From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 28996 invoked by alias); 2 Oct 2011 10:04:39 -0000 Received: (qmail 28987 invoked by uid 22791); 2 Oct 2011 10:04:38 -0000 X-SWARE-Spam-Status: No, hits=-2.0 required=5.0 tests=AWL,BAYES_00,RP_MATCHES_RCVD,TW_CF X-Spam-Check-By: sourceware.org Received: from atrey.karlin.mff.cuni.cz (HELO atrey.karlin.mff.cuni.cz) (195.113.26.193) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sun, 02 Oct 2011 10:04:24 +0000 Received: by atrey.karlin.mff.cuni.cz (Postfix, from userid 4018) id 1CD20F0544; Sun, 2 Oct 2011 12:04:21 +0200 (CEST) Date: Sun, 02 Oct 2011 10:04:00 -0000 From: Jan Hubicka To: Xinliang David Li Cc: Jan Hubicka , Sharad Singhai , reply@codereview.appspotmail.com, gcc-patches@gcc.gnu.org Subject: Re: Disable early inlining while compiling for coverage (issue5173042) Message-ID: <20111002100419.GC19190@atrey.karlin.mff.cuni.cz> References: <20111001011237.1CF69A6832@nabu.mtv.corp.google.com> <20111001121717.GB25985@atrey.karlin.mff.cuni.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-2 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) 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: 2011-10/txt/msg00035.txt.bz2 > > Early inline can be important for FDO performance reasons -- as inline > instances get 'context' sensitive profile data. Yep, early inlining combine well with FDO. > > Inlining alone does not mess up the line info, but most > > optimizations we have in early optimization queue do. > > Inlining can do some damage too but to a less extent. For instance, > the exit block of the callee instance merged with caller's bb causing > confusion. This is still the cfgcleanup run after inlining, right? But anyway, doing coverage instrumentation before inlining (just after going to SSA) seems fine to me. We used to have cfgcleanup mode that is safe WRT line number info, not sure if it still in there. > > > > > We discussed it back when Richi implemented SSA profiling but we didn't do that > > basically due to lack of testcases.  Would be possible to take one you have > > and fill in some PRs? Those are regressions WRT pre-SSA profiling releases (I think 4.5?) > > Yes. > > Sharad, I did not see the test case attached? Please file a bug about > this. In the meantime, you can checkin the workaround to google > banches. I believe Richi opent PR back when he introduced the SSA profiling, but I don;t seem to be able to find it now. Honza