/* Test file for mpfr_ui_sub.
Copyright 2000-2018 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
http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
#include <float.h>
#include "mpfr-test.h"
static void
special (void)
{
mpfr_t x, y, res;
int inexact;
mpfr_init (x);
mpfr_init (y);
mpfr_init (res);
mpfr_set_prec (x, 24);
mpfr_set_prec (y, 24);
mpfr_set_str_binary (y, "0.111100110001011010111");
inexact = mpfr_ui_sub (x, 1, y, MPFR_RNDN);
if (inexact)
{
printf ("Wrong inexact flag: got %d, expected 0\n", inexact);
exit (1);
}
mpfr_set_prec (x, 24);
mpfr_set_prec (y, 24);
mpfr_set_str_binary (y, "0.111100110001011010111");
if ((inexact = mpfr_ui_sub (x, 38181761, y, MPFR_RNDN)) >= 0)
{
printf ("Wrong inexact flag: got %d, expected -1\n", inexact);
exit (1);
}
mpfr_set_prec (x, 63);
mpfr_set_prec (y, 63);
mpfr_set_str_binary (y, "0.111110010010100100110101101010001001100101110001000101110111111E-1");
if ((inexact = mpfr_ui_sub (x, 1541116494, y, MPFR_RNDN)) <= 0)
{
printf ("Wrong inexact flag: got %d, expected +1\n", inexact);
exit (1);
}
mpfr_set_prec (x, 32);
mpfr_set_prec (y, 32);
mpfr_set_str_binary (y, "0.11011000110111010001011100011100E-1");
if ((inexact = mpfr_ui_sub (x, 2000375416, y, MPFR_RNDN)) >= 0)
{
printf ("Wrong inexact flag: got %d, expected -1\n", inexact);
exit (1);
}
mpfr_set_prec (x, 24);
mpfr_set_prec (y, 24);
mpfr_set_str_binary (y, "0.110011011001010011110111E-2");
if ((inexact = mpfr_ui_sub (x, 927694848, y, MPFR_RNDN)) <= 0)
{
printf ("Wrong inexact flag: got %d, expected +1\n", inexact);
exit (1);
}
/* bug found by Mathieu Dutour, 12 Apr 2001 */
mpfr_set_prec (x, 5);
mpfr_set_prec (y, 5);
mpfr_set_prec (res, 5);
mpfr_set_str_binary (x, "1e-12");
mpfr_ui_sub (y, 1, x, MPFR_RNDD);
mpfr_set_str_binary (res, "0.11111");
if (mpfr_cmp (y, res))
{
printf ("Error in mpfr_ui_sub (y, 1, x, MPFR_RNDD) for x=2^(-12)\nexpected 1.1111e-1, got ");
mpfr_out_str (stdout, 2, 0, y, MPFR_RNDN);
printf ("\n");
exit (1);
}
mpfr_ui_sub (y, 1, x, MPFR_RNDU);
mpfr_set_str_binary (res, "1.0");
if (mpfr_cmp (y, res))
{
printf ("Error in mpfr_ui_sub (y, 1, x, MPFR_RNDU) for x=2^(-12)\n"
"expected 1.0, got ");
mpfr_out_str (stdout, 2, 0, y, MPFR_RNDN);
printf ("\n");
exit (1);
}
mpfr_ui_sub (y, 1, x, MPFR_RNDN);
mpfr_set_str_binary (res, "1.0");
if (mpfr_cmp (y, res))
{
printf ("Error in mpfr_ui_sub (y, 1, x, MPFR_RNDN) for x=2^(-12)\n"
"expected 1.0, got ");
mpfr_out_str (stdout, 2, 0, y, MPFR_RNDN);
printf ("\n");
exit (1);
}
mpfr_set_prec (x, 10);
mpfr_set_prec (y, 10);
