855901 - PJS: Improve bailout logic

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Comment 1

[Shu-yu Guo [:shu]]

Attachment: patch

Removes the tracking of the 'innermost' invalidated script in parallel execution in favor of tracking the callgraph for scripts compiled for parallel execution. This allows for less wonky checking. In the old scheme, we had the following problem:

15:21 < shu> what's happening in nbody is that we have
15:21 < shu> A -> B -> C
15:21 < shu> C causes an invalidation, but gets marked on A, because we can't exactly save C onto B's IonScript inside generated ion code
15:22 < shu> but independently, A also gets invalidated, and the note that says we need to recompile C gets lost
15:22 < shu> so we recompile A, but B's already compiled, so we never see that also need to recompile C since there's no note on B
15:22 < shu> we run a while until we hit an uncompiled script

Comment 2

[David Anderson [:dvander] - inactive, e-mail if emergency]

Comment on attachment 731405 [details] [diff] [review]
patch

Review of attachment 731405 [details] [diff] [review]:
-----------------------------------------------------------------

::: js/src/ion/IonCode.h
@@ +280,5 @@
>      JSScript **scriptList() const {
>          return (JSScript **) &bottomBuffer()[scriptList_];
>      }
> +    JSScript **callTargetList() {
> +        return (JSScript **) &bottomBuffer()[callTargetList_];

For completeness, this list should be traced in IonScript::trace().

Comment 3

[Shu-yu Guo [:shu]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/0f1c94c46028

try: https://tbpl.mozilla.org/?tree=Try&rev=7fc6d979bc2c

Comment 4

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/0f1c94c46028