Catalin Marinas | 4a89922 | 2013-03-21 16:16:43 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2013 ARM Ltd. |
| 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 version 2 as |
| 6 | * published by the Free Software Foundation. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 11 | * GNU General Public License for more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public License |
| 14 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 15 | */ |
| 16 | |
| 17 | #include <linux/linkage.h> |
| 18 | #include <asm/assembler.h> |
| 19 | |
| 20 | /* |
| 21 | * Move a buffer from src to test (alignment handled by the hardware). |
| 22 | * If dest <= src, call memcpy, otherwise copy in reverse order. |
| 23 | * |
| 24 | * Parameters: |
| 25 | * x0 - dest |
| 26 | * x1 - src |
| 27 | * x2 - n |
| 28 | * Returns: |
| 29 | * x0 - dest |
| 30 | */ |
| 31 | ENTRY(memmove) |
| 32 | cmp x0, x1 |
| 33 | b.ls memcpy |
| 34 | add x4, x0, x2 |
| 35 | add x1, x1, x2 |
| 36 | subs x2, x2, #8 |
| 37 | b.mi 2f |
| 38 | 1: ldr x3, [x1, #-8]! |
| 39 | subs x2, x2, #8 |
| 40 | str x3, [x4, #-8]! |
| 41 | b.pl 1b |
| 42 | 2: adds x2, x2, #4 |
| 43 | b.mi 3f |
| 44 | ldr w3, [x1, #-4]! |
| 45 | sub x2, x2, #4 |
| 46 | str w3, [x4, #-4]! |
| 47 | 3: adds x2, x2, #2 |
| 48 | b.mi 4f |
| 49 | ldrh w3, [x1, #-2]! |
| 50 | sub x2, x2, #2 |
| 51 | strh w3, [x4, #-2]! |
| 52 | 4: adds x2, x2, #1 |
| 53 | b.mi 5f |
| 54 | ldrb w3, [x1, #-1] |
| 55 | strb w3, [x4, #-1] |
| 56 | 5: ret |
| 57 | ENDPROC(memmove) |