1 /* Round long double value to long int.
2 Copyright (C) 1997-2024 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
23 #include <math_private.h>
24 #include <libm-alias-ldouble.h>
25 #include <fix-fp-int-convert-overflow.h>
28 __lroundl (_Float128 x
)
35 GET_LDOUBLE_WORDS64 (i0
, i1
, x
);
36 j0
= ((i0
>> 48) & 0x7fff) - 0x3fff;
37 sign
= (i0
& 0x8000000000000000ULL
) != 0 ? -1 : 1;
38 i0
&= 0x0000ffffffffffffLL
;
39 i0
|= 0x0001000000000000LL
;
41 if (j0
< (int32_t) (8 * sizeof (long int)) - 1)
46 return j0
< -1 ? 0 : sign
;
49 i0
+= 0x0000800000000000LL
>> j0
;
50 result
= i0
>> (48 - j0
);
52 if (sizeof (long int) == 4
54 && result
== LONG_MIN
)
55 /* Rounding brought the value out of range. */
56 feraiseexcept (FE_INVALID
);
61 result
= ((long int) i0
<< (j0
- 48)) | (i1
<< (j0
- 112));
64 uint64_t j
= i1
+ (0x8000000000000000ULL
>> (j0
- 48));
69 result
= (long int) i0
;
72 result
= ((long int) i0
<< (j0
- 48)) | (j
>> (112 - j0
));
74 if (sizeof (long int) == 8
76 && result
== LONG_MIN
)
77 /* Rounding brought the value out of range. */
78 feraiseexcept (FE_INVALID
);
85 /* The number is too large. Unless it rounds to LONG_MIN,
86 FE_INVALID must be raised and the return value is
89 if (FIX_LDBL_LONG_CONVERT_OVERFLOW
90 && !(sign
== -1 && x
> (_Float128
) LONG_MIN
- L(0.5)))
92 feraiseexcept (FE_INVALID
);
93 return sign
== 1 ? LONG_MAX
: LONG_MIN
;
95 else if (!FIX_LDBL_LONG_CONVERT_OVERFLOW
96 && x
<= (_Float128
) LONG_MIN
- L(0.5))
98 /* If truncation produces LONG_MIN, the cast will not raise
99 the exception, but may raise "inexact". */
100 feraiseexcept (FE_INVALID
);
104 /* The number is too large. It is left implementation defined
109 return sign
* result
;
112 libm_alias_ldouble (__lround
, lround
)