[6] | 1 | /* BDD library dump/undump routines */ |
---|
| 2 | |
---|
| 3 | |
---|
| 4 | #include "bddint.h" |
---|
| 5 | |
---|
| 6 | |
---|
| 7 | #define MAGIC_COOKIE 0x5e02f795l |
---|
| 8 | #define BDD_IOERROR 100 |
---|
| 9 | |
---|
| 10 | |
---|
| 11 | #define TRUE_ENCODING 0xffffff00l |
---|
| 12 | #define FALSE_ENCODING 0xffffff01l |
---|
| 13 | #define POSVAR_ENCODING 0xffffff02l |
---|
| 14 | #define NEGVAR_ENCODING 0xffffff03l |
---|
| 15 | #define POSNODE_ENCODING 0xffffff04l |
---|
| 16 | #define NEGNODE_ENCODING 0xffffff05l |
---|
| 17 | #define NODELABEL_ENCODING 0xffffff06l |
---|
| 18 | #define CONSTANT_ENCODING 0xffffff07l |
---|
| 19 | |
---|
| 20 | |
---|
| 21 | static |
---|
| 22 | int |
---|
| 23 | bytes_needed(long n) |
---|
| 24 | { |
---|
| 25 | if (n <= 0x100l) |
---|
| 26 | return (1); |
---|
| 27 | if (n <= 0x10000l) |
---|
| 28 | return (2); |
---|
| 29 | if (n <= 0x1000000l) |
---|
| 30 | return (3); |
---|
| 31 | return (4); |
---|
| 32 | } |
---|
| 33 | |
---|
| 34 | |
---|
| 35 | static |
---|
| 36 | void |
---|
| 37 | write(cmu_bdd_manager bddm, unsigned long n, int bytes, FILE *fp) |
---|
| 38 | { |
---|
| 39 | while (bytes) |
---|
| 40 | { |
---|
| 41 | if (fputc((char)(n >> (8*(bytes-1)) & 0xff), fp) == EOF) |
---|
| 42 | longjmp(bddm->abort.context, BDD_IOERROR); |
---|
| 43 | --bytes; |
---|
| 44 | } |
---|
| 45 | } |
---|
| 46 | |
---|
| 47 | |
---|
| 48 | static |
---|
| 49 | void |
---|
| 50 | cmu_bdd_dump_bdd_step(cmu_bdd_manager bddm, |
---|
| 51 | bdd f, |
---|
| 52 | FILE *fp, |
---|
| 53 | hash_table h, |
---|
| 54 | bdd_index_type *normalized_indexes, |
---|
| 55 | int index_size, |
---|
| 56 | int node_number_size) |
---|
| 57 | { |
---|
| 58 | int negated; |
---|
| 59 | long *number; |
---|
| 60 | |
---|
| 61 | BDD_SETUP(f); |
---|
| 62 | switch (cmu_bdd_type_aux(bddm, f)) |
---|
| 63 | { |
---|
| 64 | case BDD_TYPE_ZERO: |
---|
| 65 | write(bddm, FALSE_ENCODING, index_size+1, fp); |
---|
| 66 | break; |
---|
| 67 | case BDD_TYPE_ONE: |
---|
| 68 | write(bddm, TRUE_ENCODING, index_size+1, fp); |
---|
| 69 | break; |
---|
| 70 | case BDD_TYPE_CONSTANT: |
---|
| 71 | write(bddm, CONSTANT_ENCODING, index_size+1, fp); |
---|
| 72 | write(bddm, (unsigned long)BDD_DATA(f)[0], sizeof(long), fp); |
---|
| 73 | write(bddm, (unsigned long)BDD_DATA(f)[1], sizeof(long), fp); |
---|
| 74 | break; |
---|
| 75 | case BDD_TYPE_POSVAR: |
---|
| 76 | write(bddm, POSVAR_ENCODING, index_size+1, fp); |
---|
| 77 | write(bddm, (unsigned long)normalized_indexes[BDD_INDEX(bddm, f)], index_size, fp); |
---|
| 78 | break; |
---|
| 79 | case BDD_TYPE_NEGVAR: |
---|
| 80 | write(bddm, NEGVAR_ENCODING, index_size+1, fp); |
---|
| 81 | write(bddm, (unsigned long)normalized_indexes[BDD_INDEX(bddm, f)], index_size, fp); |
---|
| 82 | break; |
---|
| 83 | case BDD_TYPE_NONTERMINAL: |
---|
| 84 | if (bdd_lookup_in_hash_table(h, BDD_NOT(f))) |
---|
| 85 | { |
---|
| 86 | f=BDD_NOT(f); |
---|
| 87 | negated=1; |
