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/*
* Written by J.T. Conklin <jtc@netbsd.org>.
* Public domain.
* Adapted for NetBSD/x86_64 by Frank van der Linden <fvdl@wasabisystems.com>
*/
#include <machine/asm.h>
#if defined(LIBC_SCCS)
RCSID("$NetBSD: memchr.S,v 1.1 2001/06/19 00:22:46 fvdl Exp $")
#endif
ENTRY(memchr)
movb %sil,%al /* set character to search for */
movq %rdx,%rcx /* set length of search */
testq %rcx,%rcx /* test for len == 0 */
jz L1
cld /* set search forward */
repne /* search! */
scasb
jne L1 /* scan failed, return null */
leaq -1(%rdi),%rax /* adjust result of scan */
ret
L1: xorq %rax,%rax
ret
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