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/* s_frexpl.c -- long double version of s_frexp.c.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#if defined(LIBM_SCCS) && !defined(lint)
static char rcsid[] = "$NetBSD: $";
#endif
/*
* for non-zero x
* x = frexpl(arg,&exp);
* return a long double fp quantity x such that 0.5 <= |x| <1.0
* and the corresponding binary exponent "exp". That is
* arg = x*2^exp.
* If arg is inf, 0.0, or NaN, then frexpl(arg,&exp) returns arg
* with *exp=0.
*/
#include <float.h>
#include <math.h>
#include <math_private.h>
#include <libm-alias-ldouble.h>
static const long double
#if LDBL_MANT_DIG == 64
two65 = 3.68934881474191032320e+19L; /* 0x4040, 0x80000000, 0x00000000 */
#else
# error "Cannot handle this MANT_DIG"
#endif
long double __frexpl(long double x, int *eptr)
{
uint32_t se, hx, ix, lx;
GET_LDOUBLE_WORDS(se,hx,lx,x);
ix = 0x7fff&se;
*eptr = 0;
if(ix==0x7fff||((ix|hx|lx)==0)) return x + x; /* 0,inf,nan */
if (ix==0x0000) { /* subnormal */
x *= two65;
GET_LDOUBLE_EXP(se,x);
ix = se&0x7fff;
*eptr = -65;
}
*eptr += ix-16382;
se = (se & 0x8000) | 0x3ffe;
SET_LDOUBLE_EXP(x,se);
return x;
}
libm_alias_ldouble (__frexp, frexp)
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