Files
bison/src/derives.c
Akim Demaille 80a6975034 * src/derives.c (print_derives): Display the ruleno.
* src/lalr.c (initialize_F, transpose): Better variable locality
to improve readability.
Avoid variables used as mere abbreviations.
2001-12-05 09:28:00 +00:00

107 lines
2.2 KiB
C

/* Match rules with nonterminals for bison,
Copyright 1984, 1989, 2000, 2001 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
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.
Bison 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. */
#include "system.h"
#include "getargs.h"
#include "types.h"
#include "reader.h"
#include "gram.h"
#include "derives.h"
short **derives = NULL;
static void
print_derives (void)
{
int i;
fputs ("DERIVES\n", stderr);
for (i = ntokens; i < nsyms; i++)
{
short *sp;
fprintf (stderr, "\t%s derives\n", tags[i]);
for (sp = derives[i]; *sp > 0; sp++)
{
short *rhsp;
fprintf (stderr, "\t\t%d:", *sp);
for (rhsp = ritem + rule_table[*sp].rhs; *rhsp > 0; ++rhsp)
fprintf (stderr, " %s", tags[*rhsp]);
fprintf (stderr, " (rule %d)\n", -*rhsp);
}
}
fputs ("\n\n", 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 (rule_table[i].useful)
{
int lhs = rule_table[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++)
{
derives[i] = q;
p = dset[i];
while (p)
{
*q++ = p->value;
p = p->next;
}
*q++ = -1;
}
if (trace_flag)
print_derives ();
XFREE (dset + ntokens);
XFREE (delts);
}
void
free_derives (void)
{
XFREE (derives[ntokens]);
XFREE (derives + ntokens);
}