numeric_types.hpp

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#ifndef NEFORCE_CORE_NUMERIC_NUMERIC_TYPES_HPP__
#define NEFORCE_CORE_NUMERIC_NUMERIC_TYPES_HPP__

 
#include "NeForce/core/memory/memory.hpp"
#include "NeForce/core/numeric/numeric_traits.hpp"
NEFORCE_BEGIN_NAMESPACE__


template <typename T>
NEFORCE_CONST_FUNCTION constexpr enable_if_t<!(sizeof(T) == 16 && numeric_traits<T>::digits == 64), bool>
signbit(const T x) noexcept {
    static_assert(is_floating_point_v<T>, "floating point required");
    using UInt = make_integer_t<sizeof(T), false>;
 
    const UInt bits = *reinterpret_cast<const UInt*>(&x);
    constexpr UInt sign_mask = static_cast<UInt>(1) << (8 * sizeof(UInt) - 1);
    return (bits & sign_mask) != 0;
}
 
template <typename T>
NEFORCE_CONST_FUNCTION constexpr enable_if_t<sizeof(T) == 16 && numeric_traits<T>::digits == 64, bool>
signbit(const T x) noexcept {
    static_assert(is_floating_point_v<T>, "floating point required");
 
    struct {
        byte_t data[16];
    } buf;
    _NEFORCE memory_copy(&buf, &x, sizeof(buf));
    return (buf.data[9] & 0x80) != 0;
}
 

template <typename T>
NEFORCE_CONST_FUNCTION constexpr bool is_nan(const T x) noexcept {
    static_assert(is_floating_point_v<T>, "floating point required");
    return x != x;
}

template <typename T>
NEFORCE_CONST_FUNCTION constexpr bool is_pos_infinity(const T x) noexcept {
    static_assert(is_floating_point_v<T>, "floating point required");
    return x == numeric_traits<T>::infinity();
}

template <typename T>
NEFORCE_CONST_FUNCTION constexpr bool is_neg_infinity(const T x) noexcept {
    static_assert(is_floating_point_v<T>, "floating point required");
    return x == -numeric_traits<T>::infinity();
}

template <typename T>
NEFORCE_CONST_FUNCTION constexpr bool is_infinity(const T x) noexcept {
    return _NEFORCE is_pos_infinity(x) || _NEFORCE is_neg_infinity(x);
}

template <typename T>
NEFORCE_CONST_FUNCTION constexpr bool is_finite(const T x) noexcept {
    return !_NEFORCE is_infinity(x) && !_NEFORCE is_nan(x);
}

template <typename T>
NEFORCE_CONST_FUNCTION constexpr bool is_normal(const T x) noexcept {
    if (!_NEFORCE is_finite(x)) {
        return false;
    }
    if (x == 0) {
        return false;
    }
    const T abs = x < 0 ? -x : x;
    return abs >= numeric_traits<T>::min();
}

template <typename T>
NEFORCE_CONST_FUNCTION constexpr bool is_subnormal(const T x) noexcept {
    if (!_NEFORCE is_finite(x)) {
        return false;
    }
    if (x == 0) {
        return false;
    }
    const T abs = x < 0 ? -x : x;
    return abs < numeric_traits<T>::min();
}

template <typename T>
NEFORCE_CONST_FUNCTION constexpr bool is_positive(const T x) noexcept {
    return x > 0 || (x == 0 && !_NEFORCE signbit(x));
}

template <typename T>
NEFORCE_CONST_FUNCTION constexpr bool is_negative(const T x) noexcept {
    return x < 0 || (x == 0 && _NEFORCE signbit(x));
}
 // NumericTypeChecks
 
NEFORCE_END_NAMESPACE__
#endif // NEFORCE_CORE_NUMERIC_NUMERIC_TYPES_HPP__