On 2016-11-28 11:26:01 +0200, Martin Storsjö wrote: > This work is sponsored by, and copyright, Google. > > Previously all subpartitions except the eob=1 (DC) case ran with > the same runtime: > > vp9_inv_dct_dct_16x16_sub16_add_neon: 3188.1 2435.4 2499.0 1969.0 > vp9_inv_dct_dct_32x32_sub32_add_neon: 18531.7 16582.3 14207.6 12000.3 > > By skipping individual 4x16 or 4x32 pixel slices in the first pass, > we reduce the runtime of these functions like this: > > vp9_inv_dct_dct_16x16_sub1_add_neon: 274.6 189.5 211.7 235.8 > vp9_inv_dct_dct_16x16_sub2_add_neon: 2064.0 1534.8 1719.4 1248.7 > vp9_inv_dct_dct_16x16_sub4_add_neon: 2135.0 1477.2 1736.3 1249.5 > vp9_inv_dct_dct_16x16_sub8_add_neon: 2446.7 1828.7 1993.6 1494.7 > vp9_inv_dct_dct_16x16_sub12_add_neon: 2832.4 2118.3 2266.5 1735.1 > vp9_inv_dct_dct_16x16_sub16_add_neon: 3211.7 2475.3 2523.5 1983.1 > vp9_inv_dct_dct_32x32_sub1_add_neon: 756.2 456.7 862.0 553.9 > vp9_inv_dct_dct_32x32_sub2_add_neon: 10682.2 8190.4 8539.2 6762.5 > vp9_inv_dct_dct_32x32_sub4_add_neon: 10813.5 8014.9 8518.3 6762.8 > vp9_inv_dct_dct_32x32_sub8_add_neon: 11859.6 9313.0 9347.4 7514.5 > vp9_inv_dct_dct_32x32_sub12_add_neon: 12946.6 10752.4 10192.2 8280.2 > vp9_inv_dct_dct_32x32_sub16_add_neon: 14074.6 11946.5 11001.4 9008.6 > vp9_inv_dct_dct_32x32_sub20_add_neon: 15269.9 13662.7 11816.1 9762.6 > vp9_inv_dct_dct_32x32_sub24_add_neon: 16327.9 14940.1 12626.7 10516.0 > vp9_inv_dct_dct_32x32_sub28_add_neon: 17462.7 15776.1 13446.2 11264.7 > vp9_inv_dct_dct_32x32_sub32_add_neon: 18575.5 17157.0 14249.3 12015.1 > > I.e. in general a very minor overhead for the full subpartition case due > to the additional loads and cmps, but a significant speedup for the cases > when we only need to process a small part of the actual input data. > > In common VP9 content in a few inspected clips, 70-90% of the non-dc-only > 16x16 and 32x32 IDCTs only have nonzero coefficients in the upper left > 8x8 or 16x16 subpartitions respectively. > --- > Updated with Janne's suggestions. The weird speedup for > vp9_inv_dct_dct_16x16_sub16_add_neon on the Cortex A8 in the previous > iteration of the patch seems to be mostly within noise for that test; it > does still appear occasionally when testing. > --- > libavcodec/arm/vp9itxfm_neon.S | 75 > +++++++++++++++++++++++++++++++++++++----- > tests/checkasm/vp9dsp.c | 6 ++-- > 2 files changed, 70 insertions(+), 11 deletions(-)
ok Janne _______________________________________________ libav-devel mailing list libav-devel@libav.org https://lists.libav.org/mailman/listinfo/libav-devel
