To manage code size in user binaries, we want to be able to implement common completion handler signatures in
the Swift runtime once. Using a different mangling for these lets us add new ones without clobbering symbols in
existing binaries.
Emit a once token when adding canonical prespecialized metadata records
to a nominal type descriptor and add the token itself as a trailing
object to the type descriptor. The new token will, in subsequent
commits, enable the canonical prespecialized metadata records attached
to the type descriptor to be added to the metadata cache exactly once.
This attribute allows to define a pre-specialized entry point of a
generic function in a library.
The following definition provides a pre-specialized entry point for
`genericFunc(_:)` for the parameter type `Int` that clients of the
library can call.
```
@_specialize(exported: true, where T == Int)
public func genericFunc<T>(_ t: T) { ... }
```
Pre-specializations of internal `@inlinable` functions are allowed.
```
@usableFromInline
internal struct GenericThing<T> {
@_specialize(exported: true, where T == Int)
@inlinable
internal func genericMethod(_ t: T) {
}
}
```
There is syntax to pre-specialize a method from a different module.
```
import ModuleDefiningGenericFunc
@_specialize(exported: true, target: genericFunc(_:), where T == Double)
func prespecialize_genericFunc(_ t: T) { fatalError("dont call") }
```
Specially marked extensions allow for pre-specialization of internal
methods accross module boundries (respecting `@inlinable` and
`@usableFromInline`).
```
import ModuleDefiningGenericThing
public struct Something {}
@_specializeExtension
extension GenericThing {
@_specialize(exported: true, target: genericMethod(_:), where T == Something)
func prespecialize_genericMethod(_ t: T) { fatalError("dont call") }
}
```
rdar://64993425
swift::reflection::TypeInfo for (Clang-)imported non-Objective-C types. This is
needed to reflect on the size mixed Swift / Clang types, when no type metadata
is available for the C types.
This is a necessary ingredient for the TypeRef-based Swift context in
LLDB. Because we do not have reflection metadata for pure C types in Swift,
reflection cannot compute TypeInfo for NominalTypeRefs for those types. By
providing this callback, LLDB can supply this information for DWARF, and
reflection can compute TypeInfos for mixed Swift/C types.
Add `async` to the type system. `async` can be written as part of a
function type or function declaration, following the parameter list, e.g.,
func doSomeWork() async { ... }
`async` functions are distinct from non-`async` functions and there
are no conversions amongst them. At present, `async` functions do not
*do* anything, but this commit fully supports them as a distinct kind
of function throughout:
* Parsing of `async`
* AST representation of `async` in declarations and types
* Syntactic type representation of `async`
* (De-/re-)mangling of function types involving 'async'
* Runtime type representation and reconstruction of function types
involving `async`.
* Dynamic casting restrictions for `async` function types
* (De-)serialization of `async` function types
* Disabling overriding, witness matching, and conversions with
differing `async`
When a generic type from a different module is not resilient within the
current module and at least one of its arguments is from the current
module, emit a non-canonical prespecialized record, and access that
metadata via a call to swift_getCanonicalSpecializedMetadata, passing in
the non-canonical record.
rdar://problem/56996727
rdar://problem/56997022
Since libDemangling is included in the Swift standard library,
ODR violations can occur on platforms that allow statically
linking stdlib if Swift code is linked with other compiler
libraries that also transitively pull in libDemangling, and if
the stdlib version and compiler version do not match exactly
(even down to commit drift between releases). This lets the
runtime conditionally segregate its copies of the libDemangling
symbols from those in the compiler using an inline namespace
without affecting usage throughout source.
The TypeDecoder logic had a bug that caused crashes when it saw a tuple type with a variadic marker. Since variadic tuples aren't supported, this changes the logic to cleanly reject a tuple with a variadic marker.
This part of a series of patches to bring ASTPrinter and Swift Demangler to
feature parity, which is needed by LLDB, which depends on using the strings
produced by either interchangibly.
rdar://problem/64222171
`DifferentiableFunctionInst` now stores result indices.
`SILAutoDiffIndices` now stores result indices instead of a source index.
`@differentiable` SIL function types may now have multiple differentiability
result indices and `@noDerivative` resutls.
`@differentiable` AST function types do not have `@noDerivative` results (yet),
so this functionality is not exposed to users.
Resolves TF-689 and TF-1256.
Infrastructural support for TF-983: supporting differentiation of `apply`
instructions with multiple active semantic results.
This is analogous to ASTPrinter's FullyQualifiedTypesIfAmbiguous option.
This part of a series of patches to bring ASTPrinter and Swift Demangler to
feature parity, which is needed by LLDB, which depends on using the strings
produced by either interchangibly.
rdar://problem/63700540
This part of a series of patches to bring ASTPrinter and Swift Demangler to
feature parity, which is needed by LLDB, which depends on using the strings
produced by either interchangibly.
rdar://problem/63700540
This part of a series of patches to bring ASTPrinter and Swift Demangler to
feature parity, which is needed by LLDB, which depends on using the strings
produced by either interchangibly.
<rdar://problem/63700540>
When generic metadata for a class is requested in the same module where
the class is defined, rather than a call to the generic metadata
accessor or to a variant of typeForMangledNode, a call to a new
accessor--a canonical specialized generic metadata accessor--is emitted.
