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/*************************************************************************
*
* $Id$
*
* Copyright (C) 2001 Bjorn Reese <breese@users.sourceforge.net>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE AUTHORS AND
* CONTRIBUTORS ACCEPT NO RESPONSIBILITY IN ANY CONCEIVABLE MANNER.
*
************************************************************************
*
* Functions to handle special quantities in floating-point numbers
* (that is, NaNs and infinity). They provide the capability to detect
* and fabricate special quantities.
*
* Although written to be as portable as possible, it can never be
* guaranteed to work on all platforms, as not all hardware supports
* special quantities.
*
* The approach used here (approximately) is to:
*
* 1. Use C99 functionality when available.
* 2. Use IEEE 754 bit-patterns if possible.
* 3. Use platform-specific techniques.
*
************************************************************************/
/*
* TODO:
* o Put all the magic into trio_fpclassify_and_signbit(), and use this from
* trio_isnan() etc.
*/
/*************************************************************************
* Include files
*/
#include "triodef.h"
#include "trionan.h"
#include <math.h>
#include <string.h>
#include <limits.h>
#include <float.h>
#if defined(TRIO_PLATFORM_UNIX)
# include <signal.h>
#endif
#if defined(TRIO_COMPILER_DECC)
# if defined(__linux__)
# include <cpml.h>
# else
# include <fp_class.h>
# endif
#endif
#include <assert.h>
#if defined(TRIO_DOCUMENTATION)
# include "doc/doc_nan.h"
#endif
/** @addtogroup SpecialQuantities
@{
*/
/*************************************************************************
* Definitions
*/
#define TRIO_TRUE (1 == 1)
#define TRIO_FALSE (0 == 1)
/*
* We must enable IEEE floating-point on Alpha
*/
#if defined(__alpha) && !defined(_IEEE_FP)
# if defined(TRIO_COMPILER_DECC)
# if defined(TRIO_PLATFORM_VMS)
# error "Must be compiled with option /IEEE_MODE=UNDERFLOW_TO_ZERO/FLOAT=IEEE"
# else
# if !defined(_CFE)
# error "Must be compiled with option -ieee"
# endif
# endif
# elif defined(TRIO_COMPILER_GCC) && (defined(__osf__) || defined(__linux__))
# error "Must be compiled with option -mieee"
# endif
#endif /* __alpha && ! _IEEE_FP */
/*
* In ANSI/IEEE 754-1985 64-bits double format numbers have the
* following properties (amoungst others)
*
* o FLT_RADIX == 2: binary encoding
* o DBL_MAX_EXP == 1024: 11 bits exponent, where one bit is used
* to indicate special numbers (e.g. NaN and Infinity), so the
* maximum exponent is 10 bits wide (2^10 == 1024).
* o DBL_MANT_DIG == 53: The mantissa is 52 bits wide, but because
* numbers are normalized the initial binary 1 is represented
* implicitly (the so-called "hidden bit"), which leaves us with
* the ability to represent 53 bits wide mantissa.
*/
#if (FLT_RADIX == 2) && (DBL_MAX_EXP == 1024) && (DBL_MANT_DIG == 53)
# define USE_IEEE_754
#endif
/*************************************************************************
* Constants
*/
static TRIO_CONST char rcsid[] = "@(#)$Id$";
#if defined(USE_IEEE_754)
/*
* Endian-agnostic indexing macro.
*
* The value of internalEndianMagic, when converted into a 64-bit
* integer, becomes 0x0706050403020100 (we could have used a 64-bit
* integer value instead of a double, but not all platforms supports
* that type). The value is automatically encoded with the correct
* endianess by the compiler, which means that we can support any
* kind of endianess. The individual bytes are then used as an index
* for the IEEE 754 bit-patterns and masks.
