1674674 - Store ParserAtom HashNumber in XDR buffer

Status: RESOLVED FIXED

(Core :: JavaScript Engine, task, P1)

Description

[Ted Campbell [:tcampbell]]

In order to speed up decoding of XDR atoms data under Stencil, we can consider transcoding the HashNumber as well. With cleaned up APIs, this avoids extra lookups and hash computations.

(Note that this may be superceded by Bug 1674351..)

Comment 1

[Ted Campbell [:tcampbell]]

Attachment: Bug 1674674 - Remove ParserAtomsTable::internLatin1Seq. r?arai!

This is the same code as internChar16Seq if we chose the right
parameterization, so simplify the code a little.

Depends on D95296

Comment 2

[Ted Campbell [:tcampbell]]

Attachment: Bug 1674674 - Use HashSet::putNew when interning ParserAtom for XDR. r?arai!

We currently assert that XDR'd ParserAtoms are unique, but still use the
slightly slower lookupForAdd APIs. Instead, the patch uses putNew which
avoids an extra comparison on hash collisions.

Also greatly simplify the Char16LE case which is only used for XDR and can
safely assume no static strings or non-wide atoms are passed.

Depends on D95464

Comment 3

[Ted Campbell [:tcampbell]]

Attachment: Bug 1674674 - Transcode HashNumber for ParserAtoms. r?arai!

Include the HashNumber in XDR data so we don't need to recompute it and can
speed up interning of these known-to-be-unique ParserAtoms.

Depends on D95465

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/a330801f559c
Remove ParserAtomsTable::internLatin1Seq. r=arai
https://hg.mozilla.org/integration/autoland/rev/d2ae6815200e
Use HashSet::putNew when interning ParserAtom for XDR. r=arai
https://hg.mozilla.org/integration/autoland/rev/124f21669453
Transcode HashNumber for ParserAtoms. r=arai

Comment 5

[Dorel Luca [:dluca]]

Backed out 4 changesets (bug 1674674, bug 1674869) for build bustage in gecko/js/src/frontend/StencilXdr.cpp. CLOSED TREE

Log:
https://treeherder.mozilla.org/logviewer?job_id=320586330&repo=autoland&lineNumber=13792

Push that introduced failures:
https://treeherder.mozilla.org/jobs?repo=autoland&group_state=expanded&revision=124f2166945377d87339b99e7c468122caa76052

Backout:
https://hg.mozilla.org/integration/autoland/rev/e08cd4a3c8157686e168d48472a6fe501f3c7157

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/3c0d21f3e344
Remove ParserAtomsTable::internLatin1Seq. r=arai
https://hg.mozilla.org/integration/autoland/rev/214b47b0c334
Use HashSet::putNew when interning ParserAtom for XDR. r=arai
https://hg.mozilla.org/integration/autoland/rev/c06546640185
Transcode HashNumber for ParserAtoms. r=arai

Comment 7

[Ted Campbell [:tcampbell]]

I added an ifdef guard around the static_asserts. The has_unique_object_representations method should be available in C++17, but there is something weird in the base-toolchains-clang build.

Comment 8

[Andreea Pavel [:apavel]]

https://hg.mozilla.org/mozilla-central/rev/3c0d21f3e344
https://hg.mozilla.org/mozilla-central/rev/214b47b0c334
https://hg.mozilla.org/mozilla-central/rev/c06546640185