Explain about two-pass assembler, Computer Engineering

Assignment Help:

Q. Explain about Two-pass assembler?

Assemblers usually make two or more passes through a source program in order to resolve forward references in a program. A forward reference is expressed as a type of instruction in code segment which is referencing the label of an instruction though the assembler hasn't yet encountered the definition of that instruction.

Pass 1:  Assembler reads the whole source program and creates a symbol table of labels and names used in the program that is name of data fields and programs labels and their relative location (offset) within the segment.

Pass 1 concludes the amount of code to be produced for every instruction. 

Pass 2:Assembler uses the symbol table which it constructed in Pass 1. Now it knows the relative position and length of every data field and instruction and it can complete object code for every instruction.  It generates .OBJ (Object file), .LST (list file) and cross reference (.CRF) files.


Related Discussions:- Explain about two-pass assembler

What is difference between ram and fifo, What is difference between RAM and...

What is difference between RAM and FIFO? FIFO certainly does not have address lines. It is stands for first in and first out. It is an algorithm based method. It is used to s

Parallel edge or self loop of the total number of edges, A graph with n ver...

A graph with n vertices will definitely have a parallel edge or self loop of the total number of edges are More than n(n-1)/2

Explain the disadvantages of random scan display, Disadvantages of random s...

Disadvantages of random scan display - Just by wire-frame, it is almost impossible to create images with shaded objects or areas filled with a given colour. - In case

Value - elements of composition, Value Value is the relative amount of ...

Value Value is the relative amount of light and darkness in an image or a particular colour within an image. Value is also known as Tone and refers to the way the artist has re

Describes the phases of sdlc, Software Development Life Cycle (SDLC):- SDLC...

Software Development Life Cycle (SDLC):- SDLC (System Development Life Cycle) is a well-defined process by which a system is conceived developed and implemented. In other sense a S

Explain about server synchronization, Q. Explain about Server synchronizati...

Q. Explain about Server synchronization? Server synchronization: It updates atom by server process of requesting process. In this method an atom acts as a unique update server.

What are the registers generally contained in the processor, What are the r...

What are the registers generally contained in the processor? MAR-memory address register MDR-memory data register IR-Instruction Register RO-Rn-General purpose registe

Explain design parameters, Explain the following design parameters S, ...

Explain the following design parameters S, SC, TC, C, CCI, EUF, K, T S The various terms are given below: S: Total number of switching components A good design sh

difference among primary and secondary storage device, In primary storage ...

In primary storage device the storage capacity is fixed. It has a volatile memory. In secondary storage device the storage capacity is not limited. It is a nonvolatile memory. Prim

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd