In CogVMSimulator>>interpret method:
atEachStepBlock value. "N.B. may be nil"
self dispatchOn: currentBytecode in: BytecodeTable.
localIP := localIP - 1. "undo the pre-increment of IP before returning"
Under what conditions will the loop terminate?
If it terminates, the following statement assumes that the last
instruction was a single-byte bytecode and no extended multi-byte
instructions were involved. Is this fortuitous or by design?