[torchlib] Improve aten::fill (#1754)

I updated torch-onnx to handle empty `[]` inputs, so the isinstance
check is not needed.

onnxscript/function_libs/torch_lib/ops/core.py

@@ -3622,10 +3622,6 @@ def aten_full(
 
     if dtype != -1:
         fill_value = op.Cast(fill_value, to=dtype)
-    if isinstance(size, list) and size == []:
-        # TODO(justinchuby): Handle empty list better than using isinstance
-        # size can be empty, meaning a scalar
-        return fill_value
 
     size = op.Cast(size, to=INT64.dtype)
     return op.Expand(fill_value, size)

onnxscript/tools/benchmark/benchmark_helpers.py

@@ -287,7 +287,7 @@ def common_export(
     if exporter == "script":
         torch.onnx.export(
             model,
-            inputs,
+            inputs,  # type: ignore[arg-type]
             filename,
             do_constant_folding=False,
             input_names=[f"input{i}" for i in range(len(inputs))],

onnxscript/tools/transformers_models/__init__.py

@@ -41,6 +41,7 @@ def export_to_onnx(
             prog = torch.onnx.export(model, args, dynamo=True)  # pylint: disable=no-value-for-parameter
         else:
             prog = torch.onnx.dynamo_export(model, *args)
+    assert prog is not None
     model_proto = prog.model_proto
     if optimize:
         model_proto = onnxscript.optimizer.optimize(