From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 52154 invoked by alias); 20 May 2016 16:08:42 -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 52137 invoked by uid 89); 20 May 2016 16:08:42 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-3.3 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=late, H*MI:sk:2016052 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 (AES256-GCM-SHA384 encrypted) ESMTPS; Fri, 20 May 2016 16:08:41 +0000 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (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 A037562640; Fri, 20 May 2016 16:08:39 +0000 (UTC) Received: from tucnak.zalov.cz (ovpn-116-88.ams2.redhat.com [10.36.116.88]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u4KG8bNJ015345 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Fri, 20 May 2016 12:08:39 -0400 Received: from tucnak.zalov.cz (localhost [127.0.0.1]) by tucnak.zalov.cz (8.15.2/8.15.2) with ESMTP id u4KG8awu027281; Fri, 20 May 2016 18:08:36 +0200 Received: (from jakub@localhost) by tucnak.zalov.cz (8.15.2/8.15.2/Submit) id u4KG8Z7u027280; Fri, 20 May 2016 18:08:35 +0200 Date: Fri, 20 May 2016 16:08:00 -0000 From: Jakub Jelinek To: Andi Kleen Cc: gcc-patches@gcc.gnu.org Subject: Re: [PATCH][RFC] Introduce BIT_FIELD_INSERT Message-ID: <20160520160834.GM28550@tucnak.redhat.com> Reply-To: Jakub Jelinek References: <87r3cwes8x.fsf@tassilo.jf.intel.com> <20160520155439.GU13997@two.firstfloor.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160520155439.GU13997@two.firstfloor.org> User-Agent: Mutt/1.5.24 (2015-08-30) X-IsSubscribed: yes X-SW-Source: 2016-05/txt/msg01669.txt.bz2 On Fri, May 20, 2016 at 08:54:39AM -0700, Andi Kleen wrote: > I thought I had filed a bugzilla at some point, but can't > find it right now. If you compare bitfield code > compiled for Haswell on LLVM and GCC it is very visible > how much worse gcc is. We really need to lower bitfield operations (especially when there are multiple adjacent ones) to integer arithmetics on the underlying DECL_BIT_FIELD_REPRESENTATIVE fields somewhere in (late?) gimple and perform some cleanups after it and only after that expand. Jakub