[workflows] Setup Windows x64/arm64 GitHub action for Classic Flang LLVM

* Extend pre-compile_llvm workflow with a Windows job which
defines build strategy for X64 and ARM64 architectures
to produce prebuilt LLVM binaries for both platform.
Currently Windows on ARM job is disabled, until
an official will be available.

* Also enable Classic Flang LLVM testing on Windows x64 only.
Some tests are failing on Windows on ARM, so we don't run
tests on WoA until they are fixed.

Author: kaadam

.github/workflows/llvm-project-tests.yml

@@ -74,17 +74,29 @@ jobs:
           # We're using a specific version of macOS due to:
           # https://github.com/actions/virtual-environments/issues/5900
           - macOS-11
+          - windows-latest
+        include:
+          # Enable Windows on ARM build, when an official
+          # self-hosted machine is available.
+          # - os: self-hosted
+          #   target: AArch64
+          #   arch: arm64
+          - os: windows-latest
+            arch: amd64
+
     steps:
       - name: Setup Windows
-        if: startsWith(matrix.os, 'windows')
+        if: startsWith(matrix.os, 'windows') || startsWith(matrix.os, 'self')
         uses: llvm/actions/setup-windows@main
         with:
-          arch: amd64
-      # On Windows, starting with win19/20220814.1, cmake choose the 32-bit
-      # python3.10.6 libraries instead of the 64-bit libraries when building
-      # lldb.  Using this setup-python action to make 3.10 the default
-      # python fixes this.
+          arch: ${{ matrix.arch }}
+      # By default CMake chooses the most recent 32-bit libraries instead of
+      # the 64-bit libraries when building and testing LLVM or Clang.
+      # 32 bit version causes a memory error during the testing.
+      # On 'windows-latest' GitHub image (VS2022) 3.11 (32bit) version is installed.
+      # Using this setup-python action to make 3.11 (64bit) the default
       - name: Setup Python
+        if: ${{ matrix.os != 'self-hosted' }}
         uses: actions/setup-python@v5
         with:
           python-version: ${{ inputs.python_version }}
@@ -94,10 +106,18 @@ jobs:
       # actions/checkout deletes any existing files in the new git directory,
       # so this needs to either run before ccache-action or it has to use
       # clean: false.
+      - name: Setup psutil
+        # psutil is not available on Windows on ARM.
+        if: startsWith(matrix.os, 'windows')
+        run: pip install psutil
+      - name: Check tools
+        run: python --version
       - uses: actions/checkout@v4
         with:
           fetch-depth: 250
       - name: Setup ccache
+        # ccache is not available for Windows on ARM.
+        if: ${{ matrix.os != 'self-hosted' }}
         uses: hendrikmuhs/ccache-action@v1
         with:
           # A full build of llvm, clang, lld, and lldb takes about 250MB
@@ -111,6 +131,16 @@ jobs:
           max-size: 2G
           key: ${{ matrix.os }}
           variant: sccache
+      - name: Test clang Windows
+        # Some LLVM tests are failing on Windows On ARM,
+        # so this step is skipped on WoA until they are fixed.
+        if: ${{ matrix.os == 'windows-latest' }}
+        run: |
+          $pcount = $($(Get-WmiObject -class Win32_ComputerSystem).numberoflogicalprocessors)
+          python .\scripts\build_llvm_project.py -d build -t ${{ matrix.target }} --cmake-param=-DLLVM_ENABLE_ASSERTIONS=ON -j $pcount
+          cd build
+          ninja check-all
+        shell: powershell
       - name: Test clang macOS
         if: ${{ matrix.os == 'macOS-11'}}
         env:

.github/workflows/pre-compile_llvm.yml

@@ -8,6 +8,7 @@ on:
 
 jobs:
   build:
+    name: Ubuntu Linux
     runs-on: ubuntu-20.04
     strategy:
       matrix:
@@ -80,3 +81,56 @@ jobs:
         with:
           name: llvm_build_${{ matrix.target }}_${{ matrix.cc }}_${{ matrix.version }}_${{ steps.extract_branch.outputs.branch }}
           path: llvm_build.tar.gz
+
+  build-win:
+    name: Windows build
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        include:
+          - os: windows-latest
+            arch: amd64
+            target: X86
+          # Enable Windows on ARM build, when an official
+          # self-hosted machine is available.
+          # - os: self-hosted
+          #   arch: arm64
+          #   target: AArch64
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Setup Windows
+        uses: llvm/actions/setup-windows@main
+        with:
+          arch: ${{ matrix.arch }}
+
+      - name: Setup Ninja
+        uses: llvm/actions/install-ninja@main
+
+      - name: Check tools
+        run: |
+          git --version
+          cmake --version
+          clang --version
+          ninja --version
+          python --version
+
+      - name: Extract branch name
+        id: extract_branch
+        run: echo "branch=$(("${{ github.ref }}" -split "/")[-1])" >> $env:GITHUB_OUTPUT
+
+      - name: Build llvm
+        shell: powershell
+        run: |
+          $pcount = $($(Get-WmiObject -class Win32_ComputerSystem).numberoflogicalprocessors)
+          python .\scripts\build_llvm_project.py -d build -t ${{ matrix.target }} --cmake-param=-DLLVM_ENABLE_ASSERTIONS=ON -j $pcount -v
+          cd ..
+          7z a llvm_build.7z $pwd/classic-flang-llvm-project/
+          Copy-Item llvm_build.7z -Destination $pwd/classic-flang-llvm-project/
+
+      - name: Upload llvm
+        uses: actions/upload-artifact@v3
+        with:
+          name: llvm_build_win_${{ matrix.arch }}_clangcl_${{ steps.extract_branch.outputs.branch }}
+          path: ${{ github.workspace }}\llvm_build.7z