bison/src/gram.c

/* Allocate input grammar variables for Bison.

   Copyright (C) 1984, 1986, 1989, 2001, 2002, 2003, 2005, 2006, 2007,
   2008, 2009, 2010 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

   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 3 of the License, or
   (at your option) any later version.

   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 this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include <config.h>
#include "system.h"

#include <quotearg.h>

#include "complain.h"
#include "gram.h"
#include "print-xml.h"
#include "reader.h"
#include "reduce.h"
#include "symtab.h"

/* Comments for these variables are in gram.h.  */

item_number *ritem = NULL;
unsigned int nritems = 0;

rule *rules = NULL;
rule_number nrules = 0;

symbol **symbols = NULL;
int nsyms = 0;
int ntokens = 1;
int nvars = 0;

symbol_number *token_translations = NULL;

int max_user_token_number = 256;

bool
rule_useful_in_grammar_p (rule *r)
{
  return r->number < nrules;
}

bool
rule_useless_in_grammar_p (rule *r)
{
  return !rule_useful_in_grammar_p (r);
}

bool
rule_useless_in_parser_p (rule *r)
{
  return !r->useful && rule_useful_in_grammar_p (r);
}

void
rule_lhs_print (rule *r, symbol *previous_lhs, FILE *out)
{
  fprintf (out, "  %3d ", r->number);
  if (previous_lhs != r->lhs)
    {
      fprintf (out, "%s:", r->lhs->tag);
    }
  else
    {
      int n;
      for (n = strlen (previous_lhs->tag); n > 0; --n)
	fputc (' ', out);
      fputc ('|', out);
    }
}

void
rule_lhs_print_xml (rule *r, FILE *out, int level)
{
  xml_printf (out, level, "<lhs>%s</lhs>", r->lhs->tag);
}

int
rule_rhs_length (rule *r)
{
  int res = 0;
  item_number *rhsp;
  for (rhsp = r->rhs; *rhsp >= 0; ++rhsp)
    ++res;
  return res;
}

void
rule_rhs_print (rule *r, FILE *out)
{
  if (*r->rhs >= 0)
    {
      item_number *rp;
      for (rp = r->rhs; *rp >= 0; rp++)
	fprintf (out, " %s", symbols[*rp]->tag);
      fputc ('\n', out);
    }
  else
    {
      fprintf (out, " /* %s */\n", _("empty"));
    }
}

static void
rule_rhs_print_xml (rule *r, FILE *out, int level)
{
  if (*r->rhs >= 0)
    {
      item_number *rp;
      xml_puts (out, level, "<rhs>");
      for (rp = r->rhs; *rp >= 0; rp++)
	xml_printf (out, level + 1, "<symbol>%s</symbol>",
		    xml_escape (symbols[*rp]->tag));
      xml_puts (out, level, "</rhs>");
    }
  else
    {
      xml_puts (out, level, "<rhs>");
      xml_puts (out, level + 1, "<empty/>");
      xml_puts (out, level, "</rhs>");
    }
}

void
rule_print (rule *r, FILE *out)
{
  fprintf (out, "%s:", r->lhs->tag);
  rule_rhs_print (r, out);
}

void
ritem_print (FILE *out)
{
  unsigned int i;
  fputs ("RITEM\n", out);
  for (i = 0; i < nritems; ++i)
    if (ritem[i] >= 0)
      fprintf (out, "  %s", symbols[ritem[i]]->tag);
    else
      fprintf (out, "  (rule %d)\n", item_number_as_rule_number (ritem[i]));
  fputs ("\n\n", out);
}

size_t
ritem_longest_rhs (void)
{
  int max = 0;
  rule_number r;

  for (r = 0; r < nrules; ++r)
    {
      int length = rule_rhs_length (&rules[r]);
      if (length > max)
	max = length;
    }

  return max;
}

void
grammar_rules_partial_print (FILE *out, const char *title,
			     rule_filter filter)
{
  rule_number r;
  bool first = true;
  symbol *previous_lhs = NULL;

