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914 lines
23 KiB
C
914 lines
23 KiB
C
/*************************************************************************
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*
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* $Id$
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*
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* Copyright (C) 2001 Bjorn Reese <breese@users.sourceforge.net>
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*
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* Permission to use, copy, modify, and distribute this software for any
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* purpose with or without fee is hereby granted, provided that the above
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* copyright notice and this permission notice appear in all copies.
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*
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
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* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
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* MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE AUTHORS AND
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* CONTRIBUTORS ACCEPT NO RESPONSIBILITY IN ANY CONCEIVABLE MANNER.
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*
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************************************************************************
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*
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* Functions to handle special quantities in floating-point numbers
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* (that is, NaNs and infinity). They provide the capability to detect
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* and fabricate special quantities.
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*
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* Although written to be as portable as possible, it can never be
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* guaranteed to work on all platforms, as not all hardware supports
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* special quantities.
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*
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* The approach used here (approximately) is to:
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*
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* 1. Use C99 functionality when available.
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* 2. Use IEEE 754 bit-patterns if possible.
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* 3. Use platform-specific techniques.
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*
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************************************************************************/
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/*
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* TODO:
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* o Put all the magic into trio_fpclassify_and_signbit(), and use this from
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* trio_isnan() etc.
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*/
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/*************************************************************************
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* Include files
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*/
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#include "triodef.h"
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#include "trionan.h"
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#include <math.h>
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#include <string.h>
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#include <limits.h>
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#include <float.h>
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#if defined(TRIO_PLATFORM_UNIX)
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# include <signal.h>
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#endif
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#if defined(TRIO_COMPILER_DECC)
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# if defined(__linux__)
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# include <cpml.h>
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# else
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# include <fp_class.h>
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# endif
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#endif
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#include <assert.h>
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#if defined(TRIO_DOCUMENTATION)
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# include "doc/doc_nan.h"
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#endif
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/** @addtogroup SpecialQuantities
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@{
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*/
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/*************************************************************************
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* Definitions
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*/
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#define TRIO_TRUE (1 == 1)
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#define TRIO_FALSE (0 == 1)
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/*
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* We must enable IEEE floating-point on Alpha
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*/
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#if defined(__alpha) && !defined(_IEEE_FP)
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# if defined(TRIO_COMPILER_DECC)
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# if defined(TRIO_PLATFORM_VMS)
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# error "Must be compiled with option /IEEE_MODE=UNDERFLOW_TO_ZERO/FLOAT=IEEE"
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# else
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# if !defined(_CFE)
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# error "Must be compiled with option -ieee"
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# endif
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# endif
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# elif defined(TRIO_COMPILER_GCC) && (defined(__osf__) || defined(__linux__))
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# error "Must be compiled with option -mieee"
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# endif
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#endif /* __alpha && ! _IEEE_FP */
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/*
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* In ANSI/IEEE 754-1985 64-bits double format numbers have the
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* following properties (amoungst others)
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*
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* o FLT_RADIX == 2: binary encoding
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* o DBL_MAX_EXP == 1024: 11 bits exponent, where one bit is used
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* to indicate special numbers (e.g. NaN and Infinity), so the
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* maximum exponent is 10 bits wide (2^10 == 1024).
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* o DBL_MANT_DIG == 53: The mantissa is 52 bits wide, but because
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* numbers are normalized the initial binary 1 is represented
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* implicitly (the so-called "hidden bit"), which leaves us with
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* the ability to represent 53 bits wide mantissa.
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*/
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#if (FLT_RADIX == 2) && (DBL_MAX_EXP == 1024) && (DBL_MANT_DIG == 53)
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# define USE_IEEE_754
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#endif
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/*************************************************************************
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* Constants
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*/
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static TRIO_CONST char rcsid[] = "@(#)$Id$";
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#if defined(USE_IEEE_754)
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/*
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* Endian-agnostic indexing macro.
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*
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* The value of internalEndianMagic, when converted into a 64-bit
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* integer, becomes 0x0706050403020100 (we could have used a 64-bit
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* integer value instead of a double, but not all platforms supports
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* that type). The value is automatically encoded with the correct
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* endianess by the compiler, which means that we can support any
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* kind of endianess. The individual bytes are then used as an index
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* for the IEEE 754 bit-patterns and masks.
