muscle: factor the computation of variable names

[bison.git] / src / tables.c

diff --git a/src/tables.c b/src/tables.c
index c25d74e75f1a41483ef0b2312f2f561d42135348..f06cba86b9c23d5b3b54829712c02f229a1390d4 100644 (file)
--- a/src/tables.c
+++ b/src/tables.c
@@ -1,30 +1,27 @@
 /* Output the generated parsing program for Bison.
 
 /* Output the generated parsing program for Bison.
 

-   Copyright (C) 1984, 1986, 1989, 1992, 2000, 2001, 2002, 2003, 2004,
-   2005 Free Software Foundation, Inc.
+   Copyright (C) 1984, 1986, 1989, 1992, 2000-2006, 2009-2013 Free
+   Software Foundation, Inc.

 
    This file is part of Bison, the GNU Compiler Compiler.
 
 
    This file is part of Bison, the GNU Compiler Compiler.
 

-   Bison 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.
+   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 3 of the License, or
+   (at your option) any later version.

 
 

-   Bison 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.
+   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
 
    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.  */
-
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

 
 

+#include <config.h>

 #include "system.h"
 
 #include <bitsetv.h>
 #include "system.h"
 
 #include <bitsetv.h>

-#include <quotearg.h>

 
 #include "complain.h"
 #include "conflicts.h"
 
 #include "complain.h"
 #include "conflicts.h"


@@ -32,12 +29,13 @@
 #include "getargs.h"
 #include "gram.h"
 #include "lalr.h"
 #include "getargs.h"
 #include "gram.h"
 #include "lalr.h"

+#include "muscle-tab.h"

 #include "reader.h"
 #include "symtab.h"
 #include "tables.h"
 
 /* Several tables are indexed both by state and nonterminal numbers.
 #include "reader.h"
 #include "symtab.h"
 #include "tables.h"
 
 /* Several tables are indexed both by state and nonterminal numbers.

-   We call such an index a `vector'; i.e., a vector is either a state
+   We call such an index a 'vector'; i.e., a vector is either a state

    or a nonterminal number.
 
    Of course vector_number_t ought to be wide enough to contain
    or a nonterminal number.
 
    Of course vector_number_t ought to be wide enough to contain


@@ -86,24 +84,24 @@ int nvectors;
 static base_number **froms;
 static base_number **tos;
 static unsigned int **conflict_tos;
 static base_number **froms;
 static base_number **tos;
 static unsigned int **conflict_tos;

-static int *tally;
+static size_t *tally;

 static base_number *width;
 
 
 /* For a given state, N = ACTROW[SYMBOL]:
 
 static base_number *width;
 
 
 /* For a given state, N = ACTROW[SYMBOL]:
 

-   If N = 0, stands for `run the default action'.
-   If N = MIN, stands for `raise a syntax error'.
-   If N > 0, stands for `shift SYMBOL and go to n'.
-   If N < 0, stands for `reduce -N'.  */
+   If N = 0, stands for 'run the default action'.
+   If N = MIN, stands for 'raise a syntax error'.
+   If N > 0, stands for 'shift SYMBOL and go to n'.
+   If N < 0, stands for 'reduce -N'.  */

 typedef int action_number;
 #define ACTION_NUMBER_MINIMUM INT_MIN
 
 static action_number *actrow;
 
 /* FROMS and TOS are reordered to be compressed.  ORDER[VECTOR] is the
 typedef int action_number;
 #define ACTION_NUMBER_MINIMUM INT_MIN
 
 static action_number *actrow;
 
 /* FROMS and TOS are reordered to be compressed.  ORDER[VECTOR] is the

-   new vector number of VECTOR.  We skip `empty' vectors (i.e.,
-   TALLY[VECTOR] = 0), and call these `entries'.  */
+   new vector number of VECTOR.  We skip 'empty' vectors (i.e.,
+   TALLY[VECTOR] = 0), and call these 'entries'.  */

 static vector_number *order;
 static int nentries;
 
 static vector_number *order;
 static int nentries;
 


@@ -127,7 +125,7 @@ static int table_size = 32768;
 base_number *table;
 base_number *check;
 /* The value used in TABLE to denote explicit syntax errors
 base_number *table;
 base_number *check;
 /* The value used in TABLE to denote explicit syntax errors

