src/tint/utils/bytes/swap.h

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#ifndef SRC_TINT_UTILS_BYTES_SWAP_H_
#define SRC_TINT_UTILS_BYTES_SWAP_H_

#include <algorithm>
#include <array>
#include <cstdint>
#include <type_traits>
#include <utility>

#include "src/tint/utils/macros/compiler.h"
#include "src/tint/utils/memory/copy.h"

namespace tint::bytes {

/// @returns the input value with all bytes reversed
/// @param value the input value, can be any type that passes std::is_integral
///              (this includes non-obvious types like wchar_t)
template <typename T>
[[nodiscard]] inline T Swap(T value) {
    static_assert(std::is_integral_v<T>);
    std::array<std::byte, sizeof(T)> bytes;
    tint::Copy(std::span<std::byte, sizeof(T)>{bytes}, value);
    std::ranges::reverse(bytes);
    T out;
    tint::Copy(&out, 1, std::span<std::byte, sizeof(T)>{bytes});
    return out;
}

}  // namespace tint::bytes

#endif  // SRC_TINT_UTILS_BYTES_SWAP_H_