* src/print.c (state_default_rule_compute): New, extracted from...

[bison.git] / src / lalr.c

diff --git a/src/lalr.c b/src/lalr.c
index 9d11c42dd3dd39ce3b6bc6475b3f4d520f11346b..3267172bfcb1d6cf335e47fe753828c7ce496df1 100644 (file)
--- a/src/lalr.c
+++ b/src/lalr.c
@@ -1,5 +1,6 @@
 /* Compute look-ahead criteria for bison,
 /* Compute look-ahead criteria for bison,

-   Copyright 1984, 1986, 1989, 2000 Free Software Foundation, Inc.
+   Copyright (C) 1984, 1986, 1989, 2000, 2001, 2002
+   Free Software Foundation, Inc.

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


@@ -24,306 +25,115 @@
    tokens they accept.  */
 
 #include "system.h"
    tokens they accept.  */
 
 #include "system.h"

+#include "bitset.h"
+#include "bitsetv.h"
+#include "relation.h"
+#include "quotearg.h"
+#include "symtab.h"
+#include "gram.h"
+#include "reader.h"

 #include "types.h"
 #include "LR0.h"
 #include "types.h"
 #include "LR0.h"

-#include "gram.h"

 #include "complain.h"
 #include "lalr.h"
 #include "nullable.h"
 #include "derives.h"
 #include "complain.h"
 #include "lalr.h"
 #include "nullable.h"
 #include "derives.h"

+#include "getargs.h"

 
 

-/* All the decorated states, indexed by the state number.  Warning:
-   there is a state_TABLE in LR0.c, but it is different and static.
-   */
-state_t *state_table = NULL;
+rule_t **LArule = NULL;
+bitsetv LA = NULL;
+size_t nLA;

 
 

-int tokensetsize;
-short *LAruleno;
-unsigned *LA;
-
-short *goto_map;
-short *from_state;
-short *to_state;
+static int ngotos;
+short *goto_map = NULL;
+state_number_t *from_state = NULL;
+state_number_t *to_state = NULL;

 
 

-extern void berror PARAMS ((const char *));
+/* And for the famous F variable, which name is so descriptive that a
+   comment is hardly needed.  <grin>.  */
+static bitsetv F = NULL;

 
 

-static int infinity;
-static int maxrhs;
-static int ngotos;
-static unsigned *F;

 static short **includes;
 static shorts **lookback;
 static short **includes;
 static shorts **lookback;

-static short **R;
-static short *INDEX;
-static short *VERTICES;
-static int top;
-
-
-static void
-traverse (int i)
-{
-  unsigned *fp1;
-  unsigned *fp2;
-  unsigned *fp3;
-  int j;
-  short *rp;
-
-  int height;
-  unsigned *base;
-
-  VERTICES[++top] = i;
-  INDEX[i] = height = top;
-
-  base = F + i * tokensetsize;
-  fp3 = base + tokensetsize;
-
-  rp = R[i];
-  if (rp)
-    {
-      while ((j = *rp++) >= 0)
-       {
-         if (INDEX[j] == 0)
-           traverse (j);
-
-         if (INDEX[i] > INDEX[j])
-           INDEX[i] = INDEX[j];
-
-         fp1 = base;
-         fp2 = F + j * tokensetsize;
-
-         while (fp1 < fp3)
-           *fp1++ |= *fp2++;
-       }
-    }
-
-  if (INDEX[i] == height)
-    {
-      for (;;)
-       {
-         j = VERTICES[top--];
-         INDEX[j] = infinity;
-
-         if (i == j)
-           break;
-
-         fp1 = base;
-         fp2 = F + j * tokensetsize;
-
-         while (fp1 < fp3)
-           *fp2++ = *fp1++;
-       }
-    }
-}
-
-
-static void
-digraph (short **relation)
-{
-  int i;
-
-  infinity = ngotos + 2;
-  INDEX = XCALLOC (short, ngotos + 1);
-  VERTICES = XCALLOC (short, ngotos + 1);
-  top = 0;
-
-  R = relation;
-
-  for (i = 0; i < ngotos; i++)
-    INDEX[i] = 0;
-
-  for (i = 0; i < ngotos; i++)
-    {
-      if (INDEX[i] == 0 && R[i])
-       traverse (i);
-    }
-
-  XFREE (INDEX);
-  XFREE (VERTICES);
-}
-
-static void
-set_state_table (void)
-{
-  /* NSTATES + 1 because lookahead for the pseudo state number NSTATES
-     might be used (see conflicts.c).  It is too opaque for me to
-     provide a probably less hacky implementation. --akim */
-  state_table = XCALLOC (state_t, nstates + 1);
-
-  {
-    core *sp;
-    for (sp = first_state; sp; sp = sp->next)
-      {
-       state_table[sp->number].state = sp;
-       state_table[sp->number].accessing_symbol = sp->accessing_symbol;
-      }
-  }
-
-  {
-    shifts *sp;
-    for (sp = first_shift; sp; sp = sp->next)
-      state_table[sp->number].shift_table = sp;
-  }
-
-  {
-    reductions *rp;
-    for (rp = first_reduction; rp; rp = rp->next)
-      state_table[rp->number].reduction_table = rp;
-  }
-}
-
-
-static void
-set_maxrhs (void)
-{
-  short *itemp;
-  int length;
-  int max;

