IVGCVSW-2643 Add Serializer & Deserializer for Activation

 * Added ActivationLayer to Schema.fbs
 * Added Activation serialization and deserialization support
 * Added serialization and deserialization unit tests

Change-Id: Ib5df45f123674988b994ffe3f111d3fb57864912
Signed-off-by: Mike Kelly <mike.kelly@arm.com>

4 files changed, 159 insertions, 1 deletions

diff --git a/src/armnnSerializer/Schema.fbs b/src/armnnSerializer/Schema.fbs
index 1b7427b185..e81365166f 100644
--- a/src/armnnSerializer/Schema.fbs
+++ b/src/armnnSerializer/Schema.fbs
@@ -9,6 +9,19 @@ file_identifier "ARMN";
 
 file_extension "armnn";
 
+enum ActivationFunction : byte {
+    Sigmoid = 0,
+    TanH = 1,
+    Linear = 2,
+    ReLu = 3,
+    BoundedReLu = 4,
+    SoftReLu = 5,
+    LeakyReLu = 6,
+    Abs = 7,
+    Sqrt = 8,
+    Square = 9
+}
+
 enum DataType : byte {
     Float16 = 0,
     Float32 = 1,
@@ -76,7 +89,8 @@ enum LayerType : uint {
     Reshape = 5,
     Softmax = 6,
     Convolution2d = 7,
-    DepthwiseConvolution2d = 8
+    DepthwiseConvolution2d = 8,
+    Activation = 9
 }
 
 // Base layer table to be used as part of other layers
@@ -94,6 +108,17 @@ table BindableLayerBase {
 }
 
 // Table for each layer defined below
+table ActivationLayer {
+    base:LayerBase;
+    descriptor:ActivationDescriptor;
+}
+
+table ActivationDescriptor {
+    function:ActivationFunction = Sigmoid;
+    a:float;
+    b:float;
+}
+
 table AdditionLayer {
     base:LayerBase;
 }
@@ -201,6 +226,7 @@ table ReshapeDescriptor {
 }
 
 union Layer {
+    ActivationLayer,
     AdditionLayer,
     Convolution2dLayer,
     DepthwiseConvolution2dLayer,
diff --git a/src/armnnSerializer/Serializer.cpp b/src/armnnSerializer/Serializer.cpp
index b85c45aa10..bee1a3cdb5 100644
--- a/src/armnnSerializer/Serializer.cpp
+++ b/src/armnnSerializer/Serializer.cpp
@@ -22,6 +22,33 @@ namespace serializer = armnnSerializer;
 namespace armnnSerializer
 {
 
+serializer::ActivationFunction GetFlatBufferActivationFunction(armnn::ActivationFunction function)
+{
+    switch (function)
+    {
+        case armnn::ActivationFunction::Sigmoid:
+            return serializer::ActivationFunction::ActivationFunction_Sigmoid;
+        case armnn::ActivationFunction::TanH:
+            return serializer::ActivationFunction::ActivationFunction_TanH;
+        case armnn::ActivationFunction::Linear:
+            return serializer::ActivationFunction::ActivationFunction_Linear;
+        case armnn::ActivationFunction::ReLu:
+            return serializer::ActivationFunction::ActivationFunction_ReLu;
+        case armnn::ActivationFunction::BoundedReLu:
+            return serializer::ActivationFunction::ActivationFunction_BoundedReLu;
+        case armnn::ActivationFunction::LeakyReLu:
+            return serializer::ActivationFunction::ActivationFunction_LeakyReLu;
+        case armnn::ActivationFunction::Abs:
+            return serializer::ActivationFunction::ActivationFunction_Abs;
+        case armnn::ActivationFunction::Sqrt:
+            return serializer::ActivationFunction::ActivationFunction_Sqrt;
+        case armnn::ActivationFunction::Square:
+            return serializer::ActivationFunction::ActivationFunction_Square;
+        default:
+            return serializer::ActivationFunction::ActivationFunction_Sigmoid;
+    }
+}
+
 uint32_t SerializerVisitor::GetSerializedId(unsigned int guid)
 {
     std::pair<unsigned int, uint32_t> guidPair(guid, m_layerId);
@@ -78,6 +105,29 @@ void SerializerVisitor::VisitOutputLayer(const armnn::IConnectableLayer* layer,
     CreateAnyLayer(flatBufferOutputLayer.o, serializer::Layer::Layer_OutputLayer);
 }
 
+// Build FlatBuffer for Activation Layer
+void SerializerVisitor::VisitActivationLayer(const armnn::IConnectableLayer* layer,
+                                             const armnn::ActivationDescriptor& descriptor,
+                                             const char* name)
+{
+    // Create FlatBuffer BaseLayer
+    auto flatBufferBaseLayer = CreateLayerBase(layer, serializer::LayerType::LayerType_Activation);
+
+    // Create the FlatBuffer ActivationDescriptor
+    auto flatBufferDescriptor = CreateActivationDescriptor(m_flatBufferBuilder,
+                                                           GetFlatBufferActivationFunction(descriptor.m_Function),
+                                                           descriptor.m_A,
+                                                           descriptor.m_B);
+
+    // Create the FlatBuffer ActivationLayer
+    auto flatBufferAdditionLayer = CreateActivationLayer(m_flatBufferBuilder,
+                                                         flatBufferBaseLayer,
+                                                         flatBufferDescriptor);
+
+    // Add the AnyLayer to the FlatBufferLayers
+    CreateAnyLayer(flatBufferAdditionLayer.o, serializer::Layer::Layer_ActivationLayer);
+}
+
 // Build FlatBuffer for Addition Layer
 void SerializerVisitor::VisitAdditionLayer(const armnn::IConnectableLayer* layer, const char* name)
 {
diff --git a/src/armnnSerializer/Serializer.hpp b/src/armnnSerializer/Serializer.hpp
index aa765a2065..0c442e0788 100644
--- a/src/armnnSerializer/Serializer.hpp
+++ b/src/armnnSerializer/Serializer.hpp
@@ -42,6 +42,10 @@ public:
         return m_serializedLayers;
     }
 
