2007-02-07 Paolo Bonzini <bonzini@gnu.org>

[bison.git] / src / state.c

diff --git a/src/state.c b/src/state.c
index 8148702e57e05ce1446dc2edf0805c18dae45321..280a2f4134654241fc29e18ca5aedf3c0d64310a 100644 (file)
--- a/src/state.c
+++ b/src/state.c
@@ -1,5 +1,7 @@
-/* Type definitions for nondeterministic finite state machine for bison,
-   Copyright (C) 2001, 2002  Free Software Foundation, Inc.
+/* Type definitions for nondeterministic finite state machine for Bison.
+
+   Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006 Free Software
+   Foundation, Inc.

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


@@ -15,12 +17,14 @@
 
    You should have received a copy of the GNU General Public License
    along with Bison; see the file COPYING.  If not, write to
 
    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.  */
-
+   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301, USA.  */

 
 

+#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"


@@ -31,24 +35,37 @@
                        `-------------------*/
 
 
                        `-------------------*/
 
 

-/*---------------------------------------.
-| Create a new array of N shifts/gotos.  |
-`---------------------------------------*/
-
-#define SHIFTS_ALLOC(Nshifts)                                          \
-  (shifts_t *) xcalloc ((unsigned) (sizeof (shifts_t)                  \
-                                  + (Nshifts - 1) * sizeof (state_number_t)), 1)
+/*-----------------------------------------.
+| Create a new array of NUM shifts/gotos.  |
+`-----------------------------------------*/

 
 

-static shifts_t *
-shifts_new (int nshifts, state_number_t *shifts)
+static transitions *
+transitions_new (int num, state **the_states)

 {
 {

-  shifts_t *res = SHIFTS_ALLOC (nshifts);
-  res->nshifts = nshifts;
-  memcpy (res->shifts, shifts, nshifts * sizeof (shifts[0]));
+  size_t states_size = num * sizeof *the_states;
+  transitions *res = xmalloc (offsetof (transitions, states) + states_size);
+  res->num = num;
+  memcpy (res->states, the_states, states_size);

   return res;
 }
 
 
   return res;
 }
 
 

+/*-------------------------------------------------------.
+| Return the state such that SHIFTS contain a shift/goto |
+| to it on SYM.  Abort if none found.                    |
+`-------------------------------------------------------*/
+
+state *
+transitions_to (transitions *shifts, symbol_number sym)
+{
+  int j;
+  for (j = 0; ; j++)
+    {
+      aver (j < shifts->num);
+      if (TRANSITION_SYMBOL (shifts, j) == sym)
+       return shifts->states[j];
+    }
+}

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


@@ -56,29 +73,17 @@ shifts_new (int nshifts, state_number_t *shifts)
                        `--------------------*/
 
 
                        `--------------------*/
 
 

-/*-------------------------------.
-| Create a new array of N errs.  |
-`-------------------------------*/
-
-#define ERRS_ALLOC(Nerrs)                                              \
-  (errs *) xcalloc ((unsigned) (sizeof (errs)                          \
-                                  + (Nerrs - 1) * sizeof (short)), 1)
-
-
-errs *
-errs_new (int n)
-{
-  errs *res = ERRS_ALLOC (n);
-  res->nerrs = n;
-  return res;
-}
-
+/*---------------------------------.
+| Create a new array of NUM errs.  |
+`---------------------------------*/

 
 errs *
 
 errs *

-errs_dup (errs *src)
+errs_new (int num, symbol **tokens)

 {
 {

-  errs *res = errs_new (src->nerrs);
-  memcpy (res->errs, src->errs, src->nerrs * sizeof (src->errs[0]));
+  size_t symbols_size = num * sizeof *tokens;
+  errs *res = xmalloc (offsetof (errs, symbols) + symbols_size);
+  res->num = num;
+  memcpy (res->symbols, tokens, symbols_size);

   return res;
 }
 
   return res;
 }
 


@@ -90,19 +95,18 @@ errs_dup (errs *src)
                        `-------------*/
 
 
                        `-------------*/
 
 

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

 
 

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

 {
 {

-  reductions *res = REDUCTIONS_ALLOC (n);
-  res->nreds = n;
+  size_t rules_size = num * sizeof *reds;
+  reductions *res = xmalloc (offsetof (reductions, rules) + rules_size);
+  res->num = num;
+  res->lookahead_tokens = NULL;
+  memcpy (res->rules, reds, rules_size);

   return res;
 }
 
   return res;
 }
 


@@ -113,89 +117,139 @@ reductions_new (int n)
                        `---------*/
 
