[llvm] [SLP] NFC. Replace MainOp and AltOp in TreeEntry with InstructionsState. (PR #120198)

[Alexey Bataev via llvm-commits]

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@@ -3325,9 +3327,7 @@ class BoUpSLP {
     /// reordering of operands during buildTree_rec() and vectorizeTree().
     SmallVector<ValueList, 2> Operands;
 
-    /// The main/alternate instruction.
-    Instruction *MainOp = nullptr;
-    Instruction *AltOp = nullptr;
+    InstructionsState S = InstructionsState::invalid();
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alexey-bataev wrote:

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https://github.com/llvm/llvm-project/pull/120198