1688327 - Simplify JS class-field-initializer parsing

Status: RESOLVED FIXED

(Core :: JavaScript Engine, task, P2)

Description

[Ted Campbell [:tcampbell]]

Class constructor scripts currently track the member-initializer data of the class body and save it for bytecode generation. This is currently computed when compiling the enclosing script, while we can now simply do it during initial parse.

This will be much simpler to reason about and allows moving the data to script-extra stencil section to save more memory. As well, this opens the path to allowing syntax parsing of class fields.

Comment 1

[Ted Campbell [:tcampbell]]

Attachment: Bug 1688327 - Compute ScriptStencil::memberInitializers in initial parse. r?arai!

Comment 2

[Ted Campbell [:tcampbell]]

Attachment: Bug 1688327 - Move memberInitializers to ScriptExtraStencil. r?arai!

Depends on D102822

Comment 3

[Ted Campbell [:tcampbell]]

Unsurprisingly, supporting lazy parsing as well is way more complex and out of scope.

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/6648750ced7e
Compute ScriptStencil::memberInitializers in initial parse. r=arai
https://hg.mozilla.org/integration/autoland/rev/991388ec272d
Move memberInitializers to ScriptExtraStencil. r=arai

Comment 5

[Natalia Csoregi [:nataliaCs]]

Backed out as per request (for potentially causing perf issues)

backout: https://hg.mozilla.org/integration/autoland/rev/0a991f0d6563d41838b983b3285bedbdfb8bcc89

push: https://treeherder.mozilla.org/jobs?repo=autoland&revision=991388ec272dd61462630b76f4ec86ff4de30721

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/b2385073866d
Compute ScriptStencil::memberInitializers in initial parse. r=arai
https://hg.mozilla.org/integration/autoland/rev/c9a4a9f6e6cf
Move memberInitializers to ScriptExtraStencil. r=arai

Comment 7

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/b2385073866d
https://hg.mozilla.org/mozilla-central/rev/c9a4a9f6e6cf