m68k: Reorganize log1p and significand implementations
[glibc.git] / sysdeps / ieee754 / dbl-64 / s_isnan.c
blob82723eeb8a7a1fb6565498af7d2812021386902a
1 /* @(#)s_isnan.c 5.1 93/09/24 */
2 /*
3 * ====================================================
4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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 * ====================================================
13 #if defined(LIBM_SCCS) && !defined(lint)
14 static char rcsid[] = "$NetBSD: s_isnan.c,v 1.8 1995/05/10 20:47:36 jtc Exp $";
15 #endif
18 * isnan(x) returns 1 is x is nan, else 0;
19 * no branching!
22 #include <math.h>
23 #include <math_private.h>
24 #include <ldbl-classify-compat.h>
25 #include <shlib-compat.h>
27 #undef __isnan
28 int
29 __isnan (double x)
31 int32_t hx, lx;
32 EXTRACT_WORDS (hx, lx, x);
33 hx &= 0x7fffffff;
34 hx |= (uint32_t) (lx | (-lx)) >> 31;
35 hx = 0x7ff00000 - hx;
36 return (int) (((uint32_t) hx) >> 31);
38 hidden_def (__isnan)
39 weak_alias (__isnan, isnan)
40 #ifdef NO_LONG_DOUBLE
41 # if LDBL_CLASSIFY_COMPAT && SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_23)
42 compat_symbol (libc, __isnan, __isnanl, GLIBC_2_0);
43 # endif
44 weak_alias (__isnan, isnanl)
45 #endif