From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 6764 invoked by alias); 3 Nov 2010 18:49:24 -0000 Received: (qmail 6756 invoked by uid 22791); 3 Nov 2010 18:49:24 -0000 X-SWARE-Spam-Status: No, hits=-2.0 required=5.0 tests=AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from mel.act-europe.fr (HELO mel.act-europe.fr) (194.98.77.210) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 03 Nov 2010 18:49:20 +0000 Received: from localhost (localhost [127.0.0.1]) by filtered-smtp.eu.adacore.com (Postfix) with ESMTP id 5E869CB0305; Wed, 3 Nov 2010 19:49:18 +0100 (CET) Received: from mel.act-europe.fr ([127.0.0.1]) by localhost (smtp.eu.adacore.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id jrrqIh4Jm2AJ; Wed, 3 Nov 2010 19:49:18 +0100 (CET) Received: from [192.168.1.2] (bon31-9-83-155-120-49.fbx.proxad.net [83.155.120.49]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mel.act-europe.fr (Postfix) with ESMTP id 3F619CB0303; Wed, 3 Nov 2010 19:49:18 +0100 (CET) From: Eric Botcazou To: Paolo Bonzini Subject: Re: new sign/zero extension elimination pass Date: Wed, 03 Nov 2010 18:50:00 -0000 User-Agent: KMail/1.9.9 Cc: Tom de Vries , gcc-patches@gcc.gnu.org, Bernd Schmidt References: <4CBC698B.3080204@codesourcery.com> <201010221030.30363.ebotcazou@adacore.com> <4CC9E7A5.8040404@gnu.org> In-Reply-To: <4CC9E7A5.8040404@gnu.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <201011031947.38257.ebotcazou@adacore.com> 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: 2010-11/txt/msg00335.txt.bz2 > Rather than on DU chains (which are a very expensive problem just > because of its asymptotic complexity, so it's better to use it only on > small regions such as loops), I'd be picky about usage of note_uses, > which can be very simply replaced by a loop over the DF_INSN_USES vector. Indeed, that would already be better. -- Eric Botcazou