tree eaf9d02b921cbd553c5cdc61059bac88f7c76160
parent 67e5e79dbe6745bf2b0c25c1a56acf97e2b8966a
author George Steed <george.steed@arm.com> 1712936694 +0100
committer Frank Barchard <fbarchard@chromium.org> 1714592803 +0000

[AArch64] Add SVE2 implementations for ARGBToUVRow and similar

By maintaining the interleaved format of the data we can use a common
kernel for all input channel orderings and simply pass a different
vector of constants instead.

A similar approach is possible with only Neon by making use of
multiplies and repeated application of ADDP to combine channels, however
this is slower on older cores like Cortex-A53 so is not pursued further.

For odd problem sizes we need a slightly different implementation for
the final element, so introduce an "any" kernel to address that rather
than bloating the code for the common case.

Observed affect on runtimes compared to the existing Neon kernels:

             | Cortex-A510 | Cortex-A720 | Cortex-X2
ABGRToUVJRow |      -15.5% |       +5.4% |    -33.1%
 ABGRToUVRow |      -15.6% |       +5.3% |    -35.9%
ARGBToUVJRow |      -10.1% |       +5.4% |    -32.7%
 ARGBToUVRow |      -10.1% |       +5.4% |    -29.3%
 BGRAToUVRow |      -15.5% |       +4.6% |    -32.8%
 RGBAToUVRow |      -10.1% |       +4.2% |    -36.0%

Bug: libyuv:973
Change-Id: I041ca44db0ae8a2adffcdf24e822eebe962baf33
Reviewed-on: https://chromium-review.googlesource.com/c/libyuv/libyuv/+/5505537
Reviewed-by: Frank Barchard <fbarchard@chromium.org>
Commit-Queue: Frank Barchard <fbarchard@chromium.org>