 
 

-  length = 0;
-  max = 0;
-  for (itemp = ritem; *itemp; itemp++)
-    {
-      if (*itemp > 0)
-       {
-         length++;
-       }
-      else
-       {
-         if (length > max)
-           max = length;
-         length = 0;
-       }
-    }

 
 

-  maxrhs = max;
-}

 
 
 static void
 initialize_LA (void)
 {
 
 
 static void
 initialize_LA (void)
 {

-  int i;
+  state_number_t i;

   int j;
   int j;

-  int count = 0;
-  reductions *rp;
-  shifts *sp;
-  short *np;
-
-  for (i = 0; i < nstates; i++)
-    {
-      int k;
+  rule_t **np;

 
 

-      state_table[i].lookaheads = count;
+  /* Avoid having to special case 0.  */
+  if (!nLA)
+    nLA = 1;

 
 

-      rp = state_table[i].reduction_table;
-      sp = state_table[i].shift_table;
-      if (rp
-         && (rp->nreds > 1
-             || (sp && !ISVAR (state_table[sp->shifts[0]].accessing_symbol))))
-       count += rp->nreds;
-      else
-       state_table[i].consistent = 1;
+  LA = bitsetv_create (nLA, ntokens, BITSET_FIXED);
+  LArule = XCALLOC (rule_t *, nLA);
+  lookback = XCALLOC (shorts *, nLA);

 
 

-      if (sp)
-       for (k = 0; k < sp->nshifts; k++)
-         if (state_table[sp->shifts[k]].accessing_symbol
-             == error_token_number)
-           {
-             state_table[i].consistent = 0;
-             break;
-           }
-    }
-
-  state_table[nstates].lookaheads = count;
-
-  if (count == 0)
-    {
-      LA = XCALLOC (unsigned, 1 * tokensetsize);
-      LAruleno = XCALLOC (short, 1);
-      lookback = XCALLOC (shorts *, 1);
-    }
-  else
-    {
-      LA = XCALLOC (unsigned, count * tokensetsize);
-      LAruleno = XCALLOC (short, count);
-      lookback = XCALLOC (shorts *, count);
-    }
-
-  np = LAruleno;
+  np = LArule;

   for (i = 0; i < nstates; i++)
   for (i = 0; i < nstates; i++)

-    {
-      if (!state_table[i].consistent)
-       {
-         if ((rp = state_table[i].reduction_table))
-           for (j = 0; j < rp->nreds; j++)
-             *np++ = rp->rules[j];
-       }
-    }
+    if (!states[i]->consistent)
+      for (j = 0; j < states[i]->reductions->nreds; j++)
+       *np++ = &rules[states[i]->reductions->rules[j]];

