From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Original-To: caml-list@yquem.inria.fr Delivered-To: caml-list@yquem.inria.fr Received: from mail3-relais-sop.national.inria.fr (mail3-relais-sop.national.inria.fr [192.134.164.104]) by yquem.inria.fr (Postfix) with ESMTP id 533BCBC57 for ; Fri, 3 Dec 2010 22:16:49 +0100 (CET) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AoIAAJLt+ExKfVK0kGdsb2JhbACDUJJ4jGoIFQEBAgkJDAcRBB6pDoksglQBBY16AQSBIXOCQXM X-IronPort-AV: E=Sophos;i="4.59,295,1288566000"; d="scan'208";a="69181210" Received: from mail-wy0-f180.google.com ([74.125.82.180]) by mail3-smtp-sop.national.inria.fr with ESMTP; 03 Dec 2010 22:16:43 +0100 Received: by wyb29 with SMTP id 29so5126864wyb.39 for ; Fri, 03 Dec 2010 13:16:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:received:received:from:to:cc:references :in-reply-to:subject:date:organization:message-id:mime-version :content-type:content-transfer-encoding:x-mailer:thread-index :content-language; bh=KIWqT8KMSvyMGUjgGV5k0XJ0ayBxufhor4ZOJ61KUf0=; b=v0dGD3S/2Gm1pFTmci+KzUcBF0m37Z0TRPxO32DNLRkfZVJqHO/QkpoN0uE3Ci6ugX bowHDjB3bGigxc4aubtlP0PDTYvga7Ep91z6ychfkGq3FvCcFCZRzk9e8GcZEq6gB7sL trSc3ykntj2x5ygfR1JAnr/2a9X+xEjNYQ8QA= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=from:to:cc:references:in-reply-to:subject:date:organization :message-id:mime-version:content-type:content-transfer-encoding :x-mailer:thread-index:content-language; b=Atp+pBXZ69Mpm80lCI3MU32gWJ0Hr99mokIsMEmC9K2sinsS27m87n6fz6tMi6o6d0 wVd4zRH/aY8KB4obJE/SxFzQWsA3rN41WMwqIhb5I5MJ7wJV1CEJX+8q11e8WUDxsaLG /6iCgg3/JV48755E9XAoZ3zD2HcTYT12/nqaw= Received: by 10.227.141.139 with SMTP id m11mr2537674wbu.35.1291411002931; Fri, 03 Dec 2010 13:16:42 -0800 (PST) Received: from WinEight ([87.113.160.118]) by mx.google.com with ESMTPS id x12sm1115264weq.18.2010.12.03.13.16.40 (version=SSLv3 cipher=RC4-MD5); Fri, 03 Dec 2010 13:16:41 -0800 (PST) From: Jon Harrop To: "'Till Varoquaux'" Cc: References: <3DCEA910-1382-47E5-876B-059178F8F82E@googlemail.com> <20101130124803.7952fca1@deb0> <0a8b01cb90da$da5e6240$8f1b26c0$@com> <5E2DA3F1-7998-4F62-B617-7B6451D1001D@googlemail.com> <0b3b01cb9161$a81c8e10$f855aa30$@com> <0b9301cb91a3$8f42fd60$adc8f820$@com> In-Reply-To: Subject: RE: ocamlopt LLVM support (Was: [Caml-list] OCamlJIT2 vs. OCamlJIT) Date: Fri, 3 Dec 2010 21:16:06 -0000 Organization: Flying Frog Consultancy Message-ID: <0caf01cb932f$4d612830$e8237890$@com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Mailer: Microsoft Office Outlook 12.0 Thread-Index: AcuS7vT4nSx/YOQIRUuWsLMNX2gnSgAQDdaQ Content-Language: en-gb X-Spam: no; 0.00; ocamlopt:01 ocaml:01 compiler:01 combinator:01 functors:01 inlining:01 compiler:01 pointers:01 cheers:01 wrote:01 caml-list:01 functions:01 match:02 constraints:03 optimization:03 Till wrote: > You seem to think LLVM wouldn't actually buy us much in term of > optimisations. In my experience the current ocaml compiler is really > good when writing code fairly low level but discourages use of > combinator library, higher order functions, functors in performance > sensitive code (i.e. you have to do inlining, specialization, constant > propaagation etc... by hand). >=20 > I was under the impression that some of LLVM passes could be a good > match for those problems. That is: micro benchmark code that is > written carefully with those constraints in mind wouldn't gain much > but some form of "origami" programming could be unfolded by the > compiler. Am I missing something obvious? (e.g. need for better side > effect analysis). I doubt many of LLVM's optimization passes would kick in if the type = information has been removed by boxing and casting all the pointers to = i8*. Cheers, Jon.