CHIP-SPV

CHIP-SPV that aims to make HIP and CUDA portable to platforms which support SPIR-V as the device intermediate representation. Currently CHIP-SPV supports OpenCL and Level Zero as the low-level runtime alternatives.

This project is an integration of HIPCL and HIPLZ projects.

For CHIP-SPV User documentation, read this. For CHIP-SPV Developer documentation, read this. For a list of (un)supported features in CHIP-SPV, read this.

Prerequisites

• Cmake >= 3.18.0
• Clang 14 or 15
  • Can be installed, for example, by adding the LLVM's Debian/Ubuntu repository and installing packages 'clang-15 llvm-15 clang-tools-15'. NOTE: The Ubuntu clang package does not provide a symlink for clang++, only clang++-14 is availble. If you plan on using hipcc you will need to make this symlink manually to ensure that clang++ is available in HIP_CLANG_PATH.
• SPIRV-LLVM-Translator from a branch matching to the clang version: (e.g. llvm_release_150 for Clang 15.0) llvm-spirv
• For Level Zero Backend
  • Intel Compute Runtime and
  • oneAPI Level Zero Loader
• For OpenCL Backend
  • OpenCL 2.0 or 3.0 implementation with coarse grained Shared Virtual Memory and SPIR-V input supported.

Downloading Sources

git clone https://github.com/CHIP-SPV/chip-spv.git -b Release-0.9
cd chip-spv
git submodule update --init --recursive

Building

mkdir build
cd build

cmake .. \
 -DCMAKE_CXX_COMPILER=clang++ \
 -DCMAKE_C_COMPILER=clang \
 -DCMAKE_INSTALL_PREFIX=<install location>

make
make install

Note: At the moment the build assumes it finds the following LLVM project binaries with the given names 'clang++', 'clang' and 'llvm-link'. Thus, make sure you have symlinks setup to the correct versions before building chip-spv. See Issue 133).

Useful options:

• -DCMAKE_BUILD_TYPE=<Debug(default), Release, RelWithDebInfo>
• to provide a path to separately built SPIRV-LLVM translator, use -DLLVM_SPIRV_BINARY=/path

The documentation will be placed in doxygen/html.

Building & Running Unit Tests

make build_tests
make check # runs only tests that are expected to work

Building documentation

Make sure you have doxygen installed. Then:

....
cd build
cmake .....
make gendocs

The documentation will be placed in doxygen/html.

Troubleshooting

Missing Double Precision Support

When running the tests on OpenCL devices which do not support double precision floats, there will be multiple tests that will error out.

It might be possible to enable software emulation of double precision floats for Intel iGPUs by setting two environment variables to make kernels using doubles work but with the major overhead of software emulation:

export IGC_EnableDPEmulation=1
export OverrideDefaultFP64Settings=1