summaryrefslogtreecommitdiff
path: root/src/VBox/Devices/BiosCommonCode/__U8LS.asm
blob: 3c21ebd3e08573ae9c69b21fa82ebb1a97aa0a50 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
; $Id$
;; @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          __U8LS


                .8086

_TEXT           segment public 'CODE' use16
                assume cs:_TEXT

;;
; 64-bit left shift.
;
; @param    ax:bx:cx:dx Value. (AX is the most significant, DX the least)
; @param    si          Shift count.
; @returns  ax:bx:cx:dx Shifted value.
; si is zeroed
;
__U8LS:

                test    si, si
                jz      u8ls_quit
u8ls_rot:
                shl     dx, 1
                rcl     cx, 1
                rcl     bx, 1
                rcl     ax, 1
                dec     si
                jnz     u8ls_rot
u8ls_quit:
                ret


_TEXT           ends
                end