diff options
| author | Krzysztof Pyrkosz <ffmpeg@szaka.eu> | 2025-02-28 22:21:50 +0100 |
|---|---|---|
| committer | Martin Storsjö <martin@martin.st> | 2025-03-02 01:17:53 +0200 |
| commit | e8d4c559871ef93fc94a8efb8144f1738eba4c62 (patch) | |
| tree | 5825c03dfa1a205177ceb5a8508924738758b5b7 | |
| parent | 38929b824bcc4b3307af3e0711c5c03b823a83e3 (diff) | |
| download | ffmpeg-e8d4c559871ef93fc94a8efb8144f1738eba4c62.tar.gz | |
avcodec/aarch64/ac3dsp_neon.S: Optimize ac3_sum_square_butterfly_int32_neon
Instead of calculating a^2, b^2, (a+b)^2 and (a-b)^2, calculate only
a^2, b^2 and 2*a*b in each iteration and derive the latter parts from
these three at the end.
Before and after:
A78
ac3_sum_square_bufferfly_int32_neon: 484.8 ( 2.00x)
ac3_sum_square_bufferfly_int32_neon: 468.2 ( 2.08x)
A72
ac3_sum_square_bufferfly_int32_neon: 793.6 ( 1.26x)
ac3_sum_square_bufferfly_int32_neon: 527.3 ( 1.92x)
Signed-off-by: Martin Storsjö <martin@martin.st>
| -rw-r--r-- | libavcodec/aarch64/ac3dsp_neon.S | 15 |
1 files changed, 7 insertions, 8 deletions
diff --git a/libavcodec/aarch64/ac3dsp_neon.S b/libavcodec/aarch64/ac3dsp_neon.S index 7e97cc39f7..c28e2082a9 100644 --- a/libavcodec/aarch64/ac3dsp_neon.S +++ b/libavcodec/aarch64/ac3dsp_neon.S @@ -69,21 +69,20 @@ function ff_ac3_sum_square_butterfly_int32_neon, export=1 movi v0.2d, #0 movi v1.2d, #0 movi v2.2d, #0 - movi v3.2d, #0 1: ld1 {v4.2s}, [x1], #8 ld1 {v5.2s}, [x2], #8 - add v6.2s, v4.2s, v5.2s - sub v7.2s, v4.2s, v5.2s - smlal v0.2d, v4.2s, v4.2s - smlal v1.2d, v5.2s, v5.2s - smlal v2.2d, v6.2s, v6.2s - smlal v3.2d, v7.2s, v7.2s subs w3, w3, #2 + smlal v0.2d, v4.2s, v4.2s // sum of a^2 + smlal v1.2d, v5.2s, v5.2s // sum of b^2 + sqdmlal v2.2d, v4.2s, v5.2s // sum of 2ab b.gt 1b addp d0, v0.2d addp d1, v1.2d addp d2, v2.2d - addp d3, v3.2d + sub d3, d0, d2 // a^2 + b^2 - 2ab + add d2, d0, d2 + add d3, d3, d1 // a^2 + b^2 + 2ab + add d2, d2, d1 st1 {v0.1d-v3.1d}, [x0] ret endfunc |