This routine takes a synchronous non-throwing main actor isolated closure
without a result. If we are dynamically on the main actor, we just run the
closure synchronously. Otherwise, we run a new task on the main actor and call
the closure on that.
This builds on top of the previous commit by using
swift_task_isCurrentExecutorWithFlags in the implementation of this function.
To backwards deploy this function on Darwin, I used some tricks from libdispatch
to validate that we are on the main queue.
This entrypoint is similar to swift_task_isCurrentExecutor except that it
provides an ABI level option flag that enables one to configure its behavior in
a backwards deployable manner via the option flag.
I used this to expose at the ABI level the ability to check the current executor
without crashing on failure, while preserving the current behavior of
swift_task_isCurrentExecutor (which crashes on failure).
I am going to use this to implement swift_task_runOnMainActor.
To determine the correct enum layout, we first count various
categories of cases. Before, we counted indirect generic cases as
"generic", but regular "generic" cases can't export spare bits.
Change this to count "indirect" cases as a separate category.
In particular, this ensures that fully-indirect enums use
spare bits from the pointers even when some or all of the cases
are generic.
Resolves rdar://133890406
The first word in a class existential is the class pointer itself.
This pointer exposes spare bits differently depending
on the platform, which becomes apparent when you try to reflect
an Optional carrying such an MPE.
Add new test cases and some logic to zero out the first
word of spare bit information only on platforms with 8-byte pointers.
It's possible that the job we enqueue holds the last strong reference to the actor. If that job runs on another thread after we enqueue it, then it's possible for `this` to be destroyed while we're still in this function. We need to use `this` after the enqueue when the priorities don't match. When it looks like that will happen, retain `this` before the enqueue to ensure it stays alive until we're done with it.
Introduce a defensive retain helper class that makes it easy to do a single retain under certain conditions even in a loop, and does RAII to balance it with a release when the scope exits.
rdar://135400933
without relying on spare bit information in the reflection metadata
(which was added in #40906). As a result, we can remove the
code from #40906.
This is the first step in such removal. It removes the RemoteMirror
code for looking up such metadata. It leaves behind:
* Sufficient stubs for LLDB to continue to build. Once LLDB is updated, these stubs can be removed as well.
* The compiler code to emit such metadata. This allows new binaries to still reflect MPEs on older runtimes. This will need to be kept for a transitional period.
(cherry picked from commit c20ef6de2a)
Class existentials expose spare bits from all of the pointers, not just the first one.
Due to a bad bug here, we were properly exposing spare bits from the first pointer,
but then claiming that all bits of subsequent pointers were spare.
This accidentally resulted in the correct operation on 64-bit targets
(it picked the highest-order spare bit, which happened to be spare
in both the broken mask and the correct mask). But on 32-bit targets,
this exposed the high-order bits of pointers, which is incorrect.
Expand the test a bit while we're here as well.
Resolves rdar://132715829
This adds a pair of Swift protocols that represents C++ iterator types conforming to `std::contiguous_iterator_tag` requirements. These are random access iterators that guarantee that the values are stored in consequent memory addresses.
This will be used to optimize usage of C++ containers such as `std::vector` from Swift, for instance, by providing an overload of `withContiguousStorageIfAvailable` for contiguous containers.
rdar://137877849
The `CollectionDifference` type has a few different invariants
that were not being validated when initializing using the type's
`Decodable` conformance, since the type was using the
autogenerated `Codable` implementation. This change provides
manual implementations of the `Encodable` and `Decodable`
requirements, and adds tests that validate the failure when trying
to decode invalid JSON for CollectionDifference (and a few other
types).
This tends to be generally through for most `description` properties, but explicitly calling it out should help preventing people from trying to parse the result in this case.
