2 * Copyright (C) 2008 Dan Carpenter.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
19 * smatch_extra.c is supposed to track the value of every variable.
31 #include "smatch_slist.h"
32 #include "smatch_extra.h"
37 static void match_link_modify(struct sm_state
*sm
, struct expression
*mod_expr
);
39 struct string_list
*__ignored_macros
= NULL
;
40 static int in_warn_on_macro(void)
42 struct statement
*stmt
;
46 stmt
= get_current_statement();
49 macro
= get_macro_name(stmt
->pos
);
53 FOR_EACH_PTR(__ignored_macros
, tmp
) {
54 if (!strcmp(tmp
, macro
))
56 } END_FOR_EACH_PTR(tmp
);
60 typedef void (mod_hook
)(const char *name
, struct symbol
*sym
, struct smatch_state
*state
);
61 DECLARE_PTR_LIST(void_fn_list
, mod_hook
*);
62 static struct void_fn_list
*extra_mod_hooks
;
63 void add_extra_mod_hook(mod_hook
*fn
)
65 mod_hook
**p
= malloc(sizeof(mod_hook
*));
67 add_ptr_list(&extra_mod_hooks
, p
);
70 void call_extra_mod_hooks(const char *name
, struct symbol
*sym
, struct smatch_state
*state
)
74 FOR_EACH_PTR(extra_mod_hooks
, fn
) {
75 (*fn
)(name
, sym
, state
);
76 } END_FOR_EACH_PTR(fn
);
79 struct sm_state
*set_extra_mod_helper(const char *name
, struct symbol
*sym
, struct smatch_state
*state
)
81 remove_from_equiv(name
, sym
);
82 call_extra_mod_hooks(name
, sym
, state
);
83 if (__in_fake_assign
&& estate_is_unknown(state
) && !get_state(SMATCH_EXTRA
, name
, sym
))
85 return set_state(SMATCH_EXTRA
, name
, sym
, state
);
88 static char *get_other_name_sym(const char *name
, struct symbol
*sym
, struct symbol
**new_sym
)
90 struct expression
*assigned
;
91 char *orig_name
= NULL
;
101 skip
= strlen(sym
->ident
->name
);
102 if (name
[skip
] != '-' || name
[skip
+ 1] != '>')
106 assigned
= get_assigned_expr_name_sym(sym
->ident
->name
, sym
);
109 if (assigned
->type
== EXPR_PREOP
|| assigned
->op
== '&') {
111 orig_name
= expr_to_var_sym(assigned
, new_sym
);
112 if (!orig_name
|| !*new_sym
)
115 snprintf(buf
, sizeof(buf
), "%s.%s", orig_name
+ 1, name
+ skip
);
116 ret
= alloc_string(buf
);
117 free_string(orig_name
);
121 if (assigned
->type
!= EXPR_DEREF
)
124 orig_name
= expr_to_var_sym(assigned
, new_sym
);
125 if (!orig_name
|| !*new_sym
)
128 snprintf(buf
, sizeof(buf
), "%s->%s", orig_name
, name
+ skip
);
129 ret
= alloc_string(buf
);
130 free_string(orig_name
);
134 free_string(orig_name
);
138 struct sm_state
*set_extra_mod(const char *name
, struct symbol
*sym
, struct smatch_state
*state
)
141 struct symbol
*new_sym
;
144 sm
= set_extra_mod_helper(name
, sym
, state
);
145 new_name
= get_other_name_sym(name
, sym
, &new_sym
);
146 if (new_name
&& new_sym
)
147 set_extra_mod_helper(new_name
, new_sym
, state
);
148 free_string(new_name
);
152 static void clear_array_states(struct expression
*array
)
156 sm
= get_sm_state_expr(link_id
, array
);
158 match_link_modify(sm
, NULL
);
161 static struct sm_state
*set_extra_array_mod(struct expression
*expr
, struct smatch_state
*state
)
163 struct expression
*array
;
164 struct var_sym_list
*vsl
;
168 struct sm_state
*ret
= NULL
;
170 array
= get_array_base(expr
);
172 name
= expr_to_chunk_sym_vsl(expr
, &sym
, &vsl
);
174 clear_array_states(array
);
178 FOR_EACH_PTR(vsl
, vs
) {
179 store_link(link_id
, vs
->var
, vs
->sym
, name
, sym
);
180 } END_FOR_EACH_PTR(vs
);
182 call_extra_mod_hooks(name
, sym
, state
);
183 ret
= set_state(SMATCH_EXTRA
, name
, sym
, state
);
189 struct sm_state
*set_extra_expr_mod(struct expression
*expr
, struct smatch_state
*state
)
193 struct sm_state
*ret
= NULL
;
196 return set_extra_array_mod(expr
, state
);
198 expr
= strip_expr(expr
);
199 name
= expr_to_var_sym(expr
, &sym
);
202 ret
= set_extra_mod(name
, sym
, state
);
208 void set_extra_nomod(const char *name
, struct symbol
*sym
, struct smatch_state
*state
)
211 struct symbol
*new_sym
;
212 struct relation
*rel
;
213 struct smatch_state
*orig_state
;
215 orig_state
= get_state(SMATCH_EXTRA
, name
, sym
);
217 new_name
= get_other_name_sym(name
, sym
, &new_sym
);
218 if (new_name
&& new_sym
)
219 set_state(SMATCH_EXTRA
, new_name
, new_sym
, state
);
220 free_string(new_name
);
222 if (!estate_related(orig_state
)) {
223 set_state(SMATCH_EXTRA
, name
, sym
, state
);
227 set_related(state
, estate_related(orig_state
));
228 FOR_EACH_PTR(estate_related(orig_state
), rel
) {
229 struct smatch_state
*estate
;
231 if (option_debug_related
)
232 sm_msg("%s updating related %s to %s", name
, rel
->name
, state
->name
);
233 estate
= get_state(SMATCH_EXTRA
, rel
->name
, rel
->sym
);
236 set_state(SMATCH_EXTRA
, rel
->name
, rel
->sym
, clone_estate_cast(estate_type(estate
), state
));
237 } END_FOR_EACH_PTR(rel
);
241 * This is for return_implies_state() hooks which modify a SMATCH_EXTRA state
243 void set_extra_expr_nomod(struct expression
*expr
, struct smatch_state
*state
)
248 name
= expr_to_var_sym(expr
, &sym
);
251 set_extra_nomod(name
, sym
, state
);
257 static void set_extra_true_false(const char *name
, struct symbol
*sym
,
258 struct smatch_state
*true_state
,
259 struct smatch_state
*false_state
)
262 struct symbol
*new_sym
;
263 struct relation
*rel
;
264 struct smatch_state
*orig_state
;
266 if (!true_state
&& !false_state
)
269 if (in_warn_on_macro())
272 new_name
= get_other_name_sym(name
, sym
, &new_sym
);
273 if (new_name
&& new_sym
)
274 set_true_false_states(SMATCH_EXTRA
, new_name
, new_sym
, true_state
, false_state
);
275 free_string(new_name
);
277 orig_state
= get_state(SMATCH_EXTRA
, name
, sym
);
279 if (!estate_related(orig_state
)) {
280 set_true_false_states(SMATCH_EXTRA
, name
, sym
, true_state
, false_state
);
285 set_related(true_state
, estate_related(orig_state
));
287 set_related(false_state
, estate_related(orig_state
));
289 FOR_EACH_PTR(estate_related(orig_state
), rel
) {
290 set_true_false_states(SMATCH_EXTRA
, rel
->name
, rel
->sym
,
291 true_state
, false_state
);
292 } END_FOR_EACH_PTR(rel
);
295 static void set_extra_chunk_true_false(struct expression
*expr
,
296 struct smatch_state
*true_state
,
297 struct smatch_state
*false_state
)
299 struct var_sym_list
*vsl
;
