/* Copyright 2020 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_DELEGATES_GPU_COMMON_WINOGRAD_UTIL_H_
#define TENSORFLOW_LITE_DELEGATES_GPU_COMMON_WINOGRAD_UTIL_H_

#include <vector>

#include "tensorflow/lite/delegates/gpu/common/data_type.h"
#include "tensorflow/lite/delegates/gpu/common/operations.h"
#include "tensorflow/lite/delegates/gpu/common/shape.h"
#include "tensorflow/lite/delegates/gpu/common/tensor.h"

namespace tflite {
namespace gpu {

// Matrices for Winograd trasformations received with method described here
// https://openreview.net/pdf?id=H1ZaRZVKg

// returns A transposed matrix(6 * 4) as array (24 values) for Winograd4x4To6x6
std::vector<float> AtMatrixForWinograd4x4To6x6();

// returns B transposed matrix(6 * 6) as array (36 values) for Winograd4x4To6x6
std::vector<float> BtMatrixForWinograd4x4To6x6();

void RearrangeWeightsToWinograd4x4To6x6Weights(
    const Tensor<OHWI, DataType::FLOAT32>& src_weights,
    Tensor<OHWI, DataType::FLOAT32>* dst_weights);

bool IsSuitableForWinograd4x4To6x6(const Convolution2DAttributes& attr);

}  // namespace gpu
}  // namespace tflite

#endif  // TENSORFLOW_LITE_DELEGATES_GPU_COMMON_WINOGRAD_UTIL_H_
