1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef _OBJTOOL_ENDIANNESS_H
3 #define _OBJTOOL_ENDIANNESS_H
4 
5 #include <arch/endianness.h>
6 #include <linux/kernel.h>
7 #include <endian.h>
8 
9 #ifndef __TARGET_BYTE_ORDER
10 #error undefined arch __TARGET_BYTE_ORDER
11 #endif
12 
13 #if __BYTE_ORDER != __TARGET_BYTE_ORDER
14 #define __NEED_BSWAP 1
15 #else
16 #define __NEED_BSWAP 0
17 #endif
18 
19 /*
20  * Does a byte swap if target endianness doesn't match the host, i.e. cross
21  * compilation for little endian on big endian and vice versa.
22  * To be used for multi-byte values conversion, which are read from / about
23  * to be written to a target native endianness ELF file.
24  */
25 #define bswap_if_needed(val)						\
26 ({									\
27 	__typeof__(val) __ret;						\
28 	switch (sizeof(val)) {						\
29 	case 8: __ret = __NEED_BSWAP ? bswap_64(val) : (val); break;	\
30 	case 4: __ret = __NEED_BSWAP ? bswap_32(val) : (val); break;	\
31 	case 2: __ret = __NEED_BSWAP ? bswap_16(val) : (val); break;	\
32 	default:							\
33 		BUILD_BUG(); break;					\
34 	}								\
35 	__ret;								\
36 })
37 
38 #endif /* _OBJTOOL_ENDIANNESS_H */
39