Customizing passes in llc while compiling .ll files

Hello, everyone!
I wanted to check work of my pass (which lives in a plugin) in a LLVM IR (.ll) files compiling pipeline.
I found the useful flag -run-pass=<passname>, but it says that the run-pass is for .mir file only.
How may I customize the optimization passes pipeline related to compiling the .ll file into the .s file?
And why -run-pass doesn’t accept the passes for customizing the optimization pipeline for .ll files?

Thanks in advance and sorry if asks something silly.

Kind regards,
Alex.