---|
| 88 | } |
---|
| 89 | else |
---|
| 90 | negated=0; |
---|
| 91 | number=(long *)bdd_lookup_in_hash_table(h, f); |
---|
| 92 | if (number && *number < 0) |
---|
| 93 | { |
---|
| 94 | if (negated) |
---|
| 95 | write(bddm, NEGNODE_ENCODING, index_size+1, fp); |
---|
| 96 | else |
---|
| 97 | write(bddm, POSNODE_ENCODING, index_size+1, fp); |
---|
| 98 | write(bddm, (unsigned long)(-*number-1), node_number_size, fp); |
---|
| 99 | } |
---|
| 100 | else |
---|
| 101 | { |
---|
| 102 | if (number) |
---|
| 103 | { |
---|
| 104 | write(bddm, NODELABEL_ENCODING, index_size+1, fp); |
---|
| 105 | *number= -*number-1; |
---|
| 106 | } |
---|
| 107 | write(bddm, (unsigned long)normalized_indexes[BDD_INDEX(bddm, f)], index_size, fp); |
---|
| 108 | cmu_bdd_dump_bdd_step(bddm, BDD_THEN(f), fp, h, normalized_indexes, index_size, node_number_size); |
---|
| 109 | cmu_bdd_dump_bdd_step(bddm, BDD_ELSE(f), fp, h, normalized_indexes, index_size, node_number_size); |
---|
| 110 | } |
---|
| 111 | break; |
---|
| 112 | default: |
---|
| 113 | cmu_bdd_fatal("cmu_bdd_dump_bdd_step: unknown type returned by cmu_bdd_type"); |
---|
| 114 | } |
---|
| 115 | } |
---|
| 116 | |
---|
| 117 | |
---|
| 118 | int |
---|
| 119 | cmu_bdd_dump_bdd(cmu_bdd_manager bddm, bdd f, bdd *vars, FILE *fp) |
---|
| 120 | { |
---|
| 121 | long i; |
---|
| 122 | bdd_index_type *normalized_indexes; |
---|
| 123 | bdd_index_type v_index; |
---|
| 124 | bdd var; |
---|
| 125 | bdd_index_type number_vars; |
---|
| 126 | bdd *support; |
---|
| 127 | int ok; |
---|
| 128 | hash_table h; |
---|
| 129 | int index_size; |
---|
| 130 | long next; |
---|
| 131 | int node_number_size; |
---|
| 132 | |
---|
| 133 | if (bdd_check_arguments(1, f)) |
---|
| 134 | { |
---|
| 135 | for (i=0; vars[i]; ++i) |
---|
| 136 | if (cmu_bdd_type(bddm, vars[i]) != BDD_TYPE_POSVAR) |
---|
| 137 | { |
---|
| 138 | cmu_bdd_warning("cmu_bdd_dump_bdd: support is not all positive variables"); |
---|
| 139 | return (0); |
---|
| 140 | } |
---|
| 141 | normalized_indexes=(bdd_index_type *)mem_get_block((SIZE_T)(bddm->vars*sizeof(bdd_index_type))); |
---|
| 142 | for (i=0; i < bddm->vars; ++i) |
---|
| 143 | normalized_indexes[i]=BDD_MAX_INDEX; |
---|
| 144 | for (i=0; (var=vars[i]); ++i) |
---|
| 145 | { |
---|
| 146 | BDD_SETUP(var); |
---|
| 147 | v_index=BDD_INDEX(bddm, var); |
---|
| 148 | if (normalized_indexes[v_index] != BDD_MAX_INDEX) |
---|
| 149 | { |
---|
| 150 | cmu_bdd_warning("cmu_bdd_dump_bdd: variables duplicated in support"); |
---|
| 151 | mem_free_block((pointer)normalized_indexes); |
---|
| 152 | return (0); |
---|
| 153 | } |
---|
| 154 | normalized_indexes[v_index]=i; |
---|
| 155 | } |
---|
| 156 | number_vars=i; |
---|
| 157 | support=(bdd *)mem_get_block((SIZE_T)((bddm->vars+1)*sizeof(bdd))); |
---|
| 158 | cmu_bdd_support(bddm, f, support); |
---|
| 159 | ok=1; |
---|
| 160 | for (i=0; ok && (var=support[i]); ++i) |
---|
| 161 | { |
---|
| 162 | BDD_SETUP(var); |
