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 struct expression  *__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 const char *get_base_file(void)
  65 {
  66         return base_file;
  67 }
  68
  69 static void set_position(struct position pos)
  70 {
  71         int len;
  72         static int prev_stream = -1;
  73
  74         __smatch_lineno = pos.line;
  75
  76         if (pos.stream == prev_stream)
  77                 return;
  78
  79         filename = stream_name(pos.stream);
  80
  81         free(full_filename);
  82         pathname = getcwd(NULL, 0);
  83         if (pathname) {
  84                 len = strlen(pathname) + 1 + strlen(filename) + 1;
  85                 full_filename = malloc(len);
  86                 snprintf(full_filename, len, "%s/%s", pathname, filename);
  87         } else {
  88                 full_filename = alloc_string(filename);
  89         }
  90         free(pathname);
  91 }
  92
  93 static int is_inline_func(struct expression *expr)
  94 {
  95         if (expr->type != EXPR_SYMBOL || !expr->symbol)
  96                 return 0;
  97         if (expr->symbol->ctype.modifiers & MOD_INLINE)
  98                 return 1;
  99         return 0;
 100 }
 101
 102 static int is_noreturn_func(struct expression *expr)
 103 {
 104         if (expr->type != EXPR_SYMBOL || !expr->symbol)
 105                 return 0;
 106         if (expr->symbol->ctype.modifiers & MOD_NORETURN)
 107                 return 1;
 108         return 0;
 109 }
 110
 111 int inlinable(struct expression *expr)
 112 {
 113         struct symbol *sym;
 114
 115         if (__inline_fn)  /* don't nest */
 116                 return 0;
 117
 118         if (expr->type != EXPR_SYMBOL || !expr->symbol)
 119                 return 0;
 120         sym = get_base_type(expr->symbol);
 121         if (sym->stmt && sym->stmt->type == STMT_COMPOUND) {
 122                 if (ptr_list_size((struct ptr_list *)sym->stmt->stmts) <= 10)
 123                         return 1;
 124                 return 0;
 125         }
 126         if (sym->inline_stmt && sym->inline_stmt->type == STMT_COMPOUND) {
 127                 if (ptr_list_size((struct ptr_list *)sym->inline_stmt->stmts) <= 10)
 128                         return 1;
 129                 return 0;
 130         }
 131         return 0;
 132 }
 133
 134 void __split_expr(struct expression *expr)
 135 {
 136         if (!expr)
 137                 return;
 138
 139         // sm_msg(" Debug expr_type %d %s", expr->type, show_special(expr->op));
 140
 141         push_expression(&big_expression_stack, expr);
 142         set_position(expr->pos);
 143         __pass_to_client(expr, EXPR_HOOK);
 144
 145         switch (expr->type) {
 146         case EXPR_PREOP:
 147                 if (expr->op == '*')
 148                         __pass_to_client(expr, DEREF_HOOK);
 149         case EXPR_POSTOP:
 150                 __pass_to_client(expr, OP_HOOK);
 151                 __split_expr(expr->unop);
 152                 break;
 153         case EXPR_STATEMENT:
 154                 __expr_stmt_count++;
 155                 __split_stmt(expr->statement);
 156                 __expr_stmt_count--;
 157                 break;
 158         case EXPR_LOGICAL:
 159         case EXPR_COMPARE:
 160                 __pass_to_client(expr, LOGIC_HOOK);
 161                 __handle_logic(expr);
 162                 break;
 163         case EXPR_BINOP:
 164                 __pass_to_client(expr, BINOP_HOOK);
 165         case EXPR_COMMA:
 166                 __split_expr(expr->left);
 167                 __split_expr(expr->right);
 168                 break;
 169         case EXPR_ASSIGNMENT: {
 170                 struct expression *tmp;
 171
 172                 if (!expr->right)
 173                         break;
 174
 175                 __pass_to_client(expr, RAW_ASSIGNMENT_HOOK);
 176
 177                 /* foo = !bar() */
 178                 if (__handle_condition_assigns(expr))
 179                         break;
 180                 /* foo = (x < 5 ? foo : 5); */
 181                 if (__handle_select_assigns(expr))
 182                         break;
 183                 /* foo = ({frob(); frob(); frob(); 1;}) */
 184                 if (__handle_expr_statement_assigns(expr))
 185                         break;
 186
 187                 __split_expr(expr->right);
 188                 __pass_to_client(expr, ASSIGNMENT_HOOK);
 189                 tmp = strip_expr(expr->right);
 190                 if (tmp->type == EXPR_CALL)
