gnulib: update.

[bison.git] / src / state.c

diff --git a/src/state.c b/src/state.c
index 773071267335a3b1b319af60acf5194617f9bf70..666e0cc7a246219e264a57c22978479d1004d148 100644 (file)
--- a/src/state.c
+++ b/src/state.c
@@ -1,29 +1,31 @@
-/* Type definitions for nondeterministic finite state machine for bison,
-   Copyright (C) 2001, 2002  Free Software Foundation, Inc.
+/* Type definitions for the finite state machine for Bison.
+
+   Copyright (C) 2001-2007, 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/>.  */

 
 

+#include <config.h>

 #include "system.h"
 #include "system.h"

-#include "hash.h"
+
+#include <hash.h>
+

 #include "complain.h"
 #include "gram.h"
 #include "state.h"
 #include "complain.h"
 #include "gram.h"
 #include "state.h"

+#include "print-xml.h"

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


@@ -31,37 +33,36 @@
                        `-------------------*/
 
 
                        `-------------------*/
 
 

-/*---------------------------------------.
-| Create a new array of N shifts/gotos.  |
-`---------------------------------------*/
+/*-----------------------------------------.
+| Create a new array of NUM shifts/gotos.  |
+`-----------------------------------------*/

 
 

-#define TRANSITIONS_ALLOC(Num)                                         \
-  (transitions_t *) xcalloc ((sizeof (transitions_t)                   \
-                                  + (Num - 1) * sizeof (state_t *)), 1)
-
-static transitions_t *
-transitions_new (int num, state_t **the_states)
+static transitions *
+transitions_new (int num, state **the_states)

 {
 {

-  transitions_t *res = TRANSITIONS_ALLOC (num);
+  size_t states_size = num * sizeof *the_states;
+  transitions *res = xmalloc (offsetof (transitions, states) + states_size);

   res->num = num;
   res->num = num;

-  memcpy (res->states, the_states, num * sizeof (the_states[0]));
+  memcpy (res->states, the_states, states_size);

   return res;
 }
 
 
   return res;
 }
 
 

-/*-------------------------------------------------------------------.
-| Return the state such these TRANSITIONS contain a shift/goto to it |
-| on SYMBOL.  Aborts if none found.                                  |
-`-------------------------------------------------------------------*/
+/*-------------------------------------------------------.
+| Return the state such that SHIFTS contain a shift/goto |
+| to it on SYM.  Abort if none found.                    |
+`-------------------------------------------------------*/

 
 

-state_t *
-transitions_to (transitions_t *shifts, symbol_number_t s)
+state *
+transitions_to (transitions *shifts, symbol_number sym)

 {
   int j;
 {
   int j;

-  for (j = 0; j < shifts->num; j++)
-    if (TRANSITION_SYMBOL (shifts, j) == s)
-      return shifts->states[j];
-  abort ();
+  for (j = 0; ; j++)
+    {
+      aver (j < shifts->num);
+      if (TRANSITION_SYMBOL (shifts, j) == sym)
+       return shifts->states[j];
+    }

 }
 
 
 }
 
 


@@ -70,21 +71,17 @@ transitions_to (transitions_t *shifts, symbol_number_t s)
                        `--------------------*/
 
 
                        `--------------------*/
 
 

-/*-------------------------------.
-| Create a new array of N errs.  |
-`-------------------------------*/
-
-#define ERRS_ALLOC(Nerrs)                              \
-  (errs_t *) xcalloc ((sizeof (errs_t)                 \
-                      + (Nerrs - 1) * sizeof (symbol_t *)), 1)
-
+/*---------------------------------.
+| Create a new array of NUM errs.  |
+`---------------------------------*/

 
 

-errs_t *
-errs_new (int num, symbol_t **tokens)
+errs *
+errs_new (int num, symbol **tokens)

 {
 {

-  errs_t *res = ERRS_ALLOC (num);
+  size_t symbols_size = num * sizeof *tokens;
+  errs *res = xmalloc (offsetof (errs, symbols) + symbols_size);

   res->num = num;
   res->num = num;

