This CL:
* Moves [Heap]/[SharedClassTable] from [Isolate] to [IsolateGroup], which
will make all isolates in the group use the same heap. The GC will use
the shared class table for object size information.
* Adds support for entering/leaving an isolate group as a helper thread
(e.g. via [Thread::EnterIsolateGroupAsHelper]). The current active
isolate group can be accessed via TLS `IsolateGroup::Current()` or
`Thread::isolate_group_`. When entering as a helper thread there will be
no current isolate.
* Changes the GC to use the above mechanism and ensures GC works without
a currently active isolate. The GC will use information purely available via
[IsolateGroup]. The GC will iterate all isolates within an isolate
group e.g. for scanning roots.
* Makes spawning of new isolates start in their own isolate group.
Once the isolate is fully functional it's heap will be merged into
the original isolate group
* Moves ApiState, containing persistent and weak persistent handles,
from [Isolate] to [IsolateGroup], plus adds appropriate locking.
Issue https://github.com/dart-lang/sdk/issues/36097
Change-Id: Ia8e1d8aa78750e8400864200f4825395a182c004
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/126646
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
In some workloads, the heap is mostly large pages.
Move large executable pages from the large list to the executable list. They do not require special treatment because they are large during sweeping because we never truncate an Instructions object. They still require being swept immediately because they are executable so that code protections can be flipped before resuming Dart execution.
Fix off-by-one errors in SnapshotGraph.objects and SnapshotClass.instances discovered as a result of the large page list changing from prepending to appending.
Bug: https://github.com/flutter/flutter/issues/48360
Change-Id: If6d9137fd36c9b18205493166d586b9a7cee4b1c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/130823
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Ryan Macnak