On aarch64, we got the following fail:
(gdb) disassemble func
Dump of assembler code for function func:
0x0000000000400730 <+0>: ret
End of assembler dump.^M
(gdb) x/2i func+0^M
0x400730 <func>: ret^M
0x400734 <main>: stp x29, x30, [sp,#-16]!^M
(gdb) FAIL: gdb.dwarf2/dw2-ifort-parameter.exp: x/2i func+0
the pattern in proc function_range expects to match <func+0>, however,
GDB doesn't display the offset when it is zero. This patch is to
adjust the pattern when $func_length is zero.
gdb/testsuite:
2015-02-26 Yao Qi <yao.qi@linaro.org>
* lib/dwarf.exp (function_range): Adjust pattern when $func_length
is zero.
gdb/testsuite/ChangeLog:
* lib/dwarf.exp (Dwarf): Flag an error if a numeric attribute value
is given without an explicit form.
* gdb.dwarf2/arr-subrange.exp: Specify forms for all numeric
attributes.
* gdb.dwarf/corrupt.exp: Ditto.
* gdb.dwarf2/enum-type.exp: Ditto.
* gdb.trace/entry-values.exp: Ditto.
* gdb.trace/unavailable-dwarf-piece.exp: Ditto.
This changes the DWARF assembler to allow comments in a location
expression, and also adds support for a few new opcodes I needed.
gdb/testsuite/ChangeLog
2014-12-12 Tom Tromey <tromey@redhat.com>
* lib/dwarf.exp (_location): Ignore blank lines. Allow comments.
Handle DW_OP_pick, DW_OP_skip, DW_OP_bra.
Dwarf::tu and Dwarf::cu allow selection of units with 64-bit offsets
through an option. When selected, unit size is encoded properly, but
offset to abbreviation unit is still encoded in a 4-byte field. This
patch fixes the problem.
Reproducer:
Dwarf::assemble "blah.s" {
tu {is_64 1 version 4 addr_size 8} 0x1122334455667788 the_type {
type_unit {} { the_type: }
}
cu {is_64 1 version 4 addr_size 8} {
compile_unit {{language @DW_LANG_C}} {}
}
}
gdb/testsuite:
* lib/dwarf.exp (Dwarf::cu, Dwarf::tu): Emit
${_cu_offset_size} bytes abbrev offset.
This patch addes DW macro attributes MACRO_AT_func and MACRO_AT_range
in dwarf assembler, which emits "DW_AT_low_pc func_start addr" and
"DW_AT_high_pc func_end addr". func_start and func_end are computed
automatically by proc function_range.
These two attributes are pseudo attribute or macro attribute, which
means they are not standard dwarf attribute in dwarf spec. Then can
be substituted or expanded to standard attributes or macro attributes.
See details in the comments to them. Dwarf assembler is extended to
handle them.
Now the attributes name/low_pc/high_pc can be replaced with
MACRO_AT_func like this:
subprogram {
{name main}
{low_pc main_start addr}
{high_pc main_end addr}
}
becomes:
subprogram {
{MACRO_AT_func { main ${srcdir}/${subdir}/${srcfile} }}
}
users don't have to worry about the start and end of function main, and
they only need to add a label main_label in main.
gdb/testsuite:
2014-11-14 Yao Qi <yao@codesourcery.com>
* lib/dwarf.exp (function_range): New procedure.
(Dwarf::_handle_macro_at_func): New procedure.
(Dwarf::_handle_macro_at_range): New procedure.
(Dwarf): Handle MACRO_AT_func and MACRO_AT_range.
This patch is to move some code to a new procedure _handle_attribute,
which will be used in my following patches.
gdb/testsuite:
2014-11-14 Yao Qi <yao@codesourcery.com>
* lib/dwarf.exp (_handle_DW_TAG): Move some code to ...
(_handle_attribute): New procedure.
This patch fixes gdb PR symtab/15597.
The bug is that the .gnu_debugaltlink section includes the build-id of
the alt file, but gdb does not use it.
This patch fixes the problem by changing gdb to do what it ought to
always have done: verify the build id of the file found using the
filename in .gnu_debugaltlink; and if that does not match, try to find
the correct debug file using the build-id and debug-file-directory.
