From a092b084322453a828644233b611471d04061a37 Mon Sep 17 00:00:00 2001 From: Nick Clifton Date: Sat, 2 Sep 2000 20:21:40 +0000 Subject: [PATCH] Find all sections containing debug information and include them in the stash. --- bfd/ChangeLog | 7 + bfd/dwarf2.c | 405 +++++++++++++++++++++++++++----------------------- 2 files changed, 224 insertions(+), 188 deletions(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 9255101f86..9e0623c05e 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,10 @@ +2000-09-02 Nick Clifton + + * dwarf2.c (find_debug_info): New function: Locate a section + containing dwarf2 debug information. + (bfd_dwarf2_find_nearest_line): Find all sections containing + debug information and include them in the stash. + 2000-09-01 Niibe Yutaka , Kaz Kojima , Alexandre Oliva * elf32-sh.c (R_SH_GOT32, R_SH_PLT32, R_SH_COPY, R_SH_GLOB_DAT, diff --git a/bfd/dwarf2.c b/bfd/dwarf2.c index 1c02912d21..7c8ddfdb0d 100644 --- a/bfd/dwarf2.c +++ b/bfd/dwarf2.c @@ -36,36 +36,38 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "elf/dwarf2.h" /* The data in the .debug_line statement prologue looks like this. */ + struct line_head - { - unsigned int total_length; - unsigned short version; - unsigned int prologue_length; - unsigned char minimum_instruction_length; - unsigned char default_is_stmt; - int line_base; - unsigned char line_range; - unsigned char opcode_base; - unsigned char *standard_opcode_lengths; - }; +{ + unsigned int total_length; + unsigned short version; + unsigned int prologue_length; + unsigned char minimum_instruction_length; + unsigned char default_is_stmt; + int line_base; + unsigned char line_range; + unsigned char opcode_base; + unsigned char *standard_opcode_lengths; +}; + +/* Attributes have a name and a value. */ -/* Attributes have a name and a value */ struct attribute +{ + enum dwarf_attribute name; + enum dwarf_form form; + union { - enum dwarf_attribute name; - enum dwarf_form form; - union - { - char *str; - struct dwarf_block *blk; - unsigned int unsnd; - int snd; - bfd_vma addr; - } - u; - }; + char *str; + struct dwarf_block *blk; + unsigned int unsnd; + int snd; + bfd_vma addr; + } + u; +}; -/* Get at parts of an attribute structure */ +/* Get at parts of an attribute structure. */ #define DW_STRING(attr) ((attr)->u.str) #define DW_UNSND(attr) ((attr)->u.unsnd) @@ -75,29 +77,28 @@ struct attribute /* Blocks are a bunch of untyped bytes. */ struct dwarf_block - { - unsigned int size; - char *data; - }; +{ + unsigned int size; + char *data; +}; - -struct dwarf2_debug { - - /* A list of all previously read comp_units. */ +struct dwarf2_debug +{ + /* A list of all previously read comp_units. */ struct comp_unit* all_comp_units; /* The next unread compilation unit within the .debug_info section. Zero indicates that the .debug_info section has not been loaded - into a buffer yet.*/ + into a buffer yet. */ char* info_ptr; - /* Pointer to the end of the .debug_info section memory buffer. */ + /* Pointer to the end of the .debug_info section memory buffer. */ char* info_ptr_end; - /* Pointer to the .debug_abbrev section loaded into memory. */ + /* Pointer to the .debug_abbrev section loaded into memory. */ char* dwarf_abbrev_buffer; - /* Length of the loaded .debug_abbrev section. */ + /* Length of the loaded .debug_abbrev section. */ unsigned long dwarf_abbrev_size; /* Buffer for decode_line_info. */ @@ -107,69 +108,67 @@ struct dwarf2_debug { unsigned long dwarf_line_size; }; -struct arange { +struct arange +{ struct arange *next; bfd_vma low; bfd_vma high; }; - /* A minimal decoding of DWARF2 compilation units. We only