diff --git a/Emscripten-build-instructions.md b/Emscripten-build-instructions.md new file mode 100644 index 00000000..5cb73db2 --- /dev/null +++ b/Emscripten-build-instructions.md @@ -0,0 +1,157 @@ +# Wasm Build Instructions + +It should be noted that the wasm build of CppInterOp is still experimental and subject to change to change. + +## CppInterOp Wasm Build Instructions + +This document first starts with the instructions on how to build a wasm build of CppInterOp. Before we start it should be noted that +unlike the non wasm version of CppInterOp we currently only support the Clang-REPL backend using llvm>19 for osx and Linux. +We will first make folder to build our wasm build of CppInterOp. This can be done by executing the following command + +```bash +mkdir CppInterOp-wasm +``` + +Now move into this directory using the following command + +```bash +cd ./CppInterOp-wasm +``` + +To create a wasm build of CppInterOp we make use of the emsdk toolchain. This can be installed by executing (we only currently +support version 3.1.45) +```bash +git clone https://github.com/emscripten-core/emsdk.git +cd emsdk +./emsdk install 3.1.45 +``` + +Go back upto the top level build directory using + +```bash +cd ../.. +``` + +and activate the emsdk environment + +```bash +./emsdk/emsdk activate 3.1.45 +source ./emsdk/emsdk_env.sh +``` + +Now clone the 19.x release of the LLVM project repository and CppInterOp (the building of the emscripten version of llvm can be +avoided by executing micromamba install llvm -c and setting the LLVM_BUILD_DIR appropriately) + + +```bash +git clone --depth=1 --branch release/19.x https://github.com/llvm/llvm-project.git +git clone --depth=1 https://github.com/compiler-research/CppInterOp.git +``` + +Now move into the cloned llvm-project folder and apply a required patch + +```bash +cd ./llvm-project/ +git apply -v ../CppInterOp/patches/llvm/emscripten-clang${{ matrix.clang-runtime }}-*.patch +``` + +We are now in a position to build an emscripten build of llvm by executing the following +```bash +mkdir build +cd build +emcmake cmake -DCMAKE_BUILD_TYPE=Release \ + -DLLVM_HOST_TRIPLE=wasm32-unknown-emscripten \ + -DLLVM_ENABLE_ASSERTIONS=ON \ + -DLLVM_TARGETS_TO_BUILD="WebAssembly" \ + -DLLVM_ENABLE_LIBEDIT=OFF \ + -DLLVM_ENABLE_PROJECTS="clang;lld" \ + -DLLVM_ENABLE_ZSTD=OFF \ + -DLLVM_ENABLE_LIBXML2=OFF \ + -DCLANG_ENABLE_STATIC_ANALYZER=OFF \ + -DCLANG_ENABLE_ARCMT=OFF \ + -DCLANG_ENABLE_BOOTSTRAP=OFF \ + -DCMAKE_CXX_FLAGS="-Dwait4=__syscall_wait4" \ + ../llvm +emmake make clang -j $(nproc --all) +emmake make lld -j $(nproc --all) +``` + +Once this finishes building we need to take note of where we built our llvm build. This can be done by executing the following + +```bash +export LLVM_BUILD_DIR=$PWD +``` + +We can move onto building the wasm version of CppInterOp. To do this execute the following + +```bash +cd ../../CppInterOp/ +mkdir build +cd ./build/ +emcmake cmake -DCMAKE_BUILD_TYPE=Release \ + -DUSE_CLING=OFF \ + -DUSE_REPL=ON \ + -DLLVM_DIR=$LLVM_BUILD_DIR/lib/cmake/llvm \ + -DLLD_DIR=$LLVM_BUILD_DIR/lib/cmake/lld \ + -DClang_DIR=$LLVM_BUILD_DIR/lib/cmake/clang \ + -DBUILD_SHARED_LIBS=ON \ + -DCMAKE_FIND_ROOT_PATH_MODE_PACKAGE=ON \ + -DCMAKE_INSTALL_PREFIX=$PREFIX \ + ../ +emmake make -j $(nproc --all) +``` + +Once this finishes building we need to take note of where we built CppInterOp. This can be done by executing the following + +```bash +export CPPINTEROP_BUILD_DIR=$PWD +``` + +## Xeus-cpp-lite Wasm Build Instructions + +A project which makes use of the wasm build of CppInterOp is xeus-cpp. xeus-cpp is a C++ Jupyter kernel. To build xeus-cpp we first need to +install several other dependencies. To create an Conda environment with this dependencies installed execute the following from the +CppInterOp build folder (these instructions will assume you have already installed micromamba) + +```bash +cd .. +micromamba create -f environment-wasm.yml --platform=emscripten-wasm32 +micromamba activate CppInterOp-wasm +export PREFIX=$MAMBA_ROOT_PREFIX/envs/CppInterOp-wasm +``` +Now we can build an wasm build of xeus-cpp by executing the following + +```bash +cd .. +git clone --depth=1 https://github.com/compiler-research/xeus-cpp.git +cd ./xeus-cpp +mkdir build +cd build +export CMAKE_PREFIX_PATH=$PREFIX +export CMAKE_SYSTEM_PREFIX_PATH=$PREFIX +emcmake cmake \ + -DCMAKE_BUILD_TYPE=Release \ + -DCMAKE_PREFIX_PATH=$PREFIX \ + -DCMAKE_INSTALL_PREFIX=$PREFIX \ + -DXEUS_CPP_EMSCRIPTEN_WASM_BUILD=ON \ + -DCMAKE_FIND_ROOT_PATH_MODE_PACKAGE=ON \ + -DCppInterOp_DIR="$CPPINTEROP_BUILD_DIR/lib/cmake/CppInterOp" \ + .. + emmake make -j $(nproc --all) install +``` + +To build Jupyter Lite with this kernel without creating a website you can execute the following + +```bash +cd ../.. +micromamba create -n xeus-lite-host jupyterlite-core +micromamba activate xeus-lite-host +python -m pip install jupyterlite-xeus +jupyter lite build --XeusAddon.prefix=$PREFIX +``` + +Once the Jupyter Lite site has built you can test the website locally by executing + +```bash +jupyter lite serve --XeusAddon.prefix=$PREFIX +```