The Android Open Source Project | b07e1d9 | 2009-03-03 19:29:30 -0800 | [diff] [blame] | 1 | |
| 2 | /* @(#)s_isnan.c 1.3 95/01/18 */ |
| 3 | /* |
| 4 | * ==================================================== |
| 5 | * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
| 6 | * |
| 7 | * Developed at SunSoft, a Sun Microsystems, Inc. business. |
| 8 | * Permission to use, copy, modify, and distribute this |
| 9 | * software is freely granted, provided that this notice |
| 10 | * is preserved. |
| 11 | * ==================================================== |
| 12 | */ |
| 13 | |
| 14 | /* |
| 15 | * ieee_isnan(x) returns 1 is x is nan, else 0; |
| 16 | * no branching! |
| 17 | */ |
| 18 | |
| 19 | #include "fdlibm.h" |
| 20 | |
| 21 | #ifdef __STDC__ |
| 22 | int ieee_isnan(double x) |
| 23 | #else |
| 24 | int ieee_isnan(x) |
| 25 | double x; |
| 26 | #endif |
| 27 | { |
| 28 | int hx,lx; |
| 29 | hx = (__HI(x)&0x7fffffff); |
| 30 | lx = __LO(x); |
| 31 | hx |= (unsigned)(lx|(-lx))>>31; |
| 32 | hx = 0x7ff00000 - hx; |
| 33 | return ((unsigned)(hx))>>31; |
| 34 | } |