[FFmpeg-devel] [PATCH] Heavy optimization of IFF decoder
Tue Apr 27 23:04:34 CEST 2010
Sebastian Vater a ?crit :
> Sebastian Vater a ?crit :
>> Michael Niedermayer a ?crit :
>>> speaking of registers
>>> for(dst; dst<end; dst+=4)
>>> would reduce the number of variables by 1
>>> const uint32_t v = AV_RN32A(dst) | lut[get_bits(&gb, 4)];
>>> AV_WN32A(dst, v);
>>> might be worth a try
>>> and make sure dst is 4 byte aligned
>> Great! It works now like a charm now for me, too.
>> I also got the 3% speedup ;)
>> Patch attached!
>> But could you try out and compare the new patch, if it doesn't cause any
>> side effects?
>> Load several 8bpp IFF files and see if something is truncated, etc.
>> I'm far too tired right now, and just falling to bed!
>> Good night and nice dreams!
> Just figured out that the (buf_size * 8) + bps - 1 expression can be
> simplified to (buf_size * 8), at least it didn't change Heart.ILBM.
> New patch attached fixing this! But that's really the very last one for
Argghh, did apply the wrong patch!
Also I noticed that it can just be reduced to (buf_size * 8) + bps
not to (buf_size * 8), so just the - 1 is discarded.
I shouldn't sent patched when extremely tired, sorry for the inconvience!
:-) Basty/CDGS (-
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