| 1 | ; $Id: bs3-wc16-I4D.asm 106061 2024-09-16 14:03:52Z vboxsync $
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| 2 | ;; @file
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| 3 | ; BS3Kit - 16-bit Watcom C/C++, 32-bit signed integer division.
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| 4 | ;
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| 5 |
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| 6 | ;
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| 7 | ; Copyright (C) 2007-2024 Oracle and/or its affiliates.
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| 8 | ;
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| 9 | ; This file is part of VirtualBox base platform packages, as
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| 10 | ; available from https://www.virtualbox.org.
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| 11 | ;
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| 12 | ; This program is free software; you can redistribute it and/or
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| 13 | ; modify it under the terms of the GNU General Public License
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| 14 | ; as published by the Free Software Foundation, in version 3 of the
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| 15 | ; License.
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| 16 | ;
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| 17 | ; This program is distributed in the hope that it will be useful, but
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| 18 | ; WITHOUT ANY WARRANTY; without even the implied warranty of
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| 19 | ; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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| 20 | ; General Public License for more details.
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| 21 | ;
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| 22 | ; You should have received a copy of the GNU General Public License
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| 23 | ; along with this program; if not, see <https://www.gnu.org/licenses>.
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| 24 | ;
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| 25 | ; The contents of this file may alternatively be used under the terms
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| 26 | ; of the Common Development and Distribution License Version 1.0
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| 27 | ; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
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| 28 | ; in the VirtualBox distribution, in which case the provisions of the
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| 29 | ; CDDL are applicable instead of those of the GPL.
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| 30 | ;
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| 31 | ; You may elect to license modified versions of this file under the
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| 32 | ; terms and conditions of either the GPL or the CDDL or both.
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| 33 | ;
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| 34 | ; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
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| 35 | ;
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| 36 |
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| 37 | %include "bs3kit-template-header.mac"
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| 38 |
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| 39 |
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| 40 | ;;
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| 41 | ; 32-bit signed integer division.
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| 42 | ;
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| 43 | ; @returns DX:AX quotient, CX:BX remainder.
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| 44 | ; @param DX:AX Dividend.
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| 45 | ; @param CX:BX Divisor
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| 46 | ;
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| 47 | ; @uses Nothing.
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| 48 | ;
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| 49 | global $_?I4D
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| 50 | $_?I4D:
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| 51 | ;; @todo no idea if we're getting the negative division stuff right here according to what watcom expectes...
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| 52 | extern TODO_NEGATIVE_SIGNED_DIVISION
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| 53 | ; Move dividend into EDX:EAX
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| 54 | shl eax, 10h
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| 55 | mov ax, dx
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| 56 | sar dx, 0fh
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| 57 | movsx edx, dx
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| 58 |
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| 59 | ; Move divisor into ebx.
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| 60 | shl ebx, 10h
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| 61 | mov bx, cx
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| 62 |
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| 63 | ; Do it!
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| 64 | idiv ebx
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| 65 |
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| 66 | ; Reminder in to CX:BX
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| 67 | mov bx, dx
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| 68 | shr edx, 10h
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| 69 | mov cx, dx
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| 70 |
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| 71 | ; Quotient into DX:AX
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| 72 | mov edx, eax
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| 73 | shr edx, 10h
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| 74 |
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| 75 | %ifdef ASM_MODEL_FAR_CODE
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| 76 | retf
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| 77 | %else
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| 78 | ret
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| 79 | %endif
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| 80 |
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