Bug 199968 - [JSC] Allow GC after lowering to B3
Summary: [JSC] Allow GC after lowering to B3
Status: RESOLVED WORKSFORME
Alias: None
Product: WebKit
Classification: Unclassified
Component: JavaScriptCore (show other bugs)
Version: WebKit Nightly Build
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Yusuke Suzuki
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2019-07-19 15:36 PDT by Yusuke Suzuki
Modified: 2019-07-22 13:07 PDT (History)
1 user (show)

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Description Yusuke Suzuki 2019-07-19 15:36:05 PDT 
This is rough idea, I'm not sure whether it is already done, or it is possible.
After lowering to B3, we do not have access to JS heap. And all the cell pointers must be collected in lowering phase by `freeze`.
So, the idea is that, while optimizing things in B3, we are safe to be stopped at arbitrary time for GC.
Comment 1 Saam Barati 2019-07-22 13:07:50 PDT 
(In reply to Yusuke Suzuki from comment #0)
> This is rough idea, I'm not sure whether it is already done, or it is
> possible.
> After lowering to B3, we do not have access to JS heap. And all the cell
> pointers must be collected in lowering phase by `freeze`.
> So, the idea is that, while optimizing things in B3, we are safe to be
> stopped at arbitrary time for GC.

This is already the case. We run all of this under a safe point