Does RJIT get JIT compiled... by itself? That would be lovely in the sense that as RJIT finds more optimizations to speed up code, it would become itself faster.
I mean, that's what happens with JITs like Graal. It can present a warmup issue which is part of the reason Graal did so much work to enable AOT compilation.
How many levels of JIT would be too many I wonder
AOT + JIT + PGO (profile guided optimization) is where things are at.