IVGCVSW-6806 Add Unidirectional Sequence Lstm support to Neon

 * Corrected TensorInfo order for IsUnidirectionalSequenceLstmSupported
    * outputStateOut TensorInfo is not optional.
    * cellStateOut TensorInfo is not optional.
    * TensorInfo Order matches other QLSTM/LSTM layers.
 * Added missing parameters to UnidirectionalSequenceLstmOperator for
   delegate.
 * Added quantized UnidirectionalSequenceLstm support to Neon

!android-nn-driver:7457

Signed-off-by: Mike Kelly <mike.kelly@arm.com>
Change-Id: I26dde1bb96793dd25eb9081ca5ae5f63752288c4
diff --git a/src/backends/neon/workloads/NeonUnidirectionalSequenceLstmWorkload.cpp b/src/backends/neon/workloads/NeonUnidirectionalSequenceLstmWorkload.cpp
new file mode 100644
index 0000000..dfbbb3c
--- /dev/null
+++ b/src/backends/neon/workloads/NeonUnidirectionalSequenceLstmWorkload.cpp
@@ -0,0 +1,879 @@
+//
+// Copyright © 2022 Arm Ltd and Contributors. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+
+#include "NeonUnidirectionalSequenceLstmWorkload.hpp"
+#include "NeonWorkloadUtils.hpp"
+
+#include <aclCommon/ArmComputeUtils.hpp>
+#include <aclCommon/ArmComputeTensorUtils.hpp>
+
+#include <armnn/utility/NumericCast.hpp>
+#include <armnnUtils/Permute.hpp>
+#include <neon/test/NeonWorkloadFactoryHelper.hpp>
+#include <backendsCommon/WorkloadUtils.hpp>
+
+#include "neon/NeonTensorHandle.hpp"
+
+namespace
+{
+
+unsigned int CalcAclAxis(unsigned int numDimensions, unsigned int axis)
+{
+    return (numDimensions - axis) - 1;
+}
+} //namespace
+
+namespace armnn
+{
+using namespace armcomputetensorutils;
+
+NeonUnidirectionalSequenceLstmWorkload::NeonUnidirectionalSequenceLstmWorkload
+    (const UnidirectionalSequenceLstmQueueDescriptor& descriptor, const WorkloadInfo& info)
+    : NeonBaseWorkload<UnidirectionalSequenceLstmQueueDescriptor>(descriptor, info)
+{
+    // Report Profiling Details
+    ARMNN_REPORT_PROFILING_WORKLOAD_DESC("NeonUnidirectionalSequenceLstmWorkload_Construct",
+                                         descriptor.m_Parameters,
+                                         info,
+                                         GetGuid());
+
+    // Input/Output tensors
+    const arm_compute::ITensor& input         = static_cast<IAclTensorHandle*>(m_Data.m_Inputs[0])->GetTensor();
+    arm_compute::ITensor& outputStateIn       = static_cast<IAclTensorHandle*>(m_Data.m_Inputs[1])->GetTensor();
+    const arm_compute::ITensor& cellStateIn   = static_cast<IAclTensorHandle*>(m_Data.m_Inputs[2])->GetTensor();
+
+    arm_compute::ITensor& outputStateOut = static_cast<IAclTensorHandle*>(m_Data.m_Outputs[0])->GetTensor();
+    arm_compute::ITensor& cellStateOut   = static_cast<IAclTensorHandle*>(m_Data.m_Outputs[1])->GetTensor();
+    arm_compute::ITensor& output         = static_cast<IAclTensorHandle*>(m_Data.m_Outputs[2])->GetTensor();
+
+    TensorInfo inputInfo = info.m_InputTensorInfos[0];
+    TensorInfo outputInfo = info.m_OutputTensorInfos[2];
+
+    TensorShape inputLayerShape = static_cast<IAclTensorHandle*>(m_Data.m_Inputs[0])->GetShape();
+    TensorShape outputLayerShape = static_cast<IAclTensorHandle*>(m_Data.m_Outputs[2])->GetShape();
+
+    unsigned int maxTime = m_Data.m_Parameters.m_TimeMajor ? inputLayerShape[0] : inputLayerShape[1];
+    unsigned int batchSize = m_Data.m_Parameters.m_TimeMajor ? inputLayerShape[1] : inputLayerShape[0];
+    unsigned int inputSize = inputLayerShape[2];
+    unsigned int outputSize = outputLayerShape[2];
+
+    const TensorShape timeMajorShapeInput({maxTime, batchSize, inputSize});
+    const TensorShape timeMajorShapeOutput({maxTime, batchSize, outputSize});
+
+    //
+    // Permute: performed if Unidirectional Sequence Layer inputs/outputs are in batch major format.
+    //
+    if (!m_Data.m_Parameters.m_TimeMajor)
+    {
+        std::unique_ptr<arm_compute::NEPermute> layer(new arm_compute::NEPermute());
+
+        TensorInfo permuteOutInfo = inputInfo;
+        permuteOutInfo.SetShape(timeMajorShapeInput);
+        BuildArmComputeTensor(m_PermuteFirstOut, permuteOutInfo);
+        armcomputetensorutils::InitialiseArmComputeTensorEmpty(m_PermuteFirstOut);
+
+        // Permute to time major format.
+        layer->configure(&input, &m_PermuteFirstOut, arm_compute::PermutationVector(0U,2U,1U));
+        m_Permute1.reset(layer.release());
+    }
+
+    //
+    // Split and Concat Tensors
+    //
+    for (unsigned int i = 0; i < maxTime; ++i)
+    {
+        arm_compute::Tensor splitter_out;
+        arm_compute::Tensor concat_in;
+
+        auto splitterTensorInfo = inputInfo;
+        auto concatTensorInfo = outputInfo;
+        splitterTensorInfo.SetShape({batchSize, inputSize});
+        concatTensorInfo.SetShape({batchSize, outputSize});
+        BuildArmComputeTensor(splitter_out, splitterTensorInfo);
+        BuildArmComputeTensor(concat_in, concatTensorInfo);
+
+        armcomputetensorutils::InitialiseArmComputeTensorEmpty(splitter_out);
+        armcomputetensorutils::InitialiseArmComputeTensorEmpty(concat_in);
+
+        // append to std::vector<arm_compute::Tensor>
+        m_SplitterOutputsTensors.push_back(std::move(splitter_out));
+        m_ConcatInputsTensors.push_back(std::move(concat_in));
+    }
+
+    for (unsigned int i = 0; i < maxTime; ++i)
+    {
+        // append to std::vector<arm_compute::ITensor*>
+        m_SplitterOutputs.push_back(&m_SplitterOutputsTensors[i]);
+        m_ConcatInputs.push_back(&m_ConcatInputsTensors[i]);
+    }
+
+    //
+    // Split
+    //
+    unsigned int numberDimensions = 3;
+    unsigned int dimension = 0; // splitting on 0-dimension (i.e. maxTime dimension)
+
+    if (maxTime != 1) // ACL split does not work with only one element to split.
