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| author | Noah Goldstein <goldstein.w.n@gmail.com> | 2022-06-29 16:11:22 -0700 |
|---|---|---|
| committer | Noah Goldstein <goldstein.w.n@gmail.com> | 2022-07-05 16:42:42 -0700 |
| commit | ae308947ff0fa950431d53bcc90c875295d57715 (patch) | |
| tree | d14ede08a3dae637cdd57410d42e3dcf00624e2c /sysdeps/x86_64/wmemcmp.S | |
| parent | 37ecc657b22c3367a56df5ebd53908e34e65fa16 (diff) | |
| download | glibc-ae308947ff0fa950431d53bcc90c875295d57715.tar.gz glibc-ae308947ff0fa950431d53bcc90c875295d57715.tar.xz glibc-ae308947ff0fa950431d53bcc90c875295d57715.zip | |
x86: Add support for building {w}memcmp{eq} with explicit ISA level
1. Refactor files so that all implementations are in the multiarch
directory
- Moved the implementation portion of memcmp sse2 from memcmp.S to
multiarch/memcmp-sse2.S
- The non-multiarch 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 memcmp-avx2-movsb.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 (memcmp-evex-movbe.S).
3. Add new multiarch/rtld-{w}memcmp{eq}.S that just include the
non-multiarch {w}memcmp{eq}.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.
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/wmemcmp.S')
| -rw-r--r-- | sysdeps/x86_64/wmemcmp.S | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/sysdeps/x86_64/wmemcmp.S b/sysdeps/x86_64/wmemcmp.S index 815b999e4e..cf90a64c95 100644 --- a/sysdeps/x86_64/wmemcmp.S +++ b/sysdeps/x86_64/wmemcmp.S @@ -1,4 +1,4 @@ -/* wmemcmp optimized with SSE2. +/* wmemcmp hook for non-multiarch and RTLD build. Copyright (C) 2022 Free Software Foundation, Inc. This file is part of the GNU C Library. @@ -16,8 +16,12 @@ License along with the GNU C Library; if not, see <https://www.gnu.org/licenses/>. */ -#define MEMCMP __wmemcmp -#define USE_AS_WMEMCMP 1 -#include "memcmp.S" +#define WMEMCMP __wmemcmp + +#define DEFAULT_IMPL_V1 "multiarch/wmemcmp-sse2.S" +#define DEFAULT_IMPL_V3 "multiarch/wmemcmp-avx2-movbe.S" +#define DEFAULT_IMPL_V4 "multiarch/wmemcmp-evex-movbe.S" + +#include "isa-default-impl.h" weak_alias (__wmemcmp, wmemcmp) |