1 #include "smatch.h"
2 #include "smatch_extra.h"
3
4 DECLARE_ALLOCATOR(sname);
5 __ALLOCATOR(struct expression, "temporary expr", tmp_expression);
6
7 static struct position get_cur_pos(void)
8 {
9 static struct position pos;
10 static struct position none;
11 struct expression *expr;
12 struct statement *stmt;
13
14 expr = last_ptr_list((struct ptr_list *)big_expression_stack);
15 stmt = last_ptr_list((struct ptr_list *)big_statement_stack);
16 if (expr)
17 pos = expr->pos;
18 else if (stmt)
19 pos = stmt->pos;
20 else
21 pos = none;
22 return pos;
23 }
24
25 struct expression *alloc_tmp_expression(struct position pos, int type)
26 {
27 struct expression *expr;
28
29 expr = __alloc_tmp_expression(0);
30 expr->smatch_flags |= Fake;
31 expr->type = type;
32 expr->pos = pos;
33 return expr;
34 }
35
36 void free_tmp_expressions(void)
37 {
38 clear_tmp_expression_alloc();
39 }
40
41 struct expression *zero_expr(void)
42 {
43 struct expression *zero;
44
45 zero = alloc_tmp_expression(get_cur_pos(), EXPR_VALUE);
46 zero->value = 0;
47 zero->ctype = &int_ctype;
48 return zero;
49 }
50
51 struct expression *value_expr(long long val)
52 {
53 struct expression *expr;
54
55 if (!val)
56 return zero_expr();
57
58 expr = alloc_tmp_expression(get_cur_pos(), EXPR_VALUE);
59 expr->value = val;
60 expr->ctype = &llong_ctype;
61 return expr;
62 }
63
64 struct expression *member_expression(struct expression *deref, int op, struct ident *member)
65 {
66 struct expression *expr;
67
68 expr = alloc_tmp_expression(deref->pos, EXPR_DEREF);
69 expr->op = op;
70 expr->deref = deref;
71 expr->member = member;
72 expr->member_offset = -1;
73 return expr;
74 }
75
76 struct expression *preop_expression(struct expression *expr, int op)
77 {
78 struct expression *preop;
79
80 preop = alloc_tmp_expression(expr->pos, EXPR_PREOP);
81 preop->unop = expr;
82 preop->op = op;
83 return preop;
84 }
85
86 struct expression *deref_expression(struct expression *expr)
87 {
88 return preop_expression(expr, '*');
89 }
90
91 struct expression *assign_expression(struct expression *left, int op, struct expression *right)
92 {
93 struct expression *expr;
94
95 if (!right)
96 return NULL;
97
98 /* FIXME: make this a tmp expression. */
99 expr = alloc_expression(right->pos, EXPR_ASSIGNMENT);
100 expr->op = op;
101 expr->left = left;
102 expr->right = right;
103 return expr;
104 }
105
106 struct expression *binop_expression(struct expression *left, int op, struct expression *right)
107 {
108 struct expression *expr;
109
110 expr = alloc_tmp_expression(right->pos, EXPR_BINOP);
111 expr->op = op;
112 expr->left = left;
113 expr->right = right;
114 return expr;
115 }
116
117 struct expression *array_element_expression(struct expression *array, struct expression *offset)
118 {
119 struct expression *expr;
120
121 expr = binop_expression(array, '+', offset);
122 return deref_expression(expr);
123 }
124
125 struct expression *symbol_expression(struct symbol *sym)
126 {
127 struct expression *expr;
128
129 expr = alloc_tmp_expression(sym->pos, EXPR_SYMBOL);
130 expr->symbol = sym;
131 expr->symbol_name = sym->ident;
132 return expr;
133 }
134
135 struct expression *compare_expression(struct expression *left, int op, struct expression *right)
136 {
137 struct expression *expr;
138
139 expr = alloc_tmp_expression(get_cur_pos(), EXPR_COMPARE);
140 expr->op = op;
141 expr->left = left;
142 expr->right = right;
143 return expr;
144 }
145
146 struct expression *string_expression(char *str)
147 {
148 struct expression *ret;
149 struct string *string;
150 int len;
151
152 len = strlen(str) + 1;
153 string = (void *)__alloc_sname(4 + len);
154 string->length = len;
155 string->immutable = 0;
156 memcpy(string->data, str, len);
157
158 ret = alloc_tmp_expression(get_cur_pos(), EXPR_STRING);
159 ret->wide = 0;
160 ret->string = string;
161
162 return ret;
163 }
164
165 struct expression *gen_expression_from_key(struct expression *arg, const char *key)
166 {
167 struct expression *ret;
168 struct token *token, *end;
169 const char *p = key;
170 char buf[4095];
171 char *alloc;
172 size_t len;
173
174 /* The idea is that we can parse either $0->foo or $->foo */
175 if (key[0] != '$')
176 return NULL;
177 p++;
178 while (*p >= '0' && *p <= '9')
179 p++;
180 len = snprintf(buf, sizeof(buf), "%s\n", p);
181 alloc = alloc_string(buf);
182
183 token = tokenize_buffer(alloc, len, &end);
184 if (!token)
185 return NULL;
186 if (token_type(token) != TOKEN_STREAMBEGIN)
187 return NULL;
188 token = token->next;
189
190 ret = arg;
191 while (token_type(token) == TOKEN_SPECIAL &&
192 token->special == SPECIAL_DEREFERENCE) {
193 token = token->next;
194 if (token_type(token) != TOKEN_IDENT)
195 return NULL;
196 ret = deref_expression(ret);
197 ret = member_expression(ret, '*', token->ident);
198 token = token->next;
199 }
200
201 if (token_type(token) != TOKEN_STREAMEND)
202 return NULL;
203
204 return ret;
205 }
206
207 void expr_set_parent_expr(struct expression *expr, struct expression *parent)
208 {
209 if (!expr)
210 return;
211 if (parent->smatch_flags & Fake)
212 return;
213
214 expr->parent = (unsigned long)parent | 0x1UL;
215 }
216
217 void expr_set_parent_stmt(struct expression *expr, struct statement *parent)
218 {
219 if (!expr)
220 return;
221 expr->parent = (unsigned long)parent;
222 }
223
224 struct expression *expr_get_parent_expr(struct expression *expr)
225 {
226 if (!expr)
227 return NULL;
228 if (!(expr->parent & 0x1UL))
229 return NULL;
230 return (struct expression *)(expr->parent & ~0x1UL);
231 }
232
233 struct statement *expr_get_parent_stmt(struct expression *expr)
234 {
235 if (!expr)
236 return NULL;
237 if (expr->parent & 0x1UL)
238 return NULL;
239 return (struct statement *)expr->parent;
240 }
241