*/
#define TRIO_DOUBLE_INDEX(x) (((unsigned char *)&internalEndianMagic)[7-(x)])
#if (defined(__BORLANDC__) && __BORLANDC__ >= 0x0590)
static TRIO_CONST double internalEndianMagic = 7.949928895127362e-275;
#else
static TRIO_CONST double internalEndianMagic = 7.949928895127363e-275;
#endif
/* Mask for the exponent */
static TRIO_CONST unsigned char ieee_754_exponent_mask[] = {
0x7F, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};
/* Mask for the mantissa */
static TRIO_CONST unsigned char ieee_754_mantissa_mask[] = {
0x00, 0x0F, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
};
/* Mask for the sign bit */
static TRIO_CONST unsigned char ieee_754_sign_mask[] = {
0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};
/* Bit-pattern for negative zero */
static TRIO_CONST unsigned char ieee_754_negzero_array[] = {
0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};
/* Bit-pattern for infinity */
static TRIO_CONST unsigned char ieee_754_infinity_array[] = {
0x7F, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};
/* Bit-pattern for quiet NaN */
static TRIO_CONST unsigned char ieee_754_qnan_array[] = {
0x7F, 0xF8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};
/*************************************************************************
* Functions
*/
/*
* trio_make_double
*/
TRIO_PRIVATE double
trio_make_double
TRIO_ARGS1((values),
TRIO_CONST unsigned char *values)
{
TRIO_VOLATILE double result;
int i;
for (i = 0; i < (int)sizeof(double); i++) {
((TRIO_VOLATILE unsigned char *)&result)[TRIO_DOUBLE_INDEX(i)] = values[i];
}
return result;
}
/*
* trio_is_special_quantity
*/
TRIO_PRIVATE int
trio_is_special_quantity
TRIO_ARGS2((number, has_mantissa),
double number,
int *has_mantissa)
{
unsigned int i;
unsigned char current;
int is_special_quantity = TRIO_TRUE;
*has_mantissa = 0;
for (i = 0; i < (unsigned int)sizeof(double); i++) {
current = ((unsigned char *)&number)[TRIO_DOUBLE_INDEX(i)];
is_special_quantity
&= ((current & ieee_754_exponent_mask[i]) == ieee_754_exponent_mask[i]);
*has_mantissa |= (current & ieee_754_mantissa_mask[i]);
}
return is_special_quantity;
}
/*
* trio_is_negative
*/
TRIO_PRIVATE int
trio_is_negative
TRIO_ARGS1((number),
double number)
{
unsigned int i;
int is_negative = TRIO_FALSE;
for (i = 0; i < (unsigned int)sizeof(double); i++) {
is_negative |= (((unsigned char *)&number)[TRIO_DOUBLE_INDEX(i)]
& ieee_754_sign_mask[i]);
}
return is_negative;
}
#endif /* USE_IEEE_754 */
/**
Generate negative zero.
@return Floating-point representation of negative zero.
*/
TRIO_PUBLIC double
trio_nzero(TRIO_NOARGS)
{
#if defined(USE_IEEE_754)
return trio_make_double(ieee_754_negzero_array);
#else
TRIO_VOLATILE double zero = 0.0;
return -zero;
#endif
}
/**
Generate positive infinity.
@return Floating-point representation of positive infinity.
*/
TRIO_PUBLIC double
trio_pinf(TRIO_NOARGS)
{
/* Cache the result */
static double result = 0.0;
if (result == 0.0) {
#if defined(INFINITY) && defined(__STDC_IEC_559__)
result = (double)INFINITY;
#elif defined(USE_IEEE_754)
result = trio_make_double(ieee_754_infinity_array);
#else
/*
* If HUGE_VAL is different from DBL_MAX, then HUGE_VAL is used
* as infinity. Otherwise we have to resort to an overflow
* operation to generate infinity.
*/
# if defined(TRIO_PLATFORM_UNIX)
void (*signal_handler)(int) = signal(SIGFPE, SIG_IGN);
# endif
result = HUGE_VAL;
if (HUGE_VAL == DBL_MAX) {
/* Force overflow */
result += HUGE_VAL;
}
# if defined(TRIO_PLATFORM_UNIX)
signal(SIGFPE, signal_handler);
# endif
#endif
}
return result;
}
/**
Generate negative infinity.
