X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/c7ca99d4b03860bb258914fbc228272031eec77c..43ca804096bad13b12d0933d14499c142f451af9:/src/state.c
diff --git a/src/state.c b/src/state.c
index 874c5863..666e0cc7 100644
--- a/src/state.c
+++ b/src/state.c
@@ -1,29 +1,31 @@
-/* Type definitions for nondeterministic finite state machine for bison,
- Copyright (C) 2001, 2002 Free Software Foundation, Inc.
+/* Type definitions for the finite state machine for Bison.
+
+ Copyright (C) 2001-2007, 2009-2012 Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
- Bison is free software; you can redistribute it and/or modify
+ This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2, or (at your option)
- any later version.
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
- Bison is distributed in the hope that it will be useful,
+ This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
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. */
-
+ along with this program. If not, see . */
+#include
#include "system.h"
-#include "hash.h"
+
+#include
+
#include "complain.h"
#include "gram.h"
#include "state.h"
+#include "print-xml.h"
/*-------------------.
@@ -31,23 +33,37 @@
`-------------------*/
-/*---------------------------------------.
-| Create a new array of N shifts/gotos. |
-`---------------------------------------*/
-
-#define SHIFTS_ALLOC(Nshifts) \
- (shifts *) xcalloc ((unsigned) (sizeof (shifts) \
- + (Nshifts - 1) * sizeof (short)), 1)
+/*-----------------------------------------.
+| Create a new array of NUM shifts/gotos. |
+`-----------------------------------------*/
-shifts *
-shifts_new (int n)
+static transitions *
+transitions_new (int num, state **the_states)
{
- shifts *res = SHIFTS_ALLOC (n);
- res->nshifts = n;
+ 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 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];
+ }
+}
/*--------------------.
@@ -55,29 +71,17 @@ shifts_new (int n)
`--------------------*/
-/*-------------------------------.
-| 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_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;
}
@@ -89,19 +93,18 @@ 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;
}
@@ -112,77 +115,190 @@ 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
- 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->number = nstates;
- ++nstates;
+ res->transitions = NULL;
+ res->reductions = NULL;
+ res->errs = NULL;
+ res->state_list = NULL;
+ res->consistent = 0;
+ res->solved_conflicts = NULL;
+ res->solved_conflicts_xml = NULL;
+
+ res->nitems = nitems;
+ memcpy (res->items, core, items_size);
+
+ state_hash_insert (res);
+
+ return res;
+}
+
+state *
+state_new_isocore (state const *s)
+{
+ state *res;
+ size_t items_size = s->nitems * sizeof *s->items;
+
+ aver (nstates < STATE_NUMBER_MAXIMUM);
+
+ res = xmalloc (offsetof (state, items) + items_size);
+ res->number = nstates++;
+ res->accessing_symbol = s->accessing_symbol;
+ res->transitions =
+ transitions_new (s->transitions->num, s->transitions->states);
+ res->reductions = reductions_new (s->reductions->num, s->reductions->rules);
+ res->errs = NULL;
+ res->state_list = NULL;
+ res->consistent = s->consistent;
res->solved_conflicts = NULL;
+ res->solved_conflicts_xml = NULL;
- res->nitems = core_size;
- memcpy (res->items, core, core_size * sizeof (core[0]));
+ res->nitems = s->nitems;
+ memcpy (res->items, s->items, items_size);
return res;
}
-/*--------------------------------------------------------------.
-| Print on OUT all the lookaheads such that this STATE wants to |
-| reduce this RULE. |
-`--------------------------------------------------------------*/
+/*---------.
+| 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_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. */
- if (nlookaheads)
+ if (reds->lookahead_tokens && red != -1)
{
+ bitset_iterator biter;
+ int k;
+ char const *sep = "";
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, "]");
}
}
+void
+state_rule_lookahead_tokens_print_xml (state *s, rule *r,
+ FILE *out, int level)
+{
+ /* 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;
+ xml_puts (out, level, "");
+ BITSET_FOR_EACH (biter, reds->lookahead_tokens[red], k, 0)
+ {
+ xml_printf (out, level + 1, "%s",
+ xml_escape (symbols[k]->tag));
+ }
+ xml_puts (out, level, "");
+ }
+}
+
+
+/*---------------------.
| A state hash table. |
-`----------------------*/
+`---------------------*/
/* Initial capacity of states hash table. */
#define HT_INITIAL_CAPACITY 257
@@ -190,32 +306,44 @@ 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 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)
- return FALSE;
+ return false;
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. */
- 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;
}
+static size_t
+state_hasher (void const *s, size_t tablesize)
+{
+ return state_hash (s, tablesize);
+}
+
/*-------------------------------.
| Create the states hash table. |
@@ -226,9 +354,9 @@ state_hash_new (void)
{
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);
}
@@ -243,14 +371,15 @@ state_hash_free (void)
}
-/*---------------------------------------.
-| Insert STATE in the state hash table. |
-`---------------------------------------*/
+/*-----------------------------------.
+| Insert S in the state hash table. |
+`-----------------------------------*/
void
-state_hash_insert (state_t *state)
+state_hash_insert (state *s)
{
- hash_insert (state_table, state);
+ if (!hash_insert (state_table, s))
+ xalloc_die ();
}
@@ -259,21 +388,68 @@ state_hash_insert (state_t *state)
| 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;
}
+
+/*--------------------------------------------------------.
+| 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_t **states = NULL;
+state **states = NULL;
/*----------------------.
@@ -283,14 +459,8 @@ state_t **states = NULL;
void
states_free (void)
{
- state_number_t i;
-
+ state_number 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);
}