MdePkg/Library/BaseMemoryLibMmx/X64/CopyMem.S File Reference
Detailed Description
#
# ConvertAsm.py: Automatically generated from
CopyMem.asm
#
#------------------------------------------------------------------------------
#
# Copyright (c) 2006 - 2009, 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.S
#
# Abstract:
#
# CopyMem function
#
# Notes:
#
#------------------------------------------------------------------------------
#------------------------------------------------------------------------------
# VOID *
# EFIAPI
# InternalMemCopyMem (
# IN VOID *Destination,
# IN VOID *Source,
# IN UINTN Count
# )
#------------------------------------------------------------------------------
ASM_GLOBAL
ASM_PFX(InternalMemCopyMem)
ASM_PFX(InternalMemCopyMem):
pushq rsi
pushq rdi
movq rdx, rsi # rsi <- Source
movq rcx, rdi # rdi <- Destination
leaq -1(rsi, r8,), r9 # r9 <- End of Source
cmpq rdi, rsi
movq rdi, rax # rax <- Destination as return value
jae L0
cmpq rdi, r9
jae L_CopyBackward # Copy backward if overlapped
L0:
movq r8, rcx
andq $7, r8
shrq $3, rcx # rcx <- # of Qwords to copy
jz L_CopyBytes
movd mm0, r10 # (Save mm0 in r10)
L1:
movq (rsi), mm0
movntq mm0, (rdi)
addq $8, rsi
addq $8, rdi
loop L1
mfence
movd r10, mm0 # (Restore mm0)
jmp L_CopyBytes
L_CopyBackward:
movq r9, rsi # rsi <- End of Source
leaq -1(rdi, r8,), rdi # rdi <- End of Destination
std # set direction flag
L_CopyBytes:
movq r8, rcx
rep movsb # Copy bytes backward
cld
popq rdi
popq rsi
ret