!7517 Choose the date type for idx in the infer implementation for Unique

Merge pull request !7517 from YuJianfeng/master

mindspore/core/abstract/prim_arrays.cc

@@ -167,7 +167,12 @@ AbstractBasePtr InferImplUnique(const AnalysisEnginePtr &, const PrimitivePtr &p
   ShapeVector max_shape = shape->shape();
   auto ids =
     std::make_shared<AbstractTensor>(input->element(), std::make_shared<Shape>(ids_shape, min_shape, max_shape));
-  auto ids_idx = std::make_shared<AbstractTensor>(std::make_shared<Int>(32), shape->shape());
+  // Currently we choose the same data type as input for the idx.
+  TypePtr ids_idx_type = kInt32;
+  if (input->element() != nullptr && input->element()->GetTypeTrack() != nullptr) {
+    ids_idx_type = input->element()->GetTypeTrack();
+  }
+  auto ids_idx = std::make_shared<AbstractTensor>(ids_idx_type, shape->shape());
   // outputs: ids, ids_idx
   AbstractBasePtrList elements = {ids, ids_idx};
   return std::make_shared<AbstractTuple>(elements);