byucc.edif
Class EdifPort

java.lang.Object
  byucc.edif.NamedPropertyObject
      byucc.edif.EdifPort

All Implemented Interfaces:

EdifOut, Nameable, Properties, java.io.Serializable

public class EdifPort

extends NamedPropertyObject

implements EdifOut, java.io.Serializable

Represents an Edif port, which belongs to a specific EdifCell. This class specifies a port direction (IN, OUT or INOUT), and a width for support of multi-bit ports.

Note that this object is immutable. Once this object has been created, it cannot be changed.

The purpose of an EdifPort object is to connect a net from the outer level of hierarchy to the inner level of heirarchy.

Sample EDIF code for an EdifPort:

    (cell RAMB4_S2 (cellType GENERIC)
       (view PRIM (viewType NETLIST)
         (interface
           (port (array (rename do "DO[1:0]") 2) (direction OUTPUT))
           (port (array (rename addr "ADDR[10:0]") 11) (direction INPUT))
           (port (array (rename di "DI[1:0]") 2) (direction INPUT))
           (port EN (direction INPUT))
           (port CLK (direction INPUT))
           (port WE (direction INPUT))
           (port RST (direction INPUT))
         )
       )
    )
 

To Do:

• A way of keeping track of which nets are attached to each Port. This involves two different sub-tasks: keeping track of inner nets and keeping track of outer nets. The EdifPort objects associated with EdifCell objects could keep track of the "inner" net. We can keep track of the "outer" nets by providing a reference of the EdifPortRef within the EdifCellInstance.

Version:

$Id: EdifPort.java,v 1.57 2004/08/27 19:16:42 tsa6 Exp $

Author:

Welson Sun, Mike Wirthlin, Tyler Anderson

See Also:

Serialized Form

Field Summary

(package private) EdifNet[]	_cachedInnerNets Inner net: An inner net is the EdifNet array *within* the EdifCell object that are connected to this particular port.
private int	_direction The direction of this EdifPort
private EdifCellInterface	_parentInterface The EdifCellInterface to which the EdifPort belongs
static int	IN Constant value representing that the EdifPort direction is IN.
static int	INOUT Constant value representing that the EdifPort direction is INOUT.
static int	OUT Constant value representing that the EdifPort direction is OUT.
private EdifSingleBitPort[]	singleBitPorts

Fields inherited from class byucc.edif.NamedPropertyObject

Constructor Summary

EdifPort(EdifCellInterface parent, EdifNameable name, int width, int direction)
Constructs an EdifPort according to the passed in name, width and direction.

EdifPort(EdifCellInterface parent, java.lang.String name, int width, int direction)
Constructs an EdifPort according to the passed in name, width and direction.

Method Summary

boolean	busMatch(java.util.Collection ports)
boolean	busMatch(java.util.Collection ports, boolean ignoreBusDirection) This method allows busses to match.
boolean	busMatch(EdifPort port)
boolean	busMatch(EdifPort port, boolean ignoreBusDirection) This method allows busses to match.
static boolean	busMatch(EdifPort bus, java.util.Collection ports) Overloaded method defaulting to ignoring direction of the individual ports.
private static boolean	busMatch(EdifPort bus, java.util.Collection ports, boolean ignoreBusDirection) This method allows busses to match.
boolean	busMatchWithin(java.util.Collection ports)
boolean	busMatchWithin(java.util.Collection ports, boolean ignoreBusDirection) Returns true if this EdifPort Object contains a bus match with one of the EdifPort Objects in the passed-in Collection.
void	createCachedInnerNets() This method will create the array of EdifNet objects.
boolean	equals(EdifPort port) This method determines whether the EdifPort object passed in is the same as this EdifPort object.
private static boolean	equals(EdifPort port1, EdifPort port2) This method determines whether the EdifPort object passed in is the same as the other passed-in EdifPort object.
private static boolean	equals(EdifPort port1, EdifPort port2, boolean ignoreDirection) This method determines whether the EdifPort object passed in is the same as the other passed-in EdifPort object.
java.lang.String	getBaseName()
int	getBitPosition()
EdifCellInterface	getCellInterface() Returns the EdifCell which this EdifPort belongs to
int	getDirection() Returns the EdifPort's direction There are three kinds of directions in this package: IN OUT INOUT
java.lang.String	getDirectionString()
EdifCell	getEdifCell() Returns the EdifCell that contains this port.
EdifNet	getInnerNet() This method will return the EdifNet which connects this one bit wide EdifPort.
EdifNet	getInnerNet(int member) This method will return the EdifNet which connects the designated bus member of this EdifPort.
EdifNet[]	getInnerNets() This method will return an array of EdifNets, each EdifNet connects the corresponding bus member of this EdifPort( array index = bus member) inside the EdifCell which this EdifPort belongs to.
int	getLSB()
int	getMSB()
static EdifPort	getPortAtPosition(int bitPosition, java.util.Collection ports) Returns the EdifPort Object from the passed-in Collection of ports that match the passed-in bitPosition.
EdifSingleBitPort	getSingleBitPort(int i)
int	getWidth() Returns the EdifPort's width
private void	init(EdifCellInterface parent, int width, int direction) Helper function for the constructor.
void	invalidateCachedInnerNets() Invalidates cached inner nets.
boolean	isBus() Returns true if this port is a bus-port, false otherwise.
boolean	isInOut() Check if this port's direction is bidirectional
boolean	isInput() Check if this port's direction is input, meaning IN or INOUT
boolean	isInputOnly() Check if this port's direction is input only, meaning IN but not INOUT
boolean	isOutput() Check if this port's direction is output, meaning OUT or INOUT
boolean	isOutputOnly() Check if this port's direction is output only, meaning OUT but not INOUT
boolean	isPartOfBus()
static void	makeDirectionsMatch(java.util.Collection dontChange, java.util.Collection change) Makes the directions of the second collection match the directions in the second collection.
boolean	matchesWithin(java.util.Collection portRefs) Returns true if this EdifPort Object equals one of the passed-in collection of EdifPortRef Object's EdifPort.
static int	oppositeDirection(int dir) Return the opposite direction
void	toEdif(EdifPrintWriter epw) Writes the EDIF representation of this EdifPort object to the EdifPrintWriter passed as a parameter.
java.lang.String	toString() Returns the string representation of the EdifPort

