| David 'Digit' Turner | 122b335 | 2011-01-16 16:25:10 +0100 | [diff] [blame] | 1 | /* Copyright (C) 2011 The Android Open Source Project |
| 2 | ** |
| 3 | ** This software is licensed under the terms of the GNU General Public |
| 4 | ** License version 2, as published by the Free Software Foundation, and |
| 5 | ** may be copied, distributed, and modified under those terms. |
| 6 | ** |
| 7 | ** This program is distributed in the hope that it will be useful, |
| 8 | ** but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 9 | ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 10 | ** GNU General Public License for more details. |
| 11 | */ |
| 12 | #ifndef ANDROID_UTILS_DUFF_H |
| 13 | #define ANDROID_UTILS_DUFF_H |
| 14 | |
| 15 | /********************************************************************* |
| 16 | ********************************************************************* |
| 17 | ***** |
| 18 | ***** DUFF'S DEVICES |
| 19 | ***** |
| 20 | *****/ |
| 21 | |
| 22 | #define DUFF1(_count,_stmnt) \ |
| 23 | do { \ |
| 24 | int __n = (_count); \ |
| 25 | do { \ |
| 26 | _stmnt; \ |
| 27 | } while (--__n > 0); \ |
| 28 | } while (0); |
| 29 | |
| 30 | #define DUFF2(_count,_stmnt) \ |
| 31 | ({ \ |
| 32 | int __count = (_count); \ |
| 33 | int __n = (__count +1)/2; \ |
| 34 | switch (__count & 1) { \ |
| 35 | case 0: do { _stmnt; \ |
| 36 | case 1: _stmnt; \ |
| 37 | } while (--__n > 0); \ |
| 38 | } \ |
| 39 | }) |
| 40 | |
| 41 | #define DUFF4(_count,_stmnt) \ |
| 42 | ({ \ |
| 43 | int __count = (_count); \ |
| 44 | int __n = (__count +3)/4; \ |
| 45 | switch (__count & 3) { \ |
| 46 | case 0: do { _stmnt; \ |
| 47 | case 3: _stmnt; \ |
| 48 | case 2: _stmnt; \ |
| 49 | case 1: _stmnt; \ |
| 50 | } while (--__n > 0); \ |
| 51 | } \ |
| 52 | }) |
| 53 | |
| 54 | #define DUFF8(_count,_stmnt) \ |
| 55 | ({ \ |
| 56 | int __count = (_count); \ |
| 57 | int __n = (__count+7)/8; \ |
| 58 | switch (__count & 7) { \ |
| 59 | case 0: do { _stmnt; \ |
| 60 | case 7: _stmnt; \ |
| 61 | case 6: _stmnt; \ |
| 62 | case 5: _stmnt; \ |
| 63 | case 4: _stmnt; \ |
| 64 | case 3: _stmnt; \ |
| 65 | case 2: _stmnt; \ |
| 66 | case 1: _stmnt; \ |
| 67 | } while (--__n > 0); \ |
| 68 | } \ |
| 69 | }) |
| 70 | |
| 71 | #endif /* ANDROID_UTILS_DUFF_H */ |