smatch_flow.c

   1 /*
   2  * sparse/smatch_flow.c
   3  *
   4  * Copyright (C) 2006,2008 Dan Carpenter.
   5  *
   6  *  Licensed under the Open Software License version 1.1
   7  *
   8  */
   9
  10 #define _GNU_SOURCE 1
  11 #include <unistd.h>
  12 #include <stdio.h>
  13 #include "token.h"
  14 #include "smatch.h"
  15 #include "smatch_expression_stacks.h"
  16 #include "smatch_extra.h"
  17 #include "smatch_slist.h"
  18
  19 int final_pass;
  20
  21 static int __smatch_lineno = 0;
  22
  23 static char *base_file;
  24 static const char *filename;
  25 static char *pathname;
  26 static char *full_filename;
  27 static char *cur_func;
  28 static int line_func_start;
  29 static int loop_count;
  30 int __expr_stmt_count;
  31 static struct expression_list *switch_expr_stack = NULL;
  32
  33 struct expression_list *big_expression_stack;
  34 struct statement_list *big_statement_stack;
  35 int __in_pre_condition = 0;
  36 int __bail_on_rest_of_function = 0;
  37 char *get_function(void) { return cur_func; }
  38 int get_lineno(void) { return __smatch_lineno; }
  39 int inside_loop(void) { return !!loop_count; }
  40 int in_expression_statement(void) { return !!__expr_stmt_count; }
  41
  42 static void split_symlist(struct symbol_list *sym_list);
  43 static void split_declaration(struct symbol_list *sym_list);
  44 static void split_expr_list(struct expression_list *expr_list);
  45 static void add_inline_function(struct symbol *sym);
  46
  47 int option_assume_loops = 0;
  48 int option_known_conditions = 0;
  49 int option_two_passes = 0;
  50 struct symbol *cur_func_sym = NULL;
  51
  52 const char *get_filename(void)
  53 {
  54         if (option_info)
  55                 return base_file;
  56         if (option_full_path)
  57                 return full_filename;
  58         return filename;
  59 }
  60
  61 static void set_position(struct position pos)
  62 {
  63         int len;
  64         static int prev_stream = -1;
  65
  66         __smatch_lineno = pos.line;
  67
  68         if (pos.stream == prev_stream)
  69                 return;
  70
  71         filename = stream_name(pos.stream);
  72
  73         free(full_filename);
  74         pathname = getcwd(NULL, 0);
  75         if (pathname) {
  76                 len = strlen(pathname) + 1 + strlen(filename) + 1;
  77                 full_filename = malloc(len);
  78                 snprintf(full_filename, len, "%s/%s", pathname, filename);
  79         } else {
  80                 full_filename = alloc_string(filename);
  81         }
  82         free(pathname);
  83 }
  84
  85 static int is_inline_func(struct expression *expr)
  86 {
  87         if (expr->type != EXPR_SYMBOL || !expr->symbol)
  88                 return 0;
  89         if (expr->symbol->ctype.modifiers & MOD_INLINE)
  90                 return 1;
  91         return 0;
  92 }
  93
  94 void __split_expr(struct expression *expr)
  95 {
  96         if (!expr)
  97                 return;
  98
  99         // sm_msg(" Debug expr_type %d %s", expr->type, show_special(expr->op));
 100
 101         push_expression(&big_expression_stack, expr);
 102         set_position(expr->pos);
 103         __pass_to_client(expr, EXPR_HOOK);
 104
 105         switch (expr->type) {
 106         case EXPR_PREOP:
 107                 if (expr->op == '*')
 108                         __pass_to_client(expr, DEREF_HOOK);
 109         case EXPR_POSTOP:
 110                 __pass_to_client(expr, OP_HOOK);
 111                 __split_expr(expr->unop);
 112                 break;
 113         case EXPR_STATEMENT:
 114                 __expr_stmt_count++;
 115                 __split_stmt(expr->statement);
 116                 __expr_stmt_count--;
 117                 break;
 118         case EXPR_LOGICAL:
 119         case EXPR_COMPARE:
 120                 __pass_to_client(expr, LOGIC_HOOK);
 121                 __handle_logic(expr);
 122                 break;
 123         case EXPR_BINOP:
 124                 __pass_to_client(expr, BINOP_HOOK);
 125         case EXPR_COMMA:
 126                 __split_expr(expr->left);
 127                 __split_expr(expr->right);
 128                 break;
 129         case EXPR_ASSIGNMENT: {
 130                 struct expression *tmp;
 131
 132                 if (!expr->right)
 133                         break;
 134
 135                 __pass_to_client(expr, RAW_ASSIGNMENT_HOOK);
 136
