/* Type definitions for nondeterministic finite state machine for Bison.
- Copyright (C) 2001, 2002 Free Software Foundation, Inc.
+
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software
+ Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
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 <hash.h>
`-------------------*/
-/*---------------------------------------.
-| Create a new array of N shifts/gotos. |
-`---------------------------------------*/
-
-#define TRANSITIONS_ALLOC(Num) \
- (transitions *) xcalloc ((sizeof (transitions) \
- + (Num - 1) * sizeof (state *)), \
- 1)
+/*-----------------------------------------.
+| Create a new array of NUM shifts/gotos. |
+`-----------------------------------------*/
static transitions *
transitions_new (int num, state **the_states)
{
- transitions *res = TRANSITIONS_ALLOC (num);
+ size_t states_size = num * sizeof *the_states;
+ transitions *res = xmalloc (offsetof (transitions, states) + states_size);
res->num = num;
- memcpy (res->states, the_states, num * sizeof (the_states[0]));
+ memcpy (res->states, the_states, states_size);
return res;
}
-/*-------------------------------------------------------------------.
-| Return the state such these TRANSITIONS contain a shift/goto to it |
-| on S. Abort if none found. |
-`-------------------------------------------------------------------*/
+/*-------------------------------------------------------.
+| 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 s)
+transitions_to (transitions *shifts, symbol_number sym)
{
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];
+ }
}
`--------------------*/
-/*-------------------------------.
-| Create a new array of N errs. |
-`-------------------------------*/
-
-#define ERRS_ALLOC(Nerrs) \
- ((errs *) xcalloc ((sizeof (errs) + (Nerrs - 1) * sizeof (symbol *)), 1))
-
+/*---------------------------------.
+| Create a new array of NUM errs. |
+`---------------------------------*/
errs *
errs_new (int num, symbol **tokens)
{
- errs *res = ERRS_ALLOC (num);
+ size_t symbols_size = num * sizeof *tokens;
+ errs *res = xmalloc (offsetof (errs, symbols) + symbols_size);
res->num = num;
- memcpy (res->symbols, tokens, num * sizeof (tokens[0]));
+ memcpy (res->symbols, tokens, symbols_size);
return res;
}
`-------------*/
-/*-------------------------------------.
-| Create a new array of N reductions. |
-`-------------------------------------*/
-
-#define REDUCTIONS_ALLOC(Nreductions) \
- (reductions *) xcalloc ((sizeof (reductions) \
- + (Nreductions - 1) * sizeof (rule *)), 1)
+/*---------------------------------------.
+| Create a new array of NUM reductions. |
+`---------------------------------------*/
static reductions *
reductions_new (int num, rule **reds)
{
- reductions *res = REDUCTIONS_ALLOC (num);
+ size_t rules_size = num * sizeof *reds;
+ reductions *res = xmalloc (offsetof (reductions, rules) + rules_size);
res->num = num;
- memcpy (res->rules, reds, num * sizeof (reds[0]));
- res->lookaheads = NULL;
+ res->lookahead_tokens = NULL;
+ memcpy (res->rules, reds, rules_size);
return res;
}
accessing symbol: $end. */
state *final_state = NULL;
-#define STATE_ALLOC(Nitems) \
- (state *) xcalloc ((sizeof (state) \
- + (Nitems - 1) * sizeof (item_number)), \
- 1)
/*------------------------------------------------------------------.
| Create a new state with ACCESSING_SYMBOL, for those items. Store |
state *
state_new (symbol_number accessing_symbol,
- size_t core_size, item_number *core)
+ size_t nitems, item_number *core)
{
state *res;
+ size_t items_size = nitems * sizeof *core;
- if (STATE_NUMBER_MAXIMUM <= nstates)
- abort ();
+ 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->number = nstates;
- ++nstates;
+ res->transitions = NULL;
+ res->reductions = NULL;
+ res->errs = NULL;
+ res->consistent = 0;
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);
void
state_transitions_set (state *s, int num, state **trans)
{
- if (s->transitions)
- abort ();
+ aver (!s->transitions);
s->transitions = transitions_new (num, trans);
}
void
state_reductions_set (state *s, int num, rule **reds)
{
- if (s->reductions)
- abort ();
+ aver (!s->reductions);
s->reductions = reductions_new (num, reds);
}
void
state_errs_set (state *s, int num, symbol **tokens)
{
- if (s->errs)
- abort ();
+ aver (!s->errs);
s->errs = errs_new (num, tokens);
}
-/*-----------------------------------------------------.
-| Print on OUT all the lookaheads such that S wants to |
-| reduce R. |
-`-----------------------------------------------------*/
+/*--------------------------------------------------.
+| Print on OUT all the lookahead tokens such that S |
+| wants to reduce R. |
+`--------------------------------------------------*/
void
-state_rule_lookaheads_print (state *s, rule *r, FILE *out)
+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->lookaheads && red != -1)
+ if (reds->lookahead_tokens && red != -1)
{
bitset_iterator biter;
int k;
- int not_first = 0;
+ char const *sep = "";
fprintf (out, " [");
- BITSET_FOR_EACH (biter, reds->lookaheads[red], k, 0)
- fprintf (out, "%s%s",
- not_first++ ? ", " : "",
- symbols[k]->tag);
+ 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 bool
+static inline bool
state_compare (state const *s1, state const *s2)
{
- int i;
+ size_t i;
if (s1->nitems != s2->nitems)
return false;
return true;
}
-static unsigned int
-state_hash (state const *s, unsigned int tablesize)
+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. */
- int key = 0;
- int i;
+ 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);
+}
+
/*-------------------------------.
| Create the states hash table. |
{
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);
}
`------------------------------------------------------------------*/
state *
-state_hash_lookup (size_t core_size, item_number *core)
+state_hash_lookup (size_t nitems, item_number *core)
{
- state *probe = STATE_ALLOC (core_size);
+ 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;
}
+
+/*--------------------------------------------------------.
+| 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;
projects / bison.git / blobdiff