From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 22060 invoked by alias); 17 May 2016 22:34:14 -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 22041 invoked by uid 89); 17 May 2016 22:34:14 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-0.5 required=5.0 tests=AWL,BAYES_00,KAM_LAZY_DOMAIN_SECURITY,RCVD_IN_DNSWL_NONE autolearn=no version=3.3.2 spammy=HX-Envelope-From:sk:ebotcaz, experimenting, H*F:U*ebotcazou, HContent-Transfer-Encoding:7Bit X-HELO: smtp.eu.adacore.com Received: from mel.act-europe.fr (HELO smtp.eu.adacore.com) (194.98.77.210) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES256-GCM-SHA384 encrypted) ESMTPS; Tue, 17 May 2016 22:34:12 +0000 Received: from localhost (localhost [127.0.0.1]) by filtered-smtp.eu.adacore.com (Postfix) with ESMTP id EF356812EA; Wed, 18 May 2016 00:34:09 +0200 (CEST) Received: from smtp.eu.adacore.com ([127.0.0.1]) by localhost (smtp.eu.adacore.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id csicmRBlb5Ae; Wed, 18 May 2016 00:34:09 +0200 (CEST) Received: from polaris.localnet (bon31-6-88-161-99-133.fbx.proxad.net [88.161.99.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.eu.adacore.com (Postfix) with ESMTPSA id B48C3812E9; Wed, 18 May 2016 00:34:08 +0200 (CEST) From: Eric Botcazou To: Segher Boessenkool Cc: gcc-patches@gcc.gnu.org Subject: Re: [PATCH 1/3] function: Do the CLEANUP_EXPENSIVE after shrink-wrapping, not before Date: Tue, 17 May 2016 22:34:00 -0000 Message-ID: <2877683.FHcDiREYmD@polaris> User-Agent: KMail/4.14.10 (Linux/3.16.7-35-desktop; KDE/4.14.9; x86_64; ; ) In-Reply-To: <20160517222254.GA5146@gate.crashing.org> References: <213485283eede9da12b217737d95fc8f5c4be442.1463428211.git.segher@kernel.crashing.org> <20160517091758.GC18363@gate.crashing.org> <20160517222254.GA5146@gate.crashing.org> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-SW-Source: 2016-05/txt/msg01293.txt.bz2 > I built cross-compilers for 30 targets, and built Linux with that. > 6 of those failed for unrelated reasons. Of the 24 that do build, > five show a few insns difference between having a cleanup_cfg before > shrink-wrapping or not (CLEANUP_EXPENSIVE made no difference there). > These targets are s390, blackfin, m68k, mn10300, nios2. Interesting, thanks for experimenting. > It turns out that prepare_shrink_wrap *does* care about block structure: > namely, it only moves insns from the "head" block to a successor. It > then makes a difference when the cleanup_cfg can merge two successor blocks > (say, the first is a forwarder block). This happens quite seldomly. > > So, shall I put a cleanup_cfg back before shrink-wrapping? Yes, I'd only swap CLEANUP_EXPENSIVE with 0, i.e. leave the calls themselves and add a comment on the first one saying that this helps shrink-wrapping too. -- Eric Botcazou