From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 105858 invoked by alias); 16 Jul 2015 11:20:08 -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 105846 invoked by uid 89); 16 Jul 2015 11:20:07 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.6 required=5.0 tests=AWL,BAYES_00,RP_MATCHES_RCVD,SPF_PASS autolearn=ham version=3.3.2 X-HELO: fencepost.gnu.org Received: from fencepost.gnu.org (HELO fencepost.gnu.org) (208.118.235.10) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-SHA encrypted) ESMTPS; Thu, 16 Jul 2015 11:20:06 +0000 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59240) by fencepost.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1ZFhCu-0007Ph-50 for gcc-patches@gnu.org; Thu, 16 Jul 2015 07:20:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZFhCq-0003pc-FY for gcc-patches@gnu.org; Thu, 16 Jul 2015 07:20:03 -0400 Received: from relay1.mentorg.com ([192.94.38.131]:42291) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZFhCq-0003pG-Ac for gcc-patches@gnu.org; Thu, 16 Jul 2015 07:20:00 -0400 Received: from nat-ies.mentorg.com ([192.94.31.2] helo=SVR-IES-FEM-02.mgc.mentorg.com) by relay1.mentorg.com with esmtp id 1ZFhCo-0005fU-ED from Tom_deVries@mentor.com ; Thu, 16 Jul 2015 04:19:58 -0700 Received: from [127.0.0.1] (137.202.0.76) by SVR-IES-FEM-02.mgc.mentorg.com (137.202.0.106) with Microsoft SMTP Server id 14.3.224.2; Thu, 16 Jul 2015 12:19:57 +0100 Message-ID: <55A7935A.60401@mentor.com> Date: Thu, 16 Jul 2015 11:41:00 -0000 From: Tom de Vries User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Richard Biener , Thomas Schwinge CC: "gcc-patches@gnu.org" Subject: Re: [RFC, PR66873] Use graphite for parloops References: <55A6C1DF.1050108@mentor.com> <87fv4owgjy.fsf@kepler.schwinge.homeip.net> In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit X-detected-operating-system: by eggs.gnu.org: Windows NT kernel [generic] [fuzzy] X-Received-From: 192.94.38.131 X-SW-Source: 2015-07/txt/msg01388.txt.bz2 On 16/07/15 12:23, Richard Biener wrote: > On Thu, Jul 16, 2015 at 12:19 PM, Thomas Schwinge > wrote: >> Hi Tom! >> >> On Thu, 16 Jul 2015 10:46:00 +0200, Richard Biener wrote: >>> On Wed, Jul 15, 2015 at 10:26 PM, Tom de Vries wrote: >>>> I tried to parallelize this fortran test-case (based on autopar/outer-1.c), >>>> [...] >> >>>> So I wondered, why not always use the graphite dependency analysis in >>>> parloops. (Of course you could use -floop-parallelize-all, but that also >>>> changes the heuristic). So I wrote a patch for parloops to use graphite >>>> dependency analysis by default (so without -floop-parallelize-all), but >>>> while testing found out that all the reduction test-cases started failing >>>> because the modifications graphite makes to the code messes up the parloops >>>> reduction analysis. >>>> >>>> Then I came up with this patch, which: >>>> - first runs a parloops pass, restricted to reduction loops only, >>>> - then runs graphite dependency analysis >>>> - followed by a normal parloops pass run. >>>> >>>> This way, we get to both: >>>> - compile the reduction testcases as before, and >>>> - profit from the better graphite dependency analysis otherwise. >> >>> graphite dependence analysis is too slow to be enabled unconditionally. >>> (read: hours in some simple cases - see bugzilla) >> >> Haha, "cool"! ;-) >> >> Maybe it is still reasonable to use graphite to analyze the code inside >> OpenACC kernels regions -- maybe such code can reasonably be expected to >> not have the properties that make its analysis lengthy? So, Tom, could >> you please identify and check such PRs, to get an understanding of what >> these properties are? > > Like the one in PR62113 or 53852 or 59121. PR62113 and PR59121 do not reproduce for me on trunk. PR53852 does reproduce for me (to the point that I had to reset my laptop). Thanks, - Tom