Add CMake HIP language support

[cgmb]

Build Instructions

1. Install ROCm 4.5.2
2. Install CMake 3.21.3 or later
3. Install libnuma and kmod (so that rocm_agent_enumerator works)
4. Build rocRAND:

HIPCXX=/opt/rocm/llvm/bin/clang++ \
CXX=/opt/rocm/llvm/bin/clang++ \
CC=/opt/rocm/llvm/bin/clang \
cmake -S. -Bbuild -GNinja \
  -DBUILD_HIPRAND=OFF \
  -DBUILD_FILE_REORG_BACKWARD_COMPATIBILITY=OFF \
  -DROCRAND_CMAKE_HIP_LANGUAGE=ON

With these changes, the above command will build a version of the library compatible with the system it's running on. If you want specific GPU architectures, append -DCMAKE_HIP_ARCHITECTURES='gfx906:xnack-;gfx1030' (replacing the example gfx906:xnack-;gfx1030 values with your chosen semi-colon delimited list of AMDGPU target ids).

Related CMake Documentation

• CMAKE_HIP_ARCHITECTURES
• CMAKE_HIP_STANDARD
• HIPCXX

[pfultz2]

You still need to call find_package(hip) when using hip language. Libraries like rocRAND need to provide hip::host in the targets interface because it includes hip's runtime API headers.

[cgmb]

Thanks. I was just about to request your review. I haven't yet tested this with downstream libraries.

[pfultz2]

Ah wait it looks like rocRAND actually needs hip::device as it includes hip's device headers:

https://github.com/ROCmSoftwarePlatform/rocRAND/blob/develop/library/include/rocrand/rocrand.h#L29

We would need two different targets to support using rocRAND with HIP language and with CXX language.

[cgmb]

It's not actually clear to me why it includes <hip/hip_runtime.h>. rocRAND appears to provide a C99 API. Sadly, the documentation is... lacking.

EDIT: Oh, I see. rocrand.h is a C API but rocrand.hpp clearly does need <hip/hip_runtime.h>.

[cgmb]

We would need two different targets to support using rocRAND with HIP language and with CXX language.

Maybe we could detect the language with a generator expression? I'm not entirely sure it's possible, but I was thinking something like:

set_property(TARGET roc::rocrand APPEND PROPERTY
  INTERFACE_LINK_LIBRARIES "$<$<NOT:$<COMPILE_LANGUAGE:HIP>>:hip::device>"
)

[Maetveis]

HI! rocRAND developer here, thank you for getting this off the ground. I believe cmake HIP support for rocRAND would simplify many projects that depend on rocRAND. I added a few comments, and will try this out soon.

I think I can help answer some questions regarding the project if you need anything.

[Maetveis]

IMO CUDA and HIP language support should be uniformly handled in rocRAND, so similar to other projects I would rather have an option like ROCRAND_LANGUAGE (the name is not important) which could be set to either HIP or CUDA.
If this variable is not set then the old behaviour applies based on the C++ compiler set (hipcc or clang -> HIP without cmake language support, gcc or nvcc -> CUDA), if set it overwrites this detection and forces either HIP or CUDA cmake language.

[cgmb]

That's an interesting thought. I'll change this behaviour from ROCRAND_CMAKE_HIP_LANGUAGE=ON to ROCRAND_CMAKE_LANG=HIP. The default would be ROCRAND_CMAKE_LANG=CXX, and if somebody wants to implement CMake CUDA language support, it would be ROCRAND_CMAKE_LANG=CUDA.

[Maetveis]

It would be better to have these lines together with the lines for CUDA a few lines below.

[Maetveis]

Nit: for benchmarks an if statement is used, but here its a generator expression. I would stick to the if in both places for consistency, and because this setting is known at configure time, a generator expression is not required.

[saadrahim]

This has been sitting around for a while. Should it be resurrected?

[cgmb]

This has been sitting around for a while. Should it be resurrected?

Maybe, but I don't have the bandwidth to do that quite yet.

The official Linux and Windows builds now both use CMake 3.22, so if this PR were finished, we could begin to use the CMake HIP language support in our official builds.