Change #264963

Comments

avutil/aarch64: add pixelutils 32x32 SAD NEON implementation
This adds a NEON-optimized function for computing 32x32 Sum of Absolute
Differences (SAD) on AArch64, addressing a gap where x86 had SSE2/AVX2
implementations but AArch64 lacked equivalent coverage.

The implementation mirrors the existing sad8 and sad16 NEON functions,
employing a 4-row unrolled loop with UABAL and UABAL2 instructions for
efficient load-compute interleaving, and four 8x16-bit accumulators to
handle the wider 32-byte rows.

Benchmarks on AWS Graviton3 (Neoverse V1, c7g.xlarge) using checkasm:
  sad_32x32_0: C 146.4 cycles -> NEON  98.1 cycles (1.49x speedup)
  sad_32x32_1: C 141.4 cycles -> NEON  98.9 cycles (1.43x speedup)
  sad_32x32_2: C 140.7 cycles -> NEON  95.0 cycles (1.48x speedup)

Signed-off-by: Jeongkeun Kim <variety0724@gmail.com>

Changed files

• libavutil/aarch64/pixelutils.h
• libavutil/aarch64/pixelutils_neon.S