1 /*
2  * Mapping of DWARF debug register numbers into register names.
3  *
4  * Copyright (C) 2010 Ian Munsie, IBM Corporation.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 
12 #include <stddef.h>
13 #include <errno.h>
14 #include <string.h>
15 #include <dwarf-regs.h>
16 #include <linux/ptrace.h>
17 #include <linux/kernel.h>
18 #include <linux/stringify.h>
19 #include "util.h"
20 
21 struct pt_regs_dwarfnum {
22 	const char *name;
23 	unsigned int dwarfnum;
24 	unsigned int ptregs_offset;
25 };
26 
27 #define REG_DWARFNUM_NAME(r, num)					\
28 		{.name = __stringify(%)__stringify(r), .dwarfnum = num,			\
29 		.ptregs_offset = offsetof(struct pt_regs, r)}
30 #define GPR_DWARFNUM_NAME(num)						\
31 		{.name = __stringify(%gpr##num), .dwarfnum = num,		\
32 		.ptregs_offset = offsetof(struct pt_regs, gpr[num])}
33 #define REG_DWARFNUM_END {.name = NULL, .dwarfnum = 0, .ptregs_offset = 0}
34 
35 /*
36  * Reference:
37  * http://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi-1.9.html
38  */
39 static const struct pt_regs_dwarfnum regdwarfnum_table[] = {
40 	GPR_DWARFNUM_NAME(0),
41 	GPR_DWARFNUM_NAME(1),
42 	GPR_DWARFNUM_NAME(2),
43 	GPR_DWARFNUM_NAME(3),
44 	GPR_DWARFNUM_NAME(4),
45 	GPR_DWARFNUM_NAME(5),
46 	GPR_DWARFNUM_NAME(6),
47 	GPR_DWARFNUM_NAME(7),
48 	GPR_DWARFNUM_NAME(8),
49 	GPR_DWARFNUM_NAME(9),
50 	GPR_DWARFNUM_NAME(10),
51 	GPR_DWARFNUM_NAME(11),
52 	GPR_DWARFNUM_NAME(12),
53 	GPR_DWARFNUM_NAME(13),
54 	GPR_DWARFNUM_NAME(14),
55 	GPR_DWARFNUM_NAME(15),
56 	GPR_DWARFNUM_NAME(16),
57 	GPR_DWARFNUM_NAME(17),
58 	GPR_DWARFNUM_NAME(18),
59 	GPR_DWARFNUM_NAME(19),
60 	GPR_DWARFNUM_NAME(20),
61 	GPR_DWARFNUM_NAME(21),
62 	GPR_DWARFNUM_NAME(22),
63 	GPR_DWARFNUM_NAME(23),
64 	GPR_DWARFNUM_NAME(24),
65 	GPR_DWARFNUM_NAME(25),
66 	GPR_DWARFNUM_NAME(26),
67 	GPR_DWARFNUM_NAME(27),
68 	GPR_DWARFNUM_NAME(28),
69 	GPR_DWARFNUM_NAME(29),
70 	GPR_DWARFNUM_NAME(30),
71 	GPR_DWARFNUM_NAME(31),
72 	REG_DWARFNUM_NAME(msr,   66),
73 	REG_DWARFNUM_NAME(ctr,   109),
74 	REG_DWARFNUM_NAME(link,  108),
75 	REG_DWARFNUM_NAME(xer,   101),
76 	REG_DWARFNUM_NAME(dar,   119),
77 	REG_DWARFNUM_NAME(dsisr, 118),
78 	REG_DWARFNUM_END,
79 };
80 
81 /**
82  * get_arch_regstr() - lookup register name from it's DWARF register number
83  * @n:	the DWARF register number
84  *
85  * get_arch_regstr() returns the name of the register in struct
86  * regdwarfnum_table from it's DWARF register number. If the register is not
87  * found in the table, this returns NULL;
88  */
89 const char *get_arch_regstr(unsigned int n)
90 {
91 	const struct pt_regs_dwarfnum *roff;
92 	for (roff = regdwarfnum_table; roff->name != NULL; roff++)
93 		if (roff->dwarfnum == n)
94 			return roff->name;
95 	return NULL;
96 }
97 
98 int regs_query_register_offset(const char *name)
99 {
100 	const struct pt_regs_dwarfnum *roff;
101 	for (roff = regdwarfnum_table; roff->name != NULL; roff++)
102 		if (!strcmp(roff->name, name))
103 			return roff->ptregs_offset;
104 	return -EINVAL;
105 }
106