diff options
Diffstat (limited to 'abc70930/src/bdd/cudd/cuddZddSymm.c')
| -rw-r--r-- | abc70930/src/bdd/cudd/cuddZddSymm.c | 1677 |
1 files changed, 1677 insertions, 0 deletions
diff --git a/abc70930/src/bdd/cudd/cuddZddSymm.c b/abc70930/src/bdd/cudd/cuddZddSymm.c new file mode 100644 index 00000000..54019892 --- /dev/null +++ b/abc70930/src/bdd/cudd/cuddZddSymm.c @@ -0,0 +1,1677 @@ +/**CFile*********************************************************************** + + FileName [cuddZddSymm.c] + + PackageName [cudd] + + Synopsis [Functions for symmetry-based ZDD variable reordering.] + + Description [External procedures included in this module: + <ul> + <li> Cudd_zddSymmProfile() + </ul> + Internal procedures included in this module: + <ul> + <li> cuddZddSymmCheck() + <li> cuddZddSymmSifting() + <li> cuddZddSymmSiftingConv() + </ul> + Static procedures included in this module: + <ul> + <li> cuddZddUniqueCompare() + <li> cuddZddSymmSiftingAux() + <li> cuddZddSymmSiftingConvAux() + <li> cuddZddSymmSifting_up() + <li> cuddZddSymmSifting_down() + <li> zdd_group_move() + <li> cuddZddSymmSiftingBackward() + <li> zdd_group_move_backward() + </ul> + ] + + SeeAlso [cuddSymmetry.c] + + Author [Hyong-Kyoon Shin, In-Ho Moon] + + Copyright [ This file was created at the University of Colorado at + Boulder. The University of Colorado at Boulder makes no warranty + about the suitability of this software for any purpose. It is + presented on an AS IS basis.] + +******************************************************************************/ + +#include "util_hack.h" +#include "cuddInt.h" + +/*---------------------------------------------------------------------------*/ +/* Constant declarations */ +/*---------------------------------------------------------------------------*/ + +#define ZDD_MV_OOM (Move *)1 + +/*---------------------------------------------------------------------------*/ +/* Stucture declarations */ +/*---------------------------------------------------------------------------*/ + +/*---------------------------------------------------------------------------*/ +/* Type declarations */ +/*---------------------------------------------------------------------------*/ + +/*---------------------------------------------------------------------------*/ +/* Variable declarations */ +/*---------------------------------------------------------------------------*/ + +#ifndef lint +static char rcsid[] DD_UNUSED = "$Id: cuddZddSymm.c,v 1.1.1.1 2003/02/24 22:23:54 wjiang Exp $"; +#endif + +extern int *zdd_entry; + +extern int zddTotalNumberSwapping; + +static DdNode *empty; + +/*---------------------------------------------------------------------------*/ +/* Macro declarations */ +/*---------------------------------------------------------------------------*/ + + +/**AutomaticStart*************************************************************/ + +/*---------------------------------------------------------------------------*/ +/* Static function prototypes */ +/*---------------------------------------------------------------------------*/ + +static int cuddZddSymmSiftingAux ARGS((DdManager *table, int x, int x_low, int x_high)); +static int cuddZddSymmSiftingConvAux ARGS((DdManager *table, int x, int x_low, int x_high)); +static Move * cuddZddSymmSifting_up ARGS((DdManager *table, int x, int x_low, int initial_size)); +static Move * cuddZddSymmSifting_down ARGS((DdManager *table, int x, int x_high, int initial_size)); +static int cuddZddSymmSiftingBackward ARGS((DdManager *table, Move *moves, int size)); +static int zdd_group_move ARGS((DdManager *table, int x, int y, Move **moves)); +static int zdd_group_move_backward ARGS((DdManager *table, int x, int y)); +static void cuddZddSymmSummary ARGS((DdManager *table, int lower, int upper, int *symvars, int *symgroups)); + +/**AutomaticEnd***************************************************************/ + + +/*---------------------------------------------------------------------------*/ +/* Definition of exported functions */ +/*---------------------------------------------------------------------------*/ + + +/**Function******************************************************************** + + Synopsis [Prints statistics on symmetric ZDD variables.] + + Description [] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +void +Cudd_zddSymmProfile( + DdManager * table, + int lower, + int upper) +{ + int i, x, gbot; + int TotalSymm = 0; + int TotalSymmGroups = 0; + int nvars; + + nvars = table->sizeZ; + + for (i = lower; i < upper; i++) { + if (table->subtableZ[i].next != (unsigned) i) { + x = i; + (void) fprintf(table->out,"Group:"); + do { + (void) fprintf(table->out," %d", table->invpermZ[x]); + TotalSymm++; + gbot = x; + x = table->subtableZ[x].next; + } while (x != i); + TotalSymmGroups++; +#ifdef DD_DEBUG + assert(table->subtableZ[gbot].next == (unsigned) i); +#endif + i = gbot; + (void) fprintf(table->out,"\n"); + } + } + (void) fprintf(table->out,"Total Symmetric = %d\n", TotalSymm); + (void) fprintf(table->out,"Total Groups = %d\n", TotalSymmGroups); + +} /* end of Cudd_zddSymmProfile */ + + +/*---------------------------------------------------------------------------*/ +/* Definition of internal functions */ +/*---------------------------------------------------------------------------*/ + + +/**Function******************************************************************** + + Synopsis [Checks for symmetry of x and y.] + + Description [Checks for symmetry of x and y. Ignores projection + functions, unless they are isolated. Returns 1 in case of + symmetry; 0 otherwise.] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +int +cuddZddSymmCheck( + DdManager * table, + int x, + int y) +{ + int i; + DdNode *f, *f0, *f1, *f01, *f00, *f11, *f10; + int yindex; + int xsymmy = 1; + int xsymmyp = 1; + int arccount = 0; + int TotalRefCount = 0; + int symm_found; + + empty = table->zero; + + yindex = table->invpermZ[y]; + for (i = table->subtableZ[x].slots - 1; i >= 0; i--) { + f = table->subtableZ[x].nodelist[i]; + while (f != NULL) { + /* Find f1, f0, f11, f10, f01, f00 */ + f1 = cuddT(f); + f0 = cuddE(f); + if ((int) f1->index == yindex) { + f11 = cuddT(f1); + f10 = cuddE(f1); + if (f10 != empty) + arccount++; + } else { + if ((int) f0->index != yindex) { + return(0); /* f bypasses layer y */ + } + f11 = empty; + f10 = f1; + } + if ((int) f0->index == yindex) { + f01 = cuddT(f0); + f00 = cuddE(f0); + if (f00 != empty) + arccount++; + } else { + f01 = empty; + f00 = f0; + } + if (f01 != f10) + xsymmy = 0; + if (f11 != f00) + xsymmyp = 0; + if ((xsymmy == 0) && (xsymmyp == 0)) + return(0); + + f = f->next; + } /* for each element of the collision list */ + } /* for each slot of the subtable */ + + /* Calculate the total reference counts of y + ** whose else arc is not empty. + */ + for (i = table->subtableZ[y].slots - 1; i >= 0; i--) { + f = table->subtableZ[y].nodelist[i]; + while (f != NIL(DdNode)) { + if (cuddE(f) != empty) + TotalRefCount += f->ref; + f = f->next; + } + } + + symm_found = (arccount == TotalRefCount); +#if defined(DD_DEBUG) && defined(DD_VERBOSE) + if (symm_found) { + int xindex = table->invpermZ[x]; + (void) fprintf(table->out, + "Found symmetry! x =%d\ty = %d\tPos(%d,%d)\n", + xindex,yindex,x,y); + } +#endif + + return(symm_found); + +} /* end cuddZddSymmCheck */ + + +/**Function******************************************************************** + + Synopsis [Symmetric sifting algorithm for ZDDs.] + + Description [Symmetric sifting algorithm. + Assumes that no dead nodes are present. + <ol> + <li> Order all the variables according to the number of entries in + each unique subtable. + <li> Sift the variable up and down, remembering each time the total + size of the ZDD heap and grouping variables that are symmetric. + <li> Select the best permutation. + <li> Repeat 3 and 4 for all variables. + </ol> + Returns 1 plus the number of symmetric variables if successful; 0 + otherwise.] + + SideEffects [None] + + SeeAlso [cuddZddSymmSiftingConv] + +******************************************************************************/ +int +cuddZddSymmSifting( + DdManager * table, + int lower, + int upper) +{ + int i; + int *var; + int nvars; + int x; + int result; + int symvars; + int symgroups; + int iteration; +#ifdef DD_STATS + int previousSize; +#endif + + nvars = table->sizeZ; + + /* Find order in which to sift variables. */ + var = NULL; + zdd_entry = ALLOC(int, nvars); + if (zdd_entry == NULL) { + table->errorCode = CUDD_MEMORY_OUT; + goto cuddZddSymmSiftingOutOfMem; + } + var = ALLOC(int, nvars); + if (var == NULL) { + table->errorCode = CUDD_MEMORY_OUT; + goto cuddZddSymmSiftingOutOfMem; + } + + for (i = 0; i < nvars; i++) { + x = table->permZ[i]; + zdd_entry[i] = table->subtableZ[x].keys; + var[i] = i; + } + + qsort((void *)var, nvars, sizeof(int), (int (*)(const void *, const void *))cuddZddUniqueCompare); + + /* Initialize the symmetry of each subtable to itself. */ + for (i = lower; i <= upper; i++) + table->subtableZ[i].next = i; + + iteration = ddMin(table->siftMaxVar, nvars); + for (i = 0; i < iteration; i++) { + if (zddTotalNumberSwapping >= table->siftMaxSwap) + break; + x = table->permZ[var[i]]; +#ifdef DD_STATS + previousSize = table->keysZ; +#endif + if (x < lower || x > upper) continue; + if (table->subtableZ[x].next == (unsigned) x) { + result = cuddZddSymmSiftingAux(table, x, lower, upper); + if (!result) + goto cuddZddSymmSiftingOutOfMem; +#ifdef DD_STATS + if (table->keysZ < (unsigned) previousSize) { + (void) fprintf(table->out,"-"); + } else if (table->keysZ > (unsigned) previousSize) { + (void) fprintf(table->out,"+"); +#ifdef DD_VERBOSE + (void) fprintf(table->out,"\nSize increased from %d to %d while sifting variable %d\n", previousSize, table->keysZ, var[i]); +#endif + } else { + (void) fprintf(table->out,"="); + } + fflush(table->out); +#endif + } + } + + FREE(var); + FREE(zdd_entry); + + cuddZddSymmSummary(table, lower, upper, &symvars, &symgroups); + +#ifdef DD_STATS + (void) fprintf(table->out,"\n#:S_SIFTING %8d: symmetric variables\n",symvars); + (void) fprintf(table->out,"#:G_SIFTING %8d: symmetric groups\n",symgroups); +#endif + + return(1+symvars); + +cuddZddSymmSiftingOutOfMem: + + if (zdd_entry != NULL) + FREE(zdd_entry); + if (var != NULL) + FREE(var); + + return(0); + +} /* end of cuddZddSymmSifting */ + + +/**Function******************************************************************** + + Synopsis [Symmetric sifting to convergence algorithm for ZDDs.] + + Description [Symmetric sifting to convergence algorithm for ZDDs. + Assumes that no dead nodes are present. + <ol> + <li> Order all the variables according to the number of entries in + each unique subtable. + <li> Sift the variable up