-  memcpy (res->symbols, tokens, num * sizeof (tokens[0]));
+  memcpy (res->symbols, tokens, symbols_size);

   return res;
 }
 
   return res;
 }
 


@@ -96,20 +93,18 @@ errs_new (int num, symbol_t **tokens)
                        `-------------*/
 
 
                        `-------------*/
 
 

-/*-------------------------------------.
-| Create a new array of N reductions.  |
-`-------------------------------------*/
-
-#define REDUCTIONS_ALLOC(Nreductions)                          \
-  (reductions_t *) xcalloc ((sizeof (reductions_t)             \
-                            + (Nreductions - 1) * sizeof (rule_t *)), 1)
+/*---------------------------------------.
+| Create a new array of NUM reductions.  |
+`---------------------------------------*/

 
 

-static reductions_t *
-reductions_new (int num, rule_t **reductions)
+static reductions *
+reductions_new (int num, rule **reds)

 {
 {

-  reductions_t *res = REDUCTIONS_ALLOC (num);
+  size_t rules_size = num * sizeof *reds;
+  reductions *res = xmalloc (offsetof (reductions, rules) + rules_size);

   res->num = num;
   res->num = num;

-  memcpy (res->rules, reductions, num * sizeof (reductions[0]));
+  res->lookahead_tokens = NULL;
+  memcpy (res->rules, reds, rules_size);

   return res;
 }
 
   return res;
 }
 


@@ -120,130 +115,190 @@ reductions_new (int num, rule_t **reductions)
                        `---------*/
 
 
                        `---------*/
 
 

-state_number_t nstates = 0;
+state_number nstates = 0;

 /* FINAL_STATE is properly set by new_state when it recognizes its
    accessing symbol: $end.  */
 /* FINAL_STATE is properly set by new_state when it recognizes its
    accessing symbol: $end.  */

-state_t *final_state = NULL;
+state *final_state = NULL;

 
 

-#define STATE_ALLOC(Nitems)                                            \
-  (state_t *) xcalloc ((sizeof (state_t)                               \
-                       + (Nitems - 1) * sizeof (item_number_t)), 1)

 
 /*------------------------------------------------------------------.
 | Create a new state with ACCESSING_SYMBOL, for those items.  Store |
 | it in the state hash table.                                       |
 `------------------------------------------------------------------*/
 
 
 /*------------------------------------------------------------------.
 | Create a new state with ACCESSING_SYMBOL, for those items.  Store |
 | it in the state hash table.                                       |
 `------------------------------------------------------------------*/
 

-state_t *
-state_new (symbol_number_t accessing_symbol,
-          size_t core_size, item_number_t *core)
+state *
+state_new (symbol_number accessing_symbol,
+          size_t nitems, item_number *core)

 {
 {

-  state_t *res;
+  state *res;
+  size_t items_size = nitems * sizeof *core;

 
 

-  if (nstates >= STATE_NUMBER_MAX)
-    fatal (_("too many states (max %d)"), STATE_NUMBER_MAX);
+  aver (nstates < STATE_NUMBER_MAXIMUM);

 
 

-  res = STATE_ALLOC (core_size);
+  res = xmalloc (offsetof (state, items) + items_size);
+  res->number = nstates++;

   res->accessing_symbol = accessing_symbol;
   res->accessing_symbol = accessing_symbol;

-  res->number = nstates;
-  ++nstates;
+  res->transitions = NULL;
+  res->reductions = NULL;
+  res->errs = NULL;
+  res->state_list = NULL;
+  res->consistent = 0;

   res->solved_conflicts = NULL;
   res->solved_conflicts = NULL;

+  res->solved_conflicts_xml = NULL;

 
 