-   (%nonassoc), a negative infinite.  First defaults to ACTION_NUMBER_MININUM,
+   (%nonassoc), a negative infinite.  First defaults to ACTION_NUMBER_MINIMUM,

    but in order to keep small tables, renumbered as TABLE_ERROR, which
    is the smallest (non error) value minus 1.  */
 base_number table_ninf = 0;
    but in order to keep small tables, renumbered as TABLE_ERROR, which
    is the smallest (non error) value minus 1.  */
 base_number table_ninf = 0;


@@ -137,11 +135,11 @@ int high;
 state_number *yydefgoto;
 rule_number *yydefact;
 
 state_number *yydefgoto;
 rule_number *yydefact;
 

-/*----------------------------------------------------------------.
-| If TABLE (and CHECK) appear to be small to be addressed at      |
-| DESIRED, grow them.  Note that TABLE[DESIRED] is to be used, so |
-| the desired size is at least DESIRED + 1.                       |
-`----------------------------------------------------------------*/
+/*-------------------------------------------------------------------.
+| If TABLE, CONFLICT_TABLE, and CHECK are too small to be addressed  |
+| at DESIRED, grow them.  TABLE[DESIRED] can be used, so the desired |
+| size is at least DESIRED + 1.                                      |
+`-------------------------------------------------------------------*/

 
 static void
 table_grow (int desired)
 
 static void
 table_grow (int desired)


@@ -153,11 +151,11 @@ table_grow (int desired)
 
   if (trace_flag & trace_resource)
     fprintf (stderr, "growing table and check from: %d to %d\n",
 
   if (trace_flag & trace_resource)
     fprintf (stderr, "growing table and check from: %d to %d\n",

-            old_size, table_size);
+             old_size, table_size);

 
   table = xnrealloc (table, table_size, sizeof *table);
   conflict_table = xnrealloc (conflict_table, table_size,
 
   table = xnrealloc (table, table_size, sizeof *table);
   conflict_table = xnrealloc (conflict_table, table_size,

-                             sizeof *conflict_table);
+                              sizeof *conflict_table);

   check = xnrealloc (check, table_size, sizeof *check);
 
   for (/* Nothing. */; old_size < table_size; ++old_size)
   check = xnrealloc (check, table_size, sizeof *check);
 
   for (/* Nothing. */; old_size < table_size; ++old_size)


@@ -173,12 +171,12 @@ table_grow (int desired)
 
 /*-------------------------------------------------------------------.
 | For GLR parsers, for each conflicted token in S, as indicated      |
 
 /*-------------------------------------------------------------------.
 | For GLR parsers, for each conflicted token in S, as indicated      |

-| by non-zero entries in CONFLROW, create a list of possible        |
-| reductions that are alternatives to the shift or reduction        |
+| by non-zero entries in CONFLROW, create a list of possible         |
+| reductions that are alternatives to the shift or reduction         |

 | currently recorded for that token in S.  Store the alternative     |
 | currently recorded for that token in S.  Store the alternative     |

-| reductions followed by a 0 in CONFLICT_LIST, updating                     |
+| reductions followed by a 0 in CONFLICT_LIST, updating              |

 | CONFLICT_LIST_CNT, and storing an index to the start of the list   |
 | CONFLICT_LIST_CNT, and storing an index to the start of the list   |

-| back into CONFLROW.                                               |
+| back into CONFLROW.                                                |

 `-------------------------------------------------------------------*/
 
 static void
 `-------------------------------------------------------------------*/
 
 static void


@@ -193,43 +191,41 @@ conflict_row (state *s)
   for (j = 0; j < ntokens; j += 1)
     if (conflrow[j])
       {
   for (j = 0; j < ntokens; j += 1)
     if (conflrow[j])
       {

-       conflrow[j] = conflict_list_cnt;
-
-       /* Find all reductions for token J, and record all that do not
-          match ACTROW[J].  */
-       for (i = 0; i < reds->num; i += 1)
-         if (bitset_test (reds->look_ahead_tokens[i], j)
-             && (actrow[j]
-                 != rule_number_as_item_number (reds->rules[i]->number)))
-           {
-             if (conflict_list_free <= 0)
-               abort ();
-             conflict_list[conflict_list_cnt] = reds->rules[i]->number + 1;
-             conflict_list_cnt += 1;
-             conflict_list_free -= 1;
-           }
-
-       /* Leave a 0 at the end.  */
-       if (conflict_list_free <= 0)
-         abort ();
-       conflict_list[conflict_list_cnt] = 0;
-       conflict_list_cnt += 1;
-       conflict_list_free -= 1;
+        conflrow[j] = conflict_list_cnt;
+
+        /* Find all reductions for token J, and record all that do not
+           match ACTROW[J].  */
+        for (i = 0; i < reds->num; i += 1)
+          if (bitset_test (reds->lookahead_tokens[i], j)
+              && (actrow[j]
+                  != rule_number_as_item_number (reds->rules[i]->number)))
+            {
+              aver (0 < conflict_list_free);
+              conflict_list[conflict_list_cnt] = reds->rules[i]->number + 1;
+              conflict_list_cnt += 1;
+              conflict_list_free -= 1;
+            }
+
+        /* Leave a 0 at the end.  */
+        aver (0 < conflict_list_free);
+        conflict_list[conflict_list_cnt] = 0;
+        conflict_list_cnt += 1;
+        conflict_list_free -= 1;

