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[binutils-gdb] Avoid expensive complaint calls when complaints are disabled
- From: sergiodj+buildbot at sergiodj dot net
- To: gdb-testers at sourceware dot org
- Date: Wed, 08 Nov 2017 18:54:16 -0500
- Subject: [binutils-gdb] Avoid expensive complaint calls when complaints are disabled
- Authentication-results: sourceware.org; auth=none
*** TEST RESULTS FOR COMMIT 62d7ae92341b53ef10b709464edca759d6738500 ***
Author: Pedro Alves <palves@redhat.com>
Branch: master
Commit: 62d7ae92341b53ef10b709464edca759d6738500
Avoid expensive complaint calls when complaints are disabled
Running perf on "gdb -nx -readnow -batch gdb", I'm seeing a lot of
time (24%.75!) spent in gettext, via complaints. 'perf report -g' shows:
- 86.23% 0.00% gdb gdb [.] gdb_main
- gdb_main
- 85.60% catch_command_errors
symbol_file_add_main_adapter
symbol_file_add_main
symbol_file_add_main_1
symbol_file_add
- symbol_file_add_with_addrs
- 84.31% dw2_expand_all_symtabs
- dw2_instantiate_symtab
- 83.79% dw2_do_instantiate_symtab
- 70.85% process_die
- 41.11% dwarf_decode_macros
- 41.09% dwarf_decode_macro_bytes
- 39.74% dwarf_decode_macro_bytes
>>>>>>>>>>>>>>>>>>>>>>> + 24.75% __dcigettext <<<<<<<
+ 7.37% macro_define_object_internal
+ 3.16% macro_define_function
0.77% splay_tree_insert
+ 0.76% savestring
+ 0.58% free
0.53% read_indirect_string_at_offset_from
0.54% macro_define_object_internal
0.51% macro_start_file
+ 25.57% process_die
+ 4.07% dwarf_decode_lines
+ 4.28% compute_delayed_physnames
+ 3.85% end_symtab_from_static_block
+ 3.38% load_cu
+ 1.29% end_symtab_get_static_block
+ 0.52% do_my_cleanups
+ 1.29% read_symbols
+ 0.54% gdb_init
The problem is that we're always computing the arguments to pass to
complaint, including passing the format strings through gettext, even
when complaints are disabled. As seen above, gettext can be quite
expensive.
Fix this by wrapping complaint in a macro that skips the real
complaint call when complaints are disabled.
This improves "gdb -nx -readnow -batch gdb" from
~11.0s => ~7.8s with -O2 -g3, and
~6.0s => ~5.3s with -O2 -g.
w/ gcc 5.3.1, on x86_64, for me.
gdb/ChangeLog:
2017-11-08 Pedro Alves <palves@redhat.com>
* complaints.c (stop_whining): Make extern.
(complaint): Rename to ...
(complaint_internal): ... this.
* complaints.h (complaint): Rename to ...
(complaint_internal): ... this.
(complaint): Reimplement as macro around complaint_internal.
gdb/testsuite/ChangeLog:
2017-11-08 Pedro Alves <palves@redhat.com>
* gdb.gdb/complaints.exp (test_initial_complaints)
(test_serial_complaints, test_short_complaints): Call
complaint_internal instead of complaint.
- Follow-Ups:
- *** COMPILATION FAILED *** Failures on Ubuntu-AArch32-m32, branch master *** BREAKAGE ***
- *** COMPILATION FAILED *** Failures on Ubuntu-AArch32-native-extended-gdbserver-m32, branch master *** BREAKAGE ***
- *** COMPILATION FAILED *** Failures on Ubuntu-AArch32-native-gdbserver-m32, branch master *** BREAKAGE ***
- Failures on Fedora-s390x-m64, branch master
- *** COMPILATION FAILED *** Failures on Fedora-i686, branch master *** BREAKAGE ***
- Failures on Fedora-x86_64-native-gdbserver-m64, branch master
- Failures on Fedora-x86_64-native-extended-gdbserver-m64, branch master
- Failures on Fedora-x86_64-m32, branch master
- Failures on Fedora-x86_64-native-extended-gdbserver-m32, branch master
- Failures on Fedora-x86_64-cc-with-index, branch master
- Failures on Ubuntu-AArch64-native-gdbserver-m64, branch master
- Failures on Ubuntu-AArch64-m64, branch master