presto-spi/src/main/java/io/prestosql/spi/type/UnscaledDecimal128Arithmetic.java/UnscaledDecimal128Arithmetic/rescale
class UnscaledDecimal128Arithmetic:    public static Slice rescale(Slice decimal, int rescaleFactor)
    {
        if (rescaleFactor == 0) {
            return decimal;
        }
        else {
            Slice result = unscaledDecimal();
            rescale(decimal, rescaleFactor, result);
            return result;
        }
    }