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 int __inline_call;
  21 int __inline_fn;
  22
  23 static int __smatch_lineno = 0;
  24
  25 static char *base_file;
  26 static const char *filename;
  27 static char *pathname;
  28 static char *full_filename;
  29 static char *cur_func;
  30 static int loop_count;
  31 int __expr_stmt_count;
  32 static struct expression_list *switch_expr_stack = NULL;
  33
  34 struct expression_list *big_expression_stack;
  35 struct statement_list *big_statement_stack;
  36 int __in_pre_condition = 0;
  37 int __bail_on_rest_of_function = 0;
  38 char *get_function(void) { return cur_func; }
  39 int get_lineno(void) { return __smatch_lineno; }
  40 int inside_loop(void) { return !!loop_count; }
  41 struct expression *get_switch_expr(void) { return top_expression(switch_expr_stack); }
  42 int in_expression_statement(void) { return !!__expr_stmt_count; }
  43
  44 static void split_symlist(struct symbol_list *sym_list);
  45 static void split_declaration(struct symbol_list *sym_list);
  46 static void split_expr_list(struct expression_list *expr_list);
  47 static void add_inline_function(struct symbol *sym);
  48 static void parse_inline(struct expression *expr);
  49
  50 int option_assume_loops = 0;
  51 int option_known_conditions = 0;
  52 int option_two_passes = 0;
  53 struct symbol *cur_func_sym = NULL;
  54
  55 const char *get_filename(void)
  56 {
  57         if (option_info)
  58                 return base_file;
  59         if (option_full_path)
  60                 return full_filename;
  61         return filename;
  62 }
  63
  64 static void set_position(struct position pos)
  65 {
  66         int len;
  67         static int prev_stream = -1;
  68
  69         __smatch_lineno = pos.line;
  70
  71         if (pos.stream == prev_stream)
  72                 return;
  73
  74         filename = stream_name(pos.stream);
  75
  76         free(full_filename);
  77         pathname = getcwd(NULL, 0);
  78         if (pathname) {
  79                 len = strlen(pathname) + 1 + strlen(filename) + 1;
  80                 full_filename = malloc(len);
  81                 snprintf(full_filename, len, "%s/%s", pathname, filename);
  82         } else {
  83                 full_filename = alloc_string(filename);
  84         }
  85         free(pathname);
  86 }
  87
  88 static int is_inline_func(struct expression *expr)
  89 {
  90         if (expr->type != EXPR_SYMBOL || !expr->symbol)
  91                 return 0;
  92         if (expr->symbol->ctype.modifiers & MOD_INLINE)
  93                 return 1;
  94         return 0;
  95 }
  96
  97 static int is_noreturn_func(struct expression *expr)
  98 {
  99         if (expr->type != EXPR_SYMBOL || !expr->symbol)
 100                 return 0;
 101         if (expr->symbol->ctype.modifiers & MOD_NORETURN)
 102                 return 1;
 103         return 0;
 104 }
 105
 106 static int should_inline(struct expression *expr)
 107 {
 108         struct symbol *sym;
 109
 110         if (__inline_fn)  /* don't nest */
 111                 return 0;
 112
 113         if (expr->type != EXPR_SYMBOL || !expr->symbol)
 114                 return 0;
 115         sym = get_base_type(expr->symbol);
 116         if (sym->stmt && sym->stmt->type == STMT_COMPOUND) {
 117                 if (ptr_list_size((struct ptr_list *)sym->stmt->stmts) <= 10)
 118                         return 1;
 119                 return 0;
 120         }
 121         if (sym->inline_stmt && sym->inline_stmt->type == STMT_COMPOUND) {
 122                 if (ptr_list_size((struct ptr_list *)sym->inline_stmt->stmts) <= 10)
 123                         return 1;
 124                 return 0;
 125         }
 126         return 0;
 127 }
 128
 129 void __split_expr(struct expression *expr)
 130 {
 131         if (!expr)
 132                 return;
 133
 134         // sm_msg(" Debug expr_type %d %s", expr->type, show_special(expr->op));
 135
 136         push_expression(&big_expression_stack, expr);
 137         set_position(expr->pos);
 138         __pass_to_client(expr, EXPR_HOOK);
 139
 140         switch (expr->type) {
 141         case EXPR_PREOP:
 142                 if (expr->op == '*')
 143                         __pass_to_client(expr, DEREF_HOOK);
 144         case EXPR_POSTOP:
 145                 __pass_to_client(expr, OP_HOOK);
 146                 __split_expr(expr->unop);
 147                 break;
 148         case EXPR_STATEMENT:
 149                 __expr_stmt_count++;
 150                 __split_stmt(expr->statement);
 151                 __expr_stmt_count--;
 152                 break;
 153         case EXPR_LOGICAL:
 154         case EXPR_COMPARE:
