1/*	$NetBSD: swapcontext.S,v 1.3 2008/04/28 20:22:58 martin Exp $	*/
2
3/*-
4 * Copyright (c) 2003 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Matt Thomas.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include "SYS.h"
33
34#ifdef LIBC_SCCS
35RCSID("$NetBSD$")
36#endif
37
38ENTRY(swapcontext, 0)
39	clrl	%r0			/* assume getcontext succeeds */
40	chmk	$SYS_getcontext		/* getcontext(oucp) */
41	jcc	1f
42	jmp	CERROR+2		/* something bad happened */
43
441:	movl	4(%ap),%r0		/* get oucp */
45	addl3	(%ap),$(5+1),%r1	/* size of callframe + arglist (LW) */
46	bbs	$13,6(%fp),2f		/* was this a CALLG? */
47	movl	$5,%r1			/* size of callframe (in LW) */
482:	movl	8(%fp),(36+12*4)(%r0)		/* restore AP */
49	moval	(%sp)[%r1],(36+13*4)(%r0)	/* restore SP */
50	movq	12(%fp),(36+14*4)(%r0)		/* restore FP + PC */
51
52	pushl	8(%ap)
53	calls	$1,_C_LABEL(setcontext) /* setcontext(ucp) */
54	ret
55END(swapcontext)
56