The DFG JIT bytecode parser converts equal-null compare/branch opcodes into a tree of JSConstant(null), an equality comparison, and a branch. The backend never special-cases the equal-to-null case, and treats it as a normal equality comparison; this means that equal-null always takes slow path. The DFG JIT backend should have a peephole optimization for this case.
Created attachment 101170 [details]
Comment on attachment 101170 [details]
Clearing flags on attachment: 101170
Committed r91208: <http://trac.webkit.org/changeset/91208>
All reviewed patches have been landed. Closing bug.