[llvm] [UniformityAnalysis] Propagate label to cycle exit blocks (PR #216296)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,112 @@
+; RUN: opt -mtriple amdgcn-unknown-amdhsa -passes='print<uniformity>' -disable-output %s 2>&1 | FileCheck %s
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arsenm wrote:

```suggestion
; RUN: opt -mtriple=amdgpu7.00-unknown-amdhsa -passes='print<uniformity>' -disable-output %s 2>&1 | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/216296