.text _start: movq %dr8, %rax movq %dr8, %rdi movq %rax, %dr8 movq %rdi, %dr8 .att_syntax noprefix movq dr8, rax movq dr8, rdi movq rax, dr8 movq rdi, dr8 .intel_syntax noprefix mov rax, dr8 mov rdi, dr8 mov dr8, rax mov dr8, rdi