Merge branch 'master' into tfl/send_recv_op

src/ngraph/pass/fused_op_decomposition.cpp

@@ -13,36 +13,51 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 //*****************************************************************************
-
 #include "ngraph/pass/fused_op_decomposition.hpp"
-
 #include "ngraph/graph_util.hpp"
 #include "ngraph/op/get_output_element.hpp"
-#include "ngraph/op/util/fused_op.hpp"
 
 using namespace std;
 using namespace ngraph;
 
-bool ngraph::pass::FusedOpDecomposition::run_on_node(std::shared_ptr<ngraph::Node> node)
+pass::FusedOpDecomposition::FusedOpDecomposition(op_query_t callback)
+    : m_has_direct_support{callback}
+{
+}
+
+bool pass::FusedOpDecomposition::run_on_node(shared_ptr<Node> node)
 {
     bool modified = false;
 
-    if (auto fused_op = std::dynamic_pointer_cast<ngraph::op::util::FusedOp>(node))
+    if (auto fused_op = dynamic_pointer_cast<op::util::FusedOp>(node))
     {
-        if (m_callback && m_callback(*node))
+        if (m_has_direct_support && m_has_direct_support(*node))
         {
             // Op supported by backend. Do not decompose
             return modified;
         }
+
         auto subgraph_outputs = fused_op->decompose_op();
+        // Run recursively untill no more fused ops
+        auto subgraph = extract_subgraph(subgraph_outputs, fused_op->get_arguments());
+        for (auto subgraph_node : subgraph)
+        {
+            if (auto nested_fused_op = dynamic_pointer_cast<op::util::FusedOp>(subgraph_node))
+            {
+                if (!(m_has_direct_support && m_has_direct_support(*nested_fused_op)))
+                {
+                    run_on_node(nested_fused_op);
+                }
+            }
+        }
+
         size_t i = 0;
         for (auto output_node : subgraph_outputs)
         {
             for (size_t j = 0; j < output_node->get_outputs().size(); j++, i++)
             {
                 // TODO: Provenance
-                std::set<ngraph::descriptor::Input*> fop_users{
-                    begin(fused_op->get_outputs().at(i).get_inputs()),
+                set<descriptor::Input*> fop_users{begin(fused_op->get_outputs().at(i).get_inputs()),
                                                   end(fused_op->get_outputs().at(i).get_inputs())};
                 for (auto fop_user : fop_users)
                 {
@@ -52,7 +67,7 @@ bool ngraph::pass::FusedOpDecomposition::run_on_node(std::shared_ptr<ngraph::Nod
                         if (goe->get_n() == i && !goe->get_output_inputs(0).empty())
                         {
                             // Replace GOE users
-                            std::set<ngraph::descriptor::Input*> goe_users{
+                            set<descriptor::Input*> goe_users{
                                 begin(goe->get_outputs().at(0).get_inputs()),
                                 end(goe->get_outputs().at(0).get_inputs())};
                             for (auto goe_user : goe_users)
@@ -80,8 +95,3 @@ bool ngraph::pass::FusedOpDecomposition::run_on_node(std::shared_ptr<ngraph::Nod
 
     return modified;
 }
-
-pass::FusedOpDecomposition::FusedOpDecomposition(op_query_t callback)
-    : m_callback{callback}
-{
-}

src/ngraph/pass/fused_op_decomposition.hpp

@@ -16,6 +16,9 @@
 
 #pragma once
 
+#include <memory>
+
+#include "ngraph/op/util/fused_op.hpp"
 #include "ngraph/pass/pass.hpp"
 
 namespace ngraph
@@ -25,13 +28,24 @@ namespace ngraph
         class FusedOpDecomposition : public NodePass
         {
         public:
+            /// \brief  Function signature type for callback used to check whether provided node
+            ///         is supported by backend.
             using op_query_t = std::function<bool(const Node& node)>;
 
+            ///
+            /// \brief      Constructor for the Fused operation decomposition pass.
+            ///
+            /// \param[in]  callback  The function object used to determine whether current backend
+            ///                       provide direct support for passed node. Should have signature:
+            ///                       bool fn(const Node&)
+            ///
             FusedOpDecomposition(op_query_t callback = nullptr);
             bool run_on_node(std::shared_ptr<ngraph::Node> node) override;
 
         private:
-            op_query_t m_callback = nullptr;
+            /// \brief A function returning whether provided Node is supported by current backend.
+            ///        The returned bool value is used to control whether decompose operator or not.
+            op_query_t m_has_direct_support = nullptr;
         };
     }
 }

