/* Generate code to allocate RTL structures.
   Copyright (C) 1997, 1998, 1999 Free Software Foundation, Inc.

This file is part of GNU CC.

GNU CC 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.

GNU CC 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 GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */


#include "hconfig.h"
#include "system.h"

#define NO_GENRTL_H
#include "rtl.h"
#undef abort

#include "real.h"

/* Calculate the format for CONST_DOUBLE.  This depends on the relative
   widths of HOST_WIDE_INT and REAL_VALUE_TYPE.
   We only need to go out to e0wwww, since min(HOST_WIDE_INT)==32 and
   max(LONG_DOUBLE_TYPE_SIZE)==128.
   This is duplicated in rtl.c.  
   A number of places assume that there are always at least two 'w'
   slots in a CONST_DOUBLE, so we provide them even if one would suffice.  */
#if HOST_BITS_PER_WIDE_INT >= LONG_DOUBLE_TYPE_SIZE
#define CONST_DOUBLE_FORMAT	"e0ww"
#elif HOST_BITS_PER_WIDE_INT*2 >= LONG_DOUBLE_TYPE_SIZE
#define CONST_DOUBLE_FORMAT	"e0ww"
#elif HOST_BITS_PER_WIDE_INT*3 >= LONG_DOUBLE_TYPE_SIZE
#define CONST_DOUBLE_FORMAT	"e0www"
#elif HOST_BITS_PER_WIDE_INT*4 >= LONG_DOUBLE_TYPE_SIZE
#define CONST_DOUBLE_FORMAT	"e0wwww"
#else
#define CONST_DOUBLE_FORMAT	/* nothing - will cause syntax error */
#endif


struct rtx_definition 
{
  const char *enumname, *name, *format;
};

#define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) { STRINGIFY(ENUM), NAME, FORMAT },

struct rtx_definition defs[] = 
{  
#include "rtl.def"		/* rtl expressions are documented here */
};

const char *formats[NUM_RTX_CODE];

static const char *type_from_format PROTO((int));
static const char *accessor_from_format PROTO((int));
static int special_format PROTO((const char *));
static int special_rtx PROTO((int));
static void find_formats PROTO((void));
static void gendecl PROTO((FILE *, const char *));
static void genmacro PROTO((FILE *, int));
static void gendef PROTO((FILE *, const char *));
static void genlegend PROTO((FILE *));
static void genheader PROTO((FILE *));
static void gencode PROTO((FILE *));

/* Decode a format letter into a C type string.  */

static const char *
type_from_format (c)
     int c;
{
  switch (c)
    {
    case 'i':
      return "int";
    case 'w':
      return "HOST_WIDE_INT";
    case 's':
      return "char *";
    case 'e':
    case 'u':
      return "rtx";
    case 'E':
      return "rtvec";
    case 'b':
      return "struct bitmap_head_def *";  /* bitmap - typedef not available */
    case 't':
      return "union tree_node *";  /* tree - typedef not available */
    default:
      abort ();
    }
}

/* Decode a format letter into the proper accessor function.  */

static const char *
accessor_from_format (c)
     int c;
{
  switch (c)
    {
    case 'i':
      return "XINT";
    case 'w':
      return "XWINT";
    case 's':
      return "XSTR";
    case 'e':
    case 'u':
      return "XEXP";
    case 'E':
      return "XVEC";
    case 'b':
      return "XBITMAP";
    case 't':
      return "XTREE";
    default:
      abort ();
    }
}

/* Return true if a format character doesn't need normal processing.  */

static int
special_format (fmt)
     const char *fmt;
{
  return (strchr (fmt, '*') != 0
	  || strchr (fmt, 'V') != 0
	  || strchr (fmt, 'S') != 0
	  || strchr (fmt, 'n') != 0);
}

/* Return true if an rtx requires special processing.  */

static int
special_rtx (idx)
     int idx;
{
  return (strcmp (defs[idx].enumname, "CONST_INT") == 0
	  || strcmp (defs[idx].enumname, "CONST_DOUBLE") == 0
	  || strcmp (defs[idx].enumname, "REG") == 0
	  || strcmp (defs[idx].enumname, "MEM") == 0);
}

/* Fill `formats' with all unique format strings.  */

static void
find_formats ()
{
  int i;

  for (i = 0; i < NUM_RTX_CODE; ++i)
    {
      const char **f;

      if (special_format (defs[i].format))
	continue;

      for (f = formats; *f ; ++f)
	if (! strcmp (*f, defs[i].format))
	  break;

      if (!*f)
	*f = defs[i].format;
    }
}

/* Emit a prototype for the rtx generator for a format.  */

static void
gendecl (f, format)
     FILE *f;
     const char *format;
{
  const char *p;
  int i;
  
  fprintf (f, "extern rtx gen_rtx_fmt_%s PROTO((RTX_CODE, enum machine_mode mode",
	   format);
  for (p = format, i = 0; *p ; ++p)
    if (*p != '0')
      fprintf (f, ", %s arg%d", type_from_format (*p), i++);
  fprintf (f, "));\n");
}

