public static long pop_andnot(Object base1, long arr1Addr, Object base2, long arr2Addr, int wordOffset, int numWords) {
        long popCount = 0;
        for (int i = wordOffset, end = wordOffset + numWords; i < end; ++i) {
            popCount += Long.bitCount(Platform.getLong(base1, arr1Addr + (i << 3)) & ~Platform.getLong(base2, arr2Addr + (i << 3)));
        }
        return popCount;
    }
Returns the popcount or cardinality of A & ~B.
Neither array is modified.
indexr-common/src/main/java/io/indexr/util/BitUtil.java