[FFmpeg-devel] [PATCH 5/5] aarch64/opusdsp: implement NEON accerelated postfilter and deemphasis

[Lynne]

23 Mar 2019, 16:20 by ceffmpeg at gmail.com:

> 2019-03-23 17:16 GMT+01:00, Lynne <> dev at lynne.ee <mailto:dev at lynne.ee>> >:
>
>> 23 Mar 2019, 15:04 by >> ceffmpeg at gmail.com <mailto:ceffmpeg at gmail.com>>> :
>>
>>> 2019-03-23 15:23 GMT+01:00, Lynne <> >>> dev at lynne.ee <mailto:dev at lynne.ee>>>>  <mailto:>>> dev at lynne.ee <mailto:dev at lynne.ee>>>> >>
>>> >:
>>>
>>>> 16 Mar 2019, 16:34 by >> >>>> dev at lynne.ee <mailto:dev at lynne.ee>>>>>  <mailto:>>>> dev at lynne.ee <mailto:dev at lynne.ee>>>>> >>> :
>>>>
>>>>> 153372 UNITS in postfilter_c,   65536 runs,      0 skips
>>>>> 73164 UNITS in postfilter_neon,   65536 runs,      0 skips -> 2.1x
>>>>> speedup
>>>>>
>>>>> 80591 UNITS in deemphasis_c,  131072 runs,      0 skips
>>>>> 43969 UNITS in deemphasis_neon,  131072 runs,      0 skips -> 1.83x
>>>>> speedup
>>>>>
>>>>> Total decoder speedup: ~15% on a Raspberry Pi 3 (from 28.1x to 33.5x
>>>>> realtime)
>>>>>
>>>>> Deemphasis SIMD based on the following unrolling:
>>>>> const float c1 = CELT_EMPH_COEFF, c2 = c1*c1, c3 = c2*c1, c4 = c3*c1;
>>>>> float state = coeff;
>>>>>
>>>>> for (int i = 0; i < len; i += 4) {
>>>>>  y[0] = x[0] + c1*state;
>>>>>  y[1] = x[1] + c2*state + c1*x[0];
>>>>>  y[2] = x[2] + c3*state + c1*x[1] + c2*x[0];
>>>>>  y[3] = x[3] + c4*state + c1*x[2] + c2*x[1] + c3*x[0];
>>>>>
>>>>>  state = y[3];
>>>>>  y += 4;
>>>>>  x += 4;
>>>>> }
>>>>>
>>>>> Unlike the x86 version, duplication is used instead of pslldq so
>>>>> the structure and tables are different.
>>>>> Same approach tested on x86 (3x pslldq -> vbroadcastss + shufps +
>>>>> pslldq)
>>>>> had the same performance, so 3x pslldq was kept as vbroadcastss has a
>>>>> higher latency.
>>>>>
>>>>
>>>> Could someone review the patches?
>>>>
>>>
>>> Which toolchains did you test?
>>> (For compilation, not performance.)
>>>
>>
>> gcc 8.2.1 on both aarch64 and x86-64
>>
>
> Please also test Android and tell us if you
> can test ios compilation.
> (Assuming you cannot test arm64 for Windows.)
>

I can't install aarch64 android on the raspberry pi 3 so I can't test that. I don't know if cross-compilation is even possible for aarch64 windows.
I don't have an ios device.