X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/1462fcee1ed295b24f47758b370068aa6304bb41..fd003416d59cae9645d164b12495eb186efee848:/src/symtab.h

diff --git a/src/symtab.h b/src/symtab.h
index 9fd92a16..f585fd7b 100644
--- a/src/symtab.h
+++ b/src/symtab.h
@@ -1,7 +1,7 @@
 /* Definitions for symtab.c and callers, part of Bison.
 
-   Copyright (C) 1984, 1989, 1992, 2000-2002, 2004-2007, 2009-2010 Free
-   Software Foundation, Inc.
+   Copyright (C) 1984, 1989, 1992, 2000-2002, 2004-2013 Free Software
+   Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
@@ -39,18 +39,49 @@
 typedef enum
 {
   unknown_sym,          /**< Undefined.  */
-  token_sym,		/**< Terminal. */
-  nterm_sym		/**< Non-terminal. */
+  token_sym,            /**< Terminal. */
+  nterm_sym             /**< Non-terminal. */
 } symbol_class;
 
 
 /** Internal token numbers. */
 typedef int symbol_number;
-#define SYMBOL_NUMBER_MAXIMUM INT_MAX
+# define SYMBOL_NUMBER_MAXIMUM INT_MAX
 
 
 typedef struct symbol symbol;
 
+/* Declaration status of a symbol.
+
+   First, it is "undeclared".  Then, if "undeclared" and used in a
+   %printer/%destructor, it is "used".  If not "declared" but used in
+   a rule, it is "needed".  Finally, if declared (via a rule for
+   nonterminals, or %token), it is "declared".
+
+   When status are checked at the end, "declared" symbols are fine,
+   "used" symbols trigger warnings, otherwise it's an error.  */
+
+typedef enum
+  {
+    /** Used in the input file for an unknown reason (error).  */
+    undeclared,
+    /** Used by %destructor/%printer but not defined (warning).  */
+    used,
+    /** Used in the gramar (rules) but not defined (error).  */
+    needed,
+    /** Defined with %type or %token (good).  */
+    declared,
+  } status;
+
+typedef enum code_props_type code_props_type;
+enum code_props_type
+  {
+    destructor = 0,
+    printer = 1,
+  };
+
+enum { CODE_PROPS_SIZE = 2 };
+
 /* When extending this structure, be sure to complete
    symbol_check_alias_consistency.  */
 struct symbol
@@ -60,24 +91,25 @@ struct symbol
   /** The location of its first occurrence.  */
   location location;
 
-  /** Its \c \%type.  */
+  /** Its \c \%type.
+
+      Beware that this is the type_name as was entered by the user,
+      including silly things such as "]" if she entered "%token <]> t".
+      Therefore, when outputting type_name to M4, be sure to escape it
+      into "@}".  See quoted_output for instance.  */
   uniqstr type_name;
+
   /** Its \c \%type's location.  */
   location type_location;
 
-  /** Any \c \%destructor declared specifically for this symbol.
+  /** Any \c \%destructor (resp. \%printer) declared specificially for this
+      symbol.
 
-     Access this field only through <tt>symbol</tt>'s interface functions.  For
-     example, if <tt>symbol::destructor = NULL</tt>, a default \c \%destructor
-     or a per-type \c \%destructor might be appropriate, and
-     \c symbol_destructor_get will compute the correct one.  */
-  code_props destructor;
-
-  /** Any \c \%printer declared specifically for this symbol.
-
-     Access this field only through <tt>symbol</tt>'s interface functions.
-     \sa symbol::destructor  */
-  code_props printer;
+      Access this field only through <tt>symbol</tt>'s interface functions. For
+      example, if <tt>symbol::destructor = NULL</tt> (resp. <tt>symbol::printer
+      = NULL</tt>), a default \c \%destructor (resp. \%printer) or a per-type
+      \c symbol_destructor_printer_get will compute the correct one. */
+  code_props props[CODE_PROPS_SIZE];
 
   symbol_number number;
   location prec_location;
@@ -90,23 +122,20 @@ struct symbol
      symbol-string pair for an alias.  */
   symbol *alias;
   symbol_class class;
-  bool declared;
+  status status;
 };
 
