795896 - UnwrapProxy is slow

Status: RESOLVED FIXED

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

Description

[Boris Zbarsky [:bzbarsky]]

In particular, it does xpc::WrapperFactory::IsXrayWrapper, which actually goes and does UnwrapObject (out of line, natch) and all sorts of crud like that.

And some of the places we're calling it (e.g. getElementIfPresent, get) we already asserted !IsXrayWrapper.

And some other places (finalize) we had better be able to assert it.

Peter, are there other places we can assert it too?  Presumably not getOwnPropertyDescriptor, right?  What other hooks do Xrays call?

Comment 1

[Boris Zbarsky [:bzbarsky]]

Attachment: Initial cut at making this better, doesn't cover all callsites

Comment 2

[Boris Zbarsky [:bzbarsky]]

Based on recent discussions with waldo, it sounds like I shouldn't be assuming that xrays will only call getOwnPropertyDescriptor... Which means I do need to keep doing conditional unwrap in all the hooks.  :(

I can at least make it not do random out of line calls, though.

Comment 3

[Boris Zbarsky [:bzbarsky]]

Attachment: Speed up UnwrapProxy, since we know what we have there is either an Xray or our proxy.

Comment 4

[Boris Zbarsky [:bzbarsky]]

http://hg.mozilla.org/integration/mozilla-inbound/rev/19b9f064d8eb

Comment 5

[(no longer active)]

Backed out because of build bustage:

https://hg.mozilla.org/integration/mozilla-inbound/rev/d9e8e6757121

https://tbpl.mozilla.org/?tree=Mozilla-Inbound&rev=32786d29daf8

Comment 6

[Boris Zbarsky [:bzbarsky]]

Relanded; it had nothing to do with the bustage:

https://hg.mozilla.org/integration/mozilla-inbound/rev/f68f04e1fa23

Comment 7

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/f68f04e1fa23