-  res->nitems = core_size;
-  memcpy (res->items, core, core_size * sizeof (core[0]));
+  res->nitems = nitems;
+  memcpy (res->items, core, items_size);

 
   state_hash_insert (res);
 
   return res;
 }
 
 
   state_hash_insert (res);
 
   return res;
 }
 

+state *
+state_new_isocore (state const *s)
+{
+  state *res;
+  size_t items_size = s->nitems * sizeof *s->items;
+
+  aver (nstates < STATE_NUMBER_MAXIMUM);
+
+  res = xmalloc (offsetof (state, items) + items_size);
+  res->number = nstates++;
+  res->accessing_symbol = s->accessing_symbol;
+  res->transitions =
+    transitions_new (s->transitions->num, s->transitions->states);
+  res->reductions = reductions_new (s->reductions->num, s->reductions->rules);
+  res->errs = NULL;
+  res->state_list = NULL;
+  res->consistent = s->consistent;
+  res->solved_conflicts = NULL;
+  res->solved_conflicts_xml = NULL;
+
+  res->nitems = s->nitems;
+  memcpy (res->items, s->items, items_size);
+
+  return res;
+}

 
 

-/*-------------.
-| Free STATE.  |
-`-------------*/
+
+/*---------.
+| Free S.  |
+`---------*/

 
 static void
 
 static void

-state_free (state_t *state)
+state_free (state *s)

 {
 {

-  free (state->transitions);
-  free (state->reductions);
-  free (state->errs);
-  free (state);
+  free (s->transitions);
+  free (s->reductions);
+  free (s->errs);
+  free (s);

 }
 
 
 }
 
 

-/*-------------------------------.
-| Set the transitions of STATE.  |
-`-------------------------------*/
+/*---------------------------.
+| Set the transitions of S.  |
+`---------------------------*/

 
 void
 
 void

-state_transitions_set (state_t *state, int num, state_t **transitions)
+state_transitions_set (state *s, int num, state **trans)

 {
 {

-  assert (!state->transitions);
-  state->transitions = transitions_new (num, transitions);
+  aver (!s->transitions);
+  s->transitions = transitions_new (num, trans);

 }
 
 
 }
 
 

-/*------------------------------.
-| Set the reductions of STATE.  |
-`------------------------------*/
+/*--------------------------.
+| Set the reductions of S.  |
+`--------------------------*/

 
 void
 
 void

-state_reductions_set (state_t *state, int num, rule_t **reductions)
+state_reductions_set (state *s, int num, rule **reds)

 {
 {

-  assert (!state->reductions);
-  state->reductions = reductions_new (num, reductions);
+  aver (!s->reductions);
+  s->reductions = reductions_new (num, reds);

 }
 
 
 }
 
 

-/*------------------------.
-| Set the errs of STATE.  |
-`------------------------*/
+int
+state_reduction_find (state *s, rule *r)
+{
+  int i;
+  reductions *reds = s->reductions;
+  for (i = 0; i < reds->num; ++i)
+    if (reds->rules[i] == r)
+      return i;
+  return -1;
+}
+
+
+/*--------------------.
+| Set the errs of S.  |
+`--------------------*/

 
 void
 
 void

-state_errs_set (state_t *state, int num, symbol_t **tokens)
+state_errs_set (state *s, int num, symbol **tokens)

 {
 {

-  assert (!state->errs);
-  state->errs = errs_new (num, tokens);
+  aver (!s->errs);
+  s->errs = errs_new (num, tokens);

 }
 
 
 
 }
 
 
 

-/*--------------------------------------------------------------.
-| Print on OUT all the lookaheads such that this STATE wants to |
-| reduce this RULE.                                             |
-`--------------------------------------------------------------*/
+/*--------------------------------------------------.
+| Print on OUT all the lookahead tokens such that S |
+| wants to reduce R.                                |
+`--------------------------------------------------*/

 
 void
 
 void

-state_rule_lookaheads_print (state_t *state, rule_t *rule, FILE *out)
+state_rule_lookahead_tokens_print (state *s, rule *r, FILE *out)

 {
 {

-  int j, k;
-  bitset_iterator biter;
-  int nlookaheads = 0;
-  /* Count the number of lookaheads corresponding to this rule.  */
-  for (j = 0; j < state->nlookaheads; ++j)
-    BITSET_FOR_EACH (biter, state->lookaheads[j], k, 0)
-      if (state->lookaheads_rule[j]->number == rule->number)
-       nlookaheads++;
+  /* Find the reduction we are handling.  */
+  reductions *reds = s->reductions;
+  int red = state_reduction_find (s, r);