+    void VisitActivationLayer(const armnn::IConnectableLayer* layer,
+                              const armnn::ActivationDescriptor& descriptor,
+                              const char* name = nullptr) override;
+
     void VisitAdditionLayer(const armnn::IConnectableLayer* layer,
                             const char* name = nullptr) override;
 
diff --git a/src/armnnSerializer/test/ActivationSerializationTests.cpp b/src/armnnSerializer/test/ActivationSerializationTests.cpp
new file mode 100644
index 0000000000..c20f2864f9
--- /dev/null
+++ b/src/armnnSerializer/test/ActivationSerializationTests.cpp
@@ -0,0 +1,78 @@
+//
+// Copyright © 2017 Arm Ltd. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+
+#include <armnnDeserializer/IDeserializer.hpp>
+#include <armnn/ArmNN.hpp>
+#include <armnn/INetwork.hpp>
+#include "../Serializer.hpp"
+#include <sstream>
+#include <boost/test/unit_test.hpp>
+
+BOOST_AUTO_TEST_SUITE(SerializerTests)
+
+BOOST_AUTO_TEST_CASE(ActivationSerialization)
+{
+    armnnDeserializer::IDeserializerPtr parser = armnnDeserializer::IDeserializer::Create();
+
+    armnn::TensorInfo inputInfo(armnn::TensorShape({1, 2, 2, 1}), armnn::DataType::Float32, 1.0f, 0);
+    armnn::TensorInfo outputInfo(armnn::TensorShape({1, 2, 2, 1}), armnn::DataType::Float32, 4.0f, 0);
+
+    // Construct network
+    armnn::INetworkPtr network = armnn::INetwork::Create();
+
+    armnn::ActivationDescriptor descriptor;
+    descriptor.m_Function = armnn::ActivationFunction::ReLu;
+    descriptor.m_A = 0;
+    descriptor.m_B = 0;
+
+    armnn::IConnectableLayer* const inputLayer      = network->AddInputLayer(0, "input");
+    armnn::IConnectableLayer* const activationLayer = network->AddActivationLayer(descriptor, "activation");
+    armnn::IConnectableLayer* const outputLayer     = network->AddOutputLayer(0, "output");
+
+    inputLayer->GetOutputSlot(0).Connect(activationLayer->GetInputSlot(0));
+    inputLayer->GetOutputSlot(0).SetTensorInfo(inputInfo);
+
+    activationLayer->GetOutputSlot(0).Connect(outputLayer->GetInputSlot(0));
+    activationLayer->GetOutputSlot(0).SetTensorInfo(outputInfo);
+
+    armnnSerializer::Serializer serializer;
+    serializer.Serialize(*network);
+
+    std::stringstream stream;
+    serializer.SaveSerializedToStream(stream);
+
+    std::string const serializerString{stream.str()};
+    std::vector<std::uint8_t> const serializerVector{serializerString.begin(), serializerString.end()};
+
+    armnn::INetworkPtr deserializedNetwork = parser->CreateNetworkFromBinary(serializerVector);
+
+    armnn::IRuntime::CreationOptions options; // default options
+    armnn::IRuntimePtr run = armnn::IRuntime::Create(options);
+    auto deserializedOptimized = Optimize(*deserializedNetwork, { armnn::Compute::CpuRef }, run->GetDeviceSpec());
+
+    armnn::NetworkId networkIdentifier;
+
+    // Load graph into runtime
+    run->LoadNetwork(networkIdentifier, std::move(deserializedOptimized));
+
+    std::vector<float> inputData {0.0f, -5.3f, 42.0f, -42.0f};
+    armnn::InputTensors inputTensors
+    {
+        {0, armnn::ConstTensor(run->GetInputTensorInfo(networkIdentifier, 0), inputData.data())}
+    };
+
+    std::vector<float> expectedOutputData {0.0f, 0.0f, 42.0f, 0.0f};
+
+    std::vector<float> outputData(4);
+    armnn::OutputTensors outputTensors
+    {
+        {0, armnn::Tensor(run->GetOutputTensorInfo(networkIdentifier, 0), outputData.data())}
+    };
+    run->EnqueueWorkload(networkIdentifier, inputTensors, outputTensors);
+    BOOST_CHECK_EQUAL_COLLECTIONS(outputData.begin(), outputData.end(),
+    expectedOutputData.begin(), expectedOutputData.end());
+}
+
+BOOST_AUTO_TEST_SUITE_END()