---|
| 163 | if (normalized_indexes[BDD_INDEX(bddm, var)] == BDD_MAX_INDEX) |
---|
| 164 | { |
---|
| 165 | cmu_bdd_warning("cmu_bdd_dump_bdd: incomplete support specified"); |
---|
| 166 | ok=0; |
---|
| 167 | } |
---|
| 168 | } |
---|
| 169 | if (!ok) |
---|
| 170 | { |
---|
| 171 | mem_free_block((pointer)normalized_indexes); |
---|
| 172 | mem_free_block((pointer)support); |
---|
| 173 | return (0); |
---|
| 174 | } |
---|
| 175 | mem_free_block((pointer)support); |
---|
| 176 | /* Everything checked now; barring I/O errors, we should be able to */ |
---|
| 177 | /* write a valid output file. */ |
---|
| 178 | h=bdd_new_hash_table(bddm, sizeof(long)); |
---|
| 179 | FIREWALL1(bddm, |
---|
| 180 | if (retcode == BDD_IOERROR) |
---|
| 181 | { |
---|
| 182 | cmu_bdd_free_hash_table(h); |
---|
| 183 | mem_free_block((pointer)normalized_indexes); |
---|
| 184 | return (0); |
---|
| 185 | } |
---|
| 186 | else |
---|
| 187 | cmu_bdd_fatal("cmu_bdd_dump_bdd: got unexpected retcode"); |
---|
| 188 | ); |
---|
| 189 | index_size=bytes_needed(number_vars+1); |
---|
| 190 | bdd_mark_shared_nodes(bddm, f); |
---|
| 191 | next=0; |
---|
| 192 | bdd_number_shared_nodes(bddm, f, h, &next); |
---|
| 193 | node_number_size=bytes_needed(next); |
---|
| 194 | write(bddm, MAGIC_COOKIE, sizeof(long), fp); |
---|
| 195 | write(bddm, (unsigned long)number_vars, sizeof(bdd_index_type), fp); |
---|
| 196 | write(bddm, (unsigned long)next, sizeof(long), fp); |
---|
| 197 | cmu_bdd_dump_bdd_step(bddm, f, fp, h, normalized_indexes, index_size, node_number_size); |
---|
| 198 | cmu_bdd_free_hash_table(h); |
---|
| 199 | mem_free_block((pointer)normalized_indexes); |
---|
| 200 | return (1); |
---|
| 201 | } |
---|
| 202 | return (0); |
---|
| 203 | } |
---|
| 204 | |
---|
| 205 | |
---|
| 206 | static |
---|
| 207 | unsigned long |
---|
| 208 | read(int *error, int bytes, FILE *fp) |
---|
| 209 | { |
---|
| 210 | int c; |
---|
| 211 | long result; |
---|
| 212 | |
---|
| 213 | result=0; |
---|
| 214 | if (*error) |
---|
| 215 | return (result); |
---|
| 216 | while (bytes) |
---|
| 217 | { |
---|
| 218 | c=fgetc(fp); |
---|
| 219 | if (c == EOF) |
---|
| 220 | { |
---|
| 221 | if (ferror(fp)) |
---|
| 222 | *error=BDD_UNDUMP_IOERROR; |
---|
| 223 | else |
---|
| 224 | *error=BDD_UNDUMP_EOF; |
---|
| 225 | return (0l); |
---|
| 226 | } |
---|
| 227 | result=(result << 8)+c; |
---|
| 228 | --bytes; |
---|
| 229 | } |
---|
| 230 | return (result); |
---|
| 231 | } |
---|
| 232 | |
---|
| 233 | |
---|
| 234 | static long index_mask[]={0xffl, 0xffffl, 0xffffffl}; |
---|
| 235 | |
---|
| 236 | |
---|
| 237 | static |
---|
| 238 | bdd |
---|
| 239 | cmu_bdd_undump_bdd_step(cmu_bdd_manager bddm, |
---|
| 240 | bdd *vars, |
---|
| 241 | FILE *fp, |
---|
| 242 | bdd_index_type number_vars, |
---|
| 243 | bdd *shared, |
---|
| 244 | long number_shared, |
---|
| 245 | long *shared_so_far, |
---|
| 246 | int index_size, |
---|
| 247 | int node_number_size, |
