private long availableInSpace(Address startAddr) {
		return address.getAddressSpace().getMaxAddress().subtract(startAddr) + 1;
	}
<code>MemoryStateBuffer</code> provides a MemBuffer for instruction parsing use
which wraps an emulator MemoryState.  This implementation wraps all specified 
memory offsets within the associated address space.
Ghidra/Framework/Emulation/src/main/java/ghidra/pcode/emulate/EmulateMemoryStateBuffer.java