1682315 - Consider splitting SourceExtent from ScriptStencil

Status: RESOLVED FIXED

(Core :: JavaScript Engine, task, P1)

Description

[Ted Campbell [:tcampbell]]

Now that the SourceExtent is const for a js::BaseScript, its final value is known during initial parse and the delazification process no longer needs to generate it. This also simplifies what goes in the incremental stencil XDR data.

Comment 1

[Ted Campbell [:tcampbell]]

Attachment: Bug 1682315 - Split the SourceExtent from ScriptStencil. r?arai!

Store the SourceExtents of a stencil outside the ScriptStencil and instead in
a parallel vector. Subsequent patches will then only generate this for the
initial stencil and not for any delazification stencils. This is possible
since SourceExtent is immutable (and has expected value) after initial parse.

Comment 2

[Ted Campbell [:tcampbell]]

Attachment: Bug 1682315 - Don't generate Stencil SourceExtent for delazification. r?arai!

Since the SourceExtent is duplicate data in delazifications, we can avoid
filling in that vector entirely.

Depends on D99683

Comment 3

[Ted Campbell [:tcampbell]]

Attachment: Bug 1682315 - Add CompilationStencil::functionKey. r?arai!

Add this field once per CompilationStencil (eg. the initial compile and each
delazification). Later this will allow us avoid generating SourceExtents
altogether while delazifying.

Depends on D99683

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/a53d27a539a9
Split the SourceExtent from ScriptStencil. r=arai
https://hg.mozilla.org/integration/autoland/rev/68b34f80063c
Add CompilationStencil::functionKey. r=arai
https://hg.mozilla.org/integration/autoland/rev/8cb6581e6784
Don't generate Stencil SourceExtent for delazification. r=arai

Comment 5

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/a53d27a539a9
https://hg.mozilla.org/mozilla-central/rev/68b34f80063c
https://hg.mozilla.org/mozilla-central/rev/8cb6581e6784