xref: /linux/tools/perf/util/dwarf-regs.c (revision d3ab52c31efab9e8a29b8fc1ae4c09ab41e0cf84)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * dwarf-regs.c : Mapping of DWARF debug register numbers into register names.
4  *
5  * Written by: Masami Hiramatsu <mhiramat@kernel.org>
6  */
7 
8 #include <stdlib.h>
9 #include <string.h>
10 #include <debug.h>
11 #include <dwarf-regs.h>
12 #include <elf.h>
13 #include <errno.h>
14 #include <linux/kernel.h>
15 
16 /* Define const char * {arch}_register_tbl[] */
17 #define DEFINE_DWARF_REGSTR_TABLE
18 #include "../arch/x86/include/dwarf-regs-table.h"
19 #include "../arch/arm/include/dwarf-regs-table.h"
20 #include "../arch/arm64/include/dwarf-regs-table.h"
21 #include "../arch/sh/include/dwarf-regs-table.h"
22 #include "../arch/powerpc/include/dwarf-regs-table.h"
23 #include "../arch/riscv/include/dwarf-regs-table.h"
24 #include "../arch/s390/include/dwarf-regs-table.h"
25 #include "../arch/sparc/include/dwarf-regs-table.h"
26 #include "../arch/xtensa/include/dwarf-regs-table.h"
27 #include "../arch/mips/include/dwarf-regs-table.h"
28 #include "../arch/loongarch/include/dwarf-regs-table.h"
29 
30 #define __get_dwarf_regstr(tbl, n) (((n) < ARRAY_SIZE(tbl)) ? (tbl)[(n)] : NULL)
31 
32 /* Return architecture dependent register string (for kprobe-tracer) */
33 const char *get_dwarf_regstr(unsigned int n, unsigned int machine, unsigned int flags)
34 {
35 	if (machine == EM_NONE) {
36 		/* Generic arch - use host arch */
37 		machine = EM_HOST;
38 	}
39 	switch (machine) {
40 	case EM_386:
41 		return __get_dwarf_regstr(x86_32_regstr_tbl, n);
42 	case EM_X86_64:
43 		return __get_dwarf_regstr(x86_64_regstr_tbl, n);
44 	case EM_ARM:
45 		return __get_dwarf_regstr(arm_regstr_tbl, n);
46 	case EM_AARCH64:
47 		return __get_dwarf_regstr(aarch64_regstr_tbl, n);
48 	case EM_CSKY:
49 		return get_csky_regstr(n, flags);
50 	case EM_SH:
51 		return __get_dwarf_regstr(sh_regstr_tbl, n);
52 	case EM_S390:
53 		return __get_dwarf_regstr(s390_regstr_tbl, n);
54 	case EM_PPC:
55 	case EM_PPC64:
56 		return __get_dwarf_regstr(powerpc_regstr_tbl, n);
57 	case EM_RISCV:
58 		return __get_dwarf_regstr(riscv_regstr_tbl, n);
59 	case EM_SPARC:
60 	case EM_SPARCV9:
61 		return __get_dwarf_regstr(sparc_regstr_tbl, n);
62 	case EM_XTENSA:
63 		return __get_dwarf_regstr(xtensa_regstr_tbl, n);
64 	case EM_MIPS:
65 		return __get_dwarf_regstr(mips_regstr_tbl, n);
66 	case EM_LOONGARCH:
67 		return __get_dwarf_regstr(loongarch_regstr_tbl, n);
68 	default:
69 		pr_err("ELF MACHINE %x is not supported.\n", machine);
70 	}
71 	return NULL;
72 }
73 
74 /* Return DWARF register number from architecture register name */
75 int get_dwarf_regnum(const char *name, unsigned int machine, unsigned int flags __maybe_unused)
76 {
77 	char *regname = strdup(name);
78 	int reg = -1;
79 	char *p;
80 
81 	if (regname == NULL)
82 		return -EINVAL;
83 
84 	/* For convenience, remove trailing characters */
85 	p = strpbrk(regname, " ,)");
86 	if (p)
87 		*p = '\0';
88 
89 	if (machine == EM_NONE) {
90 		/* Generic arch - use host arch */
91 		machine = EM_HOST;
92 	}
93 	switch (machine) {
94 	case EM_X86_64:
95 		reg = __get_dwarf_regnum_x86_64(name);
96 		break;
97 	case EM_386:
98 		reg = __get_dwarf_regnum_i386(name);
99 		break;
100 	default:
101 		pr_err("ELF MACHINE %x is not supported.\n", machine);
102 	}
103 	free(regname);
104 	return reg;
105 }
106 
107 static int get_libdw_frame_nregs(unsigned int machine, unsigned int flags __maybe_unused)
108 {
109 	switch (machine) {
110 	case EM_X86_64:
111 		return 17;
112 	case EM_386:
113 		return 9;
114 	case EM_ARM:
115 		return 16;
116 	case EM_AARCH64:
117 		return 97;
118 	case EM_CSKY:
119 		return 38;
120 	case EM_S390:
121 		return 32;
122 	case EM_PPC:
123 	case EM_PPC64:
124 		return 145;
125 	case EM_RISCV:
126 		return 66;
127 	case EM_SPARC:
128 	case EM_SPARCV9:
129 		return 103;
130 	case EM_LOONGARCH:
131 		return 74;
132 	default:
133 		return 0;
134 	}
135 }
136 
137 int get_dwarf_regnum_for_perf_regnum(int perf_regnum, unsigned int machine,
138 				     unsigned int flags, bool only_libdw_supported)
139 {
140 	int reg;
141 
142 	switch (machine) {
143 	case EM_X86_64:
144 		reg = __get_dwarf_regnum_for_perf_regnum_x86_64(perf_regnum);
145 		break;
146 	case EM_386:
147 		reg = __get_dwarf_regnum_for_perf_regnum_i386(perf_regnum);
148 		break;
149 	default:
150 		pr_err("ELF MACHINE %x is not supported.\n", machine);
151 		return -ENOENT;
152 	}
153 	if (reg >= 0 && only_libdw_supported) {
154 		int nregs = get_libdw_frame_nregs(machine, flags);
155 
156 		if (reg >= nregs)
157 			reg = -ENOENT;
158 	}
159 	return reg;
160 }
161