Now that defs.h, server.h and common-defs.h are included via the
`-include` option, it is no longer necessary for source files to include
them. Remove all the inclusions of these files I could find. Update
the generation scripts where relevant.
Change-Id: Ia026cff269c1b7ae7386dd3619bc9bb6a5332837
Approved-By: Pedro Alves <pedro@palves.net>
This commit is the result of the following actions:
- Running gdb/copyright.py to update all of the copyright headers to
include 2024,
- Manually updating a few files the copyright.py script told me to
update, these files had copyright headers embedded within the
file,
- Regenerating gdbsupport/Makefile.in to refresh it's copyright
date,
- Using grep to find other files that still mentioned 2023. If
these files were updated last year from 2022 to 2023 then I've
updated them this year to 2024.
I'm sure I've probably missed some dates. Feel free to fix them up as
you spot them.
Fortran provides additional entry points for subroutines and functions.
These entry points may use only a subset (or a different set) of the
parameters of the original subroutine. The entry points may be described
via the DWARF tag DW_TAG_entry_point.
This commit adds support for parsing the DW_TAG_entry_point DWARF tag.
Currently, between ifx/ifort/gfortran, only ifort is actually emitting
this tag. Both, ifx and gfortran use the DW_TAG_subprogram tag as
workaround/alternative. Thus, this patch really only adds more ifort
support. Even so, some of the attached tests still fail for ifort, due
to some wrong line info generated for the entry points in ifort.
After this patch it is possible to set a breakpoint in gdb with the
ifort compiled example at the entry points 'foo' and 'foobar', which was not
possible before.
As gcc and ifx do not emit the tag I also added a test to gdb.dwarf2
which uses some underlying c compiled code and adds some Fortran style DWARF
to it emitting the DW_TAG_entry_point. Before this patch it was not
possible to actually define breakpoint at the entry point tags.
For gfortran there actually exists a bug on bugzilla, asking for the use
of DW_TAG_entry_point over DW_TAG_subprogram:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=37134
This patch was originally posted here
https://sourceware.org/legacy-ml/gdb-patches/2017-07/msg00317.html
but its review/pinging got lost after a while. I reworked it to fit the
current GDB.
Co-authored-by: Bernhard Heckel <bernhard.heckel@intel.com>
Co-authored-by: Tim Wiederhake <tim.wiederhake@intel.com>
Approved-by: Tom Tromey <tom@tromey.com>
Consider the test-case:
...
$ cat main.c
int main (void) { return 0; }
$ cat static-optimized-out.c
static int aaa;
...
compiled like this:
...
$ gcc-12 static-optimized-out.c main.c -g -O2 -flto
...
There's a difference in behaviour depending on symtab expansion state:
...
$ gdb -q -batch a.out -ex "print aaa"
No symbol "aaa" in current context.
$ gdb -q -batch a.out -ex "maint expand-symtab" -ex "print aaa"
$1 = <optimized out>
...
The reason for the difference is that the optimized out variable aaa:
...
<1><104>: Abbrev Number: 2 (DW_TAG_variable)
<105> DW_AT_name : aaa
<109> DW_AT_decl_file : 1
<10a> DW_AT_decl_line : 18
<10b> DW_AT_decl_column : 12
<10c> DW_AT_type : <0x110>
...
is not added to the cooked index because of this clause in abbrev_table::read:
...
else if (!has_location && !has_specification_or_origin && !has_external
&& cur_abbrev->tag == DW_TAG_variable)
cur_abbrev->interesting = false;
...
Fix this inconsistency by making sure that the optimized out variable is added
to the cooked index.
Regression tested on x86_64-linux.
Add two test-cases, a C test-case gdb.opt/static-optimized-out.exp and a dwarf
assembly test-case gdb.dwarf2/static-optimized-out.exp.
Tested gdb.opt/static-optimized-out.exp with gcc-8 to gcc-12, for which we now
consistently get:
...
(gdb) print aaa^M
$1 = <optimized out>^M
...
and with gcc 7.5.0 and clang 13.0.1, for which we still consistently get:
...
(gdb) print aaa^M
No symbol "aaa" in current context.^M
...
due to missing debug info for the variable.
