/* Type definitions for nondeterministic finite state machine for Bison.
- Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006 Free Software
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software
Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
int j;
for (j = 0; ; j++)
{
- assert (j < shifts->num);
+ aver (j < shifts->num);
if (TRANSITION_SYMBOL (shifts, j) == sym)
return shifts->states[j];
}
state *res;
size_t items_size = nitems * sizeof *core;
- assert (nstates < STATE_NUMBER_MAXIMUM);
+ aver (nstates < STATE_NUMBER_MAXIMUM);
res = xmalloc (offsetof (state, items) + items_size);
res->number = nstates++;
void
state_transitions_set (state *s, int num, state **trans)
{
- assert (!s->transitions);
+ aver (!s->transitions);
s->transitions = transitions_new (num, trans);
}
void
state_reductions_set (state *s, int num, rule **reds)
{
- assert (!s->reductions);
+ aver (!s->reductions);
s->reductions = reductions_new (num, reds);
}
void
state_errs_set (state *s, int num, symbol **tokens)
{
- assert (!s->errs);
+ aver (!s->errs);
s->errs = errs_new (num, tokens);
}
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. */
state **states = NULL;