 }
 
 
 static void
 set_goto_map (void)
 {
 }
 
 
 static void
 set_goto_map (void)
 {

-  shifts *sp;
-  int i;
-  int symbol;
-  int k;
+  state_number_t state;

   short *temp_map;
   short *temp_map;

-  int state2;
-  int state1;

 
   goto_map = XCALLOC (short, nvars + 1) - ntokens;
   temp_map = XCALLOC (short, nvars + 1) - ntokens;
 
   ngotos = 0;
 
   goto_map = XCALLOC (short, nvars + 1) - ntokens;
   temp_map = XCALLOC (short, nvars + 1) - ntokens;
 
   ngotos = 0;

-  for (sp = first_shift; sp; sp = sp->next)
+  for (state = 0; state < nstates; ++state)

     {
     {

-      for (i = sp->nshifts - 1; i >= 0; i--)
+      shifts_t *sp = states[state]->shifts;
+      int i;
+      for (i = sp->nshifts - 1; i >= 0 && SHIFT_IS_GOTO (sp, i); --i)

        {
        {

-         symbol = state_table[sp->shifts[i]].accessing_symbol;
-
-         if (ISTOKEN (symbol))
-           break;
-
-         if (ngotos == MAXSHORT)
-           fatal (_("too many gotos (max %d)"), MAXSHORT);
+         if (ngotos == SHRT_MAX)
+           fatal (_("too many gotos (max %d)"), SHRT_MAX);

 
          ngotos++;
 
          ngotos++;

-         goto_map[symbol]++;
+         goto_map[SHIFT_SYMBOL (sp, i)]++;

        }
     }
 
        }
     }
 

-  k = 0;
-  for (i = ntokens; i < nsyms; i++)
-    {
-      temp_map[i] = k;
-      k += goto_map[i];
-    }
+  {
+    int k = 0;
+    int i;
+    for (i = ntokens; i < nsyms; i++)
+      {
+       temp_map[i] = k;
+       k += goto_map[i];
+      }

 
 

-  for (i = ntokens; i < nsyms; i++)
-    goto_map[i] = temp_map[i];
+    for (i = ntokens; i < nsyms; i++)
+      goto_map[i] = temp_map[i];

 
 

-  goto_map[nsyms] = ngotos;
-  temp_map[nsyms] = ngotos;
+    goto_map[nsyms] = ngotos;
+    temp_map[nsyms] = ngotos;
+  }

 
 

-  from_state = XCALLOC (short, ngotos);
-  to_state = XCALLOC (short, ngotos);
+  from_state = XCALLOC (state_number_t, ngotos);
+  to_state = XCALLOC (state_number_t, ngotos);

 
 

-  for (sp = first_shift; sp; sp = sp->next)
+  for (state = 0; state < nstates; ++state)

     {
     {

-      state1 = sp->number;
-      for (i = sp->nshifts - 1; i >= 0; i--)
+      shifts_t *sp = states[state]->shifts;
+      int i;
+      for (i = sp->nshifts - 1; i >= 0 && SHIFT_IS_GOTO (sp, i); --i)

        {
        {

-         state2 = sp->shifts[i];
-         symbol = state_table[state2].accessing_symbol;
-
-         if (ISTOKEN (symbol))
-           break;
-
-         k = temp_map[symbol]++;
-         from_state[k] = state1;
-         to_state[k] = state2;
+         int k = temp_map[SHIFT_SYMBOL (sp, i)]++;
+         from_state[k] = state;
+         to_state[k] = sp->shifts[i];

        }
     }
 
        }
     }
 


@@ -337,12 +147,12 @@ set_goto_map (void)
 `----------------------------------------------------------*/
 
 static int
 `----------------------------------------------------------*/
 
 static int

-map_goto (int state, int symbol)
+map_goto (state_number_t state, symbol_number_t symbol)

 {
   int high;
   int low;
   int middle;
 {
   int high;
   int low;
   int middle;

