[IE][VPU]: Added Mish layer (#1158)

* Add Mish stage in GraphTransformer
* Add Mish per-layer tests

inference-engine/src/vpu/graph_transformer/include/vpu/frontend/frontend.hpp

@@ -154,6 +154,7 @@ public:
     void parseOutShapeOfReshape(const Model& model, const ie::CNNLayerPtr& layer, const DataVector& inputs, const DataVector& outputs) const;
     void parseBroadcast(const Model& model, const ie::CNNLayerPtr& layer, const DataVector& inputs, const DataVector& outputs) const;
     void parseStaticShapeNMS(const Model& model, const ie::CNNLayerPtr& layer, const DataVector& inputs, const DataVector& outputs) const;
+    void parseMish(const Model& model, const ie::CNNLayerPtr& layer, const DataVector& inputs, const DataVector& outputs) const;
     void parseGelu(const Model& model, const ie::CNNLayerPtr& layer, const DataVector& inputs, const DataVector& outputs) const;
 
     //

inference-engine/src/vpu/graph_transformer/include/vpu/model/stage.hpp

@@ -167,6 +167,7 @@ VPU_DECLARE_ENUM(StageType,
     Concat = 128,
     Broadcast = 129,
     StaticShapeNMS = 130,
+    Mish = 131,
     Gelu = 132,
     StridedSlice = 133,
 )

inference-engine/src/vpu/graph_transformer/src/frontend/frontend.cpp

@@ -118,6 +118,7 @@ FrontEnd::FrontEnd(StageBuilder::Ptr stageBuilder)
         {"StaticShapeBroadcast",                               LAYER_PARSER(parseBroadcast)},
         {"StaticShapeNonMaxSuppression",                       LAYER_PARSER(parseStaticShapeNMS)},
         {"StaticShapeReshape",                                 LAYER_PARSER(parseReshape)},
+        {"Mish",                                               LAYER_PARSER(parseMish)},
         {"Gelu",                                               LAYER_PARSER(parseGelu)},
     }} {}
 

inference-engine/src/vpu/graph_transformer/src/stages/mish.cpp

@@ -0,0 +1,38 @@
+// Copyright (C) 2020 Intel Corporation
+// SPDX-License-Identifier: Apache-2.0
+//
+
+#include <vpu/frontend/frontend.hpp>
+#include <vpu/stages/post_op_stage.hpp>
+
+namespace vpu {
+
+namespace {
+
+class MishStage final : public PostOpStage {
+public:
+    using PostOpStage::PostOpStage;
+
+private:
+    StagePtr cloneImpl() const override {
+        return std::make_shared<MishStage>(*this);
+    }
+
+    void serializeParamsImpl(BlobSerializer&) const override {
+    }
+};
+
+}  // namespace
+
+void FrontEnd::parseMish(const Model& model, const ie::CNNLayerPtr& layer, const DataVector& inputs, const DataVector& outputs) const {
+    VPU_THROW_UNLESS(inputs.size() == 1,
+                     "Mish stage with name %s must have only 1 input, "
+                     "actually provided %d", layer->name, inputs.size());
+    VPU_THROW_UNLESS(outputs.size() == 1,
+                     "Mish stage with name %s must have only 1 output, "
+                     "actually provided %d", layer->name, outputs.size());
+
+    model->addNewStage<MishStage>(layer->name, StageType::Mish, layer, inputs, outputs);
+}
+
+}  // namespace vpu

inference-engine/tests/functional/plugin/myriad/shared_tests_instances/single_layer_tests/activation.cpp

@@ -21,7 +21,8 @@ const std::vector<ActivationTypes> activationTypes = {
         Relu,
         Exp,
         Log,
-        Gelu
+        Gelu,
+        Mish
 };
 
 std::map<std::vector<size_t>, std::vector<std::vector<size_t>>> basic = {