src/cuBdd/cuddTable.c File Reference

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

Include dependency graph for cuddTable.c:

Go to the source code of this file.

Data Structures
union	hack
Functions
static void	ddRehashZdd (DdManager *unique, int i)
static int	ddResizeTable (DdManager *unique, int index)
static int	cuddFindParent (DdManager *table, DdNode *node)
static DD_INLINE void	ddFixLimits (DdManager *unique)
static void	ddPatchTree (DdManager *dd, MtrNode *treenode)
static int	cuddCheckCollisionOrdering (DdManager *unique, int i, int j)
static void	ddReportRefMess (DdManager *unique, int i, const char *caller)
unsigned int	Cudd_Prime (unsigned int p)
DdNode *	cuddAllocNode (DdManager *unique)
DdManager *	cuddInitTable (unsigned int numVars, unsigned int numVarsZ, unsigned int numSlots, unsigned int looseUpTo)
void	cuddFreeTable (DdManager *unique)
int	cuddGarbageCollect (DdManager *unique, int clearCache)
DdNode *	cuddZddGetNode (DdManager *zdd, int id, DdNode *T, DdNode *E)
DdNode *	cuddZddGetNodeIVO (DdManager *dd, int index, DdNode *g, DdNode *h)
DdNode *	cuddUniqueInter (DdManager *unique, int index, DdNode *T, DdNode *E)
DdNode *	cuddUniqueInterIVO (DdManager *unique, int index, DdNode *T, DdNode *E)
DdNode *	cuddUniqueInterZdd (DdManager *unique, int index, DdNode *T, DdNode *E)
DdNode *	cuddUniqueConst (DdManager *unique, CUDD_VALUE_TYPE value)
void	cuddRehash (DdManager *unique, int i)
void	cuddShrinkSubtable (DdManager *unique, int i)
int	cuddInsertSubtables (DdManager *unique, int n, int level)
int	cuddDestroySubtables (DdManager *unique, int n)
int	cuddResizeTableZdd (DdManager *unique, int index)
void	cuddSlowTableGrowth (DdManager *unique)
Variables
static char rcsid[]	DD_UNUSED = "$Id: cuddTable.c,v 1.122 2009/02/19 16:24:28 fabio Exp $"

---

Function Documentation

unsigned int Cudd_Prime

(

unsigned int

p

)

AutomaticEnd Function********************************************************************

Synopsis [Returns the next prime >= p.]

Description []

SideEffects [None]

Definition at line 184 of file cuddTable.c.

{
    int i,pn;

    p--;
    do {
        p++;
        if (p&1) {
            pn = 1;
            i = 3;
            while ((unsigned) (i * i) <= p) {
                if (p % i == 0) {
                    pn = 0;
                    break;
                }
                i += 2;
            }
        } else {
            pn = 0;
        }
    } while (!pn);
    return(p);

} /* end of Cudd_Prime */

DdNode* cuddAllocNode

(

DdManager *

unique

)

Function********************************************************************

Synopsis [Fast storage allocation for DdNodes in the table.]

Description [Fast storage allocation for DdNodes in the table. The first 4 bytes of a chunk contain a pointer to the next block; the rest contains DD_MEM_CHUNK spaces for DdNodes. Returns a pointer to a new node if successful; NULL is memory is full.]

SideEffects [None]

SeeAlso [cuddDynamicAllocNode]

Definition at line 231 of file cuddTable.c.

{
    int i;
    DdNodePtr *mem;
    DdNode *list, *node;
    extern DD_OOMFP MMoutOfMemory;
    DD_OOMFP saveHandler;

    if (unique->nextFree == NULL) {     /* free list is empty */
        /* Check for exceeded limits. */
        if ((unique->keys - unique->dead) + (unique->keysZ - unique->deadZ) >
            unique->maxLive) {
            unique->errorCode = CUDD_TOO_MANY_NODES;
            return(NULL);
        }
        if (unique->stash == NULL || unique->memused > unique->maxmemhard) {
            (void) cuddGarbageCollect(unique,1);
            mem = NULL;
        }
        if (unique->nextFree == NULL) {
            if (unique->memused > unique->maxmemhard) {
                unique->errorCode = CUDD_MAX_MEM_EXCEEDED;
                return(NULL);
            }
            /* Try to allocate a new block. */
            saveHandler = MMoutOfMemory;
            MMoutOfMemory = Cudd_OutOfMem;
            mem = (DdNodePtr *) ALLOC(DdNode,DD_MEM_CHUNK + 1);
            MMoutOfMemory = saveHandler;
            if (mem == NULL) {
                /* No more memory: Try collecting garbage. If this succeeds,
                ** we end up with mem still NULL, but unique->nextFree !=
                ** NULL. */
                if (cuddGarbageCollect(unique,1) == 0) {
                    /* Last resort: Free the memory stashed away, if there
                    ** any. If this succeeeds, mem != NULL and
                    ** unique->nextFree still NULL. */
                    if (unique->stash != NULL) {
                        FREE(unique->stash);
                        unique->stash = NULL;
                        /* Inhibit resizing of tables. */
                        cuddSlowTableGrowth(unique);
                        /* Now try again. */
                        mem = (DdNodePtr *) ALLOC(DdNode,DD_MEM_CHUNK + 1);
                    }
                    if (mem == NULL) {
                        /* Out of luck. Call the default handler to do
                        ** whatever it specifies for a failed malloc.
                        ** If this handler returns, then set error code,
                        ** print warning, and return. */
                        (*MMoutOfMemory)(sizeof(DdNode)*(DD_MEM_CHUNK + 1));
                        unique->errorCode = CUDD_MEMORY_OUT;
#ifdef DD_VERBOSE
                        (void) fprintf(unique->err,
                                       "cuddAllocNode: out of memory");
                        (void) fprintf(unique->err, "Memory in use = %lu\n",
                                       unique->memused);
#endif
                        return(NULL);
                    }
                }
            }
            if (mem != NULL) {  /* successful allocation; slice memory */
                ptruint offset;
                unique->memused += (DD_MEM_CHUNK + 1) * sizeof(DdNode);
                mem[0] = (DdNodePtr) unique->memoryList;
                unique->memoryList = mem;

                /* Here we rely on the fact that a DdNode is as large
                ** as 4 pointers.  */
                offset = (ptruint) mem & (sizeof(DdNode) - 1);
                mem += (sizeof(DdNode) - offset) / sizeof(DdNodePtr);
                assert(((ptruint) mem & (sizeof(DdNode) - 1)) == 0);
                list = (DdNode *) mem;

                i = 1;
                do {
                    list[i - 1].ref = 0;
                    list[i - 1].next = &list[i];
                } while (++i < DD_MEM_CHUNK);

                list[DD_MEM_CHUNK-1].ref = 0;
                list[DD_MEM_CHUNK-1].next = NULL;

                unique->nextFree = &list[0];
            }
        }
    }
    unique->allocated++;
    node = unique->nextFree;
    unique->nextFree = node->next;
    return(node);

} /* end of cuddAllocNode */

static int cuddCheckCollisionOrdering	(	DdManager *	unique,
		int	i,
		int	j
	)			[static]

Function********************************************************************

Synopsis [Checks whether a collision list is ordered.]

Description []

SideEffects [None]

SeeAlso []

Definition at line 3097 of file cuddTable.c.

{
    int slots;
    DdNode *node, *next;
    DdNodePtr *nodelist;
    DdNode *sentinel = &(unique->sentinel);

    nodelist = unique->subtables[i].nodelist;
    slots = unique->subtables[i].slots;
    node = nodelist[j];
    if (node == sentinel) return(1);
    next = node->next;
    while (next != sentinel) {
        if (cuddT(node) < cuddT(next) ||
            (cuddT(node) == cuddT(next) && cuddE(node) < cuddE(next))) {
            (void) fprintf(unique->err,
                           "Unordered list: index %u, position %d\n", i, j);
            return(0);
        }
        node = next;
        next = node->next;
    }
    return(1);

} /* end of cuddCheckCollisionOrdering */

int cuddDestroySubtables	(	DdManager *	unique,
		int	n
	)

Function********************************************************************

Synopsis [Destroys the n most recently created subtables in a unique table.]

Description [Destroys the n most recently created subtables in a unique table. n should be positive. The subtables should not contain any live nodes, except the (isolated) projection function. The projection functions are freed. Returns 1 if successful; 0 otherwise.]

SideEffects [The variable map used for fast variable substitution is destroyed if it exists. In this case the cache is also cleared.]

SeeAlso [cuddInsertSubtables Cudd_SetVarMap]

Definition at line 2093 of file cuddTable.c.

{
    DdSubtable *subtables;
    DdNodePtr *nodelist;
    DdNodePtr *vars;
    int firstIndex, lastIndex;
    int index, level, newlevel;
    int lowestLevel;
    int shift;
    int found;

    /* Sanity check and set up. */
    if (n <= 0) return(0);
    if (n > unique->size) n = unique->size;

    subtables = unique->subtables;
    vars = unique->vars;
    firstIndex = unique->size - n;
    lastIndex  = unique->size;

    /* Check for nodes labeled by the variables being destroyed
    ** that may still be in use.  It is allowed to destroy a variable
    ** only if there are no such nodes. Also, find the lowest level
    ** among the variables being destroyed. This will make further
    ** processing more efficient.
    */
    lowestLevel = unique->size;
    for (index = firstIndex; index < lastIndex; index++) {
        level = unique->perm[index];
        if (level < lowestLevel) lowestLevel = level;
        nodelist = subtables[level].nodelist;
        if (subtables[level].keys - subtables[level].dead != 1) return(0);
        /* The projection function should be isolated. If the ref count
        ** is 1, everything is OK. If the ref count is saturated, then
        ** we need to make sure that there are no nodes pointing to it.
        ** As for the external references, we assume the application is
        ** responsible for them.
        */
        if (vars[index]->ref != 1) {
            if (vars[index]->ref != DD_MAXREF) return(0);
            found = cuddFindParent(unique,vars[index]);
            if (found) {
                return(0);
            } else {
                vars[index]->ref = 1;
            }
        }
        Cudd_RecursiveDeref(unique,vars[index]);
    }

    /* Collect garbage, because we cannot afford having dead nodes pointing
    ** to the dead nodes in the subtables being destroyed.
    */
    (void) cuddGarbageCollect(unique,1);

    /* Here we know we can destroy our subtables. */
    for (index = firstIndex; index < lastIndex; index++) {
        level = unique->perm[index];
        nodelist = subtables[level].nodelist;
#ifdef DD_DEBUG
        assert(subtables[level].keys == 0);
#endif
        FREE(nodelist);
        unique->memused -= sizeof(DdNodePtr) * subtables[level].slots;
        unique->slots -= subtables[level].slots;
        unique->dead -= subtables[level].dead;
    }

    /* Here all subtables to be destroyed have their keys field == 0 and
    ** their hash tables have been freed.
    ** We now scan the subtables from level lowestLevel + 1 to level size - 1,
    ** shifting the subtables as required. We keep a running count of
    ** how many subtables have been moved, so that we know by how many
    ** positions each subtable should be shifted.
    */
    shift = 1;
    for (level = lowestLevel + 1; level < unique->size; level++) {
        if (subtables[level].keys == 0) {
            shift++;
            continue;
        }
        newlevel = level - shift;
        subtables[newlevel].slots = subtables[level].slots;
        subtables[newlevel].shift = subtables[level].shift;
        subtables[newlevel].keys = subtables[level].keys;
        subtables[newlevel].maxKeys = subtables[level].maxKeys;
        subtables[newlevel].dead = subtables[level].dead;
        subtables[newlevel].nodelist = subtables[level].nodelist;
        index = unique->invperm[level];
        unique->perm[index] = newlevel;
        unique->invperm[newlevel]  = index;
        subtables[newlevel].bindVar = subtables[level].bindVar;
        subtables[newlevel].varType = subtables[level].varType;
        subtables[newlevel].pairIndex = subtables[level].pairIndex;
        subtables[newlevel].varHandled = subtables[level].varHandled;
        subtables[newlevel].varToBeGrouped = subtables[level].varToBeGrouped;
    }
    /* Destroy the map. If a surviving variable is
    ** mapped to a dying variable, and the map were used again,
    ** an out-of-bounds access to unique->vars would result. */
    if (unique->map != NULL) {
        cuddCacheFlush(unique);
        FREE(unique->map);
        unique->map = NULL;
    }

    unique->minDead = (unsigned) (unique->gcFrac * (double) unique->slots);
    unique->size -= n;

    return(1);

} /* end of cuddDestroySubtables */

static int cuddFindParent	(	DdManager *	table,
		DdNode *	node
	)			[static]

Function********************************************************************

Synopsis [Searches the subtables above node for a parent.]

