CloverBootloader/MdePkg/Library/BaseMemoryLibOptPei/Ia32/CompareMem.nasm

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;------------------------------------------------------------------------------
;
; Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
; Module Name:
;
; CompareMem.Asm
;
; Abstract:
;
; CompareMem function
;
; Notes:
;
; The following BaseMemoryLib instances contain the same copy of this file:
;
; BaseMemoryLibRepStr
; BaseMemoryLibMmx
; BaseMemoryLibSse2
; BaseMemoryLibOptDxe
; BaseMemoryLibOptPei
;
;------------------------------------------------------------------------------
SECTION .text
;------------------------------------------------------------------------------
; INTN
; EFIAPI
; InternalMemCompareMem (
; IN CONST VOID *DestinationBuffer,
; IN CONST VOID *SourceBuffer,
; IN UINTN Length
; );
;------------------------------------------------------------------------------
global ASM_PFX(InternalMemCompareMem)
ASM_PFX(InternalMemCompareMem):
push esi
push edi
mov esi, [esp + 12]
mov edi, [esp + 16]
mov ecx, [esp + 20]
repe cmpsb
movzx eax, byte [esi - 1]
movzx edx, byte [edi - 1]
sub eax, edx
pop edi
pop esi
ret