[llvm] [LV] Pre-commit test for sinking the recipe into vector early exit block. nfc (PR #177954)

[Florian Hahn via llvm-commits]

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@@ -0,0 +1,76 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 6
+; RUN: opt -S < %s -p loop-vectorize -force-vector-width=4 | FileCheck %s
+
+; Test that recipes used only in the early exit block can be sunk there.
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fhahn wrote:

```suggestion
; TODO: Recipe used only in the early exit block can be sunk there.
```

https://github.com/llvm/llvm-project/pull/177954