CUserTypeManager::getEntityList

function getEntityList()
{
	if($this->entityList === null)
	{
		$event = new BitrixMainEvent('main', 'onUserTypeEntityOrmMap');
		$event->send();

		foreach($event->getResults() as $eventResult)
		{
			if($eventResult->getType() == BitrixMainEventResult::SUCCESS)
			{
				$result = $eventResult->getParameters(); // [ENTITY_ID => 'SomeTable']
				foreach($result as $entityId => $entityClass)
				{
					if(mb_substr($entityClass, 0, 1) !== '\')
					{
						$entityClass = '\' . $entityClass;
					}

					$this->entityList[$entityId] = $entityClass;
				}
			}
		}
	}

	return $this->entityList;
}