+    {
+        ViewsDescriptor splitterDesc(maxTime, numberDimensions);
+        unsigned int splitterDimSizes[3] = {1, batchSize, inputSize};
+        for (unsigned int outputIdx = 0u; outputIdx < maxTime; ++outputIdx)
+        {
+            splitterDesc.SetViewOriginCoord(outputIdx, dimension, splitterDimSizes[dimension] * outputIdx);
+            for (unsigned int dimIdx = 0u; dimIdx < numberDimensions; ++dimIdx)
+            {
+                splitterDesc.SetViewSize(outputIdx, dimIdx, splitterDimSizes[dimIdx]);
+            }
+        }
+
+        std::set<unsigned int> splitAxis = ComputeSplitAxis(splitterDesc, timeMajorShapeInput);
+
+        std::unique_ptr<arm_compute::NESplit> split_layer(new arm_compute::NESplit());
+        unsigned int                          aclAxisSplit = CalcAclAxis(splitterDesc.GetNumDimensions(),
+                                                                         *splitAxis.begin());
+        if (!m_Data.m_Parameters.m_TimeMajor)
+        {
+            split_layer->configure(&m_PermuteFirstOut, m_SplitterOutputs, aclAxisSplit);
+        } else
+        {
+            split_layer->configure(&input, m_SplitterOutputs, aclAxisSplit);
+        }
+
+        split_layer->prepare();
+        m_Splitter.reset(split_layer.release());
+    }
+
+    //
+    // Lstm
+    //
+    arm_compute::LSTMParams<arm_compute::ITensor> lstm_param;
+
+    lstm_param.set_cell_clip_params(descriptor.m_Parameters.m_ClippingThresCell);
+    lstm_param.set_projection_clip_params(descriptor.m_Parameters.m_ClippingThresProj);
+
+    lstm_param.set_matmul_scale_params(descriptor.m_Parameters.m_InputIntermediateScale,
+                                       descriptor.m_Parameters.m_ForgetIntermediateScale,
+                                       descriptor.m_Parameters.m_CellIntermediateScale,
+                                       descriptor.m_Parameters.m_OutputIntermediateScale);
+
+    lstm_param.set_hidden_state_params(descriptor.m_Parameters.m_HiddenStateZeroPoint,
+                                       descriptor.m_Parameters.m_HiddenStateScale);
+
+    m_InputToForgetWeightsTensor = std::make_unique<arm_compute::Tensor>();
+    BuildArmComputeTensor(*m_InputToForgetWeightsTensor, m_Data.m_InputToForgetWeights->GetTensorInfo());
+
+    m_InputToCellWeightsTensor = std::make_unique<arm_compute::Tensor>();
+    BuildArmComputeTensor(*m_InputToCellWeightsTensor, m_Data.m_InputToCellWeights->GetTensorInfo());
+
+    m_InputToOutputWeightsTensor = std::make_unique<arm_compute::Tensor>();
+    BuildArmComputeTensor(*m_InputToOutputWeightsTensor, m_Data.m_InputToOutputWeights->GetTensorInfo());
+
+    m_RecurrentToForgetWeightsTensor = std::make_unique<arm_compute::Tensor>();
+    BuildArmComputeTensor(*m_RecurrentToForgetWeightsTensor, m_Data.m_RecurrentToForgetWeights->GetTensorInfo());
+
+    m_RecurrentToCellWeightsTensor = std::make_unique<arm_compute::Tensor>();
+    BuildArmComputeTensor(*m_RecurrentToCellWeightsTensor, m_Data.m_RecurrentToCellWeights->GetTensorInfo());
+
+    m_RecurrentToOutputWeightsTensor = std::make_unique<arm_compute::Tensor>();
+    BuildArmComputeTensor(*m_RecurrentToOutputWeightsTensor, m_Data.m_RecurrentToOutputWeights->GetTensorInfo());
+
+    m_ForgetGateBiasTensor = std::make_unique<arm_compute::Tensor>();
+    BuildArmComputeTensor(*m_ForgetGateBiasTensor, m_Data.m_ForgetGateBias->GetTensorInfo());
+
+    m_CellBiasTensor = std::make_unique<arm_compute::Tensor>();
+    BuildArmComputeTensor(*m_CellBiasTensor, m_Data.m_CellBias->GetTensorInfo());
+
+    m_OutputGateBiasTensor = std::make_unique<arm_compute::Tensor>();
+    BuildArmComputeTensor(*m_OutputGateBiasTensor, m_Data.m_OutputGateBias->GetTensorInfo());
+
+    // for future reference: check the AndroidNN API for the logic here
+    if (!m_Data.m_Parameters.m_CifgEnabled)
+    {
+        m_InputToInputWeightsTensor = std::make_unique<arm_compute::Tensor>();
+        BuildArmComputeTensor(*m_InputToInputWeightsTensor, m_Data.m_InputToInputWeights->GetTensorInfo());
+
+        m_RecurrentToInputWeightsTensor = std::make_unique<arm_compute::Tensor>();
+        BuildArmComputeTensor(*m_RecurrentToInputWeightsTensor, m_Data.m_RecurrentToInputWeights->GetTensorInfo());
+
+        m_CellToInputWeightsTensor = std::make_unique<arm_compute::Tensor>();
+        if (m_Data.m_CellToInputWeights != nullptr)
+        {
+            BuildArmComputeTensor(*m_CellToInputWeightsTensor, m_Data.m_CellToInputWeights->GetTensorInfo());
+        }
+
+        m_InputGateBiasTensor = std::make_unique<arm_compute::Tensor>();
+        BuildArmComputeTensor(*m_InputGateBiasTensor, m_Data.m_InputGateBias->GetTensorInfo());
+        lstm_param.set_cifg_params(m_InputToInputWeightsTensor.get(),
+                                   m_RecurrentToInputWeightsTensor.get(),
+                                   m_Data.m_CellToInputWeights ? m_CellToInputWeightsTensor.get() : nullptr,
+                                   m_InputGateBiasTensor.get());
+    }
+
