src/backends/tosaCommon/TosaMappings.hpp

//
// Copyright © 2022 Arm Ltd and Contributors. All rights reserved.
// SPDX-License-Identifier: MIT
//

#pragma once

#include <Layer.hpp>

#include <tosa_serialization_handler.h>
#include "operatorMappings/AdditionOperator.hpp"

using namespace armnn;
using namespace tosa;

// From the input armnn::Layer, set the corresponding data field in the
// tosa::TosaSerializationTensor where constant tensor data exists in the armnn::Layer.
void SetBasicBlockConstantTensorData(Layer* layer, TosaSerializationBasicBlock* /*basicBlock*/)
{
    switch (layer->GetType())
    {
        case LayerType::Convolution2d:
        {
            // ToDo: using Convolution2d as an example as it has constant tensors for weights and bias.
            // ToDo: manually set TosaOperator data of basicBlock where constant tensors exist.
        }
        default:
            // If no switch statement for layer, no constant tensors exist in that layer, return
            return;
    }
}

// Populates a tosa::TosaSerializationBasicBlock from constructing
// tosa::TosaSerializationOperator(s) and tosa::TosaSerializationTensor(s)
// based on the input armnn::LayerType and associated armnn::TensorInfos and armnn::Descriptor.
//
// If an armnn::LayerType does not have a tosa mapping or the mapping is not implemented in ArmNN,
// an empty tosa::TosaSerializationBasicBlock() is returned with operator tosa::Op_UNKNOWN.
TosaSerializationBasicBlock* GetTosaMapping(const LayerType type,
                                            const std::vector<const TensorInfo*>& inputs,
                                            const std::vector<const TensorInfo*>& outputs,
                                            const BaseDescriptor& /*descriptor*/)
{
    switch (type)
    {
        case LayerType::Addition:
        {
            return ConvertAdditionToTosaOperator(inputs, outputs);
        }
        default:
        {
            // empty basic block when no tosa mapping implemented/exists
            TosaSerializationOperator* op = new TosaSerializationOperator(Op_UNKNOWN, Attribute_NONE, nullptr, {}, {});
            return new TosaSerializationBasicBlock("", {op}, {}, {}, {});
        }
    }
}

// Function called in armnn::OptimizeSubgraphView() when access to armnn::Layer is available
// and there is an option to set tosa basic block data from constant layer tenors available from the input layer.
TosaSerializationBasicBlock* GetTosaMappingFromLayer(Layer* layer)
{
    std::vector<const TensorInfo*> inputs;
    for (auto inputSlot : layer->GetInputSlots())
    {
        inputs.push_back(&inputSlot.GetConnection()->GetTensorInfo());
    }

    std::vector<const TensorInfo*> outputs;
    for (auto& outputSlot : layer->GetOutputSlots())
    {
        outputs.push_back(&outputSlot.GetTensorInfo());
    }

    TosaSerializationBasicBlock* basicBlock = GetTosaMapping(layer->GetType(),
                                                             inputs,
                                                             outputs,
                                                             layer->GetParameters());
    SetBasicBlockConstantTensorData(layer, basicBlock);
    return basicBlock;
}