1 /*
2 * ====================================================
3 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
4 *
5 * Developed at SunPro, a Sun Microsystems, Inc. business.
6 * Permission to use, copy, modify, and distribute this
7 * software is freely granted, provided that this notice
8 * is preserved.
9 * ====================================================
10 */
11
12 /*
13 * isnan(x) returns 1 is x is nan, else 0;
14 * no branching!
15 */
16
17 #include "math.h"
18 #include "math_private.h"
19
__isnan(double x)20 int __isnan(double x)
21 {
22 int32_t hx,lx;
23 EXTRACT_WORDS(hx,lx,x);
24 hx &= 0x7fffffff;
25 hx |= (u_int32_t)(lx|(-lx))>>31;
26 hx = 0x7ff00000 - hx;
27 return (int)(((u_int32_t)hx)>>31);
28 }
29 libm_hidden_def(__isnan)
30