305 if (in_warn_on_macro())
308 type
= get_type(expr
);
312 name
= expr_to_chunk_sym_vsl(expr
, &sym
, &vsl
);
315 FOR_EACH_PTR(vsl
, vs
) {
316 store_link(link_id
, vs
->var
, vs
->sym
, name
, sym
);
317 } END_FOR_EACH_PTR(vs
);
319 set_true_false_states(SMATCH_EXTRA
, name
, sym
,
320 clone_estate(true_state
),
321 clone_estate(false_state
));
326 static void set_extra_expr_true_false(struct expression
*expr
,
327 struct smatch_state
*true_state
,
328 struct smatch_state
*false_state
)
334 if (!true_state
&& !false_state
)
337 if (get_value(expr
, &sval
))
340 expr
= strip_expr(expr
);
341 name
= expr_to_var_sym(expr
, &sym
);
344 set_extra_chunk_true_false(expr
, true_state
, false_state
);
347 set_extra_true_false(name
, sym
, true_state
, false_state
);
351 static struct sm_state
*handle_canonical_while_count_down(struct statement
*loop
)
353 struct expression
*iter_var
;
354 struct expression
*condition
;
356 struct smatch_state
*estate
;
359 condition
= strip_expr(loop
->iterator_pre_condition
);
362 if (condition
->type
!= EXPR_PREOP
&& condition
->type
!= EXPR_POSTOP
)
364 if (condition
->op
!= SPECIAL_DECREMENT
)
367 iter_var
= condition
->unop
;
368 sm
= get_sm_state_expr(SMATCH_EXTRA
, iter_var
);
371 if (sval_cmp_val(estate_min(sm
->state
), 0) < 0)
373 start
= estate_max(sm
->state
);
374 if (sval_cmp_val(start
, 0) <= 0)
376 if (!sval_is_max(start
))
379 if (condition
->type
== EXPR_PREOP
) {
380 estate
= alloc_estate_range(sval_type_val(start
.type
, 1), start
);
381 if (estate_has_hard_max(sm
->state
))
382 estate_set_hard_max(estate
);
383 estate_copy_fuzzy_max(estate
, sm
->state
);
384 set_extra_expr_mod(iter_var
, estate
);
386 if (condition
->type
== EXPR_POSTOP
) {
387 estate
= alloc_estate_range(sval_type_val(start
.type
, 0), start
);
388 if (estate_has_hard_max(sm
->state
))
389 estate_set_hard_max(estate
);
390 estate_copy_fuzzy_max(estate
, sm
->state
);
391 set_extra_expr_mod(iter_var
, estate
);
393 return get_sm_state_expr(SMATCH_EXTRA
, iter_var
);
396 static struct sm_state
*handle_canonical_for_inc(struct expression
*iter_expr
,
397 struct expression
*condition
)
399 struct expression
*iter_var
;
401 struct smatch_state
*estate
;
402 sval_t start
, end
, max
;
404 iter_var
= iter_expr
->unop
;
405 sm
= get_sm_state_expr(SMATCH_EXTRA
, iter_var
);
408 if (!estate_get_single_value(sm
->state
, &start
))
410 if (get_implied_max(condition
->right
, &end
))
411 end
= sval_cast(get_type(iter_var
), end
);
413 end
= sval_type_max(get_type(iter_var
));
415 if (get_sm_state_expr(SMATCH_EXTRA
, condition
->left
) != sm
)
418 switch (condition
->op
) {
419 case SPECIAL_UNSIGNED_LT
:
420 case SPECIAL_NOTEQUAL
:
422 if (!sval_is_min(end
))
425 case SPECIAL_UNSIGNED_LTE
:
431 if (sval_cmp(end
, start
) < 0)
433 estate
= alloc_estate_range(start
, end
);
434 if (get_hard_max(condition
->right
, &max
)) {
435 estate_set_hard_max(estate
);
436 if (condition
->op
== '<' ||
437 condition
->op
== SPECIAL_UNSIGNED_LT
||
438 condition
->op
== SPECIAL_NOTEQUAL
)
440 estate_set_fuzzy_max(estate
, max
);
442 set_extra_expr_mod(iter_var
, estate
);
443 return get_sm_state_expr(SMATCH_EXTRA
, iter_var
);
446 static struct sm_state
*handle_canonical_for_dec(struct expression
*iter_expr
,
447 struct expression
*condition
)
449 struct expression
*iter_var
;
451 struct smatch_state
*estate
;
454 iter_var
= iter_expr
->unop
;
455 sm
= get_sm_state_expr(SMATCH_EXTRA
, iter_var
);
458 if (!estate_get_single_value(sm
->state
, &start
))
460 if (!get_implied_min(condition
->right
, &end
))
461 end
= sval_type_min(get_type(iter_var
));
462 if (get_sm_state_expr(SMATCH_EXTRA
, condition
->left
) != sm
)
465 switch (condition
->op
) {
466 case SPECIAL_NOTEQUAL
:
468 if (!sval_is_min(end
) && !sval_is_max(end
))
476 if (sval_cmp(end
, start
) > 0)
478 estate
= alloc_estate_range(end
, start
);
479 estate_set_hard_max(estate
);
480 estate_set_fuzzy_max(estate
, estate_get_fuzzy_max(estate
));
481 set_extra_expr_mod(iter_var
, estate
);
482 return get_sm_state_expr(SMATCH_EXTRA
, iter_var
);
485 static struct sm_state
*handle_canonical_for_loops(struct statement
*loop
)
487 struct expression
*iter_expr
;
488 struct expression
*condition
;
490 if (!loop
->iterator_post_statement
)
492 if (loop
->iterator_post_statement
->type
!= STMT_EXPRESSION
)
494 iter_expr
= loop
->iterator_post_statement
->expression
;
495 if (!loop
->iterator_pre_condition
)
497 if (loop
->iterator_pre_condition
->type
!= EXPR_COMPARE
)
499 condition
= loop
->iterator_pre_condition
;
501 if (iter_expr
->op
== SPECIAL_INCREMENT
)
502 return handle_canonical_for_inc(iter_expr
, condition
);
503 if (iter_expr
->op
== SPECIAL_DECREMENT
)
504 return handle_canonical_for_dec(iter_expr
, condition
);
508 struct sm_state
*__extra_handle_canonical_loops(struct statement
*loop
, struct stree
**stree
)
510 struct sm_state
*ret
;
512 __push_fake_cur_stree();
513 if (!loop
->iterator_post_statement
)
514 ret
= handle_canonical_while_count_down(loop
);
516 ret
= handle_canonical_for_loops(loop
);
517 *stree
= __pop_fake_cur_stree();
521 int __iterator_unchanged(struct sm_state
*sm
)
525 if (get_sm_state(my_id
, sm
->name
, sm
->sym
) == sm
)
530 static void while_count_down_after(struct sm_state
*sm
, struct expression
*condition
)
534 /* paranoid checking. prolly not needed */
535 condition
= strip_expr(condition
);
538 if (condition
->type
!= EXPR_PREOP
&& condition
->type
!= EXPR_POSTOP
)
540 if (condition
->op
!= SPECIAL_DECREMENT
)
542 after_value
= estate_min(sm
->state
);
544 set_extra_mod(sm
->name
, sm
->sym
, alloc_estate_sval(after_value
));
547 void __extra_pre_loop_hook_after(struct sm_state
*sm
,
548 struct statement
*iterator
,
549 struct expression
*condition
)
551 struct expression
*iter_expr
;
553 struct smatch_state
*state
;
556 while_count_down_after(sm
, condition
);
560 iter_expr
= iterator
->expression
;
562 if (condition
->type
!= EXPR_COMPARE
)
564 if (iter_expr
->op
== SPECIAL_INCREMENT
) {
565 limit
= sval_binop(estate_max(sm
->state
), '+',
566 sval_type_val(estate_type(sm
->state
), 1));
568 limit