Description [Searches the subtables above node for a parent. Returns 1 as soon as one parent is found. Returns 0 is the search is fruitless.]

SideEffects [None]

SeeAlso []

Definition at line 2743 of file cuddTable.c.

{
    int         i,j;
    int         slots;
    DdNodePtr   *nodelist;
    DdNode      *f;

    for (i = cuddI(table,node->index) - 1; i >= 0; i--) {
        nodelist = table->subtables[i].nodelist;
        slots = table->subtables[i].slots;

        for (j = 0; j < slots; j++) {
            f = nodelist[j];
            while (cuddT(f) > node) {
                f = f->next;
            }
            while (cuddT(f) == node && Cudd_Regular(cuddE(f)) > node) {
                f = f->next;
            }
            if (cuddT(f) == node && Cudd_Regular(cuddE(f)) == node) {
                return(1);
            }
        }
    }

    return(0);

} /* end of cuddFindParent */

void cuddFreeTable

(

DdManager *

unique

)

Function********************************************************************

Synopsis [Frees the resources associated to a unique table.]

Description []

SideEffects [None]

SeeAlso [cuddInitTable]

Definition at line 649 of file cuddTable.c.

{
    DdNodePtr *next;
    DdNodePtr *memlist = unique->memoryList;
    int i;

    if (unique->univ != NULL) cuddZddFreeUniv(unique);
    while (memlist != NULL) {
        next = (DdNodePtr *) memlist[0];        /* link to next block */
        FREE(memlist);
        memlist = next;
    }
    unique->nextFree = NULL;
    unique->memoryList = NULL;

    for (i = 0; i < unique->size; i++) {
        FREE(unique->subtables[i].nodelist);
    }
    for (i = 0; i < unique->sizeZ; i++) {
        FREE(unique->subtableZ[i].nodelist);
    }
    FREE(unique->constants.nodelist);
    FREE(unique->subtables);
    FREE(unique->subtableZ);
    FREE(unique->acache);
    FREE(unique->perm);
    FREE(unique->permZ);
    FREE(unique->invperm);
    FREE(unique->invpermZ);
    FREE(unique->vars);
    if (unique->map != NULL) FREE(unique->map);
    FREE(unique->stack);
#ifndef DD_NO_DEATH_ROW
    FREE(unique->deathRow);
#endif
    if (unique->tree != NULL) Mtr_FreeTree(unique->tree);
    if (unique->treeZ != NULL) Mtr_FreeTree(unique->treeZ);
    if (unique->linear != NULL) FREE(unique->linear);
    while (unique->preGCHook != NULL)
        Cudd_RemoveHook(unique,unique->preGCHook->f,CUDD_PRE_GC_HOOK);
    while (unique->postGCHook != NULL)
        Cudd_RemoveHook(unique,unique->postGCHook->f,CUDD_POST_GC_HOOK);
    while (unique->preReorderingHook != NULL)
        Cudd_RemoveHook(unique,unique->preReorderingHook->f,
                        CUDD_PRE_REORDERING_HOOK);
    while (unique->postReorderingHook != NULL)
        Cudd_RemoveHook(unique,unique->postReorderingHook->f,
                        CUDD_POST_REORDERING_HOOK);
    FREE(unique);

} /* end of cuddFreeTable */

int cuddGarbageCollect	(	DdManager *	unique,
		int	clearCache
	)

Function********************************************************************

Synopsis [Performs garbage collection on the unique tables.]

Description [Performs garbage collection on the BDD and ZDD unique tables. If clearCache is 0, the cache is not cleared. This should only be specified if the cache has been cleared right before calling cuddGarbageCollect. (As in the case of dynamic reordering.) Returns the total number of deleted nodes.]

SideEffects [None]

SeeAlso []

Definition at line 719 of file cuddTable.c.

{
    DdHook      *hook;
    DdCache     *cache = unique->cache;
    DdNode      *sentinel = &(unique->sentinel);
    DdNodePtr   *nodelist;
    int         i, j, deleted, totalDeleted, totalDeletedZ;
    DdCache     *c;
    DdNode      *node,*next;
    DdNodePtr   *lastP;
    int         slots;
    long        localTime;
#ifndef DD_UNSORTED_FREE_LIST
#ifdef DD_RED_BLACK_FREE_LIST
    DdNodePtr   tree;
#else
    DdNodePtr *memListTrav, *nxtNode;
    DdNode *downTrav, *sentry;
    int k;
#endif
#endif

#ifndef DD_NO_DEATH_ROW
    cuddClearDeathRow(unique);
#endif

    hook = unique->preGCHook;
    while (hook != NULL) {
        int res = (hook->f)(unique,"DD",NULL);
        if (res == 0) return(0);
        hook = hook->next;
    }

    if (unique->dead + unique->deadZ == 0) {
        hook = unique->postGCHook;
        while (hook != NULL) {
            int res = (hook->f)(unique,"DD",NULL);
            if (res == 0) return(0);
            hook = hook->next;
        }
        return(0);
    }

    /* If many nodes are being reclaimed, we want to resize the tables
    ** more aggressively, to reduce the frequency of garbage collection.
    */
    if (clearCache && unique->gcFrac == DD_GC_FRAC_LO &&
        unique->slots <= unique->looseUpTo && unique->stash != NULL) {
        unique->minDead = (unsigned) (DD_GC_FRAC_HI * (double) unique->slots);
#ifdef DD_VERBOSE
        (void) fprintf(unique->err,"GC fraction = %.2f\t", DD_GC_FRAC_HI);
        (void) fprintf(unique->err,"minDead = %d\n", unique->minDead);
#endif
        unique->gcFrac = DD_GC_FRAC_HI;
        return(0);
    }

    localTime = util_cpu_time();

    unique->garbageCollections++;
#ifdef DD_VERBOSE
    (void) fprintf(unique->err,
                   "garbage collecting (%d dead BDD nodes out of %d, min %d)...",
                   unique->dead, unique->keys, unique->minDead);
    (void) fprintf(unique->err,
                   "                   (%d dead ZDD nodes out of %d)...",
                   unique->deadZ, unique->keysZ);
#endif

    /* Remove references to garbage collected nodes from the cache. */
    if (clearCache) {
        slots = unique->cacheSlots;
        for (i = 0; i < slots; i++) {
            c = &cache[i];
            if (c->data != NULL) {
                if (cuddClean(c->f)->ref == 0 ||
                cuddClean(c->g)->ref == 0 ||
                (((ptruint)c->f & 0x2) && Cudd_Regular(c->h)->ref == 0) ||
                (c->data != DD_NON_CONSTANT &&
                Cudd_Regular(c->data)->ref == 0)) {
                    c->data = NULL;
                    unique->cachedeletions++;
                }
            }
        }
        cuddLocalCacheClearDead(unique);
    }

    /* Now return dead nodes to free list. Count them for sanity check. */
    totalDeleted = 0;
#ifndef DD_UNSORTED_FREE_LIST
#ifdef DD_RED_BLACK_FREE_LIST
    tree = NULL;
#endif
#endif

    for (i = 0; i < unique->size; i++) {
        if (unique->subtables[i].dead == 0) continue;
        nodelist = unique->subtables[i].nodelist;

        deleted = 0;
        slots = unique->subtables[i].slots;
        for (j = 0; j < slots; j++) {
            lastP = &(nodelist[j]);
            node = *lastP;
            while (node != sentinel) {
                next = node->next;
                if (node->ref == 0) {
                    deleted++;
#ifndef DD_UNSORTED_FREE_LIST
#ifdef DD_RED_BLACK_FREE_LIST
#ifdef __osf__
#pragma pointer_size save
#pragma pointer_size short
#endif
                    cuddOrderedInsert(&tree,node);
#ifdef __osf__
#pragma pointer_size restore
#endif
#endif
#else
                    cuddDeallocNode(unique,node);
#endif
                } else {
                    *lastP = node;
                    lastP = &(node->next);
                }
                node = next;
            }
            *lastP = sentinel;
        }
        if ((unsigned) deleted != unique->subtables[i].dead) {
            ddReportRefMess(unique, i, "cuddGarbageCollect");
        }
        totalDeleted += deleted;
        unique->subtables[i].keys -= deleted;
        unique->subtables[i].dead = 0;
    }
    if (unique->constants.dead != 0) {
        nodelist = unique->constants.nodelist;
        deleted = 0;
        slots = unique->constants.slots;
        for (j = 0; j < slots; j++) {
            lastP = &(nodelist[j]);
            node = *lastP;
            while (node != NULL) {
                next = node->next;
                if (node->ref == 0) {
                    deleted++;
#ifndef DD_UNSORTED_FREE_LIST
#ifdef DD_RED_BLACK_FREE_LIST
#ifdef __osf__
#pragma pointer_size save
#pragma pointer_size short
#endif
                    cuddOrderedInsert(&tree,node);
#ifdef __osf__
#pragma pointer_size restore
#endif
#endif
#else
                    cuddDeallocNode(unique,node);
#endif
                } else {
                    *lastP = node;
                    lastP = &(node->next);
                }
                node = next;
            }
            *lastP = NULL;
        }
        if ((unsigned) deleted != unique->constants.dead) {
            ddReportRefMess(unique, CUDD_CONST_INDEX, "cuddGarbageCollect");
        }
        totalDeleted += deleted;
        unique->constants.keys -= deleted;
        unique->constants.dead = 0;
    }
    if ((unsigned) totalDeleted != unique->dead) {
        ddReportRefMess(unique, -1, "cuddGarbageCollect");
    }
    unique->keys -= totalDeleted;
    unique->dead = 0;
#ifdef DD_STATS
    unique->nodesFreed += (double) totalDeleted;
#endif

    totalDeletedZ = 0;

    for (i = 0; i < unique->sizeZ; i++) {
        if (unique->subtableZ[i].dead == 0) continue;
        nodelist = unique->subtableZ[i].nodelist;

        deleted = 0;
        slots = unique->subtableZ[i].slots;
        for (j = 0; j < slots; j++) {
            lastP = &(nodelist[j]);
            node = *lastP;
            while (node != NULL) {
                next = node->next;
                if (node->ref == 0) {
                    deleted++;
#ifndef DD_UNSORTED_FREE_LIST
#ifdef DD_RED_BLACK_FREE_LIST
#ifdef __osf__
#pragma pointer_size save
#pragma pointer_size short
#endif
                    cuddOrderedInsert(&tree,node);
#ifdef __osf__
#pragma pointer_size restore
#endif
#endif
#else
                    cuddDeallocNode(unique,node);
#endif
                } else {
                    *lastP = node;
                    lastP = &(node->next);
                }
                node = next;
            }
            *lastP = NULL;
        }
        if ((unsigned) deleted != unique->subtableZ[i].dead) {
            ddReportRefMess(unique, i, "cuddGarbageCollect");
        }
        totalDeletedZ += deleted;
        unique->subtableZ[i].keys -= deleted;
        unique->subtableZ[i].dead = 0;
    }

