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