smatch_ranges.c

   1 /*
   2  * sparse/smatch_ranges.c
   3  *
   4  * Copyright (C) 2009 Dan Carpenter.
   5  *
   6  * Licensed under the Open Software License version 1.1
   7  *
   8  */
   9
  10 #include "parse.h"
  11 #include "smatch.h"
  12 #include "smatch_extra.h"
  13 #include "smatch_slist.h"
  14
  15 ALLOCATOR(data_info, "smatch extra data");
  16 ALLOCATOR(data_range, "data range");
  17 __DO_ALLOCATOR(struct data_range, sizeof(struct data_range), __alignof__(struct data_range),
  18                          "permanent ranges", perm_data_range);
  19
  20 static char *show_num(long long num)
  21 {
  22         static char buff[256];
  23
  24         if (num == whole_range.min) {
  25                 snprintf(buff, 255, "min");
  26         } else if (num == whole_range.max) {
  27                 snprintf(buff, 255, "max");
  28         } else if (num < 0) {
  29                 snprintf(buff, 255, "(%lld)", num);
  30         } else {
  31                 snprintf(buff, 255, "%lld", num);
  32         }
  33         buff[255] = '\0';
  34         return buff;
  35 }
  36
  37 char *show_ranges(struct range_list *list)
  38 {
  39         struct data_range *tmp;
  40         char full[256];
  41         int i = 0;
  42
  43         full[0] = '\0';
  44         full[255] = '\0';
  45         FOR_EACH_PTR(list, tmp) {
  46                 if (i++)
  47                         strncat(full, ",", 254 - strlen(full));
  48                 if (tmp->min == tmp->max) {
  49                         strncat(full, show_num(tmp->min), 254 - strlen(full));
  50                         continue;
  51                 }
  52                 strncat(full, show_num(tmp->min), 254 - strlen(full));
  53                 strncat(full, "-", 254 - strlen(full));
  54                 strncat(full, show_num(tmp->max), 254 - strlen(full));
  55         } END_FOR_EACH_PTR(tmp);
  56         return alloc_sname(full);
  57 }
  58
  59 static struct data_range range_zero = {
  60         .min = 0,
  61         .max = 0,
  62 };
  63
  64 static struct data_range range_one = {
  65         .min = 1,
  66         .max = 1,
  67 };
  68
  69 struct data_range *alloc_range(long long min, long long max)
  70 {
  71         struct data_range *ret;
  72
  73         if (min > max) {
  74                 printf("Error invalid range %lld to %lld\n", min, max);
  75         }
  76         if (min == whole_range.min && max == whole_range.max)
  77                 return &whole_range;
  78         if (min == 0 && max == 0)
  79                 return &range_zero;
  80         if (min == 1 && max == 1)
  81                 return &range_one;
  82         ret = __alloc_data_range(0);
  83         ret->min = min;
  84         ret->max = max;
  85         return ret;
  86 }
  87
  88 struct data_range *alloc_range_perm(long long min, long long max)
  89 {
  90         struct data_range *ret;
  91
  92         if (min > max) {
  93                 printf("Error invalid range %lld to %lld\n", min, max);
  94         }
  95         if (min == whole_range.min && max == whole_range.max)
  96                 return &whole_range;
  97         if (min == 0 && max == 0)
  98                 return &range_zero;
  99         if (min == 1 && max == 1)
 100                 return &range_one;
 101         ret = __alloc_perm_data_range(0);
 102         ret->min = min;
 103         ret->max = max;
 104         return ret;
 105 }
 106
 107 struct data_info *alloc_dinfo_range(long long min, long long max)
 108 {
 109         struct data_info *ret;
 110
 111         ret = __alloc_data_info(0);
 112         ret->type = DATA_RANGE;
 113         ret->value_ranges = NULL;
 114         add_range(&ret->value_ranges, min, max);
 115         return ret;
 116 }
 117
 118 struct data_info *alloc_dinfo_range_list(struct range_list *rl)
 119 {
 120         struct data_info *ret;
 121
 122         ret = __alloc_data_info(0);
 123         ret->type = DATA_RANGE;
 124         ret->value_ranges = rl;
 125         return ret;
 126 }
 127
 128 void add_range(struct range_list **list, long long min, long long max)
 129 {
 130         struct data_range *tmp = NULL;
 131         struct data_range *new;
 132         int check_next = 0;
 133
 134         FOR_EACH_PTR(*list, tmp) {
 135                 if (check_next) {
 136                         /* Sometimes we overlap with more than one range
 137                            so we have to delete or modify the next range. */
 138
 139                         /* Doesn't overlap with the next one. */
 140                         if (max < tmp->min)
 141                                 return;
 142                         /* Partially overlaps with the next one. */
 143                         if (max < tmp->max) {
