Type descriptors cannot always be referenced directly (i.e. when
a type is declared in a different module), so let's use
`getAddrOfLLVMVariableOrGOTEquivalent` facility that knows how
to handle that correctly.
Resolves: rdar://problem/103878515
This is done using a condition variable upon which the awaiting thread
will block if the continuation has not be resumed by the point of await.
The resuming thread will signal this condition variable, thereby
unblocking the awaiting thread.
Rdar://99977665
We were detaching the child by just modifying the list, but the cancellation path was assuming that that would not be done without holding the task status lock.
This patch just fixes the current runtime; the back-deployment side is complicated.
Fixes rdar://88398824
This replaces a number of `#include`-s like this:
```
#include "../../../stdlib/public/SwiftShims/Visibility.h"
```
with this:
```
#include "swift/shims/Visibility.h"
```
This is needed to allow SwiftCompilerSources to use C++ headers which include SwiftShims headers. Currently trying to do that results in errors:
```
swift/swift/include/swift/Demangling/../../../stdlib/public/SwiftShims/module.modulemap:1:8: error: redefinition of module 'SwiftShims'
module SwiftShims {
^
Builds.noindex/swift/swift/bootstrapping0/lib/swift/shims/module.modulemap:1:8: note: previously defined here
module SwiftShims {
^
```
This happens because the headers in both the source dir and the build dir refer to SwiftShims headers by relative path, and both the source root and the build root contain SwiftShims headers (which are equivalent, but since they are located in different dirs, Clang treats them as different modules).
The new intrinsic, exposed via static functions on Task<T, Never> and
Task<T, Error> (rethrowing), begins an asynchronous context within a
synchronous caller's context. This is only available for use under the
task-to-thread concurrency model, and even then only under SPI.
When detecting that an associated type's substituted type is an opaque type, read out its opaque type descriptor to collect the names of protocols it must conform to.
Implement casting to and from extended existentials. This is done by slightly generalizing the conditional conformances checking infrastructure.
Unfortunately, casts for reference types and metatypes are unsound because IRGen is peepholing all non-opaque existential conversions with a helper. I’ll disable that in a follow-up.
rdar://92197049
Anonymous contexts (e.g. types nested inside functons) require special handling when we are constructing a fully-qualified name. We construct the name by walking from a type's descriptor to its parent contexts. Previously, we would give up upon encountering an anonymous contexts.
This change refactors fully-qualified name construction to happen in two phases:
1. Collect a full context ancestor chain
2. Walk the chain backwards to reconstruct the fully-qualified name
As opposed to the previous approach which always constructed the name while recursively walking to the parent context. This is required because types nested inside anonymous contexts are represented in the fully-qualified type name as `(type_name in $XXXXXXXX)` where XXXXXXXX is the address of the context descriptor of the parent anonymous context.
Resolves rdar://91073103
Tidy up the metadata definitions.
* Generalize a number of metadata kinds for out-of-process clients
* Introduce conveniences to make runtime lookups easier
* Introduce TargetExistentialTypeExpression to TrailingObjects stops complaining about OverloadTokens being ambiguous
Note that there is no impact on the layout of the metadata - the changes here are all ABI-compatible.
I wrote out this whole analysis of why different existential types
might have the same logical content, and then I turned around and
immediately uniqued existential shapes purely by logical content
rather than the (generalized) formal type. Oh well. At least it's
not too late to make ABI changes like this.
We now store a reference to a mangling of the generalized formal
type directly in the shape. This type alone is sufficient to unique
the shape:
- By the nature of the generalization algorithm, every type parameter
in the generalization signature should be mentioned in the
generalized formal type in a deterministic order.
- By the nature of the generalization algorithm, every other
requirement in the generalization signature should be implied
by the positions in which generalization type parameters appear
(e.g. because the formal type is C<T> & P, where C constrains
its type parameter for well-formedness).
- The requirement signature and type expression are extracted from
the existential type.
As a result, we no longer rely on computing a unique hash at
compile time.
Storing this separately from the requirement signature potentially
allows runtimes with general shape support to work with future
extensions to existential types even if they cannot demangle the
generalized formal type.
Storing the generalized formal type also allows us to easily and
reliably extract the formal type of the existential. Otherwise,
it's quite a heroic endeavor to match requirements back up with
primary associated types. Doing so would also only allows us to
extract *some* matching formal type, not necessarily the *right*
formal type. So there's some good synergy here.
