MNN/source/shape/ShapeTopKV2.cpp

//
//  ShapeTopKV2.cpp
//  MNN
//
//  Created by MNN on 2019/01/10.
//  Copyright © 2018, Alibaba Group Holding Limited
//

#include "shape/SizeComputer.hpp"
#include "core/Macro.h"

namespace MNN {

class TopKV2SizeComputer : public SizeComputer {
    virtual bool onComputeSize(const MNN::Op* op, const std::vector<Tensor*>& inputs,
                               const std::vector<Tensor*>& outputs) const override {
        MNN_ASSERT(2 == inputs.size() || 3 == inputs.size());
        MNN_ASSERT(2 == outputs.size());
        auto input   = inputs[0];
        auto kTensor = inputs[1];
        MNN_ASSERT(kTensor->elementSize() == 1); // Scalar
        MNN_ASSERT(kTensor->getType().code == halide_type_int);
        const int k              = kTensor->host<int32_t>()[0];
        const int inputDimension = input->buffer().dimensions;
        int axis = (inputs.size() == 3 ? inputs[2]->host<int32_t>()[0] : inputDimension - 1);
        if (axis < 0) axis += input->dimensions();
        // outputs: 0 --> data, 1 --> index

        auto outputData                 = outputs[0];
        outputData->buffer().dimensions = inputDimension;
        memcpy(outputData->buffer().dim, input->buffer().dim, inputDimension * sizeof(halide_dimension_t));
        outputData->buffer().dim[axis].extent = k;
        outputData->buffer().type                           = input->buffer().type;

        auto outputIndices                 = outputs[1];
        outputIndices->buffer().dimensions = inputDimension;
        memcpy(outputIndices->buffer().dim, input->buffer().dim, inputDimension * sizeof(halide_dimension_t));
        outputIndices->buffer().dim[axis].extent = k;
        outputIndices->setType(MNN::DataType_DT_INT32);
        TensorUtils::getDescribe(outputs[0])->dimensionFormat = TensorUtils::getDescribe(inputs[0])->dimensionFormat;
        TensorUtils::getDescribe(outputs[1])->dimensionFormat = TensorUtils::getDescribe(inputs[1])->dimensionFormat;

        return true;
    }
};

REGISTER_SHAPE_INPUTS(TopKV2SizeComputer, OpType_TopKV2, (std::vector<int>{1,2}));
} // namespace MNN