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; $Id: bs3-cmn-MemZero.asm $
;; @file
; BS3Kit - Bs3MemZero.
;
;
; Copyright (C) 2007-2023 Oracle and/or its affiliates.
;
; This file is part of VirtualBox base platform packages, as
; available from https://www.virtualbox.org.
;
; This program is free software; you can redistribute it and/or
; modify it under the terms of the GNU General Public License
; as published by the Free Software Foundation, in version 3 of the
; License.
;
; This program is distributed in the hope that it will be useful, but
; WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
; General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with this program; if not, see <https://www.gnu.org/licenses>.
;
; The contents of this file may alternatively be used under the terms
; of the Common Development and Distribution License Version 1.0
; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
; in the VirtualBox distribution, in which case the provisions of the
; CDDL are applicable instead of those of the GPL.
;
; You may elect to license modified versions of this file under the
; terms and conditions of either the GPL or the CDDL or both.
;
; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
;
%include "bs3kit-template-header.mac"
;;
; @cproto BS3_DECL(void) Bs3MemZero_c16(void BS3_FAR *pvDst, size_t cbDst);
;
BS3_PROC_BEGIN_CMN Bs3MemZero, BS3_PBC_HYBRID
%ifdef RT_ARCH_AMD64
push rdi
mov rdi, rcx ; rdi = pvDst
mov rcx, rdx ; rcx = cbDst
shr rcx, 3 ; calc qword count.
xor eax, eax ; rax = 0 (filler qword)
cld
rep stosq
mov rcx, rdx ; cbDst
and rcx, 7 ; calc trailing byte count.
rep stosb
pop rdi
BS3_HYBRID_RET
%elif ARCH_BITS == 16
push bp
mov bp, sp
push di
push es
mov di, [bp + 2 + cbCurRetAddr] ; pvDst.off
mov dx, [bp + 2 + cbCurRetAddr + 2] ; pvDst.sel
mov es, dx
mov cx, [bp + 2 + cbCurRetAddr + 4] ; cbDst
shr cx, 1 ; calc dword count.
xor ax, ax
rep stosw
mov cx, [bp + 2 + cbCurRetAddr + 4] ; cbDst
and cx, 1 ; calc tailing byte count.
rep stosb
pop es
pop di
pop bp
BS3_HYBRID_RET
%elif ARCH_BITS == 32
push edi
mov edi, [esp + 8] ; pvDst
mov ecx, [esp + 8 + 4] ; cbDst
shr cx, 2 ; calc dword count.
xor eax, eax
rep stosd
mov ecx, [esp + 8 + 4] ; cbDst
and ecx, 3 ; calc tailing byte count.
rep stosb
pop edi
BS3_HYBRID_RET
%else
%error "Unknown bitness."
%endif
BS3_PROC_END_CMN Bs3MemZero
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