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d3496c9f4f
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. |
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| aarch64 | ||
| alpha | ||
| arm | ||
| generic | ||
| gnu | ||
| hppa | ||
| i386 | ||
| ia64 | ||
| ieee754 | ||
| init_array | ||
| m68k | ||
| mach | ||
| microblaze | ||
| mips | ||
| nacl | ||
| nios2 | ||
| nptl | ||
| posix | ||
| powerpc | ||
| pthread | ||
| s390 | ||
| sh | ||
| sparc | ||
| tile | ||
| unix | ||
| wordsize-32 | ||
| wordsize-64 | ||
| x86 | ||
| x86_64 | ||