From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46782) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e6H52-0004a9-0U for qemu-devel@nongnu.org; Sun, 22 Oct 2017 10:18:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e6H4x-0001NC-2Y for qemu-devel@nongnu.org; Sun, 22 Oct 2017 10:18:19 -0400 Received: from mail.uni-paderborn.de ([131.234.142.9]:35436) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e6H4w-0001Mo-O3 for qemu-devel@nongnu.org; Sun, 22 Oct 2017 10:18:15 -0400 References: <6968797c-f64c-69ff-2fa6-79c4fb3440c9@mail.uni-paderborn.de> <20171021064444.GJ30459@redhat.com> From: Bastian Koppelmann Message-ID: <978b4e0a-8a9c-68e9-5c3d-a1cca51b947c@mail.uni-paderborn.de> Date: Sun, 22 Oct 2017 15:22:49 +0200 MIME-Version: 1.0 In-Reply-To: <20171021064444.GJ30459@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [sw-dev] [RFC] RISC-V Decoder generator List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Richard W.M. Jones" Cc: RISC-V SW Dev , QEMU Developers Hi Richard, On 10/21/2017 08:44 AM, Richard W.M. Jones wrote: > On Fri, Oct 20, 2017 at 03:46:54PM +0200, Bastian Koppelmann wrote: >> I asked you for feedback some while ago regarding a modular RISC-V QEMU >> target (see discussion [1]). I tried getting it to work with the good >> old C preprocessor and quickly realized that it is too limiting. Instead >> I created a data-driven decoder generator written in python (see the >> code on github [2]) using YAML as a description language. >> >> I'd like to get some feedback whether this is acceptable to be >> upstreamed to QEMU or if you have any suggestions for improvements. >> Right now only RV32I instruction are implemented in this scheme. > > My suggestion would be to reimplement (part of) the s390x decoder > using this scheme. That would give us a direct comparison of how your > scheme is better or worse than the existing macros. Yeah that would be a great test. However I'm not sure if it's worth the effort. AFAIK s390x will not be extended with new instructions, so there is no need for a new scheme unless it helps making the code better maintainable. But that's up to the s390x maintainers. > > Will you be at the KVM Forum next week? No, sorry. I'm at the verge of graduating from University, so my time is very limited right now :( Cheers, Bastian