1 files changed, 75 insertions, 0 deletions
diff --git a/src/VBox/Devices/BiosCommonCode/fmemcpy.asm b/src/VBox/Devices/BiosCommonCode/fmemcpy.asm
new file mode 100644
index 00000000..0c940652
--- /dev/null
+++ b/src/VBox/Devices/BiosCommonCode/fmemcpy.asm
@@ -0,0 +1,75 @@
+; $Id: fmemcpy.asm $
+;; @file
+; Compiler support routines.
+;
+
+;
+; Copyright (C) 2012-2022 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>.
+;
+; SPDX-License-Identifier: GPL-3.0-only
+;
+
+
+;*******************************************************************************
+;*  Exported Symbols                                                           *
+;*******************************************************************************
+public          _fmemcpy_
+
+
+                .8086
+
+_TEXT           segment public 'CODE' use16
+                assume cs:_TEXT
+
+
+;;
+; memcpy taking far pointers.
+;
+; cx, es may be modified; si, di are preserved
+;
+; @returns  dx:ax unchanged.
+; @param    dx:ax   Pointer to the destination memory.
+; @param    cx:bx   Pointer to the source memory.
+; @param    sp+2    The number of bytes to copy (dw).
+;
+_fmemcpy_:
+                push    bp
+                mov     bp, sp
+                push    di
+                push    ds
+                push    si
+
+                mov     es, dx
+                mov     di, ax
+                mov     ds, cx
+                mov     si, bx
+                mov     cx, [bp + 4]
+                rep     movsb
+
+                pop     si
+                pop     ds
+                pop     di
+                mov     sp, bp
+                pop     bp
+                ret
+
+
+_TEXT           ends
+                end
+