[FIFO] remove stitched IP and rtlsim metadata after FIFO sizing

src/finn/transformation/fpgadataflow/set_fifo_depths.py

@@ -439,6 +439,8 @@ def apply(self, model):
                 sim = verilator_fifosim(model, n_inferences)
             elif backend in ["xsi", "pyxsi"]:
                 sim = xsi_fifosim(model, n_inferences)
+            else:
+                assert False, f"Unrecognized backend for InsertAndSetFIFODepths: {backend}"
 
         for ind, node in enumerate(fifo_nodes):
             maxcount_name = "maxcount_%d" % ind
@@ -494,6 +496,15 @@ def apply(self, model):
         # remove shallow FIFOs
         model = model.transform(RemoveShallowFIFOs())
 
+        # clean up references to stitched IP and rtlsim objects
+        # (the stitched IP needs to be re-done after FIFO sizing)
+        model.set_metadata_prop("rtlsim_trace", "")
+        model.set_metadata_prop("rtlsim_so", "")
+        model.set_metadata_prop("vivado_stitch_proj", "")
+        model.set_metadata_prop("wrapper_filename", "")
+        model.set_metadata_prop("vivado_stitch_vlnv", "")
+        model.set_metadata_prop("vivado_stitch_ifnames", "")
+
         # reflect final values in attributes
         for node in model.graph.node:
             if not node.op_type.startswith("StreamingFIFO"):