    /* No need to examine the constant table for ZDDs.
    ** If we did we should be careful not to count whatever dead
    ** nodes we found there among the dead ZDD nodes. */
    if ((unsigned) totalDeletedZ != unique->deadZ) {
        ddReportRefMess(unique, -1, "cuddGarbageCollect");
    }
    unique->keysZ -= totalDeletedZ;
    unique->deadZ = 0;
#ifdef DD_STATS
    unique->nodesFreed += (double) totalDeletedZ;
#endif


#ifndef DD_UNSORTED_FREE_LIST
#ifdef DD_RED_BLACK_FREE_LIST
    unique->nextFree = cuddOrderedThread(tree,unique->nextFree);
#else
    memListTrav = unique->memoryList;
    sentry = NULL;
    while (memListTrav != NULL) {
        ptruint offset;
        nxtNode = (DdNodePtr *)memListTrav[0];
        offset = (ptruint) memListTrav & (sizeof(DdNode) - 1);
        memListTrav += (sizeof(DdNode) - offset) / sizeof(DdNodePtr);
        downTrav = (DdNode *)memListTrav;
        k = 0;
        do {
            if (downTrav[k].ref == 0) {
                if (sentry == NULL) {
                    unique->nextFree = sentry = &downTrav[k];
                } else {
                    /* First hook sentry->next to the dead node and then
                    ** reassign sentry to the dead node. */
                    sentry = (sentry->next = &downTrav[k]);
                }
            }
        } while (++k < DD_MEM_CHUNK);
        memListTrav = nxtNode;
    }
    sentry->next = NULL;
#endif
#endif

    unique->GCTime += util_cpu_time() - localTime;

    hook = unique->postGCHook;
    while (hook != NULL) {
        int res = (hook->f)(unique,"DD",NULL);
        if (res == 0) return(0);
        hook = hook->next;
    }

#ifdef DD_VERBOSE
    (void) fprintf(unique->err," done\n");
#endif

    return(totalDeleted+totalDeletedZ);

} /* end of cuddGarbageCollect */

DdManager* cuddInitTable	(	unsigned int	numVars,
		unsigned int	numVarsZ,
		unsigned int	numSlots,
		unsigned int	looseUpTo
	)

Function********************************************************************

Synopsis [Creates and initializes the unique table.]

Description [Creates and initializes the unique table. Returns a pointer to the table if successful; NULL otherwise.]

SideEffects [None]

SeeAlso [Cudd_Init cuddFreeTable]

Definition at line 341 of file cuddTable.c.

{
    DdManager   *unique = ALLOC(DdManager,1);
    int         i, j;
    DdNodePtr   *nodelist;
    DdNode      *sentinel;
    unsigned int slots;
    int shift;

    if (unique == NULL) {
        return(NULL);
    }
    sentinel = &(unique->sentinel);
    sentinel->ref = 0;
    sentinel->index = 0;
    cuddT(sentinel) = NULL;
    cuddE(sentinel) = NULL;
    sentinel->next = NULL;
    unique->epsilon = DD_EPSILON;
    unique->maxGrowth = DD_MAX_REORDER_GROWTH;
    unique->maxGrowthAlt = 2.0 * DD_MAX_REORDER_GROWTH;
    unique->reordCycle = 0;     /* do not use alternate threshold */
    unique->size = numVars;
    unique->sizeZ = numVarsZ;
    unique->maxSize = ddMax(DD_DEFAULT_RESIZE, numVars);
    unique->maxSizeZ = ddMax(DD_DEFAULT_RESIZE, numVarsZ);

    /* Adjust the requested number of slots to a power of 2. */
    slots = 8;
    while (slots < numSlots) {
        slots <<= 1;
    }
    unique->initSlots = slots;
    shift = sizeof(int) * 8 - cuddComputeFloorLog2(slots);

    unique->slots = (numVars + numVarsZ + 1) * slots;
    unique->keys = 0;
    unique->maxLive = ~0;       /* very large number */
    unique->keysZ = 0;
    unique->dead = 0;
    unique->deadZ = 0;
    unique->gcFrac = DD_GC_FRAC_HI;
    unique->minDead = (unsigned) (DD_GC_FRAC_HI * (double) unique->slots);
    unique->looseUpTo = looseUpTo;
    unique->gcEnabled = 1;
    unique->allocated = 0;
    unique->reclaimed = 0;
    unique->subtables = ALLOC(DdSubtable,unique->maxSize);
    if (unique->subtables == NULL) {
        FREE(unique);
        return(NULL);
    }
    unique->subtableZ = ALLOC(DdSubtable,unique->maxSizeZ);
    if (unique->subtableZ == NULL) {
        FREE(unique->subtables);
        FREE(unique);
        return(NULL);
    }
    unique->perm = ALLOC(int,unique->maxSize);
    if (unique->perm == NULL) {
        FREE(unique->subtables);
        FREE(unique->subtableZ);
        FREE(unique);
        return(NULL);
    }
    unique->invperm = ALLOC(int,unique->maxSize);
    if (unique->invperm == NULL) {
        FREE(unique->subtables);
        FREE(unique->subtableZ);
        FREE(unique->perm);
        FREE(unique);
        return(NULL);
    }
    unique->permZ = ALLOC(int,unique->maxSizeZ);
    if (unique->permZ == NULL) {
        FREE(unique->subtables);
        FREE(unique->subtableZ);
        FREE(unique->perm);
        FREE(unique->invperm);
        FREE(unique);
        return(NULL);
    }
    unique->invpermZ = ALLOC(int,unique->maxSizeZ);
    if (unique->invpermZ == NULL) {
        FREE(unique->subtables);
        FREE(unique->subtableZ);
        FREE(unique->perm);
        FREE(unique->invperm);
        FREE(unique->permZ);
        FREE(unique);
        return(NULL);
    }
    unique->map = NULL;
    unique->stack = ALLOC(DdNodePtr,ddMax(unique->maxSize,unique->maxSizeZ)+1);
    if (unique->stack == NULL) {
        FREE(unique->subtables);
        FREE(unique->subtableZ);
        FREE(unique->perm);
        FREE(unique->invperm);
        FREE(unique->permZ);
        FREE(unique->invpermZ);
        FREE(unique);
        return(NULL);
    }
    unique->stack[0] = NULL; /* to suppress harmless UMR */

#ifndef DD_NO_DEATH_ROW
    unique->deathRowDepth = 1 << cuddComputeFloorLog2(unique->looseUpTo >> 2);
    unique->deathRow = ALLOC(DdNodePtr,unique->deathRowDepth);
    if (unique->deathRow == NULL) {
        FREE(unique->subtables);
        FREE(unique->subtableZ);
        FREE(unique->perm);
        FREE(unique->invperm);
        FREE(unique->permZ);
        FREE(unique->invpermZ);
        FREE(unique->stack);
        FREE(unique);
        return(NULL);
    }
    for (i = 0; i < unique->deathRowDepth; i++) {
        unique->deathRow[i] = NULL;
    }
    unique->nextDead = 0;
    unique->deadMask = unique->deathRowDepth - 1;
#endif

    for (i = 0; (unsigned) i < numVars; i++) {
        unique->subtables[i].slots = slots;
        unique->subtables[i].shift = shift;
        unique->subtables[i].keys = 0;
        unique->subtables[i].dead = 0;
        unique->subtables[i].maxKeys = slots * DD_MAX_SUBTABLE_DENSITY;
        unique->subtables[i].bindVar = 0;
        unique->subtables[i].varType = CUDD_VAR_PRIMARY_INPUT;
        unique->subtables[i].pairIndex = 0;
        unique->subtables[i].varHandled = 0;
        unique->subtables[i].varToBeGrouped = CUDD_LAZY_NONE;

        nodelist = unique->subtables[i].nodelist = ALLOC(DdNodePtr,slots);
        if (nodelist == NULL) {
            for (j = 0; j < i; j++) {
                FREE(unique->subtables[j].nodelist);
            }
            FREE(unique->subtables);
            FREE(unique->subtableZ);
            FREE(unique->perm);
            FREE(unique->invperm);
            FREE(unique->permZ);
            FREE(unique->invpermZ);
            FREE(unique->stack);
            FREE(unique);
            return(NULL);
        }
        for (j = 0; (unsigned) j < slots; j++) {
            nodelist[j] = sentinel;
        }
        unique->perm[i] = i;
        unique->invperm[i] = i;
    }
    for (i = 0; (unsigned) i < numVarsZ; i++) {
        unique->subtableZ[i].slots = slots;
        unique->subtableZ[i].shift = shift;
        unique->subtableZ[i].keys = 0;
        unique->subtableZ[i].dead = 0;
        unique->subtableZ[i].maxKeys = slots * DD_MAX_SUBTABLE_DENSITY;
        nodelist = unique->subtableZ[i].nodelist = ALLOC(DdNodePtr,slots);
        if (nodelist == NULL) {
            for (j = 0; (unsigned) j < numVars; j++) {
                FREE(unique->subtables[j].nodelist);
            }
            FREE(unique->subtables);
            for (j = 0; j < i; j++) {
                FREE(unique->subtableZ[j].nodelist);
            }
            FREE(unique->subtableZ);
            FREE(unique->perm);
            FREE(unique->invperm);
            FREE(unique->permZ);
            FREE(unique->invpermZ);
            FREE(unique->stack);
            FREE(unique);
            return(NULL);
        }
        for (j = 0; (unsigned) j < slots; j++) {
            nodelist[j] = NULL;
        }
        unique->permZ[i] = i;
        unique->invpermZ[i] = i;
    }
    unique->constants.slots = slots;
    unique->constants.shift = shift;
    unique->constants.keys = 0;
    unique->constants.dead = 0;
    unique->constants.maxKeys = slots * DD_MAX_SUBTABLE_DENSITY;
    nodelist = unique->constants.nodelist = ALLOC(DdNodePtr,slots);
    if (nodelist == NULL) {
        for (j = 0; (unsigned) j < numVars; j++) {
            FREE(unique->subtables[j].nodelist);
        }
        FREE(unique->subtables);
        for (j = 0; (unsigned) j < numVarsZ; j++) {
            FREE(unique->subtableZ[j].nodelist);
        }
        FREE(unique->subtableZ);
        FREE(unique->perm);
        FREE(unique->invperm);
        FREE(unique->permZ);
        FREE(unique->invpermZ);
        FREE(unique->stack);
        FREE(unique);
        return(NULL);
    }
    for (j = 0; (unsigned) j < slots; j++) {
        nodelist[j] = NULL;
    }

    unique->memoryList = NULL;
    unique->nextFree = NULL;

    unique->memused = sizeof(DdManager) + (unique->maxSize + unique->maxSizeZ)
        * (sizeof(DdSubtable) + 2 * sizeof(int)) + (numVars + 1) *
        slots * sizeof(DdNodePtr) +
        (ddMax(unique->maxSize,unique->maxSizeZ) + 1) * sizeof(DdNodePtr);
#ifndef DD_NO_DEATH_ROW
    unique->memused += unique->deathRowDepth * sizeof(DdNodePtr);
#endif

    /* Initialize fields concerned with automatic dynamic reordering */
    unique->reorderings = 0;
    unique->autoDyn = 0;        /* initially disabled */
    unique->autoDynZ = 0;       /* initially disabled */
    unique->realign = 0;        /* initially disabled */
    unique->realignZ = 0;       /* initially disabled */
    unique->reordered = 0;
    unique->autoMethod = CUDD_REORDER_SIFT;
    unique->autoMethodZ = CUDD_REORDER_SIFT;
    unique->nextDyn = DD_FIRST_REORDER;
    unique->countDead = ~0;
    unique->siftMaxVar = DD_SIFT_MAX_VAR;
    unique->siftMaxSwap = DD_SIFT_MAX_SWAPS;
    unique->tree = NULL;
    unique->treeZ = NULL;
    unique->groupcheck = CUDD_GROUP_CHECK7;
    unique->recomb = DD_DEFAULT_RECOMB;
    unique->symmviolation = 0;
    unique->arcviolation = 0;
    unique->populationSize = 0;
    unique->numberXovers = 0;
    unique->linear = NULL;
    unique->linearSize = 0;

    /* Initialize ZDD universe. */
    unique->univ = (DdNodePtr *)NULL;

    /* Initialize auxiliary fields. */
    unique->localCaches = NULL;
    unique->preGCHook = NULL;
    unique->postGCHook = NULL;
    unique->preReorderingHook = NULL;
    unique->postReorderingHook = NULL;
    unique->out = stdout;
    unique->err = stderr;
    unique->errorCode = CUDD_NO_ERROR;

    /* Initialize statistical counters. */
    unique->maxmemhard = ~ 0UL;
    unique->garbageCollections = 0;
    unique->GCTime = 0;
    unique->reordTime = 0;
#ifdef DD_STATS
    unique->nodesDropped = 0;
    unique->nodesFreed = 0;
#endif
    unique->peakLiveNodes = 0;
#ifdef DD_UNIQUE_PROFILE
    unique->uniqueLookUps = 0;
    unique->uniqueLinks = 0;
#endif
#ifdef DD_COUNT
    unique->recursiveCalls = 0;
    unique->swapSteps = 0;
#ifdef DD_STATS
    unique->nextSample = 250000;
#endif
#endif

    return(unique);

} /* end of cuddInitTable */

int cuddInsertSubtables	(	DdManager *	unique,
		int	n,
		int	level
	)

Function********************************************************************

Synopsis [Inserts n new subtables in a unique table at level.]