+    if (m_Data.m_Parameters.m_ProjectionEnabled)
+    {
+        m_ProjectionWeightsTensor = std::make_unique<arm_compute::Tensor>();
+        BuildArmComputeTensor(*m_ProjectionWeightsTensor, m_Data.m_ProjectionWeights->GetTensorInfo());
+
+        m_ProjectionBiasTensor = std::make_unique<arm_compute::Tensor>();
+        if (m_Data.m_ProjectionBias != nullptr)
+        {
+            BuildArmComputeTensor(*m_ProjectionBiasTensor, m_Data.m_ProjectionBias->GetTensorInfo());
+        }
+
+        lstm_param.set_projection_params(m_ProjectionWeightsTensor.get(),
+                                         m_Data.m_ProjectionBias ? m_ProjectionBiasTensor.get() : nullptr);
+    }
+
+    if (m_Data.m_Parameters.m_PeepholeEnabled)
+    {
+        m_CellToForgetWeightsTensor = std::make_unique<arm_compute::Tensor>();
+        BuildArmComputeTensor(*m_CellToForgetWeightsTensor, m_Data.m_CellToForgetWeights->GetTensorInfo());
+
+        m_CellToOutputWeightsTensor = std::make_unique<arm_compute::Tensor>();
+        BuildArmComputeTensor(*m_CellToOutputWeightsTensor, m_Data.m_CellToOutputWeights->GetTensorInfo());
+
+        lstm_param.set_peephole_params(m_CellToForgetWeightsTensor.get(), m_CellToOutputWeightsTensor.get());
+    }
+
+    if (m_Data.m_Parameters.m_LayerNormEnabled)
+    {
+        m_InputLayerNormWeightsTensor = std::make_unique<arm_compute::Tensor>();
+        if (!m_Data.m_Parameters.m_CifgEnabled)
+        {
+            BuildArmComputeTensor(*m_InputLayerNormWeightsTensor, m_Data.m_InputLayerNormWeights->GetTensorInfo());
+        }
+
+        m_ForgetLayerNormWeightsTensor = std::make_unique<arm_compute::Tensor>();
+        BuildArmComputeTensor(*m_ForgetLayerNormWeightsTensor, m_Data.m_ForgetLayerNormWeights->GetTensorInfo());
+
+        m_CellLayerNormWeightsTensor = std::make_unique<arm_compute::Tensor>();
+        BuildArmComputeTensor(*m_CellLayerNormWeightsTensor, m_Data.m_CellLayerNormWeights->GetTensorInfo());
+
+        m_OutputLayerNormWeightsTensor = std::make_unique<arm_compute::Tensor>();
+        BuildArmComputeTensor(*m_OutputLayerNormWeightsTensor, m_Data.m_OutputLayerNormWeights->GetTensorInfo());
+
+        auto inputNormWeightTensor = m_Data.m_Parameters.m_CifgEnabled ? nullptr : m_InputLayerNormWeightsTensor.get();
+        lstm_param.set_layer_normalization_params(inputNormWeightTensor,
+                                                  m_ForgetLayerNormWeightsTensor.get(),
+                                                  m_CellLayerNormWeightsTensor.get(),
+                                                  m_OutputLayerNormWeightsTensor.get());
+    }
+
+    for (unsigned int i = 0; i != maxTime; ++i)
+    {
+        // Set LSTM input and output ITensors depending on:
+        // input format (timeMajor) & number of LSTM batches (maxTime).
+        arm_compute::ITensor* outputLSTM;
+        arm_compute::ITensor* inputLSTM;
+
+        // If there is only one LSTM time major batch, we will not concat OR permute.
+        // Set input of LSTM to be first input ITensor.
+        // Set output of LSTM to be final output ITensor.
+        // LSTM input/output cannot be > 2 dimensions so need to resize its TensorInfo.
+        if (maxTime == 1 && m_Data.m_Parameters.m_TimeMajor)
+        {
+            TensorShape inputShape = GetTensorShape(input.info()->tensor_shape(), 1U);
+            TensorShape outputShape = GetTensorShape(output.info()->tensor_shape(), 1U);
+
+            TensorShape inputShapeShrink({inputShape[1], inputShape[2]});
+            TensorShape outputShapeShrink({outputShape[1], outputShape[2]});
+
+            auto acl_input_shape_shrink = BuildArmComputeTensorShape(inputShapeShrink);
+            auto acl_output_shape_shrink = BuildArmComputeTensorShape(outputShapeShrink);
+
+            input.info()->set_tensor_shape(acl_input_shape_shrink);
+            inputLSTM = const_cast<arm_compute::ITensor*>(&input);
+
+            output.info()->set_tensor_shape(acl_output_shape_shrink);
+            outputLSTM = &output;
+        }
+        // If there is only one LSTM batch major batch, we will not concat, only permute.
+        // Set input of LSTM to be output of initial permute.
+        // Set output of LSTM to be first element of m_ConcatInputs & use that value later in permute.
+        // LSTM output cannot be > 2 dimensions so need to resize its TensorInfo.
+        else if (maxTime == 1 && !m_Data.m_Parameters.m_TimeMajor)
+        {
+            TensorShape inputShape = GetTensorShape(m_PermuteFirstOut.info()->tensor_shape(), 1U);
+            TensorShape inputShapeShrink({inputShape[1], inputShape[2]});
+            auto acl_input_shape_shrink = BuildArmComputeTensorShape(inputShapeShrink);
+            m_PermuteFirstOut.info()->set_tensor_shape(acl_input_shape_shrink);
+            inputLSTM = &m_PermuteFirstOut;
+
+            outputLSTM = const_cast<arm_compute::ITensor*>(m_ConcatInputs[i]);
+        }
+        // Batch major AND/OR 2+ LSTM batches so will use concat AND/OR permute later on.
