1/* $NetBSD: strlen.S,v 1.2 2009/12/14 00:39:00 matt Exp $ */ 2 3/*- 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Ralph Campbell. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35#include <machine/asm.h> 36__FBSDID("$FreeBSD$"); 37 38#if defined(LIBC_SCCS) && !defined(lint) 39 ASMSTR("from: @(#)strlen.s 8.1 (Berkeley) 6/4/93") 40 ASMSTR("$NetBSD: strlen.S,v 1.2 2009/12/14 00:39:00 matt Exp $") 41#endif /* LIBC_SCCS and not lint */ 42 43#ifdef __ABICALLS__ 44 .abicalls 45#endif 46 47LEAF(strlen) 48 PTR_ADDU v1, a0, 1 491: 50 lb v0, 0(a0) # get byte from string 51 PTR_ADDU a0, a0, 1 # increment pointer 52 bne v0, zero, 1b # continue if not end 53 PTR_SUBU v0, a0, v1 # compute length - 1 for '\0' char 54 j ra 55END(strlen) 56