Stack Machine to Register Machine

[mcp]

Not sure I really understand your question.
It seems you're asking on how to reconstruct the original register based instructions? That is not possible, as that information is destroyed.

For example, given that stack based VM, you cannot distinguish

mov eax,ebx
mov ecx,eax
mov edx,ecx

from

mov ebx,eax
mov edx,ebx
mov ecx,edx

What you can do however, is what in compiler construction is called "register allocation". It basically means, that you start with arbitrarily many variables (in this case your stack variables from the stack machine) and find an allocation of assigning these variables to registers while at the same time trying to minimize the amount of register spills. Even a greedy algorithm should work sufficiently well in that case.
OTOT, for what reason do you actually want to dos this anyway? Re-assemble VM code?

[Conquest]

Originally Posted by mcp

OTOT, for what reason do you actually want to dos this anyway? Re-assemble VM code?

Yes . Also you got my question correctly. weird enough in themida cisc vm they preserve the register information while vmp completely wipes it (unless they are using some hidden tricks like water marking the register handlers or assign the vm pcode with certain algo which encrypts the register information) , i cant find the register information at all.
Thanks for your info anyway. I will look forward to have advice from more people involved in this area.