[llvm] [VPlan] Handle live-in extend operands in partial reduction ::computeCost (PR #163175)

[Sander de Smalen via llvm-commits]

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@@ -329,7 +329,12 @@ VPPartialReductionRecipe::computeCost(ElementCount VF,
   // recipe.
   auto HandleWiden = [&](VPWidenRecipe *Widen) {
     if (match(Widen, m_Sub(m_ZeroInt(), m_VPValue(Op)))) {
-      Widen = dyn_cast<VPWidenRecipe>(Op->getDefiningRecipe());
+      Widen = dyn_cast<VPWidenRecipe>(Op);
+      if (!Widen) {
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sdesmalen-arm wrote:

I left a comment yesterday on @SamTebbs33' patch that took these changes: https://github.com/llvm/llvm-project/pull/147302#discussion_r2444983975


https://github.com/llvm/llvm-project/pull/163175