src/ngraph/runtime/cpu/cpu_external_function.cpp

@@ -1180,7 +1180,6 @@ void runtime::cpu::CPU_ExternalFunction::register_common_passes(
     REGISTER_KNOBBED_PASS(RecurrentReshapeElimination, false, ngraph::pass);
     REGISTER_KNOBBED_PASS_WITH_ARGS(
         CoreFusion, true, ngraph::pass, ngraph::pass::FusionType::ALL_FUSIONS);
-    REGISTER_KNOBBED_PASS_WITH_ARGS(FusedOpDecomposition, true, ngraph::pass, is_supported);
     REGISTER_KNOBBED_PASS(CPUFusion, true, runtime::cpu::pass);
     REGISTER_KNOBBED_PASS(CPUQuantFusion, true, runtime::cpu::pass);
     REGISTER_KNOBBED_PASS(CPUHorizontalFusion, true, runtime::cpu::pass);

src/ngraph/serializer.cpp

@@ -193,10 +193,15 @@ static OP_TYPEID get_typeid(const string& s)
     return rc;
 }
 
+bool has_key(json j, const std::string& key)
+{
+    return j.count(key) != 0;
+}
+
 template <typename T>
-T get_or_default(nlohmann::json& j, const std::string& key, const T& default_value)
+T get_or_default(json j, const std::string& key, const T& default_value)
 {
-    return j.count(key) != 0 ? j.at(key).get<T>() : default_value;
+    return has_key(j, key) ? j.at(key).get<T>() : default_value;
 }
 
 class JSONSerializer
@@ -215,8 +220,11 @@ public:
 
     json serialize_function(const Function& function);
     json serialize_output(const Output<Node>& output);
+    json serialize_parameter_vector(const ParameterVector& parameters);
+    json serialize_output_vector(const OutputVector& output_vector);
     json serialize_node_reference(const Node& node);
     json serialize_node(const Node& node);
+    json serialize_axis_set(const AxisSet& axis_set);
 
 protected:
     size_t m_indent{0};
@@ -235,10 +243,13 @@ public:
         m_const_data_callback = const_data_callback;
     }
 
-    shared_ptr<Function> deserialize_function(json& j);
-    Output<Node> deserialize_output(json& j);
-    shared_ptr<Node> deserialize_node_reference(json& j);
-    shared_ptr<Node> deserialize_node(json& j);
+    shared_ptr<Function> deserialize_function(json j);
+    Output<Node> deserialize_output(json j);
+    OutputVector deserialize_output_vector(json j);
+    ParameterVector deserialize_parameter_vector(json j);
+    shared_ptr<Node> deserialize_node_reference(json j);
+    shared_ptr<Node> deserialize_node(json j);
+    AxisSet deserialize_axis_set(json j);
 
 protected:
     unordered_map<string, shared_ptr<Node>> m_node_map;
@@ -261,7 +272,7 @@ static json write_dimension(Dimension d)
     }
 }
 
-static Dimension read_dimension(const json& j)
+static Dimension read_dimension(json j)
 {
     if (j.is_null())
     {
@@ -290,7 +301,7 @@ static json write_partial_shape(const PartialShape& s)
     }
 }
 
-static PartialShape read_partial_shape(const json& j)
+static PartialShape read_partial_shape(json j)
 {
     if (j.is_null())
     {
@@ -315,19 +326,32 @@ static json write_auto_broadcast(const op::AutoBroadcastSpec& autob)
     return j;
 }
 
-static op::AutoBroadcastSpec read_auto_broadcast(const json& j)
+static op::AutoBroadcastSpec read_auto_broadcast(json js_node, const std::string& attr)
 {
-    if (!j.is_object())
+    if (has_key(js_node, attr))
     {
-        return op::AutoBroadcastSpec();
+        json j = js_node[attr];
+        return op::AutoBroadcastSpec(static_cast<op::AutoBroadcastType>(j.at("type")),
+                                     j.at("axis").get<size_t>());
     }
     else
     {
-        return op::AutoBroadcastSpec(static_cast<op::AutoBroadcastType>(j.at("type")),
-                                     j.at("axis").get<size_t>());
+        return op::AutoBroadcastSpec();
     }
 }
 
+static op::PadType read_pad_type(json node_js)
+{
+    return has_key(node_js, "pad_type") ? static_cast<op::PadType>(node_js.at("pad_type"))
+                                        : op::PadType::EXPLICIT;
+}
+
+static op::PadMode read_pad_mode(json node_js)
+{
+    return has_key(node_js, "pad_mode") ? static_cast<op::PadMode>(node_js.at("pad_mode"))
+                                        : op::PadMode::CONSTANT;
+}
+
 static json write_element_type(const ngraph::element::Type& n)
 {
     json j;
@@ -335,7 +359,7 @@ static json write_element_type(const ngraph::element::Type& n)
     return j;
 }
 