/* Emit a define mapping an rtx code to the generator for its format.  */

static void 
genmacro (f, idx)
     FILE *f;
     int idx;
{
  const char *p;
  int i;

  fprintf (f, "#define gen_rtx_%s%s(mode",
	   (special_rtx (idx) ? "raw_" : ""), defs[idx].enumname);

  for (p = defs[idx].format, i = 0; *p ; ++p)
    if (*p != '0')
      fprintf (f, ", arg%d", i++);
  fprintf (f, ")   ");

  fprintf (f, "gen_rtx_fmt_%s(%s,(mode)", defs[idx].format, defs[idx].enumname);
  for (p = defs[idx].format, i = 0; *p ; ++p)
    if (*p != '0')
      fprintf (f, ",(arg%d)", i++);
  fprintf (f, ")\n");
}

/* Emit the implementation for the rtx generator for a format.  */

static void
gendef (f, format)
     FILE *f;
     const char *format;
{
  const char *p;
  int i, j;
  
  fprintf (f, "rtx\ngen_rtx_fmt_%s (code, mode", format);
  for (p = format, i = 0; *p ; ++p)
    if (*p != '0')
      fprintf (f, ", arg%d", i++);

  fprintf (f, ")\n     RTX_CODE code;\n     enum machine_mode mode;\n");
  for (p = format, i = 0; *p ; ++p)
    if (*p != '0')
      fprintf (f, "     %s arg%d;\n", type_from_format (*p), i++);

  /* See rtx_alloc in rtl.c for comments.  */
  fprintf (f, "{\n");
  fprintf (f, "  rtx rt = obstack_alloc_rtx (sizeof (struct rtx_def) + %d * sizeof (rtunion));\n",
	   (int) strlen (format) - 1);

  fprintf (f, "  PUT_CODE (rt, code);\n");
  fprintf (f, "  PUT_MODE (rt, mode);\n");

  for (p = format, i = j = 0; *p ; ++p, ++i)
    if (*p != '0')
      {
	fprintf (f, "  %s (rt, %d) = arg%d;\n",
		 accessor_from_format (*p), i, j++);
      }

  fprintf (f, "\n  return rt;\n}\n\n");
}

/* Emit the `do not edit' banner.  */

static void
genlegend (f)
     FILE *f;
{
  fputs ("/* Generated automaticaly by the program `gengenrtl'\n", f);
  fputs ("   from the RTL description file `rtl.def' */\n\n", f);
}

/* Emit "genrtl.h".  */

static void
genheader (f)
     FILE *f;
{
  int i;
  const char **fmt;

  for (fmt = formats; *fmt; ++fmt)
    gendecl (f, *fmt);

  fprintf (f, "\n");

  for (i = 0; i < NUM_RTX_CODE; i++)
    {
      if (special_format (defs[i].format))
	continue;
      genmacro (f, i);
    }
}

/* Emit "genrtl.c".  */

static void
gencode (f)
     FILE *f;
{
  const char **fmt;

  fputs ("#include \"config.h\"\n", f);
  fputs ("#include \"system.h\"\n", f);
  fputs ("#include \"obstack.h\"\n", f);
  fputs ("#include \"rtl.h\"\n\n", f);
  fputs ("extern struct obstack *rtl_obstack;\n\n", f);
  fputs ("static rtx obstack_alloc_rtx PROTO((int length));\n", f);
  fputs ("static rtx obstack_alloc_rtx (length)\n", f);
  fputs ("     register int length;\n{\n", f);
  fputs ("  rtx rt = (rtx) obstack_alloc (rtl_obstack, length);\n\n", f);
  fputs ("  memset(rt, 0, sizeof(struct rtx_def) - sizeof(rtunion));\n\n", f);
  fputs ("  return rt;\n}\n\n", f);

  for (fmt = formats; *fmt; ++fmt)
    gendef (f, *fmt);
}

#if defined(USE_C_ALLOCA)
PTR
xmalloc (nbytes)
  size_t nbytes;
{
  register PTR tmp = (PTR) malloc (nbytes);

  if (!tmp)
    {
      fprintf (stderr, "can't allocate %d bytes (out of virtual memory)\n",
	       nbytes);
      exit (FATAL_EXIT_CODE);
    }

  return tmp;
}
#endif /* USE_C_ALLOCA */

int
main(argc, argv)
     int argc;
     char **argv;
{
  FILE *f;

  if (argc != 3)
    exit (1);

  find_formats ();

  f = fopen (argv[1], "w");
  if (f == NULL)
    {
      perror (argv[1]);
      exit (1);
    }
  genlegend (f);
  genheader (f);
  fclose (f);

  f = fopen (argv[2], "w");
  if (f == NULL)
    {
      perror (argv[2]);
      exit (1);
    }
  genlegend (f);
  gencode (f);
  fclose (f);

  exit (0);
}
