[llvm] [LV] Add initial support for vectorizing literal struct return values (PR #109833)

[Benjamin Maxwell via llvm-commits]

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@@ -0,0 +1,53 @@
+//===----------- VectorUtils.h -  Vector type utility functions -*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/IR/DerivedTypes.h"
+
+namespace llvm {
+
+/// A helper function for converting Scalar types to vector types. If
+/// the incoming type is void, we return void. If the EC represents a
+/// scalar, we return the scalar type.
+inline Type *ToVectorTy(Type *Scalar, ElementCount EC) {
+  if (Scalar->isVoidTy() || Scalar->isMetadataTy() || EC.isScalar())
+    return Scalar;
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MacDue wrote:

This is my bad :sweat_smile:, but the two `ToVectorTy` helpers already exist upstream. I just moved them next to my new helpers (`ToWideTy`, `ToNarrowTy`, etc.). So, I don't think I should change their behavior as part of this PR.

https://github.com/llvm/llvm-project/pull/109833