[Squeak-e] Programming the VM

[cg at cdegroot.com]

Colin Putney <squeak-e at lists.squeakfoundation.org> said:
>work are instances of the reified mechanisms I mentioned in my first 
>post. This would include things like object memory, interpreter, 
>compiler, compiled methods, activation stacks etc. On the hardware 
>level these would be actual CPUs, RAM etc. Then we'd have the 
>abstractions of these provided by the OS: processes, virtual memory 
>etc. Then we have the Squeak-E executable, with *its* abstractions, the 
>things I was referring to originally: Class, Compiler, Processor, 
>Display, thisContext, MethodDictionary, etc.
>
Ok, we're talking about Squeak-E level, so Class, Compiler, Processor,
Display, WorldMorph, ... are the things to be virtualized. Basically 
stuff in the Smalltalk dictionary...

>At deeper levels of virtualization, it looks like we'd need separate 
>reifications of these abstractions, that are limited in scope to the 
>virtualization level that we're dealing with. These would effectively 
>be capabilities for manipulating the virtualization subtree rooted at 
>that (virtual) machine.
>
I think Mark's idea is that you only need them as far as you need to
modify them (restrict them more) in 'deeper levels'. If you make sure
that, no matter at what level, you never can peek a level up, then most
of the time you can just pass on your own environment with just a couple
of tweaks. By making sure you can do this, you avoid performance hits at
deeper levels.

-- 
Cees de Groot               http://www.cdegroot.com     <cg at cdegroot.com>
GnuPG 1024D/E0989E8B 0016 F679 F38D 5946 4ECD  1986 F303 937F E098 9E8B
Cogito ergo evigilo