lib/libm/src/w_logf.c

   1 /* w_logf.c -- float version of w_log.c.
   2  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
   3  */
   4
   5 /*
   6  * ====================================================
   7  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   8  *
   9  * Developed at SunPro, a Sun Microsystems, Inc. business.
  10  * Permission to use, copy, modify, and distribute this
  11  * software is freely granted, provided that this notice
  12  * is preserved.
  13  * ====================================================
  14  */
  15
  16 #include <sys/cdefs.h>
  17 #if defined(LIBM_SCCS) && !defined(lint)
  18 __RCSID("$NetBSD: w_logf.c,v 1.7 2007/08/20 16:01:40 drochner Exp $");
  19 #endif
  20
  21 /*
  22  * wrapper logf(x)
  23  */
  24
  25 #include "namespace.h"
  26 #include "math.h"
  27 #include "math_private.h"
  28
  29 #ifdef __weak_alias
  30 __weak_alias(logf, _logf)
  31 #endif
  32
  33 float
  34 logf(float x)           /* wrapper logf */
  35 {
  36 #ifdef _IEEE_LIBM
  37         return __ieee754_logf(x);
  38 #else
  39         float z;
  40         z = __ieee754_logf(x);
  41         if(_LIB_VERSION == _IEEE_ || isnanf(x) || x > (float)0.0) return z;
  42         if(x==(float)0.0)
  43             /* logf(0) */
  44             return (float)__kernel_standard((double)x,(double)x,116);
  45         else
  46             /* logf(x<0) */
  47             return (float)__kernel_standard((double)x,(double)x,117);
  48 #endif
  49 }