IVGCVSW-3268 Add Reference workload support for the new Prelu Activation layer

 * Added reference workload for the PReLU Activation layer
 * Added factory methods
 * Added validation support
 * Added Int16 support
 * Added unit tests

Change-Id: Ic950d908c5e0a335dccd2960a3ffab0f8b599876
Signed-off-by: Matteo Martincigh <matteo.martincigh@arm.com>

1 files changed, 35 insertions, 0 deletions

diff --git a/src/backends/reference/workloads/PreluImpl.cpp b/src/backends/reference/workloads/PreluImpl.cpp
new file mode 100644
index 0000000000..458025bb0a
--- /dev/null
+++ b/src/backends/reference/workloads/PreluImpl.cpp
@@ -0,0 +1,35 @@
+//
+// Copyright © 2017 Arm Ltd. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+
+#include "PreluImpl.hpp"
+#include "RefWorkloadUtils.hpp"
+#include "Broadcast.hpp"
+
+namespace armnn
+{
+
+void PreluImpl(const PreluQueueDescriptor& data,
+               Decoder<float>& inputData,
+               Decoder<float>& alphaData,
+               Encoder<float>& outputData)
+{
+    const TensorInfo& inputInfo  = GetTensorInfo(data.m_Inputs[0]);
+    const TensorInfo& alphaInfo  = GetTensorInfo(data.m_Inputs[1]);
+    const TensorInfo& outputInfo = GetTensorInfo(data.m_Outputs[0]);
+
+    const TensorShape& inputShape  = inputInfo.GetShape();
+    const TensorShape& alphaShape  = alphaInfo.GetShape();
+    const TensorShape& outputShape = outputInfo.GetShape();
+
+    // PReLU activation: f(x) = alpha * x for x < 0, f(x) = x for x >= 0
+    auto prelu = [](float x, float alpha)
+    {
+        return x < 0 ? alpha * x : x;
+    };
+
+    BroadcastLoop(inputShape, alphaShape, outputShape).Unroll(prelu, 0, inputData, alphaData, outputData);
+}
+
+} // namespace armnn