/* Test file for mpfr_{mul,div}_2{ui,si}.
Copyright 1999, 2001-2004, 2006-2023 Free Software Foundation, Inc.
Contributed by the AriC and Caramba projects, INRIA.
This file is part of the GNU MPFR Library.
The GNU MPFR Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 3 of the License, or (at your
option) any later version.
The GNU MPFR Library 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 Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
#include "mpfr-test.h"
static const char * const val[] = {
"1.0001@100","4.0004000000000@102", "4.0004000000000@97",
"1.ABF012345@-100","6.afc048d140000@-98","6.afc048d140000@-103",
"F.FFFFFFFFF@10000","3.fffffffffc000@10003","3.fffffffffc000@9998",
"1.23456789ABCDEF@42","4.8d159e26af37c@44","4.8d159e26af37c@39",
"17@42","5.c000000000000@45","5.c000000000000@40",
"42@-17","1.0800000000000@-13","1.0800000000000@-18"
};
static int
test_mul (int i, int div, mpfr_ptr y, mpfr_srcptr x,
unsigned long int n, mpfr_rnd_t r)
{
return
i == 0 ? (div ? mpfr_div_2ui : mpfr_mul_2ui) (y, x, n, r) :
i == 1 ? (div ? mpfr_div_2si : mpfr_mul_2si) (y, x, n, r) :
i == 2 ? (div ? mpfr_mul_2si : mpfr_div_2si) (y, x, -n, r) :
(exit (1), 0);
}
static void
underflow (mpfr_exp_t e)
{
mpfr_t x, y, z1, z2;
mpfr_exp_t emin;
int i, k, s;
int prec;
int rnd;
int div;
int inex1, inex2;
unsigned int flags1, flags2;
/* Test mul_2si(x, e - k), div_2si(x, k - e) and div_2ui(x, k - e) with
* emin = e, x = s * (1 + i/16), i in { -1, 0, 1 }, s in { -1, 1 }, and
* k = 1 to 4, by comparing the result with the one of a simple division.
*/
emin = mpfr_get_emin ();
set_emin (e);
mpfr_inits2 (8, x, y, (mpfr_ptr) 0);
for (i = 15; i <= 17; i++)
for (s = 1; s >= -1; s -= 2)
{
inex1 = mpfr_set_si_2exp (x, s * i, -4, MPFR_RNDN);
MPFR_ASSERTN (inex1 == 0);
for (prec = 6; prec >= 3; prec -= 3)
{
mpfr_inits2 (prec, z1, z2, (mpfr_ptr) 0);
RND_LOOP_NO_RNDF (rnd)
for (k = 1; k <= 4; k++)
{
/* The following one is assumed to be correct. */
inex1 = mpfr_mul_2si (y, x, e, MPFR_RNDN);
MPFR_ASSERTN (inex1 == 0);
inex1 = mpfr_set_ui (z1, 1 << k, MPFR_RNDN);
MPFR_ASSERTN (inex1 == 0);
mpfr_clear_flags ();
/* Do not use mpfr_div_ui to avoid the optimization
by mpfr_div_2si. */
inex1 = mpfr_div (z1, y, z1, (mpfr_rnd_t) rnd);
flags1 = __gmpfr_flags;
for (div = 0; div <= 2; div++)
{
mpfr_clear_flags ();
inex2 =
div == 0 ?
mpfr_mul_2si (z2, x, e - k, (mpfr_rnd_t) rnd) :
div == 1 ?
mpfr_div_2si (z2, x, k - e, (mpfr_rnd_t) rnd) :
mpfr_div_2ui (z2, x, k - e, (mpfr_rnd_t) rnd);
flags2 = __gmpfr_flags;
if (flags1 == flags2 && SAME_SIGN (inex1, inex2) &&
mpfr_equal_p (z1, z2))
continue;
printf ("Error in underflow(");
if (e == MPFR_EMIN_MIN)
printf ("MPFR_EMIN_MIN");
else if (e == emin)
printf ("default emin");
else
printf ("%" MPFR_EXP_FSPEC "d", (mpfr_eexp_t) e);
printf (") with mpfr_%s,\nx = %d/16, prec = %d, k = %d,"
" %s\n", div == 0 ? "mul_2si" : div == 1 ?
