These are also people who don't understand you can JIT whatever language you like.
It's not common to JIT C or C++, but you could, and gain all of the profiling/whatever advantages. It's just not commonly done because the end result of a C/C++ compiler is "fast enough".
Plus, JIT's have a weird set of tradeoffs. You'd really need a hybrid model where you did expensive high level loop transformations statically, then left the IR alone and JIT'd it[1]. This whole set of ideas quickly gets into TeNDRA/ANDF territory, however.
[1] Of course, profiling at runtime through the JIT may discover some more places to loop transform.
It's not common to JIT C or C++, but you could, and gain all of the profiling/whatever advantages. It's just not commonly done because the end result of a C/C++ compiler is "fast enough". Plus, JIT's have a weird set of tradeoffs. You'd really need a hybrid model where you did expensive high level loop transformations statically, then left the IR alone and JIT'd it[1]. This whole set of ideas quickly gets into TeNDRA/ANDF territory, however.
[1] Of course, profiling at runtime through the JIT may discover some more places to loop transform.