summaryrefslogtreecommitdiffstats
path: root/src/VBox/Runtime/common/math/watcom/U8M-I8M-x86-32.asm
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 03:01:46 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 03:01:46 +0000
commitf8fe689a81f906d1b91bb3220acde2a4ecb14c5b (patch)
tree26484e9d7e2c67806c2d1760196ff01aaa858e8c /src/VBox/Runtime/common/math/watcom/U8M-I8M-x86-32.asm
parentInitial commit. (diff)
downloadvirtualbox-upstream.tar.xz
virtualbox-upstream.zip
Adding upstream version 6.0.4-dfsg.upstream/6.0.4-dfsgupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/VBox/Runtime/common/math/watcom/U8M-I8M-x86-32.asm')
-rw-r--r--src/VBox/Runtime/common/math/watcom/U8M-I8M-x86-32.asm77
1 files changed, 77 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/math/watcom/U8M-I8M-x86-32.asm b/src/VBox/Runtime/common/math/watcom/U8M-I8M-x86-32.asm
new file mode 100644
index 00000000..71dd8cc6
--- /dev/null
+++ b/src/VBox/Runtime/common/math/watcom/U8M-I8M-x86-32.asm
@@ -0,0 +1,77 @@
+; $Id: U8M-I8M-x86-32.asm $
+;; @file
+; BS3Kit - 32-bit Watcom C/C++, 64-bit unsigned integer division.
+;
+
+;
+; Copyright (C) 2007-2019 Oracle Corporation
+;
+; This file is part of VirtualBox Open Source Edition (OSE), as
+; available from http://www.virtualbox.org. This file is free software;
+; you can redistribute it and/or modify it under the terms of the GNU
+; General Public License (GPL) as published by the Free Software
+; Foundation, in version 2 as it comes in the "COPYING" file of the
+; VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+; hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+;
+; The contents of this file may alternatively be used under the terms
+; of the Common Development and Distribution License Version 1.0
+; (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+; VirtualBox OSE 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.
+;
+
+%include "iprt/asmdefs.mac"
+
+
+BEGINCODE
+
+
+;;
+; 64-bit signed & unsigned integer multiplication.
+;
+; @returns EDX:EAX product
+; @param EDX:EAX Factor #1.
+; @param ECX:EBX Factor #2.
+; @uses ECX, EBX
+;
+global __U8M
+__U8M:
+global __I8M
+__I8M:
+ ;
+ ; See if this is a pure 32-bit multiplication. We might get lucky.
+ ;
+ test edx, edx
+ jnz .complicated
+ test ecx, ecx
+ jnz .complicated
+
+ mul ebx ; eax * ebx -> edx:eax
+ ret
+
+.complicated:
+ push eax
+ push edx
+
+ ; ecx = F1.lo * F2.hi (edx contains overflow here can be ignored)
+ mul ecx
+ mov ecx, eax
+
+ ; ecx += F1.hi * F2.lo (edx can be ignored again)
+ pop eax
+ mul ebx
+ add ecx, eax
+
+ ; edx:eax = F1.lo * F2.lo
+ pop eax
+ mul ebx
+
+ ; Add ecx to the high part (edx).
+ add edx, ecx
+
+ ret
+