 155                 __pass_to_client(expr, LOGIC_HOOK);
 156                 __handle_logic(expr);
 157                 break;
 158         case EXPR_BINOP:
 159                 __pass_to_client(expr, BINOP_HOOK);
 160         case EXPR_COMMA:
 161                 __split_expr(expr->left);
 162                 __split_expr(expr->right);
 163                 break;
 164         case EXPR_ASSIGNMENT: {
 165                 struct expression *tmp;
 166
 167                 if (!expr->right)
 168                         break;
 169
 170                 __pass_to_client(expr, RAW_ASSIGNMENT_HOOK);
 171
 172                 /* foo = !bar() */
 173                 if (__handle_condition_assigns(expr))
 174                         break;
 175                 /* foo = (x < 5 ? foo : 5); */
 176                 if (__handle_select_assigns(expr))
 177                         break;
 178                 /* foo = ({frob(); frob(); frob(); 1;}) */
 179                 if (__handle_expr_statement_assigns(expr))
 180                         break;
 181
 182                 __split_expr(expr->right);
 183                 __pass_to_client(expr, ASSIGNMENT_HOOK);
 184                 tmp = strip_expr(expr->right);
 185                 if (tmp->type == EXPR_CALL)
 186                         __pass_to_client(expr, CALL_ASSIGNMENT_HOOK);
 187                 if (get_macro_name(tmp->pos) &&
 188                     get_macro_name(expr->pos) != get_macro_name(tmp->pos))
 189                         __pass_to_client(expr, MACRO_ASSIGNMENT_HOOK);
 190                 __split_expr(expr->left);
 191                 break;
 192         }
 193         case EXPR_DEREF:
 194                 __pass_to_client(expr, DEREF_HOOK);
 195                 __split_expr(expr->deref);
 196                 break;
 197         case EXPR_SLICE:
 198                 __split_expr(expr->base);
 199                 break;
 200         case EXPR_CAST:
 201         case EXPR_FORCE_CAST:
 202                 __pass_to_client(expr, CAST_HOOK);
 203                 __split_expr(expr->cast_expression);
 204                 break;
 205         case EXPR_SIZEOF:
 206                 if (expr->cast_expression)
 207                         __pass_to_client(strip_parens(expr->cast_expression),
 208                                          SIZEOF_HOOK);
 209                 break;
 210         case EXPR_OFFSETOF:
 211         case EXPR_ALIGNOF:
 212                 evaluate_expression(expr);
 213                 break;
 214         case EXPR_CONDITIONAL:
 215         case EXPR_SELECT:
 216                 if (known_condition_true(expr->conditional)) {
 217                         __split_expr(expr->cond_true);
 218                         break;
 219                 }
 220                 if (known_condition_false(expr->conditional)) {
 221                         __split_expr(expr->cond_false);
 222                         break;
 223                 }
 224                 __pass_to_client(expr, SELECT_HOOK);
 225                 __split_whole_condition(expr->conditional);
 226                 __split_expr(expr->cond_true);
 227                 __push_true_states();
 228                 __use_false_states();
 229                 __split_expr(expr->cond_false);
 230                 __merge_true_states();
 231                 break;
 232         case EXPR_CALL:
 233                 if (sym_name_is("__builtin_constant_p", expr->fn))
 234                         break;
 235                 split_expr_list(expr->args);
 236                 __split_expr(expr->fn);
 237                 if (is_inline_func(expr->fn))
 238                         add_inline_function(expr->fn->symbol);
 239                 if (should_inline(expr->fn))
 240                         __inline_call = 1;
 241                 __pass_to_client(expr, FUNCTION_CALL_HOOK);
 242                 __inline_call = 0;
 243                 if (should_inline(expr->fn)) {
 244                         parse_inline(expr->fn);
 245                 }
 246                 if (is_noreturn_func(expr->fn))
 247                         nullify_path();
 248                 break;
 249         case EXPR_INITIALIZER:
 250                 split_expr_list(expr->expr_list);
 251                 break;
 252         case EXPR_IDENTIFIER:
 253                 __split_expr(expr->ident_expression);
 254                 break;
 255         case EXPR_INDEX:
 256                 __split_expr(expr->idx_expression);
 257                 break;
 258         case EXPR_POS:
 259                 __split_expr(expr->init_expr);
 260                 break;
 261         case EXPR_SYMBOL:
 262                 __pass_to_client(expr, SYM_HOOK);
 263                 break;
