summaryrefslogtreecommitdiff
path: root/lib/libc/compat/arch/arm/gen/compat_setjmp.S
blob: 10769c3b1614ee63bfe2b2c0c17cfa8039618b61 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
/*	$NetBSD: compat_setjmp.S,v 1.5 2020/12/05 11:18:21 skrll Exp $	*/

/*
 * Copyright (c) 1997 Mark Brinicombe
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Mark Brinicombe
 * 4. 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 AUTHOR 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 AUTHOR 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.
 */

#include <machine/asm.h>
#include <machine/setjmp.h>

/*
 * C library -- setjmp, longjmp
 *
 *	longjmp(a,v)
 * will generate a "return(v)" from the last call to
 *	setjmp(a)
 * by restoring registers from the stack.
 * The previous signal state is restored.
 */

ENTRY(setjmp)
	/* Block all signals and retrieve the old signal mask */
	push	{r0, lr}
	movs	r0, #0x00000000

	bl	PLT_SYM(_C_LABEL(sigblock))
	mov	r1, r0

	/* Store signal mask */
	str	r1, [r0, #(_JB_SIGMASK * 4)]

	ldr	r1, .Lsetjmp_magic
	str	r1, [r0]

	/* Store integer registers */
	adds	r0, r0, #(_JB_REG_R4 * 4)
#ifdef __thumb__
#ifdef _ARM_ARCH_7
	stmia	r0!, {r4-r12}
	str	sp, [r0, #0]
	str	lr, [r0, #4]
#else
	stmia	r0!, {r4-r7}
	mov	r2, r8
	mov	r3, r9
	stmia	r0!, {r2-r3}
	mov	r1, r10
	mov	r2, r11
	mov	r3, r12
	stmia	r0!, {r1-r3}
	mov	r2, sp
	mov	r3, lr
	stmia	r0!, {r2-r3}
#endif
#else
	stmia	r0, {r4-lr}
#endif
	movs	r0, #0
	pop	{r3, pc}
END(setjmp)

ENTRY(longjmp)
	ldr	r2, .Lsetjmp_magic
	ldr	r3, [r0]
	cmp	r2, r3
	bne	botch

	/* Fetch signal mask */
	ldr	r2, [r0, #(_JB_SIGMASK * 4)]

	/* Set signal mask */
	push	{r0, r1}	/* don't care about lr */

	mov	r0, r2
	bl	PLT_SYM(_C_LABEL(sigsetmask))

	pop	{r0, r1}

	/* Restore integer registers */
	adds	r0, r0, #(_JB_REG_R4 * 4)
#if !defined(__thumb__) || defined(_ARM_ARCH_7)
	ldmia	r0!, {r4-r12}
#else
	ldmia	r0!, {r4-r7}
	ldmia	r0!, {r2-r3}
	mov	r8, r2
	mov	r9, r3
	ldmia	r0!, {r1-r3}
	mov	r10, r2
	mov	r11, r3
	ldmia	r0!, {r2}
	mov	r12, r2
#endif

	ldmia	r0!, {r2-r3}	/* r2 = sp, r3 = lr */

	/* Validate sp */
	cmp	r2, #0
	beq	botch
	mov	sp, r2

	/* Validate lr */
	cmp	r3, #0
	beq	botch
	mov	lr, r3

	/* Set return value */
	mov	r0, r1
	cmp	r0, #0
#ifdef __thumb__
	bne	1f
	movs	r0, #1
1:
#else
	moveq	r0, #1
#endif
	RET

	/* validation failed, die die die. */
botch:
	bl	PLT_SYM(_C_LABEL(longjmperror))
	bl	PLT_SYM(_C_LABEL(abort))
2:	b	2b		/* Cannot get here */

	.align	0
.Lsetjmp_magic:
	.word	_JB_MAGIC_SETJMP
END(longjmp)