Re: [Sablevm-user] SableVM question

[Marcel A. <ma...@ca...>]

On Tue, Aug 29, 2000 at 11:06:52AM -0400, Etienne M. Gagnon wrote:
> meg.com> <200...@ri...> <39A...@j-...> <200...@ar...>
> Content-Type: text/plain; charset=us-ascii
> Content-Transfer-Encoding: 7bit
> Sender: uucp <uu...@ar...>
> 
> Marcel Ammerlaan wrote:
> > Ok. I've retested it and the results are much better now for the goto case
> > (around 3 times faster) with a real-life example (e.g. newtest1 && newtest2).
> 
> Ah!  This is much more in line with the material that can be found on
> "threaded interpretation" the literature.  
> 
> > I will get my own VM up & running again and use that as a testbed instead
> > of simple programs so the compiler won't fool me again:)
> > 
> > I hate assembly and usually avoid it but in a case like this I should have
> > checked what GCC did to the code...
> > 
> > > I might still be wrong, so please continue testing and keep us updated
> > > on your findings.
> > 
> > I will (for now I'm focussing on the pre-interpretation bit as I've got
> > better results when skipping this part and using a lookup table. I will
> > investigate:)
> 
> Do not forget that the pre-interpretation phase is a linear phase. 
> While running a real interpreter, you usually have many loops and
> recursion that will make the pre-interpretation phase overhead pretty
> insignificant.  This phase does nothing as complex as a non-naive JIT
> would do.

I'm aware of that, I've measured running the code about 40.000 times (versus
translation once), the difference between a real VM and the test code is 
the static nature of the list of instructions. I let you know what the
results are (tonight or tomorrow) 

Marcel Ammerlaan