Pull the implicit 'Self' associated type out of the protocol and into
an implicitly-declared generic parameter list for the protocol. This
makes all of the methods of a protocol polymorphic, e.g., given
protocol P {
typealias Assoc
func getAssoc() -> Assoc
}
the type of P.getAssoc is:
<Self : P> (self : @inout P) -> () -> Self.Assoc
This directly expresses the notion that protocol methods are
polymorphic, even though 'Self' is always implicitly bound. It can be
used to simplify IRgen and some parts of the type checker, as well as
laying more of the groundwork for default definitions within
protocols as well as sundry other improvements to the generics
system.
There are a number of moving parts that needed to be updated in tandem
for this. In no particular order:
- Protocols always get an implicit generic parameter list, with a
single generic parameter 'Self' that conforms to the protocol itself.
- The 'Self' archetype type now knows which protocol it is
associated with (since we can no longer point it at the Self
associated type declaration).
- Protocol methods now get interface types (i.e., canonicalizable
dependent function types).
- The "all archetypes" list for a polymorphic function type does not
include the Self archetype nor its nested types, because they are
handled implicitly. This avoids the need to rework IRGen's handling
of archetypes for now.
- When (de-)serializing a XREF for a function type that has an
interface type, use the canonicalized interface type, which can be
meaningfully compared during deserialization (unlike the
PolymorphicFunctionType we'd otherwise be dealing with).
- Added a SIL-specific type attribute @sil_self, which extracts the
'Self' archetype of a protocol, because we can no longer refer to
the associated type "P.Self".
Swift SVN r9066
Introduces a new kind of function type, GenericFunctionType, that
represents a polymorphic function type with all of its generic
parameters and requirements stored in a more readily canonicalizable
form. It is meant to eventually replace PolymorphicFunctionType, but
for now we build it up in parallel so we can switch over to it
pieacemeal.
Note: this representation is built and then thrown away. We'll start
recording it soon.
Swift SVN r8881
When type checking, allow the caller to customize the resolution of generic
type parameter types based on the context, for example, by choosing to
substitute in an archetype (or not) and allowing one to resolve a dependent
member reference via a specific archetype.
No actual functionality change here.
Swift SVN r8797
Right now the type checker is responsible for marking known protocols in the
imported AST for 'swift' module. If we don’t run the type checker, known
protocols are not marked correctly.
This patch moves the code to mark known protocols from libSema to libAST and
calls it when we load the standard library module.
Motivation: Swift tools might want to deserialize a module and inspect the AST
(for example, print it). There is no need to invoke the type checker in this
case, and we don’t even have a TU.
Swift SVN r8704
The type substitution still depends fairly heavily on the type
checker, which is accessed via the LazyResolver abstract
interface. That interface should get simpler, and become unnecessary
except to deal with lazy type checking, over time. At that point, it
will become optional, and Type::subst() will be usable without a type
checker around.
Swift SVN r8099
Fixes two bugs in Clang importer and deserialization code that were found by
the verifier:
(1) FuncExprs were created with a null FuncDecl
(2) BoundGenericType that was created by Clang importer for UnsafePtr<> and
other magic types did not have substitutions.
Swift SVN r8073
The new ConcreteDeclRef class provides a possibly-speciaized reference
to a declaration, which allows DynamicMemberRefExpr to refer to both
generic and non-generic members. without having to split the AST node.
Swift SVN r7839
functions whenever we build a reference to a [weak]
variable in the AST.
We're going to consume this during SIL-gen, so the
assumption here is that we never do SIL-gen of an Expr
that we didn't run through the type-checker.
Swift SVN r7716
We previously relied on the type checker to fill in the implementation
types (swift.Slice<T> and swift.Optional<T>, respectively), which
limited our ability to perform type transformations in the AST. Now,
the AST knows how to form these implementation types on demand.
Swift SVN r7587
This breaks the type-canonicalization link between a generic parameter
type and the archetype to which it maps. Generic type parameter types
are now separate entities (that can eventually be canonicalized) from
archetypes (rather than just being sugar).
Most of the front end still traffics in archetypes. As a step away
from this, allow us to type-check the generic parameter list's types
prior to wiring the generic type parameter declarations to archetypes,
using the new "dependent" member type to describe assocaited
types. The archetype builder understands dependent member types and
uses them to map down to associated types when building archetypes.
Once we have assigned archetypes, we revert the dependent identifier
types within the generic parameter list to an un-type-checked state
and do the type checking again in the presence of archetypes, so that
nothing beyond the generic-parameter-list checking code has to deal
with dependent types. We'll creep support out to other dependent types
elsewhere over time.
Swift SVN r7462
...by adding a new callback to ModuleLoader: loadDeclsConformingTo.
This is used only when the type checker doesn't have enough contextual
information to resolve an expression involving a literal, so it's
possible many *LiteralConvertible types will never be loaded.
Deserialization of types with conversion methods is still eager, since
there's no easy hook to tell when they're needed, but the list has been
renamed to refer to any decls that need to be eagerly deserialized, in
case we need it for other purposes in the future.