 191                         __pass_to_client(expr, CALL_ASSIGNMENT_HOOK);
 192                 if (get_macro_name(tmp->pos) &&
 193                     get_macro_name(expr->pos) != get_macro_name(tmp->pos))
 194                         __pass_to_client(expr, MACRO_ASSIGNMENT_HOOK);
 195                 __split_expr(expr->left);
 196                 break;
 197         }
 198         case EXPR_DEREF:
 199                 __pass_to_client(expr, DEREF_HOOK);
 200                 __split_expr(expr->deref);
 201                 break;
 202         case EXPR_SLICE:
 203                 __split_expr(expr->base);
 204                 break;
 205         case EXPR_CAST:
 206         case EXPR_FORCE_CAST:
 207                 __pass_to_client(expr, CAST_HOOK);
 208                 __split_expr(expr->cast_expression);
 209                 break;
 210         case EXPR_SIZEOF:
 211                 if (expr->cast_expression)
 212                         __pass_to_client(strip_parens(expr->cast_expression),
 213                                          SIZEOF_HOOK);
 214                 break;
 215         case EXPR_OFFSETOF:
 216         case EXPR_ALIGNOF:
 217                 evaluate_expression(expr);
 218                 break;
 219         case EXPR_CONDITIONAL:
 220         case EXPR_SELECT:
 221                 if (known_condition_true(expr->conditional)) {
 222                         __split_expr(expr->cond_true);
 223                         break;
 224                 }
 225                 if (known_condition_false(expr->conditional)) {
 226                         __split_expr(expr->cond_false);
 227                         break;
 228                 }
 229                 __pass_to_client(expr, SELECT_HOOK);
 230                 __split_whole_condition(expr->conditional);
 231                 __split_expr(expr->cond_true);
 232                 __push_true_states();
 233                 __use_false_states();
 234                 __split_expr(expr->cond_false);
 235                 __merge_true_states();
 236                 break;
 237         case EXPR_CALL:
 238                 if (sym_name_is("__builtin_constant_p", expr->fn))
 239                         break;
 240                 split_expr_list(expr->args);
 241                 __split_expr(expr->fn);
 242                 if (is_inline_func(expr->fn))
 243                         add_inline_function(expr->fn->symbol);
 244                 if (inlinable(expr->fn))
 245                         __inline_call = 1;
 246                 __pass_to_client(expr, FUNCTION_CALL_HOOK);
 247                 __inline_call = 0;
 248                 if (inlinable(expr->fn)) {
 249                         parse_inline(expr);
 250                 }
 251                 __pass_to_client(expr, CALL_HOOK_AFTER_INLINE);
 252                 if (is_noreturn_func(expr->fn))
 253                         nullify_path();
 254                 break;
 255         case EXPR_INITIALIZER:
 256                 split_expr_list(expr->expr_list);
 257                 break;
 258         case EXPR_IDENTIFIER:
 259                 __split_expr(expr->ident_expression);
 260                 break;
 261         case EXPR_INDEX:
 262                 __split_expr(expr->idx_expression);
 263                 break;
 264         case EXPR_POS:
 265                 __split_expr(expr->init_expr);
 266                 break;
 267         case EXPR_SYMBOL:
 268                 __pass_to_client(expr, SYM_HOOK);
 269                 break;
 270         case EXPR_STRING:
 271                 __pass_to_client(expr, STRING_HOOK);
 272                 break;
 273         default:
 274                 break;
 275         };
 276         pop_expression(&big_expression_stack);
 277 }
 278
 279 static int is_forever_loop(struct statement *stmt)
 280 {
 281         struct expression *expr;
 282
 283         expr = strip_expr(stmt->iterator_pre_condition);
 284         if (!expr)
 285                 expr = stmt->iterator_post_condition;
 286         if (!expr) {
 287                 /* this is a for(;;) loop... */
 288                 return 1;
 289         }
 290
 291         if (expr->type == EXPR_VALUE && expr->value == 1)
 292                 return 1;
 293
 294         return 0;
 295 }
 296
 297 static int loop_num;
 298 static char *get_loop_name(int num)
 299 {
 300         char buf[256];
 301
 302         snprintf(buf, 255, "-loop%d", num);
 303         buf[255] = '\0';
 304         return alloc_sname(buf);
 305 }
 306
 307 /*
 308  * Pre Loops are while and for loops.
