pl/0语言编译器C代码

/* PL/0 编译系统 C 版本头文件 pl0.h */

typedef enum {false, true} bool;

#define norw 13 /* 关键字个数 */

#define txmax 100 /* 名字表容量 */

#define nmax 14 /* number 的最大位数 */

#define al 10 /* 符号的最大长度 */

#define amax 2047 /* 地址上界 */

#define levmax 3 /* 最大允许过程嵌套声明层数[0,levmax] */

writesym, readsym, dosym, callsym, constsym,

varsym, procsym };

#define symnum 32

/* 名字表中的类型 */

enum object { constant, variable, procedur, array};

/* 虚拟机代码 */

enum fct { lit, opr, lod,

sto, cal, inte,

jmp, jpc };

#define fctnum 8

char ch;

enum symbol sym;

char id[al+1];

int num; int cc, ll; int cx; char line[81];

char a[al+1];

struct instruction code[cxmax];

char word[norw][al];

enum symbol wsym[norw]; enum symbol ssym[256];

char mnemonic[fctnum][5];

bool declbegsys[symnum]; bool statbegsys[symnum]; bool facbegsys[symnum];

int level;

int size; };

struct tablestruct table[txmax];

FILE* fin; FILE* fout;

char fname[al];

int err;

#define factordo(a,b,c) if (-1 == factor(a,b,c)) return -1

#define termdo(a,b,c) if (-1 == term(a,b,c)) return -1

#define conditiondo(a,b,c) if (-1 == condition(a,b,c)) return -1

#define statementdo(a,b,c) if (-1 == statement(a,b,c)) return -1

#define constdeclarationdo(a,b,c) if (-1 == constdeclaration(a,b,c)) return -1

#define vardeclarationdo(a,b,c) if (-1 == vardeclaration(a,b,c)) return -1

void error(int n);

int getsym();

int getch();

void init();

int gen(enum fct x, int y, int z);

int block(int lev, int tx, bool * fsys);

void interpret();

int factor(bool * fsys, int * ptx, int lev);

int term(bool * fsys, int * ptx, int lev);

int condition(bool * fsys, int * ptx, int lev);

int term(bool * fsys, int * ptx, int lev);

int expression(bool * fsys, int * ptx, int lev);

int statement(bool * fsys, int * ptx, int lev);

void listcode(int cx0);

int vardeclaration(int * ptx, int lev, int * pdx);

int constdeclaration(int * ptx, int lev, int * pdx);

#include <string.h>

#define stacksize 500

int main()

{ bool nxtlev[symnum];

printf("Input pl/0 file?");

scanf("%s", fname);

fin = fopen(fname, "r");

printf("List symbol table? (Y/N)");

scanf("%s", fname);

tableswitch = (fname[0] == 'y' || fname[0] == 'Y');

fa1 = fopen("fa1.tmp", "w");

fprintf(fa1, "Input pl/0 file?");

fprintf(fa1, "%s\n", fname);

init();

err = 0; cc = cx = ll = 0; ch = ' ';

if(-1 != getsym())

{

fa = fopen("fa.tmp", "w"); fas = fopen("fas.tmp", "w");

return 0;

}

fclose(fa); fclose(fa1); fclose(fas);

if(sym != period)

{ error(9); }

if(err == 0)

{ fa2 = fopen("fa2.tmp","w");

interpret();

fclose(fa2);

}

else

else

printf("\n");

return 0;

}

void init()

{ int i;

strcpy(&(word[0][0]), "begin"); 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; wsym[1] = callsym;

wsym[2] = constsym; wsym[3] = dosym;

strcpy(&(mnemonic[lit][0]), "lit"); strcpy(&(mnemonic[opr][0]), "opr");

strcpy(&(mnemonic[lod][0]), "lod"); strcpy(&(mnemonic[sto][0]), "sto");

strcpy(&(mnemonic[cal][0]), "cal"); strcpy(&(mnemonic[inte][0]), "inte");

strcpy(&(mnemonic[jmp][0]), "jmp"); strcpy(&(mnemonic[jpc][0]), "jpc");

for(i = 0; i < symnum; i++)

{ declbegsys[i] = false; statbegsys[i] = false; facbegsys[i] = false;

}

declbegsys[constsym] = true; declbegsys[varsym] = true; declbegsys[procsym] = true;

facbegsys[ident] = true; facbegsys[number] = true; facbegsys[lparen] = true;

int inset(int e, bool * s)

{ return s[e]; }

int addset(bool * sr, bool * s1, bool * s2, int n)

{ int i;

int subset(bool * sr, bool * s1, bool * s2, int n)

{ int i;

for(i = 0; i < n; i++)

{ sr[i] = s1[i] && !s2[i]; }

return 0;

}

int mulset(bool * sr, bool * s1, bool * s2, int n)

{ int i;

for(i = 0; i < n; i++)

{ sr[i] = s1[i] && s2[i]; }

memset(space, 32, 81);

space[cc - 1] = 0;

printf("****%s!%d\n", space, n);

fprintf(fa1, "****%s!%d\n", space, n);

err++;

}

int getch()

{ if(cc == ll)

{

if(feof(fin))