IVGCVSW-7830 Add backend optimizations to remove Reshapes where possible

 * Added optimization to remove reshapes for Neon and Ref Backends
   by using overridden TensorInfos
 * Added ability to delete Subgraphs during Optimization
 * Fixed naming error in NeonEndToEndTests and CLEndToEndTests
 * Added LayerNameAndTypeCheck for testing.
 * Fixed error where layers were not marked as altered when removed in
   CLBackend

Signed-off-by: Mike Kelly <mike.kelly@arm.com>
Change-Id: I1ac25cd4ec9821470d961831ae2c8d24882276cc

8 files changed, 78 insertions, 15 deletions

diff --git a/src/armnn/Graph.cpp b/src/armnn/Graph.cpp
index fee1da4343..cf6f20f82b 100644
--- a/src/armnn/Graph.cpp
+++ b/src/armnn/Graph.cpp
@@ -508,12 +508,22 @@ void Graph::ReplaceSubgraphConnections(const SubgraphView& subgraph, const Subgr
         if (subgraphInputSlot->GetConnection())
         {
             IOutputSlot* connectedOutputSlot = subgraphInputSlot->GetConnection();
+            InputSlot* inputSlot = PolymorphicDowncast<InputSlot*>(subgraphInputSlot);
+            bool isOverridden = inputSlot->IsTensorInfoOverridden();
+
             ARMNN_ASSERT(connectedOutputSlot);
             connectedOutputSlot->Disconnect(*subgraphInputSlot);
 
             IInputSlot* substituteInputSlot = substituteSubgraphInputSlots.at(inputSlotIdx);
             ARMNN_ASSERT(substituteInputSlot);
             connectedOutputSlot->Connect(*substituteInputSlot);
+
+            if (isOverridden)
+            {
+                TensorInfo overridden = inputSlot->GetTensorInfo();
+                InputSlot* newInputSlot = PolymorphicDowncast<InputSlot*>(substituteInputSlot);
+                newInputSlot->SetTensorInfo(overridden);
+            }
         }
     }
 
diff --git a/src/armnn/Layer.cpp b/src/armnn/Layer.cpp
index 8d4811ae89..d2f8f2c982 100644
--- a/src/armnn/Layer.cpp
+++ b/src/armnn/Layer.cpp
@@ -259,7 +259,20 @@ void Layer::CollectWorkloadInputs(WorkloadDataCollector& dataCollector) const
         // The graph must be well-formed at this point.
         ARMNN_ASSERT(inputSlot.GetConnection());
         const OutputHandler& outputHandler = inputSlot.GetConnectedOutputSlot()->GetOutputHandler();
-        dataCollector.Push(outputHandler.GetData(), outputHandler.GetTensorInfo());
+
+        if (inputSlot.IsTensorInfoOverridden() && outputHandler.GetData())
+        {
+            auto handler = outputHandler.GetData()->DecorateTensorHandle(inputSlot.GetTensorInfo());
+
+            if (handler)
+            {
+                // Add overridden TensorHandle
+                dataCollector.Push(handler.get(), inputSlot.GetTensorInfo());
+                continue;
+            }
+        }
+        // Add default TensorHandle
+        dataCollector.Push(outputHandler.GetData(), inputSlot.GetTensorInfo());
     }
 }
 
diff --git a/src/armnn/Layer.hpp b/src/armnn/Layer.hpp
index 5e097f0fad..4f69e78b62 100644
--- a/src/armnn/Layer.hpp
+++ b/src/armnn/Layer.hpp
@@ -80,15 +80,15 @@ public:
 
     /// Sets the TensorInfo for this InputSlot. This can be used to override the TensorInfo and if set will be returned
     /// instead of the TensorInfo for the Connected OutputSlot.
-    void SetTensorInfo(const TensorInfo tensorInfo);
+    void SetTensorInfo(const TensorInfo tensorInfo) override;
     /// Gets the TensorInfo for this InputSlot. If the InputSlot's TensorInfo has not been set then this will get the
     /// TensorInfo from the Connected TensorInfo.
-    const TensorInfo& GetTensorInfo() const;
+    const TensorInfo& GetTensorInfo() const override;
     /// Returns true if this InputSlot either has an overridden TensorInfo for this InputSlot that was set through a
     /// call to SetTensorInfo() or is Connected to an OutputSlot that has its TensorInfo set.
-    bool IsTensorInfoSet() const;
+    bool IsTensorInfoSet() const override;
     /// Returns true if this InputSlot has an overridden TensorInfo that was set through a call to SetTensorInfo().
-    bool IsTensorInfoOverridden() const;
+    bool IsTensorInfoOverridden() const override;
 
