| /* @(#)s_isnan.c 5.1 93/09/24 */ |
| /* |
| * ==================================================== |
| * 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. |
| * ==================================================== |
| */ |
| |
| #if defined(LIBM_SCCS) && !defined(lint) |
| static char rcsid[] = "$NetBSD: s_isnan.c,v 1.8 1995/05/10 20:47:36 jtc Exp $"; |
| #endif |
| |
| /* |
| * isnan(x) returns 1 is x is nan, else 0; |
| * no branching! |
| */ |
| |
| #include <math.h> |
| #include <math_private.h> |
| |
| #undef __isnan |
| int |
| __isnan (double x) |
| { |
| int32_t hx, lx; |
| EXTRACT_WORDS (hx, lx, x); |
| hx &= 0x7fffffff; |
| hx |= (u_int32_t) (lx | (-lx)) >> 31; |
| hx = 0x7ff00000 - hx; |
| return (int) (((u_int32_t) hx) >> 31); |
| } |
| hidden_def (__isnan) |
| weak_alias (__isnan, isnan) |
| #ifdef NO_LONG_DOUBLE |
| strong_alias (__isnan, __isnanl) |
| weak_alias (__isnan, isnanl) |
| #endif |
