Add a empty mock "soundtouch_config.h" file and remove "CMAKE" compiler
definition that was used in #ifdef that skipped including
"soundtouch_config.h" in cmake build.
This is to avoid errors about missing include file when not using
autotools build.
Also update version to 2.3.1
Signed-off-by: Olli <oparviai'at'iki.fi>
Change default setting so that SIMD does not skip of unaligned memory
offsets, as that likely is not a necessary compromise with concurrent
CPUs any more.
Refactored FIRfilter and TDStretch hot-spot routines to help compiler
perform more efficient autovectorization.
Benchmarked:
- 2x/3x improvement in gcc-generated x86 SIMD code execution
times for SSE2/AVX instruction extensions accordingly, when
hand-tuned SSE intrinsics were disabled. Hand-tuned SSE code
still is slightly faster than gcc-produced AVX.
- 2.4x improvement for cumulative ARM NEON tunings when compared to
previous SoundTouch release.
Signed-off-by: Olli Parviainen <oparviai'at'iki.fi>
