Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753806AbbG0Pkn (ORCPT ); Mon, 27 Jul 2015 11:40:43 -0400 Received: from mail-wi0-f175.google.com ([209.85.212.175]:38218 "EHLO mail-wi0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753512AbbG0Pkk (ORCPT ); Mon, 27 Jul 2015 11:40:40 -0400 Date: Mon, 27 Jul 2015 17:40:35 +0200 From: Ingo Molnar To: Uros Bizjak Cc: linux-kernel@vger.kernel.org, x86@kernel.org, Uros Bizjak Subject: Re: [PATCH] x86: Introduce ASM flags to bitops Message-ID: <20150727154035.GA18213@gmail.com> References: <1437869262-3211-1-git-send-email-uros_bizjak1@t-2.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1437869262-3211-1-git-send-email-uros_bizjak1@t-2.net> 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: 1702 Lines: 52 * Uros Bizjak wrote: > From: Uros Bizjak > > This patch introduces GCC ASM flags to bitops. Instead of e.g. > > 136d7: 48 0f a3 3d 00 00 00 bt %rdi,0x0(%rip) > 136de: 00 > 136df: 19 ff sbb %edi,%edi > 136e1: 85 ff test %edi,%edi > 136e3: 0f 95 c0 setne %al > > following code is generated: > > 13767: 48 0f a3 3d 00 00 00 bt %rdi,0x0(%rip) > 1376e: 00 > 1376f: 0f 92 c0 setb %al > > Similar improvement can be seen in following code: > > 7a6c: 48 0f a3 11 bt %rdx,(%rcx) > 7a70: 19 d2 sbb %edx,%edx > 7a72: 85 d2 test %edx,%edx > 7a74: 74 eb je 7a61 > > which becomes: > > 7a8c: 48 0f a3 11 bt %rdx,(%rcx) > 7a90: 73 ef jae 7a81 > > Signed-off-by: Uros Bizjak > --- > arch/x86/include/asm/bitops.h | 26 ++++++++++++++++++++++++-- > arch/x86/include/asm/percpu.h | 18 +++++++++++++++++- > arch/x86/include/asm/signal.h | 6 ++++++ > arch/x86/include/asm/sync_bitops.h | 18 ++++++++++++++++++ > 4 files changed, 65 insertions(+), 3 deletions(-) Nothing in your patch seems to be setting __GCC_ASM_FLAG_OUTPUTS__, and the patch does not seem to be mailed as part of a larger series ... So how is this supposed to work? Thanks, Ingo -- 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/