This patch touches BFD. Previously, gdb had its own code for parsing
.gnu_debugaltlink; I changed it to use the BFD functions after those
were introduced. However, the BFD functions are incorrect -- they
assume that .gnu_debugaltlink is formatted like .gnu_debuglink.
However, it it is not. Instead, it consists of a file name followed
by the build-id -- no alignment, and the build-id is not a CRC.
Fixing this properly is a bit of a pain. But, because
separate_alt_debug_file_exists just has a FIXME for the build-id case,
I did not fix it properly. Instead I introduced a hack. This leaves
BFD working just as well as it did before my patch.
I'm willing to do something better here but I could use some guidance
as to what. It seems that the build-id code in BFD is largely punted
on.
FWIW gdb is the only user of bfd_get_alt_debug_link_info outside of
BFD itself.
I moved the build-id logic out of elfread.c and into a new file.
This seemed cleanest to me.
Writing a test case was a bit of a pain. I added a couple new
features to the DWARF assembler to handle this.
Built and regtested on x86-64 Fedora 18.
* bfd-in2.h: Rebuild.
* opncls.c (bfd_get_alt_debug_link_info): Add buildid_len
parameter. Change type of buildid_out. Update.
(get_alt_debug_link_info_shim): New function.
(bfd_follow_gnu_debuglink): Use it.
* Makefile.in (SFILES): Add build-id.c.
(HFILES_NO_SRCDIR): Add build-id.h.
* build-id.c: New file, largely from elfread.c. Modified
most functions.
* build-id.h: New file.
* dwarf2read.c (dwarf2_get_dwz_file): Update for change to
bfd_get_alt_debug_link_info. Verify dwz file's build-id.
Search for dwz file using build-id.
* elfread.c (build_id_bfd_get, build_id_verify)
(build_id_to_debug_filename, find_separate_debug_file): Remove.
* gdb.dwarf2/dwzbuildid.exp: New file.
* lib/dwarf.exp (Dwarf::_section): Add "flags" and "type"
parameters.
(Dwarf::_defer_output): Change "section" parameter to
"section_spec"; update.
(Dwarf::gnu_debugaltlink, Dwarf::_note, Dwarf::build_id): New
procs.
This fixes dwz.exp on 32-bit targets. It does so by introducing a new
"default" setting for the address size in the DWARF assembler.
Built and regtested on x86-64 Fedora 18.
I also ran the gdb.dwarf2 tests on an x86 machine (gcc45).
* lib/dwarf.exp (cu, tu): Handle addr_size of "default". Change
default addr_size.
* lib/gdb.exp (is_64_target): New gdb_caching_proc.
PR symtab/15391 is a failure with the DW_OP_GNU_implicit_pointer
feature.
I tracked it down to a logic error in read_pieced_value. The code
truncates this_size_bits according to the type size and offset too
early -- it should do it after taking bits_to_skip into account.
This patch fixes the bug.
While testing this, I also tripped across a latent bug because
indirect_pieced_value does not sign-extend where needed. This patch
fixes this bug as well.
Finally, Pedro pointed out that a previous version implemented sign
extension incorrectly. This version introduces a new gdb_sign_extend
function for this. A couple of notes on this function:
* It has the gdb_ prefix to avoid clashes with various libraries that
felt free to avoid proper namespacing. There is a "sign_extend"
function in a Tile GX header, in an SOM-related BFD header (and in
sh64-tdep.c and as a macro in arm-wince-tdep.c, but those are
ours...)
* I looked at all the sign extensions in gdb and didn't see ones that
I felt comfortable converting to use this function; in large part
because I don't have a good way to test the conversion.
Built and regtested on x86-64 Fedora 18. New test cases included;
this required a minor addition to the DWARF assembler. Note that the
DWARF CU made by implptrpiece.exp uses a funny pointer size in order
to show the sign-extension bug on all platforms.
* dwarf2loc.c (read_pieced_value): Truncate this_size_bits
after taking bits_to_skip into account. Sign extend byte_offset.
* utils.h (gdb_sign_extend): Declare.
* utils.c (gdb_sign_extend): New function.
* gdb.dwarf2/implptrpiece.exp: New file.
* gdb.dwarf2/implptrconst.exp (d): New variable.
Print d.
* lib/dwarf2.exp (Dwarf::_location): Handle DW_OP_piece.
Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.