1*1e651e1eSRoland Levillain 2*1e651e1eSRoland Levillain /* @(#)s_isnan.c 1.3 95/01/18 */ 3*1e651e1eSRoland Levillain /* 4*1e651e1eSRoland Levillain * ==================================================== 5*1e651e1eSRoland Levillain * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 6*1e651e1eSRoland Levillain * 7*1e651e1eSRoland Levillain * Developed at SunSoft, a Sun Microsystems, Inc. business. 8*1e651e1eSRoland Levillain * Permission to use, copy, modify, and distribute this 9*1e651e1eSRoland Levillain * software is freely granted, provided that this notice 10*1e651e1eSRoland Levillain * is preserved. 11*1e651e1eSRoland Levillain * ==================================================== 12*1e651e1eSRoland Levillain */ 13*1e651e1eSRoland Levillain 14*1e651e1eSRoland Levillain /* 15*1e651e1eSRoland Levillain * ieee_isnan(x) returns 1 is x is nan, else 0; 16*1e651e1eSRoland Levillain * no branching! 17*1e651e1eSRoland Levillain */ 18*1e651e1eSRoland Levillain 19*1e651e1eSRoland Levillain #include "fdlibm.h" 20*1e651e1eSRoland Levillain 21*1e651e1eSRoland Levillain #ifdef __STDC__ ieee_isnan(double x)22*1e651e1eSRoland Levillain int ieee_isnan(double x) 23*1e651e1eSRoland Levillain #else 24*1e651e1eSRoland Levillain int ieee_isnan(x) 25*1e651e1eSRoland Levillain double x; 26*1e651e1eSRoland Levillain #endif 27*1e651e1eSRoland Levillain { 28*1e651e1eSRoland Levillain int hx,lx; 29*1e651e1eSRoland Levillain hx = (__HI(x)&0x7fffffff); 30*1e651e1eSRoland Levillain lx = __LO(x); 31*1e651e1eSRoland Levillain hx |= (unsigned)(lx|(-lx))>>31; 32*1e651e1eSRoland Levillain hx = 0x7ff00000 - hx; 33*1e651e1eSRoland Levillain return ((unsigned)(hx))>>31; 34*1e651e1eSRoland Levillain } 35