minix/lib/libc/arch/vax/string/bcopy.S

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/* $NetBSD: bcopy.S,v 1.4 2011/01/25 02:38:15 matt Exp $ */
/*
* Copyright (c) 1983, 1993
* The Regents of the University of California. 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. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 THE REGENTS OR CONTRIBUTORS 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.
*/
/* bcopy(from, to, size) */
#include "DEFS.h"
#if defined(LIBC_SCCS)
/* .asciz "@(#)bcopy.s 8.1 (Berkeley) 6/4/93" */
RCSID("$NetBSD: bcopy.S,v 1.4 2011/01/25 02:38:15 matt Exp $")
#endif
ENTRY(bcopy, R6)
movl 4(%ap),%r1
movl 8(%ap),%r3
movl 12(%ap),%r6
cmpl %r1,%r3
bgtr 2f # normal forward case
blss 3f # overlapping, must do backwards
ret # equal, nothing to do
1:
subl2 %r0,%r6
movc3 %r0,(%r1),(%r3)
2:
movzwl $65535,%r0
cmpl %r6,%r0
jgtr 1b
movc3 %r6,(%r1),(%r3)
ret
3:
addl2 %r6,%r1
addl2 %r6,%r3
movzwl $65535,%r0
jbr 5f
4:
subl2 %r0,%r6
subl2 %r0,%r1
subl2 %r0,%r3
movc3 %r0,(%r1),(%r3)
movzwl $65535,%r0
subl2 %r0,%r1
subl2 %r0,%r3
5:
cmpl %r6,%r0
jgtr 4b
subl2 %r6,%r1
subl2 %r6,%r3
movc3 %r6,(%r1),(%r3)
ret
END(bcopy)