/*

* Copyright (C) 2024 The Android Open Source Project

*

* 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.

*/

#pragma once

#include <stdint.h>

#include "matrix.h"

namespace samples::vectorization {

/**

* Multiplies two compatible matrices and returns the result.

*

* @tparam T The type of each matrix cell.

* @tparam M The number of rows in the left operand and the result.

* @tparam N The number of columns in the left operand, and the rows in the

* right operand.

* @tparam P The number of columns in the right operand and the result.

* @param lhs The left operand.

* @param rhs The right operand.

* @return The result of lhs * rhs.

*/

template <typename T, size_t M, size_t N, size_t P>

Matrix<M, P, T> MultiplyWithOpenMP(const Matrix<M, N, T>& lhs,

const Matrix<N, P, T>& rhs) {

Matrix<M, P, T> result;

#pragma omp simd

for (auto result_column_index = 0U; result_column_index < P;

result_column_index++) {

for (auto lhs_column_index = 0U; lhs_column_index < N; lhs_column_index++) {

auto lhs_column = lhs.column(lhs_column_index);

const T& scalar = rhs[lhs_column_index, result_column_index];

for (auto row = 0U; row < lhs_column.size(); row++) {

result[row, result_column_index] += lhs_column[row] * scalar;

}

}

}

return result;

}

} // namespace samples::vectorization