[Bug c++/58575] New: gcc should compile firefox code faster.

[Bug c++/58575] New: gcc should compile firefox code faster.

[tsaunders at mozilla dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58575

            Bug ID: 58575
           Summary: gcc should compile firefox code faster.
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: tsaunders at mozilla dot com
                CC: hubicka at ucw dot cz

Its ceretainly possible given
https://blog.mozilla.org/nnethercote/2013/09/12/bleg-for-a-new-machine-2/ (I'm
not sure what versions njn is using but probably doesn't matter too much).
I rofiled build a build of content/ in the firefox tree for a --enable-optimize
--disable-debug build you can see the data I gathered at
http://people.mozilla.org/~tsaunders/gcc-perf.data .  The two things that came
up high in profiles were C++ parsing stuff and memory allocation.  I suppose
there isn't too much to be done about the memory allocation issue in the short
term, but I wonder if there's changes to the parser that would help at least
some.

[Bug c++/58575] gcc should compile firefox code faster.

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58575

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |DUPLICATE

--- Comment #1 from Paolo Carlini <paolo.carlini at oracle dot com> ---
I'm going to resolve this as duplicate of PR24208. We have got already a number
of more specific bug reports about either memory use, performance, etc. If you
have something *specific* to report please open a *specific* bug.

*** This bug has been marked as a duplicate of bug 24208 ***

[Bug c++/58575] gcc should compile firefox code faster.

[manu at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58575

Manuel López-Ibáñez <manu at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |manu at gcc dot gnu.org

--- Comment #2 from Manuel López-Ibáñez <manu at gcc dot gnu.org> ---
That GCC could be much faster is well-known but how to make it so is less clear
and there is simply not enough people to do the work required. Currently there
is as many people working just on Clang than on the whole GCC (including all
languages, middle-end and backends).

Dimitrios Apostolou did some nice work on benchmarking, but his actual patches
did not bring impressive improvements:

http://gcc.gnu.org/wiki/OptimisingGCC

I don't know how much of this work ended up in GCC (if any).

There are many ideas on what could speed-up C++ parsing:

http://gcc.gnu.org/wiki/Speedup_areas#C.2B-.2B-_improvements

BTW, reducing memory allocation (or using smarter data structures) is likely to
bring significant improvements:

http://gcc.gnu.org/wiki/Speedup_areas#Some_general_thoughts_on_memory_usage

But at the end, someone needs to come up with very detailed benchmark data to
identify the real compile-time hogs and patches to address them.
>From gcc-bugs-return-430956-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Wed Oct 02 10:44:28 2013
Return-Path: <gcc-bugs-return-430956-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Delivered-To: listarch-gcc-bugs@gcc.gnu.org
Received: (qmail 736 invoked by alias); 2 Oct 2013 10:44:28 -0000
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
Delivered-To: mailing list gcc-bugs@gcc.gnu.org
Received: (qmail 687 invoked by uid 55); 2 Oct 2013 10:44:26 -0000
From: "paolo at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/58565] [c++11] ICE with label in statement expression
Date: Wed, 02 Oct 2013 10:44:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: c++
X-Bugzilla-Version: 4.9.0
X-Bugzilla-Keywords: ice-on-invalid-code
X-Bugzilla-Severity: normal
X-Bugzilla-Who: paolo at gcc dot gnu.org
X-Bugzilla-Status: ASSIGNED
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: paolo.carlini at oracle dot com
X-Bugzilla-Target-Milestone: 4.9.0
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields:
Message-ID: <bug-58565-4-8kRoLRqq6f@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-58565-4@http.gcc.gnu.org/bugzilla/>
References: <bug-58565-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-SW-Source: 2013-10/txt/msg00100.txt.bz2
Content-length: 683

http://gcc.gnu.org/bugzilla/show_bug.cgi?idX565

--- Comment #3 from paolo at gcc dot gnu.org <paolo at gcc dot gnu.org> ---
Author: paolo
Date: Wed Oct  2 10:44:23 2013
New Revision: 203109

URL: http://gcc.gnu.org/viewcvs?rev 3109&root=gcc&view=rev
Log:
/cp
2013-10-02  Paolo Carlini  <paolo.carlini@oracle.com>

    PR c++/58565
    * semantics.c (potential_constant_expression_1): Handle LABEL_EXPR.

/testsuite
2013-10-02  Paolo Carlini  <paolo.carlini@oracle.com>

    PR c++/58565
    * g++.dg/parse/crash64.C: New.

Added:
    trunk/gcc/testsuite/g++.dg/parse/crash64.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/semantics.c
    trunk/gcc/testsuite/ChangeLog