 264         case EXPR_STRING:
 265                 __pass_to_client(expr, STRING_HOOK);
 266                 break;
 267         default:
 268                 break;
 269         };
 270         pop_expression(&big_expression_stack);
 271 }
 272
 273 static int is_forever_loop(struct statement *stmt)
 274 {
 275         struct expression *expr;
 276
 277         expr = strip_expr(stmt->iterator_pre_condition);
 278         if (!expr)
 279                 expr = stmt->iterator_post_condition;
 280         if (!expr) {
 281                 /* this is a for(;;) loop... */
 282                 return 1;
 283         }
 284
 285         if (expr->type == EXPR_VALUE && expr->value == 1)
 286                 return 1;
 287
 288         return 0;
 289 }
 290
 291 static int loop_num;
 292 static char *get_loop_name(int num)
 293 {
 294         char buf[256];
 295
 296         snprintf(buf, 255, "-loop%d", num);
 297         buf[255] = '\0';
 298         return alloc_sname(buf);
 299 }
 300
 301 /*
 302  * Pre Loops are while and for loops.
 303  */
 304 static void handle_pre_loop(struct statement *stmt)
 305 {
 306         int once_through; /* we go through the loop at least once */
 307         struct sm_state *extra_sm = NULL;
 308         int unchanged = 0;
 309         char *loop_name;
 310         struct state_list *slist = NULL;
 311         struct sm_state *sm = NULL;
 312
 313         loop_name = get_loop_name(loop_num);
 314         loop_num++;
 315
 316         __split_stmt(stmt->iterator_pre_statement);
 317
 318         once_through = implied_condition_true(stmt->iterator_pre_condition);
 319
 320         loop_count++;
 321         __push_continues();
 322         __push_breaks();
 323
 324         __merge_gotos(loop_name);
 325
 326         extra_sm = __extra_handle_canonical_loops(stmt, &slist);
 327         __in_pre_condition++;
 328         __pass_to_client(stmt, PRELOOP_HOOK);
 329         __split_whole_condition(stmt->iterator_pre_condition);
 330         __in_pre_condition--;
 331         FOR_EACH_PTR(slist, sm) {
 332                 set_state(sm->owner, sm->name, sm->sym, sm->state);
 333         } END_FOR_EACH_PTR(sm);
 334         free_slist(&slist);
 335         if (extra_sm)
 336                 extra_sm = get_sm_state(extra_sm->owner, extra_sm->name, extra_sm->sym);
 337
 338         if (option_assume_loops)
 339                 once_through = 1;
 340
 341         __split_stmt(stmt->iterator_statement);
 342         __warn_on_silly_pre_loops();
 343         if (is_forever_loop(stmt)) {
 344                 struct state_list *slist;
 345
 346                 __save_gotos(loop_name);
 347
 348                 __push_fake_cur_slist();
 349                 __split_stmt(stmt->iterator_post_statement);
 350                 slist = __pop_fake_cur_slist();
 351
 352                 __discard_continues();
 353                 __discard_false_states();
 354                 __use_breaks();
 355
 356                 if (!__path_is_null())
 357                         __merge_slist_into_cur(slist);
 358                 free_slist(&slist);
 359         } else {
 360                 __merge_continues();
 361                 unchanged = __iterator_unchanged(extra_sm);
 362                 __split_stmt(stmt->iterator_post_statement);
 363                 __save_gotos(loop_name);
 364                 __split_whole_condition(stmt->iterator_pre_condition);
 365                 nullify_path();
 366                 __merge_false_states();
 367                 if (once_through)
 368                         __discard_false_states();
 369                 else
 370                         __merge_false_states();
 371
 372                 if (extra_sm && unchanged)
 373                         __extra_pre_loop_hook_after(extra_sm,
 374                                                 stmt->iterator_post_statement,
 375                                                 stmt->iterator_pre_condition);
 376                 __merge_breaks();
 377         }
 378         loop_count--;
 379 }
 380
 381 /*
 382  * Post loops are do {} while();
 383  */
 384 static void handle_post_loop(struct statement *stmt)
 385 {
 386         char *loop_name;
 387
 388         loop_name = get_loop_name(loop_num);
 389         loop_num++;
 390         loop_count++;
 391
 392         __push_continues();
 393         __push_breaks();
 394         __merge_gotos(loop_name);
 395         __split_stmt(stmt->iterator_statement);
 396         __merge_continues();
 397         if (!is_zero(stmt->iterator_post_condition))
 398                 __save_gotos(loop_name);
 399
 400         if (is_forever_loop(stmt)) {
 401                 __use_breaks();
 402         } else {
