void InitDescriptors()

in src/operator/cudnn_convolution-inl.h [328:516]


  void InitDescriptors(const Context& ctx,
                       const std::vector<TShape>& in_shape,
                       const std::vector<TShape>& out_shape,
                       cudnnDataType_t cudnn_forward_compute_type,
                       cudnnDataType_t cudnn_backward_compute_type) {
    using namespace mshadow;
    size_t expected = param_.no_bias ? 2 : 3;
    CHECK_EQ(in_shape.size(), expected);
    CHECK_EQ(out_shape.size(), 1U);
    CUDNN_CALL(cudnnCreateTensorDescriptor(&in_desc_));
    CUDNN_CALL(cudnnCreateTensorDescriptor(&out_desc_));
    CUDNN_CALL(cudnnCreateTensorDescriptor(&bias_desc_));
    CUDNN_CALL(cudnnCreateFilterDescriptor(&filter_desc_));
    CUDNN_CALL(cudnnCreateConvolutionDescriptor(&forward_conv_desc_));
    CUDNN_CALL(cudnnCreateConvolutionDescriptor(&backward_conv_desc_));

    TShape dshape = in_shape[conv::kData];
    TShape wshape = in_shape[conv::kWeight];
    TShape oshape = out_shape[conv::kOut];
    TShape dstride, ostride;
    wshape[0] /= param_.num_group;
    if (param_.kernel.ndim() == 2) {
      // 2d conv

      // As of cuDNN_v6, the unsuffixed version of cudnnSetConvolution2dDescriptor()
      // requires an additional 'computeType' parameter to set the precision of the
      // convolution calculation.  This facility was available as of v5 in
      // cudnnSetConvolution2dDescriptor_v5(), but was never accessed.
      #if CUDNN_MAJOR >= 6
      CUDNN_CALL(cudnnSetConvolution2dDescriptor(forward_conv_desc_,
                                               param_.pad[0],
                                               param_.pad[1],
                                               param_.stride[0],
                                               param_.stride[1],
                                               param_.dilate[0],
                                               param_.dilate[1],
                                               CUDNN_CROSS_CORRELATION,
                                               cudnn_forward_compute_type));
      CUDNN_CALL(cudnnSetConvolution2dDescriptor(backward_conv_desc_,
                                               param_.pad[0],
                                               param_.pad[1],
                                               param_.stride[0],
                                               param_.stride[1],
                                               param_.dilate[0],
                                               param_.dilate[1],
                                               CUDNN_CROSS_CORRELATION,
                                               cudnn_backward_compute_type));
      #else
      CUDNN_CALL(cudnnSetConvolution2dDescriptor(forward_conv_desc_,
                                               param_.pad[0],
                                               param_.pad[1],
                                               param_.stride[0],
                                               param_.stride[1],
                                               param_.dilate[0],
                                               param_.dilate[1],
                                               CUDNN_CROSS_CORRELATION));
      CUDNN_CALL(cudnnSetConvolution2dDescriptor(backward_conv_desc_,
                                               param_.pad[0],
                                               param_.pad[1],
                                               param_.stride[0],
                                               param_.stride[1],
                                               param_.dilate[0],
                                               param_.dilate[1],
                                               CUDNN_CROSS_CORRELATION));
      #endif

      #if CUDNN_MAJOR >= 5
      wshape = ConvertLayout(wshape.get<4>(), param_.layout.value(), kNCHW);
      CUDNN_CALL(cudnnSetFilter4dDescriptor(filter_desc_,
                                          dtype_,
                                          format_,
                                          wshape[0],
                                          wshape[1],
                                          wshape[2],
                                          wshape[3]));
      #else
      CHECK_EQ(param_.layout.value(), kNCHW) << "CuDNN V4 only support NCHW layout";
      CUDNN_CALL(cudnnSetFilter4dDescriptor(filter_desc_,
                                          dtype_,
                                          wshape[0],
                                          wshape[1],
                                          wshape[2],
                                          wshape[3]));
      #endif

      dstride = ConvertLayout(Shape4(dshape[1] * dshape[2] * dshape[3],
                                     dshape[2] * dshape[3],
                                     dshape[3],
                                     1),
                              param_.layout.value(), kNCHW);
      dshape = ConvertLayout(dshape.get<4>(), param_.layout.value(), kNCHW);