 309  */
 310 static void handle_pre_loop(struct statement *stmt)
 311 {
 312         int once_through; /* we go through the loop at least once */
 313         struct sm_state *extra_sm = NULL;
 314         int unchanged = 0;
 315         char *loop_name;
 316         struct state_list *slist = NULL;
 317         struct sm_state *sm = NULL;
 318
 319         loop_name = get_loop_name(loop_num);
 320         loop_num++;
 321
 322         __split_stmt(stmt->iterator_pre_statement);
 323
 324         once_through = implied_condition_true(stmt->iterator_pre_condition);
 325
 326         loop_count++;
 327         __push_continues();
 328         __push_breaks();
 329
 330         __merge_gotos(loop_name);
 331
 332         extra_sm = __extra_handle_canonical_loops(stmt, &slist);
 333         __in_pre_condition++;
 334         __pass_to_client(stmt, PRELOOP_HOOK);
 335         __split_whole_condition(stmt->iterator_pre_condition);
 336         __in_pre_condition--;
 337         FOR_EACH_PTR(slist, sm) {
 338                 set_state(sm->owner, sm->name, sm->sym, sm->state);
 339         } END_FOR_EACH_PTR(sm);
 340         free_slist(&slist);
 341         if (extra_sm)
 342                 extra_sm = get_sm_state(extra_sm->owner, extra_sm->name, extra_sm->sym);
 343
 344         if (option_assume_loops)
 345                 once_through = 1;
 346
 347         __split_stmt(stmt->iterator_statement);
 348         __warn_on_silly_pre_loops();
 349         if (is_forever_loop(stmt)) {
 350                 struct state_list *slist;
 351
 352                 __save_gotos(loop_name);
 353
 354                 __push_fake_cur_slist();
 355                 __split_stmt(stmt->iterator_post_statement);
 356                 slist = __pop_fake_cur_slist();
 357
 358                 __discard_continues();
 359                 __discard_false_states();
 360                 __use_breaks();
 361
 362                 if (!__path_is_null())
 363                         __merge_slist_into_cur(slist);
 364                 free_slist(&slist);
 365         } else {
 366                 __merge_continues();
 367                 unchanged = __iterator_unchanged(extra_sm);
 368                 __split_stmt(stmt->iterator_post_statement);
 369                 __save_gotos(loop_name);
 370                 __split_whole_condition(stmt->iterator_pre_condition);
 371                 nullify_path();
 372                 __merge_false_states();
 373                 if (once_through)
 374                         __discard_false_states();
 375                 else
 376                         __merge_false_states();
 377
 378                 if (extra_sm && unchanged)
 379                         __extra_pre_loop_hook_after(extra_sm,
 380                                                 stmt->iterator_post_statement,
 381                                                 stmt->iterator_pre_condition);
 382                 __merge_breaks();
 383         }
 384         loop_count--;
 385 }
 386
 387 /*
 388  * Post loops are do {} while();
 389  */
 390 static void handle_post_loop(struct statement *stmt)
 391 {
 392         char *loop_name;
 393
 394         loop_name = get_loop_name(loop_num);
 395         loop_num++;
 396         loop_count++;
 397
 398         __push_continues();
 399         __push_breaks();
 400         __merge_gotos(loop_name);
 401         __split_stmt(stmt->iterator_statement);
 402         __merge_continues();
 403         if (!is_zero(stmt->iterator_post_condition))
 404                 __save_gotos(loop_name);
 405
 406         if (is_forever_loop(stmt)) {
 407                 __use_breaks();
 408         } else {
 409                 __split_whole_condition(stmt->iterator_post_condition);
 410                 __use_false_states();
 411                 __merge_breaks();
 412         }
 413         loop_count--;
 414 }
 415
 416 static int empty_statement(struct statement *stmt)
 417 {
 418         if (!stmt)
 419                 return 0;
 420         if (stmt->type == STMT_EXPRESSION && !stmt->expression)
 421                 return 1;
 422         return 0;
 423 }
 424
 425 static int last_stmt_on_same_line()
 426 {
 427         struct statement *stmt;
 428         int i = 0;
 429
 430         FOR_EACH_PTR_REVERSE(big_statement_stack, stmt) {
 431                 if (!i++)
 432                         continue;
