[llvm-dev] profiling JIT compiled code with perf

[Frank Tetzel via llvm-dev]

> Hello,
> 
> is there any support in LLVM for the jitdump format [1] of perf?
> 
> It enables perf report to also "zoom in" and annotate the JIT compiled
> code on assembly level with runtime percentage. It helps a lot to
> understand which parts of the generated code is the bottleneck.
> 
> I recently did a proof-of-concept for the JIT assembler asmjit [2]. It
> just dumps the generated code in the right format and mmaps the file
> to let perf record know about it. perf report picks it up
> automatically.
> 
> So, is there any profiling support for JIT compiled code?


I guess that's a no.

Is there a simple way to get a pointer to the assemble code and the
exact size in bytes? Or should I just use the function pointer? Where
do I get the size?

Then I could at least dump the native code. Profiling on assembly level
would already help a lot.

Regards,
Frank