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*/
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#define TRIO_DOUBLE_INDEX(x) (((unsigned char *)&internalEndianMagic)[7-(x)])
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#if (defined(__BORLANDC__) && __BORLANDC__ >= 0x0590)
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static TRIO_CONST double internalEndianMagic = 7.949928895127362e-275;
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#else
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static TRIO_CONST double internalEndianMagic = 7.949928895127363e-275;
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#endif
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/* Mask for the exponent */
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static TRIO_CONST unsigned char ieee_754_exponent_mask[] = {
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0x7F, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
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};
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/* Mask for the mantissa */
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static TRIO_CONST unsigned char ieee_754_mantissa_mask[] = {
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0x00, 0x0F, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
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};
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/* Mask for the sign bit */
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static TRIO_CONST unsigned char ieee_754_sign_mask[] = {
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0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
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};
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/* Bit-pattern for negative zero */
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static TRIO_CONST unsigned char ieee_754_negzero_array[] = {
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0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
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};
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/* Bit-pattern for infinity */
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static TRIO_CONST unsigned char ieee_754_infinity_array[] = {
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0x7F, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
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};
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/* Bit-pattern for quiet NaN */
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static TRIO_CONST unsigned char ieee_754_qnan_array[] = {
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0x7F, 0xF8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
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};
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/*************************************************************************
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* Functions
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*/
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/*
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* trio_make_double
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*/
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TRIO_PRIVATE double
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trio_make_double
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TRIO_ARGS1((values),
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TRIO_CONST unsigned char *values)
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{
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TRIO_VOLATILE double result;
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int i;
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for (i = 0; i < (int)sizeof(double); i++) {
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((TRIO_VOLATILE unsigned char *)&result)[TRIO_DOUBLE_INDEX(i)] = values[i];
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}
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return result;
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}
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/*
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* trio_is_special_quantity
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*/
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TRIO_PRIVATE int
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trio_is_special_quantity
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TRIO_ARGS2((number, has_mantissa),
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double number,
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int *has_mantissa)
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{
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unsigned int i;
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unsigned char current;
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int is_special_quantity = TRIO_TRUE;
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*has_mantissa = 0;
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for (i = 0; i < (unsigned int)sizeof(double); i++) {
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current = ((unsigned char *)&number)[TRIO_DOUBLE_INDEX(i)];
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is_special_quantity
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&= ((current & ieee_754_exponent_mask[i]) == ieee_754_exponent_mask[i]);
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*has_mantissa |= (current & ieee_754_mantissa_mask[i]);
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}
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return is_special_quantity;
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}
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/*
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* trio_is_negative
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*/
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TRIO_PRIVATE int
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trio_is_negative
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TRIO_ARGS1((number),
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double number)
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{
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unsigned int i;
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int is_negative = TRIO_FALSE;
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for (i = 0; i < (unsigned int)sizeof(double); i++) {
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is_negative |= (((unsigned char *)&number)[TRIO_DOUBLE_INDEX(i)]
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& ieee_754_sign_mask[i]);
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}
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return is_negative;
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}
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#endif /* USE_IEEE_754 */
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/**
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Generate negative zero.
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@return Floating-point representation of negative zero.
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*/
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TRIO_PUBLIC double
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trio_nzero(TRIO_NOARGS)
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{
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#if defined(USE_IEEE_754)
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return trio_make_double(ieee_754_negzero_array);
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#else
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TRIO_VOLATILE double zero = 0.0;
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return -zero;
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#endif
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}
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/**
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Generate positive infinity.
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@return Floating-point representation of positive infinity.
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*/
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TRIO_PUBLIC double
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trio_pinf(TRIO_NOARGS)
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{
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/* Cache the result */
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static double result = 0.0;
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if (result == 0.0) {
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#if defined(INFINITY) && defined(__STDC_IEC_559__)
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result = (double)INFINITY;
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#elif defined(USE_IEEE_754)
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result = trio_make_double(ieee_754_infinity_array);
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#else
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/*
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* If HUGE_VAL is different from DBL_MAX, then HUGE_VAL is used
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* as infinity. Otherwise we have to resort to an overflow
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* operation to generate infinity.
