5980be9b3c
This work is based in part on code from NetBSD libm, libc and kernel. The library is partly public domain and partly BSD-style licensed.
49 lines
1.1 KiB
C
49 lines
1.1 KiB
C
/* w_log10f.c -- float version of w_log10.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 <sys/cdefs.h>
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#if defined(LIBM_SCCS) && !defined(lint)
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__RCSID("$NetBSD: w_log2f.c,v 1.1 2005/07/21 16:58:39 christos Exp $");
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#endif
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/*
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* wrapper log2f(X)
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*/
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#include "math.h"
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#include "math_private.h"
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float
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log2f(float x) /* wrapper log2f */
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{
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#ifdef _IEEE_LIBM
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return __ieee754_log2f(x);
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#else
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float z;
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z = __ieee754_log2f(x);
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if(_LIB_VERSION == _IEEE_ || isnanf(x)) return z;
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if(x<=(float)0.0) {
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if(x==(float)0.0)
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/* log2(0) */
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return (float)__kernel_standard((double)x,(double)x,148);
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else
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/* log2(x<0) */
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return (float)__kernel_standard((double)x,(double)x,149);
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} else
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return z;
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#endif
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}
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