 137                 /* foo = !bar() */
 138                 if (__handle_condition_assigns(expr))
 139                         break;
 140                 /* foo = (x < 5 ? foo : 5); */
 141                 if (__handle_select_assigns(expr))
 142                         break;
 143                 /* foo = ({frob(); frob(); frob(); 1;}) */
 144                 if (__handle_expr_statement_assigns(expr))
 145                         break;
 146
 147                 __split_expr(expr->right);
 148                 __pass_to_client(expr, ASSIGNMENT_HOOK);
 149                 tmp = strip_expr(expr->right);
 150                 if (tmp->type == EXPR_CALL)
 151                         __pass_to_client(expr, CALL_ASSIGNMENT_HOOK);
 152                 if (get_macro_name(tmp->pos))
 153                         __pass_to_client(expr, MACRO_ASSIGNMENT_HOOK);
 154                 __split_expr(expr->left);
 155                 break;
 156         }
 157         case EXPR_DEREF:
 158                 __pass_to_client(expr, DEREF_HOOK);
 159                 __split_expr(expr->deref);
 160                 break;
 161         case EXPR_SLICE:
 162                 __split_expr(expr->base);
 163                 break;
 164         case EXPR_CAST:
 165         case EXPR_FORCE_CAST:
 166                 __pass_to_client(expr, CAST_HOOK);
 167                 __split_expr(expr->cast_expression);
 168                 break;
 169         case EXPR_SIZEOF:
 170                 /* there isn't anything to pass a client from inside a sizeof() */
 171                 break;
 172         case EXPR_CONDITIONAL:
 173         case EXPR_SELECT:
 174                 if (known_condition_true(expr->conditional)) {
 175                         __split_expr(expr->cond_true);
 176                         break;
 177                 }
 178                 if (known_condition_false(expr->conditional)) {
 179                         __split_expr(expr->cond_false);
 180                         break;
 181                 }
 182                 __pass_to_client(expr, SELECT_HOOK);
 183                 __split_whole_condition(expr->conditional);
 184                 __split_expr(expr->cond_true);
 185                 __push_true_states();
 186                 __use_false_states();
 187                 __split_expr(expr->cond_false);
 188                 __merge_true_states();
 189                 break;
 190         case EXPR_CALL:
 191                 if (sym_name_is("__builtin_constant_p", expr->fn))
 192                         break;
 193                 split_expr_list(expr->args);
 194                 __split_expr(expr->fn);
 195                 if (is_inline_func(expr->fn))
 196                         add_inline_function(expr->fn->symbol);
 197                 __pass_to_client(expr, FUNCTION_CALL_HOOK);
 198                 break;
 199         case EXPR_INITIALIZER:
 200                 split_expr_list(expr->expr_list);
 201                 break;
 202         case EXPR_IDENTIFIER:
 203                 __split_expr(expr->ident_expression);
 204                 break;
 205         case EXPR_INDEX:
 206                 __split_expr(expr->idx_expression);
 207                 break;
 208         case EXPR_POS:
 209                 __split_expr(expr->init_expr);
 210                 break;
 211         case EXPR_SYMBOL:
 212                 __pass_to_client(expr, SYM_HOOK);
 213                 break;
 214         case EXPR_STRING:
 215                 __pass_to_client(expr, STRING_HOOK);
 216                 break;
 217         default:
 218                 break;
 219         };
 220         pop_expression(&big_expression_stack);
 221 }
 222
 223 static int is_forever_loop(struct statement *stmt)
 224 {
 225         struct expression *expr;
 226
 227         expr = strip_expr(stmt->iterator_pre_condition);
 228         if (!expr)
 229                 expr = stmt->iterator_post_condition;
 230         if (!expr) {
 231                 /* this is a for(;;) loop... */
 232                 return 1;
 233         }
 234
 235         if (expr->type == EXPR_VALUE && expr->value == 1)
 236                 return 1;
 237
 238         return 0;
 239 }
 240
 241 static int loop_num;
 242 static char *get_loop_name(int num)
 243 {
 244         char buf[256];
 245
 246         snprintf(buf, 255, "-loop%d", num);
 247         buf[255] = '\0';
 248         return alloc_sname(buf);
 249 }
 250
 251 /*
 252  * Pre Loops are while and for loops.