-static element::Type read_element_type(const json& j)
+static element::Type read_element_type(json j)
 {
     size_t bitwidth = 0;
     bool is_real = false;
@@ -495,21 +519,24 @@ shared_ptr<ngraph::Function> ngraph::deserialize(const string& s)
             rc = deserializer.deserialize_function(func);
         }
     }
-
     return rc;
 }
 
+json JSONSerializer::serialize_parameter_vector(const ParameterVector& parameters)
+{
+    json json_parameters = json::array();
+    for (auto param : parameters)
+    {
+        json_parameters.push_back(serialize_node_reference(*param));
+    }
+    return json_parameters;
+}
+
 json JSONSerializer::serialize_function(const Function& f)
 {
     json function;
     function["name"] = f.get_name();
-
-    vector<string> parameter_list;
-    for (auto param : f.get_parameters())
-    {
-        parameter_list.push_back(serialize_node_reference(*param));
-    }
-    function["parameters"] = parameter_list;
+    function["parameters"] = serialize_parameter_vector(f.get_parameters());
 
     // TODO Functions can return multiple results
     for (size_t i = 0; i < f.get_output_size(); ++i)
@@ -521,7 +548,7 @@ json JSONSerializer::serialize_function(const Function& f)
 }
 
 template <typename T>
-T get_value(nlohmann::json js, const string& key)
+T get_value(json js, const string& key)
 {
     T rc;
     auto it = js.find(key);
@@ -532,13 +559,13 @@ T get_value(nlohmann::json js, const string& key)
     return rc;
 }
 
-shared_ptr<Node> JSONDeserializer::deserialize_node_reference(json& j)
+shared_ptr<Node> JSONDeserializer::deserialize_node_reference(json j)
 {
     const string& name = j;
     return m_node_map.at(name);
 }
 
-Output<Node> JSONDeserializer::deserialize_output(json& j)
+Output<Node> JSONDeserializer::deserialize_output(json j)
 {
     size_t index;
     json json_node_reference;
@@ -559,10 +586,48 @@ Output<Node> JSONDeserializer::deserialize_output(json& j)
     return Output<Node>(deserialize_node_reference(json_node_reference), index);
 }
 
-shared_ptr<Function> JSONDeserializer::deserialize_function(json& func_js)
+OutputVector JSONDeserializer::deserialize_output_vector(json j)
+{
+    OutputVector result;
+    if (j.is_array())
+    {
+        for (json jelt : j)
+        {
+            result.push_back(deserialize_output(jelt));
+        }
+    }
+    return result;
+}
+
+json JSONSerializer::serialize_axis_set(const AxisSet& axis_set)
+{
+    return static_cast<set<size_t>>(axis_set);
+}
+
+AxisSet JSONDeserializer::deserialize_axis_set(json j)
+{
+    AxisSet result;
+    if (j.is_array())
+    {
+        result = j.get<set<size_t>>();
+    }
+    return result;
+}
+
+ParameterVector JSONDeserializer::deserialize_parameter_vector(json json_parameters)
+{
+    std::vector<std::shared_ptr<op::Parameter>> params;
+    for (auto& param_ref : json_parameters)
+    {
+        params.push_back(
+            dynamic_pointer_cast<op::Parameter>(deserialize_node_reference(param_ref)));
+    }
+    return params;
+}
+
+shared_ptr<Function> JSONDeserializer::deserialize_function(json func_js)
 {
     string func_name = func_js.at("name").get<string>();
-    vector<json> func_parameters = func_js.at("parameters");
     vector<json> func_result = func_js.at("result");
     for (json node_js : func_js.at("ops"))
     {
@@ -594,12 +659,7 @@ shared_ptr<Function> JSONDeserializer::deserialize_function(json& func_js)
             "Graph serialization is inconsistent. Some op::Results appear to be missing");
     }
 
-    std::vector<std::shared_ptr<op::Parameter>> params;
-    for (auto& param_ref : func_parameters)
-    {
-        params.push_back(
-            dynamic_pointer_cast<op::Parameter>(deserialize_node_reference(param_ref)));
-    }
+    ParameterVector params = deserialize_parameter_vector(func_js.at("parameters"));
 
