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Re: How to clean up i386 machine description?
- To: howell at cs dot stanford dot edu, law at cygnus dot com
- Subject: Re: How to clean up i386 machine description?
- From: mrs at wrs dot com (Mike Stump)
- Date: Thu, 19 Nov 1998 16:38:21 -0800
- Cc: amylaar at cygnus dot co dot uk, egcs at cygnus dot com, hubicka at horac dot ta dot jcu dot cz, pcg at goof dot com, rth at cygnus dot com
> Date: Wed, 18 Nov 1998 12:26:42 -0700
> From: Jeffrey A Law <law@cygnus.com>
> In message <199811122144.NAA19144@Sunburn.Stanford.EDU>you write:
> > I don't think the goal is to have a clean-looking machine description;
> > the x86 architecture is itself too messy for that.
> I disagree. It *is* one of the goals. Messy machine descriptions lead to
> bugs and long term maintenance problems. We should be addressing those
> issues as well as the performance issues.
I agree with Jeff. If one finds oneself doing what they consider
messy, then try and envision a new way of describing the problem in
the md and lets talk about it. We may not get it implemented right
away, but knowing how to improve the description processor (if it is a
recurring theme present in md files) so support more natural
descriptions and even writting that down as a TODO item is a whole lot
better than just ignoring the elephant. Others might find delight in
implementing what others want, but can't afford to write it.
I seem to recall reading years ago that someone (rms) wanted the
addressing modes mdized, instead of the #define they are today. This
is an example of the type of thing that might help make things more
regular/descriptive and nice looking.