ref: 866d74c0c4bb50e85e9e8bb95140c10d409e53be
dir: /libmath/fdlibm/s_isnan.c/
/* derived from /netlib/fdlibm */ /* @(#)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 "fdlibm.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; }