 253  */
 254 static void handle_pre_loop(struct statement *stmt)
 255 {
 256         int once_through; /* we go through the loop at least once */
 257         struct sm_state *extra_sm = NULL;
 258         int unchanged = 0;
 259         char *loop_name;
 260         struct state_list *slist = NULL;
 261         struct sm_state *sm = NULL;
 262
 263         loop_name = get_loop_name(loop_num);
 264         loop_num++;
 265
 266         __split_stmt(stmt->iterator_pre_statement);
 267
 268         once_through = implied_condition_true(stmt->iterator_pre_condition);
 269
 270         loop_count++;
 271         __push_continues();
 272         __push_breaks();
 273
 274         __merge_gotos(loop_name);
 275
 276         extra_sm = __extra_handle_canonical_loops(stmt, &slist);
 277         __in_pre_condition++;
 278         __pass_to_client(stmt, PRELOOP_HOOK);
 279         __split_whole_condition(stmt->iterator_pre_condition);
 280         __in_pre_condition--;
 281         FOR_EACH_PTR(slist, sm) {
 282                 set_state(sm->owner, sm->name, sm->sym, sm->state);
 283         } END_FOR_EACH_PTR(sm);
 284         free_slist(&slist);
 285         if (extra_sm)
 286                 extra_sm = get_sm_state(extra_sm->owner, extra_sm->name, extra_sm->sym);
 287
 288         if (option_assume_loops)
 289                 once_through = 1;
 290
 291         __split_stmt(stmt->iterator_statement);
 292         __warn_on_silly_pre_loops();
 293         if (is_forever_loop(stmt)) {
 294                 struct state_list *slist;
 295
 296                 __save_gotos(loop_name);
 297
 298                 __push_fake_cur_slist();
 299                 __split_stmt(stmt->iterator_post_statement);
 300                 slist = __pop_fake_cur_slist();
 301
 302                 __discard_continues();
 303                 __discard_false_states();
 304                 __use_breaks();
 305
 306                 if (!__path_is_null())
 307                         __merge_slist_into_cur(slist);
 308                 free_slist(&slist);
 309         } else {
 310                 __merge_continues();
 311                 unchanged = __iterator_unchanged(extra_sm);
 312                 __split_stmt(stmt->iterator_post_statement);
 313                 __save_gotos(loop_name);
 314                 __split_whole_condition(stmt->iterator_pre_condition);
 315                 nullify_path();
 316                 __merge_false_states();
 317                 if (once_through)
 318                         __discard_false_states();
 319                 else
 320                         __merge_false_states();
 321
 322                 if (extra_sm && unchanged)
 323                         __extra_pre_loop_hook_after(extra_sm,
 324                                                 stmt->iterator_post_statement,
 325                                                 stmt->iterator_pre_condition);
 326                 __merge_breaks();
 327         }
 328         loop_count--;
 329 }
 330
 331 /*
 332  * Post loops are do {} while();
 333  */
 334 static void handle_post_loop(struct statement *stmt)
 335 {
 336         char *loop_name;
 337
 338         loop_name = get_loop_name(loop_num);
 339         loop_num++;
 340         loop_count++;
 341
 342         __push_continues();
 343         __push_breaks();
 344         __merge_gotos(loop_name);
 345         __split_stmt(stmt->iterator_statement);
 346         __merge_continues();
 347         if (!is_zero(stmt->iterator_post_condition))
 348                 __save_gotos(loop_name);
 349
 350         if (is_forever_loop(stmt)) {
 351                 __use_breaks();
 352         } else {
 353                 __split_whole_condition(stmt->iterator_post_condition);
 354                 __use_false_states();
 355                 __merge_breaks();
 356         }
 357         loop_count--;
 358 }
 359
 360 static int empty_statement(struct statement *stmt)
 361 {
 362         if (!stmt)
 363                 return 0;
 364         if (stmt->type == STMT_EXPRESSION && !stmt->expression)
 365                 return 1;
 366         return 0;
 367 }
 368
 369 static int last_stmt_on_same_line()
 370 {
 371         struct statement *stmt;
 372         int i = 0;
 373
 374         FOR_EACH_PTR_REVERSE(big_statement_stack, stmt) {
 375                 if (!i++)
