Functions for BDD and ADD reduction by linear transformations. More...

#include "util.h"
#include "cuddInt.h"

Include dependency graph for cuddLinear.c:

Macros
#define	CUDD_SWAP_MOVE 0

#define	CUDD_LINEAR_TRANSFORM_MOVE 1

#define	CUDD_INVERSE_TRANSFORM_MOVE 2

#define	BPL 64

#define	LOGBPL 6

Functions
int	Cudd_PrintLinear (DdManager *table)
	Prints the linear transform matrix. More...

int	Cudd_ReadLinear (DdManager *table, int x, int y)
	Reads an entry of the linear transform matrix. More...

int	cuddLinearAndSifting (DdManager *table, int lower, int upper)
	BDD reduction based on combination of sifting and linear transformations. More...

int	cuddLinearInPlace (DdManager *table, int x, int y)
	Linearly combines two adjacent variables. More...

void	cuddUpdateInteractionMatrix (DdManager *table, int xindex, int yindex)
	Updates the interaction matrix. More...

int	cuddInitLinear (DdManager *table)
	Initializes the linear transform matrix. More...

int	cuddResizeLinear (DdManager *table)
	Resizes the linear transform matrix. More...

static int	ddLinearUniqueCompare (void const ptrX, void const ptrY)
	Comparison function used by qsort. More...

static int	ddLinearAndSiftingAux (DdManager *table, int x, int xLow, int xHigh)
	Given xLow <= x <= xHigh moves x up and down between the boundaries. More...

static Move *	ddLinearAndSiftingUp (DdManager table, int y, int xLow, Move prevMoves)
	Sifts a variable up and applies linear transformations. More...

static Move *	ddLinearAndSiftingDown (DdManager table, int x, int xHigh, Move prevMoves)
	Sifts a variable down and applies linear transformations. More...

static int	ddLinearAndSiftingBackward (DdManager table, int size, Move moves)
	Given a set of moves, returns the DD heap to the order giving the minimum size. More...

static Move *	ddUndoMoves (DdManager table, Move moves)
	Given a set of moves, returns the DD heap to the order in effect before the moves. More...

static void	cuddXorLinear (DdManager *table, int x, int y)
	XORs two rows of the linear transform matrix. More...

Detailed Description

Functions for BDD and ADD reduction by linear transformations.

Author: Fabio Somenzi

Copyright

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

Neither the name of the University of Colorado nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Function Documentation

◆ Cudd_PrintLinear()

int Cudd_PrintLinear ( DdManager * table )

Prints the linear transform matrix.

Returns: 1 in case of success; 0 otherwise.

Side effects none

◆ Cudd_ReadLinear()

int Cudd_ReadLinear	(	DdManager *	table,
		int	x,
		int	y
	)

Reads an entry of the linear transform matrix.

Side effects none

Parameters

table	CUDD manager
x	row index
y	column index

◆ cuddInitLinear()

int cuddInitLinear ( DdManager * table )

Initializes the linear transform matrix.

Returns: 1 if successful; 0 otherwise.

Side effects none

◆ cuddLinearAndSifting()

int cuddLinearAndSifting	(	DdManager *	table,
		int	lower,
		int	upper
	)

BDD reduction based on combination of sifting and linear transformations.

Assumes that no dead nodes are present.

Order all the variables according to the number of entries in each unique table.
Sift the variable up and down, remembering each time the total size of the DD heap. At each position, linear transformation of the two adjacent variables is tried and is accepted if it reduces the size of the DD.
Select the best permutation.
Repeat 3 and 4 for all variables.

Returns: 1 if successful; 0 otherwise.

Side effects None

◆ cuddLinearInPlace()

int cuddLinearInPlace	(	DdManager *	table,
		int	x,
		int	y
	)

Linearly combines two adjacent variables.

Specifically, replaces the top variable with the exclusive nor of the two variables. It assumes that no dead nodes are present on entry to this procedure. The procedure then guarantees that no dead nodes will be present when it terminates. cuddLinearInPlace assumes that x < y.

Returns: the number of keys in the table if successful; 0 otherwise.

Side effects The two subtables corrresponding to variables x and y are: modified. The global counters of the unique table are also affected.

See also: cuddSwapInPlace

◆ cuddResizeLinear()

int cuddResizeLinear ( DdManager * table )

Resizes the linear transform matrix.

Returns: 1 if successful; 0 otherwise.

Side effects none

◆ cuddUpdateInteractionMatrix()

void cuddUpdateInteractionMatrix	(	DdManager *	table,
		int	xindex,
		int	yindex
	)

Updates the interaction matrix.

Side effects none

◆ cuddXorLinear()

static void cuddXorLinear	(	DdManager *	table,
		int	x,
		int	y
	)

static

XORs two rows of the linear transform matrix.

Replaces the first row with the result.

Side effects none

◆ ddLinearAndSiftingAux()

static int ddLinearAndSiftingAux	(	DdManager *	table,
		int	x,
		int	xLow,
		int	xHigh
	)

static

Given xLow <= x <= xHigh moves x up and down between the boundaries.

At each step a linear transformation is tried, and, if it decreases the size of the DD, it is accepted. Finds the best position and does the required changes.

Returns: 1 if successful; 0 otherwise.

Side effects None

◆ ddLinearAndSiftingBackward()

static int ddLinearAndSiftingBackward	(	DdManager *	table,
		int	size,
		Move *	moves
	)

static

Given a set of moves, returns the DD heap to the order giving the minimum size.

In case of ties, returns to the closest position giving the minimum size.

Returns: 1 in case of success; 0 otherwise.

Side effects None

◆ ddLinearAndSiftingDown()

static Move* ddLinearAndSiftingDown	(	DdManager *	table,
		int	x,
		int	xHigh,
		Move *	prevMoves
	)

static

Sifts a variable down and applies linear transformations.

Moves x down until either it reaches the bound (xHigh) or the size of the DD heap increases too much.

Returns: the set of moves in case of success; NULL if memory is full.

Side effects None

◆ ddLinearAndSiftingUp()

static Move* ddLinearAndSiftingUp	(	DdManager *	table,
		int	y,
		int	xLow,
		Move *	prevMoves
	)

static

Sifts a variable up and applies linear transformations.

Moves y up until either it reaches the bound (xLow) or the size of the DD heap increases too much.

Returns: the set of moves in case of success; NULL if memory is full.

Side effects None

◆ ddLinearUniqueCompare()

static int ddLinearUniqueCompare	(	void const *	ptrX,
		void const *	ptrY
	)

static

Comparison function used by qsort.

Comparison function used by qsort to order the variables according to the number of keys in the subtables.

Returns: the difference in number of keys between the two variables being compared.

Side effects None

◆ ddUndoMoves()

static Move* ddUndoMoves	(	DdManager *	table,
		Move *	moves
	)

static

Given a set of moves, returns the DD heap to the order in effect before the moves.

Returns: 1 in case of success; 0 otherwise.

Side effects None

Macros

Functions

Detailed Description

Function Documentation

◆ Cudd_PrintLinear()

◆ Cudd_ReadLinear()

◆ cuddInitLinear()

◆ cuddLinearAndSifting()

◆ cuddLinearInPlace()

◆ cuddResizeLinear()

◆ cuddUpdateInteractionMatrix()

◆ cuddXorLinear()

◆ ddLinearAndSiftingAux()

◆ ddLinearAndSiftingBackward()

◆ ddLinearAndSiftingDown()

◆ ddLinearAndSiftingUp()

◆ ddLinearUniqueCompare()

◆ ddUndoMoves()