[PATCH] x86-64: Add wcslen optimize for sse4.1
Noah Goldstein
goldstein.w.n@gmail.com
Wed Jun 23 06:34:28 GMT 2021
On Wed, Jun 23, 2021 at 2:29 AM Noah Goldstein <goldstein.w.n@gmail.com>
wrote:
> No bug. This comment adds the ifunc / build infrastructure
> necessary for wcslen to prefer the sse4.1 implementation
> in strlen-vec.S. test-wcslen.c is passing.
>
> Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com>
> ---
> Rebased on [PATCH] x86-64: Move strlen.S to multiarch/strlen-vec.S
> sysdeps/x86_64/multiarch/Makefile | 4 +-
> sysdeps/x86_64/multiarch/ifunc-impl-list.c | 3 ++
> sysdeps/x86_64/multiarch/ifunc-wcslen.h | 52 ++++++++++++++++++++++
> sysdeps/x86_64/multiarch/wcslen-sse4_1.S | 4 ++
> sysdeps/x86_64/multiarch/wcslen.c | 2 +-
> sysdeps/x86_64/multiarch/wcsnlen.c | 34 +-------------
> 6 files changed, 63 insertions(+), 36 deletions(-)
> create mode 100644 sysdeps/x86_64/multiarch/ifunc-wcslen.h
> create mode 100644 sysdeps/x86_64/multiarch/wcslen-sse4_1.S
>
> diff --git a/sysdeps/x86_64/multiarch/Makefile
> b/sysdeps/x86_64/multiarch/Makefile
> index 2c2aad3a7e..26be40959c 100644
> --- a/sysdeps/x86_64/multiarch/Makefile
> +++ b/sysdeps/x86_64/multiarch/Makefile
> @@ -95,8 +95,8 @@ sysdep_routines += wmemcmp-sse4 wmemcmp-ssse3 wmemcmp-c \
> wcscpy-ssse3 wcscpy-c \
> wcschr-sse2 wcschr-avx2 \
> wcsrchr-sse2 wcsrchr-avx2 \
> - wcsnlen-sse4_1 wcsnlen-c \
> - wcslen-sse2 wcslen-avx2 wcsnlen-avx2 \
> + wcslen-sse2 wcslen-sse4_1 wcslen-avx2 \
> + wcsnlen-c wcsnlen-sse4_1 wcsnlen-avx2 \
> wcschr-avx2-rtm \
> wcscmp-avx2-rtm \
> wcslen-avx2-rtm \
> diff --git a/sysdeps/x86_64/multiarch/ifunc-impl-list.c
> b/sysdeps/x86_64/multiarch/ifunc-impl-list.c
> index 15eda47667..dbd1ebf298 100644
> --- a/sysdeps/x86_64/multiarch/ifunc-impl-list.c
> +++ b/sysdeps/x86_64/multiarch/ifunc-impl-list.c
> @@ -684,6 +684,9 @@ __libc_ifunc_impl_list (const char *name, struct
> libc_ifunc_impl *array,
> && CPU_FEATURE_USABLE (AVX512BW)
> && CPU_FEATURE_USABLE (BMI2)),
> __wcslen_evex)
> + IFUNC_IMPL_ADD (array, i, wcsnlen,
> + CPU_FEATURE_USABLE (SSE4_1),
> + __wcsnlen_sse4_1)
> IFUNC_IMPL_ADD (array, i, wcslen, 1, __wcslen_sse2))
>
> /* Support sysdeps/x86_64/multiarch/wcsnlen.c. */
> diff --git a/sysdeps/x86_64/multiarch/ifunc-wcslen.h
> b/sysdeps/x86_64/multiarch/ifunc-wcslen.h
> new file mode 100644
> index 0000000000..39e3347378
> --- /dev/null
> +++ b/sysdeps/x86_64/multiarch/ifunc-wcslen.h
> @@ -0,0 +1,52 @@
> +/* Common definition for ifunc selections for wcslen and wcsnlen
> + All versions must be listed in ifunc-impl-list.c.
> + Copyright (C) 2017-2021 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 <init-arch.h>
> +
> +extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
> +extern __typeof (REDIRECT_NAME) OPTIMIZE (sse4_1) 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;
> +
> +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))
> + {
> + if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
> + && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
> + return OPTIMIZE (evex);
> +
> + if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
> + return OPTIMIZE (avx2_rtm);
> +
> + if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
> + return OPTIMIZE (avx2);
> + }
> +
> + if (CPU_FEATURE_USABLE_P (cpu_features, SSE4_1))
> + return OPTIMIZE (sse4_1);
> +
> + return OPTIMIZE (sse2);
> +}
> diff --git a/sysdeps/x86_64/multiarch/wcslen-sse4_1.S
> b/sysdeps/x86_64/multiarch/wcslen-sse4_1.S
> new file mode 100644
> index 0000000000..7e62621afc
> --- /dev/null
> +++ b/sysdeps/x86_64/multiarch/wcslen-sse4_1.S
> @@ -0,0 +1,4 @@
> +#define AS_WCSLEN
> +#define strlen __wcslen_sse4_1
> +
> +#include "strlen-vec.S"
> diff --git a/sysdeps/x86_64/multiarch/wcslen.c
> b/sysdeps/x86_64/multiarch/wcslen.c
> index f89bed42a0..3032061d3b 100644
> --- a/sysdeps/x86_64/multiarch/wcslen.c
> +++ b/sysdeps/x86_64/multiarch/wcslen.c
> @@ -24,7 +24,7 @@
> # undef __wcslen
>
> # define SYMBOL_NAME wcslen
> -# include "ifunc-avx2.h"
> +# include "ifunc-wcslen.h"
>
> libc_ifunc_redirected (__redirect_wcslen, __wcslen, IFUNC_SELECTOR ());
> weak_alias (__wcslen, wcslen);
> diff --git a/sysdeps/x86_64/multiarch/wcsnlen.c
> b/sysdeps/x86_64/multiarch/wcsnlen.c
> index 4983f1b222..2963fbe059 100644
> --- a/sysdeps/x86_64/multiarch/wcsnlen.c
> +++ b/sysdeps/x86_64/multiarch/wcsnlen.c
> @@ -24,39 +24,7 @@
> # undef __wcsnlen
>
> # define SYMBOL_NAME wcsnlen
> -# include <init-arch.h>
> -
> -extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
> -extern __typeof (REDIRECT_NAME) OPTIMIZE (sse4_1) 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;
> -
> -static inline void *
> -IFUNC_SELECTOR (void)
> -{
> - const struct cpu_features* cpu_features = __get_cpu_features ();
> -
> - if (CPU_FEATURE_USABLE_P (cpu_features, AVX2)
> - && 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)
> - && CPU_FEATURE_USABLE_P (cpu_features, BMI2))
> - return OPTIMIZE (evex);
> -
> - if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
> - return OPTIMIZE (avx2_rtm);
> -
> - if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
> - return OPTIMIZE (avx2);
> - }
> -
> - if (CPU_FEATURE_USABLE_P (cpu_features, SSE4_1))
> - return OPTIMIZE (sse4_1);
> -
> - return OPTIMIZE (sse2);
> -}
> +# include "ifunc-wcslen.h"
>
> libc_ifunc_redirected (__redirect_wcsnlen, __wcsnlen, IFUNC_SELECTOR ());
> weak_alias (__wcsnlen, wcsnlen);
> --
> 2.25.1
>
>
More information about the Libc-alpha
mailing list