Re: [pcre-dev] Powerpc optimisation

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Author: Zoltán Herczeg
Date:  
To: Frederic Bonnard
CC: pcre-dev
Subject: Re: [pcre-dev] Powerpc optimisation
Hi Frederic,

the sljit compiler uses SSE2 only for floating point computation, and not for SIMD computation. PCRE-JIT only uses integer computation, so it does not even use the SSE2 part.

We had discussions about using SIMD for regex matching, but nothing was implemented so far. The suggestion was using SIMD for checking character ranges, but the code seemed a bit complicated.

Anyway, adding some SIMD stuff to SLJIT has makes sense in the long run, especially if we would have a use case for it. The challenge is finding the appropriate instructions forms. I am open to suggestions. I recently added an overview to the sljit compiler where I described its design concepts:

http://sourceforge.net/p/sljit/code/HEAD/tree/doc/overview.txt

We should invent something to SIMD.

Also, if you have perf issues with PCRE-JIT on PPC (e.g. much slower on certain patterns than x86), just let me know.

Regards,
Zoltan

Frederic Bonnard <frediz@???> írta:
>Hi,
>I've seen that on x86, sljit can use SSE instructions. But on Powerpc, there's
>no use of Altivec/VSX ; I'm not an expert, but would this be bringing something in
>term of performance ; at least, does it just make sense ?
>Thanks,
>
>F.
>--
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