}

// Checksum returns the CRC-64 checksum of data
// using the polynomial represented by the [Table].
func Checksum(data []byte, tab *Table) uint64 { return update(0, tab, data) }

// tableSum returns the ISO checksum of table t.
func tableSum(t *Table) uint64 {
	var a [2048]byte
	b := a[:0]
	if t != nil {
		for _, x := range t {
			b = byteorder.BeAppendUint64(b, x)
		}
	}
	return Checksum(b, MakeTable(ISO))

// ChecksumIEEE returns the CRC-32 checksum of data
// using the [IEEE] polynomial.
func ChecksumIEEE(data []byte) uint32 {
	ieeeOnce.Do(ieeeInit)
	return updateIEEE(0, data)
}

// tableSum returns the IEEE checksum of table t.
func tableSum(t *Table) uint32 {
	var a [1024]byte
	b := a[:0]
	if t != nil {
		for _, x := range t {
			b = byteorder.BeAppendUint32(b, x)
		}
	}
	return ChecksumIEEE(b)