presto-main/src/main/java/io/prestosql/type/DecimalOperators.java/DecimalOperators/multiplyLongLongLong
class DecimalOperators:    @UsedByGeneratedCode
    public static Slice multiplyLongLongLong(Slice a, Slice b)
    {
        try {
            Slice result = UnscaledDecimal128Arithmetic.multiply(a, b);
            throwIfOverflows(result);
            return result;
        }
        catch (ArithmeticException e) {
            throw new PrestoException(NUMERIC_VALUE_OUT_OF_RANGE, "Decimal overflow", e);
        }
    }