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#------------------------------------------------------------------------------
#
# Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
# 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:
#
#------------------------------------------------------------------------------
ASM_GLOBAL ASM_PFX(InternalMemCopyMem)
#------------------------------------------------------------------------------
# VOID *
# EFIAPI
# InternalMemCopyMem (
# IN VOID *Destination,
# IN VOID *Source,
# IN UINTN Count
# );
#------------------------------------------------------------------------------
ASM_PFX(InternalMemCopyMem):
push %esi
push %edi
movl 16(%esp), %esi # esi <- Source
movl 12(%esp), %edi # edi <- Destination
movl 20(%esp), %edx # edx <- Count
leal -1(%esi, %edx), %eax # eax <- End of Source
cmpl %edi, %esi
jae L0
cmpl %edi, %eax
jae L_CopyBackward # Copy backward if overlapped
L0:
movl %edx, %ecx
andl $3, %edx
shrl $2, %ecx
rep
movsl # Copy as many Dwords as possible
jmp L_CopyBytes
L_CopyBackward:
movl %eax, %esi # esi <- End of Source
leal -1(%edi, %edx), %edi # edi <- End of Destination
std
L_CopyBytes:
movl %edx, %ecx
rep
movsb # Copy bytes backward
cld
movl 12(%esp), %eax # eax <- Destination as return value
pop %edi
pop %esi
ret
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