Re: more permute optimizations

[David Bateman]

Jaroslav Hajek wrote:
> Unless David (or anyone else) objects, I'll replace the transpose
> implementation by a call to the routine using pointers. I also
> tinkered with the block size a bit, but it seems to me that 8 was a
> good guess from David.
> The best block size seems to depend on the problem dimensions, and I
> bet that dependence is nontrivial.
>   

If its faster I have no objections.. The 8x8 block size arises as a 
typical cache typically has 16 independent lines, and not all are 
available available as some will be taken by your code.. Each line of 
the block takes a cache line and so 8x8 is the largest reasonable size 
before cache misses start happening within the copying of the block itself..

D.

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