From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 1193 invoked by alias); 19 Jan 2012 13:12:09 -0000 Received: (qmail 1151 invoked by uid 22791); 19 Jan 2012 13:12:08 -0000 X-SWARE-Spam-Status: No, hits=-2.9 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from localhost (HELO gcc.gnu.org) (127.0.0.1) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Thu, 19 Jan 2012 13:11:56 +0000 From: "jakub at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/51895] [4.7 Regression] ICE in simplify_subreg Date: Thu, 19 Jan 2012 13:32:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: middle-end X-Bugzilla-Keywords: ice-on-valid-code X-Bugzilla-Severity: normal X-Bugzilla-Who: jakub at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Priority: P1 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: 4.7.0 X-Bugzilla-Changed-Fields: CC Message-ID: In-Reply-To: References: X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2012-01/txt/msg02144.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51895 Jakub Jelinek changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |ebotcazou at gcc dot | |gnu.org --- Comment #7 from Jakub Jelinek 2012-01-19 13:11:13 UTC --- (In reply to comment #6) > > Untested patch that attempts to fix BLKmode MEM_REF expansion with > > non-DECL_ADDRESSABLE non-BLKmode base. It creates abysmal code, so IMNSHO > > eipa_sra should be fixed not to do this. > > Hm, can't we do better using extract_bit_field? I mean, it definitely > should work to do any BIT_FIELD_REF on an rvalue, even if it is a register. > The patch from comment #1 doesn't look completely wrong, it just seems that > the caller should have catered for using the mode of the reg. The docs > of operand_subword also say 'MODE is the mode of OP in case it is a CONST_INT' > so MODE should be irrelevant if REG_P (op) ... > > Seems to be a tricky area, but using a stack temporary looks like overkill. We don't have BLKmode pseudos, the only thing that can be BLKmode is MEM. So I'm afraid we can't avoid that. E.g. VIEW_CONVERT_EXPR of a TImode value to BLKmode value would be expanded by spilling the TImode value to a stack temporary and adjust_address it to BLKmode too.