 403                 __split_whole_condition(stmt->iterator_post_condition);
 404                 __use_false_states();
 405                 __merge_breaks();
 406         }
 407         loop_count--;
 408 }
 409
 410 static int empty_statement(struct statement *stmt)
 411 {
 412         if (!stmt)
 413                 return 0;
 414         if (stmt->type == STMT_EXPRESSION && !stmt->expression)
 415                 return 1;
 416         return 0;
 417 }
 418
 419 static int last_stmt_on_same_line()
 420 {
 421         struct statement *stmt;
 422         int i = 0;
 423
 424         FOR_EACH_PTR_REVERSE(big_statement_stack, stmt) {
 425                 if (!i++)
 426                         continue;
 427                 if  (stmt->pos.line == get_lineno())
 428                         return 1;
 429                 return 0;
 430         } END_FOR_EACH_PTR_REVERSE(stmt);
 431         return 0;
 432 }
 433
 434 static struct statement *last_stmt;
 435 static int is_last_stmt(struct statement *stmt)
 436 {
 437         if (stmt == last_stmt)
 438                 return 1;
 439         return 0;
 440 }
 441
 442 static void print_unreached_initializers(struct symbol_list *sym_list)
 443 {
 444         struct symbol *sym;
 445
 446         FOR_EACH_PTR(sym_list, sym) {
 447                 if (sym->initializer)
 448                         sm_msg("info: '%s' is not actually initialized (unreached code).",
 449                                 (sym->ident ? sym->ident->name : "this variable"));
 450         } END_FOR_EACH_PTR(sym);
 451 }
 452
 453 static void print_unreached(struct statement *stmt)
 454 {
 455         static int print = 1;
 456
 457         if (!__path_is_null()) {
 458                 print = 1;
 459                 return;
 460         }
 461         if (!print)
 462                 return;
 463
 464         switch (stmt->type) {
 465         case STMT_COMPOUND: /* after a switch before a case stmt */
 466         case STMT_RANGE:
 467         case STMT_CASE:
 468         case STMT_LABEL:
 469                 return;
 470         case STMT_DECLARATION: /* switch (x) { int a; case foo: ... */
 471                 print_unreached_initializers(stmt->declaration);
 472                 return;
 473         case STMT_RETURN: /* gcc complains if you don't have a return statement */
 474                 if (is_last_stmt(stmt))
 475                         return;
 476                 break;
 477         case STMT_GOTO:
 478                 if (!option_spammy)
 479                         return;
 480                 break;
 481         default:
 482                 break;
 483         }
 484         if (!option_spammy && empty_statement(stmt))
 485                 return;
 486         sm_msg("info: ignoring unreachable code.");
 487         print = 0;
 488 }
 489
 490 static void split_asm_constraints(struct expression_list *expr_list)
 491 {
 492         struct expression *expr;
 493         int state = 0;
 494
 495         FOR_EACH_PTR(expr_list, expr) {
 496                 switch (state) {
 497                 case 0: /* identifier */
 498                 case 1: /* constraint */
 499                         state++;
 500                         continue;
 501                 case 2: /* expression */
 502                         state = 0;
 503                         __split_expr(expr);
 504                         continue;
 505                 }
 506         } END_FOR_EACH_PTR(expr);
 507 }
 508
 509 static int is_case_val(struct statement *stmt, sval_t sval)
 510 {
 511         sval_t case_sval;
 512
 513         if (stmt->type != STMT_CASE)
 514                 return 0;
 515         if (!stmt->case_expression) {
 516                 __set_default();
 517                 return 1;
 518         }
 519         if (!get_value(stmt->case_expression, &case_sval))
 520                 return 0;
 521         if (case_sval.value == sval.value)
 522                 return 1;
 523         return 0;
 524 }
 525
 526 static void split_known_switch(struct statement *stmt, sval_t sval)
 527 {
 528         struct statement *tmp;
 529
 530         __split_expr(stmt->switch_expression);
 531
 532         push_expression(&switch_expr_stack, stmt->switch_expression);
 533         __save_switch_states(top_expression(switch_expr_stack));
 534         nullify_path();
 535         __push_default();
 536         __push_breaks();
 537
 538         stmt = stmt->switch_statement;
 539
 540         if (!last_stmt)
 541                 last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 542
 543         __push_scope_hooks();
 544         FOR_EACH_PTR(stmt->stmts, tmp) {
 545                 __smatch_lineno = tmp->pos.line;
