977308 - Pre-tenure frontend and XDR objects

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Terrence Cole [:terrence]]

Anything we allocate in the frontend is going to get held live on the tenured script, so is going to survive a minor GC. We should be able to just switch all of the allocation in the frontend to pre-tenure and assert in JSScript::getObject that all of the attached objects are always tenured.

Comment 1

[Terrence Cole [:terrence]]

Attachment: pre_tenure_frontend-v0.diff

This asserts that all of the script->object references are tenured->tenured (in multiple places), and fixes the one place in the frontend where we appear to be able to create a nursery object. At least the following Try run is entirely green: https://treeherder.mozilla.org/#/jobs?repo=try&revision=3a7d0415c9ca

Comment 2

[Terrence Cole [:terrence]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=3a7d0415c9ca
https://hg.mozilla.org/integration/mozilla-inbound/rev/c578789c192e

Comment 3

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/c578789c192e