Find code that my change has rendered unused

My case is a large project with a lots of code recognized as "unused" by IDE. However it's not: classes and methods get used by various form of reflection, and they are not marked by any annotation. So for me using the standard 'find unsued code' audit makes little sense.

What seems quite useful is comparing what was unused before my change and after it. Most of the items in this diff are likely the things I really can delete in the course of my change (though some of them may still be needed from reflections, e.g. from native code and cannot be deleted, so one has to be careful).

Does this count as a good feature idea? Or can I be slow and didn't notice IDEA already has one?