Methods inherited from class byucc.edif.NamedPropertyObject

addProperty, addProperty, equals, equalsProperties, getEdifNameable, getName, getProperty, getPropertyList, rename, rename

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

IN

public static final int IN

Constant value representing that the EdifPort direction is IN.

See Also:

Constant Field Values

OUT

public static final int OUT

Constant value representing that the EdifPort direction is OUT.

See Also:

Constant Field Values

INOUT

public static final int INOUT

Constant value representing that the EdifPort direction is INOUT.

See Also:

Constant Field Values

_direction

private int _direction

The direction of this EdifPort

singleBitPorts

private EdifSingleBitPort[] singleBitPorts

_parentInterface

private EdifCellInterface _parentInterface

The EdifCellInterface to which the EdifPort belongs

_cachedInnerNets

EdifNet[] _cachedInnerNets

Inner net: An inner net is the EdifNet array *within* the EdifCell object that are connected to this particular port. They are called inner nets because they are "inside" this edif cell (i.e. on the inside side of the port).

An array of EdifNet references, one for each bus member of this EdifPort. Each referenced EdifNet connects to the corresponding EdifPort bus member inside the EdifCell which this EdifPort belongs to.

Note that this information is cached and is a duplication of information already contained in this data structure. The "owner" of this information is the parent EdifCell. The EdifCell contains this information in the list of EdifNets that connect ports within the Cell.

Because this data structure is a duplication, it can potentially be inconsistent with "true" data structure. To account for this, this data structure is "cached" and created only when needed. Whenever the circuit changes, this cached data is invalidated.

TODO: When should this data structure be invalidated?

• Whenever anything in EdifCell changes (agressive)
• Whenever any net changes in EdifCell
• Whenever any net connected to this EdifPort changes
• Whenever this object is modified--No longer possible.

Who can change EdifPort?

// * @see EdifCellInstance#_cachedOuterNets

Constructor Detail

EdifPort

public EdifPort(EdifCellInterface parent,
                java.lang.String name,
                int width,
                int direction)

Constructs an EdifPort according to the passed in name, width and direction.

Parameters:

parent - The parent of this new EdifPort

name - The name of this Object

width - The width of this EdifPort

direction - The direction of this EdifPort

EdifPort

public EdifPort(EdifCellInterface parent,
                EdifNameable name,
                int width,
                int direction)

Constructs an EdifPort according to the passed in name, width and direction.

Parameters:

parent - The parent of this new EdifPort

name - The Object holding name information for this EdifPort Object

width - The width of this EdifPort

direction - The direction of this EdifPort

Method Detail

init

private void init(EdifCellInterface parent,
                  int width,
                  int direction)

Helper function for the constructor.

Parameters:

parent - The parent of this new EdifPort

width - The width of this EdifPort

direction - The direction of this EdifPort

getSingleBitPort

public EdifSingleBitPort getSingleBitPort(int i)

busMatchWithin

public boolean busMatchWithin(java.util.Collection ports,
                              boolean ignoreBusDirection)

Returns true if this EdifPort Object contains a bus match with one of the EdifPort Objects in the passed-in Collection.

