presto-main/src/main/java/io/prestosql/spiller/AesSpillCipher.java/AesSpillCipher/decryptedMaxLength
class AesSpillCipher:    @Override
    public int decryptedMaxLength(int encryptedLength)
    {
        checkArgument(encryptedLength >= ivBytes, "encryptedLength must be >= %s", ivBytes);
        return encryptedLength - ivBytes;
    }