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

[Kolya Panchenko via llvm-commits]

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@@ -1652,6 +1694,29 @@ void VPReductionRecipe::print(raw_ostream &O, const Twine &Indent,
     O << " (with final reduction value stored in invariant address sank "
          "outside of loop)";
 }
+
+void VPReductionEVLRecipe::print(raw_ostream &O, const Twine &Indent,
+                                 VPSlotTracker &SlotTracker) const {
+  O << Indent << "REDUCE ";
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nikolaypanchenko wrote:

Better to have more explicit naming here. For example `VP-REDUCE`

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