Use --opset-version provided by iree-import-onnx. (#776)

This option was added in
iree-org/iree@d497571.

shortfin/tests/invocation/conftest.py

@@ -8,31 +8,21 @@
 import urllib.request
 
 
-def upgrade_onnx(original_path, converted_path):
-    import onnx
-
-    original_model = onnx.load_model(original_path)
-    converted_model = onnx.version_converter.convert_version(original_model, 17)
-    onnx.save(converted_model, converted_path)
-
-
 @pytest.fixture(scope="session")
 def mobilenet_onnx_path(tmp_path_factory):
     try:
         import onnx
     except ModuleNotFoundError:
         raise pytest.skip("onnx python package not available")
     parent_dir = tmp_path_factory.mktemp("mobilenet_onnx")
-    orig_onnx_path = parent_dir / "mobilenet_orig.onnx"
-    upgraded_onnx_path = parent_dir / "mobilenet.onnx"
-    if not upgraded_onnx_path.exists():
+    onnx_path = parent_dir / "mobilenet.onnx"
+    if not onnx_path.exists():
         print("Downloading mobilenet.onnx")
         urllib.request.urlretrieve(
             "https://github.com/onnx/models/raw/main/validated/vision/classification/mobilenet/model/mobilenetv2-12.onnx",
-            orig_onnx_path,
+            onnx_path,
         )
-        upgrade_onnx(orig_onnx_path, upgraded_onnx_path)
-    return upgraded_onnx_path
+    return onnx_path
 
 
 @pytest.fixture(scope="session")
@@ -47,7 +37,7 @@ def mobilenet_compiled_path(mobilenet_onnx_path, compile_flags):
     if not vmfb_path.exists():
         print("Compiling mobilenet")
         args = import_onnx.parse_arguments(
-            ["-o", str(mlir_path), str(mobilenet_onnx_path)]
+            ["-o", str(mlir_path), str(mobilenet_onnx_path), "--opset-version", "17"]
         )
         import_onnx.main(args)
         tools.compile_file(