[llvm] [Vectorizer] precommit test for miscompilation (PR #120731)

[Florian Hahn via llvm-commits]

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@@ -0,0 +1,107 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
+; RUN: opt -passes=loop-vectorize -force-vector-width=4 -enable-vplan-native-path -S %s | FileCheck %s
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fhahn wrote:

```suggestion
; RUN: opt -passes=loop-vectorize -force-vector-width=4 -S %s | FileCheck %s
```

no nested loops, so no the 'native' path isn't used.

https://github.com/llvm/llvm-project/pull/120731