According to <http://stackoverflow.com/questions/1851299/is-it-possible-to-tell-the-branch-predictor-how-likely-it-is-to-follow-the-branc>, __builtin_expect (what our LIKELY and UNLIKELY macros expand to [1]) doesn't do anything on modern CPUs. Apparently, these used to be important for PowerPC, but I don't think many folks use WebKit on PowerPC anymore.
Should we remove these macros? I wasted some time today experimenting with them without realizing that they compile to no-ops in clang. Adam [1] http://trac.webkit.org/browser/trunk/Source/WTF/wtf/Compiler.h#L188 _______________________________________________ webkit-dev mailing list [email protected] http://lists.webkit.org/mailman/listinfo/webkit-dev