and down, remembering each time the total + size of the ZDD heap and grouping variables that are symmetric. + <li> Select the best permutation. + <li> Repeat 3 and 4 for all variables. + <li> Repeat 1-4 until no further improvement. + </ol> + Returns 1 plus the number of symmetric variables if successful; 0 + otherwise.] + + SideEffects [None] + + SeeAlso [cuddZddSymmSifting] + +******************************************************************************/ +int +cuddZddSymmSiftingConv( + DdManager * table, + int lower, + int upper) +{ + int i; + int *var; + int nvars; + int initialSize; + int x; + int result; + int symvars; + int symgroups; + int classes; + int iteration; +#ifdef DD_STATS + int previousSize; +#endif + + initialSize = table->keysZ; + + nvars = table->sizeZ; + + /* Find order in which to sift variables. */ + var = NULL; + zdd_entry = ALLOC(int, nvars); + if (zdd_entry == NULL) { + table->errorCode = CUDD_MEMORY_OUT; + goto cuddZddSymmSiftingConvOutOfMem; + } + var = ALLOC(int, nvars); + if (var == NULL) { + table->errorCode = CUDD_MEMORY_OUT; + goto cuddZddSymmSiftingConvOutOfMem; + } + + for (i = 0; i < nvars; i++) { + x = table->permZ[i]; + zdd_entry[i] = table->subtableZ[x].keys; + var[i] = i; + } + + qsort((void *)var, nvars, sizeof(int), (int (*)(const void *, const void *))cuddZddUniqueCompare); + + /* Initialize the symmetry of each subtable to itself + ** for first pass of converging symmetric sifting. + */ + for (i = lower; i <= upper; i++) + table->subtableZ[i].next = i; + + iteration = ddMin(table->siftMaxVar, table->sizeZ); + for (i = 0; i < iteration; i++) { + if (zddTotalNumberSwapping >= table->siftMaxSwap) + break; + x = table->permZ[var[i]]; + if (x < lower || x > upper) continue; + /* Only sift if not in symmetry group already. */ + if (table->subtableZ[x].next == (unsigned) x) { +#ifdef DD_STATS + previousSize = table->keysZ; +#endif + result = cuddZddSymmSiftingAux(table, x, lower, upper); + if (!result) + goto cuddZddSymmSiftingConvOutOfMem; +#ifdef DD_STATS + if (table->keysZ < (unsigned) previousSize) { + (void) fprintf(table->out,"-"); + } else if (table->keysZ > (unsigned) previousSize) { + (void) fprintf(table->out,"+"); +#ifdef DD_VERBOSE + (void) fprintf(table->out,"\nSize increased from %d to %d while sifting variable %d\n", previousSize, table->keysZ, var[i]); +#endif + } else { + (void) fprintf(table->out,"="); + } + fflush(table->out); +#endif + } + } + + /* Sifting now until convergence. */ + while ((unsigned) initialSize > table->keysZ) { + initialSize = table->keysZ; +#ifdef DD_STATS + (void) fprintf(table->out,"\n"); +#endif + /* Here we consider only one representative for each symmetry class. */ + for (x = lower, classes = 0; x <= upper; x++, classes++) { + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + /* Here x is the largest index in a group. + ** Groups consists of adjacent variables. + ** Hence, the next increment of x will move it to a new group. + */ + i = table->invpermZ[x]; + zdd_entry[i] = table->subtableZ[x].keys; + var[classes] = i; + } + + qsort((void *)var,classes,sizeof(int),(int (*)(const void *, const void *))cuddZddUniqueCompare); + + /* Now sift. */ + iteration = ddMin(table->siftMaxVar, nvars); + for (i = 0; i < iteration; i++) { + if (zddTotalNumberSwapping >= table->siftMaxSwap) + break; + x = table->permZ[var[i]]; + if ((unsigned) x >= table->subtableZ[x].next) { +#ifdef DD_STATS + previousSize = table->keysZ; +#endif + result = cuddZddSymmSiftingConvAux(table, x, lower, upper); + if (!result) + goto cuddZddSymmSiftingConvOutOfMem; +#ifdef DD_STATS + if (table->keysZ < (unsigned) previousSize) { + (void) fprintf(table->out,"-"); + } else if (table->keysZ > (unsigned) previousSize) { + (void) fprintf(table->out,"+"); +#ifdef DD_VERBOSE + (void) fprintf(table->out,"\nSize increased from %d to %d while sifting variable %d\n", previousSize, table->keysZ, var[i]); +#endif + } else { + (void) fprintf(table->out,"="); + } + fflush(table->out); +#endif + } + } /* for */ + } + + cuddZddSymmSummary(table, lower, upper, &symvars, &symgroups); + +#ifdef DD_STATS + (void) fprintf(table->out,"\n#:S_SIFTING %8d: symmetric variables\n", + symvars); + (void) fprintf(table->out,"#:G_SIFTING %8d: symmetric groups\n", + symgroups); +#endif + + FREE(var); + FREE(zdd_entry); + + return(1+symvars); + +cuddZddSymmSiftingConvOutOfMem: + + if (zdd_entry != NULL) + FREE(zdd_entry); + if (var != NULL) + FREE(var); + + return(0); + +} /* end of cuddZddSymmSiftingConv */ + + +/*---------------------------------------------------------------------------*/ +/* Definition of static functions */ +/*---------------------------------------------------------------------------*/ + + +/**Function******************************************************************** + + Synopsis [Given x_low <= x <= x_high moves x up and down between the + boundaries.] + + Description [Given x_low <= x <= x_high moves x up and down between the + boundaries. Finds the best position and does the required changes. + Assumes that x is not part of a symmetry group. Returns 1 if + successful; 0 otherwise.] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +static int +cuddZddSymmSiftingAux( + DdManager * table, + int x, + int x_low, + int x_high) +{ + Move *move; + Move *move_up; /* list of up move */ + Move *move_down; /* list of down move */ + int initial_size; + int result; + int i; + int topbot; /* index to either top or bottom of symmetry group */ + int init_group_size, final_group_size; + + initial_size = table->keysZ; + + move_down = NULL; + move_up = NULL; + + /* Look for consecutive symmetries above x. */ + for (i = x; i > x_low; i--) { + if (!cuddZddSymmCheck(table, i - 1, i)) + break; + /* find top of i-1's symmetry */ + topbot = table->subtableZ[i - 1].next; + table->subtableZ[i - 1].next = i; + table->subtableZ[x].next = topbot; + /* x is bottom of group so its symmetry is top of i-1's + group */ + i = topbot + 1; /* add 1 for i--, new i is top of symm group */ + } + /* Look for consecutive symmetries below x. */ + for (i = x; i < x_high; i++) { + if (!cuddZddSymmCheck(table, i, i + 1)) + break; + /* find bottom of i+1's symm group */ + topbot = i + 1; + while ((unsigned) topbot < table->subtableZ[topbot].next) + topbot = table->subtableZ[topbot].next; + + table->subtableZ[topbot].next = table->subtableZ[i].next; + table->subtableZ[i].next = i + 1; + i = topbot - 1; /* add 1 for i++, + new i is bottom of symm group */ + } + + /* Now x maybe in the middle of a symmetry group. */ + if (x == x_low) { /* Sift down */ + /* Find bottom of x's symm group */ + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + + i = table->subtableZ[x].next; + init_group_size = x - i + 1; + + move_down = cuddZddSymmSifting_down(table, x, x_high, + initial_size); + /* after that point x --> x_high, unless early term */ + if (move_down == ZDD_MV_OOM) + goto cuddZddSymmSiftingAuxOutOfMem; + + if (move_down == NULL || + table->subtableZ[move_down->y].next != move_down->y) { + /* symmetry detected may have to make another complete + pass */ + if (move_down != NULL) + x = move_down->y; + else + x = table->subtableZ[x].next; + i = x; + while ((unsigned) i < table->subtableZ[i].next) { + i = table->subtableZ[i].next; + } + final_group_size = i - x + 1; + + if (init_group_size == final_group_size) { + /* No new symmetry groups detected, + return to best position */ + result = cuddZddSymmSiftingBackward(table, + move_down, initial_size); + } + else { + initial_size = table->keysZ; + move_up = cuddZddSymmSifting_up(table, x, x_low, + initial_size); + result = cuddZddSymmSiftingBackward(table, move_up, + initial_size); + } + } + else { + result = cuddZddSymmSiftingBackward(table, move_down, + initial_size); + /* move backward and stop at best position */ + } + if (!result) + goto cuddZddSymmSiftingAuxOutOfMem; + } + else if (x == x_high) { /* Sift up */ + /* Find top of x's symm group */ + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + x = table->subtableZ[x].next; + + i = x; + while ((unsigned) i < table->subtableZ[i].next) { + i = table->subtableZ[i].next; + } + init_group_size = i - x + 1; + + move_up = cuddZddSymmSifting_up(table, x, x_low, initial_size); + /* after that point x --> x_low, unless early term */ + if (move_up == ZDD_MV_OOM) + goto cuddZddSymmSiftingAuxOutOfMem; + + if (move_up == NULL || + table->subtableZ[move_up->x].next != move_up->x) { + /* symmetry detected may have to make another complete + pass */ + if (move_up != NULL) + x = move_up->x; + else { + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + } + i = table->subtableZ[x].next; + final_group_size = x - i + 1; + + if (init_group_size == final_group_size) { + /* No new symmetry groups detected, + return to best position */ + result = cuddZddSymmSiftingBackward(table, move_up, + initial_size); + } + else { + initial_size = table->keysZ; + move_down = cuddZddSymmSifting_down(table, x, x_high, + initial_size); + result = cuddZddSymmSiftingBackward(table, move_down, + initial_size); + } + } + else { + result = cuddZddSymmSiftingBackward(table, move_up, + initial_size); + /* move backward and stop at best position */ + } + if (!result) + goto cuddZddSymmSiftingAuxOutOfMem; + } + else if ((x - x_low) > (x_high - x)) { /* must go down first: + shorter */ + /* Find bottom of x's symm group */ + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + + move_down = cuddZddSymmSifting_down(table, x, x_high, + initial_size); + /* after that point x --> x_high, unless early term */ + if (move_down == ZDD_MV_OOM) + goto cuddZddSymmSiftingAuxOutOfMem; + + if (move_down != NULL) { + x = move_down->y; + } + else { + x = table->subtableZ[x].next; + } + i = x; + while ((unsigned) i < table->subtableZ[i].next) { + i = table->subtableZ[i].next; + } + init_group_size = i - x + 1; + + move_up = cuddZddSymmSifting_up(table, x, x_low, initial_size); + if (move_up == ZDD_MV_OOM) + goto cuddZddSymmSiftingAuxOutOfMem; + + if (move_up == NULL || + table->subtableZ[move_up->x].next != move_up->x) { + /* symmetry detected may have to make another complete + pass */ + if (move_up != NULL) { + x = move_up->x; + } + else { + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + } + i = table->subtableZ[x].next; + final_group_size = x - i + 1; + + if (init_group_size == final_group_size) { + /* No new symmetry groups detected, + return to best position */ + result = cuddZddSymmSiftingBackward(table, move_up, + initial_size); + } + else { + while (move_down != NULL) { + move = move_down->next; + cuddDeallocNode(table, (DdNode *)move_down); + move_down = move; + } + initial_size = table->keysZ; + move_down = cuddZddSymmSifting_down(table, x, x_high, + initial_size); + result = cuddZddSymmSiftingBackward(table, move_down, + initial_size); + } + } + else { + result = cuddZddSymmSiftingBackward(table, move_up, + initial_size); + /* move backward and stop at best position */ + } + if (!result) + goto cuddZddSymmSiftingAuxOutOfMem; + } + else { /* moving up first:shorter */ + /* Find top of x's symmetry group */ + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + x = table->subtableZ[x].next; + + move_up = cuddZddSymmSifting_up(table, x, x_low, initial_size); + /* after that point x --> x_high, unless early term */ + if (move_up == ZDD_MV_OOM) + goto cuddZddSymmSiftingAuxOutOfMem; + + if (move_up != NULL) { + x = move_up->x; + } + else { + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + } + i = table->subtableZ[x].next; + init_group_size = x - i + 1; + + move_down = cuddZddSymmSifting_down(table, x, x_high, + initial_size); + if (move_down == ZDD_MV_OOM) + goto cuddZddSymmSiftingAuxOutOfMem; + + if (move_down == NULL || + table->subtableZ[move_down->y].next != move_down->y) { + /* symmetry detected may have to make another complete + pass */ + if (move_down != NULL) { + x = move_down->y; + } + else { + x = table->subtableZ[x].next; + } + i = x; + while ((unsigned) i < table->subtableZ[i].next) { + i = table->subtableZ[i].next; + } + final_group_size = i - x + 1; + + if (init_group_size == final_group_size) { + /* No new symmetries detected, + go back to best position */ + result = cuddZddSymmSiftingBackward(table, move_down, + initial_size); + } + else { + while (move_up != NULL) { + move = move_up->next; + cuddDeallocNode(table, (DdNode *)move_up); + move_up = move; + } + initial_size = table->keysZ; + move_up = cuddZddSymmSifting_up(table, x, x_low, + initial_size); + result = cuddZddSymmSiftingBackward(table, move_up, + initial_size); + } + } + else { + result = cuddZddSymmSiftingBackward(table, move_down, + initial_size); + /* move backward and stop at best position */ + } + if (!result) + goto cuddZddSymmSiftingAuxOutOfMem; + } + + while (move_down != NULL) { + move = move_down->next; + cuddDeallocNode(table, (DdNode *)move_down); + move_down = move; + } + while (move_up != NULL) { + move = move_up->next; + cuddDeallocNode(table, (DdNode *)move_up); + move_up = move; + } + + return(1); + +cuddZddSymmSiftingAuxOutOfMem: + if (move_down != ZDD_MV_OOM) { + while (move_down != NULL) { + move = move_down->next; + cuddDeallocNode(table, (DdNode *)move_down); + move_down = move; + } + } + if (move_up != ZDD_MV_OOM) { + while (move_up != NULL) { + move = move_up->next; + cuddDeallocNode(table, (DdNode *)move_up); + move_up = move; + } + } + + return(0); + +} /* end of cuddZddSymmSiftingAux */ + + +/**Function******************************************************************** + + Synopsis [Given x_low <= x <= x_high moves x up and down between the + boundaries.] + + Description [Given x_low <= x <= x_high moves x up and down between the + boundaries. Finds the best position and does the required changes. + Assumes that x is either an isolated variable, or it is the bottom of + a symmetry group. All symmetries may not have been found, because of + exceeded growth limit. Returns 1 if successful; 0 otherwise.] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +static int +cuddZddSymmSiftingConvAux( + DdManager * table, + int x, + int x_low, + int x_high) +{ + Move *move; + Move *move_up; /* list of up move */ + Move *move_down; /* list of down move */ + int initial_size; + int result; + int i; + int init_group_size, final_group_size; + + initial_size = table->keysZ; + + move_down = NULL; + move_up = NULL; + + if (x == x_low) { /* Sift down */ + i = table->subtableZ[x].next; + init_group_size = x - i + 1; + + move_down = cuddZddSymmSifting_down(table, x, x_high, + initial_size); + /* after that point x --> x_high, unless early term */ + if (move_down == ZDD_MV_OOM) + goto cuddZddSymmSiftingConvAuxOutOfMem; + + if (move_down == NULL || + table->subtableZ[move_down->y].next != move_down->y) { + /* symmetry detected may have to make another complete + pass */ + if (move_down != NULL) + x = move_down->y; + else { + while ((unsigned) x < table->subtableZ[x].next); + x = table->subtableZ[x].next; + x = table->subtableZ[x].next; + } + i = x; + while ((unsigned) i < table->subtableZ[i].next) { + i = table->subtableZ[i].next; + } + final_group_size = i - x + 1; + + if (init_group_size == final_group_size) { + /* No new symmetries detected, + go back to best position */ + result = cuddZddSymmSiftingBackward(table, move_down, + initial_size); + } + else { + initial_size = table->keysZ; + move_up = cuddZddSymmSifting_up(table, x, x_low, + initial_size); + result = cuddZddSymmSiftingBackward(table, move_up, + initial_size); + } + } + else { + result = cuddZddSymmSiftingBackward(table, move_down, + initial_size); + /* move backward and stop at best position */ + } + if (!result) + goto cuddZddSymmSiftingConvAuxOutOfMem; + } + else if (x == x_high) { /* Sift up */ + /* Find top of x's symm group */ + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + x = table->subtableZ[x].next; + + i = x; + while ((unsigned) i < table->subtableZ[i].next) { + i = table->subtableZ[i].next; + } + init_group_size = i - x + 1; + + move_up = cuddZddSymmSifting_up(table, x, x_low, initial_size); + /* after that point x --> x_low, unless early term */ + if (move_up == ZDD_MV_OOM) + goto cuddZddSymmSiftingConvAuxOutOfMem; + + if (move_up == NULL || + table->subtableZ[move_up->x].next != move_up->x) { + /* symmetry detected may have to make another complete + pass */ + if (move_up != NULL) + x = move_up->x; + else { + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + } + i = table->subtableZ[x].next; + final_group_size = x - i + 1; + + if (init_group_size == final_group_size) { + /* No new symmetry groups detected, + return to best position */ + result = cuddZddSymmSiftingBackward(table, move_up, + initial_size); + } + else { + initial_size = table->keysZ; + move_down = cuddZddSymmSifting_down(table, x, x_high, + initial_size); + result = cuddZddSymmSiftingBackward(table, move_down, + initial_size); + } + } + else { + result = cuddZddSymmSiftingBackward(table, move_up, + initial_size); + /* move backward and stop at best position */ + } + if (!result) + goto cuddZddSymmSiftingConvAuxOutOfMem; + } + else if ((x - x_low) > (x_high - x)) { /* must go down first: + shorter */ + move_down = cuddZddSymmSifting_down(table, x, x_high, + initial_size); + /* after that point x --> x_high */ + if (move_down == ZDD_MV_OOM) + goto cuddZddSymmSiftingConvAuxOutOfMem; + + if (move_down != NULL) { + x = move_down->y; + } + else { + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + x = table->subtableZ[x].next; + } + i = x; + while ((unsigned) i < table->subtableZ[i].next) { + i = table->subtableZ[i].next; + } + init_group_size = i - x + 1; + + move_up = cuddZddSymmSifting_up(table, x, x_low, initial_size); + if (move_up == ZDD_MV_OOM) + goto cuddZddSymmSiftingConvAuxOutOfMem; + + if (move_up == NULL || + table->subtableZ[move_up->x].next != move_up->x) { + /* symmetry detected may have to make another complete + pass */ + if (move_up != NULL) { + x = move_up->x; + } + else { + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + } + i = table->subtableZ[x].next; + final_group_size = x - i + 1; + + if (init_group_size == final_group_size) { + /* No new symmetry groups detected, + return to best position */ + result = cuddZddSymmSiftingBackward(table, move_up, + initial_size); + } + else { + while (move_down != NULL) { + move = move_down->next; + cuddDeallocNode(table, (DdNode *)move_down); + move_down = move; + } + initial_size = table->keysZ; + move_down = cuddZddSymmSifting_down(table, x, x_high, + initial_size); + result = cuddZddSymmSiftingBackward(table, move_down, + initial_size); + } + } + else { + result = cuddZddSymmSiftingBackward(table, move_up, + initial_size); + /* move backward and stop at best position */ + } + if (!result) + goto cuddZddSymmSiftingConvAuxOutOfMem; + } + else { /* moving up first:shorter */ + /* Find top of x's symmetry group */ + x = table->subtableZ[x].next; + + move_up = cuddZddSymmSifting_up(table, x, x_low, initial_size); + /* after that point x --> x_high, unless early term */ + if (move_up == ZDD_MV_OOM) + goto cuddZddSymmSiftingConvAuxOutOfMem; + + if (move_up != NULL) { + x = move_up->x; + } + else { + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + } + i = table->subtableZ[x].next; + init_group_size = x - i + 1; + + move_down = cuddZddSymmSifting_down(table, x, x_high, + initial_size); + if (move_down == ZDD_MV_OOM) + goto cuddZddSymmSiftingConvAuxOutOfMem; + + if (move_down == NULL || + table->subtableZ[move_down->y].next != move_down->y) { + /* symmetry detected may have to make another complete + pass */ + if (move_down != NULL) { + x = move_down->y; + } + else { + while ((unsigned) x < table->subtableZ[x].next) + x = table->subtableZ[x].next; + x = table->subtableZ[x].next; + } + i = x; + while ((unsigned) i < table->subtableZ[i].next) { + i = table->subtableZ[i].next; + } + final_group_size = i - x + 1; + + if (init_group_size == final_group_size) { + /* No new symmetries detected, + go back to best position */ + result = cuddZddSymmSiftingBackward(table, move_down, + initial_size); + } + else { + while (move_up != NULL) { + move = move_up->next; + cuddDeallocNode(table, (DdNode *)move_up); + move_up = move; + } + initial_size = table->keysZ; + move_up = cuddZddSymmSifting_up(table, x, x_low, + initial_size); + result = cuddZddSymmSiftingBackward(table, move_up, + initial_size); + } + } + else { + result = cuddZddSymmSiftingBackward(table, move_down, + initial_size); + /* move backward and stop at best position */ + } + if (!result) + goto cuddZddSymmSiftingConvAuxOutOfMem; + } + + while (move_down != NULL) { + move = move_down->next; + cuddDeallocNode(table, (DdNode *)move_down); + move_down = move; + } + while (move_up != NULL) { + move = move_up->next; + cuddDeallocNode(table, (DdNode *)move_up); + move_up = move; + } + + return(1); + +cuddZddSymmSiftingConvAuxOutOfMem: + if (move_down != ZDD_MV_OOM) { + while (move_down != NULL) { + move = move_down->next; + cuddDeallocNode(table, (DdNode *)move_down); + move_down = move; + } + } + if (move_up != ZDD_MV_OOM) { + while (move_up != NULL) { + move = move_up->next; + cuddDeallocNode(table, (DdNode *)move_up); + move_up = move; + } + } + + return(0); + +} /* end of cuddZddSymmSiftingConvAux */ + + +/**Function******************************************************************** + + Synopsis [Moves x up until either it reaches the bound (x_low) or + the size of the ZDD heap increases too much.] + + Description [Moves x up until either it reaches the bound (x_low) or + the size of the ZDD heap increases too much. Assumes that x is the top + of a symmetry group. Checks x for symmetry to the adjacent + variables. If symmetry is found, the symmetry group of x is merged + with the symmetry group of the other variable. Returns the set of + moves in case of success; ZDD_MV_OOM if memory is full.] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +static Move * +cuddZddSymmSifting_up( + DdManager * table, + int x, + int x_low, + int initial_size) +{ + Move *moves; + Move *move; + int y; + int size; + int limit_size = initial_size; + int i, gytop; + + moves = NULL; + y = cuddZddNextLow(table, x); + while (y >= x_low) { + gytop = table->subtableZ[y].next; + if (cuddZddSymmCheck(table, y, x)) { + /* Symmetry found, attach symm groups */ + table->subtableZ[y].next = x; + i = table->subtableZ[x].next; + while (table->subtableZ[i].next != (unsigned) x) + i = table->subtableZ[i].next; + table->subtableZ[i].next = gytop; + } + else if ((table->subtableZ[x].next == (unsigned) x) && + (table->subtableZ[y].next == (unsigned) y)) { + /* x and y have self symmetry */ + size = cuddZddSwapInPlace(table, y, x); + if (size == 0) + goto cuddZddSymmSifting_upOutOfMem; + move = (Move *)cuddDynamicAllocNode(table); + if (move == NULL) + goto cuddZddSymmSifting_upOutOfMem; + move->x = y; + move->y = x; + move->size = size; + move->next = moves; + moves = move; + if ((double)size > + (double)limit_size * table->maxGrowth) + return(moves); + if (size < limit_size) + limit_size = size; + } + else { /* Group move */ + size = zdd_group_move(table, y, x, &moves); + if ((double)size > + (double)limit_size * table->maxGrowth) + return(moves); + if (size < limit_size) + limit_size = size; + } + x = gytop; + y = cuddZddNextLow(table, x); + } + + return(moves); + +cuddZddSymmSifting_upOutOfMem: + while (moves != NULL) { + move = moves->next; + cuddDeallocNode(table, (DdNode *)moves); + moves = move; + } + return(ZDD_MV_OOM); + +} /* end of cuddZddSymmSifting_up */ + + +/**Function******************************************************************** + + Synopsis [Moves x down until either it reaches the bound (x_high) or + the size of the ZDD heap increases too much.] + + Description [Moves x down until either it reaches the bound (x_high) + or the size of the ZDD heap increases too much. Assumes that x is the + bottom of a symmetry group. Checks x for symmetry to the adjacent + variables. If symmetry is found, the symmetry group of x is merged + with the symmetry group of the other variable. Returns the set of + moves in case of success; ZDD_MV_OOM if memory is full.] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +static Move * +cuddZddSymmSifting_down( + DdManager * table, + int x, + int x_high, + int initial_size) +{ + Move *moves; + Move *move; + int y; + int size; + int limit_size = initial_size; + int i, gxtop, gybot; + + moves = NULL; + y = cuddZddNextHigh(table, x); + while (y <= x_high) { + gybot = table->subtableZ[y].next; + while (table->subtableZ[gybot].next != (unsigned) y) + gybot = table->subtableZ[gybot].next; + if (cuddZddSymmCheck(table, x, y)) { + /* Symmetry found, attach symm groups */ + gxtop = table->subtableZ[x].next; + table->subtableZ[x].next = y; + i = table->subtableZ[y].next; + while (table->subtableZ[i].next != (unsigned) y) + i = table->subtableZ[i].next; + table->subtableZ[i].next = gxtop; + } + else if ((table->subtableZ[x].next == (unsigned) x) && + (table->subtableZ[y].next == (unsigned) y)) { + /* x and y have self symmetry */ + size = cuddZddSwapInPlace(table, x, y); + if (size == 0) + goto cuddZddSymmSifting_downOutOfMem; + move = (Move *)cuddDynamicAllocNode(table); + if (move == NULL) + goto cuddZddSymmSifting_downOutOfMem; + move->x = x; + move->y = y; + move->size = size; + move->next = moves; + moves = move; + if ((double)size > + (double)limit_size * table->maxGrowth) + return(moves); + if (size < limit_size) + limit_size = size; + x = y; + y = cuddZddNextHigh(table, x); + } + else { /* Group move */ + size = zdd_group_move(table, x, y, &moves); + if ((double)size > + (double)limit_size * table->maxGrowth) + return(moves); + if (size < limit_size) + limit_size = size; + } + x = gybot; + y = cuddZddNextHigh(table, x); + } + + return(moves); + +cuddZddSymmSifting_downOutOfMem: + while (moves != NULL) { + move = moves->next; + cuddDeallocNode(table, (DdNode *)moves); + moves = move; + } + return(ZDD_MV_OOM); + +} /* end of cuddZddSymmSifting_down */ + + +/**Function******************************************************************** + + Synopsis [Given a set of moves, returns the ZDD heap to the position + giving the minimum size.] + + Description [Given a set of moves, returns the ZDD heap to the + position giving the minimum size. In case of ties, returns to the + closest position giving the minimum size. Returns 1 in case of + success; 0 otherwise.] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +static int +cuddZddSymmSiftingBackward( + DdManager * table, + Move * moves, + int size) +{ + int i; + int i_best; + Move *move; + int res; + + i_best = -1; + for (move = moves, i = 0; move != NULL; move = move->next, i++) { + if (move->size < size) { + i_best = i; + size = move->size; + } + } + + for (move = moves, i = 0; move != NULL; move = move->next, i++) { + if (i == i_best) break; + if ((table->subtableZ[move->x].next == move->x) && + (table->subtableZ[move->y].next == move->y)) { + res = cuddZddSwapInPlace(table, move->x, move->y); + if (!res) return(0); + } + else { /* Group move necessary */ + res = zdd_group_move_backward(table, move->x, move->y); + } + if (i_best == -1 && res == size) + break; + } + + return(1); + +} /* end of cuddZddSymmSiftingBackward */ + + +/**Function******************************************************************** + + Synopsis [Swaps two groups.] + + Description [Swaps two groups. x is assumed to be the bottom variable + of the first group. y is assumed to be the top variable of the second + group. Updates the list of moves. Returns the number of keys in the + table if successful; 0 otherwise.] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +static int +zdd_group_move( + DdManager * table, + int x, + int y, + Move ** moves) +{ + Move *move; + int size; + int i, temp, gxtop, gxbot, gytop, gybot, yprev; + int swapx, swapy; + +#ifdef DD_DEBUG + assert(x < y); /* we assume that x < y */ +#endif + /* Find top and bottom for the two groups. */ + gxtop = table->subtableZ[x].next; + gytop = y; + gxbot = x; + gybot = table->subtableZ[y].next; + while (table->subtableZ[gybot].next != (unsigned) y) + gybot = table->subtableZ[gybot].next; + yprev = gybot; + + while (x <= y) { + while (y > gxtop) { + /* Set correct symmetries. */ + temp = table->subtableZ[x].next; + if (temp == x) + temp = y; + i = gxtop; + for (;;) { + if (table->subtableZ[i].next == (unsigned) x) { + table->subtableZ[i].next = y; + break; + } else { + i = table->subtableZ[i].next; + } + } + if (table->subtableZ[y].next != (unsigned) y) { + table->subtableZ[x].next = table->subtableZ[y].next; + } else { + table->subtableZ[x].next = x; + } + + if (yprev != y) { + table->subtableZ[yprev].next = x; + } else { + yprev = x; + } + table->subtableZ[y].next = temp; + + size = cuddZddSwapInPlace(table, x, y); + if (size == 0) + goto zdd_group_moveOutOfMem; + swapx = x; + swapy = y; + y = x; + x--; + } /* while y > gxtop */ + + /* Trying to find the next y. */ + if (table->subtableZ[y].next <= (unsigned) y) { + gybot = y; + } else { + y = table->subtableZ[y].next; + } + + yprev = gxtop; + gxtop++; + gxbot++; + x = gxbot; + } /* while x <= y, end of group movement */ + move = (Move *)cuddDynamicAllocNode(table); + if (move == NULL) + goto zdd_group_moveOutOfMem; + move->x = swapx; + move->y = swapy; + move->size = table->keysZ; + move->next = *moves; + *moves = move; + + return(table->keysZ); + +zdd_group_moveOutOfMem: + while (*moves != NULL) { + move = (*moves)->next; + cuddDeallocNode(table, (DdNode *)(*moves)); + *moves = move; + } + return(0); + +} /* end of zdd_group_move */ + + +/**Function******************************************************************** + + Synopsis [Undoes the swap of two groups.] + + Description [Undoes the swap of two groups. x is assumed to be the + bottom variable of the first group. y is assumed to be the top + variable of the second group. Returns 1 if successful; 0 otherwise.] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +static int +zdd_group_move_backward( + DdManager * table, + int x, + int y) +{ + int size; + int i, temp, gxtop, gxbot, gytop, gybot, yprev; + +#ifdef DD_DEBUG + assert(x < y); /* we assume that x < y */ +#endif + /* Find top and bottom of the two groups. */ + gxtop = table->subtableZ[x].next; + gytop = y; + gxbot = x; + gybot = table->subtableZ[y].next; + while (table->subtableZ[gybot].next != (unsigned) y) + gybot = table->subtableZ[gybot].next; + yprev = gybot; + + while (x <= y) { + while (y > gxtop) { + /* Set correct symmetries. */ + temp = table->subtableZ[x].next; + if (temp == x) + temp = y; + i = gxtop; + for (;;) { + if (table->subtableZ[i].next == (unsigned) x) { + table->subtableZ[i].next = y; + break; + } else { + i = table->subtableZ[i].next; + } + } + if (table->subtableZ[y].next != (unsigned) y) { + table->subtableZ[x].next = table->subtableZ[y].next; + } else { + table->subtableZ[x].next = x; + } + + if (yprev != y) { + table->subtableZ[yprev].next = x; + } else { + yprev = x; + } + table->subtableZ[y].next = temp; + + size = cuddZddSwapInPlace(table, x, y); + if (size == 0) + return(0); + y = x; + x--; + } /* while y > gxtop */ + + /* Trying to find the next y. */ + if (table->subtableZ[y].next <= (unsigned) y) { + gybot = y; + } else { + y = table->subtableZ[y].next; + } + + yprev = gxtop; + gxtop++; + gxbot++; + x = gxbot; + } /* while x <= y, end of group movement backward */ + + return(size); + +} /* end of zdd_group_move_backward */ + + +/**Function******************************************************************** + + Synopsis [Counts numbers of symmetric variables and symmetry + groups.] + + Description [] + + SideEffects [None] + +******************************************************************************/ +static void +cuddZddSymmSummary( + DdManager * table, + int lower, + int upper, + int * symvars, + int * symgroups) +{ + int i,x,gbot; + int TotalSymm = 0; + int TotalSymmGroups = 0; + + for (i = lower; i <= upper; i++) { + if (table->subtableZ[i].next != (unsigned) i) { + TotalSymmGroups++; + x = i; + do { + TotalSymm++; + gbot = x; + x = table->subtableZ[x].next; + } while (x != i); +#ifdef DD_DEBUG + assert(table->subtableZ[gbot].next == (unsigned) i); +#endif + i = gbot; + } + } + *symvars = TotalSymm; + *symgroups = TotalSymmGroups; + + return; + +} /* end of cuddZddSymmSummary */ + |