编译原理(PL0编译程序源代码)

下载可编辑/*PL/0编译程序（C语言版）*编译和运行环境 ：*VisualC++6.0*WinXP/7*使用方法：*运行后输入 PL/0源程序文件名*回答是否将虚拟机代码写入文件*回答是否将符号表写入文件*执行成功会产生四个文件 （词法分析结果.txt符号表.txt虚拟代码.txt源程序和地址 .txt）*/#include<stdio.h>#include"pl0.h"#include"string"#definestacksize500// 解释执行时使用的栈intmain(){boolnxtlev[symnum];printf("请输入源程序文件名 :");scanf("%s",fname);fin=fopen(fname,"r");// 以只读方式打开 pl0源程序文件cifa=fopen(" 词法分析结果.txt","w");fa1=fopen(" 源程序和地址 .txt","w");// 输出源文件 及各行对应的首地址fprintf(fa1," 输入pl0源程序文件名：");fprintf(fa1,"%s\n",fname);if(fin){printf("是否将虚拟机代码写入文件 ?(Y/N)");//是否输出虚拟机代码scanf("%s",fname);listswitch=(fname[0]=='y'||fname[0]=='Y');printf(" 是否将符号表写入文件 ?(Y/N)");//是否输出符号表scanf("%s",fname);tableswitch=(fname[0]=='y'||fname[0]=='Y');init();//初始化err=0;cc=cx=ll=0;ch='';if(-1!=getsym()){fa=fopen(" 虚拟代码.txt","w");fas=fopen(" 符号表.txt","w");.专业.整理.下载可编辑addset(nxtlev,declbegsys,statbegsys,symnum);nxtlev[period]=true;if(-1==block(0,0,nxtlev)){// 调用编译程序fclose(fa);fclose(fa1);fclose(fas);fclose(fin);return0;}if(sym!=period){error(9);// 结尾丢失了句号}if(err!=0){printf("pl0 源程序出现错误 ，退出编译!!!请从第一个错误处开始修改.\n\n");fprintf(cifa," 源程序出现错误 ，请检查!!!");fprintf(fa1," 源程序出现错误 ，请检查!!!");fprintf(fa," 源程序出现错误 ，请检查!!!");fprintf(fas," 源程序出现错误 ，请检查!!!");}fclose(fa);fclose(fa1);fclose(fas);}fclose(fin);}else{printf("Can'topenfile!\n");}fclose(cifa);//printf("\n");return0;}voidinit(){// 初始化inti;for(i=0;i<=255;i++)ssym[i]=nul;// 设置单字符符号ssym['+']=plus;ssym['-']=minus;ssym['*']=times;ssym['/']=slash;ssym['(']=lparen;.专业.整理.下载可编辑ssym[')']=rparen;ssym['=']=eql;ssym[',']=comma;ssym['.']=period;ssym['#']=neq;ssym[';']=semicolon;strcpy(&(word[0][0]),"begin");// 保留字设置，以字母顺序排列 便于折半查找strcpy(&(word[1][0]),"call");strcpy(&(word[2][0]),"const");strcpy(&(word[3][0]),"do");strcpy(&(word[4][0]),"end");strcpy(&(word[5][0]),"if");strcpy(&(word[6][0]),"odd");strcpy(&(word[7][0]),"procedure");strcpy(&(word[8][0]),"read");strcpy(&(word[9][0]),"then");strcpy(&(word[10][0]),"var");strcpy(&(word[11][0]),"while");strcpy(&(word[12][0]),"write");wsym[0]=beginsym;// 设置保留字类别 一字即一类wsym[1]=callsym;wsym[2]=constsym;wsym[3]=dosym;wsym[4]=endsym;wsym[5]=ifsym;wsym[6]=oddsym;wsym[7]=procsym;wsym[8]=readsym;wsym[9]=thensym;wsym[10]=varsym;wsym[11]=whilesym;wsym[12]=writesym;strcpy(&(mnemonic[lit][0]),"lit");// 设置指令名称strcpy(&(mnemonic[opr][0]),"opr");strcpy(&(mnemonic[lod][0]),"lod");strcpy(&(mnemonic[sto][0]),"sto");strcpy(&(mnemonic[cal][0]),"cal");strcpy(&(mnemonic[inte][0]),"int");.