[Ffmpeg-devel] [BUG] H.264 + AltiVec == heavy artefacts

Romain Dolbeau romain
Fri Oct 7 17:45:15 CEST 2005

matthieu castet wrote:

> How does PPC manage allignement stuff ?
> Is it done in cpu or in kernel ?

It doesn't, neither ; at least in AltiVec. AltiVec load ignore the lower 4 bits
of the address, and use 0 instead. It's up to the programmer to either
guarantee the alignment of the data, or to use vec_lvsl & vec_perm to
work the apropriate magic. In the case of store, dark magic is a more
accurate description :-(

Romain Dolbeau
<romain at dolbeau.org>

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