From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 1831 invoked by alias); 20 Oct 2004 21:13:35 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 1820 invoked from network); 20 Oct 2004 21:13:34 -0000 Received: from unknown (HELO dberlin.org) (68.164.203.246) by sourceware.org with SMTP; 20 Oct 2004 21:13:34 -0000 Received: from [129.34.20.23] (HELO [9.2.217.169]) by dberlin.org (CommuniGate Pro SMTP 4.2.1) with ESMTP id 7401896; Wed, 20 Oct 2004 17:13:33 -0400 In-Reply-To: <1098306201.22552.63.camel@localhost.localdomain> References: <1098293613.22552.36.camel@localhost.localdomain> <1098294982.22552.38.camel@localhost.localdomain> <1098304350.22552.47.camel@localhost.localdomain> <04DB6F48-22D8-11D9-B310-000D93B1B044@dberlin.org> <1098305368.22552.57.camel@localhost.localdomain> <531813B6-22DA-11D9-B310-000D93B1B044@dberlin.org> <1098306201.22552.63.camel@localhost.localdomain> Mime-Version: 1.0 (Apple Message framework v619) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: Content-Transfer-Encoding: 7bit Cc: "gcc-patches@gcc.gnu.org" , Andrew Macleod From: Daniel Berlin Subject: Re: [PATCH]: Implement must-def kill operand Date: Wed, 20 Oct 2004 21:27:00 -0000 To: Diego Novillo X-SW-Source: 2004-10/txt/msg01776.txt.bz2 On Oct 20, 2004, at 5:03 PM, Diego Novillo wrote: > On Wed, 2004-10-20 at 16:55, Daniel Berlin wrote: > >> That will, in turn, mark the *feeders* of the phi as necessary, >> because >> they will be added to the worklist, and propagate_necessity doesn't >> know that it doesn't need to mark the feeders unless they are phi >> nodes, thus you will miss dead code being eliminated. >> > Ah, good point. Sigh. I think I'm about to ask you to just let the > regular renamer run and insert needed PHIs, but I agree that PHI node > churn should be avoided. > > How much additional code are we talking about? All told, including all necessary changes to DCE and comments, it's 89 lines of code added. > A good chunk of the > algorithm you described already exists in DCE. Can it be factored? I factored what i could. :) > > > Diego. >