Pass-II of two pass assembler implementation

Problem Statement:-

Implement Pass-II of two pass assembler for pseudo-machine in Java using object oriented features. The output of assignment-1 (intermediate file and symbol table) should be input for this assignment.

You can download source code from this link. ==> SPOS P2_ASM

Assembler Process

Input:-

	(AD,01) (C,100)
	(DL,02) (C,3)
	(IS,04) 1 (S,03)
	(IS,01) 1 (S,04)
	(IS,05) 1 (S,05)
	(AD,04) (S,1)+1
	(IS,010) (S,05)
	(AD,03) (S,6)+1
	(IS,00)
	(DL,01) (C,19)
	(DL,01) (C,17)
	(AD,02)

view raw IC.txt hosted with ❤ by GitHub

	START 100
	A DS 3
	L1 MOVER AREG, B
	ADD AREG, C
	MOVEM AREG, D
	D EQU A+1
	L2 PRINT D
	ORIGIN L2+1
	STOP
	B DC '19
	C DC '17
	END

view raw input.asm hosted with ❤ by GitHub

	1 0
	2 0

view raw POOLTAB.txt hosted with ❤ by GitHub

	1 A 100
	2 L1 103
	3 B 108
	4 C 109
	5 D 101
	6 L2 106

view raw SYBMTAB.txt hosted with ❤ by GitHub

Support Classes:-

	public class TableRow {
	String symbol;
	int address;
	int index;
	public TableRow(String symbol, int address) {
	super();
	this.symbol = symbol;
	this.address = address;
	}
	public TableRow(String symbol, int address,int index) {
	super();
	this.symbol = symbol;
	this.address = address;
	this.index=index;
	}
	public int getIndex() {
	return index;
	}
	public void setIndex(int index) {
	this.index = index;
	}
	public String getSymbol() {
	return symbol;
	}
	public void setSymbol(String symbol) {
	this.symbol = symbol;
	}
	public int getAddress() {
	return address;
	}
	public void setAddress(int address) {
	this.address = address;
	}
	}

view raw TableRow.java hosted with ❤ by GitHub

Main Code:-

	import java.io.BufferedReader;
	import java.io.BufferedWriter;
	import java.io.FileReader;
	import java.io.FileWriter;
	import java.util.ArrayList;
	public class Pass2 {
	ArrayList<TableRow> SYMTAB,LITTAB;
	public Pass2()
	{
	SYMTAB=new ArrayList<>();
	LITTAB=new ArrayList<>();
	}
	public static void main(String[] args) {
	Pass2 pass2=new Pass2();
	try {
	pass2.generateCode("IC.txt");
	} catch (Exception e) {
	// TODO Auto-generated catch block
	e.printStackTrace();
	}
	}
	public void readtables()
	{
	BufferedReader br;
	String line;
	try
	{
	br=new BufferedReader(new FileReader("SYMTAB.txt"));
	while((line=br.readLine())!=null)
	{
	String parts[]=line.split("\\s+");
	SYMTAB.add(new TableRow(parts[1], Integer.parseInt(parts[2]),Integer.parseInt(parts[0]) ));
	}
	br.close();
	br=new BufferedReader(new FileReader("LITTAB.txt"));
	while((line=br.readLine())!=null)
	{
	String parts[]=line.split("\\s+");
	LITTAB.add(new TableRow(parts[1], Integer.parseInt(parts[2]),Integer.parseInt(parts[0])));
	}
	br.close();
	}
	catch (Exception e) {
	System.out.println(e.getMessage());
	}
	}
	public void generateCode(String filename) throws Exception
	{
	readtables();
	BufferedReader br=new BufferedReader(new FileReader(filename));
	BufferedWriter bw=new BufferedWriter(new FileWriter("PASS2.txt"));
	String line,code;
	while((line=br.readLine())!=null)
	{
	String parts[]=line.split("\\s+");
	if(parts[0].contains("AD")||parts[0].contains("DL,02"))
	{
	bw.write("\n");
	continue;
	}
	else if(parts.length==2)
	{
	if(parts[0].contains("DL")) //DC INSTR
	{
	parts[0]=parts[0].replaceAll("[^0-9]", "");
	if(Integer.parseInt(parts[0])==1)
	{
	int constant=Integer.parseInt(parts[1].replaceAll("[^0-9]", ""));
	code="00\t0\t"+String.format("%03d", constant)+"\n";
	bw.write(code);
	}
	}
	else if(parts[0].contains("IS"))
	{
	int opcode=Integer.parseInt(parts[0].replaceAll("[^0-9]", ""));
	if(opcode==10)
	{
	if(parts[1].contains("S"))
	{
	int symIndex=Integer.parseInt(parts[1].replaceAll("[^0-9]", ""));
	code=String.format("%02d", opcode)+"\t0\t"+String.format("%03d", SYMTAB.get(symIndex-1).getAddress())+"\n";
	bw.write(code);
	}
	else if(parts[1].contains("L"))
	{
	int symIndex=Integer.parseInt(parts[1].replaceAll("[^0-9]", ""));
	code=String.format("%02d", opcode)+"\t0\t"+String.format("%03d", LITTAB.get(symIndex-1).getAddress())+"\n";
	bw.write(code);
	}
	}
	}
	}
	else if(parts.length==1 && parts[0].contains("IS"))
	{
	int opcode=Integer.parseInt(parts[0].replaceAll("[^0-9]", ""));
	code=String.format("%02d", opcode)+"\t0\t"+String.format("%03d", 0)+"\n";
	bw.write(code);
	}
	else if(parts[0].contains("IS") && parts.length==3) //All OTHER IS INSTR
	{
	int opcode= Integer.parseInt(parts[0].replaceAll("[^0-9]", ""));
	int regcode=Integer.parseInt(parts[1]);
	if(parts[2].contains("S"))
	{
	int symIndex=Integer.parseInt(parts[2].replaceAll("[^0-9]", ""));
	code=String.format("%02d", opcode)+"\t"+regcode+"\t"+String.format("%03d", SYMTAB.get(symIndex-1).getAddress())+"\n";
	bw.write(code);
	}
	else if(parts[2].contains("L"))
	{
	int symIndex=Integer.parseInt(parts[2].replaceAll("[^0-9]", ""));
	code=String.format("%02d", opcode)+"\t"+regcode+"\t"+String.format("%03d", LITTAB.get(symIndex-1).getAddress())+"\n";
	bw.write(code);
	}
	}
	}
	bw.close();
	br.close();
	}
	}

view raw Pass2.java hosted with ❤ by GitHub

Output:-

	04 1 108
	01 1 109
	05 1 101
	10 0 101
	00 0 000
	00 0 019
	00 0 017

view raw Pass2.txt hosted with ❤ by GitHub

You can download source code from this link. ==> SPOS P2_ASM