IVGCVSW-7555 Restructure Delegate

* New folders created:
  * common is for common code where TfLite API is not used
  * classic is for existing delegate implementations
  * opaque is for new opaque delegate implementation,
  * tests is for shared between existing Delegate and Opaque Delegate which have test utils to work which delegate to use.
* Existing delegate is built to libarmnnDelegate.so and opaque delegate is built as libarmnnOpaqueDelegate.so
* Opaque structure is introduced but no API is added yet.
* CmakeList.txt and delegate/CMakeList.txt have been modified and 2 new CmakeList.txt added
* Rename BUILD_ARMNN_TFLITE_DELEGATE as BUILD_CLASSIC_DELEGATE
* Rename BUILD_ARMNN_TFLITE_OPAQUE_DELEGATE as BUILD_OPAQUE_DELEGATE

Signed-off-by: Teresa Charlin <teresa.charlinreyes@arm.com>
Change-Id: Ib682b9ad0ac8d8acdc4ec6d9099bb0008a9fe8ed
diff --git a/delegate/classic/src/Lstm.hpp b/delegate/classic/src/Lstm.hpp
new file mode 100644
index 0000000..460c61a
--- /dev/null
+++ b/delegate/classic/src/Lstm.hpp
@@ -0,0 +1,268 @@
+//
+// Copyright © 2022-2023 Arm Ltd and Contributors. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+
+#pragma once
+
+#include <DelegateUtils.hpp>
+
+#include <armnn/LstmParams.hpp>
+#include <armnn/Tensor.hpp>
+#include <armnn/utility/IgnoreUnused.hpp>
+
+#include <tensorflow/lite/builtin_ops.h>
+#include <tensorflow/lite/c/builtin_op_data.h>
+#include <tensorflow/lite/c/common.h>
+#include <tensorflow/lite/minimal_logging.h>
+
+namespace armnnDelegate
+{
+
+TfLiteStatus VisitLstmOperator(DelegateData& delegateData,
+                               TfLiteContext* tfLiteContext,
+                               TfLiteNode* tfLiteNode,
+                               int nodeIndex,
+                               int32_t operatorCode)
+{
+    auto numInputs = tfLiteNode->inputs->size;
+    if (numInputs < 2)
+    {
+        TF_LITE_MAYBE_KERNEL_LOG(
+                tfLiteContext, "TfLiteArmnnDelegate: Minimum number of inputs (%d != %d) in node #%d",
+                2, numInputs, nodeIndex);
+        return kTfLiteError;
+    }
+
+    const auto nodeParams = reinterpret_cast<TfLiteLSTMParams*>(tfLiteNode->builtin_data);
+    const TfLiteTensor* tfLiteTensors = tfLiteContext->tensors;
+
+    const TfLiteTensor& tfLiteInputTensor = tfLiteTensors[tfLiteNode->inputs->data[0]];
+    if (!IsValid(tfLiteContext, tfLiteInputTensor, operatorCode, nodeIndex))
+    {
+        return kTfLiteError;
+    }
+
+    const TfLiteTensor& tfLiteOutputTensor = tfLiteTensors[tfLiteNode->outputs->data[0]];
+    if (!IsValid(tfLiteContext, tfLiteOutputTensor, operatorCode, nodeIndex))
+    {
+        return kTfLiteError;
+    }
+
+    // Set the params structure for the AddLstmLayer call
+    armnn::LstmInputParams params;
+
+    if (IsOptionalOperandPresent(tfLiteNode, 1))
+    {
+        params.m_InputToInputWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 1);
+    }
+
+    params.m_InputToForgetWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 2);
+    params.m_InputToCellWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 3);
+    params.m_InputToOutputWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 4);
+
+    // Recurrent weight tensors of size {n_cell, n_output}
+    if (IsOptionalOperandPresent(tfLiteNode, 5))
+    {
+        params.m_RecurrentToInputWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 5);
+    }
+
+    params.m_RecurrentToForgetWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 6);
+    params.m_RecurrentToCellWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 7);
+    params.m_RecurrentToOutputWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 8);
+
+    // Peephole weights tensors of size {n_cell}, representing a diagonal matrix.
