* doc/bison.texinfo (Stack Overflow): xref to Recursion.

[bison.git] / src / state.c

diff --git a/src/state.c b/src/state.c
index a23199e310951c04646fe6efd0954518f266c294..71914025c96ac2112921bad287f0d5cde056c2b8 100644 (file)
--- a/src/state.c
+++ b/src/state.c
@@ -35,12 +35,12 @@
 | Create a new array of N shifts/gotos.  |
 `---------------------------------------*/
 
 | Create a new array of N shifts/gotos.  |
 `---------------------------------------*/
 

-#define TRANSITIONS_ALLOC(Nshifts)                                             \
-  (transitions_t *) xcalloc ((unsigned) (sizeof (transitions_t)                        \
-                                  + (Nshifts - 1) * sizeof (state_number_t)), 1)
+#define TRANSITIONS_ALLOC(Num)                                         \
+  (transitions_t *) xcalloc ((sizeof (transitions_t)                   \
+                                  + (Num - 1) * sizeof (state_t *)), 1)

 
 static transitions_t *
 
 static transitions_t *

-transitions_new (int num, state_number_t *the_states)
+transitions_new (int num, state_t **the_states)

 {
   transitions_t *res = TRANSITIONS_ALLOC (num);
   res->num = num;
 {
   transitions_t *res = TRANSITIONS_ALLOC (num);
   res->num = num;


@@ -60,7 +60,7 @@ transitions_to (transitions_t *shifts, symbol_number_t s)
   int j;
   for (j = 0; j < shifts->num; j++)
     if (TRANSITION_SYMBOL (shifts, j) == s)
   int j;
   for (j = 0; j < shifts->num; j++)
     if (TRANSITION_SYMBOL (shifts, j) == s)

-      return states[shifts->states[j]];
+      return shifts->states[j];

   abort ();
 }
 
   abort ();
 }
 


@@ -74,25 +74,17 @@ transitions_to (transitions_t *shifts, symbol_number_t s)
 | Create a new array of N errs.  |
 `-------------------------------*/
 
 | Create a new array of N errs.  |
 `-------------------------------*/
 

-#define ERRS_ALLOC(Nerrs)                                              \
-  (errs_t *) xcalloc ((unsigned) (sizeof (errs_t)                      \
-                                  + (Nerrs - 1) * sizeof (short)), 1)
+#define ERRS_ALLOC(Nerrs)                              \
+  (errs_t *) xcalloc ((sizeof (errs_t)                 \
+                      + (Nerrs - 1) * sizeof (symbol_t *)), 1)

 
 
 errs_t *
 
 
 errs_t *

-errs_new (int n)
+errs_new (int num, symbol_t **tokens)

 {
 {

-  errs_t *res = ERRS_ALLOC (n);
-  res->nerrs = n;
-  return res;
-}
-
-
-errs_t *
-errs_dup (errs_t *src)
-{
-  errs_t *res = errs_new (src->nerrs);
-  memcpy (res->errs, src->errs, src->nerrs * sizeof (src->errs[0]));
+  errs_t *res = ERRS_ALLOC (num);
+  res->num = num;
+  memcpy (res->symbols, tokens, num * sizeof (tokens[0]));

   return res;
 }
 
   return res;
 }
 


@@ -108,16 +100,17 @@ errs_dup (errs_t *src)
 | Create a new array of N reductions.  |
 `-------------------------------------*/
 
 | Create a new array of N reductions.  |
 `-------------------------------------*/
 

-#define REDUCTIONS_ALLOC(Nreductions)                                  \
-  (reductions_t *) xcalloc ((unsigned) (sizeof (reductions_t)          \
-                                  + (Nreductions - 1) * sizeof (short)), 1)
+#define REDUCTIONS_ALLOC(Nreductions)                          \
+  (reductions_t *) xcalloc ((sizeof (reductions_t)             \
+                            + (Nreductions - 1) * sizeof (rule_t *)), 1)

 
 static reductions_t *
 
 static reductions_t *

-reductions_new (int nreductions, short *reductions)
+reductions_new (int num, rule_t **reductions)

