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/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _TOOLS_ASM_X86_SPECIAL_INSNS_H
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#define _TOOLS_ASM_X86_SPECIAL_INSNS_H
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/* The dst parameter must be 64-bytes aligned */
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static inline void movdir64b(void *dst, const void *src)
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{
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	const struct { char _[64]; } *__src = src;
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	struct { char _[64]; } *__dst = dst;
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	/*
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	 * MOVDIR64B %(rdx), rax.
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	 *
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	 * Both __src and __dst must be memory constraints in order to tell the
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	 * compiler that no other memory accesses should be reordered around
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	 * this one.
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	 *
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	 * Also, both must be supplied as lvalues because this tells
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	 * the compiler what the object is (its size) the instruction accesses.
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	 * I.e., not the pointers but what they point to, thus the deref'ing '*'.
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	 */
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	asm volatile(".byte 0x66, 0x0f, 0x38, 0xf8, 0x02"
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		     : "+m" (*__dst)
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		     :  "m" (*__src), "a" (__dst), "d" (__src));
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}
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#endif /* _TOOLS_ASM_X86_SPECIAL_INSNS_H */
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