smatch_flow.c

   1 /*
   2  * Copyright (C) 2006,2008 Dan Carpenter.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
  16  */
  17
  18 #define _GNU_SOURCE 1
  19 #include <unistd.h>
  20 #include <stdio.h>
  21 #include "token.h"
  22 #include "scope.h"
  23 #include "smatch.h"
  24 #include "smatch_expression_stacks.h"
  25 #include "smatch_extra.h"
  26 #include "smatch_slist.h"
  27
  28 int __in_fake_assign;
  29 int __in_fake_struct_assign;
  30 static int in_fake_env;
  31 int final_pass;
  32 int __inline_call;
  33 struct expression  *__inline_fn;
  34
  35 static int __smatch_lineno = 0;
  36
  37 static char *base_file;
  38 static const char *filename;
  39 static char *pathname;
  40 static char *full_filename;
  41 static char *cur_func;
  42 static unsigned int loop_count;
  43 static int last_goto_statement_handled;
  44 int __expr_stmt_count;
  45 int __in_function_def;
  46 static struct expression_list *switch_expr_stack = NULL;
  47 static struct expression_list *post_op_stack = NULL;
  48
  49 static struct ptr_list *backup;
  50
  51 struct expression_list *big_expression_stack;
  52 struct statement_list *big_statement_stack;
  53 struct statement *__prev_stmt;
  54 struct statement *__cur_stmt;
  55 struct statement *__next_stmt;
  56 int __in_pre_condition = 0;
  57 int __bail_on_rest_of_function = 0;
  58 static struct timeval fn_start_time;
  59 char *get_function(void) { return cur_func; }
  60 int get_lineno(void) { return __smatch_lineno; }
  61 int inside_loop(void) { return !!loop_count; }
  62 int definitely_inside_loop(void) { return !!(loop_count & ~0x08000000); }
  63 struct expression *get_switch_expr(void) { return top_expression(switch_expr_stack); }
  64 int in_expression_statement(void) { return !!__expr_stmt_count; }
  65
  66 static void split_symlist(struct symbol_list *sym_list);
  67 static void split_declaration(struct symbol_list *sym_list);
  68 static void split_expr_list(struct expression_list *expr_list, struct expression *parent);
  69 static void add_inline_function(struct symbol *sym);
  70 static void parse_inline(struct expression *expr);
  71
  72 int option_assume_loops = 0;
  73 int option_two_passes = 0;
  74 struct symbol *cur_func_sym = NULL;
  75 struct stree *global_states;
  76
  77 long long valid_ptr_min = 4096;
  78 long long valid_ptr_max = 2117777777;
  79 sval_t valid_ptr_min_sval = {
  80         .type = &ptr_ctype,
  81         {.value = 4096},
  82 };
  83 sval_t valid_ptr_max_sval = {
  84         .type = &ptr_ctype,
  85         {.value = LONG_MAX - 100000},
  86 };
  87
  88 static void set_valid_ptr_max(void)
  89 {
  90         if (type_bits(&ptr_ctype) == 32)
  91                 valid_ptr_max = 2117777777;
  92         else if (type_bits(&ptr_ctype) == 64)
  93                 valid_ptr_max = 2117777777777777777LL;
  94
  95         valid_ptr_max_sval.value = valid_ptr_max;
  96 }
  97
  98 int outside_of_function(void)
  99 {
 100         return cur_func_sym == NULL;
 101 }
 102
 103 const char *get_filename(void)
 104 {
 105         if (option_info)
 106                 return base_file;
 107         if (option_full_path)
 108                 return full_filename;
 109         return filename;
 110 }
 111
 112 const char *get_base_file(void)
 113 {
 114         return base_file;
 115 }
 116
 117 static void set_position(struct position pos)
 118 {
 119         int len;
 120         static int prev_stream = -1;
 121
 122         if (in_fake_env)
 123                 return;
 124
 125         if (pos.stream == 0 && pos.line == 0)
 126                 return;
 127
 128         __smatch_lineno = pos.line;
 129
 130         if (pos.stream == prev_stream)
 131                 return;
 132
 133         filename = stream_name(pos.stream);
 134
 135         free(full_filename);
 136         pathname = getcwd(NULL, 0);
 137         if (pathname) {
 138                 len = strlen(pathname) + 1 + strlen(filename) + 1;
 139                 full_filename = malloc(len);
 140                 snprintf(full_filename, len, "%s/%s", pathname, filename);
 141         } else {
 142                 full_filename = alloc_string(filename);
 143         }
 144         free(pathname);
 145 }
 146
 147 int is_assigned_call(struct expression *expr)
 148 {
 149         struct expression *parent = expr_get_parent_expr(expr);
 150
 151         if (parent &&
 152             parent->type == EXPR_ASSIGNMENT &&
 153             parent->op == '=' &&
 154             strip_expr(parent->right) == expr)
 155                 return 1;
 156
 157         return 0;
 158 }
 159
 160 static int is_inline_func(struct expression *expr)
 161 {
 162         if (expr->type != EXPR_SYMBOL || !expr->symbol)
 163                 return 0;
 164         if (expr->symbol->ctype.modifiers & MOD_INLINE)
 165                 return 1;
 166         return 0;
 167 }
 168
 169 static int is_noreturn_func(struct expression *expr)
 170 {
 171         if (expr->type != EXPR_SYMBOL || !expr->symbol)
 172                 return 0;
 173         if (expr->symbol->ctype.modifiers & MOD_NORETURN)
 174                 return 1;
 175         return 0;
 176 }
 177
 178 int inlinable(struct expression *expr)
 179 {
 180         struct symbol *sym;
 181         struct statement *last_stmt = NULL;
 182
 183         if (__inline_fn)  /* don't nest */
 184                 return 0;
 185
 186         if (expr->type != EXPR_SYMBOL || !expr->symbol)
 187                 return 0;
 188         if (is_no_inline_function(expr->symbol->ident->name))
 189                 return 0;
 190         sym = get_base_type(expr->symbol);
 191         if (sym->stmt && sym->stmt->type == STMT_COMPOUND) {
 192                 if (ptr_list_size((struct ptr_list *)sym->stmt->stmts) > 10)
 193                         return 0;
 194                 if (sym->stmt->type != STMT_COMPOUND)
 195                         return 0;
 196                 last_stmt = last_ptr_list((struct ptr_list *)sym->stmt->stmts);
 197         }
 198         if (sym->inline_stmt && sym->inline_stmt->type == STMT_COMPOUND) {
 199                 if (ptr_list_size((struct ptr_list *)sym->inline_stmt->stmts) > 10)
 200                         return 0;
 201                 if (sym->inline_stmt->type != STMT_COMPOUND)
 202                         return 0;
 203                 last_stmt = last_ptr_list((struct ptr_list *)sym->inline_stmt->stmts);
 204         }
 205
 206         if (!last_stmt)
 207                 return 0;
 208
 209         /* the magic numbers in this function are pulled out of my bum. */
 210         if (last_stmt->pos.line > sym->pos.line + 20)
 211                 return 0;
 212
 213         return 1;
 214 }
 215
 216 void __process_post_op_stack(void)
 217 {
 218         struct expression *expr;
 219
 220         FOR_EACH_PTR(post_op_stack, expr) {
 221                 __pass_to_client(expr, OP_HOOK);
 222         } END_FOR_EACH_PTR(expr);
 223
 224         __free_ptr_list((struct ptr_list **)&post_op_stack);
 225 }
 226
 227 static int handle_comma_assigns(struct expression *expr)
 228 {
 229         struct expression *right;
 230         struct expression *assign;
 231
 232         right = strip_expr(expr->right);
 233         if (right->type != EXPR_COMMA)
 234                 return 0;
 235
 236         __split_expr(right->left);
 237         __process_post_op_stack();
 238
 239         assign = assign_expression(expr->left, '=', right->right);
 240         __split_expr(assign);
 241
 242         return 1;
 243 }
 244
 245 /* This is to handle *p++ = foo; assignments */
 246 static int handle_postop_assigns(struct expression *expr)
 247 {
 248         struct expression *left, *fake_left;
 249         struct expression *assign;
 250
 251         left = strip_expr(expr->left);
 252         if (left->type != EXPR_PREOP || left->op != '*')
 253                 return 0;
 254         left = strip_expr(left->unop);
 255         if (left->type != EXPR_POSTOP)
 256                 return 0;
 257
 258         fake_left = deref_expression(strip_expr(left->unop));
 259         assign = assign_expression(fake_left, '=', expr->right);
 260
 261         __split_expr(assign);
 262         __split_expr(expr->left);
 263
 264         return 1;
 265 }
 266
 267 static int prev_expression_is_getting_address(struct expression *expr)
 268 {
 269         struct expression *parent;
 270
 271         do {
 272                 parent = expr_get_parent_expr(expr);
 273
 274                 if (!parent)
 275                         return 0;
 276                 if (parent->type == EXPR_PREOP && parent->op == '&')
 277                         return 1;
 278                 if (parent->type == EXPR_PREOP && parent->op == '(')
 279                         goto next;
 280                 if (parent->type == EXPR_DEREF && parent->op == '.')