 private:
     Layer& m_OwningLayer;
diff --git a/src/armnn/LoadedNetwork.cpp b/src/armnn/LoadedNetwork.cpp
index 3f4aa34a5b..3d84054b69 100644
--- a/src/armnn/LoadedNetwork.cpp
+++ b/src/armnn/LoadedNetwork.cpp
@@ -955,10 +955,10 @@ Status LoadedNetwork::EnqueueWorkload(const InputTensors& inputTensors,
                 syncDesc.m_Inputs.push_back(inputTensorHandle);
                 WorkloadInfo info;
                 info.m_InputTensorInfos.push_back(
-                        outputLayer->GetInputSlot(0).GetConnectedOutputSlot()->GetTensorInfo());
+                        outputLayer->GetInputSlot(0).GetTensorInfo());
                 auto syncWorkload = std::make_unique<SyncMemGenericWorkload>(syncDesc, info);
                 ARMNN_ASSERT_MSG(syncWorkload, "No sync workload created");
-                m_OutputQueue.push_back(move(syncWorkload));
+                m_OutputQueue.push_back(std::move(syncWorkload));
                 importedOutputIdIndex++;
             }
             else
@@ -1089,7 +1089,7 @@ void LoadedNetwork::EnqueueInput(const BindableLayer& layer, ITensorHandle* tens
             timelineUtils->Commit();
         }
 
-        m_InputQueue.push_back(move(inputWorkload));
+        m_InputQueue.push_back(std::move(inputWorkload));
     }
 }
 
@@ -1149,7 +1149,7 @@ void LoadedNetwork::EnqueueOutput(const BindableLayer& layer, ITensorHandle* ten
                     info.m_InputTensorInfos.push_back(inputTensorInfo);
                     auto syncWorkload = std::make_unique<SyncMemGenericWorkload>(syncDesc, info);
                     ARMNN_ASSERT_MSG(syncWorkload, "No sync workload created");
-                    m_OutputQueue.push_back(move(syncWorkload));
+                    m_OutputQueue.push_back(std::move(syncWorkload));
                 }
                 else
                 {
@@ -1177,7 +1177,7 @@ void LoadedNetwork::EnqueueOutput(const BindableLayer& layer, ITensorHandle* ten
             timelineUtils->Commit();
         }
 
-        m_OutputQueue.push_back(move(outputWorkload));
+        m_OutputQueue.push_back(std::move(outputWorkload));
     }
 }
 
@@ -1650,7 +1650,7 @@ std::vector<ImportedOutputId> LoadedNetwork::ImportOutputs(const OutputTensors&
 
         const InputSlot& inputSlot = layer->GetInputSlots()[0];
         ITensorHandleFactory::FactoryId factoryId = inputSlot.GetConnectedOutputSlot()->GetTensorHandleFactoryId();
-        const TensorInfo& tensorInfo = inputSlot.GetConnectedOutputSlot()->GetTensorInfo();
+        const TensorInfo& tensorInfo = inputSlot.GetTensorInfo();
 
         ITensorHandleFactory* handleFactory = m_TensorHandleFactoryRegistry.GetFactory(factoryId);
         ARMNN_ASSERT(handleFactory);
@@ -2093,6 +2093,14 @@ std::unique_ptr<IWorkingMemHandle> LoadedNetwork::CreateWorkingMemHandle(Network
             if (found != m_ConstantTensorHandles.end())
             {
                 ITensorHandle* tensorHandle = found->second;
+                if (slot.IsTensorInfoOverridden())
+                {
+                    ITensorHandle* decorated = tensorHandle->DecorateTensorHandle(slot.GetTensorInfo()).get();
+                    if (decorated)
+                    {
+                        tensorHandle = decorated;
+                    }
+                }
                 workingMemDescriptor.m_Inputs.push_back(tensorHandle);
 
                 // Odd case where a constant layer is connected to an output layer
@@ -2113,6 +2121,14 @@ std::unique_ptr<IWorkingMemHandle> LoadedNetwork::CreateWorkingMemHandle(Network
             HandleInfo& handleInfo = outputToHandleInfoMap.at(outputSlot);
 
             ITensorHandle* inputTensorHandle = handleInfo.m_TensorHandle;
+            if (slot.IsTensorInfoOverridden())
+            {
+                ITensorHandle* decorated = inputTensorHandle->DecorateTensorHandle(slot.GetTensorInfo()).get();
+                if (decorated)
+                {
+                    inputTensorHandle = decorated;
+                }
+            }
             workingMemDescriptor.m_Inputs.push_back(inputTensorHandle);
 
             // Store the LayerBindingId of the OutputLayer
diff --git a/src/armnn/Network.cpp b/src/armnn/Network.cpp
index 2abaf44587..ae5bde17ca 100644
--- a/src/armnn/Network.cpp
+++ b/src/armnn/Network.cpp
@@ -1310,6 +1310,28 @@ OptimizationResult ApplyBackendOptimizations(OptimizedNetworkImpl* optNetObjPtr,
                     });
             }
 
