6@-第6章-子程序结构汇编语言（清华）

上传人：1*** IP属地：北京上传时间：2023-02-22 格式：PPT 页数：32 大小：426KB 积分：15 举报 版权申诉

已阅读5页，还剩27页未读，继续免费阅读

版权说明：本文档由用户提供并上传，收益归属内容提供方，若内容存在侵权，请进行举报或认领

文档简介

第六章子程序结构汇编语言过程定义伪操作子程序的调用与返回保存与恢复寄存器子程序的参数传送子程序的嵌套与递归主要内容：汇编语言1.过程定义伪操作过程名PROCNEAR

(FAR

)

过程名ENDP（1）NEAR属性：调用程序和子程序在同一代码段中（段内调用）（2）FAR属性：调用程序和子程序不在同一代码段中（段间调用）...汇编语言codesegment

mainprocfar……

callsubr1……retmainendpsubr1procnear……

retsubr1

endpcodeends段内调用segxsegmentsubtprocfar……

retsubt

endp……

callsubt……segxendssegysegment……

callsubt……segyends段间调用汇编语言子程序调用：隐含使用堆栈保存返回地址

call

near

ptr

subp

(1)保存返回地址

(2)转子程序

call

far

ptr

subp

(1)保存返回地址

(2)转子程序子程序返回：ret2.子程序的调用与返回

(SP)→

(IP)(IP)(CS)(SP)→汇编语言3.保存与恢复寄存器subt

procfar

pushaxpushbxpushcxpushdx…………popdxpopcxpopbxpopaxretsubt

endp汇编语言(1)通过寄存器传送参数(2)通过存储器传送参数(3)通过地址表传送参数地址(4)通过堆栈传送参数或参数地址(5)多个模块之间的参数传送4.子程序的参数传送汇编语言例：十进制到十六进制的转换（通过寄存器传送参数）decihexsegment;1016assumecs:decihexmainprocfarpushdssubax,axpushaxrepeat:calldecibin

;102

callcrlf

;回车换行

callbinihex

;216

callcrlf

jmprepeatretmainendp………………;三个子程序decihexendsendmain汇编语言decibinprocnear

mov

bx,0newchar:movah,1

int21hsubal,30h

jlexit

cmpal,9

jgexit

cbw

xchgax,bx

mov

cx,10

mul

xchgax,bxaddbx,ax

jmp

newcharexit:retdecibin

endpbinihexprocnear

mov

ch,4rotate:mov

cl,4

rol

bx,cl

moval,blandal,0fhaddal,30h

cmpal,3ah

printitaddal,7printit:movdl,al

movah,2

int21h

dec

jnzrotateretbinihex

endpcrlfprocnear

movdl,0dh

movah,2

int21h

movdl,0ah

movah,2

int21hretcrlf

endp汇编语言例：十六进制到十进制的转换（通过寄存器传送参数）hexidecsegment;1610assumecs:hexidec

mainprocfarstart:pushdssubax,axpushaxrepeat:callhexibin

;162

callcrlf

callbinidec

;210

callcrlf

jmprepeatretmainendp………………hexidecendsendstart汇编语言hexibinprocnear

mov

bx,0newchar:

movah,1

int21hsubal,30h

jlexit

cmpal,10

jladd_tosubal,27h

cmpal,0ah

jlexit

cmpal,10h

jgeexitadd_to:

mov

cl,4

shl

bx,cl

movah,0addbx,ax

jmp

newcharexit:rethexibin

endpbinidecprocnear

mov

cx,10000d

calldec_div

mov

cx,1000d

calldec_div

mov

cx,100d

calldec_div

mov

cx,10d

calldec_div

mov

cx,1d

calldec_div

retbinidec

endpdec_divprocnear

movax,bx

mov

dx,0divcx

mov

bx,dx

movdl,aladddl,30h

movah,2

int21hretdec_div

endp汇编语言例：累加数组中的元素（通过存储器传送参数）datasegment

ary

dw1,2,3,4,5,6,7,8,9,10countdw10sumdw?dataendscodesegmentmainprocfarassumecs:code,ds:datapushdssubax,axpushax

movax,data

mov

ds,ax

callproaddretmainendp……;proadd子程序codeendsendmainproaddprocnear

pushaxpushcxpushsileasi,ary

mov

cx,count

xorax,axnext:addax,[si]addsi,2loopnext

mov

sum,axpopsipopcxpopaxretproadd

endp汇编语言如果数据段定义如下：datasegment

ary

dw1,2,3,4,5,6,7,8,9,10countdw10sumdw?ary1dw10,20,30,40,50,60,70,80,90,100count1dw10sum1dw?dataends如果直接访问内存变量，那么累加数组ary和数组ary1中的元素不能用同一个子程序

proadd。汇编语言例：累加数组中的元素（通过地址表传送参数地址）datasegment

ary

dw1,2,3,4,5,6,7,8,9,10countdw10sumdw?

tabledw3dup(?)

