From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (from majordomo@localhost) by pauillac.inria.fr (8.7.6/8.7.3) id LAA27404; Fri, 2 Aug 2002 11:58:00 +0200 (MET DST) X-Authentication-Warning: pauillac.inria.fr: majordomo set sender to owner-caml-list@pauillac.inria.fr using -f Received: from nez-perce.inria.fr (nez-perce.inria.fr [192.93.2.78]) by pauillac.inria.fr (8.7.6/8.7.3) with ESMTP id LAA27393 for ; Fri, 2 Aug 2002 11:57:59 +0200 (MET DST) Received: from web11208.mail.yahoo.com (web11208.mail.yahoo.com [216.136.131.190]) by nez-perce.inria.fr (8.11.1/8.11.1) with SMTP id g729vvf15090 for ; Fri, 2 Aug 2002 11:57:58 +0200 (MET DST) Message-ID: <20020802095756.99352.qmail@web11208.mail.yahoo.com> Received: from [195.224.189.78] by web11208.mail.yahoo.com via HTTP; Fri, 02 Aug 2002 02:57:56 PDT Date: Fri, 2 Aug 2002 02:57:56 -0700 (PDT) From: Noel Welsh Subject: RE: ocaml, simd, & fftwgel RE: [Caml-list] Caml productivity. To: "Gurr, David \(MED, self\)" Cc: caml-list@inria.fr In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-caml-list@pauillac.inria.fr Precedence: bulk --- "Gurr, David (MED, self)" wrote: > > But do they do a better job than fftwgel or Spiral > or Atlas? I have no idea :) > Is SAC available for public inspection? Yeah: http://www.informatik.uni-kiel.de/~sacbase/ I couldn't find a paper that describes how ATLAS is implemented. I'm guessing the most important optimisations are blocking (dependant on the cache size) and condensing consequetive array transversals. SAC does both these optimisations. > Once you do this, it is much less > clear what > the value added of the C compiler is. In > particular, the amount of > refinement that would be needed to get ocamlopt to > match C compilers > at this task might be relatively small ... since C > is notoriously > difficult to optimize even without SIMD. Yeah, it is kinda ironic that C is famous for generating such fast C. The functional model (pure functional code is essentially an SSA register machine) is much closer to current hardware than the C every-has-an-address/stack model. So it should be possible to get fast code out of a functional language with less effort than C. It is also a bit amusing, and a bit sad, that Java and .Net both use a stack model (it's like they want slow code!) Noel __________________________________________________ Do You Yahoo!? Yahoo! Health - Feel better, live better http://health.yahoo.com ------------------- To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/ Beginner's list: http://groups.yahoo.com/group/ocaml_beginners