Parameters:

ports - The Collection of ports to find a bus match with

Returns:

True if a bus match exists

busMatchWithin

public boolean busMatchWithin(java.util.Collection ports)

busMatch

public boolean busMatch(EdifPort port,
                        boolean ignoreBusDirection)

This method allows busses to match. Returns true if both ports match, and if one's a bus and the other isn't then all the port objects have the same basename as the bus will be fetched from the single ports parent cell for bus comparison.

Parameters:

port - The EdifPort Object to find a bus match with this one

ignoreBusDirection - If true, the direction of the individual ports will be ignored

Returns:

True if the passed-in port bus-matches with this EdifPort Object

See Also:

busMatch(EdifPort,Collection,boolean)

busMatch

public boolean busMatch(EdifPort port)

busMatch

public boolean busMatch(java.util.Collection ports,
                        boolean ignoreBusDirection)

This method allows busses to match. If this port is not a bus then it cannot be compared as a bus to a collection of ports. If it is a bus then it will be compared to the collection of ports for a match.

Parameters:

ports - A Collection of EdifPort Objects to compare for a bus-match with this EdifPort Object

ignoreBusDirection - If true, the direction of the individual ports will be ignored

Returns:

True if this EdifPort Object bus-matches with the passed-in Collection of EdifPort Objects

See Also:

busMatch(EdifPort,Collection,boolean)

busMatch

public boolean busMatch(java.util.Collection ports)

busMatch

private static boolean busMatch(EdifPort bus,
                                java.util.Collection ports,
                                boolean ignoreBusDirection)

This method allows busses to match. Returns true if the bus has the same width as the # of ports in the collection, and that a wire in the collection of port's bit position maps to each bit in the bus. Each port in the collection must also have the same basename and direction as the bus.

Parameters:

bus - The EdifPort Object to find a bus match with the collection of passed-in EdifPort Objects

ports - A Collection of EdifPort Objects to compare for a bus-match with the passed in bus parameter

ignoreBusDirection - If true, the matching algorithm will ignore the direction of the passed-in ports

Returns:

True if the passed-in bus bus-matches with the passed-in Collection of EdifPort Objects

See Also:

busMatch(EdifPort), busMatch(Collection)

busMatch

public static boolean busMatch(EdifPort bus,
                               java.util.Collection ports)

Overloaded method defaulting to ignoring direction of the individual ports.

Parameters:

bus - The EdifPort Object to find a bus match with the collection of passed-in EdifPort Objects

ports - A Collection of EdifPort Objects to compare for a bus-match with the passed in bus parameter

Returns:

True if the passed-in bus bus-matches with the passed-in Collection of EdifPort Objects

See Also:

busMatch(EdifPort,Collection,boolean)

createCachedInnerNets

public void createCachedInnerNets()

This method will create the array of EdifNet objects. Each element of the array corresponds to one bit of the EdifPort. The EdifNet associated with each port corresponds to the Net that is connected from *within* the cell.

equals

public boolean equals(EdifPort port)

This method determines whether the EdifPort object passed in is the same as this EdifPort object.

Parameters:

port - The EdifPort object to compare for equality with this EdifPort Object

Returns:

True if the passed-in EdifPort Object matches with this one

See Also:

equals(EdifPort,EdifPort)

equals

private static boolean equals(EdifPort port1,
                              EdifPort port2,
                              boolean ignoreDirection)

This method determines whether the EdifPort object passed in is the same as the other passed-in EdifPort object.

This method determines whether the two EdifPort objects are the same. The following criteria are used to make this comparison:

• Neither of the two ports are null.
• The parent cells of both ports match each other.
• The base name of both ports are the same.
• The direction of the two ports are the same
• The width of the two ports are the same

Parameters:

port1 - The first port used for comparison

port2 - The second port used for comparison

ignoreDirection - Specifies whether the port directions during a compare will be ignored or not

Returns:

True if the two ports match each other

See Also:

equals(EdifPort)

equals

private static boolean equals(EdifPort port1,
                              EdifPort port2)

This method determines whether the EdifPort object passed in is the same as the other passed-in EdifPort object.

This method determines whether the two EdifPort objects are the same. The following criteria are used to make this comparison:

• Neither of the two ports are null.
• The parent cells of both ports match each other.
• The base name of both ports are the same.
• The direction of the two ports are the same
• The width of the two ports are the same

Parameters:

port1 - The first port used for comparison

port2 - The second port used for comparison

Returns:

True if the two ports match each other

See Also:

equals(EdifPort,EdifPort,boolean), equals(EdifPort)

getCellInterface

public EdifCellInterface getCellInterface()

Returns the EdifCell which this EdifPort belongs to

Returns:

an EdifCell value representing the EdifCellInterface of this EdifPort Object

getEdifCell

public EdifCell getEdifCell()

Returns the EdifCell that contains this port.

