On 2014-02-13 17:22:50 +0100, Janne Grunau wrote:
> Altivec can only load naturally aligned vectors. To handle possibly
> unaligned data a second vector is loaded from an offset of the original
> location and the data is recovered through a vector permutation.
> Overreads are minimal if the offset for second load points to the last
> element of data. This is 7 for loading eight 8-bit pixels and overreads
> are reduced from 16 bytes to 8 bytes if the pixels are 64-bit aligned.
> For unaligned pixels the overread is reduced from 23 bytes to 15 bytes
> in the worst case.
> ---
> passes fate on both orcale ppc/ppc64 configs
> https://oracle.libav.org/powerpc-darwin9-gcc-4.2-oracle/20140213152557
> https://oracle.libav.org/powerpc64-darwin9-gcc-4.2-oracle/20140213154255
> 
>  libavcodec/ppc/dsputil_altivec.c | 20 ++++++++++----------
>  1 file changed, 10 insertions(+), 10 deletions(-)

ok-ed by Kostya on irc, will push later

Janne
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