From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 29504 invoked by alias); 18 Nov 2012 18:47:32 -0000 Received: (qmail 29461 invoked by uid 22791); 18 Nov 2012 18:47:31 -0000 X-SWARE-Spam-Status: No, hits=-2.9 required=5.0 tests=AWL,BAYES_00,KHOP_THREADED 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; Sun, 18 Nov 2012 18:47:21 +0000 Received: from localhost (localhost [127.0.0.1]) by filtered-smtp.eu.adacore.com (Postfix) with ESMTP id 46D2CCB174C; Sun, 18 Nov 2012 19:47:23 +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 nIou6jK-1Qk0; Sun, 18 Nov 2012 19:47:23 +0100 (CET) Received: from polaris.localnet (bon31-6-88-161-99-133.fbx.proxad.net [88.161.99.133]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mel.act-europe.fr (Postfix) with ESMTP id BA761CB0554; Sun, 18 Nov 2012 19:47:22 +0100 (CET) From: Eric Botcazou To: Jan Hubicka Cc: gcc-patches@gcc.gnu.org, jakub@redhat.com Subject: Re: Reduce complette unrolling & peeling limits Date: Sun, 18 Nov 2012 18:47:00 -0000 Message-ID: <3701798.hzb6LFUzXT@polaris> User-Agent: KMail/4.7.2 (Linux/3.1.10-1.16-desktop; KDE/4.7.2; x86_64; ; ) In-Reply-To: <20121118170852.GA18650@kam.mff.cuni.cz> References: <20121114233407.GC12910@kam.mff.cuni.cz> <20121118165230.GC27832@atrey.karlin.mff.cuni.cz> <20121118170852.GA18650@kam.mff.cuni.cz> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" 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: 2012-11/txt/msg01508.txt.bz2 > OK, here are multiple issues. > 1) recursive inlining makes huge loop nest (of 18 loops) > 2) SCEV is very slow on answering simple_iv tests in this case becuase it > walks the nest > 3) unroller is computing loop body size even when it is clear the body is > much larger than the limit (the outer loop has 78000 instructions) > > I will prepare patches to fix those issues. Thanks for the analysis (and don't worry, I won't revert anything :-). -- Eric Botcazou