From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 98353 invoked by alias); 12 Jan 2016 13:05:18 -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 98342 invoked by uid 89); 12 Jan 2016 13:05:17 -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_PASS autolearn=ham version=3.3.2 spammy=Hx-languages-length:1107, jane 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; Tue, 12 Jan 2016 13:05:15 +0000 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39876) by fencepost.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1aIydN-0002ZS-BT for gcc-patches@gnu.org; Tue, 12 Jan 2016 08:05:13 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aIydJ-0003Qt-40 for gcc-patches@gnu.org; Tue, 12 Jan 2016 08:05:13 -0500 Received: from mx2.suse.de ([195.135.220.15]:60711) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aIydI-0003OS-OA for gcc-patches@gnu.org; Tue, 12 Jan 2016 08:05:09 -0500 Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 0ADA9AD54; Tue, 12 Jan 2016 13:04:57 +0000 (UTC) Date: Tue, 12 Jan 2016 13:05:00 -0000 From: Richard Biener To: Tom de Vries cc: "gcc-patches@gnu.org" , Sebastian Pop Subject: Re: [PATCH, PR69110] Don't return NULL access_fns in dr_analyze_indices In-Reply-To: <5694F5BA.7030207@mentor.com> Message-ID: References: <5694CF85.1020708@mentor.com> <5694F5BA.7030207@mentor.com> User-Agent: Alpine 2.11 (LSU 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x (no timestamps) [generic] X-Received-From: 195.135.220.15 X-SW-Source: 2016-01/txt/msg00712.txt.bz2 On Tue, 12 Jan 2016, Tom de Vries wrote: > On 12/01/16 12:22, Richard Biener wrote: > > Doesnt' the same issue apply to > > > > > >unsigned int *p; > > > > > > > >static void __attribute__((noinline, noclone)) > > > >foo (void) > > > >{ > > > > unsigned int z; > > > > > > > > for (z = 0; z < N; ++z) > > > > ++(*p); > > > >} > > thus when we have a MEM_REF[p_1]? SCEV will not analyze > > its evolution to a POLYNOMIAL_CHREC and thus access_fns will > > be NULL again. > > > > I didn't manage to trigger this scenario, though I could probably make it > happen by modifying ftree-loop-im to work in one case (the load of the value > of p) but not the other (the *p load and store). > > > I think avoiding a NULL access_fns is ok but it should be done > > unconditionally, not only for the DECL_P case. > > Ok, I'll retest and commit this patch. Please add a comment as well. > Thanks, > - Tom > -- Richard Biener SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nuernberg)