protected TaintSet whenNull(long offset) {
		return TaintSet.EMPTY;
	}
Extension point: Behavior when there is no in-memory taint set at the given offset

<p>
This will be overridden by {@link TaintTraceSpace} to implement the lazy loading and
deserialization from a trace.

@param offset the offset
@return the taint set to use
Ghidra/Debug/TaintAnalysis/src/main/java/ghidra/pcode/emu/taint/plain/TaintSpace.java