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Diffstat (limited to 'abc70930/src/misc/espresso/compl.c')
-rw-r--r-- | abc70930/src/misc/espresso/compl.c | 680 |
1 files changed, 680 insertions, 0 deletions
diff --git a/abc70930/src/misc/espresso/compl.c b/abc70930/src/misc/espresso/compl.c new file mode 100644 index 00000000..8f1c6606 --- /dev/null +++ b/abc70930/src/misc/espresso/compl.c @@ -0,0 +1,680 @@ +/* + * Revision Control Information + * + * $Source$ + * $Author$ + * $Revision$ + * $Date$ + * + */ +/* + * module: compl.c + * purpose: compute the complement of a multiple-valued function + * + * The "unate recursive paradigm" is used. After a set of special + * cases are examined, the function is split on the "most active + * variable". These two halves are complemented recursively, and then + * the results are merged. + * + * Changes (from Version 2.1 to Version 2.2) + * 1. Minor bug in compl_lifting -- cubes in the left half were + * not marked as active, so that when merging a leaf from the left + * hand side, the active flags were essentially random. This led + * to minor impredictability problem, but never affected the + * accuracy of the results. + */ + +#include "espresso.h" + +#define USE_COMPL_LIFT 0 +#define USE_COMPL_LIFT_ONSET 1 +#define USE_COMPL_LIFT_ONSET_COMPLEX 2 +#define NO_LIFTING 3 + +static bool compl_special_cases(); +static pcover compl_merge(); +static void compl_d1merge(); +static pcover compl_cube(); +static void compl_lift(); +static void compl_lift_onset(); +static void compl_lift_onset_complex(); +static bool simp_comp_special_cases(); +static bool simplify_special_cases(); + + +/* complement -- compute the complement of T */ +pcover complement(T) +pcube *T; /* T will be disposed of */ +{ + register pcube cl, cr; + register int best; + pcover Tbar, Tl, Tr; + int lifting; + static int compl_level = 0; + + if (debug & COMPL) + debug_print(T, "COMPLEMENT", compl_level++); + + if (compl_special_cases(T, &Tbar) == MAYBE) { + + /* Allocate space for the partition cubes */ + cl = new_cube(); + cr = new_cube(); + best = binate_split_select(T, cl, cr, COMPL); + + /* Complement the left and right halves */ + Tl = complement(scofactor(T, cl, best)); + Tr = complement(scofactor(T, cr, best)); + + if (Tr->count*Tl->count > (Tr->count+Tl->count)*CUBELISTSIZE(T)) { + lifting = USE_COMPL_LIFT_ONSET; + } else { + lifting = USE_COMPL_LIFT; + } + Tbar = compl_merge(T, Tl, Tr, cl, cr, best, lifting); + + free_cube(cl); + free_cube(cr); + free_cubelist(T); + } + + if (debug & COMPL) + debug1_print(Tbar, "exit COMPLEMENT", --compl_level); + return Tbar; +} + +static bool compl_special_cases(T, Tbar) +pcube *T; /* will be disposed if answer is determined */ +pcover *Tbar; /* returned only if answer determined */ +{ + register pcube *T1, p, ceil, cof=T[0]; + pcover A, ceil_compl; + + /* Check for no cubes in the cover */ + if (T[2] == NULL) { + *Tbar = sf_addset(new_cover(1), cube.fullset); + free_cubelist(T); + return TRUE; + } + + /* Check for only a single cube in the cover */ + if (T[3] == NULL) { + *Tbar = compl_cube(set_or(cof, cof, T[2])); + free_cubelist(T); + return TRUE; + } + + /* Check for a row of all 1's (implies complement is null) */ + for(T1 = T+2; (p = *T1++) != NULL; ) { + if (full_row(p, cof)) { + *Tbar = new_cover(0); + free_cubelist(T); + return TRUE; + } + } + + /* Check for a column of all 0's which can be factored out */ + ceil = set_save(cof); + for(T1 = T+2; (p = *T1++) != NULL; ) { + INLINEset_or(ceil, ceil, p); + } + if (! setp_equal(ceil, cube.fullset)) { + ceil_compl = compl_cube(ceil); + (void) set_or(cof, cof, set_diff(ceil, cube.fullset, ceil)); + set_free(ceil); + *Tbar = sf_append(complement(T), ceil_compl); + return TRUE; + } + set_free(ceil); + + /* Collect column counts, determine unate variables, etc. */ + massive_count(T); + + /* If single active variable not factored out above, then tautology ! */ + if (cdata.vars_active == 1) { + *Tbar = new_cover(0); + free_cubelist(T); + return TRUE; + + /* Check for unate cover */ + } else if (cdata.vars_unate == cdata.vars_active) { + A = map_cover_to_unate(T); + free_cubelist(T); + A = unate_compl(A); + *Tbar = map_unate_to_cover(A); + sf_free(A); + return TRUE; + + /* Not much we can do about it */ + } else { + return MAYBE; + } +} + +/* + * compl_merge -- merge the two cofactors around the splitting + * variable + * + * The merge operation involves intersecting each cube of the left + * cofactor with cl, and intersecting each cube of the right cofactor + * with cr. The union of these two covers is the merged result. + * + * In order to reduce the number of cubes, a distance-1 merge is + * performed (note that two cubes can only combine distance-1 in the + * splitting variable). Also, a simple expand is performed in the + * splitting variable (simple implies the covering check for the + * expansion is not full containment, but single-cube containment). + */ + +static pcover compl_merge(T1, L, R, cl, cr, var, lifting) +pcube *T1; /* Original ON-set */ +pcover L, R; /* Complement from each recursion branch */ +register pcube cl, cr; /* cubes used for cofactoring */ +int var; /* splitting variable */ +int lifting; /* whether to perform lifting or not */ +{ + register pcube p, last, pt; + pcover T, Tbar; + pcube *L1, *R1; + + if (debug & COMPL) { + (void) printf("compl_merge: left %d, right %d\n", L->count, R->count); + (void) printf("%s (cl)\n%s (cr)\nLeft is\n", pc1(cl), pc2(cr)); + cprint(L); + (void) printf("Right is\n"); + cprint(R); + } + + /* Intersect each cube with the cofactored cube */ + foreach_set(L, last, p) { + INLINEset_and(p, p, cl); + SET(p, ACTIVE); + } + foreach_set(R, last, p) { + INLINEset_and(p, p, cr); + SET(p, ACTIVE); + } + + /* Sort the arrays for a distance-1 merge */ + (void) set_copy(cube.temp[0], cube.var_mask[var]); + qsort((char *) (L1 = sf_list(L)), L->count, sizeof(pset), (int (*)()) d1_order); + qsort((char *) (R1 = sf_list(R)), R->count, sizeof(pset), (int (*)()) d1_order); + + /* Perform distance-1 merge */ + compl_d1merge(L1, R1); + + /* Perform lifting */ + switch(lifting) { + case USE_COMPL_LIFT_ONSET: + T = cubeunlist(T1); + compl_lift_onset(L1, T, cr, var); + compl_lift_onset(R1, T, cl, var); + free_cover(T); + break; + case USE_COMPL_LIFT_ONSET_COMPLEX: + T = cubeunlist(T1); + compl_lift_onset_complex(L1, T, var); + compl_lift_onset_complex(R1, T, var); + free_cover(T); + break; + case USE_COMPL_LIFT: + compl_lift(L1, R1, cr, var); + compl_lift(R1, L1, cl, var); + break; + case NO_LIFTING: + break; + default: + ; + } + FREE(L1); + FREE(R1); + + /* Re-create the merged cover */ + Tbar = new_cover(L->count + R->count); + pt = Tbar->data; + foreach_set(L, last, p) { + INLINEset_copy(pt, p); + Tbar->count++; + pt += Tbar->wsize; + } + foreach_active_set(R, last, p) { + INLINEset_copy(pt, p); + Tbar->count++; + pt += Tbar->wsize; + } + + if (debug & COMPL) { + (void) printf("Result %d\n", Tbar->count); + if (verbose_debug) + cprint(Tbar); + } + + free_cover(L); + free_cover(R); + return Tbar; +} + +/* + * compl_lift_simple -- expand in the splitting variable using single + * cube containment against the other recursion branch to check + * validity of the expansion, and expanding all (or none) of the + * splitting variable. + */ +static void compl_lift(A1, B1, bcube, var) +pcube *A1, *B1, bcube; +int var; +{ + register pcube a, b, *B2, lift=cube.temp[4], liftor=cube.temp[5]; + pcube mask = cube.var_mask[var]; + + (void) set_and(liftor, bcube, mask); + + /* for each cube in the first array ... */ + for(; (a = *A1++) != NULL; ) { + if (TESTP(a, ACTIVE)) { + + /* create a lift of this cube in the merging coord */ + (void) set_merge(lift, bcube, a, mask); + + /* for each cube in the second array */ + for(B2 = B1; (b = *B2++) != NULL; ) { + INLINEsetp_implies(lift, b, /* when_false => */ continue); + /* when_true => fall through to next statement */ + + /* cube of A1 was contained by some cube of B1, so raise */ + INLINEset_or(a, a, liftor); + break; + } + } + } +} + + + +/* + * compl_lift_onset -- expand in the splitting variable using a + * distance-1 check against the original on-set; expand all (or + * none) of the splitting variable. Each cube of A1 is expanded + * against the original on-set T. + */ +static void compl_lift_onset(A1, T, bcube, var) +pcube *A1; +pcover T; +pcube bcube; +int var; +{ + register pcube a, last, p, lift=cube.temp[4], mask=cube.var_mask[var]; + + /* for each active cube from one branch of the complement */ + for(; (a = *A1++) != NULL; ) { + if (TESTP(a, ACTIVE)) { + + /* create a lift of this cube in the merging coord */ + INLINEset_and(lift, bcube, mask); /* isolate parts to raise */ + INLINEset_or(lift, a, lift); /* raise these parts in a */ + + /* for each cube in the ON-set, check for intersection */ + foreach_set(T, last, p) { + if (cdist0(p, lift)) { + goto nolift; + } + } + INLINEset_copy(a, lift); /* save the raising */ + SET(a, ACTIVE); +nolift : ; + } + } +} + +/* + * compl_lift_complex -- expand in the splitting variable, but expand all + * parts which can possibly expand. + * T is the original ON-set + * A1 is either the left or right cofactor + */ +static void compl_lift_onset_complex(A1, T, var) +pcube *A1; /* array of pointers to new result */ +pcover T; /* original ON-set */ +int var; /* which variable we split on */ +{ + register int dist; + register pcube last, p, a, xlower; + + /* for each cube in the complement */ + xlower = new_cube(); + for(; (a = *A1++) != NULL; ) { + + if (TESTP(a, ACTIVE)) { + + /* Find which parts of the splitting variable are forced low */ + INLINEset_clear(xlower, cube.size); + foreach_set(T, last, p) { + if ((dist = cdist01(p, a)) < 2) { + if (dist == 0) { + fatal("compl: ON-set and OFF-set are not orthogonal"); + } else { + (void) force_lower(xlower, p, a); + } + } + } + + (void) set_diff(xlower, cube.var_mask[var], xlower); + (void) set_or(a, a, xlower); + free_cube(xlower); + } + } +} + + + +/* + * compl_d1merge -- distance-1 merge in the splitting variable + */ +static void compl_d1merge(L1, R1) +register pcube *L1, *R1; +{ + register pcube pl, pr; + + /* Find equal cubes between the two cofactors */ + for(pl = *L1, pr = *R1; (pl != NULL) && (pr != NULL); ) + switch (d1_order(L1, R1)) { + case 1: + pr = *(++R1); break; /* advance right pointer */ + case -1: + pl = *(++L1); break; /* advance left pointer */ + case 0: + RESET(pr, ACTIVE); + INLINEset_or(pl, pl, pr); + pr = *(++R1); + default: + ; + } +} + + + +/* compl_cube -- return the complement of a single cube (De Morgan's law) */ +static pcover compl_cube(p) +register pcube p; +{ + register pcube diff=cube.temp[7], pdest, mask, full=cube.fullset; + int var; + pcover R; + + /* Allocate worst-case size cover (to avoid checking overflow) */ + R = new_cover(cube.num_vars); + + /* Compute bit-wise complement of the cube */ + INLINEset_diff(diff, full, p); + + for(var = 0; var < cube.num_vars; var++) { + mask = cube.var_mask[var]; + /* If the bit-wise complement is not empty in var ... */ + if (! setp_disjoint(diff, mask)) { + pdest = GETSET(R, R->count++); + INLINEset_merge(pdest, diff, full, mask); + } + } + return R; +} + +/* simp_comp -- quick simplification of T */ +void simp_comp(T, Tnew, Tbar) +pcube *T; /* T will be disposed of */ +pcover *Tnew; +pcover *Tbar; +{ + register pcube cl, cr; + register int best; + pcover Tl, Tr, Tlbar, Trbar; + int lifting; + static int simplify_level = 0; + + if (debug & COMPL) + debug_print(T, "SIMPCOMP", simplify_level++); + + if (simp_comp_special_cases(T, Tnew, Tbar) == MAYBE) { + + /* Allocate space for the partition cubes */ + cl = new_cube(); + cr = new_cube(); + best = binate_split_select(T, cl, cr, COMPL); + + /* Complement the left and right halves */ + simp_comp(scofactor(T, cl, best), &Tl, &Tlbar); + simp_comp(scofactor(T, cr, best), &Tr, &Trbar); + + lifting = USE_COMPL_LIFT; + *Tnew = compl_merge(T, Tl, Tr, cl, cr, best, lifting); + + lifting = USE_COMPL_LIFT; + *Tbar = compl_merge(T, Tlbar, Trbar, cl, cr, best, lifting); + + /* All of this work for nothing ? Let's hope not ... */ + if ((*Tnew)->count > CUBELISTSIZE(T)) { + sf_free(*Tnew); + *Tnew = cubeunlist(T); + } + + free_cube(cl); + free_cube(cr); + free_cubelist(T); + } + + if (debug & COMPL) { + debug1_print(*Tnew, "exit SIMPCOMP (new)", simplify_level); + debug1_print(*Tbar, "exit SIMPCOMP (compl)", simplify_level); + simplify_level--; + } +} + +static bool simp_comp_special_cases(T, Tnew, Tbar) +pcube *T; /* will be disposed if answer is determined */ +pcover *Tnew; /* returned only if answer determined */ +pcover *Tbar; /* returned only if answer determined */ +{ + register pcube *T1, p, ceil, cof=T[0]; + pcube last; + pcover A; + + /* Check for no cubes in the cover (function is empty) */ + if (T[2] == NULL) { + *Tnew = new_cover(1); + *Tbar = sf_addset(new_cover(1), cube.fullset); + free_cubelist(T); + return TRUE; + } + + /* Check for only a single cube in the cover */ + if (T[3] == NULL) { + (void) set_or(cof, cof, T[2]); + *Tnew = sf_addset(new_cover(1), cof); + *Tbar = compl_cube(cof); + free_cubelist(T); + return TRUE; + } + + /* Check for a row of all 1's (function is a tautology) */ + for(T1 = T+2; (p = *T1++) != NULL; ) { + if (full_row(p, cof)) { + *Tnew = sf_addset(new_cover(1), cube.fullset); + *Tbar = new_cover(1); + free_cubelist(T); + return TRUE; + } + } + + /* Check for a column of all 0's which can be factored out */ + ceil = set_save(cof); + for(T1 = T+2; (p = *T1++) != NULL; ) { + INLINEset_or(ceil, ceil, p); + } + if (! setp_equal(ceil, cube.fullset)) { + p = new_cube(); + (void) set_diff(p, cube.fullset, ceil); + (void) set_or(cof, cof, p); + set_free(p); + simp_comp(T, Tnew, Tbar); + + /* Adjust the ON-set */ + A = *Tnew; + foreach_set(A, last, p) { + INLINEset_and(p, p, ceil); + } + + /* Compute the new complement */ + *Tbar = sf_append(*Tbar, compl_cube(ceil)); + set_free(ceil); + return TRUE; + } + set_free(ceil); + + /* Collect