From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 10853 invoked by alias); 8 Aug 2010 12:09:29 -0000 Received: (qmail 10842 invoked by uid 22791); 8 Aug 2010 12:09:28 -0000 X-SWARE-Spam-Status: No, hits=-1.3 required=5.0 tests=AWL,BAYES_00,RCVD_NUMERIC_HELO,SPF_HELO_PASS,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from lo.gmane.org (HELO lo.gmane.org) (80.91.229.12) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sun, 08 Aug 2010 12:09:26 +0000 Received: from list by lo.gmane.org with local (Exim 4.69) (envelope-from ) id 1Oi4gs-0006iu-Ss for gcc-patches@gcc.gnu.org; Sun, 08 Aug 2010 14:09:22 +0200 Received: from 12.198.177.3 ([12.198.177.3]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sun, 08 Aug 2010 14:09:22 +0200 Received: from bonzini by 12.198.177.3 with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sun, 08 Aug 2010 14:09:22 +0200 To: gcc-patches@gcc.gnu.org From: Paolo Bonzini Subject: Re: [PATCH] Keep lattice abstract in the SSA propagator, substitue lattice values at defs Date: Sun, 08 Aug 2010 12:12:00 -0000 Message-ID: <4C5E9E67.7090004@gnu.org> References: <20100804123142.GA83420@adacore.com> <201008081000.41310.ebotcazou@adacore.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Eric Botcazou , gcc-patches@gcc.gnu.org, Arnaud Charlet User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.10) Gecko/20100621 Fedora/3.0.5-1.fc13 Lightning/1.0b2pre Thunderbird/3.0.5 In-Reply-To: X-IsSubscribed: yes 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 X-SW-Source: 2010-08/txt/msg00591.txt.bz2 Message-ID: <20100808121200.FYWWkmY8Y6z3HSVn0OSQi1CmsGz4OdlgRiWn75aegsQ@z> On 08/08/2010 04:44 AM, Richard Guenther wrote: > arithmetic. But - we can do so if reassociating constants only > as in the example above. Because if (L43b_216 - 1) - 2147483648 > doesn't overflow then L43b_216 + 2147483647 doesn't either. Huh? a - 1 - 2147483648 is valid if a >= 1. a + 2147483647 is valid if a < 1. Paolo