 
   /* Print them if there are.  */
 
   /* Print them if there are.  */

-  if (nlookaheads)
+  if (reds->lookahead_tokens && red != -1)

     {
     {

+      bitset_iterator biter;
+      int k;
+      char const *sep = "";

       fprintf (out, "  [");
       fprintf (out, "  [");

-      for (j = 0; j < state->nlookaheads; ++j)
-       BITSET_FOR_EACH (biter, state->lookaheads[j], k, 0)
-         if (state->lookaheads_rule[j]->number == rule->number)
-           fprintf (out, "%s%s",
-                    symbols[k]->tag,
-                    --nlookaheads ? ", " : "");
+      BITSET_FOR_EACH (biter, reds->lookahead_tokens[red], k, 0)
+       {
+         fprintf (out, "%s%s", sep, symbols[k]->tag);
+         sep = ", ";
+       }

       fprintf (out, "]");
     }
 }
 
       fprintf (out, "]");
     }
 }
 

+void
+state_rule_lookahead_tokens_print_xml (state *s, rule *r,
+                                      FILE *out, int level)
+{
+  /* Find the reduction we are handling.  */
+  reductions *reds = s->reductions;
+  int red = state_reduction_find (s, r);
+
+  /* Print them if there are.  */
+  if (reds->lookahead_tokens && red != -1)
+    {
+      bitset_iterator biter;
+      int k;
+      xml_puts (out, level, "<lookaheads>");
+      BITSET_FOR_EACH (biter, reds->lookahead_tokens[red], k, 0)
+       {
+         xml_printf (out, level + 1, "<symbol>%s</symbol>",
+                     xml_escape (symbols[k]->tag));
+       }
+      xml_puts (out, level, "</lookaheads>");
+    }
+}
+

 
 

-/*----------------------.
+/*---------------------.

 | A state hash table.  |
 | A state hash table.  |

-`----------------------*/
+`---------------------*/

 
 /* Initial capacity of states hash table.  */
 #define HT_INITIAL_CAPACITY 257
 
 /* Initial capacity of states hash table.  */
 #define HT_INITIAL_CAPACITY 257


@@ -251,32 +306,44 @@ state_rule_lookaheads_print (state_t *state, rule_t *rule, FILE *out)
 static struct hash_table *state_table = NULL;
 
 /* Two states are equal if they have the same core items.  */
 static struct hash_table *state_table = NULL;
 
 /* Two states are equal if they have the same core items.  */

-static bool
-state_compare (const state_t *s1, const state_t *s2)
+static inline bool
+state_compare (state const *s1, state const *s2)

 {
 {

-  int i;
+  size_t i;

 
   if (s1->nitems != s2->nitems)
 
   if (s1->nitems != s2->nitems)

-    return FALSE;
+    return false;

 
   for (i = 0; i < s1->nitems; ++i)
     if (s1->items[i] != s2->items[i])
 
   for (i = 0; i < s1->nitems; ++i)
     if (s1->items[i] != s2->items[i])

-      return FALSE;
+      return false;
+
+  return true;
+}

 
 

-  return TRUE;
+static bool
+state_comparator (void const *s1, void const *s2)
+{
+  return state_compare (s1, s2);

 }
 
 }
 

-static unsigned int
-state_hash (const state_t *state, unsigned int tablesize)
+static inline size_t
+state_hash (state const *s, size_t tablesize)

 {
   /* Add up the state's item numbers to get a hash key.  */
 {
   /* Add up the state's item numbers to get a hash key.  */

-  int key = 0;
-  int i;
-  for (i = 0; i < state->nitems; ++i)
-    key += state->items[i];
+  size_t key = 0;
+  size_t i;
+  for (i = 0; i < s->nitems; ++i)
+    key += s->items[i];

   return key % tablesize;
 }
 
   return key % tablesize;
 }
 

+static size_t
+state_hasher (void const *s, size_t tablesize)
+{
+  return state_hash (s, tablesize);
+}
+

