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/* SPDX-License-Identifier: GPL-2.0-or-later */ #ifndef _OBJTOOL_ENDIANNESS_H #define _OBJTOOL_ENDIANNESS_H #include <linux/kernel.h> #include <endian.h> #include <objtool/elf.h> /* * Does a byte swap if target file endianness doesn't match the host, i.e. cross * compilation for little endian on big endian and vice versa. * To be used for multi-byte values conversion, which are read from / about * to be written to a target native endianness ELF file. */ static inline bool need_bswap(struct elf *elf) { return (__BYTE_ORDER == __LITTLE_ENDIAN) ^ (elf->ehdr.e_ident[EI_DATA] == ELFDATA2LSB); } #define bswap_if_needed(elf, val) \ ({ \ __typeof__(val) __ret; \ bool __need_bswap = need_bswap(elf); \ switch (sizeof(val)) { \ case 8: \ __ret = __need_bswap ? bswap_64(val) : (val); break; \ case 4: \ __ret = __need_bswap ? bswap_32(val) : (val); break; \ case 2: \ __ret = __need_bswap ? bswap_16(val) : (val); break; \ default: \ BUILD_BUG(); break; \ } \ __ret; \ }) #endif /* _OBJTOOL_ENDIANNESS_H */