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 int
35__lrintl (_Float128 x)
36{
37 int32_t j0;
38 uint64_t i0,i1;
39 _Float128 w;
40 _Float128 t;
41 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 int)) - 1)
51 {
52 if (j0 < 48)
53 {
54#if defined FE_INVALID || defined FE_INEXACT
55 /* X < LONG_MAX + 1 implied by J0 < 31. */
56 if (sizeof (long int) == 4
57 && x > (_Float128) LONG_MAX)
58 {
59 /* In the event of overflow we must raise the "invalid"
60 exception, but not "inexact". */
61 t = __nearbyintl (x);
62 feraiseexcept (t == LONG_MAX ? FE_INEXACT : FE_INVALID);
63 }
64 else
65#endif
66 {
67 w = two112[sx] + x;
68 t = w - two112[sx];
69 }
70 GET_LDOUBLE_WORDS64 (i0, i1, t);
71 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
72 i0 &= 0x0000ffffffffffffLL;
73 i0 |= 0x0001000000000000LL;
74
75 result = (j0 < 0 ? 0 : i0 >> (48 - j0));
76 }
77 else if (j0 >= 112)
78 result = ((long int) i0 << (j0 - 48)) | (i1 << (j0 - 112));
79 else
80 {
81#if defined FE_INVALID || defined FE_INEXACT
82 /* X < LONG_MAX + 1 implied by J0 < 63. */
83 if (sizeof (long int) == 8
84 && x > (_Float128) LONG_MAX)
85 {
86 /* In the event of overflow we must raise the "invalid"
87 exception, but not "inexact". */
88 t = __nearbyintl (x);
89 feraiseexcept (t == LONG_MAX ? FE_INEXACT : FE_INVALID);
90 }
91 else
92#endif
93 {
94 w = two112[sx] + x;
95 t = w - two112[sx];
96 }
97 GET_LDOUBLE_WORDS64 (i0, i1, t);
98 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
99 i0 &= 0x0000ffffffffffffLL;
100 i0 |= 0x0001000000000000LL;
101
102 if (j0 == 48)
103 result = (long int) i0;
104 else
105 result = ((long int) i0 << (j0 - 48)) | (i1 >> (112 - j0));
106 }
107 }
108 else
109 {
110 /* The number is too large. Unless it rounds to LONG_MIN,
111 FE_INVALID must be raised and the return value is
112 unspecified. */
113#if defined FE_INVALID || defined FE_INEXACT
114 if (x < (_Float128) LONG_MIN
115 && x > (_Float128) LONG_MIN - 1)
116 {
117 /* If truncation produces LONG_MIN, the cast will not raise
118 the exception, but may raise "inexact". */
119 t = __nearbyintl (x);
120 feraiseexcept (t == LONG_MIN ? FE_INEXACT : FE_INVALID);
121 return LONG_MIN;
122 }
123 else if (FIX_LDBL_LONG_CONVERT_OVERFLOW && x != (_Float128) LONG_MIN)
124 {
125 feraiseexcept (FE_INVALID);
126 return sx == 0 ? LONG_MAX : LONG_MIN;
127 }
128
129#endif
130 return (long int) x;
131 }
132
133 return sx ? -result : result;
134}
135
136libm_alias_ldouble (__lrint, lrint)
137