+        else
+        {
+            inputLSTM = m_SplitterOutputs[i];
+            outputLSTM = const_cast<arm_compute::ITensor*>(m_ConcatInputs[i]);
+        }
+
+        std::unique_ptr<arm_compute::NEQLSTMLayer> lstm_layer(new arm_compute::NEQLSTMLayer());
+
+        lstm_layer->configure(inputLSTM,
+                              m_InputToForgetWeightsTensor.get(),
+                              m_InputToCellWeightsTensor.get(),
+                              m_InputToOutputWeightsTensor.get(),
+                              m_RecurrentToForgetWeightsTensor.get(),
+                              m_RecurrentToCellWeightsTensor.get(),
+                              m_RecurrentToOutputWeightsTensor.get(),
+                              m_ForgetGateBiasTensor.get(),
+                              m_CellBiasTensor.get(),
+                              m_OutputGateBiasTensor.get(),
+                              &cellStateIn,
+                              &outputStateIn,
+                              &cellStateOut,
+                              &outputStateOut,
+                              outputLSTM,
+                              lstm_param);
+
+        m_Layers.emplace_back(std::move(lstm_layer));
+    }
+
+    InitializeArmComputeTensorData(*m_InputToForgetWeightsTensor, m_Data.m_InputToForgetWeights);
+    InitializeArmComputeTensorData(*m_InputToCellWeightsTensor, m_Data.m_InputToCellWeights);
+    InitializeArmComputeTensorData(*m_InputToOutputWeightsTensor, m_Data.m_InputToOutputWeights);
+    InitializeArmComputeTensorData(*m_RecurrentToForgetWeightsTensor, m_Data.m_RecurrentToForgetWeights);
+    InitializeArmComputeTensorData(*m_RecurrentToCellWeightsTensor, m_Data.m_RecurrentToCellWeights);
+    InitializeArmComputeTensorData(*m_RecurrentToOutputWeightsTensor, m_Data.m_RecurrentToOutputWeights);
+    InitializeArmComputeTensorData(*m_ForgetGateBiasTensor, m_Data.m_ForgetGateBias);
+    InitializeArmComputeTensorData(*m_CellBiasTensor, m_Data.m_CellBias);
+    InitializeArmComputeTensorData(*m_OutputGateBiasTensor, m_Data.m_OutputGateBias);
+
+    if (!m_Data.m_Parameters.m_CifgEnabled)
+    {
+        InitializeArmComputeTensorData(*m_InputToInputWeightsTensor, m_Data.m_InputToInputWeights);
+        InitializeArmComputeTensorData(*m_RecurrentToInputWeightsTensor, m_Data.m_RecurrentToInputWeights);
+        if (m_Data.m_CellToInputWeights != nullptr)
+        {
+            InitializeArmComputeTensorData(*m_CellToInputWeightsTensor, m_Data.m_CellToInputWeights);
+        }
+        InitializeArmComputeTensorData(*m_InputGateBiasTensor, m_Data.m_InputGateBias);
+    }
+
+    if (m_Data.m_Parameters.m_ProjectionEnabled)
+    {
+        InitializeArmComputeTensorData(*m_ProjectionWeightsTensor, m_Data.m_ProjectionWeights);
+        if (m_Data.m_ProjectionBias != nullptr)
+        {
+            InitializeArmComputeTensorData(*m_ProjectionBiasTensor, m_Data.m_ProjectionBias);
+        }
+    }
+
+    if (m_Data.m_Parameters.m_PeepholeEnabled)
+    {
+        InitializeArmComputeTensorData(*m_CellToForgetWeightsTensor, m_Data.m_CellToForgetWeights);
+        InitializeArmComputeTensorData(*m_CellToOutputWeightsTensor, m_Data.m_CellToOutputWeights);
+    }
+
+    if (m_Data.m_Parameters.m_LayerNormEnabled)
+    {
+        if (!m_Data.m_Parameters.m_CifgEnabled)
+        {
+            InitializeArmComputeTensorData(*m_InputLayerNormWeightsTensor, m_Data.m_InputLayerNormWeights);
+        }
+        InitializeArmComputeTensorData(*m_ForgetLayerNormWeightsTensor, m_Data.m_ForgetLayerNormWeights);
+        InitializeArmComputeTensorData(*m_CellLayerNormWeightsTensor, m_Data.m_CellLayerNormWeights);
+        InitializeArmComputeTensorData(*m_OutputLayerNormWeightsTensor, m_Data.m_OutputLayerNormWeights);
+    }
+
+    // Force Compute Library to perform the necessary copying and reshaping.
+    // After which delete all the input tensors that will no longer be needed.
+    for (uint32_t i = 0; i < m_Layers.size(); ++i)
+    {
+        m_Layers[i]->prepare();
+    }
+
+    //
+    // Concat
+    //
+
+    // Expand dimensions of LSTM outputs adding one empty dimension to fit concatenate inputs.
+    TensorShape shape = GetTensorShape(m_ConcatInputs[0]->info()->tensor_shape(), 1U);
+    TensorShape shapeExpandTimeMajor({1, shape[0], shape[1]});
+    TensorShape shapeExpandBatchMajor({shape[0], 1, shape[1]});
+
+    if (maxTime != 1) // ACL concat does not work with only one element to concatenate.
+    {
+        for (unsigned int i = 0; i < maxTime; ++i)
+        {
+            m_ConcatInputs[i]->info()->set_tensor_shape(BuildArmComputeTensorShape(shapeExpandTimeMajor));
+        }
+        ConcatDescriptor  concatDescriptor(maxTime, numberDimensions);  // maxTime = num inputs (aka. number of views).
