Patch forthcoming.
Created attachment 217143 [details] work in progress I'm marking this WIP patch r? because the only thing left is just to port it to the various assemblers. On 64-bit x86 it passes all tests.
Comment on attachment 217143 [details] work in progress Attachment 217143 [details] did not pass win-ews (win): Output: http://webkit-queues.appspot.com/results/25418007
Created attachment 217144 [details] the patch
Landed in http://trac.webkit.org/changeset/159395