[llvm] [SLP][NFC] Extract VectorizableTree into own ForestTree class (PR #222805)

[Alexey Bataev via llvm-commits]

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@@ -14424,6 +14927,7 @@ class BoUpSLP::ShuffleCostEstimator : public BaseShuffleAnalysis {
   InstructionCost Cost = 0;
   SmallDenseSet<Value *> VectorizedVals;
   BoUpSLP &R;
+  ForestTree &FT;
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alexey-bataev wrote:

Unused

https://github.com/llvm/llvm-project/pull/222805