A lot of files transitively include Expr.h, because it was
included from SILInstruction.h, SILLocation.h and SILDeclRef.h.
However in reality most of these files don't do anything
with Exprs, especially not anything in IRGen or the SILOptimizer.
Now we're down to 171 files in the frontend which depend on
Expr.h, which is still a lot but much better than before.
This is a bit of a hack to dodge an assertion. In essence, it's a
harmless hack, but we'd like to make the handling of optional and
unavailable requirements more rigorous.
The protocol conformance checker verifies that all of the requirements
in the protocol's requirement signature are fulfilled. Save the
conformances from that check into the NormalProtocolConformance,
because this is the record of how that concrete type satisfies the
protocol requirements.
Compute, deserialize, and verify this information, but don't use it
for anything just yet. We'll use this to eliminate the "inherited
protocol map" and possibility some redundant type-witness
information.
...which don't need to have witnesses.
I can't seem to come up with a reduced test case for this one, but it
does fix a verifier failure in the larger project that triggered this.
rdar://problem/29744313
The typedef `swift::Module` was a temporary solution that allowed
`swift::Module` to be renamed to `swift::ModuleDecl` without requiring
every single callsite to be modified.
Modify all the callsites, and get rid of the typedef.
This is intended to have no functional effect, but there was a
minor change to a diagnostic in invalid code in the tests for the
unfinished ASTScope code; I hope I didn't break anything more
fundamental there.
If the 'override' attribute appears on an invalid decl,
it is removed at the start of typeCheckDecl(). However if
the decl is nested inside a multi-statement closure which
is invalid for other reasons, we may have validated it
but not type checked it, in which case we don't want to
crash in the verifier.
withoutActuallyEscaping has a signature like `<T..., U, V, W> (@nonescaping (T...) throws<U> -> V, (@escaping (T...) throws<U> -> V) -> W) -> W, but our type system for functions unfortunately isn't quite that expressive yet, so we need to special-case it. Set up the necessary type system when resolving an overload set to reference withoutActuallyEscaping, and if a type check succeeds, build a MakeTemporarilyEscapableExpr to represent it in the type-checked AST.
The AST verifier is causing late deserialization of generic
environments, which in turn is causing the Clang importer to import
more classes, which don't end up getting proper destructors... causing
an AST verification error. For now, disable this AST verifier check,
because it's causing lots of brokenness rdar://problem/29741827.
A proper fix will take a bit more work.
- The DeclContext versions of these methods have equivalents
on the DeclContext class; use them instead.
- The GenericEnvironment versions of these methods are now
static methods on the GenericEnvironment class. Note that
these are not made redundant by the instance methods on
GenericEnvironment, since the static methods can also be
called with a null GenericEnvironment, in which case they
just assert that the type is fully concrete.
- Remove some unnecessary #includes of ArchetypeBuilder.h
and GenericEnvironment.h. Now changes to these files
result in a lot less recompilation.
That is, a property in a protocol with type 'Self' doesn't promise
that the result type always matches the type of 'self', just the type
of the conforming type. (For a method, a result type of 'Self' /does/
mean you get back a type based on the dynamic 'self', like
Objective-C's 'instancetype'.) This applies even to get-only
properties, and so their accessors should be treated consistently.
With this change, we can have the AST verifier check that getter and
setter types always match up with their property.
While not strictly needed for type checking, it's extremely useful for
debugging and verification to know what context a particular generic
environment is associated with. This information was in a kludgy side
table, but it's worth a pointer in GenericEnvironment to always have
it available.
First, ensure all ParamDecls that are synthesized from scratch are given
both a contextual type and an interface type.
For ParamDecls written in source, add a new recordParamType() method to
GenericTypeResolver. This calls setType() or setInterfaceType() as
appropriate.
Interestingly enough a handful of diagnostics in the test suite have
improved. I'm not sure why, but I'll take it.
The ParamDecl::createUnboundSelf() method is now only used in the parser,
and no longer sets the type of the self parameter to the unbound generic
type. This was wrong anyway, since the type was always being overwritten.
This allows us to remove DeclContext::getSelfTypeOfContext().
Also, ensure that FuncDecl::getBodyResultTypeLoc() always has an interface
type for synthesized declarations, eliminating a mapTypeOutOfContext()
call when computing the function interface type in configureInterfaceType().
Finally, clean up the logic for resolving the DynamicSelfType. We now
get the interface or contextual type of 'Self' via the resolver, instead
of always getting the contextual type and patching it up inside
configureInterfaceType().
After recent changes, this asserts on all decls that are not VarDecls,
so we can just enforce that statically now. Interestingly, this turns
up some dead code which would have asserted immediately if called.
Also, replace AnyFunctionRef::getType() with
AnyFunctionRef::getInterfaceType(), since the old
AnyFunctionRef::getType() would just assert when called on
a Decl.
