1
0
mirror of https://git.savannah.gnu.org/git/gnulib.git synced 2025-08-17 12:41:05 +03:00
Files
gnulib/tests/test-ldexpl.c
2008-04-11 16:31:39 +02:00

124 lines
3.4 KiB
C

/* Test of multiplying a 'long double' by a power of 2.
Copyright (C) 2007-2008 Free Software Foundation, Inc.
This program 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 of the License, or
(at your option) any later version.
This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */
/* Written by Bruno Haible <bruno@clisp.org>, 2007. */
#include <config.h>
#include <math.h>
#include <float.h>
#include <stdio.h>
#include <stdlib.h>
#include "fpucw.h"
#include "isnanl-nolibm.h"
#define ASSERT(expr) \
do \
{ \
if (!(expr)) \
{ \
fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \
fflush (stderr); \
abort (); \
} \
} \
while (0)
int
main ()
{
int i;
long double x;
long double y;
DECL_LONG_DOUBLE_ROUNDING
BEGIN_LONG_DOUBLE_ROUNDING ();
{ /* NaN. */
x = 0.0L / 0.0L;
y = ldexpl (x, 0); ASSERT (isnanl (y));
y = ldexpl (x, 5); ASSERT (isnanl (y));
y = ldexpl (x, -5); ASSERT (isnanl (y));
}
{ /* Positive infinity. */
x = 1.0L / 0.0L;
y = ldexpl (x, 0); ASSERT (y == x);
y = ldexpl (x, 5); ASSERT (y == x);
y = ldexpl (x, -5); ASSERT (y == x);
}
{ /* Negative infinity. */
x = -1.0L / 0.0L;
y = ldexpl (x, 0); ASSERT (y == x);
y = ldexpl (x, 5); ASSERT (y == x);
y = ldexpl (x, -5); ASSERT (y == x);
}
{ /* Positive zero. */
x = 0.0L;
y = ldexpl (x, 0); ASSERT (y == x); ASSERT (!signbit (x));
y = ldexpl (x, 5); ASSERT (y == x); ASSERT (!signbit (x));
y = ldexpl (x, -5); ASSERT (y == x); ASSERT (!signbit (x));
}
{ /* Negative zero. */
x = -0.0L;
y = ldexpl (x, 0); ASSERT (y == x); ASSERT (signbit (x));
y = ldexpl (x, 5); ASSERT (y == x); ASSERT (signbit (x));
y = ldexpl (x, -5); ASSERT (y == x); ASSERT (signbit (x));
}
{ /* Positive finite number. */
x = 1.73205L;
y = ldexpl (x, 0); ASSERT (y == x);
y = ldexpl (x, 5); ASSERT (y == x * 32.0L);
y = ldexpl (x, -5); ASSERT (y == x * 0.03125L);
}
{ /* Negative finite number. */
x = -20.085536923187667742L;
y = ldexpl (x, 0); ASSERT (y == x);
y = ldexpl (x, 5); ASSERT (y == x * 32.0L);
y = ldexpl (x, -5); ASSERT (y == x * 0.03125L);
}
for (i = 1, x = 1.73205L; i <= LDBL_MAX_EXP; i++, x *= 2.0L)
{
y = ldexpl (x, 0); ASSERT (y == x);
y = ldexpl (x, 5); ASSERT (y == x * 32.0L);
y = ldexpl (x, -5); ASSERT (y == x * 0.03125L);
}
for (i = 1, x = 1.73205L; i >= LDBL_MIN_EXP; i--, x *= 0.5L)
{
y = ldexpl (x, 0); ASSERT (y == x);
y = ldexpl (x, 5); ASSERT (y == x * 32.0L);
if (i - 5 >= LDBL_MIN_EXP)
{
y = ldexpl (x, -5); ASSERT (y == x * 0.03125L);
}
}
for (; i >= LDBL_MIN_EXP - 100 && x > 0.0L; i--, x *= 0.5L)
{
y = ldexpl (x, 0); ASSERT (y == x);
y = ldexpl (x, 5); ASSERT (y == x * 32.0L);
}
return 0;
}