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*/
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# if defined(TRIO_PLATFORM_UNIX)
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void (*signal_handler)(int) = signal(SIGFPE, SIG_IGN);
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# endif
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result = HUGE_VAL;
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if (HUGE_VAL == DBL_MAX) {
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/* Force overflow */
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result += HUGE_VAL;
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}
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# if defined(TRIO_PLATFORM_UNIX)
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signal(SIGFPE, signal_handler);
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# endif
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#endif
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}
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return result;
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}
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/**
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Generate negative infinity.
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@return Floating-point value of negative infinity.
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*/
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TRIO_PUBLIC double
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trio_ninf(TRIO_NOARGS)
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{
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static double result = 0.0;
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if (result == 0.0) {
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/*
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* Negative infinity is calculated by negating positive infinity,
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* which can be done because it is legal to do calculations on
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* infinity (for example, 1 / infinity == 0).
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*/
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result = -trio_pinf();
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}
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return result;
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}
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/**
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Generate NaN.
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@return Floating-point representation of NaN.
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*/
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TRIO_PUBLIC double
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trio_nan(TRIO_NOARGS)
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{
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/* Cache the result */
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static double result = 0.0;
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if (result == 0.0) {
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#if defined(TRIO_COMPILER_SUPPORTS_C99)
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result = nan("");
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#elif defined(NAN) && defined(__STDC_IEC_559__)
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result = (double)NAN;
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#elif defined(USE_IEEE_754)
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result = trio_make_double(ieee_754_qnan_array);
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#else
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/*
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* There are several ways to generate NaN. The one used here is
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* to divide infinity by infinity. I would have preferred to add
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* negative infinity to positive infinity, but that yields wrong
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* result (infinity) on FreeBSD.
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*
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* This may fail if the hardware does not support NaN, or if
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* the Invalid Operation floating-point exception is unmasked.
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*/
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# if defined(TRIO_PLATFORM_UNIX)
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void (*signal_handler)(int) = signal(SIGFPE, SIG_IGN);
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# endif
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result = trio_pinf() / trio_pinf();
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# if defined(TRIO_PLATFORM_UNIX)
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signal(SIGFPE, signal_handler);
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# endif
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#endif
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}
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return result;
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}
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/**
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Check for NaN.
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@param number An arbitrary floating-point number.
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@return Boolean value indicating whether or not the number is a NaN.
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*/
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TRIO_PUBLIC int
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trio_isnan
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TRIO_ARGS1((number),
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double number)
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{
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#if (defined(TRIO_COMPILER_SUPPORTS_C99) && defined(isnan)) \
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|| defined(TRIO_COMPILER_SUPPORTS_UNIX95)
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/*
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* C99 defines isnan() as a macro. UNIX95 defines isnan() as a
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* function. This function was already present in XPG4, but this
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* is a bit tricky to detect with compiler defines, so we choose
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* the conservative approach and only use it for UNIX95.
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*/
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return isnan(number);
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#elif defined(TRIO_COMPILER_MSVC) || defined(TRIO_COMPILER_BCB)
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/*
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* Microsoft Visual C++ and Borland C++ Builder have an _isnan()
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* function.
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*/
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return _isnan(number) ? TRIO_TRUE : TRIO_FALSE;
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#elif defined(USE_IEEE_754)
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/*
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* Examine IEEE 754 bit-pattern. A NaN must have a special exponent
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* pattern, and a non-empty mantissa.
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*/
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int has_mantissa;
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int is_special_quantity;
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is_special_quantity = trio_is_special_quantity(number, &has_mantissa);
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return (is_special_quantity && has_mantissa);
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#else
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/*
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* Fallback solution
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*/
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int status;
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double integral, fraction;
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# if defined(TRIO_PLATFORM_UNIX)
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void (*signal_handler)(int) = signal(SIGFPE, SIG_IGN);
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# endif
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status = (/*
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* NaN is the only number which does not compare to itself
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*/
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((TRIO_VOLATILE double)number != (TRIO_VOLATILE double)number) ||
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/*
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* Fallback solution if NaN compares to NaN
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*/
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((number != 0.0) &&
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(fraction = modf(number, &integral),
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integral == fraction)));
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# if defined(TRIO_PLATFORM_UNIX)
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signal(SIGFPE, signal_handler);
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# endif
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return status;
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#endif
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}
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|
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/**
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Check for infinity.
