diff options
| author | Wilco Dijkstra <wdijkstr@arm.com> | 2016-03-25 16:44:26 -0300 |
|---|---|---|
| committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2016-04-01 10:44:40 -0300 |
| commit | d3496c9f4f27d3009b71be87f6108b4fed7314bd (patch) | |
| tree | eefcd05beb1f6ed269167433a763c234483b7c0b /sysdeps | |
| parent | d8a012c5c9e4bfc1b8db2bc6deacb85b44a2e1eb (diff) | |
| download | glibc-d3496c9f4f27d3009b71be87f6108b4fed7314bd.tar.gz | |
Improve generic strcspn performance
Improve strcspn performance using a much faster algorithm. It is kept simple
so it works well on most targets. It is generally at least 10 times faster
than the existing implementation on bench-strcspn on a few AArch64
implementations, and for some tests 100 times as fast (repeatedly calling
strchr on a small string is extremely slow...).
In fact the string/bits/string2.h inlines make no longer sense, as GCC
already uses strlen if reject is an empty string, strchrnul is 5 times as
fast as __strcspn_c1, while __strcspn_c2 and __strcspn_c3 are slower than
the strcspn main loop for large strings (though reject length 2-4 could be
special cased in the future to gain even more performance).
Tested on x86_64, i686, and aarch64.
* string/Version (libc): Add GLIBC_2.24.
* string/strcspn.c (strcspn): Rewrite function.
* string/bits/string2.h (strcspn): Use __builtin_strcspn.
(__strcspn_c1): Remove inline function.
(__strcspn_c2): Likewise.
(__strcspn_c3): Likewise.
* string/string-inline.c
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strcspn_c1): Add
compatibility symbol.
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strcspn_c2):
Likewise.
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strcspn_c3):
Likewise.
* sysdeps/i386/string-inlines.c: Include generic string-inlines.c.
Diffstat (limited to 'sysdeps')
| -rw-r--r-- | sysdeps/i386/string-inlines.c | 19 |
1 files changed, 1 insertions, 18 deletions
diff --git a/sysdeps/i386/string-inlines.c b/sysdeps/i386/string-inlines.c index c7de270c0a..64d80e8eef 100644 --- a/sysdeps/i386/string-inlines.c +++ b/sysdeps/i386/string-inlines.c @@ -15,27 +15,10 @@ License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ -/* <bits/string.h> and <bits/string2.h> declare some extern inline - functions. These functions are declared additionally here if - inlining is not possible. */ - -#undef __USE_STRING_INLINES -#define __USE_STRING_INLINES -#define _FORCE_INLINES -#define __STRING_INLINE /* empty */ -#define __NO_INLINE__ - /* This is to avoid PLT entries for the x86 version. */ #define __memcpy_g __memcpy_g_internal #define __strchr_g __strchr_g_internal - -#include <string.h> -#undef index -#undef rindex - -#undef __NO_INLINE__ -#include <bits/string.h> -#include <bits/string2.h> +#include <string/string-inlines.c> void * (__memcpy_c) (void *d, const void *s, size_t n) |