       }
 }
 
 
 /*------------------------------------------------------------------.
 | Decide what to do for each type of token if seen as the           |
       }
 }
 
 
 /*------------------------------------------------------------------.
 | Decide what to do for each type of token if seen as the           |

-| look-ahead in specified state.  The value returned is used as the |
+| lookahead in specified state.  The value returned is used as the  |

 | default action (yydefact) for the state.  In addition, ACTROW is  |
 | filled with what to do for each kind of token, index by symbol    |
 | number, with zero meaning do the default action.  The value       |
 | default action (yydefact) for the state.  In addition, ACTROW is  |
 | filled with what to do for each kind of token, index by symbol    |
 | number, with zero meaning do the default action.  The value       |

-| ACTION_NUMBER_MINIMUM, a very negative number, means this        |
-| situation is an error.  The parser recognizes this value         |
-| specially.                                                       |
+| ACTION_NUMBER_MINIMUM, a very negative number, means this         |
+| situation is an error.  The parser recognizes this value          |
+| specially.                                                        |

 |                                                                   |
 |                                                                   |

-| This is where conflicts are resolved.  The loop over look-ahead   |
+| This is where conflicts are resolved.  The loop over lookahead    |

 | rules considered lower-numbered rules last, and the last rule     |
 | considered that likes a token gets to handle it.                  |
 |                                                                   |
 | rules considered lower-numbered rules last, and the last rule     |
 | considered that likes a token gets to handle it.                  |
 |                                                                   |


@@ -243,7 +239,7 @@ static rule *
 action_row (state *s)
 {
   int i;
 action_row (state *s)
 {
   int i;

-  rule *default_rule = NULL;
+  rule *default_reduction = NULL;

   reductions *reds = s->reductions;
   transitions *trans = s->transitions;
   errs *errp = s->errs;
   reductions *reds = s->reductions;
   transitions *trans = s->transitions;
   errs *errp = s->errs;


@@ -254,27 +250,27 @@ action_row (state *s)
   for (i = 0; i < ntokens; i++)
     actrow[i] = conflrow[i] = 0;
 
   for (i = 0; i < ntokens; i++)
     actrow[i] = conflrow[i] = 0;
 

-  if (reds->look_ahead_tokens)
+  if (reds->lookahead_tokens)

     {
       int j;
       bitset_iterator biter;
       /* loop over all the rules available here which require
     {
       int j;
       bitset_iterator biter;
       /* loop over all the rules available here which require

-        look-ahead (in reverse order to give precedence to the first
-        rule) */
+         lookahead (in reverse order to give precedence to the first
+         rule) */

       for (i = reds->num - 1; i >= 0; --i)
       for (i = reds->num - 1; i >= 0; --i)

-       /* and find each token which the rule finds acceptable
-          to come next */
-       BITSET_FOR_EACH (biter, reds->look_ahead_tokens[i], j, 0)
-       {
-         /* and record this rule as the rule to use if that
-            token follows.  */
-         if (actrow[j] != 0)
-           {
-             conflicted = true;
-             conflrow[j] = 1;
-           }
-         actrow[j] = rule_number_as_item_number (reds->rules[i]->number);
-       }
+        /* and find each token which the rule finds acceptable
+           to come next */
+        BITSET_FOR_EACH (biter, reds->lookahead_tokens[i], j, 0)
+        {
+          /* and record this rule as the rule to use if that
+             token follows.  */
+          if (actrow[j] != 0)
+            {
+              conflicted = true;
+              conflrow[j] = 1;
+            }
+          actrow[j] = rule_number_as_item_number (reds->rules[i]->number);
+        }