专业.整理.下载可编辑strcpy(&(mnemonic[jmp][0]),"jmp");strcpy(&(mnemonic[jpc][0]),"jpc");for(i=0;i<symnum;i++){// 设置符号集declbegsys[i]=false;statbegsys[i]=false;facbegsys[i]=false;}declbegsys[constsym]=true;// 设置声明开始符号集declbegsys[varsym]=true;declbegsys[procsym]=true;statbegsys[beginsym]=true;// 设置语句开始符号集statbegsys[callsym]=true;statbegsys[ifsym]=true;statbegsys[whilesym]=true;facbegsys[ident]=true;// 设置因子开始符号集facbegsys[number]=true;facbegsys[lparen]=true;}//用数组实现集合的集合运算intinset(inte,bool*s){returns[e];}intaddset(bool*sr,bool*s1,bool*s2,intn){inti;for(i=0;i<n;i++)sr[i]=s1[i]||s2[i];return0;}voiderror(intn){// 出错处理，打印出错位置和错误编码charspace[81];memset(space,32,81);space[cc-1]=0;printf("error(%d)",n);fprintf(fa1,"error(%d)",n);switch(n){.专业.整理.下载可编辑case1:printf("\t\t 常量说明中的“=”写成“:=”\n");fprintf(fa1,"\t\t 常量说明中的 “=”写成“:=”\n");break;case2:printf("\t\t 常量说明中的=后应该是数字\n");fprintf(fa1,"\t\t 常量说明中的 =后应该是数字\n");break;case3:printf("\t\t 常量说明符中的表示符应该是 =\n");fprintf(fa1,"\t\t 常量说明符中的表示符应该是 =\n");break;case4:printf("\t\tconst,var,procedure 后应为标识符 \n");fprintf(fa1,"\t\tconst,var,procedure 后应为标识符\n");break;case5:printf("\t\t 漏掉了“,”或“;”\n");fprintf(fa1,"\t\t 漏掉了“,”或“;”\n");break;case6:printf("\t\t 过程说明后的符号不正确 \n");fprintf(fa1,"\t\t 过程说明后的符号不正确 \n");break;case7:printf("\t\t 应是语句开始符 \n");fprintf(fa1,"\t\t 应是语句开始符 \n");break;case8:printf("\t\t 程序体内语句部分的后跟符不正确 \n");fprintf(fa1,"\t\t程序体内语句部分的后跟符不正确\n");break;case9:printf("\t\t 程序结尾丢了句号 “.”\n\n");fprintf(fa1,"\t\t 程序结尾丢了句号 “.”\n");break;case10:printf("\t\t 语句之间漏了“;”\n");.专业.整理.下载可编辑fprintf(fa1,"\t\t 语句之间漏了 “;”\n");break;case11:printf("\t\t 标识符拼写错误或未说明 \n");fprintf(fa1,"\t\t 标识符拼写错误或未说明 \n");break;case12:printf("\t\t 赋值语句中，赋值号左部标识符属性应是变量 \n");fprintf(fa1,"\t\t 赋值语句中，赋值号左部标识符属性应是变量\n");break;case13:printf("\t\t 赋值语句左部标识符后应是复制号 “:=”\n");fprintf(fa1,"\t\t 赋值语句左部标识符后应是复制号 “:=”\n");break;case14:printf("\t\tcall 后应为标识符 \n");fprintf(fa1,"\t\tcall 后应为标识符 \n");break;case15:printf("\t\tcall 后标识符属性应为过程 \n");fprintf(fa1,"\t\tcall 后标识符属性应为过程 \n");break;case16:printf("\t\t 条件语句中丢了 then\n");fprintf(fa1,"\t\t 条件语句中丢了 then\n");break;case17:printf("\t\t 丢了“end”或“;”\n");fprintf(fa1,"\t\t 丢了“end”或“;”\n");break;case18:printf("\t\twhile 型循环语句中丢了 “do”\n");fprintf(fa1,"\t\twhile 型循环语句中丢了 “do”\n");break;case19:printf("\t\t 语句后的符号不正确 \n");fprintf(fa1,"\t\t 语句后的符号不正确 \n");.专业.整理.