commit 954187bb1b87654226282ee3f12bda08e386c9b3
author Joyee Cheung <joyee@igalia.com> Tue Apr 22 17:31:20 2025
committer V8 LUCI CQ <v8-scoped@luci-project-accounts.iam.gserviceaccount.com> Thu Apr 24 12:22:43 2025
tree a9f96495aef7e7e43c55e33cd42212dfd75495a4
parent 8196c79e5178e93602d99255db71dbdea9abc3cf

[api] add Isolate::Deinitialize() and Isolate::Free()

This allows embedders to mirror the isolate disposal routine
with an initialization routine that uses Isolate::Allocate().

```
v8::Isolate* isolate = v8::Isolate::Allocate();
// Use the isolate address as a key.
v8::Isolate::Initialize(isolate, params);

isolate->Deinitialize();
// Remove the entry keyed by isolate address.
v8::Isolate::Free(isolate);
```

Previously, the only way to dispose the isolate bundles the
de-initialization and the freeing of the address together in
v8::Isolate::Dispose(). This is inadequate for embedders like
Node.js that uses the isolate address as a key to manage the
task runner associated with it, if another thread gets an
isolate allocated at the aligned address before the other
thread finishes cleanup for the isolate previously allocated
at the same address, and locking on the entire disposal can
be too risky since it may post GC tasks that in turn requires
using the isolate address to locate the task runner. It's a
lot simpler to handle the issue if the disposal process of
the isolate can mirror the initialization of it and split
into two routines.

Refs: https://github.com/nodejs/node/pull/57753#issuecomment-2818999420
Refs: https://github.com/nodejs/node/issues/30850
Bug: 412943769
Change-Id: I3865c27395aded3a6f32de74d96d0698b2d891b9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/6480071
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Joyee Cheung <joyee@igalia.com>
Cr-Commit-Position: refs/heads/main@{#99890}