I wrote a PHP source code encryption problem.

I wrote a PHP source code encryption problem. recently, the company gave me a question about PHP source code encryption, I still use 3DES to write an algorithm to encrypt the source code. when the program is running, the source code is decrypted, and the 3des key is stored in the encryption lock (IA300 of Longmai). now the problem is coming, the decrypted code writes a PHP source code encryption problem on its own.
Recently, the company gave me a question about PHP source code encryption. if you want to use 3DES to write an algorithm to encrypt the source code, when the program is running, the source code is decrypted, and the 3des key is stored in the encryption lock (IA300 of Longmai). The problem is that the decrypted code is only a value that does not run. what should I do? It is different from what I want to decrypt and continue running. how can this problem be solved? Don't use the Zend compiler and those open source compilers. the intensity is too low. thank you ....

------ Solution --------------------
Eval
------ Solution --------------------
Eval ('phpinfo ();');

Use eval