From owner-freebsd-questions@FreeBSD.ORG Mon Oct 4 21:33:08 2010 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id AB7F8106564A for ; Mon, 4 Oct 2010 21:33:08 +0000 (UTC) (envelope-from emailrob@emailrob.com) Received: from mx04.dls.net (mx04.dls.net [216.145.245.200]) by mx1.freebsd.org (Postfix) with ESMTP id 8EA4A8FC27 for ; Mon, 4 Oct 2010 21:33:08 +0000 (UTC) Received: from [216.145.235.31] (helo=emailrob.com) by mx04.dls.net with esmtp (Exim 4.69) (envelope-from ) id 1P2s3l-00039B-Jn; Mon, 04 Oct 2010 15:54:58 -0500 Message-ID: <4CAA3030.3090001@emailrob.com> Date: Mon, 04 Oct 2010 20:51:12 +0100 From: spellberg_robert User-Agent: Mozilla/5.0 (Windows; U; Win98; en-US; rv:1.0.2) Gecko/20030208 Netscape/7.02 X-Accept-Language: en-us, en MIME-Version: 1.0 To: fbsd_questions Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Subject: [fbsd_questions] i386 vs amd64, on intel_64 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 04 Oct 2010 21:33:08 -0000 howdy, y'all --- these may be stupid questions and, if so, i am prepared to slap my forehead with the palm of my hand. i recently acquired my first batch of intel cpus with 64_bit integer registers [ celeron 440 ], specifically for the 16 registers and the potential for a truly_gargantuan datasize. intel has called this many things, currently "intel 64 architecture". to me, this is just a bigger, faster "386", just like my "486" and several flavors of "pentium" [ now, all retired ]. i have never owned an amd cpu. this may be the source of my confusion. what prompted my recent searches was the observation, while working on my "killer_app", in , as i recall, that the size of an "intptr" is 32_bits. [ i am aware of the gcc "double_integer" implementation of "64_bit" data_integers. that is not the issue; i want big memory. ] i want my app to exist in two sizes, small [ 8_, 16_ and 32_bit integers and 32_bit pointers ] and large [ 8_, 16_, 32_ and 64_bit integers and 48_bit pointers ], the choice between the two being made by my users, according to their needs. my objective is to produce both versions, simultaneously. so, i have been looking at many pages, mostly at freebsd.org [ http and ftp ] and gcc.gnu.org, as well as some others [ release notes, in particular ]. the last question is the big one. consider a dvd_image [ to pick an approach ] of a release to be found on ftp.freebsd.org. q: if the release_name includes the string "i386", am i restricted to 8 32_bit registers and 32_bit pointers, notwithstanding its installation on an intel_64 platform ? next, from what i have been reading, those releases whose names contain "amd64" not only are for amd cpus, but, also, are for the intel_64 variant [ no doubt, probing the cpu for its feature_set ]. q: if i install an "amd64" version on an "intel_64" platform, am i restricted to 16 64_bit registers and 48_bit pointers or can i compile for both cpu_models [ perhaps, with nothing more complicated than a compiler option ] ? please cc. in advance, thanks big_time. rob