1 files changed, 134 insertions, 0 deletions
diff --git a/external/build-llvm.sh b/external/build-llvm.sh
new file mode 100755
index 000000000..a01158e78
--- /dev/null
+++ b/external/build-llvm.sh
@@ -0,0 +1,134 @@
+#!/usr/bin/env bash
+
+set -e
+
+help() {
+  me=$(basename "$0")
+  cat <<EOF
+$me: Fetch, build and install LLVM for Slang
+
+Options:
+  --repo: The source git repo, default: $repo
+  --branch: The branch (or tag) to fetch, default: $branch
+  --source-dir: Unpack and build in this directory: default $source_dir
+  --config: The configuration to build, default $config
+  --install-prefix: Install under this prefix
+  --: Any following arguments will be passed to the CMake configuration command
+EOF
+}
+
+#
+# Some helper functions
+#
+msg(){
+  printf "%s\n" "$1" >&2
+}
+
+fail() {
+  msg "$1"
+  exit 1
+}
+
+for prog in "cmake" "ninja" "git"; do
+  if ! command -v "$prog" &>/dev/null; then
+    msg "This script needs $prog, but it isn't in \$PATH"
+    missing_bin=1
+  fi
+done
+if [ "$missing_bin" ]; then
+  exit 1
+fi
+
+#
+# Temp dir with cleanup on exit
+#
+temp_dir=$(mktemp -d)
+cleanup() {
+  local exit_status=$?
+  rm -rf "$temp_dir"
+  exit $exit_status
+}
+trap cleanup EXIT SIGHUP SIGINT SIGTERM
+
+#
+# Options and parsing
+#
+repo=https://github.com/llvm/llvm-project
+branch=llvmorg-13.0.1
+source_dir=$temp_dir
+install_prefix=
+config=Release
+extra_arguments=()
+
+while [[ "$#" -gt 0 ]]; do
+  case $1 in
+  -h | --help) help; exit ;;
+  --repo) repo=$2; shift;;
+  --branch) branch=$2; shift;;
+  --source-dir) source_dir=$2; shift;;
+  --config) config=$2; shift;;
+  --install-prefix) install_prefix=$2; shift;;
+  --) shift; extra_arguments+=("$@"); break;;
+  *)
+    msg "Unknown parameter passed: $1"
+    help >&2
+    exit 1
+    ;;
+  esac
+  shift
+done
+
+[ -n "$repo" ] || fail "please set --repo"
+[ -n "$branch" ] || fail "please set --branch"
+[ -n "$source_dir" ] || fail "please set --source-dir"
+[ -n "$config" ] || fail "please set --config"
+[ -n "$install_prefix" ] || fail "please set --install-prefix"
+
+msg "##########################################################"
+msg "# Fetching LLVM from $repo at $branch"
+msg "##########################################################"
+git -c advice.detachedHead=false clone "$repo" --branch "$branch" "$source_dir" --depth 1
+
+msg "##########################################################"
+msg "# Configuring LLVM in $source_dir"
+msg "##########################################################"
+cmake_arguments_for_slang=(
+  # Don't build unnecessary things
+  -DLLVM_BUILD_LLVM_C_DYLIB=0
+  -DLLVM_INCLUDE_BENCHMARKS=0
+  -DLLVM_INCLUDE_DOCS=0
+  -DLLVM_INCLUDE_EXAMPLES=0
+  -DLLVM_INCLUDE_TESTS=0
+  -DLLVM_ENABLE_TERMINFO=0
+  -DCLANG_BUILD_TOOLS=0
+  -DCLANG_ENABLE_STATIC_ANALYZER=0
+  -DCLANG_ENABLE_ARCMT=0
+  -DCLANG_INCLUDE_DOCS=0
+  -DCLANG_INCLUDE_TESTS=0
+  # Requirements for Slang
+  -DLLVM_ENABLE_PROJECTS=clang
+  "-DLLVM_TARGETS_TO_BUILD=X86;ARM;AArch64"
+  -DLLVM_BUILD_TOOLS=1
+)
+build_dir=$source_dir/build
+mkdir -p "$build_dir"
+cmake \
+  -S "$source_dir/llvm" -B "$build_dir" \
+  -G "Ninja Multi-Config" \
+  "${cmake_arguments_for_slang[@]}" \
+  "${extra_arguments[@]}"
+
+msg "##########################################################"
+msg "# Building LLVM in $build_dir"
+msg "##########################################################"
+cmake --build "$build_dir" -j --config "$config"
+
+msg "##########################################################"
+msg "# Installing LLVM to $install_prefix"
+msg "##########################################################"
+cmake --install "$build_dir" --prefix "$install_prefix" --config "$config"
+
+msg "##########################################################"
+msg "LLVM installed in $install_prefix"
+msg "Please add $install_prefix to CMAKE_PREFIX_PATH"
+msg "##########################################################"