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* x86: Add support for building {w}memset{_chk} with explicit ISA levelNoah Goldstein2022-07-051-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1. Refactor files so that all implementations are in the multiarch directory - Moved the implementation portion of memset sse2 from memset.S to multiarch/memset-sse2.S - The non-multiarch 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 memset-avx2-unaligned-erms.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 (memset-evex-unaligned-erms.S). 3. Add new multiarch/rtld-memset.S that just include the non-multiarch memset.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. 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.
* Remove x86-64 rtld-xxx.c and rtld-xxx.SH.J. Lu2015-08-251-1/+0
| | | | | | | | | | | | Since ld.so preserves vector registers now, we can use the regular, non-ifunc string and memory functions in ld.so. * sysdeps/x86_64/rtld-memcmp.c: Removed. * sysdeps/x86_64/rtld-memset.S: Likewise. * sysdeps/x86_64/rtld-strchr.S: Likewise. * sysdeps/x86_64/rtld-strlen.S: Likewise. * sysdeps/x86_64/multiarch/rtld-memcmp.c: Likewise. * sysdeps/x86_64/multiarch/rtld-memset.S: Likewise.
* Add x86_64 memset optimized for AVX2Ling Ma2014-06-191-0/+1
In this patch we take advantage of HSW memory bandwidth, manage to reduce miss branch prediction by avoiding using branch instructions and force destination to be aligned with avx & avx2 instruction. The CPU2006 403.gcc benchmark indicates this patch improves performance from 26% to 59%. * sysdeps/x86_64/multiarch/Makefile: Add memset-avx2. * sysdeps/x86_64/multiarch/memset-avx2.S: New file. * sysdeps/x86_64/multiarch/memset.S: Likewise. * sysdeps/x86_64/multiarch/memset_chk.S: Likewise. * sysdeps/x86_64/multiarch/rtld-memset.S: Likewise.