[Qemu-devel] Questions on "hidden" functions in QEMU source code

[Qemu-devel] Questions on "hidden" functions in QEMU source code

[Jun Koi]

Hi,

I am looking at the source code of QEMU, and there are some mystery to
me: some functions are not defined anywhere.

For example, functions like compute_all_incb() and compute_c_incl() in
target-i386/op.c are never defined anywhere.

So how the compilation process generates these functions?

Another question: micro-op are defined as OPPROTO, but OPPROTO is
actually defined as empty in dyngen-exec.h

#define OPPROTO

So what is the point of using OPPROTO here? I am sure that there is a
good reason to do that, but cannot figure it out.

Many thanks,
Jun

Re: [Qemu-devel] Questions on "hidden" functions in QEMU source code

[Stuart Brady]

On Tue, Oct 16, 2007 at 05:28:24PM +0900, Jun Koi wrote:
> For example, functions like compute_all_incb() and compute_c_incl() in
> target-i386/op.c are never defined anywhere.

compute_all_inc* are defined in ops_template.h:~171.  You'll notice that 
ops_template.h is included four times from op.c.

> Another question: micro-op are defined as OPPROTO, but OPPROTO is
> actually defined as empty in dyngen-exec.h
> 
> #define OPPROTO
> 
> So what is the point of using OPPROTO here? I am sure that there is a
> good reason to do that, but cannot figure it out.

Presumably so that attributes can be defined later if they're needed.

Cheers,
-- 
Stuart Brady

Re: [Qemu-devel] Questions on "hidden" functions in QEMU source code

[Johannes Schindelin]

Hi,

On Tue, 16 Oct 2007, Stuart Brady wrote:

> On Tue, Oct 16, 2007 at 05:28:24PM +0900, Jun Koi wrote:
> > For example, functions like compute_all_incb() and compute_c_incl() in
> > target-i386/op.c are never defined anywhere.
> 
> compute_all_inc* are defined in ops_template.h:~171.  You'll notice that 
> ops_template.h is included four times from op.c.

If you wonder why it is included four times, this might help:

http://libvncserver.sourceforge.net/qemu/qemu-templates-ala-Fabrice.txt

Hth,
Dscho

Re: [Qemu-devel] Questions on "hidden" functions in QEMU source code

[Jun Koi]

On 10/16/07, Johannes Schindelin <Johannes.Schindelin@gmx.de> wrote:
> Hi,
>
> On Tue, 16 Oct 2007, Stuart Brady wrote:
>
> > On Tue, Oct 16, 2007 at 05:28:24PM +0900, Jun Koi wrote:
> > > For example, functions like compute_all_incb() and compute_c_incl() in
> > > target-i386/op.c are never defined anywhere.
> >
> > compute_all_inc* are defined in ops_template.h:~171.  You'll notice that
> > ops_template.h is included four times from op.c.
>
> If you wonder why it is included four times, this might help:
>
> http://libvncserver.sourceforge.net/qemu/qemu-templates-ala-Fabrice.txt
>

Now it is clear that those stuffs are generated by dyngen, thanks.

But still it it not obvious to me what is the purpose of "OPPROTO"
when defining micro-ops. May you elaborate this a bit more?

Many thanks,
Jun
> Hth,
> Dscho
>
>
>
>

Re: [Qemu-devel] Questions on "hidden" functions in QEMU source code

[Rob Landley]

On Tuesday 16 October 2007 9:19:36 am Johannes Schindelin wrote:
> If you wonder why it is included four times, this might help:
>
> http://libvncserver.sourceforge.net/qemu/qemu-templates-ala-Fabrice.txt

Is that linked from qemu.org/user-doc.html somewhere?

Rob
-- 
"One of my most productive days was throwing away 1000 lines of code."
  - Ken Thompson.