From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 4621 invoked by alias); 26 Mar 2004 18:10:36 -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 4602 invoked from network); 26 Mar 2004 18:10:35 -0000 Received: from unknown (HELO atrey.karlin.mff.cuni.cz) (195.113.31.123) by sources.redhat.com with SMTP; 26 Mar 2004 18:10:35 -0000 Received: by atrey.karlin.mff.cuni.cz (Postfix, from userid 29025) id 5A3024C031C; Fri, 26 Mar 2004 19:10:34 +0100 (CET) Date: Fri, 26 Mar 2004 18:51:00 -0000 From: Zdenek Dvorak To: Dale Johannesen Cc: "gcc@gcc.gnu.org list" Subject: Re: [tree-ssa vs lno] who is right? Message-ID: <20040326181034.GA24586@atrey.karlin.mff.cuni.cz> References: <086B964A-7EC5-11D8-8C7F-000A95D7CD40@apple.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <086B964A-7EC5-11D8-8C7F-000A95D7CD40@apple.com> User-Agent: Mutt/1.5.4i X-SW-Source: 2004-03/txt/msg01567.txt.bz2 Hello, > When the LNO branch copies a loop, it attempts to fix up the phi nodes > with > an algorithm that assumes there is only one phi per block per variable. > That is, it > won't see code like this: where do we assume this (i.e. what do you mean by "copying a loop")? While this certainly is unlikely to happen, there probably is nothing that would prevent it. Zdenek > ;; basic block 19, loop depth 0, count 0 > ;; prev block 9, next block 20 > ;; pred: 10 [100.0%] (fallthru) > ;; succ: 28 [50.0%] (true,exec) 29 [50.0%] (false,exec) > # maxmin_Result_140 = PHI <1(10)>; > # maxmin_Result_142 = PHI <2(10)>; > # lsm_tmp.19_144 = PHI ; > :; > if (m__10 == 0) goto ; else goto ; > > Is that suppose to be a valid assumption? The dup is created by > copyrename, and > I see no code there that's intended to stop dups from being created (on > the > contrary, but surely it's unusual for the live ranges to overlap). >