 546                 if (is_case_val(tmp, sval)) {
 547                         __merge_switches(top_expression(switch_expr_stack),
 548                                          stmt->case_expression);
 549                         __pass_case_to_client(top_expression(switch_expr_stack),
 550                                               stmt->case_expression);
 551                 }
 552                 if (__path_is_null())
 553                         continue;
 554                 __split_stmt(tmp);
 555                 if (__path_is_null()) {
 556                         __set_default();
 557                         goto out;
 558                 }
 559         } END_FOR_EACH_PTR(tmp);
 560 out:
 561         __call_scope_hooks();
 562         if (!__pop_default())
 563                 __merge_switches(top_expression(switch_expr_stack),
 564                                  NULL);
 565         __discard_switches();
 566         __merge_breaks();
 567         pop_expression(&switch_expr_stack);
 568 }
 569
 570 void __split_stmt(struct statement *stmt)
 571 {
 572         sval_t sval;
 573
 574         if (!stmt)
 575                 return;
 576
 577         if (out_of_memory() || __bail_on_rest_of_function) {
 578                 static char *printed = NULL;
 579
 580                 if (printed != cur_func)
 581                         sm_msg("Function too hairy.  Giving up.");
 582                 final_pass = 0;  /* turn off sm_msg() from here */
 583                 printed = cur_func;
 584                 return;
 585         }
 586
 587         add_ptr_list(&big_statement_stack, stmt);
 588         free_expression_stack(&big_expression_stack);
 589         set_position(stmt->pos);
 590         print_unreached(stmt);
 591         __pass_to_client(stmt, STMT_HOOK);
 592
 593         switch (stmt->type) {
 594         case STMT_DECLARATION:
 595                 split_declaration(stmt->declaration);
 596                 return;
 597         case STMT_RETURN:
 598                 __split_expr(stmt->ret_value);
 599                 __pass_to_client(stmt->ret_value, RETURN_HOOK);
 600                 nullify_path();
 601                 return;
 602         case STMT_EXPRESSION:
 603                 __split_expr(stmt->expression);
 604                 return;
 605         case STMT_COMPOUND: {
 606                 struct statement *tmp;
 607
 608                 if (!last_stmt)
 609                         last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 610                 __push_scope_hooks();
 611                 FOR_EACH_PTR(stmt->stmts, tmp) {
 612                         __split_stmt(tmp);
 613                 } END_FOR_EACH_PTR(tmp);
 614                 __call_scope_hooks();
 615                 return;
 616         }
 617         case STMT_IF:
 618                 if (known_condition_true(stmt->if_conditional)) {
 619                         __split_stmt(stmt->if_true);
 620                         return;
 621                 }
 622                 if (known_condition_false(stmt->if_conditional)) {
 623                         __split_stmt(stmt->if_false);
 624                         return;
 625                 }
 626                 if (option_known_conditions &&
 627                     implied_condition_true(stmt->if_conditional)) {
 628                         sm_info("this condition is true.");
 629                         __split_stmt(stmt->if_true);
 630                         return;
 631                 }
 632                 if (option_known_conditions &&
 633                     implied_condition_false(stmt->if_conditional)) {
 634                         sm_info("this condition is false.");
 635                         __split_stmt(stmt->if_false);
 636                         return;
 637                 }
 638                 __split_whole_condition(stmt->if_conditional);
 639                 __split_stmt(stmt->if_true);
 640                 if (empty_statement(stmt->if_true) &&
 641                         last_stmt_on_same_line() &&
 642                         !get_macro_name(stmt->if_true->pos))
 643                         sm_msg("warn: if();");
 644                 __push_true_states();
 645                 __use_false_states();
 646                 __split_stmt(stmt->if_false);
 647                 __merge_true_states();
 648                 return;
 649         case STMT_ITERATOR:
 650                 if (stmt->iterator_pre_condition)
 651                         handle_pre_loop(stmt);
 652                 else if (stmt->iterator_post_condition)
 653                         handle_post_loop(stmt);
 654                 else {
 655                         // these are for(;;) type loops.
