xref: /freebsd/lib/libc/powerpc/gen/_setjmp.S (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
1/*-
2 * Copyright (c) 2002 Peter Grehan.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26/*      $NetBSD: _setjmp.S,v 1.1 1997/03/29 20:55:53 thorpej Exp $      */
27
28#include <machine/asm.h>
29__FBSDID("$FreeBSD$");
30
31/*
32 * C library -- _setjmp, _longjmp
33 *
34 *      _longjmp(a,v)
35 * will generate a "return(v?v:1)" from the last call to
36 *      _setjmp(a)
37 * by restoring registers from the stack.
38 * The previous signal state is NOT restored.
39 *
40 * jmpbuf layout:
41 *     +------------+
42 *     |   unused   |
43 *     +------------+
44 *     |   unused   |
45 *     |            |
46 *     | (4 words)  |
47 *     |            |
48 *     +------------+
49 *     | saved regs |
50 *     |    ...     |
51 */
52
53ENTRY(_setjmp)
54	mflr	%r11
55	mfcr	%r12
56	mr	%r10,%r1
57	mr	%r9,%r2
58	stmw	%r9,20(%r3)
59	li	%r3,0
60	blr
61
62ENTRY(_longjmp)
63	lmw	%r9,20(%r3)
64	mtlr	%r11
65	mtcr	%r12
66	mr	%r2,%r9
67	mr	%r1,%r10
68	or.	%r3,%r4,%r4
69	bnelr
70	li	%r3,1
71	blr
72