This probably won't help much in a real program, but it cuts the test
run time by about 5-10% in my build.
Swift SVN r7268
This is really two commits in one: first, change the AST and TypeChecker
to only track conformances to known protocols, and second, make sure we
can deserialize decls that conform to known protocols on demand. The
latter is necessary for the type checker to solve constraint systems that
are not fully constrained, and also requires tracking decls with conversion
methods.
Currently decls conforming to known protocols are eagerly deserialized;
that will change soon to be a new ModuleLoader callback. Decls with
conversion functions will continue to be eagerly deserialized for the near
future.
This fixes the initial regressions in making decl deserialization lazy.
Swift SVN r7264
- New type representation OptionalTypeRepr.
- New sugared type OptionalType.
- New base type SyntaxSugarType, parent of ArraySliceType and OptionalType.
These two are the same in a lot of ways.
- The form "T[]?" is forbidden, because it makes "Int[4][2]" oddly
different from "Int[4]?[2]". The type can be spelled "(T[])?" or
Optional<T[]>.
- Like Slice, "Optional" is just looked up in the current module. This may
or may not be the desired behavior in the long run.
<rdar://problem/14666783>
Swift SVN r7100
The current implementation of dealloc_stack in IR-gen is a
no-op, but that's very much wrong for types with non-trivial
local allocation requirements, e.g. archetypes. So we need
to be able to do non-trivial code here. However, that means
modeling both the buffer pointer and the allocated address
in SIL.
To make this more type-safe, introduce a SIL-specific
'[local_storage] T' type that represents the required
allocation for locally storing a T. alloc_stack now returns
one of those in additon to a *T, and dealloc_stack expects
the former.
IR-gen still implements dealloc_stack as a no-op, but
that's now easy to fix.
Swift SVN r6937
Factor the ProtocolConformance class into a small hierarchy of
protocol conformances:
- "normal" conformance, which provides a complete mapping for the
explicit conformance of a nominal type (which may be generic) to a
protocol;
- "specialized" conformance, which specializes a generic
conformance by applying a set of substitutions; and
- "inherited" conformance, which projects the conformance from a
superclass to a conformance for a subclass.
In this scheme "normal" conformances are fairly heavyweight, because
they provide a complete mapping. Normal conformances are unique,
because they're associated with explicit conformance declarations
(which cannot be repeated within a module; checking is TBD). Thus, IR
generation will eventually emit them as strong symbols.
"Specialized" and "inherited" conformances occur when we're dealing
with generic specializations or subclasses. They project most of their
members through to some underlying conformance, eventually landing at
a "normal" conformance. ASTContext is responsible for uniquing these
conformances when it sees them. The IR generation model for
specialized conformances will involve runtime specialization of the
underlying witness table; inherited conformances are probably no-ops
from the IR generation perspective.
Aside from being the right thing to do, having small, uniqued
conformances for the specialization and inheritance cases is good for
compile-time performance and memory usage. We're not really taking
advantage of this everywhere we could, yet.
This change uncovered a few existing issues (one known, one not
known), particularly because we're projecting inherited conformances
rather than building new conformances:
- <rdar://problem/14620454>: protocol witnesses to methods of
classes need to perform dynamic dispatch. See the
test/Interpreter/typeof.swift test for an example.
- <rdar://problem/14637688>: comparing NSString and String with ==
fails, because they are inter-convertible. I suspect we were missing
some protocol conformances previously, and therefore accepting this
obviously-invalid code.
Swift SVN r6865
We haven't fully updated references to union cases, and enums still are not
their own thing yet, but "oneof" is gone. Long live "union"!
Swift SVN r6783
When we notice that a type implicitly conforms to a protocol but is
not explicitly stated to do so, note this and provide a Fix-It
attaching the conformance to a declaration within the translation
unit, e.g.,
t.swift:28:16: error: type 'S1' does not explicitly conform to protocol 'P'
var p1 : P = S1()
^
t.swift:8:8: note: introduce explicit conformance to protocol 'P'
struct S1 : Q {
^
, P
Swift SVN r6760
Now that we have true serialized modules, the standard library can import
the Builtin module without any special direction (beyond -parse-stdlib),
and anyone can include those modules without special direction.
Swift SVN r6752
Previously, we only tracked the mapping from associated types to their
type witnesses. Now, also track the protocol conformances for each of
the requirements placed on the associated types.
Swift SVN r6655
importing them
Because going through the import for every code completion request is slow,
Clang code completion results are cached in the CodeCompletionContext. The
cache needs to be invalidated whenever a new Clang module is loaded. In order
to implement this, ModuleLoadListener class was added.
Swift SVN r6505
Elements of a tuple type now know if there is a default argument, and
what kind of default argument it is (callee side, __FILE__, __LINE__,
__COLUMN__), but they don't have an actual expression. There are a
number of cleanups this enables that will follow.
Note that the serialization support is as-yet-untested.
Swift SVN r6351
