mirror of https://gitee.com/openkylin/linux.git
60 lines
1.3 KiB
C
60 lines
1.3 KiB
C
|
#ifndef _I386_BYTEORDER_H
|
||
|
|
#define _I386_BYTEORDER_H
|
||
|
|
|
||
|
|
#include <asm/types.h>
|
||
|
|
#include <linux/compiler.h>
|
||
|
|
|
||
|
|
#ifdef __GNUC__
|
||
|
|
|
||
|
|
/* For avoiding bswap on i386 */
|
||
|
|
#ifdef __KERNEL__
|
||
|
|
#include <linux/config.h>
|
||
|
|
#endif
|
||
|
|
|
||
|
|
static __inline__ __attribute_const__ __u32 ___arch__swab32(__u32 x)
|
||
|
|
{
|
||
|
|
#ifdef CONFIG_X86_BSWAP
|
||
|
|
__asm__("bswap %0" : "=r" (x) : "0" (x));
|
||
|
|
#else
|
||
|
|
__asm__("xchgb %b0,%h0\n\t" /* swap lower bytes */
|
||
|
|
"rorl $16,%0\n\t" /* swap words */
|
||
|
|
"xchgb %b0,%h0" /* swap higher bytes */
|
||
|
|
:"=q" (x)
|
||
|
|
: "0" (x));
|
||
|
|
#endif
|
||
|
|
return x;
|
||
|
|
}
|
||
|
|
|
||
|
|
static __inline__ __attribute_const__ __u64 ___arch__swab64(__u64 val)
|
||
|
|
{
|
||
|
|
union {
|
||
|
|
struct { __u32 a,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;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Do not define swab16. Gcc is smart enough to recognize "C" version and
|
||
|
|
convert it into rotation or exhange. */
|
||
|
|
|
||
|
|
#define __arch__swab64(x) ___arch__swab64(x)
|
||
|
|
#define __arch__swab32(x) ___arch__swab32(x)
|
||
|
|
|
||
|
|
#define __BYTEORDER_HAS_U64__
|
||
|
|
|
||
|
|
#endif /* __GNUC__ */
|
||
|
|
|
||
|
|
#include <linux/byteorder/little_endian.h>
|
||
|
|
|
||
|
|
#endif /* _I386_BYTEORDER_H */
|