[llvm] [LV] Support binary and unary operations with EVL-vectorization (PR #93854)

[Florian Hahn via llvm-commits]

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@@ -1296,6 +1297,56 @@ void VPlanTransforms::addActiveLaneMask(
     HeaderMask->replaceAllUsesWith(LaneMask);
 }
 
+/// Replace recipes with their EVL variants.
+static void transformRecipestoEVLRecipes(VPlan &Plan, VPValue &EVL) {
+  DenseSet<VPRecipeBase *> ToRemove;
+
+  ReversePostOrderTraversal<VPBlockDeepTraversalWrapper<VPBlockBase *>> RPOT(
+      Plan.getEntry());
+  DenseSet<VPValue *> HeaderMasks = collectAllHeaderMasks(Plan);
+  for (VPBasicBlock *VPBB :
+       reverse(VPBlockUtils::blocksOnly<VPBasicBlock>(RPOT))) {
+    // The recipes in the block are processed in reverse order, to catch chains
+    // of dead recipes.
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fhahn wrote:

Is this accurate? How do we get chains of dead recipes? 

https://github.com/llvm/llvm-project/pull/93854