/* @(#)s_isnan.c 1.3 95/01/18 */ /* * ==================================================== * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. * * Developed at SunSoft, a Sun Microsystems, Inc. business. * Permission to use, copy, modify, and distribute this * software is freely granted, provided that this notice * is preserved. * ==================================================== */ /* * isnan(x) returns 1 is x is nan, else 0; * no branching! */ #include "math.h" int isnan(double x) { int hx, lx; hx = (__HI(x) & 0x7fffffff); lx = __LO(x); hx |= (unsigned)(lx | (-lx)) >> 31; hx = 0x7ff00000 - hx; return ((unsigned)(hx)) >> 31; }