[llvm] [SLP][REVEC] Initial commits. (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:

Add the assertion for scalable types for now

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