#------------------------------------------------------------------------------ | |
# | |
# Copyright (c) 2006 - 2008, 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: | |
# | |
#------------------------------------------------------------------------------ | |
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 |