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commit 94b9c1b6409e34f3f0b2339f77d7ee78087422eb
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Author: Aurelien Jarno <aurelien@aurel32.net>
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Date:   Mon Oct 3 23:16:46 2022 +0200
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    x86-64: Require BMI2 for AVX2 (raw|w)memchr implementations
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    The AVX2 memchr, rawmemchr and wmemchr implementations use the 'bzhi'
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    and 'sarx' instructions, which belongs to the BMI2 CPU feature.
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    Fixes: acfd088a1963 ("x86: Optimize memchr-avx2.S")
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    Partially resolves: BZ #29611
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    Reviewed-by: Noah Goldstein  <goldstein.w.n@gmail.com>
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    (cherry picked from commit e3e7fab7fe5186d18ca2046d99ba321c27db30ad)
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diff --git a/sysdeps/x86_64/multiarch/ifunc-impl-list.c b/sysdeps/x86_64/multiarch/ifunc-impl-list.c
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index e76a991dc671c1a9..81640cf00664e3ed 100644
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--- a/sysdeps/x86_64/multiarch/ifunc-impl-list.c
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+++ b/sysdeps/x86_64/multiarch/ifunc-impl-list.c
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@@ -41,10 +41,12 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
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   /* Support sysdeps/x86_64/multiarch/memchr.c.  */
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   IFUNC_IMPL (i, name, memchr,
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 	      IFUNC_IMPL_ADD (array, i, memchr,
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-			      CPU_FEATURE_USABLE (AVX2),
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+			      (CPU_FEATURE_USABLE (AVX2)
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+			       && CPU_FEATURE_USABLE (BMI2)),
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 			      __memchr_avx2)
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 	      IFUNC_IMPL_ADD (array, i, memchr,
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 			      (CPU_FEATURE_USABLE (AVX2)
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+			       && CPU_FEATURE_USABLE (BMI2)
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 			       && CPU_FEATURE_USABLE (RTM)),
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 			      __memchr_avx2_rtm)
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 	      IFUNC_IMPL_ADD (array, i, memchr,
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@@ -283,10 +285,12 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
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   /* Support sysdeps/x86_64/multiarch/rawmemchr.c.  */
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   IFUNC_IMPL (i, name, rawmemchr,
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 	      IFUNC_IMPL_ADD (array, i, rawmemchr,
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-			      CPU_FEATURE_USABLE (AVX2),
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+			      (CPU_FEATURE_USABLE (AVX2)
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+			       && CPU_FEATURE_USABLE (BMI2)),
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 			      __rawmemchr_avx2)
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 	      IFUNC_IMPL_ADD (array, i, rawmemchr,
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 			      (CPU_FEATURE_USABLE (AVX2)
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+			       && CPU_FEATURE_USABLE (BMI2)
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 			       && CPU_FEATURE_USABLE (RTM)),
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 			      __rawmemchr_avx2_rtm)
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 	      IFUNC_IMPL_ADD (array, i, rawmemchr,
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@@ -787,10 +791,12 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
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   /* Support sysdeps/x86_64/multiarch/wmemchr.c.  */
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   IFUNC_IMPL (i, name, wmemchr,
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 	      IFUNC_IMPL_ADD (array, i, wmemchr,
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-			      CPU_FEATURE_USABLE (AVX2),
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+			      (CPU_FEATURE_USABLE (AVX2)
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+			       && CPU_FEATURE_USABLE (BMI2)),
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 			      __wmemchr_avx2)
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 	      IFUNC_IMPL_ADD (array, i, wmemchr,
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 			      (CPU_FEATURE_USABLE (AVX2)
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+			       && CPU_FEATURE_USABLE (BMI2)
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 			       && CPU_FEATURE_USABLE (RTM)),
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 			      __wmemchr_avx2_rtm)
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 	      IFUNC_IMPL_ADD (array, i, wmemchr,