1090584 - 3x slower on dart2js output of DeltaBlue benchmark vs v8

Status: NEW

(Core :: JavaScript Engine, defect)

Description

[Alon Zakai (:azakai)]

Attachment: fromDart.js

Related to bug 1090583, this is another benchmark where dart2s output is much slower in spidermonkey than v8, here DeltaBlue is 3x slower.

Comment 1

[Jan de Mooij [:jandem]]

On 32-bit we're now about 2x slower than V8.

We have > 25% of time under js::array_push, because we're failing to inline some push calls. The PropertyWriteNeedsTypeBarrier call in IonBuilder::inlineArrayPush returns true.

Fixing that will hopefully close most of the gap with V8, but this will likely need more work.

Bug 1090583 comment 7 applies here as well, but fixing it isn't a big win here. Also, --unboxed-objects wins a few %. Might be more on 64-bit.