diff options
Diffstat (limited to 'src/VBox/Runtime/common/string/memset.asm')
| -rw-r--r-- | src/VBox/Runtime/common/string/memset.asm | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/string/memset.asm b/src/VBox/Runtime/common/string/memset.asm new file mode 100644 index 00000000..a2523c84 --- /dev/null +++ b/src/VBox/Runtime/common/string/memset.asm @@ -0,0 +1,141 @@ +; $Id: memset.asm $ +;; @file +; IPRT - No-CRT memset - AMD64 & X86. +; + +; +; Copyright (C) 2006-2023 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 "iprt/asmdefs.mac" + +BEGINCODE + +;; +; @param pvDst gcc: rdi msc: ecx x86:[esp+4] wcall: eax +; @param ch gcc: esi msc: edx x86:[esp+8] wcall: edx +; @param cb gcc: rdx msc: r8 x86:[esp+0ch] wcall: ebx +RT_NOCRT_BEGINPROC memset + cld +%ifdef RT_ARCH_AMD64 + %ifdef ASM_CALL64_MSC + mov r9, rdi ; save rdi in r9 + mov rdi, rcx + mov r10, rcx ; the return value. + movzx eax, dl + cmp r8, 32 + jb .dobytes + + ; eax = (al << 24) | (al << 16) | (al << 8) | al; + ; rdx = (eax << 32) | eax + movzx edx, dl + mov rax, qword 0101010101010101h + imul rax, rdx + + ; todo: alignment. + mov rcx, r8 + shr rcx, 3 + rep stosq + + and r8, 7 +.dobytes: + mov rcx, r8 + rep stosb + + mov rdi, r9 ; restore rdi + mov rax, r10 + + %else ; GCC + mov r10, rdi ; the return value. + movzx eax, sil + cmp rdx, 32 + jb .dobytes + + ; eax = (al << 24) | (al << 16) | (al << 8) | al; + ; rdx = (eax << 32) | eax + movzx esi, sil + mov rax, qword 0101010101010101h + imul rax, rsi + + ; todo: alignment. + mov rcx, rdx + shr rcx, 3 + rep stosq + + and rdx, 7 +.dobytes: + mov rcx, rdx + rep stosb + + mov rax, r10 + %endif ; GCC + +%else ; X86 + push edi + + %ifdef ASM_CALL32_WATCOM + push eax + mov edi, eax + mov ecx, ebx + movzx eax, dl + %else + mov ecx, [esp + 0ch + 4] + movzx eax, byte [esp + 08h + 4] + mov edi, [esp + 04h + 4] + %endif + cmp ecx, 12 + jb .dobytes + + ; eax = (al << 24) | (al << 16) | (al << 8) | al; + mov ah, al + mov edx, eax + shl edx, 16 + or eax, edx + + mov edx, ecx + shr ecx, 2 + rep stosd + + and edx, 3 + mov ecx, edx +.dobytes: + rep stosb + + %ifdef ASM_CALL32_WATCOM + pop eax + pop edi + %else + pop edi + mov eax, [esp + 4] + %endif +%endif ; X86 + ret +ENDPROC RT_NOCRT(memset) + |