From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 13054 invoked by alias); 10 Feb 2015 02:19:42 -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 13034 invoked by uid 89); 10 Feb 2015 02:19:42 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=AWL,BAYES_00,SPF_PASS autolearn=ham version=3.3.2 X-HELO: service87.mimecast.com Received: from service87.mimecast.com (HELO service87.mimecast.com) (91.220.42.44) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Tue, 10 Feb 2015 02:19:41 +0000 Received: from cam-owa1.Emea.Arm.com (fw-tnat.cambridge.arm.com [217.140.96.140]) by service87.mimecast.com; Tue, 10 Feb 2015 02:19:38 +0000 Received: from SHAWIN202 ([10.1.255.212]) by cam-owa1.Emea.Arm.com with Microsoft SMTPSVC(6.0.3790.3959); Tue, 10 Feb 2015 02:19:36 +0000 From: "Thomas Preud'homme" To: "'Andrew Pinski'" Cc: "Eric Botcazou" , "GCC Patches" References: <00f001d044d4$23f37e20$6bda7a60$@arm.com> In-Reply-To: Subject: RE: [PATCH 1/2, combine] Try REG_EQUAL for nonzero_bits Date: Tue, 10 Feb 2015 02:19:00 -0000 Message-ID: <00f201d044d8$0131ccd0$03956670$@arm.com> MIME-Version: 1.0 X-MC-Unique: 115021002193800401 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-IsSubscribed: yes X-SW-Source: 2015-02/txt/msg00598.txt.bz2 > From: Andrew Pinski [mailto:pinskia@gmail.com] > Sent: Tuesday, February 10, 2015 9:57 AM > > +#ifdef SHORT_IMMEDIATES_SIGN_EXTEND > > +/* If MODE has a precision lower than PREC and SRC is a non-negative > constant > > + that would appear negative in MODE, sign-extend SRC for use in > nonzero_bits > > + because some machines (maybe most) will actually do the sign- > extension and > > + this is the conservative approach. > > + > > + ??? For 2.5, try to tighten up the MD files in this regard instead = of > this > > + kludge. */ >=20 > I don't know if this has been mentioned and even though you are just > copying a comment from below but would it make sense to look fixing > what the comment says we should look at after GCC 2.5 (which was over > 20 years ago)? Or maybe just remove the comment if it no longer > applies. Actually this bit seems unnecessary as there is already some logic in nonzero_bits1 for the CONST_INT case. So I guess the code can be removed and the comment be moved there at the very least but I'd prefer people from one of the affected target to test it. Looking for backend that define SHORT_IMMEDIATES_SIGN_EXTEND, that would be someone interested in alpha, frv, lm32, m32r, mep, mips, rs6000, rx, sh, tilegx or tilepro. Best regards, Thomas