From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 24828 invoked by alias); 26 Jun 2014 06:43:53 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 24810 invoked by uid 89); 26 Jun 2014 06:43:52 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.2 X-HELO: mail-wi0-f178.google.com Received: from mail-wi0-f178.google.com (HELO mail-wi0-f178.google.com) (209.85.212.178) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-SHA encrypted) ESMTPS; Thu, 26 Jun 2014 06:43:51 +0000 Received: by mail-wi0-f178.google.com with SMTP id n15so403925wiw.5 for ; Wed, 25 Jun 2014 23:43:48 -0700 (PDT) X-Received: by 10.180.10.98 with SMTP id h2mr1876503wib.29.1403765028451; Wed, 25 Jun 2014 23:43:48 -0700 (PDT) Received: from android-4c5a376a18c0e957.fritz.box (p54958BFD.dip0.t-ipconnect.de. [84.149.139.253]) by mx.google.com with ESMTPSA id wi9sm12359015wjc.23.2014.06.25.23.43.47 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 25 Jun 2014 23:43:47 -0700 (PDT) User-Agent: K-9 Mail for Android In-Reply-To: <20140625220321.GA18164@virgil.suse> References: <20140620114418.GB24436@virgil.suse> <20140624201933.GB32150@virgil.suse> <53AB3BB7.7020603@redhat.com> <20140625220321.GA18164@virgil.suse> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Subject: Re: [PATCH] Change default for --param allow-...-data-races to off From: Richard Biener Date: Thu, 26 Jun 2014 06:43:00 -0000 To: Martin Jambor ,Jeff Law CC: Bernd Edlinger ,"gcc-patches@gcc.gnu.org" Message-ID: <4f368295-ca87-454f-8300-212ec86de48d@email.android.com> X-IsSubscribed: yes X-SW-Source: 2014-06/txt/msg02092.txt.bz2 On June 26, 2014 12:03:21 AM CEST, Martin Jambor wrote: >Hi, > >On Wed, Jun 25, 2014 at 03:14:31PM -0600, Jeff Law wrote: >> On 06/24/14 14:19, Martin Jambor wrote: >> >On Mon, Jun 23, 2014 at 03:35:01PM +0200, Bernd Edlinger wrote: >> >>Hi Martin, >> >> >> >>>> >> >>>>Well actually, I am not sure if we ever wanted to have a race >condition here. >> >>>>Have you seen any impact of --param allow-store-data-races on any >benchmark? >> >>> >> >>>It's trivially to write one. The only pass that checks the param >is >> >>>tree loop invariant motion and it does that when it applies >store-motion. >> >>>Register pressure increase is increased by a factor of two. >> >>> >> >>>So I'd agree that we might want to disable this again for -Ofast. >> >>> >> >>>As nothing tests for the PACKED variants nor for the LOAD variant >> >>>I'd rather remove those. Claiming we don't create races for those >> >>>when you disable it via the param is simply not true. >> >>> >> >>>Thanks, >> >>>Richard. >> >>> >> >> >> >>OK, please go ahead with your patch. >> > >> >Perhaps not unsurprisingly, the patch is very similar. Bootstrapped >> >and tested on x86_64-linux. OK for trunk? >> > >> >Thanks, >> > >> >Martin >> > >> > >> >2014-06-24 Martin Jambor >> > >> > * params.def (PARAM_ALLOW_LOAD_DATA_RACES) >> > (PARAM_ALLOW_PACKED_LOAD_DATA_RACES) >> > (PARAM_ALLOW_PACKED_STORE_DATA_RACES): Removed. >> > (PARAM_ALLOW_STORE_DATA_RACES): Set default to zero. >> > * opts.c (default_options_optimization): Set >> > PARAM_ALLOW_STORE_DATA_RACES to one at -Ofast. >> > * doc/invoke.texi (allow-load-data-races) >> > (allow-packed-load-data-races, allow-packed-store-data-races): >> > Removed. >> > (allow-store-data-races): Document the new default. >> > >> >testsuite/ >> > * g++.dg/simulate-thread/bitfields-2.C: Remove >allow-load-data-races >> > parameter. >> > * g++.dg/simulate-thread/bitfields.C: Likewise. >> > * gcc.dg/simulate-thread/strict-align-global.c: Remove >> > allow-packed-store-data-races parameter. >> > * gcc.dg/simulate-thread/subfields.c: Likewise. >> > * gcc.dg/tree-ssa/20050314-1.c: Set parameter >allow-store-data-races >> > to one. >> Don't we want to deprecate, not remove the dead options? >> > >Is there a mechanism for deprecating parameters (I could not quickly >find any) or do you mean to leave them there and only document them as >deprecated? > >I am not really concerned how we deal with the unused parameters, >removing or any form of deprecating is fine with me. --params are not a stable interface, so we can just remove those. Of course this would be the opportunity to introduce a real option for this task and leave the param as an implementation detail. Richard. >Thanks, > >Martin