audk/MdePkg/Library/BaseMemoryLibOptDxe/X64/CompareMem.asm

55 lines
1.6 KiB
NASM

;------------------------------------------------------------------------------
;
; Copyright (c) 2006, 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:
;
; CompareMem.Asm
;
; Abstract:
;
; CompareMem function
;
; Notes:
;
; The following BaseMemoryLib instances contain the same copy of this file:
;
; BaseMemoryLibRepStr
; BaseMemoryLibMmx
; BaseMemoryLibSse2
; BaseMemoryLibOptDxe
; BaseMemoryLibOptPei
;
;------------------------------------------------------------------------------
.code
;------------------------------------------------------------------------------
; INTN
; EFIAPI
; InternalMemCompareMem (
; IN CONST VOID *DestinationBuffer,
; IN CONST VOID *SourceBuffer,
; IN UINTN Length
; );
;------------------------------------------------------------------------------
InternalMemCompareMem PROC USES rsi rdi
mov rsi, rcx
mov rdi, rdx
mov rcx, r8
repe cmpsb
movzx rax, byte ptr [rsi - 1]
movzx rdx, byte ptr [rdi - 1]
sub rax, rdx
ret
InternalMemCompareMem ENDP
END