 433                 if  (stmt->pos.line == get_lineno())
 434                         return 1;
 435                 return 0;
 436         } END_FOR_EACH_PTR_REVERSE(stmt);
 437         return 0;
 438 }
 439
 440 static struct statement *last_stmt;
 441 static int is_last_stmt(struct statement *stmt)
 442 {
 443         if (stmt == last_stmt)
 444                 return 1;
 445         return 0;
 446 }
 447
 448 static void print_unreached_initializers(struct symbol_list *sym_list)
 449 {
 450         struct symbol *sym;
 451
 452         FOR_EACH_PTR(sym_list, sym) {
 453                 if (sym->initializer)
 454                         sm_msg("info: '%s' is not actually initialized (unreached code).",
 455                                 (sym->ident ? sym->ident->name : "this variable"));
 456         } END_FOR_EACH_PTR(sym);
 457 }
 458
 459 static void print_unreached(struct statement *stmt)
 460 {
 461         static int print = 1;
 462
 463         if (!__path_is_null()) {
 464                 print = 1;
 465                 return;
 466         }
 467         if (!print)
 468                 return;
 469
 470         switch (stmt->type) {
 471         case STMT_COMPOUND: /* after a switch before a case stmt */
 472         case STMT_RANGE:
 473         case STMT_CASE:
 474         case STMT_LABEL:
 475                 return;
 476         case STMT_DECLARATION: /* switch (x) { int a; case foo: ... */
 477                 print_unreached_initializers(stmt->declaration);
 478                 return;
 479         case STMT_RETURN: /* gcc complains if you don't have a return statement */
 480                 if (is_last_stmt(stmt))
 481                         return;
 482                 break;
 483         case STMT_GOTO:
 484                 if (!option_spammy)
 485                         return;
 486                 break;
 487         default:
 488                 break;
 489         }
 490         if (!option_spammy && empty_statement(stmt))
 491                 return;
 492         sm_msg("info: ignoring unreachable code.");
 493         print = 0;
 494 }
 495
 496 static void split_asm_constraints(struct expression_list *expr_list)
 497 {
 498         struct expression *expr;
 499         int state = 0;
 500
 501         FOR_EACH_PTR(expr_list, expr) {
 502                 switch (state) {
 503                 case 0: /* identifier */
 504                 case 1: /* constraint */
 505                         state++;
 506                         continue;
 507                 case 2: /* expression */
 508                         state = 0;
 509                         __split_expr(expr);
 510                         continue;
 511                 }
 512         } END_FOR_EACH_PTR(expr);
 513 }
 514
 515 static int is_case_val(struct statement *stmt, sval_t sval)
 516 {
 517         sval_t case_sval;
 518
 519         if (stmt->type != STMT_CASE)
 520                 return 0;
 521         if (!stmt->case_expression) {
 522                 __set_default();
 523                 return 1;
 524         }
 525         if (!get_value(stmt->case_expression, &case_sval))
 526                 return 0;
 527         if (case_sval.value == sval.value)
 528                 return 1;
 529         return 0;
 530 }
 531
 532 static void split_known_switch(struct statement *stmt, sval_t sval)
 533 {
 534         struct statement *tmp;
 535
 536         __split_expr(stmt->switch_expression);
 537
 538         push_expression(&switch_expr_stack, stmt->switch_expression);
 539         __save_switch_states(top_expression(switch_expr_stack));
 540         nullify_path();
 541         __push_default();
 542         __push_breaks();
 543
 544         stmt = stmt->switch_statement;
 545
 546         if (!last_stmt)
 547                 last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 548
 549         __push_scope_hooks();
 550         FOR_EACH_PTR(stmt->stmts, tmp) {
 551                 __smatch_lineno = tmp->pos.line;
 552                 if (is_case_val(tmp, sval)) {
 553                         __merge_switches(top_expression(switch_expr_stack),
 554                                          stmt->case_expression);
 555                         __pass_case_to_client(top_expression(switch_expr_stack),
 556                                               stmt->case_expression);
