1/* $NetBSD: bcmp.S,v 1.4 2011/01/25 02:38:15 matt Exp $ */ 2/* 3 * Copyright (c) 1983, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. Neither the name of the University nor the names of its contributors 15 * may be used to endorse or promote products derived from this software 16 * without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31/* bcmp(s1, s2, n) */ 32 33#include "DEFS.h" 34 35#ifdef LIBC_SCCS 36RCSID("$NetBSD: bcmp.S,v 1.4 2011/01/25 02:38:15 matt Exp $") 37#endif 38 39/* Since "cmpc3" is not portable across VAXen, do it the hard way */ 40/* still, this is four times faster than the generic C version on a uvax2 */ 41 42ENTRY(bcmp, 0) 43 movl 12(%ap),%r0 # %r0 = n 44 jeql 9f 45 movq 4(%ap),%r1 # %r1 = s1, %r2 = s2 46 ashl $-2,%r0,%r3 # convert len to # of long words 47 jeql 2f 481: 49 cmpl (%r1)+,(%r2)+ # no "cmpq" alas, so four bytes at a time 50 jneq 9f 51 sobgtr %r3,1b 522: 53 bicl3 $-4,%r0,%r3 # handle at most 3 extra bytes 54 jeql 8f 553: 56 cmpb (%r1)+,(%r2)+ 57 jneq 9f 58 sobgtr %r3,3b 598: 60 clrl %r0 # we have a match! 619: 62 ret 63END(bcmp) 64