-  int s;
+  state_number_t s;

 
   low = goto_map[symbol];
   high = goto_map[symbol + 1] - 1;
 
   low = goto_map[symbol];
   high = goto_map[symbol + 1] - 1;


@@ -368,73 +178,43 @@ map_goto (int state, int symbol)
 static void
 initialize_F (void)
 {
 static void
 initialize_F (void)
 {

-  int i;
-  int j;
-  int k;
-  shifts *sp;
-  short *edge;
-  unsigned *rowp;
-  short *rp;
-  short **reads;
-  int nedges;
-  int stateno;
-  int symbol;
-  int nwords;
-
-  nwords = ngotos * tokensetsize;
-  F = XCALLOC (unsigned, nwords);
-
-  reads = XCALLOC (short *, ngotos);
-  edge = XCALLOC (short, ngotos + 1);
-  nedges = 0;
-
-  rowp = F;
-  for (i = 0; i < ngotos; i++)
-    {
-      stateno = to_state[i];
-      sp = state_table[stateno].shift_table;
+  short **reads = XCALLOC (short *, ngotos);
+  short *edge = XCALLOC (short, ngotos + 1);
+  int nedges = 0;

 
 

-      if (sp)
-       {
-         k = sp->nshifts;
-
-         for (j = 0; j < k; j++)
-           {
-             symbol = state_table[sp->shifts[j]].accessing_symbol;
-             if (ISVAR (symbol))
-               break;
-             SETBIT (rowp, symbol);
-           }
+  int i;

 
 

-         for (; j < k; j++)
-           {
-             symbol = state_table[sp->shifts[j]].accessing_symbol;
-             if (nullable[symbol])
-               edge[nedges++] = map_goto (stateno, symbol);
-           }
+  F = bitsetv_create (ngotos, ntokens, BITSET_FIXED);

 
 

-         if (nedges)
-           {
-             reads[i] = rp = XCALLOC (short, nedges + 1);
+  for (i = 0; i < ngotos; i++)
+    {
+      state_number_t stateno = to_state[i];
+      shifts_t *sp = states[stateno]->shifts;

 
 

-             for (j = 0; j < nedges; j++)
-               rp[j] = edge[j];
+      int j;
+      for (j = 0; j < sp->nshifts && SHIFT_IS_SHIFT (sp, j); j++)
+       bitset_set (F[i], SHIFT_SYMBOL (sp, j));

 
 

-             rp[nedges] = -1;
-             nedges = 0;
-           }
+      for (; j < sp->nshifts; j++)
+       {
+         symbol_number_t symbol = SHIFT_SYMBOL (sp, j);
+         if (nullable[symbol])
+           edge[nedges++] = map_goto (stateno, symbol);

        }
 
        }
 

-      rowp += tokensetsize;
+      if (nedges)
+       {
+         reads[i] = XCALLOC (short, nedges + 1);
+         memcpy (reads[i], edge, nedges * sizeof (edge[0]));
+         reads[i][nedges] = -1;
+         nedges = 0;
+       }

     }
 
     }
 

-  digraph (reads);
+  relation_digraph (reads, ngotos, &F);

 
   for (i = 0; i < ngotos; i++)
 
   for (i = 0; i < ngotos; i++)

-    {
-      if (reads[i])
-       XFREE (reads[i]);
-    }
+    XFREE (reads[i]);

 
   XFREE (reads);
   XFREE (edge);
 
   XFREE (reads);
   XFREE (edge);


@@ -442,143 +222,57 @@ initialize_F (void)
 
 
 static void
 
 
 static void

-add_lookback_edge (int stateno, int ruleno, int gotono)
+add_lookback_edge (state_t *state, rule_number_t ruleno, int gotono)

 {
   int i;
 {
   int i;

-  int k;
-  int found;

   shorts *sp;
 
   shorts *sp;
 

