[tom_mellior]

> With a compiler (not jit), the whole bytecode would be further fully compiled to some C apis before being executed, making it effectively an "ahead of time" compilation.

This hinges at least on the question of what you mean by "the whole bytecode". If the source is made up of N functions, and you compile all N functions ("the whole bytecode" of the entire program) to machine code before you know if any of them will be executed: Yes, I'd agree that that's a form of ahead of time compilation. Is this what full-codegen used to do?

On the other hand, if the source is made up of N functions, and you only compile "the whole bytecode" of each of them to machine code one by one, only those that will actually be executed, and only when you are preparing to actually execute them: That's JIT compilation. Even if it is the very first execution (i.e., you have never even interpreted), even if the compilation doesn't use fancy profiling or sophisticated code generation or whatnot.

> since the code never was executed, there is very little static information to work with, so the compiled output is often just a giant unrolled interpret loop

I think you mean "dynamic" information. And "the compiled output is often just a giant unrolled interpret loop" is pretty much the definition of what a baseline JIT compiler produces.