 281                         goto next;
 282
 283                 return 0;
 284 next:
 285                 expr = parent;
 286         } while (1);
 287 }
 288
 289 static int handle__builtin_choose_expr(struct expression *expr)
 290 {
 291         struct expression *const_expr, *expr1, *expr2;
 292         sval_t sval;
 293
 294         if (!sym_name_is("__builtin_choose_expr", expr->fn))
 295                 return 0;
 296
 297         const_expr = get_argument_from_call_expr(expr->args, 0);
 298         expr1 = get_argument_from_call_expr(expr->args, 1);
 299         expr2 = get_argument_from_call_expr(expr->args, 2);
 300
 301         if (!get_value(const_expr, &sval) || !expr1 || !expr2)
 302                 return 0;
 303         if (sval.value)
 304                 __split_expr(expr1);
 305         else
 306                 __split_expr(expr2);
 307         return 1;
 308 }
 309
 310 void __split_expr(struct expression *expr)
 311 {
 312         if (!expr)
 313                 return;
 314
 315         // sm_msg(" Debug expr_type %d %s", expr->type, show_special(expr->op));
 316
 317         if (__in_fake_assign && expr->type != EXPR_ASSIGNMENT)
 318                 return;
 319         if (__in_fake_assign >= 4)  /* don't allow too much nesting */
 320                 return;
 321
 322         push_expression(&big_expression_stack, expr);
 323         set_position(expr->pos);
 324         __pass_to_client(expr, EXPR_HOOK);
 325
 326         switch (expr->type) {
 327         case EXPR_PREOP:
 328                 expr_set_parent_expr(expr->unop, expr);
 329
 330                 if (expr->op == '*' &&
 331                     !prev_expression_is_getting_address(expr))
 332                         __pass_to_client(expr, DEREF_HOOK);
 333                 __split_expr(expr->unop);
 334                 __pass_to_client(expr, OP_HOOK);
 335                 break;
 336         case EXPR_POSTOP:
 337                 expr_set_parent_expr(expr->unop, expr);
 338
 339                 __split_expr(expr->unop);
 340                 push_expression(&post_op_stack, expr);
 341                 break;
 342         case EXPR_STATEMENT:
 343                 __expr_stmt_count++;
 344                 if (expr->statement && !expr->statement) {
 345                         stmt_set_parent_stmt(expr->statement,
 346                                         last_ptr_list((struct ptr_list *)big_statement_stack));
 347                 }
 348                 __split_stmt(expr->statement);
 349                 __expr_stmt_count--;
 350                 break;
 351         case EXPR_LOGICAL:
 352         case EXPR_COMPARE:
 353                 expr_set_parent_expr(expr->left, expr);
 354                 expr_set_parent_expr(expr->right, expr);
 355
 356                 __pass_to_client(expr, LOGIC_HOOK);
 357                 __handle_logic(expr);
 358                 break;
 359         case EXPR_BINOP:
 360                 expr_set_parent_expr(expr->left, expr);
 361                 expr_set_parent_expr(expr->right, expr);
 362
 363                 __pass_to_client(expr, BINOP_HOOK);
 364         case EXPR_COMMA:
 365                 expr_set_parent_expr(expr->left, expr);
 366                 expr_set_parent_expr(expr->right, expr);
 367
 368                 __split_expr(expr->left);
 369                 __process_post_op_stack();
 370                 __split_expr(expr->right);
 371                 break;
 372         case EXPR_ASSIGNMENT: {
 373                 struct expression *right;
 374
 375                 expr_set_parent_expr(expr->left, expr);
 376                 expr_set_parent_expr(expr->right, expr);
 377
 378                 right = strip_expr(expr->right);
 379                 if (!right)
 380                         break;
 381
 382                 __pass_to_client(expr, RAW_ASSIGNMENT_HOOK);
 383
 384                 /* foo = !bar() */
 385                 if (__handle_condition_assigns(expr))
 386                         break;
 387                 /* foo = (x < 5 ? foo : 5); */
 388                 if (__handle_select_assigns(expr))
 389                         break;
 390                 /* foo = ({frob(); frob(); frob(); 1;}) */
 391                 if (__handle_expr_statement_assigns(expr))
 392                         break;
 393                 /* foo = (3, 4); */
 394                 if (handle_comma_assigns(expr))
 395                         break;
 396                 if (handle_postop_assigns(expr))
 397                         break;
 398
 399                 __split_expr(expr->right);
 400                 if (outside_of_function())
 401                         __pass_to_client(expr, GLOBAL_ASSIGNMENT_HOOK);
 402                 else
 403                         __pass_to_client(expr, ASSIGNMENT_HOOK);
 404
 405                 __fake_struct_member_assignments(expr);
 406
 407                 if (expr->op == '=' && right->type == EXPR_CALL)
 408                         __pass_to_client(expr, CALL_ASSIGNMENT_HOOK);
 409
 410                 if (get_macro_name(right->pos) &&
 411                     get_macro_name(expr->pos) != get_macro_name(right->pos))
 412                         __pass_to_client(expr, MACRO_ASSIGNMENT_HOOK);
 413
 414                 __pass_to_client(expr, ASSIGNMENT_HOOK_AFTER);
 415
 416                 __split_expr(expr->left);
 417                 break;
 418         }
 419         case EXPR_DEREF:
 420                 expr_set_parent_expr(expr->deref, expr);
 421
 422                 __pass_to_client(expr, DEREF_HOOK);
 423                 __split_expr(expr->deref);
 424                 break;
 425         case EXPR_SLICE:
 426                 expr_set_parent_expr(expr->base, expr);
 427
 428                 __split_expr(expr->base);
 429                 break;
 430         case EXPR_CAST:
 431         case EXPR_FORCE_CAST:
 432                 expr_set_parent_expr(expr->cast_expression, expr);
 433
 434                 __pass_to_client(expr, CAST_HOOK);
 435                 __split_expr(expr->cast_expression);
 436                 break;
 437         case EXPR_SIZEOF:
 438                 if (expr->cast_expression)
 439                         __pass_to_client(strip_parens(expr->cast_expression),
 440                                          SIZEOF_HOOK);
 441                 break;
 442         case EXPR_OFFSETOF:
 443         case EXPR_ALIGNOF:
 444                 evaluate_expression(expr);
 445                 break;
 446         case EXPR_CONDITIONAL:
 447         case EXPR_SELECT:
 448                 expr_set_parent_expr(expr->conditional, expr);
 449                 expr_set_parent_expr(expr->cond_true, expr);
 450                 expr_set_parent_expr(expr->cond_false, expr);
 451
 452                 if (known_condition_true(expr->conditional)) {
 453                         __split_expr(expr->cond_true);
 454                         break;
 455                 }
 456                 if (known_condition_false(expr->conditional)) {
 457                         __split_expr(expr->cond_false);
 458                         break;
 459                 }
 460                 __pass_to_client(expr, SELECT_HOOK);
 461                 __split_whole_condition(expr->conditional);
 462                 __split_expr(expr->cond_true);
 463                 __push_true_states();
 464                 __use_false_states();
 465                 __split_expr(expr->cond_false);
 466                 __merge_true_states();
 467                 break;
 468         case EXPR_CALL:
 469                 expr_set_parent_expr(expr->fn, expr);
 470
 471                 if (sym_name_is("__builtin_constant_p", expr->fn))
 472                         break;
 473                 if (handle__builtin_choose_expr(expr))
 474                         break;
 475                 split_expr_list(expr->args, expr);
 476                 __split_expr(expr->fn);
 477                 if (is_inline_func(expr->fn))
 478                         add_inline_function(expr->fn->symbol);
 479                 if (inlinable(expr->fn))
 480                         __inline_call = 1;
 481                 __process_post_op_stack();
 482                 __pass_to_client(expr, FUNCTION_CALL_HOOK_BEFORE);
 483                 __pass_to_client(expr, FUNCTION_CALL_HOOK);
 484                 __inline_call = 0;
