What tools should be used to cut off excess unused code in a project?

Question

PHP

There is a project that contains a huge amount of old and unused code. There are many included but unused libraries. What are the best tools to find it all? It is clear that, ideally, it is necessary to review the entire code and cut off the excess, but perhaps the process is somehow automated or semi-automated. Share your experience plz.
PHP project using phpStorm. I can find usages in a storm.

Answer 1

As an option for ninja:
delete everything, leave the entry point, enable error output, include files on demand php errors

Answer 2

Take a look here: https://kcachegrind.github.io/html/Home.html
This is a list of downloadable modules and their links: It's great that this thing is free! PS Requires xdebug !