Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752283AbbEAQeZ (ORCPT ); Fri, 1 May 2015 12:34:25 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55738 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751122AbbEAQeY (ORCPT ); Fri, 1 May 2015 12:34:24 -0400 Date: Fri, 1 May 2015 18:33:29 +0200 From: Jakub Jelinek To: Linus Torvalds , Richard Henderson , Vladimir Makarov Cc: Peter Zijlstra , Ingo Molnar , "H. Peter Anvin" , Thomas Gleixner , Linux Kernel Mailing List , Borislav Petkov Subject: Re: [PATCH] x86: Optimize variable_test_bit() Message-ID: <20150501163329.GU1751@tucnak.redhat.com> Reply-To: Jakub Jelinek References: <20150501151630.GH5029@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 822 Lines: 17 On Fri, May 01, 2015 at 09:03:32AM -0700, Linus Torvalds wrote: > > PPS. Jakub, I see gcc5.1 still hasn't got output operands for asm goto; > > is this something we can get 'fixed' ? CCing Richard as author of asm goto and Vlad as register allocator maintainer. There are a few enhancement requests to support this, like http://gcc.gnu.org/PR59615 and http://gcc.gnu.org/PR52381 , but indeed the reason why no outputs are allowed is the register allocation issue. Don't know if LRA would be better suited to handle that case, but it would indeed be pretty hard. Jakub -- 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/