digitalmars.D - How to mov EAX, &func?
- "Mehrdad" <wfunction hotmail.com> May 15 2012
- Gor Gyolchanyan <gor.f.gyolchanyan gmail.com> May 15 2012
- deadalnix <deadalnix gmail.com> May 15 2012
- ponce <spam spam.org> May 15 2012
- =?UTF-8?B?QWxleCBSw7hubmUgUGV0ZXJzZW4=?= <alex lycus.org> May 15 2012
- ponce <spam spam.org> May 15 2012
- "Mehrdad" <wfunction hotmail.com> May 15 2012
- Walter Bright <newshound2 digitalmars.com> May 16 2012
- Walter Bright <newshound2 digitalmars.com> May 16 2012
- "Mehrdad" <wfunction hotmail.com> May 16 2012
- "Mehrdad" <wfunction hotmail.com> May 16 2012
- "Mehrdad" <wfunction hotmail.com> May 16 2012
How do get the address of a function in naked assembly code?
void foo()
{
asm
{
naked;
mov EAX, &foo;
}
}
This doesn't work...
May 15 2012
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I think I had that one before. Try this one:
void foo()
{
void* foopt = cast(void*)&foo;
asm
{
naked;
mov EAX fooptr;
}
}
On Tue, May 15, 2012 at 11:33 PM, Mehrdad <wfunction hotmail.com> wrote:
How do get the address of a function in naked assembly code?
void foo()
{
asm
{
naked;
mov EAX, &foo;
}
}
This doesn't work...
--
Bye,
Gor Gyolchanyan.
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I think I had that one before. Try this one:<div>void foo()</div><div>{</di=
v><div>=C2=A0 =C2=A0 void* foopt =3D cast(void*)&foo;</div><div>=C2=A0 =
=C2=A0 asm</div><div>=C2=A0 =C2=A0 {</div><div>=C2=A0 =C2=A0 =C2=A0 =C2=A0 =
naked;</div><div>=C2=A0 =C2=A0 =C2=A0 =C2=A0 mov EAX fooptr;</div><div>
=C2=A0 =C2=A0 }<br>}<br><div><br><div class=3D"gmail_quote">On Tue, May 15,=
2012 at 11:33 PM, Mehrdad <span dir=3D"ltr"><<a href=3D"mailto:wfunctio=
n hotmail.com" target=3D"_blank">wfunction hotmail.com</a>></span> wrote=
:<br><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-le=
ft:1px #ccc solid;padding-left:1ex">
How do get the address of a function in naked assembly code?<br>
<br>
void foo()<br>
{<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0asm<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0{<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0naked;<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0mov EAX, &foo;<=
br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0}<br>
}<br>
<br>
This doesn't work...<br>
</blockquote></div><br><br clear=3D"all"><div><br></div>-- <br>Bye,<br>Gor =
Gyolchanyan.<br>
</div></div>
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May 15 2012
=?UTF-8?B?QWxleCBSw7hubmUgUGV0ZXJzZW4=?= <alex lycus.org> On 15-05-2012 22:51, Gor Gyolchanyan wrote:I think I had that one before. Try this one: void foo() { void* foopt = cast(void*)&foo; asm { naked; mov EAX fooptr; } } On Tue, May 15, 2012 at 11:33 PM, Mehrdad <wfunction hotmail.com <mailto:wfunction hotmail.com>> wrote: How do get the address of a function in naked assembly code? void foo() { asm { naked; mov EAX, &foo; } } This doesn't work... -- Bye, Gor Gyolchanyan.
That's not naked inline asm, though. Something like this might work: void foo() { asm { naked; mox EAX, dword ptr foo; /* whatever... */ } } -- Alex Rønne Petersen alex lycus.org http://lycus.org
May 15 2012
Le 15/05/2012 21:33, Mehrdad a écrit :How do get the address of a function in naked assembly code? void foo() { asm { naked; mov EAX, &foo; } } This doesn't work...
As it is naked, mov EAX, EIP; is enough.
May 15 2012
Le 15/05/2012 23:27, deadalnix a écrit :mov EAX, EIP; is enough.
I think this is illegal in assembly, try to call a label in your function then pop. void* selfAddress() // actually tested { asm { naked; call my_label; my_label: pop EAX; sub EAX, 5; ret; } }
May 15 2012
On 15-05-2012 23:27, deadalnix wrote:Le 15/05/2012 21:33, Mehrdad a écrit :How do get the address of a function in naked assembly code? void foo() { asm { naked; mov EAX, &foo; } } This doesn't work...
As it is naked, mov EAX, EIP; is enough.
I suspect he wanted a solution where he could load an arbitrary function's address. -- Alex Rønne Petersen alex lycus.org http://lycus.org
May 15 2012
Le 15/05/2012 23:58, Alex Rønne Petersen a écrit :I suspect he wanted a solution where he could load an arbitrary function's address.
I'm also searching for a way to get a label address from inline assembly. This would be useful for hard-coded jumptables.
May 15 2012
On Tuesday, 15 May 2012 at 21:58:56 UTC, Alex Rønne Petersen wrote:On 15-05-2012 23:27, deadalnix wrote:Le 15/05/2012 21:33, Mehrdad a écrit :How do get the address of a function in naked assembly code? void foo() { asm { naked; mov EAX, &foo; } } This doesn't work...
As it is naked, mov EAX, EIP; is enough.
I suspect he wanted a solution where he could load an arbitrary function's address.
indeed
May 15 2012
On 5/15/2012 12:33 PM, Mehrdad wrote:How do get the address of a function in naked assembly code? void foo() { asm { naked; mov EAX, &foo; } } This doesn't work...
I know, but also be aware that even if it did work, it would not work in the presence of PIC code and shared libraries. It's best if you stick to using D code to get the address of a function, which accounts for all these variations and wierdness.
May 16 2012
On 5/16/2012 2:40 AM, Mehrdad wrote:The trouble with 'sticking to D code' is that, well, I can't... it's naked...
Just insert an asm call to a function that returns the address of foo.
May 16 2012
On Wednesday, 16 May 2012 at 07:05:10 UTC, Walter Bright wrote:On 5/15/2012 12:33 PM, Mehrdad wrote:How do get the address of a function in naked assembly code? void foo() { asm { naked; mov EAX, &foo; } } This doesn't work...
I know, but also be aware that even if it did work, it would not work in the presence of PIC code and shared libraries. It's best if you stick to using D code to get the address of a function, which accounts for all these variations and wierdness.
Yeah I know, but currently shared libraries are the least of my worries. The trouble with 'sticking to D code' is that, well, I can't... it's naked...
May 16 2012
On Wednesday, 16 May 2012 at 09:40:08 UTC, Mehrdad wrote:Yeah I know, but currently shared libraries are the least of my worries.
Or position-independent code for that matter, although I'd be more concerned with this than the former.
May 16 2012
On Wednesday, 16 May 2012 at 18:17:50 UTC, Walter Bright wrote:On 5/16/2012 2:40 AM, Mehrdad wrote:The trouble with 'sticking to D code' is that, well, I can't... it's naked...
Just insert an asm call to a function that returns the address of foo.
Hmmm... interesting idea. Not a real fan of this solution, since it's extra code, and it involves a function call (and I was trying to avoid function calls in this code, since it's going to be in a boot-sector-like thing). But I think it'll work, thanks...
May 16 2012