code: @Benchmark long setMaskX64(int reps) {
      long count = 64L * reps;
      long bitMask = 0L;
      for (int i = 0; i < count; i++) {
        bitMask |= 1 << (i & 0x3F);
      }
      return bitMask;
    }
docs: This benchmark attempts to measure performance of direct bit-manipulation.