Phoronix: Benchmarking LLVM & Clang Against GCC 4.5

FYI

http://www.phoronix.com/scan.php?page=article&item=gcc_llvm_clang&num=1

For Apache and Dhrystone, the performance boost is good (but only the
former is really important), but for the rest, especially those with
image/sound processing, and HMMR, it's still far behind. Is this only
because there is no auto vectorization in LLVM?

Would be good to know why some programs were not compiled with Clang.

yup.
it's a bit strange, that they couldn't compile php.

I compile php with clang for several months (at least) and it just works

Could be a temporary broken svn version. They could've waited until
2.7 was officially out, couldn't they? :wink:

cheers,
--renato

http://systemcall.org/

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> FYI
> http://www.phoronix.com/scan.php?page=article&item=gcc_llvm_clang&num=1

For Apache and Dhrystone, the performance boost is good (but only the
former is really important), but for the rest, especially those with
image/sound processing, and HMMR, it's still far behind. Is this only
because there is no auto vectorization in LLVM?

Doesn't llvm-gcc still lack autovectorization support as well? It's
numbers are closer to the stock gcc releases suggesting the problem
isn't from the absence of vectorization, no?
           Jack

We haven't spent much time on Clang code quality. The results are
"interesting", but hardly surprising.

This is something I hope to spend some time on in the upcoming months, FWIW.

- Daniel