Utils.h

Go to the documentation of this file.

/*
 * Copyright (c) 2020 Samsung Electronics Co., Ltd. All Rights Reserved
 * Copyright 2018 The TensorFlow Authors. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 
#ifndef __NNFW_RUY_UTILS_H__
#define __NNFW_RUY_UTILS_H__
 
#include "Types.h"
#include "Shape.h"
 
#include <stdexcept>
 
namespace nnfw
{
namespace ruy
{
template <typename T>
inline void ExtractPatchIntoBufferColumn(const Shape &input_shape, int w, int h, int b, int kheight,
                                         int kwidth, int stride_width, int stride_height,
                                         int pad_width, int pad_height, int in_width, int in_height,
                                         int in_depth, int single_buffer_length, int buffer_id,
                                         const T *in_data, T *conv_buffer_data, uint8_t zero_byte)
{
  assert(input_shape.DimensionsCount() == 4);
  // This chunk of code reshapes all the inputs corresponding to
  // output (b, h, w) to a column vector in conv_buffer(:, buffer_id).
  const int kwidth_times_indepth = kwidth * in_depth;
  const int inwidth_times_indepth = in_width * in_depth;
  const int ih_ungated_start = h * stride_height - pad_height;
  const int ih_ungated_end = (ih_ungated_start + kheight);
  const int ih_end = std::min(ih_ungated_end, in_height);
  const int iw_ungated_start = w * stride_width - pad_width;
  const int iw_ungated_end = (iw_ungated_start + kwidth);
  const int iw_end = std::min(iw_ungated_end, in_width);
  // If the patch is off the edge of the input image, skip writing those rows
  // and columns from the patch into the output array.
  const int h_offset = std::max(0, -ih_ungated_start);
  const int w_offset = std::max(0, -iw_ungated_start);
  const int ih_start = std::max(0, ih_ungated_start);
  const int iw_start = std::max(0, iw_ungated_start);
  const int single_row_num = std::min(kwidth - w_offset, in_width - iw_start) * in_depth;
  const int output_row_offset = (buffer_id * single_buffer_length);
  int out_offset = output_row_offset + (h_offset * kwidth + w_offset) * in_depth;
  int in_offset = Offset(input_shape, b, ih_start, iw_start, 0);
 
  // Express all of the calculations as padding around the input patch.
  const int top_padding = h_offset;
  const int bottom_padding = (ih_ungated_end - ih_end);
  const int left_padding = w_offset;
  const int right_padding = (iw_ungated_end - iw_end);
  assert(single_row_num == ((kwidth - (left_padding + right_padding)) * in_depth));
 
  // Write out zeroes to the elements representing the top rows of the input
  // patch that are off the edge of the input image.
  if (top_padding > 0)
  {
    const int top_row_elements = (top_padding * kwidth * in_depth);
    memset(conv_buffer_data + output_row_offset, zero_byte, (top_row_elements * sizeof(T)));
  }
 
  // If the patch is on the interior of the input image horizontally, just copy
  // over the rows sequentially, otherwise add zero padding at the start or end.
  if ((left_padding == 0) && (right_padding == 0))
  {
    for (int ih = ih_start; ih < ih_end; ++ih)
    {
      memcpy(conv_buffer_data + out_offset, in_data + in_offset, single_row_num * sizeof(T));
      out_offset += kwidth_times_indepth;
      in_offset += inwidth_times_indepth;
    }
  }
  else
  {
    for (int ih = ih_start; ih < ih_end; ++ih)
    {
      if (left_padding > 0)
      {
        const int left_start = (out_offset - (left_padding * in_depth));
        memset(conv_buffer_data + left_start, zero_byte, (left_padding * in_depth * sizeof(T)));
      }
      memcpy(conv_buffer_data + out_offset, in_data + in_offset, single_row_num * sizeof(T));
      if (right_padding > 0)
      {
        const int right_start = (out_offset + single_row_num);
        memset(conv_buffer_data + right_start, zero_byte, (right_padding * in_depth * sizeof(T)));
      }
      out_offset += kwidth_times_indepth;
      in_offset += inwidth_times_indepth;
    }
  }
 
  // If the bottom of the patch falls off the input image, pad the values
  // representing those input rows with zeroes.
  if (bottom_padding > 0)
  {
    const int bottom_row_elements = (bottom_padding * kwidth * in_depth);
    const int bottom_start =
      output_row_offset + ((top_padding + (ih_end - ih_start)) * kwidth * in_depth);
    memset(conv_buffer_data + bottom_start, zero_byte, (bottom_row_elements * sizeof(T)));
  }
}
 
// Supports per-batch zero_byte for per-batch asymmetric quantized inputs.
template <typename T>
void DilatedIm2col(const ConvParams &params, const Shape &input_shape, const T *input_data,
                   const Shape &filter_shape, const Shape &output_shape, T *im2col_data,
                   const int32_t *zero_bytes, const int zero_bytes_len)
{
  const int stride_width = params.stride_width;
  const int stride_height = params.stride_height;
  const int dilation_width_factor = params.dilation_width_factor;
  const int dilation_height_factor = params.dilation_height_factor;
  const int pad_width = params.padding_values.width;
  const int pad_height = params.padding_values.height;
  assert(input_shape.DimensionsCount() == 4);
  assert(filter_shape.DimensionsCount() == 4);
  assert(output_shape.DimensionsCount() == 4);
 
