汇编 MUL/IMUL指令

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

_start: ;tell linker entry point

mov al,'3'
sub al, '0'

mov bl, '2'
sub bl, '0'
mul bl
add al, '0'

mov [res], al
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,res
mov edx, 1
mov ebx,1 ;file descriptor (stdout)
mov eax,4 ;system call number (sys_write)
int 0x80 ;call kernel

mov eax,1 ;system call number (sys_exit)
int 0x80 ;call kernel

section .data
msg db "The result is:", 0xA,0xD
len equ $- msg
segment .bss
res resb 1
</code></pre>