Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755290Ab3HEUmy (ORCPT ); Mon, 5 Aug 2013 16:42:54 -0400 Received: from mail-yh0-f51.google.com ([209.85.213.51]:46463 "EHLO mail-yh0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755232Ab3HEUms (ORCPT ); Mon, 5 Aug 2013 16:42:48 -0400 Message-ID: <52000C76.3060601@twiddle.net> Date: Mon, 05 Aug 2013 10:35:02 -1000 From: Richard Henderson User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130625 Thunderbird/17.0.7 MIME-Version: 1.0 To: Jason Baron CC: Marek Polacek , Linus Torvalds , Steven Rostedt , LKML , gcc , Ingo Molnar , Mathieu Desnoyers , "H. Peter Anvin" , Thomas Gleixner , David Daney , Behan Webster , Peter Zijlstra , Herbert Xu Subject: Re: [RFC] gcc feature request: Moving blocks into sections References: <1375721715.22073.80.camel@gandalf.local.home> <1375725328.22073.101.camel@gandalf.local.home> <20130805194009.GZ17022@redhat.com> <520003B8.8090503@akamai.com> In-Reply-To: <520003B8.8090503@akamai.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1644 Lines: 43 On 08/05/2013 09:57 AM, Jason Baron wrote: > On 08/05/2013 03:40 PM, Marek Polacek wrote: >> On Mon, Aug 05, 2013 at 11:34:55AM -0700, Linus Torvalds wrote: >>> On Mon, Aug 5, 2013 at 11:24 AM, Linus Torvalds >>> wrote: >>>> Ugh. I can see the attraction of your section thing for that case, I >>>> just get the feeling that we should be able to do better somehow. >>> Hmm.. Quite frankly, Steven, for your use case I think you actually >>> want the C goto *labels* associated with a section. Which sounds like >>> it might be a cleaner syntax than making it about the basic block >>> anyway. >> FWIW, we also support hot/cold attributes for labels, thus e.g. >> >> if (bar ()) >> goto A; >> /* ... */ >> A: __attribute__((cold)) >> /* ... */ >> >> I don't know whether that might be useful for what you want or not though... >> >> Marek >> > > It certainly would be. > > That was how I wanted to the 'static_key' stuff to work, but unfortunately the > last time I tried it, it didn't move the text out-of-line any further than it > was already doing. Would that be expected? The change for us, if it worked > would be quite simple. Something like: It is expected. One must use -freorder-blocks-and-partition, and use real profile feedback to get blocks moved completely out-of-line. Whether that's a sensible default or not is debatable. r~ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/