[PATCH] DWARF support for .debug_loc offsets

Petr Sorfa
2002-07-11T16:24:51Z

[-- Attachment #1: Type: text/plain, Size: 1094 bytes --]

Hi,

This patch provides support for offsets into .debug_loc.

The patch does not include .debug_loc support in read_tag_string_type()
as the DW_AT_string_length attribute is currently being misused by GCC
(it uses it to hold the length, rather than the location to the length)
and GDB supports the incorrect form.

There is a second part of this patch which is dependent on FORTRAN95
support of modules and will be released later.

2002-07-11 Petr Sorfa (petrs@caldera.com)

* dwarf2read.c (dwarf2_invalid_attrib_class): New
complaint for invalid attribute class or form.
(read_func_scope): DW_AT_frame_base
attribute now supports .debug_loc offsets.
(dwarf2_add_member_fn): DW_AT_vtable_elem_location
attribute now supports .debug_loc offsets.
(read_common_block): DW_AT_location attribute
now supports .debug_loc offsets.
(read_partial_die): DW_AT_location attribute now
supports .debug_loc offsets.
(new_symbol): DW_AT_external now supports
.debug_loc offsets.

[-- Attachment #2: debug_loc_no_dep.patch --]
[-- Type: text/plain, Size: 9495 bytes --]

Index: dwarf2read.c
===================================================================
RCS file: /cvs/src/src/gdb/dwarf2read.c,v
retrieving revision 1.60
diff -c -p -r1.60 dwarf2read.c
*** dwarf2read.c 22 Jun 2002 00:05:59 -0000 1.60
--- dwarf2read.c 11 Jul 2002 16:11:08 -0000
*************** static struct complaint dwarf2_macro_spa
*** 658,663 ****
--- 658,667 ----
{
"macro definition contains spaces in formal argument list:\n`%s'", 0, 0
};
+ static struct complaint dwarf2_invalid_attrib_class =
+ {
+ "invalid attribute class or form for '%s' in '%s'", 0, 0
+ };

/* local function prototypes */

*************** read_func_scope (struct die_info *die, s
*** 1870,1876 ****
attr = dwarf_attr (die, DW_AT_frame_base);
if (attr)
{
! CORE_ADDR addr = decode_locdesc (DW_BLOCK (attr), objfile, cu_header);
if (isderef)
complain (&dwarf2_unsupported_at_frame_base, name);
else if (isreg)
--- 1874,1904 ----
attr = dwarf_attr (die, DW_AT_frame_base);
if (attr)
{
! CORE_ADDR addr;
!
! /* Support the .debug_loc offsets */
! if (attr->form == DW_FORM_block1
! || attr->form == DW_FORM_block2
! || attr->form == DW_FORM_block4
! || attr->form == DW_FORM_block)
! {
! addr = decode_locdesc (DW_BLOCK (attr), objfile, cu_header);
! }
! else if (attr->form == DW_FORM_data4 || attr->form == DW_FORM_data8)
! {
! int bytes_read;
!
! /* Offset from .debug_loc */
! addr = read_address (objfile->obfd,
! (char *)(DW_UNSND (attr) + dwarf_loc_offset),
! cu_header, &bytes_read);
! }
! else
! {
! complain (&dwarf2_invalid_attrib_class, "DW_AT_frame_base", name);
! addr = 0;
! }
!
if (isderef)
complain (&dwarf2_unsupported_at_frame_base, name);
else if (isreg)
*************** dwarf2_add_member_fn (struct field_info
*** 2348,2354 ****
/* Get index in virtual function table if it is a virtual member function. */
attr = dwarf_attr (die, DW_AT_vtable_elem_location);
if (attr)
! fnp->voffset = decode_locdesc (DW_BLOCK (attr), objfile, cu_header) + 2;
}

/* Create the vector of member function fields, and attach it to the type. */
--- 2376,2405 ----
/* Get index in virtual function table if it is a virtual member function. */
attr = dwarf_attr (die, DW_AT_vtable_elem_location);
if (attr)
! {
! /* Support the .debug_loc offsets */
! if (attr->form == DW_FORM_block1
! || attr->form == DW_FORM_block2
! || attr->form == DW_FORM_block4
! || attr->form == DW_FORM_block)
! {
! fnp->voffset = decode_locdesc (DW_BLOCK (attr), objfile, cu_header) + 2;
! }
! else if (attr->form == DW_FORM_data4 || attr->form == DW_FORM_data8)
! {
! int bytes_read;
!
! /* Offset from .debug_loc */
! fnp->voffset = read_address (objfile->obfd,
! (char *)(DW_UNSND (attr) + dwarf_loc_offset),
! cu_header, &bytes_read) + 2;
! }
! else
! {
! complain (&dwarf2_invalid_attrib_class, "DW_AT_vtable_elem_location",
! fieldname);
! }
! }
}

