X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/b2ca4022ea6c61e10ac87a0a92bb0f998ecf8b48..0fe9720964da510a2b359af390a3053aace65f9f:/src/derives.c
diff --git a/src/derives.c b/src/derives.c
index 3c1d3f62..aa4d927f 100644
--- a/src/derives.c
+++ b/src/derives.c
@@ -1,114 +1,120 @@
/* Match rules with nonterminals for bison,
- Copyright (C) 1984, 1989, 2000 Free Software Foundation, Inc.
+
+ Copyright (C) 1984, 1989, 2000-2003, 2005, 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"
-/* set_derives finds, for each variable (nonterminal), which rules can
- derive it. It sets up the value of derives so that derives[i -
- ntokens] points to a vector of rule numbers, terminated with -1.
- */
+#include "getargs.h"
-#include "system.h"
-#include "alloc.h"
-#include "types.h"
-#include "gram.h"
#include "derives.h"
+#include "gram.h"
+#include "reader.h"
+#include "symtab.h"
+
+/* Linked list of rule numbers. */
+typedef struct rule_list
+{
+ struct rule_list *next;
+ rule *value;
+} rule_list;
-#if DEBUG
+rule ***derives;
static void
print_derives (void)
{
- register int i;
- register short *sp;
+ int i;
- printf (_("\n\n\nDERIVES\n\n"));
+ fputs ("DERIVES\n", stderr);
for (i = ntokens; i < nsyms; i++)
{
- printf (_("%s derives"), tags[i]);
- for (sp = derives[i]; *sp > 0; sp++)
- {
- printf (" %d", *sp);
- }
- putchar ('\n');
+ rule **rp;
+ fprintf (stderr, " %s derives\n", symbols[i]->tag);
+ for (rp = derives[i - ntokens]; *rp; ++rp)
+ {
+ fprintf (stderr, " %3d ", (*rp)->user_number);
+ rule_rhs_print (*rp, stderr);
+ fprintf (stderr, "\n");
+ }
}
- putchar ('\n');
+ fputs ("\n\n", stderr);
}
-#endif
-
-short **derives;
void
-set_derives (void)
+derives_compute (void)
{
- register int i;
- register int lhs;
- register shorts *p;
- register short *q;
- register shorts **dset;
- register shorts *delts;
-
- dset = NEW2 (nvars, shorts *) - ntokens;
- delts = NEW2 (nrules + 1, shorts);
-
- p = delts;
- for (i = nrules; i > 0; i--)
+ symbol_number i;
+ rule_number r;
+ rule **q;
+
+ /* DSET[NTERM - NTOKENS] -- A linked list of the numbers of the rules
+ whose LHS is NTERM. */
+ rule_list **dset = xcalloc (nvars, sizeof *dset);
+
+ /* DELTS[RULE] -- There are NRULES rule number to attach to nterms.
+ Instead of performing NRULES allocations for each, have an array
+ indexed by rule numbers. */
+ rule_list *delts = xnmalloc (nrules, sizeof *delts);
+
+ for (r = nrules - 1; r >= 0; --r)
{
- lhs = rlhs[i];
- if (lhs >= 0)
- {
- p->next = dset[lhs];
- p->value = i;
- dset[lhs] = p;
- p++;
- }
+ symbol_number lhs = rules[r].lhs->number;
+ rule_list *p = &delts[r];
+ /* A new LHS is found. */
+ p->next = dset[lhs - ntokens];
+ p->value = &rules[r];
+ dset[lhs - ntokens] = p;
}
- derives = NEW2 (nvars, short *) - ntokens;
- q = NEW2 (nvars + nrules, short);
+ /* DSET contains what we need under the form of a linked list. Make
+ it a single array. */
+
+ derives = xnmalloc (nvars, sizeof *derives);
+ q = xnmalloc (nvars + nrules, sizeof *q);
for (i = ntokens; i < nsyms; i++)
{
- derives[i] = q;
- p = dset[i];
+ rule_list *p = dset[i - ntokens];
+ derives[i - ntokens] = q;
while (p)
- {
- *q++ = p->value;
- p = p->next;
- }
- *q++ = -1;
+ {
+ *q++ = p->value;
+ p = p->next;
+ }
+ *q++ = NULL;
}
-#if DEBUG
- print_derives ();
-#endif
+ if (trace_flag & trace_sets)
+ print_derives ();
- FREE (dset + ntokens);
- FREE (delts);
+ free (dset);
+ free (delts);
}
+
void
-free_derives (void)
+derives_free (void)
{
- FREE (derives[ntokens]);
- FREE (derives + ntokens);
+ free (derives[0]);
+ free (derives);
}