riscv-software-src
diff --git a/‎.github/workflows/regress.yml
100644100755
+60 b/‎.github/workflows/regress.yml
100644100755
+60
diff --git a/‎.gitignore
+3 b/‎.gitignore
+3
diff --git a/‎.gitmodules
+4 b/‎.gitmodules
+4
diff --git a/‎Rakefile
+11 b/‎Rakefile
+11
@@ -17,12 +17,24 @@ jobs:
       - uses: actions/setup-python@v5
       - uses: pre-commit/[email protected]
   regress-smoke:
+    needs: build-llvm
     runs-on: ubuntu-latest
     env:
       SINGULARITY: 1
     steps:
       - name: Clone Github Repo Action
         uses: actions/checkout@v4
+      - name: Get current LLVM submodule commit SHA
+        id: get-llvm-sha
+        run: echo "LLVM_SHA=$(git ls-tree HEAD ext/llvm-project | awk '{print $3}')" >> $GITHUB_ENV
+      - name: Restore cache RISC-V JSON
+        id: cache-riscv
+        uses: actions/cache@v4
+        with:
+          path: ext/llvm-project/riscv.json
+          key: ${{ runner.os }}-riscv-json-${{ env.LLVM_SHA }}
+          restore-keys: |
+            ${{ runner.os }}-riscv-json-
       - name: singularity setup
         uses: ./.github/actions/singularity-setup
       - name: Run smoke
@@ -98,6 +110,54 @@ jobs:
         uses: ./.github/actions/singularity-setup
       - name: Generate extension PDF
         run: ./do gen:profile_release_pdf[Mock]
+  build-llvm:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out repository (no submodules, shallow fetch)
+        uses: actions/checkout@v4
+        with:
+          submodules: false
+          fetch-depth: 1
+      - name: Get current LLVM submodule commit SHA
+        id: get-llvm-sha
+        run: echo "LLVM_SHA=$(git ls-tree HEAD ext/llvm-project | awk '{print $3}')" >> $GITHUB_ENV
+      - name: Cache RISC-V JSON
+        id: cache-riscv
+        uses: actions/cache@v4
+        with:
+          path: ext/llvm-project/riscv.json
+          key: ${{ runner.os }}-riscv-json-${{ env.LLVM_SHA }}
+          restore-keys: |
+            ${{ runner.os }}-riscv-json-
+      - name: Initialize LLVM submodule (shallow + sparse)
+        if: ${{ steps.cache-riscv.outputs.cache-hit != 'true' }}
+        run: |
+          git submodule sync --recursive
+          git submodule update --init --recursive --depth=1 ext/llvm-project
+
+      - name: Check for required directories and files
+        if: ${{ steps.cache-riscv.outputs.cache-hit != 'true' }}
+        run: |
+          ls -l ext/llvm-project/llvm/include
+          ls -l ext/llvm-project/llvm/lib/Target/RISCV
+          ls -l ext/llvm-project/llvm/lib/Target/RISCV/RISCV.td
+      - name: Configure and build llvm-tblgen
+        if: ${{ steps.cache-riscv.outputs.cache-hit != 'true' }}
+        run: |
+          cmake -S ext/llvm-project/llvm -B ext/llvm-project/build -DCMAKE_BUILD_TYPE=Release
+          cmake --build ext/llvm-project/build --target llvm-tblgen
+      - name: Generate RISC-V JSON
+        if: ${{ steps.cache-riscv.outputs.cache-hit != 'true' }}
+        run: |
+          chmod +x ./ext/llvm-project/build/bin/llvm-tblgen
+          ./ext/llvm-project/build/bin/llvm-tblgen \
+            -I ext/llvm-project/llvm/include \
+            -I ext/llvm-project/llvm/lib/Target/RISCV \
+            ext/llvm-project/llvm/lib/Target/RISCV/RISCV.td \
+            --dump-json \
+            -o ext/llvm-project/riscv.json
+      - name: Show riscv.json output
+        run: ls -l ext/llvm-project/riscv.json
   regress-gen-go:
     runs-on: ubuntu-latest
     env:
 
@@ -16,5 +16,8 @@ gen
 node_modules
 _site
 images
+__pycache__/
+*.pyc
+.pytest_cache/
 *.bak
 *.log
@@ -7,6 +7,10 @@
 [submodule "ext/riscv-isa-manual"]
 	path = ext/riscv-isa-manual
 	url = https://github.com/riscv/riscv-isa-manual
+[submodule "ext/llvm-project"]
+	path = ext/llvm-project
+	url = https://github.com/llvm/llvm-project.git
+	branch = main
 [submodule "ext/riscv-tests"]
 	path = ext/riscv-tests
 	url = https://github.com/riscv-software-src/riscv-tests.git
@@ -157,6 +157,15 @@ namespace :serve do
 end
 
 namespace :test do
+
+  # "Run the cross-validation against LLVM"
+  task :llvm do
+      begin
+        sh "#{$root}/.home/.venv/bin/python3 -m pytest ext/auto-inst/test_parsing.py -v"
+      rescue => e
+        raise unless e.message.include?("status (5)") # don't fail on skipped tests
+    end
+  end
   # "Run the IDL compiler test suite"
   task :idl_compiler do
     t = Minitest::TestTask.new(:lib_test)
@@ -430,6 +439,8 @@ namespace :test do
     Rake::Task["test:idl"].invoke
     puts "UPDATE: Running test:inst_encodings"
     Rake::Task["test:inst_encodings"].invoke
+    puts "UPDATE: Running test:llvm"
+    Rake::Task["test:llvm"].invoke
     puts "UPDATE: Done test:smoke"
   end