/* Create the vector of member function fields, and attach it to the type. */
*************** read_common_block (struct die_info *die,
*** 2812,2818 ****
attr = dwarf_attr (die, DW_AT_location);
if (attr)
{
! base = decode_locdesc (DW_BLOCK (attr), objfile, cu_header);
}
if (die->has_children)
{
--- 2863,2890 ----
attr = dwarf_attr (die, DW_AT_location);
if (attr)
{
! /* Support the .debug_loc offsets */
! if (attr->form == DW_FORM_block1
! || attr->form == DW_FORM_block2
! || attr->form == DW_FORM_block4
! || attr->form == DW_FORM_block)
! {
! base = decode_locdesc (DW_BLOCK (attr), objfile, cu_header);
! }
! else if (attr->form == DW_FORM_data4 || attr->form == DW_FORM_data8)
! {
! int bytes_read;
!
! /* Offset from .debug_loc */
! base = read_address (objfile->obfd,
! (char *)(DW_UNSND (attr) + dwarf_loc_offset),
! cu_header, &bytes_read);
! }
! else
! {
! complain (&dwarf2_invalid_attrib_class, "DW_AT_location",
! "common block member");
! }
}
if (die->has_children)
{
*************** read_partial_die (struct partial_die_inf
*** 3458,3464 ****
part_die->highpc = DW_ADDR (&attr);
break;
case DW_AT_location:
! part_die->locdesc = DW_BLOCK (&attr);
break;
case DW_AT_language:
part_die->language = DW_UNSND (&attr);
--- 3530,3557 ----
part_die->highpc = DW_ADDR (&attr);
break;
case DW_AT_location:
! /* Support the .debug_loc offsets */
! if (attr.form == DW_FORM_block1
! || attr.form == DW_FORM_block2
! || attr.form == DW_FORM_block4
! || attr.form == DW_FORM_block)
! {
! part_die->locdesc = DW_BLOCK (&attr);
! }
! else if (attr.form == DW_FORM_data4 || attr.form == DW_FORM_data8)
! {
! /* Offset from .debug_loc */
! int bytes_read;
!
! part_die->locdesc = (struct dwarf_block *)read_address (abfd,
! (char *)(DW_UNSND (&attr) + dwarf_loc_offset),
! cu_header, &bytes_read);
! }
! else
! {
! complain (&dwarf2_invalid_attrib_class, "DW_AT_location",
! "partial symbol information");
! }
break;
case DW_AT_language:
part_die->language = DW_UNSND (&attr);
*************** new_symbol (struct die_info *die, struct
*** 4606,4613 ****
attr2 = dwarf_attr (die, DW_AT_external);
if (attr2 && (DW_UNSND (attr2) != 0))
{
! SYMBOL_VALUE_ADDRESS (sym) =
! decode_locdesc (DW_BLOCK (attr), objfile, cu_header);
add_symbol_to_list (sym, &global_symbols);

/* In shared libraries the address of the variable
--- 4699,4729 ----
attr2 = dwarf_attr (die, DW_AT_external);
if (attr2 && (DW_UNSND (attr2) != 0))
{
! /* Support the .debug_loc offsets */
! if (attr->form == DW_FORM_block1
! || attr->form == DW_FORM_block2
! || attr->form == DW_FORM_block4
! || attr->form == DW_FORM_block)
! {
! SYMBOL_VALUE_ADDRESS (sym) =
! decode_locdesc (DW_BLOCK (attr), objfile, cu_header);
! }
! else if (attr->form == DW_FORM_data4
! || attr->form == DW_FORM_data8)
! {
! int bytes_read;
!
! /* Offset from .debug_loc */
! SYMBOL_VALUE_ADDRESS (sym) =
! read_address (objfile->obfd,
! (char *)(DW_UNSND (attr) + dwarf_loc_offset),
! cu_header, &bytes_read);
! }
! else
! {
! complain (&dwarf2_invalid_attrib_class, "DW_AT_location",
! "external variable");
! }
add_symbol_to_list (sym, &global_symbols);

/* In shared libraries the address of the variable
*************** new_symbol (struct die_info *die, struct
*** 4630,4637 ****
}
else
{
! SYMBOL_VALUE (sym) = addr =
! decode_locdesc (DW_BLOCK (attr), objfile, cu_header);
add_symbol_to_list (sym, list_in_scope);
if (optimized_out)
{
--- 4746,4777 ----
}
else
{
! /* Support the .debug_loc offsets */
! if (attr->form == DW_FORM_block1
! || attr->form == DW_FORM_block2
! || attr->form == DW_FORM_block4
! || attr->form == DW_FORM_block)
! {
! SYMBOL_VALUE (sym) = addr =
! decode_locdesc (DW_BLOCK (attr), objfile, cu_header);
! }
! else if (attr->form == DW_FORM_data4
! || attr->form == DW_FORM_data8)
! {
! int bytes_read;
!
! /* Offset from .debug_loc */
! SYMBOL_VALUE (sym) = addr =
! read_address (objfile->obfd,
! (char *)(DW_UNSND (attr) + dwarf_loc_offset),
! cu_header, &bytes_read);
! }
! else
! {
! complain (&dwarf2_invalid_attrib_class, "DW_AT_location",
! "external variable");
! addr = 0;
! }
add_symbol_to_list (sym, list_in_scope);
if (optimized_out)
{