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Re: Extending constraints using register subclasses
Thank you Andrew, I wasn't aware of that. Will be going that way.
Just out of curiosity, was there something flawed in the way I took before?
Meaning, could have been done that way, but my code was wrong somewhere?
- Jamie
----- Original Message ----
> From: Andrew Pinski <pinskia@gmail.com>
> To: Jamie Prescott <jpresss@yahoo.com>
> Cc: gcc@gcc.gnu.org
> Sent: Monday, May 11, 2009 4:47:57 PM
> Subject: Re: Extending constraints using register subclasses
>
> On Mon, May 11, 2009 at 4:45 PM, Jamie Prescott wrote:
> >
> > Hi!
> > I wanted to add finer (one per) register subclasses, so that I can more finely
> control
> > the register placement inside the inline assembly.
>
> You don't need that.
> You can just use asm("registername") on variables.
> like so:
>
> int f(int a)
> {
> register int r0 __asm__("r0");
> asm("use %0": "+r"(r0) );
> }
>
> Thanks,
> Andrew Pinski