[Vm-dev] Switching an active context in Cog

Hello,

i want to adopt an image-side scheduling for Cog and since everything which sounds like 'Process' will be wiped out from VM, i need a way to cleanly switch the active context to a new one.

I think that as a guide for implementation could be taken CoInterpreter>>transferTo: newProc from: sourceCode

but i am a bit confused by following:

self push: instructionPointer. ...(switching code)... instructionPointer := self popStack.

does that means, that instruction pointer is always stored in last stack position instead of some fixed slot of context?