From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Alan Mackenzie Newsgroups: gmane.emacs.bugs Subject: bug#23476: Slowdown in C Mode fontification Date: Tue, 10 May 2016 19:00:04 +0000 Message-ID: <20160510190004.GC1923@acm.fritz.box> References: <83lh3lelw1.fsf@gnu.org> <83k2j5ekdc.fsf@gnu.org> <20160507204022.GE3660@acm.fritz.box> <83inyoeek8.fsf@gnu.org> <20160509110713.GA5316@acm.fritz.box> <83shxrcgxz.fsf@gnu.org> <20160509182206.GC5316@acm.fritz.box> <83eg9bcai5.fsf@gnu.org> <20160510075132.GA1923@acm.fritz.box> <8337ppdhmb.fsf@gnu.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1462906890 1035 80.91.229.3 (10 May 2016 19:01:30 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 10 May 2016 19:01:30 +0000 (UTC) Cc: 23476@debbugs.gnu.org To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Tue May 10 21:01:18 2016 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1b0CuD-0007E5-KK for geb-bug-gnu-emacs@m.gmane.org; Tue, 10 May 2016 21:01:17 +0200 Original-Received: from localhost ([::1]:48270 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b0CuC-00020N-Sn for geb-bug-gnu-emacs@m.gmane.org; Tue, 10 May 2016 15:01:16 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:51441) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b0Cu3-0001gF-8l for bug-gnu-emacs@gnu.org; Tue, 10 May 2016 15:01:12 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1b0Cty-0002bj-Nx for bug-gnu-emacs@gnu.org; Tue, 10 May 2016 15:01:06 -0400 Original-Received: from debbugs.gnu.org ([208.118.235.43]:33878) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b0Cty-0002bf-KP for bug-gnu-emacs@gnu.org; Tue, 10 May 2016 15:01:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1b0Cty-0005o1-An for bug-gnu-emacs@gnu.org; Tue, 10 May 2016 15:01:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Alan Mackenzie Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Tue, 10 May 2016 19:01:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 23476 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 23476-submit@debbugs.gnu.org id=B23476.146290681222254 (code B ref 23476); Tue, 10 May 2016 19:01:02 +0000 Original-Received: (at 23476) by debbugs.gnu.org; 10 May 2016 19:00:12 +0000 Original-Received: from localhost ([127.0.0.1]:46215 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1b0CtA-0005ms-FV for submit@debbugs.gnu.org; Tue, 10 May 2016 15:00:12 -0400 Original-Received: from mail.muc.de ([193.149.48.3]:47341) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1b0Ct8-0005mg-BC for 23476@debbugs.gnu.org; Tue, 10 May 2016 15:00:11 -0400 Original-Received: (qmail 55010 invoked by uid 3782); 10 May 2016 19:00:05 -0000 Original-Received: from acm.muc.de (p548C6597.dip0.t-ipconnect.de [84.140.101.151]) by colin.muc.de (tmda-ofmipd) with ESMTP; Tue, 10 May 2016 21:00:04 +0200 Original-Received: (qmail 11612 invoked by uid 1000); 10 May 2016 19:00:04 -0000 Content-Disposition: inline In-Reply-To: <8337ppdhmb.fsf@gnu.org> User-Agent: Mutt/1.5.24 (2015-08-30) X-Delivery-Agent: TMDA/1.1.12 (Macallan) X-Primary-Address: acm@muc.de X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 208.118.235.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.org gmane.emacs.bugs:118078 Archived-At: Hello, Eli. On Tue, May 10, 2016 at 07:04:28PM +0300, Eli Zaretskii wrote: > > Date: Tue, 10 May 2016 07:51:32 +0000 > > Cc: 23476@debbugs.gnu.org, Glenn Morris > > From: Alan Mackenzie > > > Btw, I noticed that CC Mode is quite a bit slower on master than it is > > > on emacs-25 (try searching for "IF_LINT" in xdisp.c), is that related > > > to these changes in any way? > > Whoops! No, this slowdown is caused by commit > > 89d1776b81ab552192ee41f13ce84ff86bda4556 on 2016-04-25, a fix for bug > > #7918. The bug was the spurious fontification of something like "for (; > > a * b;)". > > I'll see if I can find a better fix; if not, it would probably be best to > > remove the commit and leave the bug unfixed. > Since this is only on master (right?), there's no rush to revert the > commit, perhaps you or someone else will come up with a solution that > doesn't bring back bug #7918. I've reverted it. I'm thinking of Martin, who doesn't have a fast machine, and it's annoyingly slow even for me on my machine. In fact the slowdown in fontification is approximately a factor of 3. I've now got some idea how to fix this, and it will be radically different from the reverted commit, not a variation on it. > Thanks. -- Alan Mackenzie (Nuremberg, Germany).