下载可编辑break;case20:printf("\t\t 应为关系运算符 \n");fprintf(fa1,"\t\t 应为关系运算符 \n");break;case21:printf("\t\t 表达式内标示符属性不能是过程 \n");fprintf(fa1,"\t\t 表达式内标示符属性不能是过程 \n");break;case22:printf("\t\t 表达式漏掉了右括号 \n");fprintf(fa1,"\t\t 表达式漏掉了右括号 \n");break;case23:printf("\t\t 因子后的非法符号 \n");fprintf(fa1,"\t\t 因子后的非法符号 \n");break;case24:printf("\t\t 表达式的开始符不能是此符号 \n");fprintf(fa1,"\t\t 表达式的开始符不能是此符号 \n");break;case25:printf("\t\t 标识符越界\n");fprintf(fa1,"\t\t 标识符越界\n");break;case26:printf("\t\t 非法字符\n");fprintf(fa1,"\t\t 非法字符\n");break;case31:printf("\t\t 数越界\n");fprintf(fa1,"\t\t 数越界\n");break;case32:printf("\t\tread 语句括号中的标识符不是变量 \n");fprintf(fa1,"\t\tread语句括号中的标识符不是变量\n");break;case33:.专业.整理.下载可编辑printf("\t\twrite() 或read()中应为完整表达式 \n");fprintf(fa1,"\t\twrite() 或read()中应为完整表达式 \n");break;default:printf("\t\t 出现未知错误 \n");fprintf(fa1,"\t\t 出现未知错误 \n");}err++;}漏掉空格，读取一个字符，每次读一行，存入line缓冲区，line被getsym取空后再读一行，被函数getsym调用intgetch(){if(cc==ll){if(feof(fin)){printf("programincomplete");return-1;}ll=0;cc=0;printf("\n%d",cx);fprintf(fa1,"\n%d",cx);ch='';while(ch!=10){if(EOF==fscanf(fin,"%c",&ch)){line[ll]=0;break;}printf("%c",ch);fprintf(fa1,"%c",ch);line[ll]=ch;ll++;}fprintf(cifa,"\n");}ch=line[cc];cc++;return0;}intgetsym(){// 词法分析inti,j,k,l;.专业.整理.下载可编辑while(ch==''||ch==10||ch==9)// 忽略空格 换行TABgetchdo;if(ch>='a'&&ch<='z'){// 以字母开头的为保留字或者标识符k=0,l=1;do{if(k<al){//al 为标识符或保留字最大长度a[k]=ch;k++;}if(k==al&&l==1){error(25);l=0;}getchdo;}while(ch>='a'&&ch<='z'||ch>='0'&&ch<='9');a[k]=0;// 末尾存零strcpy(id,a);i=0;j=norw-1;do{//开始折半查找k=(i+j)/2;if(strcmp(id,word[k])<=0){j=k-1;}if(strcmp(id,word[k])>=0){i=k+1;}}while(i<=j);if(i-1>j){// 找到即为保留字sym=wsym[k];fprintf(cifa,"%s\t\t%ssym\n",id,id);//printf("%s\t\t%ssym\n",id,id);}else{//否则为标识符或数字sym=ident;fprintf(cifa,"%s\t\tident\n",id);//printf("%s\t\tident\n",id);}}else{.专业.整理.下载可编辑if(ch>='0'&&ch<='9'){k=0;num=0;sym=number;do{num=10*num+ch-'0';// 数字的数位处理k++;getchdo;}while(ch>='0'&&ch<='9');k--;if(k>nmax){// 数字的长度限制fprintf(cifa,"0\t\tnumber\n");num=0;error(31);}elsefprintf(cifa,"%d\t\tnumber\n",num);//printf("%d\t\tnumber\n",num);}else{if(ch==':'){//检测赋值符号，:只能和=匹配，否则不能识别getchdo;if(ch=='='){sym=becomes;fprintf(cifa,":=\t\tbecomes\n");getchdo;}else{sym=nul;}}else{if(ch=='<'){getchdo;if(ch=='='){sym=leq;// 小于等于fprintf(cifa,"<=\t\tleq\n");getchdo;}else{sym=lss;//小于fprintf(cifa,"<\t\tlss\n");}.专业.整理.