Personally, I'd like to drop the patch for several reasons: It is adding a
considerable amount of complexity for very restricted use cases, and I
really don't like having just another "MathFloorOfDiv"-like mess in our
code base. Furthermore, the initial problem of undoing alpha
pre-multiplication can easily be done in a much more efficient way by using
a small (64kB) precomputed 2D table mapping a (color, alpha) pair to a
color. Tables are your best friends in any kind of signal processing. :-)

The real underlying problem is that our general representation inference
algorithm is not very clever (a.k.a. naive), and it is currently
particularly bad for division (well, it's basically wrong there). Jakob has
already done some work in this area, and we should probably wait until his
stuff landed.

Note that I am not saying that we should not improve our code generation
for e.g. floor-of-div or the division in your image processing code, it
just doesn't feel right to pile nearly unmaintainable hacks for special
cases onto each other. If we do things right, we should be able to do such
optimizations in a much more structured and cleaner way.

On Fri, Aug 10, 2012 at 1:50 AM, Evan Wallace <[email protected]> wrote:

> Just wanted to check up on this. Is the current decision to drop the patch?

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