decode - what's needed to get to the line number information. */ + what's needed to get to the line number information. */ -struct comp_unit { - - /* Chain the previously read compilation units. */ +struct comp_unit +{ + /* Chain the previously read compilation units. */ struct comp_unit* next_unit; - /* Keep the bdf convenient (for memory allocation). */ + /* Keep the bdf convenient (for memory allocation). */ bfd* abfd; /* The lowest and higest addresses contained in this compilation - unit as specified in the compilation unit header. */ + unit as specified in the compilation unit header. */ struct arange arange; - /* The DW_AT_name attribute (for error messages). */ + /* The DW_AT_name attribute (for error messages). */ char* name; - /* The abbrev hash table. */ + /* The abbrev hash table. */ struct abbrev_info** abbrevs; - /* Note that an error was found by comp_unit_find_nearest_line. */ + /* Note that an error was found by comp_unit_find_nearest_line. */ int error; - /* The DW_AT_comp_dir attribute */ + /* The DW_AT_comp_dir attribute. */ char* comp_dir; - /* True if there is a line number table associated with this comp. unit. */ + /* True if there is a line number table associated with this comp. unit. */ int stmtlist; - /* The offset into .debug_line of the line number table. */ + /* The offset into .debug_line of the line number table. */ unsigned long line_offset; - /* Pointer to the first child die for the comp unit. */ + /* Pointer to the first child die for the comp unit. */ char *first_child_die_ptr; - /* The end of the comp unit. */ + /* The end of the comp unit. */ char *end_ptr; - /* The decoded line number, NULL if not yet decoded. */ + /* The decoded line number, NULL if not yet decoded. */ struct line_info_table* line_table; - /* A list of the functions found in this comp. unit. */ + /* A list of the functions found in this comp. unit. */ struct funcinfo* function_table; - /* Address size for this unit - from unit header */ + /* Address size for this unit - from unit header. */ unsigned char addr_size; }; - - /* VERBATIM The following function up to the END VERBATIM mark are - copied directly from dwarf2read.c. */ + copied directly from dwarf2read.c. */ -/* read dwarf information from a buffer */ +/* Read dwarf information from a buffer. */ static unsigned int read_1_byte (abfd, buf) @@ -195,9 +194,7 @@ read_2_bytes (abfd, buf) return bfd_get_16 (abfd, (bfd_byte *) buf); } -#if 0 - -/* This is not used. */ +#if 0 /* This is not used. */ static int read_2_signed_bytes (abfd, buf) @@ -217,9 +214,7 @@ read_4_bytes (abfd, buf) return bfd_get_32 (abfd, (bfd_byte *) buf); } -#if 0 - -/* This is not used. */ +#if 0 /* This is not used. */ static int read_4_signed_bytes (abfd, buf) @@ -265,6 +260,7 @@ read_string (abfd, buf, bytes_read_ptr) *bytes_read_ptr = 1; return NULL; } + *bytes_read_ptr = strlen (buf) + 1; return buf; } @@ -352,26 +348,22 @@ read_address (unit, buf) } } - - - - /* This data structure holds the information of an abbrev. */ struct abbrev_info - { - unsigned int number; /* number identifying abbrev */ - enum dwarf_tag tag; /* dwarf tag */ - int has_children; /* boolean */ - unsigned int num_attrs; /* number of attributes */ - struct attr_abbrev *attrs; /* an array of attribute descriptions */ - struct abbrev_info *next; /* next in chain */ - }; +{ + unsigned int number; /* Number identifying abbrev. */ + enum dwarf_tag tag; /* DWARF tag. */ + int has_children; /* Boolean. */ + unsigned int num_attrs; /* Number of attributes. */ + struct attr_abbrev *attrs; /* An array of attribute descriptions. */ + struct abbrev_info *next; /* Next in chain. */ +}; struct attr_abbrev - { - enum dwarf_attribute name; - enum dwarf_form form; - }; +{ + enum dwarf_attribute name; + enum dwarf_form form; +}; #ifndef ABBREV_HASH_SIZE #define ABBREV_HASH_SIZE 121 @@ -400,6 +392,7 @@ lookup_abbrev (number,abbrevs) else abbrev = abbrev->next; } + return NULL; } @@ -459,23 +452,24 @@ read_abbrevs (abfd, offset) abbrev_number = read_unsigned_leb128 (abfd, abbrev_ptr, &bytes_read); abbrev_ptr += bytes_read; - /* loop until we reach an abbrev number of 0 */ + /* Loop until we reach an abbrev number of 0. */ while (abbrev_number) { cur_abbrev = (struct abbrev_info*)bfd_zalloc (abfd, sizeof (struct abbrev_info)); - /* read in abbrev header */ + /* Read in abbrev header. */ cur_abbrev->number = abbrev_number; cur_abbrev->tag = read_unsigned_leb128 (abfd, abbrev_ptr, &bytes_read); abbrev_ptr += bytes_read; cur_abbrev->has_children = read_1_byte (abfd, abbrev_ptr); abbrev_ptr += 1; - /* now read in declarations */ + /* Now read in declarations. */ abbrev_name = read_unsigned_leb128 (abfd, abbrev_ptr, &bytes_read); abbrev_ptr += bytes_read; abbrev_form = read_unsigned_leb128 (abfd, abbrev_ptr, &bytes_read); abbrev_ptr += bytes_read; + while (abbrev_name) { if ((cur_abbrev->num_attrs % ATTR_ALLOC_CHUNK) == 0) @@ -487,6 +481,7 @@ read_abbrevs (abfd, offset) if (! cur_abbrev->attrs) return 0; } + cur_abbrev->attrs[cur_abbrev->num_attrs].name = abbrev_name; cur_abbrev->attrs[cur_abbrev->num_attrs++].form = abbrev_form; abbrev_name = read_unsigned_leb128 (abfd, abbrev_ptr, &bytes_read); @@ -533,6 +528,7 @@ read_attribute (attr, abbrev, unit, info_ptr) attr->name = abbrev->name; attr->form = abbrev->form; + switch (abbrev->form) { case DW_FORM_addr: @@ -634,35 +630,34 @@ read_attribute (attr, abbrev, unit, info_ptr) return info_ptr; } - -/* Source line information table routines. */ +/* Source line information table routines. */ #define FILE_ALLOC_CHUNK 5 #define DIR_ALLOC_CHUNK 5 -struct line_info { +struct line_info +{ struct line_info* prev_line; - bfd_vma address; char* filename; unsigned int line; unsigned int column; - int end_sequence; /* end of (sequential) code sequence */ + int end_sequence; /* End of (sequential) code sequence. */ }; -struct fileinfo { +struct fileinfo +{ char *name; unsigned int dir; unsigned int time; unsigned int size; }; -struct line_info_table { +struct line_info_table +{ bfd* abfd; - unsigned int num_files; unsigned int num_dirs; - char* comp_dir; char** dirs; struct fileinfo* files; @@ -691,7 +686,7 @@ add_line_info (table, address, filename, line, column, end_sequence) info->end_sequence = end_sequence; } -static char* +static char * concat_filename (table, file) struct line_info_table* table; unsigned int file; @@ -726,8 +721,9 @@ arange_add (unit, low_pc, high_pc) { struct arange *arange; - /* first see if we can cheaply extend an existing range: */ + /* First see if we can cheaply extend an existing range. */ arange = &unit->arange; + do { if (low_pc == arange->high) @@ -746,14 +742,14 @@ arange_add (unit, low_pc, high_pc) if (unit->arange.high == 0) { - /* this is the first address range: store it in unit->arange: */ + /* This is the first address range: store it in unit->arange. */ unit->arange.next = 0; unit->arange.low = low_pc; unit->arange.high = high_pc; return; } - /* need to allocate a new arange and insert it into the arange list: */ + /* Need to allocate a new arange and insert it into the arange list. */ arange = bfd_zalloc (unit->abfd, sizeof (*arange)); arange->low = low_pc; arange->high = high_pc; @@ -762,18 +758,15 @@ arange_add (unit, low_pc, high_pc) unit->arange.next = arange; } -/* Decode the line number information for UNIT. */ +/* Decode the line number information for UNIT. */ static struct line_info_table* decode_line_info (unit) struct comp_unit *unit; { bfd *abfd = unit->abfd; - struct dwarf2_debug *stash; - struct line_info_table* table; - char *line_ptr; char *line_end; struct line_head lh; @@ -806,7 +799,7 @@ decode_line_info (unit) return 0; /* FIXME: We ought to apply the relocs against this section before - we process it.... */ + we process it... */ } /* Since we are using un-relocated data, it is possible to get a bad value @@ -836,7 +829,7 @@ decode_line_info (unit) line_ptr = stash->dwarf_line_buffer + unit->line_offset; - /* read in the prologue */ + /* Read in the prologue. */ lh.total_length = read_4_bytes (abfd, line_ptr); line_ptr += 4; line_end = line_ptr + lh.total_length; @@ -858,16 +851,18 @@ decode_line_info (unit) bfd_alloc (abfd, lh.opcode_base * sizeof (unsigned char)); lh.standard_opcode_lengths[0] = 1; + for (i = 1; i < lh.opcode_base; ++i) { lh.standard_opcode_lengths[i] = read_1_byte (abfd, line_ptr); line_ptr += 1; } - /* Read directory table */ + /* Read directory table. */ while ((cur_dir = read_string (abfd, line_ptr, &bytes_read)) != NULL) { line_ptr += bytes_read; + if ((table->num_dirs % DIR_ALLOC_CHUNK) == 0) { table->dirs = (char **) @@ -876,14 +871,17 @@ decode_line_info (unit) if (! table->dirs) return 0; } + table->dirs[table->num_dirs++] = cur_dir; } + line_ptr += bytes_read; - /* Read file name table */ + /* Read file name table. */ while ((cur_file = read_string (abfd, line_ptr, &bytes_read)) != NULL) { line_ptr += bytes_read; + if ((table->num_files % FILE_ALLOC_CHUNK) == 0) { table->files = (struct fileinfo *) @@ -893,6 +891,7 @@ decode_line_info (unit) if (! table->files) return 0; } + table->files[table->num_files].name = cur_file; table->files[table->num_files].dir = read_unsigned_leb128 (abfd, line_ptr, &bytes_read); @@ -905,12 +904,13 @@ decode_line_info (unit) line_ptr += bytes_read; table->num_files++; } + line_ptr += bytes_read; /* Read the statement sequences until there's nothing left. */ while (line_ptr < line_end) { - /* state machine registers */ + /* State machine registers. */ bfd_vma address = 0; char* filename = concat_filename (table, 1); unsigned int line = 1; @@ -920,15 +920,16 @@ decode_line_info (unit) int end_sequence = 0, need_low_pc = 1; bfd_vma low_pc = 0; - /* Decode the table. */ + /* Decode the table. */ while (! end_sequence) { op_code = read_1_byte (abfd, line_ptr); line_ptr += 1; + switch (op_code) { case DW_LNS_extended_op: - line_ptr += 1; /* ignore length */ + line_ptr += 1; /* Ignore length. */ extended_op = read_1_byte (abfd, line_ptr); line_ptr += 1; switch (extended_op) @@ -1025,12 +1026,12 @@ decode_line_info (unit) address += read_2_bytes (abfd, line_ptr); line_ptr += 2; break; - default: /* special operand */ + default: /* Special operand. */ adj_opcode = op_code - lh.opcode_base; address += (adj_opcode / lh.line_range) * lh.minimum_instruction_length; line += lh.line_base + (adj_opcode % lh.line_range); - /* append row to matrix using current values */ + /* Append row to matrix using current values. */ add_line_info (table, address, filename, line, column, 0); basic_block = 1; if (need_low_pc) @@ -1045,10 +1046,9 @@ decode_line_info (unit) return table; } - /* If ADDR is within TABLE set the output parameters and return true, otherwise return false. The output parameters, FILENAME_PTR and - LINENUMBER_PTR, are pointers to the objects to be filled in. */ + LINENUMBER_PTR, are pointers to the objects to be filled in. */ static boolean lookup_address_in_line_info_table (table, @@ -1084,20 +1084,16 @@ lookup_address_in_line_info_table (table, return false; } +/* Function table functions. */ - - -/* Function table functions. */ - -struct funcinfo { +struct funcinfo +{ struct funcinfo *prev_func; - char* name; bfd_vma low; bfd_vma high; }; - /* If ADDR is within TABLE, set FUNCTIONNAME_PTR, and return true. */ static boolean @@ -1124,14 +1120,10 @@ lookup_address_in_function_table (table, return false; } - - - -/* DWARF2 Compilation unit functions. */ - +/* DWARF2 Compilation unit functions. */ /* Scan over each die in a comp. unit looking for functions to add - to the function table. */ + to the function table. */ static boolean scan_unit_for_functions (unit) @@ -1230,11 +1222,6 @@ scan_unit_for_functions (unit) return true; } - - - - - /* Parse a DWARF2 compilation unit starting at INFO_PTR. This includes the compilation unit header that proceeds the DIE's, but does not include the length field that preceeds each compilation @@ -1299,7 +1286,7 @@ parse_comp_unit (abfd, info_ptr, end_ptr, abbrev_length) return 0; } - /* Read the abbrevs for this compilation unit into a table */ + /* Read the abbrevs for this compilation unit into a table. */ abbrevs = read_abbrevs (abfd, abbrev_offset); if (! abbrevs) return 0; @@ -1379,11 +1366,7 @@ parse_comp_unit (abfd, info_ptr, end_ptr, abbrev_length) return unit; } - - - - -/* Return true if UNIT contains the address given by ADDR. */ +/* Return true if UNIT contains the address given by ADDR. */ static boolean comp_unit_contains_address (unit, addr) @@ -1403,10 +1386,10 @@ comp_unit_contains_address (unit, addr) arange = arange->next; } while (arange); + return 0; } - /* If UNIT contains ADDR, set the output parameters to the values for the line containing ADDR. The output parameters, FILENAME_PTR, FUNCTIONNAME_PTR, and LINENUMBER_PTR, are pointers to the objects @@ -1463,6 +1446,43 @@ comp_unit_find_nearest_line (unit, addr, return line_p || func_p; } +/* Locate a section in a BFD containing debugging info. The search starts from the + section after AFTER_SEC, or from the first section in the BFD if AFTER_SEC is + NULL. The search works by examining the names of the sections. There are two + permissiable names. The first is .debug_info. This is the standard DWARF2 name. + The second is a prefix .gnu.linkonce.wi. This is a variation on the .debug_info + section which has a checksum describing the contents appended onto the name. This + allows the linker to identify and discard duplicate debugging sections for + different compilation units. */ +#define DWARF2_DEBUG_INFO ".debug_info" +#define GNU_LINKONCE_INFO ".gnu.linkonce.wi." + +static asection * +find_debug_info (abfd, after_sec) + bfd * abfd; + asection * after_sec; +{ + asection * msec; + + if (after_sec) + msec = after_sec->next; + else + msec = abfd->sections; + + while (msec) + { + if (strcmp (msec->name, DWARF2_DEBUG_INFO) == 0) + return msec; + + if (strncmp (msec->name, GNU_LINKONCE_INFO, strlen (GNU_LINKONCE_INFO)) == 0) + return msec; + + msec = msec->next; + } + + return NULL; +} + /* The DWARF2 version of find_nearest line. Return true if the line is found without error. ADDR_SIZE is the number of bytes in the initial .debug_info length field and in the abbreviation offset. @@ -1490,12 +1510,10 @@ _bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset, We keep a list of all the previously read compilation units, and a pointer to the next un-read compilation unit. Check the - previously read units before reading more. - */ - + previously read units before reading more. */ struct dwarf2_debug *stash = elf_tdata (abfd)->dwarf2_find_line_info; - /* What address are we looking for? */ + /* What address are we looking for? */ bfd_vma addr = offset + section->vma; struct comp_unit* each; @@ -1513,71 +1531,84 @@ _bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset, if (! stash) { + unsigned long total_size; asection *msec; - unsigned long size; - + stash = elf_tdata (abfd)->dwarf2_find_line_info = (struct dwarf2_debug*) bfd_zalloc (abfd, sizeof (struct dwarf2_debug)); - if (! stash) return false; - - msec = bfd_get_section_by_name (abfd, ".debug_info"); + + msec = find_debug_info (abfd, NULL); if (! msec) - { - /* No dwarf2 info. Note that at this point the stash - has been allocated, but contains zeros, this lets - future calls to this function fail quicker. */ - return false; - } - - size = msec->_raw_size; - if (size == 0) - return false; - - stash->info_ptr = (char *) bfd_alloc (abfd, size); - - if (! stash->info_ptr) + /* No dwarf2 info. Note that at this point the stash + has been allocated, but contains zeros, this lets + future calls to this function fail quicker. */ return false; - if (! bfd_get_section_contents (abfd, msec, stash->info_ptr, 0, size)) + /* There can be more than one DWARF2 info section in a BFD these days. + Read them all in and produce one large stash. We do this in two + passes - in the first pass we just accumulate the section sizes. + In the second pass we read in the section's contents. The allows + us to avoid reallocing the data as we add sections to the stash. */ + for (total_size = 0; msec; msec = find_debug_info (abfd, msec)) + total_size += msec->_raw_size; + + stash->info_ptr = (char *) bfd_alloc (abfd, total_size); + if (stash->info_ptr == NULL) + return false; + + stash->info_ptr_end = stash->info_ptr; + + for (msec = find_debug_info (abfd, NULL); + msec; + msec = find_debug_info (abfd, msec)) { - stash->info_ptr = 0; - return false; + unsigned long size; + unsigned long start; + + size = msec->_raw_size; + if (size == 0) + continue; + + start = stash->info_ptr_end - stash->info_ptr; + + if (! bfd_get_section_contents (abfd, msec, stash->info_ptr + start, 0, size)) + continue; + + stash->info_ptr_end = stash->info_ptr + start + size; } - 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 (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... - - For now, this means that disassembling object files (as - opposed to fully executables) does not always work as well as - we would like. */ + BFD_ASSERT (stash->info_ptr_end = stash->info_ptr + total_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 (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... + + 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 - (or that an error occured while setting up the stash). */ - + (or that an error occured while setting up the stash). */ if (! stash->info_ptr) return false; - /* Check the previously read comp. units first. */ - + /* Check the previously read comp. units first. */ 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); - /* Read each remaining comp. units checking each as they are read. */ + /* Read each remaining comp. units checking each as they are read. */ while (stash->info_ptr < stash->info_ptr_end) { struct comp_unit* each; @@ -1606,7 +1637,7 @@ _bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset, 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. */ + address. */ if (each->arange.high > 0) { if (comp_unit_contains_address (each, addr)) @@ -1630,5 +1661,3 @@ _bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset, return false; } - -/* end of file */