1/* s_frexpl.c -- long double version of s_frexp.c.
2 * Conversion to long double by Ulrich Drepper,
3 * Cygnus Support, drepper@cygnus.com.
4 */
5
6/*
7 * ====================================================
8 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
9 *
10 * Developed at SunPro, a Sun Microsystems, Inc. business.
11 * Permission to use, copy, modify, and distribute this
12 * software is freely granted, provided that this notice
13 * is preserved.
14 * ====================================================
15 */
16
17#if defined(LIBM_SCCS) && !defined(lint)
18static char rcsid[] = "$NetBSD: $";
19#endif
20
21/*
22 * for non-zero x
23 * x = frexpl(arg,&exp);
24 * return a long double fp quantity x such that 0.5 <= |x| <1.0
25 * and the corresponding binary exponent "exp". That is
26 * arg = x*2^exp.
27 * If arg is inf, 0.0, or NaN, then frexpl(arg,&exp) returns arg
28 * with *exp=0.
29 */
30
31#include <float.h>
32#include <math.h>
33#include <math_private.h>
34
35static const long double
36#if LDBL_MANT_DIG == 64
37two65 = 3.68934881474191032320e+19L; /* 0x4040, 0x80000000, 0x00000000 */
38#else
39# error "Cannot handle this MANT_DIG"
40#endif
41
42
43long double __frexpl(long double x, int *eptr)
44{
45 u_int32_t se, hx, ix, lx;
46 GET_LDOUBLE_WORDS(se,hx,lx,x);
47 ix = 0x7fff&se;
48 *eptr = 0;
49 if(ix==0x7fff||((ix|hx|lx)==0)) return x + x; /* 0,inf,nan */
50 if (ix==0x0000) { /* subnormal */
51 x *= two65;
52 GET_LDOUBLE_EXP(se,x);
53 ix = se&0x7fff;
54 *eptr = -65;
55 }
56 *eptr += ix-16382;
57 se = (se & 0x8000) | 0x3ffe;
58 SET_LDOUBLE_EXP(x,se);
59 return x;
60}
61weak_alias (__frexpl, frexpl)
62