From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:52363) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RFPwO-0004S3-Fk for qemu-devel@nongnu.org; Sun, 16 Oct 2011 08:35:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RFPwN-0004DY-L9 for qemu-devel@nongnu.org; Sun, 16 Oct 2011 08:35:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38573) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RFPwN-0004D8-B9 for qemu-devel@nongnu.org; Sun, 16 Oct 2011 08:35:43 -0400 Message-ID: <4E9ACF99.9020507@redhat.com> Date: Sun, 16 Oct 2011 14:35:37 +0200 From: Avi Kivity MIME-Version: 1.0 References: <1318387026-21569-1-git-send-email-david@gibson.dropbear.id.au> <4E9AAA33.3010806@redhat.com> <20111016114011.GG4580@truffala.fritz.box> In-Reply-To: <20111016114011.GG4580@truffala.fritz.box> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] Memory API bugfix - abolish addrrrange_end() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: anthony@codemonkey.ws, agraf@suse.de, aik@ozlabs.ru, qemu-devel@nongnu.org On 10/16/2011 01:40 PM, David Gibson wrote: > > Let me see if I can work up a synthetic int128 type. > > So.. you think replacing every single basic arithmetic operations with > calls to implement the synthetic type, _and_ imposing the resulting > overhead is _less_ ugly than some slightly fiddly re-ordering of > operations? Seriously? > In terms of how the code looks, it's seriously more ugly (see the patches I sent out). Conceptually it's cleaner, since we're not dodging the issue that we need to deal with a full 64-bit domain. But my main concern is maintainability. The 64-bit blanket is to short, if we keep pulling it in various directions we'll just expose ourselves in new ways. The overhead is negligible. This code comes nowhere near any fast path. -- error compiling committee.c: too many arguments to function