1/*	$OpenBSD: setjmp.h,v 1.2 2023/04/11 00:45:07 jsg Exp $	*/
2/*	$NetBSD: setjmp.h,v 1.2 2001/08/25 14:45:59 bjh21 Exp $	*/
3
4/*
5 * machine/setjmp.h: machine dependent setjmp-related information.
6 */
7
8#define	_JBLEN	64		/* size, in longs, of a jmp_buf */
9
10/*
11 * NOTE: The internal structure of a jmp_buf is *PRIVATE*
12 *       This information is provided as there is software
13 *       that fiddles with this with obtain the stack pointer
14 *	 (yes really ! and it's commercial !).
15 *
16 * Description of the setjmp buffer
17 *
18 * word  0	magic number	(dependant on creator)
19 *       1 -  3	f4		fp register 4
20 *	 4 -  6	f5		fp register 5
21 *	 7 -  9 f6		fp register 6
22 *	10 - 12	f7		fp register 7
23 *	13	fpsr		fp status register
24 *	14	r4		register 4
25 *	15	r5		register 5
26 *	16	r6		register 6
27 *	17	r7		register 7
28 *	18	r8		register 8
29 *	19	r9		register 9
30 *	20	r10		register 10 (sl)
31 *	21	r11		register 11 (fp)
32 *	22	r12		register 12 (ip)
33 *	23	r13		register 13 (sp)
34 *	24	r14		register 14 (lr)
35 *	25	signal mask	(dependant on magic)
36 *	26	(con't)
37 *	27	(con't)
38 *	28	(con't)
39 *
40 * The magic number identifies the jmp_buf and
41 * how the buffer was created as well as providing
42 * a sanity check.
43 *
44 * A side note I should mention - please do not tamper
45 * with the floating point fields. While they are
46 * always saved and restored at the moment this cannot
47 * be guaranteed especially if the compiler happens
48 * to be generating soft-float code so no fp
49 * registers will be used.
50 *
51 * Whilst this can be seen an encouraging people to
52 * use the setjmp buffer in this way I think that it
53 * is for the best then if changes occur compiles will
54 * break rather than just having new builds falling over
55 * mysteriously.
56 */
57
58#define _JB_MAGIC__SETJMP	0x4278f500
59#define _JB_MAGIC_SETJMP	0x4278f501
60
61/* Valid for all jmp_buf's */
62
63#define _JB_MAGIC		 0
64#define _JB_REG_F4		 1
65#define _JB_REG_F5		 4
66#define _JB_REG_F6		 7
67#define _JB_REG_F7		10
68#define _JB_REG_FPSR		13
69#define _JB_REG_R4		14
70#define _JB_REG_R5		15
71#define _JB_REG_R6		16
72#define _JB_REG_R7		17
73#define _JB_REG_R8		18
74#define _JB_REG_R9		19
75#define _JB_REG_R10		20
76#define _JB_REG_R11		21
77#define _JB_REG_R12		22
78#define _JB_REG_R13		23
79#define _JB_REG_R14		24
80
81/* Only valid with the _JB_MAGIC_SETJMP magic */
82
83#define _JB_SIGMASK		25
84