Re: PC in mid-pbb

[Doug Evans <dje at transmeta dot com>]

Ben Elliston writes:
 >    Yes, in several places.  The scache entries usually carry a copy (see
 >    *vpc; abuf->addr); one argument of the sem-switch entry function is
 >    the starting pc.  Your cgen semantics is supposed to be able to read
 >    the correct pc in the middle of a pbb sequence.  Perhaps you mean
 >    making a c-call -- then you should pass the pc explicitly as an
 >    argument instead of pulling it out of the sim cpu state ("hardware
 >    PC"?).
 > 
 > I'm hacking the execution loop to emit debug information at the end of every
 > cycle.  I have `vpc', but not a pc to access for part of the debug
 > information.  I'll try using one of the places you've mentioned.  Thanks,

Define "execution loop".
What kind of debug info?

The pbb (/ threaded interpreter) engine has no real loop that
you can hook into after every cycle (nor do you want one).