[llvm] [SLP] NFC. Refactor getEntryCost and isReverseOrder usage. (PR #119680)

[Han-Kuan Chen via llvm-commits]

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@@ -11003,9 +11004,8 @@ BoUpSLP::getEntryCost(const TreeEntry *E, ArrayRef<Value *> VectorizedVals,
   }
   InstructionCost CommonCost = 0;
   SmallVector<int> Mask;
-  bool IsReverseOrder = isReverseOrder(E->ReorderIndices);
-  if (!E->ReorderIndices.empty() &&
-      (E->State != TreeEntry::StridedVectorize || !IsReverseOrder)) {
+  if (!E->ReorderIndices.empty() && (E->State != TreeEntry::StridedVectorize ||
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HanKuanChen wrote:

Yes.
`IsReverseOrder` is replaced with `isReverseOrder`.

https://github.com/llvm/llvm-project/pull/119680