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/* Test of signbit() substitute.
Copyright (C) 2007, 2008, 2009, 2010 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>
/* signbit must be a macro. */
#ifndef signbit
# error missing declaration
#endif
#include <float.h>
#include <limits.h>
#include "macros.h"
float zerof = 0.0f;
double zerod = 0.0;
long double zerol = 0.0L;
/* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0f.
So we use -zerof instead. */
/* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0.
So we use -zerod instead. */
/* On HP-UX 10.20, negating 0.0L does not yield -0.0L.
So we use minus_zerol instead.
IRIX cc can't put -0.0L into .data, but can compute at runtime.
Note that the expression -LDBL_MIN * LDBL_MIN does not work on other
platforms, such as when cross-compiling to PowerPC on MacOS X 10.5. */
#if defined __hpux || defined __sgi
static long double
compute_minus_zerol (void)
{
return -LDBL_MIN * LDBL_MIN;
}
# define minus_zerol compute_minus_zerol ()
#else
long double minus_zerol = -0.0L;
#endif
static void
test_signbitf ()
{
/* Finite values. */
ASSERT (!signbit (3.141f));
ASSERT (!signbit (3.141e30f));
ASSERT (!signbit (3.141e-30f));
ASSERT (signbit (-2.718f));
ASSERT (signbit (-2.718e30f));
ASSERT (signbit (-2.718e-30f));
/* Zeros. */
ASSERT (!signbit (0.0f));
if (1.0f / -zerof < 0)
ASSERT (signbit (-zerof));
else
ASSERT (!signbit (-zerof));
/* Infinite values. */
ASSERT (!signbit (1.0f / 0.0f));
ASSERT (signbit (-1.0f / 0.0f));
/* Quiet NaN. */
(void) signbit (zerof / zerof);
#if defined FLT_EXPBIT0_WORD && defined FLT_EXPBIT0_BIT
/* Signalling NaN. */
{
#define NWORDS \
((sizeof (float) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
typedef union { float value; unsigned int word[NWORDS]; } memory_float;
memory_float m;
m.value = zerof / zerof;
# if FLT_EXPBIT0_BIT > 0
m.word[FLT_EXPBIT0_WORD] ^= (unsigned int) 1 << (FLT_EXPBIT0_BIT - 1);
# else
m.word[FLT_EXPBIT0_WORD + (FLT_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
# endif
if (FLT_EXPBIT0_WORD < NWORDS / 2)
m.word[FLT_EXPBIT0_WORD + 1] |= (unsigned int) 1 << FLT_EXPBIT0_BIT;
else
m.word[0] |= (unsigned int) 1;
(void) signbit (m.value);
#undef NWORDS
}
#endif
}
static void
test_signbitd ()
{
/* Finite values. */
ASSERT (!signbit (3.141));
ASSERT (!signbit (3.141e30));
ASSERT (!signbit (3.141e-30));
ASSERT (signbit (-2.718));
ASSERT (signbit (-2.718e30));
ASSERT (signbit (-2.718e-30));
/* Zeros. */
ASSERT (!signbit (0.0));
if (1.0 / -zerod < 0)
ASSERT (signbit (-zerod));
else
ASSERT (!signbit (-zerod));
/* Infinite values. */
ASSERT (!signbit (1.0 / 0.0));
ASSERT (signbit (-1.0 / 0.0));
/* Quiet NaN. */
(void) signbit (zerod / zerod);
#if defined DBL_EXPBIT0_WORD && defined DBL_EXPBIT0_BIT
/* Signalling NaN. */
{
#define NWORDS \
((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
typedef union { double value; unsigned int word[NWORDS]; } memory_double;
memory_double m;
m.value = zerod / zerod;
# if DBL_EXPBIT0_BIT > 0
m.word[DBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (DBL_EXPBIT0_BIT - 1);
# else
m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
# endif
m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
|= (unsigned int) 1 << DBL_EXPBIT0_BIT;
(void) signbit (m.value);
#undef NWORDS
}
#endif
}
static void
test_signbitl ()
{
/* Finite values. */
ASSERT (!signbit (3.141L));
ASSERT (!signbit (3.141e30L));
ASSERT (!signbit (3.141e-30L));
ASSERT (signbit (-2.718L));
ASSERT (signbit (-2.718e30L));
ASSERT (signbit (-2.718e-30L));
/* Zeros. */
ASSERT (!signbit (0.0L));
if (1.0L / minus_zerol < 0)
ASSERT (signbit (minus_zerol));
else
ASSERT (!signbit (minus_zerol));
/* Infinite values. */
ASSERT (!signbit (1.0L / 0.0L));
ASSERT (signbit (-1.0L / 0.0L));
/* Quiet NaN. */
(void) signbit (zerol / zerol);
#if defined LDBL_EXPBIT0_WORD && defined LDBL_EXPBIT0_BIT
/* Signalling NaN. */
{
#define NWORDS \
((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
typedef union { long double value; unsigned int word[NWORDS]; } memory_long_double;
#if defined __powerpc__ && LDBL_MANT_DIG == 106
/* This is PowerPC "double double", a pair of two doubles. Inf and Nan are
represented as the corresponding 64-bit IEEE values in the first double;
the second is ignored. Manipulate only the first double. */
#undef NWORDS
#define NWORDS \
((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
#endif
memory_long_double m;
m.value = zerol / zerol;
# if LDBL_EXPBIT0_BIT > 0
m.word[LDBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (LDBL_EXPBIT0_BIT - 1);
# else
m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
# endif
m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
|= (unsigned int) 1 << LDBL_EXPBIT0_BIT;
(void) signbit (m.value);
#undef NWORDS
}
#endif
}
int
main ()
{
test_signbitf ();
test_signbitd ();
test_signbitl ();
return 0;
}
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