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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/multiarch/strlen-sse2.S | |
| parent | c353689e49e72f3aafa1a9e68d4f7a4f33a79cbe (diff) | |
| download | glibc-ceabdcd130ca7043b0fcf2676183d79431d10493.tar.gz glibc-ceabdcd130ca7043b0fcf2676183d79431d10493.tar.xz glibc-ceabdcd130ca7043b0fcf2676183d79431d10493.zip | |
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/multiarch/strlen-sse2.S')
| -rw-r--r-- | sysdeps/x86_64/multiarch/strlen-sse2.S | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/sysdeps/x86_64/multiarch/strlen-sse2.S b/sysdeps/x86_64/multiarch/strlen-sse2.S index 5be72267d5..a96ccbb2d5 100644 --- a/sysdeps/x86_64/multiarch/strlen-sse2.S +++ b/sysdeps/x86_64/multiarch/strlen-sse2.S @@ -16,15 +16,20 @@ License along with the GNU C Library; if not, see <https://www.gnu.org/licenses/>. */ -#if IS_IN (libc) || defined STRLEN - -# ifndef STRLEN -# define STRLEN __strlen_sse2 -# endif +#include <isa-level.h> +/* ISA level >= 2 for both strlen and wcslen. wcslen uses `pminud` + which is SSE4.1. strlen doesn't have an ISA level == 2 + implementation so the SSE2 implementation must be built with ISA + level == 2. */ +# if ISA_SHOULD_BUILD (2) # include <sysdep.h> +# ifndef STRLEN +# define STRLEN __strlen_sse2 +# endif + # ifdef AS_WCSLEN # define PMINU pminud # define PCMPEQ pcmpeqd @@ -82,7 +87,7 @@ L(n_nonzero): suffice. */ mov %RSI_LP, %R10_LP sar $62, %R10_LP - jnz __wcslen_sse4_1 + jnz OVERFLOW_STRLEN sal $2, %RSI_LP # endif |