@Override
	public final int compareTo(Reference r) {
		int result = fromAddr.compareTo(r.getFromAddress());
		if (result == 0) {
			result = opIndex - r.getOperandIndex();
			if (result == 0) {
				return toAddr.compareTo(r.getToAddress());
			}
		}
		return result;
	}
@see java.lang.Comparable#compareTo(Object)
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/references/ReferenceDB.java