xref: /minix3/lib/libc/arch/m68k/string/memccpy.S (revision 0a6a1f1d05b60e214de2f05a7310ddd1f0e590e7)
1*0a6a1f1dSLionel Sambuc/*	$NetBSD: memccpy.S,v 1.5 2014/03/18 18:20:37 riastradh Exp $	*/
22fe8fb19SBen Gras
32fe8fb19SBen Gras/*
42fe8fb19SBen Gras * Copyright (C) 1999 Scott Reynolds.  All rights reserved.
52fe8fb19SBen Gras *
62fe8fb19SBen Gras * Redistribution and use in source and binary forms, with or without
72fe8fb19SBen Gras * modification, are permitted provided that the following conditions
82fe8fb19SBen Gras * are met:
92fe8fb19SBen Gras * 1. Redistributions of source code must retain the above copyright
102fe8fb19SBen Gras *    notice, this list of conditions and the following disclaimer.
112fe8fb19SBen Gras * 2. Redistributions in binary form must reproduce the above copyright
122fe8fb19SBen Gras *    notice, this list of conditions and the following disclaimer in the
132fe8fb19SBen Gras *    documentation and/or other materials provided with the distribution.
142fe8fb19SBen Gras * 3. The name of the author may not be used to endorse or promote products
152fe8fb19SBen Gras *    derived from this software without specific prior written permission.
162fe8fb19SBen Gras *
172fe8fb19SBen Gras * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
182fe8fb19SBen Gras * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
192fe8fb19SBen Gras * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
202fe8fb19SBen Gras * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
212fe8fb19SBen Gras * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
222fe8fb19SBen Gras * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
232fe8fb19SBen Gras * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
242fe8fb19SBen Gras * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
252fe8fb19SBen Gras * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
262fe8fb19SBen Gras * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
272fe8fb19SBen Gras */
282fe8fb19SBen Gras
292fe8fb19SBen Gras#include <machine/asm.h>
302fe8fb19SBen Gras
312fe8fb19SBen Gras#if defined(LIBC_SCCS) && !defined(lint)
32*0a6a1f1dSLionel Sambuc	RCSID("$NetBSD: memccpy.S,v 1.5 2014/03/18 18:20:37 riastradh Exp $")
332fe8fb19SBen Gras#endif /* LIBC_SCCS and not lint */
342fe8fb19SBen Gras
352fe8fb19SBen GrasENTRY(memccpy)
3684d9c625SLionel Sambuc	movl	16(%sp),%d0		| count
372fe8fb19SBen Gras	jeq	Lmcbail			| nothing to do
382fe8fb19SBen Gras
3984d9c625SLionel Sambuc	movl	4(%sp),%a0		| a0 = toaddr
4084d9c625SLionel Sambuc#ifndef __mcoldfire__
412fe8fb19SBen Gras	subql	#1,%d0			|   prepare count for DBcc loop
4284d9c625SLionel Sambuc#endif
4384d9c625SLionel Sambuc	movl	8(%sp),%a1		| a1 = fromaddr
4484d9c625SLionel Sambuc	movl	12(%sp),%d1		| d1 = terminator
452fe8fb19SBen Gras	jeq	Lmcloop			|   handle ASCII NUL specially
462fe8fb19SBen Gras
4784d9c625SLionel Sambuc	movl	%d2,-(%sp)		| save scratch register
482fe8fb19SBen GrasLmcnzloop:
4984d9c625SLionel Sambuc	movb	(%a1)+,%d2		| move a byte
5084d9c625SLionel Sambuc	movb	%d2,(%a0)+
512fe8fb19SBen Gras	cmpb	%d2,%d1			| found the terminator?
5284d9c625SLionel Sambuc#ifndef __mcoldfire__
532fe8fb19SBen Gras	dbeq	%d0,Lmcnzloop		| if not, keep transferring,
5484d9c625SLionel Sambuc#endif
552fe8fb19SBen Gras	jeq	Lmcnzdone		|   otherwise done
5684d9c625SLionel Sambuc#ifdef __mcoldfire__
5784d9c625SLionel Sambuc	subql	#1,%d0
5884d9c625SLionel Sambuc	jne	Lmcnzloop
5984d9c625SLionel Sambuc#else
602fe8fb19SBen Gras	clrw	%d0			| check to see if more to do
612fe8fb19SBen Gras	subql	#1,%d0
622fe8fb19SBen Gras	jcc	Lmcnzloop		| yes, keep going...
6384d9c625SLionel Sambuc#endif
642fe8fb19SBen Gras
6584d9c625SLionel Sambuc	movl	(%sp)+,%d2		| restore scratch register
662fe8fb19SBen Gras	movql	#0,%d0			| no terminator found, return NULL
672fe8fb19SBen Gras#ifdef __SVR4_ABI__
682fe8fb19SBen Gras	movl	%d0,%a0			| XXX maybe use lea to avoid stall?
692fe8fb19SBen Gras#endif
702fe8fb19SBen Gras	rts
712fe8fb19SBen Gras
722fe8fb19SBen GrasLmcloop:
7384d9c625SLionel Sambuc	movb	(%a1)+,(%a0)+		| move a byte; was it NUL?
7484d9c625SLionel Sambuc#ifndef __mcoldfire__
752fe8fb19SBen Gras	dbeq	%d0,Lmcloop		| if not, keep transferring,
7684d9c625SLionel Sambuc#endif
772fe8fb19SBen Gras	jeq	Lmcdone			|   otherwise done
7884d9c625SLionel Sambuc#ifdef __mcoldfire__
7984d9c625SLionel Sambuc	subql	#1,%d0
8084d9c625SLionel Sambuc	jne	Lmcloop
8184d9c625SLionel Sambuc#else
822fe8fb19SBen Gras	clrw	%d0			| check to see if more to do
832fe8fb19SBen Gras	subql	#1,%d0
842fe8fb19SBen Gras	jcc	Lmcloop			| yes, keep going...
8584d9c625SLionel Sambuc#endif
862fe8fb19SBen Gras					| Note: %d0 is now -1!
872fe8fb19SBen Gras	movql	#0,%d0			| no terminator found, return NULL
882fe8fb19SBen GrasLmcbail:
892fe8fb19SBen Gras#ifdef __SVR4_ABI__
902fe8fb19SBen Gras	movl	%d0,%a0			| XXX maybe use lea to avoid stall?
912fe8fb19SBen Gras#endif
922fe8fb19SBen Gras	rts
932fe8fb19SBen Gras
942fe8fb19SBen GrasLmcnzdone:
9584d9c625SLionel Sambuc	movl	(%sp)+,%d2		| restore scratch register
962fe8fb19SBen GrasLmcdone:
972fe8fb19SBen Gras	movl	%a0,%d0
982fe8fb19SBen Gras	rts
9984d9c625SLionel SambucEND(memccpy)
100