Description [Inserts n new subtables in a unique table at level. The number n should be positive, and level should be an existing level. Returns 1 if successful; 0 otherwise.]

SideEffects [None]

SeeAlso [cuddDestroySubtables]

Definition at line 1780 of file cuddTable.c.

{
    DdSubtable *newsubtables;
    DdNodePtr *newnodelist;
    DdNodePtr *newvars;
    DdNode *sentinel = &(unique->sentinel);
    int oldsize,newsize;
    int i,j,index,reorderSave;
    unsigned int numSlots = unique->initSlots;
    int *newperm, *newinvperm, *newmap;
    DdNode *one, *zero;

#ifdef DD_DEBUG
    assert(n > 0 && level < unique->size);
#endif

    oldsize = unique->size;
    /* Easy case: there is still room in the current table. */
    if (oldsize + n <= unique->maxSize) {
        /* Shift the tables at and below level. */
        for (i = oldsize - 1; i >= level; i--) {
            unique->subtables[i+n].slots    = unique->subtables[i].slots;
            unique->subtables[i+n].shift    = unique->subtables[i].shift;
            unique->subtables[i+n].keys     = unique->subtables[i].keys;
            unique->subtables[i+n].maxKeys  = unique->subtables[i].maxKeys;
            unique->subtables[i+n].dead     = unique->subtables[i].dead;
            unique->subtables[i+n].nodelist = unique->subtables[i].nodelist;
            unique->subtables[i+n].bindVar  = unique->subtables[i].bindVar;
            unique->subtables[i+n].varType  = unique->subtables[i].varType;
            unique->subtables[i+n].pairIndex  = unique->subtables[i].pairIndex;
            unique->subtables[i+n].varHandled = unique->subtables[i].varHandled;
            unique->subtables[i+n].varToBeGrouped =
                unique->subtables[i].varToBeGrouped;

            index                           = unique->invperm[i];
            unique->invperm[i+n]            = index;
            unique->perm[index]            += n;
        }
        /* Create new subtables. */
        for (i = 0; i < n; i++) {
            unique->subtables[level+i].slots = numSlots;
            unique->subtables[level+i].shift = sizeof(int) * 8 -
                cuddComputeFloorLog2(numSlots);
            unique->subtables[level+i].keys = 0;
            unique->subtables[level+i].maxKeys = numSlots * DD_MAX_SUBTABLE_DENSITY;
            unique->subtables[level+i].dead = 0;
            unique->subtables[level+i].bindVar = 0;
            unique->subtables[level+i].varType = CUDD_VAR_PRIMARY_INPUT;
            unique->subtables[level+i].pairIndex = 0;
            unique->subtables[level+i].varHandled = 0;
            unique->subtables[level+i].varToBeGrouped = CUDD_LAZY_NONE;

            unique->perm[oldsize+i] = level + i;
            unique->invperm[level+i] = oldsize + i;
            newnodelist = unique->subtables[level+i].nodelist =
                ALLOC(DdNodePtr, numSlots);
            if (newnodelist == NULL) {
                unique->errorCode = CUDD_MEMORY_OUT;
                return(0);
            }
            for (j = 0; (unsigned) j < numSlots; j++) {
                newnodelist[j] = sentinel;
            }
        }
        if (unique->map != NULL) {
            for (i = 0; i < n; i++) {
                unique->map[oldsize+i] = oldsize + i;
            }
        }
    } else {
        /* The current table is too small: we need to allocate a new,
        ** larger one; move all old subtables, and initialize the new
        ** subtables.
        */
        newsize = oldsize + n + DD_DEFAULT_RESIZE;
#ifdef DD_VERBOSE
        (void) fprintf(unique->err,
                       "Increasing the table size from %d to %d\n",
            unique->maxSize, newsize);
#endif
        /* Allocate memory for new arrays (except nodelists). */
        newsubtables = ALLOC(DdSubtable,newsize);
        if (newsubtables == NULL) {
            unique->errorCode = CUDD_MEMORY_OUT;
            return(0);
        }
        newvars = ALLOC(DdNodePtr,newsize);
        if (newvars == NULL) {
            unique->errorCode = CUDD_MEMORY_OUT;
            FREE(newsubtables);
            return(0);
        }
        newperm = ALLOC(int,newsize);
        if (newperm == NULL) {
            unique->errorCode = CUDD_MEMORY_OUT;
            FREE(newsubtables);
            FREE(newvars);
            return(0);
        }
        newinvperm = ALLOC(int,newsize);
        if (newinvperm == NULL) {
            unique->errorCode = CUDD_MEMORY_OUT;
            FREE(newsubtables);
            FREE(newvars);
            FREE(newperm);
            return(0);
        }
        if (unique->map != NULL) {
            newmap = ALLOC(int,newsize);
            if (newmap == NULL) {
                unique->errorCode = CUDD_MEMORY_OUT;
                FREE(newsubtables);
                FREE(newvars);
                FREE(newperm);
                FREE(newinvperm);
                return(0);
            }
            unique->memused += (newsize - unique->maxSize) * sizeof(int);
        }
        unique->memused += (newsize - unique->maxSize) * ((numSlots+1) *
            sizeof(DdNode *) + 2 * sizeof(int) + sizeof(DdSubtable));
        /* Copy levels before insertion points from old tables. */
        for (i = 0; i < level; i++) {
            newsubtables[i].slots = unique->subtables[i].slots;
            newsubtables[i].shift = unique->subtables[i].shift;
            newsubtables[i].keys = unique->subtables[i].keys;
            newsubtables[i].maxKeys = unique->subtables[i].maxKeys;
            newsubtables[i].dead = unique->subtables[i].dead;
            newsubtables[i].nodelist = unique->subtables[i].nodelist;
            newsubtables[i].bindVar = unique->subtables[i].bindVar;
            newsubtables[i].varType = unique->subtables[i].varType;
            newsubtables[i].pairIndex = unique->subtables[i].pairIndex;
            newsubtables[i].varHandled = unique->subtables[i].varHandled;
            newsubtables[i].varToBeGrouped = unique->subtables[i].varToBeGrouped;

            newvars[i] = unique->vars[i];
            newperm[i] = unique->perm[i];
            newinvperm[i] = unique->invperm[i];
        }
        /* Finish initializing permutation for new table to old one. */
        for (i = level; i < oldsize; i++) {
            newperm[i] = unique->perm[i];
        }
        /* Initialize new levels. */
        for (i = level; i < level + n; i++) {
            newsubtables[i].slots = numSlots;
            newsubtables[i].shift = sizeof(int) * 8 -
                cuddComputeFloorLog2(numSlots);
            newsubtables[i].keys = 0;
            newsubtables[i].maxKeys = numSlots * DD_MAX_SUBTABLE_DENSITY;
            newsubtables[i].dead = 0;
            newsubtables[i].bindVar = 0;
            newsubtables[i].varType = CUDD_VAR_PRIMARY_INPUT;
            newsubtables[i].pairIndex = 0;
            newsubtables[i].varHandled = 0;
            newsubtables[i].varToBeGrouped = CUDD_LAZY_NONE;

            newperm[oldsize + i - level] = i;
            newinvperm[i] = oldsize + i - level;
            newnodelist = newsubtables[i].nodelist = ALLOC(DdNodePtr, numSlots);
            if (newnodelist == NULL) {
                /* We are going to leak some memory.  We should clean up. */
                unique->errorCode = CUDD_MEMORY_OUT;
                return(0);
            }
            for (j = 0; (unsigned) j < numSlots; j++) {
                newnodelist[j] = sentinel;
            }
        }
        /* Copy the old tables for levels past the insertion point. */
        for (i = level; i < oldsize; i++) {
            newsubtables[i+n].slots    = unique->subtables[i].slots;
            newsubtables[i+n].shift    = unique->subtables[i].shift;
            newsubtables[i+n].keys     = unique->subtables[i].keys;
            newsubtables[i+n].maxKeys  = unique->subtables[i].maxKeys;
            newsubtables[i+n].dead     = unique->subtables[i].dead;
            newsubtables[i+n].nodelist = unique->subtables[i].nodelist;
            newsubtables[i+n].bindVar  = unique->subtables[i].bindVar;
            newsubtables[i+n].varType  = unique->subtables[i].varType;
            newsubtables[i+n].pairIndex  = unique->subtables[i].pairIndex;
            newsubtables[i+n].varHandled  = unique->subtables[i].varHandled;
            newsubtables[i+n].varToBeGrouped  =
                unique->subtables[i].varToBeGrouped;

            newvars[i]                 = unique->vars[i];
            index                      = unique->invperm[i];
            newinvperm[i+n]            = index;
            newperm[index]            += n;
        }
        /* Update the map. */
        if (unique->map != NULL) {
            for (i = 0; i < oldsize; i++) {
                newmap[i] = unique->map[i];
            }
            for (i = oldsize; i < oldsize + n; i++) {
                newmap[i] = i;
            }
            FREE(unique->map);
            unique->map = newmap;
        }
        /* Install the new tables and free the old ones. */
        FREE(unique->subtables);
        unique->subtables = newsubtables;
        unique->maxSize = newsize;
        FREE(unique->vars);
        unique->vars = newvars;
        FREE(unique->perm);
        unique->perm = newperm;
        FREE(unique->invperm);
        unique->invperm = newinvperm;
        /* Update the stack for iterative procedures. */
        if (newsize > unique->maxSizeZ) {
            FREE(unique->stack);
            unique->stack = ALLOC(DdNodePtr,newsize + 1);
            if (unique->stack == NULL) {
                unique->errorCode = CUDD_MEMORY_OUT;
                return(0);
            }
            unique->stack[0] = NULL; /* to suppress harmless UMR */
            unique->memused +=
                (newsize - ddMax(unique->maxSize,unique->maxSizeZ))
                * sizeof(DdNode *);
        }
    }
    /* Update manager parameters to account for the new subtables. */
    unique->slots += n * numSlots;
    ddFixLimits(unique);
    unique->size += n;

