sysdeps/ieee754/flt-32/s_asinhf.c

   1 /* s_asinhf.c -- float version of s_asinh.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 <float.h>
  17 #include <math.h>
  18 #include <math_private.h>
  19
  20 static const float
  21 one =  1.0000000000e+00, /* 0x3F800000 */
  22 ln2 =  6.9314718246e-01, /* 0x3f317218 */
  23 huge=  1.0000000000e+30;
  24
  25 float
  26 __asinhf(float x)
  27 {
  28         float w;
  29         int32_t hx,ix;
  30         GET_FLOAT_WORD(hx,x);
  31         ix = hx&0x7fffffff;
  32         if(__builtin_expect(ix< 0x38000000, 0)) {       /* |x|<2**-14 */
  33             math_check_force_underflow (x);
  34             if(huge+x>one) return x;    /* return x inexact except 0 */
  35         }
  36         if(__builtin_expect(ix>0x47000000, 0)) {        /* |x| > 2**14 */
  37             if(ix>=0x7f800000) return x+x;      /* x is inf or NaN */
  38             w = __ieee754_logf(fabsf(x))+ln2;
  39         } else {
  40             float xa = fabsf(x);
  41             if (ix>0x40000000) {        /* 2**14 > |x| > 2.0 */
  42                 w = __ieee754_logf(2.0f*xa+one/(__ieee754_sqrtf(xa*xa+one)+xa));
  43             } else {            /* 2.0 > |x| > 2**-14 */
  44                 float t = xa*xa;
  45                 w =__log1pf(xa+t/(one+__ieee754_sqrtf(one+t)));
  46             }
  47         }
  48         return __copysignf(w, x);
  49 }
  50 weak_alias (__asinhf, asinhf)