This handles situation when overload for the subscript hasn't been resolved
by constraint solver, such might happen, for example, if solver was allowed to
produce solutions with free or unresolved type variables (e.g. when running diagnostics).
Resolves: <rdar://problem/27329076>, <rdar://problem/28619118>, <rdar://problem/2778734>.
The uses of this function that want *all* nested types now go through
an entry point getAllNestedTypes(), and will need to be removed to
support recursive protocol constraints.
The uses of this function that only want to see what's been expanded
so far---dumpers and verifiers, mainly---can use
getKnownNestedTypes(), which may change type but is a reasonable
operation to continue using.
1. Add new AccessScope type that just wraps a plain DeclContext.
2. Propagate it into all uses of "ValueDecl::getFormalAccessScope".
3. Turn all operations that combine access scopes into methods on AccessScope.
4. Add the "private" flag to distinguish "private" from "fileprivate"
scope for top-level DeclContext.
The witnesses in a NormalProtocolConformance have never been
completely serialized, because their substitutions involved a weird
mix of archetypes that blew up the deserialization code. So, only the
witness declarations themselves got serialized. Many clients (the type
checker, SourceKit, etc.) didn't need the extra information, but some
clients (e.g., the SIL optimizers) would end up recomputing this
information. Ick.
Now, serialize the complete Witness structure along with the AST,
including information about the synthetic environment, complete
substitutions, etc. This should obsolete some redundant code paths in
the SIL optimization infrastructure.
This (de-)serialization code takes a new-ish approach to serializing
the synthetic environment in that it avoids serializing any
archetypes. Rather, it maps everything back to interface types during
serialization, and deserialization forms a new generic environment
(with new archetypes!) on-the-fly, mapping deserialized types back
into that environment (and to those archetypes). This way, we don't
have to maintain identity of archetypes in the deserialization code,
and might get some better re-use of the archetypes.
More of rdar://problem/24079818.
Reimplement the witness matching logic used for generic requirements
so that it properly models the expectations required of the witness,
then captures the results in the AST. The new approach has a number of
advantages over the existing hacks:
* The constraint solver no longer requires hacks to try to tangle
together the innermost archetypes from the requirement with the
outer archetypes of the context of the protocol
conformance. Instead, we create a synthetic set of archetypes that
describes the requirement as it should be matched against
witnesses. This eliminates the infamous 'SelfTypeVar' hack.
* The type checker no longer records substitutions involving a weird
mix of archetypes from different contexts (see above), so it's
actually plausible to reason about the substitutions of a witness. A
new `Witness` class contains the declaration, substitutions, and all
other information required to interpret the witness.
* SILGen now uses the substitution information for witnesses when
building witness thunks, rather than computing all of it from
scratch. ``substSelfTypeIntoProtocolRequirementType()` is now gone
(absorbed into the type checker, and improved from there), and the
witness-thunk emission code is simpler. A few other bits of SILGen
got simpler because the substitutions can now be trusted.
* Witness matching and thunk generation involving generic requirements
and nested generics now works, based on some work @slavapestov was
already doing in this area.
* The AST verifier can now verify the archetypes that occur in witness substitutions.
* Although it's not in this commit, the `Witness` structure is
suitable for complete (de-)serialization, unlike the weird mix of
archetypes previously present.
Fixes rdar://problem/24079818 and cleans up an area that's been messy
and poorly understood for a very, very long time.
On every `pushScope` the generic environment of this scope is appended
to `GenericEnv`. If the pushed `DeclContext` isn't generic, `NULL` is
pushed leading to a crash only in `DenseMap::find` if some archetypes
escaped their generic context.
In most places where we were checking "is<ErrorType>()", we now mean
"any error occurred". The few exceptions are in associated type
inference, code completion, and expression diagnostics, where we might
still work with partial errors.
There's a bit of a hack to deal with generic typealiases, but
overall this makes things more logical.
This is the last big refactoring before we can allow constrained
extensions to make generic parameters concrete. All that remains
is a small set of changes to SIL type lowering, and retooling
some diagnostics in Sema.
Now that SILFunctions no longer reference a GenericParamList, we
don't need to de-serialize cross-module references to archetypes
anymore.
This was the last remaining usage of AllArchetypes, so we can
finally rip it out.
A GenericEnvironment stores the mapping between GenericTypeParamTypes
and context archetypes (or eventually, concrete types, once we allow
extensions to constrain a generic parameter to a concrete type).
The goals here are two-fold:
- Eliminate the GenericTypeParamDecl::getArchetype() method, and
always use mapTypeIntoContext() instead
- Replace SILFunction::ContextGenericParams with a GenericEnvironment
This patch adds the new data type as well as serializer and AST
verifier support. but nothing else uses it yet.
Note that GenericSignature::get() now asserts if there are no
generic parameters, instead of returning null. This requires a
few tweaks here and there.