     }
 
   /* Now see which tokens are allowed for shifts in this state.  For
     }
 
   /* Now see which tokens are allowed for shifts in this state.  For


@@ -286,16 +282,16 @@ action_row (state *s)
       state *shift_state = trans->states[i];
 
       if (actrow[sym] != 0)
       state *shift_state = trans->states[i];
 
       if (actrow[sym] != 0)

-       {
-         conflicted = true;
-         conflrow[sym] = 1;
-       }
+        {
+          conflicted = true;
+          conflrow[sym] = 1;
+        }

       actrow[sym] = state_number_as_int (shift_state->number);
 
       /* Do not use any default reduction if there is a shift for
       actrow[sym] = state_number_as_int (shift_state->number);
 
       /* Do not use any default reduction if there is a shift for

-        error */
+         error */

       if (sym == errtoken->number)
       if (sym == errtoken->number)

-       nodefault = true;
+        nodefault = true;

     }
 
   /* See which tokens are an explicit error in this state (due to
     }
 
   /* See which tokens are an explicit error in this state (due to


@@ -307,62 +303,74 @@ action_row (state *s)
       actrow[sym->number] = ACTION_NUMBER_MINIMUM;
     }
 
       actrow[sym->number] = ACTION_NUMBER_MINIMUM;
     }
 

+  /* Turn off default reductions where requested by the user.  See
+     state_lookahead_tokens_count in lalr.c to understand when states are
+     labeled as consistent.  */
+  {
+    char *default_reductions =
+      muscle_percent_define_get ("lr.default-reduction");
+    if (STRNEQ (default_reductions, "most") && !s->consistent)
+      nodefault = true;
+    free (default_reductions);
+  }
+

   /* Now find the most common reduction and make it the default action
      for this state.  */
 
   if (reds->num >= 1 && !nodefault)
     {
       if (s->consistent)
   /* Now find the most common reduction and make it the default action
      for this state.  */
 
   if (reds->num >= 1 && !nodefault)
     {
       if (s->consistent)

-       default_rule = reds->rules[0];
+        default_reduction = reds->rules[0];

       else
       else

-       {
-         int max = 0;
-         for (i = 0; i < reds->num; i++)
-           {
-             int count = 0;
-             rule *r = reds->rules[i];
-             symbol_number j;
-
-             for (j = 0; j < ntokens; j++)
-               if (actrow[j] == rule_number_as_item_number (r->number))
-                 count++;
-
-             if (count > max)
-               {
-                 max = count;
-                 default_rule = r;
-               }
-           }
-
-         /* GLR parsers need space for conflict lists, so we can't
-            default conflicted entries.  For non-conflicted entries
-            or as long as we are not building a GLR parser,
-            actions that match the default are replaced with zero,
-            which means "use the default". */
-
-         if (max > 0)
-           {
-             int j;
-             for (j = 0; j < ntokens; j++)
-               if (actrow[j] == rule_number_as_item_number (default_rule->number)
-                   && ! (nondeterministic_parser && conflrow[j]))
-                 actrow[j] = 0;
-           }
-       }
+        {
+          int max = 0;
+          for (i = 0; i < reds->num; i++)
+            {
+              int count = 0;
+              rule *r = reds->rules[i];
+              symbol_number j;
+
+              for (j = 0; j < ntokens; j++)
+                if (actrow[j] == rule_number_as_item_number (r->number))
+                  count++;
+
+              if (count > max)
+                {
+                  max = count;
+                  default_reduction = r;
+                }
+            }
+
+          /* GLR parsers need space for conflict lists, so we can't
+             default conflicted entries.  For non-conflicted entries
+             or as long as we are not building a GLR parser,
+             actions that match the default are replaced with zero,
+             which means "use the default". */
+
+          if (max > 0)
+            {
+              int j;
+              for (j = 0; j < ntokens; j++)
+                if (actrow[j]
+                    == rule_number_as_item_number (default_reduction->number)
+                    && ! (nondeterministic_parser && conflrow[j]))
+                  actrow[j] = 0;
+            }
+        }

     }
 
     }
 

-  /* If have no default rule, the default is an error.
+  /* If have no default reduction, the default is an error.

