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From: "H.J. Lu" <hjl.tools@gmail.com>
To: Noah Goldstein <goldstein.w.n@gmail.com>
Cc: GNU C Library <libc-alpha@sourceware.org>,
	"Carlos O'Donell" <carlos@systemhalted.org>
Subject: Re: [PATCH v10 2/2] x86: Add support for compiling {raw|w}memchr with high ISA level
Date: Wed, 22 Jun 2022 15:14:12 -0700	[thread overview]
Message-ID: <CAMe9rOpizoFV1i+4YNOvfZ6tX1HdriHt0+VZ6BE+N_=s4AdX+g@mail.gmail.com> (raw)
In-Reply-To: <CAFUsyfKknj4Swg0AACS9gbmvHDcj0pqMnMr2byxpj_tC+41xBQ@mail.gmail.com>

On Wed, Jun 22, 2022 at 3:04 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
>
> On Wed, Jun 22, 2022 at 2:52 PM H.J. Lu <hjl.tools@gmail.com> wrote:
> >
> > On Wed, Jun 22, 2022 at 1:58 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
> > >
> > > 1. Refactor files so that all implementations for in the multiarch
> > >    directory.
> > >     - Essentially moved sse2 {raw|w}memchr.S implementation to
> > >       multiarch/{raw|w}memchr-sse2.S
> > >
> > >     - The non-multiarch {raw|w}memchr.S file now only includes one of
> > >       the implementations in the multiarch directory based on the
> > >       compiled ISA level (only used for non-multiarch builds.
> > >       Otherwise we go through the ifunc selector).
> > >
> > > 2. Add ISA level build guards to different implementations.
> > >     - I.e memchr-avx2.S which is ISA level 3 will only build if
> > >       compiled ISA level <= 3. Otherwise there is no reason to include
> > >       it as we will always use one of the ISA level 4
> > >       implementations (memchr-evex{-rtm}.S).
> > >
> > > 3. Add new multiarch/rtld-{raw}memchr.S that just include the
> > >    non-multiarch {raw}memchr.S which will in turn select the best
> > >    implementation based on the compiled ISA level.
> > >
> > > 4. Refactor the ifunc selector and ifunc implementation list to use
> > >    the ISA level aware wrapper macros that allow functions below the
> > >    compiled ISA level (with a guranteed replacement) to be skipped.
> > >     - Guranteed replacement essentially means that for any ISA level
> > >       build there must be a function that the baseline of the ISA
> > >       supports. So for {raw|w}memchr.S since there is not ISA level 2
> > >       function, the ISA level 2 build still includes the ISA level
> > >       1 (sse2) function. Once we reach the ISA level 3 build, however,
> > >       {raw|w}memchr-avx2{-rtm}.S will always be sufficient so the ISA
> > >       level 1 implementation ({raw|w}memchr-sse2.S) will not be built.
> > >
> > > Tested with and without multiarch on x86_64 for ISA levels:
> > > {generic, x86-64-v2, x86-64-v3, x86-64-v4}
> > >
> > > And m32 with and without multiarch.
> > > ---
> > >  sysdeps/x86_64/isa-default-impl.h             |   8 +
> > >  sysdeps/x86_64/memchr.S                       | 357 +----------------
> > >  sysdeps/x86_64/multiarch/ifunc-evex.h         |  29 +-
> > >  sysdeps/x86_64/multiarch/ifunc-impl-list.c    |  72 ++--
> > >  sysdeps/x86_64/multiarch/memchr-avx2.S        |   5 +-
> > >  sysdeps/x86_64/multiarch/memchr-evex.S        |   5 +-
> > >  sysdeps/x86_64/multiarch/memchr-sse2.S        | 363 +++++++++++++++++-
> > >  sysdeps/x86_64/multiarch/rawmemchr-avx2-rtm.S |   7 +-
> > >  sysdeps/x86_64/multiarch/rawmemchr-avx2.S     |   7 +-
> > >  sysdeps/x86_64/multiarch/rawmemchr-evex-rtm.S |   8 +-
> > >  sysdeps/x86_64/multiarch/rawmemchr-evex.S     |   7 +-
> > >  sysdeps/x86_64/multiarch/rawmemchr-sse2.S     | 198 +++++++++-
> > >  sysdeps/x86_64/multiarch/rtld-memchr.S        |  18 +
> > >  sysdeps/x86_64/multiarch/rtld-rawmemchr.S     |  18 +
> > >  sysdeps/x86_64/multiarch/wmemchr-avx2-rtm.S   |   7 +-
> > >  sysdeps/x86_64/multiarch/wmemchr-avx2.S       |   7 +-
> > >  sysdeps/x86_64/multiarch/wmemchr-evex-rtm.S   |   8 +-
> > >  sysdeps/x86_64/multiarch/wmemchr-evex.S       |   7 +-
> > >  sysdeps/x86_64/multiarch/wmemchr-sse2.S       |   9 +-
> > >  sysdeps/x86_64/rawmemchr.S                    | 184 +--------
> > >  sysdeps/x86_64/wmemchr.S                      |  28 ++
> > >  21 files changed, 740 insertions(+), 612 deletions(-)
> > >  create mode 100644 sysdeps/x86_64/multiarch/rtld-memchr.S
> > >  create mode 100644 sysdeps/x86_64/multiarch/rtld-rawmemchr.S
> > >  create mode 100644 sysdeps/x86_64/wmemchr.S
> > >
> > > diff --git a/sysdeps/x86_64/isa-default-impl.h b/sysdeps/x86_64/isa-default-impl.h
> > > index 34634668e5..b374a38b8b 100644
> > > --- a/sysdeps/x86_64/isa-default-impl.h
> > > +++ b/sysdeps/x86_64/isa-default-impl.h
> > > @@ -46,4 +46,12 @@
> > >  # error "Unsupported ISA Level!"
> > >  #endif
> > >
> > > +#if IS_IN(rtld) && !defined USE_MULTIARCH
> > > +#  error "RTLD version should only exist in multiarch build"
> > > +#endif
> > > +
> > > +#if defined USE_MULTIARCH && !IS_IN(rtld)
> > > +#  error "Multiarch build should not use ISA_DEFAULT_IMPL without RTLD"
> > > +#endif
> >
> > Please do
> >
> > #if IS_IN (rtld)
> > #else
> > #endif
> >
> > >  #include ISA_DEFAULT_IMPL
> > > diff --git a/sysdeps/x86_64/memchr.S b/sysdeps/x86_64/memchr.S
> > > index a160fd9b00..20b43508c4 100644
> > > --- a/sysdeps/x86_64/memchr.S
> > > +++ b/sysdeps/x86_64/memchr.S
> > > @@ -15,358 +15,13 @@
> > >     License along with the GNU C Library; if not, see
> > >     <https://www.gnu.org/licenses/>.  */
> > >
> > > -#include <sysdep.h>
> > > +#define MEMCHR __memchr
> > >
> > > -#ifdef USE_AS_WMEMCHR
> > > -# define MEMCHR                wmemchr
> > > -# define PCMPEQ                pcmpeqd
> > > -# define CHAR_PER_VEC  4
> > > -#else
> > > -# define MEMCHR                memchr
> > > -# define PCMPEQ                pcmpeqb
> > > -# define CHAR_PER_VEC  16
> > > -#endif
> > > +#define DEFAULT_IMPL_V1        "multiarch/memchr-sse2.S"
> > > +#define DEFAULT_IMPL_V3        "multiarch/memchr-avx2.S"
> > > +#define DEFAULT_IMPL_V4        "multiarch/memchr-evex.S"
> > >
> > > -/* fast SSE2 version with using pmaxub and 64 byte loop */
> > > +#include "isa-default-impl.h"
> > >
> > > -       .text
> > > -ENTRY(MEMCHR)
> > > -       movd    %esi, %xmm1
> > > -       mov     %edi, %ecx
> > > -
> > > -#ifdef __ILP32__
> > > -       /* Clear the upper 32 bits.  */
> > > -       movl    %edx, %edx
> > > -#endif
> > > -#ifdef USE_AS_WMEMCHR
> > > -       test    %RDX_LP, %RDX_LP
> > > -       jz      L(return_null)
> > > -#else
> > > -       punpcklbw %xmm1, %xmm1
> > > -       test    %RDX_LP, %RDX_LP
> > > -       jz      L(return_null)
> > > -       punpcklbw %xmm1, %xmm1
> > > -#endif
> > > -
> > > -       and     $63, %ecx
> > > -       pshufd  $0, %xmm1, %xmm1
> > > -
> > > -       cmp     $48, %ecx
> > > -       ja      L(crosscache)
> > > -
> > > -       movdqu  (%rdi), %xmm0
> > > -       PCMPEQ  %xmm1, %xmm0
> > > -       pmovmskb %xmm0, %eax
> > > -       test    %eax, %eax
> > > -
> > > -       jnz     L(matches_1)
> > > -       sub     $CHAR_PER_VEC, %rdx
> > > -       jbe     L(return_null)
> > > -       add     $16, %rdi
> > > -       and     $15, %ecx
> > > -       and     $-16, %rdi
> > > -#ifdef USE_AS_WMEMCHR
> > > -       shr     $2, %ecx
> > > -#endif
> > > -       add     %rcx, %rdx
> > > -       sub     $(CHAR_PER_VEC * 4), %rdx
> > > -       jbe     L(exit_loop)
> > > -       jmp     L(loop_prolog)
> > > -
> > > -       .p2align 4
> > > -L(crosscache):
> > > -       and     $15, %ecx
> > > -       and     $-16, %rdi
> > > -       movdqa  (%rdi), %xmm0
> > > -
> > > -       PCMPEQ  %xmm1, %xmm0
> > > -       /* Check if there is a match.  */
> > > -       pmovmskb %xmm0, %eax
> > > -       /* Remove the leading bytes.  */
> > > -       sar     %cl, %eax
> > > -       test    %eax, %eax
> > > -       je      L(unaligned_no_match)