 557                 }
 558                 if (__path_is_null())
 559                         continue;
 560                 __split_stmt(tmp);
 561                 if (__path_is_null()) {
 562                         __set_default();
 563                         goto out;
 564                 }
 565         } END_FOR_EACH_PTR(tmp);
 566 out:
 567         __call_scope_hooks();
 568         if (!__pop_default())
 569                 __merge_switches(top_expression(switch_expr_stack),
 570                                  NULL);
 571         __discard_switches();
 572         __merge_breaks();
 573         pop_expression(&switch_expr_stack);
 574 }
 575
 576 void __split_stmt(struct statement *stmt)
 577 {
 578         sval_t sval;
 579
 580         if (!stmt)
 581                 return;
 582
 583         if (out_of_memory() || __bail_on_rest_of_function) {
 584                 static char *printed = NULL;
 585
 586                 if (printed != cur_func)
 587                         sm_msg("Function too hairy.  Giving up.");
 588                 final_pass = 0;  /* turn off sm_msg() from here */
 589                 printed = cur_func;
 590                 return;
 591         }
 592
 593         add_ptr_list(&big_statement_stack, stmt);
 594         free_expression_stack(&big_expression_stack);
 595         set_position(stmt->pos);
 596         print_unreached(stmt);
 597         __pass_to_client(stmt, STMT_HOOK);
 598
 599         switch (stmt->type) {
 600         case STMT_DECLARATION:
 601                 split_declaration(stmt->declaration);
 602                 return;
 603         case STMT_RETURN:
 604                 __split_expr(stmt->ret_value);
 605                 __pass_to_client(stmt->ret_value, RETURN_HOOK);
 606                 nullify_path();
 607                 return;
 608         case STMT_EXPRESSION:
 609                 __split_expr(stmt->expression);
 610                 return;
 611         case STMT_COMPOUND: {
 612                 struct statement *tmp;
 613
 614                 if (!last_stmt)
 615                         last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 616                 __push_scope_hooks();
 617                 FOR_EACH_PTR(stmt->stmts, tmp) {
 618                         __split_stmt(tmp);
 619                 } END_FOR_EACH_PTR(tmp);
 620                 __call_scope_hooks();
 621                 return;
 622         }
 623         case STMT_IF:
 624                 if (known_condition_true(stmt->if_conditional)) {
 625                         __split_stmt(stmt->if_true);
 626                         return;
 627                 }
 628                 if (known_condition_false(stmt->if_conditional)) {
 629                         __split_stmt(stmt->if_false);
 630                         return;
 631                 }
 632                 if (option_known_conditions &&
 633                     implied_condition_true(stmt->if_conditional)) {
 634                         sm_info("this condition is true.");
 635                         __split_stmt(stmt->if_true);
 636                         return;
 637                 }
 638                 if (option_known_conditions &&
 639                     implied_condition_false(stmt->if_conditional)) {
 640                         sm_info("this condition is false.");
 641                         __split_stmt(stmt->if_false);
 642                         return;
 643                 }
 644                 __split_whole_condition(stmt->if_conditional);
 645                 __split_stmt(stmt->if_true);
 646                 if (empty_statement(stmt->if_true) &&
 647                         last_stmt_on_same_line() &&
 648                         !get_macro_name(stmt->if_true->pos))
 649                         sm_msg("warn: if();");
 650                 __push_true_states();
 651                 __use_false_states();
 652                 __split_stmt(stmt->if_false);
 653                 __merge_true_states();
 654                 return;
 655         case STMT_ITERATOR:
 656                 if (stmt->iterator_pre_condition)
 657                         handle_pre_loop(stmt);
 658                 else if (stmt->iterator_post_condition)
 659                         handle_post_loop(stmt);
 660                 else {
 661                         // these are for(;;) type loops.
