1 /* Definitions for symtab.c and callers, part of Bison. 2 3 Copyright (C) 1984, 1989, 1992, 2000-2002, 2004-2007, 2009-2012 Free 4 Software 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 <http://www.gnu.org/licenses/>. */ 20 21 /** 22 * \file symtab.h 23 * \brief Manipulating ::symbol. 24 */ 25 26 #ifndef SYMTAB_H_ 27 # define SYMTAB_H_ 28 29 # include "assoc.h" 30 # include "location.h" 31 # include "scan-code.h" 32 # include "uniqstr.h" 33 34 /*----------. 35 | Symbols. | 36 `----------*/ 37 38 /** Symbol classes. */ 39 typedef enum 40 { 41 unknown_sym, /**< Undefined. */ 42 token_sym, /**< Terminal. */ 43 nterm_sym /**< Non-terminal. */ 44 } symbol_class; 45 46 47 /** Internal token numbers. */ 48 typedef int symbol_number; 49 #define SYMBOL_NUMBER_MAXIMUM INT_MAX 50 51 52 typedef struct symbol symbol; 53 54 /* When extending this structure, be sure to complete 55 symbol_check_alias_consistency. */ 56 struct symbol 57 { 58 /** The key, name of the symbol. */ 59 uniqstr tag; 60 /** The location of its first occurrence. */ 61 location location; 62 63 /** Its \c \%type. 64 65 Beware that this is the type_name as was entered by the user, 66 including silly things such as "]" if she entered "%token <]> t". 67 Therefore, when outputting type_name to M4, be sure to escape it 68 into "@}". See quoted_output for instance. */ 69 uniqstr type_name; 70 71 /** Its \c \%type's location. */ 72 location type_location; 73 74 /** Any \c \%destructor declared specifically for this symbol. 75 76 Access this field only through <tt>symbol</tt>'s interface 77 functions. For example, if <tt>symbol::destructor = NULL</tt>, a 78 default \c \%destructor or a per-type \c \%destructor might be 79 appropriate, and \c symbol_destructor_get will compute the 80 correct one. */ 81 code_props destructor; 82 83 /** Any \c \%printer declared specifically for this symbol. 84 85 Access this field only through <tt>symbol</tt>'s interface functions. 86 \sa symbol::destructor */ 87 code_props printer; 88 89 symbol_number number; 90 location prec_location; 91 int prec; 92 assoc assoc; 93 int user_token_number; 94 95 /* Points to the other in the symbol-string pair for an alias. 96 Special value USER_NUMBER_HAS_STRING_ALIAS in the symbol half of the 97 symbol-string pair for an alias. */ 98 symbol *alias; 99 symbol_class class; 100 bool declared; 101 }; 102 103 /** Undefined user number. */ 104 #define USER_NUMBER_UNDEFINED -1 105 106 /* `symbol->user_token_number == USER_NUMBER_HAS_STRING_ALIAS' means 107 this symbol has a literal string alias. For instance, `%token foo 108 "foo"' has `"foo"' numbered regularly, and `foo' numbered as 109 USER_NUMBER_HAS_STRING_ALIAS. */ 110 #define USER_NUMBER_HAS_STRING_ALIAS -9991 111 112 /* Undefined internal token number. */ 113 #define NUMBER_UNDEFINED (-1) 114 115 /** Print a symbol (for debugging). */ 116 void symbol_print (symbol *s, FILE *f); 117 118 /** Fetch (or create) the symbol associated to KEY. */ 119 symbol *symbol_from_uniqstr (const uniqstr key, location loc); 120 121 /** Fetch (or create) the symbol associated to KEY. */ 122 symbol *symbol_get (const char *key, location loc); 123 124 /** Generate a dummy nonterminal. 125 126 Its name cannot conflict with the user's names. */ 127 symbol *dummy_symbol_get (location loc); 128 129 /** Is this a dummy nonterminal? */ 130 bool symbol_is_dummy (const symbol *sym); 131 132 /** 133 * Make \c str the literal string alias of \c sym. Copy token number, 134 * symbol number, and type from \c sym to \c str. 135 */ 136 void symbol_make_alias (symbol *sym, symbol *str, location loc); 137 138 /** Set the \c type_name associated with \c sym. 139 140 Do nothing if passed 0 as \c type_name. */ 141 void symbol_type_set (symbol *sym, uniqstr type_name, location loc); 142 143 /** Set the \c destructor associated with \c sym. */ 144 void symbol_destructor_set (symbol *sym, code_props const *destructor); 145 146 /** Get the computed \c \%destructor for \c sym, which was initialized with 147 \c code_props_none_init if there's no \c \%destructor. */ 148 code_props const *symbol_destructor_get (symbol const *sym); 149 150 /** Set the \c printer associated with \c sym. */ 151 void symbol_printer_set (symbol *sym, code_props const *printer); 152 153 /** Get the computed \c \%printer for \c sym, which was initialized with 154 \c code_props_none_init if there's no \c \%printer. */ 155 code_props const *symbol_printer_get (symbol const *sym); 156 157 /* Set the \c precedence associated with \c sym. 158 159 Ensure that \a symbol is a terminal. 