IVGCVSW-2915 Add Merge Layer and no-op factory method

Change-Id: I54549671e0d3b207904cf9796a843eb2b0a631f7
Signed-off-by: Nattapat Chaimanowong <nattapat.chaimanowong@arm.com>

5 files changed, 60 insertions, 2 deletions

diff --git a/src/armnnSerializer/ArmnnSchema.fbs b/src/armnnSerializer/ArmnnSchema.fbs
index 3aa644dbe5..8b275b6f17 100644
--- a/src/armnnSerializer/ArmnnSchema.fbs
+++ b/src/armnnSerializer/ArmnnSchema.fbs
@@ -118,7 +118,8 @@ enum LayerType : uint {
     DetectionPostProcess = 33,
     Lstm = 34,
     Quantize = 35,
-    Dequantize = 36
+    Dequantize = 36,
+    Merge = 37
 }
 
 // Base layer table to be used as part of other layers
@@ -524,6 +525,10 @@ table DequantizeLayer {
     base:LayerBase;
 }
 
+table MergeLayer {
+    base:LayerBase;
+}
+
 union Layer {
     ActivationLayer,
     AdditionLayer,
@@ -561,7 +566,8 @@ union Layer {
     DetectionPostProcessLayer,
     LstmLayer,
     QuantizeLayer,
-    DequantizeLayer
+    DequantizeLayer,
+    MergeLayer
 }
 
 table AnyLayer {
diff --git a/src/armnnSerializer/Serializer.cpp b/src/armnnSerializer/Serializer.cpp
index 7181f01e6b..fe30c3eee5 100644
--- a/src/armnnSerializer/Serializer.cpp
+++ b/src/armnnSerializer/Serializer.cpp
@@ -500,6 +500,14 @@ void SerializerVisitor::VisitMinimumLayer(const armnn::IConnectableLayer* layer,
     CreateAnyLayer(fbMinimumLayer.o, serializer::Layer::Layer_MinimumLayer);
 }
 
+void SerializerVisitor::VisitMergeLayer(const armnn::IConnectableLayer* layer, const char* name)
+{
+    auto fbMergeBaseLayer = CreateLayerBase(layer, serializer::LayerType::LayerType_Merge);
+    auto fbMergeLayer     = serializer::CreateMergeLayer(m_flatBufferBuilder, fbMergeBaseLayer);
+
+    CreateAnyLayer(fbMergeLayer.o, serializer::Layer::Layer_MergeLayer);
+}
+
 void SerializerVisitor::VisitMergerLayer(const armnn::IConnectableLayer* layer,
                                          const armnn::OriginsDescriptor& mergerDescriptor,
                                          const char* name)
diff --git a/src/armnnSerializer/Serializer.hpp b/src/armnnSerializer/Serializer.hpp
index 5c3e48a695..775df83966 100644
--- a/src/armnnSerializer/Serializer.hpp
+++ b/src/armnnSerializer/Serializer.hpp
@@ -129,6 +129,9 @@ public:
     void VisitMaximumLayer(const armnn::IConnectableLayer* layer,
                            const char* name = nullptr) override;
 
+    void VisitMergeLayer(const armnn::IConnectableLayer* layer,
+                         const char* name = nullptr) override;
+
     void VisitMergerLayer(const armnn::IConnectableLayer* layer,
                           const armnn::OriginsDescriptor& mergerDescriptor,
                           const char* name = nullptr) override;
diff --git a/src/armnnSerializer/SerializerSupport.md b/src/armnnSerializer/SerializerSupport.md
index a3c5852bd2..a8335e1e68 100644
--- a/src/armnnSerializer/SerializerSupport.md
+++ b/src/armnnSerializer/SerializerSupport.md
@@ -25,6 +25,7 @@ The Arm NN SDK Serializer currently supports the following layers:
 * Lstm
 * Maximum
 * Mean
+* Merge
 * Merger
 * Minimum
 * Multiplication
diff --git a/src/armnnSerializer/test/SerializerTests.cpp b/src/armnnSerializer/test/SerializerTests.cpp
index 0979076476..a1ef9eef59 100644
--- a/src/armnnSerializer/test/SerializerTests.cpp
+++ b/src/armnnSerializer/test/SerializerTests.cpp
@@ -1185,6 +1185,46 @@ BOOST_AUTO_TEST_CASE(SerializeMean)
     deserializedNetwork->Accept(verifier);
 }
 
+BOOST_AUTO_TEST_CASE(SerializeMerge)
+{
+    class MergeLayerVerifier : public LayerVerifierBase
+    {
+    public:
+        MergeLayerVerifier(const std::string& layerName,
+                           const std::vector<armnn::TensorInfo>& inputInfos,
+                           const std::vector<armnn::TensorInfo>& outputInfos)
+        : LayerVerifierBase(layerName, inputInfos, outputInfos) {}
+
+        void VisitMergeLayer(const armnn::IConnectableLayer* layer, const char* name) override
+        {
+            VerifyNameAndConnections(layer, name);
+        }
+    };
+
+    const std::string layerName("merge");
+    const armnn::TensorInfo info({ 1, 2, 2, 3 }, armnn::DataType::Float32);
+
+    armnn::INetworkPtr network = armnn::INetwork::Create();
+    armnn::IConnectableLayer* const inputLayer0 = network->AddInputLayer(0);
+    armnn::IConnectableLayer* const inputLayer1 = network->AddInputLayer(1);
+    armnn::IConnectableLayer* const mergeLayer = network->AddMergeLayer(layerName.c_str());
+    armnn::IConnectableLayer* const outputLayer = network->AddOutputLayer(0);
+
+    inputLayer0->GetOutputSlot(0).Connect(mergeLayer->GetInputSlot(0));
+    inputLayer1->GetOutputSlot(0).Connect(mergeLayer->GetInputSlot(1));
+    mergeLayer->GetOutputSlot(0).Connect(outputLayer->GetInputSlot(0));
+
+    inputLayer0->GetOutputSlot(0).SetTensorInfo(info);
+    inputLayer1->GetOutputSlot(0).SetTensorInfo(info);
+    mergeLayer->GetOutputSlot(0).SetTensorInfo(info);
+
+    armnn::INetworkPtr deserializedNetwork = DeserializeNetwork(SerializeNetwork(*network));
+    BOOST_CHECK(deserializedNetwork);
+
+    MergeLayerVerifier verifier(layerName, {info, info}, {info});
+    deserializedNetwork->Accept(verifier);
+}
+
 BOOST_AUTO_TEST_CASE(SerializeMerger)
 {
     class MergerLayerVerifier : public LayerVerifierBase