[pypy-dev] Re: Greetings

[Jonathan David Riehl]

On Wed, 2 Jul 2003, holger krekel wrote:

> In this doc-directory (http://codespeak.net/pypy/doc) you'll also find some
> unsorted documentation which might help in understanding what we have been
> doing this year.

Still trying to decode the docs, but the RPython stuff is starting to look
familiar (I was going to something similar).  I know Chris mentioned
working on a pure-Python compiler (one that didn't use sre), but if anyone
has a good starting point in mind, please let me know.

> Also, at least i am quite interested to get to know what you have done
> or what you found out about Python-to-C translators.

I was building dataflow models of Python, which I thought might be useful
for type inference.  There was a paper on PyFront published in the IPC 8
proceedings:

http://www.foretec.com/python/workshops/1998-11/proceedings/papers/riehl/riehl.html

I actually didn't bother to schedule the DAG's (I didn't know anything
about that topic at the time) and ended up emitting the basic blocks by
simply inlining calls to the Python API.  One thing about the dataflow
representation that I liked was that it made constant folding a snap (by
virtue of its construction, it was already done for you) and I think I
could have easily done common subexpression elimination.  The one bad
thing about the representation was it's functional representation
(iterative loops would translate to recursive functions), since I still
don't know much about elimination of recursion on the back end.

-Jon