11918 verification with system verilog 79 packages

1/19/18 Verification with System Verilog 79

Packages
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Creates a scope that contains declarations intended
to be shared among one or more compilation units,
modules, interfaces, or programs.
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Generally constants, type defs, tasks and functions
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No hierarchical references allowed
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OOP Concepts
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For more Course Resources, Tutorials see
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What is OOP?
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OOP is object oriented programming
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Organize programs in same way as objects are organized in real
world
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Break program into blocks that work together to accomplish a
task, each block has a well defined interface
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Class – A blueprint for a house
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Program element “containing” related group of features and
functionalities
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Encapsulates functionality
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Provides a template for building objects
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Class Basics
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A Class is a description of some group of things that have
something in common.
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Objects are individual instances of “classes”.
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Example: A class might be “Automobile”. Instances of
the “Automobile” class might be “Joe’s car”, “Bob’s
car”, “Sally’s truck”, etc.
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Objects/Classes have:
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Data
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Color, speed, direction, etc.
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Operations/Methods
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Start, stop, increaseSpeed, turn, etc.
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Encapsulation:
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Encapsulate implementation details internal to the
object/class.
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Classes
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Inheritance : (is-a relationship)
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Allows users to extend existing classes, making minor
modifications. Extending the “Automobile” class example,
users might create subclasses for “sedan”, “truck”, “van”,
etc. The “van” class might also have a “minivan” subclass.
Etc. In these cases, the subclass IS-A superclass. i.e. a
“sedan” is a “Automobile”.
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When using inheritance, the sub-class “inherits” all the
parents public/protected data properties and methods. It is
allowed to override them, or use them as-is.
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Composition: (has-a relationship)
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Composition is used for the case where one object HAS-A
instance of another class. For example, an “Automobile”
class might have 4 instances of a “wheel” class. In this case,
a wheel is not an “Automobile”, so inheritance should not
be used.
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Classes
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Polymorphism:
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Most common definition of polymorphism is the ability of the
language to process objects differently depending on their data
type or class . System Verilog can only process objects differently
depending on their class.
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The primary usage of polymorphism in industry (object-oriented
programming theory) is the ability of objects belonging to
different types to respond to method, field, or property calls of
the same name, each one according to an appropriate type-
specific behavior.