  /* rule # : LHS -> RHS */
  for (r = 0; r < nrules + nuseless_productions; r++)
    {
      if (filter && !filter (&rules[r]))
	continue;
      if (first)
	fprintf (out, "%s\n\n", title);
      else if (previous_lhs && previous_lhs != rules[r].lhs)
	fputc ('\n', out);
      first = false;
      rule_lhs_print (&rules[r], previous_lhs, out);
      rule_rhs_print (&rules[r], out);
      previous_lhs = rules[r].lhs;
    }
  if (!first)
    fputs ("\n\n", out);
}

void
grammar_rules_print (FILE *out)
{
  grammar_rules_partial_print (out, _("Grammar"), rule_useful_in_grammar_p);
}

void
grammar_rules_print_xml (FILE *out, int level)
{
  rule_number r;
  bool first = true;

  for (r = 0; r < nrules + nuseless_productions; r++)
    {
      if (first)
	xml_puts (out, level + 1, "<rules>");
      first = false;
      {
        char const *usefulness;
        if (rule_useless_in_grammar_p (&rules[r]))
          usefulness = "useless-in-grammar";
        else if (rule_useless_in_parser_p (&rules[r]))
          usefulness = "useless-in-parser";
        else
          usefulness = "useful";
        xml_indent (out, level + 2);
        fprintf (out, "<rule number=\"%d\" usefulness=\"%s\"",
                 rules[r].number, usefulness);
        if (rules[r].precsym)
          fprintf (out, " percent_prec=\"%s\"",
                   xml_escape (rules[r].precsym->tag));
        fputs (">\n", out);
      }
      rule_lhs_print_xml (&rules[r], out, level + 3);
      rule_rhs_print_xml (&rules[r], out, level + 3);
      xml_puts (out, level + 2, "</rule>");
    }
  if (!first)
    xml_puts (out, level + 1, "</rules>");
  else
   xml_puts (out, level + 1, "<rules/>");
}

void
grammar_dump (FILE *out, const char *title)
{
  fprintf (out, "%s\n\n", title);
  fprintf (out,
	   "ntokens = %d, nvars = %d, nsyms = %d, nrules = %d, nritems = %d\n\n",
	   ntokens, nvars, nsyms, nrules, nritems);


  fprintf (out, "Variables\n---------\n\n");
  {
    symbol_number i;
    fprintf (out, "Value  Sprec  Sassoc  Tag\n");

    for (i = ntokens; i < nsyms; i++)
      fprintf (out, "%5d  %5d   %5d  %s\n",
	       i,
	       symbols[i]->prec, symbols[i]->assoc,
	       symbols[i]->tag);
    fprintf (out, "\n\n");
  }

  fprintf (out, "Rules\n-----\n\n");
  {
    rule_number i;
    fprintf (out, "Num (Prec, Assoc, Useful, Ritem Range) Lhs -> Rhs (Ritem range) [Num]\n");
    for (i = 0; i < nrules + nuseless_productions; i++)
      {
	rule *rule_i = &rules[i];
	item_number *rp = NULL;
	unsigned int rhs_itemno = rule_i->rhs - ritem;
	unsigned int rhs_count = 0;
	/* Find the last RHS index in ritems. */
	for (rp = rule_i->rhs; *rp >= 0; ++rp)
	  ++rhs_count;
	fprintf (out, "%3d (%2d, %2d, %2d, %2u-%2u)   %2d ->",
		 i,
		 rule_i->prec ? rule_i->prec->prec : 0,
		 rule_i->prec ? rule_i->prec->assoc : 0,
		 rule_i->useful,
		 rhs_itemno,
		 rhs_itemno + rhs_count - 1,
		 rule_i->lhs->number);
	/* Dumped the RHS. */
	for (rp = rule_i->rhs; *rp >= 0; rp++)
	  fprintf (out, " %3d", *rp);
	fprintf (out, "  [%d]\n", item_number_as_rule_number (*rp));
      }
  }
  fprintf (out, "\n\n");

  fprintf (out, "Rules interpreted\n-----------------\n\n");
  {
    rule_number r;
    for (r = 0; r < nrules + nuseless_productions; r++)
      {
	fprintf (out, "%-5d  ", r);
	rule_print (&rules[r], out);
      }
  }
  fprintf (out, "\n\n");
}

void
grammar_rules_useless_report (const char *message)
{
  rule_number r;
  for (r = 0; r < nrules ; ++r)
    if (!rules[r].useful)
      {
        warn_at (rules[r].location, "%s: ", message);
        rule_print (&rules[r], stderr);
        fflush (stderr);
      }
}

void
grammar_free (void)
{
  if (ritem)
    free (ritem - 1);
  free (rules);
  free (token_translations);
  /* Free the symbol table data structure.  */
  symbols_free ();
  free_merger_functions ();
}