1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
|
struct token *TYPE_NAMES[1024];
size_t N_TYPE_NAMES;
void alert_parse(struct state *state) {
if (PRODUCTION_ID_TO_SYMBOL[state->production_id] == SYMBOL_TYPEDEF) {
for (struct token *t = find_token(state, 2); t->symbol != DONE_SYMBOL; t++) {
if (t->symbol == SYMBOL_IDENT) {
TYPE_NAMES[N_TYPE_NAMES++] = t;
break;
}
}
}
}
int is_typename(struct token *token) {
if (!strcmp("int", token->string)) return 1;
for (size_t i = 0; i < N_TYPE_NAMES; i++)
if (!strcmp(TYPE_NAMES[i]->string, token->string))
return 1;
return 0;
}
int disambiguator(struct state *old, struct state *new) {
// printf("Old tree:\n");
// print_parse_tree(old, 4);
// printf("New tree:\n");
// print_parse_tree(new, 4);
if (old->production_id == PRODUCTION_DECL_STMT)
if (!is_typename(find_token(old->reasons[0], 0)))
return 1;
if (new->production_id == PRODUCTION_DECL_STMT)
if (!is_typename(find_token(new->reasons[0], 0)))
return 0;
// Prefer the earlier parsings in the grammar when two entirely different
// productions are taken.
if (old->production_id != new->production_id)
return old->production_id < new->production_id
? 0 : 1;
// If they're the same production ...
prod_id_t prod = old->production_id;
if (PRODUCTION_ID_TO_SYMBOL[prod] == SYMBOL_EXPR) {
if (PRODUCTION_ID_TO_PRODUCTION[prod][1] == SYMBOL_OP) {
struct token *old_tok = find_token(old, 1),
*new_tok = find_token(new, 1);
char *old_s = old_tok->string, *new_s = new_tok->string;
const char *precedence[] = {".", "->", "*", "/", "%", "+", "-",
"<<", ">>", "<", "<=", ">", ">=", "==", "!=", "&", "|", "&&",
"||", "=", "+=", "-=", "*=", "/=", "%=", "<<=", ">>=", "&=",
"^=", "|=", ",", 0};
if (strcmp(old_s, new_s)) {
for (const char **p = precedence; *p; p++) {
if (!strcmp(old_s, *p)) {
return 1;
} else if (!strcmp(new_s, *p)) {
return 0;
}
}
// BAD!
return 2;
} else {
// Associate RIGHT
if (old_tok < new_tok) return 1;
else if (old_tok > new_tok) return 0;
}
}
}
fprintf(stderr, "TOTALLY UNKNOWN!\n");
return 2;
}
|