-  i = state_table[stateno].lookaheads;
-  k = state_table[stateno + 1].lookaheads;
-  found = 0;
-  while (!found && i < k)
-    {
-      if (LAruleno[i] == ruleno)
-       found = 1;
-      else
-       i++;
-    }
+  for (i = 0; i < state->nlookaheads; ++i)
+    if (state->lookaheads_rule[i]->number == ruleno)
+      break;

 
 

-  assert (found);
+  assert (state->lookaheads_rule[i]->number == ruleno);

 
   sp = XCALLOC (shorts, 1);
 
   sp = XCALLOC (shorts, 1);

-  sp->next = lookback[i];
+  sp->next = lookback[(state->lookaheads - LA) + i];

   sp->value = gotono;
   sp->value = gotono;

-  lookback[i] = sp;
+  lookback[(state->lookaheads - LA) + i] = sp;

 }
 
 
 }
 
 

-static short **
-transpose (short **R_arg, int n)
-{
-  short **new_R;
-  short **temp_R;
-  short *nedges;
-  short *sp;
-  int i;
-  int k;
-
-  nedges = XCALLOC (short, n);
-
-  for (i = 0; i < n; i++)
-    {
-      sp = R_arg[i];
-      if (sp)
-       {
-         while (*sp >= 0)
-           nedges[*sp++]++;
-       }
-    }
-
-  new_R = XCALLOC (short *, n);
-  temp_R = XCALLOC (short *, n);
-
-  for (i = 0; i < n; i++)
-    {
-      k = nedges[i];
-      if (k > 0)
-       {
-         sp = XCALLOC (short, k + 1);
-         new_R[i] = sp;
-         temp_R[i] = sp;
-         sp[k] = -1;
-       }
-    }
-
-  XFREE (nedges);
-
-  for (i = 0; i < n; i++)
-    {
-      sp = R_arg[i];
-      if (sp)
-       {
-         while (*sp >= 0)
-           *temp_R[*sp++]++ = i;
-       }
-    }
-
-  XFREE (temp_R);
-
-  return new_R;
-}
-

 
 static void
 build_relations (void)
 {
 
 static void
 build_relations (void)
 {

+  short *edge = XCALLOC (short, ngotos + 1);
+  state_number_t *states1 = XCALLOC (state_number_t, ritem_longest_rhs () + 1);

   int i;
   int i;

-  int j;
-  int k;
-  short *rulep;
-  short *rp;
-  shifts *sp;
-  int length;
-  int nedges;
-  int done;
-  int state1;
-  int stateno;
-  int symbol1;
-  int symbol2;
-  short *shortp;
-  short *edge;
-  short *states;
-  short **new_includes;

 
   includes = XCALLOC (short *, ngotos);
 
   includes = XCALLOC (short *, ngotos);

-  edge = XCALLOC (short, ngotos + 1);
-  states = XCALLOC (short, maxrhs + 1);

 
   for (i = 0; i < ngotos; i++)
     {
 
   for (i = 0; i < ngotos; i++)
     {

-      nedges = 0;
-      state1 = from_state[i];
-      symbol1 = state_table[to_state[i]].accessing_symbol;
+      int nedges = 0;
+      symbol_number_t symbol1 = states[to_state[i]]->accessing_symbol;
+      rule_number_t *rulep;

 
       for (rulep = derives[symbol1]; *rulep > 0; rulep++)
        {
 
       for (rulep = derives[symbol1]; *rulep > 0; rulep++)
        {

-         length = 1;
-         states[0] = state1;
-         stateno = state1;
+         int done;
+         int length = 1;
+         item_number_t *rp;
+         state_t *state = states[from_state[i]];
+         states1[0] = state->number;

 
 

-         for (rp = ritem + rrhs[*rulep]; *rp > 0; rp++)
+         for (rp = rules[*rulep].rhs; *rp >= 0; rp++)

