Numeric.h

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/* Copyright (c) 2024 Skyward Experimental Rocketry
 * Authors: Niccolò Betto, Damiano Procaccia
 *
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 * The above copyright notice and this permission notice shall be included in
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#pragma once
 
#include <limits>
#include <type_traits>
 
namespace Boardcore
{
 
template <class T>
constexpr auto add_sat(T x, T y) noexcept ->
    typename std::enable_if_t<std::is_integral<T>::value, T>
{
    auto result = T{};
    // The built-in function returns true if the addition overflows
    bool overflow = __builtin_add_overflow(x, y, &result);
 
    if (!overflow)
        return result;
 
    if (x < 0)
        return std::numeric_limits<T>::min();
    else
        return std::numeric_limits<T>::max();
}
 
}  // namespace Boardcore