> > > -       /* Check which byte is a match.  */
> > > -       bsf     %eax, %eax
> > > -#ifdef USE_AS_WMEMCHR
> > > -       mov     %eax, %esi
> > > -       shr     $2, %esi
> > > -       sub     %rsi, %rdx
> > > -#else
> > > -       sub     %rax, %rdx
> > > -#endif
> > > -       jbe     L(return_null)
> > > -       add     %rdi, %rax
> > > -       add     %rcx, %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(unaligned_no_match):
> > > -       /* "rcx" is less than 16.  Calculate "rdx + rcx - 16" by using
> > > -          "rdx - (16 - rcx)" instead of "(rdx + rcx) - 16" to void
> > > -          possible addition overflow.  */
> > > -       neg     %rcx
> > > -       add     $16, %rcx
> > > -#ifdef USE_AS_WMEMCHR
> > > -       shr     $2, %ecx
> > > -#endif
> > > -       sub     %rcx, %rdx
> > > -       jbe     L(return_null)
> > > -       add     $16, %rdi
> > > -       sub     $(CHAR_PER_VEC * 4), %rdx
> > > -       jbe     L(exit_loop)
> > > -
> > > -       .p2align 4
> > > -L(loop_prolog):
> > > -       movdqa  (%rdi), %xmm0
> > > -       PCMPEQ  %xmm1, %xmm0
> > > -       pmovmskb %xmm0, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches)
> > > -
> > > -       movdqa  16(%rdi), %xmm2
> > > -       PCMPEQ  %xmm1, %xmm2
> > > -       pmovmskb %xmm2, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches16)
> > > -
> > > -       movdqa  32(%rdi), %xmm3
> > > -       PCMPEQ  %xmm1, %xmm3
> > > -       pmovmskb %xmm3, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches32)
> > > -
> > > -       movdqa  48(%rdi), %xmm4
> > > -       PCMPEQ  %xmm1, %xmm4
> > > -       add     $64, %rdi
> > > -       pmovmskb %xmm4, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches0)
> > > -
> > > -       test    $0x3f, %rdi
> > > -       jz      L(align64_loop)
> > > -
> > > -       sub     $(CHAR_PER_VEC * 4), %rdx
> > > -       jbe     L(exit_loop)
> > > -
> > > -       movdqa  (%rdi), %xmm0
> > > -       PCMPEQ  %xmm1, %xmm0
> > > -       pmovmskb %xmm0, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches)
> > > -
> > > -       movdqa  16(%rdi), %xmm2
> > > -       PCMPEQ  %xmm1, %xmm2
> > > -       pmovmskb %xmm2, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches16)
> > > -
> > > -       movdqa  32(%rdi), %xmm3
> > > -       PCMPEQ  %xmm1, %xmm3
> > > -       pmovmskb %xmm3, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches32)
> > > -
> > > -       movdqa  48(%rdi), %xmm3
> > > -       PCMPEQ  %xmm1, %xmm3
> > > -       pmovmskb %xmm3, %eax
> > > -
> > > -       add     $64, %rdi
> > > -       test    %eax, %eax
> > > -       jnz     L(matches0)
> > > -
> > > -       mov     %rdi, %rcx
> > > -       and     $-64, %rdi
> > > -       and     $63, %ecx
> > > -#ifdef USE_AS_WMEMCHR
> > > -       shr     $2, %ecx
> > > -#endif
> > > -       add     %rcx, %rdx
> > > -
> > > -       .p2align 4
> > > -L(align64_loop):
> > > -       sub     $(CHAR_PER_VEC * 4), %rdx
> > > -       jbe     L(exit_loop)
> > > -       movdqa  (%rdi), %xmm0
> > > -       movdqa  16(%rdi), %xmm2
> > > -       movdqa  32(%rdi), %xmm3
> > > -       movdqa  48(%rdi), %xmm4
> > > -
> > > -       PCMPEQ  %xmm1, %xmm0
> > > -       PCMPEQ  %xmm1, %xmm2
> > > -       PCMPEQ  %xmm1, %xmm3
> > > -       PCMPEQ  %xmm1, %xmm4
> > > -
> > > -       pmaxub  %xmm0, %xmm3
> > > -       pmaxub  %xmm2, %xmm4
> > > -       pmaxub  %xmm3, %xmm4
> > > -       pmovmskb %xmm4, %eax
> > > -
> > > -       add     $64, %rdi
> > > -
> > > -       test    %eax, %eax
> > > -       jz      L(align64_loop)
> > > -
> > > -       sub     $64, %rdi
> > > -
> > > -       pmovmskb %xmm0, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches)
> > > -
> > > -       pmovmskb %xmm2, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches16)
> > > -
> > > -       movdqa  32(%rdi), %xmm3
> > > -       PCMPEQ  %xmm1, %xmm3
> > > -
> > > -       PCMPEQ  48(%rdi), %xmm1
> > > -       pmovmskb %xmm3, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches32)
> > > -
> > > -       pmovmskb %xmm1, %eax
> > > -       bsf     %eax, %eax
> > > -       lea     48(%rdi, %rax), %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(exit_loop):
> > > -       add     $(CHAR_PER_VEC * 2), %edx
> > > -       jle     L(exit_loop_32)
> > > -
> > > -       movdqa  (%rdi), %xmm0
> > > -       PCMPEQ  %xmm1, %xmm0
> > > -       pmovmskb %xmm0, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches)
> > > -
> > > -       movdqa  16(%rdi), %xmm2
> > > -       PCMPEQ  %xmm1, %xmm2
> > > -       pmovmskb %xmm2, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches16)
> > > -
> > > -       movdqa  32(%rdi), %xmm3
> > > -       PCMPEQ  %xmm1, %xmm3
> > > -       pmovmskb %xmm3, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches32_1)
> > > -       sub     $CHAR_PER_VEC, %edx
> > > -       jle     L(return_null)
> > > -
> > > -       PCMPEQ  48(%rdi), %xmm1
> > > -       pmovmskb %xmm1, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches48_1)
> > > -       xor     %eax, %eax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(exit_loop_32):
> > > -       add     $(CHAR_PER_VEC * 2), %edx
> > > -       movdqa  (%rdi), %xmm0
> > > -       PCMPEQ  %xmm1, %xmm0
> > > -       pmovmskb %xmm0, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches_1)
> > > -       sub     $CHAR_PER_VEC, %edx
> > > -       jbe     L(return_null)
> > > -
> > > -       PCMPEQ  16(%rdi), %xmm1
> > > -       pmovmskb %xmm1, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches16_1)
> > > -       xor     %eax, %eax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(matches0):
> > > -       bsf     %eax, %eax
> > > -       lea     -16(%rax, %rdi), %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(matches):
> > > -       bsf     %eax, %eax
> > > -       add     %rdi, %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(matches16):
> > > -       bsf     %eax, %eax
> > > -       lea     16(%rax, %rdi), %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(matches32):
> > > -       bsf     %eax, %eax
> > > -       lea     32(%rax, %rdi), %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(matches_1):
> > > -       bsf     %eax, %eax
> > > -#ifdef USE_AS_WMEMCHR
> > > -       mov     %eax, %esi
> > > -       shr     $2, %esi
> > > -       sub     %rsi, %rdx
> > > -#else
> > > -       sub     %rax, %rdx
> > > -#endif
> > > -       jbe     L(return_null)
> > > -       add     %rdi, %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(matches16_1):
> > > -       bsf     %eax, %eax
> > > -#ifdef USE_AS_WMEMCHR
> > > -       mov     %eax, %esi
> > > -       shr     $2, %esi
> > > -       sub     %rsi, %rdx
> > > -#else
> > > -       sub     %rax, %rdx
> > > -#endif
> > > -       jbe     L(return_null)
> > > -       lea     16(%rdi, %rax), %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(matches32_1):
> > > -       bsf     %eax, %eax
> > > -#ifdef USE_AS_WMEMCHR
> > > -       mov     %eax, %esi
> > > -       shr     $2, %esi
> > > -       sub     %rsi, %rdx
> > > -#else
> > > -       sub     %rax, %rdx
> > > -#endif
> > > -       jbe     L(return_null)
> > > -       lea     32(%rdi, %rax), %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(matches48_1):
> > > -       bsf     %eax, %eax
> > > -#ifdef USE_AS_WMEMCHR
> > > -       mov     %eax, %esi
> > > -       shr     $2, %esi
> > > -       sub     %rsi, %rdx
> > > -#else
> > > -       sub     %rax, %rdx
> > > -#endif
> > > -       jbe     L(return_null)
> > > -       lea     48(%rdi, %rax), %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(return_null):
> > > -       xor     %eax, %eax
> > > -       ret
> > > -END(MEMCHR)
> > > -
> > > -#ifndef USE_AS_WMEMCHR
> > > -strong_alias (memchr, __memchr)
> > > +weak_alias (__memchr, memchr)
