From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Fri, 07 Dec 2012 16:24:50 +0100 (CET) Received: from localhost.localdomain ([127.0.0.1]:43831 "EHLO linux-mips.org" rhost-flags-OK-OK-OK-FAIL) by eddie.linux-mips.org with ESMTP id S6823102Ab2LGPYt2knDK (ORCPT ); Fri, 7 Dec 2012 16:24:49 +0100 Received: from scotty.linux-mips.net (localhost.localdomain [127.0.0.1]) by scotty.linux-mips.net (8.14.5/8.14.4) with ESMTP id qB7FOiNF028412; Fri, 7 Dec 2012 16:24:44 +0100 Received: (from ralf@localhost) by scotty.linux-mips.net (8.14.5/8.14.5/Submit) id qB7FOckh028411; Fri, 7 Dec 2012 16:24:38 +0100 Date: Fri, 7 Dec 2012 16:24:38 +0100 From: Ralf Baechle To: Kevin Cernekee Cc: "Steven J. Hill" , linux-mips@linux-mips.org, "Kevin D. Kissell" Subject: Re: [PATCH v99,01/13] MIPS: microMIPS: Add support for microMIPS instructions. Message-ID: <20121207152438.GC25923@linux-mips.org> References: <1354856737-28678-1-git-send-email-sjhill@mips.com> <1354856737-28678-2-git-send-email-sjhill@mips.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-archive-position: 35247 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: ralf@linux-mips.org Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips Return-Path: On Thu, Dec 06, 2012 at 11:50:10PM -0800, Kevin Cernekee wrote: > Some random thoughts/nitpicks on this section: > > The microMIPS patch nearly quadruples the number of instruction > formats in the mips_instruction union, so it might be worth > considering questions like: > > 1) Is this the optimal way to represent this information, or have we > reached a point where it is worth adding more complex "infrastructure" > that would support a more compact instruction definition format? > > 2) Is there a better way to handle the LE/BE bitfield problem, than to > duplicate each of the 28+ structs? Something based on #defines, for example. Back in the dark ages I figured bitfields would be nicer way to represent instruction formats. Against the warning words of I think Kevin Kissel I went for the bitfields and this would be a good opportunity to change direction. Ralf