diff options
Diffstat (limited to 'src/bit.h')
| -rw-r--r-- | src/bit.h | 102 |
1 files changed, 90 insertions, 12 deletions
@@ -8,11 +8,12 @@ #ifndef BFS_BIT_H #define BFS_BIT_H -#include "prelude.h" +#include "bfs.h" + #include <limits.h> #include <stdint.h> -#if BFS_HAS_STDBIT_H +#if __has_include(<stdbit.h>) # include <stdbit.h> #endif @@ -147,7 +148,7 @@ # define INTMAX_WIDTH UINTMAX_WIDTH #endif -// C23 polyfill: byte order +// N3022 polyfill: byte order #ifdef __STDC_ENDIAN_LITTLE__ # define ENDIAN_LITTLE __STDC_ENDIAN_LITTLE__ @@ -197,15 +198,35 @@ static inline uint8_t bswap_u8(uint8_t n) { return n; } -/** - * Reverse the byte order of an integer. - */ -#define bswap(n) \ - _Generic((n), \ - uint8_t: bswap_u8, \ - uint16_t: bswap_u16, \ - uint32_t: bswap_u32, \ - uint64_t: bswap_u64)(n) +#if UCHAR_WIDTH == 8 +# define bswap_uc bswap_u8 +#endif + +#if USHRT_WIDTH == 16 +# define bswap_us bswap_u16 +#elif USHRT_WIDTH == 32 +# define bswap_us bswap_u32 +#elif USHRT_WIDTH == 64 +# define bswap_us bswap_u64 +#endif + +#if UINT_WIDTH == 16 +# define bswap_ui bswap_u16 +#elif UINT_WIDTH == 32 +# define bswap_ui bswap_u32 +#elif UINT_WIDTH == 64 +# define bswap_ui bswap_u64 +#endif + +#if ULONG_WIDTH == 32 +# define bswap_ul bswap_u32 +#elif ULONG_WIDTH == 64 +# define bswap_ul bswap_u64 +#endif + +#if ULLONG_WIDTH == 64 +# define bswap_ull bswap_u64 +#endif // Define an overload for each unsigned type #define UINT_OVERLOADS(macro) \ @@ -224,6 +245,63 @@ static inline uint8_t bswap_u8(uint8_t n) { unsigned long: name##_ul, \ unsigned long long: name##_ull) +/** + * Reverse the byte order of an integer. + */ +#define bswap(n) UINT_SELECT(n, bswap)(n) + +#define LOAD8_LEU8(ptr, i, n) ((uint##n##_t)((const unsigned char *)ptr)[(i) / 8] << (i)) +#define LOAD8_BEU8(ptr, i, n) ((uint##n##_t)((const unsigned char *)ptr)[(i) / 8] << (n - (i) - 8)) + +/** Load a little-endian 8-bit word. */ +static inline uint8_t load8_leu8(const void *ptr) { + return LOAD8_LEU8(ptr, 0, 8); +} + +/** Load a big-endian 8-bit word. */ +static inline uint8_t load8_beu8(const void *ptr) { + return LOAD8_BEU8(ptr, 0, 8); +} + +#define LOAD8_LEU16(ptr, i, n) (LOAD8_LEU8(ptr, i, n) | LOAD8_LEU8(ptr, i + 8, n)) +#define LOAD8_BEU16(ptr, i, n) (LOAD8_BEU8(ptr, i, n) | LOAD8_BEU8(ptr, i + 8, n)) + +/** Load a little-endian 16-bit word. */ +static inline uint16_t load8_leu16(const void *ptr) { + return LOAD8_LEU16(ptr, 0, 16); +} + +/** Load a big-endian 16-bit word. */ +static inline uint16_t load8_beu16(const void *ptr) { + return LOAD8_BEU16(ptr, 0, 16); +} + +#define LOAD8_LEU32(ptr, i, n) (LOAD8_LEU16(ptr, i, n) | LOAD8_LEU16(ptr, i + 16, n)) +#define LOAD8_BEU32(ptr, i, n) (LOAD8_BEU16(ptr, i, n) | LOAD8_BEU16(ptr, i + 16, n)) + +/** Load a little-endian 32-bit word. */ +static inline uint32_t load8_leu32(const void *ptr) { + return LOAD8_LEU32(ptr, 0, 32); +} + +/** Load a big-endian 32-bit word. */ +static inline uint32_t load8_beu32(const void *ptr) { + return LOAD8_BEU32(ptr, 0, 32); +} + +#define LOAD8_LEU64(ptr, i, n) (LOAD8_LEU32(ptr, i, n) | LOAD8_LEU32(ptr, i + 32, n)) +#define LOAD8_BEU64(ptr, i, n) (LOAD8_BEU32(ptr, i, n) | LOAD8_BEU32(ptr, i + 32, n)) + +/** Load a little-endian 64-bit word. */ +static inline uint64_t load8_leu64(const void *ptr) { + return LOAD8_LEU64(ptr, 0, 64); +} + +/** Load a big-endian 64-bit word. */ +static inline uint64_t load8_beu64(const void *ptr) { + return LOAD8_BEU64(ptr, 0, 64); +} + // C23 polyfill: bit utilities #if __STDC_VERSION_STDBIT_H__ >= C23 |