8 Commits

Author SHA1 Message Date
048fde1ef4 DWARFv5: Handle DW_MACRO_define_strx and DW_MACRO_undef_strx macro entries.
GDB complaints "During symbol reading: unrecognized DW_MACFINO
opcode 0xb" with the testcase given below. Clang is emitting
DW_MACRO_define_strx and DW_MACRO_undef_strx entries in .debug_macro
section which are not supported in GDB. This patch handles them.

DW_MACRO_define_strx and DW_MACRO_undef_strx are added in DWARFv5.
They have two operands. The first operand encodes the line number of
the #define or #undef macro directive. The second operand identifies
a string; it is represented using an unsigned LEB128 encoded value,
which is interpreted as a zero-based index into an array of offsets
in the .debug_str_offsets section. This is as per the section 6.3.2.1
of Dwarf Debugging Information Format Version 5.

Test case used:
 #define MAX_SIZE 10
int main(void)
{
   int size = 0;
   size = size + MAX_SIZE;

   printf("\n The value of size is [%d]\n",size);

   return 0;
}

clang -gdwarf-5 -fdebug-macro  macro.c -o macro.out

Before the patch:

gdb/new_gdb/binutils-gdb/build/bin/gdb -q macro.out -ex "set complaints 1" -ex "start"
Reading symbols from macro.out...
During symbol reading: unrecognized DW_MACFINO opcode 0xb
Temporary breakpoint 1 at 0x4004df: file macro.c, line 7.
Starting program: /home/nitika/workspace/macro.out

Temporary breakpoint 1, main () at macro.c:7
7          int size = 0;
(gdb)

Tested by running the testsuite before and after the patch with
 -gdwarf-5 and there is no increase in the number of test cases
that fails. Used clang 11.0.0.

gdb/ChangeLog:

	* dwarf2/macro.c (dwarf_decode_macro_bytes): Handle DW_MACRO_define_strx
	and DW_MACRO_undef_strx.
	(dwarf_decode_macros): Likewise
	* dwarf2/read.c (dwarf_decode_macros): Pass str_offsets_base in the parameters
	which is the value of DW_AT_str_offsets_base.
	* dwarf2/macro.h (dwarf_decode_macros): Modify the definition to include
	str_offsets_base.
2020-10-02 12:27:45 +05:30
976ca31673 gdb: rename dwarf2_per_objfile variables/fields to per_objfile
While doing the psymtab-sharing patchset, I avoided renaming variables
unnecessarily to avoid adding noise to patches, but I'd like to do it
now.  Basically, we have these dwarf2 per-something structures:

  - dwarf2_per_objfile
  - dwarf2_per_bfd
  - dwarf2_per_cu_data

I named the instances of dwarf2_per_bfd `per_bfd` and most of instances
of dwarf2_per_cu_data are called `per_cu`.  Most pre-existing instances
of dwarf2_per_objfile are named `dwarf2_per_objfile`.  For consistency
with the other type, I'd like to rename them to just `per_objfile`.  The
`dwarf2_` prefix is superfluous, since it's already clear we are in
dwarf2 code.  It also helps reducing the line wrapping by saving 7
precious columns.

gdb/ChangeLog:

	* dwarf2/comp-unit.c, dwarf2/comp-unit.h, dwarf2/index-cache.c,
	dwarf2/index-cache.h, dwarf2/index-write.c,
	dwarf2/index-write.h, dwarf2/line-header.c,
	dwarf2/line-header.h, dwarf2/macro.c, dwarf2/macro.h,
	dwarf2/read.c, dwarf2/read.h: Rename struct dwarf2_per_objfile
	variables and fields from `dwarf2_per_objfile` to just
	`per_objfile` throughout.

Change-Id: I3c45cdcc561265e90df82cbd36b4b4ef2fa73aef
2020-05-29 15:15:10 -04:00
c3699833af Make dwarf2_get_dwz_file take a dwarf2_per_bfd
This allows removing a per_bfd->dwarf2_per_objfile reference in
get_abbrev_section_for_cu.