 485                 if (inlinable(expr->fn)) {
 486                         parse_inline(expr);
 487                 }
 488                 __pass_to_client(expr, CALL_HOOK_AFTER_INLINE);
 489                 if (is_noreturn_func(expr->fn))
 490                         nullify_path();
 491                 break;
 492         case EXPR_INITIALIZER:
 493                 split_expr_list(expr->expr_list, expr);
 494                 break;
 495         case EXPR_IDENTIFIER:
 496                 expr_set_parent_expr(expr->ident_expression, expr);
 497                 __split_expr(expr->ident_expression);
 498                 break;
 499         case EXPR_INDEX:
 500                 expr_set_parent_expr(expr->idx_expression, expr);
 501                 __split_expr(expr->idx_expression);
 502                 break;
 503         case EXPR_POS:
 504                 expr_set_parent_expr(expr->init_expr, expr);
 505                 __split_expr(expr->init_expr);
 506                 break;
 507         case EXPR_SYMBOL:
 508                 __pass_to_client(expr, SYM_HOOK);
 509                 break;
 510         case EXPR_STRING:
 511                 __pass_to_client(expr, STRING_HOOK);
 512                 break;
 513         default:
 514                 break;
 515         };
 516         pop_expression(&big_expression_stack);
 517 }
 518
 519 static int is_forever_loop(struct statement *stmt)
 520 {
 521         struct expression *expr;
 522         sval_t sval;
 523
 524         expr = strip_expr(stmt->iterator_pre_condition);
 525         if (!expr)
 526                 expr = stmt->iterator_post_condition;
 527         if (!expr) {
 528                 /* this is a for(;;) loop... */
 529                 return 1;
 530         }
 531
 532         if (get_value(expr, &sval) && sval.value != 0)
 533                 return 1;
 534
 535         return 0;
 536 }
 537
 538 static int loop_num;
 539 static char *get_loop_name(int num)
 540 {
 541         char buf[256];
 542
 543         snprintf(buf, 255, "-loop%d", num);
 544         buf[255] = '\0';
 545         return alloc_sname(buf);
 546 }
 547
 548 /*
 549  * Pre Loops are while and for loops.
 550  */
 551 static void handle_pre_loop(struct statement *stmt)
 552 {
 553         int once_through; /* we go through the loop at least once */
 554         struct sm_state *extra_sm = NULL;
 555         int unchanged = 0;
 556         char *loop_name;
 557         struct stree *stree = NULL;
 558         struct sm_state *sm = NULL;
 559
 560         loop_name = get_loop_name(loop_num);
 561         loop_num++;
 562
 563         __split_stmt(stmt->iterator_pre_statement);
 564         __prev_stmt = stmt->iterator_pre_statement;
 565
 566         once_through = implied_condition_true(stmt->iterator_pre_condition);
 567
 568         loop_count++;
 569         __push_continues();
 570         __push_breaks();
 571
 572         __merge_gotos(loop_name, NULL);
 573
 574         extra_sm = __extra_handle_canonical_loops(stmt, &stree);
 575         __in_pre_condition++;
 576         __pass_to_client(stmt, PRELOOP_HOOK);
 577         __split_whole_condition(stmt->iterator_pre_condition);
 578         __in_pre_condition--;
 579         FOR_EACH_SM(stree, sm) {
 580                 set_state(sm->owner, sm->name, sm->sym, sm->state);
 581         } END_FOR_EACH_SM(sm);
 582         free_stree(&stree);
 583         if (extra_sm)
 584                 extra_sm = get_sm_state(extra_sm->owner, extra_sm->name, extra_sm->sym);
 585
 586         if (option_assume_loops)
 587                 once_through = 1;
 588
 589         __split_stmt(stmt->iterator_statement);
 590         if (is_forever_loop(stmt)) {
 591                 __merge_continues();
 592                 __save_gotos(loop_name, NULL);
 593
 594                 __push_fake_cur_stree();
 595                 __split_stmt(stmt->iterator_post_statement);
 596                 stree = __pop_fake_cur_stree();
 597
 598                 __discard_false_states();
 599                 __use_breaks();
 600
 601                 if (!__path_is_null())
 602                         __merge_stree_into_cur(stree);
 603                 free_stree(&stree);
 604         } else {
 605                 __merge_continues();
 606                 unchanged = __iterator_unchanged(extra_sm);
 607                 __split_stmt(stmt->iterator_post_statement);
 608                 __prev_stmt = stmt->iterator_post_statement;
 609                 __cur_stmt = stmt;
 610
 611                 __save_gotos(loop_name, NULL);
 612                 __in_pre_condition++;
 613                 __split_whole_condition(stmt->iterator_pre_condition);
 614                 __in_pre_condition--;
 615                 nullify_path();
 616                 __merge_false_states();
 617                 if (once_through)
 618                         __discard_false_states();
 619                 else
 620                         __merge_false_states();
 621
 622                 if (extra_sm && unchanged)
 623                         __extra_pre_loop_hook_after(extra_sm,
 624                                                 stmt->iterator_post_statement,
 625                                                 stmt->iterator_pre_condition);
 626                 __merge_breaks();
 627         }
 628         loop_count--;
 629 }
 630
 631 /*
 632  * Post loops are do {} while();
 633  */
 634 static void handle_post_loop(struct statement *stmt)
 635 {
 636         char *loop_name;
 637
 638         loop_name = get_loop_name(loop_num);
 639         loop_num++;
 640         loop_count++;
 641
 642         __push_continues();
 643         __push_breaks();
 644         __merge_gotos(loop_name, NULL);
 645         __split_stmt(stmt->iterator_statement);
 646         __merge_continues();
 647         if (!is_zero(stmt->iterator_post_condition))
 648                 __save_gotos(loop_name, NULL);
 649
 650         if (is_forever_loop(stmt)) {
 651                 __use_breaks();
 652         } else {
 653                 __split_whole_condition(stmt->iterator_post_condition);
 654                 __use_false_states();
 655                 __merge_breaks();
 656         }
 657         loop_count--;
 658 }
 659
 660 static int empty_statement(struct statement *stmt)
 661 {
 662         if (!stmt)
 663                 return 0;
 664         if (stmt->type == STMT_EXPRESSION && !stmt->expression)
 665                 return 1;
 666         return 0;
 667 }
 668
 669 static int last_stmt_on_same_line(void)
 670 {
 671         struct statement *stmt;
 672         int i = 0;
 673
 674         FOR_EACH_PTR_REVERSE(big_statement_stack, stmt) {
 675                 if (!i++)
 676                         continue;
 677                 if  (stmt->pos.line == get_lineno())
 678                         return 1;
 679                 return 0;
 680         } END_FOR_EACH_PTR_REVERSE(stmt);
 681         return 0;
 682 }
 683
 684 static void split_asm_constraints(struct expression_list *expr_list)
 685 {
 686         struct expression *expr;
 687         int state = 0;
 688
 689         FOR_EACH_PTR(expr_list, expr) {
 690                 switch (state) {
 691                 case 0: /* identifier */
 692                 case 1: /* constraint */
 693                         state++;
 694                         continue;
 695                 case 2: /* expression */
 696                         state = 0;
 697                         __split_expr(expr);
 698                         continue;
 699                 }
 700         } END_FOR_EACH_PTR(expr);
 701 }
 702
 703 static int is_case_val(struct statement *stmt, sval_t sval)
 704 {
 705         sval_t case_sval;
 706
 707         if (stmt->type != STMT_CASE)
 708                 return 0;
 709         if (!stmt->case_expression) {
 710                 __set_default();
 711                 return 1;
 712         }
 713         if (!get_value(stmt->case_expression, &case_sval))
 714                 return 0;
 715         if (case_sval.value == sval.value)
 716                 return 1;
 717         return 0;
 718 }
 719
 720 static struct range_list *get_case_rl(struct expression *switch_expr,
 721                                       struct expression *case_expr,
 722                                       struct expression *case_to)
