2 * Copyright (C) 2008,2009 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
21 #include "smatch_slist.h"
25 ALLOCATOR(smatch_state
, "smatch state");
26 ALLOCATOR(sm_state
, "sm state");
27 ALLOCATOR(named_stree
, "named slist");
28 __DO_ALLOCATOR(char, 1, 4, "state names", sname
);
30 static int sm_state_counter
;
32 static struct stree_stack
*all_pools
;
34 char *show_sm(struct sm_state
*sm
)
41 pos
= snprintf(buf
, sizeof(buf
), "[%s] '%s' = %s (",
42 check_name(sm
->owner
), sm
->name
, show_state(sm
->state
));
43 if (pos
> sizeof(buf
))
47 FOR_EACH_PTR(sm
->possible
, tmp
) {
49 pos
+= snprintf(buf
+ pos
, sizeof(buf
) - pos
, ", ");
50 if (pos
> sizeof(buf
))
52 pos
+= snprintf(buf
+ pos
, sizeof(buf
) - pos
, "%s",
53 show_state(tmp
->state
));
54 if (pos
> sizeof(buf
))
56 } END_FOR_EACH_PTR(tmp
);
57 snprintf(buf
+ pos
, sizeof(buf
) - pos
, ")");
62 for (i
= 0; i
< 3; i
++)
63 buf
[sizeof(buf
) - 2 - i
] = '.';
67 void __print_stree(struct stree
*stree
)
71 printf("dumping stree at %d\n", get_lineno());
72 FOR_EACH_SM(stree
, sm
) {
73 printf("%s\n", show_sm(sm
));
74 } END_FOR_EACH_SM(sm
);
78 /* NULL states go at the end to simplify merge_slist */
79 int cmp_tracker(const struct sm_state
*a
, const struct sm_state
*b
)
90 if (a
->owner
> b
->owner
)
92 if (a
->owner
< b
->owner
)
95 ret
= strcmp(a
->name
, b
->name
);
99 if (!b
->sym
&& a
->sym
)
101 if (!a
->sym
&& b
->sym
)
111 static int cmp_sm_states(const struct sm_state
*a
, const struct sm_state
*b
, int preserve
)
115 ret
= cmp_tracker(a
, b
);
119 /* todo: add hook for smatch_extra.c */
120 if (a
->state
> b
->state
)
122 if (a
->state
< b
->state
)
124 /* This is obviously a massive disgusting hack but we need to preserve
125 * the unmerged states for smatch extra because we use them in
126 * smatch_db.c. Meanwhile if we preserve all the other unmerged states
127 * then it uses a lot of memory and we don't use it. Hence this hack.
129 * Also sometimes even just preserving every possible SMATCH_EXTRA state
130 * takes too much resources so we have to cap that. Capping is probably
131 * not often a problem in real life.
