GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libm/src/ld80/e_acoshl.c Lines: 0 14 0.0 %
Date: 2017-11-13 Branches: 0 12 0.0 %

Line Branch Exec Source
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/* @(#)e_acosh.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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/* acoshl(x)
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 * Method :
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 *	Based on
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 *		acoshl(x) = logl [ x + sqrtl(x*x-1) ]
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 *	we have
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 *		acoshl(x) := logl(x)+ln2,	if x is large; else
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 *		acoshl(x) := logl(2x-1/(sqrtl(x*x-1)+x)) if x>2; else
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 *		acoshl(x) := log1pl(t+sqrtl(2.0*t+t*t)); where t=x-1.
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 *
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 * Special cases:
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 *	acoshl(x) is NaN with signal if x<1.
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 *	acoshl(NaN) is NaN without signal.
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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
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one	= 1.0,
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ln2	= 6.931471805599453094287e-01L; /* 0x3FFE, 0xB17217F7, 0xD1CF79AC */
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long double
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acoshl(long double x)
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{
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	long double t;
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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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	if(se<0x3fff || se & 0x8000) {	/* x < 1 */
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	    return (x-x)/(x-x);
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	} else if(se >=0x401d) {	/* x > 2**30 */
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	    if(se >=0x7fff) {		/* x is inf of NaN */
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		return x+x;
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	    } else
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		return logl(x)+ln2;	/* acoshl(huge)=logl(2x) */
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	} else if(((se-0x3fff)|i0|i1)==0) {
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	    return 0.0;			/* acosh(1) = 0 */
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	} else if (se > 0x4000) {	/* 2**28 > x > 2 */
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	    t=x*x;
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	    return logl(2.0*x-one/(x+sqrtl(t-one)));
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	} else {			/* 1<x<2 */
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	    t = x-one;
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	    return log1pl(t+sqrtl(2.0*t+t*t));
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	}
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}