Some not very technical discussion of what was involved here: http://blog.mozilla.com/dmandelin/2011/04/22/mozilla-javascript-2011/ http://blog.mozilla.com/dman

Some not very technical discussion of what was involved here: http://blog.mozilla.com/dmandelin/2011/04/22/mozilla-javascript-2011/ http://blog.mozilla.com/dmandelin/2011/04/22/mozilla-javascr... (Scroll down to the 'Type Inference' section) And somewhat more technical (although mostly about IonMonkey) here: https://bugzilla.mozilla.org/show_bug.cgi?id=650180 https://bugzilla.mozilla.org/show_bug.cgi?id=650180 -edit- Found actual 'Type Inference' bugzilla discussion: https://bugzilla.mozilla.org/show_bug.cgi?id=557407 https://bugzilla.mozilla.org/show_bug.cgi?id=557407