[pypy-dev] Pypy custom interpreter JIT question

[Dima Tisnek]

On 31 March 2011 05:33, Antonio Cuni <anto.cuni at gmail.com> wrote:
> On 31/03/11 14:28, Andrew Brown wrote:
>> In any case, I'm satisfied with the speed. It's still beaten by a BF to C
>> translator combined with gcc -O2 though, that'd be a tough case to beat. =)

What if bf code was really really large?

bf to c then gcc could take a hit as it might thrash cpu cache, as
single pass gcc doesn't know what a given program would actually do at
runtime.

jit'd rpy would only have 1 hotspot, always in cache, and might be a
little smarter too.

I suppose it's hard to beat 2-pass (profile driven optimized) compiled c though.

>
> what happens if you combine the BF to C with gcc -O0 or -O1?
>
> Anyway, I think that if you feel like writing a post explaining your
> experience with using pypy and its jit for writing an interpreter, we could
> publish it on our blog.  I suppose it would be useful/interesting for other
> people as well.
>
> What do the others think?

I think it can be a great example. It's very educational ;-)

It could go into official docs/howto too.