= sval_binop(estate_min(sm
->state
), '-',
569 sval_type_val(estate_type(sm
->state
), 1));
571 if (!estate_has_hard_max(sm
->state
) && !__has_breaks()) {
572 if (iter_expr
->op
== SPECIAL_INCREMENT
)
573 state
= alloc_estate_range(estate_min(sm
->state
), limit
);
575 state
= alloc_estate_range(limit
, estate_max(sm
->state
));
577 state
= alloc_estate_sval(limit
);
579 if (!estate_has_hard_max(sm
->state
)) {
580 estate_clear_hard_max(state
);
582 if (estate_has_fuzzy_max(sm
->state
)) {
583 sval_t hmax
= estate_get_fuzzy_max(sm
->state
);
584 sval_t max
= estate_max(sm
->state
);
586 if (sval_cmp(hmax
, max
) != 0)
587 estate_clear_fuzzy_max(state
);
588 } else if (!estate_has_fuzzy_max(sm
->state
)) {
589 estate_clear_fuzzy_max(state
);
592 set_extra_mod(sm
->name
, sm
->sym
, state
);
595 static struct stree
*unmatched_stree
;
596 static struct smatch_state
*unmatched_state(struct sm_state
*sm
)
598 struct smatch_state
*state
;
600 if (unmatched_stree
) {
601 state
= get_state_stree(unmatched_stree
, SMATCH_EXTRA
, sm
->name
, sm
->sym
);
605 if (parent_is_gone_var_sym(sm
->name
, sm
->sym
))
606 return alloc_estate_empty();
607 return alloc_estate_whole(estate_type(sm
->state
));
610 static void clear_the_pointed_at(struct expression
*expr
)
615 struct sm_state
*tmp
;
617 name
= expr_to_var_sym(expr
, &sym
);
621 stree
= __get_cur_stree();
622 FOR_EACH_MY_SM(SMATCH_EXTRA
, stree
, tmp
) {
623 if (tmp
->name
[0] != '*')
627 if (strcmp(tmp
->name
+ 1, name
) != 0)
629 set_extra_mod(tmp
->name
, tmp
->sym
, alloc_estate_whole(estate_type(tmp
->state
)));
630 } END_FOR_EACH_SM(tmp
);
636 static void match_function_call(struct expression
*expr
)
638 struct expression
*arg
;
639 struct expression
*tmp
;
641 /* if we have the db this is handled in smatch_function_hooks.c */
644 if (inlinable(expr
->fn
))
647 FOR_EACH_PTR(expr
->args
, arg
) {
648 tmp
= strip_expr(arg
);
649 if (tmp
->type
== EXPR_PREOP
&& tmp
->op
== '&')
650 set_extra_expr_mod(tmp
->unop
, alloc_estate_whole(get_type(tmp
->unop
)));
652 clear_the_pointed_at(tmp
);
653 } END_FOR_EACH_PTR(arg
);
656 static int values_fit_type(struct expression
*left
, struct expression
*right
)
658 struct range_list
*rl
;
661 type
= get_type(left
);
664 get_absolute_rl(right
, &rl
);
665 if (type_unsigned(type
) && sval_is_negative(rl_min(rl
)))
667 if (sval_cmp(sval_type_min(type
), rl_min(rl
)) > 0)
669 if (sval_cmp(sval_type_max(type
), rl_max(rl
)) < 0)
674 static void save_chunk_info(struct expression
*left
, struct expression
*right
)
676 struct var_sym_list
*vsl
;
678 struct expression
*add_expr
;
684 if (right
->type
!= EXPR_BINOP
|| right
->op
!= '-')
686 if (!get_value(right
->left
, &sval
))
688 if (!expr_to_sym(right
->right
))
691 add_expr
= binop_expression(left
, '+', right
->right
);
692 type
= get_type(add_expr
);
695 name
= expr_to_chunk_sym_vsl(add_expr
, &sym
, &vsl
);
698 FOR_EACH_PTR(vsl
, vs
) {
699 store_link(link_id
, vs
->var
, vs
->sym
, name
, sym
);
700 } END_FOR_EACH_PTR(vs
);
702 set_state(SMATCH_EXTRA
, name
, sym
, alloc_estate_sval(sval_cast(type
, sval
)));
707 static void do_array_assign(struct expression
*left
, int op
, struct expression
*right
)
709 struct range_list
*rl
;
712 get_absolute_rl(right
, &rl
);
713 rl
= cast_rl(get_type(left
), rl
);
715 rl
= alloc_whole_rl(get_type(left
));
718 set_extra_array_mod(left
, alloc_estate_rl(rl
));
721 static void match_untracked_array(struct expression
*call
, int param
)
723 struct expression
*arg
;
725 arg
= get_argument_from_call_expr(call
->args
, param
);
726 arg
= strip_expr(arg
);
728 clear_array_states(arg
);
731 static void match_vanilla_assign(struct expression
*left
, struct expression
*right
)
733 struct range_list
*orig_rl
= NULL
;
734 struct range_list
*rl
= NULL
;
735 struct symbol
*right_sym
;
736 struct symbol
*left_type
;
737 struct symbol
*right_type
;
738 char *right_name
= NULL
;
742 struct smatch_state
*state
;
748 save_chunk_info(left
, right
);
750 name
= expr_to_var_sym(left
, &sym
);
753 do_array_assign(left
, '=', right
);
757 left_type
= get_type(left
);
758 right_type
= get_type(right
);
760 right_name
= expr_to_var_sym(right
, &right_sym
);
762 if (!__in_fake_assign
&&
763 !(right
->type
== EXPR_PREOP
&& right
->op
== '&') &&
764 right_name
&& right_sym
&&
765 values_fit_type(left
, right
) &&
766 !has_symbol(right
, sym
)) {
767 set_equiv(left
, right
);
771 if (is_pointer(right
) && get_address_rl(right
, &rl
)) {
772 state
= alloc_estate_rl(rl
);
776 comparison
= get_comparison(left
, right
);
778 comparison
= flip_comparison(comparison
);
779 get_implied_rl(left
, &orig_rl
);
782 if (get_implied_rl(right
, &rl
)) {
783 rl
= cast_rl(left_type
, rl
);
785 filter_by_comparison(&rl
, comparison
, orig_rl
);
786 state
= alloc_estate_rl(rl
);
787 if (get_hard_max(right
, &max
)) {
788 estate_set_hard_max(state
);
789 estate_set_fuzzy_max(state
, max
);
792 rl
= alloc_whole_rl(right_type
);
793 rl
= cast_rl(left_type
, rl
);
795 filter_by_comparison(&rl
, comparison
, orig_rl
);
796 state
= alloc_estate_rl(rl
);
800 set_extra_mod(name
, sym
, state
);
802 free_string(right_name
);
805 static int op_remove_assign(int op
)
808 case SPECIAL_ADD_ASSIGN
:
810 case SPECIAL_SUB_ASSIGN
:
812 case SPECIAL_MUL_ASSIGN
:
814 case SPECIAL_DIV_ASSIGN
:
816 case SPECIAL_MOD_ASSIGN
:
818 case SPECIAL_AND_ASSIGN
:
820 case SPECIAL_OR_ASSIGN
:
822 case SPECIAL_XOR_ASSIGN
:
824 case SPECIAL_SHL_ASSIGN
:
825 return SPECIAL_LEFTSHIFT
;
826 case SPECIAL_SHR_ASSIGN
:
827 return SPECIAL_RIGHTSHIFT
;
833 static void match_assign(struct expression
*expr
)
835 struct range_list
*rl
= NULL
;
836 struct expression
*left
;
837 struct expression
*right
;
838 struct expression
*binop_expr
;
839 struct symbol
*left_type
;
840 struct symbol
*right_type
;
843 sval_t left_min
, left_max
;
844 sval_t right_min
, right_max
;
845 sval_t res_min
, res_max
;
847 left
= strip_expr(expr
->left
);
849 right
= strip_parens(expr
->right
);
850 if (right
->type
== EXPR_CALL
&& sym_name_is("__builtin_expect", right
->fn
))
851 right
= get_argument_from_call_expr(right
->args