 662                         handle_pre_loop(stmt);
 663                 }
 664                 return;
 665         case STMT_SWITCH:
 666                 if (get_value(stmt->switch_expression, &sval)) {
 667                         split_known_switch(stmt, sval);
 668                         return;
 669                 }
 670                 __split_expr(stmt->switch_expression);
 671                 push_expression(&switch_expr_stack, stmt->switch_expression);
 672                 __save_switch_states(top_expression(switch_expr_stack));
 673                 nullify_path();
 674                 __push_default();
 675                 __push_breaks();
 676                 __split_stmt(stmt->switch_statement);
 677                 if (!__pop_default())
 678                         __merge_switches(top_expression(switch_expr_stack),
 679                                       NULL);
 680                 __discard_switches();
 681                 __merge_breaks();
 682                 pop_expression(&switch_expr_stack);
 683                 return;
 684         case STMT_CASE:
 685                 __merge_switches(top_expression(switch_expr_stack),
 686                                       stmt->case_expression);
 687                 __pass_case_to_client(top_expression(switch_expr_stack),
 688                                       stmt->case_expression);
 689                 if (!stmt->case_expression)
 690                         __set_default();
 691                 __split_expr(stmt->case_expression);
 692                 __split_expr(stmt->case_to);
 693                 __split_stmt(stmt->case_statement);
 694                 return;
 695         case STMT_LABEL:
 696                 if (stmt->label_identifier &&
 697                     stmt->label_identifier->type == SYM_LABEL &&
 698                     stmt->label_identifier->ident) {
 699                         loop_count = 1000000;
 700                         __merge_gotos(stmt->label_identifier->ident->name);
 701                 }
 702                 __split_stmt(stmt->label_statement);
 703                 return;
 704         case STMT_GOTO:
 705                 __split_expr(stmt->goto_expression);
 706                 if (stmt->goto_label && stmt->goto_label->type == SYM_NODE) {
 707                         if (!strcmp(stmt->goto_label->ident->name, "break")) {
 708                                 __process_breaks();
 709                         } else if (!strcmp(stmt->goto_label->ident->name,
 710                                            "continue")) {
 711                                 __process_continues();
 712                         }
 713                 } else if (stmt->goto_label &&
 714                            stmt->goto_label->type == SYM_LABEL &&
 715                            stmt->goto_label->ident) {
 716                         __save_gotos(stmt->goto_label->ident->name);
 717                 }
 718                 nullify_path();
 719                 return;
 720         case STMT_NONE:
 721                 return;
 722         case STMT_ASM:
 723                 __pass_to_client(stmt, ASM_HOOK);
 724                 __split_expr(stmt->asm_string);
 725                 split_asm_constraints(stmt->asm_outputs);
 726                 split_asm_constraints(stmt->asm_inputs);
 727                 split_asm_constraints(stmt->asm_clobbers);
 728                 return;
 729         case STMT_CONTEXT:
 730                 return;
 731         case STMT_RANGE:
 732                 __split_expr(stmt->range_expression);
 733                 __split_expr(stmt->range_low);
 734                 __split_expr(stmt->range_high);
 735                 return;
 736         }
 737 }
 738
 739 static void split_expr_list(struct expression_list *expr_list)
 740 {
 741         struct expression *expr;
 742
 743         FOR_EACH_PTR(expr_list, expr) {
 744                 __split_expr(expr);
 745         } END_FOR_EACH_PTR(expr);
 746 }
 747
 748 static void split_sym(struct symbol *sym)
 749 {
 750         if (!sym)
 751                 return;
 752         if (!(sym->namespace & NS_SYMBOL))
 753                 return;
 754
 755         __split_stmt(sym->stmt);
 756         __split_expr(sym->array_size);
 757         split_symlist(sym->arguments);
 758         split_symlist(sym->symbol_list);
 759         __split_stmt(sym->inline_stmt);
 760         split_symlist(sym->inline_symbol_list);
 761 }
 762
 763 static void split_symlist(struct symbol_list *sym_list)
 764 {
