[llvm] [SLP][REVEC] Make SLP support revectorization (-slp-revec) and add simple test. (PR #98269)

[Alexey Bataev via llvm-commits]

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@@ -227,13 +231,24 @@ static const unsigned MaxPHINumOperands = 128;
 /// avoids spending time checking the cost model and realizing that they will
 /// be inevitably scalarized.
 static bool isValidElementType(Type *Ty) {
+  // TODO: Support ScalableVectorType.
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alexey-bataev wrote:

Why? We do not support scalable types in SLP vectorizer, so it should be fine (at least for now) that SLP does not work with scalable typesбгт less it crashes the compiler. The crashes should be fixed.

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