| 1 | ; $Id: I8D-x86-32.asm 96407 2022-08-22 17:43:14Z vboxsync $
|
|---|
| 2 | ;; @file
|
|---|
| 3 | ; BS3Kit - 32-bit Watcom C/C++, 64-bit signed integer division.
|
|---|
| 4 | ;
|
|---|
| 5 |
|
|---|
| 6 | ;
|
|---|
| 7 | ; Copyright (C) 2007-2022 Oracle and/or its affiliates.
|
|---|
| 8 | ;
|
|---|
| 9 | ; This file is part of VirtualBox base platform packages, as
|
|---|
| 10 | ; available from https://www.virtualbox.org.
|
|---|
| 11 | ;
|
|---|
| 12 | ; This program is free software; you can redistribute it and/or
|
|---|
| 13 | ; modify it under the terms of the GNU General Public License
|
|---|
| 14 | ; as published by the Free Software Foundation, in version 3 of the
|
|---|
| 15 | ; License.
|
|---|
| 16 | ;
|
|---|
| 17 | ; This program is distributed in the hope that it will be useful, but
|
|---|
| 18 | ; WITHOUT ANY WARRANTY; without even the implied warranty of
|
|---|
| 19 | ; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|---|
| 20 | ; General Public License for more details.
|
|---|
| 21 | ;
|
|---|
| 22 | ; You should have received a copy of the GNU General Public License
|
|---|
| 23 | ; along with this program; if not, see <https://www.gnu.org/licenses>.
|
|---|
| 24 | ;
|
|---|
| 25 | ; The contents of this file may alternatively be used under the terms
|
|---|
| 26 | ; of the Common Development and Distribution License Version 1.0
|
|---|
| 27 | ; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
|
|---|
| 28 | ; in the VirtualBox distribution, in which case the provisions of the
|
|---|
| 29 | ; CDDL are applicable instead of those of the GPL.
|
|---|
| 30 | ;
|
|---|
| 31 | ; You may elect to license modified versions of this file under the
|
|---|
| 32 | ; terms and conditions of either the GPL or the CDDL or both.
|
|---|
| 33 | ;
|
|---|
| 34 | ; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
|
|---|
| 35 | ;
|
|---|
| 36 |
|
|---|
| 37 | %include "iprt/asmdefs.mac"
|
|---|
| 38 |
|
|---|
| 39 |
|
|---|
| 40 | BEGINCODE
|
|---|
| 41 |
|
|---|
| 42 | extern __U8D
|
|---|
| 43 |
|
|---|
| 44 |
|
|---|
| 45 | ;;
|
|---|
| 46 | ; 64-bit signed integer division.
|
|---|
| 47 | ;
|
|---|
| 48 | ; @returns EDX:EAX Quotient, ECX:EBX Remainder.
|
|---|
| 49 | ; @param EDX:EAX Dividend.
|
|---|
| 50 | ; @param ECX:EBX Divisor
|
|---|
| 51 | ;
|
|---|
| 52 | global __I8D
|
|---|
| 53 | __I8D:
|
|---|
| 54 | ;
|
|---|
| 55 | ; We use __U8D to do the work, we take care of the signedness.
|
|---|
| 56 | ;
|
|---|
| 57 | or edx, edx
|
|---|
| 58 | js .negative_dividend
|
|---|
| 59 |
|
|---|
| 60 | or ecx, ecx
|
|---|
| 61 | js .negative_divisor_positive_dividend
|
|---|
| 62 | jmp __U8D
|
|---|
| 63 |
|
|---|
| 64 |
|
|---|
| 65 | .negative_divisor_positive_dividend:
|
|---|
| 66 | ; negate the divisor, do unsigned division, and negate the quotient.
|
|---|
| 67 | neg ecx
|
|---|
| 68 | neg ebx
|
|---|
| 69 | sbb ecx, 0
|
|---|
| 70 |
|
|---|
| 71 | call __U8D
|
|---|
| 72 |
|
|---|
| 73 | neg edx
|
|---|
| 74 | neg eax
|
|---|
| 75 | sbb edx, 0
|
|---|
| 76 | ret
|
|---|
| 77 |
|
|---|
| 78 | .negative_dividend:
|
|---|
| 79 | neg edx
|
|---|
| 80 | neg eax
|
|---|
| 81 | sbb edx, 0
|
|---|
| 82 |
|
|---|
| 83 | or ecx, ecx
|
|---|
| 84 | js .negative_dividend_negative_divisor
|
|---|
| 85 |
|
|---|
| 86 | .negative_dividend_positive_divisor:
|
|---|
| 87 | ; negate the dividend (above), do unsigned division, and negate both quotient and remainder
|
|---|
| 88 | call __U8D
|
|---|
| 89 |
|
|---|
| 90 | neg edx
|
|---|
| 91 | neg eax
|
|---|
| 92 | sbb edx, 0
|
|---|
| 93 |
|
|---|
| 94 | .return_negated_remainder:
|
|---|
| 95 | neg ecx
|
|---|
| 96 | neg ebx
|
|---|
| 97 | sbb ecx, 0
|
|---|
| 98 | ret
|
|---|
| 99 |
|
|---|
| 100 | .negative_dividend_negative_divisor:
|
|---|
| 101 | ; negate both dividend (above) and divisor, do unsigned division, and negate the remainder.
|
|---|
| 102 | neg ecx
|
|---|
| 103 | neg ebx
|
|---|
| 104 | sbb ecx, 0
|
|---|
| 105 |
|
|---|
| 106 | call __U8D
|
|---|
| 107 | jmp .return_negated_remainder
|
|---|
| 108 |
|
|---|
