/**
  @file 

  @ingroup cudd

  @brief Functions to initialize and shut down the %DD manager.

  @author Fabio Somenzi

  @copyright@parblock
  Copyright (c) 1995-2015, Regents of the University of Colorado

  All rights reserved.

  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.
  @endparblock

*/

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

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/* Type declarations                                                         */
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/* Variable declarations                                                     */
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/* Macro declarations                                                        */
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/** \cond */

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/* Static function prototypes                                                */
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/** \endcond */


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/* Definition of exported functions                                          */
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/**
  @brief Creates a new DD manager.

  @details Initializes the table, the basic constants and the
  projection functions. If maxMemory is 0, Cudd_Init decides suitable
  values for the maximum size of the cache and for the limit for fast
  unique table growth based on the available memory.

  @return a pointer to the manager if successful; NULL otherwise.

  @sideeffect None

  @see Cudd_Quit

*/
DdManager *
Cudd_Init(
  unsigned int numVars /**< initial number of %BDD variables (i.e., subtables) */,
  unsigned int numVarsZ /**< initial number of %ZDD variables (i.e., subtables) */,
  unsigned int numSlots /**< initial size of the unique tables */,
  unsigned int cacheSize /**< initial size of the cache */,
  size_t maxMemory /**< target maximum memory occupation */)
{
    DdManager *unique;
    int i,result;
    DdNode *one, *zero;
    unsigned int maxCacheSize;
    unsigned int looseUpTo;
    extern DD_OOMFP MMoutOfMemory;
    DD_OOMFP saveHandler;

    if (maxMemory == 0) {
	maxMemory = getSoftDataLimit();
    }
    looseUpTo = (unsigned int) ((maxMemory / sizeof(DdNode)) /
				DD_MAX_LOOSE_FRACTION);
    unique = cuddInitTable(numVars,numVarsZ,numSlots,looseUpTo);
    if (unique == NULL) return(NULL);
    unique->maxmem = (size_t) maxMemory / 10 * 9;
    maxCacheSize = (unsigned int) ((maxMemory / sizeof(DdCache)) /
				   DD_MAX_CACHE_FRACTION);
    result = cuddInitCache(unique,cacheSize,maxCacheSize);
    if (result == 0) return(NULL);

    saveHandler = MMoutOfMemory;
    MMoutOfMemory = unique->outOfMemCallback;
    unique->stash = ALLOC(char,(maxMemory / DD_STASH_FRACTION) + 4);
    MMoutOfMemory = saveHandler;
    if (unique->stash == NULL) {
	(void) fprintf(unique->err,"Unable to set aside memory\n");
    }

    /* Initialize constants. */
    unique->one = cuddUniqueConst(unique,1.0);
    if (unique->one == NULL) return(0);
    cuddRef(unique->one);
    unique->zero = cuddUniqueConst(unique,0.0);
    if (unique->zero == NULL) return(0);
    cuddRef(unique->zero);
#ifdef HAVE_IEEE_754
    if (DD_PLUS_INF_VAL != DD_PLUS_INF_VAL * 3 ||
	DD_PLUS_INF_VAL != DD_PLUS_INF_VAL / 3) {
	(void) fprintf(unique->err,"Warning: Crippled infinite values\n");
	(void) fprintf(unique->err,"Recompile without -DHAVE_IEEE_754\n");
    }
#endif
    unique->plusinfinity = cuddUniqueConst(unique,DD_PLUS_INF_VAL);
    if (unique->plusinfinity == NULL) return(0);
    cuddRef(unique->plusinfinity);
    unique->minusinfinity = cuddUniqueConst(unique,DD_MINUS_INF_VAL);
    if (unique->minusinfinity == NULL) return(0);
    cuddRef(unique->minusinfinity);
    unique->background = unique->zero;

    /* The logical zero is different from the CUDD_VALUE_TYPE zero! */
    one = unique->one;
    zero = Cudd_Not(one);
    /* Create the projection functions. */
    unique->vars = ALLOC(DdNodePtr,unique->maxSize);
    if (unique->vars == NULL) {
	unique->errorCode = CUDD_MEMORY_OUT;
	return(NULL);
    }
    for (i = 0; i < unique->size; i++) {
	unique->vars[i] = cuddUniqueInter(unique,i,one,zero);
	if (unique->vars[i] == NULL) return(0);
	cuddRef(unique->vars[i]);
    }

    if (unique->sizeZ)
	cuddZddInitUniv(unique);

    unique->memused += sizeof(DdNode *) * unique->maxSize;

    return(unique);

} /* end of Cudd_Init */


/**
  @brief Deletes resources associated with a %DD manager.

  @details Calling Cudd_Quit with a null pointer has no effect.

  @sideeffect None

  @see Cudd_Init

*/
void
Cudd_Quit(
  DdManager * unique /**< pointer to manager */)
{
    if (unique)
        cuddFreeTable(unique);

} /* end of Cudd_Quit */


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/* Definition of internal functions                                          */
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/**
  @brief Initializes the %ZDD universe.

  @return 1 if successful; 0 otherwise.

  @sideeffect None

  @see cuddZddFreeUniv

*/
int
cuddZddInitUniv(
  DdManager * zdd)
{
    DdNode	*p, *res;
    int		i;

    zdd->univ = ALLOC(DdNodePtr, zdd->sizeZ);
    if (zdd->univ == NULL) {
	zdd->errorCode = CUDD_MEMORY_OUT;
	return(0);
    }

    res = DD_ONE(zdd);
    cuddRef(res);
    for (i = zdd->sizeZ - 1; i >= 0; i--) {
	unsigned int index = zdd->invpermZ[i];
	p = res;
	res = cuddUniqueInterZdd(zdd, index, p, p);
	if (res == NULL) {
	    Cudd_RecursiveDerefZdd(zdd,p);
	    FREE(zdd->univ);
	    return(0);
	}
	cuddRef(res);
	cuddDeref(p);
	zdd->univ[i] = res;
    }

#ifdef DD_VERBOSE
    cuddZddP(zdd, zdd->univ[0]);
#endif

    return(1);

} /* end of cuddZddInitUniv */


/**
  @brief Frees the %ZDD universe.

  @sideeffect None

  @see cuddZddInitUniv

*/
void
cuddZddFreeUniv(
  DdManager * zdd)
{
    if (zdd->univ) {
	Cudd_RecursiveDerefZdd(zdd, zdd->univ[0]);
	FREE(zdd->univ);
    }

} /* end of cuddZddFreeUniv */


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/* Definition of static functions                                            */
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