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| author | Noah Goldstein <goldstein.w.n@gmail.com> | 2022-07-13 16:32:59 -0700 |
|---|---|---|
| committer | Noah Goldstein <goldstein.w.n@gmail.com> | 2022-07-16 03:07:59 -0700 |
| commit | ceabdcd130ca7043b0fcf2676183d79431d10493 (patch) | |
| tree | f6ced435023b66ac1f3b519e5b26a60ef8f479dd /sysdeps/x86_64/strchr-isa-default-impl.h | |
| parent | c353689e49e72f3aafa1a9e68d4f7a4f33a79cbe (diff) | |
| download | glibc-ceabdcd130ca7043b0fcf2676183d79431d10493.tar.gz | |
x86: Add support to build strcmp/strlen/strchr with explicit ISA level
1. Add default ISA level selection in non-multiarch/rtld
implementations.
2. Add ISA level build guards to different implementations.
- I.e strcmp-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 (strcmp-evex.S).
3. 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.
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.
Diffstat (limited to 'sysdeps/x86_64/strchr-isa-default-impl.h')
| -rw-r--r-- | sysdeps/x86_64/strchr-isa-default-impl.h | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/sysdeps/x86_64/strchr-isa-default-impl.h b/sysdeps/x86_64/strchr-isa-default-impl.h new file mode 100644 index 0000000000..0c8cbc6ffb --- /dev/null +++ b/sysdeps/x86_64/strchr-isa-default-impl.h @@ -0,0 +1,28 @@ +/* Set default strchr impl based on ISA level. + 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 <isa-level.h> +#if MINIMUM_X86_ISA_LEVEL == 1 || MINIMUM_X86_ISA_LEVEL == 2 +# define DEFAULT_STRCHR __strchr_sse2 +#elif MINIMUM_X86_ISA_LEVEL == 3 +# define DEFAULT_STRCHR __strchr_avx2 +#elif MINIMUM_X86_ISA_LEVEL == 4 +# define DEFAULT_STRCHR __strchr_evex +#else +# error "Unknown default strchr implementation" +#endif |