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Manish Kumar, Lovely Professional University Unit 4: Design of Assembler

Unit 4: Design of Assembler Notes

CONTENTS
Objectives

Introduction
4.1 Design of Assembler
4.1.1 Addressing Options
4.1.2 Statement of Problem
4.1.3 Data Structure
4.1.4 Format of the Databases
4.1.5 Algorithm
4.1.6 Look for Modularity
4.2 Summary

4.3 Keywords
4.4 Review Questions
4.5 Further Readings

Objectives

After studying this unit, you will be able to:
 Understand the concept of designing assembler

 Discuss data structure, format of databases, and algorithm in the design of assembler
 Discuss modularity in the design of assembler
Introduction

An assembler is a program that receives as input an assembly language program and generates its
machine language correspondent along with information for the linker/loader and report for the
consumer. Fundamentally it converts code in one language into another. Assemblers are nothing
more than huge translators that convert code from one language to another following recognized
syntax rules. In many cases the code is converted into machine code with information concerning the
program, position of internal variables that might be referenced by another program, information
concerning local addresses that will require to be updated depending on where the operating system
allocates the program to memory. These activities are the role of the linker/loader.
Figure 4.1

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