lib/libm/src/w_acosh.c

   1 /* @(#)w_acosh.c 5.1 93/09/24 */
   2 /*
   3  * ====================================================
   4  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   5  *
   6  * Developed at SunPro, a Sun Microsystems, Inc. business.
   7  * Permission to use, copy, modify, and distribute this
   8  * software is freely granted, provided that this notice
   9  * is preserved.
  10  * ====================================================
  11  */
  12
  13 #include <sys/cdefs.h>
  14 #if defined(LIBM_SCCS) && !defined(lint)
  15 __RCSID("$NetBSD: w_acosh.c,v 1.9 2002/05/26 22:01:59 wiz Exp $");
  16 #endif
  17
  18 /*
  19  * wrapper acosh(x)
  20  */
  21
  22 #include "math.h"
  23 #include "math_private.h"
  24
  25 double
  26 acosh(double x)         /* wrapper acosh */
  27 {
  28 #ifdef _IEEE_LIBM
  29         return __ieee754_acosh(x);
  30 #else
  31         double z;
  32         z = __ieee754_acosh(x);
  33         if(_LIB_VERSION == _IEEE_ || isnan(x)) return z;
  34         if(x<1.0) {
  35                 return __kernel_standard(x,x,29); /* acosh(x<1) */
  36         } else
  37             return z;
  38 #endif
  39 }