@Mark-Simulacrum: I admit I don't quite understand how the existing -Zself-profile support works for the benchmark commands. Anyway, this adds support for the profile command.

How would you feel about not running the tools within perf, and instead expecting that folks will cd Zsp && crox or so?

I'm not opposed, just not sure if they're slow or not and if there's reasons why people wouldn't want to run all of them...

Other than that, I think it's likely fine to merge this. I don't think we need to match the pre-existing support for self-profile summaries coupled to perf stat; and the new code modulo my comment seems fine as well.

(Feel free to merge with my comment resolved).

For the other profilers I've taken the approach of doing as much work for the user as possible, so they don't have to run any additional tools. (And "they" is usually "me"! :)

I haven't used the measureme tools much but they seem pretty speedy -- much faster than all the Valgrind tools, which easily incur slowdowns of 5-10x.