     shared_ptr<Function> rc{make_shared<Function>(result, params, func_name)};
     m_function_map[func_name] = rc;
@@ -632,7 +692,12 @@ struct OutputHelper
 // when all op constructors use the new style arguments.
 struct OutputVectorHelper
 {
-    const OutputHelper& operator[](size_t i) const { return m_vector[i]; }
+    OutputVectorHelper(const OutputVector& output_vector)
+        : m_vector(output_vector)
+    {
+    }
+    OutputVectorHelper() = default;
+    OutputHelper operator[](size_t i) const { return OutputHelper(m_vector[i]); }
     void push_back(const Output<Node>& output) { m_vector.push_back(output); }
     size_t size() const { return m_vector.size(); }
     operator vector<shared_ptr<Node>>() const
@@ -640,14 +705,15 @@ struct OutputVectorHelper
         vector<shared_ptr<Node>> result;
         for (auto& o : m_vector)
         {
-            result.push_back(o);
+            result.push_back(OutputHelper(o));
         }
         return result;
     }
-    vector<OutputHelper> m_vector;
+    operator const OutputVector&() const { return m_vector; }
+    OutputVector m_vector;
 };
 
-shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
+shared_ptr<Node> JSONDeserializer::deserialize_node(json node_js)
 {
     shared_ptr<Node> node;
     try
@@ -655,14 +721,9 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         string node_name = node_js.at("name").get<string>();
         string node_op = node_js.at("op").get<string>();
         string friendly_name = get_value<string>(node_js, "friendly_name");
-        vector<json> node_inputs = get_value<vector<json>>(node_js, "inputs");
         vector<json> control_deps_inputs = get_value<vector<json>>(node_js, "control_deps");
         vector<string> node_outputs = get_value<vector<string>>(node_js, "outputs");
-        OutputVectorHelper args;
-        for (auto& node_input : node_inputs)
-        {
-            args.push_back(deserialize_output(node_input));
-        }
+        OutputVectorHelper args(deserialize_output_vector(node_js["inputs"]));
 #if !(defined(__GNUC__) && __GNUC__ == 4 && __GNUC_MINOR__ == 8)
 #pragma GCC diagnostic push
 #pragma GCC diagnostic error "-Wswitch"
@@ -683,12 +744,12 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         }
         case OP_TYPEID::Add:
         {
-            node = make_shared<op::Add>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+            node = make_shared<op::Add>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::All:
         {
-            auto reduction_axes = node_js.at("reduction_axes").get<set<size_t>>();
+            auto reduction_axes = deserialize_axis_set(node_js.at("reduction_axes"));
             node = make_shared<op::All>(args[0], reduction_axes);
             break;
         }
@@ -699,12 +760,12 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         }
         case OP_TYPEID::And:
         {
-            node = make_shared<op::And>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+            node = make_shared<op::And>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::Any:
         {
-            auto reduction_axes = node_js.at("reduction_axes").get<set<size_t>>();
+            auto reduction_axes = deserialize_axis_set(node_js.at("reduction_axes"));
             node = make_shared<op::Any>(args[0], reduction_axes);
             break;
         }
@@ -741,12 +802,8 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
             auto padding_above = node_js.at("padding_above").get<vector<size_t>>();
             auto include_padding_in_avg_computation =
                 node_js.at("include_padding_in_avg_computation").get<bool>();
-            op::PadType pad_type = node_js["pad_type"].empty()
-                                       ? op::PadType::EXPLICIT
-                                       : static_cast<op::PadType>(node_js.at("pad_type"));
-            bool ceil_mode =
-                node_js["ceil_mode"].empty() ? false : node_js.at("ceil_mode").get<bool>();
-            ;
+            op::PadType pad_type = read_pad_type(node_js);
+            bool ceil_mode = get_or_default<bool>(node_js, "ceil_mode", false);
             node = make_shared<op::AvgPool>(args[0],
                                             window_shape,
                                             window_movement_strides,
@@ -808,7 +865,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         case OP_TYPEID::Broadcast:
         {
             auto shape = node_js.at("shape").get<vector<size_t>>();
-            auto axes = node_js.at("axes").get<set<size_t>>();
+            auto axes = deserialize_axis_set(node_js.at("axes"));
             node = make_shared<op::Broadcast>(args[0], shape, axes);
             break;
         }
@@ -819,7 +876,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         }
         case OP_TYPEID::BroadcastLike:
         {
-            auto initial_axes = node_js.at("initial_axes").get<set<size_t>>();
+            auto initial_axes = deserialize_axis_set(node_js.at("initial_axes"));
             node = make_shared<op::BroadcastLike>(args[0], args[1], initial_axes);
             break;
         }
@@ -838,13 +895,13 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         case OP_TYPEID::Concat:
         {
             auto axis = node_js.at("axis").get<size_t>();
-            node = make_shared<op::Concat>(args, axis);
+            node = make_shared<op::Concat>(static_cast<OutputVector>(args), axis);
             break;
         }
         case OP_TYPEID::Constant:
         {
             auto type_node_js =
-                node_js.count("element_type") == 0 ? node_js.at("value_type") : node_js;
+                has_key(node_js, "element_type") ? node_js : node_js.at("value_type");
             auto element_type = read_element_type(type_node_js.at("element_type"));
             auto shape = type_node_js.at("shape");
             auto value = node_js.at("value").get<vector<string>>();
@@ -868,17 +925,19 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
 
