org.opencores.structure
Class NodeLUT

java.lang.Object
  |
  +--org.opencores.structure.Node
        |
        +--org.opencores.structure.NodeLUT

Direct Known Subclasses:

NodePrim

public class NodeLUT

extends Node

LUT cell type class. It implements function, and allows joining last port is always output, first width-1 are always inputs

Field Summary

byte[]	func function data stored here parameters are ordered like in ports, 8 bits per byte
int	OUT which port is output port

Fields inherited from class org.opencores.structure.Node

dir, flag, fx, fy, INOUT, INPUT, link, name, nfx, nfy, OUTPUT, ports, temp, visited, weight, width, x, y

Constructor Summary

NodeLUT(int width)
constructs empty LUT

NodeLUT(NodeLUT a, NodeLUT b, boolean updateNets)
Constructor, that joins two specified adjacent LUTs and creates new one.

Method Summary

int	calc(int inputs) Calculates LUTs function
java.lang.Object	clone() creates new (unlinked) node with same parameters.
void	duplicate(NodeLUT n) duplicates parameters from n to this
static boolean	isAChild(NodeLUT a, NodeLUT b) Determines, if a is a child of b.
static int	NumJoinInputs(NodeLUT a, NodeLUT b) Function, that returns number of inputs if two specified LUTs were joined, not counting matching inputs.
static int	NumJoinInputsEx(NodeLUT a, NodeLUT b) Function, that returns number of inputs if two specified LUTs were joined, not counting matching inputs nor inbetween connections.
void	permutateInputs(int[] pi) Permutates inputs by pi.
void	permutateInputsInv(int[] pi) Permutates inputs by inv(pi).
private int	size() length of function data
java.lang.String	toString()

Methods inherited from class org.opencores.structure.Node

duplicate, linkNets, setWidth, unlinkNets

Methods inherited from class java.lang.Object

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

Field Detail

OUT

public int OUT

which port is output port

func

public byte[] func

function data stored here parameters are ordered like in ports, 8 bits per byte

Constructor Detail

NodeLUT

public NodeLUT(NodeLUT a,
               NodeLUT b,
               boolean updateNets)

Constructor, that joins two specified adjacent LUTs and creates new one. Removes matching inputs and repairs function accordingly. But it does not remove LUTs nor nets from graph.

Parent MUST drive child's input, and parent MUST NOT have any other childs. It is not possible to do this more generally, since we may have loops.

Parameters:

a - parent LUT

b - child LUT

updateNets - whether this function should update net ports

NodeLUT

public NodeLUT(int width)

constructs empty LUT

Parameters:

width - number of ports (including output!)

Method Detail

size

private int size()

length of function data

Returns:

number of possible inputs

NumJoinInputs

public static final int NumJoinInputs(NodeLUT a,
                                      NodeLUT b)

Function, that returns number of inputs if two specified LUTs were joined, not counting matching inputs.

Parent can drive child's input. It is not possible to do this more generally, since we can have loops.

Parameters:

a - parent LUT

b - child LUT

Returns:

number of inputs

isAChild

public static final boolean isAChild(NodeLUT a,
                                     NodeLUT b)

Determines, if a is a child of b.

Parameters:

a - any LUT

b - any LUT

Returns:

true if a is child of b, and false when b is child of a, or a and b are uncorrelated.

NumJoinInputsEx

public static final int NumJoinInputsEx(NodeLUT a,
                                        NodeLUT b)

Function, that returns number of inputs if two specified LUTs were joined, not counting matching inputs nor inbetween connections.

Parameters:

a - LUT

b - LUT

Returns:

number of inputs

permutateInputs

public void permutateInputs(int[] pi)
                     throws java.lang.Exception

Permutates inputs by pi.

Parameters:

pi - permutation (pi[source_index]=destination_index), must be same length as width-1

permutateInputsInv

public void permutateInputsInv(int[] pi)
                        throws java.lang.Exception

Permutates inputs by inv(pi).

Parameters:

pi - inverse permutation (pi[dest_index]=source_index), must be same length as width-1

calc

public final int calc(int inputs)

Calculates LUTs function

Parameters:

inputs - inputs passed to function, LSB is first parameter

Returns:

0 or 1

toString

public java.lang.String toString()

Overrides:

toString in class Node

clone

public java.lang.Object clone()

creates new (unlinked) node with same parameters.

Returns:

duplicated node

Overrides:

clone in class Node

duplicate

public void duplicate(NodeLUT n)

duplicates parameters from n to this

Parameters:

n - node to copy data from