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#ifndef NUMPY_CORE_SRC_COMMON_UTILS_HPP
#define NUMPY_CORE_SRC_COMMON_UTILS_HPP
#include "npdef.hpp"
#if NP_HAS_CPP20
#include <bit>
#endif
#include <type_traits>
#include <string.h>
namespace np {
/** Create a value of type `To` from the bits of `from`.
*
* similar to `std::bit_cast` but compatible with C++17,
* should perform similar to `*reinterpret_cast<To*>(&from)`
* or through punning without expecting any undefined behaviors.
*/
template<typename To, typename From>
#if NP_HAS_BUILTIN(__builtin_bit_cast) || NP_HAS_CPP20
[[nodiscard]] constexpr
#else
inline
#endif
To BitCast(const From &from) noexcept
{
static_assert(
sizeof(To) == sizeof(From),
"both data types must have the same size");
static_assert(
std::is_trivially_copyable_v<To> &&
std::is_trivially_copyable_v<From>,
"both data types must be trivially copyable");
#if NP_HAS_CPP20
return std::bit_cast<To>(from);
#elif NP_HAS_BUILTIN(__builtin_bit_cast)
return __builtin_bit_cast(To, from);
#else
To to;
memcpy(&to, &from, sizeof(from));
return to;
#endif
}
} // namespace np
#endif // NUMPY_CORE_SRC_COMMON_UTILS_HPP
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