+
+        for (unsigned int inputIdx = 0u; inputIdx < maxTime; ++inputIdx)
+        {
+            concatDescriptor.SetViewOriginCoord(inputIdx, dimension, inputIdx);
+            concatDescriptor.SetConcatAxis(dimension);
+        }
+        m_Concat.reset(new arm_compute::NEConcatenateLayer());
+
+        unsigned int aclAxisConcat = CalcAclAxis(concatDescriptor.GetNumDimensions(), concatDescriptor.GetConcatAxis());
+        if (!m_Data.m_Parameters.m_TimeMajor)
+        {
+            TensorInfo concatOutputTensorInfo = outputInfo;
+            concatOutputTensorInfo.SetShape(timeMajorShapeOutput);
+            BuildArmComputeTensor(concat_out, concatOutputTensorInfo);
+            armcomputetensorutils::InitialiseArmComputeTensorEmpty(concat_out);
+
+            m_Concat->configure(m_ConcatInputs, &concat_out, aclAxisConcat);
+        }
+        else
+        {
+            m_Concat->configure(m_ConcatInputs, &output, aclAxisConcat);
+        }
+
+        m_Concat->prepare();
+    }
+    // If only one LSTM batch, we do not concat and/or permute.
+    // Must ensure final output info is expanded to correct batch major dimensions.
+    else
+    {
+        if (!m_Data.m_Parameters.m_TimeMajor)
+        {
+            output.info()->set_tensor_shape(BuildArmComputeTensorShape(shapeExpandBatchMajor));
+        }
+        else
+        {
+            output.info()->set_tensor_shape(BuildArmComputeTensorShape(shapeExpandTimeMajor));
+        }
+    }
+
+    //
+    // Permute: only done if input/output are in batch major format.
+    //
+    if (!m_Data.m_Parameters.m_TimeMajor)
+    {
+        // Output now time major. Permute output back to batch major.
+        std::unique_ptr<arm_compute::NEPermute> layer(new arm_compute::NEPermute());
+        if (maxTime != 1)
+        {
+            layer->configure(&concat_out, &output, arm_compute::PermutationVector(0U, 2U, 1U));
+        }
+        else
+        {
+            layer->configure(m_ConcatInputs[0], &output, arm_compute::PermutationVector(0U, 2U, 1U));
+        }
+        m_Permute2.reset(layer.release());
+    }
+
+    FreeUnusedTensors();
+}
+
+void NeonUnidirectionalSequenceLstmWorkload::Execute() const
+{
+    ARMNN_SCOPED_PROFILING_EVENT_NEON_GUID("NeonUnidirectionalSequenceLstmWorkload_Execute", GetGuid());
+    if (m_Permute1)
+    {
+        m_Permute1->run();
+    }
+    if (m_Splitter)
+    {
+        m_Splitter->run();
+    }
+    for (uint32_t i = 0; i < m_Layers.size(); ++i)
+    {
+        m_Layers[i]->run();
+    }
+    if (m_Concat)
+    {
+        m_Concat->run();
+    }
+    if (m_Permute2)
+    {
+        m_Permute2->run();
+    }
+}
+
+arm_compute::Status
+NeonUnidirectionalSequenceLstmWorkloadValidate(const TensorInfo& input,
+                                               const TensorInfo& outputStateIn,
+                                               const TensorInfo& cellStateIn,
+                                               const TensorInfo& outputStateOut,
+                                               const TensorInfo& cellStateOut,
+                                               const TensorInfo& output,
+                                               const UnidirectionalSequenceLstmDescriptor& descriptor,
+                                               const LstmInputParamsInfo& paramsInfo)
+{
+    TensorShape inputLayerShape = input.GetShape();
+    TensorShape outputLayerShape = output.GetShape();
+
+    unsigned int maxTime = descriptor.m_TimeMajor ? inputLayerShape[0] : inputLayerShape[1];
+    unsigned int batchSize = descriptor.m_TimeMajor ? inputLayerShape[1] : inputLayerShape[0];
+    unsigned int inputSize = inputLayerShape[2];
+    unsigned int outputSize = outputLayerShape[2];
+
+    const TensorShape timeMajorShapeInput({maxTime, batchSize, inputSize});
+    const TensorShape timeMajorShapeOutput({maxTime, batchSize, outputSize});
+
+    arm_compute::Status statusPermute1 = arm_compute::Status(arm_compute::ErrorCode::OK,
+                                                             "Permute1 status");
+    arm_compute::Status statusSplit = arm_compute::Status(arm_compute::ErrorCode::OK,
+                                                          "Split status");
+    arm_compute::Status statusLSTM = arm_compute::Status(arm_compute::ErrorCode::OK,
+                                                         "LSTM status");
+    arm_compute::Status statusConcat = arm_compute::Status(arm_compute::ErrorCode::OK,
+                                                           "Concat status");
+    arm_compute::Status statusPermute2 = arm_compute::Status(arm_compute::ErrorCode::OK,
+                                                             "Permute2 status");
+
+    const arm_compute::TensorInfo aclInputInfo  = armcomputetensorutils::BuildArmComputeTensorInfo(input);
+    const arm_compute::TensorInfo aclOutputInfo  = armcomputetensorutils::BuildArmComputeTensorInfo(output);
+
+    //
+    // Permute validate
+    //
+    TensorInfo permuteOutInfo = TensorInfo(input);
+    arm_compute::TensorInfo aclPermuteOutInfo = armcomputetensorutils::BuildArmComputeTensorInfo(permuteOutInfo);
+    if (!descriptor.m_TimeMajor)
+    {
+        statusPermute1 =  arm_compute::NEPermute::validate(&aclInputInfo,
+                                                           &aclPermuteOutInfo,
+                                                           arm_compute::PermutationVector(0U, 2U, 1U));
+    }
+
+    //
+    // Split and Concat Tensors validate
+    //
+    std::vector<arm_compute::TensorInfo> splitterOutputsTensorInfos;
+    std::vector<arm_compute::TensorInfo> concatInputsTensorInfos;
+    std::vector<arm_compute::ITensorInfo*> splitterOutputsTensorInfosPtr;
+    std::vector<const arm_compute::ITensorInfo*> concatInputsTensorInfosPtr;
+    splitterOutputsTensorInfos.reserve(maxTime);
+    concatInputsTensorInfos.reserve(maxTime);
+    for (unsigned int i = 0; i < maxTime; ++i)
+    {
+        arm_compute::TensorInfo splitter_out;
+        arm_compute::TensorInfo concat_in;
+
+        auto splitterTensorInfo = TensorInfo(input);
+        auto concatTensorInfo   = TensorInfo(output);
+        splitterTensorInfo.SetShape({batchSize, inputSize});
+        concatTensorInfo.SetShape({batchSize, outputSize});
+
+        arm_compute::TensorInfo aclSplitterTensorInfo
+            = armcomputetensorutils::BuildArmComputeTensorInfo(splitterTensorInfo);
+        arm_compute::TensorInfo aclConcatTensorInfo
+            = armcomputetensorutils::BuildArmComputeTensorInfo(concatTensorInfo);
+
+        splitterOutputsTensorInfos.emplace_back(aclSplitterTensorInfo);
+        concatInputsTensorInfos.emplace_back(aclConcatTensorInfo);
+        splitterOutputsTensorInfosPtr.emplace_back(&splitterOutputsTensorInfos[i]);
+        concatInputsTensorInfosPtr.emplace_back(&concatInputsTensorInfos[i]);
+    }
+
+    //
+    // Split validate
+    //
+    unsigned int numberDimensions = 3;
+    unsigned int dimension = 0; // splitting on 0-dimension (i.e. maxTime dimension)
+    unsigned int aclAxisSplit = CalcAclAxis(numberDimensions, dimension);
+
+    if (maxTime != 1) // ACL split does not work with only one element to split.