             // For backwards compatibility, we accept "image_dilation_strides" in place of
             // "data_dilation_strides", and we also allow it to be omitted altogether.
-            auto data_dilation_strides_maybe = node_js["data_dilation_strides"];
-            if (data_dilation_strides_maybe.empty())
+            json data_dilation_strides;
+            if (has_key(node_js, "data_dilation_strides"))
+            {
+                data_dilation_strides = node_js["data_dilation_strides"];
+            }
+            else if (has_key(node_js, "image_dilation_strides"))
             {
-                data_dilation_strides_maybe = node_js["image_dilation_strides"];
+                data_dilation_strides = node_js["image_dilation_strides"];
             }
 
-            op::PadType pad_type = node_js["pad_type"].empty()
-                                       ? op::PadType::EXPLICIT
-                                       : static_cast<op::PadType>(node_js.at("pad_type"));
+            op::PadType pad_type = read_pad_type(node_js);
 
-            if (data_dilation_strides_maybe.empty())
+            if (data_dilation_strides.empty())
             {
                 node = make_shared<op::Convolution>(args[0],
                                                     args[1],
@@ -889,14 +948,14 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
             }
             else
             {
-                node = make_shared<op::Convolution>(
-                    args[0],
+                node =
+                    make_shared<op::Convolution>(args[0],
                                                  args[1],
                                                  window_movement_strides,
                                                  window_dilation_strides,
                                                  padding_below,
                                                  padding_above,
-                    data_dilation_strides_maybe.get<std::vector<size_t>>(),
+                                                 data_dilation_strides.get<std::vector<size_t>>(),
                                                  pad_type);
             }
             break;
@@ -1033,33 +1092,28 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         case OP_TYPEID::Dequantize:
         {
             auto type = read_element_type(node_js.at("type"));
-            auto axes = node_js.at("axes").get<set<size_t>>();
+            auto axes = deserialize_axis_set(node_js.at("axes"));
             node = make_shared<op::Dequantize>(args[0], args[1], args[2], type, axes);
             break;
         }
         case OP_TYPEID::Divide:
         {
-            bool pythondiv = true;
-            if (node_js["pythondiv"].is_object())
-            {
-                pythondiv = node_js.at("pythondiv").get<bool>();
-            }
+            bool pythondiv = get_or_default(node_js, "pythondiv", true);
             node = make_shared<op::Divide>(
-                args[0], args[1], pythondiv, read_auto_broadcast(node_js["autob"]));
+                args[0], args[1], pythondiv, read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::Dot:
         {
             // For backwards compatibility, reduction_axes_count is optional.
-            auto obj = node_js["reduction_axes_count"];
-            if (obj.empty())
+            if (has_key(node_js, "reduction_axes_count"))
             {
-                node = make_shared<op::Dot>(args[0], args[1]);
+                size_t reduction_axes_count = node_js["reduction_axes_count"].get<size_t>();
+                node = make_shared<op::Dot>(args[0], args[1], reduction_axes_count);
             }
             else
             {
-                size_t reduction_axes_count = obj.get<size_t>();
-                node = make_shared<op::Dot>(args[0], args[1], reduction_axes_count);
+                node = make_shared<op::Dot>(args[0], args[1]);
             }
             break;
         }
@@ -1095,7 +1149,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         }
         case OP_TYPEID::Equal:
         {
-            node = make_shared<op::Equal>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+            node = make_shared<op::Equal>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::Erf:
@@ -1160,13 +1214,13 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         case OP_TYPEID::Greater:
         {
             node =
-                make_shared<op::Greater>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+                make_shared<op::Greater>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::GreaterEq:
         {
             node =
-                make_shared<op::GreaterEq>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+                make_shared<op::GreaterEq>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::GRN:
@@ -1193,10 +1247,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
             auto data_dilation_strides = node_js.at("data_dilation_strides").get<vector<size_t>>();
             auto groups = node_js.at("groups").get<size_t>();
 