 723 {
 724         sval_t start, end;
 725         struct range_list *rl = NULL;
 726         struct symbol *switch_type;
 727
 728         switch_type = get_type(switch_expr);
 729         if (get_value(case_to, &end) && get_value(case_expr, &start)) {
 730                 start = sval_cast(switch_type, start);
 731                 end = sval_cast(switch_type, end);
 732                 add_range(&rl, start, end);
 733         } else if (get_value(case_expr, &start)) {
 734                 start = sval_cast(switch_type, start);
 735                 add_range(&rl, start, start);
 736         }
 737
 738         return rl;
 739 }
 740
 741 static void split_known_switch(struct statement *stmt, sval_t sval)
 742 {
 743         struct statement *tmp;
 744         struct range_list *rl;
 745
 746         __split_expr(stmt->switch_expression);
 747         sval = sval_cast(get_type(stmt->switch_expression), sval);
 748
 749         push_expression(&switch_expr_stack, stmt->switch_expression);
 750         __save_switch_states(top_expression(switch_expr_stack));
 751         nullify_path();
 752         __push_default();
 753         __push_breaks();
 754
 755         stmt = stmt->switch_statement;
 756
 757         __push_scope_hooks();
 758         FOR_EACH_PTR(stmt->stmts, tmp) {
 759                 __smatch_lineno = tmp->pos.line;
 760                 if (is_case_val(tmp, sval)) {
 761                         rl = alloc_rl(sval, sval);
 762                         __merge_switches(top_expression(switch_expr_stack), rl);
 763                         __pass_case_to_client(top_expression(switch_expr_stack), rl);
 764                 }
 765                 if (__path_is_null())
 766                         continue;
 767                 __split_stmt(tmp);
 768                 if (__path_is_null()) {
 769                         __set_default();
 770                         goto out;
 771                 }
 772         } END_FOR_EACH_PTR(tmp);
 773 out:
 774         __call_scope_hooks();
 775         if (!__pop_default())
 776                 __merge_switches(top_expression(switch_expr_stack), NULL);
 777         __discard_switches();
 778         __merge_breaks();
 779         pop_expression(&switch_expr_stack);
 780 }
 781
 782 static void split_case(struct statement *stmt)
 783 {
 784         struct range_list *rl = NULL;
 785
 786         expr_set_parent_stmt(stmt->case_expression, stmt);
 787         expr_set_parent_stmt(stmt->case_to, stmt);
 788
 789         rl = get_case_rl(top_expression(switch_expr_stack),
 790                          stmt->case_expression, stmt->case_to);
 791         while (stmt->case_statement->type == STMT_CASE) {
 792                 struct range_list *tmp;
 793
 794                 tmp = get_case_rl(top_expression(switch_expr_stack),
 795                                   stmt->case_statement->case_expression,
 796                                   stmt->case_statement->case_to);
 797                 if (!tmp)
 798                         break;
 799                 rl = rl_union(rl, tmp);
 800                 if (!stmt->case_expression)
 801                         __set_default();
 802                 stmt = stmt->case_statement;
 803         }
 804
 805         __merge_switches(top_expression(switch_expr_stack), rl);
 806
 807         if (!stmt->case_expression)
 808                 __set_default();
 809         __split_stmt(stmt->case_statement);
 810 }
 811
 812 int time_parsing_function(void)
 813 {
 814         return ms_since(&fn_start_time) / 1000;
 815 }
 816
 817 static int taking_too_long(void)
 818 {
 819         if (time_parsing_function() > 60 * 5)  /* five minutes */
 820                 return 1;
 821         return 0;
 822 }
 823
 824 static int is_last_stmt(struct statement *cur_stmt)
 825 {
 826         struct symbol *fn = get_base_type(cur_func_sym);
 827         struct statement *stmt;
 828
 829         if (!fn)
 830                 return 0;
 831         stmt = fn->stmt;
 832         if (!stmt)
 833                 stmt = fn->inline_stmt;
 834         if (!stmt || stmt->type != STMT_COMPOUND)
 835                 return 0;
 836         stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 837         if (stmt && stmt->type == STMT_LABEL)
 838                 stmt = stmt->label_statement;
 839         if (stmt == cur_stmt)
 840                 return 1;
 841         return 0;
 842 }
 843
 844 static void handle_backward_goto(struct statement *goto_stmt)
 845 {
 846         const char *goto_name, *label_name;
 847         struct statement *func_stmt;
 848         struct symbol *base_type = get_base_type(cur_func_sym);
 849         struct statement *tmp;
 850         int found = 0;
 851
 852         if (!option_info)
 853                 return;
 854         if (last_goto_statement_handled)
 855                 return;
 856         last_goto_statement_handled = 1;
 857
 858         if (!goto_stmt->goto_label ||
 859             goto_stmt->goto_label->type != SYM_LABEL ||
 860             !goto_stmt->goto_label->ident)
 861                 return;
 862         goto_name = goto_stmt->goto_label->ident->name;
 863
 864         func_stmt = base_type->stmt;
 865         if (!func_stmt)
 866                 func_stmt = base_type->inline_stmt;
 867         if (!func_stmt)
 868                 return;
 869         if (func_stmt->type != STMT_COMPOUND)
 870                 return;
 871
 872         FOR_EACH_PTR(func_stmt->stmts, tmp) {
 873                 if (!found) {
 874                         if (tmp->type != STMT_LABEL)
 875                                 continue;
 876                         if (!tmp->label_identifier ||
 877                             tmp->label_identifier->type != SYM_LABEL ||
 878                             !tmp->label_identifier->ident)
 879                                 continue;
 880                         label_name = tmp->label_identifier->ident->name;
 881                         if (strcmp(goto_name, label_name) != 0)
 882                                 continue;
 883                         found = 1;
 884                 }
 885                 __split_stmt(tmp);
 886         } END_FOR_EACH_PTR(tmp);
 887 }
 888
 889 static void fake_a_return(void)
 890 {
 891         struct symbol *return_type;
 892
 893         nullify_path();
 894         __unnullify_path();
 895
 896         return_type = get_real_base_type(cur_func_sym);
 897         return_type = get_real_base_type(return_type);
 898         if (return_type != &void_ctype) {
 899                 __pass_to_client(unknown_value_expression(NULL), RETURN_HOOK);
 900                 nullify_path();
 901         }
 902 }
 903
 904 static void fake_an_empty_default(struct position pos)
 905 {
 906         static struct statement none = {};
 907
 908         none.pos = pos;
 909         none.type = STMT_NONE;
 910         __merge_switches(top_expression(switch_expr_stack), NULL);
 911         __split_stmt(&none);
 912 }
 913
 914 static void split_compound(struct statement *stmt)
 915 {
 916         struct statement *prev = NULL;
 917         struct statement *cur = NULL;
 918         struct statement *next;
 919
 920         __push_scope_hooks();
 921
 922         FOR_EACH_PTR(stmt->stmts, next) {
 923                 /* just set them all ahead of time */
 924                 stmt_set_parent_stmt(next, stmt);
 925
 926                 if (cur) {
 927                         __prev_stmt = prev;
 928                         __next_stmt = next;
 929                         __cur_stmt = cur;
 930                         __split_stmt(cur);
 931                 }
 932                 prev = cur;
 933                 cur = next;
 934         } END_FOR_EACH_PTR(next);
 935         if (cur) {
 936                 __prev_stmt = prev;
 937                 __cur_stmt = cur;
 938                 __next_stmt = NULL;
 939                 __split_stmt(cur);
 940         }
 941
 942         /*
 943          * For function scope, then delay calling the scope hooks until the
 944          * end of function hooks can run.  I'm not positive this is the right
 945          * thing...
 946          */
 947         if (!is_last_stmt(cur))
 948                 __call_scope_hooks();
 949 }
 950
 951 /*
 952  * This is a hack, work around for detecting empty functions.