下载可编辑}else{if(ch=='>'){getchdo;if(ch=='='){sym=geq;// 大于等于fprintf(cifa,">=\t\tgeq\n");getchdo;}else{sym=gtr;// 大于fprintf(cifa,">\t\tgtr\n");}}else{sym=ssym[ch];// 不满足上述条件时 按单字//符处理switch(ch){case'+':fprintf(cifa,"%c\t\tplus\n",ch);break;case'-':fprintf(cifa,"%c\t\tminus\n",ch);break;case'*':fprintf(cifa,"%c\t\ttimes\n",ch);break;case'/':fprintf(cifa,"%c\t\tslash\n",ch);break;case'(':fprintf(cifa,"%c\t\tlparen\n",ch);break;case')':fprintf(cifa,"%c\t\trparen\n",ch);break;case'=':fprintf(cifa,"%c\t\teql\n",ch);break;case',':fprintf(cifa,"%c\t\tcomma\n",ch);.专业.整理.下载可编辑break;case'#':fprintf(cifa,"%c\t\tneq\n",ch);break;case';':fprintf(cifa,"%c\t\tsemicolon\n",ch);break;case'.':break;default:error(26);}if(sym!=period){// 判断是否结束getchdo;}else{printf("\n");fprintf(cifa,".\t\tperiod\n");}}}}}}return0;}生成目标代码//目标代码的功能码，层差和位移量intgen(enumfctx,inty,intz){if(cx>=cxmax){// 如果目标代码索引过大 ，报错printf("Programtoolong");return-1;}code[cx].f=x;code[cx].l=y;code[cx].a=z;cx++;return0;}测试字符串.专业.整理.下载可编辑inttest(bool*s1,bool*s2,intn){if(!inset(sym,s1)){// 测试sym是否属于 s1，不属于则报错 nerror(n);while((!inset(sym,s1))&&(!inset(sym,s2))){// 检测不通过时 ，不停获得符号 ，直到它属于需要或补救的集合getsymdo;}}return0;}编译程序主体//lev：当前分程序所在层，tx:名字表当前尾指针fsys：当前模块后跟符号集合intblock(intlev,inttx,bool*fsys){inti;intdx;// 名字分配到的相对地址inttx0;// 保留初始 txintcx0;// 保留初始 cxboolnxtlev[symnum];dx=3;//相对地址从 3开始，前3个单元即 0、1、2单元分别为 SL:静态链；//DL：动态链；RA：返回地址tx0=tx;// 记录本层的初始位置table[tx].adr=cx;gendo(jmp,0,0);if(lev>levmax){// 层数超过 3error(32);}do{if(sym==constsym){// 收到常量声明printf("该语句为常量定义语句 \n");getsymdo;do{constdeclarationdo(&tx,lev,&dx);// 常量声明处理，dx会改变所以使用指针while(sym==comma){// 处理一次多常量定义getsymdo;constdeclarationdo(&tx,lev,&dx);}if(sym==semicolon){// 常量声明处理结束.专业.整理.下载可编辑getsymdo;}else{error(5);// 漏掉了逗号或者分号 （一般是分号）}}while(sym==ident);}if(sym==varsym){// 收到变量声明printf("该语句为变量声明语句 \n");getsymdo;do{vardeclarationdo(&tx,lev,&dx);// 变量声明处理while(sym==comma){// 处理一次多变量定义getsymdo;vardeclarationdo(&tx,lev,&dx);}if(sym==semicolon){// 变量声明处理结束getsymdo;}else{error(5);// 漏掉逗号或者分号}}while(sym==ident);}while(sym==procsym){// 收到过程声明printf("该语句为过程声明语句 \n");getsymdo;if(sym==ident){enter(procedur,&tx,lev,&dx);// 记录过程名getsymdo;}else{error(4);// 过程声明后应为标识符}if(sym==semicolon){getsymdo;}else{error(5);// 漏掉了分号}memcpy(nxtlev,fsys,sizeof(bool)*symnum);nxtlev[semicolon]=true;.专业.整理.