Cache Spike and Sail in CI (#526)

* Cache Spike in CI

* Cache Sail in CI

Author: jordancarlin

.github/workflows/test.yml

@@ -43,6 +43,7 @@ jobs:
           sudo apt-get install -y python3 python3-pip python3-venv
           sudo apt-get install -y gcc git autoconf automake libtool curl make unzip
           sudo apt-get install autoconf automake autotools-dev curl python3 python3-pip libmpc-dev libmpfr-dev libgmp-dev gawk build-essential bison flex texinfo gperf libtool patchutils bc zlib1g-dev libexpat-dev ninja-build git cmake libglib2.0-dev libslirp-dev pkg-config
+          sudo apt-get install device-tree-compiler libboost-regex-dev libboost-system-dev
           pip3 install git+https://github.com/riscv/riscof.git
       
       - name: Build RISCV-GNU Toolchain (${{ matrix.xlen }} bit)
@@ -61,27 +62,73 @@ jobs:
         run: |
           cd riscv-ctg
           pip3 install --editable .
-      
+
+      - name: Get Latest Spike Commit
+        run: |
+              SPIKE_HASH=$(git ls-remote https://github.com/riscv/riscv-isa-sim.git HEAD | awk '{ print $1}')
+              echo "SPIKE_HASH=$SPIKE_HASH" >> "$GITHUB_ENV"
+
+      - name: Restore cached Spike
+        id: cache-spike-restore
+        uses: actions/cache/restore@v4
+        with:
+          path: ${{ github.workspace }}/spike
+          key: spike-${{ env.SPIKE_HASH }}-RV${{ matrix.xlen }}
+
       - name: Install Spike
+        if: steps.cache-spike-restore.outputs.cache-hit != 'true'
         run: |
           git clone https://github.com/riscv/riscv-isa-sim.git
-          sudo apt-get install device-tree-compiler libboost-regex-dev libboost-system-dev
           cd riscv-isa-sim
           mkdir build
           cd build
-          ../configure --prefix=$GITHUB_WORKSPACE/riscv64
+          ../configure --prefix=$GITHUB_WORKSPACE/spike
           make -j$(nproc)
-          sudo make install
-          echo $GITHUB_WORKSPACE/riscv64/bin >> $GITHUB_PATH      
+          make install
+
+      - name: Save cached Spike
+        if: steps.cache-spike-restore.outputs.cache-hit != 'true'
+        id: cache-spike-save
+        uses: actions/cache/save@v4
+        with:
+          path: ${{ github.workspace }}/spike
+          key: ${{ steps.cache-spike-restore.outputs.cache-primary-key }}
+
+      - name: Get Latest Sail Commit
+        run: |
+              SAIL_HASH=$(git ls-remote https://github.com/riscv/sail-riscv.git HEAD | awk '{ print $1}')
+              echo "SAIL_HASH=$SAIL_HASH" >> "$GITHUB_ENV"
+
+      - name: Restore cached Sail
+        id: cache-sail-restore
+        uses: actions/cache/restore@v4
+        with:
+          path: ${{ github.workspace }}/sail
+          key: sail-${{ env.SAIL_HASH }}-RV${{ matrix.xlen }}
 
       - name: Install Sail
+        if: steps.cache-sail-restore.outputs.cache-hit != 'true'
         run: |
           sudo mkdir -p /usr/local
           curl --location https://github.com/rems-project/sail/releases/download/0.18-linux-binary/sail.tar.gz | sudo tar xvz --directory=/usr/local --strip-components=1
           git clone https://github.com/riscv/sail-riscv.git
           cd sail-riscv
           ARCH=RV${{ matrix.xlen }} make
-          echo $PWD/c_emulator >> $GITHUB_PATH            
+          mkdir -p $GITHUB_WORKSPACE/sail
+          mv c_emulator/riscv_sim_RV${{ matrix.xlen }} $GITHUB_WORKSPACE/sail/riscv_sim_RV${{ matrix.xlen }}
+
+      - name: Save cached Sail
+        if: steps.cache-sail-restore.outputs.cache-hit != 'true'
+        id: cache-sail-save
+        uses: actions/cache/save@v4
+        with:
+          path: ${{ github.workspace }}/sail
+          key: ${{ steps.cache-sail-restore.outputs.cache-primary-key }}
+
+      - name: Set PATH
+        run: |
+              echo $GITHUB_WORKSPACE/spike/bin >> $GITHUB_PATH
+              echo $GITHUB_WORKSPACE/sail >> $GITHUB_PATH
       
       - name: Config and run riscof for RV${{ matrix.xlen }}
         run: |