[llvm] [VPlan] Preserve IsSingleScalar for sunken predicated stores. (PR #184329)

[Julian Nagele via llvm-commits]

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@@ -4833,7 +4833,10 @@ void VPlanTransforms::sinkPredicatedStores(VPlan &Plan,
     VPValue *SelectedValue = Group[0]->getOperand(0);
     VPBuilder Builder(InsertBB, LastStore->getIterator());
 
+    bool IsSingleScalar = Group[0]->isSingleScalar();
     for (unsigned I = 1; I < Group.size(); ++I) {
+      assert(IsSingleScalar == Group[I]->isSingleScalar() &&
+             "all members in group must agree on IsSinglescalar");
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juliannagele wrote:

```suggestion
             "all members in group must agree on IsSingleScalar");
```

https://github.com/llvm/llvm-project/pull/184329