[llvm] [SLP] NFC. Use InstructionsState::valid if users just want to know whether VL has same opcode. (PR #120217)

[Alexey Bataev via llvm-commits]

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@@ -15059,7 +15061,7 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E, bool PostponedPHIs) {
   auto *VecTy = getWidenedType(ScalarTy, E->Scalars.size());
   if (E->isGather()) {
     // Set insert point for non-reduction initial nodes.
-    if (E->getMainOp() && E->Idx == 0 && !UserIgnoreList)
+    if (E->getMainOp() != nullptr && E->Idx == 0 && !UserIgnoreList)
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alexey-bataev wrote:

Restore original code

https://github.com/llvm/llvm-project/pull/120217