1 | #include "SDL_internal.h" |
2 | /* |
3 | * ==================================================== |
4 | * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
5 | * |
6 | * Developed at SunPro, a Sun Microsystems, Inc. business. |
7 | * Permission to use, copy, modify, and distribute this |
8 | * software is freely granted, provided that this notice |
9 | * is preserved. |
10 | * ==================================================== |
11 | */ |
12 | |
13 | /* |
14 | * isnan(x) returns 1 is x is nan, else 0; |
15 | * no branching! |
16 | */ |
17 | |
18 | #include "math.h" |
19 | #include "math_private.h" |
20 | |
21 | int __isnan(double x) |
22 | { |
23 | int32_t hx,lx; |
24 | EXTRACT_WORDS(hx,lx,x); |
25 | hx &= 0x7fffffff; |
26 | hx |= (u_int32_t)(lx|(-lx))>>31; |
27 | hx = 0x7ff00000 - hx; |
28 | return (int)(((u_int32_t)hx)>>31); |
29 | } |
30 | weak_alias(__isnan, isnan) |
31 | libm_hidden_def(__isnan) |
32 | |