diff options
Diffstat (limited to 'src/VBox/Runtime/common/math/watcom/I8D-x86-32.asm')
| -rw-r--r-- | src/VBox/Runtime/common/math/watcom/I8D-x86-32.asm | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/math/watcom/I8D-x86-32.asm b/src/VBox/Runtime/common/math/watcom/I8D-x86-32.asm new file mode 100644 index 00000000..2aa02520 --- /dev/null +++ b/src/VBox/Runtime/common/math/watcom/I8D-x86-32.asm @@ -0,0 +1,108 @@ +; $Id: I8D-x86-32.asm $ +;; @file +; BS3Kit - 32-bit Watcom C/C++, 64-bit signed integer division. +; + +; +; Copyright (C) 2007-2023 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 + +extern __U8D + + +;; +; 64-bit signed integer division. +; +; @returns EDX:EAX Quotient, ECX:EBX Remainder. +; @param EDX:EAX Dividend. +; @param ECX:EBX Divisor +; +global __I8D +__I8D: + ; + ; We use __U8D to do the work, we take care of the signedness. + ; + or edx, edx + js .negative_dividend + + or ecx, ecx + js .negative_divisor_positive_dividend + jmp __U8D + + +.negative_divisor_positive_dividend: + ; negate the divisor, do unsigned division, and negate the quotient. + neg ecx + neg ebx + sbb ecx, 0 + + call __U8D + + neg edx + neg eax + sbb edx, 0 + ret + +.negative_dividend: + neg edx + neg eax + sbb edx, 0 + + or ecx, ecx + js .negative_dividend_negative_divisor + +.negative_dividend_positive_divisor: + ; negate the dividend (above), do unsigned division, and negate both quotient and remainder + call __U8D + + neg edx + neg eax + sbb edx, 0 + +.return_negated_remainder: + neg ecx + neg ebx + sbb ecx, 0 + ret + +.negative_dividend_negative_divisor: + ; negate both dividend (above) and divisor, do unsigned division, and negate the remainder. + neg ecx + neg ebx + sbb ecx, 0 + + call __U8D + jmp .return_negated_remainder + |