 953  */
 954 static int need_delayed_scope_hooks(void)
 955 {
 956         struct symbol *fn = get_base_type(cur_func_sym);
 957         struct statement *stmt;
 958
 959         if (!fn)
 960                 return 0;
 961         stmt = fn->stmt;
 962         if (!stmt)
 963                 stmt = fn->inline_stmt;
 964         if (stmt && stmt->type == STMT_COMPOUND)
 965                 return 1;
 966         return 0;
 967 }
 968
 969 void __split_label_stmt(struct statement *stmt)
 970 {
 971         if (stmt->label_identifier &&
 972             stmt->label_identifier->type == SYM_LABEL &&
 973             stmt->label_identifier->ident) {
 974                 loop_count |= 0x0800000;
 975                 __merge_gotos(stmt->label_identifier->ident->name, stmt->label_identifier);
 976         }
 977 }
 978
 979 static void find_asm_gotos(struct statement *stmt)
 980 {
 981         struct symbol *sym;
 982
 983         FOR_EACH_PTR(stmt->asm_labels, sym) {
 984                 __save_gotos(sym->ident->name, sym);
 985         } END_FOR_EACH_PTR(sym);
 986 }
 987
 988 void __split_stmt(struct statement *stmt)
 989 {
 990         sval_t sval;
 991
 992         if (!stmt)
 993                 goto out;
 994
 995         if (!__in_fake_assign)
 996                 __silence_warnings_for_stmt = false;
 997
 998         if (__bail_on_rest_of_function)
 999                 return;
1000
1001         if (out_of_memory() || taking_too_long()) {
1002                 struct timeval stop;
1003
1004                 gettimeofday(&stop, NULL);
1005
1006                 __bail_on_rest_of_function = 1;
1007                 final_pass = 1;
1008                 sm_msg("Function too hairy.  Giving up. %lu seconds",
1009                        stop.tv_sec - fn_start_time.tv_sec);
1010                 fake_a_return();
1011                 final_pass = 0;  /* turn off sm_msg() from here */
1012                 return;
1013         }
1014
1015         add_ptr_list(&big_statement_stack, stmt);
1016         free_expression_stack(&big_expression_stack);
1017         set_position(stmt->pos);
1018         __pass_to_client(stmt, STMT_HOOK);
1019
1020         switch (stmt->type) {
1021         case STMT_DECLARATION:
1022                 split_declaration(stmt->declaration);
1023                 break;
1024         case STMT_RETURN:
1025                 expr_set_parent_stmt(stmt->ret_value, stmt);
1026
1027                 __split_expr(stmt->ret_value);
1028                 __pass_to_client(stmt->ret_value, RETURN_HOOK);
1029                 __process_post_op_stack();
1030                 nullify_path();
1031                 break;
1032         case STMT_EXPRESSION:
1033                 expr_set_parent_stmt(stmt->expression, stmt);
1034                 expr_set_parent_stmt(stmt->context, stmt);
1035
1036                 __split_expr(stmt->expression);
1037                 break;
1038         case STMT_COMPOUND:
1039                 split_compound(stmt);
1040                 break;
1041         case STMT_IF:
1042                 stmt_set_parent_stmt(stmt->if_true, stmt);
1043                 stmt_set_parent_stmt(stmt->if_false, stmt);
1044                 expr_set_parent_stmt(stmt->if_conditional, stmt);
1045
1046                 if (known_condition_true(stmt->if_conditional)) {
1047                         __split_stmt(stmt->if_true);
1048                         break;
1049                 }
1050                 if (known_condition_false(stmt->if_conditional)) {
1051                         __split_stmt(stmt->if_false);
1052                         break;
1053                 }
1054                 __split_whole_condition(stmt->if_conditional);
1055                 __split_stmt(stmt->if_true);
1056                 if (empty_statement(stmt->if_true) &&
1057                         last_stmt_on_same_line() &&
1058                         !get_macro_name(stmt->if_true->pos))
1059                         sm_msg("warn: if();");
1060                 __push_true_states();
1061                 __use_false_states();
1062                 __split_stmt(stmt->if_false);
1063                 __merge_true_states();
1064                 break;
1065         case STMT_ITERATOR:
1066                 stmt_set_parent_stmt(stmt->iterator_pre_statement, stmt);
1067                 stmt_set_parent_stmt(stmt->iterator_statement, stmt);
1068                 stmt_set_parent_stmt(stmt->iterator_post_statement, stmt);
1069                 expr_set_parent_stmt(stmt->iterator_pre_condition, stmt);
1070                 expr_set_parent_stmt(stmt->iterator_post_condition, stmt);
1071
1072                 if (stmt->iterator_pre_condition)
1073                         handle_pre_loop(stmt);
1074                 else if (stmt->iterator_post_condition)
1075                         handle_post_loop(stmt);
1076                 else {
1077                         // these are for(;;) type loops.
1078                         handle_pre_loop(stmt);
1079                 }
1080                 break;
1081         case STMT_SWITCH:
1082                 stmt_set_parent_stmt(stmt->switch_statement, stmt);
1083                 expr_set_parent_stmt(stmt->switch_expression, stmt);
1084
1085                 if (get_value(stmt->switch_expression, &sval)) {
1086                         split_known_switch(stmt, sval);
1087                         break;
1088                 }
1089                 __split_expr(stmt->switch_expression);
1090                 push_expression(&switch_expr_stack, stmt->switch_expression);
1091                 __save_switch_states(top_expression(switch_expr_stack));
1092                 nullify_path();
1093                 __push_default();
1094                 __push_breaks();
1095                 __split_stmt(stmt->switch_statement);
1096                 if (!__pop_default() && have_remaining_cases())
1097                         fake_an_empty_default(stmt->pos);
1098                 __discard_switches();
1099                 __merge_breaks();
1100                 pop_expression(&switch_expr_stack);
1101                 break;
1102         case STMT_CASE:
1103                 split_case(stmt);
1104                 break;
1105         case STMT_LABEL:
1106                 __split_label_stmt(stmt);
1107                 __split_stmt(stmt->label_statement);
1108                 break;
1109         case STMT_GOTO:
1110                 expr_set_parent_stmt(stmt->goto_expression, stmt);
1111
1112                 __split_expr(stmt->goto_expression);
1113                 if (stmt->goto_label && stmt->goto_label->type == SYM_NODE) {
1114                         if (!strcmp(stmt->goto_label->ident->name, "break")) {
1115                                 __process_breaks();
1116                         } else if (!strcmp(stmt->goto_label->ident->name,
1117                                            "continue")) {
1118                                 __process_continues();
1119                         }
1120                 } else if (stmt->goto_label &&
1121                            stmt->goto_label->type == SYM_LABEL &&
1122                            stmt->goto_label->ident) {
1123                         __save_gotos(stmt->goto_label->ident->name, stmt->goto_label);
1124                 }
1125                 nullify_path();
1126                 if (is_last_stmt(stmt))
1127                         handle_backward_goto(stmt);
1128                 break;
1129         case STMT_NONE:
1130                 break;
1131         case STMT_ASM:
1132                 expr_set_parent_stmt(stmt->asm_string, stmt);
1133
1134                 find_asm_gotos(stmt);
1135                 __pass_to_client(stmt, ASM_HOOK);
1136                 __split_expr(stmt->asm_string);
1137                 split_asm_constraints(stmt->asm_outputs);
1138                 split_asm_constraints(stmt->asm_inputs);
1139                 split_asm_constraints(stmt->asm_clobbers);
1140                 break;
1141         case STMT_CONTEXT:
1142                 break;
1143         case STMT_RANGE:
1144                 __split_expr(stmt->range_expression);
1145                 __split_expr(stmt->range_low);
1146                 __split_expr(stmt->range_high);
1147                 break;
1148         }
1149         __pass_to_client(stmt, STMT_HOOK_AFTER);
1150 out:
1151         __process_post_op_stack();
1152 }
1153
1154 static void split_expr_list(struct expression_list *expr_list, struct expression *parent)
1155 {
1156         struct expression *expr;
1157
1158         FOR_EACH_PTR(expr_list, expr) {
1159                 expr_set_parent_expr(expr, parent);
1160                 __split_expr(expr);
