math/gfreduce.[ch]: Fix out-of-bounds memory access.

[u/mdw/catacomb] / math / genlimits.c

/* -*-c-*-
 *
 * Generate limit MPs for C types
 *
 * (c) 2006 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------*
 *
 * This file is part of Catacomb.
 *
 * Catacomb is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Library General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * Catacomb 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 Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with Catacomb; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 */

/*----- Header files ------------------------------------------------------*/

#define _GNU_SOURCE
#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <string.h>

#if __STDC_VERSION__ >= 199900l
#  include <stdint.h>
#  include <inttypes.h>
#endif

#include "mp.h"
#include "mpint.h"

/*----- Data types --------------------------------------------------------*/

/* --- Hack for GCC --- *
 *
 * WG14 in their infinite wisdom decided not to use the GCC constant name.
 */

#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 91)
#  define EXT __extension__
#else
#  define EXT
#endif

#if defined(LONG_LONG_MIN) && !defined(LLONG_MIN)
#  define LLONG_MIN EXT LONG_LONG_MIN
#endif

#if defined(LONG_LONG_MAX) && !defined(LLONG_MAX)
#  define LLONG_MAX EXT LONG_LONG_MAX
#endif

#if defined(ULONG_LONG_MAX) && !defined(ULLONG_MAX)
#  define ULLONG_MAX EXT ULONG_LONG_MAX
#endif

/* --- Choose the largest integer type --- */

#if defined(INTMAX_MAX)
  typedef intmax_t imax;
#elif defined(LLONG_MAX)
  EXT typedef long long imax;
#else
  typedef long imax;
#endif

#if defined(UINTMAX_MAX)
  typedef uintmax_t umax;
#elif defined(ULLONG_MAX)
  EXT typedef unsigned long long umax;
#else
  typedef unsigned long umax;
#endif

/*----- Main code ---------------------------------------------------------*/

#define TABSZ 64

enum { NEG, POS, NSIGN };

umax cmap[TABSZ];
int gmap[TABSZ][NSIGN];
struct { int g, s; } qmap[TABSZ];
int dumpp = 0;

static int n, q;

static void dump(mp *x)
{
  int i, w, n;

  fputs("  ", stdout);
  w = (MPW_BITS + 3)/4;
  n = 1;
  while (2 + 2 * n * (4 + w) < 72) n <<= 1;
  i = 0;
  for (;;) {
    printf("0x%0*x", w, x->v[i]);
    i++;
    if (i >= MP_LEN(x)) break;
    fputs(",", stdout);
    if (i % n) fputs(" ", stdout); else fputs("\n  ", stdout);
  }
  fputs("\n", stdout);
}

static void doemit(umax c, int s, int *gg, int *qq)
{
  int i;
  mp *x = MP_NEW;

  for (i = 0; i < n; i++) {
    if (cmap[i] == c)
      goto found;
  }

  assert(i < TABSZ);
  n = i + 1;
  cmap[i] = c;
  gmap[i][POS] = gmap[i][NEG] = -1;
  if (dumpp) {
    MP_FROMINT(x, umax, c);
    printf("static mpw guts_%d[] = {\n", q);
    dump(x);
    fputs("};\n\n", stdout);
    MP_DROP(x);
  }

found:
  *gg = i;
  if (gmap[i][s] < 0) {
    assert(q < TABSZ);
    gmap[i][s] = q;
    qmap[q].g = i;
    qmap[q].s = s;
    q++;
  }
  *qq = gmap[i][s];
}

static void emit(imax c, int *gg, int *qq)
{
  umax uc;
  int s;

  if (c >= 0) { uc = c; s = POS; }
  else { uc = -c; s = NEG; }
  doemit(uc, s, gg, qq);
}

static void uemit(umax c, int *gg, int *qq) { doemit(c, POS, gg, qq); }

struct {
  const char *name;
  imax min;
  umax max;
  int gmin, gmax;
  int qmin, qmax;
} tab[] = {
  { "SCHAR",	SCHAR_MIN,	SCHAR_MAX },
  { "CHAR",	CHAR_MIN,	CHAR_MAX },
  { "UCHAR",	0,		UCHAR_MAX },
  { "UINT8",	0,		0xff },
  { "SHRT",	SHRT_MIN,	SHRT_MAX },
  { "USHRT",	0,		USHRT_MAX },
  { "UINT16",	0,		0xffff },
  { "INT",	INT_MIN,	INT_MAX },
  { "UINT",	0,		UINT_MAX },
  { "LONG",	LONG_MIN,	LONG_MAX },
  { "ULONG",	0,		ULONG_MAX },
  { "UINT32",	0,		0xffffffff },
#ifdef LLONG_MAX
  { "LLONG",	LLONG_MIN,	LLONG_MAX },
  { "ULLONG",	0,		ULLONG_MAX },
#endif
  { "SIZET",	0,		~(size_t)0 },
  { 0 }
};

static void dogen(void)
{
  int i;

  for (i = 0; tab[i].name; i++) {
    if (tab[i].min)
      emit(tab[i].min, &tab[i].gmin, &tab[i].qmin);
    uemit(tab[i].max, &tab[i].gmax, &tab[i].qmax);
  }
}

static void cgen(void)
{
  int i;

  fputs("\
/* -*-c-*-\n\
 *\n\
 * C integer limits [generated]\n\
 */\n\
\n\
#include \"mplimits.h\"\n\
\n\
#define N(x) (sizeof(x)/sizeof(*x))\n\
#define MPpos(x) { x, x + N(x), N(x), 0, MP_CONST, 0 }\n\
#define MPneg(x) { x, x + N(x), N(x), 0, MP_CONST|MP_NEG, 0 }\n\
\n",
	stdout);
  dumpp = 1;
  dogen();

  fputs("mp mp_limits[] = {\n", stdout);
  for (i = 0; i < q; i++)
    printf("  MP%s(guts_%d),\n", qmap[i].s ? "pos" : "neg", qmap[i].g);
  fputs("};\n", stdout);
}

static void hgen(void)
{
  int i;

  fputs("\
/* -*-c-*-\n\
 *\n\
 * C integer limits [generated]\n\
 */\n\
\n\
#ifndef CATACOMB_MPLIMITS_H\n\
#define CATACOMB_MPLIMITS_H\n\
\n\
#ifndef CATACOMB_MP_H\n\
#  include \"mp.h\"\n\
#endif\n\
\n\
extern mp mp_limits[];\n\
\n",
	stdout);
  dogen();

  for (i = 0; tab[i].name; i++) {
    if (tab[i].min) {
      printf("#define MP_%s_MIN (&mp_limits[%d])\n",
	     tab[i].name, gmap[tab[i].qmin][NEG]);
    }
    printf("#define MP_%s_MAX (&mp_limits[%d])\n",
	   tab[i].name, gmap[tab[i].qmax][POS]);
  }
  fputs("\n#endif\n", stdout);
}

int main(int argc, char *argv[])
{
  const char *what = argc == 2 ? argv[1] : "<bogus>";

  switch (what[0]) {
    case 'c': cgen(); break;
    case 'h': hgen(); break;
    default:
      fprintf(stderr, "unknown action `%s'\n", what);
      exit(1);
  }
  if (fflush(stdout) || fclose(stdout)) {
    fprintf(stderr, "error writing output: %s\n", strerror(errno));
    exit(1);
  }
  return (0);
}

/*----- That's all, folks -------------------------------------------------*/