133 if (a
->owner
== SMATCH_EXTRA
&& preserve
) {
136 if (a
->merged
== 1 && b
->merged
== 0)
145 static struct sm_state
*alloc_sm_state(int owner
, const char *name
,
146 struct symbol
*sym
, struct smatch_state
*state
)
148 struct sm_state
*sm_state
= __alloc_sm_state(0);
152 sm_state
->name
= alloc_sname(name
);
153 sm_state
->owner
= owner
;
155 sm_state
->state
= state
;
156 sm_state
->line
= get_lineno();
157 sm_state
->merged
= 0;
158 sm_state
->implied
= 0;
159 sm_state
->pool
= NULL
;
160 sm_state
->left
= NULL
;
161 sm_state
->right
= NULL
;
162 sm_state
->nr_children
= 1;
163 sm_state
->possible
= NULL
;
164 add_ptr_list(&sm_state
->possible
, sm_state
);
168 static struct sm_state
*alloc_state_no_name(int owner
, const char *name
,
170 struct smatch_state
*state
)
172 struct sm_state
*tmp
;
174 tmp
= alloc_sm_state(owner
, NULL
, sym
, state
);
179 int too_many_possible(struct sm_state
*sm
)
181 if (ptr_list_size((struct ptr_list
*)sm
->possible
) >= 100)
186 void add_possible_sm(struct sm_state
*to
, struct sm_state
*new)
188 struct sm_state
*tmp
;
191 if (too_many_possible(to
))
194 FOR_EACH_PTR(to
->possible
, tmp
) {
195 if (cmp_sm_states(tmp
, new, preserve
) < 0)
197 else if (cmp_sm_states(tmp
, new, preserve
) == 0) {
200 INSERT_CURRENT(new, tmp
);
203 } END_FOR_EACH_PTR(tmp
);
204 add_ptr_list(&to
->possible
, new);
207 static void copy_possibles(struct sm_state
*to
, struct sm_state
*from
)
209 struct sm_state
*tmp
;
211 FOR_EACH_PTR(from
->possible
, tmp
) {
212 add_possible_sm(to
, tmp
);
213 } END_FOR_EACH_PTR(tmp
);
216 char *alloc_sname(const char *str
)
222 tmp
= __alloc_sname(strlen(str
) + 1);
227 int out_of_memory(void)
230 * I decided to use 50M here based on trial and error.
231 * It works out OK for the kernel and so it should work
232 * for most other projects as well.
234 if (sm_state_counter
* sizeof(struct sm_state
) >= 50000000)
239 int low_on_memory(void)
241 if (sm_state_counter
* sizeof(struct sm_state
) >= 25000000)
246 static void free_sm_state(struct sm_state
*sm
)
248 free_slist(&sm
->possible
);
250 * fixme. Free the actual state.
251 * Right now we leave it until the end of the function
252 * because we don't want to double free it.
253 * Use the freelist to not double free things
257 static void free_all_sm_states(struct allocation_blob
*blob
)
259 unsigned int size
= sizeof(struct sm_state
);
260 unsigned int offset
= 0;
262 while (offset
< blob
->offset
) {
263 free_sm_state((struct sm_state
*)(blob
->data
+ offset
));
268 /* At the end of every function we free all the sm_states */
269 void free_every_single_sm_state(void)
271 struct allocator_struct
*desc
= &sm_state_allocator
;
272 struct allocation_blob
*blob
= desc
->blobs
;
275 desc
->allocations
= 0;
276 desc
->total_bytes
= 0;
277 desc
->useful_bytes
= 0;
278 desc
->freelist
= NULL
;
280 struct allocation_blob
*next
= blob
->next
;
281 free_all_sm_states(blob
);
282 blob_free(blob
, desc
->chunking
);
286 clear_smatch_state_alloc();
288 free_stack_and_strees(&all_pools
);
289 sm_state_counter
= 0;
292 struct sm_state
*clone_sm(struct sm_state
*s
)
294 struct sm_state
*ret
;
296 ret
= alloc_state_no_name(s
->owner
, s
->name
, s
->sym
, s
->state
);
297 ret
->merged
= s
->merged
;
298 ret
->implied
= s
->implied
;
300 /* clone_sm() doesn't copy the pools. Each state needs to have
302 ret
->possible
= clone_slist(s
->possible
);
304 ret
->right
= s
->right
;
305 ret
->nr_children
= s
->nr_children
;
309 int is_merged(struct sm_state
*sm
)
314 int is_implied(struct sm_state
*sm
)
319 int slist_has_state(struct state_list
*slist
, struct smatch_state
*state
)
321 struct sm_state
*tmp
;
323 FOR_EACH_PTR(slist
, tmp
) {
324 if (tmp
->state
== state
)
326 } END_FOR_EACH_PTR(tmp
);
330 struct state_list
*clone_slist(struct state_list
*from_slist
)
333 struct state_list
*to_slist
= NULL
;
335 FOR_EACH_PTR(from_slist
, sm
) {
336 add_ptr_list(&to_slist
, sm
);
337 } END_FOR_EACH_PTR(sm
);
341 struct smatch_state
