Filter by instruction pointer

[cgaebel]

Intel PT provides the ability to filter a trace by instruction pointer range. I can imagine using someone wanting to include only specific files, libraries, or functions in a trace. People could trace long time periods and collect data for only particularly problematic regions of code.

I'm not sure how flexible these filters are, whoever does this will need to play around with perf record --filter a bit to figure out what it can do.

[Xyene]

Ref -immediate-stop from #79, which used --filter internally.

[cgaebel]

That's distressing.