add CI back

.github/workflows/enzyme-ci.yml

@@ -0,0 +1,38 @@
+name: Rust CI
+
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+    branches:
+    - master
+  merge_group:
+
+jobs:
+  build:
+    name: Rust Integration CI LLVM ${{ matrix.llvm }} ${{ matrix.build }} ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [openstack22]
+
+    timeout-minutes: 600
+    steps:
+      - name: checkout the source code
+        uses: actions/checkout@v3
+        with:
+          fetch-depth: 2
+      - name: build
+        run: |
+          mkdir build
+          cd build
+          ../configure --enable-llvm-link-shared --enable-llvm-plugins --enable-llvm-enzyme --release-channel=nightly --enable-llvm-assertions --enable-lld --enable-option-checking --enable-ninja --disable-docs
+          ../x.py build --stage 1 library/std library/proc_macro library/test tools/rustdoc
+          rustup toolchain link enzyme `pwd`/build/`rustup target list --installed`/stage1
+          rustup toolchain install nightly # enables -Z unstable-options
+      - name: test
+        run: |
+          cargo +enzyme test --examples