> > >  libc_hidden_builtin_def(memchr)
> > > -#endif
> > > diff --git a/sysdeps/x86_64/multiarch/ifunc-evex.h b/sysdeps/x86_64/multiarch/ifunc-evex.h
> > > index b8f7a12ea2..856c6261f8 100644
> > > --- a/sysdeps/x86_64/multiarch/ifunc-evex.h
> > > +++ b/sysdeps/x86_64/multiarch/ifunc-evex.h
> > > @@ -19,24 +19,28 @@
> > >
> > >  #include <init-arch.h>
> > >
> > > -extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
> > > -extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
> > > -extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
> > >  extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
> > >  extern __typeof (REDIRECT_NAME) OPTIMIZE (evex_rtm) attribute_hidden;
> > >
> > > +extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
> > > +extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
> > > +
> > > +extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
> > >
> > >  static inline void *
> > >  IFUNC_SELECTOR (void)
> > >  {
> > > -  const struct cpu_features* cpu_features = __get_cpu_features ();
> > > -
> > > -  if (CPU_FEATURE_USABLE_P (cpu_features, AVX2)
> > > -      && CPU_FEATURE_USABLE_P (cpu_features, BMI2)
> > > -      && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
> > > +  const struct cpu_features *cpu_features = __get_cpu_features ();
> > > +
> > > +  /* NB: The X86_ISA_* feature check macros are evaluated at
> > > +     compile time.  */
> > > +  if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX2)
> > > +      && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, BMI2)
> > > +      && X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
> > > +                                     AVX_Fast_Unaligned_Load))
> > >      {
> > > -      if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
> > > -         && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
> > > +      if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
> > > +         && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
> > >         {
> > >           if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
> > >             return OPTIMIZE (evex_rtm);
> > > @@ -47,9 +51,12 @@ IFUNC_SELECTOR (void)
> > >        if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
> > >         return OPTIMIZE (avx2_rtm);
> > >
> > > -      if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
> > > +      if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
> > > +                                      Prefer_No_VZEROUPPER))
> > >         return OPTIMIZE (avx2);
> > >      }
> > >
> > > +  /* This is unreachable (compile time checked) if ISA level >= 3
> > > +     so no need for a robust fallback here.  */
> > >    return OPTIMIZE (sse2);
> > >  }
> > > diff --git a/sysdeps/x86_64/multiarch/ifunc-impl-list.c b/sysdeps/x86_64/multiarch/ifunc-impl-list.c
> > > index 883362f63d..bf52cf96d0 100644
> > > --- a/sysdeps/x86_64/multiarch/ifunc-impl-list.c
> > > +++ b/sysdeps/x86_64/multiarch/ifunc-impl-list.c
> > > @@ -25,7 +25,8 @@
> > >
> > >  /* Fill ARRAY of MAX elements with IFUNC implementations for function
> > >     NAME supported on target machine and return the number of valid
> > > -   entries.  */
> > > +   entries.  Each set of implementations for a given function is sorted in
> > > +   descending order by ISA level.  */
> > >
> > >  size_t
> > >  __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
> > > @@ -53,24 +54,27 @@ __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),
> > > -                             __memchr_avx2)
> > > -             IFUNC_IMPL_ADD (array, i, memchr,
> > > -                             (CPU_FEATURE_USABLE (AVX2)
> > > -                              && CPU_FEATURE_USABLE (RTM)),
> > > -                             __memchr_avx2_rtm)
> > > -             IFUNC_IMPL_ADD (array, i, memchr,
> > > +             X86_IFUNC_IMPL_ADD_V4 (array, i, memchr,
> > >                               (CPU_FEATURE_USABLE (AVX512VL)
> > >                                && CPU_FEATURE_USABLE (AVX512BW)
> > >                                && CPU_FEATURE_USABLE (BMI2)),
> > >                               __memchr_evex)
> > > -             IFUNC_IMPL_ADD (array, i, memchr,
> > > +             X86_IFUNC_IMPL_ADD_V4 (array, i, memchr,
> > >                               (CPU_FEATURE_USABLE (AVX512VL)
> > >                                && CPU_FEATURE_USABLE (AVX512BW)
> > >                                && CPU_FEATURE_USABLE (BMI2)),
> > >                               __memchr_evex_rtm)
> > > -             IFUNC_IMPL_ADD (array, i, memchr, 1, __memchr_sse2))
> > > +             X86_IFUNC_IMPL_ADD_V3 (array, i, memchr,
> > > +                             CPU_FEATURE_USABLE (AVX2),
> > > +                             __memchr_avx2)
> > > +             X86_IFUNC_IMPL_ADD_V3 (array, i, memchr,
> > > +                             (CPU_FEATURE_USABLE (AVX2)
> > > +                              && CPU_FEATURE_USABLE (RTM)),
> > > +                             __memchr_avx2_rtm)
> > > +             /* Can be lowered to V1 if a V2 implementation is added.  */
> > > +             X86_IFUNC_IMPL_ADD_V2 (array, i, memchr,
> > > +                             1,
> > > +                             __memchr_sse2))
> > >
> > >    /* Support sysdeps/x86_64/multiarch/memcmp.c.  */
> > >    IFUNC_IMPL (i, name, memcmp,
> > > @@ -288,24 +292,27 @@ __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),
> > > -                             __rawmemchr_avx2)
> > > -             IFUNC_IMPL_ADD (array, i, rawmemchr,
> > > -                             (CPU_FEATURE_USABLE (AVX2)
> > > -                              && CPU_FEATURE_USABLE (RTM)),
> > > -                             __rawmemchr_avx2_rtm)
> > > -             IFUNC_IMPL_ADD (array, i, rawmemchr,
> > > +             X86_IFUNC_IMPL_ADD_V4 (array, i, rawmemchr,
> > >                               (CPU_FEATURE_USABLE (AVX512VL)
> > >                                && CPU_FEATURE_USABLE (AVX512BW)
> > >                                && CPU_FEATURE_USABLE (BMI2)),
> > >                               __rawmemchr_evex)
> > > -             IFUNC_IMPL_ADD (array, i, rawmemchr,
> > > +             X86_IFUNC_IMPL_ADD_V4 (array, i, rawmemchr,
> > >                               (CPU_FEATURE_USABLE (AVX512VL)
> > >                                && CPU_FEATURE_USABLE (AVX512BW)
> > >                                && CPU_FEATURE_USABLE (BMI2)),
> > >                               __rawmemchr_evex_rtm)
> > > -             IFUNC_IMPL_ADD (array, i, rawmemchr, 1, __rawmemchr_sse2))
> > > +             X86_IFUNC_IMPL_ADD_V3 (array, i, rawmemchr,
> > > +                             CPU_FEATURE_USABLE (AVX2),
> > > +                             __rawmemchr_avx2)
> > > +             X86_IFUNC_IMPL_ADD_V3 (array, i, rawmemchr,
> > > +                             (CPU_FEATURE_USABLE (AVX2)
> > > +                              && CPU_FEATURE_USABLE (RTM)),
> > > +                             __rawmemchr_avx2_rtm)
> > > +             /* Can be lowered to V1 if a V2 implementation is added.  */
> > > +             X86_IFUNC_IMPL_ADD_V2 (array, i, rawmemchr,
> > > +                             1,
> > > +                             __rawmemchr_sse2))
> > >
> > >    /* Support sysdeps/x86_64/multiarch/strlen.c.  */
> > >    IFUNC_IMPL (i, name, strlen,
> > > @@ -748,24 +755,27 @@ __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),
> > > -                             __wmemchr_avx2)
> > > -             IFUNC_IMPL_ADD (array, i, wmemchr,
> > > -                             (CPU_FEATURE_USABLE (AVX2)
> > > -                              && CPU_FEATURE_USABLE (RTM)),
> > > -                             __wmemchr_avx2_rtm)
> > > -             IFUNC_IMPL_ADD (array, i, wmemchr,
