1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright (C) 2017 Josh Poimboeuf <jpoimboe@redhat.com>
13 int create_orc(struct objtool_file *file)
15 struct instruction *insn;
17 for_each_insn(file, insn) {
18 struct orc_entry *orc = &insn->orc;
19 struct cfi_reg *cfa = &insn->state.cfa;
20 struct cfi_reg *bp = &insn->state.regs[CFI_BP];
22 orc->end = insn->state.end;
24 if (cfa->base == CFI_UNDEFINED) {
25 orc->sp_reg = ORC_REG_UNDEFINED;
31 orc->sp_reg = ORC_REG_SP;
34 orc->sp_reg = ORC_REG_SP_INDIRECT;
37 orc->sp_reg = ORC_REG_BP;
40 orc->sp_reg = ORC_REG_BP_INDIRECT;
43 orc->sp_reg = ORC_REG_R10;
46 orc->sp_reg = ORC_REG_R13;
49 orc->sp_reg = ORC_REG_DI;
52 orc->sp_reg = ORC_REG_DX;
55 WARN_FUNC("unknown CFA base reg %d",
56 insn->sec, insn->offset, cfa->base);
62 orc->bp_reg = ORC_REG_UNDEFINED;
65 orc->bp_reg = ORC_REG_PREV_SP;
68 orc->bp_reg = ORC_REG_BP;
71 WARN_FUNC("unknown BP base reg %d",
72 insn->sec, insn->offset, bp->base);
76 orc->sp_offset = cfa->offset;
77 orc->bp_offset = bp->offset;
78 orc->type = insn->state.type;
84 static int create_orc_entry(struct elf *elf, struct section *u_sec, struct section *ip_relasec,
85 unsigned int idx, struct section *insn_sec,
86 unsigned long insn_off, struct orc_entry *o)
88 struct orc_entry *orc;
92 WARN("missing symbol for section %s", insn_sec->name);
96 /* populate ORC data */
97 orc = (struct orc_entry *)u_sec->data->d_buf + idx;
98 memcpy(orc, o, sizeof(*orc));
100 /* populate rela for ip */
101 rela = malloc(sizeof(*rela));
106 memset(rela, 0, sizeof(*rela));
108 rela->sym = insn_sec->sym;
109 rela->addend = insn_off;
110 rela->type = R_X86_64_PC32;
111 rela->offset = idx * sizeof(int);
112 rela->sec = ip_relasec;
114 list_add_tail(&rela->list, &ip_relasec->rela_list);
115 hash_add(elf->rela_hash, &rela->hash, rela_hash(rela));
120 int create_orc_sections(struct objtool_file *file)
122 struct instruction *insn, *prev_insn;
123 struct section *sec, *u_sec, *ip_relasec;
126 struct orc_entry empty = {
127 .sp_reg = ORC_REG_UNDEFINED,
128 .bp_reg = ORC_REG_UNDEFINED,
129 .type = ORC_TYPE_CALL,
132 sec = find_section_by_name(file->elf, ".orc_unwind");
134 WARN("file already has .orc_unwind section, skipping");
138 /* count the number of needed orcs */
140 for_each_sec(file, sec) {
145 sec_for_each_insn(file, sec, insn) {
147 memcmp(&insn->orc, &prev_insn->orc,
148 sizeof(struct orc_entry))) {
154 /* section terminator */
162 /* create .orc_unwind_ip and .rela.orc_unwind_ip sections */
163 sec = elf_create_section(file->elf, ".orc_unwind_ip", sizeof(int), idx);
167 ip_relasec = elf_create_rela_section(file->elf, sec);
171 /* create .orc_unwind section */
172 u_sec = elf_create_section(file->elf, ".orc_unwind",
173 sizeof(struct orc_entry), idx);
175 /* populate sections */
177 for_each_sec(file, sec) {
182 sec_for_each_insn(file, sec, insn) {
183 if (!prev_insn || memcmp(&insn->orc, &prev_insn->orc,
184 sizeof(struct orc_entry))) {
186 if (create_orc_entry(file->elf, u_sec, ip_relasec, idx,
187 insn->sec, insn->offset,
196 /* section terminator */
198 if (create_orc_entry(file->elf, u_sec, ip_relasec, idx,
200 prev_insn->offset + prev_insn->len,
208 if (elf_rebuild_rela_section(ip_relasec))