]>
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1 /* Round long double value to long int.
2 Copyright (C) 1997-2021 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
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>
29 __lroundl (long double x
)
36 GET_LDOUBLE_WORDS (se
, i0
, i1
, x
);
37 j0
= (se
& 0x7fff) - 0x3fff;
38 sign
= (se
& 0x8000) != 0 ? -1 : 1;
43 return j0
< -1 ? 0 : sign
;
46 uint32_t j
= i0
+ (0x40000000 >> j0
);
54 result
= j
>> (31 - j0
);
56 if (sizeof (long int) == 4
58 && result
== LONG_MIN
)
59 /* Rounding brought the value out of range. */
60 feraiseexcept (FE_INVALID
);
64 else if (j0
< (int32_t) (8 * sizeof (long int)) - 1)
67 result
= ((long int) i0
<< (j0
- 31)) | (i1
<< (j0
- 63));
70 uint32_t j
= i1
+ (0x80000000 >> (j0
- 31));
71 unsigned long int ures
= i0
;
80 result
= (ures
<< (j0
- 31)) | (j
>> (63 - j0
));
82 if (sizeof (long int) == 8
84 && result
== LONG_MIN
)
85 /* Rounding brought the value out of range. */
86 feraiseexcept (FE_INVALID
);
93 /* The number is too large. Unless it rounds to LONG_MIN,
94 FE_INVALID must be raised and the return value is
97 if (sizeof (long int) == 4
98 && x
<= (long double) LONG_MIN
- 0.5L)
100 /* If truncation produces LONG_MIN, the cast will not raise
101 the exception, but may raise "inexact". */
102 feraiseexcept (FE_INVALID
);
109 return sign
* result
;
112 libm_alias_ldouble (__lround
, lround
)