510673 - Add a quickstub for document.write

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, defect)

Description

[Peter Van der Beken [:peterv]]

Attachment: v1

document.write can take any number of arguments, we currently handle that in nsHTMLDocument itself but we can do it in a quickstub instead. This speeds up 2 iBench JS testcases (download_table.html and gen_page.html) by about 10%.

The quickstub string converters can already deal with JSVAL_NULL, and in that case they don't need a pointer to a jsval to root something. So instead of passing in just a |jsval*|, we can pass a |jsval| and a |jsval*|, and if the first is JSVAL_NULL we can allow NULL for the second. This change makes quickstubs possible for methods with optional string arguments. I also made it possible for a quickstub with custom code to fail (we still try to call the regular DOM method and compare the result on failure, I think that's fine).

This changes a frozen interface (nsIDOMHTMLDocument), but the change should be binary compatible and shouldn't need an IID change.

Comment 1

[Johnny Stenback (:jst)]

Comment on attachment 394651 [details] [diff] [review]
v1

Looks good!

Comment 2

[Boris Zbarsky [:bzbarsky]]

This actually changed the behavior of document.write(null) (from writing "null" to writing ""). I guess we should push forward with bug 478251 to fix that...  And perhaps add some tests for write(null) and write(undefined)?