汇编条件

<pre><code class=”lang-bash”>section .text
global _start ;must be declared for using gcc

_start: ;tell linker entry point
mov ecx, [num1]
cmp ecx, [num2]
jg check_third_num
mov ecx, [num2]

check_third_num:

cmp ecx, [num3]
jg _exit
mov ecx, [num3]

_exit:

mov [largest], ecx
mov ecx,msg
mov edx, len
mov ebx,1 ;file descriptor (stdout)
mov eax,4 ;system call number (sys_write)
int 0x80 ;call kernel

mov ecx,largest
mov edx, 2
mov ebx,1 ;file descriptor (stdout)
mov eax,4 ;system call number (sys_write)
int 0x80 ;call kernel

mov eax, 1
int 80h

section .data

msg db "The largest digit is: ", 0xA,0xD
len equ $- msg
num1 dd '47'
num2 dd '22'
num3 dd '31'

segment .bss
largest resb 2
</code></pre>