/* * Copyright (C) 2013 ARM Ltd. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <linux/linkage.h> #include <asm/assembler.h> /* * Move a buffer from src to test (alignment handled by the hardware). * If dest <= src, call memcpy, otherwise copy in reverse order. * * Parameters: * x0 - dest * x1 - src * x2 - n * Returns: * x0 - dest */ ENTRY(memmove) cmp x0, x1 b.ls memcpy add x4, x0, x2 add x1, x1, x2 subs x2, x2, #8 b.mi 2f 1: ldr x3, [x1, #-8]! subs x2, x2, #8 str x3, [x4, #-8]! b.pl 1b 2: adds x2, x2, #4 b.mi 3f ldr w3, [x1, #-4]! sub x2, x2, #4 str w3, [x4, #-4]! 3: adds x2, x2, #2 b.mi 4f ldrh w3, [x1, #-2]! sub x2, x2, #2 strh w3, [x4, #-2]! 4: adds x2, x2, #1 b.mi 5f ldrb w3, [x1, #-1] strb w3, [x4, #-1] 5: ret ENDPROC(memmove)