汇编语言008（条件跳转应用、loopnz条件循环指令使用、loopz条件循环指令使用、if语句编写汇编时、while语句编写汇编时、循环内的if语句嵌套）

1&＃xff1a; 条件跳转应用&＃xff0c;三个数中最小数

.386
.model flat,stdcall.stack 4096
ExitProcess PROTO,dwExitCode:DWORD.data
V1 WORD 1
V2 WORD 2
V3 WORD 3.code
main PROCmov ax,V1 ;假设V1是最小值cmp ax,V2 ;如果AX小于等于V2jbe L1mov ax,v2
L1:cmp ax,V3jbe L2mov ax,V3
L2:INVOKE ExitProcess,0
main ENDP
END main


2&＃xff1a; 条件跳转应用&＃xff0c;循环直到按下按键

.386
.model flat,stdcallinclude Irvine32.inc.stack 4096
ExitProcess PROTO,dwExitCode:DWORD.data
char BYTE ?.code
main PROCL1:mov eax,10call Delay ;10毫秒的延迟call ReadKey ;检查按键jz L1 ;如果没有按键就循环mov char,AL ;保存字符INVOKE ExitProcess,0
main ENDP
END main


3&＃xff1a; 条件跳转应用&＃xff0c;顺序搜索数组

.386
.model flat,stdcallinclude Irvine32.inc.stack 4096
ExitProcess PROTO,dwExitCode:DWORD.data
intArray SWORD 0,0,0,0,1,20,35,-12,66,4,0
noneMsg BYTE "A non-zero value was not found",0.code
main PROCmov ebx,OFFSET intArraymov ecx,LENGTHOF intArray
L1:cmp WORD PTR[ebx],0jnz foundadd ebx,2loop L1jmp notFound
found:movsx eax,WORD PTR[ebx]call WriteIntjmp quit
notFound:mov edx,OFFSET noneMsgcall WriteString
quit:call CrlfINVOKE ExitProcess,0
main ENDP
END main


4&＃xff1a; 条件跳转应用&＃xff0c;简单字符串加密

.386
.model flat,stdcall.stack 4096
ExitProcess PROTO,dwExitCode:DWORDinclude Irvine32.incKEY &＃61; 239
BUFMAX &＃61; 128.data
sPrompt BYTE "Enter the plain text:",0
sEncrypt BYTE "Cipher text: ",0
sDecrypt BYTE "Decrypted: ",0
buffer BYTE BUFMAX&＃43;1 DUP(0)
bufSize DWORD ?.code
main PROCcall InputTheStringcall TranslateBuffermov edx,OFFSET sEncryptcall DisplayMessagecall TranslateBuffermov edx,OFFSET sDecryptcall DisplayMessageINVOKE ExitProcess,0
main ENDP;提示用户输入一个纯文本字符串
;保存字符串和它的长度
;接收&＃xff1a;无
;返回&＃xff1a;无
InputTheString PROCpushadmov edx,OFFSET sPromptcall WriteStringmov ecx,BUFMAXmov edx,OFFSET buffercall ReadStringmov bufSize,eaxcall Crlfpopadret
InputTheString ENDP;显示加密或解密消息
;接收&＃xff1a;EDX指向消息
;返回&＃xff1a;无
DisplayMessage PROCpushadcall WriteStringmov edx,OFFSET buffercall WriteStringcall Crlfcall Crlfpopadret
DisplayMessage ENDP;字符串的每个字符与密钥字节进行异或实现转换
;接收&＃xff1a;无
;返回&＃xff1a;无
TranslateBuffer PROCpushadmov ecx,bufSizemov esi,0
L1:xor buffer[esi],KEYinc esiloop L1popadret
TranslateBuffer ENDP
END main


5&＃xff1a; loopnz 条件循环指令使用&＃xff0c;查找数组第一个非负数

.386
.model flat,stdcall.stack 4096
ExitProcess PROTO,dwExitCode:DWORD.data
array SWORD -3,-6,-1,-10,10,30,40,4
sentinel SWORD 0.code
main PROCmov esi,OFFSET arraymov ecx,LENGTHOF array
L1:test WORD PTR[esi],8000h ;测试符号位pushfd ;标志位入栈add esi,TYPE array ;移动到下一个位置popfdloopnz L1 ;当ZF&＃61;0时继续循环 jnz quit ;没有发现非负数sub esi,TYPE array ;ESI指向数值
quit:INVOKE ExitProcess,0main ENDP
END main


6&＃xff1a; loopz 条件循环指令使用&＃xff0c;查找数组第一个负数

.386
.model flat,stdcall.stack 4096
ExitProcess PROTO,dwExitCode:DWORD.data
array SWORD 3,6,1,10,-10,-30,-40,-4
sentinel SWORD 0.code
main PROCmov esi,OFFSET arraymov ecx,LENGTHOF array
L1:test WORD PTR[esi],8000h ;测试符号位pushfd ;标志位入栈add esi,TYPE array ;移动到下一个位置popfdloopz L1 ;当ZF&＃61;1时继续循环 jz quit ;没有发现非负数sub esi,TYPE array ;ESI指向数值
quit:INVOKE ExitProcess,0main ENDP
END main


7&＃xff1a; if语句编写汇编时的情况

.386
.model flat,stdcall.stack 4096
ExitProcess PROTO,dwExitCode:DWORD;if(al > bl) & (bl > cl)
; X &＃61; 1.data
X DWORD ?.code
main PROCINVOKE ExitProcess,0
main ENDPproc_1 PROCcmp al,blja L1jmp nextL1:cmp bl,clja L2jmp nextL2:mov X,1next:
proc_1 ENDP;如果将ja 换成 jbe,代码减少2条
proc_2 PROCcmp al,bljbe nextcmp bl,cljbe nextmov X,1next:proc_2 ENDPEND main


8&＃xff1a; if语句编写汇编时的情况

.386
.model flat,stdcall.stack 4096
ExitProcess PROTO,dwExitCode:DWORD.data
X DWORD ?;if(al > bl) || (bl > cl)
;X &＃61;1.code
main PROCcmp al,blja L1cmp bl,cljbe next
L1: mov X,1
next:INVOKE ExitProcess,0
main ENDP
END main


9&＃xff1a; while语句编写汇编时的情况

.386
.model flat,stdcall.stack 4096
ExitProcess PROTO,dwExitCode:DWORD.data
val1 DWORD 10
val2 DWORD 20;while (val1 < val2)
;{
; val1 &＃43;&＃43;;
; val2 --;
;}.code
main PROCmov eax,val1
beginwhile:cmp eax,val2jnl endwhileinc eaxdec val2jmp beginwhile
endwhile:mov val1,eaxINVOKE ExitProcess,0
main ENDP
END main


10&＃xff1a; 循环内的if语句嵌套

.386
.model flat,stdcall.stack 4096
ExitProcess PROTO,dwExitCode:DWORD.data
sum DWORD 0
sample DWORD 50 ;计算数组所有大于sample的数之和
array DWORD 10,60,20,33,72,89,45,72,18
arraySize &＃61; ($ - array)/TYPE array.code
main PROCmov eax,0mov edx,samplemov esi,0mov ecx,arraySize
L1:cmp esi,ecxjl L2jmp L5
L2:cmp array[esi*4],edxjg L3jmp L4
L3:add eax,array[esi*4]
L4:inc esijmp L1
L5:mov sum,eaxINVOKE ExitProcess,0
main ENDP
END main