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-rw-r--r--bfd/dwarf2.c295
1 files changed, 224 insertions, 71 deletions
diff --git a/bfd/dwarf2.c b/bfd/dwarf2.c
index 385bf82..888757e 100644
--- a/bfd/dwarf2.c
+++ b/bfd/dwarf2.c
@@ -1,5 +1,5 @@
/* DWARF 2 support.
- Copyright 1994, 1995, 1996, 1997, 1998 Free Software Foundation, Inc.
+ Copyright 1994, 95, 96, 97, 98, 1999 Free Software Foundation, Inc.
Adapted from gdb/dwarf2read.c by Gavin Koch of Cygnus Solutions
(gavin@cygnus.com).
@@ -99,8 +99,16 @@ struct dwarf2_debug {
/* Length of the loaded .debug_abbrev section. */
unsigned long dwarf_abbrev_size;
+
+ /* Buffer for decode_line_info. */
+ char *dwarf_line_buffer;
};
+struct arange {
+ struct arange *next;
+ bfd_vma low;
+ bfd_vma high;
+};
/* A minimal decoding of DWARF2 compilation units. We only decode
@@ -116,8 +124,7 @@ struct comp_unit {
/* The lowest and higest addresses contained in this compilation
unit as specified in the compilation unit header. */
- bfd_vma low;
- bfd_vma high;
+ struct arange arange;
/* The DW_AT_name attribute (for error messages). */
char* name;
@@ -163,7 +170,7 @@ struct comp_unit {
static unsigned int
read_1_byte (abfd, buf)
- bfd *abfd;
+ bfd *abfd ATTRIBUTE_UNUSED;
char *buf;
{
return bfd_get_8 (abfd, (bfd_byte *) buf);
@@ -171,7 +178,7 @@ read_1_byte (abfd, buf)
static int
read_1_signed_byte (abfd, buf)
- bfd *abfd;
+ bfd *abfd ATTRIBUTE_UNUSED;
char *buf;
{
return bfd_get_signed_8 (abfd, (bfd_byte *) buf);
@@ -231,9 +238,9 @@ read_8_bytes (abfd, buf)
static char *
read_n_bytes (abfd, buf, size)
- bfd * abfd;
+ bfd *abfd ATTRIBUTE_UNUSED;
char *buf;
- unsigned int size;
+ unsigned int size ATTRIBUTE_UNUSED;
{
/* If the size of a host char is 8 bits, we can return a pointer
to the buffer, otherwise we have to copy the data to a buffer
@@ -243,7 +250,7 @@ read_n_bytes (abfd, buf, size)
static char *
read_string (abfd, buf, bytes_read_ptr)
- bfd *abfd;
+ bfd *abfd ATTRIBUTE_UNUSED;
char *buf;
unsigned int *bytes_read_ptr;
{
@@ -261,7 +268,7 @@ read_string (abfd, buf, bytes_read_ptr)
static unsigned int
read_unsigned_leb128 (abfd, buf, bytes_read_ptr)
- bfd *abfd;
+ bfd *abfd ATTRIBUTE_UNUSED;
char *buf;
unsigned int *bytes_read_ptr;
{
@@ -291,8 +298,8 @@ read_unsigned_leb128 (abfd, buf, bytes_read_ptr)
static int
read_signed_leb128 (abfd, buf, bytes_read_ptr)
- bfd * abfd;
- char * buf;
+ bfd *abfd ATTRIBUTE_UNUSED;
+ char *buf;
unsigned int * bytes_read_ptr;
{
int result;
@@ -423,7 +430,7 @@ read_abbrevs (abfd, offset)
}
stash->dwarf_abbrev_size = bfd_get_section_size_before_reloc (msec);
- stash->dwarf_abbrev_buffer = (unsigned char*) bfd_alloc (abfd, stash->dwarf_abbrev_size);
+ stash->dwarf_abbrev_buffer = (char*) bfd_alloc (abfd, stash->dwarf_abbrev_size);
if (! stash->dwarf_abbrev_buffer)
return 0;
@@ -604,6 +611,10 @@ read_attribute (attr, abbrev, unit, info_ptr)
DW_UNSND (attr) = read_4_bytes (abfd, info_ptr);
info_ptr += 4;
break;
+ case DW_FORM_ref8:
+ DW_UNSND (attr) = read_8_bytes (abfd, info_ptr);
+ info_ptr += 8;
+ break;
case DW_FORM_ref_udata:
DW_UNSND (attr) = read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
info_ptr += bytes_read;
@@ -631,6 +642,7 @@ struct line_info {
char* filename;
unsigned int line;
unsigned int column;
+ int end_sequence; /* end of (sequential) code sequence */
};
struct fileinfo {
@@ -653,12 +665,13 @@ 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 +683,7 @@ 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 +691,16 @@ 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;
