From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:37045) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gy3L0-0002bl-F0 for qemu-devel@nongnu.org; Sun, 24 Feb 2019 18:37:39 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gy3Kz-0003Ly-CU for qemu-devel@nongnu.org; Sun, 24 Feb 2019 18:37:38 -0500 Received: from ozlabs.org ([203.11.71.1]:47975) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gy3Kw-0003It-Le for qemu-devel@nongnu.org; Sun, 24 Feb 2019 18:37:37 -0500 Date: Mon, 25 Feb 2019 10:31:42 +1100 From: David Gibson Message-ID: <20190224233142.GC7668@umbus.fritz.box> References: <20190222055950.17403-1-richard.henderson@linaro.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="IpbVkmxF4tDyP/Kb" Content-Disposition: inline In-Reply-To: Subject: Re: [Qemu-devel] [PATCH] tcg/ppc: Add vector opcodes List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Mark Cave-Ayland Cc: Richard Henderson , qemu-devel@nongnu.org --IpbVkmxF4tDyP/Kb Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Feb 22, 2019 at 05:13:37PM +0000, Mark Cave-Ayland wrote: > On 22/02/2019 05:59, Richard Henderson wrote: >=20 > > This requires VSX, not just Altivec, so Power7 or later. > >=20 > > Signed-off-by: Richard Henderson > > --- > >=20 > > At present there are no tunables that can avoid the 64-bit element > > load/store requirement. As with requiring AVX1 for x86 hosts, I'm > > not sure it's worth inventing such a tunable for pre-power7 hosts. > >=20 > > Tested vs aarch64 risu test cases. It's probably worth testing > > this vs Mark's target/ppc conversion. >=20 > Oooh this looks really exciting! However... I only have a G4 Mac Mini aro= und that I > use for testing which is Altivec-only :( Is it much work to support > non-VSX hosts? I have access to POWER8 and POWER9 machines, but I haven't worked with RISU before. If you can give me a straightforward recipe I can try running the tests. >=20 > This leads me to a related point that came up when Howard and I were test= ing the PPC > vector patches - how do we know at runtime which optimisations were being= used, e.g. > what is the value of have_avx2 on a particular CPU running QEMU? >=20 > Under Linux this isn't too bad since you can just do "cat /proc/cpuinfo |= grep avx2" > but it becomes more tricky when getting bug reports from Windows users wh= o aren't > particularly technical... >=20 >=20 > ATB, >=20 > Mark. >=20 --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --IpbVkmxF4tDyP/Kb Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEdfRlhq5hpmzETofcbDjKyiDZs5IFAlxzKV4ACgkQbDjKyiDZ s5K3gg/8DPYs0hcU9q1zN4q+eroCfmI5zlHQnE0PpoWFHMyGMzAXE2u6MuaveOEn Q996j7BcM03/biG0JBti5YnpSX4UaEx6LBbnlxyswW7hg0NXRXN1Pq1SKezl0vmJ mO/b0tWoUrflyBUjH5hWN91EgCxvYMJebLhOl3OQBBnNShP2aB+vpYsJa7TNApFA X2HTT2Rd/BgyfIzeyRJcETLvg6pf/a6Pro7PHhwdm0Xe4o/ZcaEhW7r6dhS20UHP 4JknhDz3TllwHhS3/duPH0aBqQ+MBR6w5AA2PeqcIGq03HIMifdiEV4235WWPma1 ottOaa0dHnStyvAvVChCZUQXV2t8jOMd6/H3JfUYzA/hxZE1eCJQUKq4hqTfmejG 9n0QA+c/0lO/1PHh9dc8Y/HT1+h8zH5Lq/MgKOiHPrfed9+cuAsUIt5aDZmkvcKQ PsK02ATMdsq0/6HckrMk853Zb6e4mtakLM/Q0wvyDD30F9nfbBClq2yB8npKxdVU /KklX9bwOzsu7I8UAAuAJy4gJ2bx9YvR8DxsbFZB86cKopupVAAueGUxoTdu9GYg ZWoYoHzUixoeIn3m36F9jwTIC3vx3OkwbNPe7Gg6LaObASMPT/Ecn6MQs97YSJyQ vH1r8waDZ/vhkt9hWshqXDjQK+K1Er0c1fGsudQ1ZSaqymaOizQ= =Gzmm -----END PGP SIGNATURE----- --IpbVkmxF4tDyP/Kb--