From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 28093 invoked by alias); 20 Feb 2017 13:59:01 -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 28007 invoked by uid 89); 20 Feb 2017 13:58:58 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-11.9 required=5.0 tests=BAYES_00,GIT_PATCH_2,GIT_PATCH_3,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=Hx-languages-length:906 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; Mon, 20 Feb 2017 13:58:57 +0000 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) (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 484F63D953; Mon, 20 Feb 2017 13:58:57 +0000 (UTC) Received: from localhost.localdomain (ovpn-117-151.ams2.redhat.com [10.36.117.151]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v1KDwuDB030197; Mon, 20 Feb 2017 08:58:56 -0500 Subject: Re: fwprop fix for PR79405 To: Richard Biener References: <328a765e-5466-9740-d545-c1a620805ef9@redhat.com> Cc: GCC Patches From: Bernd Schmidt Message-ID: <7d36bb9f-8dfa-855a-7c98-02014469fd89@redhat.com> Date: Mon, 20 Feb 2017 14:02:00 -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: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes X-SW-Source: 2017-02/txt/msg01223.txt.bz2 On 02/17/2017 10:11 AM, Richard Biener wrote: > Index: gcc/fwprop.c > =================================================================== > --- gcc/fwprop.c (revision 245501) > +++ gcc/fwprop.c (working copy) > @@ -1478,7 +1478,8 @@ fwprop (void) > Do not forward propagate addresses into loops until after unrolling. > CSE did so because it was able to fix its own mess, but we are not. */ > > - for (i = 0; i < DF_USES_TABLE_SIZE (); i++) > + unsigned sz = DF_USES_TABLE_SIZE (); > + for (i = 0; i < sz; i++) > { > df_ref use = DF_USES_GET (i); > if (use) > > might work? (not knowing too much about this detail of the DF data > structures - can the table shrink?) This would probably work to fix the bug, but this behaviour is explicitly documented as intentional (in the comment the second half of which you've quoted). I assume it enables additional substitutions. Bernd