*merge_states(int owner
, const char *name
,
343 struct smatch_state
*state1
,
344 struct smatch_state
*state2
)
346 struct smatch_state
*ret
;
348 if (state1
== state2
)
350 else if (__has_merge_function(owner
))
351 ret
= __client_merge_function(owner
, state1
, state2
);
352 else if (state1
== &ghost
)
354 else if (state2
== &ghost
)
356 else if (!state1
|| !state2
)
363 struct sm_state
*merge_sm_states(struct sm_state
*one
, struct sm_state
*two
)
365 struct smatch_state
*s
;
366 struct sm_state
*result
;
370 s
= merge_states(one
->owner
, one
->name
, one
->sym
, one
->state
, two
->state
);
371 result
= alloc_state_no_name(one
->owner
, one
->name
, one
->sym
, s
);
375 result
->nr_children
= one
->nr_children
+ two
->nr_children
;
376 copy_possibles(result
, one
);
377 copy_possibles(result
, two
);
380 strcmp(check_name(one
->owner
), option_debug_check
) == 0) {
381 struct sm_state
*tmp
;
384 printf("%s:%d %s() merge [%s] '%s' %s(L %d) + %s(L %d) => %s (",
385 get_filename(), get_lineno(), get_function(),
386 check_name(one
->owner
), one
->name
,
387 show_state(one
->state
), one
->line
,
388 show_state(two
->state
), two
->line
,
391 FOR_EACH_PTR(result
->possible
, tmp
) {
394 printf("%s", show_state(tmp
->state
));
395 } END_FOR_EACH_PTR(tmp
);
402 struct sm_state
*get_sm_state_stree(struct stree
*stree
, int owner
, const char *name
,
405 struct tracker tracker
= {
407 .name
= (char *)name
,
415 return avl_lookup(stree
, (struct sm_state
*)&tracker
);
418 struct smatch_state
*get_state_stree(struct stree
*stree
,
419 int owner
, const char *name
,
424 sm
= get_sm_state_stree(stree
, owner
, name
, sym
);
430 /* FIXME: this is almost exactly the same as set_sm_state_slist() */
431 void overwrite_sm_state_stree(struct stree
**stree
, struct sm_state
*new)
433 avl_insert(stree
, new);
436 void overwrite_sm_state_stree_stack(struct stree_stack
**stack
,
441 stree
= pop_stree(stack
);
442 overwrite_sm_state_stree(&stree
, sm
);
443 push_stree(stack
, stree
);
446 struct sm_state
*set_state_stree(struct stree
**stree
, int owner
, const char *name
,
447 struct symbol
*sym
, struct smatch_state
*state
)
449 struct sm_state
*new = alloc_sm_state(owner
, name
, sym
, state
);
451 avl_insert(stree
, new);
455 void set_state_stree_perm(struct stree
**stree
, int owner
, const char *name
,
456 struct symbol
*sym
, struct smatch_state
*state
)
460 sm
= malloc(sizeof(*sm
) + strlen(name
) + 1);
461 memset(sm
, 0, sizeof(*sm
));
463 sm
->name
= (char *)(sm
+ 1);
464 strcpy((char *)sm
->name
, name
);
468 overwrite_sm_state_stree(stree
, sm
);
471 void delete_state_stree(struct stree
**stree
, int owner
, const char *name
,
474 struct tracker tracker
= {
476 .name
= (char *)name
,
480 avl_remove(stree
, (struct sm_state
*)&tracker
);
483 void delete_state_stree_stack(struct stree_stack
**stack
, int owner
, const char *name
,
488 stree
= pop_stree(stack
);
489 delete_state_stree(&stree
, owner
, name
, sym
);
490 push_stree(stack
, stree
);
493 void push_stree(struct stree_stack
**stack
, struct stree
*stree
)
495 add_ptr_list(stack
, stree
);
498 struct stree
*pop_stree(struct stree_stack
**stack
)
502 stree
= last_ptr_list((struct ptr_list
*)*stack
);
503 delete_ptr_list_last((struct ptr_list
**)stack
);
507 void free_slist(struct state_list
**slist
)
509 __free_ptr_list((struct ptr_list
**)slist
);
512 void free_stree_stack(struct stree_stack
**stack
)
514 __free_ptr_list((struct ptr_list
**)stack
);
517 void free_stack_and_strees(struct stree_stack
**stree_stack
)
521 FOR_EACH_PTR(*stree_stack
, stree
) {
523 } END_FOR_EACH_PTR(stree
);
524 free_stree_stack(stree_stack
);
527 struct sm_state
*set_state_stree_stack(struct stree_stack
**stack
, int owner
, const char *name
,
528 struct symbol
*sym
, struct smatch_state
*state
)
533 stree
= pop_stree(stack
);
534 sm
= set_state_stree(&stree
, owner
, name
, sym
, state
);
535 push_stree(stack
, stree
);
541 * get_sm_state_stack() gets the state for the top slist on the stack.