, 0);
852 while (right
->type
== EXPR_ASSIGNMENT
&& right
->op
== '=')
853 right
= strip_parens(right
->left
);
855 if (expr
->op
== '=' && is_condition(expr
->right
))
856 return; /* handled in smatch_condition.c */
857 if (expr
->op
== '=' && right
->type
== EXPR_CALL
)
858 return; /* handled in smatch_function_hooks.c */
859 if (expr
->op
== '=') {
860 match_vanilla_assign(left
, right
);
864 name
= expr_to_var_sym(left
, &sym
);
868 left_type
= get_type(left
);
869 right_type
= get_type(right
);
871 res_min
= sval_type_min(left_type
);
872 res_max
= sval_type_max(left_type
);
875 case SPECIAL_ADD_ASSIGN
:
876 get_absolute_max(left
, &left_max
);
877 get_absolute_max(right
, &right_max
);
878 if (sval_binop_overflows(left_max
, '+', right_max
))
880 if (get_implied_min(left
, &left_min
) &&
881 !sval_is_negative_min(left_min
) &&
882 get_implied_min(right
, &right_min
) &&
883 !sval_is_negative_min(right_min
)) {
884 res_min
= sval_binop(left_min
, '+', right_min
);
885 res_min
= sval_cast(right_type
, res_min
);
887 if (inside_loop()) /* we are assuming loops don't lead to wrapping */
889 res_max
= sval_binop(left_max
, '+', right_max
);
890 res_max
= sval_cast(right_type
, res_max
);
892 case SPECIAL_SUB_ASSIGN
:
893 if (get_implied_max(left
, &left_max
) &&
894 !sval_is_max(left_max
) &&
895 get_implied_min(right
, &right_min
) &&
896 !sval_is_min(right_min
)) {
897 res_max
= sval_binop(left_max
, '-', right_min
);
898 res_max
= sval_cast(right_type
, res_max
);
902 if (get_implied_min(left
, &left_min
) &&
903 !sval_is_min(left_min
) &&
904 get_implied_max(right
, &right_max
) &&
905 !sval_is_max(right_max
)) {
906 res_min
= sval_binop(left_min
, '-', right_max
);
907 res_min
= sval_cast(right_type
, res_min
);
910 case SPECIAL_AND_ASSIGN
:
911 case SPECIAL_MOD_ASSIGN
:
912 case SPECIAL_SHL_ASSIGN
:
913 case SPECIAL_SHR_ASSIGN
:
914 case SPECIAL_OR_ASSIGN
:
915 case SPECIAL_XOR_ASSIGN
:
916 case SPECIAL_MUL_ASSIGN
:
917 case SPECIAL_DIV_ASSIGN
:
918 binop_expr
= binop_expression(expr
->left
,
919 op_remove_assign(expr
->op
),
921 if (get_absolute_rl(binop_expr
, &rl
)) {
922 rl
= cast_rl(left_type
, rl
);
923 set_extra_mod(name
, sym
, alloc_estate_rl(rl
));
928 rl
= cast_rl(left_type
, alloc_rl(res_min
, res_max
));
929 set_extra_mod(name
, sym
, alloc_estate_rl(rl
));
934 static struct smatch_state
*increment_state(struct smatch_state
*state
)
936 sval_t min
= estate_min(state
);
937 sval_t max
= estate_max(state
);
939 if (!estate_rl(state
))
943 max
= sval_type_max(max
.type
);
945 if (!sval_is_min(min
) && !sval_is_max(min
))
947 if (!sval_is_min(max
) && !sval_is_max(max
))
949 return alloc_estate_range(min
, max
);
952 static struct smatch_state
*decrement_state(struct smatch_state
*state
)
954 sval_t min
= estate_min(state
);
955 sval_t max
= estate_max(state
);
957 if (!estate_rl(state
))
961 min
= sval_type_min(min
.type
);
963 if (!sval_is_min(min
) && !sval_is_max(min
))
965 if (!sval_is_min(max
) && !sval_is_max(max
))
967 return alloc_estate_range(min
, max
);
970 static void unop_expr(struct expression
*expr
)
972 struct smatch_state
*state
;
974 if (expr
->smatch_flags
& Handled
)
978 case SPECIAL_INCREMENT
:
979 state
= get_state_expr(SMATCH_EXTRA
, expr
->unop
);
980 state
= increment_state(state
);
982 state
= alloc_estate_whole(get_type(expr
));
983 set_extra_expr_mod(expr
->unop
, state
);
985 case SPECIAL_DECREMENT
:
986 state
= get_state_expr(SMATCH_EXTRA
, expr
->unop
);
987 state
= decrement_state(state
);
989 state
= alloc_estate_whole(get_type(expr
));
990 set_extra_expr_mod(expr
->unop
, state
);
997 static void asm_expr(struct statement
*stmt
)
1000 struct expression
*expr
;
1001 struct symbol
*type
;
1004 FOR_EACH_PTR(stmt
->asm_outputs
, expr
) {
1006 case 0: /* identifier */
1007 case 1: /* constraint */
1010 case 2: /* expression */
1012 type
= get_type(strip_expr(expr
));
1013 set_extra_expr_mod(expr
, alloc_estate_whole(type
));
1016 } END_FOR_EACH_PTR(expr
);
1019 static void check_dereference(struct expression
*expr
)
1021 if (outside_of_function())
1023 set_extra_expr_nomod(expr
, alloc_estate_range(valid_ptr_min_sval
, valid_ptr_max_sval
));
1026 static void match_dereferences(struct expression
*expr
)
1028 if (expr
->type
!= EXPR_PREOP
)
1030 check_dereference(expr
->unop
);
1033 static void match_pointer_as_array(struct expression
*expr
)
1035 if (!is_array(expr
))
1037 check_dereference(get_array_base(expr
));
1040 static void set_param_dereferenced(struct expression
*arg
, char *key
, char *unused
)
1045 name
= get_variable_from_key(arg
, key
, &sym
);
1049 set_extra_nomod(name
, sym
, alloc_estate_range(valid_ptr_min_sval
, valid_ptr_max_sval
));
1055 static sval_t
add_one(sval_t sval
)
1061 static sval_t
sub_one(sval_t sval
)
1067 static int handle_postop_inc(struct expression
*left
, int op
, struct expression
*right
)
1069 struct statement
*stmt
;
1070 struct expression
*cond
;
1071 struct smatch_state
*true_state
, *false_state
;
1076 * If we're decrementing here then that's a canonical while count down
1077 * so it's handled already. We're only handling loops like:
1079 * do { ... } while (i++ < 3);
1082 if (left
->type
!= EXPR_POSTOP
|| left
->op
!= SPECIAL_INCREMENT
)
1085 stmt
= __cur_stmt
->parent
;
1088 if (stmt
->type
== STMT_COMPOUND
)
1089 stmt
= stmt
->parent
;
1090 if (!stmt
|| stmt
->type
!= STMT_ITERATOR
|| !stmt
->iterator_post_condition
)
1093 cond
= strip_expr(stmt
->iterator_post_condition
);
1094 if (cond
->type
!= EXPR_COMPARE
|| cond
->op
!= op
)
1096 if (left
!= strip_expr(cond
->left
) || right
!= strip_expr(cond
->right
))
1099 if (!get_implied_value(left
->unop
, &start
))
1101 if (!get_implied_value(right
, &limit
))
1104 if (sval_cmp(start
, limit
) > 0)
1109 case SPECIAL_UNSIGNED_LT
:
1112 case SPECIAL_UNSIGNED_LTE
:
1113 limit
= add_one(limit
);
1119 true_state
= alloc_estate_range(add_one(start
), limit
);
1120 false_state
= alloc_estate_range(add_one(limit
), add_one(limit
));
1122 /* Currently we just discard the false state but when two passes is
1123 * implimented correctly then it will use it.
