1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Mapping of DWARF debug register numbers into register names.
4 *
5 * Copyright (C) 2010 Will Deacon, ARM Ltd.
6 */
7
8 #include <errno.h>
9 #include <stddef.h>
10 #include <string.h>
11 #include <dwarf-regs.h>
12 #include <linux/ptrace.h> /* for struct user_pt_regs */
13 #include <linux/stringify.h>
14
15 struct pt_regs_dwarfnum {
16 const char *name;
17 unsigned int dwarfnum;
18 };
19
20 #define REG_DWARFNUM_NAME(r, num) {.name = r, .dwarfnum = num}
21 #define GPR_DWARFNUM_NAME(num) \
22 {.name = __stringify(%x##num), .dwarfnum = num}
23 #define REG_DWARFNUM_END {.name = NULL, .dwarfnum = 0}
24 #define DWARFNUM2OFFSET(index) \
25 (index * sizeof((struct user_pt_regs *)0)->regs[0])
26
27 /*
28 * Reference:
29 * http://infocenter.arm.com/help/topic/com.arm.doc.ihi0057b/IHI0057B_aadwarf64.pdf
30 */
31 static const struct pt_regs_dwarfnum regdwarfnum_table[] = {
32 GPR_DWARFNUM_NAME(0),
33 GPR_DWARFNUM_NAME(1),
34 GPR_DWARFNUM_NAME(2),
35 GPR_DWARFNUM_NAME(3),
36 GPR_DWARFNUM_NAME(4),
37 GPR_DWARFNUM_NAME(5),
38 GPR_DWARFNUM_NAME(6),
39 GPR_DWARFNUM_NAME(7),
40 GPR_DWARFNUM_NAME(8),
41 GPR_DWARFNUM_NAME(9),
42 GPR_DWARFNUM_NAME(10),
43 GPR_DWARFNUM_NAME(11),
44 GPR_DWARFNUM_NAME(12),
45 GPR_DWARFNUM_NAME(13),
46 GPR_DWARFNUM_NAME(14),
47 GPR_DWARFNUM_NAME(15),
48 GPR_DWARFNUM_NAME(16),
49 GPR_DWARFNUM_NAME(17),
50 GPR_DWARFNUM_NAME(18),
51 GPR_DWARFNUM_NAME(19),
52 GPR_DWARFNUM_NAME(20),
53 GPR_DWARFNUM_NAME(21),
54 GPR_DWARFNUM_NAME(22),
55 GPR_DWARFNUM_NAME(23),
56 GPR_DWARFNUM_NAME(24),
57 GPR_DWARFNUM_NAME(25),
58 GPR_DWARFNUM_NAME(26),
59 GPR_DWARFNUM_NAME(27),
60 GPR_DWARFNUM_NAME(28),
61 GPR_DWARFNUM_NAME(29),
62 REG_DWARFNUM_NAME("%lr", 30),
63 REG_DWARFNUM_NAME("%sp", 31),
64 REG_DWARFNUM_END,
65 };
66
67 /**
68 * get_arch_regstr() - lookup register name from it's DWARF register number
69 * @n: the DWARF register number
70 *
71 * get_arch_regstr() returns the name of the register in struct
72 * regdwarfnum_table from it's DWARF register number. If the register is not
73 * found in the table, this returns NULL;
74 */
get_arch_regstr(unsigned int n)75 const char *get_arch_regstr(unsigned int n)
76 {
77 const struct pt_regs_dwarfnum *roff;
78 for (roff = regdwarfnum_table; roff->name != NULL; roff++)
79 if (roff->dwarfnum == n)
80 return roff->name;
81 return NULL;
82 }
83
regs_query_register_offset(const char * name)84 int regs_query_register_offset(const char *name)
85 {
86 const struct pt_regs_dwarfnum *roff;
87
88 for (roff = regdwarfnum_table; roff->name != NULL; roff++)
89 if (!strcmp(roff->name, name))
90 return DWARFNUM2OFFSET(roff->dwarfnum);
91 return -EINVAL;
92 }
93