1 /*
2  * Mapping of DWARF debug register numbers into register names.
3  *
4  * Copyright (C) 2010 Will Deacon, ARM Ltd.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #include <stddef.h>
12 #include <dwarf-regs.h>
13 
14 struct pt_regs_dwarfnum {
15 	const char *name;
16 	unsigned int dwarfnum;
17 };
18 
19 #define STR(s) #s
20 #define REG_DWARFNUM_NAME(r, num) {.name = r, .dwarfnum = num}
21 #define GPR_DWARFNUM_NAME(num) \
22 	{.name = STR(%r##num), .dwarfnum = num}
23 #define REG_DWARFNUM_END {.name = NULL, .dwarfnum = 0}
24 
25 /*
26  * Reference:
27  * http://infocenter.arm.com/help/topic/com.arm.doc.ihi0040a/IHI0040A_aadwarf.pdf
28  */
29 static const struct pt_regs_dwarfnum regdwarfnum_table[] = {
30 	GPR_DWARFNUM_NAME(0),
31 	GPR_DWARFNUM_NAME(1),
32 	GPR_DWARFNUM_NAME(2),
33 	GPR_DWARFNUM_NAME(3),
34 	GPR_DWARFNUM_NAME(4),
35 	GPR_DWARFNUM_NAME(5),
36 	GPR_DWARFNUM_NAME(6),
37 	GPR_DWARFNUM_NAME(7),
38 	GPR_DWARFNUM_NAME(8),
39 	GPR_DWARFNUM_NAME(9),
40 	GPR_DWARFNUM_NAME(10),
41 	REG_DWARFNUM_NAME("%fp", 11),
42 	REG_DWARFNUM_NAME("%ip", 12),
43 	REG_DWARFNUM_NAME("%sp", 13),
44 	REG_DWARFNUM_NAME("%lr", 14),
45 	REG_DWARFNUM_NAME("%pc", 15),
46 	REG_DWARFNUM_END,
47 };
48 
49 /**
50  * get_arch_regstr() - lookup register name from it's DWARF register number
51  * @n:	the DWARF register number
52  *
53  * get_arch_regstr() returns the name of the register in struct
54  * regdwarfnum_table from it's DWARF register number. If the register is not
55  * found in the table, this returns NULL;
56  */
get_arch_regstr(unsigned int n)57 const char *get_arch_regstr(unsigned int n)
58 {
59 	const struct pt_regs_dwarfnum *roff;
60 	for (roff = regdwarfnum_table; roff->name != NULL; roff++)
61 		if (roff->dwarfnum == n)
62 			return roff->name;
63 	return NULL;
64 }
65