-            op::PadType pad_type = node_js["pad_type"].empty()
-                                       ? op::PadType::EXPLICIT
-                                       : static_cast<op::PadType>(node_js.at("pad_type"));
-
+            op::PadType pad_type = read_pad_type(node_js);
             node = make_shared<op::GroupConvolution>(args[0],
                                                      args[1],
                                                      window_movement_strides,
@@ -1216,9 +1267,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
             auto padding_end = node_js.at("padding_end").get<vector<ptrdiff_t>>();
             auto output_padding = node_js.at("output_padding").get<vector<ptrdiff_t>>();
             auto groups = node_js.at("groups").get<size_t>();
-            op::PadType pad_type = node_js["pad_type"].empty()
-                                       ? op::PadType::EXPLICIT
-                                       : static_cast<op::PadType>(node_js.at("pad_type"));
+            op::PadType pad_type = read_pad_type(node_js);
             auto output_shape = node_js.at("output_shape").get<vector<size_t>>();
 
             node = make_shared<op::GroupConvolutionTranspose>(args[0],
@@ -1240,12 +1289,12 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         }
         case OP_TYPEID::Less:
         {
-            node = make_shared<op::Less>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+            node = make_shared<op::Less>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::LessEq:
         {
-            node = make_shared<op::LessEq>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+            node = make_shared<op::LessEq>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::Log:
@@ -1287,7 +1336,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         }
         case OP_TYPEID::Max:
         {
-            auto reduction_axes = node_js.at("reduction_axes").get<set<size_t>>();
+            auto reduction_axes = deserialize_axis_set(node_js.at("reduction_axes"));
             node = make_shared<op::Max>(args[0], reduction_axes);
             break;
         }
@@ -1298,11 +1347,9 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
                 node_js.at("window_movement_strides").get<vector<size_t>>();
             // For backwards compatibility, both (but not just one) of the padding_ fields may be
             // omitted.
-            auto padding_below_maybe = node_js["padding_below"];
-            auto padding_above_maybe = node_js["padding_above"];
-            op::PadType pad_type = node_js["pad_type"].empty()
-                                       ? op::PadType::EXPLICIT
-                                       : static_cast<op::PadType>(node_js.at("pad_type"));
+            auto padding_below_maybe = get_or_default(node_js, "padding_below", json{});
+            auto padding_above_maybe = get_or_default(node_js, "padding_above", json{});
+            op::PadType pad_type = read_pad_type(node_js);
             if (padding_below_maybe.empty() && !padding_above_maybe.empty())
             {
                 throw runtime_error(
@@ -1361,31 +1408,31 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         case OP_TYPEID::Maximum:
         {
             node =
-                make_shared<op::Maximum>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+                make_shared<op::Maximum>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::Min:
         {
-            auto reduction_axes = node_js.at("reduction_axes").get<set<size_t>>();
+            auto reduction_axes = deserialize_axis_set(node_js.at("reduction_axes"));
             node = make_shared<op::Min>(args[0], reduction_axes);
             break;
         }
         case OP_TYPEID::Minimum:
         {
             node =
-                make_shared<op::Minimum>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+                make_shared<op::Minimum>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::Multiply:
         {
             node =
-                make_shared<op::Multiply>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+                make_shared<op::Multiply>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::MVN:
         {
             auto normalize_variance = node_js.at("normalize_variance").get<bool>();
-            auto reduction_axes = node_js.at("reduction_axes").get<set<size_t>>();
+            auto reduction_axes = deserialize_axis_set(node_js.at("reduction_axes"));
             auto eps = node_js.at("eps").get<double>();
             node = make_shared<op::MVN>(args[0], normalize_variance, normalize_variance, eps);
             break;
@@ -1407,7 +1454,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         case OP_TYPEID::NotEqual:
         {
             node =
-                make_shared<op::NotEqual>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+                make_shared<op::NotEqual>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::Not:
@@ -1424,7 +1471,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         }
         case OP_TYPEID::Or:
         {
-            node = make_shared<op::Or>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+            node = make_shared<op::Or>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::Pad:
@@ -1441,9 +1488,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
                                      [](size_t s) { return s == 0; }),
                          "Legacy padding_interior field must be zero everywhere.");
 
-            auto pad_mode = node_js.count("pad_mode") == 0
-                                ? op::PadMode::CONSTANT
-                                : static_cast<op::PadMode>(node_js.at("pad_mode"));
+            auto pad_mode = read_pad_mode(node_js);
 
