output.c

bison 2.0 主要可以用来做语法分析用的

/* Output the generated parsing program for Bison.

   Copyright (C) 1984, 1986, 1989, 1992, 2000, 2001, 2002, 2003, 2004
   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 <error.h>
#include <get-errno.h>
#include <quotearg.h>
#include <subpipe.h>
#include <timevar.h>

#include "complain.h"
#include "files.h"
#include "getargs.h"
#include "gram.h"
#include "muscle_tab.h"
#include "output.h"
#include "reader.h"
#include "symtab.h"
#include "tables.h"

/* From src/scan-skel.l. */
void scan_skel (FILE *);


static struct obstack format_obstack;

bool error_verbose = false;



/*-------------------------------------------------------------------.
| Create a function NAME which associates to the muscle NAME the     |
| result of formatting the FIRST and then TABLE_DATA[BEGIN..END[ (of |
| TYPE), and to the muscle NAME_max, the max value of the            |
| TABLE_DATA.                                                        |
`-------------------------------------------------------------------*/


#define GENERATE_MUSCLE_INSERT_TABLE(Name, Type)			\
									\
static void								\
Name (const char *name,							\
      Type *table_data,							\
      Type first,							\
      int begin,							\
      int end)								\
{									\
  Type min = first;							\
  Type max = first;							\
  long int lmin;							\
  long int lmax;							\
  int i;								\
  int j = 1;								\
									\
  obstack_fgrow1 (&format_obstack, "%6d", first);			\
  for (i = begin; i < end; ++i)						\
    {									\
      obstack_1grow (&format_obstack, ',');				\
      if (j >= 10)							\
	{								\
	  obstack_sgrow (&format_obstack, "\n  ");			\
	  j = 1;							\
	}								\
      else								\
	++j;								\
      obstack_fgrow1 (&format_obstack, "%6d", table_data[i]);		\
      if (table_data[i] < min)						\
	min = table_data[i];						\
      if (max < table_data[i])						\
	max = table_data[i];						\
    }									\
  obstack_1grow (&format_obstack, 0);					\
  muscle_insert (name, obstack_finish (&format_obstack));		\
									\
  lmin = min;								\
  lmax = max;								\
  /* Build `NAME_min' and `NAME_max' in the obstack. */			\
  obstack_fgrow1 (&format_obstack, "%s_min", name);			\
  obstack_1grow (&format_obstack, 0);					\
  MUSCLE_INSERT_LONG_INT (obstack_finish (&format_obstack), lmin);	\
  obstack_fgrow1 (&format_obstack, "%s_max", name);			\
  obstack_1grow (&format_obstack, 0);					\
  MUSCLE_INSERT_LONG_INT (obstack_finish (&format_obstack), lmax);	\
}

GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_unsigned_int_table, unsigned int)
GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_int_table, int)
GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_base_table, base_number)
GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_rule_number_table, rule_number)
GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_symbol_number_table, symbol_number)
GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_item_number_table, item_number)
GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_state_number_table, state_number)


/*----------------------------------------------------------------------.
| Print to OUT a representation of FILENAME escaped both for C and M4.  |
`----------------------------------------------------------------------*/

static void
escaped_file_name_output (FILE *out, char const *filename)
{
  char const *p;
  fprintf (out, "[[");

  for (p = quotearg_style (c_quoting_style, filename); *p; p++)
    switch (*p)
      {
      case '$': fputs ("$][", out); break;
      case '@': fputs ("@@",  out); break;
      case '[': fputs ("@{",  out); break;
      case ']': fputs ("@}",  out); break;
      default: fputc (*p, out); break;
      }

  fprintf (out, "]]");
}


/*------------------------------------------------------------------.
| Prepare the muscles related to the symbols: translate, tname, and |
| toknum.                                                           |
`------------------------------------------------------------------*/

static void
prepare_symbols (void)
{
  MUSCLE_INSERT_INT ("tokens_number", ntokens);
  MUSCLE_INSERT_INT ("nterms_number", nvars);
  MUSCLE_INSERT_INT ("undef_token_number", undeftoken->number);
  MUSCLE_INSERT_INT ("user_token_number_max", max_user_token_number);

  muscle_insert_symbol_number_table ("translate",
				     token_translations,
				     token_translations[0],
				     1, max_user_token_number + 1);

  /* tname -- token names.  */
  {
    int i;
    /* We assume that the table will be output starting at column 2. */
    int j = 2;
    for (i = 0; i < nsyms; i++)
      {
	const char *cp = quotearg_style (c_quoting_style, symbols[i]->tag);
	/* Width of the next token, including the two quotes, the
	   comma and the space.  */
	int width = strlen (cp) + 2;

	if (j + width > 75)
	  {
	    obstack_sgrow (&format_obstack, "\n ");
	    j = 1;
	  }

	if (i)
	  obstack_1grow (&format_obstack, ' ');
	MUSCLE_OBSTACK_SGROW (&format_obstack, cp);
	obstack_1grow (&format_obstack, ',');
	j += width;
      }
    /* Add a NULL entry to list of tokens (well, 0, as NULL might not be
       defined).  */
    obstack_sgrow (&format_obstack, " 0");

