1 | /* s_isnanl.c -- long double version for i387 of s_isnan.c. |
2 | */ |
3 | |
4 | /* |
5 | * ==================================================== |
6 | * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
7 | * |
8 | * Developed at SunPro, a Sun Microsystems, Inc. business. |
9 | * Permission to use, copy, modify, and distribute this |
10 | * software is freely granted, provided that this notice |
11 | * is preserved. |
12 | * ==================================================== |
13 | */ |
14 | |
15 | #if defined(LIBM_SCCS) && !defined(lint) |
16 | static char rcsid[] = "$NetBSD: $" ; |
17 | #endif |
18 | |
19 | /* |
20 | * isnanl(x) returns 1 is x is nan, else 0; |
21 | * no branching! |
22 | */ |
23 | |
24 | #include <math.h> |
25 | #include <math_private.h> |
26 | |
27 | int __isnanl(long double x) |
28 | { |
29 | int32_t se,hx,lx,pn; |
30 | GET_LDOUBLE_WORDS(se,hx,lx,x); |
31 | se = (se & 0x7fff) << 1; |
32 | /* Detect pseudo-normal numbers, i.e. exponent is non-zero and the top |
33 | bit of the significand is not set. */ |
34 | pn = (uint32_t)((~hx & 0x80000000) & (se|(-se)))>>31; |
35 | /* Clear the significand bit when computing mantissa. */ |
36 | lx |= hx & 0x7fffffff; |
37 | se |= (uint32_t)(lx|(-lx))>>31; |
38 | se = 0xfffe - se; |
39 | |
40 | return (int)(((uint32_t)(se)) >> 16) | pn; |
41 | } |
42 | hidden_def (__isnanl) |
43 | weak_alias (__isnanl, isnanl) |
44 | |