[clang] [CIR] Implement builtin extractf (PR #170427)

[Henrich Lauko via cfe-commits]

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@@ -266,6 +266,16 @@ class CIR_VectorTypeOf<list<Type> types, string summary = "">
             "vector of " # CIR_TypeSummaries<types>.value,
             summary)>;
 
+class CIR_VectorOf<Type T> : CIR_ConfinedType<
+  CIR_AnyVectorType,
+  [CIR_ElementTypePred<T.predicate>],
+  "CIR vector of " # T.summary>;
+
+// Type constraint accepting a either a type T or a vector of type T
+// Mimicking LLVMIR's LLVM_ScalarOrVectorOf
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xlauko wrote:

```suggestion
```

https://github.com/llvm/llvm-project/pull/170427