[LLVMdev] slow on raspberry pi

Torsten RĂ¼ger torsten at villataika.fi
Fri Jan 18 03:03:08 PST 2013


I have been reading about llvm and clang and vmkit, and must say: great work guys.

So when i got my raspberry pi, and having read that llvm is better at arm than gcc, i compiled llvm on the pi. The pi has a soc with armv6 (i don't know what that means exactly though).
The pi is not fast and llvm with clang compilation took 22 h, but worked. hurrah.
Then i compiled llvm/clang with itself and was pleased it took "only" 12 hours. even better.

But then I compiled linpack and clang numbers were less than 1/4 off gcc compiled  :-(    (9000kFlops about)

Now according to this http://elinux.org/RPi_Performance  there is something with compiler settings, hard/soft floats and possibly the exact target (armv6XXX) of the pi to make it better.

My question is: has anybody else tried this, or could tell me what i could try to remedy this.


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20130118/09d43f3e/attachment.html>

More information about the llvm-dev mailing list