[llvm] [SLP][REVEC] Make ShuffleCostEstimator and ShuffleInstructionBuilder can vectorize vector instructions. (PR #99606)

[Alexey Bataev via llvm-commits]

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@@ -8800,13 +8815,17 @@ class BoUpSLP::ShuffleCostEstimator : public BaseShuffleAnalysis {
       // Shuffle single vector.
       ExtraCost += GetValueMinBWAffectedCost(V1);
       CommonVF = cast<FixedVectorType>(V1->getType())->getNumElements();
+      if (auto *VecTy = dyn_cast<FixedVectorType>(ScalarTy))
+        CommonVF /= VecTy->getNumElements();
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alexey-bataev wrote:

Anyway better to have assertion here

https://github.com/llvm/llvm-project/pull/99606