@return Floating-point value of negative infinity.
*/
TRIO_PUBLIC double
trio_ninf(TRIO_NOARGS)
{
static double result = 0.0;
if (result == 0.0) {
/*
* Negative infinity is calculated by negating positive infinity,
* which can be done because it is legal to do calculations on
* infinity (for example, 1 / infinity == 0).
*/
result = -trio_pinf();
}
return result;
}
/**
Generate NaN.
@return Floating-point representation of NaN.
*/
TRIO_PUBLIC double
trio_nan(TRIO_NOARGS)
{
/* Cache the result */
static double result = 0.0;
if (result == 0.0) {
#if defined(TRIO_COMPILER_SUPPORTS_C99)
result = nan("");
#elif defined(NAN) && defined(__STDC_IEC_559__)
result = (double)NAN;
#elif defined(USE_IEEE_754)
result = trio_make_double(ieee_754_qnan_array);
#else
/*
* There are several ways to generate NaN. The one used here is
* to divide infinity by infinity. I would have preferred to add
* negative infinity to positive infinity, but that yields wrong
* result (infinity) on FreeBSD.
*
* This may fail if the hardware does not support NaN, or if
* the Invalid Operation floating-point exception is unmasked.
*/
# if defined(TRIO_PLATFORM_UNIX)
void (*signal_handler)(int) = signal(SIGFPE, SIG_IGN);
# endif
result = trio_pinf() / trio_pinf();
# if defined(TRIO_PLATFORM_UNIX)
signal(SIGFPE, signal_handler);
# endif
#endif
}
return result;
}
/**
Check for NaN.
@param number An arbitrary floating-point number.
@return Boolean value indicating whether or not the number is a NaN.
*/
TRIO_PUBLIC int
trio_isnan
TRIO_ARGS1((number),
double number)
{
#if (defined(TRIO_COMPILER_SUPPORTS_C99) && defined(isnan)) \
|| defined(TRIO_COMPILER_SUPPORTS_UNIX95)
/*
* C99 defines isnan() as a macro. UNIX95 defines isnan() as a
* function. This function was already present in XPG4, but this
* is a bit tricky to detect with compiler defines, so we choose
* the conservative approach and only use it for UNIX95.
*/
return isnan(number);
#elif defined(TRIO_COMPILER_MSVC) || defined(TRIO_COMPILER_BCB)
/*
* Microsoft Visual C++ and Borland C++ Builder have an _isnan()
* function.
*/
return _isnan(number) ? TRIO_TRUE : TRIO_FALSE;
#elif defined(USE_IEEE_754)
/*
* Examine IEEE 754 bit-pattern. A NaN must have a special exponent
* pattern, and a non-empty mantissa.
*/
int has_mantissa;
int is_special_quantity;
is_special_quantity = trio_is_special_quantity(number, &has_mantissa);
return (is_special_quantity && has_mantissa);
#else
/*
* Fallback solution
*/
int status;
double integral, fraction;
# if defined(TRIO_PLATFORM_UNIX)
void (*signal_handler)(int) = signal(SIGFPE, SIG_IGN);
# endif
status = (/*
* NaN is the only number which does not compare to itself
*/
((TRIO_VOLATILE double)number != (TRIO_VOLATILE double)number) ||
/*
* Fallback solution if NaN compares to NaN
*/
((number != 0.0) &&
(fraction = modf(number, &integral),
integral == fraction)));
# if defined(TRIO_PLATFORM_UNIX)
signal(SIGFPE, signal_handler);
# endif
return status;
#endif
}
/**
Check for infinity.
@param number An arbitrary floating-point number.
@return 1 if positive infinity, -1 if negative infinity, 0 otherwise.
*/
TRIO_PUBLIC int
trio_isinf
TRIO_ARGS1((number),
double number)
{
#if defined(TRIO_COMPILER_DECC) && !defined(__linux__)
/*
* DECC has an isinf() macro, but it works differently than that
* of C99, so we use the fp_class() function instead.