             node = make_shared<op::Pad>(args[0], args[1], padding_below, padding_above, pad_mode);
             break;
@@ -1451,7 +1496,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         case OP_TYPEID::Parameter:
         {
             auto type_node_js =
-                node_js.count("element_type") == 0 ? node_js.at("value_type") : node_js;
+                has_key(node_js, "element_type") ? node_js : node_js.at("value_type");
             auto element_type = read_element_type(type_node_js.at("element_type"));
             auto shape = type_node_js.at("shape");
             auto cacheable = get_or_default<bool>(node_js, "cacheable", false);
@@ -1476,7 +1521,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         }
         case OP_TYPEID::Power:
         {
-            node = make_shared<op::Power>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+            node = make_shared<op::Power>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::PRelu:
@@ -1486,14 +1531,14 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         }
         case OP_TYPEID::Product:
         {
-            auto reduction_axes = node_js.at("reduction_axes").get<set<size_t>>();
+            auto reduction_axes = deserialize_axis_set(node_js.at("reduction_axes"));
             node = make_shared<op::Product>(args[0], reduction_axes);
             break;
         }
         case OP_TYPEID::Quantize:
         {
             auto type = read_element_type(node_js.at("type"));
-            auto axes = node_js.at("axes").get<set<size_t>>();
+            auto axes = deserialize_axis_set(node_js.at("axes"));
             auto round_mode = node_js.at("round_mode").get<op::Quantize::RoundMode>();
             node = make_shared<op::Quantize>(args[0], args[1], args[2], type, axes, round_mode);
             break;
@@ -1552,8 +1597,8 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
                 node_js.at("window_movement_strides").get<vector<size_t>>();
             // For backwards compatibility, both (but not just one) of the padding_ fields may be
             // omitted.
-            auto padding_below_maybe = node_js["padding_below"];
-            auto padding_above_maybe = node_js["padding_above"];
+            auto padding_below_maybe = get_or_default(node_js, "padding_below", json{});
+            auto padding_above_maybe = get_or_default(node_js, "padding_above", json{});
             auto padding_below = padding_below_maybe.get<vector<size_t>>();
             auto padding_above = padding_above_maybe.get<vector<size_t>>();
             node = make_shared<op::QuantizedMaxPool>(
@@ -1607,7 +1652,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         }
         case OP_TYPEID::Reverse:
         {
-            auto reversed_axes = node_js.at("reversed_axes").get<set<size_t>>();
+            auto reversed_axes = deserialize_axis_set(node_js.at("reversed_axes"));
             node = make_shared<op::Reverse>(args[0], reversed_axes);
             break;
         }
@@ -1697,7 +1742,7 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         }
         case OP_TYPEID::Softmax:
         {
-            auto softmax_axes = node_js.at("softmax_axes").get<set<size_t>>();
+            auto softmax_axes = deserialize_axis_set(node_js.at("softmax_axes"));
             node = make_shared<op::Softmax>(args[0], softmax_axes);
             break;
         }
@@ -1732,12 +1777,12 @@ shared_ptr<Node> JSONDeserializer::deserialize_node(json& node_js)
         case OP_TYPEID::Subtract:
         {
             node =
-                make_shared<op::Subtract>(args[0], args[1], read_auto_broadcast(node_js["autob"]));
+                make_shared<op::Subtract>(args[0], args[1], read_auto_broadcast(node_js, "autob"));
             break;
         }
         case OP_TYPEID::Sum:
         {
-            auto reduction_axes = node_js.at("reduction_axes").get<set<size_t>>();
+            auto reduction_axes = deserialize_axis_set(node_js.at("reduction_axes"));
             node = make_shared<op::Sum>(args[0], reduction_axes);
             break;
         }
@@ -1873,6 +1918,16 @@ json JSONSerializer::serialize_output(const Output<Node>& output)
     return result;
 }
 
