Re: regparm guarantee

Re: regparm guarantee

[y2bismil]

Hi,

No, its not a problem of variable arguments.  There's no problem per se.  I'm
just asking if its guaranteed or if its one of those GCC 'hints' that may or may
not be done.  


Thanks,

Yamin

Quoting qinfeng.zhang@philips.com:

> Is it the problem of vararg?
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> y2bismil@engmail.uwaterloo.ca
> Sent by: 
> gcc-help-owner@gcc.gnu.org
> 2003-11-19 04:41
> 
>  
>         To:     GCC- help <gcc-help@gcc.gnu.org>
>         cc:     (bcc: Qinfeng Zhang/SHA/RESEARCH/PHILIPS)
>         Subject:        regparm guarantee
>         Classification: 
> 
> 
> 
> 
> 
> I was wondering if by specifying regparam for a function if it is 
> GUARANTEED
> that parameters passed to the function will be made via register.  I ask 
> this as
> I'm interfacing with an assembly written library which links to external 
> c-code.
>  When the assembly routines call c-function, there are some that are 
> stdcall,
> and some pass variables through register (they only pass 1 variable as far 
> as I
> can see in EAX).
> 
> Is there any way to explicitly say "use EAX for this parameter?" 
> >From the wording of the manual under 'function attributes', it doesn't 
> appear
> so.  But I might guess that it places the 1st paramter in EAX, second in 
> EBX,
> then ECX, EDX.
> 
> Thanks,
> 
> Yamin
> 
> ----------------------------------------
> This mail sent through www.mywaterloo.ca
> 
> 
> 




----------------------------------------
This mail sent through www.mywaterloo.ca

Re: regparm guarantee

[Kimmo Fredriksson]

On Wed, 19 Nov 2003 y2bismil@engmail.uwaterloo.ca wrote:

> Hi,
>
> No, its not a problem of variable arguments.  There's no problem per se.  I'm
> just asking if its guaranteed or if its one of those GCC 'hints' that may or may
> not be done.

I suppose it just a hint, that may (will?) be ignored. On the other hand,
see:

http://gcc.gnu.org/onlinedocs/gcc/Explicit-Reg-Vars.html#Explicit%20Reg%20Vars

Kimmo

>
>
> Thanks,
>
> Yamin
>
> Quoting qinfeng.zhang@philips.com:
>
> > Is it the problem of vararg?
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > y2bismil@engmail.uwaterloo.ca
> > Sent by:
> > gcc-help-owner@gcc.gnu.org
> > 2003-11-19 04:41
> >
> >
> >         To:     GCC- help <gcc-help@gcc.gnu.org>
> >         cc:     (bcc: Qinfeng Zhang/SHA/RESEARCH/PHILIPS)
> >         Subject:        regparm guarantee
> >         Classification:
> >
> >
> >
> >
> >
> > I was wondering if by specifying regparam for a function if it is
> > GUARANTEED
> > that parameters passed to the function will be made via register.  I ask
> > this as
> > I'm interfacing with an assembly written library which links to external
> > c-code.
> >  When the assembly routines call c-function, there are some that are
> > stdcall,
> > and some pass variables through register (they only pass 1 variable as far
> > as I
> > can see in EAX).
> >
> > Is there any way to explicitly say "use EAX for this parameter?"
> > >From the wording of the manual under 'function attributes', it doesn't
> > appear
> > so.  But I might guess that it places the 1st paramter in EAX, second in
> > EBX,
> > then ECX, EDX.
> >
> > Thanks,
> >
> > Yamin
> >
> > ----------------------------------------
> > This mail sent through www.mywaterloo.ca
> >
> >
> >
>
>
>
>
> ----------------------------------------
> This mail sent through www.mywaterloo.ca
>

Re: regparm guarantee

[y2bismil]

http://gcc.gnu.org/onlinedocs/gcc-3.3.1/gcc/Function-Attributes.html#Function%20Attributes
--regparm 

This is the section in question.  This is about parameter passing not variable
declaration.

Yamin

Quoting Kimmo Fredriksson <kfredrik@cs.joensuu.fi>:
> On Wed, 19 Nov 2003 y2bismil@engmail.uwaterloo.ca wrote:
> 
> > Hi,
> >
> > No, its not a problem of variable arguments.  There's no problem per se. 
> I'm
> > just asking if its guaranteed or if its one of those GCC 'hints' that may
> or may
> > not be done.
> 
> I suppose it just a hint, that may (will?) be ignored. On the other hand,
> see:
> 
> http://gcc.gnu.org/onlinedocs/gcc/Explicit-Reg-Vars.html#Explicit%20Reg%20Vars
> 
> Kimmo
> 
> >
> >
> > Thanks,
> >
> > Yamin
> >
> > Quoting qinfeng.zhang@philips.com:
> >
> > > Is it the problem of vararg?
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > y2bismil@engmail.uwaterloo.ca
> > > Sent by:
> > > gcc-help-owner@gcc.gnu.org
> > > 2003-11-19 04:41
> > >
> > >
> > >         To:     GCC- help <gcc-help@gcc.gnu.org>
> > >         cc:     (bcc: Qinfeng Zhang/SHA/RESEARCH/PHILIPS)
> > >         Subject:        regparm guarantee
> > >         Classification:
> > >
> > >
> > >
> > >
> > >
> > > I was wondering if by specifying regparam for a function if it is
> > > GUARANTEED
> > > that parameters passed to the function will be made via register.  I ask
> > > this as
> > > I'm interfacing with an assembly written library which links to external
> > > c-code.
> > >  When the assembly routines call c-function, there are some that are
> > > stdcall,
> > > and some pass variables through register (they only pass 1 variable as
> far
> > > as I
> > > can see in EAX).
> > >
> > > Is there any way to explicitly say "use EAX for this parameter?"
> > > >From the wording of the manual under 'function attributes', it doesn't
> > > appear
> > > so.  But I might guess that it places the 1st paramter in EAX, second in
> > > EBX,
> > > then ECX, EDX.
> > >
> > > Thanks,
> > >
> > > Yamin
> > >
> > > ----------------------------------------
> > > This mail sent through www.mywaterloo.ca
> > >
> > >
> > >
> >
> >
> >
> >
> > ----------------------------------------
> > This mail sent through www.mywaterloo.ca
> >
> 




----------------------------------------
This mail sent through www.mywaterloo.ca

regparm guarantee

[y2bismil]

I was wondering if by specifying regparam for a function if it is GUARANTEED
that parameters passed to the function will be made via register.  I ask this as
I'm interfacing with an assembly written library which links to external c-code.
 When the assembly routines call c-function, there are some that are stdcall,
and some pass variables through register (they only pass 1 variable as far as I
can see in EAX).

Is there any way to explicitly say "use EAX for this parameter?"  
From the wording of the manual under 'function attributes', it doesn't appear
so.  But I might guess that it places the 1st paramter in EAX, second in EBX,
then ECX, EDX.

Thanks,

Yamin

----------------------------------------
This mail sent through www.mywaterloo.ca