[LLVMdev] Slow jitter.

[Török Edwin]

On 2009-08-26 16:57, Óscar Fuentes wrote:
> llc needs 45 seconds. This is far worse than the 33 seconds used by the
> JIT. Maybe llc is using optimizations. My JIT have no optimizations
> enabled.
>
> Yup, llc -O0 takes 37.5 seconds.
>
> llc -pre-RA-sched=fast -regalloc=local takes 26 seconds. Much better but
> still slow IMO. The question is if this avoids the non-linear algorithms
> and if the generated code is faster enough to justify LLVM. I'll do some
> experimentation.
>
> The generated assembly file is 290K lines for unadorned llc and 616K
> lines for -pre-RA-sched=fast -regalloc=local. This does not inspire much
> hope :-)

Is this a Release or a Release-Asserts build?
You could try how much time it takes on a Release-Asserts build.

Also if you use -time-passes with llc it should show which pass in llc
takes so much time.

Best regards,
--Edwin