> > > +             X86_IFUNC_IMPL_ADD_V4 (array, i, wmemchr,
> > >                               (CPU_FEATURE_USABLE (AVX512VL)
> > >                                && CPU_FEATURE_USABLE (AVX512BW)
> > >                                && CPU_FEATURE_USABLE (BMI2)),
> > >                               __wmemchr_evex)
> > > -             IFUNC_IMPL_ADD (array, i, wmemchr,
> > > +             X86_IFUNC_IMPL_ADD_V4 (array, i, wmemchr,
> > >                               (CPU_FEATURE_USABLE (AVX512VL)
> > >                                && CPU_FEATURE_USABLE (AVX512BW)
> > >                                && CPU_FEATURE_USABLE (BMI2)),
> > >                               __wmemchr_evex_rtm)
> > > -             IFUNC_IMPL_ADD (array, i, wmemchr, 1, __wmemchr_sse2))
> > > +             X86_IFUNC_IMPL_ADD_V3 (array, i, wmemchr,
> > > +                             CPU_FEATURE_USABLE (AVX2),
> > > +                             __wmemchr_avx2)
> > > +             X86_IFUNC_IMPL_ADD_V3 (array, i, wmemchr,
> > > +                             (CPU_FEATURE_USABLE (AVX2)
> > > +                              && CPU_FEATURE_USABLE (RTM)),
> > > +                             __wmemchr_avx2_rtm)
> > > +             /* Can be lowered to V1 if a V2 implementation is added.  */
> > > +             X86_IFUNC_IMPL_ADD_V2 (array, i, wmemchr,
> > > +                             1,
> > > +                             __wmemchr_sse2))
> > >
> > >    /* Support sysdeps/x86_64/multiarch/wmemcmp.c.  */
> > >    IFUNC_IMPL (i, name, wmemcmp,
> > > diff --git a/sysdeps/x86_64/multiarch/memchr-avx2.S b/sysdeps/x86_64/multiarch/memchr-avx2.S
> > > index c5a256eb37..39be5f7083 100644
> > > --- a/sysdeps/x86_64/multiarch/memchr-avx2.S
> > > +++ b/sysdeps/x86_64/multiarch/memchr-avx2.S
> > > @@ -16,9 +16,10 @@
> > >     License along with the GNU C Library; if not, see
> > >     <https://www.gnu.org/licenses/>.  */
> > >
> > > -#if IS_IN (libc)
> > > +#include <isa-level.h>
> > > +#include <sysdep.h>
> > >
> > > -# include <sysdep.h>
> > > +#if ISA_SHOULD_BUILD (3)
> > >
> > >  # ifndef MEMCHR
> > >  #  define MEMCHR       __memchr_avx2
> > > diff --git a/sysdeps/x86_64/multiarch/memchr-evex.S b/sysdeps/x86_64/multiarch/memchr-evex.S
> > > index 0fd11b7632..0dd4f1dcce 100644
> > > --- a/sysdeps/x86_64/multiarch/memchr-evex.S
> > > +++ b/sysdeps/x86_64/multiarch/memchr-evex.S
> > > @@ -16,9 +16,10 @@
> > >     License along with the GNU C Library; if not, see
> > >     <https://www.gnu.org/licenses/>.  */
> > >
> > > -#if IS_IN (libc)
> > > +#include <isa-level.h>
> > > +#include <sysdep.h>
> > >
> > > -# include <sysdep.h>
> > > +#if ISA_SHOULD_BUILD (4)
> > >
> > >  # ifndef MEMCHR
> > >  #  define MEMCHR       __memchr_evex
> > > diff --git a/sysdeps/x86_64/multiarch/memchr-sse2.S b/sysdeps/x86_64/multiarch/memchr-sse2.S
> > > index 2c6fdd41d6..8c561cd687 100644
> > > --- a/sysdeps/x86_64/multiarch/memchr-sse2.S
> > > +++ b/sysdeps/x86_64/multiarch/memchr-sse2.S
> > > @@ -16,13 +16,360 @@
> > >     License along with the GNU C Library; if not, see
> > >     <https://www.gnu.org/licenses/>.  */
> > >
> > > -#if IS_IN (libc)
> > > -# define memchr __memchr_sse2
> > > +#include <isa-level.h>
> > > +#include <sysdep.h>
> > >
> > > -# undef strong_alias
> > > -# define strong_alias(memchr, __memchr)
> > > -# undef libc_hidden_builtin_def
> > > -# define libc_hidden_builtin_def(memchr)
> > > -#endif
> > > +/* MINIMUM_X86_ISA_LEVEL <= 2 because there is no V2 implementation
> > > +   so we need this to build for ISA V2 builds. */
> > > +#if ISA_SHOULD_BUILD (2)
> > > +
> > > +# ifndef MEMCHR
> > > +#  define MEMCHR       __memchr_sse2
> > > +# endif
> > > +# ifdef USE_AS_WMEMCHR
> > > +#  define PCMPEQ               pcmpeqd
> > > +#  define CHAR_PER_VEC 4
> > > +# else
> > > +#  define PCMPEQ               pcmpeqb
> > > +#  define CHAR_PER_VEC 16
> > > +# endif
> > > +
> > > +/* fast SSE2 version with using pmaxub and 64 byte loop */
> > > +
> > > +       .text
> > > +ENTRY(MEMCHR)
> > > +       movd    %esi, %xmm1
> > > +       mov     %edi, %ecx
> > > +
> > > +# ifdef __ILP32__
> > > +       /* Clear the upper 32 bits.  */
> > > +       movl    %edx, %edx
> > > +# endif
> > > +# ifdef USE_AS_WMEMCHR
> > > +       test    %RDX_LP, %RDX_LP
> > > +       jz      L(return_null)
> > > +# else
> > > +       punpcklbw %xmm1, %xmm1
> > > +       test    %RDX_LP, %RDX_LP
> > > +       jz      L(return_null)
> > > +       punpcklbw %xmm1, %xmm1
> > > +# endif
> > > +
> > > +       and     $63, %ecx
> > > +       pshufd  $0, %xmm1, %xmm1
> > > +
> > > +       cmp     $48, %ecx
> > > +       ja      L(crosscache)
> > > +
> > > +       movdqu  (%rdi), %xmm0
> > > +       PCMPEQ  %xmm1, %xmm0
> > > +       pmovmskb %xmm0, %eax
> > > +       test    %eax, %eax
> > > +
> > > +       jnz     L(matches_1)
> > > +       sub     $CHAR_PER_VEC, %rdx
> > > +       jbe     L(return_null)
> > > +       add     $16, %rdi
> > > +       and     $15, %ecx
> > > +       and     $-16, %rdi
> > > +# ifdef USE_AS_WMEMCHR
> > > +       shr     $2, %ecx
> > > +# endif
> > > +       add     %rcx, %rdx
> > > +       sub     $(CHAR_PER_VEC * 4), %rdx
> > > +       jbe     L(exit_loop)
> > > +       jmp     L(loop_prolog)
> > > +
> > > +       .p2align 4
> > > +L(crosscache):
> > > +       and     $15, %ecx
> > > +       and     $-16, %rdi
> > > +       movdqa  (%rdi), %xmm0
> > > +
> > > +       PCMPEQ  %xmm1, %xmm0
> > > +       /* Check if there is a match.  */
> > > +       pmovmskb %xmm0, %eax
> > > +       /* Remove the leading bytes.  */
> > > +       sar     %cl, %eax
> > > +       test    %eax, %eax
> > > +       je      L(unaligned_no_match)
> > > +       /* Check which byte is a match.  */
> > > +       bsf     %eax, %eax
> > > +# ifdef USE_AS_WMEMCHR
> > > +       mov     %eax, %esi
> > > +       shr     $2, %esi
> > > +       sub     %rsi, %rdx
> > > +# else
> > > +       sub     %rax, %rdx
> > > +# endif
> > > +       jbe     L(return_null)
> > > +       add     %rdi, %rax
> > > +       add     %rcx, %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(unaligned_no_match):
> > > +       /* "rcx" is less than 16.  Calculate "rdx + rcx - 16" by using
> > > +          "rdx - (16 - rcx)" instead of "(rdx + rcx) - 16" to void
> > > +          possible addition overflow.  */
> > > +       neg     %rcx
> > > +       add     $16, %rcx
> > > +# ifdef USE_AS_WMEMCHR
> > > +       shr     $2, %ecx
> > > +# endif
> > > +       sub     %rcx, %rdx
> > > +       jbe     L(return_null)
> > > +       add     $16, %rdi
> > > +       sub     $(CHAR_PER_VEC * 4), %rdx
> > > +       jbe     L(exit_loop)
> > > +
> > > +       .p2align 4
> > > +L(loop_prolog):
> > > +       movdqa  (%rdi), %xmm0
> > > +       PCMPEQ  %xmm1, %xmm0
> > > +       pmovmskb %xmm0, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches)
> > > +
> > > +       movdqa  16(%rdi), %xmm2
> > > +       PCMPEQ  %xmm1, %xmm2
> > > +       pmovmskb %xmm2, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches16)
> > > +
> > > +       movdqa  32(%rdi), %xmm3
> > > +       PCMPEQ  %xmm1, %xmm3
> > > +       pmovmskb %xmm3, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches32)
> > > +
> > > +       movdqa  48(%rdi), %xmm4
> > > +       PCMPEQ  %xmm1, %xmm4
> > > +       add     $64, %rdi
> > > +       pmovmskb %xmm4, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches0)
> > > +
> > > +       test    $0x3f, %rdi
> > > +       jz      L(align64_loop)
> > > +
> > > +       sub     $(CHAR_PER_VEC * 4), %rdx
> > > +       jbe     L(exit_loop)
> > > +
> > > +       movdqa  (%rdi), %xmm0
> > > +       PCMPEQ  %xmm1, %xmm0
> > > +       pmovmskb %xmm0, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches)