 {
 {

-  reductions_t *res = REDUCTIONS_ALLOC (nreductions);
-  res->nreds = nreductions;
-  memcpy (res->rules, reductions, nreductions * sizeof (reductions[0]));
+  reductions_t *res = REDUCTIONS_ALLOC (num);
+  res->num = num;
+  memcpy (res->rules, reductions, num * sizeof (reductions[0]));
+  res->lookaheads = NULL;

   return res;
 }
 
   return res;
 }
 


@@ -130,16 +123,17 @@ reductions_new (int nreductions, short *reductions)
 
 state_number_t nstates = 0;
 /* FINAL_STATE is properly set by new_state when it recognizes its
 
 state_number_t nstates = 0;
 /* FINAL_STATE is properly set by new_state when it recognizes its

-   accessing symbol: EOF.  */
+   accessing symbol: $end.  */

 state_t *final_state = NULL;
 
 #define STATE_ALLOC(Nitems)                                            \
 state_t *final_state = NULL;
 
 #define STATE_ALLOC(Nitems)                                            \

-  (state_t *) xcalloc ((unsigned) (sizeof (state_t)                    \
-                                  + (Nitems - 1) * sizeof (item_number_t)), 1)
+  (state_t *) xcalloc ((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,
 
 state_t *
 state_new (symbol_number_t accessing_symbol,


@@ -159,18 +153,35 @@ state_new (symbol_number_t accessing_symbol,
   res->nitems = core_size;
   memcpy (res->items, core, core_size * sizeof (core[0]));
 
   res->nitems = core_size;
   memcpy (res->items, core, core_size * sizeof (core[0]));
 

+  state_hash_insert (res);
+

   return res;
 }
 
 
   return res;
 }
 
 

-/*--------------------------.
-| Set the shifts of STATE.  |
-`--------------------------*/
+/*-------------.
+| Free STATE.  |
+`-------------*/
+
+static void
+state_free (state_t *state)
+{
+  free (state->transitions);
+  free (state->reductions);
+  free (state->errs);
+  free (state);
+}
+
+
+/*-------------------------------.
+| Set the transitions of STATE.  |
+`-------------------------------*/

 
 void
 
 void

-state_transitions_set (state_t *state, int nshifts, state_number_t *shifts)
+state_transitions_set (state_t *state, int num, state_t **transitions)

 {
 {

-  state->shifts = transitions_new (nshifts, shifts);
+  assert (!state->transitions);
+  state->transitions = transitions_new (num, transitions);

 }
 
 
 }
 
 


@@ -179,9 +190,34 @@ state_transitions_set (state_t *state, int nshifts, state_number_t *shifts)
 `------------------------------*/
 
 void
 `------------------------------*/
 
 void

-state_reductions_set (state_t *state, int nreductions, short *reductions)
+state_reductions_set (state_t *state, int num, rule_t **reductions)
+{
+  assert (!state->reductions);
+  state->reductions = reductions_new (num, reductions);
+}
+
+
+int
+state_reduction_find (state_t *state, rule_t *rule)
+{
+  int i;
+  reductions_t *reds = state->reductions;
+  for (i = 0; i < reds->num; ++i)
+    if (reds->rules[i] == rule)
+      return i;
+  return -1;
+}
+
+
+/*------------------------.
+| Set the errs of STATE.  |
+`------------------------*/
+
+void
+state_errs_set (state_t *state, int num, symbol_t **tokens)

 {
 {

-  state->reductions = reductions_new (nreductions, reductions);
+  assert (!state->errs);
+  state->errs = errs_new (num, tokens);

 }
 
 
 }
 
 


@@ -194,28 +230,21 @@ state_reductions_set (state_t *state, int nreductions, short *reductions)
 void
 state_rule_lookaheads_print (state_t *state, rule_t *rule, FILE *out)
 {
 void
 state_rule_lookaheads_print (state_t *state, rule_t *rule, FILE *out)
 {

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

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

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

     {
     {

+      bitset_iterator biter;
+      int k;
+      int not_first = 0;

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

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

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


@@ -325,13 +354,7 @@ void
 states_free (void)
 {
   state_number_t i;
 states_free (void)
 {
   state_number_t 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);

 }
 }