| /* |
| * Copyright (c) 2018-2021, 2023 Arm Limited. |
| * |
| * SPDX-License-Identifier: MIT |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to |
| * deal in the Software without restriction, including without limitation the |
| * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or |
| * sell copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in all |
| * copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| * SOFTWARE. |
| */ |
| #ifndef ARM_COMPUTE_UTILS_ROUNDING_H |
| #define ARM_COMPUTE_UTILS_ROUNDING_H |
| |
| #include "arm_compute/core/Error.h" |
| #include "arm_compute/core/utils/misc/Traits.h" |
| |
| #include "support/AclRequires.h" |
| #include "support/ToolchainSupport.h" |
| |
| #include <cmath> |
| |
| namespace arm_compute |
| { |
| namespace utils |
| { |
| namespace rounding |
| { |
| /** Rounding mode */ |
| enum class RoundingMode |
| { |
| TO_ZERO, /**< Round towards zero */ |
| AWAY_FROM_ZERO, /**< Round away from zero */ |
| HALF_TO_ZERO, /**< Round half towards from zero */ |
| HALF_AWAY_FROM_ZERO, /**< Round half away from zero */ |
| HALF_UP, /**< Round half towards positive infinity */ |
| HALF_DOWN, /**< Round half towards negative infinity */ |
| HALF_EVEN /**< Round half towards nearest even */ |
| }; |
| |
| /** Round floating-point value with round to zero |
| * |
| * @tparam T Parameter type. Should be of floating point type. |
| * |
| * @param[in] value floating-point value to be rounded. |
| * |
| * @return Floating-point value of rounded @p value. |
| */ |
| template <typename T, ARM_COMPUTE_REQUIRES_TA(traits::is_floating_point<T>::value)> |
| inline T round_to_zero(T value) |
| { |
| T res = std::floor(std::fabs(value)); |
| return (value < 0.f) ? -res : res; |
| } |
| |
| /** Round floating-point value with round away from zero |
| * |
| * @tparam T Parameter type. Should be of floating point type. |
| * |
| * @param[in] value floating-point value to be rounded. |
| * |
| * @return Floating-point value of rounded @p value. |
| */ |
| template <typename T, ARM_COMPUTE_REQUIRES_TA(traits::is_floating_point<T>::value)> |
| inline T round_away_from_zero(T value) |
| { |
| T res = std::ceil(std::fabs(value)); |
| return (value < 0.f) ? -res : res; |
| } |
| |
| /** Round floating-point value with half value rounding towards zero. |
| * |
| * @tparam T Parameter type. Should be of floating point type. |
| * |
| * @param[in] value floating-point value to be rounded. |
| * |
| * @return Floating-point value of rounded @p value. |
| */ |
| template <typename T, ARM_COMPUTE_REQUIRES_TA(traits::is_floating_point<T>::value)> |
| inline T round_half_to_zero(T value) |
| { |
| T res = T(std::ceil(std::fabs(value) - 0.5f)); |
| return (value < 0.f) ? -res : res; |
| } |
| |
| /** Round floating-point value with half value rounding away from zero. |
| * |
| * @tparam T Parameter type. Should be of floating point type. |
| * |
| * @param[in] value floating-point value to be rounded. |
| * |
| * @return Floating-point value of rounded @p value. |
| */ |
| template <typename T, ARM_COMPUTE_REQUIRES_TA(traits::is_floating_point<T>::value)> |
| inline T round_half_away_from_zero(T value) |
| { |
| T res = T(std::floor(std::fabs(value) + 0.5f)); |
| return (value < 0.f) ? -res : res; |
| } |
| |
| /** Round floating-point value with half value rounding to positive infinity. |
| * |
| * @tparam T Parameter type. Should be of floating point type. |
| * |
| * @param[in] value floating-point value to be rounded. |
| * |
| * @return Floating-point value of rounded @p value. |
| */ |
| template <typename T, ARM_COMPUTE_REQUIRES_TA(traits::is_floating_point<T>::value)> |
| inline T round_half_up(T value) |
| { |
| return std::floor(value + 0.5f); |
| } |
| |
| /** Round floating-point value with half value rounding to negative infinity. |
| * |
| * @tparam T Parameter type. Should be of floating point type. |
| * |
| * @param[in] value floating-point value to be rounded. |
| * |
| * @return Floating-point value of rounded @p value. |
| */ |
| template <typename T, ARM_COMPUTE_REQUIRES_TA(traits::is_floating_point<T>::value)> |
| inline T round_half_down(T value) |
| { |
| return std::ceil(value - 0.5f); |
| } |
| |
| /** Round floating-point value with half value rounding to nearest even. |
| * |
| * @tparam T Parameter type. Should be of floating point type. |
| * |
| * @param[in] value floating-point value to be rounded. |
| * @param[in] epsilon precision. |
| * |
| * @return Floating-point value of rounded @p value. |
| */ |
| template <typename T, ARM_COMPUTE_REQUIRES_TA(traits::is_floating_point<T>::value)> |
| inline T round_half_even(T value, T epsilon = std::numeric_limits<T>::epsilon()) |
| { |
| T positive_value = std::abs(value); |
| T ipart = 0; |
| std::modf(positive_value, &ipart); |
| // If 'value' is exactly halfway between two integers |
| if (std::abs(positive_value - (ipart + 0.5f)) < epsilon) |
| { |
| // If 'ipart' is even then return 'ipart' |
| if (std::fmod(ipart, 2.f) < epsilon) |
| { |
| return support::cpp11::copysign(ipart, value); |
| } |
| // Else return the nearest even integer |
| return support::cpp11::copysign(std::ceil(ipart + 0.5f), value); |
| } |
| // Otherwise use the usual round to closest |
| return support::cpp11::copysign(support::cpp11::round(positive_value), value); |
| } |
| |
| /** Round floating-point value given a rounding mode |
| * |
| * @tparam T Parameter type. Should be of floating point type. |
| * |
| * @param[in] value floating-point value to be rounded. |
| * @param[in] rounding_mode Rounding mode to use. |
| * |
| * @return Floating-point value of rounded @p value. |
| */ |
| template <typename T, ARM_COMPUTE_REQUIRES_TA(traits::is_floating_point<T>::value)> |
| inline T round(T value, RoundingMode rounding_mode) |
| { |
| switch (rounding_mode) |
| { |
| case RoundingMode::TO_ZERO: |
| return round_to_zero(value); |
| case RoundingMode::AWAY_FROM_ZERO: |
| return round_away_from_zero(value); |
| case RoundingMode::HALF_TO_ZERO: |
| return round_half_to_zero(value); |
| case RoundingMode::HALF_AWAY_FROM_ZERO: |
| return round_half_away_from_zero(value); |
| case RoundingMode::HALF_UP: |
| return round_half_up(value); |
| case RoundingMode::HALF_DOWN: |
| return round_half_down(value); |
| case RoundingMode::HALF_EVEN: |
| return round_half_even(value); |
| default: |
| ARM_COMPUTE_ERROR("Unsupported rounding mode!"); |
| } |
| } |
| } // namespace rounding |
| } // namespace utils |
| } // namespace arm_compute |
| #endif /*ARM_COMPUTE_UTILS_ROUNDING_H */ |