xref: /linux/tools/perf/util/dwarf-regs.c (revision bf4afc53b77aeaa48b5409da5c8da6bb4eff7f43)
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 /* Return architecture dependent register string (for kprobe-tracer) */
31 const char *get_dwarf_regstr(unsigned int n, unsigned int machine, unsigned int flags)
32 {
33 	#define __get_dwarf_regstr(tbl, n) (((n) < ARRAY_SIZE(tbl)) ? (tbl)[(n)] : NULL)
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 	#undef __get_dwarf_regstr
74 }
75 
76 static int __get_dwarf_regnum(const char *const *regstr, size_t num_regstr, const char *name)
77 {
78 	for (size_t i = 0; i < num_regstr; i++) {
79 		if (regstr[i] && !strcmp(regstr[i], name))
80 			return i;
81 	}
82 	return -ENOENT;
83 }
84 
85 /* Return DWARF register number from architecture register name */
86 int get_dwarf_regnum(const char *name, unsigned int machine, unsigned int flags)
87 {
88 	char *regname = strdup(name);
89 	int reg = -1;
90 	char *p;
91 
92 	#define _get_dwarf_regnum(tbl, name) __get_dwarf_regnum(tbl, ARRAY_SIZE(tbl), name)
93 
94 	if (regname == NULL)
95 		return -EINVAL;
96 
97 	/* For convenience, remove trailing characters */
98 	p = strpbrk(regname, " ,)");
99 	if (p)
100 		*p = '\0';
101 
102 	if (machine == EM_NONE) {
103 		/* Generic arch - use host arch */
104 		machine = EM_HOST;
105 	}
106 	switch (machine) {
107 	case EM_X86_64:
108 		reg = __get_dwarf_regnum_x86_64(name);
109 		break;
110 	case EM_386:
111 		reg = __get_dwarf_regnum_i386(name);
112 		break;
113 	case EM_ARM:
114 		reg = _get_dwarf_regnum(arm_regstr_tbl, name);
115 		break;
116 	case EM_AARCH64:
117 		reg = _get_dwarf_regnum(aarch64_regstr_tbl, name);
118 		break;
119 	case EM_CSKY:
120 		reg = __get_csky_regnum(name, flags);
121 		break;
122 	case EM_SH:
123 		reg = _get_dwarf_regnum(sh_regstr_tbl, name);
124 		break;
125 	case EM_S390:
126 		reg = _get_dwarf_regnum(s390_regstr_tbl, name);
127 		break;
128 	case EM_PPC:
129 	case EM_PPC64:
130 		reg = _get_dwarf_regnum(powerpc_regstr_tbl, name);
131 		break;
132 	case EM_RISCV:
133 		reg = _get_dwarf_regnum(riscv_regstr_tbl, name);
134 		break;
135 	case EM_SPARC:
136 	case EM_SPARCV9:
137 		reg = _get_dwarf_regnum(sparc_regstr_tbl, name);
138 		break;
139 	case EM_XTENSA:
140 		reg = _get_dwarf_regnum(xtensa_regstr_tbl, name);
141 		break;
142 	case EM_MIPS:
143 		reg = _get_dwarf_regnum(mips_regstr_tbl, name);
144 		break;
145 	case EM_LOONGARCH:
146 		reg = _get_dwarf_regnum(loongarch_regstr_tbl, name);
147 		break;
148 	default:
149 		pr_err("ELF MACHINE %x is not supported.\n", machine);
150 	}
151 	free(regname);
152 	return reg;
153 
154 	#undef _get_dwarf_regnum
155 }
156 
157 static int get_libdw_frame_nregs(unsigned int machine, unsigned int flags __maybe_unused)
158 {
159 	switch (machine) {
160 	case EM_X86_64:
161 		return 17;
162 	case EM_386:
163 		return 9;
164 	case EM_ARM:
165 		return 16;
166 	case EM_AARCH64:
167 		return 97;
168 	case EM_CSKY:
169 		return 38;
170 	case EM_S390:
171 		return 32;
172 	case EM_PPC:
173 	case EM_PPC64:
174 		return 145;
175 	case EM_RISCV:
176 		return 66;
177 	case EM_SPARC:
178 	case EM_SPARCV9:
179 		return 103;
180 	case EM_LOONGARCH:
181 		return 74;
182 	case EM_MIPS:
183 		return 71;
184 	default:
185 		return 0;
186 	}
187 }
188 
189 int get_dwarf_regnum_for_perf_regnum(int perf_regnum, unsigned int machine,
190 				     unsigned int flags, bool only_libdw_supported)
191 {
192 	int reg;
193 
194 	switch (machine) {
195 	case EM_X86_64:
196 		reg = __get_dwarf_regnum_for_perf_regnum_x86_64(perf_regnum);
197 		break;
198 	case EM_386:
199 		reg = __get_dwarf_regnum_for_perf_regnum_i386(perf_regnum);
200 		break;
201 	case EM_ARM:
202 		reg = __get_dwarf_regnum_for_perf_regnum_arm(perf_regnum);
203 		break;
204 	case EM_AARCH64:
205 		reg = __get_dwarf_regnum_for_perf_regnum_arm64(perf_regnum);
206 		break;
207 	case EM_CSKY:
208 		reg = __get_dwarf_regnum_for_perf_regnum_csky(perf_regnum, flags);
209 		break;
210 	case EM_PPC:
211 	case EM_PPC64:
212 		reg = __get_dwarf_regnum_for_perf_regnum_powerpc(perf_regnum);
213 		break;
214 	case EM_RISCV:
215 		reg = __get_dwarf_regnum_for_perf_regnum_riscv(perf_regnum);
216 		break;
217 	case EM_S390:
218 		reg = __get_dwarf_regnum_for_perf_regnum_s390(perf_regnum);
219 		break;
220 	case EM_LOONGARCH:
221 		reg = __get_dwarf_regnum_for_perf_regnum_loongarch(perf_regnum);
222 		break;
223 	case EM_MIPS:
224 		reg = __get_dwarf_regnum_for_perf_regnum_mips(perf_regnum);
225 		break;
226 	default:
227 		pr_err("ELF MACHINE %x is not supported.\n", machine);
228 		return -ENOENT;
229 	}
230 	if (reg >= 0 && only_libdw_supported) {
231 		int nregs = get_libdw_frame_nregs(machine, flags);
232 
233 		if (reg >= nregs)
234 			reg = -ENOENT;
235 	}
236 	return reg;
237 }
238