[pypy-dev] Annotating space status

[Guido van Rossum]

> For the problem with W_ConstantIterator I'm a bit confused. Where is
> the code that allows more than just one frame to be saved for the
> same bytecode position? In other words I don't understand how this
> code can unroll the loops in the helpers.

I have a feeling that the real problem here may be that the value
stack isn't properly cloned, which means that the frames stored in
knownframes will share their objects with the frame being modified as
part of the current frame evaluation.  I'd bet that if you properly
clone the value stack using clonecells(), Samuele's hack (adding a
'changed' flag to the W_ConstantIterator class) would no longer be
necessary.

Wishing I had time to code this up,

--Guido van Rossum (home page: http://www.python.org/~guido/)