[llvm] [SLP]Represent SLP graph as a tree (PR #126771)

[Luke Lau via llvm-commits]

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@@ -5951,6 +5985,67 @@ static void combineOrders(MutableArrayRef<unsigned> Order,
   }
 }
 
+bool BoUpSLP::isProfitableToReorder() const {
+  constexpr unsigned TinyVF = 2;
+  constexpr unsigned TinyTree = 10;
+  if (VectorizableTree.size() <= TinyTree)
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lukel97 wrote:

How come this is different from `slp-min-tree-size`/`MinTreeSize`?

https://github.com/llvm/llvm-project/pull/126771