1161                 __process_post_op_stack();
1162         } END_FOR_EACH_PTR(expr);
1163 }
1164
1165 static void split_sym(struct symbol *sym)
1166 {
1167         if (!sym)
1168                 return;
1169         if (!(sym->namespace & NS_SYMBOL))
1170                 return;
1171
1172         __split_stmt(sym->stmt);
1173         __split_expr(sym->array_size);
1174         split_symlist(sym->arguments);
1175         split_symlist(sym->symbol_list);
1176         __split_stmt(sym->inline_stmt);
1177         split_symlist(sym->inline_symbol_list);
1178 }
1179
1180 static void split_symlist(struct symbol_list *sym_list)
1181 {
1182         struct symbol *sym;
1183
1184         FOR_EACH_PTR(sym_list, sym) {
1185                 split_sym(sym);
1186         } END_FOR_EACH_PTR(sym);
1187 }
1188
1189 typedef void (fake_cb)(struct expression *expr);
1190
1191 static int member_to_number(struct expression *expr, struct ident *member)
1192 {
1193         struct symbol *type, *tmp;
1194         char *name;
1195         int i;
1196
1197         if (!member)
1198                 return -1;
1199         name = member->name;
1200
1201         type = get_type(expr);
1202         if (!type || type->type != SYM_STRUCT)
1203                 return -1;
1204
1205         i = -1;
1206         FOR_EACH_PTR(type->symbol_list, tmp) {
1207                 i++;
1208                 if (!tmp->ident)
1209                         continue;
1210                 if (strcmp(name, tmp->ident->name) == 0)
1211                         return i;
1212         } END_FOR_EACH_PTR(tmp);
1213         return -1;
1214 }
1215
1216 static struct ident *number_to_member(struct expression *expr, int num)
1217 {
1218         struct symbol *type, *member;
1219         int i = 0;
1220
1221         type = get_type(expr);
1222         if (!type || type->type != SYM_STRUCT)
1223                 return NULL;
1224
1225         FOR_EACH_PTR(type->symbol_list, member) {
1226                 if (i == num)
1227                         return member->ident;
1228                 i++;
1229         } END_FOR_EACH_PTR(member);
1230         return NULL;
1231 }
1232
1233 static void fake_element_assigns_helper(struct expression *array, struct expression_list *expr_list, fake_cb *fake_cb);
1234
1235 static void set_inner_struct_members(struct expression *expr, struct symbol *member)
1236 {
1237         struct expression *edge_member, *assign;
1238         struct symbol *base = get_real_base_type(member);
1239         struct symbol *tmp;
1240
1241         if (member->ident)
1242                 expr = member_expression(expr, '.', member->ident);
1243
1244         FOR_EACH_PTR(base->symbol_list, tmp) {
1245                 struct symbol *type;
1246
1247                 type = get_real_base_type(tmp);
1248                 if (!type)
1249                         continue;
1250
1251                 edge_member = member_expression(expr, '.', tmp->ident);
1252                 if (get_extra_state(edge_member))
1253                         continue;
1254
1255                 if (type->type == SYM_UNION || type->type == SYM_STRUCT) {
1256                         set_inner_struct_members(expr, tmp);
1257                         continue;
1258                 }
1259
1260                 if (!tmp->ident)
1261                         continue;
1262
1263                 assign = assign_expression(edge_member, '=', zero_expr());
1264                 __split_expr(assign);
1265         } END_FOR_EACH_PTR(tmp);
1266
1267
1268 }
1269
1270 static void set_unset_to_zero(struct symbol *type, struct expression *expr)
1271 {
1272         struct symbol *tmp;
1273         struct expression *member = NULL;
1274         struct expression *assign;
1275         int op = '*';
1276
1277         if (expr->type == EXPR_PREOP && expr->op == '&') {
1278                 expr = strip_expr(expr->unop);
1279                 op = '.';
1280         }
1281
1282         FOR_EACH_PTR(type->symbol_list, tmp) {
1283                 type = get_real_base_type(tmp);
1284                 if (!type)
1285                         continue;
1286
1287                 if (tmp->ident) {
1288                         member = member_expression(expr, op, tmp->ident);
1289                         if (get_extra_state(member))
1290                                 continue;
1291                 }
1292
1293                 if (type->type == SYM_UNION || type->type == SYM_STRUCT) {
1294                         set_inner_struct_members(expr, tmp);
1295                         continue;
1296                 }
1297                 if (type->type == SYM_ARRAY)
1298                         continue;
1299                 if (!tmp->ident)
1300                         continue;
1301
1302                 assign = assign_expression(member, '=', zero_expr());
1303                 __split_expr(assign);
1304         } END_FOR_EACH_PTR(tmp);
1305 }
1306
1307 static void fake_member_assigns_helper(struct expression *symbol, struct expression_list *members, fake_cb *fake_cb)
1308 {
1309         struct expression *deref, *assign, *tmp, *right;
1310         struct symbol *struct_type, *type;
1311         struct ident *member;
1312         int member_idx;
1313
1314         struct_type = get_type(symbol);
1315         if (!struct_type ||
1316             (struct_type->type != SYM_STRUCT && struct_type->type != SYM_UNION))
1317                 return;
1318
1319         /*
1320          * We're parsing an initializer that could look something like this:
1321          * struct foo foo = {
1322          *      42,
1323          *      .whatever.xxx = 11,
1324          *      .zzz = 12,
1325          * };
1326          *
1327          * So what we have here is a list with 42, .whatever, and .zzz.  We need
1328          * to break it up into left and right sides of the assignments.
1329          *
1330          */
1331         member_idx = 0;
1332         FOR_EACH_PTR(members, tmp) {
1333                 deref = NULL;
1334                 if (tmp->type == EXPR_IDENTIFIER) {
1335                         member_idx = member_to_number(symbol, tmp->expr_ident);
1336                         while (tmp->type == EXPR_IDENTIFIER) {
1337                                 member = tmp->expr_ident;
1338                                 tmp = tmp->ident_expression;
1339                                 if (deref)
1340                                         deref = member_expression(deref, '.', member);
1341                                 else
1342                                         deref = member_expression(symbol, '.', member);
1343                         }
1344                 } else {
1345                         member = number_to_member(symbol, member_idx);
1346                         deref = member_expression(symbol, '.', member);
1347                 }
1348                 right = tmp;
1349                 member_idx++;
1350                 if (right->type == EXPR_INITIALIZER) {
1351                         type = get_type(deref);
1352                         if (type && type->type == SYM_ARRAY)
1353                                 fake_element_assigns_helper(deref, right->expr_list, fake_cb);
1354                         else
1355                                 fake_member_assigns_helper(deref, right->expr_list, fake_cb);
1356                 } else {
1357                         assign = assign_expression(deref, '=', right);
1358                         fake_cb(assign);
1359                 }
1360         } END_FOR_EACH_PTR(tmp);
1361
1362         set_unset_to_zero(struct_type, symbol);
1363 }
1364
1365 static void fake_member_assigns(struct symbol *sym, fake_cb *fake_cb)
1366 {
1367         fake_member_assigns_helper(symbol_expression(sym),
1368                                    sym->initializer->expr_list, fake_cb);
1369 }
1370
1371 static void fake_element_assigns_helper(struct expression *array, struct expression_list *expr_list, fake_cb *fake_cb)
1372 {
1373         struct expression *offset, *binop, *assign, *tmp;
1374         struct symbol *type;
1375         int idx;
1376
1377         if (ptr_list_size((struct ptr_list *)expr_list) > 1000)
1378                 return;
1379
1380         idx = 0;
1381         FOR_EACH_PTR(expr_list, tmp) {
1382                 if (tmp->type == EXPR_INDEX) {
1383                         if (tmp->idx_from != tmp->idx_to)
1384                                 return;
1385                         idx = tmp->idx_from;
1386                         if (!tmp->idx_expression)
1387                                 goto next;
1388                         tmp = tmp->idx_expression;
1389                 }