 376                         continue;
 377                 if  (stmt->pos.line == get_lineno())
 378                         return 1;
 379                 return 0;
 380         } END_FOR_EACH_PTR_REVERSE(stmt);
 381         return 0;
 382 }
 383
 384 static struct statement *last_stmt;
 385 static int is_last_stmt(struct statement *stmt)
 386 {
 387         if (stmt == last_stmt)
 388                 return 1;
 389         return 0;
 390 }
 391
 392 static void print_unreached_initializers(struct symbol_list *sym_list)
 393 {
 394         struct symbol *sym;
 395
 396         FOR_EACH_PTR(sym_list, sym) {
 397                 if (sym->initializer)
 398                         sm_msg("info: '%s' is not actually initialized (unreached code).",
 399                                 (sym->ident ? sym->ident->name : "this variable"));
 400         } END_FOR_EACH_PTR(sym);
 401 }
 402
 403 static void print_unreached(struct statement *stmt)
 404 {
 405         static int print = 1;
 406
 407         if (!__path_is_null()) {
 408                 print = 1;
 409                 return;
 410         }
 411         if (!print)
 412                 return;
 413
 414         switch (stmt->type) {
 415         case STMT_COMPOUND: /* after a switch before a case stmt */
 416         case STMT_RANGE:
 417         case STMT_CASE:
 418         case STMT_LABEL:
 419                 return;
 420         case STMT_DECLARATION: /* switch (x) { int a; case foo: ... */
 421                 print_unreached_initializers(stmt->declaration);
 422                 return;
 423         case STMT_RETURN: /* gcc complains if you don't have a return statement */
 424                 if (is_last_stmt(stmt))
 425                         return;
 426                 break;
 427         case STMT_GOTO:
 428                 if (!option_spammy)
 429                         return;
 430                 break;
 431         default:
 432                 break;
 433         }
 434         if (!option_spammy && empty_statement(stmt))
 435                 return;
 436         sm_msg("info: ignoring unreachable code.");
 437         print = 0;
 438 }
 439
 440 static void split_asm_constraints(struct expression_list *expr_list)
 441 {
 442         struct expression *expr;
 443         int state = 0;
 444
 445         FOR_EACH_PTR(expr_list, expr) {
 446                 switch (state) {
 447                 case 0: /* identifier */
 448                 case 1: /* constraint */
 449                         state++;
 450                         continue;
 451                 case 2: /* expression */
 452                         state = 0;
 453                         __split_expr(expr);
 454                         continue;
 455                 }
 456         } END_FOR_EACH_PTR(expr);
 457 }
 458
 459 static int is_case_val(struct statement *stmt, long long val)
 460 {
 461         long long case_val;
 462
 463         if (stmt->type != STMT_CASE)
 464                 return 0;
 465         if (!stmt->case_expression) {
 466                 __set_default();
 467                 return 1;
 468         }
 469         if (!get_value(stmt->case_expression, &case_val))
 470                 return 0;
 471         if (case_val == val)
 472                 return 1;
 473         return 0;
 474 }
 475
 476 static void split_known_switch(struct statement *stmt, long long val)
 477 {
 478         struct statement *tmp;
 479
 480         __split_expr(stmt->switch_expression);
 481
 482         push_expression(&switch_expr_stack, stmt->switch_expression);
 483         __save_switch_states(top_expression(switch_expr_stack));
 484         nullify_path();
 485         __push_default();
 486         __push_breaks();
 487
 488         stmt = stmt->switch_statement;
 489
 490         if (!last_stmt)
 491                 last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 492
 493         __push_scope_hooks();
 494         FOR_EACH_PTR(stmt->stmts, tmp) {
 495                 __smatch_lineno = tmp->pos.line;
 496                 if (is_case_val(tmp, val)) {
 497                         __merge_switches(top_expression(switch_expr_stack),
 498                                          stmt->case_expression);
 499                         __pass_case_to_client(top_expression(switch_expr_stack),