+    {
+        if (!descriptor.m_TimeMajor)
+        {
+            statusSplit = arm_compute::NESplit::validate(&aclPermuteOutInfo,
+                                                         splitterOutputsTensorInfosPtr,
+                                                         aclAxisSplit);
+        } else
+        {
+            statusSplit = arm_compute::NESplit::validate(&aclInputInfo, splitterOutputsTensorInfosPtr, aclAxisSplit);
+        }
+    }
+
+    //
+    // LSTM validate
+    //
+
+    arm_compute::LSTMParams<arm_compute::ITensorInfo> lstm_params_info;
+
+    const TensorInfo& scratchBuffer = TensorInfo(cellStateIn.GetShape(), input.GetDataType());
+
+    lstm_params_info.set_cell_clip_params(descriptor.m_ClippingThresCell);
+    lstm_params_info.set_projection_clip_params(descriptor.m_ClippingThresProj);
+    // The inputs and outputs
+    const arm_compute::TensorInfo aclOutputStateInInfo = BuildArmComputeTensorInfo(outputStateIn);
+    const arm_compute::TensorInfo aclCellStateInInfo = BuildArmComputeTensorInfo(cellStateIn);
+    const arm_compute::TensorInfo aclScratchBufferInfo = BuildArmComputeTensorInfo(scratchBuffer);
+    const arm_compute::TensorInfo aclOutputStateOutInfo = BuildArmComputeTensorInfo(outputStateOut);
+    const arm_compute::TensorInfo aclCellStateOutInfo = BuildArmComputeTensorInfo(cellStateOut);
+
+    // Basic parameters
+    const arm_compute::TensorInfo aclInputToForgetWeightsInfo
+                                      = BuildArmComputeTensorInfo(paramsInfo.GetInputToForgetWeights());
+    const arm_compute::TensorInfo aclInputToCellWeightsInfo
+                                      = BuildArmComputeTensorInfo(paramsInfo.GetInputToCellWeights());
+    const arm_compute::TensorInfo aclInputToOutputWeightsInfo
+                                      = BuildArmComputeTensorInfo(paramsInfo.GetInputToOutputWeights());
+    const arm_compute::TensorInfo aclRecurrentToForgetWeightsInfo
+                                      = BuildArmComputeTensorInfo(paramsInfo.GetRecurrentToForgetWeights());
+    const arm_compute::TensorInfo aclRecurrentToCellWeightsInfo
+                                      = BuildArmComputeTensorInfo(paramsInfo.GetRecurrentToCellWeights());
+    const arm_compute::TensorInfo aclRecurrentToOutputWeightsInfo
+                                      = BuildArmComputeTensorInfo(paramsInfo.GetRecurrentToOutputWeights());
+    const arm_compute::TensorInfo aclForgetGateBiasInfo
+                                      = BuildArmComputeTensorInfo(paramsInfo.GetForgetGateBias());
+    const arm_compute::TensorInfo aclCellBiasInfo
+                                      = BuildArmComputeTensorInfo(paramsInfo.GetCellBias());
+    const arm_compute::TensorInfo aclOutputGateBiasInfo
+                                      = BuildArmComputeTensorInfo(paramsInfo.GetOutputGateBias());
+
+    arm_compute::TensorInfo aclInputToInputWeightsInfo;
+    arm_compute::TensorInfo aclRecurrentToInputWeightsInfo;
+    arm_compute::TensorInfo aclCellToInputWeightsInfo;
+    arm_compute::TensorInfo aclInputGateBiasInfo;
+    arm_compute::TensorInfo aclProjectionWeightsInfo;
+    arm_compute::TensorInfo aclProjectionBiasInfo;
+    arm_compute::TensorInfo aclCellToForgetWeightsInfo;
+    arm_compute::TensorInfo aclCellToOutputWeightsInfo;
+
+    arm_compute::TensorInfo aclInputLayerNormWeightsInfo;
+    arm_compute::TensorInfo aclForgetLayerNormWeightsInfo;
+    arm_compute::TensorInfo aclCellLayerNormWeightsInfo;
+    arm_compute::TensorInfo aclOutputLayerNormWeightsInfo;
+
+    if (!descriptor.m_CifgEnabled)
+    {
+        if (descriptor.m_PeepholeEnabled)
+        {
+            aclCellToInputWeightsInfo = BuildArmComputeTensorInfo(paramsInfo.GetCellToInputWeights());
+        }
+        aclInputToInputWeightsInfo = BuildArmComputeTensorInfo(paramsInfo.GetInputToInputWeights());
+        aclRecurrentToInputWeightsInfo = BuildArmComputeTensorInfo(paramsInfo.GetRecurrentToInputWeights());
+        aclInputGateBiasInfo = BuildArmComputeTensorInfo(paramsInfo.GetInputGateBias());
+
+        lstm_params_info.set_cifg_params(&aclInputToInputWeightsInfo,
+                                         &aclRecurrentToInputWeightsInfo,
+                                         descriptor.m_PeepholeEnabled ? &aclCellToInputWeightsInfo : nullptr,
+                                         &aclInputGateBiasInfo);
+    }
+
+    if (descriptor.m_ProjectionEnabled)
+    {
+        if (paramsInfo.m_ProjectionBias != nullptr)
+        {
+            aclProjectionBiasInfo = BuildArmComputeTensorInfo(paramsInfo.GetProjectionBias());
+        }
