[llvm] [NFC][LoopVectorize] Introduce new getEstimatedRuntimeVF function (PR #116247)

[Hari Limaye via llvm-commits]

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@@ -4291,6 +4291,21 @@ getVScaleForTuning(const Loop *L, const TargetTransformInfo &TTI) {
   return TTI.getVScaleForTuning();
 }
 
+/// This functions attempts to return a value that represents the vectorization
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hazzlim wrote:

Just a small nit:
```suggestion
/// This function attempts to return a value that represents the vectorization
```

https://github.com/llvm/llvm-project/pull/116247