w_log.c

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/* @(#)w_log.c 1.3 95/01/18 */
/*
 * ====================================================
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
 *
 * Developed at SunSoft, a Sun Microsystems, Inc. business.
 * Permission to use, copy, modify, and distribute this
 * software is freely granted, provided that this notice 
 * is preserved.
 * ====================================================
 */

/*
 * wrapper log(x)
 */

#include "fdlibm.h"


#ifdef __STDC__
    double log(double x)        /* wrapper log */
#else
    double log(x)           /* wrapper log */
    double x;
#endif
{
#ifdef _IEEE_LIBM
    return __ieee754_log(x);
#else
    double z;
    z = __ieee754_log(x);
    if(_LIB_VERSION == _IEEE_ || isnan(x) || x > 0.0) return z;
    if(x==0.0)
        return __kernel_standard(x,x,16); /* log(0) */
    else 
        return __kernel_standard(x,x,17); /* log(x<0) */
#endif
}