    /* Now that the table is in a coherent state, create the new
    ** projection functions. We need to temporarily disable reordering,
    ** because we cannot reorder without projection functions in place.
    **/
    one = unique->one;
    zero = Cudd_Not(one);

    reorderSave = unique->autoDyn;
    unique->autoDyn = 0;
    for (i = oldsize; i < oldsize + n; i++) {
        unique->vars[i] = cuddUniqueInter(unique,i,one,zero);
        if (unique->vars[i] == NULL) {
            unique->autoDyn = reorderSave;
            /* Shift everything back so table remains coherent. */
            for (j = oldsize; j < i; j++) {
                Cudd_IterDerefBdd(unique,unique->vars[j]);
                cuddDeallocNode(unique,unique->vars[j]);
                unique->vars[j] = NULL;
            }
            for (j = level; j < oldsize; j++) {
                unique->subtables[j].slots    = unique->subtables[j+n].slots;
                unique->subtables[j].slots    = unique->subtables[j+n].slots;
                unique->subtables[j].shift    = unique->subtables[j+n].shift;
                unique->subtables[j].keys     = unique->subtables[j+n].keys;
                unique->subtables[j].maxKeys  =
                    unique->subtables[j+n].maxKeys;
                unique->subtables[j].dead     = unique->subtables[j+n].dead;
                FREE(unique->subtables[j].nodelist);
                unique->subtables[j].nodelist =
                    unique->subtables[j+n].nodelist;
                unique->subtables[j+n].nodelist = NULL;
                unique->subtables[j].bindVar  =
                    unique->subtables[j+n].bindVar;
                unique->subtables[j].varType  =
                    unique->subtables[j+n].varType;
                unique->subtables[j].pairIndex =
                    unique->subtables[j+n].pairIndex;
                unique->subtables[j].varHandled =
                    unique->subtables[j+n].varHandled;
                unique->subtables[j].varToBeGrouped =
                    unique->subtables[j+n].varToBeGrouped;
                index                         = unique->invperm[j+n];
                unique->invperm[j]            = index;
                unique->perm[index]          -= n;
            }
            unique->size = oldsize;
            unique->slots -= n * numSlots;
            ddFixLimits(unique);
            (void) Cudd_DebugCheck(unique);
            return(0);
        }
        cuddRef(unique->vars[i]);
    }
    if (unique->tree != NULL) {
        unique->tree->size += n;
        unique->tree->index = unique->invperm[0];
        ddPatchTree(unique,unique->tree);
    }
    unique->autoDyn = reorderSave;

    return(1);

} /* end of cuddInsertSubtables */

void cuddRehash	(	DdManager *	unique,
		int	i
	)

Function********************************************************************

Synopsis [Rehashes a unique subtable.]

Description [Doubles the size of a unique subtable and rehashes its contents.]

SideEffects [None]

SeeAlso []

Definition at line 1515 of file cuddTable.c.

{
    unsigned int slots, oldslots;
    int shift, oldshift;
    int j, pos;
    DdNodePtr *nodelist, *oldnodelist;
    DdNode *node, *next;
    DdNode *sentinel = &(unique->sentinel);
    hack split;
    extern DD_OOMFP MMoutOfMemory;
    DD_OOMFP saveHandler;

    if (unique->gcFrac == DD_GC_FRAC_HI && unique->slots > unique->looseUpTo) {
        unique->gcFrac = DD_GC_FRAC_LO;
        unique->minDead = (unsigned) (DD_GC_FRAC_LO * (double) unique->slots);
#ifdef DD_VERBOSE
        (void) fprintf(unique->err,"GC fraction = %.2f\t", DD_GC_FRAC_LO);
        (void) fprintf(unique->err,"minDead = %d\n", unique->minDead);
#endif
    }

    if (unique->gcFrac != DD_GC_FRAC_MIN && unique->memused > unique->maxmem) {
        unique->gcFrac = DD_GC_FRAC_MIN;
        unique->minDead = (unsigned) (DD_GC_FRAC_MIN * (double) unique->slots);
#ifdef DD_VERBOSE
        (void) fprintf(unique->err,"GC fraction = %.2f\t", DD_GC_FRAC_MIN);
        (void) fprintf(unique->err,"minDead = %d\n", unique->minDead);
#endif
        cuddShrinkDeathRow(unique);
        if (cuddGarbageCollect(unique,1) > 0) return;
    }

    if (i != CUDD_CONST_INDEX) {
        oldslots = unique->subtables[i].slots;
        oldshift = unique->subtables[i].shift;
        oldnodelist = unique->subtables[i].nodelist;

        /* Compute the new size of the subtable. */
        slots = oldslots << 1;
        shift = oldshift - 1;

        saveHandler = MMoutOfMemory;
        MMoutOfMemory = Cudd_OutOfMem;
        nodelist = ALLOC(DdNodePtr, slots);
        MMoutOfMemory = saveHandler;
        if (nodelist == NULL) {
            (void) fprintf(unique->err,
                           "Unable to resize subtable %d for lack of memory\n",
                           i);
            /* Prevent frequent resizing attempts. */
            (void) cuddGarbageCollect(unique,1);
            if (unique->stash != NULL) {
                FREE(unique->stash);
                unique->stash = NULL;
                /* Inhibit resizing of tables. */
                cuddSlowTableGrowth(unique);
            }
            return;
        }
        unique->subtables[i].nodelist = nodelist;
        unique->subtables[i].slots = slots;
        unique->subtables[i].shift = shift;
        unique->subtables[i].maxKeys = slots * DD_MAX_SUBTABLE_DENSITY;

        /* Move the nodes from the old table to the new table.
        ** This code depends on the type of hash function.
        ** It assumes that the effect of doubling the size of the table
        ** is to retain one more bit of the 32-bit hash value.
        ** The additional bit is the LSB. */
        for (j = 0; (unsigned) j < oldslots; j++) {
            DdNodePtr *evenP, *oddP;
            node = oldnodelist[j];
            evenP = &(nodelist[j<<1]);
            oddP = &(nodelist[(j<<1)+1]);
            while (node != sentinel) {
                next = node->next;
                pos = ddHash(cuddT(node), cuddE(node), shift);
                if (pos & 1) {
                    *oddP = node;
                    oddP = &(node->next);
                } else {
                    *evenP = node;
                    evenP = &(node->next);
                }
                node = next;
            }
            *evenP = *oddP = sentinel;
        }
        FREE(oldnodelist);

#ifdef DD_VERBOSE
        (void) fprintf(unique->err,
                       "rehashing layer %d: keys %d dead %d new size %d\n",
                       i, unique->subtables[i].keys,
                       unique->subtables[i].dead, slots);
#endif
    } else {
        oldslots = unique->constants.slots;
        oldshift = unique->constants.shift;
        oldnodelist = unique->constants.nodelist;

        /* The constant subtable is never subjected to reordering.
        ** Therefore, when it is resized, it is because it has just
        ** reached the maximum load. We can safely just double the size,
        ** with no need for the loop we use for the other tables.
        */
        slots = oldslots << 1;
        shift = oldshift - 1;
        saveHandler = MMoutOfMemory;
        MMoutOfMemory = Cudd_OutOfMem;
        nodelist = ALLOC(DdNodePtr, slots);
        MMoutOfMemory = saveHandler;
        if (nodelist == NULL) {
            (void) fprintf(unique->err,
                           "Unable to resize constant subtable for lack of memory\n");
            (void) cuddGarbageCollect(unique,1);
            for (j = 0; j < unique->size; j++) {
                unique->subtables[j].maxKeys <<= 1;
            }
            unique->constants.maxKeys <<= 1;
            return;
        }
        unique->constants.slots = slots;
        unique->constants.shift = shift;
        unique->constants.maxKeys = slots * DD_MAX_SUBTABLE_DENSITY;
        unique->constants.nodelist = nodelist;
        for (j = 0; (unsigned) j < slots; j++) {
            nodelist[j] = NULL;
        }
        for (j = 0; (unsigned) j < oldslots; j++) {
            node = oldnodelist[j];
            while (node != NULL) {
                next = node->next;
                split.value = cuddV(node);
                pos = ddHash(split.bits[0], split.bits[1], shift);
                node->next = nodelist[pos];
                nodelist[pos] = node;
                node = next;
            }
        }
        FREE(oldnodelist);

#ifdef DD_VERBOSE
        (void) fprintf(unique->err,
                       "rehashing constants: keys %d dead %d new size %d\n",
                       unique->constants.keys,unique->constants.dead,slots);
#endif
    }

    /* Update global data */

    unique->memused += (slots - oldslots) * sizeof(DdNodePtr);
    unique->slots += (slots - oldslots);
    ddFixLimits(unique);

} /* end of cuddRehash */

int cuddResizeTableZdd	(	DdManager *	unique,
		int	index
	)

Function********************************************************************

Synopsis [Increases the number of ZDD subtables in a unique table so that it meets or exceeds index.]

Description [Increases the number of ZDD subtables in a unique table so that it meets or exceeds index. When new ZDD variables are created, it is possible to preserve the functions unchanged, or it is possible to preserve the covers unchanged, but not both. cuddResizeTableZdd preserves the covers. Returns 1 if successful; 0 otherwise.]

SideEffects [None]

SeeAlso [ddResizeTable]

Definition at line 2226 of file cuddTable.c.

{
    DdSubtable *newsubtables;
    DdNodePtr *newnodelist;
    int oldsize,newsize;
    int i,j,reorderSave;
    unsigned int numSlots = unique->initSlots;
    int *newperm, *newinvperm;

    oldsize = unique->sizeZ;
    /* Easy case: there is still room in the current table. */
    if (index < unique->maxSizeZ) {
        for (i = oldsize; i <= index; i++) {
            unique->subtableZ[i].slots = numSlots;
            unique->subtableZ[i].shift = sizeof(int) * 8 -
                cuddComputeFloorLog2(numSlots);
            unique->subtableZ[i].keys = 0;
            unique->subtableZ[i].maxKeys = numSlots * DD_MAX_SUBTABLE_DENSITY;
            unique->subtableZ[i].dead = 0;
            unique->permZ[i] = i;
            unique->invpermZ[i] = i;
            newnodelist = unique->subtableZ[i].nodelist =
                ALLOC(DdNodePtr, numSlots);
            if (newnodelist == NULL) {
                unique->errorCode = CUDD_MEMORY_OUT;
                return(0);
            }
            for (j = 0; (unsigned) j < numSlots; j++) {
                newnodelist[j] = NULL;
            }
        }
    } else {
        /* The current table is too small: we need to allocate a new,
        ** larger one; move all old subtables, and initialize the new
        ** subtables up to index included.
        */
        newsize = index + DD_DEFAULT_RESIZE;
#ifdef DD_VERBOSE
        (void) fprintf(unique->err,
                       "Increasing the ZDD table size from %d to %d\n",
            unique->maxSizeZ, newsize);
#endif
        newsubtables = ALLOC(DdSubtable,newsize);
        if (newsubtables == NULL) {
            unique->errorCode = CUDD_MEMORY_OUT;
            return(0);
        }
        newperm = ALLOC(int,newsize);
        if (newperm == NULL) {
            unique->errorCode = CUDD_MEMORY_OUT;
            return(0);
        }
        newinvperm = ALLOC(int,newsize);
        if (newinvperm == NULL) {
            unique->errorCode = CUDD_MEMORY_OUT;
            return(0);
        }
        unique->memused += (newsize - unique->maxSizeZ) * ((numSlots+1) *
            sizeof(DdNode *) + 2 * sizeof(int) + sizeof(DdSubtable));
        if (newsize > unique->maxSize) {
            FREE(unique->stack);
            unique->stack = ALLOC(DdNodePtr,newsize + 1);
            if (unique->stack == NULL) {
                unique->errorCode = CUDD_MEMORY_OUT;
                return(0);
            }
            unique->stack[0] = NULL; /* to suppress harmless UMR */
            unique->memused +=
                (newsize - ddMax(unique->maxSize,unique->maxSizeZ))
                * sizeof(DdNode *);
        }
        for (i = 0; i < oldsize; i++) {
            newsubtables[i].slots = unique->subtableZ[i].slots;
            newsubtables[i].shift = unique->subtableZ[i].shift;
            newsubtables[i].keys = unique->subtableZ[i].keys;
            newsubtables[i].maxKeys = unique->subtableZ[i].maxKeys;
            newsubtables[i].dead = unique->subtableZ[i].dead;
            newsubtables[i].nodelist = unique->subtableZ[i].nodelist;
            newperm[i] = unique->permZ[i];
            newinvperm[i] = unique->invpermZ[i];
        }
        for (i = oldsize; i <= index; i++) {
            newsubtables[i].slots = numSlots;
            newsubtables[i].shift = sizeof(int) * 8 -
                cuddComputeFloorLog2(numSlots);
            newsubtables[i].keys = 0;
            newsubtables[i].maxKeys = numSlots * DD_MAX_SUBTABLE_DENSITY;
            newsubtables[i].dead = 0;
            newperm[i] = i;
            newinvperm[i] = i;
            newnodelist = newsubtables[i].nodelist = ALLOC(DdNodePtr, numSlots);
            if (newnodelist == NULL) {
                unique->errorCode = CUDD_MEMORY_OUT;
                return(0);
            }
            for (j = 0; (unsigned) j < numSlots; j++) {
                newnodelist[j] = NULL;
            }
        }
        FREE(unique->subtableZ);
        unique->subtableZ = newsubtables;
        unique->maxSizeZ = newsize;
        FREE(unique->permZ);
        unique->permZ = newperm;
        FREE(unique->invpermZ);
        unique->invpermZ = newinvperm;
    }
    unique->slots += (index + 1 - unique->sizeZ) * numSlots;
    ddFixLimits(unique);
    unique->sizeZ = index + 1;

