1/* Round argument to nearest integral value according to current rounding
2 direction.
3 Copyright (C) 1997-2021 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
6 Jakub Jelinek <jj@ultra.linux.cz>, 1999.
7
8 The GNU C Library is free software; you can redistribute it and/or
9 modify it under the terms of the GNU Lesser General Public
10 License as published by the Free Software Foundation; either
11 version 2.1 of the License, or (at your option) any later version.
12
13 The GNU C Library is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
17
18 You should have received a copy of the GNU Lesser General Public
19 License along with the GNU C Library; if not, see
20 <https://www.gnu.org/licenses/>. */
21
22#include <fenv.h>
23#include <limits.h>
24#include <math.h>
25
26#include <math_private.h>
27#include <libm-alias-ldouble.h>
28#include <fix-fp-int-convert-overflow.h>
29
30static const _Float128 two112[2] =
31{
32 L(5.19229685853482762853049632922009600E+33), /* 0x406F000000000000, 0 */
33 L(-5.19229685853482762853049632922009600E+33) /* 0xC06F000000000000, 0 */
34};
35
36long long int
37__llrintl (_Float128 x)
38{
39 int32_t j0;
40 uint64_t i0,i1;
41 _Float128 w;
42 _Float128 t;
43 long long int result;
44 int sx;
45
46 GET_LDOUBLE_WORDS64 (i0, i1, x);
47 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
48 sx = i0 >> 63;
49 i0 &= 0x0000ffffffffffffLL;
50 i0 |= 0x0001000000000000LL;
51
52 if (j0 < (int32_t) (8 * sizeof (long long int)) - 1)
53 {
54#if defined FE_INVALID || defined FE_INEXACT
55 /* X < LLONG_MAX + 1 implied by J0 < 63. */
56 if (x > (_Float128) LLONG_MAX)
57 {
58 /* In the event of overflow we must raise the "invalid"
59 exception, but not "inexact". */
60 t = __nearbyintl (x);
61 feraiseexcept (t == LLONG_MAX ? FE_INEXACT : FE_INVALID);
62 }
63 else
64#endif
65 {
66 w = two112[sx] + x;
67 t = w - two112[sx];
68 }
69 GET_LDOUBLE_WORDS64 (i0, i1, t);
70 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
71 i0 &= 0x0000ffffffffffffLL;
72 i0 |= 0x0001000000000000LL;
73
74 if (j0 < 0)
75 result = 0;
76 else if (j0 <= 48)
77 result = i0 >> (48 - j0);
78 else
79 result = ((long long int) i0 << (j0 - 48)) | (i1 >> (112 - j0));
80 }
81 else
82 {
83 /* The number is too large. Unless it rounds to LLONG_MIN,
84 FE_INVALID must be raised and the return value is
85 unspecified. */
86#if defined FE_INVALID || defined FE_INEXACT
87 if (x < (_Float128) LLONG_MIN
88 && x > (_Float128) LLONG_MIN - 1)
89 {
90 /* If truncation produces LLONG_MIN, the cast will not raise
91 the exception, but may raise "inexact". */
92 t = __nearbyintl (x);
93 feraiseexcept (t == LLONG_MIN ? FE_INEXACT : FE_INVALID);
94 return LLONG_MIN;
95 }
96 else if (FIX_LDBL_LLONG_CONVERT_OVERFLOW && x != (_Float128) LLONG_MIN)
97 {
98 feraiseexcept (FE_INVALID);
99 return sx == 0 ? LLONG_MAX : LLONG_MIN;
100 }
101
102#endif
103 return (long long int) x;
104 }
105
106 return sx ? -result : result;
107}
108
109libm_alias_ldouble (__llrint, llrint)
110