Two Pass Assembler

Two Pass Assembler

  #include< stdio.h>
  #include< string.h>
  #include< conio.h>


  void main()
  {
   char *code[9][4]={
   {"PRG1","START","",""},
   {"","USING","*","15"},
   {"","L","",""},
   {"","A","",""},
   {"","ST","",""},
   {"FOUR","DC","F",""},
   {"FIVE","DC","F",""},
   {"TEMP","DS","1F",""},
   {"","END","",""}
   };
   char av[2],avail[15]={'N','N','N','N','N','N','N','N','N','N','N','N','N','N','N'};
   int i,j,k,count[3],lc[9]={0,0,0,0,0,0,0,0,0},loc=0;
   clrscr();
   printf("----------------------------------------------------\n");
   printf("LABEL\t\tOPCODE\n");
   printf("----------------------------------------------------\n\n");
   for(i=0;i< =8;i++)
   {
    for(j=0;j< =3;j++)
    {
     printf("%s\t\t",code[i][j]);
    }
    j=0;
    printf("\n");
   }
   getch();
   printf("-----------------------------------------------------");
   printf("\nVALUES FOR LC : \n\n");
   for(j=0;j< =8;j++)
   {
    if((strcmp(code[j][1],"START")!=0)&&(strcmp(code[j][1],"USING")!=0)&&(strcmp(code[j][1],"L")!=0))
     lc[j]=lc[j-1]+4;
    printf("%d\t",lc[j]);
   }
   printf("\n\nSYMBOL TABLE:\n----------------------------------------------------\n");
   printf("SYMBOL\t\tVALUE\t\tLENGTH\t\tR/A");
   printf("\n----------------------------------------------------\n");

   for(i=0;i< 9;i++)
   {
    if(strcmp(code[i][1],"START")==0)
    {
     printf("%s\t\t%d\t\t%d\t\t%c\n",code[i][0],loc,4,'R');
    }
    else if(strcmp(code[i][0],"")!=0)
    {
     printf("%s\t\t%d\t\t%d\t\t%c\n",code[i][0],loc,4,'R');
     loc=4+loc;
    }
   else if(strcmp(code[i][1],"USING")==0){}
   else
   {
    loc=4+loc;}
   }
   printf("----------------------------------------------------");

   printf("\n\nBASE TABLE:\n-------------------------------------------------------\n");
   printf("REG NO\t\tAVAILIBILITY\tCONTENTS OF BASE TABLE");
   printf("\n-------------------------------------------------------\n");
   for(j=0;j< =8;j++)
   {
    if(strcmp(code[j][1],"USING")!=0)
    {}
    else
    {
     strcpy(av,code[j][3]);
    }
   }
   count[0]=(int)av[0]-48;
   count[1]=(int)av[1]-48;
   count[2]=count[0]*10+count[1];
   avail[count[2]-1]='Y';

   for(k=0;k< 16;k++)
   {
    printf(" %d\t\t %c\n",k,avail[k-1]);
   }

   printf("-------------------------------------------------------\n");
   printf("Continue..??");
   getchar();
   printf("PASS2 TABLE:\n\n");
   printf("LABEL\t\tOP1\t\tLC\t\t");
   printf("\n----------------------------------------------------\n");
   loc=0;
   for(i=0;i< =8;i++)
   {
    for(j=0;j< =3;j++)
    {
     printf("%s\t\t",code[i][j]);
    }
    j=0;
    printf("\n");
   }
   printf("-----------------------------------------------------");

   getch();

  }
  /*
  ----------------------------------------------------
  LABEL OPCODE
  ----------------------------------------------------

  PRG1 START
  USING * 15
  L
  A
  ST
  FOUR DC F
  FIVE DC F
  TEMP DS 1F
  END



  -----------------------------------------------------
  VALUES FOR LC :

  0 0 0 4 8 12 16 20 24

  SYMBOL TABLE:
  ----------------------------------------------------
  SYMBOL VALUE LENGTH R/A
  ----------------------------------------------------

  PRG1 0 4 R
  FOUR 12 4 R
  FIVE 16 4 R
  TEMP 20 4 R


  ----------------------------------------------------

  BASE TABLE:
  -------------------------------------------------------
  REG NO AVAILIBILITY CONTENTS OF BASE TABLE
  -------------------------------------------------------
  0 -----------------------------------
  1 N
  2 N
  3 N
  4 N
  5 N
  6 N
  7 N
  8 N
  9 N
  10 N
  11 N
  12 N
  13 N
  14 N
  15 Y

  -------------------------------------------------------
  Continue..??
  PASS2 TABLE:

  LABEL OP1 LC
  ----------------------------------------------------
  PRG1 START
  USING * 15
  L
  A
  ST
  FOUR DC F
  FIVE DC F
  TEMP DS 1F
  END
  -----------------------------------------------------


  */