diff --git a/ethosu/vela/high_level_command_stream_generator.py b/ethosu/vela/high_level_command_stream_generator.py
index d02fd85..232a56c 100644
--- a/ethosu/vela/high_level_command_stream_generator.py
+++ b/ethosu/vela/high_level_command_stream_generator.py
@@ -216,7 +216,7 @@
         if len(passes) == 1:
             # no cascading, can just issue one big stripe
             # but only if we've done allocation and OFM does not overlap IFM
-            if ifm_tensor.address != -1 and ofm_tensor.address != -1:
+            if ifm_tensor.address is not None and ofm_tensor.address is not None:
                 if (
                     ifm_tensor.address + ifm_tensor.storage_size() <= ofm_tensor.address
                     or ofm_tensor.address + ofm_tensor.storage_size() <= ifm_tensor.address