From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BB8A71FF7D7; Wed, 12 Feb 2025 20:10:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739391024; cv=none; b=SIee9Nb4DY9JIMrhNe2gqjoD7B2URn1NH60AyJQrULqdiJDH3eVIxPdwMwRY7n8oaVpw23tWSYFh8QdzRq/4+HMqX+mvSNePARHqeIc/49YIp3FdK1Q9WQn0xX7V447aBBXBxV+Xcd/0VAZWSg4TVlA2lirIZp0hOGgrRXml0K0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739391024; c=relaxed/simple; bh=MnKhK0zOJBzcyNRgjiIUC2lRoRSPV9C2Ro3ePenE6bk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QdpOYYEe5E9R3b4hJcjbL3oESTObo0+b/PYPSUT4d9qgZ7WI6Zq9qgUW3G7ll3kVAXu/OBdKedtgswPKbGXc87zu+FMefN+sdvrZ6X8Ym2oDtk8cEoUcszfI5s8/4Y0MuJOImzxsa/gyagmi59JdjYqtDUwwBpJMGlgeFxhmdbU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mkdxz7t/; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mkdxz7t/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0038AC4CEDF; Wed, 12 Feb 2025 20:10:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1739391024; bh=MnKhK0zOJBzcyNRgjiIUC2lRoRSPV9C2Ro3ePenE6bk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=mkdxz7t/rLARM5ml+gzAnpeA3F/KcTQ2v9DqvEEdbHyf72+3F6QaGzDtjo+Uxg/px WGL4Rq+XIAhOJXJg+J3pD6BGhPlP40EDpiWpLe+0XXrDfxQOGW+2yXrXzqkGK6blhn vG4/7sKVlOMo+1uTmM4pd8snhgt9lXmiBQG6W9+MIgFMtppikqxJOmAp/+3FLYFBzm mCvFsmWBqvqCM2oxfnNYyymaCkvrcACrTfzFc9a7/T5y5HfqtAFvlR/shNPx/g5219 3+wcDwGV5xLSQkPdh3NF0zDCtvrU1naDMKPCc5ItvCPMvWWsJTHw8jNgSDaxNf7Y48 /LUdELGo1ageQ== Date: Wed, 12 Feb 2025 12:10:22 -0800 From: Eric Biggers To: linux-kernel@vger.kernel.org Cc: linux-crypto@vger.kernel.org, Ard Biesheuvel , x86@kernel.org Subject: Re: [PATCH] x86/crc32: improve crc32c_arch() code generation with clang Message-ID: <20250212201022.GB128826@sol.localdomain> References: <20250210210741.471725-1-ebiggers@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250210210741.471725-1-ebiggers@kernel.org> On Mon, Feb 10, 2025 at 01:07:41PM -0800, Eric Biggers wrote: > From: Eric Biggers > > crc32c_arch() is affected by > https://github.com/llvm/llvm-project/issues/20571 where clang > unnecessarily spills the inputs to "rm"-constrained operands to the > stack. Replace "rm" with ASM_INPUT_RM which partially works around this > by expanding to "r" when the compiler is clang. This results in better > code generation with clang, though still not optimal. > > Signed-off-by: Eric Biggers > --- > > This applies to > https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux.git/log/?h=crc-next Applied to crc-next. - Eric