GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libm/src/e_acosl.c Lines: 0 36 0.0 %
Date: 2017-11-13 Branches: 0 14 0.0 %

Line Branch Exec Source
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/*	$OpenBSD: e_acosl.c,v 1.1 2008/12/09 20:00:35 martynas Exp $	*/
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/* @(#)e_acos.c 1.3 95/01/18 */
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/* FreeBSD: head/lib/msun/src/e_acos.c 176451 2008-02-22 02:30:36Z das */
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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 SunSoft, 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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/*
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 * See comments in e_acos.c.
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 * Converted to long double by David Schultz <das@FreeBSD.ORG>.
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 * Adapted for OpenBSD by Martynas Venckus <martynas@openbsd.org>.
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 */
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#include <float.h>
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#include <math.h>
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#include "invtrig.h"
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#include "math_private.h"
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#ifdef EXT_IMPLICIT_NBIT
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#define	LDBL_NBIT	0
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#else /* EXT_IMPLICIT_NBIT */
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#define	LDBL_NBIT	0x80000000
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#endif /* EXT_IMPLICIT_NBIT */
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static const long double
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one=  1.00000000000000000000e+00;
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#if defined(__amd64__) || defined(__i386__)
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/* XXX Work around the fact that gcc truncates long double constants on i386 */
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static volatile double
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pi1 =  3.14159265358979311600e+00,	/*  0x1.921fb54442d18p+1  */
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pi2 =  1.22514845490862001043e-16;	/*  0x1.1a80000000000p-53 */
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#define	pi	((long double)pi1 + pi2)
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#else
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static const long double
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pi =  3.14159265358979323846264338327950280e+00L;
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#endif
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long double
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acosl(long double x)
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{
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	union {
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		long double e;
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		struct ieee_ext bits;
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	} u;
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	long double z,p,q,r,w,s,c,df;
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	int16_t expsign, expt;
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	u.e = x;
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	expsign = (u.bits.ext_sign << 15) | u.bits.ext_exp;
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	expt = expsign & 0x7fff;
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	if(expt >= BIAS) {	/* |x| >= 1 */
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	    if(expt==BIAS && ((u.bits.ext_frach&~LDBL_NBIT)
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#ifdef EXT_FRACHMBITS
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		| u.bits.ext_frachm
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#endif /* EXT_FRACHMBITS */
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#ifdef EXT_FRACLMBITS
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		| u.bits.ext_fraclm
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#endif /* EXT_FRACLMBITS */
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		| u.bits.ext_fracl)==0) {
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		if (expsign>0) return 0.0;	/* acos(1) = 0  */
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		else return pi+2.0*pio2_lo;	/* acos(-1)= pi */
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	    }
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	    return (x-x)/(x-x);		/* acos(|x|>1) is NaN */
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	}
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	if(expt<BIAS-1) {	/* |x| < 0.5 */
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	    if(expt<ACOS_CONST) return pio2_hi+pio2_lo;/*x tiny: acosl=pi/2*/
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	    z = x*x;
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	    p = P(z);
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	    q = Q(z);
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	    r = p/q;
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	    return pio2_hi - (x - (pio2_lo-x*r));
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	} else  if (expsign<0) {	/* x < -0.5 */
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	    z = (one+x)*0.5;
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	    p = P(z);
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	    q = Q(z);
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	    s = sqrtl(z);
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	    r = p/q;
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	    w = r*s-pio2_lo;
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	    return pi - 2.0*(s+w);
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	} else {			/* x > 0.5 */
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	    z = (one-x)*0.5;
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	    s = sqrtl(z);
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	    u.e = s;
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	    u.bits.ext_fracl = 0;
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#ifdef EXT_FRACLMBITS
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	    u.bits.ext_fraclm = 0;
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#endif /* EXT_FRACLMBITS */
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	    df = u.e;
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	    c  = (z-df*df)/(s+df);
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	    p = P(z);
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	    q = Q(z);
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	    r = p/q;
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	    w = r*s+c;
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	    return 2.0*(df+w);
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	}
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}