Fix graph copy memory spike

 * Change layer storage of ConstTensors to std::shared_ptr<ConstCpuTensorHandle>
 * Change clone to share ConstTensor rather than copy
 * Remove uses of non-const GetTensor() call
 * Reduce scope of non-optimized network in ExeNet, so memory can be released after use

Signed-off-by: Finn Williams <Finn.Williams@arm.com>

Change-Id: Ibb2c7309d12411d21405bd6024c76bcdf5404545

1 files changed, 12 insertions, 12 deletions

diff --git a/src/armnn/layers/QuantizedLstmLayer.hpp b/src/armnn/layers/QuantizedLstmLayer.hpp
index 544acbd816..ca97a6bb65 100644
--- a/src/armnn/layers/QuantizedLstmLayer.hpp
+++ b/src/armnn/layers/QuantizedLstmLayer.hpp
@@ -14,31 +14,31 @@ class ScopedCpuTensorHandle;
 struct QuantizedLstmParameters
 {
     /// A unique pointer to represent 2D weights tensor with dimensions [outputSize, inputSize] (QAsymm8).
-    std::unique_ptr<ScopedCpuTensorHandle> m_InputToInputWeights;
+    std::shared_ptr<ConstCpuTensorHandle> m_InputToInputWeights;
     /// A unique pointer to represent 2D weights tensor with dimensions [outputSize, inputSize] (QAsymm8).
-    std::unique_ptr<ScopedCpuTensorHandle> m_InputToForgetWeights;
+    std::shared_ptr<ConstCpuTensorHandle> m_InputToForgetWeights;
     /// A unique pointer to represent 2D weights tensor with dimensions [outputSize, inputSize] (QAsymm8).
-    std::unique_ptr<ScopedCpuTensorHandle> m_InputToCellWeights;
+    std::shared_ptr<ConstCpuTensorHandle> m_InputToCellWeights;
     /// A unique pointer to represent 2D weights tensor with dimensions [outputSize, inputSize] (QAsymm8).
-    std::unique_ptr<ScopedCpuTensorHandle> m_InputToOutputWeights;
+    std::shared_ptr<ConstCpuTensorHandle> m_InputToOutputWeights;
 
     /// A unique pointer to represent 2D weights tensor with dimensions [outputSize, outputSize] (QAsymm8).
-    std::unique_ptr<ScopedCpuTensorHandle> m_RecurrentToInputWeights;
+    std::shared_ptr<ConstCpuTensorHandle> m_RecurrentToInputWeights;
     /// A unique pointer to represent 2D weights tensor with dimensions [outputSize, outputSize] (QAsymm8).
-    std::unique_ptr<ScopedCpuTensorHandle> m_RecurrentToForgetWeights;
+    std::shared_ptr<ConstCpuTensorHandle> m_RecurrentToForgetWeights;
     /// A unique pointer to represent 2D weights tensor with dimensions [outputSize, outputSize] (QAsymm8).
-    std::unique_ptr<ScopedCpuTensorHandle> m_RecurrentToCellWeights;
+    std::shared_ptr<ConstCpuTensorHandle> m_RecurrentToCellWeights;
     /// A unique pointer to represent 2D weights tensor with dimensions [outputSize, outputSize] (QAsymm8).
-    std::unique_ptr<ScopedCpuTensorHandle> m_RecurrentToOutputWeights;
+    std::shared_ptr<ConstCpuTensorHandle> m_RecurrentToOutputWeights;
 
     /// A unique pointer to represent 1D bias tensor with dimensions [outputSize] (int32).
-    std::unique_ptr<ScopedCpuTensorHandle> m_InputGateBias;
+    std::shared_ptr<ConstCpuTensorHandle> m_InputGateBias;
     /// A unique pointer to represent 1D bias tensor with dimensions [outputSize] (int32).
-    std::unique_ptr<ScopedCpuTensorHandle> m_ForgetGateBias;
+    std::shared_ptr<ConstCpuTensorHandle> m_ForgetGateBias;
     /// A unique pointer to represent 1D bias tensor with dimensions [outputSize] (int32).
-    std::unique_ptr<ScopedCpuTensorHandle> m_CellBias;
+    std::shared_ptr<ConstCpuTensorHandle> m_CellBias;
     /// A unique pointer to represent 1D bias tensor with dimensions [outputSize] (int32).
-    std::unique_ptr<ScopedCpuTensorHandle> m_OutputGateBias;
+    std::shared_ptr<ConstCpuTensorHandle> m_OutputGateBias;
 };
 
 /// This layer represents a QuantizedLstm operation.