public Decimal128 fastUpdateFromInternalStorage(byte[] internalStorage, short scale) {
    this.scale = scale;
    this.signum = this.unscaledValue.fastUpdateFromInternalStorage(internalStorage);

    return this;
  }
Fats update from BigInteger two's complement representation
@param internalStorage BigInteger two's complement representation of the unscaled value
@param scale
common/src/java/org/apache/hadoop/hive/common/type/Decimal128.java