SINGLE PASS MACRO PROCESSOR

AIM:

To write a C program to implement the macroprocesso.

ALGORITHM:

Step 1: Start the program.

Step 2: Get the statement from input file.

Step 3: From the line read, check if the opcode is the directive “MACRO” if so then the number of macro must be incremented.

Step 4: Repeat step-1 and 2 until end of the file is encountered.

Step 5: Open number of files in write mode. These files will later hold the body of macro.

Step 6: If the “MACRO” enter macro name in operand field.

Step 7: Write all remaining lines directly.

Step 8: Stop the program.

SOURCE CODE:

#include<stdio.h>

#include<conio.h>

#include<string.h>

struct macrodef

{

char label[10],opcode[10],operand[10];

}mdef[20];

struct input

{

char label[10],opcode[10],operand[10];

}ip[20];

struct output

{

char label[10],opcode[10],operand[10];

}op[20];

char mname[10];

char arg[10][10];

void main()

{

int i=0,j=0,k,n,o=1,q,w,t;

int x,y,p,l,flag;

char temp[10][10];

clrscr();

printf("\nEnter the macro name:");

scanf("%s",mname);

printf("\nEnter the no. of arguments:");

scanf("%d",&n);

printf("\nEnter the arguments:");

for(k=1;k<=n;k++)

{

scanf("%s",arg[k]);

}

printf("\nEnter the macro definition");

do

{

i++;

printf("\nEnter the \nLabel\tOpcode\tOperand\n");

scanf("%s\t%s\t%s",mdef[i].label,mdef[i].opcode,mdef[i].operand);

}

while(strcmp(mdef[i].opcode,"MEND")!=0);

printf("\nEnter the input program\n");

do

{

j++;

printf("\nEnter the \nLabel\tOpcode\tOperand\n");

scanf("%s\t%s\t%s",ip[j].label,ip[j].opcode,ip[j].operand);

}

while(strcmp(ip[j].opcode,"END")!=0);

for(k=1;k<=j;k++)

{

if(strcmp(ip[k].opcode,mname)!=0)

{

strcpy(op[o].label,ip[k].label);

strcpy(op[o].opcode,ip[k].opcode);

strcpy(op[o].operand,ip[k].operand);

o++;

}

else

{

x=0;

l=strlen(ip[k].operand);

y=1;

while(x<1)

{

p=0;

while((ip[k].operand[x]!=',')&&(ip[k].operand[x]!='\0'))

{

temp[y][p]=ip[k].operand[x];

p++;

x++;

}

temp[y][p]='\0';

y++;

x++;

}

for(w=1;w<i;w++)

{

flag=0;

for(t=1;t<=n;t++)

{

if(strcmp(mdef[w].operand,arg[t])==0)

{

flag=1;

break;

}

}

if(flag==1)

{

strcpy(op[o].label,mdef[w].label);

strcpy(op[o].opcode,mdef[w].opcode);

strcpy(op[o].operand,temp[t]);

}

o++;

}

}

}

printf("Macro Definition\n");

printf("%s\tMacro",mname);

for(q=1;q<n;q++)

{

printf("&%s",arg[q]);

}

printf("&%s\n",arg[n]);

for(q=1;q<i;q++)

{

printf("%s\t%s\t%s\n",mdef[q].label,mdef[q].opcode,mdef[q].operand);

}

printf("Input program\n");

for(q=1;q<=j;q++)

{

printf("%s\t%s\t%s\n",ip[q].label,ip[q].opcode,ip[q].operand);

}

printf("Output Program\n");

for(q=1;q<o;q++)

{

printf("%s\t%s\t%s\n",op[q].label,op[q].opcode,op[q].operand);

}

getch();

}

OUTPUT:

Enter the macro name:ADD

Enter the no. of arguments:1

Enter the arguments:X

Enter the macro definition

Enter the

Label   Opcode  Operand

-       LDA     X

Enter the

Label   Opcode  Operand

-       MEND    -

Enter the input program

Enter the

Label   Opcode  Operand

-       ADD     A

Enter the

Label   Opcode  Operand

-       END     -

Macro Definition

ADD     Macro&X

-       LDA     X

Input program

-       ADD     A

-       END     -

Output Program

-       LDA     A

-       END     -

Result

Thus above program executed and output verified.