This is a follow up to https://github.com/swiftlang/swift/pull/80862, where `storeEnumTagSinglePayload` in a special implementation of `ResultTypeInfo` for Embedded Swift had a mismatching number of arguments. The actual declaration of it in `ABI/ValueWitness.def` clearly includes one more argument.
```
/// void (*storeEnumTagSinglePayload)(T* enum, UINT_TYPE whichCase,
/// UINT_TYPE emptyCases, M *self);
/// Given uninitialized memory for an instance of a single payload enum with a
/// payload of this witness table's type (e.g Optional<ThisType>), store the
/// tag.
FUNCTION_VALUE_WITNESS(storeEnumTagSinglePayload,
StoreEnumTagSinglePayload,
VOID_TYPE,
(MUTABLE_VALUE_TYPE, UINT_TYPE, UINT_TYPE, TYPE_TYPE))
```
This function type mismatch is illegal when targeting Wasm and traps at run time.
Similarly to #80862, we're passing `nullptr` as the newly added argument, which is equivalent to the existing behavior on other platforms.
rdar://157219474
This may be useful for type layout of borrow fields in the future, should we
decide that addressable-for-dependencies borrows should always be represented
by a pointer. rdar://153650278
We missed to sign the handler. Along the way the signature of it
changed, so adjust for that.
How to get the number:
```
func PROPER(bar: (TaskPriority, TaskPriority) -> Void) {
let p = TaskPriority.default
bar(p, p)
}
```
```
-> % swiftc -target arm64e-apple-macos13 example.swift -S -o - | swift demangle | grep -a3 autda
stur x8, [x29, #-64]
mov x17, x8
movk x17, #11839, lsl #48 <<<<<<<<<
autda x16, x17
ldr x8, [x16, #64]
lsr x8, x8, #0
add x8, x8, #15
```
Resolves rdar://150378890
This changes the isIsolatingCurrentContext function to return `Bool?`
and removes all the witness table trickery we did previously to detect
if it was implemented or not. This comes at a cost of trying to invoke
it always, before `checkIsolated`, but it makes for an simpler
implementation and more checkable even by third party Swift code which
may want to ask this question.
Along with the `withSerialExecutor` function, this now enables us to
check the isolation at runtime when we have an `any Actor` e.g. from
`#isolation`.
Updates SE-0471 according to
https://forums.swift.org/t/se-0471-improved-custom-serialexecutor-isolation-checking-for-concurrency-runtime/78834/
review discussions
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
To facilitate back deployment, make use of the fact that the async bit
has up to now never been set for read and modify accessors and claim
that set bit to indicate that it is a callee-allocated coroutine. This
has the virtue of being completely back deployable because like async
function pointers coro function pointers must be auth'd and signed as
data.
ActiveTaskStatusSize is 2 words, not 4, on most targets.
PrivateStorageSize is measured in bytes, not words, so the Storage field needs to be a char[].
Certain dynamic casts cannot work safely with isolated conformances,
regardless of what executor the code runs on. For such cases, reject
all attempts to conform to the type.
Move to a recursive lock inline in the Task. This avoids the need to allocate a lock record and simplifies the code somewhat.
Change Task's OpaquePrivateStorage to compute its size at build time based on the sizes of its components, rather than having it be a fixed size. It appears that the fixed size was intended to be part of the ABI, but that didn't happen and we're free to change this size. We need to expand it slightly when using pthread_mutex as the recursive lock, as pthread_mutex is pretty big. Other recursive locks allow it to shrink slightly.
We don't have a recursive mutex in our Threading support code, so add a RecursiveMutex type.
rdar://113898653
_swift_taskGroup_cancelAllChildren relies on there being no concurrent modification when called from the owning task, but this is not guaranteed.
