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

Positive logic nand gate is equivalent to negative logic nor, Show that a p...

Show that a positive logic NAND gate is equivalent to negative logic NOR gate. Ans:  Positive logic denotes True or 1 with a high voltage and False or 0 with a low volt

How the simulation is done - Weather simulation, How the simulation is done...

How the simulation is done -  Information from the satellites/sensors sent to computer -  This data is compared to information stored on files ..... -  ..... Which contain kno

Explain about annotational notations, Explain about Annotational Notations ...

Explain about Annotational Notations These notations may be applied to describe remark and illuminate about any element in the model. They are considered as explanatory of U

Network, Give an intuitive explanation of why the maximum throughput, for s...

Give an intuitive explanation of why the maximum throughput, for small beta, is approximately the same for CSMA slotted Aloha and FCFS splitting with CSMA. Show the optimal expecte

Ease of learning - user friendliness, Ease of Learning - User Friendliness ...

Ease of Learning - User Friendliness Much has been made recently of increasing sophistication in technology with one of the major benefits advertised as an increase in somethi

Explain about ALU organisation, ALU ORGANISATION An ALU performs simple...

ALU ORGANISATION An ALU performs simple arithmetic and logic operation as well as shift operations. Complexity of an ALU relies on the type of instruction set for that it has b

What are the types of electronic payment system, What are the types of elec...

What are the types of electronic payment system? Types of the electronic payment system are as given below: The most Internet payment way for Business to Customer is credit

How many two-input AND and OR gates are required to realize , How many two-...

How many two-input AND and OR gates are required to realize Y=CD+EF+G ? Ans. Y=CD+EF+G No. of two i/p AND gates=2 No. of two i/p OR gates = 2 One OR gate to OR CD and EF

Write a short note on mmx technology, Write a short note on MMX technology....

Write a short note on MMX technology. MMX (Multimedia extensions) technology adds 57 new instructions to instruction set of the Pentium - 4 microprocessors. MMX technology also

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