    /* Now that the table is in a coherent state, update the ZDD
    ** universe. We need to temporarily disable reordering,
    ** because we cannot reorder without universe in place.
    */

    reorderSave = unique->autoDynZ;
    unique->autoDynZ = 0;
    cuddZddFreeUniv(unique);
    if (!cuddZddInitUniv(unique)) {
        unique->autoDynZ = reorderSave;
        return(0);
    }
    unique->autoDynZ = reorderSave;

    return(1);

} /* end of cuddResizeTableZdd */

void cuddShrinkSubtable	(	DdManager *	unique,
		int	i
	)

Function********************************************************************

Synopsis [Shrinks a subtable.]

Description [Shrinks a subtable.]

SideEffects [None]

SeeAlso [cuddRehash]

Definition at line 1687 of file cuddTable.c.

{
    int j;
    int shift, posn;
    DdNodePtr *nodelist, *oldnodelist;
    DdNode *node, *next;
    DdNode *sentinel = &(unique->sentinel);
    unsigned int slots, oldslots;
    extern DD_OOMFP MMoutOfMemory;
    DD_OOMFP saveHandler;

    oldnodelist = unique->subtables[i].nodelist;
    oldslots = unique->subtables[i].slots;
    slots = oldslots >> 1;
    saveHandler = MMoutOfMemory;
    MMoutOfMemory = Cudd_OutOfMem;
    nodelist = ALLOC(DdNodePtr, slots);
    MMoutOfMemory = saveHandler;
    if (nodelist == NULL) {
        return;
    }
    unique->subtables[i].nodelist = nodelist;
    unique->subtables[i].slots = slots;
    unique->subtables[i].shift++;
    unique->subtables[i].maxKeys = slots * DD_MAX_SUBTABLE_DENSITY;
#ifdef DD_VERBOSE
    (void) fprintf(unique->err,
                   "shrunk layer %d (%d keys) from %d to %d slots\n",
                   i, unique->subtables[i].keys, oldslots, slots);
#endif

    for (j = 0; (unsigned) j < slots; j++) {
        nodelist[j] = sentinel;
    }
    shift = unique->subtables[i].shift;
    for (j = 0; (unsigned) j < oldslots; j++) {
        node = oldnodelist[j];
        while (node != sentinel) {
            DdNode *looking, *T, *E;
            DdNodePtr *previousP;
            next = node->next;
            posn = ddHash(cuddT(node), cuddE(node), shift);
            previousP = &(nodelist[posn]);
            looking = *previousP;
            T = cuddT(node);
            E = cuddE(node);
            while (T < cuddT(looking)) {
                previousP = &(looking->next);
                looking = *previousP;
#ifdef DD_UNIQUE_PROFILE
                unique->uniqueLinks++;
#endif
            }
            while (T == cuddT(looking) && E < cuddE(looking)) {
                previousP = &(looking->next);
                looking = *previousP;
#ifdef DD_UNIQUE_PROFILE
                unique->uniqueLinks++;
#endif
            }
            node->next = *previousP;
            *previousP = node;
            node = next;
        }
    }
    FREE(oldnodelist);

    unique->memused += ((long) slots - (long) oldslots) * sizeof(DdNode *);
    unique->slots += slots - oldslots;
    unique->minDead = (unsigned) (unique->gcFrac * (double) unique->slots);
    unique->cacheSlack = (int)
        ddMin(unique->maxCacheHard,DD_MAX_CACHE_TO_SLOTS_RATIO * unique->slots)
        - 2 * (int) unique->cacheSlots;

} /* end of cuddShrinkSubtable */

void cuddSlowTableGrowth

(

DdManager *

unique

)

Function********************************************************************

Synopsis [Adjusts parameters of a table to slow down its growth.]

Description []

SideEffects [None]

SeeAlso []

Definition at line 2370 of file cuddTable.c.

{
    int i;

    unique->maxCacheHard = unique->cacheSlots - 1;
    unique->cacheSlack = - (int) (unique->cacheSlots + 1);
    for (i = 0; i < unique->size; i++) {
        unique->subtables[i].maxKeys <<= 2;
    }
    unique->gcFrac = DD_GC_FRAC_MIN;
    unique->minDead = (unsigned) (DD_GC_FRAC_MIN * (double) unique->slots);
    cuddShrinkDeathRow(unique);
    (void) fprintf(unique->err,"Slowing down table growth: ");
    (void) fprintf(unique->err,"GC fraction = %.2f\t", unique->gcFrac);
    (void) fprintf(unique->err,"minDead = %u\n", unique->minDead);

} /* end of cuddSlowTableGrowth */

DdNode* cuddUniqueConst	(	DdManager *	unique,
		CUDD_VALUE_TYPE	value
	)

Function********************************************************************

Synopsis [Checks the unique table for the existence of a constant node.]

Description [Checks the unique table for the existence of a constant node. If it does not exist, it creates a new one. Does not modify the reference count of whatever is returned. A newly created internal node comes back with a reference count 0. Returns a pointer to the new node.]

SideEffects [None]

Definition at line 1435 of file cuddTable.c.

{
    int pos;
    DdNodePtr *nodelist;
    DdNode *looking;
    hack split;

#ifdef DD_UNIQUE_PROFILE
    unique->uniqueLookUps++;
#endif

    if (unique->constants.keys > unique->constants.maxKeys) {
        if (unique->gcEnabled && ((unique->dead > unique->minDead) ||
        (10 * unique->constants.dead > 9 * unique->constants.keys))) {  /* too many dead */
            (void) cuddGarbageCollect(unique,1);
        } else {
            cuddRehash(unique,CUDD_CONST_INDEX);
        }
    }

    cuddAdjust(value); /* for the case of crippled infinities */

    if (ddAbs(value) < unique->epsilon) {
        value = 0.0;
    }
    split.value = value;

    pos = ddHash(split.bits[0], split.bits[1], unique->constants.shift);
    nodelist = unique->constants.nodelist;
    looking = nodelist[pos];

    /* Here we compare values both for equality and for difference less
     * than epsilon. The first comparison is required when values are
     * infinite, since Infinity - Infinity is NaN and NaN < X is 0 for
     * every X.
     */
    while (looking != NULL) {
        if (looking->type.value == value ||
        ddEqualVal(looking->type.value,value,unique->epsilon)) {
            if (looking->ref == 0) {
                cuddReclaim(unique,looking);
            }
            return(looking);
        }
        looking = looking->next;
#ifdef DD_UNIQUE_PROFILE
        unique->uniqueLinks++;
#endif
    }

    unique->keys++;
    unique->constants.keys++;

    looking = cuddAllocNode(unique);
    if (looking == NULL) return(NULL);
    looking->index = CUDD_CONST_INDEX;
    looking->type.value = value;
    looking->next = nodelist[pos];
    nodelist[pos] = looking;

    return(looking);

} /* end of cuddUniqueConst */

DdNode* cuddUniqueInter	(	DdManager *	unique,
		int	index,
		DdNode *	T,
		DdNode *	E
	)

Function********************************************************************

Synopsis [Checks the unique table for the existence of an internal node.]

Description [Checks the unique table for the existence of an internal node. If it does not exist, it creates a new one. Does not modify the reference count of whatever is returned. A newly created internal node comes back with a reference count 0. For a newly created node, increments the reference counts of what T and E point to. Returns a pointer to the new node if successful; NULL if memory is exhausted or if reordering took place.]

SideEffects [None]

SeeAlso [cuddUniqueInterZdd]

Definition at line 1115 of file cuddTable.c.

{
    int pos;
    unsigned int level;
    int retval;
    DdNodePtr *nodelist;
    DdNode *looking;
    DdNodePtr *previousP;
    DdSubtable *subtable;
    int gcNumber;

#ifdef DD_UNIQUE_PROFILE
    unique->uniqueLookUps++;
#endif

    if (index >= unique->size) {
        if (!ddResizeTable(unique,index)) return(NULL);
    }

    level = unique->perm[index];
    subtable = &(unique->subtables[level]);

#ifdef DD_DEBUG
    assert(level < (unsigned) cuddI(unique,T->index));
    assert(level < (unsigned) cuddI(unique,Cudd_Regular(E)->index));
#endif

    pos = ddHash(T, E, subtable->shift);
    nodelist = subtable->nodelist;
    previousP = &(nodelist[pos]);
    looking = *previousP;

    while (T < cuddT(looking)) {
        previousP = &(looking->next);
        looking = *previousP;
#ifdef DD_UNIQUE_PROFILE
        unique->uniqueLinks++;
#endif
    }
    while (T == cuddT(looking) && E < cuddE(looking)) {
        previousP = &(looking->next);
        looking = *previousP;
#ifdef DD_UNIQUE_PROFILE
        unique->uniqueLinks++;
#endif
    }
    if (T == cuddT(looking) && E == cuddE(looking)) {
        if (looking->ref == 0) {
            cuddReclaim(unique,looking);
        }
        return(looking);
    }

