Use shared volume to cache packages (#217)

GitHub has a limit of 10GB of cache per repository. Plus caches are
scoped to a key and a branch, so a cache created on branch-A won’t be
accessible by branch-B unless branch-A is the default branch. Since
llvm-target is not the default branch, we cannot use GitHub cache
directly.

.github/workflows/build_and_test_2.yaml

@@ -23,13 +23,27 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
 
+      - name: Check if pip cache exists
+        env:
+          # Increase this value to reset cache
+          CACHE_NUMBER: 1
+        run: |
+          PIP_CACHE_KEY="pip-3.9-${{ hashFiles('.pre-commit-config.yaml') }}-${{ env.CACHE_NUMBER }}"
+          PIP_CACHE="/cache/$PIP_CACHE_KEY"
+          echo "PIP_CACHE=$PIP_CACHE" >> "${GITHUB_ENV}"
+          if [[ -d $PIP_CACHE ]]; then
+            echo "Python cache found for key $PIP_CACHE_KEY"
+            echo $PIP_CACHE > .pip-cache
+            mkdir -p $HOME/.cache
+            ln -s $PIP_CACHE $HOME/.cache/pip
+          else
+            echo "Python cache not found for key $PIP_CACHE_KEY"
+          fi
+
       - name: Install Python 3.9
         uses: actions/setup-python@v4
         with:
           python-version: '3.9'
-          cache: 'pip'
-          cache-dependency-path: |
-            .pre-commit-config.yaml
 
       - name: Run pre-commit checks
         run: |
@@ -38,6 +52,14 @@ jobs:
           python3 -m pre_commit run --all-files --verbose yapf &> /dev/null || true
           python3 -m pre_commit run --all-files --verbose
 
+      - name: Save pip cache
+        if: ${{ hashFiles('.pip-cache') == '' }}
+        run: |
+          TMPDIR=/cache/${{ github.run_id }}-$RANDOM
+          mkdir $TMPDIR
+          cp -r $HOME/.cache/pip/* $TMPDIR/
+          mv $TMPDIR $PIP_CACHE
+
   integration-tests:
     name: Integration tests
     runs-on:
@@ -51,30 +73,57 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
 
+      - name: Check if pip cache exists
+        env:
+          # Increase this value to reset cache
+          CACHE_NUMBER: 1
+        run: |
+          PIP_CACHE_KEY="pip-3.9-${{ hashFiles('python/pyproject.toml', 'python/setup.py') }}-${{ env.CACHE_NUMBER }}"
+          PIP_CACHE="/cache/$PIP_CACHE_KEY"
+          echo "PIP_CACHE=$PIP_CACHE" >> "${GITHUB_ENV}"
+          if [[ -d $PIP_CACHE ]]; then
+            echo "Python cache found for key $PIP_CACHE_KEY"
+            echo $PIP_CACHE > .pip-cache
+            mkdir -p $HOME/.cache
+            ln -s $PIP_CACHE $HOME/.cache/pip
+          else
+            echo "Python cache not found for key $PIP_CACHE_KEY"
+          fi
+
       - name: Install Python 3.9
         uses: actions/setup-python@v4
         with:
           python-version: '3.9'
-          cache: 'pip'
-          cache-dependency-path: |
-            python/pyproject.toml
-            python/setup.py
-
-      - name: Read packages from cache
-        id: packages-cache
-        uses: actions/cache@v3
+
+      - name: Check if packages cache exists
         env:
           # Increase this value to reset cache
           CACHE_NUMBER: 1
-        with:
-          path: /home/runner/packages
-          key: packages-${{ hashFiles('scripts/compile-triton.sh', 'cmake/llvm-hash.txt') }}-${{ env.CACHE_NUMBER }}
+        run: |
+          PACKAGES_CACHE_KEY="packages-${{ hashFiles('scripts/compile-triton.sh', 'cmake/llvm-hash.txt') }}-${{ env.CACHE_NUMBER }}"
+          PACKAGES_CACHE="/cache/$PACKAGES_CACHE_KEY"
+          echo "PACKAGES_CACHE=$PACKAGES_CACHE" >> "${GITHUB_ENV}"
+          if [[ -d $PACKAGES_CACHE ]]; then
+            echo "Packages cache found for key $PACKAGES_CACHE_KEY"
+            echo $PACKAGES_CACHE > .packages-cache
+            ln -s $PACKAGES_CACHE $HOME/packages
+          else
+            echo "Packages cache not found for key $PACKAGES_CACHE_KEY"
+          fi
 
       - name: Build packages
-        if: steps.packages-cache.outputs.cache-hit != 'true'
+        if: ${{ hashFiles('.packages-cache') == '' }}
         run: |
           ./scripts/compile-triton.sh
 
+      - name: Save packages cache
+        if: ${{ hashFiles('.packages-cache') == '' }}
+        run: |
+          TMPDIR=/cache/${{ github.run_id }}-$RANDOM
+          mkdir $TMPDIR
+          cp -r $HOME/packages/* $TMPDIR/
+          mv $TMPDIR $PACKAGES_CACHE
+
       - name: Build Triton
         run: |
           cd python
@@ -111,3 +160,11 @@ jobs:
         run: |
           cd python/build/*cmake*
           ctest
+
+      - name: Save pip cache
+        if: ${{ hashFiles('.pip-cache') == '' }}
+        run: |
+          TMPDIR=/cache/${{ github.run_id }}-$RANDOM
+          mkdir $TMPDIR
+          cp -r $HOME/.cache/pip/* $TMPDIR/
+          mv $TMPDIR $PIP_CACHE