1 /* Copyright (C) 2013-2021 Free Software Foundation, Inc.
2    This file is part of the GNU C Library
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Library General Public License as
6    published by the Free Software Foundation; either version 2 of the
7    License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Library General Public License for more details.
13 
14    You should have received a copy of the GNU Library General Public
15    License along with the GNU C Library; see the file COPYING.LIB.  If
16    not, see <https://www.gnu.org/licenses/>.  */
17 
18 /* ISA 2.07 provides fast GPR to FP instruction (mfvsr{d,wz}) which make
19    generic implementation faster.  Also disables for old ISAs that do not
20    have ceil/floor instructions.  */
21 #if defined(_ARCH_PWR8) || !defined(_ARCH_PWR5X)
22 # include <sysdeps/ieee754/ldbl-opt/s_modf.c>
23 #else
24 # include <math.h>
25 # include <math_ldbl_opt.h>
26 # include <libm-alias-double.h>
27 
28 double
__modf(double x,double * iptr)29 __modf (double x, double *iptr)
30 {
31   if (__builtin_isinf (x))
32     {
33       *iptr = x;
34       return copysign (0.0, x);
35     }
36   else if (__builtin_isnan (x))
37     {
38       *iptr = NAN;
39       return NAN;
40     }
41 
42   if (x >= 0.0)
43     {
44       *iptr = floor (x);
45       return copysign (x - *iptr, x);
46     }
47   else
48     {
49       *iptr = ceil (x);
50       return copysign (x - *iptr, x);
51     }
52 }
53 # ifndef __modf
54 libm_alias_double (__modf, modf)
55 #  if LONG_DOUBLE_COMPAT (libc, GLIBC_2_0)
56 compat_symbol (libc, __modf, modfl, GLIBC_2_0);
57 #  endif
58 # endif
59 #endif
60