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