[llvm] [VPlan] Support struct return types for widen intrinsics (NFC). (PR #165218)

[Benjamin Maxwell via llvm-commits]

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@@ -1802,8 +1811,20 @@ static InstructionCost getCostForIntrinsics(Intrinsic::ID ID,
     Arguments.push_back(V);
   }
 
-  Type *ScalarRetTy = Ctx.Types.inferScalarType(&R);
-  Type *RetTy = VF.isVector() ? toVectorizedTy(ScalarRetTy, VF) : ScalarRetTy;
+  Type *RetTy = Ctx.Types.inferScalarType(&R);
+
+  if (VF.isVector() && RetTy->isStructTy()) {
+    auto *StructTy = cast<StructType>(RetTy);
+    SmallVector<Type *> Tys;
+    for (unsigned I = 0, E = StructTy->getNumElements(); I != E; ++I) {
+      Type *ElementTy = StructTy->getStructElementType(I);
+      if (!isVectorIntrinsicWithStructReturnScalarAtField(ID, I))
+        ElementTy = toVectorizedTy(ElementTy, VF);
+      Tys.push_back(ElementTy);
+    }
+    RetTy = StructType::get(StructTy->getContext(), Tys);
+  } else if (VF.isVector())
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MacDue wrote:

Duplicate code (which is why this should be handled by the helper). 

https://github.com/llvm/llvm-project/pull/165218