On 21-Jul-08, at 7:13 AM, Eliot Miranda wrote:
>
> The primitive doesn't set any bits in the context.  It merely fails,  
> ad the method is activated exactly as if on:do: did not have a  
> primitive.
>
> The VM finds activations of on:do: by examining the header of each  
> context's compiled method (no bits are set in the context).  Methods  
> with primitives have the primitive number stored in a field in the  
> method header.
[snip]
> BTW, this is a really nice implementation by Andreas and Dan.  In VW  
> there are bits in the method header because primitives are not  
> stored in the method header but in the bytecode.  But this means we  
> need a little bit more machinery.  Using the primitive field is very  
> simple and just as effective
Actually I'm pretty sure that was me. Certainly I did all the  
exception handling stuff in the VM and old email implies we came up  
with using a prim number as a flag in order to make it simple to both  
interpret and support the old J3 attempt with minimal changes. This  
was  all done back in august 200 or so. There was of course  
considerable back and forth about various details, lasting for several  
months IIRC.

tim
--
tim Rowledge; tim at rowledge.org; http://www.rowledge.org/tim
Useful random insult:- One chicken short of a henhouse.