Many libraries/frameworks depend on the arguments object for overloaded API entry points. This is the first step to making Arguments fast(er). We'll duplicate the logic in Arguments::create for now, and take the slow path for complicated cases like slow arguments, tearing off for strict mode, etc.
Created attachment 229745 [details]
Created attachment 229748 [details]
This is performance neutral on the benchmarks we track.
Comment on attachment 229748 [details]
View in context: https://bugs.webkit.org/attachment.cgi?id=229748&action=review
Committed r167591: <http://trac.webkit.org/changeset/167591>