> > > +
> > > +       movdqa  16(%rdi), %xmm2
> > > +       PCMPEQ  %xmm1, %xmm2
> > > +       pmovmskb %xmm2, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches16)
> > > +
> > > +       movdqa  32(%rdi), %xmm3
> > > +       PCMPEQ  %xmm1, %xmm3
> > > +       pmovmskb %xmm3, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches32)
> > > +
> > > +       movdqa  48(%rdi), %xmm3
> > > +       PCMPEQ  %xmm1, %xmm3
> > > +       pmovmskb %xmm3, %eax
> > > +
> > > +       add     $64, %rdi
> > > +       test    %eax, %eax
> > > +       jnz     L(matches0)
> > > +
> > > +       mov     %rdi, %rcx
> > > +       and     $-64, %rdi
> > > +       and     $63, %ecx
> > > +# ifdef USE_AS_WMEMCHR
> > > +       shr     $2, %ecx
> > > +# endif
> > > +       add     %rcx, %rdx
> > > +
> > > +       .p2align 4
> > > +L(align64_loop):
> > > +       sub     $(CHAR_PER_VEC * 4), %rdx
> > > +       jbe     L(exit_loop)
> > > +       movdqa  (%rdi), %xmm0
> > > +       movdqa  16(%rdi), %xmm2
> > > +       movdqa  32(%rdi), %xmm3
> > > +       movdqa  48(%rdi), %xmm4
> > > +
> > > +       PCMPEQ  %xmm1, %xmm0
> > > +       PCMPEQ  %xmm1, %xmm2
> > > +       PCMPEQ  %xmm1, %xmm3
> > > +       PCMPEQ  %xmm1, %xmm4
> > >
> > > -#include "../memchr.S"
> > > +       pmaxub  %xmm0, %xmm3
> > > +       pmaxub  %xmm2, %xmm4
> > > +       pmaxub  %xmm3, %xmm4
> > > +       pmovmskb %xmm4, %eax
> > > +
> > > +       add     $64, %rdi
> > > +
> > > +       test    %eax, %eax
> > > +       jz      L(align64_loop)
> > > +
> > > +       sub     $64, %rdi
> > > +
> > > +       pmovmskb %xmm0, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches)
> > > +
> > > +       pmovmskb %xmm2, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches16)
> > > +
> > > +       movdqa  32(%rdi), %xmm3
> > > +       PCMPEQ  %xmm1, %xmm3
> > > +
> > > +       PCMPEQ  48(%rdi), %xmm1
> > > +       pmovmskb %xmm3, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches32)
> > > +
> > > +       pmovmskb %xmm1, %eax
> > > +       bsf     %eax, %eax
> > > +       lea     48(%rdi, %rax), %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(exit_loop):
> > > +       add     $(CHAR_PER_VEC * 2), %edx
> > > +       jle     L(exit_loop_32)
> > > +
> > > +       movdqa  (%rdi), %xmm0
> > > +       PCMPEQ  %xmm1, %xmm0
> > > +       pmovmskb %xmm0, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches)
> > > +
> > > +       movdqa  16(%rdi), %xmm2
> > > +       PCMPEQ  %xmm1, %xmm2
> > > +       pmovmskb %xmm2, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches16)
> > > +
> > > +       movdqa  32(%rdi), %xmm3
> > > +       PCMPEQ  %xmm1, %xmm3
> > > +       pmovmskb %xmm3, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches32_1)
> > > +       sub     $CHAR_PER_VEC, %edx
> > > +       jle     L(return_null)
> > > +
> > > +       PCMPEQ  48(%rdi), %xmm1
> > > +       pmovmskb %xmm1, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches48_1)
> > > +       xor     %eax, %eax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(exit_loop_32):
> > > +       add     $(CHAR_PER_VEC * 2), %edx
> > > +       movdqa  (%rdi), %xmm0
> > > +       PCMPEQ  %xmm1, %xmm0
> > > +       pmovmskb %xmm0, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches_1)
> > > +       sub     $CHAR_PER_VEC, %edx
> > > +       jbe     L(return_null)
> > > +
> > > +       PCMPEQ  16(%rdi), %xmm1
> > > +       pmovmskb %xmm1, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches16_1)
> > > +       xor     %eax, %eax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(matches0):
> > > +       bsf     %eax, %eax
> > > +       lea     -16(%rax, %rdi), %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(matches):
> > > +       bsf     %eax, %eax
> > > +       add     %rdi, %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(matches16):
> > > +       bsf     %eax, %eax
> > > +       lea     16(%rax, %rdi), %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(matches32):
> > > +       bsf     %eax, %eax
> > > +       lea     32(%rax, %rdi), %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(matches_1):
> > > +       bsf     %eax, %eax
> > > +# ifdef USE_AS_WMEMCHR
> > > +       mov     %eax, %esi
> > > +       shr     $2, %esi
> > > +       sub     %rsi, %rdx
> > > +# else
> > > +       sub     %rax, %rdx
> > > +# endif
> > > +       jbe     L(return_null)
> > > +       add     %rdi, %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(matches16_1):
> > > +       bsf     %eax, %eax
> > > +# ifdef USE_AS_WMEMCHR
> > > +       mov     %eax, %esi
> > > +       shr     $2, %esi
> > > +       sub     %rsi, %rdx
> > > +# else
> > > +       sub     %rax, %rdx
> > > +# endif
> > > +       jbe     L(return_null)
> > > +       lea     16(%rdi, %rax), %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(matches32_1):
> > > +       bsf     %eax, %eax
> > > +# ifdef USE_AS_WMEMCHR
> > > +       mov     %eax, %esi
> > > +       shr     $2, %esi
> > > +       sub     %rsi, %rdx
> > > +# else
> > > +       sub     %rax, %rdx
> > > +# endif
> > > +       jbe     L(return_null)
> > > +       lea     32(%rdi, %rax), %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(matches48_1):
> > > +       bsf     %eax, %eax
> > > +# ifdef USE_AS_WMEMCHR
> > > +       mov     %eax, %esi
> > > +       shr     $2, %esi
> > > +       sub     %rsi, %rdx
> > > +# else
> > > +       sub     %rax, %rdx
> > > +# endif
> > > +       jbe     L(return_null)
> > > +       lea     48(%rdi, %rax), %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(return_null):
> > > +       xor     %eax, %eax
> > > +       ret
> > > +END(MEMCHR)
> > > +#endif
> > > diff --git a/sysdeps/x86_64/multiarch/rawmemchr-avx2-rtm.S b/sysdeps/x86_64/multiarch/rawmemchr-avx2-rtm.S
> > > index acc5f6e2fb..5c1dcd3ca7 100644
> > > --- a/sysdeps/x86_64/multiarch/rawmemchr-avx2-rtm.S
> > > +++ b/sysdeps/x86_64/multiarch/rawmemchr-avx2-rtm.S
> > > @@ -1,4 +1,7 @@
> > > -#define MEMCHR __rawmemchr_avx2_rtm
> > > -#define USE_AS_RAWMEMCHR 1
> > > +#ifndef RAWMEMCHR
> > > +# define RAWMEMCHR     __rawmemchr_avx2_rtm
> > > +#endif
> > > +#define USE_AS_RAWMEMCHR       1
> > > +#define MEMCHR RAWMEMCHR
> > >
> > >  #include "memchr-avx2-rtm.S"
> >
> > Will we ever use the RTM version as the default?
>
> We had talked about it and agreed not to. I think we can
> safely say we don't need it for the RTLD default because
> we know no transactions.
>
> As for the non-multiarch build selection it's a bit more ambiguous.

Since the RTM version isn't used for default, we should
leave the RTM .S files alone.

> >
> > > diff --git a/sysdeps/x86_64/multiarch/rawmemchr-avx2.S b/sysdeps/x86_64/multiarch/rawmemchr-avx2.S
> > > index 128f9ea637..d6bff28757 100644
> > > --- a/sysdeps/x86_64/multiarch/rawmemchr-avx2.S
> > > +++ b/sysdeps/x86_64/multiarch/rawmemchr-avx2.S
> > > @@ -1,4 +1,7 @@
> > > -#define MEMCHR __rawmemchr_avx2
> > > -#define USE_AS_RAWMEMCHR 1
> > > +#ifndef RAWMEMCHR
> > > +# define RAWMEMCHR     __rawmemchr_avx2
> > > +#endif
> > > +#define USE_AS_RAWMEMCHR       1
> > > +#define MEMCHR RAWMEMCHR
> > >
> > >  #include "memchr-avx2.S"
> > > diff --git a/sysdeps/x86_64/multiarch/rawmemchr-evex-rtm.S b/sysdeps/x86_64/multiarch/rawmemchr-evex-rtm.S
> > > index deda1ca395..8ff7f27c9c 100644
> > > --- a/sysdeps/x86_64/multiarch/rawmemchr-evex-rtm.S
> > > +++ b/sysdeps/x86_64/multiarch/rawmemchr-evex-rtm.S
> > > @@ -1,3 +1,7 @@
> > > -#define MEMCHR __rawmemchr_evex_rtm
> > > -#define USE_AS_RAWMEMCHR 1
> > > +#ifndef RAWMEMCHR
> > > +# define RAWMEMCHR     __rawmemchr_evex_rtm
> > > +#endif
> > > +#define USE_AS_RAWMEMCHR       1
> > > +#define MEMCHR RAWMEMCHR
> > > +
> >
> > Will we ever use the RTM version as the default?
