[llvm] [LV][EVL] Support in-loop reduction using tail folding with EVL. (PR #90184)

[Mel Chen via llvm-commits]

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@@ -2102,20 +2103,26 @@ class VPInterleaveRecipe : public VPRecipeBase {
 /// a vector operand into a scalar value, and adding the result to a chain.
 /// The Operands are {ChainOp, VecOp, [Condition]}.
 class VPReductionRecipe : public VPSingleDefRecipe {
+protected:
   /// The recurrence decriptor for the reduction in question.
   const RecurrenceDescriptor &RdxDesc;
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Mel-Chen wrote:

006730302584316cfba1722453259aadf19aa7d9
We can have it, but will increase some getter calls in `VPReductionEVLRecipe`.

https://github.com/llvm/llvm-project/pull/90184