> We're not forcing all cpu models to support predication, only have to a
> function allows the cpu to understand if an instruction didn't execute
> because it was predicated. If the CPU chooses to do nothing with that, as
> the simple cpus do, then so be it.
>
> It's like saying that we shouldn't have a micro-pc function because Alpha
> doesn't have any micro-coded instructions or we shouldn't have a NextNPC
> because only sparc has delay slots.

I think we're bikeshedding now.  Remember that our CPU models are a
superset of what is needed.  That's why you put microcode support into
the models.  Similarly, I'd expect predication to need to be there
too.  Of course there is the danger of such a superset becoming
unwieldy, but when there is no clear right answer, or when it is just
a differing of opinion, I think we should try to err on the side of
allowing the code to be committed.  If things truly do become a mess,
then there is always the opportunity to refactor and improve things
later.  We also have to be careful not to burden a committer with our
wishes.  I may wish that the build system were better, but I shouldn't
stop some from extending the existing one if I'm not actually going to
replace it soon.

  Nate
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