729920 - IonMonkey: Increase maximum inlining depth

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Jan de Mooij [:jandem]]

Attachment: Patch

Attached patch increases the limit from 1 to 2. We want this for v8-richards (it doesn't need inlining of polymorphic calls after all). Still a bit slower than JM+TI, I think because we need support for constructors.

Not sure what to do with recursive calls though. JM+TI and V8 seem to never inline them, but on some micro-benchmarks I tried, inlining them can be a win. So this patch restricts recursive calls to one level to avoid a small controlflow-recursive regression.

Patch does not seem to affect Kraken or Sunspider.

Comment 1

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

Comment on attachment 599976 [details] [diff] [review]
Patch

Review of attachment 599976 [details] [diff] [review]:
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How far does JM+TI inline?

Comment 2

[Jan de Mooij [:jandem]]

(In reply to David Anderson [:dvander] from comment #1)
> 
> How far does JM+TI inline?

I'm not sure, it seems to be based on the frame/stack size, but JM+TI can inline at least two levels, I noticed this when looking at v8-richards and that's why I filed this bug. Brian, do you know how many calls JM+TI usually inlines? 

http://hg.mozilla.org/projects/ionmonkey/rev/d85d37012447

Comment 3

[Brian Hackett [Laid off!]]

Yeah, I think the reserved stack space for inlining is the only limiter for depth, which could go pretty deep.  More of an oversight really, in practice I think it would be hard to get more than 2 or 3 levels deep.