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@param number An arbitrary floating-point number.
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@return 1 if positive infinity, -1 if negative infinity, 0 otherwise.
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*/
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TRIO_PUBLIC int
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trio_isinf
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TRIO_ARGS1((number),
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double number)
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{
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#if defined(TRIO_COMPILER_DECC) && !defined(__linux__)
|
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/*
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* DECC has an isinf() macro, but it works differently than that
|
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* of C99, so we use the fp_class() function instead.
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*/
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return ((fp_class(number) == FP_POS_INF)
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? 1
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: ((fp_class(number) == FP_NEG_INF) ? -1 : 0));
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|
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#elif defined(isinf)
|
|
/*
|
|
* C99 defines isinf() as a macro.
|
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*/
|
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return isinf(number)
|
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? ((number > 0.0) ? 1 : -1)
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: 0;
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|
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#elif defined(TRIO_COMPILER_MSVC) || defined(TRIO_COMPILER_BCB)
|
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/*
|
|
* Microsoft Visual C++ and Borland C++ Builder have an _fpclass()
|
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* function that can be used to detect infinity.
|
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*/
|
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return ((_fpclass(number) == _FPCLASS_PINF)
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? 1
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: ((_fpclass(number) == _FPCLASS_NINF) ? -1 : 0));
|
|
|
|
#elif defined(USE_IEEE_754)
|
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/*
|
|
* Examine IEEE 754 bit-pattern. Infinity must have a special exponent
|
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* pattern, and an empty mantissa.
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*/
|
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int has_mantissa;
|
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int is_special_quantity;
|
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is_special_quantity = trio_is_special_quantity(number, &has_mantissa);
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return (is_special_quantity && !has_mantissa)
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? ((number < 0.0) ? -1 : 1)
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: 0;
|
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|
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#else
|
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/*
|
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* Fallback solution.
|
|
*/
|
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int status;
|
|
|
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# if defined(TRIO_PLATFORM_UNIX)
|
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void (*signal_handler)(int) = signal(SIGFPE, SIG_IGN);
|
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# endif
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|
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double infinity = trio_pinf();
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|
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status = ((number == infinity)
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? 1
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: ((number == -infinity) ? -1 : 0));
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|
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# if defined(TRIO_PLATFORM_UNIX)
|
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signal(SIGFPE, signal_handler);
|
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# endif
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|
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return status;
|
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|
|
#endif
|
|
}
|
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|
|
#if 0
|
|
/* Temporary fix - this routine is not used anywhere */
|
|
/**
|
|
Check for finity.
|
|
|
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@param number An arbitrary floating-point number.
|
|
@return Boolean value indicating whether or not the number is a finite.
|
|
*/
|
|
TRIO_PUBLIC int
|
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trio_isfinite
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TRIO_ARGS1((number),
|
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double number)
|
|
{
|
|
#if defined(TRIO_COMPILER_SUPPORTS_C99) && defined(isfinite)
|
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/*
|
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* C99 defines isfinite() as a macro.
|
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*/
|
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return isfinite(number);
|
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|
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#elif defined(TRIO_COMPILER_MSVC) || defined(TRIO_COMPILER_BCB)
|
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/*
|
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* Microsoft Visual C++ and Borland C++ Builder use _finite().
|
|
*/
|
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return _finite(number);
|
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|
|
#elif defined(USE_IEEE_754)
|
|
/*
|
|
* Examine IEEE 754 bit-pattern. For finity we do not care about the
|
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* mantissa.
|
|
*/
|
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int dummy;
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|
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return (! trio_is_special_quantity(number, &dummy));
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|
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#else
|
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/*
|
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* Fallback solution.
|
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*/
|
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return ((trio_isinf(number) == 0) && (trio_isnan(number) == 0));
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|
|
#endif
|
|
}
|
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|
|
#endif
|
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|
|
/*
|
|
* 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
|