OCCA Transpiler

Requirements

Minimum:

• CMake v3.26 or newer
• C++17 compiler(GCC 11 or newer)
• C11 compiler
• Clang 17(exactly)

Build

Setup clang 17

The current version of OCCA transpiler requires exactly clang 17. In future the transpiler will be updated to have compatibility layer to support newer versions of clang.

Install clang 17

wget https://raw.githubusercontent.com/opencollab/llvm-jenkins.debian.net/master/llvm.sh
sudo ./llvm.sh 17 all
rm llvm.sh

Build clang from source

git clone https://github.com/llvm/llvm-project.git
cd llvm-project
git checkout llvmorg-17.0.6
cmake -S llvm -B build -G Ninja -DCMAKE_INSTALL_PREFIX=<clang_install_prefix>  -DCMAKE_BUILD_TYPE=Release -DLLVM_PARALLEL_LINK_JOBS=1 -DLLVM_ENABLE_RTTI=ON -DCMAKE_BUILD_TYPE=Release -DCMAKE_POLICY_DEFAULT_CMP0094=NEW -DCMAKE_VERBOSE_MAKEFILE=ON -DCMAKE_FIND_USE_PACKAGE_REGISTRY=OFF  -DLLVM_ENABLE_PROJECTS="polly;lld;lldb;clang-tools-extra;llvm;clang"  -DLLVM_ENABLE_RUNTIMES="libunwind;libcxx;libcxxabi;compiler-rt"  -DLLVM_REQUIRES_RTTI=ON-DLLVM_ENABLE_RTTI=ON  -DLLVM_ENABLE_EH=ON  -DLLVM_POLLY_LINK_INTO_TOOLS=ON  -DLLVM_ENABLE_Z3_SOLVER=ON
ninja -C build install

Note: Replace <clang_install_prefix> with the desired installation path.
Note: Replace ninja with make if you are using make as the build system.
Note: In case of 'make' build system, add -j$(nproc) with -jN where N is the number of cores you want to use for the build
If your system has less than 32GB of RAM, it is recommended to use -j1 instead of -j$(nproc) to avoid running out of memory on linkage step.
Note: Use the same version of compiler to build clang and tanspiler itself.

Submodules

git submodule init
git submodule update

Compile

mkdir -p build && cd build
cmake .. && make -j$(($(nproc)-2))

If you use clang 17 built from source please specify path to it via option -DOCCA_LOCAL_CLANG_PATH=<clang_install_prefix>:

mkdir -p build && cd build
cmake -DOCCA_LOCAL_CLANG_PATH=<clang_install_prefix> .. && make -j$(($(nproc)-2))

OCCA-Tool

Normalize

Usage: normalize [--help] [--version] --input VAR [--output VAR]

convert OKL 1.0 to OKL 2.0 attributes C++ pure syntax

Optional arguments:
  -h, --help     shows help message and exits 
  -v, --version  prints version information and exits 
  -i, --input    input file OKL 1.0 [required]
  -o, --output   optional output file [nargs=0..1] [default: ""]

Transpile

Usage: transpile [--help] [--version] --backend VAR --input VAR [--normalize] [--output VAR]

transpile OKL to targeted backend

Optional arguments:
  -h, --help     shows help message and exits 
  -v, --version  prints version information and exits 
  -b, --backend  backends: {cuda, openmp} [required]
  -i, --input    input file [required]
  --normalize    should normalize before transpiling 
  -o, --output   optional output file [nargs=0..1] [default: ""]

Logging

Logging level can be set with OKLT_LOG_LEVEL enviroment variable.

Possible values:

• trace
• debug
• info
• warn
• err
• critical

Documentation