 500                                               stmt->case_expression);
 501                 }
 502                 if (__path_is_null())
 503                         continue;
 504                 __split_stmt(tmp);
 505                 if (__path_is_null()) {
 506                         __set_default();
 507                         goto out;
 508                 }
 509         } END_FOR_EACH_PTR(tmp);
 510 out:
 511         __call_scope_hooks();
 512         if (!__pop_default())
 513                 __merge_switches(top_expression(switch_expr_stack),
 514                                  NULL);
 515         __discard_switches();
 516         __merge_breaks();
 517         pop_expression(&switch_expr_stack);
 518 }
 519
 520 void __split_stmt(struct statement *stmt)
 521 {
 522         long long val;
 523
 524         if (!stmt)
 525                 return;
 526
 527         if (out_of_memory() || __bail_on_rest_of_function) {
 528                 static char *printed = NULL;
 529
 530                 if (printed != cur_func)
 531                         sm_msg("Function too hairy.  Giving up.");
 532                 printed = cur_func;
 533                 return;
 534         }
 535
 536         add_ptr_list(&big_statement_stack, stmt);
 537         free_expression_stack(&big_expression_stack);
 538         set_position(stmt->pos);
 539         print_unreached(stmt);
 540         __pass_to_client(stmt, STMT_HOOK);
 541
 542         switch (stmt->type) {
 543         case STMT_DECLARATION:
 544                 split_declaration(stmt->declaration);
 545                 return;
 546         case STMT_RETURN:
 547                 __split_expr(stmt->ret_value);
 548                 __pass_to_client(stmt->ret_value, RETURN_HOOK);
 549                 nullify_path();
 550                 return;
 551         case STMT_EXPRESSION:
 552                 __split_expr(stmt->expression);
 553                 return;
 554         case STMT_COMPOUND: {
 555                 struct statement *tmp;
 556
 557                 if (!last_stmt)
 558                         last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 559                 __push_scope_hooks();
 560                 FOR_EACH_PTR(stmt->stmts, tmp) {
 561                         __split_stmt(tmp);
 562                 } END_FOR_EACH_PTR(tmp);
 563                 __call_scope_hooks();
 564                 return;
 565         }
 566         case STMT_IF:
 567                 if (known_condition_true(stmt->if_conditional)) {
 568                         __split_stmt(stmt->if_true);
 569                         return;
 570                 }
 571                 if (known_condition_false(stmt->if_conditional)) {
 572                         __split_stmt(stmt->if_false);
 573                         return;
 574                 }
 575                 if (option_known_conditions &&
 576                     implied_condition_true(stmt->if_conditional)) {
 577                         sm_info("this condition is true.");
 578                         __split_stmt(stmt->if_true);
 579                         return;
 580                 }
 581                 if (option_known_conditions &&
 582                     implied_condition_false(stmt->if_conditional)) {
 583                         sm_info("this condition is false.");
 584                         __split_stmt(stmt->if_false);
 585                         return;
 586                 }
 587                 __split_whole_condition(stmt->if_conditional);
 588                 __split_stmt(stmt->if_true);
 589                 if (empty_statement(stmt->if_true) &&
 590                         last_stmt_on_same_line() &&
 591                         !get_macro_name(stmt->if_true->pos))
 592                         sm_msg("warn: if();");
 593                 __push_true_states();
 594                 __use_false_states();
 595                 __split_stmt(stmt->if_false);
 596                 __merge_true_states();
 597                 return;
 598         case STMT_ITERATOR:
 599                 if (stmt->iterator_pre_condition)
 600                         handle_pre_loop(stmt);
 601                 else if (stmt->iterator_post_condition)
 602                         handle_post_loop(stmt);
 603                 else {
 604                         // these are for(;;) type loops.