 765         struct symbol *sym;
 766
 767         FOR_EACH_PTR(sym_list, sym) {
 768                 split_sym(sym);
 769         } END_FOR_EACH_PTR(sym);
 770 }
 771
 772 static void fake_member_assigns(struct symbol *sym)
 773 {
 774         struct expression *symbol, *deref, *assign, *tmp;
 775
 776         symbol = symbol_expression(sym);
 777         FOR_EACH_PTR(sym->initializer->expr_list, tmp) {
 778                 if (tmp->type != EXPR_IDENTIFIER) /* how to handle arrays?? */
 779                         continue;
 780                 deref = member_expression(symbol, '.', tmp->expr_ident);
 781                 assign = assign_expression(deref, tmp->ident_expression);
 782                 __split_expr(assign);
 783         } END_FOR_EACH_PTR(tmp);
 784 }
 785
 786 static void fake_assign_expr(struct symbol *sym)
 787 {
 788         struct expression *assign, *symbol;
 789
 790         symbol = symbol_expression(sym);
 791         assign = assign_expression(symbol, sym->initializer);
 792         __split_expr(assign);
 793 }
 794
 795 static void do_initializer_stuff(struct symbol *sym)
 796 {
 797         if (!sym->initializer)
 798                 return;
 799         if (sym->initializer->type == EXPR_INITIALIZER)
 800                 fake_member_assigns(sym);
 801         else
 802                 fake_assign_expr(sym);
 803 }
 804
 805 static void split_declaration(struct symbol_list *sym_list)
 806 {
 807         struct symbol *sym;
 808
 809         FOR_EACH_PTR(sym_list, sym) {
 810                 __pass_to_client(sym, DECLARATION_HOOK);
 811                 do_initializer_stuff(sym);
 812                 split_sym(sym);
 813         } END_FOR_EACH_PTR(sym);
 814 }
 815
 816 static void fake_global_assign(struct symbol *sym)
 817 {
 818         struct expression *assign, *symbol;
 819
 820         if (!sym->initializer)
 821                 return;
 822         if (sym->initializer->type == EXPR_INITIALIZER) {
 823                 struct expression *deref, *tmp;
 824
 825                 symbol = symbol_expression(sym);
 826                 FOR_EACH_PTR(sym->initializer->expr_list, tmp) {
 827                         if (tmp->type != EXPR_IDENTIFIER) /* how to handle arrays?? */
 828                                 continue;
 829                         deref = member_expression(symbol, '.', tmp->expr_ident);
 830                         assign = assign_expression(deref, tmp->ident_expression);
 831                         __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
 832                 } END_FOR_EACH_PTR(tmp);
 833         } else {
 834                 symbol = symbol_expression(sym);
 835                 assign = assign_expression(symbol, sym->initializer);
 836                 __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
 837         }
 838 }
 839
 840 static void split_function(struct symbol *sym)
 841 {
 842         struct symbol *base_type = get_base_type(sym);
 843
 844         cur_func_sym = sym;
 845         if (sym->ident)
 846                 cur_func = sym->ident->name;
 847         __smatch_lineno = sym->pos.line;
 848         last_stmt = NULL;
 849         loop_count = 0;
 850         sm_debug("new function:  %s\n", cur_func);
 851         __slist_id = 0;
 852         if (option_two_passes) {
 853                 __unnullify_path();
 854                 loop_num = 0;
 855                 final_pass = 0;
 856                 __pass_to_client(sym, FUNC_DEF_HOOK);
 857                 __pass_to_client(sym, AFTER_DEF_HOOK);
 858                 __split_stmt(base_type->stmt);
 859                 __split_stmt(base_type->inline_stmt);
 860                 nullify_path();
 861         }
 862         __unnullify_path();
 863         loop_num = 0;
 864         final_pass = 1;
 865         __pass_to_client(sym, FUNC_DEF_HOOK);
 866         __pass_to_client(sym, AFTER_DEF_HOOK);
 867         __split_stmt(base_type->stmt);
 868         __split_stmt(base_type->inline_stmt);
 869         __pass_to_client(sym, END_FUNC_HOOK);
 870         cur_func = NULL;
 871         clear_all_states();
 872         free_data_info_allocs();
 873         free_expression_stack(&switch_expr_stack);
 874         __free_ptr_list((struct ptr_list **)&big_statement_stack);
 875         __bail_on_rest_of_function = 0;
 876 }
 877
 878 static void parse_inline(struct expression *call)
 879 {
 880         struct symbol *base_type;
 881         int loop_num_bak = loop_num;
 882         int final_pass_bak = final_pass;
