GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libm/src/s_tanhf.c Lines: 0 17 0.0 %
Date: 2017-11-13 Branches: 0 12 0.0 %

Line Branch Exec Source
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/* s_tanhf.c -- float version of s_tanh.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 one=1.0, two=2.0, tiny = 1.0e-30;
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float
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tanhf(float x)
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{
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	float t,z;
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	int32_t jx,ix;
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	GET_FLOAT_WORD(jx,x);
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	ix = jx&0x7fffffff;
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    /* x is INF or NaN */
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	if(ix>=0x7f800000) {
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	    if (jx>=0) return one/x+one;    /* tanh(+-inf)=+-1 */
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	    else       return one/x-one;    /* tanh(NaN) = NaN */
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	}
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    /* |x| < 22 */
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	if (ix < 0x41b00000) {		/* |x|<22 */
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	    if (ix == 0)
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		return x;		/* x == +-0 */
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	    if (ix<0x24000000) 		/* |x|<2**-55 */
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		return x*(one+x);    	/* tanh(small) = small */
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	    if (ix>=0x3f800000) {	/* |x|>=1  */
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		t = expm1f(two*fabsf(x));
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		z = one - two/(t+two);
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	    } else {
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	        t = expm1f(-two*fabsf(x));
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	        z= -t/(t+two);
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	    }
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    /* |x| > 22, return +-1 */
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	} else {
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	    z = one - tiny;		/* raised inexact flag */
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	}
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	return (jx>=0)? z: -z;
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}