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