[llvm] [VPlan] Add VPPhiAccessors to provide interface for phi recipes (NFC) (PR #129388)

[Luke Lau via llvm-commits]

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@@ -1953,8 +2006,8 @@ class VPWidenPointerInductionRecipe : public VPWidenInductionRecipe,
 /// recipe is placed in an entry block to a (non-replicate) region, it must have
 /// exactly 2 incoming values, the first from the predecessor of the region and
 /// the second from the exiting block of the region.
-class VPWidenPHIRecipe : public VPSingleDefRecipe {
-  /// Name to use for the generated IR instruction for the widened phi.
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lukel97 wrote:

Was this comment meant to be removed? No strong opinion if was intentional, I think the variable name is descriptive enough

https://github.com/llvm/llvm-project/pull/129388