The DFG speculative JIT's path for emitting an ArithMod does a divide-by-zero check on a potentially boxed integer by testing the full 64 bit value for zero. This will always succeed if the value is boxed.
Created attachment 104270 [details] the patch
<rdar://problem/9972530>
Comment on attachment 104270 [details] the patch Clearing flags on attachment: 104270 Committed r93298: <http://trac.webkit.org/changeset/93298>
All reviewed patches have been landed. Closing bug.