[Development] QML, v8 and freezing the global object

Thomas McGuire thomas.mcguire at kdab.com
Fri Oct 12 13:39:07 CEST 2012


On Thursday 11 October 2012 17:36:55 Harri Porten wrote:
> On Thu, 11 Oct 2012, Thomas McGuire wrote:
> > Could we maybe simple get rid of object freezing, and not freeze the
> > global object?
> > What would the consequences of that be, anything bad? I am the opinion
> > that if the user wants to override the "console" object, let him. Maybe
> > there were other reasons for freezing the global object though?
> My guesses for a possible difference: performance of script execution.
> Once the global object is frozen the JIT compiler can make certain
> assumptions that otherwise are not possible.

Seems that in v8, the exact opposite will happen, and property lookup is 
actually 94% slower, according to

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Thomas McGuire | thomas.mcguire at kdab.com | Software Engineer
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