[pypy-dev] pypy for typed languages?

[Armin Rigo]

Hi Paolo,

On Mon, Mar 23, 2009 at 11:46:29AM +0100, Paolo Giarrusso wrote:
> I was thinking about the method cache in the interpreter; I'm not yet
> familiar with the approaches you used for JIT compilation (neither the
> one of PyPy 1.0 nor the one being prototyped right now), but I know
> the general purpose "get a JIT from an interpreter", and I thought
> that having a matching behaviour implied using the same lookup
> algorithm in JITted code. I understand that's no more true, with the
> ideas of trace-based JITs.

Ah, sorry.  I may have misread your original post.  The fact is that
both the PyPy 1.0 JIT and the current prototype JIT (and all other
prototypes inbetween) are similar, in that they are derived
automatically from the interpreter.  If this interpreter happens to
contain a hash table lookup, as the Python interpreter of PyPy
optionally does, then the JIT will contain it too.  So we are left with
experimenting with which interpreter features are useful for the JIT
too, and which ones give bad results.  This experimentation is both easy
and not quite doable right now because we are still developping the JIT
generation basics.


A bientot,

Armin.