mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-26 04:31:03 +00:00
2f5d20ac99
SSE2 memchr is extended to support wmemchr. AVX2 memchr/rawmemchr/wmemchr are added to search 32 bytes with a single vector compare instruction. AVX2 memchr/rawmemchr/wmemchr are as fast as SSE2 memchr/rawmemchr/wmemchr for small sizes and up to 1.5X faster for larger sizes on Haswell and Skylake. Select AVX2 memchr/rawmemchr/wmemchr on AVX2 machines where vzeroupper is preferred and AVX unaligned load is fast. NB: It uses TZCNT instead of BSF since TZCNT produces the same result as BSF for non-zero input. TZCNT is faster than BSF and is executed as BSF if machine doesn't support TZCNT. * sysdeps/x86_64/memchr.S (MEMCHR): New. Depending on if USE_AS_WMEMCHR is defined. (PCMPEQ): Likewise. (memchr): Renamed to ... (MEMCHR): This. Support wmemchr if USE_AS_WMEMCHR is defined. Replace pcmpeqb with PCMPEQ. * sysdeps/x86_64/multiarch/Makefile (sysdep_routines): Add memchr-sse2, rawmemchr-sse2, memchr-avx2, rawmemchr-avx2, wmemchr-sse4_1, wmemchr-avx2 and wmemchr-c. * sysdeps/x86_64/multiarch/ifunc-avx2.h: New file. * sysdeps/x86_64/multiarch/memchr-avx2.S: Likewise. * sysdeps/x86_64/multiarch/memchr-sse2.S: Likewise. * sysdeps/x86_64/multiarch/memchr.c: Likewise. * sysdeps/x86_64/multiarch/rawmemchr-avx2.S: Likewise. * sysdeps/x86_64/multiarch/rawmemchr-sse2.S: Likewise. * sysdeps/x86_64/multiarch/rawmemchr.c: Likewise. * sysdeps/x86_64/multiarch/wmemchr-avx2.S: Likewise. * sysdeps/x86_64/multiarch/wmemchr-sse2.S: Likewise. * sysdeps/x86_64/multiarch/wmemchr.c: Likewise. * sysdeps/x86_64/multiarch/ifunc-impl-list.c (__libc_ifunc_impl_list): Test __memchr_avx2, __memchr_sse2, __rawmemchr_avx2, __rawmemchr_sse2, __wmemchr_avx2 and __wmemchr_sse2.
30 lines
1.1 KiB
ArmAsm
30 lines
1.1 KiB
ArmAsm
/* rawmemchr optimized with SSE2.
|
|
Copyright (C) 2017 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
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
/* Define multiple versions only for the definition in libc. */
|
|
#if IS_IN (libc)
|
|
# define __rawmemchr __rawmemchr_sse2
|
|
|
|
# undefine weak_alias
|
|
# define weak_alias(__rawmemchr, rawmemchr)
|
|
# undef libc_hidden_def
|
|
# define libc_hidden_def(__rawmemchr)
|
|
#endif
|
|
|
|
#include "../rawmemchr.S"
|