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[mirror_edk2.git] / MdePkg / Library / BaseMemoryLibMmx / X64 / ZeroMem.S

#
# ConvertAsm.py: Automatically generated from ZeroMem.asm
#
#------------------------------------------------------------------------------
#
# 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:
#
#   ZeroMem.S
#
# Abstract:
#
#   ZeroMem function
#
# Notes:
#
#------------------------------------------------------------------------------


#------------------------------------------------------------------------------
#  VOID *
#  InternalMemZeroMem (
#    IN VOID   *Buffer,
#    IN UINTN  Count
#    );
#------------------------------------------------------------------------------
.intel_syntax noprefix
.globl ASM_PFX(InternalMemZeroMem)
ASM_PFX(InternalMemZeroMem):
    push    rdi
    mov     rdi, rcx
    mov     rcx, rdx
    mov     r8, rdi
    and     edx, 7
    shr     rcx, 3
    jz      L_ZeroBytes
    pxor    mm0, mm0
L0:
    movntq  [rdi], mm0
    add     rdi, 8
    loop    L0
    mfence
L_ZeroBytes:
    xor     eax, eax
    mov     ecx, edx
    rep     stosb
    mov     rax, r8
    pop     rdi
    ret