*/
return ((fp_class(number) == FP_POS_INF)
? 1
: ((fp_class(number) == FP_NEG_INF) ? -1 : 0));
#elif defined(isinf)
/*
* C99 defines isinf() as a macro.
*/
return isinf(number)
? ((number > 0.0) ? 1 : -1)
: 0;
#elif defined(TRIO_COMPILER_MSVC) || defined(TRIO_COMPILER_BCB)
/*
* Microsoft Visual C++ and Borland C++ Builder have an _fpclass()
* function that can be used to detect infinity.
*/
return ((_fpclass(number) == _FPCLASS_PINF)
? 1
: ((_fpclass(number) == _FPCLASS_NINF) ? -1 : 0));
#elif defined(USE_IEEE_754)
/*
* Examine IEEE 754 bit-pattern. Infinity must have a special exponent
* pattern, and an empty mantissa.
*/
int has_mantissa;
int is_special_quantity;
is_special_quantity = trio_is_special_quantity(number, &has_mantissa);
return (is_special_quantity && !has_mantissa)
? ((number < 0.0) ? -1 : 1)
: 0;
#else
/*
* Fallback solution.
*/
int status;
# if defined(TRIO_PLATFORM_UNIX)
void (*signal_handler)(int) = signal(SIGFPE, SIG_IGN);
# endif
double infinity = trio_pinf();
status = ((number == infinity)
? 1
: ((number == -infinity) ? -1 : 0));
# if defined(TRIO_PLATFORM_UNIX)
signal(SIGFPE, signal_handler);
# endif
return status;
#endif
}
#if 0
/* Temporary fix - this routine is not used anywhere */
/**
Check for finity.
@param number An arbitrary floating-point number.
@return Boolean value indicating whether or not the number is a finite.
*/
TRIO_PUBLIC int
trio_isfinite
TRIO_ARGS1((number),
double number)
{
#if defined(TRIO_COMPILER_SUPPORTS_C99) && defined(isfinite)
/*
* C99 defines isfinite() as a macro.
*/
return isfinite(number);
#elif defined(TRIO_COMPILER_MSVC) || defined(TRIO_COMPILER_BCB)
/*
* Microsoft Visual C++ and Borland C++ Builder use _finite().
*/
return _finite(number);
#elif defined(USE_IEEE_754)
/*
* Examine IEEE 754 bit-pattern. For finity we do not care about the
* mantissa.
*/
int dummy;
return (! trio_is_special_quantity(number, &dummy));
#else
/*
* Fallback solution.
*/
return ((trio_isinf(number) == 0) && (trio_isnan(number) == 0));
#endif
}
#endif
/*
* The sign of NaN is always false
*/
TRIO_PUBLIC int
trio_fpclassify_and_signbit
TRIO_ARGS2((number, is_negative),
double number,
int *is_negative)
{
#if defined(fpclassify) && defined(signbit)
/*
* C99 defines fpclassify() and signbit() as a macros
*/
*is_negative = signbit(number);
switch (fpclassify(number)) {
case FP_NAN:
return TRIO_FP_NAN;
case FP_INFINITE:
return TRIO_FP_INFINITE;
case FP_SUBNORMAL:
return TRIO_FP_SUBNORMAL;
case FP_ZERO:
return TRIO_FP_ZERO;
default:
return TRIO_FP_NORMAL;
}
#else
# if defined(TRIO_COMPILER_DECC)
/*
* DECC has an fp_class() function.