;地址表dataendscodesegmentmainprocfarassumecs:code,ds:datapushdssubax,axpushax

movax,data

mov

ds,ax

movtable,offsetary

movtable+2,offsetcount

movtable+4,offsetsum

;建立地址表

mov

bx,offsettable

;地址表的地址->bx

callproaddretmainendp

汇编语言

10d

ary

1dcountsumtable0000001400160018000000140016(bx)55dproaddprocnearpushaxpushcxpushsipushdi

mov

si,[bx]

mov

di,[bx+2]

mov

cx,[di]

mov

di,[bx+4]

xorax,axnext:addax,[si]addsi,2loopnext

mov[di],axpopdipopsipopcxpopaxretproadd

endpcodeendsendmain汇编语言stacksegment

dw100dup(?)

toslabelwordstackendsstart:

movax,stack

mov

ss,ax

movsp,offsettospushdssubax,axpushax……通过堆栈传送参数或参数地址：PSPDSESSSCSPSPDSESSSCSstacksegmentstack

dw100dup(?)

toslabelwordstackends汇编语言例：累加数组中的元素（通过堆栈传送参数地址）datasegment

ary

dw1,2,3,4,5,6,7,8,9,10countdw10sumdw?dataendsstacksegment

dw100dup(?)

toslabelwordstackends汇编语言code1segmentmainprocfarassumecs:code1,ds:data,ss:stackstart:

movax,stack

mov

ss,ax

movsp,offsettospushdssubax,axpushax

movax,data

mov

ds,ax

mov

bx,offsetarypushbx

mov

bx,offsetcountpushbx

mov

bx,offsetsumpushbx

callfarptr

proaddretmainendpcode1ends(ip)(cs)0016001400000(ds)

(sp)汇编语言code2segmentassumecs:code2proaddprocfar

pushbp

mov

bp,sppushaxpushcxpushsipushdi

movsi,[bp+0ah]

movdi,[bp+8]

mov

cx,[di]

movdi,[bp+6]code2endsendstart

xorax,axnext:addax,[si]addsi,2loopnext

mov[di],axpopdipopsipopcxpopaxpopbp

ret6proadd

endp(ip)(cs)0016001400000(ds)

(di)(si)(cx)(ax)(sp)(bp)(bp)

(bp)+0ah

(bp)+8

(bp)+6汇编语言结构伪操作STRUC：

定义一种可包含不同类型数据的结构模式格式：结构名

STRUC

字段名1

DB?

字段名2

DW?

字段名3

DD?……

结构名

ENDS

例：学生个人信息

STUDENT_DATA

STRUC

NAMEDB5DUP(?)IDDW0AGEDB?DEPDB10DUP(?)

STUDENT_DATA

ENDS汇编语言例：累加数组中的元素（通过堆栈传送参数地址）code2segmentassumecs:code2

stack_strc

struc

save_bp

dw?

save_cs_ip

dw2dup(?)par3_addrdw?par2_addrdw?par1_addrdw?

stack_strc

endsproaddprocfar…………proadd

endp

code2endsendstart汇编语言proaddprocfarpushbp

mov

bp,sppushaxpushcxpushsipushdi

mov

si,[bp].par1_addr

mov

di,[bp].par2_addr

mov

cx,[di]

mov

di,[bp].par3_addr

xorax,axnext:addax,[si]addsi,2loopnext

mov[di],axpopdipopsipopcxpopaxpopbpret6proadd

endp(ip)(cs)0016001400000(ds)

(di)(si)(cx)(ax)(sp)(bp)(bp)par3_addrpar2_addrpar1_addr汇编语言5.子程序的嵌套与递归子程序的嵌套：主程序

子程序A

子程序B递归子程序：n!……call

proc_A……proc_A

……callproc_B……retproc_B……ret汇编语言例：计算n!framestruc

save_bp

dw?

save_cs_ip

dw2dup(?)ndw?

result_addr

dw?frameendsdatasegmentn_vdw3resultdw?dataendsstacksegment

dw128dup(?)

toslabelwordstackends汇编语言codesegmentmainprocfarassumecs:code,ds:data,ss:stackstart:

movax,stack

mov

ss,ax

movsp,offsettospushdssubax,axpushax

movax,data

mov

ds,ax

mov

bx,offsetresultpushbx

mov

bx,n_vpushbxcallfarptrfactretmainendpcodeends汇编语言code1segmentassumecs:code1factprocfarpushbp

mov

bp,sppushbxpushax

mov

bx,[bp].result_addr

movax,[bp].n

cmpax,0jedonepushbx

decaxpushax

callfarptrfact

mov

bx,[bp].result_addr

movax,[bx]

mul[bp].n

jmpshortreturndone:movax,1return:

mov[bx],axpopaxpopbxpopbpret4factendpcode1ends

(AX)(BX)(BP)CODE中的(IP)CODE中的(CS)

3RESULT的地址第1帧

(AX)(BX)

(BP)CODE1中的(IP)CODE1中的(CS)

2RESULT的地址第2帧