下载可编辑if(-1==block(lev+1,tx,nxtlev)){return-1;}if(sym==semicolon){getsymdo;memcpy(nxtlev,statbegsys,sizeof(bool)*symnum);nxtlev[ident]=true;nxtlev[procsym]=true;testdo(nxtlev,fsys,6);}else{error(5);}}memcpy(nxtlev,statbegsys,sizeof(bool)*symnum);nxtlev[ident]=true;nxtlev[period]=true;testdo(nxtlev,declbegsys,7);}while(inset(sym,declbegsys));// 直到没有声明符号code[table[tx0].adr].a=cx;// 开始生成当前过程代码table[tx0].adr=cx;// 当前过程代码地址table[tx0].size=dx;cx0=cx;gendo(inte,0,dx);// 生成分配内存代码if(tableswitch){// 输出符号表if(tx0+1<tx){fprintf(fas,"TABLE:\n");//printf("NULL\n");}for(i=tx0+1;i<=tx;i++){switch(table[i].kind){caseconstant:fprintf(fas,"%dconst%s",i,table[i].name);fprintf(fas,"val=%d\n",table[i].val);break;casevariable:fprintf(fas,"%dvar%s",i,table[i].name);fprintf(fas,"lev=%daddr=%d\n",table[i].level,table[i].adr);break;caseprocedur:.专业.整理.下载可编辑fprintf(fas,"%dproc%s",i,table[i].name);fprintf(fas,"lev=%daddr=%dsize=%d\n",table[i].level,table[i].adr,table[i].size);break;}}}memcpy(nxtlev,fsys,sizeof(bool)*symnum);// 每个后跟符号集和都包含上层后跟符号集和，以便补救nxtlev[semicolon]=true;nxtlev[endsym]=true;statementdo(nxtlev,&tx,lev);gendo(opr,0,0);//每个过程出口都要使用的释放数据指令memset(nxtlev,0,sizeof(bool)*symnum);// 分程序没有补救集合testdo(fsys,nxtlev,8);// 检测后跟符号集的正确性listcode(cx0);// 输出代码return0;}//k:constvarprocedure//ptx:符号表尾的指针//pdx:dx 为当前应分配变量的相对地址//lev:符号名字所在的层次 //往符号表中添加voidenter(enumobjectk,int*ptx,intlev,int*pdx){(*ptx)++;strcpy(table[(*ptx)].name,id);table[(*ptx)].kind=k;switch(k){caseconstant:if(num>amax){error(31);num=0;}table[(*ptx)].val=num;break;casevariable:table[(*ptx)].level=lev;table[(*ptx)].adr=(*pdx);(*pdx)++;.专业.整理.下载可编辑break;caseprocedur:table[(*ptx)].level=lev;break;}}寻找符号在符号表中的地址intposition(char*idt,inttx){inti;strcpy(table[0].name,idt);i=tx;//符号表尾while(strcmp(table[i].name,idt)!=0){i--;}returni;}常量声明处理intconstdeclaration(int*ptx,intlev,int*pdx){if(sym==ident){getsymdo;if(sym==eql||sym==becomes){if(sym==becomes){error(1);}getsymdo;if(sym==number){enter(constant,ptx,lev,pdx);getsymdo;}else{error(2);}}else{error(3);}}else{error(4);}return0;}变量声明处理.专业.整理.下载可编辑intvardeclaration(int*ptx,intlev,int*pdx){if(sym==ident){enter(variable,ptx,lev,pdx);getsymdo;}else{error(4);}return0;}输出目标代码清单voidlistcode(intcx0){inti;if(listswitch){for(i=cx0;i<cx;i++){fprintf(fa,"%d%s%d%d\n",i,mnemonic[code[i].f],code[i].l,code[i],a);}}}语句处理intstatement(bool*fsys,int*ptx,intlev){inti,cx1,cx2;boolnxtlev[symnum];if(sym==ident){i=position(id,*ptx);if(i==0){error(11);}else{if(table[i].kind!