projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| dfd2257a | 1 | /* Round long double value to long int. |
| b168057a | 2 | Copyright (C) 1997-2015 Free Software Foundation, Inc. |
| dfd2257a | 3 | This file is part of the GNU C Library. |
| abfbdde1 | 4 | Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and |
| 350635a5 | 5 | Jakub Jelinek <jj@ultra.linux.cz>, 1999. |
| dfd2257a UD |
6 | |
| 7 | The GNU C Library is free software; you can redistribute it and/or | |
| 41bdb6e2 AJ |
8 | modify it under the terms of the GNU Lesser General Public |
| 9 | License as published by the Free Software Foundation; either | |
| 10 | version 2.1 of the License, or (at your option) any later version. | |
| dfd2257a UD |
11 | |
| 12 | The GNU C Library is distributed in the hope that it will be useful, | |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 41bdb6e2 | 15 | Lesser General Public License for more details. |
| dfd2257a | 16 | |
| 41bdb6e2 | 17 | You should have received a copy of the GNU Lesser General Public |
| 59ba27a6 PE |
18 | License along with the GNU C Library; if not, see |
| 19 | <http://www.gnu.org/licenses/>. */ | |
| dfd2257a UD |
20 | |
| 21 | #include <math.h> | |
| 22 | ||
| 1ed0291c | 23 | #include <math_private.h> |
| dfd2257a UD |
24 | |
| 25 | ||
| 26 | long int | |
| 27 | __lroundl (long double x) | |
| 28 | { | |
| abfbdde1 UD |
29 | int64_t j0; |
| 30 | u_int64_t i1, i0; | |
| dfd2257a UD |
31 | long int result; |
| 32 | int sign; | |
| 33 | ||
| abfbdde1 UD |
34 | GET_LDOUBLE_WORDS64 (i0, i1, x); |
| 35 | j0 = ((i0 >> 48) & 0x7fff) - 0x3fff; | |
| 36 | sign = (i0 & 0x8000000000000000ULL) != 0 ? -1 : 1; | |
| 37 | i0 &= 0x0000ffffffffffffLL; | |
| 38 | i0 |= 0x0001000000000000LL; | |
| dfd2257a | 39 | |
| abfbdde1 | 40 | if (j0 < 48) |
| dfd2257a UD |
41 | { |
| 42 | if (j0 < 0) | |
| 43 | return j0 < -1 ? 0 : sign; | |
| 44 | else | |
| 45 | { | |
| abfbdde1 UD |
46 | i0 += 0x0000800000000000LL >> j0; |
| 47 | result = i0 >> (48 - j0); | |
| dfd2257a UD |
48 | } |
| 49 | } | |
| cc3fa755 | 50 | else if (j0 < (int32_t) (8 * sizeof (long int)) - 1) |
| dfd2257a | 51 | { |
| abfbdde1 UD |
52 | if (j0 >= 112) |
| 53 | result = ((long int) i0 << (j0 - 48)) | (i1 << (j0 - 112)); | |
| dfd2257a UD |
54 | else |
| 55 | { | |
| abfbdde1 | 56 | u_int64_t j = i1 + (0x8000000000000000ULL >> (j0 - 48)); |
| dfd2257a UD |
57 | if (j < i1) |
| 58 | ++i0; | |
| 59 | ||
| 39007ae3 UD |
60 | if (j0 == 48) |
| 61 | result = (long int) i0; | |
| 62 | else | |
| 63 | result = ((long int) i0 << (j0 - 48)) | (j >> (112 - j0)); | |
| dfd2257a UD |
64 | } |
| 65 | } | |
| 66 | else | |
| 67 | { | |
| 68 | /* The number is too large. It is left implementation defined | |
| 69 | what happens. */ | |
| 70 | return (long int) x; | |
| 71 | } | |
| 72 | ||
| 73 | return sign * result; | |
| 74 | } | |
| 75 | ||
| 76 | weak_alias (__lroundl, lroundl) |