1832044 - Allow weakmap lookup methods to be inlined

Status: RESOLVED FIXED

(Core :: JavaScript Engine, enhancement, P1)

Description

[Jon Coppeard (:jonco)]

Currently MovableCellHasher methods are implemented in Barrier.cpp. Apart from this WeakMap lookup methods could be totally inlined. Moving the hasher methods to a header file would allow inlining everything.

Comment 1

[Jon Coppeard (:jonco)]

Attachment: Bug 1832044 - Part 1: Rename MovableCellHasher to StableCellHasher r?sfink

Using 'stable' in the name is more descriptive. And it's quicker to say and
easier to spell.

Comment 2

[Jon Coppeard (:jonco)]

Attachment: Bug 1832044 - Part 2: Move hashing of unique IDs into the hasher r?sfink

There's no need to expose this as generic functionality.

Depends on D177525

Comment 3

[Jon Coppeard (:jonco)]

Attachment: Bug 1832044 - Part 3: Move stable hashing functionality to new header files r?sfink

This moves the unqiue ID functionality out of Zone and into the new header
files StableCellHasher.h and StableCellHasher-inl.h.

Depends on D177526

Comment 4

[Jon Coppeard (:jonco)]

Attachment: Bug 1832044 - Part 4: Move StableCellHasher method definitions to header file r?sfink

Finally we can move these methods to StableCellHasher-inl.h and allow them to
be inlined.

Local testing shows this reduces the time taken by the weakmap benchark from
49.9 to 47.4 ns, a reduction of 5%.

Depends on D177527

Comment 5

[Jon Coppeard (:jonco)]

Attachment: Bug 1832044 - Part 5: Move some parts of allocation out of line r?sfink

To counteract the effect on the instruction cache of inlining all this code we
can move some parts of allocation (which we don't expect to be as hot) out of
line.

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/b1451e959314
Part 1: Rename MovableCellHasher to StableCellHasher r=sfink
https://hg.mozilla.org/integration/autoland/rev/3797a5e30e3d
Part 2: Move hashing of unique IDs into the hasher r=sfink
https://hg.mozilla.org/integration/autoland/rev/bebf205cc1f7
Part 3: Move stable hashing functionality to new header files r=sfink
https://hg.mozilla.org/integration/autoland/rev/fa188b523ffc
Part 4: Move StableCellHasher method definitions to header file r=sfink
https://hg.mozilla.org/integration/autoland/rev/a8b602d1067a
Part 5: Move some parts of allocation out of line r=sfink
https://hg.mozilla.org/integration/autoland/rev/35d2b2ac19da
apply code formatting via Lando

Comment 7

[Noemi Erli[:noemi_erli]]

https://hg.mozilla.org/mozilla-central/rev/b1451e959314
https://hg.mozilla.org/mozilla-central/rev/3797a5e30e3d
https://hg.mozilla.org/mozilla-central/rev/bebf205cc1f7
https://hg.mozilla.org/mozilla-central/rev/fa188b523ffc
https://hg.mozilla.org/mozilla-central/rev/a8b602d1067a
https://hg.mozilla.org/mozilla-central/rev/35d2b2ac19da