[rescue] SS10/20 death

[Francisco Javier Mesa-Martinez]

On Tue, 5 Feb 2002 dave at cca.org wrote:

> mcguire at neurotica.com writes:
> 
> >On February 5, dave at cca.org wrote:
> >> Do you think the SPARC's register windows were a good idea? (For a
> >> general purpose unix box, that is.)
> 
> >  Tremendously good, yes.
> 
> That's good to hear. I thought the extra work of spilling to the stack
> and especially the added complexity of context switches might negate
> the wins, at least for general unix/c codes. It kind of looks more like
> a custom OS embedded app type design.
> 
> Have you ever enocuntered anyone using the windows for anything
> other than function calls?
> 
> SPARC's register windows always seemed like one of the weird &
> abandoned experiments in the crazy early days of the "RISC hype" before
> a few years of actually producing machines made it obvious that the
> wins of "RISC" amounted to: load/store arch & fixed length instructions.
> (Which is why I still think Cray's machines qualify, all the way back
> to the CDC-6600.)
> 

Theoretically the Register windows are transparent to the programmer, and
the assembler... so the machine will use them whether you want them or
not. And I do not understand why Register windows will add complexity to
context switches, if anything they aleviate the cost of context switches.
I simply think of the register windows as just extra registers...