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

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

2 files changed, 112 insertions, 0 deletions

diff --git a/src/armnn/layers/MergeLayer.cpp b/src/armnn/layers/MergeLayer.cpp
new file mode 100644
index 0000000000..1d4dc49379
--- /dev/null
+++ b/src/armnn/layers/MergeLayer.cpp
@@ -0,0 +1,65 @@
+//
+// Copyright © 2017 Arm Ltd. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+#include "MergeLayer.hpp"
+
+#include "LayerCloneBase.hpp"
+
+#include <backendsCommon/WorkloadData.hpp>
+#include <backendsCommon/WorkloadFactory.hpp>
+
+namespace armnn
+{
+
+MergeLayer::MergeLayer(const char* name)
+    : Layer(2, 1, LayerType::Merge, name)
+{}
+
+std::unique_ptr<IWorkload> MergeLayer::CreateWorkload(const Graph& graph,
+                                                      const IWorkloadFactory& factory) const
+{
+    return nullptr;
+}
+
+MergeLayer* MergeLayer::Clone(Graph& graph) const
+{
+    return CloneBase<MergeLayer>(graph, GetName());
+}
+
+void MergeLayer::ValidateTensorShapesFromInputs()
+{
+    VerifyLayerConnections(2, CHECK_LOCATION());
+
+    std::vector<TensorShape> inferredShapes = InferOutputShapes({
+        GetInputSlot(0).GetConnection()->GetTensorInfo().GetShape(),
+        GetInputSlot(1).GetConnection()->GetTensorInfo().GetShape(),
+    });
+
+    BOOST_ASSERT(inferredShapes.size() == 1);
+
+    ConditionalThrowIfNotEqual<LayerValidationException>(
+        "MergeLayer: TensorShape set on OutputSlot[0] does not match the inferred shape.",
+        GetOutputSlot(0).GetTensorInfo().GetShape(),
+        inferredShapes[0]);
+}
+
+std::vector<TensorShape> MergeLayer::InferOutputShapes(const std::vector<TensorShape>& inputShapes) const
+{
+    BOOST_ASSERT(inputShapes.size() == 2);
+
+    ConditionalThrowIfNotEqual<LayerValidationException>(
+        "MergeLayer: TensorShapes set on inputs do not match",
+        inputShapes[0],
+        inputShapes[1]
+    );
+
+    return {inputShapes[0]};
+}
+
+void MergeLayer::Accept(ILayerVisitor& visitor) const
+{
+    visitor.VisitMergeLayer(this, GetName());
+}
+
+} // namespace armnn
diff --git a/src/armnn/layers/MergeLayer.hpp b/src/armnn/layers/MergeLayer.hpp
new file mode 100644
index 0000000000..66664ca952
--- /dev/null
+++ b/src/armnn/layers/MergeLayer.hpp
@@ -0,0 +1,47 @@
+//
+// Copyright © 2017 Arm Ltd. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+#pragma once
+
+#include "Layer.hpp"
+
+namespace armnn
+{
+
+/// This layer dequantizes the input tensor.
+class MergeLayer : public Layer
+{
+public:
+    /// Makes a workload for the Merge type.
+    /// @param [in] graph The graph where this layer can be found.
+    /// @param [in] factory The workload factory which will create the workload.
+    /// @return A pointer to the created workload, or nullptr if not created.
+    virtual std::unique_ptr<IWorkload> CreateWorkload(const Graph& graph,
+                                                      const IWorkloadFactory& factory) const override;
+
+    /// Creates a dynamically-allocated copy of this layer.
+    /// @param [in] graph The graph into which this layer is being cloned.
+    MergeLayer* Clone(Graph& graph) const override;
+
+    /// Check if the input tensor shape(s)
+    /// will lead to a valid configuration of @ref MergeLayer.
+    void ValidateTensorShapesFromInputs() override;
+
+    /// Infers the output shapes from given input shapes.
+    /// @param [in] inputShapes The input shapes layer has.
+    /// @return A vector to the inferred output shape.
+    std::vector<TensorShape> InferOutputShapes(const std::vector<TensorShape>& inputShapes) const override;
+
+    void Accept(ILayerVisitor& visitor) const override;
+
+protected:
+    /// Constructor to create a MergeLayer.
+    /// @param [in] name Optional name for the layer.
+    MergeLayer(const char* name);
+
+    /// Default destructor
+    ~MergeLayer() = default;
+};
+
+} // namespace armnn