            {
            {

-             symbol2 = *rp;
-             sp = state_table[stateno].shift_table;
-             k = sp->nshifts;
-
-             for (j = 0; j < k; j++)
-               {
-                 stateno = sp->shifts[j];
-                 if (state_table[stateno].accessing_symbol == symbol2)
-                   break;
-               }
-
-             states[length++] = stateno;
+             state = shifts_to (state->shifts,
+                                item_number_as_symbol_number (*rp));
+             states1[length++] = state->number;

            }
 
            }
 

-         if (!state_table[stateno].consistent)
-           add_lookback_edge (stateno, *rulep, i);
+         if (!state->consistent)
+           add_lookback_edge (state, *rulep, i);

 
          length--;
          done = 0;
 
          length--;
          done = 0;


@@ -589,8 +283,9 @@ build_relations (void)
              /* JF added rp>=ritem &&   I hope to god its right! */
              if (rp >= ritem && ISVAR (*rp))
                {
              /* JF added rp>=ritem &&   I hope to god its right! */
              if (rp >= ritem && ISVAR (*rp))
                {

-                 stateno = states[--length];
-                 edge[nedges++] = map_goto (stateno, *rp);
+                 /* Downcasting from item_number_t to symbol_number_t. */
+                 edge[nedges++] = map_goto (states1[--length],
+                                            item_number_as_symbol_number (*rp));

                  if (nullable[*rp])
                    done = 0;
                }
                  if (nullable[*rp])
                    done = 0;
                }


@@ -599,25 +294,18 @@ build_relations (void)
 
       if (nedges)
        {
 
       if (nedges)
        {

-         includes[i] = shortp = XCALLOC (short, nedges + 1);
+         int j;
+         includes[i] = XCALLOC (short, nedges + 1);

          for (j = 0; j < nedges; j++)
          for (j = 0; j < nedges; j++)

-           shortp[j] = edge[j];
-         shortp[nedges] = -1;
+           includes[i][j] = edge[j];
+         includes[i][nedges] = -1;

        }
     }
 
        }
     }
 

-  new_includes = transpose (includes, ngotos);
-
-  for (i = 0; i < ngotos; i++)
-    if (includes[i])
-      XFREE (includes[i]);
-
-  XFREE (includes);
-
-  includes = new_includes;
-

   XFREE (edge);
   XFREE (edge);

-  XFREE (states);
+  XFREE (states1);
+
+  relation_transpose (&includes, ngotos);

 }
 
 
 }
 
 


@@ -627,13 +315,10 @@ compute_FOLLOWS (void)
 {
   int i;
 
 {
   int i;
 

-  digraph (includes);
+  relation_digraph (includes, ngotos, &F);

 
   for (i = 0; i < ngotos; i++)
 
   for (i = 0; i < ngotos; i++)

-    {
-      if (includes[i])
-       XFREE (includes[i]);
-    }
+    XFREE (includes[i]);

 
   XFREE (includes);
 }
 
   XFREE (includes);
 }


@@ -642,56 +327,125 @@ compute_FOLLOWS (void)
 static void
 compute_lookaheads (void)
 {
 static void
 compute_lookaheads (void)
 {

-  int i;
-  int n;
-  unsigned *fp1;
-  unsigned *fp2;
-  unsigned *fp3;
+  size_t i;

   shorts *sp;
   shorts *sp;

-  unsigned *rowp;
-  shorts *sptmp;               /* JF */

 
 

-  rowp = LA;
-  for (i = 0; i < state_table[nstates].lookaheads; i++)
+  for (i = 0; i < nLA; i++)
+    for (sp = lookback[i]; sp; sp = sp->next)
+      bitset_or (LA[i], LA[i], F[sp->value]);
+
+  /* Free LOOKBACK. */
+  for (i = 0; i < nLA; i++)
+    LIST_FREE (shorts, lookback[i]);
+
+  XFREE (lookback);
+  bitsetv_free (F);
+}
+
+
+/*-------------------------------------------------------------.
+| Count the number of lookaheads required for each state       |
+| (NLOOKAHEADS member).  Compute the total number of LA, NLA.  |
+`-------------------------------------------------------------*/
+
+static void
+states_lookaheads_count (void)
+{
+  state_number_t i;
+  nLA = 0;
+
+  /* Count   */
+  for (i = 0; i < nstates; i++)

