bump to 2012 in skeletons.

[bison.git] / src / LR0.c

diff --git a/src/LR0.c b/src/LR0.c
index ae39b7ce5033433d5d5d9e8748540de4e1396a71..37bfe8137acc0623992628ee05078d065fb7322b 100644 (file)
--- a/src/LR0.c
+++ b/src/LR0.c
@@ -1,33 +1,31 @@
-/* Generate the nondeterministic finite state machine for Bison.
+/* Generate the LR(0) parser states for Bison.

 
 

-   Copyright (C) 1984, 1986, 1989, 2000, 2001, 2002 Free Software
-   Foundation, Inc.
+   Copyright (C) 1984, 1986, 1989, 2000-2002, 2004-2007, 2009-2012 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
+   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
    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
    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., 59 Temple Place - Suite 330,
-   Boston, MA 02111-1307, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

 
 
 /* See comments in state.h for the data structures that represent it.
    The entry point is generate_states.  */
 
 
 
 /* See comments in state.h for the data structures that represent it.
    The entry point is generate_states.  */
 

+#include <config.h>

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

-#include <quotearg.h>

 
 #include "LR0.h"
 #include "closure.h"
 
 #include "LR0.h"
 #include "closure.h"


@@ -59,18 +57,13 @@ static state_list *last_state = NULL;
 static state *
 state_list_append (symbol_number sym, size_t core_size, item_number *core)
 {
 static state *
 state_list_append (symbol_number sym, size_t core_size, item_number *core)
 {

-  state_list *node = MALLOC (node, 1);
+  state_list *node = xmalloc (sizeof *node);

   state *s = state_new (sym, core_size, core);
 
   if (trace_flag & trace_automaton)
     fprintf (stderr, "state_list_append (state = %d, symbol = %d (%s))\n",
             nstates, sym, symbols[sym]->tag);
 
   state *s = state_new (sym, core_size, core);
 
   if (trace_flag & trace_automaton)
     fprintf (stderr, "state_list_append (state = %d, symbol = %d (%s))\n",
             nstates, sym, symbols[sym]->tag);
 

-  /* If this is the endtoken, and this is not the initial state, then
-     this is the final state.  */
-  if (sym == 0 && first_state)
-    final_state = s;
-

   node->next = NULL;
   node->state = s;
 
   node->next = NULL;
   node->state = s;
 


@@ -84,14 +77,14 @@ state_list_append (symbol_number sym, size_t core_size, item_number *core)
 }
 
 static int nshifts;
 }
 
 static int nshifts;

-static symbol_number *shift_symbol = NULL;
+static symbol_number *shift_symbol;

 
 

-static rule **redset = NULL;
-static state **shiftset = NULL;
+static rule **redset;
+static state **shiftset;

 
 

-static item_number **kernel_base = NULL;
-static int *kernel_size = NULL;
-static item_number *kernel_items = NULL;
+static item_number **kernel_base;
+static int *kernel_size;
+static item_number *kernel_items;

 
 \f
 static void
 
 \f
 static void


@@ -105,8 +98,9 @@ allocate_itemsets (void)
      Note that useless productions (hence useless nonterminals) are
      browsed too, hence we need to allocate room for _all_ the
      symbols.  */
      Note that useless productions (hence useless nonterminals) are
      browsed too, hence we need to allocate room for _all_ the
      symbols.  */

-  int count = 0;
-  short *symbol_count = CALLOC (symbol_count, nsyms + nuseless_nonterminals);
+  size_t count = 0;
+  size_t *symbol_count = xcalloc (nsyms + nuseless_nonterminals,
+                                 sizeof *symbol_count);

 
   for (r = 0; r < nrules; ++r)
     for (rhsp = rules[r].rhs; *rhsp >= 0; ++rhsp)
 
   for (r = 0; r < nrules; ++r)
     for (rhsp = rules[r].rhs; *rhsp >= 0; ++rhsp)


@@ -121,9 +115,8 @@ allocate_itemsets (void)
      appears as an item, which is SYMBOL_COUNT[S].
      We allocate that much space for each symbol.  */
 
      appears as an item, which is SYMBOL_COUNT[S].
      We allocate that much space for each symbol.  */
 

-  CALLOC (kernel_base, nsyms);
-  if (count)
-    CALLOC (kernel_items, count);
+  kernel_base = xnmalloc (nsyms, sizeof *kernel_base);
+  kernel_items = xnmalloc (count, sizeof *kernel_items);

 
   count = 0;
   for (i = 0; i < nsyms; i++)
 
   count = 0;
   for (i = 0; i < nsyms; i++)