The new function is defined schematically as follows:
MetadataResponse `canonical specialized metadata accessor for C<K>`(MetadataRequest request) {
(void)`canonical specialized metadata accessor for superclass(C<K>)`(::Complete)
(void)`canonical specialized metadata accessor for generic_argument_class(C<K>, 1)`(::Complete)
...
(void)`canonical specialized metadata accessor for generic_argument_class(C<K>, count)`(::Complete)
auto *metadata = objc_opt_self(`canonical specialized metadata for C<K>`);
return {metadata, MetadataState::Complete};
}
where generic_argument_class(C<K>, N) denotes the Nth generic argument
which is both (1) itself a specialized generic type and is also (2) a
class. These calls to the specialized metadata accessors for these
related types ensure that all generic class types are registered with
the Objective-C runtime.
To enable these new canonical specialized generic metadata accessors,
metadata for generic classes is prespecialized as needed. So are the
metaclasses and the corresponding rodata.
Previously, the lazy objc naming hook was registered during process
execution when the first generic class metadata was instantiated. Since
that instantiation may occur "before process launch" (i.e. if the
generic metadata is prespecialized), the lazy naming hook is now
installed at process launch.
This cleans up some more `llvm::` leakage in the runtime when built into
a static library. With this change we are down to 3 leaking symbols in
the static library related to a missed ADT (`StringSwitch`).
This removes the last reference to the `llvm::` namespace in the
standard library. All uses of the LLVMSupport library now are
namespaced into the `__swift::__runtime` namespace. This allows us to
incrementally vend the LLVMSupport library and make the separation
explicit.
A malformed mangled name that ends in a truncated symbolic
reference could trigger a read beyond the end of the name.
This is because the code that grabs the next four bytes
bypasses the existing bounds checks. Insert an explicit
bounds check to guard against this.
There are a set of headers shared between the Swift compiler and the
runtime. Ensure that we explicitly use `llvm::ArrayRef` rather than
`ArrayRef` which is aliased to `::llvm::ArrayRef`. Doing so enables us
to replace the `ArrayRef` with an inline namespaced version fixing ODR
violations when the swift runtime is loaded into an address space with
LLVM.
Mangle `@noDerivative` parameters to fix type reconstruction errors.
Resolves SR-12650. The new mangling is non-breaking.
When differentiation supports multiple result indices and `@noDerivative`
results are added, we can reuse some of this mangling support.
Add mangling scheme for `@differentiable` and `@differentiable(linear)` function
types. Mangling support is important for debug information, among other things.
Update docs and add tests.
Resolves TF-948.
In order to allow this, I've had to rework the syntax of substituted function types; what was previously spelled `<T> in () -> T for <X>` is now spelled `@substituted <T> () -> T for <X>`. I think this is a nice improvement for readability, but it did require me to churn a lot of test cases.
Distinguishing the substitutions has two chief advantages over the existing representation. First, the semantics seem quite a bit clearer at use points; the `implicit` bit was very subtle and not always obvious how to use. More importantly, it allows the expression of generic function types that must satisfy a particular generic abstraction pattern, which was otherwise impossible to express.
As an example of the latter, consider the following protocol conformance:
```
protocol P { func foo() }
struct A<T> : P { func foo() {} }
```
The lowered signature of `P.foo` is `<Self: P> (@in_guaranteed Self) -> ()`. Without this change, the lowered signature of `A.foo`'s witness would be `<T> (@in_guaranteed A<T>) -> ()`, which does not preserve information about the conformance substitution in any useful way. With this change, the lowered signature of this witness could be `<T> @substituted <Self: P> (@in_guaranteed Self) -> () for <A<T>>`, which nicely preserves the exact substitutions which relate the witness to the requirement.
When we adopt this, it will both obviate the need for the special witness-table conformance field in SILFunctionType and make it far simpler for the SILOptimizer to devirtualize witness methods. This patch does not actually take that step, however; it merely makes it possible to do so.
As another piece of unfinished business, while `SILFunctionType::substGenericArgs()` conceptually ought to simply set the given substitutions as the invocation substitutions, that would disturb a number of places that expect that method to produce an unsubstituted type. This patch only set invocation arguments when the generic type is a substituted type, which we currently never produce in type-lowering.
My plan is to start by producing substituted function types for accessors. Accessors are an important case because the coroutine continuation function is essentially an implicit component of the function type which the current substitution rules simply erase the intended abstraction of. They're also used in narrower ways that should exercise less of the optimizer.
The demangler tolerates arbitrary suffixes on mangled names, and parses them as a Suffix node. When looking up a class by an ObjC mangled name, we don't want such demanglings to succeed, because this will result in false positives. It's expected that NSClassFromString(someClassName + "some suffix") will fail, unless something has actually created a class with that suffix.
rdar://problem/60012296
Archiving expects to be able to instantiate generic classes by name. This previously worked if you had instantiated the specialization in question, because the ObjC runtime would be able to look it up. Now, if the name hasn't been created, Swift has to look it up. demangleObjCTypeName doesn't do generics, so this failed.
rdar://problem/57674583
