code: private static void maskOutWord(int[] array, int index, int from, int to) {
      if (from == to) {
        return;
      }
  
      int word = wordAt(array, index);
      if (word == 0) {
        return;
      }
  
      int mask;
      if (from != 0) {
        mask = 0xffffffff >>> (32 - from);
      } else {
        mask = 0;
      }
      // Shifting by 32 is the same as shifting by 0.
      if (to != 32) {
        mask |= 0xffffffff << to;
      }
  
      word &= mask;
      array[index] = word & WORD_MASK;
    }
docs: Sets all bits to false in a word within the given bit range.
  
  @param array The array.
  @param index The word index.
  @param from The lower bit index.
  @param to The upper bit index.