1390                 offset = value_expr(idx);
1391                 binop = array_element_expression(array, offset);
1392                 if (tmp->type == EXPR_INITIALIZER) {
1393                         type = get_type(binop);
1394                         if (type && type->type == SYM_ARRAY)
1395                                 fake_element_assigns_helper(binop, tmp->expr_list, fake_cb);
1396                         else
1397                                 fake_member_assigns_helper(binop, tmp->expr_list, fake_cb);
1398                 } else {
1399                         assign = assign_expression(binop, '=', tmp);
1400                         fake_cb(assign);
1401                 }
1402 next:
1403                 idx++;
1404         } END_FOR_EACH_PTR(tmp);
1405 }
1406
1407 static void fake_element_assigns(struct symbol *sym, fake_cb *fake_cb)
1408 {
1409         fake_element_assigns_helper(symbol_expression(sym), sym->initializer->expr_list, fake_cb);
1410 }
1411
1412 static void fake_assign_expr(struct symbol *sym)
1413 {
1414         struct expression *assign, *symbol;
1415
1416         symbol = symbol_expression(sym);
1417         assign = assign_expression(symbol, '=', sym->initializer);
1418         __split_expr(assign);
1419 }
1420
1421 static void call_split_expr(struct expression *expr)
1422 {
1423         __split_expr(expr);
1424 }
1425
1426 static void do_initializer_stuff(struct symbol *sym)
1427 {
1428         if (!sym->initializer)
1429                 return;
1430
1431         if (sym->initializer->type == EXPR_INITIALIZER) {
1432                 if (get_real_base_type(sym)->type == SYM_ARRAY)
1433                         fake_element_assigns(sym, call_split_expr);
1434                 else
1435                         fake_member_assigns(sym, call_split_expr);
1436         } else {
1437                 fake_assign_expr(sym);
1438         }
1439 }
1440
1441 static void split_declaration(struct symbol_list *sym_list)
1442 {
1443         struct symbol *sym;
1444
1445         FOR_EACH_PTR(sym_list, sym) {
1446                 __pass_to_client(sym, DECLARATION_HOOK);
1447                 do_initializer_stuff(sym);
1448                 split_sym(sym);
1449         } END_FOR_EACH_PTR(sym);
1450 }
1451
1452 static void call_global_assign_hooks(struct expression *assign)
1453 {
1454         __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1455 }
1456
1457 static void fake_global_assign(struct symbol *sym)
1458 {
1459         struct expression *assign, *symbol;
1460
1461         if (get_real_base_type(sym)->type == SYM_ARRAY) {
1462                 if (sym->initializer && sym->initializer->type == EXPR_INITIALIZER) {
1463                         fake_element_assigns(sym, call_global_assign_hooks);
1464                 } else if (sym->initializer) {
1465                         symbol = symbol_expression(sym);
1466                         assign = assign_expression(symbol, '=', sym->initializer);
1467                         __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1468                 } else {
1469                         fake_element_assigns_helper(symbol_expression(sym), NULL, call_global_assign_hooks);
1470                 }
1471         } else if (get_real_base_type(sym)->type == SYM_STRUCT) {
1472                 if (sym->initializer && sym->initializer->type == EXPR_INITIALIZER) {
1473                         fake_member_assigns(sym, call_global_assign_hooks);
1474                 } else if (sym->initializer) {
1475                         symbol = symbol_expression(sym);
1476                         assign = assign_expression(symbol, '=', sym->initializer);
1477                         __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1478                 } else {
1479                         fake_member_assigns_helper(symbol_expression(sym), NULL, call_global_assign_hooks);
1480                 }
1481         } else {
1482                 symbol = symbol_expression(sym);
1483                 if (sym->initializer)
1484                         assign = assign_expression(symbol, '=', sym->initializer);
1485                 else
1486                         assign = assign_expression(symbol, '=', zero_expr());
1487                 __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1488         }
1489 }
1490
1491 static void start_function_definition(struct symbol *sym)
1492 {
1493         __in_function_def = 1;
1494         __pass_to_client(sym, FUNC_DEF_HOOK);
1495         __in_function_def = 0;
1496         __pass_to_client(sym, AFTER_DEF_HOOK);
1497
1498 }
1499
1500 static void split_function(struct symbol *sym)
1501 {
1502         struct symbol *base_type = get_base_type(sym);
1503
1504         if (!base_type->stmt && !base_type->inline_stmt)
1505                 return;
1506
1507         gettimeofday(&fn_start_time, NULL);
1508         cur_func_sym = sym;
1509         if (sym->ident)
1510                 cur_func = sym->ident->name;
1511         set_position(sym->pos);
1512         loop_count = 0;
1513         last_goto_statement_handled = 0;
1514         sm_debug("new function:  %s\n", cur_func);
1515         __stree_id = 0;
1516         if (option_two_passes) {
1517                 __unnullify_path();
1518                 loop_num = 0;
1519                 final_pass = 0;
1520                 start_function_definition(sym);
1521                 __split_stmt(base_type->stmt);
1522                 __split_stmt(base_type->inline_stmt);
1523                 nullify_path();
1524         }
1525         __unnullify_path();
1526         loop_num = 0;
1527         final_pass = 1;
1528         start_function_definition(sym);
1529         __split_stmt(base_type->stmt);
1530         __split_stmt(base_type->inline_stmt);
1531         __pass_to_client(sym, END_FUNC_HOOK);
1532         if (need_delayed_scope_hooks())
1533                 __call_scope_hooks();
1534         __pass_to_client(sym, AFTER_FUNC_HOOK);
1535
1536         clear_all_states();
1537         cur_func_sym = NULL;
1538         cur_func = NULL;
1539         free_data_info_allocs();
1540         free_expression_stack(&switch_expr_stack);
1541         __free_ptr_list((struct ptr_list **)&big_statement_stack);
1542         __bail_on_rest_of_function = 0;
1543 }
1544
1545 static void save_flow_state(void)
1546 {
1547         __add_ptr_list(&backup, INT_PTR(loop_num << 2), 0);
1548         __add_ptr_list(&backup, INT_PTR(loop_count << 2), 0);
1549         __add_ptr_list(&backup, INT_PTR(final_pass << 2), 0);
1550
1551         __add_ptr_list(&backup, big_statement_stack, 0);
1552         __add_ptr_list(&backup, big_expression_stack, 0);
1553         __add_ptr_list(&backup, big_condition_stack, 0);
1554         __add_ptr_list(&backup, switch_expr_stack, 0);
1555
1556         __add_ptr_list(&backup, cur_func_sym, 0);
1557
1558         __add_ptr_list(&backup, __prev_stmt, 0);
1559         __add_ptr_list(&backup, __cur_stmt, 0);
1560         __add_ptr_list(&backup, __next_stmt, 0);
1561
1562 }
1563
1564 static void *pop_backup(void)
1565 {
1566         void *ret;
1567
1568         ret = last_ptr_list(backup);
1569         delete_ptr_list_last(&backup);
1570         return ret;
1571 }
1572
1573 static void restore_flow_state(void)
1574 {
1575         __next_stmt = pop_backup();
1576         __cur_stmt = pop_backup();
1577         __prev_stmt = pop_backup();
1578
1579         cur_func_sym = pop_backup();
1580         switch_expr_stack = pop_backup();
1581         big_condition_stack = pop_backup();
1582         big_expression_stack = pop_backup();
1583         big_statement_stack = pop_backup();
1584         final_pass = PTR_INT(pop_backup()) >> 2;
1585         loop_count = PTR_INT(pop_backup()) >> 2;
1586         loop_num = PTR_INT(pop_backup()) >> 2;
1587 }
1588
1589 static void parse_inline(struct expression *call)
1590 {
1591         struct symbol *base_type;
1592         char *cur_func_bak = cur_func;  /* not aligned correctly for backup */
1593         struct timeval time_backup = fn_start_time;
1594
1595         save_flow_state();
1596
1597         __pass_to_client(call, INLINE_FN_START);
1598         final_pass = 0;  /* don't print anything */
1599         __inline_fn = call;
1600
1601         base_type = get_base_type(call->fn->symbol);
1602         cur_func_sym = call->fn->symbol;
1603         if (call->fn->symbol->ident)
1604                 cur_func = call->fn->symbol->ident->name;
1605         else
1606                 cur_func = NULL;
1607         set_position(call->fn->symbol->pos);
1608
1609         save_all_states();
1610         big_statement_stack = NULL;
1611         big_expression_stack = NULL;
