FilesExpand file tree

master

/

swap.hpp

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

78 lines (76 loc) · 2.18 KB

master

/

swap.hpp

Copy path

Top

File metadata and controls

• Code
• Blame

78 lines (76 loc) · 2.18 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

#if __cplusplus >= 202101L // "C++23";

#include <bit>

#define bswap16(x) std::byteswap<uint16_t>(x)

#define bswap32(x) std::byteswap<uint32_t>(x)

#define bswap64(x) std::byteswap<uint64_t>(x)

#else

// set swap funcions (source: old version of nodejs/src/node_buffer.cc)

#if defined(__GNUC__) || defined(__clang__)

#define bswap16(x) __builtin_bswap16(x)

#define bswap32(x) __builtin_bswap32(x)

#define bswap64(x) __builtin_bswap64(x)

#elif defined(__linux__)

#include <byteswap.h>

#define bswap16(x) bswap_16(x)

#define bswap32(x) bswap_32(x)

#define bswap64(x) bswap_64(x)

#elif defined(_MSC_VER)

#include <intrin.h>

#define bswap16(x) _byteswap_ushort(x)

#define bswap32(x) _byteswap_ulong(x)

#define bswap64(x) _byteswap_uint64(x)

#else

#ifdef __builtin_bswap16

#define bswap16(x) __builtin_bswap16(x)

#else

#define bswap16 ((x) << 8) | ((x) >> 8)

#endif

#ifdef __builtin_bswap32

#define bswap32(x) __builtin_bswap32(x)

#else

#define bswap32 \

(((x) & 0xFF) << 24) | \

(((x) & 0xFF00) << 8) | \

(((x) >> 8) & 0xFF00) | \

(((x) >> 24) & 0xFF)

#endif

#ifdef __builtin_bswap64

#define bswap64 __builtin_bswap64(x)

#else

#define bswap64 \

(((x) & 0xFF00000000000000ull) >> 56) | \

(((x) & 0x00FF000000000000ull) >> 40) | \

(((x) & 0x0000FF0000000000ull) >> 24) | \

(((x) & 0x000000FF00000000ull) >> 8) | \

(((x) & 0x00000000FF000000ull) << 8) | \

(((x) & 0x0000000000FF0000ull) << 24) | \

(((x) & 0x000000000000FF00ull) << 40) | \

(((x) & 0x00000000000000FFull) << 56)

#endif

#endif

#endif

template<typename T>

inline void swap_any_inplace(T *x)

{

if constexpr (sizeof(T) == 1)

{

// do nothing

}

else if constexpr (sizeof(T) == 2)

{

*(uint16_t *)x = bswap16(*(uint16_t *)x);

}

else if constexpr (sizeof(T) == 4)

{

*(uint32_t *)x = bswap32(*(uint32_t *)x);

}

else if constexpr (sizeof(T) == 8)

{

*(uint64_t *)x = bswap64(*(uint64_t *)x);

}

else

{

// gcc is tripping and somehow reaching this at compile time

// static_assert(false, "Swap not implemented for this size");

}

}