+json JSONSerializer::serialize_output_vector(const OutputVector& output_vector)
+{
+    json result;
+    for (const Output<Node>& output : output_vector)
+    {
+        result.push_back(serialize_output(output));
+    }
+    return result;
+}
+
 json JSONSerializer::serialize_node(const Node& n)
 {
     m_nodes_serialized.insert(&n);
@@ -1972,7 +2027,7 @@ json JSONSerializer::serialize_node(const Node& n)
     case OP_TYPEID::All:
     {
         auto tmp = dynamic_cast<const op::All*>(&n);
-        node["reduction_axes"] = tmp->get_reduction_axes();
+        node["reduction_axes"] = serialize_axis_set(tmp->get_reduction_axes());
         break;
     }
     case OP_TYPEID::AllReduce: { break;
@@ -1989,7 +2044,7 @@ json JSONSerializer::serialize_node(const Node& n)
     case OP_TYPEID::Any:
     {
         auto tmp = dynamic_cast<const op::Any*>(&n);
-        node["reduction_axes"] = tmp->get_reduction_axes();
+        node["reduction_axes"] = serialize_axis_set(tmp->get_reduction_axes());
         break;
     }
     case OP_TYPEID::Asin: { break;
@@ -2045,7 +2100,7 @@ json JSONSerializer::serialize_node(const Node& n)
     case OP_TYPEID::Broadcast:
     {
         auto tmp = dynamic_cast<const op::Broadcast*>(&n);
-        node["axes"] = tmp->get_broadcast_axes();
+        node["axes"] = serialize_axis_set(tmp->get_broadcast_axes());
         node["shape"] = tmp->get_broadcast_shape();
         break;
     }
@@ -2054,7 +2109,7 @@ json JSONSerializer::serialize_node(const Node& n)
     case OP_TYPEID::BroadcastLike:
     {
         auto tmp = dynamic_cast<const op::BroadcastLike*>(&n);
-        node["initial_axes"] = tmp->get_initial_broadcast_axes();
+        node["initial_axes"] = serialize_axis_set(tmp->get_initial_broadcast_axes());
         break;
     }
     case OP_TYPEID::Ceiling: { break;
@@ -2168,7 +2223,7 @@ json JSONSerializer::serialize_node(const Node& n)
     {
         auto tmp = dynamic_cast<const op::Dequantize*>(&n);
         node["type"] = write_element_type(tmp->get_element_type());
-        node["axes"] = tmp->get_axes();
+        node["axes"] = serialize_axis_set(tmp->get_axes());
         break;
     }
     case OP_TYPEID::DepthToSpace:
@@ -2361,7 +2416,7 @@ json JSONSerializer::serialize_node(const Node& n)
     case OP_TYPEID::Max:
     {
         auto tmp = dynamic_cast<const op::Max*>(&n);
-        node["reduction_axes"] = tmp->get_reduction_axes();
+        node["reduction_axes"] = serialize_axis_set(tmp->get_reduction_axes());
         break;
     }
     case OP_TYPEID::MaxPool:
@@ -2395,7 +2450,7 @@ json JSONSerializer::serialize_node(const Node& n)
     case OP_TYPEID::Min:
     {
         auto tmp = dynamic_cast<const op::Min*>(&n);
-        node["reduction_axes"] = tmp->get_reduction_axes();
+        node["reduction_axes"] = serialize_axis_set(tmp->get_reduction_axes());
         break;
     }
     case OP_TYPEID::Minimum:
@@ -2419,7 +2474,7 @@ json JSONSerializer::serialize_node(const Node& n)
     case OP_TYPEID::MVN:
     {
         auto tmp = dynamic_cast<const op::MVN*>(&n);
-        node["reduction_axes"] = tmp->get_reduction_axes();
+        node["reduction_axes"] = serialize_axis_set(tmp->get_reduction_axes());
         node["normalize_variance"] = tmp->get_normalize_variance();
         node["eps"] = tmp->get_eps();
         break;
@@ -2499,7 +2554,7 @@ json JSONSerializer::serialize_node(const Node& n)
     case OP_TYPEID::Product:
     {
         auto tmp = dynamic_cast<const op::Product*>(&n);
-        node["reduction_axes"] = tmp->get_reduction_axes();
+        node["reduction_axes"] = serialize_axis_set(tmp->get_reduction_axes());
         break;
     }
     case OP_TYPEID::Power:
@@ -2515,7 +2570,7 @@ json JSONSerializer::serialize_node(const Node& n)
     {
         auto tmp = dynamic_cast<const op::Quantize*>(&n);
         node["type"] = write_element_type(tmp->get_element_type());
-        node["axes"] = tmp->get_axes();
+        node["axes"] = serialize_axis_set(tmp->get_axes());
         node["round_mode"] = tmp->get_round_mode();
         break;
     }
@@ -2596,7 +2651,7 @@ json JSONSerializer::serialize_node(const Node& n)
     case OP_TYPEID::Reverse:
     {
         auto tmp = dynamic_cast<const op::Reverse*>(&n);
-        node["reversed_axes"] = tmp->get_reversed_axes();
+        node["reversed_axes"] = serialize_axis_set(tmp->get_reversed_axes());
         break;
     }
     case OP_TYPEID::ReverseSequence:
@@ -2689,13 +2744,13 @@ json JSONSerializer::serialize_node(const Node& n)
     case OP_TYPEID::Sum:
     {
         auto tmp = dynamic_cast<const op::Sum*>(&n);
-        node["reduction_axes"] = tmp->get_reduction_axes();
+        node["reduction_axes"] = serialize_axis_set(tmp->get_reduction_axes());
         break;
     }
     case OP_TYPEID::Softmax:
     {
         auto tmp = dynamic_cast<const op::Softmax*>(&n);
-        node["softmax_axes"] = tmp->get_axes();
+        node["softmax_axes"] = serialize_axis_set(tmp->get_axes());
         break;
     }
     case OP_TYPEID::Tan: { break;