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

[Alexey Bataev via llvm-commits]

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@@ -8728,6 +8744,16 @@ class BoUpSLP::ShuffleCostEstimator : public BaseShuffleAnalysis {
       }
       return TTI::TCC_Free;
     };
+    auto GetVF = [&](Value *V) {
+      unsigned VNumElements =
+          cast<FixedVectorType>(V->getType())->getNumElements();
+      assert(VNumElements > ScalarTyNumElements &&
+             VNumElements % ScalarTyNumElements == 0);
+      // V1 and V2 would be the argument of shufflevector.
+      // The maximum index of Mask should be (VNumElements * 2) - 1.
+      assert(VNumElements <= 2 * ScalarTyNumElements * Mask.size());
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alexey-bataev wrote:

Add assertion message

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