From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 22889 invoked by alias); 27 May 2014 14:11:02 -0000 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 Received: (qmail 22868 invoked by uid 89); 27 May 2014 14:11:00 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-3.2 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_LOW,RP_MATCHES_RCVD,SPF_PASS autolearn=ham version=3.3.2 X-HELO: mail-qc0-f170.google.com Received: from mail-qc0-f170.google.com (HELO mail-qc0-f170.google.com) (209.85.216.170) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-SHA encrypted) ESMTPS; Tue, 27 May 2014 14:10:59 +0000 Received: by mail-qc0-f170.google.com with SMTP id i8so14153108qcq.15 for ; Tue, 27 May 2014 07:10:57 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=DWIRG0kem6W0oiuj6GUGF8lH6WRVUYEJhBB46p5DaUo=; b=cIDif/DLp8opMR6dtumBSF8HXl5TWdnX1TfdDoT4osprF/hy+28GuoYeQC3UfX53HV nGJw7IzSKUFEYpLVlvHzPHdXEEF0YFVwf3ZyZMNYlMK6sAYvTpWriT4SDFyW/LFJ2dSU S5Otrnqd18OMeGpF6EzHQUWI6WKa4ZETrCaVqx7KfKFqs2mJyaeRhha5+i14jSH9JGu7 okljyFqWuRJy41RbGlHjBglWxfS1njNykR2l8Ru+B7DT4czQdyuEKrdoO0gfCpNAtPTs hLaGfZOzuV82sIYFwTgehSORRHBQQ8XweeYU/x0UhODLwDfYm9vZMMufanqecBK9FaY5 4PMg== X-Gm-Message-State: ALoCoQkwqAOkv+PbX5ulHUiPb35oRdiNBiIu1j9h4b9Oy2iEpXjUccd0rjafibL6AEqFRbGtQjwQ MIME-Version: 1.0 X-Received: by 10.140.50.2 with SMTP id r2mr41718247qga.96.1401199856952; Tue, 27 May 2014 07:10:56 -0700 (PDT) Received: by 10.229.208.67 with HTTP; Tue, 27 May 2014 07:10:56 -0700 (PDT) In-Reply-To: References: <534F6901.7090700@redhat.com> Date: Tue, 27 May 2014 14:11:00 -0000 Message-ID: Subject: Re: [PATCH] Redesign jump threading profile updates From: Teresa Johnson To: Jeff Law Cc: "gcc-patches@gcc.gnu.org" , Jan Hubicka , David Li Content-Type: text/plain; charset=UTF-8 X-IsSubscribed: yes X-SW-Source: 2014-05/txt/msg02300.txt.bz2 On Thu, Apr 17, 2014 at 6:23 AM, Teresa Johnson wrote: > On Wed, Apr 16, 2014 at 10:39 PM, Jeff Law wrote: >> On 03/26/14 17:44, Teresa Johnson wrote: >>> >>> Recently I discovered that the profile updates being performed by jump >>> threading were incorrect in many cases, particularly in the case where >>> the threading path contains a joiner. Some of the duplicated >>> blocks/edges were not getting any counts, leading to incorrect >>> function splitting and other downstream optimizations, and there were >>> other insanities as well. After making a few attempts to fix the >>> handling I ended up completely redesigning the profile update code, >>> removing a few places throughout the code where it was attempting to >>> do some updates. >> >> The profile updates in that code is a mess. It's never really been looked >> at in any systematic way, what's there is ad-hoc and usually in response to >> someone mentioning the profile data was incorrectly updated. As we rely >> more and more on that data the ad-hoc updating is going to cause us more and >> more pain. >> >> So any work in this space is going to be greatly appreciated. >> >> I'll have to look at this in some detail. But I wanted you to know I was >> aware of the work and it's in my queue. > > Great, thanks for the update! I realize that it is not a trivial > change so it would take some time to get through. Hopefully it should > address the ongoing profile fixup issues. > Teresa Ping. Thanks, Teresa > >> >> Thanks! >> >> jeff > > > > -- > Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413 -- Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413