1 | /* @(#)s_isnan.c 5.1 93/09/24 */ |
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 | #include <shlib-compat.h> |
21 | #include <stdint.h> |
22 | |
23 | #undef __isnan |
24 | int __isnan(double x) |
25 | { |
26 | int64_t hx; |
27 | EXTRACT_WORDS64(hx,x); |
28 | hx &= UINT64_C(0x7fffffffffffffff); |
29 | hx = UINT64_C(0x7ff0000000000000) - hx; |
30 | return (int)(((uint64_t)hx)>>63); |
31 | } |
32 | hidden_def (__isnan) |
33 | weak_alias (__isnan, isnan) |
34 | #ifdef NO_LONG_DOUBLE |
35 | # if defined LDBL_CLASSIFY_COMPAT && SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_23) |
36 | compat_symbol (libc, __isnan, __isnanl, GLIBC_2_0); |
37 | # endif |
38 | weak_alias (__isnan, isnanl) |
39 | #endif |
40 | |