[clang] [CIR] Upstream splat op for VectorType (PR #139827)

[Henrich Lauko via cfe-commits]

================
@@ -2275,4 +2275,36 @@ def VecTernaryOp : CIR_Op<"vec.ternary",
   let hasFolder = 1;
 }
 
+//===----------------------------------------------------------------------===//
+// VecSplatOp
+//===----------------------------------------------------------------------===//
+
+def VecSplatOp : CIR_Op<"vec.splat", [Pure,
+  TypesMatchWith<"type of 'value' matches element type of 'result'", "result",
+                 "value", "cast<VectorType>($_self).getElementType()">]> {
----------------
xlauko wrote:

```suggestion
                 "value", "$_self.getElementType()">]> {
```

https://github.com/llvm/llvm-project/pull/139827