 
                        `---------*/
 
 

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

 /* FINAL_STATE is properly set by new_state when it recognizes its
 /* FINAL_STATE is properly set by new_state when it recognizes its

-   accessing symbol: EOF.  */
-state_t *final_state = NULL;
+   accessing symbol: $end.  */
+state *final_state = NULL;

 
 

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

 
 

-/*------------------------------------------------------------.
-| Create a new state with ACCESSING_SYMBOL, for those items.  |
-`------------------------------------------------------------*/
+/*------------------------------------------------------------------.
+| 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->consistent = 0;

   res->solved_conflicts = NULL;
 
   res->solved_conflicts = 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;
 }
 
 
 
   return res;
 }
 
 

+/*---------.
+| Free S.  |
+`---------*/
+
+static void
+state_free (state *s)
+{
+  free (s->transitions);
+  free (s->reductions);
+  free (s->errs);
+  free (s);
+}
+
+
+/*---------------------------.
+| Set the transitions of S.  |
+`---------------------------*/
+
+void
+state_transitions_set (state *s, int num, state **trans)
+{
+  aver (!s->transitions);
+  s->transitions = transitions_new (num, trans);
+}
+
+

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

-| Set the shifts of STATE.  |
+| Set the reductions of S.  |

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

-state_shifts_set (state_t *state, int nshifts, state_number_t *shifts)
+state_reductions_set (state *s, int num, rule **reds)

 {
 {

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

 }
 
 
 }
 
 

+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;
+}
+

 
 

-/*--------------------------------------------------------------.
-| Print on OUT all the lookaheads such that this STATE wants to |
-| reduce this RULE.                                             |
-`--------------------------------------------------------------*/
+/*--------------------.
+| Set the errs of S.  |
+`--------------------*/

 
 void
 
 void

-state_rule_lookaheads_print (state_t *state, rule_t *rule, FILE *out)
+state_errs_set (state *s, int num, symbol **tokens)

 {
 {

-  int j, k;
-  int nlookaheads = 0;
-  /* Count the number of lookaheads corresponding to this rule.  */
-  for (j = 0; j < state->nlookaheads; ++j)
-    for (k = 0; k < ntokens; ++k)
-      if (bitset_test (state->lookaheads[j], k)
-         && state->lookaheads_rule[j]->number == rule->number)
-       nlookaheads++;
+  aver (!s->errs);
+  s->errs = errs_new (num, tokens);
+}
+
+
+
+/*--------------------------------------------------.
+| Print on OUT all the lookahead tokens such that S |
+| wants to reduce R.                                |
+`--------------------------------------------------*/
+
+void
+state_rule_lookahead_tokens_print (state *s, rule *r, FILE *out)
+{
+  /* 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)
-       for (k = 0; k < ntokens; ++k)
-         if (bitset_test (state->lookaheads[j], k)
-             && state->lookaheads_rule[j]->number == rule->number)
-           fprintf (out, "%s%s",
-                    symbol_tag_get (symbols[k]),
-                    --nlookaheads ? ", " : "");
+      BITSET_FOR_EACH (biter, reds->lookahead_tokens[red], k, 0)
+       {
+         fprintf (out, "%s%s", sep, symbols[k]->tag);
+         sep = ", ";
+       }

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

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

 | 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


@@ -203,32 +257,44 @@ 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.  |


@@ -239,9 +305,9 @@ 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);

 }
 
 
 }
 
 


@@ -256,14 +322,14 @@ 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);
+  hash_insert (state_table, s);

 }
 
 
 }
 
 


@@ -272,21 +338,22 @@ 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;
 }
 
 /* All the decorated states, indexed by the state number.  */
   entry = hash_lookup (state_table, probe);
   free (probe);
   return entry;
 }
 
 /* All the decorated states, indexed by the state number.  */

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

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


@@ -296,14 +363,8 @@ 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)
   for (i = 0; i < nstates; ++i)

-    {
-      free (states[i]->shifts);
-      XFREE (states[i]->reductions);
-      free (states[i]->errs);
-      free (states[i]);
-    }
-  XFREE (states);
+    state_free (states[i]);
+  free (states);

 }
 }