projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| eb0f39b6 L |
1 | /* Round double value to long long int. |
| 2 | Copyright (C) 1997-2012 Free Software Foundation, Inc. | |
| 3 | This file is part of the GNU C Library. | |
| 4 | Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. | |
| 5 | ||
| 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. | |
| 10 | ||
| 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. | |
| 15 | ||
| 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 | <http://www.gnu.org/licenses/>. */ | |
| 19 | ||
| 20 | #define lround __hidden_lround | |
| 21 | #define __lround __hidden___lround | |
| 22 | ||
| 23 | #include <math.h> | |
| 24 | ||
| 25 | #include <math_private.h> | |
| 26 | ||
| 27 | ||
| 28 | long long int | |
| 29 | __llround (double x) | |
| 30 | { | |
| 31 | int32_t j0; | |
| 32 | int64_t i0; | |
| 33 | long long int result; | |
| 34 | int sign; | |
| 35 | ||
| 36 | EXTRACT_WORDS64 (i0, x); | |
| 37 | j0 = ((i0 >> 52) & 0x7ff) - 0x3ff; | |
| 38 | sign = i0 < 0 ? -1 : 1; | |
| 39 | i0 &= UINT64_C(0xfffffffffffff); | |
| 40 | i0 |= UINT64_C(0x10000000000000); | |
| 41 | ||
| 42 | if (j0 < (int32_t) (8 * sizeof (long long int)) - 1) | |
| 43 | { | |
| 44 | if (j0 < 0) | |
| 45 | return j0 < -1 ? 0 : sign; | |
| 46 | else if (j0 >= 52) | |
| 47 | result = i0 << (j0 - 52); | |
| 48 | else | |
| 49 | { | |
| 50 | i0 += UINT64_C(0x8000000000000) >> j0; | |
| 51 | ||
| 52 | result = i0 >> (52 - j0); | |
| 53 | } | |
| 54 | } | |
| 55 | else | |
| 56 | { | |
| 57 | /* The number is too large. It is left implementation defined | |
| 58 | what happens. */ | |
| 59 | return (long long int) x; | |
| 60 | } | |
| 61 | ||
| 62 | return sign * result; | |
| 63 | } | |
| 64 | ||
| 65 | weak_alias (__llround, llround) | |
| 66 | #ifdef NO_LONG_DOUBLE | |
| 67 | strong_alias (__llround, __lroundl) | |
| 68 | weak_alias (__llround, lroundl) | |
| 69 | #endif | |
| 70 | ||
| 71 | /* long has the same width as long long on 64-bit machines. */ | |
| 72 | #undef lround | |
| 73 | #undef __lround | |
| 74 | strong_alias (__llround, __lround) | |
| 75 | weak_alias (__llround, lround) | |
| 76 | #ifdef NO_LONG_DOUBLE | |
| 77 | strong_alias (__llround, __llroundl) | |
| 78 | weak_alias (__llround, llroundl) | |
| 79 | #endif |