From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 15056 invoked by alias); 18 May 2007 20:37:27 -0000 Received: (qmail 15048 invoked by uid 22791); 18 May 2007 20:37:26 -0000 X-Spam-Check-By: sourceware.org Received: from mx-out.libertysurf.net (HELO mail.libertysurf.net) (213.36.80.91) by sourceware.org (qpsmtpd/0.31) with ESMTP; Fri, 18 May 2007 20:37:21 +0000 Received: from [192.168.1.3] (91.165.157.202) by mail.libertysurf.net (7.3.118.8) id 4638CA01001E85B4; Fri, 18 May 2007 22:37:16 +0200 From: Eric Botcazou To: Ian Lance Taylor Subject: Re: [PATCH, x86_64]: Provide longlong.h definitions for 128bit =?iso-8859-1?q?=09operations?= Date: Fri, 18 May 2007 20:37:00 -0000 User-Agent: KMail/1.7.1 Cc: gcc-patches@gcc.gnu.org, Rask Ingemann Lambertsen , Uros Bizjak , Paolo Bonzini , Chris Lattner References: <464B6834.1050600@gmail.com> <200705180912.20137.ebotcazou@libertysurf.fr> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200705182238.36051.ebotcazou@libertysurf.fr> X-IsSubscribed: yes 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: 2007-05/txt/msg01244.txt.bz2 > From the backend perspective, the best way to take advantage of > lower-subreg is conceptually simple if sometimes awkward in practice: > for multi-word operations, use define_insn_and_split and split the > insns before reload. OK, I see, thanks. > For a non-CC0 style machine things are simpler. Just split multi-word > operations before reload. There was never any particular need to wait > until after reload to split them in the past. And now you really > don't want to wait. Of course SPARC-V8 is the perfect counter-example since you have a pairing instruction "ldd" for consecutive integer registers. :-) -- Eric Botcazou