Rearrange things to always take the owning task's status record lock when walking the group's children. Split _swift_taskGroup_cancelAllChildren into two functions, one which assumes/requires the lock is already held, and one which acquires the lock. We don't have the owning task in this case, but we can either get it from the current task, or by looking at the parent of the child task we're working on.
rdar://147172991
* [Concurrency] Detect non-default impls of isIsolatingCurrentContext
* [Concurrency] No need for trailing info about isIsolating... in conformance
* Apply changes from review
* [Concurrency] Adjust task escalation APIs to SE accepted shapes
* adjust test a little bit
* Fix closure lifetime in withTaskPriorityEscalationHandler
* avoid bringing workaround func into abi by marking AEIC
Replace the pair of global actor type/conformance we are passing around with
a general "conformance execution context" that could grow new functionality
over time. Add three external symbols to the runtime:
* swift_conformsToProtocolWithExecutionContext: a conforms-to-protocol check
that also captures the execution context that should be checked before
using the conformance for anything. The only execution context right now
is for an isolated conformance.
* swift_isInConformanceExecutionContext: checks whether the function is
being executed in the given execution context, i.e., running on the
executor for the given global actor.
* swift_ConformanceExecutionContextSize: the size of the conformance
execution context. Client code outside of the Swift runtime can allocate
a pointer-aligned region of memory of this size to use with the runtime
functions above.
In the prior implementation of runtime resolution of isolated conformances,
the runtime had to look in both the protocol conformance descriptor and
in all conditional conformance requirements (recursively) to find any
isolated conformances. If it found one, it had to demangle the global
actor type to metadata. Since swift_conformsToProtocol is a hot path through
the runtime, we can't afford this non-constant-time work in the common
case.
Instead, cache the resolved global actor and witness table as part of the
conformance cache, so that we have access to this information every time
we look up a witness table for a conformance. Propagate this up through
various callers (e.g., generic requirement checking) to the point where
we either stash it in the cache or check it at runtime. This gets us down
to a very quick check (basically, NULL-or-not) for nonisolated conformances,
and just one check for isolated conformances.
Following the approach taken with the concurrency-specific type
descriptors, register a hook function for the "is current global actor"
check used for isolated conformances.
Extend the metadata representation of protocol conformance descriptors
to include information about the global actor to which the conformance is
isolated (when there is one), as well as the conformance of that type to
the GlobalActor protocol. Emit this metadata whenever a conformance is
isolated.
When performing a conforms-to-protocol check at runtime, check whether
the conformance that was found is isolated. If so, extract the serial
executor for the global actor and check whether we are running on that
executor. If not, the conformance fails.
Determining a descriptor's size requires reading its contents, but reading its contents from out of process requires knowing its size.
Build up the size incrementally by walking over the TrailingObjects. Take advantage of the fact that each trailing object's presence/count depends only on data that comes before it. This allows us to read prefixes that we gradually expand until we've covered the whole thing.
Add calls to TrailingObjects to allow iterating over the prefix sizes, and modify readContextDescriptor to use them. This replaces the old code which attempted to determine the descriptor size in an ad-hoc fashion that didn't always get it right.
rdar://146006006
When it's available, use an open-coded allocator function that returns
an alloca without popping if the allocator is nullptr and otherwise
calls swift_coro_alloc. When it's not available, use the malloc
allocator in the synchronous context.
This allows external tools to locate the metadata pointer without needing to call the accessor function.
This is only useful for non-generic types, so we borrow the HasCanonicalMetadataPrespecializations flag to indicate the presence of this pointer on non-generic types, and it continues to indicate the presence of prespecializations for generic types.
Only emit this pointer for internal/private types with no runtime initialization. Public type metadata can be found with the symbol, and it's not useful for types that require runtime initialization.
* [Concurrency] Initial steps for startSynchronously for Task
* [Concurrency] Rename to _startSynchronously while in development
* [Concurrency] StartSynchronously special executor to avoid switching
* startSynchronously bring back more info output
* [Concurrency] startSynchronously with more custom executor tests
* add missing ABI additions to test for x86
* [Concurrency] gyb generate _startSynchronously
* [Concurrency] %import dispatch for Linux startSynchronously test
* [Concurrency] Add TaskGroup.startTaskSynchronously funcs
* [Concurrency] DispatchSerialQueue does not exist on linux still