 /** Undefined user number.  */
-#define USER_NUMBER_UNDEFINED -1
+# define USER_NUMBER_UNDEFINED -1
 
 /* `symbol->user_token_number == USER_NUMBER_HAS_STRING_ALIAS' means
    this symbol has a literal string alias.  For instance, `%token foo
    "foo"' has `"foo"' numbered regularly, and `foo' numbered as
    USER_NUMBER_HAS_STRING_ALIAS.  */
-#define USER_NUMBER_HAS_STRING_ALIAS -9991
+# define USER_NUMBER_HAS_STRING_ALIAS -9991
 
 /* Undefined internal token number.  */
-#define NUMBER_UNDEFINED (-1)
-
-/** Print a symbol (for debugging). */
-void symbol_print (symbol *s, FILE *f);
+# define NUMBER_UNDEFINED (-1)
 
 /** Fetch (or create) the symbol associated to KEY.  */
 symbol *symbol_from_uniqstr (const uniqstr key, location loc);
@@ -119,9 +148,26 @@ symbol *symbol_get (const char *key, location loc);
    Its name cannot conflict with the user's names.  */
 symbol *dummy_symbol_get (location loc);
 
+
+/*--------------------.
+| Methods on symbol.  |
+`--------------------*/
+
+/** Print a symbol (for debugging). */
+void symbol_print (symbol const *s, FILE *f);
+
 /** Is this a dummy nonterminal?  */
 bool symbol_is_dummy (const symbol *sym);
 
+/** The name of the code_props type: "\%destructor" or "\%printer".  */
+char const *code_props_type_string (code_props_type kind);
+
+/** The name of the symbol that can be used as an identifier.
+ ** Consider the alias if needed.
+ ** Return 0 if there is none (e.g., the symbol is only defined as
+ ** a string). */
+uniqstr symbol_id_get (symbol const *sym);
+
 /**
  * Make \c str the literal string alias of \c sym.  Copy token number,
  * symbol number, and type from \c sym to \c str.
@@ -133,34 +179,34 @@ void symbol_make_alias (symbol *sym, symbol *str, location loc);
     Do nothing if passed 0 as \c type_name.  */
 void symbol_type_set (symbol *sym, uniqstr type_name, location loc);
 
-/** Set the \c destructor associated with \c sym.  */
-void symbol_destructor_set (symbol *sym, code_props const *destructor);
+/** Set the \c \%destructor or \c \%printer associated with \c sym.  */
+void symbol_code_props_set (symbol *sym, code_props_type kind,
+                            code_props const *destructor);
 
-/** Get the computed \c \%destructor for \c sym, which was initialized with
-    \c code_props_none_init if there's no \c \%destructor.  */
-code_props const *symbol_destructor_get (symbol const *sym);
+/** Get the computed \c \%destructor or \c %printer for \c sym, which was
+    initialized with \c code_props_none_init if there's no \c \%destructor or
+    \c %printer.  */
+code_props *symbol_code_props_get (symbol *sym, code_props_type kind);
 
-/** Set the \c printer associated with \c sym.  */
-void symbol_printer_set (symbol *sym, code_props const *printer);
+/** Set the \c precedence associated with \c sym.
 
-/** Get the computed \c \%printer for \c sym, which was initialized with
-    \c code_props_none_init if there's no \c \%printer.  */
-code_props const *symbol_printer_get (symbol const *sym);
-
-/* Set the \c precedence associated with \c sym.
-
-   Ensure that \a symbol is a terminal.
-   Do nothing if invoked with \c undef_assoc as \c assoc.  */
+    Ensure that \a symbol is a terminal.
+    Do nothing if invoked with \c undef_assoc as \c assoc.  */
 void symbol_precedence_set (symbol *sym, int prec, assoc a, location loc);
 
 /** Set the \c class associated with \c sym.  */
 void symbol_class_set (symbol *sym, symbol_class class, location loc,
-		       bool declaring);
+                       bool declaring);
 
