I had originally thought that we'd get away without this because the
executor construction generally happens in the async `main` function,
but of course if a program doesn't already use Swift Concurrency,
and someone uses it from a plug-in or library it loads, there's a
risk that we might have a race condition.
rdar://149346132
This memory is part of the conformance cache concurrent hash map, so
when we clear the conformance cache, record each of the allocated
pointers within the concurrent map's free list. This way, it'll be
freed with the rest of the concurrent map when it's safe to do so.
Add a new language feature to avoid the stdlib’s swiftinterface becoming unintelligible to outdated compiler builds due to the generalization of Builtin.is_same_metatype.
rdar://149396721
With relative witness tables, the low bit of a witness table pointer is
an indicator that we need to load from the given pointer. We were also
using the low bit of the witness table pointer in the conformance
cache entry as part of a pointer union. Hilarity ensures [*].
Switch to another low bit by exploding the conformance cache key
into separate fields and taking the low bit of one of those pointers
that isn't reserved.
Fixes the remainder of rdar://149326058, I hope.
[*] No, I am not laughing.
Previously there was still a sneaky hop which caused ordering issues.
This introduced a specific test startSynchronously_order which checks
that the task enqueues indeed are "immediate" and cleans up how we
handle this.
This also prepares for the being discussed in SE review direction of
this API that it SHOULD be ALLOWED to actually hop and NOT be
synchronous at all IF the isolation is specified on the closure and is
DIFFERENT than the callers dynamic isolation.
This effectively implements "synchronously run right now if dynamically
on the exact isolation as requested by the closure; otherwise enqueue
the task as usual".
resolves rdar://149284186
cc @drexin
Seems that during refactorings of child cancellations we somehow missed
also cancelling the group itself. It seems we did not have good test
coverage of the addTaskUnlessCancelled somehow and thus this slipped
through.
This adds a regression test for addTaskUnlessCancelled and fixes how we
handle the cancellation effect in TaskStatus.
resolves#80789
resolves rdar://149177600
Because `TaskAllocator` is not a round multiple of the machine word
size on 64-bit platforms, I think we end up with padding before the
`TaskLocal::Storage` following it, which makes the `PrivateStorage`
structure larger than the calculation in `ABI/Task.h`.
rdar://149067144
We decided that using a magic typealias to set the executor factory was better
than using a compiler option. Remove the `-executor-factory` option, and replace
by looking up the `DefaultExecutorFactory` type, first in the main module, and
then if that fails in Concurrency.
rdar://149058236
Function types aren't always trivially copyable, e.g. with address-discriminated signed pointers on ARM64e. Introduce a function_cast helper and use that instead.
