Header files that come with CUDA are assuming split host/device
compilation and are not usable by clang out of the box.
With a bit of preprocessor magic it's possible to twist them
into something clang can use.
This wrapper always includes CUDA headers exactly the same way during
host and device compilation passes and produces identical preprocessed
content during host and device side compilation for sm_35 GPUs. Device
compilation passes for older GPUs will see a smaller subset of device
functions supported by particular GPU.
The wrapper assumes specific contents of CUDA header files and works
only with CUDA 7.0 and 7.5.
Differential Revision: http://reviews.llvm.org/D13171
llvm-svn: 253388
c29db84419