X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/c21493b89f5f5dd49e1f46d311326d5d4f49f8a4..bb8e56ff67d289d15f1a4dc7f5e1502cd3bbfc24:/src/state.c
diff --git a/src/state.c b/src/state.c
index 83e0108f..c1ac3f17 100644
--- a/src/state.c
+++ b/src/state.c
@@ -1,24 +1,21 @@
-/* Type definitions for nondeterministic finite state machine for Bison.
+/* Type definitions for the finite state machine for Bison.
- Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006 Free Software
- Foundation, Inc.
+ 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., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see . */
#include
#include "system.h"
@@ -28,11 +25,12 @@
#include "complain.h"
#include "gram.h"
#include "state.h"
+#include "print-xml.h"
- /*-------------------.
- | Shifts and Gotos. |
- `-------------------*/
+ /*-------------------.
+ | Shifts and Gotos. |
+ `-------------------*/
/*-----------------------------------------.
@@ -61,17 +59,16 @@ transitions_to (transitions *shifts, symbol_number sym)
int j;
for (j = 0; ; j++)
{
- if (shifts->num <= j)
- abort ();
+ aver (j < shifts->num);
if (TRANSITION_SYMBOL (shifts, j) == sym)
- return shifts->states[j];
+ return shifts->states[j];
}
}
- /*--------------------.
- | Error transitions. |
- `--------------------*/
+ /*--------------------.
+ | Error transitions. |
+ `--------------------*/
/*---------------------------------.
@@ -91,9 +88,9 @@ errs_new (int num, symbol **tokens)
- /*-------------.
- | Reductions. |
- `-------------*/
+ /*-------------.
+ | Reductions. |
+ `-------------*/
/*---------------------------------------.
@@ -106,16 +103,16 @@ reductions_new (int num, rule **reds)
size_t rules_size = num * sizeof *reds;
reductions *res = xmalloc (offsetof (reductions, rules) + rules_size);
res->num = num;
- res->look_ahead_tokens = NULL;
+ res->lookahead_tokens = NULL;
memcpy (res->rules, reds, rules_size);
return res;
}
- /*---------.
- | States. |
- `---------*/
+ /*---------.
+ | States. |
+ `---------*/
state_number nstates = 0;
@@ -131,13 +128,12 @@ state *final_state = NULL;
state *
state_new (symbol_number accessing_symbol,
- size_t nitems, 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 = xmalloc (offsetof (state, items) + items_size);
res->number = nstates++;
@@ -145,8 +141,10 @@ state_new (symbol_number accessing_symbol,
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);
@@ -156,6 +154,32 @@ state_new (symbol_number accessing_symbol,
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 = s->nitems;
+ memcpy (res->items, s->items, items_size);
+
+ return res;
+}
+
/*---------.
| Free S. |
@@ -178,7 +202,7 @@ state_free (state *s)
void
state_transitions_set (state *s, int num, state **trans)
{
- assert (!s->transitions);
+ aver (!s->transitions);
s->transitions = transitions_new (num, trans);
}
@@ -190,7 +214,7 @@ state_transitions_set (state *s, int num, state **trans)
void
state_reductions_set (state *s, int num, rule **reds)
{
- assert (!s->reductions);
+ aver (!s->reductions);
s->reductions = reductions_new (num, reds);
}
@@ -214,41 +238,63 @@ state_reduction_find (state *s, rule *r)
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 look-ahead tokens such that S |
-| wants to reduce R. |
-`---------------------------------------------------*/
+/*--------------------------------------------------.
+| Print on OUT all the lookahead tokens such that S |
+| wants to reduce R. |
+`--------------------------------------------------*/
void
-state_rule_look_ahead_tokens_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->look_ahead_tokens && red != -1)
+ if (reds->lookahead_tokens && red != -1)
{
bitset_iterator biter;
int k;
char const *sep = "";
fprintf (out, " [");
- BITSET_FOR_EACH (biter, reds->look_ahead_tokens[red], k, 0)
- {
- fprintf (out, "%s%s", sep, symbols[k]->tag);
- sep = ", ";
- }
+ 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. |
@@ -307,10 +353,10 @@ void
state_hash_new (void)
{
state_table = hash_initialize (HT_INITIAL_CAPACITY,
- NULL,
- state_hasher,
- state_comparator,
- NULL);
+ NULL,
+ state_hasher,
+ state_comparator,
+ NULL);
}
@@ -332,7 +378,8 @@ state_hash_free (void)
void
state_hash_insert (state *s)
{
- hash_insert (state_table, s);
+ if (!hash_insert (state_table, s))
+ xalloc_die ();
}
@@ -355,6 +402,52 @@ state_hash_lookup (size_t nitems, item_number *core)
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;