linux/arch/x86/include/asm/swab.h

62 lines
1.2 KiB
C

#ifndef _ASM_X86_SWAB_H
#define _ASM_X86_SWAB_H
#include <asm/types.h>
#include <linux/compiler.h>
static inline __attribute_const__ __u32 __arch_swab32(__u32 val)
{
#ifdef __i386__
# ifdef CONFIG_X86_BSWAP
asm("bswap %0" : "=r" (val) : "0" (val));
# else
asm("xchgb %b0,%h0\n\t" /* swap lower bytes */
"rorl $16,%0\n\t" /* swap words */
"xchgb %b0,%h0" /* swap higher bytes */
: "=q" (val)
: "0" (val));
# endif
#else /* __i386__ */
asm("bswapl %0"
: "=r" (val)
: "0" (val));
#endif
return val;
}
#define __arch_swab32 __arch_swab32
static inline __attribute_const__ __u64 __arch_swab64(__u64 val)
{
#ifdef __i386__
union {
struct {
__u32 a;
__u32 b;
} s;
__u64 u;
} v;
v.u = val;
# ifdef CONFIG_X86_BSWAP
asm("bswapl %0 ; bswapl %1 ; xchgl %0,%1"
: "=r" (v.s.a), "=r" (v.s.b)
: "0" (v.s.a), "1" (v.s.b));
# else
v.s.a = __arch_swab32(v.s.a);
v.s.b = __arch_swab32(v.s.b);
asm("xchgl %0,%1"
: "=r" (v.s.a), "=r" (v.s.b)
: "0" (v.s.a), "1" (v.s.b));
# endif
return v.u;
#else /* __i386__ */
asm("bswapq %0"
: "=r" (val)
: "0" (val));
return val;
#endif
}
#define __arch_swab64 __arch_swab64
#endif /* _ASM_X86_SWAB_H */