-/* Compute look-ahead criteria for bison,
+/* Compute lookahead criteria for bison,
- Copyright (C) 1984, 1986, 1989, 2000, 2002, 2004 Free Software
+ Copyright (C) 1984, 1986, 1989, 2000, 2002, 2004, 2006 Free Software
Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
You should have received a copy of the GNU General Public License
along with Bison; see the file COPYING. If not, write to
- the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA. */
#ifndef LALR_H_
# define LALR_H_
/* Import the definition of CORE, TRANSITIONS and REDUCTIONS. */
# include "state.h"
-/* Compute how to make the finite state machine deterministic; find
+
+/** Build the LALR(1) automaton.
+
+ Compute how to make the finite state machine deterministic; find
which rules need lookahead in each state, and which lookahead
- tokens they accept. */
+ tokens they accept.
+ Builds:
+ - #goto_map
+ - #from_state
+ - #to_state
+*/
void lalr (void);
-/* Release the information related to lookaheads. Can be performed
- once the action tables are computed. */
-void lalr_free (void);
+/** Release the information related to lookahead tokens.
+ Can be performed once the action tables are computed. */
+void lalr_free (void);
-/* lalr() builds these data structures. */
-/* GOTO_MAP, FROM_STATE and TO_STATE -- record each shift transition
- which accepts a variable (a nonterminal).
+typedef size_t goto_number;
+# define GOTO_NUMBER_MAXIMUM ((goto_number) -1)
- FROM_STATE[T] -- state number which a transition leads from.
- TO_STATE[T] -- state number it leads to.
+/** Index into #from_state and #to_state.
All the transitions that accept a particular variable are grouped
together and GOTO_MAP[I - NTOKENS] is the index in FROM_STATE and
TO_STATE of the first of them. */
-
-typedef short int goto_number;
-# define GOTO_NUMBER_MAXIMUM SHRT_MAX
-
extern goto_number *goto_map;
+
+/** State number which a transition leads from. */
extern state_number *from_state;
+
+/** State number it leads to. */
extern state_number *to_state;