160 Do nothing if invoked with \c undef_assoc as \c assoc. */ 161 void symbol_precedence_set (symbol *sym, int prec, assoc a, location loc); 162 163 /** Set the \c class associated with \c sym. */ 164 void symbol_class_set (symbol *sym, symbol_class class, location loc, 165 bool declaring); 166 167 /** Set the \c user_token_number associated with \c sym. */ 168 void symbol_user_token_number_set (symbol *sym, int user_number, location loc); 169 170 171 /** The error token. */ 172 extern symbol *errtoken; 173 /** The token for unknown tokens. */ 174 extern symbol *undeftoken; 175 /** The end of input token. */ 176 extern symbol *endtoken; 177 /** The genuine start symbol. 178 179 $accept: start-symbol $end */ 180 extern symbol *accept; 181 182 /** The user start symbol. */ 183 extern symbol *startsymbol; 184 /** The location of the \c \%start declaration. */ 185 extern location startsymbol_location; 186 187 188 /*-----------------. 189 | Semantic types. | 190 `-----------------*/ 191 192 /** A semantic type and its associated \c \%destructor and \c \%printer. 193 194 Access the fields of this struct only through the interface functions in 195 this file. \sa symbol::destructor */ 196 typedef struct { 197 /** The key, name of the semantic type. */ 198 uniqstr tag; 199 200 /** Any \c %destructor declared for this semantic type. */ 201 code_props destructor; 202 /** Any \c %printer declared for this semantic type. */ 203 code_props printer; 204 } semantic_type; 205 206 /** Fetch (or create) the semantic type associated to KEY. */ 207 semantic_type *semantic_type_from_uniqstr (const uniqstr key); 208 209 /** Fetch (or create) the semantic type associated to KEY. */ 210 semantic_type *semantic_type_get (const char *key); 211 212 /** Set the \c destructor associated with \c type. */ 213 void semantic_type_destructor_set (semantic_type *type, 214 code_props const *destructor); 215 216 /** Set the \c printer associated with \c type. */ 217 void semantic_type_printer_set (semantic_type *type, 218 code_props const *printer); 219 220 /*----------------------------------. 221 | Symbol and semantic type tables. | 222 `----------------------------------*/ 223 224 /** Create the symbol and semantic type tables. */ 225 void symbols_new (void); 226 227 /** Free all the memory allocated for symbols and semantic types. */ 228 void symbols_free (void); 229 230 /** Check that all the symbols are defined. 231 232 Report any undefined symbols and consider them nonterminals. */ 233 void symbols_check_defined (void); 234 235 /** Sanity checks and #token_translations construction. 236 237 Perform various sanity checks, assign symbol numbers, and set up 238 #token_translations. */ 239 void symbols_pack (void); 240 241 242 /*---------------------------------------. 243 | Default %destructor's and %printer's. | 244 `---------------------------------------*/ 245 246 /** Set the default \c \%destructor for tagged values. */ 247 void default_tagged_destructor_set (code_props const *destructor); 248 /** Set the default \c \%destructor for tagless values. */ 249 void default_tagless_destructor_set (code_props const *destructor); 250 251 /** Set the default \c \%printer for tagged values. */ 252 void default_tagged_printer_set (code_props const *printer); 253 /** Set the default \c \%printer for tagless values. */ 254 void default_tagless_printer_set (code_props const *printer); 255 256 #endif /* !SYMTAB_H_ */ 257