Function UpperBoundNonsortingDecimalSize

postgres/parser/encoding/decimal.go:724–730

UpperBoundNonsortingDecimalSize returns the upper bound number of bytes that the decimal will need for the non-sorting encoding.

(d *apd.Decimal)

// UpperBoundNonsortingDecimalSize returns the upper bound number of bytes
// that the decimal will need for the non-sorting encoding.
func UpperBoundNonsortingDecimalSize(d *apd.Decimal) int {
	// Makeup of upper bound size:
	// - 1 byte for the prefix
	// - MaxVarintLen for the exponent
	// - WordLen for the big.Int bytes
	return 1 + MaxVarintLen + WordLen(d.Coeff.Bits())
}

// Taken from math/big/arith.go.
const bigWordSize = int(unsafe.Sizeof(big.Word(0)))