543 struct sm_state
*get_sm_state_stree_stack(struct stree_stack
*stack
,
544 int owner
, const char *name
,
548 struct sm_state
*ret
;
550 stree
= pop_stree(&stack
);
551 ret
= get_sm_state_stree(stree
, owner
, name
, sym
);
552 push_stree(&stack
, stree
);
556 struct smatch_state
*get_state_stree_stack(struct stree_stack
*stack
,
557 int owner
, const char *name
,
562 sm
= get_sm_state_stree_stack(stack
, owner
, name
, sym
);
568 static void match_states_stree(struct stree
**one
, struct stree
**two
)
570 struct smatch_state
*tmp_state
;
572 struct state_list
*add_to_one
= NULL
;
573 struct state_list
*add_to_two
= NULL
;
577 avl_iter_begin(&one_iter
, *one
, FORWARD
);
578 avl_iter_begin(&two_iter
, *two
, FORWARD
);
581 if (!one_iter
.sm
&& !two_iter
.sm
)
583 if (cmp_tracker(one_iter
.sm
, two_iter
.sm
) < 0) {
584 __set_fake_cur_stree_fast(*two
);
585 tmp_state
= __client_unmatched_state_function(one_iter
.sm
);
586 __pop_fake_cur_stree_fast();
587 sm
= alloc_state_no_name(one_iter
.sm
->owner
, one_iter
.sm
->name
,
588 one_iter
.sm
->sym
, tmp_state
);
589 add_ptr_list(&add_to_two
, sm
);
590 avl_iter_next(&one_iter
);
591 } else if (cmp_tracker(one_iter
.sm
, two_iter
.sm
) == 0) {
592 avl_iter_next(&one_iter
);
593 avl_iter_next(&two_iter
);
595 __set_fake_cur_stree_fast(*one
);
596 tmp_state
= __client_unmatched_state_function(two_iter
.sm
);
597 __pop_fake_cur_stree_fast();
598 sm
= alloc_state_no_name(two_iter
.sm
->owner
, two_iter
.sm
->name
,
599 two_iter
.sm
->sym
, tmp_state
);
600 add_ptr_list(&add_to_one
, sm
);
601 avl_iter_next(&two_iter
);
605 FOR_EACH_PTR(add_to_one
, sm
) {
607 } END_FOR_EACH_PTR(sm
);
609 FOR_EACH_PTR(add_to_two
, sm
) {
611 } END_FOR_EACH_PTR(sm
);
613 free_slist(&add_to_one
);
614 free_slist(&add_to_two
);
617 static void clone_pool_havers_stree(struct stree
**stree
)
619 struct sm_state
*sm
, *tmp
;
620 struct state_list
*slist
= NULL
;
622 FOR_EACH_SM(*stree
, sm
) {
625 add_ptr_list(&slist
, tmp
);
627 } END_FOR_EACH_SM(sm
);
629 FOR_EACH_PTR(slist
, sm
) {
630 avl_insert(stree
, sm
);
631 } END_FOR_EACH_PTR(sm
);
639 * merge_slist() is called whenever paths merge, such as after
640 * an if statement. It takes the two slists and creates one.
