dingusppc/endianswap.h
Maxim Poliakovski 720b35aa26 Move endian swapping code to endianswap.h.
Remove superfluous endian swapping wrappers.
2020-01-12 22:51:37 +01:00

52 lines
1.5 KiB
C

/** @file Macros for performing byte swapping for quick endian conversion.
It will try to use the fast built-in machine instructions first
and fall back to the slow conversion if none were found.
*/
#ifndef ENDIAN_SWAP_H
#define ENDIAN_SWAP_H
#ifdef __GNUG__ /* GCC, ICC and Clang */
# ifdef __APPLE__
# include <machine/endian.h>
# else
# include <endian.h>
# endif
# define BYTESWAP_16(x) (__builtin_bswap16 (x))
# define BYTESWAP_32(x) (__builtin_bswap32 (x))
# define BYTESWAP_64(x) (__builtin_bswap64 (x))
#elif _MSC_VER /* MSVC */
# include <stdlib.h>
# define BYTESWAP_16(x) (_byteswap_ushort (x))
# define BYTESWAP_32(x) (_byteswap_ulong (x))
# define BYTESWAP_64(x) (_byteswap_uint64 (x))
#else
# warning "Unknown byte swapping built-ins (do it the slow way)!"
# define BYTESWAP_16(x) ((x) >> 8) | (((x) & 0xFFUL) << 8)
# define BYTESWAP_32(x) ((x) >> 24) | (((x) >> 8) & 0xFF00UL) | \
(((x) & 0xFF00UL) << 8) | ((x) << 24)
# define BYTESWAP_64(x) \
((x) >> 56) | \
(((x) & 0x00FF000000000000ULL) >> 48) | \
(((x) & 0x0000FF0000000000ULL) >> 40) | \
(((x) & 0x000000FF00000000ULL) >> 32) | \
(((x) & 0x00000000FF000000ULL) << 32) | \
(((x) & 0x0000000000FF0000ULL) << 40) | \
(((x) & 0x000000000000FF00ULL) << 48) | \
(((x) & 0x00000000000000FFULL) << 56)
#endif
#endif /* ENDIAN_SWAP_H */