1/* $NetBSD: setjmp.h,v 1.6 2024/05/06 07:29:30 skrll Exp $ */
2
3/*
4 * machine/setjmp.h: machine dependent setjmp-related information.
5 */
6
7#define _JBLEN 64 /* size, in longs, of a jmp_buf */
8
9/*
10 * NOTE: The internal structure of a jmp_buf is *PRIVATE*
11 * This information is provided as there is software
12 * that fiddles with this with obtain the stack pointer
13 * (yes really ! and it's commercial !).
14 *
15 * Description of the setjmp buffer
16 *
17 * Word Field Comment
18 * 0 magic number (dependent on creator)
19 * 13 fpscr vfp status control register
20 * 14 r4 register 4
21 * 15 r5 register 5
22 * 16 r6 register 6
23 * 17 r7 register 7
24 * 18 r8 register 8
25 * 19 r9 register 9
26 * 20 r10 register 10 (sl)
27 * 21 r11 register 11 (fp)
28 * 22 r12 register 12 (ip)
29 * 23 r13 register 13 (sp)
30 * 24 r14 register 14 (lr)
31 * 25 signal mask (dependent on magic)
32 * 26 (con't)
33 * 27 (con't)
34 * 28 (con't)
35 * 32-33 d8 (vfp register d8)
36 * 34-35 d9 (vfp register d9)
37 * 36-37 d10 (vfp register d10)
38 * 38-39 d11 (vfp register d11)
39 * 40-41 d12 (vfp register d12)
40 * 42-43 d13 (vfp register d13)
41 * 44-45 d14 (vfp register d14)
42 * 46-47 d15 (vfp register d15)
43 *
44 * The magic number number identifies the jmp_buf and
45 * how the buffer was created as well as providing
46 * a sanity check
47 *
48 * A side note I should mention - Please do not tamper
49 * with the floating point fields. While they are
50 * always saved and restored at the moment this cannot
51 * be guaranteed especially if the compiler happens
52 * to be generating soft-float code so no fp
53 * registers will be used.
54 *
55 * Whilst this can be seen as encouraging people to
56 * use the setjmp buffer in this way I think that it
57 * is for the best then, if changes occur, compiles will
58 * break rather than just having new builds falling over
59 * mysteriously.
60 */
61
62#define _JB_MAGIC__SETJMP 0x4278f500
63#define _JB_MAGIC_SETJMP 0x4278f501
64#define _JB_MAGIC__SETJMP_VFP 0x4278f502
65#define _JB_MAGIC_SETJMP_VFP 0x4278f503
66
67/* Valid for all jmp_buf's */
68
69#define _JB_MAGIC 0
70#define _JB_REG_FPSCR 13
71#define _JB_REG_R4 14
72#define _JB_REG_R5 15
73#define _JB_REG_R6 16
74#define _JB_REG_R7 17
75#define _JB_REG_R8 18
76#define _JB_REG_R9 19
77#define _JB_REG_R10 20
78#define _JB_REG_R11 21
79#define _JB_REG_R12 22
80#define _JB_REG_R13 23
81#define _JB_REG_R14 24
82
83/* Only valid with the _JB_MAGIC_SETJMP magic */
84
85#define _JB_SIGMASK 25
86
87#define _JB_REG_D8 32
88#define _JB_REG_D9 34
89#define _JB_REG_D10 36
90#define _JB_REG_D11 38
91#define _JB_REG_D12 40
92#define _JB_REG_D13 42
93#define _JB_REG_D14 44
94#define _JB_REG_D15 46