642 static void __merge_stree(struct stree
**to
, struct stree
*stree
, int add_pool
)
644 struct stree
*results
= NULL
;
645 struct stree
*implied_one
= NULL
;
646 struct stree
*implied_two
= NULL
;
649 struct sm_state
*tmp_sm
;
654 /* merging a null and nonnull path gives you only the nonnull path */
661 *to
= clone_stree(stree
);
665 implied_one
= clone_stree(*to
);
666 implied_two
= clone_stree(stree
);
668 match_states_stree(&implied_one
, &implied_two
);
671 clone_pool_havers_stree(&implied_one
);
672 clone_pool_havers_stree(&implied_two
);
674 set_stree_id(&implied_one
, ++__stree_id
);
675 set_stree_id(&implied_two
, ++__stree_id
);
678 push_stree(&all_pools
, implied_one
);
679 push_stree(&all_pools
, implied_two
);
681 avl_iter_begin(&one_iter
, implied_one
, FORWARD
);
682 avl_iter_begin(&two_iter
, implied_two
, FORWARD
);
685 if (!one_iter
.sm
&& !two_iter
.sm
)
687 if (cmp_tracker(one_iter
.sm
, two_iter
.sm
) < 0) {
688 sm_msg("error: Internal smatch error.");
689 avl_iter_next(&one_iter
);
690 } else if (cmp_tracker(one_iter
.sm
, two_iter
.sm
) == 0) {
691 if (add_pool
&& one_iter
.sm
!= two_iter
.sm
) {
692 one_iter
.sm
->pool
= implied_one
;
693 two_iter
.sm
->pool
= implied_two
;
695 tmp_sm
= merge_sm_states(one_iter
.sm
, two_iter
.sm
);
696 avl_insert(&results
, tmp_sm
);
697 avl_iter_next(&one_iter
);
698 avl_iter_next(&two_iter
);
700 sm_msg("error: Internal smatch error.");
701 avl_iter_next(&two_iter
);
709 void merge_stree(struct stree
**to
, struct stree
*stree
)
711 __merge_stree(to
, stree
, 1);
714 void merge_stree_no_pools(struct stree
**to
, struct stree
*stree
)
716 __merge_stree(to
, stree
, 0);
720 * This is unfortunately a bit subtle... The problem is that if a
721 * state is set on one fake stree but not the other then we should
722 * look up the the original state and use that as the unset state.
723 * Fortunately, after you pop your fake stree then the cur_slist should
724 * reflect the original state.
726 void merge_fake_stree(struct stree
**to
, struct stree
*stree
)
728 struct stree
*one
= *to
;
729 struct stree
*two
= stree
;
731 struct state_list
*add_to_one
= NULL
;
732 struct state_list
*add_to_two
= NULL
;
741 *to
= clone_stree(stree
);
745 avl_iter_begin(&one_iter
, one
, FORWARD
);
746 avl_iter_begin(&two_iter
, two
, FORWARD
);
749 if (!one_iter
.sm
&& !two_iter
.sm
)
751 if (cmp_tracker(one_iter
.sm
, two_iter
.sm
) < 0) {
752 sm
= get_sm_state(one_iter
.sm
->owner
, one_iter
.sm
->name
,
755 add_ptr_list(&add_to_two
, sm
);
756 avl_iter_next(&one_iter
);
757 } else if (cmp_tracker(one_iter
.sm
, two_iter
.sm
) == 0) {
758 avl_iter_next(&one_iter
);
759 avl_iter_next(&two_iter
);
761 sm
= get_sm_state(two_iter
.sm
->owner
, two_iter
.sm
->name
,
764 add_ptr_list(&add_to_one
, sm
);
765 avl_iter_next(&two_iter
);
769 FOR_EACH_PTR(add_to_one
, sm
) {
770 avl_insert(&one
, sm
);
771 } END_FOR_EACH_PTR(sm
);
