/* Match rules with nonterminals for bison,
- Copyright (C) 1984, 1989, 2000 Free Software Foundation, Inc.
+ Copyright 1984, 1989, 2000, 2001 Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
Boston, MA 02111-1307, USA. */
-/* 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 "system.h"
-#include "alloc.h"
+#include "getargs.h"
+#include "symtab.h"
#include "types.h"
+#include "reader.h"
#include "gram.h"
#include "derives.h"
-short **derives;
-
-#if DEBUG
+short **derives = NULL;
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]);
+ short *sp;
+ fprintf (stderr, "\t%s derives\n", symbols[i]->tag);
for (sp = derives[i]; *sp > 0; sp++)
{
- printf (" %d", *sp);
+ short *rhsp;
+ fprintf (stderr, "\t\t%d:", *sp);
+ for (rhsp = &ritem[rules[*sp].rhs]; *rhsp >= 0; ++rhsp)
+ fprintf (stderr, " %s", symbols[*rhsp]->tag);
+ fprintf (stderr, " (rule %d)\n", -*rhsp - 1);
}
- putchar ('\n');
}
- putchar ('\n');
+ fputs ("\n\n", stderr);
}
-#endif
void
set_derives (void)
{
- register int i;
- register int lhs;
- register shorts *p;
- register short *q;
- register shorts **dset;
- register shorts *delts;
+ int i;
+ shorts *p;
+ short *q;
+ shorts **dset;
+ shorts *delts;
- dset = NEW2 (nvars, shorts *) - ntokens;
- delts = NEW2 (nrules + 1, shorts);
+ dset = XCALLOC (shorts *, nvars) - ntokens;
+ delts = XCALLOC (shorts, nrules + 1);
p = delts;
for (i = nrules; i > 0; i--)
- {
- lhs = rlhs[i];
- if (lhs >= 0)
- {
- p->next = dset[lhs];
- p->value = i;
- dset[lhs] = p;
- p++;
- }
- }
-
- derives = NEW2 (nvars, short *) - ntokens;
- q = NEW2 (nvars + nrules, short);
+ if (rules[i].useful)
+ {
+ int lhs = rules[i].lhs;
+ p->next = dset[lhs];
+ p->value = i;
+ dset[lhs] = p;
+ p++;
+ }
+
+ derives = XCALLOC (short *, nvars) - ntokens;
+ q = XCALLOC (short, nvars + nrules);
for (i = ntokens; i < nsyms; i++)
{
*q++ = -1;
}
-#if DEBUG
- print_derives ();
-#endif
+ if (trace_flag)
+ print_derives ();
- FREE (dset + ntokens);
- FREE (delts);
+ XFREE (dset + ntokens);
+ XFREE (delts);
}
void
free_derives (void)
{
- FREE (derives[ntokens]);
- FREE (derives + ntokens);
+ XFREE (derives[ntokens]);
+ XFREE (derives + ntokens);
}