Oh I was just using the simple test from that page nothing more.
I also tried the opencl examples linked in the wiki, and about 1/3 of them fail :/
How did you get them all to pass? Did you run them without X?
I ran everything from within X (i dont remember seeing anything about not using it with the simple tests) and i got gpu resets all over the place but most reported pass. Might be some failed, ill have to check again sometimes. First time i tried none worked and i recompiled everything - llvm+clang (aded the shared option that might have been the problem previously), mesa, drm, glamor, xf86-ati. Then they worked, but as i said i had gpu resets which might or might not be ok.
Also note that opencl/llvm git are quite unstable on mesa. I pulled the latest git (it said version 3.5svn) of llvm and clang, recompiled mesa and x restarted when i started libreoffice after a few seconds. After restart i observed that glamor wouldnt work anymore and x was started with exa rendering despite having explicitly set glamor in the xorg.conf. It seems that it started, crashed and started automatically again with auto settings which in my case its exa. Tried restarting the lightdm server a few times, but every time glamor crashed. I didnt have the time to mess around so i recompiled mesa without llvm which works with no issues.
So dont get your hopes up, opencl/llvm is very much a work in progress prone to breakage if you use the latest version with the latest features, dont try to use it for anything serious ATM.
When i first compiled (llvm without this option) it took a few hours to complete. I got a huge package after that and when i compiled the rest of the stuff i got crashes and errors in virtually all opengl apps. After compiling with this option, i had a reasonable 60 MB deb package and no issues until i recompiled with the 3.5 git llvm right after 3.4 was launched i think, where glamor crashed the x server.