     {
     {

-      fp3 = rowp + tokensetsize;
-      for (sp = lookback[i]; sp; sp = sp->next)
-       {
-         fp1 = rowp;
-         fp2 = F + tokensetsize * sp->value;
-         while (fp1 < fp3)
-           *fp1++ |= *fp2++;
-       }
+      int k;
+      int nlookaheads = 0;
+      reductions_t *rp = states[i]->reductions;
+      shifts_t *sp = states[i]->shifts;
+
+      /* We need a lookahead either to distinguish different
+        reductions (i.e., there are two or more), or to distinguish a
+        reduction from a shift.  Otherwise, it is straightforward,
+        and the state is `consistent'.  */
+      if (rp->nreds > 1
+         || (rp->nreds == 1 && sp->nshifts && SHIFT_IS_SHIFT (sp, 0)))
+       nlookaheads += rp->nreds;
+      else
+       states[i]->consistent = 1;
+
+      for (k = 0; k < sp->nshifts; k++)
+       if (SHIFT_IS_ERROR (sp, k))
+         {
+           states[i]->consistent = 0;
+           break;
+         }

 
 

-      rowp = fp3;
+      states[i]->nlookaheads = nlookaheads;
+      nLA += nlookaheads;

     }
     }

+}
+
+
+/*--------------------------------------.
+| Initializing the lookaheads members.  |
+`--------------------------------------*/

 
 

-  for (i = 0; i < state_table[nstates].lookaheads; i++)
+static void
+states_lookaheads_initialize (void)
+{
+  state_number_t i;
+  bitsetv pLA = LA;
+  rule_t **pLArule = LArule;
+
+  /* Initialize the members LOOKAHEADS and LOOKAHEADS_RULE for each
+     state.  */
+  for (i = 0; i < nstates; i++)

     {
     {

-      /* JF removed ref to freed storage */
-      for (sp = lookback[i]; sp; sp = sptmp)
-       {
-         sptmp = sp->next;
-         XFREE (sp);
-       }
+      states[i]->lookaheads = pLA;
+      states[i]->lookaheads_rule = pLArule;
+      pLA += states[i]->nlookaheads;
+      pLArule += states[i]->nlookaheads;

     }
     }

-
-  XFREE (lookback);
-  XFREE (F);

 }
 
 
 }
 
 

+/*---------------------------------------.
+| Output the lookaheads for each state.  |
+`---------------------------------------*/
+
+static void
+lookaheads_print (FILE *out)
+{
+  state_number_t i;
+  int j, k;
+  fprintf (out, "Lookaheads: BEGIN\n");
+  for (i = 0; i < nstates; ++i)
+    {
+      fprintf (out, "State %d: %d lookaheads\n",
+              i, states[i]->nlookaheads);
+
+      for (j = 0; j < states[i]->nlookaheads; ++j)
+       BITSET_EXECUTE (states[i]->lookaheads[j], 0, k,
+       {
+         fprintf (out, "   on %d (%s) -> rule %d\n",
+                  k, symbol_tag_get (symbols[k]),
+                  states[i]->lookaheads_rule[j]->number - 1);
+       });
+    }
+  fprintf (out, "Lookaheads: END\n");
+}
+

 void
 lalr (void)
 {
 void
 lalr (void)
 {

-  tokensetsize = WORDSIZE (ntokens);
-
-  set_state_table ();
-  set_maxrhs ();
+  states_lookaheads_count ();

   initialize_LA ();
   initialize_LA ();

+  states_lookaheads_initialize ();

   set_goto_map ();
   initialize_F ();
   build_relations ();
   compute_FOLLOWS ();
   compute_lookaheads ();
   set_goto_map ();
   initialize_F ();
   build_relations ();
   compute_FOLLOWS ();
   compute_lookaheads ();

+
+  if (trace_flag)
+    lookaheads_print (stderr);

 }
 }