This commit begins to generate correct metadata for @_objcImplementation extensions:
• Swift-specific metadata and symbols are not generated.
• For main-class @_objcImpls, we visit the class to emit metadata, but visit the extension’s members.
• Includes both IR tests and executable tests, including coverage of same-module @objc subclasses, different-module @objc subclasses, and clang subclasses.
The test cases do not yet cover stored properties.
In preparation for moving to llvm's opaque pointer representation
replace getPointerElementType and CreateCall/CreateLoad/Store uses that
dependent on the address operand's pointer element type.
This means an `Address` carries the element type and we use
`FunctionPointer` in more places or read the function type off the
`llvm::Function`.
This makes ClangImporter automatically conform C++ sequence types to `Cxx.CxxSequence` protocol.
We consider a C++ type to be a sequence type if it defines `begin()` & `end()` methods that return iterators of the same type which conforms to `UnsafeCxxInputIterator`.
We had two notions of canonical types, one is the structural property
where it doesn't contain sugared types, the other one where it does
not contain reducible type parameters with respect to a generic
signature.
Rename the second one to a 'reduced type'.
Put pointers to class_ro_t referenced from generic class patterns in a section __swift_rodatas such that they are discoverable by the linker.
The linker can then make the method lists contained in the class_ro_t relative like it can for objective c class metadata from non-generic swift classes.
rdar://66634459
Fixes a bug where descriptor for protocol requirement associated with
distributed thunk wasn't marked as `async` that results in ptrauth failures
because discriminator would be misaligned between requirement and witness.
Resolves: rdar://96520492
This teaches ClangImporter to synthesize conformances of C++ iterator types to `UnsafeCxxInputIterator` protocol from the `Cxx` module.
We consider a C++ type to be an iterator if it defines a subtype (usually a typedef or a using decl) called `iterator_category` that inherits from `std::input_iterator_tag`.
rdar://96235368
`PointerType::getElementType` has been removed entirely as part of the
opaque pointers migration. Update to `getPointerElementType` for now
until we've also migrated.
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.
If particular opaque type descriptor has multiple conditionally available
underlying types, emit a special type and witness reference accessors that
would be called at runtime to determine actual underlying type.
Avoid a reabstraction thunk every time an async let entry point is emitted,
by setting the context abstraction level while we emit the implicit closure.
Adjust some surrounding logic that breaks when we do this:
- When lowering a non-throwing function type against a throwing abstraction
pattern, include the error type in the lowered substituted type. Async
throwing and nonthrowing functions would require another thunk to convert
away the throwingness of the async context, which would defeat the purpose.
- Adjust the code in IRGen that pads the initial context size for `async let`
entry points so that it works when the entry point has not yet emitted, by
marking the async function pointer to be padded later if it isn't defined
yet.
