This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [SFN+LVU+IEPM v4 9/9] [IEPM] Introduce inline entry point markers
- From: Jeff Law <law at redhat dot com>
- To: Alexandre Oliva <aoliva at redhat dot com>, Szabolcs Nagy <szabolcs dot nagy at arm dot com>, Uros Bizjak <ubizjak at gmail dot com>
- Cc: Rainer Orth <ro at CeBiTec dot Uni-Bielefeld dot DE>, nd at arm dot com, Jakub Jelinek <jakub at redhat dot com>, Alan Modra <amodra at gmail dot com>, Jason Merrill <jason at redhat dot com>, Richard Biener <richard dot guenther at gmail dot com>, GCC Patches <gcc-patches at gcc dot gnu dot org>
- Date: Wed, 7 Mar 2018 12:43:21 -0700
- Subject: Re: [SFN+LVU+IEPM v4 9/9] [IEPM] Introduce inline entry point markers
- Authentication-results: sourceware.org; auth=none
- References: <orlgjec1b5.fsf_-_@lxoliva.fsfla.org> <20171110023448.28164-9-aoliva@redhat.com> <or7etsvep6.fsf@lxoliva.fsfla.org> <20180124171232.GG2063@tucnak> <orh8r94s88.fsf@lxoliva.fsfla.org> <orlgg2etl4.fsf@lxoliva.fsfla.org> <20180209035334.GF3846@bubble.grove.modra.org> <6e28e34e-681d-bebb-d815-569eee148de5@redhat.com> <or1shtlvx6.fsf@lxoliva.fsfla.org> <20180209211000.GN5867@tucnak> <orzi4hek6z.fsf@lxoliva.fsfla.org> <oreflqeikg.fsf@lxoliva.fsfla.org> <ortvulroml.fsf@lxoliva.fsfla.org> <90d68594-5d0f-b3c5-fc34-8d33c7fcdf04@arm.com> <ormv02odoi.fsf@lxoliva.fsfla.org>
On 02/21/2018 03:11 AM, Alexandre Oliva wrote:
> On Feb 15, 2018, Szabolcs Nagy <szabolcs.nagy@arm.com> wrote:
>
>> i see assembler slow downs with these location view patches
>> i opened https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84408
>
>
> [LVU] reset view at function entry, omit views at line zero
>
> Location views might be associated with locations that lack line
> number information (line number zero), but since we omit .loc
> directives that would have been issued with line number zero, we also
> omit the symbolic view numbers that would have been issued at such
> points.
>
> Resetting views at function entry points address some of these issues,
> and alleviate the huge chains of symbolic views that have burdened
> assemblers since we disabled -ginternal-reset-location-views by
> default, but other problems of undefined views remain when it's not
> the whole function that lacks line number info, just parts of it.
>
> So, when we encounter a request to output a view that may have been
> referenced, but we decide to omit the .loc because the line is zero,
> we will now omit the view as well, i.e., we will internally regard
> that view as zero-numbered.
>
> Regstrapped on x86_64-linux-gnu and i686-linux-gnu. Ok to install?
>
> Uros, could you please confirm whether this fixes the 84404 go problem
> you reported on alpha? I'm guessing it's the same issue. TIA,
>
> for gcc/ChangeLog
>
> PR debug/84404
> PR debug/84408
> * dwarf2out.c (struct dw_line_info_table): Update comments for
> view == -1.
> (FORCE_RESET_NEXT_VIEW): New.
> (FORCE_RESETTING_VIEW_P): New.
> (RESETTING_VIEW_P): Check for -1 too.
> (ZERO_VIEW_P): Likewise.
> (new_line_info_table): Force-reset next view.
> (dwarf2out_begin_function): Likewise.
> (dwarf2out_source_line): Simplify zero_view_p initialization.
> Test FORCE_RESETTING_VIEW_P and RESETTING_VIEW_P instead of
> view directly. Omit view when omitting .loc at line 0.
>
> for gcc/testsuite/ChangeLog
>
> PR debug/84404
> PR debug/84408
> * gcc.dg/graphite/pr84404.c: New.
OK.
jeff