*/
# define TRIO_FPCLASSIFY(n) fp_class(n)
# define TRIO_QUIET_NAN FP_QNAN
# define TRIO_SIGNALLING_NAN FP_SNAN
# define TRIO_POSITIVE_INFINITY FP_POS_INF
# define TRIO_NEGATIVE_INFINITY FP_NEG_INF
# define TRIO_POSITIVE_SUBNORMAL FP_POS_DENORM
# define TRIO_NEGATIVE_SUBNORMAL FP_NEG_DENORM
# define TRIO_POSITIVE_ZERO FP_POS_ZERO
# define TRIO_NEGATIVE_ZERO FP_NEG_ZERO
# define TRIO_POSITIVE_NORMAL FP_POS_NORM
# define TRIO_NEGATIVE_NORMAL FP_NEG_NORM
# elif defined(TRIO_COMPILER_MSVC) || defined(TRIO_COMPILER_BCB)
/*
* Microsoft Visual C++ and Borland C++ Builder have an _fpclass()
* function.
*/
# define TRIO_FPCLASSIFY(n) _fpclass(n)
# define TRIO_QUIET_NAN _FPCLASS_QNAN
# define TRIO_SIGNALLING_NAN _FPCLASS_SNAN
# define TRIO_POSITIVE_INFINITY _FPCLASS_PINF
# define TRIO_NEGATIVE_INFINITY _FPCLASS_NINF
# define TRIO_POSITIVE_SUBNORMAL _FPCLASS_PD
# define TRIO_NEGATIVE_SUBNORMAL _FPCLASS_ND
# define TRIO_POSITIVE_ZERO _FPCLASS_PZ
# define TRIO_NEGATIVE_ZERO _FPCLASS_NZ
# define TRIO_POSITIVE_NORMAL _FPCLASS_PN
# define TRIO_NEGATIVE_NORMAL _FPCLASS_NN
# elif defined(FP_PLUS_NORM)
/*
* HP-UX 9.x and 10.x have an fpclassify() function, that is different
* from the C99 fpclassify() macro supported on HP-UX 11.x.
*
* AIX has class() for C, and _class() for C++, which returns the
* same values as the HP-UX fpclassify() function.
*/
# if defined(TRIO_PLATFORM_AIX)
# if defined(__cplusplus)
# define TRIO_FPCLASSIFY(n) _class(n)
# else
# define TRIO_FPCLASSIFY(n) class(n)
# endif
# else
# define TRIO_FPCLASSIFY(n) fpclassify(n)
# endif
# define TRIO_QUIET_NAN FP_QNAN
# define TRIO_SIGNALLING_NAN FP_SNAN
# define TRIO_POSITIVE_INFINITY FP_PLUS_INF
# define TRIO_NEGATIVE_INFINITY FP_MINUS_INF
# define TRIO_POSITIVE_SUBNORMAL FP_PLUS_DENORM
# define TRIO_NEGATIVE_SUBNORMAL FP_MINUS_DENORM
# define TRIO_POSITIVE_ZERO FP_PLUS_ZERO
# define TRIO_NEGATIVE_ZERO FP_MINUS_ZERO
# define TRIO_POSITIVE_NORMAL FP_PLUS_NORM
# define TRIO_NEGATIVE_NORMAL FP_MINUS_NORM
# endif
# if defined(TRIO_FPCLASSIFY)
switch (TRIO_FPCLASSIFY(number)) {
case TRIO_QUIET_NAN:
case TRIO_SIGNALLING_NAN:
*is_negative = TRIO_FALSE; /* NaN has no sign */
return TRIO_FP_NAN;
case TRIO_POSITIVE_INFINITY:
*is_negative = TRIO_FALSE;
return TRIO_FP_INFINITE;
case TRIO_NEGATIVE_INFINITY:
*is_negative = TRIO_TRUE;
return TRIO_FP_INFINITE;
case TRIO_POSITIVE_SUBNORMAL:
*is_negative = TRIO_FALSE;
return TRIO_FP_SUBNORMAL;
case TRIO_NEGATIVE_SUBNORMAL:
*is_negative = TRIO_TRUE;
return TRIO_FP_SUBNORMAL;
case TRIO_POSITIVE_ZERO:
*is_negative = TRIO_FALSE;
return TRIO_FP_ZERO;
case TRIO_NEGATIVE_ZERO:
*is_negative = TRIO_TRUE;
return TRIO_FP_ZERO;
case TRIO_POSITIVE_NORMAL:
*is_negative = TRIO_FALSE;
return TRIO_FP_NORMAL;
case TRIO_NEGATIVE_NORMAL:
*is_negative = TRIO_TRUE;
return TRIO_FP_NORMAL;
default:
/* Just in case... */
*is_negative = (number < 0.0);
return TRIO_FP_NORMAL;
}
# else
/*
* Fallback solution.
