编译原理实验报告 (7)

#define STARTSYMBOL 'S' //语法部分

#define ID 6 // 变量标识符 #define LT 8 #define LE 9 #define EQ 10 #define NE 11 #define GT 12 #define GE 13 #define IS 14 #define ADD 15 #define SUB 16 #define MUL 17 #define DIV 18 #define LETTER 20 #define DIGIT 21 #define POINT 22 #define OTHER 23 #define POWER 24 #define PLUS 25 #define MINUS 26

#define UFCON 27 //在这用来表示无符号浮点数代指FCON #define ClassF 200 #define EndState -1

/**********************用于无符号数标识***************/ #define LP 28 // ( #define RP 29 // ) #define EOI 30 // #

char TOKEN[20]; struct RetainWord { };

int n; char Word[7]; {1,\}, {2,\}, {3,\}, {4,\}, {5,\},

// + // - // * // /

//词法部分

#define UINT 7//用来表示无符号整数代指ICON

/**********************用于字符串标识*******************/

}rw[5]={

/******************字符串全局变量********************/

int w,n,p,e,d;//w尾数累加器，n十进制小数位数计数器，p指数累加器，e指数符号，d存当前数值 int Class; //Used to indicate class of the word int x=0;

int l=0; //列标识 int lf=0; //标识符首位置 int r=0; //行标 int ICON; float FCON;

static int CurrentState; //Used to present current state, the initial value:0

int stack[MAXSTACK]; /* a[ ] is input line */ char a[MAXINPUT];

int IsHigherThan (int, int); /* prioriy detection */ int IsLowerThan (int, int); /* prioriy detection */ int IsEqualTo (int, int); /* prioriy detectin */ int Reduce (int begin, int end, int len);

int table[11][11]={

//语法部分算符优先矩阵，为>,-1为< 0为=;其他为错误类型 //+,-,*,/,(,),ID,UCON,:=,#,N //- //* //,/ //) //ID //UCON

{1,1,-1,-1,-1,1,-1,-1,6,1,1},

{1,1,-1,-1,-1,1,-1,-1,6,1,1}, {1,1,1,1,-1,1,-1,-1,6,1,1}, {1,1,1,1,-1,1,-1,-1,6,1,1}, {1,1,1,1,5,1,5,5,6,1,5}, {1,1,1,1,5,1,5,5,1,1,5},

void coor(char ch1) //词法部分 { }

if(ch1==10){

r++;l=0;} l+=7; l++; else if(ch1==9) else

{1,1,1,1,5,1,5,5,6,1,5},

{-1,-1,-1,-1,-1,0,-1,-1,6,1,-1}, //(

{-1,-1,-1,-1,-1,7,-1,-1,7,1,-1},//:=

{-1,-1,-1,-1,-1,7,-1,-1,-1,-1,-1},//# {1,1,1,1,5,1,5,5,-1,1,0}}; //N

/******************无符号数全局变量********************/ int lookup(char *a) {

for(int i=0;i<5;i++)

}

if(strcmp(rw[i].Word,a)==0)

return(rw[i].n); //保留字减去字符数组如果值为就返回保留字类型

return(0);

int report_error(int sk){ }

/******************字符串的函数********************/ int GetChar (FILE *fp) { }

int EXCUTE (int state, int symbol)//state当前状态symbol扫视字符 {

int c; lf=l; c=fgetc(fp); coor(c);

if(isdigit(c)) { }

if (c=='.')

return POINT; return POWER; return PLUS; return MINUS; if (c=='E'||c=='e') if (c=='+') if (c=='-') return OTHER;

d=c-'0'; return DIGIT;

printf(\第%d行，第%d列，出现\,r+1,lf+1); switch (sk) {

case 1:printf(\出现非法无符号浮点数！！词法错误，错误类型%d。\\n\,sk);break; case 2:printf(\出现无法识别符号！！词法错误，错误类型%d。\\n\,sk);break; case 3:printf(\出现无法识别字符！！词法错误，错误类型%d。\\n\,sk);break; case 4:printf(\出现两符号相邻，之间缺少数字或标识符！！语法错误，错误类型%d。case 5:printf(\缺少运算符！！语法错误，错误类型%d。\\n\,sk);break;

case 6:printf(\出现赋值符号前不是标识符的错误！！语法错误，错误类型%d。\\n\,sk);break; case 7:printf(\出现非文法定义的句型！！语法错误，错误类型%d。\\n\,sk);break; case 8:printf(\缺少语句终结符号“#”！！语法错误，错误类型%d。\\n\,sk);break; } return 0;

\\n\,sk);break;

switch (state) { case 0:

switch (symbol) {

case DIGIT: n=0;p=0;e=1;w=d;CurrentState=1;break; case POINT: w=0;n=0;p=0;e=1;CurrentState=3;break; default: report_error(1);Class=0;CurrentState=EndState; }

break; {

case DIGIT: w=w*10+d;break;

//CurrentState=1

case POINT: CurrentState=2;break; case POWER: CurrentState=4;break;

default: ICON=w;Class=UINT;CurrentState=EndState; }

case 1:switch (symbol)

break;

{

case DIGIT: n++;w=w*10+d;break; case POWER: CurrentState=4;x=1;break; default: if(n>0){ }

Class=ClassF;

FCON=(float)w*pow(10,e*p-n); }

CurrentState=EndState;

}

report_error(1);Class=0; else{

case 2:switch (symbol)

break;

{

case DIGIT: n++;w=w*10+d;CurrentState=2;break; default: report_error(2); }

Class=0;CurrentState=EndState;

case 3:switch (symbol)

break;

{

case DIGIT: p=p*10+d;CurrentState=6;break; case MINUS: e=-1;CurrentState=5;break; case PLUS: CurrentState=5;break;

case 4:switch (symbol)

}

}

default:report_error(1);Class=0;CurrentState=EndState; }

break;

{

case DIGIT: p=p*10+d;CurrentState=6;break; default: report_error(1);Class=0; }

CurrentState=EndState;

case 5:switch (symbol)

break;

{

case DIGIT:p=p*10+d;break;

default: FCON=(float)w*pow(10,e*p-n);Class=ClassF;CurrentState=EndState; }

case 6:switch (symbol)

break;

return CurrentState;

int LEX (FILE *fp) { }

//*****************浮点数部分代码*********

int out(int n,char *p) {

int t=0; switch(n) {

case 1:printf(\,rw[n-1].Word);t=1;break; case 2:printf(\,rw[n-1].Word);t=2;break; case 3:printf(\,rw[n-1].Word);t=3;break; case 4:printf(\,rw[n-1].Word);t=4;break; case 5:printf(\,rw[n-1].Word);t=5;break; case 6:printf(\,p);t=6;break; case 7:printf(\,ICON);t=7;break; int ch;

CurrentState=0;

while (CurrentState!=EndState){ }

return Class;

ch=GetChar(fp);

EXCUTE (CurrentState,ch);