Limited amount of runtime information associated with compiled frames

[ezyang]

tlparse currently is a compile time only metrics collector. However, there is a small amount of runtime information that I think would be really useful:

1. How many times a particular compiled frame was hit. In particular, if we recompile multiple times, we might be interested to know how hot each of the particular recompiles are, which tells you if there is some warmup / unspec thing going on, or if there is legitimate multiple dispatch going on
2. How quickly the compiled frames run, a sort of poor man's profiling, but mostly I just want to see the timings from a compiled products perspective, as opposed to the usual performance trace perspective