[llvm] [LoopVectorize] Add test case for minloc reduction (PR #141556)

[Florian Hahn via llvm-commits]

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@@ -0,0 +1,84 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -passes=loop-vectorize -S %s | FileCheck %s --check-prefix=CHECK-REV-MIN
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fhahn wrote:

This will need something like `-force-vector-width=4` to make sure this gets vectorized if possible.
```suggestion
; RUN: opt -passes=loop-vectorize -force-vector-width=4 -S %s | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/141556