[llvm] [VPlan] Support VPReverseVectorPointer in DataWithEVL vectorization (PR #113667)

[Florian Hahn via llvm-commits]

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@@ -1462,15 +1462,22 @@ static void transformRecipestoEVLRecipes(VPlan &Plan, VPValue &EVL) {
         assert(OrigMask && "Unmasked recipe when folding tail");
         return HeaderMask == OrigMask ? nullptr : OrigMask;
       };
+      auto SetEVLForReversePointer = [&EVL](VPValue *V) -> void {
+        if (auto *R = dyn_cast_if_present<VPReverseVectorPointerRecipe>(
+                V->getDefiningRecipe()))
+          R->setOperand(1, &EVL);
+      };
 
       VPRecipeBase *NewRecipe =
           TypeSwitch<VPRecipeBase *, VPRecipeBase *>(CurRecipe)
               .Case<VPWidenLoadRecipe>([&](VPWidenLoadRecipe *L) {
                 VPValue *NewMask = GetNewMask(L->getMask());
+                SetEVLForReversePointer(L->getAddr());
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fhahn wrote:

Would it be better to set EVL for all `VPReverseVectorPointerRecipe`? There could be other memory recipes in the future , e.g. interleave groups

https://github.com/llvm/llvm-project/pull/113667