From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leo Famulari Subject: Re: [PATCH 2/2] gnu: icecat: Use libjpeg-turbo instead of bundled libjpeg. Date: Sun, 27 Nov 2016 17:43:19 -0500 Message-ID: <20161127224319.GA1254@jasmine> References: <20161127201707.3789-1-me@tobias.gr> <20161127201707.3789-2-me@tobias.gr> <20161127205618.GC27187@jasmine> <20161127214119.GB30774@jasmine> <87wpfotwwk.fsf@kirby.i-did-not-set--mail-host-address--so-tickle-me> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="h31gzZEtNLTqOjlF" Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:56187) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cB8AS-0004dn-E9 for guix-devel@gnu.org; Sun, 27 Nov 2016 17:43:29 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cB8AN-0001t3-IQ for guix-devel@gnu.org; Sun, 27 Nov 2016 17:43:28 -0500 Received: from out5-smtp.messagingengine.com ([66.111.4.29]:35335) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cB8AN-0001su-EG for guix-devel@gnu.org; Sun, 27 Nov 2016 17:43:23 -0500 Content-Disposition: inline In-Reply-To: <87wpfotwwk.fsf@kirby.i-did-not-set--mail-host-address--so-tickle-me> List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: "Guix-devel" To: Marius Bakke Cc: guix-devel@gnu.org --h31gzZEtNLTqOjlF Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun, Nov 27, 2016 at 10:50:35PM +0100, Marius Bakke wrote: > Leo Famulari writes: > > I'm not sure, but the comment seems to indicate that we don't want to > > use it: > > > > ;; According to > > ;; http://sourceforge.net/projects/libjpeg-turbo/ , > > ;; "libjpeg-turbo is a derivative of libjpeg that > > ;; uses MMX, SSE, SSE2, and NEON SIMD instructions > > ;; to accelerate baseline JPEG compression/ > > ;; decompression", so we had better not use it >=20 > SSE is pentium III, and SSE2 was introduced in Pentium IV. MMX is even > older. Are we really committed to supporting 15+ year old hardware? See this earlier thread: http://lists.gnu.org/archive/html/guix-devel/2016-07/msg01534.html I think it's fine to use libjpeg-turbo if it can run on those older processors, or if we decide to drop support for them. > The NEON SIMD instruction seems to be ARM-specific and is available at > least on Cortex A8, which is an ARMv7 design. The extremely popular Cortex A7 [0] also has NEON SIMD. [0] Allwinner A20 --h31gzZEtNLTqOjlF Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEsFFZSPHn08G5gDigJkb6MLrKfwgFAlg7YYMACgkQJkb6MLrK fwhW0A//ctHqtf7gS7B1myUikJDZq4C9woID2mpDtZxnDWt0N4zkRy7BV3dcfuLY 1VcPCm1hPG6rmbxTi7+1vnGfknFHBrHk5oUmn4jSiO/DqGPUG+YJ1rlBEDgZhzDz g1Fd5ehg5bpNO/ZpWAQJwqPPJd3fF6YIn+liJVZO27uDETtsQmfnY5fpEKlTp2ih iNbQnFJM3kp3sUHgzerbQtm7VaCbnSeR5GwFZqKe7cYnum65Q9jPeFK/CXnTrmqD cyzuDKgcmCD+Hv3eg118lA4UoJU4uGU2rc2oADpibmmDCMnEMSkJKWxR4z03alg9 xSS8YDVchFXuuJHQW4YDstDH4kbW66Na0+cZpdokMNfkBKDM2W2HN3CYNDucrvX7 jtPzXhdHXrabIjJRNs+uGxLHs8VGwHdSOt2INdRUWkrIdBE3zF861tUQ9WHh5bfF v6iVcg7Vgu9pTpBVOAuFbJihJMvouLS6lgtj7FkYrG+aQNtFMYgxfTNltjgHzETs Hk/FVbLMkZP2PjZx9ocaZGyjJxHTlQYAf5GGwqPO2hIPpvYQJLavPFUqFSbh9wS8 I8T5Mw1yYIds233V8Zmmi1V9n3Olg6RnmBFCn3R0zQLFeq2RPOrJwmzFwha1mm6z zFaAfTsRbFEFc8m+wvU7MNgS0VkTY/oR78d7LH9+p6OQdaodWb0= =746A -----END PGP SIGNATURE----- --h31gzZEtNLTqOjlF--