[llvm] [VPlan] Also duplicated scalar-steps when it enables sinking scalars. (PR #136021)

[via llvm-commits]

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@@ -163,18 +163,25 @@ static bool sinkScalarOperands(VPlan &Plan) {
       if (UI->getParent() == SinkTo)
         return true;
       NeedsDuplicating = UI->onlyFirstLaneUsed(SinkCandidate);
-      // We only know how to duplicate VPRecipeRecipes for now.
-      return NeedsDuplicating && isa<VPReplicateRecipe>(SinkCandidate);
+      // We only know how to duplicate VPRecipeRecipes and
+      // VPScalarIVStepsRecipes for now.
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ayalz wrote:

Optimized considering only first lane is used, as in turning replicate recipe to be uniform.

https://github.com/llvm/llvm-project/pull/136021