*/
int rc;
if (number == 0.0) {
/*
* In IEEE 754 the sign of zero is ignored in comparisons, so we
* have to handle this as a special case by examining the sign bit
* directly.
*/
# if defined(USE_IEEE_754)
*is_negative = trio_is_negative(number);
# else
*is_negative = TRIO_FALSE; /* FIXME */
# endif
return TRIO_FP_ZERO;
}
if (trio_isnan(number)) {
*is_negative = TRIO_FALSE;
return TRIO_FP_NAN;
}
if ((rc = trio_isinf(number))) {
*is_negative = (rc == -1);
return TRIO_FP_INFINITE;
}
if ((number > 0.0) && (number < DBL_MIN)) {
*is_negative = TRIO_FALSE;
return TRIO_FP_SUBNORMAL;
}
if ((number < 0.0) && (number > -DBL_MIN)) {
*is_negative = TRIO_TRUE;
return TRIO_FP_SUBNORMAL;
}
*is_negative = (number < 0.0);
return TRIO_FP_NORMAL;
# endif
#endif
}
/**
Examine the sign of a number.
@param number An arbitrary floating-point number.
@return Boolean value indicating whether or not the number has the
sign bit set (i.e. is negative).
*/
TRIO_PUBLIC int
trio_signbit
TRIO_ARGS1((number),
double number)
{
int is_negative;
(void)trio_fpclassify_and_signbit(number, &is_negative);
return is_negative;
}
#if 0
/* Temporary fix - this routine is not used in libxml */
/**
Examine the class of a number.
@param number An arbitrary floating-point number.
@return Enumerable value indicating the class of @p number
*/
TRIO_PUBLIC int
trio_fpclassify
TRIO_ARGS1((number),
double number)
{
int dummy;
return trio_fpclassify_and_signbit(number, &dummy);
}
#endif
/** @} SpecialQuantities */
/*************************************************************************
* For test purposes.
*
* Add the following compiler option to include this test code.
*
* Unix : -DSTANDALONE
* VMS : /DEFINE=(STANDALONE)
*/
#if defined(STANDALONE)
# include <stdio.h>
static TRIO_CONST char *
getClassification
TRIO_ARGS1((type),
int type)
{
switch (type) {
case TRIO_FP_INFINITE:
return "FP_INFINITE";
case TRIO_FP_NAN:
return "FP_NAN";
case TRIO_FP_NORMAL:
return "FP_NORMAL";
case TRIO_FP_SUBNORMAL:
return "FP_SUBNORMAL";
case TRIO_FP_ZERO:
return "FP_ZERO";
default:
return "FP_UNKNOWN";
}
}
static void
print_class
TRIO_ARGS2((prefix, number),
TRIO_CONST char *prefix,
double number)
{
printf("%-6s: %s %-15s %g\n",
prefix,
trio_signbit(number) ? "-" : "+",
getClassification(TRIO_FPCLASSIFY(number)),
number);
}
int main(TRIO_NOARGS)
{
double my_nan;
double my_pinf;
double my_ninf;
# if defined(TRIO_PLATFORM_UNIX)
void (*signal_handler) TRIO_PROTO((int));
# endif
my_nan = trio_nan();
my_pinf = trio_pinf();
my_ninf = trio_ninf();
print_class("Nan", my_nan);
print_class("PInf", my_pinf);
print_class("NInf", my_ninf);
print_class("PZero", 0.0);
print_class("NZero", -0.0);
