1/* Round long double to integer away from zero.
2 Copyright (C) 1997-2016 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
19
20#include <math.h>
21
22#include <math_private.h>
23
24
25long double
26__roundl (long double x)
27{
28 int32_t j0;
29 u_int32_t se, i1, i0;
30
31 GET_LDOUBLE_WORDS (se, i0, i1, x);
32 j0 = (se & 0x7fff) - 0x3fff;
33 if (j0 < 31)
34 {
35 if (j0 < 0)
36 {
37 se &= 0x8000;
38 i0 = i1 = 0;
39 if (j0 == -1)
40 {
41 se |= 0x3fff;
42 i0 = 0x80000000;
43 }
44 }
45 else
46 {
47 u_int32_t i = 0x7fffffff >> j0;
48 if (((i0 & i) | i1) == 0)
49 /* X is integral. */
50 return x;
51
52 u_int32_t j = i0 + (0x40000000 >> j0);
53 if (j < i0)
54 se += 1;
55 i0 = (j & ~i) | 0x80000000;
56 i1 = 0;
57 }
58 }
59 else if (j0 > 62)
60 {
61 if (j0 == 0x4000)
62 /* Inf or NaN. */
63 return x + x;
64 else
65 return x;
66 }
67 else
68 {
69 u_int32_t i = 0xffffffff >> (j0 - 31);
70 if ((i1 & i) == 0)
71 /* X is integral. */
72 return x;
73
74 u_int32_t j = i1 + (1 << (62 - j0));
75 if (j < i1)
76 {
77 u_int32_t k = i0 + 1;
78 if (k < i0)
79 {
80 se += 1;
81 k |= 0x80000000;
82 }
83 i0 = k;
84 }
85 i1 = j;
86 i1 &= ~i;
87 }
88
89 SET_LDOUBLE_WORDS (x, se, i0, i1);
90 return x;
91}
92weak_alias (__roundl, roundl)
93