559319 - [HTML5] Can we avoid calling CanExecuteScripts during every fragment parsing?

Status: RESOLVED FIXED

(Core :: DOM: HTML Parser, defect, P3)

Description

[Olli Pettay [:smaug][[e-mail]]]

Fragment parsing is used for example when .innerHTML is set.
Of SetInnerHTML call CanExecuteScripts takes almost 6% when the parsed string
is just simple text.

Bug 517375 is similar bug for event handling.

Perhaps the best would be to make CanExecuteScripts fast, if possible.

Comment 1

[Boris Zbarsky [:bzbarsky]]

If we reduce the number of insane ways script can be disabled, then yes...

Comment 2

[Henri Sivonen (:hsivonen)]

In most cases currently, we could optimize by making the fragment algorithm always assume scripts are enabled. However, with the iframe sandboxing features, I think scripts in Web content can set innerHTML on a document that itself has scripting disabled.

OTOH, I'm not sure how much value is provided by supporting fragment parsing with the scripting disabled behavior as opposed to making fragment parsing always run the parsing algorithm in the scripting enabled mode. The scripts don't run anyway. It's only about how <noscript> gets treated.

Comment 3

[Boris Zbarsky [:bzbarsky]]

> However, with the iframe sandboxing features

Or with designmode, with chrome, etc.

> It's only about how <noscript> gets treated.

I would be interested in a spec change to fragment parsing, if current spec requires something interesting for <noscript>....

Comment 4

[Henri Sivonen (:hsivonen)]

This was fixed sometime before January 20 2012.