 /** Set the \c user_token_number associated with \c sym.  */
 void symbol_user_token_number_set (symbol *sym, int user_number, location loc);
 
 
+
+/*------------------.
+| Special symbols.  |
+`------------------*/
+
 /** The error token. */
 extern symbol *errtoken;
 /** The token for unknown tokens.  */
@@ -178,6 +224,59 @@ extern symbol *startsymbol;
 extern location startsymbol_location;
 
 
+
+/*-------------------.
+| Symbol Relations.  |
+`-------------------*/
+
+/* The symbol relations are represented by a directed graph. */
+
+/* The id of a node */
+typedef int graphid;
+
+typedef struct symgraphlink symgraphlink;
+
+struct symgraphlink
+{
+  /** The second \c symbol or group of a precedence relation.
+   * See \c symgraph. */
+  graphid id;
+
+  symgraphlink *next;
+};
+
+/* Symbol precedence graph, to store the used precedence relations between
+ * symbols. */
+
+typedef struct symgraph symgraph;
+
+struct symgraph
+{
+  /** Identifier for the node: equal to the number of the symbol. */
+  graphid id;
+
+  /** The list of related symbols that have a smaller precedence. */
+  symgraphlink *succ;
+
+  /** The list of related symbols that have a greater precedence. */
+  symgraphlink *pred;
+};
+
+/** Register a new precedence relation as used. */
+
+void register_precedence (graphid first, graphid snd);
+
+/** Print a warning for each symbol whose precedence and/or associativity
+ * is useless. */
+
+void print_precedence_warnings (void);
+
+/*----------------------.
+| Symbol associativity  |
+`----------------------*/
+
+void register_assoc (graphid i, graphid j);
+
 /*-----------------.
 | Semantic types.  |
 `-----------------*/
@@ -190,25 +289,30 @@ typedef struct {
   /** The key, name of the semantic type.  */
   uniqstr tag;
 
-  /** Any \c %destructor declared for this semantic type.  */
-  code_props destructor;
-  /** Any \c %printer declared for this semantic type.  */
-  code_props printer;
+  /** The location of its first occurence.  */
+  location location;
+
+  /** Its status : "undeclared", "used" or "declared".
+      It cannot be "needed".  */
+  status status;
+
+  /** Any \c %destructor and %printer declared for this
+      semantic type.  */
+  code_props props[CODE_PROPS_SIZE];
+
 } semantic_type;
 
 /** Fetch (or create) the semantic type associated to KEY.  */
-semantic_type *semantic_type_from_uniqstr (const uniqstr key);
+semantic_type *semantic_type_from_uniqstr (const uniqstr key,
+                                           const location *loc);
 
 /** Fetch (or create) the semantic type associated to KEY.  */
-semantic_type *semantic_type_get (const char *key);
-
-/** Set the \c destructor associated with \c type.  */
-void semantic_type_destructor_set (semantic_type *type,
-                                   code_props const *destructor);
+semantic_type *semantic_type_get (const char *key, const location *loc);
 
-/** Set the \c printer associated with \c type.  */
-void semantic_type_printer_set (semantic_type *type,
-                                code_props const *printer);
+/** Set the \c destructor or \c printer associated with \c type.  */
+void semantic_type_code_props_set (semantic_type *type,
+                                   code_props_type kind,
+                                   code_props const *code);
 
 /*----------------------------------.
 | Symbol and semantic type tables.  |
@@ -231,19 +335,4 @@ void symbols_check_defined (void);
    #token_translations.  */
 void symbols_pack (void);
 
-
-/*---------------------------------------.
-| Default %destructor's and %printer's.  |
-`---------------------------------------*/
-
-/** Set the default \c \%destructor for tagged values.  */
-void default_tagged_destructor_set (code_props const *destructor);
-/** Set the default \c \%destructor for tagless values.  */
-void default_tagless_destructor_set (code_props const *destructor);
-
-/** Set the default \c \%printer for tagged values.  */
-void default_tagged_printer_set (code_props const *printer);
-/** Set the default \c \%printer for tagless values.  */
-void default_tagless_printer_set (code_props const *printer);
-
 #endif /* !SYMTAB_H_ */