1 /* Round argument to nearest integral value according to current rounding
3 Copyright (C) 1997-2024 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
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.
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.
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/>. */
24 #include <math_private.h>
25 #include <libm-alias-ldouble.h>
27 static const long double two63
[2] =
29 9.223372036854775808000000e+18, /* 0x403E, 0x00000000, 0x00000000 */
30 -9.223372036854775808000000e+18 /* 0xC03E, 0x00000000, 0x00000000 */
35 __lrintl (long double x
)
44 GET_LDOUBLE_WORDS (se
, i0
, i1
, x
);
47 j0
= (se
& 0x7fff) - 0x3fff;
51 #if defined FE_INVALID || defined FE_INEXACT
52 /* X < LONG_MAX + 1 implied by J0 < 31. */
53 if (sizeof (long int) == 4
54 && x
> (long double) LONG_MAX
)
56 /* In the event of overflow we must raise the "invalid"
57 exception, but not "inexact". */
59 feraiseexcept (t
== LONG_MAX
? FE_INEXACT
: FE_INVALID
);
67 GET_LDOUBLE_WORDS (se
, i0
, i1
, t
);
68 j0
= (se
& 0x7fff) - 0x3fff;
70 result
= (j0
< 0 ? 0 : i0
>> (31 - j0
));
72 else if (j0
< (int32_t) (8 * sizeof (long int)) - 1)
75 result
= ((long int) i0
<< (j0
- 31)) | (i1
<< (j0
- 63));
78 #if defined FE_INVALID || defined FE_INEXACT
79 /* X < LONG_MAX + 1 implied by J0 < 63. */
80 if (sizeof (long int) == 8
81 && x
> (long double) LONG_MAX
)
83 /* In the event of overflow we must raise the "invalid"
84 exception, but not "inexact". */
86 feraiseexcept (t
== LONG_MAX
? FE_INEXACT
: FE_INVALID
);
94 GET_LDOUBLE_WORDS (se
, i0
, i1
, t
);
95 j0
= (se
& 0x7fff) - 0x3fff;
98 result
= (long int) i0
;
100 result
= ((long int) i0
<< (j0
- 31)) | (i1
>> (63 - j0
));
105 /* The number is too large. Unless it rounds to LONG_MIN,
106 FE_INVALID must be raised and the return value is
108 #if defined FE_INVALID || defined FE_INEXACT
109 if (sizeof (long int) == 4
110 && x
< (long double) LONG_MIN
111 && x
> (long double) LONG_MIN
- 1.0L)
113 /* If truncation produces LONG_MIN, the cast will not raise
114 the exception, but may raise "inexact". */
115 t
= __nearbyintl (x
);
116 feraiseexcept (t
== LONG_MIN
? FE_INEXACT
: FE_INVALID
);
123 return sx
? -result
: result
;
126 libm_alias_ldouble (__lrint
, lrint
)