Hi,

On Thu, Apr 5, 2012 at 1:29 PM, Christophe Gisquet
<[email protected]> wrote:
> 2012/4/5 Ronald S. Bultje <[email protected]>:
>> This looks OK. Is there a performance benefit? I assume there isn't
>> anything measurable, because the overhead is relatively low?
>
> Yes, the split between prescaled/non-scaled cases shaves like 3 cycles
> per call, and leads to a result within measure noise.
>
> However, this makes it clear that such a distinction should be made
> (I'm thinking of neon code here). For the SSSE3 case, the non-scaled
> version is ~217 cycles, and the prescaled (producing identical
> results) is ~141.
>
>> As for the code, do please document the arrays in rv34dsp.h, so we
>> don't have to look at the code to figure out what the difference
>> between [0][0] and [1][1] is.
>
> Done. The commit message is also more verbose, but in the end, it
> would be interesting to know if it is good enough for someone
> implementing code based on this.
>
> Another (clearer?) solution would be to have:
> rv40_weight_func rv40_nonscaled_biweight[2];
> rv40_weight_func rv40_prescaled_biweight[2];
> in RV34DSPContext
> and have function pointers set to the correct values in RV34DecContex.

No, this is OK. LGTM.

Ronald
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