@@ -690,6 +713,50 @@ concat_filename (table, file)
}
}
+static void
+arange_add (unit, low_pc, high_pc)
+ struct comp_unit *unit;
+ bfd_vma low_pc;
+ bfd_vma high_pc;
+{
+ struct arange *arange;
+
+ /* first see if we can cheaply extend an existing range: */
+ arange = &unit->arange;
+ do
+ {
+ if (low_pc == arange->high)
+ {
+ arange->high = high_pc;
+ return;
+ }
+ if (high_pc == arange->low)
+ {
+ arange->low = low_pc;
+ return;
+ }
+ arange = arange->next;
+ }
+ while (arange);
+
+ if (unit->arange.high == 0)
+ {
+ /* 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: */
+ arange = bfd_zalloc (unit->abfd, sizeof (*arange));
+ arange->low = low_pc;
+ arange->high = high_pc;
+
+ arange->next = unit->arange.next;
+ unit->arange.next = arange;
+}
+
/* Decode the line number information for UNIT. */
static struct line_info_table*
@@ -698,7 +765,7 @@ decode_line_info (unit)
{
bfd *abfd = unit->abfd;
- static char* dwarf_line_buffer = 0;
+ struct dwarf2_debug *stash;
struct line_info_table* table;
@@ -709,7 +776,9 @@ decode_line_info (unit)
char *cur_file, *cur_dir;
unsigned char op_code, extended_op, adj_opcode;
- if (! dwarf_line_buffer)
+ stash = elf_tdata (abfd)->dwarf2_find_line_info;
+
+ if (! stash->dwarf_line_buffer)
{
asection *msec;
unsigned long size;
@@ -723,12 +792,12 @@ decode_line_info (unit)
}
size = bfd_get_section_size_before_reloc (msec);
- dwarf_line_buffer = (unsigned char*) bfd_alloc (abfd, size);
- if (! dwarf_line_buffer)
+ stash->dwarf_line_buffer = (char *) bfd_alloc (abfd, size);
+ if (! stash->dwarf_line_buffer)
return 0;
if (! bfd_get_section_contents (abfd, msec,
- dwarf_line_buffer, 0,
+ stash->dwarf_line_buffer, 0,
size))
return 0;
@@ -747,7 +816,10 @@ decode_line_info (unit)
table->num_dirs = 0;
table->dirs = NULL;
- line_ptr = dwarf_line_buffer + unit->line_offset;
+ table->files = NULL;
+ table->last_line = NULL;
+
+ line_ptr = stash->dwarf_line_buffer + unit->line_offset;
/* read in the prologue */
lh.total_length = read_4_bytes (abfd, line_ptr);
@@ -830,7 +902,8 @@ decode_line_info (unit)
unsigned int column = 0;
int is_stmt = lh.default_is_stmt;
int basic_block = 0;
- int end_sequence = 0;
+ int end_sequence = 0, need_low_pc = 1;
+ bfd_vma low_pc = 0;
/* Decode the table. */
while (! end_sequence)
@@ -847,7 +920,14 @@ 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);
+ if (need_low_pc)
+ {
+ need_low_pc = 0;
+ low_pc = address;
+ }
+ arange_add (unit, low_pc, address);
break;
case DW_LNE_set_address:
address = read_address (unit, line_ptr);
@@ -884,8 +964,13 @@ 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;
+ if (need_low_pc)
+ {
+ need_low_pc = 0;
+ low_pc = address;
+ }
break;
case DW_LNS_advance_pc:
address += lh.minimum_instruction_length
@@ -918,7 +1003,8 @@ 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);
@@ -930,8 +1016,13 @@ 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 (need_low_pc)
+ {
+ need_low_pc = 0;
+ low_pc = address;
+ }
}
}
}
@@ -954,21 +1045,25 @@ 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;
@@ -1125,24 +1220,27 @@ scan_unit_for_functions (unit)
-/* 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 unit header.
- END_PTR points one past the end of this comp unit.
+/* 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
+ unit header. END_PTR points one past the end of this comp unit.
+ If ABBREV_LENGTH is 0, then the length of the abbreviation offset
+ is assumed to be four bytes. Otherwise, it it is the size given.