Returns:

An EdifCell that contains this EdifPort in its EdifCellInterface

getInnerNets

public EdifNet[] getInnerNets()

This method will return an array of EdifNets, each EdifNet connects the corresponding bus member of this EdifPort( array index = bus member) inside the EdifCell which this EdifPort belongs to. If this port is a single-bit port, this method will return an array of length one.

Returns:

An array of EdifNet objects representing all the EdifNets that connect to this EdifPort Object

getInnerNet

public EdifNet getInnerNet(int member)

This method will return the EdifNet which connects the designated bus member of this EdifPort. This is offset to zero for busses that begin at values higher than zero.

Parameters:

member - an int representing the index of the EdifNet of this bus

Returns:

an EdifNet representing the EdifNet at the specified index

getInnerNet

public EdifNet getInnerNet()

This method will return the EdifNet which connects this one bit wide EdifPort.

Returns:

an EdifNet value representing the EdifNet Object that this EdifPort is connected to on the inside

getLSB

public int getLSB()

See Also:

EdifBusNameOps.getLSB(byucc.edif.EdifNameable)

getMSB

public int getMSB()

See Also:

EdifBusNameOps.getMSB(byucc.edif.EdifNameable)

getDirection

public int getDirection()

Returns the EdifPort's direction There are three kinds of directions in this package: IN OUT INOUT

Returns:

The direction of the port

getDirectionString

public java.lang.String getDirectionString()

getWidth

public int getWidth()

Returns the EdifPort's width

Returns:

an int representing the width of this EdifPort

getBaseName

public java.lang.String getBaseName()

See Also:

EdifBusNameOps.getBaseName(java.lang.String)

getBitPosition

public int getBitPosition()

See Also:

EdifBusNameOps.getBitPosition(java.lang.String)

getPortAtPosition

public static EdifPort getPortAtPosition(int bitPosition,
                                         java.util.Collection ports)

Returns the EdifPort Object from the passed-in Collection of ports that match the passed-in bitPosition. If no match exists then null is returned.

Parameters:

bitPosition - The bit position is used to find the EdifPort Object to return

ports - The Collection of EdifPort Objects to find one that matches the passed-in bit position

Returns:

An EdifPort Object that has a bit-position that matches the passed-in bitPosition parameter, or null if no match exists

invalidateCachedInnerNets

public void invalidateCachedInnerNets()

Invalidates cached inner nets.

isPartOfBus

public boolean isPartOfBus()

See Also:

EdifBusNameOps.isPartOfBus(java.lang.String)

isBus

public boolean isBus()

Returns true if this port is a bus-port, false otherwise. Equality is done by seeing if singleBitPorts.length > 1.

Returns:

True if this EdifPort Object has a width > 1, meaning that its a bus

isInOut

public boolean isInOut()

Check if this port's direction is bidirectional

Returns:

True if this EdifPort Object is InOut

isInput

public boolean isInput()

Check if this port's direction is input, meaning IN or INOUT

Returns:

True if this EdifPort Object is Input or InOut

isInputOnly

public boolean isInputOnly()

Check if this port's direction is input only, meaning IN but not INOUT

Returns:

True if this EdifPort Object is Input only

isOutput

public boolean isOutput()

Check if this port's direction is output, meaning OUT or INOUT

Returns:

True if this EdifPort Object is Output or InOut

isOutputOnly

public boolean isOutputOnly()

Check if this port's direction is output only, meaning OUT but not INOUT

Returns:

True if this EdifPort Object is Output only

matchesWithin

public boolean matchesWithin(java.util.Collection portRefs)

Returns true if this EdifPort Object equals one of the passed-in collection of EdifPortRef Object's EdifPort. Equality done by '=='.

Parameters:

portRefs - A Collection of EdifPortRef Objects that this EdifPort Object will be compared to in order to determine if a match exists between this EdifPort Object, and an EdifPortRef Object within the Collection

Returns:

True if a match exists between this EdifPort Object and an EdifPortRef Object within the passed-in Collection of EdifPortRef Objects

makeDirectionsMatch

public static void makeDirectionsMatch(java.util.Collection dontChange,
                                       java.util.Collection change)

Makes the directions of the second collection match the directions in the second collection.

Parameters:

dontChange - The Collection whose directions will be standard

change - The Collection whose directions will conform to the first

oppositeDirection

public static int oppositeDirection(int dir)

Return the opposite direction

Parameters:

dir - an int value representing the direction of the EdifPort Object

Returns:

an int value representing the opposite direction of the passed-in dir parameter

toEdif

public void toEdif(EdifPrintWriter epw)

Writes the EDIF representation of this EdifPort object to the EdifPrintWriter passed as a parameter.

Specified by:

toEdif in interface EdifOut

Parameters:

epw - an EdifPrintWriter Object where the EDIF data will be written to

toString

public java.lang.String toString()

Returns the string representation of the EdifPort

Returns:

a String value representing this Object, its direction and inner nets