1 | /* Declarations for the parser for C and Objective-C. |
2 | Copyright (C) 1987-2023 Free Software Foundation, Inc. |
3 | |
4 | Parser actions based on the old Bison parser; structure somewhat |
5 | influenced by and fragments based on the C++ parser. |
6 | |
7 | This file is part of GCC. |
8 | |
9 | GCC is free software; you can redistribute it and/or modify it under |
10 | the terms of the GNU General Public License as published by the Free |
11 | Software Foundation; either version 3, or (at your option) any later |
12 | version. |
13 | |
14 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
15 | WARRANTY; without even the implied warranty of MERCHANTABILITY or |
16 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
17 | for more details. |
18 | |
19 | You should have received a copy of the GNU General Public License |
20 | along with GCC; see the file COPYING3. If not see |
21 | <http://www.gnu.org/licenses/>. */ |
22 | |
23 | #ifndef GCC_C_PARSER_H |
24 | #define GCC_C_PARSER_H |
25 | |
26 | /* The C lexer intermediates between the lexer in cpplib and c-lex.cc |
27 | and the C parser. Unlike the C++ lexer, the parser structure |
28 | stores the lexer information instead of using a separate structure. |
29 | Identifiers are separated into ordinary identifiers, type names, |
30 | keywords and some other Objective-C types of identifiers, and some |
31 | look-ahead is maintained. |
32 | |
33 | ??? It might be a good idea to lex the whole file up front (as for |
34 | C++). It would then be possible to share more of the C and C++ |
35 | lexer code, if desired. */ |
36 | |
37 | /* More information about the type of a CPP_NAME token. */ |
38 | enum c_id_kind { |
39 | /* An ordinary identifier. */ |
40 | C_ID_ID, |
41 | /* An identifier declared as a typedef name. */ |
42 | C_ID_TYPENAME, |
43 | /* An identifier declared as an Objective-C class name. */ |
44 | C_ID_CLASSNAME, |
45 | /* An address space identifier. */ |
46 | C_ID_ADDRSPACE, |
47 | /* Not an identifier. */ |
48 | C_ID_NONE |
49 | }; |
50 | |
51 | /* A single C token after string literal concatenation and conversion |
52 | of preprocessing tokens to tokens. */ |
53 | struct GTY (()) c_token { |
54 | /* The kind of token. */ |
55 | ENUM_BITFIELD (cpp_ttype) type : 8; |
56 | /* If this token is a CPP_NAME, this value indicates whether also |
57 | declared as some kind of type. Otherwise, it is C_ID_NONE. */ |
58 | ENUM_BITFIELD (c_id_kind) id_kind : 8; |
59 | /* If this token is a keyword, this value indicates which keyword. |
60 | Otherwise, this value is RID_MAX. */ |
61 | ENUM_BITFIELD (rid) keyword : 8; |
62 | /* If this token is a CPP_PRAGMA, this indicates the pragma that |
63 | was seen. Otherwise it is PRAGMA_NONE. */ |
64 | ENUM_BITFIELD (pragma_kind) pragma_kind : 8; |
65 | /* The location at which this token was found. */ |
66 | location_t location; |
67 | /* The value associated with this token, if any. */ |
68 | tree value; |
69 | /* Token flags. */ |
70 | unsigned char flags; |
71 | |
72 | source_range get_range () const |
73 | { |
74 | return get_range_from_loc (set: line_table, loc: location); |
75 | } |
76 | |
77 | location_t get_finish () const |
78 | { |
79 | return get_range ().m_finish; |
80 | } |
81 | }; |
82 | |
83 | /* This should have the same layout as c_tree_token_vec |
84 | in c-decl.cc, but for GTY reasons with ObjC can't be |
85 | GTY itself. */ |
86 | struct c_tree_token_vec_struct { |
87 | struct tree_base base; |
88 | vec<c_token, va_gc> *tokens; |
89 | }; |
90 | |
91 | #define C_TOKEN_VEC_TOKENS(NODE) \ |
92 | (((struct c_tree_token_vec_struct *) TREE_CHECK (NODE, C_TOKEN_VEC))->tokens) |
93 | |
94 | /* The parser. */ |
95 | struct c_parser; |
96 | |
97 | /* Possibly kinds of declarator to parse. */ |
98 | enum c_dtr_syn { |
99 | /* A normal declarator with an identifier. */ |
100 | C_DTR_NORMAL, |
101 | /* An abstract declarator (maybe empty). */ |
102 | C_DTR_ABSTRACT, |
103 | /* A parameter declarator: may be either, but after a type name does |
104 | not redeclare a typedef name as an identifier if it can |
105 | alternatively be interpreted as a typedef name; see DR#009, |
