[llvm] [VPlan] Add VPValue for VF, use it for VPWidenIntOrFpInductionRecipe. (PR #95305)

[via llvm-commits]

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@@ -3408,6 +3416,9 @@ class VPlan {
   /// The vector trip count.
   VPValue &getVectorTripCount() { return VectorTripCount; }
 
+  /// Returns the VF of the vector loop region.
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ayalz wrote:

Why pointer rather than reference, as in VFxUF, null is not used/returned.

https://github.com/llvm/llvm-project/pull/95305