      ostride = ConvertLayout(Shape4(oshape[1] * oshape[2] * oshape[3],
                                     oshape[2] * oshape[3],
                                     oshape[3],
                                     1),
                              param_.layout.value(), kNCHW);
      oshape = ConvertLayout(oshape.get<4>(), param_.layout.value(), kNCHW);
    } else if (param_.kernel.ndim() == 3) {
      // 3d conv
      #if CUDNN_MAJOR >= 5
      CHECK_EQ(param_.layout.value(), kNCDHW) << "CuDNN only support 3D conv with NCDHW layout";
      std::vector<int> wshape_buffer(wshape.ndim());
      CUDNN_CALL(cudnnSetFilterNdDescriptor(filter_desc_,
                                          dtype_,
                                          CUDNN_TENSOR_NCHW,
                                          static_cast<int>(wshape.ndim()),
                                          CastTShapeToIntPtr(wshape, &wshape_buffer)));
      #else
      LOG(FATAL) << "Only support CUDNN V5 for 3D convolution";
      #endif
      CUDNN_CALL(cudnnSetConvolutionNdDescriptor(forward_conv_desc_,
                                               3,
                                               param_pad_.data(),
                                               param_stride_.data(),
                                               param_dilate_.data(),
                                               CUDNN_CROSS_CORRELATION,
                                               cudnn_forward_compute_type));

      CUDNN_CALL(cudnnSetConvolutionNdDescriptor(backward_conv_desc_,
                                               3,
                                               param_pad_.data(),
                                               param_stride_.data(),
                                               param_dilate_.data(),
                                               CUDNN_CROSS_CORRELATION,
                                               cudnn_backward_compute_type));

      dstride = ConvertLayout(Shape5(dshape[1] * dshape[2] * dshape[3] * dshape[4],
                                     dshape[2] * dshape[3] * dshape[4],
                                     dshape[3] * dshape[4],
                                     dshape[4],
                                     1),
                              param_.layout.value(), kNCDHW);
      dshape = ConvertLayout(dshape.get<5>(), param_.layout.value(), kNCDHW);

      ostride = ConvertLayout(Shape5(oshape[1] * oshape[2] * oshape[3] * oshape[4],
                                     oshape[2] * oshape[3] * oshape[4],
                                     oshape[3] * oshape[4],
                                     oshape[4],
                                     1),
                              param_.layout.value(), kNCDHW);
      oshape = ConvertLayout(oshape.get<5>(), param_.layout.value(), kNCDHW);
    }
    dshape[1] /= param_.num_group;
    oshape[1] /= param_.num_group;
    weight_offset_ = wshape.Size();
    data_offset_ = dstride[1] * dshape[1];
    out_offset_ = ostride[1] * oshape[1];

    std::vector<int> dshape_buffer(dshape.ndim());
    nnvm::ShapeTypeCast(dshape.begin(), dshape.end(), dshape_buffer.data());
    std::vector<int> dstride_buffer(dstride.ndim());
    nnvm::ShapeTypeCast(dstride.begin(), dstride.end(), dstride_buffer.data());

    CUDNN_CALL(cudnnSetTensorNdDescriptor(in_desc_,
                                          dtype_,
                                          static_cast<int>(dshape.ndim()),
                                          dshape_buffer.data(),
                                          dstride_buffer.data()));

    std::vector<int> oshape_buffer(oshape.ndim());
    nnvm::ShapeTypeCast(oshape.begin(), oshape.end(), oshape_buffer.data());
    std::vector<int> ostride_buffer(ostride.ndim());
    nnvm::ShapeTypeCast(ostride.begin(), ostride.end(), ostride_buffer.data());
    CUDNN_CALL(cudnnSetTensorNdDescriptor(out_desc_,
                                          dtype_,
                                          static_cast<int>(oshape.ndim()),
                                          oshape_buffer.data(),
                                          ostride_buffer.data()));

    if (!param_.no_bias) {
      TShape bias = in_shape[conv::kBias];
      bias_offset_ = bias[0] / param_.num_group;
      std::vector<int> bias_shape = {1,
                                     static_cast<int>(bias[0] / param_.num_group),
                                     1, 1};
      std::vector<int> bias_stride = {static_cast<int>(bias_offset_), 1, 1, 1};
      if (param_.kernel.ndim() == 3) {
        bias_shape.push_back(1);
        bias_stride.push_back(1);
      }
      CUDNN_CALL(cudnnSetTensorNdDescriptor(bias_desc_,
                                          dtype_,
                                          static_cast<int>(bias_shape.size()),
                                          &bias_shape[0],
                                          &bias_stride[0]));
    }
    init_cudnn_ = true;
  }