/* Compute lookahead criteria for bison,
- Copyright (C) 1984, 1986, 1989, 2000, 2002, 2004, 2006 Free Software
- Foundation, Inc.
+ Copyright (C) 1984, 1986, 1989, 2000, 2002, 2004, 2006-2007,
+ 2009-2011 Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
- Bison is free software; you can redistribute it and/or modify
+ This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2, or (at your option)
- any later version.
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
- Bison is distributed in the hope that it will be useful,
+ This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
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., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#ifndef LALR_H_
# define LALR_H_
/** 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
+ Find which rules need lookahead in each state, and which lookahead
tokens they accept.
- Builds:
- - #goto_map
- - #from_state
- - #to_state
+ Also builds:
+ - #goto_map
+ - #from_state
+ - #to_state
+ - #goto_follows
*/
void lalr (void);
+/**
+ * Set #nLA and allocate all reduction lookahead sets. Normally invoked by
+ * #lalr.
+ */
+void initialize_LA (void);
+
+/**
+ * Build only:
+ * - #goto_map
+ * - #from_state
+ * - #to_state
+ * Normally invoked by #lalr.
+ */
+void set_goto_map (void);
+
+/**
+ * Update state numbers recorded in #goto_map, #from_state, and #to_state such
+ * that:
+ * - \c nstates_old is the old number of states.
+ * - Where \c i is the old state number, <tt>old_to_new[i]</tt> is either:
+ * - \c nstates_old if state \c i is removed because it is unreachable.
+ * Thus, remove all goto entries involving this state.
+ * - The new state number.
+ */
+void lalr_update_state_numbers (state_number old_to_new[],
+ state_number nstates_old);
+
/** Release the information related to lookahead tokens.
Can be performed once the action tables are computed. */
void lalr_free (void);
-
typedef size_t goto_number;
# define GOTO_NUMBER_MAXIMUM ((goto_number) -1)
TO_STATE of the first of them. */
extern goto_number *goto_map;
-/** State number which a transition leads from. */
+/** The size of #from_state and #to_state. */
+extern goto_number ngotos;
+
+/** State number which a transition leads from. */
extern state_number *from_state;
/** State number it leads to. */
extern state_number *to_state;
+/** Map a state/symbol pair into its numeric representation. */
+goto_number map_goto (state_number s0, symbol_number sym);
+
+/* goto_follows[i] is the set of tokens following goto i. */
+extern bitsetv goto_follows;
+
#endif /* !LALR_H_ */