private int findLastNonZeroIndex() {
        for(int i=lastNonZeroIndex;i>=0;i--) {
            if (objs[i] != null) {
                return i;
            }
        }
        return -1;
    }
Finds the index of the last non-null value.
@return The index of the last non-null value. 0 will be returned
if the array is empty.
Ghidra/Framework/Generic/src/main/java/ghidra/util/datastruct/ObjectArray.java