column counts, determine unate variables, etc. */ + massive_count(T); + + /* If single active variable not factored out above, then tautology ! */ + if (cdata.vars_active == 1) { + *Tnew = sf_addset(new_cover(1), cube.fullset); + *Tbar = new_cover(1); + free_cubelist(T); + return TRUE; + + /* Check for unate cover */ + } else if (cdata.vars_unate == cdata.vars_active) { + /* Make the cover minimum by single-cube containment */ + A = cubeunlist(T); + *Tnew = sf_contain(A); + + /* Now form a minimum representation of the complement */ + A = map_cover_to_unate(T); + A = unate_compl(A); + *Tbar = map_unate_to_cover(A); + sf_free(A); + free_cubelist(T); + return TRUE; + + /* Not much we can do about it */ + } else { + return MAYBE; + } +} + +/* simplify -- quick simplification of T */ +pcover simplify(T) +pcube *T; /* T will be disposed of */ +{ + register pcube cl, cr; + register int best; + pcover Tbar, Tl, Tr; + int lifting; + static int simplify_level = 0; + + if (debug & COMPL) { + debug_print(T, "SIMPLIFY", simplify_level++); + } + + if (simplify_special_cases(T, &Tbar) == MAYBE) { + + /* Allocate space for the partition cubes */ + cl = new_cube(); + cr = new_cube(); + + best = binate_split_select(T, cl, cr, COMPL); + + /* Complement the left and right halves */ + Tl = simplify(scofactor(T, cl, best)); + Tr = simplify(scofactor(T, cr, best)); + + lifting = USE_COMPL_LIFT; + Tbar = compl_merge(T, Tl, Tr, cl, cr, best, lifting); + + /* All of this work for nothing ? Let's hope not ... */ + if (Tbar->count > CUBELISTSIZE(T)) { + sf_free(Tbar); + Tbar = cubeunlist(T); + } + + free_cube(cl); + free_cube(cr); + free_cubelist(T); + } + + if (debug & COMPL) { + debug1_print(Tbar, "exit SIMPLIFY", --simplify_level); + } + return Tbar; +} + +static bool simplify_special_cases(T, Tnew) +pcube *T; /* will be disposed if answer is determined */ +pcover *Tnew; /* returned only if answer determined */ +{ + register pcube *T1, p, ceil, cof=T[0]; + pcube last; + pcover A; + + /* Check for no cubes in the cover */ + if (T[2] == NULL) { + *Tnew = new_cover(0); + free_cubelist(T); + return TRUE; + } + + /* Check for only a single cube in the cover */ + if (T[3] == NULL) { + *Tnew = sf_addset(new_cover(1), set_or(cof, cof, T[2])); + free_cubelist(T); + return TRUE; + } + + /* Check for a row of all 1's (implies function is a tautology) */ + for(T1 = T+2; (p = *T1++) != NULL; ) { + if (full_row(p, cof)) { + *Tnew = sf_addset(new_cover(1), cube.fullset); + free_cubelist(T); + return TRUE; + } + } + + /* Check for a column of all 0's which can be factored out */ + ceil = set_save(cof); + for(T1 = T+2; (p = *T1++) != NULL; ) { + INLINEset_or(ceil, ceil, p); + } + if (! setp_equal(ceil, cube.fullset)) { + p = new_cube(); + (void) set_diff(p, cube.fullset, ceil); + (void) set_or(cof, cof, p); + free_cube(p); + + A = simplify(T); + foreach_set(A, last, p) { + INLINEset_and(p, p, ceil); + } + *Tnew = A; + set_free(ceil); + return TRUE; + } + set_free(ceil); + + /* Collect column counts, determine unate variables, etc. */ + massive_count(T); + + /* If single active variable not factored out above, then tautology ! */ + if (cdata.vars_active == 1) { + *Tnew = sf_addset(new_cover(1), cube.fullset); + free_cubelist(T); + return TRUE; + + /* Check for unate cover */ + } else if (cdata.vars_unate == cdata.vars_active) { + A = cubeunlist(T); + *Tnew = sf_contain(A); + free_cubelist(T); + return TRUE; + + /* Not much we can do about it */ + } else { + return MAYBE; + } +} |