 144                                 tmp->min = max + 1;
 145                                 return;
 146                         }
 147                         /* Completely overlaps with the next one. */
 148                         if (max > tmp->max) {
 149                                 DELETE_CURRENT_PTR(tmp);
 150                                 continue;
 151                         }
 152                 }
 153                 if (max != whole_range.max && max + 1 == tmp->min) {
 154                         /* join 2 ranges into a big range */
 155                         new = alloc_range(min, tmp->max);
 156                         REPLACE_CURRENT_PTR(tmp, new);
 157                         return;
 158                 }
 159                 if (max < tmp->min) {  /* new range entirely below */
 160                         new = alloc_range(min, max);
 161                         INSERT_CURRENT(new, tmp);
 162                         return;
 163                 }
 164                 if (min < tmp->min) { /* new range partially below */
 165                         if (max < tmp->max)
 166                                 max = tmp->max;
 167                         else
 168                                 check_next = 1;
 169                         new = alloc_range(min, max);
 170                         REPLACE_CURRENT_PTR(tmp, new);
 171                         if (!check_next)
 172                                 return;
 173                 }
 174                 if (max <= tmp->max) /* new range already included */
 175                         return;
 176                 if (min <= tmp->max) { /* new range partially above */
 177                         min = tmp->min;
 178                         new = alloc_range(min, max);
 179                         REPLACE_CURRENT_PTR(tmp, new);
 180                         check_next = 1;
 181                 }
 182                 if (min != whole_range.min && min - 1 == tmp->max) {
 183                         /* join 2 ranges into a big range */
 184                         new = alloc_range(tmp->min, max);
 185                         REPLACE_CURRENT_PTR(tmp, new);
 186                         check_next = 1;
 187                 }
 188         } END_FOR_EACH_PTR(tmp);
 189         if (check_next)
 190                 return;
 191         new = alloc_range(min, max);
 192         add_ptr_list(list, new);
 193 }
 194
 195 struct range_list *clone_range_list(struct range_list *list)
 196 {
 197         struct data_range *tmp;
 198         struct range_list *ret = NULL;
 199
 200         FOR_EACH_PTR(list, tmp) {
 201                 add_ptr_list(&ret, tmp);
 202         } END_FOR_EACH_PTR(tmp);
 203         return ret;
 204 }
 205
 206 struct range_list *range_list_union(struct range_list *one, struct range_list *two)
 207 {
 208         struct data_range *tmp;
 209         struct range_list *ret = NULL;
 210
 211         if (!one || !two)  /*having nothing in a list means everything is in */
 212                 return NULL;
 213
 214         FOR_EACH_PTR(one, tmp) {
 215                 add_range(&ret, tmp->min, tmp->max);
 216         } END_FOR_EACH_PTR(tmp);
 217         FOR_EACH_PTR(two, tmp) {
 218                 add_range(&ret, tmp->min, tmp->max);
 219         } END_FOR_EACH_PTR(tmp);
 220         return ret;
 221 }
 222
 223 struct range_list *remove_range(struct range_list *list, long long min, long long max)
 224 {
 225         struct data_range *tmp;
 226         struct range_list *ret = NULL;
 227
 228         FOR_EACH_PTR(list, tmp) {
 229                 if (tmp->max < min) {
 230                         add_range(&ret, tmp->min, tmp->max);
 231                         continue;
 232                 }
 233                 if (tmp->min > max) {
 234                         add_range(&ret, tmp->min, tmp->max);
 235                         continue;
 236                 }
 237                 if (tmp->min >= min && tmp->max <= max)
 238                         continue;
 239                 if (tmp->min >= min) {
 240                         add_range(&ret, max + 1, tmp->max);
 241                 } else if (tmp->max <= max) {
 242                         add_range(&ret, tmp->min, min - 1);
 243                 } else {
 244                         add_range(&ret, tmp->min, min - 1);
 245                         add_range(&ret, max + 1, tmp->max);
 246                 }
 247         } END_FOR_EACH_PTR(tmp);
 248         return ret;
 249 }
 250
 251 long long get_dinfo_min(struct data_info *dinfo)
 252 {
 253         struct data_range *drange;
 254
 255         if (!dinfo || !dinfo->value_ranges)
 256                 return whole_range.min;
 257         drange = first_ptr_list((struct ptr_list *)dinfo->value_ranges);
 258         return drange->min;