This routine does not read the whole compilation unit; only enough
to get to the line number information for the compilation unit. */
static struct comp_unit *
-parse_comp_unit (abfd, info_ptr, end_ptr)
+parse_comp_unit (abfd, info_ptr, end_ptr, abbrev_length)
bfd* abfd;
char* info_ptr;
char* end_ptr;
+ unsigned int abbrev_length;
{
struct comp_unit* unit;
unsigned short version;
- unsigned int abbrev_offset;
+ unsigned int abbrev_offset = 0;
unsigned char addr_size;
struct abbrev_info** abbrevs;
@@ -1152,8 +1250,14 @@ parse_comp_unit (abfd, info_ptr, end_ptr)
version = read_2_bytes (abfd, info_ptr);
info_ptr += 2;
- abbrev_offset = read_4_bytes (abfd, info_ptr);
- info_ptr += 4;
+ BFD_ASSERT (abbrev_length == 0
+ || abbrev_length == 4
+ || abbrev_length == 8);
+ if (abbrev_length == 0 || abbrev_length == 4)
+ abbrev_offset = read_4_bytes (abfd, info_ptr);
+ else if (abbrev_length == 8)
+ abbrev_offset = read_8_bytes (abfd, info_ptr);
+ info_ptr += abbrev_length;
addr_size = read_1_byte (abfd, info_ptr);
info_ptr += 1;
@@ -1228,11 +1332,11 @@ parse_comp_unit (abfd, info_ptr, end_ptr)
break;
case DW_AT_low_pc:
- unit->low = DW_ADDR (&attr);
+ unit->arange.low = DW_ADDR (&attr);
break;
case DW_AT_high_pc:
- unit->high = DW_ADDR (&attr);
+ unit->arange.high = DW_ADDR (&attr);
break;
case DW_AT_comp_dir:
@@ -1271,8 +1375,20 @@ comp_unit_contains_address (unit, addr)
struct comp_unit* unit;
bfd_vma addr;
{
- return ! unit->error
- && (addr >= unit->low && addr <= unit->high);
+ struct arange *arange;
+
+ if (unit->error)
+ return 0;
+
+ arange = &unit->arange;
+ do
+ {
+ if (addr >= arange->low && addr < arange->high)
+ return 1;
+ arange = arange->next;
+ }
+ while (arange);
+ return 0;
}
@@ -1332,19 +1448,25 @@ comp_unit_find_nearest_line (unit, addr,
return line_p || func_p;
}
-/* The DWARF2 version of find_nearest line.
- Return true if the line is found without error. */
+/* 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.
+ You may use zero to indicate that the default value should be
+ used. */
boolean
_bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset,
- filename_ptr, functionname_ptr, linenumber_ptr)
+ filename_ptr, functionname_ptr,
+ linenumber_ptr,
+ addr_size)
bfd *abfd;
asection *section;
- asymbol **symbols;
+ asymbol **symbols ATTRIBUTE_UNUSED;
bfd_vma offset;
const char **filename_ptr;
const char **functionname_ptr;
unsigned int *linenumber_ptr;
+ unsigned int addr_size;
{
/* Read each compilation unit from the section .debug_info, and check
to see if it contains the address we are searching for. If yes,
@@ -1367,6 +1489,13 @@ _bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset,
*functionname_ptr = NULL;
*linenumber_ptr = 0;
+ /* The DWARF2 spec says that the initial length field, and the
+ offset of the abbreviation table, should both be 4-byte values.
+ However, some compilers do things differently. */
+ if (addr_size == 0)
+ addr_size = 4;
+ BFD_ASSERT (addr_size == 4 || addr_size == 8);
+
if (! stash)
{
asection *msec;
@@ -1404,14 +1533,20 @@ _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
@@ -1423,27 +1558,28 @@ _bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset,
/* 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);
- }
+ 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. */
while (stash->info_ptr < stash->info_ptr_end)
{
struct comp_unit* each;
- unsigned int length;
+ bfd_vma length;
+ boolean found;
- length = read_4_bytes (abfd, stash->info_ptr);
- stash->info_ptr += 4;
+ if (addr_size == 4)
+ length = read_4_bytes (abfd, stash->info_ptr);
+ else
+ length = read_8_bytes (abfd, stash->info_ptr);
+ stash->info_ptr += addr_size;
if (length > 0)
{
each = parse_comp_unit (abfd, stash->info_ptr,
- stash->info_ptr + length);
+ stash->info_ptr + length,
+ addr_size);
stash->info_ptr += length;
if (each)
@@ -1451,11 +1587,28 @@ _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->arange.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;
+ }
}
}
}
generated by cgit v1.1 at 2024-10-02 07:19:45 +0000