@SuppressWarnings("fallthrough")
  public static long divide(long p, long q, RoundingMode mode) {
    checkNotNull(mode);
    long div = p / q; // throws if q == 0
    long rem = p - q * div; // equals p % q

    if (rem == 0) {
      return div;
    }

    /*
     * Normal Java division rounds towards 0, consistently with RoundingMode.DOWN. We just have to

	MULHU	X5, X6, X7				// b3335302
	MULHSU	X5, X6, X7				// b3235302
	MULW	X5, X6, X7				// bb035302

	// 13.2: Division Operations
	DIV	X5, X6, X7				// b3435302
	DIVU	X5, X6, X7				// b3535302
	REM	X5, X6, X7				// b3635302
	REMU	X5, X6, X7				// b3735302
	DIVW	X5, X6, X7				// bb435302
	DIVUW	X5, X6, X7				// bb535302
	REMW	X5, X6, X7				// bb635302
	REMUW	X5, X6, X7				// bb735302