How is this PHP encoded?

Does anybody know how this PHP code is encoded? I don't know whether it's Zend, ionCube or something else.

<?php

if (!function_exists("T7FC56270E7A70FA81A5935B72EACBE29"))  {
    function T7FC56270E7A70FA81A5935B72EACBE29($TF186217753C37B9B9F958D906208506E)   { 
        $TF186217753C37B9B9F958D906208506E = base64_decode($TF186217753C37B9B9F958D906208506E);
        $T7FC56270E7A70FA81A5935B72EACBE29 = 0;
        $T9D5ED678FE57BCCA610140957AFAB571 = 0;
        $T0D61F8370CAD1D412F80B84D143E1257 = 0;
        $TF623E75AF30E62BBD73D6DF5B50BB7B5 = (ord($TF186217753C37B9B9F958D906208506E[1]) << 8) + ord($TF186217753C37B9B9F958D906208506E[2]);
        $T3A3EA00CFC35332CEDF6E5E9A32E94DA = 3;
        $T800618943025315F869E4E1F09471012 = 0; 
        $TDFCF28D0734569A6A693BC8194DE62BF = 16;
        $TC1D9F50F86825A1A2302EC2449C17196 = "";
        $TDD7536794B63BF90ECCFD开发者_如何学编程37F9B147D7F = strlen($TF186217753C37B9B9F958D906208506E);
?>

It's just obfuscated code. I'm guessing that it was generated by http://www.truebug.com/, judging by this cached Google page, but it could be from any similar product.

It's automatically generated code, and it's damn ugly. I don't think it's encoded - I just think the generator just threw a load of GUIDs into the code to use as function names.

My guess is that this code uses Obfuscation.
To obfuscate a code is to transform its source to a virtually unreadable analog. It's exactly the same functionality, but variable and function names are changed in a way which would make it very hard to read.

It's a usual practice used for code which can be disassembled (like .NET or any interpreted language like PHP, Ruby, Perl), to protect it as an intellectual property.

Check this question for details: Is there a code obfuscator for PHP?