---|
| 248 | int *error) |
---|
| 249 | { |
---|
| 250 | long node_number; |
---|
| 251 | long encoding; |
---|
| 252 | bdd_index_type i; |
---|
| 253 | INT_PTR value1, value2; |
---|
| 254 | bdd v; |
---|
| 255 | bdd temp1, temp2; |
---|
| 256 | bdd result; |
---|
| 257 | |
---|
| 258 | i=read(error, index_size, fp); |
---|
| 259 | if (*error) |
---|
| 260 | return ((bdd)0); |
---|
| 261 | if (i == index_mask[index_size-1]) |
---|
| 262 | { |
---|
| 263 | encoding=0xffffff00l+read(error, 1, fp); |
---|
| 264 | if (*error) |
---|
| 265 | return ((bdd)0); |
---|
| 266 | switch (encoding) |
---|
| 267 | { |
---|
| 268 | case TRUE_ENCODING: |
---|
| 269 | return (BDD_ONE(bddm)); |
---|
| 270 | case FALSE_ENCODING: |
---|
| 271 | return (BDD_ZERO(bddm)); |
---|
| 272 | case CONSTANT_ENCODING: |
---|
| 273 | value1=read(error, sizeof(long), fp); |
---|
| 274 | value2=read(error, sizeof(long), fp); |
---|
| 275 | if (*error) |
---|
| 276 | return ((bdd)0); |
---|
| 277 | if ((result=cmu_mtbdd_get_terminal(bddm, value1, value2))) |
---|
| 278 | return (result); |
---|
| 279 | *error=BDD_UNDUMP_OVERFLOW; |
---|
| 280 | return ((bdd)0); |
---|
| 281 | case POSVAR_ENCODING: |
---|
| 282 | case NEGVAR_ENCODING: |
---|
| 283 | i=read(error, index_size, fp); |
---|
| 284 | if (!*error && i >= number_vars) |
---|
| 285 | *error=BDD_UNDUMP_FORMAT; |
---|
| 286 | if (*error) |
---|
| 287 | return ((bdd)0); |
---|
| 288 | v=vars[i]; |
---|
| 289 | if (encoding == POSVAR_ENCODING) |
---|
| 290 | return (v); |
---|
| 291 | else |
---|
| 292 | return (BDD_NOT(v)); |
---|
| 293 | case POSNODE_ENCODING: |
---|
| 294 | case NEGNODE_ENCODING: |
---|
| 295 | node_number=read(error, node_number_size, fp); |
---|
| 296 | if (!*error && (node_number >= number_shared || !shared[node_number])) |
---|
| 297 | *error=BDD_UNDUMP_FORMAT; |
---|
| 298 | if (*error) |
---|
| 299 | return ((bdd)0); |
---|
| 300 | v=shared[node_number]; |
---|
| 301 | v=cmu_bdd_identity(bddm, v); |
---|
| 302 | if (encoding == POSNODE_ENCODING) |
---|
| 303 | return (v); |
---|
| 304 | else |
---|
| 305 | return (BDD_NOT(v)); |
---|
| 306 | case NODELABEL_ENCODING: |
---|
| 307 | node_number= *shared_so_far; |
---|
| 308 | ++*shared_so_far; |
---|
| 309 | v=cmu_bdd_undump_bdd_step(bddm, vars, fp, number_vars, shared, number_shared, |
---|
| 310 | shared_so_far, index_size, node_number_size, error); |
---|
| 311 | shared[node_number]=v; |
---|
| 312 | v=cmu_bdd_identity(bddm, v); |
---|
| 313 | return (v); |
---|
| 314 | default: |
---|
| 315 | *error=BDD_UNDUMP_FORMAT; |
---|
| 316 | return ((bdd)0); |
---|
| 317 | } |
---|
| 318 | } |
---|
| 319 | if (i >= number_vars) |
---|
| 320 | { |
---|
| 321 | *error=BDD_UNDUMP_FORMAT; |
---|
| 322 | return ((bdd)0); |
---|
| 323 | } |
---|
| 324 | temp1=cmu_bdd_undump_bdd_step(bddm, vars, fp, number_vars, shared, number_shared, |
---|
| 325 | shared_so_far, index_size, node_number_size, error); |
---|
