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Commit Graph

3 Commits

Author SHA1 Message Date
Andreas Rheinhardt
d5d1c697bd avcodec/mpegaudio_tablegen: Make exponential LUT shared
Both the fixed as well as the floating point mpegaudio decoders use
LUTs of type int8_t and uint32_t with 32K entries each; these tables
are completely the same, yet they are not shared. This commit makes
them shared. When both fixed as well as floating point decoders are
enabled, this saves 160KiB from the bss segment for a normal build
(translating into 160KiB less memory usage if both a shared as well as
a floating point decoder have actually been used) and 160KiB from the
binary for a build with hardcoded tables.

It also means that the code to create said LUTs is no longer duplicated
(for a normal build).

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
2020-12-08 17:51:47 +01:00
Andreas Rheinhardt
ed33bbe678 avcodec/mpegaudiodec: Hardcode tables to save space
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 of 128B
each and the code to initialize them occupies 149 (fixed point) resp.
140 (floating point) bytes. So hardcode them, too.

To make the origin of the tables clear, references to the code used to
create them have been added.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
2020-12-08 17:51:47 +01:00
Andreas Rheinhardt
73bc26acb8 avcodec/mpegaudiodec: Share fixed and floating point data and init code
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
2020-12-08 17:51:47 +01:00