xref: /freebsd/lib/libc/i386/string/wcslen.S (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1/*-
2 * Copyright (c) 2003 Tim J. Robbins.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <machine/asm.h>
28/*
29 * size_t
30 * wcslen(const wchar_t *s) --
31 *	Find the length of a wide character string.
32 */
33ENTRY(wcslen)
34	movl	4(%esp),%ecx		/* String */
35	pushl	%ebx
36	xorl	%ebx,%ebx
37	xorl	%eax,%eax
38.p2align 4,0x90
39L1:	cmpl	%ebx,(%ecx)
40	jz	found0
41	cmpl	%ebx,4(%ecx)
42	jz	found1
43	cmpl	%ebx,8(%ecx)
44	jz	found2
45	cmpl	%ebx,12(%ecx)
46	jz	found3
47	cmpl	%ebx,16(%ecx)
48	jz	found4
49	cmpl	%ebx,20(%ecx)
50	jz	found5
51	cmpl	%ebx,24(%ecx)
52	jz	found6
53	cmpl	%ebx,28(%ecx)
54	jz	found7
55	leal	32(%ecx),%ecx
56	addl	$8,%eax
57	jmp	L1
58found7:	incl	%eax
59found6:	incl	%eax
60found5:	incl	%eax
61found4:	incl	%eax
62found3:	incl	%eax
63found2:	incl	%eax
64found1:	incl	%eax
65found0:	popl	%ebx
66	ret
67END(wcslen)
68
69	.section .note.GNU-stack,"",%progbits
70