PR symtab/30656
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30656
Approved-By: Tom Tromey <tom@tromey.com>
This commit is the result of running the gdb/copyright.py script,
which automated the update of the copyright year range for all
source files managed by the GDB project to be updated to include
year 2023.
Pedro pointed out that gdb-add-index is much slower with the new DWARF
indexer. He also noticed that, in some cases, the generated
.gdb_index would have the wrong fully-qualified name for a method.
I tracked this down to a bug in the indexer. If a type could have
methods but was marked as a declaration, the indexer was ignoring it.
However, this meant that the internal map to find the qualified name
was not updated for this container.
The new DIE scanner works more or less along the lines indicated by
the text for the .debug_names section, disregarding the bugs in the
specification.
While working on this, I noticed that whether a DIE is interesting is
a static property of the DIE's abbrev. It also turns out that many
abbrevs imply a static size for the DIE data, and additionally that
for many abbrevs, the sibling offset is stored at a constant offset
from the start of the DIE.
This patch changes the abbrev reader to analyze each abbrev and stash
the results on the abbrev. These combine to speed up the new indexer.
If the "interesting" flag is false, GDB knows to skip the DIE
immediately. If the sibling offset is statically known, skipping can
be done without reading any attributes; and in some other cases, the
DIE can be skipped using simple arithmetic.
The replacement for the DWARF psymbol reader works in a somewhat
different way. The current reader reads and stores all the DIEs that
might be interesting. Then, if it is missing a DIE, it re-scans the
CU and reads them all. This approach is used for both intra- and
inter-CU references.
I instrumented the partial DIE hash to see how frequently it was used:
[ 0] -> 1538165
[ 1] -> 4912
[ 2] -> 96102
[ 3] -> 175
[ 4] -> 244
That is, most DIEs are never used, and some are looked up twice -- but
this is just an artifact of the implementation of
partial_die_info::fixup, which may do two lookups.
Based on this, the new implementation doesn't try to store any DIEs,
but instead just re-scans them on demand. In order to do this,
though, it is convenient to have a cache of DWARF abbrevs. This way,
if a second CU is needed to resolve an inter-CU reference, the abbrevs
for that CU need only be computed a single time.
This commit brings all the changes made by running gdb/copyright.py
as per GDB's Start of New Year Procedure.
For the avoidance of doubt, all changes in this commits were
performed by the script.
abbrev_table::read has a workaround for Irix 6. The last release of
Irix was in 2006, and (according to Wikipedia) hardware produced after
2007 cannot run Irix. I think this workaround can safely be retired.
gdb/ChangeLog
2021-03-13 Tom Tromey <tom@tromey.com>
* dwarf2/abbrev.c (abbrev_table::read): Remove Irix 6 workaround.
Currently, and abbrev_info points to a separately allocated array of
attr_abbrev objects. This array is constructed in a temporary vector,
then copied to the abbrev table's obstack.
This patch changes abbrev_info to use the struct hack to store the
objects directly, and changes abbrev_table::read to avoid an extra
copy when allocating, using the "growing objects" capability of
obstacks.
This saves a bit of space, and also perhaps a little time.
2021-03-06 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_attribute): Make 'abbrev' const.
* dwarf2/abbrev.c (abbrev_table::alloc_abbrev): Remove.
(abbrev_table::read): Update.
* dwarf2/abbrev.h (struct attr_abbrev): Move earlier.
(struct abbrev_info): Reformat.
<attrs>: Now an array.
(struct abbrev_table) <alloc_abbrev>: Remove.
This commits the result of running gdb/copyright.py as per our Start
of New Year procedure...
gdb/ChangeLog
Update copyright year range in copyright header of all GDB files.
In a longer series that I am working on, I needed to remove the
objfile parameter from abbrev_table::read. It seemed to me that this
was a simple and relatively harmless patch, so I'm sending it now.
gdb/ChangeLog
2020-11-05 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_cutu_die_from_dwo)
(cutu_reader::cutu_reader, cutu_reader::cutu_reader)
(build_type_psymtabs_1): Update.
* dwarf2/abbrev.h (struct abbrev_table): Remove objfile
parameter.
* dwarf2/abbrev.c (abbrev_table::read): Remove objfile parameter.
Don't read section. Add assert.
Profiling showed that calls to abbrev_table::lookup_abbrev were "too
visible". As these are just forwarding calls to the hash table, this
patch inlines the lookup. Also, htab_find_with_hash is used, avoiding
another call.
