1/* $OpenBSD: strlen.S,v 1.3 2005/08/07 11:30:38 espie Exp $ */ 2/* 3 * Written by J.T. Conklin <jtc@netbsd.org>. 4 * Public domain. 5 */ 6 7#include <machine/asm.h> 8 9ENTRY(strlen) 10 pushl %edi 11 movl 8(%esp),%edi /* string address */ 12 cld /* set search forward */ 13 xorl %eax,%eax /* set search for null terminator */ 14 movl $-1,%ecx /* set search for lots of characters */ 15 repne /* search! */ 16 scasb 17 notl %ecx /* get length by taking complement */ 18 leal -1(%ecx),%eax /* and subtracting one */ 19 popl %edi 20 ret 21