1126 set_extra_expr_true_false(left
->unop
, true_state
, false_state
);
1131 static void handle_comparison_rl(struct range_list
*left_orig
, int op
, struct range_list
*right_orig
,
1132 struct range_list
**left_true_rl
, struct range_list
**left_false_rl
,
1133 struct range_list
**right_true_rl
, struct range_list
**right_false_rl
)
1135 struct range_list
*left_true
, *left_false
;
1136 struct range_list
*right_true
, *right_false
;
1139 min
= sval_type_min(rl_type(left_orig
));
1140 max
= sval_type_max(rl_type(left_orig
));
1142 left_true
= clone_rl(left_orig
);
1143 left_false
= clone_rl(left_orig
);
1144 right_true
= clone_rl(right_orig
);
1145 right_false
= clone_rl(right_orig
);
1149 case SPECIAL_UNSIGNED_LT
:
1150 left_true
= remove_range(left_orig
, rl_max(right_orig
), max
);
1151 if (!sval_is_min(rl_min(right_orig
))) {
1152 left_false
= remove_range(left_orig
, min
, sub_one(rl_min(right_orig
)));
1155 right_true
= remove_range(right_orig
, min
, rl_min(left_orig
));
1156 if (!sval_is_max(rl_max(left_orig
)))
1157 right_false
= remove_range(right_orig
, add_one(rl_max(left_orig
)), max
);
1159 case SPECIAL_UNSIGNED_LTE
:
1161 if (!sval_is_max(rl_max(right_orig
)))
1162 left_true
= remove_range(left_orig
, add_one(rl_max(right_orig
)), max
);
1163 left_false
= remove_range(left_orig
, min
, rl_min(right_orig
));
1165 if (!sval_is_min(rl_min(left_orig
)))
1166 right_true
= remove_range(right_orig
, min
, sub_one(rl_min(left_orig
)));
1167 right_false
= remove_range(right_orig
, rl_max(left_orig
), max
);
1169 if (sval_cmp(rl_min(left_orig
), rl_min(right_orig
)) == 0)
1170 left_false
= remove_range(left_false
, rl_min(left_orig
), rl_min(left_orig
));
1171 if (sval_cmp(rl_max(left_orig
), rl_max(right_orig
)) == 0)
1172 right_false
= remove_range(right_false
, rl_max(left_orig
), rl_max(left_orig
));
1175 if (!sval_is_max(rl_max(right_orig
))) {
1176 left_true
= remove_range(left_true
, add_one(rl_max(right_orig
)), max
);
1178 if (!sval_is_min(rl_min(right_orig
))) {
1179 left_true
= remove_range(left_true
, min
, sub_one(rl_min(right_orig
)));
1181 if (sval_cmp(rl_min(right_orig
), rl_max(right_orig
)) == 0)
1182 left_false
= remove_range(left_orig
, rl_min(right_orig
), rl_min(right_orig
));
1184 if (!sval_is_max(rl_max(left_orig
)))
1185 right_true
= remove_range(right_true
, add_one(rl_max(left_orig
)), max
);
1186 if (!sval_is_min(rl_min(left_orig
)))
1187 right_true
= remove_range(right_true
, min
, sub_one(rl_min(left_orig
)));
1188 if (sval_cmp(rl_min(left_orig
), rl_max(left_orig
)) == 0)
1189 right_false
= remove_range(right_orig
, rl_min(left_orig
), rl_min(left_orig
));
1191 case SPECIAL_UNSIGNED_GTE
:
1193 if (!sval_is_min(rl_min(right_orig
)))
1194 left_true
= remove_range(left_orig
, min
, sub_one(rl_min(right_orig
)));
1195 left_false
= remove_range(left_orig
, rl_max(right_orig
), max
);
1197 if (!sval_is_max(rl_max(left_orig
)))
1198 right_true
= remove_range(right_orig
, add_one(rl_max(left_orig
)), max
);
1199 right_false
= remove_range(right_orig
, min
, rl_min(left_orig
));
1201 if (sval_cmp(rl_min(left_orig
), rl_min(right_orig
)) == 0)
1202 right_false
= remove_range(right_false
, rl_min(left_orig
), rl_min(left_orig
));
1203 if (sval_cmp(rl_max(left_orig
), rl_max(right_orig
)) == 0)
1204 left_false
= remove_range(left_false
, rl_max(left_orig
), rl_max(left_orig
));
1207 case SPECIAL_UNSIGNED_GT
:
1208 left_true
= remove_range(left_orig
, min
, rl_min(right_orig
));
1209 if (!sval_is_max(rl_max(right_orig
)))
1210 left_false
= remove_range(left_orig
, add_one(rl_max(right_orig
)), max
);
1212 right_true
= remove_range(right_orig
, rl_max(left_orig
), max
);
1213 if (!sval_is_min(rl_min(left_orig
)))
1214 right_false
= remove_range(right_orig
, min
, sub_one(rl_min(left_orig
)));
1216 case SPECIAL_NOTEQUAL
:
1217 if (!sval_is_max(rl_max(right_orig
)))
1218 left_false
= remove_range(left_false
, add_one(rl_max(right_orig
)), max
);
1219 if (!sval_is_min(rl_min(right_orig
)))
1220 left_false
= remove_range(left_false
, min
, sub_one(rl_min(right_orig
)));
1221 if (sval_cmp(rl_min(right_orig
), rl_max(right_orig
)) == 0)
1222 left_true
= remove_range(left_orig
, rl_min(right_orig
), rl_min(right_orig
));
1224 if (!sval_is_max(rl_max(left_orig
)))
1225 right_false
= remove_range(right_false
, add_one(rl_max(left_orig
)), max
);
1226 if (!sval_is_min(rl_min(left_orig
)))
1227 right_false
= remove_range(right_false
, min
, sub_one(rl_min(left_orig
)));
1228 if (sval_cmp(rl_min(left_orig
), rl_max(left_orig
)) == 0)
1229 right_true
= remove_range(right_orig
, rl_min(left_orig
), rl_min(left_orig
));
1232 sm_msg("internal error: unhandled comparison %d", op
);
1237 *left_true_rl
= left_true
;
1238 *left_false_rl
= left_false
;
1240 if (right_true_rl
) {
1241 *right_true_rl
= right_true
;
1242 *right_false_rl
= right_false
;
1246 static void handle_comparison(struct symbol
*type
, struct expression
*left
, int op
, struct expression
*right
)
1248 struct range_list
*left_orig
;
1249 struct range_list
*left_true
;
1250 struct range_list
*left_false
;
1251 struct range_list
*right_orig
;
1252 struct range_list
*right_true
;
1253 struct range_list
*right_false
;
1254 struct smatch_state
*left_true_state
;
1255 struct smatch_state
*left_false_state
;
1256 struct smatch_state
*right_true_state
;
1257 struct smatch_state
*right_false_state
;
1258 sval_t dummy
, hard_max
;
1259 int left_postop
= 0;
1260 int right_postop
= 0;
1262 if (left
->op
== SPECIAL_INCREMENT
|| left
->op
== SPECIAL_DECREMENT
) {
1263 if (left
->type
== EXPR_POSTOP
) {
1264 left
->smatch_flags
|= Handled
;
1265 left_postop
= left
->op
;
1266 if (handle_postop_inc(left
, op
, right
))
1269 left
= strip_parens(left
->unop
);
1271 while (left
->type
== EXPR_ASSIGNMENT
)
1272 left
= strip_parens(left
->left
);
1274 if (right
->op
== SPECIAL_INCREMENT
|| right
->op
== SPECIAL_DECREMENT
) {
1275 if (right
->type
== EXPR_POSTOP
) {
1276 right
->smatch_flags
|= Handled
;
1277 right_postop
= right
->op
;
1279 right
= strip_parens(right
->unop
);
1282 get_real_absolute_rl(left
, &left_orig
);
1283 left_orig
= cast_rl(type
, left_orig
);
1285 get_real_absolute_rl(right
, &right_orig
);
1286 right_orig
= cast_rl(type
, right_orig
);
1288 handle_comparison_rl(left_orig
, op
, right_orig
, &left_true
, &left_false
, &right_true
, &right_false
);
1290 left_true
= rl_truncate_cast(get_type(strip_expr(left
)), left_true
);
1291 left_false
= rl_truncate_cast(get_type(strip_expr(left
)), left_false
);
1292 right_true
= rl_truncate_cast(get_type(strip_expr(right
)), right_true
);
1293 right_false
= rl_truncate_cast(get_type(strip_expr(right
)), right_false
);
1295 if (!left_true
|| !left_false
) {
1296 struct range_list
*tmp_true
, *tmp_false
;
1298 handle_comparison_rl(alloc_whole_rl(type
), op
, right_orig
, &tmp_true
, &tmp_false
, NULL
, NULL
);
1299 tmp_true
= rl_truncate_cast(get_type(strip_expr(left
)), tmp_true
);
1300 tmp_false
= rl_truncate_cast(get_type(strip_expr(left
)), tmp_false
);
1301 if (tmp_true
&& tmp_false
)
1302 __save_imaginary_state(left
, tmp_true
, tmp_false
);
1305 if (!right_true
