[clang] [CIR]lAdd name for function type in vtable (PR #163839)

[Andy Kaylor via cfe-commits]

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@@ -946,8 +946,7 @@ const char *vTableClassNameForType(const CIRGenModule &cgm, const Type *ty) {
 
   case Type::FunctionNoProto:
   case Type::FunctionProto:
-    cgm.errorNYI("VTableClassNameForType: __function_type_info");
-    break;
+    return "__ZTSN10__cxxabiv120__function_type_infoE";
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andykaylor wrote:

Yes. `__ZTSN10__cxxabiv120__function_type_infoE` is the _typeinfo name for `__cxxabiv1::__function_type_info` but what we need here is the vtable.

https://github.com/llvm/llvm-project/pull/163839