xref: /linux/arch/x86/include/uapi/asm/swab.h (revision 2697b79a469b68e3ad3640f55284359c1396278d)
1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 #ifndef _ASM_X86_SWAB_H
3 #define _ASM_X86_SWAB_H
4 
5 #include <linux/types.h>
6 #include <linux/compiler.h>
7 
8 static inline __attribute_const__ __u32 __arch_swab32(__u32 val)
9 {
10 	asm("bswapl %0" : "=r" (val) : "0" (val));
11 	return val;
12 }
13 #define __arch_swab32 __arch_swab32
14 
15 static inline __attribute_const__ __u64 __arch_swab64(__u64 val)
16 {
17 #ifdef __i386__
18 	union {
19 		struct {
20 			__u32 a;
21 			__u32 b;
22 		} s;
23 		__u64 u;
24 	} v;
25 	v.u = val;
26 	asm("bswapl %0 ; bswapl %1 ; xchgl %0,%1"
27 	    : "=r" (v.s.a), "=r" (v.s.b)
28 	    : "0" (v.s.a), "1" (v.s.b));
29 	return v.u;
30 #else /* __i386__ */
31 	asm("bswapq %0" : "=r" (val) : "0" (val));
32 	return val;
33 #endif
34 }
35 #define __arch_swab64 __arch_swab64
36 
37 #endif /* _ASM_X86_SWAB_H */
38