chromium/third_party/tflite/src/tensorflow/lite/kernels/internal/reference/depthwiseconv_uint8.h

/* Copyright 2017 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 TENSORFLOW_LITE_KERNELS_INTERNAL_REFERENCE_DEPTHWISECONV_UINT8_H_
#define TENSORFLOW_LITE_KERNELS_INTERNAL_REFERENCE_DEPTHWISECONV_UINT8_H_

#include <algorithm>

#include "fixedpoint/fixedpoint.h"
#include "tensorflow/lite/kernels/internal/common.h"
#include "tensorflow/lite/kernels/internal/compatibility.h"
#include "tensorflow/lite/kernels/internal/types.h"

namespace tflite {

// Used in tests and template parameters to control which version of depthwise
// convolution is called. Primarily for reference code, and specializations
// forced in tests.
enum class DepthwiseConvImplementation { … };

// Category of depthwise convolution output rounding.
enum class DepthwiseConvOutputRounding { … };

// Category of depthwise convolution depth multiplication.
enum class DepthwiseConvDepthMultiplication { … };

namespace reference_ops {
namespace depthwise_conv {

template <DepthwiseConvOutputRounding output_rounding>
inline int32_t DepthwiseConvRound(int32_t x, int32_t quantized_multiplier,
                                  int shift) { … }

// Single-rounding MultiplyByQuantizedMultiplier
#if TFLITE_SINGLE_ROUNDING
template <>
inline int32_t DepthwiseConvRound<DepthwiseConvOutputRounding::kAwayFromZero>(
    int32_t x, int32_t quantized_multiplier, int shift) {
  using gemmlowp::RoundingDivideByPOT;
  using gemmlowp::SaturatingRoundingDoublingHighMul;
  int left_shift = shift > 0 ? shift : 0;
  int right_shift = shift > 0 ? 0 : -shift;
  return RoundingDivideByPOT(SaturatingRoundingDoublingHighMul(
                                 x * (1 << left_shift), quantized_multiplier),
                             right_shift);
}

template <>
inline int32_t DepthwiseConvRound<DepthwiseConvOutputRounding::kUpward>(
    int32_t x, int32_t quantized_multiplier, int shift) {
  return MultiplyByQuantizedMultiplier(x, quantized_multiplier, shift);
}
// Double-rounding MultiplyByQuantizedMultiplier
#else
template <>
inline int32_t DepthwiseConvRound<DepthwiseConvOutputRounding::kAwayFromZero>(
    int32_t x, int32_t quantized_multiplier, int shift) { … }

template <>
inline int32_t DepthwiseConvRound<DepthwiseConvOutputRounding::kUpward>(
    int32_t x, int32_t quantized_multiplier, int shift) { … }
#endif  // TFLITE_SINGLE_ROUNDING

template <DepthwiseConvOutputRounding output_rounding>
struct DepthwiseConvBasicKernel { … };

}  // namespace depthwise_conv

inline void DepthwiseConv(
    const DepthwiseParams& params, const RuntimeShape& input_shape,
    const uint8_t* input_data, const RuntimeShape& filter_shape,
    const uint8_t* filter_data, const RuntimeShape& bias_shape,
    const int32_t* bias_data, const RuntimeShape& output_shape,
    uint8_t* output_data) { … }

}  // namespace reference_ops
}  // end namespace tflite

#endif  // TENSORFLOW_LITE_KERNELS_INTERNAL_REFERENCE_DEPTHWISECONV_UINT8_H_