MOVRS - x86-64 instruction reference

movrsMove with read-shared hint 
Loads a register from memory using the MOVRS encoding, which hints that the data is read-shared.
Processors with the MOVRS extension
CFPFAFZFSFDFOF –––––––
Changes no flag
Forms  movrs ,  8163264 
Operands reg A general-purpose register matching the operation’s size, for example al, ax, eax or rax. The byte registers ah, bh, ch and dh cannot be used with a REX prefix, which is required by spl, bpl, sil, dil and r8–r15. 
mem A memory location addressed with square brackets, for example [rbx+8] or [label]. 
 global _start

section .data
value: dq 7

section .text
_start:
        mov rax, 12
        mov rbx, 5
        mov rcx, 3
        mov rsi, 9

        movrs rax, [value]

        mov rax, 60         ; syscall 60: exit
        xor rdi, rdi
        syscall