=variable){error(12);i=0;}else{getsymdo;if(sym==becomes){getsymdo;printf("该语句为赋值语句 。\n");}else{error(13);.专业.整理.下载可编辑}memcpy(nxtlev,fsys,sizeof(bool)*symnum);expressiondo(nxtlev,ptx,lev);if(i!=0){gendo(sto,lev-table[i].level,table[i].adr);}}}//if(i==0)}else{//保留字匹配if(sym==readsym){printf("该语句为读语句 \n");getsymdo;if(sym!=lparen){error(34);}else{do{getsymdo;if(sym==ident){i=position(id,*ptx);}else{i=0;}if(i==0){error(35);}else{gendo(opr,0,16);gendo(sto,lev-table[i].level,table[i].adr);}getsymdo;}while(sym==comma);}if(sym!=rparen){error(33);while(!inset(sym,fsys)){getsymdo;}}else{.专业.整理.下载可编辑getsymdo;}}else{if(sym==writesym){printf("该语句为写语句 \n");getsymdo;if(sym==lparen){do{getsymdo;memcpy(nxtlev,fsys,sizeof(bool)*symnum);nxtlev[rparen]=true;nxtlev[comma]=true;expressiondo(nxtlev,ptx,lev);gendo(opr,0,14);}while(sym==comma);if(sym!=rparen){error(33);}else{getsymdo;}}gendo(opr,0,15);}else{if(sym==callsym){printf("该语句为调用语句 \n");getsymdo;if(sym!=ident){error(14);}else{i=position(id,*ptx);if(i==0){error(11);}else{if(table[i].kind==procedur){gendo(cal,lev-table[i].level,table[i].adr);}else{error(15);}}getsymdo; }.专业.整理.下载可编辑}else{if(sym==ifsym){printf("该语句为if条件语句\n");getsymdo;memcpy(nxtlev,fsys,sizeof(bool)*symnum);nxtlev[rparen]=true;nxtlev[comma]=true;conditiondo(nxtlev,ptx,lev);if(sym==thensym){getsymdo;}else{error(16);}cx1=cx;gendo(jpc,0,0);statementdo(fsys,ptx,lev);code[cx1].a=cx;}else{if(sym==beginsym){getsymdo;memcpy(nxtlev,fsys,sizeof(bool)*symnum);nxtlev[rparen]=true;nxtlev[comma]=true;statementdo(nxtlev,ptx,lev);while(inset(sym,statbegsys)||sym==semicolon){if(sym==semicolon){getsymdo;}else{error(10);}statementdo(nxtlev,ptx,lev);}if(sym==endsym){getsymdo;}else{error(17);}}else{.专业.整理.下载可编辑if(sym==whilesym){printf("该语句为 while循环语句\n");cx1=cx;getsymdo;memcpy(nxtlev,fsys,sizeof(bool)*symnum);nxtlev[dosym]=true;conditiondo(nxtlev,ptx,lev);cx2=cx;gendo(jpc,0,0);if(sym==dosym){getsymdo;}else{error(18);}statementdo(fsys,ptx,lev);gendo(jmp,0,cx1);code[cx2].a=cx;}else{memset(nxtlev,0,sizeof(bool)*symnum);testdo(fsys,nxtlev,19);}}}}}}}return0;}intexpression(bool*fsys,int*ptx,intlev){enumsymboladdop;boolnxtlev[symnum];if(sym==plus||sym==minus){addop=sym;getsymdo;memcpy(nxtlev,fsys,sizeof(bool)*symnum);nxtlev[plus]=true;nxtlev[minus]=true;termdo(fsys,ptx,lev);.专业.整理.