      So replace any action which says "error" with "use default".  */
 
      So replace any action which says "error" with "use default".  */
 

-  if (!default_rule)
+  if (!default_reduction)

     for (i = 0; i < ntokens; i++)
       if (actrow[i] == ACTION_NUMBER_MINIMUM)
     for (i = 0; i < ntokens; i++)
       if (actrow[i] == ACTION_NUMBER_MINIMUM)

-       actrow[i] = 0;
+        actrow[i] = 0;

 
   if (conflicted)
     conflict_row (s);
 
 
   if (conflicted)
     conflict_row (s);
 

-  return default_rule;
+  return default_reduction;

 }
 
 
 }
 
 


@@ -374,45 +382,40 @@ static void
 save_row (state_number s)
 {
   symbol_number i;
 save_row (state_number s)
 {
   symbol_number i;

-  int count;
-  base_number *sp;
-  base_number *sp1;
-  base_number *sp2;
-  unsigned int *sp3;

 
   /* Number of non default actions in S.  */
 
   /* Number of non default actions in S.  */

-  count = 0;
+  size_t count = 0;

   for (i = 0; i < ntokens; i++)
     if (actrow[i] != 0)
       count++;
 
   for (i = 0; i < ntokens; i++)
     if (actrow[i] != 0)
       count++;
 

-  if (count == 0)
-    return;
-
-  /* Allocate non defaulted actions.  */
-  froms[s] = sp = sp1 = xnmalloc (count, sizeof *sp1);
-  tos[s] = sp2 = xnmalloc (count, sizeof *sp2);
-  conflict_tos[s] = sp3 =
-    nondeterministic_parser ? xnmalloc (count, sizeof *sp3) : NULL;
-
-  /* Store non defaulted actions.  */
-  for (i = 0; i < ntokens; i++)
-    if (actrow[i] != 0)
-      {
-       *sp1++ = i;
-       *sp2++ = actrow[i];
-       if (nondeterministic_parser)
-         *sp3++ = conflrow[i];
-      }
-
-  tally[s] = count;
-  width[s] = sp1[-1] - sp[0] + 1;
+  if (count)
+    {
+      /* Allocate non defaulted actions.  */
+      base_number *sp1 = froms[s] = xnmalloc (count, sizeof *sp1);
+      base_number *sp2 = tos[s] = xnmalloc (count, sizeof *sp2);
+      unsigned int *sp3 = conflict_tos[s] =
+        nondeterministic_parser ? xnmalloc (count, sizeof *sp3) : NULL;
+
+      /* Store non defaulted actions.  */
+      for (i = 0; i < ntokens; i++)
+        if (actrow[i] != 0)
+          {
+            *sp1++ = i;
+            *sp2++ = actrow[i];
+            if (nondeterministic_parser)
+              *sp3++ = conflrow[i];
+          }
+
+      tally[s] = count;
+      width[s] = sp1[-1] - froms[s][0] + 1;
+    }

 }
 
 
 /*------------------------------------------------------------------.
 | Figure out the actions for the specified state, indexed by        |
 }
 
 
 /*------------------------------------------------------------------.
 | Figure out the actions for the specified state, indexed by        |

-| look-ahead token type.                                            |
+| lookahead token type.                                             |

 |                                                                   |
 | The YYDEFACT table is output now.  The detailed info is saved for |
 | putting into YYTABLE later.                                       |
 |                                                                   |
 | The YYDEFACT table is output now.  The detailed info is saved for |
 | putting into YYTABLE later.                                       |


@@ -421,10 +424,6 @@ save_row (state_number s)
 static void
 token_actions (void)
 {
 static void
 token_actions (void)
 {

-  state_number i;
-  symbol_number j;
-  rule_number r;
-

   int nconflict = nondeterministic_parser ? conflicts_total_count () : 0;
 
   yydefact = xnmalloc (nstates, sizeof *yydefact);
   int nconflict = nondeterministic_parser ? conflicts_total_count () : 0;
 
   yydefact = xnmalloc (nstates, sizeof *yydefact);


@@ -438,28 +437,34 @@ token_actions (void)
 
   /* Find the rules which are reduced.  */
   if (!nondeterministic_parser)
 
   /* Find the rules which are reduced.  */
   if (!nondeterministic_parser)

-    for (r = 0; r < nrules; ++r)
-      rules[r].useful = false;
-
-  for (i = 0; i < nstates; ++i)

     {
     {

-      rule *default_rule = action_row (states[i]);
-      yydefact[i] = default_rule ? default_rule->number + 1 : 0;
-      save_row (i);
-
-      /* Now that the parser was computed, we can find which rules are
-        really reduced, and which are not because of SR or RR
-        conflicts.  */
-      if (!nondeterministic_parser)
-       {
-         for (j = 0; j < ntokens; ++j)
-           if (actrow[j] < 0 && actrow[j] != ACTION_NUMBER_MINIMUM)
-             rules[item_number_as_rule_number (actrow[j])].useful = true;
-         if (yydefact[i])
-           rules[yydefact[i] - 1].useful = true;
-       }
+      rule_number r;
+      for (r = 0; r < nrules; ++r)
+        rules[r].useful = false;