mpfr_urandomb (x, RANDS);
mpfr_ui_sub (y, 0, x, MPFR_RNDN);
if (MPFR_IS_ZERO(x))
MPFR_ASSERTN(MPFR_IS_ZERO(y));
else
MPFR_ASSERTN(mpfr_cmpabs (x, y) == 0 && mpfr_sgn (x) != mpfr_sgn (y));
mpfr_set_prec (x, 73);
mpfr_set_str_binary (x, "0.1101111010101011011011100011010000000101110001011111001011011000101111101E-99");
mpfr_ui_sub (x, 1, x, MPFR_RNDZ);
mpfr_nextabove (x);
MPFR_ASSERTN(mpfr_cmp_ui (x, 1) == 0);
mpfr_clear (x);
mpfr_clear (y);
mpfr_clear (res);
}
/* checks that (y-x) gives the right results with 53 bits of precision */
static void
check (unsigned long y, const char *xs, mpfr_rnd_t rnd_mode, const char *zs)
{
mpfr_t xx, zz;
mpfr_inits2 (53, xx, zz, (mpfr_ptr) 0);
mpfr_set_str1 (xx, xs);
mpfr_ui_sub (zz, y, xx, rnd_mode);
if (mpfr_cmp_str1 (zz, zs) )
{
printf ("expected difference is %s, got\n",zs);
mpfr_out_str(stdout, 10, 0, zz, MPFR_RNDN);
printf ("mpfr_ui_sub failed for y=%lu x=%s with rnd_mode=%s\n",
y, xs, mpfr_print_rnd_mode (rnd_mode));
exit (1);
}
mpfr_clears (xx, zz, (mpfr_ptr) 0);
}
/* if u = o(x-y), v = o(u-x), w = o(v+y), then x-y = u-w */
static void
check_two_sum (mpfr_prec_t p)
{
unsigned int x;
mpfr_t y, u, v, w;
mpfr_rnd_t rnd;
int inexact, cmp;
mpfr_inits2 (p, y, u, v, w, (mpfr_ptr) 0);
do
{
x = randlimb ();
}
while (x < 1);
mpfr_urandomb (y, RANDS);
rnd = MPFR_RNDN;
inexact = mpfr_ui_sub (u, x, y, rnd);
mpfr_sub_ui (v, u, x, rnd);
mpfr_add (w, v, y, rnd);
cmp = mpfr_cmp_ui (w, 0);
/* as u = (x-y) + w, we should have inexact and w of same sign */
if (! SAME_SIGN (inexact, cmp))
{
printf ("Wrong inexact flag for prec=%u, rnd=%s\n",
(unsigned int) p, mpfr_print_rnd_mode (rnd));
printf ("x = %u\n", x);
printf ("y = "); mpfr_dump (y);
printf ("u = "); mpfr_dump (u);
printf ("v = "); mpfr_dump (v);
printf ("w = "); mpfr_dump (w);
printf ("inexact = %d\n", inexact);
exit (1);
}
mpfr_clears (y, u, v, w, (mpfr_ptr) 0);
}
static void
check_nans (void)
{
mpfr_t x, y;
mpfr_init2 (x, 123L);
mpfr_init2 (y, 123L);
/* 1 - nan == nan */
mpfr_set_nan (x);
mpfr_ui_sub (y, 1L, x, MPFR_RNDN);
MPFR_ASSERTN (mpfr_nan_p (y));
/* 1 - +inf == -inf */
mpfr_set_inf (x, 1);
mpfr_ui_sub (y, 1L, x, MPFR_RNDN);
MPFR_ASSERTN (mpfr_inf_p (y));
MPFR_ASSERTN (mpfr_sgn (y) < 0);
/* 1 - -inf == +inf */
mpfr_set_inf (x, -1);
mpfr_ui_sub (y, 1L, x, MPFR_RNDN);
MPFR_ASSERTN (mpfr_inf_p (y));
MPFR_ASSERTN (mpfr_sgn (y) > 0);
mpfr_clear (x);
mpfr_clear (y);
}
/* Check mpfr_ui_sub with u = 0 (unsigned). */
static void check_neg (void)
{
mpfr_t x, yneg, ysub;
int i, s;
int r;
