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#------------------------------------------------------------------------------
#
# Copyright (c) 2006, Intel Corporation
# All rights reserved. This program and the accompanying materials
# are licensed and made available under the terms and conditions of the BSD License
# which accompanies this distribution. The full text of the license may be found at
# http://opensource.org/licenses/bsd-license.php
#
# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#
# Module Name:
#
# CopyMem.Asm
#
# Abstract:
#
# CopyMem function
#
# Notes:
#
#------------------------------------------------------------------------------
.globl _InternalMemCopyMem
#------------------------------------------------------------------------------
# VOID *
# EFIAPI
# InternalMemCopyMem (
# IN VOID *Destination,
# IN VOID *Source,
# IN UINTN Count
# );
#------------------------------------------------------------------------------
_InternalMemCopyMem:
push %esi
push %edi
movl 16(%esp), %esi # esi <- Source
movl 12(%esp), %edi # edi <- Destination
movl 20(%esp), %edx # edx <- Count
cmpl %esi, %edi
je L_CopyDone
cmpl $0, %edx
je L_CopyDone
leal -1(%esi, %edx), %eax # eax <- End of Source
cmpl %esi, %edi
jae L_CopyBytes
cmpl %eax, %edi
jb L_CopyBytes # Copy backward if overlapped
movl %esi, %eax # esi <- End of Source
leal -1(%edi, %edx), %edi # edi <- End of Destination
std
L_CopyBytes:
movl %ecx, %edx
rep
movsb # Copy bytes backward
cld
L_CopyDone:
movl 12(%esp), %eax # eax <- Destination as return value
pop %edi
pop %esi
ret
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