     }
 
     }
 

+  {
+    state_number i;
+    for (i = 0; i < nstates; ++i)
+      {
+        rule *default_reduction = action_row (states[i]);
+        yydefact[i] = default_reduction ? default_reduction->number + 1 : 0;
+        save_row (i);
+
+        /* Now that the parser was computed, we can find which rules are
+           really reduced, and which are not because of SR or RR
+           conflicts.  */
+        if (!nondeterministic_parser)
+          {
+            symbol_number j;
+            for (j = 0; j < ntokens; ++j)
+              if (actrow[j] < 0 && actrow[j] != ACTION_NUMBER_MINIMUM)
+                rules[item_number_as_rule_number (actrow[j])].useful = true;
+            if (yydefact[i])
+              rules[yydefact[i] - 1].useful = true;
+          }
+      }
+  }

   free (actrow);
   free (conflrow);
 }
   free (actrow);
   free (conflrow);
 }


@@ -478,72 +483,68 @@ static void
 save_column (symbol_number sym, state_number default_state)
 {
   goto_number i;
 save_column (symbol_number sym, state_number default_state)
 {
   goto_number i;

-  base_number *sp;
-  base_number *sp1;
-  base_number *sp2;
-  int count;
-  vector_number symno = symbol_number_to_vector_number (sym);
-

   goto_number begin = goto_map[sym - ntokens];
   goto_number end = goto_map[sym - ntokens + 1];
 
   /* Number of non default GOTO.  */
   goto_number begin = goto_map[sym - ntokens];
   goto_number end = goto_map[sym - ntokens + 1];
 
   /* Number of non default GOTO.  */

-  count = 0;
+  size_t count = 0;

   for (i = begin; i < end; i++)
     if (to_state[i] != default_state)
       count++;
 
   for (i = begin; i < end; i++)
     if (to_state[i] != default_state)
       count++;
 

-  if (count == 0)
-    return;
-
-  /* Allocate room for non defaulted gotos.  */
-  froms[symno] = sp = sp1 = xnmalloc (count, sizeof *sp1);
-  tos[symno] = sp2 = xnmalloc (count, sizeof *sp2);
-
-  /* Store the state numbers of the non defaulted gotos.  */
-  for (i = begin; i < end; i++)
-    if (to_state[i] != default_state)
-      {
-       *sp1++ = from_state[i];
-       *sp2++ = to_state[i];
-      }
-
-  tally[symno] = count;
-  width[symno] = sp1[-1] - sp[0] + 1;
+  if (count)
+    {
+      /* Allocate room for non defaulted gotos.  */
+      vector_number symno = symbol_number_to_vector_number (sym);
+      base_number *sp1 = froms[symno] = xnmalloc (count, sizeof *sp1);
+      base_number *sp2 = tos[symno] = xnmalloc (count, sizeof *sp2);
+
+      /* Store the state numbers of the non defaulted gotos.  */
+      for (i = begin; i < end; i++)
+        if (to_state[i] != default_state)
+          {
+            *sp1++ = from_state[i];
+            *sp2++ = to_state[i];
+          }
+
+      tally[symno] = count;
+      width[symno] = sp1[-1] - froms[symno][0] + 1;
+    }

 }
 
 
 }
 
 

-/*-------------------------------------------------------------.
-| Return `the' most common destination GOTO on SYM (a nterm).  |
-`-------------------------------------------------------------*/
+/*----------------------------------------------------------------.
+| The default state for SYM: the state which is 'the' most common |
+| GOTO destination on SYM (an nterm).                             |
+`----------------------------------------------------------------*/

 
 static state_number
 default_goto (symbol_number sym, size_t state_count[])
 {
 
 static state_number
 default_goto (symbol_number sym, size_t state_count[])
 {

-  state_number s;
-  goto_number i;
-  goto_number m = goto_map[sym - ntokens];
-  goto_number n = goto_map[sym - ntokens + 1];
-  state_number default_state = -1;
-  size_t max = 0;
-
-  if (m == n)
-    return -1;
-
-  for (s = 0; s < nstates; s++)
-    state_count[s] = 0;
-
-  for (i = m; i < n; i++)
-    state_count[to_state[i]]++;
-
-  for (s = 0; s < nstates; s++)
-    if (state_count[s] > max)
-      {
-       max = state_count[s];
-       default_state = s;
-      }
+  goto_number begin = goto_map[sym - ntokens];
+  goto_number end = goto_map[sym - ntokens + 1];
+  state_number res = -1;