> >
> > >  #include "memchr-evex-rtm.S"
> > > diff --git a/sysdeps/x86_64/multiarch/rawmemchr-evex.S b/sysdeps/x86_64/multiarch/rawmemchr-evex.S
> > > index ec942b77ba..dc1c450699 100644
> > > --- a/sysdeps/x86_64/multiarch/rawmemchr-evex.S
> > > +++ b/sysdeps/x86_64/multiarch/rawmemchr-evex.S
> > > @@ -1,4 +1,7 @@
> > > -#define MEMCHR __rawmemchr_evex
> > > -#define USE_AS_RAWMEMCHR 1
> > > +#ifndef RAWMEMCHR
> > > +# define RAWMEMCHR     __rawmemchr_evex
> > > +#endif
> > > +#define USE_AS_RAWMEMCHR       1
> > > +#define MEMCHR RAWMEMCHR
> > >
> > >  #include "memchr-evex.S"
> > > diff --git a/sysdeps/x86_64/multiarch/rawmemchr-sse2.S b/sysdeps/x86_64/multiarch/rawmemchr-sse2.S
> > > index 3841c14c34..e2c2e20d85 100644
> > > --- a/sysdeps/x86_64/multiarch/rawmemchr-sse2.S
> > > +++ b/sysdeps/x86_64/multiarch/rawmemchr-sse2.S
> > > @@ -16,14 +16,192 @@
> > >     License along with the GNU C Library; if not, see
> > >     <https://www.gnu.org/licenses/>.  */
> > >
> > > -/* Define multiple versions only for the definition in libc. */
> > > -#if IS_IN (libc)
> > > -# define __rawmemchr __rawmemchr_sse2
> > > -
> > > -# undef weak_alias
> > > -# define weak_alias(__rawmemchr, rawmemchr)
> > > -# undef libc_hidden_def
> > > -# define libc_hidden_def(__rawmemchr)
> > > -#endif
> > > +#include <isa-level.h>
> > > +#include <sysdep.h>
> > > +
> > > +/* MINIMUM_X86_ISA_LEVEL <= 2 because there is no V2 implementation
> > > +   so we need this to build for ISA V2 builds. */
> > > +#if ISA_SHOULD_BUILD (2)
> > > +
> > > +# ifndef RAWMEMCHR
> > > +#  define RAWMEMCHR    __rawmemchr_sse2
> > > +# endif
> > > +
> > > +       .text
> > > +ENTRY (RAWMEMCHR)
> > > +       movd    %rsi, %xmm1
> > > +       mov     %rdi, %rcx
> > > +
> > > +       punpcklbw %xmm1, %xmm1
> > > +       punpcklbw %xmm1, %xmm1
> > > +
> > > +       and     $63, %rcx
> > > +       pshufd  $0, %xmm1, %xmm1
> > > +
> > > +       cmp     $48, %rcx
> > > +       ja      L(crosscache)
> > > +
> > > +       movdqu  (%rdi), %xmm0
> > > +       pcmpeqb %xmm1, %xmm0
> > > +/* Check if there is a match.  */
> > > +       pmovmskb %xmm0, %eax
> > > +       test    %eax, %eax
> > > +
> > > +       jnz     L(matches)
> > > +       add     $16, %rdi
> > > +       and     $-16, %rdi
> > > +       jmp     L(loop_prolog)
> > > +
> > > +       .p2align 4
> > > +L(crosscache):
> > > +       and     $15, %rcx
> > > +       and     $-16, %rdi
> > > +       movdqa  (%rdi), %xmm0
> > > +
> > > +       pcmpeqb %xmm1, %xmm0
> > > +/* Check if there is a match.  */
> > > +       pmovmskb %xmm0, %eax
> > > +/* Remove the leading bytes.  */
> > > +       sar     %cl, %eax
> > > +       test    %eax, %eax
> > > +       je      L(unaligned_no_match)
> > > +/* Check which byte is a match.  */
> > > +       bsf     %eax, %eax
> > > +
> > > +       add     %rdi, %rax
> > > +       add     %rcx, %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(unaligned_no_match):
> > > +       add     $16, %rdi
> > > +
> > > +       .p2align 4
> > > +L(loop_prolog):
> > > +       movdqa  (%rdi), %xmm0
> > > +       pcmpeqb %xmm1, %xmm0
> > > +       pmovmskb %xmm0, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches)
> > > +
> > > +       movdqa  16(%rdi), %xmm2
> > > +       pcmpeqb %xmm1, %xmm2
> > > +       pmovmskb %xmm2, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches16)
> > > +
> > > +       movdqa  32(%rdi), %xmm3
> > > +       pcmpeqb %xmm1, %xmm3
> > > +       pmovmskb %xmm3, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches32)
> > > +
> > > +       movdqa  48(%rdi), %xmm4
> > > +       pcmpeqb %xmm1, %xmm4
> > > +       add     $64, %rdi
> > > +       pmovmskb %xmm4, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches0)
> > > +
> > > +       test    $0x3f, %rdi
> > > +       jz      L(align64_loop)
> > > +
> > > +       movdqa  (%rdi), %xmm0
> > > +       pcmpeqb %xmm1, %xmm0
> > > +       pmovmskb %xmm0, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches)
> > > +
> > > +       movdqa  16(%rdi), %xmm2
> > > +       pcmpeqb %xmm1, %xmm2
> > > +       pmovmskb %xmm2, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches16)
> > >
> > > -#include "../rawmemchr.S"
> > > +       movdqa  32(%rdi), %xmm3
> > > +       pcmpeqb %xmm1, %xmm3
> > > +       pmovmskb %xmm3, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches32)
> > > +
> > > +       movdqa  48(%rdi), %xmm3
> > > +       pcmpeqb %xmm1, %xmm3
> > > +       pmovmskb %xmm3, %eax
> > > +
> > > +       add     $64, %rdi
> > > +       test    %eax, %eax
> > > +       jnz     L(matches0)
> > > +
> > > +       and     $-64, %rdi
> > > +
> > > +       .p2align 4
> > > +L(align64_loop):
> > > +       movdqa  (%rdi), %xmm0
> > > +       movdqa  16(%rdi), %xmm2
> > > +       movdqa  32(%rdi), %xmm3
> > > +       movdqa  48(%rdi), %xmm4
> > > +
> > > +       pcmpeqb %xmm1, %xmm0
> > > +       pcmpeqb %xmm1, %xmm2
> > > +       pcmpeqb %xmm1, %xmm3
> > > +       pcmpeqb %xmm1, %xmm4
> > > +
> > > +       pmaxub  %xmm0, %xmm3
> > > +       pmaxub  %xmm2, %xmm4
> > > +       pmaxub  %xmm3, %xmm4
> > > +       pmovmskb %xmm4, %eax
> > > +
> > > +       add     $64, %rdi
> > > +
> > > +       test    %eax, %eax
> > > +       jz      L(align64_loop)
> > > +
> > > +       sub     $64, %rdi
> > > +
> > > +       pmovmskb %xmm0, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches)
> > > +
> > > +       pmovmskb %xmm2, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches16)
> > > +
> > > +       movdqa  32(%rdi), %xmm3
> > > +       pcmpeqb %xmm1, %xmm3
> > > +
> > > +       pcmpeqb 48(%rdi), %xmm1
> > > +       pmovmskb %xmm3, %eax
> > > +       test    %eax, %eax
> > > +       jnz     L(matches32)
> > > +
> > > +       pmovmskb %xmm1, %eax
> > > +       bsf     %eax, %eax
> > > +       lea     48(%rdi, %rax), %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(matches0):
> > > +       bsf     %eax, %eax
> > > +       lea     -16(%rax, %rdi), %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(matches):
> > > +       bsf     %eax, %eax
> > > +       add     %rdi, %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(matches16):
> > > +       bsf     %eax, %eax
> > > +       lea     16(%rax, %rdi), %rax
> > > +       ret
> > > +
> > > +       .p2align 4
> > > +L(matches32):
> > > +       bsf     %eax, %eax
> > > +       lea     32(%rax, %rdi), %rax
> > > +       ret
> > > +
> > > +END (RAWMEMCHR)
> > > +#endif
> > > diff --git a/sysdeps/x86_64/multiarch/rtld-memchr.S b/sysdeps/x86_64/multiarch/rtld-memchr.S
> > > new file mode 100644
> > > index 0000000000..a14b192bed
> > > --- /dev/null
> > > +++ b/sysdeps/x86_64/multiarch/rtld-memchr.S
> > > @@ -0,0 +1,18 @@
> > > +/* Copyright (C) 2022 Free Software Foundation, Inc.
> > > +   This file is part of the GNU C Library.
