public void xor(DirectBitMap other) {
        assert wlen == other.wlen;

        int pos = wlen;
        while (--pos >= 0) {
            setWord(pos, word(pos) ^ other.word(pos));
        }
    }
this = this XOR other

@param other The other bitset.
indexr-common/src/main/java/io/indexr/util/DirectBitMap.java