[llvm] [Github][RFC] Add workflow to diff codegen on llvm-test-suite (PR #190010)

[Luke Lau via llvm-commits]

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@@ -0,0 +1,136 @@
+# When /test-suite is commented on a PR, checks out the PR, builds clang and
+# then the test-suite in several configurations. It then checks out the base of
+# the PR, builds clang and the test-suite again, and then uploads the diff of
+# the codegen.
+
+name: Diff test-suite codegen
+
+on:
+  issue_comment:
+    types:
+      - created
+
+jobs:
+  test-suite:
+    name: Build and diff
+    runs-on: ubuntu-24.04
+    permissions:
+      pull-requests: write
+    if: >-
+      !startswith(github.event.comment.body, '<!--IGNORE-->') &&
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lukel97 wrote:

I copied this from issue-release-workflow.yml which has the `/cherry-pick` command. I'm not actually sure what it's for. But I figured we should probably just restrict it to comments that start with a slash command anyway so removed it in aa01aa3c59658625fec95734448824439636aac3

https://github.com/llvm/llvm-project/pull/190010