[PATCH] OpenCL half support

Several companies have expressed interest in adding support for the half
data type. Some code from our previous patch
(http://lists.cs.uiuc.edu/pipermail/llvmdev/2011-July/042043.html) made it
into ToT (at http://llvm.org/viewvc/llvm-project?view=rev&revision=146786).

Please review further changes required.

Many thanks,
Anton.

half-llvm.patch (5.06 KB)