Ben Avison bavison at riscosopen.org
Wed May 27 05:16:23 PDT 2015

On Wed, 27 May 2015 12:24:58 +0100, Pekka Paalanen <ppaalanen at gmail.com> wrote:

> with summary fixed, this patch seems ok to me (it does not change the
> content), but it does reorder the rows. I would assume the relative
> ordering change in this case does not matter, but can someone confirm
> that?

Yes, there is some reordering, but the only significant thing to ensure
that the same routine is chosen is that a COVER fast path for a given
combination of operator and source/destination pixel formats must precede
all the variants of repeated fast paths for the same combination. This
patch (and the other mmx/sse2 one) still follows that rule.

I believe that in every other case, the set of operations that match any
pair of fast paths that are reordered in these patches are mutually
exclusive. While there will be a very subtle timing difference due to the
distance through the table we have to search to find a match (sometimes
faster, sometime slower) there is no evidence that the tables have been
carefully ordered by frequency of occurrence - just for ease of copy-and-


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