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 <cstdint>
#include <cstring>
#include <type_traits>
#include <utility>

namespace tint::bytes {

/// @return the input integer value with all bytes reversed
/// @param value the input value
template <typename T>
[[nodiscard]] inline T Swap(T value) {
    static_assert(std::is_integral_v<T>);
    uint8_t bytes[sizeof(T)];
    memcpy(bytes, &value, sizeof(T));
    for (size_t i = 0; i < sizeof(T) / 2; i++) {
        std::swap(bytes[i], bytes[sizeof(T) - i - 1]);
    }
    T out;
    memcpy(&out, bytes, sizeof(T));
    return out;
}

}  // namespace tint::bytes

#endif  // SRC_TINT_UTILS_BYTES_SWAP_H_