+            // Remove deleted sub-graphs
+            for (auto& deletedSubgraph : optimizationViews.GetDeletedSubgraphs())
+            {
+                for (auto& l : deletedSubgraph.GetIConnectableLayers())
+                {
+                    Layer* deletedLayer = PolymorphicDowncast<Layer*>(l);
+                    for (unsigned int in = deletedLayer->GetNumInputSlots(); in > 0; --in)
+                    {
+                        auto inputSlot = deletedLayer->GetInputSlot(in -1);
+                        OutputSlot* parentOut = inputSlot.GetConnectedOutputSlot();
+                        parentOut->Disconnect(inputSlot);
+                        for (unsigned int out = deletedLayer->GetOutputSlot(in -1).GetNumConnections(); out > 0; --out)
+                        {
+                            InputSlot *childIn = deletedLayer->GetOutputSlot(in - 1).GetConnection(out -1);
+                            deletedLayer->GetOutputSlot(in - 1).Disconnect(*childIn);
+                            parentOut->Connect(*childIn);
+                        }
+                    }
+                    optGraph.EraseLayer(deletedLayer);
+                }
+            }
+
             if (!optimizationViews.GetFailedSubgraphs().empty())
             {
                 std::stringstream warningMsg;
diff --git a/src/armnn/layers/ConcatLayer.cpp b/src/armnn/layers/ConcatLayer.cpp
index 7a1b689b2c..4629bf245e 100644
--- a/src/armnn/layers/ConcatLayer.cpp
+++ b/src/armnn/layers/ConcatLayer.cpp
@@ -120,7 +120,7 @@ void ConcatLayer::CreateTensors(const TensorHandleFactoryRegistry& registry,
                     // 3) the input does not come from a Constant layer or input layer
                     // 4) the input is only read by this concat layer
                     // 5) if concat along x or y (2 innermost dimensions) and the previous layers do not require padding
-                    // 6) the input does not have an Overridden TensorInfo
+                    // 6) neither the inputs nor the output have an Overridden TensorInfo
                     if (slot &&
                         parentInfo.IsTypeSpaceMatch(info) && //(1)
                         factoryId == slot->GetTensorHandleFactoryId() && //(2)
@@ -128,6 +128,7 @@ void ConcatLayer::CreateTensors(const TensorHandleFactoryRegistry& registry,
                         slot->GetOwningLayer().GetType() != LayerType::Input && //(3)
                         slot->GetNumConnections() == 1 &&
                         canUseSubTensorOnXorY && //(5)
+                        !GetOutputSlot(0).GetConnection(0)->IsTensorInfoOverridden() && //(6)
                         !currentLayer->GetInputSlot(i).IsTensorInfoOverridden()) //(6)
                     {
                         ARMNN_NO_DEPRECATE_WARN_BEGIN
diff --git a/src/armnn/layers/ReverseV2Layer.cpp b/src/armnn/layers/ReverseV2Layer.cpp
index 29f8b1b781..201e19819b 100644
--- a/src/armnn/layers/ReverseV2Layer.cpp
+++ b/src/armnn/layers/ReverseV2Layer.cpp
@@ -40,7 +40,7 @@ void ReverseV2Layer::ValidateTensorShapesFromInputs()
     VerifyShapeInferenceType(outputShape, m_ShapeInferenceMethod);
 
     auto inferredShapes = InferOutputShapes({
-        GetInputSlot(0).GetConnection()->GetTensorInfo().GetShape() });
+        GetInputSlot(0).GetTensorInfo().GetShape() });
 
     ARMNN_ASSERT(inferredShapes.size() == 1);
 
diff --git a/src/armnn/layers/SplitterLayer.cpp b/src/armnn/layers/SplitterLayer.cpp
index 86a42305ff..dc8864a736 100644
--- a/src/armnn/layers/SplitterLayer.cpp
+++ b/src/armnn/layers/SplitterLayer.cpp
@@ -131,13 +131,14 @@ void SplitterLayer::CreateTensors(const TensorHandleFactoryRegistry& registry,
                 // 2) the same TensorHandleFactory is used for input and split layer output
                 // 3) the output does not go to a Constant layer or input layer
                 // 4) if split along x or y (2 innermost dimensions) and the next layers do not require padding
-                // 5) none of the outputs have an Overridden TensorInfo
+                // 5) neither the input nor the outputs have an Overridden TensorInfo
                 if (parentInfo.IsTypeSpaceMatch(info) && //(1)
                     factoryId == slot->GetTensorHandleFactoryId() && //(2)
                     GetOutputSlot(i).GetConnection(0)->GetOwningLayer().GetType() != LayerType::Constant && //(3)
                     GetOutputSlot(i).GetConnection(0)->GetOwningLayer().GetType() != LayerType::Input && //(3)
                     canUseSubTensorOnXorY && //(4)
-                    !GetOutputSlot(i).GetConnection(0)->IsTensorInfoOverridden()) //(5)
+                    !GetOutputSlot(i).GetConnection(0)->IsTensorInfoOverridden() && //(5)
+                    !GetInputSlot(0).IsTensorInfoOverridden()) //(5)
                 {
                     ARMNN_NO_DEPRECATE_WARN_BEGIN
                     return factory.CreateSubTensorHandle(*inputData,