linux-mips
[Top] [All Lists]

Re: [PATCH v99,01/13] MIPS: microMIPS: Add support for microMIPS instruc

To: Kevin Cernekee <cernekee@gmail.com>
Subject: Re: [PATCH v99,01/13] MIPS: microMIPS: Add support for microMIPS instructions.
From: Ralf Baechle <ralf@linux-mips.org>
Date: Fri, 7 Dec 2012 16:24:38 +0100
Cc: "Steven J. Hill" <sjhill@mips.com>, linux-mips@linux-mips.org, "Kevin D. Kissell" <kevink@paralogos.com>
In-reply-to: <CAJiQ=7BKXMbRZqwxPnFqFS3nUuGr819zQbuhbAspOZvpCYpnFw@mail.gmail.com>
List-archive: <http://www.linux-mips.org/archives/linux-mips/>
List-help: <mailto:ecartis@linux-mips.org?Subject=help>
List-id: linux-mips <linux-mips.eddie.linux-mips.org>
List-owner: <mailto:ralf@linux-mips.org>
List-post: <mailto:linux-mips@linux-mips.org>
List-software: Ecartis version 1.0.0
List-subscribe: <mailto:ecartis@linux-mips.org?subject=subscribe%20linux-mips>
List-unsubscribe: <mailto:ecartis@linux-mips.org?subject=unsubscribe%20linux-mips>
References: <1354856737-28678-1-git-send-email-sjhill@mips.com> <1354856737-28678-2-git-send-email-sjhill@mips.com> <CAJiQ=7BKXMbRZqwxPnFqFS3nUuGr819zQbuhbAspOZvpCYpnFw@mail.gmail.com>
Sender: linux-mips-bounce@linux-mips.org
User-agent: Mutt/1.5.21 (2010-09-15)
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

<Prev in Thread] Current Thread [Next in Thread>