2 ms·

> I simply assume that all browsers do this now because we take it for granted now that JS is reasonably fast, but I could be wrong. Chrome came out a month af

by josefx 6y ago

> I simply assume that all browsers do this now because we take it for granted now that JS is reasonably fast, but I could be wrong. Chrome came out a month after Mozilla published its TraceMonkey JIT. So JITing JavaScript has been the standard thing to do since the end of 2008.

KMag 6y ago
... and TraceMonkey was based on open-sourced Macromedia/Adobe code from the ActionScript 3 VM. AS3 was loosely based on a draft of the ill-fated ES 4, but I'm not sure if it was a strict superset of an earlier ECMAScript standard. It's possible that the Flash AS3 VM had been JITing all of ES2 or ES3 earlier than TraceMonkey came out.