From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 14647 invoked by alias); 7 Jun 2013 14:29:50 -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 14632 invoked by uid 89); 7 Jun 2013 14:29:49 -0000 X-Spam-SWARE-Status: No, score=-7.5 required=5.0 tests=AWL,BAYES_00,KHOP_THREADED,RCVD_IN_HOSTKARMA_W,RCVD_IN_HOSTKARMA_WL,RP_MATCHES_RCVD,SPF_HELO_PASS,SPF_PASS autolearn=ham version=3.3.1 Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.84/v0.84-167-ge50287c) with ESMTP; Fri, 07 Jun 2013 14:29:48 +0000 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r57ETlwQ027835 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 7 Jun 2013 10:29:47 -0400 Received: from Mair.local (vpn-52-128.rdu2.redhat.com [10.10.52.128]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id r57ETj5v008575; Fri, 7 Jun 2013 10:29:46 -0400 Message-ID: <51B1EE59.20004@redhat.com> Date: Fri, 07 Jun 2013 14:29:00 -0000 From: Vladimir Makarov User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:17.0) Gecko/20130509 Thunderbird/17.0.6 MIME-Version: 1.0 To: David Edelsohn CC: GCC Patches Subject: Re: patch to fix PR57468 References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2013-06/txt/msg00404.txt.bz2 On 13-06-06 9:22 PM, David Edelsohn wrote: >> The patch actually restore the LRA behaviour for x86/x86-64 before rev. 199298. The revision was added for PPC SDmode value correct generation. So it is really needed for PPC64 and badly hurts x86/x86-64 performance (by doing secondary memory reloads when one pseudo is spilled). > Should the solution for PPC64 be further limited, even on > PPC64? Is this going to hurt more normal spilling code on PPC64 that > does not have the strange restrictions of SDmode? > > No, it does not hurt ppc performance. In ppc case, it works the same way as reload does (and only for SDmode values). I also found LRA generates a better code for SDmode than reload. I did not figure out why reload pass uses secondary memory when one pseudo is spilled for ppc and does not use this for x86/x86-64 although both targets report necessity of secondary memory in case when one pseudo is spilled. It requires a lot of time but I should probably still do this. I hope that Mike checks performance of LRA as I have no hardware to do this. If he finds any performance degradation, I look at it.