 656                         handle_pre_loop(stmt);
 657                 }
 658                 return;
 659         case STMT_SWITCH:
 660                 if (get_value(stmt->switch_expression, &sval)) {
 661                         split_known_switch(stmt, sval);
 662                         return;
 663                 }
 664                 __split_expr(stmt->switch_expression);
 665                 push_expression(&switch_expr_stack, stmt->switch_expression);
 666                 __save_switch_states(top_expression(switch_expr_stack));
 667                 nullify_path();
 668                 __push_default();
 669                 __push_breaks();
 670                 __split_stmt(stmt->switch_statement);
 671                 if (!__pop_default())
 672                         __merge_switches(top_expression(switch_expr_stack),
 673                                       NULL);
 674                 __discard_switches();
 675                 __merge_breaks();
 676                 pop_expression(&switch_expr_stack);
 677                 return;
 678         case STMT_CASE:
 679                 __merge_switches(top_expression(switch_expr_stack),
 680                                       stmt->case_expression);
 681                 __pass_case_to_client(top_expression(switch_expr_stack),
 682                                       stmt->case_expression);
 683                 if (!stmt->case_expression)
 684                         __set_default();
 685                 __split_expr(stmt->case_expression);
 686                 __split_expr(stmt->case_to);
 687                 __split_stmt(stmt->case_statement);
 688                 return;
 689         case STMT_LABEL:
 690                 if (stmt->label_identifier &&
 691                     stmt->label_identifier->type == SYM_LABEL &&
 692                     stmt->label_identifier->ident) {
 693                         loop_count = 1000000;
 694                         __merge_gotos(stmt->label_identifier->ident->name);
 695                 }
 696                 __split_stmt(stmt->label_statement);
 697                 return;
 698         case STMT_GOTO:
 699                 __split_expr(stmt->goto_expression);
 700                 if (stmt->goto_label && stmt->goto_label->type == SYM_NODE) {
 701                         if (!strcmp(stmt->goto_label->ident->name, "break")) {
 702                                 __process_breaks();
 703                         } else if (!strcmp(stmt->goto_label->ident->name,
 704                                            "continue")) {
 705                                 __process_continues();
 706                         }
 707                 } else if (stmt->goto_label &&
 708                            stmt->goto_label->type == SYM_LABEL &&
 709                            stmt->goto_label->ident) {
 710                         __save_gotos(stmt->goto_label->ident->name);
 711                 }
 712                 nullify_path();
 713                 return;
 714         case STMT_NONE:
 715                 return;
 716         case STMT_ASM:
 717                 __pass_to_client(stmt, ASM_HOOK);
 718                 __split_expr(stmt->asm_string);
 719                 split_asm_constraints(stmt->asm_outputs);
 720                 split_asm_constraints(stmt->asm_inputs);
 721                 split_asm_constraints(stmt->asm_clobbers);
 722                 return;
 723         case STMT_CONTEXT:
 724                 return;
 725         case STMT_RANGE:
 726                 __split_expr(stmt->range_expression);
 727                 __split_expr(stmt->range_low);
 728                 __split_expr(stmt->range_high);
 729                 return;
 730         }
 731 }
 732
 733 static void split_expr_list(struct expression_list *expr_list)
 734 {
 735         struct expression *expr;
 736
 737         FOR_EACH_PTR(expr_list, expr) {
 738                 __split_expr(expr);
 739         } END_FOR_EACH_PTR(expr);
 740 }
 741
 742 static void split_sym(struct symbol *sym)
 743 {
 744         if (!sym)
 745                 return;
 746         if (!(sym->namespace & NS_SYMBOL))
 747                 return;
 748
 749         __split_stmt(sym->stmt);
 750         __split_expr(sym->array_size);
 751         split_symlist(sym->arguments);
 752         split_symlist(sym->symbol_list);
 753         __split_stmt(sym->inline_stmt);
 754         split_symlist(sym->inline_symbol_list);
