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;------------------------------------------------------------------------------
;
; Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
; Module Name:
;
;   ScanMem8.Asm
;
; Abstract:
;
;   ScanMem8 function
;
; Notes:
;
;   The following BaseMemoryLib instances contain the same copy of this file:
;
;       BaseMemoryLibRepStr
;       BaseMemoryLibMmx
;       BaseMemoryLibSse2
;       BaseMemoryLibOptDxe
;       BaseMemoryLibOptPei
;
;------------------------------------------------------------------------------

    DEFAULT REL
    SECTION .text

;------------------------------------------------------------------------------
; CONST VOID *
; EFIAPI
; InternalMemScanMem8 (
;   IN      CONST VOID                *Buffer,
;   IN      UINTN                     Length,
;   IN      UINT8                     Value
;   );
;------------------------------------------------------------------------------
global ASM_PFX(InternalMemScanMem8)
ASM_PFX(InternalMemScanMem8):
    push    rdi
    mov     rdi, rcx
    mov     rcx, rdx
    mov     rax, r8
    repne   scasb
    lea     rax, [rdi - 1]
    cmovnz  rax, rcx                    ; set rax to 0 if not found
    pop     rdi
    ret