Re: [patch 4/7] Immediate Values - i386 Optimization

[Andi Kleen]

On Tue, Sep 18, 2007 at 03:29:50PM -0700, Jeremy Fitzhardinge wrote:
> Andi Kleen wrote:
> > Jeremy Fitzhardinge <jeremy@xxxxxxxx> writes:
> >   
> >> It's a pity that gas seems to generate plain 0x90 nops rather than
> >> long-nop forms here.  I thought it could do that.
> >>     
> >
> > .p2align does it
> 
> Just .p2align?  Not align, balign, org or skip?  Seems... strange.

The problem is that you cannot always safely jump into the middle of the 
longer form nops. So I suppose they didn't risk breakage on older
code relying on this.

-Andi
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