bits 64
section .data
    big_endian db "big endian", 0xA
    little_endian db "little endian", 0xA
    len1 equ $ - big_endian
    len2 equ $ - big_endian

section .text
global _start
_start:
    mov rsi, 0
    mov word [rsi], 0x1A3C
    ; mov ax, word [0]
    mov rax, 4
    mov rbx, 1
    cmp byte [rsi], 0x3C
    je big
    ; cmp byte [rsi], 0x1A
    jne little
    big:
        mov rcx, big_endian
        mov rdx, len1
        int 0x80
        jmp end_program
    little:
        mov rcx, little_endian
        mov rdx, len2
        int 0x80
        ; jmp end_program

    end_program:
        mov rbx, 0
        mov rax, 1
        int 0x80