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aarch64 : vp9 : use alternative returns in the core loop filter function
14 novembre 2016, par Janne Grunauaarch64: vp9: use alternative returns in the core loop filter function Since aarch64 has enough free general purpose registers use them to branch to the appropiate storage code. 1-2 cycles faster for the functions using loop_filter 8/16, ... on a cortex-a53. Mixed results (up to 2 cycles faster/slower) on a cortex-a57.
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libschroedingerdec : don’t produce empty frames
13 novembre 2016, par Andreas Cadhalpun -
aarch64 : vp9 : Implement NEON loop filters
13 novembre 2016, par Martin Storsjöaarch64: vp9: Implement NEON loop filters This work is sponsored by, and copyright, Google. These are ported from the ARM version; thanks to the larger amount of registers available, we can do the loop filters with 16 pixels at a time. The implementation is fully templated, with a single macro which can generate versions for both 8 and 16 pixels wide, for both 4, 8 and 16 pixels loop filters (and the 4/8 mixed versions as well). For the 8 pixel wide versions, it is pretty close in speed (the v_4_8 and v_8_8 filters are the best examples of this; the h_4_8 and h_8_8 filters seem to get some gain in the load/transpose/store part). For the 16 pixels wide ones, we get a speedup of around 1.2-1.4x compared to the 32 bit version. Examples of runtimes vs the 32 bit version, on a Cortex A53: ARM AArch64 vp9_loop_filter_h_4_8_neon: 144.0 127.2 vp9_loop_filter_h_8_8_neon: 207.0 182.5 vp9_loop_filter_h_16_8_neon: 415.0 328.7 vp9_loop_filter_h_16_16_neon: 672.0 558.6 vp9_loop_filter_mix2_h_44_16_neon: 302.0 203.5 vp9_loop_filter_mix2_h_48_16_neon: 365.0 305.2 vp9_loop_filter_mix2_h_84_16_neon: 365.0 305.2 vp9_loop_filter_mix2_h_88_16_neon: 376.0 305.2 vp9_loop_filter_mix2_v_44_16_neon: 193.2 128.2 vp9_loop_filter_mix2_v_48_16_neon: 246.7 218.4 vp9_loop_filter_mix2_v_84_16_neon: 248.0 218.5 vp9_loop_filter_mix2_v_88_16_neon: 302.0 218.2 vp9_loop_filter_v_4_8_neon: 89.0 88.7 vp9_loop_filter_v_8_8_neon: 141.0 137.7 vp9_loop_filter_v_16_8_neon: 295.0 272.7 vp9_loop_filter_v_16_16_neon: 546.0 453.7 The speedup vs C code in checkasm tests is around 2-7x, which is pretty much the same as for the 32 bit version. Even if these functions are faster than their 32 bit equivalent, the C version that we compare to also became around 1.3-1.7x faster than the C version in 32 bit. Based on START_TIMER/STOP_TIMER wrapping around a few individual functions, the speedup vs C code is around 4-5x. Examples of runtimes vs C on a Cortex A57 (for a slightly older version of the patch): A57 gcc-5.3 neon loop_filter_h_4_8_neon: 256.6 93.4 loop_filter_h_8_8_neon: 307.3 139.1 loop_filter_h_16_8_neon: 340.1 254.1 loop_filter_h_16_16_neon: 827.0 407.9 loop_filter_mix2_h_44_16_neon: 524.5 155.4 loop_filter_mix2_h_48_16_neon: 644.5 173.3 loop_filter_mix2_h_84_16_neon: 630.5 222.0 loop_filter_mix2_h_88_16_neon: 697.3 222.0 loop_filter_mix2_v_44_16_neon: 598.5 100.6 loop_filter_mix2_v_48_16_neon: 651.5 127.0 loop_filter_mix2_v_84_16_neon: 591.5 167.1 loop_filter_mix2_v_88_16_neon: 855.1 166.7 loop_filter_v_4_8_neon: 271.7 65.3 loop_filter_v_8_8_neon: 312.5 106.9 loop_filter_v_16_8_neon: 473.3 206.5 loop_filter_v_16_16_neon: 976.1 327.8 The speed-up compared to the C functions is 2.5 to 6 and the cortex-a57 is again 30-50% faster than the cortex-a53. Signed-off-by: Martin Storsjö <martin@martin.st> -
aarch64 : vp9 : Add NEON itxfm routines
13 novembre 2016, par Martin Storsjöaarch64: vp9: Add NEON itxfm routines This work is sponsored by, and copyright, Google. These are ported from the ARM version; thanks to the larger amount of registers available, we can do the 16x16 and 32x32 transforms in slices 8 pixels wide instead of 4. This gives a speedup of around 1.4x compared to the 32 bit version. The fact that aarch64 doesn't have the same d/q register aliasing makes some of the macros quite a bit simpler as well. Examples of runtimes vs the 32 bit version, on a Cortex A53: ARM AArch64 vp9_inv_adst_adst_4x4_add_neon: 90.0 87.7 vp9_inv_adst_adst_8x8_add_neon: 400.0 354.7 vp9_inv_adst_adst_16x16_add_neon: 2526.5 1827.2 vp9_inv_dct_dct_4x4_add_neon: 74.0 72.7 vp9_inv_dct_dct_8x8_add_neon: 271.0 256.7 vp9_inv_dct_dct_16x16_add_neon: 1960.7 1372.7 vp9_inv_dct_dct_32x32_add_neon: 11988.9 8088.3 vp9_inv_wht_wht_4x4_add_neon: 63.0 57.7 The speedup vs C code (2-4x) is smaller than in the 32 bit case, mostly because the C code ends up significantly faster (around 1.6x faster, with GCC 5.4) when built for aarch64. Examples of runtimes vs C on a Cortex A57 (for a slightly older version of the patch): A57 gcc-5.3 neon vp9_inv_adst_adst_4x4_add_neon: 152.2 60.0 vp9_inv_adst_adst_8x8_add_neon: 948.2 288.0 vp9_inv_adst_adst_16x16_add_neon: 4830.4 1380.5 vp9_inv_dct_dct_4x4_add_neon: 153.0 58.6 vp9_inv_dct_dct_8x8_add_neon: 789.2 180.2 vp9_inv_dct_dct_16x16_add_neon: 3639.6 917.1 vp9_inv_dct_dct_32x32_add_neon: 20462.1 4985.0 vp9_inv_wht_wht_4x4_add_neon: 91.0 49.8 The asm is around factor 3-4 faster than C on the cortex-a57 and the asm is around 30-50% faster on the a57 compared to the a53. Signed-off-by: Martin Storsjö <martin@martin.st> -
vp9 : split superframes in the filtering stage before actual decoding
13 novembre 2016, par Anton Khirnov
