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8bfe273238
Correct objtool orc generation endianness problems to enable fully functional x86 cross-compiles on big endian hardware. Introduce bswap_if_needed() macro, which does a byte swap if target endianness doesn't match the host, i.e. cross-compilation for little endian on big endian and vice versa. The macro is used for conversion of multi-byte values which are read from / about to be written to a target native endianness ELF file. Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
39 lines
1.0 KiB
C
39 lines
1.0 KiB
C
/* SPDX-License-Identifier: GPL-2.0-or-later */
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#ifndef _OBJTOOL_ENDIANNESS_H
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#define _OBJTOOL_ENDIANNESS_H
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#include <linux/kernel.h>
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#include <endian.h>
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#include "arch_endianness.h"
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#ifndef __TARGET_BYTE_ORDER
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#error undefined arch __TARGET_BYTE_ORDER
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#endif
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#if __BYTE_ORDER != __TARGET_BYTE_ORDER
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#define __NEED_BSWAP 1
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#else
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#define __NEED_BSWAP 0
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#endif
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/*
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* Does a byte swap if target endianness doesn't match the host, i.e. cross
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* compilation for little endian on big endian and vice versa.
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* To be used for multi-byte values conversion, which are read from / about
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* to be written to a target native endianness ELF file.
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*/
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#define bswap_if_needed(val) \
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({ \
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__typeof__(val) __ret; \
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switch (sizeof(val)) { \
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case 8: __ret = __NEED_BSWAP ? bswap_64(val) : (val); break; \
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case 4: __ret = __NEED_BSWAP ? bswap_32(val) : (val); break; \
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case 2: __ret = __NEED_BSWAP ? bswap_16(val) : (val); break; \
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default: \
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BUILD_BUG(); break; \
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} \
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__ret; \
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})
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#endif /* _OBJTOOL_ENDIANNESS_H */
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