|| !right_false
) {
1306 struct range_list
*tmp_true
, *tmp_false
;
1308 handle_comparison_rl(alloc_whole_rl(type
), op
, right_orig
, NULL
, NULL
, &tmp_true
, &tmp_false
);
1309 tmp_true
= rl_truncate_cast(get_type(strip_expr(right
)), tmp_true
);
1310 tmp_false
= rl_truncate_cast(get_type(strip_expr(right
)), tmp_false
);
1311 if (tmp_true
&& tmp_false
)
1312 __save_imaginary_state(right
, tmp_true
, tmp_false
);
1315 left_true_state
= alloc_estate_rl(left_true
);
1316 left_false_state
= alloc_estate_rl(left_false
);
1317 right_true_state
= alloc_estate_rl(right_true
);
1318 right_false_state
= alloc_estate_rl(right_false
);
1322 case SPECIAL_UNSIGNED_LT
:
1323 case SPECIAL_UNSIGNED_LTE
:
1325 if (get_hard_max(right
, &dummy
))
1326 estate_set_hard_max(left_true_state
);
1327 if (get_hard_max(left
, &dummy
))
1328 estate_set_hard_max(right_false_state
);
1331 case SPECIAL_UNSIGNED_GT
:
1332 case SPECIAL_UNSIGNED_GTE
:
1334 if (get_hard_max(left
, &dummy
))
1335 estate_set_hard_max(right_true_state
);
1336 if (get_hard_max(right
, &dummy
))
1337 estate_set_hard_max(left_false_state
);
1343 case SPECIAL_UNSIGNED_LT
:
1344 case SPECIAL_UNSIGNED_LTE
:
1346 if (get_hard_max(right
, &hard_max
)) {
1347 if (op
== '<' || op
== SPECIAL_UNSIGNED_LT
)
1349 estate_set_fuzzy_max(left_true_state
, hard_max
);
1351 if (get_implied_value(right
, &hard_max
)) {
1352 if (op
== SPECIAL_UNSIGNED_LTE
||
1355 estate_set_fuzzy_max(left_false_state
, hard_max
);
1357 if (get_hard_max(left
, &hard_max
)) {
1358 if (op
== SPECIAL_UNSIGNED_LTE
||
1361 estate_set_fuzzy_max(right_false_state
, hard_max
);
1363 if (get_implied_value(left
, &hard_max
)) {
1364 if (op
== '<' || op
== SPECIAL_UNSIGNED_LT
)
1366 estate_set_fuzzy_max(right_true_state
, hard_max
);
1370 case SPECIAL_UNSIGNED_GT
:
1371 case SPECIAL_UNSIGNED_GTE
:
1373 if (get_hard_max(left
, &hard_max
)) {
1374 if (op
== '>' || op
== SPECIAL_UNSIGNED_GT
)
1376 estate_set_fuzzy_max(right_true_state
, hard_max
);
1378 if (get_implied_value(left
, &hard_max
)) {
1379 if (op
== SPECIAL_UNSIGNED_GTE
||
1382 estate_set_fuzzy_max(right_false_state
, hard_max
);
1384 if (get_hard_max(right
, &hard_max
)) {
1385 if (op
== SPECIAL_UNSIGNED_LTE
||
1388 estate_set_fuzzy_max(left_false_state
, hard_max
);
1390 if (get_implied_value(right
, &hard_max
)) {
1392 op
== SPECIAL_UNSIGNED_GT
)
1394 estate_set_fuzzy_max(left_true_state
, hard_max
);
1398 if (get_hard_max(left
, &hard_max
))
1399 estate_set_fuzzy_max(right_true_state
, hard_max
);
1400 if (get_hard_max(right
, &hard_max
))
1401 estate_set_fuzzy_max(left_true_state
, hard_max
);
1405 if (get_hard_max(left
, &hard_max
)) {
1406 estate_set_hard_max(left_true_state
);
1407 estate_set_hard_max(left_false_state
);
1409 if (get_hard_max(right
, &hard_max
)) {
1410 estate_set_hard_max(right_true_state
);
1411 estate_set_hard_max(right_false_state
);
1414 if (left_postop
== SPECIAL_INCREMENT
) {
1415 left_true_state
= increment_state(left_true_state
);
1416 left_false_state
= increment_state(left_false_state
);
1418 if (left_postop
== SPECIAL_DECREMENT
) {
1419 left_true_state
= decrement_state(left_true_state
);
1420 left_false_state
= decrement_state(left_false_state
);
1422 if (right_postop
== SPECIAL_INCREMENT
) {
1423 right_true_state
= increment_state(right_true_state
);
1424 right_false_state
= increment_state(right_false_state
);
1426 if (right_postop
== SPECIAL_DECREMENT
) {
1427 right_true_state
= decrement_state(right_true_state
);
1428 right_false_state
= decrement_state(right_false_state
);
1431 if (estate_rl(left_true_state
) && estates_equiv(left_true_state
, left_false_state
)) {
1432 left_true_state
= NULL
;
1433 left_false_state
= NULL
;
1436 if (estate_rl(right_true_state
) && estates_equiv(right_true_state
, right_false_state
)) {
1437 right_true_state
= NULL
;
1438 right_false_state
= NULL
;
1441 set_extra_expr_true_false(left
, left_true_state
, left_false_state
);
1442 set_extra_expr_true_false(right
, right_true_state
, right_false_state
);
1445 static int is_simple_math(struct expression
*expr
)
1449 if (expr
->type
!= EXPR_BINOP
)
1460 static void move_known_values(struct expression
**left_p
, struct expression
**right_p
)
1462 struct expression
*left
= *left_p
;
1463 struct expression
*right
= *right_p
;
1466 if (get_implied_value(left
, &sval
)) {
1467 if (!is_simple_math(right
))
1469 if (right
->op
== '*') {
1472 if (!get_value(right
->right
, &divisor
))
1474 if (divisor
.value
== 0 && sval
.value
% divisor
.value
)
1476 *left_p
= binop_expression(left
, invert_op(right
->op
), right
->right
);
1477 *right_p
= right
->left
;
1480 if (right
->op
== '+' && get_value(right
->left
, &sval
)) {
1481 *left_p
= binop_expression(left
, invert_op(right
->op
), right
->left
);
1482 *right_p
= right
->right
;
1485 if (get_value(right
->right
, &sval
)) {
1486 *left_p
= binop_expression(left
, invert_op(right
->op
), right
->right
);
1487 *right_p
= right
->left
;
1492 if (get_implied_value(right
, &sval
)) {
1493 if (!is_simple_math(left
))
1495 if (left
->op
== '*') {
1498 if (!get_value(left
->right
, &divisor
))
1500 if (divisor
.value
== 0 && sval
.value
% divisor
.value
)
1502 *right_p
= binop_expression(right
, invert_op(left
->op
), left
->right
);
1503 *left_p
= left
->left
;
1506 if (left
->op
== '+' && get_value(left
->left
, &sval
)) {
1507 *right_p
= binop_expression(right
, invert_op(left
->op
), left
->left
);
1508 *left_p
= left
->right
;
1512 if (get_value(left
->right
, &sval
)) {
1513 *right_p
= binop_expression(right
, invert_op(left
->op
), left
->right
);
1514 *left_p
= left
->left
;
1521 static int match_func_comparison(struct expression
*expr
)
1523 struct expression
*left
= strip_expr(expr
->left
);
1524 struct expression
*right
= strip_expr(expr
->right
);
1528 * fixme: think about this harder. We should always be trying to limit
1529 * the non-call side as well. If we can't determine the limitter does
1530 * that mean we aren't querying the database and are missing important
1534 if (left
->type
== EXPR_CALL
) {
1535 if (get_implied_value(left
, &sval
)) {
1536 handle_comparison(get_type(expr
), left
, expr
->op
, right
);
1539 function_comparison(left
, expr
->op
, right
);
1543 if (right
->type
== EXPR_CALL
) {
1544 if (get_implied_value(right
, &sval
)) {
1545 handle_comparison(get_type(expr
), left
, expr
->op
, right
);
1548 function_comparison(left
, expr
->op
, right
);
1555 static void match_comparison(struct expression
*expr
)
1557 struct expression
*left_orig
= strip_parens(expr
->left
);
1558 struct expression
*right_orig
= strip_parens(expr
->right
);
1559 struct expression
*left
, *right
;
1560 struct expression
*prev
;
1561 struct symbol
*type
;
1563 if (match_func_comparison(expr
))
1566 type
= get_type(expr
);
1568 type
= &llong_ctype
;
1572 move_known_values(&left
, &right
);
1573 handle_comparison(type
, left
, expr
->op
, right
);
1575 prev
= get_assigned_expr(left_orig
);
1576 if (is_simple_math(prev
) && has_variable(prev
, left_orig
) == 0) {
1579 move_known_values(&left
, &right
);
1580 handle_comparison(type
, left
, expr
->op
, right
);
1583 prev