    /* Finish table and store. */
    obstack_1grow (&format_obstack, 0);
    muscle_insert ("tname", obstack_finish (&format_obstack));
  }

  /* Output YYTOKNUM. */
  {
    int i;
    int *values = xnmalloc (ntokens, sizeof *values);
    for (i = 0; i < ntokens; ++i)
      values[i] = symbols[i]->user_token_number;
    muscle_insert_int_table ("toknum", values,
			     values[0], 1, ntokens);
    free (values);
  }
}


/*-------------------------------------------------------------.
| Prepare the muscles related to the rules: rhs, prhs, r1, r2, |
| rline, dprec, merger.                                        |
`-------------------------------------------------------------*/

static void
prepare_rules (void)
{
  rule_number r;
  unsigned int i = 0;
  item_number *rhs = xnmalloc (nritems, sizeof *rhs);
  unsigned int *prhs = xnmalloc (nrules, sizeof *prhs);
  unsigned int *rline = xnmalloc (nrules, sizeof *rline);
  symbol_number *r1 = xnmalloc (nrules, sizeof *r1);
  unsigned int *r2 = xnmalloc (nrules, sizeof *r2);
  int *dprec = xnmalloc (nrules, sizeof *dprec);
  int *merger = xnmalloc (nrules, sizeof *merger);

  for (r = 0; r < nrules; ++r)
    {
      item_number *rhsp = NULL;
      /* Index of rule R in RHS. */
      prhs[r] = i;
      /* RHS of the rule R. */
      for (rhsp = rules[r].rhs; *rhsp >= 0; ++rhsp)
	rhs[i++] = *rhsp;
      /* LHS of the rule R. */
      r1[r] = rules[r].lhs->number;
      /* Length of rule R's RHS. */
      r2[r] = i - prhs[r];
      /* Separator in RHS. */
      rhs[i++] = -1;
      /* Line where rule was defined. */
      rline[r] = rules[r].location.start.line;
      /* Dynamic precedence (GLR).  */
      dprec[r] = rules[r].dprec;
      /* Merger-function index (GLR).  */
      merger[r] = rules[r].merger;
    }
  if (i != nritems)
    abort ();

  muscle_insert_item_number_table ("rhs", rhs, ritem[0], 1, nritems);
  muscle_insert_unsigned_int_table ("prhs", prhs, 0, 0, nrules);
  muscle_insert_unsigned_int_table ("rline", rline, 0, 0, nrules);
  muscle_insert_symbol_number_table ("r1", r1, 0, 0, nrules);
  muscle_insert_unsigned_int_table ("r2", r2, 0, 0, nrules);
  muscle_insert_int_table ("dprec", dprec, 0, 0, nrules);
  muscle_insert_int_table ("merger", merger, 0, 0, nrules);

  MUSCLE_INSERT_INT ("rules_number", nrules);
  MUSCLE_INSERT_INT ("max_left_semantic_context", max_left_semantic_context);

  free (rhs);
  free (prhs);
  free (rline);
  free (r1);
  free (r2);
  free (dprec);
  free (merger);
}

/*--------------------------------------------.
| Prepare the muscles related to the states.  |
`--------------------------------------------*/

static void
prepare_states (void)
{
  state_number i;
  symbol_number *values = xnmalloc (nstates, sizeof *values);
  for (i = 0; i < nstates; ++i)
    values[i] = states[i]->accessing_symbol;
  muscle_insert_symbol_number_table ("stos", values,
				     0, 1, nstates);
  free (values);

  MUSCLE_INSERT_INT ("last", high);
  MUSCLE_INSERT_INT ("final_state_number", final_state->number);
  MUSCLE_INSERT_INT ("states_number", nstates);
}



/*---------------------------------.
| Output the user actions to OUT.  |
`---------------------------------*/

static void
user_actions_output (FILE *out)
{
  rule_number r;

  fputs ("m4_define([b4_actions], \n[[", out);
  for (r = 0; r < nrules; ++r)
    if (rules[r].action)
      {
	fprintf (out, "  case %d:\n", r + 1);

	fprintf (out, "]b4_syncline([[%d]], ",
		 rules[r].action_location.start.line);
	escaped_file_name_output (out, rules[r].action_location.start.file);
	fprintf (out, ")[\n");
	fprintf (out, "    %s\n    break;\n\n",
		 rules[r].action);
      }
  fputs ("]])\n\n", out);
}

/*--------------------------------------.
| Output the merge functions to OUT.   |
`--------------------------------------*/

static void
merger_output (FILE *out)
{
  int n;
  merger_list* p;

  fputs ("m4_define([b4_mergers], \n[[", out);
  for (n = 1, p = merge_functions; p != NULL; n += 1, p = p->next)
    {