Christoph Hormann wrote:
> I think the work probably would have been better invested in
> implementing an internal JIT compiler using the existing hooks as
> Thorsten explained.  This would work on all x86 systems (and for Mac an
> implementation already exists).
> 
Sounded interesting. I'll have a look at that. 
Why didn't anybody put that on a publically available todo list? ;) 

> BTW your page does not say which optimizations you used for compiling
> the patched version. 
>
Well, this actually does not matter much. As pointed out on my home page, 
I used the same compiler flags for the patched and the unpatched version 
to make sure that the timings can be compared. And of course, I used the 
best ones I know. 
-O2 -ffast-math -march=athlon-xp -Wno-multichar -finline-functions 
-funit-at-a-time -fno-rtti -mfpmath=387

> To me it seems quite unlikely that you always get 
> a speedup, there is also some overhead introduced by calling an external
> library.
> 
This is correct. An external no-op function called via a pointer takes 
about 10 times as long as an internal no-op function. 
No-op function means: 
  int foo(int x)  {  return(x);  }

But we should not forget that the huge swith-case construct in the main VM 
takes some time, too. And this switch is effectively eliminated by JITC. 

Wolfgang

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