1 /* s_frexpl.c -- long double version of s_frexp.c.
2 * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz.
3 */
4
5 /*
6 * ====================================================
7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8 *
9 * Developed at SunPro, a Sun Microsystems, Inc. business.
10 * Permission to use, copy, modify, and distribute this
11 * software is freely granted, provided that this notice
12 * is preserved.
13 * ====================================================
14 */
15
16 #if defined(LIBM_SCCS) && !defined(lint)
17 static char rcsid[] = "$NetBSD: $";
18 #endif
19
20 /*
21 * for non-zero x
22 * x = frexpq(arg,&exp);
23 * return a long double fp quantity x such that 0.5 <= |x| <1.0
24 * and the corresponding binary exponent "exp". That is
25 * arg = x*2^exp.
26 * If arg is inf, 0.0, or NaN, then frexpq(arg,&exp) returns arg
27 * with *exp=0.
28 */
29
30 #include "quadmath-imp.h"
31
32 static const __float128
33 two114 = 2.0769187434139310514121985316880384E+34Q; /* 0x4071000000000000, 0 */
34
frexpq(__float128 x,int * eptr)35 __float128 frexpq(__float128 x, int *eptr)
36 {
37 uint64_t hx, lx, ix;
38 GET_FLT128_WORDS64(hx,lx,x);
39 ix = 0x7fffffffffffffffULL&hx;
40 *eptr = 0;
41 if(ix>=0x7fff000000000000ULL||((ix|lx)==0)) return x + x;/* 0,inf,nan */
42 if (ix<0x0001000000000000ULL) { /* subnormal */
43 x *= two114;
44 GET_FLT128_MSW64(hx,x);
45 ix = hx&0x7fffffffffffffffULL;
46 *eptr = -114;
47 }
48 *eptr += (ix>>48)-16382;
49 hx = (hx&0x8000ffffffffffffULL) | 0x3ffe000000000000ULL;
50 SET_FLT128_MSW64(x,hx);
51 return x;
52 }
53