= get_assigned_expr(right_orig
);
1584 if (is_simple_math(prev
) && has_variable(prev
, right_orig
) == 0) {
1587 move_known_values(&left
, &right
);
1588 handle_comparison(type
, left
, expr
->op
, right
);
1592 static void handle_AND_condition(struct expression
*expr
)
1594 struct range_list
*rl
= NULL
;
1597 if (get_implied_value(expr
->left
, &known
) && known
.value
> 0) {
1599 get_absolute_rl(expr
->right
, &rl
);
1600 rl
= remove_range(rl
, sval_type_val(known
.type
, 0), known
);
1601 set_extra_expr_true_false(expr
->right
, alloc_estate_rl(rl
), NULL
);
1605 if (get_implied_value(expr
->right
, &known
) && known
.value
> 0) {
1607 get_absolute_rl(expr
->left
, &rl
);
1608 rl
= remove_range(rl
, sval_type_val(known
.type
, 0), known
);
1609 set_extra_expr_true_false(expr
->left
, alloc_estate_rl(rl
), NULL
);
1614 /* this is actually hooked from smatch_implied.c... it's hacky, yes */
1615 void __extra_match_condition(struct expression
*expr
)
1617 struct smatch_state
*pre_state
;
1618 struct smatch_state
*true_state
;
1619 struct smatch_state
*false_state
;
1621 expr
= strip_expr(expr
);
1622 switch (expr
->type
) {
1624 function_comparison(expr
, SPECIAL_NOTEQUAL
, zero_expr());
1631 zero
= sval_blank(expr
);
1634 pre_state
= get_extra_state(expr
);
1635 true_state
= estate_filter_sval(pre_state
, zero
);
1636 if (possibly_true(expr
, SPECIAL_EQUAL
, zero_expr()))
1637 false_state
= alloc_estate_sval(zero
);
1639 false_state
= alloc_estate_empty();
1640 set_extra_expr_true_false(expr
, true_state
, false_state
);
1644 match_comparison(expr
);
1646 case EXPR_ASSIGNMENT
:
1647 __extra_match_condition(expr
->left
);
1650 if (expr
->op
== '&')
1651 handle_AND_condition(expr
);
1656 static void assume_indexes_are_valid(struct expression
*expr
)
1658 struct expression
*array_expr
;
1660 struct expression
*offset
;
1661 struct symbol
*offset_type
;
1662 struct range_list
*rl_before
;
1663 struct range_list
*rl_after
;
1664 struct range_list
*filter
= NULL
;
1667 expr
= strip_expr(expr
);
1668 if (!is_array(expr
))
1671 offset
= get_array_offset(expr
);
1672 offset_type
= get_type(offset
);
1673 if (offset_type
&& type_signed(offset_type
)) {
1674 filter
= alloc_rl(sval_type_min(offset_type
),
1675 sval_type_val(offset_type
, -1));
1678 array_expr
= get_array_base(expr
);
1679 array_size
= get_real_array_size(array_expr
);
1680 if (array_size
> 1) {
1681 size
= sval_type_val(offset_type
, array_size
);
1682 add_range(&filter
, size
, sval_type_max(offset_type
));
1687 get_absolute_rl(offset
, &rl_before
);
1688 rl_after
= rl_filter(rl_before
, filter
);
1689 if (rl_equiv(rl_before
, rl_after
))
1691 set_extra_expr_nomod(offset
, alloc_estate_rl(rl_after
));
1694 /* returns 1 if it is not possible for expr to be value, otherwise returns 0 */
1695 int implied_not_equal(struct expression
*expr
, long long val
)
1697 return !possibly_false(expr
, SPECIAL_NOTEQUAL
, value_expr(val
));
1700 int implied_not_equal_name_sym(char *name
, struct symbol
*sym
, long long val
)
1702 struct smatch_state
*estate
;
1704 estate
= get_state(SMATCH_EXTRA
, name
, sym
);
1707 if (!rl_has_sval(estate_rl(estate
), sval_type_val(estate_type(estate
), 0)))
1712 int parent_is_null_var_sym(const char *name
, struct symbol
*sym
)
1717 struct smatch_state
*state
;
1719 strncpy(buf
, name
, sizeof(buf
) - 1);
1720 buf
[sizeof(buf
) - 1] = '\0';
1723 while (*start
== '*') {
1725 state
= get_state(SMATCH_EXTRA
, start
, sym
);
1728 if (!estate_rl(state
))
1730 if (estate_min(state
).value
== 0 &&
1731 estate_max(state
).value
== 0)
1736 while (*start
== '&')
1739 while ((end
= strrchr(start
, '-'))) {
1741 state
= get_state(SMATCH_EXTRA
, start
, sym
);
1744 if (estate_min(state
).value
== 0 &&
1745 estate_max(state
).value
== 0)
1751 int parent_is_null(struct expression
*expr
)
1757 expr
= strip_expr(expr
);
1758 var
= expr_to_var_sym(expr
, &sym
);
1761 ret
= parent_is_null_var_sym(var
, sym
);
1767 static int param_used_callback(void *found
, int argc
, char **argv
, char **azColName
)
1773 static int filter_unused_kzalloc_info(struct expression
*call
, int param
, char *printed_name
, struct sm_state
*sm
)
1778 /* for function pointers assume everything is used */
1779 if (call
->fn
->type
!= EXPR_SYMBOL
)
1783 * kzalloc() information is treated as special because so there is just
1784 * a lot of stuff initialized to zero and it makes building the database
1785 * take hours and hours.
1787 * In theory, we should just remove this line and not pass any unused
1788 * information, but I'm not sure enough that this code works so I want
1789 * to hold off on that for now.
1791 if (!estate_get_single_value(sm
->state
, &sval
) || sval
.value
!= 0)
1794 run_sql(¶m_used_callback
, &found
,
1795 "select * from call_implies where %s and type = %d and parameter = %d and key = '%s';",
1796 get_static_filter(call
->fn
->symbol
), PARAM_USED
, param
, printed_name
);
1800 /* If the database is not built yet, then assume everything is used */
1801 run_sql(¶m_used_callback
, &found
,
1802 "select * from call_implies where %s and type = %d;",
1803 get_static_filter(call
->fn
->symbol
), PARAM_USED
);
1810 static void struct_member_callback(struct expression
*call
, int param
, char *printed_name
, struct sm_state
*sm
)
1812 if (estate_is_whole(sm
->state
))
1814 if (filter_unused_kzalloc_info(call
, param
, printed_name
, sm
))
1816 sql_insert_caller_info(call
, PARAM_VALUE
, param
, printed_name
, sm
->state
->name
);
1817 if (estate_has_fuzzy_max(sm
->state
))
1818 sql_insert_caller_info(call
, FUZZY_MAX
, param
, printed_name
,
1819 sval_to_str(estate_get_fuzzy_max(sm
->state
)));
1822 static void returned_struct_members(int return_id
, char *return_ranges
, struct expression
*expr
)
1824 struct symbol
*returned_sym
;
1825 struct sm_state
*sm
;
1826 const char *param_name
;
1830 returned_sym
= expr_to_sym(expr
);
1834 FOR_EACH_MY_SM(my_id
, __get_cur_stree(), sm
) {
1835 if (!estate_rl(sm
->state
))
1837 if (returned_sym
!= sm
->sym
)
1840 param_name
= get_param_name(sm
);
1843 if (strcmp(param_name
, "$") == 0)
1845 compare_str
= name_sym_to_param_comparison(sm
->name
, sm
->sym
);
1846 if (!compare_str
&& estate_is_whole(sm
->state
))
1848 snprintf(buf
, sizeof(buf
), "%s%s", sm
->state
->name
, compare_str
?: "");
1850 sql_insert_return_states(return_id
, return_ranges
, PARAM_VALUE
,
1851 -1, param_name
, buf
);
1852 } END_FOR_EACH_SM(sm
);
1855 static void db_limited_before(void)
1857 unmatched_stree
= clone_stree(__get_cur_stree());
1860 static void db_limited_after(void)
1862 free_stree(&unmatched_stree
);
1865 static void db_param_limit_filter(struct expression
*expr
, int param
, char *key
, char *value
, enum info_type op
)
1867 struct expression
*arg
;
1870 struct sm_state
*sm
;
1871 struct symbol
*compare_type
, *var_type
;
1872 struct range_list
*rl
;
1873 struct range_list
*limit
;
1874 struct range_list
*new;
1876 while (expr
->type
== EXPR_ASSIGNMENT
)
1877 expr
= strip_expr(expr
->right
);
1878 if (expr
->type
!= EXPR_CALL
)
1881 arg
= get_argument_from_call_expr(expr
->args
, param
);
1885 name
