Can I detect pragma in ASTConsumer?

Hi, I'm new to Clang, and got stuck for days. I am not sure if this is a right place for newbie questions, so please let me know if it isn't.

I'm trying to make new pragma for my program. I figured by looking at the tutorial that PragmaHandler with PragmaHandlerRegistry can do the trick.

However, I am already using FrontendAction and ASTConsumer for other purposes.

I wonder if I can use PragmaHandler inside FrontendAction (I am not getting how to invoke it), without it having to be a seperate plugin.

Or are the pragmas already gone when ASTConsumer kicks in (is plugin the only way)? How these work together as a pipeline is very vague to me.

Any guidance will be very helpful.

Thank you.