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 9B6E843AD9 for ; Fri, 10 May 2024 20:43:38 +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=1715373818; cv=none; b=aLEzgyNGNTeSLerAj6XmGg8cjp660XhAhAYt872fjcvQQpNx/k5kpodTBrQaldwgu30Z9j5XQMRIWzUW/uDcd+J4Wm8SxuT8Gwil5aFG7llZ58jy6Q4D2/e/9D8d+pvtDg9MnBB/+rW4QON60baJoKDqNY5Uz300Vh6pgUe3/ec= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715373818; c=relaxed/simple; bh=V1weiyqYUi8cf0/ypiHaTqUR1iBXGA2Jxo6KOzagAx8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=sWAfw+H7YT+efQ6N23R+h5IJetrWaJXVmZPEpUyp0SDBo6ahqosXtUwZhOGk1zVTTX31DWRjUiZtxO8c024rFzn7l2gVoZhDW4t8BNgFY/G0wk51W2iauxOzjuwahmDLxYnUWfGLaNuIapHe/i/TleLx8DljwJMnl9s/axglcSA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZXZkQa3p; 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="ZXZkQa3p" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 824FFC32781; Fri, 10 May 2024 20:43:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1715373818; bh=V1weiyqYUi8cf0/ypiHaTqUR1iBXGA2Jxo6KOzagAx8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZXZkQa3pJnj42KiEXIR1BP+TayP4gESPmBa6+RH8LUZrZlcAKDsgA8sI5IK3F13vB +ibcG3vY+8oNiJJJOu+DsPmfvRnKbaL0pf4Fxa9Yi6k89Tnn+zOAAoIDdmc5wIwS0E jmh6xA+pLxIcHfDHR4qZsqnL5sccoupfGTEJwaqq920X/OeZJtrYU/BS8YwgHmSN9q JQWYjqzbAFrgImdxj7kaIJmGMd7LAIJD4ET03kSwowkAGljZorS8YvpKF2Sj2GordG jePeLEMLyNSi4szrut/FoCSe70RPX79lSrYdHgnfMGHzPKwluHdRAS9qhVE/yM2gFu 03vgHJeLDBY3Q== Date: Fri, 10 May 2024 21:43:33 +0100 From: Conor Dooley To: Charlie Jenkins Cc: Paul Walmsley , Palmer Dabbelt , Albert Ou , Conor Dooley , Song Liu , Xi Wang , =?iso-8859-1?Q?Bj=F6rn_T=F6pel?= , =?iso-8859-1?Q?Cl=E9ment_L=E9ger?= , Jessica Clarke , Andy Chiu , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/8] riscv: Add PLATFORM_MAY_SUPPORT_RISCV_ISA_V Kconfig option Message-ID: <20240510-earthly-regress-7a8c8dba55db@spud> References: <20240507-compile_kernel_with_extensions-v2-0-722c21c328c6@rivosinc.com> <20240507-compile_kernel_with_extensions-v2-2-722c21c328c6@rivosinc.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="kt7YioCjm2Pco75f" Content-Disposition: inline In-Reply-To: <20240507-compile_kernel_with_extensions-v2-2-722c21c328c6@rivosinc.com> --kt7YioCjm2Pco75f Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hey Charlie, On Tue, May 07, 2024 at 06:36:28PM -0700, Charlie Jenkins wrote: > Current versions of the kernel add "v" to the march and then immeidately > filter it out such that "v" is not passed to CFLAGS. Instead of doing > this filtering, code blocks in the kernel that want to use vector > assembly have been changed to locally enable vector (using ".option > arch, +v"). Other content in the series aside, since this is a change that could be made independently of the main series objectives, I figured it was worth pointing out that this is not a change without downsides: I think that it would drop support for vector with most versions of LLVM as .option arch support there is much more recent thing than it is for gcc. Off the top of my head I don't know exactly the versions involved, but it is something like LLVM-14 supports vector but only LLVM-17 and later supports .option arch. Thanks, Conor. --kt7YioCjm2Pco75f Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHQEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZj6G9QAKCRB4tDGHoIJi 0q+gAPjjKuRZgtdpysJjkfjOXgAbIViLfJa9YW6kDhN9A8nZAP9+kEU1aZXKxvFD 4McVJZQgAsM/xY3ZI7ahJNfgyKE5Bg== =hfje -----END PGP SIGNATURE----- --kt7YioCjm2Pco75f--