    /* countDead is 0 if deads should be counted and ~0 if they should not. */
    if (unique->autoDyn &&
    unique->keys - (unique->dead & unique->countDead) >= unique->nextDyn) {
#ifdef DD_DEBUG
        retval = Cudd_DebugCheck(unique);
        if (retval != 0) return(NULL);
        retval = Cudd_CheckKeys(unique);
        if (retval != 0) return(NULL);
#endif
        retval = Cudd_ReduceHeap(unique,unique->autoMethod,10); /* 10 = whatever */
        if (retval == 0) unique->reordered = 2;
#ifdef DD_DEBUG
        retval = Cudd_DebugCheck(unique);
        if (retval != 0) unique->reordered = 2;
        retval = Cudd_CheckKeys(unique);
        if (retval != 0) unique->reordered = 2;
#endif
        return(NULL);
    }

    if (subtable->keys > subtable->maxKeys) {
        if (unique->gcEnabled &&
            ((unique->dead > unique->minDead) ||
            ((unique->dead > unique->minDead / 2) &&
            (subtable->dead > subtable->keys * 0.95)))) { /* too many dead */
            (void) cuddGarbageCollect(unique,1);
        } else {
            cuddRehash(unique,(int)level);
        }
        /* Update pointer to insertion point. In the case of rehashing,
        ** the slot may have changed. In the case of garbage collection,
        ** the predecessor may have been dead. */
        pos = ddHash(T, E, subtable->shift);
        nodelist = subtable->nodelist;
        previousP = &(nodelist[pos]);
        looking = *previousP;

        while (T < cuddT(looking)) {
            previousP = &(looking->next);
            looking = *previousP;
#ifdef DD_UNIQUE_PROFILE
            unique->uniqueLinks++;
#endif
        }
        while (T == cuddT(looking) && E < cuddE(looking)) {
            previousP = &(looking->next);
            looking = *previousP;
#ifdef DD_UNIQUE_PROFILE
            unique->uniqueLinks++;
#endif
        }
    }

    gcNumber = unique->garbageCollections;
    looking = cuddAllocNode(unique);
    if (looking == NULL) {
        return(NULL);
    }
    unique->keys++;
    subtable->keys++;

    if (gcNumber != unique->garbageCollections) {
        DdNode *looking2;
        pos = ddHash(T, E, subtable->shift);
        nodelist = subtable->nodelist;
        previousP = &(nodelist[pos]);
        looking2 = *previousP;

        while (T < cuddT(looking2)) {
            previousP = &(looking2->next);
            looking2 = *previousP;
#ifdef DD_UNIQUE_PROFILE
            unique->uniqueLinks++;
#endif
        }
        while (T == cuddT(looking2) && E < cuddE(looking2)) {
            previousP = &(looking2->next);
            looking2 = *previousP;
#ifdef DD_UNIQUE_PROFILE
            unique->uniqueLinks++;
#endif
        }
    }
    looking->index = index;
    cuddT(looking) = T;
    cuddE(looking) = E;
    looking->next = *previousP;
    *previousP = looking;
    cuddSatInc(T->ref);         /* we know T is a regular pointer */
    cuddRef(E);

#ifdef DD_DEBUG
    cuddCheckCollisionOrdering(unique,level,pos);
#endif

    return(looking);

} /* end of cuddUniqueInter */

DdNode* cuddUniqueInterIVO	(	DdManager *	unique,
		int	index,
		DdNode *	T,
		DdNode *	E
	)

Function********************************************************************

Synopsis [Wrapper for cuddUniqueInter that is independent of variable ordering.]

Description [Wrapper for cuddUniqueInter that is independent of variable ordering (IVO). This function does not require parameter index to precede the indices of the top nodes of T and E in the variable order. Returns a pointer to the result node under normal conditions; NULL if reordering occurred or memory was exhausted.]

SideEffects [None]

SeeAlso [cuddUniqueInter Cudd_MakeBddFromZddCover]

Definition at line 1289 of file cuddTable.c.

{
    DdNode *result;
    DdNode *v;

    v = cuddUniqueInter(unique, index, DD_ONE(unique),
                        Cudd_Not(DD_ONE(unique)));
    if (v == NULL)
        return(NULL);
    cuddRef(v);
    result = cuddBddIteRecur(unique, v, T, E);
    Cudd_RecursiveDeref(unique, v);
    return(result);
}

DdNode* cuddUniqueInterZdd	(	DdManager *	unique,
		int	index,
		DdNode *	T,
		DdNode *	E
	)

Function********************************************************************

Synopsis [Checks the unique table for the existence of an internal ZDD node.]

Description [Checks the unique table for the existence of an internal ZDD node. If it does not exist, it creates a new one. Does not modify the reference count of whatever is returned. A newly created internal node comes back with a reference count 0. For a newly created node, increments the reference counts of what T and E point to. Returns a pointer to the new node if successful; NULL if memory is exhausted or if reordering took place.]

SideEffects [None]

SeeAlso [cuddUniqueInter]

Definition at line 1328 of file cuddTable.c.

{
    int pos;
    unsigned int level;
    int retval;
    DdNodePtr *nodelist;
    DdNode *looking;
    DdSubtable *subtable;

#ifdef DD_UNIQUE_PROFILE
    unique->uniqueLookUps++;
#endif

    if (index >= unique->sizeZ) {
        if (!cuddResizeTableZdd(unique,index)) return(NULL);
    }

    level = unique->permZ[index];
    subtable = &(unique->subtableZ[level]);

#ifdef DD_DEBUG
    assert(level < (unsigned) cuddIZ(unique,T->index));
    assert(level < (unsigned) cuddIZ(unique,Cudd_Regular(E)->index));
#endif

    if (subtable->keys > subtable->maxKeys) {
        if (unique->gcEnabled && ((unique->deadZ > unique->minDead) ||
        (10 * subtable->dead > 9 * subtable->keys))) {  /* too many dead */
            (void) cuddGarbageCollect(unique,1);
        } else {
            ddRehashZdd(unique,(int)level);
        }
    }

    pos = ddHash(T, E, subtable->shift);
    nodelist = subtable->nodelist;
    looking = nodelist[pos];

    while (looking != NULL) {
        if (cuddT(looking) == T && cuddE(looking) == E) {
            if (looking->ref == 0) {
                cuddReclaimZdd(unique,looking);
            }
            return(looking);
        }
        looking = looking->next;
#ifdef DD_UNIQUE_PROFILE
        unique->uniqueLinks++;
#endif
    }

    /* countDead is 0 if deads should be counted and ~0 if they should not. */
    if (unique->autoDynZ &&
    unique->keysZ - (unique->deadZ & unique->countDead) >= unique->nextDyn) {
#ifdef DD_DEBUG
        retval = Cudd_DebugCheck(unique);
        if (retval != 0) return(NULL);
        retval = Cudd_CheckKeys(unique);
        if (retval != 0) return(NULL);
#endif
        retval = Cudd_zddReduceHeap(unique,unique->autoMethodZ,10); /* 10 = whatever */
        if (retval == 0) unique->reordered = 2;
#ifdef DD_DEBUG
        retval = Cudd_DebugCheck(unique);
        if (retval != 0) unique->reordered = 2;
        retval = Cudd_CheckKeys(unique);
        if (retval != 0) unique->reordered = 2;
#endif
        return(NULL);
    }

    unique->keysZ++;
    subtable->keys++;

    looking = cuddAllocNode(unique);
    if (looking == NULL) return(NULL);
    looking->index = index;
    cuddT(looking) = T;
    cuddE(looking) = E;
    looking->next = nodelist[pos];
    nodelist[pos] = looking;
    cuddRef(T);
    cuddRef(E);

    return(looking);

} /* end of cuddUniqueInterZdd */

DdNode* cuddZddGetNode	(	DdManager *	zdd,
		int	id,
		DdNode *	T,
		DdNode *	E
	)

Function********************************************************************

Synopsis [Wrapper for cuddUniqueInterZdd.]

Description [Wrapper for cuddUniqueInterZdd, which applies the ZDD reduction rule. Returns a pointer to the result node under normal conditions; NULL if reordering occurred or memory was exhausted.]

SideEffects [None]

SeeAlso [cuddUniqueInterZdd]

Definition at line 1028 of file cuddTable.c.

{
    DdNode      *node;

    if (T == DD_ZERO(zdd))
        return(E);
    node = cuddUniqueInterZdd(zdd, id, T, E);
    return(node);

} /* end of cuddZddGetNode */

DdNode* cuddZddGetNodeIVO	(	DdManager *	dd,
		int	index,
		DdNode *	g,
		DdNode *	h
	)

Function********************************************************************

Synopsis [Wrapper for cuddUniqueInterZdd that is independent of variable ordering.]

Description [Wrapper for cuddUniqueInterZdd that is independent of variable ordering (IVO). This function does not require parameter index to precede the indices of the top nodes of g and h in the variable order. Returns a pointer to the result node under normal conditions; NULL if reordering occurred or memory was exhausted.]

SideEffects [None]

SeeAlso [cuddZddGetNode cuddZddIsop]

Definition at line 1061 of file cuddTable.c.

{
    DdNode      *f, *r, *t;
    DdNode      *zdd_one = DD_ONE(dd);
    DdNode      *zdd_zero = DD_ZERO(dd);

    f = cuddUniqueInterZdd(dd, index, zdd_one, zdd_zero);
    if (f == NULL) {
        return(NULL);
    }
    cuddRef(f);
    t = cuddZddProduct(dd, f, g);
    if (t == NULL) {
        Cudd_RecursiveDerefZdd(dd, f);
        return(NULL);
    }
    cuddRef(t);
    Cudd_RecursiveDerefZdd(dd, f);
    r = cuddZddUnion(dd, t, h);
    if (r == NULL) {
        Cudd_RecursiveDerefZdd(dd, t);
        return(NULL);
    }
    cuddRef(r);
    Cudd_RecursiveDerefZdd(dd, t);

    cuddDeref(r);
    return(r);

} /* end of cuddZddGetNodeIVO */

static DD_INLINE void ddFixLimits

(

DdManager *

unique

)

[static]

Function********************************************************************

Synopsis [Adjusts the values of table limits.]

Description [Adjusts the values of table fields controlling the. sizes of subtables and computed table. If the computed table is too small according to the new values, it is resized.]

SideEffects [Modifies manager fields. May resize computed table.]

SeeAlso []

Definition at line 2790 of file cuddTable.c.

{
    unique->minDead = (unsigned) (unique->gcFrac * (double) unique->slots);
    unique->cacheSlack = (int) ddMin(unique->maxCacheHard,
        DD_MAX_CACHE_TO_SLOTS_RATIO * unique->slots) -
        2 * (int) unique->cacheSlots;
    if (unique->cacheSlots < unique->slots/2 && unique->cacheSlack >= 0)
        cuddCacheResize(unique);
    return;

} /* end of ddFixLimits */

static void ddPatchTree	(	DdManager *	dd,
		MtrNode *	treenode
	)			[static]

Function********************************************************************

Synopsis [Fixes a variable tree after the insertion of new subtables.]

Description [Fixes a variable tree after the insertion of new subtables. After such an insertion, the low fields of the tree below the insertion point are inconsistent.]

SideEffects [None]

SeeAlso []

Definition at line 3065 of file cuddTable.c.

{
    MtrNode *auxnode = treenode;

    while (auxnode != NULL) {
        auxnode->low = dd->perm[auxnode->index];
        if (auxnode->child != NULL) {
            ddPatchTree(dd, auxnode->child);
        }
        auxnode = auxnode->younger;
    }

    return;

} /* end of ddPatchTree */

static void ddRehashZdd	(	DdManager *	unique,
		int	i
	)			[static]

AutomaticStart

Function********************************************************************

Synopsis [Rehashes a ZDD unique subtable.]

Description []

SideEffects [None]

SeeAlso [cuddRehash]

Definition at line 2407 of file cuddTable.c.