下载可编辑if(addop==minus)gendo(opr,0,1);}else{memcpy(nxtlev,fsys,sizeof(bool)*symnum);nxtlev[plus]=true;nxtlev[minus]=true;termdo(fsys,ptx,lev);}while(sym==plus||sym==minus){addop=sym;getsymdo;memcpy(nxtlev,fsys,sizeof(bool)*symnum);nxtlev[plus]=true;nxtlev[minus]=true;termdo(nxtlev,ptx,lev);if(addop==plus){gendo(opr,0,2);}else{gendo(opr,0,3);}}return0;}intterm(bool*fsys,int*ptx,intlev){enumsymbolmulop;boolnxtlev[symnum];memcpy(nxtlev,fsys,sizeof(bool)*symnum);nxtlev[times]=true;nxtlev[slash]=true;factordo(nxtlev,ptx,lev);while(sym==times||sym==slash){mulop=sym;getsymdo;factordo(nxtlev,ptx,lev);if(mulop==times){gendo(opr,0,4);}else{gendo(opr,0,5);}.专业.整理.下载可编辑}return0;}intfactor(bool*fsys,int*ptx,intlev){inti;boolnxtlev[symnum];testdo(facbegsys,fsys,24);while(inset(sym,facbegsys)){if(sym==ident){i=position(id,*ptx);if(i==0){error(11);}else{switch(table[i].kind){caseconstant:gendo(lit,0,table[i].val);break;casevariable:gendo(lod,lev-table[i].level,table[i].adr);break;caseprocedur:error(21);break;}}getsymdo;}else{if(sym==number){if(num>amax){error(31);num=0;}gendo(lit,0,num);getsymdo;}else{if(sym==lparen){getsymdo;memcpy(nxtlev,fsys,sizeof(bool)*symnum);nxtlev[rparen]=true;expressiondo(nxtlev,ptx,lev);if(sym==rparen){.专业.整理.下载可编辑getsymdo;}else{error(22);}}testdo(fsys,facbegsys,23);}}}return0;}intcondition(bool*fsys,int*ptx,intlev){enumsymbolrelop;boolnxtlev[symnum];if(sym==oddsym){getsymdo;expressiondo(fsys,ptx,lev);gendo(opr,0,6);}else{memcpy(nxtlev,fsys,sizeof(bool)*symnum);nxtlev[eql]=true;nxtlev[neq]=true;nxtlev[lss]=true;nxtlev[leq]=true;nxtlev[gtr]=true;nxtlev[geq]=true;expressiondo(nxtlev,ptx,lev);if(sym!=eql&&sym!=neq&&sym!=lss&&sym!=leq&&sym!=gtr&&sym!=geq){error(20);}else{relop=sym;getsymdo;expressiondo(fsys,ptx,lev);switch(relop){caseeql:gendo(opr,0,8);break;caseneq:gendo(opr,0,9);break;.专业.整理.下载可编辑caselss:gendo(opr,0,10);break;casegeq:gendo(opr,0,11);break;casegtr:gendo(opr,0,12);break;caseleq:gendo(opr,0,13);break;}}}return0;}//pl0 头文件#definenorw13#definetxmax100#definenmax14#defineal10#defineamax2047#definelevmax3#definecxmax200enumsymbol{nul,ident,number,plus,minus,times,slash,oddsym,eql,neq,lss,leq,gtr,geq,lparen,rparen,comma,semicolon,period,becomes,beginsym,endsym,ifsym,thensym,whilesym,writesym,readsym,dosym,callsym,constsym,varsym,procsym,};#definesymnum32enumobject{.专业.整理.constant,variable,procedur,};enumfct{lit, opr,sto, cal,jmp, jpc,};#definefctnum8structinstruction{enumfctf