glibc/sysdeps/x86_64/multiarch/wmemchr-sse2.S

#ifndef WMEMCHR
# define WMEMCHR	__wmemchr_sse2
#endif
#define USE_AS_WMEMCHR	1
#define MEMCHR	WMEMCHR

#include "memchr-sse2.S"
x86: Add support for compiling {raw\|w}memchr with high ISA level 1. Refactor files so that all implementations for in the multiarch directory. - Essentially moved sse2 {raw\|w}memchr.S implementation to multiarch/{raw\|w}memchr-sse2.S - The non-multiarch {raw\|w}memchr.S 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 memchr-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 (memchr-evex{-rtm}.S). 3. Add new multiarch/rtld-{raw}memchr.S that just include the non-multiarch {raw}memchr.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. - Guranteed replacement essentially means that for any ISA level build there must be a function that the baseline of the ISA supports. So for {raw\|w}memchr.S since there is not ISA level 2 function, the ISA level 2 build still includes the ISA level 1 (sse2) function. Once we reach the ISA level 3 build, however, {raw\|w}memchr-avx2{-rtm}.S will always be sufficient so the ISA level 1 implementation ({raw\|w}memchr-sse2.S) will not be built. 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. 2022-06-22 23:51:20 +00:00			`#ifndef WMEMCHR`
			`# define WMEMCHR __wmemchr_sse2`
			`#endif`
			`#define USE_AS_WMEMCHR 1`
			`#define MEMCHR WMEMCHR`
x86-64: Optimize memchr/rawmemchr/wmemchr with SSE2/AVX2 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. 2017-06-09 12:13:15 +00:00
x86: Add support for compiling {raw\|w}memchr with high ISA level 1. Refactor files so that all implementations for in the multiarch directory. - Essentially moved sse2 {raw\|w}memchr.S implementation to multiarch/{raw\|w}memchr-sse2.S - The non-multiarch {raw\|w}memchr.S 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 memchr-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 (memchr-evex{-rtm}.S). 3. Add new multiarch/rtld-{raw}memchr.S that just include the non-multiarch {raw}memchr.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. - Guranteed replacement essentially means that for any ISA level build there must be a function that the baseline of the ISA supports. So for {raw\|w}memchr.S since there is not ISA level 2 function, the ISA level 2 build still includes the ISA level 1 (sse2) function. Once we reach the ISA level 3 build, however, {raw\|w}memchr-avx2{-rtm}.S will always be sufficient so the ISA level 1 implementation ({raw\|w}memchr-sse2.S) will not be built. 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. 2022-06-22 23:51:20 +00:00			`#include "memchr-sse2.S"`