"div_2si" : "div_2ui", s * i, prec, k,
mpfr_print_rnd_mode ((mpfr_rnd_t) rnd));
printf ("Expected ");
mpfr_out_str (stdout, 16, 0, z1, MPFR_RNDN);
printf (", inex = %d, flags = %u\n",
VSIGN (inex1), flags1);
printf ("Got ");
mpfr_out_str (stdout, 16, 0, z2, MPFR_RNDN);
printf (", inex = %d, flags = %u\n",
VSIGN (inex2), flags2);
exit (1);
} /* div */
} /* k */
mpfr_clears (z1, z2, (mpfr_ptr) 0);
} /* prec */
} /* i */
mpfr_clears (x, y, (mpfr_ptr) 0);
set_emin (emin);
}
static void
underflow0 (void)
{
underflow (-256);
if (mpfr_get_emin () != MPFR_EMIN_MIN)
underflow (mpfr_get_emin ());
underflow (MPFR_EMIN_MIN);
}
static void
large (mpfr_exp_t e)
{
mpfr_t x, y, z;
mpfr_exp_t emax;
int inex;
unsigned int flags;
emax = mpfr_get_emax ();
set_emax (e);
mpfr_init2 (x, 8);
mpfr_init2 (y, 8);
mpfr_init2 (z, 4);
mpfr_set_inf (x, 1);
mpfr_nextbelow (x);
mpfr_mul_2si (y, x, -1, MPFR_RNDU);
mpfr_prec_round (y, 4, MPFR_RNDU);
mpfr_clear_flags ();
inex = mpfr_mul_2si (z, x, -1, MPFR_RNDU);
flags = __gmpfr_flags;
if (inex <= 0 || flags != MPFR_FLAGS_INEXACT || ! mpfr_equal_p (y, z))
{
printf ("Error in large(");
if (e == MPFR_EMAX_MAX)
printf ("MPFR_EMAX_MAX");
else if (e == emax)
printf ("default emax");
else
printf ("%" MPFR_EXP_FSPEC "d", (mpfr_eexp_t) e);
printf (") for mpfr_mul_2si\n");
printf ("Expected inex > 0, flags = %u,\n y = ",
(unsigned int) MPFR_FLAGS_INEXACT);
mpfr_dump (y);
printf ("Got inex = %d, flags = %u,\n y = ",
inex, flags);
mpfr_dump (z);
exit (1);
}
mpfr_clear_flags ();
inex = mpfr_div_2si (z, x, 1, MPFR_RNDU);
flags = __gmpfr_flags;
if (inex <= 0 || flags != MPFR_FLAGS_INEXACT || ! mpfr_equal_p (y, z))
{
printf ("Error in large(");
if (e == MPFR_EMAX_MAX)
printf ("MPFR_EMAX_MAX");
else if (e == emax)
printf ("default emax");
else
printf ("%" MPFR_EXP_FSPEC "d", (mpfr_eexp_t) e);
printf (") for mpfr_div_2si\n");
printf ("Expected inex > 0, flags = %u,\n y = ",
(unsigned int) MPFR_FLAGS_INEXACT);
mpfr_dump (y);
printf ("Got inex = %d, flags = %u,\n y = ",
inex, flags);
mpfr_dump (z);
exit (1);
}
mpfr_clear_flags ();
inex = mpfr_div_2ui (z, x, 1, MPFR_RNDU);
flags = __gmpfr_flags;
if (inex <= 0 || flags != MPFR_FLAGS_INEXACT || ! mpfr_equal_p (y, z))
{
printf ("Error in large(");
if (e == MPFR_EMAX_MAX)
printf ("MPFR_EMAX_MAX");
else if (e == emax)
printf ("default emax");
