hilpert at cs.ubc.ca
Tue Oct 2 18:35:36 CDT 2007
Chuck Guzis wrote:
> On 2 Oct 2007 at 15:33, Brent Hilpert wrote:
> > Though IIRC, with a well-designed stack management policy, the register
> > frames could overlap, so as long as one didn't use the registers in
> > overlapping memory you were fine. You were not obligated to grab a fresh 16
> > words of memory on every function call. Equivalent in more conventional archs
> > to deciding how many machine registers you're going to save based on usage on
> > a function call rather than saving them all without question.
> Agreed. But 128 words still doesn't leave much room for variables
> beyond those that can be stored in the registers of each frame.
> There's a comment on one of the 99/4A sites that 1,024 bytes of RAM
> were originally planned, which is more reasonable. I doubt that TI
> saved very much by using the 256 byte part.
Oh, agreed too. I'm sticking up for the 990/9900 architecture, but in no way
trying to defend the 99/4 design. Based on what others are describing the
latter was amazingly limiting.
I guess home computing got tossed over to the consumer products division at
TI, which always seemed to have a bottom-of-the-line/low-end approach to
things, too bad they didn't find some middle ground between that and their
higher-end commercial/military stuff.
More information about the cctech