%define STDOUT 1

%define WRITE 4

%define _EXIT 1

global _start

_start:

mov rbx, STDOUT

mov rdx, derp

call rdx

db "this is a test", 0x0A

derp:

pop rcx

sub rdx, rcx

mov rax, WRITE

int 0x80

_exit:

mov rbx, 0

mov rax, _EXIT

int 0x80