alt.lang.asm Google Group

Re: AMD64: 32bit operations extend to 64 bits.

cr88...@hotmail.com (BGB / cr88192) — Mon, 04 Jan 2010 22:53:29 UT

yep, the high bits are zeroed with 32-bit operations.
note, however, that they are not zeroed with other-sized operations (8 or 16
bit).
in many cases, one may need to check particular instruction semantics for
maters of zeroing, especially if one gets into cases involving SSE
instructions, as not all operations are entirely consistent here.

Re: Debugger for AMD64?

fbkot...@myfairpoint.net (Frank Kotler) — Mon, 04 Jan 2010 22:44:26 UT

Sztacheta - jozeksztacheta wrote... but the clax86 moderation software
ate his post (for some reason)
Try FDBG
[link]
Sorry to have dropped your post - hope I've got it right! Thanks!
Best,
Frank

Re: Debugger for AMD64?

cr88...@munged.microcosmotalk.com (BGB / cr88192) — Mon, 04 Jan 2010 22:25:16 UT

for which OS?...
if Windows, I am using WinDbg, but granted this is not a command-line
debugger.
still has support for disassembly, ...
for Linux, there is GDB...
I think there may be a Win64 port of GDB by now, but I have not checked.
I forget where exactly, but I think there was also a command-line debugger

AMD64: 32bit operations extend to 64 bits.

t...@is.invalid (David) — Mon, 04 Jan 2010 22:16:58 UT

Hello,
Pending my debugger question so I can test this stuff out....
Is it correct in my assumption that taken the instruction:
shr edx,2
will result in the high 32 bits of rdx being zero so I can turn around and
use rdx?
Also, would the following affectively zero the high 32 bits of a general
register rax:

Debugger for AMD64?

t...@is.invalid (David) — Mon, 04 Jan 2010 20:10:27 UT

Anyone know of a AMD64 compatible symdeb/debug (command line) type debugger?
I use them all the time to test instruction results. For i386 I use ddeb,
but don't know of an AMD64 version?

Re: Buon Natale

a...@b.c.invalid (io_x) — Mon, 04 Jan 2010 09:17:41 UT

"Herbert Kleebauer" <k...@unibwm.de> ha scritto nel messaggio
if at that address i specify:
(si==100, bp==09xx)
00000072 55 push bp ; U
00000073 58 pop ax ; X
00000074 56 push si ; V
00000075 5A pop dx ; Z
00000076 53 push bx ; S (not used)

Announce: Introducing CRUDASM3 (new disassembler with full source code)

wrschlan...@gmail.com (Willow) — Sun, 03 Jan 2010 13:47:39 UT

Happy new year everyone!
It's been nearly a year and a half since I first released CRUDASM1, a
disassembler written entirely by me that supported 16 and 32 bit x86
raw binary images and is available under GPL 3.0.
After some discussion at this newsgroup, people found bugs and this
motivated me to rewrite it without the bugs, into CRUDASM2 a little

Re: Buon Natale

k...@unibwm.de (Herbert Kleebauer) — Sun, 03 Jan 2010 08:57:47 UT

io_x wrote:
I didn't say your code but your greetings crashes when executed.
When I disassemble the text:
------------------------------ ------------
Buon Natale
Merry Christmas to all!
------------------------------ ------------
I get:
0100 inc.w r1 (42)
0101 bne.b $0172 (75 6f)

Re: Buon Natale

a...@b.c.invalid (io_x) — Sat, 02 Jan 2010 06:37:31 UT

"Herbert Kleebauer" <k...@unibwm.de> ha scritto nel messaggio
yes possibily i'm not much sure on "ah=0Eh|int 10h"
this below here not segfault, and print the strings in a cmd window
where "bcc32" is the Borland C and C++ compiler 32bit
------------------------------ -------------
; nasmw -fobj this.asm

Re: multithreading in Asm

james.harri...@munged.microcosmotalk.com (James Harris) — Fri, 01 Jan 2010 01:26:45 UT

On 31 Dec 2009, 23:11, Qyz <questione...@MUNGED.microcosm otalk.com>
wrote:
I've not tried it but you may find posix threads available for various
operating systems.
James

Re: Buon Natale

fbkot...@myfairpoint.net (Frank Kotler) — Tue, 29 Dec 2009 23:40:57 UT

Well, the wind blew and the power went out, so I had a chance to boot
dos and try this. Even trickier than it appears! In DEBUG, it waits for
a key and doesn't print anything! I'll have to study this... Thanks,
Herbert!
Best,
Frank

Re: Pushad with GAS?

rugx...@gmail.com (Rugxulo) — Tue, 29 Dec 2009 05:12:06 UT

Hi,
I don't really use GAS directly much either. But ".intel_syntax
noprefix" seems to support "pushad" fine. Disassembling with "objdump -
d" seems to show "pusha" regardless of mode. And yes, "pushal" seems
to work in AT&T mode. Worst case scenario, you can always hardcode the
".byte 0x60". ^_^

Re: Buon Natale

k...@unibwm.de (Herbert Kleebauer) — Mon, 28 Dec 2009 13:23:42 UT

It doesn't matter what "everybody" knows. It only matters what the
CPU thinks. Just ask your CPU yourself. But you have to do this in
an OS which allows the CPU to give an uncensored answer (real mode
DOS instead of protected mode Linux). I have converted the question
to NASM syntax, so go ahead and feed the question to the CPU and

Re: Buon Natale

fbkot...@myfairpoint.net (Frank Kotler) — Sun, 27 Dec 2009 19:14:03 UT

...
Right! Everybody knows an x86 CPU prefers Motorola syntax! Oh, wait...
Best,
Frank

Re: Buon Natale

a...@b.c.invalid (io_x) — Sun, 27 Dec 2009 07:30:23 UT

"Herbert Kleebauer" <k...@unibwm.de> ha scritto nel messaggio
i like what is easy [for me], and loops