mpfr_init2 (x, 64);
mpfr_init2 (yneg, 32);
mpfr_init2 (ysub, 32);
for (i = 0; i <= 25; i++)
{
mpfr_sqrt_ui (x, i, MPFR_RNDN);
for (s = 0; s <= 1; s++)
{
RND_LOOP (r)
{
int tneg, tsub;
tneg = mpfr_neg (yneg, x, (mpfr_rnd_t) r);
tsub = mpfr_ui_sub (ysub, 0, x, (mpfr_rnd_t) r);
MPFR_ASSERTN (mpfr_equal_p (yneg, ysub));
MPFR_ASSERTN (!(MPFR_IS_POS (yneg) ^ MPFR_IS_POS (ysub)));
MPFR_ASSERTN (tneg == tsub);
}
mpfr_neg (x, x, MPFR_RNDN);
}
}
mpfr_clear (x);
mpfr_clear (yneg);
mpfr_clear (ysub);
}
static void
check_overflow (void)
{
mpfr_exp_t emin, emax;
mpfr_t x, y1, y2;
int inex1, inex2, rnd_mode;
mpfr_flags_t flags1, flags2;
emin = mpfr_get_emin ();
emax = mpfr_get_emax ();
set_emin (MPFR_EMIN_MIN);
set_emax (MPFR_EMAX_MAX);
mpfr_inits2 (32, x, y1, y2, (mpfr_ptr) 0);
mpfr_setmax (x, MPFR_EMAX_MAX);
mpfr_neg (x, x, MPFR_RNDN);
RND_LOOP_NO_RNDF (rnd_mode)
{
if (rnd_mode == MPFR_RNDU || rnd_mode == MPFR_RNDA)
{
inex1 = mpfr_overflow (y1, (mpfr_rnd_t) rnd_mode, 1);
flags1 = MPFR_FLAGS_OVERFLOW | MPFR_FLAGS_INEXACT;
}
else
{
mpfr_neg (y1, x, MPFR_RNDN);
inex1 = -1;
flags1 = MPFR_FLAGS_INEXACT;
}
mpfr_clear_flags ();
inex2 = mpfr_ui_sub (y2, 1, x, (mpfr_rnd_t) rnd_mode);
flags2 = __gmpfr_flags;
if (!(mpfr_equal_p (y1, y2) &&
SAME_SIGN (inex1, inex2) &&
flags1 == flags2))
{
printf ("Error in check_overflow for %s\n",
mpfr_print_rnd_mode ((mpfr_rnd_t) rnd_mode));
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_clears (x, y1, y2, (mpfr_ptr) 0);
set_emin (emin);
set_emax (emax);
}
#define TEST_FUNCTION mpfr_ui_sub
#define ULONG_ARG1
#include "tgeneric.c"
int
main (int argc, char *argv[])
{
mpfr_prec_t p;
unsigned k;
tests_start_mpfr ();
check_nans ();
special ();
for (p=2; p<100; p++)
for (k=0; k<100; k++)
check_two_sum (p);
check(1196426492, "1.4218093058435347e-3", MPFR_RNDN,
"1.1964264919985781e9");
check(1092583421, "-1.0880649218158844e9", MPFR_RNDN,
"2.1806483428158845901e9");
check(948002822, "1.22191250737771397120e+20", MPFR_RNDN,
"-1.2219125073682338611e20");
check(832100416, "4.68311314939691330000e-215", MPFR_RNDD,
"8.3210041599999988079e8");
check(1976245324, "1.25296395864546893357e+232", MPFR_RNDZ,
"-1.2529639586454686577e232");
check(2128997392, "-1.08496826129284207724e+187", MPFR_RNDU,
"1.0849682612928422704e187");
check(293607738, "-1.9967571564050541e-5", MPFR_RNDU,
"2.9360773800002003e8");
check(354270183, "2.9469161763489528e3", MPFR_RNDN,
"3.5426723608382362e8");
check_overflow ();
check_neg ();
test_generic (MPFR_PREC_MIN, 1000, 100);
tests_end_mpfr ();
return 0;
}