Christophe Gisquet <[email protected]> writes:

> Hi,
>
> in my profiling, ff_sbr_apply accounts for ~12% of the decoding time,
> but it has a lot of inlining. The divisions I modify seem to account
> for ~5% of that, so precomputing them is interesting. Disassembly
> shows a gcc 4.6.2 on x86 64 with -funsafe-math-optimizations does not
> do this, while the attached patch does remove 2 such divisions. Not
> sure what part of these explanations is interesting to put in the log
> message.

Be careful.  That function has a comment warning about it being
numerically unstable.  Such a transformation might cause it to
blow up.

-- 
Måns Rullgård
[email protected]
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