+    if (IsOptionalOperandPresent(tfLiteNode, 9))
+    {
+        params.m_CellToInputWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 9);
+    }
+
+    if (IsOptionalOperandPresent(tfLiteNode, 10))
+    {
+        params.m_CellToForgetWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 10);
+    }
+
+    if (IsOptionalOperandPresent(tfLiteNode, 11))
+    {
+        params.m_CellToOutputWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 11);
+    }
+
+    // Gates bias tensors of size {n_cell}
+    if (IsOptionalOperandPresent(tfLiteNode, 12))
+    {
+        params.m_InputGateBias = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 12);
+    }
+
+    params.m_ForgetGateBias = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 13);
+    params.m_CellBias = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 14);
+    params.m_OutputGateBias = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 15);
+
+    // Projection weight tensor of size {n_output, n_cell}
+    if (IsOptionalOperandPresent(tfLiteNode, 16))
+    {
+        params.m_ProjectionWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 16);
+    }
+    // Projection bias tensor of size {n_output}
+    if (IsOptionalOperandPresent(tfLiteNode, 17))
+    {
+        params.m_ProjectionBias = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 17);
+    }
+
+    // These state tensors are defined as variable tensors, and will be modified by this op.
+    armnn::TensorInfo outputStateInInfo = GetTensorInfoForTfLiteTensor(tfLiteTensors[tfLiteNode->inputs->data[18]]);
+    armnn::TensorInfo cellStateInInfo = GetTensorInfoForTfLiteTensor(tfLiteTensors[tfLiteNode->inputs->data[19]]);
+
+    // Layer norm coefficient tensors of size {n_cell}, representing a diagonal matrix.
+    if (IsOptionalOperandPresent(tfLiteNode, 20))
+    {
+        params.m_InputLayerNormWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 20);
+    }
+
+    if (IsOptionalOperandPresent(tfLiteNode, 21))
+    {
+        params.m_ForgetLayerNormWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 21);
+    }
+
+    if (IsOptionalOperandPresent(tfLiteNode, 22))
+    {
+        params.m_CellLayerNormWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 22);
+    }
+
+    if (IsOptionalOperandPresent(tfLiteNode, 23))
+    {
+        params.m_OutputLayerNormWeights = GetConstTensorForTfLiteTensor(tfLiteTensors, tfLiteNode, 23);
+    }
+
+    // set the layer descriptor
+    armnn::LstmDescriptor desc;
+    desc.m_ActivationFunc    = NonNegative(nodeParams->activation, nodeIndex);
+    desc.m_ClippingThresCell = nodeParams->cell_clip;
+    desc.m_ClippingThresProj = nodeParams->proj_clip;
+    desc.m_CifgEnabled       = (params.m_InputToInputWeights == nullptr
+                                || params.m_RecurrentToInputWeights == nullptr
+                                || params.m_InputGateBias == nullptr);
+    desc.m_PeepholeEnabled   = (params.m_CellToForgetWeights != nullptr || params.m_CellToOutputWeights != nullptr);
+    desc.m_ProjectionEnabled = (params.m_ProjectionWeights != nullptr);
+    desc.m_LayerNormEnabled  = (params.m_InputLayerNormWeights != nullptr
+                                || params.m_ForgetLayerNormWeights != nullptr
+                                || params.m_CellLayerNormWeights != nullptr
+                                || params.m_OutputLayerNormWeights != nullptr);
+
+    const armnn::TensorInfo& inputTensorInfo = GetTensorInfoForTfLiteTensor(tfLiteInputTensor);
+    const armnn::TensorInfo& outputTensorInfo = GetTensorInfoForTfLiteTensor(tfLiteOutputTensor, true);
+
+    unsigned int batchSize  = inputTensorInfo.GetShape()[0];
+    unsigned int outputSize = outputTensorInfo.GetShape()[1];
+    unsigned int numUnits   = cellStateInInfo.GetShape()[1];
+
+    armnn::DataType dataType = inputTensorInfo.GetDataType();
+    float qScale = inputTensorInfo.GetQuantizationScale();
+    float qOffset = inputTensorInfo.GetQuantizationOffset();
+
+    armnn::TensorInfo scratchBufferTensorInfo({batchSize, numUnits * 3}, dataType, qScale, qOffset);
+    if (!desc.m_CifgEnabled)
+    {
+        scratchBufferTensorInfo = armnn::TensorInfo({batchSize, numUnits * 4}, dataType, qScale, qOffset);
+    }
+    armnn::TensorInfo cellStateOutTensorInfo({batchSize, numUnits}, dataType, qScale, qOffset);
+    armnn::TensorInfo outputStateOutTensorInfo({batchSize, outputSize}, dataType, qScale, qOffset);
+
+    armnn::LstmInputParamsInfo paramsInfo;
