It's possible to speed up opcodes that use toBoolean conversion in a number of ways:
1) Make JSValue::toBoolean nonvirtual and completely inline by
making use of the StructureID type field.
2) Make JSValue::toBoolean not take an ExecState; doesn't need it.
3) Make op_not, op_loop_if_true and op_jtrue not read the
ExecState (toBoolean doesn't need it any more) and not check
exceptions (toBoolean can't throw).
Created attachment 24116 [details]
Comment on attachment 24116 [details]
r=me. Please include the perf delta in the ChangeLog.