= get_variable_from_key(arg
, key
, &sym
);
1889 if (strcmp(key
, "$") == 0)
1890 compare_type
= get_arg_type(expr
->fn
, param
);
1892 compare_type
= get_member_type_from_key(arg
, key
);
1894 sm
= get_sm_state(SMATCH_EXTRA
, name
, sym
);
1896 rl
= estate_rl(sm
->state
);
1898 rl
= alloc_whole_rl(compare_type
);
1900 call_results_to_rl(expr
, compare_type
, value
, &limit
);
1901 new = rl_intersection(rl
, limit
);
1903 var_type
= get_member_type_from_key(arg
, key
);
1904 new = cast_rl(var_type
, new);
1906 /* We want to preserve the implications here */
1907 if (sm
&& rl_equiv(estate_rl(sm
->state
), new))
1910 if (op
== PARAM_LIMIT
)
1911 set_extra_nomod(name
, sym
, alloc_estate_rl(new));
1913 set_extra_mod(name
, sym
, alloc_estate_rl(new));
1920 static void db_param_limit(struct expression
*expr
, int param
, char *key
, char *value
)
1922 db_param_limit_filter(expr
, param
, key
, value
, PARAM_LIMIT
);
1925 static void db_param_filter(struct expression
*expr
, int param
, char *key
, char *value
)
1927 db_param_limit_filter(expr
, param
, key
, value
, PARAM_FILTER
);
1930 static void db_param_add_set(struct expression
*expr
, int param
, char *key
, char *value
, enum info_type op
)
1932 struct expression
*arg
;
1935 struct symbol
*type
;
1936 struct smatch_state
*state
;
1937 struct range_list
*new = NULL
;
1938 struct range_list
*added
= NULL
;
1940 while (expr
->type
== EXPR_ASSIGNMENT
)
1941 expr
= strip_expr(expr
->right
);
1942 if (expr
->type
!= EXPR_CALL
)
1945 arg
= get_argument_from_call_expr(expr
->args
, param
);
1948 type
= get_member_type_from_key(arg
, key
);
1949 name
= get_variable_from_key(arg
, key
, &sym
);
1953 state
= get_state(SMATCH_EXTRA
, name
, sym
);
1955 new = estate_rl(state
);
1957 call_results_to_rl(expr
, type
, value
, &added
);
1959 if (op
== PARAM_SET
)
1962 new = rl_union(new, added
);
1964 set_extra_mod(name
, sym
, alloc_estate_rl(new));
1969 static void db_param_add(struct expression
*expr
, int param
, char *key
, char *value
)
1971 db_param_add_set(expr
, param
, key
, value
, PARAM_ADD
);
1974 static void db_param_set(struct expression
*expr
, int param
, char *key
, char *value
)
1976 db_param_add_set(expr
, param
, key
, value
, PARAM_SET
);
1979 static void db_param_value(struct expression
*expr
, int param
, char *key
, char *value
)
1981 struct expression
*call
;
1984 struct symbol
*type
;
1985 struct range_list
*rl
= NULL
;
1991 while (call
->type
== EXPR_ASSIGNMENT
)
1992 call
= strip_expr(call
->right
);
1993 if (call
->type
!= EXPR_CALL
)
1996 type
= get_member_type_from_key(expr
->left
, key
);
1997 name
= get_variable_from_key(expr
->left
, key
, &sym
);
2001 call_results_to_rl(call
, type
, value
, &rl
);
2003 set_extra_mod(name
, sym
, alloc_estate_rl(rl
));
2008 static void match_call_info(struct expression
*expr
)
2010 struct smatch_state
*state
;
2011 struct range_list
*rl
= NULL
;
2012 struct expression
*arg
;
2013 struct symbol
*type
;
2016 FOR_EACH_PTR(expr
->args
, arg
) {
2017 type
= get_arg_type(expr
->fn
, i
);
2019 if (get_implied_rl(arg
, &rl
))
2020 rl
= cast_rl(type
, rl
);
2022 rl
= cast_rl(type
, alloc_whole_rl(get_type(arg
)));
2024 if (!is_whole_rl(rl
))
2025 sql_insert_caller_info(expr
, PARAM_VALUE
, i
, "$", show_rl(rl
));
2026 state
= get_state_expr(SMATCH_EXTRA
, arg
);
2027 if (estate_has_fuzzy_max(state
)) {
2028 sql_insert_caller_info(expr
, FUZZY_MAX
, i
, "$",
2029 sval_to_str(estate_get_fuzzy_max(state
)));
2032 } END_FOR_EACH_PTR(arg
);
2035 static void set_param_value(const char *name
, struct symbol
*sym
, char *key
, char *value
)
2037 struct range_list
*rl
= NULL
;
2038 struct smatch_state
*state
;
2039 struct symbol
*type
;
2042 if (strcmp(key
, "*$") == 0)
2043 snprintf(fullname
, sizeof(fullname
), "*%s", name
);
2044 else if (strncmp(key
, "$", 1) == 0)
2045 snprintf(fullname
, 256, "%s%s", name
, key
+ 1);
2049 type
= get_member_type_from_key(symbol_expression(sym
), key
);
2050 str_to_rl(type
, value
, &rl
);
2051 state
= alloc_estate_rl(rl
);
2052 set_state(SMATCH_EXTRA
, fullname
, sym
, state
);
2055 static void set_param_hard_max(const char *name
, struct symbol
*sym
, char *key
, char *value
)
2057 struct range_list
*rl
= NULL
;
2058 struct smatch_state
*state
;
2059 struct symbol
*type
;
2063 if (strcmp(key
, "*$") == 0)
2064 snprintf(fullname
, sizeof(fullname
), "*%s", name
);
2065 else if (strncmp(key
, "$", 1) == 0)
2066 snprintf(fullname
, 256, "%s%s", name
, key
+ 1);
2070 state
= get_state(SMATCH_EXTRA
, fullname
, sym
);
2073 type
= get_member_type_from_key(symbol_expression(sym
), key
);
2074 str_to_rl(type
, value
, &rl
);
2075 if (!rl_to_sval(rl
, &max
))
2077 estate_set_fuzzy_max(state
, max
);
2080 struct smatch_state
*get_extra_state(struct expression
*expr
)
2084 struct smatch_state
*ret
= NULL
;
2085 struct range_list
*rl
;
2087 if (is_pointer(expr
) && get_address_rl(expr
, &rl
))
2088 return alloc_estate_rl(rl
);
2090 name
= expr_to_known_chunk_sym(expr
, &sym
);
2094 ret
= get_state(SMATCH_EXTRA
, name
, sym
);
2100 void register_smatch_extra(int id
)
2104 add_merge_hook(my_id
, &merge_estates
);
2105 add_unmatched_state_hook(my_id
, &unmatched_state
);
2106 select_caller_info_hook(set_param_value
, PARAM_VALUE
);
2107 select_caller_info_hook(set_param_hard_max
, FUZZY_MAX
);
2108 select_return_states_before(&db_limited_before
);
2109 select_return_states_hook(PARAM_LIMIT
, &db_param_limit
);
2110 select_return_states_hook(PARAM_FILTER
, &db_param_filter
);
2111 select_return_states_hook(PARAM_ADD
, &db_param_add
);
2112 select_return_states_hook(PARAM_SET
, &db_param_set
);
2113 select_return_states_hook(PARAM_VALUE
, &db_param_value
);
2114 select_return_states_after(&db_limited_after
);
2117 static void match_link_modify(struct sm_state
*sm
, struct expression
*mod_expr
)
2119 struct var_sym_list
*links
;
2120 struct var_sym
*tmp
;
2121 struct smatch_state
*state
;
2123 links
= sm
->state
->data
;
2125 FOR_EACH_PTR(links
, tmp
) {
2126 state
= get_state(SMATCH_EXTRA
, tmp
->var
, tmp
->sym
);
2129 set_state(SMATCH_EXTRA
, tmp
->var
, tmp
->sym
, alloc_estate_whole(estate_type(state
)));
2130 } END_FOR_EACH_PTR(tmp
);
2131 set_state(link_id
, sm
->name
, sm
->sym
, &undefined
);
2134 void register_smatch_extra_links(int id
)
2139 void register_smatch_extra_late(int id
)
2141 add_merge_hook(link_id
, &merge_link_states
);
2142 add_modification_hook(link_id
, &match_link_modify
);
2143 add_hook(&match_dereferences
, DEREF_HOOK
);
2144 add_hook(&match_pointer_as_array
, OP_HOOK
);
2145 select_call_implies_hook(DEREFERENCE
, &set_param_dereferenced
);
2146 add_hook(&match_function_call
, FUNCTION_CALL_HOOK
);
2147 add_hook(&match_assign
, ASSIGNMENT_HOOK
);
2148 add_hook(&match_assign
, GLOBAL_ASSIGNMENT_HOOK
);
2149 add_hook(&unop_expr
, OP_HOOK
);
2150 add_hook(&asm_expr
, ASM_HOOK
);
2151 add_untracked_param_hook(&match_untracked_array
);
2153 add_hook(&match_call_info
, FUNCTION_CALL_HOOK
);
2154 add_member_info_callback(my_id
, struct_member_callback
);
2155 add_split_return_callback(&returned_struct_members
);
2157 add_hook(&assume_indexes_are_valid
, OP_HOOK
);