src/symlist.h

   1 /* Lists of symbols for Bison
   2
   3    Copyright (C) 2002, 2005-2007, 2009-2015 Free Software Foundation,
   4    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 #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 to store the rules.  */
  30 typedef struct symbol_list
  31 {
  32   /**
  33    * Whether this node contains a symbol, a semantic type, a \c <*>, or a
  34    * \c <>.
  35    */
  36   enum {
  37     SYMLIST_SYMBOL,
  38     SYMLIST_TYPE
  39   } content_type;
  40   union {
  41     /**
  42      * The symbol or \c NULL iff
  43      * <tt>symbol_list::content_type = SYMLIST_SYMBOL</tt>.
  44      */
  45     symbol *sym;
  46     /**
  47      * The semantic type iff <tt>symbol_list::content_type = SYMLIST_TYPE</tt>.
  48      */
  49     semantic_type *sem_type;
  50   } content;
  51   location location;
  52
  53   /* Named reference. */
  54   named_ref *named_ref;
  55
  56   /* Proper location of the symbol, not all the rule */
  57   location sym_loc;
  58
  59   /* If this symbol is the generated lhs for a midrule but this is the rule in
  60      whose rhs it appears, MIDRULE = a pointer to that midrule.  */
  61   struct symbol_list *midrule;
  62
  63   /* If this symbol is the generated lhs for a midrule and this is that
  64      midrule, MIDRULE_PARENT_RULE = a pointer to the rule in whose rhs it
  65      appears, and MIDRULE_PARENT_RHS_INDEX = its rhs index (1-origin) in the
  66      parent rule.  */
  67   struct symbol_list *midrule_parent_rule;
  68   int midrule_parent_rhs_index;
  69
  70   /* ---------------------------------------------- */
  71   /* Apply to the rule (attached to the LHS only).  */
  72   /* ---------------------------------------------- */
  73
  74   /* Precedence/associativity.  */
  75   symbol *ruleprec;
  76
  77   /* The action is attached to the LHS of a rule, but action properties for
  78    * each RHS are also stored here.  */
  79   code_props action_props;
  80
  81   /* The location of the first %empty for this rule, or \a
  82      empty_location.  */
  83   location percent_empty_loc;
  84
  85   int dprec;
  86   location dprec_location;
  87   int merger;
  88   location merger_declaration_location;
  89
  90   /* The list.  */
  91   struct symbol_list *next;
  92 } symbol_list;
  93
  94
  95 /** Create a list containing \c sym at \c loc.  */
  96 symbol_list *symbol_list_sym_new (symbol *sym, location loc);
  97
  98 /** Create a list containing \c type_name at \c loc.  */
  99 symbol_list *symbol_list_type_new (uniqstr type_name, location loc);
 100
 101 /** Print this list.
 102
 103   \pre For every node \c n in the list, <tt>n->content_type =
 104   SYMLIST_SYMBOL</tt>.  */
 105 void symbol_list_syms_print (const symbol_list *l, FILE *f);
 106
 107 /** Prepend \c node to \c list.  */
 108 symbol_list *symbol_list_prepend (symbol_list *list, symbol_list *node);
 109
 110 /** Append \c node to \c list.  */
 111 symbol_list *symbol_list_append (symbol_list *list, symbol_list *node);
 112
 113 /** Free \c list, but not the items it contains.  */
 114 void symbol_list_free (symbol_list *list);
 115
 116 /** Return the length of \c l. */
 117 int symbol_list_length (symbol_list const *l);
 118
 119 /** Get item \c n in symbol list \c l.
 120  ** \pre  0 <= n
 121  ** \post res != NULL
 122  **/
 123 symbol_list *symbol_list_n_get (symbol_list *l, int n);
 124
 125 /* Get the data type (alternative in the union) of the value for
 126    symbol N in rule RULE.  */
 127 uniqstr symbol_list_n_type_name_get (symbol_list *l, int n);
 128
 129 /* Check whether the node is a border element of a rule. */
 130 bool symbol_list_null (symbol_list *node);
 131
 132 /** Set the \c \%destructor or \c \%printer for \c node as \c cprops.  */
 133 void symbol_list_code_props_set (symbol_list *node, code_props_type kind,
 134                                  code_props const *cprops);
 135
 136 #endif /* !SYMLIST_H_ */