else
printf ("%" MPFR_EXP_FSPEC "d", (mpfr_eexp_t) e);
printf (") for mpfr_div_2ui\n");
printf ("Expected inex > 0, flags = %u,\n y = ",
(unsigned int) MPFR_FLAGS_INEXACT);
mpfr_dump (y);
printf ("Got inex = %d, flags = %u,\n y = ",
inex, flags);
mpfr_dump (z);
exit (1);
}
mpfr_clears (x, y, z, (mpfr_ptr) 0);
set_emax (emax);
}
static void
large0 (void)
{
mpfr_exp_t emin;
emin = mpfr_get_emin ();
while (1)
{
large (256);
if (mpfr_get_emax () != MPFR_EMAX_MAX)
large (mpfr_get_emax ());
large (MPFR_EMAX_MAX);
if (mpfr_get_emin () == MPFR_EMIN_MIN)
break;
/* Redo the test with __gmpfr_emin set to MPFR_EMIN_MIN, which can
be useful to trigger integer overflows as in div_2ui.c r12272. */
set_emin (MPFR_EMIN_MIN);
}
set_emin (emin);
}
/* Cases where the function overflows on n = 0 when rounding is like
away from zero. */
static void
overflow0 (mpfr_exp_t emax)
{
mpfr_exp_t old_emax;
mpfr_t x, y1, y2;
int neg, r, op;
static const char *sop[4] = { "mul_2ui", "mul_2si", "div_2ui", "div_2si" };
old_emax = mpfr_get_emax ();
set_emax (emax);
mpfr_init2 (x, 8);
mpfr_inits2 (6, y1, y2, (mpfr_ptr) 0);
mpfr_set_inf (x, 1);
mpfr_nextbelow (x);
for (neg = 0; neg <= 1; neg++)
{
RND_LOOP_NO_RNDF (r)
{
int inex1, inex2;
mpfr_flags_t flags1, flags2;
/* Even if there isn't an overflow (rounding ~ toward zero),
the result is the same as the one of an overflow. */
inex1 = mpfr_overflow (y1, (mpfr_rnd_t) r, neg ? -1 : 1);
flags1 = MPFR_FLAGS_INEXACT;
if (mpfr_inf_p (y1))
flags1 |= MPFR_FLAGS_OVERFLOW;
for (op = 0; op < 4; op++)
{
mpfr_clear_flags ();
inex2 =
op == 0 ? mpfr_mul_2ui (y2, x, 0, (mpfr_rnd_t) r) :
op == 1 ? mpfr_mul_2si (y2, x, 0, (mpfr_rnd_t) r) :
op == 2 ? mpfr_div_2ui (y2, x, 0, (mpfr_rnd_t) r) :
op == 3 ? mpfr_div_2si (y2, x, 0, (mpfr_rnd_t) r) :
(MPFR_ASSERTN (0), 0);
flags2 = __gmpfr_flags;
if (!(mpfr_equal_p (y1, y2) &&
SAME_SIGN (inex1, inex2) &&
flags1 == flags2))
{
printf ("Error in overflow0 for %s, mpfr_%s, emax = %"
MPFR_EXP_FSPEC "d,\nx = ",
mpfr_print_rnd_mode ((mpfr_rnd_t) r), sop[op],
(mpfr_eexp_t) emax);
mpfr_dump (x);
printf ("Expected ");
mpfr_dump (y1);
printf (" with inex = %d, flags =", inex1);
flags_out (flags1);
printf ("Got ");
mpfr_dump (y2);
printf (" with inex = %d, flags =", inex2);
flags_out (flags2);
exit (1);
}
}
}
mpfr_neg (x, x, MPFR_RNDN);
}
