Palmer Dabbelt | b35cd98 | 2017-05-23 10:28:26 -0700 | [diff] [blame] | 1 | /* |
| 2 | * lib/lshrdi3.c |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; either version 2 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program; if not, see the file COPYING, or write |
| 16 | * to the Free Software Foundation, Inc. |
| 17 | */ |
| 18 | |
| 19 | #include <linux/module.h> |
Christoph Hellwig | 4db2b60 | 2017-11-22 11:47:28 +0100 | [diff] [blame^] | 20 | #include <linux/libgcc.h> |
Palmer Dabbelt | b35cd98 | 2017-05-23 10:28:26 -0700 | [diff] [blame] | 21 | |
| 22 | long long notrace __lshrdi3(long long u, word_type b) |
| 23 | { |
| 24 | DWunion uu, w; |
| 25 | word_type bm; |
| 26 | |
| 27 | if (b == 0) |
| 28 | return u; |
| 29 | |
| 30 | uu.ll = u; |
| 31 | bm = 32 - b; |
| 32 | |
| 33 | if (bm <= 0) { |
| 34 | w.s.high = 0; |
| 35 | w.s.low = (unsigned int) uu.s.high >> -bm; |
| 36 | } else { |
| 37 | const unsigned int carries = (unsigned int) uu.s.high << bm; |
| 38 | |
| 39 | w.s.high = (unsigned int) uu.s.high >> b; |
| 40 | w.s.low = ((unsigned int) uu.s.low >> b) | carries; |
| 41 | } |
| 42 | |
| 43 | return w.ll; |
| 44 | } |
| 45 | EXPORT_SYMBOL(__lshrdi3); |