self_profile_counter
counter used by the self profiler (default: wall-time), one of:
wall-time (monotonic clock, i.e. std::time::Instant)
instructions:u (retired instructions, userspace-only)
instructions-minus-irqs:u (subtracting hardware interrupt counts for extra accuracy)
This feature has no tracking issue, and is therefore likely internal to the compiler, not being intended for general use.