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1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9 10// Assumption: minValue < maxValue11// Assumption: minValue <= rhs <= maxValue12// Assumption: minValue <= lhs <= maxValue13// Assumption: minValue >= 014template <typename T, T minValue, T maxValue>15constexpr T euclidian_addition(T rhs, T lhs) {16 const T modulus = maxValue - minValue + 1;17 T ret = rhs + lhs;18 if (ret > maxValue)19 ret -= modulus;20 return ret;21}22 23// Assumption: minValue < maxValue24// Assumption: minValue <= rhs <= maxValue25// Assumption: minValue <= lhs <= maxValue26// Assumption: minValue >= 027template <typename T, T minValue, T maxValue>28constexpr T euclidian_subtraction(T lhs, T rhs) {29 const T modulus = maxValue - minValue + 1;30 T ret = lhs - rhs;31 if (ret < minValue)32 ret += modulus;33 if (ret > maxValue) // this can happen if T is unsigned34 ret += modulus;35 return ret;36}37