version 3.0

[bison.git] / src / lalr.h

diff --git a/src/lalr.h b/src/lalr.h
index fe148d035fdabd64a5672188d83404f697ed6463..f48331574705c3acaa22908028ca74406060b3ec 100644 (file)
--- a/src/lalr.h
+++ b/src/lalr.h
@@ -1,24 +1,22 @@
 /* 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,
+   2009-2013 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_
@@ -35,24 +33,50 @@
 
 /** 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)
 
@@ -63,11 +87,20 @@ typedef size_t goto_number;
    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_ */