Date: Tue, 14 Jul 1998 11:36:18 -0400 From: Brian Cully <shmit@kublai.com> To: Steven Kehlet <kehlet@dt.wdc.com>, Jonny <jvz@ns.nternet.net> Cc: hackers@FreeBSD.ORG Subject: Re: Assembly.. Message-ID: <19980714113618.23544@kublai.com> In-Reply-To: <Pine.GSO.3.96.980713171508.18643G-100000@hydra-X4>; from Steven Kehlet on Mon, Jul 13, 1998 at 05:55:06PM -0700 References: <Pine.BSF.3.96.980713191737.12005A-100000@ns.nternet.net> <Pine.GSO.3.96.980713171508.18643G-100000@hydra-X4>
next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, Jul 13, 1998 at 05:55:06PM -0700, Steven Kehlet wrote:
> (gdb) disass main
> Dump of assembler code for function main:
> 0x15b0 <main>: pushl $0x0
> 0x15b2 <main+2>: leal 0x1,%eax
> 0x15b8 <main+8>: pushl 0x1234
> 0x15be <main+14>: lcall 0x7,0x0
> End of assembler dump.
> (gdb)
>
> ... just like it should. Oh yeah, though, there's one more weird thing.
> Note that "pushl 0x1234" I stuck in there. I found you need to
> push this garbage value onto the stack before doing the lcall.
I noticed the same thing when I was doing it with int $0x80, and not
lcall. What is the purpose of that value? From looking in
/sys/i386/i386/trap.c it appears to be ignored:
params = (caddr_t)frame.tf_esp + sizeof(int);
Did it used to be used to hold an RTA or something?
-bjc
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?19980714113618.23544>