106 | applied in C90 TC1, omitted from C99 and reapplied in C99 TC2 |
107 | following DR#249. For example, given a typedef T, "int T" and |
108 | "int *T" are valid parameter declarations redeclaring T, while |
109 | "int (T)" and "int * (T)" and "int (T[])" and "int (T (int))" are |
110 | abstract declarators rather than involving redundant parentheses; |
111 | the same applies with attributes inside the parentheses before |
112 | "T". */ |
113 | C_DTR_PARM |
114 | }; |
115 | |
116 | /* The binary operation precedence levels, where 0 is a dummy lowest level |
117 | used for the bottom of the stack. */ |
118 | enum c_parser_prec { |
119 | PREC_NONE, |
120 | PREC_LOGOR, |
121 | PREC_LOGAND, |
122 | PREC_BITOR, |
123 | PREC_BITXOR, |
124 | PREC_BITAND, |
125 | PREC_EQ, |
126 | PREC_REL, |
127 | PREC_SHIFT, |
128 | PREC_ADD, |
129 | PREC_MULT, |
130 | NUM_PRECS |
131 | }; |
132 | |
133 | enum c_lookahead_kind { |
134 | /* Always treat unknown identifiers as typenames. */ |
135 | cla_prefer_type, |
136 | |
137 | /* Could be parsing a nonabstract declarator. Only treat an identifier |
138 | as a typename if followed by another identifier or a star. */ |
139 | cla_nonabstract_decl, |
140 | |
141 | /* Never treat identifiers as typenames. */ |
142 | cla_prefer_id |
143 | }; |
144 | |
145 | |
146 | extern c_token * c_parser_peek_token (c_parser *parser); |
147 | extern c_token * c_parser_peek_2nd_token (c_parser *parser); |
148 | extern c_token * c_parser_peek_nth_token (c_parser *parser, unsigned int n); |
149 | extern bool c_parser_require (c_parser *parser, enum cpp_ttype type, |
150 | const char *msgid, |
151 | location_t matching_location = UNKNOWN_LOCATION, |
152 | bool type_is_unique=true); |
153 | extern bool c_parser_error (c_parser *parser, const char *gmsgid); |
154 | extern void c_parser_consume_token (c_parser *parser); |
155 | extern void c_parser_skip_until_found (c_parser *parser, enum cpp_ttype type, |
156 | const char *msgid, |
157 | location_t = UNKNOWN_LOCATION); |
158 | extern bool c_parser_next_token_starts_declspecs (c_parser *parser); |
159 | bool c_parser_next_tokens_start_declaration (c_parser *parser); |
160 | bool c_token_starts_typename (c_token *token); |
161 | |
162 | /* Abstraction to avoid defining c_parser here which messes up gengtype |
163 | output wrt ObjC due to vec<c_token> routines being put in gtype-c.h |
164 | but not gtype-objc.h. */ |
165 | extern c_token * c_parser_tokens_buf (c_parser *parser, unsigned n); |
166 | extern bool c_parser_error (c_parser *parser); |
167 | extern void c_parser_set_error (c_parser *parser, bool); |
168 | |
169 | /* A bit of a hack to have this here. It would be better in a c-decl.h. */ |
170 | extern bool old_style_parameter_scope (void); |
171 | |
172 | /* Return true if the next token from PARSER has the indicated |
173 | TYPE. */ |
174 | |
175 | inline bool |
176 | c_parser_next_token_is (c_parser *parser, enum cpp_ttype type) |
177 | { |
178 | return c_parser_peek_token (parser)->type == type; |
179 | } |
180 | |
181 | /* Return true if the next token from PARSER does not have the |
182 | indicated TYPE. */ |
183 | |
184 | inline bool |
185 | c_parser_next_token_is_not (c_parser *parser, enum cpp_ttype type) |
186 | { |
187 | return !c_parser_next_token_is (parser, type); |
188 | } |
189 | |
190 | /* Return true if the next token from PARSER is the indicated |
191 | KEYWORD. */ |
192 | |
193 | inline bool |
194 | c_parser_next_token_is_keyword (c_parser *parser, enum rid keyword) |
195 | { |
196 | return c_parser_peek_token (parser)->keyword == keyword; |
197 | } |
198 | |
199 | struct c_expr c_parser_string_literal (c_parser *, bool, bool); |
200 | extern struct c_declarator * |
201 | c_parser_declarator (c_parser *parser, bool type_seen_p, c_dtr_syn kind, |
202 | bool *seen_id); |
203 | extern void c_parser_declspecs (c_parser *, struct c_declspecs *, bool, bool, |
204 | bool, bool, bool, bool, bool, |
205 | enum c_lookahead_kind); |
206 | extern struct c_type_name *c_parser_type_name (c_parser *, bool = false); |
207 | extern bool c_maybe_parse_omp_decl (tree, tree); |
208 | |
209 | #endif |
210 | |