Re: WIP: Register doco

Andrew Cagney
2002-07-24T15:35:47Z

> If this section needs an example then (given MarkK's observation about
>> the i387) then either d10v's two stack pointers or the SH's bank
>> registers. Neither of these are especially complicated.
>
>
> But... but the IA-32's FP and MMX hair is, like, the canonical
> motivation for the cooked/raw distinction. You've said repeatedly
> that a GDB developer needs to understand this distinction. That makes
> it a *good* example, right? I think it's one of the best ---
> especially since it's something familiar to a lot more people than the
> d10v and the SH.

The original motivation for this model was work by David Taylor for an
architecture that dual ported all of memory (memory == register).
Additional motivations came from SH4 (sh5 proved the model), d10v and
MIPS. The i386 was but a blip on the horizon.

Given we're struggling amonst ourselves with the IA-32 I think that
suggests it is a very poor choice for an example. Especially given
there are better cleaner examples to be had using other familar
architectures. I would assume this is why people like H&P chose DLX
when describing CPU architectures.

enjoy,
Andrew