This is a reland of d76064df4f
Original change's description:
> cppgc: Rework GC info creation
>
> Previously, GCInfoTrait relied on the non-trivial constructor of a
> static object for registering a new GCInfo object. The generated code
> is required to be thread-safe which is achieved by introducing guard
> variables in the compiler.
>
> The new version is similar to Blink in that it relies on zero
> initialization of a trivially constructible atomic.
>
> Compared to guard variables that are created per GCInfo registration,
> the atomic creates less bloat (~20bytes/type) and also results in a
> better fast path.
>
> Minimum example: https://godbolt.org/z/qrdTf8
>
> Bug: chromium:1056170
> Change-Id: I95efbbf035b655d0440c9477f5391e310e2b71fa
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2764750
> Reviewed-by: Omer Katz <omerkatz@chromium.org>
> Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#73463}
Bug: chromium:1056170
Change-Id: I01e60beabc1d279d352361657f408f113aac768e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2767021
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Auto-Submit: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73471}
a03a868e39