main.asm

format elf64 executable

include "macros.inc"

macro syscall1 number, arg1 {
    mov rax, number
    mov rdi, arg1
    syscall
}

macro syscall2 number, arg1, arg2 {
    mov rax, number
    mov rdi, arg1
    mov rsi, arg2
    syscall
}

macro syscall3 number, arg1, arg2, arg3 {
    mov rax, number
    mov rdi, arg1
    mov rsi, arg2
    mov rdx, arg3
    syscall
}

macro exit code {
sys_exit  = 60
    syscall1 sys_exit, code
}


macro write fd, buf, len {
sys_write = 1
    syscall3 sys_write, fd, buf, len
}

STDIN_FILENO  = 0
STDOUT_FILENO = 1
STDERR_FILENO = 2
EXIT_SUCCESS = 0
EXIT_FAILURE = 1


entry _start
_start:
    for r14, 10, 0, -1
        for r15, 0, 5, 1
            write STDOUT_FILENO, hello, hello.len
        endfor
    endfor
    exit EXIT_SUCCESS


struc cstr [data] {
    common
    . db data,0
    .len = $ - . - 1
}
hello cstr 'hello',10