 755 }
 756
 757 static void split_symlist(struct symbol_list *sym_list)
 758 {
 759         struct symbol *sym;
 760
 761         FOR_EACH_PTR(sym_list, sym) {
 762                 split_sym(sym);
 763         } END_FOR_EACH_PTR(sym);
 764 }
 765
 766 static void fake_member_assigns(struct symbol *sym)
 767 {
 768         struct expression *symbol, *deref, *assign, *tmp;
 769
 770         symbol = symbol_expression(sym);
 771         FOR_EACH_PTR(sym->initializer->expr_list, tmp) {
 772                 if (tmp->type != EXPR_IDENTIFIER) /* how to handle arrays?? */
 773                         continue;
 774                 deref = member_expression(symbol, '.', tmp->expr_ident);
 775                 assign = assign_expression(deref, tmp->ident_expression);
 776                 __split_expr(assign);
 777         } END_FOR_EACH_PTR(tmp);
 778 }
 779
 780 static void fake_assign_expr(struct symbol *sym)
 781 {
 782         struct expression *assign, *symbol;
 783
 784         symbol = symbol_expression(sym);
 785         assign = assign_expression(symbol, sym->initializer);
 786         __split_expr(assign);
 787 }
 788
 789 static void do_initializer_stuff(struct symbol *sym)
 790 {
 791         if (!sym->initializer)
 792                 return;
 793         if (sym->initializer->type == EXPR_INITIALIZER)
 794                 fake_member_assigns(sym);
 795         else
 796                 fake_assign_expr(sym);
 797 }
 798
 799 static void split_declaration(struct symbol_list *sym_list)
 800 {
 801         struct symbol *sym;
 802
 803         FOR_EACH_PTR(sym_list, sym) {
 804                 __pass_to_client(sym, DECLARATION_HOOK);
 805                 do_initializer_stuff(sym);
 806                 split_sym(sym);
 807         } END_FOR_EACH_PTR(sym);
 808 }
 809
 810 static void fake_global_assign(struct symbol *sym)
 811 {
 812         struct expression *assign, *symbol;
 813
 814         if (!sym->initializer)
 815                 return;
 816         if (sym->initializer->type == EXPR_INITIALIZER) {
 817                 struct expression *deref, *tmp;
 818
 819                 symbol = symbol_expression(sym);
 820                 FOR_EACH_PTR(sym->initializer->expr_list, tmp) {
 821                         if (tmp->type != EXPR_IDENTIFIER) /* how to handle arrays?? */
 822                                 continue;
 823                         deref = member_expression(symbol, '.', tmp->expr_ident);
 824                         assign = assign_expression(deref, tmp->ident_expression);
 825                         __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
 826                 } END_FOR_EACH_PTR(tmp);
 827         } else {
 828                 symbol = symbol_expression(sym);
 829                 assign = assign_expression(symbol, sym->initializer);
 830                 __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
 831         }
 832 }
 833
 834 static void split_function(struct symbol *sym)
 835 {
 836         struct symbol *base_type = get_base_type(sym);
 837
 838         cur_func_sym = sym;
 839         if (sym->ident)
 840                 cur_func = sym->ident->name;
 841         __smatch_lineno = sym->pos.line;
 842         last_stmt = NULL;
 843         loop_count = 0;
 844         sm_debug("new function:  %s\n", cur_func);
 845         __slist_id = 0;
 846         if (option_two_passes) {
 847                 __unnullify_path();
 848                 loop_num = 0;
 849                 final_pass = 0;
 850                 __pass_to_client(sym, FUNC_DEF_HOOK);
 851                 __pass_to_client(sym, AFTER_DEF_HOOK);
 852                 __split_stmt(base_type->stmt);
 853                 __split_stmt(base_type->inline_stmt);
 854                 nullify_path();
 855         }
 856         __unnullify_path();
 857         loop_num = 0;
 858         final_pass = 1;
 859         __pass_to_client(sym, FUNC_DEF_HOOK);
 860         __pass_to_client(sym, AFTER_DEF_HOOK);
 861         __split_stmt(base_type->stmt);
 862         __split_stmt(base_type->inline_stmt);
 863         __pass_to_client(sym, END_FUNC_HOOK);
 864         cur_func = NULL;
 865         clear_all_states();
 866         free_data_info_allocs();
 867         free_expression_stack(&switch_expr_stack);
 868         __free_ptr_list((struct ptr_list **)&big_statement_stack);
 869         __bail_on_rest_of_function = 0;
