projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| b75bc69c JM |
1 | /* Round double value to long int. |
| 2 | Copyright (C) 1997-2015 Free Software Foundation, Inc. | |
| 3 | This file is part of the GNU C Library. | |
| 4 | ||
| 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. | |
| 9 | ||
| 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. | |
| 14 | ||
| 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 | <http://www.gnu.org/licenses/>. */ | |
| 18 | ||
| 19 | #include <math.h> | |
| 20 | ||
| 21 | #include <math_private.h> | |
| 22 | ||
| 23 | /* For LP64, lround is an alias for llround. */ | |
| 24 | #ifndef _LP64 | |
| 25 | ||
| 26 | long int | |
| 27 | __lround (double x) | |
| 28 | { | |
| 29 | int32_t j0; | |
| 30 | int64_t i0; | |
| 31 | long int result; | |
| 32 | int sign; | |
| 33 | ||
| 34 | EXTRACT_WORDS64 (i0, x); | |
| 35 | j0 = ((i0 >> 52) & 0x7ff) - 0x3ff; | |
| 36 | sign = i0 < 0 ? -1 : 1; | |
| 37 | i0 &= UINT64_C(0xfffffffffffff); | |
| 38 | i0 |= UINT64_C(0x10000000000000); | |
| 39 | ||
| 40 | if (j0 < (int32_t) (8 * sizeof (long int)) - 1) | |
| 41 | { | |
| 42 | if (j0 < 0) | |
| 43 | return j0 < -1 ? 0 : sign; | |
| 44 | else if (j0 >= 52) | |
| 45 | result = i0 << (j0 - 52); | |
| 46 | else | |
| 47 | { | |
| 48 | i0 += UINT64_C(0x8000000000000) >> j0; | |
| 49 | ||
| 50 | result = i0 >> (52 - j0); | |
| 51 | } | |
| 52 | } | |
| 53 | else | |
| 54 | { | |
| 55 | /* The number is too large. It is left implementation defined | |
| 56 | what happens. */ | |
| 57 | return (long int) x; | |
| 58 | } | |
| 59 | ||
| 60 | return sign * result; | |
| 61 | } | |
| 62 | ||
| 63 | weak_alias (__lround, lround) | |
| 64 | # ifdef NO_LONG_DOUBLE | |
| 65 | strong_alias (__lround, __lroundl) | |
| 66 | weak_alias (__lround, lroundl) | |
| 67 | # endif | |
| 68 | ||
| 69 | #endif |