[llvm] [SLP] Fix PoisonValue in the argument VL of setOperand. (PR #118949)

[Alexey Bataev via llvm-commits]

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@@ -3338,14 +3335,13 @@ class BoUpSLP {
       copy(OpVL, Operands[OpIdx].begin());
     }
 
-    /// Set this bundle's operand from \p VL.
-    void setOperand(ArrayRef<Value *> VL, const BoUpSLP &R,
+    /// Set this bundle's operand from Scalars.
+    void setOperand(Instruction *VL0, const BoUpSLP &R,
                     bool RequireReorder = false) {
-      VLOperands Ops(VL, R);
+      VLOperands Ops(Scalars, VL0, R);
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alexey-bataev wrote:

Instead of passing `VL0` here, I think you can safely use MainOp member instruction

https://github.com/llvm/llvm-project/pull/118949