From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,9a441a9594e85d08 X-Google-Attributes: gid103376,public From: "Nick Roberts" Subject: Re: Bignum modular types in Ada95 Date: 1998/01/31 Message-ID: <01bd2e92$1ce64d80$LocalHost@xhv46.dial.pipex.com>#1/1 X-Deja-AN: 320946265 Content-Transfer-Encoding: 7bit References: <34CE568C.55D7E23D@cl.cam.ac.uk> <34CF3E78.F816DB5@cl.cam.ac.uk> <34D04FFD.41C6@cl.cam.ac.uk> Content-Type: text/plain; charset=ISO-8859-1 Organization: UUNet UK server (post doesn't reflect views of UUNet UK) Mime-Version: 1.0 Newsgroups: comp.lang.ada Date: 1998-01-31T00:00:00+00:00 List-Id: Point taken, but I have another question. Traditional bignums (e.g. in LISP) are dynamically extensible: they can change size during run-time to fit the actual value stored. For some applications, this approach would make sense, but for others it may not. So what approach to take: dynamically resizing, statically sized, or both? And if both, how to choose (depending on the range, by a representaion clause, by a pragma, or something else)? -- == Nick Roberts ================================================ == Croydon, UK =========================== == ================ == Proprietor, ThoughtWing Software ========== == Independent Software Development Consultant ====== == Nick.Roberts@dial.pipex.com ==== == Voicemail & Fax +44 181-405 1124 === == == == I live not in myself, but I become == === Portion of that around me; and to me == ==== High mountains are a feeling, but the hum == ======= Of human cities torture. =========== -- Byron [Childe Harold] Markus Kuhn wrote in article <34D04FFD.41C6@cl.cam.ac.uk>... > Robert A Duff wrote: > > >Handling 1024-bit integer arithmetic in the Ada compiler and not in > > >some library package has the advantage that the compiler will later > > >be able to do much better optimization (e.g. automatic register > > >allocation), once we get CPUs with 1024-bit integer registers and > > >ALUs, which I expect to happen in the next three years. > > > > Are you talking about special-purpose hardware? I doubt if 1024-bit > > registers will exist in general-purpose computers any time soon. (I > > reserve the right to redefine "soon" at will.) > > No, I am talking about the standard off-the-shelf Pentium > successor in a few years, not about any exotic special hardware. > IPv6 and electronic commerce will make it necessary that normal > workstations can to thousands of 1024-bit modexp operations per > second for authentication protocols. This is commonly expected to > be the next major functional extention after MMX. > > 20-dollar smartcard microcontrollers have such 1024-bit registers/ALUs > already available today. It is just a matter of time until we > see them in workstation processors. > > > Anyway, having the feature "built in" gives other advantages: literals, > > range checking, case_statements, etc. None of that works with some > > library package (unfortunately). > > Agree. Dear Ada compiler developers, please have a look again at > builtin bignum support!