From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7166 invoked by alias); 19 Dec 2002 01:28:07 -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 7157 invoked from network); 19 Dec 2002 01:28:05 -0000 Received: from unknown (HELO nile.gnat.com) (205.232.38.5) by 209.249.29.67 with SMTP; 19 Dec 2002 01:28:05 -0000 Received: by nile.gnat.com (Postfix, from userid 338) id 5F8D8F28D5; Wed, 18 Dec 2002 20:27:54 -0500 (EST) To: rth@redhat.com, toon@moene.indiv.nluug.nl Subject: Re: possible gcse failure: not able to eliminate redundant loads Cc: gcc@gcc.gnu.org Message-Id: <20021219012754.5F8D8F28D5@nile.gnat.com> Date: Wed, 18 Dec 2002 18:39:00 -0000 From: dewar@gnat.com (Robert Dewar) X-SW-Source: 2002-12/txt/msg01174.txt.bz2 > i.e. the dereference is protected by a conditional. Thus > we can't hoist the dereference past the conditional (and > thence out of the loop that started this thread). it is interesting to note that the IBM compiler group decided that ensuring that null could be safetly dereferenced, and hence such references can be hoisted etc, was a major win in C code efficiency.