Explain the data dependency, Computer Engineering

Assignment Help:

Data Dependency

It indicates to the situation in which two or more instructions share same data. The instructions in a program are able to be arranged based on relationship of data dependency. It means how two segments or instructions are data dependent on each other. The subsequent types of data dependencies are identified:

i)  Output dependence: When output of the two instructions I1 and I2 overlap on same data, the instructions are said output dependent.  

ii) I/O dependence: When read and write operations by two instructions are invoked on the same file, it's the condition of I/O dependence.

iii) Flow dependence: If instruction I2 follows I1 and output of I1 becomes input of I2, then I2 is said to be flow dependent on I1

iv) Anti dependence: When instruction I2 follows instruction I1 such that output of instruction I2 overlaps with the input of instruction I1 on the same data.

Think about the subsequent program instructions:

I1: a = b

I2: c = a + d

I3: a = c

In this program segment instructions I1 and I2 are Flow dependent since variable a is produced by instruction I1 as output and used by instruction I2 as input. Instructions I2 and I3 are Anti dependent since variable a is produced by I3 but used by I2 and in sequence I2 comes first. I3 is flow dependent on I2 due to variable c. Instructions I3 and Instruction I1 are Output dependent since variable a is produced by both instructions.


Related Discussions:- Explain the data dependency

Explain the main part of step by step switching system, Explain the main pa...

Explain the main part of configuration of a step by step switching system with the help of a neat diagram . Configuration of a step by step switching system: A step

What is an accessor in c++, An accessor is a class operation that does not ...

An accessor is a class operation that does not change the state of an object in C++. The access or functions require to be declared as const operations

What is net-fu and where is it?, Net-fu is a web-based interface to a scri...

Net-fu is a web-based interface to a script-fu server. The work is completed at a remote site. To see Net-fu, point your web browser or one of the mirror sites, and then go to "gim

Explain about control memory organization, Q. Explain about Control Memory ...

Q. Explain about Control Memory Organization? One of the simplest ways to organize control memory is to organize micro-instructions for different sub cycles of machine instruct

Why gateways are used during mail transfer, Why Gateways are used during ma...

Why Gateways are used during mail transfer? Email using SMTP effort best while both the sender and the receiver are on the internet and can hold TCP connections in between send

GRID COMPUTING, I NEED THE CODES IN MATLAB FOR RESOURCE ALLOCATION IN GRID ...

I NEED THE CODES IN MATLAB FOR RESOURCE ALLOCATION IN GRID COMPUTING

What is flash memory, Q. What is Flash Memory? This memory is other fo...

Q. What is Flash Memory? This memory is other form of semiconductor memory that was first introduced in mid-1980.  These memories can be reprogrammed at high speed and therefo

To which one erlang is equal, One Erlang is equal to (A)  3600 CCS ...

One Erlang is equal to (A)  3600 CCS (B)  36 CCS (C) 60 CCS (D)  24 CCS Ans: One Erlang is equivalent to 3600 CCS.

OS, why we say OS is a resource allocator and control program

why we say OS is a resource allocator and control program

What do you mean by execution unit, Q. What do you mean by Execution Unit? ...

Q. What do you mean by Execution Unit? Execution unit performs all ALU operations. Execution unit of 8086 is of 16 bits. It also contains the control unit that instructs bus in

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