Implement the fixed-point LFE x96 interpolation filter in AArch64
NEON. Four input samples are processed per iteration. The history
sample is kept in a vector lane, and ext constructs the delayed input.
Benchmarks by Martin Storsjö using checkasm:
a53 a55 a520 a72 a76 a720
1.86x 1.88x 1.24x 1.99x 1.62x 2.30x
Author's measurement on Neoverse-N1 (Oracle Cloud, clang 14): 1.29x.
Signed-off-by: Jeongkeun Kim <variety0724@gmail.com>
Jeongkeun Kim
280fd60916