IVGCVSW-6630 Add new method AddPrecompiledLayer() to INetwork

  * Add new method AddPrecompiledLayer() to INetwork
    with Comments noting it is for backend users.
  * Added unit test to SubgraphViewTests.cpp.
  * Bug fix and code refactor in Graph.cpp specifically around
    Graph::SubstituteSubgraph(SubgraphView& subgraph,
                              IConnectableLayer* substituteLayer)

Change-Id: If2d816e5109e48ce920bf92d8823b39130c23a16
Signed-off-by: Cathal Corbett <cathal.corbett@arm.com>

1 files changed, 85 insertions, 0 deletions

diff --git a/src/armnn/test/SubgraphViewTests.cpp b/src/armnn/test/SubgraphViewTests.cpp
index d270787968..4e509be78b 100644
--- a/src/armnn/test/SubgraphViewTests.cpp
+++ b/src/armnn/test/SubgraphViewTests.cpp
@@ -168,6 +168,91 @@ TEST_CASE("SingleInputSingleOutput")
     CHECK_EQ(preCompiledLayer->GetOutputSlot(0).GetConnection(0), subgraphOutputConn);
 }
 
+TEST_CASE("SingleInputSingleOutputAddPrecompiledLayerSubstituteSubgraph1")
+{
+    // Construct graph.
+    Graph graph;
+
+    Layer* const inputLayer = graph.AddLayer<InputLayer>(0, "input");
+
+    Convolution2dDescriptor convDescriptor;
+    Layer* const convLayer1 = graph.AddLayer<Convolution2dLayer>(convDescriptor, "conv1");
+    Layer* const convLayer2 = graph.AddLayer<Convolution2dLayer>(convDescriptor, "conv2");
+
+    Layer* const outputLayer = graph.AddLayer<OutputLayer>(0, "output");
+
+    inputLayer->GetOutputSlot(0).Connect(convLayer1->GetInputSlot(0));
+    convLayer1->GetOutputSlot(0).Connect(convLayer2->GetInputSlot(0));
+    convLayer2->GetOutputSlot(0).Connect(outputLayer->GetInputSlot(0));
+
+    // Construct sub-graph
+    SubgraphViewSelector::SubgraphViewPtr subgraph = CreateSubgraphViewFrom(CreateInputsFrom({convLayer1}),
+                                                                            CreateOutputsFrom({convLayer2}),
+                                                                            {});
+
+    // Save sub-graph connections for comparison after substitution
+    IOutputSlot* subgraphInputConn = subgraph->GetInputSlot(0)->GetConnection();
+    IInputSlot* subgraphOutputConn = subgraph->GetOutputSlot(0)->GetConnection(0);
+
+    PreCompiledDescriptor preCompiledDescriptor(1, 1);
+    CompiledBlobPtr compiledBlobPtr;
+    BackendId backend = Compute::CpuRef;
+
+    // Construct dummy pre-compiled layer
+    INetworkPtr network = INetwork::Create();
+    IConnectableLayer* preCompiledLayer = network->AddPrecompiledLayer(preCompiledDescriptor, compiledBlobPtr, backend);
+
+    // Substitute sub-graph with pre-compiled layer
+    graph.SubstituteSubgraph(*subgraph, preCompiledLayer);
+
+    // Check that connections are correct after substitution
+    CHECK_EQ(preCompiledLayer->GetInputSlot(0).GetConnection(), subgraphInputConn);
+    CHECK_EQ(preCompiledLayer->GetOutputSlot(0).GetConnection(0), subgraphOutputConn);
+}
+
+TEST_CASE("SingleInputSingleOutputAddPrecompiledLayerSubstituteSubgraph2")
+{
+    // Construct graph.
+    Graph graph;
+
+    Layer* const inputLayer = graph.AddLayer<InputLayer>(0, "input");
+
+    Convolution2dDescriptor convDescriptor;
+    Layer* const convLayer1 = graph.AddLayer<Convolution2dLayer>(convDescriptor, "conv1");
+    Layer* const convLayer2 = graph.AddLayer<Convolution2dLayer>(convDescriptor, "conv2");
+
+    Layer* const outputLayer = graph.AddLayer<OutputLayer>(0, "output");
+
+    inputLayer->GetOutputSlot(0).Connect(convLayer1->GetInputSlot(0));
+    convLayer1->GetOutputSlot(0).Connect(convLayer2->GetInputSlot(0));
+    convLayer2->GetOutputSlot(0).Connect(outputLayer->GetInputSlot(0));
+
+    // Construct sub-graph
+    SubgraphViewSelector::SubgraphViewPtr subgraph = CreateSubgraphViewFrom(CreateInputsFrom({convLayer1}),
+                                                                            CreateOutputsFrom({convLayer2}),
+                                                                            {});
+
+    // Save sub-graph connections for comparison after substitution
+    IOutputSlot* subgraphInputConn = subgraph->GetInputSlot(0)->GetConnection();
+    IInputSlot* subgraphOutputConn = subgraph->GetOutputSlot(0)->GetConnection(0);
+
+    PreCompiledDescriptor preCompiledDescriptor(1, 1);
+    CompiledBlobPtr compiledBlobPtr;
+    BackendId backend = Compute::CpuRef;
+
+    // Construct dummy pre-compiled layer
+    INetworkPtr network = INetwork::Create();
+    IConnectableLayer* preCompiledLayer = network->AddPrecompiledLayer(preCompiledDescriptor, compiledBlobPtr, backend);
+    SubgraphView substituteSubgraph(preCompiledLayer);
+
+    // Substitute sub-graph with pre-compiled layer
+    graph.SubstituteSubgraph(*subgraph, substituteSubgraph);
+
+    // Check that connections are correct after substitution
+    CHECK_EQ(preCompiledLayer->GetInputSlot(0).GetConnection(), subgraphInputConn);
+    CHECK_EQ(preCompiledLayer->GetOutputSlot(0).GetConnection(0), subgraphOutputConn);
+}
+
 TEST_CASE("SingleInputSingleOutputSubstituteGraph")
 {
     // Construct graph