[FFmpeg-devel] [PATCH v2 161/162] avcodec/mpegaudiodec: Hardcode tables to save space

[Michael Niedermayer]

On Fri, Nov 20, 2020 at 08:33:26AM +0100, Andreas Rheinhardt wrote:
> The csa_tables (which always consist of 32 entries of four byte each,
> but the type depends upon whether the decoder is fixed or
> floating-point) are currently initialized once during decoder
> initialization; yet it turns out that this is actually no benefit: The
> code used to initialize these tables takes up 153 (fixed point) and 122
> (floating point) bytes when compiled with GCC 9.3 with -O3 on x64, so it
> is better to just hardcode these tables.
> 
> Essentially the same applies to the is_tables: They have a size or 128
> each and the code to initialize them occupies 149 (fixed point) resp.
> 140 (floating point) bytes. So hardcode them, too.

Is it intended not to use CONFIG_HARDCODED_TABLES ?

also if the code generating the tables is removed then it should be made
easy to re-build the tables. That would be in the spirit of the *GPL
(to be able to change and rebuild a binary\H table 
 for potentially a different use)

thx

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

The worst form of inequality is to try to make unequal things equal.
-- Aristotle
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