[llvm] [UTC] Support to test annotated IR (PR #165419)

[Kunqiu Chen via llvm-commits]

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@@ -1,5 +1,5 @@
-; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt -passes=print-predicateinfo < %s 2>&1 | FileCheck %s
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-inst-comments
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Camsyn wrote:

No, it wouldn't.
It's the mismatched variable regex `r"(\s*)(?:%([\w$.-]+?))([,\s\(\)\}]|\Z)"` that causes the missed capture of the labels in `... , %label]`.
See this exmpale:
<img width="873" height="261" alt="image" src="https://github.com/user-attachments/assets/1307f0d7-4164-4136-819c-3b7795a1f3d0" />

https://github.com/llvm/llvm-project/pull/165419