 605                         handle_pre_loop(stmt);
 606                 }
 607                 return;
 608         case STMT_SWITCH:
 609                 if (get_value(stmt->switch_expression, &val)) {
 610                         split_known_switch(stmt, val);
 611                         return;
 612                 }
 613                 __split_expr(stmt->switch_expression);
 614                 push_expression(&switch_expr_stack, stmt->switch_expression);
 615                 __save_switch_states(top_expression(switch_expr_stack));
 616                 nullify_path();
 617                 __push_default();
 618                 __push_breaks();
 619                 __split_stmt(stmt->switch_statement);
 620                 if (!__pop_default())
 621                         __merge_switches(top_expression(switch_expr_stack),
 622                                       NULL);
 623                 __discard_switches();
 624                 __merge_breaks();
 625                 pop_expression(&switch_expr_stack);
 626                 return;
 627         case STMT_CASE:
 628                 __merge_switches(top_expression(switch_expr_stack),
 629                                       stmt->case_expression);
 630                 __pass_case_to_client(top_expression(switch_expr_stack),
 631                                       stmt->case_expression);
 632                 if (!stmt->case_expression)
 633                         __set_default();
 634                 __split_expr(stmt->case_expression);
 635                 __split_expr(stmt->case_to);
 636                 __split_stmt(stmt->case_statement);
 637                 return;
 638         case STMT_LABEL:
 639                 if (stmt->label_identifier &&
 640                     stmt->label_identifier->type == SYM_LABEL &&
 641                     stmt->label_identifier->ident) {
 642                         loop_count = 1000000;
 643                         __merge_gotos(stmt->label_identifier->ident->name);
 644                 }
 645                 __split_stmt(stmt->label_statement);
 646                 return;
 647         case STMT_GOTO:
 648                 __split_expr(stmt->goto_expression);
 649                 if (stmt->goto_label && stmt->goto_label->type == SYM_NODE) {
 650                         if (!strcmp(stmt->goto_label->ident->name, "break")) {
 651                                 __process_breaks();
 652                         } else if (!strcmp(stmt->goto_label->ident->name,
 653                                            "continue")) {
 654                                 __process_continues();
 655                         }
 656                 } else if (stmt->goto_label &&
 657                            stmt->goto_label->type == SYM_LABEL &&
 658                            stmt->goto_label->ident) {
 659                         __save_gotos(stmt->goto_label->ident->name);
 660                 }
 661                 nullify_path();
 662                 return;
 663         case STMT_NONE:
 664                 return;
 665         case STMT_ASM:
 666                 __pass_to_client(stmt, ASM_HOOK);
 667                 __split_expr(stmt->asm_string);
 668                 split_asm_constraints(stmt->asm_outputs);
 669                 split_asm_constraints(stmt->asm_inputs);
 670                 split_asm_constraints(stmt->asm_clobbers);
 671                 return;
 672         case STMT_CONTEXT:
 673                 return;
 674         case STMT_RANGE:
 675                 __split_expr(stmt->range_expression);
 676                 __split_expr(stmt->range_low);
 677                 __split_expr(stmt->range_high);
 678                 return;
 679         }
 680 }
 681
 682 static void split_expr_list(struct expression_list *expr_list)
 683 {
 684         struct expression *expr;
 685
 686         FOR_EACH_PTR(expr_list, expr) {
 687                 __split_expr(expr);
 688         } END_FOR_EACH_PTR(expr);
 689 }
 690
 691 static void split_sym(struct symbol *sym)
 692 {
 693         if (!sym)
 694                 return;
 695         if (!(sym->namespace & NS_SYMBOL))
 696                 return;
 697
 698         __split_stmt(sym->stmt);
 699         __split_expr(sym->array_size);
 700         split_symlist(sym->arguments);
 701         split_symlist(sym->symbol_list);
 702         __split_stmt(sym->inline_stmt);
 703         split_symlist(sym->inline_symbol_list);
 704 }
 705
 706 static void split_symlist(struct symbol_list *sym_list)
 707 {
 708         struct symbol *sym;
 709
 710         FOR_EACH_PTR(sym_list, sym) {
 711                 split_sym(sym);
 712         } END_FOR_EACH_PTR(sym);
 713 }
 714
 715 static struct expression *fake_assign_expr(struct symbol *sym)
 716 {
 717         struct expression *e_assign, *e_symbol;
 718
