# | |
# 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 |