Re: How does LuaJIT's trace compiler work?

Created on 2020-08-20T05:23:18.198477

Loops are the preferred starting point for tracing.
The start of functions can sometimes start tracing.
"Small" inner loops may be unrolled and inlined.
Lots of heuristics are used to determine where to begin and end traces.
Story about how Cloudflare uses Luajit to power business logic; the tracing compiler takes apart the scripting and generates specialized traces for particular attacks so the system is continously optimized for what its doing *right now*.
Trace compiler generates less than per-method compiler; most of the process stays as bytecode and traces are not long.