+
+ /*---------.
+ | States. |
+ `---------*/
+
+
+state_number nstates = 0;
+/* FINAL_STATE is properly set by new_state when it recognizes its
+ accessing symbol: $end. */
+state *final_state = NULL;
+
+
+/*------------------------------------------------------------------.
+| Create a new state with ACCESSING_SYMBOL, for those items. Store |
+| it in the state hash table. |
+`------------------------------------------------------------------*/
+
+state *
+state_new (symbol_number accessing_symbol,
+ size_t nitems, item_number *core)
+{
+ state *res;
+ size_t items_size = nitems * sizeof *core;
+
+ aver (nstates < STATE_NUMBER_MAXIMUM);
+
+ res = xmalloc (offsetof (state, items) + items_size);
+ res->number = nstates++;
+ res->accessing_symbol = accessing_symbol;
+ res->transitions = NULL;
+ res->reductions = NULL;
+ res->errs = NULL;
+ res->consistent = 0;
+ res->solved_conflicts = NULL;
+
+ res->nitems = nitems;
+ memcpy (res->items, core, items_size);
+
+ state_hash_insert (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 reductions of S. |
+`--------------------------*/
+
+void
+state_reductions_set (state *s, int num, rule **reds)
+{
+ 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;
+}
+
+
+/*--------------------.
+| Set the errs of S. |
+`--------------------*/
+
+void
+state_errs_set (state *s, int num, symbol **tokens)
+{
+ 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. */
+ if (reds->lookahead_tokens && red != -1)
+ {
+ bitset_iterator biter;
+ int k;
+ char const *sep = "";
+ fprintf (out, " [");
+ BITSET_FOR_EACH (biter, reds->lookahead_tokens[red], k, 0)
+ {
+ fprintf (out, "%s%s", sep, symbols[k]->tag);
+ sep = ", ";
+ }
+ fprintf (out, "]");
+ }
+}
+
+
+/*---------------------.
+| A state hash table. |
+`---------------------*/
+
+/* Initial capacity of states hash table. */
+#define HT_INITIAL_CAPACITY 257
+
+static struct hash_table *state_table = NULL;
+
+/* Two states are equal if they have the same core items. */
+static inline bool
+state_compare (state const *s1, state const *s2)
+{
+ size_t i;
+
+ if (s1->nitems != s2->nitems)
+ return false;
+
+ for (i = 0; i < s1->nitems; ++i)
+ if (s1->items[i] != s2->items[i])
+ return false;
+
+ return true;
+}
+
+static bool
+state_comparator (void const *s1, void const *s2)
+{
+ return state_compare (s1, s2);
+}
+
+static inline size_t
+state_hash (state const *s, size_t tablesize)
+{
+ /* Add up the state's item numbers to get a hash key. */
+ size_t key = 0;
+ size_t i;
+ for (i = 0; i < s->nitems; ++i)
+ key += s->items[i];
+ return key % tablesize;
+}
+
+static size_t
+state_hasher (void const *s, size_t tablesize)
+{
+ return state_hash (s, tablesize);
+}
+
+
projects / bison.git / blobdiff