 719         e_assign = alloc_expression(sym->initializer->pos, EXPR_ASSIGNMENT);
 720         e_symbol = alloc_expression(sym->pos, EXPR_SYMBOL);
 721         e_assign->op = (int)'=';
 722         e_symbol->symbol = sym;
 723         e_symbol->symbol_name = sym->ident;
 724         e_assign->left = e_symbol;
 725         e_assign->right = sym->initializer;
 726         return e_assign;
 727 }
 728
 729 static void do_initializer_stuff(struct symbol *sym)
 730 {
 731         struct expression *assign;
 732
 733         if (!sym->initializer)
 734                 return;
 735         assign = fake_assign_expr(sym);
 736         __split_expr(assign);
 737 }
 738
 739 static void split_declaration(struct symbol_list *sym_list)
 740 {
 741         struct symbol *sym;
 742
 743         FOR_EACH_PTR(sym_list, sym) {
 744                 __pass_to_client(sym, DECLARATION_HOOK);
 745                 do_initializer_stuff(sym);
 746                 split_sym(sym);
 747         } END_FOR_EACH_PTR(sym);
 748 }
 749
 750 static void split_function(struct symbol *sym)
 751 {
 752         struct symbol *base_type = get_base_type(sym);
 753
 754         cur_func_sym = sym;
 755         if (base_type->stmt)
 756                 line_func_start = base_type->stmt->pos.line;
 757         if (sym->ident)
 758                 cur_func = sym->ident->name;
 759         __smatch_lineno = sym->pos.line;
 760         last_stmt = NULL;
 761         loop_count = 0;
 762         sm_debug("new function:  %s\n", cur_func);
 763         if (option_two_passes) {
 764                 __unnullify_path();
 765                 loop_num = 0;
 766                 final_pass = 0;
 767                 __pass_to_client(sym, FUNC_DEF_HOOK);
 768                 __split_stmt(base_type->stmt);
 769                 __split_stmt(base_type->inline_stmt);
 770                 nullify_path();
 771         }
 772         __unnullify_path();
 773         loop_num = 0;
 774         final_pass = 1;
 775         __pass_to_client(sym, FUNC_DEF_HOOK);
 776         __split_stmt(base_type->stmt);
 777         __split_stmt(base_type->inline_stmt);
 778         __pass_to_client(sym, END_FUNC_HOOK);
 779         cur_func = NULL;
 780         line_func_start = 0;
 781         clear_all_states();
 782         free_data_info_allocs();
 783         free_expression_stack(&switch_expr_stack);
 784         __free_ptr_list((struct ptr_list **)&big_statement_stack);
 785         __bail_on_rest_of_function = 0;
 786 }
 787
 788 static struct symbol_list *inlines_called;
 789 static void add_inline_function(struct symbol *sym)
 790 {
 791         static struct symbol_list *already_added;
 792         struct symbol *tmp;
 793
 794         FOR_EACH_PTR(already_added, tmp) {
 795                 if (tmp == sym)
 796                         return;
 797         } END_FOR_EACH_PTR(tmp);
 798
 799         add_ptr_list(&already_added, sym);
 800         add_ptr_list(&inlines_called, sym);
 801 }
 802
 803 static void process_inlines()
 804 {
 805         struct symbol *tmp;
 806
 807         FOR_EACH_PTR(inlines_called, tmp) {
 808                 split_function(tmp);
 809         } END_FOR_EACH_PTR(tmp);
 810         free_ptr_list(&inlines_called);
 811 }
 812
 813 static void split_functions(struct symbol_list *sym_list)
 814 {
 815         struct symbol *sym;
 816
 817         FOR_EACH_PTR(sym_list, sym) {
 818                 set_position(sym->pos);
 819                 if (sym->type == SYM_NODE && get_base_type(sym)->type == SYM_FN) {
 820                         split_function(sym);
 821                         process_inlines();
 822                 } else {
 823                         __pass_to_client(sym, BASE_HOOK);
 824                 }
 825         } END_FOR_EACH_PTR(sym);
 826         __pass_to_client_no_data(END_FILE_HOOK);
 827 }
 828
 829 void smatch(int argc, char **argv)
 830 {
 831
 832         struct string_list *filelist = NULL;
 833         struct symbol_list *sym_list;
 834
 835         if (argc < 2) {
 836                 printf("Usage:  smatch [--debug] <filename.c>\n");
 837                 exit(1);
 838         }
 839         sparse_initialize(argc, argv, &filelist);
 840         FOR_EACH_PTR_NOTAG(filelist, base_file) {
 841                 if (option_file_output) {
 842                         char buf[256];
 843
 844                         snprintf(buf, sizeof(buf), "%s.smatch", base_file);
 845                         sm_outfd = fopen(buf, "w");
 846                         if (!sm_outfd) {
 847                                 printf("Error:  Cannot open %s\n", base_file);
 848                                 exit(1);
 849                         }
 850                 }
 851                 sym_list = sparse_keep_tokens(base_file);
 852                 split_functions(sym_list);
 853         } END_FOR_EACH_PTR_NOTAG(base_file);
 854 }