Language features like erasing concrete metatype
values are also left for the future. Still, baby steps.
The singleton ordinary metatype for existential types
is still potentially useful; we allow it to be written
as P.Protocol.
I've been somewhat cavalier in making code accept
AnyMetatypeType instead of a more specific type, and
it's likely that a number of these places can and
should be more restrictive.
When T is an existential type, parse T.Type as an
ExistentialMetatypeType instead of a MetatypeType.
An existential metatype is the formal type
\exists t:P . (t.Type)
whereas the ordinary metatype is the formal type
(\exists t:P . t).Type
which is singleton. Our inability to express that
difference was leading to an ever-increasing cascade
of hacks where information is shadily passed behind
the scenes in order to make various operations with
static members of protocols work correctly.
This patch takes the first step towards fixing that
by splitting out existential metatypes and giving
them a pointer representation. Eventually, we will
need them to be able to carry protocol witness tables
Swift SVN r15716
There's still a lot of manual intervention required, but
at least we don't have the constants written in two different
places.
Should be NFC.
Swift SVN r15242
Building the field type vector is potentially expensive and the vector isn't needed unless we do reflectiony things to a type, so let's use a lazy accessor. Make room for it, but don't populate it yet, so we can deal with fallout from the metadata layout change.
Swift SVN r15194
They aren't buying us anything until we thread through the custom ABI
work into Swift. I'm told this won't happen for a while. Until then,
they're just double the intermediate work in this area.
Swift SVN r15004
Now that we can read definitions directly from "C" headers, stop trying
to maintain a mirror of the HeapObject struct in Swift code in the
standard library.
Swift SVN r14982
Implicit conversions to and from an unsigned long long enum class give us the calling convention we want for swift_allocBox without totally destroying the API for C callers.
Swift SVN r14919
For ObjC classes, use class_copyIvarList to walk the ivars, and produce the summary string using -debugDescription. Still to come:
- visiting the base class as a child, and
- calling -debugQuickLookObject to get the quicklook object. Still waiting on a final design for the IDERepresentation API.
Swift SVN r14626
This change removes a broken simulator hack because we don't enable the
fast cache for the simulator anymore, and even if we did, ALLOC_CACHE_COUNT
must be 56 or 64, not 32 (for 32-bit and 64-bit respectively).
Swift SVN r14447
A useful unsafe optimization for potential implementations of Mirror that have existing heap storage to share from the value, like for Array or Dictionary.
Swift SVN r14186
Define a "Mirror" protocol with methods for querying the number of children a structured value has, getting the name and mirror for each of those children, and a string and "IDE representation" of the value, as needed by playgrounds and by our planned generic printing facility.
In the runtime, define a "reflect" function that can provide a Mirror for any object, either using a "Reflectable" protocol conformance if available, or falling back to a magic implementation in the runtime that grovels the type metadata. Stub out a bare minimum default implementation.
Swift SVN r14139
This is more in line with all other modules currently on our system.
If/when we get our final name for the language, we're at least now set
up to rename the library without /too/ much trouble. (This is mostly just
a lot of searching for "import swift", "swift.", "'swift'", and '"swift"'.
The compiler itself is pretty much just using STDLIB_NAME consistently now,
per r13758.)
<rdar://problem/15972383>
Swift SVN r14001
Mock up a naive Printable protocol, and do some dirty tricks in the runtime to implement a 'printAny' function that uses swift_conformsToProtocol to look up a conformance to Printable if the type has one, or falls back to a dumb opaque printing if it doesn't. Use this to make Array<T> Printable in some way or another for all T.
Swift SVN r13902
Given our constraints for 1.0, we can actually sort-of look up protocol conformances just by dlsym'ing the symbol for their protocol witness table, since we won't be implementing runtime witness table instantiation or private conformances anytime soon. To make this work for generic types, distastefully regress our mangling for protocol conformances by assuming all generic conformances are completely general to the unbound generic type and leave the generic parameters out of the mangling.
Swift SVN r13901
This lets IRGen avoid emitting an alloca for common generic metadata instantiations. These entry points can also be marked "readnone", and the general getGenericMetadata entry point can be "readonly", giving LLVM's optimizer a fighting chance on unspecialized generic code.
Swift SVN r12789
Start using null-page values as extra inhabitants when laying out single-payload enums that contain class pointers as their payload type. Don't use inhabitants that set the lowest bit, to avoid trampling potential ObjC tagged pointer representations. This means that 'T?' for class type T now has a null pointer representation. Enums with multiple empty cases, as well as nested enums like 'T??', should now have optimal representations for class type T as well.
Note that we don't yet expose extra inhabitants for aggregates that contain heap object references, such as structs with class fields, Swift function types, or class-bounded existentials (even when the existential has no witness tables).
Swift SVN r10061
I tried hard find all references to 'func' in documentation, comments and
diagnostics, but I am sure that I missed a few. If you find something, please
let me know.
rdar://15346654
Swift SVN r9886
When we need a reference to protocol or protocol composition type metadata, ask for it through the runtime, instead of referencing statically-emitted protocol metadata.
Swift SVN r9871
Same deal as for opaque existentials--pre-instantiate a static witness table for one-witness-table types (the zero-witness-tables case is nicely handled by Builtin.ObjCPointer's value witness), and generate a vwtable using dynamic witness implementations for each different-sized container on demand as necessary.
Swift SVN r9850
We can use these instead of objc_retain/objc_release for heap objects of unknown provenance, such as the references inside class existentials. We could use them in IRGen as well.
Swift SVN r9849
The assign-with-copy operation on existentials is complex enough to be emitted as a function call, which is currently generated on-demand by IRGen for every existential layout. We can instead use the implementation out of the runtime. Provide entry points for zero, one, and any number of witness tables.
Swift SVN r9815
Set up a metadata cache for existential type metadata. Instantiate existential metadata by first sorting the protocol list, so that it is order invariant, precomputing the overall witness table count and class constraint of the composition so it can be cached in the existential metadata.
We still need to implement value witnesses for existential containers in the runtime before this is complete. We can at least test the uniquing and flags computations at this point.
Swift SVN r9727
We'll emit protocol descriptors with ObjC-compatible layout. Existential type metadata will be instantiated by the runtime and reference these descriptors to describe the type.
Swift SVN r9708
