From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on yquem.inria.fr X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=none autolearn=disabled version=3.1.3 Received: from mail1-relais-roc.national.inria.fr (mail1-relais-roc.national.inria.fr [192.134.164.82]) by yquem.inria.fr (Postfix) with ESMTP id 73DCBBC37; Sun, 10 May 2009 13:04:23 +0200 (CEST) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Aj4CAEVRBkrUGyoEk2dsb2JhbACPeYcYAQEBAQkJCgkRA7RQB4N3BQ X-IronPort-AV: E=Sophos;i="4.38,431,1233529200"; d="scan'208";a="29023322" Received: from smtp4-g21.free.fr ([212.27.42.4]) by mail1-smtp-roc.national.inria.fr with ESMTP; 10 May 2009 13:04:22 +0200 Received: from smtp4-g21.free.fr (localhost [127.0.0.1]) by smtp4-g21.free.fr (Postfix) with ESMTP id 692C04C808E; Sun, 10 May 2009 13:04:15 +0200 (CEST) Received: from erha (pat35-1-82-229-60-210.fbx.proxad.net [82.229.60.210]) by smtp4-g21.free.fr (Postfix) with ESMTP id 85F164C8113; Sun, 10 May 2009 13:04:13 +0200 (CEST) Received: by erha (Postfix, from userid 1000) id 4489758E0E4; Sun, 10 May 2009 13:04:13 +0200 (CEST) To: Xavier Leroy Cc: Dmitry Bely , Caml List Subject: Re: [Caml-list] Ocamlopt x86-32 and SSE2 References: <90823c940904281236x61204451nac149ee15b5df73a@mail.gmail.com> <4A0005C8.8010609@inria.fr> <90823c940905050241y11f012e5xee8316e3e4337ff9@mail.gmail.com> <4A0407A9.4000009@inria.fr> From: David MENTRE Organization: none Date: Sun, 10 May 2009 13:04:13 +0200 In-Reply-To: <4A0407A9.4000009@inria.fr> (Xavier Leroy's message of "Fri\, 08 May 2009 12\:21\:29 +0200") Message-ID: <87eiuxuslu.fsf@pat35-1-82-229-60-210.fbx.proxad.net> User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Spam: no; 0.00; ocamlopt:01 ocamlopt:01 command-line:01 gcc:01 byte-code:01 ocaml:01 gpg:01 caml-list:01 arithmetic:01 arithmetic:01 writes:01 native:03 float:03 float:03 processors:04 Hello, Xavier Leroy writes: > 1- Have an additional "ia32sse2" port of ocamlopt in parallel with the > current "i386" port. > > 2- Declare pre-SSE2 processors obsolete and convert the current > "i386" port to always use SSE2 float arithmetic. > > 3- Support both x87 and SSE2 float arithmetic within the same i386 > port, with a command-line option to activate SSE2, like gcc does. Regarding option 2, I assume that byte-code would still work on i386 pre-SSE2 machines? So OCaml programs would still work on those machines. As far as I know, one is using ocamlopt to improve performance. I can't think of any case where one would need native code running on pre-SS2 machines which are so outdated performance-wise. So I would vote for option 2: always use SSE2 float arithmetic. Sincerely yours, david -- GPG/PGP key: A3AD7A2A David MENTRE 5996 CC46 4612 9CA4 3562 D7AC 6C67 9E96 A3AD 7A2A