Re: [PATCH 1/1] x86: fix text_poke

[H. Peter Anvin]

Mathieu Desnoyers wrote:
> > > +
> > As far as this is concerned, all you accomplish here is that gcc, if it 
> > wants to re-use the %al value, will copy it into another register before 
> > doing your imv_conv_end().
>
> Exactly, and by doing so, it will have to add instructions (mov, push..)
> in the instruction pattern I am looking for and therefore I will detect
> this and fall back on standard immediate values.

So what you're saying is you'll follow all the branches of code until 
you detect an immediate value (and eflags) kill.

Yes, that should work.  It's still ugly, and I have to say I find the 
complexity rather distasteful.  I am willing to be convinced it's worth 
it, but I would really like to see hard numbers.

Personally, I wouldn't be all that surprised if you lost more in 
constraining gcc scheduling than you gain.

	-hpa
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