Re: Cyrix M2

Raul Miller (rdm@test.legislate.com)
Thu, 24 Apr 1997 10:44:58 -0400

Mike Jagdis wrote:
> >
> > (Cyrix had to use FP registers for MMX to be at all compatible
> > with Intel. I don't think they liked having to do it :-). Intel
> > did it to save the cost of engineering their silicon to hold a
> > few more registers.)

On Apr 24, Joerg Pommnitz wrote
> AFAIK the main reason was, not to break existing operating systems.
> These OS don't know how to save MMX registers on task switchs. I
> don't see how Cyrix would have solved this problem.

Wouldn't be hard to put in a state bit which defaults to MMX overlays
FP but could be set to MMX independent of FP. [Presuming you wanted
to invest in the real estate for the separate register set.]

-- 
Raul