From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 31016 invoked by alias); 5 May 2011 11:03:29 -0000 Received: (qmail 31006 invoked by uid 22791); 5 May 2011 11:03:28 -0000 X-SWARE-Spam-Status: No, hits=-2.1 required=5.0 tests=AWL,BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,SPF_HELO_PASS,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from smtp-out.google.com (HELO smtp-out.google.com) (216.239.44.51) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Thu, 05 May 2011 11:03:14 +0000 Received: from wpaz5.hot.corp.google.com (wpaz5.hot.corp.google.com [172.24.198.69]) by smtp-out.google.com with ESMTP id p45B3D0i013912 for ; Thu, 5 May 2011 04:03:13 -0700 Received: from gwj16 (gwj16.prod.google.com [10.200.10.16]) by wpaz5.hot.corp.google.com with ESMTP id p45B38kw030089 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for ; Thu, 5 May 2011 04:03:12 -0700 Received: by gwj16 with SMTP id 16so718641gwj.9 for ; Thu, 05 May 2011 04:03:12 -0700 (PDT) MIME-Version: 1.0 Received: by 10.150.114.10 with SMTP id m10mr1947127ybc.412.1304593392587; Thu, 05 May 2011 04:03:12 -0700 (PDT) Received: by 10.151.41.13 with HTTP; Thu, 5 May 2011 04:03:12 -0700 (PDT) In-Reply-To: References: <20110504202659.AD3CFECC6@topo.tor.corp.google.com> Date: Thu, 05 May 2011 11:08:00 -0000 Message-ID: Subject: Re: [pph] Add streamer hook for preloading common nodes (issue4478043) From: Diego Novillo To: Richard Guenther Cc: reply@codereview.appspotmail.com, crowl@google.com, gcc-patches@gcc.gnu.org Content-Type: text/plain; charset=UTF-8 X-System-Of-Record: true X-IsSubscribed: yes 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: 2011-05/txt/msg00397.txt.bz2 On Thu, May 5, 2011 at 05:06, Richard Guenther wrote: > I think we should move away from pre-loading the streamer cache, that > has caused enough trouble when the common nodes are originating from > different Frontends and when compiling units with different flags which > happen to change those nodes (think of the hoops we jump through > to support that for -f[un]signed-char). Sure, though that's not an issue for pph. PPH images are generated and consumed by one front end. Pre-loading common nodes in C++ gives us: 1- Smaller pph images 2- Ability to do pointer comparison against common nodes. #1 saves us from saving a few hundred nodes in each pph image. But #2 is a stronger requirement. How do you think we could do #2 without pre-loading? Diego.