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Fix incremental GC assertion in ValidateIncrementalMarking

RESOLVED FIXED in mozilla14

Status

()

Core
JavaScript Engine
RESOLVED FIXED
5 years ago
5 years ago

People

(Reporter: billm, Assigned: billm)

Tracking

unspecified
mozilla14
Points:
---

Firefox Tracking Flags

(Not tracked)

Details

Attachments

(1 attachment)

(Assignee)

Description

5 years ago
Created attachment 614066 [details] [diff] [review]
patch

I was a little overzealous in bug 739899 when I tried to remove all full GC flags. As a consequence, the following can now happen:

1. Start an incremental GC with all compartments being collected. Therefore, the atoms compartment can be collected.
2. A new compartment is created
3. When the GC is finished, call ValidateIncrementalMarking.
4. It calls MarkRuntime again. This time, since the new compartment is not being collected, we mark all atoms.
5. ValidateIncrementalMarking asserts because the incremental GC didn't mark all the atoms, while the non-incremental one did.

This is a bogus assertion. We're not required to mark all atoms in this situation. Any atoms pointed to by the new compartment either existed before or else they were new, and we'll mark them either way.

The patch just adds a "full GC" flag that is set at the beginning of the incremental GC and used by both calls to MarkRuntime.
Attachment #614066 - Flags: review?(igor)

Updated

5 years ago
Attachment #614066 - Flags: review?(igor) → review+
(Assignee)

Comment 1

5 years ago
https://hg.mozilla.org/integration/mozilla-inbound/rev/ae32cca25ce0
Target Milestone: --- → mozilla14
https://hg.mozilla.org/mozilla-central/rev/ae32cca25ce0
Status: NEW → RESOLVED
Last Resolved: 5 years ago
Resolution: --- → FIXED
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