Hello, On 14.11.2010 0:08, Xinliang David Li wrote:
I re-measured the performance difference using trunk gcc and trunk clang/llvm on a core-2 box. -fno-strict-aliasing is added to gcc because clang/llvm's type based aliasing is not incomplete and not enabled by default. I also added -fomit-frame-pointer to clang/llvm as this is gcc's default. The base option is -O2.
It would be very interesting to compare also peak numbers, i.e. with LTO and strict aliasing enabled, as well as -O3 and -ffast-math/-funroll-loops, similar to Vlad's or OpenSUSE's options. Can you try to measure these? Maybe you can also run SPEC2k6, if there is enough machine resources, but that's probably asking too much...
Andrey
