IVGCVSW-5816 Constant memory access

 * Add new class ManagedConstTensorHandle to Unmap when out of scope
 * Integrate into existing layers that have constants
 * Add unit tests

Signed-off-by: Francis Murtagh <francis.murtagh@arm.com>
Change-Id: I0a05e14e438804b37e9862e76b5ca329483f6b45

1 files changed, 9 insertions, 5 deletions

diff --git a/src/armnn/layers/Convolution2dLayer.cpp b/src/armnn/layers/Convolution2dLayer.cpp
index cf7cf0f129..d7a7a330ef 100644
--- a/src/armnn/layers/Convolution2dLayer.cpp
+++ b/src/armnn/layers/Convolution2dLayer.cpp
@@ -145,12 +145,14 @@ Layer::ConstantTensors Convolution2dLayer::GetConstantTensorsByRef()
 
 void Convolution2dLayer::Accept(ILayerVisitor& visitor) const
 {
-    ConstTensor weightsTensor(m_Weight->GetTensorInfo(), m_Weight->Map(true)) ;
-    Optional<ConstTensor> optionalBiasTensor = EmptyOptional();
+    ManagedConstTensorHandle managedWeight(m_Weight);
+    ConstTensor weightsTensor(managedWeight.GetTensorInfo(), managedWeight.Map());
 
+    Optional<ConstTensor> optionalBiasTensor = EmptyOptional();
+    ManagedConstTensorHandle managedBias(m_Bias);
     if (GetParameters().m_BiasEnabled)
     {
-        ConstTensor biasTensor(m_Bias->GetTensorInfo(), m_Bias->Map(true));
+        ConstTensor biasTensor(managedBias.GetTensorInfo(), managedBias.Map());
         optionalBiasTensor = Optional<ConstTensor>(biasTensor);
     }
 
@@ -159,11 +161,13 @@ void Convolution2dLayer::Accept(ILayerVisitor& visitor) const
 
 void Convolution2dLayer::ExecuteStrategy(IStrategy& strategy) const
 {
-    std::vector<armnn::ConstTensor> constTensors { {m_Weight->GetTensorInfo(), m_Weight->Map(true)} };
+    ManagedConstTensorHandle managedWeight(m_Weight);
+    std::vector<armnn::ConstTensor> constTensors { { managedWeight.GetTensorInfo(), managedWeight.Map() } };
 
+    ManagedConstTensorHandle managedBias(m_Bias);
     if (GetParameters().m_BiasEnabled)
     {
-        constTensors.emplace_back(ConstTensor(m_Bias->GetTensorInfo(), m_Bias->Map(true)));
+        constTensors.emplace_back(ConstTensor(managedBias.GetTensorInfo(), managedBias.Map()));
     }
 
     strategy.ExecuteStrategy(this, GetParameters(), constTensors, GetName());