Created attachment 33880 [details] [review] Optimize shadowUpdatePacked(). We already ship this patch in the ARM Linux Internet Platform, and it looks like a good candidate for upstream inclusion.
Can you please send the patch for review to xorg-devel@lists.x.org?
This was fixed today by git commit f0b4df99486066ad0e638b3b5debc905bc8ef1c4.
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