print_class("PNorm", 1.0);
print_class("NNorm", -1.0);
print_class("PSub", 1.01e-307 - 1.00e-307);
print_class("NSub", 1.00e-307 - 1.01e-307);
printf("NaN : %4g 0x%02x%02x%02x%02x%02x%02x%02x%02x (%2d, %2d)\n",
my_nan,
((unsigned char *)&my_nan)[0],
((unsigned char *)&my_nan)[1],
((unsigned char *)&my_nan)[2],
((unsigned char *)&my_nan)[3],
((unsigned char *)&my_nan)[4],
((unsigned char *)&my_nan)[5],
((unsigned char *)&my_nan)[6],
((unsigned char *)&my_nan)[7],
trio_isnan(my_nan), trio_isinf(my_nan));
printf("PInf: %4g 0x%02x%02x%02x%02x%02x%02x%02x%02x (%2d, %2d)\n",
my_pinf,
((unsigned char *)&my_pinf)[0],
((unsigned char *)&my_pinf)[1],
((unsigned char *)&my_pinf)[2],
((unsigned char *)&my_pinf)[3],
((unsigned char *)&my_pinf)[4],
((unsigned char *)&my_pinf)[5],
((unsigned char *)&my_pinf)[6],
((unsigned char *)&my_pinf)[7],
trio_isnan(my_pinf), trio_isinf(my_pinf));
printf("NInf: %4g 0x%02x%02x%02x%02x%02x%02x%02x%02x (%2d, %2d)\n",
my_ninf,
((unsigned char *)&my_ninf)[0],
((unsigned char *)&my_ninf)[1],
((unsigned char *)&my_ninf)[2],
((unsigned char *)&my_ninf)[3],
((unsigned char *)&my_ninf)[4],
((unsigned char *)&my_ninf)[5],
((unsigned char *)&my_ninf)[6],
((unsigned char *)&my_ninf)[7],
trio_isnan(my_ninf), trio_isinf(my_ninf));
# if defined(TRIO_PLATFORM_UNIX)
signal_handler = signal(SIGFPE, SIG_IGN);
# endif
my_pinf = DBL_MAX + DBL_MAX;
my_ninf = -my_pinf;
my_nan = my_pinf / my_pinf;
# if defined(TRIO_PLATFORM_UNIX)
signal(SIGFPE, signal_handler);
# endif
printf("NaN : %4g 0x%02x%02x%02x%02x%02x%02x%02x%02x (%2d, %2d)\n",
my_nan,
((unsigned char *)&my_nan)[0],
((unsigned char *)&my_nan)[1],
((unsigned char *)&my_nan)[2],
((unsigned char *)&my_nan)[3],
((unsigned char *)&my_nan)[4],
((unsigned char *)&my_nan)[5],
((unsigned char *)&my_nan)[6],
((unsigned char *)&my_nan)[7],
trio_isnan(my_nan), trio_isinf(my_nan));
printf("PInf: %4g 0x%02x%02x%02x%02x%02x%02x%02x%02x (%2d, %2d)\n",
my_pinf,
((unsigned char *)&my_pinf)[0],
((unsigned char *)&my_pinf)[1],
((unsigned char *)&my_pinf)[2],
((unsigned char *)&my_pinf)[3],
((unsigned char *)&my_pinf)[4],
((unsigned char *)&my_pinf)[5],
((unsigned char *)&my_pinf)[6],
((unsigned char *)&my_pinf)[7],
trio_isnan(my_pinf), trio_isinf(my_pinf));
printf("NInf: %4g 0x%02x%02x%02x%02x%02x%02x%02x%02x (%2d, %2d)\n",
my_ninf,
((unsigned char *)&my_ninf)[0],
((unsigned char *)&my_ninf)[1],
((unsigned char *)&my_ninf)[2],
((unsigned char *)&my_ninf)[3],
((unsigned char *)&my_ninf)[4],
((unsigned char *)&my_ninf)[5],
((unsigned char *)&my_ninf)[6],
((unsigned char *)&my_ninf)[7],
trio_isnan(my_ninf), trio_isinf(my_ninf));
return 0;
}
#endif
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