1612         big_condition_stack = NULL;
1613         switch_expr_stack = NULL;
1614
1615         sm_debug("inline function:  %s\n", cur_func);
1616         __unnullify_path();
1617         loop_num = 0;
1618         loop_count = 0;
1619         start_function_definition(call->fn->symbol);
1620         __split_stmt(base_type->stmt);
1621         __split_stmt(base_type->inline_stmt);
1622         __pass_to_client(call->fn->symbol, END_FUNC_HOOK);
1623         __pass_to_client(call->fn->symbol, AFTER_FUNC_HOOK);
1624
1625         free_expression_stack(&switch_expr_stack);
1626         __free_ptr_list((struct ptr_list **)&big_statement_stack);
1627         nullify_path();
1628         free_goto_stack();
1629
1630         restore_flow_state();
1631         fn_start_time = time_backup;
1632         cur_func = cur_func_bak;
1633
1634         restore_all_states();
1635         set_position(call->pos);
1636         __inline_fn = NULL;
1637         __pass_to_client(call, INLINE_FN_END);
1638 }
1639
1640 static struct symbol_list *inlines_called;
1641 static void add_inline_function(struct symbol *sym)
1642 {
1643         static struct symbol_list *already_added;
1644         struct symbol *tmp;
1645
1646         FOR_EACH_PTR(already_added, tmp) {
1647                 if (tmp == sym)
1648                         return;
1649         } END_FOR_EACH_PTR(tmp);
1650
1651         add_ptr_list(&already_added, sym);
1652         add_ptr_list(&inlines_called, sym);
1653 }
1654
1655 static void process_inlines(void)
1656 {
1657         struct symbol *tmp;
1658
1659         FOR_EACH_PTR(inlines_called, tmp) {
1660                 split_function(tmp);
1661         } END_FOR_EACH_PTR(tmp);
1662         free_ptr_list(&inlines_called);
1663 }
1664
1665 static struct symbol *get_last_scoped_symbol(struct symbol_list *big_list, int use_static)
1666 {
1667         struct symbol *sym;
1668
1669         FOR_EACH_PTR_REVERSE(big_list, sym) {
1670                 if (!sym->scope)
1671                         continue;
1672                 if (use_static && sym->ctype.modifiers & MOD_STATIC)
1673                         return sym;
1674                 if (!use_static && !(sym->ctype.modifiers & MOD_STATIC))
1675                         return sym;
1676         } END_FOR_EACH_PTR_REVERSE(sym);
1677
1678         return NULL;
1679 }
1680
1681 static bool interesting_function(struct symbol *sym)
1682 {
1683         static int prev_stream = -1;
1684         static bool prev_answer;
1685         const char *filename;
1686         int len;
1687
1688         if (!(sym->ctype.modifiers & MOD_INLINE))
1689                 return true;
1690
1691         if (sym->pos.stream == prev_stream)
1692                 return prev_answer;
1693
1694         prev_stream = sym->pos.stream;
1695         prev_answer = false;
1696
1697         filename = stream_name(sym->pos.stream);
1698         len = strlen(filename);
1699         if (len > 0 && filename[len - 1] == 'c')
1700                 prev_answer = true;
1701         return prev_answer;
1702 }
1703
1704 static void split_inlines_in_scope(struct symbol *sym)
1705 {
1706         struct symbol *base;
1707         struct symbol_list *scope_list;
1708         int stream;
1709
1710         scope_list = sym->scope->symbols;
1711         stream = sym->pos.stream;
1712
1713         /* find the last static symbol in the file */
1714         FOR_EACH_PTR_REVERSE(scope_list, sym) {
1715                 if (sym->pos.stream != stream)
1716                         continue;
1717                 if (sym->type != SYM_NODE)
1718                         continue;
1719                 base = get_base_type(sym);
1720                 if (!base)
1721                         continue;
1722                 if (base->type != SYM_FN)
1723                         continue;
1724                 if (!base->inline_stmt)
1725                         continue;
1726                 if (!interesting_function(sym))
1727                         continue;
1728                 add_inline_function(sym);
1729         } END_FOR_EACH_PTR_REVERSE(sym);
1730
1731         process_inlines();
1732 }
1733
1734 static void split_inlines(struct symbol_list *sym_list)
1735 {
1736         struct symbol *sym;
1737
1738         sym = get_last_scoped_symbol(sym_list, 0);
1739         if (sym)
1740                 split_inlines_in_scope(sym);
1741         sym = get_last_scoped_symbol(sym_list, 1);
1742         if (sym)
1743                 split_inlines_in_scope(sym);
1744 }
1745
1746 static struct stree *clone_estates_perm(struct stree *orig)
1747 {
1748         struct stree *ret = NULL;
1749         struct sm_state *tmp;
1750
1751         FOR_EACH_SM(orig, tmp) {
1752                 set_state_stree_perm(&ret, tmp->owner, tmp->name, tmp->sym, clone_estate_perm(tmp->state));
1753         } END_FOR_EACH_SM(tmp);
1754
1755         return ret;
1756 }
1757
1758 struct position last_pos;
1759 static void split_c_file_functions(struct symbol_list *sym_list)
1760 {
1761         struct symbol *sym;
1762
1763         __unnullify_path();
1764         FOR_EACH_PTR(sym_list, sym) {
1765                 set_position(sym->pos);
1766                 if (sym->type != SYM_NODE || get_base_type(sym)->type != SYM_FN) {
1767                         __pass_to_client(sym, BASE_HOOK);
1768                         fake_global_assign(sym);
1769                 }
1770         } END_FOR_EACH_PTR(sym);
1771         global_states = clone_estates_perm(get_all_states_stree(SMATCH_EXTRA));
1772         nullify_path();
1773
1774         FOR_EACH_PTR(sym_list, sym) {
1775                 set_position(sym->pos);
1776                 last_pos = sym->pos;
1777                 if (!interesting_function(sym))
1778                         continue;
1779                 if (sym->type == SYM_NODE && get_base_type(sym)->type == SYM_FN) {
1780                         split_function(sym);
1781                         process_inlines();
1782                 }
1783                 last_pos = sym->pos;
1784         } END_FOR_EACH_PTR(sym);
1785         split_inlines(sym_list);
1786         __pass_to_client(sym_list, END_FILE_HOOK);
1787 }
1788
1789 static int final_before_fake;
1790 void init_fake_env(void)
1791 {
1792         if (!in_fake_env)
1793                 final_before_fake = final_pass;
1794         in_fake_env++;
1795         __push_fake_cur_stree();
1796         final_pass = 0;
1797 }
1798
1799 void end_fake_env(void)
1800 {
1801         __pop_fake_cur_stree();
1802         in_fake_env--;
1803         if (!in_fake_env)
1804                 final_pass = final_before_fake;
1805 }
1806
1807 static void open_output_files(char *base_file)
1808 {
1809         char buf[256];
1810
1811         snprintf(buf, sizeof(buf), "%s.smatch", base_file);
1812         sm_outfd = fopen(buf, "w");
1813         if (!sm_outfd) {
1814                 printf("Error:  Cannot open %s\n", buf);
1815                 exit(1);
1816         }
1817
1818         if (!option_info)
1819                 return;
1820
1821         snprintf(buf, sizeof(buf), "%s.smatch.sql", base_file);
1822         sql_outfd = fopen(buf, "w");
1823         if (!sql_outfd) {
1824                 printf("Error:  Cannot open %s\n", buf);
1825                 exit(1);
1826         }
1827
1828         snprintf(buf, sizeof(buf), "%s.smatch.caller_info", base_file);
1829         caller_info_fd = fopen(buf, "w");
1830         if (!caller_info_fd) {
1831                 printf("Error:  Cannot open %s\n", buf);
1832                 exit(1);
1833         }
1834 }
1835
1836 void smatch(int argc, char **argv)
1837 {
1838         struct string_list *filelist = NULL;
1839         struct symbol_list *sym_list;
1840         struct timeval stop, start;
1841
1842         gettimeofday(&start, NULL);
1843
1844         if (argc < 2) {
1845                 printf("Usage:  smatch [--debug] <filename.c>\n");
1846                 exit(1);
1847         }
1848         sparse_initialize(argc, argv, &filelist);
1849         set_valid_ptr_max();
1850         FOR_EACH_PTR_NOTAG(filelist, base_file) {
1851                 if (option_file_output)
1852                         open_output_files(base_file);
1853                 sym_list = sparse_keep_tokens(base_file);
1854                 split_c_file_functions(sym_list);
1855         } END_FOR_EACH_PTR_NOTAG(base_file);
1856
1857         gettimeofday(&stop, NULL);
1858
1859         set_position(last_pos);
1860         if (option_time)
1861                 sm_msg("time: %lu", stop.tv_sec - start.tv_sec);
1862         if (option_mem)
1863                 sm_msg("mem: %luKb", get_max_memory());
1864 }