/* Match rules with nonterminals for bison,
- Copyright 1984, 1989, 2000, 2001 Free Software Foundation, Inc.
+ Copyright 1984, 1989, 2000, 2001, 2002 Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
#include "gram.h"
#include "derives.h"
-short **derives = NULL;
+/* Linked list of rule numbers. */
+typedef struct rule_list_s
+{
+ struct rule_list_s *next;
+ rule_number_t value;
+} rule_list_t;
+
+rule_number_t **derives = NULL;
static void
print_derives (void)
for (i = ntokens; i < nsyms; i++)
{
- short *sp;
+ rule_number_t *rp;
fprintf (stderr, "\t%s derives\n", symbols[i]->tag);
- for (sp = derives[i]; *sp > 0; sp++)
+ for (rp = derives[i]; *rp > 0; rp++)
{
- short *rhsp;
- fprintf (stderr, "\t\t%d:", *sp);
- for (rhsp = rules[*sp].rhs; *rhsp >= 0; ++rhsp)
- fprintf (stderr, " %s", symbols[*rhsp]->tag);
- fprintf (stderr, " (rule %d)\n", -*rhsp - 1);
+ fprintf (stderr, "\t\t%3d ", *rp - 1);
+ rule_rhs_print (&rules[*rp], stderr);
}
}
void
set_derives (void)
{
- int i;
- shorts *p;
- short *q;
- shorts **dset;
- shorts *delts;
-
- dset = XCALLOC (shorts *, nvars) - ntokens;
- delts = XCALLOC (shorts, nrules + 1);
-
- p = delts;
- for (i = nrules; i > 0; i--)
- 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);
+ symbol_number_t i;
+ rule_number_t r;
+ rule_number_t *q;
+
+ /* DSET[NTERM] -- A linked list of the numbers of the rules whose
+ LHS is NTERM. */
+ rule_list_t **dset = XCALLOC (rule_list_t *, nvars) - ntokens;
+
+ /* 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_t *delts = XCALLOC (rule_list_t, nrules + 1);
+
+ for (r = nrules; r > 0; r--)
+ {
+ symbol_number_t lhs = rules[r].lhs->number;
+ rule_list_t *p = &delts[r];
+ /* A new LHS is found. */
+ p->next = dset[lhs];
+ p->value = r;
+ dset[lhs] = p;
+ }
+
+ /* DSET contains what we need under the form of a linked list. Make
+ it a single array. */
+
+ derives = XCALLOC (rule_number_t *, nvars) - ntokens;
+ q = XCALLOC (rule_number_t, nvars + int_of_rule_number (nrules));
for (i = ntokens; i < nsyms; i++)
{
+ rule_list_t *p = dset[i];
derives[i] = q;
- p = dset[i];
while (p)
{
*q++ = p->value;
if (trace_flag)
print_derives ();
- XFREE (dset + ntokens);
- XFREE (delts);
+ free (dset + ntokens);
+ free (delts);
}
+
void
free_derives (void)
{