blob: f273586fe87f1ca788a0b382261b81f8b673053b [file] [log] [blame]
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2009 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/symbol.h>
#include <grub/i386/memory.h>
.p2align 2
VARIABLE(grub_relocator_backward_start)
/* mov imm32, %eax */
.byte 0xb8
VARIABLE(grub_relocator_backward_dest)
.long 0
movl %eax, %edi
/* mov imm32, %eax */
.byte 0xb8
VARIABLE(grub_relocator_backward_src)
.long 0
movl %eax, %esi
/* mov imm32, %ecx */
.byte 0xb9
VARIABLE(grub_relocator_backward_chunk_size)
.long 0
add %ecx, %esi
add %ecx, %edi
/* Backward movsb is implicitly off-by-one. compensate that. */
sub $1, %esi
sub $1, %edi
/* Backward copy. */
std
rep
movsb
VARIABLE(grub_relocator_backward_end)
VARIABLE(grub_relocator_forward_start)
/* mov imm32, %eax */
.byte 0xb8
VARIABLE(grub_relocator_forward_dest)
.long 0
movl %eax, %edi
/* mov imm32, %rax */
.byte 0xb8
VARIABLE(grub_relocator_forward_src)
.long 0
movl %eax, %esi
/* mov imm32, %ecx */
.byte 0xb9
VARIABLE(grub_relocator_forward_chunk_size)
.long 0
/* Forward copy. */
cld
rep
movsb
VARIABLE(grub_relocator_forward_end)