Changes the task, taskGroup, asyncLet wait funtion call ABIs.
To reduce code size pass the context parameters and resumption function
as arguments to the wait function.
This means that the suspend point does not need to store parent context
and resumption to the suspend point's context.
```
void swift_task_future_wait_throwing(
OpaqueValue * result,
SWIFT_ASYNC_CONTEXT AsyncContext *callerContext,
AsyncTask *task,
ThrowingTaskFutureWaitContinuationFunction *resume,
AsyncContext *callContext);
```
The runtime passes the caller context to the resume entry point saving
the load of the parent context in the resumption function.
This patch adds a `Metadata *` field to `GroupImpl`. The await entry
pointer no longer pass the metadata pointer and there is a path through
the runtime where the task future is no longer available.
`TaskGroup::offer(completedTask)`:
* Called from `AsyncTask::completeFuture()` which already takes care of
`release(completedTask)`. No additional edge is required if no task
is waiting and completed task is stored so it can be retrieved by
`group.poll()`.
* If group has waiting task, it will be dequeued and scheduled, add
`acquire(waitingTask)`.
`TaskGroupImpl::poll(waitingTask)`:
* If no pending tasks, do nothing.
* If returning finished task, `acquire(finishedTask)`.
* If enqueuing waiting task, `release(waitingTask)`.
Note: `release()` should go before, and `acquire()` after the annotated
synchronization operation.
Radar-Id: rdar://75910632
- stop storing the parent task in the TaskGroup at the .swift level
- make sure that swift_taskGroup_isCancelled is implied by the parent
task being cancelled
- make the TaskGroup structs frozen
- make the withTaskGroup functions inlinable
- remove swift_taskGroup_create
- teach IRGen to allocate memory for the task group
- don't deallocate the task group in swift_taskGroup_destroy
To achieve the allocation change, introduce paired create/destroy builtins.
Furthermore, remove the _swiftRetain and _swiftRelease functions and
several calls to them. Replace them with uses of the appropriate builtins.
I should probably change the builtins to return retained, since they're
working with a managed type, but I'll do that in a separate commit.
Take the existing CompatibilityOverride mechanism and generalize it so it can be used in both the runtime and Concurrency libraries. The mechanism is preprocessor-heavy, so this requires some tricks. Use the SWIFT_TARGET_LIBRARY_NAME define to distinguish the libraries, and use a different .def file and mach-o section name accordingly.
We want the global/main executor functions to be a little more flexible. Instead of using the override mechanism, we expose function pointers that can be set by the compatibility library, or by any other code that wants to use a custom implementation.
rdar://73726764
Throwing functions pass the error result in `swiftself` to the resume
partial function.
Therefore, `() async -> ()` to `() async throws -> ()` is not ABI compatible.
TODO: go through remaining failing IRGen async tests and replace the
illegal convert_functions.
Most of the async runtime functions have been changed to not
expect the task and executor to be passed in. When knowing the
task and executor is necessary, there are runtime functions
available to recover them.
The biggest change I had to make to a runtime function signature
was to swift_task_switch, which has been altered to expect to be
passed the context and resumption function instead of requiring
the caller to park the task. This has the pleasant consequence
of allowing the implementation to very quickly turn around when
it recognizes that the current executor is satisfactory. It does
mean that on arm64e we have to sign the continuation function
pointer as an argument and then potentially resign it when
assigning into the task's resume slot.
rdar://70546948
First, just call an async -> T function instead of forcing the caller
to piece together which case we're in and perform its own copy. This
ensures that the task is actually kept alive properly.
Second, now that we no longer implicitly depend on the waiting tasks
being run synchronously, go ahead and schedule them to run on the
global executor.
This solves some problems which were blocking the work on TLS-ifying
the task/executor state.
This is conditional on UseAsyncLowering and in the future should also be
conditional on `clangTargetInfo.isSwiftAsyncCCSupported()` once that
support is merged.
Update tests to work either with swiftcc or swifttailcc.
Previously, the error stored in the async context was of type SwiftError
*. In order to enable the context to be callee released, make it
indirect and change its type to SwiftError **.
rdar://71378532
* Adds support for generating code that uses swiftasync parameter lowering.
* Currently only arm64's llvm lowering supports the swift_async_context_addr intrinsic.
* Add arm64e pointer signing of updated swift_async_context_addr.
This commit needs the PR llvm-project#2291.
* [runtime] unittests should use just-built compiler if the runtime did
This will start to matter with the introduction of usage of swiftasync parameters which only very recent compilers support.
rdar://71499498