/* $NetBSD: strncmp.S,v 1.2 2013/08/19 00:57:25 matt Exp $ */ /* * Copyright (c) 2002 ARM Ltd * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the company may not be used to endorse or promote * products derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include <machine/asm.h> RCSID("$NetBSD: strncmp.S,v 1.2 2013/08/19 00:57:25 matt Exp $") ENTRY(strncmp) /* if ((len - 1) < 0) return 0 */ subs r2, r2, #1 #ifdef __thumb__ bmi 5f #else movmi r0, #0 RETc(mi) #endif /* ip == last src address to compare */ #ifdef __thumb__ adds r3, r0, r2 mov ip, r3 subs r1, r1, r0 #else add ip, r0, r2 #endif 1: #ifdef __thumb__ ldrb r2, [r0] ldrb r3, [r1, r0] adds r0, r0, #1 cmp ip, r0 /* exhausted length? */ bcc 4f /* yes, we're done */ cmp r2, #1 /* NUL? */ bcc 4f /* yes, we're done */ cmp r2, r3 /* different? */ #else ldrb r2, [r0], #1 ldrb r3, [r1], #1 cmp ip, r0 cmpcs r2, #1 cmpcs r2, r3 #endif beq 1b 4: subs r0, r2, r3 RET #ifdef __thumb__ 5: movs r0, #0 RET #endif END(strncmp) |