 
 /*-------------------------------.
 | Create the states hash table.  |
 
 /*-------------------------------.
 | Create the states hash table.  |


@@ -287,9 +354,9 @@ state_hash_new (void)
 {
   state_table = hash_initialize (HT_INITIAL_CAPACITY,
                                 NULL,
 {
   state_table = hash_initialize (HT_INITIAL_CAPACITY,
                                 NULL,

-                                (Hash_hasher) state_hash,
-                                (Hash_comparator) state_compare,
-                                (Hash_data_freer) NULL);
+                                state_hasher,
+                                state_comparator,
+                                NULL);

 }
 
 
 }
 
 


@@ -304,14 +371,15 @@ state_hash_free (void)
 }
 
 
 }
 
 

-/*---------------------------------------.
-| Insert STATE in the state hash table.  |
-`---------------------------------------*/
+/*-----------------------------------.
+| Insert S in the state hash table.  |
+`-----------------------------------*/

 
 void
 
 void

-state_hash_insert (state_t *state)
+state_hash_insert (state *s)

 {
 {

-  hash_insert (state_table, state);
+  if (!hash_insert (state_table, s))
+    xalloc_die ();

 }
 
 
 }
 
 


@@ -320,21 +388,68 @@ state_hash_insert (state_t *state)
 | not exist yet, return NULL.                                       |
 `------------------------------------------------------------------*/
 
 | not exist yet, return NULL.                                       |
 `------------------------------------------------------------------*/
 

-state_t *
-state_hash_lookup (size_t core_size, item_number_t *core)
+state *
+state_hash_lookup (size_t nitems, item_number *core)

 {
 {

-  state_t *probe = STATE_ALLOC (core_size);
-  state_t *entry;
+  size_t items_size = nitems * sizeof *core;
+  state *probe = xmalloc (offsetof (state, items) + items_size);
+  state *entry;

 
 

-  probe->nitems = core_size;
-  memcpy (probe->items, core, core_size * sizeof (core[0]));
+  probe->nitems = nitems;
+  memcpy (probe->items, core, items_size);

   entry = hash_lookup (state_table, probe);
   free (probe);
   return entry;
 }
 
   entry = hash_lookup (state_table, probe);
   free (probe);
   return entry;
 }
 

+
+/*--------------------------------------------------------.
+| Record S and all states reachable from S in REACHABLE.  |
+`--------------------------------------------------------*/
+
+static void
+state_record_reachable_states (state *s, bitset reachable)
+{
+  if (bitset_test (reachable, s->number))
+    return;
+  bitset_set (reachable, s->number);
+  {
+    int i;
+    for (i = 0; i < s->transitions->num; ++i)
+      if (!TRANSITION_IS_DISABLED (s->transitions, i))
+        state_record_reachable_states (s->transitions->states[i], reachable);
+  }
+}
+
+void
+state_remove_unreachable_states (state_number old_to_new[])
+{
+  state_number nstates_reachable = 0;
+  bitset reachable = bitset_create (nstates, BITSET_FIXED);
+  state_record_reachable_states (states[0], reachable);
+  {
+    state_number i;
+    for (i = 0; i < nstates; ++i)
+      {
+        if (bitset_test (reachable, states[i]->number))
+          {
+            states[nstates_reachable] = states[i];
+            states[nstates_reachable]->number = nstates_reachable;
+            old_to_new[i] = nstates_reachable++;
+          }
+        else
+          {
+            state_free (states[i]);
+            old_to_new[i] = nstates;
+          }
+      }
+  }
+  nstates = nstates_reachable;
+  bitset_free (reachable);
+}
+

 /* All the decorated states, indexed by the state number.  */
 /* All the decorated states, indexed by the state number.  */

-state_t **states = NULL;
+state **states = NULL;

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


@@ -344,7 +459,7 @@ state_t **states = NULL;
 void
 states_free (void)
 {
 void
 states_free (void)
 {

-  state_number_t i;
+  state_number i;

   for (i = 0; i < nstates; ++i)
     state_free (states[i]);
   free (states);
   for (i = 0; i < nstates; ++i)
     state_free (states[i]);
   free (states);