773 FOR_EACH_PTR(add_to_two
, sm
) {
774 avl_insert(&two
, sm
);
775 } END_FOR_EACH_PTR(sm
);
777 free_slist(&add_to_one
);
778 free_slist(&add_to_two
);
780 __merge_stree(&one
, two
, 1);
786 * filter_slist() removes any sm states "slist" holds in common with "filter"
788 void filter_stree(struct stree
**stree
, struct stree
*filter
)
790 struct stree
*results
= NULL
;
794 avl_iter_begin(&one_iter
, *stree
, FORWARD
);
795 avl_iter_begin(&two_iter
, filter
, FORWARD
);
797 /* FIXME: This should probably be re-written with trees in mind */
800 if (!one_iter
.sm
&& !two_iter
.sm
)
802 if (cmp_tracker(one_iter
.sm
, two_iter
.sm
) < 0) {
803 avl_insert(&results
, one_iter
.sm
);
804 avl_iter_next(&one_iter
);
805 } else if (cmp_tracker(one_iter
.sm
, two_iter
.sm
) == 0) {
806 if (one_iter
.sm
!= two_iter
.sm
)
807 avl_insert(&results
, one_iter
.sm
);
808 avl_iter_next(&one_iter
);
809 avl_iter_next(&two_iter
);
811 avl_iter_next(&two_iter
);
821 * and_slist_stack() pops the top two slists, overwriting the one with
822 * the other and pushing it back on the stack.
824 void and_stree_stack(struct stree_stack
**stack
)
826 struct sm_state
*tmp
;
827 struct stree
*right_stree
= pop_stree(stack
);
829 FOR_EACH_SM(right_stree
, tmp
) {
830 overwrite_sm_state_stree_stack(stack
, tmp
);
831 } END_FOR_EACH_SM(tmp
);
832 free_stree(&right_stree
);
836 * or_slist_stack() is for if we have: if (foo || bar) { foo->baz;
837 * It pops the two slists from the top of the stack and merges them
838 * together in a way that preserves the things they have in common
839 * but creates a merged state for most of the rest.
840 * You could have code that had: if (foo || foo) { foo->baz;
841 * It's this function which ensures smatch does the right thing.
843 void or_stree_stack(struct stree_stack
**pre_conds
,
844 struct stree
*cur_stree
,
845 struct stree_stack
**stack
)
849 struct stree
*pre_stree
;
851 struct stree
*tmp_stree
;
853 new = pop_stree(stack
);
854 old
= pop_stree(stack
);
856 pre_stree
= pop_stree(pre_conds
);
857 push_stree(pre_conds
, clone_stree(pre_stree
));
859 res
= clone_stree(pre_stree
);
860 overwrite_stree(old
, &res
);
862 tmp_stree
= clone_stree(cur_stree
);
863 overwrite_stree(new, &tmp_stree
);
865 merge_stree(&res
, tmp_stree
);
866 filter_stree(&res
, pre_stree
);
868 push_stree(stack
, res
);
869 free_stree(&tmp_stree
);
870 free_stree(&pre_stree
);
876 * get_named_stree() is only used for gotos.
878 struct stree
**get_named_stree(struct named_stree_stack
*stack
,
881 struct named_stree
*tmp
;
883 FOR_EACH_PTR(stack
, tmp
) {
884 if (!strcmp(tmp
->name
, name
))
886 } END_FOR_EACH_PTR(tmp
);
890 /* FIXME: These parameters are in a different order from expected */
891 void overwrite_stree(struct stree
*from
, struct stree
**to
)
893 struct sm_state
*tmp
;
895 FOR_EACH_SM(from
, tmp
) {
896 overwrite_sm_state_stree(to
, tmp
);
897 } END_FOR_EACH_SM(tmp
);