gengenrtl.c

/* Generate code to allocate RTL structures.
   Copyright (C) 1997, 1998, 1999, 2000, 2002, 2003, 2004, 2007, 2010
   Free Software Foundation, Inc.

This file is part of GCC.

GCC 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, or (at your option) any later
version.

GCC 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 GCC; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  */


#include "bconfig.h"
#include "system.h"

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

/* rtl.def needs CONST_DOUBLE_FORMAT, but we don't care what
   CONST_DOUBLE_FORMAT is because we're not going to be generating
   anything for CONST_DOUBLE anyway.  */
#define CONST_DOUBLE_FORMAT ""

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

static const struct rtx_definition defs[] =
{
#include "rtl.def"		/* rtl expressions are documented here */
};
#define NUM_RTX_CODE ARRAY_SIZE(defs)

static const char *formats[NUM_RTX_CODE];

/* Decode a format letter into a C type string.  */

static const char *
type_from_format (int c)
{
  switch (c)
    {
    case 'i':
      return "int ";

    case 'w':
      return "HOST_WIDE_INT ";

    case 's':
      return "const char *";

    case 'e':  case 'u':
      return "rtx ";

    case 'E':
      return "rtvec ";
    case 't':
      return "union tree_node *";  /* tree - typedef not available */
    case 'B':
      return "struct basic_block_def *";  /* basic block - typedef not available */
    default:
      gcc_unreachable ();
    }
}

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

static const char *
accessor_from_format (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 't':
      return "XTREE";

    case 'B':
      return "XBBDEF";

    default:
      gcc_unreachable ();
    }
}

/* Return nonzero if we should ignore FMT, an RTL format, when making
   the list of formats we write routines to create.  */

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

/* Return nonzero if the RTL code given by index IDX is one that we should
   generate a gen_rtx_raw_FOO macro for, not gen_rtx_FOO (because gen_rtx_FOO
   is a wrapper in emit-rtl.c).  */

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

/* Return nonzero if the RTL code given by index IDX is one that we should
   generate no macro for at all (because gen_rtx_FOO is never used or
   cannot have the obvious interface).  */

static int
excluded_rtx (int idx)
{
  return ((strcmp (defs[idx].enumname, "CONST_DOUBLE") == 0)
	  || (strcmp (defs[idx].enumname, "CONST_FIXED") == 0));
}

/* Place a list of all format specifiers we use into the array FORMAT.  */

static void
find_formats (void)
{
  unsigned 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 == 0)
	*f = defs[i].format;
    }
}


/* Generate macros to generate RTL of code IDX using the functions we
   write.  */

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

  /* We write a macro that defines gen_rtx_RTLCODE to be an equivalent to
     gen_rtx_fmt_FORMAT where FORMAT is the RTX_FORMAT of RTLCODE.  */

  if (excluded_rtx (idx))
    /* Don't define a macro for this code.  */
    return;

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

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

  printf (") \\\n  gen_rtx_fmt_%s (%s, (MODE)",
	  defs[idx].format, defs[idx].enumname);

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

  puts (")");
}

/* Generate the code for the function to generate RTL whose
   format is FORMAT.  */

static void
gendef (const char *format)
{
  const char *p;
  int i, j;

  /* Start by writing the definition of the function name and the types
     of the arguments.  */

  printf ("static inline rtx\ngen_rtx_fmt_%s_stat (RTX_CODE code, enum machine_mode mode", format);
  for (p = format, i = 0; *p != 0; p++)
    if (*p != '0')
      printf (",\n\t%sarg%d", type_from_format (*p), i++);

  puts (" MEM_STAT_DECL)");

  /* Now write out the body of the function itself, which allocates
     the memory and initializes it.  */
  puts ("{");
  puts ("  rtx rt;");
  puts ("  rt = rtx_alloc_stat (code PASS_MEM_STAT);\n");

  puts ("  PUT_MODE (rt, mode);");

  for (p = format, i = j = 0; *p ; ++p, ++i)
    if (*p != '0')
      printf ("  %s (rt, %d) = arg%d;\n", accessor_from_format (*p), i, j++);
    else
      printf ("  X0EXP (rt, %d) = NULL_RTX;\n", i);

  puts ("\n  return rt;\n}\n");
  printf ("#define gen_rtx_fmt_%s(c, m", format);
  for (p = format, i = 0; *p != 0; p++)
    if (*p != '0')
      printf (", p%i",i++);
  printf (")\\\n        gen_rtx_fmt_%s_stat (c, m", format);
  for (p = format, i = 0; *p != 0; p++)
    if (*p != '0')
      printf (", p%i",i++);
  printf (" MEM_STAT_INFO)\n\n");
}

/* Generate the documentation header for files we write.  */

static void
genlegend (void)
{
  puts ("/* Generated automatically by gengenrtl from rtl.def.  */\n");
}

/* Generate the text of the header file we make, genrtl.h.  */

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

  puts ("#ifndef GCC_GENRTL_H");
  puts ("#define GCC_GENRTL_H\n");
  puts ("#include \"statistics.h\"\n");

  for (fmt = formats; *fmt; ++fmt)
    gendef (*fmt);

  putchar ('\n');

  for (i = 0; i < NUM_RTX_CODE; i++)
    if (! special_format (defs[i].format))
      genmacro (i);

  puts ("\n#endif /* GCC_GENRTL_H */");
}

/* This is the main program.  */

int
main (void)
{
  find_formats ();
  genlegend ();

  genheader ();

  if (ferror (stdout) || fflush (stdout) || fclose (stdout))
    return FATAL_EXIT_CODE;

  return SUCCESS_EXIT_CODE;
}