+    paramsInfo.m_InputToForgetWeights     = &(params.m_InputToForgetWeights->GetInfo());
+    paramsInfo.m_InputToCellWeights       = &(params.m_InputToCellWeights->GetInfo());
+    paramsInfo.m_InputToOutputWeights     = &(params.m_InputToOutputWeights->GetInfo());
+    paramsInfo.m_RecurrentToForgetWeights = &(params.m_RecurrentToForgetWeights->GetInfo());
+    paramsInfo.m_RecurrentToCellWeights   = &(params.m_RecurrentToCellWeights->GetInfo());
+    paramsInfo.m_RecurrentToOutputWeights = &(params.m_RecurrentToOutputWeights->GetInfo());
+    paramsInfo.m_ForgetGateBias           = &(params.m_ForgetGateBias->GetInfo());
+    paramsInfo.m_CellBias                 = &(params.m_CellBias->GetInfo());
+    paramsInfo.m_OutputGateBias           = &(params.m_OutputGateBias->GetInfo());
+
+    if (!desc.m_CifgEnabled)
+    {
+        paramsInfo.m_InputToInputWeights = &(params.m_InputToInputWeights->GetInfo());
+        paramsInfo.m_RecurrentToInputWeights = &(params.m_RecurrentToInputWeights->GetInfo());
+        if (params.m_CellToInputWeights != nullptr)
+        {
+            paramsInfo.m_CellToInputWeights = &(params.m_CellToInputWeights->GetInfo());
+        }
+        paramsInfo.m_InputGateBias = &(params.m_InputGateBias->GetInfo());
+    }
+
+    if (desc.m_ProjectionEnabled)
+    {
+        paramsInfo.m_ProjectionWeights = &(params.m_ProjectionWeights->GetInfo());
+        if (params.m_ProjectionBias != nullptr)
+        {
+            paramsInfo.m_ProjectionBias = &(params.m_ProjectionBias->GetInfo());
+        }
+    }
+
+    if (desc.m_PeepholeEnabled)
+    {
+        paramsInfo.m_CellToForgetWeights = &(params.m_CellToForgetWeights->GetInfo());
+        paramsInfo.m_CellToOutputWeights = &(params.m_CellToOutputWeights->GetInfo());
+    }
+
+    if (desc.m_LayerNormEnabled)
+    {
+        if(!desc.m_CifgEnabled)
+        {
+            paramsInfo.m_InputLayerNormWeights = &(params.m_InputLayerNormWeights->GetInfo());
+        }
+        paramsInfo.m_ForgetLayerNormWeights = &(params.m_ForgetLayerNormWeights->GetInfo());
+        paramsInfo.m_CellLayerNormWeights = &(params.m_CellLayerNormWeights->GetInfo());
+        paramsInfo.m_OutputLayerNormWeights = &(params.m_OutputLayerNormWeights->GetInfo());
+    }
+
+    bool isSupported = false;
+    armnn::BackendId setBackend;
+    auto validateFunc = [&](const armnn::TensorInfo& outputInfo, bool& isSupported)
+    {
+        FORWARD_LAYER_SUPPORT_FUNC("LSTM",
+                                   tfLiteContext,
+                                   IsLstmSupported,
+                                   delegateData.m_Backends,
+                                   isSupported,
+                                   setBackend,
+                                   inputTensorInfo,
+                                   outputStateInInfo,
+                                   cellStateInInfo,
+                                   scratchBufferTensorInfo,
+                                   outputStateOutTensorInfo,
+                                   cellStateOutTensorInfo,
+                                   outputInfo,
+                                   desc,
+                                   paramsInfo);
+    };
+
+    if (!delegateData.m_Network)
+    {
+        validateFunc(outputTensorInfo, isSupported);
+        return isSupported ? kTfLiteOk : kTfLiteError;
+    }
+
+    armnn::IConnectableLayer* layer = delegateData.m_Network->AddLstmLayer(desc, params);
+    layer->SetBackendId(setBackend);
+    ARMNN_ASSERT(layer != nullptr);
+
+    layer->GetOutputSlot(0).SetTensorInfo(scratchBufferTensorInfo);
+    layer->GetOutputSlot(1).SetTensorInfo(outputStateOutTensorInfo);
+    layer->GetOutputSlot(2).SetTensorInfo(cellStateOutTensorInfo);
+    layer->GetOutputSlot(3).SetTensorInfo(outputTensorInfo);
+
+    // Connect the inputs
+    // input_layer
+    delegateData.m_OutputSlotForNode[tfLiteNode->inputs->data[0]]->Connect(layer->GetInputSlot(0));
+    // cellStateIn
+    delegateData.m_OutputSlotForNode[tfLiteNode->inputs->data[18]]->Connect(layer->GetInputSlot(1));
+    //outputStateIn
+    delegateData.m_OutputSlotForNode[tfLiteNode->inputs->data[19]]->Connect(layer->GetInputSlot(2));
+
+    // In the test_model there is only 1 Output
+    armnn::IOutputSlot& outputSlot = layer->GetOutputSlot(1);
+    delegateData.m_OutputSlotForNode[static_cast<unsigned long>(tfLiteNode->outputs->data[0])] = &outputSlot;
+    return kTfLiteOk;
+}
+
+} // namespace armnnDelegate
\ No newline at end of file