ROTRV	$63, R22	// 0036b7fe


//	LAND/LXOR/LNOR/LOR rreg ',' rreg
//	{
//		outcode(int($1), &$2, 0, &$4);
//	}
	AND	R14, R8		// 010e4024
	XOR	R15, R9		// 012f4826
	NOR	R16, R10	// 01505027
	OR	R17, R11	// 01715825

//	LAND/LXOR/LOR imm ',' rreg
//	{
//		outcode(int($1), &$2, 0, &$4);
//	}
	AND	$11, R17, R7	// 3227000b
	XOR	$341, R1, R23	// 38370155
	OR	$254, R25, R13	// 372d00fe
//

	ORW	$65536, R1            // a51a0001
	ORW	$-2, R1               // c01dfffffffe
	XOR	R1, R2                // b9820021
	XOR	R1, R2, R3            // b9e72031
	XOR	$1, R1                // c01700000001
	XOR	$131071, R1           // c0170001ffff
	XOR	$65536, R1            // c01700010000
	XOR	$-2, R1               // c0a1fffffffeb982001a
	XORW	R1, R2                // 1721
	XORW	R1, R2, R3            // b9f72031

	AND	$1, X5					// 93f21200
	OR	X6, X5, X7				// b3e36200
	OR	X5, X6					// 33635300
	OR	$1, X5, X6				// 13e31200
	OR	$1, X5					// 93e21200
	XOR	X6, X5, X7				// b3c36200
	XOR	X5, X6					// 33435300
	XOR	$1, X5, X6				// 13c31200
	XOR	$1, X5					// 93c21200

	AUIPC	$0, X10					// 17050000
	AUIPC	$0, X11					// 97050000
	AUIPC	$1, X10					// 17150000
	AUIPC	$-524288, X15				// 97070080

     * with each letter representing a 4-byte word: ABCDABCDABCDABCD... and to calculate
     * CRC(A000A000A000...), CRC(0B000B000B...), CRC(00C000C000C...), CRC(000D000D000D...)
     * and then to XOR them together.  The STRIDE_TABLE enables us to hash an int followed by 12
     * zero bytes (3 ints), while the BYTE_TABLE is for advancing one byte at a time.

	}
	return v.toPromName(mg.CollectorPath.metricPrefix())
}

func (mg *MetricsGroup) validate() {
	if len(mg.Descriptors) == 0 {
		panic("Descriptors must be set")
	}

	// For bools A and B, A XOR B <=> A != B.
	isExactlyOneSet := (mg.loader == nil) != (mg.bucketLoader == nil)
	if !isExactlyOneSet {
		panic("Exactly one Loader function must be set")
	}

  /** Returns a byte string that differs from this one by one bit. */
  private fun ByteString.offByOneBit(): ByteString {
    return Buffer()
      .write(this, 0, size - 1)
      .writeByte(this[size - 1].toInt() xor 1)
      .readByteString()
  }

  private fun date(s: String): Date {
    return SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZ").run {
      timeZone = TimeZone.getTimeZone("GMT")
      parse(s)
    }