From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 3203 invoked by alias); 16 Jan 2012 14:32:23 -0000 Received: (qmail 3192 invoked by uid 22791); 16 Jan 2012 14:32:22 -0000 X-SWARE-Spam-Status: No, hits=-2.1 required=5.0 tests=AWL,BAYES_00,TW_FW,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from VLSI1.ULTRA.NYU.EDU (HELO vlsi1.ultra.nyu.edu) (128.122.140.213) by sourceware.org (qpsmtpd/0.43rc1) with SMTP; Mon, 16 Jan 2012 14:32:01 +0000 Received: by vlsi1.ultra.nyu.edu (4.1/1.34) id AA18637; Mon, 16 Jan 12 09:34:33 EST From: kenner@vlsi1.ultra.nyu.edu (Richard Kenner) Message-Id: <11201161434.AA18637@vlsi1.ultra.nyu.edu> Date: Mon, 16 Jan 2012 14:32:00 -0000 To: uweigand@de.ibm.com Subject: Re: RFC: allowing fwprop to propagate subregs Cc: bonzini@gnu.org, gcc-patches@gcc.gnu.org, richard.sandiford@linaro.org In-Reply-To: <201201161421.q0GELNJA032443@d06av02.portsmouth.uk.ibm.com> References: <201201161421.q0GELNJA032443@d06av02.portsmouth.uk.ibm.com> Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org X-SW-Source: 2012-01/txt/msg00783.txt.bz2 > Maybe the best solution would be to remove the SUBREG case from the generic > apply_distributive_law subroutine, and instead add a special check for the > distributed subreg case right at the above place in simplify_set; i.e. to > perform the inverse distribution only if it is already guaranteed that we > will also be able to move the subreg to the LHS ... That could indeed work.