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/* $OpenBSD: memchr.S,v 1.2 2014/11/29 18:51:23 tedu Exp $ */
/*
* Written by J.T. Conklin <jtc@netbsd.org>.
* Public domain.
*/
#include <machine/asm.h>
ENTRY(memchr)
pushl %edi
movl 8(%esp),%edi /* string address */
movl 12(%esp),%eax /* set character to search for */
movl 16(%esp),%ecx /* set length of search */
testl %ecx,%ecx /* test for len == 0 */
jz L1
repne /* search! */
scasb
jne L1 /* scan failed, return null */
leal -1(%edi),%eax /* adjust result of scan */
popl %edi
ret
.align 2,0x90
L1: xorl %eax,%eax
popl %edi
ret
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