Build PAPI based benchmarks on CI when possible

Author: Shimuuar

.github/workflows/ci.yml

@@ -74,6 +74,12 @@ jobs:
         path: ${{ steps.setup-haskell-cabal.outputs.cabal-store }}
         key: ${{ runner.os }}-${{ matrix.ghc }}--${{ github.Shah }}
     # ----------------
+    - name: "Install PAPI"
+      run: |
+        sudo apt-get install -y libpapi-dev
+        echo FLAG_PAPI=-fBenchPAPI >> "$GITHUB_ENV"
+      if: matrix.os == 'ubuntu-latest'
+    # ----------------
     - name: Versions
       run: |
         cabal -V
@@ -97,7 +103,7 @@ jobs:
       run: |
         if [ "${{ matrix.skip-test  }}" == "" ]; then FLAG_TEST=--enable-test; fi
         if [ "${{ matrix.skip-bench }}" == "" ]; then FLAG_BENCH=--enable-benchmarks; fi
-        cabal configure $FLAG_TEST $FLAG_BENCH --flags='${{matrix.flags}}'
+        cabal configure $FLAG_PAPI $FLAG_TEST $FLAG_BENCH --flags='${{matrix.flags}}'
         cabal build all --write-ghc-environment-files=always
     # ----------------
     - name: Test