mpfr_clears (x, y1, y2, (mpfr_ptr) 0);
set_emax (old_emax);
}
static void
coverage_div_2ui (void)
{
mpfr_t x, y;
mpfr_init2 (x, 2);
mpfr_init2 (y, 2);
mpfr_set_ui_2exp (x, 1, mpfr_get_emax () - 1, MPFR_RNDN);
mpfr_div_2ui (y, x, (unsigned long) LONG_MAX + 1, MPFR_RNDN);
MPFR_ASSERTN(mpfr_zero_p (y));
MPFR_ASSERTN(mpfr_signbit (y) == 0);
mpfr_clear (x);
mpfr_clear (y);
}
int
main (int argc, char *argv[])
{
mpfr_t w,z;
unsigned long k;
int i;
tests_start_mpfr ();
coverage_div_2ui ();
mpfr_inits2 (53, w, z, (mpfr_ptr) 0);
for (i = 0; i < 3; i++)
{
mpfr_set_inf (w, 1);
test_mul (i, 0, w, w, 10, MPFR_RNDZ);
if (!MPFR_IS_INF(w))
{
printf ("Result is not Inf (i = %d)\n", i);
exit (1);
}
mpfr_set_nan (w);
test_mul (i, 0, w, w, 10, MPFR_RNDZ);
if (!MPFR_IS_NAN(w))
{
printf ("Result is not NaN (i = %d)\n", i);
exit (1);
}
for (k = 0 ; k < numberof(val) ; k+=3)
{
mpfr_set_str (w, val[k], 16, MPFR_RNDN);
test_mul (i, 0, z, w, 10, MPFR_RNDZ);
if (mpfr_cmp_str (z, val[k+1], 16, MPFR_RNDN))
{
printf ("ERROR for x * 2^n (i = %d) for %s\n", i, val[k]);
printf ("Expected: %s\n"
"Got : ", val[k+1]);
mpfr_out_str (stdout, 16, 0, z, MPFR_RNDN);
putchar ('\n');
exit (1);
}
test_mul (i, 1, z, w, 10, MPFR_RNDZ);
if (mpfr_cmp_str (z, val[k+2], 16, MPFR_RNDN))
{
printf ("ERROR for x / 2^n (i = %d) for %s\n", i, val[k]);
printf ("Expected: %s\n"
"Got : ", val[k+2]);
mpfr_out_str (stdout, 16, 0, z, MPFR_RNDN);
putchar ('\n');
exit (1);
}
}
mpfr_set_inf (w, 1);
mpfr_nextbelow (w);
test_mul (i, 0, w, w, 1, MPFR_RNDN);
if (!mpfr_inf_p (w))
{
printf ("Overflow error (i = %d)!\n", i);
exit (1);
}
mpfr_set_ui (w, 0, MPFR_RNDN);
mpfr_nextabove (w);
test_mul (i, 1, w, w, 1, MPFR_RNDN);
if (mpfr_cmp_ui (w, 0))
{
printf ("Underflow error (i = %d)!\n", i);
exit (1);
}
}
if (MPFR_EXP_MAX >= LONG_MAX/2 && MPFR_EXP_MIN <= LONG_MAX/2-LONG_MAX-1)
{
unsigned long lmp1 = (unsigned long) LONG_MAX + 1;
mpfr_set_ui (w, 1, MPFR_RNDN);
mpfr_mul_2ui (w, w, LONG_MAX/2, MPFR_RNDZ);
mpfr_div_2ui (w, w, lmp1, MPFR_RNDZ);
mpfr_mul_2ui (w, w, lmp1 - LONG_MAX/2, MPFR_RNDZ);
if (!mpfr_cmp_ui (w, 1))
{
printf ("Underflow LONG_MAX error!\n");
exit (1);
}
}
mpfr_clears (w, z, (mpfr_ptr) 0);
underflow0 ();
large0 ();
if (mpfr_get_emax () != MPFR_EMAX_MAX)
overflow0 (mpfr_get_emax ());
overflow0 (MPFR_EMAX_MAX);
overflow0 (-1);
tests_end_mpfr ();
return 0;
}