At the very least, we should go through s25_32 intermediate
instead of s24_32, to avoid needlessly loosing 1 LSB precision bit.
FIXME: the noise codepath is not covered with tests.
The largest integer that 32-bit floating point can exactly represent
is actually `(2^24)-1`, not`(2^23)-1` like the code assumes.
This means, whenever we use s24 as an intermediate step
to go between f32 and s32, we lose a bit of precision.
s25_32 is really a i32 with highest byte always being a sign byte.
Printing was done by adding
```
for(int e = 0; e != 13; ++e)
fprintf(stderr, "%16.32e,", ((float*)m1)[e]);
```
to `compare_mem`. I don't like how these tests work.
https://godbolt.org/z/abe94sedT
Tweak the conversion constants a bit so that they handle the
extreme ranges a bit better.
Align the C and vector instructions.
Reactivate the unit test asserts when a conversion fails.
Mark some structures, arrays static/const at various places.
In some cases this prevents unnecessary initialization
when a function is entered.
All in all, the text segments across all shared
libraries are reduced by about 2 KiB. However,
the total size increases by about 2 KiB as well.
This makes installed-tests (see commit b852b58f) do the right thing.
For build-time testing, spa/plugins/audioconvert/meson.build overrides
this with the SPA_PLUGIN_DIR environment variable, and for ad-hoc
testing by developers, pw-uninstalled.sh sets the necessary variables.
Signed-off-by: Simon McVittie <smcv@debian.org>
Pass some state to convert and channelmix functions. This makes it
possible to select per channel optimized convert functions but
also makes it possible to implement noise shaping later.
Pass the channelmix matrix and volume in the state.
Handle specialized 2 channel s16 -> f32 conversion
Improve the allocators to always align the buffer memory to the
requested alignment
Use aligned read and writes for sse functions and check alignment,
optionally falling back to unaligned path.
Add more tests and benchmark cases
Check and warn for misaligned memory in plugins.
