public static void fillZero(Object base, long arrAddr, int fromWord, int toWord) {
        MemoryUtil.setMemory(base, arrAddr + (fromWord << 3), (toWord - fromWord) << 3, (byte) 0);
    }
A variety of high efficiency bit twiddling routines.
indexr-common/src/main/java/io/indexr/util/BitUtil.java