 870 }
 871
 872 static void parse_inline(struct expression *expr)
 873 {
 874         struct symbol *base_type;
 875         int loop_num_bak = loop_num;
 876         int final_pass_bak = final_pass;
 877         char *cur_func_bak = cur_func;
 878         struct statement_list *big_statement_stack_bak = big_statement_stack;
 879         struct expression_list *switch_expr_stack_bak = switch_expr_stack;
 880         struct symbol *cur_func_sym_bak = cur_func_sym;
 881
 882         sm_debug("inline function:  %s\n", cur_func);
 883         final_pass = 0;  /* don't print anything */
 884         __inline_fn = 1;
 885
 886         base_type = get_base_type(expr->symbol);
 887         cur_func_sym = expr->symbol;
 888         if (expr->symbol->ident)
 889                 cur_func = expr->symbol->ident->name;
 890         else
 891                 cur_func = NULL;
 892         set_position(expr->symbol->pos);
 893
 894         save_all_states();
 895         nullify_all_states();
 896         big_statement_stack = NULL;
 897         switch_expr_stack = NULL;
 898
 899         __unnullify_path();
 900         loop_num = 0;
 901         __pass_to_client(expr->symbol, FUNC_DEF_HOOK);
 902         __pass_to_client(expr->symbol, AFTER_DEF_HOOK);
 903         __split_stmt(base_type->stmt);
 904         __split_stmt(base_type->inline_stmt);
 905         __pass_to_client(expr->symbol, END_FUNC_HOOK);
 906
 907         free_expression_stack(&switch_expr_stack);
 908         __free_ptr_list((struct ptr_list **)&big_statement_stack);
 909         nullify_path();
 910
 911         loop_num = loop_num_bak;
 912         final_pass = final_pass_bak;
 913         cur_func_sym = cur_func_sym_bak;
 914         cur_func = cur_func_bak;
 915         big_statement_stack = big_statement_stack_bak;
 916         switch_expr_stack = switch_expr_stack_bak;
 917
 918         restore_all_states();
 919         set_position(expr->pos);
 920         __inline_fn = 0;
 921 }
 922
 923 static struct symbol_list *inlines_called;
 924 static void add_inline_function(struct symbol *sym)
 925 {
 926         static struct symbol_list *already_added;
 927         struct symbol *tmp;
 928
 929         FOR_EACH_PTR(already_added, tmp) {
 930                 if (tmp == sym)
 931                         return;
 932         } END_FOR_EACH_PTR(tmp);
 933
 934         add_ptr_list(&already_added, sym);
 935         add_ptr_list(&inlines_called, sym);
 936 }
 937
 938 static void process_inlines()
 939 {
 940         struct symbol *tmp;
 941
 942         FOR_EACH_PTR(inlines_called, tmp) {
 943                 split_function(tmp);
 944         } END_FOR_EACH_PTR(tmp);
 945         free_ptr_list(&inlines_called);
 946 }
 947
 948 static void split_functions(struct symbol_list *sym_list)
 949 {
 950         struct symbol *sym;
 951
 952         FOR_EACH_PTR(sym_list, sym) {
 953                 set_position(sym->pos);
 954                 if (sym->type == SYM_NODE && get_base_type(sym)->type == SYM_FN) {
 955                         split_function(sym);
 956                         process_inlines();
 957                 } else {
 958                         __pass_to_client(sym, BASE_HOOK);
 959                         fake_global_assign(sym);
 960                 }
 961         } END_FOR_EACH_PTR(sym);
 962         __pass_to_client_no_data(END_FILE_HOOK);
 963 }
 964
 965 void smatch(int argc, char **argv)
 966 {
 967
 968         struct string_list *filelist = NULL;
 969         struct symbol_list *sym_list;
 970
 971         if (argc < 2) {
 972                 printf("Usage:  smatch [--debug] <filename.c>\n");
 973                 exit(1);
 974         }
 975         sparse_initialize(argc, argv, &filelist);
 976         FOR_EACH_PTR_NOTAG(filelist, base_file) {
 977                 if (option_file_output) {
 978                         char buf[256];
 979
 980                         snprintf(buf, sizeof(buf), "%s.smatch", base_file);
 981                         sm_outfd = fopen(buf, "w");
 982                         if (!sm_outfd) {
 983                                 printf("Error:  Cannot open %s\n", base_file);
 984                                 exit(1);
 985                         }
 986                 }
 987                 sym_list = sparse_keep_tokens(base_file);
 988                 split_functions(sym_list);
 989         } END_FOR_EACH_PTR_NOTAG(base_file);
 990 }