 
 

-  return default_state;
+  if (begin != end)
+    {
+      size_t max = 0;
+      goto_number i;
+      state_number s;
+
+      for (s = 0; s < nstates; s++)
+        state_count[s] = 0;
+
+      for (i = begin; i < end; i++)
+        state_count[to_state[i]]++;
+
+      for (s = 0; s < nstates; s++)
+        if (max < state_count[s])
+          {
+            max = state_count[s];
+            res = s;
+          }
+    }
+  return res;

 }
 
 
 }
 
 


@@ -588,29 +589,29 @@ sort_actions (void)
   nentries = 0;
 
   for (i = 0; i < nvectors; i++)
   nentries = 0;
 
   for (i = 0; i < nvectors; i++)

-    if (tally[i] > 0)
+    if (0 < tally[i])

       {
       {

-       int k;
-       int t = tally[i];
-       int w = width[i];
-       int j = nentries - 1;
+        int k;
+        size_t t = tally[i];
+        int w = width[i];
+        int j = nentries - 1;

 
 

-       while (j >= 0 && (width[order[j]] < w))
-         j--;
+        while (0 <= j && width[order[j]] < w)
+          j--;

 
 

-       while (j >= 0 && (width[order[j]] == w) && (tally[order[j]] < t))
-         j--;
+        while (0 <= j && width[order[j]] == w && tally[order[j]] < t)
+          j--;

 
 

-       for (k = nentries - 1; k > j; k--)
-         order[k + 1] = order[k];
+        for (k = nentries - 1; k > j; k--)
+          order[k + 1] = order[k];

 
 

-       order[j + 1] = i;
-       nentries++;
+        order[j + 1] = i;
+        nentries++;

       }
 }
 
 
       }
 }
 
 

-/* If VECTOR is a state which actions (reflected by FROMS, TOS, TALLY
+/* If VECTOR is a state whose actions (reflected by FROMS, TOS, TALLY

    and WIDTH of VECTOR) are common to a previous state, return this
    state number.
 
    and WIDTH of VECTOR) are common to a previous state, return this
    state number.
 


@@ -620,46 +621,43 @@ static state_number
 matching_state (vector_number vector)
 {
   vector_number i = order[vector];
 matching_state (vector_number vector)
 {
   vector_number i = order[vector];

-  int t;
-  int w;
-  int prev;
-

   /* If VECTOR is a nterm, return -1.  */
   /* If VECTOR is a nterm, return -1.  */

-  if (nstates <= i)
-    return -1;
-
-  t = tally[i];
-  w = width[i];
-
-  /* If VECTOR has GLR conflicts, return -1 */
-  if (conflict_tos[i] != NULL)
-    {
-      int j;
-      for (j = 0; j < t; j += 1)
-       if (conflict_tos[i][j] != 0)
-         return -1;
-    }
-
-  for (prev = vector - 1; prev >= 0; prev--)
+  if (i < nstates)

     {
     {

-      vector_number j = order[prev];
-      int k;
-      int match = 1;
-
-      /* Given how ORDER was computed, if the WIDTH or TALLY is
-        different, there cannot be a matching state.  */
-      if (width[j] != w || tally[j] != t)
-       return -1;
-
-      for (k = 0; match && k < t; k++)
-       if (tos[j][k] != tos[i][k] || froms[j][k] != froms[i][k]
-           || (conflict_tos[j] != NULL && conflict_tos[j][k] != 0))
-         match = 0;
-
-      if (match)
-       return j;
+      size_t t = tally[i];
+      int w = width[i];
+      int prev;
+
+      /* If VECTOR has GLR conflicts, return -1 */
+      if (conflict_tos[i] != NULL)
+        {
+          int j;
+          for (j = 0; j < t; j += 1)
+            if (conflict_tos[i][j] != 0)
+              return -1;
+        }
+
+      for (prev = vector - 1; 0 <= prev; prev--)
+        {
+          vector_number j = order[prev];
+          /* Given how ORDER was computed, if the WIDTH or TALLY is
+             different, there cannot be a matching state.  */
+          if (width[j] != w || tally[j] != t)
+            return -1;
+          else
+            {
+              bool match = true;
+              int k;
+              for (k = 0; match && k < t; k++)
+                if (tos[j][k] != tos[i][k]
+                    || froms[j][k] != froms[i][k]
+                    || (conflict_tos[j] != NULL && conflict_tos[j][k] != 0))
+                  match = false;
+              if (match)
+                return j;
+            }
+        }