 259 }
 260
 261 long long get_dinfo_max(struct data_info *dinfo)
 262 {
 263         struct data_range *drange;
 264
 265         if (!dinfo || !dinfo->value_ranges)
 266                 return whole_range.max;
 267         drange = first_ptr_list((struct ptr_list *)dinfo->value_ranges);
 268         return drange->max;
 269 }
 270
 271 /*
 272  * if it can be only one and only value return 1, else return 0
 273  */
 274 int get_single_value_from_range(struct data_info *dinfo, long long *val)
 275 {
 276         struct data_range *tmp;
 277         int count = 0;
 278
 279         if (dinfo->type != DATA_RANGE)
 280                 return 0;
 281
 282         FOR_EACH_PTR(dinfo->value_ranges, tmp) {
 283                 if (!count++) {
 284                         if (tmp->min != tmp->max)
 285                                 return 0;
 286                         *val = tmp->min;
 287                 } else {
 288                         return 0;
 289                 }
 290         } END_FOR_EACH_PTR(tmp);
 291         return 1;
 292 }
 293
 294 int true_comparison_range(struct data_range *left, int comparison, struct data_range *right)
 295 {
 296         switch(comparison){
 297         case '<':
 298         case SPECIAL_UNSIGNED_LT:
 299                 if (left->min < right->max)
 300                         return 1;
 301                 return 0;
 302         case SPECIAL_UNSIGNED_LTE:
 303         case SPECIAL_LTE:
 304                 if (left->min <= right->max)
 305                         return 1;
 306                 return 0;
 307         case SPECIAL_EQUAL:
 308                 if (left->max < right->min)
 309                         return 0;
 310                 if (left->min > right->max)
 311                         return 0;
 312                 return 1;
 313         case SPECIAL_UNSIGNED_GTE:
 314         case SPECIAL_GTE:
 315                 if (left->max >= right->min)
 316                         return 1;
 317                 return 0;
 318         case '>':
 319         case SPECIAL_UNSIGNED_GT:
 320                 if (left->max > right->min)
 321                         return 1;
 322                 return 0;
 323         case SPECIAL_NOTEQUAL:
 324                 if (left->min != left->max)
 325                         return 1;
 326                 if (right->min != right->max)
 327                         return 1;
 328                 if (left->min != right->min)
 329                         return 1;
 330                 return 0;
 331         default:
 332                 sm_msg("unhandled comparison %d\n", comparison);
 333                 return 0;
 334         }
 335         return 0;
 336 }
 337
 338 int true_comparison_range_lr(int comparison, struct data_range *var, struct data_range *val, int left)
 339 {
 340         if (left)
 341                 return true_comparison_range(var, comparison, val);
 342         else
 343                 return true_comparison_range(val, comparison, var);
 344 }
 345
 346 static int false_comparison_range(struct data_range *left, int comparison, struct data_range *right)
 347 {
 348         switch(comparison){
 349         case '<':
 350         case SPECIAL_UNSIGNED_LT:
 351                 if (left->max >= right->min)
 352                         return 1;
 353                 return 0;
 354         case SPECIAL_UNSIGNED_LTE:
 355         case SPECIAL_LTE:
 356                 if (left->max > right->min)
 357                         return 1;
 358                 return 0;
 359         case SPECIAL_EQUAL:
 360                 if (left->min != left->max)
 361                         return 1;
 362                 if (right->min != right->max)
 363                         return 1;
 364                 if (left->min != right->min)
 365                         return 1;
 366                 return 0;
 367         case SPECIAL_UNSIGNED_GTE:
 368         case SPECIAL_GTE:
 369                 if (left->min < right->max)
 370                         return 1;
 371                 return 0;
 372         case '>':
 373         case SPECIAL_UNSIGNED_GT:
 374                 if (left->min <= right->max)
 375                         return 1;
 376                 return 0;
 377         case SPECIAL_NOTEQUAL:
 378                 if (left->max < right->min)
 379                         return 0;
 380                 if (left->min > right->max)
 381                         return 0;
 382                 return 1;
 383         default:
 384                 sm_msg("unhandled comparison %d\n", comparison);
 385                 return 0;
 386         }
 387         return 0;
 388 }
 389
 390 int false_comparison_range_lr(int comparison, struct data_range *var, struct data_range *val, int left)
 391 {
 392         if (left)
