Add test onnx.Cast bf16 to f16

Author: AmosLewis

alt_e2eshark/onnx_tests/operators/cast.py

@@ -0,0 +1,25 @@
+# Copyright 2024 Advanced Micro Devices, Inc.
+#
+# Licensed under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+from onnx import TensorProto
+from onnx.helper import make_node, make_tensor_value_info, make_attribute
+
+from ..helper_classes import BuildAModel
+from e2e_testing.registry import register_test
+
+class CastModel(BuildAModel):
+    def construct_i_o_value_info(self):
+        self.input_vi = [
+            make_tensor_value_info("X", TensorProto.BFLOAT16, [1]),
+        ]
+        self.output_vi = [make_tensor_value_info("Y", TensorProto.FLOAT16, [1])]
+
+    def construct_nodes(self):
+        cast_node = make_node("Cast", ["X"], ["Y"], "castnode")
+        cast_node.attribute.append(make_attribute("to", 10))
+        self.node_list.append(cast_node)
+
+register_test(CastModel, "cast_test")
+