[clang] [CIR] Add CIR vtable attribute (PR #154415)

[Andy Kaylor via cfe-commits]

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@@ -496,6 +496,46 @@ def CIR_GlobalViewAttr : CIR_Attr<"GlobalView", "global_view", [
   }];
 }
 
+//===----------------------------------------------------------------------===//
+// VTableAttr
+//===----------------------------------------------------------------------===//
+
+def VTableAttr : CIR_Attr<"VTable", "vtable", [TypedAttrInterface]> {
+  let summary = "Represents a C++ vtable";
+  let description = [{
+    Wraps a #cir.const_record containing vtable data.
+
+    Example:
+    ```
+    cir.global linkonce_odr @_ZTV1B = #cir.vtable<<
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andykaylor wrote:

There seem to be extra brackets in this example, which may be making it harder to understand.

https://github.com/llvm/llvm-project/pull/154415