Re: [patch] Fix of the CPU bottleneck in pack_vector

[Yuri]

On 01/25/2012 06:49, Akim Demaille wrote:

> Hi Yuri,

Hi Akim,
> Wow!  You just aroused my curiosity!  Could you give us some
> indication on the kind of use you make of Bison?  Running
> the backend is sooooo expensive, that I would have bet that
> such optimization would be completely impossible to feel.

I actually don't use bison, I was playing with the large testcases 
trying to see how capable bison is in recognizing some lexical patterns.
I am attaching the testcase, that runs in 11 sec with my patch, and in 
maybe 50X that without.

> > Please let me know if you find any problem with the patch.
> Now the problem would be how to apply it.  It is quite short, but
> I doubt it falls under the "trivial change" clause.  So either
I agree that this is not a trivial change, though it's a very local change.
> one of us would have to rewrite it, or you would have to file some
> legal paperwork for the FSF.

No problem. What kind of legal paperwork should I file? I don't foresee 
any legal issues with this.

Thank you,
Yuri

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