1 /* Copyright (C) 2011-2016 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3    Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <http://www.gnu.org/licenses/>.  */
18 
19 #include <math.h>
20 #include "math_private.h"
21 
22 #if !defined __NO_LONG_DOUBLE_MATH
23 /* wrapper powl */
24 long double
powl(long double x,long double y)25 powl (long double x, long double y)
26 {
27 #if defined(__UCLIBC_HAS_FENV__)
28 	long double z = (long double) __ieee754_pow ((double) x, (double) y);
29   if (__builtin_expect (!isfinite (z), 0))
30     {
31       if (_LIB_VERSION != _IEEE_)
32 	{
33 	  if (isnan (x))
34 	    {
35 	      if (y == 0.0L)
36 		/* pow(NaN,0.0) */
37 		return __kernel_standard_l (x, y, 242);
38 	    }
39 	  else if (isfinite (x) && isfinite (y))
40 	    {
41 	      if (isnan (z))
42 		/* pow neg**non-int */
43 		return __kernel_standard_l (x, y, 224);
44 	      else if (x == 0.0L && y < 0.0L)
45 		{
46 		  if (signbit (x) && signbit (z))
47 		    /* pow(-0.0,negative) */
48 		    return __kernel_standard_l (x, y, 223);
49 		  else
50 		    /* pow(+0.0,negative) */
51 		    return __kernel_standard_l (x, y, 243);
52 		}
53 	      else
54 		/* pow overflow */
55 		return __kernel_standard_l (x, y, 221);
56 	    }
57 	}
58     }
59   else if (__builtin_expect (z == 0.0L, 0) && isfinite (x) && isfinite (y)
60 	   && _LIB_VERSION != _IEEE_)
61     {
62       if (x == 0.0L)
63 	{
64 	  if (y == 0.0L)
65 	    /* pow(0.0,0.0) */
66 	    return __kernel_standard_l (x, y, 220);
67 	}
68       else
69 	/* pow underflow */
70 	return __kernel_standard_l (x, y, 222);
71     }
72 
73 	return z;
74 # else
75 	return (long double) __ieee754_pow ((double) x, (double) y);
76 # endif /* __UCLIBC_HAS_FENV__ */
77 }
78 #endif /* __NO_LONG_DOUBLE_MATH */
79