glibc/strchrnul-avx2.S at fd860eaaa8757b221d9169e460c9ec41ea51f317 - glibc - Gitea: Git with a cup of tea

AuroraMiddleware/glibc

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H.J. Lu 8fe57365bf x86-64: Optimize strchr/strchrnul/wcschr with AVX2

Optimize strchr/strchrnul/wcschr with AVX2 to search 32 bytes with vector
instructions.  It is as fast as SSE2 versions for size <= 16 bytes and up
to 1X faster for or size > 16 bytes on Haswell.  Select AVX2 version 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/multiarch/Makefile (sysdep_routines): Add
	strchr-sse2, strchrnul-sse2, strchr-avx2, strchrnul-avx2,
	wcschr-sse2 and wcschr-avx2.
	* sysdeps/x86_64/multiarch/ifunc-impl-list.c
	(__libc_ifunc_impl_list): Add tests for __strchr_avx2,
	__strchrnul_avx2, __strchrnul_sse2, __wcschr_avx2 and
	__wcschr_sse2.
	* sysdeps/x86_64/multiarch/strchr-avx2.S: New file.
	* sysdeps/x86_64/multiarch/strchr-sse2.S: Likewise.
	* sysdeps/x86_64/multiarch/strchr.c: Likewise.
	* sysdeps/x86_64/multiarch/strchrnul-avx2.S: Likewise.
	* sysdeps/x86_64/multiarch/strchrnul-sse2.S: Likewise.
	* sysdeps/x86_64/multiarch/strchrnul.c: Likewise.
	* sysdeps/x86_64/multiarch/wcschr-avx2.S: Likewise.
	* sysdeps/x86_64/multiarch/wcschr-sse2.S: Likewise.
	* sysdeps/x86_64/multiarch/wcschr.c: Likewise.
	* sysdeps/x86_64/multiarch/strchr.S: Removed.

2017-06-09 05:42:29 -07:00

4 lines

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ArmAsm

Raw Blame History

	`#define STRCHR __strchrnul_avx2`
	`#define USE_AS_STRCHRNUL 1`
	`#include "strchr-avx2.S"`