diff options
Diffstat (limited to 'bfd/dwarf2.c')
| -rw-r--r-- | bfd/dwarf2.c | 140 |
1 files changed, 110 insertions, 30 deletions
diff --git a/bfd/dwarf2.c b/bfd/dwarf2.c index 1ea7cff..3af1645 100644 --- a/bfd/dwarf2.c +++ b/bfd/dwarf2.c @@ -631,6 +631,7 @@ struct line_info { char* filename; unsigned int line; unsigned int column; + int end_sequence; /* end of (sequential) code sequence */ }; struct fileinfo { @@ -653,12 +654,13 @@ struct line_info_table { }; static void -add_line_info (table, address, filename, line, column) +add_line_info (table, address, filename, line, column, end_sequence) struct line_info_table* table; bfd_vma address; char* filename; unsigned int line; unsigned int column; + int end_sequence; { struct line_info* info = (struct line_info*) bfd_alloc (table->abfd, sizeof (struct line_info)); @@ -670,6 +672,7 @@ add_line_info (table, address, filename, line, column) info->filename = filename; info->line = line; info->column = column; + info->end_sequence = end_sequence; } static char* @@ -677,7 +680,16 @@ concat_filename (table, file) struct line_info_table* table; unsigned int file; { - char* filename = table->files[file - 1].name; + char* filename; + + if (file - 1 >= table->num_files) + { + (*_bfd_error_handler) (_("Dwarf Error: mangled line number " + "section (bad file number).")); + return "<unknown>"; + } + + filename = table->files[file - 1].name; if (*filename == '/') return filename; @@ -708,6 +720,12 @@ decode_line_info (unit) unsigned int i, bytes_read; char *cur_file, *cur_dir; unsigned char op_code, extended_op, adj_opcode; +#if 0 + /* This optimization unfortunately does not work well on programs + that have multiple sections containing text (such as Linux which + uses .text, and .text.init, for example. */ + bfd_vma hi_pc = 0, lo_pc = ~ (bfd_vma) 0; +#endif if (! dwarf_line_buffer) { @@ -747,6 +765,9 @@ decode_line_info (unit) table->num_dirs = 0; table->dirs = NULL; + table->files = NULL; + table->last_line = NULL; + line_ptr = dwarf_line_buffer + unit->line_offset; /* read in the prologue */ @@ -831,6 +852,7 @@ decode_line_info (unit) int is_stmt = lh.default_is_stmt; int basic_block = 0; int end_sequence = 0; + boolean first_time = true; /* Decode the table. */ while (! end_sequence) @@ -847,7 +869,7 @@ decode_line_info (unit) { case DW_LNE_end_sequence: end_sequence = 1; - add_line_info (table, address, filename, line, column); + add_line_info (table, address, filename, line, column, end_sequence); break; case DW_LNE_set_address: address = read_address (unit, line_ptr); @@ -884,7 +906,7 @@ decode_line_info (unit) } break; case DW_LNS_copy: - add_line_info (table, address, filename, line, column); + add_line_info (table, address, filename, line, column, 0); basic_block = 0; break; case DW_LNS_advance_pc: @@ -918,7 +940,8 @@ decode_line_info (unit) basic_block = 1; break; case DW_LNS_const_add_pc: - address += (255 - lh.opcode_base) / lh.line_range; + address += lh.minimum_instruction_length + * ((255 - lh.opcode_base) / lh.line_range); break; case DW_LNS_fixed_advance_pc: address += read_2_bytes (abfd, line_ptr); @@ -930,11 +953,27 @@ decode_line_info (unit) * lh.minimum_instruction_length; line += lh.line_base + (adj_opcode % lh.line_range); /* append row to matrix using current values */ - add_line_info (table, address, filename, line, column); + add_line_info (table, address, filename, line, column, 0); basic_block = 1; } +#if 0 + if (unit->high == 0) + { + if (address > hi_pc) + hi_pc = address; + if (address < lo_pc) + lo_pc = address; + } +#endif } } +#if 0 + if (unit->high == 0 && hi_pc != 0) + { + unit->high = hi_pc; + unit->low = lo_pc; + } +#endif return table; } @@ -954,21 +993,25 @@ lookup_address_in_line_info_table (table, const char **filename_ptr; unsigned int *linenumber_ptr; { + struct line_info* next_line = table->last_line; struct line_info* each_line; - struct line_info* next_line; - for (next_line = 0, each_line = table->last_line; - each_line; - next_line = each_line, each_line = each_line->prev_line) + if (!next_line) + return false; + + each_line = next_line->prev_line; + + while (each_line && next_line) { - if (addr >= each_line->address - && (next_line == 0 - || addr < next_line->address)) + if (!each_line->end_sequence + && addr >= each_line->address && addr < next_line->address) { *filename_ptr = each_line->filename; *linenumber_ptr = each_line->line; return true; } + next_line = each_line; + each_line = each_line->prev_line; } return false; @@ -1363,6 +1406,8 @@ _bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset, struct comp_unit* each; + boolean found; + *filename_ptr = NULL; *functionname_ptr = NULL; *linenumber_ptr = 0; @@ -1404,14 +1449,20 @@ _bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset, stash->info_ptr_end = stash->info_ptr + size; - /* FIXME: There is a problem with the contents of the .debug_info section. - The 'low' and 'high' addresses of the comp_units are computed by relocs - against symbols in the .text segment. We need these addresses in - order to determine the nearest line number, and so we have to resolve - the relocs. There is a similar problem when the .debug_line section is - processed as well. + /* FIXME: There is a problem with the contents of the + .debug_info section. The 'low' and 'high' addresses of the + comp_units are computed by relocs against symbols in the + .text segment. We need these addresses in order to determine + the nearest line number, and so we have to resolve the + relocs. There is a similar problem when the .debug_line + section is processed as well (e.g., there may be relocs + against the operand of the DW_LNE_set_address operator). - Unfortunately getting hold of the reloc information is hard... */ + Unfortunately getting hold of the reloc information is hard... + + For now, this means that disassembling object files (as + opposed to fully executables) does not always work as well as + we would like. */ } /* A null info_ptr indicates that there is no dwarf2 info @@ -1424,11 +1475,23 @@ _bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset, for (each = stash->all_comp_units; each; each = each->next_unit) { - if (comp_unit_contains_address (each, addr)) - return comp_unit_find_nearest_line (each, addr, - filename_ptr, - functionname_ptr, - linenumber_ptr); + if (each->high > 0) + { + if (comp_unit_contains_address (each, addr)) + return comp_unit_find_nearest_line (each, addr, + filename_ptr, + functionname_ptr, + linenumber_ptr); + } + else + { + found = comp_unit_find_nearest_line (each, addr, + filename_ptr, + functionname_ptr, + linenumber_ptr); + if (found) + return true; + } } /* Read each remaining comp. units checking each as they are read. */ @@ -1451,11 +1514,28 @@ _bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset, each->next_unit = stash->all_comp_units; stash->all_comp_units = each; - if (comp_unit_contains_address (each, addr)) - return comp_unit_find_nearest_line (each, addr, - filename_ptr, - functionname_ptr, - linenumber_ptr); + /* DW_AT_low_pc and DW_AT_high_pc are optional for + compilation units. If we don't have them (i.e., + unit->high == 0), we need to consult the line info + table to see if a compilation unit contains the given + address. */ + if (each->high > 0) + { + if (comp_unit_contains_address (each, addr)) + return comp_unit_find_nearest_line (each, addr, + filename_ptr, + functionname_ptr, + linenumber_ptr); + } + else + { + found = comp_unit_find_nearest_line (each, addr, + filename_ptr, + functionname_ptr, + linenumber_ptr); + if (found) + return true; + } } } } |