【发布时间】：2013-08-07 08:55:52
【问题描述】：
section .data
msg db "Menu: "
msgLen equ $ -msg
msg2 db "[1]Factorial"
msgLen2 equ $ -msg2mov dx, 0
msg3 db "[2]Power"
msgLen3 equ $ -msg3
msg4 db "[3]Exit"
msgLen4 equ $ -msg4
msg5 db "Enter number: "
msgLen5 equ $ -msg5
msg6 db "Enter two numbers: "
msgLen6 equ $ -msg6
line db "", 10
section .bss
choice resb 1
num1 resw 1
quo1 resw 1
quo2 resw 1
quo3 resw 1
quo4 resw 1
quo5 resw 1
rem1 resw 1
rem2 resw 1
rem3 resw 1
rem4 resw 1
rem5 resw 1
section .text
global _start
_start:
do_while:
mov eax, 4
mov ebx, 1
mov ecx, msg
mov edx, msgLen
int 80h
mov eax, 4
mov ebx, 1
mov ecx, line
mov edx, 1
int 80h
mov eax, 4
mov ebx, 1
mov ecx, msg2
mov edx, msgLen2
int 80h
mov eax, 4
mov ebx, 1
mov ecx, line
mov edx, 1
int 80h
mov eax, 4
mov ebx, 1
mov ecx, msg3
mov edx, msgLen3
int 80h
mov eax, 4
mov ebx, 1
mov ecx, line
mov edx, 1
int 80h
mov eax, 4
mov ebx, 1
mov ecx, msg4
mov edx, msgLen4
int 80h
mov eax, 4
mov ebx, 1
mov ecx, line
mov edx, 1
int 80h
mov eax, 3
mov ebx, 0
mov ecx, choice
mov edx, 2
int 80h
sub byte [choice], 30h
cmp byte [choice], 1
je menu1
cmp byte [choice], 2
je power
cmp byte [choice], 3
je exit
jg do_while
jl do_while
menu1:
mov eax, 4
mov ebx, 1
mov ecx, msg5
mov edx, msgLen5
int 80h
mov eax, 3
mov ebx, 0
mov ecx, num1
mov edx, 1
int 80h
sub word [num1], 30h
sub esp, 4
push word [num1]
call fact
pop word [num1] ;40320
mov al, [num1] ;4032
mov ah, 0
mov bl, 10
div bl
mov byte [quo1], al
mov byte [rem1], ah
mov al, [quo1] ;403
mov ah, 0
mov bl, 10
div bl
mov byte [quo2], al
mov byte [rem2], ah
mov al, [quo2] ;40
mov ah, 0
mov bl, 10
div bl
mov byte [quo3], al
mov byte [rem3], ah
mov al, [quo3] ;4
mov ah, 0
mov bl, 10
div bl
mov byte [quo4], al
mov byte [rem4], ah
add word [quo4], 30h
add word [rem4], 30h
add word [rem3], 30h
add word [rem2], 30h
add word [rem1], 30h
mov eax, 4
mov ebx, 1
mov ecx, quo4
mov edx, 1
int 80h
mov eax, 4
mov ebx, 1
mov ecx, rem4
mov edx, 1
int 80h
mov eax, 4
mov ebx, 1
mov ecx, rem3
mov edx, 1
int 80h
mov eax, 4
mov ebx, 1
mov ecx, rem2
mov edx, 1
int 80h
mov eax, 4
mov ebx, 1
mov ecx, rem1
mov edx, 1
int 80h
jmp do_while
fact:
mov ebp, esp
mov cl, [ebp+4]
mov [ebp+6], cl
;conditions
mov ax, [ebp+4]
dec word [ebp+6]
mul word [ebp+6]
mov [ebp+8], al
while:
dec word [ebp+6]
mov al, [ebp+8]
mov dx, 0
mul word [ebp+6]
mov word [ebp+8], ax ;al is byte size
cmp word [ebp+6], 1
jne while
ret 4
power:
mov eax, 1
mov ebx, 0
int 80h
exit:
mov eax, 1
mov ebx, 0
int 80h
我正在计算循环中的阶乘。 5！结果到 120 但 6！结果 208 字节大小仅高达 255，而字大小高达 65,655。 我的代码中应该更改或更正哪些内容？
这是我的代码。不要介意电源，退出标签，cmets。请注意执行阶乘运算的事实标签。
【问题讨论】：
-
您发布的代码看起来像是在进行 16 位乘法运算。是否有什么没有按预期工作？
-
我将编辑我的帖子，向您展示整个代码。