VirtualBox

source: vbox/trunk/src/VBox/Runtime/math/floor.asm@ 3460

Last change on this file since 3460 was 2988, checked in by vboxsync, 18 years ago

InnoTek -> innotek part 4: more miscellaneous files.

  • Property svn:keywords set to Id
File size: 1.8 KB
Line 
1; $Id: floor.asm 2988 2007-06-01 17:36:09Z vboxsync $
2;; @file
3; innotek Portable Runtime - No-CRT floor - AMD64 & X86.
4;
5
6;
7; Copyright (C) 2006-2007 innotek GmbH
8;
9; This file is part of VirtualBox Open Source Edition (OSE), as
10; available from http://www.virtualbox.org. This file is free software;
11; you can redistribute it and/or modify it under the terms of the GNU
12; General Public License as published by the Free Software Foundation,
13; in version 2 as it comes in the "COPYING" file of the VirtualBox OSE
14; distribution. VirtualBox OSE is distributed in the hope that it will
15; be useful, but WITHOUT ANY WARRANTY of any kind.
16;
17; If you received this file as part of a commercial VirtualBox
18; distribution, then only the terms of your commercial VirtualBox
19; license agreement apply instead of the previous paragraph.
20;
21
22%include "iprt/asmdefs.mac"
23
24BEGINCODE
25
26%ifdef __AMD64__
27 %define _SP rsp
28 %define _BP rbp
29 %define _S 8
30%else
31 %define _SP esp
32 %define _BP ebp
33 %define _S 4
34%endif
35
36;;
37; Compute the largest integral value not greater than rd.
38; @returns 32-bit: st(0) 64-bit: xmm0
39; @param rd 32-bit: [ebp + 8] 64-bit: xmm0
40BEGINPROC RT_NOCRT(floor)
41 push _BP
42 mov _BP, _SP
43 sub _SP, 10h
44
45%ifdef __AMD64__
46 movsd [_SP], xmm0
47 fld qword [_SP]
48%else
49 fld qword [_BP + _S*2]
50%endif
51
52 ; Make it round down by modifying the fpu control word.
53 fstcw [_BP - 10h]
54 mov eax, [_BP - 10h]
55 or eax, 00400h
56 and eax, 0f7ffh
57 mov [_BP - 08h], eax
58 fldcw [_BP - 08h]
59
60 ; Round ST(0) to integer.
61 frndint
62
63 ; Restore the fpu control word.
64 fldcw [_BP - 10h]
65
66%ifdef __AMD64__
67 fstp qword [_SP]
68 movsd xmm0, [_SP]
69%endif
70 leave
71 ret
72ENDPROC RT_NOCRT(floor)
73
Note: See TracBrowser for help on using the repository browser.

© 2024 Oracle Support Privacy / Do Not Sell My Info Terms of Use Trademark Policy Automated Access Etiquette