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

Create perl scripts, Create Perl scripts as required below: a) Create a ...

Create Perl scripts as required below: a) Create a script named select_by_attribute.pl that accepts the name of a LibML documentand the name of a particular attribute from the c

What are the two primary models of supply chain management, What are the tw...

What are the two primary models of Supply Chain Management? The Two Primary models of Supply Chain Management are:- 1.  Porter's Value Chain Model 2. Supply Chain Model

Convert a JK flipflop to T type flipflop, With the help of a suitable diagr...

With the help of a suitable diagram, explain how do you convert a JK flipflop to T type flipflop. Ans. As here flip flop is JK flip flop and it is required to convert JK in T.

What is program-controlled i/o, What is program-controlled I/O? In prog...

What is program-controlled I/O? In program controlled I/O the processor repeatedly checks a status flags to achieve the needed synchronization among the processor and an input

Representation in prolog - logic programs, Representation in Prolog - Logic...

Representation in Prolog - Logic Programs: If we justimpose some additional constraints on first-order logic, so than we get to a representation language knowing as logic prog

What is the difference between in two lines of verilog code, What is the di...

What is the difference between the following two lines of Verilog code? #5 a = b; a = #5 b; #5 a = b; Wait five time units before doing the action for "a = b;". Value assig

Explain the real time system, What is real time system? A real time sys...

What is real time system? A real time system has well explained, fixed time constraints. Processing must be done within the explained constraints, or the system will fail. It i

What is page stealing, What is Page stealing? Ans. Taking page frames o...

What is Page stealing? Ans. Taking page frames other working sets is called Page stealing.

Connection machine fortran, Q. Connection Machine FORTRAN? Connection M...

Q. Connection Machine FORTRAN? Connection Machine Fortran was a subsequent SIMD language developed by Thinking Machines Corporation. Connection Machine Fortran incorporated all

What is the standard template library (stl), A library of container templat...

A library of container templates approved by the ANSI committee for inclusion in the standard C++ specification. A programmer who then launches into a discussion of the generic

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