+        aclProjectionWeightsInfo = BuildArmComputeTensorInfo(paramsInfo.GetProjectionWeights());
+
+        lstm_params_info.set_projection_params(&aclProjectionWeightsInfo,
+                                               paramsInfo.m_ProjectionBias ? &aclProjectionBiasInfo : nullptr);
+    }
+
+    if (descriptor.m_PeepholeEnabled)
+    {
+        aclCellToForgetWeightsInfo = BuildArmComputeTensorInfo(paramsInfo.GetCellToForgetWeights());
+        aclCellToOutputWeightsInfo = BuildArmComputeTensorInfo(paramsInfo.GetCellToOutputWeights());
+
+        lstm_params_info.set_peephole_params(&aclCellToForgetWeightsInfo, &aclCellToOutputWeightsInfo);
+    }
+
+    if (descriptor.m_LayerNormEnabled)
+    {
+        if (!descriptor.m_CifgEnabled)
+        {
+            aclInputLayerNormWeightsInfo = BuildArmComputeTensorInfo(paramsInfo.GetInputLayerNormWeights());
+        }
+        aclForgetLayerNormWeightsInfo = BuildArmComputeTensorInfo(paramsInfo.GetForgetLayerNormWeights());
+        aclCellLayerNormWeightsInfo = BuildArmComputeTensorInfo(paramsInfo.GetCellLayerNormWeights());
+        aclOutputLayerNormWeightsInfo = BuildArmComputeTensorInfo(paramsInfo.GetOutputLayerNormWeights());
+
+        lstm_params_info.set_layer_normalization_params(descriptor.m_CifgEnabled ? nullptr :
+                                                        &aclInputLayerNormWeightsInfo,
+                                                        &aclForgetLayerNormWeightsInfo,
+                                                        &aclCellLayerNormWeightsInfo,
+                                                        &aclOutputLayerNormWeightsInfo);
+    }
+
+    lstm_params_info.set_matmul_scale_params(descriptor.m_InputIntermediateScale,
+                                             descriptor.m_ForgetIntermediateScale,
+                                             descriptor.m_CellIntermediateScale,
+                                             descriptor.m_OutputIntermediateScale);
+
+    lstm_params_info.set_hidden_state_params(descriptor.m_HiddenStateZeroPoint, descriptor.m_HiddenStateScale);
+
+    for (unsigned int i = 0; i != maxTime; ++i)
+    {
+
+        // Set LSTM input and output ITensors depending on:
+        // input format (timeMajor) & number of LSTM batches (maxTime).
+        arm_compute::ITensorInfo* outputLSTM;
+        arm_compute::ITensorInfo* inputLSTM;
+
+        // If there is only one LSTM time major batch, we will not concat OR permute.
+        // Set input of LSTM to be first input ITensor.
+        // Set output of LSTM to be final output ITensor.
+        // LSTM input/output cannot be > 2 dimensions so need to resize its TensorInfo.
+        if (maxTime == 1 && !descriptor.m_TimeMajor)
+        {
+            TensorShape inputShape = GetTensorShape(aclInputInfo.tensor_shape(), 1U);
+            TensorShape outputShape = GetTensorShape(aclOutputInfo.tensor_shape(), 1U);
+
+            TensorShape inputShapeShrink({inputShape[1], inputShape[2]});
+            TensorShape outputShapeShrink({outputShape[1], outputShape[2]});
+
+            auto acl_input_shape_shrink = BuildArmComputeTensorShape(inputShapeShrink);
+            auto acl_output_shape_shrink = BuildArmComputeTensorShape(outputShapeShrink);
+
+            const_cast<arm_compute::TensorInfo*>(&aclInputInfo)->set_tensor_shape(acl_input_shape_shrink);
+            inputLSTM = const_cast<arm_compute::TensorInfo*>(&aclInputInfo);
+
+            const_cast<arm_compute::TensorInfo*>(&aclOutputInfo)->set_tensor_shape(acl_output_shape_shrink);
+            outputLSTM = const_cast<arm_compute::TensorInfo*>(&aclOutputInfo);
+        }
+        // If there is only one LSTM batch major batch, we will not concat, only permute.
+        // Set input of LSTM to be output of initial permute.
+        // Set output of LSTM to be first element of m_ConcatInputs & use that value later in permute.
+        // LSTM output cannot be > 2 dimensions so need to resize its TensorInfo.
+        else if (maxTime == 1 && !descriptor.m_TimeMajor)
+        {
+            TensorShape inputShape = GetTensorShape(aclPermuteOutInfo.tensor_shape(), 1U);
+            TensorShape inputShapeShrink({inputShape[1], inputShape[2]});
+            auto acl_input_shape_shrink = BuildArmComputeTensorShape(inputShapeShrink);
+            aclPermuteOutInfo.set_tensor_shape(acl_input_shape_shrink);
+            inputLSTM = &aclPermuteOutInfo;
+
+            outputLSTM = const_cast<arm_compute::ITensorInfo*>(concatInputsTensorInfosPtr[i]);
+        }
+        // Batch major AND/OR 2+ LSTM batches so will use concat AND/OR permute later on.
