//===========================================================================
//
//      sf_asinh.c
//
//      Part of the standard mathematical function library
//
//===========================================================================
// ####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 2012 Free Software Foundation, Inc.
//
// eCos is free software; you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation; either version 2 or (at your option) any later
// version.
//
// eCos is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License
// along with eCos; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
//
// As a special exception, if other files instantiate templates or use
// macros or inline functions from this file, or you compile this file
// and link it with other works to produce a work based on this file,
// this file does not by itself cause the resulting work to be covered by
// the GNU General Public License. However the source code for this file
// must still be made available in accordance with section (3) of the GNU
// General Public License v2.
//
// This exception does not invalidate any other reasons why a work based
// on this file might be covered by the GNU General Public License.
// -------------------------------------------
// ####ECOSGPLCOPYRIGHTEND####
//===========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):
// Contributors: visar, ilijak
// Date:        2012-03-08
// Purpose:
// Description:
// Usage:
//
//####DESCRIPTIONEND####
//
//===========================================================================

// CONFIGURATION

#include <pkgconf/libm.h>   // Configuration header

// Include the Math library?
#ifdef CYGPKG_LIBM

// Derived from code with the following copyright


/* sf_asinh.c -- float version of s_asinh.c.
 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@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.
 * ====================================================
 */

#include "mathincl/fdlibm.h"

#ifdef __STDC__
static const float
#else
static float
#endif
one =  1.0000000000e+00, /* 0x3F800000 */
ln2 =  6.9314718246e-01, /* 0x3f317218 */
huge=  1.0000000000e+30;

#ifdef __STDC__
	float asinhf(float x)
#else
	float asinhf(x)
	float x;
#endif
{
	float t,w;
	__int32_t hx,ix;
	hx = CYG_LIBM_WORD(x);
	ix = hx&0x7fffffff;
	if(!FLT_UWORD_IS_FINITE(ix)) return x+x;	/* x is inf or NaN */
	if(ix< 0x31800000) {	/* |x|<2**-28 */
	    if(huge+x>one) return x;	/* return x inexact except 0 */
	}
	if(ix>0x4d800000) {	/* |x| > 2**28 */
	    w = __ieee754_logf(fabsf(x))+ln2;
	} else if (ix>0x40000000) {	/* 2**28 > |x| > 2.0 */
	    t = fabsf(x);
	    w = __ieee754_logf((float)2.0*t+one/(__ieee754_sqrtf(x*x+one)+t));
	} else {		/* 2.0 > |x| > 2**-28 */
	    t = x*x;
	    w =log1pf(fabsf(x)+t/(one+__ieee754_sqrtf(one+t)));
	}
	if(hx>0) return w; else return -w;
}

#endif // ifdef CYGPKG_LIBM

// EOF sf_asinh.c
