903655 - PJS: jsop_getelem needs to always insert a barrier

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Shu-yu Guo [:shu]]

Due to not being able to call Monitor in parallel, all property reads that go through ICs in parallel need a type barrier.

Comment 1

[Shu-yu Guo [:shu]]

Attachment: bug903655-monitor-getelem.patch

Comment 2

[Brian Hackett [Laid off!]]

Comment on attachment 788430 [details] [diff] [review]
bug903655-monitor-getelem.patch

Review of attachment 788430 [details] [diff] [review]:
-----------------------------------------------------------------

::: js/src/ion/IonBuilder.cpp
@@ +8027,5 @@
>  
>      // GetPropertyParIC cannot safely call TypeScript::Monitor to ensure that
>      // the observed type set contains undefined. To account for possible
>      // missing properties, which property types do not track, we must always
>      // insert a type barrier.

I think this comment should go in needsToMonitorMissingProperties, then you don't need any notes here or in the jsop_getelem test.

Comment 3

[Shu-yu Guo [:shu]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/8d7caae654ff

Comment 4

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/8d7caae654ff