[FFmpeg-devel] [PATCH 1/9] SBR DSP x86: implement SSE qmf_pre_shuffle

Christophe Gisquet christophe.gisquet at gmail.com
Sat Apr 6 11:26:54 CEST 2013


2013/4/5 Michael Niedermayer <michaelni at gmx.at>:
> using simpler memory indexing ([r2q + n*mmsize] and [zq])
> and incremeanting them seperately seems 1-2 cpu cycles faster here

In general, and most particularly here, could you provide whatever
form (except machine code ;) of the code you tested?

Sometimes, if it's just a bit of guessing, it allows investigating by
not blindly pasting code. But here, it is a bit tedious because there
are several ways, and all require to recompute some offsets, which is
error-prone.

Thanks,
--
Christophe


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