| /* |
| * ==================================================== |
| * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
| * |
| * Developed at SunPro, a Sun Microsystems, Inc. business. |
| * Permission to use, copy, modify, and distribute this |
| * software is freely granted, provided that this notice |
| * is preserved. |
| * ==================================================== |
| */ |
| |
| /* |
| FUNCTION |
| <<isnan>>, <<isnanf>>, <<isinf>>, <<isinff>>, <<finite>>, <<finitef>>---test for exceptional numbers |
| |
| INDEX |
| isnan |
| INDEX |
| isinf |
| INDEX |
| finite |
| |
| INDEX |
| isnanf |
| INDEX |
| isinff |
| INDEX |
| finitef |
| |
| ANSI_SYNOPSIS |
| #include <ieeefp.h> |
| int isnan(double <[arg]>); |
| int isinf(double <[arg]>); |
| int finite(double <[arg]>); |
| int isnanf(float <[arg]>); |
| int isinff(float <[arg]>); |
| int finitef(float <[arg]>); |
| |
| TRAD_SYNOPSIS |
| #include <ieeefp.h> |
| int isnan(<[arg]>) |
| double <[arg]>; |
| int isinf(<[arg]>) |
| double <[arg]>; |
| int finite(<[arg]>); |
| double <[arg]>; |
| int isnanf(<[arg]>); |
| float <[arg]>; |
| int isinff(<[arg]>); |
| float <[arg]>; |
| int finitef(<[arg]>); |
| float <[arg]>; |
| |
| |
| DESCRIPTION |
| These functions provide information on the floating-point |
| argument supplied. |
| |
| There are five major number formats: |
| o+ |
| o zero |
| A number which contains all zero bits. |
| o subnormal |
| A number with a zero exponent but a nonzero fraction. |
| o normal |
| A number with an exponent and a fraction. |
| o infinity |
| A number with an all 1's exponent and a zero fraction. |
| o NAN |
| A number with an all 1's exponent and a nonzero fraction. |
| |
| o- |
| |
| <<isnan>> returns 1 if the argument is a nan. <<isinf>> |
| returns 1 if the argument is infinity. <<finite>> returns 1 if the |
| argument is zero, subnormal or normal. |
| |
| Note that by the C99 standard, <<isnan>> and <<isinf>> are macros |
| taking any type of floating-point and are declared in |
| <<math.h>>. Newlib has chosen to declare these as macros in |
| <<math.h>> and as functions in <<ieeefp.h>>. |
| |
| The <<isnanf>>, <<isinff>> and <<finitef>> functions perform the same |
| operations as their <<isnan>>, <<isinf>> and <<finite>> |
| counterparts, but on single-precision floating-point numbers. |
| |
| QUICKREF |
| isnan - pure |
| QUICKREF |
| isinf - pure |
| QUICKREF |
| finite - pure |
| QUICKREF |
| isnan - pure |
| QUICKREF |
| isinf - pure |
| QUICKREF |
| finite - pure |
| */ |
| |
| /* |
| * __isnand(x) returns 1 is x is nan, else 0; |
| * no branching! |
| */ |
| |
| #include "fdlibm.h" |
| |
| #ifndef _DOUBLE_IS_32BITS |
| |
| int |
| _DEFUN (__isnand, (x), |
| double x) |
| { |
| __int32_t hx,lx; |
| EXTRACT_WORDS(hx,lx,x); |
| hx &= 0x7fffffff; |
| hx |= (__uint32_t)(lx|(-lx))>>31; |
| hx = 0x7ff00000 - hx; |
| return (int)(((__uint32_t)(hx))>>31); |
| } |
| |
| #endif /* _DOUBLE_IS_32BITS */ |