From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 23767 invoked by alias); 25 Feb 2017 00:14:47 -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 23758 invoked by uid 89); 25 Feb 2017 00:14:46 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=willingness, Matt, stabilization, his X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Sat, 25 Feb 2017 00:14:45 +0000 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8593181222; Sat, 25 Feb 2017 00:14:45 +0000 (UTC) Received: from [10.10.120.173] (ovpn-120-173.rdu2.redhat.com [10.10.120.173] (may be forged)) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v1P0Ei0S016227; Fri, 24 Feb 2017 19:14:44 -0500 Subject: Re: [PATCH] PR79584, lra ICE in base_to_reg To: Alan Modra , gcc-patches@gcc.gnu.org, rdsandiford@googlemail.com References: <20170222202522.GK14945@bubble.grove.modra.org> <87r32pltj8.fsf@googlemail.com> <20170223011109.GL14945@bubble.grove.modra.org> <20170223014659.GM14945@bubble.grove.modra.org> <871suoh3jm.fsf@googlemail.com> <20170224050710.GS14945@bubble.grove.modra.org> From: Vladimir Makarov Message-ID: <2be33d02-1a62-3f7d-1229-4df80b868f08@redhat.com> Date: Sat, 25 Feb 2017 07:42:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.7.0 MIME-Version: 1.0 In-Reply-To: <20170224050710.GS14945@bubble.grove.modra.org> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes X-SW-Source: 2017-02/txt/msg01530.txt.bz2 On 02/24/2017 12:07 AM, Alan Modra wrote: > I'm going to wait for Vlad's opinion. I've written a couple of > replies and erased them, since I figure whatever I have to say doesn't > carry much weight. > I would prefer not to touch simplify_subreg_operand, especially a code related to subreg of mem. Changes of the code usually result in a long time stabilization work. The change might result in LRA cycling (I remember it happened before exactly for ppc SD memory handling). It is dangerous when we are closer to the release. I hope more work on clearing the simplify_subreg_operand code will be done for GCC-8 (at least Matt Fortune expressed his willingness to do this). Although it is better to avoid a wrong RTL code creation earlier, LRA already can create a wrong code during its work for a long period of time. It already happens for some cases. So please commit your patch, Allan. But before doing it also please check that the patch does not creates problems on x86-64 bootstrap and GCC tests. Thank you.