@@ -133,7 +126,7 @@ allocate_itemsets (void)
     }
 
   free (symbol_count);
     }
 
   free (symbol_count);

-  CALLOC (kernel_size, nsyms);
+  kernel_size = xnmalloc (nsyms, sizeof *kernel_size);

 }
 
 
 }
 
 


@@ -142,10 +135,10 @@ allocate_storage (void)
 {
   allocate_itemsets ();
 
 {
   allocate_itemsets ();
 

-  CALLOC (shiftset, nsyms);
-  CALLOC (redset, nrules);
+  shiftset = xnmalloc (nsyms, sizeof *shiftset);
+  redset = xnmalloc (nrules, sizeof *redset);

   state_hash_new ();
   state_hash_new ();

-  CALLOC (shift_symbol, nsyms);
+  shift_symbol = xnmalloc (nsyms, sizeof *shift_symbol);

 }
 
 
 }
 
 


@@ -157,7 +150,7 @@ free_storage (void)
   free (shiftset);
   free (kernel_base);
   free (kernel_size);
   free (shiftset);
   free (kernel_base);
   free (kernel_size);

-  XFREE (kernel_items);
+  free (kernel_items);

   state_hash_free ();
 }
 
   state_hash_free ();
 }
 


@@ -173,23 +166,26 @@ free_storage (void)
 | shifted.  For each symbol in the grammar, kernel_base[symbol]  |
 | points to a vector of item numbers activated if that symbol is |
 | shifted, and kernel_size[symbol] is their numbers.             |
 | shifted.  For each symbol in the grammar, kernel_base[symbol]  |
 | points to a vector of item numbers activated if that symbol is |
 | shifted, and kernel_size[symbol] is their numbers.             |

+|                                                                |
+| itemset is sorted on item index in ritem, which is sorted on   |
+| rule number.  Compute each kernel_base[symbol] with the same   |
+| sort.                                                          |

 `---------------------------------------------------------------*/
 
 static void
 new_itemsets (state *s)
 {
 `---------------------------------------------------------------*/
 
 static void
 new_itemsets (state *s)
 {

-  int i;
+  size_t i;

 
   if (trace_flag & trace_automaton)
     fprintf (stderr, "Entering new_itemsets, state = %d\n", s->number);
 
 
   if (trace_flag & trace_automaton)
     fprintf (stderr, "Entering new_itemsets, state = %d\n", s->number);
 

-  for (i = 0; i < nsyms; i++)
-    kernel_size[i] = 0;
+  memset (kernel_size, 0, nsyms * sizeof *kernel_size);

 
   nshifts = 0;
 
 
   nshifts = 0;
 

-  for (i = 0; i < nritemset; ++i)
-    if (ritem[itemset[i]] >= 0)
+  for (i = 0; i < nitemset; ++i)
+    if (item_number_is_symbol_number (ritem[itemset[i]]))

       {
        symbol_number sym = item_number_as_symbol_number (ritem[itemset[i]]);
        if (!kernel_size[sym])
       {
        symbol_number sym = item_number_as_symbol_number (ritem[itemset[i]]);
        if (!kernel_size[sym])


@@ -214,20 +210,20 @@ new_itemsets (state *s)
 static state *
 get_state (symbol_number sym, size_t core_size, item_number *core)
 {
 static state *
 get_state (symbol_number sym, size_t core_size, item_number *core)
 {

-  state *sp;
+  state *s;

 
   if (trace_flag & trace_automaton)
     fprintf (stderr, "Entering get_state, symbol = %d (%s)\n",
             sym, symbols[sym]->tag);
 
 
   if (trace_flag & trace_automaton)
     fprintf (stderr, "Entering get_state, symbol = %d (%s)\n",
             sym, symbols[sym]->tag);
 

-  sp = state_hash_lookup (core_size, core);
-  if (!sp)
-    sp = state_list_append (sym, core_size, core);
+  s = state_hash_lookup (core_size, core);
+  if (!s)
+    s = state_list_append (sym, core_size, core);

 
   if (trace_flag & trace_automaton)
 
   if (trace_flag & trace_automaton)

-    fprintf (stderr, "Exiting get_state => %d\n", sp->number);
+    fprintf (stderr, "Exiting get_state => %d\n", s->number);

 
 

-  return sp;
+  return s;

 }
 
 /*---------------------------------------------------------------.
 }
 
 /*---------------------------------------------------------------.


