diff options
| -rw-r--r-- | tools/objtool/disas.c | 70 |
1 files changed, 66 insertions, 4 deletions
diff --git a/tools/objtool/disas.c b/tools/objtool/disas.c index 326e16c9f30a..f8917c8405d3 100644 --- a/tools/objtool/disas.c +++ b/tools/objtool/disas.c @@ -24,6 +24,7 @@ struct disas_context { struct objtool_file *file; struct instruction *insn; + bool alt_applied; char result[DISAS_RESULT_SIZE]; disassembler_ftype disassembler; struct disassemble_info info; @@ -160,6 +161,43 @@ static void disas_print_addr_sym(struct section *sec, struct symbol *sym, } } +static bool disas_print_addr_alt(bfd_vma addr, struct disassemble_info *dinfo) +{ + struct disas_context *dctx = dinfo->application_data; + struct instruction *orig_first_insn; + struct alt_group *alt_group; + unsigned long offset; + struct symbol *sym; + + /* + * Check if we are processing an alternative at the original + * instruction address (i.e. if alt_applied is true) and if + * we are referencing an address inside the alternative. + * + * For example, this happens if there is a branch inside an + * alternative. In that case, the address should be updated + * to a reference inside the original instruction flow. + */ + if (!dctx->alt_applied) + return false; + + alt_group = dctx->insn->alt_group; + if (!alt_group || !alt_group->orig_group || + addr < alt_group->first_insn->offset || + addr > alt_group->last_insn->offset) + return false; + + orig_first_insn = alt_group->orig_group->first_insn; + offset = addr - alt_group->first_insn->offset; + + addr = orig_first_insn->offset + offset; + sym = orig_first_insn->sym; + + disas_print_addr_sym(orig_first_insn->sec, sym, addr, dinfo); + + return true; +} + static void disas_print_addr_noreloc(bfd_vma addr, struct disassemble_info *dinfo) { @@ -167,6 +205,9 @@ static void disas_print_addr_noreloc(bfd_vma addr, struct instruction *insn = dctx->insn; struct symbol *sym = NULL; + if (disas_print_addr_alt(addr, dinfo)) + return; + if (insn->sym && addr >= insn->sym->offset && addr < insn->sym->offset + insn->sym->len) { sym = insn->sym; @@ -232,8 +273,9 @@ static void disas_print_address(bfd_vma addr, struct disassemble_info *dinfo) */ jump_dest = insn->jump_dest; if (jump_dest && jump_dest->sym && jump_dest->offset == addr) { - disas_print_addr_sym(jump_dest->sec, jump_dest->sym, - addr, dinfo); + if (!disas_print_addr_alt(addr, dinfo)) + disas_print_addr_sym(jump_dest->sec, jump_dest->sym, + addr, dinfo); return; } @@ -490,13 +532,22 @@ void disas_print_insn(FILE *stream, struct disas_context *dctx, /* * Disassemble a single instruction. Return the size of the instruction. + * + * If alt_applied is true then insn should be an instruction from of an + * alternative (i.e. insn->alt_group != NULL), and it is disassembled + * at the location of the original code it is replacing. When the + * instruction references any address inside the alternative then + * these references will be re-adjusted to replace the original code. */ -size_t disas_insn(struct disas_context *dctx, struct instruction *insn) +static size_t disas_insn_common(struct disas_context *dctx, + struct instruction *insn, + bool alt_applied) { disassembler_ftype disasm = dctx->disassembler; struct disassemble_info *dinfo = &dctx->info; dctx->insn = insn; + dctx->alt_applied = alt_applied; dctx->result[0] = '\0'; if (insn->type == INSN_NOP) { @@ -515,6 +566,17 @@ size_t disas_insn(struct disas_context *dctx, struct instruction *insn) return disasm(insn->offset, &dctx->info); } +size_t disas_insn(struct disas_context *dctx, struct instruction *insn) +{ + return disas_insn_common(dctx, insn, false); +} + +static size_t disas_insn_alt(struct disas_context *dctx, + struct instruction *insn) +{ + return disas_insn_common(dctx, insn, true); +} + static struct instruction *next_insn_same_alt(struct objtool_file *file, struct alt_group *alt_grp, struct instruction *insn) @@ -706,7 +768,7 @@ static int disas_alt_group(struct disas_context *dctx, struct disas_alt *dalt) alt_for_each_insn(file, DALT_GROUP(dalt), insn) { - disas_insn(dctx, insn); + disas_insn_alt(dctx, insn); str = strdup(disas_result(dctx)); if (!str) return -1; |