuid_ok) - { - if (debug) - error (0, 0, "%s", _("failed to get cpuid")); - return false; - } - else if (! avx_enabled) - { - if (debug) - error (0, 0, "%s", _("avx2 support not detected")); - return false; - } - else - { - if (debug) - error (0, 0, "%s", _("using avx2 hardware support")); - return true; - } + return avx_enabled; } #endif -- 2.40.1