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Length: 3173 (0xc65)
Types: TextFile
Notes: UNIX file
Names: »nan.h«
└─⟦7decd0fac⟧ Bits:30004155/disk4.imd SW95713I 386/ix Software Development System Rel. 2.0
└─⟦7decd0fac⟧ UNIX Filesystem
└─⟦this⟧ »sd/new/usr/include/nan.h«
/* Copyright (c) 1984 AT&T */
/* All Rights Reserved */
/* THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF AT&T */
/* The copyright notice above does not evidence any */
/* actual or intended publication of such source code. */
#ident "@(#)nan.h 2.3 - 88/05/27"
/* Handling of Not_a_Number's (only in IEEE floating-point standard) */
#if _IEEE
#if !i286 && !i386
typedef union
{
struct
{
unsigned sign : 1;
unsigned exponent :11;
unsigned bits:20;
unsigned fraction_low:32;
} inf_parts;
struct
{
unsigned sign : 1;
unsigned exponent :11;
unsigned qnan_bit : 1;
unsigned bits :19;
unsigned fraction_low: 32;
} nan_parts;
double d;
} dnan;
#endif
#if i386
typedef union
{
struct {
unsigned fraction_low:32;
unsigned bits:20;
unsigned exponent :11;
unsigned sign : 1;
} inf_parts;
struct {
unsigned fraction_low: 32;
unsigned bits :19;
unsigned qnan_bit : 1;
unsigned exponent :11;
unsigned sign : 1;
} nan_parts;
double d;
} dnan;
#endif
#if i286
/*
* i286 has 16 bit words and cannot address the fields that
* 32-bit machines can.
*/
typedef union
{
struct
{
unsigned long fraction_low;
unsigned short bits2;
unsigned bits1 :4;
unsigned exponent :11;
unsigned sign : 1;
} inf_parts;
struct
{
unsigned long fraction_low;
unsigned short bits2;
unsigned bits1 : 3;
unsigned qnan_bit : 1;
unsigned exponent :11;
unsigned sign : 1;
} nan_parts;
double d;
} dnan;
#endif
/* IsNANorINF checks that exponent of double == 2047 *
* i.e. that number is a NaN or an infinity */
#define IsNANorINF(X) (((dnan *)&(X))->nan_parts.exponent == 0x7ff)
/* IsINF must be used after IsNANorINF *
* has checked the exponent */
#ifndef i286
#define IsINF(X) (((dnan *)&(X))->inf_parts.bits == 0 && \
((dnan *)&(X))->inf_parts.fraction_low == 0)
#else
#define IsINF(X) (((dnan *)&(X))->inf_parts.bits1 == 0 && \
((dnan *)&(X))->inf_parts.bits2 == 0 && \
((dnan *)&(X))->inf_parts.fraction_low == 0)
#endif
/* IsPosNAN and IsNegNAN can be used *
* to check the sign of infinities too */
#define IsPosNAN(X) (((dnan *)&(X))->nan_parts.sign == 0)
#define IsNegNAN(X) (((dnan *)&(X))->nan_parts.sign == 1)
/* GETNaNPC gets the leftmost 32 bits *
* of the fraction part */
#ifndef i286
#define GETNaNPC(dval) (((dnan *)&(dval))->inf_parts.bits << 12 | \
((dnan *)&(dval))->nan_parts.fraction_low>> 20)
#else
#define GETNaNPC(dval) ((long) ((dnan *)&(dval))->inf_parts.bits1 << 28 | \
(long) ((dnan *)&(dval))->inf_parts.bits2 << 12 | \
((dnan *)&(dval))->nan_parts.fraction_low>> 20)
#endif
#define KILLFPE() (void) kill(getpid(), 8)
#define NaN(X) (((dnan *)&(X))->nan_parts.exponent == 0x7ff)
#define KILLNaN(X) if (NaN(X)) KILLFPE()
#else
typedef double dnan;
#define IsINF(X) 0
#define IsPINF(X) 0
#define IsNegNAN(X) 0
#define IsPosNAN(X) 0
#define IsNAN(X) 0
#define GETNaNPC 0L
#define NaN(X) 0
#define KILLNaN(X)
#endif