 393                 return false_comparison_range(var, comparison, val);
 394         else
 395                 return false_comparison_range(val, comparison, var);
 396 }
 397
 398 int possibly_true(int comparison, struct data_info *dinfo, int num, int left)
 399 {
 400         struct data_range *tmp;
 401         struct data_range drange;
 402
 403         drange.min = num;
 404         drange.max = num;
 405
 406         FOR_EACH_PTR(dinfo->value_ranges, tmp) {
 407                 if (true_comparison_range_lr(comparison, tmp, &drange, left))
 408                         return 1;
 409         } END_FOR_EACH_PTR(tmp);
 410         return 0;
 411 }
 412
 413 int possibly_false(int comparison, struct data_info *dinfo, int num, int left)
 414 {
 415         struct data_range *tmp;
 416         struct data_range drange;
 417
 418         drange.min = num;
 419         drange.max = num;
 420
 421         FOR_EACH_PTR(dinfo->value_ranges, tmp) {
 422                 if (false_comparison_range_lr(comparison, tmp, &drange, left))
 423                         return 1;
 424         } END_FOR_EACH_PTR(tmp);
 425         return 0;
 426 }
 427
 428 int possibly_true_range_list(int comparison, struct data_info *dinfo, struct range_list *values, int left)
 429 {
 430         struct data_range *tmp, *tmp2;
 431
 432         FOR_EACH_PTR(dinfo->value_ranges, tmp) {
 433                 FOR_EACH_PTR(values, tmp2) {
 434                         if (true_comparison_range_lr(comparison, tmp, tmp2, left))
 435                                 return 1;
 436                 } END_FOR_EACH_PTR(tmp2);
 437         } END_FOR_EACH_PTR(tmp);
 438         return 0;
 439 }
 440
 441 int possibly_false_range_list(int comparison, struct data_info *dinfo, struct range_list *values, int left)
 442 {
 443         struct data_range *tmp, *tmp2;
 444
 445         FOR_EACH_PTR(dinfo->value_ranges, tmp) {
 446                 FOR_EACH_PTR(values, tmp2) {
 447                         if (false_comparison_range_lr(comparison, tmp, tmp2, left))
 448                                 return 1;
 449                 } END_FOR_EACH_PTR(tmp2);
 450         } END_FOR_EACH_PTR(tmp);
 451         return 0;
 452 }
 453
 454 void tack_on(struct range_list **list, struct data_range *drange)
 455 {
 456         add_ptr_list(list, drange);
 457 }
 458
 459 int in_list_exact(struct range_list *list, struct data_range *drange)
 460 {
 461         struct data_range *tmp;
 462
 463         FOR_EACH_PTR(list, tmp) {
 464                 if (tmp->min == drange->min && tmp->max == drange->max)
 465                         return 1;
 466         } END_FOR_EACH_PTR(tmp);
 467         return 0;
 468
 469 }
 470
 471 void push_range_list(struct range_list_stack **rl_stack, struct range_list *rl)
 472 {
 473         add_ptr_list(rl_stack, rl);
 474 }
 475
 476 struct range_list *pop_range_list(struct range_list_stack **rl_stack)
 477 {
 478         struct range_list *rl;
 479
 480         rl = last_ptr_list((struct ptr_list *)*rl_stack);
 481         delete_ptr_list_last((struct ptr_list **)rl_stack);
 482         return rl;
 483 }
 484
 485 struct range_list *top_range_list(struct range_list_stack *rl_stack)
 486 {
 487         struct range_list *rl;
 488
 489         rl = last_ptr_list((struct ptr_list *)rl_stack);
 490         return rl;
 491 }
 492
 493 void filter_top_range_list(struct range_list_stack **rl_stack, long long num)
 494 {
 495         struct range_list *rl;
 496
 497         rl = pop_range_list(rl_stack);
 498         rl = remove_range(rl, num, num);
 499         push_range_list(rl_stack, rl);
 500 }
 501
 502 static void free_single_dinfo(struct data_info *dinfo)
 503 {
 504         if (dinfo->type == DATA_RANGE)
 505                 __free_ptr_list((struct ptr_list **)&dinfo->value_ranges);
 506 }
 507
 508 static void free_dinfos(struct allocation_blob *blob)
 509 {
 510         unsigned int size = sizeof(struct data_info);
 511         unsigned int offset = 0;
 512
 513         while (offset < blob->offset) {
 514                 free_single_dinfo((struct data_info *)(blob->data + offset));
 515                 offset += size;
 516         }
 517 }
 518
 519 void free_data_info_allocs(void)
 520 {
 521         struct allocator_struct *desc = &data_info_allocator;
 522         struct allocation_blob *blob = desc->blobs;
 523
 524         desc->blobs = NULL;
 525         desc->allocations = 0;
 526         desc->total_bytes = 0;
 527         desc->useful_bytes = 0;
 528         desc->freelist = NULL;
 529         while (blob) {
 530                 struct allocation_blob *next = blob->next;
 531                 free_dinfos(blob);
 532                 blob_free(blob, desc->chunking);
 533                 blob = next;
 534         }
 535         clear_data_range_alloc();
 536 }
 537