  // For dilated convolution, the input pixels are not contiguous therefore we
  // can't use the same optimizations as Im2Col(). Though note this code would
  // work fine for the non-dilated case too (though likely a bit slower).
  assert(dilation_width_factor != 1 || dilation_height_factor != 1);
  assert(im2col_data);
  const int batches = MatchingDim(input_shape, 0, output_shape, 0);
  const int input_height = input_shape.Dims(1);
  const int input_width = input_shape.Dims(2);
  const int input_depth = MatchingDim(input_shape, 3, filter_shape, 3);
  const int filter_height = filter_shape.Dims(1);
  const int filter_width = filter_shape.Dims(2);
  const int output_height = output_shape.Dims(1);
  const int output_width = output_shape.Dims(2);
  MatchingDim(output_shape, 3, filter_shape, 0);
 
  // Construct the MxN sized im2col matrix.
  // The rows M, are sub-ordered B x H x W
  const Shape row_shape({1, batches, output_height, output_width});
  // The columns, N, are sub-ordered Kh x Kw x Din
  const Shape col_shape({1, filter_height, filter_width, input_depth});
  // Use dimensions M and N to construct dims for indexing directly into im2col
  const Shape im2col_shape({1, 1, row_shape.FlatSize(), col_shape.FlatSize()});
 
  // Loop through the output rows (B x H x W)
  for (int batch = 0; batch < batches; ++batch)
  {
    const T zero_byte =
      zero_bytes_len > 1 ? static_cast<T>(zero_bytes[batch]) : static_cast<T>(zero_bytes[0]);
    for (int out_y = 0; out_y < output_height; ++out_y)
    {
      for (int out_x = 0; out_x < output_width; ++out_x)
      {
        // Each im2col row is an output pixel. Arrange the input data in this
        // row in an order we can conveniently multiply with the filter data.
        int row_offset = Offset(row_shape, 0, batch, out_y, out_x);
        const int in_x_origin = (out_x * stride_width) - pad_width;
        const int in_y_origin = (out_y * stride_height) - pad_height;
        // Loop through all the pixels of the filter (Kh x Kw)
        for (int filter_y = 0; filter_y < filter_height; ++filter_y)
        {
          const int in_y = in_y_origin + dilation_height_factor * filter_y;
          if ((in_y >= 0) && (in_y < input_height))
          {
            // Filter row is within the input data.
            // Loop through all the filter pixels in this row.
            for (int filter_x = 0; filter_x < filter_width; ++filter_x)
            {
              const int in_x = in_x_origin + dilation_width_factor * filter_x;
              int col_offset = Offset(col_shape, 0, filter_y, filter_x, 0);
              T *dst = im2col_data + Offset(im2col_shape, 0, 0, row_offset, col_offset);
              if ((in_x >= 0) && (in_x < input_width))
              {
                // Filter pixel is within the input, copy the input data.
                T const *src = input_data + Offset(input_shape, batch, in_y, in_x, 0);
                memcpy(dst, src, input_depth * sizeof(T));
              }
              else
              {
                // Filter pixel is outside the input, zero it out.
                memset(dst, zero_byte, input_depth * sizeof(T));
              }
            }
          }
          else
          {
            // Filter row is outside the input, zero out the entire filter row.
            int col_offset = Offset(col_shape, 0, filter_y, 0, 0);
            T *dst = im2col_data + Offset(im2col_shape, 0, 0, row_offset, col_offset);
            memset(dst, zero_byte, filter_width * input_depth * sizeof(T));
          }
        }
      }
    }
  }
}
 
template <typename T>
void DilatedIm2col(const ConvParams &params, uint8_t zero_byte, const Shape &input_shape,
                   const T *input_data, const Shape &filter_shape, const Shape &output_shape,
                   T *im2col_data)
{
  const int32_t zero_point = static_cast<int32_t>(zero_byte);
  DilatedIm2col<T>(params, input_shape, input_data, filter_shape, output_shape, im2col_data,
                   &zero_point, 1);
}
 
template <typename T>
void Im2col(const ConvParams &params, int kheight, int kwidth, uint8_t zero_byte,
            const Shape &input_shape, const T *input_data, const Shape &output_shape,
            T *output_data)
{
  const int stride_width = params.stride_width;
  const int stride_height = params.stride_height;
  const int pad_width = params.padding_values.width;
  const int pad_height = params.padding_values.height;
  assert(input_shape.DimensionsCount() == 4);
  assert(output_shape.DimensionsCount() == 4);
 
  const int batches = MatchingDim(input_shape, 0, output_shape, 0);
  const int input_depth = input_shape.Dims(3);
  const int input_width = input_shape.Dims(2);
  const int input_height = input_shape.Dims(1);
  const int output_depth = output_shape.Dims(3);
  const int output_width = output_shape.Dims(2);
  const int output_height = output_shape.Dims(1);
 
  int buffer_id = 0;
  // Loop over the output nodes.
  for (int b = 0; b < batches; ++b)
  {
    for (int h = 0; h < output_height; ++h)
    {
      for (int w = 0; w < output_width; ++w)
      {
        ExtractPatchIntoBufferColumn(input_shape, w, h, b, kheight, kwidth, stride_width,
                                     stride_height, pad_width, pad_height, input_width,
                                     input_height, input_depth, output_depth, buffer_id, input_data,
                                     output_data, zero_byte);
        ++buffer_id;
      }
    }
  }
}
 
} // namespace ruy
} // namespace nnfw
 
#endif // __NNFW_RUY_UTILS_H__