audk/MdePkg/Library/BaseMemoryLibOptDxe/X64/CopyMem.S

84 lines
2.8 KiB
ArmAsm

#
# ConvertAsm.py: Automatically generated from CopyMem.asm
#
#------------------------------------------------------------------------------
#
# 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.S
#
# Abstract:
#
# CopyMem function
#
# Notes:
#
#------------------------------------------------------------------------------
#------------------------------------------------------------------------------
# VOID *
# EFIAPI
# InternalMemCopyMem (
# IN VOID *Destination,
# IN VOID *Source,
# IN UINTN Count
# )
#------------------------------------------------------------------------------
.intel_syntax noprefix
ASM_GLOBAL ASM_PFX(InternalMemCopyMem)
ASM_PFX(InternalMemCopyMem):
push rsi
push rdi
mov rsi, rdx # rsi <- Source
mov rdi, rcx # rdi <- Destination
lea r9, [rsi + r8 - 1] # r9 <- Last byte of Source
cmp rsi, rdi
mov rax, rdi # rax <- Destination as return value
jae L0 # Copy forward if Source > Destination
cmp r9, rdi # Overlapped?
jae L_CopyBackward # Copy backward if overlapped
L0:
xor rcx, rcx
sub rcx, rdi # rcx <- -rdi
and rcx, 15 # rcx + rsi should be 16 bytes aligned
jz L1 # skip if rcx == 0
cmp rcx, r8
cmova rcx, r8
sub r8, rcx
rep movsb
L1:
mov rcx, r8
and r8, 15
shr rcx, 4 # rcx <- # of DQwords to copy
jz L_CopyBytes
movdqa [rsp + 0x18], xmm0 # save xmm0 on stack
L2:
movdqu xmm0, [rsi] # rsi may not be 16-byte aligned
movntdq [rdi], xmm0 # rdi should be 16-byte aligned
add rsi, 16
add rdi, 16
loop L2
mfence
movdqa xmm0, [rsp + 0x18] # restore xmm0
jmp L_CopyBytes # copy remaining bytes
L_CopyBackward:
mov rsi, r9 # rsi <- Last byte of Source
lea rdi, [rdi + r8 - 1] # rdi <- Last byte of Destination
std
L_CopyBytes:
mov rcx, r8
rep movsb
cld
pop rdi
pop rsi
ret