public HashMap<Long, Varnode> clearUniqueState() {
		HashMap<Long, Varnode> oldMap = uniqueMap;
		if (uniqueMap != null) {
			uniqueMap = new HashMap<Long, Varnode>();
		}
		return oldMap;
	}
When done processing a particular instruction, this method should be invoked to 
clear any unique Varnode state.
@return previous unique state
Ghidra/Features/Base/src/main/java/ghidra/util/state/ContextState.java