1/* Round argument to nearest integral value according to current rounding
2 direction.
3 Copyright (C) 1997-2022 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
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 <https://www.gnu.org/licenses/>. */
19
20#include <fenv.h>
21#include <limits.h>
22#include <math.h>
23
24#include <math_private.h>
25#include <libm-alias-ldouble.h>
26#include <fix-fp-int-convert-overflow.h>
27
28static const _Float128 two112[2] =
29{
30 L(5.19229685853482762853049632922009600E+33), /* 0x406F000000000000, 0 */
31 L(-5.19229685853482762853049632922009600E+33) /* 0xC06F000000000000, 0 */
32};
33
34long long int
35__llrintl (_Float128 x)
36{
37 int32_t j0;
38 uint64_t i0,i1;
39 _Float128 w;
40 _Float128 t;
41 long long int result;
42 int sx;
43
44 GET_LDOUBLE_WORDS64 (i0, i1, x);
45 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
46 sx = i0 >> 63;
47 i0 &= 0x0000ffffffffffffLL;
48 i0 |= 0x0001000000000000LL;
49
50 if (j0 < (int32_t) (8 * sizeof (long long int)) - 1)
51 {
52#if defined FE_INVALID || defined FE_INEXACT
53 /* X < LLONG_MAX + 1 implied by J0 < 63. */
54 if (x > (_Float128) LLONG_MAX)
55 {
56 /* In the event of overflow we must raise the "invalid"
57 exception, but not "inexact". */
58 t = __nearbyintl (x);
59 feraiseexcept (t == LLONG_MAX ? FE_INEXACT : FE_INVALID);
60 }
61 else
62#endif
63 {
64 w = two112[sx] + x;
65 t = w - two112[sx];
66 }
67 GET_LDOUBLE_WORDS64 (i0, i1, t);
68 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
69 i0 &= 0x0000ffffffffffffLL;
70 i0 |= 0x0001000000000000LL;
71
72 if (j0 < 0)
73 result = 0;
74 else if (j0 <= 48)
75 result = i0 >> (48 - j0);
76 else
77 result = ((long long int) i0 << (j0 - 48)) | (i1 >> (112 - j0));
78 }
79 else
80 {
81 /* The number is too large. Unless it rounds to LLONG_MIN,
82 FE_INVALID must be raised and the return value is
83 unspecified. */
84#if defined FE_INVALID || defined FE_INEXACT
85 if (x < (_Float128) LLONG_MIN
86 && x > (_Float128) LLONG_MIN - 1)
87 {
88 /* If truncation produces LLONG_MIN, the cast will not raise
89 the exception, but may raise "inexact". */
90 t = __nearbyintl (x);
91 feraiseexcept (t == LLONG_MIN ? FE_INEXACT : FE_INVALID);
92 return LLONG_MIN;
93 }
94 else if (FIX_LDBL_LLONG_CONVERT_OVERFLOW && x != (_Float128) LLONG_MIN)
95 {
96 feraiseexcept (FE_INVALID);
97 return sx == 0 ? LLONG_MAX : LLONG_MIN;
98 }
99
100#endif
101 return (long long int) x;
102 }
103
104 return sx ? -result : result;
105}
106
107libm_alias_ldouble (__llrint, llrint)
108