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[v18.x] backport various patches of internal refactorings for snapshot and realms

Rodrigo Muino Tomonari requested to merge github/fork/joyeecheung/backport-18-patches into v18.x-staging

This backports various refactoring patches for snapshot and shadow realms support to smooth out the backports of other patches. AFAICT only the shadow realms support patch changes the behavior a bit (but only if users uses the --experimental-shadow-realms flag and we don't have any compatibility guarantee for that anyway).

src: add initial shadow realm support

Add initial shadow realm support behind an off-by-default flag --experimental-shadow-realm.

PR-URL: https://github.com/nodejs/node/pull/42869 Refs: https://github.com/nodejs/node/issues/42528 Reviewed-By: Antoine du Hamel duhamelantoine1995@gmail.com Reviewed-By: Darshan Sen raisinten@gmail.com

src: per-environment time origin value

According to https://html.spec.whatwg.org/#environment-settings-object, the timeOrigin is a per-environment value. Worker's timeOrigin is the time when the worker is created.

PR-URL: https://github.com/nodejs/node/pull/43781 Reviewed-By: Matteo Collina matteo.collina@gmail.com Reviewed-By: Anna Henningsen anna@addaleax.net Reviewed-By: Paolo Insogna paolo@cowtech.it Reviewed-By: Joyee Cheung joyeec9h3@gmail.com

src: fix cppgc incompatibility in v8

This patch updates the layout of the BaseObjects to make sure that the first embedder field of them is a "type" pointer, the first 16 bits of which are the Node.js embedder ID, so that cppgc will always skip over them. In addition we now use this field to determine if the native object should be interpreted as a Node.js embedder object in the serialization and deserialization callbacks for the startup snapshot to improve the reliability.

Co-authored-by: Joyee Cheung joyeec9h3@gmail.com PR-URL: https://github.com/nodejs/node/pull/43521 Reviewed-By: James M Snell jasnell@gmail.com Reviewed-By: Darshan Sen raisinten@gmail.com

bootstrap: check more metadata when loading the snapshot

This patch stores the metadata about the Node.js binary into the SnapshotData and adds fields denoting how the snapshot was generated, on what platform it was generated as well as the V8 cached data version flag. Instead of simply crashing when the metadata doesn't match, Node.js now prints an error message and exit with 1 for the customized snapshot, or ignore the snapshot and start from scratch if it's the default one.

PR-URL: https://github.com/nodejs/node/pull/44132 Reviewed-By: Anna Henningsen anna@addaleax.net Reviewed-By: Chengzhong Wu legendecas@gmail.com

src: iterate over base objects to prepare for snapshot

Instead of iterating over the bindings, iterate over the base objects that are snapshottable. This allows us to snapshot base objects that are not bindings. In addition this refactors the InternalFieldInfo class to eliminate potential undefined behaviors, and renames it to InternalFieldInfoBase. The {de}serialize callbacks now expect a InternalFieldInfo struct nested in Snapshotable classes that can be used to carry serialization data around. This allows us to create structs inheriting from InternalFieldInfo for Snapshotable objects that need custom fields.

PR-URL: https://github.com/nodejs/node/pull/44192 Refs: https://github.com/nodejs/node/issues/37476 Reviewed-By: Anna Henningsen anna@addaleax.net Reviewed-By: Chengzhong Wu legendecas@gmail.com

src: support WeakReference in snapshot

Move util::WeakReference to a separate header and implement {de}serialization for it to be snapshotable.

PR-URL: https://github.com/nodejs/node/pull/44193 Refs: https://github.com/nodejs/node/issues/44014 Refs: https://github.com/nodejs/node/issues/37476 Reviewed-By: Matteo Collina matteo.collina@gmail.com Reviewed-By: Chengzhong Wu legendecas@gmail.com

src: introduce node::Realm

To distinguish per-context values from the node::Environment, split those values to a new node::Realm structure and consolidate bootstrapping methods with it.

PR-URL: https://github.com/nodejs/node/pull/44179 Refs: https://github.com/nodejs/node/issues/42528 Reviewed-By: Joyee Cheung joyeec9h3@gmail.com Reviewed-By: James M Snell jasnell@gmail.com

src: create BaseObject with node::Realm

BaseObject is a wrapper around JS objects. These objects should be created in a node::Realm and destroyed when their associated realm is cleaning up.

PR-URL: https://github.com/nodejs/node/pull/44348 Refs: https://github.com/nodejs/node/issues/42528 Reviewed-By: Joyee Cheung joyeec9h3@gmail.com

src: refactor BaseObject methods

  • Wrap the initialization of the kSlot and kEmbedderType fields into a BaseObject::SetInternalFields() method.
  • Move the tagging of kEmbedderType field into BaseObject::TagNodeObject()
  • Add a variant of BaseObject::MakeLazilyInitializedJSTemplate() that only needs IsolateData. This makes it easier to create BaseObject subclasses.

PR-URL: https://github.com/nodejs/node/pull/44796 Reviewed-By: Chengzhong Wu legendecas@gmail.com Reviewed-By: James M Snell jasnell@gmail.com

benchmark: add vm context global proxy benchmark

PR-URL: https://github.com/nodejs/node/pull/44796 Reviewed-By: Chengzhong Wu legendecas@gmail.com Reviewed-By: James M Snell jasnell@gmail.com

vm: make ContextifyContext a BaseObject

Instead of adding a reference to the ContextifyContext by using a v8::External, we make ContextifyContext a weak BaseObject that whose wrapper is referenced by the sandbox via a private symbol. This makes it easier to snapshot the contexts, in addition to reusing the BaseObject lifetime management for ContextifyContexts.

PR-URL: https://github.com/nodejs/node/pull/44796 Reviewed-By: Chengzhong Wu legendecas@gmail.com Reviewed-By: James M Snell jasnell@gmail.com

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