+        else
+        {
+            inputLSTM = splitterOutputsTensorInfosPtr[i];
+            outputLSTM = const_cast<arm_compute::ITensorInfo*>(concatInputsTensorInfosPtr[i]);
+        }
+
+        statusLSTM = arm_compute::NEQLSTMLayer::validate(inputLSTM,
+                                                         &aclInputToForgetWeightsInfo,
+                                                         &aclInputToCellWeightsInfo,
+                                                         &aclInputToOutputWeightsInfo,
+                                                         &aclRecurrentToForgetWeightsInfo,
+                                                         &aclRecurrentToCellWeightsInfo,
+                                                         &aclRecurrentToOutputWeightsInfo,
+                                                         &aclForgetGateBiasInfo,
+                                                         &aclCellBiasInfo,
+                                                         &aclOutputGateBiasInfo,
+                                                         &aclCellStateInInfo,
+                                                         &aclOutputStateInInfo,
+                                                         &aclCellStateOutInfo,
+                                                         &aclOutputStateOutInfo,
+                                                         outputLSTM,
+                                                         lstm_params_info);
+    }
+
+    //
+    // Concat validate
+    //
+
+    // Expand dimensions of LSTM outputs adding one empty dimension to fit concatenate inputs.
+    TensorShape shape = GetTensorShape(concatInputsTensorInfosPtr[0]->tensor_shape(), 1U);
+    TensorShape shapeExpandTimeMajor({1, shape[0], shape[1]});
+    TensorShape shapeExpandBatchMajor({shape[0], 1, shape[1]});
+
+    TensorInfo concatOutputTensorInfo = TensorInfo(output);
+    concatOutputTensorInfo.SetShape(timeMajorShapeOutput);
+    arm_compute::TensorInfo aclConcatOutputTensorInfo= BuildArmComputeTensorInfo(concatOutputTensorInfo);
+
+    if (maxTime != 1) // ACL concat does not work with only one element to concatenate.
+    {
+        for (unsigned int i = 0; i < maxTime; ++i)
+        {
+            auto acl_shape_expand = BuildArmComputeTensorShape(shapeExpandTimeMajor);
+            concatInputsTensorInfos[i].set_tensor_shape(acl_shape_expand);
+        }
+
+        unsigned int aclAxisConcat = CalcAclAxis(numberDimensions, dimension);
+        if (!descriptor.m_TimeMajor)
+        {
+            statusConcat = arm_compute::NEConcatenateLayer::validate(concatInputsTensorInfosPtr,
+                                                                     &aclConcatOutputTensorInfo,
+                                                                     aclAxisConcat);
+        }
+        else
+        {
+            statusConcat = arm_compute::NEConcatenateLayer::validate(concatInputsTensorInfosPtr,
+                                                                     &aclOutputInfo,
+                                                                     aclAxisConcat);
+        }
+    }
+    // If only one LSTM batch, we do not concat and/or permute.
+    // Must ensure final output info is expanded to correct batch major dimensions.
+    else
+    {
+        if (!descriptor.m_TimeMajor)
+        {
+            const_cast<arm_compute::TensorInfo*>(&aclInputInfo)->set_tensor_shape(
+                BuildArmComputeTensorShape(shapeExpandBatchMajor));
+        }
+        else
+        {
+            const_cast<arm_compute::TensorInfo*>(&aclInputInfo)->set_tensor_shape(
+                BuildArmComputeTensorShape(shapeExpandTimeMajor));
+        }
+    }
+
+    //
+    // Permute validate
+    //
+    if (!descriptor.m_TimeMajor)
+    {
+        // Output now time major. Permute output back to batch major.
+        if (maxTime != 1)
+        {
+            statusPermute2 = arm_compute::NEPermute::validate(&aclConcatOutputTensorInfo,
+                                                              &aclOutputInfo,
+                                                              arm_compute::PermutationVector(0U, 2U, 1U));
+        }
+        else
+        {
+            statusPermute2 = arm_compute::NEPermute::validate(concatInputsTensorInfosPtr[0],
+                                                              &aclOutputInfo,
+                                                              arm_compute::PermutationVector(0U, 2U, 1U));
+        }
+    }
+
+    auto okCode = arm_compute::ErrorCode::OK;
+    if (statusPermute1.error_code() == okCode &&
+        statusSplit.error_code()    == okCode &&
+        statusLSTM .error_code()    == okCode &&
+        statusConcat.error_code()   == okCode &&
+        statusPermute2.error_code() == okCode)
+    {
+        return arm_compute::Status(arm_compute::ErrorCode::OK,
+                                   "All Unidirectional Sequence LSTM layer validate status OK.");
+    }
+    else
+    {
+        return arm_compute::Status(arm_compute::ErrorCode::RUNTIME_ERROR,
+                                   "Unidirectional Sequence LSTM layer validate status failed.");
+    }
+}
+
+void NeonUnidirectionalSequenceLstmWorkload::FreeUnusedTensors()
+{
+    FreeTensorIfUnused(m_InputToInputWeightsTensor);
+    FreeTensorIfUnused(m_InputToForgetWeightsTensor);
+    FreeTensorIfUnused(m_InputToCellWeightsTensor);
+    FreeTensorIfUnused(m_InputToOutputWeightsTensor);
+    FreeTensorIfUnused(m_RecurrentToInputWeightsTensor);
+    FreeTensorIfUnused(m_RecurrentToForgetWeightsTensor);
+    FreeTensorIfUnused(m_RecurrentToCellWeightsTensor);
+    FreeTensorIfUnused(m_RecurrentToOutputWeightsTensor);
+    FreeTensorIfUnused(m_CellToInputWeightsTensor);
+    FreeTensorIfUnused(m_CellToForgetWeightsTensor);
+    FreeTensorIfUnused(m_CellToOutputWeightsTensor);
+    FreeTensorIfUnused(m_InputGateBiasTensor);
+    FreeTensorIfUnused(m_ForgetGateBiasTensor);
+    FreeTensorIfUnused(m_CellBiasTensor);
+    FreeTensorIfUnused(m_OutputGateBiasTensor);
+    FreeTensorIfUnused(m_ProjectionWeightsTensor);
+    FreeTensorIfUnused(m_ProjectionBiasTensor);
+    FreeTensorIfUnused(m_InputLayerNormWeightsTensor);
+    FreeTensorIfUnused(m_ForgetLayerNormWeightsTensor);
+    FreeTensorIfUnused(m_CellLayerNormWeightsTensor);
+    FreeTensorIfUnused(m_OutputLayerNormWeightsTensor);
+}
+
+} //namespace armnn