Run JavaScriptCore's sampling profiler for a particular function
This is pretty low-level.
Things to know:
- LLint means "Low Level Interpreter", which is the interpreter that runs before any JIT compilation
- Baseline is the first JIT compilation tier. It's the least optimized, but the fastest to compile
- DFG means "Data Flow Graph", which is the second JIT compilation tier. It has some optimizations, but is slower to compile
- FTL means "Faster Than Light", which is the third JIT compilation tier. It has the most optimizations, but is the slowest to compile