xref: /minix3/lib/libc/arch/aarch64/gen/_setjmp.S (revision 0a6a1f1d05b60e214de2f05a7310ddd1f0e590e7)
1/* $NetBSD: _setjmp.S,v 1.1 2014/08/10 05:47:36 matt Exp $ */
2
3/*-
4 * Copyright (c) 2014 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 of 3am Software Foundry.
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 <machine/asm.h>
33#include "assym.h"
34
35/*
36 * C library -- _setjmp, _longjmp
37 *
38 *	_longjmp(a, v)
39 * will generate a "return v;" from the last call to
40 *	_setjmp(a)
41 * by restoring registers from the stack.
42 * The previous signal state is NOT restored.
43 *
44 * Note: x0 is the return value
45 */
46	.section	.rodata.cst8,"aM",@progbits,8
47	.align	3
48.L_MAGIC:
49	.xword	_JB_MAGIC_AARCH64__SETJMP
50
51ENTRY(_setjmp)
52	adrp	x7, .L_MAGIC
53	ldr	x7, [x7, #:lo12:.L_MAGIC]
54
55	mov	x3, sp
56
57	stp	x7, x3, [x0, #_JB_MAGIC]
58
59	stp	x19, x20, [x0, #_JB_X19]
60	stp	x21, x22, [x0, #_JB_X21]
61	stp	x23, x24, [x0, #_JB_X23]
62	stp	x25, x26, [x0, #_JB_X25]
63	stp	x27, x28, [x0, #_JB_X27]
64	stp	x29, x30, [x0, #_JB_X29]
65
66	mrs	x5, tpidr_el0
67	str	x5, [x0, #_JB_TPIDR]
68
69	stp	d8,  d9,  [x0, #_JB_D8]
70	stp	d10, d11, [x0, #_JB_D10]
71	stp	d12, d13, [x0, #_JB_D12]
72	stp	d14, d15, [x0, #_JB_D14]
73
74        mov	x0, xzr
75        ret
76END(_setjmp)
77
78ENTRY(_longjmp)
79	adrp	x7, .L_MAGIC
80	ldr	x7, [x7, #:lo12:.L_MAGIC]
81
82	ldp	x2, x3, [x0, #_JB_MAGIC]
83	ldp	x4, x5, [x0, #_JB_X29]
84
85	cbz	x3, .Lbotch
86	cbz	x4, .Lbotch
87	cbz	x5, .Lbotch
88	cmp	x2, x7
89	b.ne	.Lbotch
90
91	ldp	x19, x20, [x0, #_JB_X19]
92	ldp	x21, x22, [x0, #_JB_X21]
93	ldp	x23, x24, [x0, #_JB_X23]
94	ldp	x25, x26, [x0, #_JB_X25]
95	ldp	x27, x28, [x0, #_JB_X27]
96
97	ldr	x5, [x0, #_JB_TPIDR]
98	msr	tpidr_el0, x5
99
100	ldp	d8,  d9,  [x0, #_JB_D8]
101	ldp	d10, d11, [x0, #_JB_D10]
102	ldp	d12, d13, [x0, #_JB_D12]
103	ldp	d14, d15, [x0, #_JB_D14]
104
105	mov	sp, x3
106	mov	x29, x4
107	mov	x30, x5
108
109        mov	x0, x1
110        ret
111
112	/* validation failed, die die die. */
113.Lbotch:
114	bl	_C_LABEL(longjmperror)
115	bl	_C_LABEL(abort)
1161:	b	1b		/* Cannot get here */
117END(_longjmp)
118