 883         char *cur_func_bak = cur_func;
 884         struct statement_list *big_statement_stack_bak = big_statement_stack;
 885         struct expression_list *big_expression_stack_bak = big_expression_stack;
 886         struct expression_list *switch_expr_stack_bak = switch_expr_stack;
 887         struct symbol *cur_func_sym_bak = cur_func_sym;
 888
 889         __pass_to_client(call, INLINE_FN_START);
 890         final_pass = 0;  /* don't print anything */
 891         __inline_fn = call;
 892
 893         base_type = get_base_type(call->fn->symbol);
 894         cur_func_sym = call->fn->symbol;
 895         if (call->fn->symbol->ident)
 896                 cur_func = call->fn->symbol->ident->name;
 897         else
 898                 cur_func = NULL;
 899         set_position(call->fn->symbol->pos);
 900
 901         save_all_states();
 902         nullify_all_states();
 903         big_statement_stack = NULL;
 904         big_expression_stack = NULL;
 905         switch_expr_stack = NULL;
 906
 907         sm_debug("inline function:  %s\n", cur_func);
 908         __unnullify_path();
 909         loop_num = 0;
 910         __pass_to_client(call->fn->symbol, FUNC_DEF_HOOK);
 911         __pass_to_client(call->fn->symbol, AFTER_DEF_HOOK);
 912         __split_stmt(base_type->stmt);
 913         __split_stmt(base_type->inline_stmt);
 914         __pass_to_client(call->fn->symbol, END_FUNC_HOOK);
 915
 916         free_expression_stack(&switch_expr_stack);
 917         __free_ptr_list((struct ptr_list **)&big_statement_stack);
 918         nullify_path();
 919
 920         loop_num = loop_num_bak;
 921         final_pass = final_pass_bak;
 922         cur_func_sym = cur_func_sym_bak;
 923         cur_func = cur_func_bak;
 924         big_statement_stack = big_statement_stack_bak;
 925         big_expression_stack = big_expression_stack_bak;
 926         switch_expr_stack = switch_expr_stack_bak;
 927
 928         restore_all_states();
 929         set_position(call->pos);
 930         __inline_fn = NULL;
 931         __pass_to_client(call, INLINE_FN_END);
 932 }
 933
 934 static struct symbol_list *inlines_called;
 935 static void add_inline_function(struct symbol *sym)
 936 {
 937         static struct symbol_list *already_added;
 938         struct symbol *tmp;
 939
 940         FOR_EACH_PTR(already_added, tmp) {
 941                 if (tmp == sym)
 942                         return;
 943         } END_FOR_EACH_PTR(tmp);
 944
 945         add_ptr_list(&already_added, sym);
 946         add_ptr_list(&inlines_called, sym);
 947 }
 948
 949 static void process_inlines()
 950 {
 951         struct symbol *tmp;
 952
 953         FOR_EACH_PTR(inlines_called, tmp) {
 954                 split_function(tmp);
 955         } END_FOR_EACH_PTR(tmp);
 956         free_ptr_list(&inlines_called);
 957 }
 958
 959 static void split_functions(struct symbol_list *sym_list)
 960 {
 961         struct symbol *sym;
 962
 963         FOR_EACH_PTR(sym_list, sym) {
 964                 set_position(sym->pos);
 965                 if (sym->type == SYM_NODE && get_base_type(sym)->type == SYM_FN) {
 966                         split_function(sym);
 967                         process_inlines();
 968                 } else {
 969                         __pass_to_client(sym, BASE_HOOK);
 970                         fake_global_assign(sym);
 971                 }
 972         } END_FOR_EACH_PTR(sym);
 973         __pass_to_client_no_data(END_FILE_HOOK);
 974 }
 975
 976 void smatch(int argc, char **argv)
 977 {
 978
 979         struct string_list *filelist = NULL;
 980         struct symbol_list *sym_list;
 981
 982         if (argc < 2) {
 983                 printf("Usage:  smatch [--debug] <filename.c>\n");
 984                 exit(1);
 985         }
 986         sparse_initialize(argc, argv, &filelist);
 987         FOR_EACH_PTR_NOTAG(filelist, base_file) {
 988                 if (option_file_output) {
 989                         char buf[256];
 990
 991                         snprintf(buf, sizeof(buf), "%s.smatch", base_file);
 992                         sm_outfd = fopen(buf, "w");
 993                         if (!sm_outfd) {
 994                                 printf("Error:  Cannot open %s\n", base_file);
 995                                 exit(1);
 996                         }
 997                 }
 998                 sym_list = sparse_keep_tokens(base_file);
 999                 split_functions(sym_list);
1000         } END_FOR_EACH_PTR_NOTAG(base_file);
1001 }