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/* s_ilogbl.c -- long double version of s_ilogb.c.
* Conversion to long double by Ulrich Drepper,
* Cygnus Support, drepper@cygnus.com.
*/
/*
* ====================================================
* 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
/* ilogbl(long double x)
* return the binary exponent of non-zero x
* ilogbl(0) = 0x80000001
* ilogbl(inf/NaN) = 0x7fffffff (no signal is raised)
*/
#include "math.h"
#include "math_private.h"
#ifdef __STDC__
int __ilogbl(long double x)
#else
int __ilogbl(x)
long double x;
#endif
{
int32_t es,hx,lx,ix;
GET_LDOUBLE_EXP(es,x);
es &= 0x7fff;
if(es==0) {
GET_LDOUBLE_WORDS(es,hx,lx,x);
if((hx|lx)==0)
return 0x80000001; /* ilogbl(0) = 0x80000001 */
else /* subnormal x */
if(hx==0) {
for (ix = -16415; lx>0; lx<<=1) ix -=1;
} else {
for (ix = -16383; hx>0; hx<<=1) ix -=1;
}
return ix;
}
else if (es<0x7fff) return es-0x3fff;
else return 0x7fffffff;
}
weak_alias (__ilogbl, ilogbl)
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