| /* |
| * Copyright (c) 2019-2021 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_MATH_SAFE_OPS |
| #define ARM_COMPUTE_UTILS_MATH_SAFE_OPS |
| |
| #include "arm_compute/core/Error.h" |
| #include "support/Requires.h" |
| |
| #include <limits> |
| |
| namespace arm_compute |
| { |
| namespace utils |
| { |
| namespace math |
| { |
| /** Safe integer addition between two integers. In case of an overflow |
| * the numeric max limit is return. In case of an underflow numeric max |
| * limit is return. |
| * |
| * @tparam T Integer types to add |
| * |
| * @param[in] val_a First value to add |
| * @param[in] val_b Second value to add |
| * |
| * @return The addition result |
| */ |
| template <typename T, ARM_COMPUTE_REQUIRES_TA(std::is_integral<T>::value)> |
| T safe_integer_add(T val_a, T val_b) |
| { |
| T result = 0; |
| |
| if((val_b > 0) && (val_a > std::numeric_limits<T>::max() - val_b)) |
| { |
| result = std::numeric_limits<T>::max(); |
| } |
| else if((val_b < 0) && (val_a < std::numeric_limits<T>::min() - val_b)) |
| { |
| result = std::numeric_limits<T>::min(); |
| } |
| else |
| { |
| result = val_a + val_b; |
| } |
| |
| return result; |
| } |
| |
| /** Safe integer subtraction between two integers. In case of an overflow |
| * the numeric max limit is return. In case of an underflow numeric max |
| * limit is return. |
| * |
| * @tparam T Integer types to subtract |
| * |
| * @param[in] val_a Value to subtract from |
| * @param[in] val_b Value to subtract |
| * |
| * @return The subtraction result |
| */ |
| template <typename T, ARM_COMPUTE_REQUIRES_TA(std::is_integral<T>::value)> |
| T safe_integer_sub(T val_a, T val_b) |
| { |
| T result = 0; |
| |
| if((val_b < 0) && (val_a > std::numeric_limits<T>::max() + val_b)) |
| { |
| result = std::numeric_limits<T>::max(); |
| } |
| else if((val_b > 0) && (val_a < std::numeric_limits<T>::min() + val_b)) |
| { |
| result = std::numeric_limits<T>::min(); |
| } |
| else |
| { |
| result = val_a - val_b; |
| } |
| |
| return result; |
| } |
| |
| /** Safe integer multiplication between two integers. In case of an overflow |
| * the numeric max limit is return. In case of an underflow numeric max |
| * limit is return. |
| * |
| * @tparam T Integer types to multiply |
| * |
| * @param[in] val_a First value to multiply |
| * @param[in] val_b Second value to multiply |
| * |
| * @return The multiplication result |
| */ |
| template <typename T, ARM_COMPUTE_REQUIRES_TA(std::is_integral<T>::value)> |
| T safe_integer_mul(T val_a, T val_b) |
| { |
| T result = 0; |
| |
| if(val_a > 0) |
| { |
| if((val_b > 0) && (val_a > (std::numeric_limits<T>::max() / val_b))) |
| { |
| result = std::numeric_limits<T>::max(); |
| } |
| else if(val_b < (std::numeric_limits<T>::min() / val_a)) |
| { |
| result = std::numeric_limits<T>::min(); |
| } |
| else |
| { |
| result = val_a * val_b; |
| } |
| } |
| else |
| { |
| if((val_b > 0) && (val_a < (std::numeric_limits<T>::min() / val_b))) |
| { |
| result = std::numeric_limits<T>::max(); |
| } |
| else if((val_a != 0) && (val_b < (std::numeric_limits<T>::max() / val_a))) |
| { |
| result = std::numeric_limits<T>::min(); |
| } |
| else |
| { |
| result = val_a * val_b; |
| } |
| } |
| |
| return result; |
| } |
| |
| /** Safe integer division between two integers. In case of an overflow |
| * the numeric max limit is return. In case of an underflow numeric max |
| * limit is return. |
| * |
| * @tparam T Integer types to divide |
| * |
| * @param[in] val_a Dividend value |
| * @param[in] val_b Divisor value |
| * |
| * @return The quotient |
| */ |
| template <typename T, ARM_COMPUTE_REQUIRES_TA(std::is_integral<T>::value)> |
| T safe_integer_div(T val_a, T val_b) |
| { |
| T result = 0; |
| |
| if((val_b == 0) || ((val_a == std::numeric_limits<T>::min()) && (val_b == -1))) |
| { |
| result = std::numeric_limits<T>::min(); |
| } |
| else |
| { |
| result = val_a / val_b; |
| } |
| |
| return result; |
| } |
| } // namespace cast |
| } // namespace utils |
| } // namespace arm_compute |
| #endif /* ARM_COMPUTE_UTILS_MATH_SAFE_OPS */ |