DO NOT COMMIT: tweak premerge to use custom image

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Author: gburgessiv

.github/workflows/premerge.yaml

@@ -26,157 +26,23 @@ concurrency:
 jobs:
   premerge-checks-linux:
     name: Linux Premerge Checks (Test Only - Please Ignore Results)
-    defaults:
-      run:
-        # The premerge Linux docker instance keeps a pristine clone of LLVM in
-        # /home/gha/llvm-project; that should be used as our main workdir.
-        working-directory: /home/gha/llvm-project
     if: >-
         github.repository_owner == 'llvm' &&
         (github.event_name != 'pull_request' || github.event.action != 'closed')
-    runs-on: llvm-premerge-linux-runners
+    runs-on: ubuntu-latest
+    container:
+        image: ghcr.io/gburgessiv/llvm-ci-with-checkout:latest
     steps:
-      - name: Checkout LLVM
-        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
-        with:
-          path: /home/gha/llvm-project
-      - name: Setup ccache
-        uses: hendrikmuhs/ccache-action@a1209f81afb8c005c13b4296c32e363431bffea5 # v1.2.17
-        with:
-          max-size: "2000M"
-      - name: Build and Test
-        # Mark the job as a success even if the step fails so that people do
-        # not get notified while the new premerge pipeline is in an
-        # experimental state.
-        # TODO(boomanaiden154): Remove this once the pipeline is stable and we
-        # are ready for people to start recieving notifications.
-        continue-on-error: true
-        run: |
-          git config --global --add safe.directory '*'
-
-          source <(git diff --name-only HEAD~1...HEAD | python3 .ci/compute_projects.py)
-
-          if [[ "${projects_to_build}" == "" ]]; then
-            echo "No projects to build"
-            exit 0
-          fi
-
-          echo "Building projects: ${projects_to_build}"
-          echo "Running project checks targets: ${project_check_targets}"
-          echo "Building runtimes: ${runtimes_to_build}"
-          echo "Running runtimes checks targets: ${runtimes_check_targets}"
-
-          export CC=/opt/llvm/bin/clang
-          export CXX=/opt/llvm/bin/clang++
-
-          ./.ci/monolithic-linux.sh "${projects_to_build}" "${project_check_targets}" "${runtimes_to_build}" "${runtimes_check_targets}"
-      - name: Upload Artifacts
-        uses: actions/upload-artifact@65c4c4a1ddee5b72f698fdd19549f0f0fb45cf08 # v4.6.0
-        with:
-          name: Premerge Artifacts (Linux)
-          path: artifacts/
-          retention-days: 5
-          include-hidden-files: 'true'
-
-  premerge-checks-windows:
-    name: Windows Premerge Checks (Test Only - Please Ignore Results)
-    if: >-
-        github.repository_owner == 'llvm' &&
-        (github.event_name != 'pull_request' || github.event.action != 'closed')
-    runs-on: llvm-premerge-windows-runners
-    defaults:
-      run:
-        shell: bash
-    steps:
-      - name: Checkout LLVM
-        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
-        with:
-          fetch-depth: 2
-      - name: Setup ccache
-        uses: hendrikmuhs/ccache-action@a1209f81afb8c005c13b4296c32e363431bffea5 # v1.2.17
-        with:
-          variant: "sccache"
-          max-size: "2000M"
-      - name: Compute Projects
-        id: vars
-        run: |
-          source <(git diff --name-only HEAD~1...HEAD | python .ci/compute_projects.py)
-
-          if [[ "${projects_to_build}" == "" ]]; then
-            echo "No projects to build"
-          fi
-
-          echo "Building projects: ${projects_to_build}"
-          echo "Running project checks targets: ${project_check_targets}"
-
-          echo "windows-projects=${projects_to_build}" >> $GITHUB_OUTPUT
-          echo "windows-check-targets=${project_check_targets}" >> $GITHUB_OUTPUT
-      - name: Build and Test
-        # Mark the job as a success even if the step fails so that people do
-        # not get notified while the new premerge pipeline is in an
-        # experimental state.
-        # TODO(boomanaiden154): Remove this once the pipeline is stable and we
-        # are ready for people to start recieving notifications.
-        continue-on-error: true
-        if: ${{ steps.vars.outputs.windows-projects != '' }}
-        shell: cmd
+      - name: Seed LLVM repo
         run: |
-          set MAX_PARALLEL_COMPILE_JOBS=64
-          set MAX_PARALLEL_LINK_JOBS=64
-          call C:\\BuildTools\\Common7\\Tools\\VsDevCmd.bat -arch=amd64 -host_arch=amd64
-          bash .ci/monolithic-windows.sh "${{ steps.vars.outputs.windows-projects }}" "${{ steps.vars.outputs.windows-check-targets }}"
-      - name: Upload Artifacts
-        uses: actions/upload-artifact@65c4c4a1ddee5b72f698fdd19549f0f0fb45cf08 # v4.6.0
-        with:
-          name: Premerge Artifacts (Windows)
-          path: artifacts/
-          retention-days: 5
-          include-hidden-files: 'true'
-
-  premerge-check-macos:
-    name: MacOS Premerge Checks
-    runs-on: macos-14
-    if: >-
-      github.repository_owner == 'llvm' &&
-      (startswith(github.ref_name, 'release/') ||
-       startswith(github.base_ref, 'release/')) &&
-      (github.event_name != 'pull_request' || github.event.action != 'closed')
-    steps:
+          set -e
+          echo "Removing old workspace dir"
+          rmdir "${GITHUB_WORKSPACE}"
+          echo "Creating symlink"
+          ln -s /home/gha/llvm-project "${GITHUB_WORKSPACE}"
+          echo "Successfully linked"
       - name: Checkout LLVM
-        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        uses: gburgessiv/checkout@cd9bfd32b603629c83b862731b9177c640196083 # v4.2.2
         with:
-          fetch-depth: 2
-      - name: Setup ccache
-        uses: hendrikmuhs/ccache-action@a1209f81afb8c005c13b4296c32e363431bffea5 # v1.2.17
-        with:
-          max-size: "2000M"
-      - name: Install Ninja
-        uses: llvm/actions/install-ninja@main
-      - name: Build and Test
-        run: |
-          source <(git diff --name-only HEAD~2..HEAD | python3 .ci/compute_projects.py)
-
-          if [[ "${projects_to_build}" == "" ]]; then
-            echo "No projects to build"
-            exit 0
-          fi
-
-          echo "Building projects: ${projects_to_build}"
-          echo "Running project checks targets: ${project_check_targets}"
-
-          # -DLLVM_DISABLE_ASSEMBLY_FILES=ON is for
-          # https://github.com/llvm/llvm-project/issues/81967
-          # Disable sharding in lit so that the LIT_XFAIL environment var works.
-          cmake -G Ninja \
-                -B build \
-                -S llvm \
-                -DLLVM_ENABLE_PROJECTS="${projects_to_build}" \
-                -DLLVM_DISABLE_ASSEMBLY_FILES=ON \
-                -DCMAKE_BUILD_TYPE=Release \
-                -DLLDB_INCLUDE_TESTS=OFF \
-                -DLLVM_ENABLE_ASSERTIONS=ON \
-                -DCMAKE_C_COMPILER_LAUNCHER=ccache \
-                -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
-
-          # The libcxx tests fail, so we are skipping the runtime targets.
-          ninja -C build ${project_check_targets}
+          # This repo is frozen with the docker container; no need to clean.
+          clean: false