1/* Round long double to integer away from zero.
2 Copyright (C) 1997-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
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 <https://www.gnu.org/licenses/>. */
18
19#define NO_MATH_REDIRECT
20#include <math.h>
21
22#include <math_private.h>
23#include <libm-alias-ldouble.h>
24#include <math-use-builtins.h>
25
26
27_Float128
28__roundl (_Float128 x)
29{
30#if USE_ROUNDL_BUILTIN
31 return __builtin_roundl (x);
32#else
33 /* Use generic implementation. */
34 int32_t j0;
35 uint64_t i1, i0;
36
37 GET_LDOUBLE_WORDS64 (i0, i1, x);
38 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
39 if (j0 < 48)
40 {
41 if (j0 < 0)
42 {
43 i0 &= 0x8000000000000000ULL;
44 if (j0 == -1)
45 i0 |= 0x3fff000000000000LL;
46 i1 = 0;
47 }
48 else
49 {
50 uint64_t i = 0x0000ffffffffffffLL >> j0;
51 if (((i0 & i) | i1) == 0)
52 /* X is integral. */
53 return x;
54
55 i0 += 0x0000800000000000LL >> j0;
56 i0 &= ~i;
57 i1 = 0;
58 }
59 }
60 else if (j0 > 111)
61 {
62 if (j0 == 0x4000)
63 /* Inf or NaN. */
64 return x + x;
65 else
66 return x;
67 }
68 else
69 {
70 uint64_t i = -1ULL >> (j0 - 48);
71 if ((i1 & i) == 0)
72 /* X is integral. */
73 return x;
74
75 uint64_t j = i1 + (1LL << (111 - j0));
76 if (j < i1)
77 i0 += 1;
78 i1 = j;
79 i1 &= ~i;
80 }
81
82 SET_LDOUBLE_WORDS64 (x, i0, i1);
83 return x;
84#endif /* ! USE_ROUNDL_BUILTIN */
85}
86libm_alias_ldouble (__round, round)
87