[llvm] [SLP][REVEC] Initial commits. (PR #98269)

[Han-Kuan Chen via llvm-commits]

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@@ -11807,10 +11824,10 @@ class BoUpSLP::ShuffleInstructionBuilder final : public BaseShuffleAnalysis {
   Value *castToScalarTyElem(Value *V,
                             std::optional<bool> IsSigned = std::nullopt) {
     auto *VecTy = cast<VectorType>(V->getType());
-    if (VecTy->getElementType() == ScalarTy)
+    if (VecTy->getElementType() == ScalarTy->getScalarType())
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HanKuanChen wrote:

Possible. They may have different number of elements.
The number of elements for `VecTy` is a multiple of `ScalarTy`.

https://github.com/llvm/llvm-project/pull/98269