1 files changed, 110 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/string/mempcpy.asm b/src/VBox/Runtime/common/string/mempcpy.asm
new file mode 100644
index 00000000..a6428391
--- /dev/null
+++ b/src/VBox/Runtime/common/string/mempcpy.asm
@@ -0,0 +1,110 @@
+; $Id: mempcpy.asm $
+;; @file
+; IPRT - No-CRT mempcpy - 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: rcx  x86:[esp+4]    wcall: eax
+; @param    pvSrc   gcc: rsi  msc: rdx  x86:[esp+8]    wcall: edx
+; @param    cb      gcc: rdx  msc: r8   x86:[esp+0ch]  wcall: ebx
+RT_NOCRT_BEGINPROC mempcpy
+        cld                             ; paranoia
+
+        ; Do the bulk of the work.
+%ifdef RT_ARCH_AMD64
+ %ifdef ASM_CALL64_MSC
+        mov     r10, rdi                ; save
+        mov     r11, rsi                ; save
+        mov     rdi, rcx
+        mov     rsi, rdx
+        mov     rcx, r8
+        mov     rdx, r8
+ %else
+        mov     rcx, rdx
+ %endif
+        shr     rcx, 3
+        rep movsq
+%else
+ %ifdef ASM_CALL32_WATCOM
+        xchg    eax, edi                ; saving edi in eax and loading it
+        push    esi
+        mov     esi, edx
+        mov     ecx, ebx
+        mov     edx, ebx
+ %else
+        mov     eax, edi                ; saving edi in eax
+        push    esi
+        mov     ecx, [esp + 0ch + 4]
+        mov     edi, [esp + 04h + 4]
+        mov     esi, [esp + 08h + 4]
+        mov     edx, ecx
+ %endif
+        shr     ecx, 2
+        rep movsd
+%endif
+
+        ; The remaining bytes.
+%ifdef RT_ARCH_AMD64
+        test    dl, 4
+        jz      .dont_move_dword
+        movsd
+%endif
+.dont_move_dword:
+        test    dl, 2
+        jz      .dont_move_word
+        movsw
+.dont_move_word:
+        test    dl, 1
+        jz      .dont_move_byte
+        movsb
+.dont_move_byte:
+
+        ; restore & return
+%ifdef RT_ARCH_AMD64
+        mov     rax, rdi
+ %ifdef ASM_CALL64_MSC
+        mov     rsi, r11
+        mov     rdi, r10
+ %endif
+%else
+        pop     esi
+        xchg    eax, edi
+%endif
+        ret
+ENDPROC RT_NOCRT(mempcpy)
+