From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 13787 invoked by alias); 6 Jan 2014 13:39:23 -0000 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 Received: (qmail 13744 invoked by uid 48); 6 Jan 2014 13:39:20 -0000 From: "jakub at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug target/59644] [4.9 Regression] r206243 miscompiles Linux kernel Date: Mon, 06 Jan 2014 13:39:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: target X-Bugzilla-Version: 4.9.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: jakub at gcc dot gnu.org X-Bugzilla-Status: ASSIGNED X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: jakub at gcc dot gnu.org X-Bugzilla-Target-Milestone: 4.9.0 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_status cf_reconfirmed_on assigned_to everconfirmed attachments.created Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-SW-Source: 2014-01/txt/msg00536.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59644 Jakub Jelinek changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |ASSIGNED Last reconfirmed| |2014-01-06 Assignee|unassigned at gcc dot gnu.org |jakub at gcc dot gnu.org Ever confirmed|0 |1 --- Comment #23 from Jakub Jelinek --- Created attachment 31755 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=31755&action=edit gcc49-pr59644.patch Untested fix. For the code quality cases this patch regresses, perhaps it would be nice to have some LRA target hook where we could finalize the stack realign flags earlier, still during LRA, but late enough that nothing would need to be spilled in the various vector modes, if LRA would be able to cope with just reshuffling the elimination offsets because of that (and even better if it could deal with frame_pointer_needed -> !frame_pointer_needed change at that point). Vlad, do you think there could be such place in LRA (surely it would need to be done before the final lra_eliminate). If we could even more accurately find out if we really need aligned stack or not then, I'd hope it could improve code quality.