xref: /linux/tools/objtool/arch/loongarch/orc.c (revision 7fc2cd2e4b398c57c9cf961cfea05eadbf34c05c)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 #include <linux/objtool_types.h>
3 #include <asm/orc_types.h>
4 
5 #include <objtool/check.h>
6 #include <objtool/orc.h>
7 #include <objtool/warn.h>
8 
9 int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi, struct instruction *insn)
10 {
11 	struct cfi_reg *fp = &cfi->regs[CFI_FP];
12 	struct cfi_reg *ra = &cfi->regs[CFI_RA];
13 
14 	memset(orc, 0, sizeof(*orc));
15 
16 	if (!cfi) {
17 		/*
18 		 * This is usually either unreachable nops/traps (which don't
19 		 * trigger unreachable instruction warnings), or
20 		 * STACK_FRAME_NON_STANDARD functions.
21 		 */
22 		orc->type = ORC_TYPE_UNDEFINED;
23 		return 0;
24 	}
25 
26 	switch (cfi->type) {
27 	case UNWIND_HINT_TYPE_UNDEFINED:
28 		orc->type = ORC_TYPE_UNDEFINED;
29 		return 0;
30 	case UNWIND_HINT_TYPE_END_OF_STACK:
31 		orc->type = ORC_TYPE_END_OF_STACK;
32 		return 0;
33 	case UNWIND_HINT_TYPE_CALL:
34 		orc->type = ORC_TYPE_CALL;
35 		break;
36 	case UNWIND_HINT_TYPE_REGS:
37 		orc->type = ORC_TYPE_REGS;
38 		break;
39 	case UNWIND_HINT_TYPE_REGS_PARTIAL:
40 		orc->type = ORC_TYPE_REGS_PARTIAL;
41 		break;
42 	default:
43 		ERROR_INSN(insn, "unknown unwind hint type %d", cfi->type);
44 		return -1;
45 	}
46 
47 	orc->signal = cfi->signal;
48 
49 	switch (cfi->cfa.base) {
50 	case CFI_SP:
51 		orc->sp_reg = ORC_REG_SP;
52 		break;
53 	case CFI_FP:
54 		orc->sp_reg = ORC_REG_FP;
55 		break;
56 	default:
57 		ERROR_INSN(insn, "unknown CFA base reg %d", cfi->cfa.base);
58 		return -1;
59 	}
60 
61 	switch (fp->base) {
62 	case CFI_UNDEFINED:
63 		orc->fp_reg = ORC_REG_UNDEFINED;
64 		orc->fp_offset = 0;
65 		break;
66 	case CFI_CFA:
67 		orc->fp_reg = ORC_REG_PREV_SP;
68 		orc->fp_offset = fp->offset;
69 		break;
70 	case CFI_FP:
71 		orc->fp_reg = ORC_REG_FP;
72 		break;
73 	default:
74 		ERROR_INSN(insn, "unknown FP base reg %d", fp->base);
75 		return -1;
76 	}
77 
78 	switch (ra->base) {
79 	case CFI_UNDEFINED:
80 		orc->ra_reg = ORC_REG_UNDEFINED;
81 		orc->ra_offset = 0;
82 		break;
83 	case CFI_CFA:
84 		orc->ra_reg = ORC_REG_PREV_SP;
85 		orc->ra_offset = ra->offset;
86 		break;
87 	case CFI_FP:
88 		orc->ra_reg = ORC_REG_FP;
89 		break;
90 	default:
91 		ERROR_INSN(insn, "unknown RA base reg %d", ra->base);
92 		return -1;
93 	}
94 
95 	orc->sp_offset = cfi->cfa.offset;
96 
97 	return 0;
98 }
99 
100 int write_orc_entry(struct elf *elf, struct section *orc_sec,
101 		    struct section *ip_sec, unsigned int idx,
102 		    struct section *insn_sec, unsigned long insn_off,
103 		    struct orc_entry *o)
104 {
105 	struct orc_entry *orc;
106 
107 	/* populate ORC data */
108 	orc = (struct orc_entry *)orc_sec->data->d_buf + idx;
109 	memcpy(orc, o, sizeof(*orc));
110 
111 	/* populate reloc for ip */
112 	if (!elf_init_reloc_text_sym(elf, ip_sec, idx * sizeof(int), idx,
113 				     insn_sec, insn_off))
114 		return -1;
115 
116 	return 0;
117 }
118 
119 static const char *reg_name(unsigned int reg)
120 {
121 	switch (reg) {
122 	case ORC_REG_SP:
123 		return "sp";
124 	case ORC_REG_FP:
125 		return "fp";
126 	case ORC_REG_PREV_SP:
127 		return "prevsp";
128 	default:
129 		return "?";
130 	}
131 }
132 
133 static const char *orc_type_name(unsigned int type)
134 {
135 	switch (type) {
136 	case UNWIND_HINT_TYPE_CALL:
137 		return "call";
138 	case UNWIND_HINT_TYPE_REGS:
139 		return "regs";
140 	case UNWIND_HINT_TYPE_REGS_PARTIAL:
141 		return "regs (partial)";
142 	default:
143 		return "?";
144 	}
145 }
146 
147 static void print_reg(unsigned int reg, int offset)
148 {
149 	if (reg == ORC_REG_UNDEFINED)
150 		printf(" (und) ");
151 	else
152 		printf("%s + %3d", reg_name(reg), offset);
153 
154 }
155 
156 void orc_print_dump(struct elf *dummy_elf, struct orc_entry *orc, int i)
157 {
158 	printf("type:%s", orc_type_name(orc[i].type));
159 
160 	printf(" sp:");
161 	print_reg(orc[i].sp_reg, orc[i].sp_offset);
162 
163 	printf(" fp:");
164 	print_reg(orc[i].fp_reg, orc[i].fp_offset);
165 
166 	printf(" ra:");
167 	print_reg(orc[i].ra_reg, orc[i].ra_offset);
168 
169 	printf(" signal:%d\n", orc[i].signal);
170 }
171