1694054 - Add CompilationStencil::unshare

Status: RESOLVED WONTFIX

(Core :: JavaScript Engine, task, P3)

Description

[Tooru Fujisawa [:arai]]

CompilationStencil decoded from XDR buffer has pointer to the XDR buffer,
and if the XDR buffer has shorter lifetime than CompilationStencil,
CompilationStencil needs to copy all data out of XDR buffer.

Comment 1

[Tooru Fujisawa [:arai]]

Attachment: Bug 1694054 - Add CompilationStencil::unshare and JS::UnshareStencil. r?tcampbell!

Depends on D105157

Comment 2

[Tooru Fujisawa [:arai]]

To be clear, currently there's no consumer of unshare in the patch stack.
it's possibly for ScriptPreloader/StartupCache usage, or later phase

Comment 3

[Tooru Fujisawa [:arai]]

maybe it's better adding public API and also jsapi-test

Comment 4

[Tooru Fujisawa [:arai]]

for XDR decode case, bug 1731629 will provide CompileOptions.borrowBuffer that allows not borrowing the buffer when decoding,
so that there's no need to unshare on the stencil.

Comment 5

[Tooru Fujisawa [:arai]]

so far we don't need unshare method.
we have multiple similar methods for different purposes, such as steal, cloneFrom