#------------------------------------------------------------------------------

#

# 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 # Overlapped?

jae L_CopyBackward # Copy backward if overlapped

L0:

xorl %ecx, %ecx

subl %edi, %ecx

andl $15, %ecx # ecx + edi aligns on 16-byte boundary

jz L1

cmpl %edx, %ecx

cmova %edx, %ecx

subl %ecx, %edx # edx <- remaining bytes to copy

rep

movsb

L1:

movl %edx, %ecx

andl $15, %edx

shrl $4, %ecx # ecx <- # of DQwords to copy

jz L_CopyBytes

addl $-16, %esp

movdqu %xmm0, (%esp)

L2:

movdqu (%esi), %xmm0

movntdq %xmm0, (%edi)

addl $16, %esi

addl $16, %edi

loop L2

mfence

movdqu (%esp),%xmm0

addl $16, %esp # stack cleanup

jmp L_CopyBytes

L_CopyBackward:

movl %eax, %esi # esi <- Last byte in Source

leal -1(%edi,%edx,), %edi # edi <- Last byte in Destination

std

L_CopyBytes:

movl %edx, %ecx

rep

movsb

cld

movl 12(%esp), %eax # eax <- Destination as return value

pop %edi

pop %esi

ret