fix ut failure , root cause: loo_rewirter bug

Author: pengwa

tf2onnx/rewriter/cond_rewriter.py

@@ -120,7 +120,7 @@ def _get_output_shape_dtype(self, cond_context):
                 )
             if true_dtype != false_dtype:
                 raise RuntimeError(
-                    "the shape of outputs {} and {} mismatch: {}, {}".format(
+                    "the dtype of outputs {} and {} mismatch: {}, {}".format(
                         true_output,
                         false_output,
                         true_dtype,

tf2onnx/rewriter/loop_rewriter.py

@@ -102,7 +102,6 @@ def rewrite(self, context):
             return REWRITER_RESULT.FAIL
 
     def _create_loop_node(self, context, loop_props):
-        # reuse original output connection id (e.g. Exit_XXX), so we don't need set shape.
         loop_outputs = []
         loop_output_shapes = []
         loop_output_dtypes = []
@@ -125,6 +124,7 @@ def _create_loop_node(self, context, loop_props):
         loop_node = self.g.make_node("Loop", [trip_cnt.output[0]] + [cond.output[0]] +
                                      loop_props.state_inputs_initial_values,  # ONNX Loop support state inputs only
                                      outputs=loop_outputs, op_name_scope="generic_loop",
+                                     shapes=loop_output_shapes, dtypes=loop_output_dtypes,
                                      skip_conversion=False)
 
         return loop_node