> > > +
> > > +   The GNU C Library is free software; you can redistribute it and/or
> > > +   modify it under the terms of the GNU Lesser General Public
> > > +   License as published by the Free Software Foundation; either
> > > +   version 2.1 of the License, or (at your option) any later version.
> > > +
> > > +   The GNU C Library is distributed in the hope that it will be useful,
> > > +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> > > +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> > > +   Lesser General Public License for more details.
> > > +
> > > +   You should have received a copy of the GNU Lesser General Public
> > > +   License along with the GNU C Library; if not, see
> > > +   <https://www.gnu.org/licenses/>.  */
> > > +
> > > +#include "../memchr.S"
> > > diff --git a/sysdeps/x86_64/multiarch/rtld-rawmemchr.S b/sysdeps/x86_64/multiarch/rtld-rawmemchr.S
> > > new file mode 100644
> > > index 0000000000..5d4110a052
> > > --- /dev/null
> > > +++ b/sysdeps/x86_64/multiarch/rtld-rawmemchr.S
> > > @@ -0,0 +1,18 @@
> > > +/* Copyright (C) 2022 Free Software Foundation, Inc.
> > > +   This file is part of the GNU C Library.
> > > +
> > > +   The GNU C Library is free software; you can redistribute it and/or
> > > +   modify it under the terms of the GNU Lesser General Public
> > > +   License as published by the Free Software Foundation; either
> > > +   version 2.1 of the License, or (at your option) any later version.
> > > +
> > > +   The GNU C Library is distributed in the hope that it will be useful,
> > > +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> > > +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> > > +   Lesser General Public License for more details.
> > > +
> > > +   You should have received a copy of the GNU Lesser General Public
> > > +   License along with the GNU C Library; if not, see
> > > +   <https://www.gnu.org/licenses/>.  */
> > > +
> > > +#include "../rawmemchr.S"
> > > diff --git a/sysdeps/x86_64/multiarch/wmemchr-avx2-rtm.S b/sysdeps/x86_64/multiarch/wmemchr-avx2-rtm.S
> > > index 58ed21db01..2a1cff5b05 100644
> > > --- a/sysdeps/x86_64/multiarch/wmemchr-avx2-rtm.S
> > > +++ b/sysdeps/x86_64/multiarch/wmemchr-avx2-rtm.S
> > > @@ -1,4 +1,7 @@
> > > -#define MEMCHR __wmemchr_avx2_rtm
> > > -#define USE_AS_WMEMCHR 1
> > > +#ifndef WMEMCHR
> > > +# define WMEMCHR       __wmemchr_avx2_rtm
> > > +#endif
> > > +#define USE_AS_WMEMCHR 1
> > > +#define MEMCHR WMEMCHR
> > >
> > >  #include "memchr-avx2-rtm.S"
> > > diff --git a/sysdeps/x86_64/multiarch/wmemchr-avx2.S b/sysdeps/x86_64/multiarch/wmemchr-avx2.S
> > > index 282854f1a1..2bf93fd84b 100644
> > > --- a/sysdeps/x86_64/multiarch/wmemchr-avx2.S
> > > +++ b/sysdeps/x86_64/multiarch/wmemchr-avx2.S
> > > @@ -1,4 +1,7 @@
> > > -#define MEMCHR __wmemchr_avx2
> > > -#define USE_AS_WMEMCHR 1
> > > +#ifndef WMEMCHR
> > > +# define WMEMCHR       __wmemchr_avx2
> > > +#endif
> > > +#define USE_AS_WMEMCHR 1
> > > +#define MEMCHR WMEMCHR
> > >
> > >  #include "memchr-avx2.S"
> > > diff --git a/sysdeps/x86_64/multiarch/wmemchr-evex-rtm.S b/sysdeps/x86_64/multiarch/wmemchr-evex-rtm.S
> > > index a346cd35a1..c67309e8a1 100644
> > > --- a/sysdeps/x86_64/multiarch/wmemchr-evex-rtm.S
> > > +++ b/sysdeps/x86_64/multiarch/wmemchr-evex-rtm.S
> > > @@ -1,3 +1,7 @@
> > > -#define MEMCHR __wmemchr_evex_rtm
> > > -#define USE_AS_WMEMCHR 1
> > > +#ifndef WMEMCHR
> > > +# define WMEMCHR       __wmemchr_evex_rtm
> > > +#endif
> > > +#define USE_AS_WMEMCHR 1
> > > +#define MEMCHR WMEMCHR
> > > +
> > >  #include "memchr-evex-rtm.S"
> > > diff --git a/sysdeps/x86_64/multiarch/wmemchr-evex.S b/sysdeps/x86_64/multiarch/wmemchr-evex.S
> > > index 06cd0f9f5a..5512d5cdc3 100644
> > > --- a/sysdeps/x86_64/multiarch/wmemchr-evex.S
> > > +++ b/sysdeps/x86_64/multiarch/wmemchr-evex.S
> > > @@ -1,4 +1,7 @@
> > > -#define MEMCHR __wmemchr_evex
> > > -#define USE_AS_WMEMCHR 1
> > > +#ifndef WMEMCHR
> > > +# define WMEMCHR       __wmemchr_evex
> > > +#endif
> > > +#define USE_AS_WMEMCHR 1
> > > +#define MEMCHR WMEMCHR
> > >
> > >  #include "memchr-evex.S"
> > > diff --git a/sysdeps/x86_64/multiarch/wmemchr-sse2.S b/sysdeps/x86_64/multiarch/wmemchr-sse2.S
> > > index 70a965d552..b675a070d4 100644
> > > --- a/sysdeps/x86_64/multiarch/wmemchr-sse2.S
> > > +++ b/sysdeps/x86_64/multiarch/wmemchr-sse2.S
> > > @@ -1,4 +1,7 @@
> > > -#define USE_AS_WMEMCHR 1
> > > -#define wmemchr __wmemchr_sse2
> > > +#ifndef WMEMCHR
> > > +# define WMEMCHR       __wmemchr_sse2
> > > +#endif
> > > +#define USE_AS_WMEMCHR 1
> > > +#define MEMCHR WMEMCHR
> > >
> > > -#include "../memchr.S"
> > > +#include "memchr-sse2.S"
> > > diff --git a/sysdeps/x86_64/rawmemchr.S b/sysdeps/x86_64/rawmemchr.S
> > > index 4c1a3383b9..ba7e5202e6 100644
> > > --- a/sysdeps/x86_64/rawmemchr.S
> > > +++ b/sysdeps/x86_64/rawmemchr.S
> > > @@ -17,185 +17,13 @@
> > >     License along with the GNU C Library; if not, see
> > >     <https://www.gnu.org/licenses/>.  */
> > >
> > > -#include <sysdep.h>
> > > +#define RAWMEMCHR      __rawmemchr
> > >
> > > -       .text
> > > -ENTRY (__rawmemchr)
> > > -       movd    %rsi, %xmm1
> > > -       mov     %rdi, %rcx
> > > +#define DEFAULT_IMPL_V1        "multiarch/rawmemchr-sse2.S"
> > > +#define DEFAULT_IMPL_V3        "multiarch/rawmemchr-avx2.S"
> > > +#define DEFAULT_IMPL_V4        "multiarch/rawmemchr-evex.S"
> > >
> > > -       punpcklbw %xmm1, %xmm1
> > > -       punpcklbw %xmm1, %xmm1
> > > -
> > > -       and     $63, %rcx
> > > -       pshufd  $0, %xmm1, %xmm1
> > > -
> > > -       cmp     $48, %rcx
> > > -       ja      L(crosscache)
> > > -
> > > -       movdqu  (%rdi), %xmm0
> > > -       pcmpeqb %xmm1, %xmm0
> > > -/* Check if there is a match.  */
> > > -       pmovmskb %xmm0, %eax
> > > -       test    %eax, %eax
> > > -
> > > -       jnz     L(matches)
> > > -       add     $16, %rdi
> > > -       and     $-16, %rdi
> > > -       jmp     L(loop_prolog)
> > > -
> > > -       .p2align 4
> > > -L(crosscache):
> > > -       and     $15, %rcx
> > > -       and     $-16, %rdi
> > > -       movdqa  (%rdi), %xmm0
> > > -
> > > -       pcmpeqb %xmm1, %xmm0
> > > -/* Check if there is a match.  */
> > > -       pmovmskb %xmm0, %eax
> > > -/* Remove the leading bytes.  */
> > > -       sar     %cl, %eax
> > > -       test    %eax, %eax
> > > -       je      L(unaligned_no_match)
> > > -/* Check which byte is a match.  */
> > > -       bsf     %eax, %eax
> > > -
> > > -       add     %rdi, %rax
> > > -       add     %rcx, %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(unaligned_no_match):
> > > -       add     $16, %rdi
> > > -
> > > -       .p2align 4
> > > -L(loop_prolog):
> > > -       movdqa  (%rdi), %xmm0
> > > -       pcmpeqb %xmm1, %xmm0
> > > -       pmovmskb %xmm0, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches)
> > > -
> > > -       movdqa  16(%rdi), %xmm2
> > > -       pcmpeqb %xmm1, %xmm2
> > > -       pmovmskb %xmm2, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches16)
> > > -
> > > -       movdqa  32(%rdi), %xmm3
> > > -       pcmpeqb %xmm1, %xmm3
> > > -       pmovmskb %xmm3, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches32)
> > > -
> > > -       movdqa  48(%rdi), %xmm4
> > > -       pcmpeqb %xmm1, %xmm4
