From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 19266 invoked by alias); 19 Jan 2004 13:26:49 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 19256 invoked from network); 19 Jan 2004 13:26:48 -0000 Received: from unknown (HELO sophia.inria.fr) (138.96.64.20) by sources.redhat.com with SMTP; 19 Jan 2004 13:26:48 -0000 Received: from localhost (localhost [127.0.0.1]) by sophia.inria.fr (8.12.10/8.12.9) with ESMTP id i0JDQjLQ024523; Mon, 19 Jan 2004 14:26:45 +0100 Received: from mururoa.inria.fr (mururoa.inria.fr [138.96.80.8]) by sophia.inria.fr (8.12.10/8.12.9) with ESMTP id i0JD0tZ5028173; Mon, 19 Jan 2004 14:00:57 +0100 Received: from mururoa.inria.fr (papadop@localhost) by mururoa.inria.fr (8.12.10/8.12.5) with ESMTP id i0JD0sm7002794; Mon, 19 Jan 2004 14:00:54 +0100 Message-Id: <200401191300.i0JD0sm7002794@mururoa.inria.fr> To: kenner@vlsi1.ultra.nyu.edu (Richard Kenner) cc: hubicka@ucw.cz, gcc@gcc.gnu.org Subject: Re: [RFC] Contributing tree-ssa to mainline In-Reply-To: <10401191226.AA27734@vlsi1.ultra.nyu.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Mon, 19 Jan 2004 13:26:00 -0000 From: Theodore Papadopoulo X-Virus-Scanned: by amavisd-new at sophia.inria.fr X-SW-Source: 2004-01/txt/msg01274.txt.bz2 kenner@vlsi1.ultra.nyu.edu said: > A case I know about in Ada is check elimination. Because the default > for Ada is enabling checking, it's quite important to eliminate checks > that can be proven not to fail. Theoretically, a lot this could be > language-independent optimizers by value range propagation and related > optimizations. But the front-end can do a much better job because it > has information only it knows. Moreover, by suppressing the check > before generating any code for it, compilation time is reduced. I > think this is clearly the proper place for that optimization. AFAIK, tree-ssa would be beneficial in this situation. By making the check elimination work on GIMPLE (I hope it is the proper place), this would remove this from the ADA front-end and generalize to other languages. I assume that the sole introduction of optimization on trees allow you to move some code out of the front-end to the tree optimization passes of tree-ssa. That being said, as an exterior observer, what I can say is that we have seen quite a few major contributors switching to tree-ssa recently... This is surely partially because gcc-3.4 was in stage 3, but the move has been more marked than for previous releases IMHO. Having the work-forces (rougthly) splitted in two is not a good thing IMO. That should be considered... -------------------------------------------------------------------- Theodore Papadopoulo Email: Theodore.Papadopoulo@sophia.inria.fr Tel: (33) 04 92 38 76 01 --------------------------------------------------------------------