Take advantage of the ability to iterate over TrailingObjects when computing the size of certain kinds of type metadata. This avoids the occasional issue where a new trailing object is added to a type, the remote metadata reader isn't fully updated for it, and doesn't read enough data. This change fixes an issue with function type metadata where we didn't read the global actor field.
Not all type metadata is amenable to this, as some don't use TrailingObjects for their trailing data (e.g. various nominal types) and extended existentials need to dereference their Shape pointer to determine the number of TrailingObjects, which needs some additional code when done remotely. We are able to automatically calculate the sizes of Existential and Function.
rdar://162855053
functions.
These were introduced in an early draft implementation of async let, but
never used by a released compiler. They are not used as symbols by any
app binaries. There's no reason to keep carrying them.
While I'm at it, dramatically improve the documentation of the remaining
async let API functions.
To enable ABIs which store extra info in the frame, add two new slots to
the coroutine allocator function table. For example, a frame could have
a header containing a context pointer at a negative offset from the
address returned from `swift_coro_alloc_frame`. The frame deallocation
function would then know to deallocate more space correspondingly.
Doing so enables allocators to contain additional context for use by
allocation functions. Because the allocator is already passed to
_swift_coro_alloc, on the fast path (no allocator, popless) no
allocation function is used, and the allocator is passed in the
swiftcoro register, this is cheap.
Allocator structs are passed in to new ABI yield-once coroutines and
contain pointers to functions to de/allocate memory. Here, those
pointers are signed.
This patch adds parsing and extracting of the Swift reflection
metadata data segments from within the WebAssembly DATA section and
tests it using swift-reflection-dump. This is needed to allow LLDB to
acces Swift reflection metadata when attached to WebAssembly
processes.
rdar://159217213
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.