| 326 | temp2=cmu_bdd_undump_bdd_step(bddm, vars, fp, number_vars, shared, number_shared, |
---|
| 327 | shared_so_far, index_size, node_number_size, error); |
---|
| 328 | if (*error) |
---|
| 329 | { |
---|
| 330 | cmu_bdd_free(bddm, temp1); |
---|
| 331 | return ((bdd)0); |
---|
| 332 | } |
---|
| 333 | result=cmu_bdd_ite(bddm, vars[i], temp1, temp2); |
---|
| 334 | cmu_bdd_free(bddm, temp1); |
---|
| 335 | cmu_bdd_free(bddm, temp2); |
---|
| 336 | if (!result) |
---|
| 337 | *error=BDD_UNDUMP_OVERFLOW; |
---|
| 338 | return (result); |
---|
| 339 | } |
---|
| 340 | |
---|
| 341 | |
---|
| 342 | bdd |
---|
| 343 | cmu_bdd_undump_bdd(cmu_bdd_manager bddm, bdd *vars, FILE *fp, int *error) |
---|
| 344 | { |
---|
| 345 | long i; |
---|
| 346 | bdd_index_type number_vars; |
---|
| 347 | long number_shared; |
---|
| 348 | int index_size; |
---|
| 349 | int node_number_size; |
---|
| 350 | bdd *shared; |
---|
| 351 | long shared_so_far; |
---|
| 352 | bdd v; |
---|
| 353 | bdd result; |
---|
| 354 | |
---|
| 355 | *error=0; |
---|
| 356 | for (i=0; vars[i]; ++i) |
---|
| 357 | if (cmu_bdd_type(bddm, vars[i]) != BDD_TYPE_POSVAR) |
---|
| 358 | { |
---|
| 359 | cmu_bdd_warning("cmu_bdd_undump_bdd: support is not all positive variables"); |
---|
| 360 | return ((bdd)0); |
---|
| 361 | } |
---|
| 362 | if (read(error, sizeof(long), fp) != MAGIC_COOKIE) |
---|
| 363 | { |
---|
| 364 | if (!*error) |
---|
| 365 | *error=BDD_UNDUMP_FORMAT; |
---|
| 366 | return ((bdd)0); |
---|
| 367 | } |
---|
| 368 | number_vars=read(error, sizeof(bdd_index_type), fp); |
---|
| 369 | if (*error) |
---|
| 370 | return ((bdd)0); |
---|
| 371 | if (number_vars != i) |
---|
| 372 | { |
---|
| 373 | *error=BDD_UNDUMP_FORMAT; |
---|
| 374 | return ((bdd)0); |
---|
| 375 | } |
---|
| 376 | number_shared=read(error, sizeof(long), fp); |
---|
| 377 | if (*error) |
---|
| 378 | return ((bdd)0); |
---|
| 379 | index_size=bytes_needed(number_vars+1); |
---|
| 380 | node_number_size=bytes_needed(number_shared); |
---|
| 381 | if (number_shared < 0) |
---|
| 382 | { |
---|
| 383 | *error=BDD_UNDUMP_FORMAT; |
---|
| 384 | return ((bdd)0); |
---|
| 385 | } |
---|
| 386 | shared=(bdd *)mem_get_block((SIZE_T)(number_shared*sizeof(bdd))); |
---|
| 387 | for (i=0; i < number_shared; ++i) |
---|
| 388 | shared[i]=0; |
---|
| 389 | shared_so_far=0; |
---|
| 390 | result=cmu_bdd_undump_bdd_step(bddm, vars, fp, number_vars, shared, number_shared, |
---|
| 391 | &shared_so_far, index_size, node_number_size, error); |
---|
| 392 | for (i=0; i < number_shared; ++i) |
---|
| 393 | if ((v=shared[i])) |
---|
| 394 | cmu_bdd_free(bddm, v); |
---|
| 395 | if (!*error && shared_so_far != number_shared) |
---|
| 396 | *error=BDD_UNDUMP_FORMAT; |
---|
| 397 | mem_free_block((pointer)shared); |
---|
| 398 | if (*error) |
---|
| 399 | { |
---|
| 400 | if (result) |
---|
| 401 | cmu_bdd_free(bddm, result); |
---|
| 402 | return ((bdd)0); |
---|
| 403 | } |
---|
| 404 | return (result); |
---|
| 405 | } |
---|