audk/ArmPkg/Library/BaseMemoryLibStm/Arm/CopyMem.asm

115 lines
2.6 KiB
NASM
Executable File

;------------------------------------------------------------------------------
;
; CopyMem() worker for ARM
;
; This file started out as C code that did 64 bit moves if the buffer was
; 32-bit aligned, else it does a byte copy. It also does a byte copy for
; any trailing bytes. It was updated to do 32-byte copies using stm/ldm.
;
; Copyright (c) 2008 - 2010, Apple Inc. 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.
;
;------------------------------------------------------------------------------
/**
Copy Length bytes from Source to Destination. Overlap is OK.
This implementation
@param Destination Target of copy
@param Source Place to copy from
@param Length Number of bytes to copy
@return Destination
VOID *
EFIAPI
InternalMemCopyMem (
OUT VOID *DestinationBuffer,
IN CONST VOID *SourceBuffer,
IN UINTN Length
)
**/
\s\sEXPORT InternalMemCopyMem
\s\sAREA AsmMemStuff, CODE, READONLY
InternalMemCopyMem
\s\sstmfd\s\ssp!, {r4-r11, lr}
\s\stst\s\sr0, #3
\s\smov\s\sr11, r0
\s\smov\s\sr10, r0
\s\smov\s\sip, r2
\s\smov\s\slr, r1
\s\smovne\s\sr0, #0
\s\sbne\s\sL4
\s\stst\s\sr1, #3
\s\smovne\s\sr3, #0
\s\smoveq\s\sr3, #1
\s\scmp\s\sr2, #31
\s\smovls\s\sr0, #0
\s\sandhi\s\sr0, r3, #1
L4
\s\scmp\s\sr11, r1
\s\sbcc\s\sL26
\s\sbls\s\sL7
\s\srsb\s\sr3, r1, r11
\s\scmp\s\sip, r3
\s\sbcc\s\sL26
\s\scmp\s\sip, #0
\s\sbeq\s\sL7
\s\sadd\s\sr10, r11, ip
\s\sadd\s\slr, ip, r1
\s\sb\s\sL16
L29
\s\ssub\s\sip, ip, #8
\s\scmp\s\sip, #7
\s\sldrd\s\sr2, [lr, #-8]!
\s\smovls\s\sr0, #0
\s\scmp\s\sip, #0
\s\sstrd\s\sr2, [r10, #-8]!
\s\sbeq\s\sL7
L16
\s\scmp\s\sr0, #0
\s\sbne\s\sL29
\s\ssub\s\sr3, lr, #1
\s\ssub\s\sip, ip, #1
\s\sldrb\s\sr3, [r3, #0]\s\s
\s\ssub\s\sr2, r10, #1
\s\scmp\s\sip, #0
\s\ssub\s\sr10, r10, #1
\s\ssub\s\slr, lr, #1
\s\sstrb\s\sr3, [r2, #0]
\s\sbne\s\sL16
\s\sb L7
L11
\s\sldrb\s\sr3, [lr], #1\s\s
\s\ssub\s\sip, ip, #1
\s\sstrb\s\sr3, [r10], #1
L26
\s\scmp\s\sip, #0
\s\sbeq\s\sL7
L30
\s\scmp\s\sr0, #0
\s\sbeq\s\sL11
\s\ssub\s\sip, ip, #32
\s\scmp\s\sip, #31
\s\sldmia\s\slr!, {r2-r9}
\s\smovls\s\sr0, #0
\s\scmp\s\sip, #0
\s\sstmia\s\sr10!, {r2-r9}
\s\sbne\s\sL30
L7
mov\s\sr0, r11
\s\sldmfd\s\ssp!, {r4-r11, pc}
\s\s
END