// Código do loadLibrary
public function loadLibrary($lib){
            if(file_exists('libs/' . $lib . '.php')){
                include 'libs/' . $lib . '.php';
            }
        }

//Código do Autoload

<?php

    session_start();

    require 'config.php';

    spl_autoload_register(function ($class){
        if(strpos($class, 'Controller') > -1){
            if(file_exists('controllers/' . $class . '.php')){
                require_once 'controllers/' . $class . '.php';
            }
        }else if(file_exists('models/' . $class . '.php')){
            require_once 'models/' . $class . '.php';
        }else{
            require_once 'core/' . $class . '.php';
        }
    });

    $core = new Core();
    $core->run();

?>