GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libm/src/ld80/e_atanhl.c Lines: 0 13 0.0 %
Date: 2017-11-13 Branches: 0 12 0.0 %

Line Branch Exec Source
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/* @(#)e_atanh.c 5.1 93/09/24 */
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/*
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 * ====================================================
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 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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 *
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 * Developed at SunPro, a Sun Microsystems, Inc. business.
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 * Permission to use, copy, modify, and distribute this
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 * software is freely granted, provided that this notice
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 * is preserved.
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 * ====================================================
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 */
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/* atanhl(x)
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 * Method :
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 *    1.Reduced x to positive by atanh(-x) = -atanh(x)
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 *    2.For x>=0.5
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 *                   1              2x                          x
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 *	atanhl(x) = --- * log(1 + -------) = 0.5 * log1p(2 * --------)
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 *                   2             1 - x                      1 - x
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 *
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 *	For x<0.5
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 *	atanhl(x) = 0.5*log1pl(2x+2x*x/(1-x))
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 *
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 * Special cases:
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 *	atanhl(x) is NaN if |x| > 1 with signal;
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 *	atanhl(NaN) is that NaN with no signal;
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 *	atanhl(+-1) is +-INF with signal.
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 *
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 */
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#include <math.h>
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#include "math_private.h"
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static const long double one = 1.0, huge = 1e4900L;
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static const long double zero = 0.0;
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long double
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atanhl(long double x)
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{
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	long double t;
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	int32_t ix;
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	u_int32_t se,i0,i1;
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	GET_LDOUBLE_WORDS(se,i0,i1,x);
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	ix = se&0x7fff;
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	if ((ix+((((i0&0x7fffffff)|i1)|(-((i0&0x7fffffff)|i1)))>>31))>0x3fff)
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	  /* |x|>1 */
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	    return (x-x)/(x-x);
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	if(ix==0x3fff)
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	    return x/zero;
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	if(ix<0x3fe3&&(huge+x)>zero) return x;	/* x<2**-28 */
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	SET_LDOUBLE_EXP(x,ix);
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	if(ix<0x3ffe) {		/* x < 0.5 */
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	    t = x+x;
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	    t = 0.5*log1pl(t+t*x/(one-x));
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	} else
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	    t = 0.5*log1pl((x+x)/(one-x));
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	if(se<=0x7fff) return t; else return -t;
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}