[llvm] [Github] Add initial version of precommit checks (PR #80951)

[Tom Stellard via llvm-commits]

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@@ -0,0 +1,47 @@
+name: "Precommit tests"
+
+permissions:
+  contents: read
+
+on:
+  pull_request:
+    branches:
+      - main
+    paths:
+      - '.github/workflows/precommit.yaml'
+      - 'llvm/**'
+
+jobs:
+  build-llvm:
+    name: "Build and test LLVM"
+    runs-on: ubuntu-latest
+    container:
+      image: ghcr.io/llvm/ci-ubuntu-22.04:latest
+    steps:
+      - name: Fetch LLVM sources
+        uses: actions/checkout at v4
+        with:
+          fetch-depth: 1
+      - name: Setup ccache
+        uses: hendrikmuhs/ccache-action at v1
+        with:
+          max-size: 500M
+          variant: sccache
+          key: precommit-linux
----------------
tstellar wrote:

How well do you think the caching will work if we aren't running this job post-commit.

https://github.com/llvm/llvm-project/pull/80951