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--- old/usr/src/tools/smatch/src/smatch_real_absolute.c
+++ new/usr/src/tools/smatch/src/smatch_real_absolute.c
1 1 /*
2 2 * Copyright (C) 2015 Oracle.
3 3 *
4 4 * This program is free software; you can redistribute it and/or
5 5 * modify it under the terms of the GNU General Public License
6 6 * as published by the Free Software Foundation; either version 2
7 7 * of the License, or (at your option) any later version.
8 8 *
9 9 * This program is distributed in the hope that it will be useful,
10 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 12 * GNU General Public License for more details.
13 13 *
14 14 * You should have received a copy of the GNU General Public License
15 15 * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
16 16 */
17 17
18 18 /*
19 19 * Say we have a line like:
20 20 * foo = bar / 8;
21 21 * Assume we don't know anything about bar. Well, now we know that foo is less
22 22 * than UINT_MAX / 8. Which might be useful, but it probably is misleading
23 23 * useless knowledge. Up to now we have ignored those but now we have said to
24 24 * store them.
25 25 *
26 26 * It also works if you have something like "foo = (int)(char)unknown_var;".
27 27 *
28 28 * I feel like this data doesn't have to be perfect, it just has to be better
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29 29 * than nothing and that will help eliminate some false positives.
30 30 *
31 31 */
32 32
33 33 #include "smatch.h"
34 34 #include "smatch_slist.h"
35 35 #include "smatch_extra.h"
36 36
37 37 static int my_id;
38 38
39 -static void pre_merge_hook(struct sm_state *sm)
39 +static void extra_mod_hook(const char *name, struct symbol *sym, struct expression *expr, struct smatch_state *state)
40 40 {
41 41 struct smatch_state *abs;
42 + struct range_list *rl;
43 +
44 + abs = get_state(my_id, name, sym);
45 + if (!abs || !estate_rl(abs))
46 + return;
47 + rl = rl_intersection(estate_rl(abs), estate_rl(state));
48 + set_state(my_id, name, sym, alloc_estate_rl(clone_rl(rl)));
49 +}
50 +
51 +static void pre_merge_hook(struct sm_state *cur, struct sm_state *other)
52 +{
42 53 struct smatch_state *extra;
43 54 struct range_list *rl;
44 55
45 - extra = get_state(SMATCH_EXTRA, sm->name, sm->sym);
56 + extra = get_state(SMATCH_EXTRA, cur->name, cur->sym);
46 57 if (!extra || !estate_rl(extra))
47 58 return;
48 - abs = get_state(my_id, sm->name, sm->sym);
49 - if (!abs || !estate_rl(abs)) {
50 - set_state(my_id, sm->name, sm->sym, clone_estate(extra));
59 + if (!estate_rl(cur->state)) {
60 + set_state(my_id, cur->name, cur->sym, clone_estate(extra));
51 61 return;
52 62 }
53 - rl = rl_intersection(estate_rl(abs), estate_rl(extra));
54 - set_state(my_id, sm->name, sm->sym, alloc_estate_rl(clone_rl(rl)));
63 + rl = rl_intersection(estate_rl(cur->state), estate_rl(extra));
64 + set_state(my_id, cur->name, cur->sym, alloc_estate_rl(clone_rl(rl)));
55 65 }
56 66
57 67 static struct smatch_state *empty_state(struct sm_state *sm)
58 68 {
59 69 return alloc_estate_empty();
60 70 }
61 71
62 -static void reset(struct sm_state *sm, struct expression *mod_expr)
63 -{
64 - set_state(my_id, sm->name, sm->sym, alloc_estate_whole(estate_type(sm->state)));
65 -}
66 -
67 72 static int in_iterator_pre_statement(void)
68 73 {
69 74 struct statement *stmt;
70 75
71 76 /*
72 77 * we can't use __cur_stmt because that isn't set for
73 78 * iterator_pre_statement. Kind of a mess.
74 79 *
75 80 */
76 81
77 82 stmt = last_ptr_list((struct ptr_list *)big_statement_stack);
78 83
79 84 if (!stmt || !stmt->parent)
80 85 return 0;
81 86 if (stmt->parent->type != STMT_ITERATOR)
82 87 return 0;
83 88 if (stmt->parent->iterator_pre_statement != stmt)
84 89 return 0;
85 90 return 1;
86 91 }
87 92
88 93 static void match_assign(struct expression *expr)
89 94 {
90 95 struct range_list *rl;
91 96 struct symbol *type;
92 97 sval_t sval;
93 98
94 99 if (expr->op != '=')
95 100 return;
96 101 if (is_fake_call(expr->right))
97 102 return;
98 103 if (in_iterator_pre_statement())
99 104 return;
100 105
101 106 get_real_absolute_rl(expr->right, &rl);
102 107
103 108 type = get_type(expr->left);
104 109 if (!type)
105 110 return;
106 111 if (type->type != SYM_PTR && type->type != SYM_BASETYPE &&
107 112 type->type != SYM_ENUM)
108 113 return;
109 114
110 115 rl = cast_rl(type, rl);
111 116 if (is_whole_rl(rl) && !get_state_expr(my_id, expr->left))
112 117 return;
113 118 /* These are handled by smatch_extra.c */
114 119 if (rl_to_sval(rl, &sval) && !get_state_expr(my_id, expr->left))
115 120 return;
116 121
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117 122 set_state_expr(my_id, expr->left, alloc_estate_rl(clone_rl(rl)));
118 123 }
119 124
120 125 struct smatch_state *get_real_absolute_state(struct expression *expr)
121 126 {
122 127 return get_state_expr(my_id, expr);
123 128 }
124 129
125 130 struct smatch_state *get_real_absolute_state_var_sym(const char *name, struct symbol *sym)
126 131 {
127 - return get_state(my_id, name, sym);
132 + return __get_state(my_id, name, sym);
128 133 }
129 134
130 135 void register_real_absolute(int id)
131 136 {
132 137 my_id = id;
133 138
134 139 set_dynamic_states(my_id);
135 140 add_pre_merge_hook(my_id, &pre_merge_hook);
136 141 add_unmatched_state_hook(my_id, &empty_state);
137 142 add_merge_hook(my_id, &merge_estates);
138 - add_modification_hook(my_id, &reset);
143 + add_extra_mod_hook(&extra_mod_hook);
139 144
140 145 add_hook(&match_assign, ASSIGNMENT_HOOK);
141 146 }
142 147
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