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#include <libm-alias-ldouble.h>
35
36static const long double
37#if LDBL_MANT_DIG == 64
38two65 = 3.68934881474191032320e+19L; /* 0x4040, 0x80000000, 0x00000000 */
39#else
40# error "Cannot handle this MANT_DIG"
41#endif
42
43
44long double __frexpl(long double x, int *eptr)
45{
46 uint32_t se, hx, ix, lx;
47 GET_LDOUBLE_WORDS(se,hx,lx,x);
48 ix = 0x7fff&se;
49 *eptr = 0;
50 if(ix==0x7fff||((ix|hx|lx)==0)) return x + x; /* 0,inf,nan */
51 if (ix==0x0000) { /* subnormal */
52 x *= two65;
53 GET_LDOUBLE_EXP(se,x);
54 ix = se&0x7fff;
55 *eptr = -65;
56 }
57 *eptr += ix-16382;
58 se = (se & 0x8000) | 0x3ffe;
59 SET_LDOUBLE_EXP(x,se);
60 return x;
61}
62libm_alias_ldouble (__frexp, frexp)
63