Update ONNX importer to use v1 version of Softmax (#3894)

* Added downgrade pass for Softmax.

* Updated Softmax op to v1.

* Created vector with a right capacity.

* Include numeric header to enable std::iota function

* Removed unused numeric header from the old file

* Fix includes style

src/ngraph/frontend/onnx_import/op/softmax.cpp

@@ -14,9 +14,8 @@
 // limitations under the License.
 //*****************************************************************************
 
-#include <numeric>
+#include <memory>
 
-#include "exceptions.hpp"
 #include "ngraph/op/softmax.hpp"
 #include "softmax.hpp"
 #include "utils/common.hpp"
@@ -38,10 +37,7 @@ namespace ngraph
                     int axis = node.get_attribute_value<int64_t>("axis", 1);
                     std::size_t valid_axis = common::validate_axis(node, axis, data_shape.size());
 
-                    // create vector of capacity data_dimensions - axis_divider position
-                    std::vector<size_t> axes(data_shape.size() - valid_axis);
-                    std::iota(std::begin(axes), std::end(axes), valid_axis);
-                    return {std::make_shared<ngraph::op::Softmax>(data, axes)};
+                    return {std::make_shared<ngraph::op::v1::Softmax>(data, valid_axis)};
                 }
             } // namespace set_1
 

src/ngraph/frontend/onnx_import/op/softmax.hpp

@@ -16,9 +16,8 @@
 
 #pragma once
 
-#include <memory>
-
 #include "core/node.hpp"
+#include "ngraph/node.hpp"
 
 namespace ngraph
 {

src/ngraph/pass/opset0_downgrade.cpp

@@ -15,6 +15,7 @@
 //*****************************************************************************
 
 #include <cstdint>
+#include <numeric>
 
 #include "ngraph/graph_util.hpp"
 #include "ngraph/node.hpp"
@@ -48,6 +49,7 @@
 #include "ngraph/op/reshape.hpp"
 #include "ngraph/op/reverse.hpp"
 #include "ngraph/op/slice.hpp"
+#include "ngraph/op/softmax.hpp"
 #include "ngraph/op/strided_slice.hpp"
 #include "ngraph/op/sum.hpp"
 #include "ngraph/op/topk.hpp"
@@ -609,6 +611,20 @@ bool pass::Opset0Downgrade::run_on_node(shared_ptr<Node> node)
         replace_node(node, replacement_node);
         break;
     }
+    case OP_TYPEID::Softmax:
+    {
+        auto tmp = as_type_ptr<op::v1::Softmax>(node);
+        auto axis = tmp->get_axis();
+        auto data = node->input(0);
+        auto data_shape = data.get_shape();
+        std::vector<size_t> axes(data_shape.size() - axis);
+        std::iota(std::begin(axes), std::end(axes), axis);
+        auto replacement_node =
+            make_shared<op::v0::Softmax>(node->input(0).get_source_output(), axes);
+        replace_node(node, replacement_node);
+        modified = true;
+        break;
+    }
     case OP_TYPEID::Sum:
     {
         auto tmp = as_type_ptr<op::v1::ReduceSum>(node);