diff options
Diffstat (limited to 'src/misc/espresso/exact.c')
| -rw-r--r-- | src/misc/espresso/exact.c | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/src/misc/espresso/exact.c b/src/misc/espresso/exact.c new file mode 100644 index 00000000..b1943636 --- /dev/null +++ b/src/misc/espresso/exact.c @@ -0,0 +1,181 @@ +/* + * Revision Control Information + * + * $Source$ + * $Author$ + * $Revision$ + * $Date$ + * + */ +#include "espresso.h" + + +static void dump_irredundant(); +static pcover do_minimize(); + + +/* + * minimize_exact -- main entry point for exact minimization + * + * Global flags which affect this routine are: + * + * debug + * skip_make_sparse + */ + +pcover +minimize_exact(F, D, R, exact_cover) +pcover F, D, R; +int exact_cover; +{ + return do_minimize(F, D, R, exact_cover, /*weighted*/ 0); +} + + +pcover +minimize_exact_literals(F, D, R, exact_cover) +pcover F, D, R; +int exact_cover; +{ + return do_minimize(F, D, R, exact_cover, /*weighted*/ 1); +} + + + +static pcover +do_minimize(F, D, R, exact_cover, weighted) +pcover F, D, R; +int exact_cover; +int weighted; +{ + pcover newF, E, Rt, Rp; + pset p, last; + int heur, level, *weights, i; + sm_matrix *table; + sm_row *cover; + sm_element *pe; + int debug_save = debug; + + if (debug & EXACT) { + debug |= (IRRED | MINCOV); + } +#if defined(sun) || defined(bsd4_2) /* hack ... */ + if (debug & MINCOV) { + setlinebuf(stdout); + } +#endif + level = (debug & MINCOV) ? 4 : 0; + heur = ! exact_cover; + + /* Generate all prime implicants */ + EXEC(F = primes_consensus(cube2list(F, D)), "PRIMES ", F); + + /* Setup the prime implicant table */ + EXEC(irred_split_cover(F, D, &E, &Rt, &Rp), "ESSENTIALS ", E); + EXEC(table = irred_derive_table(D, E, Rp), "PI-TABLE ", Rp); + + /* Solve either a weighted or nonweighted covering problem */ + if (weighted) { + /* correct only for all 2-valued variables */ + weights = ALLOC(int, F->count); + foreach_set(Rp, last, p) { + weights[SIZE(p)] = cube.size - set_ord(p); + /* We have added the 0's in the output part instead of the 1's. + This loop corrects the literal count. */ + for (i = cube.first_part[cube.output]; + i <= cube.last_part[cube.output]; i++) { + is_in_set(p, i) ? weights[SIZE(p)]++ : weights[SIZE(p)]--; + } + } + } else { + weights = NIL(int); + } + EXEC(cover=sm_minimum_cover(table,weights,heur,level), "MINCOV ", F); + if (weights != 0) { + FREE(weights); + } + + if (debug & EXACT) { + dump_irredundant(E, Rt, Rp, table); + } + + /* Form the result cover */ + newF = new_cover(100); + foreach_set(E, last, p) { + newF = sf_addset(newF, p); + } + sm_foreach_row_element(cover, pe) { + newF = sf_addset(newF, GETSET(F, pe->col_num)); + } + + free_cover(E); + free_cover(Rt); + free_cover(Rp); + sm_free(table); + sm_row_free(cover); + free_cover(F); + + /* Attempt to make the results more sparse */ + debug &= ~ (IRRED | SHARP | MINCOV); + if (! skip_make_sparse && R != 0) { + newF = make_sparse(newF, D, R); + } + + debug = debug_save; + return newF; +} + +static void +dump_irredundant(E, Rt, Rp, table) +pcover E, Rt, Rp; +sm_matrix *table; +{ + FILE *fp_pi_table, *fp_primes; + pPLA PLA; + pset last, p; + char *file; + + if (filename == 0 || strcmp(filename, "(stdin)") == 0) { + fp_pi_table = fp_primes = stdout; + } else { + file = ALLOC(char, strlen(filename)+20); + (void) sprintf(file, "%s.primes", filename); + if ((fp_primes = fopen(file, "w")) == NULL) { + (void) fprintf(stderr, "espresso: Unable to open %s\n", file); + fp_primes = stdout; + } + (void) sprintf(file, "%s.pi", filename); + if ((fp_pi_table = fopen(file, "w")) == NULL) { + (void) fprintf(stderr, "espresso: Unable to open %s\n", file); + fp_pi_table = stdout; + } + FREE(file); + } + + PLA = new_PLA(); + PLA_labels(PLA); + + fpr_header(fp_primes, PLA, F_type); + free_PLA(PLA); + + (void) fprintf(fp_primes, "# Essential primes are\n"); + foreach_set(E, last, p) { + (void) fprintf(fp_primes, "%s\n", pc1(p)); + } + (void) fprintf(fp_primes, "# Totally redundant primes are\n"); + foreach_set(Rt, last, p) { + (void) fprintf(fp_primes, "%s\n", pc1(p)); + } + (void) fprintf(fp_primes, "# Partially redundant primes are\n"); + foreach_set(Rp, last, p) { + (void) fprintf(fp_primes, "%s\n", pc1(p)); + } + if (fp_primes != stdout) { + (void) fclose(fp_primes); + } + + sm_write(fp_pi_table, table); + if (fp_pi_table != stdout) { + (void) fclose(fp_pi_table); + } +} |