     }
     }

-

   return -1;
 }
 
   return -1;
 }
 


@@ -667,60 +665,59 @@ matching_state (vector_number vector)
 static base_number
 pack_vector (vector_number vector)
 {
 static base_number
 pack_vector (vector_number vector)
 {

+  base_number res;

   vector_number i = order[vector];
   vector_number i = order[vector];

-  int j;
-  int t = tally[i];
-  int loc = 0;
+  size_t t = tally[i];

   base_number *from = froms[i];
   base_number *to = tos[i];
   unsigned int *conflict_to = conflict_tos[i];
 
   base_number *from = froms[i];
   base_number *to = tos[i];
   unsigned int *conflict_to = conflict_tos[i];
 

-  if (!t)
-    abort ();
+  aver (t != 0);

 
 

-  for (j = lowzero - from[0]; ; j++)
+  for (res = lowzero - from[0]; ; res++)

     {
     {

-      int k;

       bool ok = true;
       bool ok = true;

-
-      if (table_size <= j)
-       abort ();
-
-      for (k = 0; ok && k < t; k++)
-       {
-         loc = j + state_number_as_int (from[k]);
-         if (table_size <= loc)
-           table_grow (loc);
-
-         if (table[loc] != 0)
-           ok = false;
-       }
-
-      for (k = 0; ok && k < vector; k++)
-       if (pos[k] == j)
-         ok = false;
+      aver (res < table_size);
+      {
+        int k;
+        for (k = 0; ok && k < t; k++)
+          {
+            int loc = res + state_number_as_int (from[k]);
+            if (table_size <= loc)
+              table_grow (loc);
+
+            if (table[loc] != 0)
+              ok = false;
+          }
+
+        if (ok)
+          for (k = 0; k < vector; k++)
+            if (pos[k] == res)
+              ok = false;
+      }

 
       if (ok)
 
       if (ok)

-       {
-         for (k = 0; k < t; k++)
-           {
-             loc = j + from[k];
-             table[loc] = to[k];
-             if (nondeterministic_parser && conflict_to != NULL)
-               conflict_table[loc] = conflict_to[k];
-             check[loc] = from[k];
-           }
-
-         while (table[lowzero] != 0)
-           lowzero++;
-
-         if (loc > high)
-           high = loc;
-
-         if (! (BASE_MINIMUM <= j && j <= BASE_MAXIMUM))
-           abort ();
-         return j;
-       }
+        {
+          int loc;
+          int k;
+          for (k = 0; k < t; k++)
+            {
+              loc = res + state_number_as_int (from[k]);
+              table[loc] = to[k];
+              if (nondeterministic_parser && conflict_to != NULL)
+                conflict_table[loc] = conflict_to[k];
+              check[loc] = from[k];
+            }
+
+          while (table[lowzero] != 0)
+            lowzero++;
+
+          if (high < loc)
+            high = loc;
+
+          aver (BASE_MINIMUM <= res && res <= BASE_MAXIMUM);
+          return res;
+        }

     }
 }
 
     }
 }
 


@@ -778,11 +775,11 @@ pack_table (void)
       base_number place;
 
       if (s < 0)
       base_number place;
 
       if (s < 0)

-       /* A new set of state actions, or a nonterminal.  */
-       place = pack_vector (i);
+        /* A new set of state actions, or a nonterminal.  */
+        place = pack_vector (i);

       else
       else

-       /* Action of I were already coded for S.  */
-       place = base[s];
+        /* Action of I were already coded for S.  */
+        place = base[s];

 
       pos[i] = place;
       base[order[i]] = place;
 
       pos[i] = place;
       base[order[i]] = place;


@@ -810,9 +807,8 @@ tables_generate (void)
   /* This is a poor way to make sure the sizes are properly
      correlated.  In particular the signedness is not taken into
      account.  But it's not useless.  */
   /* This is a poor way to make sure the sizes are properly
      correlated.  In particular the signedness is not taken into
      account.  But it's not useless.  */

-  verify (sizes_are_properly_correlated,
-         (sizeof nstates <= sizeof nvectors
-          && sizeof nvars <= sizeof nvectors));
+  verify (sizeof nstates <= sizeof nvectors
+          && sizeof nvars <= sizeof nvectors);

 
   nvectors = state_number_as_int (nstates) + nvars;
 
 
   nvectors = state_number_as_int (nstates) + nvars;