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

[Kunqiu Chen via llvm-commits]

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@@ -13,34 +13,41 @@ define i32 @main() {
 ; CHECK-LABEL: @main(
 ; CHECK-NEXT:    store i32 6, ptr @e, align 4
 ; CHECK-NEXT:    br label [[TMP1:%.*]]
-; CHECK:         [[TMP2:%.*]] = load i32, ptr @d, align 4
+; CHECK:       1:
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Camsyn wrote:

> Maybe the script regex for labels expected a leading alphabetical character?

In fact, this change was not introduced by this PR, and I don't know why the label check here is 1.

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