x86-64: Require BMI2 for AVX2 (raw|w)memchr implementations

The AVX2 memchr, rawmemchr and wmemchr implementations use the 'bzhi'
and 'sarx' instructions, which belongs to the BMI2 CPU feature.

Fixes: acfd088a19 ("x86: Optimize memchr-avx2.S")
Partially resolves: BZ #29611

Reviewed-by: Noah Goldstein  <goldstein.w.n@gmail.com>
(cherry picked from commit e3e7fab7fe)
This commit is contained in:
Aurelien Jarno 2022-10-03 23:16:46 +02:00
parent 67e863742d
commit 94b9c1b640

View File

@ -41,10 +41,12 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
/* Support sysdeps/x86_64/multiarch/memchr.c. */
IFUNC_IMPL (i, name, memchr,
IFUNC_IMPL_ADD (array, i, memchr,
CPU_FEATURE_USABLE (AVX2),
(CPU_FEATURE_USABLE (AVX2)
&& CPU_FEATURE_USABLE (BMI2)),
__memchr_avx2)
IFUNC_IMPL_ADD (array, i, memchr,
(CPU_FEATURE_USABLE (AVX2)
&& CPU_FEATURE_USABLE (BMI2)
&& CPU_FEATURE_USABLE (RTM)),
__memchr_avx2_rtm)
IFUNC_IMPL_ADD (array, i, memchr,
@ -283,10 +285,12 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
/* Support sysdeps/x86_64/multiarch/rawmemchr.c. */
IFUNC_IMPL (i, name, rawmemchr,
IFUNC_IMPL_ADD (array, i, rawmemchr,
CPU_FEATURE_USABLE (AVX2),
(CPU_FEATURE_USABLE (AVX2)
&& CPU_FEATURE_USABLE (BMI2)),
__rawmemchr_avx2)
IFUNC_IMPL_ADD (array, i, rawmemchr,
(CPU_FEATURE_USABLE (AVX2)
&& CPU_FEATURE_USABLE (BMI2)
&& CPU_FEATURE_USABLE (RTM)),
__rawmemchr_avx2_rtm)
IFUNC_IMPL_ADD (array, i, rawmemchr,
@ -787,10 +791,12 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
/* Support sysdeps/x86_64/multiarch/wmemchr.c. */
IFUNC_IMPL (i, name, wmemchr,
IFUNC_IMPL_ADD (array, i, wmemchr,
CPU_FEATURE_USABLE (AVX2),
(CPU_FEATURE_USABLE (AVX2)
&& CPU_FEATURE_USABLE (BMI2)),
__wmemchr_avx2)
IFUNC_IMPL_ADD (array, i, wmemchr,
(CPU_FEATURE_USABLE (AVX2)
&& CPU_FEATURE_USABLE (BMI2)
&& CPU_FEATURE_USABLE (RTM)),
__wmemchr_avx2_rtm)
IFUNC_IMPL_ADD (array, i, wmemchr,