This requires saving the bfd in dwarf2_per_bfd.  The constructor of
dwarf2_per_bfd already accepts the bfd, so it's just a matter of saving
it in a field.

I replaced uses of objfile_name with bfd_get_filename, which should be
equivalent in this case.

gdb/ChangeLog:

	* dwarf2/read.h (struct dwarf2_per_bfd) <obfd>: New member.
	(dwarf2_get_dwz_file): Replace parameter with dwarf2_per_bfd.
	* dwarf2/read.c (dwarf2_per_bfd::dwarf2_per_bfd): Assign obfd
	field.
	(dwarf2_get_dwz_file): Replace parameter with dwarf2_per_bfd.
	(create_cus_from_index): Update.
	(dwarf2_read_gdb_index): Update.
	(create_cus_from_debug_names): Update.
	(dwarf2_read_debug_names): Update.
	(get_abbrev_section_for_cu): Update.
	(create_all_comp_units): Update.
	(read_attribute_value): Update.
	(get_debug_line_section): Update.
	* dwarf2/index-cache.c (index_cache::store): Update.
	* dwarf2/index-write.c (save_gdb_index_command): Update.
	* dwarf2/macro.c (dwarf_decode_macro_bytes): Update.

Change-Id: Ifb23f55dda93c499aae57b6a9aff9c6ff9d2f45f
2020-05-27 11:15:54 -04:00
5989a64ed5 Split dwarf2_per_objfile into dwarf2_per_objfile and dwarf2_per_bfd
This is the first step of splitting dwarf2_per_objfile in two, one
structure for objfile-independent data (dwarf2_per_bfd) and one for
objfile-dependent data (dwarf2_per_objfile).

The existing dwarf2_per_objfile is renamed dwarf2_per_bfd, and a new
dwarf2_per_objfile type is introduced, which sits "in between" the
objfile and dwarf2_per_bfd.

So where we had this before:

  objfile -> dwarf2_per_objfile (*)

we now have this:

  objfile -> dwarf2_per_objfile -> dwarf2_per_bfd (*)

(*) Note that the dwarf2_per_objfile in the former corresponds to
the dwarf2_per_bfd in the latter.

I've done the minimal amount of changes in this patch: following patches
will incrementally move things that are not actually shareable between
objfiles from dwarf2_per_bfd to dwarf2_per_objfile.

Most references to dwarf2_per_objfile objects are changed to
dwarf2_per_objfile->per_bfd.  To avoid many of these replacements, which
would have to be reverted later anyway, I've moved right away the
objfile backlink to the new dwarf2_per_objfile structure in this patch.
I've also moved the read_line_string method, since it references the
objfile backlink, and it's actually not difficult to move.

Once the moves are completed, multiple dwarf2_per_objfile sharing the
same BFD will point to the same single instance of dwarf2_per_bfd (as
long as they don't require relocation).

dwarf2_has_info, where we create these objects, is updated to the new
architecture.

I've had to change the get_gdb_index_contents_ftype typedef and related
functions.  The parameter type was changed from dwarf2_per_objfile to
dwarf2_per_bfd, otherwise the template wouldn't work.

Please excuse the terse ChangeLog entry, I have not listed all the
functions where dwarf2_per_objfile has been changed to
dwarf2_per_objfile->per_bfd.  It would take a considerable amount of
time and would not really be useful in the end.

gdb/ChangeLog:

	* dwarf2/read.h (dwarf2_per_objfile): Rename to dwarf2_per_bfd,
	then introduce a new dwarf2_per_objfile type.
	<read_line_string>: Move to the new dwarf2_per_objfile type.
	<objfile>: Likewise.
	(dwarf2_per_bfd): Rename dwarf2_per_objfile to this.
	* dwarf2/read.c: Replace references to dwarf2_per_objfile with
	dwarf2_per_objfile->per_bfd.
	(dwarf2_per_objfile::dwarf2_per_objfile): Rename to...
	(dwarf2_per_bfd::dwarf2_per_bfd): ... this.
	(dwarf2_per_objfile::free_cached_comp_units): Rename to...
	(dwarf2_per_bfd::free_cached_comp_units): ... this.
	(dwarf2_has_info): Allocate dwarf2_per_bfd.
	(dwarf2_per_objfile::locate_sections): Rename to...
	(dwarf2_per_bfd::locate_sections): ... this.
	(dwarf2_per_objfile::get_cutu): Rename to...
	(dwarf2_per_bfd::get_cutu): ... this.
	(dwarf2_per_objfile::get_cu): Rename to...
	(dwarf2_per_bfd::get_cu): ... this.
	(dwarf2_per_objfile::get_tu): Rename to...
	(dwarf2_per_bfd::get_tu): ... this.
	(dwarf2_per_objfile::allocate_per_cu): Rename to...
	(dwarf2_per_bfd::allocate_per_cu): ... this.
	(dwarf2_per_objfile::allocate_signatured_type): Rename to...
	(dwarf2_per_bfd::allocate_signatured_type): ... this.
	(get_gdb_index_contents_ftype): Change parameter from
	dwarf2_per_objfile to dwarf2_per_bfd.
	* dwarf2/macro.c, dwarf2/index-write.c: Replace references to
	dwarf2_per_objfile with dwarf2_per_objfile->per_bfd.

Change-Id: I7de7b5d1ce7494aa73bfcf15f719d3c5c46e138c
2020-05-27 11:13:50 -04:00
2ef46c2fbb Trivial fix in dwarf_decode_macro_bytes
One spot in dwarf_decode_macro_bytes could use the existing "objfile"
local variable.

gdb/ChangeLog
2020-03-26  Tom Tromey  <tom@tromey.com>

	* dwarf2/macro.c (dwarf_decode_macro_bytes): Use objfile local
	variable.
2020-03-26 09:28:18 -06:00
4f9c1eda9f Use a const dwarf2_section_info in macro reader
This changes the DWARF macro reader to use a const dwarf2_section_info.

gdb/ChangeLog
2020-03-26  Tom Tromey  <tom@tromey.com>

	* dwarf2/macro.h (dwarf_decode_macros): Make section parameter
	const.
	* dwarf2/macro.c (skip_form_bytes, skip_unknown_opcode)
	(dwarf_decode_macro_bytes, dwarf_decode_macros): Make section
	parameter const.
2020-03-26 09:28:17 -06:00
5a0e026fe1 Use a const line_header in macro reader
This changes the DWARF macro reader to use a const line_header.

gdb/ChangeLog
2020-03-26  Tom Tromey  <tom@tromey.com>

	* dwarf2/read.c (dwarf_decode_macros): Make "lh" const.
	* dwarf2/macro.h (dwarf_decode_macros): Constify "lh" parameter.
	* dwarf2/macro.c (macro_start_file): Constify "lh" parameter.
	(dwarf_decode_macro_bytes, dwarf_decode_macros): Likewise.
2020-03-26 09:28:16 -06:00
c90ec28ae4 Move code to new file dwarf2/macro.c
This moves some more code out of dwarf2/read.c, introducing new files
dwarf2/macro.c and dwarf2/macro.h.

gdb/ChangeLog
2020-03-26  Tom Tromey  <tom@tromey.com>

	* dwarf2/read.c (dwarf2_macro_malformed_definition_complaint)
	(macro_start_file, consume_improper_spaces)
	(parse_macro_definition, skip_form_bytes, skip_unknown_opcode)
	(dwarf_parse_macro_header, dwarf_decode_macro_bytes)
	(dwarf_decode_macros): Move to macro.c.
	* dwarf2/macro.c: New file.
	* dwarf2/macro.h: New file.
	* Makefile.in (COMMON_SFILES): Add dwarf2/macro.c.
2020-03-26 09:28:15 -06:00