GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libm/src/e_asinf.c Lines: 0 31 0.0 %
Date: 2017-11-07 Branches: 0 14 0.0 %

Line Branch Exec Source
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/* e_asinf.c -- float version of e_asin.c.
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 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
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 */
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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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#include "math.h"
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#include "math_private.h"
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static const float
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one =  1.0000000000e+00, /* 0x3F800000 */
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huge =  1.000e+30,
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pio2_hi =  1.5707962513e+00, /* 0x3fc90fda */
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pio2_lo =  7.5497894159e-08, /* 0x33a22168 */
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pio4_hi =  7.8539818525e-01, /* 0x3f490fdb */
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	/* coefficient for R(x^2) */
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pS0 =  1.6666667163e-01, /* 0x3e2aaaab */
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pS1 = -3.2556581497e-01, /* 0xbea6b090 */
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pS2 =  2.0121252537e-01, /* 0x3e4e0aa8 */
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pS3 = -4.0055535734e-02, /* 0xbd241146 */
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pS4 =  7.9153501429e-04, /* 0x3a4f7f04 */
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pS5 =  3.4793309169e-05, /* 0x3811ef08 */
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qS1 = -2.4033949375e+00, /* 0xc019d139 */
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qS2 =  2.0209457874e+00, /* 0x4001572d */
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qS3 = -6.8828397989e-01, /* 0xbf303361 */
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qS4 =  7.7038154006e-02; /* 0x3d9dc62e */
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float
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asinf(float x)
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{
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	float t,w,p,q,c,r,s;
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	int32_t hx,ix;
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	GET_FLOAT_WORD(hx,x);
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	ix = hx&0x7fffffff;
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	if(ix==0x3f800000) {
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		/* asin(1)=+-pi/2 with inexact */
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	    return x*pio2_hi+x*pio2_lo;
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	} else if(ix> 0x3f800000) {	/* |x|>= 1 */
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	    return (x-x)/(x-x);		/* asin(|x|>1) is NaN */
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	} else if (ix<0x3f000000) {	/* |x|<0.5 */
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	    if(ix<0x32000000) {		/* if |x| < 2**-27 */
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		if(huge+x>one) return x;/* return x with inexact if x!=0*/
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	    }
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	    t = x*x;
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	    p = t*(pS0+t*(pS1+t*(pS2+t*(pS3+t*(pS4+t*pS5)))));
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	    q = one+t*(qS1+t*(qS2+t*(qS3+t*qS4)));
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	    w = p/q;
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	    return x+x*w;
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	}
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	/* 1> |x|>= 0.5 */
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	w = one-fabsf(x);
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	t = w*(float)0.5;
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	p = t*(pS0+t*(pS1+t*(pS2+t*(pS3+t*(pS4+t*pS5)))));
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	q = one+t*(qS1+t*(qS2+t*(qS3+t*qS4)));
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	s = sqrtf(t);
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	if(ix>=0x3F79999A) { 	/* if |x| > 0.975 */
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	    w = p/q;
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	    t = pio2_hi-((float)2.0*(s+s*w)-pio2_lo);
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	} else {
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	    int32_t iw;
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	    w  = s;
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	    GET_FLOAT_WORD(iw,w);
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	    SET_FLOAT_WORD(w,iw&0xfffff000);
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	    c  = (t-w*w)/(s+w);
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	    r  = p/q;
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	    p  = (float)2.0*s*r-(pio2_lo-(float)2.0*c);
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	    q  = pio4_hi-(float)2.0*w;
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	    t  = pio4_hi-(p-q);
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	}
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	if(hx>0) return t; else return -t;
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}
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DEF_STD(asinf);