[clang] [CIR] Function calls with aggregate arguments and return values (PR #143377)

[Andy Kaylor via cfe-commits]

================
@@ -240,6 +284,43 @@ void AggExprEmitter::emitNullInitializationToLValue(mlir::Location loc,
   cgf.emitNullInitialization(loc, lv.getAddress(), lv.getType());
 }
 
+void AggExprEmitter::VisitCallExpr(const CallExpr *e) {
+  if (e->getCallReturnType(cgf.getContext())->isReferenceType()) {
+    llvm_unreachable("NYI");
----------------
andykaylor wrote:

```suggestion
    cgf.cgm.errorNYI(e->getSourceRounge(), "reference return type");
    return;
```

https://github.com/llvm/llvm-project/pull/143377