1 /* Lists of symbols for Bison
2
3 Copyright (C) 2002, 2005-2007, 2009-2015, 2018-2021 Free Software
4 Foundation, Inc.
5
6 This file is part of Bison, the GNU Compiler Compiler.
7
8 This program is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation, either version 3 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <https://www.gnu.org/licenses/>. */
20
21 #ifndef SYMLIST_H_
22 # define SYMLIST_H_
23
24 # include "location.h"
25 # include "scan-code.h"
26 # include "symtab.h"
27 # include "named-ref.h"
28
29 /* A list of symbols, used during the parsing for many different
30 purposes: rules, symbol declarations or properties (such as
31 %destructor, etc.)... */
32 typedef struct symbol_list
33 {
34 /**
35 * Whether this node contains a symbol, a semantic type, a \c <*>, or a
36 * \c <>.
37 */
38 enum {
39 SYMLIST_SYMBOL,
40 SYMLIST_TYPE
41 } content_type;
42 union {
43 /**
44 * The symbol or \c NULL iff
45 * <tt>symbol_list::content_type = SYMLIST_SYMBOL</tt>.
46 */
47 symbol *sym;
48 /**
49 * The semantic type iff <tt>symbol_list::content_type = SYMLIST_TYPE</tt>.
50 */
51 semantic_type *sem_type;
52 } content;
53
54 /* Named reference. */
55 named_ref *named_ref;
56
57 /* Proper location of the symbol, not all the rule */
58 location sym_loc;
59
60 /* If this symbol is the generated lhs for a midrule but this is the rule in
61 whose rhs it appears, MIDRULE = a pointer to that midrule. */
62 struct symbol_list *midrule;
63
64 /* If this symbol is the generated lhs for a midrule and this is that
65 midrule, MIDRULE_PARENT_RULE = a pointer to the rule in whose rhs it
66 appears, and MIDRULE_PARENT_RHS_INDEX = its rhs index (1-origin) in the
67 parent rule. */
68 struct symbol_list *midrule_parent_rule;
69 int midrule_parent_rhs_index;
70
71 /*--------------------------------------------------------------.
72 | Used for rules only (attached to the "LHS", one per rule even |
73 | when several RHSs are bound to a single lhs via "|"). |
74 `--------------------------------------------------------------*/
75
76 /* Location of the RHS. */
77 location rhs_loc;
78
79 /* Precedence/associativity. */
80 symbol *ruleprec;
81
82 /* The action is attached to the LHS of a rule, but action properties for
83 * each RHS are also stored here. */
84 code_props action_props;
85
86 /* The location of the first %empty for this rule, or \a
87 empty_loc. */
88 location percent_empty_loc;
89
90 int dprec;
91 location dprec_loc;
92 int merger;
93 location merger_declaration_loc;
94
95 /* Counts of the number of expected conflicts for this rule, or -1 if none
96 given. */
97 int expected_sr_conflicts;
98 int expected_rr_conflicts;
99
100 /* The list. */
101 struct symbol_list *next;
102 } symbol_list;
103
104
105 /** Create a list containing \c sym at \c loc. */
106 symbol_list *symbol_list_sym_new (symbol *sym, location loc);
107
108 /** Create a list containing \c type_name at \c loc. */
109 symbol_list *symbol_list_type_new (uniqstr type_name, location loc);
110
111 /** Assign the type \c type_name to all the members of \c syms.
112 ** \returns \c syms */
113 symbol_list *symbol_list_type_set (symbol_list *syms, uniqstr type_name);
114
115 /** Find a symbol with the same content as \c sym within \c syms. */
116 symbol_list *symbol_list_find_symbol (symbol_list *syms, const symbol *sym);
117
118 /** Print this list.
119
120 \pre For every node \c n in the list, <tt>n->content_type =
121 SYMLIST_SYMBOL</tt>. */
122 void symbol_list_syms_print (const symbol_list *l, FILE *f);
123
124 /** Prepend \c node to \c list. */
125 symbol_list *symbol_list_prepend (symbol_list *list, symbol_list *node);
126
127 /** The last node of this list. */
128 symbol_list *symbol_list_last (symbol_list *list);
129
130 /** Append \c node to \c list. */
131 symbol_list *symbol_list_append (symbol_list *list, symbol_list *node);
132
133 /** Free \c list, but not the items it contains. */
134 void symbol_list_free (symbol_list *list);
135
136 /** Return the length of \c l. */
137 int symbol_list_length (symbol_list const *l);
138
139 /** Get item \c n in symbol list \c l.
140 ** \pre 0 <= n
141 ** \post res != NULL
142 **/
143 symbol_list *symbol_list_n_get (symbol_list *l, int n);
144
145 /** Get the data type (alternative in the union) of the value for
146 symbol N in rule RULE. */
147 uniqstr symbol_list_n_type_name_get (symbol_list *l, int n);
148
149 /** Check whether the node is a border element of a rule. */
150 bool symbol_list_null (symbol_list *node);
151
152 /** Set the \c \%destructor or \c \%printer for \c node as \c cprops. */
153 void symbol_list_code_props_set (symbol_list *node, code_props_type kind,
154 code_props const *cprops);
155
156 #endif /* !SYMLIST_H_ */