> > > -       add     $64, %rdi
> > > -       pmovmskb %xmm4, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches0)
> > > -
> > > -       test    $0x3f, %rdi
> > > -       jz      L(align64_loop)
> > > -
> > > -       movdqa  (%rdi), %xmm0
> > > -       pcmpeqb %xmm1, %xmm0
> > > -       pmovmskb %xmm0, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches)
> > > -
> > > -       movdqa  16(%rdi), %xmm2
> > > -       pcmpeqb %xmm1, %xmm2
> > > -       pmovmskb %xmm2, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches16)
> > > -
> > > -       movdqa  32(%rdi), %xmm3
> > > -       pcmpeqb %xmm1, %xmm3
> > > -       pmovmskb %xmm3, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches32)
> > > -
> > > -       movdqa  48(%rdi), %xmm3
> > > -       pcmpeqb %xmm1, %xmm3
> > > -       pmovmskb %xmm3, %eax
> > > -
> > > -       add     $64, %rdi
> > > -       test    %eax, %eax
> > > -       jnz     L(matches0)
> > > -
> > > -       and     $-64, %rdi
> > > -
> > > -       .p2align 4
> > > -L(align64_loop):
> > > -       movdqa  (%rdi), %xmm0
> > > -       movdqa  16(%rdi), %xmm2
> > > -       movdqa  32(%rdi), %xmm3
> > > -       movdqa  48(%rdi), %xmm4
> > > -
> > > -       pcmpeqb %xmm1, %xmm0
> > > -       pcmpeqb %xmm1, %xmm2
> > > -       pcmpeqb %xmm1, %xmm3
> > > -       pcmpeqb %xmm1, %xmm4
> > > -
> > > -       pmaxub  %xmm0, %xmm3
> > > -       pmaxub  %xmm2, %xmm4
> > > -       pmaxub  %xmm3, %xmm4
> > > -       pmovmskb %xmm4, %eax
> > > -
> > > -       add     $64, %rdi
> > > -
> > > -       test    %eax, %eax
> > > -       jz      L(align64_loop)
> > > -
> > > -       sub     $64, %rdi
> > > -
> > > -       pmovmskb %xmm0, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches)
> > > -
> > > -       pmovmskb %xmm2, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches16)
> > > -
> > > -       movdqa  32(%rdi), %xmm3
> > > -       pcmpeqb %xmm1, %xmm3
> > > -
> > > -       pcmpeqb 48(%rdi), %xmm1
> > > -       pmovmskb %xmm3, %eax
> > > -       test    %eax, %eax
> > > -       jnz     L(matches32)
> > > -
> > > -       pmovmskb %xmm1, %eax
> > > -       bsf     %eax, %eax
> > > -       lea     48(%rdi, %rax), %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(matches0):
> > > -       bsf     %eax, %eax
> > > -       lea     -16(%rax, %rdi), %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(matches):
> > > -       bsf     %eax, %eax
> > > -       add     %rdi, %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(matches16):
> > > -       bsf     %eax, %eax
> > > -       lea     16(%rax, %rdi), %rax
> > > -       ret
> > > -
> > > -       .p2align 4
> > > -L(matches32):
> > > -       bsf     %eax, %eax
> > > -       lea     32(%rax, %rdi), %rax
> > > -       ret
> > > -
> > > -END (__rawmemchr)
> > > +#include "isa-default-impl.h"
> > >
> > >  weak_alias (__rawmemchr, rawmemchr)
> > > -libc_hidden_builtin_def (__rawmemchr)
> > > +libc_hidden_def (__rawmemchr)
> > > diff --git a/sysdeps/x86_64/wmemchr.S b/sysdeps/x86_64/wmemchr.S
> > > new file mode 100644
> > > index 0000000000..eef91e556b
> > > --- /dev/null
> > > +++ b/sysdeps/x86_64/wmemchr.S
> > > @@ -0,0 +1,28 @@
> > > +/* Copyright (C) 2011-2022 Free Software Foundation, Inc.
> > > +   This file is part of the GNU C Library.
> > > +
> > > +   The GNU C Library is free software; you can redistribute it and/or
> > > +   modify it under the terms of the GNU Lesser General Public
> > > +   License as published by the Free Software Foundation; either
> > > +   version 2.1 of the License, or (at your option) any later version.
> > > +
> > > +   The GNU C Library is distributed in the hope that it will be useful,
> > > +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> > > +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> > > +   Lesser General Public License for more details.
> > > +
> > > +   You should have received a copy of the GNU Lesser General Public
> > > +   License along with the GNU C Library; if not, see
> > > +   <https://www.gnu.org/licenses/>.  */
> > > +
> > > +#define WMEMCHR        __wmemchr
> > > +
> > > +#define DEFAULT_IMPL_V1        "multiarch/wmemchr-sse2.S"
> > > +#define DEFAULT_IMPL_V3        "multiarch/wmemchr-avx2.S"
> > > +#define DEFAULT_IMPL_V4        "multiarch/wmemchr-evex.S"
> > > +
> > > +#include "isa-default-impl.h"
> > > +
> > > +libc_hidden_def (__wmemchr)
> > > +weak_alias (__wmemchr, wmemchr)
> > > +libc_hidden_weak (wmemchr)
> > > --
> > > 2.34.1
> > >
> >
> >
> > --
> > H.J.



-- 
H.J.

  reply	other threads:[~2022-06-22 22:14 UTC|newest]

Thread overview: 36+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-06-21 16:18 [PATCH v1] stdlib: Remove attr_write from mbstows if dst is NULL [BZ: 29265] Noah Goldstein
2022-06-22  7:09 ` Siddhesh Poyarekar
2022-06-22 15:24   ` Noah Goldstein
2022-06-22 15:24 ` [PATCH v2] " Noah Goldstein
2022-06-22 15:30   ` Siddhesh Poyarekar
2022-06-22 17:11 ` [PATCH v8 1/2] x86: Add defines / utilities for making ISA specific x86 builds Noah Goldstein
2022-06-22 17:12   ` [PATCH v8 2/2] x86: Add support for compiling {raw|w}memchr with high ISA level Noah Goldstein
2022-06-22 17:50     ` H.J. Lu
2022-06-22 18:10       ` Noah Goldstein
2022-06-22 17:14   ` [PATCH v8 1/2] x86: Add defines / utilities for making ISA specific x86 builds H.J. Lu
2022-06-22 18:11 ` [PATCH v9 " Noah Goldstein
2022-06-22 18:11   ` [PATCH v9 2/2] x86: Add support for compiling {raw|w}memchr with high ISA level Noah Goldstein
2022-06-22 18:38     ` H.J. Lu
2022-06-22 18:50       ` Noah Goldstein
2022-06-22 20:58 ` [PATCH v10 1/2] x86: Add defines / utilities for making ISA specific x86 builds Noah Goldstein
2022-06-22 20:58   ` [PATCH v10 2/2] x86: Add support for compiling {raw|w}memchr with high ISA level Noah Goldstein
2022-06-22 21:51     ` H.J. Lu
2022-06-22 22:04       ` Noah Goldstein
2022-06-22 22:14         ` H.J. Lu [this message]
2022-06-22 22:16       ` Noah Goldstein
2022-06-22 21:38   ` [PATCH v10 1/2] x86: Add defines / utilities for making ISA specific x86 builds H.J. Lu
2022-06-22 21:51     ` Noah Goldstein
2022-06-22 21:48 ` [PATCH v11 " Noah Goldstein
2022-06-22 21:48   ` [PATCH v11 2/2] x86: Add support for compiling {raw|w}memchr with high ISA level Noah Goldstein
2022-06-22 21:54   ` [PATCH v11 1/2] x86: Add defines / utilities for making ISA specific x86 builds H.J. Lu
2022-06-22 22:16 ` [PATCH v12 " Noah Goldstein
2022-06-22 22:16   ` [PATCH v12 2/2] x86: Add support for compiling {raw|w}memchr with high ISA level Noah Goldstein
2022-06-22 22:54 ` [PATCH v13 1/2] x86: Add defines / utilities for making ISA specific x86 builds Noah Goldstein
2022-06-22 22:54   ` [PATCH v13 2/2] x86: Add support for compiling {raw|w}memchr with high ISA level Noah Goldstein
2022-06-22 23:51 ` [PATCH v14 1/2] x86: Add defines / utilities for making ISA specific x86 builds Noah Goldstein
2022-06-22 23:51   ` [PATCH v14 2/2] x86: Add support for compiling {raw|w}memchr with high ISA level Noah Goldstein
2022-06-23  2:05     ` H.J. Lu
2022-06-23 17:14     ` Joseph Myers
2022-06-23 17:32       ` Noah Goldstein
2022-06-23 18:14         ` Noah Goldstein
2022-06-23  2:06   ` [PATCH v14 1/2] x86: Add defines / utilities for making ISA specific x86 builds H.J. Lu

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