DISCLAIMER: These notes are from the defunct k8 project which precedes SquirrelJME. The notes for SquirrelJME start on 2016/02/26! The k8 project was effectively a Java SE 8 operating system and as such all of the notes are in the context of that scope. That project is no longer my goal as SquirrelJME is the spiritual successor to it.
In allocation, figuring out the stack size to allocate is as simple as having a shared object in the allocation that indicates the total usage.
The allocation would be best if it were a map of Registers that are used by DecodedMethod instead as it can specify stack and local states as needed.