[llvm] [Scalarizer][DirectX] support structs return types (PR #111569)

[Farzon Lotfi via llvm-commits]

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@@ -699,6 +728,18 @@ bool ScalarizerVisitor::splitCall(CallInst &CI) {
   if (isVectorIntrinsicWithOverloadTypeAtArg(ID, -1))
     Tys.push_back(VS->SplitTy);
 
+  if (AreAllVectors) {
+    Type *PrevType = CallType->getContainedType(0);
+    Type *CallType = CI.getType();
+    for (unsigned I = 1; I < CallType->getNumContainedTypes(); I++) {
+      Type *CurrType = cast<FixedVectorType>(CallType->getContainedType(I));
+      if (PrevType != CurrType) {
+        std::optional<VectorSplit> CurrVS = getVectorSplit(CurrType);
+        Tys.push_back(CurrVS->SplitTy);
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farzonl wrote:

I’ve never seen the `if (Split.NumPacked >= NumElems)` case be true.  But sure you are right. We could add an assert or return false?

https://github.com/llvm/llvm-project/pull/111569