@@ -251,7 +247,7 @@ append_states (state *s)
     {
       symbol_number sym = shift_symbol[i];
       int j;
     {
       symbol_number sym = shift_symbol[i];
       int j;

-      for (j = i; 0 < j && sym < shift_symbol [j - 1]; j--)
+      for (j = i; 0 < j && sym < shift_symbol[j - 1]; j--)

        shift_symbol[j] = shift_symbol[j - 1];
       shift_symbol[j] = sym;
     }
        shift_symbol[j] = shift_symbol[j - 1];
       shift_symbol[j] = sym;
     }


@@ -274,14 +270,23 @@ static void
 save_reductions (state *s)
 {
   int count = 0;
 save_reductions (state *s)
 {
   int count = 0;

-  int i;
+  size_t i;

 
   /* Find and count the active items that represent ends of rules. */
 
   /* Find and count the active items that represent ends of rules. */

-  for (i = 0; i < nritemset; ++i)
+  for (i = 0; i < nitemset; ++i)

     {
     {

-      int item = ritem[itemset[i]];
-      if (item < 0)
-       redset[count++] = &rules[item_number_as_rule_number (item)];
+      item_number item = ritem[itemset[i]];
+      if (item_number_is_rule_number (item))
+       {
+         rule_number r = item_number_as_rule_number (item);
+         redset[count++] = &rules[r];
+         if (r == 0)
+           {
+             /* This is "reduce 0", i.e., accept. */
+             aver (!final_state);
+             final_state = s;
+           }
+       }

     }
 
   /* Make a reductions structure and copy the data into it.  */
     }
 
   /* Make a reductions structure and copy the data into it.  */


@@ -296,7 +301,7 @@ save_reductions (state *s)
 static void
 set_states (void)
 {
 static void
 set_states (void)
 {

-  CALLOC (states, nstates);
+  states = xcalloc (nstates, sizeof *states);

 
   while (first_state)
     {
 
   while (first_state)
     {


@@ -323,36 +328,32 @@ set_states (void)
 
 
 /*-------------------------------------------------------------------.
 
 
 /*-------------------------------------------------------------------.

-| Compute the nondeterministic finite state machine (see state.h for |
-| details) from the grammar.                                         |
+| Compute the LR(0) parser states (see state.h for details) from the |
+| grammar.                                                           |

 `-------------------------------------------------------------------*/
 
 void
 generate_states (void)
 {
 `-------------------------------------------------------------------*/
 
 void
 generate_states (void)
 {

+  item_number initial_core = 0;

   state_list *list = NULL;
   allocate_storage ();
   new_closure (nritems);
 
   /* Create the initial state.  The 0 at the lhs is the index of the
      item of this initial rule.  */
   state_list *list = NULL;
   allocate_storage ();
   new_closure (nritems);
 
   /* Create the initial state.  The 0 at the lhs is the index of the
      item of this initial rule.  */

-  kernel_base[0][0] = 0;
-  kernel_size[0] = 1;
-  state_list_append (0, kernel_size[0], kernel_base[0]);
+  state_list_append (0, 1, &initial_core);

 
 

-  list = first_state;
-
-  while (list)
+  /* States are queued when they are created; process them all.  */
+  for (list = first_state; list; list = list->next)

     {
       state *s = list->state;
       if (trace_flag & trace_automaton)
        fprintf (stderr, "Processing state %d (reached by %s)\n",
                 s->number,
                 symbols[s->accessing_symbol]->tag);
     {
       state *s = list->state;
       if (trace_flag & trace_automaton)
        fprintf (stderr, "Processing state %d (reached by %s)\n",
                 s->number,
                 symbols[s->accessing_symbol]->tag);

-      /* Set up ruleset and itemset for the transitions out of this
-         state.  ruleset gets a 1 bit for each rule that could reduce
-         now.  itemset gets a vector of all the items that could be
-         accepted next.  */
+      /* Set up itemset for the transitions out of this state.  itemset gets a
+         vector of all the items that could be accepted next.  */

       closure (s->items, s->nitems);
       /* Record the reductions allowed out of this state.  */
       save_reductions (s);
       closure (s->items, s->nitems);
       /* Record the reductions allowed out of this state.  */
       save_reductions (s);


@@ -364,10 +365,6 @@ generate_states (void)
       /* Create the shifts structures for the shifts to those states,
         now that the state numbers transitioning to are known.  */
       state_transitions_set (s, nshifts, shiftset);
       /* Create the shifts structures for the shifts to those states,
         now that the state numbers transitioning to are known.  */
       state_transitions_set (s, nshifts, shiftset);

-
-      /* states are queued when they are created; process them all.
-        */
-      list = list->next;

     }
 
   /* discard various storage */
     }
 
   /* discard various storage */