1 #ifndef _BITS_BYTESWAP_H
2 #define _BITS_BYTESWAP_H
3 
4 /** @file
5  *
6  * Byte-order swapping functions
7  *
8  */
9 
10 #include <stdint.h>
11 
12 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
13 
14 static inline __attribute__ (( always_inline, const )) uint16_t
__bswap_variable_16(uint16_t x)15 __bswap_variable_16 ( uint16_t x ) {
16 	__asm__ ( "xchgb %b0,%h0" : "=Q" ( x ) : "0" ( x ) );
17 	return x;
18 }
19 
20 static inline __attribute__ (( always_inline )) void
__bswap_16s(uint16_t * x)21 __bswap_16s ( uint16_t *x ) {
22 	__asm__ ( "rorw $8, %0" : "+m" ( *x ) );
23 }
24 
25 static inline __attribute__ (( always_inline, const )) uint32_t
__bswap_variable_32(uint32_t x)26 __bswap_variable_32 ( uint32_t x ) {
27 	__asm__ ( "bswapl %k0" : "=r" ( x ) : "0" ( x ) );
28 	return x;
29 }
30 
31 static inline __attribute__ (( always_inline )) void
__bswap_32s(uint32_t * x)32 __bswap_32s ( uint32_t *x ) {
33 	__asm__ ( "bswapl %k0" : "=r" ( *x ) : "0" ( *x ) );
34 }
35 
36 static inline __attribute__ (( always_inline, const )) uint64_t
__bswap_variable_64(uint64_t x)37 __bswap_variable_64 ( uint64_t x ) {
38 	__asm__ ( "bswapq %q0" : "=r" ( x ) : "0" ( x ) );
39 	return x;
40 }
41 
42 static inline __attribute__ (( always_inline )) void
__bswap_64s(uint64_t * x)43 __bswap_64s ( uint64_t *x ) {
44 	__asm__ ( "bswapq %q0" : "=r" ( *x ) : "0" ( *x ) );
45 }
46 
47 #endif /* _BITS_BYTESWAP_H */
48