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

46 lines
965 B
C

#ifndef ETHERBOOT_BITS_BYTESWAP_H
#define ETHERBOOT_BITS_BYTESWAP_H
static inline uint16_t __i386_bswap_16(uint16_t x)
{
__asm__("xchgb %b0,%h0\n\t"
: "=q" (x)
: "0" (x));
return x;
}
static inline 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;
}
#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_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)))
#endif /* ETHERBOOT_BITS_BYTESWAP_H */