The run previous to this had times of (see the first patch in the
series for an explanation):
gdb 1.69
libxul 2.02
Ada 2.52
This patch improves the times to:
gdb 1.64
libxul 1.99
Ada 2.47
gdb/ChangeLog
2020-05-27 Tom Tromey <tromey@adacore.com>
* dwarf2/abbrev.h (struct abbrev_table) <lookup_abbrev>: Inline.
Use htab_find_with_hash.
<add_abbrev>: Remove "abbrev_number" parameter.
* dwarf2/abbrev.c (abbrev_table::add_abbrev): Remove
"abbrev_number" parameter. Use htab_find_slot_with_hash.
(hash_abbrev): Add comment.
(abbrev_table::lookup_abbrev): Move to header file.
(abbrev_table::read): Update.
I compiled gdb with -fsanitize=undefined and ran the test suite.
A couple of reports came from passing NULL to memcpy, e.g.:
[...]btrace-common.cc:176:13: runtime error: null pointer passed as argument 2, which is declared to never be null
While it would be better to fix this in the standard, in the meantime
it seems easy to avoid this error.
gdb/ChangeLog
2020-03-31 Tom Tromey <tromey@adacore.com>
* dwarf2/abbrev.c (abbrev_table::read): Conditionally call
memcpy.
gdbsupport/ChangeLog
2020-03-31 Tom Tromey <tromey@adacore.com>
* btrace-common.cc (btrace_data_append): Conditionally call
memcpy.
abbrev_table::read increments cur_abbrev->num_attrs in the inner loop,
but there's no need to do this, as the information is already stored
in the temporary vector.
2020-02-08 Tom Tromey <tom@tromey.com>
* dwarf2/abbrev.c (abbrev_table::read): Simplify.
Change-Id: I765f12850ffa1c6066e884bb22c94468d1abdba4
This changes abbrev_table to use an htab_up rather than an ad hoc,
bucket-based hash table.
2020-02-08 Tom Tromey <tom@tromey.com>
* dwarf2/abbrev.c (abbrev_table): Move constructor from header.
Rewrite.
(abbrev_table::add_abbrev, abbrev_table::lookup_abbrev): Rewrite.
* dwarf2/abbrev.h (struct abbrev_info) <next>: Remove.
(abbrev_table::abbrev_table): No longer inline.
(ABBREV_HASH_SIZE): Remove.
(abbrev_table::m_abbrevs): Now an htab_up.
Change-Id: Icbaa8e49501f9c43218d6a81a7e8c4d3a77d65dc
This cleans up the DWARF abbrev_table API a bit, primarily by making
various methods and members private.
2020-02-08 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_cutu_die_from_dwo): Update.
(cutu_reader): Update.
(build_type_psymtabs_1): Update.
* dwarf2/abbrev.c (abbrev_table::read): Rename.
(abbrev_table::alloc_abbrev): Update.
* dwarf2/abbrev.h (abbrev_table_up): Move earlier.
(abbrev_table::read): New static method, renamed from
abbrev_table_read_table.
(abbrev_table::alloc_abbrev)
(abbrev_table::add_abbrev): Now private.
(abbrev_table::abbrev_table): Now private.
(abbrev_table::m_abbrev_obstack): Now private. Rename.
Change-Id: I320dca83b799f672909ae66f73b7aca266adbaf9
This moves the abbrev table code out of dwarf2read.c and into new
files dwarf2/abbrev.[ch].
gdb/ChangeLog
2020-02-08 Tom Tromey <tom@tromey.com>
* dwarf2read.c (abbrev_table_up, struct abbrev_info)
(struct attr_abbrev, ABBREV_HASH_SIZE, struct abbrev_table):
Move.
(read_cutu_die_from_dwo, build_type_psymtabs_1): Update.
(abbrev_table::alloc_abbrev, abbrev_table::add_abbrev)
(abbrev_table::lookup_abbrev, abbrev_table_read_table): Move to
abbrev.c.
* dwarf2/abbrev.h: New file.
* dwarf2/abbrev.c: New file, from dwarf2read.c.
* Makefile.in (COMMON_SFILES): Add dwarf2/abbrev.c.
Change-Id: I87911bc5297de4407587ca849fef8e8d19136c30
