currently space is still acting as a sort of memory manager.
For proper linking, all objects must be reachable from space, hence the plural versions like messages and addresses (even they are instances, it is the list that is important)
To dish out instance to use, the head must be kept, ie next_XXX for intergers, return addresses and messages
rather use builder in two ways, than sometimes compiler and sometimes
builder
Also makes it possible to reuse builtin code in mom’s to_risc, as both
use builder. The builtin code by directly adding to compiler, the mom
code not.
