opengnsys_ipxe/src/arch/i386/include/bits/byteswap.h

77 lines
2.0 KiB
C

#ifndef ETHERBOOT_BITS_BYTESWAP_H
#define ETHERBOOT_BITS_BYTESWAP_H
static inline __attribute__ ((always_inline, const)) uint16_t
__i386_bswap_16(uint16_t x)
{
__asm__("xchgb %b0,%h0\n\t"
: "=q" (x)
: "0" (x));
return x;
}
static inline __attribute__ ((always_inline, const)) uint32_t
__i386_bswap_32(uint32_t x)
{
__asm__("xchgb %b0,%h0\n\t"
"rorl $16,%0\n\t"
"xchgb %b0,%h0"
: "=q" (x)
: "0" (x));
return x;
}
static inline __attribute__ ((always_inline, const)) uint64_t
__i386_bswap_64(uint64_t x)
{
union {
uint64_t qword;
uint32_t dword[2];
} u;
u.qword = x;
u.dword[0] = __i386_bswap_32(u.dword[0]);
u.dword[1] = __i386_bswap_32(u.dword[1]);
__asm__("xchgl %0,%1"
: "=r" ( u.dword[0] ), "=r" ( u.dword[1] )
: "0" ( u.dword[0] ), "1" ( u.dword[1] ) );
return u.qword;
}
#define __bswap_constant_16(x) \
((uint16_t)((((uint16_t)(x) & 0x00ff) << 8) | \
(((uint16_t)(x) & 0xff00) >> 8)))
#define __bswap_constant_32(x) \
((uint32_t)((((uint32_t)(x) & 0x000000ffU) << 24) | \
(((uint32_t)(x) & 0x0000ff00U) << 8) | \
(((uint32_t)(x) & 0x00ff0000U) >> 8) | \
(((uint32_t)(x) & 0xff000000U) >> 24)))
#define __bswap_constant_64(x) \
((uint64_t)((((uint64_t)(x) & 0x00000000000000ffULL) << 56) | \
(((uint64_t)(x) & 0x000000000000ff00ULL) << 40) | \
(((uint64_t)(x) & 0x0000000000ff0000ULL) << 24) | \
(((uint64_t)(x) & 0x00000000ff000000ULL) << 8) | \
(((uint64_t)(x) & 0x000000ff00000000ULL) >> 8) | \
(((uint64_t)(x) & 0x0000ff0000000000ULL) >> 24) | \
(((uint64_t)(x) & 0x00ff000000000000ULL) >> 40) | \
(((uint64_t)(x) & 0xff00000000000000ULL) >> 56)))
#define __bswap_16(x) \
((uint16_t)(__builtin_constant_p(x) ? \
__bswap_constant_16(x) : \
__i386_bswap_16(x)))
#define __bswap_32(x) \
((uint32_t)(__builtin_constant_p(x) ? \
__bswap_constant_32(x) : \
__i386_bswap_32(x)))
#define __bswap_64(x) \
((uint64_t)(__builtin_constant_p(x) ? \
__bswap_constant_64(x) : \
__i386_bswap_64(x)))
#endif /* ETHERBOOT_BITS_BYTESWAP_H */