{
    unsigned int slots, oldslots;
    int shift, oldshift;
    int j, pos;
    DdNodePtr *nodelist, *oldnodelist;
    DdNode *node, *next;
    extern DD_OOMFP MMoutOfMemory;
    DD_OOMFP saveHandler;

    if (unique->slots > unique->looseUpTo) {
        unique->minDead = (unsigned) (DD_GC_FRAC_LO * (double) unique->slots);
#ifdef DD_VERBOSE
        if (unique->gcFrac == DD_GC_FRAC_HI) {
            (void) fprintf(unique->err,"GC fraction = %.2f\t",
                           DD_GC_FRAC_LO);
            (void) fprintf(unique->err,"minDead = %d\n", unique->minDead);
        }
#endif
        unique->gcFrac = DD_GC_FRAC_LO;
    }

    assert(i != CUDD_MAXINDEX);
    oldslots = unique->subtableZ[i].slots;
    oldshift = unique->subtableZ[i].shift;
    oldnodelist = unique->subtableZ[i].nodelist;

    /* Compute the new size of the subtable. Normally, we just
    ** double.  However, after reordering, a table may be severely
    ** overloaded. Therefore, we iterate. */
    slots = oldslots;
    shift = oldshift;
    do {
        slots <<= 1;
        shift--;
    } while (slots * DD_MAX_SUBTABLE_DENSITY < unique->subtableZ[i].keys);

    saveHandler = MMoutOfMemory;
    MMoutOfMemory = Cudd_OutOfMem;
    nodelist = ALLOC(DdNodePtr, slots);
    MMoutOfMemory = saveHandler;
    if (nodelist == NULL) {
        (void) fprintf(unique->err,
                       "Unable to resize ZDD subtable %d for lack of memory.\n",
                       i);
        (void) cuddGarbageCollect(unique,1);
        for (j = 0; j < unique->sizeZ; j++) {
            unique->subtableZ[j].maxKeys <<= 1;
        }
        return;
    }
    unique->subtableZ[i].nodelist = nodelist;
    unique->subtableZ[i].slots = slots;
    unique->subtableZ[i].shift = shift;
    unique->subtableZ[i].maxKeys = slots * DD_MAX_SUBTABLE_DENSITY;
    for (j = 0; (unsigned) j < slots; j++) {
        nodelist[j] = NULL;
    }
    for (j = 0; (unsigned) j < oldslots; j++) {
        node = oldnodelist[j];
        while (node != NULL) {
            next = node->next;
            pos = ddHash(cuddT(node), cuddE(node), shift);
            node->next = nodelist[pos];
            nodelist[pos] = node;
            node = next;
        }
    }
    FREE(oldnodelist);

#ifdef DD_VERBOSE
    (void) fprintf(unique->err,
                   "rehashing layer %d: keys %d dead %d new size %d\n",
                   i, unique->subtableZ[i].keys,
                   unique->subtableZ[i].dead, slots);
#endif

    /* Update global data. */
    unique->memused += (slots - oldslots) * sizeof(DdNode *);
    unique->slots += (slots - oldslots);
    ddFixLimits(unique);

} /* end of ddRehashZdd */

static void ddReportRefMess	(	DdManager *	unique,
		int	i,
		const char *	caller
	)			[static]

Function********************************************************************

Synopsis [Reports problem in garbage collection.]

Description []

SideEffects [None]

SeeAlso [cuddGarbageCollect cuddGarbageCollectZdd]

Definition at line 3142 of file cuddTable.c.

{
    if (i == CUDD_CONST_INDEX) {
        (void) fprintf(unique->err,
                           "%s: problem in constants\n", caller);
    } else if (i != -1) {
        (void) fprintf(unique->err,
                           "%s: problem in table %d\n", caller, i);
    }
    (void) fprintf(unique->err, "  dead count != deleted\n");
    (void) fprintf(unique->err, "  This problem is often due to a missing \
call to Cudd_Ref\n  or to an extra call to Cudd_RecursiveDeref.\n  \
See the CUDD Programmer's Guide for additional details.");
    abort();

} /* end of ddReportRefMess */

static int ddResizeTable	(	DdManager *	unique,
		int	index
	)			[static]

Function********************************************************************

Synopsis [Increases the number of subtables in a unique table so that it meets or exceeds index.]

Description [Increases the number of subtables in a unique table so that it meets or exceeds index. Returns 1 if successful; 0 otherwise.]

SideEffects [None]

SeeAlso [cuddResizeTableZdd]

Definition at line 2508 of file cuddTable.c.

{
    DdSubtable *newsubtables;
    DdNodePtr *newnodelist;
    DdNodePtr *newvars;
    DdNode *sentinel = &(unique->sentinel);
    int oldsize,newsize;
    int i,j,reorderSave;
    int numSlots = unique->initSlots;
    int *newperm, *newinvperm, *newmap;
    DdNode *one, *zero;

    oldsize = unique->size;
    /* Easy case: there is still room in the current table. */
    if (index < unique->maxSize) {
        for (i = oldsize; i <= index; i++) {
            unique->subtables[i].slots = numSlots;
            unique->subtables[i].shift = sizeof(int) * 8 -
                cuddComputeFloorLog2(numSlots);
            unique->subtables[i].keys = 0;
            unique->subtables[i].maxKeys = numSlots * DD_MAX_SUBTABLE_DENSITY;
            unique->subtables[i].dead = 0;
            unique->subtables[i].bindVar = 0;
            unique->subtables[i].varType = CUDD_VAR_PRIMARY_INPUT;
            unique->subtables[i].pairIndex = 0;
            unique->subtables[i].varHandled = 0;
            unique->subtables[i].varToBeGrouped = CUDD_LAZY_NONE;

            unique->perm[i] = i;
            unique->invperm[i] = i;
            newnodelist = unique->subtables[i].nodelist =
                ALLOC(DdNodePtr, numSlots);
            if (newnodelist == NULL) {
                for (j = oldsize; j < i; j++) {
                    FREE(unique->subtables[j].nodelist);
                }
                unique->errorCode = CUDD_MEMORY_OUT;
                return(0);
            }
            for (j = 0; j < numSlots; j++) {
                newnodelist[j] = sentinel;
            }
        }
        if (unique->map != NULL) {
            for (i = oldsize; i <= index; i++) {
                unique->map[i] = i;
            }
        }
    } else {
        /* The current table is too small: we need to allocate a new,
        ** larger one; move all old subtables, and initialize the new
        ** subtables up to index included.
        */
        newsize = index + DD_DEFAULT_RESIZE;
#ifdef DD_VERBOSE
        (void) fprintf(unique->err,
                       "Increasing the table size from %d to %d\n",
                       unique->maxSize, newsize);
#endif
        newsubtables = ALLOC(DdSubtable,newsize);
        if (newsubtables == NULL) {
            unique->errorCode = CUDD_MEMORY_OUT;
            return(0);
        }
        newvars = ALLOC(DdNodePtr,newsize);
        if (newvars == NULL) {
            FREE(newsubtables);
            unique->errorCode = CUDD_MEMORY_OUT;
            return(0);
        }
        newperm = ALLOC(int,newsize);
        if (newperm == NULL) {
            FREE(newsubtables);
            FREE(newvars);
            unique->errorCode = CUDD_MEMORY_OUT;
            return(0);
        }
        newinvperm = ALLOC(int,newsize);
        if (newinvperm == NULL) {
            FREE(newsubtables);
            FREE(newvars);
            FREE(newperm);
            unique->errorCode = CUDD_MEMORY_OUT;
            return(0);
        }
        if (unique->map != NULL) {
            newmap = ALLOC(int,newsize);
            if (newmap == NULL) {
                FREE(newsubtables);
                FREE(newvars);
                FREE(newperm);
                FREE(newinvperm);
                unique->errorCode = CUDD_MEMORY_OUT;
                return(0);
            }
            unique->memused += (newsize - unique->maxSize) * sizeof(int);
        }
        unique->memused += (newsize - unique->maxSize) * ((numSlots+1) *
            sizeof(DdNode *) + 2 * sizeof(int) + sizeof(DdSubtable));
        if (newsize > unique->maxSizeZ) {
            FREE(unique->stack);
            unique->stack = ALLOC(DdNodePtr,newsize + 1);
            if (unique->stack == NULL) {
                FREE(newsubtables);
                FREE(newvars);
                FREE(newperm);
                FREE(newinvperm);
                if (unique->map != NULL) {
                    FREE(newmap);
                }
                unique->errorCode = CUDD_MEMORY_OUT;
                return(0);
            }
            unique->stack[0] = NULL; /* to suppress harmless UMR */
            unique->memused +=
                (newsize - ddMax(unique->maxSize,unique->maxSizeZ))
                * sizeof(DdNode *);
        }
        for (i = 0; i < oldsize; i++) {
            newsubtables[i].slots = unique->subtables[i].slots;
            newsubtables[i].shift = unique->subtables[i].shift;
            newsubtables[i].keys = unique->subtables[i].keys;
            newsubtables[i].maxKeys = unique->subtables[i].maxKeys;
            newsubtables[i].dead = unique->subtables[i].dead;
            newsubtables[i].nodelist = unique->subtables[i].nodelist;
            newsubtables[i].bindVar = unique->subtables[i].bindVar;
            newsubtables[i].varType = unique->subtables[i].varType;
            newsubtables[i].pairIndex = unique->subtables[i].pairIndex;
            newsubtables[i].varHandled = unique->subtables[i].varHandled;
            newsubtables[i].varToBeGrouped = unique->subtables[i].varToBeGrouped;

            newvars[i] = unique->vars[i];
            newperm[i] = unique->perm[i];
            newinvperm[i] = unique->invperm[i];
        }
        for (i = oldsize; i <= index; i++) {
            newsubtables[i].slots = numSlots;
            newsubtables[i].shift = sizeof(int) * 8 -
                cuddComputeFloorLog2(numSlots);
            newsubtables[i].keys = 0;
            newsubtables[i].maxKeys = numSlots * DD_MAX_SUBTABLE_DENSITY;
            newsubtables[i].dead = 0;
            newsubtables[i].bindVar = 0;
            newsubtables[i].varType = CUDD_VAR_PRIMARY_INPUT;
            newsubtables[i].pairIndex = 0;
            newsubtables[i].varHandled = 0;
            newsubtables[i].varToBeGrouped = CUDD_LAZY_NONE;

            newperm[i] = i;
            newinvperm[i] = i;
            newnodelist = newsubtables[i].nodelist = ALLOC(DdNodePtr, numSlots);
            if (newnodelist == NULL) {
                unique->errorCode = CUDD_MEMORY_OUT;
                return(0);
            }
            for (j = 0; j < numSlots; j++) {
                newnodelist[j] = sentinel;
            }
        }
        if (unique->map != NULL) {
            for (i = 0; i < oldsize; i++) {
                newmap[i] = unique->map[i];
            }
            for (i = oldsize; i <= index; i++) {
                newmap[i] = i;
            }
            FREE(unique->map);
            unique->map = newmap;
        }
        FREE(unique->subtables);
        unique->subtables = newsubtables;
        unique->maxSize = newsize;
        FREE(unique->vars);
        unique->vars = newvars;
        FREE(unique->perm);
        unique->perm = newperm;
        FREE(unique->invperm);
        unique->invperm = newinvperm;
    }

    /* Now that the table is in a coherent state, create the new
    ** projection functions. We need to temporarily disable reordering,
    ** because we cannot reorder without projection functions in place.
    **/
    one = unique->one;
    zero = Cudd_Not(one);

    unique->size = index + 1;
    unique->slots += (index + 1 - oldsize) * numSlots;
    ddFixLimits(unique);

    reorderSave = unique->autoDyn;
    unique->autoDyn = 0;
    for (i = oldsize; i <= index; i++) {
        unique->vars[i] = cuddUniqueInter(unique,i,one,zero);
        if (unique->vars[i] == NULL) {
            unique->autoDyn = reorderSave;
            for (j = oldsize; j < i; j++) {
                Cudd_IterDerefBdd(unique,unique->vars[j]);
                cuddDeallocNode(unique,unique->vars[j]);
                unique->vars[j] = NULL;
            }
            for (j = oldsize; j <= index; j++) {
                FREE(unique->subtables[j].nodelist);
                unique->subtables[j].nodelist = NULL;
            }
            unique->size = oldsize;
            unique->slots -= (index + 1 - oldsize) * numSlots;
            ddFixLimits(unique);
            return(0);
        }
        cuddRef(unique->vars[i]);
    }
    unique->autoDyn = reorderSave;

    return(1);

} /* end of ddResizeTable */

---

Variable Documentation

char rcsid [] DD_UNUSED = "$Id: cuddTable.c,v 1.122 2009/02/19 16:24:28 fabio Exp $" [static]

Definition at line 120 of file cuddTable.c.