[llvm] [SLP] SLP's copyable elements based upon Main/Alt operations. (PR #124242)

[Alexey Bataev via llvm-commits]

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@@ -816,6 +854,9 @@ class InstructionsState {
   Instruction *MainOp = nullptr;
   Instruction *AltOp = nullptr;
 
+  /// True if alterative operation is copy instruction.
+  bool IsAltOpCopy = false;
+
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alexey-bataev wrote:

I don't think you need this flag. Instead, InstructionsState should be initialized for the homogeneous instructions, not heterogeneous. And build the instruction, using the correctly built operands for the node

https://github.com/llvm/llvm-project/pull/124242