[llvm] [VPlan] Implement interleaving as VPlan-to-VPlan transform. (PR #95842)

[via llvm-commits]

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@@ -2858,6 +2871,9 @@ class VPWidenCanonicalIVRecipe : public VPSingleDefRecipe {
   /// step = <VF*UF, VF*UF, ..., VF*UF>.
   void execute(VPTransformState &State) override;
 
+  /// Return the part associated with this widened IV.
+  unsigned getPartForRecipe() const;
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ayalz wrote:

```suggestion
  /// Return the unroll part associated with this widened IV.
  unsigned getUnrollPartForRecipe() const;
```

https://github.com/llvm/llvm-project/pull/95842